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The Columbia University Libraries reserve the right to refuse to accept a copying order if, in its judgement, fulfillment of the order would involve violation of the copyright law. Author: Ure, Andrew Title: A dictionary of arts, manufactures, and...2V Place: New York Date: 1854 qs-si3g,i-i MASTER NEGATIVE # COLUMBIA UNIVERSITY LIBRARIES PRESERVATION DIVISION BIBLIOGRAPHIC MICROFORM TARGET ORIGINAL MATERIAL AS FILMED - EXISTING BIBLIOGRAPHIC RECORD jtt lu sujcs ; 140 Ur2 Ure, Andrew, 1778-1867. A dictionary of arts, manufactures, and mines; containing a clear exposition of their principles and practice, by Andrew Ure ••• Reprinted entire from the last corrected and greatly enlarged Eng- lish edition ••• New York, Appletoii, ld54. 2 V. illus., diagrs. 24P". L (Continued on next card) I u s I t>i e s 140 Ur2 Ure, Andrew, 1778-1857. A dictionary of arts, manufactures, and mines. 1854. ( Card 2 ) vc^--- A supplement to Ure's DictionarvoP^"^ arts, malltrf^tures and mines, containi«^"'a clear exposition of tlteix.m'iAciple^..€tnd^ practice. From the last e diti on, ^jjjd^^y Robert Hunt ... assisted by numep>«s contribu^ra...^. . New York, Appleton, illus., diagrs. 26^. J RESTRICTIONS ON USE: TECHNICAL MICROFORM DATA FILM SIZE: 3Si ry\rY\ DATE FILMED: REDUCTION RATIO: /2y IMAGE PLACEMENT: lA ® IB MB 2./22KS TRACKING # : _ INITIALS: W-W FILMED BY PRESERVATION RESOURCES, BETHLEHEM. PA. CO J^ .^ Wr^ %5^ <^ > O a m -n o o o CO X -< ^.. Ln 3 3 > 0,0 o m CO , ^ o o X N M o- ^c^: V. ^.^ o o 3 3 m o 3 3 8 3 3 O I Fr — r«i5i?Eis|g|s IH 1^ 1;^ I bo a- 00 f^ ^f^ ■^. 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LOND. ; M. ACAD. N.8. PHILAD. ; 8. PH. 800. N. OERM. HANOV. ; MULII. ETC. ETC. . > » > » r ♦ ILLUSTRATED WITfr NEARLY- SIXTEEN EIXDRED ENGRAVINGS ON WOOD » • t • » . , ' » » I . • •• • ••• •• t » • * % « " « » • EEPlUNVi,*p BNllRE FXOM' IHE ;..\ST 1 • t • « » • * CORRECTED AND GREATLY ENLARGED ENGLISH EDITION. IN TWO VOLUMES -VOL. L D. NEW-YORK : A P P L E T O N & COMPANY 3 46 » I • ( » « , . I PREFACE. It is the business of operative industry to produce, transfonn, and dis- tribute all such material objects as are suited to satisfy the wants of man- kind. The primary production of these olijects is assigned to the husband- man, the fisherman, and the miner ; their transformation to the manufaciu/ei and artisan; and their distribution to the engineer, shipwright, and sailor.* The unworked or raw materials are derived, — 1 from the organic processes of vegetables and animals, conducted cither witliout or with the fostering care of man ; 2. from the boundless stores of mineral and metallic wealth, arranged upon or within the surface; ol' the earth by the benignant Parent of our being, in the fittest condition to exercise our physical and intellectual powers in turning thorn to iho uses of life. The task which 1 havo undertaken in the present work, is to describe and explain the transforiurttions of these primary materials, by mechanical and chemical agencies, into general objects of exchangeable value, leav- ing, on the one hand, to the mechanical engineer, that of investigating the motive powers of transformation and transport ; and, on the other hand, to the handicraftsman, that of tracing their modifications into objects of special or local demand. Contemplated in this view, an art or manufacture may be defined to be that species of industry which efl'ects a certain change in a substance, to suit it for the general market, by combining its parts in a new order and form, through mechanical or chemical means. Iron will serve tlie purpose of illustrating the nature of the distinctions here laid down, between mechanical engineering ; arts and manufactures ; and handi- craft trades. The engineer perforates the ground with a shaft, or a drift, to the level of the ore, erects the pumps for drainage, the ventilating, and hoisting apparatus, along with the requisite steam or water power ; he con- structs the roads, the bridges, canals, railways, harbors, docks, cranes, &c., subservient to the transport of the ore and metal ; he mounts the steam or water-power, and bellows for working the blast-farnaces, the forges, and the cupolas ; his principal end and aim on all occasions being to overcome the forces of inertia, gravity, and cohesion. The ores extracted and sorted •For correct and copious information upon agricultural production, I nave great pleasure in referring my readers to Mr. Loudon's elaborate Encyclopedias of ^igriculiuref Gardening, and Plants ; and for mercantile production and distribution, to Mr. M'CuJ- loch'e excellent Dictionary of Commerce and Commercial Navigation, j^ PREFACE. , by the n,iner, and transported by ^^^ ^^^f^^:^^!^'^! t^'et^"™ there skilfuUy blended by the "°"-™f '«' ("'^"X S Sue proporUons ol in a furnace appropriately constructed along with theudu^^ P^.^ flux and fuel, whereby he ^reduces them ^ cast Kon ^^^^^^^ which he runs off at the right periods '«« ™"?" S "hemical agencies, he then transforms this crude "^^Wj^^^^J,^;^^ for the general market ; into bar and plate iron «fj''n«"/f'f ^h^^"'' -^^^^^^^ Z the Cementation fur- he finally .-""^erts the best oMheba^ hTb;st of 1 plates into tin-plate, nace, the forge, and the 'J'-h^"™^' ' «^ , j^.^ processes . into objects tag or E taJicB. » lb. loek.nua. g«i..m,th, .».h.n...h, eu«.m,«, •■■Si S- *. p™,p... -b» h._j= ..™i .<• j;-- - ■; 3»K ^fZ. ^nWt would hive presented a misceUaneous farrago of mcon- '^ou'sVr:id"%rn:m'ero:s to^allow of *!>- being expounded m^^^^^^ E:rar3:trs:titvTrbr^^^^ I readily '^'^^n^w'^ee / j^ ^ ^■^^ ^f selection ; havmg ^eTcr^^ai^ed IT nteul eTa^^^ influential friends.to introduce a few alleles which I would gladly have left to the mechanical cnnneer Of these Prin tVis one, Ihich, having had no provision made for." « my ordinal plafwas too' hastily compiled to ''dmit of my descnbing^^^^^ suitable figures, the flat-printing ='"'«™^"<= ™f H "ff a mecSrwhich wherewith the pages of this volume were worked ofi^; a mechanism wmcn Tregard as the^m^st elegant, precise, and productive, hitherto employed to PYPpiite the best Style of letter press. • „„ « I have imbodied in this work the results of my long experience as a Professor of Practical Science. Since the year 1805 when I entered aj an early age umm the arduous task of conducting the schools of chemistty and manufacmres in the Andersonian Institution, up to the present daj Tharbeen Suously engaged in the ^'J'-iy --^ ^PXTn^f sdonaSy the chemical and many of the mechamcal arts. Consulted professionally by pro^^eto s of facto'^ies, workshops, and mines of -"»"« "^ff^^P*^^: ^th in this country and abroad, concerning derangements m their opera ^ns or defect" nTheir products I have enjoyed peculiar opportunities of bccomk^e famtliar with their minutest details, and have frequently had the toTforfune to rectify what was amiss, or to supply what was wanting. §rfhes"ores of information thus acquired, I have availed "-y^^lf "J^ J^„: present occasion; careful, meanwhile, to neglect no means of kno«led„e which my extensive intercourse with foreign nations aflords . I therefore humbly hope that this work will prove a valuable contribution to the literature of science, serving — ,, . „ ^., ,_j Trades- /„ Ihe first place, to instruct the Manufacturer, Metallurpst and ■Trades^ man, in the principles of their respective processes, so as to render them m PREFACE. ▼ reality the masters of their business, and to emancipate them from a state of bondage to such as are too commonly the slaves of blmd prejudice and "^X^XTo afford to Merchants, Brokers, Drysalters, Druggists, and Officers of the Revenue, characteristic descriptions of the commodities which nass throusfh their hands. - , - a ^ Tkirdlv%y exhibiting some of the finest developments of chemistry and physics, to lay open an ixcellent practical school to students of these kindred *"lv^rtWv,-to teach Capitalists, who may be desirous of placing their funds in some productive bank of industry, to select judiciously among plausible 1 * 4, "" ^WMv] to enable Gentlemen of the Law to become well acquainted with the nature of those patent schemes which are so apt to give rise to litigation. Sixthly, to present to our Legislators such a clear exposition of our staple manufactures, as may dissuade them from enacting laws which obstruct industry, or cherish one branch of it to the injury of many others : and Lastly to give the General Reader, intent chiefly on intellectual cultivation, a view of many of the noblest achievements of science, m effectmg those grand transforr^ations of matter to which Great Britain owes her paramount wealth, rank, and power among the kingdoms. The latest statistics of every important object of manufacture is gjiven from the best, and, usually, from official authority, at the end of each article. The following summary of our manufactures is extracted from Mr Macqueen^s General Statistics of the British Empire, pubhshed in 1836. It shows the amount of capital embarked in the various departments of manu- /acturing industry, and of the returns of that capital :— Cotton manufactures Woollen ditto Silk ditto Linen ditto Leather ditto - , - Iron ditto, to making pig ux)n Iron, hardware, cutler}', &c. Copper and brass ditto China, glass, &c. . - - Paper, furniture, books, &c. Spirits (British), ales, soap, &c. Sundries additional - Capital. £ 40,973,872 36,000,000 8,000,000 12,000,000 13,000,000 10,000,000 25,000,000 3,600,000 8,600,000 10,000,000 37,600,000 Prodoce. £ 52,513,586 44,250.000 10,000,000 15,421,186 16,000,000 7,098,000 31,072,600 4,673,186 10,892,794 14,000,000 47,163,847 9,000,000 Totals 201,773,872 \ 262,085,199 | Although I am conscious of having used much diligence for many years in collecting information for this work, from every quarter within my re^^M^^^^ utmost pains in preparing it for publication, and incessant v^f '^"^f .f "'^g j^? passage trough the'preS, yet I am fully aware that ^ . ^^^^^^^^^^^^ errorTand defects. These I have studied to rectify in the text of this fourth ""^''sTnce this book is not a Methodical Treatise, but a Dictionary, one exten^ sive subject may be necessarily dispersed through many articles. Ihus, for ♦ Tlie statistics ofagricuUure, trade, and manufacture., are ably and fairly discu^ed in Mr. McCulloch's Dictionary/ already referred to. VI PREFACE. * i: example, information upon the manufacture of Colors will be found under azure ; black pigment ; bone-black ; bronze ; brown dye ; calico-printing ; carmine ; carthamus ; chromium ; cochineal ; crayons ; dyeing ; enamels ; gold; gilding; gamboge; gray dye; green dye; green paints; indigo; kermes; lac dye; lakes; madder; massicot; mercury, periodide of; Naples yellow; orange dye; orpiment; paints, grinding of; ochres; paper-hang- ings ; pastes ; pearl white ; Persian benies ; pottery pigments ; Prussian blue ; purple of Cassius ; red lead ; rouge ; Scheele's green ; Schweinfurth green ; stained glass; terra di Sienna; ultramarine; umber; verditer; vermilion; vitrifiable colors, weld, white lead ; woad, yellow king's. A casual consulter of the Dictionary, who did not advert to this distri- bution, might surmise it to be most deficient, where it is in reality most copious. The elaborate and costly Encyclopedias and Dictionaries of Arts, which have appeared from time to time in this countiy and abroad, have, for the most part, treated of the mechanical manufactures more fully and correctly than of the chemical. The operations of the former are, in fact, tolerably ob- vious and accessible to the inspection of the curious ; nor are they difficult to transfer into a book, with the aid of a draughtsman, even by a person but mode- rately versed in their principles. But those of the latter are not unfrequently involved in complicated manipulations, and depend, for their success, upon a delicate play of affinities, not to be understood without an operative familiarity with the processes themselves. Having enjoyed the best opportunities of studying the chemical arts upon the greatest scale, in this kingdom and on the Continent, I may venture, without the imputation of arrogance, to claim for my work, in this respect, more precision and copiousness than its prede- cessors possess. I have gone as far in describing several curious procease* hitherto veiled in mystery, as I felt warranted, without breach of confidence, to go ; regarding it as a sacred duty never to publish any secret whatever, without the consent of its proprietor. During my numerous tours through the factory districts of Great Britain, France, Belgium, Germany, and Switzer- land, many suggestions, however, have been presented to my mind, which I am quite at liberty to communicate in private, or carry into execution, in other districts too remote to excite injurious competition against the original inventors. I am also possessed of many plans of constructing manufactories, of which the limits of these volumes did not permit me to avail myself, but which I am ready to furnish, upon moderate terms, to proper applicants. May I venture to point attention to the very insecure tenure by which patents for chemical or chemico-mechanical inventions are held ; of which there is hardly one on record which may not be readily invaded by a person skilled in the resources of practical chemistry, or which could stand the ordeal of a court of law, directed by an experienced chemist. The specifications of such patents stand in need of a thorough reform ; being for the most part not only discreditable and delusive to the patentees, but calculated to involve them in one of the greatest of evils — a chancery suit While I gratefully acknowledge the indulgence with which this work has been received, may I be permitted to advert very briefly to some of my pre- sent endeavours to render it less undeserving of public favor, though, after all my etforts, it will by no means realize either my own wishes and intentions, or the expectations of all my readers? To investigate thoroughly any single branch of art, we should examine it in its origin, objects, connexion with kindred arts, its progressive advance- ment, latest improved state, and theoretical perfection. The general princi pies on which it is founded, whether belonging to the mechanical, the physical, PREFACE. vu \ I t i the chemical sciences, or to natural history, should be fully expounded, and tested by an application to its practical working on the great scale. The max- imum effect of the machinery which it employs, and the maximum product of the chemical mixtures and operations which it involves, should in every case be calculated and compared with the actual results. Such have been my motives in the numerous consultations I have had with manufacturers relatively to the establishment or amelioration of their fac- tories ; and when they a»e kept steadily in view, they seldom fail to disclose whatever is erroneous or defective, and thereby lead to improvement It will not be denied by any one conversant with the productive arts, that very few of them have been either cultivated or described in this spirit It is to be hoped, however, that the period is not remote, under the intellectual excite- ment and emulation now so prevalent in a peaceful world, when manu- factories will be erected, and conducted upon the most rational and economi- cal principles, for the common benefit of mankind. Meanwhile it is the duty of every professor of practical science to contribute his mite towards this de- sirable consummation. It is under a sense of this responsibility that I have written the leading articles of this edition, having enjoyed some peculiar advantages in my profes- sion for making the requisite researches and comparisons. I trust that not many of them deserve to be regarded as trite compilations or as frivolous nov- elties, with the exception of a few of the notices of recent patents, which I have intentionally exhibited as beacons to deter from the treacherous quick- sands, not as lights to friendly havens. I have sought sincerely to make them all conducive, more or less, to utility; being either new contributions to the old stock of knowledge, or additions and corrections to the present double volume. Manufacture is a word which, in the vicissitude of language, has come to signify the revei-se of its literal intrinsic meaning ; for it now denotes every extensive product of art which is made by machinery, with little or no aid of the human hand ; so that the most perfect manufacture is that which dispenses entirely with manual labor. In every well-governed state of continental Europe there exists a Board of Health, or Cornell de Saluhrite composed of eminent physicians, chemists, and engineers, appointed to watch over whatever may aft'ect injuriously the public health and comfort In France, this commission consists, for the capi- tal, of seven membei-s, who have the surveillance', in this respect, of markets, factories, places of public amusement, bakeries, shambles, secret medicines, Park ) Result Area. 112 8-69 lbs. Atml 56 7-83 lbs. Area. US 7-62 lbs. Lynvi coal Result Area. 112 9-61 lbs. Area. 56 8-89 lbs. 84 9-08 IbiL Balcarras five feet nine Result Area. 112 7-79 lbs. Area. 56 6-60 lbs. Aiea. 84 7-23 lbs. Hastings Hartley Result Area. 112 8-18 lbs. Area. 56 7-65 lbs. Area. 84 7-49 Iba. And in precisely the same condition are the Balcarras Arley, Carr's Hart- ley, Hedley's Hartley, Bate's West Hartley, Davison's West Hartley, Cowpen and Sidney Hartley, Hill's Plymouth Coals, the Willington Coal, the Wigan Four Foot Seam, and a host of others, in Report No. 3, all of which would no doubt have given a better result with an increased opening in the damper. Conversely, we find many others with too large an opening, as for example : North Percy ) Hartley ) Result Balcarras Haigh Yard mine Result \ Area. 112 7-43 lbs. Ana. 112 6-79 lbs. Area. 56 7-74 lbs. Area. 56 8-65 lbs. Area. 84 7 54 Iba. 84 8-26 Ibei And about a dozen more throughout Reports 2 and 3, in which the greatest effect has been produced by the minimum of area, leading therefore to the inference that a more restrii^ted opening would have increased the value of the fuel. Taken as a whole, the only honest inference that can be ziy PREFACE. 1 SI drawn from the three Reports is, that the question sought to be solved by the Admiralty coal investigation remains exactly where it was for all practical purposes; the analyses, whether proximate, ultimate, or lithargic, together with the boiler experiments, being in all senses of the expression null, void, and of no effect or value whatever. And as a proof of the little care taken to insure accuracy to the whole per- formance, we find at page 10, Report No. 3, that even the simplest rules of arithmetic have been violated in a Table purporting to show the average composition of the coals from Wales, Newcastle, Lancashire, Scotland, and Derbyshire. This table gives, or ought to give, the composition of the re- spective coals in 100 parts, and strange to say, the results do not amount to 100 in any single instance : the Welsh coal is more, and the others less than 100, though the oxygen was calculated from the loss, London, 18 Upper Seymowr-ztreet^ IQth June, 1853. \ t DICTIONARY •V ARTS, MANUFACTURES, AND MINES. ABIETINR A pale yellow, transparent^ viscid exudation from the Abies pectinata^ a species of fir, growing in the neighborhood of Strasburg, and hence called Strasburg turpentine. It contains 35 per cent, of a volatile oil of an agreeable smell, combined with a resin, and a small quantity of the acid of amber, as well as the peculiar body called abietin, a resin of an acid kind, styled therefore by some abietic acid. If th« indifferent resin be removed by absolute alcohol, and the remainder digested with carbonate of potash, an abietate of potash is obtained. It dissolves in petroleum, and crystallizes out of it. It resembles Canadian balsam, and is used for attaching micro- scopic objects to glass slips. ACETAL, is the subacetate of ether ; having for its chemical symbol 3 Ac O -f- A« Oj. It is a light colorless ethereous liquid. ACETATE. {Acetate, Fr. ; Essigsaure, Germ.) Any saline compound of which the acetic is the acid constituent; as acetate of soda, of iron, of copper, j 1 Atom Alcohol — 2 Atoms Hydrogen =— Aldehyde -j- 2 Atoms Oxygen = Acetic Acid Hyd. C4HBO -f HO H, _ C4H, -fH O Oa C4 H, O, 4- H O. Ite atomic weight on the hydrogen scale is therefore 60 in the state of hydrate, and . Albumen, gluten, and vegetable matters which contain these substances, such as th« juice of beet-roots, operate also the oxidation of alcohol, and that the more rapidly the more ample the exposure of the mixture to the air. While sugar is transmuted into carbonic acid, and alcohol only through the intervention of gluten, alcohol sul^ fers that change by contact with finely divided platinum. It is hince probable, that to what is called acetous fermentation, the vital action of the particles of yeast is not indispensable, and that it belongs rather to the category of chemical combustion • to the contact action ofLiebig, the catalysis ofBerzelius, or %U polar cmnlnnation ofLihoia. In the vinegar of wine, malt, or that in which organic matter has been infused there appears a peculiar mould-plant, belonging to the genua Mycodemia Pers.- whiS IS usuaUy called vinegar mother. As the plant grows, it decomposes the acid, aad 8 ACETIC ACID. leaves eventually nothing but water. It contains proteine, and consequently azote, but leaves no ashes when burned. « i i i • The same circumstances which govern the conversion of alcohol mto vinegar, pre- side over that of wood spii it into formic acid (acid of ants), fusel oil (oil of grain) mto valerianic acid ; and probably butyric acid has some such organ. With regard to the formation of vinegar, M. Dumas observes that every fermentation has for its effect to dissociate a compound into a more simple state ; but the so-called acetous fermenta- tion unites alcohol or aldehyde with the oxygen of the air; being the ouly case in which fermentation represents a true combination. He admits, notwithstanding, that this fermentation, in a certain point of view, possesses the character of the other fer- mentive actions, namely, the concourse of an organized substance, and of an organic matter; the one being a ferment (the mother), and the other fermentable. The con- version of alcohol into vinegar never happens in common cases, without the aid of an albuminous substance, and of circumstances favorable to all fermentations, such as the presence of air, not only at its commencement, but during its entire course. The lactic fermentation has however been sometimes mistaken for the acetous; but it may be distinguished by its requiring no alcohol, but only starchy or saccharine matters ; and after it begins, exposure to air is not needed. It has been supposed that acetification is analogous to nitrification, as to the utility of porous bodies which di- vide the liquid and the air ; thus ammonia passed along with air through platinum sponge, gently ignited in a tube, produces nitric acid ; and pumicestone, in like cir- cumstances, combines sulphurous acid and oxygen into the sulphuric ; and so we have seen that a mixture of alcohol vapor and air under the influence of the same sponge is converted by a true oxidation of the ether (of the alcohol), first into aldehyde, and afterwards into acetic acid. A like oxidation takes place in the wine or beer, which being purposely left in casks partially filled, rises by capillarity on the wood above the liquid level, and is there subjected to the porous influence. The vinegar is much more rapidly generated, however, by the various artiticia) methods of multiplication of points of contact with the air, presently to be described. Vinegars may be arranged under four heads : 1. Malt or sugar vinegar ; 2. Wine and fruit vinegar ; 3. Alcohol vinegar ; 4. Wood vinegar. 1. Malt vinegar is manufactured most extensively in the United Kingdom, chiefly in England, to the amount of fully 3,000,000 of gallons, on which an excise duty of 2«t per gallon is levied, and for the license to manufacture it, 5/. annually must be paid. The total number of vinegar manufactories in this country is about fifty, of which five of the principal ones are in London, and these carry on at the same time the manu- facture of British wines, now happily emancipated from the trammels of the Excise. From 6 bushels of malt, properly crushed, 100 gallons of wort in whole may be ex- tracted by due mashing, the first water of infusion being of the temperature of 160° Fahr., and the next two progressively hotter, for exhausting the soluble saccharine matter. When the wort is cooled to 75°, from 3 to 4 gallons of good yeast are stirred into it in the fermenting tun, and when it has been in brisk fermentation for about 40 hours, it is racked off into used vinegar casks, laid upon their sides in a room heated with a stove for quick work ; or otherwise, during summer, in the open air, under ex- posure to the sun. The casks should be only about | filled, and left unclosed, or loose- ly covered from the rain at their bung holes, to favor the free acidifying action of tiie atmosphere. In the air, the acetic fermentation may not be completed till after the lapse of three months ; but in stove-rooms in much shorter time, according to the temperature. The sour liquor is then transferred from the several casks by means of a flexible pipe, and pumped into the stove-vat, whence it is run into the clarifying and flavoring casks, called "rapes," being here made to filter slowly and repeatedly through condensed heaps of the stalks and skins of raisins, called rape, which is the refuse of the British wine manufacture. Vinegar thus made contains always a considerable quantity of gluten, and is therefore liable to become mouldy and to putrify ; to coun- teract which, a certain portion of sulphuric acid may be legally, and is always, mixed with British-made vinegar ; but that portion is too often overpassed through aval ice, and is certainly injurious to health. I have found by analysis in a saniple of vinegar, made by one of the most eminent London manufacturers, with which he supplies the public no less than 175 grains of the strongest oil of vitriol per gallon, added to vine- gar containing only SB per cent, of real acetic acid; giving it an apparent strength after all of only 4 per cent. ; whereas standard commercial vinegar is rated at 5 per cent. It is a remarkable fact, that the people of this country have had their vinegar palate so depraved, that they prefer the vitriolized vinegar to the pure ; and that all attempts at introducing abetter article into general sale has proved abortive,— a fact discreditable to our nation, of which several instances have come before me. The complete acidification of malt wort by the above process bem^ very slow, has iriven rise to many projects, more or less successful, fov accelerating it So long ago as the year 1824, Mr. Ham, of Norwich, obtained a patent for exposing worts to tlie T ACETIC ACID. . t atmospheric air apon a most extensive surface, by means of a revolving pump, which caused a constant shower of it to fall upon and through a bundle of birch twigs supported in the middle of a large tun. The air had free access to the twigs. The wash, being kept at a temperature of from 90° to 100° Fahr., by steam pipes at the bottom of the tun, and continually repumped, became moderately acetified m 48 hours, and was finished into good vinegar, either by that process, or preferably by racking off into casks, and exposing it in them to a temperature of 86° Fahr. for 15 or 20 days. He also found that a wort made with 1 part of malt mixed with 6 of raw barley, properly mashed, afforded by this means an excellent vinegar. A wort of sp. gr. 1 060 (60 excise gravity) will yield a vinegar of revenue proof, or of 6 per cent of real acetie acid. This quick process belongs rather to the combustion class of chemical transform- ations than to that of the fermentative, as yeast is not essential, though it is found to prove serviceable, as in the corresponding formation of acetic acid from the oxygena- tion of alcohol some stale vinegar is used as a ferment, or as a contact agent Under Messrs. Ham's instructions four considerable manufactories of vinegar have been established, with the products of two of which I am practically conversant, and I am warranted by experimental proofs in declaring that the vinegar made by Messra. Hill, Evans, and Williams, of Worcester, and Messrs. Hills and Underwood, of Nor- wich and Easteheap, London, are perfect specimens of acetic acid for family use, and also for manufacturing purposes. The latter company liberally displayed, in the South Gallery of the Royal Exhibition, at No. 7. Class 3. substances used as food, a model of their acetifying apparatus, as mounted in their works. An excellent vinegar may be made for domestic purposes by adding to a syrup con- sisting of one pound and a quarter of sugar for every gallon of water, a quarter of a pint of pod yeast The liquor being maintained at a heat of from 75° to 80° Fahr, acetification will proceed so well that in 2 or 3 days it may be racked off from the sediment into the ripening cask, where it is to be mixed with 1 oz. of creiim of tartar, and 1 oz. of crushed raisins. When completely freed from the sweet taste, it should be drawn off clear into bottles, and closely corked up. The juices of currants, gooseber- ries, and many other indigenous fruits, may be acetified either alone, or in combination with syrup. Vinegar made by the above pro■« 1 1 1 ^ tl • ACETIC ACID. In Berzdius JahreH herkhte xvi. 192, the table of Van der Toom is ^iven for the successive quantities of dry acetic acid, corresponding to successive densities. lie rates the sp. gr. of the hydrate at 10670, being tlie acid which contains 85 11 of dry acid- In my table, the equivalent hydrate is marked J 062, a gravity as low as is probably to be obtained by weighing a solution of the drained crystals. An acid of 1-0698 contains, according to him, 61 of the dry; while an acid ot 10675 corresponds, in my table, to 60 of the hydrate, or 61 of dry acid. In general his gravities are a little greater than mine at corresponding degrees of acid strength. Tlie above numbers in my table are experimental, not interpolated from a few points, and may, I hope, be relied upon. The greatest density seems to be produced when two atoms of water — 18 are mixed with one of the hydrate ==- 60, or 23 with 77, at which dilution the differences of density are very small, and minute errors may have occurred. When 6 atoms of water are added to one of the hydrate, making 7 atoms of water in all, then the acid acquires its primitive liquid density of about 1062. A curious analogy exists in this respect with nitric acid, which suffers the greatest degree of condensation, in the series of its dilutions, when one atom of the real acid is combined with 7 atoms of water. Pure acetic acid possesses a peculiar pungent, though not disagreeable smell, and a strongly acid taste. It crystallizes in needles and plates when cooled to 65° Fahr and melts when heated to 61*''. The specific gravity of the crystals (taken by means of spirits of turpentine) I found to be M36 at 65° Fahr. The vapor of the boiling acid IS highly combustible, and burns with a blue flame. Acetic acid hydrate dissolves camphor, ghadine, resins, the fibrine of blood, and several organic compounds. When Its vapor is conducted through a slightly ignited porcelain tube, it is converted entirely •into carbonic acid and aceton, an atom of the acid being resolved into an atom of each of the resultants. At a white heat^ the vapor is converted into carbonic acid, carburetted hydrogen, and water. The acetates comport themselves at elevated tempe- ratures differently, according to the strength of affinity between the acid and the base. When this is weak the acid escapes unchanged, and the stronger it is, the more acid 18 converted into aceton. Acetate of barytes affords most of this spirituous liquor, and next to it the alkaline acetates and acetate of lead. Acetate of copper yields, at a heat of 400° or 600°, a concentrated acetic acid, mixed with some aceton. This process was formerly employed for preparing radical vinegar, as also that of decomposing that of acetate of lead, by sulphuric acid; but both are now renounced for the process by acetate of soda above described. Acetic acid is a pretty stable compound, as is evinced by its compound with soda and potash, bearing the heat of 600° Fahr. without decomposition. Acetate of potash and soda, dissolved in much water, readily mould and decompose ; but acetate of am- monia is not liable to change in close vessels. When acetic acid is distilled along with peroxide of manganese and sulphuric acid, it is converted into formic acid. Iodic acid has the same effect with precipitation of iodine: it reduces gold from its chloride without disengagement of carbonic acid ; but it does not reduce mercury from its ni- trate or sulphate, as formic acid does. The simplest reagent for purifying common vinegar is recently calcined wood char- coal in fine powder; with which it may be digested, or, what is better, distilled, where- by a portion of the water comes over first, and may be got rid of, while the stronger vinegar is a later product Attempts are often made to give wood vinegar the flavor of that made from wine, by adding acetic ether, wine, Ac, but never with complete effect The best disguise is obtained by mixing in some highly flavored Orleans vinegar. Malt vinegar prepared by very slow fermentation in the air, acquires a peculiar ethe- reous odor, which cannot be imitated artificially, and hence persons accustomed to the flavor of such vinegar, by itself or in pickles, do not relish the vinegar made by the quick oxidizement process, either from malt or spirits. Even subjecting this vinegar to the action of rape accomplishes imperfectly the object in view. Were vinegar pure, it would be valued by its specific gravity alone, which at all strengths under 50 per cent gives exact indications ; but this is seldom the case, for ordinary vinegar contains more or less gluten and other organic matter, such as caramel, or burnt sugar, to color and flavor it besides sulphuric and possibly other acids. Hence the Excise have adopted the following plan of acetometry su^ested by Messrs. Taylor. When pure vinegar is saturated with quicklime, the liquid takes a density double of that due to the acetic acid present Thus, an acetate of lime of sp. gr. 1 -018, corresponds to a pure vinegar of 1 -009 ; but malt vinegar of that strength has its density raised to 1*014 by the gluten. When such vinegar is saturated with quicklime, the acetate acquires a specific gravity of 1-023, from which, if the five due to the gluten be deducted, the remainder, 1*018, will be double of the true density. Revenue proof vinegar, called No. 24, has, according to these gentlemen, the ACETIC ACID. Sp. gr. 1-0085, and contains of real acid 5 in 100. Da 1-0170 do. do. 10 do. Do. 1-0257 « do. do. 16 do. Do. 1-0320 do. do. 20 do. Do. 1-0470 do. do. 30 do. Do. 1-0680 do. do. 40 do. The acid of this table is the anhydrous, being stronger by about 15 per cent than that of my table given above. The chemical analysis of vineijar consists first in deter- mining the presence and proportion of foreign matter. With this view 600 grains of it should be evaporated by the heat of a chlor-calcium bath, the residuum weiglied and examined. If it be sour, sulphuric acid may be suspected, and its amount be ascer- tained by precipitation with nitrate of barytes, and weighing the washed and dried pre- cipitate. Every 118 parts indicate 49 of oil of vitrol ; but if saline sulphates be pre- sent their amount may be ascertained by igniting the above residuum and weighing what remains. The loss in ignition will be due to organic matter, acetates, and sul- phuric acid. If an alkaline acetate be present after ignition, the residuum may be an alkaline carbonate. Nitric acid is best detected by adding a few drops of a dilute sul- phate of indigo to the vinegar, and by boiling the mixture; when the blue will pass into a dirty brown yellow if nitric acid be present In common cases a ready mode of esti- mating the strength of the vinegar is wanted, and no reagent is better for the purpose than tlie bicarbonate of potash, two grains of which are equivalent to very nearly one of anhydrous acetic acid. To 100 or lOOO grs. of the vinegar in question we have only to add from a weighed parcel of pounded bicarbonate of potash, enough to produce neu- tralization by the test of litmus paper, and the half number of grains required denotes the number of grains of acetic acid in 100 or 1000 of the vinegar. Or a normal solution of the bicarbonate may be kept ready made, of which 1000 water grain measures contain 100 of the salt; then each 20 grain measures expended in neutralizing 1000 water grain measures of the vinegar denote one grain of real acetic acid. As the extrication of car bonic acid from the bicarbonate is apt however, in common hands to cause fallacies, I prefer ammonia as a general acidimetrical test of which 1000 water grain measures of specific gravity 0*992 neutralize exactly one atom of acetic acid; that is, 51 grains of the anhydrous, or 60 of the hydrate ; therefore after adding that test ammonia to the vinegar faintly reddened with litmus, out of a graduated glass tube, till the neutral tint of color be hit the number of water grain measures of test expended, being multiplied either by 61 or 60, will give for a product the per centage of anhydrous or hydrated acetic acid. This is the method I have pursued for very many years, and which gives results of perfect precision in a few minutes. Vinegar is so extensively employed as a condiment, that it should be of better quality than is commonly on sale in the United Kingdom, where it is almost always conta- minated with oil of vitriol. All our pickles participate in the same noxious ingre- dient The fumes of vinegar, and even its odor, as in the vinegar of the Three Thieves of Marseilles, were long supposed to be counteractive of contagion in sick rooms; but they are rather injurious, by covering unwholesome smells from want of due cleanliness and ventilation, and should never be relied upon. In combination with alumina, and also with oxide of iron, it is extensively used in the dyeing and printing of cotton, under the names of red liquor and iron liquor, as mordants for bright and dark colors. According to Dobereiner and Liebig, in the conversion of alcohol into acetic acid no carbonic acid is formed. 100 lbs. of alcohol consisting of 52*6 carbon -|- 12*9 hydrogen -f 34-5 oxygen, absorb from the air, in the process of acetification, 35*2 lbs. of oxygen, which abstract 4*4 lbs. of hydrogen from the alcohol, and thus generate 39*6 iW of water, leaving the substance called aldehyde (dehydrogenated alcohol), which consists of 52*6 carbon -f 8*6 hydrogen -f 68*4 oxygen. In practice we cannot obtain so much acid as the above, but the theoretical maximum serves as a beacon, and the nearer we can approach to it the better. About 3600 cubic feet of air contain 69 lbs. of oxygen, the quantity barely necessary for acetifying 100 lbs. of alcohol; but as the air is only partially stripped of that element, much more is needed, and this excessive current carries off some alcohol, aldehyde, and acetic acid, and so lessens the product I^ on the other hand, air be too sparingly supplied, volatile aldehyde is chiefly formed, which flies oflF, and leaves a mawkish putrefying liquor of no value. We may complete the preceding view of the production of acetic acid, by showing the relations which subsist between it and sugar, and starch, through the medium of alcohol— four correlative compounds, 100 lbs. of cane sugar are convertible into 100 lbs. of starch sugar or grape sugai*, by boiling it with sulphuric or tartaric acid, and abstract- ing the acid by means of chalk; and that weight of either kind of sugar is capable of » • ACETIC ACID. yielding by fermentation, 53-7 lbs. of alcohol. 100 lbs. of starch, if well saccharified, should afford fully 100 lbs. of starch sugar, and, therefore, 63-7 lbs. alcohol. Theue we the theoretical quantities, but they can nev^r be realized in practice. A quarter of good malt, weighing 320 lbs., contains by my experimenta 144 solid estract, which should yield, firs^ 69i alcohol ; and next 100 lbs. of acetic acid hydrate, equivalent to 17 times that weight of revenue proof vinegar -=» 170 gallons nearly. Before the process for pyroligneous acid, or wood vinegar, was known, there was only one method of obtaining strong vinegar practised by chemists ; and it is still followed by some operators, to prepare what is called radical or aromatic vinegar. This consists in decomposing, by heat alone, the crystallized binacetate of copper, commonly, but impro- perly, called distilled verdigris. With this view, we take a stoneware retort {fig. 1), of .1 size suited to the quantity we wish to oper- ate upon ; and coat it with a mixture of fire clay and horsedung, to make it stand the heat better. When this coating is dry, we introduce into the re- tort the crystallized ace- tate slightly bruised, but jTiV 1, very dry; we fill it as far as it will hold without spflhng when the beak is considerably inclined. We then set it in a proper furnace. We attach to its neck an adopter pipe, and two or three globes with opposite tubu- wres, and a last globe with a vertical tubulure. The apparatus is terminated by a Welter's tube, with a double branch ; the shorter issues from the last ?lobe, and the other dips into a flask filled with distilled vinegar. Everything being thus arranged, we lute the joinings with a putty made of pipeclay and linseed oil, and cover them with glue paper. Each globe is placed in a separate basin of cold water, or the whole may Be put into an oblong trough, through which a constant stream of cold water is made to flow. The tubes must be allowed a day to dry. Next dav we proceed to the distilla- tion, tempering the heat very nicely at the beginning, and increasing it by very slow degrees till we see the drops follow each other pretty rapidly from the neck of the retort, or the end of the adopter tube. The vapors which pass over are very hot, whence a se- ries of globes are necessary to condense them. We should renew, from time to time, the water of the basins, and keep moist pieces of cloth upon the globes; but this demands great care, especially if the fire be a little too brisk, for the vessels become, in that case, BO hot, that they would infallibly be broken, if touched suddenly with cold water. It is always easy for us to regulate this operation, according to the emission of gas from the extremity of the apparatus. When the air bubbles succeed each other with great ra- pidity, we must damp the fire. The liquor which passes in the first half hour is weakest; it proceeds, in some mea- sure, from a little water sometimes left in the crystals, which when well made, however, ought to be anhydrous. A period arrives towards the middle of the process when we see the extremity of the beak of the retort, and of the adopter, covered with crystals of a lamellar or needle shape, and of a pale green tint. By degrees these crystals are carri- ed into the condensed liquid by the acid vapors, and give a color to the product. These cr) stals are merely some of the cupreous salt forced over by the heat. As the process approaches its conclusion, we find more difliculty in raising the vapors; and we must then augment the intensity of the heat, in order to continue their disengagement. Finally, we judge that the process is altogether finished, when the globes become cold, notwith- standing the furnace is at the hottest, and when no more vapors are evolved. The fire may then be allowed to go out, and the retort to cool. As the acid thus obtained is slightly tinged with copper, it must be rectified before bringin? it into the market. For this purpose we may make use of the same apparatus, only substituting for the stoneware retort a glass one, placed in a sand bath. All the globes ought to be perfectly clean and dry. The distillation is to be conducted in the usual way. If we divide the product into thirds, the first yields the feeblest acid, and the third the strongest. We should not push the process quite to dryness, because there remain in the last portions certain impurities, which would injure the flavor of the acid. The total acid thus obtained forms nearly one half of the weight of the acetate employed, and the residuum forms three tenths ; so that about two tenths of the acid kave been decomposed by the heat, and are lost. As the oxyde of copper is readily reduced to the metallic state, its oxygen goes to the elements of one part of the acid, and fbnns water, which mingles with the products of carbonic acid, carbureted hydrogen, and ACETIC ACID. 9 carboEic oxyde gases which are disengaged : and there remains in the retort some chai- coal mixed with metallic copper. These two combustibles are in such a state of division, that the residuum is pyrophoric. Hence it often takes fire the moment of its being re- moved»from the cold retort. The very considerable loss experienced in this operation has induced chemists to try diflerent methods to obtain all the acid contained in the ace- tate. Thus, for example, a certain addition of sulphuric acid has been prescribed ; but, besides that the radical vinegar obtained in this way always contains sulphurous acid, from which it is difficult to free it, it is thereby deprived of that spirit called the jryro- aceticy which tempers the sharpness of its smell, and gives an agreeable aroma. It is to be presumed, therefore, that the preceding process will continue to be preferred for mak- ing aromatic vinegar. Its odor is often further modified by essential oils, such as those of rosemary, lavender, &c. 4. Pyroligneous ^cid, or Wood Vinegar.— The process for making this acid is founded upon the general property of heat, to separate the elements of vegetable substances, and to unite them anew in another order, with the production of compounds which did not exist in the bodies subjected to its action. The respective proportion of these products vaiies, not only in the diflerent substances, but also in the same substance, according as the degree of heat has been greater or less, or conducted with more or Jess skill. When we distil a vegetable body in a close vessel, we obtain at first the included water, or tnat of vegetation ; there is next formed another portion of water, at the expense of the oxy- gen and hydrogen of the body ; a proportional quantity of charcoal is set free, and, with the successive increase of the heat, a small portion of charcoal combines with the oxygen and hydrogen to form acetic acid. This was considered, for some time, as a peculiar acid, and was accoidingly called pyroligr.eous acid. As the proportion of carbon becomes preponderant, it combines with the other principles, and then some empyreumalic oil is volatilized, of little color, but which becomes thicker, and of a darker tint, always getting more loaded with carbon. Several elastic fluids accompany these diflTerent products. Carbonic acid comes over, but m small quantity, much carburreted hydrogen, and, towards the end, a considerable proportion of carbonic oxyde. The remainder of the charcoal, which could not be carried ofl'in these several combinations, is found in the retort, and preserves, usually, the form of the vegettible body which furnished it. Since mankind havo^ begun to reason on the diflerent operations of the arts, and to raise them to a level with scientific researches, they have introduced into several branches of manufacture a muliitude of improvements, of which, formerly, they would hardly have deemed them susceptible. Thus, in pa/tir a- lar, the process for carbonizing wood has been singularly meliorated, and in reference to the preceding observations, advantage has been derived from several products that for- merly were not even collected. The apparatus employed for obtaining crude vinegar from wood, by theagency of heat, are large iron cylinders. In this country they are made pEZ^T-rpZL, of cast iron, and are laid horizontally in the furnace ; in TXlAM.tZ? France, they are made of sheet iron riveted together, and they are set upright in the fire. Fig. 2 will give an ac- curate idea of the British plan, which is much the same as that adopted for decomposing pit coal in gas works, only that the cylinders for the pyroligneous acid manufacture are generally larger, being frequently 4 feet in diameter, and 6 or 8 feet long, and built horizontally in brickwork, so that the flame of one furnace may play around two ot them. It would probably answer better, if their size were brought nearer the dimensions of the gas-light retorts, and if the whole system of working them were assimilated to that of coal gas. The foiiowmg arrangement is adopted in an excellent esta- blishment in Glasgow, where the above large cylinders are 6 feet long, and both ends of them project a very little bevond the brickwork. One end has a disc or round plate of cast iron, well fitted, and firmly boiled to It, from the centre of which disc an iron tube, about 6 inches diameter, proceeds and enters, at a right angle, the main tube of refrigeration. The diameter of this tube may be • °^ii i" ^^ inches, according to the number of cylinders. The other end of the cylinder is called the mouth of the retort ; this is closed by a disc of iron, smeared round its edge by clay lute, and secured in its place by fir wedees. The charge of wood for such a cylin- der IS about 8 cwt. The hard woods— oak, ash, birch, and beech— are alone used ; fir does not answer. The heat is kept up during the day-time, and the furnace is allowed to cool during the night. Next morning the door is opened, the charcoal removed, and a new cliarge of wood is introduced. The average product of crude vinegar called pvrolis- ncous a^id, is 35 gallons. It is much contaminated with tar, is of a deep brown' color. 10 ACETIC ACID. and has a sp. gr. of 1'025. Its total weight is therefore about 300 lbs., but the residuarr charcoal is found to weigh no more than one fifth of the wood employed ; hence nearly one half of the ponderable matter of the wood is dissipated in incondensable gases. Count Rumford states, that the charcoal is equal in weight to more than four tehths of the wood from which it is made. The count's error seems to have arisen from the slight heal of an oven to which his wood was exposed in a glass cylinder. The result now given, is the experience of an eminent manufacturing chemist. The crude pyroligneous acid is rectified by a second distillation in a copper still, in the body of which about twenty gallons of viscid tarry matter are left from every 100. It has now become a transparent brown vinegar, having a considerably empyreumatic smell, and a sp. gr. of 1-013. Its acid powers are superior to those of the best household vinegar, in the proportion of three to two. By redistillation, saturation with quick- lime, evaporation of the liquid acetate to dryness, and conversion into acetate of soda by sulphate of soda, the empyreumatic matter is so completely dissipated, that on decom- posing the pure acetate of soda by sulphuric acid, a perfectly colorless and grateful vine- gar rises in distillation. Its strength will be proportionable to the concentration of the decomposing acid. The acetic acid of the chemist may be prepared also in the following modes: — 1. Two parts of fused acetate of potash, with one of the strongest oil of vitriol, yield, by slow distillation from a glass retort into a refrigerated receiver, concentrated acetic acid. A small portion of sulphurous acid, which contaminates it« may be removed by redistillation from a little acetate of lead. 2. Or four parts of good sugar of lead, with one part of sulphuric acid, treated in the same way, afford a slightly weaker acetic acid. 3. Gently calcined sulphate of iron, or green vitriol, mixed with sugar of lead, in the prep ortion ol 1 of the former to 2^ of the latter, or with acetate of copper, and carefully distilled from a porcelain retort into a cool receiver, may be also considered an economical process. But that with binacetate of copper above described, is preferable to any of these. The maniifacture of pyroligneous acid is conducted in the following way in France. Into large cylindrical vessels {fig. 3) made of riveted sheet iron, and having at their top and side a small sheet iron cylinder, the wood intended for making charcoal is introduced. To the upper part of this vessel a cover of sheet iron, b, is adapted, which is fixed with bolts. This vessel, thus closed, represents, as we see, a vast retort. When it is prepared, as we have said, it is lifted by means of a swing crane, c, and placed in a furnace, d (Jig. 4), of a form relative to that of the vessel, and the opening of the furnace is covered with a dome, e, made of masonry or brickwork. The whole being thus arranged, heat is ap- plied in the furnace at the bottom. The moisture of the wood is first dissipated, but by degrees the liquor ceases to be transparent, and becomes sooty. An adopter tube. A, is then fitted to the lateral cylinder. This adopter 0/<— ^"a^^^sP^ Tf^a^ enters into another tube at the same degree of inclination OTT ]'' 1 J^^ which commences the condensing apparatus. The means ^—T U U r*l of condensation vary according to the localities. In cer- tain works I hey cool by means of air, by making the vapor pass through a long series of cylinders, or some- times, even, through a series of casks connected together ; but most usually water is used for condensing, when it can be easily procured in abundance. The most simple apparatus employed for this purpose consists of two cy linders, r, f {fig. 4), tho one within the other, and which leave between them a suflUcient space to allow a considerable body of water to circulate along and cool the vapors. This double cylinder is adapted to the distilling vessel, and placed at a certain inclina- tion. To the first double tube, F, F, a second, and ACETIC ACID. U Jt i. I «ometimes a third, entirely similar, are connected, which, to save space, return upon them- fjelves in a zigzag fashion. The water is set in circulation by an ingenious means now adopted in many different manufactories. From the lower extremity, g, of the system of condensers, a perpendicular tube rises, whose lens^lh should be a little more than the most elevated point of the system. The water, furnished by a reservoir, l, enters by means of the perpendicular tube through the lower part of the system, and fills the whole space between the double cylinders. When the apparatus is in action, the vapors, as they condense, ra.se the temperature of the water, which, by the column in L G, is pressed to the upper part of the cylinders, and runs over by ihe spout k. To this point a very short tube is attached, which is bent towards the ground, and serves as an overflow. The condensing apparatus is tenninated by a conduit in bricks covered and sunk in the ground. At the extremity of this species of gutter is a bent tube, e, which dis- charges the liquid product into the first cistern. When it is* full, it empties itself, by means of an overflow pipe, into a great reservoir : the tube which terminates the gutter plunges into «he liquid, and thus intercepts communication with the inside of the appa- ratus. The Qisengaged gas is brought back by means of pipes m l, from one of the sides of the conduit to the under part of the ash pit of the furnace. Tbese pipes are furnish- ed with stopcocks m, at some distance in front of the furnace, for the purpose of regula- ting the jet of the gas, and interrupting, at pleasure, communication with the inside of the apparatus. The part of the pipes which terminates in the furnace rises perpendicu- larly several inches above the ground, and is expanded like the rose of a watering can, n. The gas, by means of this disposition, can distribute itself uniformly under the vessel, with- out suffering the pipe which conducts it to be obstructed by the fuel or the ashes. The temperature necessary to effect the carbonization is not considerable: however, at the last it is raised so high as to make the vessels red hot ; and the duration of the process is necessarily proportional to the quantity of wood carbonized. For a vessel which shall contain about 5 meters cube (nearly 6 cubic yds.), 8 hours of fire is sufficient. It is known that the carbonization is complete by the color of the flame of the gas : it is first of a yellowish red ; it becomes afterwards blue, when more carbonic oxyde than carbonic hydrogen is evolved ; and towards the end it becomes entirely white, — a circum- stance owing, probably, to the furnace being more heated at this period, and the combustion being more complete. There is still another means of knowing the state of the process, to which recourse is more frequently had ; that is the cooling of the first tubes, which are not surrounded with water : a few drops of this fluid are thrown upon their surface, and if they evaporate quietly, it is judged that the calcination is sufficient. The adopter tube is then unluted, and is slid into its junction pipe; the orifices arc immediately stopped with plates of iron and plaster loam. The brick cover, e, o^ the furnace is first removed by means of the swing crane, then the cylinder itself is lifted out and replaced immediately by another one previously charged. When the cylinder which has been taken out of the furnace is entirely cooled, its cover is removed, and the charcoal is emptied. Five cubic meters of wood furnish about 7 chaldrons (voies) and a half of charcoal. (For modifications of the wood-vinegar apparatus, see CharcoaIi and Pyroligneous Acip.) The different qualities of wood employed in this operation give nearly similar pro- ducts in reference to the acid ; but this is not the case with the charcoal, for it is better the harder the wood ; and it has been remarked that wood long exposed to the air fur- nishes a charcoal of a worse quality than wood carbonized soon after it is cut. Having described the kind of apparatus employed to obtain pyroligneous acid, I shall now detail the best mode of purifying it. This acid has a reddish brown color ; it holds in solution a portion of empyreumatic oil and of the tar which were formed at the same time, another portion of these products is in the state of a simple mixture : the latter may be separated by repose alone. It is stated above, that the distilling apparatus terminates in a subterranean reservoir, where the products of all the vessels are mixed". A common pump communicates with the reservoir, and sinks to its very bottom, in order- that it may draw off only the stratum of tar, which, according to its greater density, occupies the lower part. From time to time the pump is worked to remove the tar as it is deposited. The reservoir has at its top an overflow pipe, which discharge^ the clear* est acid into a cistern, I'rom which it is taken by means of a second pump. The pyroligneous acid thus separated from the undissolved tar is transferred from this cistern into large sheet iron boilers, where its saturation is effected eiiher by quicklime or ])y chalk, the latter of which is preferable, as the lime is apt to take some of the iai into combination. The acid parts by saturation with a new portion of the tar, which is removed by skimmers. The neutral solution is then allo\«ed to rest for a sufficient time to let its clear parts be drawn off by decantation. The acetate of lime thus obtained indicates by the hydrometer, before being mixed with the waters of edulcoration, a degree corresponding to the acidimetric degree of the acid IS ACETIC ACID. employed. This solution must be evaporated till it reaches a specific gravity of I-IM (15° Baume), after which there is added to it a saturated sohition of sulphate of soda. The acids exchange bases ; sulphate of lime precipitates, and acetate of soda remains in solution. In some manufactures, instead of pursuing the above plan, the sulphate o/ soda is dissolved in the hot pyroligneous acid, which is afterwards saturated with chalk or lime. By this means no water need be employed to dissolve the sulphate, and ac- cordingly the liquor is obtained in a concentrated form without evaporation. In both modes the sulphate of lime is allowed to settle, and the solution of acetate of soda is de- canted. The residuum is set aside to be edulcorated, and the last waters are employed for washing fresh portions. The acetate of soda which results from this double decomposition is afterwards evap- orated till it attains to the density of 1*225 or 1-23, according to the season. This so- lution is poured into large crystallizing vessels, from which, at the end of 3 or 4 days, according to their capacity, the mother waters are decanted, and a first crjstallizatioQ is obtained of rhomboidal prisms, which are highly colored and very bulky. Their facettes are finely polished, and their edges very sharp. The mother waters are submitted to successive evaporations and crystallizations till they refuse to crjstallize, and they are then burnt to convert them into carbonate of soda. To avoid guesswork proportions, which are always injurious, by the loss of time which they occasion, and by the bad results to which they often lead, we should determine experimentally, beforehand, the quantities absolutely necessary for the reciprocal dccom- IKJsition, especially when we change the acid or the sulphate. But it may be remarked that, notwithstanding all the precautions we can take, there is always a notable quantity of sulphate of soda and acetic acid, which disappear totally in this decomposition. This arises from the circumstance that sulphate of soda and acetate of lime do not completely decompose each other, as I have ascertained by experiments on a very considerable scale ; and thus a portion of each of them is always lost with the mother waters. It night be supposed that by calcining the acetate of lime we could completely destroy its empy. reumatic oil ; but, though I have made many experiments with this view, I never could abtain an acetate capable of affording a tolerable acid. Some manufacturers prefer to make the acetate of soda by direct saturation of the acid with the alkali, and think that the higher price of this substance is compensated by the economy of time and fuel which it produces. The acetate of soda is easily purified by crystallizations and lorrefaction ; the latter process, when well conducted, freeing it completely from every particle of tar. This torrefaction, to which the name of fusion may be given, requires great care and dexterity. It is usually done in shallow cast iron boilers of a hemispherical shape. During all the time that the heat of about 500° Fahr. is applied, the fused mass must be diligently work- ed with rakes; an operation which continues about 24 hours for half a ton of materials. We must carefully avoid raising the temperature so high as to decompose the acetate^ and be sure that the heat is equally distributed ; for if any point of the mass enters into decomposition, it is propagated with such rapidity, as to be excessively difficult to stop its progress in destroying the whole. The heat should never be so great as to disengage any smoke, even when the whole acetate is liquefied. When there is no more frothing up, and the mass flows like oil, the operation is finished. It is now allowed to cool in a body, or it may be ladled out into moulds, which is preferable. When the acetate is dissolved in water, the charcoaly matter proceeding decomposition of the tar must be separated by filtration, or by boiling up the the specific gravity 1*114, when the carbonaceous matter falls to the bottom, porating the clear liquor, we obtain an acetate perfectly fine, which yields crystals on cooling. In this state of purity it is decomposed by sulphuric acid, in order to separate its acetic acid. This last operation, however simple it appears, requires no little care and skill. The acetate of soda crystallized and ground is put into a copper, and the necessary quantity of sulphuric acid of 1*842 (about 35 per cent, of the salt) to decompose almost, but not all, the acetate, is poured on. The materials are left to act on each other ; by degrees the acetic acid quits its combination, and swims upon the surface ; the greater part of the resulting sulphate of soda falls in a pulverulent form, or in small granular crystals, to the bottom. Another portion remains dissolved in the liquid, which has a specific gravity of 1-08. By distillation we separate this remainder of the sulphate, and finall> obtain acetic acid, having a specific gravity of 1*05, an agreeable taste and smell, though towards the end it becomes a little empyreumatic, and colored; for which reason, the last portions must be kept apart. The acid destined for table use ought to be distilled in an alembic whose capital and condensing worm are of silver ; and to make it very fine, it may be afterwards infused over a little pure animal charcoal — the well-washed residuum of the Prussian-blue-works black. from the liquor to On eva- beautiful '] ACTINISM. n An excise duty of 2d. is levied on every gallon of the above proof vinegar. Its strength is not, however, estimated directly by its specific gravity, but by the specific gravity which it assumes when saturated with quicklime. The decimal fraction of the specific gravity of the calcareous acetate is very nearly the double of that of the pure vinegar; or, 1*009 in vinegar becomes 1*018 in acetate of lime. The vinegar of malt contains so much mucilage or gluten, that when it has only the same acid strength as the above, it has a density of 1.0014, but it becomes only 1*023 when converted into acetate of lime : indeed, 0*005 of Us density is due to mucilaginous matter. This fact shows the fallacy of trusting to the hydrometer for determining the strength of vinegars, which may be more or less loaded with vegetable gluten. The proper test of this, as of all other acids, is, the quantity of alkaline matter which a given weight or measure of it will saturate. For this purpose the bicarbonate of potash, commonly called, in the London shops, carbonate, may be employed very conveniently. As it is a very uniform substance, and its atomic weight, by the hydrogen radix, is 100*584, while the atomic weight of acetic acid, by the same radix, is 51*563, if we estimate 2 grains of the bicar- bonate as equivalent to 1 of the real acid, we shall commit no appreciable error. Hence, a solution of the carbonate containing 200 grains in 100 measures, will form an aceti- meter of the most perfect and convenient kind ; for the measures of test liquid expended in saturating any measure, — for instance, an ounce or 1000 grains of acid, — will indi- cate the number of grains of real acetic acid in that quantity. Thus, 1000 grains of the above proof, would require 50 measures of the acetimetrical alkaline solution, showing that it contains 50 grains of real acetic acid in 1000, or 5 per cent. It is common to add to purified wood vinegar, a little acetic ether, or caramelized (burnt) sugar to color it, also, in France, even wine, to flavor it. Its blanching effect upon red cabbage, which it has been employed to pickle, is owing to a little sulphurous acid. This may be removed by redistillation with peroxyde of manganese. Indeed, Stoltze professes to purify the pyroligneous acid solely by distilling it with peroxyde of manganese, and then digesting it with bruised wood charcoal ; or by distilling it with a mixture of sulphuric acid and manganese. But much acid is lost in this case by the for- mation of acetate of that metal. Birch and beech afford most pyroligneous acid, and pine the least. It is exclusively employed in the arts, for most purposes of which it need not be very highly purified. It is much used in calico printing, for preparing acetate of iron called Iron Liquor, and acetate of alumina, called Red Liquor ; which see. It serves also to make sugar of lead ; yet when it contains its usual quantity, after rectification of tarry matter, the acetate of lead will hardly crystallize, but forms cauliflower concretions. This evil may be remedied, I believe, by boiling the saline solution with a very little nitric acid, which causes the precipitation of a brown granular substance, and gives the liquor a reddish tinge. The solution being afterwards treated with bruised charcoal, becomes colorless, and furnishes regular crystals of acetate or sugar of lead. Pyroligneous acid possesses, in a very eminent degree, anti-putrescent properties. Flesk steeped in it for a few hours may be afterwards dried in the air without corrupting; but it becomes hard, and somewhat leather-like : so that this mode of preservation does not answer well for butcher's meat. Fish are sometimes cured with it. See Pvro-acetic Spirit; Pyroxilic Ether; Pyroxolic Spirit ; Pyroligneous Acid and Vinegar. In 1838, 2,628,978 gallons of vinegar paid duty in England; in 1839, 2,939,665; and in 1840, 3,021,130; upon which the gross amount of dutv was, respectively, 21,908/. 3«. ; 24,448/. 17s. &d. ; and 25,978/. 12s. 9« ^'^ohol "«>• be concentrated when a «u table heat IS employed. This economical method is particularly appfieTbirh, "l^ taming alcohol for tfie preparation of varnishes. When the alcohoHs to serve fOT tl e bird. rr\'trf *" ^^r,^ "^ -Ji'ti""""". f-^™ "e^tain matters dissolved out of wL„ ,5, ■^ .1? ."' """^ bkewise be strengthened, as Sommering has ascertained. Tome iito crtae w ,r?^'l? "'.' "^l^' '' '"""<' "'"^ "'"> " ^addfr whfch doe "not t"i:cI "rlfutl^S !: 1 1 :'" T^^""^ ""<' """> a^tated tillThe^t rdlsSveA msmmmmm salts of strLt a ?n aTcohof btrn S' - ■"" '" '« ^"""l """" ">* ^"'•'""™ »' 'be green, lime redSilh, and btyu ye^'ot "''""""' """"' ""'"' "' ""^f" ''"^ '"'^'^ tlieJe eSst,fn"gAtttf with Mn'"'"' "",'' %«T'3f ?«»» »' ™'»">e are the result ; decreasing w.'^^I a°g?SLr nroiforffon'S J? " "C »''>"'» ap^ ,« "f ^ater, and thence for each determh a e pronVrC of 'wrf'^^'J *''!^ ^H «P^«ifi« Suavity be ascertained this is done, ^c mavT/meanV and water that are mixed together. When water, detemine Z etiengSi of 1^^^ e^^^^^^^^^ ^T'"^' ^^^'^*- '^^-- an arbitrary graduation oorrZ^LP K ' }■ ^>' ^ ^""^^^ of specific gravities or by determine t^.fperceXe o^^^^^^^^^^^^^ ^f "'" I'^r^'l''^ ^^J^^^^' «"^ *^"« ^« ^4 areometer inte'JiderforThisusehrs^b^^^^^ ^H^uHty. aI scale of it issoffraduatSTat fsfPaZ^^^^ the percentage of anhXus ^16^01 fn I ' '''''^•' f f ^ immediately scale graduated accorfc to fhr^ V ^'""T '^''^^'* ^^ "'«1""^« ^^ «»e liquid. The alcohf Imeter of RichS \nd that W ?1 ? ^^ ^T ^^•'^^"! ^^ ^^'^^'*' constitutes the Tralles and Gay Lussac ' ^ ^ percentage in volume, the alcoliolmeter of thetefr,^ wt;f iSit^^^^^^^^^ jr"'- r '^ -^^i ™^^*' ^^ >« ™-t, Tralles has constructed new taW^^"n^^^^^ percentage by volume, proportion is given by volLe ^^d afrdro?"rT^?-^^'^^ 5^.^^^'^'"' ^'° ^''''^^^ ^he 60° Fahr., has a spccilfc craWtv of n^QJo^ ^^'S^""^ l^ ^''""'^^ ^""^ ^he basis which at or a specific grality of O^oifj^ Gilpin\alcolfol of 0^-825 containH? 6 ni^^^^^^^ f '^' temperature of 60° Fahi According to the expS^ts of Tr!ll ^ ^I 7^"^' ^^'*"'^y^''^"« «^^«^^ + 37 C. wiTh tolerabiruniTom tv fl^^^^^^^^ alcohol contracts between-260 C. and volume of the alcohol. In tTe ^lowi 'rt 'l^'^-';'' "^r""'^''^"" ^^ ^'^'^^^ ^^ ^he wards from the boiling point by Gay Tusfac ' <^««tractions are reckoned down- I!: fW- ALCOHOL. Temp. Yolame. Temp. 48°-4 43°-4 88°-4 33°-4 28°-4 Yolame. Temp. Volume. 78*-4 73'-4 68°-4 63°-4 68*-4 53°-4 1000- 994-4 988-6 982-6 976-7 970-9 966-8 960-0 964-4 948-9 943-6 23°-4 18°-4 18° -4 8°-4 988-6 934-0 929-3 924-6 9190 empyreumatic oil, and carbon ; afeorfine ?o the deip^^rS h' if ^^ naphthaline, these producU vary. Anhydrous alcohol is a n„„5I^^!. "^ ''«'" "d »«*"« of the tube composed by a powerful voitaic battery llcohoXrn • ♦■" ' e ectr city, but is de- mto carbonic ^id and water; Te water be?n„),^ •?.,*''*.?'''''*'''>'■>« A*™ parte of alcohol contain 6 of Cro^eXfeo^"S t'" '^ 'P'?*- ^"'''^ *« combustion is accompanied with VS»f Tilf J^i?*^ '""«'•• I" oxymn the en,aUtube,powerfuI1^1^L Wief^U'dllt'' ""' "'""*' ^""''^ t^™"gh • hea^rcSi:i;'S'el^r:S':ftilttt^^^^^^^ ide of uranium, wide of tin (tSse six hod;., T^" P"''''^i'l*»'^ "=<>'>»'». Proto/- oxalates in a crucibleX or finely ^wderedmaL.„^^ '^""""^f ^^ '^"'^'"^ »f their pUce. «>d continues as^ong as (hrs^Sus^ri^rSts''"''"^'' '"■"'"«««» »<*" water being considered .,' 6C^ FaKtave 7^^ S"„f S^^^ "' '"' »?-". Alcoholmetrical Table of Tralles. Alcahol in 100 measure! of spirit. 1 s t 4 ft € 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 Specific gravity ■t 60O Fahr. Diflference of the ep. gr. 9991 9976 9961 9947 9933 9919 9906 9893 9881 9869 9857 9845 9834 9823 9812 9802 9791 9781 9771 9761 9751 9741 9731 9720 9710 9700 9689 9679 9668 9657 9646 9634 9622 9609 Alcohol in 100 measures of •pirit. 15 15 14 14 14 13 13 12 12 12 12 11 11 11 10 U 10 10 10 10 10 10 11 10 10 11 10 11 II 11 12 12 13 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 Specific gravity at 60O Fahr, 9315 9295 9275 9254 9234 9213 9192 9170 9148 9126 9104 9082 9059 9036 9013 8989 8965 8941 8917 8892 8867 8842 8817 8791 8765 8739 8712 8685 8658 8631 8603 8575 8547 8518 Difference of the Bp. gr. 20 20 20 21 20 21 21 22 22 22 22 22 23 23 23 24 24 24 24 25 25 25 25 26 26 26 27 27 27 27 28 28 28 29 \ ALCOHOL. Alcoholmetrical Table of Tralles {continued). 21 Alcohol in 100 measures of spirit. 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 Specific gravity at 60O Fahr. 9596 9583 9570 9556 9541 9526 9610 9494 9478 9461 9444 9427 9409 9391 9373 9354 9335 Difference of the sp. gr. 13 13 13 14 15 15 16 16 16 17 17 17 18 18 18 19 19 Alcohol in 100 measures of spirit. 85 86 87 88 89 ^ 91 92 93 94 95 96 97 98 99 100 Specific gravity at eO" Fahr. 8488 8458 8428 8397 8365 8332 8299 8265 8230 8194 8157 8118 8077 8034 7988 7939 Difference of the sp gr. 30 30 30 31 32 33 33 34 35 36 37 39 41 43 46 49 Remarks on the preceding Table of Mcohol. gravty of the mixtnrs^ Sv ti,. .™»c '? ^ .^ "" "»y determinate specific fnd the product r?henumb« of ™f„^^ pure alcohol, that is, by 7939, gravity multiplied by 100 rili tC ^' f "~''°' '\^ """"y Po^-xls as the specific 40 measures of ^coholTX'nce there" i!^""::;!:;" "'^ SSlOspecific grayity, the?e arc 7939 + 40 = 31-756 Dound., of «V„h^f a •^„„"' ''''O" P°""'ls of this spirit n«cifit gravity 3™97undsoLtt"'Lrcon!aV^" •"""" "' '"« '"^'^ »' "-'^lO .ri^v«^K:'r'z1t%tSrl^V6"'F^ten^^^ alcohol for the soecific «a^t « ,^L. j^'' !''* [""""""g taWe gives the per centage of For example -Twe have a ^S"^'?'"^ '" ">« r^^-^P^J'-S tempcAtnres. ^ 0-9342, the \L^\ p4enUs 4Wr c"ent J.l l' ,'^ ^''^\ ^""'^ ^^^"8'= 8™"'? » temperature is equSl o he IpS J^i,'''VaiT^^^ 'hat ;^:f::::^^_Thi^ble .ay a-soV tpPfo? tf^'ig^ ^rS^-th'STr ani Alcohol per cent. Temperature. 5 10 15 20 25 30 S5 40 45 50 55 «0 65 70 75 80 85 30° F, 9994 9924 9868 9823 9786 9753 9717 9671 9615 9544 9460 9368 9267 916-2 9046 8925 8798 8663 8517 35° F, 9997 9926 9869 9822 9782 9746 9707 9658 9598 9525 9440 9347 9245 9138 9021 8899 8771 8635 8486 40» F. 45« P. 9997 9998 9926 9926 9868 9867 9820 9817 9777 9772 9738 9729 9695 9684 9644 9629 9581 9563 9506 9486 9420 9399 9325 9302 9222 9198 9113 9088 8996 8970 8873 8847 8744 8716 8606 8577 8455 8425 50*' F, 9997 9925 9865 9813 9766 9720 9672 9614 9546 9467 9378 9279 9174 9003 6944 8820 8688 8547 8395 55<» P. Alcohol per cent. Temperature 60« P. 9994 9922 5 9861 10 15 9807 9759 20 9709 25 9659 30 9599 35 S»528 40 9447 45 9356 50 9256 55 9150 60 90S8 65 8917 70 8792 75 8659 80 8517 85 8363 90 I 9991 9919 9857 9802 9751 9700 9646 9583 9510 9427 93.15 9234 9126 9013 8892 8765 8631 8488 8332 65«» P. 9987 9915 9852 9796 9743 9690 9632 9566 9491 9406 9313 9211 9102 8988 8866 8738 8602 8458 8300 70» p 9991 9909 9845 9788 9733 9678 »618 9549 9472 9385 9290 9187 9076 8962 8839 8710 8573 8427 8268 75«» P 9976 9903 9839 9779 9722 9065 9603 9532 9452 9364 9267 9163 9051 8936 8812 8681 8544 8396 8236 I lli 22 ALCOHOL. !!!!?• ^.^^^ l^'rr.^ ^^ ^^ ^*^^ computation for the intervals. It is evident from in- spection that a difference of 5° Fahr. in the temperature changes the specific -ravity ol H fi-?*^r u ** '^'ff^i'ence nearly equal to 1 volume per cent, of alcohol ; thus at 35" ana »o fahr. the very same specific gravity of the liquor shows nearly 10 volumes oer cent. 01 alcohol more or less ; the same, for example, at 60 and 40 per cent. • |/*® *™P°'"}*"p6 of extreme accuracy in determining the density of alcoholic mixtures *^i t V"^^^^ Kingdom, on account of the ^real revenue derived from them to the Slate and their consequent high price in commerce, induced the Lords of the Treasury a few years ago to request the Royal Society to examine the construction and modeof applyinsr Uie instrument now in use for ascertaining and charging the duty on spirits. This instru- ment, which is known and described in the law as Sikes's hydrometer, possesses, in many respects, decided advantages over thpse formerly in use. The committee of the Rov^ feociety state, that a definite mixture of alcohol and water is as invariable in its value as absolute alcohol can be; and can be more readily, and with equal accuracy, identified by that only quality or condition to which recourse can be had in practice, namely specific gravity The committee further proposed, that the standard spirit be that which consisting of alcohol and water alone, shall have a specific gravity of 92 at the temperature of 62° Fahr., water being unity at the sau.e tempem7ure • or in other ZZX^l:' ^'^ '' '^ "^^^' ToV ^' M '' - ^^^^ ^-^^ '^ waTeVaT'ti: ^Ime This standard is rather weaker than the old proof, which uas J4, or 0923 • or in the proportion of nearly M gallon of the present prci)f spirit per^cent The Drowsed ^1e hu^nteZ'fT^ "fi '" ^^"^ '^^ ^^^^"^'°" «^ ^^^^"^'^ 5 ««t «Pon an'arbitraTy scaJe, but m terms of specific gravity at the temperature of 62°. the slTTenl7h' nfT -r^^ J^' construction of an equation table, which shall indicate ine same strength of spirit at every temperature. Thus in standard spirit at 62° the hydrometer would indicate 920, which in this table would give prcK,f Sit If that whtV'h"' ""'"''^Y \^^' '^' hydrometer would indicate^some htherC^berVbu rhould stn?lfvT^'"'r ^" ^ T^l' ^.^'-^ '^' temperature as indicated by the thermometer should stiU give proof or standard spirit as the result. sm-rh'^bv^nf nnnV^""''*^^^' ^" ^^^' ^"^ V^' ^^^" ^^^^^^ "°^ ^0 express thequality of the ZlLrl «"7.^""»^" over or under proof, but to indicate at once the number of gallons of tSus instead 0?"'''""^^"' or equivalent to, 100 gallons of the spirit under examinat on. uoder' iroof t fnZ"! ^■^'''' ^'^^M'' ^''^^'''^ '^ '''''^'' ^^3 ; and in place of 35-4 unaer proot, to insert its diflference to 100, or 646 as^lo^W^fh". h?if r^-^-?f '"'^^ *** recommend a second table to be constructed, so bulk of 1^0 tiw «['/r' f 7J T^Hr'^ ^' ^"y temperature, relative to a standard anv ciLn t^rfnir t T-r' ^" ^^' l^^^^ ^ 'P'""" '"^^^^ ^^^ diminished in volume, at snfrifwhUT^f '^' V P" ^^" •' ^^' ^''^^P'^' ^^"l'^ ^^ expressed by 99-3 ; and a ^Wh^n f increased at any given temperature 0-7 per cent , by 100-7. When a sample of spirit, therefore, has been examined by the hydrometer and erer^ureVn^^^^^^ ''t' k' "I" '''' f'^ '^"^ P^°P«^^'°» ^' ''^^^^'^ «Pi"t at tSeobJerved Sard tP^nn/r f ""^ ^^^ /^hauge of bulk of such spirit from what it would be at the fsD t?? of 8240 mn* ?"'' ?' i^' temperature of 51°, and with an indication &.si fail fn d ?' ?*^^!lT! °^„'^^ T"^ ""^^'- examination would be shown by the Sond ti J^ >^ ^^''f ^° ^^^*^ ?^^^T «<^«^«»dard spirit of that temperature ; and by the 6? or fn l.« t '^'l^PPl" iafo^^'^. ^^^^'^^ «^ ^^« '^"^^ sP^^t would become 100 at dnfv"^f^ '^ is considered that neither of these tables can alone be used for charging the ^o-^^i inn u^"" """^ f P"^'" '^^ ^^'^"^^ "l^^^^i^y *>^ spirit of a specific gravity of 092 at ^nnifdio^" .• w^^?*""^' or weaker spirit at temperat.ires above or below 62°), it is Xi on f l'fr^'^\l\^^^^ ^ ^^''^ y^^^'' combining the two former, and expressing this ^n riUn inn ^?i f 'iP'''' "f ^ inspection it shall indicate the proportion of standard tK„r tv "^i "f^^u *^** «nder examination in its then present state. In this table the quantities should be set down m the actual number of gallons of standard spirit at 62°, equivalent to 100 of the spirit under examination; and the column of quantities may be expressed by the term value, as it in reality expresses the proportion of the only «ci!} \'"u''^"*'^ P'^'^^i- ^' *^^ ^»" ^ ^^e only table absolutely necessary to be nsed with the instrument for the purposes of the excise, it may, perhaps, be Uiought unnecessarj to print the former two. ^ ' "*"«sui ♦ i f \ 1 ALCOHOL. 28 The following specimen table has been given by the committee : Temperature 45«. | remperature 7i .«. Indication.* Strength. Value. 1 Indication. Strength. Valae. 9074 114-5 8941 114-5 7 114-3 4 114-3 9 114-2 5 114 2 81 114-0 8 114-0 3 113-9 9 113-9 5 113-7 52 113-7 6 113 6 3 113 '6 9 113-4 6 113-4 90 113-3 7 113-3 3 113-1 9 113-1 _ The mixture of alcohol and water, taken as spirit in Mr. Gilpm's tables, is that of which the specific gravity is 0-825 at 60° Fahr., water being unity at the sSne temp^. ature. The specific gravity of water at 60° being 1000, at 62° it is 99,981. Hence in order to compare the specific gravities given by Mr. Gilpin with those which would re- mtt t'Lis:d'ryt9!9ir'' """'"" "' '^ ^' ''^''' ""' ""^*^' ^"^ "^^ ''"^'^ ^^-^^» Table of the Specific Gravities of different Mixtures, by Weight, of Alcohol and Water. nue^^S kite^'"^^''*^"'^' constructed by Mr. GUpin, for the use of the British Reve^ I- Deg. 30 35 40 4$ 50 55 60 65 70 75 80 85 90 95 10<) Pure Alcohol 100 Alcohol 5 Water. )-838d6 •83672 •83445 •83214 •82977 •82736 •82500 •82262 •82023 •81780 •81530 •81291 •81044 ■80794 •80548 0^84995 •84769 •84539 •84310 •84076 •83834 •83599 •83362 •83124 •82878 •82631 •82396 •82150 •81900 •81657 100 Alcohol 10 100 Alcohol 15 Water. Water 0-85957 •85729 •85507 ■85277 •85042 84802 84568 84334 84092 83851 83603 83371 83126 82877 82639 100 Alcohol 20 Water, Tenperattire, Falir. 85 40 45 90 53 60 65 70 75 80 85 90 95 100 100 Alcohol 55 0-86825 •86587 •86361 •86131 •85902 •83664 •85430 •85193 •84951 •84710 •84467 •84343 •84001 •83753 •83513 0^87585 •87357 •87184 •86905 •86676 •86441 •86208 •85976 •85736 •85496 •85248 •85036 •84797 •84550 •84038 100 Alcohol 25 Water. 100 Alcohol 60 Water. Water 0-91449 •91241 •91020 •90812 •90596 •90367 •90144 •89920 •89695 •89464 •89225 •89043 •88817 •88588 83571 0-91847 •91640 •91428 91211 •90997 •90768 •90545 •90328 •90104 -89872 •89639 •89460 •89230 •89003 887691 0-88282 ■88059 •87838 87613 87384 87150 66918 86686 86451 86212 85966 85757 85518 85272 85031 100 Alcohol 30 Water. 0-88921 •88701 •88481 •88^255 •68030 •87796 •87569 •87337 •87105 •86864 •86622 •86411 •86172 •85928 •85688 100 Alcohol 35 Water 0-89511 -89294 •89073 •88849 •88626 •88393 •88169 •67938 •87705 •87466 •87228 •87021 •86787 •86542 •86302 100 Alcohol 65 Water. 0^92217 •92009 •91799 •91584 •91370 •91144 90927 •90707 -90464 •90252 •90021 •89843 •89617 •89390 •89158 100 Alcohol 70 Water. 0-92563 92355 92151 91937 91723 91502 91287 91066 90847 90617 90385 90209 100 Alcohol 40 Water 1-90054 •89839 •89617 •89396 •89174 •88945 •887^20 •88490 •88254 •88018 •87776 •67590 87360 •57114 •86879 100 Alcohol 45 Water. 0^90558 90345 90127 89909 89684 89458 89232 89006 88773 68538 88301 881 -20 67889 87654 87421 100 Alcohol 75 Water. 100 100 Alcohol! Alcohol 80 85 Water. 89763 89536 0-92889 •92680 •92476 •92204 •92051 •91837 •91622 •91400 -91181 ■90952 •90723 •90558 90342 90119 89889 093191 •92986 •92783 •92570 •92358 •92145 •91933 •91715 •91493 •91270 •91046 •90882 •90688 •90443 •90215, 0-93474 •93274 •93072 •92859 •92647 •92436 •92^225 •92010 •91793 •91569 •91340 •91186 •90967 •90747 •905221 100 Alcohol 90 100 Alcohol 50 Water. )91023 -90811 -90596 •90380 •901 1)0 -89933 -89707 •89479 •89252 •89018 ■88781 -88609 •88376 •88146 •87915 0-93741 -93541 •93341 -93131 •92919 •92707 •92499 •92283 •92069 •91849 ■91622 •91465 91248 91029 90805 100 Alcohol 95 Water. Water. Water 0-93991 •93790 •93592 -9338-2 -93177 •92963 •92758 •92546 •9-2333 •92111 •91891 •91729 •91511 •91290 •91066 100 Alcohol 100 Water 0-94222 •940-25 •9.3827 •93621 •93419 -93208 -93002 ■92794 ■92580 92364 92142 91969 91751 91531 91310 •By specific gravity. I I 24 ALCOHOL. Table of the Specific Gravities of different Mixtures, &c. (amtinued). ature, r. 95 90 85 80 75 70 65 60 55 50 I« Alcohol Alcohol Alcohol Alcohol Alcohol Alcohol Alcohol Alcohol Alcohol Alcohol 1^ 100 100 100 100 100 100 100 100 100 100 ^ Water. Water. Water. Water. Water. Water. Water. Water. Water. Water. Deg. 30 0-94447 094675 0-94920 0-95173 095429 095681 0-95944 0-96209 096470 096710 35 •94249 •94484 -94734 •94988 •95246 •95502 •95772 •96048 •96315 •96579 40 •94058 •94295 ^94547 •94802 •95060 •95328 •95602 •95879 •96159 •96434 45 •93860 •94096 •94348 •94605 •94871 •95143 •95423 -95703 •95993 96180 50 •93658 •93897 •94149 ■94414 •W663 •94958 •95243 •95534 •95831 •90126 55 •93452 •93696 •93948 •94213 •94486 •94767 •95057 •95357 •95662 •95966 60 •93247 '93493 •93749 •94018 •&4296 •94579 •94876 •95181 95493 ■95804 65 •93040 •93285 •93546 •93822 ■94099 •94388 •94689 •95000 •95318 •95635 70 •92628 •93076 •93337 •93616 •93898 •94193 •94500 •94813 95139 •95469 75 •92613 •92865 •93132 •93413 •93695 •93989 •94301 •94623 94957 ■95292 80 ■92393 •92646 ■92917 ■93201 •93488 •93785 •94102 -94431 -94768 •95111 45 40 35 30 25 20 15 10 5 Temperatare, Alcohol Alcohol Alcohol Alcohol Alcohol Alcohol Alcohol Alcohol Alcohol Falif. 100 100 100 100 100 100 100 100 100 Water. Water. Water. Water. Water. Water. Water. Water. Water. Degrees. 30 0-96967 0^97200 0-97418 097635 097860 098108 0-98412 0^98804 099334 35 •96840 •97086 •97319 •97556 •97801 •98076 •98397 •98804 •99344 40 •96706 •96967 •97220 •97472 •97737 •98033 •98373 •98795 •99345 45 •96563 •96840 •97110 •97384 •97666 •97980 •98338 •98774 •99338 SO •96420 •96708 •96995 •97284 •97589 •97920 •99293 •98745 •99316 S5 •96272 •96575 •96877 •97181 •97500 •97847 •98239 •98702 •99284 60 •96122 •96437 •96752 •97074 •97410 •97771 •98176 •96654 •99244 j OS •95962 •96288 •96620 •96959 •97309 •97688 •98106 •98594 •99194 i 70 •95802 •96143 96484 •96836 •97203 •97596 •98028 •98527 •991341 75 •95638 •95987 96344 •96708 •97086 •97495 •97943 •98454 •99066' 80 -954671 958261 -961921 965681 •96963 •97385 •97845 -98367 -96991 j Experiments were made, by direction of the committee, to verify Gilpin's tables, which showed that the error introduced in ascertaining the strength of spirits by tables founded on Gilpin's numbers must be quite insensible in the practice of the revenue. The discrepancies thus detected, on a mixture of a given strength, did not amount in any one instance to unity in the fourth place of decimals. From a careful inspection of such documents the committee are of opinion, that Gilpin's tables possess a desree of accuracy fax surpassing what could be expected, and sufficiently perfect fur all practical or sden- tinc purposes. The foUowing table is given by Mr. Lubbock, for converting the apparent specific gravity, or indication, into true specific gravity. B O •*I m u a — Temperature. -h Indication. 30° 32° 370 420 47« 529 570 62° 67«» 72° 77° 80° •82 •83 ■84 •85 •86 •87 •88 •99 •90 •91 •92 •93 •94 •95 •96 •97 •98 •09 i'lOO •00083 •00084 •00085 •00086 ■00087 •00088 •00089 •00090 •00091 •00092 •00093 •00094 00095 O0096 ■00097 •00098 •00099 •00100 •00101 •00078 ■00079 •00060 •00081 •00082 •00083 •00064 •00085 ■00085 •00086 ■00087 •00088 ■00089 ■00090 ■00091 ■00092 ■00093 •00094 •00095 •00065 -00066 -00066 •00067 00068 00069 •00070 -00070 •00071 •00072 ■00073 00073 •00074 -00075 00076 •00077 -00077 •00078 •00079 •00052 00052 00053 •00054 •00054 ■00055 •00055 ■00055 ■00056 -00057 •00058 •00059 •00059 -00060 •00000 •00061 •00062 ■00062 •00063 ■00039 ■00039 ■00039 •00040 00040 •00041 •00041 •00042 •00042 00043 •00043 ■00044 ■00044 •00045 •00045 •00046 •00046 •00047 •00047 •00025 •000-26 •00026 •00026 •000-27 •00027 •00027 •00028 •00028 •00028 00029 •00029 •00029 •00029 •00030 •00«30 •00030 •00031 •00031 •00012 •00012 00013 •00013 •00013 •00013 ■00013 •00013 •O0OI4 ■00014 00014 •00014 ■00014 •00014 •00014 •00015 •00015 00015 •00015 ■00011 •00012 ■00012 ■00012 •00012 -00012 -00012 00012 ■00013 -00013 00013 -00013 •00013 •00013 •00013 •00014 •00014 •00014 •00024 •00024 00024 •00025 •00025 •000-25 •00026 00026 00026 •00020 •00027 •00027 ■000-27 ■00028 ■00028 ■00028 00028 •00029 00035 00036 00036 •00037 ■00037 00037 00038 -00038 •00039 •00039 •00040 00040 ■00040 ■00041 •00041 •00042 ■00042 •00043 •00042 00042 00043 •00043 ■00044 00044 00045 •00045 00046 ■00046 00047 •00047 •00048 00048 ()0049 ■00049 00050 ■00050 •89 •83 •84 85 •8e 87 •68 «9 90 •91 •92 -93 •94 •95 •96 •97 •96 •99 100 ALCOHOL. 25 I i Fig, 5, 6 The hydrometer constructed, under the directions of the Commissioners of Excise, by A n^* **** * ^^^^ °^ ^ inches in length divided into 100 parts, and 9 weights. It has thus a lange of 900 divisions, and expresses specific gravities at the temperature of 62° Fahr. In order to render this mstrument so accurate a measurer of the specific gravity, at the standard tempei:ature, as to involve no error of an appreciable amount, Mr. Bate has constructed the weights (which in this instrument are im- mersed m the fluid of difl'erent specific gravities) so that each succes- sive weight should have an increase of bulk over the preceding weight equal to that part of the stem occupied by the scale, and an increase of weight sufficient to take the whole of the scale, and no more, down to the liquid. This arrangement requires great accuracy of workman- ship, and enhances the price of the instrument. But it allows of in- creased strength in the ball, where it is very much required, and it gives, upon inspection only, the indication (apparent specific gravity) by which the general table is to be examined and the result ascertained. J ig. 5 represents this instrument and two of its nine ballast weights. It comprehends all specific gravities between 820 and 1000. It indi- ItV ^'elSVi"" ^T"y "^'^^ ^^°^^ P^^^<^^ accuracy at the temper- ature of ^ Fahr. ; but it does not exclude other instruments from being used in conjunction with tables. The latter are, in fact, inde- pendent of the instrument, and may be used with gravimeters, or any instrument afibrding indications by specific gravity at a civen temperature. See Spiarrs. ° The commercial value of spirituous liquors being much lower in !• ranee than m England, a less sensible instrument becomes sufficient l^wi I'^J!"^^?^ ^^*' country. Baume's and Cartiers hydrometers, with short arbitrary scales, are very much employed, but they have been lately suner- seded by an ingenious and ready instrument contrived by M. Gay Lussac and cE by him an alcoometre He takes for the term of comparLon pure alcohol by volume at the temperature of 15° Cent., and represents the strength of 1^^100 c^/r« or by unity Consequently, the strength of a spirituous liquid is the n umber Tf Ten nmes in volume of pure alcohol which that liquid contains at the tempemmre of Is' tem~: onTcei/' '"C l"'' ^ Ti"^" hydrometer, and is gr'aduat Ji for ic lemperature ol 15 Cent. Its scale is divided into 100 parts or degrees each of which denotes a centmie of alcohol; the division at the bottom of the s m coi^eslnds o pure water, and the division 100 at its top, to pure alcohol When Tmme7sed iS a ^«rr'r •'*"°'^ *' ^^° ^^"i- (^^ ^^^'-^ ''' announces its strength Z^cUv For U rd^at^ef thatC^t^e^^^^^^ temperature of 15° Cent, it sinkf to thTdfvis'ion 5o' of Dure afoohol Tn ^ of this hquor is 50 per cent., or that it contains 50 centimes ?7 wt 1 V ^^ ''"f new British proof spirit, it would sink to nearly 57 indicat^^ 57 by volume of pure alcohol, allowing for condensation, or 60 by weY^Jht TtabL^f iTquors »" Th7TJZ T'rT' "5't '^ ^""^ " ^^^'« of rea/streS oflpTrhuous i^cl'nt Ih t? « ^.1'''^^ ''^^T!'. °^ ^^'^ ^^^^^ *=°ntains the temperatures, from 0» to Lhl. li';. ^^•'^ ^''•"'^^?^^^ ^'""^ ^^^ indications of the alcoLetre. InXs^ne table we have most ingeniously inserted a correction for the volume of the snfrk^ wW t Tr^::::re'TJ'7 r ^r- ''.^^ ^^^^ '''' mref oTgalt, SLIi'lt reals3thri5oL^/r ,KP'"*"'''i' ^'^"°i "^^^^^ ^PP"^"t strength is 44o ; its KlVlSot' ^"^SL'nlr -^"^ orVlonsf whicri[ r^ured 'S ^le^l^'''^^. r^h ^L I ; ^ number is inscribed in smaller characters in the same souare cell w.„ld have, when mfasired a, «.e i^m^nl^'^t^i^ i'[Z:fj X:^";: S' m9l^To-l9l!97T4u'^''""^ " "" temperature of 2°, will be. therefore.- .iiMy'nSJ? "'"''"^ '^"''"'' *"' «*''"»»«'. « e«M richm,, of ,pirU in alcolud, or IS^Cent '^?.„°'„"„tT''lf ^"'l^^?- *^ P'-^-'««»?. >>« «' " higher temperature than vojume win be 993 litres; it is inscribed directly below 49c-3, the real strength. We I I mm mm mmm- ae ALCOHOL. diall therefore have of pure alcohol, contained in the 1000 litres of spirits, measuied at the temperature of 25^ or their richness, 993 lit. X 0-493 = 489 lit. 55. "^^""^ *' ALCOHOL. Alcometrical Table of real Strength, by M. Gay Lussac (con/tntted). ar lii Alcometrical Table of real Strength, by M. Gay Lussac. - Temperature C. • 31c 32c 33c 34c 35e 36c 37c 38c 39c 40c Deg. 10 11 12 33 1002 34 1002 35 1003 36 1003 37 1003 38 1003 39 1003 40 1003 41 1003 42 1003 32-6 1002 33-6 1002 34-6 1002 35-6 1002 36-6 1002 37-6 1002 38-6 1002 39-6 1003 40-6 1003 41 6 1003 32-2 1001 33-2 1001 34-2 1002 33-8 1001 35-2 1002 36-2 1002 37-2 1002 38-2 1002 39-2 1002 40-2 1002 41 -2 1002 40-8 1001 IS 31-8 1001 32-8 1001 34-8 1001 * 35-8 1001 36 S 1001 37-8 1001 38-8 1001 39-8 100! 14 31-4 1001 32-4 1001 33-4 1001 33 1000 34-4 1001 34 1000 3oA 1001 36-4 1001 37-4 1001 38-4 1001 39-4 1001 39 1000 40-4 1001 16 16 17 18 19 20 31 1000 32 1000 35 1000 36 1000 37 1000 38 1000 46 1000 39-5 999 30-6 1000 30-2 999 31-6 1000 32-5 999 33-5 999 34-5 999 35-5 999 36-5 999 37-5 999 38-5 999 31-2 999 32 1 999 33 1 999 34 1 999 351 999 36 1 999 371 999 381 999 39-1 999 29-8 999 30-8 999 31-7 998 32-7 998 33-7 998 34-7 998 35-7 998 36-7 998 37-7 998 38-7 998 29-4 998 30-4 998 31-3 998 30-9 997 32-3 998 33-3 998 34-3 998 35-3 998 36-3 998 37-3 997 38-3 997 29 998 30 998 31-9 997 32-9 997 33-9 997 34-9 997 35-9 997 36-9 997 37-9 997 21 28-6 997 29-6 997 30-6 997 31-5 997 32-5 997 33-5 997 34-5 997 996 36-5 996 37-5 996 22 23 24 25 28-2 997 29-2 997 30 1 996 31 1 996 32-1 996 33 1 996 341 996 351 996 36 1 996 37 1 996 27-8 996 28-8 996 29-7 996 30-7 996 31-7 996 32-7 996 33-7 996 34-7 095 35-7 995 36-7 995 27-4 996 28-4 996 28 995 29-3 995 30-3 995 31-3 995 32-3 995 33 3 995 34-3 995 35-3 995 36-3 994 27 995 28 -9 29 -9 995 995 30-9 095 31-9 994 32-9 994 33-9 994 34 9 994 35-9 994 Teniperature. C. 41c 42c 43c 44r 45c 46c 47c 48c 49c 50c 11 12 13 14 43 1003 44 1004 45 1004 46 1001 46-9 1004 47-9 1004 48-9 1004 49-9 1004 50-9 1004 51-8 1004 42-6 1003 43-6 1003 44-6 1003 45-6 1003 46-6 1003 47-6 1003 48-6 1003 49-5 1003 50-5 1003 51-5 1003 42-2 1002 43-2 44-2 1003 45-2 1002 46-2 1003 47-2 1003 48-2 1002 49-2 1002 60-2 1002 51-1 1003 41-8 1001 42-8 1001 42-4 1001 43-8 1001 44 -S 1002 45-8 1002 46-8 1002 47-8 1002 48-8 1002 49 -S 1002 60-8 1002 41-4 1001 43-4 1001 44-4 1001 45-4 1001 46-4 1000 47-4 1001 48-4 1001 49-4 1001 50-4 1000 50 1000 15 41 1000 42 1000 43 1000 44 1000 45 1000 46 1000 47 1000 48 1000 49 1000 16 40-6 999 41-6 999 » 42-6 999 43-6 999 44-6 999 45-6 999 4G'6 999 1 47-6 099 48-6 099 49-6 999 I Teniperatare C. • 41c 4ac 43c 44r. 45c 46c 47c 48c 49c 50c Deg. 17 18 19 so SI 82 S3 24 25 40-2 999 41-2 999 42-2 999 43-2 998 44-9 998 45-2 998 ' 46-2 47 -2 998 998 48-2 998 49-2 998 39-8 098 40-8 998 41-8 998 42-8 998 43-8 998 44-9 998 45 -9 46 -9 998 998 47-9 998 48-9 998 39-4 997 40 4 997 41-4 997 42-5 997 43-5 997 44-5 997 45 -S 99^ • 46-5 997 1 47-5 997 48-5 997 39 997 40 997 41 997 40-6 996 42 1 997 43 1 996 441 996 451 996 46 1 996 47-2 996 48-2 996 38-6 990 39-6 99G 41 -7 996 42-7 996 43-7 996 44-8 996 45-8 996 46-8 995 47-8 995 38-2 996 39-2 095 40-2 995 41-3 995 42-3 995 43-3 995 44-3 995 45 3 995 46-4 995 47-4 995 37-8 995 38-8 995 39-8 995 40-9 994 41 -9 994 42-9 994 43-9 994 44-9 994 46 994 47 994 37-4 994 38-4 994 39-4 994 40-5 994 41-5 994 42-5 994 43-6 994 44-6 994 45-6 993 46-6 993 37 38 994 994 39 1 993 401 42-1 993 993 42-2 993 43-2 993 44-2 9i*j 45-2 993 >6-3 993 Tempera lure. C. 51c 52c. 53c 54c 55c 56c 57c 58c 59c 60-7 1004 60c Deg 10 11 12 13 14 15 16 17 18 19 52-8 1001 53-8 1004 54-8 1004 55-8 1004 56-8 1004 57-8 1004 58-8 1004 59-7 1004 61-7 1004 62-5 1003 53-5 1003 54-4 1003 55-4 1003 56-4 1003 57-4 1003 58-4 1003 59-4 1003 60-4 1003 61-4 1003 52 1 1003 53 1 1002 54-1 1002 55 1002 56 1002 57 1003 58 1002 59 1002 60 1002 61 1002 51.8 1002 52-7 1O02 53-7 1002 54-7 1002 65.7 1003 56-7 1002 57-7 1002 68-7 1003 59-7 1002 60-7 1002 51-4 1001 52-3 1001 53-3 1001 54-3 1001 55 3 1001 56-3 1001 57-3 1001 58-3 1001 59-3 1001 60-3 1001 51 1000 52 1000 53 1000 54 1000 55 1000 56 1000 57 1000 58 1000 59 1000 60 1000 50-6 999 51-6 999 52-6 999 53-6 999 54-6 999 55-6 999 56-6 999 57-6 999 58-6 999 59-6 999 50-3 998 51-3 998 52-3 998 53-3 998 54-3 998 55-3 998 56-3 998 55-9 998 57-3 998 58-3 998 59-3 998 49-9 998 50-9 998 51-9 998 52-9 998 53-9 998 54-9 998 56-9 997 57-9 997 58-9 997 49-5 997 50-6 997 51-6 997 52-6 997 63-6 997 54-6 997 55-6 997 56-6 997 57-6 997 58-6 997 20 49-2 996 50-2 996 51-2 996 52-2 996 53-2 996 54-2 996 55-2 996 54-9 995 56-2 996 57-2 996 58-2 996 21 48-8 995 49-8 995 60-8 995 51-8 995 52-9 995 53-9 995 55-9 995 56-9 995 57-9 995 22 48-4 995 49-4 995 50-4 995 51-4 994 62-5 994 53-5 994 54-5 994 55*5 994 56-5 994 57-5 994 23 48 994 49-1 994 50-1 994 51-1 994 52-1 994 53 1 994 54-1 994 551 993 56 1 993 57 1 993 S4 47-6 993 48-7 993 49-7 993 50-7 993 51-8 993 52-8 993 53-8 993 54-8 993 55-8 993 56-8 992 S5 47-3 48-3 993 49-3 993 50-3 992 51-4 992 52-4 992 53-4 992 54-4 993 5.'> 5 092 56-5 993 1 7 28 ALCOHOL. f Alcometrical Table of real Strength, by M. Gay Lussac (continu&T^ 1. Temperature C. 61c 62c 63c 64c 65c 66c 67c 68c 69c 70c Deg. 10 11 IS 13 14 1» 16 17 18 19 SO 21 22 23 24 25 62-7 1004 63-7 1004 64-7 1004 65-7 1004 66-7 1004 67-6 1004 68-6 1004 69-6 1004 70-6 1004 71-6 1004 62-4 1003 63-4 1003 64-4 1003 65-4 1003 66-4 1003 67-3 1003 68-3 1003 69-3 1004 70-3 1004 71-3 1004 62 1003 63 1003 64 1003 65 1003 66 1002 67 1002 68 1003 69 1003 70 1003 71 1003 61.7 1002 62-7 1003 63-7 1002 64-7 1002 65 7 1002 66-7 1002 67-7 1002 68-7 1002 69-6 1002 70-6 1002 61-3 1001 62-3 1001 63-3 1001 64-3 1001 65 3 1001 66 1000 66-3 1001 67-3 1001 68-3 1001 69-3 1001 70-3 1001 61 1000 62 1000 63 1000 64 1000 66 1000 67 1000 68 1000 69 1000 70 1000 60-6 999 61-7 999 62-7 999 63-7 999 64-7 999 65-7 999 66-7 999 67-7 999 68-7 999 69-7 999 60-3 998 61-3 998 62-3 998 63-3 998 64-3 998 65-3 998 66-3 998 67-3 998 68-3 998 69-3 998 59-9 997 61 997 62 997 63 997 64 997 65 997 66 997 67 997 68 997 69 997 59-6 997 60-6 997 61-6 997 62-7 997 63-7 997 64-7 997 65-7 997 66-7 997 67-7 990 68-7 £96 59-2 996 60-3 996 61-3 996 62-3 996 63-3 996 64-3 996 65-4 996 66-4 996 67-4 996 68-4 996 58-9 995 59-9 995 61 995 62 995 63 995 64 995 65 995 66 995 67 995 681 995 58-5 994 59-5 994 60-6 994 61-6 994 62-7 994 63-7 994 64-7 994 65-7 994 66-7 994 67-8 994 58-1 993 59-2 993 60-2 993 61 -3 993 62-3 993 63-3 993 64-3 993 65-4 993 66-4 993 67-4 993 57-8 992 58-9 992 69-9 992 61 992 62 992 63 992 64 992 65 992 66 992 67-1 992 57-5 992 58-5 992 59-5 «192 60-6 99) 61-6 991 62-6 9QI 63-7 991 64-7 991 65-7 991 66-7 991 'Temperature. C. 71c 72c 73e 74c 75c 76c 77-5 1005 77c 78c 79c 80c 11 IS 13 14 72-6 1004 73-5 1004 74-5 1005 75-5 1005 76-5 1005 78-5 1005 79-5 1005 80-5 1005 81-5 1005 72 3 1004 73-2 1004 74-2 1004 75-2 1004 76-2 1004 77-2 1004 78-2 1004 79-2 1004 SO -2 1004 81-2 1004 72 1003 72-9 1003 73-9 1003 74-9 1003 75-9 1003 76-9 1003 77-9 1003 78-9 1003 79-9 1003 80-9 1003 71-6 1002 72-6 1002 73-6 1002 74-6 1003 75-6 1002 76-6 1002 77-6 1002 78-6 1002 79-6 1002 80-6 1002 71-3 1001 72-3 1001 73-3 1001 74-3 1001 75-3 1001 76-3 1001 77-3 78-3 1001 1001 79 '3 1001 80-3 100^ 15 71 1000 72 1000 73 1000 74 1000 75 1000 76 1000 77 1000 78 1000 79 1000 80 1000 16 70-7 999 71-7 999 72-7 999 73-7 S99 74-7 999 75-7 999 76-7 999 77-7 999 78-7 999 79-7 999 17 70-3 998 71-3 998 72-3 998 73-3 998 74-3 996 75-4 998 1 76-4 998 77-4 998 78-4 998 794 908 ALCOHOL. Alcometrical Table of real Strength, by M. Gay Lnssac (amtinued). 29 Tssperatore C. 71c 72c 73c 74c 75c 76c 77c 78c 79c 80c 19 90 91 S2 S3 24 25 70 997 71 997 72 997 73 997 74 997 75 1 997 76 1 997 771 997 78-1 997 79-1 997 69-7 996 70-7 996 71-7 996 72-7 996 73-7 996 74-7 996 75-8 996 76-8 996 77-8 996 78-8 996 69-4 996 70-4 996 71-4 995 72-4 995 73-4 995 74-4 995 75-5 995 76-5 995 77-5 995 78-5 995 691 995 70-1 995 71 1 995 72 1 994 73 1 994 74 1 994 75-2 994 76-2 994 77-2 994 78^ 994 68-8 994 69-8 994 70-8 994 71-8 994 72-8 993 73-8 993 74-8 993 75-9 993 76-9 993 77-9 993 68-4 993 69-4 993 70-5 993 71-5 993 72-5 992 73-5 992 74-5 992 75-5 993 76-6 992 77-6 1 992 68-1 992 67-8 991 69-1 992 70-1 992 71-2 992 72-2 992 73-2 992 74-2 992 75-2 991 76-3 991 77-3 991 68-8 991 69-8 991 70-8 991 71 -8 991 72-8 991 73-9 991 74-9 991 76 991 77 991 Temperature. C. 81c 82c 83c 84c 85c 86-4 1005 86c 87c 88c 89c 90e Deg. 10 11 12 13 14 15 16 17 18 19 20 21 22 23 34 82-4 1005 83-4 1005 84-4 1005 85-4 1005 87-4 1005 88-3 1005 89-3 1005 90-2 1005 91-2 1005 82-2 1004 83 1 1004 84-1 1004 85-1 1004 861 1004 87-1 1004 86-8 1003 88 1004 89 1004 90 1004 91 1004 81-9 1003 82-9 1003 83-9 1003 84-8 1003 85-8 1003 87-8 1003 88-7 1003 89-7 1003 90-7 1003 81.6 1002 82-6 1002 83-6 1002 84-6 1003 85 -5 1002 86-5 1002 87-5 1003 88-5 1003 89-5 1002 90-5 lOOS 81-3 1001 82-3 1001 83-3 1001 84-3 1001 85-3 1001 86-3 1001 87-3 1001 88-2 1001 89-2 1001 90-2 1001 81 1000 82 1000 83 1000 84 1000 85 1000 86 1000 87 1000 88 1000 89 1000 90 1000 80-7 999 81-7 999 82-7 999 83-7 999 84-7 999 85-7 999 86-7 999 87-7 999 88-7 999 89-7 999 80-4 998 81-4 998 82-4 998 83-4 998 84-4 998 85-4 998 86-4 996 87-4 998 88-4 998 89-5 998 801 997 81-1 997 82 1 997 83-1 997 84-1 997 85-2 997 86-2 997 87-2 997 88-2 997 89-2 997 79-8 996 80-8 996 81-9 996 82-9 996 83-9 996 84-9 996 85-9 996 86-9 996 87 -9 996 88-9 996 79-5 995 80-5 995 81-6 995 82-6 995 83-6 995 84-6 995 85-6 995 86-6 995 87-7 995 88-7 995 79-2 994 80-2 994 81-3 994 82-3 994 82 993 83-3 994 84-3 994 86-3 994 86-4 994 87-4 994 88-4 994 78-9 993 79-9 993 81 093 S3 993 84 093 85 993 861 993 87 1 993 88-2 993 78-6 992 79-6 992 80-7 992 81-7 992 82-7 992 83-8 992 84-8 993 85-8 992 86-8 998 87-9 993 78-3 991 79-3 991 80-4 991 81-4 991 82-4 991 83-5 991 84-5 991 85-5 991 86-5 991 87-6 991 95 78 091 79 991 80-1 990 81-1 990 821 990 83-2 990 i 84-2 990 85-2 990 86-3 990 87-4 000 30 ALCOHOL. I consider the preceding table, which I have extracted from the longer tables of M. Gajr Liissac, as an important addition to the resources of British dealers and manu- facturmg chemists. With the aid of his little instrument, which may be got for a trifle from its ingenious maker, M. Collardeau, Rue Fauburg St. Martm at Paris, or constructed by one of the London hydrometer artists, the per centage of real alcohol, and the real value of any spirituous liquor, may be determined to sufficient nicety for most purposes, in a far easier manner than by any instruments now used in this coun- try. It has been adopted by the Swedish government, with M. Gay Lussac's tables. M. Gay Lussac's table gives, by inspection, the true bulk of the spii-its as corrected for temperature ; that is their volume, if of the normal temperature of 15** Cent. {o9<* Fahr). Now this is important infoi-mation ; for, if a person buys 1000 gallons of spirits in hot weather, and pays for them exactly according to their strength corrected for temp^ature, he will not have 1000 gallons when the weather is in its mean state. He may lose, in this way, several gallons, without being aware of it from his hydrometer. Sometimes, after moist autumns, when damaged grain abounds, the alcohol distilled from its fermented wash contains a peculiar volatile body. "When we apply our nose to this species of spirits in its hot state, the volatile substance dissolved in it irritates the eyes and nostrils ; it has yerj nearly the same smell as an alcoholic solution of cyanogen, as any chemist may discover by standing near the discharge pipe of the refrigeratory worm of a raw-grain whisky still. Such spirits intoxicate more strongly than pure spirits of the same strength, and excite, in many persons, even temporary frenzy. It is a volatile fatty matter, of a very fetid odor, when obtained by itself, as I have procured it in cold weather at some of the great distilleries in Scotland. It does not combine with bases. At the end of a few months, it spontaneously decomposes in the spirits and leaves them in a less nauseous and noxious state. By largely dilut- ing the spirits with water, and distilling at a moderate temperature, the greater part of this oil may be separated. Part of it comes over with the strongest alcohol, and part with the latter runnings, which are called by the distillers strong and weak feint*. The intermediate portion is purer spirit The feints are always more or less opalescent, or become so on dilution with water, and then throw up an oily pellicle upon their surface. The charcoals of light wood, such as pine or willow, well calcined, and in- fused in sufficient quantity with the spirits prior to rectification, will deprive them of the greater part of that oily contamination. Animal charcoal, well calcined, has also been found useful ; but it must be macerated for some time with the empyreumatic spirits, before distillation. Another mode of separating that offensive oil is, to agitate the impure spirits with a quantity of a fat oil, such as olive oil, or oil of almonds, to decant off the oil, and re-distil the spirits with a little water. Digestion and agitation with calcined magnesia, for some time, followed by filtration and distillation, are also good means of improving the flavor of alcohol The taste of the oil of grains is best recognized by agitation with water, whereby, on standing, the diluted spirit throws up a film of oil, risible by reflected light If the spirit be mixed with a few drops of nitrate of silver and exposed for some time to sunshine, the oil will react upon the oxide of silver, and cause a brown tinge ; but if there be no oil present, the spirits will remain limpid. If one part of hydrate of potash, dissolved in a little water, be mixed with 160 parts of spirits, and if the mixture be well shaken, then slowly evaporated down to 15 parts and mixed with 15 parts of dilute sulphuric acid in a phial, to be then corked, there will soon exhale from the mixture a peculiar offensive odor, characteristic of the quality and origin of the impure spirit, whether obtained from raw grain, from malt, from potatoes, rye, arrack, rum, brandy, : his Elements of Chemistry. Having, in the long interval since, contrived many modifications of the instrument, and having extended its principle to testing other articles I am induced to offer it now to the world, in consequence of the recent appearance of a publication upon the same subject, by two very ingenious chemists of Liebig's school, Drs. R. Fresenius and H. Will. Of their system of alkalimetry, &c., a copious abstract appeared in the Annahn der Chimie und Pharmacie for July last, and about the same time a pamphlet was published by Winter, at Heidelberg, under the title Neue Verfahrungsweisen zur Bestimmung des Werthes der Pottasche und Soda, der Sauren, und des Braunstein; or "New Processes for determining the Value of Potash and Soda, of Acids, and Black Oxide of Manganese." However accurate these processes may be, and however apt for a German or French student of chemistry, they are, in my apprehension, not at all fitted for the famihar use of manufacturers and dealers in any country, and certainly not for those of the United Kingdom. Descroizilles was the first person who contrived an instrument, called an alkalim- eter, to ascertain the alkaline strength of potash and soda, without much calcula- tion. His method was described in the Annales de Chimie for 1806, tom. Ix.. and a translation of it appeared in our Philosophical Magazine, vol. xxviii., for Jaly ul !t^°^^ f*^®" u? "'"■**® °^ potash, nitrate of soda,«nd to white lead, either in powder or in paint. My nitrometer enables a person not at all versant in chemistry to ascertain in a quarter of an hour. T^l Lln?^ .*"* processes, the quantity of pure nitrate in either of these salts, to one part in 200. The cerussa-metei is equally simple and expeditious, r "* *"v. u ALKALIMETRY. ALKALIMETRY. 86 I and August of the following year. His apparatus consisted of a glass tube, 8 or 9 inches long, and 7 or 8 lines in diameter, closed at one end, but terminated at the other in a kind of small funnel (with a beak or spout), connected to the tube by a narrow neck, having a calibre of two lines and a half. Upon the shoulder, under the throat, there was a hole for admitting air to the long tube in the act of being emptied, by sloping its mouth downward. This cylindrical vessel was to contain 38 grammes of water, which space was divided into 76 equal parts, which it was extremely important to proportion accurately. The liquor was prepared by taking concentrated sulphuric acid, at 66^ Baumc (1'845 spec, grav.), and diluting it with nine times its weight of water. The instrument being poised in a balance, he introduced into it very exactly two grammes of the above test acid, and when the instrument stood upright, he scratched a line at the level of the liquor, and thus proceeded by addition of successive grammes to graduate the whole, till 36 were added, after which he subdivided these spaces by lines into 72 demi-gramme volumes. He then proceeds to describe eight different subsidiary articles required for hb oper- ations : — " Mkalimetrical trials of potash. — Weigh exactly one demi-gramme of potash, put it into a glass, and pour upon it about four fifths of a decilitre of water ; facilitate the solution of the potash by stirring it with a small chip of wood, three or four times in an hour and a half, a minutfe at each time. When the solution is effected, pour it into the small tin measure, No. 4, which is to be then filled up with water ; pour it back again into the glass, in which you must still pour a measure full of pure water; stir this new mixture also three or four times within half an hour, in order to facilitate the precipitation of a slight sediment, which soon falls down. This sediment being completely formed, slope the glass with caution, in order to fill with clear liquor the small measure ; then empty this last into another large glass ; after this place round the edges of a plate drops of syrup of violets; pour also into the alkalimeter test liquor until the line marks ; take it afterward with the left hand, inclining it upon the glass which con- tains the moiety of the clean alkaline solution : the acid liquor will fall into it by hasty drops, or in a very small thread, which you may moderate at pleasure, by retarding the entrance of the air at the lateral hole or vent, upon which must be placed the end of the finger ; at the same time, with a small stick or match, assist the cixture and fa- cilitate the development of the carbonic acid which is manifested by effervescence. When you have emptied the alkalimeter to about the line 40, try if the saturation approaches, by drawing your small stick from the mixture, and resting it upon the drops of syrup of violets, which should become green, if the potash is not of a very inferior quality. If, on the contrary, the violet color is not altered, or what would be worse, if it be changed into red, there would be, in the first case, an indication of saturation, and in the second a proof of super-saturation. But this is not the case with good potashes ; at that line, the liquor tried can alter the syrup of violets into green only ; or cause to return to the violet, and even to the green, the drops which had been changed into red at the time of a former trial ; we must, therefore, in general add more acid, which occasions a new effervescence. This addition must always be made with caution, and we must touch every time a drop of syrup of violets in order to stop. When at last the latter assumes a red hue, then, after having restored the alkalimeter to a perpendicular position, in order to see at what line the testing liquor stops, yon must reckon one degree less, in order to compensate the excess of saturation. The mean term of potashes is 56; this implies that they require for their saturation ^/y-;^ re hundredths of their weight of sulphuric acid." For the analysis of commercial sodas of all kinds, M. Descroizilles prescribes using ten and a half deci-grammes of this alkali, instead of the ten deci-grammes for potashes, and proceeds as above detailed. In his table of results annexed, we find American potashes called 60° to 63°. American pearlashes Dantzic potash Alicant soda bCP to55«» 4d to 55 20 to 33 It is obvious, from these statements, that the alkalimeter so made and graduated denoted comparative, but not absolute, quantities of alkalis present in the com- mercial samples. The rest of his very long memoir is occupied with what he calls the graduation of potashes and sodas, the economy of their graduation, the proportions of carbonic acid in them, the processes of caustification, the presence of potash in all lime which is burnt by a wood fire, origin of neutral soda, and probable origin of oatrum; without any more explicit instructions. The instrument, as left in this vague state, never was employed, nor could it come into use, among English manufBcturers and dealers. The next alkalimeter, of which an account has been published, was my own. In con- structing this instrument, I availed myself of the lights recently shed on chemical pro- portions by Dr. Dalton's atomic theory, and I thus made it to represent, not relative, but absolute measures of the amount of real alkali existing in any commercial sample. The test-liquor used at that time was sulphuric acid, which is most readily and accurately diluted to the requisite degree by means of a glass bead, very carefully made, of the specific gravity that the standard acid should have. In order to make the test-liquor, therefore, nothing more is requisite than to put the bead into distilled water, and to add to it somewhat dilute but pure sulphuric acid, slowly and with agitation, till the bead rises from the bottom, and floats in the middle of the liquor at the temperature of 60^ Fahr. The delicacy of this means of adjustment is so great, that a single degree of increase of heat will cause the bead to sink to the bottom — a precision which no hydrom- eter can rival. The test-tube, about 14 inches long, contains generally 1,000 grains of water, and is graduated into 100 equal parts by means of equal measures of mercury. The test-liquor is faintly tinged with red cabbage or litmus ; so that the change of color, as it approaches to the saturating pitch, on adding it to 100 grains of the com- mercial alkali, becomes a sure guide in conducting the experiment to a succep^ful issue. One hundred measures of this test-liquor neutralize exactly 100 grains of absolute soda (oxide of sodium), and of course very nearly 150 of potash. A bead may also be ad- justed for test-liquors, of which 1,000 grain measures neutralize 100 of potash, and therefore 66f of soda, as well as other proportions, for special purposes of greater minuteness of research. One may be so graduated as to indicate clearly a difference of L_ of a grain of ammonia. In making such nice experiments, it is of course requisite to free the alkaline matter beforehand from sulphurets, sulphites, and hyposulphites, by igniting it in contact with chlorate of potash, as long since recommended by Gay- Lussac. With such means in careful hands, all the problems of alkalimetry may be accurately solved by an ordinary operator. On the same principle, my Acidimeler is constructed ; pure water of ammonia is made of such a standard strength by an adjusted glass bead, as that 1,000 grain meas- ures of it neutralize exactly a quantity of any one real acid, denoted by its atomic weight, upon either the hydrogen or oxygen scale or radix ; as for example, 40 grains of sulphuric acid. Hence it becomes a universal acidimeter; after the neutralization of 10 or 100 grains of any acid, as denoted by the well-defined color in the litmus- tinted ammonia, the test-tube measures of ammonia expended being multiplied by the atomic weight of the acid, the product denotes the quantity of it present in 10 or 100 grains. The proportion of any one free acid in any substance may thus be deter- mined with precision, or to one fiftieth of a grain, in the course of five minutes. Like methods are applied to Chlorometry, and other analytical purposes, with equal facility ; adapting the test-liquor to the particular object in view. Instead of using beads for preparing the alkalimetric and acidimetric test-liquors, specific gravity bottles, or hy- drometers, may of course be employed ; but they furnish incomparably more tedious, and less delicate means of adjustment. To adapt the above methods to the French weights and measures, now used generally also by the German chemists, we need only substitute 100 deci-grammes for 100 grains, and proceed in the graduation, &c., as already described. The possession of two reciprocal test-liquids affords ready and rigid means of verifi- cation. For microscopic analyses of alkaline and acid matter, a graduated tube of small bore, mounted in a frame with a valve apparatus at top, so as to let fall drops of any size, and at any interval, is desirable; and such I have employed for many years. Of this kind is my ammonia-meter, u^ed in the ultimate analysis of guanos and other azotized products, in conjunction with a modified apparatus on the principle of that of Varrentrapp and Will. It may be remarked, that when the crude alkali contains some hyposulphite, it should not be calcined with chlorate of potash, because one atom of hyposulphurous acid is thereby converted into two atoms of sulphuric, which of course saturate double the quantity of alkali, previously in combination with the hyposulphurous acid. In such cases it is preferable to change the condition of the sulphure'ts, sulphites, and hyposulphites, by adding a little neutral chromate of potash to the alkaline solution, whence result sulphate of chromium, water, and sulphur, three bodies, which will not affect the accuracy of the above alkalimetrical l)roce8s. In the .Annals of Philosophy for October, 1817, I described a new instrument for analyzing the earthy and alkaline carbonates, and for determining the quantity of base present in them from the volume of carbonic acid, disengaged by their solution in acids, upon the data of the atomic theory. This method was applied to the analysis of the carbonates of ammonia, soda, potash, lime, magnesian limestone (dolomite), &c. " The indications of the above analytical instrument are so minute as to enable va, by the help of the old and well-known theorem for computing the proportions of two I 36 ALKALIMETRY. •^e^W n^on^^-"^^ ^'^""i^l ^^^"^ *"«y t° ^«^"<^e the proportions of the bases from .he volume of gas disengaged by a given weight of a mix^ carbonate."' at thP oSt instrument consisted of a bent glass tube, open at one end, and terminated ?eauh-Pd Sr '*^•^'' egg-shaped bulb from two to three inches in diameterTnd it Inn«l t ^^'ff^P^'^Vng ^>th it, about five pounds of quicksilver. The foUowiireW apparatus (Jig. 6) wiU be found more generally convenient, and equally exTctf Tis a cylinder, 2 inches in diameter, and 14 inches long, it con- tains 10,000grainsofwater in the graduated portion; 0, or zero being at the top. It has a tubulure in the side close to the bottom, through the cork of which a short tube passes tight, and IS connected to a collar of caoutchouc, e, which serves for a joint to the upright tube, B, resting near its open upper end in a hooked wire. Through the cork in the mouth of the cylinder, in!n?t w1!^ ""^A^^- ^^'^ "" P^''^' air-tight. The small tube f open at both ends, is cemented at bottom into the taU of c, and and Uni-^^ '^-^"i^f ""[ '^' ^'''^' "^^^ '"^'^ ^^ ^ « perfo/ated, t^th ff 'l^'*'"'' ''^^ ^^^ taper tube r, which can also be closed with the stopcock. In operating with this apparatus, proceed as follows :— J? Ill the cylinder with water, and cover its surface with half an inch of oil. Insert the tail of the flask. Put into the flask c, 58 6 grains of carbonate of potash, or 45-2 of carbonate of soda according as common pearl-ash or soda-ash is to be tested, alone with as much water as wiU cover fully the lower end of d, and n/.? ^^^'^^^."^^e this tube. Have a bottle containing aboit 40 Z p/ T L r'il"''^? previously mixed with 60 of water, and cooled. 1 ake of this, m a pouring or dropping glass, 100 water gram measures, and suck this quantity graduaUy up into the tube y, then shut the stopcock. On opening it slightly the acid wiU tail into c, and as slowly as may be prudent. The carbonic acid gas, forthwith disengaged, will depress the water in a, cause an overflow of it from the tube b, which, being held in the left hand, must have its swanbeak placed over a basin, and progressively lS^''^^^.^^^ ^r^^ °^^^" descending water in the cylinder! VVben all the sulphuric acid has been introduced by the right hand, the onfice of d is to be corked, and the tube b continually lowered with the left, tiU the effervescence being finished, the water m a remains stationary. The number on the centi^ade ures for the bulk of AlhZ.l'-^^^^A'i^ !? ^^^ '"^^^'^ ""^ ^^^ °"' deducting 100 grain meas- LTorofsoda " tfp «^^^^^^ •''''*^' ^^^ per-centage of pure carbonate of pot- f^n nJu *' u ^^^^^^ ""^^^ examination. The above prescribed wei-hts of these Hma" SclSTo'^^^^^^^ ^^^^"^^^=^^ ^^^^ ^y '^' -^tion of 's ulphurk S (us^^^ i^thf scale on i'ThP^'n^r f ^^V^Pl^^^^^s of carbonic acid gas, or lOO^ieasures measures o tha^thpwt ^^'^^fi[ ^^^ ^°"*^'"« ^^«"t 12,000 water grain S-theTwer tubulure tZ f ^^^f^t.^^ade scale is fully two inches above the level cenvLierin cPrt«?n V.e^ capacity and the graduation into 120 parts, will be found Wrrav PstTmaTp imSn^ /' '^^ '" analyzing bicarbonates of potash and soda.f weigh 1^ 4 gri ns nni t^^T?"^*" ^-'^ measures of carbonic acid at 6(P Fahr., to we f DD ied thP rr;,w ! *-^"' ^T^'''^ ^^^^ ^ magnified scale we should possess if r. «« o 1? t^'V ^^^'^ contrivance here, as we do to barometers. At any rate he must the a W^::nsT^^^^^^^ -'^^ T '^^^""^^ ^^^ ^'^^"^ «^^^ alkalineCbonateTby me aoove means, to one part m a thousand. standarf'wei^htTr.iv°''i!'°''''' T'^''^ ^l'^ ^^-l grains should be taken as the out on soCfn frf H?i 7' ^'^"'-^ ^^^^ ^"«^* °^ P"^« carbonate of lime should give IT. 4nio inn f^""^^ muriatic acid 10,000 water grain measures of carbonic acid gas. Since 100 water grain measures of liquid hydrochloric acid, specific gravitvW4 r;"d rt'e'exo'^riment ^Th'" '''' above height' of carbonates%KamUy may be used in the experiment. The preceding instrument will be found more convenient in expenmenting, as also the system of indication, than one on similar priSes con^ Btructed by the ingenious Dr. Mohr, of Coblenz. pnuupies con- In examining bicarbonates of potash and of soda, the weights to be used in the above apparatus are 42 grams of the former, and 35i ^ins of the latter, each of whiS » Dictionary of Chemistry, 1821, t For the greatest precision hot acid may he used in the above exnerimpnt hv fairi-»,«. i« . a . j ALKALIMETRY. 87 quantities, if the salts b« perfect, will disengage 10,000 water gram measures of car- bonic acid gas, by the action of sulphuric acid. There will be no harm in taking the formerly prescribed measure of the sulphuric acid though considerably less would answer the purpose. The centigrade measures of gas obtained in A will indicate the carbonated state of the two alkalis respectively. Their alkaline force may be most readily ascertained by my old alkalimeter, with colored test acid. Since the bicar- bonates usually sold in our shops, especially that of soda, are far from being exact atomic compounds, they should be always examined, both for their base and acid, which may also be well done in the following way, where the quantity of carbonic acid gas is determined by weight instead of by volume. For this purpose, a small compact apparatus of the annexed form (yig. 7) will be found convenient ; it is to be used in conjunction with my alkalimeter. a in the dotted line is the phial for receiving the carbonate to be tested, b, the funnel into which the test acid is to be poured ; c c, an inverted syphon filled with pieces of chloride of calcium for absorbing the aqueous vapors exhaled by the carbonic acid. The loss of weight in the phial above that in the tube of test acid shows the quantity of acid gas, and the indication of the alkalimeter tube, that of alkaline base, from which data the proportion of neutral carbonate and bicarbonate may be immediately deduced. Thus, 100 grains of bicarbonate of soda should give out 51| grains of carbonic acid, and saturate 37*6 cen- tigrade measures of the test acid, equivalent to 37*6 grains of real soda. But if neutral carbonate of soda be present, less gas will be given out, and more or less alkali may be indicated, according to the degree of dryness of the neutral soda. The amount of water in the bicarbonate may be de- termined by igniting 20 grains in a test tube, connected with the chlorcalcium inverted syphon ; 10 J grains of carbonic acid gas should be expelled, and 2J of water, making a total loss of 1211 grains, of which 2| will be found as water ab- sorbed by the chlorcalcium. But since a very moderate heat suflices to expel the second atom of carbonic acid from the bicarbonate of soda, the readiest mode of estimating its quality is to heat, over a spirit lamp, in a small flask, or retort, connected air-tight by a tube with the mouth of the cylinder a, {fig. 6) 70| grains of the supposed bicarbon- ate. Of the perfect salt this quantity should give out pretty exactly 10,000 grain measures of gas ; and whatever aliquot part of this volume is evolved will indicate, without calculation, the relative value of the substance as a bisalt. Thus if 8,500 grain measures of gas are obtained, 85 parts of bicarbonate of soda are present in 100. The crystalline form ofbicarbonate of potash is a tolerably good criterion of its quality. The quantity of caustic alkali mixed with carbonate may be readily determined, with sufficient accuracy, by the expert use of my alkalimeter ; because, till the caustic portion be nearly neutralized, little or no carbonic gas is expelled. When the effervescence at length begins, the test measures already expended denote the per- centage of caustic alkali. It is not right to disregard the alkali which is present in the slate of sulphuret, because as such it is effective in many processes of the chemical arts; in the manufacture of yellow soap, crown glass, in the bleaching of linen and cotton goods, &c. The alkalimeter, directly applied, will show the alkali present in this form, when compared with that indicated after ignition of the crude alkali with chlorate of potash, or after its treatment with yellow chromate of potash.* A few years ago I had the following apparatus made for the ready analysis of car- bonates, by ascertaining the loss of weight they suffered from the disengagement of their carbonic acid gas, during their solution in an acid, a, b {fig. 8) are two globes, of about two inches in diameter each ; a has its inferior neck strangled into a bore nearly capil- lary ; b stands lower, with its centre line on a level with the narrow neck of b. The tubes of these globes are about one half inch in diameter, c is shut at top with a per- forated cork, through which enters, air-tight, a small glass tube, which is bent across to the mouth of the tube e, and then passes down into it a little below the centre line of * If the alkaline carbonate contains sulphuret, sulphite, or hyposulphite, a teaspoonful of vellow chromate of potash may be added tc it, wherefrom result sulphate of chromium, water, and sulphur, which remainm the apparatus without effecting its weight. The mutual action of neutral chromate of potash and of sulphuret of potash, &c., has been discussed in an ingenious paper pubUshed by Doppin^ In the AnnaUH dtr Chtmte for May, 1843, p. 17«. r r r / rf "•* S8 ALKALIMETRY. ALKALIMETRY. M If! the globe b. This globe is rather more than half filled with sulphuric acid, when the instrument is employed in the analysis of the carbonates. The standard weight of car- bonate of soda = 24^ grains, or of carbonate of potasn = 31 J grains, is then put into a, having previously laid a minute globe of glass over the lower orifice ; the cork, with its small tube, is now firmly adjusted ; and the appa- ratus is weighed in its upright position, either by suspen- sion with a hook to the end of the beam, or by resting it on the scale in a light socket of any kind. It is next laid hold of, and inclined so as to cause a little of the acid in b to pass over into a. Effervescence ensues with greater or less vehemence, according to the nature of the carbonate and quantity of the acid introduced. Should it be too violent, and threaten an overflow by intumescence, it can be in- stantly abated to any degree by the slightest slope of the instrument. Now, this power of control forms the pe- culiar feature and advantage of this contrivance ; whereas in all other forms of such apparatus that I know, whether by sucking over or pouring in, if a little too much acid comes upon the carbonate, the experiment is effectually marred. The gas disengaged in a must necessarily tra- verse the sulphuric acid in b, and be stripped of ita moisture before escaping into the air. Having super- saturated the alkaline base, and cooled the apparatus, we weigh it again, and the loss of weight in grains and tenths denotes the per-centage of soda or potash, provided their neutral carbonates had been the subjects of experi- ment. For limestone, on the same plan of computation, 22| grains may be taken. It deserves to be noted, that the •M««j^ r 1 • 1- . present instrument has only one junction, and needs no wntain it •"™' * substance so apt by its swelling to burst the glass tubes that II. acidimetry. -,JK^T ^^'^^^^^ ^^^^^^' *^^* ^*^" ®^ ammonia of standard strength, faintly tinted With ntmus, affords a most exact and convenient acidimeter, when poured or let fall I«°S«*t f nn^^ • ^'^°PPi«S-t»l>e. Bicarbonate of potash also, when dissolved in water, so that 1,000 gram measures contam one atom of the salt counted in grains, is a good test-hquor for the same purpose ; for if the centigrade measures expended ii effectine n,!oir» ^^*'**'' "^ multiplied by the atomic weight of ihe ^iven acid, the product is thi quantity m grams of acid present. » f ^^ r.fil^t^'^'^ ^""lu^ likewise exactly performed by measuring in the cylindric gas- meter (^g. 6) the volumes of carbonic acid gas disengaged from pure bicarbonate ol potash or soda, by a given weight of any acid, taking care to use a small excess of the f}l' JnS ^°'"/^^'»Pl«» 16-8 g'^ains o^ dry and 20f of hydrated sulphuric acid disen- gage 10,000 water grain measures of gas from bicarbonate of potash. Therefore, if 20* grams of a given sulphuric acid be poured into the flask of^g. 6, upon about 50 grains of the bicarbonate, powdered and covered with a little water, it will cause the evolution of a volume of gas proportioned to its strength. If the acid be pure oil of vitriol, that weight of it will disengage 10,000 grain measures of gas; but if it be weaker, so much less gas— the centigrade measures of which will denote the per-cent- age value of the acid. If the question be put, how much dry acid is present per cent, m a given sulphuric acid, then 16-8 grains of the acid under trial must be used; and the resulting volume of carbonic acid gas read on the scale wiU denote the per-cekta«e of dry acid.f *^ * For nitric acid, we should take 22-6 grains; for hydrochloric ormuriaUc acid, 15-34 ; for acetic acid, 21-6 ; for citric acid, 24-6 ; for tartaric acid, 28 grains: then in each case we shaU obtain a volume of carbonic acid gas proportioned to the strength and punty of these acids respectively. The nitric, hydrochloric, and acetic acids are re- ferred to m their anhydrous state ; the tartaric and citric in their crystalline. If the latter two acids be pure, a solution of 24-6 grains of the first and of 28 of the last * 1,000 water grain measures of sulphuric acid of specific gravity 1-032, or 32 above water, neutralize 32 grains of soda, and, consequenUy, one atom, on the hydrogen scale, of each of the other basM reckoned in grains. "mci ua9«^. Having in the course of many years subjected my tables of sulphuric, nitric, and muriatic acids as well as of ammonia, to strict cross-examination, 1 have found them trustworthy for all alkalimetric^ and acidimetncal purposes. ' aiAJuunemcai ^JtA^^^^ bicarbonate must be free from carbonate, a point easily secured by washinr its powder with cold water, and drying it in the air. ^ j j ^mmum^ »• |wwaer wiu will disengage from 60 grains of bicarbonate of potash 10,000 grain measures of car- bonic acid gas.* , . . • • ,. • ij i> Acidimetrical operations may likewise be performed by determining the weight of carbonic acid gas expelled from the bicarbonate of potash or soda, by a given quantity of any acid, in the apparatus either ^g. 7, or fig. 8. Here the weights to be takea are as follows, in reference to Grains. 9-127 12-33 8-29 11-67 13-31 15-13 Dry Sulphuric acid - - - " Nitric " Hydrochloric - - - ** Acetic - - - - Crystallized Tartaric - - - « Citric . - - Each of these quantities of real acid, with 25 or 26 grains of bicarbonate of potash, will give off 10 grains of carbonic acid gas ; and hence whatever weight the apparatus loses, being reckoned in grains and tenths of a grain, denotes the per-centage of acid in the sample under trial, without the ne- cessity of any arithmetical reduction. Pei-sons accustomed to the French metrical system may use deci-grammes instead erf" grains, and they will arrive at the same per-centage results. The preceding experiments, in reference to the weight of car- bonic acid gas expelled for the purpose of either alkalimetry or acidimetry, may also be made by means of the ordinary apparatus represented in jig. 9. a is a small matrass which contains the acid or carbonated alkali at its bottom ; and conversely the alkali or acid, for their mutual decomposition in the small test-tube, shown first at h nearly upright and filled, but afterward at a, horizontal and emptied, b is a bulbous tube filled with frag- ments of chlorcalcium for absorbing the aqueous vapor that rises with the carbonic acid gas, and c{ c is a small bent tube which dips into the Uquid in the matrass. The weighings, &.C., may be conducted as already detailed ; and when the effer- vescence is completed, the residuary gas is sucked up through B, while the atmospheric air enters to replace it at the orifice d of the bent tube. The NEW methods which pervade the whole treatise of Drs. Fresenius and Will are all based on the principle of estimating alkalinity, acidity, and the oxygen in manganese (or chlorom- etry) by the weight of carbonic acid gas evolved. As in taking these measures the gas must be discharged without carrying water off with it, an elegant and ingenious little piece of apparatus has been invented by the authors for effecting that purpose, and it will do it well, a and b (^g. 10) are two flasks (wide-mouthed medicine-bottles may be employed), a must have a capacity of from 2 ounces to 2| ounces of water ; it is advisable that b should be somewhat smaller, say of a capacity of about 1 to \\ ounces. Both flasks are closed by means of doubly perforated corks. These perforations serve for the reception of the tubes a, c, and d, c is a tube bent twice at right angles, which enters at its one end just into the flask a, but descends at its other end, near to the bottom of b. These tubes are open at both ends when operating ; except the top end 6 of the tube a, which is closed by means of a pellet of wax. The substance to be ex- amined is weighed and put into the flask a, into which water is then poured to the extent of one third of its capacity. b is filled with common English sulphuric acid to about half its capacity. Both flasks are then corked (by which they be- come united by the rectangular tube), and the ap- paratus is weighed. The air of the whole apparatus is next rarefied by applying suction to the tube d : the consequence is, that the sulphuric acid contained in b ascends into ^* The expulsion of the gat may be completed by surrounding the flask with a towel dipped in hot 40 ALKALIMETRY. Jntn n^nt '♦ I "u " ^J^'''' **^ ^^ ^^^^ ovcr into B. Immediately upon its coming into contact with the carbonate contained in a, carbonic acid gas is disengaged and in Its escape must necessarily traverse the oU of vitriol in b, and therein deposite all its aqueous vapor before issuing from d. The sulphuric acid in passing over into a heats tne mixture at the same time, and thus promotes the expulsion of the gas. Whenever this ceases to flow, a little more sulphuric acid must be sent over into a by suction irom rf (or rather from a recurved tube attached, pro tempore, to it) ; an artifice which may be repeated till no more gas can be expelled, even when the contents of a are Heated, as they must be at the end by the excess of oil of vitriol. *• From the aperture 6 of the tube a, which has been aU the time closed, the bit of wax IS now to be removed, and to the tube connected with d, suction is to be applied, tUl all the carbonic acid lodged in the apparatus be replaced by atmospheric air. The whole is to be then cooled, wiped, and weighed; the loss of weight indicates exactly Uie quantity of carbonic acid which existed in the carbonate submitted to experiment Ihe process is no less neat than it is simple, and does honor to the ingenuity of its in- ventors. Their mode of deducing the percentage of alkali from the quantity of carbonic acid discharged m the operation is also quite exact, and suitable for con- tinental chemists familiar with gramme weights and calculations, but certainly not for persons conversant only with ounces, drams, and scruples, or even with grain subdi- visions. The whole book, however excellent, needs, for the British public, transpo- «tion, before It can serve in this country the purpose intended by its scientific authors. Ihus, in section 4, where several results of their analyses are given, the statements have a somewhat mysterious aspect. Should any one ask why the oracular number of 4-83 grammes of carbonate of soda is used as their standard wei-ht for analysis, he can obtain no response in the book, either in a note or anywhere else. A Germai or fw"i c? ' familiar with chemical computation, will probably be able to discover mat 4-8d grammes of pure carbonate of soda contain, by Berzelius's tables of atomic weights, 2 grammes of carbonic acid; for 53-47 (1 atom of carbonate) : 22-15 (1 of carbonic acid) : : 4-83 : 2-00. Such is the simple solution of this apparent enigma, and of some other similar puzzles in the book. Indeed, unless the reader is aware of tfiat proportion, he can not see the grounds of the accordance in the results between experiment and theory, or why the numbers 2-010, 1.993, and 2-020, are presented as specimens of great precision. This accordance gives satisfaction when it is known that these numbers, in experiments 1, 2, and 3, oscillate on one side or other so near to A aar^'^^n- "''°"^^'" ^'^^' ^"^ ^ grammes and 83 centi-grammes, as also 1 gramme and yy5 miUi-grammes, are awkward weights^ for an ordinary English chemist or apothecary, which would require a month or two's residence in the laboratories of tfiessen and Pans to manipulate with readiness. Again, m testing carbonate of potash, our authors take 6-29 grammes as their unity of weight, undoubtedly, because, if pure, it should discharge, by saturation with the sul- phuric acid, 2 grammes of carbonic acid. Here, however, they have not stuck so rigidly as the school of Giessen usually does to Berzelius's atomic numbers; for his atom of o^c^i! oL'^il^^ '^ ^^'^2 5 whence, 22-15 : 69-42 : : 2-00 : 6-68, hydrogen = 1-00 : or 276-44 : 866-33 : : 2-00 : 6-268 oxygen = 100. ' Admitting the value of the new method in testing neutral carbonates, it can not be airecijy applied to the mixed carbonate and bicarbonate of soda, so commonly sold in this country for bicarbonate; nor is it applicable to the case of a mixture of caustic and carbonated alkali, without the tedious process of previous treatment with car- bonate of ammonia and heat. The new German method of acidimetry consists in determining how much carbonic acid gas is disengaged from a standard bicarbonate of soda, by a given weight of any acid. The twin-flask apparatus (Jig. 10) is used. The weighed portion of acid is put into a, and a sufficient quantity of the soda into a test-tube, which is suspended upright with a silk thread fastened by the pressure of the cork to the mouth of the flask. On letting the thread loose, the test-tube falls, and the cork being instantly re- placed, the whole gas evolved is forced to pass through the sulphuric acid in b, and there to deposite its moisture. The experiment is conducted in other respects as already described lor alkalimetrj'. The following extract from Drs. Fresenius and Will's New Methods of jSUealimetn/t &c., will show the Giessen plan of calculating results :— " The amount of anhydrous acid contained in the hydrated acid under examination IS determined from the amount of carbonic acid escaped, as follows : — "Two measures of carbonic acid bear the same proportion to one measure of the anhydrous acid in question, as the amount of carbonic acid expelled does to the amount sought of anhydrous acid. Thus, let us suppose, for instance, we have examined dilute sulphuric acid, and obtained 1-5 grammes of carbonic acid, the arrangement would he : — '; ALKALIMETRY. 550 (2 X 275) : 501 = 1-5 : x x=l-36. 41 The amount of sulphuric acid operated upon consequently would contain 1-36 eramraes of anhydrous acid. Let us suppose the weight of this amount to have been 15 grammes, the sulphuric acid under examination would contain a per-centage amount of 9*06 ; for 15 : 1-36 = 100 : x a; =9-06."* « Section XXIX. Stating the Quantities of the various Jcids to be used in their Examination. — To enable our readers at once, without the trouble of calculation, to determine from the weight of carbonic acid expelled, the exact amount of anhydrous acid contained in those acids which are of most frequent occurrence, we have subjoined lists of certain quantities to be taken of each acid for experiment, so that the number of centi-grammes of carbonic acid expelled will directly indicate the per-centage amount of anhydrous acid in the acid under examination. " Multiples of those weights may of course be substituted for the numbers given, according to the degree of dilution of the acid under examination. In such cases the number of centi-grammes of the carbonic acid expelled must be divided by the same number, which has served as the multiplier. " These numbers are obtained by dividing the atomic weight of the acid by 550 (2 X 275, one eq. of carbon),t as follows : — "Two eq. of carbonic acid, corresponding to one eq. of the acid to be exam- ined, how much should be taken of the latter to expel 1-00 grammes of carbonic acid? ** The arrangement of sulphuric acid, for instance, is as follows : — 550 : 501 = 1-00 : x x=:0-91 (or, more correctly, 0-911). " When examining acids, it is most advisable to use that multiple of the unity (ac- cording to the degree of concentration) which will expel from one to two grammes oi caibonic acid. "l. SULPHURIC ACID. " Unity 0-91 grammes (or, more correctly, 0*911 grammes). ** Multiples : — 2 X 0-911 = 1-822 grammes. 3 X 0-911 = 2-733 (C 4 X 0-911 = 3-644 (C 5 X 0-911 — 4-555 « 6 X 0-911 = 5-466 « 7 X 0-911 = 6-377 « 8 X 0-911 = 7-288 « 9 X 0;911 = 8-199 « 10 X 0-911 = 9-110 « 15 X 0-911 = 13-665 (C 20 X 0-911 = 18-220 (t 30 X 0-911 = 27-330 « &c. "Thus, knowing that 0-91 of anhydrous sulphuric acid will expel 1-00 of carbonic acid, it will be easy to determine what multiple ought to be used, according to the de- gree of concentration of the acid to be examined."! ni. CHLOKOMETRY, ^thd the testing of Black Oxide of Manganese for its available Oxygen, The value of manganese may be estimated very exactly by measuring the quantity of chlorine which a given weight of it produces with hydrochloric acid ; the chlorine boing at the same time estimated by the quantity of solution of green sulphate of iron, which it will peroxidize. A process of this kind was long ago practised with chloride of lime (bleaching powder or liquor) by Dr. Dal ton; and it has been since improved by Mr. Waltercrum. As the conversion of two atoms of green sulphate of iron into red sulphate requires only one atom of oxygen, this change may be effecti^d by the reaction of one atom of chlorine in liberating one atom of oxygen, while this appro- priates one of hydrogen from the hydrochloric acid. ♦ Nev Methois of Alkalimetry, «fc., pp. 93, 94. t A typofnnphical error in Mr. Bullock's edition ; it should be carbonic acid. tlfeto Methods of Alkalimetry, ^., pp. 103-105. 4S I I ALKALIMETRY. 4 and this weight is eqJvilen? to 3^6 ^o Am "-^^ = ^S^ ^ ^^ of wate^^ 726 ^X-^OTfi^ ,^ manganese to be testeTanS in'?o^hV\^K' ^^^ ^'»« ^^the of t? a^^alin^etrical tubi Xg^ej^thfooo .^' '^^ ^^^^ «"^ of the above equivalent codhp^ witn i,000 grain measures grain measures, according ?o^h '^"*'°"' ^^^"^ 200 to 500 manganese; then introduci through thoT'^'^i'i"*^'*^ «^ th« chloric acid of known specificTmvitv / """'^ ^' '^'"^ ^^^^^0- ing nearly 20 per cent, of chS^ <^"PP«f^ ^O, contain- f^^a^i'^etrical tube, and apply Jen ?el.!f/''T * *^^"&«* the flask by placing it in a ^cfnsu ! nf /'' '^^ *^"«" ^^ a spira-lamp. The%hlorine evo ved In?''- ''^"'""^ *>^«' the tube/, which passes merely bpynnri "'^ ."P ^^"'"^^ enter into the solution in b and / "n ^^^^«''f» and will sulphate. Have ready some drv . ' *^?"l«rting it into red of red ferrocyanide of p"oJass?um Tred"*'"'^ -^^'^ «*>^"^i«° Dip a slip of whalebone into X r P'^V^S'ate of iron). «irough the funnel e (represent^S it^'ir' «" '^^ 8^«»>« ^» high above the globe), and touch ihp ^^"^^ ™'^^^ ^«> As long as it forms a blue snLt ^ E^P^' ^^^^ ^ts point, as black oxide, and the ^roe^ss Tto bV' "7.^'" "^«^» dition of a little more hydrochloW. » ^^ "'^^'^ ^^^ ^^^^ ^^' ?s long as chlorine gas coni'nuei to K '^- ^° ^^^ "manganese. It maintains the level of the Li^nr • '^'''"^.^^^**' *"^ ^^^le Whenever the liquor, by the ri^t^ ' r 1 *^^^^ ^at in b. to stain the test-paper blue! morl of ?hV'%^^^""'15> ceases graduated tube must be added till it k •'''^"*''*". ^'^°'° ^^e the cautious administration of thii,^^^^^?' ^^ *^« so- By one hand, and of the cTp^r^i litor^/^',^.^""' ""''^ «" '^^ of saturation will be aiWvS at ?n ."r*^^ other, the term nianganese has then produIS Til L ^f"- "'""^^«- The yield. The number of water^.n *=^^orine which it can of taking. 100^,^;n« 7 '^^ ^'*^'" measures of liquid and 1' ^ consume about 169 .aPfroif !?'^'**^^« «^°^ has probably arisen fm '"o^banum. and to very nearly 40 graiS ^ ALKALIMETRY. will generate as much chlorine as will peroxidize exactly 1,000 grain deerees by the test-tube of the copperas solution. But if the ma measures, or 100 manganese contain iiirio oVsO per cent, of peroxide, then 40 or 50 centigrade measures of the said Bolution will be equivalent to the chlorine evolved from it by the reaction of hydro- ''''if'the^obtect is on the other hand to obtain direct indications as to cAZonne then a test solution of copperas, containing 772 grains in 10,000 gram measures, w. 11 serve to show by the peroxidizement of each 10 gram measures, or of one degree of the cen- testimal scale of the test-tube, the reaction of one gram of chlorine available for bleadi!^, &c., in the chloride of lime or of soda, &c. The test solutions of copperas Bhould be kept in well-corked bottles, containing a little powdered sulphuret of iron at their bottom, which is to be shaken up occasionally in order to preserve the iron in the *^The mlnga^nese should always be treated with dilute nitric acid before submitting it to the above-described ordeal; and if it exhibits effervescence, 100 grains of it should be digested with the acid for a suflicient time to dissolve out all the carbonates present, then thrown upon a filter, washed and dried before weighing it for the testing opera- tion The loss of weight thereby sustained denotes the per-centage of carbonates, and if calcareous it will measure the waste of acid that would ensue from that source alone, in using that manganese for the production of chlorine. That manganese is most chlorogerwus which contains no carbonates, the least pro- portion of oxide of iron, and of sesquioxide of manganese. The plan of testing manganese with oxalic and sulphuric t cids was originally prac- tised by M. Berthier and Dr. Thomson, but is lately modified by Drs. Fresemus and Will, who employ oxalate of potash, as likely to aflTord more exact results. Thev pre- scribe a multiple by 3 of 993 milli-grammes = 2-979 grammes, as the quantity of manganese best adapted to experiment ; but this quantity will not be found convenient by ordinary British operators. . » i. I, therefore, take leave to prescribe the following proportions : Into the vessel a of my twin-globe apparatus (fig. 8), put 100 grains of the ground manganese under trial, along with 250 grains of oxalate of potash and a little water ; poise the whole la the scale of a balance; then, by gentle inclination, cause a little of the strong sulphuric acid to pass from b up into a. The oxygen thereby liberated from the manganese, reacting in its nascent state upon the oxalic acid, will convert it into carbonic acid gas ; which, in passing through b, will deposite its moisture before escaping into the air. Whenever the extrication ofgas ceases, after such a quantity of oil of vitriol has been introduced into the globe a, as both to complete the decomposition of the oxalic acid and to heat the mixture, withdraw the cork for a moment, to replace the carbonic acid with air, then cool, and weigh the apparatus. The loss of weight, in grains, will denote the per-centage value of the manganese; that is, the proportion per cent, of perfect peroxide in the sample. If the manganese be pure no black powder should remain. The preceding experiment is founded upon the following principle : One atom of peroxide of manganese = 44, contains one atom of oxygen separable by sulphuric acid, and capable of converting one atom of oxalic acid into two atoms of carbonic acid, also = 44, which fly oflT; and cause therefore a loss of weight equal to that of the whole peroxide. To one atom of oxalic acid, which consists of three atoms of oxygen, and two of carbon — if one atom of oxygen be added, the sum is obviously four atoms of oxygen and two of carbon = 2 atoms of carbonic acid. The apparatus (fig. 10) of Drs. Fresenius and Will will answer perfectly well for making the same experiment, the manganese being put into A, with about two and a half times its weight of oxalate of potash, and the sulphuric acid being drawn over into the mixture by suction, as above described. The economy of any sample of manganese in reference to its consumption of acid, in generating a given quantity of chlorine, may be ascertained also by the oxalic acid test: 44 grains of the pure peroxide, with 93 grains of neutral oxalate of potash, and 98 of oil of vitriol disengage 44 grains of carbonic acid, and afford a complete neutral solution ; because the one half of the sulphuric acid, = 49 grains, goes to form an atom of sulphate of manganese, and the other half to form an atom of sulphate of potash. The deficiency in the weight of carbonic acid thrown off will show the deficiency of peroxide of manganese ; the quantity of free sulphuric acid may be measured by a test solution of bicarbonate of potash, and the quantity neutralized, compared to the car bonic gas produced, will show, by the ratio of 98 to 44, the amount of acid unprofitabl/ consumed. 44 ALKALIMETRY. ALKALIMETRY. 45 I .Ja ^^\^' ^^ *^^^' ^> ™*y ^^0 ^ graduated, and may contain the quantity of orifice S'open^. °^ '"" '°''''''*' '° ^""^ °"'' '^ ^^ «^°P*^°^^ ^^ the top th J^'f.fn^*.! ''; ^''*? * ^"?^ *^ v"" ^^^' ^' ""^y ^« substituted with advantage for enough o?'Jj!i T^ ^' '^^' '""^W^^y ^l °^«de of such dimensions as to contaTn ZnnJ^ -^^r"* supersaturate the bases of the carbonates in the phial, a, there will be no necessity for a separate vessel to hold the decomposing acid. Thus the apDaralus becomes very light, convenient, and maybe placed in the s4ll scale of a fine Cce Mock ren'r "''"f '' ''''''' ^'''?^"^ ^"^ ^^" <^^- '^)^ '^ furnished tMr! ft?ument 7. r ""^"^ large pan or scale to stand in. I flatte? myself that the in- fst?Tnd\-h^; •!' •., "^^"J,^^'^' ^»" be found an acceptable present lo pracUcal chem- ^Inrno /li "k-^"^^^^^^^'" readily to examine, not only carbonates, but also manganese and bleaching substances, with great precision, by the weight of carbonic acid gas disengaged, on the principles above explained caroonic « « }?ftl!?L^'\^^''M\^PP*'^^'i' .^•^^- ^)' *"^^ t^e sulphuric acid is poured into lattei R7th ^ ^"^"^ ^.t ^^'m? ^^'^ ^' ^'^^'^ ^^^ carbonate is introduced into the ihoked ^y crrSe'saU.' "'^"^ '"'^^^ °' ^'^ ^"^^ ^"^^ ^ ^"^ ^^ ^« «Pt to get bv Mr ^uZJv^ ^"^t^t^o^Vl^^ ^'T ^^ ^°'^ «^ ^"- Fresenius and Will, as edited by Mr. Bullock for the English reader. An accurate comparison may thus be made o?emors!- "'''"' '''''''''' ^^" "^^^"^^ ^''^ °^^^« ^' t^^ practke of ordSaPy to "tJ^^7J.l'!J'^?V'A Examimtum of Manganese : having at the same time due regard to the amount of And required for its complete Decomposition.— We have stated ai Section 30, that it is not a matter of indifference, with regard to the amounfof ac?d employed m the production of chlorine from manganese, what are the Tnerals whfch of ourmPth"'/ '°if '•"' l^ ^^^^^^^^ with the peroxide. The following i^r^fi^at on of our method will g.ve the most correct information on this point :- Specific weight found. 1-8485 81-54 1-8480 81-13 1-8475 80-72 1-8467 80-31 1-8460 79-90 1-8449 79-49 1-8439 79-09 1-8424 78-68 1-8410 78-28 1-8393 77-84 1-8376 77-40 1-8356 77-02 Per-centage amount of anhydrous acid found. Amount to be used for the exami- nation. 6-708 6-742 6-776 6-811 •846 •881 -916 •951 -987 •027 7-067 7-101 Specific weight found. 6- 6- 6- 6- 6- 7- 1-8336 1-8313 1-8290 1-8261 1-8233 1-8206 1-8179 1-8147 1-8115 1-8079 1-8043 Per-centage amount of anhydrous acid found. Amount to be used for the exami- nation. 76-65 76-24 75-83 75-42 75-02 74-61 74-20 73-79 73-39 72-97 72-57 •136 •174 •213 •262 •291 •331 -371 •412 7-453 7-495 7-537 7- 7^ 7- 7- 7- 7- 7- 7- «„,?lLr f f« ! *J!^° P°"'^^ into A as will fill the flask to about one fourth : and, lastly, from 6-5 to 7 grammes of neutral oxalate of potash, or from 5-5 to 6 grammes of neutral oxalate of soda, are added; 2-98 grammes of the (finely-pounded) manganese to be examined are then weighed (the manganese must have been pre- viously tested for carbonate alkaline earths : compare this section at the end) into a small glass tube, such as used in acidimetry, and described in Section 25. About the aame quantity of pure pyrolusite,» in powder, is then put into another similar tube. The tube, with the manganese to be examined, is then suspended in a (M. lOX ai described at SecUon 26, and the apparatus prepared, as directed at Section 3. The if rt'onntLncIf *^ °^ pyrolusite will serve this purpose, provided it be free from other manganese ores Lfr^IliT^^ '"f^^Vv.^Jf ; '* "jay be employed directly ; but should it contain alumina or ifiSJ it musi ^thpn !,! l"^ "^'^i^J*""!^ nitric acd, at a gentle heat, until all soluble parts have been diTsolve? it for pylorus te'^' ArtificiaUy prepared, hydratcd pero.xide of mL^ganese may be suitUutad apparatus is then placed on one scale of a balance, together with the other Uttle tube ^«'^htlork?frir^^^^^^^ LmeXt raTsea to allow the little tube with the manganese "The co^k of A IS ^^£?^°^^7^jjQ^ of carbonic acid commences immedia ely, and to fall into ^^^.,^^^:.7^Zn^^^^^^ decomposed. When the operation begins to get continues until » J^J^.^^^^^^f ^jgXced in boiling water, and allowed to remain there on more slowly, the flask, a, is placea ;/J |;" | ^ '^ ^ then removed* from a, the until no more buf es aPPear The httle ^a^ ~.- ^^ ^ ^^,^ ^he sucked air flask, A, taken out of the ^^ J^^^J'/^^ ^^ ^ having been allowed to cool, astes no longer of carbomc ac a. ^ JV > ^^^^ ^^^ ^.^^^^ ^^^^ ^.^^ ^^ \' TJ'^n7er^^L l^^^ for the loss of carbonic acid. The lusite still ^^^°^,^i^''^eg required, divided by three, directly indicates the per-centage «r,^nt of peroI'deTf ml^^^^^^^^ ivide Section 32 . The centigrammes substituted ?oTthe Lss"^ of carbonic aci=d are then removed from the balance, and the little tube uu 1 ^frrncnlitP is throwu luto A. (The little wax-stopper must of course pre- "^'^v be^Kcedin% ?f no ^ of carbonic acid takes place, the mria'nese exarned c^^^^^^^ of pure pyrosulite, and the experiment is at an end. But Tnufd a fresh evolution of carbonic acid take place, the operation must be further conducted and brought to a close, exactly as just stated {vide supra). The apparatus L then replaced on the balance, with an additional weight of three grammes on the fame scak If this is sufficient to restore a perfect equilibrium, no oss of acid has iaken place; L manganese, indeed, contains other matters in admixture, but only S as do not consume any acid. But if the scale with the apparatu.s sinks, this is a Srtain sign that a portion of the acid has been lost by combining wi h the oxides which SemanTanese under examination contains. The number of centigrammes required S rS^orl the perfect equilibrium of the balance, multiplied by 0-6114, unmediately Lkates how much anhydrous sulphuric acid has been wasted m the decomposition of KK) parts of the manganese under examination. The same number multiplied by a!333 indicates the amount of acid wasted in every 100 parts of sulphuric acid em- ployed for ?he decomposition of the manganese in question. The same number, multi. puJd by 0-5552, indicate how much anhydrous hydrochloric acid would be wasted m Ihe decomposition of 100 parts of the manganese. The same number, multiplied by ^33, indicates also how much acid would be wasted in every 100 parts of hydrochloric acid employed for the decomposition of the manganese. « These figures result from the following equations :— «I. 275 (eqTof carbonic acid): 501 (eq. of sulphuric acid) = the carbonic acid ob- tained minus (in proportion to the sulphuric acid used) : x. x=ihis carbonic acid X |0 J, t. e. X 1*822. Thus, the number obtained for x indicates the amount of sulphuric acid corresponding to the amount of carbonic acid obtained minus. « II. 2-98 of manganese : 100=a: of equation I. : x. x=x of I. X Igf , i. «. X 0-33557. « The X of the first equation tells us how much sulphuric acid has been wasted without contributing to the decomposition of 2-98 grammes of the manganese ; the x of the second equation tells us the same for 100 parts of manganese. « If therefore, the amount of carbonic acid obtained minus be directly multiplied by the product of the quotients of I. and II., ^ 1-822 and 0-33557, 1. e. with 0-61141 (the number given above), the amount of anhydrous sulphuric acid wasted in the decomposition of every 100 parts of manganese will immediately be found. " III. 5-47 (the amount of sulphuric acid used) : 100=the a: of I. : x. x=thea: of I. X ij^, i. e. X 0-18282. "Of 5-47 of sulphuric acid, the x of I. has been wasted, 100 corresponds to the x olTII. . ^ V • " The X of ni. is, therefore, found directly by multiplying the amount of carbonic acid obtained minus with the product of the quotients, 1-822 and 0-18282, i. e.= 0-33301. ^ ^^ - , , "The figures for hydrochloric acid are found in the same manner (4'967 Dt hydro- chloric acid must be taken instead of 5-47 of the sulphuric acid)."t * •• This must of necessity be done while the flask is still standing in the hot water, or else the «ul« phurlc acid will recede upon the apparatus being removed from the hot water." t Ntw Methods of Alkalimetry, and of determining the Commercial Value of Acids and ManganeM. By Drs. C. B. FreseniuB and H WUl. Edited by J Lloyd Bullock : pp. 123-128. 46 ALLOY. i : h ground and mi^ed with a &tll IjJf JLt '' ^r^^*"'. ^*"^' garments, &c. The leaves, and Turkey. * ^"^'^ lin^ewater, serve for dyeing the tails of horses in Persia .nd^...^/7he1^^C^^ the^pi;STf c^n-s^^^^^^^^^^ 7^:1' tTenr ^T"^' '^' ^T^^''^'? n^L^onr S^^^^^^^^^^^^ "sr^-^^- ^^^ --« ^^-^ ofgJld^ali s i^^:?:itr;;^:^S^^ Thistermfonneny^-^iiiedaccinponnd of any two or more me als whatSrer Thl!T "^^^ •"' ^^'." "^^ °^^*°« ^^^ ^^'"PO""^ an aUoy of copper a^d zL^ and tvnp m '' ?™"^M' an alloy of copper and tin ; brass, alloys possess metallic lus^e 'even whin ^f. ' T f ^^ °^ ^-'^^ ^°^ antimony. All the exceUent conductors of h?at\ndeirctrTci^ II f^""" '1^'''' '^'^ ^'^ «P«^«^' ^^^ are more or less ductile 3leahlpptc^5 ' / ^•'^^'^ently susceptible of crj^stallizing ; metals different yfusibkTsu^^^^^^^^^ '.f^T'* ^"^ ^^^^ ^^^'^ *^«"«'«^ of emplified with brass and gonTmetd ' ' '" '*'' '"''^' ""^ ^"^^^ ^^^" ^«^' ^ ^^ «' me&S sretlWstt^U P-Portions of the simple component sugar with Water It LnrobabL fh^ II T P'^P^''^^^"' ^^f combinations of salt or atomic ratio, as is exemDlified in L^^L^ ^^ ^^'rP'^'Pf!'^' ^^^*^"" '« ^'^^ equivalent or One metal doesVoraZytndi^eenty^wT^^^^ m^L^ w'^ ^'^^ P'T-^^^"' respect by peculiar affinities- thnrXl ^^ V 5, "?^^*'' ^"' *' ^^ governed in this readily with go Id, copp^ and^ekd Tn ^ ^^r^^'y J^^te with iron, but it combines metals, the following dTff;rences ^av hi nn^r •""' *^' ^^^T 7''^ '^^''' <^onstituent less than that of the sepamte LTall L7l ' !^ ^'"''^'' ^^' ^""^"'^^ «^ ^^« «"«y « the contrary, the al by i^ Sly hfrSl; thanThTil^L"' T *. ^""^ 'TP^-^kable degree; on mercurial alloys or aL^a^aL';^^^^^^^^^^^^ --^»*"-ts. The Jet^mT^^^^^^^^^^^^^^ and in the Ialter,TrecXr of tt " r7^' r ^^' ^""T"' "^^^' *" approximation, union. The foUowin/tables of Wn«r! Pf'^^'^^'^^f';?™ jach other in the act of their detail :- '«"°^^n= tables of bmary aUoys exhibit this circumstance in experimental ALLOY. 47 Alloy, having: a den.ity grreatcr than the mean of their constiluenta. Gold and zinc Gold and tin Gold and bismuth Gold and antimony Gold and cobalt Silver and zinc Silver and lead Silver and tin Silver and bismuth Silver and antimony Copper and zinc Copper and tin Copper and palladium Copper and bismuth Lead and antimony Platinum and molybdinum Palladium and bismuth. Alloys havini? a density less than th« mean of their constituents. Gold and silver Gold and iron Gold and lead Grold and copper Gold and iridium Gold and nickel Silver and copper Silver and lead Iron and bismuth Iron and antimony Iron and lead Tin and lead Tin and palladium Tin and antimony Nickel and arsenic Zinc and antimony. i J^rthu^nt' mii::tirb^^^^^ r^'tv^i TJits! ^' •'^ ^"^^ ^r^*^^^ ^' -^^ «^ nity in their state of combination Of Ih^ fusibility is increased by mutual affi- fusible metal consistin-Ts n^ s of bV/ /k' k J^^^^^^^^le instance is afforded in the heat of boiling wafer or 212° Falthnrh^K^ ""^ l'-^^^ *"^ ^ «^^»"' ^^^^ ^^^^ at th.. its components ThouW be SM' Th'- ^^"^ ^^^ ?^^^'"^ ^"^^ ^^"'^ed from the mean of a ver>.irtrrct;lt when Tf^r^^^nTxL LT ma^H^"/^ "^°T ^""^^"^ '' ^'^^ jections, and for filling Ih'e hollows of Ss S C d?^^ '"" m any considerable degree, upon those ofZ X;JZ'^:-Ztl^^^^^^ instead of being rendered paler by a large addition of zinc, is thereby converted into the rich-looking pinchbeck metal. , /. ^ . , j By means of alloys, we multiply, as it were, the numbers of useful metals, and some- times give usefulness to such as are separately of little value. Since these compounda can be formed only by fusion, and since many metals are apt to oxydize readily at their melting temperature, proper precautions must be taken in making alloys to prevent this occurrence, which is incompatible with their formation. Thus, in combining tin and lead, rosin or grease is usually put on the surface of the melting metals, the carbon produced by the decomposition of which protects them, in most cases, sufficiently from oxydizement. When we wish to combine tin with iron, as in the tinning of cast-iron tea kettles, we rub sal ammoniac upon the surfaces of the hot metals in contact with each other, and thus exclude the atmospheric oxygen by means of its fumes. AVhen there is a notable difference in the specific gravities of the metals which we wish to combine, we often find great difficulties in obtaining homogeneous alloys ; for each metal may tend to assume the level due to its density, as is remarkably exemplified in alloys of gold and silver made without adequate stirring of the melting metals. If the mass be large, and slow of cooling, after it is cast in an upright cylindrical form, the metals sometimes separate, to a certain degree, in the order of their densities. Thus, in casting large bells and cannons with copper alloys, the bottom of the casting is apt to contain too much copper and the top too much tin, unless very dexterous manipulation in mixing the fused materials have been employed immediately before the instant of pouring out the melted mass. When such inequalities are observed, the objects are broken and re-melted, after which they form a much more homogeneous alloy. This artifice of a double melting is often had recourse to, and especially in casting the alloys for the specula of telescopes. When we wish to alloy three or more metals, we often experience difficulties, either because one of the metals is more oxydable, or denser, or more fusible, than the others, or because there is no direct affinity between two of the metals. In the latter predica- ment, we shall succeed better by combining the three metals, first in pairs, for example, and then melting the two pairs together. Thus, it is difficult to unite iron with bronze directly ; but if, instead of iron, we use tin plate, we shall immediately succeed, and the bronze, in this manner, acquires valuable qualities from the iron. Thus, also, to render brass better adapted for certain purposes, a small quantity of lead ought to be added to it, but this cannot be done directly with advantage : it is better to melt the lead first along with the zinc, and then to add this alloy to the melting copper, or the copper to that alloy, and fuse them together. We have said that the difference of fusibility was often an obstacle to metallic com- bination ; but this circumstance may also be turned to advantage in decomposing certain alloys by the process called eliquation. By this means silver may be separated from copper, if a considerable quantity of lead be first alloyed with the said copper ; this alloy is next exposed to a heat just sufficient to melt the lead, which then sweats out, so to speak, from the pores of the copper, and carries along with it the greater part of the silver, for which it has a strong affinity. The lead and the silver are afterwards sepa- rated from each other, in virtue of their very different oxydability, by the action of heat and air. One of the alloys most useful to the arts is brass ; it is more ductile and less easily oxydized than even its copper constituent, notwithstanding the opposite nature of the zinc. This alloy may exist in many different proportions, under which it has different names, as tombac, similor, pinchbeck, &c. Copper and tin form, also, a compound of remarkable utility, known under the names of hard brass, for the bushes, steps, and bearings of the axles, arbors, and spindles in machinery ; and of bronze, bell-metal, &c. Gold and silver, in their pure state, are too soft and flexible to form either vessels or coins of sufficient strength and durability ; but when alloyed with a little copper, they ac- quire the requisite hardness and stiffness for these and other purposes. When we have occasion to unite several pieces of the same or of different metals, we employ the process called solderingy which consists in fixing together the surfaces by means of an interposed alloy, which must be necessarily more fusible than the metal or metals to be joined. That alloy must also consist of metals which possess a strong affinity for the substances to be soldered together. Hence each metal would seem to require a particular kind of solder, which is, to a certain extent, true. Thus, the soldei for gold trinkets and plate is an alloy of gold and silver, or gold and copper ; that of silver trinkets, is an alloy of silver and copper ; that of copper is either fine tin, for pieces that must not be exposed to the fire, or a brassy alloy called hard solder, of which the zinc forms a considerable proportion. The solder of lead and tinplate is an alloy of lead and tin, and that of tin is the same alloy with a litUe bismuth. Tinning, gilding, and silvering may also be reckoned a species of alloys, since the tin, gold, and silver are superficially united in these cases to other metals. Metallic alloys possess usually more tenacity than could be inferred from their con- 48 ALLOY. ALLOY. 4f ll ! i: ll Ktituents; thus, an alloy of twelve parts of lead with one of zinc has a tenacity double that of zinc. Metallic alloys are much more easily oxydized thau the separate metals, a phenomenon which may be ascribed to the increase of affinity for oxygen which results from the tendency of the one of the oxydes to combine with the other. An alloy of tin and lead heated to redness takes fire, and continues to burn for some time like a piece of bad turf. Every alloy is, in reference to the arts and manufactures, a new metal, on account of its chemical and physical properties. A vast field here remains to be explored. Not above sixty alloys have been studied by the chemists out of many hundred which may be made; and of these very few have yet been practically employed. Very slight modifications often constitute very valuable improvements upon metallic bodies. Thus, the brass most esteemed by turners at the lathe contains from two to three per cent, of lead ; but such brass does not work well under the hammer ; and, reciprocally, the brass which is best under the hammer is too tough for turning. That metallic alloys tend to be formed in definite proportions of their constituents is clear from the circumstance that the native gold of the auriferous sands is an alloy with silver, in the ratios of 1 atom of silver united to 4, 5, 6, 12 atoms of gold, but never with a fractional part of an atom. Also, in making an amalgam of 1 part of silver with 12 or 15 of mercury, and afterwards squeezing the mixture through chamois leather, the amalgam separates into 2 parts : one, containing a small proportion of silver and much mercury, passes through the skin ; and the other, formed of 1 of silver and 8 of mercury, is a compound in definite proportions, which crystallizes readily, and remains in the knot of the bag. An analogous separation takes place in the tinning of mirrors ; for on load- ing them with the weights, a liquid amalgam of tin is squeezed out, while another amal- gam remains in a solid form composed of tin and mercury in uniform atomic proportions. But, as alloys are generally soluble, so to speak, in each other, this definiieness of com- bination is masked and disappears in most cases. M. Chaudet has made some experiments on the means of detecting the metals of alloys by the cupelling furnace, and they promise useful applications. The testing depends upon the appearances exhibited by the metals and their alloys when heated on a cupel. Pure tin, when heated this way, fuses, becomes of a grayish black color, fumes a little, exhibits incandescent points on its surface, and leaves an oxyde, which, when withdrawn from the fire, is at first lemon-yellow, but when cold, white. Antimony melts, preserves its brilliancy, fumes, and leaves the vessel colored lemon-yellow when hot, but colorless when cold, except a few spots of a rose tint. Zinc burns brilliantly, forming a cone of oxyde ; and the oxyde, much increased in volume, is, when hot, green- ish, but when cold, perfectly white. Bismuth fumes, becomes covered with a coat of melted oxyde, part of which sublimes, and the rest enters the pores of the cupel ; when cold, the cupel is of a fine yellow color, with spots of a greenish hue. Lead resembles bismuth very much ; the cold cupel is of a lemon-yellow color. Copper melts, and be- comes covered with a coat of black oxyde ; sometimes spots of a rose tint remain on the cupel. Alloys.— Tin 75, antimony 25, melt, become covered with a coat of black oxyde, have very few incandescent points; when cold, the oxyde is nearly black, in con- sequence of the action of the antimony : a -^qq part of antimony may be ascertained in this way in the alloy. An alloy of antimony, containing tin, leaves oxyde of tin in the cupel : a jqq part of tin may be detected in this way. An alloy of tin and zinc gives an oxyde which, while hot, is of a green tint, and resembles philosophic wool in appearance. An alloy containing 99 tin, 1 zinc, did not present the incandescent points of pure tin, and gave an oxyde of greenish tint when cold. Tin 95, bismuth 5 parts, gave an oxyde of a gray color. Tin and lead give an oxyde of a rusty brown color. An alloy of lead and tin, containing only 1 per cent, of the latter metal, when heated, does not expose a clean surface, like lead, but is covered at times with oxyde of tin. Tin 75, and copper 25, did not melt, gave a black oxyde : if the heat be much elevated, the under part of the oxyde is white, and is oxyde of tin ; the upper is black, and comes from the copper. The cupel becomes of a rose color. If the tin be impure from iron, the oxyde produced by it is marked with spots of a rust color. The degree of affinity between metals may be in some measure estimated by the greater or less facfity with which, when of different degrees of fusibility or volatility, they unite, or with which they can, after union, be separated by heat. The greater or less tendency to separate into difl'erently proportioned alloys, by long-continued fusion, may also give some information upon the subject. Mr. Hatchett remarked, in his elaborate researches on metallic alloys, that gold made standard with the usual precaul tions, by silver, copper, lead, antimony, &c., and then cast, after long fusion, into vertica- bars, was by no means a uniform compound ; but that the top of the bar, corresponding to the metal at the bottom of the crucible, contained the larger proportion of gold. Hence, for a more thorough combination, two red-hot crucibles should be employed, and the liquefied metals should be alternately poured from the one into the other. To pre- vent unnecessary oxidisement from the air, the crucibles should contain, besides the metal, a mixture of common salt and pounded charcoal. The metallic alloy should also be occasionally stirred up with a rod of pottery ware. The most direct evidence ol a chemical change having been effected in alloys i% when the compound melts at a lower temperature than the mean of its ingredient*. Iron, which is nearly infusible, acquires almost the fusibility of gold when alloyed with this precious metal. The analogy is here strong with the increase of solubility which salts acquire by mixture, as is exemplified in the difficulty of crystallizing residuums of saline solutions, or mother waters, as they are called. When there is a strong affinity between the two metals, their alloy is generally denser than the mean, and vice versd. This is exemplified in the alloys of copper with zinc and tin on the one hand ; and with copper and lead on the other. When one of the metals is added in excess, there 'result an atomic compound and an indefinite combination, as would appear from Muschenbroek's experiments. Thus, 1 of lead with 4 of silver give a density of 10"480. 1 do 2 do 11-032. 1 do 3 do 10-831. The proportion of the constituents is on this principle estimated in France by the tea of the ball applied to pewter ; in which the weight of the alloyed ball is compared with that of a ball of pure tin or standard pewter cast in the same mould. Alloys posseee the elasticity belonging to the mean of their constituents, and also the specific caloric According to M. Rudberg, while lead solidifies at 325° C, and tin at 228°, and their atomic alloy at 187°, which he calls the fixed point, for a compound Pb Sns. The action of the air is in general less on alloys than on their components ; to which, however, there are remarkable exceptions, as for example, with the alloy of 3 parts of lead and 1 of tin, which when heated to redness burns briskly into a red oxide. When two metals, as copper and tin, are combined, which oxidize at different temperatures, they may be separated by fusion with exposure to the air, an artifice practised on the church bells in France to procure tin for making cannon metal bronze. Cupella- tion of the precious metals is a like phenomenon. An alloy too slowly cooled is often apt to favor the crystallization of one or more of its components, and thus to render it brittle ; and hence an iron mould is prefer- able to one of sand when there is danger of such a result It is not a matter of indifference in what order the metals are melted together in making an allo}^ Thus, if we combine 90 parts of tin and 10 of copper, and to this alloy add 10 of antimony; or if we combine 10 parts of antimony with 10 of copper and add to that alloy 90 parts of tin, we shall have two allovs chemically the same' and still It will be easy to discover that, in other respects, fusibility, tenacity Ac' they totally differ. Whence this result ? Obviousl v from the nature of their combi- nation dependent upon the order pui-sued in the preparation, and which continues after the mixture. In the alloys of lead and antimony also, if the heat be raised in combininj; the two metals together much above their fusing points, the alloy become* harsh and brittle; probably because some alloy formed at that high temperature is not soluble in the mass. ^ In common cases the specific gravity affords a good criterion whereby to judge of the proportion of two metals in an alloy. But a very fallacious rule has been given in some respectable works for computing the specific gravity that should result from the alloying of given quantities of two metals of known densities, supposing no chemical condensation or expansion of volume to take place. Thus, it has been taught, that if gold and copper be united m equal weights, the computed specific gravity is merely the arithmetical mean between the numbers denoting the two specific gravities. Whereas the specific gravity of any alloy must be computed by dividing the sum of the two weights by the yum of the two volumes, compared, for convenience sake, to water reckoned unity. Or, !II/"°^^'. 7\!.\'""^^'"^y.5^'^^^^^ thus :-Multiply the sum of the weights into the products of the two specific-gravity numbers for a numerator; and multiply each fShl?'*'' !i"""°'^^'/"^°^ifu''"=^^ ^^ ^^^ «^^^^ body, and add the two products together for a denominator. The quotient obtained by dividing the said numerator br n„r:nr''"!l"?w' f ^ -^ truly computcd mean specific gravity of the alloy. On com- paring with that density, the density found by experiment, we shall see whether expan- ^npnJfi'/r^r r^n£''''^?"'^^^'^"^''^^^**'^'"^tallic Combination. Gold having a specific gravity of 19-36, and copper of 8-87, when they are alloyed in equal weights, give, by the fallacious rule of the arithmetical mean of the densities ^9-36 + 8-8 7 _ ^rZTthhrtf^J^^ computed mean density is only 12-16. It is evident that, on com- Sfious condJn!" • ""^/^P^'^"^^"^ ^e should be led to infer that there h'ad been a prodigious condensation of volume, though expansion has actuaUy taken place. Lei \'\ 1» 50 ALUM. ALUM. 61 W, w be the two weights ; P, p the two specific gravities, then M, the mean specific eravitv, is given by the formula M-^-^^±^5lZP...2A = -i?^)=twice Pw-fpW P + p the error of the arithmetical mean ; which is therefore always m excess. Alloys of a somewhat complex character are made by Mr. Alexander Parkes, of Birmingham, of a white or pale color, by melting together 33 i lbs. of foreign zinc, 64 of tin, 1^ of iron, and 3 of copper ; or 50 zinc, 48 tin, 1 iron, and 3 copper ; or any m- termediate proportion of zinc and copper may be used. The iron and copper are first melted together in a crucible, the tin is next introduced, in such quantities at a time as not to solidify the iron and copper ; the zinc is added lastly, and the whole mixed by stirring. The flux recommended for this alloy is 1 part of lime, 1 part of Cumber- land (iron ?) ore, and 3 parts of sal ammoniac. Another of his alloys is composed of 66 lbs. of foreign zinc, 33i tin, 3^ antimony; or 70| zinc, I9J tin, and 2| antimony; or any intermediate proportions, and with or without arsenic. He uses black flux. When to be applied to the sheathing of ships, from 8 to 16 oz. of metallic arsenic are added to every 100 lbs. of alloy. A third class of alloys consists of equal parts of iron and nickel ; the copper is next added, and lastly the zinc, or the copper and zinc, may be added as an alloy. 100 lbs. may consist of 45i lbs. of iron and nickel (parten cequalex), and lOJ lbs. of foreign zinc ; or 30| lbs. of alloy of iron and nickel {p. (b.\ 46 copper, and 26i zinc ; or any intermediate propor tions of zinc and copper. He uses also an alloy of 60 lbs. of copper, 20 of zinc, and 20 of silver; or 60 copper, 10 nickel, 10 silver, and 20 zinc; the copper and nickel being first fused together. His fifth alloy is called by him a non-conductor of heat ! It is made of 25 nickel, 25 iron, and 50 copper; or 15 nickel, 25 iron, and 60 copper; the last being added after the fusion of the others. Mr. Parkes also proposes to deposit metals by means of electricity from their iodides, chlorides, and phosphates, while in fusion by heat, either singly or combined with compatible haloids. ALMOND. {Amande,Yr.; Mandel,GeTm.) There are two kinds of almond which do not differ in chemical composition, only that the bitter, by a curious chemical re- action of its constituents, generates in the act of distillation a quantity of a volatile oil, which contains hydrocyanic acid. Vogel obtained from bitter almonds 8*5 per cent, of husks. After pounding the kernels, and heating them to coagulate the albumen, he procured, by expression, 28 parts of an unctuous oil, which did not contain the smallest particle of hydrocyanic acid. The whole of the oil could not be extracted in this way. The expressed mass, treated with boiling water, afforded sugar and gum, and, in conse- quence of the heat, some of that acid. The sugar constitutes 6*5 per cent, and the gum 3. The vegetable albumen extracted, by means of caustic potash, amounted to 30 parts : the vegetable fibre to only 5. The poisonous aromatic oil, according to Robi quet and Boutron-Charlard, does not exist ready-formed in the bitter almond, but seems to be produced under the influence of ebullition with water. These chemists have shown that bitter almonds deprived of their unctuous oil by the press, when treated first by alcohol, and then by water, aff"ord to neither of these liquids any vola- tile oil. But alcohof dissolves out a peculiar white crystalline body, without smell, of a sweetish taste at first, and afterwards bitter, to which they gave the name of amyg- daline. This substance does not seem convertible into volatile oil. See Amygdaunk. Sweet almonds, by the analysis of Boullay, consist of 54 parts of the bland alnriond oil, 6 of uncrystallizable sugar, 3 of gum, 24 of vegetable albumen, 24 of woody fibre, 5 of husks, 35 of water, 05 of acetic acid including loss. We thus see that sweet almonds contain nearly twice as much oil as bitter almonds do. ALMOND OIL. A bland fixed oil, obtained usually from bitter almonds by the action of a hydraulic press, either in the cold, or aided by hot iron plates. See Oil. ALOE. A series of trials has been made within a few years at Paris to ascertain the comparative strength of cables made of hemp and of the aloe from Algiers ; and they are said to have all turned to the advantage of the aloe. Of cables of equal size, that made of aloe raised a weight of 2000 kilogrammes (2 tons nearly) ; that made of hemp, a weight of only 400 kilogrammes. At the exposition of objects of national in- dustry, some years ago, in Brussels, I saw aloe cordage placarded, as being far prefer- able to hempen ; but I believe without just grounds. ALUDEL A pear-shaped vessel open at each end, of which a series are joined for distilling mercury in Spain. See Meecuby. ALUM. {Alun, Fr. ; Alaimi, Germ.) A saline body, consisting of the earth of clay, called alumina by the chemists, combined with sulphuric acid and potash, or sulphuric acid and ammonia, into a triple compound. It occurs in the crystallized form of octahe- drons, has an acerb subacid taste, and reddens the blue color of litmus or red cabbage. .Uum works existed many centuries ago at Roccha, formerly called Edessa, m Syria, whence the ancient name of Roch alum given to this salt. It was afterwards made at Foya Nova, near Smyrna, and in the neighborhood of Constantinople. The Genoese, and other trading people of Italy, imported alum from these places into western Europe, for the use of the dyers of red cloth. About the middle of the fifteenth centurj', alum began to be manufactured at La Tolfa, Viterbo, and Volaterra, in Italy ; after which time the importation of oriental alum was prohibited by the pope, as detrimental to tlie interests of hi* dominions. The manufacture of this salt was extended to Oermany at the begin- ning of the sixteenth century, and to England at a somewhat later period, by Sir Thomas Chaloner, in the reign of Elizabeth. In its pure state, it does not seem to have been known to the ancients ; for Pliny, in speaking of something like plumose alum, says, that it struck a black color with pomegranate juice, which shows that the green vitriol was not separated from it. The stypteria of Dioscorides, and the alumen of Pliny, comprehended, apparently, a variety of saline substances, of which sulphate of iron, as well as alumina, was probably a constituent part. Pliny, indeed, says, that a substance called in Greek *Yypa, or watery, probably from its very soluble nature, which was milk-white, was used for dyeing wool of bright colors. This may have been the mountain butter of the German mineralogists, which is a native sulphate of alumina, of a soft texture, waxy lustre, and unctuous to the touch. The only alum manufactories now worked in Great Britain, are those of Whitby, in England, and of Hiurlett and Campsie, near Glasgow, in Scotland ; and these derive the acid and earthy constituents of the salt from a mineral called alum slate. This mineral has a blueish or greenish-black color, emits sulphurous fumes when heated, and acquires thereby an aluminous taste. The alum manufactured in Great Britain contains potash as its alkaline constituent ; that made in France contains, commonly, ammonia, either alone, or with variable quantities of potash. Alum may in general be examined by water of ammonia, which separates from its watery solutions its earthy basis, in the form of a light flocculent precipitate. If the solution be dilute, this precipitate will float long as an opalescent cloud. If we dissolve alum in 20 parts of water, and drop this solution slowly into water or caustic ammonia till this be nearly, but not entirely, saturated, a bulky white precipitate will fall down, which, when properly washed with water, is pure aluminous earth or clay, and dried forms 10-82 per cent, of the weight of the alum. If this earth, while stdl moist, be dissolved in dilute sulphuric acid, it will constitute, when as neutral as possible, the sulphate of alumina, which requires only hvo parts of cold water for its solution. If we now decompose this solution, by pouring into it water of ammonia, there appears an insoluble white powder, which is subsulphate of alumina, or basic alum: and contains three times as much earth as exists m the neutral sulphate. If, however we pour into the solution of the neutral sulphate of alumina a solution of sulphate of potash, a while powder wiU fall if the solutions be concentrated, which is true alum : but If the solutions be dilute, by evaporatmg their mixture, and cooUng it, cn-stals of alum will be obtained. When newly precipitated alumina is boiled in a solution of aliun, a portion of the eaith enters mto combination with the salt, constituting an insoluble compound, whish foUs in the form of a white powder. The same combmation takes place, if we decom- pose a boilmg hot solution of alum with a solution of potash, till the mixture appears ^n^^tnTni T V*''°'"' P^'P"'- ..™'. ^^^"^"^^^ ""^ ^^«i^ ^1"°^ ^^i«ts native in the ^Zh. r^r ^''^^ i'.Tn^v'''?* ^^r^**' ^"^ '^ ^«'^«i^ts in 100 parts of 19-72 parts of Sn^in k^ ^Tf' 61-99 basic sulphate of alumina, and 18.29 wat^. When this Z the cfrvSf. h^^ * ^r' ^""'^'^'^r of sulphuric acid, it dissolves, and is converts! mto the crystallizable alum of commerce. These experimental facts develop the principles of the manufacture of alum which IS prosecuted under various modifications, for its important uses in the arts AlSn ^Idom occurs ready-formed in nature; occasionaUy, as^an efflorescence on stone';, and^ rrf^Si^^lTv^TJ ""?' "^ ,? '^^. ^^'' J^^^- "^^^ ^"^ «f European commerce is fabricated artificiaUy,ei her from the alum schists or stones, or from clay. The mode of manufactur/' differs accordmg to the nature of these earthy compounds. Some of them such asTe wSit mlirh'r" h" %l ^^T"^^ '^ '^' ^^^^' ^"^ ^^^ ^^h othL ma ters from Tame^v Iv «nH if^. The schists contain only the elements of two of the constituents, namely, clay ar^d sulphur, which are convertible into sulphate of alumina, and this mav ^um It^^' i" V^^ ^7 ^^^^ '^^ ^^^^^^ ingredient. To this class belongTe alum-slates, and other analogous schists, containing brown coal. ^ fntL^'""'^^' T ""-^ *^^''''* ■^''"''^ *^' *^'"^" Stone.~The alum-stone is a rare mineral being z^ wheretfolTe^Z' t7°'''' %"' J 'T^^ ^ ""^^^^^^^ ^' Bereghszasz, ^d Mus! r«v t^ In. • • T^^ ^^^ '"^ ^ ^^"^ substance, partly characterized bv numerous luTrL'. *^r- '"^ "^""7 crystallizations of alum-st^ne or basic alum. The ^^^ lumps contam more or fewer flints disseminated through them, and ar;, accordS^S !(< 5S ALUM. ALUM. 0t I I" their auaUty, either picked out to make alum, or are thrown away. The sorted piecej Srrols?^ or Seined, by which operation apparenUy the hydrate of alumma, associated ^tirthe sulphate of klmnina, loses its water, and, as burnt clay, loses its affi-tity for S^/ Ittcomes, therefore, free ; and during the subsequent exposure to the weather TcSiriMcrwo;^^^^^^^^^ dlfalcati'on in the product of alum. For this reas^nTe contact of the ignited stones with carbonaceous matter ought to be avoided The calcS ato-stones, piled in heaps from 2 to 3 feet high, are to be exposed to the weathe^rnd meanwh^ must be continually kept moist by sprmkhng them with water As the water combines with the almn the stones crumble down and fall rventrily?into a pasty mass, which must be lixiviated with warm water, and allowed to sltt?e in a large cistern. The clear supernatant liquor, being drawn off, must be evapomted, and then crystallized. A second crystallization finishes the Pro<=e^2i^«^ f"^' nlsh^ a marketable alum. Thus the Roman alum is made, which is covered with a %' 'lut^^XL'r^^ Schist.-The greater portion of the alum found in BrUishcommeS made from alum-slate and analogous minerak. This slate contains mnrp nrlf^ir^^^^ mixcd with coaly or bitumiuous matter, which is occasionally ZwaTt asTr^S Tem somewhat Combustible. ^^ ^^^^^^l^lXTe^^^^ bituminous wood, where the upper layers lie immediately under clay beds, they consisx o^the coaly substlnce render^ impure with clay and p>Tites. This triple mixture cLstLtSL essence of all good alum schists, and it operates spontaneously towards Se Suet on of sulphate of alumina. The coal ser^'es to make the texture open, and oXw the air and moisture to penetrate freely, and to change the sulphur and iron pre- s^nt into acid and oxyde. When these schists are exposed o a high temperature m Sntact^th dr, the pyrites loses one half of its sulphur, in the form of subl^ed Suror sulphurous acid, and becomes a black sulphuret of iron, which speedily aSs oxyger^^^^^ tosulphate of iron, or green vitriol. The brown coal schists ^S Smmonly some green vitriol crystals, spontaneously f. rmed m them. The ZTxe ofTon tmnXs Us acid to the clay, progressively, as the iron by the action ont air witn l^Te ek becomes peroxydized; whereby sulphate of alumL is produced. A portion of the green vitriol remains, however undecomposed, and r^c^t^e more as the^Tmay happen to be less of other salifiable bases present m ?he day slate. Should a little magnesia or lime be present, the vitriol gets more completely decomposed, and a portion of Epsom salt and gyi^um is produced. ?he manufactu?e of alum from almn schLsts may be distributed under the sjx foUo^g heads —1 The preparation of the alum slate. 2. The hxiviation of the slate. 3. The evapomtio;"^^^^^^^^^ 4. The addition of the.saline ingredients or the pre- cipitation of the alum. 5. The washing of the almnmous salts ; and, 6. The crys^ "^f "" Priarahon of the Mum S/a/e.-Some alum slates are of such a nature that, being S in h^ps in the open air, and moistened from time to time they get spon- toieouslv ho? and by degrees foil into a pulverulent mass, ready to be lixiviated. The SeX part however, require the process of ustulation, from which they derive many ^vantages ' TlTe coVesiol of the dense slates is thereby so much impaired that their de- JornosS becomes more rapid; the decomposition of the pyrites is quickened by the T^^TorTZ?t^nof the sulphur; and the ready-formed green vitriol is parti, deLmTosed by the heat, with a transference of its sulphuric acid to the clay, and ^-"lu^ch^-L^f^^^^^^^^^^^ bitumen or coal for the roasting process must be interstratlfied with layers of smaU coal or brushwood over an extensive^^^^^^^^^ ^t Whitby the alum rock, broken into small pieces, is laid upon a ^onzontal bed ot lael, romposed of brushwood; but at Hurlett small coal is chiefly used fo^tbe lower bed When about four feet of the rock is piled on, fire is set to the bottom in various part^, and whenever the mass is fairly kindled, more rock is placed over the top. At Wh uny mis piling process is continued till the calcining heap is raised to the height of 90 or 100 feet The horizontal area is also augmented at the same time till it forms a great bed nearly 200 feet square, having therefore about 100,000 yards of solid measurement. Ihe ra- pidity of the combusti^on is tempered by plastering up the crevices ^^th sma^l schist ^oisLned. When such an immense mass is inflamed the heat is sure to rise too h^gh and an immense waste of sulphur and sulphuric acid must ensue. This ev I has been nSficed auTwhitby works. At Hurlett the height to which the heap is piled is only Tfew feet, while the horizontal area is expanded; which is a much more judicmus ar- rangement. At Whitby 130 tons of calcined schist produce on an average 1 ton of alum. In this humid climate it would be advisable to pile up on the top of the horizontal strata of brushwood or coal, and schist, a pyramidal mass of schist, which having its surface plastered smooth, with only a few air-holes, will protect the mass from the rains, and at the same time prevent the combustion from becoming too vehement. Should heavy rams supervene, a gutter must be scooped out round the pile for receiving the aluminous lixi- vium, and conducting it into the reservoir. It may be observed, that certain alum schists contain abundance of combustible matter, to keep up a suitable calcining heat after the fire is once kindled; and therefore nothing is needed but the first layer of brushwood, which, in this case, may be laid over the first bed of the bituminous schist. A continual, but very slow heat, with a smothered fire, is most beneficial for the ustulation of alum slate. When the fire is too brisk, the sulphuret of iron may run with the earthy matters into a species of slag, or the sulphur will be dissipated in vapor, by both of which accidents the product of alum will be impaired. Those bituminous alum schists which have been used as fuel under steam boilers have suffered such a violent combustion that their ashes yield almost no alum. Even the best regulated calciaing piles are apt to burn too briskly in high winds, and should have their draught- holes carefully stopped under such circumstances. It may be laid down as a general rule, that the slower the combustion the richer the roasted ore will be in sulphate of alumina. When the calcination is complete, the heap diminishes to one half its original bulk ; it is covered with a light reddish ash, and is open and porous in the interior, so that the air can circulate freely throughout the mass. To favor this access of air, the masses should not be too lofty ; and in dry weather a little water should be occasionally sprinkled on them, which, by dissolving away some of the saline matter, will make the interior more open to the atmosphere. When the calcined mineral becomes thoroughly cold, we may proceed to the lixiviation. But as, from the first construction of the piles or beds till their complete calcination, many weeks, or even months, may elapse, care ought to be taken to provide a sufficient number or extent of them, so as to have an adequate supply of material for carrying on the lixiviating and crystallizing processes during the course of the year, or at least during the severity of the winter season, when the calcination may be suspended, and the lixiviation becomes unsatisfactory. The beds are known to be sufficiently decomposed by the efflorescence of the salt which appears upon the stones, from the strong aluminous taste of the ashes, and from the appropriate chemical test of lixiviating an aliquot average portion of the mass, and seeing how much alum it will yield to solution of muriate or sulphate of fKitash. 2. The Lixiviation. — ^The lixiviation is best performed in stone-built cisterns ; those ol wood, however strong at first, are soon decomposed, and need repairs. They ought to be erected in the neighborhood of the calcining heaps, to save the labor of transport, and so ar- ranged that the solutions from the higher cisterns may spontaneously flow into the lower. In this point of view, a sloping terrace is the best situation for an alum work. In the lowest part of this terrace, and in the neighborhood of the boiling-house, there ought to be two or more large deep tanks, for holding the crude lixivium, and they should be protected from the rain by a proper shed. Upon a somewhat hisher level the cisterns of the clear lixivium may be placed. Into the highest range of cisterns the calcined mineral is to be put, taking care to lay the largest lumps at the bottom, and to cover them with lighter ashes. A sufficient quantity of water is now to be run over it, and allowed to rest for some time. The lixivium may then be drawn off, by a stopcock connected with a pipe at the bottom of the cistern, and run into another cistern at a somewhat lower level. Fresh water must now be poured on the partly exhausted schist, and allowed to remain for a sufficient time. This lixivium, being weak, should be run off into a separate tank. In some cases a third addition of fresh water may be requisite, and the weak lixivium which is drawn off may be reserved for a fresh portion ot calcined mineral. In order to save evaporation, it is always requisite to strengthen weak leys by employing them instead of water for fresh portions of calcined schist. Upon the ingenious disposition and form of these lixiviating cisterns much of the economy and sac- cess of an alum work depend. The hydrometer should be always used to determine the degree of concentration which the solutions acquire. The lixiviated stone, being thus exhausted of its soluble ingredients, is to be removed from the cisterns, and piled up in a heap in any convenient place, where it may be left either spontaneously to decompose, or, after drying, mav be subjected to another calci- nation. The density of the solution may be brought, upon an average, up to the sp. gr. of from 1-09 to M5. The lat'.er density may always be obtained by pumping up the weak- cr solutions upon fresh calcined mine. This strong liquor is then drawn off, when the sulphate of lime, the oxyde of iron, and the earths are deposited. It is of advantage to leave the liquor exposed for some time, whereby the green vitriol may pass into a per- I 1 ir 1 f 64 ALUM. sulphate of iron with the deposition of §ome oxyde, while the liberated acid may combine with some of the clay present, so as to increase the quantity of sulphate of alumina. The manufacture of alum is the more imperfect, as the quantity of sulphate of iron left tindecomposed is greater, and therefore every expedient ought to be tried to convert the sulphate of iron into sulphate of alumina. 3. The evaporation of the Schist Lixivium. — As the aluminous liquors, however well settled at first, are apt, on the great scale, to deposite earthy matters in the course of their concentration by heat, they are best evaporated by a surface fire, such as that employed at Hurlett and Campsie. A water-tight stone cistern must be built, having a layer of well rammed clay behind the flags or tiles which line its bottom and sides. This cistern may be 4 or 6 feet wide, 2 or 3 feet deep, and 30 or 40 feet long, and it is covered in by an arch of stone or brickwork. At one extremity of this tunnel, or covered canal, a fire-grate is set, and at the other a lofty chimney is erecied. The cistern being filled to the brim with the alum ley, a strong fire is kindled in the reverberatory grate, and the flame and hot air are forced to sweep along the surface of the liquor, so as to keep it in constant ebullition, and to carry off* the aqueous parts in vapor. The soot which is condensed in the process falls to the bottom, and leaves the body of the liquor clear. As the concentration goes on, more of the rough lixivium is run in from the settling cistern, placed on a somewhat higher level, till the whole gets charged with a clear liquor of a specific gravity sufficiently high for trans- ferring into the proper lead boilers. At Whitby, the lead pans are 10 feet long, 4 feet 9 inches wide, 2 feet 2 inches deep at the one end, and 2 feet 8 inches deep at the other. This increase of depth and cor- responding slope facilitates the decantation of the concentrated lixivium by means of a syphon, applied at the lower end. The bottom of the pan is supported by a series of parallel iron bars, placed very near each other. In these lead pans the liquor is concen- trated, at a brisk boiling heat, by means of the flame of a flue beneath them. Every morning the pans are emptied into a settling cistern of stone or lead. The specific gra- vity of the liquor should be about 1*4 or 1*5, being a saturated solution of the saline mat- ters present. The proper degree of density must vary, however, with different kinds of lixivia, and according to the different views of the manufacturer. For a liquor which consists of two parts of sulphate of alumma, and one part of sulphate of iron, a specific gravity of 1*25 may be sufficient ; but for a solution which contains two parts of sulphate of iron to one of sulphate of alumina, so that the green vitriol must be withdrawn first of all by crystallization, a specific gravity of 1*4 may be requisite. The construction of an evaporating furnace well adapted to the concentration of alu- minous and other crude lixivia, is described under Soda. The liquor basin may be made of tiles or flags puddled in clay, and secured at the seams with a good hydraulic cement. A mortar made of quicklime mixed with the exhausted schist in powder, and iron turn- ings, is said to answer well for this purpose. Sometimes over the reverberatory furnace a flat pan is laid, instead of the arched top, into which the crude liquor is put for neu- tralization and partial concentration. In Germany, such a pan is made of copper, because iron would waste too fast, and lead would be apt to melt. From this preparation basin the under evaporating trough is gradually supplied with hot liquor. At one side of this lower trough there is sometimes a door, through which the sediment may be raked out as it accumulates upon the bottom. Such a contrivance is convenient for this mode of evaporation, and it permits, also, any repairs to be readily made ; but, indeed, an appa* ratus of this kind, well mounted at first, will serve for many years. In the course of the final concentration of the liquors, it is customary to add some of the mother waters of a former process, the quantity of which must be regulated by a proper analysis and knowledge of their contents. If these mother waters contain much free sulphuric acid, from the peroxydation of their sulphate of iron, they may prove useful in dissolving a portion of the alumina of the sediment which is always present in greatei or less quantity. 4. The precipitation of the Mum by adding ^Alkaline Salts. — As a general rule, it is most advantageous to separate, first of ail, from the concentrated clear liquors, the alum in the state of powder or small crystals, by addition of the proper alkaline matter, and to leave the mingled foreign salts, such as the sulphate of iron or magnesia, in solution, instead of trying to abstract these salts by a previous crystallization. In this way we not only simplify and accelerate the manufacture of alum, and leave the mother waters to be worked up at any convenient season, but we also avoid the risk of withdrawing any of the sulphate of alumina with the sulphate of iron or magnesia. On this account, the concentration of the liquor ought not to be pushed so far as that, when it gets cold, it should throw out crj'stals, but merely to the verge of this point. This density may be determined by suitable experiments. The clear liquor should now be run oflf into the precipitation cistern, and have the ALUM. 6S proper quantity of sulphate or muriate of potash, or impure sulphate or carbonate of ammonia added to it. The sulphate of potash, which is the best precipitant, forms 18-34 parts out of 100 of crystallized alum; and therefore that quantity of it, or its equivalent in muriate of potash, or other potash or ammoniacal salts, must be introduced into the aluminous liquor. Since sulphate of potash takes 10 parts of cold water to dissolve it, but is much more soluble in boiling water, and since the precipitation of alum is more abundant the more concentrated the mingled solutions are, it would be prudent to add the suIphAte solution as hot as may be convenient ; but, as muriate of potash is fully three times more soluble in cold water, it is to be preferred as a precipitant, when it can be procured at a cheap rate. It has, also, the advantage of decomposing the sulphate of iron present into a muriate, a salt very difficult of crystallization, and, therefore, less apt to contaminate the crystals of alum. The quantity of alkaline salts requisite to precipitate the alum, in a granular powder, from the lixivium, depends on their rich- ness in potash or ammonia, on the one hand, and on the richness of the liquors in sulphate of alumina on the other ; and it must be ascertained, for each large quantity of product, by a preliminary experiment in a precipitation glass. Here, an aliquot measure of the aluminous liquor being taken, the liquid precipitant must be added in successive portions, as long as it causes any cloud, when the quantity added will be indicated by the graduation of the vessel. A very exact approximation is not practicable upon the great scale ; but, as the mother waters are afterwards mixed together in one cistern, any excess of the precipitant, at one time, is corrected by excess of aluminous siilphate at another, and the resulting alum meal is collected at the bottom. When the precipitat- ed saline powder is thoroughly settled and cooled, the supernatant mother water must be drawn off by a pump, or rather a syphon or stopcock, into a lower cistern. The more completely this drainage is cflTected, the more easily and completely will the alum be purified. This mother liquor has, generally, a specific ffravity of 1-4 at a medium temperature of the atmosphere, and consists of a satarated solution of sulphate or muriate of black and red oxyde of iron, with sulphate of magnesia, in certain localities, and muriate of soda, when the soaper's salt has been used as a precipitant, as also a saturated solution of sulphate of alumina. By adding some of it, from time to time, to the fresh lixivia, a portion of that sulphate is converted into alum ; but, eventually, the mother water must be evaporated, so as to obtain from it a crop of ferruginous crystals; after which it be- comes capable, once more, of giving up its alum to the alkaline precipiianLs. When the aluminous lixivia contain a great deal of sulphate of iron, it may be good poUcy to withdraw a portion of it by crystallization before precipitating the alum. With this view, the liquors must be evaporated to the density of 1-4, and then run oflf into crj'staiJizmg stone cisterns. After the green vitriol has concreted, the liquor should be pumped back mto the evaporating pan, and again brought to the density of 1'.4. On aaamg to it, now, the alkaline precipitants, the alum will fall down from this concentrat- ed solution, m a very minute crystalline powder, very easy to wash and purify. But this method requires more vessels and manipulation than the preceding, and should only be fKo Jrr^w ^ ? necessity; since it compels us to carry on the^ manufacture of both PT?rI^P f^^""' ['""^ '^^ admixture of the ferriginous liquors; but IrLe s^xteenfhTr'-. ^^ "^^^^^^f T^^ ^"^ *=°^^ Water, which dissolves not more weU together thif^^ weight of alum. After stirring the powder and the water Tawn off A ..InT' ""il-'' ^' f °^^^ ^"^ '^"^^' ^"^ ^hen the washing must be ill^ iA T""^^ washing will render the alum nearly pure. The less water pro^S ^^Tie\"i '\' T' *^^^J^"^^y '' ^' ^^'^^^ «ff» the' mor; complete « Se •l^^wd^r in r X nf""^^ ^ r"^ Sv'^" ^'' ^^«hi"g «f *"other portion of . iixiWa. ^ ^'""^ ^*^^'* ^^^'^ washings may be added to the schist watr^t'dT^nlvi^'^^'i'^TT^^ washed alum is put into a lead pan, with just enough ^iSni Whin ^■^' ^^"? ^T^ • ^'^ '^ *PP"^^> '^"d the solution is pron.oted by SfwhTch arTn^n J ^T^^"^ 'V ^ '"i"'^'^ «^^^^' '' ^« "t*^ ofl" into the Crystallizing wwTin tip mJHHi ^ 'T^'""^ '^'^'- ^^^'^ '^^^'^s ^'•e ab«"t five feet high, three feet niSy fitted^ eichTh'''^^^"^^^^^^^ V^' ^""^^ ' they are made of very strong staves, ^Lv^ lo Z^t^ ' """1^^^^ ^?^f^^' ^y ^*'"°'^? i^°» hoops, which are driven on JI^S The It ^^ f?^ ^ -^'^i ^"^'^^^ ^ff ^^*>»' i» «^e' to take the staves Targe reiullrci^s^^^^^^ ^ts slow cooling in these close vessels, forms aXrLver or cSir..'f^^ hang down from the top, and project from the sides/ while « imck layer or cake lines the whole mterior of the cask. At the end of eight or ten days li 'V I f'. •' 56 ALUM. more or less, acccording to the weather, the hoops and staves are removed, when a cask, of apparently solid alum is disclosed to view. The workman now pierces this mass with a pickaxe at the side near the bottom, and allows the mother water of the interior to run off on the sloping stone floor into a proper cistern, whence it is taken and added to another quantity of washed powder to be crystallized with it. The alum is next broken into lumps, "exposed in a proper place to dry, and is then put into the finished bing for the market. There is sometimes a little insoluble basic alum (subsulphate) left at the bottom of the cask. This being mixed with the former mother liquors, gets sulphuric acid from them ; or, being mixed with a little sulphuric acid, it is equally converted into alum. When, instead of potash or its salts, the amrooniacal salts are used, or putrid urine, with the aluminous lixivia, ammoniacal alum is produced, which is perfectly similar to the potash alum in its appearance and properties. At a gentle heat both lose their wa- ter of crystallization, amounting to 45^ per cent, for the potash alum, and 48 for the am- moniacal. The quantity of acid is the same in both, as, also, very nearly the quantity ot alumina, as the following analyses will show : — Potash alum. Sulphate of potash Sulphate of alumina Water - - - 18-34 36-20 45-46 100-00 Ammonia alum. Sulphate of ammonia Sulphate of alumina Water - - - - Or otherwise. Potash alum. 1 atom sulphate of potash - 1089-07 1 alumina - 2149-80 24 water ... - 2669-52 Ammonia alum. 1 atom sulphate of ammonia 1 alumina 24 water - - - - 6938-39 12-88 38-64 48-48 100-00 716-7 2149-8 2699-5 5566-0 Or, Potash alum. Ammonia alum. Alumina - - - . 10-82 Alumina - - - - 11-90 Potash ... - 9-94 Ammonia - - - - 3-89 Sulphuric acid - - - 33-77 Sulphuric acid - 36-10 Water 45-47 Water - - - - - 48-11 100-00 100-00 Wlien heated pretty strongly, the ammoniacal alum loses its sulphuric acid and ammonia, and only the earth remains. This is a very convenient process for procuring pure alumina. Ammoniacal alum is easily distinguished from the other by the smell of ammonia which it exhales when triturated with quicklime. The Roman aluin, made from alum-stone, possesses most of the properties of the schist-made alums, bui it has a few peculiar characters : it crystallizes always in opaque cubes, whereas the common alum crystallizes in transparent octahedrons. It is probable that Roman alum is a sulphate of alumina and potash, with a slight excess of the earthly ingredient. It is permanent when dissolved in cold water ; for after a slow evaporation it is recovered in d cubical form. But when it is dissolved in water heated to 110* Fahr. and upwards, oi when its solution is heated above this pitch, subsulphate of alumina falls, and on evaporation octahedral crystals of common alum are obtained. The exact composition of the Roman alum has not been determined, as far as I know. It probably differs ft om the other also in its water of crystallization. The Roman alum contains, according to MM. Thenard and Roard, only ^Jqq of sulphate of iron, while the common commercial alums contain roo'o- ^^ ^^^ ^^ easily purified by solution, granulation, crystallization, and washing, as has been already explained. Alum is made extensively in France from an artificial sulphate of alumina. For thL§ purpose clays are chosen as free as possible from carbonate of lime and oxyde of iron. They are calcined in a reverberatory furnace, in order to expel the water, to peroxydizc the iron, and to render the alumina more easily acted on by the acid. The expulsion of the water renders the clay porous and capable of absorbing the sulphuric acid by capillary attraction. The peroxydation of the iron renders it less soluble in the TOlphuric acid; and the siljca of the clay, by reacting on the .ilumina, impairs its aggregation, and makes it more readily attracted by the acid. The clay shoiild, therefore, ALUM. 57 be moderately calcined ; but not so as to indurate it like pottery ware, for it would then Ufler a species of silicious combination which would make it resist the action of acids. The clay is usually calcined in a reverberatory furnace, the flame of which serves thereafter to heat two evaporating pans and a basin for containing a mixture of the calcined clay and sulphuric acid. As soon as the clay has become friable in the furnace it is taken out, reduced to powder, and passed through a fine sieve. With 100 parts of the pulverized clay, 45 parts of sulphuric acid, of sp. gr. 1-45, are well mixed, in a stone basin, arched over with brickwork. The flame and hot air of a reverberatory furnace are made to play along the mixture, in the same way as described for evaporating the schist liquors. See Soda. The mixture, being stirred from time to time, is, at the end of a few days, to be raked out, and to be set aside in a warm place, for the acid \o work on the clay, during six or eight weeks. At the end of this time it must be washed, to extract the sulphate of alumina. W^ith this view, it may be treated like the roasted alum ores above described. If potash alum is to be formed, this sulphate of alumina is evaporated to the specific gravity of 1-38; but if ammonia alum, to the specific gravity of only 1*24; because the sulphate of ammonia, being soluble in twice its weight of water, will cause a precipitation of pulverulent alum from a weaker solution of sulphate of alumina than the less soluble sulphate of potash could do. The alum stone, from which the Roman alum is made, contains potash. The following analysis of alunite, by M. Cordier, places this fact in a clear light : — Sulphate of potasn Sulphate of alumina Hydrate of alumina 18-53 38-50 42-97 100-00 To transform this compound into alum, it is merely necessary to abstract the hydrate of alumina. The ordinary alum stone, however, is rarely so pure as the above analysis would seem to show ; for it contains a mixture of other substances ; and the above are in diflierent proportions. Alum is very extensively employed in the arts, most particularly in dyeing, lake making, dressing sheep-skins, pasting paper, in clarifying liquors, &,c. Its purity for the dyer may be tested by prussiate of potash, which will give solution of alum a blue tint in a few minutes if it contain even a very minute portion of iron. A bit of nut-gall is also a good test of iron. Altuu liquors. — In the alum, works on the Yorkshire coast, 8 different liquore arc met with. 1st " Raw Liquor." The calcined alum shale is steeped in water till the liquor has acquired a specific gravity of 9 or 10 pennyweights, according to the lan- guage of the alum-maker. 2d. " Clarified Liquor." The raw liquor is brought to the boiling point in lead jians, and suffered to stand in a cistern till it has cleared: it is then called clari- fied liquor. Its gravity is raised to 10 or 11 pennyweights. 3d. " Concentiated Liquor." Clarified liquor is boiled down to about 20 penny- weights. This is kept merely as a test of the comparative value of the potash salts used by the alum-maker. 4th. " Alum Mother Liquor." The alum pans are fed with clarified liquor, which is boiled down to about 25 or 30 pennyweights, when a proper quantity of potash salt in solution is mixed with it, and the whole run into coolers to crystallize. The liquor pumped from those rough crystals is called " alum mothers." 6th. "Salts Mothers." and afford a crop toxide of iron. 6th and 7th. "Alum Washings." The rough crystals of Alum (Xo. 4) are washed twice in water, the first washing being atout 4 pennyweights, the second about 2i, the difference in gravity being due to mother I'iquor clinging to the crystals. 8th. "Tun Liquor." The washed crystals are now dissolved in boiling water, and run into the "roehing tuns" (wood vessels lined with lead) to cry^^tallize. The mother liquor of the "roch alum" is called "tun liquor;" it is, of course, not qujte so pure as a solution of roch alum in water. The alum-maker's sp. gr. bottle holds 80 pennyweights of water, and by 10 penny- weights he means 10 more than water, or 90. -i r j The numbers on Twaddle's hydrometer, divided by 2-6, give alum-makers' penny- '." The alum mothers are boiled down to a crystallizing point, of " Rough Epsom," which is a sulphate of magnesia and pro- lill '■\V 11 \\ ' i M I 68 ALUM. The alum-maker tests his samples of potash salts comparatively by dissolving equal weights of the different samples in equal measures of alum liquor at 20 pennyweights, heated up to the boiling-point, and weighing the quantity of alum crystals produced on cooling. For the above information I am indebted to my friend, Mr. Maurice Scanlan, who superintended for some time the Mulgrave alum works. He informs me that 61 1 tons of the alum rock at the Mulgrave Works, to the north of Whitby, yield, after calcination, 66 ANCHOR. ANCHOR. m III ness at the extremities. In small anchors the stock is frequently "^f^f/f/^" ' J'";L*^ this case it does not embrace the anchor, but goes through a hole made m the square, which is swelled out on purpose. _♦• i f^ ti,*. t^nnntrp • n frond rule The weight of anchors for different vessels is proportioned to the ^^^"J^^f^^ '^^.^^^/^^ bein^ to mSke the anchor in hundred weights one twentieth of the "«?l^^/ ?[ ^^^^^JT ^ burden. Thus a ship of 1000 tons would require a sheet anchor of 50 cwts. Ships of war are provided with somewhat heavier anchors. Piner's na- Several new forms and constructions of anchors were proposed under Mr. l;»P«y s pa tent of November, 1822, by the adoption of which great advantages as to sUengUi were anticipated over every other form or construction previously made The particular object was to preserve such a disposition of the fibres of the melaJ as shoiSd aS the greatest possible strength; in doing which the crossing or bend mj of the fibres at the junctions of the shank, fiukes, and crown, where great streng h ^ re- quirXh^^ been avoided as much as possible, so that the fibres are not disturbed or ^Kis respect most anchors are defective ; for in connecting the shanks to the crown- pieces, the gkin of the metal is either crossed, or so much curv'ed, as to stram the fibre, and consequently induce a weakness where the greatest strength is req^red And [or- ther, the very considerable thicknesses of metal which are to be brought ^^^^^^'f^ contact by means of the hammer in forging anchors upon the old <^«"^^;;»«;; ^^^^^^^^^ highly probable that faulty places may be left ^vithm the mass, though they be exteni^ Siperceptible. Mr. PipeJ's leading principle was, that the fibre of the metal should run nearly straight in aU the parts where strength is particularly required. ^- ^ J-tV. 15 shows an anchor with one tumbling fluke, wl»cB passes through the forked or branched part of the shank. 1^ lower part of this anchor, answering to the crown, has a spin- dle through it, upon which the fluke turns, and a pm is there Tntroduc^ for the purpose of confining the fl«ke wto m « holding position. This shank is formed of a sobd piece of wrought iron, the fibres of which run straight, and at the Trown holes are pierced, which merely bulge the ^etal wUhout bendin- the fibres round so as to strain them. The arm and Suke' also, are formed of one piece punched through ^vithout —^ ^ curliAg or crossing the fibre, and the spindle which holds the • 1-1 • ♦J^;„i,t "Thic Qnindle extends some distance on each side arm to the crown is likewise straight. 1 hLS spmaie exxeims »« that side which is nearest the ground, and wiU there be ready to take hold when me anchor is drawn forward. .^ ^^^^^^^ ^^^^^^ ^^^ r^./Tt^\^i sU-htlf varied in form from the last. In this the forked part of Uie shank is closer than in the former, and there are two arms or flukes connected to the crown^pieces, of «f ^]^^1,;;^^^ into its holding position as the anchor comes to the ground and is held at its proper angle by the other fluke stoppmg '^^F?g.M6%t;res;nts another variation m the form of these improved anchors, having two tumbling flukes, which are ^A intended to take hold of the ground at the same t"ne The diank is here, as before, made without crossing j^e gram of the --, and^the^e^e^ for admitting the bolt at the crown and at *^%s^%^^.,^%P^^^^^°^ i^ introduced at "■^r n'tas^'a shank without any fork, but formed ^raight t''™»S»'°f .; »'-,f "i;^, ^iX^i'irtoihrs;!^^^^^^^^^ made of straight lengths otmeta^^^^^^ ^^ ^^^ .^ ^^^^ injured by c^^os^-f l^*,'^^'.^'^'^^^ Unes so that the fibres will not be altered, and the solid piece, and finished insraightM ^^^ .^ ^^^ iniprovement ^cSr Ve^set\^o^s,S^gmad'^^ a great advantage to the 67 =1I=3P workman to execute each part perfectly ; for he will not have such heavy weights to lift when hot, which will render these anchors much stronger, with less weight ; and if any accident should happen to them, any part may be taken separate from the others to be repaired, and several of those parts of the anchor which may be likely to break may be carried on board, in case of accident. This anchor is so contrived that one of thirty hundred weight may be taken to pieces and put together again, by one man, in twenty minutes ; it may also be dismounted, and stowed in any part of the ship, in as little room as straight^rs of iron, and speedily put together again. The anchor (Jig. 18) patented by Mr. Brunton, in February, 1822, has its stock introduced at the crown part, for the purpose of turning it over into a holding position. The shanlc is perfora- ted through the solid, in two places, with elliptical apertures, for the purpose of giving it a greater stability, and more efleclually resisting the strain to which the anchor may be subjected. The stock is a cylindrical iron rod, held at its extremities by lateral braces, which are bolted to the shank. ^ f'^S- 18 shows the form of the anchor. The shank is seen upright, with one of the flukes projecting in its front; the horizontal iron stock is at bottom ; and the oblique braces are bolted to both shank and stock. The ends of the stock, from the shouId«^, are formed dove-tailed, and oval in the vertical direction, and are protruded through apertures in the bra- ces, also oval, but in the horizontal direction, and counter sunk. When the ends of the stock have been thus introduced through the holes, the braces are securely bolted to the shank, the ends of the stock are then spread, by hammering into the counter-sunk holes of the braces, and by that means they are made firm. An anchor of this description is consider- ed by the patentee to possess considerable advantage, particularly in point of stability, over the ordinary construction of anchors, and is economical, inasmuch as a less weight of metal will give, upon this plan, an equal degree of strength. An ingenious form of anchor was made the subject of a patent, by Lieutenant Rodg- ers, of the Royal NavT, in 1828, and was afterwards modified by him in a second pa- tent, obtained in August, 1829. The whole of the parts of the anchor are to be bound together by means of iron bands or hoops, in place of bolts or pins. Fig, 19 is a side view of a complete anchor, formed upon his last improved construction, and Jig. 20, a plan of the same; fig. 21, an end view of the crown and flukes, or arms; Jig. 22 represents the two principal iron plates, a, a, of which the shank is constructed, but so as to form parts of the stump arms to which the flukes are to be connected. Pi® 7°^ ^^^^^ ^ ^ ^^ "^^^^^ ^o the stump piece, c, c. Jig. 22, as well as to the end I of the centre piece h A, and the scarfs m m are to be cut 'to receive the arms or flukes. Previously, however, to uniting the arms or flukes with the stump arms, the crown and throat of the anchor are to be strengthened, by the application of the crown slabs « Ti,/tg. 22, which are to be welded upon each side of the crown, overlapping the end of the pillar /i, and the throat or knees of the stump arms and the crown piece. The slump arms are then to be strengthened in a similar manner, by the thin flat pieces p p which are to be welded upon each side. The palms are united to the flukes in the usual way and the flukes are also united to the stump arms by means of the long scarfs m m. When the shank of the anchor has been thus formed, and united with the flukes, the anchor smith's work may be said to be complete. Another of the improvements in the construction of anchors, claimed under this patent, consists m a new method of affixing the stock upon the shank of the anchor, rncw!'.n^l'^o. '^. the following manner : in Jig. 20, the stock is shown affixed to the anchor, m^g. 23 it is shown detached. It may be made either of one or two pieces dita IIM i n ii ', W t ' I 68 AimEALING. of timber, as may be found most convenient. It is, however, to be observed, that the stock is to be completed before fitting on to the shank. After the stock is shaped, a hole is to be made through the middle of it, to fit that part of the shank to which it is to be aflixed. Two stock plates are then to be let in, one on each side of the stock, and made fast by counter sunk nails and straps, or hoops ; other straps or hoops of iron are also to be placed round the stock, as usual. In place of nuts, formed upon the shank of the anchor, it is proposed to secure the stock by means of a hoop and a key, shown above and below j, mjig. 20. By thia contrivance, the stock is prevented from going nearer to the crown of the anchor than it ought to do, and the key prevents it from sliding towards the shackle. Since fitting the stock to the shank of an anchor, by this method, prevents the use of a ring, as in the ordinary manner, the patentee says that he in all cases substitutes a shackle for the ring, and which is all that is required for a chain cable ; but, when a hempen cable is to be used, he connects a ring to the usual shackle, by means of a joining shackle, as in Jigs. 19 and 20. Mr. Rodgers proposes under another patent, dated July, 1833, to alter the size and form of the palms ; having found from experience that anchors with small palms will not only hold better than with large ones, but that the arms of the anchor, even with out any palms> have been found to take more secure hold of the ground than anchoi*8 of the old construction, of similar weight and length. He has, accordingly, fixed upon one-fifth of the length of the arm, as a suitable proportion for the Ungth or depth of the palm. He makes the palms, also, broader than they are long or deep. ANILINE. An organic compound, which may be procured in several ways : 1, •when isatine (see Indigo) is fused with solid hydrate of potash ; 2, when to an alcoholic solution of benzine a little zinc and muriatic acid is added : but it is obtained best from coal tar, which is to be distilled in a large iron retort, and the successive products to be separately received, especially the latter and denser ones. This heavy tar-oil is to be strongly agitated along with muriatic acid in a glass globe. The acid solution contains the aniline, which, being of an alkaline nature, is called a volatile base. It must be subjected to an operose process of purification, with milk of lime, ^'^ '' ^''^^ ^ ^^^^ 1*>'^^ «f g«o°L«f^X^^7«"^f^ are set up a-ainst each other, which is called ridg.ng or bonting. The land, then, is entire ylaid'in ridges and deep furrows, by which it is more exposed to the influence of the atmosphere and kept drier. This is generally done before winter, especially in stiff wet soils Sometimes two or more ridges are made on each side forming narrow stitches When the ground is to be ploughed without bemg laid in ands or st tches, and all the ridges inclined one way, the mould board of the plough is shifted at each turn from one side to the other. The plough which admits of this is called a turn^est SoLTand is in general use in Kent and in many parts of the Continent, where the Sil is dry and the land not too moist. In most other situations the ground is laid n"and^the mould board of the plough is fixed on the right side When grass and or stubble is ploughed, care must be taken to bury the gross and weeds com- pletely; and the slice cut off by the plough must be turned fjer entirely which is best done by making the width of the furrow greater than the depth. When the gr^s and we^eds are rotten, and the ground is ploughed to pulverize it, ^ n^-^ <^eeP furrow is best. The earth ploughed up is laid against the side of the preceding ridge whiclTforms a small furrow between the tops of the ridges, well adapted for the seed to lodge in, and to be readily covered with the harrows. , , Nothin- has divided both practical and theoretical agriculturists more than the question whether the land should be ploughed deep or shallow ; but a very slight at- tention to the purposes for which land is ploughed, and to the nature of the soi^ wi readily reconcile these apparently contradictory opinions. A deep, rich, and stiff soil can ne^ver be moved too much nor too deep. Deep ploughing brings up rich earth admits the air and water readily, and gives room for the roots to shoot, while the rich cXact soil affords moisture and nourishment. Wherever trees are to be plante<^ thrground should be stirred as deep as possible, even in a p •''''"'•^'/r"' ^ ?^ y"^} ^^^y' ^^ ^^" P^^^^^ ^^^ «««dy ; and the chances ZXl^W ''.^\'^^^^^ '? ^''^ judgment, and finds it out when he has already em- bailed his capital in a losing concern. Next to the nature of the soil is to be consid- flfJnn nf .r^'^'^K M^-^^'''? ""L^^^ ^^^°^' ^^'^ disposition of the ficlds, and the adap- tation of the farm-buildings to the most profitable occupation of the land. The roads tX7 1 . '' 7-'''^ !'"? \'' '^' neighboring towns, whence manure may be ot Jhiv^ ^^%*^°io«t important object, and if there is water carriage, it greatly Inhanees vard th?onnv ^•'°'- ?i' '""-^^ '^ '^^ *^"^^^ '""^ '^^ ^i««^«°«^ of these from the W ^thlhnrt^J T'^'T^ of having good pasture, or land easily laid down to grass, near land Zd fh^V /'P'''?"^ ?' ''*"^*^^" «^ ^^' farm-buifdings with respect to tS sfde;.d tnS wt''? 'tr^^''^"^ ''^^^''i ^"" "" circumstances which must £ well con- whirhVav bl flinlX L^^^ probable profits, and consequently the rent for th. T.rl I -u • ^ ^^ .1^ :?-^"^''?^ situation is no doubt the most advantageous manure Rnth^^' *' ^^^-^ diminishing the labor in harvest, and in carrying oS m?ty of'th?i«n? "^^.be ci^^^-js ances which render some spot nearer the eltre- Trec^ted that tT. • ' T^'^^"' ^u^ '\}' ^^^^ ^^^^^ ^^^^^^ new buildings are to be tered situatinn! T V'^^'''''^' ?? ^^^ farm-buildings are generally in low and shell L the heavtrt thin '* f, ^''^\ inconvenience to have to carry tL manure, which ^raL sloprne thp^i^f h ? ^'^ \ ^"'™i' -"C * '^''^ ^'^^ ^1^^ best situation is on a mo- is^rp^rtn^^^^ i ! j 1 ; 1 * ! i II Mi 'i: i !' t k; ; ^1 76 AKABLE LAND. such as the farm requires. The rooms should be airy and healthy, facing the south, with a neat garden m front of the house. The farm-yard should be to the north, be- hind it Near the house, and the farm-yard, there should be a small paved court, separated from the j^ard by a low wall. In this court, which should communicate with the dairy, utensils may be placed on proper benches, to air and dry in the sun. The architecture of the buildings may be left to the taste of the proprietor ot his archi tect The simpler it is, the more appropriate. The yard or yards in a large farm should be sheltered on the north side by the barns, which need not be so extensive as used formerly to be thought necessary. If there is a thrashing machine, a single floor to thrash the seeds upon, and to employ the men occasionally in winter, is quite suf- ficient Every farm which is so extensive as to require more than one floor to thrash the corn on, ought always to have a thrashing mill attached to it A small yard, distinct from the other, with sheds for the cattle to shelter themselves under, in wet and stoi-my weather, is a great advantage, and may be added at a tri- fling expense to any set of farm-buildings. The cart-sheds should be in the stack-yard, which properly occupies a space north of the barn. There should be a sufficient number of stands, with proper pillars and frames to build stacks on. Each stack should be of such a size as to be conveniently taken into the barn to be thrashed out The round form, and the square which becomes nearly round when built up, are most convenient Nine stone or cast-iron pillars, with caps over them, are placed on brick foundations, and support a strong frame on which the stack is built In the centre of the stack there is usually a pyramidical open frame, to allow the air to circulate through the stack, and prevent the heating of the grain. On each side of the yard should be placed the stables, cow-houses, and feeding-stalls, with a pump of good water near the last, and convenient places to put ha}', straw, and turnips m, with a machine to cut them. A great deal of time and labor is saved by a proper arrange- ment of the different parts of the farm-buildings. An underground cistern near the cow-house and stables, into which the urine and washings of the cow-house may run by means of a sink or drain, is a most useful appendage, which is too little thought of in England, whereas it is one of the most indispensable parts of a Flemish farm. It supplies a kind of manure, which can be applied to the land at all times, which invig- orates sickly crops, and may often produce an abundant return, where otherwise there would be a complete failure. In Scotland it is notorious that rents are much higher than in England, not only for small occupations, but for extensive farms ; and that the tenants have complained less of the times than their neighbors in the south. It may be worth while to inquire into the cause of this, for the low price of corn must affect the Scotch farmer equally with the English. One great difference between the Scotch and the English farmer is, that the former gets work done at a cheaper rate than the latter. The Scotch laborer is fully as well fed, and clothed, and lodged, as the English ; but he has less money to spend at the ale-house. He is paid, not in a certain sum every Saturday, but in com- forts, in the keep of a cow, in a certain number of rows of potatoes, a certain quantity of malt to make his beer, a cottage to live in, and oatmeal to feed his family. His immediate wants are supplied, and he is comfortable ; the consequence is, that he works willingly. He has no remnant of the last night's debauch at the beer-shop. He is early at work, and he does his work cheerfully. The horses of a Scotch farmer are well fed; they are always in good condition. They work 10 and even 12 hours in a day, at 2 yokings. The ploughman only thinks how he shall finish his work in proper time, and unless he makes the horses work as much as they can without dis- tressing them, he knows he shall not get through his work. All this is worth 25 per cent on the whole labor of the farm, as Arthur Young has very judiciously calculated, when he gives the expense of labor on the farm of a gentleman, compared with that on the land of a farmer who works with his men. The moral effect of an interest in the work to be done, when opposed to that of a perfectly distinct and often hostile interest, will readily account for so great a difference. But besides this, the Scotch farmer has generally the advantage of a scientific edu- cation, and of a thorough knowledge of the principles of his profession ; and with the shrewdness peculiar to his country, he knows how to take advantage of every favor- able circumstance. He has also been taught to calculate, and will soon discover where there is a profit or a loss. This has made him turn his attention to cattle and sheep of late years, more than to the production of corn ; and the Scotch have found that while a very decent profit was made on the cattle, their land produced more corn, although it sold at a lower price; for the green crops raised for the cattle, and the manure made by them, enriched the land so much, that the average produce on some light lands was nearly doubled. All this kept up rents to a much higher level than in England, where prices were low, and there were no means of diminishing expenses or increasing produce. Hence rents in Scotland have kept up wonderfully, when w« consider the great fall of rents in England since the peace. ARCHIL. 77 ABCHIL. A violet red paste used in dyeing, of which the substance called cudbear in Scotland (from Cuthbert, it» first preparer in that form), is a modification. Two kinds of archil are distinguished in commerce, the archil plant of the Canaries, and that of Auvergne. The first is most esteemed: it is prepared from the lichen rocellusj which grows on rocks adjoining the sea in the Canary and Cape de Verd Islands, in Sar- dinia, Minorca, &c., as well as on the rocks of Sweden. The second species is prepared from the lichen parellus, which grows on the basaltic rocks of Auvergne. There are several other species of lichen which might be employed in producing an analogous dye, were they prepared, like the preceding, into the substance called archil. Hellot gives the following method for discovering if they possess this properly. A little of the plant is to be put into a glass vessel ; it is to be moistened with ammonia and lime-water in equal parts ; a little muriate of ammonia (sal ammoniac) is added ; and the small vessel is corked. If the plant be of a nature to afford a red dye, after three or four days, the small portion of liquid, which will run off on inclining the vessel, now opened, will be tinged of a crimson red, and the plant itself will have assumed this color. If the liquor or the plant does not take this color, nothing need be hoped for; and it is useless to attempt its preparation on the great scale. Lewis says, however, that he has tested in this way a great many mosses, and that most of them afforded him a yellow or reddish-brown color ; but that he obtained from only a small number a liquor of a deep red, which communicated to cloth merely a yeUowish-red color. Prepared archil gives out. its color very readily to water, ammonia, and alcohol. Its solution in alcohol is used for filling spirit-of-wine thermometers ; and when these ther- mometers are well freed from air, the liquor loses its color in some years, as Abbe Nollet observed. The contact of air restores the color, which is destroyed anew, in vacuo, in process of time. The watery infusion loses its color, by the privation of air, in a few days ; a singular phenomenon, which merits new researches. The infusion of archil is of a crimson bordering on violet. As it contains ammonia, which has akeady modified its natural color, the fixed alkalies can produce little change on it, only deepening the color a little, and making it more violet. Alum forms inlit a precipitate of a brown red; and the supernatant liquid retains a yellowish-red color. The solution of tin affords a reddish precipitate, which falls down slowly ; the super- natant liquid retains a feeble red color. The other metallic salts produce precipitates which offer nothing remarkable. The watery solution of archil, applied to cold marble, penetrates it, communicating a beautiful violet color, or a blue bordering on purple, which resists the air much longer than the archil colors applied to other substances. Dufay says, that he has seen marble tinned with this color preserve it without alteration at the end of two years. To dye with archil, the quantity of this substance deemed necessary, according to the quantity of wool or stuff to be dyed, and according to the shade to which they are to he brought, is to be diffused in a bath of water as soon as it begins to grow warm. The bath IS then healed till it be ready to boU, and the wool or stuff is passed through it without Tl «t^e':PrfParat.on, except keeping that longest in, which is to have the deepest shade. A hne gridehn, bordering upon violet, is thereby obtained ; but this color has no perma- afvo 1* . ?''?u^'*'^u '^ ""^^^y employed with any other view than to modifv, heighten, and give lustre to the other colors Hellot says, that having employed archifon wool h^^iled with tartar and alum, the color resisted the air no more than what had received no cZ-Tv wf • ^\''^v^'f ^ ^'°"' ?^'.^ ^'^^'^ (''*^^^^"« '^''^^^^) a «^"ch more durable ^nW **y P = ''' ^^^ ^^^^ "'^'"^ '°^''*'"" °^ *^"- '^^e a'-chil thereby loses its natural nf li.,t" ^f""."^^ one approaching more or less to scariet, according to the quantity a« thnt 7 '^^'iY'^T^^^y^: This process must be executed in nearly Ihe same mannS as that of scarlet, except that the dyeing may be performed in a single bath. I„Jt^. l"^ T-^"'^^^]'^^'"^^'''^^^^ for varying the different shades and giving them deetr tSne'L /o7the ^T ^^'''''' '"^''^'- °^^"^"^' '^^^ ^^^^^^^^^ A^^^^^- To obtain^ n>;t^MTif'-* S[ ■ ^eep soupes au mn, sometunes a little alkali or milk of lime is AJum Lnnnt bp T ^Z J^'"^ J^''"^' ^^ ^^*^^°^^ «« ^^^"^i^^ ^Y ^t^er processes it S'mmunt^t^^ V' T^"™,^^^ ^« the ^chU of Auvergne, from the greater bloom which has SShp tl !? ^^^ ^''^r'^ ^"^^ ^'^"^ ^^^ ^^'^^' ^"^ntity of coloring matter. It Jrith^um ' whi.h^'?''l^^' of bearing ebullition. The latter, moreover, dols not answer d?eL.n an !r' ^ f^^'"^' ^^^ '^^°' ' ^^^ *^« ^^'^ "^^^^ ^^^ ^^^ inconvenience of Sr^„^,onnnfT^" manner unless attention be given to pass the cloth through hot water as soon as it comes out of the dye. = *- s "*/v WL^^^.rniT \*1? ^^J^^ ^>'""^ '^» "n^e^s for lilachs; butsflk is frequently ff in n^r "i ^^^ rr"'S' ^^^^' ^'^^'^ ^>'^i^S ''' ^^ ^^'^' ^^ths or after it hTS dyed, m order to modifv different colors, or to give them lustre. Examples of Tms i il! Hi il It I 78 ARCHIL. among which he found several which might He recommends that the coloring matter should be extracted in will be given i^;^ treating of the compound colors. It is sufficient here to point out how while silks are passed through the archil bath. The same process is performed with a bath more or less charged with this color, for silks already dyed. Archil, in a quantity proportioned to the color desired, is to be boiled in a copper. The clear liquid is to be run off quite hot from the archil bath, leaving the sediment at the bottom, into a tub of proper size, in which the silks, newly scoured with soap, are to be turned raund on the skein-sticks with much exactness, till they have attained the wished- for shade. After this they must receive one beetling at the river. Archil is in general a very useful ingredient in dyeing ; but as it is rich in color, and communicaies an alluring bloom, dyers are often tempted to abuse it, and to exceed the proportions that can add to the beauty without at the same time injuring in a dangerous manner the permanence of the colors. Nevertheless, the color obtained when solution of tin is employed, is less fugitive than without this addition : it is red, approaching to scarlet. Tin appears to be the only ingredient which can increase its durability. The solution of tin may be employed, not only in the dyeing bath, but for the preparation of the silk. In this case, by mixing the archil with other coloring substances, dyes may be obtained which have lustre with sufficient durability. We have spoken of the color of the archil as if it were natural to it ; but it is, really, due to an alkaline combination. The acids make it pass to red, either by saturating the alkali, or by substituting themselves for the alkali. The lichen w^hich produces archil is subjected to another preparation, to make turn- sole (litmus). This article is made in Holland. The lichen comes from the Canary Islands, and also from Sweden. It is reduced to a fine powder by means of a mill, and a certain proportion of potash is mixed with it. The mixture is watered with urine, and allowed to suffer a species of fermentation. When this has arrived at a certain degree, carbonate of lime in powder is added, to give consistence and weight to the paste, which is afterwards reduced into small parallelopipeds that are carefully dried. The latest researches on the lichens, as objects of manufacture, are those of Westring of Stockholm. He examined 150 species, be rendered useful. the places where they grow, which would save a vast expense in curing, package, car riage, and waste. He styles the coloring substance itself cutbear, persio, or turnsole ; and distributes the lichens as follows : — 1st. Those which, left to themselves, exposed to moderate heat and moisture, may be fixed without a mordant upon wool or silk ; such are the L. ciriereus, amaianta, ventosus, corallinus, wesirivgiiy saxatilis, conspassus, bar' batus, plicatus, vnlpinus, Sec. 2. Those which develop a coloring matter, fixable likewise without mordant, but which require boiling and a complicated preparation ; such are the lichens subcameus, dillenii, farinaceuSf jubaius, fur/uraceus, pulmonareusy comigatus, cocciferus, digilatus, ancia- lis, aduncus, &.C. Saltpetre or sea-salt is requisite to improve the lustre and fastness of the dye given by this group to silk. 3. Those which require a peculiar process to develop their color ; such as those which become purple through the agency of stale urine or ammonia. Westring em- ployed the following mode of testing : — He put three or four drachms of the dried and powdered lichen into a flask ; moistened it with three or four measures of cold spring water ; put the stuff to be dyed into the mixture, and left the flask in a cool place. Sometimes he added a little salt, saltpetre, quicklime, or sulphate of copper. If no color appeared, he then moistened the lichen with water containing one twentieth of sal ammoniac, and one tenth of quicklime, and set the mixture aside in a cool place from eight to fourteen days. There appeared in most cases a reddish or violet colored tint. Thus the lichen cinereus dyed silk a deep carmelite, and wool a light carmelite ; the l.physodes gave a yellowish-gray; the pustulatus, a rose red; sanguinarius, gray; tartareusj found on the rocks of Norway, Scotland, and England, dyes a crimson-red. In Jutland, cutbear is made froin it, by grinding the dry lichen, sifting it, then setting it to ferment in a close vessel with ammonia. The lichen must be of the third year's growth to yield an abundant dye ; and that which grows near the sea is the best. It loses half its weight by drying. A single person may gather from twenty to thirty pounds a day in situations where it abounds. No less than 2,239,685 pounds were manufactured at Chrisliansand, Flekkefiort, and Fakrsund, in Norway, in the course of the six years prior to 1812. Since more solid dyes of the same shade have been invented, the archil has gone much into disuse. Federigo, of Florence, who revived its use at the beg^Inning of the fourteenth century, maJe such an immense fortune by its preparation, that his family became one of the grandees of that city, under the name of Oricellarii, or Rucellarii. For more than a century Italy possessed the exclusive art of making archil, obtaining the lichens from the islands of the Mediterranean. According to an official report of 1831, Teneriffe furnished annually 500 quintals (cwts.) of lichen j ARROW ROOT. 79 the Canary Isles, 400; Fuerta Santura, 300 ; Lancerot. 300: Gomera, 300; Isle of Ferro. 800. This business belonged to the crown, and brought in a revenue of 1500 piastres. The farmers paid from 15 to 20 reals for the right to gether each quintal At that time the quintal fetelied in the London market 4/. sterling. Archil is perhaps too much used in some cloth factories of England, to the discredit of our dyes It is said, that by its aid one third of the indigo may be saved in the blue vat • but the color is so much the more perishable. The iine soft tint induced upon much of the black cloth by means of archil is also deceptive. One hail-pound of cudbear will dye one pound of woolen cloth. A crimson red is obtained by adding to the decoction of archil a little salt of tin (muriate), and passing the cloth through the bath, after it has beeu prepared by a mordant of tin and tartar. It must be af- terwards passed through hot water. , ^ . ,. u ^ • ^ • The lichens have been of late years subjects of a multitude of interesting but intri- cate chemical researches, and a number of new compounds have been produced, as lecanorin, from lecanora, and variolaria, with which colorless substance a purple red is formed by the action of ammonia and the air; also erythrine and erythryline from several sorts of lichens, especially parmeliar ocella and tartarean, which afford, when digested with ammonia, a bright red dye, but if treated with alcohol only^ a white granular precipitate, when the solution is slowly evaporated ; orcine and orceine are somewhat analogous products, also crystallizable, which may be obtained from the variolaria dealbafa, by decomposition of the lecanorine. It has a sweet nauseous taste, and melts into a colorless fluid, which may be distilled. It is soluble both in water and alcohoL Orceine by means of ammonia and air forms archil. Dyeing with archil with the aid of oil has been patented by Mr. Ligbtfoot, on the same principle as has been so long used in the Turkey red cotton dye. He has also recourse to metallic and earthy bases, with what success I have not heard. Alumina- ted potash is likewise mentioned along with a great variety of other chemicals. ARDENT SPIRIT. Alcohol of moderate strength. AREOMETER OF BAUME'. This scale is much used by the French authors. Specific Gravity Numbers corresponding with Baume's Areometric Degrees. Liquids denser than Water. | Less dense than Water. De- Speuifie De- Specific De- Specific De- Specific De- Specific grees. gravity. grees. gravity. grees. gravity. grees. gravity. grees. gravity. 10000 26 1-2003 52 1-5200 10 1-0000 36 0-8488 1 10066 27 12160 53 1-5353 11 09932 37 0-8139 2 1-0133 28 1-2258 54 1-5510 12 0-9865 38 08391 3 10201 29 1-2358 55 1-5671 13 09799 39 0-8343 4 10270 30 1 2459 56 158.33 14 0-9733 40 0.8295 5 10340 31 1-2562 57 1-6000 15 09669 41 42 8S49 6 10411 32 1-2667 58 1-6170 16 0-9605 0-8202 7 10483 33 1-2773 59 1-6344 17 0-9542 43 0-8156 8 10556 34 1-2881 60 1-6522 18 0-9480 44 8111 9 10630 35 1-2992 61 1-6705 19 0-9420 45 0-8066 10 10704 36 1-3103 62 1-68S9 20 0-9359 46 0-8022 11 1-0780 37 1-3217 63 1-7079 21 09300 47 0-7978 12 1-0857 38 1-3333 64 1-7273 22 0-9241 48 0-7935 13 10935 39 1-3451 65 17471 23 0-9183 49 0-7892 14 1 1014 40 1-3571 66 1-7674 24 0-9125 50 0-7849 15 16 1-1095 41 13694 67 1-7882 25 0-9068 51 52 0-7807 1-1176 42 1-3818 68 1-8095 26 09012 0-7766 17 1 1259 43 1-3945 69 1-8313 27 0-8957 53 0-7725 18 1 1343 44 1-4074 70 1-8537 • 28 0-8902 54 0-76»l 19 11428 45 1-4206 71 1-8765 29 0-8848 55 0-7643 20 11515 46 1-4339 72 1-9000 30 0-8795 56 07604 21 11603 47 1-4476 73 1-9241 31 0-R742 57 0-7656 22 11692 48 1-4615 74 1-9487 32 0-8690 58 0-7526 23 11783 49 1-4758 75 1-9740 33 08639 59 0-7487 24 1 1875 50 1-4902 76 20000 34 0-8588 60 0-7449 1 « I 1968 51 1-4951 35 0-8538 61 0-7411 ARGILLACEOUS EARTH. The earth of clay, called in chemistry alumina, because it is obtained in greatest purity from alum. ARGOL. Crude tartar ; which see. ARMS. Weapons of war. See Fire-Arms for an account of this manufacture. ARRACK. A kind of intoxicating beverage made in India, by distilling the ferment- ed juice of the cocoa-nut, the palmyra tree, and rice in the husk. ARROW ROOT. The root of the maranta arundinacea, a plant which grows in the "West Indies, furnishes, by pounding in mortars and elutriation through sieves, a peculiar species of starch, commonly, but improperly called arrow root. It is reckoned more ' fe i 80 ARROW ROOT. noiirislimg than the starch of wh<.at or potatoets and is generallj- also freer from pe culiar taste or flavor. The fresh root consists, according to Benzon, of 007 of vola tiJe oil ; 26 of starch (23 of which are obtained in the form of powder while the other 3 must be extracted from the parenchyma in a paute by boiling water)- 1-58 pi vegetable albumen; 0-6 of a gummy extract; 0'25 of chloride of calcium' 6 of insoluble fibrme ; and 65*6 of water. ^ This plant has been lately cultivated with great succoss, and its root manufactured in a superior manner, upon the Hopewell estate, in the island of St Vincent. It grows there to the height of about 3 feet, and it sends down its tap roots from 12 to 18 inches into the ground. Its maturity is known by the flagging and falling down 1^ rif ^''^'' f ''.^':^°^^^'*^^ *^^^» place when the plant is from 10 to 12 months Old. Ihe roots being dug up with the hoe are transported to the washing-house, where they are thoroughly freed from all adhering earth, and next taken individually nto the hand, and deprived by a knife of every portion of their skins, while every unsound part is cut away. This process must be performed with great nicety, for the cuticle contains a resinous matter, which imparts color and a disagreeable flivor to the fecula, which no subsequent treatment can remove. The skinned roots are thrown into a large cistern, with a perforated bottom, and there exposed to the aetion of a copious cascade of pure water, till this runs off quite unaltered. The cleansed roots are next i)ut into the hopper of the mill, and are subjected to the pow- erful pressure of two pairs of polished rollers of hard brass; the lower pair of rollers l>eing set much closer together than the upper. (See the accompanying figure.) The starchy matter is thus ground into a pulp which falls into the receiver placed be- neath, and IS thence transferred to large fixed copper cylinders, tinned inside, and pertorated at the bottom with numerous minute orifices, like a kitchen drainer. Within these cylinders, wooden paddles are made to revolve with great velocity by the power of a water-wheel, at the same time that a stream of pure water is admit- ted trom above The paddle arms beat out the fecula from the fibres and parenchyma ot the pulp, and discharge it in the form of a milk through the perforated bottom of the cylinder. This starchy water runs along pipes, and then through strainers of fine muslin into large reservoirs, where, after the fecula has subsided, the superna- tant water is drawn off, and fresh water being let on, the whole is agitated and left again to repose. This process of ablution is repeated till the water no longer ac- quires any thing from the fecula. Finally, aU the deposits of fecula of the day's work are collected into one cistern, and, being covered and agitated with a fresh charge of water, are allowed to settle till next morning. The water being now let ott the deposit is skimmed with palette knives of German silver, to remove any of the superficial parts, m the slightest degree colored; and only the lower, purer, and denser portion is prepared by drying for the market. The drying-house on the Hopewell estate is constructed like the hothouse of an English garden But instead P'^nts, It contains about 4 dozen of drying pans made of copper, Ti feet by 4i, and tinned mside Each pan is supported on a carriage, having iron axles. wi^I lignum vit« wheels, like those of a railway carriage, and they run on rails. Imme- diately alter sunrise, these carriages with their pans, covered with white gauze, to exclude dust and insects, are run out into the open air, but if rain be apprehended, they are run back under the glazed roof In about 4 days the fecula is thorouehly dry and ready to be packed, with German silver shovels, into tins or American flour barrels, lined with paper attached with arrow root paste. The packages are never sent to this country m the hold of the ship, as their contents are easily tainted by noisome effluvia, of sugar, &c. By such a skilful series of operations, and by such precautions, the arrow root thus manufactured may vie with any similar preparation in the Bermudas or any other part of the world. I have found it, on of fooT ^*'^^'' ^^ ^^ ^"^"^' P*'^^^^"^» ^"^ agreeable, and a most wholesome article Fig. 26. Plan of arrow root grinding-mill, and of 2 sets of copper cylinder wash- ing-machines, with the connecting machinery for driving them ; the washing agitator being driven from the connecting shaft with leathern belts. Fig. 27. End elvevation of arrow root mill, with wheels and pinions, disengaging lever, Ac. Fig. 28. End elevation of copper washing-cylinders, with pres8-framin|, «kc. The washing-cylin- dere are 6i feet long and 3i in diameter. The mill-rollers are 3 feet long and 1 foot m diameter. ° ARROW ROOT. 81 i The uses of arrow root are too well known and acknow- ledged to require recounting here. It is the most elegant and the richest of all the feculas, and being now mann- I factured, with the advantage of excellent machinery, and J abundance of pure water, in the fertile island of St. Vincent, it may he brought into our market at a much more moderate price than it has heretofore been supplied from less favored localities. The Bermuda arrow root is treated necessarily with rain water collected in tanks, and therefore is occa- sionally soiled with insects, from which the St. Vincent arti- cle is entirely free. (" I li ■w 82 ARSEN^IC. The presence of potato starch in arrow root may be discovered by the microsc* pe. Arrow root consists of regular ovoid particles of nearly equal size, whereas po^to Btarch consists of particles of an irregular ovoM or truncated form, exceedingly irre- gular in their dimensions, some being so lai^e as ^^^ of an inch, and others only -q\j^. But the niost convenient test is dilute nitric acid of 1 -10 (about the strength of single aquafortis), which, when triturated in a mortar with the starch, forms immediately a transparent very viscid paste or jelly. Flour starch 6xliibits alike appearance. Arrow root, however, forms an.opaque paste, and takes a much longer time to become viscii Arrow root may be distinguished from potato starch, not only by the different size of its particles, but by the difference of structure. Their surfaces in the arrow root •re smooth, and free from the streaks and furrows seen in the potato particles by a good microscope. The arrow root, moreover, is destitute of that fetid unwholesome oil extractable by alcohol from potato starch. Liebig places the powers of arrow root, as a nutriment to man, in a very remarka- ble point of view, when he states that 15 pounds of flesh contain no more carbon for supplying animal heat bv its combustion into carbonic acid in the system than 4 pounds of starch ; and that if a savage, with one animal and an equal weight of •tarch, could maintain life and health for a certain number of days, he would be eompelled, if confined to flesh alone, in order to procure the carbon necessary for respiration during the same time, to consume five such animals. Quantities imported - Quantities exported - Retained for consumption Net revenue ARSENIC. This metal occurs native, in the state of oxide, and also combined with aalphur under the improper name of yellow and red arsenic, or orpiment and realgar. Arsenic is associated with a great many metallic ores ; but it is chiefly extracted fi-om those of cobalt, by roasting, in which case the white oxide of arsenic, or, more cor- rectly, the arsenious acid is obtained. This acid is introduced occasionally in small quantities into the materials of flint glass, either before their fusion, or in the melting pot It serves to peroxidize the iron oxide in the sand, and thereby to purify the body of the glass ; but an excess of it makes the glass milky. ScheelcH green is a combination of this arsenious acid with oxide of copper, or an arsenit^ of copper, and is described under this metal. Arseniate of potash is prepared, in the small wa}^, by exposing to a moderate heai^' in a crucible a mixture of equal parts of white ai-senic and nitre in powder. After fusion the crucible is to be cooled ; the contents being dissolved in hot water, and the solution filtered, will afford regular crystals on cooling. According to M. Berze- lius, they are composed of arsenic acid, 63-87 ; potash, 26*16; and water, 997. It ia an acidulous salt, and is hence usually called the binarseniate, to denote that its com- position is 2 atoms of arsenic acid, and 1 of potash. Tliis article is prepared upon the great scale, in Saxony, by melting nitre and arsenious acid together in a cylinder of cast-iron. A neutral arseniate also is readily formed, by saturating the excess of acid in the above salt with potash; it does not crystallize. The acid arseniate is oc- casionally used in calico printing, for preventing certain points of the cotton cloth ft^m taking on the mordant ; with which view it is mixed up with gum water and pipe clay into a paste, which is applied to such places with a block. 1841. 1842. 1843. 1844. cwt — 7953 9236 10274 cwt 334 264 200 cwt. 7561 8499 10018 19 1012 737 623 769 ARSENIC. 88 The extraction of arsenic from the cobalt ores, is performed at Altenberg and Reichen- stein, in Silesia, with an apparatus, excellently contrived to protect the health of the smellers from the vapors of this most noxious metaUic sublunate. . Fiss. 29 to 32 represent the arsenical furnaces at Altenberg. Fig. 29 is a vertical section of the poison tower; fig. 30, a longitudinal section of the subliming furnace a, with the adjoining vault b, and the poison tower in part at w; fig. 31, the transverse section of the furnace a, of yig. 30 ; fig. 32, ground plan of the furnace a, wher^- the lefX half shows the part above, and the right the part below the muffle or oblong retort; b' is the upper view, b" the ground plan of the vault b, of^ig. 30; m, n, the base of the poison tower. In the several figures the same letters denote the same objects; a is the muffle ; 6 is its mouth for turning over the arsenical schlich, or ground ore ; cc c, fire draughts or flues ; rf, an aperture for charging the muffle with fresh schlich ; c, the smoke chimney ; /, two channels or flues for the ascent of the arsenious fumes, which proceed to otlver two flues g, and then terminate both in ft, which conducts the fumes into the vault b. They issue by the door t, into the conduit fc, thence by / into the spaces m, n, o, p, q, r, of the tower. The incondensable gases escape by the chimney, *. The cover ^ is removed afler completion of the process, in order to push down the pre- cipitate into the lower compartments. The arsenious schlichs, to the amount of 9 or 10 cwt. for one operation (1 roaai-post, or roasting round), are spread 2 or 3 inches thick upon the bottom of the muffle, Heated with a brisk fire to redness, then with a gentler heat, in order to oxydize completely, before subliming, the arsenical ore. With this view the air must have free entrance, and the front a|)erture of the muffle must be left quite open. After 11 or 12 hours, the cal- cined materials are raked out by the mouth of the muffle, and fresh ones are introdcced hy the openings indicated above, which are closed during the sublimation. The arsenious acid found in these passages is not marketable till it be re-sublimed in large iron pots, surmounted with a series of sheet iron drums or cast-iron cylinders, upon the sides of which the arsenic is condensed in its compact glassy form. The top cylinder is furnished with a pipe, which terminates in a condensing chamber. Figs. 33, 34, represent the arsenic refining furnaces at Reichenstein. Fig. 33 .shows I' (' 84 ARSENIC- at A, a vertical section of the (\imace, the kettle, and the surmounting drums or cylinders ; over b it is seen in eleva- tion ; fig. 34 is a ground plan of the four fireplaces, a is the grate ; 6, the ash-pit; c, the openings for firing; d, the fire-place ; e, iron pots or kettles which are charged with the arsenious powder; /, the fire-flues proceeding to the common chimney g; A, iron cy- linders; », caps; ky pipes leading to the poison vent I ; m, openings in the pipes for introducing the probing wires. The conduct of the process is as follows:— The pot is filled nearly to its brim with 3| cwt. of the arsenic meal, the cylinders are fitted on by means of their handles, and luted to- gether with a mixture of loam, blood, and hair ; then is applied first a gentle, and after half an hour, a strong fire, whereby the arsenic is raised partly in the form of a white dust, and partly in crystals ; which, by the contin jance of the heat, fuse together into a homo- geneous mass. If the fire be too fee- ble, only a sublimate is obtained ; but, if too violent, much of the arsenic is volatilized into the pipes. The work- men judge by the heat of the cylin- ders whether the operation be going on well or not. After 12 hours the furnace is allowed to cool, provided the probe wires show that the subli- mation is over. The cylinders are then lifted oflT, and the arsenious glass is detached from their inner surface. According to the quality of the poison - flour, it yields from f to | of its weight Of the glass or enamel. Should any dark particles of metallic arsenic be intermixed with the glass, a fresh sublimation must be had recourse to. The following is the product in cwts. of arsenious acid, at Altenberg and Reichenstein, in Silesia, in the years White arsenic in a glassy 1835. 1826. 1827. 1828. 1829, 1830. 1831. 1632. state- ... 2632 1703 2686 1900 2070 2961 3337 2730 Sublimed arsenic in pow- • der- m 27 33 31 30 44 69 38 Yellow arsenical glass - 112 11 56 86 313 60 219 Red arsenical glass 3 - - • 28 Arsenical Foisov {detection o/).— It is well known that fluids mixed with glutinotis matter are very liable to froth up when hydrogen is disengaged in them from the mutu- al action of zinc and a dilute acid ; and that the froth obstructs the due performance of the experiment of Marsh. It is equally known, that much of the arsenic contained in the poisonous liquid so tested escapes condensation and eludes measurement A com- naittee, appointed by the Prussian government, have contrived an ingenious modifica- tion of Marsh's apparatus, which I have simplified into the annexed form:— a is a narrow glass cyhnder, open at top, about 10 inches high, and U or 1^ inch diameter in- side ; B 18 a glass tube, about 1 inch diameter outside, drawn to a point at bottom, and shut with a cork at top. Tlirough the centre of this cork, the small tube o passes down air-tight, and is furnished at top with a stop-cock, into which the bent small tube of glass (without lead) e is cemented. The bent tube f is joined to the end of b with a collar of caoutchouc, or a perforated cork, which will be found more convenient The manner of using this apparatus is as follows :— -Introduce a few oblong slips of zinc, free from arsenic, into b, and then insert its air-tight cock with ARSENIC. 85 suspected liquid, acidulated with dilute hy- drochloric or sulphuric acid (each pure) as will rise to the top of the cork, after b is full, and immediately shut the stop-cock. The generated hydrogen will force down the liquid out of the lower orifice of b into a, and raise the level of it above the cork. The extremity of the tube f being dipped be- neath the surface of a weak solution of ni- trate of silver, and a spirit-flame being pla- ced a little to the left of the letter e, the stop-cock is then to be slightly opened, so that the gas which now fills the tube b may escape so slowly as to pass olf in separate smaU bubbles through the silver solution. By this means the whole of the arsenic con- tained in the arseniuretted hydrogen will be deposited either in the metallic state upon the inside of the tube e, or with the silver into the characteristic black powder. The first charge of gas in b being expended, the stop-cock is to be shut, till the liquid be again expelled from it by a fresh disengage- ment of hydrogen. The ring of metallic ar- senic deposited beyond e may be chased on- wards by placing a second flame under it, JVI/ and thereby formed into an oblong brilliant ''" -*'^ steel-like mirror. It is evident that by the patient use of this apparatus the whole ar- senic in any poisonous liquid may be collected, weighed, and subjected to every kind of chemical verification. If f be joined to e by means of a perforated cork, it may readily be turned about, and its taper point raised into a position such as when the hydrogen issuing from it is kindled, the flame may be made to play upon a sur- face of glass or porcelain, in order to produce the arsenical mirror. Or the preceding process may be made supplementary to that of boiling the arse- nical foul liquor, acidulated with hydrochloric acid upon slips of clean copper, whereby the arsenic is precipitated upon the copper in a metallic film or thin crust more or less brilliant If one of the slips of copper thus coated be placed in the tube b of the above described apparatus, it will give off its arsenic without the annoyance pro- duced by the frothing up of a glutinous mixture. Arsenic {detection of y— It is now generally known in this country, that towards the close of last year Professor Reinsch has proposed an entirely new method of detect- ing arsenic ; which consists in acidulating any suspected fluid with hydrochloric acid, heating in it a thin plate of bright copper, upon which the arsenic is deposited in the form of a thin metallic crust, and then separating the arsenic from the copper in the state of oxide, by subjecting the copper to a low red heat in a glass tube. Organic fluids and solids, suspected to contain arsenic, may be prepared for this purpose by boiling them for half an hour with a little hydrychloric acid ; solid matters being cut into small shreds, water being added in suflBcient quantity to let the ebullition go on quietly, and care being taken to continue the boiling until the solids are either dis- solved, as generally happens, or are reduced to a state of minute division. Nothing can be more simple, easy or precise than the method of Reinsch. It is also exceedingly delicate, more so than is ever likely to be necessary in any medico-legal in- vestigation ; for it is adequate to detect a 250,000th part of arsenic in a fluid. It is also perfect in another respect : it does not leave any arsenic in the subject of analysis; none, at least, which can oe detected by any other means, even by the most debcate process yet proposed, that of Mr. Marsh. Cut the copper, on which the areenic is deposited, into small chips, so that they may be easily packed in the bottom of a small glass tube, and apply a low red heat A white crystalline powder sublimes ; and if this be examined in the sunshine, or with a candle near it a magnifier of four or five powers will enable the observer to distinguish the equilateral triangles composing the facets of the octahedral crystals, which are formed by arsenious acid when it sublimes. Sometimes the three equal angles, com- posing a corner of the octahedron, may be seen by turning the glass in various direc- tions. If triangular facets cannot be distinguisned, owing to the minuteness of the crystals, then shake out the copper cliips, close the open end of the tube with the finger, and heat the sublimed powder over a very minute spirit lamp flame, chasing it J u ARSENIC. tip and down the tube till crystals of adequate size are formed. Next boil a little di»- tiJled -water in the tube over the part where the crystalline powder is collected • and -when the solution is cold divide it into three parts, to be tested with ammoniacal nitrate of silver, ammoniacal sulphate of copper, and sulphuretted hydrogen, either in the state of gas or dissolved in water. In boiling organic substances in the weak hydrochloric acid care must be taken to ascertain that there is a decided excess of acid always present. Twofluidrachmsto every 8 oz. of hquid are in general sufficient; but if the organic matter be an animal texture in a state of decay, a much larger quantity of acid may be necessarv, owing to the pre- sence of ammonia, which tends gradually to neutralize the acid as the solution goes on. Kemsch does not advise filtration of the fluid after the acid has acted sufficiently on the subject of analysis. But notwithstanding the delay occasioned by filtration, this seems to me advisable inmost instances, otherwise organic particles are apt to attach them- selves to the copper, and thus give rise to empyreuma, when the metallic arsenic is driven oflF by heat The most convenient form for using the copper is that of copper leaf; but ordinary plates of copper may be easily made of any degree of fineness by immersing them for a time in dilute nitric acid. Where the quantity of arsenic in the fluid 18 supposed to be small, nearly half an hour should be allowed to elapse before the copper is removed. Before applying the sulphuretted hydrogen as a test to the solution of the sublimed oxide, the solution must be acidulated with hydrochloric or acetic acid. In every case the whole process should be applied in the first instance to distilled water, acidulated with the hydrochloric acid to be employed afterwards ; and if the copper be tarnished, a purer acid must be obtained, or the copper must be subjected to the subsequent steps of the process, in order to ascertain whether the tarnishing be occasioned by arsenic or not. Arsenical and Antimonial Spots {distinguishing reactions ofl.—li a drop of bromine is placed on a saucer, and a capsule containing arsenical spots inverted over it, the spots take a very bright lemon-yellow tinge in a short time. Antimonial spots, under the same circumstances, are acted on much more rapidly (in about five seconds at a temperature of 52° F.), and assume an orange shade. Both become colorless if exposed to the air, and are again restored if treated with a strong solution of sulphuretted hydrogen. The secondary yellow of the arsenical spots, as observed by Lassaigne, disappears on the ad- dition of ammonia, whilst that of antimonial spots remains untouched. A concentrated solution of iodate of potash turns arsenical spots of a cinnamon-red, and dissolves them almost immediately. On antimonial spots it has no visible action within 3 or 4 hours. Solution of the hypochlorites (chlorides) of soda and lime and chlorine water dissolve arsenical spots instantaneously, leaving those of antimony. A concentrated solution of the chlorate of potash gradually acts upon arsenical spots, but not upon those of anti- ™oiiy. The nitroprusside of potassium, on the other hand, slowly dissolves antimony, producing no perceptible effect upon arsenic. The statement of Bischoff, that arsenicai spots were soluble, antimonial insoluble, in a solution of the chloride of sodium, could not be verified, as, after repeated trials, it was found to leave both not perceptibly aff^ected. The chloride of barium, the hydrochlorate and the sulphite of ammonia, afforded likewise no distinguishing action. The nitrate of ammonia dissolves arsenical more rapidly than antimonial stains. Of these reactions the most decisive are those of iodate of potash, hypochlorites of soda and lime, and fresh chlorine water. Arsenic, Tin, and Antimony [qualitative detertnination of). — Although analytical chemistry possesses several methods of distinguishing between tin, antimony, and arse- nic, I am not acquainted with any process by which these three metals, when they occur together, can be recognized with the same ease and quickness as in the case of most other metals. At the same time, the frequent occurrence of these three metals together renders a quick mode of detecting them highly desirable. The following may be viewed as a small contribution towards this object. With regard to the discrimination of tin and antimony, this is founded on the solu- bility of metallic tin in strong muriatic acid, and the insolubility of antimonial stains, obtained according to Marsh's method in hypochlorite of soda. • When the muriatic solution of the two metals is treated with some metallic zinc, they are both precipitated, the antimony with disengagement of antiraoniuretted hydrogen. When the precipitation is made in a small apparatus for the disengagement of hydrogen, the antimony is readily detected by the black stains insoluble in hypochlorite of soda, which it produces upon a piece of porcelain. When subsequently the precipitated metallic powder of tin and antimony is boiled with strong muriatic acid, only tin dis- solves, forming protochloride, which, after subsequent dilution with water, is recog- nized by the brownish-black precipitate produced by sulphuretted hydrogen. Neither of these reactions are modified by the presence of arsenic. The detection of arsenic when antimony is present, is founded upon a remarkable difference which these two metals exhibit towards nascent hydrogen when the latter is ARTESIAN WELLS. 87 disengaged from an alkaline liquid. When a strong alkaline solution of antimony is heated with metallic zinc, antimony is precipitated simultaneously with a lively disen- gagement of pure hydrogen, which does not show the slightest reaction of antimoniu- retted hydrogen. If, on the contrary, a substance containing arsenic acid is mixed with an excess of potash and some finely-divided zinc, the hydrogen given off on the applica- tion of heat is abundantly charged with arseniuretted hydrogen. The presence of this latter is ascertained most simply by holding a strip of paper dipped in nitrate of silver over the arseniferous mixture of potash and zinc ; with the slightest trace of arsenie the paper is colored distinctly black. AKlfelAN WELLS. Under this name is designated a cylindrical perforation, bored vertically down through one or njore of the geological strata of the earth, till it passes into a porous gravel bed containing water, placed under such incumbent pressure as to make it mount up through the perforation, either to the surface or to a height con- venient for the operation of a pump. In the first case, these wells are called spouting or overflowing. This property is not directly proportional to the depth, as might at first eight be supposed, but to the subjacent pressure upon the water. We do not know ex- actly the period at which the borer or sound was applied to the investigation of subter- ranean fountains, but we believe the first overflowing wells were made in the ancieDt French province of Artois, whence the name of Artesian. These wells, of such impor- tance to agriculture and manufactures, and which cost nothing to keep them in condition, have been in use, undoubtedly, for several centuries in the northern departments of France, and the north of Italy ; but it is not more than 50 or 60 years since they became known in England and Germany. There are now a great many such wells in London and its neighborhood, perforated through the immensely thick bed of the I^ndon clay, and even through some portions of the subjacent chalk. The boring of such wells has given much Insight into the geological structure of many districts. The formation of Artesian wells depends on two things, essentially distinct from each other: 1. On an acquaintance with the physical constitution, or nature, of the mineral structure of each particular country ; and, 2. On the skilful direction of the processes by which we can reach the water level, and of those by which we can promote its ascent in the tube. We shall first treat of the best method of making the well, and then offei some general remarks on the other subjects. The operations employed for penetrating the soil are entirely similar to those daily practised by the miner, in boring to find metallic veins ; but the well excavator must re- sort to peculiar expedients to prevent the purer water, which comes from deep strata, mingling with the cruder waters of the alluvial beds near the surface of the ground, as also to prevent the small perforation getting eventually filled with rubbish. The cause of overflowing wells has been ascribed to a variety of c'u-cumstances. But, as it is now generally admitted that the numerous springs which issue from the ground proceed from the infiltration of the waters progressively condensed in rain, dew, snow, &c. ui>on the surface of our globe, the theory of these interior streamlets becomes by no means intricate ; being analogous to that of syphons and water jets, as expounded in the treatises on physics. The waters are diffused, after condensation, upon the surface of the soil, and percolate downwards, through the various pores and fissures of the geological strata, to be again united subterraneously in veins, rills, streamlets, or expanded films, of greater or less magnitude, or regularity. The beds traversed by numerous disjunctions will give occasion to numerous interior currents in all directions, which cannot be re- covered, and brought to the day ; but when the ground is composed of strata of sand, or gravel very permeable to water, separated by other strata nearly impervious to it, reser- voirs are formed to our hand, from which an abundant supply of water may be spontane- ously raised. In this case, as soon as the upper stratum is perforated, the waters may rise, in consequence of the hydrostatic pressure upon the lower strata, and even overflow the smface in a constant stream, provided the level from which they proceed be propor- tionally higher. The sheets of water occur principally at the separation of two contiguous formations; and, if the succession of the geological strata be considered, this distribution of the watei will be seen to be its necessary consequence. In fact, the lower beds are frequently composed of compact sandstone or limestone, and the upper beds of clay. In level countries, the formations being almost always in horizontal beds, the waters which feed the Artesian wells must come from districts somewhat remote, where the strata are more elevated, as towards the secondary and transition rocks. The copious streams condensed upon the sides of these colder lands maybe therefore regarded as the proper reservoirs of our wells. I li ^1 S8 ARTESIAN WELLS. ^^^36 represents the maimer in which the condensed water of the heavens diV oa tributes itself under the surface of our globe. Here we have a geolo- gical section, showing the succession of the several formations, and the sheets or lamince of water that exist at their boundaries, as well as in their sandy beds. The figure shows also very — .■,-,^,---,-. ,■.-■, plainly that the height to which the water reascends in ihe bore of a well depends upon the height of the r&. scrvoir which supplies the sheet of water to which the well is perforated. Thus the well A, having gone down to the aqueous expanse a a, whose waters of supply are de- rived from tlie percolation m, will afford rising waters, which wiU come to the surface; while in the well b, supphed by the sheet p, the waters will spout above the surface, and in the well c they will remain short of it. The same figure shows that these weUs olten traverse sheets of water, which rise to different heights. Thus, in the well c there are live columns of ascending waters, which rise to heights proportional to the points whence they take their origin. Several of these will be spouting or overflowing, but gome will remain beneath the surface. The situation of the intended well being determined upon, a circular hole is generally dug m the ground, about 6 or 8 feet deep, and 5 or 6 feet wide. In the centre of this note the boring is carried on by two workmen below, assisted by a laborer above, as saown m fig. 37. The handle (fig. 38) having a female screw in the bottom of its iron shank, with a wooden bar or rail passmg through the socket of the shank, and a ring at top, is the general agent to which all the boring implements are to be attached. A chisel 40 4] 46 39 !1 .\l ISi a 48 42 38 g 47 Si Tkf (fig. 39) is first employed, and connect^ to this handle by its screw at top. If the ground is tolerably soft, the weight of the two workmen bearing upon the cross bar, and occasionally forcing it round, will soon cause the chisel to penetrate ; but if the ground is hard or strong, the workmen strike the chisel — down with repeated blows, so as to peck Ijieir way, often changing their situation by walk- ing round, which breaks the stones, or other hard substances, that may happen to obstruct its progress. The labor is very considerably reduced by means of an elastic wooden pole, placed Iwmontany over the well, from which a chain is brought down, and attached to the ring ARTESIAN WELLS. 89 of the handle. This pole is usually made fast at one end, as a fulcrum, by being set into a heap of heavy loose stones ; at the other end the laborer above gives it a slight up and down vibrating motion, corresponding to the beating motion of the workmen below, by which means the elasticity of the pole in rising lifts the handle and pecker, and thereby very considerably diminishes the labor of the workmen, ^eefig. 37. When the hole has been thus opened by a chisel, as far as its strength would permit, the chisel is withdrawn, and a sort of cylindrical auger {fig. 40) attached to the handle (fig. 38), for the purpose of drawing up the dirt or broken stones which have been disturbed by the chisel. A section of this auger is shown in^^. 41, by which the in- ternal valve will be seen. The auger being introduced into the hole and turned round by the workmen, the dirt or broken stones will pass through the aperture at bottom (snown at fig. 42), and fill the cylinder, which is then drawn up, and discharged at the top of the auger, the valve i)reventing its escape at bottom. In order to penetrate aeeper into the ground, an iron rod, as a, fig. 43, is now to be attached to the chisel, fig. 39, by screwing on to its upper end, and the rod is also fastened to the handle, fig. 38, by screwing into its socket. The chisel having thus become lengthened by the addition of the rod, it is again introduced into the holej and the operation of pecking or forcing it down, is carried on by the workmen as be- fore. When the ground has been thus perforated, as far as the chisel and its rod will reach, they must be withdrawn, in order again to introduce the auger, fig. 40, to col- lect and bring up the rubbish ; which is done by attaching it to the iron rod, in place of the chisel. Thus, as the hole becomes deepened, other lengths of iron rods are added, by connecting them together, as a 6 are in fig. 44. The necessity of frequently with- drawing the rods from the holes, in order to collect the mud, stones, or rubbish, and the great friction produced by the rubbing of the tools against its sides, as well as the lengths of rods augmenting in the progress of the operation, sometimes to the extent of several hundred feet, render it extremely inconvenient, if not impossible, to raise them by hand. A tripedal standard is therefore generally conslnicted by three scaffolding poles tied together, over the hole, as shown fig. 37, from the centre of which a wheel and axle, or a pair of pully blocks is suspended, for the purpose of hauling up the rods, and from which hangs the fork,^g. 45. This fork is to be brought down under the shoul- der, near the top of each rod, and made fast to it by passing a pin through two little holes in the claws. The rods are thus drawn up, about seven feet at a time, which is the usual distance between each joint, and at every haul a fork, fig. 46, is laid hori- zontally over the hole, with the shoulders of the lower rod resting between its claws, by which means the rods are prevented from sinking down into the hole again, while the upper length is unscrewed and removed. In attaching and detaching these lengths of rod, a wrench, fig. 47, is employed, by which they are turned Kjund, and the screws for- ced up to their firm bearing. The boring is sometimes performed for the first sixty or a hundred feet, by a chisel of 2i inches wide, and cleared out by a gouge of 2^ diameter, and then the hole is widened by a tool, such as is shown at fig. 48. This is merely a chisel, as fig. 39, four inches wide, but with a guide, a, put on at its lower part, for the purpose of keeping it in a perpendicular direction ; the lower part is not intended to peck, put to pass down the hole previously made, while the sides of the chisel operate in enlarging the hole to four inches. The process, however, is generally performed at one operation, by a chisel of four inches wide, as fig. 39, and a gouge of three inches and three quarters. as,^g. 40. * ' It is obvious that placing and displacing the lengths of rod, which is done every time that the auger is required to be introduced or withdrawn, must, of itself, be extremely troublesome, independent of the labor of boring, but yet the operation proceeds, when no unpropitious circumstances attend it, with a facility almost incredible. Sometimes, however, rocks intercept the way, which require great labor to penetrate ; but this is always effected by pecking, which slowly pulverizes the stone. The most unpleasant circumstance attendant upon this business is the occasional breaking of a rod into the liol^, which sometimes creates a delay of many days, and an incalculable labor in draw- mg up the lower portion. When the water is obtained in such quantities and of such quality as may be required, the hole is dressed or finished by passing down it a diamond chisel, funnel mouthed, with a triangular bit m its centre ; this makes the sides smooth previous to putting in lae pipe. This chisel is attached to rods, and to the handle, as before described ; and, m Its descent, the workmen continually walk round, by which the hole is made smooth and cylindrical. In the progress of the boring, frequent veins of water are passed inrough ; but, as these are smaU streams, and perhaps impresnated with mineral sub- stances, the operation is carried on until an aperture is made into a main spring, which will flow up to the surface of the earth. This must, of course, depend upon the level of its source, which, if m a neighboring hill, wiU frequently cause the water to rise up, and produce a continued fountain. But if the altitude of the distant spring happens to i 90 ARTESIAN WELLS. be below the level of the surface of the CTonnd where the boring is effected, it sometimes happens that a m eU of considerable capacity is obliged to be dug down to that level, in order to form a reservoir, into which the water may flow, and whence it must be raisea by a pump; while, in the former instance, a perpetual fountam may be obtaineU. Hence, it will always be a matter of doubt, in level countries, whether water can be procured which would flow near to or over the surface ; if this cannot be ettected, liie process of boring wiU be of little or no advantage, except as an experiment to ascertain In order to keep the strata pure and uncontaminated with mineral springs, the hole is cased, for a considerable depth, with a metallic pipe, about a quarter of an inch Bmaller than the bore. This is generally made of tin (though sometimes of copper or lead) in convenient lengths; and, as each length is let down, it is held by a shoulder resting in a fork, while another length is soldere^to it ; by which means a conlmuous pipe is carried through the bore, as far as may be found necessary, to exclude land spricgs, and to prevent loose earth or sand from falling in, and choking the aperture. Mr. John Good, of Tottenham, who had been extensively employed in boring the earth for water, obtained a patent, in Aug. 1823, for certain improved implements con- trived by him to facilitate his useful labors ; a description of which cannot fail to be in- teresting. , , The figures annexed exhibit these ingenious tools ; fifi. 49 is an auger, to be connected 52 51 50 49 by the screw-head to the length of rods by which the boring is car- ried on. This auger is for boring in soft clay or sand ; it is cylin- A'V n ft drical, and has a slit or opening from end to end, and a bit, or U Y 1 1 W cutting.piece at bottom. When the earth is loose or wet, an auger VI I I of the same form is to be employed, but the slit or opening reduced A HTH ITWH in width, or even without a slit or opening. A similar auger is />^ lUiUI 1^ ^ fc J« used for cutting through chalk ; but the point or bit at bottom should then project lower, and, for that purpose, some of these cylindrical augers are made with moveable bits, to be attached by screws, which is extremely desirable in grinding them to cutting edses. Fig. 60 is a hollow conical auger, for bormg loose sandy soils ; it has a spiral cutting edge coiled round it, which, as it turns, causes the loose soil to ascend up the inclined plane, and yJU r& deposite itself in the hollow within. Fig. 51 is a hollow cylinder US! If or tube, shown in section, with a foot-valve, and a bucket to be raised by a rod and cord attached at the top ; this is a pumping tool, for the purpose of getting up water and sand that would not rise by the auger. When this cylinder is lowered to the bottom of the bore, the bucket is lifted up by the rod and cord, and descends again by its own gravity, having a valve in the bucket, opening upwards, like other lift pumps ; which, at every stroke, raises a quanlitv of water and sand in the cylinder equal to the stroke ; the ascent and descent o! the bucket being limited bv a guide-piece at the top of the cylinder, and two smaU knob* upon the rod which stop against the cross-guide. Fig. 52 is a tool for getting up broken rods. It consists of a small cylindrical piece at bottom, which the broken rod slips through when it is lowered, and a small catch with a knife-edge, acted upon by a back-spring. In rising, the tool takes hold of the broken rod, and thereby enables the workman at top to draw it up. Another tool for the same purpose, is shown at jig. 53, which is like a pair of tongs ; it is intended to be slidden down the bore, and for the broken rod to pass between the two catches, which, pressed by back-springs, will, when drawn up, take fast hold of the broken rod. „ . v * v j Fie. 54 is a tool for widening the hole, to be connected, like all the others, to the end of the length of rods passed down the bore; this tool has two cutting-pieces extending on the sides at bottom, by which, as the tool is turned round in the bore, the earth is peeled away. Fig. 65 is a chisel, or punch, with a projecting piece to be used for penetrating through stone; this chisel is, by rising and falling, made to peck the stone, and pulverize it ; the small middle part break- ing it away first, and afterwards the broad part coming into ac- tion. Fig. 66 is another chisel, or punching tool, twisted on its cutting edge, which breaks away a greater portion of the stone as it beats against it. < ^1 I * ARTESIAN WELLS. 91 The manner of forcing down lengths of cast-iron pipe, after the bore is formed, is shown at fig. 67 ; the pipe is seen below in the socket, at the end of which a block is inserted ; and from this block a rod extends upwards, upon which a weight at top slides. To this weight cords are shown to be attached, reaching to the top of the bore ; where the workmen alternately raise the weight and let it fall, which, by striking upon the block in its middle, beats down the pipe by a succession of strokes ; and when one length of pipe has, by these means, been forced down, another leneth is introduced into the socket of the former. Another tool for the same purpose is shown &tfig. 58, which is formed like an acorn ; the raised part of the acorn strikes against the edge of the pipe, and by thai means, it is forced down the bore. When it happens that an auger breaks in the hole, a tool similar to that shown at^g. 59 is introduced; on one side of this tool a curved piece is attached, for the purposeof a guide, to conduct it past the cylindrical auger ; and at the end of the bther side is a hook, which, taking hold of the bottom edge of the auger, enables it to be drawn up. Wrought iron, copper, tin, and lead pipes, are occasionally used for lining the bore; and as these are subject to bends and bruises, it is necessary to introduce tools for the purpose of straightening their sides. One of these tools is shown at yig. 60, which is a bow, and is to be passed down the inside of the pipe, in order to press out any dents. Another tool, for the same purpose, is shown at^g. 61, which is a double bow, aud may be turned round in the pipe for the purpose of straightening it all the way down ; atfig. 62, is a pair of clams, for turning the pipe round in the hole while driving. When loose stones lie at the bottom of the hole, which are too large to be brought up by the cylindrical auger, and cannot be conveniently broken, then it is proposed to introduce a triangular claw, Sisfig. 63, the internal notches of which take hold of the stone, and as the tool rises, bring it up. For raising broken rods, a tool like^g. 64 is sometimes employed, which has an angular claw that slips under the shoulder of the rod, and holds it fast while drawing up. In raising pipes it is necessary to introduce a tool into the insic'e of the pipe, by which it will be held fast. Fig. 65 is a pine-apple-tool for this purpose ; its surface is cut like a rasp, which passes easily down into the pipe, but catches as it is drawn up ; and by that means brings the pipe with it. Fig. 66 is a spear for the same purpose, which easily enters the pipe by springing; at the ends of its prongs there are forks which stick into the metal as it is drawn up, and thereby raise it. These are the new implements, for which the patent was granted. In the process of boring, there does not appear to be anything new proposed ; but that these several tools are to be employed for boring, packing, and otherwise penetratin?, raising the earth, and extracting broken or injured tools. There are also suggestions for employing long buckets, with valves opening upward in their bottoms, for the purpose of drawing watef from these wells when the water will not flow over the surface ; also lift pumps, with a succession of buckets for the same purpose. But as these suggestions possess little if any novelty, it cannot be intended to claim them as parts of the patent. llie older geological formations are seldom propitious to the construction of Arte- sian wells, on account of the compact massiveness of their rocks, of the few fissures or porous places in them, and of the rarity of filtering strata overiying retentive ones. It 18 therelore vain to attempt the formation of an overflowing sprin?, upon the above prin- ciples, in territories of granite, gneiss, mountain limestone, and basalt. Among transition and secondary formations, such wells will rarely furnish a supply of good water. The latter strata of alternating clay and variegated sandstone contain so much gypsum and rock salt as to impregnate therewith the waters derived from them to an unpalatable 'F^a' *u *f ^" ^^® ^^^^^' calcareous, and argillaceous strata of the Jura limestone, indeed, that borings may most probably be made for brine springs. The hot springs Which burst out of the ground in primitive rocky districts come undoubtedly from a great depth under the surface, and derive their temperature, and also probably their waters, frona the vapors of deep-seated volcanoes in connexion with the sea. A miniature representation of such springs is exhibited in the intermitting fountains of fresh water on the shoulder of Vesuvius. Springs of this kind, which vary with the seasons, may de- rive a portion of their water from the surface of the earth, from which it may sink through clelts m the primitive rocks, till meeting in its descent with stony obstructions and ascend- ing steam, it is forced to remount in a heated state to the day, like the Geisers in Iceland. 1 he most remarkable example of an Artesian well is that recently formed at Crenelle, a suburb at the southwest of Paris, where there was a great want of water. It cost eight years of difficult labor to perforate. The geological strata round the French capital are all of the tertiary class, and constitute a basin, like that shown in fig. 67 Ihe bottom of this basm is chalk ; a a are tertiary strata above the chalk ; b b, chalk or cretaceous carbonate of lime ; c c, d d, green sand and clay; e e, oolite and Jura limestone {muschelkalk) ; e a, general slope of the surface of the country from Langrea to Fans ; m a, the level of the sea. Over a circular space, of which Paris is the centre t n 92 ARTESIAN WELLS. S^teSSSSS£SSS2 Pahs I Nogent- sur- troyes. Bar-sur- Provms. Seine. Lusigny. Seine. 67 Plateau de Langres. vel, pebblcsC and fragments oc\oT^^bhavIt.T^ ^^ fl^^tu" """^^^ "'S^ period anterior to any historical re Jrdn^lT,wtt- '^*P'^'*«'l'>y *•>« waters at some ^ttd^etlXfe^iiHSlttS^^^ l:^^^lb^rra:,tf^^;r/rH-dS^^^ tic clay, and finally chalk which fonm f h J kS/T Au ^'^ P^^*^?*^ pure gravel, plas- have slen. Is^o caiculaS^'n frl georj^'l ^^tl^^^ tertiary basin. aS we stratum of chalk whioh /'J^^. geological data could determine the thickness of this perabTobstacle Thel' rienee acluir.^ ''^^^ ^''''''' «° ^^^^'^ i°««- f ours, was in this respectTut a"^^^^ l^Z^ Xr«^'' '' ?'^:;:'' \^"^°' ^'^^ be overcome, was he sure of finS rsu^nl v nf ^ „/ ? . «»^PPo«'ng th.s obstacle to the first place, the strata cd below^tL KY ^ "t^^,t)elow this mass of chalk ? In sary conditions for producing A trsian ^^r^S""""''^^' ^ ^" ^^«" «^^ °" ^^^ "««««■ gravel, or of perviorSimperv?orbe^ds^M aI"i^' «"^«^r"? ^"^'"^ «^^^*7 »°'^^^« ^^ove and, consequently^fromlet lT;IX.t': ZlZttVJ ^'NoTt'th' ''V'^^^;.' the bore at Grenelle is only 34 yards above tht^LZTtlJ •: * i, ' ^^ ^^^ *""'^^^ ^^ tical spring be met with, L ^l^erl^uZV^^^^^^ The necessary works were onmm^nn^A ^;*k u - "-"e eaitns suitace at Grenelle. to each other, anZtirco^rb^'ra fdZ'^wTel-'b^^^^^^ '""«• """."-O ingenious method was adopted for t^ivin^r fiwi. « ? ;^ mechanical power, while an the bore was about 6 inches^ ThTinft^men^.ffil'T.*?!, "^""^Tr ^^^ '^^^"^'^^^ «f rod was changed according t^ the differrt l«f t'l^^^ '"^ ^^^^^ ^^^^^^ ^""g" the form suited for passin^throu^h th! ^^f/ . ""-^'i^^ "^^'^ successively attacked ; able for boring throStfe chalk and flinr.Tn 1 "'^t T' '^'^ ^"''^"^^ ^^'"^ «°«"'t- while a chiseUhaped tool was emnlo^^^^^ "««^ ^<'' the former, was lessened as th^ depth ircTeasTJnd BrnSfthpt ,1^' ^'""'- ^" ^'^^ °^ *»^« ^«<1« so soon as was expecte^d, it bermrrequisre^^^^^ of the bore, in order to permit the work to be suoiS u^ ''''^''*^ ^'^^^ *^^ diameter curred which tried the patience of rhepi^^ctorsT^^^^^^^ ..^f ^^'^'^ ^^■ extended down to a depth of 418 yards thrSw tnbl^4-fi? ' ^i^° *^^ ^^""^ *^»d long rods attached to i^, broke and kll to the Wo m of 7^'*^^'^^^^ ^^^^^ «^^^« necessary to extract the broken parts before any fultheinl ^^'' ""^T^ '^ ^^^^"« difficulty of accomplishing this task mat be cW ved ? fo^^^^^^^ could be made. Tlie were not all extracted until after the constrnriabor nf i / fu ^^'^^""^"^ fragments 1840, in passing through the chali, t^e'Z:^tl:^Zt\T^^^^^^^ I ARTESIAN" WELLS. 98 and before it could be recovered, several months were spent in digging round about it. A similar occurrence created an obstacle which impeded the work for 3 months, but, instead of withdrawing the detached part^ it was f#rcibly driven down among the stratum of gravel. At length, in February, 1841, after eight years' labor, the rods suddenly descended several yards, having pierced into the vault of the subterranean water so long sought after by the indefatigable engineer. A few hours afterwards he was rewarded for all his anxious toils ; for lo ! the water rose to the surface, and dis- charged itself at the rate of 600,000 gallons per hour! The depth reached down was 602 yards, or about three times the height of St. Paul's. The pipe by which the water reaches the surface has been recently carried to a height nearly level with the source of supply. The portion of the pipe above the ground is surrounded with a monumental pagoda of ornamental carpentry, and it discharges a circular cascade of clear water continually into a circular iron reservoir, to be thence conveyed by a lateral pipe to the ground. The water is well adapted for all domestic uses, and it will be unfailing, being supplied from the infiltration of a surface of coun- try nearly 200 miles in diameter. The Artesian wells of Elbeuf, Rouen, and Tours, which were formed many^ years ago, overflow in never-varying streams ; and the an- cient Artesian well at Lillers, in the Pas de Calais, has for about seven centuries fur- nished a constant and equable supply. The opportunity of ascertaining the temperature of the earth at different depths was not neglected during the progress of the works at Grenelle. Thermomv of wrousht iron, which IS 6 inches, and the opening which receives the muffle-plate. Fig. 71, represents the muf- fle or pot, which is 12 inches long, 6 inches broad inside; in the clear 6f : in height 4| inside measure, and nearly 5| in the clear. Fig. 72, the muffle-plate, which is of the same size as the bottom of the muffle. Fig. 13, is a representation of the sliding-door of the mouth-plate, as shown at d, in fig. 68. 69 (iUEilSHIii] ISSSSIIii] l3i](^^S{35l ?6](77](li]|^l^ \2iMMEm EEOEEilll 20 EQfiigiiiTs] mmmEcio] mmiiimm Fig. 74, a front view of the mouth-plate or piece, d,fig. 58. Ptg. 75, a representation of the mode of making, or shutting up with pieces of char- coal, the mouth of the furnace. Fig. 76, the teaser for cleaning the grate. Fig. 77, a larger teaser, which is introduced at the top of the furnace, for keepin*' a complete supply of charcoal around the muffle. "^ Fig. 78, the tongs used for charging the assays into the cups. Fig 79, represents a board of wood used as a register, and is divided into 45 equal compartments, upon which the assays are placed previouslv to their being introduced into the furnace. When the operation is performed, the cupels are placed in the furnace in situations corresponding to these assays on the board. By these means all confusion IS avoided, and without this regularity it would be impossible to preserve the accuracy which the delicate operations of the assayer require. I shall now proceed to a description of a small assay furnace, invented by Messrs. Anfrye and d'Arcet, of Paris. They term it, Le Petit Foumeau a Coupelle. Fig. 80 represents this furnace, and it is composed of a chimney or pipe of wrought iron a, and of the furnace b. It is 17J inches high, and 7f inches wide. The furnace is formed Of three pieces ; of a dome a ; the body of the furnace b ,• and the ash-pit c, which is 1 1 1 1 I i J ■ i I 1 J ff :,|i"' 96 ASSAY. used as the base of the furnace, figs. 80 and 81. The principal piece, or body of the furnace, b, has the form of a hoUow tower, or of a hoUow cylinderf flat ened^uaUv ut the wo opposite sides parallel to the axis, in such a manner that the hSmTsecUon IS elliptical. The foot which supports it is a hollow truncated cone CS inTe manner upon the two opposite sides, and having consequently for its basis two eUipses of diflferent diamew ters ; the smallest ought to be equal to that of the furnace, so that the bottom of the latter may exactly fit it. The dome, which forms an arch above the furnace, has also its base ellip> tical, while that of the superior orifice by which the smoke goes out preserves the cylindrical form. The tube of wrought iron is 18 inches long and 2^ inches diameter, having one of its ends a little enlarged, and slightly conical, that it may be exactly 5 fitted or jointed upon the upper part of the furnace dome d, fig. 80. At the union of the conical and cylindrical parts of the tube, there is placed a small gal- lery of iron, e,fig. 80, 81. See also a plan of it, fig. 82. This gallery is both in- genious and useful. t^P A,;L.! ?L ??/ '"^v '' ""^'''^ ^'^. ^^""^ «""^^'^ '^""n? the ordinary work of nrLprZ' Vv.'^'°^^A^ ^"^« ^^' inuflle,wheS it is brought mto hs 11211 ?h! T ^''''•mI ^."^' .^^""''f ^^'' ^^"^^y i^ ^ 'P' '^"^ ^"r^ ^^^ ^«^^^°& «^ the furnace, with the mouth! piece, of which the face is seen at n,fig. 81. ^»^ui thaT^lff thfZffll^^?.^"'"r^'/^; ?^' P^^s^jjts several openings, the principal of which is that of the muffle ; it is placed at t ; it is shut with the semicircular door L fiR. 80 and Xrthe'drnr.r' ^% ?'• !r ^^i ^^ '"^^ ^P^^^^^^ ^^ the taWe or she^;Cn fwil c-^r ^ ^'""^!'''"?^t^°^*^'^^'^^^^ the letter q, fig, 81, sh^s dlffl^Hpr'tr r?f •''''i'"-^^ ^^f ',^""'' ^^'^»^ °^^^s P«rt of the fumlce. Imm^ n^ nfthplrlt f ' ^s a horizontal sUt, /, which is pierced at the level of the upper part of the grate, and used for the mtroduction of a slender rod of iron, that the erate aT^,%rfo:iT8^^- ™^^^^^^"^ ^^ ^^^^ at pleasure, by the wed Je rl^r^f^^ Upon the back of the furnace is a horizontal slit/,, fig. 81, which supports the fii«. brick, *, and upon which the end of the muffle, if necessary, may rest : u.fig. 81, isX opening m the furnace where the muffle is placed. "^^ ' Th?di^pn° l^^'pfTf ir ^^^ JT"'^ '^ \^ ""^P^" '■ fi^' ^3, is a horizontal view of it of thP^?: T • f 'P^^l^^termme the general form of the furnace, and thickness of the grate. To give strength and solidity to the grate, it is encircled by i bar or hoop of ASSAY. •r iron. There is a groove in which the hoop of iron is fixed. The holes of the grate are truncated cones, having the greater base below, that the ashes may more easily fall in- to the ash-{)it. The letter v, /<;e is granular and of a dead white, and if it separates readily from the cupel. After the lead is put into the cupel, it gets immediately covered with a coat of oxyde, which resists the admission of the silver to be assayed into the melted metal ; so that the alloy cannot form. When a bit of silver is laid on a lead bath in this predicament, we see it swim about for a long time without dissolving. In order to avoid this result, the silver is wrapped up in a bit of paper ; and the carbureted hydrogen generated by its combustion reduces the film of the lead oxyde, gives the bath immediately a bright me- tallic lustre, and enables the two metals readily to combine. As the heat rises, the oxyde of lead flows round about over the surface, till it is ab- J TT li 98 ASSAY. sorbed by the cupel. When the lead is wasted to a certain desrree, a very thin film of it only remains on the silver, which causes the iridiscent appearance, like the colors of goap-bubbles ; a phenomenon, called by the old chemists, fulguration. When the cupel cools in the progress of the assay, the oxygenation of the lead ceases; and, instead of a very liquid vitreous oxyde, an imperfectly melted oxyde is formed, which the cupel cannot absorb. To correct a cold assay, the temperature of the furnace ou'^ht to be raised, and pieces of paper ought to be put into the cupel, till the oxyde of lead which adheres to it be reduced. On keeping up the heat, the assay will resume its ordi- nary train. Pure silver almost always vegetates. Some traces of copper destroy this property, which is obviously due to the oxygen which the silver can absorb while it is in fusion^ and which is disengaged the moment it solidifies. An excess of lead, by removing all the copper at an early stage, tends to cause the vegetation. The brightening is caused by the heat evolved, when the buttoa passes from the liquid to the solid state. Many other substances present the same phenomenon. In the above operation it is necessary to employ lead which is very pure, or at least free from silver. That kind is called poor lead. It has been observed at all times, that the oxyde of lead carries oiT with it, into the cu- pel, a little silver in the state of an oxyde. This effect becomes less, or even disappears, when there is some copper remaining ; and the more copper, the less chance there is of any silver being lost. The loss of silver increases, on the other hand, with the dose of lead. Hence the reason why it is so important to proportion the lead with a precision which, at first sight, would appear to be superfluous. Hence, also, the reason of the at- tempts which have, of late years, been made to change the whole system of silver assays, and to have recourse to a method exempt from the above causes of error. M. d'Arcet, charged by the Commission of the Mint in Paris, to examine into the jus- tice of the reclamations made by the French silversmiths against the public assays, as- certained that they were well founded; and that the results of cupellation gave for the alloys bet wen 897 and 903 thousandths (the limits of their standard coin) an inferior . standard, by from 4 to 5 thousandth parts, from the standard or title which should result from the absolute or actual alloy. The mode of assay shows, in fact, that an ingot, experimentally composed of 900 thousandths of fine silver, and 100 thousandths of copper, appears, by cupellation, to be only, at the utmost, 896 or 897 thousandths; whereas fine silver, of 1000 thousa'ndths, comes out nearly of its real standard. Consequently a director of the Mint, who should compound his alloy with fine silver, would be obliged to employ 903 or 904 thousandths, in order that, by the assay in the laboratory of the Mint, it should appear to have the standard of 900 thousandths. These 3 or 4 thousandths would be lost to him, since they would be disguised by the mode of assay, the definitive criterion of the quantity of silver, of which the government keeps count from the coiner of the money. From the experiments subsequently made by M. d'Arcet, it appears that silver assays always suffer a loss of the precious metal, which varies, however, with the standard of the alloy. It is 1 thousandth for fine silver, 4*3 thousandths for silver of 900 thousandths, 4-9 — for — of 800 — 4-2 — for — of 500 — and diminishes thereafter, progressively, till the alloy contains only 100 thpusandths of silver, at which point the loss is only 0'4. Assays requested by the Commission of the Paris Mint, from the assayers of the prin- cipal Royal Mints in Europe, to which the same alloys, synthetically compounded, were sent, afforded the results inscribed in the following table. Names of the Assayers. F. de Castenhole, Mint Assayer A. R. Vervaez, ditto D. M. Cabrera, Assayer in Spain - - - - - Assayer - - - - - Mr. Bingley, Assay Master Mr. Johnson, Assayer - Inspector of the Mint Assayer of the Mint Assayer of Trade - - - Assayer of the Mint Ditto Cities where they reside. Vienna Madrid Ditto Amsterdam London Ditto Utrecht Naples Ditto Hamburgh Altona Standards found for the Mathematical Alloys^ 950 mill. 900 mill. 800 mill. 946-20 898 40 795- 10 944-40 893-70 789-20 944-40 893-70 788-60 94700 895-00 795-00 946-25 896-25 794-25 933-33 883-50 783-33 945-00 896-50 799-00 945-00 891-00 787-00 945-00 891-00 787-00 946'U 897-^ J 798-44 942- i 894-00 790 ASSAY. 99 n^ese results, as wel as those in still greater numbers, obtained from the ablest Parisian assayers, upon identical alloys of silver and copper, prove that lue mode of assay applied to them brings out the standard too low ; and further, that the quantity of silver masked or disguised, is not uniform for these different eminent assay masters. An alloy, for example, at the standard of 900 thousandths is judged at M. the Mint of Paris to have a standard of 895-6 At that of Vienna — 898-4 — Madrid — 893-7 ^ Naples — 891-0 The fact thus so clearly made out of a loss in the standard of silver bullion and coin, merits the most serious attention ; and it will appear astonishing, perhaps, that a thing r«:arring every day, should have remained for so long a time in the dark. In reality, however, the fact is not new; as the very numerous and well-made experiments of Tillet, from 1760 to 1763, which are related in the memoirs of the Academy of Sciences, show, in the silver assays, a loss still greater than that which was experienced lately in the laboratory of the Commission of the French Mint. But he thought that, as the error was common to the nations in general, it was not worth while or prudent to introduce any innovation. A mode of assaying, to give, with certainty, the standard ci* silver bullion, should be entirely independent of the variable circumstances of temperature, and the unknown proportions of copper, so difficult to regulate by the mere judgment of the senses. The process by the humid way, recommended by me to the Royal Mint in 1829, and ex- hibited as to its principles before the Right Honorable John Herries, then Master, in 1830, has all the precision and certainty we could wish. It is founded on the well-known property which silver has, when dissolved in nitric acid, to be precipitated in a chloride of silver quite insoluble, by a solution of sea salt, or by muriatic acid ; but, instead of deter- mining the weight of the chloride of silver, which would be somewhat uncertain and rather tedious, on account of the difficulty of dr}ing it, we take the quantity of the solution of sea salt which has been necessary for the precipitation of the silver. To put the process in execution, a liquor is prepared, composed of water and sea salt in such proportions that 1000 measures of this liquor may precipitate, completely, 12 grains of silver, perfectly pure, or of the standard 1000, previously dissolved in nitric acid. The liquor thus prepared, gives, immediately, the true standard of any alloy whatever, of silver and copper, by the weight of it which may be necessary to precipitate 12 grains of this alloy If, for example, 905 measures have been required to precipitate the 12 grains of alloy, its standard would be 905 thousandths. The process by the humid way is, so to speak, independent of the operator. The manipulations are so easy ; and the term of the operation is very distinctly announced by the absence of any sensible nebulosities on the affusion of sea salt into the silver solution, while there remains in it ^ thousandth of metal. The process is not tedious, and in experienced hands it may rival the cupel in rapidity ; it has the advantage over the cupel of being more within the reach of ordinary operators, and of not requiring a long apprenticeship. It is particularly useful to such assayers as have only a few assays to make daily, as it will cost them very little time and expense. By agitating briskly during two minutes, or thereby, the liquid rendered milky by the precipitation of the chloride of silver, it may be sufficiently clarified to enable us to appreciate, after a few moments of repose, the disturbance that can be produced in it by the addition of 1000 of a gram of silver. Filtration is more efficacious than agitation, especially when it is employed afterwards; it may be sometimes used; but agitation, which is much more prompt, is generally sufficient. The presence of lead and copper, or any other melal, except mercury, has n perceptible influence on the quantity of sea salt necessar)' to precipitate the silver ; that is to say, the same quantity of silver, pure or alloyed, requires for its precipitation a constant quantity of the solution of sea ssJt. Supposing that we operate upon a gramme of pure silver, the solution of sea salt ought to be such that 100 centimetres cube may precipitate exactly the whole silver. The standard of an alloy is given by the number of thousandths of solution of sea salt necessary to precipitate the silver contained in a gramme of the alloy. When any mercury is accidentally present, which is, however, a rare occurrence, it is made obvious by the precipitated chloride remaining white when exposed to daylight, whereas when there is no mercury present, it becomes speedily first gray and then purple. Silver so contaminated must be strongly ignited in fusion before being assayed, and its loss of weight noted. In this case, a cupel assay must be had recourse to. Preparation of the Normal SohUioii of Sea Salt, when it is measured by Weight. — Sup- posing the sea salt pure as well as the water, we have only to take these two bodies in the proportion of 0-5427 k. of salt to 99-4573 k. of water, to have 100 k. of solution. i fa V ^ : t,- 100 ASSAY. kep. i„ reserve fofS^f^fi t ^^tj^ ''il'.Zt^lTay'li:^'^ "" « •^». «» ^ the san.e -egree'tf ^ect^n-^rrial^eM^P^^^^^ "^ ""^^ The measure by volume has nnt nil .. ' , . ^ ^'^ "^^" of no correct on. precision, it is more rTpL, and Tque s^^^^^^^^ ^"^' ^^ §™= '' '''^''^^^' mm. This normal solution is ^ made S a v^umn T™''^ ^^^l assays of the of water, or 100 centimetres cube aTa dete^inntl ^"^"^^ ^^ *^'^^ °^ ^^^ grammes one gmmme of silver. The solution nSv^ k?nf ^T^'''^'"""' "^^^ precipitate exactly this case the assay stands in wat orno cLrectlT <^r VhJ?^ temperature, and ii the assay must be corrected accordin<^ to itsTnfluence Th ^"^P^J^t^^e be variable, no change in the principle of the nrocess hni th!! ^^^^ ^'^^ circumstances make some modifications in the apparatus Exd^^^^^ h^! '^^^^'^ i^P^^tant to occasion of applying a correction to l7arMe temSu e ''' "^'"'^'^ ^^^ ^^^^-^^^ - ^-'or We readily obtain a volume of lOO cu^bic centimetres by means of a,.>/., ^, 93 ~* ""^ !? T^l '^"i ^^^" fi"^^ ^-'^^ w^afer up to the mark a, &, and well dried at its point, it wiU ru^ at tC t:r"'^r'"%^®"^' ^^ ?^^es of wa^ at the temperature of 15 C. (59 Fah.). We sav 'Ma Jr Ik ^"^J^*' *^e pipette may still furnish two or f]£ aU6 i^/;j,^-Psofliquid which must not be c^^^^ ^ ^k or reckoned upon. The weight of the volume of he normal solution, taken in this manner ^^^^ suitable precautions, will be uniform from one ha fTt'^o T'\''' "P°" ^^« centio^etres and a hi Hiff ' ' *"; ^^ ^ ^"^'■*^'' c^ a thousandth, and he difference from the n.cun will be obviously twice less, or one half. Let us indicate theS siroTsTa^:^;:^^^ ^ -^-- «^ ^^^ -^ ,•„ l^'^"" ¥''?''^ immersed the beak c of the pipette m the solution we apply suction by the Si' to the upper orifice, and thereby raise the liquW to d, above the circular line a b. We nex aDn r neatly the forefinger of one hand to th?s or'fic/ remove the pipette from the liquid, and iiie It llrT^'Ti ^^.•^^•9^- The'mark aTbeL. placed at the evel of the eye, we make the sur- the plane a b. At the instant it becomes a ^an^enrw'T ^^^^1"'?"^'^ ^ ^^"5^"* to open, by taking away the fin.'er th^t h«rl hp!n ' "^f.^S^^^ ^}'^ beak c of the pipette anything else in the position of the hL^« ^" ?P^'.^^. ^° "' ^^^ ^^^thout changing receive the solution, tEg care to remov^^^^^ V'V^^ ^"^« ^^'^h shSuld If, after filling the pipeiFe bv suctfoTon '^^^'?^^" the efflux has run out. forefinger fast enough to the UDDer'n^ ^"^ «^°"^^ ^"^ a difficulty in applying the the mark a b, he should eLTe' the pf^^^^^^^ ''K'^ ^^ ^own below with his tongue, then apply the middirfinirT^^^ T^ '^' ^°P ^ti" closed after which he may withdraw hiTtnnll ^ a 1"^ f ^'^ ^*"^s to the lower orifice • the orifice previous^wiped Thirrfod^ o? ob'tl^ *'' ^"'^"^^^ °^ ^^^ ^^^^^ ^--^^o ' sea salt is very sitrple, and requires S, comnlex Inn ^^ '"l^'"'^ ^^ "™^^ ««J"tion of manipulation still easier, and^so Lore e^iet ^^^^'^^"^ '- ^^'^^ ^haU indicate another filleVb'y^uXraTdVttS^^ ^^p like a bottle, instead of bein. D'are two sockets separated by a stotco^V Th'/l^ "'P'''^"^'- ^ «"^ receives, by means of a cork stopper l the tuhp V tl- ^^^7 .''"^' ^^PP^'^ interiorly, salt. The lower socket is cemen?e7on^othrw/;^''K *^"''' *^^ ^^^^^ion of sea a screw plug v, which regulates a iTnute opeS "'fy^tin ^T^ V^^b ^'''''^^ ^^ «°^ slowly into the pipettv. Below the s^on-cock ^5 ^^"'^^^ ^o let the air enter verv soldered to the socket, leads the soLttn fnto the Iw IfV°^,^' ?^ "^''^^^ diameter, displaces, to escape by the stopcock K'TheJrfl'^ ^^ *^ r^"^ ^^^ ^^* ^^i^h U replaces the ordin^ screw b- whLh the^pvnf tK.^^^^^ ^'»^ '^^^^ head V, with more or less force, upon Vcontal ^at ^ ^^^ '^'^-'^^ "^^^ *>« ^^^ to pres. 1 ASSAY. 101 Fig. 96 represents, in a side view, the apparatus just described. We here remark an air-cock r, and an opening m. At the extremity Q of the same figure, the conical pipe T enters, with friction. It is by this pipe that the air is sucked into the pipette when it is to be filled from its beak. ^ -v .i v The pipette is supported by two horizontal arms h k (fig. 97) moveable about a common axis a a, and capable of being drawn out or shortened by the aid of two longitu- dinal slits. They are fixed steadily by two screw nuts e e, and their distance may be varied by means of round bits of wood or cork inter- posed, or even by opposite screw nuts o 6. The upper arm h is pierced with a hole, in which is fixed, by the pressure of a wooden screw r, the socket of the pipette. The corresponding hole of the lower arm is larger ; and the beak of the pipette is supported in it by a cork stop- per L. The apparatus is fixed by its tail-piece p, by means of a screw, to the corner of a wall, or any other prop. The manner of filling the pipette is very sim- ple. We begin by applying the fore-finger of the left hand to the lower aperture c ; we then open the two stop-cocks r and r'. Whenever the liquor approaches the neck of the pipette, we must temper its influx, and when it has arrived at some millimetres above the mark a 6, we close the two stop-cocks, and remove our fore-finger. We have now nothing more to do than to regu- late the pipette; for which purpose the liquid must touch the line a b, and must simply adhere externally to the beak of the pipette. This last circumstance is easUy adjusted. After taking away the finger which closed the aperture c of the pipette, we apply to this orifice a moist sponge m,fig. 88, wrapped up in a linen rag, to absorb the superfluous liquor as it drops out. This sponge is called the handkerchief (mott- choir), by M. Gay Lussac. The pipette is said to be wiped when there is no liquor adhering to its point exteriorly. For the convenience of operat- ing, the handkerchief is fixed by friction in a tube of tin plate, ter- minated by a cup, open at bottom to let the droppings flow off into the cistern c, to which the tube is soldered. It may be easily re- moved for the purpose of washing it ; and, if necessary, a little wedge of wood, 0, can raise it toward the pipette. To complete the adjustment of the pipette, the liquid must be made merely to descend to the mark a, b. With this view, and while the handkerchief is applied to the beak o the pipette, the air must be allowed to enter very slowly by unscrewing the plug v, fig. 95; and at the moment of the contact the handkerchief must be removed, and the bottle r, destined to receive the solution, must be placed below the orifice of the pipette, fig. 98. As the motion must be made rapidly, and without hesitation, the bottle is placed .n a cylinder of tin-plate, of a diameter somewhat greater, and forming one body with the cistern and the handkerchief. The whole of this apparatus has for a basis a plate of tinned iron, moveable between two wooden rulers r r, one of which bears a groove, under which the edge of the plate slips. Its traverses are fixed by two abutments b b, placed so that when it is stopped by one of them, the beak of the pipette corresponds to the centre of the neck of the bottle, or is a tangent to the handkerchief. This arrangement, very convenient for wiping the pipette and emptying it, gives the apparatus sufficient solidity, and allows of its being taken away and replaced without deranging anything. It is obvious that it is of advantage, when once the entry of the air into the pipette has been regulated by the screw v, to leave it constantly open, because the I, ' 102 ASSAY. I 1 I motion frora the handterchief to the bottle is performed with sufficient rapidity to prevent a drop of the solution from collecting and falling down. Temperature of the Solution. — After having described the manner of measuring by vcflume the normal solution of the sea salt, we shall indicate the most conv(;nient means of taking the temperature. The thermometer is placed in a tube of glass t, Jig. 89, which the solution traverses to arrive at the pipette. It is suspended in it by a piece of cork, grooved on the four sides to afford passage to the liquid. The scale is engraved upon the tube itself, and is repeated at the opposite side, to fix the eye by the coincidence of this double division at the level of the thermometric column. The tube is joined below to another narrower one, through which it is attached by,means of a cork stopper B, in the socket of the stop-cock of the pipette. At its upper part it is cemented into a brass socket, screw-tapped in the inside, which is connected in its turn by a cock, with the extremity, also tapped, of the tube above t, belonging to the reservoir of the normal solution. The corks employed here as connecting links between the parts of the apparatus, give them a certain flexibility, and allow of their being dismounted and re- mounted in a very short time ; but it is indispensable to make them be traversed by a hollow tube of glass or metal, which will hinder them from being crushed by the pressure they are exposed to. If the precaution be taken to grease them with a little suet, and to fill their pores, they will suffer nO leakage. Preservation of the Normal Solution of Sea Salt in metallic Vessels. — M. Gay Lussac uses for this purpose a cylindrical vessel or drum of copper, of a capacity of about 1 10 litres, having its inside covered with a rosin and wax cement. Preparation of the Normal Solution of Sea Salt, measuring it by Volume. — If the drum contains 1 10 litres, we should put only 105 into it, in order that sufficient space may be left for agitating the liquor without throwing it out. According to the principle that 100 centimetres cube, or JL of a litre of the solution should contain enough of sea salt to precipitate a gramme of pure silver ; and, admitting, moreover, 13*516 for the prime equi- valent of silver, and 7*335 for that of sea salt, we shall find the quantity of pure salt that should be dissolved in the 105 litres of water, and which corresponds to 105 X 10 = 1050 grammes of silver, to be by the following proportion : — 13*516 : 7-335 :*. 1050 gramra. : x=569-83 gr. And as the solution of the sea salt of commerce, formerly mentioned, contains approxi- mately 250 grammes per kilogramme, we must take 2279*3 grammes of this solution to have 569*83 gram, of sail. The mixture being perfectly made, the tubes and the pipeti* must be several times washed by running the solution through them, and putting it into the drum. The standard of the solution must be determined after it has been well agi- tated, supposing the temperature to remain uniform. To arrive more conveniently at this result, we begin by preparing two decimes solu- tions ; one of silver, and another of sea salt. The decime solution of silver is obtained by dissolving 1 gramme of silver in nitric acid, and diluting the solution with water till its volume becomes a litre. The decime solution of sea salt may be obtained by dissolving 0*543 grammes of pure sea salt in water, so that the solution shall occupy a litre ; but we shall prepare it even with the normal solution which we wish to test, by mixing a measure of it with 9 mea- sures of water ; it being understood that this solution is not rigorously equivalent to that of silver, and that it will become so, only when the normal solution employed for its pre- paration shall be finally of the true standard. Lastly, we prepare beforehand several stoppered vials, in each of which we dissolve 1 gramme of silver in 8 or 10 grammes of nitric acid. For brevity's sake we shall call these tests. Now to investigate the standard of the normal solution, we must transfer a pipette of it into one of these test vials ; and we must agitate the liquors briskly to clarify them. After some instants of repose, we must pour in 2 thousandths of the decime solution ol sea salt, which, we suppose, will produce a precipitate. The normal liquor is conse- quently too feeble ; and we should expect this, since the sea salt employed was not per- fectly pure. We agitate and add 2 fresh thousandths, which will also produce a precipi- tate. We continue thus by successive additions of 2 thousandths, till the last produces no precipitation. Suppose that we have added 16 thousandths : the last two should not be reckoned, as they produced no precipitate ; the preceding two were necessary, but only in part ; that is to say, the useful thousandths added are above 12 and below 14, or otherwise they are on an average equal to 13. Thus, in the condition of the normal solution, we require 1013 parts of it to pre- cipitate one gramme of silver, while we should require only 1000. We shall find the quantity of concentrated solution of sea salt that we should add, by noting that the quantity of solution of sea salt, at first employed, viz. 2279*3 grammes, produced a standard of only 987 thousandths=1000 — 13; and by using the following proportion: 987 : 2279*3 :: 13 : x=30'02 grammes. ASSAY. 108 This quantity of the strong solution of salt, mixed with the norma* solation in the dram, will correct its standard, and we shall now see by how much. After having washed the tubes and the pipette with the new solTition, we mtrat repeat the experiment upon a fres-h gramme of silver. We shall find, for example, in proceedinsr only by a thousandth at a time, that the first causes a precipitate, but not the second. The standard of the solution is still too weak, and is comprised between 1000 and 1001 ; that is to say, it may be equal to 1000|, but we must make a closer approxi- mation. We pour into the test bottle 2 thousandths of the decime solution of silver, which will destroy, perceptibly, two thousandths of sea salt, and the operation will have retrograded by two thousandths ; that is to say, it will be brought back to the point at which it was first of all. If, after having cleared up the liquor,, we add half a thousandth of the de- eime solution, there will necessarily be a precipitate, as we knew beforehand, but a se- cond will cause no turbidity. The standard of the normal liquor will be consequently comprehended between 1000 and 1000|, or equal to lOOOj. We should rest content with this standard, but if we wish to correct it, we may remark that the two quantities of solution of salt added, viz. 2279*3 gr. -j- 3002 gr.= 2309*32 gr. have produced only 999*75 thousandths, and that we must add a new quantity of it corresponding to ^ of a thousandth. We make, therefore, the proportion 999*75 : 2309*32 :: 0*26 : x. But since the first term differs very little from 1000, we may content ourselves to have X by taking the \'A^ of 2309*32, and we shall find 0*577 gr. for the quantity of solution of sea salt to be added to the normal solution. It is not convenient to take exactly so small a quantity of solution of sea salt by the balance, but we shall succeed easily by the following process. We weigh 50 grammes of this solution, and we dilute it with water ; so that it occupies exactly half a litre, or 600 centimetres cube. A pipette of this solution, one centimetre cube in volume, will give a decigramme of the primitive solution, and as such a small pipette is divided into twenty drops, each drop, for example, will represent 5 milligrammes of the solution. We should arrive at quantities smaller still by diluting the solution with a proper quantity of water ; but greater precision would be entirely needless. The testing of the normal liquor just described, is, in reality, less tedious than might be supposed. It deserves also to be remarked, that liquor has been prepared for more than 1000 assays ; and that, in preparing a fresh quantity, we shall obtain directly its true standard, or nearly so, if we bear in mind the quantities of water and solution of salt which had been employed. Correction of the Standard of the Normal Solution of Sea Salt, when the Temper aturt changes. — We have supposed, in determining the standard of the normal solution of sea salt, that the temperature remained uniform. The assays made in such circumstances, have no need of correction ; but if the temperature should change, the same measure of the solution will not contain the same quantity of sea salt. Supposing that we have tested the solution of the salt at the temperature of 15° C. ; if, at the time of making the experiment, the temperature is 18° C, for example, the solution will be too weak on ac- count of its expansion, and the pipette will contain less of it by weight ; if, on the con- trary, the temperature has fallen to 12°, the solution will be thereby concentrated and will prove too strong. It is therefore proper to determine the correction necessary to be made, for any variation of temperature. To ascertain this point, the temperature of the solution of sea salt was made succes- sively to be a», 5°, 10°, 15°, 20°, 25°, and 30° C. ; and three pipettes of the solution were weighed exactly at each of these temperatures. The third of these weighings gave the mean Aveight of a pipette. The corresponding weights Of a pipette of the solution, were afterwards graphically interpolated from degree to degree. These weights form the se- cond column of the following table, entitled, Table of Correction for the Variations in the Temperature of the Normal Solution of the Sea Salt. They enable us to correct any tem- perature between and 30 degrees centigrade (32P and 86° Fahr.) when the solution of sea «;alt has been prepared in the same limits. Let us suppose, for example, that the solution has been made standard at 15°, and that, at the time of using it, the temperature has become 18°. We see by the second column of the table, that the weight of a measure of the solution is 100*099 gr. at 15°, and 100*065 at 18°; the difference 0*034 gr., is the quantity of solution less which has been really taken ; and of course we must add it to the normal measure, in order to make it equal to one thousand milliemes. If the temperature of the solution had fallen to 10 degrees, the difference of the weight of a measure from 10 to 15 degrees would be 0*019 gr., which we must on the contrary deduct from the measure, since it had been taken too large. These differences of weight of a measure of solution at 15**, from that of a J r I 104 ASSAY. measure at any other temperature, form the column 15° of the table whprp th^v •«. expressed m thousandths; they are inscribed on the same horizontal linT.S thftem peratures to which each of them relates, with the sign + plus, when hey must blL?S' and with the sign _ minus, when they must be subtraTte^d. The c lumns 5' ^V 2^.' 25 , 3o°, have been calculated in the same manner for the cases in wh Jrh th/ nArl 1 so uuon may have been graduated to each of these temperatt^es Thus to calLa^^^^^^^ column 10, the number 100-118 has been taken of the column of weights ?or a 1.^ Xt!''' '"' ''' ^^^^"'^ '"" ""'' ''' "^^^^« '' ^^" sa^tTuSn \T^fn Table of Correction for the Variations in iLt Temperatiire of the Normal Solution of the Sea Salt. Temperature. 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Weight. I eram. 100,109 100,113 100,115 110,118 100,120 100,120 100,118 100,116 100,114 100,110 100,106 100,099 100,090 100,078 100,065 100,053 100,039 100,021 100,001 99,983 99,964 99,944 99,924 99,902 99,879 99,858 99,836 mill. 00 0-0 0-0 4-0-1 — 0-1 --01 — 0-1 0-0 0-0 0-0 — 0-1 — 0-1 --0-2 — 0-4 — 0-5 — 0-6 — 0-7 — 0-9 — 1-1 — 1-3 — 1-5 — 1-7 — 1-9 — 2-1 — 2-3 — 2-6 — 2-8 10° mill. — 0-1 — 0-1 0-0 0-0 0-0 0-0 0-0 0-0 0-0 — 0-1 — 0-1 — 0-2 — 0-3 — 0-4 — 0-5 — 0-7 — 0-8 — 1-0 — 1-2 — 1-4 — 1-5 — 1-7 — 1-9 — 2-2 — 2-4 — 2-6 — 2-8 15° 20= 25° t mill. — 0-1 --0-1 --0-2 --0-2 --0-2 --0-2 --0-2 --0-2 --0-2 0-1 0-1 — 0-0 — 0-1 — 0-2 — 0-3 — 0-5 — 0-6 — 0-8 — 1-0 — 1-2 — 1-4 — 1-6 — 1-8 — 2-0 — 2-2 — 2-4 — 2-6 mill. --0-7 --0-7 --0-8 0-8 -r 0-8 + 0-8 — 08 --0-8 --0-8 --0-7 --0-7 --0-6 --0-5 — 0-4 — 0-3 — 0-1 00 — 0-2 -.0-4 — 0-6 — 0-8 — 1-0 — 1-2 — 1-4 — 1-6 — 1-8 — 2-0 mill. 1-7 1-7 — 1-7 -- 1-7 --1-8 — 1-8 --1-7 — 1-7 --1- — 1- 7 7 1-6 1-6 --1-5 — 1-3 — 1-2 -- M --10 --0-8 --0-6 --0-4 -f 0-2 0-0 — 0-2 — 0-4 — 0-7 — 0-9 — M 30«» mifl. -j-2-7 --2-8 — 2-8 --2-8 --2-8 --2-8 --2-8 --2-8 2-8 2-7 -I-2-7 --2-6 --2-5 --2-4 2-3 2-2 --2-0 --1-9 -f 1.7 -I-1-5 — 1-3 --M --0-9 --0-7 --0-4 --0-2 0-0 the^srolacrtwlu f ^,^^" ^"^P^^^^ *« facilitate and abridge the manipulations. In thl .™ w ^ I J Hi?'' ^^'^'"f. "' assaying the specimens of silver should all be of ^^nnZtj ^""^ • ^ t^ "^^ ^'^^^''' They should be numbered at their top, as well ^e llL o7r'' '"^ '^^ -'^l' ^ 2' ?' ^'' They may be ranged successively n teTs lilfE f ^ .>f '^f ^ 'T'' ?"'"" P^^'«^ ^'^ « «»PP«rt in their proper order. Each two ments dul^C wV"^^^^^^^ ^^""'^ ^". " ^'"^'""^^ ^'^ ^^^^ (•^^^- ^ ^^)' ^^'^ ^en comply? SJ.tfi^^u«.These compartments are cut out anteriorly to about half their height, to a ow the bottoms of the bottles to be seen. AVhen each vial has received iS ^Im2fn?^lT•'''''•7^^''^^•1^^^^^^ °^"^t be poured into it a^St S grammes of nitric acid of specific gravity 1-28, with a pipette, containing that quant tv- illov ThP^'f VX'^'""' t^ ^"^^^ ^^^^' ^'^ order to facilitate the LluUon of tJ^ fi2' IthJT^ VTZ^^''^^''^''^^ "^^^^ «f ti" plate, intended to receive the ve^t^ne the viak h.in?i' 1'"^^' bottom, pierced with smaU holes, for the purpose of pre- lZ\n tZI^T^ '^'^^"J ^' It msulates them from the bottom to which Uie heat is rotetarriId'ruX\"cSneV.^"'' ^"" '' ^""'^ "^""^ ^^^" ^^ ^'""'^"^^' " ^"»^^^ ]pn^\'pof /'''r'~^-°^'^^\^'T' ^ s^ffic'e"t'y ^^act idea of it, and may dispense with a Thfvtl! J'''tT''";\-^' has ten cylindrical compartmenis, numbered from 1 to lo! thP An J f f^ 'I ^^" ?'^^^^. "^^'"^ ^^^^^ «f the pipette, intended to measure put Eacrrthlril ''!S "'^^r/^'V ^"^ ^ ^P'^^' *""" «f this'^solution is put in each v?al fir<^? ; t^ ^}?^^c Z'^^ '*' ^'a^,stoPP^'-» previously dipped in pure water. They are fixed in the cells of Uie agitator by wooden wedges. The agititor is then susjinded > ASSAY. 10& to a spring R, and, seizing it with the two hands, the operator gives an aiiemating rapid uiovcn,ent, which agitates the solution, and makes it, in less than a minute, as limpid as water. This movement is promoted by a spiral spring, E, fixed to the agitator and the ground, but this is seldom made use of, be- cause it is convenient to be able 10 transport the agitator from one place to another. When the agitation is finished, the wedges are to be taken out, and the vials are placed in order upon a table furnished with round cells destined to receive them, and to screen them from too free a light. When we place the vials upon this table, we must give them a brisk cir- cular motion, to collect the chloride of silver scattered round their sides ; we must lift out their stoppers, and suspend them in wire rings, or pincers. We next pour a thousandth of the decime solution into each vial; and before this operation is terminated, there is formed in the first vials, when there should be a precipitate, a nebulous stratum, very well marked, of about a centimetre in thickness. At the back of the table there is a black board divided into compart- ments numbered from 1 to 10, upon each of which we mark, wiih chalk, the thousandths of the decime liquor put into the correspondent vial. The thousandths of sea salt, which indicate an augmentation of standard, are pre- ceded by the sign -{-, and the thou- sandihs of nitrate of silver by the sign — . When the assays are finished, the liquor of each vial is to be poured into a large vessel, in which a slight excess of sea salt is kept ; and when it is full, the supernatant clear liquid must be run oflf with a syphon. The chloride of silver may be reduced without any perceptible loss. After having washed it well, we immerse pieces of iron or zinc into it, and add sulphuric acid in suffi- cient quantity to keep up a feeble disengagement of hydrogen gas. The mass must not be touched. In a few days the silver is completely reduced. This is easily recognised by the color and nature of the product ; or by treating a small quantity of it with water of ammonia, we shall see whether there be any chloride unreduced ; for it will be dissolved by the ammonia, and will afterwards appear upon saturating the ammonia with an acid. The chlorine remains associated with the iron or the zinc in a state of solution. The first washings of the reduced silver must be made with an acidulous water, to dissolve the oxyde of iron which may have been formed, and the other washings with common water. After decanting the water of the last washing, we dry the mass, and add a little powdered borax to it. It must be now fused. The silver being in a bulky powder, is to be put in successive portions into a crucible as it sinks down. The heat should be at first moderate ; but towards the end of the operation it must be pretty strong to bring into complete fusion the silver and the scoriae, and to efl'ect their complete separation. In case it should be supposed t^jat the whole of the silver had not been reduced by the iron or zinc, a little carbonate of potash should be added to the borax. The silver may also be reduced by exposing the chloride to a strong heat, in contact with chalk and charcoal. The following remarks by M. Gay Lussac, the author of the above method, upon the efltct of a little mercury in the humid assay, are important : — It is well known that chloride of silver blackens the more readily as it is exposed to an intense light, and that even in the diffused light of a room, it becomes soon sensibly colored. If it contains four to five thousandths of mercury, it does not blacken ; It remains of a dead white : with three thousandths of mercury, there is no marked discoloring in diflfused light ; with two thousandths it is slight ; with one it is much more marked, but still it is much less intense than with pure chloride. With half a n 106 ASSAY. ASSAY. 107 thousandth of mercury the difference of color is not remarkable, and is perceived onlj in a very moderate light. But when the quantity of mercury is so small that it cannot be detected by the difference of color in the chloride of silver, it may be rendered quite evident by a very simple process of concentration. Dissolve one gramme of the silver supposed to contain I of a thousandth of mercury, and let only J of it be precipitated, by adding only J of the common sail necessary to precipitate it entirely. In thus operating, the | thou- sandth of mercury is concentrated in a quantity of chloride of silver four times smaller : it is as if the silver having been entirely precipitated, four times as much mercury, equal to two thousandths, had been precipitated with it. In taking two grammes of silver, and precipitating only \ by common salt, the precipitate would be, with respect to the chloride of silver, as if it amounted to four thousandths. By this process, which occupies only five minutes, because exact weighing is not necessary, J- of a thousandth of mercury may be detected in silver. It is not useless to observe, that in making those experiments the most exact manner of introducing small quantities of mercury into a solution of silver, is to weigh a minute globule of mercury, and to dissolve it in nitric acid, diluting the solution so thnt it may contain as many cubic centimetres as the globule weighs of centigrammes. Each cubic centimetre, taken by means of a pipette, will contain one milligramme of mercury. If the ingot of silver to be assayed is found to contain a greater quantity of mercury, one thousandth for example, the humid process ought either to be given up in this case, or to be compared with cupellation. When the silver contains mercury, the solution from which the mixed chlorides are precipitated does not readily become clear. Silver containing mercury, put into a small crucible and mixed with lamp-black, to prevent the volatilization of the silver, was heated for three quarters of an hour in a muffle, but the silver increased sensibly in weight. This process for separating the mercury, therefore, failed. It is to be observed, that mercury is the only metal which has thus the power of disturbing the analysis by the humid way. Assaying of Gold. — In estimating or expressing the fineness of gold, the whole mass spoken of is supposed to weigh 24 carats of 12 grains each, either real, or merely proportional, like the assayer's weights ; and the pure gold is called fine. Thus, if gold be said to be 23 carats fine, it is to be understood, that in a mass, weighing 24 carats, the quantity of pure gold amounts to 23 carats. lu such small werk as cannot be assayed by scraping off a part and cupelling it, the assayers endeavor to ascertain its fineness or quality by the touch. This is a method of comparmg the color and other properties, of a minute portion of the metal, with those of small bars, the composition of which is known. These bars are called touch needles, and they are rubbed upon a smooth piece of black basaltes or pottery, which, for this reason, is called the touchstone. Black flint slate will serve the same purpose. Sets of gold needles may consist of pure gold ; of pure gold, 23^ carats with | carat of silver ; 23 carats of gold with one carat of silver ; 22| carats of gold with 1| carat of silver ; and so on, till the silver amounts to four carats ; after which the additions may proceed by whole carats. Other needles may be made in the same manner, with copper instead of silver ; and other sets may have the addition, consisting either of equal parts of silver and copper, or of such proportions as the occasions of business require. The examination by the touch may be advantageously employed previous to quartation, to indicate the quantity of silver necessary to be added. In foreign countries, where trinkets and small work are required to be submitted to the assay of the touch, a variety of needles is necessary ; but they are not much used in England. They afford, however, a degree of information which is more considerable than might at first be expected. The attentive assayer compares not only the color of the stroke made upon the touchstone by the metal under examination, with that produced by his needle, but will likewise attend to the sensation of roughness, dryness, smooth- ness, or greasiness, which the texture of the rubbed metal excites, when abraded by the stone. When two strokes perfectly alike in color are made upon the stone, he may then wet them with aquafortis, which will affect them very differently, if they be not similar compositions ; or the stone itself may be made red-hot by the fire, or by the blow- pipe, if thin black pottery be used ; in which case the phenomena of oxydation will differ according to the nniure and quantity of the alloy. Six principal circumstances appear to affect the operation of parting ; namely, the quantity of acid used in parting, or in the first boiling ; the concentration of this acid ; the time employed in its application ; the quantity of acid made use of in the reprise, or second operation ; its concentration ; and the time during which it is applied. From experiment it has been shown, tnat each of these unfavorable circumstances might easily occasion a loss of from the half of I a thirty -second part of a carat, to two thirty-second parts. The assayers explain their technical language by observing, that in the whole mass consisting of twenty -four carats, this thirty-second part denotes l-768th part of the mass. It may easily be conceived, therefore, that if the whole six circumstances were to exist, and be productive of errors, falling the same way, the loss would be very considerable. It is therefor^ indispensably necessary, that one uniform process should be followed in the assays of gold ; and it is a matter of astonishment, that such an accurate process should not have been prescribed by government for assayers, in an operation of such great commercial importance, instead of every one being left to follow his own judgment. The process recommended ki the old French official report is as follows : — twelve grains of the gold intended to be assayed must be mixed with thirty grains of fine silver, and cupelled with 108 grains of lead. The cupellation must be carefully attended to, and all the imperfect buttons rejected. When the cupellation is ended, the button must be reduced, by lamination, into a plate of 1| inches, or rather more, in length, and four or five lines in breadth. This must be rolled up upon a quill, and placed in a matrass capable of holding about three ounces of liquid, when filled up to its narrow part. Two ounces and a half of very pure aquafortis, of the strength of 20 degrees of Baume's areometer, must then be poured upon it ; and the matrass being placed upon hot ashes, or sand, the acid must be kept gently boiling for a quarter of an hour : the acid must then be cautiously decanted, and an additional quantity of 1| ounces must be poured upon the metal, and slightly boiled for twelve minutes. This being likewise carefully decanted, the small spiral piece of metal must be washed with filtered river water, or distilled water, by filling the matrass with this fluid. The vessel is then to be reversed, by applying the extremity of its neck against the bottom of a crucible of fine earth, the internal surface of which is very smooth. The annealing must now be made, after having separated the portion of water which had fallen into the crucible ; and, lastly, the annealed gol(^ must be weighed. For the certainty of this operation, two assays must be made in the same manner,* together with a third as- say upon gold of twenty-four carats, or upon gold the fineness of which is perfectly and generally known. No conclusion must be drawn from this assay, unless the latter gold should prove to be of the fineness of twenty-four carats exactly, or of its known degree of fineness; for. if there be either loss or surplus, it may be inferred that the other two assays, having undergone the same operation, must be subject to the same error. The operation being made according to this process by several assayers, in circumstances of importance, such as those which relate to large fabrications, the fineness of the gold must not be depended upon, nor considered as accurately known, unless all the assayers have obtained a uni- form result, without communication with each other. This identity must be considered as referring to the accuracy of half the thirty-second part of a carat. For, notwithstanding every possible precaution or uniformity, it very seldom happens that an absolute agree- ment is obtained between the different assays of one and the same ingot; because the ingot itself may differ in its fineness in different parts of its mass. The phenomena of the cupellation of gold are the same as of silver, only the ope- ration is less delicate", for no gold is lost by evaporation or penetration into the bone- ash, and therefore it bears safely the highest heat of the assay furnace. The button of gold never vegetates, and need not therefore be drawn out to the front of the muffle, but may be left at the further end till the assay is complete. Copper is retained more strongly by gold than it is by silver; so that with it 16 parts of lead are requisite to sweat out 1 of copper ; or, in general, twice as much lead must be taken for the copper alloys of gold, as for those of silver. When the copper is alloyed with very small quan- tities of gold, cupellation would afford very uncertain results; we must then have re- course to liquid analysis. M. Vauquelin recommends to boil 60 parts of nitric acid at 22* Baume, on the spiral slip or cornet of gold and silver alloy, for twenty-five minutes, and replace the Ikjuid afterwards by acid of 32°, which must be boiled on it for eight minutes. This process is free from uncertainty when the assay is performed upon an alloy containing a con- siderable quantity of copper. But this is not the case in assaying finer gold ; for then a little silver always remains in the gold. The surcharge which occurs here is 2 or 3 thousandths ; this is too much, and it is an intolerable error when it becomes greater, which often happens. This evil may be completely avoided by employing the following process of M. Chaudet. He takes 0*500 of the fine gold to be assayed ; cupels it with 1*500 of silver, and 1-000 of lead; forms, with the button from the cupel, a riband or strip three inches long, which he rolls into a comet. He puts this into a matrass with acid at 22° B., which he boils for 3 or 4 minutes. He replaces this by acid of 32° B., and boils for ten minutes; then decants off, and boils again with acid of 32°, which must be finally boiled for 8 or 10 minutes. Gold thus treated is very pure. He washes the comet, and puts it entire into a small I ! ! I I i i I w 108 AUTOMATIC. f^'l^Il P™^^^? to water ; heats the crucible to duU redness under the muffle whr^n cuW property of platinum; when alloyed with silver, it becomes soluble nnitrLac^d Therefore by a proper quartation of the alloy by cupellation, and boiling the bu ton w th nitric acid, we may get a residuum of pure gold. If we were to treat the h.mnn Z-fV^ sulphuric acid, however, we should dissolve nothing but the sTlver. Se copperTer^^^^ removed by cupellation Hence, supposing that we have a quaternary coSnd of con^ denotes the copper. This button, treated by sulphuric add, will suffer a losrof welS equal to the amount of silver present. The residuum, by quartation with silver anTtoS ing with nitric acid, will part with its platinum, and the gold wSl remaTpure For" more detailed explanations, see Platinum remain pure. Uor ohiiTfn^"? WEIGHTS OK ATOMS, are the primal quantities in which the different ejects of chemistry, simple or compound, combine with each other, referred to a common ^,hP ct ?' rr^' ^•'^^^"" ^ ^'^'^'"^^ ^y ««^« philosophers, and hX4n by oZrs ^,«;„t.i^ .I'i'^^ comparison. Every chemical maniifacturer should be ifroulhir quamted with the combinmg ratios, which are, for the same two substences noronlv defi n te, but multiple; two great truths, upon which are founded not merdy the rL^onal of h.s operations, but also the means of modifying them to useful our nolLTtlT^ nijh! Khi^i 't? y^S^table alkali extracted from the Atropa belladonna, or deadly night-shade. It is composed of about YO-98 carbon 1-fi'iU'^^f.JZ a.qo ^^*^^^X 10-36 oxygen in 100 parfs. It is prepared by t,S^hoeX^^^^^^^^ ^lZ\Z T"'"?' '^"'."f of "'.^''■•y. with eauitic sodatmto sligE kallne reac on a^d k token ni hi 5h.°"/'.,""\*l""'"° "."<■ " '.'"If """^s its voIuL of ether The atC"a h,(T.il7t^ !•"■' ^^i "«"'" dopo'it'd f'om it when the elhereous solution U ™Mt. tni h" T* -'T ^'"^ »'•««*■"'"■* with ether is repeated upon the S prec^ ^ ACTAR OF Rm?-'5 TT PT ^"""' P?"^'"' "^ prcseribid. ^ iTTTmvrlSrrJv^r^?;. ®««0"?' Volatile, and Perfumery AUTOM 4Tir i t™- kT'? f '^' " ?'■??«'•■"'»» »f tin ; ,.hieh see. tne McisMtude of language, it has now come to signify every extensive nroduPt of art which 18 made by machinery, with little or no aid of the human hand srthat th. most perfect manufacture is that which dispenses entirely withZnua^Lor^It^8 m our modern cotton and flax mills that automatic opei4ons aTe dtplaved^ mo t advantage; for there the elemental powers have been made to aniSe milHornf complex organs, imparting to forms W wood, iron and bmss! an iSofenT iracv Us noVe'rcreat^^^^^^^ masterpieces, so may the philosophy of manufactures in these The constant aim and effect of these automatic improvements in the arts are nhilnn thropic, as they tend to relieve the workman either from niches of adiltmrtwr^^^^ rn"rt"htt^^^^ T' ""' 'T p^"''"' .-petitir:ftffot whS^^^^^^^^^^^^ work neon^e ad ^U I"^ ' arranged power-mill combines the opemtion of many work people, adult and young, in tending with ass duoiis skill a svsteni of nrodnotivi machines continuously Impelled by a central force. How vastly condlh^^^ commercial greatness of a nation, and the comforts of mankind irumanndusti^ can n^tre'fittunTo "^'- ^'Tf'T^ '"^ '\' ^^^"^^^ '^ muscular^ZTwh^h s b^fu nature fitliil and capricious, but when made to consist in the task of guiding the work bvTomeTnll^^^^^^^ "l^ •"? ''^''}'^^ ^"P^^^^^^' ^^^^ ^^"^^ precision aifdvei^-it;, by some ndefatigable physica agent, is apparent to every visitor of our cotton flax silk, wool, and machine factories. This great era in the useful urts is mainly due t^ the genius of Ark w right Prior to the introduction of his system, manufactures were every where feeble and fluctuating in their development, shooting forth luxuHanlTfor ^^ .T;/"! ^^''"'^ withering almost to the roots like annual plants. TheirTerennial growth then began, and attracted capital, in copious streams, to irrigate the r clfrmak. Philosophy of Manufkctures, p. 1. t Ibid., p. 2. ' AUTOMATON. 109 of industry. When this new career commenced, about the year 1770, the annual consumption of cotton in British manufactures was under four millions of pounds' weight, and that of the whole of Christendom was probably not more than ten millions. In 1850 the consumption in Great Britain and Ireland was about five hundred and eighty-eight millions of pounds, and that of Europe and the United States together one thousand and ninety-two millions. In our spacious factory apartments the benignant power of steam summons around him his myriads of willing menials, and assigns to each the regulated task, substituting for painful muscular effort upon their part, the energies of his own gigantic arm, and demanding in return, only attention and dexterity to cor- rect such little aberrations as casually occur in his workmanship. Under his auspices and in obedience to Arkwright's polity, magnificent edifices, surpassing far in number, value, usefulness, and ingenuity of construction, the boasted monuments of Asiatic, Egyptian, and Roman despotism, have, within the short period of fifly years, risen up in this kingdom, to show to what extent capital, industrj', and science, may augment the resources of a state, while they meliorate the condition of its citizens. Such is the automatic system, replete with prodigies in mechanics and political economy, which promises, in its future growth, to become the great minister of civilization to the ter- raqueous globe, enabling this country, as its heart, to diffuse, along with its commerce, the life-blood of knowledge and religion to myriads of people still lying " in the region and shadow of death."* Of these truths, the present work affords decisive evidence in almost every page. AUTOMATON. In the etymological sense, this word (self-working) signifies every mechanical construction which, by virtue of a latent intrinsic force, not obvious to com- mon eyes, can carry on, for some time, certain movements more or less resembling the results of animal exertion, without the aid of external impulse. In this respect, all kinds of clocks and watches, planetariums, common and smoke jacks, with a vast number of the machines now employed in our cotton, silk, flax, and wool factories, as well as in our dyeing and calico printing works, may be denominated automatic. But the term, auto- maton, is, in common language, ajxpropriated to that class of mechanical artifices in which the purposely concealed power is made to imit,ate the arbitrary or voluntary motions of living beings. Human figures, of this kind, are sometimes styled Androidcsy from the Greek term, like a man. Although, from what we have said, clock-work is not properly placed under the head automaton, it cannot be doubted that the art of making clocks, in its prosressive improvement and extension, has given rise to the production of automata. The most of these, in their interior structure, as well as in the mode of applying the moving power, have a distinct analogy with clocks ; and these automata are frequently mounted in connexion with watch work. Towards the end of the 13th century, several tower clocks, such as those at Strasburg, Lubec, Prague, Olmutz, had curious mechanisms attached to them. The most careful historical inquiry proves that automata, properly speaking, are certainly not older than irftceZ-clocks ; and that the more perfect struc- tures of this kind are subsequent to the general introduction of sjortwg-clocks. Many accounts of ancient automata, such as the flying doves of Archytas of Tarenlum*. Regiomontanus's iron flies, the eagle which flew towards the emperor Maximilian, iii Nuremburg, in the year 1470, were deceptions, or exaggerated statements; for, three such masterpieces of art would form now, with every aid of our improved mechanisms, the most difficult of problems. The imitation of flying creatures is extremely diflicult, for several reasons. There is very little space for the moving power, and the only ma- terial possessed of requisite strength being metal, must have considerable wcicrht. Two automata, of the celebrated French mechanician, Vaucauson, first exhibited in the year 1738, have been greatly admired ; namely, a flute-player, five and a half feet high, with its cubical pedestal, which played several airs upon the German flute ; and that, not by any interior tube-work, but through the actual blowing of air into the flute, the motion of the tongue, and the skilful stopping of the holes with the fingers ; as also a duck, which imitated many motions of a natural kind in the most extraordinary manner. This artist has had many imitators, of whom the brothers Droz of Chaux de Fonds were the most distinguished. Several very beautiful clock mechanisms of theirs are known. One of them with a figure which draws; another playing on the piano; a third which writes, besides numerous other combined automata. Frederick Von Knauss completed a writing machine at Vienna, in the year 1760. It is now in the model cabinet of the Polytechnic Institute, and consists of a globe 2 feet in diameter, con- taining the mechanism, upon which a figure 7 inches high sits, and writes upon a sheet of paper fixed to a frame, whatever has been placed beforehand upon a regulating cy- linder. At the end of every line, it rises and moves its hand sideways, in order to begin a new line. Very complete automata have not been made of late years, because they are very * Philosophy of Manufactures, p. 18 110 AUTOMATON. h ii 1 I expensive; and by soon satisfying curiosity, they cease to interest Ino-^nlnn- «,^ cl.,nic,ans find themselves betir ?ewarded%di7ecting their Xts to t^^^^^^^^^^ Fr^n Ph I f 1 T ^ Vienna, and a similar work of KaufFmann, at Dresden In Httri ^T^"'*^"u ''''"•^ ""^^''^ "^°^'""" *« °^«^« "^i""te automata which exci'te no als^lS h? U '"'^ ^V«'"g'°,^ T"7 ^''^^' ^^^^ ^'^"^'^^ movements of a naturarkfnd aJso little birds, sometimes hardly three-(juarter8 of an inch long, in snuff-boxes and watches of enamelled gold Certain artificial figures which have been denominated t^J^JJ •^^'^"^ deserve the name; since trick and confederacy are more or Ccon- cemed m their operation. To this head belong a number of figures anparenily sprakTns by mechanism; a clock which begins to strike, or to play, when a nerson St« n Sign of holding up his finger; this effect being probabV prlduc^ed ^ a c^"^^^^^^ green-finch, or other little bird, instructed to set off the detente of the wheelwork ^ a «gnal. It IS likely, also, that the chess player of Von Kempelen, which excited to much wonder m the last century, had a concealed confederate. Likewise the very ingenious ie ^ Sn\T™L ;f E^sene^^^^ •""Xr^ "'^^' ^"^^^f' ^"^^^^^ hors'emen and rope Z! cers, constructed at i^isenerz, m Styria, are probably no more true automata than thp {^yT^Z'Zitziot"'''''' '"'* "^ """'"«' - ^-' perfect rr ; ;„w"„s'o? The moving power of almost all automata is a wound-up steel sprin.' • because in mm parison w.lh other means of giving motion, it takes up the smaUesTrcJ>m is easiest ^^^^^^ cealed, and set a-go,ng. Weights are seldom employed, and only in a n^rt^ll ITv Th; employment of other moving powers is more iimitedl sometimes fine 3 is mLetoTaH on the circumference of a wheel, by which the rest of the mechanism h moved plrthi ^me purpose water has been employed ; and, when it is made to yXn to an at^cham^^^^^^^ It causes sufficient wind to excite musical sounds in pipes. In particular cases a uiScsil' V* has been used, as, for example, in the Chinese tumblers, whE only a nhvlc^ui paratus to illustrate the doctrine of the centre of gravity ^ physical ap- Figures are frequently constructed for playthings which move by wheels hardlv vi.iWi. An example of this simplest kind of automaton which may be LS^rced here aliUi^ trating the self-acting principles of manufactures, is shown in he Xure ' Fig. 102 exhibits the outlines of an automaton, representing a swan with M,it«M. combm^ovements. The mechanism may be 'described, fo? ^h^sake of cleaJnes's of explanation, under dis- tinct heads. The first relates to the motion of the whole figure. By means of this part it swims upon the water, in directions changed from time to time without exterior agency. Another construc- tion gives to the figure the faculty of bending its neck on several occasions, and to such an extent that it can plunge the bill and a portion of the head under water. Lastly, it is made to move its head and neck slowly from side to side. On the barrel of the spring, wheel thprp ie » r««;« ,„i, i i j . , . ^ exterior to the usual ratchet The wheel 2 movP.Tl n ' ""^'^^ ^' '^^^"'^ ^^'"^^ ^"^^ ^^^ P^"'"" «^ l^e wheel 2. of thriatter Tlfth! ffu ''"^.' ''^^'^'^ "^^'^^^ ^" ^«««J 1'"^^, and on the long axis lotJ by \he ^^^^^^ %'7h'' %Z^^''^ or water.wheel, the paddles of which are open^ in the bouom of ih. fii ""^ '^'^^ rudder-wheels extend through an oblong nf ♦!!» oH 1 i^ ^^ ^'"""^ "^"^^ »n*« t^e water. They turn in the direction of the arrow, and impart a straight-forward movement to the swan The chamW Lir th'p rpJnr iT''"'' ;;'^"^"'» if "'^^^ ^^'^^ ^^'^t, to prevent moisture blinf thrown Tft^-1 fr / ^ "machinery. By the wheel 4, motion is conveyed to the flj pinionl the fly Itself 6, serves to regulate the working of the whole apparatus, and it is provWed nll^nr'^R^' """^ '^''^'' '" '^^ engraving, to bring it to rest, or' set a goTni^ pleasure. Here, as we may imagine, the path pursued is rectdinear, when the rudder wheels are made to work ma square direction. An oblique bar, seen only in «=ec?^m at 6, moveable about its midd e point, carries at each Pnd « wpK rLf ?u . Vu ™"*" AUTOKATON^. Ill is effected without other agency. For this purpose, the wheel 1 takes into the pinion Y, and this carries round the crown-wheel 8, which is fixed, with an eccentric disc 9, upon a common axis. While the crown-wheel moves in the direction of the arrow, it turns the smaller eccentric portion of the elliptic disc towards the lever m, which, pressed upon incessantly by its spring, assumes, by degrees, the position corresponding with the middle line of the figure, and afterwards an oblique position ; then it goes back again, and reaches its first situation ; consequently through the reciprocal turning of the bar A, and the swim-foot, is determined and varied the path which the swan must pursue. This construction is available with all automata, which work by wheels ; and it is ob- vious, that we may, by different forms of the disc 9, modify, at pleasure, the direction and the velocity of the turnings. If the disc is a circle, for instance, then the changes will lake place less suddenly; if the disc has an outward and inward curvature, upon whose edge the end of the lever presses with a roller, the movement will take place in a serpentine line. The neck is the part which requires the most careful workmanship. Its outward case must be flexible, and the neck itself should therefore be made of a tube of spiral wire, covered with leather, or with a feathered bird-skin. The double line in the interior, where we see the triangles «, e, e, denotes a steel spring made fast to the plate 10, which forms thebottom of the neck ; it stands loose, and needs to be merely so strong as to keep the neck straight, or to bend it a little backwards. It should not be equally thick in all points, but it should be weaker where the first graceful bend is to be made ; and, in general, its stiffness ought to correspond to the curvature of the neck of this bird. The triangles e are made fast at their base to the front surface of the spring ; in the points of each there is a slit, in the middle of which a moveable roller is set, formed of a smoothly turned steel rod. A thin catgut string/, runs from the upper end of the spring, where it is fixed over all these rollers, and passes through an aperture pierced in the middle of 10, into the inside of the rump. If the catgut be drawn straight back towards /, the spring, and consequently the neck, must obviously be bent, and so much the more, the more tightly / is pulled, and is shortened in the hollow of the neck. Hpw this is accomplished by the wheel-work will presently be shown. The wheel 11 receives its motion from the pinion s, connected with the main- wheel 1. Upon 11 there is, moreover, the disc 12, to whose circumference a slender chain is fastened. When the wheel 11 turns in the direction of the arrow, the chain will be so much pulled onwards through the corresponding advance at the point at 12, till this point has come to the place opposite to its present situation, and, consequently, 11 must have performed half a revolution. The other end of the chain is hung in the groove of a very moveable roller 14 ; and this will be turned immediately by the unwinding of the chain upon its axis. There turns, in connexion with it, however, the large roller 13, to which the catgut / is fastened ; and as this is pulled in the direction of the arrow, the neck will be bent until the wheel 1 1 has made a half revolution. Then the drag ceases again to act upon the chain and the catgut ; the spring in the neck comes into play : it becomes straight, erects the neck of the animal, and turns the rollers 13 and 14, back into their first position. The roller. 13 is of considerable size, in order that through the slight motion of the roller 14, a sufficient length of the catgut may be wound off, and the requisite short- ening of the neck may be effected ; which results from the proportion of the diameters of the rollers 11, 13, and 14. This part of the mechanism is attached as near to the side of the hollow body as possible, to make room for the interior parts, but particularly for the paddle-wheels. Since the catgut,/, must pass downwards on the middle from 10, it is necessary to incline it sideways and outwards towards 13, by means of some small rollers. The head, constituting one piece with the neck, will be depressed by the complete flexure of this ; and the bill, being turned downwards in front of the breast, will touch the surface of the water. The head will not be motionless ; but it is joined on both sides by a very moveable hinge, with the light ring, which forms the upper part of the clothing of the neck. A weak spring, g, also fastened to the end of the neck, tends to turn the head backwards ; but in the present position it cannot do so, because a chain at g, whose other end is attached to the plate 10, keeps it on the stretch. On the bending of the neck, this chain becomes slack ; the spring g comes into operation, and throws the head so far back, that, in its natural position, it will reach the water. Finally, to render the turning of the head and the neck practicable, the latter is not closely connected with the rump, while the plate 10 can turn in a cylindrical manner upon its axis, but cannot become loose outwardly. Moreover, there is upon the axis of the wheel 1, and behind it (shown merely as a circle in the engraving) a bevel wheel, which works into a second similar wheel, 15, so as to turn it in a horizontal direction. The pin 16> of the last wheel, works upon a two-armed lever 19, moveable round the point hf ar.d this lever moves the neck by means of the pin 17. The shorter arm of the I I 112 AUTOMATON'. '^'^^ell^^^^^^ «ta„as. As soon as this ,n eon. es the oval ring ouTw^ dfon'i s :r^:n:l-" LmU point h, into the oblique directirshown bv f h/;!^/^^^ 1"/°' ^^^ ^^^^r upon the on ns way right opposite toTs or ll^^^^^^^^^^^ ^hepin 16, having come opposite side; and atlast, when iTh^^sTade an ^^^^^^^^^^ to the The longer arm of the lever follows, of cour4 these nU J. !• ' '* '' ^"'^^ straight. t turns the neek upon its plate 10, by niean; of the ' '" i r"""^'?^ movements, so that this comes into the dotted position^ Tmw be £^ \' 5°?' *« 18 denotes the bill. 105 io d^We'^heToL^tur^^^ ^^«!P^/n it. The man appen. four wheels of the carriage Sv^notrex^^^^^ ^^^°^ ,^"- ^- front.'V some parts are represented ^von Tlar^^ Z^e T^T}.^ fT-^^^^^ ^^ Jig- 105, through the two carrier wheels ipon the wheerm-irl.^ I /t^ K'"" ^^' ^O^, operates of these two wheels, the feet are "e in mot L T. 1 A^'r^* .^^' ""^^"^ °^ the axis hinder foot, move themselves backwards St. lie l^u ^f ,,^«^«-^««^ «. then the right in Iheir hoofs, whUe the Iwo oSTe^ irrw nn^ •''Vk^ ^'^""^ ^"''^ '"^^^^ tacks takes place. The carriage, ho4vi°wirwhTeh ^t . '''^^ ^"^ '''' "^^^^^^ °^ ^^^ ^^^^ its wheels. By studying the mechanism of he JooJ a anVt^r^^^^^^^ ^^'T^ -"P^" we can readilv understand the nrinpinl^« «f ♦/ ' ' the parts connected with it, crank-shaped on both sides where7f^J?« ? ^ movement. The axis of wheel 4 is each foot,'it isbentin an i^po te^^^^^^^^^^^^ but for This crank, or properiv its parf ^"the^t from ih. i'-'^^'^^"^ '? the front view;?g.l04. the swan, and moves like it in an oval sDor« l.^n'>' oT'' '"^tead of the pin J6, in motion through tooth-work but not n\ nTh. ^'•^^•1^'^' » two-armed lever, which gives work renders the motirsmoo^^r V^^^^^^^^^^^ ^^^^^^ pin. This wheel! which it turns alternatelv, to the ^ne and Ihe other s id. > ' ^"/"""J ^1 "'•^^- ^^^'^^"t wheel 4. The toothed arrh or ii!! LI? the other side, by virtue of the rotation of the lever, in a simillitct^u^n th^upt^^^^^^^^^^^ ^^'^ "^ a shorter backward upon the p vot 7" In virtue of th. »-^^' ^"^'^^ i' "'^^^^ ^"^^rd and the foot a will move itseirhrs ob^^luelv btw°'r' -. '^' J''"^'^^°^ °^ '^^ ^rrow. will thereby bend itself fo ward ^IZtJh^^Zl^'T'f'''''^ ^^"^^?' ^"^ the boa, both the other feet are rai ed and bent The fnVnt^". t\ makes the same motion, of hinges, which are so constructed tlmi tl^ey carvfelf nn fnn'.' ""'.t '"? ' '^^ ''°™«' every oblique position of the foot Wifh n,o L^ • I" ^"""^^^^ ^han is necessary at lever turns itseVabout J, in an inVer^ed dir^^^^^^^^^^ !^^ wheel 4, the foot-joint forward, so tha it form^I^Lcute an^le w^^^.' w -"^^^^ ^^ "PPcnnost now twice bent upon its joints. Th?s takes nlfce bv th. ; ^^ '\^'T' ^^^ ^«ot is is led over rollers (as the drawing sLws) to' he fo^'^^^^^^^^ *''.''!!? '' 7^'^^ upper end has its fixed point in the interior of ihM^ is th fastened. As its the eccentric pin r stand'in,^ in the vi n ty of '^'L^^U '^^' hinges. If there was space for it, a rollL would'a'nsl^^ b'eUer than fU' bJ AVENTURINK 118 the recedure of the uppermost joint into the first position, the tension of the chain t ceases again of itselC while the pin r removes from it, and the foot is again extended in a straight line by the small springs operating upon its two under parts, which were previously bent stitfly by the chain. By the aid of the figures with this explanation, it will be apparent that all the fore feet have a similar construction, that the proper succession of motions will be effected through toothed arcs, and the position of the cranks on the axis of the wheels 4 and 6, and hence the advance of the figure most follow. The wheel 6 puts the fly 7 in motion, by means of the small wheel marked 1; on the fixed points of the 4 chains, by means of a ratchet-wheel and a catch, the ne- cessary tension will again be produced when the chains have been drawn out a little. There is sufficient room for a mechanism which could give motion to the head and ears, were it thought necessary. The proper cause of the motions may now be explained. In Jig. 105, a, is a wheel connected with the wound-up spring, by which the motion of the two human figures, and also, if desired, that of the horse may be effected. The axis of the wheel b carries a disc with pins, which operate upon the two-armed lever with its fulcrum c, and thn« causes the bending of the upper part of one of the figures, which has a hinge tXf. On the axis of that wheel there is a second disc c, for giving motion to the other figure ; which, for the sake of clearness, is shown separate, although it should sit alongside of its fellow. On the upper end of the double-armed lever d, there is a cord whose other end is connected with the moving arm, in the situation i, and raises it whenever a pin in the disc presses the under part of the lever. A spring h brings the arm back into the original position, when a pin has passed from the lever, and has left it behind. The pins at c and d may be set at different distances from the middle of the disc, wheieby the motions of the figures by every contact of another pin, are varied, and are therefore not so uniform, and consequently more natural. For the connection of both mechanisms, namely, the carriage with the horse, vari- ous arrangements may be adopted. Two separate traction springs should be employ- ed ; one at a, Jig. 105, in the coach-seat ; the other in the body of the horse. In th« coach-seat at 6, the fly with its pinion, as well as a ratchet-wheel, is necessary. By means of the shaft, the horse is placed in connection with the wagon. It may, however, receive its motion from the spring in the carriage, in which case one spring will be suf- ficient. Upon the latter plan the following construction may be adopted : — ^To the axis of h,Jig. 105, a bevel wheel is to be attached, and from this the motion is to be transmitted to the bottom of the carriage with the help of a second bevel wheel «^ connected with a third bevel wheel t. This again turns the wheel it, whose long axis V goes to the middle of the horse's body, in an oblique direction, through the hol- low shaft This axis carries an endless screw 9, Jig. 103, with very oblique threads, which works into the little wheel 8, corresponding to the wheel 1, through an open- ing in the side of the horse, and in this way sets the mechanism of the horse a-going. With this construction of Jig. 105, a spring of considerable strength is necessary, or if the height of the carriage-seat does not afford sufficient room, its breadth will an- swer for placing two weaker springs alongside of each other upon a common barrel AVENTUllINK According to Wohler's examination, aventurine glass owes its golden iridescence to a crystalline separation of metallic copper from the mass col- ored brown by the peroxide of iron. In the aventurine glaze for porcelain a crystalline separation of green oxide of chromium from the brown ferruginous mass of the glaze produces a similar effect This glaze is j^repared as follows : 31 parts of fine lixiviated dry porcelain earth from Halle, 43 do. do. dry quartz sand, 14 do. do. gypsum, 12 do. do. fragments of porcelain, are stirred up with 300 parts of water, and by repeated straining through a linen sieve uniformly suspended in it, and intimately mixed. To this paste is added, under con- stant agitation and one after the other, aqueous solutions of 19 parts bichromate of potash, 100 " protosulphate of iron, 47 " acetate of lead, and then so much solution of ammonia that the iron is completely separated. The salts of potash and ammonia are removed by frequent decantation with spring water. The baked porcelain vessels are dipped into the pasty mixture obtained as above described in the same manner as with other glazes, and then fired in the porcelain furnace. After this they appear covered with a brown glaze, which in reflected light appears to be filled with a countless number of light gold spangles. Vol. L 114 BALANCE A thm fragment of the glass appears, under the microscope, by transmitted light, as a clear brownish glass, in which numerous transparent green six-sided prisms ol oxide of chromium, and some brownish crystals, probably of oxide of chromium and perox- ide of iron, are suspended. The oxide of chromium therefore separates, on the slow ©ooling of the glaze in the porcelain furnace, from the substance of the glaze — a sili- cate of potash, lime, and alumina — saturated with the peroxide of iron, and shinea through the brownish mass with a golden color. When the aventurine glaze is mixed with an equal amount of colorless porcelain glaze, the glassy mass no lono-er has a brown color after the burning, but a light greenish-grav, and the eliminated erystalline spangles likewise exhibit in reflected light their natural green color. AXE. A tool much used by carpenters for cleaving, and roughly fashioning, blocks of wood. It is a flat iron wedge, with an oblong steel edge, parallel to which, in the ■hort base, is a hole for receiving and holding fast the end of a strong wooden handle. In the coi.per's adze, the oblong edge is at right angles to the handle, and is slightly ourved up, or inflected towards it. AXLES, of carriages — See Wheel Carriages. AXUNGE Hog's lard ; see Fat and Oils. AZOBENZOLDE, and AZOBENZOYLE, products of the action of pure water of ammonia upon oil of bitter almonds, by making the ammonia pass down through a ^ A vrvTM^^ ^^^"^^ with the almond pap. The operation must be continued for weeks. AZOTIZED, said of certain vegetable substances, which, as containing azote, were Bopposed at one time to partake, in some measure, of the animal nature ; most animal bodies being characterized by the presence of much azote in their composition. The veg- A Int^i^^T^^-^"*^'^'^' ^^^^^°^' ^*"^^°' and many others, contain abundance of azote. AZUKE, the tine blue pigment, commonly called smalt, is a glass, colored with ox- ide of cobalt, and ground to an impalpable powder. The manufacture of azure, or smalt, has been lately improved in Sweden, by the adoption of tlie following process : — The cobalt ore is first roasted till the greater part of the arsenic is driven oflF. The residuary impure black oxide is mixed with as much sulphuric acid (concentrated) as wiU make it into a paste, which is exposed at first to a moderate heat, then to a cherry-red ignition for an hour. The sulphate thus obtained is reduced to powder, and dissolved in water. To the solution, carbonate of potash is gradually added, in order to separate the remaining portion of oxide of iron; the quantity of which'de- pends upon the previous degree of calcination. If it be not enough oxidized, the iron IS ditticidt to be got rid of When, from the color of the precipitate, we find that the potash separates merely carbonate of cobalt^ it is allowed to settle, the supernatant liquor is decanted, and precipitated, by means of a solution of silicate of potash, prepared as follows : — Ten parts of potash are carefully mixed with fifteen parts of finely ground flints or sand, and one part of pounded charcoal. This mixture is melted in a crucible of brick day, an operation which requires steady ignition during 6 or 6 hours. The mass, when melted and pulverized, may be easily dissolved in boiling water, adding to it, by little at a time, the glass previously ground. The filtered solution is colorless, and keeps well in the air, if it contains one part of glass for 5 or 6 of water. The silicate of cobalt which precipitates upon mixing the two solutions, is the preparation of co- balt most smtabl© for painting upon porcelain, and for the manufacture of blue glass. Bee Cobalt. B. BABLAH. The rind or shell which surrounds the fruit of the mimosa cineraria ; it eomes from the East Indies, as also from Senegal, under the name of Neb-neb. It eontams gallic acid, tannin, a red coloring matter, and an azotized substance ; but tlie proportion of tannin is smaller than in sumach, galls, and knoppern (gall-nuts of the eouunon oak) in reference to that of gallic acid, which is considerable in the bab- lah. It has been used, in dying cotton, for producing various shades of drab; as a Bubetitute for the more expensive astringent dye-stuffs. BAGASSE The sugar-cane, in its dry, crushed state, as delivered from the sugar- m.»L It is much employed for fuel in the colonial sugar-houses. BAKING. {Quire, Fr. Backen, Germ.) The exposure of any body to such a heat as will dry and consolidate its parts without wasting them. Thus wood, pottery, and porcelain, are baked, as well as bread. BALANCE — ^To conduct arts, manufacturers, and mines, with judgment and success, recourse must be had, at almost every step, to a balance. Experience proves that all material bodies, existing upon the surface of the earth, are constantly solicited by a force which tends to bring them to its centre, and that they actually fall towards it BALANCE. 115 when they are free to move. This force is called gravity. Though the bodies be not free, tha effort of gravity is still sensible, and the resultant of all the actions which it exercises upon their material points constitutes what is popularly called their weight. These weights are, therefore, forces which may be compared together, and bv means of machines may be made to correspond or be counterpoised. To discover whether two weiffhts be equal, we must oppose them to each other in a machine where they act in a similar manner, and then see if they maintain an equi- librium ; for example, we fulfil this condition if we suspend them at the two extremities of a lever, supported at its centre, and whose arms are equal. Such is the general idea of a balance. The beam of a good balance ought to be a bar of well-tempered steel, of Buch form as to secure perfect inflexibility under any load which may be fitly applied to its extremities. Its arms should be quite equal in weight and length upon each side of its point of suspension ; and this point should be placed in a vertical line over the centre of gravity ; and the less distant it is from it, the more delicate will be the balance. Were it placed exactly in that centre, the beam would not spontaneously recover the horizontal position when it was once removed from it. To render its indications more readily commensurable, a slender rod or needle is fixed to it, at ri^ht angles, in the line passing through its centres of gravity and suspension. The point, or rather edge of suspension, is made of perfectly hard steel, and turns upon a bed of the same. For common uses the arms of a balance can be made sufficiently equal to give satisfactory results ; but, for the more refined purposes of science, that equality should never be presumed nor trusted to ; and, fortunately, exact weighing is quite independent of that equality. To weigh a body is to determine how many limes the weight of that body contains another species of known weijiht, as of grains or pounds, for example. In order to find it out, let us place the substance, suppose a piece of gold, in the left hand scale of the balance ; counterpoise it with sand or shot in the other, till the index needle be truly vertical, or stand in the middle of the scale, proving the beam to be horizontal. Now remove gently the piece of gold, and substitute in its place standard multiple weights of any graduation, English or French, till the needle again resumes tho vertical position, or till its oscillations upon either side of the zero point are equaL These weights will represent precisely the weight of the gold, since they are placed in the same circumstances precisely with it, and make the same equilibrium with the weight laid in the other scale. This method of v.eighing is obviously independent of the unequal length as well as the unequal weight of the arms of the beam. For its perfection two requisites only are indispensable. The first is that the points of suspension should be rigorously the same m the two operations; for the power of a given weight to turn the beam being unequal, according as we place it at diflTcrent distances from the centre of suspension, did that point var>' in the two consecutive weighings, we would require to employ, in the second, a different weight from that of the piece of gold, in order to form an equilibrium with the sand or shot originally put in the opposite scale ; and as there is nothing to indicate such inequality m the states of the beam, great errors would result from it. The best mode ot securing agamst such inequality is to suspend the cords of the scales from sharp ed^ed rings, upon knife edges, at the ends of the beam, both made of steel sc hard tempered as to be incapable of indentation. Tlie second condition is, that the balance should be very sensible, that is, when in equilibrium and loaded, it may be disturbed, and its needle may oscillate, by the smallest weight put into either of the scales. This sensibility depe^is solel;jr upon the centre or nail of suspension ; and it will be the more perfect the less friction there is between that knife-edge surface and the plane which supports it Both should therefore be as hard and highly polished as possible; and should not be suftered to press against each other, except at the time of weiiijiing. Every delicate balance of moderate size, moreover, should be suspended within a glass case, to protect it from the agitations of the air, and the corroding influence of the weather. In some balances a ball is placed upon the index or needle (whether that index stand above or below the beam), which may be made to approach or recede from the beam by a fine-threaded screw, with the effect of varying the centre of gravity relatively to the point of suspension, and thereby increasing, at will, either the sensibility, or the stubility of the balance. The greater the length of the arms, the less distant the centre of gravity is beneath the centre of suspensiim, the better polished its central knife-edge of 30°, the lighter the whole balance, and the less it is loaded, the greater will be its sensibility. In all cases the arms must be quite in- flexible. A balance made by Ramsden tor the Royal Society is capable of weighing ten pounds, and turns with one hundredth of a grain, which is the seven-millionth part of the weight. In pointing out this balance to me one evening. Dr. Wollaston told me It was so delicate, that Mr. Pond, then astronomer royal, when making some observations with it, found its indications affected by his relative position before it although It was mclosed in a glass case. When he stood opposite the right arm, that 116 BALANCE FOR WEIGHING COrN". end of the beam preponderated, in consequence of its becoming expanded by the radi- ation of heat from his body ; and when he stood opposite the left arm, he made this preponderate in its turn. It is probable that Mr. Pond had previously adjusted the centres of gravity and suspension so near to each other as to give the balance its maxi- mum sensibility, consistent with stability. Were these centres made to coincide, the beam, when the weights are equal, would rest in any position, and the addition of the smallest weight would overset the balance, and place the beam in a vertical position, from which it would have no tendency to return. The sensibility in this case would be the greatest possible ; but the other two requisites of level and stability would be entirely lost. The case would be even worse if the centre of gravity were higher than the centre of suspension, as the balance When deranged, if free, would make a revolution of no less than a semi-circle. A balance may be made by a fraudulent dealer to weigh falsely though ita arms be equal, provided the suspension be as low as the centre of gravity, for he has only to toss his tea, for instance, forcibly into one scale to cause 15 ounces of it, or thereby, to counterpoise a pound weight in the other. Inspectors of weights, I BALANCE FOR WEIGHING COIN. 117 1 Bhort time ago, before the issue of the new coinage, the same person could weigh only 3,000, as it took a longer time for the scales to indicate. " The bullion scales cannot indicate nearer than 4-lOOths of a grain, at the above rate. " The machine is perfectly free from the sources of error to which the scales are subject, and weighs as quickly, whether the sovereigns are new and of full weighty or old and doubtful ; it can weigh 10,000 in six horns, and divide coin varying only one-fiftieth of a grain." The paper is illustrated by two drawings of the internal arrangement of the machine, *nd a model, showing the action of the tongues and platform. Mr. Oldham exhibited, at the Institute of Civil Engineers, the automaton balance at work, weighing coin, and after describing, with the aid of a diagram and model, the action of some of the more delicate parts of the machine, he observed, that in seeking to obtain extraordinary performances by machinei-v .mechanical propriety of construc- tion was too often overlooked, and premature deterioration, in the action of many parts, was the result The automaton balance was peculiarly worthy of notice, from the judgment exercised in its relative proportions, as was provea by the fact that after being at work for several months, it had become more delicate in detecting slight variations between standard and light coin, than when it was first constructed. Mr. Cotton's object in this invention should be well understood. Public convenience demanded great accuracy in weighing the currency : by the ordinary mode of weighing gold with the bullion scales, although it was due to the banktellers to state that they gave the utmost attention to their mono- tonous duty, it was nearly impossible to guard against the various difficulties detailed in the paper. The injury sustained by the optic nerve, from constantly watching the indicator of the scales, was a serious inconvenience to the operative, which, coupled with the incidental sources of error referred to, created even greater absence of deli- cacy than the papers stated. Errors to the amount of one-third, or even half a grain, were not unfrequent By the " automaton balance," the number weighed in a given time was increased, and undeviating accuracy obtained- The delicacy of the instrument was such, that from thirty to thirty-five coins per minute could be passed through the machine, de- tecting a difference of only one-fifth of a grain. It should be mentioned, that ^uch greater delicacy could be accomplished ; that is, to the one hundredth of a grain, out not at the same rate ; because it would be under- stood that a slow action of the beam was necessary for very small variations, and that must regulate the speed of working; but such delicacy was beyond all useful purposes in those transactions which it was intended to improve. Mr. Cotton said that his attention had been attracted to the point by the incon- veniences to which the " tellers" were subjected in weighing gold for the public; with balances so delicately constructed as the bullion-scales, the agitation of the air, by the sudden opening of a door, or even by the breathing of those around, sufficed to cause eriors. It was possible, also, by pressing the fulcrum against the bridle, to produce such a degree of friction as materially to interfere with accuracy ; and the tellers con- fessed that after weighing two or three thousand coins, the sight was injured, and they no longer observed with the same degree of correctness. He therefore imagined that a machine might be contrived, which, being defended from external influence, might weigh coins as fast as by hand, and within one-fourth of a grain ; but he certainly did not contemplate attaining such perfection as the machine now possessed. His first idea was, that the light coins should be taken off by forceps, and that those of average weight should be pushed off by the succeeding ones ; but it was found that the slightest inaccuracy in the milled edges sufficed to give them a wrong direction ; therefore when he had made the first rough sketch, and consulted with his friend, the late Mr. Ewart, he recommended that Mr. Napier, of York Road, Lambeth, should be employed to make the machine, and to him was due the suggestion of the two alternately advancing tongues, as well as several other arrangements of the machinery, which he had so successfully constructed. ^ When the first machine was tried, out of 1000 sovereigns IfiO were found to be light They were given to a teller to be verified, and he returned several of them aa being of the proper weight ; but, on again weighing them more carefully, the results given by the machine were found to be correct. As an instance of how many circum- Blances should betaken into consideration in delicate machines, he might mention, that after being used for a time, the machine varied in its results, and, on examination, it was discovered, that the end of the lever which traversed the pendant had become magnetic, and thus affected the balance. An ivory end was substituted, and ever since tliat period its accuracy had been maintained- Mr. W. Miller observed that the efficiency of any scales must be determined, in a great degree, by the fineness of the edge of the fulcrum of the beam ; and it would be 118 BALSAMS. 11 easily imagined that the friction, to which the edee in a pair of bullion scales was subjected, whilst weighing 5000 or 6000 sovereigns per day, must soon impair its delicacy, and consequently the efficiency of the whole apparatus ; for, whether the sovereigns were light or heavy, the beam must turn upon its fulcrum. Such was not the case with Mr. Cotton's machine ; its beam did not act at all, unlesa a light sov- ereign was placed upon the platform ; so that, among 1000 sovereigns, if only 100 were light, the beam of the machine would onljr move 100 times, while that of the ordinary scales would oscillate 1000 times. An immense advantage was thus given to the machine in point of durability. All weighing was but an approach to correctness, and the nearest point to which the best kind of common scales were sensible, might be stated as y^ jths of a grain, and 4th of a grain would hardly cover their errors; but the machine was sensible to j-jgths of a grain, and^^ths would fully cover its errors, which were not a twentietn part so numerous as tliose of the scales. BALSAMS (Baumesj Ft. Balsame, Germ.) are native compounds of ethereal or essential oils, with resin, and fretjuently benzoic acid. Most of them have the con- sistence of honey ; but a few are solid, or become so by keepin?. They flow either spontaneously, or by incisions made from trees and shrubs in tropical climates. They possess peculiar powerful smells, aromatic hot tastes, but lose their odoriferous pro- perties by long exposure to the air. They are insoluble in water; soluble, to a con- siderable degree, in ether; and completely in alcohol. When distilled with water, ethereal oil comes over, and resin remains in the retort. 1. BAI.SAMS WITH BENZOIC ACID : Balsam of Peru is extracted from the myroxylon peruiferumy a tree which grows in Peru, Mexico, &c. ; sometimes by incision, and sometimes by evaporating the decoction of the bark and branches of the tree. The former kind is very rare, and is imported in the husk of the cocoa-nut, whence it is called balsam eii coque. It is brown, trans- parent only in thin layers, of the consistence of thick turpentine ; an agreeable smell, an acrid and bitter taste ; formed of two matters, the one liquid, the other cranular, and somewhat crjstalline. In 100 parts, it contains 12 of benzoic acid, 88 of resin, with traces of a volatile oil. The second sort, the black balsam of Peru, is much more common than the pie- ceding, translucent, of the consistence of well-boiled simp, very deep red-brown color, an almost intolerably acrid and bitter taste, and a stronger smell than the other balsam. Stoltze regards it as formed of 69 parts of a peculiar oil, 20'7 of a resin, little soluble in alcohol, of 6*4 of benzoic acid, of 0-6 of extractive matter, and 09 of water. . From its high price, balsam of Peru is often adulterated with copaiba, ofl of tur- pentine, and olive oil. One thousand parts of good balsam should, by its benzoic acid, saturate 75 parts of crystallized carbonate of soda. It is employed as a perfume for pomatums, tinctures, lozenges, sealing-wax, and for chocolate and liqueurs, instead of vanilla, when this happens to be very dear Liquid ambeTy Storax or StyraXy flows from the leaves and trunk of the liquid amber shjracijlua, a tree which grows in Virginia, Louisiana, and Mexico. It is brownish ash-gray, of the consistence of turpentine, dries up readily, smells agreeably, like ben- zoin, has a bitterish, sharp, burning taste ; is soluble in 4 parts of alcohol, and contains only 1-4 per cent, of benzoic acid. Balsam of Tolu flows from the trunk of the myroxylon tolui/trum, a tree which grows in South America ; it is, when fresh, of the consistence of turpentine, is brownish-red, dries into a yellowish or reddish brittle resinous mass, of a smell like benzoin ; is soluble in alcohol and ether ; aflbrds, with water, benzoic acid. Chinese varnish flows from the bark of the jSugia sinensis ; it is a greenish yellow turpentine-like substance, smells aromatic, tastes strong and rather astringent, in thin layers dries soon into a smooth shining lac, and consists of resin, ethereous oil, and ben- zoic acid. It is soluble in alcohol and ether ; and has been employed, immemorially, in China, for lackering and varnishing surfaces, either alone or colored. Balsams without benzoic acid : — Copaiva balsam, balsam of copahu or capivi, is obtained from incisions made in the trunk of the Copaifera officinalis, a tree which grows in Brazil and Cayenne. It is pale yellow, middling liquid, clear transparent, has a bitter, sharp, hot taste; a penetrating disagreeable smell ; a specific gravity of from 0-950 to 0*996. It dissolves in absolute alcohol, partially in spirit of wine, forms with alkalis, crystalline compounds. It con- sists of 45*59 ethereous oil, 52*75 of a yellow brittle resin, and 1*66 of a brown viscid resin. The oil contains no oxygen, has a composition like oil of turpentine, dissolves caoutchouc (according to Durand), but becomes oxydized in the air, into a peculiar species of resin. This balsam is used for making paper transparent, for certain lackers, and in medicine. BANDANNA. 119 i \ This substance, which is extensively used in medicine, is often adulterated. For- merly some unctuous oil was mixed with it, but as this is easily discovered by ita insolubility in alcohol, castor oil has since been used. The presence of this cheaper cil may be detected, 1, by agitating the balsam with a solution of caustic soda, and setting the mixture aside to repose ; when the balsam will come to float clear on th« top, and leave a soapy thick magma of the oil below ; 2, when the balsam ia boiled with water, in a thin film, for some hours, it will become a brittle resin on cooling, but it will remain viscid if mixed with castor oil ; 3, if a drop of the oil on white paper be held over a lamp, at a proper distance, its volatile oil will evaporate and leave the brittle resin, without causing any stain around, which the presence of oil will produce; 4, when three drops of the balsam are poured into a watch-glass, alongside of on© drop of sulphuric acid, it becomes yellow at the point of contact, and altogether of a saflfron hue when stirred about with a glass rod, but if sophisticated with castor oil, the mixture soon becomes nearly colorless like white honey, though after some time the acid blackens the whole in either case ; 5, if 3 parts in bulk of the balsam be mixed with 1 of good water of ammonia (of 0'970 sp. grav.) in a glass tube, it will form a transparent solution, if it be pure, but will form a white liniment if it con- tains castor oil ; 6, if the balsam be triturated with a little of the common magnesia alba, it will form a clear solution, from which acids dissolve < jit the magnesia, and leave the oil transparent, if it be pure, but opaque if it be adulterated. When tur- pentine is employed to falsify the balsam, the fraud is detected by the smell on heat- ing the compound. Mecca balsam, or opobalsam, is obtained both by incisions of, and by boiling, the branches and leaves of the Balsamodendron Gileadense, a shrub which grows in Arabia Felix, Lesser Asia, and Egypt. When fresh it is turbid, whitish, becomes, by degrees, transparent ; yellow, thickish, and eventually solid. It smells peculiar, but agreeable ; tastes bitter and spicy ; does not dissolve completely in hot spirit of wine, and contains 10 per cent, of ethereous oil, of the specific gravity 0*876. Japan lac varnish flows from incisions in the trunk of the Rhus Vemix (Melanorrhta usilata) which is cultivated in Japan, and grows wild in North America. The juice becomes black in the air ; when purified, dissolves in very little oil ; and, mixed with coloring matter, it constitutes the celebrated varnish of the Japanese. For Benzoin and Turpentine, see these articles in their alphabetical places. BANDANNA. A style of calico printing, in which white or brightly colored ypots are produced upon a red or dark ground. It seems to have been practised from time immemorial in India, by binding up firmly with thread, those points of the cloth which were to remain white or yellow, while the rest of the surface was freely subjected to the dyeing operations. The European imitations have now far surpassed, in the beauty and precision of the design, the oriental patterns ; having called into action the refined resources of mechanical and chemical science. The general principles of producing bright figures upon dark grounds, are explained in the article Calico-printing ; but the peculiarities of the BandauHa printing may be conveniently introduced here. In Brande's Journal for July, 1823, 1 described the Bandanna gallery of Messrs. Monteith at Glasgow, which, when in full action some years ago, might be reckoned. the most magnificent and profitable printing apartment in the world. The white spots were produced by a so- lution of chlorine, made to percolate down through the Turkey red cotton cloth, is certain points defined and circumscribed by the pressure of hollow lead types in plates^ in a hydraulic press. Fig. 106 is an elevation of one press; A, the top or entablature; B B, the cheeks or pillars ; C, the upper block for fastening the upper lead perforated pattern to ; D, the lower block to which the fellow pattern is affixed, and which moves up and down with the piston of the press ; E, the piston or ram ; F, the sole or base ; G, the water-trough, for the discharged or spotted calico to fall into ; H, the small cistern, for the aqueous chlorine or liquor-meter, with glass tubes for indicating the height of liquor inside of the cistern ; e e, glass stopcocks, for admitting the liquor into that cistern from the general reservoir; //, stopcocks for admitting water to wash out the chlorine ; g g, the pattern lead- plates, with screws for setting the patterns parallel to each other; m m, projecting angular pieces at each corner, perforated with a half- inch hole to receive the four guide-pins rising from the lower plate, which serve to secure accuracy of adjustment between the two faces of the lead pattern plates ; h h, two rollers which seize and pull through the discharged pieces, and deliver them into the water- trough. To the left of D there is a stopcock for filling the trough with water; 2, is the waste lube for chlorine I'quor and water of washing. The contrivance for blowing a Stream of air across the cloth, through the pattern tubes, is not represented in the figure- I! (1 1 1 M nil ■1 ! 120 BANDANNA. Sxteen engines similar to the above, each possessing the power of pressing vnik several hundred tons, are arranged in one line, in subdivisions of four ; the spaces ]0« between each subdivision serving as passages to allow the workmen to go readily flx)m the front to the back of the presses. Each occupies twenty-five feet, so that the total length of the apartment is 100 feet. To each press is attached a pair of patterns in lead, (or plates, as they are called,) the manner of forming which will be described in the sequel. One of these plates is fixed to the upper block of the press. This block is so contrived, that it rests upon a kind of universal joint, which enables this plate to apply more exactly to the under fellow- plate. The latter Bits on the moveable part of the press, conmionly called the sill. When this is forced up, the two patterns close on each other very nicely, by means of the guide-pins at the corners, which are fitted with the utmost care. The power which impels this great hydrostatic range is placed in a separate apart- ment, called the machinery room. This machinery consists of two press cylinders of a peculiar construction, having solid rams accurately fitted to them. To each of these cylinders, three little force-pumps, worked by a steam-engine, are connected. The piston of the large cylinder is eight inches in diameter, and is loaded with a top-weight of five tons. This piston can be made to rise about two feet through a leather stuffing or collar. The other cylinder has a piston of only one inch in diameter, which is also loaded with a top-weight of five tons. It is capable, like the other, of being raised two feet through its collar. Supposing the pistons to be a their lowest point, four of the six small force-pumps are put in action by the steam-engine, two of them to raise the large piston, and two the little one. In a short time, so much water is injected into the cylinders, that the loaded pistons have arrived at their his;hest points. They are now ready for working the hydrostatic discharge-presses, the water pressure being conveyed from the one apartment to the other, under ground, through strong copper tubes, of small ealibre. Two valves are attached to each press, one opening a communication between the lai^ ■«l BANDANNA. 121 T j«, «r tiio nrp<5«? the other between the small driving-cylin- driving^jylinder and t^e cylrnder oi the P'^f ?/^^^^^^^ y^ ^le under-block of the press der and the press. The f^"^^'? ^^^^^ „^ffhe secS to give the requisite compression into contact w.th the upper-block ; that ^^^he ^^"°7 ^^^ purpose of discharging the to the cloth. A thurd valve is attached to the Press, lor i P^ ^^ ^^ water from its cylinder, when the press is to be relaxed, in oraer xo "^FrcSS \wefrto fourteen pieces of cloth, previously dyed T-^ey-^^^^^^^^^ over rchTher, as parallel as possible, ^Y a particular m-^^^^^ These P^^^^^ ^^^^^^^^^ then rolled round a wooden cylinder ^^f .^ij^ *^^^^^^ of the foiiteen lay- now placed in its proper situation at the back oVt^rnwnthrouih between them, by hix>ks f»rs of cloth equal to the area of the plates, is next drawn througn t>«^een i ,3 auachfdt'the two corners of the -bs ^n open ng the vv eonne^^ .^^^^^^ inph drivin<'-cylinder, the water enters the cylmder of the press, ana ins'^""> , . The Xuve force here will, therefore, be 5 tons X 8.=320 tous , the ^^ of c^^nd^e« ie"ng to each other, as the sqaares of their respecUve d'^'°»'«,'^-The cloth .s thus con densrf between the leaden pattern-plates with a pressure of 320 tons, in a couple ci "Tt^'e7t\S;!t?o\Zi??h"/bCrng ^-discha^in. li,u„r (a,„eo«s chlorine oh. on the pipes and cisterns containing this liquor are all ^^^^^^^ ^Jf^^^,, ^_ :_ theuoDer From the measure-cUtem H, the liquor is allowed to flow into the hollows mine upper lea^Xe wS^n^e'nScends on the cloth, and percolates through it, extracting m its pas- sa^eTh^T^key^^^^^^ The liriuor is finally conveyed into the waste pipe, from a groove infheundeT block As soon as the chlorine liquor has passed through, water is admit- ^d in a similar manner, to wash away the chlorine ; othenvise, upon ^^^^^^^^^^^ sure the outline of the figure discharged would become ragged. . The passage ol inecus- rar'4 liquor as well as of the water^hrough the cloth, is occasionally aided by a Pneu- mat'c apparatus, or blowing machine; consisting of a large gasometer, from which wr ^uS to a moderate pressure may be allowed to f-'^^^^^^^l^^^^^^^^ 1^^! liquid upon the folds of the cloth. By an occasional twist of the a.r stopcock the worK man also can ensure the equal distribution of the discharging liquor, oy.^' the whole ex- Stvations in the upper plate. When the demand for goods is very brisk, the air appara- tus is much employed, as it enables the workman to double his Product. The time requisite for completing the discharging process in the first press is sum- cient to enable the other three workmen to put the remaining fifteen presses m Play- i he dischar-er proceeds now from press to press, admits the liquor, the air, and the water, and is followed at a proper interval by the assistants, who relax the press, move forwards anothe quire of the clSth, and then restore the pressure. Whenever the sixteenth press has been iquored, &c., it is time to open the first press. In this routme, about ten mm- uSs are employed; thkt is, 224 handkerchiefs (16+14) are discharged every. ten mmut^. The whole cloth is drawn successively forward, to be successively treated in the above ""when the cloth escapes from the press, it is passed between the two rollers in f[ont|from which it falls into a trough of water placed below. It is finally carried off to the wash- ing and bleaching department, where the lustre of both the white and the red is con- siderably brightened. . . . -,- , ^^, loonft By the above arrangement of presses, 1600 pieces, consisting of 12 yards each=19,200 yards, are converted into Bandannas in the space of ten hours, by the labor ol lour "^Th^ patterns, or plates, which are put into the presses to determine the white figures on the cloth, are made of lead in the following way. A trelUs frame of cast iron, one inch thick, with turned-up edges, forming a trough rather larger than the intended lead pattern, is used as the solid ground-work. Into this trough, a lead plate about one nail inch thick, is firmly fixed bv screw nails passing up fVom below. To the e; gesof this lead plate, the borders of the piece of sheet-lead are soldered, which covers the whole outer surface of the iron frame. Thus a strong trough is formed, one inch deep. 1 ne "Pn?M border gives at once great strength to the plate, and serves to confine the liquor. A inm sheet of lead is now laid on the thick lead-plate, in the manner of a veneer on toUet- tables,and is soldered to it round tfie edges. Both sheets must be made very smo^Hh beforehand, by hammering them on a smooth stone table, and then finishing with a plane: the surface of the thin sheet (now attached) is to be covered with drawing paper, pasleU i 122 BARYTA. II on, and npon this the pattern is drawn. It is now ready for the ctitter. The first thing which he-does is to fix down with brass pins all the parts of the pattern which are to be left solid. Ue now proceeds with the little tools generally used by block- cutters, which are fitted to the different curvatures of the pattern, and he cuts per- pendicularly quite through the thin sheet The pieces thus detached are easily lifted out; and thus the channels are formed which design the white figures on the red cloth. At the bottom of the channels, a sufficient number of small perforations are made through the thicker sheet of lead, so that the discharging liquor may have free ingress and egress. Thus, one plate is finished, from which an impression is to be taken by means of printers' ink, on the paper pasted upon another plate. The impression is taken in the hydrostatic press. Each pair of plates constitutes a set, which may be put into the presses, and removed at pleasure. BARBERRY. The root of this plant contains a yellow coloring matter, which is soluble in water and alcohol, and is rendered brown by alkalis, the solution is em- ployed in the manufacture of Morocco leather. BARILLA A crude soda, procured by the incineration of the salsola soda, a plant cultivated for this purpose in Spain, Sicily, Sardinia, . " ""u' 'J*' ""^ J'«te«an potaUon, so called intoxication caused by Irer '^nd Th^'ni™ r"" ""^ •""■^""- ^"^'""^ ^P^»''^ "t ">« iarfey. We may, indeed Infer frl!^?'-"* 7^? J"?"y denominated it the wine of go„s*t„ our beerVe"etC am™" ie\„"cTnr^^^^^^^ historians, that drinks anall people of our temperate zone ; and'they are st^fJhi '-^ f-K"** '" ^'""■- "''°'''' "^"^ Where the vine is not an object of rnstlcTusSd^' ""'""^ ""^^'^^ '" '^"^ "^ fJeLZsT-"'"" "'■ '^"' " ""^ "' <"■ •'^^'""S. ""y fe conveniently considered under Jley'^a"nd'^"'s"""°" "'""" """^ productions wtich enter Into its composiUon; or of of mamnVand"'masWn? '^"'' "'"^' ''"''"'° '» «' " f- -"^-g •-- ; or the processe, J S: i?rrrtifn V^SK"^; r ""= ■-"^ "«>' -^ "OP'- ferLmatv^dl'nt^rWwWc^ fittest. There are'urjpSs of barl^^he Ct' *"" /'"' '^' ^■"'"'"« " ^^ f" '"« two seeds arranged in a row „„ Vi. b ' T"!™'" ««'sa« or common barify, having seeds sprin, from one potoTso that fsdoubltlwt*"'*^ he.as,ickon, ia whik thref is the proper barley, and is much th. i,r» ^ a '"'^.W^ently six seeds. The former England, but is much cu iva^«l ,^%i fF /'"? ^™" ' "" '"'" '^ «"'« ^""^-^ in ha5ypli„tadaprert„rcoS count^"'%t"fi^^^^^ i^ar or 4,gg ; being a the denser and arger its seed and ihT .hlo. ■?\'''*,'''™.°''' '» "^^'"^ ^'^^ f^"""^, barley is dislinguishS in these res„eit(Vo,^?h^,'%^"K^ Sutfolk pact grain thaS barky " the w5?ht of a W^^^- ^ Aberdeenshire. Bigg is a less com- the former is only aboL 47 IbT ^ile that of » h >, ."'r'^.'^l^'''''^ '="''''= '"'*'^^^ "^ ^'"Tb/^riirork'ir^^^^^ p™t"iircroth~''' ^' '^■ IM measures of average English barky thereby swell into 124. 100 _ rf Z S'=^<='' ditto, . . j2,, «sSr5S,S;s5-FSs r^. 3. ^.,„ Of course taking up most walT ' ^ "^'''' *" ^""^"^^^ ^^^ P^""'*^'" '^'^*«st 3-52 parts of gluten, 5.2lTs^r 4 62 0^1,1 i of r' 1'^^^^ coagulated albunen, water. The loss aiiounted to f I2 Tn^hl.T' ^'^ ^^^ Phosphate of lime, and 9-37 of volatileoilof a concrete nature whir Jr^^ '^°"^^ ^^ «^^^^ ^ Peculiar mented malt wash Tie Wmsxrvf Tr nl r^^""''^ '^', T^"^ «^ ^^^tilling fe.-. solvent action of alcohd ; and neve;^amlSo Ir^ ZTf ^''"^ ''"^^^^ ^'^'^ ^> ^^« The husk also contains sime ofThYt f:ad"o^' %fZ ho'.ht^h'at'hfhiS T ^'°""."'- barley a peculiar principle, to which he save the name of A^L^W I . ^ discovered m rated from starch by the action of both cold aid^b^^g watf^-^^; Snd'th:' by' ^. «l ing barley meal successively with water, he obtained from 89 to 90 parts of a farinaceous substance, composed of from 32 to 33 of starch, and from 57 to 58 othordeiite. Emhof obtained Irom barley seeds, 70-05 of flour, 18-75 of husks or bran, and 11-20 of water. According to Proust, hordeine is a yellowish powder, not unlike fine saw-dust. It contains no azote, for it aflfords no ammonia by distillation, and is therefore very dissimi- lar 10 "lut^n. In the germination of barley, which constitutes the process of malting, the proportion of hordeine is greatly diminished by its conversion into sugar and starch. Other chemists suppose that the hordeine of Proust is merely a mLXture of the bran cf the barley with starch and gluten. It is obvious that the subject stands in need of new chemical researches. In barley the husk constitutes from one fourth to one^ fifth of the whole weight; in oats it constitutes one third; and in wheat one tenth. From the ana- lysis of barley rfuur recently made, it appears to consist in 1000 parts : of water, 100 ; al- bumen, 22-3 ; sugar, 56 ; gum or mucilage, 50 ; gluten, 37-6 ; starch, 720 ; phosphate of lime, 2-5. . j • 2. The hop, humulus lujmlus, the female flowers of the plant. Ives first directed attention to a yellow pulverulent substance which invests the scales of the calkins, amounting to about one eighth of their weight ; and referred to it the valuable properties which hops im- part to beer. We may obtain this substance by drjins the hops at a temperature of 86° F., introducing them into a coarse canvass bag, and shaking it so that the yellow powder shall pass through the pores of the canvass. This powder bears some resemblance to lyco- podiunf. Of the 13 parts in 100 of this powder, 4 parts are foreign matters, derived from me scales of the cones ; leaving 9 parts of a peculiar granular substance. When distilled with water, this substance affords two per cent, of its weight ( j2_ for 100 times the weight of hops) of a volatile colorless oil, to which the plant owes its peculiar aroma« This oil dissolves in water in considerable quantity. It appears to contain sulphur (for it blackens solutions of silver), and also acetate of ammonia. No less than 65 per cent, of the yellow dust is soluble in alcohol. This solution, treated with water and distilled, leaves a reein, which amounts to 52-5 per cent. It has no bitter taste, and is soluble in alcohol and ether. The watery solution from which the resin was separated contains the bitter substance which has been called lupuline by Payen and Chevallier, mixed with a little tannin and malic acid. To obtain this in a state of purity, the free acid must be saturated with lime, the solution evaporated to dryness, and the residuum must be treated with ether, which removes a little resin ; after which the lupuline is dissolved out by al- cohol, which leaves the malate of lime. On evaporating away the alcohol, the lupuline remains, weighing from 8-3 to 12-5 per cent. It is sometimes white, or slightly yel- lowish, and opaque, sometimes orange yellow and transparent. At ordinary tempera- tures it is inodorous, but when heated strongly it emits the smell of hops. It possesses the characteristic taste and bitterness of the hop. Water dissolves it only in the propor- tion of 5 per cent., but it thereby acquires a pale yellow color. Lupuline is neither acid nor alkaline ; it is a ited upon neither by the dilute acids nor alkalis, nor by the solutions of the metallic salts ; it is quite soluble in alcohol, but hardly in ether. It contains apparently no azote, for it affords no ammonia by destructive distillation ; but only an empyrjumatic oil. The yellow dust of hops contains, moreover, traces of a fatty matter, gum, a small quantity of an azoiized substance, and several saline combinations in minute quantity. Boiling water dissolves from 19 to 31 per cent, of the contents of the dust, of which a large proportion is resin. Ives thought that the scales of the catkins of hops, when freed from the yellow powder, contained no principles analogous to it ; but Payen and Chevallier have proved the contrary. The cones of hop give up to boiling alcohol 36 per cent, of soluble matter; while the same cones, stripped of their yellow powder, yield only 26 per cent. ; and further, these chemists found the same principles in the different parts of the hop, but in diflerent proportions. The packing of the hop catkins or cones is one of the most important operations towards the preservation of this plant ; and is probably the cause of the enormous dif- ference in value between the English and French hops after a few years keeping. The former, at the end of six years, possess still great value, and may be sold as an article only two or three years old ; while the latter have lost the greater part of their value in three years, and are no more saleable at the end of four. In France, it is packed merely by tramping it with the feet in sacks. Under this slight pressure, large interslilial spaces are left amid the mass of the hops, through which the air freely circulates, car- rying oft' the essential oil, and oxygenating some of the other proximate principles, so as to render them inert. By the English method, on the contrar)', the hops, after being well rammed into strong sacks hung in frames, are next subjected to the action of a hydraulic press. The valuable yellow powder thus enclosed on every side by innu- merable compact scales, is completely screened from the contact of the atmosphere, and from all its vicissitudes of humidity. Its essential oil, in particular, the basis of its flavor, is preserved without decay. ij 128 BEER. According to the experiments of Chevallier and Payen upon the hops of England Fenders, the Netherlands, and the department of the Vosges, those of the county of Kent afforded the largest cones, and were most productive in useful secreted and soluble mat- ters. Next lo ihem were the hops of Alost. The best hops have a golden yellow color, large cones, an agreeable aroma : when rub- bod between the hands, they leave yellow traces, powerfully odoriferous, without any broken portions of the plant, such as leaves, stems, and scaly fragments. When alcohol IS digested on good hops, from 9 to 12 per cent, of soluble yellow matter maybe obtained by evaporating it to drjness. Tliis is a good test of their quality. The best-flavored and palest hops are packed in sacks of fine canvass, which are call- ed pockets, and weigh about 1^ cwt. each. These are bought by the ale brewer. The stronger-flavored and darker-colored hops are packed in bags of a very coarse texture like door-mats, called hop bags : these contain generally about 3 cwt., and are sold to the porter and beer brewers. After the end of a year or two, hops are reckoned to have lost much of their marketable value, and are then sold lo the second-rate porter brewers, un- der the nanie of old hops. The finest hops are grown in the neighborhood of Canterbury : but those of Worcester have an agreeable mildness of flavor, greatly admired by many ale drinkers. When the bitter and aromatic principles disappear, the hops are no better Uian so much chaff; therefore, an accurate chemical criterion of their principles would be a great benefit to the brewer. U. Malting.— This process consists of three successive operations: the steeping: the couching, sweating, and flooring; and the kiln-drying. The steeping is performed in large cisterns made of wood or stone, which being filled with clear water up to a certain height, a quantity of barley is shot into ihem, and weU stured about with rakes. The good grain is heavy, and subsides; the lighter giains, which float on the surface, are damaged, and should be skmimcd oflf; for they would in- jure the quahly of the malt, and the flavor of the beer made with it. They seldom amount to more than two per cent. More barley is successively emptied into the steep cistern, till the water stands only a few inches, about five, above its surface ; when this is levelled very carefully, and every light seed is removed. The steep lasts from forty to sixty hours, according to circumstances; new barley requiring a longer period than old, and bigg re- quiring much less time than barley. During this steep, some carbonic acid is evolved from the grains, and combines with the water, which, at the same time, acquires a yellowish tinge, and a strawy smell, from dissolving some of the extractive matter of the barley husks. The grain imbibes about one half its weight of water, and increases in size by about one fifth. By losing this ex- tract, the husk becomes about one seventieth lighter in weight, and paler in color. The duration of the steep depends, in some measure, upon the temperature of the air, and is shorter in summer than in winter. In general from 40 to 48 hours will be found sufficient for sound dry grain. Steeping has for its object to expand the farina ol the barley with humidity, and thus prepare the seed for germination, in the same way as the moisture of the earth prepares for the growth of the radicle and plumula in seed sown m it. Too long continuance in the steep is injurious; because it prevents the germination at the proper time, and thereby exhausts a portion of the vegetative power: It causes also an abstraction of saccharine matter by the water. The maceration is known to be complete when the grain may be easily transfixed with a needle, and is swollen to Its full size. The following is reckoned a good test :— If a barley-corn, when pressed between the thumb and fingers, continues entire in its husk, it is not suflSciently steeped : but If It sheds Its flour upon the fingers, it is ready. When the substance exivles in the lorm of a milky juice, the steep has been too long continued, and the barley is spoiled foi germination. In warm weather it sometimes happens that the water becomes acescent before the gram IS thoroughly swelled. This accident, which is manifest to the taste and smell, must be unmediately obviated by drawing oflf the foul water through the tap at the bottom of the cistern, and replacing it with fresh cold water. It does no harm to renew it two or three times at one steep. The co«cA.— The water being drawn off, and occasionally a fresh quantity passed through, to wash away any slimy matter which may have been generated in warm weather, the barley is now laid upon the couch floor of stone flags, in square heaps from 12 to 16 inches high, and left in that position for 24 hours. At this period, the bulk of the gram being the greatest, it may be gauged by the revenue oflicers if thev think nt Itie moisture now leaves the surface of the barley so completely, that it imparts no dampness to the hand. By degrees, however, it becomes warm ; the temperature nsing JO above the atmosphere, whUe an agreeable fruity smell is evolved. At this time, U the hand be thrust into the heap, it not only feels warm, but it gets bedewed with moistJire. At this sweating stage, the germination begins ; the fibrils of the radicle tirst sprout forth from the tip of every grain, and a white elevation appears, that soon BEER. 129 separates into three or more radicles, which grow rapidly larger. About a day after this appearance, the plumula peeps forth at the same point, proceeding thence beneath the husk lo the other end of the seed, in the form of a green leaflet. The greatest heal of the couch is usually about 96 hours after the harley has beea taken out of the steep. In consequence, the radicles tend to increase in length with very great rapidity, and must be checked by artificial means, which constitute the chief art of the maltster. He now begins to spread the barley thinner on the floor, and turns il over several times in the course of a day, bringing the portions of the interior into the exterior surface. The depth, which was originally 15 or 16 inches* is lowered a little at every turning over, liU it be brought eventually down to three or four inches. Two turnings a day are generally required. At this period of spread- ing or flooring, the temperature in England is about 62°, and in Scotland 5 or 6 degrees lower. About a day after the radicles appear, the rudiments of the stem, or of the plimmla, sprout forth, called by the English mahsters the acrospire. It issues from the same end of the seed as the radicle, but turns round, and proceeds within the husk towards the other end, and would there come forth as a green leaf, were its progress not arrested. The malting, however, is complete before the acrospire becomes a leaf. The barley couch absorbs oxygen and emits carbonic acid, just as animals do in breath- ing, but to a very limited extent; for the grain loses only three per cent, of its weight upon the malt floor, and a part of this loss is due to waste particles. As the acrospire creeps along the surface of the seed, the farina within undergoes a remarkable altera- tion. The gluten and mucilage disappear, in a great measure, the color becomes whiter, and the substance becomes so friable Ihat it crumbles into meal between the fingers! This is the great purpose of mailing, and il is known to be accomplished when the plu- mula or acrospire has approached the end of the seed. Now the further growth must be completely stopped. Fourteen days may be reckoned the usual duration of the germinating stage of the malting operations in England; but in Scotland, where the temperature of the couch is lower, eighteen days, or even twenty-one, are sometimes re- quired. The shorter the period within the above limits, the more advantageous is the process lo the maltster, as he can turn over his capital the sooner, and his malt is also somewhat the belter. Bigg is more rapid in its germination than barley, and requires to be still more carefully watched. In dry weather it is sometimes necessary to water the barley upon the couch. Occasionally the odor disengaged from the couch is oflTensive, resembling that of rotten apples. This is a bad prognostic, indicating either that the barley was of bad quality, or that the workmen, through careless shovelling, have crushed a number of tht grains in turning them over. Hence when the weather causes too quick germination, it IS better to check it by spreading the heap out thinner than by turning it too frequently over. On comparing different samples of barley, we shall find that the best develop the germ or acrospire quicker than the radicles, and thus occasion a greater production of the saccharine principle; this conversion advances along with the acrospire, and keeps pace with it, so that the portion of the seed to which it has not reached is still in its un- altered starchy state. It is never complete for any single barleycorn tiU the acrospirt: has come to the end opposite to that from which it sprung ; hence one part of the corn may be sugary, while the other is still insipid. If the grain were allowed to vegetate beyond this term, the radicles being fully one third of an inch long, the future stem would become visibly green in the exterior; it would shoot forth rapidly, the interior of the grain would become milky, with a complete exhaustion of all its useful constituents, and nothing but the husk would remain. In France, the brewers, who generally malt their barley themselves, seldom leave it en the couch more than 8 or 10 days, which, even taking into account the warmer climate of their country, is certainly too short a period, and hence they make inferior wo^t to the English brewer, from the same quantitv of malt. At the end of the germination, the radicles have become I^ longer than the barley, and are contorted so that ihe corns hook into one another, but the acrospire is jus begmnmg to push through. A moderate temperature of the air is best adapted to malt- W.V.; *^»^''^^'i^^>t cannot be carried on well during the heat of summer or The colds of rm Malt-floors should be placed, in substantial thick-walled buildings, without access of the sun so that a uniform temperature of 59° or 60° may prevail inside. bit^aUonTdT ^"^ '''''^ ^ "^^^ "'''^^' ^^^ ^'''^^''^ ""^ ^^^ ^"'''"'*' ^ **"* «.f?"""?'K^^T'"^^'°" * remarkable change has taken place in the substance of the hll?;.cc f "1"^T"' c°"^'^'t"ent has almost entirely disappeared, and is supposed to hTtirn «"i' '^' T''' V}' ^^^^^^«' ^^^^ * portion of the' starch is c^rrteS AiLZf- ♦ °^"*=^j«|«- The change is similar to what starch undergoes when dissolved in water, and digested in a heat of about 160° F. aknig with a little glutei BBBMM .1 ■-> 1 . 130 BEER. The thick paste becomes gradually liquid, transparent, and sweet tasted, and the solution contains now, sugar and gum, mixed with some unaltered starch. The gluten sufTers a change at the same time, and becomes acescent, so that only u certain quantity of starch can be thus converted by a quantity of gluten. By the artificial growth upon the malt- Boor, all the gluten and albumen present in barley is not decomposed, and only about one half of the starch is converted into sugar; the other half, by a continuance of the germination, would only go to the growth of the roots and stems of the plant; but it re- ceives its nearly complete conversion into sugar without any notable waste of substance in the brewer's operation of mashing. The kiln-drying. — When the malt has become perceptibly dry to the hand upon the floor, it is taken to the kiln, and dried hard with artificial heat, to stop all further growth, and enable it to be kept, without change, for future use, at any time. The malt-kiln, which is particularly described in the next page, is a round oi a square chamber, covered with perforated plates of cast iron, whojic area is heated by a stove or furnace, so that not merely the plates on which the malt is laid are warmed, but the air which passes up through the stratum of malt itself, with the eflect of carrying off very rapidly the moisture from the grains. The layer of malt should be about 3 or 4 inches thick, and evenly spread, and its heat should be steadily kept at from the 90th to the 100th degree of Fahrenheit's scale, till the moisture be mostly exhaled from it. During this time the malt must be turned over at first frequently, and latterly every three or four hours. When it is nearly dry, its temperature should be raised to from 145® to 165° F., and it must be kept at this heat till it has assumed the desired shade of color, which is commonly a brownish-yellow or a yellowish-broWn. The fire is now allowed to die out, and the malt is left on the plates till it has become completely cool ; a result promoted by the stream of cool air, which now rises up through the bars of the grate ; or the thoroughly dry browned malt may, by damping the lire, be taken hot from the plates, and eooled upon the floor of an adjoining apartment. The prepared malt musl be kept in a dry lofl, where it can be occasionally turned over till it is used. The period of kiln-drying should not be hurried. Many persons employ two days in this operation. According to the color and the degree of dryin?, malt is distributed into three sorts ; pale, yellow, and brown. The first is produced when the highest heat to which it has been subjected is from 90° to 100° F. ; the amber yellow, when it has sufl'ered a heat of 122°; and the brown when it has been treated as above described. The black malt used by the porter brewer to color his beer, has sufl'ered a much higher heat, and is partially charred. The temperature of the kiln should, in all cases, be most gradually raised, and most equably maintained. If the heat be too great at the beginning, the husk gets hard dried, and hinders the evaporation of the water from the interior sub- stance; and should the interior be dried by a stronger heat, the husk will probably splil, and the farina become of a horny texture, very reuactor)' in the mash-tun. In general, it is preferable to brown malt, rather by a long-continued moderate heat, than by a more violent heat of shorter duration, which is apt to carbonize a portion of the mucilaginous sugar, and to damage the article. In this way, the sweet is sometimes converted into a bitter principle. During the kiln-drying, the roots and acrospire of the barley become brittle, and fall off; and are separated by a wire sieve whose meshes are too small to allow the malt itself to pass through. A quantity of good barley, which weighs 100 pounds, being ju'^tciously malted, will weigh, after drj'ing and sifting, 80 pounds. Since the raw grain, dried by itself at the same temperature as the malt, would lose 12 per cent, of its weight in water, the malt process dissipates out of these remaining 88 pounds, only 8 pounds, or 8 per cent, of the raw barley. This loss consists of— 1^ per cent, dissolved out in the steep water, 3 — dissipated in the kiln, 3 — by the falling of the fibrils, I — of waste. The bulk of good malt exceeds that of the barley from which it was made, by about 8 <«• 9 per cent. The operation of kiln-drying is not confined to the mere expulsion of the moisture from the germinated seeds; but it serves to convert into sugar a portion of the starch which renjained unchanged, and that in a twofold way; first, by the action of the gluten «pon the fecula at an elevated temperature, as also by the species of roasting which the starch undergoes, and which renders it of a gummy nature. (See Starch.) We shall have a proof of this explanation, if we dry one portion of the malt in a naturally dry atmosphere, and another in a moderately warm kiln; the former will yield less saccharine extract than the latter. Moreover, the kiln-dried malt has a pe- culiar, agreeable, and faintly burned taste, probably from a small portion of empy* •4' I BEER. 131 rcumatic oil formed in the husk, and which not only imparts its flavor to the beer, but also contributes to its preservation. It is therefore obvious, that the skilful preparation of the malt must have the greatest influence both on the quantity and quality of the worts to be made from it. If the germination be pushed too far, a part of the extractible mat- ter is wasted ; if it has not advanced far enough, the malt will be too raw, and too much of its substance will remain as an insoluble starch ; if it is too highly kiln dried, a portion of its sugar will be caramelized, and become bitter; and if the sweating was imperfect or irregular, much of the barley may be rendered lumpy and useless. Good malt is dis- tinguishable by the following characters : — The grain is round and full, breaks freely between the teeth, and has a sweetish taste, an agreeable smell, and is full of a soft flour from end to end. It affords no unpleasant flavor on being chewed ; it is not hard, so that when drawn along an oaker\ table across the fibres, it leaves a while streak, like chalk. It swims upon water, while unmalted barley sinks in it. Since the quality of the malt depends much on that of the barley, the same sort only should be used for one malting. New barley germinates quicker than old, which is more dried up ; a couch of a mixture of the two would be irregular, and difllcult to regulate. Description of the maZ/-fei7n.—Fig». 107,108,109,110, exhibit the construction of a well- contrived malt-kiln. Fig. 107, is the ground plan : ^g. 108,is the vertical section; and rtg«.109,and 110, a horizontal and vertical section in the line of the malt-plates. The same letters denote the same parts in each of the figures. A cast-iron cupola-shaped oven is 108 eupported in the middle, upon a wall of brickwork four feet high ; and beneath it, are the grate and its ash-pit. The smoke passes off throu-h two equi-distant pipes into the chim- ney. I he oven is surrounded with four pillars, on whose top a stone lintel is laid : a is the srate 9 inches below the sole of the oven 6 ; c c c c are the four nine-inch strong pilars of hackwork which bear the lintel m ; d d d d d d are strong nine-inch pillar^ Which support the girder and joists upon which perforated plates repose; e denotes a vaul ed arch on each of the four sides of the oven ; / is the space between the kiln tho r n^ ^-fi ' *"'? ^^l'*^^ ^ workman may enter, to inspect and clean the kiln ; g g, o fi,M '.T. "'^fi^' f^^ ^O'^^ ^•'"' "P"'* ^^'^^ the arches rest; h, the space for the ashes th.! [ •; "' ,u ^^^f"""*' o^ the kiln ; / /, junction-pieces to connect the pipes r r with ab^ni thrL r^ * A °^«"aching them is shown in fig. 109. These smoke-pipes lie Uiev a^ ,.?± r T^^' '^' ^'■^" P^*'^'' ^^'^ ^^ the same distance from the side walls: wey are supported upon iron props, which are made fast to the arches. InfigAOS.u 132 BEER, .11 < '» II ill 5 t shows their section; at $ », yig. 109, they enter the chimney, which is provided with two register or damper plates, to regulate the draught through the pipes. These registers aie represented by t t, Jig. 110, which shows a perpendicular section of the chimney. nit fig. 108,is the lintel which causes the heated air to spread laterally instead cf ascending in one mass in the middle, and prevents any combustible particles from falling upon the iron cupola, n n are the main girders of iron for the iron beams o o, upon which the perforated plates ;; lie; q,fig. 108,is the vapor pipe in the middle of the roof, which aUows the steam of the drjing malt to escape. The kiln may be heated either with coal or wood. The size of this kiln is about 20 feet square ; but it may be made proportionally either smaller or greater. The perforated floor should be large enough to receive the contents «]f one steep or couch. The perforated plate might be conveniently heated by steam pipes, laid zig-zag, or in parallel Liies under it; or a wire-gauze web might be stretched upon such pipes. The wooden joists of a common floor would answer perfectly to support this steam-range, and the heat of the pipes would cause an abundant circulation of air. For drying the pale malt of the ale brewer, this plan is particularly well adapted. The kiln-dried malt is sometimes ground between stones in a common corn mill, like oatmeal ; but it is more generally crushed between iron rollers, at least for the purposes of the London brewers. The crushing mill. — The cylinder malt-mill is constructed as shown in^g*. Ill, 112. I is the sloping- trough, by which the malt is let down from its bin or floor to the hopper A of the mill, whence it is progressively shaken in between the rollers B D. The rollers are of iron, truly cylin- drical, and their ends rest in bearers of hard brass, fitted into the side frames of iron. A screw E goes through the upright, and serves to force the bearer of the one roller towards that of the other, so as to bring them closer together when the crush- ing efiect is to be increased. G is the square end of the axis, by which one of the rollers may be turned either by the hand or by power; the other derives its rotatory motion from a pair of eqiml-toolhed wheels H, which are fitted to the other end of the axes of the rollers, rf is a catch which works into the teeth of a ratchet wheel on the end of one of the rollers (not shown in this view.) The lever c strikes the trough b at the bottom of the hopper, and gives it the shaking motion for discharging the malt between the rollers, from the slide sluice a. e e,fig. Ill, are scraper-plates of sheet iron, the edges of which press by a weight against the surfaces of the rollers, and keep them clean. Instead of the cylinders, some employ a crushing mill of a conical-grooved form like a coflfee-mill, upon a large scale. (See the general plan, infra.) The mashing and boiling. — Mashing is the operation by which the wort is extracted, or eliminated from the malt, and whereb) a saccharo-mucilaginous extract is made from it. The malt should not in general be ground into a fine meal, for in that case it would be apt to form a cohesive paste with hot water, or to set, as it is called, and to be difficult to drain. In crushed malt, the husk remains nearly entire, and thus helps to keep the farinaceous particles open and porous to the action of the water. The bulk of the crushed malt is about one fifth greater than that of the whole, or one bushel of malt gives a bushel and a quarter of crushed malt. This is frequently allowed to lie a few days in a cool place, in order that it may attract moisture from the air, which it does very readily by its hygrometric power. Thus, the farinaceous substance which had been indurated in the kiln, becomes soft, spongy, and fit for the ensuing process of watery extraction. Mashing has not for its object merely to dissolve the sugar and gum already present in the malt, but also to convert into a sweet mucilage the starch which had remained unchanged during the germination. We have already stated that starch, mixed with gluten, and digested for some time with hot water, becomes a species of sugar. This conversion takes place in the mash-tun. The malted barley contains not only a portion of gluten, but diastase more than sufficient to convert the starch contained in it^ b) thii means, into sugar. BEER. 198 i ll The researches of Payen and Persoz show, that the mucilage formed by the reaction of malt upon starch, may either be converted into sugar, or be made into permanent gum, according to the temperature of the water in which the materials are digested. We take of pale barley malt, ground fine, from 6 to 10 parts, and 100 parts of starch; we heat, by means of a water-bath, 400 parts of water in a copper, to about 80° F. ; we then stir in the malt, and increase the heat to 140° F., when we add the starch, and stir well together. We next raise the temperature to ISS**, and endeavor to maintain it constantly at that point, or at least to keep it within the limits of 167° on the one «ide, and ISS** on the other. At the end of 20 or 30 minutes, the original milky and pasty solution becomes thinner, and soon after as fluid nearly as water. This is the moment in which the starch is converted into gum, or into that substance which the French chemists call dextrine^ from its power of polarizing light to the right hand, whereas common gam does it to the left. If this merely mucilaginous solution, which seems to be a mixture of gum with a little liquid starch and sugar, be suitably evaporated, it may serve for various purposes in the arts to which gum is applied, but with this view, it must be quickly raised to the boiling point, to prevent the farther operation of the malt upon it. If we wish, on the contrary, however, to promote the saccharine fermentation, for the formation of beer, we must maintain the temperature at between 158° and 167^ for three or four hours, when the greatest part of the gum will have passed into sugar, and by evaporation of the liquid at the same temperature, a starch sirup maybe obtained like that procured by the action of sulphuric acid upon starch. The substance, which oper- ates in the formation of sugar, or is the peculiar ferment of the sugar fermentation, may be considered as a residuum of the duten or vegetable albumen in the germinating grain : it is reckoned by Payen and Persoz, a new proximate principle called diastase, which is formed during malting, in the grains of barley, oats, and wheat, and may be separated in a pure state, if we moisten the malt flour for a few minutes in cold water, press it out strongly, filter the solution, and heat the clear liquid in a water bath, to the temperature of 158°. The greater part of that albuminous azotized substance is thus coagulated, and is to be separated by a fresh filtration ; after which, the clear liquid is to be treated with alcohol, when a flocky precipitate appears, which is diastase. To pu- rify it still further, especially from the azotized matter, we should dissolve it in water, and precipitate again with alcohol. When dried at a low temperature, it appears as a solid white substance, which contains no azote ; is insoluble in alcohol, but dissolves in water and proof spirit. Its solution is neutral and tasteless ; when left to itself, it changes with greater or less rapidity according to the temperature, and becomes sour at a temperatiu^e of from 149° to 167°. It has the property of converting starch into gum (dextrine) and sugar, and indeed, when sufficiently pure, with such energy that one part of it disposes 2000 parts of dry starch to that change, but it operates the quicker the greater its quantity. Whenever the solution of diastase with starch or with dextrine is heated to the boiling point, it loses the sugar-fermenting property. One hundred parts of well-malted starch appear to contain about one part of this substance. We can now understand the theory of malting, and the limits between which the temperature of the liquor ought to be maintained in this operation ; namely, the rau«»e between 157° and 160° F. It has been ascertained as a principle in mashins, that the best and soundest extract of the malt is to be obtained, first of all, by beginning to work with water at the lowest of these heats, and to conclude the mash with water at the highest. Secondly, not to operate the extraction at once with the whole of the water that IS to be employed ; but with separate portions and by degrees. The first portion is added with the view of penetrating equally the crushed malt, an! of extracting the already furmeJ sugar ; the next for efl'ecting the sugar fermentation by the action of the diastase. By this means, also, the starch is not allowed to run into a cohesive paste and the extract IS more easily drained from the poorer mass, and comes ofl" in the form of a nearly limpid wort. The thicker, moreover, or the less diluted the mash is, so much the easier is the wort fined in the boiler or copper by the coagulation of the albuminous matter: these principles illustrate, in every condition, the true mode of c-mviuctine the mashing process ; but different kinds of malt require a different treatrarat. Pale and slightly kilned malt requires a somewhat lower heat than malt highly kilned, because the former has more u-decomposed starch, and is more ready to become pasty. The ionner also, for the same reason, needs a more leisurely infusion than the latter, for its conv-ersion into mucilaginous susar. The more sugar the malt contains, the more is its saccharine fermrntation accelerated by the action of the diastase. What has been here said of pale malt is still more applicable to the case of a mixture of raw grain with malt, tor It requires still gentler heats, and more cautious treatment. •^K- V • ,, ^P^^lj-J'i'* is a Jarge circular tub with a double bottom ; the uppermost of Which IS called a false bottom, and is pierced with many holes. There is a space of about Jaa '"''• t^'^^e" the two, into which the stopcocks enter, for letting m the water and drawing oflf the wort. The holes of the false bottom should be burned, and not bored^ 134 BEER. BEER. 185 -.--i to prevent the chance of their filling up by the swelling of the wood, which would obstruct the drainage : the holes should be conical, and largest below, being about | of an inch there, and | at the upper surface. The perforated bottom must be fitted truly at the sides of the mash-tun, so that no grains may pass through. The mashed liquor is let off into a large back, from which it is pumped into the wort coppers. The mash-tun is provided with a peculiar rotatory apparatus for agitating the crushed grains and water together, which we shall presently describe. The size of the wort copper is proportional to the amount of the brewing, and it must, in general, be at least so large as to operate upon the whole quantity of wort made from one mashing ; that is, for every quarter of malt mashed, the copper should contain 140 gallons. The mash-tun ought to be at least a third larger, and of a conical form, somewhat wider below than above. The quantity of water to be employed for mashing, or the extraction of the wort, de- pends upon the greater or less strength to be given to the beer. The seeds of the crushed malt, after the wort is drawn off, retain still about 32 gallons of water for every quartei of malt. In the boiling, and evaporation from the coolers, 40 gallons of water are dis- sipated from one quarter of malt ; constituting 72 gallons in all. If 13 quarters of barley be taken to make 1500 gallons of beer, 2400 gallons of water must therefore be required (or the mashing. This example will give an idea of the proportions for an ordinary quality of beer. When the mash is to begin, the copper must be filled with water, and heated. As soon as the water has attained the heat of 145° m summer, or 167° in winter, 600 gallons of it are to be run off into the mash-tun, and the 13 quarters of crushed malt are to be gradu- ally thrown in and well intermixed by proper agitation, so that it may be uniformly moistened, and no lumps may remain. After contj.iuing the agitation in this way for one half or three quarters of an hour, the water in the copper will have approached to its boiling point, when 450 gaUons at the temperature of about 200° are to be run into the mash-tun, and the agitation is to be renewed till the whole assumes an equally fluid state : the tun is now to be well covered for the p^eser^'ation of its heat, and to be allowed to remain at rest for an hour, or an hour and a half. The mean temperature of this mash may be reckoned at about 145°. The time which is necessary for the trans- muting heat of the remaining starch into sugar depends on the quality of the malt. Brown malt requires less time than pale malt, and still less than a mLxture with raw grain, as already explained. After the mash has rested the proper time, the tap of the tun is opened, and the clear wort is to be drawn out into the under back. If the wort that first flows is turbid, it must be returned into the tun, till it runs clear. The amount of this first wort may be about 675 gallons. Seven hundred and fifty gallons of water, at the temperature of 200°, are now to be introduced up through the drained malt, into the tun, and the mixture is to be agitated till it becomes uniform, as before. The mash- tun is then to be covered, and allowed to remain at rest for an hour. The temperature of this mash is from 167° to 174°. While the second mash is making, the worts of the first are to be pumped into the wort copper, and set a-boiling as speedily as possible. The wort of the second mash is to be drawn off at the proper time, and added to the copper as fast as it wiU receive it, without causing the ebullition to stop. A third quantity of water amounting to 600 gallons, at 200°, is to be introduced into the mash-tun, and after half an hour is to be drawn off, and either pumped into the wort copper, or reserved for mashing fresh malt, as the brewer may think fit. The quantity of extract, per barrel weight, which a quarter of malt yields to wort, amounts to about 84 lbs. The wort of the first extract is the strongest ; the second con- tains, commonly, one half the extract of the first ; and the third, one half of the second ; according to circumstances. To measure the degrees of concentration of the worts drawn off from the tun, a par- ticular form of hydrometer, called a saccharometer, is employed, which indicates the number of pounds weight of liquid contained in a barrel of 36 gallons imperial measure. Mow, as the barrel of water weighs 360 lbs., the indication of the instrument, when placed in any wort, shows by how many pounds a barrel of that wort is heavier than a barrel of water; thus, if the instrument sinks with its poise till the mark 10 is upon a line with the surface of the liquid, it indicates that a barrel of that wort weighs ten pounds more than a barrel of water. See Saccharometer. Or, supposing the barrel of wort weighs 396 lbs., to convert that number into specific gravity, we have the following simple rule : — 360:396 :: 100 : MOO; at which densify, by my experiments, the wort contains 25 per cent, of solid extract. Having been employed to make experiments on the density of worts, and the ferment- ative changes which they undergo, for the information of a committee of the House of Commons, which sat in July and August, 1830, I shall here introduce a short abstract o( that part of my evidence which bears upon the present subject. Mr first object was to clear up the di/ficulties which, to common apprehension, hung over the matter, from the difference in the scales of the sacc'aarometers m. use among the brewers and distillers of England and Scotland. I found that one quarter of good malt would yield to the porter-brewer a barrel Imperial measure of wort, at the conctnfrated specific gravity of 1*234. Now, if the decimal part of this number be multiplied by 360, being the number of pounds weight of water in the barrel, the product will denote the excess in pounds, of the weight of a barrel of such concentrated wort, over that of a barrel of water ; and that product is, in the present case, 84*24 pounds. Mr. Martineau, jun., of the house of Messrs. Whitbread and Company, and a eentlc- man connected with another great London brewery, had the kindness to inform me that their average product from a quarter of malt was a barrel of 84 lbs. gravity. It is ob- vious, therefore, that by taking the mean operation of two such great establishments, I must have arrived very nearly at the truth It ought to be remarked that such a high density of wort as 1*234 is not the result of any direct experiment in the brewery, for infusion of malt is never drawn off so strong; that densiiy is deduced by computation from the quantity and quality of several succes- sive infusions ; thus, supposing a first infusion of the quarter of malt to yield a barrel of specific gravity 1*112, a second to yield a barrel at 1-091, and a third a barrel at 1*031, we shall have three barrels at the mean of these three numbers, or one barrel at their sum, equal to 1*234. I may here observe that the arithmetical mean or sum is not the true mean or sum of the two specific gravities ; but this difference is either not known or disregarded by the brewers. At low densities this difference is inconsiderable, but at high densities it would lead to serious errors. At specific gravity 1-231, wort or sirup contains one half of its weight of solid pure saccharum, and at 1*1045 it contains one fourth'of its weight; but the brewer's rule, when here applied, gives for the mean specific gravity 1*1155= ^t : The contents in solid saccharine matter at that density are however 27^ per cent., showing the rule to be 2\ lbs. wrong in excess on 100 lbs., or 9 lbs. per barrel. The specific gravity of the solid dry extract of malt wort is 1*264 ; it was taken in oil of turpentine, and the result reduced to distilled water a^ unity. Its specific volume is 0*791 1, that is, 10 lbs. of it will occupy the volume of 7*911 lbs. of water. The mean specific gravity, by computation of a solution of that extract in its own weight of water, is 1*1166; but by experiment, the specific gravity of that solution is 1*216, showing considerable condensation of volume in the act of combination with water. The following Table shows the relation between the specific gravities of solutions of malt extract, and the per-centage of solid extract they contain : Extr Malt. Water. Malt Extract in 100. Sugar in 100. Specific gravity. 600 H - 600 50-00 4700 1-2160 600 -J - 900 40*0 37-00 M670 600 - 1200 33-3 31-50 M350 600 - 1500 28*57 26-75 1- 11.30 600 J — 1800 25-00 24*00 1*1000 The extract of malt was evaporated to dryness, at a temperature of about 250® F., without the slightest injury to its quality, or any empvreumatic smell. Bate's tables have been constructed on solutions of sugar, and not with solutions of extract of malt, or they agree sufficiently well with the former, but differ materially from the latter. Allan's tables give the amount of a certain form of solid saccharine matter extracted from malt, and dried at 175° F., in correspondence to the specific gravity of the solution; but I have found it impossible to make a solid extract from infusions of malt, except at much higher temperatures than 175° F. Indeed, the numbers on Allan's saccharometei scale clearly show that his extract was by no means dry: thus, at 1*100 of gravity he assigns 29*669 per cent, of solid saccharine matter ; whereas there is at that density of solid extract only 25 per cent. Again, at M35, Allan gives 40 parts per cent, of soUd extract, whereas there are only 33 1 present. By the triple mashing operations above described, the malt is so much exhausted that It can 5Meld 110 further extract useful for stron- beer or porter. A weaker wort might no doubt still be drawn off for small beer, or for contributing a little to the strength of the next mashing of fresh malt. But this I beUeve is seldom practised bv respectable brewers, as it impoverishes the grains which they dispose of for feeclin? cattle. 1 he wort should be transferred into the copper, and made to boil as soon as possible, lor If It remains long m the under-back it is apt to become acedcent. The steam more- over raised from it m the act of boiHns serves to screen it from the oxv-enating or acidi- tymg influence of the atmosphere. UntU it begins to boU, the air should be excluded by some kind of a cover. 136 BEER. BEER. 13T . ! t I ■! li Sometimes the first wort is brewed by itself into strong ale, the second by itself into an in termed iate quality ; and the third into small beer ; but this practice is not much fol- lowed in this country. We shall now treat of the boiling in of the hops. The wort drawn from the mash- tun, whenever it is pumped into the copper, must receive its allowance of hops. Besides evaporating off a portion of the water, and thereby concentrating the wort, boiling has a twofold object. In the first place, it coagulates the albuminous matter, partly by the heat, and partly by the principles in the hops, and thereby causes a general clarification of the whole mass, with the effect of separating the muddy matters in a flocculent form. Secondly, during the ebullition, the residuary starch and hordeine of the malt are con- verted into a limpid sweetish mucilage, the dextrine above described ; while some of the glutinous stringy matter is rendered insoluble by the tannin principle of the hops, which favors still further the clearing of the wort. By both operations the keeping quality of the beer is improved. This boil must be continued during several hours ; a longer time for the stronger, and a shorter for the weaker beers. There is usually one seventh or one sixth part of the water dissipated in the boiling copper. This process is known to have cont»'^ued a sufficient time, if the separation of the albuminous flocks is distinct, and if these are found, by means of a proof gauge suddenly dipped to the bottom, to be collected there, while the supernatant liquor has become limpid. Two or three hours* boil is deemed long enough in many well-conducted breweries ; but in some of those in Belgium, the boiling is continued from 10 to 15 hours, a period certainly detrimental to the aroma derived from the hop. Many prefer adding the hops when the wort has just come to the boiling point. Their effect is to repress the further progress of fermentation, and especially the passage into the acetous stage, which would otherwise inevitably ensue in a few days. In this respect, no other vegetable production hitherto discovered can be a substitute for the hop. The odorant principle is not so readily volatilized as would at first be imagined; for when hop is mixed with strong beer wort and boiled for many hours, it can still impart a very considerable degree of its flavor to weaker beer. By mere infusion ia hot beer or water, without boiling, the hop loses very little of its soluble principles. The tannin of the hop combines, as we have said, with the vegetable albumen of the barley, and helps to clarify the liquor. Should there be a deficiency of albumen and gluten, in consequence of the mashing having been done at such a heat as to have coagu- lated them beforehand, the defect may be remedied by the addition of a liille gelatine to the wort copper, either in the form of calf's foot, or of a little isinglass. If the hops be boiled in the wort for a longer period than 5 or 6 hours, they lose a portion of their fine flavor; but if their natural flavor be rank, a little extra boiling improves it. Many brew- ers throw the hops in upon the surface of the boiling wort, and allow them to swim there for some time, that the steam may penetrate them, and open their pores for a complete so- lution of their principles when they are pushed down into the liquor. It is proper to add the hops in considerable masses, because, in tearing them asunder, some of the lupuline powder is apt to be lost. The quantity of hop to be added to the wort varies according to the strength of the '>eer, the length of time it is to be kept, or the heat of the climate where it is intended to be sent. For strong beer, 4^ lbs. of hops are required to a quarter of malt, when it is to be highly aromatic and remarkably clear. For the stronger kinds of ale and porter, the rule, in England, is to take a pound of hops for every bushel of malt, or 8 lbs. to a quarter. Common beer has seldom more than a quarter of a pound of hops to the bushel of malt. It has been attempted to form an extract of hops by boiling m covered vessels, so as not to lose the oil, and to add this instead of the hop itself to the beer. On the great scale this method has no practical advantage, because the extraction of the hop is per- fectly accomplished during the necessary boiling of the wort, and because the hop ope- rates very beneficially, as we have explained, in clarifying the beer. Such an extract, moreover, coulJ be easily adulterated. Of the Coolers. — The contents of the copper are run into what is called the hop- back, on the upper part of which is fixed a drainer, to keep bac'i the hops. The pump is placed in the hop-back, for the purpose of raising the wort to the coolers, usually placed in an airy situation upon the top of the brewery. Two coolers are indispensable when we make two kinds of beer from the same brewing, and even lo single brewings, called gyles, if small beer is lo be made. One of these coolers ought to be placed above the level of the other- As it is of great consermence to cool the worts down to the fermenting pitch as fast as possible, various contrivances have been made for effecting this purpose. The common c(X>ler is a square wooden cistern, about 6 inches deep, and of such an extent of surface that the whole of one boil may only occupy 2 inches, or thereabouts, of depth in it. For a quantity of wort equal to about 15D0 gallons its area should be at least 54 feet long and 20 feet wide. The seams of the cooler must be made perfectly water-tight and smooth, so that no liquor may lodge in them when they are emptied. The utmost cleanliness is required, and an occasional sweetening with lime-water. The hot wort reaches the cooler at a temperature of from 200° to 208°, according to the power of the pump. Here it should be cooled to the proper temperature for the fermenting tun, which may vary from 54° to 64°, acccrding to circumstances. The refrigeration is accomplished by the evaporation of a porJon of the liquor: it is more ra]iid in proportion to the extent of the surface, to the low temperature, and the dryness of the atmosphere surrounding the cooler. The renewal of a body of cool dry air by the agency of a fan, may be employed with great advantage. The cooler itself must be so placed that its surface shall be freely exposed to the prevailing wind of the district, and be as free as possible from the eddy of surrounding buildings. It is thought by many that the agitation of the wort during its cooling is hurtful. Were the roof made move^ able, so that the wort could be readily exposed, in a clear night, to the aspect of the sky, it would cool rapidly by evaporation, on the principles explained by Dr. Wells, in his " Essay on Dew." When the cooling is effected by evaporation alone, the temperature falls very slowly, even in cold air, if it be loaded with moisture. But when the air is dry, the evaporation is vigorous, and the moisture exhaled does not remain incumbent on the liquor, as in damp weather, but is diffused widely in space. Hence we can understand how wort cools so rapidly in the spring and autumn, when the air is generally dry, and even more quickly than in winter, when the air is cooler, but loaded with moisture. In fact, the cooling process goes on better when the atmosphere is from 50° to 55°, than when it falls to the freezing point, because in this case, if the air be still, the vapors generated remain on the surface of the liquor, and prevent further evaporation. In summer the cooling can take place only during the night. In consequence of the evaporation during this cooling process, the bulk of the worts is considerably reduced ; thus, if the temperature at the beginning was 208°, and if it be at the end 64°, the quantity of water necessary to be evaporated to produce this refrigeration would be nearly | of the whole, putting radiation and conduction of heat out of the question. The effect of this will be a proportional concentration of the beer. The period of refrigeration in a well-constructed cooler, amounts to 6 or 7 hours in favorable weather, but to 12 or 15 in other circumstances. The quality of the beer is much improved by shortening this period ; because, in consequence of the great surface which the wort exposes to the air, if: readily absorbs oxsyen, and passes into the acetous fermentation with the production of various mouldy spots ; an evil to which ill-hopped beer is particularly liable. Various schemes have been contrived to cool wort, bv trans- mitting it through the convolutions of a pipe immersed in cold water. The best plan is to expose the hot wort for some hours freely to the atmosphere and the cooler, when the loss of heat is most rapid by evaporation and other means, and when the tempera- ture falls to 100°, or thereby, lo transmit the liquor through a zig-zag pipe, laid almost horizontally in a trough of cold water. The various methods described under Refrif^era- ior are more complex, but they may be practised in many situations with considerable ad- vantage. Whilst the wort reposes in the cooler, it lets fall a slight sediment, which consists partly of fine flocks of coagulated albumen combined with tannin, and partly of starch, which had been dissolved at the high temperature, and separates at the lower. The wort should be perfectly limpid, for a muddy liquor never produces transparent beer. Such beer contains, besides mucilaginous sugar and gum, usually some starch, which even re- mains afier the fermentation, and hinders its clarifyins, and gives it a tendency to sour. i!f 7^^^ contains more starch the hotter it has been mashed, the less hops have been added, and the shorter time it has been boiled. The presence of starch in the wort mav be made manifest by adding a little solution of iodine in alcohol to it, when it will be'- come immediately blue. We thus see that the tranquil cooling of wort in a proper ves- sel has an advantage over cooling it rapidly bv a refrigeratory apparatus. When the wort is sufficiently cool, it is let down into the fermenting tun. In this transfer the cool- ing might be carried several degreo:* lower, were the wort made to pass down through p tube enclosed m another tube, along which a stream of cold water is flowing in the cppo- site direction, as we have described in the sequel of Acetic acid. These ft.rmenting tuns are commonly called gyle-tuns, or working tuns, and are either square or circular, the latter being preferable on many accounts. IV. 0/the Fermentation —in the great London breweries, the size of these fermenting tuns is such that they contain from 1200 to 1500 barrels. The quantity of wort intrcKluced at a time must, however, be considerably less than the capaciiv of the vessel to allow room for the head of yeast which rises during the process; if the vessel be cylindrical, this head is proportional to the depth of the worts. In certain kinds of 138 BEER. BEER. 139 i ■ 11 't I M HI \ l\ 'I ■ 1 : I ;! ! ; i :! Jt t :i fermentation, it may rise to a third of that depth. In general, the fermentation proceeds* more uniformly and constantly in large masses, because they are little influenced by vi- cissitudes of temperature ; smaller vessels, on the other hand, are more easily handled. The general view of fermentation will be found under that title ; I shall here make a few remarks on what is peculiar lo beer. During the fermentation of wort, a portion of its saccharine matter is converted into alcohol, and wort thus changed is beer. It is necessary that this conversion of the sugar be only partial, for beer which contains no undecomposed sugar would soon turn sour, and even in the casks its alcohol undergoes a slow fermentation into vinegar. The amount of this excess of sugar is greater in proportion to the strength of the wort, since a certain quantity of alcohol, already formed, prevents the operation of the ferment on the remaining "vort. Temperature has the greatest influence upon the fermentation of wort. A temperature of from 55° to 60" of the liquor, when that of the atmosphere is 55°, is most advantageous for the commencement. The warmth of the wort as it comes into the g)'le-tun must be modi- fied by that of the air in the apartment. In winter, when this apartment is cold, the wort should not be cooled under 64° or 60°, as in that case the fermentation would be tedious or interrupted, and the wort liable to spoil or become sour. In summer, when the temperature of the place rises to above 75°, the wort should be cooled, if possible, down to 65°, for wliich purpose it should be let in by the system of double pipes, above mentioned. The liigher the temperature of the wort, the sooner will the fermentation begin and end, and the less is it in our power to regulate its progress. The expert brewer must steer a middle course between these two extremes, which threaten to de- stroy his labors. In some breweries a convoluted pipe is made to traverse or go round the sides of the gyle-tun, through which warm water is allowed to flow in winter, and cold in summer, so as to modify the temperature of the mass to the proper fermenting pitch. If there be no contrivance of this kind, the apartment may be cooled in summer, by suspending wet canvass opposite the windows in warm weather, and kindling a small Slove within it in cold. When the wort is discharged into the gyle-tun, it must receive its dose of yeast, which has been previously mixed with a quantity of the wort, and left in a warm place till it has begun to ferment. This mixture, called lobb, is then to be put into live tun, and stir- red well through the mass. The yeast should be taken from similar beer. Its quantity must depend upon the temperature, strength, and quantity of the wort. In general, one gallon of yeast is sufficient to set 100 gaUons of wort in complete fermentation. An ex- cess of yeast is to be avoided, lest the fermentation should be too violent, and be finished in less than the proper period of 6 or 8 days. More yeast is required in winter than in summer; for, at a temperature of 50°, a double quantity may be used to that at 68°. Six or eight hours after adding the yeast, the tun being meanwhile covered, the fer- mentation becomes active : a white milky-looking froth appears, first on the middle, and spreads gradually over the whole surface ; but continues highest in the middle, forming a frothy elevation, the height of which increases with the progress of the fermentation, and whose color gradually changes to a bright brown, the result, apparently, of the oxy- dation of the extractive contained in this yeasty top. This covering screens the wort from the contact of the atmospherical air. During this time, there is a perpetual disen- gagement of carbonic acid gas, which is proportional to the quantity of sugar converted into alcohol. The warmth of the fermenting liquid increases at the same time, and is at a maximum when the fermentation has come to its highest point. This increase of temperature amounts to from 9° to 14° or upwards, and is the greater the more rapid the fermentation. But in general, the fermentation is not allowed to proceed so far in the gyle-tun, for after it is advanced a lillle way, the beer is cleansedy that is, drawn off into other vessels, which are large barrels set on end, with large openings in their top, fur- nished with a sloping tray for discharging an excess of yeast into the wooden trough, in which the stillions stand. These stillions are placed in communication with a stcre-tub, which keeps them always full, by hydrostatic pressure, so thai the head of yeast may spontaneously flow over, and keep the body of liquor in the cask clean. This apparatus will be explaineJ in describing the brewery plant. See the Jipuresy infra. It must be observed, that the quantity of yeast, and the heal of fermentation, differ foi every difl'erent quality of beer. For mild ale, when the fermentation has reached 75° its first flavor begins; at 80° the flavor increases; at 85° it approaches the high flavor; at 90° it is high; but it may be carried to 100° and upwards, for particular purposes. A wort of 301bs. per barrel (sp. gr. 1'088), ought to increase about 15*, so that in order to arrive at 80°, it should be set at 65°. The quantity of yeast for such an ale should be from 2 to 3 lbs. per barrel. The higher Ihe heat, the less yeast is ne- cessary. If the heat of the fermeniatiuu should at any time fall, it must be raised by a oupply of fresh yeast, well stirred in; but this practice is not advisable in general, because rousing the worts in the gyle-tun is apt to communicate a rank flavor of yeast to the ale. It is the practice of many experienced brewers to look every 2 hours into the pyle-tun, chiefly with the view of obserx'^ing the progress of the heat, which is low at first, but afterwards often increases half a degree per hour, and subsequently decline?, as the fermentation approaches its conclusion, till at length the heat becomes' uniform, or sometimes decreases, before the fermentation is finished, especially where the quantity operated upon is small. Some brewers recommend, when the fermentation is carried to its utmost period, to add about 7 lbs. of wheat or bean flour to a gyle-tun of 25 or 30 barrels, at the time of dean- sivgy so as to quicken the discharge of the yeast, by disengagement cf more carbonic acid. The flour should be whisked up in a pail, with some of the beer, till the lumps are bro- ken, and then poured in. By early cleansing, the yeast is pieserved longer in a state prie-tun. The third drawn wort, with the remaining half of the second, is then boiled with the same hops, saved by the drainer, and, after cooling, added to the former in the gyle-tun, when the two must be well roused together. It is obvious, from the preceding development of principles, that all amylaceous and saccharine materials, such as potatoes, beans, turnips, as well as cane and starch sirup, molasses, &c., may be used in brewing beer. When, however, a superior quality of brown beer is desired, malted barley is indispensable, and even with these substitutes a mixture of ii is most advantageous. The washed roots of the common carrot, of the red and yellow beet, or of the potato, must be first boiled in water, and then mashed into a pulp. This pulp must be mixed with water in the copper, along with wheaten or oat meal, and the proper quantity of hops, then boiled during 8 or 9 hours. This wort is to be cooled in the usual way, and fermented, with the addition of yeast. A much better process is that now practised, on a considerable scale, at Strasbourg, in making the ale, for which that city i-s celebrated. The mashed potatoes are mixed with from a twentieth to a tenth of their weight of finely ground barley malt, and some water. The mixture is exposed, in a water- bath, to a heat of 160* F. for four hours, whereby it passes into a saccharine state, and may then be boiled with hops, cooled, and properly fermented into good beer. Maize, or Indian corn, has also been employed to make beer ; but its malting is somewhat difficult on account of the rapidity and vigor with which its radicals and plumula sprout forth. The proper mode of causing it to germinate is to cover it, a few inches deep, with common soil, in a garden or field, and to leave it there till the bed is covered with green shoots of the plant. The corn must be then lif\ed, washed, and exposed to the kiln. The Difference of the Fermentation. — ^The greater or less rapidity with which the worts are made to ferment has a remarkable influence upon the quality of the beer, especially in reference to its fitness for keeping. The wort is a mucilaginous solution in which the yeasty principles, eliminated by the fermentation, will, if favored by regular and slow intestine movements, completely rise to the surface, or sink to the bottom, so as to leave the body fine. But, when the action is too violent, these barmy glutinous matters get comminuted and dispersed through the liquor, and can never after- wards be thoroughly separated. A portion of the same feculent matter becomes, moreover, permanently dissolved, during this furious commotion, by the alcohol that is generated. Thus the beer loses not merely its agreeable flavor and limpidity, but is apt to spoil from the slightest causes. The slower, more regularly progressive, and less interrupted, therefore, the fermentation is, so much better will the product be. Beer, in its perfect condition, is an excellent and healthful beverage, combining, in some measure, the virtues of water, of wine, and of food, as it quenches thirst, stimulates, cheers, and strengthens. The vinous portion of it is the alcohol, proceeding from the fermentation of the malt sugar. Its amount, in common strong ale or beer, is about 4 per cent., or four measures of spirits, specific gravity 0*825 in 100 measures of the liquor. The best brown stout porter contains 6 per cent., the strongest ale even 8 per cent. ; but common beer only one. The nutritive part of the beer is the undecomposed gum-sugar, and the starch-gum, not changed into sugar. Its quantily is very variable, accordmg to the original starch of the wort, the length of the fermentation, and the ag« of the beer. The main feature of good beer is fine color and transparency ; the production of which is an object of great interest to the brewer. Attempts to clarify it in the cask seldom fail to do it harm. The only thing that can be used with advantage for fimng foul or muddy beer, is isinglass. For porter, as commonly brewed, it is frequently had recourse to. A pound of good isinglass will make about 12 gallons o^ finings. It is cut into slender shreds, and put into a tub with as much vinegar or hard beer as will cover it, in order that it may swell and dissolve. In proportion as the solution proceeds, more beer must be poured upon it, but it need not be so acidulous as the first, because, when once well softened by the vinegar, it readily dissolves. The mixture should be frequently agitated with a bundle of rods, till it acquires the uniform consistence of thin treacle, when it must be equalized still more by passing through a tammy cloth, or a sieve. It may now be made up with beer to the proper measure of dilution. The quantity generally used is from a pint to a quart per barrel, more or less, according to the foulness of the beer. But before putting it into the butt, it should be diflfused through a considerable volume of the beer with a whisk, till a frothy head be raised upon it. It is in this state to be poured into the cask, briskly stirred about ; afler which the cask must be bunged down for at least 24 hours, when the liquor should be limpid. Sometimes the beer will not be improved by this treatment ; but this should be ascertained beforehand, by drawing off some of the beer into a cylindric jar or vial, and adding to it a little of the finings. After shaking and setting down the glass, we shall observe whether the feculencies begin to collect in flocky parcels, which slowly subside ; or whether the isinglass falls to the bottom without making any impression upon the beer. This is always the case when the fermentation is incomplete, or a se- condary decomposition has begun. Mr. Jackson has accounted for this clarifying eflfect of isinglass in the following way. The isinglass, he thinks, is first of all rather diffused mechanically, than chemically dissolved, in the sour beer or vinegar, so that when the finings are put into the foul beer, the gelatinous fibres, being set free in the liquor, attract and unite with the floating fecu- lencies, which before this union were of the same specific gravity with the beer, and therefore could not subside alone ; but having now acquired additional weight by the coating offish glue, precipitate as a flocculent magma. This is Mr. Jackson's explana- tion ; to which I would add, that if there be the slightest disengagement of carbonic acid gas, it will keep up an obscure locomotion in the particles, which will prevent the said light impurities, either alone or when coated with isinglass, from subsiding. The beer is then properly enough called stubborn by the coopers. Bui the true theory of the action of isinglass is, that the tannin of the hops combines with the fluid gelatine, and forms a flocculent mass, which envelopes the muddy particles of the beer, and carries them to the bottom as it falls, and forms a sediment. When, aAer the finings are poured in, no proper precipitate ensues, it may be made to appear by the addition of a little decoction of hop. Mr. Richardson, the author of the well-known brewer's saccharometer, gives the following as the densities of different kinds of beer : — Beer. Pounds per Barrel. Specific Giavity. Burton ale, 1st sort - - - 40 to 43 1-111 to M20 2d ditto - 35 to 40 1«097 to Mil 3d ditto - - - 28 to 33 1-077 to 1-092 Common ale - 25 to 27 1-070 to 1-073 Ditto ditto 21 1-058 Porter, common sort 18 1-050 Ditto, double - - - - 10 1-055 Ditto, brown stout - - - S3 1-064 Ditto, best brown stout 26 1-072 Common small beer - - • 6 1-014 Good table beer - - - - 12 to 14 1-033 to 1 039 0/ Returns or Malt Residuums. — When small beer is brewed afler ale or porter, only one mash is to be made ; but where this is not done, there may be two mashes, in order to economize malt to the utmost. We may let on the water at 160° or 165°, in any convenient quantity, infuse for an hour or thereby, then run it off, and pump into the copper, putting some hops into it, and causing it to boil for an instant; when it may be transferred to the cooler. A second mash or return may be made in the same manner, but at a heat 5° lower ; and then disposed of in the boiler with some hops, which may remain in the copper during the night at a scalding heat, and may be discharged intfc the cooler in the morning. These two returns are to be let down into the under- back immediately before the next brewing^ and thence heated in the copper for the next J '• k 142 BEER. mashin- of fresh malt, instead of hot water, commonly called liquoTy in the breweries. BS^wancTmuTt bi made, in the calculation of the worts, for the quantity of ferment- able matter in these two returns. The nelt aggregate savmg is estimated from the SIvitTrtheret^ntrn when cold in t^ cooler A slight economy is also made in Se extra boiling of the used hops. The lapse of a day or two between the consecutive brewings iTno Objection to the method of retur.^, because they are too weak m saccha. rinp matter to run any risk of fermentation. , , . .v In concluslo^ it may be remarked that Mr. Richardson somewha underrates the irravitv of ^rter which is now seldom under 201bs. per barrel. The criterion lor trans- ^rln' frort^e btiuV't o the cleansing butts is the attenuation caused by the produc tion of a cohol in the beer : when that has fallen to lOlbs. or 1 libs., which it usua y does 111 48 hou7s the cleansing process is commenced. The heat is at this time generally 7o% if it was pitched at 65" ; for the heat and the attenuation go hand in hand. About thirty years ago, it was customary for the London brewers of porter to keep immense stocks of it for eighteen months or two years, with the view of improving its oualitv The beer was pumped from the cleansing butts mto store-vats, holdmg from twenty to twenty-five gvles or brewings of several hundred barrels each. The store-vats had commonly a capacity of 5000 or 6000 barrels; and a few were double, and one was trebK this size. The porter, during its long repose m these vats, became hne, and by obscure fermentation its saccharine mucUage was nearly all converted into vinous liquor, and dissipated in carbonic acid. Its hop-bitter was also in a great degree decomposed. Good hard beer was the boast of the day. This was sometimes softened by the publican, by the addition of some mild new-brewed beer. Of late years, the taste of the metro- polis has undergone such a complete revolution in this respect, that nothing but the mildest porter will now go down. Hence, sLx weeks is a long period for beer to be kept in London : and much of it is drunk when only a fortnight old. Ale is for the simie rea- son come greatly into vogue; and the two greatest porter houses, Messrs. Barclay, Perkins & Co., and Truman, Hanbury, & Co., have become extensive and successful brewers of mild ale, to please the changed palate of their customers. We shall add a few observations upon the brewing of Scotch ale. This beverage is characterized by its pale amber color, and its mUd balsamic flavor. The bitterness of the hop is so mellowed with the malt as not to predominate. The ale of Preston Pans is in fact, the best substitute for wine which barley has hitherto produced. The low temperature at which the Scotch brewer pitches his fermenting tun restricts his labors to the colder months of the year. He does nothing during four of the summer months. He is extremely nice in selecting his malt and hops; the former being made from the best English barley, and the latter being the growth of Famham or East Kent. The yeast is carefuUy looked after, and measured into the fermenting tun m the proportion ol one gallon to 240 gallons of wort. , ^ . ... v ♦ ♦»,- Only one mash is made by the Scotch ale brewer, and that pretty strong ; but he malt is exhausted by eight or ten successive sprinklings of liquor (hot water) over the goods (malt), which are termed in the vernacular tongue, ^arge*. These waterings percolate through the malt on the mash-tun bottom, and extract as inuch of the saccharine matter as may be sufficient for the brewing. By this simple method much higher specific gravities may be obtained than would be practicable by a second mash. W ith malt, the infusion or saccharine fermentation of the diastase is finished with the first mash; and nothing remains but to wash away from the goods the matter which that process has rendered soluble. It will be found on trial that 20 barrels of wort drawn from a cerlam quantity of malt, by two successive mashings, wiU not be so rich m fermentable matter as 20 barrels extracted by ten successive sparges of two barrels each. 1 he grains always remain soaked with wort like that just drawn off, and the total residual quantity IS th^ee fourths of a barrel for every quarter of malt. The gravity of this residua wort will on the first plan be equal to that of the second mash ; but on the second plan, it will be equal only to that of the tenth sparge, and will be more attenuated in a very high geometrical ratio. The only serious objection to the sparging system is the loss ol time by the successive drainages. A mash-tun with a steam jacket promises to suit the sparging system well ; as it would keep up a uniform temperature m the goods, without requiring them to be sparged with very hot liquor. The first part of the Scotch process seems of doubtful economy; for the mash liquor is heated so^hi'-h as 180°. After mashing for about half an hour, or tiU every particle of the malt is thoroughly drenched, the tun is covered, and the mLxture left to infuse about three hours ; it is then drained off into the under-back, or preferably mto the wort *^^fter this wort is ran oflT, a quantity of liquor (water), at ISOP of heat, is sprinkled uniformly over the surlace of the malt; being first dashed on a perforated circular board, suspended horizontally over the mash-tun, wherefrom it descends like a shower V ., BEER. 143 upon the whole of the goods. The percolating wort is allowed to flow oflT, by three or more small stopcocks round the circumference of the mash-tun, to ensure the equal dif^ fusion of the liquor. The first sparge being run oflT in the course of twenty minutes, another similar one is aflused ; and thus in succession till the whole of the drainage, when mixed with the first mash-wcrt, constitutes the density adapted to the quality of the ale. Thus, the strong worts are prepared, and the malt is exhausted either for table beer, or for a return^ as pointed out above". The last sparges are made 5P or 6° cooler than the first. The quantity of hops seldom exceeds four pounds to the quarter of malt. The manner of boiling the worts is the same as that above described ; but the conduct of the fer- mentatifin is peculiar. The heat is pitched at 60°, and the fermentation continues from a fortnight to three weeks. "Were three brewings made in the week, seven or eight working tuns would thus be in constant action ; and, as they are usv.iriy in one room, and some of them at an elevation of temperature of 15°, the apartment must be pro- pitious to fermentation, however low its heat may be at the commencement. No more yeast is used than is indispensable ; if a little more be needed, ii is made efleclive by rousing up the tuns twice a day from the bottom. When the progress of the attenuation becomes so slack as not to exceed half a pound in the day, it is prudent to cleanse, otherwise the top-barm might re-enter the body of the beer, and it would become ymst-biiten. When the ale is cleansed, the head, which has not been disturbed for seme days, is allowed to float on the surface till the whole of the then pure ale is drawn off into the casks. This top is regarded as a sufiicient preservative against the contact of the atmosphere. The Scotch do not skim their tuns, as the Lon- don ale brewers commonly do. The Scotch ale, when so cleansed, does not require to be set upon close stilllons. It throws off little or no yeast, because the fermentation was nearly finished in the tun. The strength of the best Scotch ale ranges between 32 and 44 pounds to the barrel; or it has a specific gravity of from 1-088 to 1-122, according to the price at which it is sold. In a good fermentation, seldom more than a fourth of the original gravity of the wort remains at the period of the cleansing. Between one third and one fourth is the usual degree of attenuation. Scotch ale soon becomes fine, and IS seldom racked for the home market. The following table will show the progress of fermentation in a brewing of good Scotch ale : 20 barrels of mash-worts of 42^ pounds gravity = 860-6 20 — returns 6JU — i22 «iV 12 ) 982-6 Fermentation : — pounds weight of extract per quarter of rpalt = 81 March 24. pitched the tun at 51°: yeast 4 gallons. AprD 25. 28. 30. 1. 4. 6. 6. 7. 8. 9. 10. Temp. 62° 66° 60° 62» 65» 66* 67* 67* 66° 66° 64° Gravity. 41 pounds. 39 34 32 29 added 1 lb. of yeast 25 23 20 18 15 14-5 cleansed. * The following table shows the origin and the result of fennentaiion,*in a number of practical experiments : — Oiigiaal Gravity of the Worts. 1-0950 1-0918 1-0829 1-0862 1-0780 1-0700 1-1002 1 bB. per Barrel of Specific Gravity of Saccharine Matter. *^- *'- 88-75 85-62 78-125 80-625 73-75 65-00 93-75 the Ale. 1-0500 1-0420 1-0205 1-0236 1-0280 1-0285 1-0400 Lbs. per Barrel of Saccharine Matter. 40-25 38-42 16-87 20-00 24-25 25-00 36-25 Attenuation, or Sac- 'harum deconii>o8ed 0-478 0-552 0-787 0-757 0-698 0-615 0-613 * Bbbwikq (Society for diffusing Useful Knowledge), p. 156. 144 J 1 t ) BEER. Fermenlation T&Ue— continued. BEER. 146 Otiginal Gravity of the Worts. lh». per Banel of (specific Gmvity of Sacchariue Matter. the Ale. 1-1025 1-0978 1-0956 1-1130 1-1092 1-1171 1-1030 1-0660 95-93 91-56 89-37 105-82 102-187 110-00 96-40 61-25 1-0420 1-0307 1-0358 1-0352 1-0302 1-0400 1-0271 1-0214 Lbs. per Barrel of Saccharine Matter, 38-42 27-00 32-19 31-87 26-75 36-25 23-42 17-80 Attenuation, or S«c-1 harum decomposed.! neous, on account of the quantity of ^^^^^i^^J^'^^PXn.i^^^^^^^ o the saccharine matter tion. It must be likewise ;^^°;:L^f^^^^*^^7JJe a^^^^^^^^^ the fermented liquor, will be partly counteracted, by the eflect of the f^^^i^^^^^^^^^^^^^ ^^rt ; being greatest less to be used with Pjop^ety. management of the mashing, may be tested The good quality of the malt, and the "f.^^^'^^X succes diawn worts. With by the Quantity of saccharme matter ^^J";,^;^^'?."^ ,^j^^^^^^^ ^y a safety-bath heat this view, an aliquot portion of ^-*^^V thl„ m^^^^^^ tX its volume of sUong spirit to a nearly concrete consistence, ^^f^^^„^^"" ^^^^^ dLsoM^ the starch and other of wine. The truly saccharme ^^^^^.^^/^^f J'^,^^^,^^ may be determined by matters will be separated; jf ^^^ ^^^^^,,i*^,^ Pl^nirmuch^^^^^^^ method of filtration and evaporation Or an ^^.^^^^J^^^^^^^^^^^^ with the alcohol arriving at the same result ^^^^^ be, after agitating ^/^^ vi c determine in a tali glass cylinder, to allow the 'f,^'"^\J^^/^^\i°,^^^^^^^ additional density the specific gravity of the ^^P^J"'^^.^,^*.^ ?""^,\^„ quantTty of malt sugar which it ha. which the alcohol has acquired ^'^l fj^^^^ '^^ at the request of Henry Warburton, received. The foll«w^»S;^^l^'JT'^"'*^^^^,^I,:Tte; of th\ of Commons in 1830, Esq., M. P., chairman of the M^las^es Committee ^^ ^/^^^^^ the quantity in wUl Ihow the brewer the prmcip e ^^. ^^^^..^P'l'.^^Vg^^^^^^ of a gallon of spirit of dif- grains weight of sugar requisite to raise the speciti. gravity oi g f ferent densities to the gravity of water = 1-000 . iin^nifi.- Gravity of Grains ; Weight of Sugar in the Specific Uravity oi Gallon Inipeiial. 0-995 If 0-990 ^ ^ " 0-985 2-800 0-980 3-710 0-975 4-690 0-970 ^'^^^ 0-965 ^'^^^ 0-960 "^'O^O S.955 f 00 n.Qfio 9-310 r ♦!,•» 4oKi« Txrne to «;how the effect of saccharine matter m The immediate P«n>ose of this table was to show m^^^^^ of the distiller. But disguising the presence or amount of alcohol in he ^^^ taints o ^^ ^^^^_ a similar table might easily be ^^^^''^'^p^^^ would be shown by h )1 of 0-825, for example, the ^"^^J^^^^, ^^ f^m agitation with a certain (he increase of specific gravity ^'^^^J^ ^^^^^J^^^^^ consistence by a safety-pan, made on weight of the wort, mspissated to a nearly solid consisteny j^^^ quantities theVinciple of my Patent susar.pan(Se^^^^^^^^^ being lOOO.gram ^^^^^^l^^J ^'"^f^^^^^^ ^^^^^^T rerTeL't! of t'^i^lyTa^c^^^^^^^^^ by slbtra^ction, that of farinaceous matter present in it. . . Brewerv. — Ftss. 113 and 114 represent the Plan,Macl,l,.ery<.^U^^'^yfj^^^ the largest scale , m arrangement of the "'^■'5"' """ " . ,^.., {^^ elevation fig. 113 is in a great degree imp.- ^ roX'piane" u^n ^Mch U L" but the di^rent vessels .re arranged so .. w explain their uses most readily, and at the same time to preserve, as nearly as poasibk. the relative positions which are usually assigned to each in works of this nature. CO I mmms^^^^^^^^ cJfPllf ? V ' ^^ ®"PP^y °^ ^^^ brewery is stored in vast granaries or malt-lofts, usuallf ^n?v 1 »n the upper part of the buildings. Of these, I have been able to repre^ oniy one, at a, Jig, 113 : the others, which are supposed to be on each side of it, cannot 146 BEER. BEER. ur II i l!fi be seen in this view. Immediately beneath the granary A, on the giound floor, is the mill ; in the upper story above it, are two pairs of rollers, ^g«. Ill, 112, and 113, under a, a, for bruising or crushing the grains of the malt. In the floor beneath the rollers are the mill-stones b, &, where the malt is sometimes ground, instead of being mcxely bruised by passing between the rollers, under a, a. The malt, when prepared, is conveyed by a trough into a chest tf, to the right of 6, from which it can be elevated by the action of a spiral screw, fig. 115, enclosed in the sloping lube e, into the large chest or bin b, for holding ground mall, situated imme- diately over the mash-tun d. The malt is reserved in this bin till wanted, and it is then let down into the mashing-tun, where the extract is obtained by hot water supplied from the copper g, seen to the right of b. The water for the service of the brewery is obtained from the well e, seen beneath the mill to the left, by a lifting pump worked by the steam engine ; and the forcing-pipe / of this pump conveys the water up to the large reservoir or water-back f, placed at the lop of the engine-house. From this cistern, iron pipes are laid to the copper g (on the right-hand side of the figure), as also to every part of the establishment where cold water can be wanted for cleaning and washing the vessels. The copper o can be filled with cold water by merely turning a cock ; and the water, when boiled therein, is conveyed by the pipe g into the bottom of the mash-tun d. It is introduced beneath a false bot- tom, upon which the malt lies, and, rising up through the holes in the false bottom, it extracts the saccharine matter from the malt ; a greater or less time being allowed for the infusion, according to circumstances. The instant the water is drawn off from the copper, fresh water must be let into it, in order to be ready for boiling the second mashing ; be- cause the copper must not be left empty for a moment, otherwise the intense heat of the fire would destroy its bottom. For the convenience of thus letting down at once as much liquor as will fill the lower part of the copper, a pan or second boiler is placed over the top of the copper, as seen in fig. 113; and the steam rising from the eopper communi- cates a considerable degree of heal to the contents of the pan, without any expense of fuel. This will be more minutely explained hereafter. (See fig. 117.) During the process of mashing, the malt is agitated in the mash-tun so as to expose every part to the action of the water. This is done by a mechanism contained within the mash-tun, which is put in motion by a horizontal shaft above it, h, leading from the mill. The mash machine is shown separately in fig. 116. When the operation of mash- ing is finished, the wort or extract is drained down from the malt into the vessel i, called the undn-back, immediately below the mash-tun, of like dimensions, and situated always on a lower level, for which reason it has received this name. Here the wort does not re- main longer than is necessary to drain off the whole of it from the tun above. It is then pumped up by the three-barrelled pump fe, into the pan upon the top of the copper, by a pipe which cannot be seen in this section. The wort remains in the pan until the water for the succeeding mashes is discharged from the copper. But this delay is no less of time, because the heat of the copper, and the steam arising from it, prepare the wort, which had become cooler, for boiling. The instant the copper is emptied, the first wort is let down from the pan into the copper, and the second wort is pumped up from the under-back into the upper pan. The proper proportion of hops is thrown into the cop- per through the near hole, and then the door is shut down, and screwed fast, to keep in the steam, and cause it to rise up through pipes into the pan. It is thus forced lo blow up through the wort in the pan, apd communicates so much heat to it, or water, called li- qiior by the brewers, that either is brought near to the boiling point. The different worts succeed each other through all the different vessels with the greatest regularity, so that there is no loss of time, but every part of the apparatus is constantly employed. When the ebullition has continued a sufficient period to coagulate the grosser part of the extract, and to evaporate part of the water, the contents of the copper are run off through a large cock into the jack-back k, below g, which is a vessel of sufficient dimensions to contain it, and provided with a bottom of cast-iron plates, perforated with small holes, through which the wort drains and leaves the hops. The hot wort is drawn off from the jack- back through the pipe h by the three-barrelled pump, which throws ii up to the coolers L, L, L ; this pump being made with different pipes and cocks of communication, to serve all the purposes of the brewery except that of raising the cold water from the well. The coolers l, l, l, are very shallow vessels, built over one another in several stages : and that part of the building in which they are contained is built with lattice- work or shutter flaps, on all sides, to admit free currents of air. When the wort is sufficiently cooled to be put to the first fermentation, it is conducted in pipes from all the different coolers to the large fermenting vessel or gyle-tun m, which, with another similar vessel behind it, is of suffi- cient capacity to contain £ill the beer of one day's brewings. Whenever the first fermentation is concluded, the beer is drawn off from the great fer- menting vessel M, into the small fermenting casks or cleansing vessels n, of which there are a great number in the brewery. They are placed four together, and to each four a com- 1 mon spout is provided to carry off the yeast, and conduct it into the troughs tt, placed beneath. In these cleansing vessels the beer remains till the fermentation is completed ; and it is then put into the store-vats, which are casks or tuns of an immense size, where it is kept till wanted, and is finally drawn off into barrels, and sent away from the brewery. The store-vats are not represented in the figure : they are of a conical shape, and of different dimen- sions, from fifteen to twenty feet diameter, and usually from fifteen to twenty feet in depth. The steam-engine which puts all the machine in motion is exhibited in its place, on the left side of the figure. On the axis of the large fly-wheel is a bevelled spur- wheel, which turns another si- milar wheel upon the end of a horizontal shaft, which extends from the engine-house to the great horse-wheel, set in motion by means of a spur-wheel. The horse-wheel drives all the pinions for the mill-stones 6 6, and also the horizontal axis which works the three-barrelled pump k. The rollers a, a, are turned by a bevel wheel upon the upper end of the axis of the horse-wheel, which is prolonged for that purpose; and the horizontal shaft h, for the mashing engine, is driven by a pair of bevel wheels. There is likewise a sack-tackle, which is not represented. It is a machine for drawing up the sacks of malt from the court-yard to the highest part of the building, whence the sacks are wheeled on » iruck to the malt-loft a, and the contents of the sacks are discharged. The horse-wheel is intended to be driven by horses occasionally, if the steam-engine should fail; but these engines are now brought to such perfection that it is very seldom any recourse of this kind is needed. Fig. 114 is a representation of the fermeniing house at the biewery of Messrs. Whitbread and Company, Chiswell Street, London, which is one of the most complete in its arrangement in the world : it was erected after the plan of Mr. Richardson, who con- ducts the brewing at those works. The whole of fig. 114 is to be considered as devoted to the same object as the large vessel m and the casks n, fig. 113. In fig. 114 r r is the pipe which leads from the different coolers to convey . the wort to the great fermenting tjessels or squares m, of which there are two, one behind the other ; // represents a part of vne great pipe which conveys all the water from the weU Eyfig. 113, up to the water cistern 'I !,!■ 1 :i! 148 BEER. p. This pipe is conducted purposely up the wall of the fennenting-house, ylg^. 114, and has a cock in it, near r, to stop the passage. Just beneath this passage a branch-pipe p proceeds, and enters a large pipe x a-, which has the former pipe r withinside of it. From the end of the pipe x, nearest to the squares m, another branch n n proceeds, and returns to the original pipe/, with a cock to regulate it. The object of this arrangement is to make all, or any part, of the cold water flow through the pipe z x, which surrounds the pipe r, formed only of thin copper, and thus cool the wort passing through the pipe r, until it is found by the thermometer to have the exact temperature which is desirable before it is put to ferment in the great square m. By means of the cocks at n and p, the quantity of cold water passing over the surface of the pipe r can be regulated at pleasure, whereby the heat of the wort, when it enters into the square, may be adjusted within half a degree. When the first fermentation in the squares m m is finished, the beer is drawn off from them by pipes marked v, and conducted by its branches w w w, to the different rows of fermenting-tuns, marked n n, which occupy the greater part of the building. In the hollow between every two rows are placed large troughs, to contain the yeast which they throw off. The figure shows that the small tuns are all placed on a lower level than the bottom of the great vessels m, so that the beer will flow into them, and, by hy- drostatic equilibrium, will fill them to the same level. When they are filled, the com- munication-cock is shut ; but, as the working off the yeast diminishes the quantity of beer in each vessel, it is necessary to replenish them from time to time. For this purpose, the two large vats o o are filled from the great squares m m, before any beer is drawn off into the small casks n, and this quantity of beer is reserved at the highei level for filling up. The two vessels o o are, in reality, situated between the two squares M M ; but I have been obliged to place them thus in the section, in order that they may be seen. Near each filling-up tun o is a small cistern t communicating with the tun o by a pipe, which is closed by a float-valve. The small cisterns / are always in communication with the pipes which lead to the small fermenting vessels n ; and there- fore the surface of the beer in all the tuns, and in the cisterns, will always be at the same level ; and as this level subsides by the working off of the yeast from the tnns, the float sinks and opens the valve, so as to admit a sufliciency of beer from tlie filling-up tuns o, to restore the surfaces of the beer in all the tuns, and also in the cistern /, to the original level. In order to carry off the yeast which is produced by the fermentation of the beer in the tuns o o, a conical iron dish or funnel is made to float upon the surface of the beer which they contain ; and from the centre of this funnel a pipe, o, descends, and passes through the bottom of the tun, being packed with a collar of leather, so as to be water-tight ; at the same time that it is at liberty to slide down, as the surface of the beer descends in the tun. The yeast flows over the edge of this funnel-shaped dish, and is conveyed down the pipe to a trough beneath. Beneath the fermenting-house are large arched vaults, p, built with stone, and lined with stucco. Into these the beer is let down in casks when suflUciently fermented, and is kept in store till wanted. These vaults are used at Mr. Whitbread's brewery, instead of the great store-vats of which we have before spoken, and are in some respects pre- ferable, because they preserve a great equality of temperature, being beneath the surface of the earth. The malt-rollers, or machines for bruising the grains of the malt, figs. Ill, 112, have been already described. The malt is shot down from a, fig. 113, the malt-lofl, into the hopper ; and from this it is let out gradually through a sluice or sliding shuttle, a, fig. 113, and falls between the rollers. Fig. 115, is the screw by which the ground or bruised malt is raised up, or conveyed from one part of the brewery to another, k is an inclined box or trough, in the centre of which the axis of the screw h is placed; the spiral iron plate or worm, which is fixed projecting from the axis, ZitA which forms the screw, is made very nearly to fill the inside of the box. By this means, when the screw is turned round by the wheels e f, or by any other means, it raises up the malt from the box d, and delivers it at the spout g. This screw is equally applicable for conveying the malt horizontally in the trough k, as slantingly ; and similar machines are employed in various parts of breweries for con- veying the malt wherever the situation of the works requires. Fig. 116, is the mashing-machine. a a is the tun, made of wood staves, hooped to- gether. In the centre of it rises a perpendicular shail, b, which is turned slowly round by means of the bevelled wheels t u at the top. c c are two arms, projecting from that axis, and supporting the short vertical axis d of the spur-wheel x, which is turned by the spur-wheel w; so that, when the central axis b is made to revolve, it will carry the thick short axle d round the tun in a circle. That axle d is furnished with a number of arms, e e, which have blades placed obliquely to the plane of their BEER. 149 motion. When the axis is turned round, these arms agitate the malt in the tun, and give it a constant tendency to rise upward from the bottom. The motion of the axle d is produced by a wheel, x, on the upper end of it, which it ^^^^fe^>>r^? :^^^;— -cT^ turned by a wheel, ir, fastened on the middle of the tube 6, which turns freely round upon its central axis. Upon a higher point of the same tube 6 is a bevel wheel, o, receivmg motion from a bevel wheel, q, fixed upon the end of the horizontal axis n «, which gives motion to the whole machine. This same axis has a pinion, p, upon n. Which gives motion to the wheel r, fixed near the middle of a horizontal axle, wnicn, at its left hand end, has a bevel pinion, f, working the wheel u, before mentioned, uy these means, the rotation of the central axis b will be very slow compared with the motion of the axled; for the latter will make seventeen or eighteen revolutions on its own a*'s m the SMie space of time that it will be carried once round the tun by the motion of the shaft 6. At the beginning of the operation of mashing, the machine is made to turn with a slow motion; but, after having wetted aU the malt by one revo- muon. It is driven quicker. For this purpose, the ascending shaft / g, which gives I 150 BEER. motion to the machine, has two level wheels, h t, fixed upon a tube, /g, which is, fitted upon a central shaft. These wheels actuate the wheels m and o, upon the end of the horizontal shaft n n ; but the distance between ihe two wheels h and i is such, that they cannot be engaged both at once with the wheels m and o ; but the tube / g, to which they are fixed, is capable of sliding up and down on its central axis sufficiently to bring either wheel h or » into gear with its corresponding wheel o or m, upon the horizontal shaft ; and as the diameters of n o, and i rriy are of very different proportions, the velocity of the motion of the machine can be varied at pleasure, by using one or other, k and k are two levers, which are forked at their extremities, and embrace collars at the ends of the \\xbcfg. These levers being united by a rod, I, the handle k gives the means of moving the tube/g, and its wheels h t, up or down, to throw either the one or the other wheel into gear. The object of boiling the wort is not merely evaporation and concentration, but extrac- tion, coagulation, and, finally, combination with the hops ; purposes which are better ac- complished in a deep confined copper, by a moderate heat, than in an open shallow pan with a quick fire. The copper, being incased above in brickwork, retains its digesting temperature much longer than the pan could do. The waste steam of the close kettle, moreover, can be economically employed in communicating heat to water or weak worts ; whereas the exhalations from an open pan would prove a nuisance, and would need to be carried off by a hood. The boiling has a four-fold effect : 1. it concentrates the wort; 2. during the earlier stages of heating, it converts the starch into sugar, dextrine, and gum, by means of the diastase ; 3. it extracts the substance of the hops diffused through the wort ; 4. it coagulates the albuminous matter present in the grain, or precipitates it by means of the tannin of the hops. The degree of evaporation is regulated by the nature of the wort, and the quality of the beer. Strong ale and stout for keeping, require more boiling than ordinary porter or table-beer brewed for immediate use. The proportion of the water carried off by evaporation is usually from a seventh to a sixth of the volume. The hops are introduced during the progress of the ebullition. They serve to give the beer not only a bitter aromatic taste, but also a keeping quality, or they counteract its natural tendency to become sour ; an effect partly due to the precipitation of the albumen and starch, by their resinous and tanning constituents, and partly to the antifermentable properties of their lupuline, bitter principle, ethereous oil, and resin. In these respects, there is none of the bitter plants which can be substituted for hops with advantage. For strong beer, powerful fresh hops should be selected ; for weaker beer, an older and weaker article will suffice. The hops are either boiled with the whole body of the wort, or extracted with a portion of it ; and this concentrated extract added to the rest. The stronger the hops aie, the longer time they require for extraction of their virtues; for strong hops, an hour and a half or two hours boiling may be proper ; for a weaker sort, half an hour or an hour may be sufficient ; but it is never advisable to push this process too far, lest a dis- agreeable bitterness, without aroma, be imparted to the beer. In our breweries, it is the practice to boil the hops with a part of the wort, and to filter the decoction through a drainer, called the jack hop-back. The proportion of hops to malt is very various ; but, in general, from a pound and a quarter to a pound and a half of the former are taken for 100 lbs. of the latter in making good table-beer. For porter and strong ale, 2 pounds of hops are used, or even more ; for instance, one pound of hops to a bushel of malt, if the beer be destined for the consumption of India. During the boiling of the two ingredients, much coagulated albuminous matter, in various states of combination, makes its appearance in the liquid, constituting what is called the breaking or curdling of the worty when numerous minute flocks are seen floating in it. The resinous, bitter, and oily-ethereous principles of the hops combine with the sugar and gum, or dextrine of the wort ; but for this effect they require time and heat ; showing that the boil is not a process of mere evaporation, but one of chemical reaction. A yellowish-green pellicle of hop-oil and resin appears upon the surface of the boiling wort, in a somewhat frothy form : when this disappears, the boiling is presumed to be completed, and the beer is strained off into the cooler. The residuarj' hops may be pressed and used for an inferior quality of beei ; or they may be boiled with fresh wort, and be added to the next brewing charge. Figs. 117,118, represent the copper of a London brewery. Fig. 117 is a vertical section; fig. 118, a ground-plan of the fire-grate and flue, upon a smaller scale : a is the close cop- per kettle, having its bottom convex within ; b is the open pan placed upon its top. From the upper part of the copper, a wide tube, c, ascends, to carry off the steam generated during the ebullition of the wort, which is conducted through four downwards-slanting tubes, d d (two only are visible in this section), into the liquor of the pan 6, in order to warm its contents. A vertical iron shaft or spindle, e, passes down through the tube c. nearly to the bottom of the copper, and is there mounted with an iron arm, called a BEER. 151 rouser, which carries round a chain hung in loops, to prevent the hops from adhering to the bottom of the boiler. Three bent stays,/, are stretched across the interior, to support the shaft by a collet at their middle junction. The shaft carries at its upper end a bevel '''*^'> Sy working into a bevel pinion upon the axis A, which may be turned either by power or by hand. The rouser shaft may be lifted by means of the chain t, which, going over two pulleys, has its end passed round the wheel and axle k, and is turned by a winch : I is B. tube for conveying the waste steam into the chimney m. The heat is applied as follows : — For heating the colossal coppers of the London breweries, two separate fires are required, which are separated by a narrow wall of brickwork, n,Jigs. 117, 118. The dotted circle a' a' indicates the largest circumference of the copper, and 6' b' its bottom ; o o are the grates upon which the coals are thrown, not throtigh folding doors (as of old), but through a short slanting iron hopper, shown at Pyjig. 117, built in the wall, and kept constantly filled with the fuel, in order to exclude the air. Thus the lower stratum of coals gets ignited before it reaches the grate. Above the hopper p, a narrow channel is provided for the admission of atmospherical air, ia such quantity merely as may be requisite to complete the combustion of the smoke of the coals. Behind each grate there is a fire-bridge, r, which reflects the flame upwards, and causes it to play upon the bottom of the copper. The burnt air then passes round the copper in a semicircular flue, s s, from which it flows off into the chimney »w, on whose under end a slidine damper-plate, /, is placed for tempering the draught. When wld air is admitted at this orifice, the combustion of the fuel is immediately checked. There is, besides, another slide-plate at the entrance of the slanting flue into the vertical chimney, for regulating the play of the flame under and around the copper. If the plate the opened, and the other plate shut, the power of the fire is suspended, as it ought to be, at the time of emptying the copper. Immediately over the grate is a brick arch, w, to protect the front edge of the copper from the first impulsion of the flame. The chim- **? i^ ^"PPOJ'ted upon iron pillars, r, r ; ly is a cavity closed with a slide-plate, through which the ashes may be taken out from behind, by means of a long iron hook. Fig. 119 represents one of the sluice-cocks, which are used to make the commu- nications of the pipes with the pumps, or other parts of the brewery, b b represenU the pipe m which the cock is placed. The two parts of this pipe are screwed to the side of a box, c c, in which a slider, a, rises and faUs, and intercepts, at pleasure, the passage of the pipe. The slider is moved by the rod a. This passes through a stuffing- it f t. '' li 152 BEER. box, in the top of the box which contains the slider, and has the rack b fastened to it The rack is moved by a pinion fixed upon the axis of a handle e, and the rack and pinion are contained in a frame d which is supported by two pillars. The frame contains a small roller behind the rack, which bears it up towards the pinion, and keeps its teeth up to the teeth of the pinion. The slider a is made to fit accurately against the internal surface of the box c, and to bear against this surface by the pressure of a spring, so as to make a perfectly close fitting. Fig. 120 is a small cock to be placed in the side of the great store vats, for the purpose of drawing off a small quantity of beer to taste and try its quality, a is a part of the stave or thickness of tne great store vat; into this the tube b of the cock js fitted, and is held tight in its place by a nut, a, a, screwed on withinside. At the other end of the tube b, a plug, c, is fitted, by grinding it into a cone, and it is kept m by a screw. This plug has a hole up the centre of it, and from this a hole pro- .•eeds side-wise, and corresponds with a hole made through the side of the tube when the cock is open; but when the plug c is turned round, the hole will not coincide and then the cock will be shut, d is the handle or key of the cock, by which its plug is turned to open or shut it : this handle is put up the bore of the tube (the cover k being first unscrewed and removed), and the end of it is adapted to fit the end of the plug of the cock. The handle has a tube or passage bored up it, to convey the beer away from the cock when it is opened, and from this the passage/, through the han- dle, leads, to draw the beer into a glass or tumbler. The hole in the side of the plug IS so arranged, that, when the handle is turned into a perpendicular direction with the passage/ downwards, the cock will be open. The intention of this contrivance is that there shall be no considerable projection beyond the surface of the tun; because It sometimes happens that a great hoop of tlie tun breaks, and, falling down, its great weight would strike out any cock which had a projection ; and, if this happened in the night, much beer might be lost before it was discovered. The cock above de- scribed, being almost wholly withinside, and having scarcely any projection beyond the outside surface of the tun, is secure from this accident Fig. 121 is a small contrivance of a vent peg, to be screwed into the head of a common cask when the beer is to be drawn off from it, and it is necessary to admit some air to ^ 121 allow the beer to flow, a a represents a portion of the head of the cask into which the tube b is screwed. The top of C this tube is surrounded by a small cup, from which project the two small handles c c, by which the peg is turned round to screw it into the cask. The cup round the other part of the tube is filled with water ; into this a small cup, d, is in- verted; in consequence, the air can gain admission into the ^^^ V 1-1-1 ^*^^ -when the pressure within is so far diminished, that the air will bubbk up through the watei-, and enter beneath the small cup d. The most efficient substance for fining beer hitherto discovered is isinglass, which is prepared by solution in vinegar or old stale beer, and this solution is afterwards reduced with thm mild beer generally brewed for the purpose, in all large establishments, from a raw or return wort It must next be passed through a fine hair sieve, by means ol rubbing it down with a hard hair-brush, and brought to the proper consistency by tliin mild beer. If properly made, it will be clear, transparent and free from feculencies. Finings serve excellently to remove any extraneous matter that may be found floating in the beer, and thus changes it from bright to brilliant" The common quantity used is from a pint to a quart per barrel, according to the nature of the beer. To ascertain whether the beer is in a fit state for fining, put it into a long glaaj cylindric vessel, and add to it a teaspoonful, or thereby, of the fining ; then give the mixture a good shake, by turning the vessel up and down, after closing its mouth with \ BEER. 158 the palm of the hand. If the beer has been well brewed, its aptitude to become bright will be soon shown by the mixture getting thick and curdy ; a bright portion will gener- ally show itself at the bottom or middle ; after which the finings will gradually mount to the top, takina: up all the impurities along with them, till the whole becomes brilliant Some have said that the finings should carry the impurities down to the bottom ; but this, according to Mr. Black,* takes place only with stubborn beer, which would not be- come thoroughly bright with any quantity of finings which could be introduced. Finings have usually a specific gravity of from I'OIO to 1-016, and, when added to beer in a fit condition for fining, invariably go to the top, and not to the bottom. In fining beer in a barrel laid on its side, if the finings do not make their appearance at the bung-hole, the beer will not become bright. The isinglass must not be dissolved with heat, nor in hot water. Beer brewed from imperfectly malted grain, or from a mixture of malt and raw com, gives a fermentation quite different in flavor from that of beer from sound malt. The nose is, in fact, the best guide to the experienced brewer for ascertaining whether his process is going on well or ill. Ropiness is a morbid state of beer, which is best remedied, according to Mr. Black, by putting the beer into a vat with a false bottom, and adding, per barrel, 4 or 5 pounds of hops, taken gradually away after the first boilings of the worts ; and to them may be added about half a pound per barrel of mustard-seed. Rouse the beer as the hops are gradually introduced, and, in some months, the ropiness will be perfectly cured. The beer should be drawn off from below the false bottom. For theoretical views, see Fermentation ; and for wort-cooling apparatus, see Refbi- gerator. The quantity of beer and ale exported from the United Kingdom amoimted in 1850 to 182,480 barrels, and in 1851 to 191,639; the declared value being respectively 558,794/., and 577,874/. Beer (Bavarian). The Germans from time immemorial have been habitually beer drinkers, and have exercised much of their technical and scientific skill in the produc- tion of beer of many different kinds, some of which are little known to our nation, while one at least, called Bavarian, possesses excellent qualities, entitling it to the at- tention of all brewers and consumers of this beverage. The peculiarities in the manu- facture of Bavai-ian beer have recently attracted the attention of the most eminent chemists in Germany, especially of Professor Liebig, and much new light has thereby been thrown upon this curious portion of vegetable chemistry, which I shall endeav- or to reflect upon the present article. The following is a list of the principal beers at present brewed in Germany. I. Brown beer of Merseburg ; of pure barley malt. — — barley malt and beet-root sugar. — barley malt, potatoes, and beet- root syrup. — refined beet-root syrup alone. Co vent or thin beer. Berlin white beer, or the Champagne of the north. 7. Bro3'han, a famous Hanoverian beer. 8. Double beer of Grunthal. 9. Bavarian beer ; 1. Summer beer; 2. "Winter beer. 10. — Bock-beer. II. Wheat Xa^'^r-beer (slowly fermented). 12. White bitter beer of Erlangen. Considerable interest among men of science, in favor of the Bavarian beer proijess, has been excited ever since the appearance of Liebig's Organic Chemistry, first pub^ lished about twelve years ago. In the introduction to this admirable work, he says, "The beers of England and France, and the most parts of those of Germany, become gradually sour by contact of air. This defect does not belong to the beers of Bavaria, which may be preserved at pleasure in half-full casks, as well as full ones, without al- teration in the air. This precious quality must be ascribed to a peculiar process emploj'ed for fermenting the wort, called in German untcrgahrung, or fermentation from below ; which has solved one of the finest theoretical problems. •' Wort is proportionally richer in soluble gluten than in sugar, f When it is set to ferment by the ordinary process, it evolves a large quantity of yeast in tbe state of a thick froth, with bubbles of carbonic acid gas attached to it, whereby it is floated to the surface of the liquid. This phenomenon is easily explained. In the body of the wort along side of particles of sugar decomposing, there are particles of gluten being oxidized * Treatise on Brewing, 8vo. p. 68. t It does not surely contain more gluten than it does sugar: at least no experiments, known to mo. prove this proposition. ^ 2. 3. 4. 5. 6. H ji t 'i 154 BEER. BAVARIAN. at the same time, and enveloping as it were the former particles, whence the carbonic acid of the sugar and the insoluble ferment from the gluten being simultaneoush pro- duced, should mutually adhere. When the metamorphosis of the sugar is completed there remains still a large quantity of gluten dissolved in the fermented liquor, which gluten, in virtue of its tendency to appropriate oxygen, and to get decomposed, 'induces also the transformation of the alcohol into acetic acid (vinegar). But were all the matters susceptible of oxidizement as well as this vinegar ferment removed, the beer would thereby lose its faculty of becoming sour. These conditions are duly fulfilled in the process followed in Bavaria. " In that country the malt-wort is set to ferment in open backs, with an extensive sur- face, and placed in cool cellars, having an atmospheric temperature not exceedinp 8° or lOP centigrade (46|° or 50° F.). The operation lasts from 3 to 4 weeks; the carbonic acid is disengaged, not in large bubbles that burst on the surface of the liquid, but in very small vesicles, like those of a mineral water, or of a liquor saturated with carbonic acid, when the pressure is removed. The surface of the fermenting wort is always in contact with the oxygen of the atmosphere, as it is hardly covered with froth, and as all the yeast is deposited at the bottom of the back under the form of a very viscid sediment, called in German unterhefe. ** In order to form an exact idea of the difference between the two processes of fer- mentation. It must be borne in mind that the metamorphosis of gluten and of azotized bodies m general is accomplished successively in two principal periods, and that it is in the first that the gluten is transformed in the interior of the liquid into an insoluble ftrment, and that it separates alongside of the carbonic acid proceeding from the sugar. This separation is the consequence of an absorption of oxygen. It is, however, hardly possible to decide if this oxygen comes from the sugar, from the water, or even from an intestine change of the gluten itself, or, in other words, whether the oxygen com- bines directly with the gluten,to give it a higher degree of oxidation, or whether it lays hold of its hydrogen to form water. "This oxidation of the gluten, from whichever cause, and the transformation of the sugar into carbonic acid and alcohol, are two actions so correlated, that by an exclusion of the one, the other is immediately stopped." The superficial ferment {oberhefe in German) which covers the surface of the fer- menting works is gluten oxidized in a state of putrefaction ; and the ferment of d«)o«7« IS the gluten oxidized in a state of eremacausie. The surface yeast, or barm, excites in liquids containing sugar and gluten the same alteration which itself is undergoing, whereby the sugar and the gluten suffer a rapid and tumultuous metamorphosis. We may form an exact idea of the different states of these two kinds of yeast by comparing the superficial to vegetable matters putrefying at the bottom of a marsh, and the bottom yeast to the rotting of wood in a state of eremacausie, that is, of slow combustion. The peculiar condition of the elements of the sediment ferment causes them to act upon the elements of the sugar in an extremely slow manner, and excites the change into alcohol and carbonic acid, without that of the dissolved gluten. Sugar, which at ordinary temperatures has no tendency to combine with oxygen, enters in the above predicament into fermentation ; but the action is rendered much slower by the low temperature, while the affinity of the dissolved gluten for the oxygen of the air is aided by the contact of the sediment. The superficial yeast may be removed without stopping the fermentation, but the under yeast can not be removed without arresting all the phenomena of disoxidation of the second period. These would immediately cease ; and if the temperature were now raised, they would be succeeded by the phenomena of the first period. The deposite does not excite the phenomena of tumultuous fermentation, for which reason it is totally unfit for panification (bread- baking), while the superficial yeast alone is suitable to this purpose. If to wort at a temperature of from 46^° to 50° F. the top yeast be added, a quiet slow fermentation is produced, but one accompanied with a rising: up of the mass, while yeast collects both at the surface and bottom of the backs. If this deposite be removed to make use of it in other operations, it requires by little and little the characters of the unterhe/e, and becomes incapable of exciting the phenomena of the first fermenting period, causing only, of 59° F., those of the second; namely, sedimentary fermentation. It must be carefully observed that the right unterhefe is not the precipitate which falls to the bottom of backs in the ordinary fermentation of beer, but is a matter entirely different. Peculiar pains must be taken to get it genuine, and in a proper condition at the commencement. Hence the brewers of Hessia and Prussia, who wished to make Bavarian beer, found it more to their interest to send for the article to Wurtzburg, or Bamberg, in Bavaria, than to prepare it themselves. When once the due primary fer- mentation has been established and well regulated in a brewery, abundance of the true unterhefe may be obtained for all future operations. BEER, BAVARIAN. 155 In a wort made to ferment at a low temperature with deposite only, the presence of the unterhefe is the first condition essential to the metamorphosis of the saccharum, but it is not competent to bring about the oxidation of the gluten dissolved in the wort, and its transformation into an insoluble state. This change must be accomplished at the cost of the atmospherical oxygen. , . ^ /• r*u In the tendency of soluble gluten to absorb oxygen, and in the free access of the air, all the conditions necessary for its eremacausis, or slow combustion, are to be found It is known that the presence of oxygen and soluble gluten are also the conditions of acetification (vinegar-making), but ihey are not the only ones ; for this process requires a temperature of a certain elevation for the alcohol to experience this slow combustion. Hence, by excluding that temperature, the combustion (oxidation) of alcohol is ob- structed, while the gluten alone combines with the oxygen of the air. This property- does not belong to alcohol at a low temperature, so that during the oxidation in this case of the gluten, the alcohol exists alongside of it, in the same condition as the gluten alongside of sulphurous acid in the muted wines. In wines not impregnated with the fumes of burning sulphur, the oxygen which would have combined at the same time with the gluten and the alcohol does not seize either of them in wines which have been subjected to mutism, but it unites itself to the sulphurous acid to convert it into the sulphuric. The action called sedimentary fermentation is therefore merely a simulta- neous metamorphosis of putrefaction and slow combustion ; the sugar and the unterhefe putrefy, and the soluble gluten gets oxidized, not at the expense of the oxygen of the water and the sugar, but of the oxygen of the air, and the gluten then falls in the in- soluble state. The process of Appert for the preservation of provisions is founded upon the same principle as the Bavarian process of fermentation i in which all the pu- trescible matters are separated by the intervention of the air at a temperature too low for the alcohol to become oxidized. By removing them in this way, the tendency of the beer to grow sour, or to suffer a further change, is prevented. Appert's method consists in placing in presence of vegetables or meat which we wish to preserve the oxygen at a high temperature, so as to produce slow combustion, but without putre- faction or even fermentation. By removing the residuary oxygen after the combustion is finished, all the causes of an ulterior change are removed. In the sedimentary fer- mentation of beer, we remove the matter which experiences the combustion ; whereas, on the contrary, in the method of Appert, we remove that which produces it. It is uncertain whether the dissolved gluten, in being converted into insoluble yeast by the action of the oxygen, combines directly with the oxygen ; that is to say, whether the yeast differs from the soluble gluten merely by having absorbed an additional quan- tity of oxygen. This question is in fact very difficult to solve by analysis. If the gluten be regarded as a hydrogenated combination, it is obvious that in the fermentation of wine-must, and malt-wort, the hydrogen will be carried off by the oxygen, and the action will then be the same as the transformation of alcohol into aldehyde. When the contact of the atmosphere is excluded, this oxygen can not evidently be derived from the elements of the air, or from those of the water ; for it can not be supposed that oxygen will take hydrogen from the water, in order to recompose water with the hydrogen of the gluten. The elements of the saccharum must therefore furnish this oxygen ; or in the course of the formation of the yeast, a portion of the sugar will be decomposed ; but thts decomposition is not of the same kind as that which results from the immediate metamorphosis of the sugar into carbonic acid and alcohol ; hence a certain portion of the sugar will afford neither alcohol nor carbonic acid, but it will yield less oxgenated products from its elements. These products occasion the great difference in the qual- ities of fermented liquors, and particularly in their alcoholic strength. In the ordinary fermentation of grape-juice and worts, these liquids do not furnish a quantity of alcohol equivalent to the sugar which they contain, because a certain portion of the sugar serves for the oxidation of the gluten, and is not transformed like the rest. But whenever the liquor has arrived at the second period, the product in alcohol ought to be equivalent to the quantity of sugar present, as happens in all fermentations which are not accom- panied with a formation, but a disappearance of the yeast. It is well ascertained that worts furnish in the Bavarian breweries 10 or 20 per cent, more alcohol than they do by the ordinary process of fermentation. It is also a well-established fact that in the manufacture of spirits from potatoes, where no yeast is produced, or merely a quantity corresponding to the proportion of barley-malt added to the potato- wort, a quantity of alcohol may be produced, as also of carbonic acid, corresponding exactly to the quan. tity of carbon in the fecula employed. But, on the contrary, in the fermentation of beet-root juice, it is hardly possible to determine precisely, from the quantity of car- bonic acid evolved, the quantity of sugar contained in the beets, for there is always less carbonic acid than the juice of the fresh root would furnish. In equal volumes, the beer made by the unterhefe process contains more alcohol, and is therefore more heady than that formed by the ordinary process. 156 BEER, BAVARIAN BEER, BAVARIAN. 157 !i fl K- fi K i The temp(^rature at which fermentation is carried on has a very marked influence upon the quantity of alcohol produced. It is known that the juice of beets set to ferment between 86° and 95 Fahr. does not yield alcohol, and its sugar is replaced by a less oxygenated substance, mannite, and lactic acid, resulting from the mucilage. In proportion as the temperature is lowered the mannite fermentation diminishes. As to azotized juices, however, it is hardly possible to define the conditions undef which the transformation of the sugar will take place, without being accompanied with another decomposition which modifies its products. The fermentation of beer by deposite demonstrates that by the simultaneous action of the oxygen of the air and a low temperature, the metamorphosis of sugar is effected in a complete manner ; for the vessels in which the operation is carried on are so disposed that the oxygen of the air may act upon a surface great enough to transform all the gluten into insoluble yeast, and thus to present to the sugar a matter constantly undergoing decomposition. The oxidizement of the dissolved gluten goes on, but that of the alcohol requires a higher temperature ; whence it can not sufl'er eremacausis, that is, acetification, or conversion into vinegar. At the beginning of the fermentation of must and wort, the quantity of matter undergoing change is obviously the largest. All the phenomena which accompany it, the disengagement of gas and the rise of temperature, are most active at this period, and in proportion as the decomposition advances, the external signs of it become less perceptible, without, however, disappearing completely before the transformation has reached its limit. The slow and continuous decomposition which succeeds to the rapid and violent disengagement of gases is denominated the after or complementary fermentation. For wine and beer it lasts till all the sugar has disappeared, so that the specific gravity of the liquors progressively diminishes during several months. This slow fermentation is in most cases a truly depositary fermentation ; for by the pro- gressive decomposition of the less, the sugar still in solution gets completely trans* formed ; but when the air is excluded, that decomposition does not occasion the com- plete separation of the azotized matters in an insoluble shape. In several states of the German confederation, the favorable influence of a rational process of fermentation upon the quality of the beers has been fully recognised. In the Grand Dutchy of Hesse considerable premiums were proposed for the brewing of beer according to the process pursued in Bavaria, which were decreed to those brewers who were able to prove that their* product (neither strong nor highly hopped) had kept six months in the casks without becoming at all sour. When the first trials were being made several thousand barrels were spoiled, till eventually experience led to the dis- covery of the true practical conditions which theory had foreseen and prescribed. Neither the richness in alcohol, nor in hops, nor both combined, can hinder ordinary beer from getting tart. In England, says Liebig, an immense capital is sacrificed to preserve the better sorts of ale and porter from souring, by leaving them for several years in enormous tuns quite full, and very well closed, while their tops are covered with sand. This treatment is identical with that applied to wines to make them deposite the wine-stone. A slight transpiration of air goes on in this case through the pores of the wood ; but the quantity of azotized matter contained in the beer is so great, relatively to the proportion of oxygen admitted, that this element can not act upon the alcohol. And yet the beer thus managed will not keep sweet more than two months in smaller casks to which air has access. The grand secret of the Munich brewers is to conduct the fermentation of the wort at too low a temperature to permit of the acetification of the alcohol, and to cause all the azotized matters to be com- pletely separated by the intervention of the oxygen of the air, and not by the sacrifice of the sugar. It is only in March and October that the good store beer is begun to be made in Bavaria. In our ordinary breweries, the copious disengagement of carbonic acid from the frothy top of the fermenting tuns and gjies prevents the contact of oxygen from the worts ; so that, as the gluten can not be oxidized by the air, it attracts oxygen from the sugar, and thus gives rise to several adventitious hydrogenated products, just as the fetid oil is generated in the rapid fermentation of spirit-wash by the distillers. In this case no inconsiderable portion of the gluten remains undecomposed in the beer, which, by its extreme proneness to corruption, afterward attracts oxygen greedily from the air, and, at temperature above 52^, imparts this contact action to the alcohol, and, by a species of infection, changes it into vinegar. Indeed, in most of the rapid fermenta- tions a portion of vinegar is formed, which itself serves as an acetous ferment to the rest of the alcohol ; whereas the result of the bottom fermentation is a beer free from vinegar, and certainly hardly a trace of gluten ; so that it does not possess the conditions requisite to intestine change or deterioration. This perfection is, however, in my opinion, rarely attained. In my several journeys into Germany I have met with much spurious or ill-made Bavarian beer. The best contains, when brought to England, a little acid. but no perceptible gluten on the addition of ammonia in excess, ales, &c., deposits more or less gluten when thus treated. Most of our beers. The following table exhibits the results of the chemical examinations of the under- mentioned kinds of beer : — Name of the Beer. Augustine double beer — Munich Sal vator beer — do. - Bock-beer, from the Royal brewery — do. Schenk (pot) beer, from a Ba- varian country brewery ; a kind of small beer Bock-beer of Brunswick, of the Bavarian kind Lager (store) beer, of Bruns- wick, of the Bavarian kind Brunswick sweet small beer Brunswick mum i Quantity in 100 parts by weight Water. Malt extr. Alcohol. Carb. acid. Analyst. : 88-86 8-0 3-6 0-14 Kaiser. 87-62 8-0 4-2 0-18 Do. 88-64 7-2 4-0 0-16 Do. 92-94 4-0 2-9 0-16 Do. 88-50 6.50 5-0 - Balhorn. 91-0 5-4 3-50 w V Otto. 84-70 59-2 14-0 39-0 1-30 1.80 0-1 Do. Kaiser. Malting in Munich. — The barley is steeped till the acrospire, embryo, or seed-germ, seems to be quickened ; a circumstance denoted by a swelling at the end of that ear which was attached to the foot-stalk, as also when, on pressing a pile between two fingers against the thumb-nail, a slight projection of the embryo is perceptible. As long, however, as the seed-germ sticks too firm to the husk, it has not been steeped enough for exposure on the underground malt-floor. Nor can deficient steeping be safely made up for afterward by sprinkling the malt-couch with a watering-can, which is apt to render the malting irregular. The steep-water should be changed repeatedly, according to the degree of foulness and hardness of the barley ; first, six hours after immersion, having previously stirred the whole mass several times; afterward, in winter, every twenty-four hours, but in summer every twelve hours. It loses none of its substance in this way, whatever vulgar prejudice may think to the contrary. After letting off the last water from the stone cistern, the Bavarians leave the barley to drain in it during four or six hours. It is now taken out, and laid on the couch floor, in a square heap, eight or ten inches high, and it is turned over, morning and evening, with dexterity, so as to throw the middle portion upon the top and bottom of the new-made couch. When the acrospire has become as long as the grain itself, the malt is carried to the withering (welkboden) or drying-floor, in the open air, where it is exposed (in dry weather) during from eight to fourteen days, being daily turned over three times with a winnowing shovel. It is next dried on a well-constructed cylinder or flue- heated malt-kin, at a gentle clear heat, without being browned in the slightest degree, while it turns triable into a fine white meal. Smoked malt is entirely rejected by the best Bavarian brewers. Their malt is dried on a series of wove wire horizontal shelves, placed over each other ; up through whose interstices or perforations streams of air, heated to only 122^ Fahr., rise from the surfaces of rows of hot sheet-iron pipe-flues, arranged a little way below the shelves. Into these pipes the smoke and burned air of a little furnace on the ground are admitted. The whole is enclosed in a vaulted chamber, from whose top a large wooden pipe issues, for conveying away the steam from the drying malt. Each charge of malt may be completely dried on this kiln in the space of from eighteen to twenty-four hours, by a gentle uniform heat, which does not injure the diastase, or discolor the farina.* The malt for store-beer should be kept three months at least before using it, and be freed by rubbmg and siitmg from the acrospires before being sent to the mill, where it should be crushed pretty fine. The barley employed is the liest distichon or common kind, styled hordeum vulgare. The hops are of the best and freshest growth of Bavaria, called the fine spatter, or aaatser Bohemian townhops, and are twice as dear as the best ordinary hops of the rest of Germany. They are in such esteem as to be exported even into France. The Bavarians are so much attached to the beer beverage, which they have enjoyed from their reototest ancestry, that they regard the use of distilled spirits, even in moderation, as so immoral a practice, as to disqualify dram-drinkers for decent society. * I have a set or designs of the Bavarian kiln, but I l)elieve the al>ove description will make its con- stroction sufficiently intelligible. 158 BEER, BAVARIAN. BEER, BAVARIAN. ' - Their government has taken great pains to improve this national beverage, by en- couraging the growth of the best qualities of hops and barley. The vaults in which the beer is fermented, ripened, and kept, are aH underground, and mostly in stony ex- cavations, called felsenkeller or rock-cellars. The beer is divided into two sorts, called summer and winter. The latter is light, and, being intended for immediate retail in tankards, is termed schankbier. The other, or the lagerbier, very sensibly increases in vinous strength in proportion as it decreases in sweetness, by the judicious manage- ment of the nachgdhrung, or fermentation in the casks. In several parts of Germany a keeping quality is communicated to beers by burning sulphur in the casks before fillin^ them, or by the introduction of sulphite of lime. But the flavor thus im- parted is disliked in Munich, Bayreuth, Regensburg, Niimberg, Hof, and the other chief towns of Bavaria ; instead of which a preservative virtue is sought for in an aromatic mineral or Tyrol pitch, with which the insides of the casks are carefully coated, and in which the ripe beer is kept and exported. In December and January, after the casks are charged with the summer or store-beer, the double doors of the cellars are closed, and lumps of ice are piled up against them, to prevent all access of warm air. The cellar is not opened till next August, in order to take out the beer for consump- tion. In these circumstances the beer becomes transparent like champagne wine ; and, since but little carbonic acid gas has been disengaged, little or none of the addi- tionally generated alcohol is lost by evaporation. The winter or schank (pot) beer is brewed in the months of October, November, March, and April; but the summer or store-beer in December, January, and Feb- ruary, or the period of the coldest weather. For the former beer, the hopped worts are cooled down only to from 51° to 55°, but for the latter to from 41° to 42|° Fahr. The winter beer is also a little weaker than the summer beer, being intended to be sooner consumed ; since four bushels* (Berlin measure) of fine, dry, sifted malt, of large heavy hordeum vulgare distichon, affords seven eimers of winter beer, but not more than from five and a half to six of summer beer.f At the second infusion of the worts, small beer is obtained to the amount of twenty quarts from the above quantity of malt. For the above quantity of winter beer, six pounds of middling hops are reckoned sufficient ; but for the summer beer, from seven to eight pounds of the finest hops. The winter beer may be sent out to the publicans in barrels five days after the fer- mentation has been completed in the tuns, and, though not quite clear, it will become so in the course of six days ; yet they generally do not serve it out in pots for two or three weeks. But the summer beer must be perfectly bright and still before it is racked off into casks for sale. Statement of the Products of a Brewing of Bavarian Beer. — The quantity brewed is 41 Munich eimers (64 maass) =85| Berlin quarts; and 60 Berlin quarts = 1 eimer; or 24 Munich barrels (of 100 Berlin quarts each) ; 1 Munich eimer =15 gallons imperial. The beer contains from 50 to 60 parts by weight, of dry saccharum in 1,000 parts. Expenditure, Thaler. Slbg, 24 Berlin bushels of white kiln-dried barley, rather finely crushed, weighing from 12 to 13 cwts. _ _ . - 36 pounds of new fine spatter (parted) hops at 46 thalers the cwt. I pound of Carageen moss, for clarifying - - - 1 quart of yeast. 1 quart of Tyrol pitch ------ Mash — tax (in Bavaria and Prussia) upon 12 cwts. malt, at the rate of 20 siWergroschen = 2s., the cwt. - - - Cost of crushing .-----. Fuel -------- Wages of labor, in the brewhouse and vault . - - Do. Do. for cooper in pitching the casks Sundry small expenses .----- 159 24 16 17 3 11 8 1 4 6 3 2 10 Or IIZ. Ss. 1 thaler = 30 silbergroschen = 3 shillings Deduct for the grains of 12 cwts. of malt, at 10 silbergroschen, or Is. per cwt. = 4 thalers, and for the value in yeast produced = 2 thalers more ------- Total neat expenditure = lOZ. 10*. - - . - 76 - 70 • An English quarter of grain is equal to 5 bushels (scheffeJ) and nearly one third Prussian measure. 1 1 EiTr)er Prussian =15 English imperial gallons ; one Munich scAejfe/ is equal to four Berlin fcAejfelf; 1 Lib. Munich = 1-235 Eng. lbs. Avoird. : I Lib. Berlin = 1031 lbs. Avoird. 24 20 3 11 8 1 4 12 27 81 6 75 This cost for 42 eimers (1 eimer = 14£ galls. Imp.) = 619| gallons = 17'2 London porter barrels, amounts to 4^d. per gallon, or 12*. 2d. per barrel. By the above reckoning, a good profit accrues to the brewer, after allowing a liberal sum for the rent of premises, interest of capital, &c. He has less profit from the summer beer. For a brewing of 33 eimers = 505 gallons Imp., containing from 60 to 65 pounds of saccharum in 1,000 pounds of the beer, by Hermstaedt's saccharometer. Expenditure. Thaler. Slbg. 24 Berlin scheffels of white kiln-dried barley-malt, weighing from 12 to 13 centners* ----.-, 48 Berlin pounds of fresh Bavarian fine hops, at 46 thaler per centner J pound of Carageen moss - - - - . 1 quart setting yeast (unterhefe). 1 centner pitch ------. Malt tax on 12 centners ----.. Crushing the malt -----. Fuel - --.-.. Wages, 6 thalers ; coopers' do., 3 thalers ; and sundries, 3 th. 27 sq. Deduct for grains 4 thalers, and yeast 2 thalers Neat cost -------. This cost of IIZ. 5s. for 505 gallons amounts to fully 5|b is in this stfte to be added to the worts. The lobb is known to be ready when it is covered with a white froth from one quarter to one half an inch thick: during which it must be well covered up. The large fermenting-tun must in like manner be kept covered, even in the vault. The colder the worts, the more yeast must be used. For the above quantity, at _ ^ ^ ^ v x- Tiom bT to 59° Fahi., 6 inaas of unterhefe. 53° to 55° 8 — 48° to 50° 10 — 41° to 33° 12 — Some recommend that wort for this kind of fermentation (the untergahrung) should be get with the yeast at from 48° to 57° ; but the general pracUce at Munich is to set the summer irtgcr beer at from 41° to 43° F. , ,j • ♦!, ~,„ ^r Bv following the preceding directions, the wort m the tun should, m the course of from twelve to twenty-four hours, exhibit a white froth round the rim, and even a sbght whiteness in the middle. After another twelve or twenty-four hours, the froth should appear in curls ; and, in a third like period, these curls should be changed into a still higher frothy brownish mass. In from twenty-four to forty-eight hours more, the barm should have fallen down in portions through the beer, so as to allow it to be seen m cer- tain points. In this case it may be turned over into the smaller ripening tuns m the course of other five or six days. But when the worts have been set to ferment at from 41° to 43° Fahr., they require from eight to nine days. The beer is transferred, aHer being freed from the top yeast by a skimmer, by means of the stopcock near the bottom of the large tun. It is either first run into an intermediate vessel, m order that the top and bottom portions may be well mixed, or into each of the lager casks, in a numbered series, like quantities of the top and bottom portions are introduced. In the ripening cellars the temperature can not be too low. The best keeping beer can never be brewed unless the temperature of the worts at settmg, and of course the fermenting- vault, be as low as 50° F. In Bavaria, where this manufacture is carried on under government inspectors, a brewing period is prescribed by law, which is, for the under fermenting la^er beer, from Michaelmas (29th September) to St. George (23d AprJ). From the latter to the former period the ordinary top-barm beer alone is to be made. The ripening-casks must not be quite full, and they are to be closed merely with a loose bung, in order to allow of the working over of the ferment, ^^^^^^^^^^f .^^e /jj- mentation appear too languid, after six or eight days, a little briskly fermenting lager beer may be introduced. The store lager beer-tuns are not to be quite filled, so as to prevent all the yeasty particles from being discharged in the ripening fermentation; but the pot la-er beer-tuns must be made quite full, as this beverage is mtended for speedy sale within a few weeks of its being made. i, „„ j „wv As soon as the summer beer-vaults are charged with their ripening-casks, and with Ice-cold air, they are closed air-tight with triple doors, having small intervals between, so that one may be entered and shut again, before the next is opened. These vaults are sometimes made in ran-es radiating from a centre, and at others m rooms set ofl at right andes to a main gallery ; so that in either case, when the external opening is well secured, with triple air-tight doors, it may be entered at any time, in order to inspect the interior, without the admission of warm air to the beer-barrels. The wooden bungs for loosely stopping them must be coated with the proper pitch, to prevent the possibility of their imparting any acetous ferment. In the Beer Brewer of A. F. Zimmermann, teacher of theoretical and practical brewing, who has devoted thirty.fi ve years to this business, it is stated, that a ripened tun of lager or store-beer must be racked off all at once, for when it is left half full it becomes flat (schaal) ; and that the tun of pot lager beer must, if possible, be all drunk off in the same day it is tapped: because on the following day the beer gets an unpleasant taste, even when the bukg has not been taken out, but only a small hole has been made, which is opened only at the time of drawing the beer, and is immediately closed again with a ♦ Der Bicr.Braucr, als Meister in seinem fache, Ac, iUustrates with many plates, BerUn. 184a. BEER, BAVARIAN. 161 spigot. He ascribes this change to the loss of the carbonic acid gas, with which Uie beer has got strongly impregnated during the latter period of its ripening, while being kept in tightly-bunged casks. The residuums in these casks are, however, bottled up in Bavaria, whereby the beer, after some time, recovers its brisk and pungent taste. But the beer-topers in Bavaria, who are professedly very numerous, indulge so delicate and fastidious a palate, that when assembled m their lavorite pot- house, they wait impatiently for the tapping of a fresh cask, and cease for a whUe to tipple whenever it is half empty, puffing the time away with their pipes till another fresh tap be made. In the well-frequented beer-shops of Munich a common-sized cask oilagzr boer is thus drank ofi'in an hour. A reputation for superior brewing is there the readiest road to fortune. Bock'Beer of Bavaria.— This is a favorite double strong beverage, of the best lager description, which is so named from causing its consumers to prance and tumble about like a buck or a goat; for the German word bock has both these meanings. It ia merely a beer having a specific gravity one third greater, and is therefore made with a third greater proportion of malt, but with the same proportion of hops, and flavored with a few coriander-seeds. It has a somewhat darker color than the general lager beer, occasionally brownish, taste less bitter on account of the predominating malt, and somewhat aromatic. It is an eminently intoxicating beverage. It is brewed in December and January, and takes a long time to ferment and ripen ; but still it con- tains too large a quantity of unchanged saccharum and dextrine for its hops, so that it tastes too luscious for habitual topers, and is drunk only from the beginning of May till the end of July, when the fashion and appetite for it are over for the year. Statement of a Brewing of Bavarian Bock-Beer. For 41 Bavarian eimers of 64 maass each (about 15 gallons Imperial) per eimer, ot 615 gallons, nearly 17 barrels English in all : — Thaler, SWg. 32 20 3 11 11 11 20 16 51 91 7 84 Expenditure, 32 Berlin scheff'els of the best pale malt freed from its acrospires, weighing 17^ centners, at 1 thaler per centner 48 lbs. (Berlin) of the best Bavarian hops ^ lb. Carageen moss for clarifying - - - 1 lb. Coriander-seeds - . . . • I Quart setting yeast. 1 Centner Tyrolese pitch - - - • • Malt-tax — _----. Mfidt-crushing, fuel, wages, coopering, &c. Thalers of 3«. each Deduct for the value of grains and yeast Thalers of neat cost . - . - - This statement makes the eimer of the Bavarian bock-beer amount to about 2 tha- lers, or 6 shillings ; being at the rate of nearly 5 pence per gallon ; though without counting rent, interest of capital, or profit. It is, in fact, a malt or barley sweet wine or liqueur ; but a very cheap one, as we see by this computation. The chief difference in the process for making bock-beer lies in the mash-wort", and in the hops being boiled a shorter time, to preserve more of the aroma, and acquire less of the bitterness of the hop. The coriander-seeds are coarsely bruised, and added along with the hops and Carageen moss, to the boiling mash-worts, about twenty or thirty minutes before they are laded or drawn off into the mash-tun. Sometimes the hops are boiled apart in a little clear wort, as formerly described. The bock-beer is retailed in Munich at 3 silver groschen, about 3|d. the seidel, or pot, which is one English pint. The 25 gallon cask {imne) is sold at 10 thalers, or 30 shillings. The publicans, therefore, have a very remunerating profit per pot, even supposing that they do not reduce the beer with water like our London craftsmen. Zimmermann assumes the merit of having introduced (^arageen moss as a clarifier into the beer manufacture. I do not know whether it may not have been used in this country for the same purpose, or in Ireland, where this fucus (Chondra crispa) grows abundantly. He says that 1 ounce of it is sufficient for 25 gallons of beer ; and that it operates, not only in the act of boiling with the hops, but in that of cooling, as also in the squares and backs before the fermentation is begun. Whenever this change, however, takes place, the commixture throws up the gluten and moss to the surface of the liquid in a black scum, which is to be skimmed off, so that the proper yeast may K > 162 BEER, BAVARIAN. not be soiled with it. It occasions the separation of much of the vegetable slime, or mucilage, called by the German brewers pech (pitch). On the Clarifying or Clearing of JBeer*.— Clarifiers act either chemically— by being soluble in the beer, and by forming an insoluble compound with the vegetable gluten and othei viscid vegetable extracts ; gelatine and albumen, under one shape or other) have been most used ; the former for beer, the latter, as white of egg, for wine or mechanically, by being diffused in fine particles through the turbid liquor, and, in their precipitation, carrying down with them the floating vegetable matters. To this class belong sand, bone-black (in some measure, but not entirely), and other such articles. The latter means are very imperfect, and can take down only such matters as exist already in an insoluble state ; of the former class, milk, blood, glue, calf 's-foot jelly, hartshorn-shavings, and isinglass, have been chiefly recommended. Calve's-foot jelly is much used in many parts of Germany, where veal forms so common a kind of butcher-meat ; but in summer it is apt to acquire a putrid taint, and to impart the same to the beer. In these islands, isinglass swollen and partly dissolved in vinegar, or sour beer, is almost the sole clarifier, called finings, employed. It is costly, when the best article is used ; but an inferior kind of isinglass is imported for the brewers. The solvent or medium through or with which it is administered is eminently inju- dicious, as It never fails to infect the beer with an acetous ferment. In Germany their tart wine has been used hitherto for dissolving the isinglass ; and this has also the same bad property. Mr. Zimmermann professes to have discovered an unexception- able solvent in tartaric acid, one pound of which dissolved in 24 quarts of water is capable of dissolving two pounds of ordinary isinglass; forming finings which may be afterward diluted with pure water at pleasure. Such isinglass imported from Peters- burg into Berlin costs there only 3«. per lb. These finings are best added, as already mentioned, to the worts prior to fermentation, as soon as they are let in to the setting- back or tun, immediately after adding the yeast to it. They are best administered by mixing them in a small tub with thrice their volume of wort, raising the mixture into a froth with a whisk (twig-besom, in German), and then stirring it into the worts. The clarification becomes manifest in the course of a few hours, and when the fermentation is completed, the beer will be as brilliant as can be wished; the test of which with the German topers is when they can read a newspaper while a tall glass beaker of beer is placed between the paper and the candle. One quart of finings of the above strength will be generally found adequate to the clearing of 100 gallons of well-brewed lager- beer, though it will be surer to use double that proportion of finings. The Carageen moss, as finings, is to be cut in fine shreds, thrown into the boilin? thin wort, when the flocks begin to separate, and before adding the hops ; after which the boiling is continued for an hour and a half or two hours, as need be. The clarifying with this kind of finings takes place in the cooler, so that a limpid wort may be drawn off into the fermenting back. Berlin White or Pale Beer (Weias^er).— This is the truly patriotic beverage of Prussia Proper, and he is not deemed a friend to his Vaterland who does not swig it. It is brewed from 1 part of barley-malt and 5 parts of wheat-malt, mingled, moistened, and coarsely crushed between rollers. This mixture is worked up first with water at 95® Fahr., in the proportion of 30 quarts per scheffel of the malt, to which pasty mixture 70 quarts of boiling water are forthwith added, and the whole is mashed in the tun. After it has been left here a little to settle, a portion of the thin liquor is drawn off by the tap, transferred to the copper, and then for each bushel of malt there is added to it a decoction of half a pound of Mlmark hops separately prepared. This hopped wort, after half an hour's boiling, is turned back with the hops into the mash-tun, of which the temperature should now be 162^° Fahr., but not more. In half an hour the wort is to be drawn off from the grains, and pumped into the cooler. The grains are afterward mashed with from 40 to 50 quarts of boiling water per scheffel of malt, and this infusion is drawn off and added to the former worts. The whole mixture is set at 66° Fahr., with a due proportion of top yeast or ordinary barm, and very moderately fermented. According to Zimmermann, a very competent judge, this hia native beer is very apt to turn sour, and therefore it must be very speedily consumed. This proneness to acetification is the character of all wheat-malt beers. He recom- mends, what he himself has made for many years, a substitution of potato-starch sugar for this sort of malt, and as much tartaric acid as to give the degree of tartness peculiar to the pale Berlin beer, even in its best state. This acid moreover prevents the beer from running into the acetous fermentation. Potato-Beer. — The potatoes being well washed are to be rubbed down to a pulp by such a grating cylinder-machine as is represented inftg. 122, where a is the hopper for receiving the roots (whether potato or beet, as in the French sugar-factories ; h is the crushing and grinding-drum ; c, the handle for turning the spur-wheel d, which drive? the pinion «, and the fly-wheel/; g. A, is the frame. The dotted lines above c, aie the BEER, BAVARIAN. 168 cullender through which the pulp passes. Fig.UZ is the stopcock used in Bavaria fojr tottirng beer. For every scheffel of potatoes 80 quarts of water are to be put with them into the copper, and made to boil. Crushed malt, to the amount of 12 scheffels, is to be well worked about in the mash- tun with 360 quarts, or 90 gallons (English) of cold water, to a thick pap, and then 840 additional quarts, or about 6 barrels (English) of cold water are to be successively introduced with constant stirring, and left to stand an hour at rest. The potatoes having been meanwhile boiled to a fine starch paste, the whole malt- mash, thin and thick, is to be speedily laded into the copper, and the mixture in it is to be well stirred for an hour, taking care to keep the temperature at from 144** to 156° Fahr. all the time, in order that the diastase of the malt may convert the starch present in the two substances into sugar and dextrine. This transformation is made manifest by the white pasty liquid becoming transparent and thin. Whenever this 164 BEER, BAVARIAN. happens the fire is to be raised, to make the mash boil, and to keep it at this heat for 10 minutes, ihe fire is then withdrawn, the contents of the copper are to be transferred into the mash, worked well there, and left to settle for half an hour; during which time the copper is to be washed out, and quickly charged once more with boiling The clear wort is to be drawn off from the top of the tun, as usual, and boiled as soon as possible with the due proportion of hops ; and the boiling water may be added m any desired quantity to the drained mash, for the second mashing. Wort made in this way 18 said to have no flavor whatever of the potato, and to clarify more easily sacc^^A ^^^ contaimng a smaller proportion of gluten relatively to that of A scheffel of good mealy potatoes affords from 26 to 27 J lbs. of thick, well-boiled syrup, of the density of 36° Baum6 (see Areometer); and 26 lbs. of such syrup are equivalent to a scheffel of malt in saccharine strength. Zimmermann thinks beer so brewed from potatoes qmte equal, at least, if not superior, to pure malt beer, both in appearance and quality. * ' r » ^^ofessor Leo, of Munich, has given the following analysis of two kinds of Munich Specific gravity Alcohol - - Extract - - Carbonic acid Water - - - Bock-bier. 1-020 HelllgerVater. 1-030 4-000 8-200 0-085 87-393 100-000 5-000 13-500 0-077 81-923 100-000 tra^t'^e'slg^^ ^^^ *^*'*'^''^ *"" *^'^ Bavarian beer of Bamberg at only 2840 in 100. Ex- The foUowing analyses of other German beers are also by Leo:— Lichtenhain. Upper Weimar. Ilmenatu Jona. Doable Jena. Alcohol Albumen - - - . Extract Water 8168 0-048 4-485 92-299 2-567 0-020 7-316 90-097 3-096 0-079 7-072 89-753 3-018 0-045 6144 90-793 2-080 0-028 7-153 90-739 100-000 100-000 100-000 100-000 100-000 8 -5 in 100 6-2 5*8 60 6-0 4-0 friYr w-^^ *!"^ extract, in these analyses, is meant a mixture of starch, sugar dex- The following statement is from some of the published analyses of other beers — English ale ^^*^^"^ Burton ----.. Scotch ---.._ Common London ale - - - _ Brown stout - - . . . London porter - - - folWs^-^'''' ^ '^^ '^" ^"""'"^"^ *°'^^«'« "^'«^^*^"^^ ^1^« ^«<3« lately by myself as acid iere ZeSedTtl^k It^tn^^T ^" * ^'"? ^^^ *^" *^^ ^"^^^^ ^^ <^^'^^'- ftopplr '^'^^°^*^'''*' ^ ^^ ^^^ «Pe«»fic gravity in a globe with a capillary bored V>i* } *^^° ?^V**f^. ^^^? ^'l^^ measures of the ale with a test solution of pure car- bonate of soda, to determine the ouantitv of ft^Jrl T^^..aor,i. ^4- \.- ur j j^j cess of the alklli to precipitate the^Xten • whTck Kvl ( -' ^^'t ^ 1??'^ ^"^ ^'" I did not separate by a ^Iter, dry, Ind wdgh ^ ^''' ^^'""^ ^""^ '°^" '^ *°'^''^'' 3. I subjected the supersaturated liquid to distillation bv the heat of 9^no F chlor-zmc bath till I drew off all its alcohol of whioh T nnf^i fti^ IF- grain measures and the specific gravity ^ ""^^^^ ^^^ ^^''^^'^^ "^ ^' m a water- I. i ' t BEER (BITTER). 165 4. I evaporated to dryness 500 water-grain measures slowly in a porcelain capsule, t-o determine the extract Specific gravity Alcohol - Extract - Acetic acid Water- - Bavarian. Do. Bock. 1-004 1-013 4 00 4-50 0-20 91-30 4-50 6-40 0-20 88-90 100-00 10000 AIIsop's. 1-010 6-00 5-00 0-20 88-80 100-00 Bass's. 1-006 7-00 4-80 0-18 88-02 100.00 The Bavarian beers had been recently imported from Germany in casks lined with Eitch. The two samples of English ale are those made chiefly for the Indian market, ut, being highly hopped, and comparatively clean, as the brewers say, have been recommended as a tonic beverage by the faculty. Hodgson's bitter beer was the ori- ginal of this quality. The above Bavarian beers afford no precipitate of gluten with carbonate of potash ; the two English ales become mottled thereby, and yield a small portion of gluten, which had been held in solution by the acid, which is here estimated as the acetic. Common vinegar, excise strength, contains 6 per cent, of such acid as is stated in the above analysis, indicating from 3 to 4 per cent, of table vinegar in the above varieties of beer. Ale, pale or bftter ; brewed chiefly for tlie Indian market and for other tropical coun- tries. — It is a light beverage, with much aroma, and, in consequence of the regulations regarding the malt duty, is commonly brewed from a wort of specific gravity 1 055 or upwards ; for no drawback is allowed by the excise on the exportation of beer brewed from worts of a lower gravity than 1 -054. This impolitic interference with the opera- tions of trade compels the manufacturer of bitter beer to employ wort of a much greater density than he otherwise would do ; for beer made from wort of the specific gravity 1 -042 is not only better calculated to resist secondary fermentation and the other effects of a hot climate, but is also more pleasant and salubrious to the consumer. Under pre- sent circumstances the law expects the brewer of bitter beer to obtain 4 barrels of marketable beer from every quarter of malt he uses, which is just barely possible when the best malt of a good barley year is employed. With every quarter of such malt 16 lbs of the best hops are used ; so that, if we assume the cost of malt at 60s. per quarter, and the best hops at 2«. per lb., we shall have, for the prime cost of each barrel of bitter beer, in malt 15»., in hops 8«., and together 23». ; from which, on exportation, we must deduct the drawback of 6s. per barrel allowed by the excise, which brings the prime cost down to 18«. per barrel, exclusive of the expense of manufacture, wear and tear of apparatus, capital invested in barrels, cooperage, f "" "^^ of pearl-powder is prepared by adding a very dilute solution of common salt to the above nitric solution of bismuth, whereby a pulverulent sub-chloride of the metal is obtained m a light flocculent form. A similar powder of a mother-of-pearl aspect may be formed by dropping dilute muriatic acid into the solution of nitrate of bismuth. The arsenic always present in the bismuth of commerce is converted by nitric acid into arsenic acid which, forming an insoluble arseniate of bismuth, separates from the solution, unless there be such an excess of nitric acid as to re-dissolve it. Hence the medicinal oxyde, prepared from a rightly-made nitrate, can contain no arsenic. If we write with a pen dipped in that solution, the dry invisible traces will become legible on plunging the paper m water. ^ It has been proposed to substitute bismuth for lead in assaying silver, as a smaUer quantity of it answers the purpose, and, as its oxyde is more fluent, can therefore penetrate the cupel more readily, and give a more rapid result. But, independently ^ the objection from its high price, bismuth has the disadvantage of boiling up, as wel as of rocking or vegetatmg, with the silver, when the cupeUation requires a hich heat. In extracting the silver from the galena found in the copper-mine of Yahlun. It has happened sometimes that the sUver concreted towards the end of the operation 5nl nfl^f I cauliflower excrescence, which had to be cupelled again with a fresh ?hT .^Ll p r^' ''}T^. *>^^' '" ^^'^ "^'"' ^ P°''ti«« «f the silver had passed into bismuth ^'^"'^^'^' ^^^^^^^^ ^" ^ s^Ple of sUver thus concreted the presence of The nitrate of bismuth, mixed with solution of tin and tartar, has been employed as a mordant for dyeing lilach and violet in calico printing. p ycu as a in fhf^f^; J^^'Jrrw' ' .^^^'^%Ge™-) A brown color which is used in water colors, frrred tL Z f "^ l"^'. ? ^^P^^P^^^ from wood-soot, that of beech being pre! S^v nnlvTi-Lr'i/ P''?^^ ^f ' ^T"'^ P^'^^^^ «^ ««°t "^ <^o"ected from the chim- ney, pulver^ed, and passed through a silk sieve. This powder is infused in pure water, ef If tt lir:lJ T' V ^^T r^''^ *^^" ""«^^ ^« ^^«1^' ^hen the water is deS ThP iLtp if nnw ♦ X^ ^ "^^/-"^ ^"^^^^ '^^ P^«^^^« °^^y be repeated with warm water. y„H [pft tn Mitw e P^".'"^^/"^^ ^ ^«J^g ^^^^ vessel filled with water, stirred weU, and left to sett e for a few minutes, m order to let the grosser parts subside The super natant part is then to be poured ofi" into a similar vessel. This process may be repeated fi^^nH wh'n'r'p"??'" ""r' ^""^ ^'''''- ^' '^^* '^^ settled deposite is suffidenSy fntn nrnnZ . w ^omits Supernatant water, it is mixed with gum-water, moulded mto proper cakes, and diied. It is not used in oil painting, but has the same effect in water-colors as brown pmk has in oil. *- o* ^ a-mc ^ucvi, m I BITTER PRINCIPLE {Ain^re, Fr. ; Bittentoff, Germ.) This principle has not been insulated hitherto by the chemist from the other proximate principles of plants, but its existence is suflSciently recognized by the taste. The following list contains the principal bitter substances, many of which have been used in the arts and in medicine. • Nome. Quassia Wormwood Aloe Angustura Orange Ditto Acorus Carduus Benedictus Cascarilla Centaury Camomile Colocynth Colombo Fumitory Gentiana lutea Ground Ivy Walnut Island moss * Hops Milfoil Large-leaved Satyrion Rhubarb Rue Tansy Bitter trefoil Simarouba Bryony Coffee Part employed. Wood Herb Inspissated juice Bark Unripe Fruit Peel Root Herb Bark Herb Flowers Fruit Root Herb Root Herb Peels Country. Scales of the fe- male flowers Herb flowers Herb Root Herb Herb flowers Herb Bark Root Seeds [ Surinam, E. Indies Great Britain South Africa South America South of Europe ) Ditto J Ditto Greek Archipelago Jamaica Great Britain Levant East Africa Great Britain Switzerland Great Britain Great Britain Great Britain Great Britain China Great Britain Ditto Ditto Guiana Observations. Great Britain Arabia J Powerfully bitter Ditto Ditto Ditto Aromatic bitter Ditto Ditto Intolerably bitter Very bitter Very bitter With tannin With starch Aromatic bitters Disagreable odor Bitter and sharp Bitter and offensive j Sharp, bitter, nau \ seous BITUMEN, or ASPHALTUM. {Bitume, Fr. ; Erdpech, Germ.) A black sub- stance found m the earth, externally not dissimilar to pit-coal. It is composed of carbon, hydrogen, and oxygen, like organic bodies; but its origin is unknown. It has not been observed among the primitive or older strata, but only in the secondary and alluvial formations. It constitutes sometimes considerable beds, as in the Isle of Trinidad, where it occurs over an extensive district, in scattered masses. The greater part of the asphaltum to be met with in commerce comes from the Dead Sea, on whose shores It 18 cast up and gathered ; whence it has got the name of Jewish bitumen. In Its black color and fracture it resembles ordinary pitch. By friction it affords nega- tive electricity. Its average density is MS. It melts at the temperature of boiling water, kindles very readily at the flame, burns brightly with a thick smoke and leaves little ashes. Distilled by itself, it yields a peculiar bituminous oil, very little water, some combustible gases, and traces of ammonia. It leaves about one-tliird of Its weight of charcoal after combustion, and ashes, containing silica, alumina, oxide of iron, sometimes a little lime, and oxide of manganese. According to John, asphaltum may be decomposed, by different solvents, into three distinct substances. Water dis- solves nothing ; alcohol (anhydrous) dissolves out a yellow resin equal to 5 per cent, of the weight of the asphaltum ; that resin is soluble in dilute alcohol and in ether. The portion not soluble in the alcohol gives up a brown resin to ether, amounting to 70 i^er cent of the weight of the asphaltum. On evaporating off the ether, the resin remains ot a brownish-black colour, which dissolves readily in the volatile oils and in the oil ^ i^ti ^- "; r^^ portion of asphaltum which does not dissolve in ether is very soluble m oil of turpentine, and in oil of petroleum; but less so in oil of lavender. Ihese three resinous principles dissolve all together by digestion in the oils of anise, rosemary, turpentine, olive, hemp-seed, nut, and linseed. Caustic potash dissolves a notable quantity of asphaltum ; but carbonate of potash has no effect upon it Asphaltum enters into the composition of hydraulic cements, and into that of black varnishes called japans, for coating iron trays, etc. A similar varnish may be pre- pared by dissolving 12 parts of fused amber, 2 parts of rosin, and 2 parts of asphaltum, m parts of Imseed oil varnish, to which 12 parts of oil of turpentine have been added. 174 BITUMEN. Thei e is a kind of bitumen found at Aniches, in France, in the department of the Korth, which is black, very fusible aud soft It burns with flame. Alcohol, ether, and oil of turpentine extract from it a fatty substance, which may be saponified with alkalis, "^^e bitumen of Murindo, near Choco, in Columbia, is of a brownish-black color, sof^ and has an earthy fracture. It has an acrid taste, burns with a smell of vanilla, and is said to contain a large quantity of benzoic acid. It appears to be the result of the decomposition of trees containing benzoin. Asphaltum occurs abundantly at the surface of the salt lake Asphaltites, in Judea, produced from springs in the neighborhood ; it is floated down, gathers consistence, and accumulates upon the surface of the lake ; the winds drive it on the shores, and the inhabitants collect it for sale. Its inspissation diff'uses a disagreable smell in the air of that region, which is supposed by the natives to be powerful enough to kill birds ■when they attempt to fly across the lake. But probaby the most remarkable locality of asphaltum in the world is the entire basin or rather plain of it, in the island of Trmidad, called the Tar Lake. It lies on the highest land in the island, and emits a strong smell, sensible at ten miles' distance. Its first appearance is that of a lake of water, but when viewed more nearly it seems to be a surface of glass. In hot weather its surface liquifies to the depth of an inch, and it cannot then be walked upon. It is of a circular form, about three miles in circumfe- rence, and of a depth not ascertained. Large fissures frequently open and close up in it, whence the pitch has been supposed to float upon a body of water. The soil for a considerable distance round it, consists of cinders and burnt earth, and presents in many points indications of convulsions by subterranean fire. In several parts of the neighboring woods, there are round holes and fissures in the ground, containing liquid bitumen to the depth of two inches. Mr. Hatchett examined some specimens from Trinidad, and concluded that what had been heretofore supposed to be a pure mineral pitch was in reality only a porous stone of the argillaceous kind, much impregnated with bitumen. These various bitumens belong exclusively to the secondary and tertiary geol(^i- cal formations, and are not found among primitive rocks, except very rarely in veins. They occur most generally in calcareous, argillaceous and ?andy strata, and also in volcanic districts. Petroleum frequently floats on the waters which issue from the volcanic mountains, or which lie at their base ; even the sea is at times covered with it near the volcanic islands of Cape de Verd. Mr. Breislack observed a petroleum spring rising from the bottom of the sea near the south base of Vesuvius. The substance with which bitumen seems to have the most constant and most re- markable relations is sea-salt ; so that almost all the countries most abundant in pe- troleum, as Italy, Transylvania, Persia, the environs of Babylon, the region of the Dead Sea, , ^"" * season, most unpropitious to the laying of bituminous m^tkl R^l^ blK:ks not more than three or four inches tSTanr?fwi;ichcontat!Sl,l seem to have a propensity to decompose by the joint a^eScv of watJr In/^ u ^^^* mineral pitch has been known to remain f^ ageTw t^ouraltfraUoi ' ^^'"^ ^ZZ\t^:ZeTZ^.l:^^^^^^^^^ as the native rock, of which thTrichest and most P.tPn^V '^ ^^' ^^^" P'^'P^'^J' ^^"^'l asphaltic Val^-TraversX the a^nlr^^^ "" unquestionably that of the in the Jurassic limestonr?ormLtYonf thf e^^^ mineral deposite occurs is very accessible, and may be S ly Lclvated ^^^^^^ '^^' P^ "^^^^ stone is massive, of irregular fracture orrilvirhrnLni^ "^'i^- ^.""P^^^er. The a few minute spindes of calcareous spar Though h^"*^?.'* ^"^ "interspersed with it is diflicult to break by the hammer Whin .v?t VT^ ^^ scratched with the nail, hales a fragrant ambrosiirsmeUra pro^^^^^^^ it ex! compounds of factitious bitumpn Tt« crlJ-fi ^ once distinguishes it from all being nearly thrStv of S^ uJ^^"" gravity is 2-114, water being 1,000, it in succesJivrporSof ho o^^^^ most conveniently analyzed bydige ting pulverulent carffirof Hme and 20 ^^^^^^^^^^ 'in/?"'^nS ^^ ?««« of a whiti Val-de-Travers seems ther'Sret iT rfche \^^^^^^ °^ cording to the statement in the snecificatinn nf ri -a , *^ ®^ Pyrimont, which, ac contains "carbonate of lime and SSn ab^L th^^^^^^ patent, of November, 1837, of lime to about 10 parts of Wtumen » Proportion of 90 parts of carbonate ^^Z^^l^ "ifofTrtetrV^' penetrated with the bitumen, muriatic acid; a circumstance partTv dueTftL ♦ f7 ^t""^^^ ^^ ^^^' ^"^ «^^« ^f mineral, but chiefly to the vast Incumhpnt 11 ^""^^^ f '^"'^ *^^ ^«»«^"^e ^^ the have been incorporated in ^he boweS n? tiff ''!f! "^ "/"" ^?^*^^ ^^« ^^^ '"^terials matter to combine, by aA^cial meThid. .,i ^'''^^' V°"^^ '""^^^ ^^ « ^^f^<^^^^ men, and for this reLon thp Lfc!- ^ ' ^^"""^".^ earth thus intimately with bitu- perishable. Many of he factidous t'n^u " '" '^'' ^"^ ^'^ ^^"^^ *« ^'^'^'^ ^ore of siliceous sand, Lm which JhflT ^^.u^ ^^°'^''^' contain a considerable quantiti when trodden upon In fact tLre7eems^^h^^^^^^ ^^""^»>"'^ ^«^^ matter and bitumen, that their nart^ IZ^L r '° ^'^?^ attraction between siliceous tive force. ^^"^^ separate from each other by a very small disrup- Since the asphalt rock of Val-de-Travers is naturally rich enough in concrete bitu- • See the conclusion of thl« article. 176 BITUMEN. men, it, may be converted into a plastic workable mastic of excellent qualitjr for foot pavements and hydraulic works at verv little expense, merely by the addition of a very small quantity of mineral or coal tar, amountmg to not more than 6 or 8 per cent The union between these materials may be eflfected in an iron cauldron, by the application of a very moderate heat^ as the asphalt bitumen readily coalesces with the tar into a tenacious solid. i m The mode adopted for making the beautiful asphalt pavement at the Place de la Concorde in Paris was as follows : — ^The ground was made uniformly smooth, either in a horizontal plane or with a gentle slope to carry off the water; the curb-stones were then laid round the margin by the mason about 4 inches above the level of the ground. This hollow space was filled to a depth of 3 inches with concrete, containing about a sixth part of hydraulic lime, well pressed upon its bed- The surface waa next smoothed with a thin coat of mortar. When the whole mass had become per- fectly dry, the mosaic pattern was set out on the surface, the moulds being formed of flat iron bars, rings, BITUMEN. 177 analysis. The tar of Bastenne is an exceedingly viscid mass, without any earthy im- purity. It has the consistence of bakers' dough at 60° of Fahrenheit ; at 80° it yieldti to the slightest pressure of the finger ; at 150° it resembles a soft extract ; and at 212*^ it has the fluidity of molasses. It ia admirably adapted to give plasticity to the cal- careous asphalts. ** A specimen of Egyptian asphalt which he brought me, gave by analysis the very same composition as the Val de Travers, namely, 80 per cent of pure carbonate of lime, and 20 of bitumen. A specimen to mtistic, prepared in France, was found to consist, in 100 parts, of 29 of bitumen, 52 of carbonate of lime, and 19 of silicious sand. A portion of stone called the natural Bastenne rock afi'orded me 80 parts of gritty silicious matter and 20 of thick tar. The Trinidad bitumen contains a consideraWa portion of foreign earthy matter ; one specimen yielded me 26 per cent of silicious sand ; a second, 28 ; a third, 20 ; and a fourth, 30 : the remainder was pure pitch. One specimen of Egyptian bitumen, specific gravity 1-2, was found to be perfectly pure; for it dissolved in oil of turpentine without leaving any appreciable residuum. Robinson's Parisian Bitumen company use a mastich made with the pitch obtaineil from boiling coal-tar mixed with chalk. One piece laid down.by this company at Knightsbridgc and another at Brighton, are said to T.uve gone to pieces. The portion of pavement laid down by them in Oxford street, next Charles street, has been taken np. Claridge's company have laid down their mastich under the archway of the Horse- Guards, and in the carriage-entrance at the Ordnance Office ; the latter has cracked at the junction with the old pavement of Yorkshire curb-stone. The foot-pavement laid down by Claridge's company at Whitehall has stood well. The Bastenne company has exhibited the best specimen of asphalt pavement in Oxford street ; they have laid down an excellent piece of foot-pavement near Northumberland House ; a piece, 40 feet by 7, on Blackfriars' Bridge ; they have made a substantial job in paving 830 superficial feet in front of the guard-room at Woolwich, which, though much traversed by foot-passengers, and beat by the guard in grounding arms, remains sound ; lastly, the floor of the stalls belonging to the cavalry barracks of the Blues at Knightsbridgc, is probably the best example of asphaltic pavement laid down in this country, as it has received no injury from the beating of the horses' feet. A.S the specific gravity of properly-made mastich is nearly double that of water, a cubic foot of it will weigh from 125 to 130 lbs. ; and a square foot, three quarters of an inch thick, will weigh very nearly eight pounds. A ton of it will therefore cover 280 square feet. The prices at which the Bastenne Bitumen company sell their prod- ucts is as follows : — Pure Mineral tar, 241. per ton, or 28^. per r,wt. Mastich 8/. 8s. per ton, or lOs. per cwt. Side Pavement. From 50 to 100 feet. Is. 3d. per foot. 100 250 1*. Id. 250 500 Ud. 500 750 lOd. 750 1000 9d. 1000 2000 Sd. 2000 5000 Id. *\ Roofs and Terraces. Is. 6d. per foot. 1*. 4d. Is. Id, Is. Od. Ud. lOd. 9d. Where the work exceeds 5,000 feet, contracts may be entered into. For filling up joints of brickwork, &c., from Id. to l^d. per foot, run accordini? tc quantity. ^^ These prices are calculated for half an inch thickness, at which rate a ton wiU cove* 420 square feet. T ^ ^^le Val-de-Travers company engage to lay down their rich asphaltic rock in London at 5/. per ton; and as the mineral tar equal to that of Seissel may probably be had m England at one fourth the price of that foreign article, they may aff^ord to lay their mastich three quarters of an inch thick per the thousand feet, including a sub- stratum of concrete, at a rate of fivepence per square foot, instead of fifteenpence, being the rate charged under that condition by the Bastenne company. These charges are for London and its immediate vicinity. Report of the experimental Pavements laid down in Oxford street, from Charles street to Tottenham Court Road, January, 1839. 1. Robinson's Parisian bitumen, laid in blocks 12 inches square and 5 inches deen- he substance is a compound of bitumen, lime, &c., and five granite stones are inserted hnt kI ^P -^i ^^°'^' -^^ T^^ *' ^*^^ ^" «^^«ig^^ ^o"rses» the joints cemented with W rS"- . T^o ^"^''^'^y ^^ '^'' ^ ^^ «^"*'« y^«i«' '^^ l^^&th is 20 feet, SdTe pnce, if adopted, 9s. per square yard. » » , '"m uie len^h\"'2o''fee't.^"^ ^^^ '°""^' ^^^ diagonaUy. The quantity is 97 square yard,., the 178 BLACK DYE. iM f I 3. Granite paving, 9 inches deep, joined with Clarige's asphalt, the work laid ia straight courses. The cost to the parish has been 11 «. 7 C4 C O by the Pantheon. 347 by Stratford place. 254 by Newman street, j 339 by Stratford place J 371 do. I — >, >s ^ o V e c s 09 09 O 09 9 Hack ages. Hack ages. u o j: • -3 ^ .o _u -•c « be ctf ho IS *. 3 4-* c a> c E O 0) CO r H JS.V3 H O A W 935 890 621 752 91 r2 1507 55] 5 603 1213 401 728 89 472 993 4753 1241 1015 564 1288 85 958 1382 6992 766 1337 542 762 92 i 881 1292 5943 4 1 82 139 21 38 58 324 The asphalt pavements were, in my judgment, so imperfectly constructed with coal tar, ill boiled and aqueous, as to have a crumbling property when exposed to vicissi- tudes of weather. Jiative bitumen makes a far better and more durable cement BLACK DYE. {Teinte noire, Fr. ; Schwartze farbe. Germ.) For 1 cwt of cloth there are put into a boiler of middle size ISlbs. of logwood with as much Aleppo galls m powder, and the whole, being enclosed in a bag, is boiled in a suflScient quantity of water for 12 hours. One-third of this bath is transferred into another boUer with two BLACK DYE. 179 pounds of verdigris ; and the stuff is passed through this solution, stirring it continu- ally during two hours, taking care to keep the bath very hot without boiling. The stuff is then lifted out, another third of the bath is added to the boiler, along with 8 pounds of sulphate of iron or green vitriol The fire is to be lowered while the sul- phate dissolves, and the bath is allowed to cool for half an hour, after which the stuff 18 introduced, and well moved about for an hour, and then it is taken out to air. Lastly, the remaining third of the bath is added to the other two, taking eare to squeeze the bag well. 18 or 22 lbs. of sumach are thrown in ; the whole is just brought to a boil, and then refreshed with a little cold water ; 2 pounds more of sulphate of iron are added, after which the stuff is turned through for an hour. It is next washed, aired, and put again into the bath, stirring it continually for an hour. After this, it is car- ried to the river, washed well, and then fulled. Whenever the water runs off" clear, a bath is prepared with weld, which is made to boil for an instant ; and after refreshing the bath the stuff is turned in to soften, and to render the black more fast In this manner, a very beautiful black is obtained without rendering the cloth too harsh. Commonly more simple processes are employed. Thus the blue cloth is simply turned through a bath of gall-nuts, where it is boiled for two hours. It is next passed through a bath of logwood and sulphate of iron for two hours, without boil- ing, after which it is washed and fulled. But in all cases the cloth, after passing through the blue vat, should be thoroughly washed, because the least remains of its alkalinity would injure the tone to be given in the black copper. Hellot has found that the dyeing might be performed in the following manner: — For 20 yards of dark blue cloth, a bath is made of 2 lbs, of fustic {morm tinctoria), 4i lbs. logwood, and 11 lbs of sumach. After boiling the cloth in it for three hours it is lifted out, 11 lbs. of sulphate of iron are thrown into the boiler, and the cloth is then passed through it during two hours. It is ..ow aired, and put again in the bath for an hour. It is, lastly, washed and scoured. The black is less velvety than that by the preceding process. Experience convinced him that the maddering prescribed in the ancient regulations only gives a reddish cast to the black, which is obtained finer and more velvety without madder. A black may be dyed likewise without having given a blue ground. This method is emplojred for cloths of little value. In this case they are rooted ; that is to say, they receive a dun ground with walnut husks, or the root of the walnut tree, and are afterward ^ made black in the manner above described, or in some other way ; for it is obvious that a black may be obtained by several processes. According to Lewis, the proportions which the English dyers most generally adopt are. for 112 lbs. of woollen cloth previously dyed of a dark blue, about 5 lbs. of sulphate of iroii^ as much gall-nuts, and 30 lbs. of'^logwood. They begin by galling the cloth, they then pass it through the decoction of logwood, to which the sulphate of iron has been added. When the cloth is completely dyed, it is washed in the river, and passed through the fulhng-raill till the water runs off clear and colorless. Some persons recommend, for fine cloths, to full them with soap water. This operation requires an expert work- man, who can free the cloth thoroughly from the soap. Several recommend at its coming from the fulling to pass the cloth through a bath of weld, with the view of giving softness and solidity to the black. Lewis says, that passing the cloth through weld^aft«r it has been treated with soap, is absolutely useless, although it may be benefacial when this operation has been neglected. ^ The following German process is cheap and good. 100 lbs of cloth or wool are put into the copper with sufficient water and 15 lbs. ot Salzburg vitriol (potash-sulphate of iron) and 5 Ihs of argol, heating the bath gradually to boiling, while the goods are well worked about for two hours, taking them out, and laying them in a cool place for twenty-four hours. They are then to be put in a lukewarm bath of from 25 lbs. to 30168. of logwood, and 10 lbs. of fustic, and to be worked therein while it is made to boil during two liouis. The goods are now removed, and there is put into the copper i\i ^V'"^^ ^^r^ 4'^^^^^^^ *" vinegar; the goods are restored iuto the improved batli, and turned in it for half an hour, after which they are rinsed and dried. 1 he process for dyeing merinos black is for 100 lbs. of them to put 10 lbs. of copperas into the bath of pure water, and to work therein for a quarter of an hour, as soon as It 13 tepid one-third of the goods; then to replace that portion by the second, and tiiler another quarter of an hour, to put in the last third. Each portion is to be laid aside tj) air in the cold. The bath being next heated to 140° F., the merinos are to be treated as above piecemeal ; but the third time it is to be passed through the bath at a boiling heat Being now well mordanted, the goods are laid aside to air till the loiiowing day. Ihe copper being charged with water, 60 lbs. of ground logwood and j iiw. of argol, and heated, the goods are to be passed through while boiling for half an hour. They are then rinsed. s »" » -( ^^ 180 BLACK DYE. ' \ I J^ tin?fet-aZ.^ ir^ '° "■"= f ""-f ?he ^ghT'ir .he silk arc less of the whi e gXuteo X^,^ - '"^^''""""■5°^ •■"^"^ *"" ^'"""' "'"'' ""'" " are used. The p?^?S eommJnly emXreS""a,'p» '"1 ^^'°"' "=^7 "^ "'"''« ^'Ib. of the astringent princ^ e but air^otX onhT f ''"^'"' ?<;' ™'^ '■™'» ">« '^''3^' ly fix themselves in proportion ?o the nua^^^itv 1^ ,1 "'T?* Policies, which subsequent- tered into combination. Conseque„urtKDrLe«Jc "stringent principle which had en- of weight which it is wished toToSnicale ?n .h» Mb """^ •""■''iin? lo the degree fflustration. communicate to the silk ; a circumstance requiring Mme The commerce of silk goods ii orrie.) «« .-. . weight, or by the surface, thM if by measure tZ T^'V f^^'.^ '"''' ""•" ^^ "•« distinguished from that of Lyons the sUks „f th J f^rn^J^ k"''* "L^""' '^^ •"o™"'^ the latter, by measure. It was ther/fifr. .1 • • . " ''*'"S '"''' '>>' ^cigl". "><«« of and, on the contrary'to be sTarin. of Z ^V' '" "'^' '» s"charge the weight at Tours, d«.inction of light Wack and healytkckTt^„;"??r!t"^ ^.T'?" ""="« °™«"'« ■^sflk 10^'°"' '1" '7 -"i- »'-'ctvingtSnX.e"d Jh^'''^' °""'''"»" "' ^^ rbLi-rd^d-uA^^iS-i^^^^^^ black, because it is pretS thlt it waT'first orac-'Ju^^^^^^^ T ^^»«°^i'^«ted En.^ish a great surcharge has not a beSul biLk l^.? n""/"?**?^' ^^"*^« ^^'^ dyed with With a warp dyld of a fine bJack ' usually destined for weft, and is blended ^^"^^^^^^^^^ consists in leaving the ber of times throu|h the dye, anS even let tinl ft^il f^ > T''"^ *^^ '^ * greater num- ing is usually made with gaUs which have irvJir '^ ^""^ '°?^ *"""* '^^« ^'-^t ?«»- gaU-nuts are employed for the s^cind R?,t ?i \^ Preceding operation, and fresh giving a great surcLge^sucras °s foun^/n wW ^''^i?^' Tt^ ""' ^' '^^^'^^^^ <*«r it this weight, the silk is caUed wfth on* k^ ^* '^ ''^"^ ^^^ ^"^^'^^ "ack. To give ^T^ ^rr-l^ supiletti^rrked'^; tre^T:'n^ pt' ^"^ ^^'"^'^^ «"^ °^ ^« J ^^et^^S^^^^^^^^^^ varies in di.erent ^c^srii^i^Xi?^^^:^^ time nothing remains of the sever Jin^r^lntlw^^ T' '^ '^^\ ^^ ^^^ ^""^ «^ » <=ertain which are not employed in theTrevet ^""^ composed the primitive bath, but yellow color, is made choice of. U should be rp^u^^'' ?"'P^'^' ''^^> ^^ ^^^ "^t^ve preserve a portion of the gum of the silk wbJ^h r'T^^^>J»^a' when it is desired to w&:^x-5k!^£l-££^^^^^^^^^ U made in the cold, ihhe '^^^TX ^^^^ Slk^Kli Z !^ n.«ie in the cold ; but, aLrding to thTL^ier !?' i" '"^"'"l '» ^ive it. The dye fa Quires more or less time. OccafionaDy th^'e " foiilaf ™^"' "^ '"' ™'''"?^' '' ''■ It B washed, it fa beetled once or twice aid itT, .K» ^^ «« n^essary; after which toflening it *• ""'' " « «*" ^'ed without wringing, to avoid BLACK DYE. 181 Raw Bilk may be more quickly dyed, by shaking it round the rods in the cold bath after the galling, airing it, and repeating these manipulations several times, after which it is washed and dried as above. Macquer describes a more simple process for the black by which velvet is dyed at Genoa ; and he says that this process, rendered still simpler, has had complete success at Tours. The following is his description. For 1 cwt (50 kilogrammes) silk, 22 lbs. (11 kilogrammes) of Aleppo galls, in powder, arc boiled for an hour in a sufficient quantity of water. The bath is allowed to settle till tlie galls have fallen to the bottom of the boiler, from which they are withdrawn ; after which 32 lbs. of English vitriol (or copperas) are introduced, with 13 lbs. of iron-filinga, and 22 lbs of country gum, put into a kind of two-handled cullender, pierced every where with holes. This kettle is suspended by two rods in the boiler, so as not to reach the bottom. The gum is left to dissolve for about an hour, stirring it from time to time. I^ after this time, some gum remains in the kettle, it is a proof that the bath, which contains two hogsheads, has taken as much of it as is necessary. If, on the con- trary, the whole gum is dissolved, from 1 to 4 lbs. more may be added. This cullen- der 18 left constantly suspended in the boiler, from which it is removed only when the dyeing is going on ; and afterwards it is replaced. During all these operations the boiler must be kept hot, but without boiling. The galling of the silk is performed with one third of Aleppo galls. The silk is left in it for six hours the first time, then for twelve hours. The rest, secundum ariem, Lewis states that he has repeated this process in the small way ; and that by adding sulphate of iron progressively, and repeating the immersions of the silk a great number of times, he eventually obtained a fine black. Astringents differ from one another as to the quantity of the principle which enters into combination with the oxyde of iron. Hence, the proportion of the sulphate, or of any other salt of iron, and that of the astringents, should vary according to the astringents made use of, and according to their respective quantities. Gall-nut is the substance which contains most astringent ; sumach, which seems second to it in this respect, throws down (decomposes), however, only half as much sulphate of iron. The most suitable proportion of sulphate of iron appears to be that which corresponds to the quantity of the astringent matter, so that the whole iron precipitable by the as- tringent may be thrown down, and the whole astringent may be taken up in combination with the iron. As it is not possible, however, to arrive at such precision, it is better that the sulphate of iron should predominate, because the astringent, when in excess, counteracts the precipitation of the black coloring particles, and has the property of even dissolving them. This action of the astringent is such that, if a pattern of black cloth be boiled with gall- nuts, it IS reducible to gray. An observation of Lewis mav thence be explained. If cloth be turned several times through the coloring bath, after it' has taken a good black color, instead of acquiring more body, it is weakened, and becomes brownish. Too considera- ble a quantity of the ingredients produces the same effect ; to which the sulphuric acid set at liberty by the precipitation of the oxyde of iron, contributes. ' It is merely the highly oxydized sulphate which is decomposed by the astrin^^ent • whence it appears, that the sulphate will produce a different effect according to its state of oxydizemenl, and call for other proportions. Some advise, therefore, to follow the method of Proust, employing it in the oxydized state ; but in this case it is only partially decomposed, and another part is brought, by the action of the astringent, into the lower aea:ree of oxydizement. The particles precipitated by the mixture of an astringent and sulphate of iron have not at first a deep color; but they pass to a black by contact of air while they are moist. '' Under dyeing I shall show that the black dye is only a very condensed color, and that It assumes more intensity from the mixture of different colors likewise deep. It is for this reason advantageous to unite several astringents, each combination of which produ- ces a different shade. But blue appears the color most conducive to this effect, and it corrects the tendency to dun, which is remarked in the black produced on stufls by the other astringents. •' «.J?,'!rl^'* P'-operty is founded the practice of giving a blue ground to black cloths, which acquire more beauty and solidity the deeper the blue. Another advantage of this prac- nrl-^-f°r ""^ r^t ^ u^ '•y^^'^'^y ""^ sulphuric acid which is necessarily disengaged by the hm Z.ViT 1 ^ ^^,'^ particles and which would not only counteract their fixation, but would further weaken the stuff, and give it harshness. ^1- or^comraon stuffs, a portion of the effect of the blue ground is produced by the iw'fi'lti"'**^"''^ °T* ^°»^<^ ^it^ astringents contributes to the beauty of the black in a iwoiold way. It produces molecules of a hue diflferent from what the astringents do, ii 182 BLACK PIGMENT. BLACK PIGMENT. 183 and particularly blue molecules, with the oxide of copper, commonly employed in the black dyes ; which appears to be more useful the more acetate the verdigris made use of contains. The boil of weld, by which the dye of black cloth is frequently finished, may also contribute to its beauty, by the shade peculiar to its combination. It has, moreover, the advantage of giving softness to the stuffs. The processes that are emplojed for wool yield, according to the observation o/ Lewis, only a rusty black to silk ; and cotton is hardly dyed by the process propei for wool and silk. Let us endeavor to ascertain the conditions which these three varie- ties of dyeing demand. Wool has a great tendency to combine with coloring substances ; but its physical nature requires its combinations to be made in general at a high temperature. The combination of the black molecules may therefore be directly effected in a bath, in proportion as they form ; and if the operation be prolonged by subdividing it, it is only with the view of changing the necessary oxidizement of the sulphate, and aug- menting that of the coloring particles themselves. Silk has little disposition to unite with the black particles. It seems to be merely by the agency of the tannin, with which it is previously impregnated, that these particles can fix themselves on it, especially after it has been scoured. For this reason, silk hatha should be old, and have the coloring particles accumulated in them, but so feebly sus- pended as to yield to a weak affinity. Their precipitation is counteracted by the addi- tion of gum, or other mucilaginous substances. The obstacles which might arise from the sulphuric acid set at liberty is destroyed by iron filings, or other basis. Thus, baths of a very different composition, but with the essential condition of age, may be proper for this dye. For cotton black dye, see Calico Printing. Blue-bldck dye. — The mordant much employed in some parts of Germany for this dye, with logwood, galls, sumach, ossessed of peculiar properties. It is generally admitted at the present day, that a portion of the oxygen of the air passes into the coloring matter, and changes its con- BLEACHING. 186 Btitution. This is, however, probably not the part which oxygen plays, nor is it the only principle in the atmosphere which exercises a bleaching influence. Neither is the action of chlorine such as has been commonly represented in our chemical systems. But if authors offer us only vagjiie hypotheses concerning the three principal agents, light, oxygen, chlorine, they afford no information whatever concerning the phenomena due to sreasy spots so frequently found upon cotton cloth, and so very tnmblesome to the bleacher. It has indeed been sometimes said in bleach-works, that fatty sub- stances are no longer soluble in alkalis, wheff they are combined with oxygen. The very reverse of this statement is probably nearer the truth. The object of bleaching is to separate from the textile fibre, by suitable operations, all the substances which mask its intrinsic whiteness : or which, in the coui-se of ulterior dyeing operations, may produce injurious effects. In this latter respect, cotton deserves especial consideration. This substance is covered with a resinous matter, which obstructs its absorption of moisture, and with a yellow coloring matter in very small quantity, often so inconsiderable in some cottons, that it would be unnecessary to bleach them, before submitting them to the dyer, were it not that the manipulations which they undergo introduce certain impurities which are more or less injurious, and must be removed. It is in fact a circumstance well known in the factories, that unbleached cottons may be dyed any dark color, provided they are deprived of that matter which makes them difficult to moisten. The substances present in couon goods are the following : — 1. The resinous matter natural to the cotton filaments. 2. The proper coloring matter of this vegetable. 3. The paste of the weaver. 4. A fat matter. 5. A cupreous soap. 6. A calcareous soap, 7. The filth of the hands. 8. Iron, and some earthy substances. 1. The matter which prevents the moistening of cotton wool may be separated by means of alcohol, which, when evaporated, leaves thin yellowish scales, soluble in alkalis, in acids, and even in a large quantity of boiling water. For a long time the bleaching process commenced with the removal of this resinous stuff, by passing the cloth or the yarn through an alkaline ley. This was called scouring ; it is now nearly laid aside. 2. The coloring matter of cotton seems to be superficial, and to have no influence on the strength of the fibres ; for the yarn is found to be as strong after it has been stripped by caustic soda of its resinous and coloring matters, as it was before. The coloring matter is slightly soluble in water, and perfectly in alkaline leys. When gray calico is boiled in lime-water, it comes out with a tint darker than it had before; whence It might be supposed that the coloring matter was not dissolved out, even in part. This, however, is not the case ; for if we filter the liquor, and neutralize it with an acid, we shall perceive light flocks, formed of the resinous substance, united with the coloring matter. The dark color of the cloth is to be ascribed solely to the property which lime possesses of browning certain vegetable colors. This action is here exercised upon the remaining color of the cloth. It may be laid down as a principle, that the coloring matter is not directly soluble by the alkalis ; but that it becomes so only after having been for some time exposed to the joint action of air and light, or after having been in contact with chlorine. What change does it thereby experience, which gives it this solubility ? Experiments made upon pieces of cloth placed in humid oxygen, in dry oxygen, in moist chlorine, and in dry chlorine, tend to show that hydrogen is abstracted by the atmosphere ; for in these experiments proofs o£ dis-hydrogenation appeared, and of the production of carbonic acid. In all cases of bleaching by chlorine, this principle combines immediately with the hydrogen of the coloring matter, and forms muriatic acid, while the carbon is elimi- nated. Undoubtedly water has an influence upon this phenomenon, since the bleaching process is quicker with the humid chlorine than with the dry ; but this liquid seems to act here only mechanically, in condensing the particles of the gas into a solution. We should also take into account the great affinity of muriatic acid for water. 3. The weaver's dressing is composed of farinaceous matters, w^hich are usually allowed to sour before they are employed. It may contain glue, starch, gluten ; which last is very soluble in lime-water. 4. When the dressing gets dry, the hand-weaver occasionally renders his warp-threads more pliant by rubbing some cheap kind of grease upon them. Hence it happens, that the cloth which has not been completely freed from this fatty matter will not readily imbibe water in the different bleaching operations ; and hence, in the subsequent dyeing or dunging, these greasy spots, under peculiar circumstances, somewhat like lithosrraphic stones, strongly attract the aluminous and iron mordants, as well as the dye-slufffi, and 186 BLEACHING. BLEACHING. 187 occasion stains which it is almost impossible to discharge. The acids act differently upon the fatty matters, and thence remarkable anomalies in bleaching take place. When oil is treated with the acetic or muriatic acid, or with aqueous chlorine, it evolves no gas, as it does with the sulphuric and nitric acids, but it combines with these substances so as to form a compound which cannot be dissolved by a strong boiling ley of caustic soda. Carbonic acid acts in the same way with oil. On the other hand, when the oils and fats are sufficiently exposed to the air, they seize a portion of its oxygen, and become thereby capable of saponification, that is, very soluble in the alkalis. 5. When the hand-weaver's grease continues in contact for a night with the dopper dents of his reed, a kind of cupreous soap is formed, which is sometimes very difficult to remove from the web. Lime-water does not dissolve it ; but dilute sulphuric acid carries off the metallic oxyde, and liberates the margaric acid, in a state ready to be acted on by alkalis. 6. When cloth is boiled with milk of lime, the grease which is uncombined unites with that alkaline earth ; and forms a calcareous soap, pretty soluble in a great excess of lime-water, and still more so in caustic soda. But all fats and oils, as well as the soape of copper and lime, cease to be soluble in alkaline leys, when they have remained a con- siderable time upon the goods, and have been in contact with acetic, carbonic, muriatic acids, or chlorine. These results have been verified by experiment. 7. Cotton goods are sometimes much soiled, from being sewed or tamboured with dirty hands ; but they may be easily cleansed from this filth by hot water. 8. Any ferruginous or earthy matters which get attached to the goods in the course of bleaching, are readily removable. We are now prepared to understand the true principles of bleaching cotton goods, for the most delicate operations of the calico printer. 1. The first process is steeping, or rather boiling, the goods in water, in order to re- move all the substances soluble in that liquid. 2. The next step is to wash or scour the goods by the dash-wheel or the stocks. This is of great importance in the course of bleaching, and must be repeated several times; so much so, that in winter, when the water of the dash-wheel is cold, the bleaching is more tedious and difficult. Yarn and very open fabrics do not much need the dash- wheel. By these first two operations, the woven goods lose about sixteen per cent, of their weight, while they lose only two parts out of five hundred in all the rest of the bleaching. 3. In the third place the calicoes are boiled with milk of lime, whereby they are stripped of their gluten, and acquire a portion of calcareous soap. Formerly, and still in many bleach-works, the gluten was got rid of by a species of fermentation of the farinaceous dressing ; but this method is liable to several objections in reference to the calico printer. 1. The fermentative action extends sometimes to the goods and weakens their texture, especially when they are piled up in a great heap without being previously washed. 2. The spots of grease, or of the insoluble soaps, become thereby capable of resisting the caustic alkalis, and are rendered in some measure indelible ; an effect due to the acetic and carbonic acids generated during fermentation, and which will be easily understood from what has been said concerning the action of acids on fatty substances. It Ls not, therefore, without good reason that many practical men throw some spent leys into the fermenting vats, to neutralize the acids which are formed. Were it not for the presence of fat, fermentation, skilfully conducted, would be an excellent means of car- rying off the gluten; and the steep is therefore applicable to power-loom goods, which are not polluted with grease. 4. The goods are now subjected to a caustic soda ley, which dissolves out the soaps of lime and copper, as well as that portion of the coloring matter which is sufficiently dis-hydrogenated to be capable of combining with it. This bucking with ley, which is repeated several times upon the goods, in order to purge them completely from the fatty matter present in the hand-loom webs, and also partidly introduced in the spinning, is almost the only operation to which yarns for Turkey red are subjected. After being boiled in a caustic soda ley, they are passed through solutions of chloride of lime, and afterwards through the acid steep. 5. When the goods are sufficiently bucked in the leys, they are eitter exposed to chlorine, or laid out on the grass ; sometimes both are had recourse to for delicate work. These different modes of action have the same influence on the coloring matter, but they give rise to different effects in reference to greasy stains. The goods are dipped in a solution of chloride of lime, which should be kept tepid by means of steam. Alongside of the chlorine cistern, there is another filled with dilute sulphuric or muriatic acid. When the goods are taken out of the chlorine, they are drained on the top of its cistern till no more liquid runs off them, and they are then plunged into the sour. The action of the acid in the present case may be easily ex- plained. In proportion as a salt of lime is formed, this base quits the chlorine, and allows it to act freely upon the coloring matter. Thus we prevent the development of too great a quantity of chlorine at once, which would be apt to injure the fibres; and we pursue both a prudent and economical plan. Only so much chlorine as is strictly necessary is called forth, and hence it excites no smell in the apartment. • r • ». The chlorine serves to acidify the coloring matter, by abstracting a portion of its hy- drogen; but we must lake the greatest care that there is no grease upon the goods before immersion in it, for the consequence would be, as above shown, very troublesome spots. When the cloth is laid out upon the grass, it is the oxygen of the air which acidifies the coloring matter ; for which reason, the dew, which contains much air rich in oxygen, sin- gularly^accelerates the bleaching process. It is likewise, by absorbing oxygen from the atmosphere, that fats or oils pass to the state of margaric and oleic acids, and become most easily saponified. Should the goods, however, be left too long on the grass, the faU absorb carbonic acid, and become insoluble in leys. 6. The goods must now receive a new soda ley, to dissolve out that portion of the coloring matter which has been dis-hydrogenated in the chlorine of the air, as well as the grease, if any perchance remained in the soluble state. These last two operations are to be several times repeated, because the coloring matter should be removed only by degrees, for fear of injuring the texture of the goods, by subjecting them to too much chlorine at a time. 7. We finish with the dilute sulphuric acid, which should be very weak and tepid. It dissolves out the iron, and some earthy matters occasionally found upon cotton. The goods must be most carefully washed at the dash-wheel, or in a stream of water on quit- ting the sour ba h, for if the acid were allowed to dry in them, it would infallibly injure their texture by its concentration. In winter, if the goods are allowed to get frozen with the acid upon them, they may likewise be damaged. We may here observe, that when the goods are not to remain white, their bleaching may be completed with a ley ; for though it leaves a faint yellow tint, this is no incon- venience to the dyer. But when they are to be finished with a starching after the last ley, they must have another dip of the chlorine to render the white more perfect. An immersion in the dilute acid has nearly the same effect. The principles expounded above lead to this important consequence, that when we wish to bleach goods that are free from greasy stains, as is the case generally with the better kinds of muslins, or when we wish to bleach even greasy goods for the staieh finish, we may content ourselves with the following operations : — 1. Boiling in water. 2. Scouring by the stocks or the dash-wheeL 3. Bucking with milk of lime. 4. Passing through chlorine, or exposure on the grass. 5. Bucking, or bouking with milk of lime. These two latier operations require to be alternated several times, till the whole of the coloring matter be removed. 6. Souring. The bleaching of goods, which are never laid down on the green, and which are not dried between two operations, may be conipleled in a couple of days. They answer as well for the printer as the others, and they are as white. Cotton fibres or yarns suffer no diminution of their strength, when the cloth has been properly treated in the above described processes. Accurate experiments hare demonstrated that their strength is not impaired by being boiled in milk of lime for two hours at the ordinary pressure, provided thcv be constantly- kept covered with liquid during the whole ebuUilion, and that they be well washed im- mediately afterwards ; or, by being boiled in pure water under the pressure of ten atmos- pheres of steam; or by being boiled under the same pressure in a caustic soda ley, mark- ing 3° of Tweedale, or specific gravity 1*015, though it has increased to double the density in the course of the boil, by the escape of the steam ; or by being boiled nnderthe atmos- pheric pressure at 14° of Tweedale, or specific gravity of 1*070 ; or by being immersed for eight hours in chloride of lime, capable of decoloring three times its bulk, of test so- lution of indigo (See Chlorine) ; and by being afterwards dipped in sulphuric acid of specific gravity 1-067, Tweedale 14° ; or by being steeped for eighteen hours in sulphu- ric or muriatic acid of specific gravity 1*035, 7° Tweedale. In other well-conducted bleach-works the following is the train of operations : — 1. Cleansing out the weaver's dressing by steeping the cloth for twelve hours in cold water, and then washing it at the stocks or the dash-wheel. 2. Boiling in milk of lime, of a strength suited to the quality of the goods, but for a shorter time than with the soda ley; two short operations with the lime, with intermediate washing, being prefer- able to one of greater duration. 3 and 4. Two consecutive leys of ten or twelve hours* boiling, with about two pounds of soda chrystals for 1 cwt. of cloth. 5. Exposure to the air for six or eight days, or the application of the chloride of lime and the sulphuric k _J 1^ h: LI : in 186 BLEACHING. acid. 6. A ley of caustic soda, like the former, sometimes with less alkali. 7. Exposure to the air for six or eight days, or chlorine and the sour, as above. 8. Caustic soda ley, as before. 9. Chlorine and the sour. 10. Rinsing in hot water, or scourine at the dash-wheel. If the numoer of vessels to be heated exceeds four or five, there is an economy in using steam as the medium of heat ; but under this number there is an advantage in the direct application of fire to a boiling or bucking apparatus; since when only two vessels are in activity, there is a waste of fuel by the extra steam power. It deserves to be remarked, also, that the increase of the bulk of the liquid by the condensation of the steam, does not permit the spent white ley to be turned to use for the green goods, on ac- count of Its excessive dilution. With the milk of lime boil, however, this dilution would be rather an advantage. Tt has been found that the introduction of bran into the fermenting steep (when this is used) endangers the texture of the goods, by causing a putrefactive fermentation in some places. When in the milk of lime boU there is too much of this caustic earth, or when it is poured in on the top of the goods, they are apt to suffer damage. The milk of lime should be introduced from beneath into the under compartment of the bucking apparatus. For the same reason, after the caustic soda ley, the vessel should be filled up with water, if the goods be not immediately transferred to the dash-wheel. When they are allowed to become partiaUy dry on the top, they are easily injured. The copper of the bucking ap- paratus ought to be of a size proportioned to that of the surmounting crib or vat ; for when It IS too small, the liquid is too long of being brousrht into proper circulation, and the goods may be meanwhile injured. In a bucking apparatus, which requires five or six homrs to be brought into fuU play, those goods are very apt to be injured, which Ue im- mediately under the overflow pipe. AVhen the chbride of lime steep is too strong, sometimes small round holes are made in the calico, just as if they had been cut out by a punch, especially in the borders or thicker parts of the goods. This accident is owing to the presence of bubbles of chlorine, l-rom the saturated state of the Hquid, they remain gaseous a sufficient length of tune for corroding the parts of the cloth with which they are in contact. These will be obviously the denser parts, for they confine the gas most completely, or prevent its difl'usion through tne mass. I his evil is prevented by diluting the chloride steep to the proper degree, and moving the goods through it. i- *- *• o , The greasy spots, described above, show themselves in the maddering by attracting the dye-stuff more copiously than the pure parts of the cloth, so as to mottle it ; they are also recognised in the white goods by being somewhat repulsive of moisture. When the com- bmation of fatty matters with chlorine takes place at the surface of cotton goods, it is of a nature to resist the action of alkalis. It is the stearine, or the principle of suet, par- ticularly, which, by this means, acquires such a strong affinity for cottons ; the elaine, or the principle of oils, has no such remarkable affinity. Lime, in some circumstances, seems to act as a mordant to greasy matters, and to fix them fast. Hence the weaver snould be prohibited, m all cases, from allowing candle-grease to touch his web. Goods soiled with it should never be allowed to lie by in the^ware-house, but be immediately cleansed before the air has fixed the stearine by converting it into margaric acid. Lime snould, m these cases, be prudently employed ; chlorine should never be used till the greasy stains are thoroughly removed; and the bleacher should never warrant his pieces for the printer till he has verified some of them by the water test. I shall conclude this general analysis of the principles of bleaching by a few precepts. Avoid lime, at the first ley, for goods which contain creasy spots ; but use It ireeJy atler one or two soda leys, and apply two soda leys after it. Do not apply chlorine between these leys, but reserve it for the final operation. By this plan the goods will be well bleached and very little worn. Use the souring steeps freely, ^'J-"?*i. ^"^'" ^^*^^ ^^y* whether of lime or soda, since the calcareous base, with which the greasy spots get charged merely from hard water, is an obstacle to the further action of the leys. I shall now give some practical instructions concerning the several steps of the bleach- ing process, as applied to cotton, linen, silk, and wool. The first thing which the cotton bleacher does, is to mark the pieces with the initials of the owner, by means of a stamp imbued with coal tar. The linen bleacher marks with nitrate of silver, a far more expensive substance, but one which resists better the severer treatment which his goods are destined to undergo. The cotton goods are generally singed before they are sent to the bleacher, and this is done either by passing them rapidly over a red-hot semi-cylinder of iron, or over a row of gas flames, by Mr. HaU's ingenious contrivance. (See Singeing.) Each piece is next creased together lengthwise like a rope, folded into a bundle, and fixed by a noose at the end. In this open state it is easily penetrated by the water of the soaking cistern into Which it is thrown. It is then scoured by the dash or wash-wheel. It is now ready foi BLEACHING. 189 the bucking or steaming apparatus, where it is treated with milk of lime. The steam chamber resembles the bucking vessel, without its bottom copper; that is to say, a few inches below the grated bottom of the bucking tub, there is a close iron sole, through the centre of which the steam is admitted by several small apertures, for the purpose of dliff'using it throughout the goods, and causing a liquid circulation by its pressure, as the steam does in the proper bucking boiler. One pound of lime previously made into n cream consistenced mixture, and passed through a sieve, is used for every thirty or forty pounds of cloth, according to its color and texture ; and this cream mixed with more water IS interstratified with the pieces, as they are laid regularly in the vessel. Whenever this is stocked with goods, all their interstices are filled up with water. After the lime bucking, the cloth is transferred to the dash-wheel. A pound of cloth requires for its whitening about half a pound of good average chloride of lime or bleaching powder, as it is commonly called, and this ought to be dissolved in about three gallons of water. Mr. Crum of Thorniebank, near Glasgow, an extensile and* excellent bleacher, has so modified Dr. Dalton's ingenious plan of testing the power of bleaching liquors by green sulphate of iron, as to give it much greater precision for the bleacher's use, than the discoloration of indigo originally pro- posed by Berthollet. Mr. Crum dissolves four ounces of fresh green vitriol in hot water, and then adds the solution of bleaching powder by small quantities at a time, till the iron becomes wholly peroxydized, when the smell of chlorine will become perceptible. When the bleacher has once found by trial the proper blanching power which his chlorine steep ought to have, he can verify its standard, by seeing how much of it must be added to an ounce, or any given weight of fresh copperas, dissolved in hot water, to cause the peroxydizement and the exhalation of the peculiar odor. M. Gay Lussac's new method by arsenious acid will be described under chlorine. From the experiments which I made some years ago,* upon indigo, it will be seen that this dye stuff is so variable in its quantity of coloring matter, that no two chemists operating with it independently, as a test for chloride of lime, could arrive at the same result. They must provide themselves with absolute indigo, by an expensive and troublesome process, not suited to the busy bleacher. The vitriolage, as the French term it, or the souring of the English bleacher, consists in immersing the goods for four hours in dilute sulphuric acid, con- taining one gallon of oil of vitriol to from 25 to 30 of water, thoroughly intermixed by stirring ; for the density of the acid is an obstacle to its equal distribution through the water. This dilute acid will have a density of from 1047 to 1*040, and will contain from 7 to 6| per cent, by weight of the oil of vitriol. The goods are now washed, and then boiled for eight or nine hours in an alkaline ley, containing about two pounds of crystals of soda, or their equivalent in soda ash or pearl-ash, for every 100 lbs. of cloth. The ley must be made previously caustic by quick lime. A washing in the wheel follows this boil ; and then a chlorine steep for five hours in a liquor two thirds of the strength of the former. It is next soured in the dilute sulphuric acid, for two, three, or four hours, according to the color and quality of the cotton, and then thoroughly washed. The cloth is now bleached white, but cannot be presented in the market till it undergoes certain finishing processes. The piece is elongated from the folds which it contracts during the rotation of the dash-wheel by being thrown into a stream of water in a cistern, terminated by the squeezing rollers, which take in the end of the piece, and run it through between them, with the effect of making it nearly dry. Two pieces of cloth pass simultaneously through the rollers, and are disentangled spontaneously, so to speak, without the help of hands. The squeezing rollers or squeezers, for discharging the greater part of the water from the yarns and goods in the process of bleaching, are represented in Jigs. 130, 131, the 131 "3 * Quarlerlx Journal of Science, Literature, and the Art», vol. vii. p. 160 l^ 190 BLEACHING. BLEACHING. 191 f former being a side-view, to show how the roller gudgeons lie in the slots of the fram^ and how the shaft of the upper roller is pressed downward by a weighted lever, through a vertical junction rod, jointed at the bottom to a nearly horizontal bar, on whose end the proper weight is hung. In yig. 118, these rollers of birch- wood are shown in face ; the under one receiving motion through the toothed wheel on its shaf\, from any suitable power of water or steam. Upon the sliafi of the latter, between the toothed wheel and the roller, the lever and pulley for putting the machine into and out of gear are visible. The under roller makes about 25 revolutions in the minute, in which time three pieces of goods, stitched endwise, measuring 28 yards each, may be run through the machine, from a water trough on one side, to a wooden grating upon the other. When the goods are run through, they are carried off upon a grated wheelbarrow, in a nearly dry state, and transferred to the spreading machine, called at Manchester a candroy. In many bleach-works, however, the creased pieces are pulled straight by the hands of women, and are then strongly beat against a wooden stock to smooth out the edges. This being done, a number of pieces are stitched endwise together, preparatory to being mangled. Calender. — Fig. Fiews broken off. 132 is The goods 132 cross section of this machine, and Jigs. 133, 134, are front are first rolled npon the wooden cylinder o, near the 133 134 ground; by the tension roller 6, upon the same cylinder, the goods receive a proper degree of stretching in the winding off. They then pass over the spreading bars c c c, by which they are still more distended ; next round the hollow iron cylinder^ rf, 16 inches diameter, and the paper cylinder e, of like dimensions ; thence they proceed under the second massive iron cylinder /, of 8 inches diameter, to be finally wound about the pro- jecting wooden roller g. This is set in motion by the pulleys h,fig. 121, and i,fig. J20, and receives its proper tension from the haneing roller k ; I is a. press cylinder, of 14 inches diameter, made^of plane-tree wood. By its means we can at all times secure an equal deeree of pressure, which would be hardly possible did the weighted lever press immediately upon two points of the calender rollers. The compression exercised by the cylinders may be increased at pleasure by the bent lever m, weights being applied to it at n. The upper branch of the lever o is made fast by screws and bolts at ;>, to the upper press-cylinder. The junction leg q is attached to the intermediate piece r, by left and richt-handed screws, so that according as that piece is turned round to the right or the left, the pressure of the weighted roller will be either increased or diminished. By turning it still more, the piece will get detached, the whole pressure will be removed, and the press-roller may be taken off; which is a main object of this mechanism. The unequable movement of the cylinders is produced by the wheels s t u, of which the undermost has 69, the uppermost has 20, and the carrier-wheel /, either 33, 32, or 20 teeth, according to the difference of speed required. The carrier-wheel is bolted on at V, and adjusted in its proper place by means of a slot. To the undermost iron cylinder, the first motion is communicated by any power, for which purpose either a rigger (driving pulley) is applied to its shaft at «, or a crank motion. If it be desired to operate with a heated calender, the undermost hollow cylinder may be filled whh hot steam, admitted through a stufiing-box at one end, and discharged through a stuffing-box at the other, or by a red-hot iron roller. Pure starch would be too expensive a dressing for common calico shirtings, and there- fore an extemporaneous starch is made by mixing one pound of flour with one gallon of water, and aUowing the mixture to ferment in a warm place for twenty-four hours. In this way, a portion of lactic acid is formed, which dissolves the gluten, or separates it from the starch ; so that when the whole is thrown upon a sieve, a liquid paste passes through, which, being boiled, answers well for stiffening the goods, without giving them a gray tinge. The paste is thinned with water to the desired degree, and faintly tinged with solution of indigo. The starch, which is sometimes thickened with porcelain clay, Paris plaster, or Spanish white, is put into a trough, and is evenly imparted to the cloth as this is drawn down through it, by the traction of rollers. There is a roller near the bottom of the trough, round which the cloth is made to run, to secure its full impresna- tion ; while the upper rollers serve to expel its excess of the starch, and throw it back mto the cistern. See Starching Apparatus. The goods are next dried in an apartment heated by two, three, or more flues, running along the floor, and covered usually with fire-tiles. At fiist the heat is moderate, but it is gradually raised to upwards of 1 10° F. The goods must now be passed again through the calender, in order to receive their final smoothness and lustre. They are, in the first place, damped with a peculiar ma- chine, furnished with a circular brush, whose points revolve in contact with water in a trough placed beneath them, and sprinkle drops of water upon the goods as they are drawn fon\^ard by a pair of cylinders. They are then subjected to the powerful pressoie of the calender rollers. The calendered pieces are neatly folded into compact parcels, and stamped with the marks of each particular manufacturer, or various devices to suit the markets for which they are designed. They are finally piled on the sole of an hydraulic press, with a sheet of pasteboard between each piece; but with occasional plates of iron to secure uniformity of pressure throughout. When sufficiently condensed by the press, they are taken out, and despatched to their respective manufacturers in a state ready for sale. There are no less than 25 steps in the bleaching of calicoes, many of them effected with expensive machinery ; yet the whole do not produce to the bleacher more than 10 pence per piece of 24 yards. The following system was pursued, a few years back, by a skilful bleacher of muslins near Glasgow : — " In fermenting muslin goods, we surround them with our spent leys, from the tem- perature of 100° to 150° F., according to the weather, and allow them to ferment for 36 hours. In boihng 112 lbs. = 112 pieces of yard-wide muslin, we use 6 or 7 lbs of pearl-ashes, and 2 lbs. of soft soap, with 360 gallons of water, and allow them to boil for 6 hours ; then wash them, and boil them again with 5 lbs. of pearl-a"^ ."■^'*,.^.^^''};"^.l^y^°^a ' f'^l''^'^- 'P''^ -"^''"'y °^ «^"t 10254 at the temper- fTilf>lf «^^^^'-f»^^»t- .J^ bleaching common goods, and such as are not designed of 1 nl^« r^w i?!l '^l '^ll'^^^^'-^'y of the sours is varied from that of 1-0146 to that of 1-0238, If weighed when they become of the temperature of the atmosphere. In these they are suff-ered to he for five or six hours, after which they are taken to the dash-whed and washed thoroughly. When this operation is finished, theyare submUted to four more bodings as before, wiih a solution of caustic potash; taking care to Tash weU betw^^ ^ch of these boilings Sometimes pearl-ash, made caustic, is used frtheTast of JhSe ^eZfi^'' ThVv" ?"' T''"' ^^"Y^ 'T^V? '''' P«^^^^- of commerce shTuW iii^pS tne whites. They are next immersed m the diluted chloride of potash, of the strength rnrZ^rT""'^'' ^^''' ^^^^'^ '^'^ "^ ^^^^ ^^«hed in pure wa?er and then wiS of li *" ^"' V" '"'T^u^ ^'^'•'- "^^^ ^^^t P^«<^^ss is that of carefil wasWn^ in pleu^ of clean water after which they are not put into the stove, but are immediSefy hung u^ in the airing sheds to dry gradually. The water must be good, and abundant.^ ^ ^ The number of operations, as here described, is great ; but I know of no other mode ~ wiTho^t'd'"' ''''r ''I'^f'''' '' '' ^^^^'^° ^^ ^ff-t-'i at aU times anS inl seasons, without disappointment. It must here be remarked, that, for the best ouroos^ of printmg, it would not be sufficient to take goods wWch have been bleached^Th" « nrint.r ^if • ^J' .^hat Operation will be apt to spoil them for madder colors at leaTt. a pr nter who is curious m his business would hesitate to work up such cloth ' ^ of wf coft^ f rfeo?.? 'Tu' '' ^'^ "^^^ ,^P«^^^^^ «P-' ^-- ^^^ bleaching remained on the cloth for some S^e it L nTn of? k''^ T^ ^^' ^''^'''''' ^^' ^^^^^8 kleve, into an iron boiler surS in The ^rS^S fr ^ I ^^op-cock, at the bottom of th? by a ^ump. The hea Ts now devat JJ^ « h'- k"^ .^^^''''^ '^ '^ "^'^'^ ^^^^ ^^'^ boiler upon the goods irthekTeveTn,^ wh ^'^f^^ ^^^ ^^^ again run d^cribed : and these oneralfo'nsar? ^nt"'^ ? '', '"'""^"^ ^°^° '^^ ^'^^^ ^^ before alkaline ley is compleX .Zrated ^TT^ f""-^^' increasing the heat, until the which is known byT l^^vin- arnnlr^ » ^ ''"^"r^ T^'^' ^^^^"^ ^^^"^ the cloth, causticity. ^ ^ *^^"''^ ^ completely off-ensive smell, and losing its rnZ:\:L^lft,l%^^^^ upon colored vegetable increased. Thus, when ^eSle subst--!^^ '^^ •V'^ 'l"'^"'^^ ^^^ ^^^"^ ^^^ually the coloring mattVr, in placf of be n ' ext aLTis b^^^^ T ^"^"^^ ^'^^*^' •mo them. It is on this principle that a cook n^I ■' ^I **»'^.b»Sher temperature, fixed color of vegetables is intend^ tVbepeseTved -i^nlL ^" i^^'^,,^'^' 7^^^^ ^^e green cold, tliey are kept back until the w^tPr TJ wr ^T °^ P"^^'''^ '^^"^ ^^« "^^^^^ ^hen the former case, he -reen color wm,MK .'^f^ ' ^^'^^""^ '^ ^ ^^^ ^nown that, in bles are not infised ,!nS"the tat^rf^^^^^^^^^ tT'''^' ^"I'^T' "^^" ^^^ ^'^^^^- On the same principle when thp t.ml ♦ "' the color is completely preserved or fixed, extractive and col, r^ng matter is ZIT.? n ^^'l^^^^^'^^^ ^'Y ^^ ^adually raised, the reversed when the ley rappl fed ^thf Wi ^ l^^''' ^'^"^ *^^ *^^°'^' ^"^ *^« ^^^^ « which has been so unfortunate a An mjl? ^'^'i^'J?. temperature : so much so, that linen t-ood white. ""^oriunate as to meet with this treatment, can never be brought to a When the alkaline ley is saturated with coloring matter, it is run off as unfit for 194 BLEACHING. BLEACHING. / i \: [ ' It la Jig- further use in this operation ; but, were the goods to be instantly taken out of the kieve, and carried to be washed in the dash-wheel while hot, a certain portion of the coloring matter would be again fixed into ihera, which is extremely difficult to eradicate. In order to prevent this, the most approved bleachers run warm water upon the cloth as soon as the impure ley is run off: this combines with and carries ofl'part of the remaining impurities. A stream of water is then allowed to run upon the cloth in the kieve, until it comes off almost transparent. The goods are now to be taken to the wash stocks, or to the dash-wheel, to be further cleaned, with the greatest efficacy. The improved mode of bowking was the invention of Mr. John Laurie, a native of Glasgow. It is now practised by many bleachers in Lancashire, some on more perfect plans than others ; but we shall give the description of the kind of apparatus approved of by those whose experience and skill have rendered them the roost competent judges. B c o is the wooden kieve, or kier, containing the cloth; c e f i> represents the cast-iron boiler ; g g, the pump; g K, the pipe of communication between the kieve and the boiler. This pipe has a valve on each of its extremities ; that on the upper extremity, when shut, prevents the ley from running into the boiler, and is regulated by the attendant by means of the rod and handle g b. The valve at k admits the ley ; but, open- ing inwards, it prevents the steam from escaping through the pipe g K. The boiler has a steam-tight iron cover, g l; and at c d, in the kieve, is a wooden grating, a small distance al>0Te the cover of the boiler. At M o is a broad plate of metal, in order to spread the ley over the cloth. It is hardly necessary to say that the boiler has a furnace, as usual, for similar purposes. While the ley is at a low temperature the pump is worked by the mill or steam- engine. When it is sufficiently heated, the elasticity of the steam forces it up through the valves of the pump, in which case it is disjoined from the moving power. N p is a copper spout, which is removed at the time of taking the cloth out of the kieve. The boQers a, Jig. 136, used in bleaching, are of the common form, having a stop. cock, H G, at bottom, for running off the waste ley. They are commonly made of cast-iron, and are ca- pable of containing from 300 to 600 gallons of water, according to the extent of the business done. In order that the capacity of the boilers maybe enlarged, they are formed so as to admit of a crib of wood, strongly hooped, or, what is preferable, of cast-iron, to be fixed to the upper rim or edge of it. To keep the goods from the bottom, where the heat acts most forcibly, a strong iron ring, covered with netting made of stout rope, c, is allowed to rest six or eight inches above the bottom of the boiler. Four double ropes are attached to the ring e, for with- drawing the goods when sufficiently boiled, which have each an eye for admitting hooks from the running tackle of a crane. Where more boilers than one are employed, the crane is so placed, that, in the range of its sweep, it may withdraw the goods from any of them. For this purpose, the crane turns on pivots at top and bottom ; and the goods are raised or low- ered at pleasure, with double pulleys and sheaves, by means of a cylinder moved by cast- iron wheels. The lid is secured by the screw bolts d d, and rings b b. f is a safety valve. The efficacy of Laurie's bowking apparatus is remarkable. While the heat is gradually rising, a current of fresh ley is constantly presented to the difierent surfaces for saturating the goods, so as to increase its detersive powers. Besides, the manner in 195 which the apparatus is worked, first by the water-wheel or steam-engine, and then by its intrinsic operation, puts it completely out of the power of servants to slight the work- not to speak of the great saving of alkali, which, in many cases, has been found to amount to 25 per cent. A simple modification of the bowkmg apparatus is shown in Jigs. 137, 138, 139 ; the first being a vertical section, the second, a horizontal section in the line X of the first. It consists of two parts: the upper wide part, a a, serves for the reception of the goods, and the lower or pot, b, for holding the ley ; c c is an iron grating, shown apart in^g. 139, The grating has numerous square apertures in the middle of the disc, to which the rising pipe d is screwed fast. The upper cylinder is formed of cast iron, or of sheet iron well riveted at the edges ; or sometimes of wood, this being secured at its under edge into a groove in the top edge of the ley- pot. The mouth of the cylinder is constructed usually of sheet iron, e « is the fire-grate, whose upper surface is shown in^g. 138 ; it is made of cast iron, in thi ee pieces. The flame is parted at/, and passes through the two apertures g g, into the flues A A, so as to play round the pot, as is visible in^g. 138 ; and escapes by two outlets into the chimney. The apertures i i serve for occasionally sleaning out the flues h h, and are, at other times, shut with an iron plate. In the partition /, which separates the two openings g g, and the flues h h, running round the pot, there is a circular space at the point marked with kyjig. 138, in which the large pipe for dischai^ing the waste ley is lodged. The upper large cylinder should be incased in wood, with an intermediate space filled with saw- dust, to confine the heat. The action of this appa- ratus is exactly the same as of that already explained. Besides the boiling, buckinsr, and other appa- ratus above described, the machinery and utensils used in bleaching are various, according to the business done by the bleacher. When linen or heavy cotton cloths are whitened, and the business is carried on to a considerable extent, the machines are both complicated and expensive. They con- sist chiefly of a water-wheel, sufficiently powerful for giving motion to the wash-stocks, dash-wheels, squeezers, &c., with any other operations where power is required. Figs. 140, 141, represent a pair of wash-stocks. A A are called the stocks, or feet. They are sus- pended on iron pivots at b, and receive their mo- tion from wipers on the revolving shaft c. The "M' i»Uth .-c i„:j • . J . . """ *'""' wipers on me revolvmg shaft c. The 'he turnhrad ; 'tL^^rl. ^-^ '**' ff""'" ''''^'' of the feet, and the%urved form of abunSin? stl»m n? ^l '' T'^*^ *"^ ^""^^"^"y ^"™«J- ^t the same time, an ^rtu*nLad ^/.h c^^'^L ''"'*^^' ^"J*^« ^^^^^ throughout holes in the upper part ot ^untrv thev kr^Tft ?' ^'l ?^"*=^ "'^^ ^'^ Scotland and in Ireland. In the latter aTwrou.M ^^.h r T^^ ^*th double feet, suspended above and below two turnheads, frl^Ttf^^ort'^^eTpt^n'^^^^^ '' "^^"^- ^-'-^-k«> P-P-ly constructed, mak^ KivTn to wt.^f^71'n'"/ /' now entirely given up in Lancashire, where a preference is Ks?de of whfrh il!? tt'^^'^l' *"^ squeezers. The dash are small water-wheel^ inUrhtmUme'^^^^^^^^ eTo^"^"^^' '^^ ''''''' "^' ^^^^^'^^^ '^' ^ ^^ 196 BLEACHING. There are, besides, smaller openings for the free admission and egress of the water em- ployed in cleansing. The cloth, by the motion of the wheel, is raised up in one part of 141 MM?^ . IL Q I li the revolution of the wheel ; while, by its own weight, it falls in another. This kind oT motion IS very effectual in washing the cloth, while, at the same time, it does not injure Its strength. The plan, however, where economy of water is of anv importance, is very objectionable ; because the wheel must move at by far too great a Velocity to act to ad- vantage as a water-wheel. The wash or dash-wheel, now driven by power in all good bleach and print- works, is represented in fig. 142, upon the left side in a back view, and upon the ri«»ht side in a front vipw (the sketch being halved). Fig, HZ is a ground plan. a a is the washing- wheel ; b b its shaA-ends ; c c their brass bearings or plummer- blocks, supported upon the iron pillars d d. The frame is made of strong beams of wood, e e, bound together by cross bars with mortises. / /y two of the circular apertures, each leading to a quadrantal compartment within the dash-wheel. In the back view (the left-hand half of the figure) the brass grating g g, of a curvilinear fonn, is seen, through which the jets of water are admitted into the cavity of the ■ ■ , , . wheel; h hy are the round |C|3 U orifices, through which the foul water runs off, as each quadrant passes the lower part of its revolution ; t, a water-pipe, with a stop-cock for regulating the washing- jets ; k ky the lever for throw- ing the driving-crab /, or coupling-box, into or out of gear with the shaft of the wheel. This machine is so constructed, that the water- cock is opened or shut by the same leverage which throws the wheel into or out of gear, wi, a wheel, -, ./vi-vji-ti ^. ^^^ "PO" *^^ round ex- tremity of the shaft of the dash-wheel, which works into the toothed pinion connected » f I k BLEACHING. 197 with the prime mover. When the end of the lever fe, whose fork embraces the coupling- box upon the square part of the shaft, is pushed forwards or backwards, it shifts the clutch into or out of gear with the toothed wheel m. In the latter case, this wheel turns with its pinion without affecting the dash-wheel, n n, holdfasts fixed upon the wooden frame, to which the boards o o are attached, for preventing the water from being thrown about by the centrifugal force. The dash-wheel is generally from 6 to 7 feet in diameter, about 30 inches wide, and re- quires the power of about two horses to drive it. From one to two pieces of calico may be done at once in each quadrantal compartment, in the course of 8 or 10 minutes ; hence, in a day of 13 hours, with two such wheels 1200 pieces of yard-wide goods may be washed. After the process of washing by the dash-wheel, the water is expressed from the dotk by means of the squeezers already described. Bleaching of Linen. — Linen contains much more coloring matter than cotton. The former loses nearly a third of its weight, while the latter loses not more than a twentieth. The fibres of flax possess, in the natural condition, a light gray, yellow, or blond color. By the operation of rotting, or, as it is commonly called, water-retting, which is employed to enable the textQe filaments to be separated from the boon, or woody matter, the color becomes darker, and, in consequence probably of the putrefaction of the green matter of the bark, the coloring substance appears. Hence, flax prepared without rotting is much paler, and its coloring matter may be in a great measure removed by washing with soap, leaving the filaments nearly white. Mr. James Lee obtained a patent in 1812, as having discovered that the process of steeping and dew-retting is unnecessary, and that flax and hemp will not only dress, but will produce an equal if not greater quantity of more durable fibre, when cleaned in the dry way. Mr. Lee stated that, when hemp or flax plants are ripe, the farmer has nothing more to do than to pull, spread, and dry them m the sun, and then to break them by proper machinery. This promising im- provement has apparently come to naught, having been many years abandoned by the patentee himself, though he was favored with a special act of parliament, which permit- ted the specification of his patent to remain sealed up for seven years, contrary to the general practice in such cases. The substance which gives steeped flax its peculiar tint is insoluble in boiling water, m acids, and m alkalis ; but it possesses the property of dissolving in caustic or carbonated alkalme leys, when it has possessed the means of dehydrogenati'on by previous exposure to oxygen. Hemp is, in this respect, analogous to flax. The bleaching of both depends upon this action of oxygen, and upon the removal of the acidified dye, by means of an alkali. This process is effected generally by the influence of air in combination with light and moisture acting on the linen cloth laid upon the grass : but chlorine will effect the same object more expeditiously. In no case, however, is it possible to acidify the color completely at once, but there must be many alternate exposures to oxygen or chlo- rine, and alkali, before the flax becomes white. It is this circumstance alone which ren- ders the bleaching of linen an apparently complicated business. Having made ihese preliminary observations with regard to the method of applying the alkalme leys used in bleaching linen cloth, I shall now bring the whole into one point of view, by detailing the connexion of these processes, as carried on at a bleach-field, which has uniformly been successful in returning the cloth of a good white, and has otherwise given ^tisfaction to its employers ; and I shall only remark, that I by no means hold it up as the best process which may be employed, as every experienced bleacher knows that processes must be varied, not only according to existing circumstances, but also according to the nature of the linens operated upon. In order to avoid repetition, where washing is mentioned, it must always be under- stood that the hnen is taken to the wash-stocks or dash-wheel, and washed weU in them for some hours. This part of the work can never be overdone; and on its being properly executed between every part of the bucking, boilin?, steeping in the chloride of lime solution, and souring, not a little of the success of bleaching depends. By exposure is meant, that the linen cloth is taken and spread upon the bleach-ffreen for tour, six, or eight days, according as the routine of business calls for the returnV the cloth, in order to undergo further operations. A parcel of goods consists of 360 pieces of those linens which are called Britannias. li.ach piece is 35 yards long ; and they weigh, on an average, 10 lbs. each : the weight of parcel is, in consequence, about 3600 lbs. avoirdupois weight. The linens are first washed, and then steeped in waste alkaline ley, as formerly described under these pro- cesses; they then undergo the following operations :— 1st, Bucked with 60 lbs. pearl-ashes, washed, exposed on the field. 2d, Ditto 80 ditto ditto ditto ditto. 3d, Ditto 90 potashes ditto ditto ditto. 4th, Ditto 80 ditto ditto ditto ditto. 198 BLEACHING. BLEACHING. 199 If" \l m 5th, Bucked with 80 lbs. pearl-ashes, washed, exposed on the field. 6th, Ditto 50 ditto ditto ditto ditto. 7th, Ditto 70 ditto ditto ditto ditto. 8th, Ditto 70 ditto ditto ditto ditto. 9th, Soured one night in dilute sulphuric acid, washed. lOlh, Bucked with 50 lbs. pearl-ashes, washed, exposed on the field. 11th, Immersed in the chloride of potash or lime 12 hours. 12th, Boiled with 30 lbs. pearl-ashes, washed, exposed on the field, 13th, Ditto 30 ditto ditto ditto ditto. 14th, Soured, washed. The linens are then taken to the rubbing-board, and well rubbed with a strong lather of black soap, after which they are well washed in pure spring water. At this period they are carefully examined, and those which are fully bleached are laid aside to be blued, and made up for the market; while those which are not fully white are returned to be boiled, and steeped in the chloride of lime or potash ; then soured, until iher are fully white. By the above process, 690 lbs. weight of alkali is taken to bleach 360 pieces of linen, each piece consistmg of 35 yards in length; so that the expenditure of alkali would be somewhat less than 2 lbs. for each piece, were it not that some parts of the linens are not fully whitened, as above noted. Two pounds of alkali may therefore be staled as the average quantity employed for bleaching each piece of goods. The method of bleaching linens in Ireland is'similar to the foregoing ; any alteration in the process depending upon the judgment of the bleacher in increasrag or diminishing the quantity of alkali used. But it is common, at most bleach-fields, to steep the linens in the chloride of lime or potash at an early stage of the process, or after the goods have under- gone the fifth or sixth operation of bucking. By this means those parts of the flax which are most difficult to bleach are more easily acted upon by the alkali ; and, as before noticed, souring early in very dilute sulphuric acid, assists greatly in forwarding the whitening of the linens. Mr. Grimshaw, calico-printer, near Belfast, was the first who recommended early souring, which has since been very generally adopted. The bleaching of Silk— Silk in its raw state, as spun by the worm, is either white or yellow of various shades, and is covered with a varnish, which gives it stiffness and a degree of elasticity. For the greater number of purposes to which silk is applied, it must be deprived of this native covering, which was long considered to be a sort of gum. The operation by which this coloring matter is removed is called scouring, cleansing, or boiling. A great many different processes have been proposed for freein? the silk fibres from all foreign impurities, and for giving it the utmost whiteness, lustre, and pliancy; but none of the new plans has superseded, with any advantage, the one prac- tised of old, which consists essentially in steeping the silk in a warm solution of soap; a circumstance placed beyond all doubt by the interesting experiments of M. Roard. The alkalis, or alkaline salts, act in a marked manner upon the varnish of silk, and eflfect its complete solution ; the prolonged agency of boilinsr water, alone answers the same purpose ; but nothing agrees so well with the nature of silk, and preserves its brilliancy and suppleness so perfectly, as a rapid boil with soap-water. It would appear, however, that the Chinese do not employ this method, but something that is preferable. Probably the superior beauty of their white silk may be owing to the superiority of the raw ma- terial. The most ancient method of scouring silk consists of three operations. For the first, or theungumming, thirty per cent, of soap is first of all dissolved in clean river water by a boilmg heat ; then the temperature is lowered by the addition of a little cold water, by withdrawmg the fire, or at least by damping it. The hanks of silk, suspended upon horizontal poles over the boiler, are now plunged into the soapy solution, kept at a heat somewhat under ebullition, which is an essential point; for if hotter, the soap would attack the substance of the silk, and not only dissolve a portion of it, but deprive the whole of its lustre. The portions of the hanks plunged in the bath get scoured by degrees ; the varnish and the coloring matter come away, and the silk assumes its proper whiteness and pliancy. Whenever this point is attained, the hanks are turned round upon the poles, so that the portion formerly in the air may be also subjected to the bath. As soon as the whole is completely ungummed, they are taken out, wrung by the peg, and shaken out ; after which, the next step, called the boily is commenced. Into bags of coarse canvass, called pockets, about 25 lbs. or 35 lbs. of ungummed silk are enclosed, and put into a similar bath with the preceding, but with a smaller proportion of soap, which mar therefore be raised to the boihng point without any danger of destroying the silk. The ebullition is to be kept up for an hour and a half, during which time the bags must be frequently stirred, lest those near the bottom should suffer an undue degree of heat. The silk experiences in these two operations a loss of about 25 per cent, of its weight. The third and last scouring operation is intended to give the silk a slight tingej which renders the white more agreeable, and better adapted to its various nses in trade. la this way we distinguish the China white, which has a faint cast of red, the silver white, the azure white, and the thread white. To produce these diflferent shades, we begin by preparing a soap-water so strong as to lather by agitation ; we then add to it, for the China white, a little annotto, mixing it carefully in ; and then passing the silk properly- through it, till it has acquired the wished for tint. As to the other shades, we need only azure them more or less with a fine indigo, which has been previously washed severid times in hot water, and reduced to powder in a mortar. It is then difl"used through boiling water, allowed to settle for a few minutes, and the supernatant liquid, which contains only the finer particles, is added to the soap bath in such proportion as may be requisite. The silk, on being taken out of this bath, must be wrung well, and stretched upon perches to dry ; after which it is introduced into the sulphuring chamber, if it is to be made use of in the white state. At Lyons, however, no soap is employed at the third operation : after the boU, the silk is washed, sulphured, and azured, by passing through veiy clear river water properly blued. The silks intended for the manufacture of blonds and gauzes are not subjected to the ordinary scouring process, because it is essential, in these cases, for them to preserve their natural stiffness. We must therefore select the raw silk of China, or the whitest raw silks of other countries ; steep them, rinse them in a bath of pure water, or ia one con- taining a little soap ; wring them, expose them to the vapor of sulphur, and then pass them through the azure water. Sometimes this process is repeated. Before the memoir of M. Roard appeared, extremely vague ideas were entertained about the composition of the native varnish of silk. He has shown that this substance, so far from being of a gummy nature, as had been believed, may be rather compared to bees' wax, with a species of oil, and a coloring matter, which exists only in raw silks. It is contained in them to the amount of from 23 to 24 per cent., and forms the portion of weight which is lost in the ungumming. It possesses, however, some of the properties of vegetable gums, though it differs essentially as to others. In a dry mass, it is friable and has a vitreous fracture; it is soluble in water, and affords a solution which lathers like soap; but when thrown upon burning coals, it does not soften like gum, but bums with the exhalation of a fetid odor. Its solution, when left exposed to the open air, at first of a golden yellow, becomes soon greenish, and ere long putrefies, as a solution of animal matter would do 'n similar circumstances. M. Roard assures us that the city of Lyons alone could furnish several thousand quintals of this substance per annum, were it applicable to any useful purpose. The yellow varnish is of a resinous nature, altogether insoluble in water, very soluble in alcohol, and contains a little volatile oil, which gives it a rank smell. The color of this resin is easily dissipated, either by exposure to the sun or by the action of chlorine : it forms about one fifty-fifth of its weight. Bees' wax exists also in all the sorts of sUk, even in that of China ; but the whiter the filaments, the less wax do they contain. M. Roard has observed that, if the silk be exposed to the soap baths for some time after it has been stripped of its foreign matters, it begins to lose body, and has its valuable qualities impaired. It becomes dull, stiff, and colored in consequence of the solution more or less considerable of its substance ; a solution which takes place in all liquids, and even in boiling water. It is for this reason that silks cannot be alumed with heat ; and that they lose some of their lustre in being dyed brown, a color which requires a boiling hot bath. The best mode, therefore, of avoiding these inconveniences, is to boil the silks in the soap- bath no longer than is absolutely necessary for the scouring process, and to expose them in the various dyeing operations to as moderate temperature as may be requisite to communicate the color. When silks are to be dyed, much less soap shoulc* be used in the cleansing, and very little for the dark colors. According to M. Roard, raw silks, white or yellow, may be completely scoured in one hour, with 15 lbs. of water for one of silk, and a suitable proportion of soap. The soap and the silk should be put into the bath half an hour before its ebullition, and the latter should be turned about frequently. The dull silks, in which the varnish has already undergone some al- teration, never acquire a fine white until they are exposed to sulphureous acid gas. Ex- posure to light has also a very good effect in whitening silks, and is had recourse to, it b said, with advantage by the Chinese. Carbonate of soda has been proposed to be used instead of soap in scouring silk, but it has never come into use. The Abbe Collomb, in 1785, scoured silk by eight hours- boiling in simple water, and he found the silks bleached in this way to be stronger than by soap, but they are not nearly so white. A patent has been taken out in England for bleaching them by steam, of which an account will be found under the article Silk. It appears that the Chinese do not use soap in producing those fine white sUks which are imported into Europe. Michel de Grubbens, who resided long at Canton, saw and 200 BLEACHING. BLEACHING OP PAPER. 201 |4 . Il u ■ U f ^t:\ f: } I ^ctise-l himself .the operation there, which he published in the Memoirs of th«. Academy of Stockholm in 1803. It consists in preparing the silk wiT a species of White beans, smaUer than the Turkey beans, with some wheat flour, common S^lt and form this vegetable bath. The beans must be previously washed. It is difficult to dis- cover what chemical action can occur between that decoction and the varnish of raw Silk ; possibly some acid may be developed, which may soften the gummy matter and facilitate Its separation. s"^^^j^ mauer, ana Baume contrived a process which does not appear to have received the sanction of experience, but which may put us in the right way. He macerates the yellow raw silk ln-5 °^?.7 ^J'^rr ";' ^ •\^'?- ^'' ^.^^^^ ^^^ «°^ thirty-second part of pure muriaUc ^ ?• i rf i f^'^y:flS^^^ouTs, It is as white as possible, and the more so, the better the quality of the silk. The loss which it sufl^ers in this menstruum is only one fortieth ; showmg that nothing but the coloring matter is abstracted. The expense of Uus menstruum is the great obstacle to Baume's process. The alcohol, however! might dTstiUatron!""^ ^''^' ""^^'""^ recovered, by saturating the acid with chalk, and fe- .„ifir'^'"^y W-oo/.-Wool like the preceding fibrous matter, is covered with a pe- cuhar varnish which impairs its qualities, and prevents it from being employed in 5^ raw state for the purposes to which it is weU adapted when it is scoured. The English give the name yoZfc and the French suint, to that native coat : it is a fatty unctuous mat if 'thlth ""^T'^^^^'v' apparently has its chief origin in the cutaneous perspiLTon of the sheep; but which, by the agency of external bodies, may have undergone ^me ^n tf/t 7h ' J-'^^ ''' constitution. It results from the 'experiments of M^ Vau^^e! Ijn, that the 2/o/fe is composed of several substances; namely, 1, a soap with basis of n^ a^h' "". n? """"''T'' ?•' ^T'^^ P"^^ «^ ''-^ 2, of a notable quantityI?acSe of ^L:~s:L::lTei;:'^^^^ ^^^^-^^ '-- ^^-L several otheT^ccS The proportion of yolk is variable in diflerent kinds of wool, but in general it is more The yolk, on account of its soapy nature, dissolves readily in water with tbp pt ception of a little free fatty matter, which easily separates fJom tie fikments andrl' mams floating m the liquor. It would thence appear sufficient to expo^'heVo^fs ^ simple washing in a stream of water; yet experience shows that this method nrvTr an- swers so well as that usually adopted, which consists in steeping the woo fS some time n simple warm water, or in warm water mixed with a fourth of stale urine' From"? LLTk'' 't '"'T':- ^'' '"i?"'^"* ^" '^'' '^''> i^ ^^ ^^^' the bath as warm as tie hand can bear it and stir it well with a rod. At the end of this time the wool may be Ittrear^/wat'er ' ' '" "^''"^ ^" ^"^^^ ^'^'''' ^^ ""'^'^ '^ ^« '^^^'^'^'y ^-"'d m It is generally supposed that putrid urine acts on the wool by the ammonia which it Z^CT: ^"t^ V^^' t''^;"^'' !^ ^^P^^^^y '^^ ^^"^^"^^^ «^ ^he fatty matter not cTmbted with the potash M. Vauquclin is not of this opinion, because he found that wool sTeen^ ZZ T: ^'!\'^^- V^'^'^''^^ «"d quick lime, is not better scoured than an«i3quant^!v nfitTrfilr'-'^ ""-^l"!!'' ^^T'. ^' ^^« ^^"^« ^^ t« ^°"^1»J« that the gTd effect" of t^l^l ,1. ""T T^^- ^ ^'"'^^ to anything else besides the ammonia, and probab y to the urea. Fresh urine contains a free acid, which, by decomposing the pot^h Zal of the yolk, counteracts the scouring operation. * lue poiasn soap ol If wools are better scoured in a small quantity of water than in a great stream wp can conceive that ths circumstance must depend upon the nature of the ydkfXh Tn a concentrated solution, acts like a saponaceous compound, and thus conStls to re ^Zon"^nZ\"''\^^''''' r'l'^ ^^'^^^ ^« '^' ^'^^^^ts! It should ds^ be observ^ that too long a continuance of the wool in the yolk water, hurts its quality very m7ch by weakening its cohesion, causing the filaments to swell, and even to split! It i^said then to have lost its r^m. Another circumstance in the scouring of woo that 'hou d ^ways be attended to, is never to work the filaments together to such a deg ee as toT- ^.11 l^Z ^1k""' ^"V" «?itatingwe must merely push them slowlv round in the nS spin wX ^'^ ^ "' '^' ^""'- ^^^'^ '' ^' ^ ^^^^^^' ^t would neither card As the heat of boiling water is apt to decomiwse woollen fibres, we should be careful ^' u'ooT' '^ ^«"Pf5^t"^^ «f the scouring bath to near this point, nor, in fact, Tex eeed 140^ F. Some authors recommend the use of alkaline or Lap; baths for scourfna wl 'i^'^^^'^T- P^*?P^^ **° r^ ^^^^^te from the method above described. ^ Wiicn the washing is completed, all the wool which is to be sent white into the mar- ket, must be exposed to the action of sulphurous acid, either in a liquid or a gaseous state. In the latter case, sulphur is burned in a close chamber, i» which the wools are hung up or spread out; in the former, the wools are plunged into water, moderately impregnated with the acid. (See Sulphuring.) Exposure on the grass may also con- tribute to the bleaching of wool. Some fraudulent dealers are accused of dipping wools in butter-milk, or chalk and water, in order to whiten them and increase their weight. Wool is sometimes whitened in the fleece, and sometimes in the state of yarn ; the latter affording the best means of operating. It has been observed that the wool cut from certain parts of the sheep, especially from the groins, never bleaches well. After sulphuring, the wool has a harsh crispy feel, which may be removed by a weak soap bath. To this also the wool comber has recourse when he wishes to cleanse and whiten his wools to the utmost. He generally uses a soft or potash soap, and after the wool is well soaked in the warm soap bath, with gentle pressure he wrings it well with the help of a hook, fixed at the end of his washing tub, and hangs it up to dry. Bleaching of raga, and paste for paper making. — After the rags are reduced to what is called half stuff", they should have the greater part of the floating water run off", leaving just enough to form a stir-about mass. Into this a clear solution of chloride of lime should be poured, of such a strength as is suited to the color of the rags, which should have been previously sorted; and the engine is kept going so as to churn the rags with the bleaching agent. After an hour, the water may be returned upon the engine, and the washing of the paper resumed. From two to four pounds of good chloride of lime are reckoned sufficient to bleach one hundred weight of rags. When the rags consist of dyed or printed cottons, after being well washed and re- duced to half stuff, they should be put into a large cask or butt, supported horizontally by iron axles upon cradle bearings, so that it may be made to revolve like a barrel- churn. For each hundred weight of the colored rags, take a solution containing from four to eight pounds of chloride of lime ; add it to the liquid mixture in the butt along with half a pound of sulphuric acid for every pound of the chloride ; and after inserting the bung, or rather the square valve, set the vessel in slow revolution backwards and for- wards. In a short time the rags will be colorless. The rags and paper paste ought to be very well washed, to expel all the chlorine, and perhaps a little muriatic acid might be used with advantage to dissolve out all the calcareous matter, a portion of which is apt to remain in the paper, and to operate injuriously upon both the pens and the ink. Some of the French paper manufacturers bleach the paste with chlorine gas. Paper prepare! from such paste, well washed, is not apt to give a brown tint to maps, as that carelfsslv bleached with chloride of lime is known to do. . .■, , .j /• BLEACHING OF PAPER. The following are the proportions of Uqmd chlonde of lime, at 10° of Gay Lussac's Chloromctre, employed for the different sorts of rags, con- sisting of two piles, or 200 poundl French. Cotton. No. 1. 2. 3. 4. 6. 6. Fine cotton rags Clean calicoes White dirty calico, coarse cotton Coarse cotton Grey, No. 1 - No. 2 - Saxon gray No. 2 Pale white and half-white shades Saxon blues ; pale pink, dark blue, velvet - litres. 10 12 14 16 18 20 22 24 26 28 32 It is considered to be much better to bleach the fine rags with liquid chloride of lime, and not with chlorine gas, because they are less injured by the former, and afford a paper of more nerve, less apt to break, and more easily sized. But the coarse or gray rags are much more economically bleached with the gaseous chlorine, without any risk of weakening the fibre too much. Bleaching by the gas is performed always upon the sorted rags, which have been boiled in an alkaline ley, and torn into the fibrous state. They are subjected to the press, in order to form them into damp cakes, which are bro- ken in pieces and placed in large rectangular wooden cisterns. The chlorine gas is in- troduced by labes in the lid of the cistern, which falls down by its superior gravity, acting always more strongly upon the ra rs at the bottom than those above. When the chlorine, disengaged from 150 kilogrammes (330 lbs.) of manganese and 500 kilos, of muriatic acid, is made to act upon 2,500 kilos, of the stuff (supposed dry), it will have completed its effect in the course of a few hours. Thequanlity of gaseous chlorine is equal to what is contained in the quantity of chloride of lime requisite to pro- duce a like bleaching result. The bleached stuff should be forthwith carefully washed. n n it * »-:! 202 BLOCK MANUFACTURE. to remove all the muriatic acid produced from the chlorine ; for if any of this remain in the paper, it destwys lithographic stones and weakens ooramon ink. BLENDE. (Fr. and Germ.) Sulphuret of zinc, so named from the German blendeii, to dazzle, on account of its glistening aspect. It is called black jack from its usual color. Its lustre is pearly adamantine. Spec, gravity from 3*7 to 4*2. It contains frequently iron, copper, arsenic, cadmium and silver, all associated with sulphur. It is worked up partly into metallic zinc, and partly into the sulphate of zinc, or white vitriol It consists of 66 "7 2 zinc, and 33 "28 sulphur ; being nearly by weight as two to one. See Zinc. BLOCK MANUFACTURE. Though the making of ships' blocks belongs rather to a dictionary of engineering than of manufactures, it may be expected that I should give some account of the automatic machinery for making blocks, so admirably devised and mounted by M. L Brunei Esq., for the British navy, in the dockyard of Portsmouth. The series of machines and operations are as follows : — 1. 77ie straight cross cutting saw. — The log is placed horizontally on a very low bench, which is continued through the window of the mill into the yard. The saw is exactly over the place where the log is to be divided. It is let down, and suffered to rest with its teeth upon the log, the back still being in the cleft of the guide. The crank being set in motion, the saw reciprocates backwards and forwards with exactly the same motion as if worked by a carpenter, and quickly cuts through the tree. When it first begins to cut^ its back is in the cleft in the guide, and this causes it to move in a straight line; but before it gets out of the guide, it is so deep in the wood as to guide itself ; for in cutting across the grain of the wood, it has no tendency to be diverted from its true line by the irregular grain. When the saw has descended through the tree, its handle is caught in a fixed stop, to prevent its cutting the bench. The machine is thrown out of gear, the attendant lifts up the saw by a rope, removes the block cut off, and advances the tree to receive a fresh cut. 2. The circular cross cutting saw. — ^This saw possesses universal motion ; but the axis is always parallel to itself, and the saw in the same plane- It can be readily raised or lowered, by inclining the upper frame on its axis ; and to move it sidewise, the saw frame must swing sidewise on its joints, which connect it with the upper frame. These movements are effected by two winches, each furnished with a pair of equal pinions, working a pair of racks fixed upon two long poles. The spindles of these winches are fixed in two vertical posts, which support the axis of the upper frame. One of these pairs of poles is jointed to the extreme end of the upper frame ; therefore by turning the han- dle belonging to them, the frame and saw is elevated or depressed ; in like manner, the other pair is attached to the lower part of the saw frame, so that the saw can be moved sidewise by means of their handles, which then swing the saw from its vertical position. These two handles give the attendant a complete command of the saw, which we suppose to be in rapid motion, the tree being brought forward and properly fixed. By one handle, he draws the saw against one side of the tree, which is thus cut into (per- haps half through); now, by the other handle, he raises the saw up, and by the first- mentioned handle he draws it across the top of the tree, and cuts it half through from the upper side ; he then depresses the saw and cuts half through from the next side ; and lastly a trifling cut of the saw, at the lower side, completely divides the tree, which is then advanced to take another cut. The great reciprocating saw is on the same principle as the saw mill in common use in America. 3. The circular ripping saw is a thin circular plata of steel, with teeth similar to those of a pit saw, formed in its periphery. It is fixed to a spindle placed horizontally, at a small distance beneath the surface of a bench or table, so that the saw projects through a crevice a few inches above the bench. The spindle being supported in proper collars, has a rapid rotatory motion communicated to it by a pulley on the opposite end, round which an endless strap is passed from a drum placed overhead in the mill. The block cut by the preceding machine from the end of the tree, is placed with one of the sides flat upon the bench, and thus slides forward against the revolving saw which cuts the wood with a rapidity incredible to any one who has not seen these or similar machines. 4. Boring machine.— The blocks, prepared by the foregoing saws, are placed in the machine represented in^^. 144. This machine has an iron frame, a a, with three legs, beneath which the block is introduced, and the screw near b being forced down upon it, confines it precisely in the proper spot to receive the borers d and e. This spot is de- termined by a piece of metal fixed perpendicularly just beneath the point of the borer e, shown separately on the ground at x ; this piece of metal adjusts the position for the borer d, and its height is regulated by resting on the head of the screw x. which fastens the piece x down to the frame. The sides of the block are kept in a parallel position, by being applied against the heads of three screws tapped into the double leg of the frame A. The borer d is adapted to bore the hole for the centre pin in a direction exactly per- BLOCK MANUFACTURE. 203 pendicular to the surface re^^^^^l^^^^^^ ^S^^rtl^I^^col^^^^^^^^ holes for the commencement of t^^/^^^^^^./^''^^, ^ l^^n mandrels, mounted in frames the same manner ; they ««• V*^"^^^^-! ^T^^^^StS wTh sUders upin the angular edges Bimilar to a lathe. These frames g ^J^^ "'"^. XVeTs screwed fast to the frame; the of the flat broad bars, i and k The ^^^^^ «/^^^^fjf^ '.'.^^^^^ at L l, beneath the Utter is fixed upon a frame of its «-^>.fJ ^"^V.'ifb^^^^^^^^^^^^ within certain principal frame of the °ia<^^.'"^:.«.^y„7''TrnV These limits are determined by two limits so as to bore holes '^ ^^'^^Z'^'''Zn mandrel and its frame being ing a circular saw . »<»» 'J' ^'^ jMit '«ot -quir^^^^^^ exactly similar to those at G »°^ "'j^f- '7/ °°7 " ^Agj ^, This frame is screwed ll"2^f ^e tmT.' rpV^^^^^^^^^ ^- l-Z^^X^:'^^:^-'^^^^ end Uept up' .0 its ^iUo. by the other part of the bench d p. ^^ ^^^^ ^ff jj. By sUding the block along this bench, it ^» *Pf f Vr .he sh^Mn- engine. All the angles, as is evident from the figure, and prepares t ^^J^lJ^ f X%o ?he trough, or four ^gles are cut off in succession, by applying its dfere^t sides « i g ,^ eUlent If la^ng ptct of w^ o? different thickness against the plane . i>, so as to y - m »m*'1U>- I 20i BLOCK MANUFACTURE. BLOCK MANUFACTURE. 205 from large than from smaU blocks. The Sken [o '° '^' ''"'" °^ *= ^« »«^ ^J; ??u *^^^"«^ 7Wfff;i/7,e.-_A great deal of the apparent complication of this %ure arises from the iron cage, which IS provided to defend the workmen, lest the blocks, which are revolving in the circles, or chuck, with an Lmense velocity, should be loosened by the ac tion of the tool, and fly out by their centrifugal force. Without this provi- sion, the consequences of such an acci- dent would be dreadful, as the blocks would be projected in all directions, with an inconceivable force. 8. The scoring engine receives two blocks, as they come from the shaping engine, and forms the groove round their longest diameters for the reception of their ropes or straps, as represented m the two snatch blocks and double block, under /g,. 144, 145. A, B, Jig. 146, represent the above two blocks, each held between twosmal' pillars a (the other piUar is hid behind the block), fixed in a strong plate d, and pressed against the pillars by a screw L _ which acts on a clamp d. Over the tcrs, E E, are situated, both being fixed on the ^Jnl.- *P^'\o^ circular planes or cat- m the middle of it. The spinJle is fiUed inTfrn^"''^^^' "^^'"-^ '' ^"^^^ ^^ » P»"ey as to rise and fall when moved by a handle f Th^hZI: f^""^ ^" "^"^^« ^' ' ^^ ^ blocks ; and the depth to which they can cuUs rl^ulat^ £ « ' '"'^'"1 *^°^" "P«" ^^« screws upon the plate d, between the block. Tin! .k^ ^ * ''''^^^ ^^^P^ g» filed by ft, fixed to the frame f, and enclos n" b^n^f t T- *^'\'''^' * '^"'^^^^ P'^^e of mettU ters to traverse the whole length o^rheblocLth^^^^^^^^^ the pulley To admit the cuU It) is sustained between the points of two cent; J^ ^ir J" ^°' '^^^'' ^ ^^"^« beneath tres. The frame inclines when the } aire L^^.r. 7' f^ ''^" ^^ ^> «» ^hese cen- at the end of it, counterbalancing the wei'h oPthe'bLk^' ""i' ^1 ^''''* ^^^^ ^ ^'^^^'^ above the centre on which they mSve. Sframe l ^ «!.« ' ^"1 ^^^^ ?' ^" ^^^^^ ^^e to balance the cutters, &c. The cutters rp«^n '" f^° Pl^^l^ed with a counterpoise edges. Each has two Notches in its circTrnferercp ^ 1 "•,^^'!^' ^^ ^'^''^ ^'^»» ^°»«d chisels are fixed by screws, to prc^Lc bev^^^^^^ ''^'V ?"d in these notches plane iron before its face. '^ ^ "^"^ ""^ '^^ ^^^e^* ^^ the manner of a such a segment of each as wMl in<,t t^^ T'l, ?' "'"/"'' ™' '"'»y> '«»»«? only taken out to admit the cuttrio olra.e h«if ^^1^' *"■* ""* "^"^ ""•'«» «he- « blocks into this machine the woX^^ between them, or nearly so. In putting the daws ofthe clamps, but tak«r«?rha?,Kri'''^ ''?V'''^ PriWs to the ends of he they should be: he then takel thTha„l ^ and hvT '■'^''" '«^'*«<^» ">« P'"» « than we suppose are slandinj siai) do^Z,n\Zu I T'" ^^ '=""^" = *: ("'Wch pins at the same time, till the desX of^Jhe l.^^?' ''^P'««!"S them between their on the shape g. He now tumsTe s«ew^ 6 6 .rfii' ,T^?f ."'' '•'"' P'^« * '<'^«''? being pat in motion cut the scores, Vh"h will be ll„ v . "'k' ',^''"- ^he cuttera »a:c2srrb!:cti,lrkt^r.ht^^^^^^ handle/, they wiU cut an'y depth '^^^'^^111,^71:^.^:^^^^^/'^^^^ By this means one quarter of the scorp i« fm-mo/i ♦!. .1. blocks together half l„d in this m^nr iZf.l^^%TJ ^Z K-JK i* itself, but into a frame seen at r beneath the plate, which is connected with it by a cenS-e pin, exactly midway between the two blocks A b. A spring catch, the end of S is s^en at r, confines them together ; when this catch is pressed back the plate d Tan be turned aboit upon its centre pin, so as to change the blocks, end for end and bring the unscored qukrters (». e. over the clamps) beneath the cutters; the workman S- the handles / and l, one in each hand, and pressing them down, cute out the ^ind quarter This might have been eflected by simply lifting up the handle l ; bu in that^se the cutter would have struck against the grain of the wood so as to cut mier rou-hly : but by this ingenious device of reversmg the blocks, it always cuts de^ and sm(x,th, in the direction of the grain. The third and fourth quarters of the score are cut by turning the other sides of the blocks upwards, and repeating the above ooeration The shape g can be removed, and another put in its place, for diflerent sizes and curves of block; but the same pins a, and holding clamps d, wiU suit many different By these machines the shells of the blocks are completely formed, and they are next polished and finished by hand labor ; but as this is performed by tools and methods which are well known, it is needless to enter into any explanation : the finishing required bemg only a smoothing of the surfaces. The machines cut so perfectly true as to require no wood to be removed in the finishing ; but as they cut without regard to the irregularity of the grain, knots, &.c., it happens that many parts are not so smooth as might be wish- ed and for this purpose manual labor alone can be employed. The lignum vitae for the sheaves of the blocks, is cut across the grain of the wooc by two cross-cutting saws, a circular and straight saw, as before mentioned. These ma- chines do not essentially differ in their principle from the great cross-cutting saws we have described, except that the wood revolves while it is cutting, so that a small saw will reach the centre of a large tree, and at the same time cut it truly flat. The limiis pre- scribed for our plates will not admit of giving drawings of these machines, and the idea which could be derived from a verbal description would not be materially different from the cross-cutting saws before mentioned. These machines cut off their plates for the end of the tree, which are exactly the thickness for the intended sheave. These pieces are of an irregular figure, and must be rounded and centred in the crown saw. 9. The crovm saw is represented in fig. 147, where A is a pulley revolving by means of an endless strap. It has the crown or trepan saw a fixed to it, by a screw cut within the piece, upon which the saw is fixed, and which gives the ring or hoop of the saw sufficient stability to perform its oflice. Both the pulleys and saw revolve together upon a truly cylindrical tube 6, which is stationary, being attached by a flaunch c to a *^ - fixed puppet b, and on this tube as an ajiis the saw and pulley turn, and may be slid endwise by a collar fitted round the centre- piece of the pulley, and having two iron rods (only one of which can be seen at d in the figure), passing through holes made through the flaunch and puppet b. When the saw is drawn back upon its central tube, the end of the latter projects beyond the teeth of the saw. It is by means of this fixed ring or tube within the saw, that the piece of wood 6 is supported during the operation of sawing, being pressed forcibly against it by a screw d, acting through a puppet fixed to the frame of the machine. At the end of this screw is a cup or basin which applies itself to the piece of wood, so as to form a kind of vice, one side being the end of the fixed tube, the other the cup at the end of the screw d. Within the tube 6 is a collar for supporting a central axis, which is perfectly cylindrical. The other end of this axis, (seen at /,) turns in a collar of the fixed puppet e. The central axis has a pulley f, fixed on it, and giving it motion by a strap similar to the other. Close to the latter pulley a collar g is fitted on the centre piece of the pulley, so as to slip round freely, but at the same time confined to move endways with the pulley and its collar. This col- lar receives the ends of the two iron rods d. The opposite ends of these rods are, as above mentioned, connected by a similar collar, with the pulley A of the saw a. By this connexion, both the centre bit, which is screwed into the end of the central axis /, and the saw sliding upon the fixed tube 6, are brought forward to the wood at the same time, both being in rapid motion by their respective pulleys. 10. The Cooking Engine.— This, ingenious piece of machinery is used to cut the three 206 BLUE DYES. semicircular holes which surround the hole hored by the crown saw, so as to produce a cavity in the centre of the disc. f vc a 1 1. Face-turning Lathe— The sheave is fixed against a flat chuck at the end of a mandrel, by a universal chuck, similar to that in the coaking engine, except that the centre pm, instead of having a nut, is tapped into the flat chuck, and turned by a screw- driver. BLOOD. (Sang, Fr. ; Blut, Germ.) The liquid which circulates in the arteries and vems of animals ; bright red in the former and purple in the latter, among all the tribes whose temperature is considerably higher than that of the atmosphere. It consists, 1. of a colorless transparent soluUon of several substances in water; and, 2. of red, undissolved particles diffused through that solution. Its specific gravity varies with the nature and health of the animal ; being from 1-0527 to 1-0570 at 60° F. It has a saline sub-nauseous taste, and a smell peculiar to each animal. When fresh drawn from the vessels, it rapidly coagulates into a ge atinous mass, called the clot, cruor, or crassamentum, from which, after some time, a pale yellow fluid, passing into yeUowish green, oozes forth, called the *T*^L '^''™ ^^«°?> stirred with a bundle of twigs, as it flows from the veins, the fibnne concretes, and forms long fibres and knots, while it retains its usual appear- ance m other respects. The clot contains fibrine and coloring matter in various pro- portions. Berzelius found in 100 parts of the dried clot of blood, 35 parts of fibrine : 68 of coloring matter ; 1-3 of carbonate of soda ; 4 of an animal matter soluble in water, 1 ^! "^1*/°™^ f '^^ ^^^ ^^^' ^^^ ^P^*^^^<^ ^•^^•^y of the serum varies from 1-027 to 1-029 It forms about three fourths of the weight of the blood, has an alkaline leaction, coagulates at 16^ F. into a gelatinous mass, and has for its leading consutuent albumen to the amount of 8 per cent , besides fat, potash, soda, and salts of these bases. Blood uoes not seem to contain any gelatine. The red coloring matter called hemaline, may be obtained from the cruor by washing With cold water and filtering. ^ Blood was at one time largely employed for clarifying sirup, but it is very sparingly used by the sugar refiners in Great Britain of the present day. It may be dried by evapo- ration at a heat of 130° or 140°, and in this state has been transported to the colonies for puritying cane juice. It is an ingredient in certain adhesive cements, coarse pigments for protecting walls from the weather, for making animal charcoal in the Prussian blue works, and by an after process, a decoloring carbon. It is used in some Turkey red dye-works. Blood IS a powerful manure. j j i«. BLOWING MACHINE. See Iron, Metalluhgt, Ventilatiok. ^ BLOWPIPE. (Chalumeau, Fr. ; Lothrohn, Germ.) Jewellers, mineralogists, chero- isTs, enamellers, &c., make frequent use of a tube, usually bent near the end, terminated with a finely pointed nozzle, for blowing through the flame of a lamp, candle, or gas-jet, and producmg thereby a small conical flame possessing a very intense heat. Modifica- tions of blow pipes are made with jets of hydrogen, oxygen, or the two gases mixed in due proportions. BLUE DYES. {Tdnt, Germ. See Enamel.) The materials employed for this pur- pose are indigo, Prussian blue, logwood, bUberry, (vaccinium myrtillus,) elder berries, (sambucus nigra,) mulberries, privet berries, (ligustrum vulgare,) and some other berries whose juice becomes blue by the addition of a small portion of alkali, or of the salts of copper. For dyeing with the first three articles, see them in their alphabetical places. I shall here describe the other or minor blue dyes. ^ To dye blue with such berries as the above, we boil one pound of them in water, add- ing one ounce of alum, of copperas, and of blue vitriol, to the decoction, or in their stead equal parts of verdigris and tartar, and pass the stuflfs a suflScient lime through the liquor. When an iron mordant alone is employed, a steel blue tint is obtained; and when a tin one, a blue with a violet cast. The privet berries which have been employed as sap r ?r L- ^^'^^ painters, may be extensively used in the dyeing of silk. The berries liJ* Alrican night-shade (solanum guineetise) have been of late vears cor.siderably ap- plied to silk on the continent in producing various shades of blue, violet, red, brown, &c., but particulariy violet. With alkalis and acids these berries have the same habitudes as bilberries ; the former turning them green, the latter red. They usually come from Italy compressed in a dry cake, and are infused in hot water. The infusion is merely Wtered, and then employed without any mordant, for dyeing sUk, being kept at a warm temperature by surrounding the bath vessel with hot water. The goods must be winced for six hours through it in order to be saturated with color ; then they are to be rinsed in running water and dried. One pound of silk requires a pound and a half of the berry cake. In the residuary bath, other tints of blue may be given. Sometimes the dyed silk is finished by running it through a weak alum water. A color approaching to in- digo m permanence, but which differs from it in being soluble in alkalis, though inca- pable of similar disoxydizement, is the gardenia genipa and acuUata of South America whose colorless juice becomes dark blue with conUct of airj and dyes stuffs, the skin I BOILERS. 207 and nails of an unchangeable deep blue color, but the juice must be applied in the color- less state. See Indigo and Prussian Blue. . i i • ^^ BLUE PIGMENTS. Several metallic compounds possess a blue color; especially those of iron, cobalt, and molybdenum. Tlie metallic pigments, little if at all employed, but which may be found useful in particular cases, are the molybdate of mercury, the hydro-sulphuret of tungsten, the prussiate of tungsten, the molybdate of tin, the oxide of copper darkened with ammonia, the silicate of copper, and a fine violet color formed from manganese and molybdenum. The blues of vegetable origin, in common use, are in- digo, litmus, and blue cakes. The blue pigments of a metallic nature found in com- merce are the following ; Prusdan blue ; mountain blue, a carbonate of copper mixed with more or less earthy matter ; Bremen blue or verditer, a greenish blue color obtained from copper mixed with chalk or lime ; iron blue, phosphate of iron, little employed ; cobalt blue, a color obtained by calcining a salt of cobalt with alumina or oxide of tin; muilt, a glass colored with cobalt and ground to a fine powder; charcoal blue, a deep shade' obtained by triturating carbonized vine stalks with an equal weight of potash in a crucible till the mixture ceases to swell, th^m pouring it upon a slab, putting it into water, and saturating the alkali with sulphuric acid. The liquor becomes blue, and lets fall a dark blue precipitate, which becomes of a brilliant blue color when heated. Molybdenum blue is a combination of this metal, and oxide of tin, or phosphate of lime. It is emplo5'ed both as a paint, and an enamel color. A blue may also be ob- tained by putting into molybdic acid (made by digesting sulphuret of molybdenum with nitric acid) some filings of tin and a little muriatic acid. The tin deoxidizes the molybdic acid to a certain degree, and converts it into the molybdous, which, when evaporated and heated with alumina recently precipitated, forms this blue pig- ment Ultramarine is a beautiful blue pigment, which see. BLUE Turnbull's and Chinese are both double cyanides of iron. BLUE VITRIOL; sulphate of copper. BOILERS {construction of). — The modifications of the steam engine which hare been adopted since its introduction by Watt, three quarters of a century ago, have been very numerous and varied ; and although the progression in its applications and improve- ments has been most rapid and wonderful, we are still undecided as to the best form of its construction. Sound principles scientifically applied, and the gradually increasing ex- cellence of our mechanical workshops, have enabled us to attain the great perfection which characterizes the working parts of the modern steam engine. The steam engine itself may be regarded as a comparatively perfect machine, and therefore we shall confine our observations almost exclusively to that very important and necessary adjunct — the Boiler — which is the source of its power. With this limitation, a very wide field of in- quiry is opened out, and in the earliest steps of the investigation we become perplexed with the endless variety of forms and constructions which at different periods have been adopted by engineers, and which have never, unfortunately, received the same Judicious attention that was paid, as I have already remarked, to the steam engine. This is an ano- malous and much to be regretted fact, for the boiler, being the source of the motive pow- er, is undoubtedly one of the most important parts of the whole machine. Upon its proper proportions and arrangements for the generation of steam, depend the economy and regularity with which the engine can be worked, and upon its strength and excel- lence of workmanship depends the safety of the lives and property of those who come in contact with it. Regarding the steam engine as one of the most active agents in the extension of our prosperity, and in the civilization of the world, and seeing how it is mixed up with the daily duties and working of society, the safety and efficiency of every part, and more especially the boiler, are subjects of national importance ; and it is of great consequence to introduce here such knowledge and experience on this subject of deep interest as has been offered by William Fairbairn, Esq. "The boiler may be considered in its construction, management, security, and eco- nomy. 1st As to the construction. Here I shall have to go a little into detail, in order to show, in construction, the absolute necessity there exists for adhering to form and other considerations essential in the practice of mechanical engineers, so as to effect the maximum of strength, with the minimum of material. In boilers this is the more important as any increase in the thickness of the plates obstructs the transmis- sion of heat, and exposes the rivets as well as the plates to injury on the side exposed to the action of the furnace. " It has generally been supposed that the rolling of boiler plate iron gives to the sheets greater tenacity in the direction of their length than in that of their breadth ; this is, however, not correct ; as a series of experiments which Mr. Fairbairn made some years since fully proves that there is no difference in the tensile strength of boiler plates whether torn asunder in the direction of the fibre, or across it From five different sorts of iron the following results were obtained :— hr 208 Deecription of Iron. Yorkshire plates Yorkshire plates Derbyshire plates Shropshire plates Staffordshire plates Mean BOILERS. Mean Breaking weight In tons, in the direc- tion of the fibre. - 26-7'? - - 22-76 - - 21-68 - - 22-82 - - 19-66 - Mean Breaking weight in tons across th« fibre. 27-49 26-37 18-66 22-00 21-01 - 22-51 2310 100 70 56 "Assuming the strength of the plate to be ... fhp^Im^^'' ""^ a double riveted joint would be. after allowing for the adhesion of the surfaces of the plate - - ^ And the strength of a single riveted joint . . the direction of the greatest strain ; and in order to accomDlisfi fhi! ff ^mt ^ derived from experimental research. On this head I am forfntinfi^ Jn i!!l- ^i ?^ me thecalculations of Professor W. R. Johnson, of the F™aSn?i:tLeo^^^^^^^^^ whrch JryVr •"'" '''\''T^'^ -f cylindrical boilers are ogreft'aL and from which the following short abstract may be useful. ' "Ist To know the force which tends to burst a cvlindrical ves sure per unit of surface. The retaining oi* quiescent force, in the same direction, is only the strength or tenacity of the two opposite sides of the supposed bond. Here also, at the moment when a rupture is about to occur, the divellent force must exactly equal the quiescent force. *' Mr. Johnson then goes on to show that, as the diameter is increased, the product of the diameter, and the force or pressure per unit of surface, are increased in the same ratio. This truth I shall endeavor to prove ; as, also, that, as the diameter of any cylindrical vessel is increased, the thickness of the metal must also be increased in the exact ratio of the increase of the diameter: the pressure, or as Mr. Johnson calls it, the divellent force, being the same when the diameter of a boiler is increased, it must be borne in mind that the area of the ends is also increased, not in the ratio of tlie diameter but in the ratio of the square of the diameter : and it will be seen that instead of the force being doubled, as is the case in the direction of the diameter and circumference, it is quadrupled upon the ends, or, what is the same thing, a c^^inder double the dia- meter of another cylinder has to sustain four times the pressure in the longitudinal t direction. The retaining force of the thickness of the metal of a cylindrical boiler does not^ however, increase in the same ratio as the area of the circle, but simply in the ratio of the diameter ; consequently, the thickness of the metal will require to be in- creased in the same ratio as the diameter is increased. From this it appears, that the tendency to rupture by blowing out the ends of a cylindrical boiler will not be greater in this direction than it is in any other direction ; we may therefore safely conclude, since we have seen that the tendency to rupture increases in both directions in the ratio of the diameter, that any deviation from that law, as regards the thickness of the i)lates, would not increase the strength of the boiler. " I have been led to these inquiries from the circumstance that Mr. Johnson appears to reason on the supposition that there are no joints in the plates, and that the tena- city of the iron is equal to 60,000 lbs.— rather more than 26 tons to the square inch. Aow, we have shown by the results of the experiments already adduced, that ordinary boiler plates will not bear more than 23 tons to the square inch; and, as nearly one third ot the material is punched out for the reception of the rivets, we must still lurther reduce the strength, and take 15 tons or about 34,000 lbs.* on the square inch **« fn ^-^^^^^^y ^^ <^he material or the pressure at which a boiler would burst Ihis I should consider in practice as the maximum power of resistance of boiler plates m their riveted state, and I will now endeavor to show you in a very concise, and 1 trust not uninteresting investigation, the bearing power of boiler^ and the pressure at which they can be worked with safety. It has been stated that the strength of cylindrical boilers, when taken in the direction of their circumference, is in the raUo of their diameters, and when taken in the direction of the ends, as the squares of the diameters,— a proposition which it will not be difficult to demonstrat^ as applica- ble to every description of boUer of the cylindrical form. It will be seen, however, that tlie strain is not exactly the same in every direction, and that there is actually less upon the material in the longitudinal direction than there is upon the circumference, for example let us take two boilers, one three feet diameter and the other six feet and suppose each to be subject to a pressure of 40 lbs. on the square inch. In this condi- tion. It is evident that the area or number of square inches in the end of a three-feet of aHth?; r "-f ^ -n^K r ^ ^J}}'' '^^^''' ^"^1^^' «« 1 ^« 4 ; and, by a common proceL of t^ 1 Zn'V h'^K^-V' ^^""^ ^\'^^ *^' "^S^^ ^^ ^^'^ P^^*^« formingihe cylindrical part 40 7^'l"' Y7.0? «^^J««t (at 40 lbs. on the square inch) to a pressure of 40,7121 bs., upwards of 18 tons: whereas the plates of the six-feet boiler hive to sue- b'oiler Lrr 1 'u;f'V^'-' r ^? '""«' ^^"'^ ^« ^^^^-Pl- '^^ force to which t^ to 1 thopi^ half the diameter is exposed; and the circumference being only as 2 W hti 'noT?r'^ ^' •?/' J?' '^T "P^^ "^" cylindrical plates of the large boiler, cv irndir in. T^' "^n" ^^'^- "^¥*' P^^*" «^ ^^'^ ^^i^^^' a^ the circumference of a s&f b.?nr'' ^^^T' *^1 '^'^^^^ '^''' diameter; consequently, the pressure, iu- cnds is onh dmX'Tff '^- '^' ?'''' ^^ ?". ^^"^^« «^ ^^« ^i^'^^^ter, as shown in the thre;-fect boifer ^ circumference of the six-feet boiler being twice that of the havc^dLTrit'd^\?h^^^ '"PP^^ *^^ *^° cylindrical boilers, such as we onJnf f i!! 1 ' ^^.^^,,<^^^3^ct sup^Y vXable data in the varied requirements of boiler construction, and their comZati^e^were of «Z^;%he exltiryrr' ''"r ' ?°i compression.'-(i^r. Flrbai::^sT:ure) )t I om the existing state of our knowledge, we must rest satisfied with the fact that the resisting powers of cylindrical flues to%ompression will bHi^eTuy as their di^ r.t TV *n ":t ™*>^^h^rcfore conclude that a circular flue 18 incCi^PdiWter w U ^^;p^:^^^^ - com -nSr^- meter" h-lZ^J'LT"'''t^ ""i '*''^'" l^'^i * high-pressure boiler 30 feet long, 6 feet dia- M Ibl' on Sir. fw 1? ^""'Y^'^ 2 f^^t Sfnches diameter, working at a pressure of foci 1 0?0 pvn?« Tf ' "^^ ^^J^ ^"^y ^ '""^^^P^y ^^^ '^^raber oflquarefeetof sur- Wer of ?heL^rln"«jr''r''; ^^ ^r'.' ^^^r ^^ ^'^^' '^'^ f«r<^« of ^'319 tons, which a pressure whe^i'^^^^^^ ^'^' to sustain. I mention this to show that the statistics of TkrwLTie o^tJie rf t^ •^'' ^^^ ^.""^"'i ^" themselves, but instructive as regards breaHf fh ^,f retaining powers of vessels so extensively used, and on which the P et re to bTat 4«oTh "^" J"" P"-««.^he subject a little further.' let us suppose the deter iption win htt! b f '''' ^^ «q"^^« i««h, which a well-constructed boillr of this ne ulv^so 000 L« K .H r '^ ^l"^^"^ *"^ ^« *^*^« ^^^ enormous force of 29.871, or "ihi^i horv • ^^ •? '^V*^'° * "y^'"*^^'' 30 feet long and 6 feet diameter. Ihis IS, however, inconsiderable when compared with the locomotive and mme 212 BOILERS. BOILERS. :.f I t. r r f f ii ^ I f if marine boilers, which, from the number of tubes, present a much larger extent of sur face to pressure. Locomotive engines are usually worked at 80 to 100 lbs. on the inch , and, taking one of the usual construction, we shall find, at 100 lbs. on the inch, that it rushes forward on the rail with a pent-up force within its interior of nearly 60,000 tons, which is rather increased than diminished at an accelerated speed. " In a stationary boiler charged with steam at a given pressure, it is evident that the forces are in perfect equilibrium, and, the strain being the same in all directions, there will be no tendency to motion. Supposing, however, this equilibrium to be destroyed by accumulative pressure till rupture ensues, it then follows that, the forces in one di- rection having ceased, the other in an opposite direction, being active, would project the boiler from its seat with a force e(jual to that which is discharged through the ori- fice of rupture. The direction of motion would depend upon the position of the rup- tured part. If in the line of the centre of gravity, motion would ensue in that direc- tion ; if out of that line, an oblique or rotatory motion round the centre of gravity would be the result. " The velocity or quantity of motion produced in one direction would be equal to the intensity or quantity lost ; and the velocity with which the body would move would be in the ratio of the impulsive force, or the quantity lost. Therefore, the quantity of motion gained by an exploded boiler in one direction will be as its weight and the quantity lost in that direction. These definitions are, however, more in the province of the mathematician, and may easily be computed from well-known formulte on the laws of motion. " We now come to the rectangular forms, or flat surfaces, which are not so well cal- culated to resist pressure. Of these we may instance the fire-box of the locomotive boiler, the sides and flues of marine boilers — the latter of which, by the by, are now superseded by those of the tubular form — and the flat ends of the cylindrical boilers, and others of weaker construction. "The locomotive boiler is frequently worked up to a pressure of 120 lbs. on the square inch, and at times, when rising steep gradients, 1 have known the steam nearly as high as 200 lbs. on the inch. In a locomotive boiler subject to such an enormous working pressure, it requires the utmost care and attention on the part of the engineer to satisfy himself that the flat surfaces of the fire-box are capable of resisLiug that pressure, and that every part of the boiler is so nearly balanced in its powers of resistance, as that, when one part is at the point of rupture, every other part is on the point of yielding to the same uniform force. This appears to be an important consideration in mecha- nical constructions of every kind, as any material applied for the security of one part of a vessel subject to uniform pressure, whilst another part is left weak, is so much material thrown away ; and iu stationary boilers, or in moving bodies, such as loco- motive engines and steam vessels, it is absolutely injurious, at least so far as the parts are disproportionate to each other, and the extra weight when maintained in motion becomes an expensive and unwieldy encumbrance. A knowledge of the strength of materials used, judicious care, and the exercise of sound judgment in its distribution, are therefore some of the most essential qualifications of the practical engineer. Our limited knowledge and defective principles of construction are manifest from the nu- merous abortions which exist, and, although I am free to communicate all that I know on the subject, I nevertheless find myself deficient in many of the requirements ne- cessary for the attainment of sound principles of construction. " Reverting to the question more immeaiately under consideration, it is, however, essential to give the requisite security to those parts which, if left unsupported, would involve the public as well as ourselves in the greatest jeopardy. " The greater portion of the fire-boxes of locomotive boilers, as before noticed, have the rectangular form, and, in order to economize heat and give space for the furnace, it becomes necessary to have an interior and exterior shell. " That which contains the furnace is generally made of copper, firmly united by rivets, and the exterior shell, which covers the fire-box, is made of iron and united by rivets in the same way as the copper fire-box. Now these plates would of themselves be to- tally inadequate, unless supported by riveted stays to sustain the pressure. In fact, witn one-tenth the strain, the copper fire-box would be forced inwards upon the furnace and the external shell bulged outwards, and with every change of force these two flat surfaces would move backwards and forwards, like the sides of an inflated bladder, at the point of rupture. To prevent this, and give the large flat surfaces an approxi- mate degree of strength with the other parts of the boiler, wrought iron or copper stays, one inch thick, are introduced ; they are first screwed into the iron and cop- per on both sides to prevent leakage, and then firmly riveted to the interior and ex- terior plates. These stays are about six inches asunder, forming a series of squares, and each of them will resist a strain of about fifteen tons before it breaks. . " Let us now suppose the greatest pressure contained in the boiler to be 200 lbs. on the 213 square inch, and we have 6 x 6 x 200 = 7,200 lbs., or S^^ tons, the force applied to a square of 36 inches. Now as these squares are supported by four stays, each capable of sustaining fifteen tons, we have 4 x 15 = 60 tons as the resisting powers of the stays, but the pressure is not divided amongst all the four, but each stay has to sustain that pressure ; consequently the ratio of strength to the pressure will be as 4^ to 1 nearly, which is a very fair proportion for the resisting power of that part. " VV e have treated of the sides, but the top of the fire-box and the ends have also to be protected, and there being no plate but the circular top of the boiler from which to at- tach staj's, it has been found more convenient and equally advantageous to secure those parts by a series of strong wrought-iron bars, from which the roof of the fire-box is sus- pended, and which effectually prevent it from being forced down upon the fire. It will not be necessary to go into the calculations of those parts ; they are, when riveted to the domo or roof, of sufficient strength to resist a pressure of 300 to 400 lbs. on the square inclu This is, however, generally speaking, the weakest part of the boiler, with the exception, probably, of the flat end above the tubes in the smoke-box, if not carefully stayed. "In the flat ends of cylindrical boilers, and those of the marine principle, the same rule applies as regards construction, and a due proportion of the parts, as in those of the locomotive boilers, must be closely adhered to. Every description of boiler used in manufactories, or on board of steamers, should in my opinion be constructed to a bursting pressure of 400 to 600 lbs. on the square inch ; and locomotive engine boilers, which are subjected to a much severer duty, to a bursting pressure of 600^) 700 Iba. ^ "It now only remains for me to state that internal flues, such as contain the furnace m the interior of the boiler, should be kept as near as possible to the cylindrical form, and as wrought-iron will yield to a force tending to crush it about one half of what would tear it asunder, the flues should in no case exceed one half the diameter of the boiler; and with the same thickness of plates they may be considered equally safe with the other parts. But the force of compression is so different from that of tension, that I should advise the diameter of the internal flues to be in the ratio of 1 to 2 i instead of 1 to 2 of the diameter of the boiler. "I will not trouble you with a description of the haycock, hemispherical, and wagon- shape boilers ; they are all bad as respects their powers of resistance, and ought to be entirely disused: I shall congratulate the public when they disappear from the list of those constructions having the confidence of the public, and the consideration of the man of science or the practical engineer. " 1° conclusion, I have to recommend attention to a few simple rules, which, if care- fully observed, will lead to the most satisfactory results. To construct boilers as nearly as possible, of maximum strength, I have already observed they should be of the cy- ! i/I^^^V "IV ^"i "^^^'u. ^i ^""^^ are used, they should be composed of plates one half thicker than those which form the circumference. The flues, if two in number, to be of the same thickness as the exterior shell ; and the flat ends to be carefully stayed ^ith gussets of triangular plates and angle iron, firmly connecting them with the cir- cumference, as per annexed sketch. "The use of gussets I earnestly recommend, as being infinitely superior to. and more certain in their action and retaining pow- ers, than stay rods. Gussets, when used, should I be placed in lines diverging from the centre of fthe boilers, and made as long as the position of the flues and other circumstances in the I construction will admit They are of great value in retaining the ends in shape, and may safely be relied upon as imparting an equali- ty of strength to every part of the structure. With these observations, I would direct atten- tion to the facts I have endeavored to incul- cate. You will, I am persuaded, find them useful ; and I trust the object contemplated by the committee of your valuable Institution „, . -x , ^^^1 **® ^^^^y attained, in the acquisition of greater security and a more perfect principle of construction."* 1501LER8 (^-x^Wn* o/).-."In a former lecture I endeavored to explain the prin- ciples on which boilers should be constructed, and the laws which govern the strength and other properties of these important vessels. The subject of construction is onl of tv nV^'T -^r^' ^"."^ ^^''^''. ^'*°™* ^'•^^^ g'^« ^^^ greatest security with the least quanti- ly^of material, may be considered as the safest examples for imitation— the true elements MembS^'o^th^SnStS' o/'K^e''""'"""^^ ^^ ^""^ ^*''^^' ^•' ^ E. F. E. 8. «id Corres^ 150 I ! 214 BOILERS. BOILERS. 216 I of construcicon. Boilers, of all other vessels, require, in the variety of their conditions^ shapes, and dimensions, the study of the philosopher as well as the hands of the me- chanic. They contain, within comparatively narrow bounds, a force which, if pro- perly governed, will propel the largest and most stately vessel against wind and tide ; perform the work of a tliousand hand?, and drive a hundred cars loaded with hundreds of tons, at the speed of the swiftest race horse, from one extremity of the kingdom to the other. They do all this and more; they impart heat and comfort to our dwellings, —are essential for the requirements of our domestic arrangements, — and under the control of judicious management, will advance the interests of commerce, and contri- bute to the enjoyments of civilized existence. " Reverse the picture, and entrust the construction and management to the hands of incapacity and ignorance, or the reckless folly and hardihood of fancied security, and death and destruction follow as a result. When the mischief is done, we then begin to guess at the causes, and to lament the inconsiderate confidence which led to the employment of incompetency, and all those errors of judgment which invariably pre- sent themselves, not before, but after the event How often do we hear of the most lamentable accidents terminating in the destruction of life and property, and how often do we lament (when too late) the causes which led to those frightful catastro- phes ! All these accidents might be prevented, and, instead of using steam, which we now do in our manufactories, at a pressure of 5 to 20 lbs. on the square inch, we might witheoual safety use it, and enjoy the advantage of its superior economy, at 60 lbs. on the inch. It shall be my duty to point out how this may be accomplished, and I hope in these endeavors to have the support of every well wisher for increased security to the public, and enlarged economy in the varied requirements of the use of steam. " Before I attempt a solution of this difficult question, I would first direct attention to a few facta which bear more directly upon the question now at issue. " Various notions are entertained as to the causes of boiler explosions, and scientific men are not always agreed as to whether they arise from excessive pressure due to the accumulation of heat, or to some other cause, such as the explosion of hydrogen gas, generated by the decomposition of water suddenly thrown on heated plates, of which we have an exceedingly indefinite conception. That of the decomposition of water is, I believe, a somewhat prevalent opinion, but I apprehend it cannot be the invariable cause, inasmuch as in that case we must assume the boiler to be nearly empty of water, and the plates over the furnace red hot. " It is not unreasonable to suppose that a force of such sudden origin, and so imme< diate and destructive in its effects, should suggest the presence of an explosive mix- ture; but I think it will be difficult, if not impossible, to account for the accumulation ofa sufficient quantity of hydrogen, without the presence of oxygen and other gases^ in their due proportions, to form an explosive compound. Now as these equivalents cannot be generated all at once by the simple decomposition of water (admitting, for the moment, that the water is decomposed), we must look for some other cause for the fatal and destructive accidents which of late years have become so prevalent " In treating of this subject, I hope to show not only what are the probable causes of explosions, but, what appears equally important, what are not the causes. So many theories (some of them exceedingly problematical) have been brought forward on the occasion of disastrous explosions, that it requires the utmost care and attention to cir- cumstances before they are generally admitted. To acquire satisfactory evidence as to the precise condition of the boiler and furnace before an explosion, is next to im- possible, as most frequently the parties in charge, and from whose mismanagement and neglect we may, in many cases, date the origin of the occurrence, are the first to be- come the victims of their own indiscretion, and we can only judge from the havoc and devastation that ensues as to the immediate cause of the event "From this it follows that, in many of the explosions on record, few, if any, of the real circumstances of the case are made known, and we are left to draw conclusions from the appearances of the ruptured parts, and the terrific consequences which too frequently follow as a result This want of evidence as to the precise condition of a boiler, with all it« valves and mountings, preceding an explosion, is much to be re- gretted, as it causes a degree of mystery to surround the whole transaction ; and the vague and sometimes inaccurate testimony of witnesses but too often baffles all attempts at research, and creates additional cause of alarm to all those exposed to the occur- rence of similar dangers. "In the discussion of this subject I shall, however, endeavor to trace, from a number of examples in which I have been personally engaged, and from others which have come to my knowledge, the causes which have led to those disastrous effects ; and provided I am successful in the discovery of the true origin of the majority of those occurren- ces, we shall have less difficulty in devifling and applying the necessary remediea for their prevention. ** In my attempts to ascertain facts by a course of reasoning which I shall have to follow in this investigation, I wish it to be understood that it is not my intention to raise doubts and fears, in the public mind, calculated to arrest the progress of commer- cial enterprise, or to cripple the energies of mechanical skilL On the contrary, I am most anxious to promote the advancement of the useful arts, to increase our confi- dence in the application of increased pressure, and to secure within moderate bounds the economical and useful employment of one of the most powerful agents ever known in the history of practical science. My object in this inquiry will, therefore, bo to enlarge our sphere of action by a more comprehensive knowledge of the subject on which it treats ; to induce greater caution along with improved construction ; and to insure confidence in all those requirements essential to the public security. " For the full consideration of this subject, it will be necessary to divide it into the following heads ; — ** 1st Boiler explosions arising from accumulated internal pressure. "2d. Explosions from deficiency of water. *' 3d. Explosions produced from collapse. "4th. Explosions from defective construction. " 5tli. Explosions arising from mismanagement or ignorance ; and " 6th. The remedies applicable for the prevention of these accidenta. **ltt. Boiler explosions arising from accumulated internal pressure. " In nine cases out of ten a continuous increasing pressure of steam, without the means of escape, is probably the immediate cause of explosion; in some instances it arises from deficiency of water, but accidents of this kind are comparativel}'^ few in cumber, as we often find, in tracing the causes, that they have their origin in undue pressure, emanating from progressive accumulation of steam of great force and density. Let us take an example, and we shall find that a boiler under the influence of a fur- nace in active combustion will generate an immense quantity of steam ; and unless this is carried off by the safety-valve or the usual channels when so generated, the greatest danger may be apprehended by the continuous increase of pressure that is taking place within the boiler. Suppose that, from some cause, the steam thus accumulated does not escape with the same rapidity with which it is generated, — that the safety-valves are either inadequate to the full discharge of the surplus steam, or that they are en- tirely inoperative, which is sometimes the case, — and we have at once the clue to the injuiious consequences which, as a matter of fact, are sure to follow. The event may be procrastinated, and repeated trials of the antagonistic forces from within, and the re- sistance of the plates from without, may occur without any apparent danger, but these experiments often repeated will at length injure the resisting powers of the material, and the ultimatum will be the arrival of the fatal moment when the balance of the two forces is destroyed, and explosion ensues. How very often do we find this to be the true cause of accidents arising from extreme internal pressure, and how very easily these accidents might be avoided by the attachment of proper safety-valves, to allow the steam to escape and relieve the boiler of those severe trials which ultimately lead to destruction] If a boiler whose generative power is equal to 100, be worked at a pressure of 10 lbs. on the square inch, the area of the safety-valves should also be equal to 100, in order to prevent a continuous increase of pressure ; or, in case of the adhesion of any of the valves, it is desirable that their areas should, collectively, be equal to IOOl If two or more valves are used, 100 or 120 would then be the measure of outlet* Un- der these precautions, and with a boiler so constructed, the risk of accident is greatly diminished ; and, provided one of the valves is kept in working order beyond the reach of interference by the engineer, or any other person, we may venture to assume that the means of escape are at hand, irrespective of the temporary stoppage of the usual channels for carrying off the steam. "So many accidents have occurred from this cause — the defective state of the safety- valves — that I must request attention whilst I enumerate a few of the most prominent eases that have come before me. In the year 1 845 a tremendous explosion took place at a cotton mill in Bolton. The boiler.^ three in number, were situated under the mill, and, from ttie unequal capacity and imperfect state of the safety-valves (as they were proba- bly fast), a terrible explosion of the weakest boiler took place, which tore up the plates along the bottom, and, the steam having no outlet at the top, not only burst out tlie end next the furnace, demolishing the building in that direction, but, tearing up the top on the opposite side, the boiler was projected upwards in an oblique direction, carrying the flours, walls, and every other obstruction before it ; ultimately it lodged itself across the railway at some distance from the building. Looking at the disastrous consequen- ces of this accident and the number of persons (from 16 to 18) who lost their lives on tlie occasion, it became a subject of deep interest to the community that a close in- vestigation should immediately be instituted, and a recommendation followed that every ««*'^K '* "i*^ ^ ^^*,*^^ ^° ®*^®'" ^''orils. viz., that the eenerative powers of a boiler being equal to a iriy«a nomber of square inches of area, say 60, the area of the safety-valve should also bo fiO. .2ie BOILERS. m i M li precaution should be used in the construction as well as the management of boil- ers. " The next fatal occurrence on record in this district was a boiler at Ashton-under- Lyne, which exploded under similar circumstances, namely, from excessive interior pressure, when four or five lives were lost ; and again at Hyde, where a similar acci- dent occurred from the same cause, which was afterwards traced to the insane act of the stoker or engineer, who prevented all means for the steam to escape by tying down the safety-valve. "There was a boiler explosion at Malaga, in Spain, some years since, and my reason for noticing it in this place is to show that explosions may be apprehended from other causes than those enumerated in the divisions of this inquiry, and one of these is in- erustation. Dr. Ritterbrandt says, in a paper read before the Institution of Civil En- gineers by an eminent chemist, Mr. West — 'That a sudden evolution of steam under eircuinstanoes of incrustation is no uncommon occurrence.' In several instances I have known this to be the case, particularly in marine boilers, where the incrustation from salt water becomes a serious grievance, either as regards the duration of the boiler, or the economy of fuel. " If it were supposed, as Dr. Ritterbrandt observes, that the boiler was incrusted to the extent of half an inch, it would at once be seen that nothing was more easy than to heat the boiler strongly, even to a red heat, without the immediate contact of water. Under these circumstances, the hardened deposits, being firmly attached to the plates, andiorniing an imptrfoct conductor of heat, would tend greatly to increase the tempe- rature of the iron ; and the difference of temperature, thus induced between the iron and the incrustation, and the greater expansibility of the iron, would cause the incrustation to separate from the plates, and the water rushing in between them would generate a considerable charge ot highly elastic steam, and thus endanger the security of the boilers. "Tliese phenomena were singularly exemplified in the Malaga explosion, which in thus described by Mr. Hick; — 'I have ascertained that a very thick incrustation of salt was formed on the lower part of the boiler, immediately over the fire, and so far as it extended the plates appear to have been red hot, being thereby much weakened, and hence the explosion. The ordinary working pressure of the boiler is 130 lbs. per square inch, and perhaps at the time of the explosion \evy much above that pressure, as there was only one small safety-valve of two and a-half inches diameter. The boiler was only two feet six inches diameter, and twenty feet long.* *' Incrustation, exclusive of being dangerous, is attended with great expense and mjury to the boiler by its removal. In the case of the transatlantic, oriental, or other long sea-going vessels, even after the use of brine-pumps, blowing out, Ac., a very large amount of incrustation is formed, and considerable sums of money are expended each voyage to remove it. " Other explosions of a more recent date are those which occurred at Bradford and Halifax. They are still fresh in the recollection of the public mind, and are so well known as not to require notice in this place. "I cannot, however, leave this part of the subject without reverting to an accident which occurred on the Lancashire and Yorkshire Railway, whichhad its origin in the same cause — excessive internal pressure. This accident is the more peculiar as it led to along mathematical disquisition as to the nature of the forces which produced results at once curious and interesting. The conclusions which I arrived at, although practi- cally right, were, however, considered by some mathematically wrong, as they weie firm- ly combated by several eminent mathematicians; but notwithstanding the number of sJgebraic formulas and the learned discussions of my friends on that occasion, I have been unable to change the opinions I then formed, for others more conclusive. •'The accident here alluded to occurred to the 'Irk' locomotive engine, which, in February, 1745, blew up and killed the driver, the stoker, and another person who was standing near the spot at the time. A great difference of opinion as to the cause of this accident was prevalent in the minds of those who witnessed the explosion, some attri- buting it to a crack in the copper fire-box, and others to the weakness of the stays over the top. Neither of these opinions was, however, correct, as it was afterwards demon- strated that the material was not only entirely free from cracks and flaws, but the stays were proved suflicient to resist a pressure of 150 to 200 lbs. on the square inch. The true cause was afterwards asceitained to arise from the fastening down of the safety-valve of the engine (an active fire being in operation under the boiler at the time), which wa» under the shed, with the steam up, ready to start with the early morning train. The ef- fect of this was the forcing down of the top of the copper fire-box upon the blazing em- bers of the furnace, which, acting upon the principle of the rocket, elevated the boiler and engine of 20 tons weight to a height of 30 feet, which, in its ascent made a summerset in the air, passed through the roof of the shed, and ultimately landed at a distance of 60 yards from its original position. The question which excited most interest, was the ab» solute force required to fracture the fire-box, its peculiar properties when once liberated. BOILERS. 217 and the elastic or continuous powers in operation which forced the engine from its place to an elevation of 30 feet from the position in which it stood. An elaborate mathe- matical discussion ensued relative to the nature of these forces, which ended in the opinion that a pressure suffieient to rupture the fire-box, was, by its continuous action, sufficient to elevate the boiler and produce the results which followed. Another rea- son was assigned, namely, that an accumulated force of elastic vapor, at a high tem- perature, with no outlet through the valves, having suddenly burst upon the glowing embers of the furnace, would charge the products of combustion with their equivalents of oxygen, and hence explosion foTlowedi Whether one or both of these two causes were in operation is probably difficult to determine ; at all events, we have in many instances precisely the same results produced from similar causes, and unless greater precaution is used, in the prevention of excessive pressure, we may naturally expect a repetition of the same fatal consequences. "The preventives against accidents of this kind are, well-constructed boilers of the strongest form, and duly proportioned safety valves; one under the immediate con- trol of the engineer, and the other, as a reserve under the keeping of some competent authority. " ^d. Erplodons by deficiency of water. "This division of the subject requires the utmost care and attention, as the circum- stance of boilers being short of water is no unusual occurrence. Imminent danger frequently arises from this cause; and it cannot be too forcibly impressed upon the minds of engineers, that there is no part of the apparatus constituting the mountings of a boiler which require greater attention — probably the safety-valves not excepted — ^tiian that which supplies it with water. A well-constructed pump, and self-acting feeders, when boilers are worked at a low pressure, are indispensable ; and where the latter cannot be applied, the glass tubular gauge, steam, and water cocks must have more than ordinary attention. " In a properly constructed boiler every part of the metal exposed to the direct action of the fire should be in immediate contact with the water, and, when proper provision is made to maintain the water at a sufficient height above the part of the plates so exposed, accidents can never occur from this cause. "Should the water, however, get low from defects in the pump, or any stoppage of the regulating feed valves, and the plates over the furnace become red hot, we then risk the bursting of the boiler, even at the ordinary working pressure. We have no occasion, under such circumstances, to search for another cause, from the fact that the material when raised to a red-heat has lost about five-sixths of its strength, and a force of less than one-sixth will be found amply sufficient to bear down the plates direct upon < the fire, or to bui*st the boiler. " When a boiler becomes short of water, the first, and perhaps the most natural, action is to run to the feed valve, and pull it wide open. This certainly remedies the deficiency, but increases the danger, by suddenly pouring upon the incandescent plates a large body of water, which, coming in contact with a reservoir of intense heat, is calculated to produce highly elastic steam. This has been hitherto controverted by several eminent chemists and philosophers ; but I make no doubt such is the case, unless the pressure has forced the plates into a concave shape, which for a time would retard the evaporization of the water when suddenly thrown upon them. Some curious experimental facts have been elicited on this subject, and those of M. Boutigny, and Professor Bowman, of King's College, London, show that a small quantity of water projected upon a hot plate does not touch it; that it forms itself into a globule sur- rounded with a thin film, and rolls about upon the ])late without the least appearance of evaporation. A repulsive action takes place, and these phenomena are explained upon the supposition that the spheroid has a perfectly reflecting surface, and conse- quently the heat of the incandescent plate is reflected back upon it What is, how- ever, the most extraordinary in these experiments, is the fact that the globule, whilst rolling upon a red hot plate, never exceeds a temperature of about 204° of Fahr. ; and in order to produce ebullition, it is necessary to cool the plate until the water begins to boil, when it is rapidly dissipated in steam. "The experiments by the committee of the Franklin Institute on this subject, give some interesting and useful results. That committee found that the temperature at which clean iron vaporized drop of water was 334° of Fahr. The development of a repulsive force which I have endeavored to describe was, however, so rapid above that temperature, that drops which required but one second of time to disappear at the temperature of maximum evaporation, required 152 seconds when the metal was heated to 395° of Fahr. The committee go on to state that — ' One ounce of water introduced into an iron bowl three-sixteenths of an inch thick, and supplied with lieat by an oil- bath, at the temperature of 546°, was vaporized in fifteen seconds, while, at tlie initial temperature of 507°, that of the most rapid evaporization was thirteen seconds.* A iijt li '£i^ 'In ! \U • It ■ 218 BOILERS. sav lorn n?lT^ however, hold good in every case, as an increased quantity of water Bay from one-eighth of an ounce to two ounces, thrown UDon heated nlai^.?; ^^t ' temperature of vaporization from 460° to 600° Fah^ Zs clar^v stt;./], f.K^ " Sd. Axploswns produced from collapse circumstance of thrtJnS!.^ J and destroyed and scalded every thing before it A mmMMmm deficieneyV wS in thf toiler ' '"'^^•''"* treated,-explosio„s from a forms. generated by it produces death m one of its worst and most painful ..TK- ^'^P^'^'l^'^'/^oyn defective construction. attention; anTon'^^il^t'shtlirmv" ^^T^^^^"^ '^''' '^^ P^^'^ -^^^^ our already shown the nature o^the stS anl^th "^ 'ir^'^f ' ^^ ^ P''^^^""« ^"^"^^^ ^ ^^^« usedin^he constructionTboiler^l^LbL^^^^^^ shown the distribution and pSn in whrch fh;f I, *^?7 ««♦, however, in all cases to attain the maximum of st^en^h and ^S^ '^^"^^ ^^ placed in order sisting powers of vessels suS sompHr^^^''^''**'' '"'""'^ ^° '^' '^' subject ^f such importance tCt I sll iTe rdtr X^^^^^^^^^^^^ ™' '' * time, in endeavoring to point out the advanWes pecuffi^^^^ sound and perfect system of construction ^ Peculiar to form, and the use of a ^e/e2^''^n:LlW^^^^^ -/>/tca6/. for the prevention of accidents arising from expl<^ «;nl??/l°^ '^''^'^^^ '" ^^^ foregoing remarks most of the causes incident to boiler exolo. sions, It now only remains to draw such inferences as will point out the circ imstonc^ which It IS desirable to cultivate, and others which it is desirable to avoid ThL! circumstances I have endeavored to class in such a way as to bring tl^e subieclor^^ mmently forward, and to point out under each head fir<;t tl,P p«„=1 i • 1 1 J! ^ - dent; and, secondly, the Sieans necessary to be obJer^^^^^^ summary, it may not be inexDedient hrl^fl^ f« ^^«!.I-* i * ?il ^ in a general loys of tin ana lead, with a small portion of Lm„th [nTu'h proL.^ ^ •>? "* "'^ fusion at a tcmperatupo sometliing beW that of moltenTa/ K ' "'.r'" '"'""■« importance is attached to these alloys, and, in o °de"to cLure c.rt." ♦ """t '?..' ^'^^ proportions, the plates are prepareVat the royal mint Ther^f^y " *," ""*' '^f ""« Suly prepared for use. In thir country the^\noT arl no? ^IjrllJf ^ '" P"?""*'! this respect I think we are wron^ as boiler explo^{L\™"n°«\rfre;'l;r^^t « in this country, and high-pressure steam, from its superior economy, is more extensively used in France than in England. In my own practice I invariably insert a lead rivet, one inch in diameter, immediately over the fireplace, and as common lead melts at 620°, I have invariably found these metallic plugs a great security in the event of a scarcity oi water in the boiler. I am persuaded many dangerous explosions may be avoided by the use of this simple and effective precaution ; and as pure lead melts at 610° we may infer from this circumstance that notice will be given and relief obtained before the internal pressure of the steam exceeds that of the resisting powers of the heated plates. As this simple precaution is so easily accomplished, I would advise its general adoption. It can do no harm to the boiler, and may be the means of averting explosions and the destruction of many valuable lives. *• The fusible metal plates, as used in France, are generally covered by a perforated metallic disc, which protects the alloy of which the plate is composed, and allows it to ooze through as soon as the steam has attained the temperature necessary to insure the fusion of the plate. The nature of the alloy is. however, somewhat curious, as the dif- ferent equivalents have different degrees of fluidity, and the portion which is the first to melt is found out by the pressure of the steam causing the adhesion of the less fusible parts, but in a most imperfect state, and incapable of resisting the internal force of the steam. The result of these compounds is the fusion of one portion of the alloy and the fracture of the other, which is generally burst by pressure. "This latter description of fusible plates is different from the lead plug over the fire, which is fused at 600° by the heat of the furnace, and the other, by the temperature of the steam, when raised to the fusible point of the alloy, which varies from 280° to 860°. "Another method is the bursting plate, fixed in a frame and attached to some con- venient part of the upper side of the boiler ; this plate is to be of such thickness and of Buch ductility as to cause rupture whenever the pressure exceeds that of the weight oa the safety valve. There can be no doubt that such an apparatus, if made with a sufii • ciently large opening, would relieve the boiler ; but the objections to this and several other devices are the frequent bursting of those plates, and the effect every change of pressure has upon the material in reducing its powers of resistance, and thus increasing uncertainty as to the amount of pressure in the boiler, as well as the constant renewal of the plates. " It has already been noticed that one of the most important securities against ex- plosions is a duly proportioned boiler, well constructed ; and to this must be added ample means for the escape of the steam on every occasion when the usual channels have been suddenly stopped. The only legitimate outlets under these circumstances appear to me to be the safety-valves, which, connected with this inquiry, are indispensable to security. Every boiler should, therefore, have two safety-valves, of sufficient capacity to carry off the quantity of steam generated by the boiler. One of these valves should be of the common construction, and the other beyond the reach of the engineer or Any other person. " Fig. 153 is a sketch of a lock-up safety-valve, as constructed by Mr. Fairbairn. a is the valve, b is a shell of thin brass, opening on an hinge and secured by a padlock ; it 18 of such a diameter as to allow the waste steam to escape in the direction of the arrows. c is the weight, which may be fixed at any part of the lever to give the desired amount of pressure, but which cannot be fixed or altered unless the boiler is opened to allow a man to get inside. d is a handle, having a long slot, by which the valve may be re- lieved or tried at any time, to obviate the liability of its cor- roding or being jammed; the engineer cannot, however, put any additional weight upon the valve by this handle. "Whilst tracing the causes of explosions from a deficiency of water in the boiler, I have recommended aa the usual precautions, ^ood pumps, sell- acting feeders, water cocks, gla^s gauges, floats, alarms, and other indicators which mark the changes and variutioas in th« height of the water. To these may be added the steam wliistlc, but chiefly tlie constant inspection of a careful, sober, and ju- dicious engineer. Above all o'^hei* -ncaris however ingeniously devised, this is the most 153 i 222 BOILERS. BONES. 228 r. It- ■ :'.M 'Tf » I i it II : i' r . essential to security, for on that official depends, not only the security of the property under his charge, but also the interests of his family, and the lives of all those within the immediate influence of his operations. One of the most important considerations in this and every other department of management is cleanliness and the careful atten- tion of a good sober engineer. " Explosions produced from collapse have their origin in different causes to those arising from a deficiency of water, and the only remedy that can be applied is the vacuum valve and the cylindrical or spheroidal form of boiler. " Defective construction is unquestionably one of the greatest sources of the frightful accidents which we are so frequently called upon to witness. Ko man should be alFowed unlimited exercise of judgment on a question of such vital importance as the construc- tion of a boiler, unless duly qualified by matured expenence in the theoretical and practical knowledge of form, strength of materials, and other requirements requisite to insure the maximum of sound construction. It appears to me equally important that we should have the same proofs and acknowledged system of operations in the construction of boilers, as we have in the strength and proportions of ordnance. In both cases we have to deal with a powerful and dangerous element; and I have yet to learn why the same security should not be given to the general public as we find so liberally extended to an important branch of the public service. In the ordnance department at Woolwich (with which I have been more or less connected for some years) the utmost care and precision is observed in the manufacture of guns; and the proofs are so carefully made under the superintendence of competent officers, as to render every gun perfectly safe to the extent of 1000 to 1200 rounds of shot. "Boilers and artillery are equally exposed to fracture, and it appears to me of little moment whether the one is burst by the discharge of gunpowder, or the other by the elastic force of steam. "Taking into consideration all the circumstances connected with the bursting of boilers and the bursting of guns, and looking at the active competition which exists, and is likely to be extended, in manufactories, railway traffic, and steam navigation, rendering it every day more desirable to reduce the cost by an extended use of steam at a much higher pressure, it surely becomes a desideratum to secure the public safety by the introduction of some generally acknowledged system of construction that wiU bear the test of experience, and involve a maximum power of resistance. The most elaborate disquisitions have taken place, by the most distinguished men of all ages since the invention of gunpowder, to discover the strength and form of guns of every description. tSurely boilers are equally if not more important, as the sacrifice of human life appears to me much greater in the one case than the other. It is therefore a sub- ject of paramount importance to the public to know that the facts of scientific inquiry, and the knowledge of practical skill, have combined to give undeniable security as well as confidence, that boilers are properly constructed, and capable of bearing at least »ix times their working pressure. " On the question of explosions arising from mismanagement and ignorance, we have little further to add ; and it now only remains to state, that the subject of security from boiler explosions is of such importance as to call for more able exponents than mj'self. I have endeavored to trace the causes of these lamentable occurrences, and to draw such deductions therefrom as I trust may be useful in at least mitigating, if not almost entirely' averting, the danger. " I repeat the means of prevention and the precautions necessary to be observed in the construction and management of boilers. " Ist To avoid explosions from internal pressure, cylindrical boilers of maximum forms and strength must be used, including all the necessary appendages of safety-valves, <&c. " 2d. Explosions arising from deficiency of water may be prevented by the fusible alloys, bursting plates, good feed pumps, water gauges, alarms and other marks of in- dication ; but above all, the experienced eye and careful attention of the engineer is the greatest security. " 3d. Explosions from collapse are generally produced from imperfect construction, which can only be remedied by adopting the cylindrical form of boiler, and a valve to prevent the formation of vacuum in the boiler. "4th. Explosions from defective construction admit of only one simple remedy, and that is, the adoption of those forms which embody the maximum powers of resistance to internal pres^sure, and such as we have already recommended for general use. " Lastly. Good and efficient management, a respectable and considerate engineer, and the introduction of such improvements, precautions, and securities as we have been able to recommend, will not only ensure confidence, but create a better system of manage- ment in all the requirements necessary to be observed for the prevention of steam boiler explosions. {Fairhairn, in Lecture at Leeds.) BOMBAZINE. A worsted stuff, sometimes mixed with silk. BONES. (0,», Fr. ; Knochen^ Germ.) They form the frame work of animal bo M3 5 63-04 11-3 1-16 1-20 333 57-35 3-85 2-05 3-45 100-00 100-00 The most essential difference in the composition of these bones is that those of man contain three times as much carbonate of lime as those of the ox ; and that the latter are richer in phosphate of lime and magnesia in the same proportion. Fernandez de Barros has established a comparison between the phosphate and carbonate of lime in the bones of different animals. He found in 100 parts of earthy sa.H of the bones of the following animals : — Lion Sheep Hen Frog Fish Phosphate oflime 95-0 80-0 83-9 95-2 91-9 Carb. lima. 2-5 19-3 10-4 2-4 5-3 The bones of fish are divided into those which contain earthy salts and those which have none, called cartilaginous fishes. The enamel of the teeth is composed as follows : — Phosphate of lime with fluate of lime - - - Carbonate of iime ----«. Phosphate of magnesia ------ Soda .--.....- Brown membranes attached to the tooth, alkali, water Human eaaniel. 88-5 8-0 1-5 0-0 2-0 100-0 Ox enamol. 850 7-1 3-0 1-4 3-5 1000 In the arts, the bones are employed by turners, cutlers, manufacturers of animal char- coal, and, when calcined, by assayers for making cupels. In agriculture, they arc employed as a manure, for which purpose they should be ground in a mill, and the pow- der sowed along with the seeds in a drill. It is supposed, in many cases, to increase the crop in weight of grain and straw together, by from 40 to 50 per cent. In France, soup is extensively made by dissolving bones in a steam-heat of two or three days' continu- ance. The shavings of hartshorn, which is a species of bone, afford an elegant jelly : the shavings of calves' bones may be used in their stead. Living bones acquire a red tinge when the animals receive madder with their food ; but they lose it when the madder is discontinued for some time. Tlie following analysis of the middle part of the thigh-bone of a man of 80 years of age by Marchand, merits confidence : — 1. Cartilage insoluble in muriatic acid 2. Do. soluble in do. . 3. Blood-vessels and nerves . 4. Subphosphate of lime . . . . 5. Fluoride of calcium .... 6. CHrbonate of lime . . ,. , 7. Phosphate of magnesia 8. Soda ....... 9. Chlorsodium . ... 10. Oxides of iron and manganese, and loss 27-23 6-02 1-01 52-26 1-00 10-21 1-06 , 0-92 0.25 1.06 100-00 The human bonea contain much more carbonate of lime than those of oxen ; which are, however, richer in phosphate of lime and magnesia. The proportion of cartila- ginous matter in bones is not uniform, but varies in the same species of animal with age, sex, and pasture. The quantity of bones imported in 1850 amounted to 27,198 tons, and in 1851 to 81,956 ttms. BONE BLACK. 225 BONE BLACK (Noir (Tos, Fr. ; KnochanschwarUy Germ.), or Jnimal ckarcoaly as it is less correctly called, is the black carbonaceous substance into which bones are converted by calcination in close vessels. This kind of charcaol has two principal applications : to deprive various solutions, particularly sirups, of their coloring matters, and to furnish a black pigment. The latter subject will be treated of under Ivory Bi:.ACK. The discovery of the antiputrescent and decoloring properties of charcoal in general, is due to Lowitz, of Petersburg ; but their modifications have occupied the attention of many chemists smce his time. Kels published, in 1798, some essays on the discolonng of mdigo, saffron, madder, sirup, &c. by means of charcoal, but he committed a mistake m supposing bone black to have less power than the charcoal of wood. The first useful application of charcoal to the purification of raw colonial sugar was made by M. Guillon, who brought into the French markets considerable quantities of fine sirups, which he discolored by ground wood charcoal, and sold them to great advantage, as much superior to the cassonades of that time. In 1811, M. Figuier, an apothecary at Montpeliier, published a note about animal charcoal, showing that it blanched vinegars and wines with much more energy than vegetable charcoal; and, lastly, in 1812, M. Derosnes proposed to employ animal charcoal in the purification of sirups and sugar refinmg. The quantities of bone black left in the retorts employed bv MM Payen, for producing crude carbonate of ammonia, furnished abundant materials for making the most satisfactory experiments, and enabled these gentlemen soon to ob- tain ten per cent, more of refined sugar from the raw article than had been formerlv extracted, and to improve, at the same time, the characters of the lumns bastanls treacle, &c. * » «*oi.«iiuj». The calcination of bones is effected by two different systems of apparatus- by heatin-- them m a retort similar to that in which coal is decomposed in the gas works or in small pots piled up in a kiln. For the description of the former, see Gas-Light On the second plan, the bones, broken into pieces, are put into small cast-iron not^ of the form shown in Jig. 154, about three eighths of an inch thick, two of which^e dexterously placed with their mouths in contact, and then luted tot^ether with loam The hp of the upper pot is made to slip inside of the under one. These double vessels* containing together about fifty pounds of bones, are arranged alongside, and over each other, m an oven, like a potter's kiln, till it be filled. The oven or kiln mav be either oblong or upright. The latter is represented in figs. 156, 156, 157. a is the fireplace or grate for the fuel; c c are the openings in the dome of the furnace throu-h which the flame flows ; the divisions of these orifices are shown in Jig. 157 b is the wall of bnck-work. d the space in which the pots are distributed, e is the door by which the workman carries m the pots, which is afterwards built up with fire-bricks, and plastered over with loam. This door is seen in Jig. 155. r f are the lateral flues for conveyine the disengaged gases into the air. ^ ^ 164 165 J caldnini bones T rt ^''T^V^^^-^^* ^^^' * ^^"^"^ ^^^^ «^ ^ ^-i^^^^^i ^^1" ^or is seClt^l bv a ni «r ^ fe-chamber lying upon a level with the sole of the kiln; it rolsTh^Jd arP P^ ' ^'a^ ^^^ f^.''"^"» ^'""^^^ '' ^"^ '^^ Pi"^^ or wall, several latmg thel^dS^n^rtt^^^^^^^^ ^"^'^^^ ^-P-P^-« ^- -^- ■?p 226 BONE BLACK. BONE BLACK. 227 i m- |i iii i t at once ; the greatest heat being nearest the roof of the kiln ; which resembles, in manf respects, that used for baking pottery ware. In both kilns the interior walls are built of fire-bricks. In the oblong one, the fiercest heat is near the vaulted roof; in the upright one, near the sole ; and the potp, containing the larger lumps of bones, should be placed accordingly near the top of the former, and the bottom of the latter. Such a kiln may receive about seventy double pots, containing in the whole thirty-five cwt. of bones. After the earth is filled with the pots, and the entrance door is shut, the fire is applied at first moderately, but afterwards it must be raised and maintained, at a brisk heat, for eight or ten hours. The door of the ash-pit and the damper may now be nearly closed, to moderate the draught, and to keep up a steady ignition for six or eight hours longer, without additional firing; after which the doors must be all opened to cool the furnace. When this is done, the brick-work of the entrance door must be taken down, the kiln must be emptied, and immediately filled again with a set of pot:j peviously filled with bones, and luted together ; the pots which have been ignited may, in the course of a short time, be opened, and the contents put into the magazine. But in operating with the large decomposing cylinder retort, the bones being raked out hot, must be instantly tossed into a receiver, which can be covered in air-tight till they are cool. The bones lose upon the average about one half of their weight in the calcination. In reference to the quality of the black, experience has shown that it is so much more powerful as a discoloring agent, as the bones from which it was made have been freer from adhering fatty, fleshy, and tendinous matters. The charcoal is ground in a mill, either to a fine powder and sifted, or into a coarse granular state, like gunpowder, for the preparation of which two sieves are required, one with moderately fine meshes, to allow the small dust to pass through, and one with large meshes, to separate the proper-sized grains from the coarser lumps. Either a corn-mill, an edgestone mill, or a steel cylinder mill, may be employed for grinding bone-black, and it is generally damped in the operation to keep down the fine dust. Bone-black, as found in commerce, is very variable in its discoloring power, which arises from its having been exposed either to too great a heat which has glazed its car- bon, or too low a heat which has left its albumen imperfectly decomposed. A steady ignition of due continuance is the proper decomposing temperature. Its composition is generally as follows : — Phosphate of lime, with carbonate of lime, and a little sulphuret of iron, or oxyde of iron, 88 parts; iron in the state of a silicated carburet, 2 parts; charcoal containing about one fifteenth of azote, 10 parts. None of the substances present, except the char- coal, possesses separately any discoloring power. The quality may be tested by a solution of brown sugar, or molasses, or of indigo in ftulphuric acid. The last is generally preferred by the French chemists, who have occu- pied themselves most with this subject, and it contains usually one thousandth part of its weight of this dye-drug of the best quality. Other animal substances yield a charcoal, possessed of very considerable discoloring properties. The following table by M. Bussy exhibits an interesting comparison of almost every kind of charcoal in this point of view. Table of the discoloring powers ( 3f diflerent charcoals. F Indigo test Molasses lesf Blanching by Power by Species of Charcoal. Weight. consumed. consumed. indigo. molastet. Gramme. Litres. Blood calcined with potash 1-60 0-18 50 20 Ditto with chalk - - - 0-57 0-10 18 11 Ditto with phosphate lime 0-38 0-09 12 10 Gelatine ditto with potash M5 0-14 36 15-5 Albumen ditto ditto - - 1-08 0-14 34 1,5-5 Starch ditto ditto - - - 0-34 0-08 10-6 8-8 Charcoal from acet. potash 0-18 0-04 5-6 4-4 Ditto from carb. sciia by phosphorus - - - - 0-38 0-08 12 8-8 Calcined lamp black - - 0-128 0-03 4 3-3 Ditto ditto potash - - - 0-55 0-09 15-2 10-6 Bone black treated with mur. acid and potash - 1-45 0-18 45 20 Bone black ditto with mur. acid ------ 0-06 0-015 1-87 1-6 Oil calcined with phosph. of lime - - - - - 0-064 0-017 2 1-9 Crude bone black - - - 0-032 0-009 1 1 With regard to the mode of operation of bone black on colored liquids, M. Paycn showed in his prize essay, 1. That the decoloring power of charcoal depends in general upon its state of division ; 2. That in the various charcoals, the ca/bonaceous matter acts only upon the coloring matters, combining with and precipitating them ; 3. That in the application of charcoal to the refining of sugar, it acts also upon the gluten, for it singularly promotes crj'stallization ; 4. That according to the above principles, the decoloring action of charcoals may be so modified, as to make the most inert become the most active ; 5. That the distinction between animal and vegetable charcoals is im- proper, and that we may substitute for it that of dull and brilliant charcoals ; 6. That of the substances present in charcoal besides carbon, and particularly animal charcoal, those which favor the decoloring action, have an influence relative only to the carbon ; they serve as auxiliaries to it, by insulating its particles, and presenimg them more freely to the action of the coloring matter; 7. That animal charcoal, besfles its de- coloring power, has the valuable property of taking lime in solution from water and Birup ; 8. That neither vegetable, nor other charcoals, "besides the animal, have this power of abstracting lime ; 9. That by the aid of the decolorimeter, or graduated tube charged with test solution of indigo or molasses, it is easy to appreciate exactly the dc coloring properties of all kinds of charcoal. DiflTerent varieties of lignite (fossilized wood) or even pit coal, when well carbonizec in close vessels, aflTord a decoloring charcoal of considerable value. By reducina; IOC parts of clay into a thin paste with water, kneading into it 20 parts of tar, and 500 of finely-ground pit coal, drying the mixed mass, and calcining it out of contact of air, s charcoally matter may be obtained not much inferior to bone-black in whitening sirups. The restoration of animal charcoal from burnt bones, for the purpose of sugar re- fining, has been long practised in France. Mr. W. Parker has lately made the following process the subject of a patent. The charcoal, when taken from the vessel in which it has been employed for the purposes of clarifying the sugar, is to be thoroughly washed with the purest water that can be obtained, in order to remove all the saccharine matter adhering to it. When the washing process has been completed, the charcoal is laid out to dry, either in the open air or in & suitable stove, and when perfectly free from moist- ure, it is to be separated into small pieces and sifted through a sieve, the wires or meshes of which are placed at distances of about two and a half in every inch. This sifting will not only divide the charcoal into small pieces, but will cause any bits of wood or other improper matters to be separated from it. The charcoal, thus prepared, is then to be packed lightly in cylindrical vessels called crucibles, with some small quantity of bones, oil, or other animal matter mixed with it. The crucibles are then to be closed by covers, and luted at the joints, leaving no other opening but one small hole in the centre of the cover, through which any gas, generated within the vessel when placed in the oven or furnace, may be allowed to escape. The crucibles are now to be ranged round the oven, and placed, one upon another, in vertical positions ; and when the oven is properly heated, gas will be generated within each crucible, and issue out from the central hole. The gas thus emitted, being of an inflammable quality, will take fire, and assist in heating the crucibles ; and the operation being carried on until the cruci- bles become of a red heat, the oven is then to be closed, and al- lowed to cool; after which the crucibles are to be removed, when the charcoal will be found to have become perfectly reno- vated, and fit for use as before. Bone Black, or animal charcoal restored. A process for this pur- pose was made the subject of a patent by Messrs. Bancroft and Maclnnes of Liverpool, which consists in washing the granular charcoal, or digesting it when finely ground, with a weak solu- tion of potash or soda, of specific gravity 1-06. The bone black which has been used in sugar re- fining may thus be restored, but it should be first cleared from all the soluble filth by means of water.. Mr. F. Parker's method, patent- ed in June, 1839, for efiFecting a like purpose, is by a fresh caloiiid^ tion as follows : — 1 iiyyj'Z/yyyy/yyyyyyyyyyyyyjWA'//y^. , •iS I* I I'- ■ 228 BOOKBINDING. Fig. 160 represents a front section of the furnace and retort : and fia 161 is a tran. Terse vertical section of the same, a is a retort, surrounded by'the fl^S' of the furnace b ;c ,8 a hopper or chamber, to which a constant fresh supply of the black is furnished ^ *vlf T'^v^.P''*^"^ has been withdrawn, from the lower part of a j is the tot- ing vessel, which IS connected to the lower part of the retort a by a sand joinVr The cooler ^18 made of thm sheet iron, and is large ; its bottom is closed withH^de pla e ^n.l^K ff ffter passing slowly through the retort a into the vessel ± gets so much Xw T.J.. f' VT '* '"^^''A ^Y ^ P"^^^^^ ^^^* "^^y be safely withdrfwn so^to mS^BAmfc^7.^f^^^^^^ V' '^f '^""''^^^ meter, Vith aslidedoor them'^wihXcrandsld: Wrl"""^ '^^^'"^^ ^'^ ^^^^^^ '' ' ^-^' ^^ --"^S ~T^?sSlVpT/t%!S '^^ P'"'"^^ "?^"' ^^ V^'^^^ed in the following nianner • th^r J' "^al^e them solid and smooth, And are then condensed in a pres. AneV quartos, or any smaUer size. The backs a?e no;%?„':j7a"d L e^ds tel^T.r^ opened and scraped with a knife, that they n,ay be*D>ore conveniemly fi/el to Ss^e board sides; aAer which the back is turned with a hammer the bonk hein» fil/* press between boards, called backing boards, in order to make a give for al"mL'^he p«teboard s.des. When these sides are applied, holes are madeTthm f™ Zi ^e the bands through, the superfluous end^i are n ^^"' r r*^"8^J*'- g'-^oves in the upright posts, for^the'^rojectin.^ enS of this n?pUT r'' ^^^^«'/>^^.«"d« "P and down in.^ In the middle of^hiundeVside Lrew? whio{' tl't "' \^'^' ^'^''' ^^^^^^ »^ * ••^'^'^^ ^^^^^s> to receive the top of thi b^h^ fi^lv tn r ? '^^ ^%'i ''•*" "°'' P'^^^ '^> ^ilarly iade with the former, but bolted firmly to the posts c c. Upon the screw g, there is a circular handle or ring i, for 166 S^^ns rfTLlr ^''''Jt'"'' ir"^'"*')- O'er it cross holes IW ti,lue„i„, the pr«, 1 n9 M«' Across the middle of this board, and narallpl t^^TI '■ Tl ! made fast, which fits into a grc^ie in the^ottom „r .^ ^"Ti^ \ \ '^' *^"?"^ P'^^« '" " of this is seen at fig- 168, andTmmediLtelv und^r fh^ • '* • ^^^"^•'"tal representation and/, connected tcfgeihe;,andnde^ew^ i' 1'° '"^]^,f'* ""'^ ^^^^ °^ ^ is a pin for a circular bo^d n,^o ^ u^n^^d^'S^^^^^^^^ ^^« ^?^V> « material to be cut," with a saving piece between Tt^n,! ti ^^."«^,^ard is placed the be divided upon its edge into any n^ber of paS L^L^ J>^^^^^^ ^^"^ ""^'"^ " ^ the board I, to point to each. ^ required, with a stationary index on It will now be understood that the « material to be rut » «,«„ k * j thecen.™ pia of the board »,a„J aUo that Jh'u'irAe ririla'"rshS\"X ward and forward under the top cross piece a, and between the side slide slips fe fe, the ' surfaces of which should also be divided into inches and tenths. The plough, fig. 169, shown in several positions, is made to receive two knives or cutters as the " material to be cut" may require, and which are situated in the plough as I now describe. The plough is composed of three principal parts, namely, the top, and its two sides. The top o, is made the breadth of the cross piece a, and with a handle made fast thereon. The sides 'p />, are bolted thereto, with bolts and nuts through corresponding holes in the top and sides. The figures below give inside views, and cross sections of the details of the manner in which the cutters and adjustments are mounted. A groove is cut down each cheek or side, in which are placed screws that are held at top and bottom from moving up and down, but by turning they cause the nuts upon them to do so ; they are shown at q q. These nuts have each a pin projecting inwards, that go into plain holes made in the top ends of cutters r r. The 169th and following figs, are | in scale. The cutters, and the work for causing them to go up and down, are sunk into the cheeks, so as to be quite level with their inner surfaces. Fig. 170 shows one of those screws apart, how fixed, and with moveable nut and projecting pin. The top of each screw terminates with a round split down, and above it a pinion wheel and boss thereon, also similarly split. This pinion fits upon the split pin. Above, there is a cross section of a hollow coupling cap with steel tongue across, that fits into both the cuts of the screw pin and pinion boss, so that when lowered upon each other, they must all turn together. In the middle and on the top of the upper piece o, the larger wheel a, runs loose upon its centre, and works into the two pinion-wheels 1 1. The wheel s has a fly-nut with wings mounted upon it. It will now be seen, when the plough is in its place as at fig. 171, that if it be pushed to and fro by the right hand, and the nut occasionally turned by the left, the knives or cutters will be protruded downwards at the same time, and these either will or will not advance as the coupling caps u u are on or off. The ribs v v, run in the grooves 6 6, fig. 165, and keep the cutters to their duty, working steadily. The top cross bar a, is the exact breadth of a bank-note, by which means both knives are made to cut at the same time. The paper is cut uniformly to one length, and accurately square. By the use of this machine, the air-pump paper-wetting apparatus, and appendant press, the paper of 45,000 notes is fully prepared in one hour and a half by one person, and may then be printed. It is not so much injured by this process as by the ordinary method of clipping by hand, soaking it, &c., which more or less opens and weakens the fabric, especially of bank-note paper. One of ihe greatest improvements ever made in the art of bookbinding is, apparently, that for which Mr. William Hancock has very recently obtained a patent. After folding the sheets in double leaves, he places them vertically, with the edges forming the back of the book downwards in a concave mould, of such rounded or semi-cylindirical shape as the back of the book is intended to have. The mould for this purpose consists of two parallel upright boards, set apart upon a cradle frame, each having a portion or portions cut out vertically, somewhat deeper than the breadth of the book, but of a width nearly equal to its thickness before it is pressed. One of these upright boards may be slidden nearer to or farther from its fellow, by means of a guide bar, attached to the sole of the cradle. Thus the distance between the concave bed of the two vertical slots in which the book rests, may be varied according to the length of the leaves. In all cases about one fourth of the length of the book at each end projects beyond the board, so that one half rests between the two boards. Two or three packthreads are now bound round the leaves thus arranged, from top to bottom of the page in diflTerent lines, in order to preserve the form given to the back of the mould in which it lay. The book is next subjected to the action of the press. The back, which is left projecting very slightly in front, is then smeared carefully by the fingers with a solution of caoutchouc, whereby each paper-edge receives a small portion of the cement. In a few hours it is sufliciently dry to take another coat of a somewhat stronger caoutchouc solution. In 48 hours, 4 ap- plications of the caoutchouc may be made and dried. The back and the adjoining part of the sides are next covered with the usual band or fillet of cloth, glued on with caout- chouc ; after which the book is ready to have the boards attached, and to be covered with leather or parchment as may be desired. We thus see that Mr. Hancock dispenses entirely with the operations of stitching, sewing, sawing-in, hammering the back, or the use of paste and glue. Instead of leaves attached by thread stitches at 2 or 3 points, we have them agglutinated securely along their whole length. Books bound in this way open so perfectly flat upon a table without strain or resilience, that they are equally comfortable to the student, the musician. 232 BORA.CIC ACID LAGOONS. I ti Siij 1841. cwta. — cwta. — cwts. — £. 8,193 1S49. 7,888 1 7,246 798 IMS. 14,986 22 18,717 861 1834. 15,060 620 15,958 422 and the merchant. The caoutchouc cement moreover being repulsive to insects, an J not affected by humidity, gives this mode of binding a great superiority over the old iiietliod with paste or glue, which attracted the ravages of the moth, and in damp situa- tions allowed the book to fall to pieces. For engravings, atlasses, and ledgers, this bind- ing 18 admirably adapted, because it allows the pages to be displayed most freely with- out the risk of dislocating the volume ; but for security, 3 or 4 stitches should be made. The leaves of music books bound with caoutchouc, when turned over lie flat at their whole extent, as if in loose sheets, and do not torment the musician like the leaves of the ordinary books, which are so ready to spring back again. Manuscripts and collec- tions of letters which happen to have little or no margin left at the back for stitching them by, may be bound by Mr. Hancock's plan without the least encroachment upon the writing. The thickest ledgers thus bound, open as easily as paper in quire, and may be written on up to the innermost margin of the book without the least inconvenience. BooKBijiDixo, 3/'""^'^^"^ ^"'^ '^^ ^"^^^^ and which consisted chiefly in boiling the substance in water with a little quicklime. kaU Tis 'o^nbLT'!! 'narrj""'',.' ''To' '?^''' ""'' "*"' ^^"^'oWe colors like .n al- opaque in ^^d v almolL,i .L ^"^ ? "^^ "^'""S ''"'"■ " effloresces and becomes tt S a Httle ih^vTf)f,.^fS "r "''''^"^ '"-"'nous, by friction, in the dark. It melts at ^^ThTn'- •'"^^"^.°"''^'^»"«d.i'""-i"tfa%£s|-iio\t.?ub^L'cT^ " ""• The following is the improved mode of purlfyins borav Th.^r-.n^ f . i be broken into small lumps, and spread unon a filler lf,!S Jit ,5 "^■*'?'' ""J" which a piece of cloth is stretched upon a wooden frame TheMnf ^'"S """" (sp. gr. 1-033) until the liquor comes off nearly colorless- thev are then HrMfZi j . getting overstocked ThT^Ltl^ .- centimes, m consequence of the market thJ ^ "versiocKea. ifte annual consumption of France in 182*? wn« 9^ nnn L-.1..C ^^a on which account the conner «=hn»i,i L^r ^"^ ' * "^^^^ effervescence ensues, contain the CuorJ When th^ Ih i ^r^""^ F^^^^^ ^^P^^^y than is sufficient ii and blanl-,.ic f« J: 7C "'""'=' °"" "^^ copper must be covered with a tisht lid finished. The Ither water fdr^^^^^^ S?' ^7"°^T' '?' .<=^y«tallization is usually for the purpose of dSsoT^i^^ /rest cT^als^rsodr'^^^^^^^^^^ ''i^^'^'^ ""^"^ detached with chisels rf^di^^nW in vTW- ^^ soda. 1 he above crystals are carefully of carbonlte of s^a' TMssltim.^ ^°' "^"^ ^^ ^"°«" '^ ^'^^^ (1000 kilos ) of borax should hrHi/^ ^' ^'P* ^'' ^'^^^^ 5 and, at least, one ton •narketable size menever ^hJ« J f- ''t^ ^l ^"'"' ^^ ^^^^^ ^^ ^^tain crystals of a K-e crj' taUizL lead chests of th. 1^ ^' • ^'"'"^f ^°"'"^ ^^^' ^' "^"^^ ^^ "^^ ofi" into Ws, enclosed iiwoSen frames «nd T ""^ ^^^'-^^l truncated pyramids, furnished with continuous bu^n^rthereSiri^^^^^^^^ T^' *^ ^^^^"^ '^^ ^'^^'' ^^r a ^kes a long Ume o^omniete i^^^^^^^^^ 18 vessels of this kind; as the solution J^ crystals\re takenZtuh cwS Ser^^^^^^^^ ""t^'V' T ^' ^^^ ^'^ '^^'^ ^ ^s become cold. cmsels, alter the liquor has been drawn ofl; and the whole tam^'n^rfiny'pir^^ ""'"^f' 7^^^^^^ from the lakes of Tuscany, con- i! Ifll ? (I i I 234 BORAX. According to Wittstein, the commercial boracic acid is compoaed as follows: — Sulphate of manganese iron alumina lime - Water magnesia . - - - ammonia . - - - soda - - - - - potash _ . - - salammonia - - - - silica (in solution) - - - ^ sulphuric acid (combined with the boracic) crystallizable boracic acid - A trace - 0-365 - 0-320 - 1-018 - 2-632 - 8-608 - 0-91'7 - 0-369 - 0-298 - 1*200 - 1-322 - 76-494 - 6-557 100-000 Dry borax acts on the metallic oxides at a high temperature, in a very remarkable manner, melting and vitrifying them into beautiful colored glasses. On this account it is a most useful reagent for the blowpipe. Oxide of chrome tinges it of an emerald green ; oxide of cobalt, an intense blue ; oxide of copper, a pale green ; oxide of tin, opal; oxide of iron, bottle green and yellow; oxide of manganese, violet; oxide of nickel, pale emerald green. The white oxides impart no color to it by themselves. In the fusion of metals borax protects their surface from oxidizement, and even dis- solves away any oxides formed upon them; by which twofold agency it becomes an excellent flux, invaluable to the goldsmith in soldering the precious metals, and to the brazier in soldering copper and iron. i. v • u Borax absorbs muriatic and sulphureous acid gases, but no others, whereby it be comes, in this respect, a useful means of analysis. , , • The strength or purity of borax may be tested by the quantity of sulphuric acid requisite to neutralize a given weight of it, as indicated by tincture of litmus. When mixed with shellac in the proportion of one part to five, borax renders that resinous bodv soluble in water, and forms with it a species of varnish. Boracic acid is a compound of 31 19 of boron and 68-81 oxygen, in 100 parts. Iti prime equivalent referred to oxygen 100, is 871-96. . i i v The following process for refining the native Indian borax, or tmcal, has been pub- lished by MM. Robiquet and Marchand : — It is put into large tubs, covered with water for 3 or 4 inches above its surface, and stirred through it several times during six hours. For 400 lbs. of the tincal there must now be added 1 lb. of quicklime diffused through two quarts of water. Next day the whole is thrown upon a sieve, to drain oflf the water with the impurities, consisting, in some measure, of the fatty matter combined with the lime, as an inso- luble soap. The borax, so far purified, is to be dissolved in 2i times its weight of boiling water, and 8 lbs. of muriate of lime are to be added for the above quantity of borax. The liquor is now filtered, evaporated to the density of 18° or 20° B. (114 to 1-16 sp. grav.), and set to crystallize in vessels shaped like inverted pyramids, and lined with lead. At the end of a few days, the crystallization being completed, the mother waters are drawn off, and the crystals are detached and dried. The loss of weight in this operation is about 20 per cent. Quantities imported - Quantities exported - Retained for consumption Nett revenue 1841. 1842. 1848. 1844 cwts. _^ 3581 847 1427 cwts. — 2435 2940 3637 cwts. — . 7798 889 349 £ 866 161 5 4 The duty on borax has been repealed. BoEAX, Dry. A considerable saving of expense in manufacturing borax, and a more ready application of the borax to use, are proposed by Saulter, as follows: — ^Take about 38 parts of pure crystallized boracic acid, pounded and sifted; mix them well with 45 parts of crystals of carbonate of soda in powder; expose the mixture upon wooden shelves to heat in a stove room ; and rake it up from time to time. The bo- racic acid and the alkali thus get combined, while the carbonic acid and water are ex- pelled; and a perfect dry borax is obtained. BOUGIE. 235 BOTTLE MANUFACTITIE. The fol- lowing mechanism for moulding bottles forms the subject of a patent obtained by Henry Rickets of Bristol, in 1822. Fig. 176 is a section of the apparatus, consisting of a square frame, a a, of iron or wood ; this is fixed in a pit formed in the floor ; b b is the base of the frame, with an aper- ture for knocking up the bottom of the bottle ; c c are four legs secured to the frame- floor b, upon which the mould is supported. The platform or stand of the mould d d has an opening in its centre for the introduction of the bottom of the would, which is raised against the bottom of the bottle by the knocker-up; e e are the sides of the mould ; and // is the top of the mould in two pieces, turning over upon the joints at g g, so as to form the neck of the bottle ; h h are levers or arms for raising and depressing the top pieces; i i is a horizontal shaft or axle, turning in bearings at each end, from which shaft two levers, k k, extend ; these levers are con- nected by upright rods, I /, to the levers or arms, h A, of the top pieces //, The weight of the arms h h, and rods / /, will, by their gravity, cause the top pieces to o^en, as shown by the dotted lines; in this situation of the mould, the melted glass is to be introduced by a tube as usual. The workman then steps with one foot upon the knob m, which forces down the rod n, and by means of a 5 hort lever o, extending from the shaft t, forces down the top pieces /, and doses the mouM, as .* een in the figure ; the glass is then made to extend itself to the shape of the mould, by blowing as usual, so as to form the bottle, and the workman at this time putting his other foot upon the knob p, depresses the rod q, and hence raises the bottom of the mould by means of the knocker- up, r, so as to form the bottom of the bottle. At the bottom of the mould a ring is introduced of any required thickness, for the purpose of regulating the capacity of the bottle ; upon which ring it is proposed to raise letters and figures, as a mould to imprint the maker's name and the size of the bottle. These moulds can be removed and changed at pleasure. Under the knob p, a collar or washer is to be introduced, of any required thickness, to regulate ihe knocking up of the bottom, by which a perfect symmetry of form is presented. In order to make bottles of diflerent sizes or forms, the mould is intended to be removed, and its place supplied by another mould of different dimensions and figure ; the lower parts of all the moulds being made to fit the same frame. Such a mould ought to be prescribed by legislative enactment, with an excise stamp to define the capacity of every bottle, and thereby put an end to the interminable frauds committed in the measure of wine and all other liquors sold by the bottle. BOUGIE. A smooth, flexible, elastic, slender cylinder, introduced into the urethra, rectum, or oesophagus, for opening or dilating it, in cases of stricture and other diseases. The invention of this instiument is claimed by Aldereto, a Portuguese physician, but its form and uses were first described by his pupil Amatus, in the year 1554. Some are solid, and some hollow ; some corrosive, and some mollifying. They generally owe their elasticity to linseed oil, inspissated by long boiling, and rendered drying by litharge. This viscid matter is spread upon a very fine cord or tubular web of cotton, flax, or silk, which is rolled upon a slab when it becomes nearly soUd by drjing, and is finally polished in the same way. Pickel, a French professor of medicine, published the following recipe for the com- position of bougies. Take 3 parts of boiled linseed oil, one part of amber, and one of oil of turpentine; melt and mix these ingredients well together, and spread the compound at three successive intervals upon a silk cord or web. Place the pieces 80 coated in a stove heated to 150° F.; leave them in it for 12 hours, adding 15 or 16 fresh layers in succession, till the instruments have acquired the jn-oper size. i'oUsh them first with pumice-stone, and finally smooth with tripoli and oil. This pro- ^^^^s.the one still employed in Paris, with some slight modifications; the chief of Which is dissolving in the oil one twentieth of its weight of caoutchouc to render the *]J°s^'*'»ce more solid. For this purpose the caoutchouc must be cut into slender shreds, and added gradually to the hot oil. The silk tissue must be fine and open, to --* •i}f ]) !, \ 236 BRAIDING MACHINE. admit of the composition entering freely among its filaments. Each successive layer ou^ht to be dried first in a stove, and then in the open air, before another is applied. This process takes two months for its completion, in forming the best bougies called elastic ; which ought to bear twisting round the finger without cracking or scaling, and extension without giving way, but retracting when let go. When the bougies are to be hollow, a mandril of iron wire, properly bent with a ring at one end, is introduced into the axis of the silk tissue. Some bougies are made with a hollow axis of tin foil rolled into a slender tube. Bougies are also made entirely of caoutchouc, by the intervention of a solution of this substance in sulphuric ether, a menstruum sufficiently cheap in France, on account of the low duty upon alcohol. There are medicated bougies, the composition of which belongs to surgical pharmacy. The manufacture of these instru- ments of various kinds forms a separate and no inconsiderable bianch of industry at Paris. MM. Feburger and Lamotte are eminent in this line. BRACES. (Bretelks, Fr. ; Hosentrdger, Germ.) Narrow fillets or bands of leather or textile fabric, which pass over the shoulders, and are attached behind and before to the waistbands of pantaloons and trousers, in the act of wearing them, for supporting their weight, and bracing them up to the body. It is a useful modern invention, super- seding the necessity of girding the belly with a tight girdle, as in. former times. BRAIDING MACHINE. (Machine a lacets, Fr. ; Bortenwerkerstuhl, Germ.) This being employed not only to manufacture stay-laces, braid, and upholsterers' cord, but to cover the threads of caoutchouc for weaving brace-bands, deserves a description in this work. Three threads at least are required to make such a knitted lace, but 11, 13, or 17, and even 29 threads are often employed, the first three numbers being preferred. They are made by means of a frame of a verj- ingenious construction, which moves by a continuous rotation. We shall describe a frame with 13 threads, from which the structure of the others may be readily conceived. The basis of the machine consists of four strong wooden uprights, a, figs. 177, 178, 179, occupying the four angles of a rectangle, of which one side is 14 inches long, the other 18 inches, and the height of the rectangle about 40 inches. Fig. 177 is a section in a horizontal plane, passing through the line ah of fig. l78, which is a vertical section in a plane passing throush the centre of the machine c, according to the line c d,fig. 177. The side x is supposed to be the front of the frame ; and the opposite side, y, the back, b, six spindles or skewers, numbered, from 1 to 6, placed in a vertical position upon the circumference of a circle, whose centre coincides with that of the machine at the point c. These six spindles are composed, 1. Of so many iron shafts or axes d, supported in brass collets e {fig. 178), and ex- tended downwards within sLx inches of the ground, where they rest in brass steps fixed upon a horizontal beam. 2. Wooden heads, made of horn-beam or nut-tree, placed, the first upon the upper end of each spindle, opposite the cut-out beam f, and the second opposite the second beam g. 3, Wooden-toothed wheels, h, reciprocally working together, placed between the beam g and the collet-beam e. The toothed wheels and the lower heads for each spindle are in one piece. The heads and shafts of the spindles No. 1 and 6, are one fifth stronger than those of the other spindles ; their heads have five semicircular grooves, and wheels of 60 teeth, while the heads of the others have only four grooves, and wheels of 48 teeth ; so that the number of the grooves in the six spindles L* 26, one half of which is occupied with the stems of the puppets i, which carry the 13 threads from No. 1 to 13. The toothed wheels, which give aU the spindles a simultaneous movement, but in different directions, i BRAN. 237 are » disposed as to bring their grooves opposite to each other in the course of rotation. K, the middle winglet, triple at bottom and quintuple at top, which serves to guide the puppets m the direction they ought to pursue. L, three winglets, single at top and bottom, placed exteriorly, which serve a like purpose. M, two winglets, triple at bottom and single at top, placed likewise exterioriy, and which serve the same purposes as the preceding; m are iron pins inserted in ihe cut-out beam g, which serve as stops or limits to the oscillations of the exterior winglets. Now, if by any moving power (a man can drive a pair) rotation be impressed upon the large spindle No. I, in the direction of the arrow, all the other spindles will neces- sarily pursue the rotatory movement indicated by the respective arrows. In this case, the 13 puppets working in the grooves of the heads of the spindles will be carried round simultaneously, and will proceed each in its turn, from one extremity of the machine to the opposite point, crossing those which have a retrograde movement. The 13 threads united at the point n situated above the centre of the machine, will form at that point the braid, which, after having passed over the pulley o, comes between the two rollers p q, and is squeezed together, as in a flatting-mill, where the braid IS ca endered at the same time that it is delivered. It is obvious that the roller p receives its motion from the toothed wheel of the spindle J\o. d, and from the intermediate wheels b, s, t, as well as from the endless ^r*"?^ ^' ,y^*^^ *^"^^^ ^^ P'^^P^^ sP^ed the wheel w, fixed upon the shaft of the roller p. The braid is denser in proportion as the point N is less elevated above the tops of the puppets; but in this case, the eccentric motion of these puppets IS much more sensible in reference to that point towards which ^j all the threads converge than when it is elevated. The threads, which must be always kept equally stretched by means of a weight, as we shall presently see, are considerably strained by the traction, occasioned by the constantly eccentric movement of the puppets. From this cause, braid- ing machines must be worked at a moderate velocity. In general, for fine work, 30 turns of the large spindle per minute are the utmost that can safely be made. The puppet or spindle of this machine, being the most importan piece, I have represented it in section, upon a scale one fourth of its ac- tual size, fig. 179. It is formed of a tube, a, of strong sheet iron weU brazed ; 6 is a disc, likewise of sheet iron, from which a narrow fillet, c, rises verticaUy as high as the tube, where both are pierced with holes! d «, through which the thread / is passed, as it comes from the bobbin! g, which turns freely upon the tube a. The top of this bobbin is conical and toothed. A small catch or detent, A, moveable in a vertical di- rection round t, falls by its own weight into the teeth of the crown of the bobbin, in which case this cannot revolve ; but when the detent is raised so far as to disengage the teeth, and at the same time to pull the thread, the bobbin turns, and lets out thread till the detent falls back into these same teeth. ;^;y 179 it Th« ♦ r .t f ^" ^[ *'"*'" ^'"'^' ^' '^ ^''^^^^ ^'^^^ ^ small weight, Z, melted upon L rro top of this skewer has an eye in it, and the bottom is recurved as is shoAvn in b^itinn 'j^ that supposing the thread comes to break, this skewer falls into the actual position in the figure, where we see its lower end extending beyond the tube a, by about J of an inch; but as long as the thread is unbroken, the skewer fc, which scItm below^the tube^^ ^*'"'^' ° *^^ eccentric movement of the puppet, does not pass out w3^1' disposition has naturally furnished the means of causing the machine to stop. Whenever one of the threads breaks. This inferior protrusion of the skewer pushes in iU= p. ogress a detent which instantly causes the band to slide from the driving pulley to ine loose pulley. Thus the machine cannot operate unless aU the threads be entire. It as fhpj"{f'"?' A.^ operative, who has 3 or 4 under her charge, to mend the threads stopped substitute full bobbins for empty ones, whenever the machine is vilw ^^^^^"^^f""^^' though it does not move quickly, makes a great deal of noise, and them tn t^ ' n T'^' T'f.^v^ ^°°^^^^ ^^^^^^ made of metal instead of wood. For Tf^V^ ^r T ' they should be made with the greatest precision, by means of appropri- BR A v^""'/?"^?^^ the teeth of the wheels, and the other peculiar parts. thP holf* / **v J -^^^vGerm.) The husky portion of ground wheat, separated by dearini nrn • i?"k* ^It ^.advantageously employed by the calico printers, in the wearing process, m which, by boUing in bran-water, the coloring matters adhering to the ■••mw r^w!mm'^^^''m»mfmim H :i 1 : ■ 238 BRANDY. . r ™«^.i*.rprl ffoods as well as ihe dun matters which cloud the mor- non-mordanled parts ^^ "^^^^f '^^^SXiwe Teries of researches concerning the operation danted portions, are removed. A Y^"^^f^fJ4'\ ^^^^ distinguished chemist and cahco of.bran in such <:^!! J^^.^^if^^^^^^^^ in the ninth number of theBuUeUn nrs:>cSdSe de^ Nine sets of experiments are recorded, wh.ch justified the following conclusions. ^ ^^^ ebullition ing either the grounds or the figures. ^rinrinal obiect is to clear white n'Va'v «p"erSSeTconcnr to prove that flour is altogether useless for the clearing boU, Tnd that Ler bran is inferior for «t'j^.n''»Uh°wheatTan are distinguishable by Jr l^el^XlgStr^f^ S^o? tf pS :KTi^rand esp^eiall, with "r ^tS \st Vantage' ia aldt^ Z'p wThe bran boil , though a little potash or sod. may be properly introduced ^h'^*"' If nower^TaTtke Hour and the starch are of 7. The peUicle of the bran is the most powerful part, ">« "°ur no use in clearing goods, but the ^""'""^''''f /"rfoUowina way In proWion " bran has considerable efficacy and s^^^^^^^^^^^ the mucilaginous substance dissolves V'l^J^;?""' ' c t^^em. Accordingly, when ^usI^Uafrd^rin a^'ea^ 'SZ^X^^S^^^^r which it had absorbed 'The'LCng chemical examination of b«n U intere^in.. ./j-^^l'iJTg^^ul at successive times with water ; the deco«K.ns, bemg 6 '^^^'^^^yX'rded by evai^ration deposite, which was separated by decantation. The c'ear liquor^ J mucilage, a -o-:^ .o^t,=,°USrgrsteCr/tt:rom"etric water of the bran ously made. • ♦!,•„ «o«ntrv tn ardent soirits distilled from wine, BRANDY. The name given m ^^//°'^'^^'^,/^°.^'^^^:^Pte portion of a peculiai and possessed of a peculiar taste and A^;^/' ^^%^^°„^,^^,^" ^ of the fermenSed sub- volalSe oil. Each variety of alcohol has an aroma f/^J^^^^^ sugar-cane, rice, stance from which it is procured; -^^^^^^''^^J^^ Procured from different growths com, or potatoes ; and it may be distinguished «^_«^^ .'t^^ P^^"^^^^^ Cognac, Aunis, ^n^^o^ngriiochlnt Srf^%te^o\T??a%^^^^^^^^ -ogni-ble by '\XLlerlowed\y experiments, that the disagreeable taste of the spirits distilled f-ient to taint a pipe of 600 litres of fine flavored spirit. The most celebrated of the French brandies, those of Cognac and Armagnac, "e sli^t- IvTecti^d to only from 0-935 to 0-922; they contain more than half their ^^lll\olvr^' t/«aHrome over therefore highly charged with the fragrant essential oil of the husk of ter, and come over V^ereiore . X ^ ^.^ ^^ ^^^^^^^ ^o a much higher '^^ ^''^thV dealer 'on ^leivTngUat Paris, rSlices it to the market proof by the addition •^'/''r;. P h?.Wv Lvored w^^^^ and water; but he cannot in this way produce so of a httle 1^2, y;S asTh^^^ of distillation of the Cognac wme. If the -t n^^'^rc^^h'brlXVvi^^^^^^^^^ ^ paper, owing to a minute portTof%Le1^;^^^^^^^^^^^ -me acetic ether, and, when long kept m oak BRASS. 289 casks, a little astringent matter. The foUowing formula may be proposed for converting a silent or flavorless corn spirit, into a factitious brandy. Dilute the pure alcohol to thf proof pitch, add to every hundred pounds weight of it from half a pound to a Znd of argoKcrudewinestone dissolved in water, a little acetic ether, and pVench wineVvLecar some bruised French plums, and flavor-stuff from Cognac; then distil the mkture with a gentle fire, m an alembic furnished with an agitator mixiure wiin a iJ^Vr^%Z^'''^A'''''^^V^', P^y ^^ ^^^^'•^d ^ith nicely burned sugar (caramel) to Sirk ' roughened in taste with a few drops of tincture of ^atech^^r oak° The above recipe will afford a spirit free from the deleterious drugs too often used to flS'-^'wh Z'"''"'^' '^' ^f ?i^ating power of British brandies; one wSch may b^^ck^ 2l A c^ °^T™^ ^ ^^^''^''^' ^" ^'^y shape, can ever be. ^ ..n^ Tt ^r^'^'^l cuivre Jaune, Fr. ; Mesnng, Germ.) An aUoy of copper and copper cCL'r^^h^r''?"'f '^ ^'"^'^'^^ ^^^^'^'^ ^^PP^^' ^'^^ ^!^ho^^^ copper clippings, with caicmed calamine (native carbonate of zinc) and charcoal in « crucible and exposing them to bright ignition. Three parts of copper wer^^f^' for three of calamine and two of charcoal. The zinc reduced to the metalhrstate bv thi agency of the charcoal, combined with the copper, into an allov which ^ ^^"""^ °^^tal by the combustion, to which ufsS^ prone' rirlt ^""P^'^"?' ^*' '^reality, their mutual affinities seem to prevent thTCin iZTa "^'' ^ ^^^ 'P/'^y absorption of the zinc into the substance of the confer Indeed, copper plates and rods are often brassed externally by exposure at a hTJh temperature to the fumes of zinc, and aftewards laminated or'^ drawn Ve spuH^s gold wire of Lyons is made from such rods. Copper vessels may be supe;ficiallv convert- edmto brass by boiling them in dilute muriatic acid containing Jome w^ne and zllic ofIomfwh«rH^ffi".,;?t^'"^ ^TV' ^^P^''"^' '"P' of copper into melted zinc till an alloy ?L oTthe 00?;^^^^^^ '°^ ^' ^"'■°^'^' "^ '^''' '^' ^^^^' ^'^d ^^^ the remaining propor^ zlnT^'^n^Tf- ''^.^K^'^l ^l'"''' ^' ^i:?^^" ^^ P^^^^S' and melted with a fresh quantity of k n^l «^tam the finished brass. Each melting takes about 8 or 9 hours. The metal one h^uTncV^iLk T^^^^ '^"//^ inches long by 26 inches broad, and from one thkd to frame rr«n .p LI T v"^ " r' *^ ?^' ^*'^ ^^^°' ^^abs of granite mounted in an iron sS^es* th^ hpit l?nl 'i'l^^ preferred to every thing else as a mould, because it pre- «\o\ecl'rVth?jlt^^^^ ^^ '''''''"^ '' ''' ^-^-^' '^' ^-P^ ^«^^ «^ the clay Le intl^lh?nl^^?^ "^ T^ "fi^y ^^"^ ^"to sheets. For this purpose they are cut bmss ro^n/ ''""'"' ^''^^'^.'' commonly about 6| inches. The cvlmders of the brass rolhng-press are generally 46 inches long, and 18 inches in diameter. The I II (, ■; r 240 BRASS. fibands are first of all passed cold through the cylinders ; but the brass soon becomes too hard to laminate. It is then annealed in a furnace, and, after cooling, is passed afresh through a rolling press. After paring off the chipped edges, the sheets are laminated two at a time : and if they are to be made very thin, even eight plates arc passed through together. The brass ia these operations must be annealed 7 or 8 times before the sheet arrives at the required thinness. These successive heatings are very expensive ; and hence they have led the manufacturers to try various plans of econo- my. The annealing furnaces are of two forms, according to the size of the sheets of brass. The smaller are about 12 feet long, with a fire-place at each end, and about 13 inches wide. The arch of the furnace has a cylindrical shape, whose axis is parallel to its small side. The hearth is hori2ontal, and is made of bricks set on edge. In the front of the furnace there is a large door, which is raised by a lever, or chain, and counterweight, and slides m a frame between two cheeks of cast iron. This furnace has, in general, no chimney, except a vent slightly raised above the door, to prevent the workmen being incommoded by the smoke. Sometimes the arch is perforated with a num- ber of holes. The sheets of brass are placed above each other, but separated by parings, to allow the hot air to circulate among them, the lowest sheet resting upon two bars of cast iron placed lengthwise. The large furnaces are usually 32 feet long, by 6| feet wide, in the body, and 3 feet at the hearth. A grate, 13 inches broad, extends along each side of the hearth, through its whole length, and is divided from it by a small wall, 2 or 3 inches high. The vault of the furnace has a small curvature, and is pierced with 6 or 8 openings, which allow the smoke to pass off into a low bell-chimney above. At each end of the furnace there is a cast-iron door, which slides up and down in an iron frame, and is poised by a counterweight. On the hearth there is a kind of railway, composed of two iron bars, on the grooves of which the carriage moves with its loads of sheets of brass. These sheets, being often 24 feet long, could not be easily moved in and out of the furnace ; but as brass laminates well in the cold state, they are all introduced and moved out together. With this view, an iron carriage is framed with four bars, which rest on four wheels. Upon this carriage, of a length nearly equal to that of the furnace, the sheets are laid, with brass parings between them. The carriage is then raised by a crane to a level with the furnace, and entered upon the grooved bars which lie upon the hearth. That no heat may be lost, two carriages are provided, the one being ready to put in as the other is taken out ; the furnace is meanwhile uniformly kept hot. This method, however convenient for moving the sheets in and out, wastes a good deal of fuel in heating the iron carriage. The principal places in which brass is manufactured on the great scale in England, are Bristol, Birmingham, and Holywell, in North Wales. The French writers affirm, that a brass, containing 2 per cent, of lead, works more freely in the turning lathe, but does not hammer so well as a mere alloy of copper and zinc. At the brass manufactory of Hegermuhl, upon the Finon canal near Potsdam, the fol- lowing are the materials of one charge; 41 pounds of old brass, 55 pounds refined cop- per (gahrkupfer) granulated ; and 24 pounds of zinc. This mixture, weighing 120 pounds, is distributed into four crucibles, and fused in a wind furnace with pitcoal fuel. The waste varies from 2| to 4 pounds upon the whole. Fig. 180 represents the furnace as it was formerly worked there with charcoal ; a, the laboratory in which the crucibles were placed. It was walled with fire-bricks. The foundations, and the filling-in walls were formed of stone rubbish, as being bad conductors of heat ; sand and ashes may be also used; 6, cast iron circular grating plates pierced with 12 holes {seefg. 181)^ over them a sole of loam, c, is beat down, and perforated with holes, corresponding to those in the iron discs ; d, the ash pit ; e, the bock, a draught flue which con- ducts the air requisite to the combus- tion, from a sunk tunnel, in communica- tion with several melting furnaces. The terrace or crown of the furnace, /, lies on a level with the foundery floor, h h, and is shut with a tile of fire-clay, g, which may be moved in any direction by means of hooks and eyes in its binding iron ring. % 180 BRASS. 241 ^S' fiom Se ^dT ^"" ^""'"^ ''' ^""^ '*^^°^ ^^' '^' '^'''^^ ^ ^''^^'^ f'o^ -bove Figx^ ISS, 184, represent the funiaces constructed more recently for the use of pitcoal fuel; A. 183 being an upright section, and /^. 184, the ground pi a? Jn this furnace the crucibles are not surrounded with the fuei but^they recefve the requisite melting heat from the flame proceeding from the grate upo^n Xh it is the key8tone^6,/5r. 186 , between the arches are spaces through which the flame rises ______ ^ ^ ^'*oni the grate c; c? is the fire door ; ['^^0j4 W^M^^M^^^ f' * slidmg tile or damper for regulat- ing or shutting off the air-draught; /, an inclined plane, for carrying off the cinders that fall through the grate, along the draught tunnel g, so that the air in entering below may not be heated by them. The crucibles are 16 inches deep, 9i wide at the mouth, 6i at the Af 1 ir,/.!, „n^ ^T^~^"'^^^^ . 1 ^ ' bottom; with a thickness in the sides of 1 inch and U below; they stand from 40 to 60 meltings. The old brass, which fills their whole capacity, is fii^t put in and melted down; the crucibles ^re now taken out and are charged w th the half of the zinc in pieces of froni 1 to 3 cub^ inches m size, covered oyer with coal ashes; then one-half of the coppe^charge is ^! troduced, again coal-dust; and thus the layers of zinc and copper are distributed S- tematel^ with coal-ashes betwixt them, till the whole charge gets finalirfS Over ^ht cmdb J^^ffll ^/5-':^'°*<^-«"« '"-"er is laid, to prevent olidizemenl of the bVis S^f. 1 If / ^"^ ?x,*^"' "^^^ ^"^ P"^'°*^ ^^^^ ^"r°»ce between the 11 holes of the grate shelf; and over them two empty crucibles are laid to be heated for the castW UK'k h' 1 ^"'/"''^ ^* *^ * ^^"^« *^« ^^^« i« ^^"^^Y to be poured out. Fifteen Eng? ntroduS nf r^' ^^\7««^°^ed in one operation ; of which six are useTat^^e mtmduction of the crucibles, and four gradually afterwards. When sheet brass is to be made the following process is pursued-— An empty crucible, called a caner (giesser), is taken out of the furnace through th# crown With a pair of tongs, and is kept red hot by placing it in a hollowSSXInln surrounded with burning coals; into this crucible the c^ontents of four o?^he meS pots are poured ; the dross being raked out with an iron scraper. As soon as thTS ing pot IS emptied. It 18 immediately re-charged in the manneV abov^ describe A and re placed in the furnace. The surface of the melted brass in the caX is swe^^^^^ stump of a broom, then stirred about with the iron rake to brinfup anv ^^^^^ matterto the surface, which is then skimmed with a little scraper^tLcrS^^ seized with the casting tongs, and emptied in the following way •_ IftJ i«r"Ti,''''-^'''''^.f''J casting sheet brass consists of tw5 slaBs of granite, a a, /fa*. 186 186 They are 5i feet long; 3 feet broad, 1 foot thick, and for greater sec^^tv ZJnl^ 'T ^^^u' * *' ?>"^"^ ^"^^^ ^* *^i^^'' a°d joined at the f^r cornerwit^h mX^^-T"- ^^%T,^ ^f «T^ ^-o-ken block,%,3ifeetlong.2« broad!ld U foundr?flnnrr^'^'°.1,'^ ""^ T^ 'l^ upon gudgeons, in bearing blocks, pLced under the toundry floor, dd, in the casting pit, e e. This is lined with bricks • and is 65 fplf Innlf laid whtrf ' ^?Pa"P«°,''^ '^^^°^ ^^^^ "^"« of the p?t the bel L/^^^^^^^^ laid which support the gudgeons. The swing-blocks arp in innK^I 11^ uiockb are broad, 15 inches thick, and are somewhat roufded upon theh^ WV ^ ^' L"""^^^ casting frame may slope a little to the horizon. T:ih?s:Vo'ks^t^^^^^^ . it !!■ 242 BRASS. //, are mortised, upon which the underelab rests freely, but so as to project about 5 inch- es backwards over the block, to secure an equipoise in the act of casting, g g are bars, placed at both of the long sides, and one of the ends, between the slabs, to determine the thickness of the brass-plate. Upon the other slab the gate h is fastened, a sheet of iron 6 inches broad, which has nearly the shape of a parallel trapezium (lozenge), and slopes a little towards the horizon. It serves for setting the casting pot upon in the act of pouring out, and renders its emptying more convenient. That gate {steinmaul) is coated with a mixture of loam and hair. The upper slab is secured to the under one in its slanting position by an armor or binding. This consists of the tension bais of wood, i klm, of the iron bars n, (3 to 3i inches broad, IJ inch thick, see the top view, fig. 186,) of a rod with holes and pins at its upper end, and of the iron screw spindle o. iTie mode in which these parts act may be understood frorc inspection of the figure. In order to lift the upper slab from the under one, which is effected by turning it round its edge, a chain is employed, suspending two others, connected with the slab. The former passes over a puUy, and may be pulled up and down by means of a wheel and axle, or with the aid of a counterweight. Upon each of the two long sides of the slab there are two iron rings, to which the ends of the chains may be hooked. The casting facea of the slab must be coated with a layer of finely ground loam ; the thinner the better. When calamine is employed, i cwt. of copper, | cwt. of calamine, and \: the volume of both of charcoal mixed, are put into seven crucibles, and exposed to heat during II or 12 hours; the product being from 70 to 72 lbs. of brass. Brass-Plate Rolling. — At Hegermiihl there are two re-heating or annealing fur- naces, one larger, 18 feet long, and another smaller, 8 J ; the hot chamber is separated from the fire place by iron beams, in such a way that the brass castings are played upon by the flames on both their sides. After each passage through the laminating press (rolls) they are heated anew, then cooled and laminated afresh, till they have reached the proper length. The plates are besmeared with grease before rolling. wrMr^>:'^m '. "Fxg. 187 shows the ground plan of the furnace and its railway ;^^. 188 the cross see- Uon; 2ctAjig. 189 the section lengthwise ; a a, the iron way bars or rails upon the floor of the foundry, for enabling the wheels of the wagon-frame to move readily back- wards and forwards ; h b, the two grates ; e c, the ash pits ; d d, the fire beams ; e e e, vents in the roof of the hot chamber/; g g, two plates for shutting the hot chamber; /*, the flue ; t, the chimney. After the rolling, the sheets covered with a black oxide of copper, are plunged into a mother water of the alum works for a few minutes, then washed in clean water, and lasiiy, smeared with oil, and scraped with a blunt knife. In rough brass and brass wares, no less than 16,240 cwts. were manufactured in ihe Prussian States in the year 1832. For musical purposes, the brass wire made in Berlin, has acquired great and merit- ed celebrity ; but that of Bii-mingham is now preferred even by foreigners. Brass Color, for staining glass, is prepared by exposing for several days thin plates of brass upon tiles in the leer or annealing arch of the glass-house, till it be oxidized BRASS. 24S to be state ; mto a black powder, aggregated in lumps. This being pulverized and sifted, is again well calcined for several days more, till no particles remain in the metallic state- when it will form a fine powder of a russet brown colour. A third calcination must now be given with a carefully regulated heat ; its quality being tested from time to time bv fusion with some glass If it makes the glass swell, and intumesce, it is properly pre- pared ; if not^ It must be still farther calcined. Such a powder communrcat^ to glass greens of various tints, passing into turquoise When thin narrow strips of brass are stratified with sulphur in a crucible, and calcined ^nL™i'd Ln T?'"'*"'' ^"^^i'' ^"^ ™*y ^^ reduced to powder. This being sifted Z l^fAT Kl 'f '" * ^l^.^^b«^*J«ry furnace for ten or twelve days become! fit for use, and is capable of imparting a chalcedony, red or yellow tinge to glass by fusion, according to the mode and proportion of using it 5 g «« uj, iusiuii. The glass-maker's red colour may be prepared by exposing small plates of brass to a moderate heat m a reverberatory furnace, till the/ are^thoroughly calcined when the imme'^:t\ u^"'' P"^"^^"^^'^^' ^"^ ^^^^^ ^ red colour.^ It i« then rial; for Brass COLOUR, as employed bj the colourmen to imitate braas, is of two tints, the red or bronze, and the yellow ifke gilt brass. Copper filings mixed with red ochr^ or bole constitute the former; a powdered brass imported ffom GeLli v is Ld for the latter Both must be worked up with varnish after being dried w'ui heat and then spread with a flat camel-hair brush evenly upon the surfacf of tL oSecl Hht b^^^ varnish is composed o 20 ounces of spirits of wine, 2 ounces of shellac, and 2 ounces^f sandarach, properly dissolved. See Varnish.) Only so much of the brai Dowdcr P™T ""'^ '' " ''"" " " "^"''^ '^' immediate lie.' (sTe CxS Brass Foi^ Dutch leaf, called Knitter or Rauschgold in Germany, is made from 30^ or4^\tok.^'''' ^«^V"t--^«^- hammer work^ed by water po^er which g[^S 3M or 400 strokes per minnte; from 40 to 80 leaves being laid over each other By this treatment it acquires its characteristic solidity and lustre. See above the proem for converting the copper superficially into brass iy the fumes of zinc ' ^ Brass, \ellow. The following ta1>le exhibit* the composition of several varieties of this species of brass. No. 1. is a cast brass of uncertain origin- 2 the bra^ briT^^'nA- '• '^' 1^-""' ^^"^^ "^ ^^^^^r& ^«^r Aix-la-ChapelleTi. and 5 th^ brass for gildmg, according to D'Arcet; 6. the sheet brass of Ron/illy ; 7. EngUsh n^r^bbluS/ood 0I Btl^^ 'T -^^^^ '' ^-- -- ^' Keustadt-Ebe^^ant^Z 1. 2. 3. 4. 5. 6. 7. 8. 9. Copper Zinc Lead Tm 61-6 35-3 2-9 0-2 646 33-7 1-4 0-2 64-8 32-8 2-0 0-4 1000 63-70 33 55 0-25 2-50 64 45 32-44 2-86 0-25 701 29-9 70 29 29-26 0-28 017 71-69 27-63 0-85' 7016 27-45 0-20 0-79 1000 99-9 100-00 lOOf.O " • 10000 UiO-37 98 60 Tlie mean proportion of the metals in yellow brass is 30 zinc to 70 copper /cwiiaA, or Red Brass, in the cast state, is an alloy of copper and zinc containinir not more than 20 per cent of the latter constituent The following v^Srarf hand'iS't'^'TV 2, 3. tombak for making gilt articles; 4. French tomLk for word handles, Ac ; 4. tombak of the Okar, near Goslar, in the Hartz; 5. yellow tomblk of Paris for gilt ornaments; 6 tombak for the same purpose from 'a fac^torvTn Hanover 8. chrysochalk; 9. red tombak from Paris ; 10. red timbak of ViennT ' Copper Zinc - Lead - Tin - . 1. 2. 3, 4. 5. 6. 7. 8. 9. 10. 820 180 15 30 82 18 3 1 823 17-5 ■ 0.2" 80 17 3 85 15 trace. 85-3 14-7 86 14 90-0 7-9 1-6 92 8 97-8 22 104-5 104 lOD-O 100 100 100 ' 100 99-5 100 100-0 See War!^.'.''^ \ P^^*«^^PP^^ *°^ \ y.eljow brass: Mannheim gold (semilor), 28 copper, 12 yeHow brass, 3 tin. «n^c"and 2I" " '" "'^' '' ""^ '^^^^ «^ ^^ ^^^ ^^ (j^^o^\ ^ Parta The specific gravity of brass is greater than the mean density of its constituent 1 i 244 BRAZIL-WOOD. BRAZIL-WOOD. 245 I i r ! ,i; \ i Tarving from 7 "82 to 8 "7 3, according to the proportion of zinc to copper. Sheet brass vanes from 8*62 to 8*62 ; brass wire from 8'49 to 8'73. Brass heated and quickly cooled becomes somewhat less dense. The specific gravity of sheet tombak (81*25 coppes + 18"75 zinc) is $"188; of tombak wire (87 "6 copper + 12'5 zinc) has been found so great as 9 "00. Brass, Malleable. It is known that common brass containing from 27*4 to 3r8 per cent of zinc, and from 71-9 to 65'8 per cent of copper, is not malleable while hot, but that articles of it must be made by casting. As it would be of great advantage in many branches of industry to have an alloy of this kind that could be worked while hot, like malleable iron, the information that such an alloy exists must be welcome to artists. By melting together 33 parts of copper, and 25 parts of zinc, there was a loss of three parts ; thus making 60 per cent copper, and 40 per cent zinc. It differs from the English specimens by containing a larger proportion of zinc, and possesses, according to M. Machts, the precious property of malleability in a higher degree than the English specimens. A piece of "yellow metal," similar in colour to this alloy, was found, on analysis, to contain 60*16 copper, and 39*7 1 zinc, which is the composition of malleable brass. It also showed great density or solidity. An alloy was prepared by melting together 60 parts copper and 40 parts zinc, which had the following properties: — The colour was between that of brass and tombak, it had a strong metallic lustre, a fine, close grained fracture, and great solidity (density). Its specific gravity at the temperature of 10° Cent, was 8*44; by calculation it ou^hi only to have been 8"08 ; thus showing that in the formation of the alloy a condensation must have taken place. Calculation shows that the alloy may be considered as a de- terminate chemical combination, for the results of the analysis veiy nearly accord with the assumption that it may be considered as composed of 3 atoms by weight of copper, and 2 atoms by weight of zinc (3 Cu + 2 Zn). The hardness of the alloy is the same as that of fluor spar ; it can be scratched by apatite (glass), consequently its hardness IB =4. The alloy is harder than copper, very tough, and is, in a properly managed fire, malleable ; so much so that a key was forged out of a cast rod. These important properties of this alloy warrant an expectation of its application to many purposes in the arts, and it would appear that they depend on its definite chemical proportions. Agreeably to the directions of M. Feyerabind, care must be taken in melting together the metals, not to permit too great a loss of zinc to take place, lest the proportions between the metals should be altered, which might not be without effect on the important properties of the alloy. With this view, it might be advantageous in practice, in place of zinc, to add, in melting, a proportionate mixture of brass to the proper proportions of copper. An alloy prepared in this way gave, on analysis, 61*44 copper, and 38*15 zinc. It is very probable that malleable brass will hereafter, in many cases, be made use of instead of the higher priced copper. BRAZING. {Eraser, Fr. ; Messing-lothung, Germ.) The soldering together of edges of iron, copper, brass, Ac, with an alloy consisting of brass and zinc, sometimes with a little tin or sUver. The surfaces to be thus united must be filed perfectly bright, and not be soiled with the fingers or in any other way. The granular or nearly pulverulent alloy is usually wetted with a paste of ground borax and water, applied in this state, dried, and then exposed carefully to bright ignition at a clear forge fire. Some workmen enclose the part to be soldered in a clay lute, but others prefer leaving it uncovered, that they may see when the solder has flowed freely, and entered into all the seams. BRAZIL-WOOD. (Boisde Femamhoucy Fr. ; Brasilienhohj Germ.) This dye-wood derives its name from the part of America whence it was first imported. It has also the names Femambuca, wood of Saint Martha, and of Sapan, according to the places which produce it. Linnaeus distinguishes the tree which furnishes the Brazil-wood by the name of Ccesalpinia crista. It commonly grows in dry places among rocks. Its trunk is very large, crooked, and fuU of knots. It is very hard, susceptible of a fine polish, and sinks in water. It is pale when newly cleft, but becomes red on exposure to the air. It has different shades of red and orange. Its goodness is determined particularly by its density. When chewed,, a saccharine taste is perceived. It may be distinguished from red saunders wood, as the latter does not yield its color to water. Boiling water extracts the whole coloring matter of Brazil-wood. If the ebullition be long enough continued, it assumes a fine red color. The residuum appears black. In this case, an alkali may still extract much coloring matter. The solution in alcohol or ammonia is stiU deeper than the preceding. The decoction of Brazil-wood, called juice of Brazil, is observed to be less fit for dyeing when recent, than when old or eren fermented. By age, it takes a yellowish- red color. For making this decoction, Hellot recommends to use the hardest water; but it should be remarked, that this water deepens the color in proportion to the earthy salt! which it contains. After boiling this wood reduced to chips, or, what is preferable, to powder, for three hours, this first decoction is poured into a cask. Fresh water is poured on the wood, which is then made to boU for three hours, and mixed with the former. When Brazd-wood is employed in a dyeing bath, it is proper to enclose it in a thin linea bag, as well as all the dye-woods in general. Wool immersed in the juice of Brazil takes but a feeble tint, which is speedfly de- stroyed. It must receive some preparations. . '^^f 7^^ *^ J^ ^® ^^^^ ^^ * solution of alum, to which a fourth or even less of tartar IS added, for a larger proportion of tartar would make the color yellowish. The wool is kept impregnated with it for at least eight days, in a cool place. After this, it is dyed in J 2 , ^"u ^ ^i?.* ^Y^^^ ^'''^''''^' ^"^ ^^^ ^""st coloring particles that are deposited, ?v u * jess beautiful color; hence it is proper to pass a coarser stuff previously through the bath. In this manner a lively red is procured, which resists pretty well the action Brazil-wood is made use of for dyeing sUk what is called false crimson, to distinguish It from the crimson made by means of cochineal, which is much more permanent. The sUk should be boded at the rate of 20 parts of soap per cent., and then alumed. The alummg need not be so strong as for the fine crimson. The silk is refreshed at the T!!'' ^"iP^ssed through a bath more or less charged with Brazd juice, according to the shade to be given. When ^ater free from earthy salts is employed, the color is too red to imitate crimson ; this quality is given it by passing the silk through a slight alkaline solution or by adding a little alkali to the bath. It might, indeed, be wash A in a hard water till it had taken the desired shade. To make deeper false crimsons of a dark red, juice of logwood is put into the Brazil bath after the silk has been impregnated with it. A little alkali may be added, according to the shade that is wanted. ® To imitate poppy or flame color, an annotto ground is given to the sQk, deeper even than when it is dyed with carthamus. It is washed, alumed, and dyed with juice of Bra- zil, to which a hltle soap water is usually added. of'aciV"^''"^^ particles of BrazU-wood are easUy affected, and made yellow by the acUon They thus become permanent colors. But what distinguishes them from madder and Kermes, and approximates them to cochineal, is their reappearing in their natural color. When they are thrown down in a stale of combination with alumina, or with oxyde of tin. These two combinations seem to be the fittest for rendering them durable. It is requisite, therefore to mquire what circumstances are best calculated to promote the formation of -nese combinations, according to the nature of tie stuff. The astringent principle, likewise, seems to contribute to the permanence of the color- shide* BrazU-wood; but it deepens its hue, and can only be employed for light The coloring particles of Brazil-wood are very sensible to the action of alkalis Which give them a purple hue; and there are several processes in which the alkalis, either fixed or volatde, are used for forming violets and purples. But the colors ob- tained by these methods, which may be easUy varied according to the purpose, arc perishable, and possess but a transient bloom. The alkalis appear not to injure the colors derived from madder, but they accelerate the destruction of most other colors. In England and Holland the dye-woods are reduced to powder by means of mills erected lor the purpose. ^J5^ ^'''^^^ ^'J^'^i^'^''^^' *^m"^'^ ^'^'^y '*^' '^ Siven to cotton by Nicaragua, or peach- wood, a cheap kind of Brazil-wood. i^«»-u- »J^^^ u^"""", ^^'"^ scoured and bleached, is boiled with sumach. It is then impreffna- IkctiTi • * solution of tin (at 5* Baurae, according to VilaUs). It should now be washed ! n„ /.J." * ^^t^ ^"i^ "* M^^^ dyeing wood, and, lastly, worked in a somewhat stale infu- sion of he peach or Brazil wood. When the temperature of this is lukewarm, the dye is wm to take better. Sometimes two successive immersions m the bath are given. It is now wrung out, aired, washed in water, and dried. M. Vitalis says, that his solution of tin is prepared with two ounces of tin and a pound ^L*''"^'"Too?^^ "^'^^ ^'^'^ P*''*^ **^ "*^*<^ ^<^i^ a^ 24«» Baume, and three parts of muri- niic acid at 22". » i- • For a rose color, the cotton is alumed as usual, and washed from the alum. It then SltoV-^ tin mordant, and is again washed. It is now turned through the dye-bath, an ope-ation which is repeated if necessary. j *^ «■ For purple, a httle alum is added to the Brazil bath. 1. For amaranth, the cotton is strongly galled, dried, and washed. UlS BREAD. BREAD. 247 I' |i i 2. Ii is passed through the black cask (tonne au noir,) see Black Dye, till it has lake* ft strong gray shade. 3. It receives a bath of lime-crater. 4. Mordant of tin. 6. Dyeing in the Brazil-wood b«lh. 6. The two last cpei-ations are repeated. Dingier has endeavored to separate the coloring matter of the different sorts of Brazil, wood, so as to obtain the same tint from the coarser as from the best Pernambuco. His process consists in treating the wood with hot water or steam, in concentrating the de- coction so as to obtain 14 or 15 pounds of it from 4 pounds of wood, allowing it to cool, and pouring into it two pounds of skim milk ; agitating, then boiling for a few minutes, and filtering. The dun coloring matters are precipitated by the coagulation of the caseous substance. For dyeing, the decoctions must be diluted with water ; for printing they must be concentrated, so that 4 pounds of wood shall furnish only 5 or 6 pounds of decoction, and the liquor may be thickened in the ordinary way. These decoctions may be employed immediately, as by this treatment they have acquired the same property as they otherwise could get only by being long kept. A slight fermentation is said to im- prove the color of these decoctions; some ground woot. 's put into the decoction to favor this process. As gelatine produces no precipitate with these decoctions, they consequently contain no tannin. Gall-nuts, however, sumach, the bark of birch or alder, render the color of Brazil-wood more durable, upon alumed linen and cotton goods, but the shade is a little darker. In dyeing wool with Pernambuco, the temperature of the bath should never be above 150° Fahr., since higher heats impair the color. According to Dingier and Kurrer, bright and fast scarlet reds may be obtained upon wool, by preparing a decoction of 50 pounds of Brazil-wood in three successive boils, and setting the decoction aside for 3 or 4 weeks in a cool place ; 100 pounds of the w«ioi are then alumed in a bath of 22 pounds of alum and 1 1 pounds of tartar, and aAerwards rinsed in cold water. Meanwhile we fill two thirds with water, a copper containing 30 pails, and heated to the temperature of 150° or 160» F. We pour in 3 pailfuls of the de- coction, heat to the same point again, and introduce 30 pounds of wool, which does not take a scarlet, but rather a crimson tint. This being removed, 2 pails of decoction are put in, and 30 pounds of wool, which becomes scarlet, but not so fine as at the third dip. If the dyer strengthens the color a little at the first dip, a little more at the second, and adds at the third and fourth the quantity of decoction merely necessary, he will obtain a uniform scarlet tint. With 50 pounds of Pernambuco 1000 pounds of wool may be dyed scarlet in this way, and with the deposites another 100 may be dyed of a tile color. An addition of weld renders the color faster but less brilliant. Earkutsch says the dye may be improved by adding some ox-gall to the bath. In dyeing cotton the tannin and gallic acid are two necessary mordants, and the color is particularly bright and durable, when the cloth has been prepared with the oDy process of Turkey red. It is said that stale urine heightens the color of the Brazil dye when the ground wood is moistened with it. The quantity of Brazil or Nicaragua wood imported into the United Kingdom in 1835, was 6,242 tons, whereof 1,811 were exported; of BraziUetto 230 tons. The duty upon the first article is 5*. per ton. BREAD (Painy Fr. ; Brod, Germ.) is the spongy mass produced by baking the leavened or fermented dough of wheal or rye flour, at a proper heat. It is the principal food of highly civilized nations. The skilful preparation of this indispensable article con- stitutes the art of the Baker. Dough baked without being fermented constitutes cakes or biscuits ; but not bread strictly speaking. Pliny informs us, that barley was the only species of com at first used for food ; and even ailer the method of reducing it to flour had been discovered, it was long before mankind learned the art of converting it into cakes. Ovens were first invented in the East. Their construction was understood by the Jews, the Greeks, and the Asiatics, among whom baking was practised as a distinct pro- fession. In this art, the Cappadaiians, Lydians, and Phoenicians, are said to have par- ticularly excelled. It was not till about 580 years after the foundation of Rome, that these artisans passed into Europe. The Roman armies, on their return from Macedonia, brought Grecian bakers with them into Italy. As these bakers had handmills beside their ovens, they still continued to be called pistores, from the ancient practice of bruis- ing the com in a mortar; and their bakehouses were denominated pistoria. In the time of Augustus there were no fewer than 329 public bakehouses in Rome; almost the whole of which were in the hands of Greeks, who long continued the only persons in that city mequainted with the art of baking good bread. 12 In nothing, perhaps, is the wise and cautious policy of the Roman government more remarkably displayed, than in the regulations which it imposed on the bakers withia the city. To the foreign bakers who came to Rome with the army from Macedonia, a number of frcedmen were associated, forming together an incorporation from which neither they nor their children could separate, and of which even those who married the daughters of bakers were obliged to become members. To this incorporation were itt- trusted all the mills, utensils, slaves, animals, every thing, in short, which belonged to the former bakehouses. In addition to these, they received considerable portions of land ; ftnd nothing was withheld, which could assist them in pursuing, to the best advantage, their highly prized labors and trade. The practice of condemning criminals and slaves, for petty offences, to work m the bakehouse, was still continued ; and even the judges of Africa were bound to send thither, every five years, such persons as had incurred that kind of chastisement. The bakehouses were distributed throughout the fourteen divisions of the city, and no baker could pass from one into another without special permission. The public granaries were committed to their care; they paid nothing for the corn em- ployed m baking bread that was to be given in largess to the citizens; and the price of the rest was regulated by the magistrates. No com was given out of these granaries ex- cept for the bakehouses, and for the private use of the prince. The bakers had besides private granaries, m which they deposited the grain, which they had taken from the pub- be granaries for immediate use ; and if any of them happened to be convicted of having diverted any portion of the grain to another purpose, he was condemned to a ruinous fine of five hundred pounds weight of gold. Most of these regulations were soon introduced among the Gauls ; but it was long be- fore they found their way into the more northern countries of Europe. Borrichius informs us that in Sweden and Norway, the only bread known, so late as the middle of the 16th century, was unleavened cakes kneaded by the women. At what period in our own his- tory the art of baking became a separate profession, we have not been able to ascertain ; but this profession is now common to all the countries in Europe, and the process of baking is also nearly the same. The French, who particularly excel in the art of bakine, have a great many different kinds of bread. Their pain bis, or brown bread, is the coarsest kind of all, and is made of coarse groats mixed with a portion of white flour. The pain bis blanc, is a kind of bread between white and brown, made of white flour and fine groats. The pain blanc, or white bread, is made of white flour, shaken through a sieve after the finest flour has been separated. The pain mollet, or soft bread, is made of the purest flour without any admixture. The pain chaland, or customers' bread, is a very white kind of bread, made of pounded paste. Pain chapele, is a small kind of bread, with a well-beaten and very light paste, seasoned with butter or milk. This name is also given to a small bread, from which the thickest crust has been removed by a knife. Pain comu, is a name given by the French bakers to a kind of bread made with four corners, and sometimes more. Of all the kinds of small bread, this has the strongest and firmest paste. Pain a la reine, queen's hretid, pain a la Sigovie,pain chapele, and pain cornu, are all small kinds of bread, differing only in the lightness or thickness of the paste. Pain gruau is a small very white bread made now in Paris, from the flour separated after a slight grinding from the best wheat. Such flour is in hard granular particles. In this country we have fewer varieties of bread, and these differ chiefly in their de- grees of purity. Our white or fine bread is made of the purest flour ; our wheatea bread, of flour with a mixture of the finest bran ; and our household bread, of the whole substance of the grain without the separation either of the fine flour or coarse bran. We have also symnel bread, manchet or roll bread, and French bread, which are all made of the purest flour from the finest wheat; the roll bread being improved by the addition of inilk, and the French bread by the addition of eggs and butter. To these may be added gingerbread, a cake made of flour, with almonds, liquorice, aniseed, rose-water, and sugar or treacle; and mastlin bread, made of wheat and rye, or sometimes of wheat and barley. We have various kinds of small bread, having various names, according to their various forms. They are, in general, extremely light, and are sweetened with sugar, currants, and other palatable ingredients. In Scotland there is a cake called short bread, made from a pretty thick dough, enriched with butter, sweetened with sugar, and seasoned with orange peel, or other kinds of spices. The process of making bread is nearly the same in all the countries of modern Europe ; though the materials of which it is composed vary with the farinaceous productions of different climates and soils. The flour of wheat is most generally employed for this pur- pose, wherever that vegetable can be reared. This flour is composed of a small portion of mucilaginous saccharine matter, soluble in cold water, from which it may be separated by evaporation; of a great quantity of starch, which is scarcely soluble in cold water, but capable of combining with that fluid by means of heat ; and an adhesive gray substance called gluten, insoluble in water, ardent spirit, oil, or ether, and resembling an animal Bl ;1* ♦if I ; ii f ,1 I 1 1 i ■ S48 BREAD. substance in many of its properties. Flour kneaded with water, forms a tough and rather indigestible paste containing all the constituent parts which we have enumerated. Heat produces a considerable change on the glutinous part of this compound, and renders it more easy of mastication and digestion. Still, however, it continues heavy and tough, compared with bread which is raised by leaven or yeast. Leaven is nothing more than a piece of dough kept in a warm place till it undergoes a process of fermentation ; swelling, becoming spongy, or fuU of air bubbles, at length disengaging an acidulo-spiriluous va- por and contracting a sour taste. When this leaven is mingled in proper proportions with fresh-made dough, it makes it rise more readily and effectually than it would do alone, and gives it at the same time a greater degree of firmness. Upon the quality of the leaven employed, the quality of the bread materially depends. The principal improvement which has been made on bread in mjuem times, is the substitution of yeast or barm in place of common leaven. This yeast is the viscid froth that rises to the surface of beer, in the first stage of its fermentation. When mixed with the dough, it makes it rise much more speedily and effectually than ordinary' leaven, and the bread is of course much lighter, and freer from that sour and disagreeable taste which may often be perceived in bread raised with leaven, either because too much is mingled with the paste, or because ii has been allowed to advance too far in he process of fermentation. . „ « , , , . i • Bread properly raised and baked differs materially from unleavened cakes, not only in being less compact and heavy, and more agreeable to the taste, but in losing its tena- cious and glutinous qualities, and thus becoming more salutary and digestible. We possess several analyses of wheat flour. Ordinary wheat (triticum hybemum mixed with triticum turgidum) contains, according to the analyses made by Vauquelin of several species of wheat flour, the followmg substances : — Species of Wheat. French wheat flour - - Hard wheat of Odessa flour- - - - - - Soft wheat of Odessa flour- - - - - - Same sort of flour - - Same sort of flour - - Wheat of the French bakers - - - - - Flour of the Paris hos- pitals (2d quality) - Ditto (3d quality) - - Water. Gluten. Starch. Sugar. Gum. Bran. Total. Water of dough 10-0 10-96 71-49 4-72 3-32 100-49 50-3 12-0 14-55 56-50 8-48 4-90 2-3 98-73 51-2 10-0 8-0 12-0 12-00 12-10 7-30 62-00 70-84 72-00 7-56 4-90 5-42 5-80 4*60 3-30 1-2 98-42 100-41 100-02 54-8 37-4 37-2 10-0 10-20 72-80 4-20 2-80 - 100-00 40-6 8-0 12-0 10-30 902 71-20 67-78 4-80 4-80 3-60 4-60 2-0 97-90 100-21 37-8 37-8 The following table of analyses merits also a place here. Species of Flour. Water. Gluten. Starch. Sugar. Gummigluten. Albumen. Bna. Flour of the triticum spelta Ditto triticum hybemum Ditto common wheat - - Ditto wheat and rye mixed (mastlin) - - 1 1 6 22- 24- 12-5 9-80 74- 68- 74-5 75-50 5-50 5-0 12- 4-22 1- 1- 2- 3-28 1-50 1-50 1-2 The first two of the above analyses were made by Vogel, the third by Proust, and the fourth by Vauquelin. Analyses of the flour of some other corns. Species of Flour. White oatmeal - - - Barley meal - - - - Starch. Mucilage. 59-00 32-00 1 2-5 9- Gluten. Albumen. 4-30 Sugar. 8-25 Of resin, 2 Husk. Of a fat oil, 2 Hordein. 55 The first analysis is by Vogel, the second by Proust. It deserves to be remarked, that the flour of Odessa contains a much greater quantit) cf sugar than the French flour. The substance indicated in the preceding table by th« Bune of gluten, is the gluten of Beccaria ; that is to say, a mixture of gluten and vegelabl* BREAD. 249 albumen. The gum of wheat is not quite identical with ordinary gum. It is a browr Motized substance, which, when treated by nitric acid, affords no mucic acid, but oxali< acid and the bitter principle of Welter. It contains besides superphosphate of lime. The last column of the first table exhibits the quantity of water necessary to convert the flour into dough of the ordinary consistence, and it is usually proportional to the quantity of gluten. The hard wheat of Odessa forms an exception in this respect ; the reason of the difference being that the starch contained in this flour is not as in or- dinary flour in a fine powder, but in small transparent grains, which resemble pounded gum, and absorb less water than pulverulent starch. The triticum monococcon, according to Zenneck, contains in its unsifted flour, 16-334 of gluten and vegetable albumen ; 64-838 of starch ; 1 1-347 of gum, sugar, and extractive ; ZirfL r "^^^ ^'^^^ ^®"^ ^^°'"^* ^^'^3^ ^^ ^^"l^n an^ vegetable albumen; 76-459 of starch; 7-198 of sugar, gum, and extractive; 0-807 of husky matter. It is difficult to conceive how such great quantities of gluten, albumen, and extractive matter oould disappear m the sifting. The triticum spelta contains in 100 parts of the finest flour, 22-5 of a soft and humid gluten, mixed with vegetable albumen ; 74 of starch, and 5-5 of sugar. Here we have an excess of 2 parts in the iOO. Wheat furnishes very little ashes by incineration, not more than 0-15 per cent, of the weight; containing superphosphates of soda, lime, and masnesia. The object of baking is to combine the gluten and starch of the flour into a homo- geneous substance, and to excite such a vinous fermentative action, by means of its saccharine matter, as shall disengage abundance of carbonic acid gas in it for making an agreeable, soft, succulent, spongy, and easily digestible bread The two evils to be avoided in baking are hardness on the one hand, and pastiness on the other. Well-made bread is a chemical compound, in which the gluten and starch cannot be recognised or separated, as before, by a stream of water. When flour is kneaded into a dough, and spread into a cake, this cake, when baked, will be homy if it be thin, or if thick, will be tough and clammy; whence we see the value of that fermentative process, which generates thousands of little cells in the mass or crumb, each of them dry, yet tender and succulent, through the intimate combination of the moisture. By this constitution 11 becomes easily soluble in the juices of the stomach, or, in other words, light of diges- tion. It 18 moreover much less liable to turn sour than cakes made from unfermented dongh. Rye, which also forms a true spongy bread, though inferior to that of wheat, consists of similar ingredients; namely, 61-07 of starch; 9-48 of gluten ; 3-28 of vegetable albumen; 3-28 of uncrj^stallizable sugar; 11-09 of gum; 6-38 of vegetable fibre; the joss upon the 100 parts amounted to 5-62, includina: an acid whose nature the analvst, M. Emhof, did not determine. Rye flour contains also several salts, principally the phosphates of lime and magnesia. This kind of grain forms a dark-colored bread reckoned ver>' wholesome; comparatively little used in this country, but very much in France, Germany, and Belgium. Dough fermented with the aid either of leaven or yeast, contains little or none of the saccharine matter of the flour, but in its stead a certain portion, neariy half il^weight, of spirit, which imparts to it a vinous smell, and is volatilized in the oven; whence it might be condensed into a crude weak alcohol, on the plan of Mr. Hick*s patent, were it worth while. But the increased complexity of the baking apparatus will probably prove an effectual obstacle to the commercial success of this project, upon which already up- wards of £20,000 sterling have been squandered. That the sugar of the flour is the true element of the fermentation preposterously called panary, which dough undergoes, and that the starch and gluten have nothing to do with it, may be proved by decisive experiments. The vinous fermentation continues tm the whole sugar is decomposed, and no longer ; when, if the process be not checked by the heat of baking, the acetous fermentation will supervene. Therefore, if a little sugar be added to a flour which contains little or none, its dough will become susceptible 01 fermenting, with extrication of gas, so as to make spongy succulent bread. But since this sponginess is produced solely by the extrication of gas, and its expansion in the heat 01 the oven, any substance capable of emitting gas, or of being converted into it under these circumstances, will answer the same purpose. Were a solution of bicarbonate ol wnmonia obtained by exposing the common sesqui-carbonate in powder for a day to the air, incorporated with the dough, in the subsequent firing it will be converted into vapor, and in its extrication render the bread very porous. Nay, if water hfghly Impregnated with carbonic acid eas be used for kneading the dough, the resulting bread Vill be somewhat spongy. Could a light article of food be prepared in this way, then w the sugar would remam undecomposed, the bread would be so much the sweeter, and llie more nourishing. How far a change propitious to digestion takes place in the constitution of the starch and gluten, during the fermentative action of the dough, has •ot been hitherto ascertained by precise experiments. Medical practitioners, who 250 BREAD. \i » 11 t i derive an enormous revenue from dyspepsia, should take some pains to investigate lhi« subject. Dr. Colquhoun, in his able essay upon the art of makins; bread, has shown that its texture, when prepared by a sudden formation and disengagement of elastic fluid generated within the oven, differs remarkably from that of a loaf which has been made after the prepara- tory fermentation with yeast. Bread which has been raised with the common carbonate of ammonia, as used by the pastry-cooks, is porous no doubt, but not spongy with vesicu- lar spaces, like that made in the ordinary way. The former kind of bread never presents that air-cell stratification which is the boast of the Parisian baker, but which is almost un- known in London. I have found it, moreover, very difficult to expel by the oven the last portion of the ammonia, which gives both a tinge and a taste to the bread. I believe, however, that the bicarbonate would be nearly free from this objection, which operates so much against the sesqui-carbonate of the shops. In opposition to Mr. Edlin's account of the excellent quality of bread made by im- pregnating dough with carbonic acid gas,* Dr. Colquhoun adduces Vogel's experiments,* which show that such dough, when baked, after having been kept in a warm siti^ation during the usual time, afforded nothing better than a Aard cake, which had no resem- blance to common bread. Vogel further states, as illustrative of the general necessity of providing a sufficient supply of disengaged elastic fluid within the dough, before baking it at all, that when he made various attempts to form a well-raised vesicular loaf, within the oven, by mixing flour with carbonate of magnesia, or with zinc filings, and then kneading it into a paste by means of water, acidulated with sulphuric acid, he al- ways met with complete failure and disappointment. Dr. Colquhoun performed a series of well-devised experiments on this subject, which fully confirmed Vogel's results, and prove that a proper spongy bread cannot be made by the agency of either carbonic acid water, or of mixtures of sesqui-carbonate of soda, and tartaric acid. The bread proved doughy and dense in every case, though less so with the latter mixture than the former. No loaf bread can, indeed, be well made by any of these two extemporaneous systems, because they are inconsistent with the thorough kneading of the dough. It is this pro- cess which renders dough at once elastic enough to expand when carbonic acid gas is generated within it, and cohesive enough to confine the gas when it is generated. The whole gas of the loaf is disengaged in its interior by a continuous fermentation, a(\er all the processes of kneading have been finished ; for the loaf, after being kneaded, weighed out, and shaped, is set aside till it expands gradually to double its bulk, before it is put into the oven. But when a dough containing sesqui-carbonate of soda is mixed with one containing muriatic acid, in due proportions to form the just dose of culinary salt, the gas escapes during the necessary incorporation of the two, and the bread formed from it is dense and hard. Dr. Whiting has, however, made this old chemical process the subject of a new patent for baking bread. When the baker prepares his dough, he takes a portion of the water needed for the batch, having raised its temperature to from 70° to 100° F., dissolves a certain proporiiou of his salt in it, then adds the yeast, and a certain quantity of his flour. This mixture, called the sponge, is next covered up in the small kneading-trough, alongside of the large one, and let alone for setting in a warm situation. In about an hour, signs of vinous fermentation appear, by the swelling and heaving up of the sponge, in consequence of the generation of carbonic acid; and if it be of a semi-liquid con- sistence, large air bubbles will force their way to the surface, break, and disappear in rapid succession. But when the sponge has the consistence of thin dough, it confines the gas, becomes thereby equably and progressively inflated to double its original volume ; when no longer capable of containing the pent-up air, it bursts and subsides. This process of rising and falling alternately might be carried on during twenty-four hours, but the baker has learned by experience to guard against allowing full scope to the fer- mentative principle. He generally interferes after the first, or at furthest after the second or third dropping of the sponge ; for were he not to do so, the bread formed with such dough would be invariably found sour to the taste and the smeU. Therefore he adds at this stage to the sponge the reserved proportions of flour, salt, and water, which are requisite to make the dough of the desired consistence and size; and next mcor- porates the whole together by a long and laborious course of kneading. When this operation has been continued till the fermenting and the fresh dough have been intimately blended, and till the glutinous matter of both is worked into such union and consistence that the mass becomes so tough and elastic as to receive the smart pressure of the iiand without adhering to it, the kneading is suspended for some time. The dough is ftow abandoned to itself for a few hours, during which it continues in a state of active fermentation throughout its entire mass. Then it is subjected to a second but much leas laborious kneading, in order to distribute the generated gas as evenly as possibte '* Treatiw on the Art of Bread Making, p. 56. BREAD. 251 ao.onf its parts, so that they may all partake equally of the vesicular structure. Aftei this second kneading, the dough is weighed out into the portions suitable to the size of bread desired ; which are of course shaped into the proper forms, and once more set aside in a warm situation. The continuance of the fermentation soon disengages a fresh quantity of carbonic acid gas, and expands the lumps to about double their pristine volume. These are now ready for the oven, and when they finally quit it in the baked state, are about twice the size they were when they went in. The generation of the due quantity of gas should be complete before the lumps are transferred to the oven; because whenever they encounter its heat, the process of fermentation is arrested ; for it is only the previ- ously existing air which gets expanded throughout every part of the loaf, swells out its volume, and gives it the piled and vesicular texture. Thus the well-baked loaf is com- posed of an infinite number of cellules filled with carbonic acid gas, and apparently lined with a glutinous membrane of a silky softness. It is this which gives the light, elastic, porous constitution to bread. After sufltering the fermentative process to exhaust itself in a mass of dough, and the dough to be brought into that state in which the additk)n of neither yeast, nor starch, nor gluten will produce any effect in restoring that action, if we mix in 4 per cent, of saccha- rine matter, of any kind, with a little yeast, the process of fermentation will immediately re-commence, and pursue a course as active and lengthened as at first, and cease about the same period.* This experiment, taken in connexion with the facts formerly stated, proves that what was called panary fermentation, is nothing but the ancient and well-known process of the vinous fermentation of sugar, which generates alcohol. There seems to be but one ob- jection to the adoption of this theory. After the loaf is baked, there is found in its com- position nearly as much saccharine matter as existed in the flour before fermentation. M. Vogel stales that in the baked bread there remains 3'6 parts of sugar, out of the 5 parts which it orisinally contained. Thus, in 100 parts of loaf bread prepared with wheaten flour, distilled water, and yeast without the admixture of any common salt, he found the following ingredients : — Sugar ... 3.6 Torrefied or gummy starch - 18'0 Starch - - - 53-5 Gluten, combined with a little starch, 20*75 Exclusive of carbonic acid, muriate of lime, phosphate of lime, &.c. It must be borne in mind that in every loaf the process of fermentation has been pre- maturely checked by the baker's oven, and therefore the saccharine constituent can never be wholly decomposed. It seems certain, also, that by the action of gluten upon the starch in the early stage of the firing, a quantity of sugar will be formed by the saccha- rine fermentation ; which we have explained in treating of Beka. Several masses of dough were prepared by Dr. Colquhoun in which pure wheat starck was mixed with common flour, in various proportions. In some of the lumps thb starch had been gelatinized, with the minimum of hot water, before it was added to the flour. After introducing the usual dose of salt, the dough was thoroughly kneaded, set apart for the proper period, allowed to ferment in the accustomed way, and then baked in the oven. In outward appearance, increase of bulk, and vesicular texture, none of them differed materially from a common loaf, baked along with them for the sake of comparison ; except that when the starch considerably exceeded the proportion of flour in the lump, the loaf, though whiter, had not risen so well, being somewhat less vesicular. But, on tasting the bread of each loaf, those which contained most gelatinized starch were unex- pectedly found to be the sweetest. The other loaves, into which smaller quantities of the gelatinized starch had been introduced, or only some dry starch, had no sweetish taste whatever to distinguish them from ordinary bread. These facts seem to establish the conclusion, that the presence of gelatinous starch in bread put into the oven, is a means of tbrming a certain portion of saccharine matter within the loaf, during the bak- ing process. Now it is more than probable that gelatinized starch does exist, more or less, in all loaves which have been fermented by our usual methods, and hence a certain quantity of sugar will necessarily be generated at its expense, by the action of heaU Thus the diflSculty started by M. Vogel is sufficiently solved ; and there remains no doubt that, in the saccharine principle of flour, the fermentation has its origin and end, while dough is under fermentation. The source of the sourness which supervenes in bread, under careless or unskilful hands, had been formerly ascribed to each of all the constituents of flour ; to its gluten. Its starch, and its sugar; but erroneously, as we now see : for it is merely the result of the second fermentation which always succeeds the vinous, when pushed improperly too far. It has been universally taken for granted by authors, that the acid thus generated * Dr. CoIqoliMa, in Annals of Philoeopby for 1836, toI. zii. p. 171 \ } 252 BREAD. BREAD. 263 \U in dough is the acetic. But there appear good grounds to believe that it is frequently a less volatile acid, probably the lactic, particularly when the process has been tardy, from the imperfection of the yeast or the bad quality of the flour. The experiments of Vogel, Braconnot, and others, prove that the latter acid is generated very readily, and in considerable quantity during the spontaneous decomposition of a great many vegetable substances, when in a state of humidity. The presence of lactic acid would account for the curious fact, that the acidity of unbaked dough is much more perceptible to the taste than to the smell; while the sourness of the same piece of bread, after coming out of the oven, is, on the contrary, much more obvious to the olfactory organs than to the palate. But this is exactly what ought to happen, if the lactic acid contributes, in con- junction with the acetic, to produce the acescence of the dough. At the ordinary tem- perature of a bakehouse, the former acid, though very perceptible in the mouth, is not distinguishable by the nostrils; but as it is easily decomposed by heat, no sooner is it ex- posed to the high temperature of the oven, than it is resolved, in a great measure, into acetic acid,* and thus becomes more manifest to the sense of smell, and less to that of taste. This theory seems to explain satisfactorily all the phenomena accompanying the progress of fermentation in baker's dough, and also some of its results in the process of baking which do not easily admit of any other solution. There are extremely simple and effectual methods for enabling the baker to adopi measures either to prevent or correct the evil of acescence, and these are to neutralize the acid by the due exhibition of an alkali, such as soda ; or an alkatme earth, such as magnesia or chalk. And it affords a striking proof of how much the artisan has been accustomed to plod, uninquiring and uninformed, over the same ground, that a remedy so safe and so economical, should remain at this day unthought of and unemployed by most of the manufacturers of bread in the United Kingdom. The introduction of a small portion of carbonate of soda will rectify any occasional error in the result of the so called panary fermentation, and will, in fact, restore the dough to its pristine sweet- ness. The quantity of acetate of soda, which will be thus present in the bread, will be altogether inconsiderable ; and as it has no disagreeable taste, and is merely aperient to the bowels in a very mild degree, it can form no objection in the eye of the public police. The restoration of dough thus tainted with acid, and its conversion into pleasant and wholesome bread, has been suflSciently verified by experiment. But, according to Mr. Edmund Davy, carbonate of magnesia may be used with still greater advantage, as during the slow action of the acid upon it, the carbonic acid evolved serves to open up and lighten bread which would otherwise be dense and doughy from the indifferent quality of the flour. Here, however, the dangerous temptation lies with a sordid baker to use cheap or damaged flour, and to rectify the bread made of it by chemical agents, innocent in themselves, but injurious as masks of a bad raw material. When sour yeast must be used, as sometimes happens with the country bakers, or in private houses at a distance from beer breweries, there can be no harm, but, on the contrary, much propriety, in correcting its acidity, by the addition of as much carbonate of soda to it as will effect its neutralization, but nothing more. When sour yeast has been thus corrected, it has been found, in practice, to possess its fermentative power un- mipaired, and to be equally eflicacious with fresh formed yeast, in making good palata- ble loaves. We have seen that, in baking, about one fourth of the starch is converted into a matter possessing the properties of British gum (see Starch), and also that the gluten, though not decomposed, has its particles disunited, and is not so tough and adhesive as it is in the flour. This principle is also, as we have said, useful in cementing all the particles of the dough into a tenacious mass, capable of confining the elastic fluid gene- rated by the vinous fermentation of the sugar. Starch is the main constituent, the basil of nourishment in bread, as well as in all farinaceous articles of food. The albumen al- to of the wheat, being coagulated by the heat of the oven, contributes to the setting of the bread into a consistent elastic body. In the mills in the neighborhood of London, no less than seven distinct sorts of flout are ground out of one quantity of wheat. These are for one quarter — Fine flour Seconds - Fine middlings Coarse middlings Bran - Twenty-penny - Pollard - - 5 bushels 3 pecks. 2 1 0*5 3 3 2 14 2-5 *Ben«liaa. So that we have nearly a double bulk of flour, or 14 bushels and 2^ pecks from 8 busheb of wheat. In the sifting of the flour through the bolter, there is a fine white angular meal obtained called sharps, which forms the central part of the grain. It is consumed partly by the fine biscuit bakers. The bakers of this country were formerly bound by law to bake three kinds of bread, the wheateriy standard wheaten, and the household; marked respec- tively with a W, S W, and H, and if they omitted to make these marks on their bread they were liable to a penalty. The size of the loaves were usually peck, half-peck, quartern, and half-quartern ; the weights of which, within 48 hours of their being baked, should have been respectively 17 lbs. 6 oz. ; 8 lbs. 11 oz. ; 4 lbs. 5 oz. 8 dr. ; and 4 lbs. 2 oz. 14 dr. In general they weigh about one seventh more before they enter the oven, or they lose one seventh of their weight in baking. The French bread loses fully one sixth in the oven, owing chiefly to its more oblong thin shape, as compared to the cubical shape of the English bread. But this loss of weight is very variable, being de- pendant upon the quality of the wheaten flour, and the circumstances of baking. The present law in England defines the quartern loaf at 4 lbs., and subjects the baker to a penally if the bread be one ounce lighter than the standard. Hence it leaves the baker, in self-defence, to leave it in rather a damp and doughy state. But there is much light bread sold in London. I have met with quartern loaves of 3 lbs. 10 oz. A sack of flour weighing 280 lbs. was presumed by the framers of our former parliamentary acts, for the assize of bread, to be capable of being baked into 80 loaves. If this proportion had been correct, one fifth part of our quartern loaf must consist of water and salt, and four fifths of flour. But in general, of good wheaten flour, three parts will take up one part of water ; so that the sack of flour should have turned out, and actually did turn out, more than 80 loaves. At present with 4 lb. bread it may well yield 92 loaves. The following statement of the system of bakiag at Paris, I received in 1835 from a very competent judge of the business. 1,000 kilogrammes of wheat=5 quarters English, cost 200 fr., and yield 800 kilos, of flour of the best white quality, equivalent to 5J- sacks French. Hence the sack of flour costs 40 francs at the mill, and including the carriage to Paris, it costs 45 or 46 francs. The profit of the flour dealer is about 3| francs, and the sale price becomes from 43 to 50 francs. Bread manufactured from the above, /^ J » 1 /. £ s. d, £ 9, d. One day's work of an ordinary baker, who makes four batches in a day, consists of 3 sacks at 50 francs, or 21. sterling each Salt2f lbs. at2rf. perlb . Yeast or leaven 3 lbs. at 5(f . - Total cost of materials ...... Expenses of Baking. Three workmen at different rates of wages, 15 francs - Fire-wood 0, as the charcoal produced pays for it - General expenses, such as rent, taxes, interest of capital, &.c. For this sum 315 loaves are made, being 105 for every sack of flour weighing 156-66 kilos, or 344# lbs. avoird. One loaf contains therefore ^\^^^ = 3-282 lbs., and as 100 lbs. of flour in Parisian baking are reckoned to produce 127 lbs. of bread, each loaf will weigh 4-168 lbs., avoird., and will cost 7/. 5*. 8Jd. divided by 315 = 5^. very nearly. The value of 315 loaves at the sale price of Qd. will be----... 6 1 3 6 1 8i 12 12 == 1 4 1 4 7 5 Si 7 17 6 Upon this day's work the clear profit is therefore - - 11 61 A new baking establishment has been recently formed at the Royal Clarence VicJualUng Estabhshment at Weevil, near Portsmouth, upon a scale of magnitude near- ly suflicient to supply the whole royal navy with biscuits, and that of a very superior description. The following account of it is taken from the United Service Journal. It havmg been discovered that the flour supplied to government by contract, had in many instances been most shamefully adulterated, the com is ground at mills comprised Within the establishment, by which means the introduction of improper ingredients is prevented, and precisely the proportion of bran which is requisite in the composition of good sea-biscuit is retained, and no more. The flour-mill is furnished with ten pairs of 254 BREAD. BREAD. 355 I hi :';i!f \n rtones, by which 40 bushels ol flour may be ground and dressed ready for baking, in an hour. The baking establishment consists of 9 ovens, each 13 feet long by 11 feet \vide, and 17| inches in height. These are each heated by separate furnaces, so constructed that a blast of hot air and fire sweeps ihrough them, and gives to the interior the requisite dose of heat in an incredible short space of time. The first operation in making the biscuits consists in mixing the flour, or rather meal and water ; 13 gallons of water are first introduced into a trough, and then a sack of the meal, weighing 280 lbs. When the whole has been poured in by a channel communicating with an upper room, a bell rings, and the trough is closed. An apparatus consisting of two sets of what are called knives, each set ten in number, are then made to revolve amongst the flour and water by means of machinery. This mixing operation lasts one minute and a half, during which time the double set of knives or stirrers makes twenty-six revolutions. The next process is to cast the lumps of dough under what are called the breaking-rollers, — huge cylinders of iron, weighing 14 cwt. each, and moved horizontally by the machinery along stout tables. The dough is thus formed into large rude masses 6 feet long by 3 feet broad, and several inches thick. At this stage of the business, the kneading is still very imperfect, and traces of dry flour may still be detected. These great masses of dou^h are now drawn out, and cut into a number of smaller masses about a foe t and a half long by a foot wide, and again thrust under the rollers, which is repeated until the mixture is so complete that not the slightest trace of any inequahry is discoverable in any part of the mass. It should have been stated that two workmen stand one at each side of the rollers, and as the dough is flattened out they fold it up, or double one part upon another, so that the roller at its next passage squeezes these parts together, and forces them to mix. The dough is next cut into small portions, and being placed upon large flat boards, is, by the agency of machinery, conveyed from the centre to the extremity of the baking-room. Here it is received by a workman, who places it under what is called the sheet roller, but which, for size, color, and thickness, more nearly resembles a blanket. The kneading is thus complete, and the dough only requires to be cut into biscuits before it is committed to the oven. The cutting is efiected by what is called the cutting-plate, consisting of a net-work of 52 sharp-edged hexagonal frames, each as large as a biscuit. This frame is moved slowly up and down by machinery, and the workman, watching his opportunity, slides under it the above-described blanket of dough, which is about the size of a leaf of a dining-table ; and the cutting-frame in its descent indents the sheet, but does not actually cut it through, but leaves sufficient substance to enable the workman at the mouth of the oven to jerk the whole mass of biscuits unbroken into it. The dough is prevented sticking to the cutting-frame by the following ingenious device : between each of the cutter-frames is a small flat open frame, moveable up and down, and loaded with an iron ball, weighing several ounces. When the great frame comes down upon the dough, and cuts out 52 biscuits, each of these minor frames yields to the pressure, and is raised up ; but as soon as the great frame rises, the weight of the balls, acting upon the little frames, thrusts the whole blanket ofi", and allows the workmen to pull it out. One quarter of an ho\ir is suflicient .t) bake the biscuit, which is afterwards placed for three days in a drying room, heated to 85° or 90", which completes the process." The following statement of the per- formance of the machinery is taken from actual experiment ; in 116 days, during 68 of which the work was continued for only 7| hours ; and during 48, for only 5f hours each day, in all 769 working hours, equal to 77 days of 10 hours each ; the following quantity of biscuit was baked in the 9 ovens, viz. : 12,307 cwt. = 1,378,400 lbs. The wages of the men employed in baking this quantity amounted to 273/. 10*. 9|(f. ; if it bad been made by hand, the wages would have been 933Z. 9s. lOd. ; saving in the wages cf labor, 659/. Is. O^d. In this, is not included any part of the interest of the sum laid out upon the machine, or expended in keeping it in order. But in a very few years, at such an immense rate of saving, the cost of the engine and other machinery will be repaid. This admirable apparatus is the invention of T. T. Grant, Esq., storekeeper of the Royal Clarence Victualling Establishment, who, we believe, has been properly rewarded, by a grant of 2,000/. from government. The labor of incorporating the ingredients of bread, viz., flour, water, and salt, or kneading dough, is so great as to have led to the contrivance of various mechanical modes of producing the same eflect. One of the most ingenious is that for which a patent was obtained in August, 1830, by Mr. Edwin Clayton. It consists of a rotatory kneading trough, or rather barrel, mounted in bearings with a hollow axle, and of an interior frame of cast iron made to revolve by a solid axle which passes through the hollow one ; in the frame there are cutters diagonally placed for kneading the dough. The revolving frame and its barrel are made to turn in contrary directions, so as greatly to save time and equalise the operation. This double action represents kneading by the two hands, in which the dough is inverted from time to time, torn asunder, and reunited in every ditferent form. The mechanism will be readily understood from the following descriptioiu Fig. 190 exhibits a front elevation of a rotatory kneading trough, constructed according to improvementii specified by the patentee, the barrel being shown in section ; a is the barrel, into which the several ingredients, consisting of flour, water, and yeast, are put, which barrel is mounted in the frame-work b, with hollow axles c and d, which hoUow axles turn in suitable bearings at « ; / is the revolving frame which is mounted in the interior of the barrel a, by axles g and h. The ends of this revolving frame are fast- ened, or braced together by means of the oblique cutters or braces i, which act upon the dough when the machine is put in motion, and thus cause the operation of kneading. Either the barrel may be made to revolve without the rotatory frame, or the rotatory frame without the barrel, or both may be made to revolve together, but in opposite ways. These several motions may be obtained by means of the gear-work, shown at k, L and m, as will be presently described. If it be desired to have the revolving motion of the barrel and rotatory frame together, but in contrary directions, that motion may be obtained by fastening the hollow axle of the wheel n?, by means of a screw «, to the axle h, of the rotatory frame /, tight, so as they wiU revolve together, the other wheels k and / being used for the purjiose of re- versing the motion of the barrel. It wiU then be found that by turning the handle o, the two motions will be obtained. F\^^^^^^^^^^^ to put the rotatory frame /, only, into motion, that action will be ob- tamed by loosening tne screw n, upon the axle of the wheel w, when it will be found that the axle h will be made to revolve freely by means of the winch o, without giving motion to the wheels /c, /, and m, and thus the barrel will remain stationary. If the rotatory acUon of the barrel be wanted, it will be obtained by turning the handle p, at the reverse end of the machine, which, although it puts the gear at the opposite end of the barrel into motion, yet as the hollow axle of the wheel m is not fastened to the axle h. by the screw n, these wheels will revolve without carrying round the frame /. M. Kuhhnann, Professor of Chemistry at Lille, having been called upon several times by the courts of justice to examine by chemical processes bread suspected of containing substances injurious to health, collected some interesting facts upon the subject, which were published under the direction of the central council of salubrity of the department du Nord. For some time public attention had been drawn to an odious fraud committed by a great many bakers in the ftorth of France and in Belgium — the introduction of a certain quantity of sulphate of copper into their bread. WJicn the flour was made from bad gram this adulteration was very generally practised, as was proved by many convictions and confessions of the guilty persons. When the dough does not rise well in the fer- mentation (/6 pain pousse plat), this inconvenience was found to be obviated by the ad- diUon of blue vitriol, which was supposed also to cause the flour to retain more water. The quantity of blue water added is extremely small, and it is never done in presence of strangers, because it is reckoned a valuable secret. It occasions no economy of yeast, but rather the reverse. In a litre (about a quart) of water, an ounce of sulphate of copper IS dissolved ; and of this solution a wine-glass full is mixed with the water neces- sary for 50 quartern or 4 pound loaves. M. Kuhlmann justly observes, that there can be no safety whatever to the public when such a practice is permitted, because ignorance and avarice are always apt to increase the quantity of the poisonous water. In analyses made by him and his colleagues, portions of bread were several times found so impregnated with the above salt that they had ac- quired a blue color, and presented occasionally even small crystals of the sulphate. By acting on the poisoned bread with distilled water, and testing the water with ferro-cya- nate (prussiate) of potash, the reddish brown precipitate or tint characteristic of copper Will appear even with small quantities. Should the noxious impregnation be still more nunvte, the bread should be treated with a very dilute nitric acid, either directly or after incineration m a platinum capsule, and the solution, when concentrated by evaporation, •ftould bo tested by the ferro-cyanate of potash. In this way, a one seventy thousandth part of sulphate of copper may be detected. 256 BREAD. BREAD. I i m I ] M. Kuhlmaia deduces, from a series of experiments on baking with various small quantities of sulphate of copper, that this salt exercises an extremely energetic action uix)n the fermentation and rising of the dough, even when not above one seventy thou- sandth part of the weight of the bread is employed ; or one grain of sulphate for ten pounds of bread. The proportion of the salt which makes the bread rise best is one twenty thou- sandth, or one grain in three pounds of bread. If much more of the sulphate be added, the bread becomes moist, less white, and acquires a peculiar disagreeable smell like that of leaveh. The increase of weight by increased moisture may amount to one sixteenth without the bread appearing softer, in consequence of the solidifying quality of the cop- per ; for the acid does not seem to have any influence ; as neither sulphate of soda, sul- phate of iron, nor sulphuric acid have any analogous power. Alum operates like blue vitriol on bread, but larger quantities of it are required. It keeps watery and raises welU to use the bakers' terms. When alum is present in bread it may be detected by treating the bread with Jistilled water, filtering the water first through calico, and next through filtering paper, till it be- comes clear ; then dividing it into two portions, and into the one pouring a few drops of nitrate or muriate of barytes, and into the other a few drops of water of ammonia. In the former a heavy white precipitate indicating sulphuric acid will appear, and in the latter a light precipitate of alumina, redissolubic by a few drops of solution of caustie potash. When chalk or Paris plaster is used to sophisticate flour, they may be best detected by incinerating the bread made of it, and examining the ashes with nitric acid, which wiU dissolve the chalk with effervescence, and the Paris plaster without. In both cases the calcareous matter may be demonstrated in the solution, by oxalic acid, or better by oxa- late of ammonia. In baking puff-paste the dough is first kneaded along with a certain quantity of butter, then rolled out into a thin layer, which is coaled over with butter, and folded face-wise many times together, the upper and under surfaces being made to correspond. This stratified mass is again rolled out into a thin layer, its surface is besmeared with butter, and then it is folded face-wise as before. When this process is repeated ten or a dozen times, the dough will consist of many hundred parallel laminae, with butter interposed between each pair of plates. When a moderately thick mass of this is put into the oven, the elastic vapor disengaged from the water and the butter, diffuses itself between each of the thin laminae, and causes them to swell into what is properly called puff-paste, be- ing an assemblage of thin membranes, each dense in itself, but more or less distinct from the other, and therefore forming apparently, but not really, light bread. One of the most curious branches of the baker's craft is the manufacture of ginger- bread, which contains such a proportion of molasses, that it cannot be fermented b> means of yeast. Its ingredients are flour, molasses or treacle, butter, common potashes, and alum. After the butter is melted, and the potashes and alum are dissolved in a little hot water, these three ingredients, along with the treacle, are poured among the flour, which is to form the body of the bread. The whole is then incorporated by mixture and kneading into a stiff dough. Of these five constituents the alum is thought to be the least essential, although it makes the bread lighter and crisper, and renders the process more rapid ; for gingerbread dough reqftres to stand over several days, sometimes 8 or 10, before it acquires that state of porosity which qualifies it for the oven. The action of the treacle and alum on the potashes in evolving carbonic acid, seems to be the gasefying principle of gingerbread ; for if ihe carbonate of potash is withheld from the mixture, the bread, when baked, resembles in hardness a piece of wood. Treacle is always acidulous. Carbonate of magnesia and soda may be used as suIk stitutes for the potashes. Dr. Colquhoun has found that carbonate of magnesia and tartaric acid may replace the potashes and the alum with great advantage, affording a gingerbread fully more agreeable to the taste, and much more wholesome than the common kind, which contains a notable quantity of potashes. His proportions are one pound of flour, a quarter of an ounce of carbonate of magnesia, and one eighth of an ounce of tartaric acid ; in addition to the treacle, butter, and aromatics, as at present used. The acid and alkaline earth must be well diffused through the whole dough. The magnesia should, in fact, be first of all mixed with the flour. Pour the melted butter, the treacle, and the acid dissolved in a liitle water all at once among the flour, and knead into a consistent dough, which being set aside for half an hour or an hour will be ready for the oven, and should never be kept unbaked more than 2 or 3 hoars. The following more complete recipe is given by Dr. Colquhoun, for making thin ginger- bread cakes : — Flour 1 lb. Treacle 0| Raw sugar o| 257 Butter 2 ox. Carbon, magnesia Of Tartaric acid 0| Ginger Cinnamon Nutmeg 1 This compound has rather more butter than common thin gingerbread. I shall here insert a passage from my Dictionary of Chemistry, as published in 1821 1 as it may prove interesting to many of my present readers. « Under Process of Baking, in the Supplement to the Encyclopedia Britannica, we have the followmg statement :— ' An ounce of alum is then dissolved over the fire in a tin pot, and the solution poured into a large tub, caDed by the bakers the seasoning- tub. Four pounds and a half of salt are likewise put into the tub, and a pailful of hot water.'— Foo^ note on this passage.—* In London, where the goodness of bread is esti- mated ennrely by its whiteness, it is usual with those bakers who employ flour of an in- ferior quality, to add as much alum as common salt to the dough ; or, in other words, the quantity of salt added is dim.nished one half, and the deficiency supplied by an equal weight of alum. This improves the look of the bread very much, rendering' it much whiter and firmer.' " ^ In a passage which we shall presently quote, our author represents the bakers of London in a conspiracy to supply the citizens with bad bread. We may hence infer that the full allowance he assigns of 2^ pounds of alum for every 2^ pounds of salt, will be adopted in converting the sack of flour into loaves. But as a sack of flour weighs 280 pounds, and furnishes on an average 80 quartern loaves, we have 2i pounds divided bv on «- 15750 grrains m-r • /• ^t .. . . *"» ^^ ~m = ^^' grains, for the quantity present, by this writer, in a London quartern loaf. Yet in the very same page (39th of vol. ii.) we have the following passage : " Alum is not added by all bakers. The writer of this article has been assured by several bakers of respectability, both in Edinburgh and Glasgow, on whose testimony he relies, and who made excellent bread, that they never employed anv alum. The rea- son for adding it given by the London bakers is, that it renders the bread whiter, and en- ables them to separate readily the loaves from each other. This addition has been aUeged by medical men, and is considered by the community at large, as injurious to the health, by occasioning constipation. But if we consider the small quantity of this salt added by the baker, not quite 5^ grains to a quartern loaf, we will not readily admit these allega- tions. Suppose an individual to eat the seventh part of a quartern loaf a day, he would only swallow eight tenths of a grain of alum, or, in reality, not quite so much as half a grain ; for one half of this salt consists of water. It seems absurd to suppose that half a grain of alum, swallowed at different times during the course of a day, should occasion constipation." Is it not more absurd to state 2\ pounds or 36 ounces, as the alum adul- teration of a sack of flour by the London bakers, and within a few periods to reduce the adulteration to one ounce ? That this voluntary abstraction of f f of the alum, and substitution of superior and more expensive flour, is not expected by him from the London bakers, is sufliciently evi- dent from the following story. It would appear that one of his friends had invented a new yeast for fermenting dough, by mixing a quart of beer barm with a paste made of ten pounds of flour and two gallons of boiling water, and keeping this mixture warm for MX or eight hours. "Yeast made in this way," says he, « answers the purposes of the baker much better than brewers' yeast, because it is clearer, and free from the hop mixture which sometimes mjures the yeast of the brewer. Some years ago the bakers of London, sensible of the superiority of this artificial yeast, invited a company of manufacturers from Glasgow to establish a manufactory of it in London, and promised to use no other. About 5,000/. accordingly was laid out on buildings and materials, and the manufactory was begun on a considerable scale. The ale-brewers, finding their yeast, for which thev had drawn a gaod price, lie heavy on their hands, invited aZZ the journeymen bakers to 'their cellars, gave them their full of ale, and promised to regale them in that manner every day, provided they would force their masters to take all their yeast from the ale-brewers. The journeymen accordingly declared, in a body, that they would work no more for their masters unless they gave up taking any more yeast from the manufactory. The masters were obliged to comply ; the new manufactory was stopped, and the inhabitants of Lon- don were obliged to continue to eat worse bread, because it was the interest of the ale- brewers to sell the yeast. Such is the influence of journeymen bakers in the metropolii of England!" This doleful diatribe seems rather extravagant; for surely beer yeast can derive nothing noxious to a porter drinking people, from a slight impregnation of hops ; while It must form probably a more energetic ferment than the fermented paste of the new eompany, which at any rate could be prepared in six or eight hours by any baker wlw ;1J1. liiti; t I 11 ;! 258 BREAD. BREAD. 3fi» found it to ansTver his purpose of making a pleasant eating bread. But it is a very serioiii thin? for a lady or gentleman of sedentary habits, or infirm constitution, to have their di- gestfve process daily vitiated by daroi^ed flour, whitened with 197 grains of alum pei quartern loaf. Acidity of stomach, indigestion, flatulence, headaches, palpitation, costiye- ness and urinary calculi may be the probable consequences of the habitual introduction of so much acidulous and acescent matter. I have made many experiments upon bread, and have found the proportion of alum very variable. Its quantity seems to be proportional to the badness of the flour; and hence when the best flour is used no alum need be introduced. That alum is not necessary for giving bread its utmost beauty, sponginess, and agreeableness of taste, is undoubted ; since the bread baked at a very extensive establishment in Glasgow, in which about 20 tons of flour were regularly converted into loaves in the course of a week, united every quality of appearance with an absolute freedom from that acido-astringent drug. Six pounds of salt were used for every sack of flour ; which, from its good quality, generally afibrdcd 83 or 84 quartern loaves of the legal weight of four pounds five ounces and a half each. The loaves lost nine ounces in the oven. Every baker ought to be able to analyze his flour. He may proceed as follows : — A duc- tile paste is to be made with a pound of the flour and a sufficient quantity of water, and left at rest for an hour ; then having tied across a bowl a piece of silken sieve-stufl", a little below the surface of the water in the bowl, the paste is to be laid upon the sieve on a level with the water, and kneaded tenderly with the hand, so as merely to wash the Starchy particles out of it. This portion of the flour gets immediately diffused through the water, some of the other constituents dissolve, and the gluten alone remains upon the filter. The water must be several times renewed till it ceases to become milky. The last washings of the gluten are made out of the sieve. The whole of the turbid washings are to be put into a tall conical glass or stoneware vessel, and allowed to remain at rest, in a cool place, till they deposite the starch. The clear supernatant liquor is then decanted off. The deposite consists of starch, with a little gluten. It must be washed till the water settles over it quite clear, and then it is to be dried. n t « . The filtered waters being evaporated at a boiling heat, discover flocks floating through them, which have been supposed by some to be albumen, and by others gluten. At last, phosphate of lime precipitates. When the residuum has assumed a sirupy consistence in the cold, it is to be mixed with alcohol, in order to dissolve out its sugar. Cold water bein" added to what remains, effects a solution of the mucUage, and leaves the insoluble azotized matter with the pLospnate of lime. By this mode of analysis a minute portion of resin may remain in the gluten and in the washin? water ; the gluten retains also a small proportion of a fixed oil, and a volatile nrincipfe, which may be removed by alcohol. If we wish to procure the resin alone, we inust first of all treat the flour, well dried, with alcohol. When corn flour, poor in gluten, is to be analyzed, the dough must be enclosed in a linen bag, kneaded with water, and washed in that stale. In analyzing barley -meal by the above process, hordeine, mixed with common starch, is ©btained : they may be separated by boiling water, which dissolves the starch, and leavei Uie hordeine under the aspect of saw-dust. Fig. 191 is the plan of a London baker's oven, fired with coal fuel. Fig. 192 is the longitudinal section. a the body of the oven ; b, the door ; c, the fire-grate and furnace ; d, the smoke flue*- e the flue above the door, to carry off the steam and hot air, when taking out the break;'/, recess below the door, for receiving the dust; g, damper plate to shut off the 'flue ; h, damper plate to shut off smoke flue, aAer the oven has come to iu proper the fire-place c below the fur heat ; t, a small ircd pan over for heating water; k, ash-pit nace. Fig. 193 is the front view ; the same letters re- fer to the same objects in all the figures. The flame and burnt air of the fire at c, sweep along the bottom of the oven by the right hand side, are reflected from the back to the left hand side, and thence escape by the flue d ; (see plan fig. 193.) Whenever the oven has acquired the proper degree of heat, the fire is withdrawn, the flues are closed by the damper plates, and the lumps of fermented dough are introduced. I believe it may be safely asserted that the art of baking bread, pastry, and confec- tionery, is carried in Paris to a pitch of refinement which it has never reached in London. I have never seen here any bread which, in flavour, colour and texture, rivalled the French pain de gruau. In fact, our corn monopoly laws, till they were of late happil^r repealed, prevented us from getting the proper wheat for preparing, at a moderate price, the genuine semoule out of which that bread is baked. Hence, the plebeian bourgeoii can daily grace his table with a more beautiful piece of bread than the most aflSuent English nobleman. The French process of baking has been recently described, with some minuteness, by their distinguished chemist, M. Dumas* and it merits to be known in this country. At each operation, the workman (petrisseur) pours into the kneading trough the residuary leaven of a former kneading, adding the proportion of water which practice enjoins, and diffuses the leaven through it with his hands. He then introduces into the liquid mass the quantity of flour destined to form the sponge {pate). This flour is let down from a chamber above, through a linen hose {manche), which may be shut by folding it up at the end. The workman now introduces the rest of the flour by degrees, diffusing and mingling it, in a direction from the right to the left end of the trough. When he has thus treated the whole mass successively, he repeats the same manipulation from left to right These operations require no little art for their dextrous performance ; hence they have the proper name assigned respectively to each, of /ravage and contre- ^roioge. The workman next subjects the dough to three different kinds of movement, m the kneading process. He malaxates it; that is, works it with his hands and fingers, in order to mix very exactly its component parts, while he adds the requisite quantity of flour. He divides it into six or seven lumps (pdtons), each of which he works successively in the same manner. Then he seizes portions of each, to draw them out, taking only as much as he can readily grasp in his hands. When he has thus kneaded the different lumps, he unites them into one mass, which he extends and folds repeatedly back upon itself He then lifts up the whole at several times, and dashes it forcibly against the kneading trough, collecting it finally at its left end. The object of these operations is to effect an intimate mixture of the flour, the water, and the leaven. No dry powdery spots called marrons, should be left in any part of the dougli. The kueader has now completed his work ; and after leaving the dough for some time at rest^ he turns it upside down. He lays the lumps, of a proper weight, upon a table, rolls them out^ and dusts them with a little flour. He next turns over each lump, and puts it in its panneton, where he leaves it to swell. If the flour be of good quality, the dough be well made, and the temperature be suitable, the lumps will swell much and uniformly. If after the surface has risen, it falls to a considerable extenty the flour must be bad, or it must contain other substances, as potato starch, bean meal, . mu n The theory of panijication (bread-baking) is easy of comprehension. The flour owes this valuable quality to the gluten, which it contains in greater abundance than any of the other cerealia (kinds of corn). This substance does not constitute, as had been heretofore imagined, the membranes of the tissue of the perisperm of the wheat; but is enclosed in cells of that tissue under the epidermic coats, even to the centre of the grain. In this respect the gluten lies in a situation analogous to that of the starch, and of most of the immediate principles of vegetables. The other immediate principles which play a part in panificaiion are particularly the starch and the sugar ; and they all operate as follows : — The diffusion of the flour through the water, hydrates the starch and dissolves the sugar, the albumen, and some other soluble matters. The kneading of the dough, by completing these reactions through a more intimate union, favors also the fermen- tation of the sugar, by bringing its particles into close contact with those of the leaven or yeast ; and the drawing out and malaxating the dough softens and stratifies it, introducing at the same time oxygen to aid the fermentation. The dough, when distributed and formed into loaves, is kept some time in a gentle warmth, in the folds of the cloth, pans, &c., a circumstance propitious to the development of their volume by fermentation. The dimensions of all the lumps of dough now gradually enlarge, from the disengagement of carbonic acid in the decomposition of the sugar ; which gas is imprisoned by the glutinous paste. Were these phenomena to continue too long, the dough would become too vesicular ; they must, therefore, be stopped at the proper point of sponginess, by placing the loaf lumps in the oven. Though this causes a sndden expansion of the enclosed gaseous globules, it puts an end to the fermentation, and to their growth ; as also evaporates a portion of the water. The fermentation of a small dose of sugar is, therefore, essential to true bread- baking ; but the quantity actually fermented is so small as to be almost inappreciable. It seems probable that in well-made dough the whole carbonic acid that is generated remains in it; amounting to one half the volume of the loaf itself at its baking tempera- ture, or 212°. It thence results that less than one hundredth part of the weight of the flour is all the sugar requisite to produce well-raised bread. What egregious folly was it, therefore, to mount the bakery in Chelsea, twelve years ago, at an expense of 20,000Z., for the purpose of catching the volatile spirits in their escape from the loaves in the oven — or, as it was vulgarly termed, " taking the gin out of the bread !" whereas it was nothing but taking the cash out of the pockets of the pseudo-chemical visionaries who swarm in this metropolis. The richness or nutritive powers of sound flour and also of bread are proportional to the quantity of gluten they contain. It is of great importance to determine this point, for both of these objects are of enormous value and consumption ; and it may be accom- plished most easily and exactly by digesting in a water-bath, at the temperature of 167* F., 1,000 grains of bread (or flour) with 1,000 grains of bruised barley-malt, in 5,000 grains, or in a little more than half a pint, of water. When this mixture ceases to take a blue color from iodine (that is, when all the starch is converted into soluble dextrine^ the gluten left unchanged may be collected on a filter cloth, washed, dried at a heat of 212^, and wei?hed. The color, texture, and taste of the gluten, ought also to be ex- amined, in forming a judgment of good flour, or bread. Independently of the skill of the baker, bread varies in quality according to the quantity of water and gluten it contains. A patent of German or French origin was obtained here a few years ago, for manufacturing loaf-bread by using thin boiW floor. paste instead of water for setting the sponge, that is, for the preliminary dough fermen- tation. By this artifice, 104 loaves of 4 lbs. each could be made out of a sack of flour, instead of 94, as in ordinary baking ; because the boiled paste gave a water-keeping faculty to the bread in that proportion. But this hijdrated bread was apt to spoil in warm weather, and became an unprofitable speculation to all concerned. Bread and flour are often adulterated in France with potato starch, but almost never, I believe, in this country. The sophistication is easily detected by the microscope, on account of the peculiar ovoid shape and the large size of the particles of the potato fecula. Horse-bean flour gives to wheaten bread a pinkish tint In spoiled flour (such as is too often used, partially at least, by our inferior bakers) the gluten some- times disappears altogether, and is replaced by ammoniacal salts.* In this case quick- lime separates ammonia from the flour without heat; in flour slightly damaged, or ground from damaged wheat, the gluten present is deprived of its elasticity, and is softer than in the natural state. On this account the gluten test of M. I3oland is valuable. It consists in putting some gluten into the bottom of a copper tube, and heating that tube in an oven, or in oil at a temperature of 284° F. The length to which the cylinder of gluten expands is proportional to and indicates its quality. It appears that a French sack of flour, which weighs 159 kilogrammes, aftbrds from 102 to 106 loaves of 2 kilogrammes each : and therefore, 159 . 62-0 :: 280 : 9 16; tliat is, if 169 kilogs. or lbs. afford 62 loaves of 4 kilogs. or lbs., 280 lbs., a sack English, should afford 9 1 6 loaves of 4 lbs. each; but our * Dumas, Chimie Appliquee, vi. 425. , \ 1 )l m r 264 BREWING. bakers usually make out 94 loaves, which are rated at 4 pounds, though they seldom weigh so mucn. The loaves of a baker in my neighbourhood, who supplied my family with bread for some time, were found on trial to be from 6 to 8 oz. deficient in weight : when challenged for this fraud, he had the effrontery to palliate it by alleging that all his neighbour bakers did the same. It must be borne in mind that a Paris loaf of 2 lbs. or 2 kilogs. contains more dry farina than a London loaf of like weight ; for it contains, from its form and texture, more crust. The crumb is to the crust in the Paris long loaves, as 25 to 75, or 1 to 3 ; in our quartern loaves it is as 18 or 20 to 100. M. Dumas gives the following Table : — Weight of a Sack of Flour. Number of Loaves. Weight of the Bread. Increase of Weight of Flour. Ratio of dry Flour — 1. to Bread. 159 Kilogs. 159 do. 169 do. 102 104 106 202 Kilogs. 208 do. 212 do. 1-283 1-300 1-333 1 : 1-60 Thus it would appear that the mean yield would correspond to 130 kilogs. of bread for 100 of the flour employed: and admitting that common flour contains 0-17 of water, the product would be equivalent to 150 of bread for 100 of flour absolutely dry. The whole loaf contains 66 per cent, of dry substance, and the crumb only 44. BRECCIA, an Italian term, used by mineralogists and architects to designate such compound stony masses, natural or artificial, as consist of hard rocky fragments of considerable size, united by a common cement. "When these masses are foi-med of small rounded pebbles, the conglomerate is called a pudding-stone, from a fancied resemblance to plum pudding. Concrete, now so much used for the foundation of large buildings, is a factitious breccia, or pudding-stone. See Concrete. BREWING. {Brasser, Fr. ; Brauen, GeroL) The art of making Beer, which see. The peculiar properties contained in wort, do not exist ready formed in malt, but are the result of the direct action of heat and water upon that substance. Hence it follows that the composition of beer-wort depends more upon the process of mashing than upon the malt employed, — for it would be quite practicable to obtain from 1 part of malt and 8 parts of barley, a wort precisely similar to that procured from 9 parts of pure malt alone. But, of course, this could not be done without modifying consi- derably the process of mashing ; and it happens, unfortunately, that the practice of the present day, amongst brewers, is to maintain, as closely as possible, one uniform system of mashing, whatever may be the nature or quality of the malt employed. Thus a difference in the malt is made to produce a difference in the wort, and all the energy and skill of the practical brewer are sometimes insuflScient to compensate for the alter- ations which this difi'erence induces in the subsequent working of the beer. With a regular and certain composition, as to the constituents of his wort, the operations of the brewer would assume a fixed and definite character, which, at present, they are very far indeed from possessing ; and by which he not unfrequently suffers the most severe pecuniary loss and mental anxiety. "With the exception of a trifling quantity of vege- table albumen, the only solid ingredients of beer-wort are dextrine and sugar; the latter of which ferments with great ease and rapidity, whilst the dextrine, though capable of fermentation, enters into the process only with difficulty, and requires, for its suocessful termination, not only much more yeast, but also a much higher temperature in the fermenting fat. At the same time, it is this very sluggishness in the fermentative quality of dextrine which is essential to the production of good beer ; for, with sugar alone, the fermentation cannot be checked at ordinary temperatures, until the full measure of its decomposition has taken place, and it has become either a vapid admixture of alcohol and water, or, by the absorption of oxygen, is resolved into vinegar. It is indeed a notorious fact, that beer made with sugar will not keep so well as that made from malt ; though, for rapid consumption, the use of sugar is, under some circumstances, to be commended, more especially on the small scale and in cold weather. The pecu- liarity of dextrine is, however, as we have stated, to undergo fermentation only with difficulty and by slow degrees ; hence its decomposition spreads over a long space of time, and, in very cold weather, amounts to nothing ; so that for months, or even years, after all the sugar of the wort has been destroyed, the evolution of carbonic acid gas from the still fermenting dextrine, keeps up a briskness and vitality in the beer ; and, by excluding oxygen, all chance of acidification is shut off. A perfect beer-wort should therefore have reference to the period of its consumption : if this be speedy and pressing, the proportion of sugar ought to be large ; if remote, the dextrine should greatly pre- dominate. Under the first condition, the attenuation would proceed quickly, and, provided the temperature of the fermenting vat was not allowed to exceed 78°, the beer would soon cleanse and become ripe and bright ; under the second, the attenuation in BREWING. 265 the vat would be slow and trifling, and require, perhaps, several years for its completion in the cask. Nevertheless, if the attenuation in the vat had gone on to the complete destruction of all the sugar, this kind of beer would prove in the end both the better and more healthy beverage of the two ; for by the mode of its formation the presence of senanthic ether or fusel oil is avoided. The importance therefore of placing in the hands of the brewer a means of determining the relative amounts of sugar and dextrine in his wort is sufficiently obvious. Now, this may be done in two ways ; either by ascertaining, in wort of a determinate strength, the proportion of the one or the other of these substances. The dextrine is easier of calculation than the sugar, in a rough or approximate way ; but the sugar can be determined with much more minute accuracy than the dextrine. Yet, in practice, the former plan is preferable, from its simplicity, as we shall proceed to show. I^ to a certain volume of strong wort (say of 30 lbs. per barrel), we add an equal amount of alcohol or spirits of wine, the whole of the dextrine will precipitate as a dense coagulum ; and by examining the bulk of this deposit in the tnbe, its weight may be inferred pretty nearly if the tube has been previously graduated so as to indicate, from actual experiment, the weight of the difterent measures of the coagulated dextrine. "With weaker wort, more alcohol must be used, and with a denser wort, less alcohol, — the relations of which to each other may easily be kept recorded on a small card or scale affixed to the tube. This instrument is very easy of application, and has been found extremely useful to more than one practical brewer of the present day ; and the accompanying record of brewing operations has reference to this mode of analysing wort. The determination of sugar in wort is best effected by boiling 100 grs. of it with about half a pint of the following solution, and collecting and weighing the red-coloured precipitate which ensues, — every three grains of which indicate one grain of grape-sugar in the wort. Grape-sugar Test Solution, Sulphate of copper in crystals . - - - 100 grains Bitartrate of potash - - - - - 200 do Carbonate of soda in crystals - - - - soo do Boiling water, one pint, or - - - - 8750 do First dissolve the sulphate of copper, then the bitartrate of potash, after which add the carbonate of soda, and filter if necessary. This solution is not affected when boiled with cane-sugar, dextrine, gum, or starch. We now proceed to lay before our readers the result of two brewings taken from one mash at two diflferent periods, and analyzed to determine their relative contents of dex- trine and sugar, according to the tube or alcohol process: — March 28th, 1851, proceeded to mash for experimental brewings ; weather clear and open ; thermometer outside at 51°, — in fei-menting room 68* ; difference between wet and dry bulb 5-750° ; barometer 89-4 inches. Composition of the malt : — Moisture 6-1 ; insoluble matter 27 ; extract 66-9. Quantity of malt employed 70 bushels; of water at 180° F., 700 gallons; made the mixture with a common mashing-oar, and finished in fifteen minutes. One hour afterwards, drew off 200 gallons of wort ; and three hours from commencing to mash, drew off 200 gallons more, — continuing the mash for table-beer-wort The first-drawn wort contained 7-5 parts of dextrine to 1 of sugar; the second, 6-3 parts of dextrine 2*2 of sugar; — their densities were, respectively, 30 and 36*5 lbs. per barrel. They were each boiled separately, with relative amount of hop, — the first having 30 and the second 36^^ lbs. added ; and the boiling in each case was kept up for three hours. At the end of this time both were cooled and diluted with water to a gravity of 27^ lbs. per barrel, and 250 gallons of each let down into separate fermenting-vats placed side by side ; after which, they both received three quarts of good yeast, — the temperature being at 68° F. Two hours afterwards, the following observations commenced : — No. 1. being the wort containing 7*6 pai-ts of dextrine to 1 of sugar, and No. 2. the wort having 6-3 of dextrine to 2-2 of sugar. 1851. March 28. 5 p, " " 10 p, M. P. M. ^«7« tf A* Ja* *• 6 P. M. V A* JA* 6 P. M. 2 P. M. 80. f VouL 81. ril 2. 2 p. M. 11. 2 p. M. 13. 2 P. M. No. 1. No action Light thin cream White head Fine white head Thick tough head - Tough brown head - Ferment well roused up Attenuation of No. 1. (Skimmed oflf yeast) 2M Temp. 67-5 67-5 70- IV 74- 76- 76- Deg. 8i 10- 16- 16-6 266 BREWING. No. 2. No action .... Fine white head . . - Thick yellow head - . - Fine tough brown head High roused up rocky head In rapid fermentation - - - Throws up much yeast (skimmed off yeast) Ditto of No. 2. ... m n n Deg 68- 10' - 1A' - 11' - 11' 76-6 76- 12-7 16-6 17-6 »».-.... 18-2 The temperature of both had now fallen to 69* F., though each had been roused re- peatedly ; the yeast was, therefore, again skimmed off, and the beer run into barrels, and filled up with reserved wort three times a day as it worked over. On April the 18th the barrels were closed, having then lost, by attenuation, — No. 1. 16'2 lbs., and No. 2. 19'6 lbs. Six weeks afterwards these ales were examined ; — No 1. was found muddy and unpleasant ; whilst No, 2. had a fine fragrant aroma, a brisk, lively appearance, and was perfectly bright. On January 2nd, 1852, the casks were again examined; No. 1. had now lost 17*9 lbs., and was bright, rich, and fine flavoured ; whilst N. 2., though bright and pleasant, had contracted a little acidity, and was becoming flat ; it had lost, in all, 21i lbs. Two similar experiments, made about the same time in another quarter, gave almost exactly the same results ; and, consequently, there can be little doubt that, where a quick sale and rapid consumption of beer can be ensured, the great object of the brewer should be to convert as much of the dextrine of his wort into sugar as is proportional to the rapidity of that consumption ; whereas, for beer intended to keep, the opposite practice should be followed. The conversion of any given amount of the dextrine wort into sugar may be effected either by keeping up the temperature of the mash-tun, and prolonging the operation of mashing: or, which is better and simpler, by merely preserving the wort for a few houra at a heat of 170' F., either in the underback or any other convenient vessel. We have found from experiment that a wort which when run out from the mash-tun had only 3 parts of sugar to 16 of dextrine, became by 10 hours' exposure to a heat of 165* con- verted almost altogether into sugar, — the proportions then being 17 '8 of sugar to 1'2 of dextrine. A very important part of the duty of a brewer should therefore be, first, the deter- mination of the relative amounts of dextrine and sugar required to suit the taste of his customers, or the circumstances of the market, and next, the continued careful examin- ation of his wort, so as to insure that these proportions are regularly maintained ; for by no other plan is it possible to insure that certamty of result, and uniformity of quality which are essential to the proper conducting of an expensive business like brewing. It seems to us that far too little attention has hitherto been given to the fluctuating quali- ties of beer-wort In warm weather, this wort should probably contain at least twice as much dextrine as in winter ; yet this is the very period when from the increased tem- perature of the air and materials, the largest quantity of sugar must be formed by those who mash upon a fixed and unvarying principle. llence the proneness of the wort to ferment violently in summer is still further increased by the presence of an extra pro- portion of sugar ; — whereas prudence would suggest, under such circumstances, a pre- dominance of dextrine, and seek to effect this purpose by a low temperature in the mash-tun, and by shortening the period of mashing. We are not, however, aware that this custom prevails, except in one or two solitary instances, in the north of England, where it is well appreciated. As a general rule, in the management of wort, more sugar is requisite where small quantities are brewed at a time, than where large opera- tions are conducted, for the loss of heat is relatively larger in small masses than in large ones; and, from what has been stated, it must be apparent, that, as the fermen- tation of dextrine is more easily checked by cold than that of sugar, the beer brewed in trifling quantities could not preserve a fermentative temperature, but would become chilled and dead from the excessive radiation of caloric, unless a principle existed in it capable of fermentation at the most ordinary temperatures of this country. I^ there- fore, beer-wort consisting chiefly of dextrine be fermented in very cold weather, or with an insufficiency of yeast, or if the temperature happen to rise too high, so as to destroy or impair the fermentative power of the yeast, then a dull languid action will ensue, accompanied by what has been called the viscous fermentation, and the beer becomes permanently ropy, and is spoiled. Although, clearly, it would be impossible to lay down any specific rule for the proper proportion of dextrine and sugar in beer-wort, yet there could be no difficulty in each BREWING. 267 brewer determining for himself^ and for the conditions of size, time of sale, time of year, and other contingencies, the requisite ratio to be established in his own ease ; and, as we have shown, nothing can be simpler than the means proposed for ascertaining the com- position of wort. The advance of the arts is gradually assuming a character which will no longer permit any manufacturer to neglect the assistance of science ; and those who first take advantage of the power of knowledge, will assuredly leave their fellow-labourers behind. From being an uncertain and hazardous operation, brewing must ere long become a fixed and definite principle based upon facts well understood, and capable of perpetual re- petition and reproduction at will. To sum up briefly the general details of ale brewing, we may state, that, for most kinds of ale, the attenuation in the first instance should be finished in from 6 to 21 days, according to the strength of the wort ; that this attenua- tion should approach to two-thirds of the whole weight ; and that after tunning and cleansing, the ale itself should weigh about one-fourth of the original gravity of the wort. Thus, if the fermenting tun be set with wort of 27 lbs., then the attenuation should bring it down to 9 or 10 lbs., and the subsequent operations produce an ale weighing from 6 to 7 lbs. When these conditions are fulfilled, without much extra trouble or attention, the ale is pretty certain to turn out well, though, in some localities, ale is never attenuated to more than one-half its original gravity; this kind of ale is, however, very apt to become sour in hot weather and ropy in cold. We will now proceed to describe the brewing of porter, which differs from that of ale both in the nature of the materials used and in the mode of finishing the ferment- ation. Porter owes its peculiar colour and flavour to burnt saccharine or starchy mat- ter ; and this was formerly obtained by burning sugar until it exhaled the odour called by French writers " caramel." At present, however, nothing but highly-torrefied malt is used ; and of this there are several kinds, as brown malt, imperial malt, and black malt ; all of which are used by some brewere, whilst others employ only the brown and black, and a few the black alone, for giving colour and flavour. The fermentative quality is saccharine, is, however, the same as that of ale, and is derived from pale or Amber malt. As a general rule, the ratio of the colouring and flavouring malts are to the saccharine, as about 1 to 5, or 1 to 4 ; but where black malt only is used, the pro- portion does not exceed 1 to 10. The employment of these burnt malts permits a singular act of injustice on the part of the Excise, as regards the drawback on exportation. By the Excise regulations, it is assumed that a quarter of malt will produce four barrels of ale brewed from wort of the sp. gr. 1054, or 19*4 lbs. per barrel; but, although this is hopeless even with pale malt, yet with an admixture of brown and black malt the assumption becomes absurd in the extreme. Admitting that, by good management, on the average, four barrels of wort, weighing 20 lbs., can be obtained from one quarter of fine pale malt, yet in the operations of cooling, fermenting, tunning, skimming, and cleansing, a loss of fully 10 per cent, occurs under the most vigilant superintendence ; and, taking the great bulk of our metropolitan breweries, it would be nearer the truth to estimate this loss at 12 per cent In plain words, 100 gallons of wort will not, by any management, produce more than about 88 gallons of saleable beer, though no allowance is made for this by the Excise ; and the brewer who has paid duty upon 100 gallons gets a drawback upon but 88. This, however, is the most favourable view of the case ; and we solicit atten- tion to the force with which the argument returns in the instance of porter. If a quarter of pale malt be assumed at 84 lbs. of saccharine strength, then such an admixture of brown and black malt as is usually employed by brewers of porter, will not give more than about 24 lbs. ; and as this constitutes at least one-fifth of the whole bulk used in porter brewing, we see that a quarter of such mixed malt can never give more than 70 lbs. ; that is to say, 80 parts of pale malt, mixed with 20 of brown and black, instead of giving at the rate of 84 lbs., as pale malt alone does, would give but 70 lbs., or produce a difference between the actual return and that taken for granted by the Ex- cise authorities, of no less than 166 per cent; to which, if we add the loss previously mentioned as arising from fermentation, yeast, - gressive formation of sugar. The results were as follows : — 2 hours after mashing 3 ditto ditto 4 ditto ditto 6 ditto ditto 6 ditto ditto 7 ditto ditto 8 ditto ditto 9 ditto ditto 10 ditto ditto 11 ditto ditto 12 ditto ditto Sugar. Dextrine 1*3 18-7 41 15*9 6*3 13*7 8- V 12- 9*2 10*8 10*7 9-3 12* 8- 13*3 6-7 14*5 5*5 15-7 4^3 16-9 31 ^ Hence, instead of three hours, which is the period commonly used for mashing, the distiller would be warranted in continuing this operation for twelve hours. In reality however, it is only the wort which requires this treatment ; for, after the third hour all the starch and nearly the whole of the hordeine have become soluble, and nothing but continued heat is required to complete the saccharification of the wort. The working of the mash-tun need not therefore be varied, as it will suffice to maintain the under- back for 6 or 8 hours at a temperature of 170°. The advantage of converting all the dextrine into sugar is not limited to the mere saving of material, or the production of more alcohol, for there is another and most important object gained. Sugar ferments more freely and at a lower temperature than dextrine, consequently the heat of the fermenting vat need never rise so high, nor require the large quantity of yeast now employed for the purpose of forcing a rapid and hot fermentation. Thus the tendency to generate fusel oil would be destroyed, as there is not the slightest doubt that the formation of this oil is due to an excess of temperature in the fermenting-vat^ P 270 BRICK. BRICK. 271 li and constantly bears a relation to the amount of dextrine in the wort ; for this, as mre have before stated, necessitates the employment of a higher fermenting heat than sugar, by which the elements of the decomposing materials take on new and unusual arrange- ments. The presence of fusel oil in spirit is a serious impediment to the distiller, and either retards the sale of his produce, or diminishes its value in the market. As usual, the Excise regulations interfere much with the progress of this, as of every other manufacture under fiscal superintendence. Careful to prevent fraud, they cripple industry, and seek, as it were, to secure the honesty of the labourer by cutting off his hand : — ignorant or careless, meanwhile, of the permanent mischief which they inflicts Yet, we know of no more fitting subject for fiscal burdens, than the manufacture of ardent spirits ; and had Excise interference been limited to this branch of industry, we should have deemed it a matter for congratulation, rather than otherwise. Neverthe- less, consistency is a kind of virtue in politics ; and we cannot imagine why the quasi superior, moral, and intellectual status of Ireland is continually tempted\o err, by a low duty of but 2«, Sd. per gallon, whilst nearly three times this amount is needed to repress the Dad habits of the people of England. The duty now charged is, for England 7«. lOdl, for Scotland 3«. Sd., and for Ireland 2«. 8ct per gallon of proof spirits : but on what principle this graduated scale of temptation to drunkenness has been eo fixed, we are qnite unable to conceive. To return, however, to the question of distillation, the duty «an be charged the distiller in any one of three ways, viz. according to the gravity of the wort he uses : the attenuation of that wort by fermentation ; or lastly, the actual quan- tity of spirit which he produces ; the latter being, of course, the only just mode of charge. The restrictions and penalties are excessive, as our courts of law too frequently testify ; *nd the notorious prevalence of smuggling seems to prove that the present rates of duty are too high, and offer a premium for fraud greater than the terror of a temporary im- prisonment The greatest improvement in modern times, as regards distillation, is that Drought about by the invention of the apparatus, now well known under the name of " Coffey's stilL" It would be foreign to our task to give a minute description of this contrivance here (see Still); its principle is similar to that of the "cascade chi- mique" of Clement Desormes. The wort, or other fluid to be distilled, is made to flow over a very extensive surface in contact with a current of steam passing in an opposite direction ; by which means the steam is condensed, and giving up its latent heat to the more volatile spirit, this latter is driven on into the condenser in a state of great purity ; whilst the residuary wort and the condensed steam flow out of the vessel from beneath in a continual stream, Mr. Coffey had many impediments to contend with, from the opposition of the Excise authorities, in his first attempt to introduce this in- genious invention into public use ; but prejudice and ignorance have at length given way, and the Coffey's still may be now seen in operation at almost every large distillery in the kingdom. After the distiller has paid duty on the spirit which he has manufac- tured, it is transmitted to the rectifier, whose premises must be at a considerable distance from the distillery, according to act of parliament. The business of the rectifier is to purify the spirit by separating its fusel oil ; and this he commonly effects through the agency of caustic potash. The impure spirit being mixed with a portion of potash, and carbonate of potash, is carefully distilled or rectified, until it ceases to possess any disagreeable odour, when it is again distilled in contact with certain aromatic substances, to give it the requisite qualities of the particular spirit or liquor desired. There is, how- ever, too much reason to fear that the necessary measures of purification are neglected in the case of common gin, — the defect being merely covered or concealed beneath more powerful odours. This practice cannot be too strongly reprobated; for experi- ments made purposely on dogs have convinced us that fusel oil is a highly poisonous Bubstance, and possesses acro-narcotic powere of no ordinary energy. Its removal from an article of universal consumption, like spirits, ought therefore to be deemed an im- portant subject for sanitary legislation, and not left to the casual skill or dubious honesty of any class of manufacturers whatever. There is more or less fusel oil in all the gin we have examined. BRICK. {Brique, Fr. ; Backsteine, ziegelsteine, Germ.) A solid, commonly rectan- gular, composed of clay hardened by heat, and intended for building purposes. The natural mixture of clay and sand, called loatn, as well as marl, which consists of lime and clay, with little or no sand, constitutes also a good material for making bricks. The poorer the marl is in lime, the worse adapted it is for agricultural purposes, and the better for the brick manufacturer, being less liable to fuse in his kiln. When a natural compound of silica and clay can be got nearly free from lime and magnesia, it forms a kind of bricks very refractory in the furnace, hence termed ^re-bricks. Such a material is the slate-clay, ichieferthon, of our coal measures, found abundantly, and of excellent quality, at Stourbridge, and in the neighbourhood of Newcastle and Glasgow. The Loudon brick-makers add to the clay about one-third of coal ashes obtained from the kitchen dust-holes ; so that when the bricks are put into the kiln, the quantity of coaly matter attached to their surface serves to economise fuel, and makes them less apt to shrink in the fire ; though they are less compact, and probably less durable than the bricks made in the coal districts of England. The general process of brick-making consists in digging up the clay in autumn ; exposing it, during the whole winter, to the frost, and the action of the air, turning it repeatedly, and working it with the spade ; breaking down the clay lumps in spring, throwing them into shallow pits, to be watered and soaked for several days. The next step is to temper the clay, which is generally done by the treading of men or oxen^ In the neighbourhood of London, however, this process is performed in a horse-milL The kneading of the clay is, in fact, the most laborious but indispensable part of the whole business ; and that on which, in a great measure, the quality of the bricks depends. All the stones, particularly the ferruginous, calcareous, and pyritous kinds, should be removed, and the clay worked into a homogeneous paste with as little water as possible. The earth, being sufficiently kneaded, is brought to the bench of the moulder, who works the clay into a mould made of wood or iron, and strikes off the superfluous matter. The bricks are next delivered from the mould, and ranged on the ground ; and when they have acquired sufficient firmness to bear handling, they are dressed with a knife, and staked or built up in long dwarf walls, thatched over, and left to dry. An able workman will make, by hand, 5000 bricks in a day. The different kinds of bricks made in England are principally place bricks, gray and red stocks, marl facing bricks, and cutting bricks. The place bricks and stocks are used in common walling. The marls are made in the neighbourhood of London, and used in the outside of buildings ; they are very beautiful bricks, of a fine j'ellow colour, hard, and well burnt, and, in every respect, superior to the stocks. The finest kind of marl and red bricks, called cutting bricks, are used in the arches over windows and doors, being rubbed to a centre, and gauged to a height In France attempts were long ago made to substitute animals and machines for the treading of men's feet in the clay kneading pit ; but it was found that their schemes could not replace, with advantage, human labour where it is so cheap, particularly for separating the stones and heterogeneous matter from the loam. The more it is worked, the denser, more uniform, and more durable, the bricks which are made of it A good French workman, in a day's labour of 12 or 13 hours, it has been said, is able to mould from 9000 to 10,000 bricks, 9 inches long, 4^ inches broad, and 2^ thick ; but he must nave good assistants under him. In many brickworks near Paris, screw-presies are aow used for consolidating the bricks and paving tiles in their moulds. M. Mollerat employed the hydraulic press for the purpose of condensing pulverized clay, which, after baking, formed beautiful bricks ; but the process was too tedious and costly. An ingenious contrivance for moulding bricks mechanically, is said to be employed near Washington, in America. This machine moulds 30,000 in a day's work of J2 hours, with the help of one horse, yoked to a gin wheel, and the bricks are so dry when discharged from their moulds, as to be ready for immediate burning. The machine is described, with figures, in the Bulletin de la Societe d^EncouragemeTtt for 1819, p. 361. See further on^ an account of our recent patents. Bricks, in this country, are generally baked either in a clamp or in a kiln. The latter is the preferable method, as less waste arises, less fuel is consumed, and the bricks are sooner burnt. The kiln is usually 13 feet long, by 10^ feet wide, and about 12 feet in height. The walls are one foot two inches thick, carried up a little out of the perpendicular, inclining towards each other at the top. The bricks are placed on flat arches, having holes left in them resembling lattice-work; the kiln is then covered with pieces of tiles and bricks, and some wood put in, to dry them with a gentle fire. This continues two or three days before they are ready for burning, which is known by the smoke turning from a darkish color to transparent. The mouth or mouths of the kiln are now dammed up with a shinlog, which consists of pieces of bricks piled one upon another, and closed with wet brick earth, leaving above it just room sufficient to receive a fagot. The fagots are made of furze, heath, brake, fern, &c., and the kiln is supplied with these until its arches look white, and the fire appears at the top ; upon which the fire is slackened for an hour, and the kiln allowed graduedly to cool. This heating and cooling is repeated until the bricks be thoroughly burnt, which is generally done in 48 hours. One of these kilns will hold about 20,000 bricks. Clamps are also in common use. They are made of the bricks themselves, and generally of an oblong form. The foundation is laid with place brick, or the driest of those just made, and then the bricks to be burnt are built up, tier upon tier, as high as the clamp is meant to be, with two or three inches of breeze or cinders strewed between each layer of bricks, and the whole covered with a thick stratum of breeze. The fire- place is perpendicular, about three feet high, and generally placed at the west end ; and the flues are formed by gathering or arching the bricks over, so as to leave a sp0ce 272 BRICK. BRICK. 273 I I between each of nearly a brick wide. The flues run straight through the clamp, and are filled with wood, coals, and breeze, pressed closely together. If the bricks are to be burnt off quickly, which may be done in 20 or 30 days, according as the weather may suit, the flues should be only at about six feet distance; but if there be no immediate hurry, they may be placed nine feet asunder, and the clamp left to bum off slowly. Floating bricks are a very ancient invention : they are so lisht as to swim in water; and Pliny tells us, that they were made at Marseilles ; at Colento, in Spain ; and at Pittane, in Asia. This invention, however, was completely lost, until M. Fabbroni published a discovery of a method to imitate the floating bricks of the ancients. According to Posidonius, these bricks are made of a kind of argillaceous earth, which was empioyed to clean silver plate. But as it could not be our tripoli, which is too heavy to float in water, M. Fabbroni tried several experiments with mineral argaric, guhr, lac-lunae, and fossil meal, which last was found to be the very substance of which he was in search. This earth is abundant in Tuscany, and is found near Casteldelpiano, in the territories of Sienna. According to the analysis of M. Fabbroni, it consists of 65 parts of silicious earth, 15 of magnesia, 14 of water, 12 of alumina, 3 of lime, and I oi iron. It exhales an argillaceous odor, and, when sprinkled with water, throws out m light whitish smoke. It is infusible in the fire; and. though it loses about an eighth part of its weight, its bulk is scarcely diminished. Bricks composed of this substance, either baked or unbaked, float in water ; and a twentieth part of clay may be added to their composition without taking away their property of swimming. These bricks resist water, unite perfectly with lime, are subject to no alteration from heat or cold, and the baked differ from the unbaked only in the sonorous quality which they have acquired from the fire. Their strength is little inferior to that of common bricks, but much greater in proportion to their weight ; for M. Fabbroni found, that a floating brick, measuring 7 inches in length, 4^ in breadth, and one inch eight lines in thick* ness, weighed only 14^ ounces ; whereas a common brick weighed 5 pounds 6| ounces. The use of these bricks may be very important in the construction of powder magazines and reverberatory furnaces, as they are such bad conductors of heat, that one end may be made red hot while the other is held in the hand. They may also be employed for buildings that require to be light; such as cookinsr-places in ships, and floating batteries, the parapets of which would be proof against red-hot bullets. The following plan of a furnace or kiln for burning tiles has been found very con- venient : — J*\g. 198., front view, a a, B b, the solid walls ot the tumace ; a a a, openings to the ash-pit, and the draught hole; b b b, openings for the supply of fuel, furnished with a sheet-iron door. Fif/^ 190. PJai! of tlu- :»sli-))ifs and uir channels c c c. Tlie principal B D D D B a a A n 198 branch of the ash-pit n r> i>, i? also the oporiinir for taking out the tiles, after removing the grate; e, the smoke flue. lu/. 2o0. Plan of the kiln seen from above. Tlie grater* h ii it. The tiles to be fired are arranged upon the spaces f f ff. 7^%. 201. is the plan and section of one of the grates upon a much larger scale than in the preceding figures. Mechanical brick moulding. — Messre. Lyne and Stainford ob- tained in August, 1825, a patent for a machine for making a considerable number of bricks at one operation. It consists, in the first place, of a cylindrical pug-mill of the kind usually em- ployed for comminuting clay for bricks and tiles, furnishca with rotatory knives, or cutters, for breaking the lumps and mixing the clay with the other materials of which bricks are commonly made. Secondly, of two movable moulds, in each of which fifteen bricks are made at once ; these moulds being made to travel to and fro in the machine for the purpose of being alter- nately brought under the pug-mill to be fitted with the clay, and then removed to situations where plungers are enabled to act upon them. Thirdly, m a contrivance by which the plungers are made to descend, for the purpose of com- pressing the material and discharging it from the mould in the form of bricks. Fourthly, in the method of constructing and working trucks which carry the receiving boards, and conduct the bricks away as they are formed. Fig. 202. exhibits the general construction of the apparatus ; both ends of which being exactly similar, little more than half of the machine is represented, a is the cylindrical pug-mill, shown partly in section, which is supplied with the clay and other 202 i'l:i Ii Hi M I |i I'rTnmrprrr Trraw i!lil!ll'll!!l!l | i||i|ni|inlljiiHlli y \ — ■tt"A'l-'}l.l*!!iil'ii'ir-l! 7 materials from a hopper above ; b b, are the rotatory knives or cutters, which are at tached to the vertical shaft, and, being placed obliquely, press the clay down towards the bottom of the cylinder, in the act of breaking and mixing it as the shaft revolves. The lower part of the cylinder is open ; and immediately under it the mould is placed in which the bricks are to be formed. These moulds run to and fro upon ledges in the side frames of the machine ; one of the moulds only can be shown by dots in the figure, the side rail intervening ; they are situated at c c, and are formed of bars of iron crossing each other, and encompassed with a frame. The mould resembles an ordinary sash window in its form, being divided into rectangular compartments (fifteen are pro- posed in each) of the dimensions of the intended bricks, but suflSciently deep to allow the material, after being considerably pressed in the mould, to leave it, when dis- charged, of the usual thickness of a common brick. The mould being open at top and bottom, the material is allowed to pass into it, when situated exactly under the cylinder ; and the lower side of the mould, when sc placed, 18 to be closed by a flat board d^ supported by the trunk e, which is raised by a lever and roller beneath, running upon a plane rail with inclined ends. Tlie central shaft, /, is kept in continual rotatory motion, by the revolution of tht upper horizontal wheel g, of which it is the axis ; and this whe'el may be turned by a hot-se yoked to a radiating arm, or by any other means. A part of the circumference of the wheel g, has teeth which are intended at certain periods of its revolution to take into a toothed pinion, fixed upon the top of a vertical shaft h h. At the lower part of this vertical shaft, there is a pulley i, over which a chain is passed that is connected to the two moulds c, and to the frame in which the trucks are supported ; by the rotation of the vertical shaft, the pulley winds a chain, and draws the moulds andf truck framee along. The clay and other material having been forced down from the cylinder into the mould, the teeth of the horizontal wheel g now come into geer with the pinion upon You L 2 N 274 BRICK. fi, and turn it and the shaft and pulley i, by which the chain is wound, and the mould at the right hand of the machine brought into the situation shown in the figure ; a scraper or edge-bar under the pug-mill having levelled the upper face of the clay in the mould, and the board d, supported by the truck e, formed the flat under side. The mould being brought into this position, it is now necessary to compress the ma- terials, which is done by the descent of the plungers k k. A friction-roller I, pendant from the under side of the horizontal wheel, as that wheel revolves, comes in contact with an inclined plane, at the top of the shaft of the plungers; and, as the friction- roller passes over this inclined plane, the plungers are made to descend into the mould, and to compress the material ; the resistance of the board beneath causing the clay to be squeezed into a compact state. When this has been effectually accomplished, the further descent of the plungers brings a pin wi, against the upper end of a quadrant catch-lever n, and, by depressing this quadrant, causes the balance-lever upon which the truck is now supported to rise at that end, and to allow the truck with the board d to descend, as shown by dots ; the plungers at the same time forcing out the bricks from the moulds, whereby they are deposited upon the board d; when, by drawing the truck forward out of the machme, the board with the bricks may be removed and replaced by another board. The truck may then be again introduced into the machine, ready to receive the next parcel of bricks. By the time that the discharge of the bricks from this mould has been effected, the other mould under the pug cylinder has become filled with the cla}'^, when the teeth of the horizontal wheel coming round, take into a pinion upon the top of a vertical shaft, exactly similar to that at A, but at the reverse end of the machine, and cause the moulds and the frame supporting the trucks to be slidden to the left end of the machine ; the upper surface of the mould being scraped level in its progress, in the way already described. This movement brings the friction-wheel o, up the inclined plane, and thereby raises the truck, with the board to the under side of the mould, ready to receive another supply of clay ; and the mould at the left hand side of the machine being now in its proper situation under the plungers, the clay becomes compressed, and the bricks discharged from the mould in the way described in the former instance ; when this truck, being drawn out, the bricks are removed to be dried and baked, and another board is placed in the same situation. There are boxes, p, upon each side of the pug cylinder containing sand, at the lower parts of which small sliders are to be opened (by con- trivances not shown in the figure) as the mould passes under them, for the purpose of Bcattering sand upon the clay in the mould to prevent its adhering to the plungers. There is also a rack and toothed sector, with a balance-weight connected to the inclined plane at the top of the plunger-rods, for the purpose of raising the plunger after the friction-roller has passed over it. And there is a sprin? acting against the back of the quadrant-catch for the purpose of throwing it into its former situation, after the pin of the plunger has risen. One of the latest, and apparently most effective machines for brick-making, is that patented by Mr. jfcdward Jones, of Birmingham, in August, 183o. His improvements are described under four heads ; the first applies to a machiHe for moulding the earth into bricks in a circular frame-plate horizontally, containing a series of moulds or rec- tangular boxes, standing radially round the circumference of the circular frame, into which boxes successively the clay is expressed from a stationary hopper as the frame revolves, and after being so formed, the bricks are successively pushed out of their boxes, each by a piston, acted upon by an inclined plane below. The second head of the spe- cification describes a rectangular horizontal frame, having a series of moulding boxes placed in a straight range, which are acted upon for pressing ihe clay by a corresponding range of pistons fixed in a horizontal frame, worked up and down by rods extending from a rotatory crank shaf^, the moulding boxes being allowed to rise for the purpose ot enabling the pistons to force out the bricks when moulded, and leave them upon the bed or board below. The third head applies particularly to the making of tiles, for the flooring of kilns in which mall or grain is to be dried. There is in this contrivance a rectangular mould, with pointed pieces standing up for the purpose of producing ai»- holes through the tiles as they are moulded, which is done by pressing the clay into the moulds upon the points, and scraping off the superfluous matter at top by hand. The fourth or last head applies to moulding chimney pots in double moulds, which lake to pieces for the purpose of withdrawing the pot when the edges of the slabs or sides are sufficiently brought into contact. " The drawing which accompanies the specification very imperfectly represents some parts of the apparatus, and the description is still more defective ; but as we are ac- quainted ^th ihe machinery, we will endeavor to give it an intelligible form, and quote those parts of the specification which point the particular features of novelty proposed to be claimed by the patentee as his invention, under the several heads." * * Mr NflwtMi, in hit London Journal, February, 18J7. BRICK. 275 Fig. 203 represents, in ele- vation, the first-mentioned ma- chine for moulding bricks. The moulds are formed in the face of a circular plate or wheel, a a, a portion of the upper sur- face of which is represented in the horizontal view, fig. 204. Any convenient number of these moulds are set radially in the wheel, which is mounted upon a central pivot, supported by the masonry b b. There is a rim of teeth round the outer edge of the wheel a a, which lake into a pinion c, on a shaft connected to the first mover; and by these means the wheel a, with the moulding boxes, is made to revolve horizontally, guided by arms with an ti- friction rollers, which run round a hori- zontal plate a a, fixed upon the masonry. A hopper, e, filled with the brick earth shown with one of the •iw,»o *u^ r— <• 41. 1. 1 • , moulding boxes in section, is fixed r^ th. Jv. I i/^^'L'" '"'^ X"^^^ ^^^^ ^^^ ^^"^^ may descend from the hopper into the several moulding boxes as the wheel passes round under it ; the earth bein- Km of the hoppe" '' "^ ^'^ '"'^'^'^ ''"^^^^ °^ ^°^^°^^ ^^ ^ ''^^^ '°"«^/> "^ ^hS rJil'^hf ,/^^ bottom of each moulding box there is a hole for the passage of a piston ^ht^K "PPer end of which rod carries a piston with a wooden pallet upon it, icting Ihlii? i .I.""" K ? ^''' f"^ '^^ ^°^^' ^"^ «^ ^^'^ ^«^ ^"^^ a s^all anli-friction roller, r«v A r i J"^^ a revolves, runs round upon the face of an oblique ring or incUned way, h A, fixed upon the masonry. ^ v*»ucu p«t of he inclined way /i, and it will be perceived that as the wheel revolves the niaton shown a? in 7. C r ^'.f "^^«;^hem, severally up the mould, into the situation K»?„ .t ' ^ -^^j ^^^' ^T '^^^"''^ '^^y """^ *° ^e removed by hand. Fresh pallets moufd.W? ^h'^K^- r°\'^' r'?^ P^^'""^' '^'y> ^"h the moulds, will be ready foJ moulding fresh bricks, when, by the rotation of the wheel a, Ihey are severally brought under the hopper, the pistons having sunk to the bottoms of their l^xL 2 iL Sn rods passed down the other side of the inclined way h ' ^ I, Ji'-t ^^T^T f^l' ft' ^^""'"^ described the first head of his invention, he would have It understood that the same may be varied without departing from the main Twect TnH '7r"T ' T^" '^'l^^ ^'''^"^^"' ^ ^^"^« «f "^«^i^^ ^»»en worked by means of an inclined track, and m such manner that bricks, tiles, or other articles made of brick earth, may be capable of being formed in a mould with pallets or boards laid wHMa he moulds, and constituting the bottom thereof, the bricks being removed from Tut^ forpTl'"' '^''^ t'r}]''' "^ ^'^'^' ''''^'' ^^^"»' ^' ^bove described. - 1 do noT, ther^ fore, confine myself to the precise arrangement of the machine here shown, though it^ the best with which I am acquainted for the purpose " inouj,n u is hiv! t^X'^^^'f ""^ ^^^ invention is another construction of apparatus .or moulding S; : ^^Zr ''.'- '" *-ff ^^"^"^^'•/'•ame. Fig. 205 is a front elevation of the ma^ t7VJ^' ^ ^^''?i'*'V^''* '^'"^ ^^J'^" transversely, a a is the standard frame-work ?,^m. w if 7^''^ \^^ ^'-M ' *? .*° ^^ mov.\AeA. Near the corners of this standard L^^Id'ill^^''"" ''rf '^ ^"^^^7i ^ ""'^ "'•"^'^^' "P«" ^^^^^ P»'-^s the frame of the mould ng boxes c, slides up and down, and also the bar d, carr ing the rods of the pis- Lnv ^\k ^f P''^°"f ''''5''' '^^ Purpose of compressing the clay in the moulding SilU't;^":aT^^^^^ ''''^' '^^^^^^ ^^^^ ^^^ *^^^-^P«"^ withthe'respectivemoulcJ The sliding frame c, constituting the sides and ends of the moulding boxes, is sup. iZltf. 7t ^? / «VP"«^' ^^^'^^ ^ /' ^hich rods pass through guides fixed to ^Zlt f ^^ '^*"^^^ ^i:*"?.^ "" ""' *"^ "' ^^^ ^^^e'- end of each there il a roller, bearing upon the levers g, on each side of the machine, but seen only in fig. 181, which levers 276 BRICKS. BRICKS. when depressed, allow the moulding boxes to descend, and rest upon the bed or table of the machine h h. 206 '[ ^1 ^' gc> o| T T In this position of the machine resting upon the bed or table, the brick-earth is to be placed upon, and spread over, the top of the frame c, by the hands of workmen, when the descent of the plunger or pistons c c c, will cause the earth to be forced into the moulds, and the bricks to be formed therein. To effect this, rotatory power is to be applied to the toothed wheel i, fixed on the end of the main driving crank shaft k k, which on revolving will, by means of the crank rods 1 1, bring down the bar a, with the pistons or plungers eee, and compress the earth compactly into the moulds, and thereby form the bricks. When this has been done, the bricks are to be released from the moulds by the moulding frame c rising up from the bed, as shown in Jig. 205., the pistons still remain- ing depressed, and bearing upon the upper surfaces of the bricks. The moulding frame is raised by means of cams in, upon the crank shaft, which at this part of the operation are brought under the levers^, for the purpose of raising the cams and the slidmg rods /, into the position shown in^^r. 206. The bricks having been thus formed and released from their moulds, they are to be removed from the bed of the machine by pushing forward, on the front side, fresh boards or pallets, which of course will drive the bricks out upon the other side, whence they are to be removed by hand. There is to be a small hole in the centre of each pallet, and also in the bed, for the purpose of allowing any superfluous earth to be pressed through the moulding boxes when the pistons descend. And in order to cut off the projecting piece of clay which would be thus formed on the bottom of the brick, a knife-edge is in some way connected to the bed of the machine ; and as the brick slides over it, the knife separates the pro- tuberant lump ; but the particular construction of this part of the apparatus is consi- dered to be of little importance ; and the manner of effecting the object is not clearly stated in the specification. The patentee proposes a variation in this construction, which he describes in these words : " It will be evident that in place of having the moulds to rise, they may, by suitable arrangements, be made to descend below the bricks. In this case, in place ot the boards, stationary blocks to receive the pallets must be fixed on the bed of the machine, and these blocks must be shaped in such a manner as to allow of the moul'^«» passing over them : and then it will be desirable to use the first part of my improve- ments, that of having the pallets within the moulds at the time of moulding the bricks ; or in case of working with exceedingly stiff brick-earth, the pallets may be dispensed with." In 1849, 1,503,961,106 bricks paid duty in the United Kingdom ; the revenue from which was 461,582Z. 68. Id. BRICKS. Mr. F. "W. Simms, C. R, communicated to the Institution of Civil En- g'neers, in April and May, 1843, an account of the process of brick-making for the over railway. The plan adopted is called slop-moulding, because the mould is dipped into water before receiving the clay, instead of being sanded as in making sand-stock bricks. The workman throws the proper lump of clay with some force into the mould, presses it down with his hands to nil the cavities, and then strikes off the surplus clay with a stick. An attendant boy, who has previously placed another mould in a water trough by the side of the moulding table, takes the mould just filled, and carries it to the floor, where he carefully drops the brick from the mould on its flat side, and leaves it to dry ; by the time he has returned to the moulding table, and deposited the empty 277 mould m the water trough, the brickmaker will have filled the other mould, for the Doy to convey to the floor, where they are allowed to dry, and are then stacked in rea dmess for being burned in clamps or kilns. The average product is shown in the fol lowing table: — Force employed. 1 moulder 1 temperer 1 wheeler 1 carrier boy 1 picker boy Area of land. Roods. Perches. 14i Duration of season Produce per week. Prodace per season. Weeks. 22 Bricks. 16,100 Bricks. 364,200 .«ip w \n ♦'^^^ ^i^^ P'"*'**''''^ m sand-stock bncks is to that of slop-bricks in th« «nH tWn t f I li ' the amount of labor is as 7 to 4; while the quantity of land, t^?v nf .li . A P^' thouf nd, IS nearly the same in both processes. The qua^ ThVLc? if t?'"" K^^'"' ^^^ ^o? "^^^ ^V**^ ^^^^ «^ 10 <=^- Slhs. per thousand bricks. ft,«v TL1h\' K^^^^«,7^^2/. U ed. per thousand. The slop-made bricks are «f h:« K^lfi M ^^''n ^^? ^^t sand-stock. Mr. Bennett stated to the meeting, that ?9 rSS h ?M t r ^""^^^^ ^^^ ^""^'^^^ ^"°'^^'' «^ sand-stock bricks moulded was 32,000; but that frequently so many as 37,000, or even 50,000, were formed. The total amount m the shrinkage of his bricks was i » of an inch upon 10 inches in length ; but this diflered with the diiferent clays. Mr. Simms objected to the use of machinery in bnck-making, because it caused economy only m the moulding, which constituted no more than about one eighth of the total expense. The principal varieties of bricks are called malm,paviors, stocks, grizzles, places, nnd •huffs. For the first and best kind, the clay was washed and selected with care: stocks were good enough for ordinary building purposes ; the rest are inferior. The diilerence m price between malms, paviors, and stocks, was Ws. or 20*. per 1,000: be- tween stocks and places, 10*. The average weight of a sand-stock brick L fully 5 pounds, that of a slop is 1 pound more. I believe that the siliceous sand on the surface of the sand-stocks is useful in favoi^ mg adhesion of mortar, by the production of a silicate of lime. To smooth alnminona bricks, mortar sometimes forms no stony adhesion. Mr. Prosj.er, of Birmingham, makes bricks by pressure. The clay is first ground upon a shp Ailn, as if for making pottery, then ground to a fine powder, and in that dry state it is subjected to the heavy pressure of about 250 tons, in strong metal moulds, by which means it is reduced to about one third of its original thickness. J he clay seems to have retained sufficient moisture to give it cohesion, and the tiles are perfectly sharp at the edges. They being then baked within seggars by the heat of * • ?'if . "" ^^**^^ ^"^ ^^^ ^^^^^S' The bricks thus formed are denser than usual, and weigh 6| lbs., with a specific gravity of 2*5. Fig, 207., represents Mr. Hunt's brick-making machine. The principal working parts consist of 2 cyhnders, each covered by an endless web, and so placed as to fonn the front and back of a hopper, the two sides being iron plates, placed so that whea the hopper is filled with tempered clay from the pug-mill, the lower part of the hopper, and consequently the mass of clay within it, has exactly the dimensions of a brick. Beneath the hopper an endless chain traverses simultaneously with the movement of the cyhnders. The pallet-boards are laid at given intervals upon the chain, and bemg thus placed under the hopper, while the clay is brought down with • slight pressure, a frame with a wire stretched across it is projected throug the H 278 BRICKS. i:i .;. t PI I mass of clay, cutting off exactly the thickness of the brick, which is removed at the same moment by the forward movement of the endless chain. This operation is repeated each time that a pallet-board comes under the hopper. The chief object of this machine, which is worked by hand, is to produce good square compact bricks of uniform quality, using only a slight pressure. It has been found to be very difficult to dry bricks made by machinery, where a considerable pres- sure has been employed, because, before the evaporation from the centre of the clay is completed, the surfaces have become hard and peel off. The present machine is in operation in several parts of England, producing usually about 1200 bricks per hour, while each machine requires only 2 men and 3 boys to tend it, and to take off the bricks. The clot-moulders are dispensed with, and the workmen are common labourers, so that professed brick-makers at higher wages are not needed. Fig. 208. shows Mr. Hunt's machine for making tiles, and it is on the same principle^ It consists of two iron cylinders, round which webs or bands of cloth revolve, whereby the clay is pressed into a slab of uniform thickness, without adhering to the cjlinde^Y. It is then carried over a covered wheel, curved on the rim, which gives the tile the •emi-cylindrical or other required form \ after which the tiles are poUshed and finished by passing through three iron moulds of a horse-shoe fonn, as shown in the centre of the cut, while they are at the same time moistened from a water cylinder placed abore tbem. The tiles are next cut off to such lengths as are wanted, and carried away by an endless web, whence they are transferred by boys to the drying shelves. Flat tiles, for sole pieces to draining tiles, are formed in nearly the same manner, being divided into two portions while passing through the moulds ; the quantity of clay used for one draining tile being as much as for two soles. The method of making bricks in the vicinity of London differed from that of almost all other places, because the material there employed is not pure clay, but a loam of a slightly cohesive nature, which will not admit of its being used in the natural gtate and burned in close kilns with coal ; but with an admixture of ashes it becomes sufficiently tenacious to be formed into bricks, by inducing a slight semi-fusion. But the coal-ashes are also of advantage in the process of burning, because they enable the fire to spread gradually from the lower tiers, through the whole mass in the kiln or clamp, and thus obviate the effect of an intense partial heat, where distinct coal fires are trusted to alone, whereby the bricks nearest it get vitrified and glazed. The brick kilns and clamps round London, and other large cities, which are fired with the breeze-rubbish collected from dust holes, that contain the refuse of kitchens, &c., emit, in consequence, most unpleasant effluvia ; but brick-kDns fired with clean coke or coals, give out no gases of a more noxious nature than common household fires. The consideration of this subject was closely pressed upon my attention on being con- sulted concerning an injunction issued by the chancellor against a brick clamp in the Isle of Wight, fired with clean coke cinders from the steam-engine furnace at Ports- mouth Dock Yard. The bricks being of the description called sand-stock, were of course made in moulds very slightly dusted with sand, to make them fall freely out. The sand was brought from Portsmouth harbor, and on being subjected to a degree of heat, more intense certainly than it would suffer in the clamp, was discovered by two chemical witnesses to give out traces of hydrochloric acid. Not content with this trivial indication, the said chemists, in their evidence before the courts of law, paraded a train of goblin gases, as the probable products of the pre-adjudicated clamp. As it is well known to the chemist that common salt strongly ignited in contact with moist sand will emit hydrochloric acid, there was nothing remarkable in the above BRITANNIA TUBULAR BRIDGK 2V9 observation, but I ascertained that the sand with which the moulds were strewed would give out no hydrochloric acid, at a heat equal at least to what the bricks were exposed to in a clamp 10 or 12 feet high, and fired at its bottom only with a layer of cindera 3 or 4 inches thick. But I further demonstrated that the entire substance of the brick with its scanty film of sand, on being exposed to ignition in a suitable apparatus, gave out— not hydrochloric or any other corrosive acid, but ammonia gas. Hence, the allegations that the clamp set forth a host of acid gases to blight the neighbouring trees, were shown to be utterly groundless ; on the contrary, the ammonia evolved from the heated clay would act beneficially upon vegetation, while it was too small in quantity to annoy any human being. A few yards to leeward of a similar clamp, in full activity, I could perceive no offensive odour. All ferruginous clay, when exposed to the atmo- sphere, absorbs ammonia from it, ^nd of course emits it again on being gently ignited. It is a reproach to science when, as in the above case, it lends itself to judicial prejudice and oppression. Messrs. Whalley and Lighloller have patented apparatus for manufacturing bricks and tiles, which combines the pug mill, pressing cylinder, screens and die-plate all in one machine ; thereby effecting great economy m time and labour, and also in the cost of the machinery itself The combination alone is claimed. BRIMSTONK {Soufre, Fr. ; Sckwefel, Germ.) Sulphur, which see. BRITANNIA TUBULAR BRIDGE (opening of the). The opening of this mag- nificent structure, looked forward to with so much interest, came oft' on the 5th of March, 1849, at dawn with the grandest success. At precisely seven o'clock, the adventurous convoy, progressing at a speed of seven miles an hour, was lost sight of in the recess of the vast iron corridor. Instead of being driven through with a dispatch indicative of a desire on the part of those who manned it to get in and out with the utmost expedition, the locomotives were propelled at a slow and stately pace, with a view of boldly proving by means of a dead weight the calibre of the bridge at every hazard. The total weight of the locomotives was 90 tons. The appearance of the interior of the tube during the experiment was of a novel and remarkable character. The locomotives were brought to a standstill in the centre of each of the great spans, without causing the slightest strain or deflection. The first process, that of goin^ through the tube and returning, occupied altogether 10 minutes. The second experimental convoy that went through consisted of 24 heavily laden waggons filled with huge blocks of Brymbo coal, in all, engines included, an aggregate weight of 300 tons. This was drawn deliberately througli, at the rate of from eight to ten miles an hour, the steam working at quarter power. During the passage of this experimental train through the tube, a breathless silence prevailed until the train rushed out exultingly, and with coloui-s flying, on the other side of the tube, when loud acclamations arose, followed at intervals by the rattle of artillery down the Straits. Upon the return, which occupied about seven minutes, similar demonstrations ensued, and during the progress of the train those who stood upon its top to ascertain any possible vibration, reported they could detect no sensible deflection. An ordeal stronger still was then resorted to ; a train of 200 tons of coals was allowed to rest with all its weight for two hours in the centre of the Carmarthenshire tube, and at the end of the time, on the load being removed, it was found to have caused a deflection of only four-tenths of an inch. It is remarkable that this amount of deflection is not so much as one half hour of sunshine would produce upon the structure, it being moreover calculated with confidence that the whole bridge might with safety, and without injury to itself^ be deflected to the extent of 13 inches. These loads, it is most material to remember, are immensely more than the bridge will ever be called on to bear in the ordinary run of traffic, though the engineers are of opinion that it would support with ease, and without much show of deflection, a dead weight on its centre of 1,000 tons. Twelve miles an hour is the limit of speed at which Mr. Stephenson intends that trains shall at first go through, more particularly as there are sharp curves at the termini of the tube. The effect of the recent hurricane on the calibre of the tube has proved that its lateral surface strength is sufficient, and far more than sufficient, to resist the strongest wind. It is calculated that, taking the force of the wind at 50 lbs. on the square foot, an excessive supposition, the resistance offered by the bridge would be 300 tons X 2 = 600 tons, which is not two thirds of its own weight. The wind going at 80 iniles an hour the rush of a hurricane would only press in the ratio of 128 tons on the side. It is intended, when both tubes are up, to brace them together with stays, so as to counteract any possible oscillation. ^ , , . , i ^ i.m The great work has now been four years m hand, and is nearly complete, while Telford*s suspension bridge took eight years. The floating and actual transference of the tubes have occupied since June last, a short period, when the bulk of the fabric is taken into consideration. Great fears wera 380 it i;!! I BRONZE. entertained for its safety during the late gales, from the recollection in this part of the country of the damage done to Telford's suspension bridge. BRITISII GUM. The trivial name given to starch, altered by a slight calcination m an oven, whereby it assumes the appearance and acquires the properties of gum, being soluble in cold water, and forming in that state a paste well adapted to thicken the colours of the calico printer. See Dextrine and Starch. BROMINE, one of the archseal elements, which being developed from its combination! at the positive pole of the voltaic circuity has been therefore deemed to be idio-electro- positive like oxygen and chlorine. It derives its name from its nauseous smell, BooS/ioj, mtor. It occurs m various saline springs on the continent of Europe, in those of Ashby de la Zouche, and some others in England ; in the lake Asphaltites, in sponges, in some marine plants, in an ore of zinc, and in the cadmium of Silesia. At ordinary tempera tures It IS liquid, of a dark brown colour in mass, but of a hyacinth-red in thin layers. Its smell IS rank and disagreeable, somewhat like that of chlorine. It has a very caustic taste. Its specific gravity is 2-966. Applied to the skin it colours it deep yellow and corrodes it. One drop put within the bill of a bird suffices to kiU it It combines with oxygen with feeble affinity, forming bromic acid. Its attraction for hydrogen being far more energetic, it forms therewith a strong acid, the hydrobromic. Bromine dissolves very sparingly in water, but it is very soluble in alcohol and ether. It combines with carbon, phosphorus, sulphur, and chlorine, as well as with most of the metals. Jrom its scarcity it has not hitherto been applied to any purpose in the arts, except photography; but it is supposed to possess powerful discutient effects upon scrotulous and other glandular tumours, whence the waters containing it are pre- scnbed as an internal and external remedy in such forms of disease. ,..^^^.^2^ -.^ compound metal consisting of copper and tin, to which sometimes a little zmc and lead are added. This alloy is much harder than copper, and was employed by the ancients to make swords, hatchets, «fec., before the method of working iron was generally understood. The art of casting bronze statues may be traced to the most remote antiquity, but it was fii-st brought to a certain degree of refinement by Iheodoros and Roecus of Samoa, about 700 yeai-s before the Christian era, to whom the invention of modelling is ascribed by Y\\\\^\ The ancients were well aware that by alloying copper with tin, a more fusible metal was obtained, that the process of casting was theretore rendered easier, and that the statue was harder and more durable ; and yet they frequently made them of copper nearly pure, because they possessed no means of determining the proportions of their alloys, and because by their mode of managing the fire, the copper became refined in the course of melting, as has happened to many founders in our own days. It was during the reign of Alexander that bronze statuary received its greatest extension, when the celebrated artist Lysippus succeeded by new processes of moulding and melting to multiply groups of statues to such a degree that Fhny called him the 7noh of Alexander. Soon afterwards enormous bronze colossuses were made, to the height of towers, of which the isle of Rhodes possessed no less than one hundred- The Roman consul Mutianus found 3,000 bronze statues at Athens, 3,000 at Rhodes, as many at Olympia and at Delphi, although a great number had been previouslv carried off from the last town. ^ In forming such statues, the alloy should be capable of flowing readily into all the parts of the mould, however minute ; it should be hard, in order to resist accidental blows, be proof against the influence of the weather, and be of such a nature as to acqmre that greenish oxidized coat upon the surface which is so much admired in the antique bronzes called ^patina antiqucu The chemical composition of the bronze alloy 18 a matter therefore of the fii-st moment The brothers Keller, celebrated founders in the time of Louis XIV., whose chefs-d'oeuvre are well known, directed their attention towards this point, to which too little importance is attached at the present day. The statue of Desaix in the place Dauphine, and the column in the Place Vendome, are noted specimens of most defective workmanship from mismanagement of the alloys of ^,.*^-" ^^^y *^^ composed. On analysing separately specimens taken from the bas- rehefs of the pedestal of this column, from the shafts and from the capital, it was found that the first contained only 6 per cent of alloy, and 94 of copper, the second much less, and the third only 0-21. It was therefore obvious that the founder, unskilful in the melting of bronze, had gone on progressively refining his alloy, by the oxidizement of the tin, till he had exhausted the copper, and that he had then worked up the refuse BConaB in the upper part of the column. The cannons which the government furnished him for casting the monument consisted of — Copper - - - 89-360 Tin - - - lC-040 Lead - _ . 0102 Silver, zinc, iron, and loss 0-498 100-000 ■bi^^:. BRONZE. 281 to'^nr"tl?i°f!Hf ^^^ ''""""^^ bas-reliefs was so ill-executed, that the chiselers employed besfZ sooonn f removed no less than 70 tons of bronze, which was given tC Copper Tin Zinc Lead No. 1. No. 2. No. 3. The mean. 91-30 91-68 91-22 91-40 1-00 2-32 1-78 1-70 6-09 4-93 6-67 6-63 1-61 1-07 1-43 1-37 10000 100 00 100-00 100-00 The analysis of the bronze of the statue of Louis XV. was as follows :- ZhiT"" ?0-30 ^^' 'P^'^^'^ ^*^*^y ^as 8-482. Tin 4-10 Lead 3*15 100-00 fa tt,e hundred.o^ .i„c be aSdet '™ey^?„'Lt1 LC'a Ltlo^'zeZr 'xf T Of the Kellers is famous for this effect Th^ m«^oi\,u ij i. ^^onze tint. The alloy successive stamps of the nress and ^ J^! lH '^''"^^ ^f subjected to three or four plunged into cold water. ^ ' ^ ^ '"^'""^ ^^^^^^^ '^'^ ^ow by being heated and alby L'sTfi^Llmtergr:!nT^^^^^ 'fSTfJ'' ''' P^^-^ copper 78, tin 22. Thi. added are rather prejud cLT and Z^C^fn^r" c .^^^^ The other metals sometimes English bells conLt^fsoilfer^^^^^ of the founders. Some of the jn^^sucb large quantity is apf I ^^ tl^^^^^^^i .^ ':^^fZ fo^eiiXTr^^er/^^^^ v^ thl^'^^a^J^T "^-"^ f^ ^-^ ^-"^ ^^^^ ^s gongs, from the word /^Aou^l whichT^^^tebeTr^^^^^^^^ °^'^.^'^' '\'^ «^^ """^ tain nothing hut copper and tin • in the nronortS.r 78^ ? v ^r^ '^'''^" ^'^^^ ^^^^ «««- the latter. Their specificTavitvTs 8 8 1 5 ^T v if ^^ 5 ^^^ ^''™^'' "^^«^ ^^^ 22 of glass, but by being pCed at a c^«r"^Pd hit • "^^''^Z^'"' ""^'^^ '^'' ^' ^' ^"^'^^ ** iwo discs of iron^o keen it insSn/^r^^^^^ water and confined between consist of 80 parts coppe? and 20 tin '' '' ^''°°''' '""^^ ^"^ malleable. The cymbal. ror^Xh t^wo^wl^atSt Krc"^^^ ''V'' ^^ --"-- P-ess, lips tempered in the same wa? Ancient warlike wPonn'rT ^"'* ^^""'^^"^ ^'""^^ '^^ pounded; swords were formS of S^Hopper and ToF^ balistffi consisted of 97 copper, and 3 tinf ' ^ "" ^^ P^'*'' ^^« ^P"^?^ ^^ Cannon metal consists of about 90 or 91 copper, and 10 or Q nf lir, t? *i. mcnts of Papacino-d'Antony, made at Turin in 1770 if VnnL k* . ^u"""" ^^^ ^"^P^"' alloy for great guns is from 12 to 14 parts of tn to 100 y^^^^'' ^^^^ ^^% »«»st proper tiUiere concluded from his experimXll'at Lua^^^^^^ "^T^i peZ^t^:r:^;;/J:Z'^^^^^^ ^-"y o^^--, and take pasty consistencrdoes not n'X - ^h« I ' ''''P^'' """^ "''"^^ ^' ^'^^^ ^"^^^ «<* » liable to cmck in'coolfn " Ld is too t n^.h ''T' '' Tr '"^ ^^^"'^ ^°° '""ch amalgam, is the q..antity of zinc iicr^nsed to Zi-p f. *?°, 'f ' ?" '^' ''^'''^' *^^ '^^ t"^"^^- ' W^re suitable to[he eiWer Tfou^^^^^^ ^^'^''^ '} ^^'^"''^ '«^^ '^'^ J^llow color for making sucnrname^tKoi'ze anS ^'"' ^^'^?'^^'* '^ P-'-«»>»<^ the best, as they unite clo«;eness of^\nZi,h^^ .1 ^"""^^^ "^ proportions are probably 18, tin 3 or L lead ^ orS Tn thSv^ v u^ '''^'' ^°^^ ^^^Mes. Copper 82, zini minishcd and\he density [s'i/ conta.ns met lead, the tenaci.y is di- AnothcT alloy, which i^Ia^d to rrSl 7 -. '^P^i^^^^^We for pieces of small dimensions tily of gold h^s the followin/.?^^^^^ ^r ' ^'''''"^ only two thirds of the ordinary quan- lead, 0.^24.' ^^ composition: copper, 82-257; zinc, 17-481 ; tin, 0^238, ti^ef:iCl^'j^^^^^^^^^ and otherobjects madefrom these alloys by (binoxalate of nofaih \ areTn hi ^- ^ of sal-ammoniac, and half a drachm of salt of jJ,rrel less Tinegi A hat nencl be^nlT ^^^ '" - '" """'" '^'^'''''' (^"^'''^> "^^^'^' Vol. I ^ ^ ^'^^^^ ""*" ^^^ ^°^"t'«n> ^^^ Pressed gently betweea ^ LI ^M : i u^ h: 282 BRONZE. the fingers, is to be rubbed equaDy over the clean surface of the object, slightly wanned in the sun or at a stove ; and the operation is to be repeated tiU the wished-for shade is obtained. (See Gilding.) * .. i c*-^ The bronze founder ought to melt his metals rapidly, m order to prevent the loss ol tin, zinc, and lead, by their oxydizement. Reverberatory furnaces have been long used for this operation ; the best being of an elliptical form. The furnaces vn\i\ dome tops are employed by the bell-founders, because their alloy being more fusible, they do not require 60 intense a heat ; but they also would find their advantage in using the most rapid mode of fusion. The surface of the melting metals should be covered with small charcoal, oi coke ; and when the zinc is added, it should be dexterously thrust to the bottom of the melted copper. Immediately after stirring the melted mass so as to incorporate its ingre- dients, it should be poured out into the moulds. In general, the metals most easily al- tered by the fire, as the tin, should be put in last. The cooling should be as quick as possible in the moulds, to prevent the risk of the metals separating from each other in the order of their density, as they are very apt to do. The addition of a little iron, m the form of tin-plate, to bronze, is reckoned to be advantageous. One part of tin, and two parts of copper (nearly one atom of tin and four of copper, or more exactly, 100 parts of tin, and 215 copper), form the ordinary speculum metal of re- flecting' telescopes, which is of all the alloys the whitest, the most brilliant, the hardest, and the most brittle. The alloy of 1 part of tin, and 10 of copper (or nearly one atom of the former to eighteen of the latter), is the strongest of the whole series. Ornamental objects of bronze, after being cast, are commonly laid upon red-hot coals till they take a dull red heat, and are then exposed for some time to the air. The sur- face is thereby freed from any greasy matter, some portion of the zinc is dissipated, the alloy assumes more of a coppery hue, which prepares for the subsequent gilding. The black tinge which it sometimes gets from the fire may be removed by washing it with a weak acid. It may be made very clean by acting upon it with nitric acid, of specific gravity 1-324, to which a little common salt and soot have been added, the latter being of doubtful utility ; after which it must be well washed in water, and dried wif h rags or saw-dust. , r 1 Bronzing is the art of giving to objects of wood, plaster, fee, such a surface as makes them appear as if made of bronze. The term is sometimes extended to signify the pro- duction of a metallic appearance of any kind upon such objects. They ought first to be smeared over smoothly with a coat of size or oil varnish, and when nearly dry, the me- tallic powder made from Dutch foil, gold leaf, mosaic gold, or precipitated copper, is to be applied with a dusting bag, and then rubbed over the surface with a linen pad ; or the metallic powders may be mixed with the drying oil beforehand, and then applied with a brush. Sometimes fine copper, or brass filings, or mosaic gold, are mixed previously with some pulverized bone-ash, and then appUed in either way. A mixture of these powders with mucilage of gum arable is used to give paper or wood a bronze appearance. The surface must be afterward burnished. Copper powder precipitated by clean plates of iron, from a solution of nitrate of copper, after being well washed and dned, has been em- ployed in this way, either alone or mixed with pulverized bone-ash. A finish is given tft vorks of this nature by a coat of spirit varnish. A white metallic appearance is given to plaster figures by rubbmg over thein an amaU gam of equal parts of mercury, bismuth, and tin, and applying a coat of varnish over it. The iron-colored bronzing is given by black lead or plumbago, finely pulverized and washed. Busts and other objects made of cast iron acquire a bronze aspect by being well cleaned and plunged in solution of sulphate of copper, whereby a thm film of this metal is left upon the iron. « . i » • r Copper acquires by a certain treatment a reddish or yellowish hue, m consequence ot a little oxide being formed upon its surface. Coins and medals may be handsomely bronzed as follows: 2 parts of verdigris and 1 part of sal ammoniac are to be dis- solved in vinegar ; the solution is to be boiled, skimmed, and diluted with water till it has only a weak metallic taste, and upon further dilution lets fall no white precipitate. This solution is made to boil briskly, and is poured upon the objects to be bronzed, which are previously made quite clean, particularly free from grease, and set in another copper pan. ftiis pan is to be put upon the fire, that the boiling may be renewed. The pieces under operation must be so laid that the solution has free access to every point of their surface. The copper hereby acquires an agreeable reddish brown hue, without losing its lustra But if the process be too long continued, the coat of oxide becomes thick, and makes the objects appear scaly and dull. Hence they must be inspected every five minutes, and be taken out of the solution the moment their colour arrives at the desired shade. If the solution be too strong, the bronzing comes off with friction, or the copper gets covered with a white powder, which becomes green by exposure to air, and the labour is con- sequently lost. The bronzed pieces are to be washed with many repeated waters, and carefully dried, otherwise they would infallibly turn green. To give fresh-made bronze BRONZE. 283 -n^/ l^!V *r u^"*^ appearance, three quarters of an ounce of sal ammoniac, and a drachm and a half of binoxalate of potash (salt of sorrel) are to be dissolved in a quart of vinegar. 1 . ^ ?n •?" ^^'•^'^'■"sh moistened with this solution is to be rubbed over the clean bri-ht metal, till its surface becomes entirely dry by the friction. This process must be repeat- ed several times to produce the fuU effect ; and the object should be kept a litle warm nvpJ'nr^'T'l!'^ """^ f^u''"^ ^^''^'^ *=°^«'' ^y """^^i"? »^ ^»t^ * s^l«tio" oC the common liver of sulphur, or sulphuret of potash. »rIK ^*'*"^^^ ;^^. ^^'t *o ^'•onze their copper vessels bv taking 2 ounces of verdi- gris, 2 ounces of cinnabar, 5 ounces of sal ammoniac, and 5 ounces of alum, all in powder making them into a paste with vinegar, and spreading this i.retty thick !ke a S;£lL'oU7a firVluMrb^cTer^^r'"^^ ^^^ P-- '^ ^^^- '« b^helfa litti: TfiPr wZh .-7 • ' . ^- "If ""'formly heated. It is next cooled, washed, and dned ; after which it is treated in the same way once and again till the wished for color is obtained. An addition of sulphate of copper makes the color inclinrmore to che^nut brown, and of borax more to yellow. It is obvious that the cinnabarroTc^s a thin c^t n J^f'bi '^^ ^PP^^^-^lfe of antique bronze to modem articles, we should dissolve 1 part of sal ammoniac, 3 parts of cream of tartar, and 6 parts of common TaU in 12 parts of hot water, and mix with the solution 8 parts of a solSn of n" tra e of copper of specific gravity M60. This compound, when applied repeatSlly 1^ a moderately damp place to bronze, gives it in a short time ^durable gr^n coaL which becomes by degrees very beautiful. More salt gives it a jeUov^ish tll^e Lss mirdant ' ' ^ ^^'^' ^'^^''^'' "^ '^^ ^^^^^^-^'^^^ accelerates the operation of ^e Broxze Powders, an article much used of late in the decorative painting of houses. Ac ^ey are prepared of every various shade, from that of bright gold to oraZ^dark copper, emerald green. Ac Pale gold is produced from an alloy of 13i of copper and 21 of zmc: cnmson metallic lustre-from copper: do. paler, copper Ld a?e?v iiUle one: green bronze with a proportion of verdigris: another fine orange by ll/ Upe^ o??hAw"'' tT'- '■" ^ ^* '^PP'': ^^^ 2i zinc: a beautiful pale gold from an aZ^ of the two metals in atomic proportions. See Atomic Weights ^ U^t!iA-^.'^-^'^T^t^ '"*'' r'^ ?"^ ^^*^^« "^'^^ <^»^ef"l annealing, and these are levigated into impalpable powde^^along with a film of fine oil to prevent oxidiztmenL LtrTwV^y^^riremer.'^^ ""^^^^^^^^ -«""^-^- ^^ ^- ---^-^ ^r^oll^lr'"'' 0/ gun^arrel, and other arms.-By this process, the surface of several !^i frL r.!T ''T'f^^'^ '^'"'"'- ^'"°'^" ^°^°"- "^^'^ preparation, which prt.tects the ^ from rust, and a so improves its appearance, is chiefly employed for the barrels of tJI 2'"^;^?%*"ru °*'^'^.''' "'^^^ to conceal the fire-arms from the eame and the enemy, ^e browi round """" '' Damascus, in which dark and bright lines run through ^ This operation consists in producing a very thin uniform film of oxyde or rust upon the Urvamlr'"^ * ^^^ ''" '"'^^'^ ^^ '*"^^''*= '^*'' °''^'" '*' *"■ ^'^^^^"S '^ ^'^^^ »^^1- Several means may be employed to produce this rust speedily and well. The effect fJ^J ^^JS^^l""^ by enclosing the barrels in a space filled with the vapor of muriatic •cid. Moistening their surface with dilute muriatic or nitric acid, will answer the same purpose. But the most common material used for browning, is tho butter or chloride wTJTr// if •' on account of Us being subservient to this purpose, has been called J^tng salt It IS mixed uniformly with olive oil, and rubbed upon the iron sli-htly heated ; which is afterwards exposed to the air, till the wished-for degree of brownii- ^ The hrntn t ^T Tk^T' '' '"^f.^ ^? ^""^ '^' ^"^'°^°»y' '^ *l"'<^ken its ope^ah^on polished, either by the steel burnisher, or rubbed with white wax, or varnished with a •olution of 2 ounces of shellac, and three drachms of dragons blood, inl^n^^oTspii^ The following process may also be recommended : Make a solution with half as Tonnotl ^r^l^'h'f } *"" ''''''''^f ^"^^^^ 'P^"* «^ ""'^^^ 1 «"»«« of spirit of wine, Im fin .ll'".f ' '?PP''' ^""^ L?^"^^ «^ "°«t"^« o^ ^^^ i« «o mSch water a^ filed ^hMTk 5 if "^ w ""/^f "'^- J^"" ^^ ^^^^•l *^ ^« browned must first of all be med and polished bright, and then rubbed with unslaked lime and water to clear away with t W^ T?-*^' touch-hole must be filled with wax. The barrel is then to be ^ubbed moi«tin!^ '?•'"'' nPP^"^.^ ^'''^'' ^^^ «^ * «P«»g«' *»U the whole surface be equally ThTannll;..^ '" f .7'? *^.j*«° the inch; olive oil is then allowed to flow free^ from a stopcock over the centre of the sieve on to the leaf metal which is briskly moved over the surface of the sieve with a wire brush, untd the whole is forced through into a vessel below. This mixture of metal and oil is then introduced through a funnel hopper of the triturating machine, and spreading among the rods is caused by their rotation to approach the periphery of the steel bed beneath, and escape into a circular trough, whence they are conducted by a spout into another vessel In this progress the metal is acted upon by polished hemispherical bottoni ends of upright rods, as they S^end and descend the corrugated surface of the steel bed. and which by a tearing and burnishing operation, separate t^e coarse pieces of leaf into a multitude of polished Seles By being passed three times through the machine, the metal is reduced to the quality of a coafse bronze powder ; and is then subjected to a similar machine con- tahi?ng sm^aller rods, tossed up and down by the revolution of the corrugated angular bed of which they rapidly dance till the requisite fineness be produced. The content, of the vlsel wMch aVe usually 10 pounds of metal and 10 pounds of oil, are then put Lato a strong W made of thfee thicknesses of fustian, with their respective seams at Afferent pafts of the circumference, so as to prevent the metallic particles from passmg through. This bag is subjected to the action of a hydraulic press, of about 300 tons upon a bag of one foot diameter, neariy all the oil is expelled. The empty bag is filled with boiling water, and again squeezed; and after two or three repetitions of this washing all the oil comes out in the form of an emulsion. The bag now contains only a denS lump of bright metallic particles of nearly the gravity of the original metal. This lump is cut with a knife into slices about half an inch thick, and exposed to the air of a warm room, where the moisture evaporates, and the slices may then be crumbled into powder. (Newton's Journal, xxiv. 321.) * BRONZING {of Objects in Imitation of Metallic Bronze). Plaster of Paris, paper wood, and pasteboard, may be made to resemble pretty closely the appearance of articled of real bronze, modern or antioue. The simplest way of giving a brilliant aspect of this kind 18 with a varnish made of the waste gold leaf of the beater, ground L on a porphyry slab with honey or gum-water. A coat of drying linseed-oil should be first applied, and then the metallic powder is put on with a linCn dossil. Mosaic gold ground up with six parts of bone-ashes has been used in the same way. When it is to be put on paper, it should be ground up alone with white of eggs or spirit varnish, applied with a brush, and burnished when dry. When a plate of iron is plunged into a hot solution of sulphate of copper, it throws down fine scales of copper, which beinir repeatedly washed with water, and ground along with six times its weight of bonS ashes, forms a tolerable bronzing. ^ Powdered and sifted tin may be mixed with a clear solution of isinglass, applied with a brush, and burnished or not, according as a bright or dead surface is desired. Gypsum casts are commonly bronzed by rubbing brilliant black-lead, graphite, upon them with a cloth or brush. Real bronze long exposed to the air gets covered with a thin lilm of carbonate of copper, called by virtuosi antique cerugo {patine antique, Fr.). liiis may be imitated in a certain degree by several applications skilfully made. The new bronze bein^ turned or filed into a bright surface, and rubbed over with dilute aquafortis by a linen rag or brush, will become at first greyish, and afterwards take a greenish blue tint; or we may pass repeatedly over the surface a liquor composed of 1 part of sal ammoniac, 3 parts of carbonate of potash, and 6 of sea-salt dissolved in 12 parts of boiling water, to which 8 parts of nitrate of copper are to be added • the trnt thereby produced is at first unequal and crude, but it becomes more uniform and softer by time. A fine green-blue bronze may be obtained with very strong water of ammonia alone, rubbing it at intervals several times upon the metal. The base of most of the secret compositions for giving the antique appearance is Yinegar with sal ammoniac. Skilful workmen use a solution of 2 ounces of that salt in an li^nglish quart of French vinegar. Another compound which gives good results is made with an ounce of sal ammoniac, and a q^uarter of an ounce of salt of sorrel (binox- alate of potash) dissolved in vinegar. One eminent Parisian sculptor makes use of a mix- ture of half an ounce of sal ammoniac, half an ounce of common salt, an ounce of spirita of hartshorn, and an English quart of vinegar. A good result will also be obtained by adding half an ounce of sal ammoniac, instead of the spirits of hartshorn. The piece of metal being well cleaned, is to be rubbed with one of these solutions, and then dried by friction with a fresh bmsh. If the hue be found too pale at the end of two or three dajs. the operation may be repeated. It is found to be more advantageous to operate in the sunshine than in the shade. BROWN DYR Upon this subject some general views are given in the article Dteing. explanatory of the nature of this colour, to which I may in the first place refer This dye presents a vast variety of tints, from yellow and red "to black brown and is produced either by mixtures of red, yellow, and blue with each other, or of yellow or red with black, or by substantive colours, such as catechu or oxide of manganese, alone. We shall here notice only the principal shades; leaving their modifications to the caprice or skill of the dyer. 1. Brown from mix-ture of other coloui-s. Wool and woollen cloths must be boiled with one eighth their weight of alum and sulpho-tartrate of iron (see this article) ; afterwards washed, and winced through the madder batli, which dyes the portion of the stuff imbued with the alum red, and that with the salt of iron black ; the tint depending upon the proportion of each, and the duration of the madder bath. A similar brown is produced by boiling every pound of the stuff with two ounces of alum, and one ounce of common salt, and then dyeing it in a bath of logwood contain- ing either sulphotartrate, acetate, or sulphate of iron. Or the stuff may be boiled with alum and tartar, dyed up in a madder bath, and then run throush a black bath of iron mordant and galls or sumach. Here the black tint is added to the red till the proper hue be hit. The brown may be produced also by adding some iron liquor to the madder bath. ^cr the stufi" has been dyed up in it with alum and tartar. A better brown of this land IS obtained by boiling every pound of wool with 2 ounces of alum, dyeing it up in eoebmeal, then changing the crimson thus given into brown, by turning the stuff through 286 BROWN DYE. )« I Ir 1^: the bath after acetate of iron has been added to it. Instead of the cochineal, archil, or cutbear, with a little gaUs or sumach, may be used. ,; . ,. , , Wool or silk may also receive a light blue ground from the mdigo vat, then be mor- ianted with alum, washed, and turned through a madder bath till the wished-for browii be brought out. For the deeper shades, galls or sumach may be added to the paler Brazd- wood with more or less iron mordant. Instead of the indigo vat, Saxon blue may be employed to ground the stuff before dyeing it with madder, or 5 pounds of madder, with 1 pound of alum, a solution of one tenth of a pound of indigo in sulphuric acid, may be used with the proper quantity of water for 20 pounds of wool; for dark shades, some iron mordant may be added. Or we may combine a bath of cochineal or cutbear, fustic, and galls, and add to it sulphate of iron and sulphate of indigo, blunted with a little If we boil woollen cloth with alum and tartar, then pass it through a madder bath, and afterward through one of weld or fustic, containing more or less iron mordant, we obtain shades variable, according to the proportions of the materials, from mordore and cinnamon to chestnut brown. . , - , . r v j After the same manner, bronze colors may be obtained from the union of olive dyes with red. For 25 pounds of cloth, we take 4 pounds of fustic chips, boil them for 2 hours, turn the cloth in this bath for an hour, and drain it ; then add to the bath from 4 to 6 ounces of sulphate of iron, and 1 pound of ordinary madder, or 2 pounds of sandal-wood ; put the cloth again in this compound bath, and turn it through, till the desired shade be obtained. By changing the proportions, and adding an iron mordant, other tinU may be This mode of dyeing is suitable for silk, but with three difieient baths ; one of logwood, one of BrazU-wood, and one of fustic. The silk, after being boiled \i'iih soap, is to be alumed, and then dyed up in a bath compounded of these three decoctions, mixed in the requisite proportions. By the addition of walnut peels, sulphate of copper, and a little sulphate of iron, or by passing the silk through a bath of annotto, a variety of brown shades may be had. . v .v r i Or the silk may receive an annotto ground, and then be passed through a bath of log- wood or Brazil-wood. For 10 pounds of silk, 6 ounces of annotto are to be taken, and dissolved with 18 ounces of potashes in boiling water. The silk must be winced through this solution for 2 hours, then wrung out, dried, next alumed, passed through a bath of BrazQ-wood, and finally through a bath of logwood, containing some sulphate of iron. It Ls to be wrung out and dried. . .. ^. ..v Brown of different shades is imparted to cotton and linen, by impregnating them with a mixed mordant of acetates of alumina and iron, and then dyeing them up, either with madder alone, or with madder and fustic. When the aluminous mordant predominates, the madder gives an amaranth tint. For horse-chestnut brown, the cotton must be galled, plunged into a black bath, then into a bath of sulphate of copper, next dyed up in a de- coction of fustic, wrung out, passed through a strong madder bath, then through the sul- phate of copper solution, and finished with a soap boil. Different shades of cinnamon are obtained, when cottons first dyed up with madder get an oUve cast with iron liquorin a fustic bath. , v j • *v n • • v «v These cinnamon and mordore shades are also produced by dyeing them first ma balli of weld and verdigris, passing them through a solution of sulphate of iron, wringing and drying them; next putting them through a bath containing 1 pound of galls for 10 pounds of stuff, again drying, next aluming, and maddering. They must be brightened by a bod in soap water. , . • . , ■, A suijerior brown is produced by like means upon cotton goods, which have undergone the oiling process of the Turkey red dye. Such stuffs must be galled, mordanted with alum (see Madder), sulphate of iron, and acetate of lead (equal to f of the alum); after washing and drying, dyed in a madder bath, and cleared with a soap bod. The tint of brown varies with the proportion of alum and sulphate of iron. We perceive from these examples, in how many ways the browning of dyes may be modified, upon what principles they are founded, and how we have it in our power to turn the shade more or less toward red, black, yellow, blue, &,c. Brown may be produced by direct dyes. The decoction of oak bark dyes wool a fast brown of different shades, according to the concentration of the bath. The color is more lively with the addition of alum. , The decoction of bastard marjoram {Onganum vulgare) dyes cotton and Imen a red- dish brown, with acetate of alumina. Wool takes from it a dark brown. The bark of the mangrove tree {Eizophara mangle) affords to wool boded with alum and tartar a fine red brown colour, which, with the addition of sulphate of iron, passes into a fast chocolate. . -, .^_ ^r • itr- The Bahlah, the pods of the East Indian Mimom cirurana, and the African Mimota niloticcL gives 'cotton a brown with acetate or sulphate of copper. The raume, Octo^er^^ffn fifT'-' ^'•' ^":*f«»' Germ.) Mr. *T. Mason obtained a patent in firmer mnfV 2 ' /"^P/ovement m the manufacture of this article. It consists in a the br.r Th;f -'"I '^'i^^°'' ^' '™^" '^""^'"^ ""^ ^"^'^ i"t« t^e stock or the handle of «f ro«- • Tk /*'''r ^J ^^^'-^i^? /"-ooves m the stocks of the brushes, for the purpose ?i^hn?SrV^>f ^''^' °^ '^' ^"''' ?^ ^*'^' ^"^^^«d «^ t^^ ^«J^« drilled into the wood^w nr l7ii ,1 K "".r""*? constructions. These grooves are to be formed like a dovetail, or wider at the bottom than the top; and when the ends of the knots of hair have been tLd^^h ^A ^ ^^^ ^^'' "^'^ ^^ P'^'"^'^ outwards into the recess or wider part of tlrl-Hl £-11 ^^ ^^y^t^^'^d-' ^"d thf <^ement and hairs being pressed into the teeth ot threads, will cause them to adhere firmly to the stock or handle of the brush. .n^ /T"^ '"^^ ^^ P'^^^'^ °" t^^ **"t^''^de «f the stock of the brush, if necessary and secured by pms or rivets, or in any other convenient manner, which femdemT; 209 ee also form one side of the outer groove. Fig. 209 is a plan view of the stock of a round brush ; Jig. 210 IS a section of the same ; a o are the dovetailed grooves, which are turned out of the wood ; b is the metal fer- rule ; c c are knots or small bundles of hair, to form the brush. After a number of the knots of hair are prepared, the ends are to be dipped into proper cement, and then placed into the grooves, when their ends are to be squeezed by a pair of pliers, or other means, which will compress them into the oval shape, as shown in Jig. 211 and cause the ends of the hairs to extend ouU ward under the dovetailed part of the recess. The knots of hair are to be successively placed in the grooves, and forced up by a tool against the last knot put in> and so on, until the grooves are filled • /?<>• 211 i« a section taken through a brush with teeth or threads of a screw formed ulVt^eL of the groove; into these teeth or threads the cement and hairs will be forced by the Suttfr' ^^, p^^'^ "^T' '1% ^"^.^" ^'^^ ^'""^y i" th« stock of the brush ^ BUTTER. {Beurre, Fr. ; Butter, Germ.) Milk contains a fatty matter of more Sorit'Tht'"Tt"*^^^'V',7°'r,*i ^''^''^^^ '° '^^ "^ture of the animals which Sr LnJ 1 substance is butter, held suspended in the milk by means of the caseous ^nhfna r 'T ^^^ ^^^^^^ \ »« mUmately blended. Milk is a true emulsion Soi ?l tlT^^' ""T ""i >''r three ingredients, owing its opacity and white 5?i?L. ^- '^'^"'''*'' ^u'°''»^ '^ ""^ ^^*t butyraceous oil. When any circumstance dissolves this union, each component becomes insulated, and manifests itrneculirr properties. Mill^ even left to itself, at a temperature of f^om 50° to 60° F se^^ es na?urrflTf ^ '""'f^ ""'T^ ^^^^ ^ '^^^^^ «^ ^ ^^"^^' ™ore consistLtrbutSer nature floats on its surface, while the subjacent liquid forms a white maema which retains among ite curdy flocks all the whey of the* milk. The upper MaToI- rrelm r/wh:; bl'w.^ "'^'^ ^^ '^^ ^"^^^ ' ^^^ ^ P-^- ---- entS^led^i^^the cm^ '»-! 288 BUTTON MANUFACTURE. It belongs to a work on husbandry or rural economy to treat fully of the operations of the dah-?- one of the principal of which is the extraction of butter from milk. The Tartars and French have been long in the habit of preserving butter, by melting xue iditdiTj ttii^ wherebvare coagulated the albuminous and curdy matters It With a °^« ^^^^ ^ ^^« «"tt^^ ^ (^Vol which the uame^ the button maker may be engraved Fig. 228. is a face view of this die when removed Tand TC'Ju ' ^« i^V«"^^^^^^^« ]V^/ die c. It will be perceived that these dies c and ^together with the punch and bed, compress the disc of metal into the form ISr,?i'/f^'wf ^^'^'^''^°' that shown i^nthefigures, as before stated. Tofth^ shape used for buttons to be covered with Florentine or thin plate metal, in a round ^ell closed m upon the inclined or bevelled edge of the back; . is the cuttLn^nd shaping punch of the shank, which is fixed within the counter die; this punch cute through the njetal of the d^sc, and forms the shank as the dies approach nearer together by raising or forcing it up into the recess or opening in the die c, where it is metl^y tie Jihi T l^- f T"^ P'"''"^-^. ^\'^ ^^ ?^ P"^^^ '^^ ^^i^h compresses the upper part of the shank into the recess g, m the end of the punch .. thereby giving the shank it« rounded figure, and at the same time forming the other part of the sh^k into the Re- quired shape as described at /^rs. 212. to 216. The ends of these shaping punches fit into Jn'l^I'T I. v'S \' J'" -u T'^Jy ^^^ ?^^*"^^^ fig"^^« «^ the punches designed for forming the shank first described. Fig. 229. is a representation of the punches whfn apart and removed out of the dies: fig. 230. is a longitudinal section of the same ; fig. 231 is another view of the punches as seen on the top. The sharp edge of the rece^i in the punch e, comes m contact with the cutting edges of the projecting rib i, of the die c, and thereby cuts through so much of the metal as is required. The edge k of this die keens for'c: nn h' '"'^ of the shank of a spherical figure, al before explalnfd,;hne tL p^^^^^ force up the metal, and form the elevated loop or shank :uu are holes made through the counter die (^ for the passage of clearing pins, which force out the shank or back piece from the counter die when finished ; the operation of which will be shown when describ- ing the machinery hereafter. There are adjusting screws at the back of the punches and dies, by wliich they can be regulated and brought to their proper position one to the other AJthough he has shown the punches which form his improved shanks, fixed into and working m conjunction with the punch and dies which cut out and shape the discs of metal for the back of the button, yet he does not intend to confine himself to that mode of using them, as flat blanks or discs for the backs of buttons may be cut out in a separate stamping press, and afterwards shaped in the same press or in another and then brought under the operation of the punches which form his improved shankk fixed in any suitable press. This last-mentioned mode of producing button shanks and backs he prefers when such metals are employed as require annealing between the operations of shaping the backs and forming the shank. Fig. 232. is a section taken through a pair of dies, in which the operation only of forming the shank is to be performed, the backs being previously shaped m another press. In this instance the punches e aid f Tnl^Z .^''' f."^dtP-^«^« "^ ^'l^^ "^^^^^ I'^^P *^^°^ '"^ the proper position toward each other, «ie die c being mounted in the piece n, and acting against'^the face of the guide m. The blanks or backs of the buttons may be fed into these dies by hand or any other means; and after the shank is formed, the finished back can be pushed out of the lower die by clearing rods passed through the holes u u, and removed by hand or in any convenient manner. •' ^ When his improved shanks are formed out of iron or other metal which is too brittle to allow of the shank being forced up and finished at one operation in the dies and punches, he prefers cutting out and shaping the blank or back of the button first, and l^^l *n«ealing it, to raise or force up the portion of metal to form the shank into the shape shown mfig 233., that is^ without the edges of the metal being turned to prevent their cutting the threads, and after again annealing it, to bend or turfi the edges into the shape shown mfi^. 218 by means of suitable punches in another press, or by a pair of pmcers and punch as shown mfig. 234, which is a side view of a small apparatuTto be 2P2 292 BUTTON. ^i^^^L. used for turning the edges of the shank by hand, with a partly formed shank seen under operation, a, is the upper jaw of a pair of pincers, this jaw being fixed on to the head of the standard 6 ; the under jaw , one or more teeth ; and as the racket-wheel v is fixed on to the end of the axle of one of the rollers I, it will cause that roller to revolve ; and by means of the pair of spur- pinions on the other ends of the axles of the feeding-rollers, they will both revolve simultaneously, and thereby draw down the sheet of metal into the machine. It will be perceived that the standards which support the clearing-plate and guide-bar are car- ried by the axles of the feeding-rollers, and partake of their sliding motion ; also that the clearing-pins o, are made adjustable between the bars p, to correspond with the counter dies. There is an adjustable sliding-stop x upon the bar «, which comes in contact with the back standard t, and prevents the bar s sliding back too far, and con- sequently regulates the quantity of sheet metal to be fed into the machine by the pall and ratchet-wheel, in order to suit different sizes of punches and dies. In case the weight of the bar c, carrying the counter dies, should wear upon its bearings, the guide-pins g g, have small friction-rollers y y, shown under the bosses of this bar, which fnction-rollers run upon adjustable beds or planes « 2, by which means the guide-pins may be partially reUeved from the weight of the bar c,"and the friction consequently diminished- Buttons op Horn.— Mr. Thomas Harris obtained in April, 1841, a patent for im- provements in the manufacture of horn buttons, and in their dies. His invention delates, first, to a mode of applying flexible shanks to horn buttons ; secondly, to a mode of ornamenting horn buttons, by inlaying the front surface thereof; thirdly, to a mode of ornamenting what are called horn buttons, by gilding or silvering their surfaces ; fourthly, to a mode of constructing dies, by applying separate boundary circles to each engraved surface of a die, by which the process of engraving, as well as the forming of accurate dies, will be facihtated ; fifthly, to a mode of constructing dies, used in the 294 BUTTON. manufacture of horn buttons, \rliereby the horn or hoof employed will not be per- mitted to be expressed beyond the circumference of the button. Fig. 242. represents, in section, a pair of dies, a and b, used in producing the 242 S45 250 S54 357 improved horn buttons, according to the first improvement; the upper die a is made to produce the back surfaces of the buttons, and the recess or groove for receiving the flexible shank. Fig. 243. shows, in section and back view, the form of a button nro- duced by the diea . *^ Buttons thus formed are now ready to receive flexible shanks; and if the buttons are to have plain smooth front surfaces, then, in fixing the flexible shanks, the same kind of under die b may be used; but if the front surface of the button is to be em- bossed or ornamented, then, in place of that die a similar one having engraved or suitably ornamented surfaces, is to be used. When fixing the shanks to buttons, the lower or face die, containing the previously formed buttons, is to be heated till a drop of water will nearly boil upon it. ^ The shank is applied as follows:— a metal shell or collet a (Beefig. 244 ) is placed oyer the flexible shank b, and a plate of metal c is laid under the shank- these are placed in the groove or recess of the button, which had been previously heated in the lower die; the upper die a. Jig. 245., is then to be placed on the lower dien, and the two submitted to pressure, until they become cool, when the shank will be firmlv attached, as shown &tfig. 246., and the bottom may be finished in the usual way The second part of the invention, which relates to a mode of ornamenting horn but- tons, by mlaymg the front surface thereof;i8 performed in a manner similar to what has been above descnbed, for fixing flexible shanks, and consists in first forming the front face or surface of a button, in suitable dies, for providing a recess; and then by a second pressure in dies, to fix the ornamental surface ; and, when desired, the surround- ing front surface of the button maj be embossed. Fig. 247. is a longitudinal section of a pair of dies, for forming a recess in the face of a button. Mg. 248. shows, in front view and section^ a horn button, produced by these dies. Mg. 249. shows a metal ornament to be inlaid or fixed in the front surface of the button, but it should be stated that the ornamenting surface, to be fixed in the front surface of the button may be of pearl or other material ; and the size and device varied according to taste. Hg 250 shows in section a i)air of dies, for giving the second pressure for affixing the ornamental surface- and, if desired, the remaining front surface of the button may be ornamented, by ha vine the lower die engraved, or otherwise suitably ornamented. Mg, 251. shows in front view and section a button made according to this part of the invention. The third part of the invention relates to a mode of ornamenting horn buttons, bv gilding or silvermg their surfaces^ -Dus is effected by applying a suitable cementing or adhesive material with a soft brush to the button, in order that gold or silver leaf may be attached to its surface. The cementing or adhesive material preferred to be used is dressing varmsh rendered sufficiently liquid by essence of turpentine • and when the varnish is nearlv dry, gold or silver leaf is applied thereto, and pressed in the same manner as practised when gilding and silvering other surfaces; by thus treating horn buttons, a very novel manufacture of that description of buttons may be produced. The fourth part of this invention relates to the construction of dies used in the manufacture of horn buttons. Mg. 252. is a section of a die, constructed according to BUTTON. 295 this j>art of the invention ; And Jig. 253. is a section showing the die without the bound- ing circles, which confine the pattern ; / is the die engraved at the parts g, g ; around each of which engraved surfaces are circular grooves or recesses to receive the bounding circles, h, h, which fit accurately. B^ the after insertion of these circles, the workman is not confined to move his graver within the bounding line, as that line is not present when engraving the plate; and the graver may pass beyond, and the grooves and the bouudmg circles may readily be made with great accuracy to each of the engraved surfaces. The fifth part of the invention also relates to a mode of constructing dies, for the manufacture of horn buttons, and consists in forming the dies, so that the bounding circle shaU be of a sufficient depth for the counter die to slide within it, and fit acci^ rately in order that the circumference of each button shall be smoothly and accurately formed, i^^. 254. represents in section two dies, and one counter die, made according to this part of the invention ; Jig. 255. shows one of the dies, in plan and section ; and ^g. 256. a plan and section of a counter die, suitable for flexible shank buttons. A, h, are the dies, having the engraved surfaces i, i, on separate circular discs of metaL such as have heretofore been used; J, is a counter die, and k, a tube, within which the counter die is held, the object of this tube being to guide the projecting edges / / of the dies as shown, and thus keep the dies and counter dies correct to each other Fiq 257 is a section of two dies h, and a counter diej; but in this case the tube k is dispensed with, the dies being deeper sunk, and thus guiding the counter die correctly. By the use of these dies, the edges of horn buttons will be more accurately formed, and con- sequently require less finishing. This description of dies may be made according to the mode described in the fourth part of this invention ; that is, by forming the boundary circle separately, as will be understood by referring to Jig. 258., which is a side section of a die complete, with its boundary circle formed in a similar manner to that described above. Mg. 259. represents, in plan and section, a variation in the means of affixing a separate bounding circle to each engraved surface ; and it is suitable for working with- out the tube. In using these dies they are to be heated but slightly, whether for buttons with metal shanks, or to receive flexible shanks, and are to be pressed as here- tofore. The patentee claims, firstly, the mode of manufacturing horn buttons with flexible shanks, by first forming buttons by pressure and heat, and then by a second pressure in dies, to affix flexible shanks thereto, as above described. Secondly, the mode of ornamenting horn buttons, by causing suitable surfaces to be affixed in the front surfaces, by pressing the buttons with the ornaments in dies, as above described. Thirdly, the mode of ornamenting horn buttons by gilding and silvering their surfaces as described. Fourthly, the mode of constructing dies used in the manufacture of horn buttons, by applying separate bounding circles to each engraved surface for a button • and fifthly, the mode of manufacturing horn buttons in dies, wherein the horn or hoof is prevented from being expressed at the circumference of the buttons as described. Buttons, Covered. Mr. Joseph Parkes obtained, in 1840, a patent for improve- ments in the manufacture of covered buttons made by dies and pressure, by the application of horn as a covering material The process resorted to by the patentees for carrying out this invention, is very similar to that pursued in manufacturing Florentine buttons ; such modifications being applied as are rendered necessary for adapting such process to the peculiar nature of the material employed for covering the face of each button, a, fig. 260. shows a plan of a disc of iron plate, with four projecting points, which is formed by suitable dies in a fly-press, as is well under- stood; the points are then turned down, and the disc a, is sunk into the shape shown at Jig. 261., and two such sunk discs are applied to the internal core of the button-board of each button ; b, Jig. 262., shows a plan and edge view of a circular disc of button-board, suitable for forming the internal core of a button. The dies being placed in suitable presses, as is well understood in using similar dies in manufacturing Florentine or other covered buttons, one of the sunk dies a is placed in the under die, with the points upwards, having a disc of button-board placed on the points, as shown at Jig 263. ; the upper die or punch is then caused to descend and press the button board b into the shape shown &tjig. 264. ; which, when thus formed, is to have a die a, applied on the other side, as shown at *Jig. 265. The disc a, to be next fixed to the button-board, is placed in a suitable die, the disc which has already been fixed being upwards ; the die or punch is now to be pressed down, which will produce the button-board, with the discs a a on either side, into the shape* shown at/^r. 266. ; and it will be seen, that one of the discs will, by the shape of the die be sunk concave, whilst the other disc a, on the other side, will be formed convex, or according to the figure of the face of the intended button. The core of button-board, /g^r. 266., is now ready for being inserted into the fabric which IS to become the flexible shank of the button, and which flexible shank is formed by smking a portion of fabric in suitable dies, as is well understood when making 296 BUTTON. Uif button h«' ^7 Florentine or other covered buttons; and the shank being so sunk, the button-board or core,>5r. 266., is to be placed thereon, with the concave surface 63 6 «M7 S70 871 S73 inserted into the metal shell cL 268 and fl ''''''^'^'I'S the core, which Is next are pressed together, and the paftlv mkn,^L? /w. ^"''^^ P^*'"^ ^° * suitable die, consisting of the shank contafnEL^^^ ^^^•' ^^" ^^ produce J shell c, which, by the die has Tff P^tlT' T?'"*'^ ""^ ^^ ^^°* surface with the met2 The bitton, thus for fo^Seris now fr^^^^^ Tt^' ^"^"V^ ^^' ^'''^^' «^««k. horn, which is performeTfnlhe fXwingTannr-^^^^^^^^^^ %""° i'i\^^ ^^ cut out by suitable dies, the ciroumfJZnr^u^^^^^' V^:' ^^^^* * ^^^ ^f horn, over the m^ould,/,. 26? tt hTn^mlrnot be P^^^^^^^^^ ^^^f Ih^' " '^^lS for affixing the covering of horn to the bntfnn ?v.! « n^ , *.^'^?' 271., shows a collet, his hand to rest for a verv short Urn^ „„ tlf" *""*"* *¥ ""e workman can just boar at ;j^*. 273 and 274. which consist of fh! f k ^^^^^J^t^o^^^cjion of the parte shown edge of the tube i is made beUr^^^^^^^^^^ ^""^ V^ ^^" P"^"^ ^^ ^'^ / The lower pressed on the back oTthe bu toTlnd 1^^^ *" '^"f" >^" '"^"^P"^ ^^^^^ <^o »>« forced through the horn in the bSLn .n:^ -'^ ""• P^.f^ "^ *' ^^ "^"^ *'^^ ««"et to b« the tube I, which wS punch is wVfr^^-'rtK^i'''^P*^^^ *^" "^"^* ie placed ia figure represents the die /Z punch A ?n f h ^".-l-" *' ^ '^^r^ ?.* >^- ^^^-^ which forced the parte into the die g and tht fi ^^ond^t^on just described, after having and the puSch or die j placed'in ?h A K ^"'%*^ n t"""^' *^" ^"^^ ^ ^'^^ * «^"et I the pressure of the puuXh wtr ^^^^^^ *°" *^"^g« «^« ^^ » ^o-^^i^ion to receive die J, before the hom has Ln UdeLl^ wu * ^^P^e8s^re coming on the punch or over the die or punch? conL^uentlv IT ^^i*''^ ^""^t ^ ^>' ^^"^^ ^^"^^ ^ ^« pl««e "■» ^'^^iyTenM or oi naraented die the polishing is not necessary. The button being thus made i« f^ „o^t.Tdl:semptyeTltrsetrer„l^^^^^^ used in the manufacture orothL7ov^edbutt„*^ I^"^/""'!"" '''*!,''»™g been before so loni? as the n«..nli„.. „!...* ^"Terea buttons ; nor does he confine himself thereto. manXTurin/covered t» ""!? T""."-" "' '^e invention be retained ; viz. that of .TeerWn"r§i:rv:fnglat:^iar HeXtlth^^^^^^^^ 'V" Tl'^'"" "^r*"" rin«coveredbuttonsbytgeappU:aiio?:ftr^:rvt:i--X^^^ taberrces aW o^e tW,^™fV- T'"1\*5' """^ "« "> !>» ""de, with swells or prZ are we?ded to^^Hr .1. f ^'''*"" '^8:"' '*''"" "^"^ »f *eir ends, so that when these tt" Tuttleaf^fn^ 'Suoh -h'^"'';^P''*k "^ *' '^ ''<'*^ ^--^ *« dicker at the ends of •ny other meLr^ Wh.^ ?.. f ^? "''7/ 5'*. *^"™<''^ "' """^ by rolling, swa^^ing, or .tr{t:Wfi"edS,os^tt"'ml'ddl':'^ " "^'''''' '* ""^ "" ^'-gtbened, ly a tfaef'or to Martinimfo and (^,^«?1 ' ""^^ '5P|!^^"- ^^-^^^^ ^ ^^^^^^ ^^ ^^is ship from En&and a^ohorpHn^lf ,^- ^"?^*^«"Pe and home again, in the course of four months, having h?8 rkk Z7ll?-'T T'^ ^^"jty of gromxd without any accident. He muSed cab eT not nn?vr''^ '''*^"' P'^t '^* ^^^^ °^^g^<^ ^^ substituted for hemp in mak S nh« n^ n ? ^ ^T ™««"?g vessels, but for the standing rigging. Since this per of ?he tw^.^H 1-^T''' ^T "S^^'T«"y introduced into aU the shi|t of the ^yal nav^^^ materialTf t'ie"l?e,?oI;»ir'''^r'^ '"• ""=• '"r^^<'t"^^' of iron cable is, to p««ure . Tain In order L o^?,^! ^' ^"^ '" """« "- "'^"J"' '» ''«<'? '" ^'^ the direction of the theTik^ltbe'^ptm Sr^:?^^^^^^^^^^^ - ^^ ^"^ ^-' '- <>' 278 H ^ i.et A B,jiff 278., be a circular link or ring, of one inch rod iron the rrouaronl'-r^ "''^.^ ring being islnches, and the inner 9 c D nnlHn?^ f ^ ^T^' be applied to the two pointe of the link thP C«^ ^^^yd^ E, and D towards f, the result will be, when lil/n '' ^^ffieiently intense, that the circular form of the link n«r«n!i ^'T^^'^ '°^*' ^''^*^^'' ^«™ wit^ tw« round ends and two iWnr ^^\'^ seen m /^. 279. The ratio of the exterior to the Wpr t£'"P^''^'' I^'t ^^« originally as 15 to 9, or 5 to 3, is no longer the same in Aa. 279. Rpn^^ th^rZ. w;ii k^ . U..„,.^..„.' .... • Vol. L — V lonrro,. ♦v.V "^ ••" ^ ^" **"" "I igiuaiiy as 10 lo y, or 5 to 3, is no ■S^!3! 1 ^^ same in /^. 279. Hence there will be a derangement in JSfJthe relative position of th^ nnmT.«,,^«f ^„.*:.i.„ „.,^ °,^. / .. — ^ their cohesion In Jiff. 278. the segment m n of the outside periphery teing hhJ^r. 1 *• ^..J'y' ^'^' -neuce mere win De a derangement in tl.!,V ! k""®- Position of the component particles, and consequently their cohesion will be progressively impaired, and eventually d^ siroyed. in fig. 278. the segment m n of the outside periphery being •^JT.Ti/': 298 CABLE. "^lual to 3 inches, the corresponding inside segment will be | of it, or 1 * inches. If Ais portion of the link, in consequence of the stretching force, comes to be extended into a straight line, as shown in fig. 279, the corresponding segments, interior and exterior, must both be reduced to an equal length. The matter contained in the 3 inches of the outside periphery must therefore be either compressed, that is, condensed into 1|. inches, or the inside periphery, which is only ]1 inches abready, must be extended to 3 inches ; that is to say, the exterior condensation and the interior expansion must take place in a reciprocal proportion. But, in every case, it is impossible to effect this con- traction of one side of the rod, and extension of the other, without disrupture of the link. Let us imagine the outside periphery divided into an infinity of points, upon each of which equal opposite forces act to straighten the curvature : they must undoubtedly occa- sion the rupture of the corresponding part of the internal periphery. This is not the sole injury which must result ; others will occur, as we shall perceive in considering what passes in the portion of the link which surrounds c n^fig. 279, whose length is A\ inches outside, and 2LL inside. The segments m p and n o, fig. 278 are actually reduced to semi-circumferences, which are inside no more than half an inch, and outside as before. There is thus contraction in the interior, with a quicker curvature or one of shorter radius in the exterior. The derangement of the particles takes place here, in an order inverse to that of the preceding case, but it no less tends to diminish the strength of that portion of the link; whence we may certainly conclude that the circular form of cable Jinks is an extremely faulty one. Leavmg mtUers as we have supposed vafig. 278, but suppose that g is a rod introdnced mto the mail, tUidering its two opposite points a b from approximating. This circum- 280 stance makes a remarkable change in the results. The link puUed as above described, must assume the quadrilateral form shown in fig. 280. It offers more resistance to deformation than before ; but as it may still suffer change of shape, it will lose strength in so doing, and cannot therefore be recommended for the construction of cables which are to be exposed to very severe strains. Supposing still the link to be circular, if the ends of the stay comprehended a larger portion of the internal periphery, so as to leave merely the space necessary for the plan of the next link, there can be no doubt of its opposing more effectively the change of form, and thus rendering the chain stronger. But, notwithstanding, the circular portions which remain between the points of application of the strain and the stay, would tend always to be straightened, and of consequence to be destroyed. Besides, though we could construct circular links of sufficient strength to bear all strains, we ought still to reject them, because they would consume more materials than links of a more suitable form, as we shall presently see. The effect of two opposite forces applied to the links of a chain, is, as we have sees, to reduce to a straight line or a straight plane every curved part which is not stayed : whence it is obvious that twisted links, such as Brown first employed, even with a stay in their middle, must of necessity be straightened out, because there is no resistance in the direction opposed to the twist. A cable formed of twisted links, for a vessel of 400 tons, stretches 30 feet, when put to the trial strain, and draws back only 10 feet. This elongation of 20 feet proceeds evidently from the straightening of the twist in each link, which can take place only by impairing the strength of the cable. From the preceding remarks, it appears that the strongest links are such as present, in their original form, straight portions between the points of tension ; whence it is clear that links with parallel sides and round ends would be preferable to all others, did not a good cable require to be able to resist a lateral force, as well as one in the direction of its length. Let us suppose that by some accident the link^^. 279. should have its two extremities 281 >^^Sv pulled towards y and z, whilst an obstacle x, placed right opposite to its middle, resisted the effort. The side of the link which touches x would be bent inwards ; but if, as in^^. 281., there is a stay a o b, the I two sides would be bent at the same time ; the link would notwith- standing assume a faulty shape. In thus rejecting all the vicious forms, we are naturally directed to that which deserves the preference. It is shown in^^. 282. This link has a cast-iron stay with large ends ; it presents in all directions a great resistance to every change of form ; for let it be pulled in the direction a 6, Wgainst an obstacle c, it is evident that the portions d e 'and d f, which are supported by the parts ff e and a f cannot get deformed or be broken without the whole link giving way. As the matter composing g e and gf cannot be shortened, or that which composes d e and df be lengthened, these four sides will '^m 283 -v.,^-.>-^. CABLE. 299 remain necessarily in their relative positions, by virtue of the large-ended stay K whose pronle is shown mjig. 283. We have examined the strength of a link in every di- rection, except that perpendicular to its plane. Fig. 284. represents the assemblage of three links in the above B predicament ; but we ought to observe, that the ob- stacle c, placed between the links a b, must be neces- sarily very small, and could not therefore resist th« pressure or impact of the two lateral links. , ,. Process of manufacturing iron cables. — ^The imple- ments and operations are arranged in the following order- *i. 1- ^/«^«^!?f atory furnace (see Iron), in which a number of rods or round bars of the best possible wrought-iron and of proper dimensions, are heated to bright ignition. 2. The cutting by a machine of these bars, in equal lengths, but with opposite bevek o ?.u V ?• ^^^T'*^ crossing and shcing of the ends in the act of welding. 3. Ihe bending of each of these pieces by a machine, so as to form the Unks : th« last two operations are done rapidly while the iron is red-hot 4. The welding of the links at small forge fires, fitted with tools for this express pur pose, and the immediate introduction of the stay, by means of a compound lever pJess 5. Proving the strength of the cables by an hydraulic press, wofked by two mei turning a wmch furnished with a fly wheel. j iu« ■nie furnace is like those used in the sheet-iron works, but somewhat larger, and needs no particular description here. * Figs.2%6. and 286. are a plan and elevation of the shears with which the rods are cut into equal pieces for forming each a link. It is moved at Mr. Brunton's factory by a smal steam engine, but, for the sake of simplicity, it is here represented woried by foui frL"i;^nHi*i^''yr'' ^V* ?t^v ^ ''' ^°^ establishment. These must be relieved howev« on.T«3^. "^ ^'"' ' ^t'^.''^ ^*^^ «^^*^'^' machine is calculated to require nearly b:L^rfratl^Wd^^^^^ ^^^ ^^^^^ ^^ ^'^^^^ ^^ ^^^ neighbourhood of A and b are the two cast-iron limbs of the shears. The first is fixed and th'. kjcouc. 2Q2 300 CABLE. IB moveaWe by means of a crank shaft c; driven by a heavy fly-wheel weighing 7 or 8 cwt The cutting jaws g are mounted with pieces of steel which are made fast by bolts, and may be changed at pleasure. E, the bar of iron to be cut. It is subjected, immediately upon being taken out of the fire, to the shears, xmder a determinate uniform angle, care being taken not to let it turn round upon its axis, lest the planes of the successive incisions should become unequal. F 18 a stop which serves to determine, for the same kind of chain, the equality of length in the link pieces. Figs. 287, 288, 289, plan and elevations of the machine for bending the links into an elliptic form. It is represented at the moment when a link is getting bent upon iL 288 A is an elliptic mandrel of cast-iron ; it is fixed upon the top of a wooden pillar B, solidly supported in the ground, c is the jaw of the vice, pressed by a square- headed screw against the mandrel a. D part of the mandrel comprehended between x and t, formed as an inclined plane, so as to preserve an interval equal to the diameter of the rod between the two surfaces that are to be welded together. E rectangular slots (shears) passing through the centre of the nut of the mandrel, in which each of the pins f may be freely slidden. G horizontal lever of wrought-iron six feet long. It carries at h a pulley or friction- roller of steel, whose position may be altered according to the diameter of the links. It is obvious that as many mandrels are required as there are sizes and shapes of links. The piece of iron intended to form a link being cut, is carried, while red-hot, to the bending machine, where it is seized with the jaw of the vice c, by one of its ends, the slant of the cut being turned upwards ; this piece of iron has now the horizontal direc- tion m n ; on pushing the lever g in the line of the arrow, the roller n will force mnto be applied successively in the elliptic groove of the mandrel : thus finally the two faces that are to be welded together will be placed right opposite each other. The length of the small diameter of the ellipse ought to exceed by a little the length of the stay-piece, to allow of this being readi y introduced. Tlie difference between the points f, e, is equal to the difference of the radii vectores of the ellipse. Hence it will be always easy to find the eccentricity of the ellipse. JPlg. 290 is a lever press for squeezing the links upon their stays, after the links are welded. This machine consists of a strong cast-iron piece a, in the form of a square, of which one of the branches is laid horizontally, and fixed to a solid bed by means of bolts ; the other branch, composed of two cheeks, leaving between them a space of two CABLE. 801 incnes, stands upright. These two cheeks are united at top, and on the back of their plane by a cross piece b. c, a rectangular staple, placed to the right and led of the cheeki through which is passed the mandrel d, which represents and keeps the place of the fol- lowing link. E, is a press lever, 6 feet long, f, clamp and counterclamp, between which the link is pressed at the moment when the stay is properly placed. There are other clamps, as well as staples c, for changing with each changed dimension of links. The links bent, as we have seen, are carried to the forge hearth to be welded, and to re- ceive their stay ; two operations performed at one heatmg. Whenever the welding is finished, while the iron is still red-hot, the link is placed upright between the clamps r; then a Workman introduces into the staple the mandrel d, and now applies the stay with a pair of tongs or pincers, while another workman strikes down the lever e forcibly upon It. This mechanical compression first of all joins perfectly the sides of the link against the concave ends of the stay, and afterwards the retraction of the iron on cooline mcreases still more this compression. If each link be made with the same care, the cable must be sound throughout. It IS not delivered for use, however, till it be proved by the hydrauhc press, ai a draw-bench made on purpose. The press is a horizontal one, having the axis of its ram in the middle line of the draw-bench, which is about 60 feet long, and is secured to the body of the press by strong bolts. The portion of chain under trial, being attached at the one end to the end of the ram of the press, and at the other to a cross-bar at the extremity of the draw-bench, two men put the press in action, by turning the winch, which works by a triple crank three forcing pumps alternately; the action being equalized by means of a heavy fly-wheeL As long as the resistance does not exceed the force of two men, the whole three pumps are kept in play. Aflter a while one pump is thrown out of gear and next another, only one being worked towards the conclusion. The velocity of the ram being relaided first one thurd and next two thu-ds, gives the men a proportional mcrease of mechanical power. The strength of two average men thus applied being computed, enables us to know at every instant the resistance opposed by the chain to the pressure of the ram. The strain usually applied to the stronger cables is about 500 tons. The side beams of the draw-bench are of cast-iron, 6 inches in diameter ; the dif- ferent pieces composing it are adjusted to each other endwise by turned joints. Props also of cast-iron support the beams two feet asunder, and at the height of 30 inches above the ground. The space between them is filled with an oak plank on which th« trial chain is laid. btrengtn of iron cables compared to hemp cables : Iron Cables. Diameter of Iron Rod. Hemp Cables. Circumference of Rope. Resistance. IncJus. Inc?ies. Tons. 0| 9 12 1 10 18 1* 11 26 li 12 32 1 5 13 35 14 to 15 88 u 16 44 If 17 62 li 18 60 ll 20 70 2 22 to 24 80 It would be imprudent to put hemp cables to severer strains than those indicated in the preceding table, drawn up from Brunton's experiments; but the iron cables of the above sizes wiU support a double stram without breaking. The) ought never in com- mon cases, however, to be exposed to a greater stress. A cable destmed for ships of a certain tonnage, should not be employed m those of greater burden. Thus treated it may be always trusted to do its duty, and will last longer than the ship to which it be- longs. A considerable part of this decided superiority which iron cables have over hemp ones, is undoubtedly due to the admirable form contrived by Brunton. Repeated experunents have proved that his cables possess double the strength of the iron rods IvLT '^ • ^? ^'^ made -a fact which demonstrates that no stronger fonn can be aevised or is m fact possible. ° \J!^^A- ^i'^°''i'* ^^^^h\e qualities of iron cables is their resisting lateral as weU as lo^tudmal strains, as explained under Jigs. 219 and 221. Vessels furnished with such cables have been saved by them from the most imminent 3oa CADMIUM. CALCroM. 303 peril. The Henry, sent out with army stores during the peninsular war, was caught on the northern coast of Spain in a furious storm. She run for shelter into the Bay of Biscay among the rocks, where she was exposed for three days to the hurricane. She possessed fortunately one of Brunton's 70 fathom chain cables, which held good all the time, but it was found afterwards to have had the links of its lower portion polished bright by attrition against the rocky bottom. A hemp cable would have been speedily torn to pieces in such a predicament. In the contracts of the Admiralty for chain cables for the British navy, it is stipulated /hat " the iron shall have been manufactured in the best manner from pig iron, smelted from iron-stone only, and selected of the best quality for the purpose, and shall not have received, in any process whatever subsequent to the smelting, the admixture of either the cinder or oxydes produced in the manufacture of iron ; and shall also have been puddled in the best manner upon iron bottoms, and at least three times sufficiently drawn out at three distinct welding heats, and at least twice properly fagoted." The following is a table of the breaking proof of chain cables, and of the iron for the purpose of making them, also of the proofs required by her majesty's navy for chains. Size of Bolt. Proof of Bolt. Proof of Chain. Navy Proof of Chain. Inches. TOTU. Cwt. Tons. Ciot. Tons. k 5 7 8 11 4| 1 8 7 13 4 12 1 19 6 10| i 16 4 26 6 13| 21 8 34 5 18 1| 27 2 48 15 22f 1| 33 10 53 11 281 ]| 40 10 65 34 1 48 4 77 40| 1 56 11 90 10 47| 1 65 12 105 5H If 75 6 120 10 63i 2 85 14 137 72 21 96 15 1.55 81J In Brunton's cable the matter in the link is thrown very much into one plane ; th« link being of an oval form, and provided with a stay. As there are emergencies in which the cable must be severed, this is accomplished in those of iron by means of a bolt and sheckle (shackle), at every fathom or two fathoms ; so that by striking xjut this bolt or pin, this cable is parted with more ease than a hempen one can be cut. CACAO, BUTTER OF. See Cocoa, and Oils, Unctuous. CADMIUM is a metal discovered about the beginning of the year 1818. It occurs chiefly in Silesia in several ores of zinc ; and may be readily recognised by means of the blowpipe ; for at the first impression of the reducing or smoky part of the flame, the ores containing cadmium stain the charcoal all round them with a reddish yellow circle of oxyde of cadmium. The Silesian native oxyde of zinc contains from 1 J to 11 per cent, of cadmium. The cadmium may be extracted by dissolving the ore in sulphuric acid, leaving the solution acidulous, and diluting it with water, then transmitting through it a stream of sulphureted hydrogen, till the yellow precipitate ceases to fall. This powder, which is sulphuret of cadmium, is to be dissolved in concentrated muri- atic acid, the excess of which is to be expelled by evaporation ; and the muriatic salt being dissolved in water, carbonate of ammonia is to be added in excess, whereby the cadmium separates as a carbonate, while the small portion of adhering copper or zinc is retained in solution by the ammonia. Herapath has shown, that in distilling zinc per descensum (see Zinc), the first portions of gaseous metal which are disengaged burn with a brown flame and deposite the brown oxyde of cadmium. Cadmium has the color and lustre of tin, and is susceptible of a fine i>olish. Its fracture is fibrous ; it crystallizes readily in regular octahedrons, and when it suddenly solidifies, its surface gets covered with fine mossy vegetations. It is soft, easily bent, filed, and cut, soils like lead any surface rubbed with it. It is harder and more tena- cious than tin, and emits a creaking sound when bent, like that metal. It is very ductile, and may be drawn out into fine wire, and hammered into thin leaves without cracking at the edges. Its specific gravity, after being merely melted, is 8*604 ; and 8-6944 after it has been hammered. It is very fusible, melting at a heat much under redness ; indeed, at a temperature little exceeding that of boiling mercury, it boils and distils over in drops. Its vapors have no smell. It is but slightly altered by exposure to air. "When heated in the atmosphere, it readily takes fire, and burns with a brownish yellow smoke which is destitute of smell In strong acids it dissolves with disengage- ment of hydrogen, and forms colourless solutions. Chromate of potash causes no pre- cipitate in them, unless zinc or lead be present. There is only one oxide of cadmium, the brown above mentioned. Its specific gra- vity is 8*183. It is neither fusible nor volatile at a very high temperature. When in the state of a hydrate it is white. The oxide of cadmium consists of 87 "45 parts of metal, and 12'55 oxygen in 100 parts. Berzelius states its atomic weight to be 55*833 to hydrogen 1 '000. Its sulphuret has a fine orange yellow colour, and would form a beautiful pigment, could the metal be found in sufficient quantity for the purposes of art The sulphate is applied to the eyes by surgeons for removing specks of the cornea. CAFFEINE. A chemical principle discovered in cofi'ee, remarkable for containing much azote. See Coffee. According to Robiquet the proportion of caffeine in 1000 of coffee is as follows ; Martinique 6*4, Alexandrian 4*4, Java 4*4, Mocha 4, Cayenne 3*8, St. Domingo 3*2. It is probable that 0*64 per cent, is an ordinary proportion. According to Liebig, the proportions are per lb., Martinique 32 gr., Alexandrian 22, Java 22, Mocha 20, Cayenne 19, St Domingo 16. H. J. Vereman of Lubeck mixes 10 lbs. of bruised raw coffee with 2 of caustic lime, made previously into hydrate ; treats the mixture in a displacement apparatus with alcohol of 80° till the fluid which passes through no longer furnishes evidence of the presence of caffeine. The coffee is then roughly ground and brought nearly to the state of a powder, and the refuse of the once digested mix- ture from the displacement apparatus, dried and ground again, and mixed with hydrate of lime, is once more macerated. The grinding is more easily effected after the coffee has been subjected to the operation of alcohol, having lost its horny quality, and the caffeine is thus more certainly extracted. The clear alcoholic liquid thus obtained is then to be distilled, and the refuse in the retort to be washed with warm water, to separate the oil. The fluid is now evaporated into a crystalline mass, filtered and expressed. The impure caffeine is freed from oil by pressure between folds of blotting paper, purified by solution in water with animal charcoal, and is thus obtained in shining white silky crystals. In general not more than 3 drams were procured from 5 pounds of coffee, from 10 pounds 7 drams, and from 100 pounds the largest quantity, viz. 6 ounces and 4 scruples of caffeine ; a proof that a large quantity must be operated upon, if in a quantitative respect a satisfactory result is to be obtained. Thus it is seen that good Brazilian coffee contains 0*57 per cent, of caffeine. At the same time it may be observed that it contains about 10 per cent, of a green liquid oil, and 2 per cent, of a yellow solid fat. CAJEPUT OIL is obtained from the leaves of the tree called Melaleuca Leuca- dendron by Linnajus, which grows upon the mountains of Amboyna, and in other of the Molucca islands. It is procured by distillation of the dried leaves along with water, is prepared in great quantities m the island of Banda, and sent to Holland in copper flasks. Hence as it comes to us, it has a green colour. It is very limpid, lighter than water, of a strong smell resembling camphor, and pungent taste like cardamoms. When rectified the copper remains in the retort, and the oil comes over colourless. It is used in medicine as a stimulant. See Oils, Etuereous. CALAMANCO. A sort of woollen stuff of a shining appearance, chequered in the warp, so that the checks are seen only upon one side. CALAMINE. A native carbonate of zinc. See Zinc. CALCAREOUS EARTH. {Terre calcaire, Fr. ; Xalkerde, Germ.) Commonly denotes lime, in any form ; but, properly speaking, it is pure lime. CALCAREOUS SPAR. Crystallized native carbonate of lime. CALCEDONY. A hard mineral of the siliceous family, often cut into seals. Under it may be grouped common calcedony, heliotrope, chrysoprase, plasma, onyx, sardonyx, and sard. CALCHANTUM. The ancient name of native copperas or sulphate of iron. CALCINATION, is the chemical process of subjecting metallic bodies to heat with access of air, whereby they are converted into a pulverulent matter, somewhat like lime in appearance, called calx in Latin. The term calcination, however, is now used when any substance whatever is exposed to a roasting heat. CALCIUM. The metallic basis of lime. See Lime. The atomic weight of this element being an important point, both as to pure chemistry and the chemical arts, has been the subject of innumerable researches. Very lately Berzelius, in the Annalen der Chemie und Phamiacie, xlvl p. 241., has collated the most recent results of the analysis of other philosophers with his own ; and while Dumas, Marchand, and Erdmann estimate the weight at 20, that of hjdrogen =. 1, or 250 oxygen = 100, he finds it ought to be, as compared with the latter, 2519 ; and to the former, 20,152. 304 CALENDER. CALENDER. 305 CALC-SINTER. The incrastations of carbonate of lime upon the ground, or the pendulous conical pieces called stalactites, attached to the roofs of caverns, ait so called. CALC-TUFF. A semi-hard, irregular deposite of carbonate of lime, formed from the waters of calcareous springs. CALCULUS. The stony-looking morbid concretion, occasionally formed in the bladder of urine, gall-bladder, cystic duct, kidneys, and other parts of living animals. Its examination belongs to medical chemistry. CALENDER (Calandre, Fr. ; Kalander, Germ.), a word derived from the Greek kalindros ( cylinder), is the name of a machine, consisting of two or more cylinders, revolving so nearly in contact with .each other that cloth passed through between them is smoothed, and even glazed, by their powerful pressure. It is employed either to finish goods for the market, or to prepare cotton and linen webs for the calico-printer, by rendering their sur- faces level, compact, and uniform. This condensation and polish, or satinage, as the French call it, difler in degree according to the object in view, and may be arranged into three distinct series. 1. For goods which are to receive the first impression by the block, a very strong pressure is required ; for, upon the uniformity of the polish, the neatness and regularity of the printing, and the correspondence of its members, depend. In many establishments the calico is passed twice through the calender before being sent to the tables. 2. The pieces already dyed up at the madder bath, or otherwise, and which remain to be filled in with other colors, or grounded-in, as it is technically styled, must receive a much less considerable gloss. This is a principle everywhere admitted and acted upon, because the outline of the figured design being deranged by the washing, and sometimes in consequence of the peculiar texture of the cloth, the printer, in order to apply his grounding blocks properly, and to fit them to the contours of the figures already impressed, is obliged to stretch the piece sometimes in the direction of the warp, and sometimes of the weft, which would be impossible if they had been hard glazed by the calender. 3. The degree of glazing given to finished goods depends upon the taste of purchasers, and the nature of the article ; but it is, in general, much less than for the first course of block-printing. The most complete calender probably in existence is that used by some of the eminent calico-printers of Alsace, as contrived by M. Charles Dollfus, and constructed by MM. Witz, Blech, and Co. 1. It passes two pieces at once, and thus does double the work of any ordinary machine. 2. It supersedes the necessity of having a workman to fold up the goods, as they emerge from the calender, with the aid of a self-acting folder. 3. It receives, at pleasure, the finished pieces upon a roller, instead of laying them in folds ; and, by a very simple arrangement, it hinders the hands of the workmen from being caught by the rollers. Calenders, in consequence of the irregular demand for foreign orders and shipments, are worked very irregularly, being sometimes overloaded with duty, and at others alto- gether unemployed. A machine which can, when required, turn out a double quantity of goods, must, therefore, be a desirable possession. For the first course of the printers, where high calendering is necessary, the goods are usually passed twice through be- tween two paper cylinders, to give that equality of surface which could not be obtained by one passage, however strong the pressure ; and therefore the simplification of this calen- der will prove no economy. Besides, in order to increase the pressure to the requisite de- gree, the cylinders would need to be made bulging at their middle part, and with such cylinders common smoothing could not be given ; for the pieces would be glazed in the central line, and rough towards the edges. For pieces already printed in part, and re- quiring only to be grounded-in for other colors, the system of double effect has fewer ob- jections, as a single passage through the excellent calender described under Bleaching, page 140, is found to answer very well. The most remarkable feature of M. Dollfus's machine is its being managed by a single workman. 5?x or eight pieces are coiled upon the feed-roller, and they are neither pasted nor stitched together, but the ends are merely overlapped half a yard or so. The workman is careful not to enter the second piece till one third or one half of the first one has passed through on the other side, to prevent his being engrossed with two ends at a time. He must, no doubt, go sometimes to the one side, and sometimes to the other of the machine, to see that no folds or creases occur, and to be ready for supplying a fresh piece as the preceding one has gone through. The mechanism of the folder in the Alsace machine is truly ingenious : it performs extremely well, really saves the attendance of an extra workman, and is worthy the attention of manufacturers intent upon economizing hand labor. The lapping-roller works by friction, and does its doty fully better than similar machines guided by the hand. The numerous accidents which have happened to the hands of workmen engaged in calenders should direct the attention towards its effective contrivance for preventing such misfortunes. These various improvements in the Alsace machine may be easily adapted *o the ordinary calenders of almost every construction. I \ a The folder is a kind of cage, in the shape of an inverted pyramid, shut on the tour sides and open at top and bottom ; the top orifice is about five inches, the bottom one an inch and a half; the front and the back, which are about four feet broad, are made of tin-plate or smooth pasteboard, and the two sides are made of strong sheet-iron ; the whole oeing bolted together by small bars of iron. Upon the sheet-iron of the sides, iron up- •-ights are fixed, perforated with holes, through which the whole cage is supported freely bv njeans of studs that enter into them. One of the uprights is longer than the other, and bears a slot with a small knob, which, by means of the iron piece, joins the guide to the crank of the cylinder, and thereby communicates to the cage a seesaw movement ; at the bottom extremity of the great upright, there is a piece of iron in the shape of an anchor, which may be raised, or lowered, or made fast, by screws. At the ends of this anchor are friction-rollers, which may be drawn out or pushed back and fixed by screws; these rollers lift alternately two levers made of wood, and fixed to a wooden shaft. The paws are also made of wood : they serve to lay down alternately the plies of the cloth which passes upon the cage, and is folded zigzag upon the floor, or upon a board set below the cage ; a motion imparted by the seesaw motion of the cage itself. See Stretching Machine. To protect the fingers of the workmen, above the small plate of the spreading-board or bar, there is another bar, which forms with the former an angle of about 75" ; they come sufficiently near together for the opening at the summit of the angle to allow the cloth to pass through, but not the fingers. See Bulletin de la Sociele IndusiritUe de Mulhauseriy No. 18. I shall now describe, more minutely, the structure of the powerful but less complicated calender mechanisms employed in the British manufactories. A front elevation of a four-rollered calender (five rollers are often introduced) for gla- ring goods is given in^g. 293. d I are two pasteboard or paper cylinders, each 20 inched 293 291-^ m diameter, whose structure will be presently described : / is a cast-iron cylinder turned perfectly smooth (its fellow is often placed between e and d) : it is eight inches in diame- ter outside, four inches inside, with two inches thickness of metal, e is another paste- board cylinder, fourteen inches in diameter: the strong cast-iron frame contains the bush- es in which the journals of the rollers turn, op, is one of the pair of levers for commu- nicating a graduated pressure according to the quality of the goods. Figs. 292, 293, are end views of the same machine to show the working gear. The wheel s, on the end of the upper iron cylinder, is ten inches in diameter; that on the end of the fellow iron cylinder below (when it is present) is thirteen inches ; both are connected by the larger carrier wheel /. The lower wheel u is one third larger than the upper wheel, and therefore receives from the carrier wheel /, a proportionally slower motion, which it imparts to the central pasteboard roller «, lying upon it, causing it to move one third more slowly than the upper pasteboard roller. Thus a sort of sliding motion is produced, which, by rubbing Iheir surfaces, glazes the goods. The iron rollers are made hollow for the purpose of admitting either a hot roller ol 306 CALENDER. CALICO-PRINTING. 307 iron, or steam when hot calendering is required. The other cylinders used formerly to be made of wood, but it was liable to many defects. The advantage of the paper roller consists in its being devoid of any tendency to split, crack, or warp, especially when exposed to a considerable heat from the contact and pressure of the hot iron rollers. The paper, moreover, takes a vastly finer polish, and, being of an elastic nature, presses into every pore of the cloth, and smooths its surface more effectually than any wooden cylinder, however truly turned, could possibly do. The paper cylinder is constructed as foUows :— The axis of the cylinder is a stron«» square bar of the best wrought iron, cut to the proper length. Upon this bar a strong round plate of cast iron is first put, somewhat less in diameter than the cylinder when finished. A quantity of thick stout pasteboard is then procured, and cut into round pieces an inch larger in diameter than the iron plate. In the centre of the plates, and of every piece of the pasteboard, a square hole must be cut to receive the axis; and, the circle being divided into six equal parts, a hole must also be cut at each of the divisions an inch or two within the rim. These pieces of pasteboard being successively put upon the axis, a long bolt of malleable iron, with a head at one end, and screwed at the other, is also introduced through each of the holes near the rim; and this is continued ttntil a suflicient number of pasteboards are thus placed to form a cylinder of the length required, proper allowance being made for the compression which the pasteboard IS afterwards to undergo. Another round plate is then applied, and, nuts being pat upon the screws, the whole are screwed tight, and a cylinder formed. This cylinder is now to be placed in a stove, exposed to a strong heat, and must be kept there for at least several days ; and, as the pasteboard shrinks by exposure to the heat, the screws must be frequently tightened until the whole mass has been compressed as much as possible When the cylinder is thus brought to a suflicient degree of density, it is removed from the stove ; and, when allowed to cool, the pasteboard forms a substance almost incon- ceivably dense and hard. Nothing now remains but to turn the cylinder ; and this is an operation of no slight labor and patience. The motion in turning must be slow, not exceeding about forty revolutions in a minute ; the substance being now so hard and tough that tools of a very small size must be used to cut, or rather scrape it, until it is true. Three men are generally employed for the turnin?, even when the motion of the cylinder is effected by mechanical power, two being necessarj' to sharpen tools for the third, who turns, as quickly as he blunts them. Let us suppose it to be a five-rollered machine: when a person stands in front of the calender, the cloth coming from behind above the uppermost cylinder 1, passes be- tween 1 and 2 : proceeding behind 2, it again comes to the front between 2 and 3 • between 3 and 4 it is once more carried behind, and, lastly, brought in front between 4 and 5, where it is received, and smoothly folded on a clean board, or in a box by a person placed there for the purpose. In folding the cloth at this time, care roust be taken that it may be loosely done, so that no mark may appear until it be again foWed in the precise length and form into which the piece is to be made up. The foldin*' may be done either by two persons or by one, with the aid of two sharp polished spikes placed at a proper distance, to ascertain the length of the fold, and to make the whole equal. When folded into lengths, it is again folded across upon a smooth clean table according to the shape intended, which varies with the different kinds of goods, or the particular market for which the goods are designed. When the pieces have received the proper fold, the last operation previous to packing them IS the pressing. This is commonly performed by placing a certain number of pieces, divided by thin smooth boards of wood, in a common screw press, similar to those used by printers for taking out the impression left by the types in the printing-press. Be- sides the wooden boards, a piece of glazed pasteboard is placed above and below every piece of cloth, that the outer folds may be as smooth and glossy as possible. The operation of the common screw press being found tedious and laborious, the hydrau- lic press is now m all well-mounted establishments had recourse to. See Hydrauuc Press. No improvements that have taken place in calendering can exceed the power and fa- cility of the water press : one of these presses mt^y be worked by two men, who can with great ease produce a pressure of 400 tons ; but, in considerable establisliments, the presses are worked by power. See Bandanna . The appearance and finish of the goods, in consequence of such an immense wei«»ht acting on them, are materially improved. ° The press is also used for the purpose of packing ; whereby the bale is rendered much more compact than formerly. It is commonly roped, &c., while in this compressed state ; the dimensions are therefore greatly diminished from what they would otherwise be by any other method. For instance, the same quantity of goods packed in a bale are from one third to one half less bulky than if they were packed in a box with tht atmost force of the hands. Tor lawns and muslins of a light texture, the operation of smoothing rpc-.^ires a dil. ferent process in some respects than close heavy fabrics. They only require to be slightly smoothed to remove any marks which they may have received at the bleaching; and as fheir beauty depends rather on their transparency than their closeness, the more the cy lyndrical form of the yarn is preserved the better. They are therefore put through a small machine, consisting of three rollers or cylinders; and as the power required to move this is small, the person who attends it generally drives it by a small winch ; or the same effect may be produced by passing the muslins between only two or three rollers of the above calender, lightly loaded. In the thick fabrics of cloth, including those kinds which are used for many parts ot household furniture, as also those for female dress, the operation of glazing is used both to add to the original beauty of the cloth, and to render it more impervious to dust or smoke. The glazing operation is performed entirely by the friction of any smooth substance upon the cloth ; and, to render the gloss brighter, a small quantity of bleached wax is previously rubbed over the surface. The operation of glazing by the common plan is very laborious, but the apparatus is of the most simple kind. A table is mounted with a thick stout cover of level and well-smoothed wood, forming an inclined plane ; that side where the operator stands at work being the lowest. The table is generally placed near a wall, both for convenience in suspending the glazing apparatus, and for the sake of light. A long piece of wood is suspended in a groove formed between two longitudinal beams, placed parallel to the wall, and fixed to it. The groove resembles exactly the aperture between the shears of a common turning lathe. The lever, of which the groove may be supposed to be the centre or fulcrum, is faced at the bottom with a semi-cylindrical piece of finely polished flint, which gives the friction to the cloth stretched upon the table below. Above the flint are two cross handles, of which the operator lays hold, and moves them backward and forward with his hands, keeping the flint press- ing slightly upon the cloth. When he has glazed a portion equal to the breadth of the flint, he moves his lever between the shears sidewise, and glazes a fresh part : thus he proceeds from one side or selvage of the cloth to the other ; and when all which is upon the table is sufficiently glazed, he draws it over, and exposes a new portion to the same operation. To preseive the cloth at a proper tension, it may be wound smoothly upon a roller or beam, which being set so as to revolve upon its own axis behind the table, another roller to receive the cloth may be placed before, both being secured by a catch, acting in a ratchet wheel. Of late years, however, a great part of the labor employed in glazin? cloth has been saved, as the common four or five bowl calender has been altered to fit this purpose by direct pressure. As a matter of accommodation, the different processes of packing, cording of boxes, sheeting of trunks, and, in general, all the arrangements preparatory to shipments, and also the intimations and surveys necessary for obtaining drawbacks, debentures, or bounties, according to the excise laws, are generally conducted at the calender houses where goods are finished. Tliese operations sufficiently account for the general meaning attached to the word. CALICO-PRINTING (Impression d'Indiennes, Fr. ; Zeugdruckerei, Germ.) is the art of impressing cotton cloth with topical dyes of more or less permanence. Of late years, silk and woollen fabrics have been made the subjects of a similar style of dyeing. Linens were formerly stained with various colored designs, but since the modern improvements in the manufacture of cotton cloth, they are seldom printed, as they are both dearer, and produce less beautiful work, because flax possesses less affinity than cotton for coloring matters. This art is of very ancient date in India, and takes its English name from Calicut, a district where it has been practised with great success from time immemorial. The Egyptians, also, appear from Pliny's testimony to have practised at a remote era some of the most refined processes of topical dyeing. ** Robes and white veils," says he, "arc painted in Egypt in a wonderful way. They are first imbued, not with dyes, but with dye-absorbing drugs, by which, though they seem to be unaltered, yet, when immersed for a little while in a caldron of the boiling dye-liquor, they are found to become painted. Yet, as there is only one color in the caldron, it is marvellous to see many colors imparted to the robe, in consequence of the influence of the excipient drug. Nor can the dye be washed out. A caldron, which would of itself merely confuse the colors of cloths previously dyed, is thus made to impart several pigments from a single dye- stuff, painting as it tot/*." The last expression, ptrtgiYgtte dum coquit, is perfectly graphic and descriptive of calico-printing. The cotton chints counterpanes of great size, called paUampoors, which have been manufactured in Madras from the earliest ages, have in like manner peculiar dye-absorb- ing drugs applied to them with the pencil, as also wax, to protect certain parts of the surface from the action of the dye, and are afterwards immersed in a staining liquor, which, when wax is applied, is usually the cold indigo-vat, but without the wax is a hot liquor similar to the Egyptian. M. Koechlin Roder, of JMulhouse, brought home lately from 308 CALICO-PRINTING. CALICO-PRINTING. 309 India a rich collection of cloths in this state of preparation, which I saw in the ^bmet of the Societe Indusirielk of that interesting emporium of calico-printing. The native implements for applying the wax and coloring bases are placed along- side of the cloths, and form a curious picture of primeval art. There is among other samples an ancient pallampoor, five French yards long, and two and a half broad jaid to be the labor of Hindoo princesses, which must have taken a lifetime to execute* The printing machinery of great Britain has begun to supersede, for these styles o} work, the cheapest hand labor of India. Calico-printing has been for several hundred years practised by the oriental methods in Asia Minor and the Levant; but it was unknown as an English art till 1696 when a small print-ground was formed upon the banks of the Thames, near Richmond' by a Frenchman— probably a refugee from his own countr>', in consequence of the revocation of the edict of Nantes. Some time afterwards, a considerable printine work was estabUshed at Bromley Hall, in Essex, and several others sprung up succe^ sively m Surrey, to supply the London shops with chintses, their import from India having been prohibited by act of parliament in 1700. The silk and woollen weavers indeed, had all along manifested the keenest hostility to the use of printed calicoes' whether brought from the East or made at home. In the year 1680 they mobbed the India House in revenge for some large importations then made of the chintses of Malabar. They next induced the government, by incessant clamors, to exclude alto- gether the beautiful robes of Calicut from the British market. But the printed goods, imported by the English and Dutch Easl India companies, found their way into this country, m spite of the excessive penalties annexed to smuggling, and raised a new alarm among the manufacturing population of Spitalfields. The sapient legislators of that dav intimidated as would appear, by the East London mobs, enacted in 1720 an absurd sumptuary law, prohibiting the wearing of all printed calicoes uhaisoever, either of foreign or domestic ongin. This disgraceful enactment, "worthy of the meridian of Cairo or Algiers, proved not only a death-blow to rising industry in this ingenious department of the arts, but prevented the British ladies from attiring themselves in the becoming drapery of Hmdostan. After an oppressive operation of ten years, this act was repealed ^,* J^""^- • 7 enhghtened set of senators, who were then pleased to permit what they called British calicoes, if made of linen warp, with merely weft cf ihe kaied cotton, to be printed and worn, upon paying a duty of no less than sixpence the square yard. Under this burden, English calico-printing could not be expected to make a rapid progress. Accordingly, even so lately as the year 1750, no more than 50,000 pieces of mixed Stuff were printed m Great Britain, and that chiefly in the neighborhood of London • whereas a single manufacturer, Mr. Coates of Manchester, now-a-days will turn off nearly twenty times that quantity, and there are very many others who manufacture several hundred thousand pieces per annum. It was not till about 1766 that this art migrated into Lamcash ire, where it has since taken such extraordinary development- but It wa5 only after 1774 that it began to be founded upon right principles, in consel quence of the repeal of that part of the act of 1730 which required the warp to be made of linen yarn. Henceforth the printer, though still saddled with a heavy duty of 3d the square yard, was allowed to apply his colors to a homogeneous web, instead of the m'ixed labric of hnen and cotton substances, which differ in their affinities for dyes. France pursued for some time a similar false policy with regard to calico-printino- but she emerged sooner from the mists of manufacturing monoiwly than England. ""Her avowed motive was to cherish the manufacture of flax, a native product, instead of that ^ cotton a raw material, for which prejudice urged that money had to be exported. Her intelligent statesmen of that day, fully seventy years ago, replied that the money expended in the purchase of cotton was the produce of French industry, beneficially employed, and they therefore took immediate measures to put the cotton fabrics upon a footing of equality. MeanwhUe the popular prejudices became irritated to such a degree, by the project of permuting the free manufacture and sale of printed cottons, that ever^ French town possessed of a chamber of commerce made the strongest remonstrances against It. The Rouen deputies declared to the government, « that the intended mea- sure won d throw its inhabitants mto despair, and make a desert of the surrounding country: those of Lyons said, "the news had spread terror through all its workshops :^ Tours "foresaw a commotion likely to convulse the body of the state :" Amiens said, "that the new law would be the grave of the manufacturing industry of France ;» and Paris declared that her merchants came forward to bathe the throne with their tears upon that inauspicious occasion." The government persisted in carrying its truly enlightened principles into effect, and with so manifest advantage to the nation, as to warrant the inspector-general of manu !f5=i"^^« *° make, soon afterwards, the following appeal to those prejudiced bodies :- « WiU any of you now deny that the fabrication of printed cottons has occasioped a vast extension of the industry of France, by giving profitable employment to a great many i hands in spinning, weaving, bleaching, and printing the colors ? Look only at the dyeing department, and say whether it has not done more good to France in a few years than many of your other manufactures have in a century ?" The despair of Rouen has been replaced by the most signal prosperity in the cotton trade, and especially in printed calicoes, for the manufacture of which it possesses 70 different establishments, producing upwards of a million of pieces of greater average size and price than the English. In the district of the Lower Seine, round that town, there are 500 cotton factories of different kinds, which give employment to 118,000 operatives of all orders, and thus procure a comfortable livelihood to probably not less than half a million of people. The repeal, in 1831, of the consolidated duty of S^d. per square yard upon printed calicoes in Great Britain is one of the most judicious acts of modern legislation. By the improvements in calico-printing, due to the modern discoveries and inventions in chem-rtry and mechanics, the trade had become so vast as to yield in 1830 a revenue of 2,280,000/. levied upon 8,596,000 pieces, of which, however, about .hree fourths were exported, with a drawback of 1,579,000/. 2,281,512 pieces were consumed in that year at home. When the expenses of collection were deducted, only 350,000/. found their way into the exchequer, for which pitiful sum thousands of frauds and obstructions were committed against the honest manufacturer. This reduction of duty enables the con- sumer to get this extensive article of clothing from 50 to 80 per cent, cheaper than before, and thus places a becoming dress within the reach of thousands of handsome females in the humbler ranks of life. Printed goods, which in 1795 were sold for two shillings and three-pence the yard, may be bought at present for eight-pence. In fact, a woman may now purchase the materials of a pretty gown for two shillings. The repeal of the tax has been no less beneficial to the fair dealers, by putting an end to the contra- band trade, formerly pursued to an extent equally injurious to them and the revenue. It has, moreover, emancipated a manufacture, eminently dependant upon taste, science, and dexterity, from the venal curiosity of petty excisemen, by whom private improve- ments, of great value to the inventor, were in perpetual jeopardy of being pirated and sold to any sordid rival. The manufacturer has now become a free agent, a master of his time, his workmen, and his apparatus ; and can print at whatever hour he may re- ceive an order ; whereas he was formerly obliged to wait the convenience of the excise oflicer, whose province it was to measure and stamp the cloth before it could be packed, -—an operation fraught with no little annoyance and delay. Under the patronage of par- liament, it was easy for needy adventurers to buy printed calicoes, because they could raise such a sum by drawbacks upon the export of one lot as would go far to pay for another, and thus carry on a fraudulent system of credit, which sooner or later merged in a disastrous bankruptcy. Meanwhile the goods thus obtained were pushed ofi' to some foreign markets, for which they were possibly not suited, or where they produced, by their forced sales, a depreciation of all similar merchandise, ruinous to the man who meant to pay for his wares. The principles of calico-printing have been very profoundly studied by many of the French manufacturers, who generally keep a chemist, who has been educated in the Parisian schools of science, constantly at work, making experiments upon colors in a well-mounted laboratory. In that belonging to M. Daniel Koechlin, of Mulhausen, there are upwards of 3000 labelled vials, filled with chemical reagents, and specimens subservient to dyeing. The great disadvantage under which the French printers labor is the higher price they pay for cotton fabrics above that paid by the English printers. It is this circumstance alone which prevents them from becoming very formidable rivals to us in the markets of the world. M. Barbet, deputy and mayor of Rouen, in his replies to the ministerial commission of inquiry, rates the disadvantage proceeding from that cause at 2 francs per piece, or about 5 per cent, in value. In the annual report of the Societe IndustrieVe of Mulhausen, made in December, 1833, the number of pieces printed that year in Alsace is rated at 720,000, to which if we add 1,000,000 for the produce of the department of the Lower Seine, and 280,000 for that of St. Quentin, Lille, and the rest of France, we shall have for the total amount of this manufacture 2,000,000 of pieces, equivalent to nearly 2,400,000 pieces English ; for the French piece usually measures 33J aunes, = 41 yards nearly ; and it is also considerably broader than the English pieces upon an average. It is therefore probable that the home consumption of France in printed goods is equal in quantity, and superior in value, to that of England. With regard tc the comparative skill of the workmen in the two countries, M. Nicholas Koechlin, deputy of the Upper Rhine, says, that one of his foremen, who worked for a year in a print- field in Lancashire, found little or no difference between them in that respect. The English wages are considerably higher than the French. The machines for multiplying production, which for some time gave us a decided advantage, are now getting into very general ^se among our neighbors. In my recent visit to Mulhausen, Rouen, and theif environs, I had an opportunity of seeing many printing establishments mounted with all the resources of the most refined mechanisms. 310 CALICO-PRmTING. « J**^ caJico-printing of this country stiU labors under the burden of considerable taxes upon madder and gallipoli oil, which have counteracted the prosperity of our Turkey red styles of work, and caused them to flourish at Elberfeldt, and some other places on the conunent whither a good deal of the English yarns are sent to be dyed, then brou«'ht back, and manufactured into ginghams, checks, &c., or foi-warded directly .thence to our Kussian customers. This fact places our fiscal laws in the same odious light as the fa- cility of pirating printers* patterns with impunity does our chancery laws. Before cloth can receive good figured impressions its surface must be freed from fibrous c reDrc! Thit r^oll '•'^™^'.'' '""r^ "^^''^y P^""°^^ ^"^° '^^ thickened colo/o? the trou'h bT That roller is also made to bear, with a moderate force, against a, and thus recefves b^ fromT' '" VT "^'f' ^ movement of rotation. But it'is'preferable to dri^ve the rolL c from the cyhnder a, by means of a system of toothed wheels attached to their ends so that the surface speed of the wooden or paste roller shall be somewhat greater than that of pa^f of th^'latr.'"' "'"''' ''^ ^°^°' "'" ^ "^''^''' ^ '' ^^^^ into'the^^n^r^lel As the cylinder a is pressed upwards against b, it is obvious that the bearpr^ nf i>.« trough and its roller must be attached "o the bearings of the cvl nder a^LI ^ preserve its contact with the color-roller c. 6 is a sh^ ed^d V f^^^^^^^^ Jj steel caliedtheco/orrfoc/or, screwed between two gun-metal stiffen ngWs" tTeed^e of which wiper is shghtly pressed as a tangent upon the engraved roller A This rnW vibrates with a slow motion from side to side, or right to left,%o as to exercise a delicitl shaving action upon the engraved surface, as this revolves ri the directfonTthe a ro^^^ fir^^'\'-T^" sharp-edged ruler, called the lint doctor, whose offiie it s to remove any fibres which may have come off the calico in the act of printing and which inJft on the enffrared cyhnder, would be apt to occupy some of the lines or nt l.,T. ! ' . the color from filling them all. This'««. doJJis p'esstd v:^ s^^^^^^^^ A, and has no transverse motion. ^ cjunaer What was stated with regard to the bearers of the color trough d, namelv that ih^^ are connected and moved up and down together with the bearings of heTylinder a maJ also be said of the bearers of the two doctors. ^ji'uuer a, may The working of this beautiful mechanism may now be ea^silv comnrehpni^P^ Ti.- l"l"i tn^'^'^i^^i-d '^^ the figure by the letter d, is iLX'^d o^'carri^^^^^^^^^ aW with the blanket stuff a a, in the direction of the a;row, and is moved onward bv tS! '^rV::ro:\tV^^-' ^>'^^"^-^'- - - -"^- ^^^ in.pressiono1tr;^?eJj;?n! ^ifihTAZ'tT^ '"^ 1'''"^' ^^' ^""'^ '^"^P^^^ calico-machine which prints upon ^bonous and expensive operation. The happy invention ^maTb^MrftLperS in Amenca, for transferring ensrav nss from one surface in .„«iLt i.,, / ! roUer dies, was with great judgment applied by Mr locket in^^" ^ ■ ,• ' "^ ?'"' .go as the year ,808! before fhe flrst'^?nven./r clm^to'Eu :p:trr;fan ° fe pattern is iirst drawn upon a scale of about 3 inches wuare T.i>., Vi,:; .-, c'. "* being repeated a definite number of times, will ioveMhe cv^tnde/ Thf, .. f • *'"" engraved in intaglio upon a roller of soflened steel, atout I «h in'diameter"nd 3 ?„°k" loi.g,«> that ,t wiU exactly occupy its surf«e.' The engraver SI'S eje;"* 11 lens when employed at this delicate work. This roller is hardened by heating it to a cherry-red in an iron case containing pounded bone-a^, and then plunging it into cold water ; its surface being protected from oxydizement by a chalky paste. This hardened roller is put into a press of a peculiar construction, where, by a rotatory pressure, it trans fers its design to a similar roller in the soft state ; and as the former was in intaglio, thi latter must be in relievo. This second roller being hardened, and placed in an appro priate volutory press, is employed to engrave by indentation upon the full-sized coppei cylinder the whole of its intended pattern. The first roller engraved by hand is called the die; the second, obtained from it by a process like that of a milling tool, is called lh# mill. By this indentation and multiplication system, an engraved cylinder may be had foi seven pounds, which engraved by hand would cost fifty or upwards. The restoration of a worn-out cylinder becomes extremely easy in this way ; the mill being preserved, need merely be properly rolled over the copper surface again. At other times, the hard roller die is placed in the upper bed of a screw press, not un- like that for coining, while the horizontal bed below is made to move upon strong rollers mounted in a rectangular iron frame. In the middle of that bed a smooth cake or flat disc of very soft iron, about 1 inch thick, and 3 or 4 inches in diameter, is made fast by four horizontal adjusting screws, that work in studs of the bed frame. The die being now brought down by a powerful screw, worked by toothed wheel-work, and made tc press with force upon the iron cake, the bed is moved backwards and forwards, causing the roller to revolve on its axles by friction, and to impart its design to the cake. This iron disc is now case-hardened by being ignited amidst horn shavings in a box, and then suddenly quenched in water, when it becomes itself a die in relievo. This disc die is fixed in the upper part of a screw press with its engraved face downwards, yet so as to be moveable horizontally by traverse screws. Beneath this inverted bed, sustained at its upper surface by friction-rollers, a copper cylinder 30 inches long, or thereby, is mounted horizontally upon a strong iron mandrel, furnished with toothed wheels at one of its ends, to communicate to it a movement upon its axis through any aliquot arcs of the circle. The disc die being now brought down to bear upon the copper cylinder, this is turned round through an arc corresponding in length to the length of the die ; and thus, by the steady downward pressure of the screw, combined with the revolution of the cy- linder, the transfer of the engraving is made in intaglio. This is, I believe, the most con- venient process for engraving, by transfer, the copper of a one-cylinder machine. But when 2, 3, or 4 cylinders are to be engraved with the same pattern for a two, three, or four-colored machine, the die and the mill roller plan of transfer is adopted. Tn this case, the hardened roller die is mounted in the upper bed of the transfer press, in such a way as to be capable of rotation round its axis, and a similar roller of softened steel IS similarly placed in the under bed. The rollers are now made to bear on each other by the action of the upper screw, and while in hard contact, the lower one is caused to re- volve, which, carrying round the upper by friction, receives from it the figured impression in relief. When cylinders for a three-colored machine are wanted, three such mills are made fac-similes of each other; and the prominent parts of the figure which belong to the other two copper cylinders are filed off in each one respectively. Thus three differ- ently figured mills are very readily formed, each adapted to engrave its particular figure upon a distinct copper cylinder. Some copper cylinders for peculiar styles are not graved by indentation, as just de- scribed, but etched by a diamond point, which is moved by mechanism in the most curious variety of configurations, while the cylinder slowly revolves in a horizontal line beneath it. The result is extremely beautiful, but it would require a very elaborate set of drawings to represent the machinery by which Mr. Locket produces it. The copper is covered by a re- sist varnish while being heated by the transmission of steam through its axis. After being etched, it is suspended horizontally by the ends, for about five minutes, in an oblong trough charged with dilute nitric acid. With regard to the two and three-colored machines, we must observe, that as the calico in passing between the cylinders is stretched laterally from the central line of the web, the figures engraved upon the cylinders must be proportionally shortened, in their lateral di- mensions especially, for the first and second cylinder. Cylinder printing, though a Scotch invention, has received its wonderful develop- ment in England, and does the greatest honor to this country. The economy of labor introduced by these machines is truly marvellous ; one of them, under the guidance of a man to regulate the rollers, and the service of a boy, to supply the color troughs, being capable of printing as many pieces as nearly 200 men and boys could do with blocks. The perfection of the engraving is most honorable to our artisans. The French, with all their ingenuity and neat-handedness, can produce nothing approaching in excellence to the engraved cylinders of Manchester, — a painful admission, universally made to me by every eminent manufacturer in Alsace, whom I visited in my late tour. t» I l< 314 CALICO-PRINTING Another modification of cylinder printing, is that with wooden rollers cut in relief; it 18 called surface printing, probably because the thickened color is applied to a tense sar face of woollen cloth, from which the roller takes it up by revolving in contact with the cloth. When the copper cylinders and the wooden ones are combined in one ajiu)arata8« it has got the appropriate name of the union printing machine. In mounting three or more cylinders in one frame, many more adjustments become ne- cessary than those described above. The first and most important is that which ensures the correspondence between the part3of the figures in the successive printing rollers, fof unless those of the second and subsequent engraved cylinders be accurately inserted into their respective places, a confused pattern would be produced upon the cloth as it advan- ces round the pressure cylinder b, figs. 233, 234. Each cylinder must have a forward adjustment in the direction of rotation round its axis, so as to bring the patterns into correspondence with each other in the length of the piece; and also a lateral or traverse adjustment in the line of its axis, to efllect the corres- pondence of the figures across the piece ; and thus, by both together, each cylinder may be made to work symmetrically with its fellows. Fig. 297 is a cross section of a four-color cylinder machine, by which the working parts are clearly illustrated. A A A is a part of the two strong iron frames or cheeks, in which the various rollers are mounted. They are bound together by the rods and bolts a a a a. B is the large iron pressure cylinder, which rests with its gudgeons in bearings or bnsh- es, which can be shifted up and down in slots of the side cheeks a a. These bus'ues are suspended from powerful screws 6, which turn in brass nuts, made fast to the top of the frame a, as is plainly shown in the figure. These screws serve to counteract the strong pressure applied beneath that cylinder, by the engraved cylinders d e. c D E F are the four printing cylinders, named in the order of their operation. Thfy consist of strong tubes of copper or gun-metal, forcibly thrust by a screw press upon the iron mandrels, round which as shafts they revolve. The first and last cylinder c and f are mounted in brass bearings, which may be shifled in horizontal slots of the frame a. The pressure roller b, against whose surface they bear with a very little obliquity downwards, may be nicely adjusted to that pressure by its elevating and depressing screws. By this means c and r can be adjusted to b with geo- metrical precision, and made to press it in truly opposite directions. The bearings of the cylinders d and e are lodged also in slots of the frame a, which point obliquely upwards, towards the centre of b. The pressure of these two print cylin- ders c and F is produced by two screws c and rf, which work in brass nuts, made fast to the frame and very visible in the figure. The frame-work in which these bearings and screws are placed, has a curvilinear form, in order to permit the cylinders to be readily removed and replaced; and also to introduce a certain degree of elasticity. Hence the pressure applied to the cylinders c and f, partakes of the nature of a spring ; a circum- stance essential to their working smoothly, on account of the occasional inequalities in the thickness of the felt web and the calico. The pressure upon ir.e other two print cylinders d and e is produced by weights acting with levers against the bearings. The bearings of d are, at each of their ends, acted upon by cylindrical rods, which slide in long tubular bosses of the frame, and press with their nuts g at their under end upon the small arms of two strong levers g, which lie on each side of the machine, and whose fulcrum is at h (in the lower corner at the left hand). The long arms of these levers g, are loaded with weights h, whereby they are made to press up against the bearings of the roller p, with any degree of force, by screwing up the nut g, and hanging on the requisite weights. The manner in which the cylinder e is pressed up against b, is by a similar construc- tion to that just described. With each of its bearings, there is connected by the link Jfc, a curved lever i, whose fulcrum or centre of motion is at the bolt /. To the outer end of this lever, a screw, w, is attached, which presses downwards upon the link n, connect- ed with the small arm of the strong lever fe, whose centre of motion is at o. By turning therefore the screw m, the weight l, laid upon the end of the long arm of the lever k (o1f which there is one upon each side of the machine), may be made to act or not at pleasure upon the bearings of the cylinder e. In tracing the operation of this exquisite printing machine, we shall begin with the first engraved cylinder c. Its bearings or bushes shift, as was already stated, in slots of the frame A. Each of them consists of a round piece of iron, to which the end of the screw c is joined, in the same way as at d, in the opposite side. In each of these iron bearings, a concave brass is inserted to support the collar of the shaft, and in a dove- tailed slit of this brass, a slidins: piece is fitted, upon which a set or adjusting screw in the iron bearing acts, and which, being forced against the copper cylinder c, serves to adjust the line of its axis, and to keep it steady between its bearings, and true in its rotatory motion. Upon the iron bearing a plate is screwed, provided with two flanges^ 15 CALICO-PRINTING. 315 which support the color trough 9, and the color roller m. This trough, as well as the others to be mentioned presently, is made of sheet copper in the sides and bottom, and 297 fixed upon a board ; but its ends are made of plates of cast copper or gun-metal to serve as bearings to the color roller m. The trough and its roller may be shifted both together into contact with the printing cylinder c, by means of the screw r. Near s, seen above the roller, c, and t below it, are sections of the two doctors, which keep the engraved cylinders in sound working condition ; the former being the colour doctor, and the latter tte lint doctor. Their ends lie in brasses, which may be adjusted by the screws u and v, working in the respective brackets, which carry their brasses, and are made fast to the iron bearings of the cylinder. The pressure of the color doctor is produced by two weights tr, (see high up on the frame work,) which act on a pair of small levers x, (one on each side of the machine,) and thus, by means of the chains, tend to lift the arms y, attached to the end axles of the doctor. The pressure of the lint doctor upon the cylinder c, is performed by the screw t, pressing upon an arm which projects downwards, and is attached to the axle of that doctor. The bearings of the second printing cylinder d, consist at each end of a mass of iron (removed in the drawing to show the mechanism below it), which shifts in the slanting slot of the frame a. In each of these masses there is another piece of iron, which slides in the transverse direction, and may be shifted by the adjusting screw a' fixed to it, and working in a nut cast upon the principal bearing above described. To the inner bear ings, which carry the brasses in which the shaft lies, are screwed the two curved ann* 6' h' to which are attached the bearings &c., for the color trough and the doctors. In these brasses there are also dovetailed pieces, which slide and are pressed by set screws furnished with square heads in the iron secondary bearings, which sei ve, as before said, to adjust the printing cylinder in the line of its axis, while other screws adjust the distance of the cloth upon which the second color is printed, and the line of contact with the cylinder b. N, is the color roller of d, and d' the color trough, which rests by its board upon the lever e"; whose centres of motion /'« are made fast to the curved arms 6', fixed at the 316 CALICO-PRINTING. CALICO-PRINTING S17 bearings of the cylinder, and whose ends are suspended by screws g' ; whereby the color roller n, may be pressed with greater or less force to the cylinder d. h' and t' are the two doctors of this cylinder ; the former being the color, the latter the lint doctor. They rest, as was said of the cylinder c, in brasses which are adjustable by means of screws, that work in the studs or brackets by which the brasses are supported. These brackets must of course be screwed to the secondary bearing-pieces, in order that they may keep their position, into whatever direction the bearings may be shifted, k' and /' are these set screws for the color and lint doctors. The pressure of the former upon the cylinder d, is produced by weights m', acting upon levers »', and pressing by rods or links o', upon arms attached to each end of the axis of the docliw. (See the left hand side of the figure near the bottom.) The lint-doctor i' is pressed in a similar way at the other side upon the cylinder d, by the weights acting upon levers p', and by rods q' upon arms fixed at each end of the axis of the doctor. The bearings of the third printing cylinder e, are of exactly the same construction as that above described, and therefore require no particular detail. The lint doctor *, is here pressed upon the engraved cylinder by screws /', working in the ends of studs or arms fixed upon each end of the axis of the doctor, and pressing upon flanges cast upon the brackets in which the brasses of the doctor's axis lie, which are made fast to the bear- ings of the cylinder e. The bearings of the fourth copper cylinder f, are also constructed in a similar way. Each consists of a first bearing, to which is joined the end of the screw d, by which it is made to slide in a slot of the frame. Another bearing, which contains the brass for the shaft of the cylinder, can be shifted up and down in a transverse direction by a screw ar', of the second bearing, working in a nut cast upon the first bearing. To this secondary bearing, plates are made fast by the screws v' v' to the inside, to carry the studs or brackets of the doctors x' and y'. In the brasses of the cylinder shaft, dovetailed pieces are made to slide, being pressed by set screws w', against the engraved cylinder f, similar to what has been described for adjusting the cylinders to one another. This cylinder has no separate color roller, nor trough, properly speaking, but the color doctor y' is made concave to serve the purpose of a trough in supplying the engraved lines of the cylinder with color. With this view the top plate of the doctor is curved to contain the colored paste, and it is shut up at the ends by pieces of wood made to fit the curvature of the doctor. Its pressure against the engraved surface is produced by weights a", acting at the ends of arms 6", attached to the ends of the axis of the doctor. The pressure of the lint doctor x' is given by screws c", working in arms attached to the ends of the axis of the doctor, and pressing upon the flanges d", cast upon the brackets which carry the brasses for the axis of the doctor. These brasses are themselves adjustable, like those of all the other cylinders, by set screws in the brackets, which work in the nuts formed in the brasses. e" e", is the endless web of felt stuff which goes round the cylinder b, and constitutes the soft elastic surface upon which the printing cylinders c, d, e, and f exercise their pressure. This endless felt is passed over a set of rollers at a certain distance from the machine, to give opportunity for the drying up of any coloring paste which it may have imbibed from the calico in the course of the impressions. In its return to the ma- chine in the direction of the arrow, it is led over a guide roller o, which is thereby made to revolve. Upon the two ends of this, and outside of the bearings which are fixed upon the tops of the frame a, are two eccentrics, one of which serves to give a vibratory tra- verse movement to the color doctors «', h', and r' of the three cylinders, c, d, and £, whilst the other causes the color doctor y' of the cylinder f, to make lateral vibra- tions. Q is one of a pair of cast-iron brackets, screwed on at the back of the side-frames or cheeks a a, to carry the roller fiUed with white calico r, ready for the printing operations. Upon the end of the shaft whereon the calico is coiled, a pulley is fixed, over which a rope passes suspending a weight in order to produce friction, and thereby resistance to the action which tends to unwind the calico. In winding it upon that and similar rollers, the calico is smoothed and expanded in breadth by being passed over one or more grooved rods, or over a wooden bar s,}lg. 298, the surface of which is covered with wire, so as to have the appearance of a united right and left-handed screw. By this device, the calico, folded or creased at any part, is stretched laterally from the 298 S centre, and made level. It then passes over the guide-roller o, where it comes upon the surface of the felt c" e", and thence proceeds under its guid- ance to the series of printing cylinders. Three and four-color machines, similar to the above, are now at work in many es- tablishments in Lancashire, which will turn off a piece of 28 yards per minute, each of the three or four cylinders applying its peculiar part of the pattern to the cloth as it passes along, by ceaseless rotation of the unwearied wheels. At this rate, the astonishing length of one mile of many-colored web is printed witn elegant flowers and other figures in an hour. When we call to mind how much knowledge and skill are involved In this process, we may fairly consider it as the greatest achievement of chemical and mechanical science. Before entering upon the different styles of work which constitute calico-printing, 1 shall treat, in the first place, of what is common to them all, namely, the thickening ol the mordants and colors. This is an operation of the greatest importance towards the successful practice of the art. Several circumstances may require the consistence of the thickening to be varied ; such as the nature of the mordant, its density, and its acidity. A strong acid mordant cannot be easUy thickened with starch ; but it may be by roasted starch, vulgarly called British gum, and by gum arabic or Senegal. Some mordants which seem sufficiently inspissated with starch, liquefy in the course of a few days, and, being apt to run in the priniing-on, make blotted work. In France, this evil is readily obviated by adding one ounce of spirits .of wine to half a gallon of color — a remedy which the English excise duties render too costly. The very same mordant, when inspissated to difierent degrees, produces diflferent tints in the dye-copper — a diflerence due to the increased bulk from the thickening substance ; thus, the same mordant, thickened with starch, furnishes a darker shade than when thickened with gum. Yet there are circumstances in which the latter is preferred, be- cause it communicates more transparency to the dyes, and because, in spite of the wash- ing, more or less of the starch always sticks to the mordant. The gum has the inconvenience, however, of drying too speedily, and of also increasing too much the volume of the mordants ; by both of which causes it obstructs their combination with the stuflf, and the tints become thin or scratchy. The substances generally employed as thickeners are the following : — 1. Wheat starch. 2. Flour. 3. Roasted starch. 4. Gum Senegal. 5. Gum tragacanth. 6. Salep. 7. Pipe-clay, mixed with gum Senegal. 8. Sulphate of lead. 9. Sugar. 10. Molasses. 11. Glue. After thickening with gum, we ought to avoid adding metallic solutions in the liquid state ; such as nitrate of iron, of copper, solutions of tin, of subacetate of lead, &c. ; •8 they possess the property of coagulating gum. I shall take care to specify the nature mnd proportion of thickening to be employed for each color ; a most important matter, hitherto neglected by English writers upon calico-printing. The atmosphere of the printing shops should never be allowed to cool under 65® or 70° F. ; and it should be heated by proper stoves in cold weather, but not rendered too dry. The temperature and moisture should therefore both be regulated with the aid oi thermometers and hydrometers, as they exercise a great influence upon all the printing processes, and especially upon the combination of the mordant with the cloth. In the course of the desiccation, a portion of the acetic acid evaporates with the water, and sub- acetates are formed, which combine with the stuff in proportion as the solvent principle escapes ; the water, as it evaporates, carries off acetic acid with it, and thereby aids the fixation of bases. These remarks are peculiarly appropriate to delicate impressions by the cylinder machine, where the printing and drying are both rapidly effected. In the lapis lazuli style, the strong mordants are apt to produce patches, being thickened with pipe-clay and gum, which obstruct the evaporation of the acids. They are therefore apt to remain, and to dissolve a portion of the mordants at their immersion in the blue vat, or at any rate in the dnng bath. In such a case, a hot and humid air is indispensable, after the application of the mordants, and sometimes the stuffs so impregnated must be suspended in a damp chamber. To prevent the resist pastes becoming rapidly crusty, substances apparently useless are mixed with them, but which act beneficially by their hygrometric qualities, in retarding the desiccation. Oil also is sometimes added with that view. It is often observed that goods printed upon the same day, and with the same mordant, exhibit inequalities in their tints. Sometimes the color is strong and decided in one part of the piece, while it is dull and meager in another. The latter has been printed m too dry an atmosphere. In such circumstances a neutral mordant answers best, et>pe> eiaUy if the goods be dried in a hot flue, through which humid vapors are in constant circulation. In padding, where the whole surface of the calico is imbued with mordant, the drying 318 CALICO-PRINTING. CALICO-PRINTING. 319 apartmeiit ii flue, in which a great many pieces are exposed at once, shoulil be so con- stnicted as to afford a ready outlet to the aqueous and acid exhalations. The cloth oa^ht to be introduced into it in a distended state; becamse the acetic acid ma/ accumulate in the foldings, and dissolve out the earthy or metallic base of the mordant, causing white and gray spots in such parts of the printed goods. Fans may be employed with great ad- vantage, combined with Hot Flues. (See this article.) In the color laboratory, all the decoctions requisite for the print work should be ready prepared. They are best made by a steam heat, by means of copper boilers of a cylin^ dric form, rounded at the bottom, and incased within a cast-iron cylinder, the steam being supplied to the space between the two vessels, and the dye-stuff and water being intro- duced into the interior one, which for some delicate purposes may be made of tin,*or cop- per tinned inside. A range of such steam apparatus should be placed either along one of the side walls, or in the middle line of the laboratory. Proper tables, diawers, vials, with chemical reagents, measures, balances, &c., should also be provided. The most use- ful dye-extracts are the following : — Decoction of logwood, of Brazil-wood, of Persian berries, of quercitron bark, of nuU galls, of old fustic, of archil or cutbear, of cochineal, of cochineal with ammonia, of catechu. The following mordants should also be kept ready prepared : — 1. Aluminous mordant. Take 50 gallons of boiling water. 100 lbs. of alum. 10 lbs. of soda crystals. 75 lbs. of acetate of lead. The soda should be added slowly to the solution of the alum in the water, and when the effervescence is finished, the pulverized acetate of lead is put in and well stirred about till it be all dissolved and decomposed. During the cooling, the mixture should be raked up a few times, and then allowed to settle. The supernatant liquor is the mordant ; it has a density of IP or 11^° Baume. It serves for reds and pinks, and enters into the com- position of puce and lilach. 2. Aluminous mordant. Take 50 gallons of water. 100 lbs. of alum. 10 lbs. of soda crystals. 100 lbs. of acetate of lead ; — operate as above directed. The supernatant liquor here has a density of 12° Baume ; it is employed for lapis resists or reserves, and the cylinder printing of madder reds. 3. Aluminous mordant. Take 50 gallons of water. 100 lbs of alum. 6 lbs. of soda crystals. 50 lbs. of acetate of lead ; — operate as above directed. This mordant is employed for uniform yellow grounds. 4. Aluminous mordant. This is made by adding potash to a solution of alum, till its earth begins to be separa- ced, then boiling the mixture to precipitate the subsulphate of alumina, which is to be strained upon a filter, and dissolved in acetic acid of moderate strength with the aid of beat. This mordant is very rich in alumina, and marks 20° B. 5. Aluminous mordant. Take 12^ gallons of water. 100 lbs. of alum. 150 lbs. of lifiuid pyrolignite of lime at 11|° Baume. This mordant is made with heat like the first; after cooling, some alum crystallizes, and It marks only 12^° B. ' A mordant is made by solution of alum in potash, commonly called — 6. Aluminate of potash. The caustic ley is prepared by boiling together for an hour 100 ga^ns of water, 200 lbs. of potash, and 80 lbs. of quicklime; the mixture is then allowed to settle, the supernatant liquor is decanted, and evaporated till its density be 35" B. In 30 gallons of that ley at a boiling heat, 100 lbs. of ground alum are to be dissolved. On cooling, crystals of sulphate of potash separate. The clear liquor is to be decanted off. and the crystals being washed with a little water, this is to be added to the ley. About 33 gallons of mordant should be obtained. Mordant for Bluck, The pyrolignite of iron, called iron liquor in this country, is the only mordant used in calico-printing for black, violet, puce, and brown colors. The acetate of alumina, pre- pared from pyroligneous acid, is much used by the calico-printers under the name of red ot yellow liquor, being employed for these dyes. I We may observe that a strong mordant, like No. 2, does not keep so well as one ol mean density, such as No. 1. Too much mordant relatively to the demands of the works should therefore not be made at a time. There are eight different styles of calico-printing, each requiring different methods of manipulation, and peculiar processes. 1. The madder style, to which the best chintses belon?, in which the mordants are api. plied to the white cloth with many precautions, and the colors are afterwards brought up in the dye-bath. These constitute permanent prints. 2. The padding or plaquage style, in which the whole surface of the calico is imbued with a mordant, upon which afterwards different colored fisures may be raised, by the topical application of other mordants joined to the actir -n of the dye-bath. 3. The reserve style, where the white cloth is impressed with figures in resist paste, and is afterward subjected first to a cold dye, as the indigo vat, and then to a hot dye- bath, with the effect of producing white or colored spots upon a blue ground. 4. The discharge or rongeant style, in which thickened acidulous matter, either pure of mixed with mordants, is imprinted in certain points upon the cloth, which is afterwaids padded with a dark-colored mordant, and then dyed, with the effect of showing bright figures on a darkish ground. » 5. China blues; a style resembling blue stone-ware, which requires very peculiar treatment. 6. The decoloring or enlevage style; by the topical application of chlorine or chromic acid to dyed goods. This is sometimes called a discharge. 7. Steam colors ; a style in which a mixture of dye extracts and mordants is topical- ly applied to calico, while the chemical reaction which fixes the colors to the fibre is pro- duced by steam. 8. Spirit colors ; produced by a mixture of dye extracts, and solution of tin, vulgarly called spirit by dyers. These colors are brilliant but fugitive. I. The madder style; called by some dip colors. The true chints patterns belong to it; they have from 5 to 7 colors, several of which are grounded-in after the first dye has been given in the madder bath. In dyeing with madder, sumach, fustic, or quercitron, is sometimes added to the bath, in order to produce a variety of tints with the various mordants at one operation. 1. Suppose we wish to produce flowers or figures of any kind containing red, purpl^ and black colors, we may apply the three mordants at once, by the three-color cylinder machine, putting into the first trough acetate of alumina thickened ; into the second, ace- tate of iron ; and into the third, a mixture of the two ; then drying in the air for a few days to fix the iron, dunging and dyeing up in a bath of madder and sumach. If we wish to procure the finest madder reds and pinks, besides the purple and black, we must apply at first only the acetate of alumina of two densities, by two cylinders, dry, dun?, and dye up, in a madder bath. The mordants of iron liquor for the black, and of iron liquor mixed with the aluminous for purple, must be now grounded-in by blocks, taking care to insert these mordants into their precise spots : the goods being then dried with airing for several days, and next dunged, are dyed up in a bath of madder and sumach. They must be afler^vards cleared by branning. See Bran, Dunging, and Madder. 2. Suppose we wish to produce yellow with red, pink, purple, and black ; in this case the second dye-bath should contain quercitron or fustic, and the spots intended to be yel- low should receive the acetate of alumina mordant. 3. The mordant for a full red may be acetate of alumina, of spec. grav. 1*055, thickened with starch, and tinged with Brazil-wood ; that for a pale red or pink, the same at spec, gravity 1-014, thickened with gum; that for a middling red, the same at spec, gravity 1-027, thickened with British gum ; and for distinction's sake, it may be tinged yellow With Persian berries. The mordant for black is a pyroligneous acetate of iron, of specific gravity 1-04; for purple the same, diluted with six times its volume of water; for chocolate, that iron liquor mixed with acetate of alumina, in various proportions accord- ing to the shade wanted. Sumach is mixed with the madder for all these colors except for the purple. The quantity of madder required varies according to the body of color to be put upon the cloth, being from one pound per piece to three or even four. The ffoods must be entered when the copper is cool, be gradually heated during two or three hours, up to ebullition, and sometimes boiled for a quarter of an hour; the pieces being all the wmie turned with a wince from the one side of the copper to the other. (See Wince.) iney are then washed and boiled in bran and water for ten or fifteen minutes. Whea inere is much white ground in the chints, they must be branned a second or even a thii-^ thpv' ^ alternate washing in the dash-wheel. To complete the purification of the while, iinnH %^/'?. "P*'" ^^^ ^'■ass for a few days ; or what is more expeditious, and equally gooQ u delicately managed, they are winced for a few minutes in a weak solution of cnioride of lime. 4. Ill the gronnding-in for yellow, after madder reds, the aluminous mordant being I 320 CALICO-PRINTING. applied, &c., the piece is dyed, for about an hour, with one pound of quercitron bark, the infusion being gradually heated to 150° or 160°, but not higher. 5. A yellow is sometimes applied in chints work after the other colors are dyed, bj means of a decoction of Persian berries mixed with the aluminous mordant, thickened with flour or gum, and printed-on with the block; the piece, when dry, is passed through a weak carbonated alkaline water, or lime water, then washed and dried for the market. 6. Black mordant. — Take half a gallon of acetate of iron, of spec. grav. 1*04,4 ounces of starch, and 4 ounces of flour. The starch must first be moistened with the acetate, then the flour must be added, the rest of the acetate well mixed with both, and the whole made to boil over a brisk fire for five minutes, stirring meanwhile to prevent adhe- sion to the bottom of the pot. The color must be poured into an earthen pipkin, and well mixed with half an ounce of gallipoli oil. In general, all the mordants, thickened with starch and flour, must be boiled for a few minutes. With British gum or common gum, they must be heated to 160° F., or thereby, for the purpose merely of dissolving them. The latter should be passed through a sieve to separate the impurities often present in common gum. 7. Puce mordant. — Take a quart of acetate of alumina and acetate of iron, each of spec. grav. 1-04, mixed and thickened like the blac*lf. No. 6. To give the puce a reddish tinge, the acetate of alumina should have a specific gravity of 1'048, and the iron liquor only 1-007. Red mordants are thickened with British gum, and are sufl5ciently colored with the addition of any tinging decoction. 8. Violet mordants. — These consist either of a very weak solution of acetate of iron, of specific gravity 1*007, for example ; or of a little of the stronger acetate of 1*04, mixed with acetate of alumina, and a little acetate of copper, thickened with starch or British gum. The shades may be indefinitely varied by varying the proportions of the acetates. When black is one of the colors wanted, its mordant is very commonly printed-on first, and the goods are then hung upon poles in the drj ing-room, where they are aired for a few days, in order to fix the iron by its peroxydizement ; the mordants for red, violet, &,c., are then grounded in, and the pieces are dyed up, after dunging and washing, in the madder bath, into which, for certain shades, sumach, galls, or fustic is added. The goods are brightened with a boil in soap water; occasionally also in a bath, containing a small quantity of solution of tin or common salt. The following mode of brightening is much extolled by the French, who are famous for their reds and roses. 1. A soap boil of forty minutes, at the rate of 1 pound for every 2 pieces. Rinse in clear water. 2. Pass through chloride of soda solution of such strength that two parts of it decolor one part of Gay Lussac's test liquor. See Chloride of Lime and Inpigo. Wince the pieces through it for 40 minutes. Rinse again. 3. Peiss it again through the soap bath, No. 1. 4. Brigliten it in a large bath of boiling water, containing 4 pounds of soap, and 1 pound of a cream-consistenced salt of tin, containing nearly half its weight of the muriate of tin, combined with as much nitric acid of spec. grav. 1*288. This strong nitro-muriate having been diluted with a little water, is to be slowly poured into the bath of soap water, and well nixed by stirring. The pieces are now put in, and winced tnrough it for one half or t'ni-2e quarters of an hour. 5. Repeat the soap boil, No. 1. Rinse and drj'. 9. Grounding-in of Indigo blue. Take half a gallon of water of 120° F., 8 ounces of ground indigo, and 8 ounces of red sulphuret of arsenic (orpiment), 8 ounces of quicklime, mix together, and heat the mixture to the boiling point; withdraw from the fire, and add, when it is lukewarm, 6 ounces of carbonate of soda, stir and leave the whole at rest till the next day. Then decant the clear liquor, and thicken every quart of it with half a pound of gum. This color ought to be green, and be preserved in a close vessel. When used, it is put into a pot with a narrow orifice, the pencil is dipped into it, wiped on the edge of the pot, and immediately applied by hand. This plan is tedious, and is nearly superseded by the fol- lowing grounding blue. Take half a gallon of caustic soda ley of spec. grav. M5, heated to 120° F. 12 ounces of hydrate of protoxyde of tin, obtained by precipitating it from the muriate of tin by solution of potash. 8 ounces of ground indigo ; heat these mixed ingredients to the boiling point, then move the pot off and on the fire two or three times in succession, and finally thicken with 3 pounds of raw sugar. In order to apply this by the block, the following ap- paratus is employed, called the canvass frame; figs. 299,300. It is formed of a copper , ) \ CALICO-PRINTING. 321 ease or box A, in which is laid a frame b, filled with pretty stout canvass The box communicates by a tube with the cistern c, mounted with a stop-cock d. Fig. 300 represents the apparatus in plan : a, the box ; b, the canvass, with its edses a a a a, fixed by pin points to the sides. The color is ieared (tire), or spread even, with a wooden scraper as broad as the canvass. In working with this apparatus, the color being contained in the vessel c is drawn oflT into the case a, by opening the stop-cock d, till it rises to the level of the canvass. The instant before the printer daubs the block upon the canvass, the tearer (tireur), boy or girl, runs the scraper across it to renew its surface ; and the printer immediately transfers the color to the cloth. In this kind of printing great skill is required to give evenly impressions. As the blue is usually applied to somewhat large designs, it is very apt to run ; an inconvenience counteracted by dust- ing: fine dry sand upon the cloth as soon as it is blocked. The goods must be washed within 24 hours after being printed. 10. Topical grounding blue for the cylinder press. Take 3| gallons of caustic soda ley of spec. grav. 1*15. 3^ lbs. of ground indigo. 5 lbs. of precipitated protoxyde of tin (as above). Boil the mixed ingredients for ten minutes, take them from the fire, and add, first, 3 lbs. of Venice turpentine ; then 1 1 lbs. of gum. Put this mixture into the color trough, print with it, and after two days wash in the dash-wheel ; then pass it through a soap-bath, along with a little soda, to brighten the blue, and to take off' its grayish tint. The use of the turpentine is easily explained; it serves to exclude the atmospherical oxygen, and prevent the regeneration of the indigo blue, before it is spread upon the cloth. After the application to white calico of a similar blue, into which a little acid muriate of tin has been put, the goods are dipped for ten minutes in thin milk of lime, shaking the frame all the time. They are then washed, and cleared with a soap boil. The fol- lowing color remains long in the deoxyuized slate from its containing 8 ounces of indigo, 10 ounces of hydraled protoxyde of tin, and I| pounds of solution of muriate of tin, to 2 quarts of soda ley of 1*15, thickened with 2| pounds of gum. This blue may be applied by either the block or the cylinder. 11. Topical Prussian blue for grounding. 2 quarts of water with 8 ounces of starch are to be mixed and boiled ; add 2| ounces of a liquid Prussian blue color, prepared by triturating three quarters of an ounce of that pigment with as much muriatic acid, leaving the ingredients to react upon each other for 24 hours, and then adding three quarters of an ounce of water. Ad ] 4 ounces of liquid perchloride of tin (oxymuriateX Mix all together, and pass through a scarce. This color is not very fast ; cloth printed With it will bear only rinsing. 12. Prussian blue figures are impressed as follows : — Dissolve 8 ounces of sulphate of iron, and as much acetate of lead, separately in 2 quarts of boiling water ; mix well, and settle. Take one quart of this clear liquor re- duced to spec. grav. 1*02, one quart of mucilage containing 3 pounds of gum, colored with a little prussiate of potash, mix into a mordant, and print it on with the cylinder. Two days afterwards wash in tepid water containing a little chalk, and then pass the cloth through a solution of prussiate of potash in water, sharpened with a little muriatic acid, mi It takes the desired hue. Finally rinse. II. The padding or plaquage style, called /ott/ard also by the French. See Padding. Any mordant whatever, such as the acetates of alumina, or of iron, or their mixture, "»ay be applied to the piece by the padding machine, after which it is dried in the hot FLUF washed, dunged, dyed, washed, and brightened. .j.p'? \""T J^eta"ic oxydes are very elegantly applied by the padding process. Thuf «ie iron puft, the manganese bronze, and the chrome yellows and greens are given. i. Iron bufl^ or chamois. * ake 50 gallons of boiling water ; 150 pounds of sulphate of iron ; dissolve along with 10 pounds of alum ; which partly saturate by the gradual addition of o pounds of crystals of soda; and in this mixture^dissolve I im CALICO-PRINTING. • 50 pounds of pyroligneous acetate of lead. Allow the whole to settle, and draw ofl' tho clear supernatant liquid. For furniture prints this bath should have the spec. grav. 1*07. The calico being padded in it, is to be dried in the hot-flue ; and after 48 hours suspen- sion is to be washed in water at HOP containing some chalk, by the wince apparatus. It is then washed, by the same apparatus, in hot water, containing a pailful of soda ley of speo. grav. 1*04. For light tints the padding liquor should be rediiced to the spec. grav. 1-01. The ''t of the fibres and, on exposure to aur, absorbs oxygen, so as to become msoluble and fixed within their pores. On dipping the calico into the second vat of sulphate of iron, a layer of oxyde is formed upon its whole surface, which oxyde exercises an action only unon those parts that are covered with indigo, and deoxydizes a portion of it; thue rendering a second dose soluble by the intervention of the second dip m the hme-bath. Hence we see that while these alteniale transitions go on, the same series of deoxydize- ment «!olution, and re-oxydizement recurs ; causing a progressively increasing fixation of indigo within the fibres of the cotton. A deposite of sulphate of lime and oxyde of iron necessarily falls upon the cloth, for which reason the frame should be shaken in ti.e lime-water vat, to detach the sulphate ; but, on the contrary, it should be held motionless in the copperas bath, to favor the deposition of as much proloxyde upon it as possible. These circumstances serve to account for the various accidents which sometimes befall the China blue process. Thus the blues sometimes scale off, which may proceed from one of two causes :— 1. If the goods are too dry before being dipped, the color swells, and comes off in the vats, carrying along with it more or less of indigo. 2. If the quantity of sulphate of lime formed upon the cloth be considerable, the crust will fall off, and take with it more or less of the blue ; whence arise inequalities in the impression. The influence of temperature is important ; when it falls too low, the colors take a gray cast. In this case it should be raised with steam. , v v VI. The decoloring or enlevage style ; not by the removal of the mordant, but the destruction of the dye. The acid, which is here mixed with the discharge paste, is intended to combine with the base of the chloride, and set the chlorine free to act upon the color. Among the topical colors for this style are the following :— 1. Black.— Take one gallon of iron liquor of spec. grav. 1*086. One pound of starch ; boil together, and while the paste is hot, dissolve in it One pound of tartaric acid in powder ; and when cold, add Two pounds of Prussian blue, prepared with muriatic acid, see p. 232. Two ounces of lamp black, with four ounces of oil. 2. White discharge,— T^ke one gallon of water, in which dissolve One pound and a half of oxalic acid, Three pounds of tartaric acid ; add One gallon of lime-juice of spec. grav. 1'22; and thicken with Twelve pounds of pipe clay, and six pounds of gum. a. Chf>me-green discharge. — . , « * * u Take one gallon of water, thicken with 18 ounces of starch ; boil and dissolve in the hot paste ; Two pounds and a half of powdered nitrate of lead. One pound and a half of tartaric acid. Two pounds of Prussian blue, as above. 4. Blue discharge.— Take one gallon of water, thicken with 18 ounces of gum ; while the boiled paste is hot, dissolve in it Two pounds of tartaric acid, and mix one pound of Prussian blue. 6. Chrome-yellow discharge. — This is the same as the chrome-green given above, but without the Prussian blue. 6. jS white discharge on a blue ground requires the above while discharge to be strength ened with 8 ounces of strong sulphuric acid, per gallon. 7. White discharge for Turkey red needs to be very strong. Take one gallon of lime-juice of sp. grav. 1-086 ; dissolve in it Five pounds of tartaric acid ; thicken with Eit'ht pounds of pipe-clay, four pounds of gum ; then dissolve in the mixture Three pounds of muriate of tin in crystals ; and add, finally. Twenty-four ounces of sulphuric acid. 8. Yellow discharge for Turkey red. — Take one gallon of lime-juice of spec. grav. 1*086 ; in which dissolve Four pounds of tartaric acid. Four pounds of nitrate of lead ; thicken the solution with Six pounds of pipe-clay, and three pounds of gum. !». For green discharge^ add to the preceding 24 ounces of Prussiar Mue, as above. The decoloring or chloi-inc Nath l« usually formed of wood lined wi»li lend, and has an area of about 5 feet squire, with a de^^th of 6 Itet. A s ■ » Dry in the hot flue ; and after hanging up the goods during 3 days, wince well through chalky water, and then dye, as follows : — For each piece of 28 or 30 yards, 8 ounces of cochineal are to be made into a decoc- tion of 2 gallons in bulk, which is to be poured into a kettle with a decoction of 3 ounces of galls, and with two ounces of bran. The pieces are to be entered and winced as in the madder bath, during two hours and a half; then washed in the dash wheel. On mix- ing with the amaranth bath a certain quantity of logwood, very beautiful lilachs and vio- lets may be obtained. Mixture of quercitron and cochineal. — Pad in the aluminous moi-dant, and dye with 2 lbs. of quercitron, and 4 ounces of cochineal, when a capuchin color will be obtained. If we pad with the following mordant, viz., 1 gallon of acetate of alumina of 1-056 spec. grav., and 1 of iron liquor of 1-02 spec, grav., and dye with 1 pound of quercitron, and 1 ounce of cochineal, we shall obtain a shade like boot- lops, of extreme vivacity. Two ounces of cochineal will print a long piece of calico with rich pink figures, having acetate of alumina for a mordant. As the ground is hardly tinged by the dye, it neither needs nor admits of much clearing. I have already mentioned that goods are sometimes padded with solution of perchloride of tin before printing-on them the steam colors, whereby they acquire both permanence and vivacity. I have also stated that the salts of tin at a high temperature are apt to corrode the fibre of the stuff, and therefore must be used with discretion. This danger is greatly lessened by adding to the perchloride of tin a sufficient quantity of caustic potash ley to form a stannate of potash. The goods are padded through this substance, diluted with water, dried with a moderate heat, and then immersed in very dilute sul- phuric acid, which saturates the potash, and precipitates the tin oxyde within the pores of the cloth. Calico thus prepared aflTords brilliant and permanent colors by the steam pro^ cess, above described. Printing of silks or u^llcn stuffs, such as merinoes and mousselin de laine, as also of mix- ed stuffs of silk and wool, such as chalys.—AW these prints are applied, not by the cylin- der but the block, and are fixed by the application of steam in one of four ways ; 1. By the lantern ; 2. By the cask; 3. By the chest ; or, 4. By the chamber. 1. By the lantern.— In this mode of exposure to steam, the goods are stretched upon a frame ; and therefore the apparatus may be described under two heads ; the lantern and the frame. The former is made of copper, in the shape of a box a b c d ^,Jig' 301, open below, and with a sloping roof above, to facilitate the trickling down of the water con- densed upon the walls. The sides b c d e are 4| feet high, 6 feet long, and 4 feet wide. The distance of the point a from the line e b is 2 feet. At f is a brass socket, which may be stopped with a cork ; and there is a similar one at the other side. This kind of penthouse may be raised by means of a pulley with cords fixed to the four angles of the roof e b ; and it rests upon the table g h, a little larger than the area of the box, which stands upon the four feet i k. Round the borders of the table there is a triangular groove a b, for receiving the lower edges of the box, and it is stuffed steam- tight with lists of cloth. Through the centre of the table, the two-inch steam pipe M — <>A4 332 CALICO-PRINTING. ffc'eaua?dktST*'rr^'' * hemispherical rose pierced with nomerous holes fo, me equal distribution of the steam. Right above it, a disc n is placed upon four feet -^ The tube l communicates with a box p, which has a syphon q to let off the condensed water. At the upper part of this boy the tube l terminates which brings the steam. The little table G H slopes towards the part g, where the syphon r is placed for drawing off the water. The frame has such dimensions, that it may stand in the four corners of the table at s s, as pointed out by the dotted lines. Ihe second part embraces an open square frame, which is lonned by spars of wood 2 inches square, mortised together • and IS 3 feet 8 inches wide, 5 feet 8 inches long, and 4 feet 3 inches high ; it is strengthened with cross bars. Upon the two sides of its breadth, two rows of round brass hooks are placed about half an inch apart; they are soldered to a copper plate fixed to uprights by means of screws. . Before hanging up the goods, a piece of cloth 3 feet 8 inches long, and 4 feet wide, is placed upon the row of hooks : and 3 feet of It are left hanging out. .M?''*'rv "^'^^.^^^ ^*^°^^^ P^^^ '^''0"Sh the cloth. A similar one is fitted to the othei VfJ!' Ju ° ^ *^ intended to cover the goods hung upon the hooks ; and it is kept straight by resting upon strings. The pieces are attached zig-zag from one hook To another. When the frame is filled, the bag is put within the clotlis ; It haMh. sa^e rec^ tangular shape as the frame. The pieces are in this way all incased in the ck!h? a Wt ilru ' P"' beneath to prevent moisture affecting that part arP dn?hl!!}?"lf ^^T^'^'l^!?; T- ^"^"^^^ ^'^^ P^"^^ 5 and if they be too large, they are doubled back to back, with the fringes at top. » > * '^/ oJnlll ^''^Y!^^''^^ ^^'"^ T^-^' ^h ^'"^™^ •' ^^^ "P°" t^e taWe, the penthous; is pla- ItLolt %r^ %^ '^'^•" '' ^'^"J^"'^. ^""'^^ ^'"""^ 3^ *« 4^ ^i""^^^> ^<^<^°'-ding to circuit stances. The orifice f is opened at first to let the air escape, and when it begins to dis- charge steam it is stopped. The frame is taken out at the proper lime, the baV?s rt moved, the cloths are lifted off, and the goods are spread out for airing. Three\am« Sfui:Hy':.Sa\7e7ol"sLl^ ' ""'^'^^ ^"""^^^'^ ^'"^^'- ^^^ above apparatus is par- nr^^K^^"" '^''T*;^'^ u^ K^\^ ^°^' ^'™P^^ "'^^^ ""^ steaming. The apparatus is a drum of white wood, 2 inches thick,y?g. 302 ; the bottom is pierced with a hole which admiS the steam-pipe f, terminating in a perforated rose. Four inches from the bottom there IS a canvass partition e, intended to stop any drops of water projected from the tube r and also to separate the condensed water from the body of the apparatus. The drum is covered m by a wooden head h, under which the goods are placed. It is made fast either by bolts, or by hooks, g g, thus oo , to which weighted cords are hung. The frame 1, Jig. 302, rests upon a hoop, a a, a few inches Irom the edge. The goods are hung upon the frame in the or- dmary way, and then wrapped round with flannel. The frame is studded with pin points, like that of the indigo vat, fixed about 5 inches asunder. From 20 to 30 minutes suffice for one steam- ing operation. The upper part of the frame must be covered also with flannels to prevent the deposition of moisture upon it. At the bottom of the drum there is a stopcock to let off the con- densed water. According to the size of the figure, which is 3 feet 2 inches, 50 yards may be hung up single; but they may be doubled on occasion. iA ^y^ ^^^ / St 3. The box.— This steaming apparatus is convenient from the large quantity of goods admis- sible at a time : it answers best for woollen stuffs. From 12 to 16 pieces, of 36 yards each, may be operated upon at once ; and from 240 to 260 shawls. It it formed of a deal box, a b cb, fig, t.:^\, Vu ~ — J , . " 4.1. ,. . , » . , ~ 304 4 feet wide, 6 Ion?, and 3 wwA ^ T^^^'^V^iJ^'^l^fK*^!?- ? ^' ^^'^'"'^ *»y "^ *^°^"°^ the same substance, j, which is made steam-tight at the edges by a list of felt. The lid is fastened down bi 5 cross bars of iron, a a a a a, which are secured by screws, ccccc^fig. 806. The ends of these cross bars are ,et into the notches, bbbbb, on the edge of the box The safetr valve M,fig. 304, is placed upon the lid. For taking off the lid, there are rings at the fou \ k CALICO-PRINTING. 333 immcrs d d d d, bearing cords, f r f f. These join at the centre into one, which passef over a puUey. Eight inches from the bottom of the box there is a horizontal canvass par '^ ••■'•'■" "" 806 d EZCD 305 tition, beneath which the steam is discharged from the pipe l, fig. 306. There are two ledges, E F G H, at the sides for receiving tie bobbins. T/j2 tube l runs round the box, as shown by the letters d a eb : the end d is shut ; but the side and top are perforated with many holes in the direction towards the centre of the box. Fig. 305 shows the arrangement of the lower set of bobbins : that of the upper set is shown by the dotted lines : it is seen to be in an alternate posi- tion, one lying between two others. They are formed of pieces of deal 4 inches broad, 1 inch thick, and of a length equal to the width of the box. They are first wrapped round with 5 or 6 turns of doubled flannel or calico : the piece of goods is laid over it upon a table, and then wrapped round. At the end of the piece, several folds of the covering must be put, as also a roll of flannel. The two ends must be slightjy tied with packthread. When these flat bobbins are arranged in a box, the steam is let on them, and continued about 45 minutes ; it is then shut off, the lid is removed, and the pieces are unrolled. 4. The chamber. — ^The interior height of the chamber, a b c Djfig. 308, is nine feet, the length 12 feet, and the breadth 9 feet. The steam is in- troduceid into it by two pipes, ab Cy d ef. Their two ends, d c, are shut ; but their sides are all along perforated with small holes. The frames E F g H, E F g H, are moveable, and run upon rollers : they are taken out by front doors, which are made of strong planks, shut by sliding in _ slots, and are secured by strong iron bars and pressure screws. The cross rods, e r g h, are provided with hooks for hanging up the pieces. There is a safety-valve in the top of this large chamber. The dimensions of the frame are ten feet Ion?, 3 feet wide, and 7 high. Three feet and a half from the uppei part of the frame, a row of hooks is fixed for hanging on a double row of pieces, as shows in the figure. Over the frame, woollen blankets are laid to protect it from drops of wa- ter that might fall from the roof of the chamber. When the hooks are two thirds of an inch apart, 24 pieces, of 28 yards each, may be suspended at once. The period of steam- ing is from 45 to 60 minutes. Muslins and silks do not require so high a temperature as woollen goods. When the stuffs are padded with color, like merinoes and chalys, they must not be folded together, for fear of stains, which are sometimes occasioned by the column in steam calico-printing, "Where the end which receives the first impression of the steam is seldom of the same shade as the rest of the roll of goods. The duration of the steaming depends upon the quantity of acid in the mordant, and of saline solution in the topical color; the more ot ■which are present the shorter should be the steaming period. A dry vapor is requisite in all cases ; for when it becomes moist, from a feeble supply or external condensation, the goods become streaky or stained by the spreading of the colors. ^ 1. Black figures are given by decoction of logwood thickened with starch, to which a little oxalic acid is added whUe hot, and, after it is cold, neutralized solution of nitrate of iron. 2. Dark blue for a ground. — Decoction of logwood, and archil thickened wilh starch t to which, while the paste is hot, a little soluble Prussian blue is added ; and, when it ii cold, neutralized nitrate of iron ; see supra. 334 CALICO-PRINTmG. .xalic'aXfd re^hi7r?rS".r ""'' -^"'-j' «^-=>'»ed with starch , .o .he paste add may be used instead of the £,Ltion rf i^T/r '"f '".■"^- • '^^^ ^"^"^'"^ ••'»« 13. £™e™M ^_o„fZa^?„f'H'' '?'•'"!« «?Mi alum; thicken with gum. ries; MuartofE^nofLSof If?'''""'"'"',''!"''' '" ' P""""" »f Persian ber- it, with a ouarter of » r,n,,nH „r . /' ?>««, tied up in a Imen bag, are put into If the silkTTndian half an ou^^^'J^r"'' ^T^ "'' '^^' »"'' "« '"'W for 3 ho^r^? are taken out, the are rLl^ ?„ ?f ^ soda crjstals must be added. When the goods 8 ounces of crXliZi : o uJloT'a's \" ^1%^ """ "" '^"° ^^ "-^^^ water, and steeped in water verv fain r»?,vi,lf ^ -f^ ^^^J *''= "'"^ "»««^'' '■> eoW then rinsed, and dried. ^ ^ acidulated with sulphuric acid, during 4 hours, f ;Z''d^ra:{,a1^°;n:ad~4' o':,I'c?, % '"?'•'' ™f" ■• ^ •»»'"J^ T-J™ = -fi-lve : .ner''decompositrn':n°d'irblidet:,X:'„ff cleT'""' ' "'"""^' '»^"^'' 'o^""-! .ing«lWi;rdS^c™o„1f'B:a:nTcJ°tflrk^ -UhM ounces of starch, and the above red, 4 ounces of sulphite o'f copper ' ''*""^' ''''^'™' '» » S"^"" "f , in which steam may circulate, introduced by the pipe i ; the ex- cess being allowed to escape by the tube j, as also the water of condensation. The frame is placed in the hollow box k k. Between two such frames there is a plate of copper, l, which closes the box ; , it serves for laying the plates in order to keep them not. At E and h are prolongations of the box, in which are set the vessels f g for hold- mg the reserve paste. Preparation of the reserve or resist paste.— Melt in a kettle 2^ lbs. of rosin; 1 ». of suet; mix well, and put it into the basins f g'. By means of steam the reserve IS kept melted, as well as the false color upon which the sieve floats. The piece of silk being laid upon the table, and the reserve spread upon the frame, the printer heats his block, which sUould be mounted with lead, if the pattern will per- mit, upon the little table l. He takes up the color from the frame, and transfers u insiantly to the piece. He must strike the block lightly, and then lift it, lest, by its cooung, It might stick to the silk. When the table pattern is completed, he dusts it «ver with sand, and proceeds to another portion of the silk. The piece must not b« 336 JALICO-PRINTING. taken out of the stretch till it is quite dr>', which requires usually 6 hours. Let us con- sider first the most common case, that of a white upon an orange ground. We shaL afterwards describe the other styles, which may be obtained by this process. The piece, being printed and dry, must next be subjected to the mandarining operation. 322 ^ The apparatus here employed consists of a sandstone trough A B c D, fig. 312. Upon the two sides, a c, b d, of this trough n are fixed two wooden planks, pierced with a hole an inch from the bottom to receive the roller e, under which the piece passes* In this trough the acid mixture is put. That trough is put in- to a wooden or copper trough, f g h i. Into the latter, water is put, which is heated by means of steam, or a convenient fur- nace. Before and behind are placed two winces, or reel?, k l ; one serves to guide the piece in entering into the trough, and the other in its leaving it. The piece falls immediately into a stream of cold water, or, failing that, jnto a large back, con- taining a mixture of chalk and water. The two winces are moved by handles : the velocity is proportioned to the action of the acid. The wince l ought to be higher than k, to allow the acid to drain off. Fig. 313 shows a section of the apparatus. The temperature of the acid mixture ought to be maintained between 95° and 100** F. ; for if it be raised higher, the resist would run the risk of melting, and the impression would be- come irregular and blotty. The proportions of the acid mixture are the following : — 1 gallon of water ; and 1 gallon of nitric acid, of spec. grav. 1-288, which may be increased with the strength of the silk. It should be a little weaker for chalys. For the strong greens it may be 2 measures of acid of 1'288 to 1 measure oJ water. The duration of the passage through the acid should be 1 minute at most. Mixture of orange color^ and clearing away of the resist. — The goods, on coming out of the mandarining apparatus, are rinsed in running water; then boiled in soap water, quickened with a little soda, at the rate of 2 lbs. of the former and 4 oz. of the latter for a piece of 30 yards. They must be worked by the wince for half an hour. They are now rinsed in cold water, then passed through hot, again rinsed, and dried. I shall give some examples of the mode of manufacture, which is undoubtedly one of the most curious applications of chemical ingenuity. 1. Orange ground with white figures, (1.) Print-on the fat reserve; (2.) mandarine; (3.) brighten the orange, and clear. 2. Orange ground with blue figures. (1.) Dip in the indigo vat as for calico; (2.) print-on the fat resist to preserve the blue; (3.) mandarine; (4.) clear, and brighten the orange by the boil. 3. Orange ground, with blue and white figures. (1.) Print-on the resist to preserve the white ; (2.) dip in the vat, rinse, and dry ; (3.) ground-in the fat resist to preserve the blue; (4.) mandarine; (5.) cleanse, and brighten. 4. Fxill green ground, and white figures. (1.) Print-on the resist; (2.) mandarine, and rinse without drying; (3.) dip in the blue vat; (4.) cleanse, and brighten. 6. Full green ground, and blue figures. (1.) Dip a pale blue, rinse, and dry ; (2.) print-on the fat resist; (3.) mandarine, wash and dry; (4.) dip full blue; (5.) clean, and brighten. 6. Full green ground, with white and blue figures. (1.) Print on the resist ; (2.) dip a pale blue, and dry; (3.) ground-in the fat resist; (4.) mandarine and rinse ; (5.) dip a full blue ; (6.) clean, and brighten. 7. Full green ground, with white, blue, and orange figures. (1.) Print-on the fat reserve ; (2.) dip a pale blue, anddiy; (3.) ground-in the re serve; (4.) mandarine, rinse, and dry; (5.) ground-in the reserve; (6.) dip a full blue; (7.) clean, and brighten. If blue grounds with white figures be wanted, the resist must be applied, and then Che goods must be dipped in the blue vat : the resist is afterwards removed by a boil in Boap-water. The above processes are applicable to chalys. The property which nitric acid possesses of staining animal matters yellow, such as iiie skin, wool, and silk, is here applied to a very elegant purpose. Of the bronze or solitaire style by mandarining. — The mandarining mixture is 1 gallon of nitric acid, of 1*17 spec, grav.; mixed with 3 pints of solution of nitrate of iron, of spec. grav. ]*f>5. If the quantity of nitrate of iron be increased, a darker tint will be obtained. The temperature of the mixture should be 94® F. The pieces, after mandarining, are let fall into water, anii steeped for an hoar. CALICO-PRINTING. 337 In order to raise the bronze, and clear away the fat resist, the goods mujt be boiled ii a bath of soap and soda, as described for orange. 1. Bronze ground, with white fibres. (1.) Print-on the fat resist; (2.) dip in the blue vat, and dry ; (3.) pad in a decocaon of logwood of 4 lbs. per gallon ; dry, taking care to turn over the selvages; (4.)manX nne, and steep m water for an hour; (5.) cleanse, and pass through soa^. ^ 2. Bronze ground, vnth blue figures. & i • (1.) Dip in the blue vat, and dry ; (2.) print-on the fat resist; (3.) pad in the abov» brfghtn? ^^ ' ^''' ^^'^ °^^^d^""e, and steep an hoir;' (5.) cleanse, aS 3. Bronze ground, with white and blue. (1.) Print-on the fat resist ; (2.) dip in the blue vat, and dry ; (3.) ground-in the fat re- s^t; (4.) pad m the logwood liquor, and dry; (5.) ^andariJ^ and steep for an hoiJ^ (6.) cleanse, and give the brightening boil with soap. ^ ' This style of manufacture maybe executed on #.>iaivc. ^^a :„ i^i ,. ■, . beautiful effects which will in vJn be'^t foTbf l'^' ^fn^ "^'^''^ ^' ^'^""^"^ With silks, advantage may be derived from various metallic ^solutions which nossess the property of staming animal substances; among which are nitrate of silTernitm^ of LTr7n'te7-on"""'' '' "'" ^'^ ^^^"^'^"^ '' ^^^^^ '^'^ ^^^ ^^ thlktTd'w/^T^ ^n orange upon an indigo vat ground.-Kdtv the blue ground has been dyed oranee figures may be produced by printing-on the foUowin? discharge paste -- ^ 16 toll^onLrnr'nT-^ into a paste with 1 pound of starch ; when cold, add to it from ^.!:^^^i^ sirbo^ii.^"" "'''' ^'"^ ^^"'^ ''^ ^°'- ^^ ^^^-" ^rZ^^::^^'^^^ ^-^anblue In A caustic ley being prepared, of 1-086 specific gravity, disso'lve in a Mllnn nf ;, o pounds of annono and thicken with 3 pounds and? qui'ter of gum Two days aft" the impression of this paste, pass the goods through steam, and wash therin Junnin^ When a uniform color is to be anolied to both siVIpc nf «Ko -i««V .1. jj- employed; but, when only one sideTs "o b^'i;':' ^^^reS d agotuint^'re'ct Sdr/tc/htoL'-d"- '""'-'' -opicjaratpj";^ ^^- anJfh/hf ^f ''-^^r P'^!,^^ ^^'^°^ ^^^I'^^* stuff placed between the cloth to be printed and the block printmg-table or the cylinders. It should be kept very clean because of alumin^' ^^'' '"'"'' '' "'''' '' "^"^' '^''' ^" ^^^ ''^^"^^ ^^^^^ i^ade wilh acS iUamll?! ^'^'' \^^ color shop of a print-house are best made of wool, formed into a sub. stantial conical cap by felting. A filter ought to be set apart for each dTfSren dve .tuff When the goods al\er dyein- are washed, by bein- held bv ihT^Jtll v a 1 Rust stains are removeable by a mixture of oxalic and muriatic acids ToSf \;\r ^^ ^^ '^"'^^"?,^ ""''r '^ ^^^^"'^^ «^ 1'^- anTmuriaUc'acid CLili.^ '""Ti "/ ^fl'^"^ ^J'"'' ^y t^^ ^^^^ combination. Metallic greens and Scheele's green by the acid alone. after'ri^h'hTgoods munTwi^h'd "^llf ""%"^^ '^ ^^^^" '^ ^^ ^ --»- «'^«^»M 'nixture of oxairand muriatio «^- 1 '' ^^u '^f'^^^^y ^^^^ ^^ain may be removed by the The stains on sk and woolTpn .f^ ' ., ^^.^^ "^^^^^^'^ ^^^^' t« '^^"on and linen, •oap bo 1 whirh nfnv .1 n u"^' '^^'"^^ ^^ ^^"^''^^'^ ^^^^'^ ^xing the colors by the little wat^J ^ ^ ''^"^ ^' '^""^ ^y scratching with the finger, with the aid of a Vm V""^*"' *'*^**''' ^^^"' ^^^ °^y^e of Chrome. ^^' 2X 338 CAUCO PRINTING. CALICO PRINTING. 339 ; f t Mr. Hudson, of Gale, near Rochdale, obtained a patent, in December, 1834, for a me- chanism which furnishes a continual and regular supply of color to the sieve or tear {tire, Fr.), into whicli the printer has to dip his block, for the purpose of receiving the color about to be transferred to the fabric in the operations of printing calicoes or paper hangings. The contrivance consists in a travelling endless web, moved by power, which, by passing progressively from the color vat over the diaphragm, brings forward continu- ftiuly an equable supply of the colored paste for the workman's block. 314 ^ ^ig. 814 represents the construction of this inge- nious apparatus, shown partly in section, a a is « vessel of iron, supported upon wooden standards b b, over the upper surface of which vessel a sheet or diaphragm, c c, of oiled cloth, or other suitable elastic material, is dis- tended and made fast at its edges by being bent over a flange, and packed or cemented to render the joints water-tight. A vertical pipe d is intended to conduct water to the interior of the vessel a, and, by a small elevation of the column, to create such upward pressure as shall give to the diaphragm a slight bulge like the swimming tub. An endless web, e e e, passing over the surface of the diaphragm, is distended over three rollers, /g A, the lower of which,/, is in contact with the color-roller t in the color- trough K. On the axle of the roller i a pulley wheel is fixed, which allows the roller to be turned by a band from any first mover ; or the roller may receive rotatory motion by a winch fixed on its axle. On this said axle there is also a toothed wheel, taking into a another toothed wheel on the axle of the roller/; hence, the rotation of the color-roller t in the one direction- will cause the roller / to revolve in the opposite, and to carry for- ward the endless web e e e, over the elastic diaphragm, the web taking with it a stratum of color received from the roller i, evenly distributed over its surface, and ready for the printer to dip his block into. The axles of the rollers/ and g turn in stationary bearings ; but the axle of A is mounted in sliding nuts, which may be moved by turning the screws in, for the purpose of tight- ening the endless web. The axle of the color-roller i turns in mortises, and may be rais- ed by screws w in order to bring its surface into contact with ihe endless web. To pre- vent too great a quantity of color being taken up, the endless web passes through a long slit, or parallel aperture, in a frame o, which acts as a scraper or doctor, and is adjusta- ble by a screw p, to regulate the quantity of color carried up. The contents of the vessel a, and of the color-trough fc, may be discharged when required by a cock in the bottom of each. See Paper Hangings, for the Fondu style. Tne outside working gear of the four-colour calico printing machine, is shown in Jig. 315., where a, a is a part of the two strong iron frames or cheeks in which the various rollers are mounted. They are bound together by the rods and bolts a, a, a. b is the large iron pressure cylinder, which rests with its gudgeons in bearings or bushes, which can be shifted up and down in slots of the side cheeks a, a. These bushes are suspended from powerful screws, b, which turn in brass nuts, made fast to the top of the frame a, as is plainly shown in the figure. These screws serve to counteract the strong pressure applied beneath that cylinder by the engraved cylinders d, e. c, D, E, K, (see Jig. 297.) are four printing cylinders, named in the order of their opera- tion. They consist of strong tubes of copper or gun metal, forcibly thrust by a screw {)re8S upon the iron mandrels, round which, as shafts, they revolve. The first and last cy- inders, c and f, are mounted in brass bearings, which may be shifted in horizontal slots of the frame a. The pressure roller b, against whose surface they bear with a very little obliquity downwards, may be nicely adjusted to that pressure by its elevating and depressing screws. By this means c and f can be adjusted to b with geometrical precision, and made to press it in truly opposite directions. The bearings of the cylinders d and e are lodged also in slots of the frame a, which point obliquely upwards towards the centre of b. Tlie pressure of these two print cylinders, c and f, is produced by two screws, c and d, which work in brass nuta made fast to the frame, and very visible in the figure. The framework in which these bearings and screws are placed has a curvilinear form, in order to permit the cylinders to be readily removed and replaced, and also to introduce a certain degree of elasticity. Hence the pressure applied to the cylinders c and f partakes of the nature of a springs » circumstance essential to their working smoothly, notwithstanding the occasional inequalities in the thickness of the felt web and the calico. The pressure upon the other two print cylinders, d and e, is produced by weights acting with levers against the bearings. The bearings of d are, at each of their ends, acted upon b^ cylindrical rods, which slide in long tubular bosses of the frame, and press with their nuts g, at their under end upon the smaller arms of two strong levers «, which lie on each side of the machine, and whose fulcrum is at h (in the lower corner at the left hand). The longer arms of these levers, o, are loaded with weights, H, whereby they are made to press up against the bearings of the roller d, with any desired degree of force, by screwing up the nut g, and hanging on the requisite weights. ^ The manner in which the cylinder k is pressed Up against b is by a similar con- struction to that just described. With each of its bearings there is connected by the link k, a curved lever i, whose fulcrum or centre of motion is at o. Bv turning therefore, the screw m, the weight v, laid upon the end of the longer arm of the lever k (of which there is one on each side of the machine), may be made to act or not at plea- sure upon the bearings of the cylinder e. The operation of this exquisite machine IS minutely described m pp. 315, 316. A patent was obtained in August, 18.^9, by Mr. J. C. Miller of Manchester, for cer- tain improvements m prikimg calicoe«, consisting of a modified mechanism, by which tne same effect can be produced as by block printing. ^r,f^''}]^' ^7' ^1?' ^^e several views of this machine, calculated to print two pieces, or two different pat erns (on the same block) of calico, side by side, o^ four pieces, the from WoJkL "^""^^ intended device consisting of four colours to be prLted ^J}^' ^l^' ^^P^^^^®'^*^ *, ^'^^ elevation, f.g. 317. a front view, and Jig. 318. a trans- verse section, taken nearly through the middle of the machine. thli/. ^'rf *? framing is shown at a, a, supporting the colour boxes b, L k with Wieir doctors ; the furnishing tables or beds, c, c, c, (substitutes for the sieves in ordinary 2X2 340 CALICO PRINTING. CALICO PRINTING. 341 block printing) ; the printing table, d, d ; and the feeding, drying, and colouring The machine is also provided with a carriage, t, i, for the printing blocks, y, j, j. This carriage, i, i, travels m and out at suitable ihtervals upon rails, &, fc, attached to the mam irammg. The operation of the machine is effected bypassing a driving strap, Z, round the driving pulley m fixed at the extremity of the main driving shaft, «, n. At the other end of this shaft, the bevilpmion,o, IS keyed, gearing at suitable intervals with the bevil wheelj? which is mounted upon the end of the cross shaft q ; at about the middle of this shaft, the mitre wheels r, r, driving the upright shaft s, 5, and mitre wheels L L above, actuate, by means of the spur pinions u, u, the feeding rollers/,/, and thus d^aw the pieces of goods into the machine. Simultaneously with the progress of the cloth, the mitre wheels r, v, at the other end of the cross shaft g, drive the furnishing roUers w, w, w, by means of the spur gear- ^ng ar, X, X. The furnishing rollers, revolving in their respective color-boxes, spread or ?nl?pr «nVt w"^-\*-^' travelling endless blankets, y, y, y, which pass round the top roUer and the furnishing tables or beds, c, c, c, in order to supply the colors to the surfaces of the prin mg blocks, j, y, j. Either beds or the backs of the printing block! may be made slightly elastic, to insure the perfect taking up of the colors. Supposing the carriage, t, i, to be run out upon its railways, at the farthest point frort !nur whPPw' nnnn ^^^''Z''^ ^.'^^^y'd toward the fumishing beds c, c, by means of the spur-wheel X, upon the driving-shaft «, taking into a small pinion, 1 (shown by dots m fig. 17), upon the shaft, 2 On the end of this shaft is also keyed the mangle pinion 3 gearing in the mangle wheel, 4, which is keyed upon the end of the shaft! 5 Is^fil Id^^' spur-wheel, 6, in gear with the pinion, 7, made fast to the shaft, 5 Upon either end of the shaft, 5, is a rack pinion, 9, taking into the horizontal rack 10 made fast to the carnage-frame, i, i ; and thus the blocks j,j, are presented to the fur- nishing blankets y, y, y, and take a supply of colour ready for printing. The travelling- carriage and blocks now retire, by the agency of the mangle-wheel and pinion, 3 and 4 the pinion being fixed upon the end of the shaft, 2, and the wheel upon the other shaft in a line with the shaft 2. At this time another operation of the machine takes placa Upon the reverse end of the shaft 6, is a pinion, 11, gearing with the spur-wheel 12; and by means of the spur gearing, 6 and 13, and counter-shaf^ 14, the pinion 16, Zll t7Z^^4ra^^ft}' ^^' ^h^^\^«Fespond8 to the wheel, 12, on the other side of the machine^ To one of these spur-wheels are attached by bolts two quadrant levers. 17 17- and as these wheels revolve by means of the gearing just described, the eveS 17 17 ti: ornri,'trn?Ho\' •' ''1^''^^% t,h^ '---^ l^Vnd 20, and thus elevate Jhewhdi series of prmtmg blocks m the parallel grooves, 21, 21 ; at the same time pressing or dosing them mto one mass or block by expanding the springs, 22, 22 ; a^d at the nest of the carnage caused at a proper interval by the agency of the maS-wheel th* ~'dr^'' T^'''' '^- P"""'"^ "P^^ '^' «^^^^^^ «^*he goods afonl^ in fo^ Th 1 .f ^"""^ '"'i''^"'' ^/^ '" ?^ ^^^' «•• °^«^^ widths of cloth at one operatio^ The cloth IS now drawn forward for the space of the exact width of one of The blocks. Z^ aI "** ?^ 1^'!?°' ^^ ""."/^^ ^^ *^^ spur-wheels and pinions, 23, 23 and paS around heated cylmdera, g g, if necessary, and between the delivering roller^ out ofihe m n fT \ "°*'l *^^ P"""*'"^ '' completed ; the colours making a single advance 01 thc^ pattern at every presentation of the blocks, until the whol? number of bS i..t^ been presented to the same space or portion of the goods successively w^^h fi^ ^ • ^"^^^^.^^ carnage, is used for throwing the whiel » in and out of ceS woven of dead wool cannot be wpII AxroA ni^t^i. ^e ^- j ^v*""^**" v.w»,uv/u. vtuuub quire a n^^milmr fr-^airr.^r.i^f Ti^ X. ^^^^'^ **' mixcd cotton and wool yarns re- Mi ^Hn. ^LfKol? "^ *^^ ^^"^^ P"°^^^- ^^""^^ ^e with this preparation it is to be diluted to the desired degree, and put into the padding trough where it serves to impregnate the goods uniformly. They are then transferred to the stove where they are to be dried, but not to hardness, for fear of corroding the fibres by the red oxide of iron ; they are next passed through a peculiar padding machine containing a weak solution of carbonate of soda mixed with a little quicklime. In proportion as the cloth is passed through the bath, and its alkaline matter gets neutralized, it must be refreshed with fresh solution of soda. The cloth may be supplied by a soap-bath ; and lastly by the dash-wheel. If the iron orange tint is not sufficiently deep by one operation, it may be increased by another, and also rendered more uniform. A mixture of red muriate of iron and sal ammonia gives a good iron dye, and with perfect safety; or one of red sulphate and sal ammoniac. Goods padded in iron liquor, dried, and then padded in a solution of chlorine containing a little free- lime, acquire a good rurSt ground. The following prescriptions serve as resist pastes for these dyes. In 9 quarts of hot water dissolve 5 lbs. of the biarsenate of potash, and add to the solution as much carbonate of potash as to give it a slight alkaline reaction. Dividing this liquor into two equal parts, there is to be incorporated with the first, 10 lbs. of pipe-clay, and to be dissolved in the second 4| lbs. of gum Senegal, with | of a pound of soft soap ; the two are to be united. This resist is to a certain degree of a mechanical quality, for the ferruginous preparation cannot touch it, without setting the fat acid of the soap at liberty and preventing the entrance of the liquor into the pores of the web. White resists on rust grounds are also made with a mixture of tartaric and oxalic acids; as also of lime juice. When the iron oxide is fixed, as in the genus avanturine, muriate of tin is a preferable discharge ; as for example : In 9 quarts of water diffuse 3^ lbs. of flour, 1 lb. of starch, and boil into a paste ; and add to 2 lbs. of this paste, 2 lbs. of acid muriate of tin at 65° B. (solution of salt of tin in muriatic acid.) This for printing with the block. For printing on the dis- charge paste by the cylinder, to 2 lbs. of the paste are to be added 4 lbs, of the acid muriate of tin at 65° B. In these preparations the combined action of the muriatic acid and muriate of tin is sufficient to displace the oxide of iron ; but the paste must not be left long exposed to the air, otherwise the iron may become fixed by peroxi- dizement. White discharge upon chamois (a faint rust colour) is produced by II lbs. of gum arabic, 2^ lbs. of oxalic acid, 2 lbs. of tartaric acid, | lb. of oil of vitriol After applying this discharge the goods should not be exposed to a high heat to dry them. The first of these two receipts tends to crystallize, the second to deliquesce. It deserves to be remarked, that when soda is employed to precipitate rust of iron upon goods, tlie tint is much deeper than it is by lime. Of the colours produced by the oxide of chroTne. — A preparation for this purpose is made by boiling together 2 lbs. of bichromate of potash, and 4 lbs. of muriatic acid. The muriatic acid excess is to be evaporated off. For obtaining deeper shades, arsenic acid is introduced in determinate proportions ; as for example : To 9 quarts of water, there are added 9 lbs. of bichromate of potash, 12 of arsenious acid, and 20 or 22 lbs. of muriatic acid, in oi'der to destroy all the chromic acid, and that the chlorine set at liberty in contact with the water and the arsenious acid may transform the last into arsenic acid by the oxygen of the decomposed water. When the reaction has ceased, a fine green liquor results, which is to be evaporated to the density of 60° or 65° B. to dissipate the free acid ; care should be taken to get rid of the acid excess either by a regulated heat or by soda. Man}' pieces of calico are dyed a fine green by the oxide of chrome, and are very fast. The solution of muriate of chrome, just described, at a density of 45° B., is to be thickened slightly with gum, poured into a padding machine, then dried carefully to aid the fixation of the colour, and finally passed through a weak bath of soda: to complete the deposition of the oxide of chrome, ammonia may be substituted for the carbonate of soda. The colours thus produced are pale green, or grey, but may be deepened by gassing the cloth through a weak bath of sulphate of copper ; it may be deepened also y mixing with arsenic acid, and after some days' repose, precipitating the ai'seniate of chrome on the stuff by passing it through a bath of carbonate of soda. Of the simple genera derived from oxide of manganese. — This colour is generally known by the name of solitaire bistre, and sometimes turks-head. By impregnating the cloth "with a neutral solution of acetate of manganese, then precipitating the oxide with an alkali, exposing the goods to the air to favour the oxidation, or passing them through a bath of chlorite of lime, the process of the manganese dye may be executed. After passing the goods through the manganese bath over 8 rollers, to secure uniformity of impression, they should be dried immediately in a stove. The d^e-bath should contain a small quantity of mucilage of gum arabic. The alkali for precipitating the oxide of manganese in the padding machine should be caustic, strong, and heated by a steam pipe to the boiling point. The strength of the alkaline solution should in all cases be 14° B. : and for some purposes even 22° B. This alkaline strength is requisite to seize the fibre the instant of the tissue entering the alkaline bath, and to force, by the contraction which it causes, the oxide of manganese to remain within it till the oxidation is com- pleted. It is obvious that the bath must be kept up by fresh alkali. The two last cylinders of the frame should be heavily loaded, so as to render the goods as dry as pos- sible. A passage through solution of chlorine is in general advantageous to complete the Vol. L 2 Y I il 346 CALICO PRINTING. CALICO PRINTING. 347 oxidation of the manganese. A more economical process would be to add an equiva- lent of sal ammoniac to an equivalent of chlorman^anese, and to make the solution alkaline with a little ammonia. The goods padded m this liquor might be dried with- out risk of injury, and be then finished in the baths, firat^ of milk of lime, and next of chlorine : or at once in a mixture of the two. The shades with a foundation of manganese are often modified in various ways ; as by adding to the mixture a certain quantity of acetate of lead, whence results chlorlead ; while in passing into the solution of chlorlime, the lead is transformed into peroxide, whose brownish yellow added to the tint of the manganese produces a yellowish cast and a velvety aspect. Sometimes some salts of iron are added, which decomposed and peroxidized along with the salts of manganese give shades which resemble aventurine, the more closely the larger the proportion of iron. PrusHan blue. — Its white discharge is effected upon calico, by preparing a rust ground of a proper tint for producing with acidulated ferrocyanure of potash the desired blue shade. Into either the mordant or into the ferrocyanide put the quantity of muriate of tin necessary to give the blue its purest tint. The discharge is performed usually at two operations, by the first the ferrocyanure is decomposed by a powerful base (potash), which forms a yellow cyanure, and liberates the iron oxide ; by the second, we remove the iron, by the intervention of an acid. But the success of this second operation depends on the energy of the first, and especially upon the washings which follow it, and which ought to have carried off the whole of the ferrocyanure ; otherwise the presence of the acid would regenerate the blue upon the points which should remain clear of it The pieces, after being dried and calendered, receive an impression with caustic potash ley (thickened with gum), and which in every case should mark at least 14° B., m order to make the texture contract or shrink suitably, and furnish a precise or sharp print It is then to be rinsed and washed in the dash-wheel so as to clear away every thing but the oxide of iron from the cloth upon all points touched by the alkali. The piece is then immersed in water acidulated with muriatic or sulphuric acid, till the oxide of iron has entirely disappeared. By adding to the potash a little tartrate of potash, the oxide of iron from the Prussian blue enters into combination with the tartaric acid,, and goes off in a great measure with the subsequent washings. This style may also be executed upon silk and woollen goods, but great precaution must be used to avoid injuring the texture by the strong alkaline ley. Silk handker- chiefs are first passed for about thirty minutes through a bath of nitrate of iron of 4° B. then through running water, next through the dash-wheels. They are next put in a bath of clear and cold lime water, in order to decompose the salt of iron, and to fix the oxide upon the stuff. It is now rinsed, and sent through the dash-wheel before proceeding to dye it; which is done by passing it through a tub sharpened with a little sulphuric acid, and containing a small quantity of ferrocyanure of' potash. After workmg the cloth fifteen or twenty minutes in this bath, a little more acid and ferrocyanure are in- troduced, and the passage of the cloth is resumed during fifteen minutes more, which time is usually sufficient to produce the desired tint It might be better to decompose {)reviously in a separate vessel the ferrocyanure by adding to one equivalent of it in so- ution two equivalents of sulphuric acid. The mixture of sulphate of potash and fer- rocyanic acid thence resulting, should be poured by degrees into the dyeing bath, till the due tint is produced, or the oxide of iron on the cloth becomes saturated. When the ground has been thus dyed, the discharge-printing may be proceeded with as already directed. Muriate of tin may sometimes be substituted for acid, for acidifying tlie ferrocyanure of potash in the act of dyeing. By substituting oxide of copper for oxide of iron, a crimson colour is obtained with the ferrocyanure. Saxoii Mice ; solution of indigo in ndphuric acid. This blue dye is given by passing the cloth mordanted with base of alumina through the indigo solution of a proper degree of strength. It enters also as an ingredient in certain pistachio green dyes. TJie genera of styles derived from madder are numerous. Plain grounds upon ordinary cloth ; albuminous mordant ^o* ; iron mordant, ^®* ; mordant of alumina and iron, . . ^<^' ; mordant of chrome. Plain printing; white reserve with mordants of alumina, iron, or chrome, do. white discharge upon common madder dye. do. white discharge on oiled cloth, with madder dye; mordants of iron (violet and lilac) upon the cy- linder. ^ There are, 1. 2. 8. 4. 5. 6. n. White ground; printing with alumina mordant for red and pink upon the cylinder White ground ; printing on mordants of alumina and iron. White ground; printing on mordants ; for red, violet, puce, black ; a binary, three- fold and fourfold union of these colours. White ground ; printing on mordants, for red, violet^ or puce ; separate or combined ; bv the block or Perrotine. Plain ground upon oiled mordanted cloth : with alumina of iron. Turkey red, or violet oiled. ., j wu White ground; printing with mordant of iron and alumina upon oiled cloth. The colours obtained directly by madder are red and its gradations, pale red and pinky ■which have always an aluminous mordant for their base ; black and its gradations : deep violet, light violet, and lilac, of which the base is pyrolignite of iron, or the common acetate ; red and deep puce, whose mordant is a mixture of aluminous and iron liquore ; lastly, the veiitre dc biclie fixed by means of the oxide of chrome. In every print woi-t, three principal mordants are prepared beforehand in a certain state of concentration, which are diluted when wanted with water, but more frequently with gum-water, and vinegar. ,- , ^ A. Mordant for red is made with 100 quarts of boiling water in which are dissolved 150 pounds of alum; and then 150 pounds of pyrolignite of lead added. B. Mordant for red, 100 quarts of water, in which are dissolved, 70 pounds of alum, 48 pounds of acetate or pyrolignite of lead, 2* pounds of car- bonate of soda (crystals), 4 pounds of muriate of soda. C. Mordant for red. _ - In 100 quarts of boiling water are to be dissolved, 66 pounds of alum ; and then to be added, 56 pounds of pyrolignite of lime, and 5 pounds of soda carbonate in crystals. Red Mordant ^, .,. . j j- i To 66 quarts of decoction of logwood, add 100 quarts of boiling water; and dissolve in this mixture 67 pounds of alum, 56 pounds of pyrolignite of lead, and 6 pounds of Other mordants are made of like quantity in which decoction of quercitron is put along with chlorzinc ; some into which an admixture of chalk is made, others with an admixture of acetate of lead, and some chalk. The blacks are made by strong mordants, with some salt of copper. Cochineal is used much in the same way as for the madder printing and discharges, and the mordants are much the same ; Brazil wood printing is of like nature : as also logwood dyes. The styles of printing derived from mixed colours are innumerable ; but all proceed on the principles already laid down. .. ^ ^i. Calico Printing by Steam.— AW textile fibres do not attract colouring matters to them with an equal poVer, but they may be rendered capable of acting with more or less force bv adventitious aids, of which the use of steam conjoined with the salts or oxides of tin forms two of the most remarkable. Tlie muriate or chloride of tin is decomposed by the action of water into muriatic acid and oxide of tin, the first of which is expelled by the heat of steam, or it may be neutralized by the intervention of a saturating substance ; while the second is never set at liberty in presence of cloth without making such a body with it as to resist all the means of discharge employed for the removal of the other substances, and without fixing at the same time on the fibres the colouring matter pre- viously mixed with it The same reasoning may be applied to the muriate of alumina. Oxalic acid fulfils at once the functions of these two saline compounds. It is an agent employed to remove the oxides or the mordants ; and this application is based upon the affinity which it has for alumina and iron. When deposited upon a mordanted cloth, it may either make the whole of the oxide disappear, if used in sufficient quantity, or it may restore it in whole or in part eventually, if the contact be prolonged at the ordinary teniperature or immediately when exposed to steam. It is thereby easy to explain certain phenomena, since by its energetically dissolving the oxides, it preserves them in solution during the whole period of printing them, and then quits them under the in- fluence of a steam heat ; and leaves them on the cloth in all their properties when alone. It is to this peculiar property of the oxalic acid that we must ascribe the solidity of certain topical blacks, for which it has been long employed. The tartrates and tartaric acid concur also to the same end ; but the athnity ot this acid for the bases, and the force with which it masks them, render its application more limited than the oxalic acid. It is useful for eflfecting displacements, and for preserving oxides in solution, so as to insure homogeneity to colours. , Acetic acid enters also as an ingredient into steam printing ; possessing a solvent 2Y2 348 CALOMEL. CALORIFERE OF WATER. 849 power difiFerent from the other acids, and being applicable in a state of concentration without corroding the tissues, it is applied in circumstances where «ubstances of a more or less resinous nature need to be kept in solution in order to being printed on ; whilst quitting under the influence of heat the bases with which it is associated, it allows them to contract an intimate union with the stuffs. The salts of copper and'chromate of potash are employed to perform the oxidizing power of the absent air. The colours fixable b}^ steam, after having been suitably thickened, are to be printed with the nicety appropriate to each, and the goods covered with them should be previ- ously exposed for some time to a damp atmosphere. In the steaming process, the goods are coiled round a perforated hollow cylinder charged with steam by a central pipe, or they are exposed on frames in single pieces without mutual contact in wooden cases filled with steam. Care must be had to prevent the dropping down of condensed steam upon the goods. When rolled up in a cylindrical form, they are wrapped in blanket stuff. Of late years contrivances have been made to keep the cloth moving in the steam so as to receive the equal benefit of its action. A great variety of other forms of this steam-bath are in use, according to the fancy of the operators. "But in all cases there should be a redundance of highly elastic steam, of vesicular quality, which is secured by causing it to bubble up through a stratum of water lying on the bottom of the case. CALOMEL. {Chlonire de Mercure, Fr. ; Vermsstes Quecksilber, Germ.) The mild protochloride of mercury. The manufacture of this substance upon the great scale may be performed in two ways. The cheapest and most direct consists m mixing 1| part of pure quicksilver with 1 part of pure nitric acid, of sp. grav. from 1-2 to 1-25; and in digesting the mixture till no more metal can be dissolved, or till the liquid has assumed a yellow colour. At the same time a solution of 1 part of common salt is made in 32 parts of distilled water, to which a little muriatic acid is added : and, when heated to nearly the boiling point, it is mixed with the mercurial solu- tion. The two salts exchange bases, and a protochloride of mercury precipitates in a white powder, which after being digested for some time in the acidulous supernatant liquor, is to be washed with the greatest care in boiling water. Tlie circumstances which may injure the process are the following :— 1. When less mercury is employed than the acid can dissolve, there is formed a deuto-nitrate of mercurj^ which forms some corrosive sublimate with the common salt, and causes a proportionaldefalcation of calomel. 2. K the liquors are perfectly neutral at the moment of mixing them, some subnitrate of mer- cury is thrown down, which cannot be removed by washing, and which gives a noxious contamination to the bland calomel, llie acid prescribed in the above formula obvi- ates this danger. The second manner of manufacturing calomel is to grind very carefully 4 parts of corrosive sublimate (bichloride of mercury) with 3 parts of quicksilver, adding a little water or spirits to repress the noxious dust during the trituration. The mass is then introduced into a glass globe, and sublimed at a temperature gradually raised. Th« quicksilver combines with the deutochloride, and converts it into the protochloride or calomel The following fonnula, upon the same principle, was recommended to the chemical manufacturer in Brande's Journal, for July, 1818: Prepare an oxysulphate of mercury, by boiling 25 pounds of mercury with 35 pounds of sulphuric acid to dryness. Triturate 31 pounds of this dry salt with 20 pounds 4 ounces of mercury, until the globules disappear, and then add 17 pounds of common salt The whole is to be thoroughly mixecf, and sublimed in earthen vessels. Between 46 and 48 pounds of pure calomel are thus produced: it is to be washed and levigated in the usual way." The above is the process used at Apothecaries' Hall, London. The oxysulphate is made in an iron pot; and the sublimation is performed in earthen ves- sela The crystalline crust or cake of calomel should be separated from the accompany- ing grey powder, which is nearest the glass, and consists of mercury mixed with cor- rosive sublimate. An ingenious modification of the latter process, for which a patent, now expired, was obtained by Mr. Jewell, consists in conducting the sublimed vapours over an extensive surface of water contained in a covered cistern. Thfi calomel thus obtained is a supe nor article, m an impalpable powder, propitious to its medical efficacy. The presence of corrosive sublimate in calomel is easily detected by digesting alcohol upon It, and testing the decanted alcohol with a drop of caustic potash, when the cha- racteristic brick-coloured precipitate will fall, if any of the poisonous salt be present To detect subnitrate of mercury in calomel, digest dilute nitric acid on it, and Uat the acid with potasli, when a precipitate will fall in case of that contamination. As it is a medicine so extensively administered to children at a very tender age, its purity ought to be scrupulously watched. r J & 118 parts of calomel contain 100 of quicksilver A patent was obtained in September, 1841, by Anthony Todd Thomson, M. D., for an improved method of manufacturing calomel and corrosive sublimate, as follows : — J. ■ ,. 1. # This invention consists in combining chlorine in the state of gas with the vapour of mercury or quicksilver, in order to produce calomel and corrosive sublimate. The apparatus employed consists of a glass, earthenware, or other suitable vessel, mounted in brick-work, and communicating at one end with a large air-tight chamber, and at the other end, by means of a bent tube, with an alembic, such as is generally used in generating chlorine gas. Tlie alembic is charged with a mixture of common salt, binoxide of manganese and sulphuric acid, or of binoxide of manganese and mu- riatic acid, in order to produce chlorine gas. The mode of operating with this apparatus is as follows : — ^A quantity of mercury or quicksilver is placed in the glass vessel, and the temperature of the same is raised to between 850° and 660° Fahr., by means of an open fire beneath. The chlorine gas, as it }B generated, passes from the alembic through the bent tube into the glass vessel, and there combining with the vapour of the mercury, forms either corrosive sublimate or calomel, according to the quantity of chlorine gas employed. The product is found at the bottom of the air-tight chamber, and may be removed from the same through a door, when the operation is finished. According to the patent of Mr. Josiah Jewell, the vapour of calomel was to be transmitted into a vessel containing water, in order to condense it at once into an impalpable powder. But this process was beset with many difficulties. The vapour of the calomel was afterwards introduced into a large receiver, into which steam was simultaneously admitted ; but this plan has also been found to be precarious in the execution. The best way is to sublime the calomel into a very large chamber from an iron pot, in the same way as the flowers of sulphur are formed. The great body of cool air serves to cause the precipitation of the calomel in a finely comminuted state. It ia afterwards washed with water, till this is no longer coloured by sulphuretted hydrogen. CALORIC. The chemical name of the power or matter of heat. CALORIFERE OF WATER. {Calorifere d*eau, Fr. ; Wasser-Heitzung, Germ.) In the Dictionnaire Technologique, vol. iv., published in 1823, we find the following de- scription of this apparatus, of late years so much employed in Great Britain for heating conservatories, &c., by hot water circulating in pipes : — "This mode of heating is analogous to that by stove-pipes : it is effected by the circu- lation of water, which, like air, is a bad conductor, but may serve as a carrier of caloric by its mobility. We may readily form an idea of the apparatus which has been employed for this purpose. We adapt to the upper part of either a close kettle, or of an ordinary cylindric boiler a, fig. 319, a tube b, which rises to a certain I height, then descends, making several sinuosities with a gentle \TJ 319 slope till it reaches the level of the bottom of the boiler, to whose ^^ lowest part, as that which is least heated, it is fitted at c. At the highest point of the tube r we adapt a vertical pipe, des- tined to serve as an outlet to the steam which may be formed if the temperature be too much raised : It serves also for the es- cape of the air expelled from the water by the heat : and it per- mits the boiler to be replenished from time to time as the water is dissipated by evaporation ; lastly, it is a tube of safety. "The apparatus being thus arranged, and all the tubes as well as the boiler filled with water, if we kindle fire in the grate D, the first portions of water heated, having become specifically lighter, will tend to rise : they will actually mount into the up- per part of the boiler, and, of course, enter the tube b f : at the same time an equivalentquantityof water will re-enter the boiler by the other extremity c of the tube. We perceive that these simultaneous movements will determine a circulation in the whole mass of the liquid, which will continue as long as heat is generated in the fire- place ; and if we suppose that the tubes, throughout their different windings, are applied against the walls of a chamber, or a stove-room, the air will get warmed by contact with the hot surfaces ; and we may accelerate the warming by multiplying these contacts in the mode indicated. "This calorifere cannot be employed so usefully as those with heated air, when It is wished to heat large apartments. In fact, the passage of heat ihrouirh metallic plates is in the ratio of the difference of temperatureandquantity of the heating surfaces. In the present case, the temperature of the water, without pressure, in the tubes, must be always under 100° C. (212° F.), even in those points where it is most heated, and less still in all the other points, while the temperature of the flues in air staves, heated directly by the products of combustion, may be greatly higher. In these stoves, also, the pipes ■;( Hi 'ih 4 340 CALICO PRINTING. block printing) ; the printing table, d, d ; and the feeding, drying, and colouring roUera,/,/ 5r,5r. A,^ ;> The machine is also provided with a carriage, t, i, for the printing blocks i ?i S^mSrSmi^g: '^"'^ " '^^^ ""' ^' ^"^'^'^^ ^^^^^ ^P-^ -^^ ^> rattlci'e'd t'c The operation of the machine is effected by passing a drivinffstran / rm,nH tv,» dnymg puUey m, fixed at the extremity of the main drifine shift ^ 7' At t^Pnt? wheel ;> which is mounted upon the end of the cross shaft q ; at about the middle of ?hovl^^^^ "^^'^ wheels rr, driving the upright shaft ,, , and mitre Xels" / tl'^^TTi^J.^'^l'''^:^!''^'^' "' ^' ^^^ feeding rollers/,/, and th^^^a^ Smmltaneously with the progress of the cloth, the mitre wheels r, v at the other lltltT^T^lT ^.' t^'^' '\f ^^^^^^K roUe;s «,, .., ,., by means'of the spur gea^ ^ng X, ^, X. The furnishing rollers, revolving in their respective color-boxes spread^ rltlr anVte"fSh?nl'?^f """ 'l^'r '^^"'^^^' ^^ ^ '^^ which pass round' hfto"^ roller ana the turnishmg tables or beds, c, c, c, in order to supply the colors to th^ ^""^f hrn^i.'*"'!? mJ'^^ ^^°-'^^' •''.' •^■' •^*- Either 'beds or the backs of the printing bloJk* SnnnnZt tS^ ^- ^^^^^^ic, to insure the perfect taking up of the colons. " the beds c^c it Td'rfwn'' •' '' ^' r ""; "P"" ^^^ ^^^^^^y«' ^^ t^^ f-^thest point froi. me beas c, c, it is drawn inward toward the furnishinff beds c c h\ means of tht spur.wheela:,upon the driving-shaft «, taking into a smk plL^^Xwu bf dot^^ m /g. 17), upon the shaft, 2. On the end of this shaft is also keyed t^e manele ?'hT\^^?f •"°^i" '^' "'""J^", ^^^^^' 4' ^^i<^^ i« keyed u,^n the end of the 7^1 leefil IdT"" «P^^-^h^^'> «^ i'^ gear with the pLion,^ made fast to the sh^',! Upon either end of the shaft, 5, is a rack pinion, 9, taking into the horizontal rack 10, made fast to the carnage-frame, t, i ; and thus the blocks j, j, are presented to the fur- nishing blankets y y, y, and take a supply of colour ready for printing. The traveUinc- carriage and blocks now retire, by the agency of the mangle-wheel and pinion, 3 and 4 the pmion being fixed upon the end of the shaft, 2, and the wheel upon the other shaft in a Ime with the shaft 2. At this time another operation of the machine takes placa. CALICO PRINTING. 341 Upon the reverse end of the shaft 6, is a pinion, 11, gearing with the spur-wheel 12; and by means of the spur gearing, 6 and 13, and counter-shaft> 14, the pinion 16, 317 drives the spur-wheel, 16, which corresponds to the wheel, 12, on the other side of the machine. To one of these spur-wheels are attached by bolts two quadrant levers, 17, 17 • and as these wheels revolve by means of the gearing just described, the levers, 17*, 17| draw down the chains, 18, 18, actuate i\xQ levers, 19 and 20, and thus elevate the whole eeries of printing blocks in the parallel groove^ 21, 21 ; at the same time pressing or closing them into one mass or block by expanding the springs, 22, 22; and at the nest of the carriage caused at a proper interval by the agency of the mangle-wheel, the blocks are made to impress the patterns upon the surface of the goods at once, in four <»i- more different colours, and in one, two, or more widths of cloth at one operation. The cloth is now drawn forward for the space of the exact width of one of the blocks, or sketch of the design, by means of the spur-wheels and pinions, 23, 28, and passed around heated cylinders, g g, if necessary, and between the delivering rollers out of the machine. These operations are to be repeated by the continuous rotation of the main ^^ When pyrof'gnite of ron alone is used, the dyes are not so rich as when some purer acetate of iron fadded to It ; to favour the niore ready oxidizement of the metal, which should be always intn^ duced into the stuff in the state of black oxide. The basic pyrophosphato of iron S ^Iv iVL S"- ' "'^^n i^"V° ^^'^"^^^ °^^^^^«*' especVall/with ammoniTwhicg may be dy^d immediately after mipression. When absolution of sulphate of i7on is mixed with one of pyrophosphate of soda, the whitish precipitate miy be dissoWed Tm crystals (chloretm) dissolved in the sulphuric acid of Nordhausen to saturation have at first the consistence of syrup, but become afterwards solid ; and being kept out' GenercUities of Calico FHnting.^l. Of the colours fixed in the humid way. or in the water-bath, and with concourse of mordants; the simple genera are derived from the apphcation of indigo, carthamu^ curcuma, catechu, and the oxides of iron and chr^e the peroxides of manganese, and lead ; with the sulphide of antimony ' 1. From indigo, there are the following species •— - (1.) The blue vat or blue ground ; such as pencil blue, china blue, blue of solid appU- eation. Indigo is reduced into a soluble stato by grinding in the ioist condition^and mixing 100 parts of it with from 75 to 95 parts of green lulphato of iron, and 100 of qmcklime, m the vat along with 8000 parts of water, and stirring vigorously from time to time The vat is best heated by transmitting stoam into it through pipes. X hi^ the mdigo vat may be prepared for action in the course of 12 houi^ Thefiq^d to time means should be transparent and of a fine yellow hue ; and should have a coppery looking pellicle on its surface. To insure complete oxidizement to the indigo in the substance of the stufl^ it may be padded through a weak solution of sulphate of copper, mixed with a little boiled starch and glue. See Indigo. Resist pastes for indigo may consist of solutions of the copper salts, which act on che- mical principles by furnishing oxygen to the indigo and thus rendering it insoluble and incapable of entering the fibres of the stuff; or they are composed of pipe clay, sulphate of lead, and such articles as act mechanically. A resist paste with sulphate of zinc and alum answers well for brief immersions in the vat, and it washes easily away. The arseniatos and phosphates are sometimes used along with the salts of copper to prevent the fixation of this metal reduced upon the cloth. The following are some receipts for reserve pastes. No. 1. For deep blues. In 9 quarts of water dissolve, 12 pounds of sulphate of copper 5 — acetate of copper 6 — nitrate of copper, at 16' B. 6 — gum arabic 2 — pipe clay ; the latter two being thickeners. Bfa 2. In 9 quarts of water dissolve, 8 pounds of sulphate of copper 4 6| 4 8 Ko. 3. For cravats. acetate of copper — nitrate of copper, at 55* B. thickened with — gum arabic — pipe clay In 9 quarts of water dissolve 8 pounds of sulphate of copper 4 — acetate of copper 4 — nitrate of copper, at 55* B., thickened with 4 — of gum arabic 8 — of pipe clay. In other formulie, a little alum is used ; in others, verdigris dissolved in vinegar is added to the mixture ; in some a little cream of tartar is introduced, also a very small quantity of sulphuric acid for handkerchiefs to be printed on both sides. In 9 quarts of water, 3 pounds of sulphate of copper, \ pound acetate, to be thickened with » pound of starch and 7 pounds of gum, 6^ pounds of pipe clay ; the whole being coloured with I pound of acetate of indigo. By another formula a resist paste is made by dissolving in 8 pints of water, 20 pounds of sulphate of zinc, incorporated with 4J pounds of pipe clay 5 li u 12 of soft soap of lard olive oil oil of turpentine of mucilage at 2 pounds per quart. All the above pastes should not be thicker than what is absolutely necessary, and the cloth to be printed should be highly calendered ; in printing with blocks the workmen should strike them with their hand and not with a mallet. It is advisable to dip the frame with its stretched piece of cloth in milk of lime before plunging it in the vat ; in which it should receive 4 or more immersions, with airing intervals for the oxidizement of the indigo. Pencil blue, as applied by hand. — ^To 35 P'^' ?^ '^' ^^^^^^ the Cloth 18 coiled, and which is turned bVmears of! h\n5 'o?^ ^^' reel rou^d which euper-saturated with lemon juice, passes ffororanifo?i'-i ^^}^!T'^ being slightly carthamine is ready to be iposiLd upoTthe c^nf^^^^ which have been sulphured, are to beCevx'^uslv n ^"^^/.^^^^^ i" the tub. Silk? brighter coloui-s are obtained upon cotton ^ ^""''"^ *^'^"^^ * ^^^ ^ath. But chi|;ta;^^^^^^^^^^ This drug is emploved Mnds of silk handkerchiefs with rmoTda tf iro'n'anf^^^^^ '^^ ^^^^^^ -^*- 77ie colours derived from annotto —To Hv^^LfT ^, ^^""^^^a- to be made of it, alon^ with a Xtion of /ex^^^^^^^^ J^f "?^^""^: ^° ^^^^^^'^^ <^-o<^tion is It needs no mordant, and affords an oranteWw a"" ^^Y"^ *^^ ^^^^^ ^« *<> ^e plunged, tralized by an acid bath. A solution of p^eroSo^^^^^^ t^'V^'' ^^^'"'^ ^"^ ^^^^ ^«"- . blue vat, produces very fine blacks. cTiloh.\Z ' ^l^ ^^''^' combined with the quarts of water, ^ pounds of Ta W w^^^^^^^ for dyeing by dissolving in 9 sal ammoniac, and 10 pounds of gumirlbt ^ ""^ ^'"^^^ ^^^^er, 2 pounds of has br ^^^^^^^^ th-e Pound^of catechu in fine powder, which heat, till It be reduced iy one tenth alow7e quarts of acetate of protoxide of iron at 1^ R In^ o ^°^ ^^'^ ^.'l"^*'*^ «^ the above 6 to 9 quarts of the above catechu preVraion 1*4 o^^^^^^^^^ ">' ^^^^^^ the acetate of iron may ^F ; atX^;^'^^^^^^^^^^^ -^y be extensively modified ; the nitrate, if the proportions of the other Xble mlf?r l! ' ? ^ '"^/^^^^^' «^ «^«^ ^Y anpetri^S^^^^^ copper, fo^ ^sxx^uirb--^ the colours of cate4u areCeby rtdereSe; ^'''^'"^ '^^ "^^^'^"'^^ ^-«t, »: df t atumid r^te^^^ ntftinrthe^t^^ ^^ ^^ °^^'""- ^^ -e colours are then fixed by steaming, or by^ m^^f l^l^r^^^^^^ boiled, 4i quarts of solution of caustTc soda Tt ^ 1^ I^^^nds of flour, and when it S proportion of catechu without changtg the ratios Xlf ^v- T ^' \ ^"''^''"g '^- stances^ stronger or fainter shades mlv be obtaiip!l K, f exist among the other sub- gino{s pr:;^^^^^^^^^^ o/e>o..-One of the ferru- by addi^ngfo lOquartsof SS about Jw^^^^ ItismlZ very slow degrees in a large vitriol bottle and btr"' '*! ""t'^^^ ^^ ^"'P^"*^ <>f ^^^n by a portion of ammonia is formed Six d A , ^ ^ ™"i""^ ^""^" «^ these ingredient Towards the conclusion the sSatemusf^^^^ "^"P^^*^ this compound ensue in the thickening liquoZ It is l^'^j^^^ «^«^^y> otherwise frothing wiU density of 56- to 57° I When cooled bd^^^^^^^^^^ ^^^^^ ^^"^r. andlasa It should always be diluted to a ^trenllTon^^^^^ To dye with this preparation it is to be diluted to fW • i^ ^' ^^^''''^ ^^'""S "sed. pad'i°« ^'^ the bottom of the case.^ ^ i^ALOMEh. (Chlorure de Mercure, Fr. ; Vermsstes Quecksilber, Germ) The mild protochloride of mercury. The manufacture of this substance upok the g^eit scale TLrt rft,ri;\'M' ^"^-V J^ ^^^"P^«* ^"^ "^^^^ IS thrown down, which cannot be removed by washing and wliich e-ives u novinna S^dlagerr '"' "^'^'^ '^^'"'' "^^ "^^' prescribed^ the a W^fo^uir ob^^! ^The second manner of manufacturing calomel is to grind very carefully 4 parts of corrosive sublimate (bichloride of mercury) with 3 paits of quicLlver^ing TlittL water or spirits to repress the noxious dust during the trituration. The mas! L then mtroduced into a glass globe, and sublimed at a temperature gradually rmW The ?rme\ "l^rf^n" -i^V^^^f "'^^^'^^i^^' ""^ ^«--*« '' int^the ploc lorid^r calomel The following formula, upon the same principle, was recommended to the chemical manufacturer in Brande's Journal, for July 1818 '— ^'''^'^^^^^e*! ^o lUe "Prepare an oxysulphate of mercury, by boiling 25 'pounds of mercury with 35 pounds of sulphuric acid to dryness. Triturate 31 pounds of this dry salt With 20 poEnds 4 Zx^Tlj^Cr^'r^l^' ^^"^.^^^^ ^^TP^^^' ^"^ *^^" -^^ 17 pounds of^ommon 5^ an7i« 5 '' ^ ^^ thoroughly mixe<( and sublimed in earthen vessels. Betv^en fn the usua^w^?" '?^'' calomel are thus produced: it is to be washed andlevTglteS n™inKof ^ ^' ;, ^^ ^^^^^ '^ *^* P^^^^"^ "^e*^ ^t Apothecaries' Hall, London. The oxysulphate is made in an iron pot; and the sublimat'ion is performed in earthen veL- iW Jv"2t^^''''y^T^ "' '^^' of calomel should be separated from the accompany- iofivrs^bCate.' "" ""'"'''^ ^^' ^^^'"^ '^^ consists of mercury mixed with co^- n^fj! 'Tk 'T ™«^^fi?^*^«n «f the latter process, for which a patent, now expired, was TurfacP of Z.f ■ "^'T •' T'''' ^" conducting the sublimed vapou,^' over an^extS r?o^ artiol ?n I "?"*^7^\^,^ ^ ««^/rete^ct\ubn^^^^^^^^^^^ ^""^^-'''^ r'' f^'}. '' '^'7 '' ''^' P--"-« -''^e present 10 detect subnitrate of mercury in calomel, digest «^ i« a steam-cased pan. constitut^l ^hf ^ considerable tmie, the membraneous matters collect at the surface eonstituting the crflrc/f/t«g« used sometimes for feeding dogs, after the fat has been coprertrru 1 -Y' rf^^--. J^^'^"^' ^^^^^ ^^ ^'^^^^^ '^-»^^ - sieve iLTnother S^a whHp whin t>, r f "^"^ T'^^^' ^^ * ^*^^"§^ temperature in order to wash it. Af- ^meTnfnV t 1^ ^°'k ""f '^' ^.^' '^^'^"^ ^° *^^ ^«^--^^» t^e P«"fied tallow is lifted out, rea?y for use. '^ "^'^ ^"'^"*'' ^'^ '"^^ ^^ ^ °^°^^^^te size, where it concretes, and h tolln^A^Zri^^^l^ circumstance, that the wicks for the best candles are still cotton cotto? J?^- • .K^"" ^"'^'^'' Jjotwithstanding the vast extension and perfection of warS cut bv alTlu '^^ T^^ "^ T""! °^ ^' ^""" ^"^^ ^««°^« «^ <^^e^«> ^"^ after- made M.^ ^nS IT^""". '"*° ^'""^^' corresponding to those of the candles to be St .*/ ^^,!^^ank obtained a patent, in June, 1822, for a machine for cutting, twist- geLal u rth^ ""''^'^ ^'^'^' '^""/^ convenient, does not seem to have comnnto n«rot,?c " 1 ^5 OP^'^^'*""^ """"^ performed upon a series of threads at once. The ap- t^C 'L'il't- f ^ ^"' '^ ^^°"i."^ "''^^ ^^^ «P^^^^«^ «'»«• A reel extends acroS frnm .f • ^f, *'»"^^'' P^^t, Hpon which the cotton threads have been previously wound • St.- t; 'p^ ^v'^' ^^ 1'^^^^ ^^^° P'-^P^r ^^"?»^^' 'lo^^l^d' «"d cut by an ingeniouTme: of thnand/nnS^;.lf ^^-^ ""11^ ^^;^ the melted tallow, rubbing them between the palms tuhf ^w ' ""* allowing the taUow which adheres to harden, they may be arranged n7shed'w1,?.T", '^1- ^''^f'' ^'l '^' P^^P^^*' «^ ^'PP'^g- The dipping-room ?sf^. mshed with a boi er for melting the tallow, the dipping-mould, or cistern! and a large Thtnl/h' ^"PP^^-^^"& the broaches. From the ceiling of the workshop a long balance! theTroach'e'^ withT^'- 'i'" ""^ ""^. "^ ""^^^ ^ ^^^'^ ^^^"^^ ^^ ^"ached for holding «ie broaches with the wicks arranged at proper distances. The opposite arm is loaded t^ n .L''^ ' '^•'^""r"?^^^"'^ '^^ ^'«°^^^ ^'^'^ ^"d to enable the workman to asce^ nZ'? • P'^'Pr' ''f ' f ^^' '^"^^^- The end of the lever which supports the frame i» bv a iT'^'"'"^^ '^ri'^' dipping-cistern ; and the whole machine is so balanced that Is may be re'^red^ ' *^^ '''*'^' ^'^ ^^' '^'''^" '''^'' *^^ ""^^^^^ ^^^^'^'^ ^' ^^" bnS.^ ^"Uowing convenient apparatus for dipping candles has been long in use at Edin wlih fnJ" • ^^"^'^ ""^ *^^ dipping-room a strong upright post a a, fg. 320, is erected Stance. frL''nl^''''h ^' ^'' '^° .^"^^- ^''^^ ''' middle, six mortise! are cut at smSi mnvii f ™ one another, mto each of which is inserted a Ion- bar of wood b b, which whole ml'S^ih"^*"" '''' '"'" Pj"' ^^'•^ P^^^'"- ^^r«"§^ t^e "^^'J'^'e of the shaft. The wnoie piesents the appearance of a large horizontal wheel with twelve arms. A complete 21Z A 7"" f '^"^ """"^ '' ^!^^^ ^^ *^^ fig"^^- ^ro°^ the extremity of each arm is suspended a frame, or port, as the workmen call it, containing 6 rods, on each of which are hung 18 wicks, making the whole number of wicks upon the wheel 1296 The machine, though apparently heavy, turns round by the smallest effort of the workman • and each port, as it comes lu succession over the dipping-mould, is gently pressed down' wards, by which means the wicks are regularly immeFsed in melted taflow. As ^e ^Zh! •?' T- ^'' n" f II'' '"°-n ^'1f^'' ""^'^ "^ «^^'h '' loaded with nearly the same weight, It IS obvious that they will all naturally assume a horizontal position. lu order, however, to prevent any oscillation of the machine in turning round, the evers are kept in a l.orizontal position by means of small chains a a, one ind of which 18 fixed to the top of the upright shaft, and the other terminates in a small square piece of wood, 6, which exactly fills the notch c in the lever. As one end of the feve? must be depressed at each dip, the square piece of wood is thrown out of the not<;h CANDLES. d5S by the workmen pressing down the handle d, which communicates with the small lever <; inserted into a groove in the bar b. In order that the 8(^uare piece of wood fixed in one extremity of the chain may recover its position upon the workman's raising the port, a small cord is attached to it, which passes over a pulley in- serted in a groove near c, and com- municates with another pulley and weight, which draws it forward to the notch. In this way the operation of dipping may be conducted by a single workman with perfect ease and regularity, and even dispatch. No time is lost, and no unnecessary labour expended, in removing the ports after each dip ; and, besides, the process of cooling is much accele- rated by the candles being kept in constant motion through the air. The number of revolutions which the wheel must make, in order to complete one operation, must obviously depend upon the state of the weather and the size of the candles ; but it is said that, in moderately cold weather, not more than two hours are necessary for a single person to finish one wheel of candles of a common size. Upon the supposition, therefore, that six wheels are completed in one day, no less a number than 7776 candles will be manufactured in that space of time by one workman. I shall next describe the process of moulding, which, if possible, is even less com plicated in its details than that of dipping. The moulds are made of some metallic substance, usually pewter, and consist of two parts. The shaft or great body of the mould is a hollow cylinder, finely polished in the inside, and open at both extremities. The top of the mould is a small metallic cup, having a moulding within-side, and a hole to admit the wick. The two parts are soldered together, and when united, as will rea- dily be imagined, have the shape of a moulded candle. A third piece, called the foot, is sometimes added : it is a kind of small funnel, through which the liquid tallow runs into the mould, and, being screwed to the opposite extremity of the shaft, is removeable at pleasure. This additional piece may certainly be useful in very mild weather, since, by removing it, the candles may be drawn more easily from the moulds ; but, in general, it may be dispensed with. Eight or twelve of these moulds, according to their size, are fixed in a frame, which bears a great resemblance to a wooden stool, the upper surface of which forms a kind of trough. The top of the moulds points downwards, and the other extremity, which is open, is inserted into the bottom trough or top of the stool, and made quite level with its upper surface. In order to introduce the wicks into the mould, the workman lays the frame upon its side on an adjoining table, and holding in his left hand a quantity of wicks, previously cut to the proper length, he introduces into the mould a long wire with a hooked point. As soon as the hook of the wire appears through the hole in the top of the mould, he attaches to it the looped end of the wick, and, immediately drawing back the wire, carries the wick along with it. In this manner each mould in succession is furnished with a wick. Another workman now follows, and passes a small wire through the loop of each wick. This wire is obviously intended to keep the wick stretched, and to prevent it from falling back into the mould upon the frame being placed in the propel position for filling. The frame is th'^n handed to the person that fills the moulds, who previously arranges the small wires in such a manner that each wick may be exactly in the axis of the mould. The moulds are filled by running tallow into each of them, or into the trough, from a cistern furnished with a cock, and which is regularh' supplied with tallow of the proper temperature from an adjoining boiler. When the workman observes that the moulds are nearlyhalf filled he turns the cock.and laying hold of that portion of the wick which hangs out of the moulds, pulls it tight, and thus prevents any curling of the wick, which might injure the candles : he then opens the cock, and completes the process of filling. The frame is now set aside to cool ; and when the tallow has acquired a proper consistence, which the workman easily discovers by a snapping noise emitted by the candles upon pressing hi* thumb against the bottom of the moulds, he first withdraws the small wires which kepi the wicks tense, and then, scraping off the loose tallow from the top of the frame with \ small wooden spade, he introduces a bodkin into the loop of the wick, and thus Vol. L 2Z 354 CANDLES. CANDLES. 855 If m !!!>' i ! draws each candle in succession from its mould. The candles are now laid upon a table for the inspection of the exciseman, and afterwards removed to the storehouse. Previous to storing them up, some candle-makers bleach their candles, by exposing them to the air and dfcws for several days. This additional labour can be necessary only when the dealer is obliged to have early sales ; for if the candles are kept for some months, as they ought to be, before they are brought to market, they become sufficiently whitened by age. Wax candles.— Nejit to tallow, the substance most employed in the manufacture of candles is wax. Wax candles are made either by the hand or with a ladle. In the former case, the wax, being kept soft in hot water, is applied bit by bit to the wick, which is hung from a hook in the wall ; in the latter, the wicks are hunjr round an iron circle, placed immediately over a large copper-tinned basin full of melted wax, which is poured upon their tops, one after another, by means of a large ladle. When the candles have by either process acquired the proper size, they are laken from the hooks, and rolled upon a table, usually of wabiut-tree, with a long square instrument of box, smooth at the bottom. A few years ajjo I made a set of experiments upon the relative intensities of light, and duration of different candles, the results of which are contained in the followine table. Namber in a pound. Duration of a candle. Weight in grains. Consumption per hoar in grains. Proportion of ight. Eronomy of light. Candlcfc equal one Argand. 10 mould - - - 10 dipped- - - 8 mould - - - 6 ditto - - - 4 ditto - - - Argand oil flame k. m. 6 9 4 36 6 31 7 2| 9 3-6 682 672 856 1160 1707 132 150 132 163 186 512 12i 13 101 14f 20i 69-4 68 65^ 69| 66 80 100 5-7 5-25 6-6 5-0 3-5 A Scotch mutchkin, or | of a gallon of good seal oil, weighs 6010 gr., or 13 JL oz., avoirdupois, and lasts in a bright Argand lamp 11 hours 44 minutes. The weight of oil it consumes per ho'ir is equal to 4 times the weight of tallow in candles 8 to the pound, and i the weigh of tallow in candles 6 to the pound. But, its light being equal to that of 6 of the latter candles, it appears from the above table that 2 pounds weight of oil, value 9d. in an Argand, are equivalent in illuminating power to 3 pounds of tallow candles, which cost about two shilhngs. The larger the flame in the above candles the greater the economy of light. In June, 1825, M. Gay Lussac obtained a patent in England for making candles from margaric and stearic acidsy improperly called */eanw«, by converting tallow into the above fat acids by the following process : — Tallow consists, by Chevreul's researches, of stearine, a solid fat, and elaine, a liquid fat; the former being in much the larger proportion. When tallow is treated with an alkaline body, such as potash, scda, or lime, it is saponified j that is, its stearine and elaine become respectively stearic and elaic acids, and, as such, form compounds with these bases. When by the action of an acid, snch as the sulphuric or muriatic, these combinations are decomposed, the fats reappear in the altered form of •tearic and elaic acids ; the former body being harder than tallow, and of a texture somewhat like spermaceti, the latter body being fluid, like oil. " The decomposition of the soap should be made," says the patentee, "in a large quantity of water, kept well stirred during the operation, and warmed by steam introduced in any convenient way. When the mixture has been allowed to stand, the acid of the tallow or fat will rise to the surface, and the water being drawn off will carry the alkaline or saline matters with it, hut if the acids of the tallow should retain any portion of the salts, fresh water may be thrown upon it, and the whole well agitated, until the acids have become perfectly free from the alkaline matters ; and when allowed to cool, the acids will be formed into a solid mass. This mass is now to be submitted to considerable pressure in such an api)a- ratus as is employed in expressing oil from seeds ; when the liquid acid will run off in the form of a substance resembling oil, leaving a solid matter, similar, in every respect, to spermaceti, which is fit for making candles." The wick to be used in the manufacture of these improved candles, and which forms one of the features of this invention, is to be made of cotton yarn, twisted rather hard, and laid in the same manner as wire is sometimes coiled round bass strings of musical instruments. For this purpose straight rods or wires are to be procured, of suitable lengths and diameters, according to the intended size of the candles about to be made : and these wires, having been covered with cotton coiled round them as described, lire to be inserted in the candle moulds as the common wicks are ; and when the candle is made, and perfectly hard, the wire is to be withdrawn, leaving a hollow (jylindrical aperture entirely through the middle of the candle. See Stkarink. CANDLES. Messrs. Hempel and Blundell have given a very minute account of the process for making pahn-oil, stearic and margaric acids, in the specification of their patent for this mode of manufacturing candles : — 1. Their first process is called crystallization, which consists in pouring the melted palm-oil into iron pans, and allowing it to cool slowly, whereby, at about 75° F., the elaine separates from the crystalline stearine and margarine. 2. The concreted oil is subjected to the action of an hydraulic press, in order to sep- arate the elaine from the solid fats. 3. This process is called oxidation. To 104 lbs. of the stearine and margarine, melted in an iron pan, about 12 lbs. of slaked and sifted quicklime are added, with diligent stirring, during which the temperature is to be slowly raised to 240" F., and 6o maintained for about three hours, till a perfect chemical combination takes place. This is shown by the mass becoming thin, transparent, and assuming a glassy appear- ance when it cools. The fire being now withdrawn, cold water is added very gradually at first, with brisk stirring till the whole mass falls into a state of powdery granulation, when it is passed through a wire sieve to break down any lumps that may remain. 4. Separation of the stearic and margaric adds from the lime. For this p'^rpose, as much muriate of lime (chlorcalcium) is taken as will, with its equivalent qi:>t,itity of sulphuric acid (8 lbs. of dry chlorcalcium require 7 lbs. of the strongest sulphuric acid), produce as much muriatic acid as will dissolve the lime combined with the fat acids ; and therefore that quantity of muriate of lime dissolved in water must be treated with as much sulphuric acid as will saturate its lime and throw it down in the state of sulphate of lime. Add the supernatant solution of muriatic acid in such pro- portion to the stearate and margarate of lime as will rather more than saturate the lime. Three pounds of muriatic acid diluted with 9 lbs. of water are stated as enough for 1 lb. of lime. This mixture is to be let alone for 3 or 4 days, in order to insure the complete separation of the lime from the fat acids ; and then the mixture is heated so as to melt and cause them to separate in a stratum on the top of the liquid. The re- sulting muriate of lime is drawn off into another tub, and decomposed by its dose of sulphuric acid, so as to liberate its muriatic acid for a fresh operation. 5. The fat acids, being well washed by agitation with hot water, are then set to cool and crystallize, in which state they are subjected to the action of the hydraulic press, at a temperature of 75" F., whereat the margaric acid runs off from the solid stearic acid. 6. Bleaching. The stearic acid is taken from the press, and exposed upon water in large shallow vessels placed in the open air, where it is kept at the melting tempera- ture from 8 to 12 hours, stirring meanwhile, in order to promote the blanching action of the atmosphere. The margaric acid is bleached in a similar manner in separate vessels. 7. Refining process. The fat is warmed again, and poured in a liquid state into an agitating tub ; where, for every 1,000 lbs. of the stearic acid, about 2| lbs. of common black oxide of manganese, and 40 lbs. of concentrated sulphuric acid, diluted with 200 lbs. of pure water, are to be used. This solution (" mixture"), while warm from the heat evolved in diluting the acid, is placed in a suitable vessel above the agitating tub. The stearic acid being at the melting point, in the vessel below, agitation is to be given with a revolving shaft, while the mixed manganese and acid are run slowly down into it, till the whole be well mixed, which generally requires about two hours. Th': mass b allowed to lie in this state for 48 hours ; after which it may be boiled by ■lean for 2 or 3 hours, when it will be sufficiently refined. The sulphuric acid, which is at the bottom, is now run off, and the stearic acid which remains is well washed with pure water. It is then put into large conical vessels of stoneware, enclosed in a box or jacket, kept warm by steam-heat, and lined with conical bags of suitable strong filtering paper, through which, being warm, it finds its way ; and when the stearic acid has bei^n tjjus filtered, it is run into blocks, when it will be found to be a beautiful itearic acid or palm-wax, and is ready to be made into candles in the usual way. On the above process with manganese and diluted sulphuric acid, it may be observed, that no solution or chemical action takes place between them, and their joint use seems therefore most problematical. The patentees proceed to describe other processes of refining, in which sulphate of manganese, with common salt, phosphoric acid (highly concentrated), and oxalic acid, are used, and in my opinion either ignorantly or for the purpose of mystification ; for, as prescribed, they can serve no possible purpose of purifying the stearnine. The chief solid constituent of palm-oil is margaric acid. This they direct to be melted with tallow, in the proportion of from 10 to 20 lbs. of the former to 100 lbs. of the latter. See NevotorCs Journal, C. 8., xL 207. 222* 856 CANDLES. if! I was told by M. Runge, at Berlin, that lie was the inventor of the process for makini^ white margaric acid from palm-oil, and that Hempel h&d got it somehow irom him, but most imperfectly, as it would appear. Hempel died here in the midst oi tne above patent operations; but the specification is, no doubt, a specimen of his "" m" WM ''^ of Runge's margaric acid He gave me a splendid pearly-looking sample. Mr. Wilson of Belmont, Vauxhall, obtained in August, 1844, a patent for Tmprove- menta m treating fats for inaking candles. If distilled fats are used in making compo- site candles, they are bleached and hardened in that operation. When palm5>il is the material, it is first sapomfied ; then distilled, granulated by fusion and slow cooling and cold-pressed ; by which means stearic acid and a light coloured oil are obtained • which may be mixed with the steanne of cocoa-nut oU, or other stearine. A cheaper' article Tl A^A^ ^J ""J?"^ the entire product of the above distillation with half its weight of distilled and cold-pressed stearic acid of tallow. Tallow is deprived of its oleine bv pressure accompanied by artificial cold if necessary ; this being added to the other harS matter the mixture is converted mto fatty acids, and distilled, and the entire product of d^tillation IS employed for makmg candles ; or it may be pressed to make them harder. Aa distilled stearic acid is more crystalline than undistillei 2 or 4 per cent, of wax may be added to assist the combmation of the fatty acid with the Bte&nne.—Newto7i'8 Jour- nal, XXVI. 165. Candles consisting of alternate layers of tallow and stearine have been made by dippinff their wicks alternately m these two fatty bodies in a fluid state. Mr. W. iSykes has gone to the expense of a patent on the contrivance. The wicks are impregnated with a solution of bismuth or borax. ^ New patent candle manufacture.— YegetaUe tallow melts at a degree of heat somewhat above that of animal tallow, but considerably below that of vegetable wax. Mr. Wilson of Belmont, Vauxhall, treats his tallow by putting 6 tons of it into an iron still capable of ho ding 9 tons, heats it gradually to 350° Fahr., and then adds gradually 1440 lbs of sulphuric acid of 1-8 sp. gr. At the expiration of about 2 hours, the tallow is pumped into a vessel, containing water slightly acidulated with sulphuric .\-id • and is therein agitated by free steam passing through it for 2 hours. The materials are then left to repose for 6 hours ; both this vessel and the former should be provided with a cover and a means of conveying the gases which may be evolved into a chimney. Ihe vegetable tallow is next distilled in such a manner that the atmosphere is excluded This is best effected by the use of steam highlj heated, which he introduces into the stilL m numerous jets below the tallow. The distilled products are received into condensers and they may be used alone, or they may be mixed with other matters for making the best class of candles. The patentee improves paraffine by a like process. He makes candles with 2 or 3 wicks, by mixing palm-oil pressed with tallow, or the above distilled fat, for burning in cundle lamps. — Newton's Journal, xxxv. 108. The following is one of his later processes. Candles and night-lights are manufactured by 3Ir. Wilson of Vauxhall, by combining palm-oil which has been bleached by the atmosphere with distilled fatty acids, with or without other fats. By combining one part of crude cocoa-nut oil, one part of cold pressed atmospherically bleached palm-oil and one part of impressed palm-oil, acidified by sulphuric acid and distilled, an excellent product 18 obtained ; and other distilled fatty acids may be used, pressed or unpressei fhis distillation is effected by transmitting through the fat contained in an iron stilL steam at about 600° or 700° Fahr., heated by passing through iron pipes laid in a fire. The steam is transmitted till the oily matter is heated to about 350° ; the vapours produced being carried into a high shaft by a pipe from the cover of the iron vessel. The hot oily matter is then run into another vessel made of brick lined with lead, and sunk in the ground, for the purpose of supporting the brick-work under or against the internal pressure of the fluid. It has a wooden cover lined with lead, directly beneath which, and extending across the vessel, is a leaden pipe, 1 inch in diameter, having a small hole in each side, at every six inches of its length ; and through this pipe is introduced a mixture of 1000 lbs. of sulphuric acid, sp. gr. 1 -8., and the same weight of water. The introduc- tion of the mixture which falls in divided jets into the heated fat, produces violent ebul- lition ; and by this means the acid and fat are perfectly incorporated before the action of the acid becomes apparent by any considerable discoloration of the fat. As the ebulli- tion ceasesj the fat gradually blackens ; and the matter is allowed to remain for 6 hours after the violent ebullition has ceased. The offensive fumes produced are carried off by a large pipe, which rises from the top of the vessel, then descends, and afterwards rises again into a high chimney. At the downward part of this pipe a small jet of water is kept playing, to condense such parts of the vapours as are condensable. At the end of the 6 hours above mentioned, the operation is complete, and the product is then pumped into another close vessel and washed by being boiled up (by means of free steam) with half its bulk of water. The water is drained off, and the washing repeated, except thai in the second washing the water is acidulated with 100 lbs. of sulphuric acid. The CAOUTCHOUC. 357 ultimate product is allowed to settle for 24 hours ; after which it b distilled in an atmo- sphere of steam, once or oftener, until well purified ; and the product of distillation is again washed, and after being pressed in the solid state, is applied to ihe manufacture of candles. — Newton's London Journal, xxvi. and xxxv. CANE-MILL. See Mill and Sugar. CANNON. For the composition of these implements of destruction, see Bronze. CANVASS. {Canevas, Fr. ; Segeltuch, Germ.) It has been found that sails of ships Hade with the selvages and seams of the canvass running down parallel to their edges, ye very apt to bag, and become torn in the middle, from the strain to which they are sub- jected by the pressure of the wind. To obviate this inconvenience, a mode of making sails, with the seams and selvages running diagonally, was proposed by Admiral Brooking, ind a patent granted to him for the same on the 4lh of September, 1828. The invention of Messrs. Ramsay and Orr, which we are about to describe, has a similar object, viz., that of giving additional strength to sails by a peculiar manner of weaving the canvas* of which they are made. The improvement proposed under their patent of March, 1830, consists in weaving the canvass with diagonal threads; that is, placing the weft yam, or shoot, in weaving, at an oblique angle to the warp yarns, instead of making the decussation of the warp, or weft threads, or yarns, at right angles to each other, as in the ordinary mode of weaving. To accomplish this object, the loom must be peculiarly constructed ; that is, its warp and work beams must stand at an oblique angle with the sides of the loom, and the batten and slay must be hung in a peculiar manner, in order to beat up the weft, or shoot, in lines ranging diagonally with the warp. No drawing is shown of the method by which this arrangement of the loom is to be made, but it is presumed that any weaver would know how to accomplish it : the invention consisting solely in producing sail-cloth with the threads or yarns of the weft ranging diagonally at any desired angle with the direc tion of the warp thread. CAOUTCHOUC, GUM-ELASTIC, or INDIAN-RUBBER {Federharz, Germ.), oc- curs as a milky juice in several plants, such as the siphonia cahuca, called also hevea guir anensiSf cautschuc, jatropha elastica, caatilleja elaslica, cecropia pdlatay ficus religiosa and undicay urceolaria elastica, &c. It is, however, extracted chiefly from the first plant, which grows in South America and Java. The tree has incisions made into it through the bark in many places, and it discharges the milky juice, which is spread upon clay moulds, and dried in the sun, or with the smoke of a fire, which blackens it. The juice itself has been of late years imported. It is of a pale yellow color, and has the consistence of cream. It becomes covered, in the bottles containing it, with a pellicle of concrete caoutchouc. Its spec. grav. is 1-012. When it is dried, it loses 55 per cent, of its weight : the residuary 45 is elastic gum. When the juice is heated, it immediately coagulates, in virtue of its albumen, and the elastic gum rises to the surface. It mixei with water in any proportion ; and, when thus diluted, it coagulates with heat and alco- hol as before. The specific gravity of caoutchouc is 0-925, and it is not permanently increased by any degree of pressure. By cold or long quiescence, it becomes hard and stiff. When the milky juice has become once coherent, no means hitherto known can restore it to the emulsive state. By long boiliug in water it softens, swells, and becomes more readily soluble in its peculiar menst/ua ; but when exposed to the air, it speedily resumes its pristine consistence and volune. It is quite insoluble in alcohol ; but in ether, de- prived of alcohol by washing wiih water, it readily dissolves, and affords a colorless solution. When the ether is evaporated, the caoutchouc becomes again solid, but is somewhat clammy for a while. When treated with hot naphtha, distilled from native petroleum, or from coal tar, it swells to 30 times its former bulk ; and if then triturated with a pestle, and pressed through a sieve, it affords a homogeneous varnish, which being applied by a flat edge of metal or wood to cloth, prepares it for forming the patent water-proof cloth of Mackintosh. Two surfaces of cloth, to which several coals of the above varnish have been applied, are, when partially dried, brought evenly in contact, and then passed between rollers., in order to condense and smooth them together. This double cloth is afterwards suspended in a stove-room to dry, and to discharge the disagreeable odour of the naphtha. Caoutchouc dissolves in the fixed oils, such as linseed oil, but the varnish has not the property of becoming concrete upon exposure to air. It has been lately asserted that caoutchouc is soluble in the oils of lavender and sas- safras. It melts at 248° R, and stands afterwards a much higher heat without undergoing any further change. When the melted caoutchouc is exposed to the air, it becomes hard on the surface in the course of a year. When kindled it burns with a bright flame and a great deal of smoke. Neither chlorine, sulphurous acid gas, muriatic acid gas, ammonia, nor fluosilicic acid 358 CAOUTCHOUC. CAOUTCHOUC. 359 it ! \ gas affects it, whence it forms very valuable flexible tubes for pneumatic chemistry. Cold sulphuric acid does not readily decompose it, nor does nitric acid, unless it be somewhat strong. The strongest caustic potash ley does not dissolve it even at a boiling heat. Caoutchouc, according to my experiments, which have been confirmed by those of Mr. Faraday, contains no oxygen, as almost all other solid vegetable products do, but is a mere compound of carbon and hydrogen, in the proportion, by my results, of 90 carbon to 10 hydrogen, being three atoms of the former to two of the latter. Mr. Faraday ob- tained only 87-2 carbon, from which I would infer that some of the carbon, which in this substance is difficult to acidify by peroxyde of copper, had escaped its action. It is ob- vious that too little carbonic acid gas may be obtained, but certainly not more than cor- responds 10 the carbon in the body. No carbon can be created in the process of ultimate analysis by pure peroxyde of copper such as I employed ; and I repeated the ignition after attrition of the mixture used in the experiment. Melted caoutchouc forms a very excellent chemical lute, as it adheres very readily to glass vessels, and withstands the corrosive action of acid vapors. This substance is much used for effacing the traces of plumbago pencils, whence it derived the name of Indian-rubber. It has been lately employed very extensively for making elastic bands or braces. The caoutchouc bottles are skilfully cut into long spiral slips, which are stretched, and kept extended till nearly deprived of their elasticity, and till they form a thread of moderate fineness. This thread is put into a braid machine, and covered with a sheath of cotton, silk, linen, or worsted. The clothed caoutchouc is then laid as warp in a loom, and woven into an elegant riband. When woven, it is exposed upon a table to the action of a hot smoothing iron, which re- storing to the caoutchouc all its primitive elasticity, the riband retracts considerably in length, and the braiding corrugates equally upon the caoutchouc cores. Such bands pos- sess a remarkable elasticity, combined with any desired degree of softness. Sometimes cloth is made of these braided strands of caoutchouc used both as warp and as weft, which is therefore elastic in all directions. When a light fabric is required, the strands of caout- chouc, either naked or braided, are alternated with common warp yarns. For this mixed fabric a patent has been obtained. The original manufacturer of these elastic webs is a major in the Austrian service, who has erected a great factory for them at St. Denys, near Paris. See Elastic Bands. Mr. William Henry Barnard, in the course of some experiments upon the impregnation of ropes with caoutchouc, at the factory of Messrs. Enderby, at Greenwich, discovered that when this substance was exposed to a heat of about 600° F. it resolved itself into a vapor, which, by proper refrigeratory methods, was condensable into a liquid possessing very remarkable properties, to which the name caoutchoucine has been given. For this invention "of a solvent not hitherto used in the arts" Mr. Barnard obtained a patent, in August, 1833. His process for preparing it is described in his specification as follows: — I take a mass of the said caoutchouc, or Indian rubber, as imported, and having cut it into small lumps, containing about two cubic inches each (which I prefer), I throw these lumps into a cast-iron still (which I find adapted for the purpose, and a diagram of which is annexed to, and forms part of, this my specifi- cation), with a woim attached; fig. 321, a is the still, b the cover ground to a metallie fit, to admit of a thermometer to take the temperature ; o the fire-place, d the ash-pit, s the worm-tub and worm, f the brick-work of the still, g a roller and carriage, in con- junction with a crane, or other means, to raise the cover to take out the residue, and to charge the same ; h the chain. " I then apply heat to the still in the usual manner, which heat is increased until the thermometer ranges at 600 degrees of Fahrenheit, or thereabouts. And, as the ther mometer ranges progressively Uf)ward8 to 600 degrees of Fahrenheit, a dark-coloured oil or liquid is distilled over, which I claim as my said invention, such liquid being a solvent of caoutchouc, and other resinous and oleaginous substances. When the ther mometer reaches 600 degrees, or thereabouts, nothing is left in the still but dirt and charcoal. I have found the operation of distillation to be facilitated by the addition of a portion •f this oil, either previous or subsequent to rectification, as hereinafter mentioned, in the proportion of one third of oil to two thirds of caoutchouc. I afterwards subject the dark-colored liquid thus distilled to the ordinary process of rectification, and thereby obtain fluids varying in specific gravity, of which the lightest hitherto has not been under 670, taking distilled water at 1000, which fluids I also claim as my said invention. At each rectification the color of the liquid becomes more bright and transparent, until, at the specific gravity of 680, or thereabouts, it is colorless and highly volatile. In the process of rectification (for the purpose of obtaining a larger product of the oil colorless) I put about one third of water into the still. In each and every state the liquid is a solvent of caoutchouc, and several resinous and oleaginous substances, md also of other substances (such as copal), in combination with very strong alcohol. Having experienced much diflUculty in removing the dirt which adheres to the bottom of the still, I throw into the still lead and tin in a state of alloy (commonly called solder), to the depth of about half an inch, and, as this becomes fused, the dirt which lies on the surface of it is more easily removed. Objections have been made to the smell of this liquid : I have found such smell re- moved by mixing and shaking up the liquid with nitro-muriatic acid, or chlorine, in the proportion of a quarter of a pint of the acid (of the usual commercial strength) to a gallon of the liquid. The discovery of the chemical solvent, which forms the subject of the patent above described, has excited considerable interest in the philosophic world, not only from its probable usefulness as a new article of commerce, but also from two very extraordinary characteristics which it is found to possess, viz., that, in a liquid state, it has less specific gravity than any other liquid known to chemists, being considerably lighter than sul- phuric ether, and, in a state of vapor, is heavier than the most ponderous of the gases. Its elementBTy constituents are, Carbon 6*812 - - -8 proportions. Hydrogen ... - 1-000 - - - 7 ditto. This new material (when mixed with alcohol) is a solvent of all the resins, and particu- larly of copal, which it dissolves, without artificial heat, at the ordinary temperature of the atmosphere ; a property possessed by no other solvent known ; and hence it is pecu- liarly useful for making varnishes in general. It also mixes readily with oils, and will be found to be a valuable and cheap menstruum for liquefying oil-paints ; and, without in the slightest degree affecting the most delicate colors, will, from its ready evaporation, cause the paint to dry almost instantly. Cocoa-nut oil, at the common temperature of the atmosphere, always assumes a con- crete form ; but a portion of this caoutchoucine mixed with it will cause the oil to become fluid, and to retain sufficient fluidity to burn in a common lamp with extraordinary brilliancy. Caoutchoucine is extremely volatile ; and yet its vapor is so exceedingly heavy, tltat it may be poured, without the liquor, from one vessel into another like water. Hitherto the greater part of the caoutchouc has been imported into Europe from South America, and the best from Para ; but of late years a considerable quantity has been brought from Java, Penang, Sincapore, and Assam. About twelve years ago, Mr. William Griffith published an interesting report upon the Ficus elcutiea, the caoutchouc tree of Assam, which he drew up at the request of Captain Jenkins, agent in that country to the Governor-General of India. This remarkable species of fig-tree is either solitary, or in twofold or threefold groups. It is larger and more umbrageous than any of the other trees in the extensive forest where it abounds, and may be distinguished from the other trees, at a distance of several miles, by the picturesque appearance produced by its dense, huge, and lofty crown. The main trunk of one was carefully measured, and was found to have a circumference of no less than 74 feet ; while the girth of the main trunk along with the supports immediately round it, was 120 feet The area covered by the expanded branches had a circum- ference of 610 feet The height of the central tree was 100 feet It has been estimated, after an accurate survey, that there are 43,240 such noble ciees within a length of 30 miles, and breadth of 8 miles of forest near Ferozepoor, in the district of Chardwar, in AssauL Lieutenant Veitch has since discovered that the Ficus elastica is equally abundant in the district of Naudwar. Its geographical range in Assam seems to be between 25 deg. 10 min. and 27 deg, 20 min. of north latitude, and between 90 deg. 40 min. and 96 deg. 30 min. of east longitude. It occurs on the slopes of the hills, up to an eleva- tion of probably 22,600 feet This tree is of the banyan tribe, famed for its pillared .160 CAOUTCHOUC. CAOUTCHOUC. ' 361 m i i \v M \i\ 1 i H ji l! i m I shade, whose daughters grow about the mother tree," which has furnished the motu tot rami quot arhores, to the Royal Asiatic Society. Species of this genus afford crate^ luisnade, however, in the tropical regions of America, as well as Asia Many species of other trees yield a milky tenacious juice, of which birdlime has r-5!L""^^?" ^ ^^1^' 5' ^^^'^f^r/'n* inlegrifolia, and Lakoocha, Ficu, indica and reh^osa, also F. Tnela, Rozburghii, glamerata, and oppodtifolicu From some of these an mferior kmd of caoutchouc has been obtained. The juice of the Mcus elastica of Chard war is better when drawn from the old than from the young trees, and richer m the cold season than in the hot. It is extracted bv ^n^ 7 »^f «<>"8 a foot apart, across the bark down to the wood, all round the trun£ and also the large branches, up to the very top of the tree ; the quantity which exud^ increasmg with the height of the incision. The bleeding may be safel/ repeated once DurZwhifr^ i. ^l ^."^^' ^ fresh drawn, is nearly of the consistencJof cream, and ?aJ« iTrn],,;. ^""'I*"!*! "^T ^^^^ ^^^^ * ''^^"'^ (*2 lbs.) is reckoned to be the ave mfunds of injf each bleeding of one tree; or 20,000 trees will yield about 12.000 maunds of juice : which is composed m 10 parts, of from 4 to 6 parts of water, anl of course from 6 to 4 parts of caoutchouc. The bleeding should be confined to the in tirhottoX "'' *' ""'''''" "''^ ^^ "^^'^"^' '^^ "^S^^«- vegetZn ofthe tree' Mr. Griffith says, that the richest juice is obtained from transverse incisions made nto the wood of the larger reflex roots, which are half exposed abov^^i'ounT and that ^proceeds from the bark alone. Beneath the Une of indsions, the natWes of Aslam lanru rudely folded up into the shape of a cup. He observes that the various species of Teiranthera, upon which the Moonga silkworm feeds, as also the castor oil nJant which IS the ch ef food of the Eria silkworm, do not afford a milky caoutchouc ]^e Hence It would appear that Dr. Royle's notion of caoutchouc forming a necerarv Z'iw ?/^' -r- ^^ '^^^^r^ «° in l^i« opinion. thV^^r that' can possibly be offered ; being tedious, laborious, causing the caoutchouc to be blackened in the (Jrying, and not obviating the viscidity of the juice when it is exposed to the IZ\ A ^f «™"iend8. as a far better mode of treating the juice, to work it up with the hands, to blanch it in water, and then subject it to pressure I shall pre^seTtlv describe a still better method which has receitly occurred to me, in experCndn^ upon the caoutchouc juice. This fluid, with certain precautions chiefly exXs SI long tiie ^*«nth,may be kept in the state of a creamy emulsio/for a very NEW EXPERIMENTAL EESEARCHES ON CAOUTCHOUC. The specific gravity of the best compact Para caoutchouc, taken in dilute alcohol, is 0-941567 The specific gravity of the best Assam is - - - 094297 2 » „ Sincapore - - - 0.936650 » „ Penang - - - 0-919178 Having been favoured by Mr. Sievier, formerly managing director of the Joint-Stock Caoutchouc Company, and by Mr Beale, engineer, with two different samples of cao^^ chouc juice, I have subjected each to chemical examination That of Mr. Sievier is greyish brown, that of Mr. Beale is of a milky grey colour- ^e deviation from whiteness m each case being due to the presence of aloetlc matter which accompanies the caoutchouc m the secretion by the tree. The former iuice is of the consistence of thm cream, has a specific gravity of 104125, and yields, by exposi^e upon a porcelain capsule, in a thm layer, for a few days, or by boiW for a 1^^! nutes with a little water, 20 per cent, of solid caoutchouc. The latter, though it his the consistence of pretty rich cream, has a specific gravity of only 1-0175. It yields no less than 37 per cent, of white, solid, and very elastic caoutchouc. It is interesting to observe how readily and compactly the separate little cloths or threads of caoutchouc coalesce into one spongy mass in the progress of the ebullition, particularly if the emulsive mixture be stirred ; but the addition of water is necessary to prevent the coagulated caoutchouc from sticking to the sides or bottom of the vessel and becoming burnt In order to convert the spongy mass thus formed into good caoutchouc, nothing more is requisite than to expose it to moderate pressure between the folds of a towel. By this process the whole of the aloetic extract, and other vege- table matters, which concrete into the substance of the balls and junks of caoutchouc prepared in Assam and Java, and contaminate it. are entirely separated, and an article nearly white and inodorous is obtained. Some of the cakes of American caoutchouc exhale when cut the foetor of rotten cheese ; a smell which adheres to the threads made of it, after every process of purification. In the interior of many of the balls which come from both the Brazils and East In- dies, spots are frequently found of a viscid tarry-looking matter, which, when exposed to the air, act in some manner as a ferment, and decompose the whole mass into a soft substance, which is good for nothing. Were the plan of boiling the fresh juice along with its own bulk of water, or a little more, adopted, a much purer article would be obtained, and with comparatively less trouble and delay, than has been hitherto brought into the market. I find that neither of the above two samples of caoutchouc juice affords any appear- ance of coagulum when mixed in any proportions with alcohol of 0-825 specific gravity ; and, therefore, I infer that albumen is not a necessary constituent of the juice, as Mr. Faraday inferred from his experiments published in the 2l8t voL of the Journal of the Royal Institution. The odour of Mr. Sievier's sample is slightly acescent, that of Mr. Beale's, which is by far the richer and purer, has no disagreeable smell whatever. The taste of the latter is at first bland and very slight, but eventually very bitter, from the aloetic im- pression upon the tongue. The taste of the former is bitter from the fii-st, in conse- quence of the great excess of aloes which it contains. When the brown solution which remains in the capsule, after the caoutchouc has been separated in a spongy state by ebullition, from 100 grains of the richer juice, is passed through a filter and evaporated, it leaves 4 grains of concrete aloes. Both of these emulsive juices mix readily with water, alcohol, and pyroxilic spirit^ though they do not become at all clearer ; they will not mix with caoutcJioucine (the distilled spirit of caoutchouc), or with petroleum-naphtha, but remain at the bottom of these liquids as distinct as mercury does from water. Soda caustic lye does not dis- solve the juice ; nitric acid (double aquafortis) converts it into a red curdy magma. The filtered aloetic liquid is not affected by the nitrates of baryta and silver ; it affords with oxalate of ammonia minute traces of lime. L CAOUTCHOUC MANUFACTURE. This department of operative industry has, within a few years, acquired an importance equal to that of some of the older arts, and promises, ere long, to rival even the ancient textile fabrics in the variety of its designs and applications. The manufacture of caoutchouc has, at present, three principal branches : — 1. The condensation of the crude lumps or shreds of caoutchouc, as imported from South America, India, « «voIvmg a™^. Fiv? pounds elastic lump, though a bad conductor of heat, cannot be safely touched witrthehaiid nf f^riS^ ^^'^ steaming much muddy water runs off through apertures in the bottom iJtfi Ta • l"" *^' ^r?""?^ ^^ ^^^*' ^" ^^'^^'^ trituration the various pLces becom^ nfwflr^ "J*^'' ««^^ ,«J««tic, ovoid ball, of a reddish brown colour^ This baJl is now transferred into another similar iron drum, where it is exposed to th; pricking and kneading action of 3 sets of chisel points, 6 in each set, that project from the revoh^n^ bv five «f?f ;? 'V'f .'" T^ ""'^T' "°^ "*^^^*^ ^"^^"^t/r the resistance occLtn"! dJ^m Het fh7/ ri*''^^ standing obliquely upwards from the bottomT?he drum. Here the caoutchouc is kneaded dry along with a little quickhme It soon gets yery hot; discharges n steam through the punctures, the water and a r which U Sact'^'.nd'- "^ ^'T't''^ ^"^^^"^ operation ; becomes in consequence m^re com &uri;/«l1 ?• r"^ T hour assumes the dark brown colour of stationers' rubbed Duiing all this time frequent explosions take place, from the expansion and sudden extrication of the imprisoned air and steam. ^ suaden «hfiT ^^'^ T'^'^i '^^^"^ ?'^'"'' ^^^ ^"^^ ^« transferred into a third set, whose revolving shaft being turnished both with flat pressing bars, and parallel sharp chisekperS dicular to It, exercises the twofold operation of pricking and kneading the mai so as to condense the caoutchouc into a homogeneous^^ solid. ^ Seven of the! finS Zul we ghing as above stated, 6 pounds each: are then introduced into a much W^^^^^ drum of 8im.lar construction, but of much greater strength, whose shaft is stufded aU Civ inborn ^T,^.^^^' '"''^^ ^^ ^^"^^ '^^'^^^ ^ere the 'separate balls become per- fectly incorporated into one mass, free from honeycomb cells or pores, and therefore fit for be.ng squeezed into a rectangular or cylindrical form in a sultabl^ cast-iron mould by the action of a screw-press. When condensed to the utmost in this box, th^lid i^ secured m its place by screw-bolte, and the mould is set aside for severa days I is a curious fact, that Mr. Sievier has tried to give this moulding force, by the^ 1 ydrailiS press, without effect, as the cake of caoutchouc, after being so^condensed, res {s much Z^ZT"'^T^V}''''l.^^'''' ^^' compressing action of^the screw. The cake form generally preferred for the recomposed, ground, or milled caoutchouc, is a rectanS mass, about 18 inches long, 9 inches broad, and 6 inches thick. ^ This 18 sliced into cakes for the stationer, and into sheets for making tapes and threads of caoutchouc, by an ingemous self-acting machine, in which a straifht steel blade with Its edge slanting downwards, is made to vibrate most rapidly to and fro in a horizontal SZJiT^ t'^''^^?^V^^J'^'^^"S "^^^P"^ ^' embraced at each side between two 8t ong iron bars^ 18 slowly advanced against the blade by screw-work like that of the slide-rest of a lathe. In cuttmg caoutchouc by knives of every form, it is essential that CAOUTCHOUC. 363 either the blade or the incision be nraboC:Jfa1gh?vt^^^^^^ tool would immediately stu^k fast f ^^J^f^^^^^^f^^^^^^^^^ up^over the blade in pro- downwards, the sheet which it cuts off ^P^^^/^^/.'^'^J-te The thicker slices are after- portion as it isdetached from the bottom mass of the ^ ^^^ ,^^ .^ationer. ^ards cut bv hand, with a 7"«^, ^"f^^^V Unes Fn a wooden frame. The whole- the sections teing guided ^ftangularlj by saw lines m ^^^ ^^ ^ ^^^^^ ^^^ sale price of these is now reduced to 2«. per pound S^^^^^^^ mechanism that acts desired degree of thinness, ^y ^'^:'' ZiomTlCfskeand raises it by any aliquot agaiDst a board which supports the ^«^^^,^°j/^„^^fv^^t^^^^^^^ in the same horizontal pLt of an inch, the cutting blade being caused ^^J^'^.t clXhou^ and they serve Diane These thin slices constitute what is called sheet ^f^^^^^^^^^^ ki„d ; since. Clbly for making tubes for P-^™^ J^ ^PP^^^^^^^^ coalesce. ^^y fhei." or by inflation of a W - tube ^^^^ ^-^Irse lumps of caoutchouc, into ^The mode of recomposing the ^^f,^"^^^^^^^^^^^^^ ^^^^^^ October 24, a homogeneous elastic cake, specified J^y f ;; ^^f ^^^^^ ^xhe cylinders of his miU 1836, is'not essentially ^^^^'^^'^l^^'^^^^^ not require the washing are more capacious, are open ^^/^^l^/^f;,;^^^^^ ' evious lamination and rinsing, apparatus, as the caoutchouc ^»%^^^f."\'^.?^^pen cylinder, within the space of about He completes the kneading «P«^//;«^^^° *^^', ^aU into the cheie form, in a two hours, and afterwards sq«fzes the lar^e ball so^r^ succeeds perfectly in making mould subjected to the action of an Wj'^^^^r^^^^ in^its ph/sical constf- compact cikes in this way, his «2"^^^;;^:rW^^^^ He uses a press if the power of tution from that recomposed by Mr. ^if^^^^/J^J^^.d suddenly but progressively, at 10 tons; such pressure, however -J^ -\^^^^\P^^^^^^ is Jom- intervals of two or three minutes ^^^7^«;^^^^^^^^f;;'^^^^^^^ till it is cold, when he plete. he suffers the caoutchouc to ^^^^"^^fj^f^ ^d in the slide-rest mechanism, Z iilTaTa^S^^^ '-^-' -' --'--'-' '' Mr! Beale engineer. Church-lane. WhitechapeL n. FILATURE OF CAOUTCHOUC FOR f ™^ ^^.^f J^.^t'Tlong ago as the Messrs. Rattier and Guibal mounted in f ?Jj/jf 3,',^*,^^^^^^ Tcontfauous fillet - year 1826 or 1827. a machine for cutting a disc of <^««"tchouc m ^^ j Spirally, from its circumferen^^^^ \X'ubbe t^^^^ iTo^mfufd Ihave desc^iLd thg the bottom part of a bottle ^^^^^^^J^^^^^^ machine on the same principle was made machine under the article Elastic Bands^^ A m^^^^^^ Manchester, February 1ft. the subject of a paten M/^' JP^^"^/^^^^^^^^^^ of Manchester workman- 1836; and, being constructed ^f^ijjf^^^] i^^7^ttF^ a disc of caoutehouc, from the ship, it has been ^^^l^VelertrfsK nto one Continuous length of tape. For circumference towar^s^epen^^^^^^^^ ^ ^^^^^^ ^^ India-rubber of good quality the service of this °\*^'''^^' "T ^^ -^_^ ^y i^eat and pressure into a nearly round being selected, is cut off ^^^ flattened ^Jj^ V^ ^^^^^^ ^ ^ ^^ew nut and cake of uniform thickness ™. ^f 1^ '1 ""^i^^^h may be made to revolve with any washer to the end of a ^«"^«°*f J^.f ^^^^^^ at the same time that the desired veWty by means of appropr^^^^^^^^ Pfbracircutrr knife of cast steel, made to edge of the disc of «^«^^.^„^7/ .'„\*Xne at right angles to that of the disc, and to revolve 3000 times ^er mmute, in a F^^^^f J^f^^ ^ Continuous uniform tape or fillet advance upon ita axis progrXe^y^e ^\^^V-^\Z cutting operation, the Wife and from the circumference of the cake. YV^""f, , ^ ^^ if ^ater. A succession caoutchouc are ^e/. constantly ^^^^^^ « ^ .^ .^ of threads of any desired .^f ^ V^^^^^^^J^^^^^^^ edge of a revolving steel disc. This moist state through a guide ^l^t, against the «/^^^P/^f ^^ -^^ ^mM. Rattier and operation is dexterously ^^0"^ d Pe^^^^^^ fmChalifm consisting of a series Guibal employed^ at tl^e ab«ve mennon^^^^^ ^ distances, regulated by of circular steel kmves, fixed Pf^.*"^;,\V*r^^ of knives acted against another interposed washers upon a revolving shaft , "^hicl^series ol ^^J^^^ » J^ ^^^ ^ Itilar series, placed upon ^P-^^;! ^^^^^^ ' An improved m^ificatiS; throughout its lengt^^^"^«.^'g^^J^ Wed i^the spedfication of Mr. Nickels's patent ff ^obTmt ^ ntmptys it fof rllngtS^threads the tapes made from the recomposed caoutchouc. . ^ j- ,v.v.^^ on^ in general any hollow cylinder of 364 CAOUTCHOUC. nu^ 80 as to traverse from rfghrtTlefrby tts ^^^^^^^^^ "^ « fi^ed moist, revolves upon a shaft parallel to the preTed^.r;. ^ ^J'-^^^f.r disc of steel, kept cut through the caoutchouc, so that bv thi^tm!.!!^' '"''^ * ^]'*^°^^ ^^^"^ ^^ *« ^ the hoUow^ylinder is cut sVrall^ttoVLnJ^^^^^^^ 'Sf^^"'''." «^^^> thickness of the side of the cjlindfer. Mr Spk hL i ^k *^^'*^^^^'^ f^ual to the ing hollow cylinders of recomposed caou^houcTfir^ht ^"'""^^^ H''. °^^thods of form- by such a machine. ^ caoutcnouc, for the purpose of being cut into fillets It is probable that the threads formed from f}i« i^^o* T jt- i.^^ , , from Para, are considerably strongS^ than Tho^^^ ^^*"^^^' as imported and therefore much better^ adaptfd for makW Mr^' ^'?°^. recomposed caoutchouc, When, however, the kneading operation has b Jn ^tf 'li''^''' T*""*. "^^'^^^ «*»^i^eTo?tiir^^^^^^^^^^^^^^^ caoutehouc being first machine. For this purpose they are strefched h v S • ^*? '^'^^'^. "P''^ *^« braiding reel, to 7 or 8 times thdr natu/al lenS and l/ft twf'oM^' *'* ^^ ^^/^^^°& "P«° ^^^ tension upon the reels. Thread husfJ^/aS^hr. T ''^'^•' ^^ ^^'^^ ^^^^e of 0-948732; but when it has its Istli rmt^rel^ ft^T .t^T^'^.^^°« ^^«« ^^an * state, by rubbing between the war^ palms of Ve^nni^ ''^T^ *« ''' P"«tine same piece of thJeadis reduced to 0^259 sT ThUnh ' the specific gravity of the in the process of wire-drawing where the Lno' t ''T'' ^^^^^^ '^ that exhibited tie, while it disengages much helt whioh 7^!^ ^'T g«• 3' 1,^ :*■ When the varnish is to be applied to very nice purposes, as bookbinding, Ac, it must be rubbed into a homogeneous smooth paste, by putting it m a hopper, and letting it fall between a couple of parallel iron rolls, set almost in contact The wooden frame-work of the gallery in which the water-proof cloth is manufactured, ihould be at least 50 yards long, to give ample room for extending, airing, and drying the pieces; it should be 2 yarfs wide, and not less than 5 high It js formed of ui^ right standards of wood, bound with three or four horizontal rails at the sides of the ends. At the end of the gallery, where the varnish is applied, the web which is to be smeared must be wound upon a beam, resembling m size and situation the cloth beam of the weaver's loom. This piece is thence drawn up and stretched m a horizontal direction over a bar, like the breast beam of a loom, whence it is extended m a some- what slanting du-ection downwards, and passed over the edge of a horizontal bar Above this btr, and parallel to it, a steel-armed edge of wood is aajusted so closely as to leave but a Harrow slit for the passage of the varnish and the cloth. Ihis horizontal slit may be widened or narrowed at pleasure by thumb-screws, which lower or raise the movable upper board. The caoutchouc paste being plastered thickly with a long spatula of woo^upon the down-sloped part of the web, which hes between the breast- beam and the above described slit, the cloth is then drawn through the slit by means ot cords in a horizontal direction along the lowest rails of the gallery, whereby it gets uniformly besmeared. As soon as the whole web, consisting of about 40 yards, is thus coated with the viscid varnish, it is extended horizontally upon rollers, in the upper part of the gallery, and left for a day or two to dry. A second and third coat are thea applied in succession. Two such webs, or pieces, are next cemented face to face, by nassine them, at the instant of their being brought into contact, through between a pair of wooden rollers, care being taken by the operator to prevent the formation of any creases, or twisting of the twofold web. The under one of the two pieces bein^ intended for the lining, should be a couple of inches broader than the upper one to insure the uniform covering of the latter, which is destined to form the outside of the garment The double cloth is finally suspended in a well-ventilated stove-room, till it becomes drv and nearly free from smell. The parings cut from the broader edges of the under piece, are reserved for cementing the seams of cloaks and other articles of dress. The tape-like shreds of the double cloth are in great request among gardeners, tor nailing UP the twigs of wall shrubs. Mr Walton of Sowerby-bridg^, has recently substituted sheet India-rubber for leather in the construction of fillet cards for the cotton and tow manufactures. The superior elasticity of this article is said to prove advantageous in several respects. Mr Charles Keene, proprietor of the extensive and well-organized India-rubber factory in Lambeth, obtained a patent in March, 1840, for applying a coat of caoutchouc to the outer surface of flexible leather. The varnish of caoutchouc, made with oil of turpentine, has so much lampblack incorporated with it, as to bring it to the consistence of dough. The edge of the doe-skin, buck-skin, and wash- leather being introduced between a pair of wetted iron rollers, as much of the India- rubber'compound, softened by a gentle heat, and rolled into a proper length as will cover the leather, is laid in the hollow between the leather and the moist cylindei-s. By their rotation, the coating is evenly effected. When the surface has become dry, it mav be embossed or gilt, and varnished over with a solution of shellac, with a little Venice turpentine, in alcohol. After two or three applications of this kind, the leather is passed through a pair of iron rollers, either smooth or embossed. AV hen made up articles, such as shoes or portmanteaus, Ac, are to be covered, the India-rubber varnish is used in a thinner state. — Newton's Journal^ xxiii. 357. 366 CAOUTCHOUC. CAPSTAN. 367 i CamUchouc gulphnred— Mr. Burke in describing his patented process for vulcanizing india-rubber, says, that he avoids two principal defects of the usual article, viz. its efflorescence of sulphur with an offensive odour, and its consequent decomposition and becoming rotten. He employs crude antimony (the sulphuret of that metal in fine powder), and converts it by boiling in water with soda or potash (carbonates) into the orange sulphuret of that metal (Kermes mineral) by the addition of hydrochloric acid to the fluid in slight excess. He combines this compound (after being well washed) with caoutchouc or guttA percha, either together or separately, according to the degree of elasticity which he wishes to obtain. This mixture is afterwards subjected to a heat of from 250° to 280° Fahr. He masticates the caoutchouc in the usual iron box by means of the kneading fluted revolving rollers, subjecting the whole to heat The antunonial compound is then added in quantities varying from 5 to 15 lbs., according to the strength and elasticity required in the compound. At the end of from one to two hours trituration, the block is removed from the box, and while in a warm state it is strongly compressed in an iron mould; and after being under pressure for a day or two 18 subjected to a steam heat for a couple of hours. The block thus prepared may now be cut into sheets, and afterwards divided into threads, or formed into such other articles as are desired. The patentee also mixes the flock of silk, cotton or wool, with liquefied caoutchouc and applies this compound for waterproofing cloth, previously coated with the ordinary water-proof composition. He also proposes to strengthen the gutta percha bands for driving-pulleys by affixing strips of leather to their edges; and to apply metal tips or shields to the gutta percha heels and soles of boots and shoes. The clamminess of Caoutchouc is removed by Mr. Hancock in the following manner : 10 pounds of it are rolled out into a thin sheet between iron cylinders, and at the same time 20 pounds of French-chalk (silicate of magnesia) are sifted on and incorporated with it, by means of the usual kneading apparatus. When very thin films are required (like sheets of paper) the caoutchouc, made plastic with a little naphtha, 18 spread upon cloth previously saturated with size, and when dry is stripped off. Mix- tures of caoutchouc so softened may be made with asphalt^ with pigments of various kinds, plumbago, sulphur, ^^""?^« ^'^ ^he central shaft a^ Thp li^ ""^ r\f "u^^ bevel pinion, which takes into the bevel teeth of the rin- e, ,nlth- r!!"'.?^ ?' '^^^ *^^'" l^^ ^°P ^'•^"^' ^^^ i'^ Ion? slots, with angular returns something Ike the fastening of a bayonet, which is for the purpose of enablinTthe S tL L7e1 of ttt" r • •"' -^ T' "^'^ ^'? '''''' '' ^^ '^^"? '^ •• th« outer'b aringof the axle g of the bevel pinion is also supported in the frame c, in a similar wav in order to put It m and out of gear with the teeth of the bevel ring e. A mode of S'in" Se^ ^essential; because the two toothed rings, and their drying worm and pS^^ different speeds and, of course, cannot be both in operation atfhe same time!^ ' ^ The worm of the shaft /, being placed in gear with the teeth of the rin- d on aDolv ing rotatory power thereto, by means of winches attached to the ends of^h^ shaft th^ tZt ^' ^fL"^ l^^ "^^''^'^ T"' ^" "^^^^ ^^ ^^^°J^« ^ith a slow motion, but wiU great ^lL:t tt;:dTn.^;Vay!'^ ""^^'^^ ^^' '^ ^^^ ^-« --^ - -Wmen with'c"?! J^Wl^'^v f °J^"^^^^ ^^'^ ^\^t o^.tl^e endless screw is desired, then the driving power ?p/r with^fi' K ^ r '"''''*' '° !?\^^' ^ °^ *^" ^^^^1 Pin'O"' that pinion being puTkS gear with the bevel ring e, and the endless screw withdrawn. It should, however b^ fn Po.Tt.'^''^' l^^^the patentee proposes to employ two short axles g, placed opposil^ to each other, with bevel pinions acting in the bevel-toothed ring, though only one i^ shown m the figure, to avoid confusion. He also contemplates a modificatX^ of the same contrivance m which four short axles g, placed at right angles, whp^niins o /h?>;"'^ f K"""'^ ""f ' T^ ^' '™Pl°^"^' ^"^ °^^d« «ffe<^tive in giving rotltonr mo Ln lurn'ed'brtttbV^^^^^^ °^"^"^^^^ ^^^^^^ '^ '^^ -^- -^-^ ^heYxlT^S o^dm^Io^T CARACT, is a weight used by goldsmiths and jewellers. See Assay CARBON (Carbone, Fr.; Kohlenstoff, Germ.), in a perfectly pure state, constitutes ^^mond. Carbonaceous substances are usually more or less compound, conlainirMS gen, or sometimes oxygen, and azote, along with earthy and me allic matters CarboT tolerably pure, abounds in the mineral kingdom; and, in a combined state it forms a mam constituent of vegetable and animal bodies. Anthracite is a mineral c^arc^^^^^ differing from common pit-coal in containing no bitumen, and therefore burning with- been e'JnnLT v* v^'^r '' '^' carbonaceous mass which remains after pit-coarLs been exposed to ignition for some time out of contact of air ; its volatile pkrts havin- what ttTi V '^' \^f' ^' '' ^i^P^^^y substance, of an iron-black color, a some" ^lat metallic lustre, and does not easily burn unless several pieces are kindled together tamed by the calcination of wood m close vessels, as described under the article Acetic Ac D or in piles of various shapes, covered with loam, to screen it from the fVee actSn of the atmosphere, which would otherwise consume it entirely. See Charcoal! Such withon/' y''^' ""''^^^^ '™'" ""' '""'"'^ ^^'^ ^'^'' '^' strongest heats of ou? furnaces J^ Z ,. t T^ '""J '^^"='' ^r''"^'^ ^'' ^ e'^^l^ded : it is a bad conductor of heat but conducts electricity very well. When burned, it unites with oxygen, and fonns cm bonic acid, the fixed a.r of Dr. Black, the choke^amp of the miner. When tMs Z bonic acid IS made to traverse red hot charcoal it dissolves a portion of it, and becomes carh^nicoxyde, which contains only one half of its volume of oxy4n- whereas Tr JSll l^^^^'' ^' ''^ ^^^' ^' -^" '• - -" as't;'e%rSVenf ^ Charcoal obtained by the action of a rapid fire in close vessels is not so solid ana so good a fuel as that which is made in the ancient way by the slow calcination of pyramidal piles covered with earth. One of the most economical ovens for making wood charcoal is that invented by M. Foucauld, which he calls a shroud, or abri. To construct one of these, 30 feet in diameter at the base, 10 feet at its summit, and from 8 to 9 feet high, he forms, with wood 2 inches square, a frame 12 feet long, 3 feet broad at one end, and one foot at the other. The figure will explain the construction. The uprights, A B and C D, of this frame are furnished with three wooden handles a a a, and a' a' a', by means of which tliey can be joined together, by passing through two contiguous handles a wooden fork, the frame being previously provided with props, as shown inyig. 326, and covered with loam mixed with grass. A flat cover of 10 feet diameter, made of planks well joined, and secured by four cross bars, is mounted with two trap doors, M N,ytg. 328, for giving egress to the smoke at the commencement of the operation ; a triangular C B 32T al ag hole P, cut out in the cover, receives the end of a conduit Q R S, (figs. 329 and 328,) af wood formed of three deals, destined to convey the gases and condensed liquids into the casks F G H. Lastly, a door T, which may be opened and shut at pleasure, permits the operator to inspect the state of the fire. The charcoal calcined by this abrif has been found to be of superior quality. When it is wished to change the place where the abri is erected, and to transport it to a store of new-felled timber, the frame is taken down, after beating off the clay which covers it, the joints are then cut by a saw, as well as the ends of the forks which fixed the frames to one another. This process is economical in use, simple and cheap in construction ; since all the pieces of the apparatus are easily moved about, and may be readily mounted in the forests. For obtaining a compact charcoal, for the use of artisans, this mixed process of Foucauld is said to be preferable to either the close iron cylindei or the pile. For making gunpowder-charcoal the lighter woods, such as the willow, dogwood, and alder answer best ; and in their carbonization care should be taken to let the vapors free- ly escape, especially towards the end of the operation, for when they are re-absorbed, they greatly impair the combustibility of the charcoal. By the common process of the forests, about 18 per cent, of the weight of the wood is obtained ; by the process of Foucauld about 24 per cent, are obtained, with 20 of crude pyrolisneous acid of 10 degrees Baurae. By the process described under Acetic Acid, 27 of charcoal, and 18 of acid at 6 degrees, are procured from 100 parts of wood, besides the tar. These quantities were the results of careful experimenting, and are greater than can be reckoned upon in ordinary hands. Charcoal for chemical purposes may be extemporaneously prepared by calcining piecec of wood covered with sand in a crucible, till no more volatile matter exhales. The charcoal of some woods contains silica, and is therefore useful for polishing metals. Being a bad conductor of heat, charcoal is employed sometimes in powder to incase small furnaces and steam-pipes. It is not affected by water; and hence the extremities of stakes driven into moist ground are not liable to decomposition. In like manner casks when charred inside preserve water much better than common casks, because they furnish no soluble matter for fermentation or for food to animalcules. Lowitz discovered that wood charcoal removes offensive smells from animal and vege- table substances, and counteracts their pratrefaction. He found the odor of succinit 370 CARBON. and benzoic acids, of bugs, of empyreumatic oils, of infusions of valerian, esseare o! wormwood, spirits distilled from bad grain, and sulphureous substances were all absorb- able by treshly calcined charcoal properly applied. A very ingenious filter has been con- siructea lor purifying water, by passing it through strata of charcoal of different fineness. ♦v-^ V ^^^'1^°^ ^ burned, one third of the heat is discharged by radiation, and two thirds by conduction. n j > r y^^^^'^lr'!? ^?^^^ °^ i.^^ ^"^"*^*y ^^ charcoal yielded by different woods was pub- hshed by Mr. Mushet, as the result of experiments carefuUy made upon the small scale. He says, the woods before being charred were thoroughly dried, and pieces of each kind were selected as nearly alike in every respect as possible. One hundred parts of each sort were taken, and they produced as under : — Lignum Vitae Mahogany - Laburnum Chestnut - Oak - Walnut - Holly Beech Sycamore - Elm - Norway Pine SaUow Ash - Birch Scottish Pine afforded 26-0 of charcoal of a grayish color, resembling coke. - 25-4 tinged with brown, spongy and porous. - 24-5 velvet black, compact, very hard. - 23'2 glossy black, compact, fiim. - 22*6 black, close, very firm. - 20-6 dull black, close, firm. - 19'9 dull black, loose and bulky. - 19*9 dull black, spongy, firm. - 19-7 fine black, bulky, moderately firm. - 19*5 fine black, moderately firm. - 19-2 shining black, bulky, very soft. - 18-4 velvet black, bulky, loose and sof^. - 17*9 shining black, spongy, firm. - 17-4 velvet black, bulky, firm. - 16*4 tinged with brown, moderately firm. Messrs. AUen and Pepys, from 100 parts of the following woods, obtained tU quanti- kes of charcoal as under : — o , ^ ^ »». Beech Mahogany Lignum Vitae 15-00 15-75 17-25 Oak Fir . Box - 17'40 - 18-17 - 20-25 It IS observable that the quantities obtained by Messrs. Allen and Pepys are in general less than those given by Mr. Mushet, which may be owing to Mr. Mushet not having applied sufficient heat, or operated long enough, to dissipate the aqueous matter oC the gaseous products. To those persons who buy charcoal by weight, it is important to purchase it as soon alter it is made as possible, as it quickly absorbs a considerable portion of water from toe atmosphere. Different woods, however, differ in this respect. Messrs. AUen and I'fli^jrs found, that by a week's exposure to the air, the charcoal of Lignum Vitaj gained Fir - . . Box - Beech - Oak - Mahogany - 9-6 per cent. 13-0 ditto. 14-0 ditto. 16-3 ditto. 16-5 ditto. 18-0 ditto. The following is a tabular view of the volumes of the different gases which were absorbed m the course of 24 hours, by one volume of charcoal, in the experiments of ^heodore de Saussure, which were conducted in a way likely to produce correct results. Each portion of charcoal was heated afresh to a red heat, and allowed to cool under mercury. When taken from the mercury, it was instantly plunged into the vessel Ammoniacal gas - - 90 Muriatic acid gas - - 85 Sulphurous acid - - 65 Sulphurated hydrogen - 55 Nitrous oxyde - - - 40 Carbonic add gas - - 36 I Bicarbureted hydrogen - 35-00 Carbonic oxyde - - 9-42 Oxygen gas - - - 9-25 Nitrogen - - . 7-50 Carbureted hydrogen - 5-00 Hydrogen gas - - 1*75 Neumann who made many experiments on charcoal, informs us, that for the reduction of the metallic oxydes, the charcoal of the heavier woods, as that of the oak and the beech, is preferable, and that, for common fuel, such charcoal gives the greatest heat, and requires the most plentiful supply of air to keep it burnine; while those of the lighter woods preserve a glowing heat with a much less draught of air; and that for purposes Where it is desirable to have a steady and a still fire, charcoal should be employe' nearly a cubic inch of the gas for every grain in weight. CARBONATE OF AMMONIA. A salt called in modem chemistry sesqui-car- bonale, to denote its being composed of one and a half equivalent primes of carbonic acid, and one of ammonia. It consists by my analysis of 55-89 carbonic acid, 28*86 ammonia, and 15-25 water, in 100 parts. It is generally prepared by mixing from 1^ to 1| parts of well-washed dry chalk, with 1 of sal-ammoniac, introducing the mixture into an earthen or cast-iron retort, or subliming pot, and exposing it to a heat gradually raised to redness. By double decomposition, the ammonia is volatilized in combination with the car'oonic acid of the chalk, and the vapors are received in a condensing receiver made either of glass, stone ware, or lead. The chlorine of the sal-ammoniac remains in the reiort, associated with the basis of the chalk in the state of chloride jf calcium. Some ammonia gas escapes during the process. Tilt saline mass thus sublimed is purified by a second sublimation in glass or salt- glazed earthen vessels. The salt may be obtained, by the above method carefully con- ducted, in rhomboidal octahedrons, but it is generally made for the market in a compf cl semi-crystalline white cake. It has a pungent ammoniacal smell ; a hot, pungent, alkv line taste ; a strong alkaline reaction, and dissolves in two parts of cold water. It must be kept in well-closed vessels, as by exposure to the air a portion of its ammonia exhales, and it passes into the state of the scentless bi-carbonate. It is employed much in medi- cine, chemical analysis, and by the pastry-cooks to give sponginess to their cakes, in cohf sequence of its volatilization from their dough in the oven. See Sal-Ammoniac. For the other carbonates used in .the arts, see their respective bases ; copper, lead* lime, &c. 372 CARBURET OF SULPHUR. CARBONIC ACID (Jade carbonique, Fr. ; Kohlensaure, Germ.) consists of I pnmc equivalent of carbon=6-l25-f-2 of oxyffen= 16-026, whose joint sum=22-151, represents the atomic weight or combining ratio of this acid, in the neutral or protocarbonate salts. Its composition by volume is stated under Carbon. Its natural form is a gas, whose specific gravity is 1-5245, compared to atmospheric air 1-000; and being so dense, it may be poured out of one vessel into another. Hence it v/as called at^'fiist aerial acid. From its existing copiously, in a solid state, in limestones and the mild alkalis, It was styled fixed air by its proper discoverer, Dr. Black. About one volume of It exists m 1000 volumes of common atmospheric air, which may be made manifest *y the crust of carbonate it occasions upon the surfa-e of lime Water. Carbonic acid gas IS found accumulated in many caverns of volcanic districts, and particularly in the grotto dei cam at Pausilippo, near Puzzuoli ; being disengaged in such circumstances by the action of subterranean fire, and, possibly, of certain acids, upon the limestone strata. It often issues from fountains in copious currents, as at Franzensbrunn, near Eger, m Polterbrunnen ; near Trier; and Byrreshorn. This acid gas occurs also frequently in mines and weUs, being called choke damp, from its suffocating quality. Its presence may, at all times, be detected, by letting down a li-hted candle, suspended from a string, mto the places suspected of containing this mephitic air. It exists, m considerable quantities, in the water of every pump well, and gives it a fresh and pleasant taste. Water, exposed some time to the air, loses these aerial particles, and becomes vapid. Many springs are highly impregnated with carbonic acid gas, and form a sparkling beverage; such as the Selterswasser, from Selters upon the Lahn, in the grand dutchy of Nassau ; of which no less than two millions and a half of bottles are sold every year. A prodigious quantity of a similar water is also artificially prepared in Great Britain, and many other countries, under the name of aerated or soda water. Carbonic acid occurs in nature, combined with many salifiable bases; as in the carbonates of soda, baryta, strontia, magnesia; the oxydes of iron, manganese, zinc, copper, lead, &c. From these substances it may be separated, generally "speaking, br strong Ignition, or, more readily, by the superior affinity of muriatic, sulphuric, or nitric acid, for the earth or metallic oxyde. It is formed whenever ve-etable or animal substances are burned with free access of air, from the union cf their carbonaceous principle with atmospheric oxygen. It is also formed in all cases of the spontaneous decomposition of organic substances, particularly in the process of fermentation ; and constitutes the pungent, noxious, heavy gas thrown off, in vast volumes, from beer vats. See Distillation and Fermentation. Carbonic acid is also generated in the breathing of animals; from 4 to 5 per cent., in volume, of the inhaled oxygen bein? converted, at each expiration, into this gas, which contaminates the air of crowded apartments and renders ventilation essential to health, and even to life; witness the horrible catastronhe of the Black-hole at Calcutta. Carbonic acid gas is destitute of color, has a sourish, suffbcating smell, an acidulous pungent taste, imparts to moist, but not dry, litmus paper, a transient reddish tint, and weighs per 100 cubic inches, 46| grains; and per cubic foot, 803^ grains; a little more than 3 J oz. avoirdupoise. A cubic foot of air weighs about two thirds of that quantity or 527 grams. It may be condensed into the liquid state by a pressure of 40 atmos- pheres, and this liquid may be then solidified by its own sudden spontaneous evapora- tion. If air contain more than 15 per cent, in bulk of this gas, it becomes unfit for respiration and combustion, animal life and candles being speedily extint'uished by it. ° Before a person ventures into a deep well, or vault containing fermenting materials he should introduce a lighted candle into the space, and observe how it burns. Car- bonic acid, being so much denser than common air, may be drawn out of cellars or fermenting tubs, by a pump furnished with a leather hose, which reaches to the bottom Quicklime, mixed with water, may be used also to purify the air of a sunk apartment, by Its affinity for, or power of, absorbing this aerial acid. See Mineral Waters and Soda CARBONIC OXYDE. See the article Carbon. CARBUNCLE. A gem highly prized by the ancients ; most probably a variety of the noble garnet of modern mineralogists. CARBURET OF SULPHUR, called also sulphuret of carbon, and alcohol of sulphur, IS a limpid volatile liquid possessing a penetrating fetid smell, and an acrid burning taste. Its specific gravity is 1-265 ; and its boiling point is about 1 12° Fahr It evaporates so readily, and absorbs so much heat in the vaporous state, that if a tube con- tammg quicksilver, surrounded with lint dipped in this liquid, be suspended in the re ceiver of an air-pump on making the vacuum, the quicksilver will be congealed It con sists of 15-8 carbon and 84-2 sulphur, in 100 parts; being two equivalent primes of tht latter to one of the former. CARD CUTTING. 373 CARBURETED HYDROGEN. A compound of carbon and hydrogen, of which ttiere are several species— such as oil-gas, coal-gas, defiant gas, oil of lemons, otto of roses', oil of turpentine, petroleum, naptha, napthaline, oU of wine, caoulchoucme, and ** CARDS,* PLAYING. {Cartes a jou&r, Fr. ; Karten, Germ.) Mr. de la Rue obtained^ in February, 1832, a patent for certain improvements in the manufacture of playing cards, which he distributed under three heads ; first, printing the pips, and also the picture or court cards, in oil colors by means of types or blocks ; secondly, effecting the same ir oil colors by means of lithography ; and thirdly, gilding or sUveiing borders, and other parts of the characters, by the printing process, either by types, blocks, or lilho- In the ordinary mode of manufacturing playing cards, their devices are partly produced by copperplate printing, and they are filled up with water colors by the means called The patentee does not propose any material alteration in the devices or forms u^-on ihe cards but only to produce them with oil colors ; and, to effect this, he follows precisely the same mode as that practised by calico printers. A set of blocks or types properly devised, are produced for printing the different pips of hearts, diamonds, spades, and clubs, or they are drawn, as other subjects, in the usual way upon stone. The ink or color, whether black or red, is to be prepared from the best French lamp-black, or the best Chinese vermilion ground in oil, and laid on the types and blocks, or on the stone, in the same way as printers' ink, and the impressions taken-on to thick drawing paper by means of a suitable press in the ordinary manner ol printing. , , , • /. • • • j/r The picture or court-cards are to be produced by a series of impressions m ditlerent colors, fitting into each other exactly in the same way as in printing paper hangings, or silks and calicoes, observing that all the colors are to be prepared with oil. For this purpose a series of blocks or types are to be provided for each snbiect, and which, when put together, will form the whole device. These blocks are to be used sepa- rately, that is, all the yellow parts of the picture, for instance, are to be printed at one impression, then all the red parts, next all the flesh color, then the blue portions, and so on, finishing with the black outlines, which complete the picture. If the same is to be done by lithography, there must be as many stones as there are to be colors, each to print its portion only ; and the impression, or part of the picture given by one stone, must be exactly fitted into by the impression given from the next stone, and so on until the whole subject is complete. A superior kind of card is proposed to be made, with gold or silver devices m parts of the pictures, or cold or silver borders round the pips. This is to be effected by printing the lines which are to appear as gold or silver, with gilders' size, in place of ink or color ; and immediately after the impression has been given, the face of the card is to be powdered over with gold dust, silver, or bronze, by means of a soft cotton or wool dabber, by which the gold, silver, or bronze will be made to adhere to the picture, and the superfluous portions of the metal will wipe off by a very slight rubbing. When the prints are perfectly dry, the face of the card may be polished by means of a soft If it should be desirable to make these improved cards to resemble ivory, that may be done by preparing the face of the paper in the first instance with a composition of size and fine French white, and a drying oil, mixed together to about the consistency of cream ; this is to be washed over the paper, and dried before printing, and when the cards are finished they will exactly resemble ivory. The only thing remaining to be described, is the means by which the successive impres- sions of the types, blocksp or stones, forming the parts of the pictures, are to be brought exactly to join each othev,so as to form a perfect whole design when complete; this is by printers called registerine, and is to be effected much in the usual way, by points in the tympan of the press, or by marks upon the stones. The parts of the subject having been all accurately cut or drawn to fit, small holes are to be made with a fine awl through a quire or more of the paper at once, by placing upon the paper a gauge-plate, having marks or guide-holes, and by observing these, the same sheet laid on several times, and always made to correspond with the points or marks, the several pails of the picture must inevitably register, and produce a perfect subject. , . „ . J • . r CARD CUITING. Mr. Dickinson's patent machine for cutting cards, consists of a pair of rollers with circular revolving cutters, the edges of which are intended to act against each other as circular shears, and the pasteboards in passing between these rollers are cut by the circular shears into cards of the desired dimensions. These rollers are mounted in suitable standards, with proper adjustments, and are made to revolve by 374 CARDS. CARDS. 375 ■ band and pulley connected to the axle of a crank, or by any other convenient means. Fig. 330 is a front view ol this machine; a a and bb are the two rollers, the upper one turning upon an extended axle, bearing in the standards, the lower one upon pivots. These rollers are formed by a series of circular blocks, between a series of cir- cular steel cutters, which are slidden on to iron shafts, and held together _ upon their axle by nuts ^ screwed up at their ends. The accurate adjustment of the cutlers is of the first importance to their correct performance; it is therefore found necessary to introduce spiral springs within the blocks, in order . to press the cutters up to their proper beanngs. A section of one of the blocks is shown at Jig. 332, and an end "new of the same at fig. 333, with the spiral springs inserted. At the outer extremity of the axle of the roller a^a risger c, is attached, whence a band passes to a pulley d. on the crank shaft «, to which a fly-wheel/, is affixed, for the purpose of rendering the action uniform. Rotatory motion being given to the crank shaft, the npper roller is turned, the lower roller moving at the same time by the friction against the edges of the cutters. Fig. 331 is an end view of the rollers, showing the manner in which the pasteboards are guided and conducted between the cutlers. In the front of the machine a moveable frame g, is to be placed, for the purpose of receiving the pasteboards, preparatory to cut- ting them into cards, and a stop is screwed to this frame for the edge of the pasteboard to bear against, which stop is adjustable to suit different sizes. From the back part of this frame an arm A, extends, the extremity of which acts against the periphery of a ratchet wheel t, fixed at the end of the roller b, and hence, as the roller goes round, the frame is made to rise and fall upon its pivots, for the purpose of guiding the pasteboard up to the cutters ; at the same time a rod fc, hanging in arms from the sides of the standards (shown by dots in fig. 330), falling upon the pasteboard, confines it, while the cutters take hold, and racks corresponding with the indentations of the rollers are placed as at / /, by means of which the cards, when cut, are pushed out of the grooves. As 7drious widths of cards will require to be cut by this machine, the patentee pro- poses to have several pairs of rollers ready adjusted to act together, when mounted in the standards, in preference to shifting the circular cutters, and introducing blocks of greater or less width. The second part of the invention is a machine for pasting the papers, and pressing the sheets together to make pasteboard. This machine consists of several reels (we suppose rollers are intended) on which the paper is to be wound, along with a paste trough, and rotatory brushes. The several parts of this machine, and their operations in making pasteboard, are described in the specification, but the patentee having omitted the letters of reference in the drawing which he has enrolled, it becomes difficult to explain it. As far as we are enabled to understand the machine, it appears, that damped paper is to be wound upon two rollers, and conducted from thence over two other rollers ; that two fluted rollers revolving in the paste trough are to supply paste to two circular brushes, and that by those brushes the papers are to be pasted upon one side, and then pressed to- gether, to make the pasteboard ; after this, the pasteboard is to be drawn on to a table, and to remain there until sufficiently dry to be wound upon other rollers. By comparing this description with the figure, perhaps the intended operations of the machine may be discovered : it is the best explanation we are enabled to give. CARDS (Cardes, Fr. ; Kardeuj Germ.) are instruments which serve to disentangle the fibres of wool, cotton, or other analogous bodies, to arrange them in an orderly la^ or fleece, and thereby prepare them for being spun into uniform threads. The finenesf and the levelness of the yam, as well as the beauty of the cloth into which it enters. deoend as much upon the regularity and perfection of the cardmg, as upon any subsequent oocration* of the factory. The quality of the carding depends more upon that ol the cards than upon any attention or skiU in the operative ; since it is now nearly an automa tic nrocess, conducted by young women called card-tenters. Cards ax^e formed of a sheet or fillet of leather pierced with a multitude of smaQ hol^, in which are implanted small staples of wire with bent projecting ends called teeth. Thus every piece of wire is double toothed. The leather is afterwards applied to a flat or cvHndrical surface of wood or metal, and the co-operation of two or more such sur- faces constitutes a card. The teeth of cards are made thicker or slenderer, according as its filaments to be carded are coarser or finer, stifi'er or more pliant, more valuable or cheaper. It is obviously of great importance that the teeth should be all alike, equably distributed, and equally inclined over the surface of the leather, a degree of precision which is scarcely possible with handwork. To judge of the difficulty of this manipu- Ulion we need only inspect the annexed figures. The wire must first be bent at ngJif angles in c and d, fig. 336, then each branch must receive a second bend m a and 6 at a determinate obtuse angle, invariable for each system of cards. It is indispensable that the two angles c a « and d 6 / be mathematically equal, not only as to the twin teeth of one staple, but through the whole series ; for it is easy to see that if one of the teeth be more or less sloped than its fellow, it will lay hold of more or less wool than it, and render the cardin*' irregular. But though the perfect regularity of the teeth be imporiant it is not the sole condition towards making a good card. It must be always kept in view that these teeth are to be implanted by pairs in a piece of leather, and kept in it by the cross part ed. The leather must therefore be pierced with twin holes at the distance c d ; and pierc- ed in such a manner, that the slope of the holes, in reference to the plane of the leather, be invariably the same ; for otherwise the length of the teeth would vary with this angle of inclination, and the card would be irregular. • ♦!, * ♦!, i ♦!. . A third condition essential towards producing perfect regularity, is that the leather ought to be of the same thickness throughout its whole surface, otherwise the teeth, though of the same length and fixed at the same ande, would be rendered unequal by the different thicknesses of the leather, and the operation of cardmg would be m consequence a m ■ * • a »^ immmm 336 extremely defective. Fig. 334 shows the card teeth actmg against each other, as indica- Sbv the arrows in two opposite directions ; in fig. 336 they work one way. Of lite ^earl very complex but complete and well-acting machines have been con- structerfor splitUng the leather or equalizing it by shaving, for bending and cutt.ng t^e wires and implanUng them in the leather, into holes pierced with perfect regularity. Card machiiTs which fashion the teeth with great precision and rapidity, and pierce the lealherhave bein for a considerable time in use at Halifax, in Yorkshire, a town famo^ foflhe excellence of its card-cloth, as also at Leeds, Glasgow, and several other places. The wires and the leather thus prepared are given out by the manufacturer to women and "^Tt^^^^I^ZJ^^^' ^ mounted that every alternate thread of the one may be raised, so as to form a suffi- cient shed-way for the shuttle, without depressing the other in the least. Then suppc^ another web placed above the former, at such a distance that it will exactly touch the convexity of those threads of the former which are raised. Then, if the threads of the latter web are sunk while the others are raised, the two would be entirely in- corporated. But if this be only partially done, that is, at particular places, only those parts immediately operated upon will be affected by the action of the apparatus. If the carpet is a two-colored pattern, as black and red, and if upon the upper sur- 8C2 380 CARPET. ill: I SB iJ If' face, as extended in the loom, red flowers are to be represented upon a black ground, then all those specie? of design paper which are colored may be supposed to represent the red, and those which are vacant the black. Then counting the spaces upon the paper, omit those which are vacant, and cord those which are colored, and the effect will be produced. But as the two webs are to be raised alternately, whatever is corded for the first handle must be passed by for the second, and vice versa ; so that the one will form the flower, and the other the ground. The board by which the simples are regulated appears at F. D shows the weights. CARPET— Nkw Patent. Mr. Simcox, of Kidderminster, has patented an inventiou for an improved manufacture of carpets, in whicli, by dispensing with the Jacquard loom, as well as the iron wires and tags usually employed to produce terry fabrics, such as Brussels carpets and coach-lace, he can work his machinery at greater speed and more economically. His second improvement relates to the manufacture of fabrics with cut pile, such as Wilton or Axminster carpets. He makes a ribbed fabric, greatly resembling the Brussels carpet., by a combination of woollen and linen warp and weft, arranged in such a manner that the woollen warp, in the form of a ribbed surface, may constitute the face of the fabric, while the linen warp forms the ground or back of tlie fabric. The plan he prefer^ as most resembling the Brussels, consists in weaving the fabric as nearly as possible in the ordinary way, except that, instead of inserting a tag or wire to form the rib or terry, the patentee throws in a thick shoot or weft of woollen or cotton, over which the woollen warp is drawn, and forms a rib ; the woollen warp being afterwards bound down with a linen shoot or weft in the ordinary way. The woollen warp employed being all of one colour, the fabric produced will be plain or unornamented, with a looped or terry pile ; and upon this fabric any design may be printed from blocks. The looms differ from the former chiefly in the employment of two separate shuttles, one for the woollen and one for the linen weft These shuttles are both thrown by the same pickers and the same picking-sticks, and consequently the shuttle boxes must be moved up and down as may be required, in order to allow the picker to throw the proper shuttle. It will also be necessary to work the healds in a suitable manner to form the proper shreds, in order that the woollen face may be properly bound to the linen ground. Figures illustrating the construction of his loom are given by the patentee. The second part of his invention relates to the production of fabrics with a cut pile, like the Axminster or Wilton rugs or carpets. The ordinary mode of making some of these fabrics is to weave the pattern in by means of a Jacquard apparatus, and pass the woollen warp over a rod or tag, which is afterwards cut by passing a suitable knife along it, thereby producing the cut pile. The patentee produces the design and surface of the fabric from the weft in place of the warp as heretofore. For this purpose the weft is made to consist of thick woollen shoots, which must be painted or stained with suitable colours, precisely as the woollen warps have been heretofore done; and the woollen shoot, when thrown in, is, by means of suitably formed hooks, pulled up and turned into loops, which, when they are properly secured to the foundation or ground of the fabric, are afterwards cut by means of knives or cutting instruments, with which the hooks are furnished, for the purpose of releasing them from the loops, and producing the cut pile. The patentee observes, that cotton and other cheap materials may be em- ployed with great advantage in the production of some of these fabrics. — NewtoiCs Journal, xxxiv. 167. Another invention of improvements in manufacturing figured fabrics, princi- pally designed for the production of carpeting, patented by Mr. James Templeton, of Glasgow, consists in producing the pattern either on one or both sides of the fabric, by meal's of printed weft ; also in the use of printed parti-coloured fur or weft, in the manu- facture of Axminster carpet, and other similar fabrics. This invention is also applicable to the production of figured chenOle weft for the manufacture of chenille shawls. Newtoris Journal, xxxvii. 148. Carpets, Printed. Mr. Wood has taken a patent for weaving and printing carpets, using an ordinary Brussels carpet loom. After putting in the wire, or otherwise forming the loop, he throws in the usual linen shoot, on the face, to bind it; and then, for the back shoot, he throws in a thick soft weft. Or, to make a better edge and more elastic back, he employs the ordinary two linen shoots, — one on the face and the other in the back, — and then (or before throwing in the second linen shoot) he draws down only one-half of the lower portion of the linen warp (being one-quarter of the whole), and throws in the thick shoot, which is driven up by the batten or lay, so as to cover the second linen shoot, which is then inside the fabric : from the thick shoot being bound only by each alternate yarn of the warp, it will be more elastic than if bound more closely by using every yarn ; whilst the second linen shoot, having half the warp over it, holds down the face or first shoot ; and any inequality in the taking up of the linn CARTHAMUS. 381 warp, by one portion of it binding in a ^cater substance than the other, is remedied by drawing down the different portions in succession. In printing Brussels and other pile carpets, the patentee first provides a table, long enough to receive the entire length or piece of the carpet to be printed ; at each end of the table there is a frame of the same height or level, sufficiently long to receive the cylinder printing machine when off the fabric ; and on the surface of the table the printing blanket is laid between two rails or guides, which are fixed at exactly the saine distance apart as the carpet is wide, so as to keep it in one position, iind to form the guides for the printing cylinders. The carpet is fastened to one end of the table, and w then laid on the top of the same, and drawn tight at the other end by a roller, which is furnished with a ratchet wheel and click. Tlie printing cylinders are mounted in a movable frame, containing a corresponding number of colour cans and feeding rollers, to supply them with colour. This printing apparatus is passed over the table, and between the guide rails (the patterns on the cylinder being coloured, and bearing upon the carpetX to the frame at the other end of the table, and then back again ; and this process is repeated until the fabric is sufiiciently coloured. In order to insure each part of the pattern or printing surface coming again and again on the same place, toothed wheels are affixed on the axis of the printing cylinders, which geer into racks fixed on the sides of the table; so that, however frequently the printing apparatus passes over the fabric, every part of the pattern will fall on the same place. Instead of the printing apparatus being passed back again over same table, it may, by the appli- cation of movable frames at the end of the table, be moved sideways on to another table, and so successively. — Newtm's Journal, -sxsiw. 2bQ. CARTHAMUS, or safflower (carthamus tinctorius), (Carihame, Fr. ; F rher dtsiel. Germ.), the flower of which alone is used in dyeing, is an annual plant cultivated m Spain Egypt, and the Levant. There are two varieties of it — one which has large leaves, and the other smaller ones. It is the last which is cultivated in Egypt, where it forms a considerable article of commerce. j rrv « ♦ Carthamus contains two coloring matters, one yeUow and the other red. Ihe tirst alone is soluble in water ; its solution is always turbid : with re-agents it exhibits the characters usually remarked in yellow coloring matters. The acids render it lighter, the alkalis deepen it, giving it more of an orange hue : both produce a «anall dun pre- cipitate, in consequence of which it becomes clearer. Alum forms a precipitate of a deep yellow, in small quantity. The solution of tin and the other metallic solutions cause pre- cipitates which have nothing remarkable in them. The yellow mailer of carthamus is not employed ; but in order to extract this portion, the carthamus is put into a bag, which is trodden under water, till no more color can be pressed out. The flowers, which were yellow, become reddish, and lose m this opera tion nearly one half of their w«ight. In this state they are used. For extracting the red part of carthamus, and thereafter applying it to stuff, the prop- erty which alkalis possess of dissolving it is had recourse to, and it is afterwards pre- cipitated by an acid. „ . . , , • ,. v The process of dyeing consists, therefore, m extracting the coloring matter by means oi an alkali, and precipitating it on the stuff by means of an acid. It is this fecula which serves for making the rouge employed by ladies. As to this rouge, the solution of carthamus is prepared with crystallized carbonate or soda, and it is p?ecipitaled by lemon juice. It has been remarked that lemons, begin- ning to spoil, were filler for this operation than those which were less ripe, whose juice retained much mucilage. After squeezing out the lemon juice, it is left to settle for some days. The precipitate of carthamus is dried at a gentle heat upon plates of stone-ware ; from* which it is detached and very carefully ground with talc, which has teen reduced tO a very subtile powder, by means of the leaves of shave-grass (presle), and successively passed through sieves of increasing fineness. It is the fineness of Ihe talc, and the greater or less proportion which it bears to the carthamus precipitate, which constitute the dif- ference between the high and low priced rouges. Carthamus is used for dyeing silk, poppy, nacarat (a bright orange-red), cherry, rose color and flesh color. The process differs according to the intensity of the color, and the greater or less tendency to flame color that is wanted. But the carthamus bath, whose application may be varied, is prepared as follows : , ^ , i The carthamus, from which the yellow mailer has been extracted, and wliose lumps have been broken down, is put into a trough. It is repeatedly sprinkled with cendres ' pravelees (crude pearlashes), or soda (barilla) well powdered and sifted at the rate of 6 pounds for 120 lbs. of carthamus; but soda is preferred, mixing carefully as the alkaU is introduced. This operation is caUed amesher. The amestred carthamus is put into a small trough with a grated bottom, first lining this trough with a closely woven cloth. "When it is about half filled, it is placed over the large trough, and cold water is poured into the upper one, till ihe lower becomes full. The carthamus is then set over another 382 CASE-HARDENING. '.\\ trongh, till the water comes from it almost colorless. A little more alkali is now mixed! with It, and fresh water is passed through it. These operations are repeated till the car- thamus be exhausted, when it turns yellow. After distributing the silk in hanks upon the rods, lemon juice, brought in casks from Provence, is poured into the bath till it becomes of a fine cherry color; this is called turning the bath (virer le bain). It is well stirred, and the silk is immersed and turned round the skein-sticks in the bath, as long as it is perceived to take up the color. For ponceau (poppy color), it is withdrawn, the liquor is run out of it upon the peg, and it is turned through a new bath, where it is treated as in the first. Aflei this it is dried and passed through fresh baths, continuing to wash and dry it between each operation, till it has acquired the depth of color that is desired. When it has reached the proper pomt, a brightening is given it by turning it round the sticks seven or eight times in a bath of hot water, to which about half a pint of lemon juice for each pailful of water has been added. When silk is to be dyed ponceau or flame color, it must be previously boiled as for white ; it must then receive a slight foundation of annotto, as explained in treating of this substance. The silk should not be alumed. The nacaratsy and the deep cherry colors, are given precisely like the ponceauxy only they receive no annotto ground ; and baths may be employed wh'ch have served for the ponceauy so as to complete their exhaustion. Fresh baths are not made for the latter colors, unless there be no occasion for the poppy. With regard to the lighter cherry-reds, rose color of all shades and flesh colors, they are made with the second and last runnings of the carthamus, which are weaker. The deepest shades are passed through first. The lightest of all these shades, which is an extremely delicate flesh color, requires a little soap to be put into the bath. This soap lightens the color, and prevents it from taking too speedily, and becoming uneven. The silk is then washed, and a little bright- ening is given it, in a bath which has served for the deeper colors All these baths are employed the moment they are made, or as speedily as possible, because they lose much of their color upon keeping, by which they are even entirely destroyed at the end of a certain time. They are, moreover, used cold, to prevent the color from being injured. It must have been remarked in the experiments just described, that the caustic alkalis attack the extremely delicate color of carthamus, making it pass to yellow. This is the reason why crystals of soda are preferretf to the other alka- line matters. In order to diminish the expense of the carthamus, it is the practice in preparing the deeper shades to mingle with the first and the second bath about one fifth of the bath of archil. Dobereiner regards the red coloring matter of carthamus as an acid, and the yellow as a base. His carlhamic acid forms, with the alkalis, colorless salts, decomposed by the tartaric and acetic acids, which precipitate the acid of a bright rose-red. Heat has a re- markable influence upon carthamus, rendering its red color yellow and dull. Hence, the colder the water is by which it is extracted, the finer is the color. Light destroys the color very rapidly, and hitherto no means have been found of counteracting this efiect. For this reason this brilliant color must be dried in the shade, its dye must be given in a shady place, and the silk stufls dyed with it must be preserved as much as possible from the light. Age is nearly as injurious as light, especially upon the dye in a damp state. The color is very dear, because a thousand parts of carthamus contain only five of it. In preparing the finest rouge, the yellow coloring matter being separated by washing with water, the red is then dissolved by the aid of alkali, and is thrown down on linen or cotton rags by saturating the solution with vegetable acid. The color is rinsed out of ^ese rags, dissolved anew in alkalis, and once more precipitated by lemon juice. The oest and freshest carthamus must be selected. It is put into linen bags, which are placed in a stream of water, and kneaded till the water runs off colorless. The bags are then put into water soured with a little vinegar, kneaded till the color is all expelled, and finally rinsed in running water. By this treatment the carthamus loses nearly half its weight. 6633 cwts. of safflower were imported into the United Kingdom in 1835, of which 2930 cwts. were retained for internal consumption. CASE-HARDENING is the name of the process by which iron tools, keys, &c., have their surfaces converted into steel. Steel when very hard is brittle, and iron alone is for many purposes, as for fine keys, far too soft. It is therefore an important desideratum to combine the hardness of a steely surface with the toughness of an iron body. These requisites are united by the process of case-hardening, which does not differ from the making of steel, except in the shorter duration of the process. Tools, utensils, or ornaments, intended to be polished, are first manufactured in iron and nearly finished, after which they are put into an iron ' m CASHMERE. 383 box, together with vegetable or animal charcoal in powder, and cemented for a certain time. This treatment converts the external part into a coating of steel, which is usually very thin, because the time allowed for the cementation is much shorter than when the whole substance is intended to be converted. Immersion of the heated pieces into water hardens the surface, which is afterwards polished by the usual methods. Moxon, in his Mechanic Exercises, p. 56, gives the following receipt for case-hardening :— " Cow's horn or hoof is to be baked or thoroughly dried and pulverized. To this add an equal quantity of bay salt ; mix them with stale chamber-ley or white wine vinegar : cover the iron with this mixture, and bed it with the same in loam, or enclose it in an iron box; lay it on the hearth of the forge to dry and harden : then put it into the fire, and blow till the lump have a blood-red heat, and no higher, lest the mixture be burnt too much. Take the iron out, and immerse it in water to harden." I consider the vinegar to be quite superfluous. v 4 «i>' I shall now describe the recent application of prussiate (ferrocyanate) of potash to tnis purpose. The piece of iron, after being polished, is to be made brightly red-hot, and then rubbed or sprinkled over with the above salt in fine powder, upon the part intended to be hardened. The prussiate being decomposed, and apparently dissipated, the iron if to be quenched in cold water. If the process has been well managed, the surface of the metal will have become so hard as to resist the file. Others propose to smear over the surface of the iron with loam made into a thin paste with a strong solution of the prussiate, to dry it slowly, then expose the whole to a nearly white heat, and finally plunge the iron into cold water, when the heat has fallen to dull redness. See CASHMERE or CACHEMERE, a peculiar textile fabric first imported from the kingdom of Cashmere, and now well imitated in France and Great Britain. The maferial of the Cashmere shawls is the downy wool found about the roots of the hair of the Thibet goat. The year 1819 is remarkable in the history of French husbandry for the acquisition of this breed of goats, imported from the East under the auspices of their government, by the indefalisable courage and zeal of M. Jaubert, who encountered every fatigue and danger to enrich his country with these va?aable animals, aided by the patriotism of M. Ternaux, who first planned this importation, and furnished funds for executin«» it at his own expense and responsibility. He placed a portion of the flock brought by M. Jaubert, at his villa of Saint Ouen, near Paris, where the climate seemed to be'' very favorable to ihem, since for several successive years after theur introduction M. Ternaux was enabled to sell a great number of both male and female goals. The quantity of fine fleece or down aflforded by each animal annually, is from a pound and a half to two pounds. « « , • , r J «v The wool imported into Europe comes by the way of Casan, the capital ol a gdvem- ment of the Russian empire upon the eastern bank of the Wolga; it has naturally a grayish color, but is easily bleached. Its price a few years back at Paris was 17 francs per kilogramme ; that is, about 6 shillings the pound avoirdupois. The waste in picking, carding,''and spinning, amounts to about one third of its weight. The mills for spinning Cachemere wool have multiplied very much of late years m France as appears from the premiums distributed at the exposition of 1834, and the prices of the yarn have fallen from 25 to 30 per cent, notwithstanding their improved fineness and quality. There is a fabric made with a mixture of Cachemere down and spun silk which is becoming very general. One of the manufacturers, M. Hmdenlang, exhibited samples of Cachemere cloth woven with yarn so fine as No. 130 for warp, and No. 228 for weft. , ^ ^ ^ ■ r ^ Messrs. Pollino, brothers, of Paris, produced an assortment of Cachemere pieces Irom 22 to 100 francs the yard, dyed of every fancy shade. Their establishment at Ferte-Ber- nard occupies 700 operatives, with an hydraulic wheel of 60 horse power. The oriental Cashmere shawls are woven by processes extremely slow and consequently costly whence their prices are very high. They are still sold in Paris at from 4,000 to 10 000 francs a piece ; and from 100 to 400 pounds sterling in London. It became necessary, therefore, either to rest satisfied with work which should have merely a surface appearance or contrive economical methods of weaving, to produce the real Cachemere style with inuch less labor. By the aid of the draw-loom, and still better of the Jacquard loom M. Ternaux first succeeded in weaving Cachemere shawls perfectly similar to the oriental in external aspect, which became fashionable under the name of French Cache- mere. But to construct shawls altos;ether identical on both sides with the eastern, was a more diflicult task, which was accomplished only at a later period by M. Bauson of In both modes of manufacture, the piece is mounted by reeding-in the warp for the different leaves of the heddles, as is commonly practised for warps in the Jacquard looms. The weaving of imitation shawls is executed, as usual, by as many shuttles »« there are colors in the design, and which are thrown across the warp in the order eslablisheci by 384 CASK. CASSAVA. 385 '/mi the neder. The greater numbei of these weft yams being introduced only at intervals into the web, when the composition of the pattern requires it, they remain floating loose at the back of the piece, and are cut afterwards, without affecting in the least the quality of the texture ; but there is a considerable waste of stuff in the weaving, which is worked up into carpets. The weaving of the imitation of real Cachemere shawls is different from the above. The yarns intended to form the weft are not only equal in number to that of the colors of the pattern to be imitated, but besides this, as many little shuttles or pirns (like those used by embroiderers) are filled with these yarns, as there are to be colors repeated in the breadth of the piece ; which renders their number considerable when the pattern is somewhat complicated and loaded with colors. Each of these small bobbins or shuttles passes throuirh only that portion of the flower in which the color of its yarn is to appear, and Slops at the one side and the other of the cloth exactly at its limit ; it then returns upon itself after having crossed the thread of the adjoinins shuttle. From this recipro- cal intertexture of all the yarns of the shuttles, it results, that although the weft is composed of a great many different threads, they no less constitute a continuous line in the whole breadth of the web, upon which the lay or batteu acts in the ordinary way We see, therefore, that the whole art of manufacturing this Cachemere cloth consists in avoiding the confusion of the shuttles, and in not striking up the lay till all have fulfilled their function. The labor does not exceed the strength of a woman, even though she has to direct the loom and work the treddles. Seated on her bench at the end opposite to the middle of the beam, she has for aids in weaving shawls from 45 to 52 inches wide, two girl apprentices, whom she directs and instructs in their tasks. About four hundred days of work are required for a Cachemere shawl of that breadth. For the construction of the loom, see Jacquard. In the oriental process, all the figures in relief are made simply with a slender pirn without the shuttle used in European weaving. By the Indians the flower and its ground are made with the pirn, by means of an intertwisting, which renders them in some measure independent of the warp. In the Lyons imitation of this style, the leaves of the heddles lift the yarns of the warp, the needles embroider as in lappet weaving, and the flower is united to the warp by the weft thrown across the piece. Thus a great deal of labor is saved, the eye is pleased with an illusion of the loom, and the shawls cost little more than those made by the common fly shuttle. Considered in reference to their materials, the French shawls present three distinct classes, which characterize the three fabrics of Paris, Lyons, and Nimes. Paris manufactures the French Cachemere, properly so called, of which both th* warp and the weft are the yarn of pure Cachemere down. This web represents with fidelity the figures ami the shades of color of the Indian shawl, which it copies ; the dectption would be complete if the reverse of the piece did not show the cut ends. The Hindoo shawl, also woven at Paris, has its warp in spun silk, which reduces its price without impairing its beauty much. LyonsJ however, has made the greatest progress in the manufacture of shawls. It ex- cels particularly in the texture of its Thibet shawls, the weft of which is yarn spun with a mixture of wool and spun silk. . , «, Nimes is remarkable for the low price of its shawls, in which spun silk, Thibet down, and cotton, are all worked up together. The value of shawls exported from France in the following years was— 1831. 1832. 1833. Woollen ------ Cachemere down - - Spun silk Frnncs. 1,863,147 433,410 401,856 Francs. 2,070,926 655,200 351,152 Francs. 4,319,601 609,900 408,824 I 1 ii It appears that M. J. Girard at Sevres, near Paris, has succeeded best m producing Cachemere shawls equal in stuff and style of work to the oriental, and tt a lower price. They have this advantage over the Indian shawls, that they are woven without seams, in a single piece, and exhibit all the variety and the raised effect of the eastern colors. Women and children alone are employed in his factor^'. CASK (Tonneau, Fr. ; Fass, Germ.), manufacture of by mechanical power. Mr. Samuel Brown obtained a patent in November, 1825, for certain improvements in machinery for making casks, which seems to be ingenious and worthy of record. His mechanism consists in the first place of a circular saw attached to a bench, with a sliding rest upon which rest each piece of wood intended to form a stave of a cask is fixed ;. and' the rest being then slidden forward in a curved direction, by the assistance of an adjustable guide, brings the piece of wood against the edge of the rotatory saw, and causes it to be cut into the curved shape required for the edge of the stave. The second feature is an apparatus with cutters attached to a standard, and traversing round with their earner upon a centre, by means of which the upper and lower edges of the cask are cut round and grooved, called chining, for the purpose of receiving the heads. Thirdly, an apparatus not very dissimilar to the last, by which the straight pieces of wood designed for the heads of the cask are held together, and cut to the circular figiire required, and also the bevelled edges produced. And fourthly, a machine in which the cask is made to revolve upon an axis, and a cutting tool to traverse for the purpose of shaving the external part of the cask, and bringing it to a smooth surface. . . .. • The pieces of wood intended to form the staves of the cask, having been cut to their required length and breadth, are placed upon the slide-rest of the first mentioned machine, and confined by cramps ; and the guide, which is a flexible bar, having been previoiMly bent to the intended curve of the stave and fixe<} in that form, the rest is then slidden forward upon the bench by the hand of the workman, which as it advances (moving in a curved direction) brings the piece of wood against the edge of the revolving circular saw, by which it is cut to the curved shape desired. The guide is a long bar held by a series of movable blocks fitted to the bench by screws, and is bent to any desired curve by shifting the screws : the edge of the slide-rests which holds the piece of wood about to be cut, runs against the long guide bar, and of consequence is conducted in a corresponding curved course. The circular saw receive* a rapid rotatory motion by means of a band or rigger from any first mover ; and the piece of wood may be shifted laterally by means of racks and pinions on the side-rest, by the workman turning a handle, which is occasionally necessary in order to bring the piece of wood up to, or away from, the saw. , , , , . j -.v The necessary number of staves being provided, they are then set round within a confining hoop at bottom, and brought into the form of a cask in the usual way, and braced by temporary hoops. The barrel part of the cask being thus prepared, in order to effect the chining, it is placed in a frame upon a platform, which is raised up by a treddle lever, that the end of the barrel may meet the cutters in a sort of lathe above : the cutters are then made to traverse round within the head of the barrel, and, as they pro- ceed, occasionally to expand, by which means the bevels and grooves are cui on the upper edge of the barrel, which is caUed chiAing. The barrel being now reversed, the same apparatus is brought to act against the other end, which becomes chined in like manner. , » ♦ • v* The pieces of wood intended to form the heads of the cask are now to be cut straight by a circular saw in a machine, similar to the first described ; but in the present instance the slide-rest is to move forward in a straisht course. After their straight edges are thus produced, they are to be placed side by side, and confined, when a scribing cutter is made to traverse round, and cut the pieces collectively into the circular form desired for heading the cask. . . . , ... The cask having now been made up, and headed by hand as usual, it is p*ace(l between centres or upon an axle in a machine, and turned round by a rigger or band with a shaving cutter, sliding along a bar above it, which cutter, being made to advance and recede as it slides along, shaves the outer part of the cask to a smooth surface. CASSAVA. Cassava bread, coiiaque, ^-c, are different names given to the starch of the root of the Manioc {Jatropha Manihot, Linn.), prepared in the following manuer in the West Indies, the tropical regions of America, and upon the African coast. The tree belongs to the natural family of the euphorbiacea. The roots are washed, and reduced to a pulp by means of a rasp or grater. The pulp is put into coarse strong canvass bags, and thus submitted to the action of a powerful press by which it parts with most of its noxious juice (used by the Indians for poisoning the barbs of their arrows.) As the active principle of this juice is volatile, it is easily dissipated by bakin? the squeezed cakes of pulp upon a plate of hot iron. Fifty pounds of the fresh juice, when distilled, afford, at first, three ounces of a poisonous water, pos- sessing an intolerably ofiensive smell; of which, 35 drops bemg administered to a slave convicted of the crime of poisoning, caused his death in the course of six minutes, amid horrible convulsions.* . ,. v v The pulp dried in the manner above described concretes into lumps, which become hard and friable as they cool. They are then broken into pieces, and laid out in the sun to dry In this state they afford a wholesome nutriment, and are habitually used as such by the negroes, as also by many white people. These cakes constitute the only pro- visions laid in by the natives, in their voyages upon the Amazons. Boiled in water with a little beef or mutton they form a kind of soup similar to that of rice. The cassava cakes sent to Europe (which I have eaten with pleasure) are composed almost entirely of starch, along with a few fibres of the ligneous matter. It may be purified by diffusion through warm water, passing the milky mixture through a linen doth, evaporating the strained liquid over the fire, with constant agitation. Ihe starch ♦ Memoir of Dr. Fermin, communicated to the Academy of Berlin concerning experiment! »ad« at Cay- enn*" upon ths juice of the Manioc. Vou L 3D I 386 Casting of metals. dissolved by the heat, thickens as the water evaporates, but on being stirred, it becomes granulated, and must be finally dried in a proper stove. Its speci6c gravity is 1-530 — that of the other species of starch. The product obtained by this treatment is known in commerce under the name of /o- pioca ; and being starch very nearly pure, is oAen prescribed by physicians as an aliment of easy digestion. A tolerably good imitation of it is made by heating, stirring, and drying potato starch in a similar way. cry v v The expressed juice of the root of manioc contains in suspension a very fine fecula, whicn it deposiies slowly upon the bottom of the vessels. When freed by decantation from the su- pernatant liquor, washed several times and dried, it forms a beautiful starch, which creaks on pressure with the fingers. It is called cipipa, in French Guyana; it is employed for many delicate articles of cookery, especially pastry, as also for hair powder, starching linen, &c. Cassava flour, as imported, may be distinguished from arrow-root and other kmds of starch, by the appearance of its particles viewed in a microscope. They are spherical, all about 1-lOOOth of an inch in diameter, and associated in groups ; those of potato starch are irregular ellipsoids, varying in size from l-300th to l-3000th of an inch; those of arrow-root have the same shape nearly, but vary in size from l-500th to l-800th of an inch; those of wheat are separate spheres 1-lOOOth of an inch. CASSIS, the black currant (jibes nigra, Linn.), which was formerly celebrated for its medicinal properties with very little reason. The only technical use to which it '^ now applied is in preparing the agreeable limieur called ratafia, by the following French recipe : — Stone, and crush three pounds of black currants, adding to the magma one drachm of cloves, two of cinnamon, four quarts of spirit of wine, at 98° Baum6 (see Areometre of Baume), and 2i pounds of sugar. Put the mixture into a bottle which is to be well corked ; let it digest for a fortnight, shaking the bottle once daily during the first eight days; then strain through a linen cloth, and finally pass through filtering paper. CASSIUS, purple powder of. A prep&ration used in the arts as a colour, chiefly for stained glass and porcelain. It is also employed in medicine by some French physicians, and has been prepared by the following prescription : — 10 parts of acid chloride of gold are dissolved m 2000 parts of water. In another vessel, 10 parts of pure tin are dis- solved in 10 parts of nitric acid mixed with 20 parts of hydrochloric, and this solution is diluted with 1000 parts of distilled water. The solution of tin is added by degrees to that of the acid chloride of gold, as long as any precipitate results which is allowed to subside ; it is then washed, filtered, and then dried at a very gentle heat. The tin salt above used contains both the protoxide and binoxide in certain proportions. The double compound of chloride of tin with sal ammoniac, called the ^link salt of tin, is the preferable form ; as it is not altered by the atmosphere, is of definite composition, and when boiled with metallic tin it takes up just so much as will form the protochlo- ride; 100 parts of pink salt require for this purpose lO"? parts of metallic tin. 1-34 gr. of gold are to be dissolved in aqua regia, without excess of the solvent, and this solution is to be diluted with 480 gr. of water. Then 10 gr. of the pink salt mixed with 1*07 gr. of tin filings, and 40 gr. of water, are to be exposed to a boiling heat till the metal is dissolved. 140 gr. of water are now to be poured upon that com- pound, and the resulting solution is to be gradually added to the gold liquor (slightly warmed) till no more precipitate forms. Tliis when washed and dried is of a brown colour, and weighs 4-92 grs. The above method of preparing the solution of the ses- quioxide of tin seems to be the best hitherto prescribed. CASTING OF METALS. (See Founding.) Casts from elastic matdds.— Being much engaged in taking easts from anatomical preparations, Mr. Douglas Fox, Surgeon, Derby, found great difficulty, principally with hard bodies, which, when undercut, or having considerable overlaps, did not admit of the removal of moulds of the ordinary kind, except with injury. These difficulties suggested to him the use of elastic moulds, which, giving way as they were withdrawn from complicated parts, would return to their proper shape ; and he ultimately succeeded in making such moulds of glue which not only reUeved him from all his difficulties, but were attended with great advantages, in consequence of the small number of pieces into which it was necessary to divide the mould. The body to be moulded, previously oiled, must be secured one inch above the sur- face of a board, and then surrounded by a wall of clay, about an inch distant from its sides. The clay must also extend rath'er higher than the contained body : into this, warm melted glue, as thick as possible so that it will run, is to be poured, so as to completely cover the body to be moulded ; the glue is to remain till cold, when it will have set into an elastic mass, just such as is required. Having removed the clay, the glue is to be cut into as many pieces as may be ne- ceaeary for its removal, either by a sharp-pointed knife, or by having placed threads in CASTOR OIL. SBt the requisite situations of the body to be moulded, which may be drawn away when the glue is set, so as to cut it out in any direction. The portions of the glue mould having been removed from the original, are to be placed together and bound round by tape. In some instances it is well to run small wooden pegs through the portions of glue, so as to keep them exactly in their proper positions. If the mould be of considerable size, it is better to let it be bound with moderate tightness upon a board to prevent it bending whilst in use ; having done as above described, the plaster of Paris, as in com- mon casting, is to be poured into the mould, and left to set In many instances wax may also be cast in glue, if it is not poured in whilst too hot ; as the wax cools so rapidly when applied to the cold glue, that the sharpness of the impression is not injured. Glue has been described as succeding well where the elastic mould is alone applica- ble; but many modifications are admissible. When the moulds are not used soon after being made, treacle should be previously mixed with the glue (as employed by printers) to prevent it becoming hard. The description thus given is with reference to moulding those bodies which cannot be so done by any other than an elastic mould ; but glue moulds will be found greatly to facilitate casting in many departments, as a mould may be frequently taken by this method in two or three pieces, which would, on any other principle, require many. CAST-IRON SCOURING. Cast-iron surfaces are said to be easily scoured by adding a little of any kind of organic matter, such as glycerine, steariue, napthaline, creo- sote to dilute sulphuric acid ; zinc and brass yield to the same method, with great economy of labour, time and material, CASTOR. (Eng. and Fr. ; Biber, Germ.) The castor is an amphibious quad> ruped, inhabiting North America ; also found in small numbers in the islands of the Rhone. In the arts, the skin of this animal is employed either as a fur or as affording the silky hair called beaver, with which the best hats are covered. Beaver skins, which form a very considerable article of trade, are divided into 3 sorts : 1. The fresh beaver skins from castors, killed in winter before shedding their hair; these are most in re- quest among the furriers, as being the most beautiful. 2. The dry or lean beavers are the skins of the animals killed during the moulting season ; they are not much esteemed, as the skin is rather bare. 3. The fat castors : these are the skins of the first sort, which have been worn for some time upon the persons of the savages, and have got imbued with their sweat. The last are principally used in the hat manufacture. In France, the marine otter has been for many years substituted in the place of the castor oi beaver. CASTOR or CASTOREUM. This name is given to a secretion of the castor?, eoatained in pear-shaped cellular organic sacs, placed near the genital organs of both ihe male and female animals. It is a substance analogous to civet and musk, of a consist- ence similar to thick honey. It has a bitter acrid taste ; a powerful, penetrating, fetid, and very volatile smell ; but, when dried, it becomes inodorous. Several chemists, and in particular Bouillon Lasrrange, Laugier, and Hildebrandt, have examined castor, and found it to be composed of a resin, a fatty substance, a volatile oil, an extractive matter, benzoic acid, and some salts. The mode of preparing it is very simple. The sacs are cut off from the castors when they are killed, and are dried to prevent the skin being aflTected by the weather. In this state, the interior sub>tance is solid, of a dark color, and a faint smell ; it softens with heat, and becomes brittle by cold. Its fracture betrays fragments of membranes, indi- cating its organic structure. When chewed, it adheres to the teeth somewhat like wax; it has a bitter, slightly aciid, and nauseous taste. The castor bags, as imported, are often joined in pairs by a kind of ligature. Some times the substance which constitutes their value is sophisticated ; a portion of the cas- toreum being extracted, and replaced by lead, clay, gums, or some other foreign matters. This fraud may be easily detected, even when it exists in a small degree, by the absence of the membranous partitions in the interior of the bags, as well as by the altered smell and taste. The use of castoreum in medicine is considerable, especially in nej vous and spasmodic diseases, and it is often advantageously combined with opium. CASTORINE. A chemical principle lately discovered to the amount of a few parts per cent, in Castoreum. CASTOR OIL. The expressed oil of the seeds of the Palma Christi, or Ricinus communis, a native tree of the West Indies and South America ; but which has been cul- tivated in France, Italy, and Spain. Bussy and Lecanu discovered in it 3 species of fatty matters, obtained partly by saponification, and partly by dry distillation — the mar- garitic, ricinic, and elaiodic acids. None of these has been separately applied to any use in the arts. 8D2 I ' 388 CATECHU. CATGUT. 389 ilffil H The quantity of castor oil imported in 1835 into the United Kingdom was 1,109,307 lbs. ; retained for home consumption, 670,205 lbs. See Oils. CATECHU, absurdly called Terra Japonica, is an extract made from the wood of the tree mimosa catechu, which grows in Bombay, Bengal, and other parts of India. It is prepared by boiling the chips of the interior of the trunk in water, evaporating the solution to the consistence of sirup over the fire, and then exposing it in the sun to harden. It occurs in flat rough cakes, and under two forms. The first, or the Bombay, is of uniform texture, of a dark red color, and of specific gravity 1*39. The second is more friable and less solid. It has a chocolate color, and is marked inside with red streaks. Its specific gravity is 1*28. According to Sir H. Davy, these two species are composed as follows : — • Tannin ------- Extractive - - - . - Mucilage - - - - - Insoluble matters, sand and lime Bombay. Bengal. | 54-5 34-0 6-5 5 48-5 36-5 8 7 100-0 100-0 Areka nuts are also found to yield catechu ; for which purpose they are cut into pieces watered in an earthen pot with solution of nitre, and have a little of the bark of a species of mimosa added to them. The liquor is then boiled with the nuts, and afl^ords mti inspissated decoction. Good catechu is a brittle, compact solid, of a dull fracture. It has no smell, but a Tcry astringent taste. Water dissolves the whole of it, except the earthy matter, which IS probably added during its preparation. Alcohol dissolves its tannin and extractive. The latter may be oxydized, and thus rendered insoluble in alcohol, by dissolving the catechu in water, exposing it for some time to a boiling heat, and evaporating to dryness. The tannin of catechu differs from that of galls, in being soluble in alcohol, and more soluble in water. It precipitates iron of an olive color, and gelatin in a mass which gradually becomes brown. It has been long employed in India for tanning j^ins, where it is said to effect this object in five days. I have seen a piece of sole leather completely tanned by it in this country in ten days, the ox-hide having been made into a bag, with the hair outside, and kept filled with the solution of catechu. In India it has also been used to give a brown dye to cotton ^oods, and of late ynars it has been extensively introduced into the calico prmi works of Europe. The salts of copper with sal ammoniac cause it to give a bronze color, which is very fast ; the proto-muriate of tin, a brownish yellow ; the per-chloride of tin, with the addition of nitrate of copper, a deep bronze hue ; acetate of alumina alone, a reddish brown, and, with nitrate of copper, a reddish olive gray ; nitrate of iron, a dark brown gray. For dyeing a golden coffee brown, it has entirely superseded mad- der; one pound of it being equivalent to six pounds of this root. A solution of one part of catechu in ten parts of water, which is reddish brown, exhibits the following results : with — . A brightened shade. - A darkened shade. . Olive blown precipitate. - Olive green do. . Yellowish brown. . A brightening of the liquor. - Olive green precipitate. . Yellowish brown do. Acids Alkalis - - - Proto-sulphate of iron Per-sulphjite of iron Sulphate of copper - Alum . - - Per-nitrate of iron - Nitrate of copper - Nitrate of lead Proto-nitrate of mercury Muriate of alumina Muriate of tin Per-chloride of tin - Corrosive sublimate Acetate of alumina - Acetate of copper - Acetate of lead Bichromate of potash Salmon do. Milk-coffee do. Brown-yellow. Do. do. Do. darker. Light chocolate do. Brightening of the liquor. Copious brown precipitate Salmon colored do. - Copious brown do. Pure tannin may be obtained from catechu, by treating it with sulphuric acid and car* bonate of lead ; but this process has no manufacturing application. CATGUT (Corde a boyau, Fr. ; i>armsaite, Germ.), the name absurdly enough given to cords made of the twisted intestines of the sheep. The guts being taken while warm out of the body of the animal, are to be cleared of feculent matter, freed from any ad- hering fat, and washed in a tub of water. The small ends of all the intestmes ore next to be tied together, and laid on the edge of the tub, while the body of them is left to steep in some water, frequently changed, during two^lays, in order to loosen the peritoneal and mucous membranes. The bundle of intestines is then laid upon a sloping table which overhangs the tub, and their surface is scraped with the back of a knife, to try if the external membrane will come away freely in breadths of about half the circumference. This substance is called by the French manufacturers filandre, and the process filer. If we attempt to remove it by beginning at the large end of the intestine, we shall not succeed. This filandre is employed as thread to sew intestines, and to make the cords of rackets and battledoors. The flayed guts are put again into fresh water, and, after steeping a night, are taken out and scraped clean next day, on the wooden bench with the rounded back of a knife. This is called curing (he gut. The large ends are now cut off, and sold to the pork-butchers. The intestines are again steeped for a night in fresh water, and the following day in an alkaline lixivium made by adding 4 ounces of potash, and as much pearl-ash, to a pail of water containing about 3 or 4 imperial gallons. This ley is poured in successive quantities upon the intestines, and poured off again, after 2 or 3 hours, till they be purified. They are now drawn several times through an open brass thimble, and pressed against it with the nail, in or- der to smooth and equalize their surface. They are lastly sorted, according to their sizes, to suit different purposes. . Whip-cord is made from the above intestines, which are sewed together endwise by the filandre, each junction being cut aslant, so as to make it strong and smooth. The cord is put inio the frame, and each end is twisted separately ; for whip-cord is seldom made out of two guts twisted together. When twisted, it is to be sulphured (see Sulphuring) once or twice. It may also be dyed black with common ink, pink with red ink, which the sulphurous acid changes to pink, and green with a green dye which the color dealers sell for the purpose. The guts take the dyes readily. After being well smoothed, the cord is to be dried, and coiled up for sale. . Hatters' cords for bowstrings. — The longest and largest intestines of sheep, after being properly treated with the potash, are to be twisted 4, 6, 8, 10, or 12 together, according to the intended size of the cord, which is usually made from 15 to 25 feet long. This cord must be free from seams and knots. When half dry, it must be exposed twice to the fumes of burning sulphur ; and, after each operation, it is to be well stretched and imoothed : it should be finally dried in a state of tension. Clockmaker's cord. — This cord should be extremely thin, and be therefore made from ▼wy small intestines, or from intestines slit up in their length by a knife fitted for tha purpose; being a kind of lancet surmounted with a ball of lead or wood. The wet gut is strained over the ball which guides the knife, and the two sections fall down into a vessel placed beneath. Each hand pulls a section. Clockmakers also make use of stronger cords made of 2 or more guts twisted tc^ether. Fiddle and harp s/rings. —These require the greatest care and dexterity on the part of the workmen. The treble strings are peculiarly diflScult to make, and are best made at Naples, probably because thew sheep, from their small size and leanness, afford the best raw material. The first scraping of the guts intended for fiddle-strings must be very carefully performed ; and the alkaline ley's, being clarified with a little alum, are added, in a progressively stronger state from day to day, during 4 or 5 days, till the guts be well bleached and swollen. They must then be passed through the thimble, and again cleansed with the lixivium; after which they are washed, spun, or twisted and sulphured during two hours. They are finally polished by friction, and dried. Sometimes they are sulphured twice or thrice before being dried, and are polished between norse-hair cords. It has been long a subject of complaint, as well as a serious inconvenience to mu- sicians that catgut strings cannot be made in England of the same goodness and strength as those imported from Italy. These are made of the peritoneal covering of the in- testines of the sheep ; and, in this country, they are manufactured at Whitechapei, and probably elsewhere in considerable quantity ; the consumption of them for harps, as well as for the instruments of the violin family, being very great. Their chief fault is weakness ; whence it is diflicult to bring the smaller ones, required for the higher notes, to concert' pitch ; maintaining at the same time, in their form and construction, that tenuity or smallness of diameter, which is required to produce a brilliant and clear tone. The inconvenience arising from their breaking when in use, and the expense in the case of harps, where so many are required, are such as to render it highly desirable to improve a manufacture which, to many individuals may, however, appear sutficienay con- temptible. 390 CEMENTS. CEMENTS. 391 It IS well known to physioloslsts, that Ihe membranes of lean animals are far more tough than of those animals which are fat or in high condition ; and there is no reason to doubt that the superiority of the Italian strings arises from the state of the sheep in that country. In London, where no lean animals are slaughtered, and where, indeed, an extravagant and useless degree of fattening, at least for the purpose of food, is given to sheep in particular, it is easv to comprehend why their membranes can never afford a material of the requisite tenacity. It is less easy to suggest an adequate remedy ; but a knowledge of the general principle, should this notice meet the eyes of those interested in the subject, may at least serve the purpose of diminishing the evil and improving the ma- nufacture, by inducing them to choose in the market the ofl'al of such carcasses as appear least overburdened with fat. It is probable that such a manufacture might be advan- tageously established in those parts of the country where the fashion has not, as in London, led to the use of meat so much overfed ; and it is equally likely, that in the choice of sheep for this purpose, advantage would arise from usins the Welch, the High- land, or the Southdown breeds, in preference to those which, like the Lincoln, are prone to excessive accumulations of fat. It is equally probable, that sheep dying of some of t\e diseases accompanied by emaciation, would be peculiarly adapted to this pnrf/>se. That these suggestions are not merely speculative is proved by comparing the strength of the membranes in question, or that of the other membranous parts, in the unfaltened Highland sheep, with that of those found in the London markets. CATHARTINE. The name proposed by MM. Feneulle and Lassaigne for a chemi- cal principle, which they suppose to be the active constituent of senna. CAUSTIC. Any chemical substance corrosive of the skin and flesh j as potash, called common caustic, and nitrate of silver, called lunar caustic, by surgeons. CAVIAR. The salted roe of certain species of fish, especially the sturgeon. This product forms a considerable article of trade, being exported annually from the town of Astrachan alone, upon the shores of the Caspian sea, to the amount of several hundred tons. The Italians first introduced it into Eastern Europe from Constantinople, under the name of caviale. Russia has now monopolized this branch of commerce. It is pre- pared in the following manner : — The female sturgeon is gutted ; the roe is separated from the other parts, and cleaned bypassing it through a very fine searce, by rubbing it into a pulp between the hands; this is afterwards thrown into tubs, with the addition of a considerable quantity of salt ; the whole is then well stirred, and set aside in a warm apartment. There is another sort of caviar, the compressed, in which the roe, after having been cured in strong brine^ is dried in the sun, then put into a task, and subjected to strong pressure. CAWK. The English miner's name for sulphate of baryta, or heavy spar, CEDRA {Cedrat, Fr.) is the fruit of a species of orange, citron, or lemon, a tree which bears the same name. Its peel is very thick, and covered with an epidermis which en- closes a very^ fragrant and highly prized essential oil. The preserves flavored with it ■re very agreeable. The citrons are cut into quarters for the dry comfits, but are put whole into the liquid ones. The liquorist-perfumer makes wit/i the peel of the cedra an ex- cellent liqueur ; for which purpose, he plucks them beft re they arc quite ripe ; grate? down the peel into a little brandy, or cirts them into slices, and infuses these in the spirits. This infusion is distilled for making perfume; but the flavor is better wher. the infusion itself is used. See Essences, Liquokist, Perfumery. CELESTINE. Native sulphate of strontia, found abundantly near Bristol, m the red marl formation. It is decomposed, by ignition with charcoal, into sulphuret of strontia, which is converted into nitrate by saturation with nitric acid, evaporation, and crystallization. This nitrate is employed for the production of the red light in theatrical fire-works. CEMENTATION. A chemical process, which consists in imbedding a solid body in a pulverulent matter, and exposing both to ignition in an earthen or metallic case. In this way, iron is cemented with charcoal to form steel, and bottle glass with gypsum powder, or sand, to form Reaumur's porcelain. CEMENTS. {Cimentsy Fr. ; Cdmente, Kitte, Germ.) Si^bstances capable of taking the liquid form, and of being in that stale applied between the surfaces of two bodies, po as to unite them by solidifying. They may be divided into two classes, those which are applieo through the agency of a liquid menstruum, such as water, alcohol, or oil, and those which are applied by fusion with heat. The diamond cement for uniting broken pieces of china, glass, &c., which is sold as a secret at an absurdly dear price, is composed of isinglass soaked in water till it becomes soft, and then dissolved in proof spirit, to which a little gum resin, ammoniac, or galba- num, and resin mastic are added, each previously dissolved in a minimum of alcohol. When to be applied, it must be gently heated to liquefy it; and it should be kept for use in a well-corked vial. A glass stopper would be apt to fix so as not to be remove able. This is the cement employed by the Armenian jewellers in Turkey for glue- ing the ornamental stones to trinkets of various kinds. When well made it lesists moisture. - . - *. j Shellac dissolved in alcohol, or in a solution of borax, forms a pretty good cemenu White of esg alone, or mixed with finely sifted quicklime, will answer for uniting objects which are not exposed to moisture. The latter combination is very strong, an^. is much employed for joining pieces of spar and marble ornaments. A similar com- position is used by copper-smiths to secure the edges and rivets of boilers ; only bullock's blood is the albuminous matter used instead of white of egg. Another cement in which an analogous substance, the curd or caseum of milk is employed, is made by boiling slices of skim-milk cheeses into a gluey consistence in a great quantity of water, and then incorporating it with quicklime on a slab with a muller, or in a marble mortar. When this compound is applied warm to broken edges of stoneware, it unites them very firmly after it is cold. A cement which gradually indurates to a stony consistence may be made by mixing 20 parts of clean river sand, two of litharge, and one of quicklime, into a thin putty with linseed oil. The quicklime may be replaced with litharge. When this cement is applied to mend broken pieces of stone, as steps of stairs, it acquires after some time m stony hardness. A similar composition has been applied to coat over brick walls, under the name of mastic. . ■, j j The iron-rust cement is made of from 50 to 100 parts of iron borings, pounded and lifted, mixed with one part of sal-ammoniac, and when it is to be applied moistened with as much water as will give it a pasty consistency. Formerly flowers of sulphur were used, and much more sal-ammoniac in making this cement, but with decided disadvantage, as the union is effected by the oxydizement, consequent expansion and solidification of the iron powder, and any heterogeneous matter obstructs the effect. The best proportion of sal-ammoniac is, I believe, one per cent, of the iron borings. Another composition of the same kind is made by mixing 4 parts of fine borings or filings of iron, 2 parts of potter's clay and 1 part of pounded potsherds, and making them into a paste with salt ana water. When this cement is allowed to concrete slowly on iron joints, it becomes very For making architectural ornaments in relief, a moulding composition is formed of chalk, glue, and paper paste. Even statues have been made with it, the paper aiding the cohesion of the mass. j /• j v v . Mastics of a resinous or bituminous nature which must be softened or fused by heal %re the following : — ,. .^ , , ^ . , j • j v - Mr. S. Valley's consists of sixteen parts of whiting sifted and thoroughly dried by t red heat, adding when cold a melted mixture of 16 parts of black rosin and 1 of bees'-wax, and stirring well during the cooling. ^ - ■, e Mr. Singer's electrical and chemical apparatus cement consists of 5 lbs. of rosin« 1 of hees'-wax, 1 of red ochre, and two table-spoonsful of Paris plaster, all melted together. A cheaper one for cementing voltaic plates into wooden troughs is made with 6 pounds of rosin, 1 pound of red ochre, | of a pound of plaster of Paris, and ^ of a pound of lin- seed oil. The ochre and the plaster of Paris should be calcined beforehand, and added to the other ingredients in their melted slate. The thinner the stratum of cement that is interposed, the stronger, generally speaking, is the junction. Boiled linseed oil and red lead mixed together into a putty are often used by copper- smiths and engineers, to secure joints. The washers of leather or cloth are smeared with this mixture in a pasty state. The resin mastic alone is sometimes used by jewellers to cement by heat cameos of white enamel or colored glass to a real stone, as a ground to produce the appearance of an onyx. Mastic is likewise used to cement false backs or doublets to stones, to alter their hue. Melted brimstone, either alone, or mixed with rosin and brick dust, forms a tolerably good and very cheap cement. Plumber's cement consists of black rosin one part, brick dust two parts, well incorpo- rated by a melting heat. The cement of dihl for coating the fronts of buildings consists of linseed oil, rendered dry by boiling with litharge, and mixed with porcelain clay in fine powder, to give it the consistence of stiff mortar. Pipe-clay would answer equally well if well dried, and any color might be given with ground bricks, or pottery. A little oil of turpentine to thin this cement aids its cohesion upon stone, brick, or wood. It has been applied to sheets of wire cloth, and in this state laid upon terraces, in order to make them water tight; but it is little less expensive than lead. j u u j The bituminous or black cement for bottle-corks consists of pitch hardened by the ad- dition of rosin and brick-dust. - - a -^ In certain localities where a limestone impregnated with bitumen occurs, it is dried. : i f|i 392 CEMENTS. li II ground, sifted, and then mixed with about its own weight of melted pitch, either mineral, vegetable, or that of coal tar. When this mixture is getting semifluid, it may be moulded into large slabs or tiles in wooden frames lined with sheet iron, previously smeared over with common lime mortar, in order to prevent adhesion to the moulds, which, being m moveable pieces, are easily dismounted so as to turn out the cake of artificial bituminous stone. This cement is manufactured upon a great scale in many places, and used for makins: Italian terraces, covering the floors of balconies, flat roofs, water reservoirs, water conduits, &c. AVhen laid down, the joints must be well run together with hot irons. The floor of the terrace should be previously covered with a layer of Paris plaster or common mortar, nearly an inch thick, with a regular slope of one inch to the yard. Such bitumin- ous cement weighs 144 pounds the cubic foot ; or a foot of square surface, one inch thick, weighs 12 pounds. Sometimes a second layer of these slabs or tiles is applied oyer the first, with the precaution of making the seams or joints of the upper correspond with the middle of the under ones. Occasionally a bottom bed, of coarse cloth or gray paper, is applied. The larger the slabs are made, as far as they can be conveniently transported and laid down, so much the better. For hydraulic cements, see Mortar. An excellent cement for resisting moisture is made by incorporating thoroughly eight parts of melted glue, of the consistence used by carpenters, with four parts of linseed oil, boiled into varnish with litharge. This cement hardens in about forty-eight hours, and renders the joints of wooden cisterns and casks air and water tight A compound of glue with one-fourth its weight of Venice turpentine, made as above, serves to cement glass, metal and wood, to one another. Fresh-made cheese curd, and old skim-milk cheese, boiled in water to a slimy consistence, dissolved in a solution of bicarbonate of potash, are said to form a good cement for glass and porcelain. Tlie gluten of wheat, well prepared, is also a good cement White of eggs, with flour and water well-mixed, and smeared over linen cloth, forms a ready lute for steam joints in small apparatus. -, ^ ^ ^ ^ *. i r White lead ground upon a slab with linseed oil varnish, and kept out of contact of air, affords a cement capable of repairing fractured bodies of all kinds. It requires a few weeks to harden. When stone or iron are to be cemented together, a compound of equal parts of sulphur with pitch answers very well. Mr. Joseph Gibbs, a practical civil engineer of eminence, obtained a patent in May, 1850 for improvements in artificial stone, mortar and cements, and in the modes of manufacturing the same, of which the following abstract is worthy of attention "The several descriptions of Roman cement are made from the septaria of either Harwich or Sheppey or from the septaria of the lias formation, or from beds of cement stone found in the upper division of the lias formation, or in the shale beds^ of the Kimmeridge clay. All these stones, when manufactured, produce a material oi a dark brown colour, unfit for incrusting buildings so as to imitate stone, unless they are either coloured by washes, or by painting. N ow, amongst the advantages to be obtained from the cements and mortars I have invented is this, that every description of freestone may be exactly imitated without any wash or painting whatsoever being applied. "Again the cement called Portland cement is made by mixing clay and chalk, or river mud and chalk, in such proportions together that the combined materials may contain about the same proportions of lime, silica, and alumina, as are found m cements. These materials are ground together in water to a great degree of faneness. After subsidence, and also after obtaining the proper consistency, the pasty materials are dned in kilns, or otherwise, and afterwards burned like ordinary cements m calcining kilns. The materials are then ground in proper mills. To these materials, so prepared and so ground, are added from one-third to one-half of their weight in slag of copper smelting or other furnaces, or the slag of over-burnt cement, which, combmmg with the lime and silica, forms a cement which is much nearer the colour of stone than any of the Koman cements heretofore made. Now, as the combination of chalk and clay, or river mud, is expensive when manufactured, and causes these cements to be very dear ; and further, as the materials are only combined mechanically and not chemically, there is neither uniformity in their quality, nor can reliance be always placed on their stability ; the object of my invention, therefore, is to lessen the expense of manufacturing artitcial stone mortars, and cements, and produce a superior quality of cement to those now in use. My invention divides itself into three parts; the first of which relates to mortar and cements, the second to the manufacture of artificial stone, and the third to the modes of manufacturing the said mortar cements, and artificial stone. "I have found by research, analysis, and much experience, that there exists in nature vast beds of argillaceous maris and mariy limestones, or mari stones, which contain tha due admixture of lime, silica, and alumina, from which hydraulic cements and artificial stone may be manufactured. The principal places for findmg this mari and marly CEMENTS. 398 limestone (geologically speaking) are the chalk formation, the Wealden formation the Purbeck beds, the lias formation, the mountain limestone, and the lowest strata ot the coal measures. In the chalk formation, the mari will be found immediately at the junction of chalk with and just above the green sand; in that division of the sand usually called ' gault,' or at such places where the fire-stone (or, as it is sometimes called; the 'malen rock') exists, interposing between the gault and the cha k marl This chalk mari possesses a varying character, increasing in the amount ot silica ana alumina as it approaches either the malen rock or the gault ; in fact, sometimes when there is no malen rock (or fire-stone) the gault becomes a calcareous mari, charged witn sufficient lime to make a cement, but the amount of silica and alumina, and lime com- posing the marL can only be ascertained by experiment The upper beds of marl, and those nearest to the greystone rock of the chalk formation, will make hydraulic mortar quite equal, and often superior, to the best lias lime; and the lower beds will make cement equal to Roman cement, except that it does not contain a very noticeable quantity of either manganese or iron ; consequently it is of hght stone colour when manufactured, and is better adapted to cover buildings, and represent stone. The chalk mari may readily be found by the springs of water which issue from the back or escarpment face of the chalk formation, and above these springs (but m close proximity thereto) the hydraulic lime will be found, and below the springs the materials for making cement must be extracted. , , ttt i ^ ^ i.- "The proper place for obtaining the marly limestone in the Wealden fomation ism what are termed by geologists the Ashburuham beds, above and below and m imme- diate contact with the Ashburnham limestone. These limestone maris are like perfect limestone when first extracted, but decompose by exposure to the air after a short time. The limestone itself, in particular localities, sometimes become a cement-stone or marl stone, which may be known by its not slackening in water after calcination. "The material for making cement out of the beds of Purbeck limestone is obtained from some of the partings which divide the ordinary Purbeck beds of limestone, and is exceedingly well calculated to make a cement of great purity and whiteness, but all the beds do not contain in their partings the quality desired, but the proper material may be readily found by noticing the decomposing character of the shale when ex- ^^The'^materials which I extract from the lias formation, locally called 'i-ummell' at the lime quarries at Barrow-on-Soar, in Leicestershire, is an especial bed o[ marty limestone, found above and separated from all the lias beds of limestone in that di^ trict The same bed of ' rummell ' is found in other districts of the has formation, and may be readily observed on the coast of Dorsetshire, near Lyme Regis. It is seen on the face of the liniestone cliffs, imbedded in a mariy shale, the whole of which decomposes on exposure to the air. This bed of ' rummell ' has no local name in the district of Lyme Regis, not having hitherto been applied to any useful purpose ; but it may be easily found, as it exists in a deep bed of shale between the lias limestone beds and the beds of cement stone which heretofore have been worked, and are so now (but the cement from this last-named stone is of a deeper brown colour, and unfit for imitating stone, whilst the bed of ' rummell ' will make a cement of a light colour exactly like freestone). " In some cases, as when I use the hardening materials (to be hereafter described) in combination with the calcareous marls from the lias formation I use sonie of the partings of calcareous shale existing between the lias beds of workable limestone, pro- vided Such calcareous partings or shale beds contain sufficient lime, which shale, after calcination, I combine with the hardening material, in the manner hereafter to be directed, either by itself or in combination with the ' rummell of this formation along with the hardening materials. „ , , . . -e " The materials which I extract to make cements from the mountain or carboniterous limestone are only found in the upper part of that great deposit, and must be sought for in or at the immediate junction of the limestone shale (which shale lies under the mill-stone grit, and above the mountain or carboniferous limestone, dividing the two formations) These materials consist of mountain limestone, limestone shale, and bas- tard limestone (that is, the limestone which will not slack after calcination, but still retains its shape after being dipped in water). These two materials are found above the beds of workable limestone, which beds are wrought for making ordinary limes (the shales and the bastard limestone, or limestone mari, being always tound together). These shales produce a dark cement, but the bastard limestone produces a cement of a light stone colour, and therefore more fit for imitating stone. " In addition to these substances, I extract from this formation sparry iron stone, to make hardening materials with. a. r "The materials which I extract from the coal measures for making cement, or for mixing with the other cementitious materials, are found only in the lowest beds of the coal measures, often connected with the last two seams of coal, and before that Vol. L 3 E ! 394 CEMENTS. I stratum the millstone grit. These cementitious materials consist, first, of the coal 8hal« (called metals by miners), and round septaria nodules (boilams by the local miners about Congleton in Cheshire). The 'metals' will not in all cases make cement, but most of them in contact with the boilams (or septaria balh) will do so. These boilams are composed chemically of sulphur, lime, iron, and manganese, and are therefore easily distinguishable ; they are, in fact, a species (as well as the ' metals ') of pyrites. The ' metals ' and the septaria balls make excellent cement, of great hardness, but of dark colour. I use, however, this cement, as well as other materials, in mixing with Bome of the cements 1 have before specified, to give them hardness — the process of doing wlvich, and the nature of the materials, will be described hereafter — such ma- terials wiil be called hardening materials. " When any of the materials just enumerated are to be made into cements, the usual course of proceeding for making cements is to be followed ; that is, by burning in kilns and grinding in mills, in the way cement is now manufactured ; but I recommend that the marls and marl stones be first dried in kilns or ovens, at a heat fit for baking until all moisture be driven off^ and that then the calcination be prolonged as much as possible, but that the heat be kept so low as is only just sufficient to effect complete calcination, — this being indispensable, to avoid the commencement of vitrification, which would destroy the adhesive properties of the cement. These observations will be found equally applicable to kilns, such as are now in use, or to the kiln of the im- proved description, to be described hereafter, and which forms part of this invention. " Although I have described certain new materials for making cements and mortars therefrom, and such materials are capable of forming good cements without any ad- mixture whatever, yet, in some cases, I make a composition of the various cements to obtain particular qualities ; thus, for instance, I take a quantity of the pyrites septaria, called boilams, and mix it with an equal quantity of the chalk marl before described. In this case the chalk marl keeps the colour light, and the septaria or boilams of the coal measures before described give to the chalk marl a considerable degree of hardness. I also make a mixture of equal parts of the bastard limestone before de- scribed for a like purpose, and with the same result ; but with the ' rummells ' of the lias formation before described, or the rich argillaceous shale of that formation, no\ more than one-third or one-quarter part by weight of the septaria or boilams is need ful to give great hardness and strength to the cement made therefrom. The same ob servation applies to the cement stone of the Ashburnham beds already described, a» well as the cement made from the interposing Purbeck shale partings. " But in many cases a cement is required of a hardness beyond what would bf aflForded from either of the cement stones I have described, or the mixture of two oi more of them together ; and in these cases I use substances to be combined with any of these cement stones or their mixtures, which I have called 'hardening materials. These materials (in addition to the one I have described, namely, the pyritous septaria or boilams) consist — " First : Of the slag or cinder derivable from iron blast furnaces. " Secondly : Slag from puddle furnaces, or from reheating or mill furnaces. "Thirdly : Slag derivable from copper, lead, or tin furnaces, or the slag from cement kilns. ** Fourthly : The sparry iron of the carboniferous strata. " Fifthly : The pyritous earth known by geologists as Folkestone pyrites, which pyritous earth is a thin lamina, or bead, or band of earth, in concretions just below the gault strata, and which it separates from the rock and sand bed just below the gault. The pyrites may be found in other places in similar positions ; but the locality just in- dicated, namely, Folkestone in Kent, will be a sufficient guide to find a similar material elsewhere. This pyritous earth may be calcined in ordinary lime kilns, the same as the cement stones I have before enumerated. If this pyrites be mixed with chalk marl or any other of the white cement stones I have before mentioned, the imitation of stone will be very exact, and may be sculptured afterwards with the same facility as ordinary freestone. The same effect may be produced by mixing in the like propor tions this calcined pyritous earth with the artificial hydraulic cements now commonly made (and which cements are composed of chalk and clay, or mud, in due proportions, and ground together before calcination), the pyritous earth or Folkestone pyrites dis- placing in thid case the ground slag with which such cements are now usually combined. " The various slags and cinders require only to be ground under edgestones to a fine powder, and then to be mixed with any of the various cements I have enumerated, namely, the cement from the chalk, the cement from the lias, the cement from the Wealden and Furbeck beds, the cement from the mountain limestone, and the cement from the coal measures ; these mixtures must be effected by sifting the materials together, or by some other mode which will effectually incorporate and combine them ; and the CHAINWORK. 395 quantities may be generally from one quarter (by weight) to one of slag, mixed -with ''''« ?nsomrcase?r grind pyritous septaria of the coal measures, or other equivalent materials (having the same chemical properties), into a fine powder, and mix such powder with aboSt its equal weight of some of the calcareous mar s after they are made Fnto cement, instead of mixing such marls with the slags, or with the calcined Pyntes of Folkestone, as before directed. In other cases, I mix with the cement made trom chalk or other marls an equal weight of any of the cements now in use, or ol the calcined septaria of the London clay basin, called Roman cement stone more especially that part of it which is called sandstone ; but in the case of using any of the septaria ol the London clay, the marl and the stone may be calcined, and ground together in equal proportions, or thereabouts. . , "Claims —1st The manufacture of mortar and cement from chalk marls, tlie cal- careous marls of the Ashburnham beds, the calcareous shales of the Purbeck formation, the rummell beds of the lias formation, the calcareous and mountain hmestome shales, bastard limestone and the * metals,' and pyritous septaria of the coal formation, all or any of them, when prepared for the purpose by grinding or pounding, and by treating with water as described, and whether the same are combined or not combined with certain hardening materials (afterwards specified), or other cementitious substances. " 2 The use of the ' hardening materials' described, when used in combination with any of the calcareous substances enumerated in the preceding claim, or in combmation with any other natural calcareous marl or marlstones. " 3 The use of the calcined Folkestone pyritous earth, the sparry ironstone or white ironstone of the mountain limestone, and the calcined pyritous septaria of the coal measures, as ' hardening materials' in combination with any artiticially-formed cement composed of chalk, or lime and clay, ground and calcined m the manner now usually practised for manufacturing artificial cements. "4 The mixture of any of the before described marls or marlstones, or pyritous septaria, from the coal measures, with each other, or with any of the water cemenU or limes now in use, or the materials of which the same are composed. " 5. A particular process of grinding and pounding cement and materials mixed therewitli, as described. .,.,.., i *. i " 6. The consolidation of cement and materials mixed with such cement by concus- sion, for forming blocks or other solid shapes in moulds. « 7 A process of making artificial stone by putting plastic materials between lattices or other convenient forms ; and also certain methods of casting hollow parallelograms in cement, to be afterwards filled up with concrete, for walls of artificial stone. " 8 The use of a kiln, with fire-vaults under the whole area of such kiln, such vaults communicating with each other in various directions through spaces between the bncks composing such vaults. . ,. ,^ j -i, j r " 9 The use of a brick with projections for constructing fire-vaults, as described, tor calcining marls, marlstones, cements, and other materials used for making metallic " 10. The use of a circular or continuous kiln, for the purpose of making mortars CERASIN. The name given by Dr. John to those gums which swell, but do not dissolve in water; such as gum tragacanth. It is synonymous with Bassorink, CERATE, from cerOy wax. An unguent, of rather a stiff consistence, made of oil, or Urd and wax, thickened occasionally with pulverulent matters. CERINR A substance which forms from 70 to 80 per cent, of bees -wax. It may be obtained by digesting wax, for some time, in spirits of wine, at a boiling temperature. The viyricine separates, while the cerine remains dissolved, and may be obtained from the decanted liquor by evaporation. Cerine is white, analogous to wax, fusible at 184° F hardly acted upon by hot nitric acid, but is readily carbonized by hot sul- phuric 'acid. When treated with caustic alkaline lye, it is converted into margaric acid and ceraine. , . , • •, ^^ 3 -^ r a CERIUAL A peculiar metal discovered in the rare mineral, called cente, louna only in the copper mines of Bastnaes, near Riddarhytta, in Sweden. Ceriuni extracted from its chloride by potassium, appears as a dark red or chocolate powder, which assumes a metallic lustre by friction. It does not conduct electricity well, like other metals ; it is infusible ; its specific gravity is unknown. It has been applied to no use CERUSK A name of white lead. See Lead and Wbtie Lead. CETINK The name given by Chevreul to spermaceti CHAINWORK is a peculiar style of textile fabric, to which hosiery and tambour- ing belong. Sec Hosieey. 8£2 f 896 CHAMELEON MINERAL. CHALK. {Craie, Fr. ; Kreide, Germ.) A friable carbonate of lime, white, opaqne, Boft, dull, or without any appearance of polish in its fracture. Its specific gravity varies from 2-4 to 26. It usually contains a little silica, alumina, and oxide of iron. It may be purified by trituration and elutriation. The siliceous and ferruginous matters subside first, and the finer chalky particles floating in the supernatant liquid may be decanted with it, and obtained by subsidence. When thus purified, it is called whitening and Spanish white, in England ; schlemmkreide, in Germany ; blanc cfe Troyes, and Uanc de Meudon, in France. Pure chalk should dissolve readily in dilute muritaic acid, and the solution should afford no precipitate with water of ammonia. CRKLYi-hlack. A mineral, called also drawing-slate. CRXLK- French. Steatite, or soap-stone ; a soft magnesian mineral. CHALK-re F., are saturated with pure peroxide of iron, in the washed state, after being precipitated by ammonia from the ferric sulphate. The solution is sweetened, fla- voured, and charged highly with carbonic acid gas, so as to make a very palatable potion, agreeable also to the stomach. I find by analysis that 100 parts of Mr. Bewley's brilliant citrate of iron contain 28-9 of peroxide, 48 5 of citric acid, and 23 of water ; and that a six-ounce phial of his chalybeate water contains of that citrate a quantity equivalent to nearly 8 grains of peroxide of iron. Similar compounds are also specified to be made with other organic salts, as the tartrate or lactate of iron. — Newton's Journal^ xxii. 470. CHAMELEON MINERAL. As this compound— so long known in chemistry as a mere curiosity, on account of the surprising changes of color which it spon- taneously assumes— has of late been largely employed for whitenir? tallow, palm oil, and decoloring other organic matters, it merits description in this dictionary. It exists in two states ; one of which is called by chemists the manganate of potash, and the other the oxymanganate; denoting that the first is a compound of manganic acid with potash, and that the second is a compound of oxymanganic acid with the same base. They are both prepared in nearly the same way; the former by calcmmg together, at a red heat in a covered crucible, a mixture of one part of the black per- oxide of manganese with three parts of the hydrate of potash (the fused potash of the apothecary). The mass is of a green color when cold. It is to be dissolved in cold water, and the solution allowed to settle, and become clear, but by no means filtered for fear of the decomposition to which it is very prone. When the decanted liquid is evaporated under the exhausted receiver of an air-pump, over a surface of sulphuric acid, it afi'ords crystals of a beautiful green color, which should be laid on a clean porous brick to drain and dry. They may be preserved in dry air, but should be kept in a well-corked bottle. They are decomposed by water, but dissolve in weak water of potash. On diluting this much, decomposition of the salt ensues, with all the chameleon changes of tint ; red, blue, and violet. Sometimes a green solution of this salt becomes red on being heated, and preserves this color even when cold, but resumes its green hue the moment it is shaken : it might, therefore, furnish the crafty votaries of St. Januarius with an admirable means of mystifying the worshippers at his shrine. The original calcined mass, in being dissolved, always deposites a considerable quantity of a brown powder, which is a compound of the acid and peroxide of man- ganese combined with water. Much of the potash remains unchanged, which may be recovered. The oxymanganate of potash is made by fusing, with a strong heat, a mixture of equal parts of peroxide of manganese and hydrate of potash, or one part of peroxide and two parts of nitre. The mass is to be dissolved in water, and, if the solution be green, it should be reddened by the cautious addition of a few drops of nitric acid. The clarified liquor is to be evaporated to the point of crystallization. Even the smallest crystals of this salt have such an intense red color, that they appear black with a green metallic reflection. In the air they gradually assume a steel gray hue, without undergoing any essential change of nature. A very little of the salt reddens a lar^'e body of water. The least portion of any organic matter added to the solution of this salt reduces the oxymanganic acid to the state of peroxide, which precipitates combined with water ; and the liquor becomes green or colorless, according to circum- A more permanent oxymanganic salt may be made as follows : — Melt chlorate of potash over a spirit lamp, and throw into it a few pieces of hydrate of potash, which CHARCOAL. 397 immediately dissolve and form a Hmpid liquid. Whe^^^^^^^^ powder is ^adually introduced mto ^"^^^ '^^^^^'^'f^l^'^^^^ when boiled assumes a fine red colour, in consequence ol its ^^?f ™'"^Hnir and still LnAtP and it ought to be decanted off the sediment while hot. By cooling, and stm ment rfoxygen! a^nd tlfe destruction of many vegetable and animal eolour^ In tto w«nPot thev resemble the nitrates and chlorates. . ^ j» rHARCOAL The fixed residuum of vegetables exposed to ignition out of contact of air ^the article Carbon; I have described the general properties of charcoal and th^ S^plesl mXof mak'ng it. I shaU here detail the best systems of manufacturmg thi. ^'tcarTnize'^o^t?^^^ very much in Germany. The wood is arranged either in horizontal layers, or innear^ I!rtJr«l ones with a sli-ht slope, so as to form conical rounded heaps of difl^errnt sizes. The foim^irrclire^^^^^^^^ 339 ; the latter standing metier, fi,s. 340 and 341. 844 341 Both are distributed in much the same way. In districts where the wood can be transported into one place by means of rivers, or mounSSera Vflat space must be pitched upon, screened from storms and flood^ Xch r^ay be walS round, having a slight declivity made in the ground, toward the Tentre. See 5ig. 342. Into' this s^ace the tarry acid will partially fall, and may be inducted outward, through a covered gutter beneath, into a covered tank The mouth of the tank must be shut, during the coaking, with an iron or stone slab, luted wUh clay. A square iron plate is placed over the inner orifice of the gutter, to prevent Wiinciay. a S4"« i r .it being choked with coal ashes. Fig. 342 represents a walled meiler station : a, the station ; 6, the gutter ; c, the tank, which is cov- ered with the slab d ; e, a slab which serves to keep the gutter dear of coals. The cover of the heaps is formed of earth, sand, ashes, or such other matter as may be most readily found in the woods. They should be kindled m the cen- tre From 6 days to 4 weeks may be required for charring a heap, according to its size ; hard wood requiring most time ; and the slower the process, the belter and greater is the product, generally speaking. ^^^ ^^^^.^^ ^^ ^^^^ .^ ^^^^^^ (Hau/e or lie^ende uerke), figs. 343 and 344, difiers from that in the meiler, because the wood in the haufe is successively charred, and the charcoal is raked out by little and little. The product is said to be greater in this way, and also better. Uncleft billets, 6 or 8 feet long, being laid over each other, are covered with ashes, and then carbonized. The station is sometimes horizontal, and some- times made to slope. The length may be 24 feet, the breadth 8 feet : and the wood is laid crosa- 398 CHASCHISCH. wise. Piles are set perpendicularly to support the roof, made of boughs and leaves, covered with ashes. Pipes are occasionally laid within the upper part of the mounds, which serve to catch and carry off some of the liquid products into proper tanks. Fig. 345 is a vertical section, 345 „ . fifO and /g. 346, a half bird's-eye view, and half cross section, at the height of the pit-bottom, of Chabeaus- siere*s kiln for making wood char- coal, o is the oven; b, vertical air-pipes ; c c, horizontal flues for admitting air to the kiln ; d d, small pits which communicate by short horizontal pipes e e, with the vertical ones ; /, the sole of the kiln, a circle of brickwork, upon which the cover or iU»od h reposes; t, a pipe which leads tc the cistern k ; /, the pipe destined for carrying off the gaseous matter ; m m, holes in the iron cover or lid. The distribution of the wood is like that in the horizontal meikrsy or heaps ; it is kindled in the cen- tral vertical canal with burning fuel, and the lid is covered with a few inches of earth. At the be- ginning of the operation all the draught flues are left open, but they are progressively closed, as occasion requires. In eight kilns of this kind, 500 decasters of oak wood are carbonized, from which 16,000 hectolitres of charcoal are obtained, equal to 64,000 pounds French, being about 25 per cent. ; besides tar and 3000 veils of wood vinegar, of from 2° to 3* Baume. At Crouy upon the Ourcq, near Meaux, there is a well-constructed kiln for making lurf-charcoal. It resembles most nearly a tar-kiln. In^g. 347, a is the cylindrical coaking place, whose surrounding walls are heated by the flame which passes through the intermediate space b. The place itself is divided by partitions of fife tiles into three stages, through the apertures in which the flames of the fire c c, rise, and heat the exterior of the coaking apartment. In order to confine the heat, there is in the enclosing walls of the outer kiln a cylindrical hollow space d, where the air is kept stagnant. Through the apertures left in the upper end at €, the turf is in- troduced ; they are then shut with an iron plate /, which is covered with ashes or sand. The fire-place opens above this aperture, and its outlet is pro\'ided with a moveable iron cover g, in which there is a small hole for the issue of the gases. The sole of the kiln consists of a cast iron slab A, which may be raised by means of a hook t upon it. This is drawn back after the carbonization is completed, whereby the charcoal fulls from the coaking space into a subjacent vault. The volatile products are carried off by the pipe k, and led into the condensing cistern ; the gases escaping to the fire-place where they are burned. The iron slab is protected from the corrosion of the acid vapors by a layer of coal ashes. CHASCHISCH. Hadschy is not the correct term for this narcotic drug, for Iladschy means a pilgrim ; the true name is, according to pronunciation, Chaschisch, the Arab word for hemp (Cannabis saliva). By this name all intoxicating drugs, whose chief constituent is this herb, are well known over the whole of the East The mode of preparing chaschisch is the following: — CHIMNEY. 399 The tops and all the tender parta of the hemp plant are collected aft^er the period of inflorescence, dried and kept for use. It must be premised that the hemp plant is in the East distinguished by its narcotic properties, although botanists are unable to detect any diflference between this and the European species. The dried hemp, or chaschisch, Ist foiled in fat, butter, or oil, with a little water ; the filtered product is employed in all kinds of pastry. , ^ r 2nd. Powdered for smoking : 5 or 10 grs. of the powder are smoked from a common pipe (tmbuk) with ordinary tobacco {tutwn), or from a water pipe {nargide) with another kind of tobacco {tombeki). Tlie torabeki is probably the leaf of a species of Lobelia; it is smoked in a nargiele, and is uncommonly nareoctic ; so much so, tliat it is ordinarily steeped in water for a few hours before it is used to weaken it, and the pipe is charged with it whilst it is yet wet 3rd. Formed with tragacanth mucilage into pastiles, which are placed upon a pipe and smoked in similar doses. These two last preparations are so termed esrar {esrar is the Arab word for " secret") ; they are the most active of all the preparations of chaschisch, and the first pipe will cause cerebral congestion in beginners. 4th Made into an electuary with dates or figs and honey. This preparation is of a dark brown, almost black, colour, and tastes of dates and hemp ; it is less active than tjnf^ fisrftr 5th. Lastly, another electuary is prepared of the same ingredients with the addition of spices, clove, cinnamon, pepper, amber, and musk. This preparation is used as an aphrodisaic. , . *•*•*• Chaschisch is said not to produce stupor but the most pleasant species of intoxication. The person under its influence feels with perfect consciousness m the best of all humours; all impressions from without produce the most grateful sensations; pleasant illusions pass before his eyes, and he feels comfortably happy; he thinks himselt the happiest man on earth, and the world appears to him Paradise. From this imaginative state he parses into the every day state, with a perfect recollection of all sensations, and of every thing he has done and of every word he has spoken. The effects ot a con- tinued use of Ihe narcotic are emaciation and nervous debility. CIIEPiSE {composiMon of). Cheese of certain dairies and districts is apt to undergo a remarkable decomposition whereby valerianic acid is formed. Messrs. Jljenko and Laskowsi distilled along with water a turbid ammoniacal liquor, which being redistilled along with some sulphuric acid, and the product neutralized by barytes, the resulting saline compound proved to be the valerianate of that base, mixed with compounds ot butyric acid, caproic acid, eaprylic acid, and capric acid. The cheese was from Limbourg. Valerianic acid was found by M. Balard in the cheese of Roquefort CHICA is a red colouring principle made use of in America by son;e Indian tribes to stain their skins. It is extracted from the bignonia chica by boiling its leaves in water, decanting the decoction, and allowing it to settle and cool, when a red matter falls down, which is formed into cakes and dried. This substance is not fusible, and, when burned, diffuses the same odor as animal bodies do. t is insoluble in cold water, very soluble in alcohol and ether, but after the evaporation of these liquids, it is recovered unchansed. Fats and unctuous oils both dissolve it. It is soluble in carbonated and caus- tic alkaline leys, from which it is precipitated by the acids without alteration. An excess of alkali, however, speedily decomposes it. Nitric acid transforms it into oxalic acid, and a bitter matter. Chlorine makes it white. , k • The savages mix this pigment with the fat of the cayman or alligator, and rub their skins with the mixture. It may probably be turned to account in the arts of civilized nations. . , . ,. CHIMNEY. (C/icmtWe, Fr.; Sc/lonw/ciTJ, Germ.) Chimney is a modern invention for promoting the draught of fires and carrying off the smoke, introduced into England so late as the age of Elizabfath, though it seems to have been employed in Italy 100 years before. The Romans, with all their luxurious refinements, must have had their Epicurean cookery placed in perpetual jeopardy from their kitchen fires, which, having no vent by a vertical tunnel in the walls, discharged their smoke and frequently their flames at the windows, to the no small alarm of their neighbors, and annoyance of even the street passengers. i u • . Chimneys in dwelling houses serve also the valuable purpose of promoting salubrious circulation of air in the' apartments, when not foolishly sealed with anti-ventilating stove- chests. J , The first person who sought to investigate the general principles of chimney drausnis, in subserviency to manufacturing establishments, was the celebrated Montgolfier. As the ascent of heated air in a conduit depends upon the diminution of its specific gravity, or, in other words, upon the increase of its volume by the heat, the ascensional force may we deduced from the difference between the density of the elastic fluid in the mterior of 400 CHIMNEY. *he chimney, and of the external air ; that is, between the different heights of the interna] and external columns of elastic fluid supposed to be reduced to the same density. In the latter case, the velocity of the gaseous products of combustion in the interior of the chim- ney is equal to that of a heavy body let fail from a height equal to the difference in height of the two aerial columns. To illustrate this position by an example, let us consider the simple case of a chimney of ventilation for carrying off foul air from a factory of any kind ; and suppose that the tunnel of iron be incased throughout with steam at 212 degrees Fahr. Suppose this tunnel to be 100 yards high, then the weight of the column of air in it will be to that of a column of external air 100 yards high, assumed at 32? F., inversely as its expansion by 180® ; that is, as 1000 is to 1-375; or as 72*727 is to 100. The column of external air at 32° being 100 yards, the internal column will be represented by 72*727 ; and the dif- ference=27*27, will be the amount of unbalanced weight or pressure, which is the effec- tive cause of the ventilation. Calculating the velocity of current due to this difference of weight by the well-known formula for the fall of heavy bodies, that is to say, multiplying the above difference, which is 27*27, by the constant factor 19.62, and extracting the square root of the product ; thus V 19*62 X 27*27 = 23*13 will be the velocity in yards per second, which, multiplied by 3, gives 60*30 feet. The quantity of air which passes in a second is obtained of course by multiplying the area or cross section of the tunnel by this velocity. If that section is half a yard, that is = a quadrangle 2| feet by 2, we shall have 23*13 X 0*5 = 11*565 cubic yards, = 312^ cubic feet. The problem becomes a little more complicated in calculating the velocity of air which has served for combustion, because it has changed its nature, a variable proportion of its oxygen gas of specific gravity 1*111, being converted into carbonic acid gas of specific gravity 1*524. The quantity of air passed through well constructed furnaces may, in general, be regarded as double of what is rigorously necessary for combustion, and the proportion of carbonic acid generated, therefore, not one half of what it would be were all the oxygen so combined. The increase of weight in such burned air of the temperature of 212?, over that of pure air equally heated, being taken into account in the preceding calculation, will give us about 19 yards or 57 feet per second for the velocity in a chim> ney 100 yards high incased in steam. Such are the deductions of theory ; but they differ considerably from practical results, in consequence of the friction of the air upon the sides of the chimneys, which varies like- wise with its form, length, and quality. The direction and force of the winds also exercise a variable influence upon chimney furnaces differently situated. In chimneys made of wrought i'X)n, like those of steamboats, the refrigeration is considerable, and causes a diminution of velocity far greater than what occurs in a factory stalk of well built brick work. In comparing the numbers resulting from the trials made on chimneys of dif- ferent materials and of different forms, it has been concluded that the obstruction to the draught of the air, or the deduction to be made from the theoretical velocity of efflux, is directly proportional to the length of the chimneys and to the square of the velocity, and inversely to their diameter. With an ordinary wrought-iron pipe, of from 4 inches to D inches diametei, attached to an ordinary stove, burning good charcoal, the difference b prodigious between the velocity calculated by the above theoretical rule, and that ob- served by means of a stop-watch, and the ascent of a puff of smoke from a little tow, dipped in oil of turpentine thrust quickly into the fire. The chimney being 45 feet high, the temperature of the atmosphere 68° Fahr., the velocity per second was, — Mean temperature Trials. By theory. By experiment, of chimney. 1 26.4 feet 5 feet 190° Fahr. 2 29*4 5-76 214 3 34*5 6*3 270 To obtain congruity between calculation and experiment, several circumstances must be introduced into odr formula. In the first place, the theoretical velocity must be multiplied by a factor, which is different according as the chimney is made of bricks, pottery, sheet iron, or cast iron. This factor must be multiplied by the square root of the diameter of the chimney (supposed to be round), divided by its length, increased by four times its diameter. Thus, for pottery, its expression is 2*06 V D L-j-D ; D being the di- ameter, and L the length of the chimney. A pottery chimney, 33 feel high, and 7 inches in diameter, when the excess of its mean temperature above that of the atmosphere was 205° Fahr., had a pressure of hot air equal to 11*7 feet, and a velocity of 7*2 feet per second. By calculating from the last fonnul&j ihe same number very nearly is obtained. In none of the experiments did the velocity exceed 12 feet per second, when the difference of temperature was more than 410° Fahr. CfflMNEY. 401 Every different form of chimney would require a special set of experiments to be made for determining the proper factor to be used. This troublesome operation may be saved by the judicious application of a delicate differential barometer, such as that invented by Dr. Wollaston ; though this instrument does not seem to have been applied by its very ingenious author in measuring the draughts or ventilating powers of furnaces. If into one leg of this differential syphon water be put, and fine spermaceti oil into the other, we shall have two liquids, which are to each other in density as the numbers 8 and 7. If proof spirit be employed instead of water, we shall then have the relation of very nearly 20 to 19. I have made experiments on furnace draughts with the instrument in each of these slates, and find the water and oil syphon to be sufficiently sensible ; for the weaker draughts of common fire-places the spirits and oil will be preferable barometric fluids. To the lateral projecting tube of the instrument, as described by Dr. Wollaston, I found it necessary to attach a stop-cock, in order to cut off the action of the chimney, while placing the syphon, to allow of its being fixed in a proper state of adjustment, with its junction line of the oil and water at the zero of the scale. Since a slight de- viation of the legs of the syphon from the perpendicular changes very considerably the line of the level, this adjustment should be made secure by fixing the horizontal pipe tightly into a round hole, bored into the chimney stalk, or drilled through the furnace door. On gently turning the stop-cock, the difference of atmospherical pressure cor- responding to the chimney draught, will be immediately indicated by the ascent of the junction line of the liquids in the syphon. This modification of apparatus permits the experiment to be readily rectified by again shutting off the draught, when the air will slowly re-enter the syphon ; because the projecting tube of the barometer is thrust into the stop-cock, but not hermetically* joined ; whereby its junction line is allowed to retom to the zero of the scale in the course of a few seconds. Out of many experiments made with this instrument, I shall content myself with describing a few, very carefully performed at the breweries of Messrs. Trueman, Han- bury, and Buxton, and of Sir H. Meux, Bart., and at the machine factory of Messrs. Braithwaite ; in the latter of which I was assisted by Captain Ericsson. In the first trials at the breweries, the end of the stop-cock attached to the differential barometer was lapped round with hemp, and made fast into the circular peep-hole of the furnace door of a wort copper, communicating with two upright parallel chimneys, each 18 inches square and 50 feet high. The fire was burning with fully its average intensity at the time. The adjustment of the level being perfect, the stop-cock orifice was opened, and the junction level of the oil and water rose steadily, and stood at 1^ inches, corresponding to ii2 5. — 0-156 of 1 inch of water, or a column of air 10*7 feet high. This difference of pressure indicates a velocity of 26 feet per second. In a second set of experiments, the extremity of the stop-cock was inserted into a hole, bored through the chimney stalk of the boiler of a Boulton and Walt steam-engine of twenty-horse power. The area of this chimney was exactly 18 inches square at the level of the bored hole, and its summit rose 50 feet above it. The fire-grate was about 10 feet below that level. On opening the stop-cock, the junction line rose 2^ inches. This experiment was verified by repetition upon difl'erent days, with fires burning at their average intensity, and con- suming fully 12 lbs. of the best coals hourly for each horse's power, or nearly one ton and a third in twelve hours. If we divide the number 2| by 8, the quotient 0*28 will represent the fractional part of 1 inch of water, supported in the syphon by the un- balanced pressure of the atmosphere in the said chimney; which corresponds to 19J feet of air, and indicates a velocity in the chimney current of 35 feet per second. The consumption of fuel was much more considerable in the immense grate under the wort copper, than it was under thoi steam-engine boiler. In my experiments at Messrs. Braithwaite's factory, the maximum displacement of the junction line was 1 inch, when the differential oil and water barometer was placed in direct communication with a chimney 15 inches square, belonging to a steam boiler, and when the fire was made to burn so fiercely, that on opening the safety-valve of the boiler, the excess of steam beyond the consumption of the engine rushed out with such violence as to fill the whole premises. The pressure of one eighth of an inch of water denotes a velocity of draught of 23*4 feet per second. In building chimneys, we should be careful to make their area rather too large than too small ; because we can readily reduce it to any desired size, by means of a sliding register plate near its bottom, or a damper plate applied to its top, adjustable by wires or chains, passing over pulleys. Wide chimneys are not so liable as narrow ones to have their draught affected by strong winds. In a factory, many furnace flues are often conducted into one vertical chimney stalk, with great economy in the first erection, and increased power of draught in the several fires. Vast improvements have been made in this country, of late years, in building stalks Vol. I. 3 F 409 CfflMNEY. for steam boilers and chemical furnaces. Instead of constructing an expansive, bay scaffolding of timber round the chimney, for the bricklayers to stand upon, and to place their materials, pigeon-holes, or recesses, are left at regular intervals, a lew leet apart, within the chimney, for receiving the ends of stout wooden bars, which are laid across, so as to form a species of temporary ladder in the interior of the tunnel. Py means of these bars, with the aid of ropes and pulleys, everything may be pro- eressively hoisted, for the building of ihe highest engine or other stalks. An expert bricklayer, wiih a handy laborer, can in this way raise, in a few weeks, a considerable chimney 40 feet high, 5 feet 8 inches square outside, 2 feet 8 inches inside at the base, 28 inches outside, and 20 inches inside at the top. To faciUtate the erection, and at the same time increase the solidity of an insulated stalk of this kmd, it is buut with three or more successive plinths, or recedures, as shown in fig. 281. It is neces- sary to make such chimneys thick and substantial near the base, in order that they may sustain the first violence of the fire, and prevent the sudden dissipation of the heat. When many flues are conducted into one chimney stalk, the area of the latter should be nearly equal to the sum of the areas of the former, or at least of as many of them as shall be going simultaneously. When the products of combustion from any furnace must be conducted downwards, in order to enter near the bottom of the main stalk, they will not flow off until the lowest part of the channel be heated by burning 9ome wood shavings or straw in it, whereby the air syphon is set agoing. Immedi- ately after kindling this transient fire at that spot, the orifice must be shut by which it was introduced ; otherwise the draught of the furnace would be seriously impeded. But this precaution is seldom necessary in great factories, where a certain degree of heat is always maintained in the flues, or, at least, should be preserved, by shutting the damper plate of each separate flue, whenever its own furnace ceases to act. Such chim- neys are finished at top with a coping of stone-slabs, to secure their brickwork against the infiltration of rains, and they should be furnished with metallic conducting rods, to protect them from explosions of lightning. _ When small domestic stoves are used, with very slow combustion, as has been recently proposed, upon the score of a misjudged economy, there is great danger of the inmates bein? suffocated or asphyxied, by the regurgitation of the noxious burned air. The smoke doctors who recommend such a vicious plan, from their ignorance ot chemical science, are not aware that the carbonic acid gas, of coke or coal, must be heated 250° F. above the atmospheric air, to acquire the same low specific gravity with it. In other words, unless so rarefied by heat, that gaseous poison will descend through the onfic« of the a^h-pit, and be replaced by the lishter air of the apartment. Drs. Priestley and Dalton have long ago shown the co-existence of these two-fold crossing currents of air, even through the substance of stone-ware tubes. True economy of heat, and salubrity, alike require vivid combustion of the fuel, with a somewhat brisk draught inside of the chimney, and a corresponding abstraction of air from the apartment. Wholesome continuous ventilation, under the ordinary circumstances of dwelling houses, cannol be secured in any other way. Were these mephitic stoves, which have been of late so ridiculously puffed in the public prints, generally introduced, the faculty would need to be immediately quadrupled to supply the demand for medical advice ; for headaches, sickness, nervous aliments, and apoplexy, would become the constant inmates of every inhabited mansion. The phenomena of the grotto of Pausilippo might then be daily realised at home, among those who ventured to recline upon solas in such car- bonated apartments ; only instead of a puppy being suffocatedpro tctnpore, human beings would be sacrificed, to save two penny worth of fuel per diein. The figures upon the following page represent one of the two chimneys, recently erected at the Camden Town station, for the steam boilers of the two engines of 60 horse-power each, belonging to the London and Bimingham Railway company. Ihew engines then drew their train of carriages up the inclined plane of Hampstead HilL The chimneys were designed by Robert Stephenson, Esq., engineer to the Company, executed by William Cubitt, Esq, of Gray's Inn road, - and do equal honour to both gentlemen, being probably among the most elegant and substantial specimens ol this style of architecture in the world. In the section, /^r. 348., A represents a bed of concrete, 6 feet thick, and 24 feet square. B, brick footings set in cement; the lower course 19 feet square. c! Bramlev-fall stone base, with a chain of wrought iron let into it D, a portion, 15 feet high, curved to a radius of 113 feet» buUt entirely of Malm paviours, (a peculiarly good kind of bricks). E, shaft built of Malm paviours in mortar. F ditto, built from the inside, without exterior scaffolding. , , ^ ^, 6, the cap ornamented, (as shown in the plan alongside,) with Portland stone, the dressings being tied together with copper cramps and an iron bond. Fiq. 349. represents the mouldings of the top, upon an enlarged scale. CHINA INK. Fig. 360, a plan of the foundation, upon an enlarged scale. Fig. 361, ditto, at the level of the entrance of the flue, as seen Fig. 362., the elevation of the chimney. Fig. 363., plan at the ground level i, in /^. 348. and 862. K^fig. 348., the lightning conducting roi .349 862 m 848 4oe CHINA INK. {Eru^e de Cldne, Fr. ; Chinesischer Tusch, Germ.) The finest kind of this useful pigment is seldom met with in our markets. According to a de- scription in a Japanese book, it is made from the condensed smoke or soot of burned camphor ; and hence, when of the best quality, it has this odour. Most of the CSiina 8 F2 4(^4 CHLORATE OF POTASH. CHLORATE OF POTASH. 405 ink is made from oil-lampblack occasionally disguised as to smell, with mus^ or ^th a Httt camphor blacS. The binding substance is gelatine commonly ma^^^^ in>m parchment or as^' skin; but isinglass answers eciually ^^11. A good imita^^^^^^^ L made by dissolving isinglass m warm water, with ^^^ ^^^^t. ?,^.f .^^^i^^j^^^^^ f sodal to destroy its gelatinizing power ; and meorporatmg with that solution, by levi latioi on a porphyry slab, as much of the finest fampblack as to produce a mass o fhe DroDer cfusktence. The minute quantity of alkali serves also to saponify the oil whicruTualTy a^^^^^^^^^^ lampblack; Ind thereby to make a pigment readily miscible ^CHINTZ is a peculiar style of fast-printed calico, in which figures of at least five diflFerent colours are impressed upon a white or light coloured ^^^^^^' . ..,,,ji„^ CHLORATE OF POTASH, commonly called oxymunate of potash, inis mieresung •aline compound has become the object of a pretty extensive ^^^'^J^l^'^'^'f ^""^^^^^Jl^l of its application to make matches for procuring instantaneous light, and a detonating nowder for fire-arms. It may be prepared both in the humid and dry way. ... - _ Having made a strong solution of purified potash, or carbonate of potash, with Irom two to three parts of water, we pass through it in a Woulfe's apparatus a current of ch o- rine gas; tni it ceases to absorb any more. Chloride of potash and chloride of potassium SoXe formed as long as there is an excess of alkali in the ^ol^^^^V' ^"V" .'iwtp' in the further reaction of the materials, the chloride passes mto the state of a chlorate, and L such! precipitates from the solution. During the first half of the operation, that S^ tilHhe A^h be about one half saturated with chlorine, as indicated by litmus paper ^s ng toC darkened and beginning to be blanched, only the chloride of Potassium or S^Lte of potash falls. The process should be interrupted at this pomt in o^d^r U> re- S^fthe salt, to wash it, to add the washings to the liquor, and t^en to transmit the gj^S freely through the solution. As the operation advances less muriate ^^^i'^^'l^^J'^^; and at length nothing but the pure chlorate is separated in crystals. When finally the SSbbles of gas pass through without being sensibly absorbed, the process is known to be Seted ; the liquid ma? then be allowed to settle, and be poured ofi" from l^^e crystids Sora?e of potash, which are purified from the muriate by disso vmg them m three SmTtheVr we^^t of boiling water, and filtering the solution wh.lr hot On its coolmg, th^ch orate will separate in pearly-looking crystalline plates, li may be rendered qu.te mire by a second c^stallization, in which stite it does not affect solution of nitrate of silver. The ab^ve potaS ley usually gets a reddish tint in the course of the process in conse- Q Jnce of ImUe 1^^^^^ acid coming over wi,h the chlorine, but ,t gradually loses ^ color as the saturation becomes complete, when the s?l»tion turns .yellow. The tubes for conveying the gas should be of large diameter, if they be plunged nto the S^eS^ur, because tfe ciystallization which takes place in it is apt to ^ wT This inconvenience may however be obviated by attaching to the end of the glass rube a tube of caoitchouc terminated in a small glass funnel, or sunply the neck of a caoutchouc b^ tie with a pan of its body, whose width will not be readily closed with a salTne crust The residuary lixivium may be used against ano her operation, or it may S evaporated down to hJf its bulk and set aside to crystallize, whereby some more chSwUl be obtained, mixed indeed with muriate and carbonate, from which however it marbrseparated by k second crystallization. In general the pure chlorate obtained doS not exceed one tenth the weight of the potash employed ; because in thus treating n^tLrw'S chloiin^^^^^^ sixths of it are converted into muriate of potash and only one Sh mrchlorate, aid a part of the latter adheres to the muriate, or is lost in the mother waters of the crystaUizations. r . i i:>,« «Vo» «r ilmP in The chlorate of potash may be more conveniently manufactured like that of lime n the d'y way. St. Romer patented at Vienna the following method for that PyPO « J^ 1821 -—Ten pounds of crystallized peroxyde of manganese are to be finely P"Jye"zed» ^ei with ten'pounds of plumbago, and thirty pounds of common salt ar.d P"t »nto the leaden retort represented in fig. 287, p. 293. From the middle of the helmet-shaped hd of this vessel, a lead tube, two feet long, and two inches wide, conducts to the receiver, which is a square earthen pan, hard glazed both within and without, of the same capacity with the retort. The end of the tube must be made fast to a frame at the height of six inches above the bottom of the receiver. Upon its inner sides, four inches apart, brackets •re to be fixed for supporting a series of laths or shelves of white wood, on which a num- Lr of little paper or pasteboard boxes are to be laid. In these boxes ten pounds of the n^rei carbonate of potash, prepared from tartar, are to be spread. The receiver must now be covered with a lid made tight by a water lute. Twenty pounds of concentrated sulphuric acid previously diluted with sixteen pounds of water, and then cooled, are to b^ poured upon the mixed materials in the retort, the lid immediately secured, with the tube adiusted in the receiver. The whole must be allowed to operate spontaneously with- ouVheat for twelve hours. At the end of this time the retort is to be surrounded with a water bath and steadUy heated during twelve hours, and then left to cool for six hours. The apparatus must now be opened, the cakes of chlorate of potash removed, and freed from muriate by solution and crystallization. . « 'xccu M. Liebig proposes the following process for obtaining chlorate of potash :— Heat chloride of lime in water till it ceases to destroy vegetable colors. In this case a mixture of chloride of calcium and chlorate of potash is obtained. This is to be (UsSlved K. «H^rn;:'/.h ^ ^^l"''^" concentrated by evaporation, chloride of potassium is to be added, and then suffered to cool. After cooling, a quantity of crj stals of chlorate of potash IS obtained which are to be redissolved and crystallized again to purify them M Liebig considers that this will be a cheap process for obtaining chloral of poUh Fr^ 12 ounces of chloride of lime, of so bad a quality that it left 65 per cent of Lolubte matter, he obtained an ounce of chlorate of potash msoiuoie The only difficulty to overcome in this process is, from the chloride of lime not beine 80 easily decomposed by heat as is generally supposed ; a solution of it may be kept bi^ ing for an hour withou losing its bleaching power. The best method Ts to fom a ihk paste with chloride of hme and water, and then to evaporate it to difness IfTbe r" qujred to prepare it by passing chlorine into cream of hme, it is advi;rg;ous to keeP ^t The chlorate of potash which separates from the solution by cn'stallization has not the form of scales which it usually possesses, but is prismatic : wheSer S occasTon^ SullTrm ' "" ""' been ascertained; but on re-crystallizing, it is oirainTin tSi The solution ought not rnerely to be left to cool, in order to procure crystals for the iXT^Z^r^^Vr, f:^l ^^""^"^^^ ^^^'^ ^"- --^'^^^ '^^'^^^^ cr7statco'nUnt The following modification of the process for making chlorate of potash i«! that of M Vee. A solution of chloride of lime, marking 18° or 20^ Baume, is o be set u Jon the fifi in a lead or cast iron pot, and when it begins to get hot, there is to be dissXd in it a quantity of chloride of potassium sufficient to raise the hydrometer 3 or 4 degrees It must be then concentrated as quickly as possible till it marks 30° or 31°, takin?care'that It does not boil over by the sudden extrication of oxygen. The concent atediquor is se ^!i'i^uT^^^r l"" ^- '^^ *.'" • ^^"'•^ ^ ^^P°^'t« «^ <=^^°r^te of potash fojrmix^ with chloride of potassmm. The mother waters being evaporated to the denshv of 3^ afford another crop of crystals, after which they may be thfown awav. ^ ' The salts obtained at the first crystallization are to be re-dissolved, and the solutioa ^7of S.'' '' " '"^ " '" '^ ^''''''' "^^" '' ""^ ^-d upon1oo?iJg pTe S Chlorate or oxymuriate of potash has a cooling, somewhat unpleasant and nitrow taste. It does not bl^ch. At 60° F. 100 parts of water dissolve si parts of it and^ Its boiling point or 220°, sixty parts. When heated to dull ignition in a iass retort h gives put 39^5 per cent, of its weight of oxygen, and becomes therebfchlord^^^ potassium. When strongly triturated in a mortar it crackles, throws out sparks and ^- comes luminous. It deflagrates upon red-hot cinders like nitre : when trituraKCwirk ^.Iphur, or phosphorus, it detonates with great violence, not without danger to the hrnS of the operator. If they be not protected by a thick glove. Similar detonat on. may W produced with cinnibar or vermilion, sulphurct of potassium, su-ar vX ie oik ll but they can be effected only by the smart blow of a heated Immer and anvb A mixture of sugar or starch with chlorato of potash is readily inflamS by a drop of si phunc acid, and this experiment is the basis of the preparation of the oxy-enated m^tchS as they have been commonly called. The folloirinrfonnula fomfa g^ p^ste fo^ ippmg the said matches, made of narrow slips of either wood or card. TMrty^parts of the chlorate m fine powder are to be mixed gentlv with a .nntnio «^^.« ^ P.'Jv pans of flowers of sulphur well levigated, e&'CNveTglV^^^^^^^ of vermilion to give the whole a rose tint. We begin by mhcing tenderly togethS Ihe sugar, the gum, and the salt previously pulverised ; we then add as much water as shall reduce the mixture to a thin paste, and lastly introduce the sulphur; after which all must be well incorporated. The points of the matches, either previously tipped with sulphur or not^ are to be dipped in that paste, so as to get coated with a little of it, and are lastly laid in a warm place till they become thoroughly dry. To kindle one of. them, it must be touched with strong sulphuric acid, which, for this purpose, is usually kept in a small well-stopped vial, and thickened with amianthus. Aspen is reckoned the best wood for matches. Of late years a detonating priming for fire-arms has been much used with the percus- sion locka The simplest formula for making it is to take ten parts of gunpowder, to lixiviate it with water, and to mix the residuum, while moist, with five parts and a quarter of chlorate of potash, reduced to an extremely fine powder. The paste may be made pretty thin, for the salt is sparingly soluble in cold water, and it mixes best when tolerably fluid. This powder when dry is dangerous to handle, being very apt to \^ 406 CHLORINE. explode. But this danger is guarded against bv letting fall a drop of the paste into each copper percussion cap, and leaving it to dry there. In the detonation of this powder, besides muriate of potash, there are generated a little sulphate of potash and chlorine gas, which rust the metal very fast For which reason fulminate of mercury is now preferred by many sportsmen as a detonating powder. See Fulminate. The following ingenious and easy way of making this valuable chlorate has been lately suggested by Professor Graham : — ^Mix equal atomic weights of carbonate of potash and hydrate of lime (70 of the former, if pure, and 37 of slaked lime in powder), diffuse them through cold water, and transmit chlorine gas through the mixture. The gas is absorbed with great avidity, and the production of a boiling heat When the ^turation is complete, carbonate of lime remains, and a mixture of muriate and chlorate of potash, which latter salts are to be separated, as usual, by the difference of their solubility in water. ^ • /- ^ a It has been remarked on the above process, that it effects no saving of potassa, and therefore is far inferior to the one long practised in several parts of Germany, especially at Giessen, and introduced into this country a good many years ago by Dr. Wagen- mann, from Berlin. The chlorine is passed into a mixture of one equivalent of chlo- ride of potassium (76), and 6 equivalents of hydrate of lime (222), previously stirred with water to the consistence of a thin paste. Thus the calcium of the lime unites with the chlorine to form chloride of calcium, while the chloride of potassium is converted into chlorate of potassa, which salt is easily separated in crystals by its sparing solubility. Chlorate of potash may also be made by saturating with chlorine a mixture of 74 parts of chloride of potassium (muriate of potash) and 168 parts of quicklime, brought to the consistence of a thin pap by the cautious addition of water. The mass being dissolved in warm water, and evaporated and cooled, yields crystals of chlorate of potash, while a mother water of chloride of calcium (muriate of lime) remains. The following process has likewise been prescribed :— Mix 10 parts of good chloride of lime with water into a pap, and evaporate to dryness* whereby it is converted into a mixture of chloride of calcium and chloride of lime devoid of bleaching power ; dissolve it in water, filter, concentrate the solution by evaporation, then add to it 1 part of chloride of potassium, and cool for crystallization. Tlie salt which may thereby be separated from the chloride of calcium will afford 0-83 of pure chlorate of potash. B^ this process of Professor Liebig five sixths of the potash are saved, but much oxygen is wasted in the evaporation to dryness of the chloride of lime, and consequently much chloric acid is lost towards the production of the salt. V6e mixes the chloride of lime pap before heating it, with the chloride of potassium, boils the mixture smartly, whereby much oxygen is undoubtedly thrown off, and then sets the liquor aside to crystallize. I,. Gmelin suggests that saturation of the liquor with chlorine before boiling might be advantageous. Gay Lussac has suggested to make this valuable salt by pre- cipitating a solution of chloride of lime with carbonate (or sulphate) of potash, satu- rating the liquor after filtration with chlorine gas, evaporating, and crystallizing. ^ Profossor Juch's process is to pass chlorine gas into a mixture of 1 pound caustic lime and 1 pound carbonate of potash, with 8 pounds of water. The resulting chloride of potash readily separates in the filtered liquid by crystallization from the very soluble chloride of calcium. By this method potash is not wasted m the useless production of chloride of potassium. CHLORATES, compounds of chloric acid with the salifiable bases. The only acid be- longing to this class of any manufacturing importance is the following : CHLORIC ACID; the acid constituent of the preceding salt; it consists of one equivalent prime of chlorine = 35-476, -|- 5 of oxygen, = 40-065 ; of which the sum 75-535 is the prime equivalent of the acid. . v • i t CHLORINE ; the most energetic of the undecompounded bodies, or chemical ele- ments as they are usually called, exists, under ordinary circumstances, as a greenish yel- low gas, but, when exposed to a pressure of 4 atmospheres, it becomes a yellow transpa- rent liquid. In the first state, its density compared to air, reckoned 1-000, is 2-47; in the second, its density compared to water, 1-000, is 1-33. No degree of cold hitherto tried, has liquefied the gas when dry. It is obtained by putting into a glass re- tort a mixture of 3 parts of common salt, with 2 parts of peroxyde of manganese, and pouring upon it 2 parts of sulphuric acid diluted with its own weight of water ; or, more conveniently, by pouring moderately strong muriatic acid upon peroxyde of manganese in a retort ; and in either case applying the gentle heat of a spirit lamp or a water bath, while the beak of the retort is plunged under brine upon the shelf of the pneumatic trough. The gas issues, and may be received in the usual way into inverted glass jars, or vials j but the first which comes over, being mixed with the air of the retort, must be rejected. It has a peculiar smell, and irritates the nostrils most violently when inhaled, as also the windpipe and lungs. It is eminently noxious to animal life, and, if breathed in its un- diluted state, would prove instantly fatal. It supports the combustion of many bodies. 1 CHLORIDE OF LIME. 407 and indeed spontaneously bums several without their being previously kindled. The resulting combinations are called chlorides, and act most important parts in many manufacturing processes. Water absorbs, at the ordinary temperature of the atmosphere, about double its vo- lume of chlorine, and acquires the colour, smeU, and taste of the gas, as well as its power of destroying or bleaching vegetable colours. When this aqueous chlorine is cooled to 36 Pahr. dark yeUow crystalline plates appear in it of the hydrate of chlorine, which are composed in 100 parts of 27-7 chlorine, and 72-3 water, ff these crystals be heated to about 46° they hquefjr, and the gas flies off. Chlorine has a powerful affinity for hydrogen, not only combining with it rapidly in the gaseous, but seizing it in many of its liquid and solid combinations, as in volatile oils, which it inflames, and m yellow wax, cotton and flax, which it whitens. The com ^^^u^^ ^^.;**^^"?« *°<1 hydrogen gases is muriatic acid gas. Manganese, when mixed with liquid muriatic acid, as m the above process, abstracts the hydrogen, and lets the chlorine gas go free. When chlorine is passed into water, it decomposes some of it, seizes Its hydrogen to form a little muriatic acid, and enables its oxygen to unite either with the chlorine, into chlorous acid, or with the remaining water, and to constitute oxygen- ated water. Hence, aqueous chlorine, exposed to the sunbeam, continually evolves oxygen, and, ere long, becomes muriatic acid. This watery compound acts in a powerful way upon coloured vegetable fibres, ex- tracting their hydrogen or colouring element by the twofold affinities of the chlorine «nd oxygen for it Hence chlorine as a bleaching a^ent, requires to be tempered by the quiescent affinity of some alkaline base, potash or lime. Malaria, or morbific and putrescent miasmata^ consists chiefly of hydrogenous matter as their basis, and are best counteracted by chlorine, where it can be conveniently applied. Chlorides of Potmk, Soda, and Lime.— These are the most important preparations through which chlorine exercises its peculiar powers upon the objects of manufactures. When a weak solution of caustic potash or soda is saturated with chlorine, it affords a bleaching liquor which is still used by some bleachers and calico-printers for their most delicate processes ; but the price of the alkalis has led to the disuse of these chlorides as a general means, and has occasioned an extensive employment of chloride of lime. Upon the manufacture of this interesting compound I made an elaborate series of experiments, ^^VVolT ft' Publishea the results in the 13th volume of Brande's Journal for April, 182i. 1 have no reason to suppose, from any thing that has been published since, that the processes there described have been essentially improved, or that any errors, either theoretical or practical, of any moment, exist in that memoir. I shall therefore first present my readers with a brief abstract of it, and then make such observations as subsequent inquiries suggest. In the researches which I made, at many different limes, upon the nature of the chlo- nde of lime, I generally sought to combine the information flowing from both synthesis and analysis; that is, I first converted a known portion of hydrate of lime into bleach- mg-powder, and then subjected this chloride to analysis. Two hundred grains of the atomic proto-hydrate of pure lime were put into a glass globe, which was kept coJd by immersion in a body of water at 50°. A stream of chlorine, after being washed in water of the same temperature in another glass globe. hydrate. The globe with the lime was detached from the rest of the apparatus from time to time, that the process might be suspended as soon as the augmentation of weight !^'t*^ T.n' *»^PP^"^^^^^" the 200 grains of hydrate, containing 15 19 of lime, had absorbed 130 grams of chlorine. By one analytical experiment, it was found that dilute muriatic acid expelled from 50 grains of the chloride, 20 grains of chlorine, or 40 per cent ; and by another from 40 grains, 16-25 of gas, which is 40-6 per cent. From the res^uum of the first 39-7 gramt of carbonate of lime were obtained by carbonate of ammonia ; from that of the second, 36-6 of ignited muriate of lime. ITie whole resulU are therefore as follows : — Chlorine - - Lime- - - - Water Synthesis. 1st Analysis. Sd Analysis. Mean 39-39 4600 14-60 40-00 44-74 15-26 40-62 46-07 13-31 40-31 45-40 14-28 10000 100-00 100-00 100-00 tr 408 CHLORIDE OF LIME. Though the heat generated by the action of the dilute acid had earned off m the analytical experiments a small portion of moisture with the chlorine, yet their accordance with the synthetic experiment is sufficiently good to confirm the general results. The above powder appears to have been a pure chloride, without any mixture of munate. But it exhibits no atomic constitution in its proportions. ,, , ^, j To 200 grains of that hydrate of lime 30 grams of water being added, the powder was subjected to a stream of chlorine in the above way, till saturation took place. Its increase of weight was 150 grains. . . ^ ^x. It ought to be remarked, that in this and the preceding experiment, there was no appreciable pneumatic pressure employed to aid the condensation of chlorine. In the last case, we see that the addition of 30 grains of water has enabled the lime to absorb 20 grains more of chlorine, being altogether a quantity of gas nearly equal to that of the dry lime. Thus, an atom of lime seems associated with seven ninths of an atom of chlorine. Analysis by muriatic acid confirmed this composition. It gave Chlorine • 89-5 — 51 '8 cubic inches. Lime - 39-9 Water - 20*6 100-0 A great variety of apparatus has been at different times contrived for favouring the combination of chlorine with the slaked lime for the purposes of commerce. One of the most ingenious forms is that of a cylinder, or barrel, furnished with narrow wooden shelves within, and suspended on a hollow axis, by which the chlorine was admitted, and round which the barrel was made to revolve. By this mode of agitation, the lime-dust, being exposed on the most extensive surface, was speedily impregnated with the gas, to the requisite degree. Such a mechanism I saw at MM. Oberkampf and Widmer's cele- brated /aftnaw de toilcs peintes, at Jouy, in 1816. But this is a costlv refinement, in- admissible on the Urgest scale of British manufacture. The simplest, and, in my opinion, the best construction for subjecting lime-powder to chlorine, is a large chamber 8 or 9 feet hi-'h, built of silicious sandstone, having the joints of the masonry secured with a cement composed of pitch, resin, and dry gypsum in equal parts. A door it fitted into it at one end, which can be made air-tight by strips of cloth and clay-lute. A window on each side enables the operator to judge how the impregnation goes on by the color of the air, and also gives light for making the arrangements within at the commencement of the process. As water lutes are incomparably superior to all others, where the pneumatic pressure is small, I would recommend a large valve or door on thij principle to be made in the roof, and two tunnels of considerable width at the bottom of each side wall. The three covers could be simultaneously lifted off by cords passing over a pulley, without the necessity of the workman approaching the deleterious gas, when the apartment is to be opened. A great number of woosed. I have tried the indigo test in many ways, but never could confide in it. The sulphu- ric solution of indigo is very liable to change by keeping, and thus to lead to erroneous results. The method of testing the chlorides by green sulphate of iron, described imder bleaching, is in my opinion preferable to the above. M . Gay Lussac has rece.itly proposed another proof of chlorine, founded on the same pnnciple as that by green vitriol, namely, the quantity of it requisite to raise a metallic substance from a lower to a higher stage of oxydizement. He now prescribes as the preferable plan of chlorometry, to pour very slowly from a graduated glass tube, % standard solution of the chloride, to be tested upon a determinate quantity of arsenious acid dissolved in muriatic acid, till the whole arsenious be converted into the arsenic acid- The value of the chloride is greater the less of it is required to produce this effect It is easy to recognise, by a few drops of solution of indigo, the instant when all the arsenious acid has disappeared ; for then the blue tint is immediately effaced, and can- not be restored by the addition of a fresh drop of indigo solution. In graduating the arsenical chlorometer, M. Gay Lussac takes for his unity the de- colouring power of one volume of chlorine of 32<> Fahr., and divides it into 100 parts. Suppose that we prepare a solution of chlorine containing its own volume of the gas, and an arsenious solution, such that, under a like volume, the two solutions shall recipro- cally destroy each other. Let us call the first the normal solution of chlorine, and the second, the normal arsenious solution. "We shall fix at 10 grammes the weight of chlo- ride of lime subjected to trial ; and dissolve it in water, so that the total volume of the solution shall be a litre (1000 grammes measure,) including the sediment If we take a constant volume of this solution, 10 centimetres cube (10 gramme measures,) for ex- ample, divided into 100 equal parts, and pour into it gradually the arsenious solution r (measured by like portions), till the chlorine be destroyed, the bleaching power will be proportional to the number of portions of the arsenious solution, which the chloride shall have required. If the chloride has destroyed 100 portions of the arsenious solution, its title will be 100 ; if it has destroyed 80 portions, its title will be 80, Ac, and so forth. On pounng the acidulous arsenious solution into the chloride of lime, this will become very acid ; the chlorine will be emitted abundantly, and the proof will be quite incorrect. If, on the contrary, we pour the solution of the chloride of lime into the arsenious solu- tion, this evil will not occur, since the chlorine will always find plenty of arsenious acid to act upon, whatever be the dilution of the one or the other ; but in this case, the stand- ard of the chlorine is not given direcily, as it is in the inverse ratio of the number of portions which are required to destroy the measures of the arsenious solution. If 50 portions of the chloride have been required, the proof will be lOOX^— — ^=200°- if 200 have been required, the proof will be 100X-^g=50°, &c. This evfl**is not, however, ▼ery serious, since we have merely to consult a table, in which we can find the proof corresponding to each volume of the chloride employed for destroying the constant measure of the arsenious solution. The arsenious solution should be slightly tinged with sulphate of indigo, so as to show, by the disappearance of the color, the precise point or instant of its saturation with chlorine, that is, its conversion into arsenic acid. If the arsenious acid be pure, the normal solution may be made directly by dissolving 4*439 grarnmes of it in muriatic acid (free from sulphurous acid), and diluting the solution till it occupies one litre, or 1000 grammes measure, jinnales de Chimie et Phvsiaue LX. 225. * ^ ' CHOCOLATE is an alimentary preparation of very ancient use in Mexico, from which country it was introduced into Europe by the Spaniards in the year 1520, and by them long kept a secret from the rest of the world. Linnaeus was so fond of it' that he gave the specific name, theobroma^ food of the gods, to the cacao-tree which produced it. The cacao-beans lie in a fruit somewhat like a cucumber, about 5 inches long and 3| thick, which contains from 20 to 30 beans, arranged in 5 regular rows with parti- tions between, and which are surrounded with a rose-colored spongy substance like that of water-melons. There are fruits, however, so large as to contain from 40 'to 50 beans. Those grown in the West India islands, Berbice and Demarara, are much smaller, and have only from 6 to 15; their development being less perfect than in South America. After the maturation of the fiuit, when their green color has chan^^ed to a dark yellow, they are plucked, opened, their beans cleared of the marrowy sub- stance, and spread out to dry in the air. Like almonds, they are covered with a thin skin or husk. In the West Indies they are immediately packed up for the market when they are dried ; but in the Caraccas they are subjected to a species of slight fer- mentation, by putting them into tubs or chests, covering them with boards or "stones and turning them over every morning, to equalize the operation. They emit a good deal of moisture, lose the natural bitterness and acrimony of their taste by this process as well as some of their weight. Instead of wooden tubs, pits or trenches dug in the ground are sometimes had recourse to for curing the beans ; an operation called earthine (terrer). They are lastly exposed to the sun, and dried. The latter kind are reckoned the best ; being larger, rougher, of a darker brown color, and, when roasted, throw off their husk readily, and split into several u-regular fragments ; they have an agreeable mild bitterish taste, without acrimony. The Guiana and West India sorts are "smaller flatter, smoother-skinned, lighter-colored, more sharp and bitter to the taste. They answer best for the extraction of the butter of cacao, but afford a less aromatic and agreeable chocolate. According to Lampadius, the kernels of the West India cacao beans contain, in 100 parts, besides water, 53' 1 of fat or oil, 16-7 of an albuminous brown matter, which contains all the aroma of the bean, 10-91 of starch, 7| of gum or mucilag^ 0-9of lignine, and 201 of a reddish dye stuff somewhat akin to the pigment of cochineal The husks form 12 per cent of the weight of the beans ; they contain no fat V t ^^^^^^^ hgnine, or woody fibre, which constitutes half their weight, thev yield a light brown mucilaginous extract by boiling in water. The fatty matter is of the con- sistence of tallow, white, of a mild agreeable taste, called butter of cacao, and not apt to turn rancid by keeping. It melts only at 122° Fahr., and should, therefore, make t')ler- able candles. It is soluble in boiling alcohol, but precipitates in the cold. It is obtained by exposing the beans to strong pressure in canvas bags, after they have been steamed or soaked in boiling water for some time. From 5 to 6 ounces of butter may be thus obtained from a pound of cacao. It has a reddish tinge when first expressed, but It becomes white by boiling with water. The beans, being freed from all spoiled and mouldy portions, are to be gently roasted over a fire in an iron cylinder, with holes in its ends for allowing the vapours to escape : the apparatus being similar to a coffee-roaster. When the aroma begins to be well developed, the roasting is known to be finished; and the beans must be turned out cooled, and freed by fanning and sifting from their husks. The kernels are then W II I i: ii iH4. II 41« CHOCOLATE. to be converted into a paste, either by trituration ma ^^J^^l^^^ff^^ ^ILLuy by the following ingenious and powerful machine The «^«««^^,*\P^^J..*^*y'"*"y iZprance a little vanilla incorporated with it, and ^«o^«f jf f^^nd Inl a haK of which varies from one-third of its weight to equal part^ For a pound ^^^ ^^aH ol cacao, one pod of vanilla is sufficient, Chocolate paste improves "»jf« A^^^ ^^J keeping, and should therefore be made in large quantities at a time. But the roastea beans soon lose their aroma, if exposed to the air. C CI czn ^p I . I jnn cun m m ruL ] Fi<'. 357 represents the chocolate mill. Upon the sole a, made of marble, six conical rollers b b, are made to run by the revolution of the upright axis or shaft q, dnven bv the agency of the fly wheel e and bevel wheels i k. The sole A rests upon a strong iron plate! which is heated by a small stove, introduced at the door h. The wooden frame work r, forms a ledge, a few inches high, round the marble slab, to confine the cocoa ia the act of trituration, c is the hopper of the mill through which the roasted beans are introduced to the action of the rollers, passing first into the flat ▼esse! p, to be thence evenly distributed. After the cacao has received the first tritura- tion, the paste is returned upon the slab, in order lo be mixed with the proper quantity ofsisar, and vanilla, previously sliced and ground up with a little hard sugar. When the chocolate is sufficiently worked, and while it is thin with the heat and trituration. It must be put carefully into the proper moulds. If »"tf?^»ced too warm, it will be apt to become damp and dull on the surface ; and, if too cold, it will not take the proper form. It must be previously well kneaded with the hands, to ensure the expulsion of everv air bubble. . . .,^„ __. In Barcelona, chocolate mills on this construction are very common, t>ut they are turned bv a horse-dn set to work in the under story, corresponding to H in the aDove figure. The shaft g is, in this case, extended down through the marble slab, and is surrounded at its centre with a hoop to prevent the paste coming into contact with it Each of these horse-mills turns out about ten pounds of fine chocolate in the hour, from a slab two feet seven inches in diameter. • <. j r *v Chocolate is flavoured with cinnamon and cloves, in several countries, instead ot the more expensive vanilla. In roasting the beans the heat should be at first ver>' slow to eive time to the humidity to escape; a quick fire hardens the surface, and injures the process. In putting the paste into the tin plate, or other moulds it must be weU shaken down to insure its filling up all the cavities, and giving the sharp and polished impression so much admired by connoisseurs. Chocolate is sometimes adulterated with starch : in which ease it will form a pasty eonsistenced mass when treated with boilimr waiter. The harder the slab upon which the beans are triturated, the better ; and thence porphyry is far preferable to marble. The grinding rollers of the mill should be made of iron, and kept very clean. i • v About eight years ago, samples of chocolate were sent to me for analysis by order of the Lori of the Admiralty. It was made at the victualling-yard Deptford for the use of the Royal Navy, by the government chocolate mills, where about CHOCOLATE. 417 400 tons are annually prepared, to be distributed to the sailors and convicts at the rate of an ounce daily, and to be used at their breakfast. After taking the said choco- late for some time, men in several ships complained of its occasioning sickneae. vomiting purging, and more serious maladies, terminating in a few cases fatally I examined it with great care, but could find no injurious ingredient in it, and no chemical alterations from the beans of the Guyaquil coco from which it was manu- factured. But I observed that it consisted of gritty grains, from very imperfect tri- turation or miHing ; that these grains were quite immiscible with water, like so much tone gravel ; that they contained many sharp spicule of the coco-bean husks, and that hence, when swallowed, they were calculated to form mechanically irritating lodg- Zlltr ^*^\^^"««« coats of the stomach and bowels, whereby they could produce the ^n^\i ^^^""^ certified bj several naval surgeons. It was, moreover, obvious that, from the insoluble condition of the chocolate, it could be of little use as an article of lood or as a demulcent substitute for milk, and that, in fact, three-fourths of it were, on this account, an ineffective article of diet, or were wasted Having reported these results and opinions to the Lords of the Admiralty, they were pleased after a few weeks' consideration, to request me to go down to the vi^ tualJinff-yard at Deptford and superintend the preparation of a quantity of chocolate in the best manner I could with the means there provided. I accordingly repaired thither on the 13th September, 1842, and experienced the utmost courtesy and co- operation from Sir John Hill, the Captain Superintendent, and his subordinate officers: Ihe coco-beans had been hitherto milled, after a slight roasting upon the sole of an oat-kUn, along with their husks. As I was satisfied, from analysis, that the husks were no better food than saw-dust, and that they might cause irritation by their minute spiculae left after grinding between rotating millstones, I set about a plan for shelling them, but could find no piece of apparatus destined for the purpose. There was, how- ever, a pea-shelling mill, which had been used only for one day some years before and Had stood ever since idle* which, on being cleaned and having its millstones placed at a proper distance, was found to answer pretty welL The beans for experiment, to the amount of 6 cwt, had been previously roasted, under my care, at a well-regulated heat, with much stirring, in the oat-kiln; and, on being cold, were run through the siieliing mill, which was put in communication with the fanners of the flour mUL 15y this arrangement, the coco-beans were tolerably shelled, and the kernels separated trom their scaly husks. The weighings were accurately made. 6 cwt. of the Guyaquil coco Lost in roasting shells waste Remained for milling 672 lbs. 555 On the 14th September I made a report to the Lords of the Admiralty upon the experiments of the 13th, of which the following is an outline. After describing the pains taken to regulate the roasting temperature, and to equalize the effect upon the beans by moving them occasionally by a rake, I stated that the oat-kiln was not well adapted to the purpose of roasting the coco, because it was impossible to turn the beans regularly and continuously during the process, so that they could not be equally roasted and because it was an unwholesome operation for the workmen, who must go into a chamber filled with noxious gases and fumes, to use the rakes. When the door of the kiln was shut, to allow the burned air from the fire below to draw up through it, mischief might be done to the stratum of coco on the sole, and when the door was again opened to permit a person to go in and stir, time and heat were wasted in replenishing the chamber with fresh air. I understood that a revolving-cylinder-roasting machine had been made by Messrs. Rennie for the chocolate process at Deptford; but, for reasons unknown to me, it had never been employed. The diminution of weight by roasting and sheUing may be estimated at about 11 per cent A part of this loss is moisture, which should be completely expeUed, to prevent its causing the chocolate to become mouldy at sea. But a part of the defal- cation was also due to some of the coco remaining in the crevices of the pea-splitting mill and the fanners, which would not be observable if these were in constant employ- ment. I think, therefore, that the roasted kernels may be estimated in general at 85 per cent of the raw beans. J^g. 368 represents the chocolate mills at the victualling-yard, Deptford, as mounted r * ? i?^v^°"°? *^** ^" *° '^*''" "^'"^ ^'^Pt ^tter at sea than tha split peas, and thej were also pra- terred by the sailors in their natural state. *- r » j r Vol. L 8H I !! t 418 CHOCOLATK CHOCOLATE. bv the celebrated engineers, Messrs. Rennie. There are four double mill-stonet A. B. c D each three feet in diameter, of which the nether rests upon a bed of cast iron, like a drum-head, kept at the temperature of about 220° by the admission of steam to the case below. Over each mill there is a feeding-hopper 1, 2, 3, 4, in conamu- nication by the pipes 6, 6, 1, 8, with the general reservoir e, charged «Pon the floor above with cocoa through the funnel placed over it The vertical shafts which turn these mnis are marked f, g, h, l; they are moved by the train of bevel-wheels above, which are driven by an arm from the main shaft of the steam engine. JiAch miU can, of course, be thrown in and out of geer at pleasure. At i, i, i, i, the discharge-spout 419 U Rhown which pours out the semi-fluid hot chocolate into shallow cylindrical tm pan^ ^mibTe if contaiUg about nine pounds of chocolate each. These four mil s are capable ;?Werting upwards of a ton of coco into good chocolate in a day. on the system of double triJufatU which I adopted, and two tons on the former rough plan I found th^t the two stones of each mill had been placed so far asunder as would allow entire Ws t^ pl^ through, as spurious chocolate, at one operation ; but the chocolate thus Sar^e^Tas in a fe^y gritty state, whereas good chocolate m the liquefied state should be smooth and plastic between the fingers, and spread upon the tongue without leaving any granular particles in the mouth. To obtain such a result^ I divided the milling into two steps ; for the first, two pairs of the stones, a and c^ were set as close together as for a paint mill (which they closely resemble), and the other two pairs, b and d, were left at their ordinary distance. The paste obtained from the first set was trans^ ferred, while nearly liquid, into the hoppers of the second pairs, from which it issued at the spouts as thin and smooth as honey from the comb. In subserviency to these ex- periments, I made an analysis of the Guyaquil coco, which I found to be composed a« Concrete fat or butter of coco, dissolved out by ether Brown extractive, extractible by hot water, after the operation of ether Ligneous matter, with some albumine - - . . . Shells Water Loss -.--..._ 87 10 80 14 6 3 100 Tlie solid fat of the coco should be most intimately combined by milling with the extractive albumine, and ligneous matter, in order to render it capable of forming an emulsion with water ; and, indeed, on account of the large proportion of concrete fat in the beans some additional substance should be introduced to facilitate this emulsive union of the fat and water. Sugar, gum, and starch or flour are well adapted for this purpose. Under this conviction, I employed in the first of these trials at Deptford, made with one-half of the above roasted keniels = 277i lbs., 6 per cent of sugar, which waa first mixed upon a board with shovels, and the mixture was then put progressively into tlie hoppers of the two mills b and d. The paste which ran out of their spouts was immediately poured into the hoppers of a and c, from which it flowed smooth and very thin into the concreting pans. The sugar supplied to me was exceedingly moist^ whereas it ought to be dry, like the bag sugar of the Mauritius. The other half of the coco kernels was milled alone once by the ordinary mills b and d. I sub- jected next day samples of these two varieties of chocolate to the following examina- tion, and compared them with the sample of chocolate as usually made at Deptford, as also with a sample of chocolate sold by a respectable grocer in London. A like quantity of these four samples was treated with eight times its weight of boiling water, the diffusion well stirred, and then left to settle in a conical wineglass. Of the ordi- nary Deptford coco, four-fifths rapidly subsided in coarse grains, incapable of forming any thing like an emulsion with water, and therefore of little or no avail in making a breakfast beverage. 1. The single-milled chocolate made under my direction formed a smoother emul- sion than the last, on account of the absence of the coco husks ; but its particles were giitt}', and subsided very soon. 2. The sugar double-milled chocolate, on the contrary, formed a milky-looking emulsion, which remained nearly uniform for some time, and then let fall a soft mucilaginous deposit, free from grittiness. 3. The shop chocolate formed a very indifferent emulsion, though it was well milled, because it contained evidently a large admixture of a coarse branny flour, as is too generally the case. I have given small samples of the above No. 2. chocolate to various persons, and they have considered it superior to what is usually sold by our grocers. The presence of dry sugar in chocolate would also give it a conservative quality at sea, and prevent it from getting musty. The Lords of the Admiralty, after seeing the above two samples of chocolate and my report thereupon, were, about six weeks afterwards, pleased to request me to make at Uieir victualling-yard further experiments in the preparation of chocolate ; and they indicated two modes, one of milling twice with the husks, and another of milling twice without the husks ; permitting me, at the same time, to mill a portion of the kernels with 10 per cent of sugar, and a second portion of the kernels with 5 per cent of sugar and 6 per cent of the excellent flour used in making the biscuits for the royal navy. On the 24th October, 1842, I accordingly performed these experiments upon 12 cwt^ of Guyaquil coco as carefully roasted as possible on the kiln. The loss in drying and slightly roasting the 1344 lbs. of beans was 6 per cent Ist experiment, 212 lbs. of roasted coco, milled twice with the husks, produced of chocolate --.-__ 209 lbs 2d experiment, 191 lbs. ditto, milled twice without husks - - 189 8H2 t 420 CHROMATES. 'i 3d experiment, 191 lbs. kernels, milled once along with 19 lbs. of sugar =210 lbs. ------■" "'" 4th experiment, 573 lbs. of kernels, milled twice along with 68 lbs. of flour and 34 of sugar = 675 : , ' " , ' ^i ' ?* r. Sample cakes of these four varieties of chocolate were subsefjuently sent to me fof examination and report I found that the chocolate milled twice with the flour and ms&T formed a complete emulsion with hot water, bland and rich, like the best milk, but the other three were much inferior in this respect Sugar alone, with proper milling would serve to give the kernels of well roasted coco a perfect emulsive pr<^ perty Instead of merely miUing with rotary stones, I would prefer, for the second or finishing operation, a levigating mill, in which rollers would be rolled either back- wards and forwards, or, when slightly conical, in a circular direction, over a plane metallic, marble, or porphyry, slab as is now, indeed, very generally practised by the trade. The coco-beans should be weU selected, without musty taint, and possessed of a fine aroma, like the best of that imported from Trinidad. There is a great deal of very coarse coco and chocolate on sale in London and in the provincial towns of the United Kingdom. . . Fig. 359. is an end view of one of the chocolate mills with its mitre-gearing. I consider the gritty chocolate hitherto 359 made at Deptford as a very bad substitute for the chocolate which was made from coco by the sailors themselves with a pestle and mortar. . In 1840 the coco cleared for consumption in the United Kmg- dom was: — British plantation - Foreign Coco-nut husks and shells Chocolate and coco paste 2,041,492 lbs. 186 753,580 2,066 Of the cocoa-nut shells, 612,122 lbs. were consumed in Ireland! and less than 4000 lbs. of coco. ^ Of coco, 726,116 lbs. were consumed in her Majesty s navy. How scurvily are the people of Ireland treated by their own grocers ! Upwards of 600,000 lbs. of worthless coco husks served out to them along with only 4000 lbs. of coco-beans ! The quantity of coco imported in 1850 amounted to 4,478,252 cwts. and in 1851 to 6,773,900 cwts. ; the entries for home consumption were 3,103, 926 and 3,024,338 cwts. ; the re-exports were 1,443,363 and 1,543,456 cwts. ; and the erossamountofduty 16,059/. and 15,778/. respectively. .^^ ^^ ^ . ^ ^ CHROMATES, saline compounds of chromic acid with the basis, bee I^hro- ^^Messrs. Swindell and Co. obtained a patent in November, 1850, for obtaining copper, silver, and chrome, from their ores. j- ♦ ♦u- 1st To obtain copper and silver, or copper only, from their ores, accordmg to this invention, the ores are first roasted to drive off the sulphur, and convert the metals to the state of oxides, after which the prepared ores are placed in tanks^and a solution of ammonia or its salts, of a strength of about 0-980, pumped on in sufficient quantity to saturate them. This solution is removed at the expiration of twelve to twenty-four hours, and will be found saturated with the raetalUc oxides, which are to be dissolved in boiling water and precipitated— the silver by hydrochloric, and the copper by hvdrosulphuric acids or otherwise. . ^ i • i • • j 2nd. The ore from which zinc is obtained is the native sulphuret, which is mixed with about its own weight of common salt (for which muriate of potash, or of any earth, may be substituted), and exposed in a calcining furnace to a slow protracted heat, until all the sulphur present is converted into sulphuric acid. The products ot this operation will be sulphate of soda, muriate of zinc, and muriate of iron, which are to be dissolved out in boiling water, and the two latter precipitated by bme^ or other means, after the sulphate of soda has been separated in the usual manner. The oxide of zinc when thus precipitated, may be smelted in the usual way. , .• , .., In treating chromium (chromite of iron), the ore is pulverized and mixed with common salt, muriate of potash, or hydrate of lime, and exposed in a reverberatory furnace to a red or even a white heat the mixture being stirred every ten or fifteen minutes, and steam at a very elevated temperature introduced during the operation, natil the desired effett is obtained, which may be ascertained by withdrawmg a portion • Thi« small excess proceeded from a residue of the last experiment. CHROMIUM, 421 from the flimace and testing it, as customary. The products of this operation are finally treated in the manner usual for chromic and bichromic salts. The mixture of chromium and common salt produces chromate of soda, the greater portion, or perhaps all of the iron contained in the chromium being absorbed by the hydrochloric acid evolved from the salt and carried off in the form of sesquichlonde of iron. From the first mixture is manufactured pure bichromate of soda, which, by the addition of hydrochloric acid, may be converted to chlorochromate ; and from the last, or lime mixture, is produced a chromate of that earth, fiom which, by the addition of soda or potash, there may be obtained a compound salt, which, with those previously mentioned, may be advantageously employed in the operation specified in the title. CHROMIC ACID. To a boiling saturated solution of bichromate of potash, add as much oil of vitrol as will convert the potash into a bisulphate. Let the whole cool, and be then washed with a little water, and stirred, when the liquid decanted from the granular mass will be nearly pure chromic acid. The solution of chromic acid in oil of vitriol is preferable as an oxidizing agent to every other at present known. See Chromium. CHROMIUM. The only ore of this metal, which occurs in sufl5cient abundance for the purposes of art, is the oclohedral chrome-ore, commonly called chromate of iron, though it is rather a compound of the oxydes of chromium and iron. The fracture of this mineral is uneven ; its lustre imperfect metallic ; its color between iron-black and brownish-black, and its streak brown. Its specific gravity, in the purest state, rises to 4*5 ; but the usual chrome-ore found in the market varies from 3 to 4. According to Klaproth, this ore consists of oxyde of chromium, 43 ; protoxide of iron, 34*7 ; alumina, 20-3; and silica, 2; but Vauquelin's analysis of another specimen gave as above, respectively, 55-5, 33, 6, and 2. It is infusible before the blowpipe ; but it acts upon the magnetic needle, after having been exposed to the reducing smoky flame. It is entirely soluble in borax, at a high blowpipe heat, and imparls to it a beautiful green color. Chrome-ore is found at the Bare Hills, near Baltimore, in Maryland ; in the Shetland Isles, Unst and Fetlar; the department of Var, in France, in small quantity j and near Portsoy, in Banffshire ; as also in Silesia and Bohemia. The chief application of this ore is to the production of chromate of potash, from which salt the various other preparations of this metal used in the arts are obtained. The ore, freed, as well as possible, from its gangue, is reduced to a fine powder, by being ground in a mill under ponderous edge-wheels, and sifted. It is then mixed with one third or one half its weight of coarsely bruised nitre, and exposed to a powerful heat, for several hours, on a reverberatory hearth, where it is stirred about occasionally. In the large manufactories of this country, the ignition of the above mixture in pots is laid aside, as too operose and expensive. The calcined matter is raked out, and lixiviated with water. The bright yellow solution is then evaporated briskly, and the chromate of potash falls down in the form of a granular sail, which is lifted out from time to time from the bottom with a large ladle, perforated with small holes, and thrown into a drain ing-box. This saline powder may be formed into regular crystals of neutral chromate of potash, by solution in water and slow evaporation ; or it may be converted into a more beautiful crystalline body, the bichromate of potash, by treating its concentrated solution with nitric, muriatic, sulphuric, or acetic acid, or, indeed, any acid exercising a stronger affinity for the second atom of the potash than the chromic acid does. Bichromate of potash, by evaporation of the above solution, and slow cooling, may be obtained in the form of square tables, with bevelled edges, or fiat four-sided prisms. They are permanent in the air, have a metallic and bitter taste, and dissolve in about one tenth of their weight of water, at 60® F. ; but in one half of their weight of boiling water. They consist of chromic acid 13, potash 6 ; or, in 100 parts, 68-4 -f 31'6. This salt is much employed in calico-printing and in dyeing ; which see. Chromate of lead, the chrome-yellow of the painter, is a rich pigment of various shades, from deep orange to the palest canary yellow. It is made by adding a limpid solution of the neutral chromate (the above granular salt) to a solution, equally limpid, of acetate or nitrate of lead. A precipitate falls, which must be well washed, and care- fully dried out of the reach of any sulphureted vapors. A lighter shade of yellow is obtained by mixing some solution of alum, or sulphuric acid, with the chromate, before p<(uring it into the solution of lead ; and an orange tint is to be procured by the addition of subacetate of lead, in any desired proportion. For the production of chromate of potash from chrome ore, various other processes have been recommended. The following formute, which have been verified in practice^ will prove useful to the manufacturers of this important article: — I. Two parts of chrome ore, containing about 50 per cent, of protoxyde of chromhun: One part of saltpetre. i '1 r I I 423 CHROMIUM. n. Foui parts of chrome ore, conUdning 34 per cent, of protoxyde of chromium. Two parts of potashes. One part of saltpetre. in. Four parts of chrome ore. — 34 — Two of potashes. Four tenths of a part of peroxyde of manganese. rV. Three parts of chrome ore. Four parts of saltpetre. Somrmanuflcturere have contrived to effect the conversion of the oxyde into an acid, and of course to form the chromate of potash, by the agency of potash alone, in a calcining furnace, or in earthen pots fired in a pottery kiln. , . , . i-«m» »nr« After lixiviating the calcined mixtures with water, if the solution be a tolerably pure chromate of potash, its value may be inferred, from its specific gravity, by the followmg table : — _ At specific gravity 1*28 it contains about 50 per cent, of the salt. 1-21 33 1-18 25 M5 SO M2 16 Ml 14 MO 12 In making the red bichromate of potash from these solutions of the yellow salt, nitne acid was at first chiefly used ; but in consequence of its relatively high price, sulphuric, muriatic, or acetic acid has been frequently substituted upon the great scale. There is another application of chrome which merits some notice here; that of itsgreca oxyde to dyeing and painting on porcelain. This oxyde may be prepared by decomposing, with heat, the chromate of mercury, a salt made by adding to nitrate of pi>3loxyde of mer- cury, chromate of potash, in equivalent proportions. This chromate has a fi»«c» ""«*«' red when pure : and, at a dull red heat, parts with a portion of its oxygen and its mercurial oxyde. From M. Dulong's experiments it would appear that the purest chromate of mercury is not the best adapted for preparing the oxyde of chrome to be used in porcelain painting. He thinks it ought to contam a little oxyde of manganese ;rd chr^ate of p'otash,^to afford a green color of a fine tint, especially for pieces that "e to receive a powerful heat. Pure oxyde of chrome preserves its color well enough in a muffle furnace ; but, under a stronger fire, it lakes a dead-leaf color. The creen oxyde of chrome has come so extensively into use as an enamel color tor porcelain, that a fuUer account of the best modes of manufacturing it must prove accept- able to many of my readers. , . • ii« That oxyde, in combination with water, called the hydrate, may be economiically prepared by boiling chromate of potash, dissolved in water, with half its weight of flowers of sulphur, till the resulting green precipitate ceases to increase, which imy be easily ascertained by filtering a little of the mixture. The addition of some potash accelerates the operation. This consists i^n combining the sulphur with the oxyge^ of Ae chromic acid, so as to form sulphuric acid, which unites with the potash of the chromate into sulphate of potash, while the chrome oxyde becomes a M'f «^^- /^" extra quantity of potash facilitates the deoxydizement of the chromic acid by the forma- "ron of hypoLlphfie and sulphuret of potash, both of which have ^ string ,^"^^»««; for oxy-en: For this purpose the clear lixivium of the chromate of potash is sufficiently pure, [hough it should hold some alumina and silica in solution, as it ?enera^^y do«» The hydrate may be freed from particles of sulphur by heating dilute sulphuric acid upon it, which dissolves it; after which it may be precipitated, in the stale ol a carbonate, by carbonate of potash, not added in excess. . i v • By calcininr a mixture of bichromate of potash and sulphur m a crucible, ehroipic acid is also decomposed, and a hydrated oxyde may be obtained; the sulphur being nartly converted into sulphuret of potassium, and partly into sulphuric acid (at the expense of the chromic acid), which combines with the rest of the potash into a sulphate. By careful lixiviation, these two new compounds may be washed away, ana the chrome green may be freed from the remaining sulphur, by a slight heat. Liebi*' and Wohler have lately contrived a process for producing a subchromate « lead of\ beautiful vermilion hue. Into saltpetre, brought to fusion in a crucible at a irentle heat, pure chrome yellow is to be thrown by small portions at a time. A stron- ebullit on takes place at each addition, and the mass becomes black, and con- Ss so whUe it is hot. The chrome yellow is to be added till little of the saltpetre remans uXomposed, care being taken not to overheat the crucible, lest the cotor Tf the mixture shbuld become brown. Having allowed it to settle for a few minutes, during which the dense basic salt falls to the bottom, the fluid part, consistmg ol CHROMIUM. 423 diromate of potash and saltpetre, is to be poured off, and it can be employed again it preparing chrome yellow. The mass remaining in the crucible is to be washed with iraler, and the chrome red being separated from the other matters, is to be dried after proper edulcoration. It is essential for the beauty of the color, that the saline solution should not stand long over the red powder, because the color is thus apt to become of a dull orange hue. The fine crystalline powder subsides so quickly to the bottom after every ablution, that the above precaution may be easily observed. As Chromic jicid will probably ere long become an object of interest to the calico printer, I shall describe here the best method of preparing it. To 100 parts of yellow chromate of potash, add 136 of nitrate of barytes, each in solution. A precipitate of the yellow chromate of barytes falls, which being washed and dried would amount to 130 parts. But while still moist it is to be dissolved in water by the intervention of a little Bitnc acid, and then decomposed by the addition of the requisite quantity of sulphuric Bcid, whereby the barytes is separated, and the chromic acid remains associated with the nitric acid, from which it can be freed by evaporation to dryness. On re-dissolving the chromic acid residuum in water, filtering and evaporating to a proper degree, 50 parts of chromic acid may be obtained in crystals. This acid may also be obtained from chromate of lime, formed by mixing chromate of potash and muriate of lime; washing the insoluble chromate of lime which precipitates, and decomposing it by the equivalent quantity of oxalic acid, or for ordinary purposes even sulphuric acid may be employed. Chromic acid is obtained in quadrangular crystiis, of a deep red color ; it has a very acrid and styptic taste. It reddens powerfully litmus paper. It is deliquescent in the air. When heated to redness it emits oxygen, and passes into the deutoxyde. When a little o€ it is fused along with vitreous borax, the compound assumes an emerald green color. As chromic acid parts with its last dose of oxygen very easily, it is capable in certain styles of calico priming of becoming a valuable substitute for chlorine, where this more powerful substance would not from peculiar circumstances be admissible. For this in- genious application, the arts are indebted to that truly scientific manufacturer, M. Daniel Kcechlin, of Miilhouse. He discovered that whenever chromate of potash has its acid set free by its being mixed with tartaric or oxalic acid, or a neutral vegetable substance, (starch or sugar for example,) and a mineral acid, a very lively action is produced, with disengagement of heat, and of several gases. The result of this decomposition is the active reagent, chromic acid, possessing valuable properties to the printer. Watery solutions of chromate of potash and tartaric acid being mixed, an effervescence is produced which has the power of destroying vegetable colors. But this power lasts no longer than the effervescence. The mineral acids react upon the chromate of potash only when vegetable eoloring matter, gum, starch, or a vegetable acid are present, to determine the disengage- ment of gas. During this curious change carbonic acid is evolved ; and when it takes l^ace in a retort, there is condensed in the receiver a colorless liquid, slightly acid, exhaling somewhat of the smell of vinegar, and containing a little empyreumalic oil. This liquid heated with the nitrates of mercury or silver reduces these metals. On these principles M. Koechlin discharged indigo blue by passing the doth through a solution of chromate of potash, and printing nitric acid thickened with gum upon certain spots. It is probable that the employment of chromic acid would supersede the necessity of having recourse in many cases to the more corrosive chlorine. The following directions have been given for the preparation of a blue oxyde of chrome. The concentrated alkaline solution of chromate of potash is to be saturated with weak sulphuric acid, and then to every 8 lbs. is to be added 1 lb. of common salt, and half a pound of concentrated sulphuric acid ; the liquid will now acquire a green color. To be certain that the yellow color is totally destroyed, a small quantity of the liquor is to have potash added to it, and filtered ; if the fluid is still yellow, a fresh portion of salt and of sulphuric acid is to be added ; the fluid is then to be evaporated to dryness, redissolved, and filtered ; the oxyde of chrome is finally to be precipitated by caustic potash. It will be of a greenish-blue color, and being washed, must be collected upon a filter. Chromate of Potash, ddulteration of, to detect. The chromate of potash has the power of combining with other salts up to a certain extent without any very sensible change in its form and appearance ; and hence it has been sent into the market falsified by very considerable quantities of sulphate and muriate of potash, the presence of which has often escaped observation, to the great loss of the dyers who use it so ex- tensively. The following test process has been devised by M. Zuber, of Miilhouse. Add a large excess of tartaric acid to the chromate in question, which will decompose it, and produce in a few minutes a deep amethyst color. The supernatant liquor will, if the chromate be pure, afford now no precipitate with the nitrates of barytes or silver ; whence the absence of the sulphates and muriates may be inferred. We must, however, use dilute solutions of the chromate and acid, lest bitartrate of potash be pre- cipitated, wliich will take place if less than 60 parts of water be employed. Nor must i i 1 V 11 4^4 CITRIC ACID. we test the liquid till the decomposition be complete, and till the colour verge rather towards the green than the yellow. Eight parts of tartaric acid should be added to one of chromate to obtain a sure and rapid result If nitrate of potash (saltpetre) is the adulterating ingredient, it may be detected by throwing it on burning coals, when deflagration will ensue. The green colour is a certain mark of the transformation of the chromic acid partially into the chrome oxide ; which is effected equally by the sulphur- ous acid and sulphuretted hydrogen. Here tliis metallic acid is disoxygenated by the tartaric, as has been long known. The tests which I should prefer are the nitrates of silver and baryta, having previously added so much nitric acid to the solution of the sus- pected chromate, as to prevent the precipitation of the chromate of silver or baryta. The smallest adulteration by sulphates or muriates will thus be detected. Chromium, Oxide of. — Mix intimately 45 parts of gunpowder with 240 parts of perfectly dry chromate of potash, and 35 parts of hydrochlorate of ammonia (sal am- moniac), reduce to powder, and pass through a fine sieve ; fill a conical glass or other mould with this powder, gently pressed, and invert so as to leave the powder on a porcelain slab of any kind. When set on fire at its apex with a lighted match, it will burn down to the bottom with brilliant coruscations. The black residuum, being elutriated with warm water, affords a fine bright green oxide of chromium. Chromium, green oxide of. — Ignite bichromate of potash with a quarter of its weight of flowers of sulphur, by projecting the mixture into a red hot crucible in small successive portions, stirring the pasty mass till the excess of sulphur is burnt off ; pul- verize the cooled mass, and wash with water till it affords no precipitate with chloride of barium or acetate of lead. The powder which remains on being gently dried is of a beautiful green color, and may be used as a pigment, or to prepare pure chromium. CINNA3AR; the native red sulphuret of mercury. It occurs sometimes crystallized in rhomboids ; has a specific gravity varying from 6*7 to 8-2 ; a flat conchoidal fracture ; is fine grained; opaque; has an adamantine lustre, and a color passing from cochineal to ruby red. The fibrous and earthy cinnabar has a scarlet hue. It is met with disseminat- ed in smaller or larger lumps in veins, which are surrounded by a black clay, and is asso- ciated with native quicksilver, amalgam, with iron-ore, lead-glance, blende, copper-ore, gold, &c. Its principal localities are Almaden in Spain, Idria in the Schiefergebirge, Kreranitz and Schemnitz in Hungary; in Saxony, Bavaria, Bohemia, Nassau, China, Ja- pan, Mexico, Columbia, Peru. It consists of two primes of sulphur, = 32-240, com- bined with one of mercury, = 202,863 ; or in 100 parts of 12-7 sulphur -\- 87-3 mercury. It is the most prolific ore of this meial ; and is easily smelted by exposing a mixture of it with iron or lime to a red heat in retorts. Factitious cinnabar is called in commerce Vermilion, which see, as also Mercury. CINNAMON. (Cannellej Ft. ; Zimmt, Germ.) Is the inner bark of the laums cinna- momum, a handsome-looking tree which grows naturally to the height of 18 or 20 feet, in Java, Sumatra, Ceylon, and other islands in the East Indian seas. It has been transplant- ed to the Antilles, particularly Guadaloupe and Martinique, as well as Cayenne, but there it produces a bark of very inferior value to the Oriental. Cinnamon is gathered twice a year, but not till after the tree has attained to a certain age and maturity. The young twigs yield a bark of better quality than the larger branch- es. The first and chief harvest takes place from April to August ; the second, from No- vember to January. After having selected the proper trees, all the branches more thaa three years old are cut off"; the epidermis is first removed with a two-edged pruning knife, then a longitudinal incision is made through the whole extent of the bark, and lastly, with the bluntest part of the knife, the true bark is carefully stripped off" in one piece. All these pieces of bark are collected, the smaller ones are laid within the larger, and in this state they are exposed to the sun, whereby in the progress of drying, they become rolled into the shape of a quill. These convoluted pieces are formed into oblong bundles of 20 or 30 lbs. weight, which are placed in warehouses, sorted and covered with mats. Good cinnamon should be as thin as paper, have its peculiar aromatic taste, without burning the tongue, and leave a sweetish flavor in the mouth The broken bits of cinnamon are used in Ceylon for procuring the essential oil by distillation. 445,367 lbs. of cinnamon were imported into this kingdom in 1835, of which 16,604 only were re- tained for internal consumption. CITRIC ACID. (Jcide citriquCy Fr. ; Citrwiensaure, Germ.) Scheele first procured this acid in its pure state from lemon juice, by the following process. The juice put into a large tub, is to be saturated with dry chalk in fine powder, noting carefully the quantity employed. The citrate of lime which precipitates, being freed from the supernatant foul liquor, is to be well washed with repeated affusion and decantation of water. For every 10 pounds of chalk employed, nine and a half pounds of sulphuric acid, diluted with six times its weight of water, are to be poured while warm upon the citrate of lime, and well mixed with it. At the end of twelve hours, or even sooner, the citrate will be all CIVET. 425 decomposed, dilute citric acid will float above, and sulphate of lime will be found at the bottom. The acid being drawn off, the calcareous sulphate must be thrown on a canvass filter, drained, and then washed with water to abstract the whole acid. The citric acid thus obtained may be evaporated in leaden pans, over a naked fire till it acquires the specific gravity 1-13 ; after which it must be transferred into another vea- sel, evaporated by a steam or water bath till it assumes a syrupy aspect, when a pellicle appears first in patches, and then over the whole surface. This point must be watched with great circumspection, for if it be passed, the whole acid runs a risk.of being spoiled by carbonization. The steam or hot water must be instantly withdrawn, and the con centrated acid put into a crystallizing vessel in a dry, but not very cold apartment At the end of four days the crystallization will be complete. The crystals must be drained, re-dissolved in a small portion of water, the solution set aside to settle its impurities^ then decanted, re-evaporated, and re-crystallized. A third or fourth crystallization may be necessary to obtain a colourless acid. If any citrate of lime be left undecomposed by the sulphuric acid, it will dissolve in the citric acid, and obstruct its crystallization, and hence it will be safer to use the slightest excess of sulphuric acid, than to leave any citrate undecomposed. There should " not, however, be any great excess of sulphuric acid. If there be, it is easily detected by nitrate of barytes, but not by the acetate of lead as prescribed by some chemical authors; because the citrate of lead is not very soluble in the nitric acid, and might thus be con- founded with the sulphate, whereas citrate of barytes is perfectly soluble in that test acid. Sometimes a little nitric acid is added with advantage to the solution of the coloured crystals, with the effect of whitening them. Twenty gallons of good lemon juice will afford fully ten pounds of white crystals of citric acid. Attempts were made both in the "West Indies and Sicily, to convert the lime and lemon juice into citrate of lime, but they seem to have failed through the diflSculty of drying the citrate for shipment. The cr^'stals of citric acid are oblique prisms with four faces, terminated by dihedral summits, inclined at acute angles. Their specific gravity is 1'617. They are unalter- able in the air. When heated, they melt in their water of crj'stallization ; and at a higher heat, they are decomposed. They contain 18 per cent of water, of which one- half may be separated in a dry atmosphere, at about 100° F., when the crystals fall into a white powder. Citric acid in crystals is composed by my analysis of carbon, 35 "8, oxygen 59*7, and hydrogen 45 ; results which differ very little from those of Dr. Front subsequently obtained. I found its atomic weight to be 8*375, compared to oxygen 1,000. I cannot account for Berzelius's statements relative to the composition of this acid. Citric acid in somewhat crude crjstals is emplo3'ed with much advantage in calico- printing. If adulterated with tartaric acid, the fraud may be detected by adding potash to the solution of the acid, which will cause a precipitate of cream of tartar. The manufacture of citric acid so closely resembles that of tartaric acid, that the makers of one commonly fabricate the other. The raw material in this case is pretty generally a black fluid, like thin treacle, which comes from Sicily, and is obtained by inspissating the expressed juice of the lemon, — the rind having previously been removed from the lemon for the sake of its essential oil. This black juice is impure citric acid, and re- quires to be treated with chalk, as practised with respect to the first operation on tartar ; by which means, an insoluble citrate of lime is formed ; and this, after being well washed with cold water, is decomposed by sulphuric acid ; and the solution, after undergoing the action of animal charcoal and proper evaporation, yields brownish crystals on cooling. These are re-dissolved, discoloured, and crystallized three or four times ere they can be sent into the market for citric acid is more tenacious of colouring matter than most of the other vegetable acids. At Nice, and in the South of France, a portion of chloride of lime is digested upon the citrate of lime, to bleach it prior to decomposition by sulphuric acid. For this purpose, the washed citrate is exposed in shallow vessels to the action of the sun's rays, covered by a weak solution of chloride of lime. In a few hours decolouration ensues ; and it is moreover stated that the mucilage which hangs about the citrate of lime, and impedes the subsequent crystallization of the acid, is in this way destroyed, and the number of re-crystaUizations requisite to give a saleable aspect to the citric acid thereby diminished. The use of chloride of lime for this purpose seems unknown, or, at least, is not practised in England. Of the samples of citric acid shown in the Great Exhibition, those from Howards and Kent of Stratford, Fontifex and Wood, of Millwall, and J. Huskisson, of Gray's Inn Road, were extremely beautiful ; and in respect to size and crystalline form surpassed anything exhibited in the French, Prussian, or Italian departments. CIVET. {Civette, Fr. ; Zibeth, Germ.) This substance approaches in smell to musk and ambergris ; it has a pale yellow colour, a somewhat acrid taste, a consistence Vou L 3 1 i III i! • > -' 1 -■ [ V.,. r '' 426 CLAY. like that of honey, and a very strong aromatic odour. It is the product of two small quadrupeds of the genus viverra {v. zibetha and v. civetta), of which the one inhabits Africa, and the other Asia. They are reared with tenderness, especially in Abyssinia. The civet is contained in a sac, situated between the anus and the parts of generation, in either sex. The animal frees itself from an excess of this secretion by a contractile movement which it exercises upon the sac, when the civet issues in a vermicular form and is carefully collected. The negroes are accustomed to increase the secretion by irritating the animal ; and likewise introduce a little butter, or other grease, by the natural slit in the bag, which mixes with the odoriferous substance, and increases its weight It is employed only in perfumery. According to M. Boutron-Chalard, it contains a volatile oil, to which it owes ita smell, some free ammonia, resin, fat, an extractiform matter, and mucus. It affords by calcination an ash, in which there are some carbonate and sulphate of potash, phosphate of lime, and oxide of iron. CLAY {Argile, Fr. ; Thon, Germ.) is a mixture of the two simple earths, alumina and silica, generally tinged with iron. Lime, magnesia, with some other colouring me- tallic oxides, are occasionally present in small quantities in certain natural clays. The different varieties of clay possess the following common characters : — 1. They are readily diflFusible through water, and are capable of forming with it a plastic ductile mass, which may be kneaded by hand into any shape. This plasticity exists, however, in very different degrees in the different clays. 2. They concrete into a hard mass upon being dried, and assume, upon exposure to the heat of ignition, a degree of hardness sometimes so great as to give sparks by col- lision with hardened steel. In this state they are no longer plastic with water, even when pulverised. Tolerably pure clays, though infusible in the furnace, become readily so by the admixture of lime, iron, manganese, independently of an immense home consumption, our exports of earthenware last year amounted to a miUion sterling ? Had the clays of this country been of a tolerably uni- form composition, like some of those in China and on the continent, of course mere practice would long ago have enabled our potters to produce articles of the highest quality. But surely this is a sorry compliment to men surrounded by all the resources of science and capital Where there is no difficulty there can be but little merit, and still less profit It is the great glory of British enterprise and industry to despise so low and facile a position. Our manufacturers must meet and overcome the trivial impediments connected with variations in the clay they purchase, and, by properly ad- justing the other materials (so as to bring on exactly the due amount of vitrification needed in the body of the ware), produce, from any kind of clay, articles identical with those which other nations fabricate from the very finest clays only. With the pro- digious commercial and other advantages possessed by Great Britain, the world at large ought to expect this at our hands, and not the sub-mediocre workmanship displayed iu the Great Exhibition. Before quitting this subject, a few remarks upon the substances used in the formation of glazes may not be inappropriate. The million is still supplied with earthenware, the glaze of which contains lead, and is, consequently, dangerous to healtli, though, when well burned on, this danger is greatly diminishec^ from the increased insolubility of the silicate of lead in weak acids. It is, however, an objectionable mode of glazing earthenware, and requires to be watched with caution, more especially where borax is used at the same time, for the borate of lead is more easily acted on than the silicate. It has been lately suggested that oxide of zinc would form a sufficiently fusible compound with silica, and is cheap enough to supplant oxide of lead in the glazing of common earthenware. The latter assertion is undoubtedly true, and, although we entertain some suspicions as to the easy fusibility of silicate of zinc, yet this is precisely one of those problems which, from their important sanitary bearing, deserve immediate investigation. On the continent a very pure kind of felspar, mixed probably with a little carbonate of baryta and oxide of tin, forms the only glaze used upon porcelain and the china vessels intended for chemical purposes. Tliis glaze is practically perfect It is so hard as to withstand the attack of a file, and it resists the action of the strongest acids and alkalis at all temperatures below 300° Fahr.-— the hydrofluoric acid and its salts alone ex- cepted. In the French, Saxon, and Prussian departments of the Crystal Palace, there were several good specimens which illustrated the value of this kind of glaze Amongst the English goods— and chiefly those fi-om Staffordshire — were a variety of articles made in what is termed Parian, a compound, the unfitness of which for statuary purposes we now briefly animadvert upon, with reference however only to its employment in the higher branches of Decorative Art. The employment of this ma- tenal, or indeed any other form of alumina where sharpness and symmetry are wanted, cannot be sufficiently condemned, since it is totally contrary to the natural properties of alumina, and betrays infinite ignorance regarding first principles. The philosophical mind of Wedgewood would have revolted at so palpable an absurdity ; for not alone was he well acquainted with the continuous contractility of aluminous compounds, but» taking advantage of that knowledge, he was able to construct an instrument for measuring high degrees of heat> which, although not rigidly perfect, is at this day still I f! m 432 COAL. found the only available guide for furnace operations on a large scale. And the value of this instrument or pyrometer, as it is termed, depends upon the fact, that the longer and higher the temperature to which clay is exposed, the smaller it becomes. Isow, bearing in mind that earthenware is an extremely bad conductor of heat, let us imagine the Greek Slave, for example, correctly modelled in clay or Parian, and subjected to the heat of a porcelain furnace. The smaller portions of the figure, as the nose, eye- lids, fingere, la .... Anthracite, Jones and Co. • 9-35 11-301 13 563 497 1932 9-46 12-554 14-593 0225 0-990 Old Castle Fiery Vein Ward's Fiery Vein - Binea - • - - . 8-94 10-601 14-936 1590 6-175 9-40 . 14-614 1-238 4 -SOS 9-94 11-560 15-093 1586 6-741 Llaogenneck • • • 886 10-599 14-260 1299 5-044 Pontrepoth - - - - 8-72 10-873 14-838 0-218 0-848 Pontrefeilin ... 636 10-841 13787 a trace — Powell's Duffryn 10149 11134 15092 1-76 6-835 Mynydd Newydd Three Quarter Rock Vein - 9-52 9-831 14-904 1-808 7-340 684 7-081 13-106 1299 5-044 Cwm Frood Rock Vein 8-70 8-628 14-788 1-347 5232 Cwm Nauty Gros Resulven ... 8-42 8-243 13-932 1-919 7-448 9-53 10-234 13-971 1-675 6-505 Ponlypool .... Bedwas ... 7-47 6-144 14-295 1639 6-364 9-79 8-897 14-841 1-748 6-768 EbbwVale • - - 10*21 10-441 15 635 2-622 10 182 Forth Mawr Rock Vein 7-53 6-647 12-811 1-554 6-033 Coleshill .... 80 6-468 12-799 1.785 6930 Dalkeith Jewel Seam 708 6-239 12-313 1-214 471 Dalkeith Coronation - 7-71 6-924 12-772 a trace — Wallsend Elgin - 8-46 6 560 13-422 1-712 6-647 Fordel Splint ... 7-56 6.560 13817 1-372 5327 Grangemouth ... 7-40 7-292 13-692 1-639 6-364 Broomhill .... 7-30 7-711 14663 2-234 8674 Park End Lydney Slievardagh ... 8 52 6-567 13-257 1-477 9617 9-85 10-895 12-482 0-279 1-084 of carbon. There is, however, clearly a design throughout this report to extol the anthracite coals at the expense of the bituminous ; and, if Messrs. de la Beche and Ca could succeed in establishing the fact that the heating power of coal is due solely or even principally to its relative amount of carbon, it follows that "Welsh coal must rise in the market, for the greater part of the coal from that district is of the anthracite kind, none of which is worked in the north of England. To prove the absurdity, how- ever, of the above attempt, I will quote two or three cases from Table No. 6. : — Theoretical Name of the Coal. Weight of Water Excess Evaporated due to Volatile Coke. by Coal. Ingredients. "Welsh — Graigola - - - - 11-301 13-563 2-262 1 4-335 5-01 Z Old Castle Fiery Vein - Mynydd Newydd - Scotch — 10-601 9-831 14-936 14-904 The thing speaks Dalkeith Jewel Seam 6-239 12-313 6-074 for itself English — Broomhill 1-111 14-863 '7-162J After theoretically demonstrating that " the evaporative value of a bituminous coal is expressed by the evaporative value of its coke, the heat of combustion of its volatile products provmg in practice little more than that necessary to volatilize them," we are suddenly greeted with the following paragraph : — " The whole system of manufacturing coke is at present very imperfect Besides losing the volatile combustible substances, which, under new adjustments, might be made of much value, an immense quantity of ammonia is lost by being thrown into the atmosphere. Ammonia and its salts are daily becoming more valuable to agriculture, and it is their comparative high price alone which prevents their universal use to all kinds of cereal cultivations. By a construction of the most simple kind the coke- ovens now in use might be made to economize much of the nitrogen, which invariably escapes in the form of ammonia. As an inducement to this economy, we have ap> 3L2 k ' "^' h)! k i' 444 COAL. pended to Table 6. two columns showing the quantity of ammonia and its corre» ponding quantity of commercial sulphate which each 100 lbs. of the respective coals may be made to produce. When it is remembered that the price of sulphate of ammonia is about 13/. per ton, or that 100 tons (of coal, we suppose) in coking is (are ?) capable of producing on an average about six tons of this salt^ its neglect is highly reprehensible." Nothing has tended half so much to retard the cultivation of chemistiy by our practical manufacturers as the kind of statements of which the above is a sample. Written by individuals wholly ignorant of the subject of which they treat, these assertions serve only to amuse practical men, and to demonstrate the stupendous folly and assurance of their authors. Imperfection is an attribute of humanity, but that the present system of making coke is very imperfect remains to be proved. The Tolatile combustible matter of the coal is not lost; on the contrary, it i« employed as a means of converting the cinder of the coal into coke, and that, too, by the heat which it evolves in burning ; and if that heat was so inconsiderable as the report would lead us to suppose, mere cinder alone would remain in the coke-oven, even after the heat had been kept up for ninety-six hours. Perhaps the framers of the report may want to know the distinction between cinders and coke. Coke, if good, sinks in water; bad coke or cinder swims. The reason of this is very simple. The longer and higher the heat to which carbon from wood or coal is exposed the more it contracts, and consequently the denser it becomes. The volatile combustible matter of the coal is employed, then, in producing the requisite temperature for coking, and the oven is so contrived as to retain the heat a sufficient time to produce the necessary aggregation of the particles of carbon, or, in plain words, the condensation of the coke: to assert that this volatile combustible matter is lost is perfectly ridiculous. We are next informed that "an immense quantity of ammonia is lost by 1)eing thrown into the atmosphere," and that by " a construction of the most simple kind this loss might be avoided." Lord Dundonald, about fifty years ago, had the same idea, and tried it on a large scale ; it is unnecessary to say that it proved to be a complete failure, although sulphate of ammonia was then worth four or five times its present price. But uie most absurd part of this scientific soap-bubble is contained in the last sentence : — " 100 tons in coking is capable of producing on an average about six tons of this salt" (sulphate of ammonia). Now, let us for a few minutes imagine my Lord Grey desirous as (we have no doubt he is) of making the most of his Broomhill coal. Passing his eye down column 1. of Table 6., he sees at a glance that 100 tons of coal will produce 8'674 tons of sulphate of ammonia, worth 13/. per ton. Making a little allowance for loss, he says to himself " Well, call it 8^ tons ; and now how much sulphuric acid is required T' We will suppose him practically acquainted with Dr. Wollaston's scale, and that, valuing common " chamber acid at uiree farthings per cent, he has arrived at the following conclusion :—> 100 tons of coal, at 3«. Ad. per ton 6i tons of sulphuric acid, as above will produce 8i tons of sulphate of ammonia, worth 110 10 and 70 tons of coke, at 8«. 6d per ton /. ». d. 16 13 4 45 10 62 3 4 /. «. d. 110 10 29 15 ^~i 140 5 A promising speculation truly, if his lordship could only economize " the nitrogen which invariably escapes in the form of ammonia." But, most unfortunately, the ni- trogen does not " invariably escape in the form of ammonia," for in practice nine-tenths of it invariably escape in the form of nitrogen, as any experienced gas manufacturer can testify, and as the experiments quoted in the report abundantly prove, for accord- ing to Mr. F. C. Wrightson (a pupil of Liebig), who {vide Report, page 6.) had fitted ** mmself by special study for an undertaking requiring so much delicacy of manipula- tion," — according, then, to Mr. Wrightson (page 68.^ the Binea coal and the Llangen* neck coal gave by actual experiment in 100 parts 0'08 of ammonia, or '310 of sulphate of ammonia. Now, if we compare this with Table 6. we shall find — Binea coal ) might, could, would, or j 6*741 ) really did j 0-310 Llangenneck ) should produce ( 5*044 ) produce ( 0*310 or about ^th of the quantity theoretically obtained by Sir H. De la Beche and Dr. Lyon COAL. 445 riayfair; yet these are the individuals who find fault with our manufacturers, and pretend to improve our processes. With quite as much practical utility rnight these gentlemen have detailed to us the quantity of pure diamond which the coals in question would produce, if we knew how ; as the amount of ammonia which they might give off if they would. Of the analytical part of the report we will say little naore than that it is in perfect keeping with the rest In the first place, chloride of calcium is employed to remove water and ammonia from the gas, although a very little practical knowledge of gas purification would have taught the operator that, when water and ammonia are absorbed by chloride of calcium, carbonic acid is also taken up, so as to produce car- bonate of lime and muriate of ammonia ; and as this carbonic acid must have been regarded either as ammonia or water, it follows that the experimental results are value- less. The substance which ought to have been employed to absorb water and ammonia under the circumstances is the fused or glacial phosphoric acid ; but what real value can we attach to experiments made upon less than half a grain of coal, in which the errors^ and errors there are, have been multiplied at least 300,000 times ? For example, at page 58., we find " Anthracite, from T. Aubrey and Co." The quantity of this coal taken for analysis was 0*2763 of a grain, or rather more than i of a grain. Now, sup- posing it had even equalled J of a grain, then to bring this to a pound it must be multi- plied 21,000 times, and to raise this last to the weight of water which 1 lb. of such coal could theoretically evaporate, as represented at column 4. of Table 6., this 21,000 must he multiplied by 14*593 ; therefore, if any error occurred in the analysis of this an- thracite coal, it has been multiplied upwards of 306,453 times; in regard to the quantity of water which 1 lb. of such coal can evaporate, as exhibited in column 4. of Table 6. The idea^ however, of weighing the joJoo^^h of a grain is perfectly new to us^ who have always regarded even the lioth as something too nearly approaching the im- ponderable. These remarks apply equally to the experiments with litharge; no allow- ance is made, or notice taken of the error arising from the presence of iron pyrites in the coal, although this substance would reduce more than 9 times its weight of litharge^ and the error thus produced has been multiplied upwards of 90,000 times in column 6. of Table 4. ; and in the case of the anthracite coal above mentioned this error has been increased 104,507 times. Nor is the quantity of iron pyrites inconsiderable in many of these coals, for, according to Table 3., the following contain a portion of sulphur equivalent to bisulphuret of iron, as under: — Slievardagh - - - - 12*67 per cwt Resolven ... - 9*50 „ Bed was - - - - 6*56 „ Cwm Nanty Gros - - - 5*64 „ _ To pretend to attach any value to such experiments, or to the conclusions drawn from them, is a mere fallacy, and, as the whole of the theoretical part is based upon these analyses, with them it must fall to the ground as erroneous and illusory. Under these circumstances it becomes necessary to inquire most carefully into the la'-ge and practical essays made for the purpose of determining the q^uantity of water evaporated during many successive hours by considerable quantities of each particular coaL With a few exceptions, each coal was burnt for eight hours, and the experiment repeated three times, the quantity of coal consumed and of water evaporated being noted in each instance, and an average drawn from the three results obtained by each coal. If carefully conducted, this method ought to have furnished some valuable information, but the discrepancies in respect to the three results obtained from some of the coals are so enormous and unaccountable as to render the whole table suspicious^ doubtful, and therefore valueless ; indeed, the differences observable between many of the dif- ferent samples of coal are much less than the experimental differences given by one and the same coal, and which occasionally amount to little short of twenty per cent, as the following table will show [see p. 446.]. The idea of forming a table from experiments producing such discordant results is altogether preposterous, yet turn in what direction we may, the same evidence of blundering and incapacity presents itself. In the first place, the selection of the coals was bad and unfair in the extreme, and no way calculated to answer the practical end in view ; secondly, the proximate analyses are worthless, from the employment of chloride of calcium for a purpose for which it was not adapted ; thirdly, the ultimate analyses are made in quantities too small to entitle them to any confidence when their results are raised to practical purposes ; fourthly, the litharge experiments are erro- neous ; and fifthly, the practical essays by means of the Admiralty boiler are so com- pletely at vaiiance amongst themselves as to defy all arrangement or computation. The entire report is, in fact, a disgrace to the age and country we live in, and carries with it all the internal evidence of a job. . • -^ j • ^ As it is possible, however, that the Admiralty may really be serious m its desire to ascertain the true value of steam-coal, we will venture to throw out a few hmts, in order of iron pyrites for which no allowance has been 'made in the litharge ex- periments. 446 COBALT. NameofCoaL Extreme Difference in Three Trials as to the Amuunt of Water eYaporated by each respective Coal. Dutfryn - - - - - Old Castle - - - . Ward's Binea - - - - - Llangenneck - - - - Mynydd - - - - Three Quarter - - . Graigola - - - . Lydney - - - - - Pontrepoth . - - - Cwm Frood - - - - Anthracite - - - . Cwm Nanty Gros - - - Grangemouth - - - - Broomhill - - . . Resolven - - . . Pontypool - - - . Bedwas - - - - - Forth Ma wr - - - - EbbwVale - - - Fordel Splint - - - - Coleshiil Wallsend Elgin - - . 2-3 per cent 11- „ e-8 „ 14-7 . 16- „ 4-9 „ 1-4 n 21 „ 11-8 „ »1 n 1-3 „ 6-6 „ 4-8 « 6^ ,. 6-2 „ 18-9 „ 13-4 „ 9-6 » 16-7 „ H-5 .. 11-6 „ 7-3 „ that that august body of well-paid functionaries may look before they leap into a subject 80 intimately connected with our national interests. In working a seam of coal, experience has shown that the quality of the coal is not uniform, and that a coal may be improving or deteriorating as the workings are carried on, in one or another direction. From this it follows that any particular coal examined, say in 1846, is by no means to be regarded as possessing the same value in 1848, since this may have changed considerably, if the working of the coal has been carried on to any great extent ; and it is the determination of this very fact which constitutes the real source of utility to be derived from a Government investigation. The proximate value of a coal is soon determined by actual experiment, from the amount of work done, and a market value is given in accordance with these rough results ; but, when once that value has become fixed, there it remains for many years, whether the coal continues uniform or not, and it is only slowly and by degrees that the change becomes apparent, An establishment for determining matters of this kind is, therefore, much needed, but, to be useful, it must obviously be permanent Again, as the transmission of heat from one body to another is proportional to the diflference of temperature between the bodies themselves, it is clear that the water operated on should have one uniform temperature in all the experiments, and there are many reasons why this should be the boiling point. Tlie quantity of water evaporated should not be inferred from the quantity which has escaped from a boiler during an experiment ; independent of the possibility of leakage, much water is occasionally carried off mechanically by the steam ; hence the origin of "priming*' The most unobjectionable method would be to distil the water and after- wards measure it, the still-head being provided with a return-pipe, as is usual, for the fluid mechanically projected. The ordinary modes of favouring the transmission of heat from the furnace to the boiler, and of preventing its escape in any other direction than into the refrigeratory, should be had recourse to. A chemist is of no use for such inves- tigations ; if any chemical question should arise out of the experiments, it would be better to consult some one of established reputation. The stoker should be intelligent, and practically acquainted with the different modes of fire necessary for anthracitic, open-burning, and bituminous, or caking coal ; for whilst the first of these will take, nay requires, eighteen or twenty inches of fuel on the bars, the last will not bear more than four or six, without an enormous loss of heating-power. To this cause must be ascribed much of the discrepancy apparent in the experimental results obtained by the Admiralty boiler. — Mr. Lerois Thompson, in " T?ie Chemical Time»" for December, 1 848. COBALT. This metal being difficult to reduce from its ores, is therefore very little known, and has not hitherto been employed in its simple state in any of the arts ; but its oxide has been extensively used on account of the rich blue colour which it imparts to glass, and the glazes of porcelain and stone-ware. The principal ores of cobalt are COBALT 447 those designated by mineralogists under the names of arsenical cobalt and gray cobalt. The first contains, in addition to cobalt, some arsenic, iron, nickel, and occasionally sil« ver, &c. The other is a compound of cobalt with iron, arsenic, sulphur, and nickel. Among the gray cobalts, the ore most esteemed for its purity is that of T^.»aberg in Sweden. It is often in regular crystals, which possess the lustre and color of polished steel. The specific gravity of cobalt pyrites is 6-36 to 4*66. The Tunaberg variety afibrded to Klaproth, cobalt, 44 ; arsenic, 55-5 ; sulphur, 0-5 ; so that it is an arseni- uret. Others, however, contain much sulphur as well as iron. It imparts at the blowpipe a blue color to borax and other fluxes, and gives out arsenical fumes. The ore being picked, to separate its concomitant stony matter, is pounded fine and passed through a sieve ; and is also occasionally washed. The powder is then spread on the sole of a reverberalory furnace, the flue of which leads into a long hori- zontal chimney. Here it is exposed to calcination for several hours, to expel the sul- phur and arsenic that may be present ; the former burning away in sulphurous acid gas, the latter being condensed into the white oxyde or arsenious acid, whence chiefly the market is supplied with this article. This calcining process can never disengage the whole of these volatile ingredients, and there is therefore a point beyond which it is useless to push it ; but the small quantities that remain are not injurious to the subse- quent operations. The roasted ore is sifted anew ; reduced to a very fine powder, and then mixed with 2 or 3 parts of very pure silicious sand, i8 be converted into what is called zaffre. With this product glasses are generally colored blue, as well as enam- els and pottery glaze. In the works where cobalt ores are treated, a blue glass is pre- pared with the zaffre, which is well known under the name of smalt or azure blue. This azure is made by adding to the zaflTre 2 or 3 parts of potash, according to its rich- ness in cobalt, and melting the mixture in earthen crucibles. The fused mass is thrown out while hot into water ; and is afterwards triturated and levigated in mills mounted for the purpose. There remains at the bottom of the earthen pot a metallic lump, which contains a little cobalt, much nickel, arsenic, iron, &c. This is called speiss. As'it is the oxyde of cobalt which has the coloring quality, the calcination serves the purpose of oxydizement, as well as of expelling the foreign matters. A finer cobalt oxyde is procured for painting upon hard porcelain, by boiling the cobalt ore in nitric acid, which converts the arsenic into an acid, and combines it with the dif- ferent metals present in the mineral. These arseniates, being unequally soluble in nitric acid, may be separated in succession by a cautious addition of carbonate of soda or pot- ash ; and the arseniate of cobalt as the most soluble remains unaffected. It has a rose color, and is easil.' distinguishable, whence the precipitation may be stopped at the proper point. The above solution should be much diluted, and the alkali should be cautiously added, with frequent agitation. The cobalt ores, rich in nickel, are exposed to slow oxydizement in the air, whereby the iron, cobalt, arsenic, and sulphur get oxygenated by the atmospheric moisture, but the nickel continues in the metallic state. This action of the weather must not be extended beyond a year, otherwise the nickel becomes affected, and injures the cobalt blue. The ore hereby increases in weight, from 8 to 10 per cent. Fig. 362 is a longitudinal section of the furnace : fig. 363, a horizontal section upon a level with the Bole of the hearth. It is constructed for wood fuel, and the hearth is composed of fire-bricks or tile?. The vapors and gases disengaged in the roasting pass off through the flues a o, into the channels 6 b, and thence by c into the common vent, or poison chamber. See the representation of the poison ♦ower of Altenberg, under the article ARSENia The flues are cleared out by means of openings left at suitable situa- tions in the brick- work of the chimneys. The azure manufacture is carried on chiefly in winter, in order that 862 E^^^^^^^^^^P^^*^^^^^^^ the external cold may favour the more complete condensation of the acids of arsenic. From 3 to 5 cwt =* of Schlich (pasty ore) are roasted at '***" one operation, and its bed is laid from 6 to 6 inches thick. After two hours, it must be turned over; and the stirring must be repeated every half hour, till no more arsenic is ob- served to exhale. The process being then finished, the ore must be raked out of the furnace, and another charge introduced. 1 II 448 COBALT. i 363 |. ^^...A.>yy>/>>/W /'Vx^//>xy/.;d^^M>/^/^^^ 864 865 The duration of the roasting it regulated partly by the proportion of sulphur and arsenic present, and partly by the amount of nickel; which must not be suffered to be- come oxydized, lest it should spoil the color of the smalt. The latter ores should be but slightly roasted, so as to convert the nickel into speiss. The roasted ore must be sifted in a safety apparatus. The loss of weight in the roasting amounts, upon the average, to 36 per cent. The roasted ore has a brownish gray hue, and is called safflor in German, and is dis- tributed into different sorts. F F S is the finest safre ; F S, fine ; OS, ordinary ; and M S, middling. These varieties proceed from various mix- tures of the calcined ores. The roasted ore is ground up along with sand, elatriated, and, when dry, if called zaffre. It is then mixed with a suflicient quantity of potash foi converting the mixture into a glass. Figs. 364 and 365, represent a round smalt furnace, in two vertical sections, at right angles to each other. The fire-place is vaulted or arched ; the flame orifice a, is in the middle of the furnace ; 6 is the feed hole ; c, a tunnel which serves as an ash-pit, and to supply air ; d, open- ings through which the air arrives at the fuel, the wood being placed upon the vault; e, knee holes for tsiking out the scorise from the pot bottoms; /, working orifices, with cast-iron plates g, in front of them. Under these are the additional out- lets h. The smoke and flame pass off through the orifices t, which ter- minate in expanded flues, where the sand may be calcined or the wood may be baked. Eight hours are sufficient for one vitrifying operation, during which the glass is stirred about several times in the earthen melting pots. ^ , The preparation of the different shades of blue glass is considered a secret in th« smelting works ; and marked with the following letters : — F F F C, the finest ; F C| fine; M C, middling; O C, ordinary, A melting furnace, containing 8 pots of glass, produces in 24 hours, from 24 cwts. of the mixture, 19 cwts. of blue glass; and from ^ to I cwt of scorise or speiss (speise). The composition xpeise, according to Berthier, is,— nickel, 490; arsenic, 37-8; sulphur, 7-8; copper, 1-6; cobalt, 3-2 in 100. Nickel, arsenic, and sulphur, are its essential constituents ; the rest are accidental, and often absent The freer the cobalt ore is from foreign metals, the finer is the colour, and the deeper is the shade ; paler tints are easily obtained by dilution with more glass. The presence of nickel gives a violet tone. The production of smalt in the Prussian states amounted, in 1830, to 7452^ cwts.; and in Saxony to 9697 cwts. ; in 1825, to 12,310 cwts. One process for making fine smalt has been given under the title Azuke ; I shall in- troduce another somewhat different here. The ore of cobalt is to be reduced to very fine powder, and then roasted with much care. One part, by weight, is next to be introduced, in successive small portions, into an iron vessel, in which three parts of acid sulphate of potassa has been previously fused, at a moderate temperature. The mixture, at first fluid, soon becomes thick and firm, when the fire is to be increased, until the mass is in perfect fusion, and all white vapours have ceased It is then to be taken out of the crucible with an iron J. COCHINEAL. 449 ladle, the crucible is to be recharged with acid sulphate of potash, and the operation continued as before, until the vessel is useless. The fused mass contains sulphate of cobalt, neutral sulphate of potassa, and arseniale of iron, with a little cobalt. It is to be pulverized, and boiled in an iron vessel, with water, as long as the powder continues rough to the touch. The white, or yellowish white residue, may be allowed to separate from the solution, either by deposition or filtration. Carbonate of potassa, free from siliea, is then to be added to the solution, and the carbonate of cobali thrown down is to be separated and well washed, if possible, with warm water ; the same water may be used to wash other portions of the fused mass. The filtered liquid which first passes is a saturated solution of sulphate of potassa : being evaporated to dryness in an iron res- sel, it may be reconverted into acid sulphate by fusing it with one half its weight of sulphuric acid : this salt is then as useful as at first. The oxyde of cobalt thus obtained contains no nickel ; so little oxyde of iron is pre- sent, that infusion of galls does not show its presence ; it may contain a little copper, if that metal exists in the ore, but it is easily separated by the known methods. Sometimes sulphureted hydrogen will produce a yellow brown precipitate in the solution of the fused mass ; this, however, contains no arsenic, but is either sulphuret of antimony or bismuth, or a mixture of bath. It has been found advantageous to add to the fused mass sulphate of iron, calcined to redness, and one tenth of nitre when the residue is arseniate of iron, and contains no arseniate of cobalt. There is then no occasion to act upon the residue a second time for the cobalt in it. This process is founded on the circumstances that the sulphate of cobalt is not de- composed by a red heat, and that the arseniates of iron and cobalt are insoluble in all neutral liquids. It is quite evident, that, to obtain a perfect result, the excess of acid in the bisulphate of potassa must be completely driven off by the red heat applied. 110,646 lbs. of smalts were imported into the United Kingdom in 1835, and 96,949 were retained for home consumptin. In 1834, only 16,223 lbs. were retained. In 1835, 322,562 lbs. of zaffres were imported, and 336,824 are stated to have been retained, which is obviously an error, 284,000 lbs. were retained in 1834. COCCULUS INDICUS, or Indian berry, is the fruit of the Menispermum Coccultu, a large tree, which grows upon the coasts of Malabar, Ceylon, &c. The fruit is blackish, and of the size of a large pea. It owes its narcotic and poisonous qualities to the vegeto-alk aline chemical principle called picrotoxiay of which it contains about one fiftieth part of its weight. It is sometimes thrown into waters to intoxicate or kill fishes; and it is said to have been employed to increase the inebriating qualities of ale or beer. Its use for this purpose is prohibited by act of parliament, under a penalty of 200/. upon fche brewer, and 500/. upon the seller of the drug. COCHINEAL was taken in Europe at first for a seed, but was proved by the obser- rations of Lewenhoeck to be an insect, being the female of that species of shield-lonse^ or coccusy discovered in Mexico, so long ago as 1518. It is brought to us from Mexico^ where the animal lives upon the cactus opuniia or nopal. Two sorts of cochineal are gathered — the wild, from the woods, called by the Spanish name grana silvestra ; and the cultivated, or the grana fina, termed also meaUque^ from the name, of a Mexican province. The first is smaller, and covered with a cottony down, which increases its bulk with a matter useless in dyeing ; it yields, therefore, in equal weight, much less color, and is of inferior price to that of the fine cochineal. But these disadvantages are compensated in some measure to the growers by its being reared more easily, and less expensively ; partly by the effect of its down, which enables it better to resist raine and storms. • The wild cochineal, when it is bred upon the field nopal, loses in part the tenacity and quantity of its cotton, and acquires a size double of what it has on the wild opuntias. It may therefore be hoped, that it will be improved by persevering care in the rearing of it, when it will approach more and more to fine cochineaL The fine cochineal, when well dried and well preserved, should have a gray colour, bordering on purple. The gray is owing to the powder, which naturally covers it, and of which a little adheres ; so also to a waxy fat. The purple shade arises from the colour extracted by the water in which they were killed. It is wrinkled with parallel furrows across its back, which are intersected in the middle by a longitudinal one; hence, when viewed by a magnifier, or even a sharp naked eye, especially after being swollen by soaking for a little in water, it is easily distinguished from the factitious, smooth, glistening, black grains, of no value, called East India cochineal, with which it is often shamefully adulterated by certain London merchants. The genuine cochineal has the shape of an egg, bisected through its long axis, or of a tortoise, being rounded like a shield upon the back, flat upon the belly, and without wings. These female insects are gathered off the leaves of the nopal plant, after it has ripened 450 COCfflNEAL. COCHINEAL. 451 1 1 Z5 » its fruit, a few only being left for brood, and are killed, either by a momentary immer- sion in boiling water, by drying upon heated plates, or in ovens; the ^^^.^^^^"^-^j;.^" ash-gray color, constituting the silver cochineal, or jaspeada; the second are Wack^h, call^ Zgra, and are most esteemed, being probably driest ; the first are reddish brown aXeckoned inferior to the other two. The dry cochineal being sifted, the dust, with the imperfect insects and fragments which pass through, are sold under the name of ^C^dihineal keeps for a long time in a dry place. Hellot says that he has tried some 130 years old, which produced the same effect as new cochineal. r v We are indebted to MM. Pelletier and Caventou for a chemical investigation of cochi- neal, in which its coloring matter was skilfully eliminated. Purified sulphuric ether acquired by digestion with it a golden yellow color, amounting by Dr. John to one tenth of the weight of the insect. This infusion left, on evaporation, a fatty wax of the same color. oa • r • «- Cochineal, exhausted by ether, was treated with alcohol at AQP B. After 30 infusions in the di^^ester of M. Chevreul, the cochineal continued to retam color, although tne alcohol had ceased to have any effect on it. The first alcoholic liquors were of a red verging on yellow. On cooling, they let fall a granular matter. By spontaneous evapo- ration, this matter, oC a fine red color, separated, assuming more of the crystalline ap- pearance. These species of crystals dissolved entirely in water, which they tmged ol « ^^Thls^ matter has a very brilliant purple-red color; it adheres strongly to the sides of the vessels ; it has a granular and somewhat ciystalline aspect, very different, however, from those compound crystals alluded to above ; it is not altered by the air, nor does it sensibly attract moisture. Exposed to the action of heat, it melts at about the fiftieth degree centigrade (122? Fahr.). At a higher temperature it swells up, and is decoin- posed with the production of carbureted hydrogen, much oil, and a small quantity ol water, very slightly acidulous. No trace of ammonia was found m these products. The coloring principle of cochineal is very soluble in water. By evaporation, the Uquid assumes the appearance of sirup, but never yields crystals. .I'^/^qmres of this matter a portion almost imponderable to give a perceptible tinge of bright purplish red to a large body of water. Alcohol dissolves this coloring substance, but, as we have al- ready stated, the more highly it is rectified the less of it does it dissolve. Sulphuric ether does not dL^solve the coloring principle of cochineal; but weak acids do, possibly owing to their water of dUution. No acid precipitates it in its pure state. This coloring prin- ciple, however, appears to be precipitable by all the acids, when it is accompanied by the animal matter of the cochineal. . The affinity of alumina for the coloring matter is very remarkable. When that eartft, newly precipitated, is put into a watery solution of the coloring principle, this is imme- diately seized by the alumina. The water becomes coloriess, and a fine red lake is ob- tained, if we operate at the temperature of the atmosphere ; but if the liquor has beei hot, the color passes to crimson, and the shade becomes more and more violet, accord ing to the elevation of the temperature, and the continuance of the ebuUition. The salts of tin exercise upon the coloring matter of cochineal a remarkable action. The muriatic protoxyde of tin forms a very abundant violet precipitate in the liquid This precipitate verges on crimson, if the salt contains an excess of acid. Jhe munaUe deutoxyde of tin produces no precipitate, but changes the color to scarlet-red. If gelati- nous alumina be now added, we obtain a fine red precipitate, which does not pass to "'To^'thi^co Wng principle the name carminium bas been given, because it forms the basis of the pigment called carmine. , . , . , • i. • The process followed in Germany for making carmine, which consists in pouring a certain quantity of solution of alum into a decoction of cochineal, is the most simple of all and affords^in explanation of the formation of carmine, which is merely the car- m^nfum and the animal matter precipitated by the excess of acid m the salt, which has teken down with it a small quantity of alumina ; though it appears that alumina ought not to be regarded as essential to the formation of carmine. In fact, by another proceaa ^lled bv the name of Madame Cenette of Amsterdam, the carmine is thrown down by Souring into the decoction of cochineal a certain ouantity of the bmoxalate of potash, ^hen carbonate of soda is added, then carminateJ lake also falls down. That carmine is a triple compound of animal matter, carminium, and an acid, appears from the cir- cumstance that liquors which have afforded their carmine, when a somewhat strong ac.Tis poured into them, yield a new formation of carmine by the precipitation of the Z porCns of the animaf matter. But whenever the whole animal matter is thrown Swrthe decoctions, although still much charged with the colourmg prmciple, can Xrd no more canine. sSch decoctions may be usefully employed to make car- minated lakeZ saturating the acid with a slight excess of alkali, and adding gelatmous S^l The precipitates obtained, on aiding acid to the alkaline decocUons of earmines, since they do not contain alumina; but the small quantity of alumina which is thrown down by alum in the manufacture of carmine, augments its bulk and x^ight It gives, besides, a greater lustre to the color, even though diluting and weakening it a little. The carmines found in the shops of Paris were analyzed, and yielded the same pro- ducts. They are decomposed by the action of heat, with the diffusion at first of a very strong smell of burning animal matter, and then of sulphur. A white powder remained, amounting to about one tenth of the matter employed, and which was found to be alu- mina. Other quantities of carmine were treated with a solution of caustic potash, which completely dissolved them, with the exception of a beautiful red powder, not acted on by potash and concentrated acids, and which was recognised to be red sulphuret of mercurj or vermilion. This matter, evidently foreign to the carmine, appears to have been ad- ded in order to increase its weight. The preceding observations and experiments seem calculated to throw some light on the art of dyeing scarlet and crimson. The former is effected by employing a cochineal bath, to which there have been added, in determinate proportions, acidulous tartrate of potash, and nitro-muriatic deutoxyde of tin. The effect of these two salts is now well known. The former, in consequence of its excess of acid, tends to redden the color, and to precipitate it along with the animal matter ; the latter acts in the same manner, at first by its excess of acid, then by the oxyde of tin which falls down also with the carmine and animal matter, and is fixed on the wool, with which it has of itself a strong tendency to combine. MM. Pelletier and Caventou remark, that " to abtain a beautiful shade, the muriate of tin ought to be entirely at the maximum of oxydizement ; and it is in reality in this state that it must exist in the solution of tin prepared according to the proportions prescribed in M. Berthollet*s treatise on dyeing." We hence see why, in dyeing scarlet, the employment of alum is carefully avoided, as this salt tends to convert the shade to a crimson. The presence of an alkali would seem less to be fieared. The alkali would occasion, no doubt, a crimson-colored bath ; but it would be easy in this case to restore the color, by using a large quantity of tartar. We shoukl, therefore, procure the advantage of having a bath better charged with coloring matter and animal substance. It is for experience on the large scale to determine this point. As to the earthy salts, they must be carefully avoided ; and if the waters be se- lenitish, it would be a reason foi adding a Jttle alkali. To obtain crimson, it is sufficient, as we know, to add alum to the cochineal bath, or to boil the scarlet cloth in alum water. It is also proper to diminish the dose of the salt of tin, since it is found to counteract the action of the alum. The alkalis ought to be rejected as a means of changing scarlet to crimson. In fact, crimsons by this process cannot be permanent colors, as they pass into reds by the actios of acids. According to M. Von Grotthuss, carmine may be deprived of its golden shade bj ammonia, and subsequent treatment with acetic acid and alcohol. Since this fact was made known, M. Herschel, color maker at Halle, has prepared a most beautiful carmine. The officers of Her Majesty's Customs have lately detected a system of adulterating cochineal, which has been practised for many years upon a prodigious scale by a mercan- tile house in London. I have analyzed about 100 samples of such cochineal, from which It appears that the genuine article is moistened with gum-water, agitated in a box of leather bag, first, with sulphate of baryta in fine powder, afterward with bone of ivory black, to give it the appearance of negra cochineal, and then dried. By this means about 12 per cent of worthless heavy spar is sold at the price of cochineal, to the enrichment of the sophisticators, and the disgrace and injury of Biitish trade and manufactures. The specific gravity of genuine cochineal is r25; that of the cochineal loaded with the barytic sulphate, r35. This was taken in oil of turpentine and reduced to water as unity, because the waxy fat of the insects prevents the intimate contact of the latter liquid with them, and the ready expulsion of air from their wrinkled surface. They are not at all acted upon by the oil, but are rapidly altered by water, especially when they have been gummed and barytitied. December, 1851 • 18.50 - - 12 MonlhB, 18.51 - - 1850 - - 1849 - - 1848 • - • I.«a«ie(i. 1,203 bags 1,6!>5 — 16,561 — 17,765 — 12.604 — 13.521 — Delivered. 692 bags 595 — 16.180 — 13,096 — 13,594 — 11,506 — Stock, l8t of January. — bags 9.G01 8.620 3,951 4.933 Humboldt states that so long ago as the year 1736, there was imported into Europe from South America cochineal to the value of 15 millions of francs. Its high price had for a long time induced dyers to look out for cheaper substitutes in dyeing red, and lince science has introduced so many improvements in tinctorial processes, both madder and lac have been made to supersede cochineal to a very great extent Its pnce has, in 452 COFFEE. COFFEE. 453 r) V- ' consequence of this substitntion, as well as from more saccessfal modes of cultivation, fallen very greatly of late years. In January, 1852, the prices of Honduras cochineal ranged from 2?. 9cL to 5«. per lb., and Mexican from 2s. 7a. to 3«. 4J. per lb. COCOA, STEARINE, and ELAINE. Mr. Soames obtained a patent in September, 1829, for making these useful articles, by the following process : — He takes the substance called cocoa-nut oil, in the state of lard, in which it is imported into this country, and submits it to a strong hydraulic pressure, having made it up in smaB packages, 3 or 4 inches wide, 2 feet long, and 1 or 1^ inches thick. These packages art formed by first wrapping up the said substance in a strong linen cloth, of close texture^ and then in an outward wrapper of strong sail cloth. The packages are to be placed sidf by side, in single rows., between the plates of the press, allowing a smaH space betweei the packages for the escape of the elaine. The temperature at which the pressure is begun, should be from about 50 to 55 degrees, or in summer as nearly at this pitch as can be obtained, and the packages of the said substance intended for pressure, should be exposed for several hours previously to about the same temperature. When the packages will no longer yield their oil or elaine freely at this temperature, it is to be gradually raised ; but it must at no time exceed 65 degrees, and the lower the temperature at which the separation can be effected, the better will be the quality of the oil expressed. When the packages are sufficiently pressed, that is, when they will give out no more oil, or yield it only in drops at long intervals, the residuum in them is to be taken out and cleansed and purified, which is done by melting it in a well-tinned copper vessel, which is fixed in an outer vessel, having a rdcant space between, closed at the top, into which steam is admitted, and the heat is kept up moderately for a sufficient time to allow the impurities to subside ; but if a still higher degree of purity is required, it is necessary to pass it through filters of thick flannel lined with blotting paper. Having been thus cleansed or purified, it is fit for the manufacture of candles, which are made by the ordinary process used in making mould tallow candles. Having thus disposed of the stearine, or what is called the first product, he proceeds with the elaine or oil expressed from it, and which he calls the second product, as follows : that is to say, he purifies it by an admixture, according to the degree of its apparent foulness, of from 1 to 2 per cent, by weight of the sulphuric acid of commerce, of about 1*80 specific gravity, diluted with six times its weight of water. The whole is then to be violently agitated by mechanical means, and he prefers for this purpose the use of a vessel con- structed on the principle of a common barrel churn. When sufficiently agitated, it will have a dirty whitish appearance, and is then to be d awn off into another vessel, in which it is to be allowed to settle, and any scum that rises is to be carefully taken off. In a day or two the impurities will be deposited at the bottom of the oil, which will then be- eome clear, or nearly so, and it is to be filtered through a thick woollen doth^ aAer which it will be fit for burning in ordinary lamps and for other uses. The process of separating the elaine from the stearine, by pressure, in manner afore- said, had never before beenv applied to the substance called cocoa-nut oil, and consequently no product had heretofore '^een obtained thereby from that substance, fit for being ma- nufactured into candles in the ordinary way, or for ^eing refined by any of the nsni? modes, so as to burn in ordinary lamps, both which objects are obtained by this method of preparing or manufacturing the said substance. Candles well made from the above material are a very superior article. The light produced is more brilliant than from the same sized candle made of tallow ; the flame is perfectly colorless, and the wick remains free from cinder, or any degree of foulness du- ring combustion. COFFEE. The coffee is the seed of a tree of the family rubiacea, and belongs to the Pentandria monogynia of Linnaeus. There are several species of the genus, but the only one cultivated is the Coffcea Arahica^ a native of Upper Ethiopia and Arabia Felix. It rises to the height of 15 or 20 feet ; its trunk sends forth opposite branches in pairs above and at right angles to each other ; the leaves resemble those of the common laurel, al- though not so dry and thick. From the angle of the leaf-stalks small groups of white flowers issue, which are like those of the Spanish jasmine. These flowers fade very soon, and are replaced by a kind of fruit not unlike a cherry, which contains a yellow glairy fluid, enveloping two small seeds or berries convex upon one side, flat and furrowed upon the other in the direction of the long axis. These seeds are of a homy or cartilaginous nature ; they are glued together, each being surrounded with a peculiar coriaceous mem- brane. They constitute the coffee of commerce. It was not till towards the end of the 15th century that the coffee-tree began to be cul- tivated in Arabia. Historians usually ascribe the discovery of the use of coffee as a be* verage to the superior of a monastry there, who, desirous of preventing the monks from sleeping at their nocturnal services, made them drink ihe infusion of coffee upon the re- port of shepherds, who pretended that their flocks were more lively after browsing on the fruit of that *)lant. The use of coffee was soon rapidly spread, but it encountered much opposition on thft part of the Turkish government, and became the occasion of public assemblies. Under the reign of Amurath Til. the mufti procured a law to shut all the cof- fee-houses, and this act of suppression was renewed under the minority of Mahomet IV, It was not till 1554, under Solyman the Great, that the drinking of coffee was accredited in Constantinople ; and a century elapsed before it was known in London and Paris. Soly- man Aga introduced its use into the latter city in 1669, and in 1672 an Armenian estab- lished the first cafe at the fair of Saint Germain. When coffee became somewhat of a necessary of life, from the influence of habit among the people, all the European powers who had colonies between the tropics, pro- jected to form plantations of coffee-trees in them. The Dutch were the first who trans- ported the coffee plant from Moka to Batavia, and from Batavia to Amsterdam. In 1714 the magistrates of that city sent a root to Louis XIV., which he caused to be planted in the Jardin du Roi. This became the parent stock of all the French coffee plan- tations in Martinique. The most extensive culture of coffee is still in Arabia Felix, and principally in the kingdom of Yemen, towards the cantons of Aden and Moka. Although these countries are very hot in the plains, they possess mountains where the air is mild. The coffee is generally grown half way up on their slopes. When cultivated on the lower grounds it is always surrounded by large trees which shelter it from the torrid sun, and prevent its fruit from withering before their maturity. The harvest is gathered at three periods ; the most considerable occurs in May, when the reapers begin by spreading cloths under the trees, then shaking the branches strongly, so as to make the fruit drop, which they collect, and expose upon mats to dry. They then pass over the dried berries a very heavy roller, to break the envelops, which are afterwards winnowed away with a fan. The interior bean is again dried before being laid up in store. In Demarara, Berbice, and some of our West India islands, where much good coffee is now raised, a different mode of treating the pulpy fruit and curing the beans is adopted. When the cherry-looking berry has assumed a deep-red color it is gathered, and immediately subjected to the operations of a mill composed of two wooden rollers, furnished with iron plates, which revolve near a third fixed roller called the chopt. The berries are fed into a hopper above the rollers, and falling down between them and the chops, they are stripped of their outer skin and pulp, while the twin beans are se- parated from each other. These beans then fall upon a sieve, which allows the skin and the pulp to pass through, while the hard beans accumulate and are progressively slid over the edge into baskets. They are next steeped for a night in water, thoroughly washed in the morning, and afterwards dried in the sun. They are now ready for the peeling mill, a wooden edge wheel turned vertically by a horse yoked to the extremity of its horizontal axis. In travelling over the coffee, it bursts and detaches the coriaceous or parchment-like skin which surrounds each hemispherical bean. It is then freed from the membranes by a winnowing machine, in which four pieces of tin made fast to an axle are caused to revolve with great velocity. Com fanners would answer better than this nide instmment of negro invention. The coffee is finally spread upon mats or tablci| picked clean, and packed up for shipment. The most highly esteemed coffee is that of Moka. It Las a smaller and a roundei bean; a more agreeable taste and smell than any other. Its xtlor is yellow. Next to it in European reputation are the Martinique and Bourbon coffees ; the former is larger than the Arabian, and more oblong ; it is rounded at the ends ; its color is green- i«h, and it preserves almost always a silver gray pellicle, which comes off in the roasting. The BourbDn coffee approaches nearest to the Moka, from which it originally sprang. The Saint Domingo coffee has its two extremities pointed, and is much less esteem^ than the preceding. The coffee-tree flourishes in hilly districts, where its root can be kept dry, while its leaves are refreshed with frequent showers. Rocky ground, with rich decomposed mould in the fissures, agrees best with it. Though it would grow, as we have said, to the height of 15 or 20 feet, yet it is usually kept down by pruning to that of five feet, for increasing the production of the fruit, as well as for the convenience of crop- ping. It begins to yield fruit the third year, but is not in full bearing till the fifth, does not thrive beyond the twenty-fifth, and is useless in general at the thirtieth. In the coffee husbandry, the plants should be placed eight feet apart, as the trees throw out extensive horizontal branches, and in holes ten or twelve feet deep, to secure a con- stant supply of moisture. Coffee has been analyzed by a great many chemists, with considerable diversity of results. The best analysis perhaps is that of Schrader. He found that the raw beans distilled with water in a retort communicated to it their flavor and rendered it turbid, whence they seem to contain some volatile oil. On reboiling the beans, filtering, and evaporating the liquor to a sirup, adding a little alcohol till no more matter was preci- pitated, and then evaporating to dryness, he obtained 17*58 oer cent, of a yellowish- 454 COFFEE. COFFEE. 455 la- ^ brown transparent extract, which constitutes the characteristic part of coffee, thongh it is not in that state the pure proximate principle, called caffeine. Its most remarkable reaction is its producing, with both the protoxyde and the peroxyde salts of iron, a fine grass green color, while a dark green precipitate falls, which re-dissolves when an acid is poured into the liquor. It produces on the solution of the salts of copper scarcely any effect, till an alkali be added, when a very beautiful green color is produced, which may be employed in paintin?. Coifee beans contain also a resin, and a fatty substance somewhat like suet. According to Robiquet, ether extracts from coffee beans nearly 10 per cent, of resin and fat, but he probably exaggerates the amount. The peculiar sub- stance cafeine contained in the above extract is crystallizable. It is remarkable in regard to composition, that after urea and the uric acid, it is among organic products the richest in azote. It was discovered and described in 1820 by Runge. It does not possess alkaline properties. Pfaff obtained only 90 grains of cafeine from six pounds of coffee beans. There is also an acid in raw coffee, to which the name of ca/eic acid has been given. When distilled to dryness and decomposed^ it has the smell of roasted coffee. nru * ' f^ Coffee undergoes important changes in the process of roasting. When it is roasiea to a yellowish brown it loses, according to Cadet, 12| per cent, of its weight, and is u this state difficult to grind. When roasted to a chestnut brown it loses 18 per ceat., and when it becomes entirely black, though not at all carbonized, it has lost 23 per cent. Schrader has analyzed roasted coffee comparatively with raw coffee, and he found in the first 12| per cent, of an extract of coffee, soluble in water and alcohol, which pos- sesses nearly the properties of the extract of the raw coffee, although it has a deeper iNTown color, and softens more readily in the air. He found also 10*4 of a blackish brown gum ; 5*7 of an oxygenated extract, or rather apotheme, soluble in alcohol, inso- luble in water; 2 of a fatty substance and resin; 69 of burnt vegetable fibre, insoluble. On distilling roasted coffee with water, Schrader obtained a product which contained the aromatic principle of coffee ; it reddened litmus paper, and exhaled a strong and agree- able odor of roasted coffee. If we roast coffee in a retort, the first portions of the aro- matic principle of coffee condense into a yellow liquid in the receiver ; and these may be added to the coffee roasted in the common way, from which this matter has been expel- led and dissipated in the air. Chenevix affirmed that by the roasting of coffee a certain quantity of tannin possessing the property of precipitating gelatin is generated. Cadet made the same observation, and found, moreover, that the tannin was most abundant in the lightly roasted coffee, and that there was nearly none of it in coffee highly roasted. Paysse and Schrader, on the contrary, state that solution of gelatin does not precipitate either the decoction of roast- ed coffee or the alcoholic extract of this coffee. Runge likewise asserts that he could obtain no precipitate with gelatin ; but he says that albumen precipitates from the de- coction of roasted coffee the same kind of tannin as is precipitated from raw coffee by the acetate of lead, and set free from the lead by siiphureted hydrogen. With these resulta my own experiments agree. Gelatin certainly Ices not disturb clear infusion of roasted coffee, but the salts o^ iron blaeken it. Schrader endeavored to roast separately the different principles of coffee, but none of them exhaled the aromatic odor of roasted coffee except the horny fibrous matter. He therefore concludes that this substance contributes mainly to the characteristic taste of roasted coffee, which cannot be imitated by any other vegetable matter, and which, as we have seen, should be ascribed chiefly to the altered cafeic acid. Accordins to Garot, we may extract the cafeine without alteration from roasted coffee by precipitating its decoc- tion by subacetate of lead, treating the washed precipitate with sulphureted hydrogen, and evaporating the liquid product to dryness. Of late years, much ingenuity has been expended in contriving various forms of appa- ratus for making infusions of coffee for the table. I have tried most of them,, and find, after all, none so good as a cafetiere a la Belloyj the coffee Wggin, with the perforated tin- plate strainer, especially when the filtered liquor is kept sivnmering in a close vessel, set over a lamp or steam pan. The useful and agreeable matter in coffee is very soluble : it comes off with the first waters of infusion, and needs no boiling. To roast coffee rightly we should keep in view the proper objects of this process, which are to develop its aroma, and destroy its toughness, so that it may be readily ground to powder. Too much heat destroys those principles which we should wish to preserve, and substitutes new ones which have nothing in common with the first, but add a disagreea- ble empyreureatic taste and smell. If, on the other hand, the rawness or greenness is not removed by an adequate heat, it masks the flavor of the bean, and injures the bev- erage made with it. When well roasted in the sheet-iron cylinders set to revolve over a fire, it should have a uniform chocolate color, a point readily hit by experienced roasters, who now manage the business very well for the principal coffee-dealers both of Londoa and Paris, so far as my judgment can determine. The development of the proper aroma is a criterion by which coffee roasters frequently^ regulate their operations^ When it loses more than 20 per cent of its weight, coffee is sure to be injured. It should never be ground till immediately before infusion. . , . ^ ^ i • Liebig's views of the process of nutrition have given fresh interest to every analysis of articles of food. A watery infusion of coffee is used in almost every country as a beveraee, and vet it is uncertain whether it is an article of nutrition or merely a con- diment A minute examination of the raw seed, or coffee bean as it is called, must precede the determination of that disputed point Caffeine is the principle best known, being most easily separated from the other substances, resisting most powerfully chemi- cal reagents, and by assuming a crystalline state is discoverable in very small quan- ^ The constituente of coffee are: 1. Vegetable Jihrine, which is the largest constituent, being an elastic horny substance, in which the other substances are incorporated. If we dry the beans at the heat of boiling water for several weeks we can easily reduce them to a fine powder, and by washing with ether, and then boiling in alcohol and water we extract the soluble matter from the fibrine, which may then be boiled with weak solution of potash and afterwards weak muriatic acid, as long as any matter is taken up. Ihe purification being completed by boiling in water the fibrine remains ; and when rub- bed in a mortar resembles starch ; when roasted it gives out the odor neariy of ^ood. 2 Fatty matter: the beans digested in ether give out a yellow-colored matter, vyhich on evaporation becomes buttery with an odor of raw coffee, and amounts to lOg of the 3. Caffeine : the ethereal solution contains caffeine, which may be removed by shaking with a solution of water. , , ^. .^. xv. -j 4. Legumine: in addition to an acid which agrees in it« properties with the acid found in oak and cinchona, we find in the coffee beans legumine similar to that of beans. The legumine contains sulphur, which is the cause of their blackening a silver vessel in whichthe beans may be boiled with an alkali. Legumine and caffeine are the only ni- trogenous constituents of coffee beans, consequently the only substances which could be nuU-itious, but they are not soluble in hot water as they exist in roasted coffee, and therefore it may be reckoned merely an exhilarating beverage. Roasted coffee affords a much richer infusion to hot water containing a minute quan- tity of carbonate of soda, and improves Uie quality of coffee on the stomach, by neu- 'tralizing the caffeic acids. j i- i. j -au • Coffee is sold in the shops in ite roasted and ground state often adulterated with a variety of substances, but chiefly with chicory. This is the dried, roasted, and ground root of a plant called Cichoriwn Intybun, better known under the name of wild succory. The chicory imported from Belgium and Prussia is better than the British, which is usually colored with Venetian red, and is sold at a cheaper rate ; chicory itself is fre- quently very impure, containing roasted peas and coffee flighta, which are the mena- branous coat of the bean separated in the act of roasting. If a little genuine ground coffee be thrown in a wineglassfull of water, it mostly floats, and slowly moistens, com- municating scarcely any color to the liquid. Powdered chicory treated in the same way very speedily absorbs moisture, communicates a deep reddish brown tint to the water, and in a few minutes falls to the bottom. Hambro' powder contains routed starch, and acquires a deep purplish color when moistened with a solution of iodine. The m'icroscope shows in the chicory powder fragments of dotted ducts which do not exist in coffee. There is another substance which is mixed with coffee, called refining powder; it is merely caramel, or burnt sugar. It is used /or enabling drained coffee to afford a dark colored infusion. . If tannin exists in roasted coffee, as maintained long ago by Chenevix, and generally admitted since, it must be very different from the tannin present in tea, catechu, kino, oak-bark, willow-bark, and other astringent vegetables; for I find that itjs °ot, like them, precipitated by either gelatine, albumen, or sulphate of quinine. With regard to the action upon the animal economy of coffee, tea, and cocoa, which contain one common chemical principle called caffeine or theine, Liebig has lately advanced some ingenious views, and has, in particular, endeavored to show that, to persons of sedentary habits in the present refined state of society, they afford eminently usdTul beverage^ which contribute to the formation of the characteristic principle of bile. This important secreted fluid, deemed by Liebig to be subservient to the function of respiration, requires for ite formation much azotised matter, and that in a state of coml.ination analogous to what existe in caffeine. The quantity of this principle in tea and coffee being only from 2 to 6 per cent might lead one to suppose that it could have little effect upon the system even of regular drinkers of their infusions; but if the bile contains only one-tenth of solid matter, called choleic acid, which contains less than 4 per cent of azote then it may be shown that 3 grains of caffeine would impart to 500 grams of 456 COFFEE. COLLODION. 457 • 1 I W-.* * I ) *i ■J bile th« uzote which occurs in that crystalline precipitate of bile called taurine, which is thrown down from it by by mineral acids. One atom of caffeine, 9 atoms of oxygen, and 9 of water, being placed together, produce the composition of 2 atoms of taurine. Now this is a very simple combina- tion for the living organism to eflFect; one already paralleled in the generation of hip- puric acid in urine, by the introduction of benzoic acid into the stomach ; a physiologi- cal discovery made by my son, which is likely to lead to a more successful treatment of some of the most formidable diseases of man, particularly gout and gravel. If the preceding views be established, they will justify the instinctive love of mankind for tea, coffee, and cocoa, in spite of the denunciations and veto of neuropathic, homect' pathic, and hydropathic doctors ; sorry pathologists — hoc genua omne. See Tea. In the years ending 5th January, 1851 and 1852, the imports of coffee were as fol- lows : — Importations. Entries for Hoin« Conaumption. Gross Amoant of Duty. 1851. 1852. 1851. 18.52. 1851. 1852. Entered before 15th April 1851 • or British FosBesaions Foreigm Entered from 15th April, 1851: from British PoBeessiona out of Europe From other Parts 36,814,036 13,989,116 • • Ibt. 1,818,514 5,018,806 34.077,563 12,0a'i,269 Ibi. 28,891,294 2,335,346 * * At. 6,510*346 443,418 21,486,170 4,124,230 505,.515 61,305 113,981 11,637 268,599 51,572 50,803,152 52,950,152 31,226,840 32,564,164 566,820 445,739 The duty is Zd per lb. Tlie exports in the above years were respectfully 12,169,762 lbs. and 22,712,859 lbs. of which 3,399,333 lbs. and 12,606,333 lbs. were the produce of British Possessions, and 8,770,419 lbs. and 10,106,526 lb& were Foreign. Coffee Roasting and Grinding. The gratefulness of the beverage afforded by this seed depends upon many circumstances, which are seldom all combined. The nature of the soil, the climate, seed, mode of culture, and cure, influence greatly the quality of the fruit But when all these particulars concur, and the berry is of the finest sort, and most highly appreciated by the im- porter, it may be ruined in the roasting ; for if some berries be under and some over done, the whole when ground will yield an unpalatable infusion. The due point to which the torrefaction should be carried, may be determined partly by the color, and partly by the loss of weight, which points, however, are dif- ferent for each sort of coffee. But perfect equality of ustulation is difficult of attain- ment with the ordinary cylindrical ma- chines. Messrs. Law, of London and Ed- inburgh, coffee merchants to the Queen, had long been dissatisfied with the partial manner in which the cylinder performed its duty, as it generally left some part of its contents black, some dark brown, and others paler ; results which greatly injure the flavor of the beverage made with the coffee. Mr. William Law has conquered all these difficulties by his happy invention of the globular roaster, actuated by a com- pound motion like that of our earth. This roaster, with its double, rotary motion, is neated not over an open fire but in an atmosphere of hot air, through a cast metal casing. The globe is so mounted as to revolve horizontally, and also from time to time vertically, whereby the included beans were tossed about and intermingled in all directions. In- equality of torrefaction becomes impossible. The consequence is the production of an article which on being ground evolves the most fragrant aroma, and when infused the most grateful and exhilarating beverage. The position of the globe in Jig. 866 shows ' it as turned up bv a powerful leverage out of the cast-iron heater, preparatory to its being emptied and re-charged. .,i i. i. v -:»^^*-i a*^«^ Tfe coffee, thus equally roasted, is finely ground in a mill between J^?"^««^^ «^"^^ like that of a corn-mill, and is thereby capable of giving out all its virtues to either boiling or cold water. , ^ , ,, , COKE is carbonized pitcoal. See Charcoal ; and Pitcoal at the end. In manufacturing coke on the large scale, Mr. Wilkinson of Jarrow. near Gates, head, has contrived a system of machinery for saving manual labor in discharging the coke from the ovens, while he has so arranged the ovens themselves, as to equalize the distribution of air among the coals, and to improve the produce and increase ito quantity. The preferable size of oven, in his opinion, is 14 feet long, 8 feet wide with 3ie floor raised one foot above the level of the ground, and having an inclination to the front of 6 inches in the length of the bottom ; the perpendicular height of the wall^ up U) the springer, being 3 feet, while the radius of the arch is 4 feet He connecte crystallizing and evaporating pans for chemical purposes with a range of 12 coke ovens. The patentee claims as inventions his forming in the walls of coke ovens, flues with lateral openings for supplying air to the interior of the oven as also his peculiar mechanical apparatus for discharging the coke, and his plan of economizing heat by ^^COLCOTHAR OF VITRIOL {Rouge d'Angleterre, Fr.; Bothes Eisenoxgd, Germ.) is the brown-red peroxide of iron, produced by calcining sulphate of iron with a strong heat, levigating the resulting mass, and elutriating it into an impalpable pow- der. A better way of making it so as to complete the separation of the acid, is to mix 100 parts of the green sulphate of iron with 42 of common salt to calcinethe mixture, wash away the resulting sulphate of soda, and levigate the residuum. The sulphurw acid in this case expels the chlorine of the salt in the form of muriatic acid gas, and saturates its alkaline base produced by the chemical reaction; whence an oxide willbe obtained free from acid, much superior to what is commonly found m the shops. Ihe best sort of polishing powder, called jeweller's red rouge, or plate powder, is the precipi- tated oxide of iron prepared by adding solution of soda to solution of copperas, washing, drying, and calcining the powder in shallow vessels with a gentle heat UU it assumes a deep brown-red color. See Iron. ^ a ^ xu t? v -m .4- «i COLLODION. M Malgaigne has recently communicated to the l^rench Medical Journals, some remarks on the preparation of gun-cotton for surgical purposea. Several French chemists, at the suggestion of M Malgaigne, attempted to make an ethereal solution of this compound, by pursuing the process recommended by Mr. Mavnard in the American Journal of Medical Sciences, but they failed in procuring the cotton in a state in which it could be dissolved in ether. It appears that these experi- mentalists had employed a mixture of nitric and sulphuric acids ; but M. Miallie ascer- tained, after many trials, that the collodion, in a state fitted for solution, was much more easily procured by using a mixture of nitrate of potash and sulphuric acid. For the information of our readers who may be disposed to try this new adhesive material, we here give a description of M. Miallie's process for ite preparation. U appears from the results obtained from this chemist that cotton, in its most explosive form, is not the best fitted for making the ethereal solution- Parts by weight. - 40 Finely powdered nitrate of potash Concentrated sulphuric acid - Carded cotton - 60 - 2 Mix the nitrate with the sulphuric acid in a porcelain vessel, then add the cotton, and agitate the mass for three minutes by the aid of two glass rods. Wash the cotton, with- out first pressing it, in a large quantity of water, and when all acidity is removed (indicated by litmus paper) press it firmly in a cloth. Pull it out into a loose mass, and drv it in a stove at a moderate heat ' It in a stove ai a muuemi-c iicov. .. rhe compound thus obtained is not pure fulminating cotton ; it always retains a small quantity of sulphuric acid, is less inflammable than gun-cotton, and it leaves a carbo- naceous residue after explosion. It has, however, in a remarkable degree, the property of solubility in ether, especially when mixed with a little alcohol, and it forms there- with a very adhesive solution, to which the name of collodion has been applied. Preparation of Collodion. Prepared cotton Rectified sulphuric ether Rectified alcohol Parts by weight 8 - 125 8 Put the cotton with the ether into a well-stopped bottle, and shake the mixture lot some minutes. Then add the alcohol by degrees, and continue to shake until the whole I 458 COLORS. ill 11 i ■ 'f ■» . ■ I I .V i> ;! 4^ 00 H H S •J 09 ¥^ H •J ta a: o H M Eh O » H § H »4 -< 03 D 09 OS o c S) ■ e u S5J8 . 6.^ ell ti- ll h 11 *»- 5 = S S 3 -= 2 •ST a k M=^ 15 i COLORS. 459 I f :l fa's a ml * «» •» t c - — •o — .« o • "0.« a • ■S'^ a S I I 8 ■3 3 ■sz a a u a 8 £.« c • .= . ■ w «• u ^ O 3 4i n S5 so" a " J7 fc a f - £ i- III III i«5 s ^ ■O ». 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I it ii'. of the liquid acquires a syrupy consistency. It may be then passed through a cloth, the residue strongly pressed, and the liquid kept in a well-secured bottle. Collodion thus prepared possesses remarkably adhesive properties. A piece of linen or cotton cloth covered with it and made to adhere by evaporation to the palm of the hand, will support a weiglit of twenty or thirty pounds. Its adhesive power is so great that the cloth will commonly be torn before it gives way. The collodion cannot be regarded as a perfect solution of the cotton. It contains suspended and floating in it a quantity of vegetable fibre, which has escaped the solvent action of the ether. The liquid portion may b^ separated from these fibres by a filter, but it is doubtful whether this is an advantage. In the evaporation of the liquid, these undissolved fibres by felt- ing with each other appear to give a greater degree of tenacity and resistance to the dried mass. In the preparation of collodion it is indispensable to avoid the presence of water, as this renders it less adhesive; hence the ether as well as the alcohol should be purely rectified. The parts to which the collodion is applied should be first thoroughly dried, and no water allowed to come in contact with them until all the ether is evaporated to dryness by a steam heat, which must be continued for some time so as entirely to expel the alcohol or ether. The residuary matter shouldl have the transparency and general characters of common resin. COLOPHANY, black rosin, the solid residuum of the distillation of turpentine, when aU the oil has been worked off. COLORING MATTER. (Matilre colorante, Fr. ; Farbstoff, Germ.) See Dyeing, the several dye-stuffs and pigments. COLUMBIUM, a peculiar metal extracted from a rare mineral brought from Haddam, in Connecticut. It is also called Tantalium, from the mineral tantalitf. and yttro-tantaliUf found in Sweden. It has hitherto no application to the arts. It combines with two suc- cessive dose? of oxygen ; by the second it becomes an acid. COLZA is a variety of cabbage, the hrassica oleraceay whose seeds afford, by pressure, an oil much employed in France and Belgium for burning in lamps, and for many other purposes. This plant requires a rich but light soil ; it does not succeed upon either sandy or clayey lands. The ground for it must be deeply ploughed and well dunged. It should be sown in July, and be afterward replanted in a richly-manured field. In October it ia to be planted out in beds, 15 or 18 inches apart. Colza may also be sowed in furrows 3 or 10 inches asunder. Land which has been just cropped for wheat is that usually destined to colza ; it may be fresh dunged with advantage. The harvest takes place in July, with the sickle, a little before the seeds are completely ripe, lest they should drop off. As the seed is pro- ductive of oil, however, only in proportion to its ripeness, the cut plants are allowed to complete their maturation, by laying them in heaps imder airy sheds, or placing them in a stack, and thatching it with straw. The cabbage-stalks are thrashed with flails, the seeds are winnowed, siAed, spread out in the air to dry ; then packed away in sacks, in order to be subjected to the oil- mill at the beginning of winter. The oil-cake is a very agreeable food to cattle, and serves to fatten them. It is reckoned to defray the cost of the mill. Colza impoverishes the soil very much, as do, indeed, all the plants cultivated for the lake of their oleaginous seeds. It must not, therefore, be come back upon again for sii years, if fine crops be desired. The double ploughing which it requires effectuallj cleans the ground. See Oils, Unctuous. COMB, the name of an instrument made of a thin plate either plane or curved of wood, horn, tortoise-shell, ivor}', bone, or metal, cut out upon one or both of its sides or edges, into a series of somewhat long teeth, not far apart«; which is employed for disentangling, laying parallel and smooth the hairs of man, horses, or other animals. A thin steel saw bow, mounted in an iron or wooden handle, is the implement used by the comb-maker to cut the bone, ivory, and wood into slices of from a twelfth to a quarter of an inch thick, and of a size suitable to that of the comb. The pieces of tortoise-shell as found in commerce are never flat, or, indeed, of any regular curvature, such as the comb must have. They are therefore steeped in boiling water sufiiciently long to soften them, and set to cool in a press between iron or brass moulds, which im- part to them the desired form which they preserve after cooling. After receiving their outline shape and curvature, by proper flat files or fine rasps, the place of the teeth is marked with a triangular file, and then the teeth themselves are cut out with a double saw, composed of two thin slips of tempered steel, such as the main-spring of a watut, notched with very fine sharp teeth. These slips are mounted in a wooden or iron stock or handle, in which they may be placed at different distances, to suit the width of the comb-teeth. A comb-maker, however, well provided in tools, has an assortment of double saws set at every ordinary with. The two slips of this saw have their teeth in different planes, so that when it begins to cut, the most prominent slip alone acts, and COMBUSTIBLE SUGAR. 461 when the teeth of this one have fairly entered into the comb, the other parallel blade begins to saw. The workman, meanwhile, has fixed the plate of tortoise-shell or ivory between the flat jaws of two pieces of wood, like a vice made fast to a bench, so that the comb intended to be cut is placed at an angle of 45'* with the horizon. He now saws perpendicularly, forming two teeth at a time, proceeding truly in the direction of the first tracinfir. A much better mode of making combs is to fix upon a shaft or arbor in a lathe a se- ries of circular saws, with intervening brass washers or discs to keep them at suitable dis- tances ; to set in a frame like a vice, in front of these saws, the piece of ivory or horn to be cut ; and to press it forward upon the saws at an angle of 45 degrees, by means of a regulated screw motion. When the teeth are thus cut, they are smoothed and polished with files, and by rubbing with pumice-stone and tripoli. Mr. Bundy, of Camden Town, obtained a patent so long ago as 1796, for an apparatus of that kind, which had an additional arbor fitted with a series of circular saws, or rather files, for sharpening the points of the comb-teeth. More recently, Mr. Lyne has invented a machine in which, by means of pressure, two combs are cut out at once with chisels from any tough material, such as horn or tortoise- shell, somewhat softened at the moment by the application of a heated iron to it. The piece of horn is made fast to a carriage, which is moved forward by means of a screw until it comes under the action of a ratchet-wheel, toothed upon a part of its circum- ference. The teeth of this wheel bring a lever into action, furnished with a chisel or knife, which cuts out a double comb from the flat piece, the teeth of which combs arc opposite to each other. By this means, no part of the substance is lost, as in sawing out combs. The same carriage may be used, also, to bear a piece of ivory in the hard state toward a circular saw, on the principles above explained, with such precision, that from 80 to 100 teeth can be formed in the space of one inch by a proper disposition of the tool. Bullocks* horns, after the tips are sawed off, are roasted in the flame of a wood fire, till they are sufficiently softened ; when they are slit up, pressed in a machine between two iron plates, and then plunged into a trough of cold water, whereby they are hard- ened. A paste of quicklime, litharge, and water is used to stain Uie horn to resemble tortoise-shell. See Horn. , . , »• ». COMBINATION {Comhinaison, Fr. ; Verbindungy Germ.) ; a chemical term whicl denotes the intimate union of dissimilar particles of matter, into a homogeneous-look- ing compound, possessed of properties generally different from those of the separate constituents. COMBUSTIBLE (Eng. and Fr. ; Brennstoff, Germ.) ; any substance which, exposed m the air to a certain temperature, consumes spontaneously with the emission of heal and light. All such combustibles as are cheap enough for common use go under the name of Fuel ; which see. Every combustible requires a peculiar pitch of temperatore to be kindled, called its accendible point. Thus phosphorus, sulphur, hydrogen, carbu. reted hydrogen, carbon, each takes fire at successively higher heats. COMBUSTIBLE SUGAR When sugar is acted on by a mixture of nitric and sulphuric acids, a peculiar substance is produced, having a close resemblance to common resin, not only in its appearance and physical characters, but also in regard to its solubility in alcohol, ether, volatile oils, Ac, and insolubility in water. This substance is, however, extremely inflammable and explosive, and possesses many of the properties ascribed to the celebrated Greek fire. Its afiinity for alcohol and ether is so great that water will not remove these fluids from it "Not having yet succeeded in producing with it any definite basic compound which would enable me to control my results, J have not attempted its analysis. The only purposes to which I have applied it are to the formation of fusees for shells, and to the preservation of gunpowder and pyrotech- nical articles from damp and moisture. As a fusee, it ia easily lighted, burns with great regularity, and appears absolutely incapable of being extinguished, circumstances which would render it of great use in ricochet practice. As a means of preventing the mis- chievous effect of damp and moisture on gunpowder it is of great value. The best mode of application is to plunge the gunpowder for a few seconds into an alcoholic or ethereal solution of the sugar compound, then withdraw it and allow it to dry at a gentle heat, say 120° Fahr., though there is no danger of an explosion at 212°. In this way the gunpowder is covered by a coat of varnish easy of ignition and insoluble in water, which cannot therefore penetrate to the gunpowder, the explosive nature of which is rather augmented than diminished by this treatment An ethereal solution of gun-cotton does not answer so well for this purpose, nor is it so manageable. I have not ascertained how far this new substance is useful in retaining the edges of wounds in approximation, but its alcoholic solution merits a trial. The following is the method which I have found most successful in the manufacture of this compound : — - .. . "Mix together sixteen parts of concentrated sulphuric acid and eight parts of nitnc 462 CONCRETE. COOLING OF FLUIDS. 463 acid, gpec grav. 1'50; place the mixture in cold water, and when the temperature has fallen to 60° or less, stir in one part of finely-powdered sugar, which will become pasty m a few seconds, and is then to be removed and plunged in cold water, when more sugar may then be added to the acid mixture, and removed as before. The compound is to be washed in water and dissolved in alcohol, to which a solution of carbonate of potash must be added in excess, so as to precipitate the substance, and neutralize its uncom- bined acid. After careful washing with water, it is again to be dissolved in alcohol or ether, and cautiously evaporated to dryness by a steam heat, which must be continued for some time, so as entirely to expel the alcohol or ether. The residuary matter should have the transparency and general character of common rosin."— J/r. i. Thompson. COMBUSTION (Eng. and Fr.; Verbrennuna, Germ.) results in common cases from the mutual chemical reaction of the combustible, and the oxygen of the atmosphere, whereby a new compound is formed ; the heat and light evolved being most probably produced by the rapid motions of the particles during the progress of this combination. COMPOUND COLORS. If the effects of the coloring particles did not vary aceord- ing to the combinations which thev form, and the actions exercised upon them by the different substances present in a dyeing bath, we might determine with precision the §hade which ought to result from the mixture of any two colors, or of the ingredients affording these colors separately. Though the chemical action of the mordants and of the liquor in the dye-bath often changes the result, yet theory may always predict thera within a certain degree. It is not the color appropriate to the dye-stuffs which is to be considered as the constituent part of compound colors, but that which they must assume with a certain mordant and dye-bath. Our attention ought therefore to be directed principally to the operation of the chemical agents employed. 1. The mixture of blue and yellow dyes produces green. D'Ambourney, indeed, Mys that he has extracted a fast green from the fermented juice of the berries of the buckthorn {rhamnu* fragula), but no dyer would trust to such a color. 2. The mixture of red and blue produces violet^ purple, columbine (dove-color), pansy, amaranth, lilac, mallow, and a great many other shades, determined by the na- ture and tone of the red and blue dye-stuffs, as well as their relative proportions in the bath. 3. The mixture of red and yellow produces orange, mordore, cinnamon, coquelicoU brick, capuchin; with the addition of blue, olives of various shades ; and with duna instead of yellows, chestnut, snuff, musk, and other tints. 4. Blacks of the lighter kinds constitute grays; and, mixed with other colors, pro- duce marrone (marroons), coffees, damascenes. For further details upon this sub- jecti see Calico Feinting, Dyeing, as also the individual colors in their alphabetical plaees. CONCRETE. The name given by architects to a compact mass of pebbles, sand, »nd lime cemented together, in order to form the foundations of buildings. Semple lays that the best proportions are 80 parts of pebbles, each about 7 or 8 ounces in weight, 40 parts sharp river sand, and 10 of good lime ; the last is to be mixed with water to a thinnish consistence, and grouted in. It has been found that Thames ballast, as taken from the bed of the river, consists nearly of 2 parts of pebbles to 1 of sand, and therefore answers exceedingly well for making concrete ; with from one seventh to one eighth part of lime. The best mode of making concrete, according to Mr. Godwin, is to mix the lime, previously ground, with the ballast in a dry state ; sufficient water is now thrown over it to effect a perfect mixture, after which it should be turned over at least twice with shovels, or oftener; then put into barrows, and wheeled away for use instantly. It is generally found advisable to employ two sets of men to perform (his operation, with three in each set; one man to fetch the water, &.C., while the other two turn over the mixture to the second set, and they, repeating the process, turn over the concrete to the barrow-men. After being put into the barrows, it should at once be wheeled up planks, so raised as to give it a fall of some yards, and thrown into the foundation, by which means the particles are driven closer together, and greater solidity is given to the whole mass. Soon after being thrown in, the mixture is observed usually to be in commotion, and much heat is evolved with a copious emission of vapor. The barrow-load of concrete in the fall, spreading over the ground, will form generally a stratum of from 7 .x) 9 inches thick, which should be allowed to set before throwing in a second. Another method of making concrete, is first to cover the foundation with a certain quantity of water, and then to throw in the dry mixture of ballast and lime. It is next turned and levelled with shovels ; afler which more water is pumped in, and the operation is repeated. The former method is undoubtedly preferable. In some cases it has been found necessary to mix the ingredients in a pug-mill, as in mixing clay, &c. for bricks. For the preparation of a concrete foundation, as the harden- ing should be rapid, no more water should be used than is absolutely necessary to effect a perfect mixture of the ingredients. Hot water accelerates the induration. There is about one fifth of contraction in volume in the concrete, in reference to the bulk of ita ingredients. To form a cubical yard of concrete, about 30 feet cube of ballast and S| feet cube of ground lime must be employed, with a sufficient quantity of water. CONGELATION (Eng. and Fr. ; Ge/rierung, Germ.); the act of freezing liquids. Many means are supplied by chemistry for effecting or promoting this process, but they do not constitute any peculiar art or manufacture. See Ice-Housk. COOLING OF FLUIDS. In Mr. Derosnes's method, the cooling agents employed are a current of atmospheric air, and warm water of the same or nearly the same tem- perature as that of the vapors which are to be operated upon. Fig. 867 represents merely a diagram of the general features of ftn apparatus con- ilructed upon the principles proposed to be employed, which will serve to explain the nature of this improvement. 367 Let A be the source of fK. |] the vapors, or the vessel, boiler, alembic, or closed pan that contains the liquid or sirup to be eva- porated or concentrated. The pipe b, through which the vapor passes as it rises in the boiler, is sur- rounded by another tube c,of larger diameter, closed at both ends. A pump d, draws from the reservoir e, warm water, which water has been heated by its pre- vious and continual pas- sage through . the appa- ratus m contact with the surface of the vapor pipes. This pump forces the water by the pipe f, into the annular space or chamber between the pipes B and c, in which chamber, by its immediate contact with the pipe b, it acquires the temperature of the vapors intended to be refrigerated. The pipe g conveys th** water from the pipe c, into the annular colander or sieve H, which has a multitude of ^iinall holes pierced through its under part, and whence the warm water descends in the form of a continued shower of rain. To the end of the pipe b, a distiller^s worm i i, is connected, which is placed beneath the colander h. The entire length of the worm-pipe should be bound round with linen or cotton cloth, as a conductor of the heat, which cloth will be continually moistened by the rain in its descent from the colander. As this water has been heated in passing along the tube c, the shower of rain descending from the colander will be at a higher temperature than that of the atmosphere, and, consequently, by heating the surrounding air as it descends, a considerable upward draft will be produced through the coils of the worm-pipe. If the colander and the worm-pipe are enclosed within a chimney or upright tube, as K Kj open at top and bottom, a current of ascending air will be produced within it by the descending shower of hot water, similar in effect to that which would be produced in a chimney communicating with a furnace, or to that of the burner of an argana lamp. Consequently, it will be perceived that in opposition to the descending rain, a strong upward current of air will blow through that part of the cylinder k k, which is beneath the colander. When the air first enters the lower aperture of the chimney oi tube K, it is of the same temperature and moisture as the external atmosphere ; but in its passage up the tube it meets with a warmer and damper atmosphere, caused by the heat given out from the hot fluid continually passing through the pipes, and by the hot shower of rain, and also by the steam evolved from the surfaces of the coils of the worm, which are continually wetted by the descending rain, the evaporation being considerably augmented by th« cloth bound round the worm-pipe, retaining the water as it descends in drops from coil t^ coil. The atmosphere within the tube being of a higher temperature than without, a current of air constantly ascends and escapes at the upper aperture k, and its place is supplied by fresh air from the surroundin? atmosphere, entering the tube below. The fresh air thus admitted at the bottom of the lube, being cold and dry, will be suited to take up the heat and moisture within, because the water within the tube, being in a state of dispersion as rain, presents to the air many points, or a very extended surface, an<{ also because it is of a higher temperature than the air ; and, besides, cold dry air is cow inually renewed, and a source of warmth is furnished by the latent caloric to the 464 COOLING OF FLUIDS. COPAL. 465 iteara, as fast as it is evolved. Thus a portion of the descending rain, or water, ia evaporated, and the effect of this evaporation is to abstract caloric not only from the ^ater held in contact with the coils of the worm-pipe by the cloth enveloping it, but also from the hot vapors which pass through the worm. This process of evaporation has, therefore, a cooling power, which is but slight in the lower part of the chimney or tube K, because the temperature of the water, or rain, and of the worm, at this part, are of a lower temperature; but its refrigerating power increases as it rises towards the colander, and there it acquires its maximum of intensity, so that at any point between the lower aperture of the cylinder and the colander the current of air is always a little cooler than the atmosphere of the region through which it passes (that is, as its maxi- mum); and in passing this region of higher temperature, it is not only put in equili- Dnum of temperature, but also made to take up an additional quantity of aqueous vapors, which equalizes the new temperature it acquires with its capacity of saturation. The cooling caused by the evaporation acts in an incessant and progressive manner from the lower aperture of the cylinder to the under side of the colander ; and this cooling not only acts as an agent of the evaporation which the current of air cools, but it refrige- rates also, because it becomes warmed in abstracting caloric from the vapors or liquidt passing through the worm ; and this refrigeration acts also incessantly and progressively from the lower part of the tube or chimney to the colander. The patentee states, in conclusion, that « the velocity or force of the current of air that passes through the chimney or tube k, can be accelerated by artificial means, either by conducting the air and vapor passing from the upper aperture of the cylinder into the chimney or flues of a furnace, or by means of a revolving, forcing, or exhausting fan, or ventilator, or any other contrivance which will produce an increased current of air, but which is not necessary to be particularly described, as I only wish to explain the prin- ciples of a simple apparatus, constructed in any convenient form ; and I would remark, tkat the area of the lower aperture through which the air is introduced into the chimney or tube k, and also the area of the upper aperture, or that through which it passes to the atmosphere, should be in accordance with the effect intended to be obtained. " It is further to be remarked, that in order to obtain from this apparatus the best efl'ect, the velocity of the current of air must be itself a maximum ; and as the speed or velocity of the current of air is owing to and determined by the excess of the tempe- rature of the descending water, or rain, and of the coils of the worm to that of the exterior atmosphere, it ensues that the temperature of the water, or rain, must be a maximum. But this excess of temperature is a maximum only when the source of the rain is at the same temperature as the vapors to be condensed : if less warm, it would attract less air ; or, if warmer, it would augment the temperature of the vapors intended to be condensed. Consequently, the shower of water employed in the tube k, as the agent for cooling, bestows its maximum of effect when it is as warm as the vapors to be condensed ; therefore, I may express this proposition, viz., < That in refrigerating with water, less of it may be expended when it is warm than when it is cold, and that the least quantity of water will be evaporated when it is as warm as the aqueous or spirituous vapors upon which it is to operate.' " This proposition may appear strange, nevertheless it is conformable to the laws of nature ; and appears only strange, because until now warm water has not been employed with currents of air for refrigerating. " Hence it is necessary to raise the temperature of the water in the colander to the temperature of the vapors to be condensed : therefore, I cause the lukewarm water, pumped from the reservoir e, to circulate in the chamber c. In this circulation it also begins to act as a refrigerating medium, taking up a portion of heat from the vapors that pass through the pipe b, and afterwards it acts as a further condenser in the cylinder, in the way described. Finally, the portion of this water that is still in the fluid state, after having fallen down from coil to coil, arrives lukewarm to the inclined surface l, which conducts it mto the reservoir e, from whence it is pumped up into the chamber c, as before described. "The tube or chimney k may have more or less altitude; the higher it is the greater IS the current produced. The force or velocity of the current of air can be governed by the areas of the introduction and exit apertures. If the cylinder rises only to the height of the sieve, the effect is much less than when it is prolonsed beyond this height. I would further remark, that if the cylinder was removed, a slight effect mi?ht be pro- duced, provided that a current of air be preserved in the cylindrical space limited by the toils of the worm, and also if the current was produced between the coils ; or a central passa^re might be formed in an apparatus of another shape than that above described. " I have only shown the application of the worm, because intending only to explain the principles of this method of condensing and refrigerating. « The small quantity of water wasted in this manner of condensation, (that is, that portion passed off to the atmosphere in the form of vapors, at the upper aperture of the cylinder k), may be replaced by a small stream of cold water, which may be brought to the apparatus, and perhaps most conveniently introduced into the reservoir k, or into the chamber between the pipes b and a When operating upon aqueous \napor8, the waste of waters is always less in weight than that of the vapors liquefied. When this apparatus is applied to the purposes of distillation, the end of the worm should termi- nate in a vessel m, which is to receive the produce of the condensation. It will be seen that this improved process is applicable to various purposes, where condensation or refrigeration is required; for instance, in the boiling or concentration of sugar; to con- densing and refrigerating distilled vapors, or steam, or saline liquids, either in vacuum or not ; to cooling brewers' worts ; and to the refrigeration of other liquors, or any other processes, when it may be required." I have inserted the specification of this patent verbatim. M. Derosne has busied him- self during a long life with a prodigious number of ingenious little contrivances for clarifying and boiling syrups, distillation, &c., but he has in this invention taken a bolder flight, having secured the exclusive privilege of condensing vapors, and cooling liquors, with hot water, in preference to cold. Ko man at all versant in the scientific doctrines, or the practical applications of caloric, will ever seek to meddle with his mo- nopoly of such a scheme. He may find, perhaps, some needy coppersmith ready to espouse that or any other equally foolish project, provided a productive job can be made of it, against credulous customers. For some rational methods of cooling liquors and condensing vapors, see Refrigeea- TiON, Still, and Sugar. COPAL, a resin which exudes spontaneously from two trees, the Ithtts copallinum^ and the Elaocarpus copali/er, the first of which grows in America, and the second in the East Indies. A third species of copal-tree grows on the coasts of Guinea, especially on the banks of some rivers, among whose sands the reein is found. It occurs in lumps of various sizes and of various shades of color, from the palest greenish yellow to darkish brown. I found its specific gravity to vary in different specimens from 1-059 to 1-071, being intermediate in density belween its two kindred resins, anim6 and amber. Some rate its specific gravity so high as 1-139, which I should think one of the errors with which chemical compilations teem. Copal is too hard to be scratched by the nail, whence the excellence of its varnish. It has a conchoidal fracture, and is without smell or taste. When exposed to heat in a glass retort over a spirit lamp, it readily melts into a liquid, which being further heated boils with explosive jets. A viscid, oily-looking matter then distils over. After continuing the process for some time, no succinic acid is found in the receiver, but the copal blackens in the retort. Anhydrous alcohol boiled upon it causes it to swell, and transforms it by degrees into an elastic, viscid substance. It is not soluble in alcohol of 0825 at the boiling point, as I have ascer- tained. Copal dissolves in ether, and this ethereous solution may be mixed with alco- hol without d€composition. Caoutchoucine acts very slightly upon it by my experi- ments, even at the boiling temperature of this very volatile fluid ; but a mixture of it with alcohol of 0*825, in equal parts, dissolves it very rapidly in the cold into a perfectly liquid varnish. Alcohol holding camphor in solution also dissolves it, but not nearly so well as the last solvent According to Unverdorben, copal may be completely dissolved by digesting one part of it for 24 hours with one part and a half of alcohol (probably an- hydrous), because that portion of copal which is insoluble in alcohol dissolves in a very concentrated solution of the soluble portion. Oil of petroleum and turpentine dissolve only 1 or 2 per cent of raw copal. By particular management, indeed, oil of turpentine may be combined with copal, as we shall describe under the article Varnish. Fused copal possesses different properties from the substance in its solid state; for it then may be made to combine both with alcohol and oil of turpentine. Unverdorben has extracted from the copal of Africa five different kinds of resin, none of which has, however, been applied to any use in the arte. The ultimate constituents of copal by my analysis are, carbon Y9*8Y, hydrogen 9-00, oxygen ll'l; being of hydrogen 7-6 in excess above the quantity necessary to form water with the oxygen. Much information has been received from various sources concerning this somewhat ill-understood product of late years. It is now known that there are three different kinds of copal in commerce, but nothing is known of their distinguishing characteristics. We have East Indian and West Indian copal, and, under the latter name, two very dif- ferent substances The East Indian, called also African, is more colorless, soft, and trans- parent, than the others; it forms a fine surface, and when heated emits an agreeable odor. It furnishes the finest varnish. Fresh essence of turpentine dissolves it com- pletely, but not old. Essence digested upon sulphur will dissolve double its own weight, without letting any fall. Fresh rectified oil of rosemary will dissolve it in any propor- tion, but if the oil is thickened by age it serves only to swell this copaL 30 466 COPPER. COPPER. 467 When cautiously melted, it may be then dissolved in good esaencc of turpentine in any proportion, producing a fine varnish, of little color. A good varnish may be made by dissolving 1 part of copal, 1 of essence of rosemary, "with from 2 to 3 of pure alcohol This varnish should be applied hot, and when eold becomes very hard and durable. The West India species, or American, comes to us, not in lumps of a globular form, but in small flat fragments, which are hard, rough, and without taste or smelL It ia usually yellow, and never colorless"^ like the other. Insects are very rarely found in it It comes from the Antilles, Mexico, and North America. It will not dissolve in essence of rosemary. The third kind of copal, known also as West Indian, was formerly sold as a product of the East Indies. It is found in fragments of a concavo-convex form, the outer cover- ing of which appears to have been removed. It contains many insecta When rubbed it emits an aromatic odor. It gives out much ethereous and empyreumatic oil when melted. It forms a soft varnish, which dries slowly. Fusel oil, or amyle spirit, has been lately used as a solvent of the hard copal ; but it does not dry into a very solid varnish. Annexed is an account of the import of anim4 and copal, in the undermentioned years : — 1841. 1842. 184a 1844. Quantities imported cwta — 8336 8359 6493 Quantities exported cwts. — 1403 1508 2461 Retained for consumption cwts. — 2091 2085 2770 Nett revenue £ 536 296 117 167 COPPER is one of the metals most anciently known. It was named from the inland of Cyprus, where it was extensively mined and smelted by the Greeks. It has a red- dish brown color inclining to yellow : a faint but nauseous and rather disagreeable taste ; and when rubbed between the fingers it imparts a smell somewhat analogous to its taste. Its specific gravity is from 8*8 to 8*9. It is much more malleable than it ia ductile ; so that far finer leaves may be obtained from it than wire. It melts at the 27th degree of Wedgewood's pyrometer, and at a higher temperature it evaporates in fumes which tinge the flame of a bluish green. By exposure to heat with access of air, it is rapidly converted into black scales of peroxide. In tenacity it yields to iron; but surpasses gold, silver, and platinum, considerably in this respect In mineralogy, the genus copper includes about 13 different species, and each of these contains a great many varieties. These ores do not possess any one general exterior character by which they can be recognised ; but they are readily distinguished by chem- ical re-agents. Water of ammonia digested upon any of the cupreous ore in a pulver- ized state, after they have been calcined either alone or with nitre, assumes an mtense blue color, indicative of copper. The richest of the ordinary ores appear under two aspects: the first class has a metallic lustre, a copper red, brass yellow, iron gray, or blackish gray color, sometimes inclining to blue ; the second is without metallic appear- ance, has a red color, verging upon purple, blue, or green, the last tint being the most usual Few copper ores are to be met with, indeed, which do not betray the presence of this metal by more or less of a greenish film. Dr. Scherer, of Freybei^, has arranged the ores of copper as follows : — Symbol. 1. Copperglanz (Kupferglaserz) CuaS 2. Kupferkies, Copper pyrites, Cu^, FcaSs 3. Buntkupfererz 3 Cu^, FeSs 4. Fahlerz 4 (CujS, FeS, ZnS, AgS (Sb Ss As S,) 5. Rothkupfererz CujO 6. Malachit 2 CuO, COj-f-HO 7. Kupferlasur (2 (CuO, C02)-}-CuO. HO Copper in lOOL 79-7 84-8 56-7 14—41 88-5 57-4 65-8 Both Fahlerz and Buntkupfererz vary greatly in their proportion of copper. Fablers is very difficult to convert into pure copper by smelting, on account of tne presence of antimony and arsenic in it Kupferglanz is a disulphuret of copper. Buntiupfererz is purple or variegated copper ore. Rothkupfererz is the orange or red oxide of copper. Kuferlasur is blue carbonate of copper. Pure copper majr be obtained in the solid state either by the reduction of the pow- der of the pure oxide by a stream of hydrc^en gas passed over it in an ignited' tube, or by the galvanoplastic process. See Electro-metallurgy, or Electrottpie. 1. Native Copper occurs in crystals, branches, and filaments, its most common lo- cality bein^ in primitive rocks. It is found abundantly in Siberia, at the mines of Tourinski, m those of Hungary, of Fundo-Moldavi in Gallicia, of Fahlun in Sweden. of Cornwall, &«. The gangues of native copper are granite, gneiss, mica-slate, clay slate, quartz, carbonate or fiuate of lime, sulphate of barytes, &c. The most remarka- ble masses of native copper hitherto observed were — first, one in Brazil, 14 leasues from Basa, which weighed 2616 pounds; and secondly, another which Dr. Francis-le-Baron discovered in America to the south of Lake Superior. It was nearly 15 feel in circum- ference. 2. Sulphuret of Copper^ the vitreous ore of Brochani. The texture of this ore is conv- pict; its fracture, conchoidal, surface sometimes dull ; color, iron black or lead gray, often bluish, iridiscent, or reddish from a mixture of protoxyde. It is easily melted even by the heat of a candle ; but more difficult of reduction than protoxyde. This ore yields to the knife, assuming a metallic lustre when cut. Its density varies from 4*8 to 5*34. Its composition, according to Klaproth, is 78*5 copper, 18*5 sulphur, with a little iron and silica. Its equivalent constitution by theory is 80 copper -[-20 sulphur = 100; whence 78-5 of metal should be associated with 19-6 of sulphur. This ore is therefore one of the richest ores, and forms very powerful veins, which likewise contain some orange pro- toxyde. It is to be found in all considerable copper districts ; in Siberia, Saxony, Sweden, and especially Cornwall, where the finest crystals occur. 3. Copper Pyrites resembles in its metallic yellow hue, sulphuret of iron ; but the latter is less pale, harder, and strikes fire more easily with steel. It presents the most lively rainbow colors. Its specific gravity is 4*3. It contains generally a good deal of iron, as the following analysis will show : copper 30, sulphur 37, iron 33, in 100 parts. Ac- cordmg to Hisinger, the Swedish pyrites contains 63 of copper, 12 of iron, and 25 of sul- phur. These ores occur in primitive and transition districts in vast masses and powerful veins ; and are commonly accompanied with gray copper, sulphuret of iron, sparry iron, fiulphurets of lead, and zinc. 4. Gray Copper has a steel gray color, more or less deep, either shining or dull ; frac- ture uneven; a distinct metallic lustre; diflicult of fusion at the blowpipe ; it communi- cates to glass of borax a yellowish-red color. Its density in crystals is 4*86. Its compo- sition is very variable ; consistins essentially of copper, iron, antimony, and sulphur. The exploration of this ore is profitable, in consequence of the silver which it frequently con- tains. It occurs in primitive mountains ; and is oAen accompanied with red silver ore^ copper pyrites, and crystallized quartz. 5. Protoxyde of Copper, or red oxyde of Copper : its color is a deep red, sometimes very lively, especially when bruised. It is friable, difficult of fusion at the blowpipe, re- ducible on burning charcoal, soluble with efiervescence in nitric acid, forming a green liquid. Its constitution, when pure, is 88*9 copper -|- 11*1 oxygen = 100. 6. Black oxyde of Copper is of a velvet black, inclining sometimes to brown or blue ; and it acquires the metallic lustre on being rubbed. It is infusible at the blowpipe. Its composition is, copper 80 -(-oxygen 20 ; being a true peroxyde. 7. Hydrosilicate of Copper consists essentially of oxyde of copper, silica, and water. Its color is green ; and its fracture is conchoidal with a resinous lustre, like most minerals which contain water. Its specific gravity is 2*73. It is infusible at the blowpipe alone, but it melts easily with borax. 8. Dioptase Copper, or Emerald Malachite ; a beautiful but rare cupreous mineral, con- sisting of oxyde of copper, carbonate of lime, silica, and water in varying proportions. 9. Carbonate of Copper, Malachite, is of a blue or green color. It occurs often in beautiful crystals. 10. Sulphate of Copper, Blue Vitriol, similar to the artificial salt of the laboratory The blue water which flows from certain copper mines is a solution of this salt. The copper is easily procured in the metallic state by plunging pieces of iron into it. 11. Phosphate of Copper is of an emerald green, or verdigris color, with some spots of black. It presents fibrous or tuberculous masses with a silky lustre in the fracture. It dissolves in nitric acid without eflTervescence, forming a blue liquid ; melts at the blow- pipe, and is reducible upon charcoal, with the aid of a little grease, into a metallic globule. Its powder does not color flame green, like the powder of muriate of copper. 12. Muriate of Copper is green of various shades; its powder imparts to flame a re- markable blue and green color. It dissolves in nitric acid without eflTervescence-; and is easily reduced before the blowpipe. Its density is 3*5. By Klaprolh's analysis, it con- tisis of oxyde of copper 73, muriatic acid 10, water 17. 13. ^rseniate of Copper. It occurs in beautiful blue crystals. Before the blowpipe it melts, exhaling fumes of a garlic odor, and it affords metallic globules when in contact with charcoal. See mere upon the ores at the end of this article. In the article Metallurgy, I have described the mode of working certain coppei mines ; and shall content myself here with giving a brief account of two cupreous forma- tions, interesting in a geological point of view ; that of the copper slate of Mansfeldt, and •f the copper veins of Cornwall. The curious strata of bituminous schist in the first of these localities, art among tht I ' 468 COPPER. I most ancient of any which contain the exuviae of organized bodies not testaceom. "From among their tabular slabs the vast multitudes of fossil fish were extracted, which have rendered the cantons of Mansfeldt, Eisleben, Ilmenau, and other places in Thuringia and Voigtland so celebrated. Many of the fish are transformed into copper pyrites. Here, also, have been found the fossil remains of the lizard family, called Monitors. Such is the influence of a wise administration upon the prosperity of mines, that the thin layer of slate m this formation, of which 100 pounds commonly contain but one pound and a half of copper, occasionally argentiferous, has been for several centuries the object of smelting works of the greatest importance to the territory of Mansfeldt and the adjoining country. The frequent derangements which this metallic deposite experiences, led skilful directors of the under-ground operations at an early period to study the order of superposition ol the accompanying rocks. From their observations, there resulted a system of facts whicH have served to guide miners, not only in the country of Man«,''°ldt, but over a great poi tion of Germany, and in several other countries where the sam« series of rocks, forming the immediate envelope of the cupreous schists, were found to occur in the same ordei of superposition. 0/ the English copper works. — ^The deposites of copper in Cornwall occur always IJ Teins in granite, or in the schistose rocks which surround and cover it ; and hence, the Cornish miners work mostly in the granite or greenish clay slate ; the former of which they call growan, the latter killas. But tin is sometimes disseminated in small veins in porphyry or elvauy which itself forms great veins in the above rocks. No stratification has been observed in Cornwall. The copper veins are abundant in the killas and rare in the granite ; but most numer- ous near the line of junction of the two rocks. The different kinds of mineral veins in Cornwall may be classed as follows : — 1. Veins of elvan ; el van courses, or elvan channels. 2. Tin veins, or tin lodes ; the latter word being used by the Cornish miners to signify a vein rich in ore, and the word course, to signify a barren vein. 3. Copper veins running east and west ; east and west copper lodes. 4. Second system of copper veins, or contra copper lodes. 5. Crossing veins ; cross courses. 6. Modem copper veins ; more recent copper lodes. 7. Clay veins ; of which there are two sets, the more ancient, called Cross-Fluckans ; and the more modem, called Slides, There are therefore three systems of copper veins in Cornwall ; of which the first is considered to be the most ancient, because it is always traversed by the two others, and because, on the contrary, it never cuts them off. The width of these veins does not ex- ceed 6 feet, though occasional enlargements to the extent of 12 feet sometimes take place. Their length is unknown, but the one explored in the United Mines has been traced over an extent of seven miles. The gangue of these veins is generaUy quartz, either pure, or mixed with green particles analogous to chlorite. They contain iron pyrites, blende, sul- phuret, and several other compounds of copper, such as the carbonate, phosphate, arse- niate, muriate, &c. The most part of the copper veins are accompanied with small ar- gillaceous veins, called by the miners fluckan of the lode. These are often found upon both sides of the vein, so as to form cheeks or salebandes. When two veins intersect each other, the direction of the one thrown out becomes an object of interest to the miner and geologist. In Saxony it is regarded as a general fact that the rejected portion is always to the side of the obtuse angle ; this also holds gener- ally in Cornwall, and the more obtuse the angle of incidence, the more considerable the out-throw. The great copper vein of Carharack, in the parish of Gwenap, is a most instractive example of intersection. The power of this vein is 8 feel ; it runs nearly from east to west, and dips toward the north at an inclination of 2 feet in a fathom. Its upper part is in the killas, its lower part in the granite. The vein has suffered two intersections ; the first results from encountering the vein called Steven's fluckan, which mns from north- east to south-west, throwing it out several fathoms. The second has been caused by another vein, almost at right angles to the first, and which has driven it 20 fathoms out to the right side. The fall of the vein occurs, therefore, in one case to the right, and in the other to the left ; but in both instances, it is to the side of the obtuse angle. This disposition is very singular ; for one portion of the vein appears to have ascended, while another has sunk. The mining works in the copper veins are carried on by reverse steps ; see Mines The grand shafts for drainage and extraction are vertical, and open upon the roof side of the vein, traversing it to a certain depth. These pits are sunk to the lowest point of the exploration ; and, in proportion as the workings descend, by means of excavations m the vein, the pits are deepened and put into communication toward their bottom with COPPER. 460 each new gallery of elongation, by means of transverse galleries. At present, the mail shafts are fully 160 fathoms deep. Their horizontal section is oblong, and is divided into two 4iompartments ; the one destined for extraction, the other for the pumps. Their tim- bering has nothing remarkable, but is executed with every attention to economy, the whole wood employed in these mines being brought from Norway. The descent of the workmen is effected by inclined shafts scooped out of the vein ; the ladders are slightly inclined; they are intermpted every 10 fathoms by floors; the steps are made of iron, and, to prevent them from turning under the foot, the form of a miner's punch or jumper has been given them, the one end being round, and the other being wedge-shaped. The ore is raised either by means of horse-gins, or by steam-engine power, most fire- quently of high pressure. I shall take the Consolidated Mines as an example. The draining, which is one of the most considerable sources of expense, both from the quantity of water, and from the depth of the mine, is executed by means of sucking and forcing pumps, the whole piston-rods of which, 120 feet long, are attached to a main-rod suspended at the extremity of the working beam of a steam-engine. On this mine three steam-engines are erected of very great power, for the purpose of drainage ; the one called the Maria engine is of the first-rate force, and most improved construction. The cylinder is 90 inches in internal diameter, and the length of the stroke is 9 feet 1 1 inches. It works single stroke, and is incased in a coating of bricks to prevent dissipation of the heat. The vapor is admitted at the upper end of the cylinder during the commencement of the fall of the piston, at a pressure capable of forming an equilibrium with a column of 60 inches of mercury. The introduction of the steam ceases whenever the piston has descended through a certain space, which may be increased or diminished at pleasure. During the remainder of the descent the piston is pressed merely by this vapor in its progressive expansion, while the under side of the piston communicates with the condenser. It ascends by the counterweight at the pump end of the working beam. Hence, it is only during the descent of the piston that the effective stroke is exerted. Frequently the stefiun is admitted only during the sixth part of the course of the piston, or 18 inches. In this way the power of the engine is proportioned to the work to be done ; that is, to the body of water to be raised. The maximum force of the above engine is about 310 horses ; though it is often made to act with only one third of this power. The copper mines of the Isle of Anglesey, those of North Wales, of Westmoreland, the adjacent parts of Lancashire and Cumberland, of the south west of Scotland, of the Isle of Man, and of the south east of Ireland, occur also in primitive or transition rocks. The ores lie sometimes in masses, but more frequently in veins. The mine of Ecton in Staffordshire, and that of Cross-gill burn, near Alston-moor in Cumberland, occur in transition or metalliferous limestone. Th6 copper ores extracted both from the granitic and schistose localities, as well as from the calcareous, are uniformly copper pyrites more or less mixed with iron pyrites ; the red oxyde, carbonate, arseniate, phosphate, and muriate of copper, are very rare in these districts. The working of copper in the Isle of Anglesey may be traced to a very remote era. It appears that the Romans were acquainted with the Hamlet mine near Holyhead ; but it was worked with little activity till about 70 years ago. This metalliferous deposite lies in a greenish clay slate, passing into talc slate ; a rock associated with serpentine and euphotide (gahbro of Von Buch). The veins of copper are from one to two yards thick, and they converge towards a point where their union forms a consideraWe mass of ore. On this mass the mine was first pierced by an open excavation, which is now upwards of 300 feet deep, and appears from above like a vast funnel. Galleries arc formed at different levels upon the flank of the excavation to follow the several small veins, which run in all directions, and diverge from a common centre like so many radiu The ore receives in these galleries a kind of sorting, and is raised by means of hand windlasses to the summit of a hill, where it is cleaned by breaking and riddling. The water is so scanty in this mine that it is pumped up by a six-horse steam-engine. A great proportion of it is charged with sulphate of copper. It is conveyed into reser- voirs containing pieces of old iron ; the sulphate is thus decomposed into copper of c©» mentation. The Anglesea ore is poor, yielding only from 2 to 3 per cent, of copper : a portion of its sulphur is collected in roasting the ore. Mechanical preparation of the copper ores in Cornwall. — The ore receives a first sort- ing, either within the mine itself, or at its mouth, the object of which is to separate all the pieces larger than a walnut. These are then reduced by the hammer to a smaller size ; after which the whole are sorted into four lots, according to their relative richness. The fragment? of poor ore are pounded in the stamps so that the metallic portion may be separated by washing. The rich ore is broken into small bits, of the size of a nut, with a flat beater, formal Ill . I I i 470 COPPER. of a piece of iton 6 inches square and 1 inch thick, adapted to a wooden handle. The ore to be bioken is placed upon plates of cast-iron ; each about 16 inches square and 1| inch thick. These iron plates are set towards the edge of a small mound about a yard high, constructed with dry stones rammed with earth. The upper surface of this mound is a little inclined from behind forwards. The work is performed by women, each furnished with a beater ; the ore is placed in front of them beyond the plates ; they break it, and strew it at their feet, whence it is lifted and disposed of to the smeltmg- houses. Inferior ores, containing a notable proportion of stony matters, are also broken with the beater, and the rich parts are separated by riddling and washing from the useless matters. The smaller ore is washed on a sieve by shaking it in a stream of water, which carries away the lighter stony pieces, and leaves the denser metalliferous. They are then sorted by hand. Thus by beating, stamping, and riddling in water, the stony substances are in a great measure separated. The finer ground matter is washed on a plane table, over which a current of water is made to flow. Finally, the ore nearly fine is put into a large tub with water, and briskly stirred about with a shovel, after which it settles in the order of richness, the pure metallic ore being nearest the bottom. The stamps used for copper ore in Cornwall are the same as those used for tin ores, of which we shall speak in treating of the latter metal, as well as of the boxes for washing the fine powder or slime. These, in fact, do not differ essentially from the stamping mills and washing apparatus described in the article Metallurgy. Crushing rolls are of late years much employed. See Lead and Tin. Cornwall being destitute of coal, the whole copper ore which this county produces is sent for smelting to South Wales. Here are 15 copper works upon the Swansea and Neath, which pursue a nearly uniform and much improved process, consisting in a series of calcinations, fusions, and roaslings, executed upon the ores and the matters resulting from them. The furnaces are of the reverberatory construction ; they vary in their dimensions and in the number of their openings, according to the operations for which they were in- tended. There are 5 of them :— 1. The calcining furnace cr calciner; 2. The melting furnace ; 3. The roasting furnace or roaster ; 4. The refining furnace ; 5. The heating or igniting furnace. 1. The calcining furnace rests upon a vault, c,dnto which the ore is raked down after being calcined; it is built of bricks, and bound with iron bars, as shown in the elevation, fig. 368. The hearth, b B,figs. 368 and 370, is placed \i\wn a level with the lower horizon- tal binding bar, and has nearly the form of an ellipse, truncated at the two extremities of its great axis. It is horizontal, bedded with fire-bricks set on edge, so that it may be re- moved and repaired without disturbing the arch upon which it reposes. Holes, not visible m the figure, are left in the shelves before each door, c c, through which the roasted ore is let fall into the subjacent vault. The dimensions of the hearth b b are immense, beinj from 17 to 19 feet in length, and from 14 to 16 in breadth. The fire-place, a. Jig. 370, is from 4i to 5 feet long, and 3 feet wide. The bridge or low wall, bjfig. 374, which sepa- rates the fire-place from the hearth, is 2 feet thick ; and in Mr. Vivian's smelting-worki is hollow, as shown in the figure, and communicates at its two ends with the atniosphere, in order to conduct a supply of fresh air to the hearth of the furnace. This judicious contrivance will be described in explaining the roasting operation. The arched roof of the furnace slopes down from the bridge to the beginning of the chimney, f,figs. 369, 870, its height above the hearth being at the first point about 26 inches, and from 8 to 12 at the second. Such great calcining furnaces have 4 or 5 doors, ccc c,fig. 370, one for the fire-place, ts shown at the right hand in fig. 369, and 3 or 4 others for working the ore np^n the COPPER. 471 ' leverberatory hearth. If there be 3, 2 of them are placed between the vertical bmding bars upon one side, and a third upon the opposite side of the furnace ; if there be 4, 2 are placed upon each side, facing one another. These openings are 12 inches square, and are bound with iron frames. The chimney is about 22 feet high, and is placed at one angle of the hearth, as at/,^g. 870, being joined by an inclined flue to the furnace. For charging it with ore there are usually placed above the upper part ol the vault ^ hoppers, E E, in a line with the doors ; they are formed of 4 plates of iron, supported m an iron frame. Beneath each of them there is an orifice for letting the ore down mto the These furnaces serve for calcining the ore, and the matts or crude coppers : for the latter purpose, indeed, furnaces of two stories are sometimes employed, as represented myig. 878. The dimensions of each floor in this case are a little less than the preceding. Two doors, c c, correspond to each hearth, and the workmen, while employed «t the upper story, stand upon a raised moveable platform. .^ t. r *i. 2. Melting furnace, figs. Zll and 372. The form of the hearth is also elliptical, but the dimensions are smaller than 871,872 in the calcining furnace. The length does not exceed 11 or 11 f feet, and the breadth varies from 7 to 8. The fire-place is however larger in proportion, its length being from 3J feet to 4, and its breadth from 3 to 3| ; this size being requisite to produce the higher temperature of this furnace. It has fewer openings, there being commonly three; one to the fire-place at i), a second one, o, in the side, kept generaUy shut, and used only when incrustations need to be scraped off the hearth, or when the furnace is to be entered for repairs; and the third or working-door, g, placed on the front of the furnace beneath the chimney. Through it the scoriae are raked out, and the melted matters are stirred and puddled, &c. The hearth is bedded with infusible sand, and slopes slightly towards the side door, to facilitate the discharge of . . the metal. Above this door there is a hole in the wall of the chimney (fig- 872) for letting the metal escape. An iron gutter, o, leads it into a pit, k, bottomed with an iron receiving-pot, which may be lifted out by a crane. The pit m is fiUed with water, and the metal becomes granulated as it falls into the receiver. me melting furnaces are surmounted by a hopper, L, as shown in ^g. 371. , . ♦• Melting furnaces are sometimes used also for calcination. There are some such near Swansea, which serve this double purpose ; they are composed of 3 floors (fig. 373.) The floor A is destined for melting the calcined ore ; the other two, B c, serve for calcination. The heat being less powerful, upon the upper sole c, the ore gets dried upon it, and begms to be calcined — a process completed on the next floor. Square holes, rf, left in the hearths B and c, put them in communication with each other, and with the lower one A ; these perforations are shut during the operation by a sheet of iron, removeable at pleasure. , . The hearths 6 and c are made of bricks; they are honzonal at top and slightly vaulted beneath : they are 2 bricks thick, and their dimensions are larger than those of the infe- rior hearths, as they extend above the fire-place. On the floors destined for calcination the furnace has two doors on one of its sides : on the lower story there are also two ; but they are differently collocated. The first, being in the front of the furnace, serves for drawin- off the scoria, for working the metal, &c. ; and the second, upon the side, admits workmen to make necessary repairs. Below this door the discharge or lap-hole a is placed, which communicates by a cast-iron gutter with a pit filled with water, ine dimensions of this furnace in length and breadth are nearly the same as those of ^he melting furnace above described; the total height is nearly 12 feet. It is charged oy means of one or two hoppers. , , ^ ,.. •„ „„„«r«l iinitlo. 3. Roasting furnace. — The furnaces employed for this purpose are m ?;n^J«' ■J***^ gous to the calling ones; but in the smelting works of Hafod, the property of M^. Vivian, these furnaces, alluded to above, present a peculiar ?o"Stniction, for the purpose of introducing a continuous current of air upon the metaU in order to 'a^.'"^^^ I^ °*^, dizemeT This process was originally invented by Mr. Sheffield, who disposed of his tMitent right to Messrs. Vivian. ^ , /. v •-».,« <«. qta aimI The aii is admitted by a channel, c c, through the middle of the fi^^;^"^^^' ■^^- ^I^'.^J^ extending all its length; it communicates with the atmosphere f-V^M ^^LJ^^f^ ^^^ •quare holes, 6 6, left at right angles to this channel, conduct the air into the m- 472 COPPER. f-, IK: n.^i ■Tiri 'I f : V ■ If - I I i ', r ' ' nacb. This very simple construction produces a powerful effect in the roasting opem- lion. It not only promotes the oxydizement of the metals, but burns the smoke, and as- sists in the vaporjzation of the sulphur ; while by keeping the bridge cool it preserves it from wasting, and secures uniformity of temperature to the hearth, 4. Refinittg furnace. — In this, as in the melting furnace, the sole slopes towardft the door in front, instead of towards the side doors, because in the refining furnace the copper collects into a cavity formed in the hearth towards the front door, from which it is lifted out by ladles ; whereas, in the melting furnaces, the metal is run out by a tap- hole in the side. The hearth sole is laid with sand ; but the roof is higher than in the melting furnace, being from 32 to 36 inches. If the top arch were too much depressed, there might be produced upon the surface of the metal a layer of oxyde very prejudicial to the quality of the copper. When the metal in that case is run out, its surface so- lidifies and cracks, while the melted copper beneath breaks through and spreads irregu- lafly over the cake. This accident, called the rising of the coppery hinders it from being laminated, and requires it to be exposed to a fresh refining process, when lead must be added to dissolve the oxyde of copper. This •'« the only occasion upon which the addi- tion of lead is proper in refining copper. When the metal to be refined is mixed with Others, particularly with tin, as in extracting copper from old bells, then very wide fur- naces must be employed, to expose the metallic bath upon a great surface, and in a thin stratum, to the oxydizing action of the air. The door g, fg. 372, upon the side of the refining furnace, is very large, and is shut with a framed brick door, balanced by a counter-weight. This door being open during the refining process, the heat is stronger at b than at K,{figs. 371,312.) 5. Heating furnaces^ being destined to heat the pigs or bars of copper to be laminated, as well as the copper sheets themselves, are made much longer in proportion to their breadth. Their hearth is horizontal, the vault not much depressed ; they have only one door, placed upon the side, but which extends nearly the whole length of the furnace ; this door may be raised by means of a counter- weight, in the same way as in the furnaces for the fabrication of sheet-iron and brass. Series of operations to which the are is svbjecttd. — The ores which are smelted in the Swansea works are cupreous pyrites, more or less mingled with gangue (vein-stone). The pyrites is composed of nearly equal proportions of sulphuret of copper and sulphuret of iron. The earthy matters which accompany the pyrites are usually silicious, though in some mines the metalliferous deposite is mixed with clay or fluate of lime. Along with these substances, pretty uniformly distributed, tin and arsenical pyrites occur occasionally with the copper ; and though these two metals are not chemically combined, yet they cannot be separated entirely in the mechanical preparations. The constituent parts of the ore prepared for smelting are, therefore, copper, iron, sulphur, with tin, arsenic, and earthy matters in some cases. The different ores are mixed in such proportions that the average metallic contents may amount to 8^ per cent. The smelting process consists in alternate roastings and fusions. The following description of it is chiefly taken from an excellent paper, published by John Vivian, Esq., in the Annals of Philo- sophy for 1823. In the roasting operation the volatile substances are disengaged mostly in the gaseons state, while the metals that possess a strong affinity for oxygen become oxydized. In the fusion the earthy substances combine with these oxydes, and form glassy scoriae or slags which float upon the surface of the melted metal. These calcinations and fusions take place in the following order : — 1. Calcination of the ore. 2. Melting of the calcined ore. 3. Calcination of the coarse metal. 4. Melting of the calcined coarse metal. 5. Calcination of the fine metal (second matt). 6. Melting of the calcined fine metal. 7. Roasting of the coarse copper. In some smelting works, this roasting is repeated four times; in which case a calcination and a melting are omitted. In the Havod works, however, the same saving is made without increasing the number of roastings. 8. Refining or toughening the copper. Besides these operations, which constitute the treatment of copper properly speaking, two others are sometimes performed, in which only the scoriae are melted. These may be designated by the letters a and 6. a is the re-melting of the portion of the scoriae of the second process, which contain some metallic granulations. 6 is a particular melt- ing of the scoriaB of the fourth operation. This fusion is intended to concentrate the X>articles of copper in the scoriae, and is not practised in all smelting works. First operation. Calcination of the ore. — The different c/es, on arriving from Corn- wall and other distiicts where they are mined, are discharged in continuous cargoes at the smelting works, in such a way, that by taking out a portion from several heaps at. n time, a tolerably uniform mixture of ores is obtained ; which is very essential in • foundry, because, the ores being different in qualities and contents, they act m COPPER. 473 fluxes upon each other. The ore thus mixed is transported to the works in wooden measures that hold a hundred-weight. The workmen intrusted with the calcination convey the ore into the hoppers of the calcining furnace, whence it falls into the hearth; other workmen spread it uniformly on the surface by iron rakes. The charge o! a fur- nace is from three tons to three tons and a half. Fire is applied and gradually increased, till, towards the end of the operation, the temperature be as high as the ore can support without melting or agglutinating. To prevent this running together, and to aid the ex- trication of the sulphur, the surfaces are renewed, by stirring up the ore at the ena oi every hour. The calcination is usually completed at the end of 12 hours, when the ore is tumbled into the arch under the sole of the furnace. Whenever the ore is cold enougH to be moved, it is taken out of the arch, and conveyed to the calcined heap. The ore in this process hardly changes weight, having gained in oxydizctnent nearly as much as it has lost in sulphur and arsenic; and if the roasting has been righUy man- aged, the ore is in a black powder, owing to the oxyde of iron present. Second operation. Fusion of the calcined ore.— The calcined ore is likewise given to the melters in measures containing a hundred weight. They toss it into hoppers, and after it has fallen on the hearth, they spread it uniformly. They then let down the door, and lute it tightly. In this fusion there are added about 2 cwt. of scoriee pro- ceeding from the melting of the calcined matt, to be afterwards described. The object of this addition is not only to extract the copper that these scoriae may contain, but especially to increase the fusibility of the mixture. Sometimes also, when the composi- tion of the ore requires it, lime, sand, or fluor spar is added; and particularly the last fluxmg article. , ^ , /. j • . i The furnace being charged, fire is applied, and the sole care of the founder is to keep up the heat so as to have a perfect fusion; the workman then opens the door, and Stirs about the liquid mass to complete the separation of the metal (or rather of the matt) from the scoriae, as well as to hinder the melted matter from sticking to the sole. The furnace being ready, that is, the fusion being perfect, the founder takes out the scoriae by the front door, by means of a rake. When the matt is thus freed from the scoriae, a second charge of calcined ore is then introduced to increase the metallic bath ; which second fusion is executed like the first. In this way, new charges of roasted ore are put in till the matt collected on the hearth rises to a level with the door-way, which happens commonly after the third charge. The tap hole is now opened; the matt flows out into the pit filled with water, where it is granulated durmg its immersion; and it collects in the pan placed at the bottom. The granulated matt is next con- veyed into the matt warehouse. The oxydation with which the grains get covered by the action of the water does not allow the proper color of the matt or coarse metal to be distinguished ; but in the bits which stick in the gutter, it is seen to be of a steel gray. Us fracture is compact, and its lustre metallic. The scoriae often contain metallic grains; they are broken and picked with care. All the portions which include some metallic particles are re-melted in an accessory process. The rejected scoria have been found to be composed of silicious matter 59, oxyde of copper 1, oxyde of In this operation, the copper is concentrated by the separation of a great part of the matters with which it was mixed or combined. The granulated matt produced, contains in eeneral 33 per cent, of copper; it is therefore four times richer than the ore; and its mass is consequently diminished in that proportion. The constituent parts are prmci- pally copper, iron, and sulphur. .,..,. , r -vi • The most important point to hit in the fusion just described, is to make a fusible mix- ture of the earths and the oxydes, so that the matt of copper may, in virtue of its greater specific gravity, fall to the under-part, and separate exactly from the slag. This point is attainetlby means of the metallic oxydes contained in the scoriae of the fourth operation, of which 2 cwt. were added to the charge. These consist almost entirely of black oxyde of iron. When the ores are very difiicult to melt, a measure of about half a hundred- weight of fluor spar is added ; but this must be done with precaution, for fear of m- creasing the scoriae too much. . v i • The business goes on day and night. Five charges are commonly put through hands in the course of 24 hours ; but when all circumstances are favorable— that is to say, when the ore is fusible, when the fuel is of the first quality, and when the furnace is in good condition, even six charges a day have been despatched. The charge is a ton and a half of calcined ore, so that a melting furnace corresponds nearly to a calcining furnace ; the latter turning out nearly 7 tons of calcined ore m Z4 hours. The workmen are paid by the ton. . «,. v- ♦ ^e ♦!.:. Third operation. Calcination of the coarse metal, or the ma//.— The object ol this operation is principally to oxydize the iron, an oxydation easier to execute than m the first 474 COPPER. II ealcininsr, because the metal is now disengaged from the earthy sobstances which screened it from the action of the air. This calcination is executed in the furnace already represented, _^g«. 296, 297 298, page 324, exactly in the same way as the ore was calcined. The metal must be perpetn! illy stirred about, to expose all its surfaces to the action of the hot air, and to hinder the clotting together. The operation lasts 24 hours; during the first six, the fire should be Very moderate, and thereafter gradually increased to the end of the calcination. The chaise is, like that of the first, 3 tons and a half. Fourth operation. Melting of the calcined coarse metal, or calcined matt. In the fusion of this first calcined matt, some scoriffi of the latter operations must be added, which are very rich in oxyde of copper, and some crusts from the hearth, which are likewise impregnated with it. The proportion of these substances varies according to the qualitj of the calcined malt. In this second fusion, the oxyde of copper contained in the scoriae is reduced by the affinity of the sulphur, one portion of which passes to the state of acid, while the other forms a subsulphurel with the copper become free. The matt commonly contains a suf- ficient quantity of sulphur to reduce the oxyde of copper completely; but if not, which may happen if the calcination of the matt has been pushed too far, a small quantity of uncalcined matt must be introduced, which, by furnishing sulphur, diminishes the ricli- ness of the scoriae, and facilitates the fusion. The scoriae are taken out by the front door, by drawing them forward with a rake. They have a great specific gravity; are brilliant with metallic lustre, very crystalline, and present, in the cavities, crystals like those of pyroxene ; they break easily into verr sharp-edged fragments. They contain no granulated metal in the interior ; but it some times occurs, on account of the small thicknesses of the stratum of scorise, that these car ry off with them, when they are withdrawn, some metallic particles. These scoriae, as we have already stated, under the fusion of the roasted ore, are ii general melted with it. In some cases, however, a special melting is assigned to them. The matt obtained in this second fusion is either run out into water like the first, or moulded into pigs (ingots), according to the mode of treatment which it is to undergo. This matt, called by the smelters yine mefal when it is granulated, and bine metal when it is in pigs, is of a light gray color, compact, and bluish at the surface. It is collected in the first form when it is to be calcined anew ; and in the second, when it must immediately undergo the operation of roa«/t?jg. Its contents in copper are 60 per cent. This operation, which is sometimes had recourse to, lasts 5 or 6 hours. The charge is 1 Ion. (6) Particular fusion of the scoria of the fourth operation. — In re-melting these scoriae the object is to procure the copper which they contain. To effect this fusion, the scorie are mixed with pulverized coal, or other carbonaceous matters. The copper and several other metals are deoxydized, and furnish a white and brittle alloy. The scoriee resulting from this taelting are in part employed in the first melting, and in part thrown away. They are crystalline, and present crystals oAen in the cavities, which appear to belong to ksilicale of iron They have a metallic lustre, and break into very sharp-edged fragments. The white metal is melted again, and then united to the product of the second fusion. Fifth operation. Calcination of the second matt, or fine metal of the smelter. — This is executed in precisely the same way as that of the first matt. It lasts 24 hours; and the charge is usually 3 tons. Sixth operation. Melting of the calcined fine metal. — ^This fusion is conducted like that of the first matt. The black copper, or coarse copper, which it produces, contains from 70 to 80 per cent, of pure metal ; it is run into ingots, in order to undergo the operation of roasting. The scoriae are rich in copper; they are added to the fusion of the calcined coarse metal of the fourth operation. In the smelting houses of Messrs. Vivian, at Hafod, near Swansea, the fifth and sixth operations have been omitted of late years. The second matt is run into pigs, under the name of blue metal, to be immediately exposed to the roasting. The disposition of the canal a a', fig. 374, which introduces a continuous current of air to the hearth of the furnace, accelerates and facilitates the calcination of the matt; an advantage which has simplified the treatment, by diminishing the number of calculations. Seventh operation. Roasting of the coarse copper, the product of the sixth operation.^ The chief object of this operation is oxydizement ; it is performed either in an ordinary roasting furnace, or in the one belonging to fig. 302, which admits a constant current of air. The pigs of metal derived from the preceding melting are exposed, on the hearth of the furnace, to the action of the air, which oxydizes the iron and other foreign metals irith which the copper is still contaminated. The duration of the roasting varies from COPPER. 475 4^ ^ J2 to 24 hours, according to the degree of purity of the crude copper. The tempertturt should le graduated, in order that the oxydizement may have time to complete, and that the volatile substances which the copper still retains may escape in the gaseous form. The fusion must take place only towards the end of the operation. The charge varies from a ton and a quarter to a ton and a half. The metal obtained i^ run out into moulds of sand. It is covered with black blisters, like steel of cementation ; whence it has got the name of blistered copper. In the interior of these pigs, the copper presents a porous texture, occasioned by the ebullition produced by the escape of the gases during the moulding. The copper being now aUnost entirely purged from the sulphur, iron, and the other substances with which it was combined, is in a fit state to be refined. This operation affords some scoriae ; they are very heavy, and contain a great deal of oxyde of copper, sometimes even metallic copper. These scoriae, as well as those of the third melting and of the refining, are added to the second fusion, as we have already stated, in describing the fourth operation. In some works, the roasting is repeated several times upon the blue metal, in order to bring it to a state fit for refining. We shall afterwards notice this modification of the treatment. Eighth operation. Refining or toughening. — The pigs of copper intended for refining are put upon the sole of the refining furnace through the door in the side. A slight heat is first given, to finish the roasting or oxydation, in case this operation has not already been pushed far enough. The fire is to be increased by slow degrees, so that, by the end of 6 hours, the copper may begin to flow. When all the metal is melted, and when the heat is considerable, the workman lifts up the door in the front, and withdraws with a rake the few scoriae which may cover the copper bath. They are red, lamellated, very heavy, and closely resemble protoxyde of copper. The refiner takes then an assay with a small ladle, and when it cools, breaks it in a vice, to see the state of the copper. From the appearance of the assay, the aspect of the bath, the state of the fire, &c., he judges if he may proceed to the toughening, and what quantity of wooden spars and wood charcoal he must add to render the metal malleable, or, in the language of the smelters, bring it to the proper pitch. When the operation of refining begins, the copper is brittle or dry, and of a deep red color approaching to purple. Its grain is coarse, open, and somewhat crystalline. To execute the refining, the surface of the metal is covered over with wood charcoal, and stirred about with a spar or rod of birch wood. The gases which escape from the wood occasion a brisk effervescence. More wood charcoal is added from time to time, so that the surface of the metal may be always covered with it, and the stirring is con- tinued with the rods, till the operation of refining be finished, a circumstance indicated by the assays taken in succession. The grain of the copper becomes finer and finer, and its color gradually brightens. When the grain is extremely fine, or closed, when the trial pieces, half cut through and then broken, present a silky fracture, and when the copper is of a fine light red, the refiner considers the operation to be completed ; but he verifies still further the purity of the copper, by trying its malleability. For this pur- pose, he takes out a sample in his small ladle, and pours it into a mould. When the copper is solidified, but still red-hot, he forges it. If it is soft under the hammer, if it does not crack on the edges, the refiner is satisfied with its ductility, and he pronounces it to be in its proper state. He orders the workmen to mould it ; who then lift the copper out of the furnace in large iron ladles lined with clay, and pour it into moulds of the size suitable to the demands of commerce. The ordinary dimensions of the ingots or pigs are 12 inches broad, 18 long, and from 2 to 2| thick. The period of the refining process is 20 hours. In the first six, the metal heats, and suffers a kind*.of roasting ; at the end of this time it melts. It takes four hours to reach the point at which the refining, properly speaking, begins ; and this last part of the process lasts about 4 hours. Finally, 6 hours are required to arrange the moulds, cast the ingots, and let the furnace cool. The charge of copper in the refining process depends upon the dimensions of the fur- nace. In the Hafod works, one of the most important in England, the charge varies from 3 to 5 tons ; and the quantity of pure copper manufactured in a week is from 40 to 50 tons. The consumption of fuel is from 15 to 18 parts of coal, for one part of refined copper in pigs. When the copper offers difiiculties in the refining, a few pounds of lead are added to it. This metal, by the facility with which it scorifies, acts as a purifier, aiding the oxydation of the iron and other metals that may be present in the copper. The lead ought to be added immediately after removing the door to skim the surface. The copper should be constantly stirred up, to expose the greatest possible surface to the action of the air, and to produce the complete oxydation of the lead ; for the smallest quantity of this metal alloyed in copper, is diflicult to clear up in the lamination; that is to say, the scale of oxyde does not come cleanly from the surface of the sheets. li If. II IK 1 J r - » 4: ? n • I i ■' ^ 476 COPPER. The operation of refining copper is delicate, and requires, npon the part of the woiiC* men, great skill and attention to give the metal its due ductility. Its surface ought to be entirely covered with wood charcoal; without this precaution, the refinii.g of the metal would go backy as the workmen say, during the long interval which elapses in the moulding ; whenever this accident happens, the metal must be stirred up anew with the wooden pole. Too long employment of the wooden rod gives birth to another remarkable accident, for the copper becomes more brittle than it was prior to the commencement of the re- fining; that is, when it was dry. Its color is now of a very brilliant yellowish red, and its fracture is fibrous. When this circumstance occurs, when the refining, as the workmen say, has gone ioofar, the refiner removes the charcoal from the top of the melted metal ; he opens the side door, to expose the copper to the action of the air, and it then resumes its malleable condition. Mr. Vivian, to whom we owe the above very graphic account of the processes, has explained, in a very happy manner, the theory of refining. He conceives, we may con- clude, that the copper in the dry state^ before the refining, is combined with a sjmiII por tion of oxygen, or, in other words, that a small portion of oxyde of copper is difi*used through the mass, or combined with it ; and that this proportion of oxygen is expelled by the deoxydizing action of the wood and charcoal, whereby the metal becomes malle- able. 2. That when the refining process is carried too far, the copper gets combined with a little charcoal. Thus copper, like iron, is brittle when combined with oxygen and charcoal ; and becomes malleable only when freed entirely from these two substances. It is remarkable, that copper, in the dry state, has a very strong action upon iron ; and that the tools employed in stirring the liquid metal become very glistening, like those used in a farrier's forge. The iron of the tools consumes more rapidly at that time, than when the copper has acquired its malleable state. The metal requires, also, when dry, more time to become solid, or to cool, than when it is refined ; a circumstance depending, probably, upon the difference in fusibility of the copper in the two states, and which seems to indicate, as in the case of iron, the presence of oxygen. When the proper refining point has been passed, another very remarkable circum- stance has been observed ; namely, that the surface of the copper oxydizes more difficultly, and that it is uncommonly brilliant ; reflecting clearly the bricks of the furnace vault. This fact is favorable to the idea suggested above, that the metal is in that case combined with a small quantity of carbon ; which absorbs the oxygen of the air, and thus protects the metal from its action. Copper is brought into the market in difierent forms, according to the purposes which it is to serve. What is to be employed in the manufacture of brass is granulated. In this condition it presents more surface to the action of zinc or calamine, and combines with it more readily.- To produce this granulation, the metal is poured into a large ladle pierced with holes, and placed above a cistern filled with water, which must be hot or cold, according to the form wished in the grains. When it is hot, round grains are obtained analogous to lead shot ; and the copper in this state is called bean shot. When the melted copper falls into cold water perpetually renewed, the granulations are irregular, thin, and ramified ; constituting /ea//ii?refll shot. The bean shot is the form em- ployed in brass making. Copper is also made into small ingots, about 6 ounces in weight. These are intended for exportation to the East Indies, and are known in commerce by the name of Japan copper. Whenever these little pieces are solidified, they are thrown, while hot, into cold water. This immersion slightly oxydizes the surface of the copper, and gives it a fine red color. Lastly, the copper is often reduced into sheets, for the sheathing of ships, and many other purposes. The Hafod works possess a powerful rolling mill, composed of four pair? of cylinders. It is moved by a steam engine, whose cylinder has 40 inches diamete:. See the representation of the rolling mill of the Royal Mint, under Gold. The cylinders for rolling copper into sheets are usually 3 feet long, and 15 inches in diameter. They are uniform. The upper roller may be approached to the under one, by a screw, so that the cylinders are brought closer, as the sheet is to be made thinner. The ingots of copper are laid upon the sole of a reverberatory furnace to be heated ; they are placed alongside each other, and they are formed into piles in a cross-like ar- rangement, so that the hot air may pass freely round them all. The door of the furnace is shut, and the workman looks in through a peep-hole from time to time, to see if they have taken the requisite temperature ; namely, a dull red. The copper is now passed between the cylinders ; but although this metal be very malleable, the ingots cannot be reduced to sheets without being several times heated ; because the copper cools, and ae quires, by compression, a texture which stops the progress of the lamination. These successive heatings are given in the furnace indicated above ; though, when the i COPPER. 477 sheets are to have a very great size, furnaces somewhat dififerent are had recourse to. They are from 12 to 15 feet long, and 5 wide. See Brass. , . ^ r a The copper, by successive heating and lamination, gets covered with a co&i o! oxy^le^ which is removed by steeping the sheets for a few days in a pit filled with urine ; they are then put upon the sole of the heating furnace. Ammonia is formed, which acts on the copper oxyde, and lays bare the metallic surface. The sheets are next rubbed with a piece of wood, then plunged, whUe still hot, into water, to make the oxyde scale olT; vid lastly, they are passed cold through the rolling press to smooth them. They are now tat square, and packed up for home sale or exportation. ,„,.,« ♦ r The following estimate has been given by MM. Dufrenoy and Elie de Beaumont of tte expense of manufacturing a ton of copper in South Wales. 12| tons of ore, yielding 8| per cent, of copper 55 20 tons of coals - - - - 8 Workmen's wages, rent, repairs, &c. - - 13 d. 76 The exhalations from the copper smelting works are very detrimental to both vegetaMe and animal life. They consist of sulphurous acid, sulphuric acid, arsenic, and arsenious acids various gases and fluoric vapors, with solid particles mechanically swept away into the wr, besides the coal smoke. Mr. Vivian has invented a very ingenious method of passing the exhalations from the calcining ores and malts along horizontal flues, or rather galleries of great dimensions, with many crossings and windings of the current, and ex- posure during the greater part of the circuit to copious showers of cold water. By this simple and powerful system of condensation, the arsenic is deposited in the bottoms of the flues, the sulphurous acid is in a great measure absorbed, and the nuisance is re- markably abated. ^ . ^ ^ ... . The following figures represent certain modifications of the copper calcining and smelting copper furnaces of Swansea. ^ ^^^ .x. j i Fig. 376, is the section of the roasting furnace lengthwise; fig. 375, the ground plan; in which a is the fire-door; b the grate; c the fore-bridge; d the chimney; ee working 375 377 apertures on each of the long sides of the furnace, through which the ore is in- troduced, spread, and turned over ; // cast-iron hoppers ; gg openings in the vaulted roof; h the hearth-sole ; i i holes in this ; fe a vaulted space under the hearth. The hearth has a suitable oval shape, and is covered with a flat arch. Its length is 16 feet, breadth 13j^, mean ***JFi> 37? U a longitudinal section of the melting furnace ; fig. 378, the ground plan, in whk a'is the fire door ; b the grate ; c the fire biidge j d the chimney ;e the side openings;/ the working doors; g the raking-out hole; h iron spouts, which conduct the melted metal into pits filled with water. ., ,, i The melting furnace is altogether smaller ; but its firing hearth is considerably largef 478 COPPER. than in the roasting fbrnace. The long axis of the oval hearth is 14 feet ; its short JO feet ; its mean height 2 feet. 878 The principal ore smelted at Chessy is the azure copper, which was discovered by accident in 1812. Red copper ore, also^ has come into operation there since 1825. The average metallic contents of the richest azure ore are from 33 to 36 per cent. ; of the poorer, from 20 to 24. The red ore contains from 40 to 67 parts in 100. The ore is sorted, so that the mean contents of metal may be 27 per cent., to which 20 per cent, of limestone are added • whence the cinder will amount to 60 per xent. of the ore. A few per cents, of red copper slag, with some quicklime and gahrslag, are added to each charge, which consists of 200 pounds of the above mixture, and ,, . , ^50 pounds of coke. When the furnace {fourneau a mancfu, see the Scotch smelting hearth, under Lead) is in good action, from 10 to 14 such charges are worked in 12 hours. When the crucible is fuU of metal at the end of this period, during which the cinder has been frequently raked off, the blast is stopped, and the matte floating over the metal being sprinkled with water and taken off, leaves the black copper to be treated in a similar way, and converted into roHttts. The refinmg of this black copper is performed in a kind of reverberatory furnace. The cinders produced in this reduction process are either vitreous and light blue, which are most abundant ; cellular, black, imperfectly fused from excess of lime ; or, lastly, red, dense, blistery, from defect of lime, from too much heat, and the passage of proloxyde mto the cinders. They consist of silicate of alumina, of lime, protoxyde of iron ; the red contain some silicate of copper. The copper-refining fur- nace at Chessy, near Ly- ons, is of the kind called Spleiss-o/en (split hearths) by the Germans. Fig. 307 is a section lengthwise ia the dotted line a b of Jig, 380, which is the ground plan. The foundation-walls are made of gneiss; the arch, the fire-bridge, and the chimney, of fire-bricks. The hearth, a, is formed of a dense mixture of coal-dust, upon a bottom of well-beat clay, 6, which reposes upon a bed of brickwork c. Be« neath this there is a slag bottom d; e is the upper, and / the under discharge hole. The hearth is egg. shaped ; the longer axis be- ing 8 feet, the shorter 6| . , J J r • L J ..,. .^ , ^^^» '" ^^« middle it is 10 inch^ deep, and furnished with the outlets g g, which lead to each of the Spleus-hearth* h h,fig, 380. These ouUets are contracted with fire-bricks » t, till the proper period of the discharge. The two hearths are placed in communication by a canal k : they are 3* feet m diameter, 16 inches deep ; are floored with weU-beat coal ashes, and receive about 27 cwt. for a charge. lis the grate; m, the fire-bridge; n, the boshes in which the tuyeres lie; o, the chimney; p, the working door through which the slags may be drawn off. Above this is a small chimney, to carry off the flame and smoke whenever the door ii opened. The smelting post or charge, to be purified at once, consists of 60 cwt. of black copper, to which a little granular copper and copper of cementation is added j the COPPER. 479 sumption of pit-coal amounts to 36 cwt. As soon as the copper is melted, tht Wilows are set a-going, and the surface of the metal gets soon covered with • 380 moderately thick layer of cinder, which is drawn off. This is the first skimming or decrassage. By and by, a second layer of cinder forms, which is in like manner removed ; and this skimming is repeated, to allow the blast to act upon fresh metallic surfaces. After 4 or 5 hours, no more slag appears, and then the fire is increased. The melted mass now begins to boil or work {travaiUer), and continues so to do, for about f of an hour, or an hour, after which the motion ceases, though the fire be kepC up. The gahrproof is now taken ; but the metal is seldom fine in less than | of aq hour after the boil is over. Whenever the metal is run off by the tap-hole into the two basins i t, called split-hearths, a reddish vapor or mist rises from its surface, composed of an infinite number of minute globules, which revolve with astonishing velocity upon their axes, constituting what the Germans called spratzen (crackling) of the copper. They are composed of a nucleus of metal, covered with a film of protoxyde, and are used as sand for strewing upon manuscript. The copper is separated, as usual, by sprinkling water upon the surface of the melted metal, in the state of rosettes, which are immediately immersed in a stream of water. This refining process lasts about 16 or 17 hours ; the skimmings weigh about 50 cwt. ; the refuse is from 15 to 17 per cent. ; the loss from 2 to 3 per cent. The gahrslag amounts to 11 cwt. The refining of the eliquated copper (called darrlinge) from which the silver has been sweated out by the intervention of lead, can be performed only in small hearths. The ibilowing is the representation of such a furnace, called, in German, Kupfergahrheerd, Fig, 381 is the section lengthwise ; Jig. 382 is the section across ; and Jig, 383 is the 381 383 1 frmind plan, in which a is the hearth-hollow; b, a massive wall; c, the mass out cf Irtldi the hearth is formed; d, cast-iron plates covering the hearth; e, opening fjt 480 COPPER. COPPER. 481 I njnning otf the liquid slag; /, a small waU; g, iron curb for keeping the eoidi The hearth being heated with a bed of charcoal, { cwt. of darrlinge are laid over it, and covered with more fuel : whenever this charge is melted, another layer of the coaJ and darrlinge is introduced, and thus in succession till the hearth become full or contain from 2^ to 2J cwt. In Neustadt 7^ cwt. of darrlinge have been refined in one furnace, from which 5 cwt. of gahrcopper has been obtained. The blast oxydizes the foreign metal?, namely, the lead, nickel, cobalt, and iron, with a little copper, forming the gahrslag ; which is, at first, rich in lead oxyde, and poor in copper oxyde ; but at the end, this order is reversed. The slag, at first blackish, assumes progressively a copper red tint. The slag flows off spontaneously along the channel «, from the surface of the hearth. The gahre is tested by means of a proof-rod of iron, called gahr-eisen. thrust though the luylre into the melted copper, then drawn out and plunged in cold water. As soon as the gahrspan (scale of copper) appears brownish red on the outside, and copper red within, so thin that it seems like a net-vork, and so deficient in tenacity that It cannot be bent without breaking, the refining is finished. The blast is then stopped ; the coals covering the surface, as also the cinders, must be raked oflf the copper, alter bemg left to cool a little; the surface is now cooled by sprinkling water upon it, and the thick cake of congealed metal (rondelle) is lifted off with longs, a process called •chUissen (shcmg), or sheibenreissen (shaving), which is continued till the last convex cake at the bottom of the furnace, styled the kingspiece, is withdrawn. These rondelles are immediately immersed in cold water, to prevent the oxydation of the copper ; whereupon the metal becomes of a cochineal red color, and gets covered with a thin film of protoxyde. Its under surface is studded over with points and hooks, the result of tearing the congealed disc from the liquid metal. Such cakes are called rosette copper. When the metal is very pure and free from protoxyde, these cakes may be obtained very thin, one 24th of an inch for example. The refining of two cwts. and a half of darrlinge takes three quarters of an hour, and yields one cwt. and a half of gahrcopper in 36 rosettes, as also some gahrslag. Gahr- copper generally contains from IJ to 2| per cent, of lead, along with a little nickel, silver, iron, and aluminum. Smelting of the Mann^feld copper schist^ or bituminous Mergelachiefer.— The cupreous ore is first roasted in large heaps, of 2000 cwts., interstratified with brush-wood and with some slates rich in bituminous matter, mixed with the others. These heaps arc 3 ells high, and go on burning 15 weeks in fair and 20 in rainy weather. The bitumen IS decomposed ; the sulphur is dissipated chiefly in the form of sulphurous acid ; the metal gets partially oxydized, particularly the iron, which is a very desirable circumstance towards the production of a good smelting slag. The calcined ore is diminished one tenth in bulk, and one eighth in weight ; becoming of a friable texture and a dirty yellow gray color. The smelting furnaces are cupolas (schachtofen) , 14 to 18 feet high; the fuel is partly wood charcoal, partly coke from the Berlin gas-works, and Silesia. 'The blast is given by cylinder bellows, recently substituted for the old barbarous Blasebdleen or wooden bellows of the household form. The cupreous slate is sorted, according to its composition, into slate of lime, clay, iron, &c., by a mixture of which the smelting is facilitated. For example, 1 post or charge may consist of 20 cwt. of the ferruginous slate, 14 of the calcareous, 6 of the argillaceous, with 3 of fluor spar, 3 of rich copper slags, and other refuse matters. The nozzle at the tuylre is lengthened 6 or 8 inches, to place the melting heat near the centre of the furnace. In 15 hours 1 fodder of 48 cwts. of the above mixture may be smelted, whereby 4 to 5 cwts. of maiie (crude copper, called Kupferstein in Germany) and a laije body of slags are obtained. The matte contains from 30 to 40 per cent, of copper and from 2 to 4 lo/hs (1 to 2 oz. ) of silver. The slags contain at times one tenth theii weight of copper. The rnatte is composed of the sulphurets of copper, iron, silver, zinc, along with some arsenical cobalt and nickei. The slaty slag is raked off the surface of the melted mattt from time to time. The former is either after being roasted six successive times, smelted into black copper; or it is subje^'ted to the following concentration process. It IS broken to pieces, roasted by brushwood and coals three several tunes in brick-walled kilns, containing 60 cwts., and turned over aAer every calcination ; a process of four weeks' duration. The ihrice roasted mass, called spurrost, being melted in the cupola fig' 385, with ore-cinder, yields the spurstein, or concentrated matte. From 30 to 40 cwts. of spurrost are smelted in 24 hours ; and from 48 to 60 per cent, of spurstein are obtained, the slag from the slate smelting being employed as a flux. The spurstein contains from 60 to 60 per cent, of copper, combined with the sulphurets of copper, of iron, and The spurstein is now mixed with dunnstein (a sulphuret of copper and iron produced in the original smeltings) roasted six successive times, in the quantity of 60 cwts., with ) hrushwood and charcoal; a process which requires from 7 to 8 weeks. The product of this six-fold calcination is the Gahrrost of the Germans (done and purified) ; it has a color like red copper ore, varying from blue gray into cochineal red ; a granular frac- ture; it contains a little of the metal, and may be immediately reduced into metallic copper, called kupfermachen. But before smelling the mass, it is lixiviated with water, to extract from it the soluble sulphate, which is concentrated in lead pans, and crys- tallized. The lixiviated gahroste mixed with from * to 1 of the lixiviated dunnsteinrost, and ^ to ^ of the copper slate slag, are smelted with charcoal or coke fuel in the course of 24 hours, in a mass of 60 or 80 cwts. The product is black copper, to the amount of about J the weight, and i of dunnstein or thin matte. This black copper contains in the cwt. from 12 to 20 loths (6 to 10 oz.) of silver. The dunnstein consists of from 60 to 70 per cent, of copper combined with sulphur, sulphuret of iron, and arsenic; and when thrice roasted, yields a portion of metal. The black copper lies undermost in the crucible of the furnace ; above it is the dilnn^teinf covered with the stone slag, or copper cinder, resulting from the slate-smelling. The slags being raked off, and the crucible sufficiently full, the eye or nozzle hole is shut, the dunnstein removed by cooling the surface and breaking the crust, which is about \\o\ inch thick. The same method is adopted for taking out the black copper in successive layers. For the de-silvering of this and similar black coppers, see Silver. 384 Fig, 384 is a vertical section through the form or tuyere in the dotted line a b of yig. 386. Fig. 385 is a vertical section in the dotted line c d of^g. 387. a is the shaft of the furnace, b the rest, c c the forms ; d the sole or hearth-stone, which has a slope of 3 inches towards the front wall ; € e, &c. casing walls of fire bricks ; //, &c. filling up walls built of rubbish stones \ g g ^ mass through which the heat is slowly conducted ; h h the two holes through one or other of which alternately the product of the smelting process is run off into the fore-hearth. Beneatk the hearth-sole there is a soW body of loam ; and the fore- hearth is formed with a mixture of coal-dust and clay ; k is the discharge outlet. Fig. 386 is a horizontal section of the furnace through the hole or eye in the dotted line e f oTJig. 384 ; fig. 387, a horizontal section of the shaft of the furnace through the form in the doited line g h of figs. 384 and 385. The height of the shaft, from the line E F to the top, is 14 feet ; from e to g, 25 inches ; from c to the line below 6, 2 feet ; from that line to the line opposite g g, 2 feet. The width at the line g g is 3 feet 3 inchcb, and at c 26 inches. The basins i i,fig. 386, are 3 feet diameter, and 20 inches deep. The refining of copper is said to be well executed at Seville, in Spain ; and, therefore, some account of the mode of operating there may be acceptable to the reader. The first object is to evaporate in a reverberatory furnace all the volatile substantes, such as sulphur, arsenic, antimony, &c., which may be associated with the sulphur; ani the second, to ox}'dize and to convert into scoriae the fixed substances, such as iron, lead, &c., with the least possible expense and waste. The minute quantities of gold and sil- ver which resist oxydation cannot be in any way injurious to the copper. The hearth is usually made of a refractory sand and clay with ground charcoal, each mixed in equal volumes, and worked up into a doughy consistence with water. This composition is beat firmly into the furnace bottom. But a quartzose hearth is found to answer better, and to be far more durable ; such as a bed of fire-sandstone. Before kindling the furnace, its inner surface is smeared over with a cream-con- sistenced mixture of fire-clay and water. The cast pigs, or blocks of black or crude copper, are piled upon the hearth, each suc- cessive layer crossing at right angles the layer beneath it, in order that the flame maj 31 f 462 COPPFJL COFFiiK. 483 The weight of the charge should be proportional to the capacity of the furnace »n3 such that the level of the metallic bath may be about an inch alLve the nozzle of the bellows ; for, were it higher, it would obstruct its operation, and were it too low the stream of air wo.ild strike but imperfectly the surface of the metal, and would fail to ^nl^/in ' T.'i r'^'"^ *' }?'-' ^''' 7^"^"^ P'°"''' ^y **^*^i»S »»»« oxydation and vola^ liiization of the foreign metals incomplete. the^U'o'f rwi^d/rr^d!'" ''' '"^'''' ''^^ ""'' '"^"^ ^^^^^^ ^^ ^"^ ^«^"« ^-^ 'o wf^lLm"nl«I;''^ copper is melted, charcoal is to be kindled in three iron basins lined Tnlr T^^l • ^ alongside the furnace, to prepare them for receiving their charge o? copper, whirh is to be converted in them, into rosettes. ^ IS ^coS-'^^L^tn ^l^?K^'^rr -.f'"^^^^ "'^•"^'•^l substances IS so cojMou., as to give the bath a boiling appearance ; some drops rise up to the roof giobule*. This phenomenon proves that the process is Roing on well ; and when it ceases, the operatujn is nearly completed. A small proof of cSpp^r, of he fo'rm of a end ofa polished iron roa, previously heated. This rod is dipped two or three inXS into the bath, then withdrawn and immersed in cold water. ThVcopper ?ap is detaclel n?sT (^loHnTtr' h' ^'^.""''r f " '"T" ' '^"^ ^ ^^'^'-' hfoZ.TLl Us thick- ness, color, and polish, as to the degree of purity which the coDoer has acnnirprf S.it AtThe7nforar„'t"n I' '^^""r f'- ''' T^^ ^^"^ above sHrrof,t?cr:^';o ^ tJ.h\ o^ about 11 hours of finng, the numerous small holes otiervable in the first «.cr/cA samples begin to disappear; the outer surface passes from a bright red to adark^ hue the. nner one becomes of a more uniform color, and always Jess"' and lei markS with ye lowish spots It will have acquired the greatest pitch of purity that the ZcSs can bestow, when the watches become of a dark crimson color ^ ^^^ ino nn°!''f ^^ ^*^^n ^"^ '^''P ^^'l ^^^'"'''^ P'^^*^^^^ «^ ^^^ P'-oper time; for, by prolon- ing It unduly a small quantity of cupreous oxyde would be formed, which findin- no oFSnatLl"' ''' ""'' ""'" ''^ "'"^^^ ^'y ^'^°PP^^ *>-^' br7ttTe, and'ntye mnTI't ^^?'"%™"st "ow be emptied of their burning charcoal, the opening of the tuyere Shi • ^ °^^'^',^"d;»^«. ?^''«d copper allowed to flow into Ihem through The tarSe which IS then closed w.th loam. Whenever the surface is covered with a solid cr^sTiJ L^f^Z^ Z'i^ r-"'' ^"^ ?' ^°^" ^' '^^ ^"-"^^ '^ «»^«t ]i inch thick it is rated upon hooks above the bas.n, to drain off any drops, and then carried away from the furnaT If these cakes, or rosettes, be suddenly cooled by plunging them immedktely in watS* they will assume a fine red color, from the formation of a film of oxTe ^ ' sumjt 'on'o'fXVt^^^^^^^^^^^^ '' '^^^^ ^ A ^^ o^-pper, with the con- it into wt'j^r ^Ith^ '^^^"^ ^^^^ ^?^ ^^PP^" *^^* ''^ "^^^"^ ^ «" solidified before plunging i iJln ' ^fherwise a very dangerous explosion might ensue, in consequence of hi ^t V'TT'''''.''^ °*y^^'' ^"^"^ ^^^ ^'^^'^ ^^'al, in the act of condensation On he other hand, the cake should not be allowed to cool too long in the aiV, kst it L neroxv Se^S^Stox^dr wh"'h'"' ''''}''T '".^ ^^' P"^P^^' -^ yell'; shLdS duf toTfi^' oi uie piotoxyde, which manv dealers admire. they (S^casion^'tL'^n ' ""^ ^"'^7"^- '"'* ^^^^^ ^^ ^«PP^ "« *^«'"^''»^ ^'^^ copper, fa harTb me vplK- r"wt''^ micaceous scales in the fractured faces. Such meta defects ^renol^ow't/''^'"*- ^"^ '^" ^t ""^'^" ^«"'"»^^ "«^ wire-drawn. These .Snvln thpZ«J%Ih-\''-"''' ^'.'^'' ^"'""^'^^ imagined; but, most probably, to According to M. Frerejean, proprietor of the great copper works of Vienne in Dauphiny, too low a temperature, or too much chlrcoal, gi'JS trthe metalTcub.>^ structure, or that of divergent rays; in either of which iTteT it wants tenLV'^^ lre^lTlr;:e^^"^rs^:^^ these three states in the space of ten minutes ^uccess^veiy mrougn wh^^' f L?tJ T nf th* ''"^''l"^ '^''^'^f coppe; pyrites in the Lower Hartz, near Goslar, nr^!Z^.T I'' A ^iP*""' '% collected. It is a vertical section of a truncated 2, thT^e a Z ^^" ^"^"'^ ^^''' '' "^"^^"^ *' '^' ^^ ^^'^' Py '«°»W c, a wooden chimney which stands in the centre of the mound with a small pile ci charcoal at itj? bottom, c; d d are large lumps of ore surrounded by smaller pieces; // are rubbish and earth to form a covering A current of air is admitted under the billets by an opening in the middle of each of the four sides of the base a a, so that two principal currents of air cross under the vertical axis c of the truncated pyramid, as indicated in the figure. The fire is applied through the chimney c ; the ciiarcoal at its bottom c, and the piles a a are kindled. The sulphureous ores, d /, are raised to such a high temperature as to expel the sulphur in the state of vapor. In the Lower Hartz a roasting mound continues burning during four months. Some days after it is kindled the sulphur begins to exhale, and is condensed by the air at the upper surface of the pyramid. When this seems impregnated with it, small basins 1 1 are excavated, in which some liquid sulphur collects; it is removed from lime to time with iron ladles, and thrown into water, where it solidifies. It is then refined and cast into roll brimstone. A similar roasting mound contains, in the Lower Hartz, from 100 to liO tons of ore and 730 cubic feet of wood. It yields in four months about one ton and a half of sulphur from copper pyrites. Lead ore is treated in the same way, but it furnishes less sulphur. There are usually from 12 to 15 roasting heaps in action at once for three smelting works of the Lower Hartz. After the first roasting two heaps are united to form a third, which is calcined anew, but under a shed; the ores are then stirred up and roasted for the third time, whence a crude mixture is procured for the smelting-house. The most favorable seasons for roasting in the open air are spring and autumn ; the best weather is a light wind accompanied with gentle rain. When the wind or rain obstructs the operation, this inconvenience is remedied by planks distributed round the upper surface of the truncated pyramid over the sulphur basins. Manufacturing assays of copper. — The first thing is to make such a sample as will represent the whole mass to be valued ; with which view, fragments must be taken from different spots, mixed, weighed, and ground together. A portion of this mixture being tried by the blow-pipe, will show, by the garlic or sulphurous smell of its fumes, whether arsenic, sulphur, or both, be the mineralizers. In the latter case, which often occurs, 100 gr. or 1000 gr. of the ore are to be mixed with one half its weight of saw-dust, then imbued with oil, and heated moderately in a crucible till all the arsenical fumes be dissipated. The residuum, being cooled and triturated, is to be exposed in a shallow earthen cup to a slow roasting heat, till the sulphur and charcoal be burned away. What remains, being ground and mixed with half its weight of calcined borax, one twelfth its weight of lamp black, next made into a dough with a few drops of oil, is to be pressed down into a crucible, which is to be covered with a luted lid, and to be subjected, in a powerful air furnace, first to a dull red heat, and then to vivid ignition for 20 minutes. On cooling and breaking the crucible, a button of metallic copper will be obtained. Its color and malleability indicate pretly well the quality, as does its weight the relative value of the ore. It should be cupelled with lead, to ascertain if it contains silver or gold. See Assay, and Silver. If the blow-pipe trial showed no arsenic, the first calcination may be omitted ; apff if neither sulphur nor arsenic, a portion of the ground ore should be dried, and treated directly with borax, lamp-black, and oil. It is very common to n ake a urv assay of copper ores, by one roasting and one fusion along with 3 parts of black fl'i\ : Irom m*. weight of the metallic button the richness of the ore is inferred. The humid assay is more exact, but it requires more skill and time. The sulphur and the silica are easily got rid of by the acids, which do not dissolve them, but only the metallic oxydes and the other earths. These oxydes may then be thrown down by their appropriate reagents, the copper being precipitated in the state of cither the black oxyde or jmre metal. 105 parts of black oxyde represent ICO of copper. Before entering upon the complete analysis of an ore, preliminary trials should be made, to ascertain what are its chief constituents. If it be sulphuret of copper, or coppei pyrites, without silver or lead, 100 grains exactly of its average powder may be weighed out, treated in a matrass with boiling muriatic acid for some time, gradually adding a few drops of nitric acid, till all action ceases, or tiU the ore be all dissolved. The insoluble matter found floating in the liquid contains most of the sulphur; it may be separated upon a filter, washed, dried, and weighed ; then verified by burning away. The incom- bustible residuum, treated by muriatic acid, may leave an insoluble deposite, which is to be added to the former. To the whole of the filtered solutions carbonate of potash if I'* f- ' 484 COPPER. to be added ; and the resulting precipitate, being washed, and digested repeatedly in wa« ter of ammonia, all its cupric oxyde will have been dissolved, whenever the ammonia i$ ro longer rendered blue. Caustic potash, boiled with the ammoniacal solution, will separate the copper in the state of black oxyde ; which is to be thrown upon a filter, washed, dried, and wei?hed. The matter lefk undissolved by the ammonia, consists of oxyde of iron, with probably a little alumina. The latter being separated by caustic potash, the iron oxyde maybe also washed, dried, and weighed. The powder which originally resisted the muriatic acid, is silica. jSssay of copper ores, which contain iron^ sulphur, silver, had, and antimony, 100 grains of these ores, previously sampled, and pulverized, are to be boiled with nitric acid, adding fresh portions of it from lime to time, till no more of the matter be dissolved. The whole liquors which have been successively digested and decanted uff. are to be filtered and treated with common salt, to precipitate the silver in the state of a chloride. The nitric acid, by its reaction upon the sulphur, having generated sulphuric acid, this will combme with the lead oxydized at the same time, constituting insoluble sulphate of lead, which will remain mixed with the gangue. Should a little nitrate of lead remain in the liquid, it may be thrown down by sulphate of soda, after the silver has been sepa- rated. The dilute liquid, being concentrated by evaporation, is to be mixed with ammo- nia m such excess as to dissolve all the cupric oxyde, while it throws down all the oxyde of iron and alumina ; which two may be separated, as usual, by a little caustic pot- ash. The portion of ore insoluble in the nitric acid being digested in muriatic acid, everything will be dissolved except the sulphur and silica. These being collected upon a filter, and dried, the sulphur may be burned away, whereby the proportion of each is determined. Ores of the oxyde of copper are easily analyzed by solution in nitric acid, the addition of ammonia, to separate the other metals, and precipitation by potash. The native car- bonate is analyzed by calcining 100 grains ; when the loss of weight will show the amount of water and carbonic acid ; then that of the latter may be found, by expelling it from another 100 grains, by digestion in a given weight of sulphuric acid. The copper IS finally obtained in a metaUic state by plunging bars of zinc into the solution of the sulphate. The native arseniates of copper are analyzed by drying them first at a moderate heat; after which they are to be dissolved in nitric acil. To this solution, one of nitrate of lead is to be added, as long as it occasions a precipitate ; the deposite is to be drained up- on a filter, and the clear liquid which passes through, being evaporated nearly to drvness IS to be digested in hot alcohol, which will dissolve everything except a little arseniateof lead. This being added to 'lie arseniate first obtained, from the weight of the whole, the arsenic acid, constituting 35 per cent., is directly inferred. The alcoholic solution bein" now evaporated to dryness, the residue is to be digested in water of ammonia, when the cupric oxyde will be dissolved, and the oxyde of iron will remain. The copper is procured, m the state of black oxyde, by boiling the filtered ammoniacal solution with the proper quantity of potash. The analysis of muriate of copper— atacamite— is an easy process. The ore being dissolved in nitric acid, a solution of nitrate silver is added, and from the weight of the chloride precipitated, the equivalent amount of muriate or chloride of copper is given ; for 100 of chloride of silver represent 93 of chloride of copper, and 43-8 of its metallic basis. I his calculation may be verified by precipitating the copper of the muriate from its solu- tion in dilute sulphuric acid, by plates of zinc. The phosphate of copper may be analyzed either by solution in nitric acid, and precipi- tation by potash ; or by precipitating the phosphoric acid present, by means of acetate of lead. Ihe phosphate of lead thus obtained, after being washed, is to be decomposed by dilute sulphuric acid. The insoluble sulphate of lead, being washed, dried, and weighed, indicates by Its equivalent the proportion of phosphate of lead, as also of phosphate of copper; lor 100 of sulphate of lead correspond to 92-25 phosphate of lead, and 89-5 pho»- phate of copper ; and this again to 52-7 of the black oxyde. Copper forms the ba-is of a greater number of important' alloys than any other metal. With zmc. It forms Brass m all its varieties; which see. Bronze and Bell Metal are alloys of copper and tin. This compound is prepared in crucibles when only small quantities are required ; but in reverberatory hearths, when statues, bells, or cannons are to be cast. The metals must be protected as much as pos- sible during their combination from contact of air by a layer of pounded charcoal, other- 'Vise two evils would result, waste of the copper by combustion, and a rapid oxydizement «f the tin, so as to change the proportions and alter the properties of the alloy. The fused materials ought to be well mixed by stirring, to give uniformity to the compound. See OAONZE. rii_, COPPER. r i 485 An ailoy of 100 of copper and 4*17 of tin hag been proposed by M. Cftaudei for ihz ready manutaciure of medals. After melting this aUoy, he casts it in moulds made of such bone-ash as is used for cupels. The medals are afterward subjected to the action of the .^oining press, not for striking them, for the mould furnishes perfect impressions, but for linishing and polishing them. By a recent analysis of M. Berthier, the bells of the penduks, or ornamental clocks, made in Paris, are found to be composed— of copper 72-00, tin 26-56, iron 1*44, in 100 parts. An alloy of 100 of copper and 14 of tin is said by M. Dussaussy to furnish tools, which, hardened and sharpened in the manner of the ancients, aflx)rd an edge nearly equal to that of steel. Cymbals, gongs, and the tamtam of the Chinese are made of an alloy of 100 of copper with about 25 of tin. To give this compound the sonorous propertv in the highest de- gree, it must be subjected to sudden refrigeration. M. D'Arcet, to whom this di«:coverT IS due, recommends to ignite the piece after it is cast, and to plunge it immediately into cold water. The sudden cooling Rives the particles of the alloy such a disposition, that, with a regulated pressure by skilful hammerins, they may be made to slide over each other, and remain permanently in their new position. When by this means the instru- ment has received its intended form, it is to be heated and allowed to cool slowly in the air. The particles now take a different arrangement from what they would have done by sudden refrigeration ; for instead of being ductile, they possess such an elasticity, that on being displaced by a slight compression, they return to their primary position after a series of extremely rapid vibrations ; whence a very powerful sound is emitted Bronze, bell-metal, and probably all the other alloys of tin with copper, present the same The alloy of 100 of copper with from 60 to 33 of tin forms common bell-metal It is yellowish or whitish gray, brittle, and sonorous, but not so much so as the preceding' The metal of house-clock bells contains a little more tin than that of church-bells and the bell of a repeater contains a little zinc in addition to the other ingredients ' The bronze-founder should study to obtain a rapid fusion, in order to avoid the causes of waste indicated above. Reverberatory furnaces have been long adopted for this oDera- ' L" u^T"l^nT' *5^ elliptical are the best. The furnaces with spheroidal domes are used by the bell-founders, because their alloy being more fusible, a more moderate melUng heat is required ; however, as the rapidity of the process is always a matter of consequence, they also would find advantage in employing the elliptical hearths (see th* form of the melting furnace, as figured under Smelting of copper ores.) Coal is now universally preferred for fuel. o ., ^x- / » « uuw 1 J^'^t^^.f ^^ o^.coPPer with 50 of tin, or more exacUy of 32 of the former with 14t of the latter, constitutes speculum metal, for making mirrors of reflecting tele^cooes. This compound IS near y white, very brittle, and susceptible of a fine polish with ^a bril- liant surface. The following compound is much esteemed in France for makin<' snecula. Melt 2 parts of pure copper and 1 of grain-tin in separate crucibles, incorporate thor- oughly with a wooden spatula, and then run the metal into moulds. The lower surfac«» IS the one that should be worked into a mirror. sunace Mr. Edwards, in the Nautical Almanack for 1787, gave the following instructions for making speculum metal. The quality of the copper is to be tried by making a series of alloys with tin in the nro. portion of 100 of the former to 47, to 48, to 49, and to 50 of the'latter met'al ; whe^n^ the proportions of the whitest compound may be ascertained. Beyond the last proportion the alloy begins to ose in brilliancy of fracture, and to take a bluish tint. Haviticr deter-' mined this point, take 32 parts of the copper, melt, and add one part of brass and as much silver, covering the surface of the mixture with a little black flux; when the whole is melted, stir with a wooden rod, and pour in from *15 to 16 parts of melted tin Cas indir. ted by the preparatory trials), stir the mixture again, and immediately pour it out into cold water. Then melt again at the lowest heat, adding for every 16 parts of the com- pound 1 part of white arsenic, wrapped in paper, so that it may be thrust down to the bottom of the crucible. Stir with a wooden rod as long as arsenical fumes rise and then pour It into a sand mould. While still red hot, lay themetal in a pot-full of ve^r hot e " bers, that it may cool very slowly, whereby the danger of its cracking or flying into splinters is prevented. ° "J'"s *"*" Having described the different alloys of copper and tin, I shall now treat of the method of separating these metals from each other as they exist in old cannons, damaged bells, &c. The process employed on a very great scale in France, during the Revolution, fS obtaining copper from bells, was contrived by Fourcroy ; founded upon the chemical fad that tin IS more fusible and oxydizable than copper. 1. A certain quantity of bell metal was completely oxydized by calcination '» a rrver beratory furnace ; the oxyde was raked out, and reduced to a fine powder. 2. Into the same furnace a fresh quantity of the same metal was introdueed • it wa« I r f; f .- 1,1 {C 486 COPPER. laelled, and there was added to it one half of its weiarht of the oxvde formed *« the first operation. The temperature was increased, and the mixture well incorporated ; at the <»nd of a few hours, there was obtained on the one hand copper almost pure, which sub- sided in a liquid state, and spread itself upon the sole of the hearth, while a compound of oxyde of tin, oxyde of copper, with some of the earthy matters of the furnace, collected on the surface of the metallic bath in a pasty form. These scoriae were removed with a rake, and as soon as the surface of the melted copper was laid bare, it was run out. The scoriae were levigated, and the particles of metallic copper were obtained after elutriation. By this process, from 100 pounds of bell-metal, about 50 pounds of copper were extracted, containing only one per cent, of foreign matters. 3. The washed scoriae were mixed with | their weight of pulverized charcoal; the mix- ture was triturated to effect a more intimate distribution of the charcoal ; and it was then put into a reverberatory hearth, in which, by aid of a high heat, a second reduction was effected, yielding a fluid alloy consisting of about 60 parts of copper and 20 of tin; while the surface of the bath got covered with new scorise, containing a larger proportion of tin than the first. 4. The alloy of 60 of copper with 40 of tin was next calcined in the same reverbera- tory furnace, but with stirring of the mass. The air, in sweeping across the surface of the bath, oxydized the tin more rapidly than the copper ; whence proceeded crusts of oxyde that were skimmed off from time to time. This process was continued till the metallic alloy was brought to the same standard as bell-metal, when it was run out to be subjected to the same operations as the metal of No. 1. The layers of oxyde successively removed in this way were mixed with charcoal, and reduced in a foumeau a manchef or Scotch lead smelting furnace. I shall not prosecute any further the details of this complicated process of Fourcroy ; because it has been superseded by a much better one contrived by M. Breant. He em- ployed a much larger quantity of charcoal to reduce the scoriae rich in tin; and increased the fusibility by adding crushed oyster-shells, bottle glass, or even vitrified scoriae, ac- cording to the nature of the substance to be reduced ; and he treated them directly in a reverberatory furnace. The metal, thus procured, was very rich in tin. He exposed it in masses on a sloping hearth of a reverberatory furnace, where, by a heat regulated according to the proportions of the two metals in the alloy, he occasioned an eliquation or sweating out of the tin Me- tallic drops were seen to transpire round the alloyed blocks or pigs, and, falling like rain, flowed down the sloping floor of the furnace ; on whose concave bottom the metal collect- ed, and was ladled out into moulds. When the alloy, thus treated, contained lead, this inetal was found in the first portions that sweated out. The purest tin next came forth, while the last portions held more or less copper in solution. By fractioning the products* therefore, there was procured — 1. Tin with lead. 2. Tin nearly pure. 3. Tin alloyed with a little copper. A spongy mass remained, exhibiting sometimes beautiful crystallizations ; this mass, eommonly too rich in copper to afford tin by liquation, was treated by oxydizeraent. In this manner, M. Breant diminished greatly the reductions and oxydations; and therefore incurred in a far less degree the enormous waste of tin, which flies off with the draught of air in high and long-continued heats. He also consumed less fuel as well as labor, and obtained purer products of known composition, ready to be applied directly ia many arts. He treated advantageously in this manner more than a million of kilogrammes (1000 tuns) of scoriae, for every 2 cwts. of which he paid 40 centimes (four-pence), while sev- eral million kilogrammes of much richer scoriae had been previously sold to other refiners at 5 centimes or one sous. I have said that the ancients made their tools and military weapons of .Bronze. Scr- eral of these have been analyzed, and the results are interesting. An antique sword, found in 1799, in the peat moss of the Somme, consisted of copper 87-47; tin 12-53, in 100 parts. The bronze springs for the balistae, according to PhUo of Byzantium, were made of copper 97, tin 3. Hard and brittle nails afforded by analysis, 92 of copper, and 8 of tin. Of three antique swords found in the env'rons of Abbeville, one was found to consist of 85 of copper to 15 of tin. The nails of the handle of this sword were flexible ; they were composed of copper 95, tin 5. Another of the swords consisted of 90 of copper and 10 of tin ; and the third, of 96 copper, with 4 tin. A fragment of an ancient scythe afforded to analysis 92*6 copper, and 7*4 tin. The process of coating copper with tin, exemplifies the strong aflinity between the two metals. The copper surface to be tinned is first cleared up with a smooth sand- 1^ (( COPPER. 487 stone; then it is heated and rubbed over with a little sal ammoniac, till it be perfectlj clean and bright : the tin, along with some pounded rosin, is now placed on the fopper, which is made so hot as to melt the tin, and allow of its being spread over the surlace with a dossil or pad of low. The layer thus fixed on the copper is exceedingly thin ; Bayeo found that a copper pan, 9 inches in diameter and 3J inches deep, being weighed imme- diately before and after tinning, became only 21 grains heavier. Now as the area tinned, including the bottom, amounted to 155 square inches, 1 grain of tin had been spread over nearly 7^ square inches ; or only 20 grains over every square foot. Copper and Jrsenic form a white-colored alloy, sometimes used for the scales of thermometers and barometers; for dials, candlesticks, &c. To form this compound, suc- cessive layers of copper clippings and white arsenic are put into an earthen crucible; which is then covered with sea salt, closed with a lid, and gradually healed to redness. If 2 parts of arsenic have been used with 5 of copper, the resulting compound com monly contains one tenth of its weight of metallic arsenic. It is white, slightly ductile, denser, and more fusible than copper, and without action on oxygen at ordinary temperatures ; but, at higher heats, it is decomposed with the exhalation of arsenions acid. The white copper of the Chinese consists of 40*4 copper; 31*6 nickel; 25*4 zinc; and 26 iron. This alloy is nearly silver white; it is very sonorous, well polished, malleable at common temperatures, and even at a cherry red, but very brittle at a red-white heat. "When heated with contact of air, it oxydizes, burning with a white flame. Its specific gravity was 8*432. When worked with great care, it may be reduced to thin leaves, and to wires as small as a needle. See German Silver, infra. Tutenag, formerly confounded with while copper, is a different composition from the above. Keir says it is composed of copper, zinc, and iron ; and Dick describes it as a short metal, of a grayish color, and scarcely sonorous. The Chinese export it, in large quantities, to India. Copper, White, or German silver. M. Gersdorf, of Vienna, states, that the propor tions of the metals in this alloy should vary according to the uses for which it is destined. When intended as a substitute for silver, it should be composed of 25 parts of nickel, 25 of zinc, and 50 of copper. An alloy better adapted for rolling, consists of 25 of nickel, 20 of zinc, and 60 of copper. Castings, such as candlesticks, bolls, &.C., may be made of an alloy, consisting of 20 of nickel, 20 of zinc, and 60 of copper; to which 3 of lea^ are added. The addition of 2 or 2J of iron (in the shape of tin plate ?) renders the pack fong much whiter, but, at the same time, harder and more brittle. Keferstein has given the following analysis of the genuine German silver, as madefros the original ore found in Hildburghausen, near Suhl, in Henneberg : — Copper - - - 40*4 Nickel 31-6 Zinc .... 25*4 Iron ..... 2*6 100*0 !1 Chinese packfong, according to the same authority, consists of 5 parts of copper, aDoj ed with 7 parts of nickel, and 7 parts of zinc. The best alloy for making plummer blocks, bushes, and steps for the steel or iron gtxd geons and pivots of machinery to run in, is said to consist of 90 parts of copper, 5 ol zinc, and 5 of antimony. A factitious protoxyde of copper, of a fine red color, may be made by melting together with a gentle heat, 100 parts of sulphate of copper, and 59 of carbonate of soda in crys tals, and continuing the heat till the mass become solid. This being pulverized antf mixed exactly with 15 parts of copper filings, the mixture is to be heated to whiteness, in a crucible, during the space of 20 minutes. The mass, when cold, is to be reduced \i powder, and washed. A beautiful metallic pigment may be thus prepared, at the cost of 2s. a pouud. All the oxydes and salts of copper are poisonous ; they are best counteracted by ad ministering a large quantity of sugar, and sulphureted hydrogen water. The following scientific summary of copper ores in alphabetical order may prove ac- ceptable to many readers, amid the present perplexing distribution of the native metallic compounds in mineralogical systems. 1. Jtrseniate of Copper. A. Erinite, rhomboidal arseniate of copper, micaceous copper, kup/er glimmer. Emerald green: specific gravity 4*043; scratches calc-spar; yields water by heat: fusible at the blowpipe, and reducible into a white metallic globule. Soluble in nitric acid; the solution throws down copper by iron. It consists of arsenic acid 33*78; oxyde of copper 59-24; water 5; alumina 1*77. It is found in Cornwall, Ireland, Hungary. B. Liroconite ; octahedral arseniate of copper ; lens ore, so called fn»n the flatnesi I; Ill «■ [I I' t 488 COPPER. COPPER. 48$ I *" ' I rf ihe cr^'stal. BIjc; specific gravity 2-88; scratches calc-spar. It consists of aretnie ftcid 14; oxyde of copper 49; water 35. It is found in Huel-Mutrel, Huel-Gorland, Iliiel-Unitv, mines in Cornwall. C. OHvenile ; right prismatic arseniate of copper ; olive-ore. Dull green ; specific gravity 4-28 ; scratches fluor ; yields no water by heat ; fusible at the blowpipe into a glassy bead, enclosinsr a white metallic grain. It consists of arsenic acid 45, oxyde of copper 50-62. It affords indications of phosphoric acid, which the analysts seem to have overlooked It occurs in the above and many other mines in Cornwall. D. Jphane.se. Trihedral arseniate of copper. Bluish green, becoming gray upon the surface ; specific gravity 4*28 ; scarcely scratches calc-spar ; yields water with heat ; ani? traces of phosphoric acid. The fibrous varieties called wood copper, contain water, and resemble the last species in composition. 2. Carbonate of Copper. A. ^2ttn7g; kupferlazur. Blue. Crystallizes in oblique rhomboidal prisms ; specilie gravity 3 to 3-83 ; scratches calc-spar, is scratched by fluor; yields water with heat, and blackens. Its constituents are, carbonic acid 25-5 ; oxyde of copper 69*1 ; water 5-4. The Chessy and Banat azurite is most profitably employed to make sulphate of copper. B. Malachite ; green carbonate or mountain green. Crystallizes in right rhomboidal prisms ; specific gravity 3*5 ; aflbrds water with heat, and blackens. It consists of car- bonic acid 18-5; oxyde of copper 72 2; water 9*3. C. Mysorine ; anhydrous carbonate of copper. Dark brown generally stained green or red ; conchoidal fracture ; soft, sectile ; specific gravity 2'62. It consists of carbonic acid 16-7; oxyde of copper 60-75 ; peroxyde of iron 19-5; silica 2'10. This is a rare mineral found in the Mysore. 3. Chromate of Copper and Lead ; vauquelinite. Green of various shades ; specific gravity 6-8 to 7-2; brittle; scratched by fluor; fusible at the blowpipe with froth and the production of a leaden bead. It consists of chromic acid 28-33 ; oxyde of lead 60*87; oxyde of copper 10*8. It occurs at Berezof in Siberia along with chromate of lead. 4. Dioptase; silicate of copper; emerald copper. Specific gravity 3-3 ; scratches glass with difficulty ; affords water with heat, and blackens ; infusible at the blowpipe. it consists of silica 43-18; oxyde of copper 45-46; water 11-36. This rare substance comes from the government of Kir^is. The silicate of Dillenberg is similar in composition. 5. Gray copper ore called Panabase, from the number of metallic bases which it contains; and Fahlerz. Steel gray ; specific gravity 4-79 to 5-10; crystallizes in regular tetrahedrons; fusible at the blowpipe, with disengagement of fumes of antimony and occasionally of arsenic ; swells up and scorifies, affording copper with soda flux. Is acted upon by nitric acid with precipitation of antimony ; becomes blue with ammonia ; yields a blue precipitate with ferrocyanide of potassum ; as also indications frequently of zinc, mercnrv, silver, &c. Its composition which is very complex is as follows : sulphur 26-83 ; antimony 12-46; arsenic 10*19; copper 4060; iron 4-66; zinc 3-69; silver 0-60 Some specimens contain from 5 to 31 per cent, of silver. The gray copper ores are very common; in Saxony; theHartz; :!r)rnwall; at Dillenberg ; in Mexico < Peru, &c. They are important on accounLboth of their copper and silver. TennantHe is a variety o( Fahlerz. It occurs in Cornwall. Its constituents are, sulphur 28-74 ; arsenic 11-84 j copper 45-32 ; iron 9-26. 6. Hydrated silicate of Copper ; or Chrysocolla. Green or bluish green ; specific gravity 203 to 2-16; scratched by steel ; very brittle; affords water with heat, and blackens; is acted upon by acids, and leaves a silicious residuum. Solution becomes blue with ammonia. Its constituents are silica 26 ; oxyde of copper 50 ; water 17 ; carbonic acid 7. 7. Muriate of Copper. Gtakamite; green; crystallizes in prisms; specific gravity 4*43. Its constituents arc, chlorine 15-90; copper 14-22; oxyde of copper 54-22; water 14'16; oxyde of iron 1*50. The green sand of Peru, collected by the inhabitants of Atakama, is this substance in a decomposed state. 8. Oxyde of Copper. A. Black, or Melaconise ; a black earthy looking substance found at Chessy and other places. It is dentoxydc of copper. B. Protoxyde or red oxyde of copper ; ziegelerr. Crystallizes in the regular octahe dron; specific gravity 5-69 ; scratches calc-spar; fusible at the blowpipe into the black oxyde ; and reducible in the smoke of the flame to copper ; acted upon by nitric acid with disengagement of nitrous gas; solution is rendered blue by ammonia. Its constitu- ents are oxygen 11*22 ; copper 88*78. It occurs near Chessy, and upon the eastern slope of the Altai mountains. 9. Phosphate of Copper. Dark green ; crystallizes in octahedrons ; specific gravity 3*6 to 3-8; scratches calc-spar ; yields water with heat; and affords metallic coppci i i with soda flux j acted on by nitric acid. Its constituents are, phosphoric acid 28*7 ; oxyde of copper 639; water 7*4. It occurs at the mines of Libethen in Hungary. 10. Pyri'ous Copper ; Kupferkies; a metallic looking substance, of a bronze-yellow color, crystallizing in octahedrons which pass into tetrahedrons; specific gravity 4-16; fusible at the blowpipe into beads attractable by the magnet, and which afterwards afford copper with a soda flux; soluble in nitric acid; solution is rendered blue by am- monia, and affords an abundant precipitate of iron. Its composition is, sulphur 36; copper 34-5; iron 30-5; being a combined sulphuret of these two metals. This is the most important metallurgic species of copper ores. It occurs chiefly in primitive forma- tions, as among gneiss and mica slate, in veins, or more frequently masses, in very many parts of the world — Cornwall, Anglesea, Wicklow, &c. It is found among the early secondary rocks, in Shetland, Yorkshire, Mannsfeldt, &c. The finest crystallized specimens come from Cornwall, Derbyshire, Freyberg, and Saint Marie-aux-Mines in France. 11. Sekniale of Copper ; Berzeline. Is of metallic aspect ; silver white; ductile; fusi- ble at the blowpipe into a gray bead, somewhat malleable; is acted upon by nitric acid; consists of selenium 40 ; copper 64, 12. Sulphate of Copper ; Cyanose. Blue; soluble, &c. like the artificial sulphates^ which see. Brochantite is a subsulphate of copper, observed in small crystals at Ekaterinenbourg in Siberia. 13. Sulphuret of Copper; Kupferglanz. Of a steel gray metallic aspect; crystallizes in rhomboids ; specific gravity 5*69 ; somewhat sectile, yet brittle ; fusible with intu- mescence at the blowpipe, and yields a copper bead with soda ; soluble in nitric acid ; becomes blue with ammonia, but lets fall scarcely any oxyde of iron. Its constituents are sulphur 19; copper 79'5; iron 0*75; silica 1*00. It occurs in small quantities in Cornwall, &c. The chemical preparations of copper which constitute distinct manufactures are, Blue or Roman vitriol ; for which see Sulphate of Copper ; Scheele's green and Schweinurtb green, Verdiler, and Verdigris. See these articles in their alphabetical places. The copper mines, now so important, were so little worked until a recent period, that in 1799 we are told in a Report on the Cornish mines, "it was not until the begin- ning of the last century that copper was discovered in Britain." This is not correct for in 1250. a copper mine was worked near Keswick in Cumberland. Edward HI. granted an indenture to John Ballanter and Walter Bolbolter, for working all "mines of gold, silver, and copper;" but that the quantity found was very small is proved from the fact that Acts of Parliament were passed in the reigns of Henry VIII. and Edward VI. to prevent the exportation of brass and copper, "lest there should not be metal enough left in the kingdom, fit for making guns and other engines of war, and for household utensils;" and in 1665 the calamine works were encouraged by the govern- ment^ as " the continuing these works in England will occasion plenty of rough copper to be brought in." At the end of the seventeenth century some "gentlemen from Bristol made it their business to inspect the Cornish mines, and bought the copper for 2/. lOs. per ton, and scarce ever more than 41. a ton." In 1700, one Mr. John Costor introduced an hydraulic engine into Cornwall, by which he succeeded in draining the mines, and "he taught the people of Cornwall also a better way of assaying and dressing the ore." The value and importance of copper mines since that period has been regularly increasing. During a terra of about 30 years 220 mines have sold their ores at ths Sublic sales. The following table (p. 490) from a report by Sir Charles Lemon, Bart L P., represents the progress of copper mining, from 1771 to 1837. « The produce of the copper mines of Cornwall since 1845, has been as follows. Years. Ore in Tons. Copper in Tons. Money Value. 1845 1846 1847 1848 1849 1850 162,557 150,431 155,985 147,701 146,326 155,025 12,883 11,851 12,754 12,422 11,683 12,254 £. t. 919,934 6 796.182 6 889,287 720,090 763,614 840,410 i 490 COPPER. Yeara. 1771 1780 1799 1800 1802 1805 1808 1809 1812 1814 1816 1818 1821 1825 1827 1831 1837 Tons of Ore. Tona of Copper. Total Value of Ore. 27,896 24,433 61,273 66,981 63,937 78,452 67,867 76,245 71,647 74,322 77,334 86,174 98,426 107,454 126,700 146,502 140,753 8,347 2,932 4,223 6,187 6,228 6,234 6,796 6,821 6,720 6,369 6,697 6,849 8,514 8.226 10,311 12,218 10,823 189,609 171,231 469,664 660,926 445,094 864,410 495,303 770,028 649,665 627,501 447,959 686,006 60.5,968 726,353 745,178 817,740 908,613 Standard Value per Ton. 81 83 121 133 111 170 100 143 111 130 98 166 103 124 106 100 119 With the improvements m the construction of the steam-engine, the facilities for working the mines have been increased, The first steam engine employed in the county was set to work at Huel Vor tin mines, near Helstone, in 1713, by Newcomen- but it was not until the reconstruction of the engine was effected by Watt that steam power was generally employed for draining the mines. The rapid advance made br Cornish engineers in the perfection of their engines will be seen by the following return of the duty, that is, the performance of each, which is reckoned by the number of nuilions of pounds lifted a foot high by the consumption of a bushel of coals •— Name of Mine. Highest Duty. Stray Park, 1813 Dolcoath, 1816 Consolidated Mines, 1822 Consolidated Mines, 1827 Fowey Consols, 1834 United Mines, 1842 Copper exported :— 29,000,000 40,000,000 44,000,000 67,000,000 97,000,000 108,000,000 Years ending 5th January, 1825 - 1826 - 1827 - 1828 - 1829 - J830 - 1831 - 1832 - 1833 - 1834 - 1835 - 1836 - 1837 - Wrought. To all parts. Tons. 6327 6172 5171 5855 5417 4787 5948 6105 Unwroufht. To India. Tons. 1801 2317 2423 2312 1769 2104 1993 1588 To all paru. Totu. 960 Total. To ail part*. I Tmu. I 130 1329 1079 2682 8,009 3150 9,322 3714 8,885 4569 10,424 4019 9,436 5283 10,072 5935 11,883 3909 10,014» * Supplement to the Mining Jouma<, Feb. 98, 1838. COPPER. 491 i Statistics of Copper for Cornwall in 1837-— The total quantity of ore sold was 142,089 tons (of 21 cwts.) yielding an average produce of eight per cent; the quantity of fine copper being 11,209 tons 1 cwt; and the average price of the ore 5/. 153. 6orts. 1850. 1851. 1850. 1851. 1850. 1851. 1850. 1851. 1850. 1851. Copper ore and regulus, tons. unwrought and part wrought, cwts. bricks and pige, cwts. - sheets, nails, &.C. (in- cluding mixed or yel- low metal for sheath- ing), cwts. wrought of other sorts, cwts, - - . 45,862 97,621 • * 42,476 106,064 * • 45,705 83,626 42,219 103,500 * . 16,685 25,746 - • 154,678 263,008 8,468 l'u,939 216,075 19,939 2,285 523 211 647 Coppering Iron and Zixa The great advantages which would arise from per- fecting a plan whereby the easily oxidizable metals, such as iron and zinc, could be coated with copper at a cheap rate, induced Messrs. Eisner y ^P^^^^^^ of sea polvpus, which construct in concert immense ramified habitations consisting of an assen^blage of small cells, each the abode of an animal The cora ^^ therefore a real poWpary, which resembles a tree stripped of its leaves. It has no roots, bu a foot not unUke a hemispherical skull-cap, which applies closely to every point of the s»»(a«7P«J wh ch ft stands, and is therefore difficult to detach. It ^^f.^y.rVwnot o an orX Tort to the coral, but contributes in no manner to its growth, like the root of an ordi- Sarv tree for detached pieces have been often found at the bottom of the sea m a state of hfcrease and reproduction. From the above base a stem, usually sing e. proceeds, which Ipldors™^^^^ an inch in diameter, and from it a small number of branches rannify in very TrreX dir^^ ^Mch studded over with cells, each containing an insect Th7DoTvf i when they extend their arms, feelers, or tenfacula, resemble flowers, whence. Is well arfr Jm the fo^rm of the coral, they were classed among vegetable productions. Thev are now styled zoophites by the writers upon Natural History. The fin^st^oral is found in the Mediterranean. It is fished for upon the coasts of Provence, and constitutes a considerable branch of trade at Marseilles. The coral is at- Mn the fir^t of those analyses, the phosphoric acid was estimated by M. Schulze's method, as per- phosphate of iron ; in the second, as phosphate of lead. - lached to the submarine rocks, as a tree is by its roots, but the branches, instead of growing upwards, shoot downwards towards the bottom of the sea ; a conformation favorable to breaking ihem ofl' and bringing them up. For this kind of fishing, eight men, who are excellent divers, equip a felucca or small boat, called commonly a coral- line. They carry with them a large wooden cross, with strong, equal, and long arms, each bearing a stou^ oag-net. They attach a strong rope to the middle of the crosa^ and let it down horizontally into the sea, having loaded its centre with a weight sufficient to sink it The diver follows the cross, pushes one arm of it after another into the hol- lows of the rocks, so as to entangle the coral in the nets. Then his comrades in the boa! pull up the cross and its accompaniments. Coral fishing is nearly as dangerous as pearl fishing, on account of the number of shark| which frequent the seas where it is carried on. One would think the diving-bell in its now very practicable slate might be employed with great advantage for both purposes. Coral IS mostly of a fine red color, but occasionally it is flesh-colored, yellow, or white. The red is preferred for making necklaces, crosses, and other female ornaments. It il worked up like precfeus stones. See Lapidary. CORK (Liege, Fr. ; Kork, Germ.) is the bark of the quercus liber, Linn., a species of oak-tree, which grows abundantly in the southern provinces of France, Italy, and Spain. The bark is taken off* by making coronal incisions above and below the portions to be removed; vertical incisions are then made from one of these circles to another, whereby the bark may be easily detached. It is steeped in water to soften it, in order to be flat- tened by pressure under heavy stones, and next dried at afire which blackens iU surface. The cakes are bound up in bales and sent into the market. There are two sorts of cork, the white and the black ; the former grows in France and the latter m Spain. The cakes of the white are usuaUy more beautiful, more smooth, lighter, freer from knots and cracks, of a finer grain, of a yeUowish gray color on both sides, and cut more smoothly than the black. When this cork is burned in close vessels It forms the pigment called Spanish black. This substance is employed to fabricate not only bottle corks, but small architectural and geognostic models, which are very convenient from their lightness and solidity. The cork-cutters divide the boards of cork first into narrow fillets, which they after wards subdivide into short parallelopipeds, and then round these into the proper conical or cylindrical shape. The bench before which they work is a square table, where 4 workmen are seated, one at every side, the table being furnished with a ledge to prevent the corks from falhng over. The cork-cfu tier's knife is a broad blade, very thin, and fine edged. It is whetted from time to time upon a fine-grained dry whetstone. The work- man ought not to draw his knife edge over the cork, for he would thus make misses, and might cut himself, but rather the cork over the knife edge. He should seize the knife with his left hand, rest the back of it upon the edge of the table, into one of the notches made to prevent it from slipping, and merely turns its edge sometimes upright and some- times to one side. Then holding the squared piece of cork by its two ends, between his finger and his thumb, he preseats it in the direction of its length to the edge : the cork is now smoothly cut into a rounded form by being dexterously turned in the hand. He next cuts ofl- the two ends, when the cork is finis;hed and thrown into the proper basket along. 6iae, to be afterwards sorted by women or boys. Of late years a much thicker kind of cork boards have been imported from Catalonia, from which longer and better corks may be made. In the art of cork-cutting the French surpass the English, as any one may convince himself by comparing the corks of their champagne bottles with those made in this countrj% Cork, on account of its buoyancy in water, is extensively employed for making floats to fishermen's nets, and m the construction of life-boats. Its impermeability to water nas \ed to its employment for inner soles to shoes. When cork is rasped into powder, and subjected to chemical solvents, such as alcohol, &c., It leaves 70 per cent, of an insoluble substance, called suberine. When it is treated , with nunc ac.d it yields the following remarkable products: — White fibrous matter 0-18, resm 14-72, oxahc acid 16-00, suberic acid (peculiar acid of cork) 14-4 in 100 parts. ^ *-* •* »" *wv Machine cork-cutting. — A patent was obtained some years ago by Sarah Thomson for this purpose. The cutting of the cork into slips is effected by "fixing it upon the sliding bed of an engine, and bnngmg it, by a progressive motion, under the action of a circular knife, by which it is cut into slips of equal widths. The nature or construction of a rnachine to be used for this purpose may be easily conceived, as it possesses no new me- chanical feature, except m its application to cutting cork. The motion communicated w me Knife by hand, steam, horse, or other power, moves at the same time the bed also Which carries the cork to be cut. The second part of the invention, viz., that tor -Separating the cork into square pieces alter it has been cut into slips as above, is effected by a moving bed as before, upon which 498 COTTON DYEING. i I V the slips are to be placed and submitted to the action of a cntfinc i.^ i,- v regulated to chop the cork into pieces of any given len/tb ^ '^''' ^^'""^ "''^^ ^ Ihe third part of the invention, viz., that for rounding or finishin., th. % of an engine to which is attached a circular knife that turns vlr«?i.^ *'T^'' ^^""'"^ or frame upon its side that revolves on its axle horizon tlZ ''''"^' "^^ * «""««« a pTet :rt;74.::rert^erb^^^^^^^^ f -<^^!^ -peetively to hold pendicularlj ; which c^rps arTcrntXd to hav. 11^ ^f 'T^'"^ '^ lengthways per- at the low J'end of their a^xlesTrrlin^ln^'^:;^^^^^^^^ "^^^^^"' ^^ "^^^ ^^^ P-- orrn^Xr'SiVtVew^^^^^^^ the circular knife revolvesTertic^l v tLfr^^. . ^-'^'^^^l ^'l^ ^^ ^^" ««™^ ^ime that cork, turns horizontal! jXin.Tnrt^h^^ containing the clamps with the pieces of to render each piece of cork of ,"nHrt„? Tk i ^^ """^ "P *^ *^^ ^^^^ ^^ ^^^ knife, when, axes, independ^t^; of ?heir^e^^^^^^^^^ "^^Tf ^^^scribed, revolve upon thei; cork is brought under the action l^fLT v !u ""^^"« ^^^ whole circumference of the off, and the f ork^finfsVetroTh Id ytti^ '""^iToZS^:'' ?" T^'T'^ ^'^'^ Bumption amount* to about 2200 tons /e7an" urn ^ ^ '"^""'^ ^^^ ^^™' ^*^°- CORROSIVE SUBLIMATF- k;«m^^-I *°!^"™- CORUNDriM '^^iJ.^^^.^AJ^; bichloride of mercury. COTTON FACTORY. Alumina Lime Silica - Oxide of iron Blue Sapphire, China. 98-5 0-5 0-0 10 84-0 0-a 6-6 7-6 Corundum, Bengal 89-5 0-0 6-6 1.25 Emery, Naxoa. 86-0 3 8-0 4-0 100-0 Klapr. | 980 Chen. | 982 Tennent | 96-0 Tennent. The perfectly white crystals of sapphire are pure alumina. OrlnTal r^brofTl^rtheSa^^^^^^^^^^^ ^^^/^hire so called, and the 3-97. Their form is a Si v acute rhomho;^ 1m 'P'"'^" ^'l''^^^' ^^'"^ ^'^ «g«in«t inferior in hardness onlyfo tL di^^^^^^^ ^T ^'-^ ''^'^^'T' ^"^ ^« COTTON nvvmr ,>W'7 ^' i*^^ ^^PP"'^^ occurs also in 6-8ided prisma CoVton an? hSen yfrS and" doth. Iv^'"' ^^'ll ^---^-^-llen/arberei, ^Gen^.) may therefore wrh^propriety be t e^^^ T/ Ln^% T'.."®"^^^./^^ ^>'^^' ^"^ =U reSi^H^^S^^^^ ^^^^^ ^s;Xi-^^l^{=^ rr^^^^^ fix these particles so that thevVm not ^^^ ?''f^ 'f^ ''^""^"^^ properties as wiU be subjected All tL ^nL ^u^i • separate, to whatever ordinary trial they mav tunal ydonotZe^sth^^^^^^^^ ^"^'^ bedesirable to transfer to these stuffs unTor! constancy a^eHt the dfscovTr^^^^^^^^^^ ^"'^ °^ '"'"'" ""^"^"^ ^" '^'' ^"^PO'-^^"t art have of fast colo^ those dyes whTr.7 fr^.T "'"^ ^'■^'''''^ ^^^"^ "^^^ ^^^"^^^'^ ^^^o the class goods manufactu?^ of cotTon flax or hemn ^^-'.^^n ^""z"'^'' ^^'"^^^ ^» ^^« therefore, to be so dyed as to Jesi J'the nH' ^"^'""^^ ^** ?^ ''^'^^^' ^"'i «"gt»^ the laundry. Vitalis distin°u?she1 HvZl Jn.t ^l'^ '^^^^ '°^"^'°"^ commonly used in fancy-colored (pefitteint) "^^^^^^^ 'v^^ ^^^^ ^^^^^^^5 1. the >^7i>e, or boils with soapr2 ho fwhiTh re J^^^^^^ ^^V T ^''''''^'^ ^^ ^^ '' ^^o fast colors (^rand teint) T^Tll^l ^^Brt^^^^ may be called Kie fugitive; those made with madd^wkhnnf^ ^^1^°^"^^' "^^^^^^^ safflower, &c., der with an oily mordant, a e A^/It^ hoi? ^''^ ^"-l^' ^""^ «^«^'^'' ^"'I those of mad^ for giving theseVerentW^^^^^^^ t::^'i^::^^ ^^^^' -^ -^- P-esses atiLtf"ci^T^^p;,r^^^^^^^^^ Parag^phs, the oper'aSs conducive to the fix- J;mpt:'d^otvV[^^^^^^^^^^ S^eTeptatr ^2 i'rlV^^ ^"^ 1^? ""'^^''' pound of cotton, being coarseLf pounded are?o hpn^:* • . "^"""^ of galls for every 30 gallons of water fof over, loVpo^s^r^tl'TaaXri:?^^^^ I*-- •> 499 of galls feel pasty between the fingers. The fire being withdrawn, when the bath becomes moderately cool, it is passed through a hair-cloth sieve. If during this operation the liquor should become cold, it must be made once more as hot as the hand can bear. A portion of it is now transferred into another vessel, called a back, in which the cotton is worked till it be well penetrated with the decoction. It is then taken out, wrung at the peg or squeezed in a press, and straightway hung up in the drying-houst. Some more of the fresh decoction being added to the partially exhausted liquor in the back, the pro cesj is resumed upon fresh goods. The manipulation is the same with sumach, but the bath is somewhat differently made; because the quantity of sumach must be double that of galls, and must be merely infused in very hot water, without boiling. When galls and sumach are both prescribed, their baths should be separately made and mixed together. 2. »4Iuming. Alum is a salt which serves to prepare cotton for receiving an indefinite variety of dyes. Its bath is made as follows : For 100 pounds of scoured cotton, about 30 gallons of water, being put into the copper, are heated to abou .2^^., when 4 ounces of alum, coarsely pounded, are thrown in for every pound of cotton, and instantly dis- solved. Whenever the heat of the bath has fallen to about 98° F., the cotton is well worked in it, in order that the solution may thoroughly penetrate all its pores. It is then token out, wrung at the peg or squeezed in the press, and dried in the shade. The solu- tion of alum is of such constant employment in this kind of dyeing, that it should be made in large quantities at a time, kept in the alum tun, where it can suffer no deteriora tion, and drawn off by a spigot or stop-cock as wanted. There are certain colors which require alum to be deprived of a portion of its acid ex- cess, as a supersalt; which may be done by putting 1 ounce of crystals of soda into the tun for every pound of alum. But so much soda should never be used as to cause any permanent precipitation of alumina. When thus prepared, it is called saturated alum though It is by no means neutral to litmus paper; but it crystallizes differently from ordi- nary alum. Cotton does not take up at the first aluming a sufficient quantity of alum ; but it must receive a second, or even a third immersion. In every case the stuff should be thoroughly dried, with an interval of one or two days between each application ; and it may even be left for 10 or 12 hours moist with the alum bath before being hung in the air. When the cotton is finally dry, it must be washed before being plunged into the dye bath ; other- wise, the portion of alum not intimately combined with the cotton, but adherin* exter- nally to its filaments, would come off by the heat, mix with the bath, alter th'i color by dissolvmg in it, and throw it down to the bottom of the copper, in the form of a lake to Ihe great loss of the dyer. Madder reds, weld yellows, and some other colors are more brilliant and faster when acetate of alumina, prepared with acetate of lead alum and a little potash, is used, than even saturated alum. This mordant is emnloved cold' and at 4° Ban me. ^ "' » 3. Mordants. See this article in its alphabetical place. 4. Dye baths are distinguished into two classes; the coloring bath, and the dyein«'bath The former serves to extract the coloring matters of the different substaiu.cs wfth the exception of madder, which is always used in substance, and never as an extract infu- sion, or decoction. In all these cases, when the color is extracted, thai is wnen the dye bath IS completed by the degree of heat suited to each substance, ii is tnen allowed to cool down a certain way, and the cotton is worked or winced through ii, to tH ihe wished for tmt. This is what is called the dye bath. Several coloring batns are made in the ^nli' * r ^, ^ ^^""^^ *° ^^^ "^^® ^" *^^ ^^^^ 5 ^"^ ^^® greater part require a heat of 90° or 100° to facilitate the penetration of the stuffs by the coloring particles. The descriotion of the several dye baths is given under the individual dyes. 5. Of the washing after the dyeing.— The washing of the cottons after they have re- ceived the dyes, is one of the most important operations in the business. If it is not care- ruUy performed, the excess of color not combined with the fibres is apt to stain whatever It touches. This inconvenience would be of little consequence, if the friction carried off the color equaLy from all the points ; but it does not do so, and hence the surface ap- pears mottled. A well-planned dye house should be an oblong gallery, with a stream of wrater flowing along m an open conduit in the middle line, a sWies of dash-wheels ar- ranged against the wall at one side, and of dyeing coppers,- furnished with self-acting jrincps or reels against the other. In such a gallery, the washing may be done either by hand, ny the rinsing machine, or by the dash-wheel, according to the quality of the dve ind the texture of the stuffs. And they may be stripped of the water either by the jack and pin, by the squeezin? roller, or by the press. Wooden pins are placed in some dye houses on each side of the wash cistern or pool. They are somewhat conical, U foot high 3i inches in diameter at the base, 1| at the top, are fixed firmly upright, and at a level of about 3 feet above the bottom of the cistern, so as to be handy for the workmen. 500 COTTON FACTORY. COTTON FACTORY. 501 1^ See Brazil Wood, Fustic, Madpek, Black Dye, Brown Dye. • > !i I * * n 3° I— t;— i-c— I C 10 ao io» *""'•-' I i t ■ ■ ■ 1 « I 1 890 i . COTTON FACTORY. 891 808 iiaiaiatid I [□ [a im PI la itaiiaijapu iiaiaiai i[aini.[ai[a IRREGULAR PAGINATION I 504 COTTON FACTORY. The attic story accommodates the warping mills, and the warp dressing machines subservient to power weaving. ^ ^ macnmea ^u"^^ winding machines, and some extra mules (self-actors) are placed in the winffs the live winding machines being in the two top rooms of the left wing. We shall briefly sum up the references in the ground-plan as follows: A, the grand apartment for the steam engines. B, the distribution of the carding engines, the moving shaft or axis runDine in a straight line through them, with its pulleys for receiving the driving bands. c, c, the drawing frames. D, D, the jack, or coarse bobbin and fly frames. E, E, the fine roving or bobbin and fly frames. the^d'anTsd fl^aT^"' ""^ ^^^ throstle frames, standing in pairs athwart the gallery, in G the mules are here represented by their roller beams, and the outlines of their head- stocks, as placed in the 5th and 6th stories. H, the looms with their driving pulleys projecting from the ends of their main axes. Sometimes the looms are placed in parallel straight lines, with the rigger pulleys of the one alternately projected more than the other, to permit the free play of the driying- belte ; sometimes the looms are placed, as generally in this engraving, alternately to the right and left, by a smal space, when the pulleys may all project equally. The former plan 18 the one adopted in Mr. Orrell's mill. J f J H J »"^'^*r I, represents the cast-iron girders which support the floors of this fire-proof building. f V^f* f V"-!f Ttu ^If^ "^ S;^^ ^rr* •" *^^ ^•^^"^^^ «^ » ^'°<^ of pilasters built againit «ie outside of the edifice. These hollow shafts are joined at top by horizontal pipes, which all terminate in a chest connected with the suction axes of a fan, whereby T con- stant draught of air circulates up the shafts, ventilates the apartments, and prevents the reflux of oflfensiye effluvia from the water-closets, however careless the work-people may be. Tlie tunnels toward the one end of the building are destined for the men; to- ward the other for the women. ' L, L, are the staircases, of a horse-shoe form, the interior space or shaft in the middle being used for the teagle or hoist In the posterior part of the shaft a niche or groove latform ^^'""^^^-^^'g'^^^ ^^ ^^'^^ i°. <>"* of the way of the ascending and descending M, M, are the two porters' lodges, connected to the corner of each wing by a handsome iron balustrade. They are joined by an iron gate. / }^ yj^l be observed that the back loom-shed has only one story, as shown in section, W ^91)- In the ground-plan of the shed, n represents the roofing, of wood-work. Ihe rafters of the floors rest at their ends upon an iron plate, or shoe with edges (as it 18 called), for the girders to bear upon. g ^aa n. The two steam engines, of fully 90 horse power each, operate by cranks, which stand at right angles upon the shaft marked a both in the plan and section In the centre, between the bearings, is a large cog-wheel, driying a smaller one upon the shaft marked 6 in both figures, to which the fly-wheel c belongs. That prime motion wheel is magnificent, and possesses a strength equal to a strain of 300 horses. From this shaft motion IS given to the main or upright shaft d, in the section, by two bevel wheels visible at the side and on the top of the great block of stone, about 6 tons weight (Jig. 391), which gives a solid basis to the whole moving apparatus. Ihe velocity of the piston in these steam engines is 240 ft per minute. ihe trst shaft makes 44 3 revolutions per minute; the main upright shaft 68-84 per minute. The steam engines make 16 strokes per minute; and the length of their stroKes is 7 it 6 in. As the one engine exerts its maximum force when the other has no force at all. and as the one increases as the other diminishes in the course of each pair of strokes, the two thus cooperate m imparting an equable impulsion to the great geering and shafts which, being truly made highly polished, and placed in smooth beafings of hard brass revolve most silently and without those vibrations which so regularly recurred in the frame "^^ ^^ ^ detrimental to the accurate performance of delicate spinning To the horizontal ramifications from the upright shaft any desired velocity of rotation may be given by duly proportioning the diameters of the bevelled wheels of communi- cation between them,- thus, if the wheel on the end of the horizontal shaft have one half or one third the diameter of the other, it will give it a double or a triple speed. In the lowest floor, the second bevel wheel above the stone block drives the horizontal shaft e, seen m the ground plan ; and thereby the horizontal shaft /, at right angles to the former, which runs throughout the length of the building, as the other did through Its breadth, backward. The shaft / lies alongside of the back window wall, near tJe I i COTTON FACTORY. [503] ceiling ; and from it the tranverse slender shafts proceed to the right and left in the main buil5 12 self-actor mules, of 360 spindles each (720 spindles per horse power) 6-00 6 Danforth throstle frames, containing 570 spindles (96 in each), being 93 spindles to 1 horse power - - . . _ 6-20 At Boliington, in a worsted mill, he found that 106| spindles, including preparation took 1 horse power upon throstles. N. B. There is no carding in the long wool or worsted manufacture for merinos: — At Bradford, in Yorkshire, he found that a 40 horse power boat-engine, of Bolton & Watts, drove 698 calico looms, 6 dressing machines (equivalent to dress warp for 180 of the said looms), and 1 mechanic's workshop, which took 2 horses power. Othei engineers estimate 200 common throstie spindles, by themselves, to be equivalent to the power of 1 horse. COTTON FACTORY. 505 f 0'^ The shafts which drive the cards revolve about 120 times per minute, with a driving pulley of from 15 to 17 inches in (Jiameter. The shafts of the drawing, and the bobbin and fly frames, revolve from 160 to 200 times per minute, with pulleys from 18 to 24 inches in diameter. The shafts of throstle frames in general turn at the rate of from 220 to 240 times per minute, with driving pulleys 18 inches in diameter, when they are spinning yarn of from No. 35 to 40. The shafts of mules revolve about 130 times per minute, with pulleys 16 inches in diameter. ^ The shafts of power looms revolve from 110 to 120 times per minute, -with pulleys 15 inches in diameter. ^ The shafts of dressing machines revolve 60 times per minute, with pulleys 14 inches m diameter. ^ r j Before quitting the generalities of the cotton manufacture I way state the following facts communicated also by Mr. Bennet: — A wagon-shaped boiler, well set, will evaporate 12 cubic ft of water with 1 cwt of coals; and a steam boiler with winding flues will evaporate 17 cubic ft with the same weight of fuel : 7^2_ ibs. of coals to the former boiler are equivalent to 1 horse power exerted for an hour, estimating that a horse can raise 33,000 lbs. 1 foot high in a minute. The first cotton mill upon the fire-proof plan was erected, I believe, by the Messrs. ?o'r!i^*^ .u^ ?^JPi?'''ri'' ^^^ y''^'; ^^J^ ' ***^*' «^ ^«*^''«- P^»"'PS * Lee, at Manchester, in 1801 ; that of H. Houldsworth, Esq., of Glasgow, in 1802 ; and that of James Kennedy, at Manchester in 1805; since which time all good factories have been built fire-proof hke Mr. Orrell s. *^ * The heating of the apartment of cotton factories is eff'ected by a due distribution of cast-iron pipes, of about 7 or 8 inches diameter, which are usually suspended a little way below the ceilings, traverse the rooms in their whole length, and are filled with steam from boilers exterior to the building. It has been ascertained that one cubit foot of boiler will heat fully more than 2,000 cubic ft of space in a cotton mill, and maintain it at the temperature of about 75^ Fahr. If we reckon 25 cubit ft contents of water in a waggoned-shaped steam boiler as equivalent to 1 horse power, such a boiler would be capabe of warming 50,000 cubic ft of space; and therefore a 10 horse steam boiler will be able to heat 500,000 cubic ft of air from the average temperature, 50°, of our climate, up to 76° or perhaps even 80° Fahr. It has been also ascertained that in a well-built cotton mill, one superficial foot of exterior surface of cast-iron steam pipe will warm 200 cubic ft of air. In common cases for heating churches and public rooms, I believe that one half of the above heating sur- face will be found adequate to produce a sufficiently genial temperature in the air. The temperature of the steam is supposed to be the same with that in Mr Watt's low- pressure engines, only a few degrees above 212^^— the boiling point of water The pipes must be freely slung, and left at liberty to expand and contract under the changes of temperature, having one end at least connected with a flexible pipe of copper or wrought iron, of a swan-neck shape. Through this pipe the water of condensation is allowed to run off: The pipes should not be laid in a horizontal direction, but have a sufficient slope to discharge the water, llie pipes are cast from half an inch to three quarters thick in the metal. In practice the expansion of steam pipes of cast-iron may be taken at about one tenth of an inch in a length of 10 feet, when they are heated from a little above the freezing to the boiling point of water The upper surface of a horizontal steam pipe is apt to become hotter than the bottom, if the water be allowed to stagnate in it; the difterence being occasionally so great as to cause a pipe 60 feet long to be bent up 2 inches in the middle. In arranging the steam pipes provision ought to be made not only for the discharge of the water of condensation, as above stated, but for the ready escape of the air • other- wise the steam will not enter freely. Even after the pipes are filled with steam,' a litUe of It should be allowed to escape at some extreme orifice, to prevent the re-accnmulation of air discharged from the water of the steam boiler. In consequence of water being left in the pipes serious accidents may happen; for the next time the steam is admitted into them, the regu arity of heating and expansion is impeded, some part of the pipe may crack or a violent explosion may take place, and the joints may be racked to • very considerable distance, every way, from the place of rupture, by the alternate expansions and condensations. The pipes should therefore be laid, so as to have the least possible declivity, in the direction of the motion of the steam. Formerly, when drying rooms in calico printing works were heated by iron stoves or cockles, their inmates were very unhealthy, and became emaciated ; since they hive been heated by steam pipes the health of the people has become remarkably good, and their appearance frequently blooming. COTlbN MANUFACTURE. {Filature de Coton, Fr.; JBaumu>ollenspinnerte, 506 COTTON MANUFACTURE. Gem.) Colton is a filamentous down, which invests t5ic seeds of the plant called iw. i^Mim by Linnaeus, and placed by him in the class monadelphia, and order monandHa Dut belongmg to the natural family of malvacea:. It has a cup-shaped calyx obtusely five-toolhed, enclosed in a three-clefl exterior calyx ; the leaflets are united at their base of a heart shape, ind toothed; stigmas three to five; capsule three to five celled and many seeded ; seeds bearing a downy wool. Thirteen species are described by Decan- dolle, but their characters are very uncertain, and no botanist can assign to a definite species of the plant, the very dissimilar staples of the cotton filaments found in commerce The leaves are generally palmate and hairy; and the blossoms are large, and of a beau- tiful yellow. The gossypium religiosum of Tranqnebar has while blossoms in some of Its varieties, to which probably the white colton of Rome, cultivated in the Jardin des Plantes at Pans, belongs. The filaments differ in length, flexibility, tenacity, and thick ness, in difl^erent cottons, whence the great diflferences of their value to the cotton-spin- f "' fSox ^ P"7f. *=""^"t '" t^e market show. Thus, at Liverpool, on the 1st of Decem- fcer, ISd5, the following values were assigned to the following cottons :— COTTON MANUFACTURE. 507 Sea-island Demarara and Berbice Pernanibuco Egyptian New Orleans Bahia Upland Georgia West Indian Surat Madras Beneal 8. d. 1 6 to 9 lOf 111 8i d. 6 ll 2| 7| 7| 6| 10 111 9 8 8 eh But It IS to be observed, that there are varieties of the Sea-island Georgian cotton, so T?K IV ^^ ^^/ spinner of fine yam, as to fetch 3^., 4*., or even 5*. per pound. ine niaments of cotton, when examined with a good microscope, are seen to be more or less nband-iike, and twisted ; having a breadth varying from _L_ of an inch in the strongest Smyrna or candle-wick cotton of the Levant, to , »_ of ^ inch in the finest Sea-island. *^*"" «rrIn\^.^'"i'^'f'"fK'°r ^^^'^^^'' *'*'"°"' '" *^^ ^^ '^ *^^* «^ ^he black seeded and the f^uVL 7\ ^he former part with their downy wool very readily to a pair of simple latPr;.?«^ ti*" ^^^°^e nearly in contact, by the power of the human am; while the lal pS hi ^ T^^ ""'^^ ?°"*'^- ^^'i*^^' ^"^ '•^"^^^ *« ^« ?i"n«J» as the operation is ^Pr ^5^.V°T ir '''-, '^.^••^"^^'- saw-mechanism, usually driven by horse or water ^7vL tl^' T ^'?^^ v!' ^^"' separated from the seeds, it is packed in large S?P for tif^ ' ^^^^^^^y ^th the aid of a screw or hydraulic press, into a very denle 1^ of .nrt^ *^^"^^°'^!S! of transport. Each of the American bags contains about 34o flockv thlt h ; f ^'" this cotton is delivered to the manufacturer, it is so foul and S ^ tL . ^ """'^ ''^r'''' ^"'^ disentangle it with the utmost care before he can subject M 10 Ine carding operation. •' Fig. 390, A B, is a roller, about 9 inches in diameter, which revolves in the direction of the arrow. This cylinder consists of a parallel series of oblique pointed circular saws made fast to one axis, and parted from J each other by wooden rings nearly one inch and a half m thickness. Above the cylinder, is a kind of hopper IK E F, into which the ginner throws the seed cotton, which «r ♦».« o«^ ♦ ♦I. . . ?"^ ^P®" * grating, up through which small segments of the saw-teeth project so as to lay hold of the fibres in their revolution, and pull them through, while the seeds, being thus separated, roll down the slope of the grid, to be discharged from the spout i k. m is a cylindrical brush placed below the gmting, which revolves against the saw-teeth, so as to clear them of the adhering cotton niaments. ° The willow, which was originally a cylindrical willow basket, whence its name, but is BOW a box made of wood with revolving iron spikes, is the first apparatus to which cotton wool IS exposed, after it has been opened up, pickfti, and sorted by hand or a rake, m what is called a bing. The willow exercises a winnowing action, loosens the large flocks, and shakes out much of the dirt co„tained in them. The frame of the willow IS about 2 feet wide, and turns with its spikes at the rapid rate of 600 revolutions per minute, whereby it tosses the cotton about with great violence. The heavy im- purities fall down through the grid bottom. It is exposed, however, for only a few minutes to the action of this machine. For factories, which work up chiefly the coarser ind fouler cottons of India, and Upland Georgia, the conical self-acting willow ea 391 constructed by Mr. Lillie at Manchester, is much employed. In it, the cotton is put in at the narrow end of the truncated cone, which, being spiked, and revolving rapidly within a nearly concentric case upon a horizontal axis, wafts it on towards the wide end, while its impurities are partly shaken out through the grid or perforated bottom, and partly sucked up through revolving squirrel wire cages, by the centrifugal action of a fan. This is a powerful automatic engine, deserving the study of the curious, and is as safe as it is powerful. The cone of this huge machine makes from 400 to 600 turns per minute, and wiU clean 7200 pounds, or 24 bags, in a day. After shaking out the grosser impurities by the willow, the cotton spinner proceeds to separate each individual filament of cotton wool from its fellow, so as to prepare it for carding, and to free it from every particle of foreign matter, whether lighter or heavier than itself. This second operation is performed by what are called batting {beating), scutching, and blowing machines, which are all now much the same, what- ever difference of signification the name may have. Indeed, each machine not only beats, scutches, bU blows. Fig. 391 ex- hibits a longitudinal section of a good blowing engine of modern construction. The machine is about 18 or 19 feet long, and three feet across within the case. The whole frame is made of cast-iron, lined with boards, forming a close box, which has merely openings for introducing the raw cotton wool, for taking out the cleansed wool, and removing the dust as it collects at the bottom. These doors are shut du- ring the operation of the machine, but may be opened at pleasure, to allow the interior to be inspected and repaired. The introduction of the cotton is effected by means of an endless cloth or double apron, which moves in the direction of the arrow a a, at the left end of the figure, by passing round the continually revolving rollers at b and c. The two rollers at «, being the ones which immediately intro- duce the cotton into the jaws, as it were, of the machine, are called the feed rollers. The batting arm, or revolving diameter, /«, turns in the direction of the arrow, and strikes the flocks violently as they enter, so as to throw down any heavy particles upon the iron grating or grid at n, while the light cotton filaments are wafted onwards with the wind, from the rotation of the scutcher in the direction of arrow a\ along the second travelling apron, upon which the squirrel cage cylinder presses, and applies the cotton in the form of a lap. Above the cylindric cage h, which turns in the di- rection of its arrow, there is a pipe fe, the continuation of the case t. This pipe. though broken off" in the figure, com- municates by a branch pipe with an air- sucking fan ventilator, not seen in this figure, but explained under Foundry. The cage A, by its rotation, presses down, as we have said, the half cleaned cotton upon the cloth a', which carries it forward to the second scutcher /', by the second set of feed rollers e'. The second scutcher throws down the heavy dust upon the second grid n', through which it falls upon the bottom of the case. The first scutcher makes about 1280 strokes of each of its two arms in a minute ; the second 1300. The fbed rollers for each are fluted. The feed cloth is either sustained by a board, or is made of parallel spars of wood, to secure it against bagging, which would render th« 508 COTTON MANUFACTURE. P i I 392 delivery of the cotton irregular. The feed rollers malent of the pipe which leads to the suction fan, or ventilator. The tn.ckness of the lap i„ this machine must be nicely regulated, as it determine; in a great measure, the grist of the card-ends, and even the rovings. ' In 12 hours such a ^aj machine will prepare 650 pounds of cotton. ^ A B if fhfrJ.V!lf fh"' scutching machine, now never seen except in the oldest factories. A B is the feed cloth ; g h and m n are the two scutcher frames. ..^mm^ 393 ^^^z %i::.ZsTo'^tJ:,,t:^^^^^^^ th'emV^^*^-'^ ^^frt;!^ doubled up and convoluted, as thev usuallv «r7 • ^ lengthwise, instead of being machines. Carding consist in the r^ntnTl Jt-rl'' leaving the blowing and lap ^^^ 395 a MM > f, -- — m — • n »»- a flock or tuft of cotton placed between tL.^,pi!Tfr' Parallel. Now suppose in the direction of its arrowrand let fbe moved t th? "^ r^?""'- • ^"* ** ^ "°^^^ remain at rest. Every filam'ent of the cotrn wil be ^^0^^ b^^ T T?}""' t' When their surfaces are thus drawn over each other thP wh r ^ -.f ^ u^^ ?^ ^^f^^' forward direction, while those ofT will tpn^f..^' ^^^ ^eeth of a will pull them in a The loops or doublings wm by bot^mo^^^^^^ them, or to pull them backwanls. flocks will be converged jLLws of ^arX^fi? ^^ TT^ ^' ^'^^" °"^' ^° ^^^^ ^he other. Each tooth w 11 secure to iNelf ^Z ^l^^^^^ts, lying alongside or before each Let us suppose this end eflTected, and that all the fihrpe >,«^« v , r ^ , card a, a transverse stroke of 6 will draw over to it ^oLt • ^T transferred to the deed at each stroke there will be a new n^rth^on hit ll\ ""°'^'' ""^ ^^""^' "^ '»- parallelism, but still each card wilfrltaTa greaf deaTof thr T"^'' V"" ^"?^^^"^ rwnt«5-' ''' '-'' '' - ^^ ^^- "- X^lTr-.r^^:- combVut aTor'ZoT^^'hrfireill^^^^^^^ ^'^ ^^" ^"^^^^"^ eition, no power of retaining them Even t?e douWed Ty.r.T^V^ * ^T', '" '^'' ^ slopini? point of 6, in obedience to the traction of? If oops will slip over the positions of the cards, which take placl In hand eaVd. ^ '^^'k'""^ '^^'^ '^*^ 7^"'^^^ any person will be able to understand the nl^vn^o^rT^^^ ^l reversing one of them against another cylinder car^re respective tplthK ^y^'"}^^' ^^^d against its flat top, or position of /?g. 394; and also the pC^^^^^ in What maV be called the stripp^n^Stt^nV^g^^^^^^^^^^ ^^^^^"^' '""^ '^^'^ ^^^^^-^ we^ete^ngrntsTnv^rr^fllv'i Z^%:^j^^t f '''''''' 'T'^ ^^^^' «d brought into nearly their present "o^lt^sunr^^^ 510 COTTON MAMJFACTURE. COTTON MANUFACTURE. 511 » 1 V- Wi carding engine consists of one or more cylinders, covered with card-leather (somelimcf called card cloth), and a set of plane surfaces similarly covered, made to work against each other but so that their points do not come into absolute contact. Some cards consist entirely of cylinders, the central main cylinder being surrounded by a series of smaller ones called urchins or squirrels. These are used solely for preparing the coarser stapled cotton, and sheep's wool for the wool spinner. „. , , Fig. 396 represents a card of excellent construction, which may be called a breakef and finisher, as it is capable of working up the fleece roll of the lapping machine di rectly into a card-end or riband fit for the drawing machine. In fine spinning mills there are always, however, two cards ; one coarser, called a breaker, which turns off the cotton in a broad fleece of extreme thinness, which is lapped round a cylinder j and constitutes the material presented to the finisher card, which has teeth of a finci construction. a is one of the two upright slots, which are fixed at each side of the engine for re- ceiving the iron gudgeons of the wooden cylinders round which the fleece of the lapping machine is rolled. The circumference of this coil rests upon a roller 6, which is made 10 turn slowly in such a direction as to aid the unfolding of the lap by the fluted cylinders e. The lap proceeds along the table seen beneath the letter c, in its progress to the fluted rollers, which are an inch and one sixth in diameter, and have 28 fluiings in their cir- cumference, g is a weight which hangs upon the axis of the upper roller, and causes it to press upon the under one : / is the main card drum ; g g g) the arch formed by the flat top cards; h, the small card cylinder for stripping off the cotton, and therefore called the doffer, as we have said ; i, the doffer-knife or comb for stripping the fleecy web from the doffer ; klqm, Ihe lever mechanism for iBoving these parts. At d there is a door for permitting the tenter to have access to the interior of the engine, and to re- move whatever dirt, &c. may happen to fall into it. In fig. 397 we see the manner of fix- ing the flat tops g g over the drum ; and for making the matter clearer, three of the tops are removed. Upon the arched cast-iron side of the frame, a row of strong iron pins k are made fast in the middle line ; and each top piece hiife, at each of its ends, a hole, which fits down upon two such opposite pins. / I are screws whose heads serve as supports to the tops, by coming into contact with the bottom of the holes, which are not of course bored through the wood of the tops. By turning the heads of these screws a little the one way or the other, the pins may be lengthened or shortened in any degree, so as to set the tops very truly in adjustment with the drum teeth revolving beneath them, h' is the small runner or urchin, and t' the large runner ; both of which are spirally covered from end to end with narrow card fillets in the same manner as the doffer. The main drum is on the contrary covered with card cloth, in strips laid on parallel to its axis, with interjacent parallel smooth leather borders. The teeth of these several cards are set as represented in the figure, and their cylinders revolve as the arrows indicate. The runners as well as the doffer cylinder may be set nearer to or farther from the drum /; but the screws intended for this adjustment are omitted in the draw- ings, to avoid confusion of the lines. The card-end or fleece taken off the doffer h by the crank and comb mechanism « k m, passes through the tin plate or brass funnel riyfig. 396, whereby it is hemmed in and contracted into a riband, which is then passed through between a pair of drawing roll- ers 0. It is next received by the rollers u v, which carry it off with equable velocity, and let it fall into the tin cans placed below, or conduct it over a friction pulley, to be wound along with many other card-ends upon a lap roller or large bobbin. The latter nechanism is not shown in this figure. A sloping curved tin or brass plate^ channelled or ridged along its surface, conducts the card ribands separately ; there are two smooth iron rollers for condensing the several ribands, and a wooden pin round which the ribands .ire lapped, resting between two leather-covered rollers, one of which receives motion from mill gearing, and imparls it by friction to the lap roller over it. The iron ends of the lap roller lie in upright slots, which allow them freedom to rise as the roller gets filled with fleece. The two pairs of rollers at o effect the extension of the card-end, and reduce its size. The under rollers are made of iron and fluted ; the upper ones are also made of iron, but they are covered with a coat of leather, nicely glued on over a coat of flannel, which two coats render them both smooth and elastic. Two weights, w, press the upper cylin- ders steadily down upon the under ones. Between the first and second pair there is a certain interval, which should be proportioned to the length of the cotton staple. The second, or that furthest from the funnel, revolves with greater velocity than the first, and therefore turns out a greater length of riband than it receives from its fellow ; the con- sequence is a corresponding extension of the riband in the interval between the two pairs of rollers. The motions of the several parts of the engine are effected in the following way. The band, p p, fig. 397, which comes down from the pulley upon the main shaft near the ceiling of the work-room, drives, by means of the pulley q, the drum/,^g. 396, with a velocity of from 130 to 140 revolutions in a minute. From another pulley r, on the axis of the drum, the axis of t is driven by the band s working round the pulley / on its end. This shaft drives the crank and lever mechanism of the stripper knife i. A third pulley of the same size as r is fixed just within the frame to the other end of the drum, and from it a crossed or close band r' goes to a pulley upon the small runner h', to give this its rapid rotation. Upon the opposite end of the engine in fig. 396, these wheels and pulleys are marked with dotted lines. Here we may observe, first, a pulley y upon the drum, and a pulley a', which receives motion from it by means of the band «. The axis of a' carries in front a pinion m', which sets in motion the wheel n'. The latter imparts mo- tion, by means of a pinion and intermediate wheel o', to the wheel h on the doffer cylinder, and consequently to that cylinder on the one hand ; and it turns, by the carrier wheel p\ a wheel x, whose axis is marked also with x in fig. 396, upon the other hand. The axis of x', fig. 396, carries, towards the middle of the engine, a very broad wheel, which is represented by a small dotted circle. The toothed wheel v of the smooth '•oiler v\fig. 396, and the two toothed wheels o o, fig, 396, of the under rollers o o, fig, 396, work into that broad wheel. The wheel of the second or delivery fluted roller is seen to be smaller than that of the first, by which means the difference of their velocities IS obtained. The large runner t is driven from the main drum pulley, by means of the band s', and the pulley m', fig. 396. The said band is crossed twice, and is kept in ten- sion by the pulley f, round which it passes. The motion of the fluted rollers e, which feed in the cotton fleece, is effected by means of a bevel wheel b' on the end of the doffer, which works into a similar wheel c' on the oblique axis d' (dotted lines across the drum), of the pinion e' upon the lower end of the same axis which turns the wheel/*, upon the under feed roller. Each of the feed rollers, ^g. 397, bears a pinion « e at one end, so that the upper roUex turns round with the under one. The roller b,fig. 396, is set in motion by means of 33 1 i s ! 512 COTTON MANUFACTURE. its wheel a:'; which is driven by a wheel r' on the other end of the under feed roncr, through the intervention of the large carrier wheel w'. The original or fir.t motion of 6 must be as quick as that of the fluted feed rollers «, m order that the former may uncoil as much lap as the latter can pass on. ' The annexed table exhibits the proper velocities of the different cylinders and rollers of the carding engine, which, however, are not invariable, but may be modified according to circumstances, by changing the pinions e',/tg. 396, and w', according to the quality or length oi the coiton staple. Ihe velocities stated in the table will be obtained when the pulley a , Jig, 396, is made greater than y in the proportion of 3 to 2, and the wheels and pinions have the following number of teeth : m', 18; «', 50; its pinion, 18; A, 128: ^\f^ ' J?^ *l'°**^ 7^.^^^ "P*''' ^^^ ^^*^^ *^^ ^' 37 teeth ; the wheel o of the first fluted roller, 3o; that of the second, 21 ; r, 44 ; 6' and e', 54 ; €', 10 ; f, 63 Names of the parts. Drum / - DofferA Runner or urchin i' - Ditto A' - - - Fluted feed roller e - First drawing roller o - Second ditto Smooth delivery roller v Diameter in inches. 35 14 •25 ■5 •167 167 2-5 Circumference in inches. 109-9 43-96 19-62 11- 3-664 3-14 3-664 7-85 Revolationain one minute. 130 4-38 5- 470- 0-696 68-71 114-52 54-66 Velocity. 142-87 192-5 98-1 5170- 2-55 215-75 419-6 429-08 The operauon of the runners, h' and i', becomes very plain on comparing their ^peed with one another and with that of the main-drum, and taking into account the direction of the card teeth. The cotton wool, taken off from the feed-rollers by the drum is caught by the opposite teeth of the large runner i', which, on account of its slower sir- face rotation (98 inches per minute), may be considered to be at rest with reference to the drum, and therefore, by holding the cotton in its teeth, wUl commence its cardin*' The small runner A, in consequence of its greater surface velocity (5170 inches per minuie\ will comb the cotton-wool back out of the teeth of the large runner, but it will give it up in Its turn to the swifter teeth of the drum, which, in carrying it forwards, encoun- ters the teeth of the top cards, and delivers up the filaments to their keeping for some time. We thus see how essential the runners are to the perfection as well al to the ac- celeration of the carding process for ordinary cotton wool, though for the slenderer and .onger filaments of the sea-island kind they are not so well adapted. In cleaning' the carding-engmes the httle runner must be looked to every time that the drum is examined. The large runner and the doffer require to be cleaned together. The quantity of cotton spread upon the feed^iloth, the velocity of it, and of the drawing-rollers, must all be carefully adjusted to the grist of the yam intended to be spun. Suppose the sizes and velocities to be as represented in the preceding table, that the engine is a double card 36 inches broad, and that it is furnished with a lap from the lan- machme of which 30 feet in length weigh 5 lbs. In one minute the surface of the feedl rollers e, passes 255 inches of that lap onwards; in the same time the main-drum wUI work It ofl. To card the whole 30 feet, therefore, 141 minutes, or 2 hours and 21 minutes wiUbe required. In this time the circumference of the rollers, « r, moves throueh a space of 141X42,908 in =5042 ft., and delivers a card-end of thatTngth,w^^^^^^ ?079*'f.Tr r' ''"^- ^""'T^'^f' Ihat is, 4 lbs. 1 1| oz. One pound will form a riband .v-Jlr Vr^' t^'"?' ^T:?^"? ^° ^\^ English mode of counting, about number |, or Ml T ^J-T'T ^/ ^}^^ cotton-fleece to this degree proceeds as follows :-In the 141 minutes which the feed-rollers take to introduce the 30 feet of lap, the dotferT makes 617-08 revolutions and the comb, or doffer knife, t, detaches from Ve doffer te'eth a thm fleecy web of 2262 feet in length. The first' drawing pair of fluted rollers, by its quick motion, with the aid of the funnel, wj, converts this fleece into a riband 2535 feet long. The second pair of the fluted rollers ex- tends this riband to 4390 feet, since their sur- face velocity is greater than the first pair in that proportion. The slight elongation (of only 112 feet, or about -I- ) which takes place between the delivery fluted rollers and the smooth cylin- ders, Vy tt, serves merely to keep the card-end steadily upon the stretch without folding. Fig, 398 is a plan of the card and the fleece, where h is the cylinder, n is the funnel, u the pressing rollers, and A' the card-ends in the can. COTTON MANUFACTURJ:. 513 Fig», 399, 400, represent skeletons of the old cards to facilitate the comprehens'.on of these complex machines. Fig, 399 is a plan ; f is the main drum ; m m is the doffef knife or comb ; g the carded fleece hemmed in by the funnel a, pressed between the roll* ers 6, and then falling in narrow fillets into its can. Fig. 400, k l are the feed rollers; A B the card drum ; c d the lops ; e f the doffer card ; m k the doffer knife ; d- 6, c, the card-end passing between compressing rollers into the can a. The drawing and doubling are the next operation. The ends, as they come from the cards, are exceedingly tender and loose, but the filaments of the cotton are not as yet laid 80 parallel with each other as they need to be for machine spinning. Before any degree of torsion therefore be communicated, a previous process is required to give the filaments a level arrangement in the ribands. The drawing out and doubling accomplish this pur- pose, and in a manner equally simple and certain. The means employed are drawing- rollers, whose construction must here be fnlly explained, as it is employed in all the fol- lowing machines ; one example of their use occurred, indeed, in treating of the cards. Let a and 6, fig. 401, represent the section of two rollers lying over each other, which touch with a regulated pressure, and turn in contact upon their axes, in the direction shown by the arrows. These rollers will lay hold of the fleecy riband presented to them at a, draw it through between them, and deliver it quite unchanged. The length of the piece passed through in a given time will be equal to the space which a point upon the circumference of the roller would have percured in the same time ; that is, equal to the periphery of one of the rollers multiplied by the number of its en- tire revolutions. The same thing holds with regard to the trans- mission of the riband through between a second pair of rollers, c, rf, and a third, e,f. Thus the said riband issues from the third pair exactly the same as if entered at a, provided the surface speed of all the rollers be the same. But if the surface speed of c and d be greater than that of a and 6, then the first-named pair will deliver a greater length of riband than the last receives and transmits to it. The conse- quence can be nothing else in these circumstances than a regulated drawing or elonga- tion of the riband in the interval betwixt a, 6, and c, d, and a condensation of the fila- ments as they glide over each other, to assume a straight parallel direction. In like manner the drawing may be repeated by giving the rollers, e,f, a greater surface speed than that of the rollers, c and d. This increase of velocity may be produced, either by enlarging the diameter, or by increasing the number of turns in the same lime, or finally by both methods conjoined. In general the drawing-machine is so adjusted, that the chief elongation takes place between the second and third pair of rollers, while that between the first and second is but slight and preparatory. It is obvious, besides, that the speed of the middle pair of rollers can have no influence upon the amount of the extension, provided the speed of the first and third pair remains unchanged. The roll- ers, flf, b, and c, d, maintain towards each other continually the same position, but they may be removed with their frame-work, more or less, from the third pair, e,f, according as the length of the cotton staple may require. The distance of the middle point from 6 and d, or its line of contact with the upper roller, is, once for all, so calculated, that it shall exceed the length of the cotton filaments, and thereby that these filaments are never in danger of being lorn asunder by the second pair pulling them while the first holds them fast. Between d and/, where the greatest extension lakes place, the distance must be as small as it can be without risk of tearin? them in that way ; for thus will the uni- formity of the drawing be promoted. If the distance between d and / be very ereat, a riband passing through will become thinner, or perhaps break in the middle; whe.ix,e we see that the drawing is more equable, the shorter is the portion submitted to extension at a time, and the nearer the rollers are to each other, supposing Jiem always distant enough not to tear the staple. 514 COTTON MANUFACTURE. The under rollers, 6 rf/, are made of iron, and, to enable them to lay firmer hold of th« filaments, their surfaces are fluted with triangular channels parallel to their axes. Th« upper rollers, a c e, are also made of iron, but they are smooth, and covered with a dou- ble coating, which gives them a certain degree of softness and elasticity. A coat of flannel is first applied by sewing or glueing the ends, and then a coat of leather in the same way. The junction edges of the leather are cut slanting, so that when joined by the glue (made of isinglass dissolved in ale) the surface of the roller may be smoothly cylindrical. The top rollers are sometimes called the pressersy because they press by means of weights upon the under ones. These weights are suspended to the slight rods k k' ; of which the former operates on the roller e alone, the latter on the two rollers a and e together. For this purpose the former is hung to a c shaped curve t, whose upper hook embraces the roller e ; the latter to a brass saddle A, which rests upon a and c. A bar of hard wood, g, whose under surface is covered with flannel, rests, with merely its own weight, upon the top roller, and strips off" all the loose hanging filaments. Similar bars with the same view are made to bear up under the fluted rollers 6 d /, and press against them by a weight acting through a cord passing over a pulley. Instead of the upper dust-covers, light wooden rollers covered with flannel are occasionally applied. Were the drawing of a riband continued till all its fibres acquired the desired degree of parallelism, it would be apt, from excessive attenuation, to tear across, and thereby to defeat the purpose of the spinner. This dilemma is got rid of in a very simple way, namely, by laying several ribands together at every repetition of the process, and incor- porating them by the pressure of the rollers. This practice is called doubling. It is an exact imitation of what takes place when we draw a tuft of cotton wool between our fingers and thumb in order to ascertain the length of the staple, and replace the drawn filaments over each other, and thus draw them forth again and again, till they are all parallel and of nearly equal length. The doubling has another advantage, that of causing the inequalities of thickness in the ribands to disappear, by applying their thicker to theix thinner portions, and thereby producing uniformity of substance. 402 ^ 11 The drawing frame, as shown in section in figs. 401, 403, and in a back view in fig, 402, will require, after the above details, little further explanation. / / are the weights which press down the top rollers upon the under ones, by means of the rods k k' and hook t. Each fluted roller is, as shown at/, ^g. 402, provided in the middle of its length with a thinner smooth part called the neck, whereby it is really divided into two fluted portions, represented by c e in the figure. Upon this middle neck in the pressure rollers, the hook t and the saddle h immediately bear, as shown in the former ^ig. 401. The card-ends, to the number probably of six, are introduced to the drawing frame either from tin cans, placed at e e,fig. 403, and at a, fig. 402, or from lap-bobbins ; and, after passing through it, the ribands or slivers are received either into similar tin cans, as g, or upon other lap- bobbins upon the other side. These appendages may be readily conceived, and are therefore not exhibited in all the drawings. Three of the slivers being laid together are again intro- duced to the one fluted portion a b,fig. 401, and three other slivers to the other portion* The sloping curved tin or brass plate s, fig. 402, with its guide pins /, serves to conduct the slivers to the rollers. When the two threefold slivers have passed through between the three pairs of rollers, and been thereby properly drawn, they run towards each other in aq cUique direction, behind the last roller pair e f,fig. 401, and unite, on issuing through tbt COTTON MANUFACTURE. 515 eonical funnel m, yig. 402, into a single riband or spongy sliver ; which is immeJiatel> carried olf with equable velocity by two smooth cast-iron rollers, n o,figs. 402 and 403, and either dropped into a can, or wound upon a large bobbin. The surface speed of these rollers is made a trifle greater than that of the delivery drawing rollers, in order to keep the portion of sliver between them always in an extended state. Four fluted draw- ing portions are usually mounted in one drawing frame, which are set a-going or at rest together. To save all unnecessary carrying of the cans from the back to the front of the frame, the drawing heads are so placed, that the first and third discharge their slivers at the one side, and the second and fourth at the other. By this arrangement, the cans filled behind one head, are directly pushed aside in front of the next drawing head ; by which alternate distribution the work goes on without interruption. The fast pulley u^fig. 403, by which the whole machine is driven, derives its motion from the main shaft of the mill by means of the band w. The similar pulley z, which sits loose upon the axis, and turns independently of it, is called the loose pulley ; both together being technically styled riggers. "When the operative desires to stop the ma- chine, he transfers the band from the fast to the loose pulley by means of a lever, bearing a fork at its end, which embraces the band. Upon y, four pulleys such as x are fixed, each of which sets in motion a drawing head, by means of a band like w going round the pulleys x and ft. On account of the inverted position of the heads, which requires the motion of u to be inverted, the bands of the first and third heads are open, but those of the second and fourth are crossed. Every head is provided with a loose pulley r, as well as the fast pulley u, in order to make the one stop or move without affecting the others. The shaft of the pulley « is the prolonged shaft of the backmost fluted roller /. It car- ries besides a small pulley q, which, by means of the band r, and the pulley p^fig. 402, sets in motion the undermost condensing roller o. The upper roller n presses with its whole weight upon it, and therefore turns by friction. The toothed wheel-work, by which the motions are communicated from the backmost fluted roller to the middle and front ones, is seen in^g. 403. The wheel /,/g. 401, of 20 teeth, works in a 44-toothed carrier-wheel, on whose axis there are two smaller wheels; 2 with 26 teeth, and 1 with 22 teeth. The wheel d, fig. 403 of the middle roller, and the wheel h of the front roller, are set in motion by other carrier wheels ; the first has 27 teeth, and the last 40. For every revolution of 6, the roller d makes nearly If turns, and the roller / 4 revolutions. The top rollers revolve, as we have stated, simply by the friction of contact with the lower ones. Now suppose the diameter of the rollers h and d to be 1 inch or 12 lines, that of/ \\ inches or 15 lines, the surface velocities of the three pairs of rollers in the series will be as 1, If, and 5. Every inch of the cotton sliver will be therefore extended between the first and second pairs of rollers into If inches, and between the second and third or delivery pair into 6 inches ; and after the sliver has passed through all the four drawing heads, its length will be increased 625 times =r 5 X 5 X 5 X 5- The further the drawing process is pushed, the more perfectly will its object be ac- complished, namely, the parallelism of the filaments. The fineness of the appearance of the sliver after the last draught depends upon the number of doublings conjointly with the original fineness and number of drawings. The degree of extension may be increased or diminished, by changing the wheels in fig. 403, for others with a diflferent number of teeth. Thus the grist or fineness of the sliver may be modified in any desired degree ; for, when the subsequent processes of the mill remain the same, the finer the drawings the finer will be the yarn. For spinning coarse numbers or low counts, for example, six card-ends are usually transmitted through the first drawing head, and con- verted into one riband. Six such ribands again form one in the second draught ; six of these again go together into the third sliver ; and this sliver passes five-fold through the last draught. By this combination 1080 of the original card-ends are united in the finished drawn sliver =6 X 6 X 6 X 5. The fineness of the sliver Is, however, in conse- quence of these doublings, not increased, but rather diminished. For, by the drawing, the card-end has been made 625 times longer, and so much smaller ; by the doubling alone it would have become 1080 times thicker ; therefore, the original grist is to the i resent as 1 to the fraction t^^tt 5 ^^^^ is, supposing 1072 feet of the riband delivered by the card to weigh one pound, 625 feet, the sliver of the last drawing, will also weigh a pound, which corresponds in fineness to number 0*24, or nearly \. The'rearmost or last drawing roller has a circumference of nearly 4 inches, and makes about 150 revolutions per minute; hence, each of these drawing heads may turn off 35,000 feet of sliver in 12 hours. Some manufacturers have lately introduced a double roller beam, and a double draught at the same doubling, into their drawing frames. I have seen this contrivance working satisfactorily in mills where low counts were spun, and where the tube roving frame was employed ; but I was informed oy competent judges, that it was not advisable where a level yam was required for good printing calicoes 1 I' 516 COTTON MANUFACTURE. The loss which the cotton suffers in the drawing frame is quite inconsiderable. It consists of those filaments which remain upon the drawing rollers, and collect, in a great measure, upon the flannel facing of the top and bottom cleaner bars. It is thrown among the lop cleanings of the carding engine. When from some defect in the rollers, or negligence in piecing the running slivers, remarkably irregular portions occur in the%ibands, these must be torn off, and returned to the lap machine to be carded anew. The fiAh operation may be called the first spinning process, as in it the cotton sliver receives a twist ; whether the twist be permanent, as in the bobbin and fly frame, or be undone immediately, as in the tube-roving machine. In fact, the elongated slivers of parallel filaments could bear little further extension without breaking asunder, unless the precaution were taken to condense the filaments by a slight convolution, and at the same time to entwine them together. The twisting should positively go no further than to fulfil the purpose of giving cohesion, otherwise it would place an obstacle in the way of the future attenuation into level thread. The combination of drawing and twisting is what mainly characterizes the spinning processes, and with this fifth operation, therefore, commences the formation of yarn. As, however, a sudden extension to the wished-for fineness is not practicable, the draught is thrice repeated in machine spinning, and after each draught a new portion of torsion is given to the yarn, till at last it possesses the degree of fineness and twist proportioned to its use. The prelimmary spinnmg process is called roving. At first the torsion is slight in Oronortion to the extension, since the solidity of the still coarse sliver needs that cohesive aid only in a small degree, and looseness of texture must be maintained to facilitate to the utmost the further elongation. Fig. 404 is a section of the can rovinf frame, the ingenious invention of Ark Wright, which, till within these 14 years> was the principal machine for communi eating the incipient torsion to the spongi cord furnished by the drawing heads. Ir differs from that frame in nothing bni the twisting mechanism ; and consists oi two pairs of drawing rollers, a and b, be tween which the sliver is extended in the usual way ; c are brushes for cleaning th^ rollers ; and d is the weight which presses the upper set upon the lower. The wiping covers (not shown here) rest upon a b. The surface speed of the posterior or second pair of rollers is 3, 4, or 5 times greatei than that of the front or receiving pair, according to the desired degree of attenua* tion. Two drawn slivers were generally united into one by this machine, as is shown is the figure, where they are seen coming from the two cans e e, to be brought together by the pressure rollers, before they reach the drawing rollers a b. The sliver, as it escape? from these rollers, is conducted into the revolving conical lantern g, through the funnel / at its top. This lantern-can receives its motion by means of a cord passing over a pulley fe, placed a little way above the step on which it turns. The motion is steadied by the collet of the funnel /, being embraced by a brass busk. Such a machine gene- rally contained four drawing heads, each mounted with two lanterns; in whose side there was a door for taking out the conical coil of roving. The motion imparted to the back roller by the band pulley or rigger m, was conveyed to the front one by toothed wheel work. The vertical guide pulley at bottom, n, served to lead the driving band descending from the top of the frame round the horizontal whorl or pulley upon the under end of the lantern. The operation of this can-frame was pleasing to behold ; as the centrifugal force served both to distribute the soft cord in a regular coU, and also to condense a great deal of it most gently within a moderate space. Whenever the lantern was filled, the tenter carried the roving to a simple machine, where it was wound upon bobbins by hand. Notwithstanding every care in this transfer, the delicate texture was verj' apt to be seriously injured, so as to cause corresponding injuries in every subsequent operation, mnd in the finished yarn. Messrs. Cocker and Higgins, of Salford, had the singular merit, as I have said, of superseding that beautiful but defective mechanism, which had held a prominent place in all cotton mills from almost the infancy of the factory system, by the following apparatus. The Bobbin and Fly frame is now the great roving machine of the cotton manufa^ COTTON MANUFACTURE. !^n tore ; to which may be added, for coarse spinning, the tube roving frame. Of such « complicated machine as the bobbin and fly frame, it is not possible to give an ade- quately detailed description in the space due to the subject in this Dictionary. Its mechanical com- binations are, however, so admira- ble as to require such an account as will make its functions inteUi- gible by the general reader. Fig. 405 exhibits a back view oi" this machine ; and fig. 406 a sec- tion of some of the parts not very visible in the former figure. The back of the machine is the side at which the cotton is introduced be- tween the drawing rollers. The cans, or lap-bobbins filled with slivers at the drawing frame, are placed in the situation marked B, fig. 406, in rows parallel with the length of the machine. The sliver of each can, or the united slivers of two contiguous cans, arc conducted upwards along the sur face of a sloping board f, and through an iron staple or guide e, betwixt the usual triple pair of drawing rollers, the fiirst of which is indicated by a, b. In fig. 405, for the purpose of simplifying the figure, the greater part of these rollers and their subordinate parts are omitted. After the slivers have been sufficiently extended and attenuated between the rollers, they proceed forwards, towards the spindles 1 1 1, where they receive the iwist, and are wound upon the bobbins h. The machine deline ated contains thirty spindles, but many bobbin and fly frames con- tain double or even four times that number. Only a few of the spin dies are shown in^g. 405, for feai of confu.sing the drawing. With regard to the drawing functions of this machine, I have already given abundanJ 518 COTTON MANUFACTURE. explanation, so far as the properties and operation of the rollers are concerned. The frame-work of this part of the machine, called the rolUr^am, is a cast-iron bench npo» which nine bearers, c, are mounted for carrying the rollers. The fluted rollers aaa fig, 407, are constructed in four pieces for the whole length, which are parted from each other by tliinner smooth cylindric portions, z, called necks. Seven such partings for four rollers, and one parting for two rollers, constitute together the 30 fluted rollers of which the whole series consists. The coupling of these roller subdivisions into one cylinder, is secured by the square holes x, and square pins y,fig. 407, which fit into the holes "of the adjoining subdivision. The top or pressure rollers b, are two-fold over the whole set; and the weighted saddle presses upon the neck tr, which connects * .no rrv . ^ ^^^^y P^'""* ^s ^^^'s already explained under fig,W2. These weights g g,yig.406, are applied in this as in the drawing frame ; d are the bars faced with flannel for cleaning the top rollers. A similar bar is applied beneath the rollers, to keep the flutings clean. The structure and operation of the spindles t may be best understood by examining the section Jig. 408. They are made of iron, are cylindrical from the top down to a2, but from this part down to the steel tipped rounded points they are conical. Upon this conical portion there is a pulley k, furnished with two grooves in its circumference, in which the cord runs that causes the spindle to revolve. The wooden bobbin h ia slid upon the cylindrical part, which must move freely upon it, as will be presently explained. To the bobbin another two-grooved pulley or whorl g is made fast by means of a pin r, which passes through it ; by removing this pin, the bobbin can be instantly taken oflT the spindle. The upper end of the spindle bears a fork s t, which may be taken ofl" at pleasure by means of its lefl-handed screw ; this fork, or flier, has a funnel-formed hole at r. One arm of the fork is a tube, .v, u, open at top and bottom ; the leg, t, is added merely as a counterpoise to the other. In fig. 406, for the sake of clearness, the forks or fliers of the two spindles here repre- sented are left out ; and in fig. 405, only one is portrayed for the same reason. It is likewise manifest from a comparison of these two figures that the spindles are alternately placed in two rows, so that each spindle of the back range stands opposite the interval between two in the front range. The object of this distribution is economy of space, as the machine would need to be greatly longer if the spindles stood all in one line. If we suppose the spindles and the bobbins (both of which have independent motions) to revolve simultaneously and in the same direction, their operation will be as follows: The sliver, properly drawn by the fluted rollers, enters the opening of the funnel v, proceeds thence downwards through the hole in the arm of the fork, runs along its tube «, *, and then winds round the bobbin. This path is marked, in fig. 408, by a dot- ted line. The revolution of the spindles in the above circumstances effects the twisting of the Oliver into a soft cord; and the flier s, ty or particularly its tubular arm s, lavs this cord upon the bobbin. Were the speed of the bobbins equal to that of the spindles, that is, did the bobbin and spindle make the same number of turns in the same lime, the pro- cess would be limited to mere twisting. But the bobbin anticipates the fliers a little, that is, it makes in a given time a somewhat greater number of revolutions than the spindle, and thereby effects the continuous winding of the cord upon itself. Suppose the bobbin to make 40 revolutions, while the spindle completes only 30 ; 30 of these revo- lutions of the bobbin will be inoperative towards the winding-on, because the fliers fol- low at that rate, so that the cord or twisted sliver will only be coiled 10 times round the bobbin, and the result as to the winding-on will be the same as if the spindle had stood still, and the bobbin had made 40 — 30 = 10 turns. The 30 turns of the spindles serve, therefore, merely the purpose of communicating twist. The mounting and operation of the spindles are obvious-.y the same as they are upon the household flax wheel. In the bobbin and fly frame there are some circumstances which render the construction and the winding-on somewhat difficult, and the mechanism not a little complicated. It may be remarked, in the first place, that as the cord is wound on, the diameter of the bobbin increases very rapidly, and therefore every turn made round it causes a greater length of rovins to be taken up in succession. Were the motions of the bobbins to continue unchanged in this predicament, the increased Telocity of the winding-on would require an increased degree of extension, or it wouU COTTON MANUFACTURE. 519 occasion the rupture of the cord, because the front fluted rollers move with uniform speed, and therefore deliver always the same length of sliver in the same time. ,It is therefore necessary to diminish the velocity of the bobbins, or the number of their turns, in the same proportion as their diameter increases, in order that the primary velocity may remain unchanged. Moreover, it is requisite for the proper distribution of the cord upon the bobbin, and the regular increase of its diameter, that two of its •uccessive convolutions should not be applied over each other, but that they should be laid close side by side. This object is attained by the up and down sliding motion of the bobbin upon the spindle, to the same extent as the length of the bobbin barrel. This up and down motion must become progressively slower, since it increases the diameter of the bobbin at each range, by a quantity equal to the diameter of the sliver. What has now been stated generally, will become more intelligible by an example. Let it be assumed that the drawing rollers deliver, in 10 seconds, 45 inches of roving, and that this length receives 30 twists. The spindles must, in consequence, make 30 revolutions in 10 seconds, and the bobbins must turn with such speed, that they wind up the 45 inches in 10 seconds. The diameter of the bobbin barrels being Ij^ inches, their circumference of course 4^ inches, they must make 10 revolution^more in the same lime than the spindles. The effective speed of the bobbins will be thus 30-|-10=:40 turns in 10 seconds. Should the bobbins increase to 3 inches diameter, by the winding-on of the sliver, they will take up 9 inches at each turn, and con- sequently 45 inches in 5 turns. Their speed should therefore be reduced to 30-[-5=35 turns in 10 seconds. In general, the excess in number of revolutions, which the bobbins must make over the spindles, is inversely as the diameter of the bobbins. The speed of the bobbins must remain uniform during the period of one ascent or descent upon the spindle, and must diminish at the instant of changing the direction of their up and down motion ; because a fresh range of convolutions then begins with a greater diameter. When, for example, 30 coils of the sliver or roove are laid in one length of the bobbin barrel, the bobbin must complete its vertical movement up or down, within 30 seconds in the first case above mentioned, and within 60 seconds in the second case. The motions of the drawing rollers, the spindles, and bobbins, are produced in the following manner : — A shaft c', figs. 405 and 406, extending the whole length of the machine, and mounted with a fly wheel d', is set in motion by a band from the running pulley upon the shaft of the mill, which actuates the pulley a', b' is the loose pulley upon which the band is shifted when the machine is set at rest. Within the pulley a', but on the outside of the frame, the shaft c' carries a toothed wheel bi with 50 teeth, which by means of the intermediate wheel c2 turns the wheel d'2 upon the prolonged shaft of the backmost fluted roller (m2, fig. 406.) This wheel rfs has usually 54 teeth ; but it may be changed when the roove is to receive more or less twist ; for as the spindles revolve with uniform velocity, they communicate the more torsion the less length of sliver is delivered by the rollers in a given time. Upon the same shaft with di, a pinion d of 32 teeth is fixed, which works in a wheel /a of 72 teeth. Within the frame a change pinion g2 is made fast to the shaft of /2. This pinion, which has usually from 24 to 28 teeth, regulates the drawing, and thereby the fineness or number of the roving. It works in a 48-toothed wheel hi upon the end of the backmost fluted roller a^fig. 406. The other extremity of the same roller, or, properly speaking, line of rollers, carries a pinion Za, furnished with 26 teeth, which, by means of the broad intermediate wheel fea, sets in motion the pinion t's of 22 teeth upon the middle roller. When the diameter of all the drawing rollers is the same, suppose 1 inch, their propor- tional velocities will be, with the above number of teeth in the wheel work, if g2 have 24 teeth, as 1 : MS :4-5; and the drawn sliver will have 4| times its original length. The front or delivery roller of the drawing frame is of late years usually made 1 J or 1| inches in diameter. If 625 feet of the sliver from the drawing frame weighed one pound, 2790 feet of the roving will now go to this weight, and the number will be M2; that is, 1 hank and 12 hundredths to the pound. The front pair of fluted rollers makes about 90 revolutions, and deliver? 282-6 inches of roving in the minute, when of one inch diameter. The spindles i (figs. 405 and 406), rest, with their lower ends, in steps 7, which are fixed in an immoveable beam or bar m. To protect it from dust and cotton filaments, this beam is furnished with a wooden cover n, in which there are small holes for the passage of the spindles right over the steps. In fig. 405, two of the eight covers «, which compose the whole range wi, are removed to let the steps be seen. The cylindrical part of each spindle passes through a brass ring o ; and all these 30 rings, whose centres must be vertically over the steps /, are made fast to the copping beam p. This beam is so called, because it is destined not merely to keep the spindles upri?ht by the rings attached to it, but, at the same time, to raise and lower along the spindles the bobbins 520 Iff COTTON MANUFACTURE. COTTON MANUFACTURE. 521 \M m Which rest on these rings; for which puriKJse the two racks, or toothed bars mt nA made fast to it, are designed, as will be presently explained. To effect the revolution of the spindles, there are attached to the main shaft c' two whorls or pulleys e'f each bearing four grooves of equal diameter. Each of these pullevs puts one half oV the spindles in motion, by means of a cord, which, after going round the whorls k turns four times about the pulleys of the shaft c'. Two guide pulleys h', each four-grooved and two others t', with a single groove, which turn independently of the others upon the above shaft, serve to give the whorl cords the proper direction, as well as to' keep them tight. The spindles revolve 200 times or thereby in the minute ; and therefore impart two turns or twists to every three inches of the roving. The revolution of the bobbins is independent of that of the spindles, althou«»h it like- wise proceeds from the shaft c', and differs from it in being a continually retarded motion. The simplest method of effecting this motion, is by means of the wooden or Un plate cone &', which revolves equaDy with the shaft c', and at the same time slides along It. The manner in which this operates is shown in section in Jig. 409. Here we per- ceive the rod 52, which extends from the base toward the narrow end of the truncated eone, dhd pi a forked bearer or carrier made fast to the shaft c by a screw, which compels the cone, by means of that rod, to obey the movements of c'. In the large end Of the cone there is an aperture, throush which the bearer can be ?ot at. The smaller end carries outside a projection 02, provided with a groove, which is embraced by the ^rked end of a rod q'.fig. 410, that serves to shove the cone alon? upon the sh^ C Directly under the cone, there is an upright round pillar p\ upon which the holder ff of the two guide pulleys r is adjustable. A bar r 2 placed along-side of the holder prevents \\% turning round, but allows it to slide along p' by friction. The weight of the holder and the pulley is sufficient to distend the endless band n', which runs from the cone fe , ihrou-h under the pulley /', and round the small drum m' on the shaft «2 A pulley or whorl t% with four grooves, is made fast by means of a tube to this shaft' and slides along it backwards and forwards, without ever ceasing to follow its revolutions. lh€ Shalt possesses for this purpose a long fork, and the interior of the tube a corre- sponuing tongue or catch. There is besides upon the tube beneath the pulley, at tn, a groove that goes round it, m which the staple or forked end of an arm like rfl, fie. 410. made fast to the copp.ng beam p, catches. By the up and down movement of that beam, the pulley 1 2 takes along with it the arm that embraces the tube, which therefore rises and falls equally with the bobbins h', and their pulleys or whorls a. This is requisite, smce the bobbms are made to revolve by the pulleys 1 2, by means of two endless cords or bands. ' ' ^-^ui^^m «rTi^^i?S- ^"^."^^^^ y^'\f the mechanism is the adjustment, by which the revolution of the bobbins is continualy retarded, and their up and down, or copping motion, along he spindles, IS also retarded in like proportion. The vertical pulley /' (towards the left end of the shaft c) has at its right side a somewhat larger disc or sheave g-, with a perfect y uniform, but not a very smooth surface. Upon this sheave, a smaller horizontal pulley x rubs, whose upper face is covered with leather to increase the friction The under end of the shaft y% of the pulley x^ turns in a step, which is so connected with tte arm t, of the large bent lever /' r', that it always stands horizontally, whatever direction the arms of that lever may assume. The shaft yi is steadied at top by aa annular holder or bush, which embraces the fast arm xZ with its forked end. Upon iU opposite side, this arm carries a pulley y2, upon which a cord goes, that is made fast to the holder of the shaft y\ and loaded with the weight z\ The weight presses the pulley x' against the surface of g', in such wise as to effect the degree of friction necessary in order that the revolution of g^ may produce an uninterrupted revolution in x'. ^ A pinion u'', whose length must be equal at least to the semi-diameter of the sheave g', is placed upon the under end of the shaft yi. It has 22 teeth, and takes into a 62-toothed horizontal wheel z2. Upon the upper end of this wheel the conical pinion a3 is made fast which may be changed for changing the speed, but usually has from 28 to 30 teeth. By this pinion the conical wheel 63 is turned, which has 30 teeth, and whose shaft is c3. This shaft carries upon its opposite end a six-leaved pinion, d3, which takes into the calender wheel /3, formed with cogs like a trundle, upon the long shaft e3. In fig, 411 the wheel p is exhibited with its pinion ds. Here we may remark, that in the circum- ference of the wheel there is a vacant place, ^3, void of teeth. When, by the motion of the wheel, the pinion comes opposite to this opening, it turns round about the last tooth of the wheel, falls into the inside of the toothed circle innrked by the dotted lines, and thus gives now an inverse movement to the wheel /3, while itself revolves always in the tame direction. This reversed motion continues tiU the opening g3 comes once more CE 412 1— ^ K \5h. opposite to the pinion, when this turns round about the last tooth of that side, and begins again to work in the exterior teeth. Thus, by the uniform motion of ds and its dependant parts, the wheel p, with its shaft e3, revolves alternately to the right hand and the left. That this result may ensue, the shaft c3 of the pinion must be able to slide endwise, without losing its hold of a3 and 63. This adjustment is effected by placing the end of the said shaft, nearest 63, in a box or holder t3, in which it can turn, and which forms a vertical tube to this box, as a downward prolongation which is fixed to the tail of the conical pinion a\ Fig, 412 shows this construction in section upon an enlarged scale. The second bearer of the shaft nearest rf3, must possess likewise the means of lateral motion. When therefore the pinion d3 shifts through the opening of the wheel /3 outwards or inwards, its shaft c3, makes a corresponding small angular motion upon the pivot of a3, by means of the tube i3 ; a3 and 63 remain thereby com- pletely in gear with one another. The above-described alternate revolutions of the wheel /3 serve to produce the up and down motions of the bobbins. The shaft 63 has for this purp^/Se two pinions n* n«, -which work in the rack teeth m^ ms of the copping rail p, and thus alternately raise and sink it with the bobbins which rest upon it. The weight of the copping beam and all its dependant parts, is poised by two counterweights m*, whose cords run over the pulleys 04 04 04, fig, 405, and have their ends made fast to the frame, so as to make the upward motion as easy as the downward. The two upper pulleys out of the three of each weight are fixed to the frame; the under one, round which the cord first runs, is attached to the cooping beam, rising and falling along with it. As long as the friction disc x' remains at the same height, the pulley g' derives its motion from the same circle of the said disc, and the up and down motion of the copping beam is also uniform. But when that disc ascends so as to describe with its edge a small circle upon the face of g', its motion must become proportionally more slow. This is the method, or principle of retarding the copping motions of the bobbins. It has been shown, however, that the rotation of the bobbins should be also retarded in a progressive manner. This object is effected by means of the cone k', which, as the band n progressively approaches towards its smaller diameter, drives the pulleys or whorls q of the bobbins with decreasing speed, though itself moves uniformly quick with the shaft c. To effect this variation, the cone is shifted lengthwise along its shaft, while the band running upon it remains continually in the same vertical plane, and is kept distended by the weight of the pulley 0'. The following mechanism serves to shift the cone, which may be best understood by the aid of the figures 413, 414, and 410. A long cast iron bar in*. 522 COTTON MANUFACTURE. If which hears two horizontal projecting poppets, o3o3, is made fast to the front nprigh face of the copping beam a. Through the above puppets a cylindrical rod n3 passes freely 413 <*!*# ' i rfr-t^ ^ ^^O^ ^ m & which is left out in Jig. 410, that the parts lying behind it may he better seen. Upon this rod there is a kmd of fork, p3p3, to which the alternating rack bars o3 are made fast. The teeth of these racks are at unequal distances from each other, and are so arranged, that each tooth of the under side corresponds to the space between two teeth m the upper side. Their number depends upon the number of coils of roving that may be required to fill a bobbin ; and consists in the usual machines of from 20 to 22 The rod «3 may be shifted in the puppet o3, like the fork p3 of the rack-rod, upon the rod n3, and along the surface of ws, where two wings tt3 ^3 are placed, to keep the fork in a straight direction. Upon the bar tn3, there are the pivots or fulcra of two stop catches w3 a;3, of which the uppermost presses merely by its own weight, but the undermost by means of a counterweight y3, against the rack, and causes them thus to faU in between the teeth. In fig. 414, v^ shows the pivot of the catch or detent w;3 by itself, the detent itself being omitted, to render the construction plainer. A pushing rod /3, upon which there is a pin above at 53, that passes behind the rack rod, between this and the bar m^, has for its object to remove at pleasure the one or the other of the two catches; the upper, when the upper end of the rod pushes against it; the under, by means of the above mentioned pin s3. Both the catches are never raised at once, but either the under or the upper holds the rack bar fast, by pressing against one of the teeth. The vertical motion up or down, which the rod Is must take to effect the lifting of the catches, is given to it from the copping beam p ; since upon it a horizontal arm r«, fig. 414, is fixed, that lays hold of that rod. Upon the pushing rod are two rings A3 and fcs, each made fast by a screw. When the copping beam is in the act of going up, the arm v3 at the end of this movement, pushes against the ring A3, raises up the rod Z3, and thus removes the catch w3, fig. 4J0, from the teeth of the rod 93, before which It lies flat. At the descent of the coppin? rail, t?2 meets the ring fea, when the motion in this direction is nearly completed, draws down the rod /a a little, by means of the same, and thereby effects the removal of the catch z3, fig. 414, from the rod qa. Every iirae that one of the catches is lifted, the rack recovers its freedom to advance a lilUe bit in the direction of the arrow; so far, namely, till the other catch lavs hold upon the tooth that next meets it. The reason is thus manifest why the teeth of the upper and under sides of the bar 53 are not right opposite to each other, but in an alternate position. ' From the rack-bar, the sliding of the cone fc', and the raising of the shaft yi, each by minute steps at a time, is produced as follows : — A large rectangular lever /i, t;», whose centre of motion is at pi, has at the upper end ?i-/^ll?."? *''™. ' ^,'°"^ ^^^^ through which a stud r3 upon the rack q3 goes, (figs. 413, 414, 410,) so that the lever must follow the motions of the rack bar. The end of the short arm of the lever bears, as already mentioned, the step of the shaft y2; hence the friction disc x' will be raised in proportion as the rack bar advances, and wiU come nearer to the middle point of gi ; consequently, its revolution and the shifting of the bobbins will become slower. Upon the cylindrical rod n3, the piece «> «» furnished with a long slot is made fast, by means of a tube jl, (fig. 410,) and a screw. A fork « u, which by means of the screw nut a* is made fast in the slot, embraces the arm /» of the beut lever ; and a tube n riveted to the surface of ji, is destined to take up the draw rod qi of the cone k^.fig. 410. A weight /«, whose cord 64 is made fast to the cylindri- cal rod 7i3, endeavors to draw this rod continually in the direction of the arrow. In consequence of this arrangement, every time that the pushing bar t3 lifts up one of the ealches, the cone fc', the lever a »», and by it the rack bar qs, are set in motion. It it COTTON MANUFACTURE. 523 obvious, that the motion of the eone may be made greater or less, according as the fork tt 1* is fixed further up or down in the slot of sK . m The number of the teeth upon the bar q3 is so ordered, that the bobbins are quite full when the last tooth has reached the catch and is released by it. The rack bar, being restrained by nothing, immediately slides onwards, in consequence of the traction of the weight /4, and brings the machine to repose by this very movement, for which purpose the following construction is employed. A rectangular lever which has its centre of motion in gi is attached to the side face of the beam a, and has at the end of its hori- zontal arm a pulley d*, over which the cord b* of the counterweight /» is passed. The end of the perpendicular arm is forked and embraces the long and thin rod k*, to whose opposite end the fork l< is made fast. Through this fork the band which puts the ma- chine in motion passes down to the pulley a'. With the bent lever another rod c4 is connected at h*y which lies upon the puppet e3 with a slot at e4, and hereby keeps the lever g* in its upright position notwithstanding the weight fi. In the moment when, as above stated, the rack bar 53 becomes free, the arm p3 of its fork pushes in its rapid advance against the under oblique side of €4, raises this rod, and thereby sets the lever g* free whose upright arm bends down by the traction of the weight, drives the rod k* before it into the ring i* fastened to it, and thus, by means of the fork Z4, shifts the band apon the loose pulley &*. But the machine may be brought to repose or put out of gear at any time merely by shifting the rod ki with the hand. The operation of the bobbin and fly frame may be fully understood from the preceding description. A few observations remain to be made upon the cone fei, the rack-bar 93, and the speed of the work. When we know the diameter of the empty bobbins, and how many turns they should make in a given time in order to wind-on the sliver delivered by the fluted rollers and the spindles ; when we consider the diameters of the spindle pulleys 9, and t% as also the drum m\,fig. 405, we may easily find the diameter which the cone must have for pro- ducing that number of turns. This is the diameter for the greatest periphery of the base. The diameter of the smaller is obtained in the same way, when the diameter of the bobbins before the last winding-on, as well as the number of turns necessary in a given time, are known. A bobbin and fly frame of the construction just described delivers from each spindle in a day of twelve hours, from 6 to 8 lbs. of roving of the fineness of 1| English counts. One person can superintend two frames, piece the broken slivers, and replace the fuU bobbins by empty ones. The loss of cotton wool in this machine consists in the portions carried off from the torn slivers, and must be returned to the lapping machine. The fiivt bobbin and fly frame does not differ essentially from the preceding machine. The rovings from the coarse bobbin and fly frame are placed in their bobbins in a frame called the creel, behind and above the roller beam, two bobbins being allowed for one fluted portion of the rollers. These rovings are united into one, so as to increase the uniformity of the slivers. The invention of the beautiful machine above described is due to Messrs. Cocker and Higgins, of Manchester, and as lately improved by Henry Houldsworth, jun., Esq., it may be considered the most ingeniously combined apparatus in the whole range of pro- ductive industry. In the fine roving frame the sliver is twisted in the contrary direction to that of the coarse roving frame. For this reason the position of the cone is reversed, so as to pre- sent in succession to the band, or strap, diameters continually greater, in order that the rotation of the bobbins may be accelerated in proportion as their size is increased, because here the flier and the bobbin turn in the same direction, and the winding-on is eflfected by the precession of the bobbin ; but if the winding-on took place by its falling behind, as in the coarse bobbin and fly frame, that is, if the flier turned less quickly than the bobbin, the rotatory speed of the bobbin would be uniformly retarded ; in which case the cone would be disposed as in the coarse frame. When, by any means whatever, a uniform length of thread is delivered by the rollers in a given time, the bobbin must wind it up as it is given out, and must therefore turn with a speed decreasing with the increase of its diameter by successive layers of thread. Hence proceeds the proposition, that the velocity of the bobbin must be in the inverse ratio of its diameter, as already explained. With respect to the bobbin and fly frame, the twist is given to the sliver by means of a spindle, or flier, which turns in the same direction with the bobbin, but qnicker or slower than it, which establishes two predicaments. The first case is where the flier turns faster than the bobbin. Here the winding-on goes in advance, as in the coarse roving frame, or as in throstle spinning, where the yarn is wound on merely in consequence of the friction of the lower disc or washer of the bobbin upon the copping rail, and of the drag of the yam. The second case is where the flier revolves more slowly than the bobbin. Here the winding goes on in arrear, and as the bobbin If 524 COTTON MANUFACTURE. COTTON MANUFACTURE. 525 twns faster, it must receive a peculiar motion, which is uniformly retarded in the ratie 01 Its increase of diameter. This is the case with the fine bobbin and fly frame When the cone is placdl as in Jig 405, the winding-on, in either the coarse or fine frame, re- sults from the difference, whether greater or less, between the rotatory soeed of the flier and bobbin. j h u «i mc iuc» The motion of the bobbin and spindle is simultaneous, and takes place in the same direction, with a difference varying more or less with the varying diameters of the bobbins. To render the matter still clearer, suppose for a moment the spindle to be motionless, then the bobbin must revolve with such a speed as to lap-on the rovinc as . fast as the rollers deliver it. The sliver comes forward uniformly ; but the bobbin bv Its increase of diameter, must revolve with a speed progressively slower. Now mZ pose the spindle set a-whirUng, it is obvious that the bobbin must add to the movement requisite for wmding-on the sliver, that of the spindle in the case of winding-on in arrear, or when it follows the fliers, and subtract its own motion from the twisting motion of the spindles, in the case of winding-on in advance, that is, when the bobbin precedes or turns faster than the fliers; for the diameter of the bobbin bein- Ih inches, 10 turns will lake up 45 inches. Deducting these 10 turns from the 30 made by the spmdle m the same time, there will remain for the effective movement of the ^bbin only 20 turns; or when the diameter of the bobbin becomes 3 inches, 5 turns will take up the 45 inches, if the spindle be at rest; but if it makes 30 turns in the !?°'VKt-^^^'''J''fl "'f'^'^^ f ^^^ ^°^^^" ^'^" ^^ 25 turns, = 30-5. Hence in the fine bobbin and fly frame, the number of turns of the spindle, minus the number of turns made by the bobbin in equal times, is in the inverse ratio of the diameter of the bobbin We thus perceive, that in the coarse frame the bobbin should move faster 1^1 KK- '^*!! '^'^ ^""^ ^^^1- "^ 'P^^'^ '^°**^^ «l^*ys ii ! I t ont the whole length of the male in portions containing six flutings, which are coupled together by squared ends fitted into square holes. The skewers upon which the bobbins containing the rovings from the bobbin and fly or stretching frame are set up, are seen at ai, ai, a>, arranged in three rows in the creel z. The soft threads unwound from these bobbins, in their way to the drawing rollers, pass first through eyelets in the ends of the wire arms b\ then through the rings or eyes of the guide bar w, and enter between the back pair of rollers. Th€ lumber of these bobbins is equal to the number of spindles in the mule, and twice as f real as the number of fluted portions of the rollers ; for two threads are assigned to each portion. The carriage consists of two cast-iron side pieces, and several cast-iron intermediate similar pieces, such as /a, which all together are made fast to the planks 62, c«, d». The top IS covered in with the plank ka. The carriage runs by means of its cast-iron grooved wheels, upon the cast-iron railway /2, which is fixed level on the floor. The spindles stand upon the carriage in a frame, which consists of two slant rails xs, xiy connected by two slender rods ya, and which frame may be set more or less obliquely. The lower rail carries the brass steps for the points of the spindles b»; upon the upper rail brass slips are fixed pierced with holes through which the tops of the spindles play. The spindles are as usual made of steel, perlectly straight, turned truly round, and are all arranged in one plane. To each of them a small wooden or cast-iron whorl gi is u A^^' "^^^^ ^""^ distributed into groups of 24, and the whorls are arranged at such different heights, that only two of them in each group are upon a level with each other. A small brass head A2, which every spindle has beneath the upper slant rail of the frame xa, prevents their sitting down into the step, during their rotation, or Sliding off their cop of yarn, ci are drums, mounted in the carriage in a plane at right angles to the plane in which the spindles are placed. At top they have a double groove for a cord to run in, and the motion which they receive from the great fly wheel, or rim of the mule (not visible m this view) they impart to the spindles. Such a drum is assigned to every 24 spindles ; and therefore a mule of 480 spindles contains 20 drums. In the middle of the carriage is seen the horizontal puUey fca, furnished with three grooves, which stands in a Ime with the drums c3. The motion is given to the drums c3, upon the right hand half of the carriage, by a single endless band or cord which proceeds from the middle groove of the pulley fc3 The rotation of the spindles is produced by a slender cord, of which there are 12 upon each drum c3; because every such cord ?oes round the drum, and also every two wharves which stand at the same level upon the spindles. It is obvious that the drums, and consequently the spindles, must continue to revolve as long as the main rim of the mule IS turned, whether the carriage be at rest or in motion upon its railway. If we suppose the carriage to be run in to its standing point, or to be pushed home to the spot from which it starts in spinning, its back plank di will strike the post os upon the fixed frame, and the points of the spindles will be close in front of the roller beam. The rollers now begin to turn and to deliver threads, which receive immediately a portion of their twist from the spindles; the carriage retires from the roller beam with somewhat greater speed than the surface speed of the front rollers, whereby the threads receive a certain degree of stretching, which affects most their thicker and less twisted portions, and thereby contributes greatly to the levelness of the yarn. When the carriage has run out to the end of its course, or has completed a stretch, the fluted roUers suddenly cease to revolve (and sometimes even beforehand, when a second stretch is to be made), but the spindles continue to whiri till the fully extended threads have received the proper second or after-twist. Then the carriage must be put up, or run back towards the rollers, and the threads must be Avound upon the spindles. This IS the order of movements which belong to the mule. It has been shown how the rotation of the spindles is produced. For winding-on the yarn the carriage has a peculiar apparatus, which we shall now describe. In front of it, through the whole extent to the right hand as well as the left, a slender iron rod, ds, runs horizontally along, in a line somewhat higher than the mid- die of the copping portion of the spindles, and is supported by several props, such as f . Upon each end of the two rods, ds, there is an arm, gs ; and betwixt these arms an iron wire, called the copping wire, /S, is stretched, parallel with the rod d5. For the support of this wire, there arc several slender bent arms hs extended from the rod ds at several points betwixt the straight arms gs. The rod ds has, besides, a wooden handle at the place opposite to where the spinner stands, by which it can be readily grasped. This movement is applied at the left division of the machine, and it is com- municated to the right by an apparatus which resembles a crane's bill. The two arms. ^, m the middle of the machine, project over the rods ds, and are connected by hinges with two vertical rods;5, which hang together downwards in like manner with two a^i P, proceeding from a horizontal axis ks. COTTON MANUFACTURE. 531 By means of that apparatus the yam is wound upon the spindles in the following manner. As long as the stretching and twisting go on, the threads form an obtuse angle with the spindles, and thereby slide continually over their smooth rounded tips during their revolution, without the possibility of coiling upon them. When, however, the spin- ning process is completed, the spinner seizes the carriage with his left hand and pushes it back towards the roller beam, while with his right hand he turns round the handle of the rim or fly wheel, and consequently the spindles. At the same time, by means of the handle upon the rod rfs, he moves the copping- wire /s, so that it presses down all the threads at once, and places them in a direction nearly perpendicular to the spindles ; as shown by the dotted line ys. That this movement of the copping wire, however, may take place without injury to the yarn, it is necessary to turn the rim beforehand a little in the opposite direction, so that the threads may get uncoiled from the upper part of the spindles, and become slack ; an operation called in technical language the backing off. The range upon which the threads should be wound, in order to form a conical cop upon the spindle, is hit by depressing the copping wire to various angles, nicely graduated by an experienced eye. This faller wire alone is not, however, sufficient for the purpose of winding-on a seemly cop, as there are always some loose threads which it cannot reach without breaking others. Another wire called the counter-faller, Is, must be applied under the threads. It may be raised to an elevation limited by the angular piece ps ; and is counterpoised by a very light weight ms, applied through the bent lever n5, which turns upon the fulcrum o«. This wire, which applies but a gentle pressure, gives tension to all the threads, and brings them regularly into the height and range of the faller fs. This wire must be raised once more, whenever the carriage approaches the roller beam. At this instaxt a new stretch commences ; the rollers begin again to revolve, and the carriage resumes its former course. ^ These motions are performed by the automatic machinery. There is a little eccentric pulley mechanism for moving the guide beam to and frc with the soft yarns, as they enter between the back rollers. On the right hand end of the back roller shaft, a worm screw is formed which works into the oblique teeth of a pinion attached to the end of the guide beam, in which there is a series of holes f(5r the passage of the threads, two threads being assigned to each fluted roller. In the flat disc of the pinion^ an eccentric pin stands up which takes into the jointed lever upon the end of the guide beam, and, as it revolves, pushes that beam alternately to the left and the nght by a space equal to its eccentricity. This motion is exceedingly slow, since for each revolution of the back roller, the pinion advances only by one tooth out of the 33 which are cut in its circumference. After counting the number of teeth in the different wheels and pinions of the mule, or measuring their relative diameters, it is easy to compute the extension and twist of the yams; and when the last fineness is given to ascertain their marketable value. Let the ratio of speed between the three drawing roUers be 1 : 13 . 7| . and the diameter of the back and middle roller three quarters of an inch : that of the front roller one inch ; in which case the drawing is thereby increased 1| times, and 7^ X 1§ = 10. If the rovings in the creel bobbms have been No. 4, the yarn, after passing through the rollers, will b? No. 40. By altering the change pinion (not visible in this view) the fineness may be changed withm certain limits, by altering the relative speed of the rollers. For one revo- lution of the great rim or fly wheel of the mule, the front roller makes about 6 tenths of a turn, and delivers therefore 22-6 lines or 12ths of an inch of yarn, which, in conse- quence of the tenfold draught through the rollers, corresponds to 2-26 lines of roving fed in at the back rollers. The spindles or their whoris make about 66 revolutions for one turn of the rim. The pulleys or grooved wheels on which the carriage runs, perform 0*107 part of a turn while the rim makes one revolution, and move the carriage 24*1 lines upon its rails, the wheels being 6 inches in diameter. ** The 22-6 lines of soft yarn delivered by the front rollers wUl be stretched li lines by the carriage advancing 24-1 lines in the same time. Let the length of the railway, or of each stretch, be 5 feet, the carriage will complete its course after 30 revolutions of the rim wheel, and the 5 feet length of yam (of which 56^ inches issue from the drawing rollers, and 3| inches proceed from the stretching) is, by the simultaneous whiriing of the spmdies, twisted 1980 times, being at the rate of 33 twists for every inch. The second twist, which the threads receive after the carriage has come to repose, is regu- lated according to the qualitj; of the cotton wool, and the purpose for which the yarn is spun. Fo'- warp yarn of No. 40 or 50, for example, 6 or 8 turns of the rim wheel, that is, from 396 to 528 whirls of the spindles for the whole stretch, therefore from 7 to 9 twists per inch will be sufficient. The finished yarn thus receives from 40 to 42 twists per inch. One spinner attends to two mules, which face each other, so that he needs merely turn round m the spot where he stands, to find himself in the proper position for the other mule. For this reason the rim wheel and handle, by which he operates, are not 532 COTTON MANUFACTURE. COTTON MANUFACTURE. 533 s> placed m the niiddle of the length of the machine, but about two fifths of the spindles are to the ngh hand and three fifths to the left ; the rim wheel being towards his rijfht hand. The carriage of the one mule is in the act of going out and spinning, while that of the other is finishing its twist, and being put up by the spinner. The quantity of yarn manufactured by a mule in a given time, depends directly upon the number of the spindles, and upon the time taken to complete every stretch of the carriage. Many circumstances have an indirect influence upon that quanlily and particular])' the degree of skill possessed by the spinner. The better the machine, the steadier and softer all ils pans revolve, the better and more abundant is its production. When the toothed wheels do not work truly into their pinions, when the spindles shake in their bushes, or are not accurately made, many threads break, and the work is much injured and retarded. The better the staple of the cotton wool, and the more careful has been its preparation in the carding, drawing, and roving processes, the more easy and excellent the spinning wUl become : warmth, drj ness, coW, and moisture nave great influence on the ductility, so to speak, of cotton. A temperature of 66<» F.. with an atmosphere not too arid, is found most suitable to the operations of a spinnine null. The finer the yarn, the slower is the spinning. For numbers from 20 to 3^ irom 2 to 3 stretches of warp may be made in a minute, and nearly 3 stretches of weftl for numbers above 50 up to 100, about 2 stretches; and for numbers from 100 to 150 one stretch in the minute. Still finer yarns are spun more slowly, which is not wonderful, since, in the fine spinning mills of England, the mules usually contain upwards of oOO spindles each, in order that one operative may manage a great number and skS' ^ ^ ^^" *"*^^ ^^^ ^*^^^ *^ ^***^* ^""^ remunerate his assiduity In spinning fine numbers, the second speed is given before the carriage is run out to the end of its railway ; during which course of about six inches, it is made to move very slowly. This IS called the second stretch, and is of use in making the varn level by drawing down the thicker parts of it, which take on the twist less readily than the tJimner, and therefore remain softer and more extensible. The stretch may therefore be divided into three stages. The carriage first moves steadily out for about 4 feet while the drawing rollers and spindles are in full play ; now the rollers stop, but the spindles go on whirling with accelerated speed, and the carriage advances slowly about b inches more; then it also comes to rest, while the spindles continue to revolve for » httle longer, to give the final degree of twist. The acceleration of the spindles in the second and third stages, which has no other object but to save time, is effected by a mechanism called the counter, which shifts the driving band, at the proper time, upon the loose pulley, and, moreover, a second band, which had, till now, lain upon its loose pul- ley, upon a small driving pulley of the rim-shaft. At length, both bands are shifted upon tneir loose pulleys, and the mule comes to a state of quiescence. The SELF-ACTOR MULE, or the IRON MAN, as it has been called in Lancashire, is an invention to which the combinations among the operative spinners obliged the masters to have recourse. It now spins good yarn up to 40s with great uniformity ana promptitude, and requires only juvenile hands to conduct it, to piece the broken yams, to replace the bobbins of rovings in the creel, and to remove the finished cops from the spindies. The self-acting mules were first constructed, I believe, by Messrs. Eaton, formerly of Manchester, who mounted ten or twelve of them in that town, four at Wiln, in Derby- shire, and a few in France. From their great complexity and small productiveness, the whole were soon relinquished, except those at Wiln. M. de Jong obtainctl two patents for self actmg mules, and put twelve of them in operation in a mill at Warrington, of Which he was part proprietor ; but with an unsuccessful result. I saw the debris of one o! M. de Jong's self-actors in the factory of M. Nicholas Schlumberger, at GuebwiUer m Alsace, where the machine had been worked for three months, without advantae^ under the care of the inventor, who is a native of that valley. The first approximation to a successful accomplishment of the objects in view, was an jnyention of a self-acting mule, by Mr. Roberts, Of Manchester ; one of the principal points of which was the mode of governing the wiuding-on of the yam into the form of a cop; the entire novelty and great ineenuity of which invention was universally admit- ted, and proved the main step to the JSnal accomplishment of what had so h.ng been a desideratum. For tliat invention a patent was obtained in 1825, and several headstocks upon the principle were made, which are still working successfully. - In 1830, Mr. Roberts obtained a patent for the invention of certain improvements- and by a combination of both his inventions, he produced n self-acting mule, which i^ generally admitted to liave exceeded the most sanguine expectations, and which has been extensively adopted. There are probably, at present, upwards of half a million of simi. dies of Messrs. Sharp, Roberts, and Co.'s construction, at work in the United Kingdom giving great satisfaction lo their possessors. The advantages of these self-ictors' are the followmg : — The saving of a spinner's wages to each pair of mules, piecers only being required, as one overlooker is sufficient to manage six or eight pairs of mules. The production of a greater quantity of yarn, in the ratio of from 15 to 20 per cent. The yarn pos- sesses a more uniform degree of twist, and is not liable to be strained during the spin- ning, or in winding-on, to form the cop ; consequently, fewer threads are broken in these processes, and the yarn, from having fewer piecings, is more regular. The cops are made firmer, of better shape, and with undeviating uniformity ; and, from being more regularly and firmly wound, contain from one third to one half more yarn than cops of equal bulk wound by hand ; they are consequently less liable to ihjury in packing or in carriage, and the expense of packages and freight (when charged by measurement) is considerably reduced. Froin the cops being more regularly and firmly wcmnd, combined with their superior formation, the yarn intended for warps less frequently breaks in winding or reeling, con- sequently there is a considerable saving of waste in those processes. Secondly, the advantages connected with weaving. The cops being more regularly and firmly wound, the yarn, when used as weft, sel- dom breaks in weaving ; and as the cops also contain a greater quantity of weft, there are fewer bottoms, consequently there is a very material saving of waste in the process of weaving. From those combined circumstances, the quality of the cloth is improved, by being more free from defects caused by the breakage of the warp or weft, as well as the sel- vages being more regular. The looms can also be worked at greater speed ; and, from there being fewer stop- pases, a greater quantity of cloth may be produced. That the advantages thus enumerated, as derivable from the use of self-acting mules, have not been overrated, but, in many instances, have been considerably exceeded, I have, by extensive personal inquiry and observation, had ample opportunity of ascer- taining. Statement of the quantity of yarn produced on Messrs. Sharp, Roberts, and Co.*s self- acting mules, in twelve working hours, including the usual stoppages connected with spinning, estimated on the average of upwards of twenty miUs : — No. of Weft. 4| hanks per spindle. 4| - 4f - 4^ No. of Yam. Nu. of Twist. 16 - - 4| hanks 24 - - 4J — - - 32 - - 4 — - - 40 - - 3f — - - Of the intermediate numbers the quantities are proportionate. Results of trials made by Messrs. Sharp, Roberts, and Co., at various mills, to aseer* tain the comparative power required to work self-acting mules, in reference to hand* mules, during the spinning, up to the period of backing ofif. Particulars of the trials referred to, and their results : — U.8 ■ss §, At what Mill, and the Description of No. and kind 5SS Total Force Mule. of Yarn. ill rolnt lley< Wh k. Employed in Spinning. «2 S, 3 Pi ft. p; Messrs. Birley and Kirk, Weft. Ins, ft*. 1b», Self-acting mule, 360 sps. - - 30 to 34 12 58 30 5463 • Hand-mule, 180 sps. - - - ditto 15 36 26 3669) X2=7338 J Messrs. Leech and Vandrey, Twist. t Self-acting mule, 324 sps. - 36 12 70 36 7912 Hand-mules, 324 sps. • - • 36 29 58 161 7273 Messrs. Duckworth 4r Co, TwUt. Self-acting mule, 324 sps. - - 40 12 62 33 6421 Hand-mule, 324 sps. - - - 40 47 36 151 6646 The mode adopted to make the trials was as follows, viz. : A force, indicated by weight in pounds, was applial to the strap working upon the ! S" !^*l '^" ^isadvanta^eoue for the hand-mulee, bein; two for 360 epindles. 5U COURT PLASTER. I driving-pulley of the respective mules, sufficient to maintain the motion of the mnk whilst spinning, which weight, being multiplied by the length of strap delivered by each revolution of the pulley, and again by the number of revolutions made by the pulley whilst spinning, gave the total force in pounds, applied to the respective mules whilst spinning ; for instance, suppose a mule to be driven by a pulley 12 inches diameter (3* 14 feet in circumference), such pulley making 58 revolutions during the spinning as above, and that it required a force equal to 30 lbs. weight to maintain the motion of the mule, then 30 lbs. X 3-14 feet circumference of pulley X 58 revolutions in spinning = 5,463 lbs. of force employed during the spinning, to the period of backing off. Mr. James Smith, of Deanstone cotton works in Scotland, obtained a patent for the invention of a self -actor , in February, 1834. He does not perform the backing-off by reversing the rotation of the spindle, as in common mules, or as in Mr. Roberts', but by elevating the counicrfaller wire, which, being below the ends of the yam or thread, along the whole extent of the carriage, thereby pulls off or strips the spiral coils at the point of the spindle, instead of unwinding them, as of old. This movement he con- siders to be of great importance towards simplifying the machinery for rendering the mule self-acting ; and the particular way in which he brings the stripper into action is no doubt ingenious, but it has been supposed by many to strain the yam. He claims as his invention the application and adaptation of a mangle wheel or mangle rack to the mule, for effecting certain successive movements, either separately or in conjunction ; he claims that arrangement of the carriages of a pair of mules, by which the stretch is caused to take place over part of the same ground by both carriages, and thereby the space required for the working of the pair of mules is greatly diminished ; and he claims the application of a weight, spring, or friction, for balancing the tension of the ends of the threads. A patent was granted, in April, 1835, to Mr. Joseph Whitworth, engineer in Man diester, for some ingenious modifications of the mechanism of the mule, subservient to automatic purposes. His machinery is designed, first, to traverse the carriage in and out, by means of screws or worm-shafts, which are placed so as to keep the carriage parallel to the drawing rollers, and prevent the necessity of squaring bands, hitherto universally employed : secondly, his invention consists in an improved manner of work- ing the drums of a self-acting mule by gear ; thirdly, in the means of effecting the backing off; fourthly, in the mechanism for working the faller-wire in building the cops; and fifthly, in the apparatus for effecting the winding of the yams upoa the spindles. As regards the throstles and doubling frames, his improvements apply, first, to the peculiar method of constructing and adapting the flyers and spindles, and producing the drag ; and, secondly, to the arrangement of the other parts of the doubling machinery. See Lace-Making, Singeing, Textile Fabric, Thbead Manufacture, and Weaving. We extract the following from the Circular of Hermann Cox and Co., dated 19th July, 1852. Export from Ut January to 5th May, as follows : 1853. 1851. Exportationa of Yarn - - - 60,399,189 lbs. 42,630,812 lbs. „ Manufactured Goods - 509,360,295 yda 493,915,720 yds. consequently a considerable surplus on both over last year ; the official return till 6th June, just out^ again shows an increase, viz. : 1852. 1851. ExportetionsofYarn - - - 68,418,111 lbs. 54,634,870 lbs. „ Manufactured Goods - 649,841,927 yda 630,581,674 yda The following is a return of exports from Hull, from Ist January till 30th June : Twist. Other Yam. Manufactured Cotton Goods. Raw Cotton. 1862. - 83,182 bale& 12,115 bales. 11,536 bales. 66,186 bales. 1861. - 31,601 „ 9,634 „ 11,347 „ 83,054 „ COTTON. AMERICA 535 1351. 1R.W, Stock Ist September in the Ports - Receipts till 22d June ... Shipments to Europe till 22d June Deduct Stock 22d June - . - American Consumption for 1861 148,000 bales. 2,250,000 „ 128,000 bales. 2,936,000 „ 2,398,000 „ 1,768,000 „ 640,000 „ 304,000 „ 3,064,000 „ 2,263,000 „ 801,000 „ 201,000 „ 336,000 bales. 600,000 bales. Last year the American spinners took from the above-named last date till Ist Sept, 137,000 bales. FRANCE. Notwithstanding 96,348 bales larger supply, the stock is still 12,293 bales smaller than last year. 1851. Stock, 1st January. Imports to Ist July. Total. Deduct Stock, Ist July. Leaves for Consumption. Havre Marseilles or 7,612 bales per Havre Marseilles 39,825 15,095 210,140 26,124 249,965 41,219 78,377 17,479 171,588 bales. 23,740 „ 64,920 week. 22,767 7,661 236,264 297,514 36,098 291,184 1S52. 320,281 42,759 95,856 75,271 8,292 195,328 bales. 245,010 balea 34,467 „ 30,428 332,612 363,040 83,663 279,477 balea or 10,749 bales per week this year against 7,512 bales in the same period last year, of 7,326 bales average of 1851. REMAINING CONTINENT. We find the consumption of the first six months of 1851 and 1852 to be as follows: i851. Stock, Ist January. Direct Imports. ToUL Deduct Stock, UtJuly. Leaves for Coiwumption. Hamburg ... Bremen .... Petersburg: and Sweden Amsterdam . - - Rotterdam ... Antwerp . • . • Trieste . - . - Sp«iQ, Portugal, and Italy 6,300 89 5,575 1,362 467 4,578 22,596 6,000 33,730 21,191 7,000 4,888 1,912 25,173 79.582 68,000 40,030 21,280 12.575 6.250 2,379 29,751 102,178 74,000 6,730 12,133 4,0(10 2.698 1,333 8,500 49,004 8,000 33.300 bales. 9,147 „ 8,575 „ 3.552 „ 1,046 „ 21,251 „ 53,174 ., 66,000 „ 46,967 241,476 Ad(j 288,413 92,398 1 Export from England 196,045 bales. 95,300 „ Total . 291,345 bales. or 11,206 bales per week. 536 COTTON. 1852. Hamburg - - - Bremen . - - Petersburg and Sweden Amsterdam Rotterdam Antwerp - - - Trieste ... Spain, Portugal, and Italy stock. Direct ToUL 1st Januitry. Iiii|K>rt8. 5,900 65,929 71.829 1,664 16.306 17,967 2,000 23,000 25,000 2,101 6,890 8.991 928 11.581 12,509 1,196 54.282 55.478 25,914 72.392 98,306 4,219 97,000 101,219 847,377 Deduct Stock 1st July. 17,990 3,304 5,000 4,157 8.350 22,000 29,857 9,000 99,658 Export firom England Total Leaves for Consumption. 53,839 bales. 14663 20.000 n 4,834 » 4,159 33.478 t9 68,449 It 92,219 •> 291,641 bales. 147,000 " 438,641 bales. 1 or 16,870 bales per week, against 11,205 bales in the first half of last year, or against 11,664 bales average of the whole period of 1851. The total consumption of all countries according to the preceding statements is as follows : England America France Kemaining Continent 89,683 bales, against 29,851 bales, 1851. 11,538 „ 6,461 10,749 „ 7,512 16,870 „ 11,205 „ 78,840 65,029 bales per week To which we, however, consider it advisable to add, that this increase in the consump- tion for the first half year (viz., 23,811 bales per week) should not be taken as any criterion against the consumption of the same period last year, when it was so much restricted through the drooping state of prices, and when spinners were induced to use up their whole stocks. We affirm therefore that this increase of consumption should only be considered in comparison with the average consumption of the whole of last year, viz. : In England •- • • > -81,973 bales in 1851. America --.--- 9,479 „ France .--... 7,326 „ Remaining Continent - - • - 11,664 M Against 60,442 bales per week. 78,840 „ this year. We have thus far represented the consumption — the extraordinary increase of the same in all countries, without exception, proves how cheap food, with peace, tends to enlarge consumption ; and it remains therefore only to be hoped that the favorable prospects for the ensuing crop be not blighted. It is clearly evident that present prices do not affect the consumption ; for the planters they are sufficiently remunerative to induce an extension of the culture, and so provide for the world such stocks as would prevent any ill effect arising from a future small or bad crop. It shall now be our endeavor to point out the position of stocks in all Europe on the 31st December this year, supposing the consumption to continue at its present rate: The American crop - - - - - Of which were received by the last list of 22d June Remain to receive - - - - - Stocks in the ports and on shipboard 22d June The average stock left in the ports during the last six years was about 150,000 bales, but we will take for this year only ------- Would leave for all Europe Suppose American spinners take nothing more from 22d June till Ist September. 8,000,000 bales. 2,936,329 „ 63,671 „ 201,773 „ 265«4U 100,000 „ 165,444 „ COTTON. Brought forward From America, floating to England - . - - „ „ „ to other countries - - - „ India „ to England - - - - to receive from other countries till 3 Ist December, equal to last year. England - from Egypty Brazils, and Sundries - 83,000 France - „ Egypt, Brazils, and Smyrna - 26,000 53T 165.444 bale«. 150,000 „ 100,000 100,000 >f Trieste, and ) -r. ^ t» -i j a other Ports, \ »» ^P^ Brazds, and Smyrna 40,000 Total supply for Europe Add stocks in all European ports on 1st July 149,000 „ 664,444 „ 900,421 „ Total Quantity of American, next crop, to be received in England Ditto in Continental ports .... 1,564,865 „ 150,000 „ 75,000 „ 1,789,685 bales. Therefore, if the present consumption of Europe were to continue to the end of th« year, the stock would be only 39,084 in all European ports, not enough for one week. Table of Imaginary Stocks in Great Britain on Slat December, 1852. The American crop ...... 8,000,000 balea Of which were received by the last list of 22d June - - 2,936,329 „ Remain to receive - . . - - Stocks in the ports and on shipboard 22d June The average stock left in the ports during the last six years was about 150,000 bales, but we will take for this year only We will suppose American spinners to take nothing more till 1st September, and supposing the 32 ships loading for France, and 125 for other ports take only Would leave for Great Britain - As the stocks in the interior markets are only one third of those of last year, shipments after August must fall very short ; but supposing England to receive from 1st September till 31st December -.---- Now floating to England - - - - - From India we will suppose . - - . - From Brazils, Egypt, Ac, like last year in the same period - Add stock 1st July in Great Britain Total to receive - JExport until Ist July last year was 95,300 bales, for the same period this year 147,000 bales. We have shown that the Continental stocks, notwithstanding so much larcer receipts, are only near on a par with those of last year ; this leads us to suppose that our market must later assist those by large exports, but we will take such only equal to last year, viz. --.... 63,671 201,773 n tt 265,444 t» 100,000 n 165,444 n 65,444 tt 100,000 tt 150,000 150,000 100,000 83,000 >« »» »» 583,000 717,200 1,300,200 balea 121.000 balesw Leaves - - . . . i,i79,200 „ Whereas the present rate of consumption requires till 31st Dec - 1,031,758 bales. This would leave us a stock at this year's end of all descriptions of 147,442 bales only, not sufficient for the consumption of four weeks ; supposing, however, the consumption to fall to only 83,000 bales per week, the remaining stock would be only 821,000 bale% against 494,000 bales at the end of last year. iMMi I 588 COTTON. § 00 J. 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CO X. ^ Y *o CO O X :i .J- j« u X V 5 c ^ 1 r" C/J Lsl a, c 2 s CO H n o S5 'I I 8 •c o ^ o 4« lit* 00 c^ o •* •^ «i id > o CO o o o CO @ I 1 7 I I (O iO OD t- «o • **» CO O 00 t-> « <9 o t- o o> o »- ® I I I I I .4« •«• lefao Kko -^i >«D to to CO t<- «0 <0 S S O cS O Mio «i^ CO O O 00 O T-i O 00 ® I I I I I lO '^ 00 CO CO O O CO © sr o t- © 'a i-n «''•» <-"• r-*o lO '^ t- O CO o h E t< S b S ■a £ -3 £ ;3 e f^ t3 f** t; ^ t? ^ » H '-' *= 2 3 ^ S COTTON. 543-5 52; o o o O •—I H CM p S5 O O o o 00 < » H PJ O C4 Hi •W'>X s s s o "^ i-T 00 CO 2 o »" lA 01 o< *— «0 CO (O tnpui jwa •jdiCSa o o so 00 « '^ CO «D '^ CO e e s I O O CO 10 " o 00 CO «> O e CO 00 1 s S ^li 00 r- '3V 'VUi^lUg to to •-T Kf o o e* eo © O T o -lizwg *s»u»my ^ o to o o« to" 2 S r- 04 oa e> at eo 00 C't CO "* e« CO w^ ^ 00 kO ^ ■^ t- c* >a •w >o •0 '« $ 9 ••aipiq ima o eo «o_ eo" —' to ^ kO s X «^ OD CD 2 ^4 B 'ovifdiC^ 5 o O o o o o fa o o H 03 S I oS ^ 2 •9V '•ipoi »«SA\. 1 «< o« at et •» a to o< •0 CO CO o o s eo to a> -?* gc •-« to r- •^ »-« t-« © CO r- w 00 r- to •0 ^ c o« ■* to r* •9 « O 1 o S o H 5 00 I 00 »-■ • »-^ s c o 546 COTTON (GUN). COTTON SPINNING. Messrs. Tatham, Cbeetham, and Duncan, obtained in 1846 n patent for sundry improvements in apparatus for cotton spinning. Their first in- vention applies \o the scutcher, a machine by which the cotton is cleansed and lapped in a compact and even sheet or lap upon a roller preparatory to its being fed into the carding engine, and consists in a new arrangement of rollers for compressing or calen- dering thelheet of tjotton previous to its being lapped upon the roller; and also in a new method of weighting the calendering rollers, whereby the pressure is gradually in- creased as the sheet of cotton approaches the lap. The second part of the invention consists in the employment of an apparatus for collecting the fibres of cotton from the dust which is blown by the fan from the scutcher. Tlie third part of the invention is an improvement upon machinery patented by Tatham & Cheetham in March, 1844, which caused the sliver to be twisted as it is delivered from the carding engine into the tin-can receptacle. The fourth relates to the apj)lication of gutta percha tintawan for covering rollers used in the several machines employed in cotton spinning. These substances may be used either alone, or combined with sulphurets, ** Higher Starch Compound— When ordinary starch-xyloidine is treated with a mix- ture of fuming nitric and sulphuric acids, and subsequently washed, it is found to have greatly increased in weight The resulting substance is more combustible than the origina xyloidine, and differs from it in several respects, but is not identical with the pyroxyline obtained from woody fibre. "A sample of this product, which had been left eight or nine months in a room where ight freely entered was found wholly decomposed ; nitrous fumes and vapor of water had been evolved leaving a dark sticky residue. This new substance was soluble in water and in alcohol ; crystallizing from the latter in tufts, which under the microscope had a beautiful arborescent appearance. It remained a couple years or more dissolved in a very small quantity of water. What changes may have taken place in it during that period is unknown, since no proper examination had been previously made, but after the lapse of that Ume, the solution was found to be almost black and strongly acid 548 COTTON (GUN). When neutralized with an alkali it gave a copious precipitate on the addition of nitrat« of silver, and a floceulent salt, or rather mixture of salts, with chloride of calcium, which, when dried and heated with hydrate of potash, evolved ammonia. At the bot- tom of the vessel containing the aqueous solution there had grown a compound crystal, transparent and colorless, with the exception of a few brown specks. It had the rhom> boidal form which oxalic acid usually assumes, and upon further examination and analysis proved to be that substance. "A small sample of this same starch compound, which had been washed repeatedly with glacial acetic acid for complete purification, and which had been kept constantly in the dark was found to have suffered decomposition, nothing remaining but a vis- cous acid liquid. When examining these decomposed explosive compounds, I found in my laboratory a bottle filled with a brown sticky mass ; the label having been de- stroyed by evolved acid, it could not be positively identified, but I have good reason to believe it had originally been the higher starch compound : the substance had a strong odor of hydrocyanic acid. Its solution, in either water or alcohol, had a strong acid reaction. It gave no precipitate with chloride of calcium. Floceulent salts con- taining metallic oxides or baryta, all easily soluble in nitric acid, were readily pro- duced. Its combinations with the alkalis gave dark brown aqueous solutions, from which they separated in an amorphous form on evaporation, but though exceedingly soluble in water, they were precipitated on the addition of alcohol. The mass was probably a mixture of different acids, principally non-azotized, for little nitrogen was discoverable ; and although oxalic acid itself was absent, it is by no means improbable that some higher members of the series, Cn Ilni O4 were present. " Hitro-Mannite. — ^This substance, first described by MM. Flores Domonte and Me- nard, is formed when mannite is dissolved in fuming nitric acid, and precipitated by sulphuric acid. Its formula, according to Strecker, is Cu Ha (NO4 ) Oi*. It is the only known crystallizable body belonging to this group. "My sample of nitro-mannite kept in a glass tube, generally in the dark, has suf- fered some decomposition ; acid fumes have been given off, but the action has nut pro- ceeded far. •' Sugar Compound. — It is well known that cane-sugar submitted to the action of mixed nitric and sulphuric acids is converted into a pasty exp1o.»ive substance, readily soluble in alcohol, but insoluble in water, to which, however, it communicates an in- tensely bitter flavor. According to the observations of H. Vohl, several different compounds are produced simultaneously in this reaction. Diabetic sugar similarly treated gives a similar substance. " I have kept samples of this product, some of which had been merely kneaded with water until the acid was removed, others regained from solution in alcohol. They have shown little signs of decomposition. " Milk-Sugar Compound. — By the same treatment a substance is obtained from milk- sugar closely resembling that just described. Like the previous compound, it can be purified by solution in alcohol, but does not present itself in a crystalline form. "A sample kept in paper was found to be much decomposed. " Caramel Compound. — I procured a similar compound from pure caramel, prepared by means of absolute alcohol. The caramel having been dried and pounced, was placed in fuming nitric acid : it dissolved ; upon the addition of sulphuric acid, a dark- colored oil separated, which became hard and yellow when washed with water. It was soluble in alcohol, but came out from solution without crystallizing, and always of the same color. The compound bore a close resemblance in its various properties to those obtained from sugar. "The sample kept by me has suffered little or no alteration. " 6v,m Compound. — At least two different substances of this explosive character may be produced by the action of nitric acid on gum. If the gum be treated with the fuming acid, it dissolves into a mucilaginous solution, from which water precipitates a white body, slightly soluble in that liquid, and very soluble in alcohol. A sample of this substance has not yet suffered any decomposition. " If sulphuric acid be added to the solution of gum in fuming acid, it precipitates a white substance resembling that from sugar, but not nearly so soluble in alcohol, and very slightly in ether. Moreover, it is only softened, not melted, by a temperature of 212^ Fahr. No specimen of this compound was preserved. " While treating upon this subject, it may not be amiss to append a few observations upon another decomposition of pyroxyline. When good gun-cotton is heated at a tempe- rature a little exceeding that of boiling water, it becomes brown in color, and is disin- tegrated. The odor of nitrous fumes, along with that of some cyanogen compound, is very perceptible. It thus becomes explosive at a lower temperature than formerly, a fact which may account for some of those hitherto unexplained accidents which have •risen from this article, for it is evident that gun-cotton exposed for some time to a CRANES (TUBULAR). 549 degree of heat quite insufficient under ordinary circumstances to cause explosion, may yet be eventually dissipated from the formation of this product "The brown substance thus obtained underwent no visible alteration in the space of foiir jrears. When examined lately it was found to be very soluble in water, but insol- uble in alcohol or ether. Its aqueous solution tasted somewhat bitter, it reacted slightly acid, no crystals were obtained on evaporation. When boiled with a solution of potash, it evolved ammonia. When mixed with a salt of lead or copper it formed brown floceulent precipitates, but none appeared with a silver or lime salt The organic substance which fell in combination with oxide of lead, contained a large amount of nitrogen. That portion of the fibre which had not become brown with heat was found to be no longer pyroxyline ; when freed from the brown matter by washing with water, and dried, it left little residue on explosion; but on the other hand, it dissolved very readily m ether, alcohol, or cold sulphuric acid ; properties of cotton-xyloidine, but not of the original substance. When, however, the manner of its production is considered, we can hardly conceive it identical with a body which would require the introduction of two atoms of hydrogen if formed from pyroxyline. Whether this change which gun-cotton undergoes at a high temperature is at all analogous to the spontaneous decomposition mentioned above, can scarcely be determined, but the presence of azotized compounds m considerable quantity, and of ammonia, rather indicates the reverse. " The rationale of these decompositions is far from being elucidated by the observations here recorded, but as the substances themselves are not now in existence, nor are capable of being procured without long delay, I cannot pursue the investigation further The only general conclusion which can be drawn appears to be, that several substances of the character above described have a tendency to suffer spontaneous decomposition from being oxidized into non-azotized acids at the expense of the peroxide of nitrogen NO^. they contain, which is reduced to the condition of nitric oxide, NO2, and evolved as such, a portion of water being always given off at the same time." COURT PLASTER is a considerable object of manufacture. It is made aa follows: Black silk is strained and brushed over ten or twelve times with the following pre- paration :— Dissolve I an ounce of balsam of benzoin in 6 ounces of rectified spirite of wme; and in a separate vessel dissolve 1 ounce of isinglass in as little water as may be. Strain each solution, mix them, and let the mixture rest so that any undissolved parU may subside; when the clear liquid is cold it will form a jelly, which must be warmed before It is applied to the silk. When the silk coated with it is quite dry it must be linished off with a coat of a solution of 4 ounces of Chian turpentine in 6 ounces of tincture of benzoin, to prevent its cracking.* COW DUNG SUBSTITUTE, in calico printing. Sulphate, carbonate and phos- pnate of hme and soda. ^ CRANES, Tubular, of Mr. W. Fairbairn.^AmoTig the many happy applica- tions of the hollow-girder system of our great engineer, this is one of the most inee- nious. ° " Ktg. 425 is a vertical section of a crane, constructed according to my said invention and calculated for lifting or hoisting weights up to about 8 ton& Fig. 426 is an elevation of the same; fgs. 427, 428, 429, and 430, are cross-sections, on the lines a b cd,ef,gh; andjig. 431 a transverse vertical section on the line ik. a a is the jib which in Its general outline, is of a crane-neck form, but rectangular in its cross-section as particularly shown m Jig.t. 428, 429, and 430. The four sides are formed of metal plates, firmly riveted together. Along the edges the connection of the plates is effected by means of pieces of angle iron. The connections of the plates at the cross-joints on the convex or upper side of the jib, are made by the riveting on of a plate, which covers or overlaps the ends of the two plates to be joined; the riveta at this part are disposed as represented m /^. 432 (a plan of the top plates), and known as 'chain riveting; b b is the pillar, which is firmly secured by a base plate p, to a stone founda- tion b; and fits at top into a cup-shaped bearing c, which is so firmly secured to the side plates of the jib at or near to the point where the curvature commences, and on which bearing the jib is free to revolve. Fig. 431 is a transverse vertical section of the lower part of the jib, showing the manner of fitting the bearings for the chain- barrel (which is placed m the interior), and the spindles and shafts of the wheel-geering. by which the power is applied there to d, is the chain pulley, which is inserted in an aperture formed in the top of the jib. The chain passing over this pulley, enters the interior of the crane, and is continued down to the chain barrel, e is a pulley or roller, which IS interposed about half-way between the chain-pulley and the chain-barrel, for the purpose of preventing the chain rubbing against the plates. J^g. 433 is a plan of the lower platea ^ParUI Pharmacologia. 550 CRANES (TUBULAR). Mg. 484 is a vertical section of another crane constructed upon the same principle as that just described, but calculated for lifting ranch greater weights (says 20 tons); it diflfers in having the lower or concave side a a, of the jib strengthened by means of three additional plates b b b, whereby the interior is divided into one large and three smaller cells, as shown in Jigs. 435 and 436, which are cross sections upon the lines a b, 425 f 483 482 »GO*Oo«ftO ft '-o&c.ft A.TTTYTrf^TjflCfct, 4»Aietoa<6A*c*>(*cb*,tc''-t^vV and c for GlasB Pots Bohemian Glass Pote Cast Steel. Cast Stee]. at Nemours Glass Puts. of Creusot. Silica - - - 70-9 64-6 63-7 65-2 67-4 68-0 680 Alumina - - 24-8 34-4 20-7 25-0 32-0 29-0 280 Oxyde of Iron - 3-8 1-0 4-0 7-2 0-8 2-2 2-0 Magnesia - - trace — -- trace trace 0-5 trace Water - - - — — 10-3 • — — — 10 Wurzer states the composition of the sand and clay in the Hes6i&n crucibles as fol- lows : — Clay; silica 10* 1 ; alumina 65-4; oxydes of iron and manganese 1*2; lime 0-3; water 23 Sand; 95-6 2-1 1-5 0-8 Black had crucibles are made of two parts of graphite and one of fire clay ; mixed with water into a paste, pressed in moulds, and well dried ; but not baked hard in the kiln. They bear a higher heat than the Hessian crucibles, as well as sudden changes of temperature ; have a smooth surface, and are therefore preferred by the mellers of gold and silver. This compound forms excellent small or portable furnaces. Mr. Anstey describes his patent process for making crucibles, as follows : Take two parts of fine ground raw Stourbridge clay, and one part of the hardest gas coke, pre- viously pulverized, and sifted through a sieve of one eighth of an inch mesh (if the coke is ground too fine the pots are very apt to crack). Mix the ingredients together with the proper quantity of water, and tread the mass well. The pot is moulded by hand upon a wooden block, supported on a spindle which turns in a hole in the bench ; there is a gauge to regulate the thickness of the melting pot, and a cap of linen or cotton placed wet upon the core before the clay is applied, to prevent the clay from sticking partially to the core, in the taking off; the cap adheres to the pot only while wet, and may be removed without trouble or hazard when dry. He employs a wooden bat to assist in moulding the pot ; when moulded, it is carefully dried at a gentle heat. A pot dried as above, when wanted for use, is first warmed by the fire-side, and is then laid in the fur- nace with the mouth downwards (the red cokes being previously damped with cold ones in order to lessen the heat) ; more coke is then thrown in till the pot is covered, and it is now brought up gradually to a red heat. The pot is next turned and fixed in a proper position in the furnace, without beine allowed to cool, and is then charged with cold iron, so that the metal, when melted, shall have its surface a little below the mouth of the pot. The iron is melted in about an hour and a half, and no flux or addition of any kind is made use of. A pot will last for fourteen or even eighteen successive melt- ings, provided it is not allowed to cool in the intervals; but if it cool, it will probably crack. These pots, it is said, can bear a greater heat than others without softening, and will, consequently, deliver the metal- in a more fluid state than the best Birmingham pots will. See a figure of the crucible mould under Steel. CRYSTAL is the geometrical form possessed by a vast number of mineral and saline substances; as also by many vegetable and animal products. The integrant particles of matter have undoubtedly determinate forms, and combine with one another, by the attraction of cohesion, according to certain laws, and points of polarity, whereby they assume a vast variety of secondary crystalline forms. The investigation of these laws belongs to crystallography, and is foreign to the practical purpose of this volume. * This cnictble had been analyzed before being baked in tlie kiln. 556 CURRYING OF LEATHER. Btmctions are given nncler each oWeet of manufacture which requires crystallization, how to conduct this proeees. See 13orax, Salt, Ac. CUDBEAR was first made an article of trade in this country, by Dr. Cuthbert Gordon, from whom it derived its name, and was originally manufactured on a great scale by Mr. G. Mackintosh, at Glasgow, nearly 80 years ago. Cudbear or persio is a powder of a violet red color, difficult to moisten with water, and of a peculiar but not disagreeable odor. It is partially soluble in boiling water, becomes red with acids, and violet blue with alkalis. It is prepared in the same way as archil, only towards the end the substance is dried in the air, and is then ground to a fine powder, taking care to avoid decocnposition, which renders it glutinous In Scotland they use the lichen tar- tareus, more rarely the lichen calcareus, and omphalodes ; most of which lichens are imported from Sweden and Norway, under the name of rock moss. The lichen is suffered to ferment for a month, and is then stirred about to allow any stones which may be pre- sent to fall to the bottom. The red mass is next poured into a flat vessel, and left to evaporate till its urinous smell has disappeared, and till it has assumed an agreeable color verging uiMjn violet. It is then ground to fine powder. During the fermentation of the liclien, it is watered with stale urine, ot with an equivalent ammoniacal liquor of any kind, as in making archil. CUPELLATION is a mode of analyzing gold, silver, palladium, and platinum, by adding to small portions of alloys, containing these metals, a bit of lead, fusing the mixture in a little cup of bone earth called a cupel, then by the joint action of heat and air, oxydizing the copper, tin, &c., present in the precious metals. The oxydes thus pro- duced are dissolved and carried down into the porous cupel in a liquid state, by the vitrified oxvde of lead. See Assay, Gold, and Silver. CURRYING OF LEATHER (Corroyer, Fr. ; Zurichten, Germ.) is the art of dressing skins after they are tanned, for the purpose of the shoe-maker, coach and harness maker, &c., or of giving them the necessary smoothness, lustre, color, and suppleness. The currier's shop has no resemblance to the tanner's premises, having a quite different set of tools and manipulations. The currier employs a strong hurdle about a yard square, made either of basket twigs, or of wooden spars, fixed rectangularly like trellis work, with holes 3 inches square, upon which he treads the leather, or beats it with a mallet or hammer, in order to soAen it, and render it flexible. The head knifCj called in French couteau cl revers, on account of the form of its edge, which is much turned over, is a tool 5 or 6 inches broad, and 15 or 16 long; with two handles, one in the direction of the blade, and the other perpendicular to it, for the purpose o( guiding the edge more truly upon the skin. The pommel (paumelle) is so called because it clothes the palm of the hand, and performs its functions. It is made of hard wood, and is of a rectangular shape, 1 foot long, 5 inches broad, flat above and rounded below. It is furrowed over the round- ed surface with transverse parallel straight grooves. These grooves are in section sharp-edged isos- celes triangles. Fig3, 441 and 442, repre- sent the pommel in an The flat surface is provided with a leather strap lor secur- Pommels are made of different sizes, and uppt:/ and under view. ing «t to the hand of the workman. witL grooves of various degrees of fineness. Cork pommels are also used, but they are rot grooved. Pommels serve to give grain and pliancy to the skins. The stretching iran, Jig. 443, is a flat plate of iron or copper, fully a fourth of an inch t»»ick at top, and thinning off at bottom in a blunt edge, shaped like the arc of a circle of large diameter, having the angles a and 6 rounded, lest in working they should penetrate the leather. The top cis mounted with leather to prevent it from hurting the hands. A copper stretching knife is used for delicate skins. The workman holds this tool nearly perpendicular, and scrapes the thick places powerfully with his two hands, esnecially those where some tan or flesh remains. He thus equalizes the thickness of CURRYING OF LEATHER. 557 the skin, and renders it at the same time more dense and uniform in texture. This tool is of very general use in currying. The round knife, Jigs. 444 and 445 {lunette in French), is a circular knife from 10 to 12 inches in diameter, with a round 4 or 5 inch hole in its centre, for introducing the hands and working it It is concave, as shown in the section Jig. 446, presenting the form of a spherical zone. The concave part is that applied to he ^km. Its edge is not perfectly straight; but is a little turned over on the side opposite to the skin, to preven* 446 so 444 ^^ "^^ 1^ 445 *' from entering too far into the lea- ther. The urrier first rlopes off with the head kn\fe from the edges, a por- tion equal to what he afterwards re- moves with the round onr. By this division the work is done sooner and more exactly. All r\e rUeo )r greased skins are dressed with the roand knife. The cleaner is a straight two-han- dled knife two inches broad, of which there are two kinds, a sharp-edged and a blunt one. Fig. 446. The mace is made of wood, having a handle 30 inches long, with a cubical head or mallet ; upon the two faces of which, parallel to the line of the handle, there are 4 pegs of hard wood turned of an egg-shape, and well polished, so as not to tear the moistened leather when it is strongly beat and softened with the mace. The horse or trestle. Jig. 447, consists of a strong wooden frame, A b c d, which serves as a leg or foot. Upon the middle of this frame there are two uprights, e f, and a strong cross beam, g, for supporting the thick plank h, upon which the skins are worked. This plank may be set at a greater or less slope, according as its lower end is engaged in one or other of the cross bars, 1 1 1 1, of the frame. In the figure, a skin £ is represented upon the plank with the head knife upon it, in the act of being pared. A cylindrical bar fixed horizontally at its ends to two buttresses projecting from the wall, serves by means of a parallel stretched cord, to fix a skin by a coil or two in order to dress it. This is accordingly called the dresser. The tallow cloth is merely a mop made of stout rags, without the long handle ; of which there are several, one for wax, another for oil, &.c. Strong-toothed pincers with hook-end handles, drawn together by an endless cord, are employed to stretch the leather in any direction, while it is being dressed. The currier uses clamps like the letter U, lo fix the edges of the leather to his table. His polisher is around piece of hard wood, slightly convex below, with a handle standing upright in its upper surface, for seizing it firmly. He first rubs with sour beer, and finishes with barberry juice. Every kind of tanned leather not intended for soles or such coarse purposes, is generally curried before being delivered to the workmen .who fashion it, such as shoe- makers, coachmakers, saddlers, &c. The chief operations of the currier are four : — 1. Dipping the leather, which consists in moistening it with water, and beating it with the mace or a mallet upon the hurdle. He next applies the cleanersy both blunt and sharp, as well as the head knife, to remove or thin down all inequalities. After the leather is shaved, it is thrown once more into water, and well scoured by rubbing the grain side with pumice stone, or a piece of slaty grit, whereby it parts with the bloom, a whitish matter, derived from the oak bark in the tan pit. 2. Applying the pommel to give the leather a granular appearance, and correspondent flexibility. The leather is first folded with its grain side in contact, and rubbed strongly with the pommel, then rubbed simply upon its grain side ; whereby it becomes extremely flexible. 3. Scraping the leather. This makes it of uniform thickness. The workman holds the tool nearly perpendicular upon the leather, and forcibly scrapes the thick places with both his hands. 4. Dressing it by the round knife. For this purpose he stretches the leather upon the wooden cylinder, lays hold of the pendent under edge with the pincers attached to his girdle, and then with both hands applies the edge of the knife to the surface of the leather, slantingly from above downwards, and thus pares off the coarser fleshy parts of the skin. This operation requires great experience and dexterity; and when well per- formed improves greatly the look of the leather. The hide or skin, being rendered flexible and uniform, is conveyed to the shed or drying house, where the greasy substances are applied, which is called dubbing (daubing) or stufl^ng. The oil used for this purpose is prepared by boiling sheep-skins or doe-skins, in cod oil. This application of grease is often made before the graining board or pommel is employed. Before waxing, the leather is commonly colored by rubbing it with a brush dipped into a composition of oil and lamo black on the flesh side, till it be thoroughly black ; it is 558 CUTLERY. then black-sized -with a bnish or sponge, dried, tallowed with the proper cloth, and slicked upon the flesh with a broad, smooth lump of glass; sized again with a sponge* and when dry, again curried as above described. Currying leather on the hair or grain side, termed black on the grain, is the same in the first operation with that dressed on the flesh, till it is scoured. Then the first black is applied to it while wet, by a solution of copperas put upon the grain, after this has been rubb^'d with a stone ; a brush dipped in stale urine is next rubbed on, then an iron slicker is ased to make the grain come out as fine as possible. It is now slufled with oil. When dr>', it is seasoned ; that is, rubbed over with a brush dipped in copperas water, on the grain, till it be perfectly black. It is next slicked with a good grit-stone, to take out the wrinkles, and smooth the coarse grain. The grain is finally raised with the pommel or graining board, by applying it to the leather in diflerent directions. When thoroughly dry, it is grained again in two or three ways. Hides intended for covering coaches are shaved nearly as thin as shoe hides, and blacked upon the grain. CUTLERY. (Coutelkrie, Fr. ; Messerschmidwaare, Germ.) Three kinds of steel are made use of in the manufacture of different articles of cutlery, viz., common steel, shear steel, and cast steel. Shear steel is exceedingly plastic and tough. All the edge tools which require great tenacity without great hardness are made of it, such as table knives, scythes, plane-irons, &c. Cast steel is formed by melting blistered steel in coveitx: crucibles, with bott* glass, and pouring it into cast-iron moulds, so as to form it into ingots ; these ingots are then token to the tilt, and drawn into rods of suitable dimensions. No other than cast steel "«• Razors are hardened and tempered in a similar manner to penknives. They are however, left harder, being only let down to yelJow or brown color * The for-ing of scissors is wholly performed by the hammer, and all the sizes are made by a single hand. The anvil of the scissor-maker weighs about U cwt.; it measures, on the face, about 4 by II inches. It is provided with two grates o? grooves for the r^ ception of various little indented tools termed by the workman bosses; one of these bosses IS employed to give proper figure to the shank of tl^* scissors ; another for form- ing that part which has to make the joint ; and a third is n4lle use of for giving a proper figure to the upper side of the blade. There is also another anvil placed on the same block containing two or three tools called beak-irons, each consisting of an upright stem about 6 mcht^s high, at the top of which a horizontal beak projects ; one of these beaks IS conical, and is used for extending the bow of the scissors ; the other is a segment of a cylinder with the round side upwards, containing a recess for giving a proper shape and smoothness to the mside of the bow. s f h » pc «uu The shank of the scissors is first formed by means of one of the bosses, above de- scribed, leaving as much steel at the end as will form the blade. A hole is then punched about J inch m width, a little above the shank. The blade is draT^n out and finished and the scissors separated from the rod a little above the hole. It is heated a third time! and the small hole above mentioned is extended upon the beak-irons so as to form the bow. This finishes the forging of scissors. They are promiscuously made in this way. without any other guide than the eye, having no regard to their being in pairs. They are next annealed for the purpose of filing such parts of them as cannot be ground, and afterwards paired. ' The very large scissors are made partly of iron, the blades being of steel. ci^^^^^'^J^^ forging, the bow and joints, and such shanks as cannot be ground, are filed. The rivet hole is then bored, through which they are to be screwed or riveted together. This common kind of scissors is only hardened up to the joint They are tempered down to a purple or blue color. In this state they are taken to the grinder. Grinding and polishing of cutlery.— The various processes which come under this denomination are performed by machinery, moving in general by the power of the steam- engine or water-wheel. Grinding wheels or grinding mills are divided into a number of separate rooms • every room contains six places called troughs ; each trough consists of a convenience for run- ning a grindstone and a polisher at the same time, which is generally occupied by a man The business of the grinder is generally divided into three stages, viz., erindine. glazing, and polishing. ' ^ ^' The grinding is performed upon stones of various qualities and sizes, depending on the articles to be ground. Those exposing much flat surface, such as saws, fenders, &c., require stones of great diameter, while razors, whose surface is concave, require to be ground upon stones of very small dimensions. Those articles which require a certain temper, which is the case with most cutting instruments, are mostly ground on a wet stone; [or which purpose the stone hangs within the iron trough, filled with water to such a height that its surface may just touch the face of the stone. Glazing IS a process following that of grinding: it consists in giving that degree of lustre and smoothness to an article which can be eflfected by means of emery of the various degrees of fineness. The tool on which the glazing is performed, is termed a glazer. It consists of a circular piece of wood, formed of a number of pieces in such a manner that its edge or face may always present the endway of the wood. Were it made otherwise, the contraction of the parts would destroy its circular figure. It is fixed upon an iron axis similar to that of the stone. Some glazers are covered on the face with leather, others with metal, consisting of an alloy of lead and Un ; the latter are termed caps. In others, the wooden surface above is made use of. Some of the leather-faced glazers, such as are used for forks, table knives, edge tools, and all the coarser polished articles, are first coated with a solution of glue, and then covered with emery. The surfaces of the others are prepared for use by first turning the face verf CIDER. 561 true, then filling it with small notches by means of a sharp-ended hammer, and lastly filling up the interstices with a compound of tallow and emery. The pulley of the glazer is so much less than that of the stone, that its velocity is more than double, haying in general a surface-speed of 1,600 feet in a second. The process of polishing consists in giving the most perfect polish to the different articles. Nothing is subjected to this operation but what is made of cast steel, and has been previously hardened and tempered. The polisher consists of a circular piece of wood covered with buff leather, the sur- face of which is covered from time to time, while in use, with the crocus of iron, called also colcothar of vitriol. The polisher requires to run at a speed much short of that of the stone, or the glazer. Whatever may be its diameter, the surface must not move at a rate exceeding 70 or 80 feet in a second. CYANATES; saline compounds of cyanic acid with the bases potash, soda, ammo- ma, baryta, ard or frame, Jig. 452 ; four small metallic bands of the same & i«o h • 0«-j d d d d "J. -m-^ml^ metals as the plates, also shown in ^g, 452, a small handle and a box of small nails Of tacks, and a phial of iodine. After fixing, by the metallic bands and the small nails, the plate upon the thin board, with the silver uppermost, several particles of iodine are then to be spread in the dish d, at the bottom of the box,^g^. 450, and 451. The thin board with the plate, 18 next placed, with the silver beneathy upon small supports at the four comers of the box, and its cover is applied. The plate must be left in this position till the surface of the silver acquires a fine golden hue, caused by the vapors of the iodine rising through the gauze cover of the dish, and condensing upon it ; but it should not be allowed to assume a violet tint. The room should be darkened, and no heat should be employed. When the box is in constant use it gets impregnated with iodine, and acts more uni- formly and rapidly ; but in general states of the atmospheric temperature this operation will be efiected in about twenty minutes. If the purple color be produced, the plate must be repolished, and the whole process repeated. The plate with its golden hue is to be introduced with its board into the frame, Jigs, 453, 454, 455, which is adapted to the camera obscura. During this transfer the light must not be suffered to strike upon the surface of the plate ; on which account, the camera obscura may be lighted briefly with a small wax taper. 3. The plate is now submitted to the third operation, that of the camera obscurn. Jigs. 456 and 448, and with the least possible delay. The action of this machine is ob- viously quicker the brighter the light which acts upon it ; and more correct, according as the focus is previously accurately adjusted to the place of the plate, by moving backwards and forwards a roughened pane of glass, till the focal point be found ; and the plate is to be inserted precisely there, see Jigs. 453, 454, 455. This apparatus ex- actly replaces the ground glass. While the prepared plate is being fastened, the camera must be closed. The darkening sliutters, b b, of the apparatus are opened by means of the two semicircles, a a. The plate is now in a proper position to receive and retain the impression of the image of the objects presented the moment that the camera is opened. Experience alone can teach the proper length of time for submitting the plate to the concentrated rays of light ; because that time varies with the climate, the sea- sons, and the time of day. More time should not be allowed to pass than what is necessary for fixing a distinct impression, because the parts meant to be clear would be apt to become clouded. 4. The fourth is the operation with quicksilver, which must follow as soon as pos- sible the completion of the third. Here a phial of quicksilver, a spirit-lamp (the apparatus represented in Jigs. 457 and 458), and a glass funnel with a long neck, are required. Tlie funnel is used for pouring the mercury into the cup c, placed in the DAGUERREOTYPE. 565 bottom of the apparatus, so as to cover the bulb of the thermometer / ^o daylight must now be admitted, but that of a small taper only should be used by the operator in conducting the process. The board with the plate is to be withdrawn from the J' camera, and inserted into the grooves of the blackened board, b, Ji^. 467. This black board is laid back into the box at an angle of 45° with the horizon ; the prepared metal surface h being placed undermost, so that it may be viewed through the side glass (7; and the cover, a, of the box must be put down gently, to prevent any par- tides of mercury from being thi-own about by the agitation of the air. The whoU being thus prepared, the spirit-lamp is lighted, and j>laeed under the cup containing the mercury, and left there until the thermometer indicates a temperature of 140*^ Fahr., when the lamp is to be removed. The heat should in no case be permitted to exceed 167^ F. „ , , 1 . • Tlie impression of the image of nature is now actually made upon the plate ; but it is yet invisible ; and it is only after a lapse of several minutes that faint tracings of the objects begin to be seen through the peep-glass by the momentary gleam of a taper. The plate should be left in the box till the thermometer has cooled to 113° F., when it is to be taken out • After each operation, the interior of the apparatus, and the black board or frame, should be carefully wiped, in order to remove every particle of mercury. The picture may now be inspected in a feeble light, to see how far the process has succeeded. The plate, freed from the metallic bands, is to be placed in a box, pro- vided with a cover and grooves, to exclude the light, till it is made to undergo the fifth and last operation, which may be done after any convenient interval of time without detriment, provided the plate be kept in the dark. The following articles are now required : 1, strong brine, or a weak solution of hyposulphate of soda ; 2, the api^- ratus represented in Jigs. 459 and 460 ; 3, two troughs of tin-plate ; 4, a jug of dis- tilled water. The object of this process is to fix the photogenic picture. One of the 566 DAGUERREOTYPE. troughs is to be filled with brine to the depth of an inch, and the other with pur« water, both liquids being heated somewhat under the boiling pitch. The solirtion of hyposulphite of soda is preferable, and does not need to be warm. The plate is to be first immersed in the pure water for a moment, and transferred immediately to the saline solution, and moved to and fro in it to equalize the action of the liquor. When- ever the yellow tint of the iodine is removed, the plate is to be lifted out by the edges, and dipped straightway in the water-trough. The apparatus of fas. 459, and 460, is then brought into use, with a vessel filled with distilled water, hot^ but not boiling. The plate, when lifted out of the water-trough, is to be placed immediately on the inclined plane e ; and without allowing it time to dry, is to be floated over with the hot distilled water from the top, so as to carry oflF all the saline matter. As the quick- silver which traces the images will not bear touching, the silvered plate should be se- cured by a cover of glass, made tight at the edges by pasting paper round them. In Jig. 451, which is a plan view of the iodine-box apparatus, e is an interior cover; d is the iodine-dish ; e is the thin board to which the silvered plate is fixed, as shown at fg. 450 ; g is the cover of the box ; h h are small rods, at the four corners of the inclined lining, k, of the box, to support the lid c ; ^' is a gauze of wire-cloth cover, to diffuse the iodine vapor; k is the wooden lining, sloping like a hopper; d d,\xi Jig. 454, are buttons to fasten the board on the doors; e shows the thickness of the frame; /is the silvered plate. In Jig. 461, a is the ground glass of the camera; 6 is a mirror inclined about 45° to the horizon, by means of the rod /. The image of the object is easily brought into focus by moving forward or backward the sliding-box d, in laying hold of it with both hands by the projections a, Jig. 454. When the focus is adjusted, the thumbscrew, /t, fixes the whole. The mirror is kept closed by two hooks at /, which take into small eyes at g. The frame and ground glass plate are withdrawn and replaced by the frame carrying the prepared plate, as represented hnfg. 448, with the shading doors, h, open in the camera. These doors and the sliding-box d are lined with black velvet. The object glass is achromatic and periscopic, the concave being outside in the camera; its diameter is about 3| inches, and focus about 13 inches. A diaphragm is placed before the object glass, at 3| inches from it, and its aperture may be closed by a plate moving in a pivot. This camera reverses the objects from left to right; but this may be obviated by placing a plane mirror on the outside beyond the aperture of the diaphragm, as at /, Jig. 456, where it is fixed by means of a screw, k. Loss of light is thereby occasioned. Fig. 457 is an upright section, &ndfg. 458, a front elevation of the mercurial appa- ratus, a, the cover; b, the black board, with grooves to receive the board. A; e, the cup of quicksilver; d, the spirit-lamp; e, a small cock, through whixjh the quicksilver may be run off, if the apparatus be laid to one side ; /, the thermometer ; g, a glass window ; h, the board bearing the metallic plate ; /, a stand for the spirit-lamp, which is held by the ring k, so that its flame may strike the bottom of the cup. The whole of the inside of the apparatus should be blackened and varnished. Mg. 459 is a front view of the washing apparatus made of tin plate, varnished. The plates, to be washed, are laid on the angular ledge, d; eisa ledge to conduct the water to the receptacle c. Fig. 460 is a side view of the washing apparatus. The patent was enrollea in February, 1840. {See Newton's Journal, C. S. xyl, I.) Mr. Richard Beard having purchased from M. Daguerre a license to practise his invention above described, received from a foreigner a communication of certain im- provements, for which he obtained a patent in June, 1840. The first of these is the substitution of a concave reflecting mirror for the lens in the camera obscura. Fig. 462 represents in section a slight wooden box, a a, open at the front, opposite to the person sitting for the portrait In the back part of the box a concave mirror, b, is placed, to reflect the rays coming from the person. A small frame, f, is fixed to an adjustable pedestal, d, which slides in grooves in the bottom of the box, for the purpose of being set at the focal point of the mirror. In this frame, e, a polished Burface is first to be placed for trial, to receive the image correctly, as observed by the operator, by looking through the opening, e, in the top of the box. The prejjared silvered plate is now substituted in the exact place for the trial one. Tlie luminous impression being made, the slide, c^ is withdrawn, and the plate removed ; carefully shut up in a box from the light The second object of this patent is making the prepared surface more uniform, h> passing two plates, with their silvered faces in contact^ several times between hardened rollers, annealing them at a low red heat after each passage. His third object is to use a compound of bromine and iodine, instead of the lattei alone, for coating the silver; which increases its sensibility to light, thereby shortening and improving the operation of taking likenesses. He also recommends to use a com- bination of iodine with nitric acid. Finally, Mr. Beard finds that by placing a screen of any desired color behind the sitter, the appearance of his Daguerreotype portrait is improved. {Newton's Journal, zziiL, 112.) DAGUERROTYPE. 537 M. A. J. F. Claudet, who had also purchased a license from M. Daguerre, obtained a patent in December, 1841, for certain improvements upon the original process. His first object is to give the front of the camera obscura such an aperture as to admit the largest object-glass intended to be used; and of such he provides a series of dif- ferent dimensions, each attached to its board, that may be fitted by a slide to the front of the camera. vi— r One of the greatest difficulties in the Daguerrotype process was the impossibility of ascertaining the precise moment at which the light had produced, on the prepared plate, the effect requisite for the vapor of mercury to bring out the image. By apply- ing that vapor to the plate while the silver surface is being acted upon by the ligh^ the operator is enabled to see when his picture is complete. Another advantage of this joint operation is, that the effect of the mercury upon those parts of the plate which have been acted upon by the light, are more perfect when caused to take place immediately under the luminous influence. Hence, instead of using the distinct box with the cup of quicksilver, he places a cup containing that metal in the camera ob- scura, with its spirit-lamp, and exhales the vapors there. When the mercury has risen to the proper temperature, the aperture of the object-glass is thrown open, and the light, reflected from the object to be delineated, is allowed to operate. He watches the effect through an opening in the side of the camera, where he views the prepared plate by the light of a lantern passing through a piece of red or orange- colored glass in the (other) side of the camera. Whenever the light and mercury, by their simultaneous action, have produced a good image, the object-glass is covered, and the silver plate, with its picture, removed, in order to be washed and finished. M. Claudet embellishes his Daguerrotype portraits by placing behind the sitter screens of painted scenery, which furnish pleasing back grounds. He specifies also various kinds of artificial illumination, to L-; used in the absence of solar light. {Newton's Joumaly C. S. xx. 430.) According to M. Barnard, Daguerre's iodized plate should be exposed for half a minute to the action of chlorine, mixed with a large proportion of common air; whereby it becomes so sensitive, that the pictorial impression is produced in the short space of time necessary for removing and replacing the screen of the camera. The mercury is afterward employed ; as also the hyposulphite wash. Daguerrotype pic- tures are colored by dusting over them powders of proper hues, which are immediately washed by passing the plate through water. What remains of the color after this ab- lution does not seem in the least to injure the appearance or alter the form of the image. It would seem that those parts of the picture which were at first black, retain, after being washed, a larger proportion of the coloring matter than the lighter parts. Several valuable improvements seem to have been made in Vienna upon the Da- guerrotype process ; and among others, the mode of using chloriodine. The best form of box for applying the chloriodic vapor is square, with its bottom of plate glass, supported a little above the table by feet, a thumb-screw being one of them, in order to give a certain inclination to the glass plate for spreading the chlor- iodine over it uniformly. A sheet of white paper being laid beneath the box, enables the operator to see whether the liquid chloriodine is properly distributed. There is a groove round the top of the box, into which the letlge of the lid fits tight. A thermom- eter is placed in the box. Voigtlatd*s lenses consist of two achromatic object-glasses placed apart ; the first near- est the object, having an aperture of 18 lines ; the second one of 19 lines ; the solar fo- cus of the two is 5J fnches. A system of lenses of so short a focus with so large aper- tures affords from 1 1 to 12 times more illumination than Daguerre's original apparatus did. The finest p)rtraits can be produced in the course of from 10 to 30 seconds with this arranjjement. Such an apparatus, elegantly made in brass, costs only 120 gulden, or about 10 guineas. Voigtland has recently made a camera with two object-glasses, as above arranged, each having an aperture of 37 lines, and a combined focus of 12 inches. By means of this instrument, portraits 5^ inches in size can be made. The landscapes produced in them are very beautiful. Its price is 144 gulden, about 12 guineas. Along with the above apparatus, a box with a bdttom of amalgamated copper is used for applying the vapor of mercury. . By peculiar methods of polishing the silvered copper plate, peculiar tones and tints may be given to the picture. The olive-oil and pumice-powder are indispensable for i«moving the scratches from the plate and to render its surface uniform. If a delicate blue tone be desired, the plate should be a second time polished with sulphuric ether and washed tripoli ; and a third time with dilute nitric acid and Paris red, rubbing the plate lastly with a peace of washleather and crocus. But if a brownish black tone be wished for, a like series of operations is to be gone through, only instead of the ether and tripoli, spirit of ammonia and Vienna lin^e is to be used. 568 DAMASCUS BLADES. DAMASK. 569 To give the plate the utmost sensibility to light, a film of iodine should be given in the first place. If with dry iodine, this should be strewed, then covered with cotton, and lastly with a sheet of paper, and the plate above the last, but not so as to touch it. This may be done also with a solution of 1 part of iodine in 6 of spirits of wine, put into a saucer, which is laid on the bottom of the box, and covered with gauze. The plate is to be removed whenever it has acquired a faint brazen tint. By this means the plate receives the impressions of light so well as to produce good contrasts between the white and the dark places. The application of bromine afterward causes a rapid reception of the image, and occasions the deep black shades of an object. The best form is brome water, made by dissolving the bromine in a little distilled water, and then adding more, when it is wanted, till the solution acquires a straw-yellow color. A delicate thermometer being put into the box, the solution is to be spread uniformly on its glass b*)ttom, the plate being laid on above and covered up, while the time of expo sure must ye counted by seconds, with a clock or watch. If the temperature be 41° F., the time should be 258 seconds. 50^ 230 — 89* 201 — 68* 158 — IT 113 — By attending to these instructions, exact results may be always obtained. A second mode of experimenting is with bromiodine ; prepared by dissolving 1 part of bromine in an alcoholic solution of 5 parts of iodine; and diluting this mixture with water, till it acquires the color of Bavarian beer. The action of this application upon the plate is so rapid as hardly to leave time for consideration. It must be watched ev- ery instant till the dark gold yellow tint appear, when it is ready for the camera. The best time of day for Daguerrotype operations is from an hour after the sun rises till he comes within 45® of the meridian, and not again till he has passed the meridian by 45**. When the sitting is too long, the parts which should be pure white become of a dirty blue tint, and the dark parts become brown. The picture is burnt, so to speak. Chloride of gold applied to the picture has the efiect of fixing and enlivening the tints. A small graie being fixed by a clamp to the edge of a table, the plate is laid upon it with the image uppermost, and overspread evenly with solution of chloride of gold, by means of a fine broad camel-hair brush, without letting any drop over the edge. A spirit lamp is now brought under the plate, and moved to and fro till a number of amall steam bubbles appear upon the image. The spirit lamp must be immediately withdrawn. The remainder of the chloride solution must be poured back into the phia), to be used on another occasion. It is lastly to be washed and examined. This opera- tion has been repeated three or four times with the happiest effect, of giving fixity and force to the picture. It may then be wiped with cotton without injury. By dusting various pigment powders from small cotton-wool dossils npon the picture^ previously coated with an alcoholic solution of copal, and nearly dry, the appearance of a colored miniature has been very successfully imitated. The varnish must be applied delicately with one stroke of a broad brush of badger hair.* DAOTJERREoryPE Engraving. This new art, patented by M. A. F. J. Claudet on the 2l8t November, 1843, is established on the following facts. A mixed acid, consisting of water, nitric acid, nitrate of potash, and common salt, in certain proportions, being poured upon a Daguerreotype picture, attacks the pure silver, forming a chloride of that metal, but does not aft'ect the w^hite parts, which are produced by the mercury of the picture. This action does not last long. Water of ammonia, containing a little chloride of silver in solution, dissolves the rest of that chloride, which is then washed away, leaving the naked metal to be again attacked, especially with the aid of heat. The metallic surface should have been perfectly purified by means of alcohol and caus- tic potass. For the rest of the ingenious but complex details, see Newton's Jtmrnal, C. S., vol. XXV., p. 112. DAPILINE, the same as Inuline, the fecula obtained from elecampane, analogous in many respects to starch. It is not employed in the arts. DAMASCUS BLADES, are swords or scymitars, presenting upon their surface n va- riegated appearance of watering, as white, silvery, or black veins, in fine lines, or fillets; fibrous, crossed, interlaced or parallel, 8. DIAMOND. Since this body is merely a condensed form of carbon, it cannot in a i>iEmical classiHcaiion be ranked among stones; but as it forms in commerce the most precious of the gems, it claims our first attention in a practical treatise on the arts. Diamonds are distinguishable by a great many peculiar properties, very remarkable and easily recognised, both in their rough state, and when cut and polished. Their most absolute and constant character is a degree of hardness superior to Ihatof everj' mineral, whence diamonds scratch all other bodies, and are scratched by none. Their peculiar adamantine lustre, not easy to define, but readily distinguishable by the eye from that of every other gem, is their most obvious feature. Their specific gravity is 3*55. Whether rough or polished, diamonds acquire by friction positive electricity, but do not retain it for more than half an hour. The natural form of diamonds is derivable from an octahe^ dron, and they never present crjstals having one axis longer than the other. Their struc- ture is very perceptibly lamellar, and therefore, notwithstanding their great hardness, they are brittle and give way in the line of their cleavage, afiibrding a direct means of arriving at their primitive form, the regular octahedron. The diamond possesses either single or double refraction, according to its different crys- talline forms ; its refractive power on light is far greater than it ought to be in the ratio of its density ; the index of refraction being 2*44, whence Newton long ago supposed it tc consist of inflammable matter. Its various forms in nature present a circumstance peculiar to this body ; its faces are rarely terminated by planes, like most other native crystals, but they are often rounded off, and the edges between them are curved. When these secondary faces are attentively examined with a lens, we remark that they are marked with striae, sometimes very fine and almost imperceptible, but at others well defined ; and that these striae are parallel to the edges of the octahedron, and consequently to those of the plates that are applied on the primitive faces of this figure. Diamonds are usually colorless and transparent ; when colored, their ordinary tint verges upon yellow, or smoke-yellow, approaching sometimes to black ish-brown. Green diamonds are next to yellow the most comifion ; the blue possess rarely a lively hue, but they are much esteemed in Scotland. The rose or pink diamonds are the most valued of the colored kind, and exceed sometimes in price the most limpid ; though generally speaking the latter are the most highly prized. The geological locality of the diamond seems to be in diluvial gravel, and among con- glomerate rocks; consisting principally of fragments of quartz, or rolled pebbles of quarta mixed with ferruginous sand, which compose sometimes hard aggregated masses. This kind of formation is called cascalho in Brazil. Its accompanying minerals are few in number, being merely black oxyde of iron, micaceous iron ore, pisiform iron ore, fragment? of slaty jasper, several varieties of quartz, principally amethyst. In Mr. Heuland's splendid collection there was a Brazilian diamond imbedded in brown iron ore ; another in the same, belonging to M. Schuch, librarian to the Crown Princess of Portugal ; and in the cabinet of M. Eschwege there is a mass of brown iron ore, containing a diamond in thedrusy cavity of a green mineral, conjectured to be arseniate of iron. From these facts it may be inferred with much probability that the matrix or original repository of th# diamond of Brazil is brown iron ore, which occurs in beds of slaty quartzose micaceouf iron ore, or in beds composed of iron-glance and magnetic iron ore, both of which ar< apparently subordinate in that country to primitive clay slate. The loose earth containing diamonds lies always a little way beneath the surface of the soil, towards tne lower outlet of broad valleys, rather than upon the ridges of the adjoining hills. Only two places on the earth can be adduced with certainty as diamond mines, oi rather districts; a portion of the Indian peninsula, and of Brazil. India has been celebrated from the most remote antiquity as the country of diamonds. Its principal mines are in the kingdoms of Golconda and Visapour, extending from J ^ DIAMOND. 575 Cape Comorin to Bengal, at the foot of a chain of mountains called the Orixa, which appear to belong to the trap-rock formation. In all the Indian diamond soils, these gems are so dispersed, that they are rarely found directly, even in searching the richest spots, because they are enveloped in an earthy crusty which must be removed before they can be seen. The stony matter is therefore broken into pieces, and is then, as well as the looser earth, washed in basins scooped out on purpose. The gravel thus washed is eollected, spread oat on a smooth piece of ground, and left to dry. The diamonds arc now recognised by their sparkling in the sun, and are picked out from the stones. The diamond mines of Brazil were discovered in 1728, in the district of Scrro-do- t>rio. The ground in which they are imbedded has the most perfect resemblance to that of the East Indies, where the diamonds occur. It is a solid or friable conglomerate, consisting chiefly of a ferruginous sand, which encloses fragments of various magnitude of yellow and bluish quartz, of schistose jasper, and grains of gold disseminated with oliffist iron ore ; all mineral matters different from those that constitute the neighboring mountains; this conglomerate, or species of pudding-stone, almost always superficial, occurs sometimes at a considerable height on the mountainous table-land. The most celebrated diamond mine is that of Mandarga, on the Jisitonhonha, in the district of Serro-do-Frio to the north of Rio Janeiro. The river Ji?itonhonha, three times broader than the Seine at Paris, and from 3 to 9 feet deep, is made nearly dry, by drawing the waters off with sluices at a certain season ; and the cascalho or diamond-?ravel is removed from the channel by various mechanical means, to be washed elsewhere at leisure. This cascalho, the same as the matrix of the gold mines, is collected in the dry season, to be searched into during the rainy ; for which purpose it is formed into little mounds of 15 or 16 tons weight each. The washing is carried on beneath an oblong shed, by means of a stream of water admitted in determinate quantities into boxes containing the cas- calho. A negro washer is attached to each box; inspectors are placed at regular dis- tances on elevated stools, and whenever a negro has found a diamond, he rises up and exhibits It. If it weighs 17^ carats, he receives his liberty. Many precautions are taken to prevent the negroes from secreting the diamonds. Each squad of workmen consists of 200 negroes, with a surgeon and an almoner or priest. The flat lands on either side of the river are equally rich in diamonds over their whole surface, so that it becomes very easy to estimate what a piece of ground not yet washed may produce. It is said that the diamonds surrounded with a greenish crust are of the first water, or are the most limpid when cut. The diamonds received in the different mines of the district are deposited once a month in the treasury of Tejuco ; and the amount of what , was thus delivered from 1801 to 1806, may be estimated at about 18 or 19 thousand ca- rats per annum. On the banks of the torrent called Rio Pardo, there is another mine of diamonds. The ground presents a great many friable rocks of pudding-stone, distributed in irregu- lar strata. It is chiefly in the bed of this stream that masses of cascalho occur, pecu- liarly rich m diamonds. They are much esteemed, particularly those of a greenish-blue color. The ores that accompany the diamond at Rio Pardo differ somewhat from those of the washing grounds of Mandanga, for they contain no pisiform iron ore ; but a great many pebbles of slaty jasper. This table land seems to be very high, probably not less than 5500 feet above the level of the sea. Tocaya, a principal village of Minas Novas, is 34 leagues to the northeast of Tejuco in an acute angle of the confluence of the Jigitonhonha and the Rio Grande. In the bed of the streamlets which fall westward into the Jigitonhonha, those rolled white topazes are found which are known under the name of minas novas with blue topazes,and aquamarine beryls. In the same country are found the beautiful cymophanes or cnso- beryls so much prized in Brazil. And it is from the cantons of Indaia and Abaite thai the largest diamonds of Brazil come; yet they have not so pure a water as those of the district of Serro-do-Frio, but incline a little to the lemon yellow. Diamonds are said to come also from the interior of the island* of Borneo, on the banks of the river Succadan, and from the peninsula of Malacca. It is known that many minerals become phosphorescent by heat, or exposure to the sun's light. Diamonds possess this property, but all not in equal decree, and certain precautions must be observed to make it manifest. Diamonds need to be exposed to the sunbeam for a certain time, in order to become self-luminous; or to the blue rays of the prismatic spectrum, which augment still more the faculty of shinin? in the dark. Dia- monds susceptible of phosphorescence exhibit it either after a heat not raised to redness, or the electric discharge. They possess not only a great refractive power in the mean ray of light, but a high dispersive agency, which enables them to throw out the most varied and vivid colors in multiplied directions. Louis de Berquem discovered, in 1476, the art of cutting diamonds by rubbing them 37 576 DIAMOND. against one another, and of polishing them with their own powder. These operations may be abridged by two methods: 1. by availing ourselves of the direction of tlie laminte of the diamond to split them in that direction, and thus to produce several facets. This process is called cleaving the diamond. Some, which appear to be made crystals, resist this mechanical division, and are called diamonds of nature. 2. by sawing the diamonds by means of a very delicate wire, coated with diamond powder: Diamonds take precedence of every gem for the purpose of dress and decoration ; and hence the price attached to those of a pure water increases in so rapid a proportion, that, beyond a certain term, there is no rule of commercial valuation. The lai^est diamond that is known seems to be tliat of the Rajah of Mattan, in the East Indies. It was of the purest water, and weighs 367 carats, or at the rate of 4 grains to a earat^ upward of 8 ounces troy. It is shaped like an egg, with an indented hollow near the smaller end ; it was discovered at Landak about 100 years ago; and though the possession of it has cost several wars, it remained in the Mattan family for 90 years. A governor of Batavia, after ascertaining the qualities of the gem, wished to be the purchaser, and oflFered 150,000 dollars for it, besides two war brigs with their guns and ammunition, together with a certain number of great guns, and a quantity of powder and shot. But this diamond possessed such celebrity in India, being regard as a talisman involving the fortunes of the Rajah and his family, that he refused to part with it at any price. The Mogul diamond passed into the possession of the ruling fatnily of Kabul, as has been invariably affirmed by the members of that family, and by the jewellers of Delhi and Kabul. It has been by both parties identified with the great diamond, now known under the name of the Koim-Nook^ or mountain of light, which was displayed by its present proprietor, her Majesty the Queen, at the recent Great Exhibition. ' It is now being properly cut by skilful Dutch artists, under the charge of Messrs. Garrard, jewellers in London, in order to bring out all its lustre, and remove some superficial specks or clouds. The weight of it has been of old various stated. The diamond possessed, in the time of the traveller Tavernier, by the emperor of Mogul, a kingdom now no more, weighed 279 carats, and was reckoned worth upwards of 400,000/. sterling. It was said to have lost the half of its original weight in the cutting. After these prodigious gems, the next are: — 1. That of the emperor of Russia, bought by the late empress Catharine, which weighs 193 carats. It is said to be of the size of a pigeon's cgz^ and to have been bought for 90,000/., besides an annuity to the Greek merchant of 4000/. It is reported that *he above diamond formed one of the eyes of the famous statue of Sheringan, in the temple of Brama, and that a French grenadier, who had deserted into the Malabar service, found the means of robbing the pagoda of this precious gem ; and escaped with it to Madras, where he disposed of it to a ship captain for 2,000/., who resold it to a Jew for 12,000/. From him it was transferred for a large sum to the Greek merchant. 2. That of the emperor of Austria, which weighs 139 carats, and has a slightly yellowish hue. It has, however, been valued at 100,000/. 3. That of the king of France, called the Regent or Pitt diamond, remarkable for its form and its perfect limpidity. Although it weighs only 136 carats, its fine qualities have caused it to be valued at 160,000/., though it cost only 100,000/. The largest diamond furnished by Brazil, now in possession of the crown of Portugal, weighs, according to the highest estimates, 120 carats. It was found in the streamlet of Abaite, in a clay-slate district. The diamonds possessed of no extraordinary magnitude, but of a good form and a pure water, may be valued by a certain standard rule. In a brilliant, or rose-diamond of regular proportions, so much is cut away that the weight of the polished gem does not exceed one half the weight of the diamond in the rough state ; whence the value of a cut diamond is esteemed equal to that of a similar rough diamond of double weight, exclusive of the cost of workmanship. The weight and value of diamonds are reckoned by carats of 4 grains each ; and the comparative value of two diamonds of equal quality but different weights, is as the squares of these weights respectively. The average price of rough diamonds that are worth working is about 2/. for one of a single carat ; but as a polished diamond of one carat must have taken one of 2 carats, its price in the rough state is double the square of 2/., or 8/. Therefore, to estimate the value of a wrought diamond, ascertain its weight in carats, double that weight, and multiply the square of this product by 21. Hence, a wrought diamond of 1 carat is worth 2 — 3 4 5 6 £ 8 32 72 128 200 288 DIAMOND. 577 of 7 carats is worth 892 8 — 612 9—612 10 — 800 Tz:::z^::r ^^\^----^. vr7,r..^ojz KaifntbTrtfVuth^:; cuUirXt wZ^"''• «"^^/%f,<^.«»"«tive gems, but for more useful purposes, as for cutting glass by the glazier, and all kinds of hard stones by the lapidarV. vaUons nndT7V T ^}^^%\^''^^^^^ we possess some very interesting obser- bro X t^ /i'f '"^^ Dr Wollaston. He remarks, that the hardest substances Alnnf r. a\TK P"""* '''•'"^t. ^^^"^ ^"^«^^' b"<^ ^^ «ot cut it, and that diamonds alone possessed that property; which he ascribes to the peculiarity of its crystalirtLn in rounded faces and curvilinear edges. For glass-cutting, thoseVough dfamonds ar^ always selected which are sharply crystallizedrhence callld diamond sparks but ciU dmrnonas are never used. The inclination to be given to a set diamond fncuit'ineeU^ IS comprised w.th.n very narrow limits; and it ought, moreoverto be moveHn 1^ direction of one of its angles. The curvilinear edge adjoining the curved f^es ente. n* as a wedge into the furrow opened up by itself, thus tends to sepa^e the Srts of hf glass ; and in order that the crack which causes the seoaratinn of fhlV;?^. ^ !• i 3:is'%fn"'/'^''^'"rt'"r '^ ""''' al-st Ve^r/nd^riaf o'^thT^fL^^^^^^^ wJ. . I r'^K PT^ ^^^ '^^""'"^ ^y^" experiment. If, by suitable cutting with the wheel, we make the edge* of a spinel ruby, or corundura-telesie fsannhire curvi np«r 5elrreL\\"d \ r U'thl^^^^^ f"" ""' T'''^'' as weira'a^gS^^dfronr^ not seem to exceed the two-hundredth of an inch^ " ^"^^""^ penetrates, does ^:^l^^^^i:i^:^^^ - ^-^ choice of rough the coat be smooth and bright, with a liule tincture of%Teen1n'jr?f t Lv T ^ and seldom proves bad, but iT there is a mixture of ydlow'^kS gretn then b wareT/u- It IS a soft greasy stone, and will prove bad. ^ ' ^'^^ ^^ ^^' li the stone has a rough coal, so that you can hardlv sep fhrniKrh -t o„^ ♦», * u white and look as {( it wpre rou-h bv art \m\ M*>«r «r fl^ through it, and the coat be the heart of the stone to be white (and if IherrbTanv black slt^l^^^^^^^ ""^^ ''^•'"'•^ it, they may be discovered by a true eye althou-h th^Lt .r tK^ f' or flaws, or veins la such stones are generally goUand clear. ° '^^' °^ '^' ''^'^" ^^ '^^ ^^"^^^^ ^^^ If a diamond appears of a greenish bri^^ht coat rp«pmKKno. » • *• inclining ,o black it generally provi hari, a^d sel^,^ bad^ ".JTI "^ ^l^^" «i'^ known to have been of the Brst water, and seldom wo^^.h.;, ,K °? t'»™.,'«" tinct^eof ,e.lowsee.os to be .nixed ^ith V;orj;CnT oriu^t^ a'^'e^' Sa"5 All diamonds of cinnamon color are dubious- hut iT ^r <. k..:„i.* . • i {:::^rclT::?;u::Lr tt sotf "'• ?^ surface or in their intPrinr A i^T **'^°^"i^" grams, that sometimes occur on their ...4erieeUr^:U^et?rt«i:t::r^^^^^^^^^ 578 DIAMOND DUST. crystals. When this happens, the stone does not readily cut and polish, and is there- fore of inferior value. In the cut and polished gem, the thickness must always bear a certain proportion to the breadth. It must not be too thin nor thick; for, when too thin, it loses much of its fire, and appears not unlike glass. The term carate is said to be derived from the name of a bean, the produce of a speciee of eri/thina, a native of the district of Shangallas, in Africa, a famous mart of gold-dust. The tree is called kuara, a word signifying sun in the language of the country; because it bears flowers and fruit of a flame color. As the dry seeds of this pod are always of nearly uniform weight, the savages have used them from time immemorial to weigh gold. The beans were transported into India, at an ancient period, and have been long employed there for weighing diamonds. The carat of tlie civilized world is, in fact, an imaginary weight, consisting of 4 nominal grains, a little lighter than 4 grains troy {jpoids de marc); it requires 74 carat grains and l to equipoise 72 of the other. In valuing a cut diamond, we must reckon that one half of its weight has been lost in the lapidary's hands; whence its weight in this state should be doubled Wfore we calculate its price by the general rule for estimating diamonds. The French multinly by 48 the square of this weight, and they call the product in francs he value of "the di8.mond. Thus, for example, a cut diamond of 10 carats would be worth (10 X ?)' X 48:^19,200 francs, or 768/., allowing only 25 francs to the pound sterling. The diamond mines of Braizil have brought to its government, from the year 1730 till 1814,3,023,000 carats; being at the average rate annually of 36,000 carats, or a little more than 16 lbs. weight. They have not been so productive in the later years of that period; for, according to Mr. Mawe, between 1801 and 1806, onl> 115,675 carats were obtained, being 19,279 a year. The actual expenses incurred by the government, during this interval, was 4,419,700 francs; and, deducting the pro- duction in gold from the washings of the diamond gravel, or cascalho, it is found that the rough diamonds cost in exploration, per carat, 38 francs 20 c, or nearly 31*. British money. The contraband is supposed to amount to one third of the above legitimate trade. Brazil is almost the only country where diamonds are mined at the present day ; it sends annually to Eiurope from 25 to 30 thousand carats, or from 10 to 16^ lbs. DIAMONDS, cuffing of. Although the diamond is the hardest of all known sub- stances, yet it may be split by a steel tool, provided a blow be applied ; but this requires a perfect knowledge of the structure, because it will only yield to such means in certain directions. This circumstance prevents the workmi-i from forming faceltes or planes generally, by the process of splitting; he is therefore obliged to resort to the process of abrasion, which is technically called cutting. The process of cutting is effected by fixing the diamond to be cut on the end of a stick, or handle, in a small ball of cement, that part which is to be reduced being left to project. Another diamond is also fixed in a similar manner; and the two stones being rubbed against each other with considerable force, they are mutually abraded, flat surfaces, or facettes, being thereby produced. Other faceltes are formed by shifting the diamonds into fresh positions in the cement, and when a sufficient number are produced, they are fit for polishing. The stones, when cut, are fixed for this purpose, by imbedding them in soft solder, contained in a small copper cup, the part, or facelle, to be polished, being left to protrude. A flat circular plate of cast-iron is then charged with the powder produced during the abrasion of the diamonds ; and by this means a tool is formed which is capable of producing the exquisite lustre so much admired on a finely-polished gem. Those diamonds that are unfit for working, on account of the imperfection of their lustre or color, are sold, for various purposes, under the technical name of Bort. Stones of this kind are frequently broken in a steel mortar, by repeated blows, until they are reduced to a fine powder, which is used to charge metal plates, of various kinds, for the use of jewellers, lapidaries, and others. Bort, in this state of preparation, is incapable of polishing any gems ; but it is used to produce flat surfaces on rubies and other precious stones. Fine drills are made of small splinters of bort, which are used for drilling small boles in rubies, and other hard stones, for the use of watch-jewellers, gold and silver wire- drawers, and others, who require very fine holes drilled in such substances. These drills are also used to pierce holes in china, where rivets are to be inserted ; also for piercing holes in artificial enamel teeth, or any vitreous substances, however hard. DIAMOND DUST. The demand for diamond dust within a few years has in- creased very materially, on account of the increased demand for all articles that are wrought by it, such as cameos, intaglios, &c. Recently there has been a discovery made of the peculiar power of diamond dust upon steel ; it gives tlie finest edge to all i Di AS'IASE. 579 kinds of cutlery, and threatens to displace the hone of Hunffarv It is wpTI Vn^w,, ,u * ofZ'ZV ?"T2 (!'-,i-^<^-^ -'-tance in naturefthf dT^t is ^ a'd on thTteerh throrh ThT '"^'^ fu^'T^ ""^ ^^•"^ P^^^«"^« the instrument from making its wav DIAMOND MICROSCOPES were first suff^est^^d bv r>r r- «.;.,„ ^ i, ferent crystalline forms of the diamond prob»bIvth/Lfj!S ?"S. "" ." ^''■ the only ones thai will give a sinervi.'ion ft will ■ °<"*''«'''»n »"<) ihe o"!)* are grind iamond lenses pwLn>Tbo rbeca .sI wrfiZ? °?"^ ''%°'^"'"u'''''. »? aberration, and because it saves the trouble of grTniine ofe shifT.l.* '""^ 'P^"'^ pletin^g a double eon'veJof ejua, r^C^U^^ZZO:^-^::^ :: :Z: ture of ,tj of an ,nch w,th distinctness upon o,?,'q„e object^ and i^ entire diameter ilrration by the interpofiUon F. y"a sil' e „t,S tlZZn "l'^"' r'""""' ture of it with an eyeglass, is evident We thus bli^ 1' '!'"''"''»' 'ookmg at a pio- ' mXi^FR -- --.^/y an^t U^^fral\::;ro7o Jetr' '■"-' ""^'^'"^ without thraid of J^vn,' ^ 'i^P'^' ^"'^ '" ^'•°"^'^' entirely by the weaver! onlVilft^vt « tZs/lSL-rv^arw-hentror h^ ^^fr:^';^^'^ T^^ ^ are generally five-leaf tweehthatls to J^^ mounting ,s called diaper. Diapers woof, and is^aiseJ anro^l^ur'e a erlven ^Uh'th'Tfth "Th""'"^'" ^'^'^ "^ cessively, formin- diagonals at A^° ,, nnn t h« «i Ti u ■' ^^'^ '^ "^^'"^ ^'^^^^ sue- is called' 'the broken tC The lat"^" s Ven^^nT J notT'' '' ^ ^i"^^^^' "^'^^ n,anufacture of diaper. The reason of n-pf^r^.i'. if u ^'^'^--^^lly' ^dopted in the where ornaments are^o be fLedtrveryoTvrusVhe^h^^^^^^ '" r' ^^'"^^^ ^"'^•^^• flushing to give the appearance of ohi:nM;«rr ^'^e ,^J.«'e dependmg upon reversed destroy much of theXrand Lt Ha '«%% ren?auty"o7'the'f:b'' ^^^'k"?^' tweel, on the contrary, restores to the tweeled cicnh a 'real sin^ laHtv'r ' ^''*^"'* plam, or alternately interwoven fabrics, and at the samP .1 ^^ ""^ appearance to producing ornaments by reversin^^ the flushing Th^^f T . r-^T""? ^^^ ^^^^''^^ °^ will be found describeJunder Textile Fabr"S. "^'''' ^'"^' "^ '""""''^^^ '^^«'* DIASTASE. This curious substance extra*«tpH Kv nrof». e ^ . , cipitated from that infusion bv alcoh^ras isTe.cKbL u^^^^ ""'^'^ "^"^'v*"^ ^'^' made the subject of new researches by m! Guer7n Varrv Vh?'^^''^^^^^ **-" from his interesting experiments are the foIlowiJicr 1 ^' ^^ conclusions deducible tato s^arcVot ^f t^^ o?^;:,^^ iot'^xSelri? T'? ^" ^''^ ''' '-'' ^' ^ in the course of 63 days under 'a telTeVre^Ta^^l^g^'l?^^^^^^^ -^«^-- paft-s Tf^stai'rrb'u :r r: erp:ir.!;\:ra:h^-^ ^^ '^- -r {- ^^^^^ ^^ ^^- which bursts them into' a pa L^ l^fol WsXt d^^l"'"^ "^^ '^^' ""^'^^ ^«' ^«'«' germination, towards eliminating the te^^mPnu of !h .^''k "" P*'^ '? ^^^ P'«"^^« ^^ rior portion 'into sugar, and a gumL^^^lttr^sLlfe^ ^ptnU. ^""'"°^"^ ''' ^^'" 580 DIES FOR STAMPING. DIES FOR STAMPING. 581 8. Diastase liquefies and saccharifies the paste of starch without absorption or disen- gagement of gas ; a reaction which takes place equally in vacuo as in the open air. 4. 100 parts of starch made into a paste with 39 times their weight of water, mixed with 6"13 parts of diastase dissolved in 40 parts of water, and kept for an hour between 140° and 149^ Fahr., afforded 86*91 parts of sugar. . 5. A paste containing 100 parts of starch, and 1393 parts of water, put in contact with 12-25 parts of diastase dissolved in 367 parts of cold water, having been main- tained at 68° Fahr. during 24 hours, produced 77*64 parts of sugar. 6. The preceding experiment, repeated at the temperature of melting ice, afforded at the end of 2 hours, 11*82 parts of sugar. 7. T-he most favorable proportions and circumstances for the production of a great quantity of sugar, are a slight excess of diastase or barley malt (at least 25 per cent, of the latter), about 50 parts of water to one of starch, and a temperature between 140° and 149° Fahr. It is of the greatest consequence for the saccharification to take place as speedily as possible, so that the sugar produced may not be left in contact with much gummy matter {dextrine), in which case the diastase will not convert the latter into sugar. In fact, the liquefaction and saccharification should proceed simultane- ously. 8. The sugar of starch prepared either with diastase, or sulphuric acid, crystallizes in cauliflowers, or in prisms with rhomboidal facets. It has the same composition as sugar of grapes. 9. Diastase even in excess does not saccharify the gummy matter dissolved in the water along with the starch-sugar, but when the gum is insulated, it is convertible almost entirely into sugar. 10. Gum arable, cane sugar, and beer yeast, suffer no change from diastase. 11. A watery solution of diastase readily decomposes on keeping, either in contact or out of contact of air. 12. When starch-sugar, whether obtained by means of diastase or sulphuric acid, is submitted to the spirituous fermentation, the sum of the weights of the alcoljol, car- bonic acid, and water of crystallization of the sugar, is less than the weight of the sugar by about 3| per cent This difference proceeds in a great mensure from the form- ation of some acetic acid, lactic acid, volatile oil, and probably aome other unknown products in the act of fermentation. DIDYM. A new metal, found in oxide of cerium, and so called as being associated in that ore as a ttoin brother of lanthanum. DIES FOR STAMPING. (Coins, Fr. ; Munzstampeln, Germ.) The fii-st circum- stance that claims particular attention in the manufacture of dies, is the selection of the best kind of steel for the purpose, and this must in some measure be left to the expe- rience of the die-former, who, if well skilled in his art, will be able to form a tolerably correct judgment of the fitness of the metal for the purpose, by the manner in which it works upon the anvil. It should be rather fine-grained than otherwise, and above all things perfectly even and uniform in its texture, and free from spots and patches finer or coarser than the general mass. But the very fine and uniform steel with a silky frac- ture, which is so much esteemed for some of the purposes of cutlery, is unfit for our present purpose, from the extreme facility with which it acquires great hardness by pres- sure, and its liability to cracks and flaws. The very coarse-grained or highly crystalline steel is also equally objectionable ; it acquires fissures under the die-press, and seldom admits of being equally and properly hardened. The object, therefore, is to select a steel of a medium quality as to fineness of texture, not easily acted upon by dilute sulphuric acid, and exhibiting a uniform texture when its surface is washed over with a little aqua-fortis, by which its freedom from pins of iron, and other irregularities of composi- tion, is sufficiently indicated. The best kind of steel being thus selected, and properly forged at a high heat into the rough die, it is softened by very careful annealing, and in that state, having been smoothed externally, and brought to a table in the turning lathe, it is delivered to the engraver. The process of annealing the die consists in healing it to a bright cherry red, and suf- fering it to cool gradually, which is best eflected by bedding it in a crucible or iron pot of coarsely-powdered charcoal, that of animal substances bemg generally preferred. In this operation it is sometimes supposed that the die, or at least its superficial parts, be- comes super-carbonized, or highly-converted steel, as it is sometimes called ; but expe- rience does not justify such an opinion, and I believe the composition of the die is scarcely, certainly not materially, affected by the process, for it does not remain long enough in the fire for the purpose. The engraver usually commences his labors by working out the device with small steel tools, in intaglio ; he rarely begins in relief (though this is sometimes done) ; and having ultimately completed his design, and satisfied himself of its general effect and correctness, by impressions in clay, and dabs, or casts in type metal, the die is ready for the important operation of hardening, which, from various causes, a few of which I shall enumerate, is a process of much risk and diflliculty ; for should any accident now occur, the labor of many months may be seriously injured, or even rendered quite useless. The process of hardening soft steel is in itself very simple, though not very easily explained upon mechanical or chemical principles. We know by experience that it is a property of this highly valuable substance to become excessively hard, if heated and suddenly cooled ; if, therefore, we heat a bar of soft malleable and ductile steel red hot, and then suddenly quench it in a large quantity of cold water, it not only becomes hard, but fragile and brittle. But as a die is a mass of steel of considerable dimen- sions, this hardening is an operation attended by many and peculiar diflBculties, more especially as we have at the same time to attend to the careful preservation of the engraving. This is effected by covering the engraved face of the die with a protecting face, composed of fixed oil of any kind, thickened with powdered charcoal : some persons add pipe-clay, others use a pulp of garlic, but pure lamp-black and linseed oi. answer the purpose perfectly. This is thinly spread upon the work of the die, which, if requisite, may be further defended by an iron ring ; the die is then placed with its face downwards in a crucible, and completely surrounded by powdered charcoal. It u heated to a suitable temperature, that is, about cherry red, and in that state is taken out with proper tongs, and plunged into a body of cold water, of such magnitude as not to become materially increased in temiwr tture ; here it is rapidly moved about, until all noise ceases, and then leH in the water till quite cool. In this process it should produce a bubbhng and hissmg noise; if it pipes and sings, we may generally apprehend a crack or fissure. No process has been found to answer better than the above simple and common mode of hardening dies, though others have had repeated and fair trials. It has been proposed to keep up currents and eddies of cold water in the hardening cistern, by means of dehvery.pipes, commg from a height ; and to subject the hot die, with its face upper- most, to a sudden and copious current of water, let upon it from a large pipe, supplied from a high reservoir ; but these means have not in any way proved Ejore successfui, either m saving the die or in giving it any good qualities. It will be recollected, from the form of the die, that it is necessarily only, as it were, case-hardened ; the hardest strata being outside, and the sofYer ones within, which envelop a core, something in the manner of the successive coats of an onion ; an arrangement which we sometimes have an opportunity of seeing displayed in dies which have been smashed by a violent blow. The hardening having been effected, and the die being for the time safe, ^ome fur- ther steps may be taken for its protection ; one of these consists in a ^ery mild kind of tempering produced by putting it into water, gradually raised to tiie boiling point, till heated throughout, and thei suffering it gradually to cool. This operation rendera the die less apt to crack in very cold weather. A great safeguard is also obtained by thrusting the cold die into a red-hot iron ring, which just fits it in that state, and which, by contracting as it cools, keeps its parts together under considerable pressure, pre! venting the spreading of external cracks and fissures, and oflen enabling us to employ a split or die for obtaining punches, which would break to pieces without the protecting If the die has been successfully hardened, and the protecting paste has done its duty, by preserving the face from all injury and oxydizement, or burning, as it is usually called. It IS now to be cleaned and polished, and in this state constitutes what is technically called a matrix; it may, of course, be used as a multiplier of medals, coins, or impressions, but it is not generally thus employed, for fear of accidents happening to It in the coming press, and because the artist has seldom perfected his work upon It m this state. It is, therefore, resorted to for the purpose of finishing a punch, or steel impression for relief. For this purpose a proper block of steel is selected, of the same quality, and jyith the same precautions as before, and being carefully annealed, or softened, is turned like the matrix, perfectly true and flat at the bottom, and obtusei; conical at top. In this state, its conical surface is carefully compressed by pow- erful and proper machinery upon the matrix, which, being very hard, soon allows it to receive the commencement of an impression; but in thus receiving the impression, it becomes itself so hard by condensation of texture as to require, during the o^ration, to be repeatedly annealed, or softened ; otherwise it would split into small superficial fis- Wres, or would injure the matrix ; much practical skill is therefore required in taking this impression, and the punch, at each annealing, must be carefully protected, so that the work may not be injured. j y t Thus, afler repeated blows in the die-press, and frequent annealing, the impressio* 582 DIGESTER. from the matrix is at length perfected, or brought completely up, and having been retouched by the engraver, is turned, hardened, and collared, like the matrix, of which It IS now a complete impression in relief, and, as we have before said, is called a punch. This punch becomes an inexhaustible parent of dies, without further reference to the original matrix ; for now by impressing upon it plusfs of soft steel, and by pursuing with them an exactly similar operation to that by which the punch itself was obtained, we procure impressions from it to any amount, which of course are fac-similes of the matrix, and these dies being turned, hardened, polished, and, if necessary, tempered, are employed for the purposes of coinage. The distinction between striking medals and common coin is very essential, and the work upon the dies is accordingly adjusted to each. Medals are usually in very high relief, and the effect is produced by a succession of blows; and as the metal in which they are struck, be it gold, silver, or copper, acquires considerable hardness at each stroke of the press, they are repeatedly annealed during the process of bringing them up. in a beautiful medal, which Mr. Wyon some time since completed for the Royal Navy College the obverse represents a head of the King, in very bold relief; it required thirty blows of a very powerful press to complete the impression, and it was necessary to anneal each medal afler every third blow, so that they went ten times into the fire *or that purpose. In striking a coin or medal, the lateral spread of the metal, which Otherwise would ooze out as it were from between the dies, is prevented by the applica- tion or a steel collar, accurately turned to the dimensions of the dies, and' which, wnen lelt plain, gives to the edge of the piece a finished and polished appearance; it is •ometimes grooved, or milled, or otherwise ornamented, and occasionally lettered, im which case it is made in three separate and moveable pieces, confined by a rin?, into which they are most accurately fitted, and so adjusted that the metal may be forced intc the letters by its lateral spread, at the same time that the coin receives the blow of the screw-press. Coins are generally completed by one blow of the coinins-press. These presses arc worked in the Royal Mint by machinery, so contrived that they shall strike, upon an average, sixty blows in a minute; the blank piece, previously properly prepared and an- nealed, being placed between the dies by part of the sa-ne mechanism. The number of pieces which may be struck by a sinele die of good steel, properly hardened and duly tempered, not unfrequently amounts at the Mint to between three and four hundred thousand, but the average consumption of dies is of course much greater owing to the variable qualities of steel, and to the casualties to which the dies are liable : thus, the upper and lower die are often violently struck together, owin<' to an error m the layer-on, or in that part of the machinery which ought to put the bla'nk into Us place, but which now and then fails so to do. This accident very commonly arises from the boy who supermtends the press neglecting to feed the hopper of the layer-on with blank pieces If a die is too hard, it is apt to break or split, and is especially sub- jeet to fissures, which run from letter to letter upon the edse. If too soft, it swells, and the collar will not rise and fall upon it, or it sinks in the centre, and the work becomes distorted and faulty. He, therefore, who supplies the dies for an extensive coinage has many accidents and difliculties to encounter. There are eieht presses at the Mint fre- quently at work for ten hours each day, and the destruction of eight pair of dies per day (one pair for each press) may be considered a fair average result, though they much more frequently fall short of, than exceed this proportion. It must be remembered that each press produces 3600 pieces per hour, but, making allowance for occasional stoppat'es we may reckon the daily produce of each press at 30,000 pieces; the eight pressesl there- fore, will furnish a diurnal average of 240,000 pieces. DIGESTER is the name of a strong kettle or pot of small dimensions, made very strong, and mounted with a safety valve in its top. Papin, the contriver of this appa- ratus, used It for subjecting bones, cartilages, &c. to the solvent action of high-pressure steam, or highly heated water, whereby he proposed to facilitate their digestion in the stomach. This contrivance is the origin of the French cookery pans, called uuloclaves, because the lid is self-keyed, or becomes steam-tight by turning it round nnder clamps or ears at the sides, having been previously ground with emery to fit the edge of the pot exactly. In some autoclaves the lid is merely laid on with a fillet of Unen as a lute, and then secured m its place by means of a screw bearing down upon its fentre from an arched bar above. The safety valve is loaded either by a weight placed rertically upon it, or by a lever of the second kind pressing near its fulcrum, and acted upon by a weight which may be made to bear upon any point of its graduated arm. ^ Chevreul has made a useful application of the digester to vegetable analysis. His instrument consists of a strong copper cylinder, into which enters a tight cylinder of DISTILLATION. 583 silver having its «dge turned over at right angles to the axis of the cylinder, so as to form the rim of the digester. A segment of a copper sphere, also lined with silver fitops the aperture of the silver cylinder, being applied closely to ita rim. It has a conical valve pressed with a spiral spring, of any desired force, estimated by a steelyard, ihis spring is enclosed within a brass box perforated with four holes; which mav be screwed into a tapped orifice in the top of the digester. A tube screwed into another hole serves to conduct away the condensable vapors at pleasure into a Woulfe's apparntua ^ DIMITY is a kind of cotton cloth originally imported from India, and now manu- factured in great quantities in various parts of Britain, especially in Lancashire. Dr Johnson calls It dimmity, and describes it as a kind of fustian. The distinction between fustian and dimity seems to be, that the former designates a common tweeled cotton cloth of a stout fabric, which receives no ornament in the loom, but is most frequently dyed after being woven. Dimity is also a stout cotton cloth, but not usually of so thick a texture; and is ornamented in the loom, either with raised stripes or fancy fiirures. 18 seldom dyed, but usually worn white, as for bed and bed-room furni tine. The striped dimities are the most common, they require less labor in weaving than the others; and the mounting of the loom being more simple, and consequently less expen- sive they can be sold at much lower rates. See Textile Fabrics, for particular details of the plan of mounting them. ^ v.«.»»o DISINFECTION OF CLOTHING, (JW. Davison arul SymingtorCs patent proces A —The absorption of noxious effluvia by clothes or soft and porous articles of inerchan- ^is'sub'ecr'' ^•^cognised as a fact by men who have directed special attention to The use of the various liquid disinfectants, which have of late been proposed, is not applicable to articles of clothing; and the common practice of baking clothes in ovens 18 liable to lead to their destruction, owing to the impossibility of regulating the tem- perature to which It 18 necessary to expose them. The only plan which combines economy with certainty of disinfection, is that which has been patented by Messrs. Davison and Synriington, and which is now extensively employed in various manu- factures. Ihi8 plan consists in exposing the articles of clothing in a large chamber to rapid currents of air heated to a temperature insufficient to iniure them i e varvin^ from 20po to 250O. We have had an 'opportunity of witnessing"' this proT;^ a" ap^lle! to certain branches of manufacture, and the results were of the most satisfactory kind. In the case of infected clothing. ,t is obvious, that while a high temperature tJnds to destroy the animal poisons, a rapid current of air, constantly passing through the chamber tends to carry them off. The temperature of the current of air can be so^egulatedthai common albumen is speedily dried into a yellow transparent solid, without loagulation. or if necessary, the heat may be increased from 400° to 500^, according to the nature of the articles which are exposed Dr. Copland has already directed the attention of the profession to this process, and observes that, "the great advantage of this method IS Its easy applicability to all kinds, and to any number of objects and articles without njury to their textures or fabrics." From an inspection of one of these chambers, when tl.e temperature of the current of air was 116^, we can state that the process of Messrs. Davison and Symington for the drying and disinfecting of the clothing of cholera and fever patients, will l>e far more efficacious than the common plan of washino- „„d bakin.. In our opinion, an apparatus of this kind, fitted up in large hospital^ intirmariet prisons and workhouses, as well as all quarantine stations, would be admirably adapted to prevent the diffusion of infectious diseases. ^ «u«ptea DISTILLATION (Eng. and Fr. ; Branntuevnhrennerei, Germ.) means, in the commer- cial languaffe of this countrj', the manufacture of intoxicating spirits; under which we comprehended the four processes, o( mashing the vegetable materials, roo//ng the wori^ exciting the vinous /crm^/a/ton and separating by a peculiar vessel, called a stilL Xhi alcohol combined with more or less water. This art of evoking the fiery demon of drunkenness from his attempered state in wine and beer, was unknown to the ancient Greeks and Ronrians. It seems to have been invented by ihe barbarianTof the north rf Europe, as a solace to their cold and humid clime; and was first made known to lh* sou hern nations m the writmgs of Arnoldus de Villa Nova, and his pupil, Raymond Lully of Majorca who declares this admirable essence of wine to be an emanat on of the Divmity, an element newly revealed to man, but hid from antiquity, because the h ,, man race were then too young to need this beverage, destined to ?eviv; Te energii of modern decrepitude. He further imagined that the discovery of this aqua rii7 coa taming 45 per cent, of absolute alcohol, (= ^9^ of British proof,) the following ^uan- Wheat, 40 to 45 pounds of spirits ; rye, 36 to 42; barley, 40; oats, 36 ; buckwheat, 40; maize, 40. The mean of the whole may be taken at 40 pounds, equal to 41 gallons imperial, of 0-9427 specific gravity = 3-47 gallons, at excise proof. The chief difference in these several kinds of corn consists in their different bulks under the same weight; a matter of considerable importance ; for since a bushel of oats weighs little more than the half of a bushel of wheat, the former becomes for some purposes less convenient in use than the latter, though it affords a good spirit. Barley and rye are the species of grain most commonly employed in the European distilleries for making whiskey. Bariey is mostly taken either partly or altogether ia the malted state; while the other corns are not malted, but merely mixed with a certain propor ion of bariey malt to favor the saccharine fermentation in the mashing. It is deemed preferable to use a mixture of several sorts of grain, instead of a single one; for example, wheat with barley and oats ; or barley with rye and wheat; for the husks of the oats diffused through the wheat flour and rye meal keep it open or porous when mashed, and thus favor the abstraction of the wort ; whUe the gluten of the wheat tends to convert the starch of the barley and oats into sugar. When the whole of the grain, however, is malted, a much more limpid wort is obtained than from a mixture of malt with raw gram ; hence the pure malt is preferable for the ale and porter brewer, while the mixture affords a larger product, at the same cost of materials to the distiller. Whea barley is the only gram employed, from one third to one sixth of malt is usually mixed with It; but when wheat and rje are also taken, the addition of from one eighth to one sixteenth of bar ey mall is sufficient. Oats are peculiariy proper to be mixed with wheaL to keep the meal open in the mashing. The following are the proportions used by some experienced Scotch distillers. 250 bolls, containing 6 bushels each, being used for a mashing, consist of. 25 bolls of oats, weighing 284 lbs. per boll, or 47| lbs. per bushel: 42 malt 240 40 25 rve 320 53 1 158 250 barley 320 53i mean 48| From each boll, weighing 291 lbs., 14 imperial gallons of proof whiskey are obtained on an average; equivalent to 11-2 gallons at 25 over proof. The malting for the distilleries is to be conducted on the same principles as for the breweries, but the malt ought to be lightly kiln-dried, and that preferably at a steam heat, instead of a hre, which is apt to give an empyreumatic smell to the grain that passes into tlie spirit? For ruch persons, indeed, as relish the smell of burned turf, called i.eat-reek m Scotland, the malt should be dried by a turf fire, whereby the whiskey will acquire that peculiar odor. ^ But this smell, which was originally prized as a criterion of whiskey made from pure malt, moderately fermented and distilled with peculiar cire, has of late years lost its value, since the artifice of impregnating bad raw grain whiskey with peat-smoke has been extensively practised. Dr. Kolle, in his treatise on making spirits, describes a malting kiln with a copper plate heated with steam, 18 feet long, and 12 feet broad, on which a quantity of malt bein? spread thm, is changed every 3 or 4 hours, so that in 24 hours he turns out upwards of 28 cwt. of an excellent and well kilned article. The malt of the distiller should be as pale as possible, because with the deepening of the color an empyreumatic principle is When Indian corn is the subject of distillation, it must be malted in the same way as described in the article Beer. According to Hermstaedt, its flour may be advan- tageously mixed with the crushed malt in the mash tun. But its more complete dissolu- tion may be accomplished by Siemen's mode of operating upon potatoes, presently to be 1. Mashing. Barley and raw grain are ground to meal by millstones, but malt is mereij crushed between rollers. If only one tenth or one eighth of malt be used with nine tenths or seven eighths of bariey, some husks of oats are added, to render the mash raixture more drainable. When 40 bushels of bariey and 20 of malt form one mashing, from 600 to 700 gallons of water, heated to 150° F., are mixed with these 60 bushels in the mash tun, and carefully incorporated by much manual labor with wooden oars, or in great concerns by the mechanical apparatus used in the breweries. This agitation must be continued for 2 or 3 hours, with the admission from time to time of about 400 additional gallons of water, at a temperature of 190°, to counteract the cooling of the materials. But since the discovery of diastasey as the best, heat for saccharifying starch is shown to be not higher than 160° F., it would be far better to mash in a tun, partially, at least, steam incased, whereby we could preserve the temperature at the appropriate degree for gene- rating the greatest quantity of sugar. If the wort be examined every half-hour of the mashing period, it will be found to become progressively sweeter to the taste, thinner in appearance, but denser in reality. The wort must be drawn off from the grains whenever it has attained its maximum density, which seldom exceeds 150 lbs. per barrel ; that is, jt = 1*42, or 42 '360 per cent. As the corn of the distiller of raw grain has not the same porosity as the brewer's, the wort cannot be drawn off from the bottom of the tun, but through a series of holes at the level of the liquor, bored in a pipe stuck in at the corner of the vessel. About one third only of the water of infusion can thus be drawn off from the pasty mass. More water is therefore poured on at the temperature of 190°, well mixed by" agitation for half an hour, then quietly infused for an hour and a half, and finally draws off as before. Fully 400 gallons of water are used upon this occasion, and nearly as much liquor may be drawn off. Lastly, to extract from the grains everything soluble, about 700 gallons of boiling hot water are turned in upon them, thoroughly incorpo- rated, then left quietly to infuse, and drawn off as above. This weak wort is commonly reserved for the first liquor of the next mashing operation upon a fresh quantity of meal and malt. The English distiller is bound by law to make his mixed worts to be let down into the fermenting tun of a specific gravity not less than 1*050, nor more than 1 090; the Scotch and Irish distillers not less than 1*030, nor more than 1*080; which numbers are called, gravity 50, 90, 30, and 80, respectively. With the proportion of malt, raw grain, and water, above prescribed, the infusion first drawn off may have a strength = 20 per cent. = spec. grav. 1*082, or 73 lbs. per barrel ; the second of 50 lbs. per barrel, or 14 per cent. ; and the two together would have a strength of 61*2 lbs. per barrel = 17 per cent., or spec. grav. 1*070. From experiments carefully made upon a considerable scale, it appears that no more than four fifths of the soluble saccharo-starchy matter of the worts is decomposed in the best regulated fermen- tations of the distiller from raw grain. For every 2 lbs. so decomposed, 1 lb. of alcohol, spec. grav. 0*825, is generated ; and as every gallon of spirits of the spec. grav. 0*909 contains 4*6 lbs. of such alcohol, it will take twice 4*6 or 9'2 lbs. of saccharine matter tc produce the said gallon. To these 9*2 lbs., truly transmuted in the process, we must add one fifth, or 1*84 lbs., which will raise to 11*04 the amount of solid matter employed in producing a eallon of the above spirits. Some distillers mash a fourth time ; and always use the feeble wort so obtained ia mashing fresh grain. 2. As the imperfect saccharine infusion obtained from raw grain is much more aces- cent than the rich sugary solution got from malt in the breweries, the distiller must use every precaution to cool his worts as quickly as possible, and to keep them clear from any acetous taint. The different schemes of cooling worts are considered under Beer and Refrigeration. As the worts cool, a quantity of starchy matter is precipitated, but it is all carefully swept along into the fermenting tun, and undoubtedly contributes to in- crease the production of alcohol. During the winter and temperate months, when the distilleries are most actively at work, the temperature at which the worts are set is usually about 70° F. When much farinaceous deposite is present, the heat may be only 65°, because, in this case, a slow fermentation seems to favor the conversion of that starch into sugar. In some German distilleries a little chalk is mixed with the worts, to check acidity. 3. The fermentation. The yeast added to the worts as a ferment, ought to be the best top barm of the London porter breweries. About 1 gallon of it is requisite for every 2 bushels of meal and malt worked up in the mashing process ; and of this quantity only a certain propor- tion is introduced at the beginning; the remainder being added by degrees, on the second and third days. Should the fermentation flag, a little more may be added on the fourth or fifth day, and the contents of the tun may be roused by an agitator. About 8 or 9 gallons may be introduced four days in succession to the quantity of worts extracted from 60 bushels of the farinaceous materials ; or the third day's dose may be intermitted, and joined to the fourth on the subsequent day. 588 DISTILLATION. DISTILLATION. 589 Great diversity and no little caprice prevail amons distillers in respect of the periods of administering the yeast ; but they should be governed very much by the appearance of the fermentation. This process continues from nine to twelve or even fourteen days, accordin*' to circumstances ; the tuns being left quite open during the first five days, but being covered moderately close afterwards to favour the full impregnation of the liquor with carbonic acid, as a fermenting agent. In consequence of the great attenuation of the wort by the generation of so much alcohol, no good body of yeast continues to float on the surface, and what is formed is beat down into the liquor on purpose to promote the fermentation. The temperature of the wash gradually increases till towards the end of the fourth day, when it attains its maximum height of about 25° above the pilch of 65° or 60° at which it may have been set. The time of the greatest elevation of tem- perature, as well as its amount, depends conjointly upon the quality of the yeast, the nature of the saccharo-slarchy matter, and the state of the weather. It is highly pro- bable that the electrical condition of the atmosphere exercises a considerable influence upon fermentation. We know the power of a thunder-storm to sour vinous fluids. An experimental inquirv into the relation between electricity and fermentation, could not fail to prove both curious and profitable. , ,. •„ u The dimunition of the density of the wort is carefully watched by the distiller, as the true criterion of the success of his process. This attenuation^ as he calls it, is owing partly to the decomposition of the sugar, which communicated its gravity to the solution, and partly to the introduction of the lighter alcoholic particles. Were a." the saccharo- starchy matter resolved into gaseous compounds, the wort would become water ; out since a part of it remains undecomposed, and a portion of alcohol is produced at the expense of the decomposed part, the degree of attenuation becomes a somewhat complicated pro- blem in a theoretical point of view ; the density due to the residuary sugar being masked and counteracted by the spirit evolved. Could the alcohol be drawn off" as it is formed, the attenuation would probably become greater, because the alcohol checks the fermenta- tive action, and eventually stops it, before all the saccharum is decomposed. After the wash has taken its highest degree of temperature, not much more spirit is found to be generated ; were this therefore removed by proper means, the remaining vegetable mat- ter would undoubtedly yield a further product of alcohol. , «/.« v ♦ In the attenuation of raw-grain wash, the specific gravity seldom arrives at 1-000 ; but most commonlv stops short at 1-002 or 1-004. When the vinous fermentation comes to an end, the acetous is apt to commence, and to convert a portion of the alcohol into vin- egar - a result which is easily ascertained by the increasing specific gravity, sour smell, and acidulous reaction of the wash upon litmus paper, which remains after the paper is heated, showing that the red color is not caused by carbonic acid. r u -i- Fermentation proceeds with more uniformity and success in the large tuns of the dis- tiller, than in the experimental apparatus of the chemist; because the body of heat generated in the former case maintains the action. Bui I have succeeded in obviating this inconvenience in operating upon 80 or 90 gallons, by keeping up the temperature, when it begins to flag, by transmitting hot water through a recurved pipe plunged into the tun. - . . . . r • We have already mentioned that one gallon of spirits, one in ten over-proof, is upon the average generated from 11-04 lbs. of starch sugar; hence we conclude that one pound water-measure of spirits at proof (= .^- imperial gallon) is produced from one pound of the saccharum. , . Malt whiskey.— The treatment and produce of malt distilleries are in some respects diflferent from those of raw grain. Having been professionally emp oyed by the proprietors of both, I am prepared to state the peculiarities of the latter, by an example. 500 bushels of ground malt are first mashed with 9000 gallons of waler, heated to the temperature of 160° F. : 6000 gallons of worts are drawn off mlo the coolers, and let down into the fermenting tun at 68°. From 3 to 4 per cent, of a mixture of London porter yeast with quick Scotch barm are added, and well stirred through the mass. At the end of two or three days, in general, the fermentation is finished. On the residuary grains of the malt, from 4500 to 5000 gallons of waler at 180° are run, which after proper mashing as before, are drawn oflf; then 4500 more are poured on, the drainage of which is added to the second. Both of these together, con- Btituting 9000 gallons, are heated next day, and employed for the mashing of 500 bushels of fresh malt. During the fermentation, the wash which was set at the spec. grav. 1-065, comes down to water = 1-000. The wash is distilled in two stills, appropriated to it, of about 800 gallons capacity each provided with a rotatory chain apparatus for preventing the lees from adhering to the bottom of the still. Into about 800 gallons of wash 8 lbs. of soap are put. The Hquor obtained at this first distillation is called low wines. These low wines are redis* tiUcd in the spirit stills; the first and last portions of liquid being "'«f«^^'*;*'f^,^'"^_^' ■li^ky in color^ and rank in flavor, are run into a separate receiver called the faints-back i While the middle portion, constituting in a well-managed distillery, from three fourths to four fifths of the whole, are received into the spirit-back. The faints are mixed with a largf quantity of water, and redistilled, in order to free them from the fetid oil derived from the husks of the grain. The interception of this noxious oil may be best eftected by a self-regulating bath, between the capital of the still and the refrigeratory, as will be explained in treating of Stills. The capitals of the common Scotch stills are made from 15 to 20 feet high, in order to prevent the chance of the wash boiling over into the worm ; and they are, towards the beginning of the process, struck from time to time with a rod, and by the sound emitted it is known whether they be empty, partially filled, or in danger of an overflow; in which case the fire is damped, by a spout near the furnace door, connected by a leather pipe with an elevated reservoir of wat"/. When very pure spirits are wished for, a third or even a fourth distillation is had recourse to ; there being a quantity of water mixed each time with the spirit in the still, to pre- vent its acquiring a harsh alcoholic flavor. According to some experienced distillers from raw grain, the mashing temperature of the first liquor should not exceed 140° F. ; whereas with malt 't may be safely and beneficially 165° or 170°. When rye is used instead of malt, 90 bushels of it are mixed with 190 bushels of raw grain, constituting 280 bushels in whole, for the mashing of which 5200 gallons of water are required. An hour and a half more time is necessary for settling the mashing of the above mixture, than of grain alone. Gin is made in this way. The distiller of malt whiskey calculates on obtaining two gallons of proof spirits from one bushel of malt, in average years. The highest yield is 20 gallons per quarter of 8 bushels ; and the lowest is 16, when the malt and fermentation are indifferent. The best temperature to set the fermenting tun with malt wash is about 70° or 72° F. When malt is 5s. the bushel, 6 bushels at 30*. will yield 12 gallons of proof spirits. These cost therefore 2s. 6d. per gallon for the malt ; to which must be added 3d, per bushel for the amount of malt duty not returned, or l§(f. on the gallon ; this added to the Scotch duty of 3s. Ad. the gallon, makes the price altogether 5s. ll^d.; besides the ex- penses in fuel, yeast, labor, and rent, which may be estimated at 8^d. per gallon. But3(i. may be deducted for what is paid by the dairymen for the spent wash and grains. The total cost, therefore, exclusive of use of capital, is 6s. 5d. per gallon in Scotland. The following is the work of a Scotch distillery, where good malt whiskey wa« made. One bushel of the malt weighed 35 lbs., or the boll, = 6 bushels, 210 lbs. In mashing each boll of malt, 110 gallons of water were run on it at 160° F. As soon as the fer- menting tun of 3000 gallons capacity was charged with the wash at from 64° to 74° F., 2 gallons per cent, of barm were added. When the wash had become attenuated from 1-060 to 1-040, another gallon of barm was introduced. The temperature of the fermenting wash sometimes rises to 96°, which is, however, an extreme case, and not desirable. When the bubbles of carbonic acid mount in rapid succession, it is reckoned an excellent sign. If the tun be small, and stand in a cool apartment, it should be started at a higher temperature than in the reverse predicament. Should the fermentation be suffered to flag, it is in £,eneral a hopeless task to /estore vigorous action. Some try the addition of bubs, that is, of some wort brought into a state of rapid fermentation in a tub, by a large proportion of yeast, but seldom with much success. Indeed, the law prohibits the addition of any wort to the tun at a later period than 24 hours after it is set ; so that if bubs are used afterwards, the distiller is apt to incur a penalty. The maximum quantity of proof spirits obtained on the great scale at any time from raw grain mixed with from one fourth to one eighth of malt, seems to be 22 gallons per quarter. By the British laws a distille-^'S not allowed to brew and distil at the same time j but he must work alternately, one week, for instance, at fermentation, and next week at distillation. In fermenting solutions of sugar mixed with good yeast, the attenuation has been carried down to 0*984, and even 0*982, that is, in the language of the excise, 16 and 18 de- grees below water, from 1*060, the density at which it was originally set in the tun. This was excellent work done on the scale of a great distillery nearly 30 years ago, when dis- tillation from sugar was encouraged, in consequence of bad corn harvests. In an experiment which I made in 1831, for the information of a committee of the House of Commons, on the use of molasses in the breweries and distilleries, I dissolved 1 cwt. of raw sugar in water, so as to form 74^ gallons, inclusive of 2 gallons of yeast. The specific gravity of the mixture was 1-0593 on the 31st of March. By the 6th of April, that is, in 6 days, the gravity had sunk to 0-992, or 8 degrees under water, which was reckoned a good attenuation, considering the circumstances and the small quantity operated upon. By distillation it afforded at the rate of 14*875 gallons of proof spiritt for 100 gallons of the wash. />90 DISTILLATION. DISTILLATION. 591 li When the distillers first worked from sugar, they only obtained upon an average from 1 cwt. 10-09 gallons imp. of proof spirit; but they afterwards got no less than 11-92 imp. gallons. The following experiment, which I made upon the fermentation of West India molasset into spirits, for^'the information of the said committee, may prove not uninteresting to my readers. 150 lbs. were dissolved in water and mixed with 2 gallons of yeast, weighing exactly 20 lbs. The wash measured 70 gallons, and had a spec, gravity of 1-0647 at 60^ F. In two days the gravity had fallen to 1-0055; in three days to 1*0022 ; and in five days to 1-001. The temperature was Kept up at from 80" to 90" F., during the last two days, by means of a steam pipe, to favor the fermentation. The product of spirits was 11 gallons, and ^^A of a gallon. Now 150 lbs. of the above molasses were found to contain of solid matter, chiefly uncrystallizable, 112 lbs. And as 112 lbs. of sugar are estimated by the revenue laws to afford by fermentation 11^ gallons imp. of proof spirit, the result of that experiment upon molasses must be considered satisfactory, bearing in mind that the saccharine S"Hstance in molasses has been not only partially decomposed by heat, but is mixed with some of the glutinous or extractive mattei of the cane. Since the alteration of the excise laws relative to distillation in 1825 and 1826, when permission was given to set the wort at lower gravities, the quantity of spirits produced from 1 quarter of corn has been much increased, even up to fully 20 gallons ; and the proportion of malt has been much diminished. The latter was soon reduced from three sevenths malt, and four sevenths barley, or two fifths malt and three fifths barley, to one fifth of malt and now to one tenth or even one sixteenth. A discussion having lately taken place in Ireland between certain persons connected with the distilleries and the officers of the excise, whether, and to what extent, raw grain worts would pass spontaneously into the vinous fermentation, the Board in London requested me to superintend a series of researches in a laboratory fitted up at their office, to settle this important point. I shall content myself here with giving the result of one experiment, out of several, which seems to me quite decisive. Three bushels of mixed grains were taken, consisting of two of barley, one half of oats, and one half of malt, which, being coarsely ground by a hand-mill, were mashed in a new tun with 24 gallons of water at 155". The mash liquor drawn off amounted to 18 gallons, at the density of 1-0465 ; and temperature of 82° F. Being set in a new tun, it began to ferment in the course of 12 hours, and in 4 days it was attenuated down to gravity 1-012. This yielded, apon distillation in low wines, 322 gallons, and by rectification, in spirits, 3*05 ; while the quantity equivalent to the attenuation by the tables was 3-31, being an excellent accordance in such circumstances. The inquisitorial regime imposed by law upon our distilleries, might lead a stranger to imagine that our legislators were desirous of repressing by every species of annoyance the fabrication of the fiery liquid which infuriates and demoralizes the lower population of these islands. But alas! credit can be given them for no such moral or philanthropic motive. The necessity of the exchequer to raise a great revenue, created by the wasteful expenditure of the state, on the one hand, and the efforts of fraudulent ingen-iity on the other, to evade the payment of the high duties imposed, are the true origin of that regime. Examinations in distilleries are constantly making by the officers of excise. There is a survey at 6 o'clock in the morning, when the officers take their accounts and gauges, and make calculations which occupy several hours. At 10 o'clock they again survey, going over the whole premises, where they continue a considerable time, frequently till the succeeding officer comes on duly; at 2 in the afternoon another survey takes place, but not by the same people ; at 6 in the evening the survey is repeated ; at 10 there comes another survey by an officer who had not been engaged in any of the previous surveys of that day. He is not relieved till 6 o'clock next morning. In addition to these regular inspections, the distilleries are subject to frequent and uncertain visits of the surveyor and general surveyor. " We are never," says Mr. Smith, the eminent distiller of Whitechapel, " out of their hands."* Before the fermented wort goes into the still, a calculation is made of the quantity of wash drawn from the wash back, and which is first pumped into what is called the wash charger. If the quantity in the wash charger . exceeds the quantity in the wash back, the distiller is charged upon the higher quantity ; if it contains less, he must pay according to the wash back, as being the larger quantity. When the quantity of wash is all transferred to the charger, the discharge cock of the wash charger is unlocked, and the wash is allowed to be drawn off from the charger into the still, the charging and discharging cock of the still being locked by the officer. There can be no transfer of wash but through the pumps, which are locked also. The first distillation from the wash is worked into the low-wine receiver, which is also a locked up vessel ; then of * Report of Committee on Molasses, 2198. those low wiaes, the strength and quantity are ascertained by the excise. The account of them afl^ards a comparison with the quantity which the contents of the wash-fc«, tliere is a pinion which takes into the teeth of the large wheel and upon tlie axle of this large wheel there is a pinion that actuates the intermediate wheel which turns another toothed wheel This last-mentioned toothed wheel takes into cogs upon the side railway, and hence, as the train of wheels moves round, the carriage to which the wheels are attached is slowly impelled forward. As soon a3 the wheels begin to move, and the carriage to advance, the wet cloth begins to uncoil, and to pass down over the first roller; a small roller attached to the carnage, as it passes over the rails in succession, holds the cloth against each rail for a short space of tinie, and prevente it from slipping, by which means the cloth descends in folds or loops between the rails, and is thereby made to hang in a series of folds or loops, as shown m the figure. It will be perceived that as the pivots of the cloth roller/ bear upon inclined planes, the roller will continually slide down as the cloth diminishes in bulk, keeping in con- tact with the drum, and delivering the cloth from the roller on to the several rails, as described. ^ In order to stop the carriage in any part of its course, or to adjust any of the folds of the cloth, a man is usually placed upon the platform travelling with the carriage, over which he has perfect command. This apparatus may be also employed for takmg the cloth when dried off the rails; in which case the carriage must be made to travel backward, and by first gmding the end of the cloth on to the roller/ and then putting the wheels in a retrograde motion, the cloth will be progressively coiled upon the roU^ /, in a similar way to that by which it was uncoiled. DRYING MACHINE (CENTRIFUGAL). {Hydro-extracteur ; Machh^ d. essorer, Fr.)— By this contnvance, Peutzoldt was enabled to deprive all kinds of wet clothes in a few minutes of their moisture, without compression or heat Kelly, a dyer. »nd Alliott, a bleecher, have since obtained a patent for the above machine with improvementa i^^^. 468 represents a partial section of the machine, a, a, is the frame; b, the vertical shaft turning in the step a, fixed on the bridge b. This shaft bears on ite upper part a friction cone c, from which it receives its movement of roUtion --^ % 598 DRYING MACHINE. DUNGING. 599 i; ') '•I as will be shown presently; c is a drum containing two concentric compartments d e^ of the form represented in the figure ; this drnm moves freely upon the shaft b, and 468. rests when it is not in motion upon two conical projections /, g, which form a part of the shaft. These two compartments are each composed mainly of metal, and their sides consist of tinned iron wire coiled circularly at very small distances from each other, and soldered together crosswise by small slips of metal. The top, which covers the inner compartment d, is secured by bolts and screws to a circle of iron which retains the wire sides of the same metal, but that which serves as a cover to the little compartment e, in which alone the goods are placed, is disposed so that it may be removed with ease, when these are to be introduced or withdrawn. It is furnished with an outer and inner border, disposed so that when the top is fixed the inner border presses upon the convex circumference of the central compartment, while the exterior border falls oatside of the edges of the other compartment. "While the machine is at work, the second plate is maintained in its place by pins or bolts, not shown in the figure. The sides of the outer compartment d, are connected with the bottom by means of • prolongation of cross bauds of metal which unite the wires and are riveted or soldered to the two outer plates. The wires of the interior compartment are attached by an iron hoop, to which they are riveted and soldered, and are united to the bottom plate by means of a rim upon this plate ; a rim somewhat flattened upon the sides which are nveted and soldered. D, is a regulator suspended in the inner compartment d, and whose two branches A, A, are loaded. These two branches having room to play around the bolts which serve as points of attachment, and which are fixed to the upper plate, terminate in kneed bran- ches whose extremities rest upon a rope ff, which projects from the shaft, i:, is an ex- terior envelope secured to the frame a, a. It encloses the whole drum except at top, and serves to catch the water thrown out of the goods. At y there is a stopcock for the dischai^e of this water, and the bottom contains besides the end of a pipe by which hot air is introduced. The vertical shaft b receives a movement of rotation and carries with it the drum. The more rapid this movement is the more does the centrifugal force tend to expel the water contained in the clothes or yarn to be dried. But as this force might also displace the central shaft, if the weight was not rightly distributed in the drum, and cause the dislocation of the machine when the great velocity requisite for quick drying is given to it, the regulator d is tested to prevent accident. The branches of this regulator spread wider the more the velocity is increased, and raise conse- quently the drum c above the conical enlargements, which permits the drum to be somewhat misplaced and to rectify its position conformably to the inequalities of its load, so that its centre of gravity may always coincide with its centre of rotation. The drum is connected with the shaft as is shown in z, leaving it free to take the requisite adjustment. To hinder it from rising too suddenly, a spiral spring k is fixed over the shaft immediately above the conical enlargement or. In order to maintain the equi- librium more certainly, the apparatus is surrounded with a hollow crown f, half filled with water, and if during the revolution of the machine the weight of the goods predominates on one side, that of the water which accumulates on the other side serves the more to counterbalance it The effect of this crown may be increased by dividing it into two compartments or more, o, is a lai^e pipe by which steam or hot air is intro- duced into the belly of the drum, which is pierced in this place with a great number of small holes to receive it The rotary movement is transmitted to the drum in the following way. I is a conical disc mounted upon the extremity of a shaft which actuates the cone o and the shaft b by means of friction ; l is a cone fixed upon the extremity of the shaft K L "is another cone of the same dimension, but whose base fronts the top of the other and which is placed on the shaft k" commanded by the prime mover, m is the belt which embraces the two cones, and whose lateral displacement^ effected by means of a fork, permits the velocity of the machine to be regulated at pleasure, n is the pulley which directly receives the movement In place of a single friction disc i, another may be employed, if judged necessary, and placed between the two, an additional friction pole in order better to equalize the friction. In this case the disc and additional cone should turn freely upon their own shafts. We may also adopt another arrangement for the bottom of the vertical shaft The shaft immediately above the step is surrounded br a loose rim, around which a certain quantity of lead shot, or other granular matter, is contained in the rim in the box which serves for the step. The top of this box is pierced with an opening, into which, when the machine is at rest a cord connected with the shaft sinks, controlled by the shaft ai the results of practice, have led him to conclude that there are only three primitive colors ; the red, yellow, and blue. If he attempts to make a white, by applying red, yellow, and blue dyes in certain quantities to a white stuff, in imitation of the philosopher's ex- periment on the synthesis of the sunbeam, far from succeeding, he wUl deviate still further from his purpose, since the stuff will by these dyes become so dark colored as to appear black The fact must not, however, lead us to suppose that in every case where red, yellow, and blue are applied to white cloth, black is produced. In reality, when a little ultra- marine cobalt blue, Prussian blue, or indigo, is applied to goods with the vrow of giving them the best possible white, if only a certain proportion be used, the goods wiU appear whiter after this addition than before it. What happens in this case ? The violet blue * Author, in Penny Cyclopedia. 7 1 604 DYEING. DYEING. 605 i fomw, with the brown yellow of the goods, a mixture tending to white or less colnr«i than the yellow of the goods and the blue together were. For thrsameTeaco^ Tm^ !h! M^Tlf^ ''l*"'',?" r-^'"'^"*^^ *° * P"'« *>^"«' ''«' «" examining closely the co of i the s.lk to be neutralized It was found by the relations of the complementary colo^, thM the violet was more suitable than the indigo blue formerly used. The dyer shouOnow that when he applies several different coloring matters to stuffs, as yeUow and blue foi example If they appear green, it is because the eye cannot distinguish the t^nts wh ch reflect the yellow from those which reflect the blue; and that, consequentHt 17^ TxWn ' ^f .^"^^^^'^ ^« r' P^'^'^^"' '^^' ^ "^'^'"••^ «^ combination appears ^Whe„wJ examine certam gray substances, such as hairs, feathers, &c., with the microscone w« see that the gray color results from black points disseminated over a coLTiror suthly :Slltret;!ke dy"e "'"'"" to compound colors, this instrument might be^u^s^^wlJj colI^L^ '^Wh'''''?i'* ^ acquainted also with the law of the simultaneous contrast of colors. When the eye views two colors close alongside of each other, it sees them differing mos m their optical composition, and in the height of their Tne' when the iw^ ^iSonThln'r'' "' 'r"-'"''''- r \^'' ^PP^" '"^^^ ^^^'^'^^ ^^ toTheir optVal^^^^ • ThuTnJ.V. '^^^P'^^^"^.? °f/he one of them is added to the color of the other.- green ben^fdZ f^ .t *'^°^'*^^ ^^.^ r"^« -<>"«; the red color complementary of green, being added to the orange, wiU make it appear redder; and in like manner the tensely blue. In order to appreciate these differences, let us take two green strides and two orange stnpes, placing one of the green stripes near one of the oran 'e Len nla^ ^e two others so that the green stripe may be at a distance from the o^ her i^reen strio? ^^side ''"'' "'^"' *"^ '**' "'*""" ^' ^ '^^^^""^^ ^^^"^ '^^ other on;nge,'aL on uS to^^ Nn^? TnTf}'' t"^ ^'T^J ""^ ?^'^"^' ^^ ""^y ^^''^r ourselves by taking the oy placing iVo 2 and No. 15 close alongside, putting No. 1 at a distance from No 2 Zar l^rjtl' '"' ^°- 'Y\ "" '''1''''' ^'-^"^ ^'- '' «" ^he same i^e'we sM see (If the pallet is sufficiently lowered in tone) No. 2 equal to No. 1 and No IS equal to^o. 16; whence it follows that No. 2, by the vicinity of No 15 wUl an^elx to have lost some of its color; while No. 15 will appear to havj acquired coW Wto black or gray figures are printed upon colored grounds, these figures are of the color crotTa.'? "' ^''-^"""r'- ^«-^''-»^^y» - «^der to judge of thdr dor, we mis bn tT * r-r^ ^^ ^.'l^ ^' ^^'^^ P^P^""' ^« *« ^« ^"«^ the eye to see nothing Irl 5 r^'V' ^""^ f ^^ "^''^ '« ^^^"^P*''^ fi?"'^^ «^ the same color, applied uiSn The relations of dyeing with the principles of chemistry, constitute the theory of the art, properly speaking; this theory has for its basis, the knowledge-1. of the species of ^L7ac" s'^f^fh'T'"' '"""i"^? '^"^^^^i '•. '^ ^^« circumstances in ;hfchSese pkI^ «r ,k' , i, *" Phf."^'".^'^^ ^i^ich appear during their action; and 4. of the prop. iT.nVi:tztiZ^T^s:^'" ^" ^^^"^- '''''' '-'''''''''' "-^ '^ '^^- thi*hTi!f P^^r'*^'''" ""^ ^^^ '^"^' *° ^ '^y^'^' ^^e^he*- fi^'-es, yarn, or cloth ; under ^e^ heads of ligneous matter, cotton, hemp, flax; and of the animal matters, silk ami 2. The mutual action of these stuffs, and simple bodies. d, Ihe mutual action of these stuffs, and acids. 4. The mutual action of these stuffs, and salifiable bases, as alumina, &c. 5. J he mutual action of these stuffs, and salts. 6. The mutual action of these stuffs, and neutral compounds not saline. ft nPA?'\} T''''' °^.'^^'^ ^^"^'' *"^ °^ °^« o'- "ore definite compounds. «. Ut dyed stufls considered in reference to the fastness of their color, under the in. fluence of heat, light, water, oxygen, air, boilings with soap, and reagenU. ?A /^r ?,^'"-' considered in its connexions with chemistry, opt^w. ^^'"^' considered in its relations with caloric, mechanics, hydrauUcs, and 1. The preparation of stuffs. The operations to which stuffs are subjected before dyeing, are intended-1. to sepa. rae from them any foreign matters; 2. to render them mire apt to unite withX S^rr^fJ^K ""' "^^"^ K^n'^^r P''^P°^"^ '° «^ "P«» »»»«"> i» o^der to give them • Tni-rf K ' ""^ °»ore brilliant aspect, or to lessen their tendency to assume a soiled appearance by use, which while surfaces so readily do. The foreign matters are eithS naturally mlierent m the stufls, or added to them ia the spinning, weaving, or oth« ™.inipulation of manufacture. The ligneous fibres must be freed from the colored azo- l^xed varnish on their surface, from a yellow coloring matter in their substance, from some lime and iron, from chlorophylle or leaf-green, and from pectic acid ; all natural combinations. Some of these principles require to be oxygenized before alkaline leys can cleanse them, as I have stated in the article Bleaching, which may be consulted in reference to this subject. See also Silk and Wool. A weak bath of soda has the prop- erty of preparing wool for taking on a uniform dye, but it must be well rmsed and aired before bein? put into the dye-vat. 2. Mutual action of stuffs and simple bodies. . Stuffs chemically considered being composed of three or four elements, already m a state of reciprocal saturation, have but a feeble attraction for simple substances. We know in fact, that the latter combine only with each other, or with binary compounds, and that in the greater number of cases where they exert an action upon more complete compounds, it is by disturbing the arrangement of their elements, and not by a resulting affinity with the whole together. 3, 4. Although stuffs may in a general point of view be considered as neutral in relation to coloring reagents, yet experience shows that they are more disposed to com- bine with acid than with alkaline compounds ; and that consequently their nature seems to be more alkaline than acid. By steeping dry wool or other stuff in a clean state in an alkaline or acid solution of known strength, and by testing the liquor after the stuff is taken out, we shall ascertain whether there be any real affinity between them, by the solution being rendered more dilute in consequence of the abstraction of alkaline or acid particles from it. Wool and silk thus immersed, abstract a portion of both sulphuric and teuriatic acids; but cotton and flax imbibe the water, with the rejection of a portion of the acid. The acid may be again taken from the stuffs by washing them with a sufficient quantity of water. ... 6. The affinity between saline bodies and stuffs may be ascertained in the same way as that of acids, by plunging the dry stuffs into solutions of the salts, and determining the density of the solution before the immersion, and after withdrawing the stuffs. Wool abstracts alum from its solution, but it gives it all out again to boiling water. The sulphates of protoxyde of iron, of copper, and zinc, resemble alum in this respect. When silk is steeped for some time in solution of protosulphate of iron, it abstracts the oxyde, gets thereby dyed, and leaves the solution acidulous. Wool put in contact with cream of tartar decomposes a portion of it; it absorbs the acid into its pores, and leaves a neutral salt in the liquor. The study of the action of salts upon stuffs is at the pres- ent day the foundation of the theory of dyeing ; and some of them are employed imme- diately as dye-drugs. 6. Mutual action of stuffs, and neutral compounds not saline. Several sulphurets, such as those of arsenic, lead, copper, antimony, tin, are suscepti- ble of being applied to stuffs, and of dyeing them in a more or less fast manner. Indigo, hematine, breziline, carmine, and the peculiar coloring principles of many dyes belong to this division. 7. Mutual action of goods with one or more definite compounds, and dye stuffs. I shall consider here in a theoretical point of view, the most general results which a certain number of organic coloring matters present, when applied upon stuffs by the dyer. Indigo. This dye-drug, when tolerably good, contains half its weight of indigotine. The cold vat is prepared commonly with water, copperas, indigo, lime, or sometimes car- bonate of soda, and is used almost exclusively for cotton and linen ; immersion in acidu- lated watei Is occasionally had recourse to for removing a little oxyde of iron which attaches itself to the cloth dyed in this vat. The indigo vat for wool and silk is mounted exclusively with indigo, good potashes of commerce, madder, and bran. In this vat, the immediate principles with base of carbon and hydrogen, such as the extracts of madder and bran, perform the disoxydizing func- tion of the'^copperas in the cold vat. The pastel vats require most skill and experience, in consequence of their complexity. The greatest difficulty occurs in keeping them in a good condition, because they vary progressively as the dyeing goes on, by the abstraction sf the indigotine, and the modification of the fermentable matter employed to disoxyge- nate the indigo. The alkaline matter also changes by the action of the air. By the suc- cessive additions of indigo, alkali, &c., this vat becomes very difficult to manage with profit and success. The great affair of the dye • 's the proper addition of lime ; too much or too little being equally injurious. , r/. .u i w« Sulphate of indigo or Saxon blue is usea also to dye silk and wool. If the wools t>e ill sorted it will show their differences by the inequalities of the dye. Wool dyed m this bath put 'into water saturated with sulphureied hydrogen, becomes soon colorless, owing to the disoxygenation of the indigo. The woollen cloth, when exposed to the air for some time resumes its blue color, but not so intensely as before. 606 DYEING. DYEING. 607 The properties of hematine explain the mode of using logwood. When stuffs are dyed in the infusion or decoction of this wood, under the influence of a base which acts upon the hematine in the manner of an alkali, a blue dye, bordering upon violet is obtained. Such is the process for dyeing cotton and wool a logwood blue by means of verdigris, crystallized acetate of copper, and acetate of alumina. When we dye a stuff yellow, red, or orange, we have always bright tints; with blue, we may have a very dark shade, but somewhat violet ; the proper black can be obtained only by using the three colors, blue, red, and yellow, in proper proportions. Hence we can explain how the tints of yellow, red, orange, blue, green, and violet, may be browned, by applying to them one or two colors which along with themselves would produce black ; and also we may explain the nature of that variety of blacks and grays which seems to be indefinite. Nutgalls and sulphate of iron, so frequently employed for the black dye, give only a violet or bluish gray. The pyrolignite of iron, which contains a brown empyreumatic matter, gives to stuffs a brown tint, bordering upon greenish yellow in the pale hues, and to chestnut brown in the dark ones. By galling cotton and silk, and giving them a bath of pyrolignite of iron, we may, after some alterna- tions, dye them black. Galls, logwood, and a salt of iron, produce merely a very deep violet blue; but by boiling and exposure to air, the hematate of iron is changed, becom- ing red-brown, and favors the production of black. Galls and salts of copper dye stuflt an olive drab, logwood and salts of copper, a violet blue; hence their combination should produce a black. In using sumach as a substitute for galls, we should take into account the proportion of yellow matter it contains. When the best possible black is wanted upon wool, we must give the stuff a foundation of indigo, then pass it into a bath of log- wood, sumach, and proto-sulphate of iron. The sumach may be replaced by one third of its weight of nutgalls. 8. Of dyed stuffs considered in reference to the fastness of their colors, when exposed to water, light, heat, air, oxygen, boiling, and reagents. Pure water without air has no action upon any properly dyed stuff. Heat favors the action of certain oxygenized bodies upon the carbonaceous and hydro- genous constituents of the stuff; as is seen with regard to chromic acid, and peroxyde of manganese upon cotton goods. It promotes the solvent action of water, and it even affects some colors. Thus Prussian blue applied to silk, is reduced to peroxyde of iron by long boiling. Light without contact of air affects very few dyes. Oxygen, especially in the nascent state, is very powerful upon dyes. See Bleaching, The atmosphere in a somewhat moist state affects many dyes, at an elevated tcm perature. Silk dyed pink, with safflower, when heated to 400* F., becomes of a dirty white hue in the course of an hour. The violet of logwood upon alumed wool becomes of a dull brown at the same temperature in the same time. But both stand a heat of 300* F. Brazil red dye, turmeric, and weld yellow dyes, display the same phenomena. These facts show the great fixity of colors commonly deemed lender. The stuffs become affected to a certain degree, under the same circumstances as the dyes. The alterabiliiy even of indigo in the air is shown in the wearing of pale blue clothes ; in the dark blue cloth there is such a body of color, that it resists proportionally longer ; but the seams of coats exhibit the effect very distinctly. In silk window curtains, which have been long exposed to the air and light, the stuff is found to be decomposed, as well as the color. Boiling was formerly prescribed in France as a test of fast dyes. It consisted in putting a sample of the dyed goods in boiling water, holding in solution a determinate quantity of alum, tartar, soap, and vinegar, &c. Dufay improved that barbarous lest. He considered that fast-dyed cloth could be recognised by resisting an exposure of twelve hours to the sunshine of summer, and to the midnight dews; or of sixteen days in winter. In trying the stability of dyes, we may offer the following rules : — That every stuff should be exposed to the light and air ; if it be intended to be worn abroad, it should be exposed also to the wind and rain ; that carpets, moreover, should be subjected to friction and pulling, to prove their tenacity; and that cloths to be washed should be exposed to the action of hot water and soap. In examining a piece of dyed cotton goods, we may proceed as follows: — Suppose its color to be orange-brown. We find first that it imparls no color to boil- ing water; that protochloride of tin takes out its color; that plunged into a solution of ferroprussiate of potash it becomes blue ; and that a piece of it being burned, leaves a residuum of peroxyde of iron ; we may thence conclude that the dyeing matter is peroxyde of iron. Suppose we have a blue stuff which may have been dyed either with indigo or with Prussian blue, and we wish to know what it will become in use. We inquire first into the nature of the blue. Hot water slightly alkaline will be colored blue by it, if it has been dyed with sulphate of indigo ; it will not be colored if it was dyed in the indigo vat, but it will become yellow by nitric acid. Boiling water, without becoming colored itself, will destroy the Prussian blue dye ; an alkaline water will convert its color into an iron rust tint; nitric acid, which makes the indigo dye yellow, makes that of Prussian blue green. The liquor resulting from boiling alkaline water on the Prussian blue cloth, will convert sulphate of iron into Prussian blue. 9. Division. Of dyeing viewed in its relation to chemistry. The phenomena of dyeing have been ascribed to very different causes ; by some they were supposed to depend upon mechanical causes, and by others upon the forces from which chemical effects flow. Hellot, in conformity with the first mode of explanation, thought that the art of dyeing consisted essentially in opening the pores in order to admit coloring matters into them, and to fix them there by cooling, or by means of a mordant imagined to act like a cement. Dufay in 1737, Bergmann in 1776, Macquer in 1778, and Berthollet in 1790, had re- course to chemical affinities, to explain the fixation of the coloring principles upon stuffs, either without an intermedium, like indigc^ walnut peels, annotto; or by the interven- tion of an acid, a salifiable base, or a salt, which were called mordants. W^hen bodies present phenomena which we refer to an attraction uniting particles of the same nature, whether simple or compound, to form an aggregate, or to an aflinity which unites the particles of different natures to form them into a chemical compound, these bodies are in apparent contact. This happens precisely in all the cases of the mutual action of bodies in an operation of dyeing ; if their particles were not in apparent con- tact, there would be absolutely no change in their respective condition. When we see stuffs and metallic oxydes in apparent contact, form a mutual union of greater or less force, we cannot therefore help referring it to aflinity. We do not know how many dyes may be fixed upon the same piece of cloth ; but in the operations of the dye-house sufl5ciently complex compounds are formed, since they are always stuffs, composed of three or four elements, which are combined with at least binary acid or basic com- pounds; with simple salts compounded themselves of two immediate principles at least binary ; with double salts composed of two simple salts ; and finally with organic dye- stuffs containing three or four elements. We may add that different species belonging to one of these classes, and different species belonging to different classes, may nniie simultaneously with one stuff. The union of stuffs with coloring matters appears, in general, not to lake place in definite proportions; thouzh there are probably some exceptions. We may conclude this head by remarking, that, besides the stuff anl the coloring matter, it is not necessary, in dyeing, to distinguish a third body, under the name of mor' dant ; for the idea of mordant does not rest upon any definite fact; the body to which this name has been given being essentially only one of the immediate principles of the colored combination which we wish to fix upon the stuff. 10. Division. Of dyeing in its relation with caloric, mechanics, hydraulics, pneumatics, and optics. Dyeing baths, or coppers, are heated directlyby a furnace, or by means of steam con- ducted in a pipe from a boiler at a certain distance from the bath. In the first case, the vessels are almost always made of copper ; only, in special cases, for the scarlet and some delicate silk dyes, of lin ; in the second case, they are of copper, iron, or wood. A direct fire is more economical than heating steam pipes, where there is only one or two baths to heat, or where the labors are often suspended. Madder and indigo vats, when heated by steam, have it either admitted directly into the liquor, or made to circulate through pipes plunged into it, or between the copper and an exterior iron or wood case. See the end of this article. Everything else being equal, dyeing with heat presents fewer difliculties towards obtain- ing an evenly color, than dyeing in the cold ; the reason of which may be found in the following facts :— The air adhering to the surface of stuffs, and that interposed between the fibres of their constituent yarns, is more easily extricated in a hot bath than a cold one, and Ihus allows the dye liquor to penetrate more easily into their interior : in the second place, the currents which take place in a hot bath, and which tend incessantly to render its contents uniform, by renewing continually the strata of liquid in contact with the stuff, contribute mainly to render the dyeing evenly. In cold dyeins:, it is necessary to 3tir up the bath from time to time : and when goods are first put in, they must he care- fully dipped, then taken out, pressed, and wrung, several times in succession till they be uniformly moistened. The mechanical relations are to be found in the apparatus employed for wincing, sh-mg, and pressing the goods, as we have described under Calico Printing and Bandana. The hydraulic relations refer to the wash-wheels and other similar ap- paratus, of which an account is given under the same articles. The optical relations 39 608 DYEING. have been already considered. In the sequel of this article an antomatic dyeing vat wiJ be described. The extracts of solutions of native dye-stufis may be divided into two classes, in refer- ence to their habitudes with the oxygen of the atmosphere ; such as continue essentially unaltered in the air, and such as sufler oxydalion, and thereby precipitate a determinate coloring matter. The dyes contained in the watery infusions of the different vegetable and animal substances which do not belong to the second class, are feebly attached to their solvents, and quit them readily for any other bodies that possess an attraction foi them. On this principle, a decoction of cochineal, logwood, brazil wood, or a solution of sulphate of indiso, by digestion with powdered bone black, lose their color, in conse* quence of the coloring particles combining by a kind of capillary attraction with the porous carbon, without undergoing any change. The same thing happens when well- scoured wool is steeped in such colored liquids ; and the color which the wool assumes by its attraction for the dye, is, with regard to most of the above colored solutions, but feeble and fugitive, since the dye may be again abstracted by copious washing vrith simple water, whose attractive force therefore overcomes that of the wool. The aiu of a high temperature, indeed, is requisite for the abstraction of the color from the wool and the bone-black, probably by enlarging the size of the pores, and increasing the solvent power of the water. Those dye-baths, on the contrary, whose coloring matter is of the nature of extractive Cr apotheme, form a faster combination with stuffs. Thus the yellow, fawn, and brown dyes, which contain tannin and extractive, become oxygenated by contact of air, and in- soluble in water ; by which means they can impart a durable dye. When wool is impreg- nated with decoctions of thai kind, its pores get charged by capillarity, and when the liquid becomes oxygenated, they remam filled with a color now become insoluble in water. A similar change to insolubility ensues when the yellow liquor of the indigo vat getsoxydized in the pores of cotton and wool, into which it had been introduced in a fluid state. The same change occurs when protosulphate of iron is converted into persulphate, with the deposition of an insoluble peroxyde in the substance of the stuff. The change here effected by oxydation can, in other circumstances, be produced by acids which have the power of precipitating the dye-stuff in an insoluble state, as happens with decoction of fustic. Hence we perceive that the dyeing of fast colors rests upon the principle, that the colors dissolved in the vat, during their union with the stuff, should suffer such a change as to become insoluble in their former menstruum. The more this dye, as altered in its union with the stuff, can resist other menstrua or agents, the faster it will be. This is the essential difference between dyeing and painting ; or applying a coat of pigment de- void of any true affinity for the surface. If we mix a clear infusion of a dye with a small quantity of a solution of an earthy or metallic salt, both in water, the limpid liquids soon become turbid, and there grad- ually subsides sooner or later, according to the nature of the mixture, a colored precipitate, consisting of the altered dye united with a basic or subsalt. In this com- pound the coloring matter seems to actr the part of an acid, which is saturated by a small quantity of the basis, or in its acid relationship is feeble, so that it c in also combine with acids, being in reference to them a base. The decomposition of a salt, as alum, by dyes, is effected principally through the formation of an insoluble subsalt, with which the color combines, while a supersalt remains in the bath, and modifies, by its solvent refaction, the shade of the dyed stuff. Dyed stuffs may be considered as composed of the fibrous body intimately associated with the coloring matter, the oxyde, and acid, all three constituting a compound salt. Many persons have erroneously imagined, that dyed goods contained none of the acid employed in the dye bath ; but they forget that even potash added to alum does not throw down the pure earthy basis, but a subsalt ; and they should not ascribe to coloring matter a power of decomposition 8t all approaching to that of an alkali. Salts, containing stro»g acids, saturate a very large quantity of coloring matter, in proportion to their place in the scale of chemicid equivalents. Mere bases, such as pure alumina, and pure oxyde of tin, have no power of precipitating coloring matter ; when they seem to do so, they always contain some acid. Such salts, therefore, as have a tendency to pass readily into the basic state, are pecu- liarly adapted to act as mordants in dyeing, and to form colored lakes. Magnesia alfords as fine a white powder as alumina, and answers equally well to dilute lakes, but its soluble salts cannot be employed to form lakes, because they do not pass into the basic state. This illustration is calculated to throw much light upon dyeing processes in general. The color of the lake depends very much upon the nature of the acid, and the basis of the precipitating salt. If it be white, like alumina and oxyde of tin, the lake vill have, more or less, the color of the dye, but brightened by the reflection of white DYEING. 609 fight from the basis ; while the difference of the acid occasions a difference in the hue. The colored bases impart more or less of their color to the lakes, not merely in virtue of Uicir own tints, but of their chemical action upon the dye. Upon these principles a crinison precipitate is obtained from infusions of cochineal by alum and salt of tm, wh-ch becomes scarlet by the addition of tartar; by acetate of ead, a violet blue precipitate is obtained, which is durable in the air; by muriate of lime, a pmk brown precipitate falls which soon becomes black, and at last dirty green: by the solution of a ferruginous salt, the precipiutes are dark violet and black; and J^ like manner, all other salts with earthy or metallic bases, afford diversities of shade •rith cochineal. If this dye stuff be dissolved in weak water of ammonia, and be pre- Wn^f.'"''^ ^'T^ ""f ^'^1' ^ ^'"'^ ^?^'. '' °^^'"«^' ^hich, after some time! wfu become green on the surface by contact of air, but violet and blie beneath Hence it appears, that the shade of color of a lake depends upon theTgree of oxvdlfron or change of the color caused by the acid of the precipitating salt, u^=k thele^ee of ox?! dation or color of the oxyde which enters into union with the dye,\nd upon its quantU^ in reference to that of the coloring principle. J » «• " "P"" "s quanmy Such lakes are the difficultly soluble salts which constitute the dyein*' materials of stuffs. Their particles, however, for the purposes of dyeing, must exis^in a state of extremely fine division in the bath liquor, in order that they may pLe^rate alon- wfth it into the mmule pores of textile fibres, and fill the cavities obse^^ed by mean! of the microscope m the filaments of wool, silk, cotton, and flax. I have exainLTthese stiS-s with an achromatic microscope, and find that when they are properly dyed with fast ^ ors the interior of their tubular texture is filled, or lined at least, with coSg matJ^" )^rn . «l ^^^^ '*'"'^'''' ^^^ *^^^°""^ P^*"^^^^^^' s« finely 'I'vided that they caTpa^ i^„?L fl '"?" f '^7' " T ''P"l''. f ^y^^"^ ' ^"^ '^ the infusion mixed whh Us mo^ dant be flocculenl and ready to subside, it is unfit for the purpose. In the latter T^e the ingredients of the dye have already become aggregated intrcompoundst^coherlj and too gross for entering into combination with fibrous stuffs. Extractive matter and tonnin are particularly liable to a change of this kind, by the prolonged acUon of heaUa ^?h wh. ^'"'? "'fK'.K" "^""" ^.^^"^^^" °^ * ^^^«""& °^^"e^ affords ruseful dye baUi when m.xed with the solution of a salt having an earthy or metallic basis These circumstances, which are of frequent occurrence in the dye-house render it necessary always to have the laky matter in a somewhat soluble condition and to effect us precipitation within the pores of the stuffs, by previously imprTgna ng them with SJe salme solutions by the aid of heat, which facilitates their iniroductfon. " ^\iL^ """i: ?i u *PP^'^ ^° *"y ^^"^' ^^^ portion of it remaining upon the su-face of the fibres should be removed; since, by its combination with the color?n? matter h would be apt to form an external crust of mere pigment, which woSrblLkuDJhi Z2:^T'' '""'cTr^^ S^ ^'! ^'^^^ ^^^ ^»^«"«'-' «"d also exCst to no purple the dye ng power of the bath. For this reason the stuffs, after the applicat"onTf^e mordarit, are dramed, squeezed, washed, and sometimes (particularly witrcotton and Imen, m calico printing) even hard dried in a hot stove. The saline mordants, moreover, should not in general possess the crystallizine nronertr jn any considerable degree, as this opposes their affinity of composition for Uiecforh% J this account the deliquescent acetates of iron and alumina are more ready o aid the dyeing of cotton than copperas and alum. ^ ® Alum is the great mordant employed in wool dyeinff. It is freouentlv r?;cc/.i,r^ • water, holding tartar equal to one fourth the weight' of Ike alum in'S^^^^^ addition Its tendency to crystallize is diminished, and the resulting color Tbri/htTn^ The alum and tartar combine with the stuff without suffering any chan4 and^: decomposed only by the action of the coloring matters in the dve bath Th^ «in^ eTLt:^saltt'"''' ^H "'^'""^ -eia^. Sir Isaac Newton supposed colored matters to reflect the rays of lic^ht • some bodie. tL Id vol ^r'.K Vif °" -^ '^J'^u^ ""S ^^^''' '^o^o^- Mr. Delaval, however, proved, S ^ 2d vol. of the « Memoirs of the Philosophical and Literary Society of Manchester^ that, « in transparent colored substances, the coloring substince dL not reflet «n, 610 DYEING. DYEING. 611 ! 51 light ; anc that when, by intercepting the light which was transmitted, it is hindered from passing through substances, they do not vary from their former color to any otlier color but become entirely black ;" and he instances a considerable number of colored liquors, none of them endued with reflective powers, which, when seen by transmitted light, appeared severally in their true colors ; but all of them, when seen by incident light, appeared black ; which is also the case of black cherries, black currants, black berries, &c., the juices of which appeared red when spread on a white ground, or other- wise viewed by transmitted instead of incident light ; and he concludes, that bleached linen, &c., " when dyed or painted with vegetable colors, do not differ in their manner of actinff on the rays of light, from natural vegetable bodies ; both yielding their colors by transmitting through the transparent colored matter the light which is reflected from the white ground :" it being apparent, from difl'erent experiments, " that no reflecting power resides in any of their components, except in their white matter only," and that « transparent colored substances, placed in situations by which transmission of light through them is intercepted, exhibit no color, but become entirely black." The art of dyeing, therefore, (according to Mr. Delaval,) "consists principally in cover- ing white substances, from which light is strongly reflected, with transparent colored media, which, according to their several colors, transmit more or less copiously the rays reflected from the white," since " the transparent media themselves reflect no light; and it is evident that if they yielded their colors by reflecting, instead of transmitting the rays, the whiteness or color of the ground on which they are applied, would not in any- wise alter or aflfect the colors which they exhibit." But when any opaque basis is interposed, the reflection is doubtless made by it, rather than by the substance of the dyed wool, silk, &c., and more especially when such basis consists of the white earth of alum, or the white oxyde of tin ; which, by their strong reflective powers, greatly augment the lustre of colors. There are, moreover, some opaque coloring matters, particularly the acetous, and other solutions of iron, used to stain linen, cotton, &c., which must necessarily themselves reflect, instead of Uansmit- ting the light by which their colors are made perceptible. The compound or mixed colors, are such as result from the combination of two diflTcr- cntly colored dye stuffs, or from dyeing stufl's with one color, and then with another. The simple colors of the dyer are red, yellow, blue, and black, with which, when skil- fully blended, he can produce every variety of tint. Perhaps the dun or fawn col I-H t-H t-H l-H en f^ — H l-H r-t l-H t-H l-H I-H l-H l-H t-H _o 1 •c o 1—1 I-H o 00 o «N m O (N CO CO CO CO "* ■^ tJ< Tl< >o to O CO tH 1— t l-H l-H 1—1 l-H t— 1 t-H l-H l-H l-H l-H ^ H3 '3 • CO t-H l-H l-H l-H l-H l-H l-H l-H I-H l-H 1 "3 o to I-H (N CO TJi >o CO i:- oo OS o l-H no a .t- a» l-H CO to 00 o co to i^- OS o o O l-t 1-1 T-i I-H (N (N (M (N (N s O od 1— • 1—1 l-H l-H t-H l-H ^H l-H l-H t-H l-H l-H l-H l-H l-H 1—» I-H l-H I-H I-H l-H -3 o o l-H f-t (N CO ^ to CO t- (X) OS o t-l to i:» OS l-H CO «o CO o c^ ■* X- O 00 00 00 OS OS OS OS o o o o c< B O tn o 1-^ o t-H o l-H o 1-^ o l-H o l-H o l-H l-H l-H t-H 1—1 l-H l-H 1—1 I-H O i o t-H 1— 1 00 OS o < CO to ir- OS l-H "^ CO 00 o O «o t^ t- r- r^ 00 QO 00 o .4^ o O . o O o o o o O o o o o s a 73 r^ rH t-H t-l l-H 1—1 l-H l-H l-H f-H ifH 3 S s CO u* o l-H (M CO "* lb CO X:- 00 OS o < •^ CO t-H l-H • f-* ec 00 o (N '^ CO 00 r-^ CO V Cs< o ■^ ■^ Ttt »o O to »o to o CO fe o o CO O o ,-H O o l-H o l-H O r-H o l-H o l-H o l-H o o 2 s 1 '4J > *» ^ O t-l (N CO Tjt lO CO X- 00 OS o l-H 3 Cl, 4^ es TS . o (M ■* <£> OS l-H CO U3 X- OS l-H s 08 o O (M » (M (M CO CO CO CO CO Til O QQ O t-H O O 1—1 o l-H o l-t o l-H o l-H o I— 1 o l-H o l-H o 5 O O V B &i *S o f-t e o o «3 >> *» ^ o o t-H l-t *i o l-H < ^ <3> »^ ft O O 1-4 00 to t- OS f-l CO to t- OS l-H ja «o «o CO eO «o i- t- X' j:- Xr- 00 u QQ a» a» OS OS OS o» OS OS OS os OS M *4 o QO ft 02 o 00 »H 00 OS o l-H 6 d CO \o t- OS l-H CO to t- OS l-H "S •^ •»*< tJ* Tt« ""it to W3 to to to CO S) CD a» o» OS OS OS OS OS OS OS OS OS £ o e 956; deduct 956 from the sp. gr. of the bulk, or 1076, and 120 will remain; refer that to its amount on the head line of table No. 2, namely, 120, under which will be found S. representing 3 lbs. of sugar to the gallon ; and by running the eye down its column U> opposite the alcoholic strength indicated (35 »p) will be found 14-9, which represents the per centage of water displaced by the sugar, and which amount of 149, ajided to I the 35 per cent ascertained, makes the total upon the bulk 49*9 per cent »p, with 3 lbs. of sugar to the gallon. . , , /• jak^t.*i,,>« For Gins, ac.— Example 3. In taking the sp. gr., suppose it to be found 957 , then submit to the boiling point, and it proves to be 14 "p, whose sp. gr. is 937, which, deducted from 957, loaves sp. gr. 20; on the head-line of table No. 2, under 20, will be found J or i lb. of sugar to the gallon, and on running the eye down to opposite ><.^ «. - . -' . rt"i aatta«l^l J i nnr««t'1i' ir T iiii » i. aey 620 ELAINE. ELASTIC BANDS. 621 ii I li-T, will be found 80, which, added to the 14, makes the total on the bulk 17 per cent"P, with 50 lbs of sugar to the 100 gallons. To chemists for their tinctures, J_3:j 622 ELECTIVE AFFINITY. which advances as the screw turns, and carries w.•f^ If . ♦• ,.. i. . . the disc D, carried upon a shoulder con«f«nfi 1 * ^ *'f "* '^^'''^ ^" '^s turn pushes guided by two ears wlTich slide in two '^^v\"s/„t^^^^^^^^ /h^\^"'^"r P'« ^^ouFder is diameter of the pinion p is about one fifth of TJJX ^^'''^''^'^ «^ ^^ table. The A tnrns five times less quickly than the arbor A' «n^^^^ ^ *^*' ^^^ arbor butes further to slacken the movement of traLtaJion of rh' ^."'"''' ^^ ^^^ ^^''^^ ^ «>«tfi- When the disc is all cut down, the sho^wir Z f ^^ ^'^\ to their original position by lifting the nut wh^h l''v"^ 1^' ""'^ i? ^"*"^»^* »«** upon the shoulder by means of sharp noints «nH " ^'"^^^ **"• ^^^^ disc is fixed the washer have a /ery small dSerin orSer tTatirknT'"- • '''^ •^'^'U^" '^'^^^ disc, advance as near as possible to the centre ^^' "" ^^'^^'''S ^^'^ *^« The rotatory movement of the disc and itJ c»,«.,m • • w,^ which governs a pinion p' provid^ with in t '/k'' ^7'" ^^/" ^"^^^^^ ^'^'-^'^ ppoi which the shoulder is m';,Cd Thf arL x' nV^ v '^'"if ^^ '^^ '^^^ ^ Its motion from the first shaft a, by mears of thP^K i "i ^?^^^'' "^''^^ ^^<^«^^ shafts, and of an intermediate wheel s^ Th.i y'^^,^'^ s and s' mounted upon these the shaft A", is intended merely to allow this ' hT^'f ' ""^ ^ ^T'^^' ^"^^ ^« ^»»»« «<" di^eterof the wheel Of this iLt ^^i^^o^^^^^'^^::^^^^^^^ ^^P'i^^etZ^^^^^^^^ /i^- 476.-The riband is engaged washers keep these knives apart ^t a dttanc.wh'K^ "P°" '^' '^^^''' «' ^ 5 thin^rass washers mounted with screXon each rdCm Jn/''' T^ ^^ ^^"^^' «"d two extreme these rollers traverse two uprr^hts l i r„?^- "u^i'' ^^^ ^^«^« ^y^tem. The axes of screws to approximate them ar;retur::\^^^^ brasses, aad with adjusting P cosure. xne axis of the lower roller carries a wheel 476 », which takes into another smaller wHp*.! ♦^ »i..^ IT : — which is driven by a cord. The dirmefer^'/?K k"^? ^^^ J^™^ '^^" «« ^he pulley p. wheel r'. The pulley p s twice thrill o/ it" Ju'f l'' '^'a'' ''""^ ^''ealer thaMhe drum B, which drives the rest o? the machine ' ^"'^ '^' '°'^ P^^^^« «>'»»d a The threads, when brought to this Bfat« «r i j filled with cold' water; they are n ex softened nwT'/ ^'' ^i^' ««ccessively into tubs possible in the following manner -Thevar. w J h ^^"' ^"^, ^^°"=*^^^ ^^ much as the operative stretches^the caoutchouc thread wUrhisXSd' Tn iv'"'' ^."^^''^^' ^^"^ 8 or 10 times longer. The reels when thus filled «r.nw!^' ^ ■ *^" "^^ '^ ^^ rendered apartment, where the threads become firm « mil t^K^ ^"u"-^ '^'"^ ^^^^ ^n a cold This state of stiffness is esseS fhr /J' ^^^™ ]P '^^^""^ ^^^'^ "^ture. threads are commonly covered wUh a sheath nri."^ '^ subsequent operations. The chine, and are then placed as wTrn in a ?^^ '^ ^'^\' "''"'?' °' ^^"^°' ^^ « braiding ma- garters, &c. If the gum werlto el?.^": "" T^^" ^^ ?'°^ * "^'"'•^^ ^^^b for braces, ferent threads would beTenXVed anS .hn '^' J^^^^'^^'r. during this operation, the dlf! a puckered tissue. It is Jequisife therefor, to^'w '" ^VT^^l ?^""^^> «« ^^ ^o form extensible, or at least incon?rac le^nnH;/^ ^^^""r ^^^ ^^'^^^^ ^" ^heir rigid and in^ to the threads of caoutchouc herapp^^^^^^^^^ '^' %l'}' ^' ^«-en^o restore effected by passing a hot smoothinTirorover h. t'^* 'f ^^^? restoration is easily with blanket stuff. See Braiding MAcmNE '"""^^"^ "P^" * ^^^^« *^«^ered ferSlTo^p™^^^ Germ.) denotes the order of pre- really, the gradation of attractive for eYnftej rifmiltfw'^ '^'' *" *=""^^"^ ' «' Objects Of nature, Which determines ^^rfJ^l^^ZZ':^^^:^^^^^^^^ ELECTRIC TELEGRAPHS. 623 amidst indefinite variety of combination. The discussion of this interesting subject belongs to pure chemistry. See DEOOMPOsmoN. ELECTRO-TELEGRAPHY. Magnetic Needle Telegraphs.— ASiev CErsted had dis- covered the mutual action of electric currents and magnetic needles, Ampere " pro- posed, in consequence of an idea suggested to him by the illustrious Laplace, to employ as many circuits as there were letters of the alphabet, and to make each of them act on a separate needle." Schweiger's invention of the galvanometer, followed more recently by "Wheatstone's discovery of the velocity of electricity, gave renewed impulse to these inquiries. Professor Ritchie illustrated Ampere's idea on a small scale, but rather with a view of pointing out the difficulties which enveloped it than to propose it for practical pur- poses. Alexander's telegraph had thirty galvanometric needles and thirty-one wires ; each needle supported a screen, which it carried with it when deflected, and thus ex- posed a letter. Davy's first telegraph was of the same character, only the letters were illuminated. Baron Schelling and Fechner proposed to limit this number by employ- ing fewer needles and observing their combined motions, a different character being indicated according to the number of needles in motion. Mr. Bain has proposed to fix the magnet and deflect the coil. The arrangements peculiar to Mr. Wheatstone's needle telegraph are, that he has one wire only for each needle; that two needles are thus always included in the circuit; that the combination of the two needles out of five, which he generally used, will produce 20 signals, and that by a key-board, peculiarly his contrivance, these several circuits can be readily formed. By combining three or four needles, 200 signals can be given. As the motion of these deflected needles was not of itself sufficiently violent to ring a bell in order to call attention, arrangement was made that one of the needles by its deflection should complete the circuit of a distant battery, and this would then make an electromagnet, and liberate the detent of an alarm. Other modes of sounding an alarm were adopted on account of the difficulties which attended the early experiments on that form of telegraph which we shall presently describe. As it is not the intention to give here a history of telegraphs, the above illustrations of the chief applications of the galvan- ometer to this purpose will suffice. "The instruments to be first described are the inventions of Messrs. "W. Fothergill Gooke and Charles Wheatstone, F.RS. They arc of two kinds: the one, in which a n 62'! ELECTRIC TELEGRAPHS. ELECTRIC TELEGRAPHS. 625 1ft R't f single galvanometer is employed ; the other, in which there is a pair of galvanometera. The former will serve our present purpose, as the mechanical adjustments of the latter are merely the double of this. I have removed the case from the instrument in order to give a clear view of all the essential parts; and have engraved a back view of it {fig. 477) with the battery k attached as if for use; and the circuit of the galvanometer a completed by the wire w w. "The instrument is possessed of a two-fold character; it is passive, or ready for receiving signals from another instrument; it is active, or ready for transmitting signals to another instrument. By describing first how it is fitted for receiving signals, and then how it is arranged for transmitting them, we shall be better able conveniently to analyze it, and to comprehend its general structure. The frame of the coil b is of brass, or (which is in many respects better) of polished wood or of ivory ; it is screwed upon the face of the instrument, which face is a brass plate varnished on the inner side. Looking at the coil, a short wire from its right-hand end comes to a screw terminal, which latter, by a slip of brass neatly laid on the instrument case, is connected with another terminal u. The left-hand end of the coil comes also to a terminal, from which a slip of brass descends to a brass plate here, partly hidden ; but its form may be gathered from a similar plate, visible on the left side. These twin plates are in metallic connec- tion by means of the two upright springs, plainly shown in the drawing. The springs are of stout steel, and press strongly on two points in a short insulated brass rod n, which is screwed in the wooden framework of the instrument The left-hand plate is con- nected with the terminal d, also by a slip of brass. If now, the two terminals u and d are connected by a wire w w, the circuit will be complete, as follows: from the terminal u into the coil at the right-hand side; out of the coil, at the left-side downwards to the right-hand plate; up the right-hand steel spring, across the brass rod n to the left-hand steel spring; downward by this spring to the left-hand plate, thence by the slip of brass to the terminal d, and thence by the wire w w the terminal u, whence we started. If now the wire from u went up the line of railway, and the wire from d down the line, and the circuit were in some way kept complete on the large scale, as it has been here described on the small scale, any electric current passing along the wire from a distant station, would traverse this coil in its course, would deflect the needle, and so make a signal. I should here mention that for the sake of regularity, we adopt one unvaried order in attaching wires to the instrument; it is to put the up wire on the terminal, shown by u on the figure, the coils being all uniformly wound. "So far for receiving a signal — now for sending one. Were we to go out on the open railway, taking with us a battery, and to cut any one of the wires, and place its two ends, thus obtained, upon the two terminal ends of the battery, a current would pass along the line, and the needles on that wire would be deflected ; and if we changed bands so as to reverse the connections, the deflection* of the needle would be reversed. The same would happen were we to cut a wire inside the office, or inside the tele- graph, and to treat it in a similar way. Now, in every apparatus contrived for trans- mitting signals, we have a place corresponding to such a cut wire ; and near this place are the poles of the battery, mounted and moveable, so that they may be readily applied in the breach, one way or other as required. The place here {fig. 477) is the top of the springs. They are xiot joined to the brass rod n; but, as I said before, press hard upon it, and can readily be raised with the finger, or otherwise. It is obvious that, when either of them is raised, the circuit is broken. Now, near this place is a mechanical contrivance, by which the poles of the battery may make a breach in the circuit, and be applied in the breach in either direction. The drum b is of box- wood, the ends c and z being capped with brass, and insulated from each other by the wood, 6, left between them. The drum is moveable by a handle, not in sight here, and is supported as shown in the present figure. A stout steel wire c' is screwed beneath into the c end of the drum ; and a similar z' is screwed above into the z end. These two wires are the poles of the battery, z' being connected with the zinc end, and c' with the copper, thus: — from the copper end of the battery a wire is led to the terminal c; thence a slip of brass leads to a curved brass spring which presses closely on the drum at c ; from the zinc end of the battery a wire goes to the terminal 2, and thence a slip of brass leads to a similar curved spring, pressing on the continuation of the z end of the drum, as shown in the figure. It will be seen that, whenever the drum is moved, the steel wire z' will lift up one or other of the upright steel springs; it is now lifting up the right-hand one, and so breaks the circuit; but, by a little further motion of the drum, the wire c' will press upon the boss below, as shown in the figure, and thus there will be a battery pole on each side of the breach, and a signal will be made on this, and on all instruments connected with it And, from the peculiar arrangement with the drum, the motion can be changed as rapidly as the hand can move. I have shown the battery connections exactly as they occur in practice; and the connections are such that, if the right-hand springs are moved of^ the needle moves to tU> right, and, if the left, to the left The needle on the face of the instrument always hcis its north end upward, and the needle within the coil its north end downward, so i-hat if we look at the face of an instruments, and see the top end of the needle move to tiift right, we may be sure that in the half of the coil nearest to us the current is ascending."* Thus the wires are the channels through which electric influences are conveyed to great distances with inconceivable velocity, and the moveable magnets, or galvanometers, <:o which the wires are attached at the stations, are the parts of the apparatus by which signals are made. The mode of interpreting these signals is thus described by the author: — " Double-needle Code. — Having described the apparatus and means employed for producing at pleasure the transmission of signals to distant places, it now remains to us to explain the manner of interpreting these signals, so that each person shall under- stand the ideas the other would convey. "We have to describe how, out of only two needles, each of which has but two movements, the telegraph alphabet is formed. On the face of the instrument are the letters of the alphabet arranged, as it will be seen, seriatim in two lines, beginning at the left^ and ending at the rights as ii. writing. The commencing series from A to P is above the top end of the needles ; and the concluding series from R to Y below the bottom end. It will also be seen that some letters are engraved once, some ttoice, and others three times. To make a letter engraved once, requires one motion of the needle ; to make one engraved twice, tvoo motions of the needle ; and to make one engraved three times, three motions. In respect to the upper row, the needle nearest to the letter iu moved, and it is moved so as to point toward the letter. In respect to the lower row, both needles are moved, and their lower end is made to point in the direction of the letter required. Six of the letters C, D, L, M, and U, V, require a twofold motion of the needle or needles, first to the right then to the left for C, L, and U, and first to the left then to the right for D, M, and V. These six letters are engraved intermediate^ and with a double row between. The alphabet produced by this arrangement is of a simple character, and is very readily acquired. To the stranger it appears confused; but when he has the key to it the difficulty disappears; it might at first sight appear <^bat a dial instrument — a telegraph, that is, provided with alphabets engraved on a c'Veular dial, and an index made to revolve, and point to any required letter, is more simple; several such telegraphs exist; and among them are some very happily arranged ; and there is something so simple in the fact of being able to point to any desired letter, that it is no wonder the public generally may, on a hasty glance, and before studying the practical merits of the case, be ready to decide in their favor, and prefer them to any other plan, the A, B, C of which is less obvious. "But is it such a very serious matter to learn another alphabet? Every school- boy, now-a-days, knows some half-dozen alphabets; there are ROMAN letters lai^e, and Roman letters small; 3fAN US CRIF 2' Utters large, and manuscript letters small; #ltt JSnfllisf) large, and Old English small ; Greek large, and Greek small, and so on, and all different., and not one of them in which the letters are represented by so few strokes of the pen as are the telegraph letters by beats of the needle. Take one of our plainest alphabets as an example ; the ROMAN CAPITALS, for instance, and place a few of them in juxta-position witli the corresponding telegraph signals: — A \\ E / G /// B \\\ F // H \ "The simplicity of these symbols is obvious. Two diagonal and one horizontal line are required for the Roman A ; two diagonal lines for the telegraph A ; one vertical and three horizontal lines make the Roman E; one diagonal the telegraph E, and so on; the difference being that all the world have learned the Roman alphabet, and only a chosen few have studied the telegraphic symbols. That the latter really are simple and distinctive: that they are full of meaning and very legible; that they are applicable to ordinary language, and good, ay, very good! no one will for a moment doubt, who has seen the rapidity and accuracy with which a telegraph officer receives a dispatch. "To one who sees a telegraph in operation for the first time, the eficct borders on the marvellous ; setting out of the question the fact that the needles are caused to" move by an individual perhaps a hundred miles off; the motion of the needles hither and thither; quicker than the untrained eye can follow ; the want of all apparent order and rule in their movement; the ringing of the changes between one and the other, and both; the quiet manner in which the clerk points his needle to the letter E, in rapid intervals, implying that he understands the word; while, to the uninitiated looker-on, all is wonder and mystery, and confusion ; and the rare occurrence of the clerk pointing to »J«, implying he did not understand; and, finally, the quiet manner with which the clerk tells you, very coolly, as the result of his operations, "That the very pretty girl, with bright blue eyes and long curls, has sailed for Boulogne in th* Princess Clementine, now leaving Folkstone Harbor; and that she is accompanied by ,; 626 ELECTRIC TELEGRAPHS. F; the tall, handsome man, with the dark moustache and military eloak.' As he tells jon thip, and says, 'Message and answer, forty words two mien at 10ft 6dl, one guinea, porterage n shilling — one pound two.' If you happen to be the papa of the pair of blue eyos, you are bewildered, and wish you were an electric current, and could be sent after them." — From Electric Telegraph Manipulation, by C. V. Walker. An invention apparently very simple and comprehensive for electro-telegraphic correspondence, was made the subject of a patent in February, 1851, in Newton's Journal. It consists in the use of such parts or arrangement? of apparatus as will allow two or more persons, by the agency of electricity, to send or receive signals or intelligence by one common wire of communication or main conductor, whilst the rapidity or closeness in the order of succession of the signals, consequent on the in- definite short time the main conductor is in actual use in conveying the electric current for transferring the signal shall be such, that all the persons so employed in these telegraphic operations can be continually and simultaneously occupied, in like manner as if each one of them had a distinct wire of communication all the time waiting for or appropriated to his particular use. By this invention the same practical telegraphic results are obtained, through agency of the one wire or main conductor, as^ in the varieties of the electric telegraph before known or used, would require several distinct wires of communication. According to this improved plan of working, the wire of communication or electric conductor may be considered as a public word road, or an omnitelegraphic way; whereas, in contradistinction, the conductor, as heretofore used, may be considered a private word road, or a unitelegraphic way. In addition to the ability of allowing divers parties simultaneously to telegraph at will either all in the same or in contrary directions, over or along one wire of communication, this improvement enables each one of the operators, so employed, to have and to use as many distinct short wires or accessory conductors, all related to the main conductor, as the operators may desire to have separate signals; whereby the facility of making and receiving or recording signals or intelligence is greatly increased. Thus, for example, — suppose ten men at each end of the wire of communication are all using the same wire of communi- cation which connects the distant places, tlieir practical telegraphic facilities would be greater than could be had by the old system, if these twenty men had twenty different wires of communication in place of only one such wire; and would be as great as could be had by the old system, if each of those twenty men had as many such wires as they might desire to make or receive different signals. Thus, supposing twenty-five signals to be made and twenty-five to be received, for each of these twenty men, 1,000 separate wires or main conductors would be required, in order to accomplish what^ by the new system, requires only one such main conductor, aided by 1,000 short wires or accessory conduct- ors) or signal-making and signal-receiving wires, which need be of but a few inches in length severally, or so long as to reach to, or be systematically put into, electric relation with the respective ends of the main conductor or wire of communication ; or, otherwise by motion be successively brought into electric communicition with, and so momentarily forming in succession, portions of the conductor, by which the electric current, circuit, or line of inductive action is established, maintained, or broken, from time to time. It may be stated that this improvement rests upon taking advantage of the circumstance Itliat, practically speaking, no sensible portion of the time employed in working the telegraph is expended in the actual transmission of the electric influence, which is the medium or agent of the communication, but that is due to the operation of making or recording the signals. One wire, reaching between the distant places, is therefore capable of being the instrument of transmitting an indefinite number of different signals in a sec- ond of time, provided that suitable adaptations are made to enable so many different sig- nals to be separately placed upon one end of the main conductor, and received or recorded at the other end of the conductor, in an intelligible manner. There are an indefinite num- ber of methods of applying to practice this improvement^ differing more or less in kinds of apparatus used, and in modifications of electrical actions applied. But all are sub- stantially the same improvement; inasmuch as their action would be to set apart distinct and small and successive fractions of a second or other period, and assign and apply .such email fractions of time to different uses or for different persons; so that, although many persons should all simultaneously be employed in using one common wire of com- munication, yet all the signals so transmitted by it maybe successive; the rapidity of the electric conduction admitting, by this invention, the divers signals to be transmitted successively along the wire, and yet so quickly the one after the other, as to give a like practical result, as if they were simultaneously transmitted by separate wires or main conductors. A convenient mode of applying this improvement to practice, and for illustrating the principle of the invention, may be understood by referring to the diagram {fig. 478), wherein two pendulums, supposed to be actuated by clock work or other suitable means, are indicated; such pendulums being made to vibrate as nearly as possible together in position and in time of vibration. At the chief station a, the ELECTRIC TELEGRAPHS. 627 standard pendulum is situate; and the dependent telegraph station is also provided with a pendulum, as at b. d, d are the pendulum rods, with these balls or weights; E, the prolonged end of the pendulum rods, which should be much longer in proportion than represented in the drawing; f, slight springs, united to the prolonged end of the I p-rY>y-ynrrYVYYY^ YTYYTYYYrrr^^ pendulum rods; and p, b, p, andp, 9, p, are two grooves or pathways, so made that the spring F shall fall into the groove p, r, p, when the pendulum makes the vibration from left to right, and shall fall into the groove p, s, p, when making the vibration from right to left; c, c, is the main conductor or wire of communication, connecting the two tele- graphic stations a and b together ; x, x, are ground plates and ground wires. At station A, there are metallic points over which the spring f passes, touching the surface each vibration, — which points are connected with the conductors l, x. The groove p, r, p, at station b, is of metal, and in electric communication with l and x. The spring f, in moving in either of the grooves p, r, p, or in the p, s, p, of station a, is kept in its path by an insulated or non-conducting guide ; z is a Leyden jar, prime conductor of an electrical machine, or galvanic pile, kept constantly charged, or capable of giving a great number of visible sparks or electric pulsations per second, on making or breaking the electi'ic circuit or line of inductive action. The wire c, C3, c, has a metallic connection with the upper end of the pendulum rods, which arc also metallic as well as their prolonged ter- minations. In this condition of things, whenever the spring f, at station a, passes over K, K, in its vibrations, there will be an electric communication or circuit from z to k, through L, X, to the ground at station a; also from z to the metallic groove p, r, p, at station b, and to the ground there ; provided the pendulum at station b is making its vibration from left to right, when the pendulum at station a carries its spring f over the conducting point k. At k on the left-hand side of the standard pendulum, there are two metallic faces near together; by this arrangement it can be known at station b when the pendulum at station a is in motion, and the position of its vibrations exactly deter- mined; so that the pendulum at b can be from time to time set in motion, accelerated or retarded, in order to maintain that degree of synchronism in the action of the pendu- lums, and similarity of position, which are necessary for success of the telegraphic opera- tions. When the pendulum at b is correctly timed in its motions, there will be visible two sparks on the left-hand side, and one spark on the right-hand side, of the conduct- ing groove at k, k, at station b, equal distance from the centre of vibration ; but when this pendulum is not in its proper position or motion, these sparks can be seen at other places along the groove, h^ and u2, at both stations are signal-making wires; and g', g2, at both stations, are signal-receiving wirea These signal wires are to be sup- posed as numerous in each set as the number of different signals desired to be used — say not less than the letters of the alphabet; a smaller number is, however, shown in the drawing for distinctness' sake. All the signal-receiving wires reach into the groove or pathways p, s, p, in such a manner, that the spring f shall touch and slide over the flattened faces or ends of these wires in succession each time the pendulum moves from right to left The signal-making wires on the contrary, 628 ELECTRO-GILDING. I rii ' II .' stand a little off, out of the groove or pathway, but are intended to be so mounted that each may be raised with the pressure of the finger, and brought into the line of the groove or pathway, to be touched by the spring f, when the pendulum swings from left to right All these signal wires are united by one end to the conductor l, l, but are free and independent at the other end. The free end of the signal-receiving wires may have a width of half an inch, more or less, where f passes over them. The cor- responding ends of the signal-making wires may be put on edge or line; so that the signal-making wires can be touched by f but for a moment, whilst the signal-receiving wires will be touched for a sensible time by f, in passing over them. Under these circumstances, if any one of the signal-making wires ill, at station a, be touched and brought into contact with the end f, of the vibrating pendulum, a con- ducting circuit or electric current will be established for the moment, the correspond- ing pendulum at station b will be in front of the group of signal-receiving wires nl of that station. Therefore, from the electric circuit existing for that moment of contact, there would be a spark visible upon the flattened end of that one of the signal-receiving wires which corresponds to that one of the signal-making wires at the other station, which may have been pressed upon and brought into the pathway of f; all these signal wires in each set being marked by and signifying the different letters of the alphabet, Ac It is obvious, that if the left-hand wire of each set be marked a, the next b, next f, Ac, then, should a, 6, or c, of a signal-making group h^, station a, be pressed upon and touched by f, this act will be known at station b, by the appearance of a spark on the end of that one of the signal-receiving wires a, 6, or c, of group u^ station b, correspond- ing to that wire which may have been so touched at station a. Thus, at will, can any- signal or letter be sent from station a to station b, and during the operation of signal- making, by one person at station a, to another at station b. It will now be seen that another person, or the same person at station b, by the use of the wires n^, can telegraph in reply to station a, by making use of the set of wires ill of each station, in a manner similar to those in which the wires h1, before described, wefe used. Suppose that the time of a double vibration of these pendulums is equal to the time necessary for con- veniently making and observing a signal, then, by the use of the four seta of signal wires above named, a person may send to or receive signals from or between stations a and B reciprocally; or four persons may be continually and simultaneously employed in making and receiving signals at each station. The use of these signal- wires referred to, as able to employ four persons in continual telegraphic intercourses, will in no way interfere with the simultaneous employment of two or four other operators using the other signal wires on the right-hand half of the vibrations marked u2 and g2; so also by lengthening out the ends of the pendulum rods, or increasing the angular mo- tion of the pendulums, more ppace or places may be had for carrying out a larger num- ber of telegraphic operations indefinitely. It has been said that the pendulum at station b may be kept adjusted to the motions of the jegulating pendulum, by the appearance of sparks at k, k; but this synchronism may be more perfectly maintained by using any of the known forms of electro-magnets. In the above illustration the electric spark from an electrical machine has for simplicity been chosen as the visible signal ; but should it be desired to make signals by the hydro-electric current and the deflection of a needle, then each one of the signal-receiv- ing wires, before uniting with the common conductor l, may be lengthened out suf- ficiently to form the coil of a galvanometer ; and the current passing through any one of these wires can make itself known, or a signal be so given, by the deflection of the needle of the galvanometer belonging to that particular signal-receiving wire so signal- ized ; or, in like manner, those prolonged signal-receiving wires may each one enclose a bar of iron, in place of a magnetic needle, so as to have an electro-magnet and keeper belonging to each one of these wires ; then the passage of the current through any of the wires may give magnetism to the bar, or actuate the magnet or its keeper ; and from this motion the signals may be perceived, or recorded and printed in any con- venient form. From the above explanations, it will be obvious that divers stations and complex systems of telegraphic lines of communications can be established on the prin- ciple of this invention ; and it will be also understood, that the invention is susceptible of an indefinite number of modifications or forms, as respects the apparatus employed in carrying it into use. The patentee claims, rendering available conducting power of electric telegraph wires, so that they may transmit one or more electric currents (in the same or opposite directions) during the time that must necessarily elapse between the transmission of succeeding signals which have reference to one and the same communi- cation. — Newton's Journal, xl. 36. ELECTRO-GILDING AND SILVERING. According to Le Docteur Philipp, the vessel required for this purpose should be made of the same material as that commonly employed for flower-pots: before being used it must be tested in the follow- ing manner : On being filled with water, if it becomes simply damp, without allowing the water to filter through it^ it is fit for use, but not otherwise. This vessel is sur* ELECTRO-METALLURGY. 629 rounded by a cylinder of zinc, and then introduced into another vessel (a wooden tub for instance) containing dilute sulphuric acid. The earthen vessel is intended to con- tain the solution of gold or silver, and is furnished with a web of copper wire, which is made to communicate with the zinc by means of one or more conducting wires. The objects to be gilt or silvered are placed upon the net-work. The earthen vessel contain- ing a zinc cylinder, and some hydrochloric acid, is introduced into another vessel, con- taining the solution of gold or silver, placed in the centre of a wire web partition, which communicates with the zinc cylinder by means of a conducting wire. In the first case, the articles which are to receive the thickest coating are placed nearest the outer sides of the apparatus; in the second, nearest to the earthen vessel; in both cases it is advisable to shift their position occasionally. By combining these different arrangements, the deposit obtained is more abundant, and more equally distributed upon the surface to be gilded or to be silvered. For this purpose an opening is made in the centre of the web in which the zinc cylinder is inserted, with connecting wires to the web. When the articles to be operated upon can be easily suspended from a given point, the web of the apparatus may be made with wider meshes, and the articles suspended vertically between them. Dr. Philipp prefers a single galvanic arrangement to a battery, as it affords more solid deposition. ELECTRO-METALLURGY. By this elegant art perfectly exact copies of any object can be made in copper, silver, gold, and some other metals, through the agency of voltaic electricity. The earliest application of this kind seems to have been prac- tised about 16 years ago, by Mr. Bessemer, of Camden Town, London, who deposited a coating of copper on lead castings, so as to produce antique heads in relief, about 8 or 4 inches in size. He contented himself with forming a few such ornaments for his mantelpiece; and though he made no secret of his purpose, he published nothing upon the subject A letter of the 22d of May, 1839, written by Mr. J. C. Jordan, which ap- peared m the Mechanics' Mag. for June 8, following, contains the first printed notice of the manipulation requisite for obtaining electro-metallic casts; and to this gentleman, there- fore, the world is indebted for the first discovery of this new and important application of science to the uses of life. It appears that Mr. Jordan had made his experiments in the preceding summer, and having become otherwise busily occupied, did not think of publishing till he observed a vague statement in the Journals, that Professor Jacobi, of »t Petersburg, had done something of the same kind. Mr. Jordan's apparatus consisted of a glass tube closed at one extremity with a plug of plaster of Paris, and nearly filled with a solution of sulphate of copper. This tube, and its contents, were immersed in a solution of common salt. A plate of copper was plunged in the cupreous solution, and was connected by means of a wire and solder, with a zinc plate dipped in the brine. A slow electric action was thus established through the moist plaster, and copper was deposited on the metal in a thin plate, corresponding to the former in smoothness and polish ; so that when he used an engraved metal matrix, he obtained an impression of it by this electric agency. " On detaching the precipitated metal," says he, " the most delicate and superficial markings, from the fine particles of powder used in polishing to the deeper touches of a needle or graver, exhibited their corres- pondent impressions in relief with great fidelity. It is, therefore, evident that this principle will admit of improvement, and that casts and moulds may be obtained from any form of copper. This rendered it probable that impressions might be obtained from those other metals having an electro-negative relation to the zinc plate of the battery. With this view a common printing type was substituted for the copper-plate, and treated in the same manner. This, also, was successful ; the reduced copper coated that portion of the type immersed in the solution. This, when removed, was found to be a perfect matrix, and might be employed for the purpose of casting, where time is not an object. Casts may probably be obtained from a plaster surface sur- rounding a plate of copper, &.c." On the 12th of September following the above publication, Mr. Thomas Spencer read a paper " On Voltaic Electricity applied to the purpose of working in Metal," before the Polytechnic Society of Liverpool ; which he had intended to present to the British Association at Birmingham in the preceding August, but not being well received there, he exhibited merely some electro-metallic casts which he had prepared. The Bociety published Mr. Spencer's paper, and thereby served to give rapid diflusion to the practice of electro-metallurgy. One of the most successful cultivators of this art has been Mr. C. V. Walker, lecretarj' to the London Electrical Society. He has published an ingenious little work in two parts, entitled Electrotype Manipulation, where he presents, in a lucid manner, the theory and practice of working in metals, by precipitating them from their solutions through the agency of voltaic electricity. His first part is devoted to the explanation of principles, to the preparation of moulds, to the description of the voltaic apparatus to be used, to bronzing, to coating busts with copper, to the multiplication of engraved plates, and to the deposition of other metals. 630 ELECTRO-METALLURGY. \t n ^ « F^g. 479. represents a si!>gle-cell voltaic apparatus for electro-metallui^y. z is 479 a rod of amalgamated zinc, m is the mould on which the metal is to be deposited; tr, is the wire joining them; c is a strong solution of sulphate of copper in the- lau-ge vessel; p, is a tube or cylinder of porous earthenware, standing in the other, and containing dilute sulphuric acid. The solution of blue vitriol is kept saturated, during the progress of its depositing copper, by ^ piling crystals of the salt upon the shelf, shown by the dots under p. The mould to be coated should not be too small in reference to the surface of zinc under voltaic action. The time for the depo- sition to be effected depends upon the temperature; and is less the higher this is within certain limits; and at a freezing temperature it ceases almost entirely. When a mould of fusible metal is used, it should not be placed in the voltaic apparatus till everything is arranged, otherwise oxide will be deposited upon it, and spoil the effect. When the circuit is completed the mould may be im- mersed, but not before. Wax moulds are rendered electric con- ductors, and thereby depositors as follows : After breathing on the wax, rub its surface with a soft brush dipped in plumbago ; breathing and rubbing alternately till the surface be uniformly covered. Attach a clean wire to the back of the mould, connecting it by plumbago with the blackened wax. Sealing-wax is coated in like manner. Casts of Paris plaster are first well im- bued with melted wax or tallow, and then black-leaded. Objects in Paris plaster should be thoroughly penetrated with hot water, but not wet on the surface, before wax casts are made from them. Moulds are best taken from medals in stearine (stearic acid). For plating and gilding by electro-chemical agency, the following simple plan of apparatus is used. Fig. 480, is a rectangular porcelain vessel, which contains in its centre a porous cell for containing the solution of oxide of silver or gold, by means of cyanide of potassium ; and this porous cell is surrounded at a little distance by a similarly formed vessel of zinc. The connexion is formed between the zinc and the suspended object to be coated, either by a pinching screw, or by the pressure of its weight upon the wire. The dilute acid which excites the zinc should, in this case, be very weak, in reference to the strength of the cyanide solution, which ■hould be recruited occasionally by the addition of oxide. It has been found that with cyanide solutions of gold and shfer in the electro- chemical apparatus, the nascent cyanogen at the positive pole or plate, in a decon^ position cell, will act upon and dissolve gold and silver. Two oi three of Daniell*i cylindric cells, as shown at a in fig. 481, of a pint size, for actij^^ upon solutions of jold or silver, will in general suffice. The decomposition cell b is made of glass or porcelain. The zinc may be amalgamated, and excited with brine ; the copper cell contains, as usual, a solution of blue vitriol. To the end of the wire attached to the copper cylinder of the battery, a plate of silver or gold is affixed ; and to the end of the wire attached to the zinc cylinder is affixed the mould, or surface, to be plated or gilt. The plates of silver or gold and zinc should be placed face to face as shown in the figure in the decomposition cell ; which is filled by the cyanide solution. A certain degree Df heat favors the piocesses of electro-gilding and plating. The surface is dead as first obtained, but it may be easily polished with leather and plaie-powder, and burnished in whole or in parts with a steel or agate tool. ELECTRO-METALL URGY. 631 In March, 1840, Messrs. Elkington obtained a patent for the use of pru»date of potanh, as a solvent for the oxides "of gold and silver in the electro-chemical apparatus for plating and gilding metals. They also « sometimes employ a solution of protoxide (purple of Cassius) in the muriates of potash, &c." The chemical misnomers, in their specification, are very remarkable, and do great discredit to the person employed to draw it up. Prussiate of potash is the ordinary commercial name of a saU very different from the cyanide of potassium — the substance really meant by the patentees — and the purple of Cassius is very different from protoxide of gold. In plating or gilding great care must be bestowed in making the articles clean, bright, and perfj2tly free from the least film of grease. For this purpose, they should be boiled in a solution of caustic alkali, then scoured with sand and water, next dipped into a dilute acid, and finally rinsed with water. A solution of the nitrate or cyanide of mercury may also be used with advantage for cleaning surfaces. The following metals have been deposited by electro-chemistry : — Gold, platinum, silver, copper, zinc, nickel, antimony, bismuth, cobalt, palladium, cadmium, lead, and tin ; of these, the first five are the most important and valuable. The gilding solution may be prepared by placing slips or sheets of gold in a solution of cyanide of potassium, and attaching to the negative pole of a voltaic battery, a small plate of gold, but to the positive pole a much larger one ; whereby the latter com- bines with the cyanogen, under the influence of positive electricity, and forms a solu- tion. Or, oxide of gold, precipitated from the chloride by magnesia, may be dissolved in the solution of the cyanide. For making copper medals, &c., a plate of amalgamated zinc is to be put into a vessel of unglazed earthenware, or of any other porous substance, filled with dilute sul- phuric acid ; which vessel is set into a trough of glass, glazed pottery, or pitched wood, containing blue vitriol in the state of solution, as well as in the state of crjstals upon a perforated shelf, near the surface of the liquid. The moulds to be covered with copper are to be attached by a copper wire to the zinc plate. The surface of zinc excited by the acid should be equal to that of the moulds ; with which view a piece of zinc, equivalent in size to the mould, should be suspended in front of it. • r r • i For depositing copper upon iron, Messrs. Elkington use a solution of ferrocyanide of copper in cyanide of potassium in the decomposition trough, instead of sulphate of coppet, neutralized from time to time with a little caustic alkali, as in the commoE practice ot making medals, &c., of copper. I should imagine that the black oxide of copper dissolved in solution of cyanide of potassium would answer better ; as the iron in the ferrocyanide might be rather injurious. The iron to be coppered being previously well cleaned from rust, &c., with the aid of a dilute acid, is to be plunged into the cyanide solution heated to 120° Fahrenheit, and connected by a wire with the negative pole of a voltaic battery, as formerly described. In from five to ten minutes, the iron will be completely coated. It is then to be scoured with sand, and plunged into solution of sulphate of copper ; whereby it will show black spots wherever there are any defec- tive places. In this case, it is to be cleaned and replaced under the cyanide solution, in the decomposition cell for a minute or two. Zinc may be deposited from a solution of its sulphate by a like arrangement. Metallic cloth may be made as follows : — On a plate of copper attach quite smoothly a stout linen, cotton, or woollen cloth, and connect the plate, with the negative pole of a voltaic battery : then immerse it in a solution of copper or other metal, connecting a piece of the same metal as that in the solution with the positive pole ; decomposition takes place, and the separated metallic particles in their progress toward the metal plate or negative pole, insinuate themselves into the pores of the tissue, and form a com- plete sheet of flexible metal. Lace is metallized by coating it with plumbago, and then subjecting it to the electro-metallurgic process. The gilding solution should be used in the electric process at a temperature of 130* F. The more intense the electric power, the denser and harder is the metallic coat deposited. Metallic silver may be combined with cyanogen by subjecting it to the joint action of a solution of cyanide of potassium and positive electricity. Or cyanide of silver may be precipitated from the nitrate by a little cyanide of potassium, and afterward dissolved by means of an excess of cyanide of potassium. The quantity of electric power or sur- face-size of the battery should in all cases be proportioned to the surface of the articles to be placed or gilt, and the electric intensity or number of sets of jars proportioned to the density of the solution. Plating is accomplished in from 4 to 6 hours. The articles ihould be weighed before and after this operation, to ascertain how much silver they kave taken on. Messrs. Elkington make their moulds with wax, combined with a little phosphorus. Which reduces upon their surfaces a thin film of gold or silver, from solutions of these f 632 ELECTRO-METALLURGY. ELECTROTYPIE. 633 , 1 1 i i 1 1 1 '':! jj I 1 l! i i i)i( metals, which films are hetter than the black-leaded surfaces for receiving the copper deposit. They also recommend to add a little alkali to the solution of sulphate of copper, intended to afford a deposite of metal. The single cell, first described above, is best adapted for this purpose. M . Ruolz employs for gilding, a solution of snlpharet of gold in sulphuret of p^^tas- sium, which he prepares by precipitating a solution of gold in aqua regia, by sulphu- retted hydrogen, and redissolving the precipitate with sulphuret of potassium. By the use of this solution of gold, he obtains a very beautiful and solid gilding, and at less expense than with cyanide of potassium. Every metal which is a negative electrode to gold may be gilded. Platinizing is effected best by means of a solution of the potash-chloride of platinum m caustic potash. 1 milligramme (0-015 grain) covers completely a surface of 50 square centimeters (2 inches square) ; the film of platinum is only one hundridth of a niilligramme thick. M. BoBttger has shown that we may easily tin copper and brass in the moist way by dissolvmg peroxide of tin (putty) in hydrate of potash (caustic potash ley), putting at the bottom of the vessel holding that solution some turnings of tin, setting the piece of copper or brass upon the turnings, and makinar the liquor boil. An electric current is produced by the contact of the dissimilar metals ; and as the tin is withdrawn by the copper or brass from the solution, it is restored to it by the turnings. Zinking may be done in the same way ; by putting pieces of zinc into a concentrated solution of chlorine, by setting the piece of metal to be zinked in contact with these pieces, and applying heat to the vessel containing the whole. For certain new methods of constructing and arranging voltaic batteries for electro- inetallurgic operations, a patent was obtained by Dr. Leeson in June, 1842. Fig. 482, is a longitudinal section of the batterj-, and ^g. 483, a plan view of the frame to which the metal plates are attached, o is a rectangular wooden trough, containing a wooden frame b, formed with vertical grooves in its sides, to receive a series of porous cells c, c, c. The plates of the battery are suspended in the fluid or fluids by brass lorks d, d, fastened to a wooden frame e, e, which rests upon the trough a, and is con- nected to the other frame 6, by two pins/, when they are required to be raised together out of the trough a, a. The battery may be charged as usual with one or two fluids ; one of them in the latter ease being contained in the porous cells c, c, e : and plates of copper and zinc or any other suitable metals may be employed. ' The second improvement consists in cleaning copper and zinc plates after they have been used in a battery, by the employment of a voltaic battery; and also in amalga- 483 482 mating or coating with mercury the surfaces of zinc plates, by the same means to render them suitable for being used in the construction of the voltaic apparatus. The third improvement consists in exciting electricity by a combination of nitric, sulphuric, or muriatic acid, with any of the following substances; viz, impure ammoni- acl or lime liquor of the gas works, solutions of alkaline and earthy sulphurets, the alkalies and their carbonates, or lastly, the acidulous sulphate of iron generated from ^"^ AnouVer^f Dr. Leeson's manifold improvements for depositing metallic alloys con- siste in the employment of one battery, " with the alternating cathode, represented m fig 484 It is composed of a beam, a, mounted on the shaft, 6, which turns in bearings carried by standards, c ; the beam communicates with the anode of the battery by the wire, d, and a vibrating motion is given to it by the rod, e, from the shatt,/, which is driven by an electro-magnetic engine, or any other suitable prime mover, g, g, are two vessels containing mercury, connected by wires, h, h, with the cathode plates ot the two metals composing the alloy (but if the alloy is to consist of more than two metals, then more vessels, a, will be required, one for each cathode plate); these plates are immersed in a solution composed of similar salts of the diflferent metals to be deposited, to«rether with the anode, or surface to be deposited upon, which is connected by a wire wfth the cathode of the battery. A communication is established between the two cathode plates, or supply of metals, and the anode of the battery, by means of the rods, t i which are caused, by the vibration of the beam, a, to dip alternately into either the one or the other of the vessels, g; and thus each metal will be deposited on the article to be coated during the time that the connection is established between it and the bat- tery, by the immersion of its rod into the vessel of mercury. The relative proportions of the two metals is adjusted by lengthening or shortening the rods, i, i, as shown m the fi<«-ure, so that they may be immersed for a longer or shorter period in the mercury. Where the electrical current enters the electrolyte, is the anode; where it leads it, is the cathode. . . _ The patentee describes ten other improvements, which seem to be ingenious, tsee Newton*s Journal, xxii. 292. tv i i i. a ELECrrROTYPIE by TnERMO-ELECTRicrry. 1. For silvering.— VissoUe 1 troy ponna of silver in nitiic acid, dilute with a gallon of water, precipitate the silver by solution of carbonate of soda (1 lib.) at 100^ Fahr. ; wash the precipitate on the filter with warm water. In another vessel dissolve 8 libs, of hyposulphite of soda in 2| gallons of water at 100°, add 1 lib. of carbonate of soda with the carbonate of silver, stirring until the silver be dissolved. Filter the solution for use. It is advantageous to add 1 lib. avoirdupois of hyposulphite, and one-third of a pound of carbonate of soda for every pound troy of silver that may be deposited. ^ 2. Gold solution,— One ounce troy of fine gold is dissolved in nitro-muriatic acid, and the solution is evaporated till it assumes a deep red color, and crystallizes upon cool- in«'. Dilute with a pint of pure water and filter. Heat this solution to about 200° Faiir. and precipitate the gold by water of ammonia. Wash the precipitate well on the filter with hot water. Dissolve this gold in 1 gallon of water containing 8 ounces of hyposulphite of soda, and boil together for an hour. The solution when filtered is fit for use. In gilding, this solution may be warmed to about 130° Fahr. A small anode of gold, of about one-tenth the size of the article to be gilded, and a current of two pairs of common galvanic plates, are used. 3. Copper solution.— Dissolve 1 pound of carbonate of copper m 8 pounds of hypo- sulphite of soda, and 1 pound of carbonate of soda dissolved in 2^ gallons of distilled water at 100° Fahr., or thereabouts, and filtered to obtain a clear solution. It is then fit for use, with currents of electricity at 100° Fahr. ^ Description of the thermo-electric battery.— 100 pieces of German silver, containing from 20 to 25 per cent of nickel, and 100 pieces of iron, each piece being 1 inch broad, 1 foot long, and one-eighth of an inch in thickness. These 200 pieces are soldered to each other, so that iron is always combined with German silver. To get a compact form, 10 rows must be first arranged (every one of 20 pieces or 10 pairs), and these rows must be so soldered tx) each other that they are parallel, and the whole take the form of a square ; taking care that the several pieces are soldered totrether in such a way that iron will always be in connection with German silver. When the whole is united, it is placed in a rim or frame of iron y>late, 1 foot 2 inf'VJs high but so that the metals do not touch each other, nor the iron rim or frame, and fill the rim with plaster of Paris or clay, so that all soldered parts of the series of plates or bars are uncovered, that is, the under ends 1 inch, and the upper ends 3 inches. The clay is covered at the surface with a laver of pilch. The frame containing the series of bars or plates, is so placed that the'lower end of the series (1 inch) dip into a sand bath which is heated nearly to redness. The upper ends (3 inches) are to 634 ELEMENTS. EMBALMING. 635 f ' ii be kept as cold as possible, and for this purpose a current of cold water is caused to flow from one vessel over this battery to another vessel. The upper end of the metals v3 inches) may be covered with a lac or varnish. There is an anode wire leading from the German silver plate ; and an artule wire leading from the iron plate. The thermo-electric apparatus is intended for the deposition of metals, from the above described solutions ELEMENTS (Eng. and Fr.; Grundstoffe, Germ.) Tlie ancients considered fire, air, water, and earth, as simple substances, essential to the constitution of all terrestrial bemgs. This hypothesis, evidently incompatible with modern chemical discovery, may be supposed to correspond, however, to the four states in which matter seems to exist ; namely, 1. the unconfinable powers or fluids,— caloric, light, electricity ; 2. pon- derable gases, or elastic fluids; 3. liquids; 4. solids. The three elements of the alche- mists, salt^ earth, mercury, were, in their sense of the words, mere phantasms. I Deaoininatioa of the Substances. Aluminium . . . Antimony . . . Arsenicum . . . Barium • . . . Bismuth - . . . Boron • . . . Brome - . . . Cadmium . . . Calcium - - . . Carbon - . . . Cerium (Marignac) - Chlorine - . . . Chromium . . . Cobalt - - . . Copper - . . . Didymium (Marignac) Erbium - . . Fluorine - . - . Gold . . . . Glucinium - - . Hydrogen . . . Iodine • . . . Iridium - . . . Iron . . . . Lantbanium (Marignac) Lead . . . . Lithium - . . . Magnesium . . . Manganese . . . Mercury - - - . Molybdenum - . . Nickel - . . . Niobium .... Nitrogen- . . . Norium - - . . Osmium • . . . Oxygen .... Palladium ... Pelopium ... Phosphorus ... Platinum ... Potassium ... Rhodium ... iluthenium, according to Claus Selenium ... Silicium - . . . Silver - - . . Sodium • . . . Sulphur .... Strontium ... Tantaliam ... Tellurium ... Terbium .... Thorium . . . - Titanium- ... Tin .... Tungsten ... Uranium .... Vanadium . . - Yttrium .... Zinc .... Zirconium ... c .o E Al. Sb. As. Ba. Bi. B. Br. Cd. Ca. C. Ce. CI. Cr. Co. Cu. D. E. Fl. Au. G. H. I. Ir. Fe. La. Pb, LI Mg. Mn. Hg. Mo. Ni. Nb. N. No. Os. O. Pd. Pe. P. Pt. K. R. Ru. Se. SL Ag. Na. S. Sr. Ta. Te. Tb. Th. Ti. Sn. W. u. V. Y. Zn. Zr. I. Equivalents. 0=100. 170-900 16I2£K)3 938-800 «55 290 1330-377 136 204 999-620 696767 251-651 75-120 590-800 443 280 328-870 368.650 395-600 620000 2a5433 24.58 330 87-124 12-480 1585-992 1232-080 350-527 588 -(100 1294-645 81660 158140 344.684 1251-290 596-100 S69 330 175-060 1242-624 100 000 655.477 892-041 1232080 488-856 651-962 6.51-000 495-285 277-778 1349-660 289-729 200-750 545 929 1148 365 801-760 743 860 301-550 735-294 1188-360 742-875 856-892 406-591 419-728 H=l. 13 694 129-269 75-224 68-533 106-600 10-914 80-098 55 831 20-164 6-019 47-261 35517 26 352 29-539 31-699 49-600 18-865 196 982 69(il 1-000 127082 98-724 28-087 47-(«0 103-738 6-543 12671 27-619 100-026 47-764 29-594 14-027 99-569 8-000 53-323 31.414 98-724 39171 52-240 52-163 39 686 22 258 108146 23215 16-086 43744 92-016 64-244 59-604 24-158 58-918 95-220 59-525 68-661 32-579 33«32 II. Atomic Weights. O=I00. 170-9> w Ca. C. H. Fe. rr- Na. Sr. S. Equivalents. 0=100. 250-000 75000 12000 350-000 1250 000 400-000 287-170 M8-020 200-000 H=l Atomic Weij^hta. 20000 6-000 1000 23-000 100-(HX) 32-024 22-973 43-841 16000 OailOO. H=rl. 250-000 75000 6250 250-100 1250000 200-150 287-170 548020 200-000 40-000 12000 1-000 56-000 200-000 32-024 45-046 87«82 32i)06 Within the last few years the following atomic weights have been revised: — Barium - Calcium - Chromiunti Chromium Fluorine Magnesium Magnesium Magnesium Molybdenum Molybdenum Ba. 856*770 Marignac. Ca. 350.000 Erdm. and March. Cr. 833-500 Lefort Cr. 835 091 Moberg. Fl. 237-500 Louyet Mg. 162-550 Jacquelain. Mg. 164-490 Svanberg. Mg. 160.000 March, and Scheer. Mo. 574-750 Berlin. Mo. 574-829 Svanb. and Struve. W. 1150-780 Schneider. Tungsten ELEMI is a resin which exudes from incisions made during dry weather through the bark of the amyris elemifera, a tree which grows in South America and Brazil. It comes to us in yellow, tender, transparent lumps, which readily soften by the heat of the hand. They have a strong aromatic odor, a hot spicy taste, and contain 12| per cent of etherous oil. The crystalline resin of elemi has been called Elemine. It ia used in making lacquer, to give toughness to the varnish. . , , , , ELUTRIATE. \Soutirer, Fr.; Schlemmen, Germ.) When an insoluble pulve- rulent matter, like whitening or ground flints, is diflfused through a large body of water, and the mixture is allowed to settle for a little, the larger particles will subside. If the supernatant liquid be now carefully decanted, or run off, with a syphon, it wUl contain an impalpable powder, which on repose will collect at the bottom, and may be taken out to dry. This process is called elutriation. EL VAN. The name given by the Cornish miners to porphyry, as also to the heteroo-eneous rocky masses which occur in the granite or in the clay slate, deranging the direction of their metallic veins, or even the mineral strata ; but elvan generally indicates a felspar porphyry. . EMBALMIiSG. {Embaument, Fr. ; Einbalsamen, Germ.) Is an operation in i^hich balsams {baumes, Fr.) were employed to preserve human corpses from putrefac- tion; whence the name. • xu v j* * The ancient Egyptians had recourse to this process for preserving the boilies ol numerous families, and even of the animals which they loved or worshipped. An excellent account of their methods is given in Mr. Pettigrew's work upon Mummies. Modern chemistry has made us acquainted with many means of counteracting putre- I* n a WjA \\\ ' « : f 636 EMBOSSING CLOTH. faction more simple and efBeacions than the Egyptian system of salting, 8moV;i».gi spicing, and bitumenizing. See Putrefactiox. EMBOSSING CLOTH. Mr. Tbunas Greig, of Rose Bank, near Bury, patented an invention, in November, 1835, which consists in an ingenious construction of ma- chinery for both embossing and printing silk, cotton, woollen cloth, paper, and othei fabrics, in one or more colors, at one operation. Figs. 486, 486 represent three distinct pri nting cylinders of copper, or other suitabU '^ ~ material, a, d, c, with their necessary appen- danges for printing three different colors up>on the fabric as it passes through the machine either of these cylinder! A, B, or c, may be em« ployed as an embossing cylinder, without per« forming the printing pro* cess, or may be made t« effect both operations at the same time. The fabric or goods to be operated upon be- ing first wound tightly upon a roller, that roller is to be mounted upon an axle or pivot, bearing in arms or brackets at the back of the machine, as shown at d. From this roller the fabric a a a a is conducted be- tween tension rails, and passed under the bed cylinder or paper bowl E, and from thence pro- ceeds over a carrier roller F, and over steam boxes not shown in the draw- ing, or it may be con- ducted into a hot room, for the purpose of drying the colors. The cylinders A, b, and c, havinar neither en- graved or raised surfaces, are connected to feeding rollers b b by revolving in the ink or colored troughs c c c ; or endless ts, called sieves, may be employed, as in ordinary printing machines, for supplying the color, when the device on the surface of the cylinders is raised : these cylinders may be famished with doctors or scrapers when required, or the same may be applied to the endless felts. The blocks have adjustable screws g g, for the purpose of bringing the cylinders np against the paper bowl, with any required degree of pressure : the cylinder b is support- ed by its gudgeons running in blocks, which blocks slide in the lower parts of the lide frames, and are connected to perpendicular rods t, having adjustable screw nuts. The lower parts of these rods bear upon weighted levers fe fe, extending in front of the Hachme ; and by increasing the weights 1 1, any degree of upward pressure may be givea to the cylinder b. The color boxes or troughs c c Cy carrying the feeding rollers bbb, are fixed on boards «rhich slide in grooves in the side frames, and the rollers are adjusted and brought into contact with the surface of the printing cylinders by screws. If a back cloth should be required to be introduced between the cylindrical bed or Daper bowl e, and the fabric a a a, as the ordinary felt or blanket, it may, for printing and embossing cotton, silk, or paper, be of linen or cotton ; but if woollen goods are to be operated upon, a cap of felt, or some such material, must be bound round the paper EMBOSSING CLOTH. 637 bowl, and the felt or blanket must be used for the black cloth, which is to be conducted over the rollers h and l For the purpose of embossing the fabric, either of the rollers a, b, or c, may be employed, observing that the surface of the roller must be cut, so as to leave the pallera or device elevated for embossing velvets, plain cloths, and papers ; but for woollens the device must be excavated, that is, cut in recess. The pattern of the embossing cylinder will, by the operation, be partially marked through the fabric on to the surface of the paper bowl e ; to obliterate which marks from the surface of the bowl, as it revolves, the iron cylinder roller g is employed ; but as in the embossing of the same patterns on paper, a counter roller is required to produce the pattern perfectly, the iron roller is in that case dispensed with, the impres- sion given to the paper bowl being required to be retained on its surface until the opera- tion is finished. In this case the relative circumferences of the embossing cylinder, and of the paper bowl, must be exactly proportioned to each other ; that is, the circumference of the bowl must be equal, exactly, to a given number of circumferences of the embossing cylinder, very accurately measured, in order to preserve a perfect register or coincidence, as they continue revolving between the pattern on the surface of the embossing cylinder, and that indented into the surface of the paper bowl. The axle of the paper bowl e, turns in brasses fitted into slots in the side frames, ana it may be raised by hand from its bearings when required, by a lever /c, extending in front. This lever is affixed to the end of a horizontal shaft l, l, crossing the machine seen in the figures, at the bac.i of which shaft there are two segment levers p, p, to which bent rods q, q, are attached, having hooks at their lower ends, passed under the axle of the bowl. At the reverse end of the shaft l, a ratchet-wheel r, is affixed, and a pall or click mounted on the side of the frame takes into the teeth of the wheel r, and thereby holds up the paper bowl when required. When the iron roller g, is to be brought into operation, the vertical screws /, t, mount- ed in the upper parts of the side frames, are turned, in order to bring down the brasses M, which carry the axle of that roller and slide in slots in the side frames. The cylinders a, b, and c, are represented hollow, and may be kept at any desired tem- perature during the operation of printing, by introducing steam into them ; and under the color boxes c, c, c, hollow chambers are also made for the same purpose. The degree of temperature required to be given to these must depend upon the nature of the coloring material, and of the goods operated upon. For the purpose of conducting steam to these hollow cylinders and color boxes, pipes, as shown at r, v, Vy are attached, which lead from a steam boiler. But when either of these cylinders is employed for embossing alone, or for embossing and printing at the same time, and particularly for some kinds of goods where a higher temperature may be required, a red-hot heater is then introduced into the hollow cylinder in place of steam. If the cylinder b is employed as the embossing cylinder, and it is not intended to print the fabric by that cylinder simultaneously with the operation of embossing, the feeding roller 6, must be removed, and also the color box c, belonging to that cylin- der ; and the cylinders a and c, are to be employed for printing the fabric, the one applying the color before the embossing is efl"ected, the other after it. It is however to be remarked, that if a, and c, are to print colors on the fabric, and b to emboss it, in that case it is preferred, where the pattern would allow it. a and c, are wooden roll, ers having the pattern upon their surfaces, and not metal, as the embossing cylinders must of necessity be. It will be perceived that this machine will print one, two, or three colors at the same time, and that the operation of embossing may be performed simultaneously with the printing, by eithe." of the cylinders a, b, ore, or the operation may be performed consecu- tively by the cylinders, either preceding or succeeding each other. The situations of the doctors, when required to be used for removing any superfluous color from the surface of the printing cylinder, are shown at d, d, d ; those for removing any lint which may attach itself, at e, e, e. They are kept in their bearings by weighted levers and screws, and receive a slight lateral movement to and fro, by means of the ver- tical rod m, which is connected at top to an eccentric, on the end of the axle of the roller Kj and at its lower end to a horizontal rod mounted at the side of the frame ; lo this hori- zontal rod, arms are attached, which are connected to the respective doctors ; and thus, by the rotation of the eccentric, the doctors are made to slide laterally. When the cylinders a, b, or c, are employed for embossing only, those doctors will not be required. The driving power is communicated lo the machine from any first mover through the agency of the toothed gear, which gives rotatorv motion to the cylinder b, and from thence to the other cylinders a, and c, by toothed geer shown in Fig. 485. EMBOSSING OF LEATHER. Beautiful ornaments in basso-relievo for deco- rating the exteriors or interiors of buildings, medallions, picture-frames, cabinet work. 638 EMBROIDERING MACHINE. EMBROIDERING MACHINE. 639 liiii i' It I' t: V 640 EMBROIDERING MACHINE. gree, for each of these beams bears upon its end a small ratchet wheel ff, g ; the teeth of one of them being inclined in the opposite direction to those of the other. Besides this system of lower beams, there is another of two upper beams, which is however but imperfectly seen in the figure, on account of the interference of other parts in this view of the %naehine. One of these systems presents the web to the inferior needles, and the other to the upper needles. As the two beams are not in the aame vertical plane, the plane of the web would be presented obliquely to the needles were it not for a straight bar of iron, round whose edge the cloth passes, and which renders it vertical. The piece is kept in tension crosswise by small brass templets, to which the strings g" are attached, and by which it is pulled toward the sides of the frame f. It remains to show by what ingenious means this frame may be shifted in every possible direction. M. Ileilmann has employed for this purpose the pantograph which draughts- men use for reducing or enlarging their plans in determinate proportions. . .* *'/'. ^" ^fiO- 487) represents a parallelogram of which the four angles b, b\ f, b" are jointed in sucii a way that they may become very acute or very obtuse at pleasure, while the sides of course continue of the same length ; the sides b b' and b b" are pro- longed, the one to the point d, and the other to the point c, and these points c and d are chosen under the condition that in one of the positions of the parallelogram, the line c c? which joins them passes through the point/; this condition may be fulfilled in an infinite number of manners, since the position of the parallelogram remaining the same, we see that if we wished to shift the point d further from the point b\ it would be sufficient to bring the point c near enough to b", or vice versa ; but when we have once fixed upon the distance b' d, it is evident that the distance 6" c is its necessary consequence. Now the principle upon which the construction of the pantograph rests is this; it is sufficient that the three points d,/, and c be in a straight line, in one only of the positions of the parallelogram, in order that they shall remain always in a straight line in every position which can possibly be given to it We see in the figure that the side b c has a handle b" with which the workman puts the machine in action. To obtain more precision and solidity in work, the sides of the pantograph are joined, so that the middle of their thickness lies exactly in the vertical plane of the piece of goods, and that the axes of the joints are truly perpendicular to this plane, in which consequently all the displacements are effected. We arrive at this result by making fast to the superior great cross bar d" an elbow piece d'\ having a suitable projection, and to which is adapted in its turn the piece d\ which receives in a locket the extremity of the side b, a ; this piece d' is made fast to d" by a bolt, but it carries an oblong hole, anJ before screwing up the nut, we make the piece advance or recede, till the fulcrum point comes exactly into the plane of the web. This condition being fulfilled, we have merely to attach the frame to the angle /of the parallelogram, which is done by means of the piece f". It is now obvious that if the embroiderer takes the handle b" in his hand and makes the pantograph move in any direction whatever, the point / will describe a figure simi- lar to the figure described by the point c, and six times smaller, but the point / cannot move without the frame, and whatever is upon it moving also. Thus, in the movement of the pantograph, every point of the web describes a figure equal to that described by the point /, and consequently similar to that described by the point c, but six times smaller; the embroidered object being produced upon the cloth in the position of that of the pattern. It is sufficient therefore to give the embroidering operative who holds the handle b", a design six times greater than that to be executed by the machine, and to afford him at the same time a sure and easy means of tracing over with the point c, all the outlines of the pattern. For this purpose he adapts to c, perpendicularly to the plane of the parallelogram, a small style terminated by a point c', and he fixes the pattern upon a vertical tablet e, parallel to the plane of the stufi* and the parallelogram, and distant from it only by the length of the style c c" ; this tablet is carried by the iron rod e\ which is secured to a cast iron fool e', serving also for other purposes, as we shall presently see. The frame loaded with its beams and its cloth forms a pretty heavy mass, and as it must not swerve from its plane, it needs to be lightened in order that the operative may cause the point of the pantograph to pass along the tablet without strain- ing or uncertainty in its movements. M. Heilmann has accomplished these objects in the following way. A cord c attached to the side 6 c of the pantograph passes over a return pulley, and carries at its extremity, a weight which may be graduated at pleasure ; this weight equipoises the pantograph, and tends slightly to raise the frame. The lower side of the frame carries two rods h and h, each attached by two arms h hy a. little bent to the left; both of these are engaged in the grooves of a pulley. Through this mecha- nism a pressure can be exercised upon the frame from below upwards, which may be regulated at pleasure, and without preventing the frame from moving in all directions, it hinders it from deviating from the primitive plane to which the pantograph was adjust- ed. The length of the rods h ought to be equal to the amount of the lateral movement EMBROIDERING MACHINE. 641 of the frame. Two guides t t carried by two legs of cast iron, present vertical elite in which the lower part of the frame f' is engaged. Disposition of tJu carriages.— The two carriages, which are similar, are placed the one to the right, and the other to the left of the frame. The carriage itself is composed merely of a long hollow cylinder of cast iron l, carrying at either end a system of two grooved castors or pulleys l', which roll upon the horizontal rails k ; the pulleys are mount- ed upon a forked piece I', with two ends to receive the axes of the pulleys, and the piece r is itself bolted to a projecting ear Zcast upon the cylinder. This assemblage constitutes properly speaking the carriage, resting in a perfectly stable equilibrium upon the rails k, upon which it may be most easily moved backwards and forwards, carrying its train of needles to be passed or drawn through the cloth. M. Heilmann has contrived a mechanism by which the operative without budging from his place may conduct the carriages, and regulate as he pleases the extent of their course, as well as the rapidity of their movements. By turning the axes m" in the one direction or the other, the carriage may be made to approach to, or recede from the web. When one of the carriages has advanced to prick the needles into the stuff, the other is there to receive them; it lays hold of them with its pincers, pulls them through performs its course by withdrawing to stretch the thread, and close the stitch then it goes back with the needles to make its pricks in return. During these movements the first carriage remains at its post waiting the return of the second. Thus the two chariots make in succession an advance and a return, but they never move together. To effect these movements M. Heilmann has attached to the piece o' made fast to the two uprights a c and a d of the frame, a bent lever n o n' n" moveable round the point o ; the bend n' carries a toothed wheel o', and the extremity n" a toothed wheel o ; the four wheels m m' o' and o" have the same number of teeth and the same diJimeter; the two wheels o' and o" are fixed in reference to each other, so that it is sufficient to turn the handle n to make the wheel o" revolve, and consequently the wheel o' ; when the lever n o is vertical, the wheel o' touches neither the wheel m nor the wheel M'; but if it be inclined to the one side or the other, it brings the wheel o' alter- nately into gear with the wheel m or the wheel m'. As the operative has his two hands occupied, the one with the pantograph and the other with the handle of impulsion, he has merely his leet for acting upon the levern o, and as he has many other things to •.u :• r ^^^ adapted before him a system of two pedals, by which he executes with his leet a series of operations no less delicate than those which he executes with his bands. The pedals p are moveable round the axis p, and carry cords p' wound in an opposite direction upon the pulleys p' ; these pulleys are fixed upon a moveable shaft p", sun- ported upon one side by the prop e', and on the other in a piece k' attached to the two great uprights of the frame. In depressing the pedal p (now raised in the figure), the upper part of the shaft p' will turn from the left to the right, and the lever n o will be- come inchned so as to carry the wheel o' upon the wheel m', but at the same time the pedal which is now depressed will be raised, because its cord will be forced to wind itself upon Its pulley, as much as the other cord has unwound itself; and thus the apparatus will be ready to act in the opposite direction, when wanted. Disposition of the pincers.— The shaft l' carries, at regular intervals of a semi-diame- ter, the appendages q q cast upon it, upon which are fixed, by two bolts, the curved branches q destined to bear the whole mechanism of the pincers. When the pincers are opened by their appropriate leverage, and the half of the needle, which is pointed at each end, with the eye m the middle, enters the opening of its plate, it gets lod«^ed in an angular groove, which is less deep than the needle is thick, so that when the pincers are c osed, the upper jaw presses it into the groove. In this way the needle is firmly held alihough touched in only three points of its circumference. * Suppose, now, that all the pincers are mounted and adjusted at their proper distances upon their prismatic bar, forming the upper range of the right carriage. For opening ail the pincers there is a long plate of iron, u, capable of turning upon its axis, and which extends from the one end of the carriage to the other. This axis is (trried by a kind of forks which are bolted to the extremity of the branches q. By turning that axis the workman can open the pincers at pleasure, and they are again closed by sprin<'s. This movement is performed by his feet acting upon the pedals. The threads get stretched in proportion as the carriage is run out, but as this tension has no elastic play, inconveniences might ensue which are prevented by adapting to the carriage a mechanism by means of which all the threads are pressed at the same time by a weight susceptible of graduation. A little beneath the prismatic bar, wkich carries the pincers, we see m the figure a shaft, y, going from one end of the carriage to the other, and even a hltle beyond it ; this shaft is carried by pieces y which are fixed to the arms q, and in which it can turn. At its left end it carries two smaU bars y' and to', and T I 642 EMERY. EMERY. ' f at its right a single bar y\ and a counterweight (not visible in this view); the ends of the two bars y" are joined bj an iron wire somewhat stout and perfectly straight. When the carriage approaches the web, and before the iron wire can touch it, the little bar «• presses against a pin, u>', which rests upon it, and tends to raise it more and more. In ■what has preceded we have kept in view only the upper range of pincers and needles, but there is an inferior range quite similar, as the figure shows, at the lower ends of the arms q. In conclusion, it should be stated, that the operative does not follow slidingly with the pantograph the trace of the design which is upon the tablet or the picture, but he must stop the point of the style upon the point of the pattern into which the needle should enter, then remove it, and put it down again upon the point by which the needle ought to re-enter in coming from the other side of the piece, and so on in succession. To facilitate this kind of reading off, the pattern upon the tablet is composed of right lines terminated by the points for the entrance and return of the needle, so that the operative (usually a child) has continually under her eyes the series of broken lines which must be followed by the pantograph ; if she happens to quit this path an instant, without hav- ing left a mark of the point at which she had arrived, she is under the necessity of look- ing at the piece to see what has been already embroidered, and to find by this comparison the point at which she must resume her work, so as not to leave a Wank, or to repeat the same stitch. Explanation of figure. A, lower cross bars, which unite the legs of the two ends of the frame. a, the six feet of the front end of the frame. a', the six feet of the posterior end of the frame. a", curved pieces which unite the cross bars a" to thi uprights. b", handle of the pantograph. h h' h"y three of the angles of the pantograph. c, point of the side h b" on which the point is fixed, c", point of the pantograph. d", cross bar in form of a gutter, which unites the upper parts of the frame. d, fixed point, round which the pantograph turns. E, tablet upon which the pattern to be embroidered is put. e", support of that tablet. e, cord attached at one end to the side 6 c of the pantograph passing over a guide p•^ ley^ and carrying a weight at the other end. tf', iron rod by which the tablet k is joined to its support i'. F, F, uprights of the cloth-carrying frame. f', f', horizontal sides of the same frame, o, four roll beams. g", the piece of cloth. • and as soon as the whole surface is melted, the tray must be withdrawn with its platS; but slowly, lest the vitreous matter be cracked by sudden refrigeration. The enamel plate, when cold, is to be washed in very dilute nitric acid, and aller- wards in cold water, and a second coat of granular enamel paste is to be applied, with the requisite precautions. This, being passed through the fire, is to be treated in th« same way a third time, when the process will be found complete. Should any chinki happen to the enamel coat, they must be widened with a graver, and the space being filled with ground enamel, is to be repaired in the muffle. The plate, covered with a pure white enamel, requires always to be polished and smoothed with sandstone and water, particularly if the article have a plane surface ; and it is then finally glazed at the fire. The painting operation now follows. The artist prepares his enamel colors by pound- ing them in an agate mortar, with a pestle of agate, and grinding them on an agate slab, with oil of lavender, rendered viscid by exposure to the sun in a shallow vessel, loosely covered with gauze or glass. The grinding of two drachms of enamel pigment into an impalpable powder, will occupy a laborer a whole day. The painter should have along- side of him a stove in which a moderate fire is kept up, for drying his work whenever the figures are finished. It is then passed through the muffle. Enamelling at the Lamp. — The art of the lamp enameller is one of the most agreeable and amusing that we know. There is hardly a subject in enamel which may aOk be executed by the lamp-flame in very little time, and more or less perfectly, according to the dexterity of the artist, and his acquaintance with the principles of modelling. In working at the lamp, tubes and rods of glass and enamel must be provided, of all sizes and colors. The enamelling table is represented in Jig. 489, round which several workmen, with their lamps, may be placed, while the large double bellows d below is set a-blowing by • treadle moved with the foot. The flame of the lamp, when thus impelled by a powerful jet of air, acquires surprising intensity. The bent nozzles or tubes, a a a a, are made oC glass, and are drawn to points modified to the purpose of the enameller. Fig. 489 shows, in perspective, the lamp a of the enameller standing in its cistern b; the blowpipe c is seen projecting its flame obliquely upwards. The blowpipe is adjust- able in an elastic cork d, which fills up exactly the hole of the table into which it enters. When only one person is to work at a table provided with several lamps, he sits down at the same side with the pedal of the bellows; he takes out the other blowpipes, and plugt the holes in the table with solid corks. The lamp is made of copper or tin-plate, the wick of cotton threads, and either tallow or oU may he ised. Between the lamp and the workman a small board or sheel'.of white iron b, called the screen, is interposed to protect his eyes from the glare of light. The screen is fastened to the tabic by a wooden stem, and it throws its shadow on hia face. The enamelling workshop ought to admit little or no daylight, otherwise the artist, not perceiving his flame distinctly, would be apt to commit mistakes. It is impossible to describe all the manipulations of this ingenious art, over which taste and dexterity so entirely preside. But we may give an example. Suppose the enameller wishes to make a swan. He takes a tube of white enamel, seals one of its ends hermetically at his lamp, and while the matter is suflliciently hot., he blows on it a minikin flask, resembling the body of the bird ; he draws out, and gracefully bends the neck; he shapes the head, the beak, and the tail; then, with slender enamel rods of a proper color, he makes the eyes; he next opens up the beak with pointed scissors; he forms the wings and the lege; finally attaching the toes, the bird stands complete. The enameller also makes artificial eyes for human beings, imitating so perfectly the colors of the sound eye of any individual, as to render it diflicult to discover that he has a blind and a seeing one. It is difficult to make large articles at the blowpipe ; those which surpass 5 or 6 inches become nearly unmanageable by the most expert workmen. Enamelling of Cast Iron and other Hollow Ware for Saucepans, ^. Sulphate of Magnesia. EQUIVALENTS, CHEMICAL. {Stochiomdrie, Germ.) This expression was first employed by Dr. Wollaslon, to denote the primary proportions in which the various chemical bodies reciprocally combine; the numbers representing these proportion! being referred to one standard substance of general interest, such as oxygen or hydrogen reckoned unity, or 1,000. Dr. Dalton, who is the true author of the gra.nd discovery of definite and multiple chemical ratios, calls these equivalent numbers atomic weights, when reduced to their lowest terms, either hydrogen or oxygen being the radix of ihe scale. Though it belongs to a chemical work to discuss the principles and develop the applications of the Atomic Theory, I shall be careful, upon all proper occasions, to point out the vast advantages which the chemical manufacturer may derive from it, and to show how much he may economize and improve his actual processes by its means. See Element. ESSENCES are either ethereous oils, in which all the fragrance of vegetable products reside; or the same combined and diluted with alcohol. See Oils, Ethereous. ESSENCE D'ORIENT, the name of a pearly looking matter procured frona the Way or bleak, a fish of the genus cyprinus. This substance, which is found principally at the base of the scales, is used in the manufacture of artificial pearls. A large quan- tity of the scales being scraped into water in a tub, are there rubbed between the hands to separate the shining stuff', which subsides on repose. The first water being decanted, more is added with agitation till the essence is thoroughly washed from all impurities ; when the whole is thrown upon a sieve ; the substance passes through, but the scales are retained. The water being decanted off", the essence is procured in a viscid r*rMe, of a bluish white color, and a pearly aspect. The intestines of the same fish are also covered with this beautiful glistening matter. Several other fish yield it, but in smaller proportion. When well prepared, it presents exactly the appearance and reflections of the real pearls, or the finest mother of pearl ; properties which are probably owing to the interposition of some portions of this same substance, between the laminae of these shelly concretions. Its chemical nature has not been investigated ; it putrefies readily when kept moist, an accident which may, however, b** counteracted by water of ammo- nia. See Pearls. ETCHING Varnish. (Jetzgrund-Deckfimissy Germ.) Though the practice of thb elegant art does not come within the scope of our Dictionary, the preparation of the var- nishes, and of the biting menstrua which it employs, legitimately does. The varnish of Mr. Lawrence, an English artist resident in Paris, is made as follows: Take of virgin wax and asphaltum, each two ounces, of black pitch and burgundy-pitch each half an ounce. Melt the wax and pitch in a new earthenware glazed pot, and add to them, by degrees, the asphaltum, finely powdered. Let the whole boil till such time as that, taking a drop upon a plate, it will break when it is cold, on bending it double two or three times betwixt the fingers. The varnish, being then enough boiled, must be taken off" the fire, and after it cools a little, must be poured into warm water that it may work the more easily with the hands, so as to be formed into balls, which must be kneaded, and put into a piece of taflety for use. Care must be taken, first, that the fire be not too violent, for fear of burning the ingredients, a slight simmering being sufficient ; secondly, that whilst the asphaltum is putting in, and even after it is mixed with the mgredients, they should be stirred con- tinually with the spatula; and thirdly, that the water into which this composition is thrown should be nearly of the same degree of warmth with it, in order to prevent a kind of cracking that happens when the water is too cold. The varnish ought alwaj's to be made harder in summer than in winter, and it will become so i£ it be s\ifl'ered to boil longer, or if a greater proportion of the asphaltum or 1 654 ETHER. . 1 i n fctown rosin be used. The esperiraent above mentioned, of the drop snffered to cool, will determine the degree of hardness or softness that may be suitable to Oie season \ifii6Q it is uscu* Preparation of the hard varnish used by Callot, commonly called the Florence Var- nish :— Take four ounces of fat oil very clear, and made of good linseed oil, like that used by painters ; heat it in a clean pot of glazed earthenware, and afterwards put to it four ounces of mastick well powdered, and stir the mixture briskly till the whole be weU melted, then pass the mass through a piece of fine linen into a glass bottle with a long neck, that can be slopped very securely ; and keep it for the use that will be explained Method of applying the soft varnish to the plate, and of blackening it :— The plate being well polished and burnished, as also cleansed from all greasiness by chalk or Span- ish white, fix a hand-vice on the ed^e of the plate where no work is intended to be, to serve as a handle for managing it when waim'; then put it upon a chafing dish, in which there is a moderate fire, and cover the whole plate equally with a thin coat of the var- nish ; and whilst the plate is warm, and the varnish upon it in a fluid state, beat every part of the varnish gently with a small ball or dauber made of cotton tied up in taflety, which operation smooths and distributes the varnish equally over the plate. When the plate is thus uniformly and thinly covered with the varnish, it must be blackened by a piece of flambeau, or of a large candle which aflbrds a copious snxxke ; sometimes two or even four such candles are used together for the sake of despatch, vnat the varnish may noc grow cold, which if it does during the operation, the plate must be heated again, that it may be in a melted state when that operation is performed; but great care must be taken not to burn it, which, when it happens, may be easily perceived by the varnish appearing burnt, and losing its gloss. . The menstruum used and recommended by Turrell, an eminent London artist, lor etching upon steel, was prepared as follows : — Take Pyroligneous acid 4 parts by measure. Alcohol 1 part, mix, and add Nitric acid 1 part. This mixed liquor is to be applied from 1| to 15 minutes, according to the depth desired. The nitric acid was employed of the strength of 1-28— the double aquafortis of the shops. . . . i. V The eau forte or menstruum for copper, used by Callot, as also by Piranesi, with a slight modification, is prepared with 8 parts of strong French vinegar, 4 parts of verdigris, 4 ditto sea salt, 4 ditto sal ammoniac^ 1 ditto alum, 16 ditto water. The solid substances are to be well ground, dissolved in the vinegar, and diluted with the water ; the mixture is now to be boiled for a moment, and then set aside to cool. This menstruum is applied to the washed, dried, and varnished plate, after it has suf- fered the ordinary action of aquaf :rtis, in order to deepen and finish the delicate touches. It is at present called the eau forte a passer. ETHER is the name of a class of very light, volatile, inflammable, and fragrant spirituous liquids, obtained by distilling, in a glass retort, a mixture of alcohol with almost any strong acid. Every acid modifies the result, in a certain degree, whence several varieties of ether are produced. The only one of commercial importance is sulphuric ether, which was first made known under the name of sweet oil of vitriol, in 1540, by the receipt of Walterus Cordus. Froberus, 190 years after that date, directed the attention of chemists afresh to this substance, under the new denominalioa of efher. . *. ■ . j There are two methods of preparing it ; by the first, the whole quantity of acid and alcohol are mixed at once, and directly subjected to distillation ; by the second, the alco- hol is admitted, in a slender streamlet, into a body of acid previously mixed with a little alcohol, and heated to 220° Fahr. I. Mix equal weights of alcohol at spec. grav. 0'830, and sulphuric acid at 1-842, by introducing the former into a large tubulated retort, giving it a whirling motion, so that the alcohol may revolve round a central conical cavity. Into this species of whirl- pool the acid is to be slowly poured. The mixture, which becomes warm, is to be forthwith distilled by attaching a sp iclous receiver to the retort, and applying the heat of a sand-bath. The formation of ether takes place oMy at a certain temperature. If the contents of the retort be allowed to coo*, and be then slowly heated in a water-bath, •kohol alone will come over for some time without ether, till the mixture acquires Iht ETHER. 655 proper degree of heat. The first receiver should be a globe, with a tube pioceeding from its bottom, into » second receiver, of a cylindric shape, surrounded with ice-cold water. The joints must be well secured by lutes, after the expanded air has been allowed to escape. The liquid in the retort should be kept in a steady state of ebulli- tion. The ether, as long as it is produced, condenses in the balloon and neck of the receiver in striae ; when these disappear the process is completed. The retort must now be removed from the sand ; otherwise it would become filled with white fumes contain- ing sulphurous acid, and denser sirise would flow over, which would contaminate the light product with a liquid called sweet oil of wine. The theory of etherification demonstrates that when strong sulphuric acid is mixed with alcohol, there is formed, on the one hand, a more aqueous sulphuric acid, and, on the other, sulphovinic acid. When this mixture is made to boil, the sulphovinic acid is decomposed, its dihydrate of carbon combines with the alcohol, and constitutes ether; while the proportion of sulphovinic acid progressively diminishes. Mr. Hennell, of the Apothecaries' Hall, first explained these phenomena, and he was confirmed in his views by the interesting researches of Serullas. The acid left in the retort is usually of a black color, and may be employed to convert into ether half as much alcohol again j on experiment which may be repeated several times in succession. The most profitable way of manufacturing ether has been pointed out by Boullay. It consists in letting the alcohol drop in a slender stream into the acid, previously healed to the etherifyin^ temperature. If the acid in this case were concentrated to 1-846, the reaction would be too violent, and the ether would be transformed into bicarbureted hydrogen (dihydrate of carbon). It is therefore necessary to dilute the acid down to the density of 1'780 ; but this dilution may be preferably effected with alcohol, instead ol water, by mixing three parts of the strongest acid with 2 of alcohol, specific gravity 0-830, and distilling off a portion of the ether thereby generated ; after which ihe stream of alcohol is to be introduced into the tnbulure of the retort through a small olass lube plunged into the mixture; this tube being the prolongation of a metallic syphon, whose shorter leg dips into a bottle filled with the alcohol. The longer leg is furnished with a stop-cock, for regulating at pleasure the alcoholic streamlet. The distilled vapors should be transmitted through a worm of pure tin, surrounded by cold water, and the condensed fluid received in a glass bottle. The quantity of alcohol which can be thus converted into ether by a given weight of sulphuric acid, has not hitherto been accurately deter- mined ; but it is at least double. In operating in this way, neither sulphurous acid nor sweet oil of wine is generated, while the residuary liquid in the retort continues limpid and of a merely brownish yellow color. No sulphovinic acid is formed, and according to the experiments of Geiger, the proportion of ether approaches to what theory shows to be the maximum amount. In fact, 57 parts of alcohol of 083 sp. grav. being equiva- lent to 46-8 parts of anhydrous alcohol, yield, according to Geiger, 33§ parts of ether; and by calculation they should yield 37 J. The ether of the first distillation is never pure, but always contains a certain quantity of alcohol. The density of that product is usually 0-78, and if prepared by the first oi the above methods, contains, besides alcohol, pretty frequently sulphurous acid, and sweet oil of wine ; impurities from which it must be freed. Being agitated with its bulk of milk of lime, both the acid and the alcohol are removed at the same time • and if it be then decanted and agitated, first with its bulk of water, next decanted into a retort containing chloride of calcium in coarse powder, and distilled, one third of per- fectly pure ether may be drawn over. Gay Lussac recommends to agitate the ether first with twice its volume of water, to mix it, and leave it in contact with powdered unslaked lime for 12 or 14 hours, and then to distil off one third of pure ether. The remaining two thirds consist of ether containing a little alcohol. If in preparing eiher by Boullay's method, the alcohol be too rapidly introduced, much of this liquid will come over unchanged. If in this slate the ether be shaken with water, a notable quan- tity of it will be absorbed, because weak alcohol dissolves it very copiously. The above product should therefore be re-distilled, and the first half that comes over may be con- sidered as ether, and treated with water and lime. The other half must be exposeil afresh to the action of sulphuric acid. Pure ether possesses the following properties. It is limpid, of spec. grav. 0-713 or 0-715 at 60*; has a peculiar penetrating strong smell; a taste at first acrid, burnin«', sweetish, and finally cooling. It has neither an acid nor alkaline reaction ; is a non- conductor of electricity, and refracts light strongly. It is very volatile, boiling at 96" or 97 F., and produces by its evaporation a great degree of cold. At the tem- perature of 62-4, the vapor of ether balances a column of mercury 15 inches high, or half the weight of the atmosphere. When ether is cooled to —24** F. it begins' to crystallize in brilliant white plates, and at —47° it becomes a white crystalline solid. When vapor of ether is made to traverse a red hot porcelain lube, it deposites within it one half per cent, of charcoal, and there are condensed in the receiver one and two thirds 42 656 EVAPORATION. EVAPORATION. 657 ■V • pei cent, of a brown oil, partly in crystalline scales, and partly viscid. The crystalline portion is soluble in alcohol, but the viscid only in ether. The remainder of the decom- posed eiher consists of bi-carbureteJ hydrogen gas, tetrahydric carburet, carbonic oxyde gas, and one per cent, at most of gaseous carbonic acid. Ether takes lire readily, even at so^ae distance from a flame, and it should not there- fore be poured from one vessel to another in the neighborhood of a lighted candle. It raay be likewise set on fire by the electric spark. It burns all away with a bright fuligi- nous flame. When the vapor of ether is mixed with 10 times its volume of oxygen, it turns with a violent explosion, absorbs 6 times its bulk of oxygen, and produces 4 times its volume of carbonic acid gas. Ether alters gradually with contact of air; absorbing oxygen, and progressively chang- ing into acetic acid and water. This conversion lakes place very rapidly when the ether is boiled in an open vessel, while the acid enters into a new combination forming acetic ether. Ether should be preserved in bottles perfectly full and well corked, and kept in a cool place, otherwise it becomes sour, and is destroyed. In contains in this slate 15 per cent, of its bulk of azote, but no oxygen gas, as this has combined with its elements. Ether is composed of oxygen 21*24; hydrogen ]3*85; carbon 65*05. This composi- tion may be represented by 1 prime equivalent of water, and 4 primes of bi-carburetted hydrogen gas ; in other words, ether contains for 1 prime of water, once as much olefiant gas as alcohol, and its prime equivalent is therefore 468*15 to oxygen 100. By my ana- lysis, as published in the Phil. Trans, for 1822, ether is composed of oxygen 27*10; hy- drogen 13-3; and carbon 59-6 in 100 parts. The density of my ether was 0*700. One volume of vapor of ether consists of one volume of aqueous vapor and two volumes of olefiant gas (bi-carbureted hydrogen), while alcohol consists of two volumes of each. ETHER, ACETIC, is used to flavor silent corn spirits in making imitsrion brandy. It may be prepared by mixing 20 parts of acetate of lead, 10 parts of alcohol, and 11| of concentrated sulphuric acid; or 16 of the anhydrous acetate, 5 of the acid, and 4| of ab- solute alcohol ; distilling the mixture in a glass retort into a very cold receiver, agitating along with weak potash ley the liquor which comes over, decanting the supernatant ether, and rectifying it by re-distillation over magnesia and ground charcoal. Acetic ether is a colorless liquid of a fragrant smell and pungent taste, of spec. grav. 0-866 at 45" F., boiling at 166° F., burning with a yellowish flame, and disengaging fumes of acetic acid. It is soluble in 8 parts of water. Acetic ether may be economically made with 3 parts of acetate of potash, 3 of very strong alcohol, and 2 of the strongest sulphuric acid, distilled together. The first product must be re-distilled along with one fifth of its weight of sulphuric acid; as much ether will be obtained as there was alcohol employed. ETHIOPS is the absurd name given by the alchemists to certain black metallic prepar- ations. Martial eihiops was the black oxyde of iron ; mineral ethiops, the black sulphuret of mercury ; and ethiops per se, the black oxyde of mercury. EVAPORATION (Eng. and Fr. ; Abdampfen ; Mdunsten, Germ.) is the process by which any substance is converted into, and carried oflf in, vapor. Though ice, camphor, and many other solids evaporate readily in dry air, I shall consider, at present, merely the vaporization of water by heat artificially applied. The vapor of water is an elastic fluid, whose tension and density depend upon the temperature of the water with which it is in contact. Thus the vapor rising from water heated to 165° F. possesses an elastic force capable of supporting a column of mer- cury 10*8 high ; and its density is such that 80 cubic feet of such vapor contain one pound weight of water ; whereas 32| cubic feet of steam of the density corresponding to a tem- perature of 212° and a pressure of 30 inches of mercury, weigh one pound. When the temperature of the water is given, the elasticity and specific gravity of the vapor emitted by it may be found. Since the vapor rises from ihe water only in virtue of the elasticity due to its gaseous nature, it is obvious that no more can be produced, unless what is already incumbt'Ut up- on the liquid have its tension abated, or be withdrawn by some means. Suppose the temperature of the water to be midway between freezing and boiling, viz., 122° Fahr., as also that of the air in contact with it, to be the same but replete with moisture, so that its interstitial spaces are filled with vapor of corresponding elasticity and specific gra- vity with that given off by the water, it is certain that no fresh formation of vapor can take place in these circumstances. But the moment a portion of vapor is allowed to es cap«, or is drawn off by condensation to another vessel, an equivalent portion of vapor will be immediately exhaled from the water. The pressure of the air and of other vapors upon the surface of water in an open vessel, does not prevent evaporation of the liquid ; it merely retards its progress. Experience shows that the space filled with an elastic fluid, as air or other gaseous body, is capable of receiving as much aqueous vapor as if it were vacuous, only the repletion of that •pace with the vapor proceeds more slowly in the former predicament than in the lat. ter, but m both cases it arrives eventually at the same pitch. Dr. Dalton has very in- geniously proved, that the particles of aeriform bodies present no permanent ob^^tacle to the introduction of a gaseous atmosphere of another kind among them, but merely obstruct Its dirtusion momentarily, as if by a species of friction. Hence, exhalation at atmospheric temperatures is promoted by the mechanical diffusion of the vapors through the air with ventilating fans or chimney draughts ; though under brisk ebullition, the force of the steam readily overcomes that mechanical obstruction. The quantities of water evaporated under different temperatures in like times arc proportional to the elasticities of the steam corresponding to these temperatures' A vessel of boiling water exposmg a square foot of surface to the fire, evanorate«s 726 grams m the minute; the elasticity of the vapor is equivalent to 30 inches of mercury. To find the quantity that would be evaporated from the same surface per minute at a heat of 88° F. At this temperature the steam incumbent upon water is capable of sud- portmg 1*28 inch of mercury ; whence the rule of proportion is 30 : 1*28 * * 725 • 30*93 • showing that about 31 grains of water would be evaporated in the minute If the air contains already some aqueous vapor, as it commonly does, then the quantity of evaoora- tion will be proportional to the difference between "he elastic force of that vaoor and what rises from the water. *^ ' Suppose the air to be in the hygrometric state denoted by 0-38 of an inch of mercury then the aW formula will become : 30 : 1*28 - 0*38 : : 725 : 21*41 ; showing that noJ more than 2Ii grains would be evaporated per minute under these circumstances The elastic tension of the atmospheric vapor is readily ascertained by the 'old ex- periment of Le Roi, which consists infilling a glass cylinder (a narrow tumbler for example) with cool spring water, and noting its temperature at the instant it becomes so warm that dew ceases to be deposited upon it. This temperature is that which cocre- spends to the elastic tension of the atmospheric vapor. See Vapor Table of. Whenever the elasticity of the vapor, corresponding to the temperature of the water is greater than the atmospheric pressure, the evaporation will take place not only from Its surface, but from every point in its interior; the liquid particles throughout the mass assuming the gaseous form, as rapidly as they are actuated by the calodc which subverts the hydrostatic equilibrium among them, to constitute the phenomena of ebul- htion. This turbulent vaporization lakes place at any temperature, even down to the Ireezmg point, provided the pneumatic pressure be removed from the liquid bv the air pump, or any other means. Ebullition always accelerates evaporation, as it serva of the water ^"^"^"""^ particles not simply from the surface, but from the whole body The vapors exhaled from a liquid at any temperature, contain more heat than the fluid from which they spnng; and they cease lo form whenever the supply of heat into the liquid IS stopped. Any volume of water requires for its conversion into vapor ^« and a half times as much heat as is sufficient to heat it from the freezing to the boiUng emperalure. The hea , m the former case, seems to be absorbed, being inappreciable by the thermometer ; for steam is no hotter than the boiling water from which it rises. It has been therefore called latent heat; in contradistinction to that perceived by the touch and nieasured by the thermometer, which is called sensible heat. The quantity of he^ absorbed by one volume of water in its conversion into steam, is about 1000^ Fahr • It would be adequate to heat 1000 volumes of water, one degree of the same scale -w to rais r.ne volume of boihng water, confined in a non-conducting vessel, to 118(? Were tne vessel charged with water so heated, opened, it would be instantaneously emp! tied by vaporization, ?.nce the whole caloric equivalent to its constitution as steam i^ present. When, upon he other hand, steam is condensed by contact with cold Mih! stances, so much heat is set free as is capable of heatin«» five and n hair t.rv,^. •. • vT of water, from 32° to 212° F. If the supply of hea ?o a copper be JiifZ filT^^' and a half will be required to drive off it's'w'ater in steam,7ovL'd%n"w' w t^Ten iressure."^ ' "^ '"^ ^^ ^'^'''^ ^'^'^' ""^^^ ^^^ atmospheriS Equal weights of vapor of any temperature contain equal quantities of heat; for example, the vapor exhaled from one pound of water, at 77° F., absorbs during its formation and will g»7<,»t in its condensation, as much heat as the steam pro^luced by one pound of water at 212° F. The first portion of vapor with a tensioniso inch«J occupies a space of 27*31 cubic feet,* the second, with a tension of 0*92 inch, occupies « space of 890 cubic feet.* Suppose that these 890 volumes were to be compressed into 27*31 m a cylinder capable of confining the heat, the temperature of the tapor wouW rise from 77° to 212°, in virtue of the condensation, as air becomes .so hot by com • One pound ayoirdupoii of water contains 27-72 cubic inches ; one cubic inch of water forms 16«6 cubi. is * r«7%l ! SwlbKt: " " ""' ^"^^ ''^''"*' '^^^ ''*™ 2^-2* '^"''''^ ^«" «^"«^ •^™» : "'d ^n 658 EVAPORATIO]^. EVAPORATION. 659 press-ion in a syringe, as to ignite amadou. The latent heat of steam at 212? F. n 11800—180=1000; that of vapor, at 77°, is 1180—45=1135*'; so that, in fact, the lower the temperature at which the vapor is exhaled, the greater is its latent heat, as Joseph Black and James Watt long ago proved by experiments upon distillation and the steam engine. From the preceding researches it follows, that evaporation may be effected upon two different plans : — 1. Under the ordinary pressure of the atmosphere ; and that either, A, by external application of heat to boilers, with a, an open fire ; 6, steam ; c, hot liquid media, B, by evaporation with air; a, at the ordinary temperature of the atmosphere; b, by currents of warm air. 2. Under progressively lower degrees of pressure than the atmospheric, down to evaporation in as perfect a vacuum as can be made. It is generally affirmed, that a thick metallic boiler obstructs the passage of the heat throush it so much more than a thin one, as to make a considerable difference in their relative powers of evaporating liquids. Many years ago, I made a series of experiments upon this subject. Two cylindrical copper pans, of equal dimensions, were provided ; but the metal of the one was twelve times thicker than that of the other. Each being charged with an equal volume of water, and placed either upon the same hot plate of iron, or immersed, to a certain depth, in a hot solution of muriate of lime, I found that the ebullition was greatly more vigorous in the thick than in the thin vessel, which I ascribed to the conducting substance up the sides, above the contact of the source of heat, being 12 times greater in the former case than in the latter. If the bottom of a pan, and the portions of the sides, immersed in a hot fluid medium, solution of caustic potash or muriate of lime, for example, be corrugated, so as to contain a double expanse of metallic surface, that pan will evaporate exactly double the quantity of water, in a given time, which a like pan, with smooth bottom and sides, will do immersed equally deep in the same bath. If the corrugations contain three times the quantity of metallic surface, the evaporation will be threefold in the above circum- stances. But if the pan, with the same corrugated bottom and sides, be set over a fire, or in an oblong flue, so that the current of flame may sweep along the corrugations, it will evaporate no more water from its interior than a smooth pan of like shape and dimensions placed alongside in the same flue, or over the same fire. This curious fact I have verified upon models constructed with many modifications. Among others, I caused a cylindrical pan, 10 inches diameter, and 6 inches deep, to be made of tin- plate, with a vertical plate soldered across its diameter; dividing it into two equal semi-cylindrical compartments. One of these was smooth at the bottom, the other corrugated ; the former afforded as rapid an evaporation over the naked fire as the latter^ but it was far outstripped by its neighbor when plunged into the heated liquid medium. If a shallow pan of extensive surface be heated by a subjacent fire, by a liquid medium or a series of steam pipes upon its bottom ; it will give off less vapor in the same time when it is left open, than when partially covered. In the former case, the cool in- cumbent air precipitates by condensation a portion of the steam, and also opposes considerable mechanical resistance to the diffusion of the vaporous particles. In the latter case, as the steam issues with concentrated force and velocity from the contracted orifice, the air must offer less proportional resistance, upon the known hydrostatic principle of the pressure being as the areas of the respective bases, in communicating vessels. In evaporating by surfaces heated with ordinary steam, it must be borne in mind that a surface of 10 square feet will evaporate fully one pound of water per minute, or 725X 10 = 7250 gr., the same as over a naked fire; consequently the condensing sur- face must be equally extensive. Suppose that the vessel is to receive of water 2500 lbs., which corresponds to a boiler 5 feet long, 4 broad, and 2 deep, being 40 cubic feet by measure, and let there be laid over the bottom of this vessel 8 connected tubes each 5 inches in diameter and 5 feet long, possessing therefore a surface of 5 feet square. If charged with steam, they will cause the evaporation of half a pound of water per minute. The boiler to supply the steam for this purpose must expose a surface of 5 square feet to the fire. It has been proved experimentally that 10 square feet surface of thin copper can condense 3 lbs. of steam per minute, with a difference of temperature of 90 degrees Fahr. In the above example, 10 square feet evaporate 1 lb. of watei per minute; the temperature of the evaporating fluid being 212° F., consequently 3:1 : : 90 :'^. During this evaporation the difference of the temperature is there- fore = 30°. Consequently the heat of the steam placed in connexion with the inte- rior of the boiler, to produce the calculated evaporation, should be, 212 -|- 30 = 242?, corresponding to an elastic force of 536 inches of mercury. Were the temperature oi the steam only 224, the same boiler in the same time would produce a diminished qiit» tity of steam, in the proportion of 12 to 30 ; or to produce the same quantity the boiler oi tubular surface should be enlarged in the profK)rtion of 30 to 12. In general, however steam boilers employed for this mode of evaporation are of such capacity as 'to give «• unfailing supply of steam. I shall now illustrate by some peculiar forms of apparatus, different systems of cv». poration. Fig, 496 explains the principles of evaporating in vacuo, a b represe&H ! ^1 ^ .^'f '^^"''^^*^ "^'^^ ^^^ ^'^"^^ *^ ^^ evaporated. The somewhat wide oriiico tw« t, " '^u^*^^T"P'"^'^^'"^^^ to admit the hand for the purpose of cleaning it it^Z I f out when the operation is finished ; h is the pipe of communication with the K^Z fu' * '^ * ^".^^ prolonged and then bent down with its end plunged into the liquor to be evaporated, contained in the charging back, (not shown in the figure), h is IS r,l ^^^"'^""'cating with the vacuum pan at the top and bottom, to show by the fteight of the column the quantity of liquid within. The eduction evaporating pipe c »s provided with a stop-cock to cut off the communication when required, t is a tube lor the discharge of the air and the water from the steam-case or jacket; the refrigerator fiil .K ^"'■'"^'^ °^ ^^'" "PPP^^ Jy^s about 1 inch in diameter, arranged zig-zag or spirally ike the worm of a st.ll in a cylinder. The small air-tight condenser f, connected with the efflux pipe /of the refrigerator, is furnished below with ft discharge cock ?, and surrounded by a coolmg case, for the collection of the water condensed by the refri-er w!!h fi, '/' "Pf M P^' ^5^? '' V"^« *^' ^'^*^ furnished with a cock, which communicates with the steam boiler, and through which the pan a d is heated. The operation of this apparatus is as follows: after opening the cocks c f e and before admitting the cold water into the condenser e, the cock of the pipe fc ii opened, m order that by injecting steam it may expel the included air; after which the and th^ '"t f "'' '^ ''i''"'- IK ""'T ""^' "°^ ^' '"^^^"^^d into the condense" ?hl oK T . k"''^^ '7*'T°" J^^ ^T'^ ^"^ ^^ evaporated rises from the charging back through the tube 6, and replenishes the vacuum pan to the proper height, as shown bv the register glass tube h. Whenever the desired evaporation or concentr'aSon is effect! fi,:n f. *^°*^^ c ""^t^e closed, the pipe k opened, so as to fill the pan with steam, and then the efflux cock a is opened to discharge the residuary liquor. By shutting the ,h. n'nf ^r ' ^"'^^^^n^"^"? Ihe cock 6, the pan will charge itself afresh with liquor, and the operation will be begun anew, after b has been shut and c opened. The contents of the close water cistern f, may be drawn off during each operation. For this purpose, the cock /must first be shut, the cold water is to be then run out of the condenser g, and A: and g are to be opened. The steam entering by k makes the water flow, but whenever the steam itself issues from the cock g, this orifice must be immediately shut, the cock / opened, and the cold water again introduced, whereupon the condensed water that had meanwhile collected in the under part of the refrigerator Bows off into the condenser vessel r. Since some air always enters with the liquoj i 1 1 660 EVAPORATION. gneked into the pan, it most be removed at the time of drawing oflf the water from the two condensers, by driving steam through the apparatus. This necessity will be less argent if the liquor be made to boil before being Introduced into the vacuum pan. Such an apparatus may be modified in size and arrangement to suit the peculiar object in view, when it will be perfectly adapted for the concentration of extracts of every kind, as well as saline solutions containing vegetable acids or alkalis. The interior vessel of A B should be made of tinned or plated copper. For an account of Howard's vacuum pan, made upon the same principle, see Sugar. When a boiler is set over a fire, its bottom should not be placed too near the grate, lest it refrigerate the flame, and prevent that vivid combustion of the fuel essential to the maximum production of heat by its means. The evil influence of leaving too little room between the grate and the copper may be illustrated by a very simple experiment. If a small copper or porcelain capsule containing water be held over the flame of a candle a little way above its apex, the flame will sufler no abatement of brightness or size, but will continue to keep the water briskly boiling. If the capsule be now lowered into the middle of the flame, this will immediately lose its brightness, becoming dull and smoky, covering the bottom of the capsule with soot; and cwing to the imperfect combustion, though the water is now surrounded by the flame, its ebullition will cease. Fig. 497 is a section of two evaporating coppers en suilBf so mounted as to favor the Djuiuiiiiiiiiiiiiiiiiiijjiiiiuuinniui' "'.1.. '.'T?f j.l'. '..\ a b full combustion of the fuel, a is the hearth, in which wood or coal may be burned. For coal, the grate should be set higher and be somewhat smaller, a is the door for feeding the fire; rf, an arch of fire-bricks over the hearth ; c, a grate through which the ashes fall into the pit beneath, capable of being closed in front to any extent by a sliding door b, B and c are two coppers incased in brickwork ; / the flue. At the end of the hearth near m, where the fire plays first upon the copper, the sole is made somewhat lower and wider, to promote the spreading of the flame under the vessel. The second copper, c, receives the benefit of the waste heat ; it may be placed upon a higher level, so as to discharge its concentrated liquor by a slop-cock or syphon into the first. When coals are burned for heating such boilers, the grate should be constructed as shown in the figure of the brewing copper, page 122. Fig. 498 represents a pan for evaporating liquids, which are apt, during concentra- tion, to let fall crystals or other sediment. These would be injured either by the fire play ing upon the bottom of the pan, or, by adhesion to it, they would allow the metal to get red hot, and in that state run every risk of being burnt or rent on the sudden intrusion of a little liquor through the incrustation. When large coppers have their bottoms planted in loam, so that the flame circulates in flues round their sides, they are said to be cold-set. A is a pear-shaped pan, charged with the liquid to be evaporated ; it is furnished with a dome cover, in which there is an opening with a flange /, for attaching a tube, to conduct the steam wherever it may be required, a is the fire-place ; b the ash-pit. The conical part ter- minates below in the tube g, furnished with a stop-cock at its nozzle h. Through the tube c d c', furnished above and below with the stop- cocks c and c', the liquid is run from the EXPANSION. 661 charging back or reservoir. During the operation, the upper cock c is kept partially open, to replace the fluid as it evaporates ; but the under cock c' is shut. The flame from the fire-place plays round the kettle in the space «, and the smoke escapes down- wards through the flue t into the chimney. The lower cylindrical part g remains thus comparatively cool, and collects the crystalline or other solid matter. After some time, the under stop-cock c', upon the supply-pipe, is to be opened to admit some of the coW liquor into the cylindrical neck. That cock being again shut, the sediment settled, and the large stop cock (a horizontal slide-valve would be preferable) h opened, the crystals are suffered to descend into the subjacent receiver; after which the stop-cock h is shut, and the operation is continued. A construction upon this principle is well adapted for heating dyeing coppers, in which the sediment should not be disturbed, or exposed to the action of the fire. The fire-place should be built as for the brewing copper. Fig. 499 represents aa 499 oblong evaporating pan, in which the flame, aAer beating along its bottom, turns up at its further end, plays back along Uf surface, and passes off in* to the chimney, a is a rectangular vessel, from 10 to 15 feet long, 4 to 6 r t A T«u c 1- . . ^^^^ broad, and 1 or 1* leet deep. The fire-bricks, upon which the pan rests, are so arranged as to distribute the name equably along its bottom. For the following scheme of generating, purifying, and condensing steam, Mr. Charles Clarke merchant, London, obtained a patent in January, 1843. His apparatus for XTrfr^no ^"^^-^'Vk ""^ economically into good fresh water, is represented in figs. BOO, 501 602. A IS the supply cistern, which communicates with a pipe a, with a self-regulating eduction apparatus n. c is a strong wrought iron cylinder, fitted at fhlrVn H *>rT ""g-pl'^cec, and covered with a conical top; it is about two thirds filled with the water to be operated upon, d is a cylindrical' furnace concentric with the water cylinder c; rf is an upward air and watertight tube, which serves both ZihtiT^' ^T^^' ^/^'"'^ i^" l""^^ '' ^"PP"^^ *« the furnace^ and as a passage for the escape of the smoke and other gaseous products of combustion; e is a hinged trap-door through which the fuel is passed into the tube d: h is a chimney into which the pipe d terminates: and e, a damper, by which the degree of activity given to the furnace can be regulated at pleasure; /is an open air-pipe, which l/ads from he outs.de, through the boiler into the furnace, a kittle way above the fire-bar^ and nssista in securing a good draught through the furnace iito the chimney. To the water cylinder o there are attached gauge-cocks, g g, for ascertaining from time to time the height of the water; / is a cock or tap fo? drawing off the brine, and^the? residual matters which collect at tire bottom of 'the boiler; fn is a screw cap and hole through which access may be had to the interior of the water cylinder g. when ii needs to be cleaned; e is a short pipe fitted into the conical top of the water cylinder <; which conveys the steam generated in it into the steam-head or receiver f- o is a TZ^ll 5 k ''*^'"^- "P^" ^*^«,^P «f the pipe E, a little larger than that pipe, and kept steady by a weight, k of one or more pounds, suspended from it W wires. This plate prevents, m a great measure, the escape-water escaping into the steam-head (an accident commonly called prtming m steam engines); becaufe, till the steam has acquired a pressure exceeding that of the counterweight h it cannot raise the weight o^^ so as to escape freely into the steam-head f, since any particle of water must, during the ns.ng of the cap g. strike against it. and drop back, either into the water iylindef hi^T^ ^ P'^. *^ ''' 'l^ ^^t jPa^e round that pipe at the bottom of the steam- head h; whence it may be withdrawn by the cock shown in the drawing, h is a pipe which conveys the steam from the steam-head f to the rectifier a. This consists simply of a cylinder about one third the size of the cylinder c) laid horizontally, in l«l i^i f P^'i "^'"'''Z \^^ ^^ ;^*J'' 'P"^^"^ «<>"«<^^ *n, the end of the discharged tubett is inserted; and at a little distance from this tube there are air apertures, a, a, furnished with shutters in the inside, slanting from the top downward, to prevent as much as possible the escape outward of any vapor which may occasionally be carried down with the water from the con- denser. The middle compartment, y2, is perforated, convex at top, and concave at bottom ; so that the water that drops from the tube «, in the convex top of y2, falls off laterally through small pipes into the chamber y% while its concave bottom turns the water into a central filtering-box, c, that projects a little into y3, set to receive it. For aerating this water, the bottom of yz is covered about an inch deep with small pebbles. y3, which is the reservoir of the purified cool water, is perforated with small holes, c', ci, are small pipes for promoting a continual upward flow of cold air. y» is furnished with a tap to draw off its water, as required. For redistilling or rectifying spirituous liquids, the apparatus, ^g. 501 , is employed ; m which the supply cistern A is much larger, and close at top ; the upper condensing chambers, <', i% are also larger, but the lowest, ft, is narrowed. The second rectifier of^. 500, is removed. The feints collect in the bottom of the rectifier R, to be drawn off by a cock ; while the rectified spirit passes off at top into the condenser. The refri- gerator has only two compartments, and no pebbles. F is a funnel into which the spirits may be returned for redistillation. For extracting the soluble matter of vegetable infusions, the apparatus, shown in fig. 502,i3 used. The rectifier is vertical, has a screw-capped hand-hold, /, for admitting th€ vegetables, g is a steam-pipe ; and A is a funnel for returning portions of the liquid extract. R is connected by a pipe, fe, with the condenser, T, made in two por- tions, fitted water-tight together, but separable for the purpose of cleansing. The steam which passes from the boiler into the rectifier r disengages the soluble portion of the vegetable substances, and if they be volatile, carries them off to the condenser; if not, it combines and falls with them to the bottom of the vessel, whence this portion of the extract is drawn off by the cock, and a fresh charge may be introduced. The steam is shut off from the rectifier r by a cock on pipe g. When the steam is after- ward admitted to assist the process of maceration, the supply of it is regulated by th« stop-cocks in the pipes g and k. — Newton\t Journal, xxiii. p. 247, C. S. In each experiment 1,840 lbs. weight were burnt, and the relative quantities of water evaporated show the relative economic effect Two kinds of coal were used : Knowles'a Clifton coal, a free burning kind which does not cake, and produces a considerable quantity of ashes ; Barker and Evan's Oldham coal, a slow burning rich caking coal, yielding little ashes. The boiler was a 24-hor8e power, of Wait's waggon shape. Mr. IT. HouldswortKs Economy of Evaporation. Eflect per Minute. Water evapo rated by Average Tempe- Eco- Wei^Ut of Cbaije. Air. Coals Water 1.840 1 b. of rature in the first nomic Eflect % burnt. etapo- rated. lbs. of CoaL CoaL Flue. 1 Clifton coal: Lht. GalU. GaJU. Lbt. Dcgreet. 460 Ihs. No air - 4-64 2-5 992 5-41 973 106 bs Q 460 1bfl. 45 square Inches constant s aperture ... 4-68 3-21 1263 G-85 1165 135 230 lbs. Air regulated partly by the eye, and partly by a scale, varying in some degree with •if o the action of combustion • 443 809 1280 694 1122 136 ^ 230 lbs. 45 square inches 4-65 305 1210 6^ 1220 129 >k 230 lbs. No air - 4-43 2-3 942 512 995 100 "a 460 lbs. Air through two pipes 6 in. in diameter, each regulated by light - - - 4-65 SIS 1250 6-8 1160 134 i Oldham coal : 230 ll)«. No air - S«7 2-65 1S40 7-3 690 100 E .3 230 \\M. 35 square inches constant aperture 405 2-76 1260 6-85 1080 94 230 Iba 24 square inches constant a aperture ... 382 2-82 1360 7-4 1050 102 460 & 230 Ibe. Air regulated by s scale 3-84 2.94 1410 7.7 1070 106 Ad 230 lbs. Air regulated so as to pro- 1^ duce no smoke 361 2-87 1530 83 lav) 114 N Uald Oldham, 1 half Clifton- .... AM 29 1320 7-2 1060 664 EXPANSION. EXPANSION. 665 h ! ' I il I II 85 per cent 34 „ 4 » The average heat given in the first flue, as ascertained by a pyrometer and deduced from pyrometric diagrams. The air was admitted partly at the door and partly at the bridge ; at the latter point through one of Mr. Williams's diffusion boxes, except in the last experiment with Clifton coal. They showed the effect of admitting air in greater or less quantity permanently or periodically by a uniform or varying aperture ; and the general result arrived at is, that by the simple and inexpensive plan of admitting air into the furnaces at both the door and bridge by permanent apertures always open, varying in aggregate area from 1^ to 3 square inches (according to the quality of the coals) for every square foot of area of grate, an important saving in fuel is effected, an^ ^9_ of the dense smoke prevented, without any special care of the fireman. Deductions from the experiments on Clifton Coal: Gain in evaporation by regulated admission of air I)o. by 45 square inches constant aperture Do. by charges of 460 lbs. instead of 230 lbs. Steam produced in a given time : — ^o air - . 230 lbs. charges No air - - 460 lbs. do. 53 square inches air - 230 lbs. do. Air regulated - - 230 lbs. do. 63 square inches - 460 Iba do. showing that the admission of air increases the production of steam in a given time from 30 to 40 per cent EUDIOAIKTER, is the name of any apparatus subservient to the chemical examina* tion of the atmospheric air. It means a measure of purity, but it is employed merely to determine the proportion of oxygen which it may contain. The explosive eudiometer, ia which about two measures of hydrogen are introduced into a graduated glass tube, con- taining five measures of atmospheric air, and an electric spark is passed across the mix- ture, is the best of all eudiometers ; and of these the syphon form, proposed by me in a paper published by the Royal Society of Edinburgh in 1819, is probably the surest and most convenient. Volta's explosive eudiometer, as made in Paris, costs 3 guineas ; min« may be had nicely graduated for 6 or 8 shillings. EXPANSION (Eng. and Fr. ; Ausdehnung^ Germ.) is the increase of bulk experienced by all bodies when heated, unless a change of chemical texture takes place, as in tha case of clays in the potter's kiln. Table i. exhibits the linear expansion of several solida by an increase of temperature from 32^ to 212** Fahr. ; Table II. exhibits the expansion in bulk of certain liquids. TABLE l.^Linear Dilatation of Solids by Heat, Dimensions which a bar takes at 212°, whose length at 32? is 1-000000. 100 109 132 134 140 Dilatation Dilatation Substances Authority. in in Vulgar Decimals. Fractions. Glass tube - - - - - Smeaton 1-00083333 do. - ... - Roy - . - 1-00077615 do. • - . . . Deluc's mean - 1-00082800 niB do. .... . do. ..... Dulong and Petit Lavoisier and Laplace 1-00086130 1-00081166 TTTl Plate glass - - - . do. do. 1-000890890 ll^J do. crown glass ... do. do. 1-00087572 Ti4iy do. do. ... do. do. 1-00089760 IT XT do. do. ... do. do. 1-00091751 10^ do. rod - . - , Roy 1-00080787 Deal Roy, as glass 1 Platina Borda - - - 1-00085655 do. ..... Dulong and Petit 1-00088420 1 TT3T do. .... . Troughton 1 00099 180 do. and glass .... Berthoud . 1-00110000 Palladium .... Wollaston 1-00100000 Antimony . . - - - Smeaton 1-00108300 Cast-iron prism ... Roy . . - 1-00110940 Cast-iron ..... Lavoisier, by Dr Young: 1-00111111 Steel Troughton 100118990 Substances. do. at a higher heat Steel rod ... Blistered Steel - do. Steel not tempered do. do. do. tempered yellow . do. do. do. do. do. Steel - Hard Steel Annealed steel .... Tempered steel - . - - Iron --...- do. ..... . Soft iron, forged - . . - Round iron, wire drawn Iron wire - - . . - Iron - . . . ... Bismuth ..... Annealed gold .... Gold do. procured by parting - do. Paris standard, unannealed - do. do. annealed Copper - . _ _ . do. ..... do. ..... do. ..... do. - . - . _ Brass ..... do. - - . . _ do. ..... Brass scale, supposed from Hamburg Cast brass - - - . . English plate-brass, in rod . do. do. Brass - Brass wire - Brass - Copper 8, tin 1 Silver . do. . do. . do. do. Silver Brass 16, tin 1 - Speculum metal . • . Spelter solder; brass 2, zinc 1 Malacca tin .... Tin from Falmouth ... Fine pewter .... Grain tin - ... . Tin Soft solder ; lead 2, tin 1 - Zinc 8, tin 1, a little hammered . Lead ...... do. -.--.. Zinc --..-. Zinc, hammered out ^ inch per foot Glass, from 32° to 212'' do. from 212° to 392° . do. from 392° to 572° - in a trough form of cupel . Paris standard Authority. Roy Phil. Trans. 1795, 428 Smeaton ... Lavoisier and Laplace do. do. do. do. do. do. do. do. Troughton Smeaton - . - Muschenbroek do. Borda ... Smeaton ... Lavoisier and Laplace do. do. Troughton Dulong and Petit Smeaton ... Muschenbroek EUicot, by comparison Lavoisier and Laplace do. do. do. do. Muschenbroek Lavoisier and Laplace do. do. Troughton Dulong and Petit Borda ... Lavoisier and Laplace do. do. Roy Smeaton ... Roy ... do. ... Troughton Smeaton ... Muschenbroek Smeaton ... Herbert - . _ EUicot, by comparison Muschenbroek Lavoisier and Laplace do. do. Troughton Smeaton ... do. ... do. - Lavoisier and Laplace do. do. Smeaton ... do. - Muschenbroek Smeaton ... do. . Lavoisier and Laplace Smeaton . . - do. - do. Dulons do. do. and Petit do. do. Diiatatiuu in Decimals. 1-00114470 1-00112500 1-00115000 1-00107875 1-00107956 1-00136900 100138600 1-00123956 1-00118980 1-00122500 1-00122000 1-00137000 1-00115600 J -00125800 1-00122045 1-00123504 1-00144010 1-00118203 1-00139200 1-00146000 1-00150000 1-00146606 1-00155155 1-00151361 10019100 100172244 1-00171222 1-00191880 1-00171821 1-00178300 1-00186871 1-00188971 1-00185540 1-00187500 1 00189280 1-00189490 1-00191880 1-00193000 1-00216000 1-00181700 1-00189000 1-0021000 1-00212000 1-00190974 1-00190868 1-00-20826 1-00190800 1-00193300 1-00205800 1-00193765 1-00217298 1-00228300 1-00248300 1-00284000 1-00250800 1-00269200 1-00284836 1-00286700 1 00294200 1-00301100 1-00086130 1-00091827 1-000101114 The last two measurements by an air thermometer. Dilatation in Vulvar Fractions. 92B jJt ffi« 1 6T5 1 _1 SJ2 1 S^4 1 1 JIT 1 ITeT losd i« IN 666 EXTRACTS. TABLE n. Expansion of certain Liquids by being Heated from 32? hilo8ophical painstaking with mechanical skill and ingenuity, such as is not often witnessed ; he finally settled the form which it was best to give to the tube, and ai-ranged the whole of the executive details; he personally superintended the construction of the Conway Bridge, which our readers are aware is but the Menai or Britannia Bridge on a smaller scale; and he only retired from further co-operation with Mr. Stephenson in the affair, when nothing new was left to be discovered or achieved. The motives for his retirement are thus very fairly and temperately stated : — " 1 1 have now brought down this correspondence to the period when my oflScial con- nection with the Chester and Holyhead Railway Company as engineer, for the con- struction of the tubular bridges, may be said to have virtually ceased, and I should willingly have passed over in silence the remainder of the events which transpired, were it not that the completeness of the narrative, as well as the justification of my conduct, demanded some explanation, independently of the regret which I experienced in with- drawing from an undertaking to which I had devoted so much time and thought^ — an FAIRBAIRN'S TUBULAR BRIDGES. 669 undertaking fraught with the greatest interest, and which had, as it were, grown up in all its magnificent proportions under my own directions. I can truly say that the dis- agreement which took place with Mr. Stephenson is on my part much deplored. But I trust that the reader of the foregoing pages will at least have arrived at the conclusion, that I had taken the most important part in developing, and giving a practical form to Mr. Stephenson's idea, and also in the superintending the construction and erectioQ of the first Conway tube. The fact is, I labored almost incessantly in devising plans, or in watching over the practical details of the work, from the day in which Mr. Stephenson's suggestion was communicated to me until the close of my engagement; and I can sincerely say that I was always actuated by the principle of leaving nothing undone which could in any way contribute to the successful accomplishment of the undertaking. Regardless of the prognostications of failure with which the scheme was assailed, and in despite of the opposition of those whose assistance I had solicited, I uniformly advocated the peculiar principle on which the Conway Bridge has been con- structed. • " *Such being my position, and viewing the extent of services I had rendered, it will, I think, be generally allowed that it was very natural that I should desire to have my name publicly associ^ited with Mr. Stephenson's as joint engineer for these bridges. Indeed, it may very fairly be said that I might have ventured to claim this distinction, since it had been conferred upon me by the Board of Directors on Mr. Stephenson's own recommendation. If, instead of success having crowned our efforts, failure had im- fortunately ensued, would not my reputation have suffered as well as Mr. Stephenson's? The working plans having gone forth with my name alone attached to them, and from my being recognised as the acting engineer, might not the whole blame have been con- veniently thrown on me in case of failure? " *It was not, however, on any of these grounds that I was induced to resign mv appointment, for there had not then occurred any opportunity where I conceived it necessary to have my position publicly recognised ; and I had always believed that, when the proper time came, Mr. Stephenson would be the first to establish that position, and acknowledge the services I had rendered. The recognition was, however, very shortly afterwards denied me. The first Conway tube having been completed, and the success of the principle established, I conceived that the construction of the remaining tubes simply required a close attention to the system of construction already adopted, and therefore might safely be entrusted to those gentlemen whose constant presence during the building of the first tube had rendered them thoroughly acquainted with the whole details of the work. By such an arrangement, moreover, the Company would save the amount which had hitherto been paid for my services, and I should be enabled to devote my time to other pursuits which I had neglected for this work, and which now urgently demanded my attention. This was one reason for my retirement ; but what chiefly led me to this decision, was the position assumed by Mr. Stephenson, his public misrepresentation of the position I held under the Company, and his endeavor to recognise my services as the labors of an assistant under his control, and acting entirely under his direction. Had Mr. Stephenson in his public address done me the justice to state my independent claim to some of the most important principles observed in the construction of the tubes, I might, perhaps, have continued my services until the final completion of the whole undertaking; and, most assuredly, this work would never have come before the public. I now appeal to the preceding pages of this narrative, whether Mr. Stephenson's assertions are borne out by the simple statement of facts? I have overstated nothing, concealed nothing; and the reader is left to draw his own conclusions from these facts, after having become acquainted with the course pursued by Mr. Stephenson, which I will in conclusion concisely relate.' (p. 111.) " Mr. Fairbairn proceeds then to give an account of a public dinner to celebrate the completion of the Conway Bridge, which took place on the 17th of May, 1848; on which occasion it was, Mr. Stephenson first openly assumed that position in regard to Mr. Fairbairn and the undertaking, which has made the present appeal to public justice necessary. Mr. Stephenson's speech was confessedly a studied affair— he had announced beforehand that he would avail himself of the opportunity of 'setting the question at rest;* but for all that it does not take Mr. Fairbairn many words to demolish it utterly. • ♦ The inaccuracies, both as to facts and dates, in the statements of Mr. Stephenson, are very numerous. It simply requires a reference to the short description of the Ware Bridge, and to the drawings, to disprove the assertion, that it is a thin tubular bridge, although not precisely the same as the present, yet in principle precisely the same ; and it can easily be shown too, that considering the Ware Bridge as a simple girder bridge, it is exceedingly defective in design. Is there anything new in this ap- plication of wrought-iron plate girders? As well might it be said that the combinatioQ 670 FAIRBAIRN'S TUBULAR BRIDGES. of wroiight-iron deck beams, 8o many years applied in iron ships for the support of the decks, is a " counterpart of the proposed cellular top for the Britannia tubes." I really caoDot but regret that Mr, Stephenson, whose name will be always associated with the grandest bridge that has ever been constructed, should have committed himself in making such an erroneous assertion as that it was by reviving and extending his original conception of this imperfect structure at Ware, that he was led to originate the bridges crossing the Conway and Menai Straits. "*Mr. Stephenson's remarks further admit of the disingenuous construction that his scheme was matured before the Bill for the Chester and Holyhead Railway was passed by Parliament, and before I was consulted, and that he was at that early period ac- quainted with the present design of the bridge. He refers to the incredulous glances which were directed towards him when the description of the bridge was explained to the Committee ; and intimates, " that it was not until the Bill had been obtained, and it became necessary to commence, that he requested my assistance." Now, my advice was asked by Mr. Stephenson before his evidence to the Parliamentary Committee was given, and he announced his idea to that Committee strengthened by more than one opinion of its feasibility. Let the reader turn again to the earlier letters of the correspondence, and he will find of what a crude and dangerous scheme that idea consisted ; how totally dissimilar in form and principle it was to the present tubular structures, and how slowly Mr. Stephenson was persuaded to give up his earliest conceptions. Again ; Mr. Stephenson states that he called in the aid of Mr. Hodgkinson and myself at the same time; now it is essential to the proof of my claims that this assertion should be explicitly contradicted. It was I, and not Mr. Stephenson, who solicited Mr. Hodg- kinson's co-operation, and this was not done until I had been actively engaged for several months in my experimental researches, and after I had discovered the principle of strength which was offered in the cellular top, and not only proved the impractica- bility of Mr. Stephenson's original conception, but had given the outline of that form of tube which was ultimately carried into execution. "'When Mr. Stephenson had made up his mind to claim in the manner he did the whole merit of the undertaking, it is noti difficult to understand his reason for giving Mr. Clarke, his own assistant, so prominent a position. I willingly bear my testimony to the great value of the services rendered by Mr. Clarke, to his talents, and to the great energy which he displayed in working out his several duties, but these had no reference whatever to the designing of the structures.' (p. 178.) " There is one part of the case on which we think Mr. Fairbairn does not insist enough, thougli, in our judgment, it is of itself decisive of the inordinateness of Mr. Stephenson's pretensions. Mr. Stephenson and his friends, for obvious reasons, slur it over alto- gether. We refer to Mr. Fairbairn's appointment to be joint engineer along with Mr. Stephenson to the Conway and Britannia Bridges. The evidence of this is a Minute of the Board of Directors of the Chester and Holyhead Railway, dated 13th May, 1846, which we here quote at length from the work before us. "'Resolved — Ist That Mr. Fairbairn be appointed to superintend the construction and erection of the Conway and Britannia Bridges, in conjunction with Mr. Stephenson. "'2d. That Mr. Fairbairn have, with Mr. Stephenson, the appointment of such persons as are necessary, subject to the powers of their dismissal by the Directors. "'3d. That Mr. Fairbairn furnish a list of the persons he requires, with the salaries he proposes for all foremen or others above the class of workmen. "'4th. That advances of money be made on Mr. Fairbairn's requisition and certi- ficates, which, with the accounts, or vouchers, are to be furnished monthly. " '5th. That the Directors appoint a bookkeeper at each spot, the Conway and the Menai.' "To talk, after this, of Mr. Fairbairn's being only entitled to a secondary and subor- dinate place in the affair, is to outrage all truth and propriety. " We can but regard with profound pity the hallucination which has betrayed a man of Mr. Stephenson's genius and worth (this unfortunate episode notwithstanding) into so false a position. " We do not overlook that we have as yet Mr. Fairbairn's statement of the case only, and that we may expect to see, ere long, sometliing of a very opposite complexion from Mr Stephenson or some of his friends. We shall give all due consideration to any such counter-statement when it comes before us; but so well is all Mr. Fairbairn says borne out by written, and therefore unalterable proofs, that we do not, in the meanwhile, hesitate to avow our firm belief that nothing which can possibly be adduced in the way of either evidence or argument, can ever alter materially the conclusion at which we have already arrived." — Mechanic's Magazine.) Fairbairn's Tubular Girder Bridges. — William Fairbairn, Esq., of Manchester, F. R. S., and Member of the Institute of France, has been long recognised as the most accomplished of our factory engineers and the most skilful of our millwrights, by his FAIRBAIRN'S TUBULAR BRIDGES. 671 admirable fire-proof buildings and his magnificent hydraulic machines. Having a few years ago directed his constructive genius to the building of iron steam-ships, he became thereby well acquainted with the prodigious stiffness and strength of which hollow girders of thin sheet iron were susceptible. He was naturally pitched upon by Mr. Stephenson, the engineer of the Chester and Holyhead Railway, as the fittest per- son to execute the tubular bridge which was regarded by him as the only means of carrying ponderous railway trains over the tremendous sea-gulf of Menai's Straits or Conway's roaring flood. The tidal torrents of these two places being deep and rapid, required to be crossed by bridges of extraordinary span and strength. No centrings or other substructures usually resorted to for mounting such huge pontitectures could be erected. In such a dilemma, the most obvious resource of the engineer was a sus- pension bridge; but the failure of more than one attempt of that kind had proved the impossibility of running railway trains over such bridges with safety. Under Mr. Stephenson's direction, numerous other schemes had been devised. Both timber and cast-iron arches had been thought of; and a model of a very handsome bridge for crossing the Menai Straits on the latter principle had been constructed, and submitted to the consideration of a parliamentary committee. The possibility of throwing cast-iron arches over so great a span as 450 ft was however questionable ; and the security of such a bridge must have been endangered by the great changes which the material would have been subjected to from atmospheric influences, and from vibrations produced by the passage of heavy trains. But a more important objection even than these caused the withdrawal of this design. The Lords Commissioners of the Admiralty, as conservator qf the navigation, opposed the erection of any structure which should offer a hindrance to the free passage of vessels under it, and insisted on a clear headway of 105 ft from the level of high water. Mr. Stephenstm then conceived the original idea of a huge tubular bridge, to be constructed of riveted plates, and sup- ported by chains,* and of such dimensions as to allow of the passage of locomotive engines and railway trains through the interior of it The illustrious Galileo, in de- monstrating the strength of tubular structures, adverted to the quills of birds and the stalks of corn ; but in our days we see that idea amplified into colossal dimensions. «i Y/^ ^'^'* reference to this expedient, after all others had been found inapplicable, that Mr. Fairbairn was consulted by him, and requested to give his opinion— first, as to the practicability of the scheme ; and secondly, as to the means necessary for carrr- mg It out The consultation took place early in April, 1845. Mr. Stephenson con- ceived that the tube should be either of a circular or egg-shaped sectional form ; and he was strongly impressed with the primary importance of the use of chains, placing his reliance in them as the principal support of the bridge. He never for a moment enter- tained the idea of making the tube self-supporting. The wrought-iron tube, according to his Idea, was indeed entirely subservient to the chains, and intended to operate from Its rigidity and weight as a stiffener, and to prevent, or at least to some extent coun- teract, the catenary principle of construction. " February 23d, 1846. ** My dear Sir, "I have been considering the principle on which you purpose attaching the chain for the support of the tube; and with every deference to your judgment, 1 am almost inclined to differ with you upon that point "It appears to me that the great and important consideration is to relieve the strain upon the tube. It is quite clear that a series of chains on each side of the plates, well fitted and tightly screwed up, would tend to stiffen the sides, and give greater rigidity to these parts. This is, however, not what is wanted. The rigidity is required on the top side; as in all the experiments the sides seldom get out of form unless distorted by the crushing of the top side. Under these circumstances the stiffening should in my opinion be on the top platform of the tube"— William Fairbairn to Mr. Robert Ste- phenson.^ For many months afterwards, and even up to the time of the experiments on the model tube in December 1846, Mr. Stephenson insisted on the application of such chains. " I always felt," says Mr. Fairbairn, "that in a combination of two bodies, the one of a perfectly rigid, and the other of a flexible nature, there was a principle of weakness; for the vibrations to which the one would be subjected, would call into operation forces whose constant action upon the rivets and fastenings of the other could not but tend to loosen them, and thus, by a slow but sure agency, to break up the bridge.** In consequence of the favorable opinion entertained by Mr. Stephenson on the cylin- ♦ These chains, not only superfluotis hut dangerous, would have cost 150.0001 t Conway and Menai Bridges, by W, Fairbairn, C. E., p. 48. 43 672 FAIRBAIRN'S TUBULAR BRIDGES. FAIRBAIRN'S TUBULAR BRIDGES. 673 II drical tubes, it was deemed expedient to commence experiments upon models of that kind, and to extend them subsequently to elliptical tubes. Experiments carefully made, demonstrated the weakness of the'se two forms, and the vastly greater strength of the rectangular tubes, which were accordingly adopted with cellular top and bottom. In Mr. Stephenson's examination before the Select Committee of Railways of the House of Commons, 5th and 6th of May, 1845, he says: "I am instituting a series of experiments in conjunction with Mr. Fairbairn of Manchester, who is already in pos- session of experiments on iron ships, which place the thing beyond all doubt He has ascertained that a vessel of 250 ft in length supported at the ends will not yield with all tlie machinery in the middle. "Have your calculations been submitted to any other engineers? " / have made them, in conjunction with Mr. Fairbairn of Manchester, whose experience is greater than any other man's in England. There is an iron vessel now building by Mr. Fairbairn 220 ft in length; and he says that he will engage, that, when it is finished, it shall be }>ut down on the stocks at each end, and shall have 1000 tons of machinery in the middle of it and it will not affect it But that is not so strong as a tube, and therefore, any experiment that this would carry out, the tube would fully bear." The floating ofthejirst Conway tube — "The transport of a huge mass of iron 412 ft long, 26 ft 6 in. high, 15 ft wide, and weighing not less than 1300 tons, was a task of no ordinary difficulty. No former effort with which we are acquainted can, I think, be said to have equalled it, when the unwieldiness of its form, and the extraordinary natural difficulties to be encountered, are taken into consideration. Many of the works of the ancients are stupendous in conception and colossal in dimensions ; and it has been a constant matter of inquiry, in what manner a people, ignorant of the mechanical ap- pliances which we possess, could raise structures which have resisted all the inroads of time, and which are to the present generation objects of awe and admiration. In more recent times, the transport of the immense granite block which forms the base of the statue of Peter the Great at St Petersburg, was looked upon as a most extraordinary achievement ; but it cannot he said to have been so formidable an undertaking as the moving of the Conway tube. The granite block was a compact mass, being 42 ft at the base, 21 ft thick, and 17 ft high, and capable of being moved on rollers, Ac, to the raft which carried it down the Neva to the site of the city; but in the case of the Con- way tube, after the most anxious consideration, and when numerous schemes and pro- posals had been weighed, examined, and rejected, that of floating the mass on pontoons or barges was decided upon as the most feasible and most secure, the centre of gravity being in this case, necessarily raised several feet In addition to this disadvantage, the whole had to be handled and manoiuvred in probably the most difficult tideway in Europe, where the current rushes through a narrow gorge of great depth to fill the broad expanse of the inland bay, at a rate of 6 or 7 miles an hour ; and the utmost nicety had moreover to be observed in bringing the tube to its place, as there was only a clearance of 12 inches; that is, the distance between the opposite masses of masonry was only 12 inches greater than the length of the tube. All these obstacles may well be termed formidable; and I therefore conceive that the utmost praise is due to Mr. Stephenson for the admirable arrangements and contrivances which rendered the first attempt at so gigantic an operation perfectly successful" I have quoted these liberal remarks of Mr. Fairbairn in proof of his good feeling to- wards the engineer associated with him conformably to the Minute of the directors of the Chester and Holyhead Railway, of date May 13, 1846, already quoted. How defective, and even erroneous, Mr. Stephenson's conceptions were of the tubular girder construction so late as the 26th October, 1846, appears, from his stating in a letter of that date addressed to Mr. Fairbairn, "that this was not the first time he had the idea of employing wrought-iron tubular bridges; for three years ago, or there- abouts, I had erected at Ware, on the Northern and Eastern Railway, a cellular plat- form of wrought-iron. It was, in fact I believe, a counterpart of the proposed top of the Britannia bridge." r r r "As this statement," says Mr. Fairbairn, "has been frequently repeated since the letter was written, I feel myself called upon to show that Mr. Stephenson has no claim to originality in this bridge, and that it has no resemblance whatever, either in principle or construction, to the Conway or Britannia tubes. On the contrary, the bridge in question is constructed upon the principle of the common cast-iron girder bridge, each separate beam being formed of wrought-iron plates connected together by angle irons. This form of wrought-iron girder had been long in use before the erection of the "Ware Bridge ; and it is defective as well in principle as in construction ; the great body of the material is not in the top flanches, as it ought to be, in order to attain the section of greatest strength. In Experiments 14, 15, and 16 (see Appendix and p. 10 in the Report), it is clearly shown that the top flanche of a wrought-iron girder, if made solid, should be more than twice the area of the bottom flanche. Now it appears that the top flanche in the said bridge at Ware is to the bottom flanche as 4 to 15 nearly; an exceedingly defective structure. If this beam were turned upside down it would carry more than double the weight From the defective principle upon which the bridge is constructed, it is evident that Mr. Stephenson was not then acquainted with the proper form of wrought-iron girder bridges. Nor is this surprising, as no experimental facts were at that time in existence to show the diflFerence between the two resisting forces of compression and extension of wrought-iron beams.** — Conway and Britannia Bridges^ by Mr. Fairbairn, pp. 113, 114. "It is impossible to trace any analogy between a combination of this form of beam and a tubular girder with a cellular top. The beams in the Ware Bridge do not offer a united resistance to strain in the manner which beams with a cellular structure do ; on the contrary, each beam has its distinct part of the load to carry, and that imperfectly, for want of a due proportion in the top and bottom flanches." — Ibidem. A striking proof of the accuracy of Mr. Fairbairn is afforded by the fact, that it was not till the latter part of 1846, that Mr. Stephenson finally made up his mind to aban- don the use 'of the chains, for in the engravings of both the Conway and Britannia Bridges, which were published in that year, there is attached to them the name of Robert Stephenson, Esq., engineer. These drawings represent, with tolerable accuracy, the proportions and forms of the tubes of both bridges as they now exists vit, the long, low, rectangular galleries, which Mr. Fairbairn's experiments had shown to be much better adapted to the purpose than the elliptical tubes proposed by Mr. Stephenson. But mark, in both cases the chains are absolutely slwwn attached to the tubes. They are a prominent feature in the drawing, and therefore conclusive evidence that up to that time at least and notwithstanding the discovery of the increased strength and security to be derived from the adoption of the tube with a rectangular section, And the distribution of the material on the top side in the form of cells, Mr. Stephen- eon still thought the auxiliary support indispensable. From the moment that Mr. Fairbairn commenced this experimental investigation, the whole matter, as regarded the development of the best form of the tubes, was un- reservedly in his own hands. Mr. Stephenson was not present at the experiments, he neither superintended nor directed them, but was simply made acquainteawith results, and approved, when completed, what Mr. Fairbairn did. And now what did Mr. Fair- bairn's experiments show ? They first of all confirmed his own early opinion, that the security of the bridge, if built at all, must depend solely upon the self-contained strength of the tube, and that the application of any form of catenanr would introduce into the sU-ucture an agency of a destructive tendency. They proved the weakness and total in- adequacy of either of the sectional forms of tubes (cylindrical or elliptical), thought of by Mr. Stephenson. They led Mr. Fairbairn, after carefully observing all the signs and symptoms of weakness shown by the models when under strain, to recommend, as a stronger form of tube one having a rectangular section. They brought to light some curious and anomalous appearances exhibited by wrought-iron when subjected to a crushing force. They showed that tubes of a uniform distribution of material, when loaded with an increasing weight, first yielded on the upper side ; and this /a,^^l?'^'K^''^*'"^''^?^^"^"*^^^«^ ^«« ^^^^^^ from the^co^troners of the ?h ! f Ir V wf ^^""^^ 7^! ^i^ «*^o™P»«hed without hindrance or obstruction t^ the rights which they guarded The manner in which all these necessities were com? phed with 18 well known The Britannia and Conway Bridges exist, the pride ofTe TntTnTl P'^^r^' '^'"' *"".™P^^« ^^ ^^' constructive f rts. and immortal monu! ments to the men who were associated in their contrivance and execution. It is t^ be t£:!ir''""^'''^u'' '^^'^'^^T'"' «"^ "^*>"^« «h«"llates firmly riveted or fastened togrher%;rsubi^^^^^^^^ ^verv boSrr-.'''r5 "'* H? '^°^'"^ ^« ^''^^ ^'' ^^e law,^ which is ap^lieaSe t^ every body, be it solid or hollow, is observable. The parts of the girder above the ^^^'Itr'tl^^^''^''^''^^^^ - compresfive strain, w^ tLc extreme diffinU ''f ^'^l^^f^J.^^bjected to a force tending to draw them asunder! known Td in fK.^r ^r"^*^'rr ^"^ '^ ^''""^ P^^^*- ^ »-««»«t tension, were well pZI ' the earlier stages of the inquiry it was considered feasible, and frequent ^^^h^lTTL™^^!,*^^""^"-".^'^" P"""^ ^" such manner that these kno^n properties Txf erimLt L"ffl.^dTh "^- "' " ^' V^^ "PP^^ "'^'^ ^^"^^ «^^^ ^^ ^^e girder, Lt^;ery coLtr3°r fW K ^ ^"g««"'ty of the contrivance, and nature Son taught the P«t«S / ^ .u^^ unerring laws were not to be disregarded. This point beine charaitPr ^/.'h' ?"' '^^ ^iftribution of the metal in a tubullr giixier could^change hf character of the forces which would act upon it, Mr. Fairbai?n's great merit lies in ur>nlr^«T'^.H ''^-^.^'^t ^^ ^^^Pted his new material to those strains. In tie top Z ihFU \ 1^''^A^^ ^^ distributed it, in that beautiful cellular form which impart* riarflhl '"^' •^'''^ security to the structure, and in the bottom he connected the wlt^h^atTtrsTd'pYat!" "'""^ "'"' """"^'^' '^^ ^^'^"^^^^ ^' ^^« J-^^ The description of one of the best constructed tubular girders will give the most correct idea of their power and peculiarity. We select for iUustrl^io/ the beauS 503 FAIRBAIRN'S TUBULAR BRIDGES. 670 bridge erected across the Trent at Gainsborough. Fia 603 reoresentj, ,i ..^nn^i t &«.i thfL ^ • i" ".'" 'PV """"S "4 feet each. The width of road war war The w'dthTthf '."'T "•^' ''^ f ""« ^^P'^ ■■'""" f<"- « "J"""' «"« of "if way. ine width of the centre pier is 12 feet, and the tubular girders have a he»r;,>» 2d™ Z^ ''^?"'"" "' " 'f *• ^? «»* represents a cross sef tion7orm of ?hc m"?f ^f fcv.? li' "% """" f "■"" ''P'"'"' «"«"«»° i" order to make tl" peculiariUes thi^'Snsril™ Z bl f'"'' ^'^•'" °' '»'=''.s'"^" f™™ -"J '» -SriaTeet rn;;«Tofmreriar;U^from\l^:'Zl«^ T'^""' "'"•» K'"™"" paraboHc form and pr.ctie:«'^thT;r„;^rrf^^^^^^^^^ "'^'.V^; thicknesses instead of the linear dimensions of the part™^ ^ ^ pla^'I f ^"rett'd Wct'ht i„"7h^ '^"""J' '"""^ of '■"""e thicknesses of long rolled ^?rsZs\ttletat °H 'is^Sntd^^^^^ that part of the structure to one unbroken ^M . hi '?J^;r™;' 'f-'Vi'" '"^™''"'« the best distribution of form Each olateTs 19 w i ^ '( Pr«<='""'''le would be Uthickness according to itsposittlrotte'^in'tr^^UX^^nlpVo^tle^ tmonnt of material is accumulated. The bottom is necessarily connected to the 6id«8 of the girder by long bars of heavy L or angle iron, firmly riveted to both. 676 FAIRBAIRN»S TUBULAR BRIDGES. The Sides of the Girder.— The side plates are 2 feet wide throughout, and of uniform thickness, excepting in the immediate neighborhood of the piers and abutments, where they are strengthened and stiffened by pillars of strong T iron, to offer a due resistance to the dead weight of the girder itself. The joints are made with external covering plates 4| inches wide, and internal ribs of T iron, which suffice to keep the side plates rigid, and enable them to accomplish their duty of separating the top and bottom of the girder. The Top of the Girder.— In this part the principal novelty and ingenuity are obaerr- able. A single sheet of iron, like a sheet of paper is easily put out of shape by a com- pressive strain. It crumples up, and at once loses all power of resistance. A sheet of common writing paper, which when placed on edge will nearly support itself, when rolled into a cylinder, say of 1 inch diameter, will carry a considerable weight In the same manner a given sectional area of plate, if placed in that simple form in the top of the Trent girder, would crumple up with a comparatively small weight, but when distributed according to Mr. Fairbairn's tubular arrangement it offers extraordi- nary resistance to compression. FAIRBAIRN'S TUBULAR BRIDGES. 677 605 The value of this arrangement will be understood when it is stated that notwithstand- ing the superior tenacity of wronght-iron, a well constructed tubular girder only requires an excess of sectional area in the top over the bottom of i.. In the Trent girder (see ^. 604X the top compartment is 3 feet | inch wide, and 15 inches deep, divided bya vertical plate into two rectangular cells, and all firmly connected by rivets, and L inm . Those angle irons constitute important elements in its strength. Since the construction of the Trent bridge, the cost of construction of tubular girders has been much diminished by a different arrangement of the parts of the top compartment, as shown in the following. Jig. 506. This form is equally powerful in its resistance. When the span of the bridge 606 reaches 180 or 200 feet, the top compartment is arranged as shown in Jig. 507, and when it is under 60 feet as shown injig. 508. It will be noticed that in every case the eells are proportioned, so as to admit of the entrance of a man for the purposes of painting or repairs. 71*—- >} 7%e Cross Beams or Supports of the Roadway. — ^These are generally, and ought to be universally, made of iron. In the Trent bridge they are made hollow or box beams, as shown in the annexed figure, fig. 509. Their construction is now much simpler and equally good, thus^. 510. 510 Ttie Riveting. — ^Upon the judicious fas- tenings of the plates together depends in a great measure the safety of a tubular girder bridge. The system of riveting followed in the several parts should have reference to the strains which occur in those parta What are technically called "lap joints," where the ends of the plate overlap each other, and are connected by a single row of rivets, (vide fig. 511,) should be avoided in every part of the structure, as they have been proved to be weak and insufficient Mr. Fairbairn {Phil Trans, part ii. 1862) gives the value of single and double riveted joints, as 70 and 56 respectively, the solid plate being assumed to be 100. "Butt joints" and covering plates are used throughout the girder, the length and substance of these covering plates and the number of rivets varying according to situ- ation. In the top compartment the ends of the plates having been carefully fitted to each other, so as to take their portion of the strain the moment the load is applied, are covered by strips of sufficient width to receive a double row of rivets, one on each side of the joint» thus, as shown in fig. 512. This arrangement effectually prevents some such effect as indicated in^^. 513, which would occur were the lap joint used, and the load very great In the tops the rivets are generally spaced 8 inches apart from centre to centre. *i 678 FAIRBAIRN'S TUBULAR BRIDGES. "'f^'^^yf^wyyyaii -^^m 512 As before mentioned, instead of simple strips covering the vertical joints of the side plates, mside T iron bars are used to afford stiffness, and prevent the approach of the - top and bottom (vide fig. 514.) Thus, the rivete being spaced 8 inches, the strips give to the ex- ternal elevation of the girder the appearance of a series of panels. In the bottom an exceedinglj ingenious and beautiful arrangement of riveting has been in- troduced by Mr. Fairbairn. It is evident that to join two plates together (these two plates having to resist a force tending constantly to separate them) a certain number of rivets or pins i-« f*".^ required, and according to the old system of wz^^msszz^ J'^'J^ting, these rivets were placed in single rows along the edge of the plates, being in fact either single lap joints, or single butt jointa Suppose the plates \x\ fig. 515 to be each 2 feet wide, and . , , . \ inch thickj and that to connect them there were wanted 16 rivets, each 1 inch diameter. It is evident the resisting powers of P'ates are weakened exactly by the amount of material punched out, in this case one-third, the section of resistance bein^ through the line a 6, and not through the Jme c d. J3ut if these 16 rivets, instead of being placed all parallel with the joint, are arranged as shown in fig. 516 and covered with long " covering plates" instead 515 516 of "8tni)8, It is equally evident that they are in this position equally fitted to their duty of joining the plates, and that the punching has weakened the resting powers of the plates only ^i^ instead of |. These proportions will readily explain the saving in material and weight which Mr. Fairbairn's "chain riveting" has effected, and the following figure of the " bottom" of the Trent bridge will show how it is practically applied {fig. 517.) The joints of the angle irons in the bottom are also jointed by .|f,e!L ■^ 517 aocoo6o ioo^oi r. ^6^ i o'o e o e -! > 5TT3T" b o o e 3oOooaoccaoo o^ocola o a o p ) I o o>o eolo o o o o o&e o oo k— ;0 o g o 0-& 6 o o o c o o o c-Q- g y ^^"5^—6-^^^ Vq-Q-Q oTp-'r oT o ^d-ll^'o -^^Sfe- -^.i8r_„^ i' ioooo-, { o;«°Ooaicaoooooeoeoc eoa o e OOP o e o o oo o o o oo o -s: ■ OOO O 0!0 o o "i.'O ao oo oQOoi&o o y»« «'7 ^"'W"' "d veiy "Mancheflter, April 15.' " "William Fairbaibn." Strurturei. By \V. FairS E^ P F ?^ Vx. '^P'"'^? "> JJ""'""*' and other Chester indHol^h^nL-^ E.ver Conway and the Menai Straits on tie line of the n/w e^a ?a ^e S?rr?nf k'!^^^' T^ only attained that object, but it has established a «n^,VHM.oIf • 1 J of badges, by the development of the properties of a hitherto whTl arn^^^^^^ "^^ engineer of t*he present da^ t^o conqur obstacles "An „n5 J^ /°* 1*^ "^^""^ considered insurmountable. ^ tiio«f ^rf • 5^ f , '"■'^^ »»nportance to the scientific world, to the public and to be?oTanvthir d f'/ '"^''k'^' ^"^"'^ ^ ^'^^^ responsibilities on C eCeer' «Htnf!!^ • ^r^^°'^^ ^^""^^ ^^ accomplished, it became absolutely necessarfU) in' SudL.fK"'"-*'^ experimenteto determine the practicability of su Jh a sSre n r q u^? ^f Mr ^^.1' "^'^Zl^P^^'^'^^ ^?^ «^^«^ P^^P^'^^^^ ^^ the tube I? the " E^DerimP„fi?n ° i' ^?r '^ ?^°^' ^^ *^"'"^ «^'^«^«^ ^^ «o°d««t this inquiry taken^butl? iln K '"^*'' -i^'P^f^' ^^ rectangular tubes were accordingly unL- form were best^l^fw^^ ^'^" '^' '^"^^ ^^'^'"^^ ^^'^^ ^^««« ^^ ^ rectangular lorm were best calculated for the purpose. It was not, however until I had adnnf^/1 ^atentardlntctT/r M '"^ ^'^C'"* T' ™'"« «' 'l>rSar form beoam'eP^,^ cSny ?o7cL ^ '''»°''"«'y «qn«"« 'n that part to offer sufficient resistonce to the .imp'y'7ute°''tL\''°if!tiSMW h"'"''"'"" ^''^ the details of the e:.periment, but TtEe eir^t^ir^L'' ,w'''ft^^'^™5 necessary to adopt some other shape thanVhose t«I« as to effX,? AtllEi f ^l."''' ' w "■ ^ P'-opo'-tio- the top and bottom sides of the S enrur*: thfml.'^^r f ce tfTs Z "eT t'T^l '"^.r """'T' """^ '""' dearly indicated by the rectangular":,™ .id tKrCLn'^fTelfsTthrtl'sid: s::m7iS.:!^rhi"s7ng" ";,r**"" »» "■* -^^-^ '»- """■ ""o brd-LM: i^iTl'' discovery of the cellular top, and the greatly increased value which a tube fcalp^t^^ter^^^^^ experimen^ at one! suggLed a modified foTm of tubular giraer adapted to shorter spans. This description of bridge is now becomine eeneral • "eryTs:SS^^^^^^ of resistance, greWseeurity'and its adapSnTalmost wfe7if ro7pnn«ll! T 'k^^ "^f^ reasonably infer that wrought iron is cheaper and W no douhfT^^ll r^^^ with any other description of miterials. It may, and I aS d^av than <^^^^^^ urged, that wrought-iron is much more subject to oxidation Sn XiriL ?r^ ' n? *"" 'i^°' ' " <'''-t»»"«^°<^« ^^ch cannot be disputed ; but that artwo LatHf Zf n?r "fS 'g^^^^ oji the part of those having charge of the structure, du^WeTr afmos? anv Ki'77 three years will effectuali; protect it, and render it accTss ble L eve?v 3 tn?V^ ^Ti ^"^'^^^ *^^ girders, as now constructed, are nnf hflf Anl? ^ ?^ J r^.^"""^' ^^ ^^'^^^'^^ attention, I can see no reason why they should ^rn?fnn^K -f • 1^^ T l^ y«*"- Another objection brought againsFthisdc S tL Sr/ltirVl'^' "^^^ ^^^^'"i"? ^^«««; ^^^ fr«™ the numb r of joints, the whole is considered by some as dangerous and nsecure. Now as regards single rivet to get loose (unless the wo^k is impT^n/ x^ted) • 'and Tl^e'wL: ^c"r^ ?n^rw:'l/adTn."d^"^"t^^' ^^^^ A S^sc^iptio^" of Minting sotrraln^ f «^!V .• n ^^*P^^J^ r^^'f' «"y description of strain, as that of riveted platen stXLl'^t ^K- "°^rff^"^'^^? this subject; and' I have only to instance steam boilers, iron ships, and other vessels subjected to severe strain, as examples of FAIRBAIRN'S TUBULAR BRIDGES. 685 the strength and tenacity of riveted plates; in fact, rivets seldom or never get loose, but retain their position under every species of strain, and become, as it were, integral parts of the structure in common with the plates themselves. " In submitting these remarks to the consideration of the Commissioners, and in order to bear them out, it may not be uninteresting briefly to notice a few of the results of the experiments illustrative of this subject, and to show, with a greater degree of exactitude, the nature and value of this description of structure. ^ For these objects, I beg to insert a few of the earlier experiments on different descriptions of tubes, as re- corded in a report addressed to Mr. Stephenson and the directors of the Chester and Holyhead Railway, the particulars of which have already been before the public.** (Here follow the details of the experiments referred to.) The experiments, of which the above is a brief notice, have led to other improve- ments of great utility in practical science, and probably of equal value with those for which they were originally undertaken. " I have already stated that the difiiculty which the weakness of the material to resist a crushing force occasioned, was overcome by the adoption of the cellular form of top; but another, and, to my mind, very serious diflSculty presented itself, in the re- ductK>n in the strength of the plates at -the joints bjr the ordinary method of riveting, in the bottom and those parts where the tensile strain came into operation. This led to a new system of riveting, which, without weakening the body of the plate to so great an extent as formerly, gives a joint of almost equal strength with the plate itself, and thus adds in a most material manner to the^security of the structure. ** Consequent upon the experiments and the results obtained therefrom, numerous advantages presented themselves in the construction of wrought-iron girders. Tho strength, ductility, and comparative lightness of the material are the important elements of tiese girders ; and their elasticity, retention of form, and other properties, render them infinitely more secure than those composed of cast-iron, which, from the brittle nature of the material and imperfections in the castings, are liable to break without notice, and to which the wrought-iron girder is not subject This is, however, pro- bably of less importance, as the wrought-iron girder will be found not only cheaper, but (when well constructed, and upon the right principle) upwards of three times the strength of cast-iron. I have elsewhere stated to the Commissioners that the experi- ments attracted the notice generally of railway engineers, and, amongst others, that of Mr. Vignoles, who immediately gave an order for two wrought-iron girder bridges for the Blackburn and Bolton Railway Company: — one to cross the Liverpool and Leeds Canal, and the other over the turnpike road, both in the vicinity of Blackburn. These bridges were constructed simultaneously with another of similar form (with a cast-iron top) executed by Mr. Dockray, under the direction of Mr. Robert Stephenson, for carrying the turnpike road over the London and North-Western Railway at Camden Town. Those for the Blackburn and Bolton Railway were, however, the first adapted for railway traffic ; and although they are probably not so well proportioned as others since constructed, they nevertheless exhibit extraordinary powers of resistance ; and conceiving that a description of these bridges, with the tests to which they were sub- jected, might be useful, I have great pleasure in submitting the same, with the necea- aary drawings, to the consideration of the Commissioners. Explanation of the Engravings, descriptive of the Hollow Girder Bridge over the Turnpike Road near Blackburn. "Fig. 621 is an elevation or side view of the girder, each 66 ft long, and bedded on cast-iron base plates. *^Fig. 622 is a transverse section of the bridge, showing the sides of the cross-beams, and the cross sections of the outside and middle girders. "Fig. 523 is an enlarged transverse section of the outside girder, showing the at- tachment of the cross-beams, which are riveted to the bottom of the girder, exclusive of two bolts A A, which extend through the bottom plates and angle iron of the girder, and the top and bottom plates of the cross-beam. " Fig. 624 is an enlarged view of a part of the side of the large girder, exhibiting a transverse section of the cross beam, at b, which is made of wrought-iron, with the top and bottom plates so proportioned as to equalise its powers of resistance to the force of compression on the top, and that of tension on the bottom. It also exhibits the mode of riveting up the joints of the side plates with the covering strip c o c, and the addition- al strength as obtained by the attachment of T iron in the interior of the tube. ''Ftg. 525 is a plan of the bridge, showing on one side the platform and the rails, and on the other the cross-beams, which in this bridge are placed 6 ft. asunder ; but in those more recently constructed, I have placed them at distances of only 4 ft, and consider this arrangement preferable. Ill ; w i ) 686 FAIRBAIRN'S TUBULAR BRIDGES. 622 524 525 II II II n n II n I) II n n II n n 11^ ff "From the above description it will be seen that the whole is a strong and perfectly- rigid structure. With three longitudinal girders, a bridge of this description will support a load equally distributed of 760 tons; and in order to render it safe, under every species of strain, the middle girder is made nearly double the strength of those on the outside. This is essential, as two trains may be passing the bridge at the same moment; in which case the middle girder would be subjected to a pressure equal to double the load on the outside girders. "In the construction of bridgesof larger span, I generally prefer only two large longi- tudinal girders with strong cross-beams every three feef^ of sufficient length to admit two lines of rails, and sufficient room for two trains to pass at the same time. This mode of construction is preferable to the three girders, as it effects greater simplicity in the structure, and, from every appearance, renders the bridge equally effective and secure. "Having thus described tlie advantages peculiar to this description of bridge, I will now direct the attention of the Commissioners to the tests to which the Blackburn Bridge was subjected, previous to its opening for public traffic. The experiments were made in the presence of Captain Coddington, the Government Inspector of Railways, and Mr. Flanagan, engineer of the line, as follows: — "Three locomotive engines, weighing 60 tons, were coupled together, and passed over the bridge at velocities varying from 5 to 15, and 25 miles an hour. This load (60 tons) produced a deflection of -025 of a foot, or about -^^jths of an inch, and that without any perceptible increase in the deflection arising from the different rates of speed. In fact the deflection was found to be the same at all velocities. "After these tests were made, two wedges or inclined plates were fitted to the rails, jig. 626, at the middle of the bridge, and the engines run over them at the rate of 1 to 526 RAIL 7 10 miles an hour. The shock of the engines, as they respectively fell upon the girders, from a height of one inch, the thickness of the wedge at d, gave an increased deflection from 025 to -035 of a foot, and another set of wedges, \\ feet in height, gave a further increase of deflection (at the same velocity) of •035 to .045 of a foot "From the above experiments it appears evident that wrought-iron girders are well FATS. 687 calculated to resist not only a heavy dead weight, but the force of impact administered with an unsparing hand ; for, in fact, the girders were not injured by the blows inflicted by engines falling a height of \\ inches upon them, but restored themselves to their original position from which they were deflected by the shock. "On the whole we may, therefore, reasonably conclude that the present structure is not only the strongest, but the best calculated to resist strain when applied to lai^e spans, and particularly in situations where bridges^ with a perfectly horizontal soffit, are alone admissible. (Signed) ""William FAmBAiHN." " Manchester, ApHl 26th, 184a'' FAN (Eventail, Fr. ; Fdctur, Germ.) is usually a semi-circular piece of silk or paper, pasted double, enclosing slender slips of wood, ivory, tortoise-shell, whale-bone, &c., arranged like the tail of a peacock, in a radiatiag form, and susceptible of being folded together, and expanded at pleasure. This well-known hand ornament is used by ladies to cool their faces by agitating the air. Fans made of feathers, like the wing of a bird, have been employed from time immemorial by the natives of tropical countries. Fan is also the name of the apparatus for winnowing corn. For an account of thff powerful blowing and ventilating fan machine, see Foundry and Ventilator. FARINA (Farirusy Fr. ; MM, Germ.) is the flour of any species of corn, or starchj root, such as potato, arrow root, &c. See Bread and Stajich. FATS (Graisses, Fr. ; Fette, Germ.) occur in a great number of the animal tissues, being abundant under the skin in what is called the cellular membrane, round the kidneys, in the folds of the omentum, at the base of the heart, in the mediastinum, the mesenteric webb, as well as upon the surface of the intestines, and among many d the muscles. They vary in consistence, color, and smell, according to the animals from which they are obtained ; thus, they are generally fluid in the cetaceous tribes, soft and rank-flavored in the carnivorous, solid and nearly scentless in the ruminants, usually white and copious in well-fed young animals ; yellowish and more scanty in the old. Their consistence varies also according to the organ of their production ; being firmer under the skin, and in the neighborhood of the kidneys, than among the moveable viscera. Fat forms about one twentieth of the weight of a healthy animal. But as taken out by the butcher it is not pure, for being of a vesicular structure, it is always enclosed in membranes, mixed with blood, blood-vessels, lymphatics, &c. These foreign matters must first be separated in some measure mechanically, after the fat is minced small, and then more completely by melting it alon? with hot water, passing it through a sieve, and letting the whole cool very slowly. By this means a cake of cleansed fat will be obtained. Many plans of purifying fats have been proposed ; one of the best is to mix two per cent, of strong sulphuric acid with a quantity of water, in which the tallow is heated for some time with much stirring ; to allow the materials to cool, to take off the supernatant fat, and re-melt it with abundance of hot water. More tallow will thus be obtained, and that considerably whiter and harder than is usually procured by the melters. I have found that chlorine and chloride of lime do not improve, but rather deterio> rate, the appearance of oils and other fatty bodies. According to Appert, minced suet subjected to the action of high-pressure steam in a digester, at 250° or 260" F., becomes 80 hard as to be sonorous when struck, whiter, and capable, when made into candles, of giving a superior light. A convenient mode of rendering minced tallow, or melting it, it to put it in a tub, and drive steam through it from numerous orifices in ramifying pipes placed near the bottom. Mr. Watt assures me that his plan of purifying fats, patented in March, 1836, has been quite successful. He employs dilute sulphuric acid, to which he adds a little nitric acid, with a very small quantity of bichromate of potash, " to sup- ply oxygen ;" and some oxalic acid. These are mixed with the fat in the steaming tub. When the lumps of it are nearly dissolved, he takes for every ton of fat^ one pound of strong nitric acid, diluted with one quart of water; to which he adds two ounces of alcohol, naphtha, sulphuric ether, or spirits of turpentine; and after intro- ducing this mixture, he continues the boiling for half an hour. The fat is finally washed. As I do not comprehend the modus operandi of these ingredients, I shall abstain from any comment upon the recipe. Others have proposed to use vegetable or animal charcoal first, especially for rancid oils, then to heat them with a solution of sulphate of copper and common salt, which is supposed to precipitate the fetid albuminous matter. Milk of lime has been also pre- scribed: but it is, I believe, always detrimental. Davidson treats whale oil with infusion of tan, in order to separate the gelatine and albumine in flocks; next with water and chloride of lime, to destroy the smell; and lastly, with dilute sulphuric acid, to precipitate all the lime in the state of a sulphate. This is certainly one of the cheapest and most effective methods of purifying that substance. 44 688 FATS. FATS. 689 il Braconnot and Raspail have shown that solid animal fals are composed of vury small, microscopic, partly polygonal, partly renifonn particles, which are connected together by very thin membranes. These may be ruptured by mechanical means, then separated by triturating the fresh fats with cold water, and passing the unctuous matter througb a sieve. The particles float in the water, but eventually collect in a white granulai crj'stalline appearance, like starch. Each of them consists of a vesicular integument, of the nature of stearine, and an interior fluid like elaine, which aHerwards exudes. Th€ granules float in the water, but subside in spirits of wine. When digested in strong alcohol, the liquid part dissolves, but the solid remains. These particles diflfer in shape and size, as obtained from different animals ; those of the calf, ox, sheep, are polygonal, ^"*™ 5o ^° F5 0^ ®^ **" '"^^ *" diameter; those of the sow are kidney-shaped, and from JL *° 1 00 ' *^°*^ of man are polygonal, and from JL to i-; those of insects are spherical, and at most .^-1— of an inch. Fats all melt at a temperature much under 212* F. When strongly heated with con- tact of air, they diffuse white pungent fumes, then blacken, and lake fire. When sub- jected to distillation, they afford a changed fluid oil, carbureted hydrogen, and the other products of oily bodies. Exposed for a certain time to the atmosphere, they become rancid, and generate the same fat acids as they do by saponification. In their fresh state they are all composed principally of stearine, margarine, and oleine, with a little coloring and odorous matter ; and, in some species, hircine, from the goat ; phocenine, from the dolphin ; and butyrine, from butter. By subjecting them to a great degree ol cold, and compressing them between folds of blotting paper, a residuum is obtained, con- sisting chiefly of stearine and margarine ; the latter of which may be dissolved out by oil of turpentine. Beef and Mutton Suet. — ^When fresh, this is an insipid, nearly inodorous fat, of a firm consistence, almost insoluble in alcohol, entirely so if taken from the kidneys and mesen- teric web of the ox, the sheep, the goat, and the stag. It varies in its whiteness, con- sistence, and combustibility, with the species and health of the animals. That of the sheep is very white and very solid. They may all be purified in the manner above de- scribed. Strong sulphuric acid developes readily the acid fats by stirring it through melted suet. Alkali, by saponification, give rise at once to the three acids, — the stearic, margaric, and oleic. Beef suet consists of stearine, margarine, and oleine ; mutton and goat suet contain a little hircine. The specific gravity of the tallow of which common candles are made is, by my experiments, 0-936. The melting point of suet is from 98* to 104° F. The proportion of solid and fluid fat in it is somewhat variable, but the for- mer is in much larger proportion. Mutton suet is soluble in 44 parts of boiling alcohol, of 0*820 ; beef suet in 44 parts. Marrow fat consists of 76 of stearine, and 24 of oleine ; it melts at 115° F. Hog's-lard is soft, fusible at 81® F., convertible, by an alkaline solution, into a stearate, margarate, oleate, and glycerine. Its sp. grav. is 0*938, at 50° F. It consists of 62 of oleine, and 38 of stearine, in 100 parts. Goose-fat consists of 68 oleine and 32 stearine. Butter, in summer, consists of 60 of oleine and 40 of stearine ; in winter, of 35 of oleine, and 65 of stearine; the former substance being yellow, and the latter whito. Il differs, howe^ier, as produced from the milk of diflerent cows, and also according to their pasture. The ultimate constituents of stearine, according to Chevreul, are 79 carbon, 11*7 hydrogen, and 9*3 oxygen, in 100 parts. 1,294,009 cwts. of the tallow imported in 1837 were retained for internal consumption* See Margarine, Oleine, Soap, Stearine. The following statement is given on the authority of Braconnot:— Fresh Butter in summer in winter Hog's Lard Ox Marrow Goose Fat Duck Fat Ox Tallow Mutton Suet - Oleine. 60 87 62 24 68 72 26 26 Stearine. 40 68 88 76 82 28 76 74 M. Dnmas says that butter contains no stearine. The purification and decoloration of fats have been the object of many patents. Under Candle, Hempel's process for refining palm-oil and extracting its mai^arine is described. About 30 years ago, palm-oil was deprived of color to a certain degree by mixing with the melted oil, previously freed from its impurities by filtration, some dilute nitric acid, wooden vessels beiug used, and the oil being in a melted state. This process was both expensive and imperfect More lately whitening has been prescribed by means of chromic ncid, which, in the act of decomposition into chromic oxide, gives out pxyge". and thereby destroys vegetable colors. One pound of bichromate of potash in Rolution is to be mixed with two pounds of strong sulphuric acid, diluted before- hand with about two gallons of water; and this mixture is to be incorporated bv diligent stirring with 2 cwt of the filtered palm-oil, at a temperature of about 100 F., contained in a wooden vessel. The palm-oil is afterward to be washed in warm lime-water, to which some solution of chloride of lime may be advantageous!} added. By this process, well managed, a fat may be obtained from palm-oil fit for making white soap. Tallow may be also blanched to a consideiable degree by a like operation. Instead of sulphuric acid, the muriatic may be used to convert the chromic acid into chromic oxide in the above process, and thereby to liberate the blanching oxygen. The resulting solution of green muriate of chrome being freed from some adhering oil, is to be mixed with so much milk of lime as just to neutralize the excess of acid that may be present. The clear green muriate is then to be decomposed in a separate vessel, by the addition of well-slaked and sifted lime, in some excess. The green mix- ture of lime and chrome-oxide is now to be dried, and gently ignited, whereby it is converted into yellow chromate of lime, with some unsaturated lime. This compound being decomposed by dilute sulphuric acid, affords chromic acid, to be applied again in the decoloring of palm-oil, on the principles above explained. Mr. Prynne obtained a patent in March, 1840, for purifying tallow for the candle- maker, by heating it along with a solution of carbonate of potash or soda for 8 hours, letting the whole cool, removing the tallow to another vessel, heating it by means of tteam up to 206° F., along with dry carbonate of potash (pearlash) : letting this mix- ture cool very slowly ; and finally removing the tallow to a vessel enclosed in steam, so as to expel any subsidiary moisture. — Newton^s Journal, xxi. 258. A patent for a like purpose was obtained in June, 1842, by Mr. H. H. Watson. He avails himself of the blanching power of oxygen, as evolved from manganate of potash (chameleon mineral), in the act of its decomposition by acids, while in contact with the melted i'at. He prescribes a leaden vessel (a well-joined wooden tub will also serve) for operating upon the melted tallow, with one twentieth of its weight of the manganate, dissolved in water, and acidulated to the taste. The whole are to be well mixed, and gradually heated from 150^ up to 212° F., and maintained at that tem- perature for an hour. On account of the tendency of the dissolved manganate to spontaneous decomposition, it should be added to the dilute acid, mixed with the fat previously melted at the lowest temperature consistent with its fluidity. Palm-oil may be well blanched in the course of 12 hours by heat alone; if it be exposed in a layer of one or two inches to the air and sunshine, upon the surface of water kept up at nearly the boiling point by a coil of steam-pipes laid in the bottom of a square cistern of lead or wood, well jointed. Mr. Wilson, of Vauxhall, has applied centrifugal action to the separation of the more liquid from the more solid parts of fatty matters, using in preference tlie hydro-extractor :i used by Seyrig and Co., for drying textile fabrics. Mr. Wilson employs a stout cotton twill in addition to the wire grating; and in order to avoid the necessity of digging the concrete parts, and to prevent them from clogging the interstices for the discharge of the oily matter, he places the whole in a bag 8 inches in diameter, and of such length that when laid on the rotating machine against the grating the two ends will meet. The speed of the machine must be kept below that at which stearic acid or stearine would pass; which is known by the limpidity of the expressed fluid. To take advan- tage of the liquefying influence of heat, he keeps- the temperature of his room about 2P F. above that of the substances under treatment. ^The improved fat and candle factory, called Price's, of which Mr. Wilson, of Belmont, Vauxhall, seems to be the main conductor and schemer, is mounted upon a colossal scale. It has five separate works near London, great plantations of cocoa-nut trees in Ceylon, with a capital of about half a million sterling, an annual division of profits to the atnount of 50,000/., and it employs about 800 work-people, whose physical and moral well-being is well looked after by the benevolent manager of the whole concern. See Candles. Tallow imported for home consumption in 1850, 1,219,101 cwL ; in 1851, 1,085,660 cwt Gross amount of duty received, 78,270/. and 68,035/. respectively ; the duty being \d. per cwt from British possessions, and 1«. Q>d. per cwt from foreign countries. Fat Bleacuing. By transmitting streams of atmospheric air through heated palm- oil and other colored and odorous fatty matters, they are deprived so far of their color and smell as to be capable of forming white soaps. Mr. A Dunn obtained a patent for this object in 1843. lit S90 FEATHERS. FELTED CLOTH. 691 I' FAULTS {Failles, Fr.), in mining, are disturbances of the strata which interrupt ihe miner's operations, and put him at fault, to discover where ihe vein of ore or bed oj coal has been thrown by the convulsions of nature. Many examples of faults are exhibk ited under Pitcoal. FEATHERS (Plumesy Fr. ; Fedem, Germ.) constitute the subject of the manufacture of the Plumassier, a name given by the French (and also the English) to the artisan who prepares the feathers of certain birds foromaments to the toilet of ladies and for military men, and to him also who combines the feathers in various forms. We shall content our- selves with describing the method of preparing ostrich feathers, as most others are pre- pared in the same way. Several qualities are distinguished in the feathers of the ostrich ; those of the male, in particular, are whiter and more beautiful. Those upon the back and above the wings are preferred ; next, those of the wings, and lastly, of the tail. The down is merely the feathers of the other parts of the body, which vary in length from 4 to 14 inches. This down is black in the males, and gray in the females. The finest white feathers of the female have always their ends a little grayish, which lessens their lustre, and lowers their price. These feathers are imported from Algiers, Tunis, Alexandria, Madagascar, and Senegal; this being the order of their value. The scouring process is thus performed : — 4 ounces of while soap, cut small, are dis- solved in 4 pounds of water, moderately hot, in a large basin ; and the solution is made into a lather by beating with rods. Two bundles of the feathers, tied with packthread, are then introduced, and are rubbed well with the hands for five or six mmutes. After this soaping they are washed in clear water, as hot as the hand can bear. The whitening or bleaching is performed by three successive operations. 1. They are immersed in hot water mixed with Spanish white, and well agitated in it; •fler which they are washed in three waters in succession. 2. The feathers are azured in cold water containing a little indigo tied up in a fine cloth. They should be passed quickly through this bath. 3. They are sulphured in the same way as straw hats are (See Souhuring) ; they arc then dried by hanging uiwn cords, when they must be well shaken from time to time to open the fibres. The ribs are scraped with a bit of glass cut circularly, in order to render Ihero very- pliant. By drawing the edge of a blunt knife over the filaments they assume the curly form so much admired. The hairs of a dingy color are dyed black. For 20 pounds of feathers, a strong decoction is made of 25 pounds of logwood in a proper quantity of water. After boiling it for 6 hours, the wood is taken out, 3 pounds of copperas are thrown in ; and, after continuing the ebullition for 15 or 20 minutes, the copper is taken from the fire. The feathers are then immersed by handfuls, thoroughly soaked, and worked about ; and left in for two or three days. They are next cleansed in a very weak alkaline ley, and soaped three several times. When they feel very soft to the touch, they must be rinsed in cold water, and afterwards dried. While feathers are very difficult to dye a beautiful black. The acetate of iron is said to answer better than the sulphate, as a mordant. For dying other colors, the feathers should be previously well bleached by the action of the sun and the dew ; the end of the tube being cut sharp like a toothpick, and the feathers being planted singly in the grass. After fifteen days' exposure, they are cleared with soap as above described. Rose color or pink, is given with safflower and lemon juice. Deep red, by a boiling hot bath of Brazil wood, after aluming. Crimson. The above deep red feathers are passed through a bath of cudbear. Prune de Monsieur. The deep red is passed through an alkaline bath. Blues of every shade, are dyed with the indigo vat. Yellow ; after aluming, with a bath of turmeric or weld. Other lints may be obtained by a mixture of the above dyes. Feathers have some more useful employments than the decoration of the heads of women and soldiers. In one case, they supply us with a soft elastic down on which wc can repose our wearied frames, and enjoy sweet slumbers. Such are called bed feathers. Others are employed for writing, and these are called quills. Goose feathers are most esteemed for beds, and they are best when plucked from the living bird, which is done thrice a year, in spring, midsummer, arjl the beginning of harvest. The qualities sought for in bed feathers, are softness, elasticity, lightness, and warmth. Their only preparation when cleanly gathered is a slight beating to clear •way the loose matter, but for this purpose they must be first well dried either by the sun or a stove. Bleaching with lime water is a bad thing, as they never can be freed from white dust afterwards. The feathers of the eider duck, anas molUssima, called eider down, possess in a supe- rior degree all the good qualities of goose down. It is used only as a covering to beds, and never should be slept upon, as it thereby loses its elasticity. Quills for writing. These consist usually of the feathers plucked out of the wind's of geese. Dutch quills have been highly esteemed, as the Dutch were the first who hit upon the art of preparing them well, by clearing ihem both inside and outside from a fatty humor with whieh they are naturally impregnated, and which prevents the ink from flow- ing freely along the pens made with them. The Dutch for a long time employed hot cinders or ashes to attain this end ; and their secret was preserved very carefully, but it at length transpired, and the process was then improved. A bath of very fine sand mu^t be kept constantly at a suitable temperature, which is about 140° F. ; into this, the quiU end of the feather must be plunged, and left in il a few instants. On taking them out they must be strongly rubbed with a piece of flannel, after which they are found to be white and transparent. Both carbonate of potash in solution and dilute sulphuric acid have been tried to effect the same end, but without success. The yellow tint which gives auills the air of age, is produced by dipping them for a little in dilute muriatic acid, and Ihen making them perfectly dry. But this process must be preceded by the sand-bath operation. The above is the French process. QuillK are dressed by the London dealers in two ways; by the one, they remain of their latura color; by the other, they acquire a yellow tint. The former is called the Dutch method, and the principal workman is called a Dutcher. He siis before a small stove fire, Jnto which he thrusts the barrel of the quill for about a second, then lays its root quickly Jelow his blunt-edged knife called a hook, and, pressing this firmly with the left hand, iraws tl^e quill brK.kly through with his right. The bed on which the quill is laid to re- ceive this pressure is called the plate. It is a rectangular smooth lump of iron, about S nches long, i| broad, and 2^ thick, which is heated on his stove to about the 350th de- jree i-ahr. The hook is a ruler of about 15 inches in length, somewhat like the patten- caker s knife. Its fulcrum being formed at the one end by a hook and staple, and the power of pressure being applied by the hand at the other end. The quill, rendered soft ma elastic by the heat, endures the strong scraping action of the tool, and thus geU stripped of Its opaque outer membrane, without hazard of being split. A skilful work- man can pass 2000 quills through his liands in a day of 10 hours. They are next cleaned by being scrubbed by a woman with a piece of rough dog-fish »Kin, and bnally lied up by a man in one quarter of a hundred bundles. In another mode of dressing quills, they are steeped a night in decoction of turmeric, to stain them yellow; taken out and dried in warm sand contained in a pot, then scraped bv the Dutcher as above described. The first are reckoned to make the best pens, though •he second may appear more beautiful. Crow quills for draughtsmen, as well as swan quills, are prepared in the same way. lelnT" f '"^^'^^'i,^'^^"? ^e>l-fed living birds have most elasticity, and are least subjelt fo ^!^? r m""- T*"^ ^u' ^'^ '^""'^ P^"^'^^'^' «^ ^h'*=h a^e spontaneously cast n the month .f May or June, because they are then fully ripe. In the goose's wing the five aU Z n ■"' If '^"/^ Tu '"^"""" ^"^ ^^"^'"-^- The first is ihe hardest and roundest of all but ."-e shortest. The next two are the best of the five. Thev are sorted into those of he I ight and the left wing, which are diflerently bent. The heaviest quills are, g^ preparation ' ^^^^^' steaming for four hours has been proposed as a good FECULA (Fecule, Fr. ; Siarkemehl, Germ.) sometimes signifies corn flour, sometimes starch from whatever source obtained. ' iomeumes .^^^^^.^f-'^^.iOr^hose, Fr ; Feldspalh, Gevm.) is a mineral crystallizing in oblique rhomhoidal prisms, susceptible of two clivages; lustre more pearly than vitreous^ spec grav. 2.39 to 2..58 ; scratches glass; yields no water when calcined ; fuble a! Ihe blowpipe into a white enamel; not aflected by acids. The liquid kft from it. analyt,cal treatment with nitrate of baryta, nitric acid, and carbonate of amZn a^ aflords on evapora ion an alkaline residuum which precipitates plalina from its "hSe and appears from tins as well as other tests, to be potash. Feldspar consists of-sii c^' 66-70 ; alumina 17-50; potash, 12; lime, 125; oxyde of iron, 0-75. Rose. Th5 ^e\17i'L'rr'r'''"'"''^ "[""•''' ^"^ •" ''' decomposed state furnishes the CZes. ' "^ """'^ "'"'^ ''' ^^^ porcelain and best pottery manu- FK LTED CLOTH Tliis woollen fabric, made without spinning and weaving, was made the subject of a patent by Mr. T R. Williams in February, 1850. A copious d.'scnption of the process is given in Newton?8 Journal xxii 1 Varuhlud or Japanned Felt is made by imbuing the stuff of coarse hat bodies with di-v.M- „il, preparea by boiling 50 lbs. of linseed oil with white lead, litharge, and uu.Ur, <,t .>aeh one pound. The felt is to be dried in a stove, and then polished by IM..MI.M. sione. Five or six coats of oil are required. The surface is at last varnished W lu'i. the ol.ject IS intended to be stiflf, like visors, the fabric is to be impregnated first 692 FERMENT. FERMENTATION. 693 of all with flour-paste, then stove-dried, cut into the desired shape, next imbued with the drying-oil, and pumiced repeatedly; lastly placed, to the number of 20, in a hot iron mould, and exposed to strong pressure. Japanned hats, made in this way, are sold in France at 1«. 3c?. a piece ; and they will stand several years' wear. FELTING. {Feutrage, Fr.; Mlzen, Germ.) is the process by which loose flocks of wool, and hairs of various animals, as the beaver, rabbit, hare, Ac, are mutually in- terlaced into a compact textile fabric. The first step toward making felt is to mix, in the proper proportions, the different kinds of fibres intended to form the stuff; and then, by the vibratory strokes of the bowstring, to toss them up in the air, and to cause them to fall as irregularly as possible, upon the table, opened, spread, and scattered. The workman covers this layer of loose flocks with a piece of thick blanket stuff slightly moistened; he presses it with his hands, moving the hairs backward and forward in all directions. Thus the different fibres get interlaced, by their ends pursuing ever tortuous paths ; their vennioular motion being always, however, root foremost As the matting geti denser, the hand pressure should be increased in order to overcome the in creasing resistance to the decussation. A first thin sheet of soft spongy felt being now formed, a second is condensed upon it in like manner, and then a third, till the requisite strength and thickness be obtained. These different pieces are successively brought together disposed n a way suitable to the wished-for article, and united by continued dexterous pressure. The slufl" must be next subjected to the fulling-mill. See Hat Manufacture. FERMENT (Eng. and Fr. ; Hefe, Germ.) is the substance which, when added in a small quantity to vegetable or animal fluids, tends to excite those intestine motions and changes which accompany fermentation. It seems to be the result of an alteration which ▼eietable albumen and gluten undergo with contact of air amidst a fermenting mass. The precipitate or lees which fall down when fermentation is finished consist of a mix- ture of the fermenting principle with the insoluble matters contained in the ferijented liquor, some of which, like hordeine, existed in the worts, and others are probably genera- ted at the time. To prepare a pure ferment, or at least a compound rich in that principle, the precipi- tate separated during the fermentation of a clear infusion of mall, commonly called yeast or barm, is made use of. This pasty matter must be washci in cold distilled water, drained and squeezed between the folds of blotting paper. By this treatment it becomes a pulverulent mass, composed of small transparent grains, yellowish gray when viewed in the compound microscope. It contains mucli water, and is therefore soft, like moist gluten and albumen. When dried, it becomes like these bodies, translucid, yellowish brown, horny, hard, and brittle. la the soft humid state it is insipid, inodorous, in- soluble in water and alcohol. If, in this state, the ferment be left to itself at a tempera- ture of from 60° to 70' F., but not in too dry a situation, it putrefies with the same phe- nomena as vegetable gluten and albumen, and leaves, like them, a residuum resembling old cheese. At the beginning of this change, particularly if the ferment be enclosed in a limited portion of air, there is an absorption of oxygen gas with a fivefold disengagement of car- bonic acid gas; while acetic acid makes its appearance in the substance. When distilled by itself it affords the same products as gluten. Dilute acids dissolve it very readily ; and so does potash with the production of ammonia, a peculiar circumstance, for in dis- solving gluten the alkali causes no such evolution. The property possessed by yeast of determining the fermentation of a properly diluted solution of sugar is very fleeting, and is lost by very trifling alterations. It is destroyed by complete desiccation, and cannot be restored by moistening it again. The attempts made in London to squeeze out the liquid part of yeast in bags placed in a powerful press, and to obtain a solid cake, in order to transport ferment to India, have had but a very partial success ; for its virtue is so impaired that it will rarely excite a perfect fermenta- tion in the best prepared worts. The same method is adopted in Germany, to send yeast to only moderate distances ; and therefore with more advantage. If yeast be boiled for ten minutes, it loses the greater part of its fermenting power, and by longer boiling it becomes inert. When alcohol is poured upon yeast, it immediately destroys its fermenting faculties, though, on filtering it off, it seems to carry no remarkable principle with it. One thou- sandth part of sulphuric acid equally deprives yeast of its peculiar property, and so does a little strong acetic acid. All the acids and the salts, especially those which part readily with their oxygen, produce the same efl'ect. A very small quantity of sulphurous acid, or sulphites, mustard powder, particularly the volatile oil of mustard, and in general the volatile oils that contain sulphur, as well as the vegetables which yield them, such as horse-radish and garlic, all kill the fermenting agent. Lastly, fermentation is completely •topped by a moderate depression of temperature. During fermentation the yeast undergoes a change; it loses the property of causing another wort to ferment. This change probably depends upon the chemical reaction between the ferment and the sugar that is decomposed ; for a certain quantity of yeast can effect the fermentation of only a certain quantity of sugar, and all the sugar exceeding this quantity remains unaltered in the liquor. It has been concluded from some rather loose experiments, that one part and a half of yeast (supposed to be in the dry state), is adequate to the fermentation of a solution of 100 parts of pure sugar. When such a solution is fermented by the precise proportion of yeast, the fermenting principle is exhausted, for no new yeast is formed in it. There is a deposit indeed to about half the weight of the yeast employed, of a white matter insoluble in water, which affords no ammonia by dry distillation, and is incapable of acting as a ferment upon a fresh saccharine solution. Of all the bodies convertible into yeast during fermentation, vegetable gluten and albumen possess the most rapid and energetic powers. But ordinary glue, isinglass, animal fibrine, curd or caseum, albumine, urine, and other azotized substances, all enjoy the property of causing a solution of sugar to ferment; with this difference, that whilst yeast can establish a complete fermentation in less than an hour, at a tem- perature of about 68'-', the above substances require several days, with a heat of from 77° to 87*^ F, for becoming ferments, and for occasioning fermentation. Substance! devoid of nitrogen do not produce a ferment FERMENTATION. (Eng. and Fr. ; Gahrung, Germ.) When organic substances, under the influence of water, air, and warmth, are abandoned to the reciprocal operation of their proximate principles (sugar, starch, gluten, &c.), they are entirely changed and decomposed, so that their ultimate principles (oxygen, hydrogen, carbon, and in some cases azote) combine in new proportions, and thus give birth to various new compounds. To this process, the general name of fermentation has been given. These operations and their products differ according to the differences of the substance?, and of the circumstan- ces in which they are placed. The following may be enumerated as sufficiently distinct species of fermentation. 1. The saccharine fermentation, in which starch and gum are changed into sugar. 2. The vinous fermentation, in which sugar is converted into alco- hol. 3. The mucilaginous fermentation, in which sugar is converted into slime, instead of alcohol. 4. The acetous fermentation, in which alcohol and other substances are con* verted into vinegar. 5. The putrid fermentation or putrefaction, which characterizes particularly the decomposition of azotized organic substances. I. The saccharine fermentation. When a paste made by boiling one part of starch with twelve parts of water is left entirely to itself, water merely being stirred in as it evaporates, at the end of a month or two in summer weather it is changed into sugar, equal in weight to from one third to one half of the starch, and into gum, equal to from one fifth to one tenth, with a residuum of starch paste somewhat altered. This sac- charifying process advances much quicker through the co-operation of vegetable albu- mine or gluten, acting as a ferment. If we boil two parts of potato starch into a paste with twenty parts of water, mix this paste with one part of the gluten of wheat flour, and set the mixture for 8 hours in a temperature of from 122* to 167° F., the mixture soon loses its pasty character, and becomes by degrees limpid, transparent, and sweet, passing at the same lime first into gum, and then into sugar. The remainder consists of the unchanged starch with the altered gluten, which has become sour, and has lost the faculty of acting upon fresh portions of starch. It is probable, however, that the sugar formation in the first case, when the starch undergoes a spontaneous change, may be due to the action of a small portion of gluten and albumine left in the starch, since a putrefactive smell is eventually evolved indicative of that azotized matter. The gum into which during this process the starch is first converted, and which becomes afterwards sugar, is of the same nature as British gum, formed by the roasting of starch. This production of sugar takes place in the germination and kiln-drying of malt ; and the mashing of the brewer as well as the sweetening of bread in baking, rests upon the same principles. In many cases the vinous fermentation precedes the saccharification, or accompanies it ; the starchy parts of the fermenting mass changing into sugar, while the previously formed sugar becomes wine or beer. In the sweetening of fruits by keeping, a similar process occurs ; the gummy and starchy fibres become sugar from the action of the glutinous ferment which they contain ; as happens also to the juices of many fruits which sweeten for a little while after they have been expressed. The nature of this susar formation through the influence of gluten upon starch, is un- doubtedly the same as the conversion of starch into sugar, by boiling it with sulphuric acid ; though the whole theory of this change is not entirely developed- The most energetic substance for the conversion of starch into sugar, is the malt of barley. According to the researches of Payen and Persoz, the gum which by thi« 694 FERMENTATION. FERMENTATION. 695 Ai process is first formed, may be prevented from going into sugar, hy merely exposing it to a boiling heat, and hence we have it in our power either to make sugar or gum at pleasure. Of finely ground malt from 10 to 25 parts must be taken for 100 parts of starch. Into a pan placed in a water hath, 400 parts of water being warmed to from 77*^ to 86^^ F., the ground malt must be stirred in, and the temperature must be raised to 140°. The 100 parts of starch must now be added, and well mixed. The heat is then to be increased to 158*^ F. ; and be so regulated that it shall not fall below 149°, nor rise above 167°. In the course of 20 or 30 minutes the originally milky and pasty liquid will become graduall^r more attenuated, and eventually it will turn as fluid nearly as water. This is the point of time in which the starch has passed into gum, or into the substance lately denominated dextrine by the chemists. Should this mucilaginous matter, which appears to be a mixture of gum and a little starchy sugar, be wished for in that state, the temperature of the liquid must be suddenly raised to the boiling pointy whereby the further action of the malt upon it is stopped. But on the other hand, if sugar be desired, then the temperature mtist be steadily maintained at from 158° to 167° *or three quarters of an hour, in which time the greater Dart of the starch will have become sugar, and from the evaporation of the fluid a starchy syrup will be obtained, entirely similar to that procurable by the action of very dilute sulphuric acid upon itarch. gagar, and from the evaporation of the fluid a starchy sirup will be obtained, entirely similar to that procurable by the action of verj- dilute sulphuric acid upon starch. The substance which operates this saccharine change, or the appropriate yeast of the sugar fermentation, which had been previously imagined to be a residuum of gluien or vegetable albumen in the germinated grain, has been traced by Payen and Persoz to a peculiar proximate vegetable principle called by them diastase. This substance is gen- erated during the germination of barley, oats, and wheat, and may be obtained separate./ by infusing the ground malt in a small quantity of cold water, straining ofl* the liquor, then filtering it, and heating the clear solution in a water-bath to the temperature of 158° F. The greater part of the vegetable albumen is thus coagulated, and must be separated by a fresh filtration; the liquid is afterwards treated with alcohol as long as the flocculent precipitate of diastase falls. In order to purify it still more complelely from the azotized matter, it may be once more dissolved in water, and again precipitated by alcohol. When dried at a low temperature, it appears as a white solid, which con- tains no azote, is insoluble in strong alcohol, but dissolves in weak alcohol and water. Its solution is neutral and tasteless ; and if left to itself, it changes spontaneously, sooner or later, according to the degree of warmth, and becomes sour. At the temperature of from 149° to 168°, it has the property of converting starch into gum or dexirinc, and sugar; and, when sufficiently pure, it does this with such energy, that one pari of it is capable of saccharifying 2000 parts of dry starch. It acts the more rapidly the larger its proportion. Whenever the solution of diastase with starch or dextrine has beec heated to the boiling point, it loses the property of transforming these substances. One hundred parts of well malted barley appear to contain about one part of this new body. 2. Tke Vinous Fermentation. — In this fermentation the sugar existing in watery solu- tion is, by the operation of the ferment or yeast, converted into alcohol, with disengage- ment of carbonic acid gas. If we dissolve one part of pure sugar in ten parts of water, and leave the solution in a temperature of from 68° to 77° F., which is that iik>sI favor- able to fermentation, it will remain unaltered. But if we stir into that solution some beer yeast, the phenomena of fermentation soon appear in the above circumstances ; for car- bonic acid gas is evolved, with intestine movements of the liquid, and an increase of its temperature. A body of yeast rises to the surface, and exhibits a continual formation and rupture of air bubbles. At length the sugar being in a great measure decomposed, the motions cease, the liquor becomes clear, and instead of being a sirup, it is now a dilute alcohol. The yeast has by this time fallen to the bottom in a somewhat compact form, and of a whitish color, deprived of the property of exciting fermentation in fresh sirup, provided no undue excess of it was added at first, for that alone would remain elfective. Experience shows that for the conversion of a determinate quantity of sugar by fermen- tation, a determinate quantity of yeast is necessary, which has been estimated at abou; 1| per cent, in the dry state. When the yeast has been decomposed by fermenting its definite proportion of sugar, it loses its fermentable properly, and leaves the excess of sugar unaffected, forming a sweet vinous solution. The same thing happens if the yeast be separated from the wort by a filler in the progress of the fermentation, for then all intestine motion speedily stops, although much saccharine matter remains. In the juices of sweet fruits, of grapes, for example, the ferment is intimately asso- ciated with the sugar. It is at first soluble and inactive, till it absorbs oxygen from the atmosphere, whereby it becomes an operative ferment, but, at the same time, insoluble, so as to precipitate at the end of the process. When the expressed juice of the grape, or mtutf is enclosed in ^ vessel out of contact of air, and there subjected to the heat of boiling water, the small portion of oxygen present is rendered inactive, and the liquor ex- periences no fermentative change. If the grapes be squeezed in an atmosphere deprived of oxygen, and confined in the same, the juice will also remain unaltered. Recently ex* pressed grape juice is limpid, and manifests the commencement of fermentation by the separation of the yeasty substance, which can take place only with access of air. The Bolution becomes turbid after a certain time, gas begins to be evolved, and the separated ferment decomposes the sugar. At the end of the process the yeast collects at the bot- tom of the vessel, usually in larger quantity than was suflicient to complete the fermen- tation ; and hence a considerable portion of it possesses still the fermentative faculty. The fermentation itself, when once begun, that is, whenever the yeasty particles arc eiolvedand float in the liquid, for which evolution a very minute quantity of oxygen is suflicient, is thenceforth independent of the contact of air, and goes on as well in close as in open vessels ; so that the production of alcohol and carbonic acid depends solely upon the mutual reaction of the ferment and the sugar. The yeast, which may be obtained tolerably pure from a fine infusion of malt in a state of fermentation, after being washed with cold water to separate the soluble, gummy, and saccharine matter, and after being pressed between fclds of blotting paper, consti- tutes a pulverulent, grayish yellow, granular substance, destitute of both taste and smell, insoluble both in water and alcohol. Cold water dissolves, indeed, only ^^y and boiling water very little more. The essentially operative constituent of yeast is a peculiar azotized matter, which m the wine vat is mixed with some tartar and other salts, and in the beer tun with gum, starch, &c. This animalized substance may be obtained in a separate slate, according to Braconnot, by acting upon the washed yeast powder with a weak ley of carbonate oi potash, and by decomposing the solution wiih vinegar, whereby the matter is thrown down in a gelatinous form. The substance thus obtained is insoluble in cold water and alcohol, but dissolves readily in verj' dilute alkaline leys, and even in lime water When diflfused through water, it assumes a homogeneous aspect, as if it were really dissolved ; but when this mixture is heated, the animalized matter coagulates, and separates in thick flocks. In this state it has lost its former properties, being no longer soluble in alkaline leys, even when concentrated. Acids exercise no solvent power over this peculiar matter ; they precipitate it from its solutions, as do also the earthy and metallic salts, which, moreover, combine with it. This is also the case with tannin. The combination of the ferment stuff with acids increases the stability of its constitution, and counteracts its tendency to influence solutions of sugar. These proi)erlies of the operative principle of yeast explain many of the phenomena of fermentation, as we shall presently see. The animalized matter of yeast resembles gluten, albumen, caseum, and other azotized substances ; if any one of these be put into a saccharine solution ready for fermentation, it will begin to operate a change, when aided by warmth and time, if it be previously decomposed in some measure to facilitate its influence ; or if these substances be brought into a slightly putrescent state beforehand, they will cause more speedy fermentation. Thus white of egg, when added to saccharine liquors, requires a period of three weeks, with a temperature of 96° F., before it will excite fermentation ; afterwards the excess of the albumen forms a precipitate which may be used instead of yeast upon other sweet worts. The rapidity with which such azotized substances are capable of being converted into ferments of more or less purity and power is very variable ; vegetable gluien and albumen being best fitted for this purpose. This conversion is accelerated when the sweet liquor in which the substance is diffused or dissolved has already begun to ferment; whence it appears that the presence of carbonic acid gas, combined with the liquor, is here of singular influence. Upon it, in fact, the formation and elimination of the yeast in fermenting liquors depend. A solution of pure sugar, which has been made to ferment by the addition of yeast, furnishes no new yeast ; but there remains after the process a portion of the yeast origi- nally mixed, in an altered inoperative condition, should its quantity have been exactly adequate to the decomposition of the sugar, or in an operative state, should the quantity have been originally excessive. But if the fermentable liquor contains vegetable albumen and gluten, as is commonly the case with the sweet juices of fruits and beer worts, these substances become clianged into ferments in the course of the fermentation induced by the yeast, and, being super- fluous, so to speak, for that particular process, they remain entire at the end, and may be collected for use in other operations. Upon this principle is founded the increased production of yeast, and the manufacture of what has been called artificial barm, in which the fermentation is conducted chiefly with a view to the formation of yeast. To the fermenting mass, those kinds of meal are •dded, which abound in albumen and gluten, as barley, beans, or wheat, for instance ; 696 FERMENTATION. i>' t. It and the process is similar to the production of a great lump of leaven, from the action of a small piece of it upon dough. The following prescription will illustrate this subject. Take three ounces of bean flour, add to it five quarts of boiling water, and boil th« mixture for half an hour. Pour the decoction into a vessel, and stir into it, while hot, 56 ounces of wheaten flour. After the mixture cools to the temperature of 54° F., add to it about two quarts of beer barm, stirring the whole well together. About 24 hours after the commencement of the fermentation, incorporate with the mixture 1 12 ounces of barley or bean flour, till it becomes a uniform dough, which must be thoroughly kneaded, rolled out into cakes about an inch thick, and cut into pieces of the size of a dollar. These cakelets must be dried upon laths in the sun in favorable weather, and then put up in a dry situation. For use, one of these discs is to be broken into pieces, laid in warm water, and set in a warm place during 12 hours. The soft mass will then serve the purpose of beer yeast. Or we may mix equal parts of barley malt, wheat malt, and crushed rye, pour water at the temperature of 122° F. over them into a tub till it stand a span above their sur- face ; then stir well together, and allow the whole to remain at rest for a few hours, till it cools to about 65° F. We must now add for each pound of the mingled meals, a quarter nf an ounce of beer barm. The tub must be then covered, and preserved at a temperature of 63° F. The husks, as they begin lo rise to the surface, in consequence of the fermentation, must be taken ofl" and squeezed through a cloth over the vessel. Wlien the meal comes afterwards to subside to the bottom, the whole musi be strained Ihrough a canvass bag, and freed from the superfluous moisture by squeezin-, The bag with its doughy mass must next be surrounded with dry ashes, lo remove the remaining humidity, and to arrest any further fermentation. This consistent ferment may be tised instead of beer yeast. It is difficult to prepare an artificial yeast without barm. The best process for this purpose is the followins. Take five parts of honey, one part of powdered tartar, and sixteen parts of wheat or barley malt, stir the whole in water of the temperature of 122* F., and place in a fermenting heat; when the yeast will, as usual, be eliminated. The change which gluten or vegetable albumen undergoes in the different kinds of meal, when it becomes a ferment, consists apparently in an oxydation, since analysis shows that this ferment contains more oxygen than gluten does. It has been already stated that yeast in its liquid condition readily putrefies, and becomes altogether useless for the process of fermentation. In order to preserve it for some time, it must be dried to such a degree as to resist spontaneous decomposition without losing its fermentative faculty; but completely dried yeast loses that properly, and does not recover it by being again moistened. Beer barm may be dried after being washed sevei'al times with cold water, till the last quantity comes off clear; but the in- soluble portion must be allowed to settle fully before the water is poured away from it. The residuum being freed as much as possible from water, by drainage and pressure between flannel cloths, is to be dried in the shade by a current of warm air as quickly as possible, with the aid of frequent turning over. It must be afterwards kept in dry earthen vessels. Yeast may also be preserved a short lime in activity by being kneaded with as much barley or wheat flour as it can take up without losing the doughy con- sistence. Dried yeast has, however, always an impaired activity. The easiest and most certain method of preserving yeast in its primitive power, is by mixing it, after pressure in flannel, with as much pulverized sugar as will render it dry, and putting up the mix- ture in air-tight vessels. The fermentative power of yeast is destroyed by the following means : 1 . as already stated, by making it completely dry either by the evaporation of the water, or its abstraction by alcohol ; 2. by boiling, which if continued for ten minutes renders yeast quite inoperative ; 3. by the action of such substances as dissolve out its essential constituents; by alkalis, for instance, since the particles of yeast seem to be operative only in their insoluble granular state ; 4. by such substances as form combina- tions with it, and thereby either alter its nature, or at least increase the cohesion of its constituent parts, so that they can no longer operate upon sweet liquors by the decompo- sing affinity of its ultimate particles. Such bodies are the acids, especially the mineral ones, tannin and most salts, particularly ihe metallic, which unite with the yeast into new compounds. The volatile oils which contain sulphur exercise the same paralyzing influ- ence upon yeast. The circumstances which promote, and are necessary to, the vinous fermentation are, conformably to the above views, the following-.— 1. The presence of the proper quantity of active yeast, and its proper distribution through the worts. If in the course of a slack fermentation the yeast subsides lo the bottom, the intestine motions cease entirely, but they may be excited anew by stirring up the ingredients, or rousing the tun, as Ihe brew- ers say. 2. A certain degree of warmth, which should never be less than 51° F., nor more than 86° j the temperature of from 68° lo 77° being the most propitious for the FERMENTATION. 697 commencement and progress of fermentation. "When other circumstances are the same^ the rapidity of the fermentation is proportional to the temperature within certain limits, 80 that, by lowering it, the action may be moderated at pleasure. 3. The fer- mentation proceeds the better and more equably the greater tl>e mass of fermenting liquor, probably on account of the uniformly high temperature, as well as the uniform distribution of the active particles of the yeast by the greater energy of the intestine movements. 4. The saccharine solution must be sufficiently diluted with water; when too much concentrated it will not ferment Hence very sweet musts furnish wines containing much undecomposed sugar. For a complete fermentative action, one part of sugar should be dissolved in ten parts of water. Fermentation maybe tempered or stopped: 1. by those means which render the yeast inoperative, particularly by the oils that contain sulphur, as oil of mustard ; as also by the sulphurous and sulphuric acids. The operation of the sulphurous acid in obstructing the fermentation of must consists partly, no doubt, in its absorbing oxygen, whereby the elimination of the yeasty particles is prevented. The sulphurous acid, moreover, acts more powerfully upon fermenting liquors that contain tartar, as grape juice, than sulphuric acid. This acid decomposes the tartaric salts, and combining with their bases, sets the vegetable acid free, which does not interfere with the fermen- tation; but the sulphurous acid operates directly upon the yeast: 2, by the separation of the yeast, either with the filter or by subsidence ; 3, by lowering the temperature to 45*^ F. If the fermenting mass become clear at this temperature, and be drawn off from the subsided yeast, it will not ferment again, though it should be heated to the proper pitch. The products of vinous fermentation are carbonic acid gas, and alcohol; of whidi the former escapes during the process, except in the case of the sparkling wines, like cham- paign, that are partially fermented in close vessels. The alcohol remains in the ferment- ed liquor. 100 parts of sugar afford by complete decomposition nearly 50 parts of alco- hol. According to Thenard, 100 parts of sugar are converted into 46*8 parts of carbonic acid, and 49-38 of alcohol ; besides 3*82 parts of carbon otherwise employed, which the sugar contained, above what is present in the former two products. This chemist found in the fermented liquor 4 per cent, of an extractive matter, soluble in water, and having an acidulous reaction, to whose formation, probably, that excess of carbon may be neces- sary. In what way the action of the yeasty particles upon the saccharine substance is carried on in the vinous fermentation, or what may be the interior working of this pro- cess, is not accurately understood. The quantitative relation of the carbonic acid and alcohol to the sugar is pretty well made out ; but the determination of the ultimate prin- ciples of the ferment itself, before and after the vinous change, and of the residuum dis- solved in the fermented liquor, has not been well ascertained. It is probable that the yeast undergoes in the process a similar decomposition to that of the putrefactive, and that its elementary constituents enter into new combinations, and abstract so much carbon and hydrogen from the sugar, that the remainder, amounting to 96 per cent, of the whole, may constitute one atom of alcohol and one of carbonic acid. 3. The slimy or glutinous fermentation. — This process takes place in weak solutions of sugar, at ordinary fermenting temperatures, where, from defect of good yeast, the vinous fermentation cannot proceed. In such circiimstances, from one part of sugar, one third part of gum is formed. According to Desfosses, however, 100 parts of sugar afford 109-48 of cum or slime. This is formed when one part of sugar is dissolved in twenty parts of water, which had been previously boiled with washed barm or gluten, and then filtered. The process proceeds slowly and quietly, equally well in close vessels, as with contact of air, and continues at ordinary temperatures about 12 days ; but it goes on more rapidly and completely at the heat of from 77° to 86° F. A small quantity of hydrogen and carbonic acid gas is disengaged, in the proportion of two to one by volume. The fermented liquor becomes turbid, and assumes a tough thready appearance, like a decoc- tion of linseed. A small addition of sulphuric or sulphurous acid, of muriatic acid and alum, or of tannin, impedes this species of fermentation ; because these substances com- bine, as in the vinous fermentation, with the ferment into an insoluble precipitate, unsus- ceptible of further change. In many wines, especially when bottled, this slimy fermenta- tion occurs, and occasions their ropiness, which may be best remedied or prevented by the addition of as much tannin as will precipitate the dissolved mucous matter. This species of fermentation attacks very rapidly the rinsing waters of the sugar refiner, which always contain some fermentative gluten. A little alum is the best preventive in this case, because it precipitates the dissolved ferment. 4. Tii£ acetous or sour fermentation. — In this process, alcohol, more or less dilute, is resolved into water and vinegar in consequence of the operation of the ferment j oxy- ; • I I 698 FERMENTATION. dizement of the alcohol being effected by the oxygen of the atmospherical air. Tlie requisites of this process have been already detailed under the article Acktic Acid. They are the presence of atmospherical air ; alcohol diluted to a certain degree with water ferment or yeast, and a temperature above 66° F. The most active ferments are such substances as have already passed into the acetous state; hence vinegar, especially when it contains some yeasty particles, or is combined with porous and spongy bodies, so as to multiply its points of contact with the vinous liquor, is particularly powerful. Common yeasl may also be employed for vinegar ferments, if it be imbued with a little vinegar, with leaven, crusts of bread soaked in vinegar, the stalks and husks of grapes, sawdust and shavings of beech or oak impregnated with vinegar, or the slimy sediment of vinegar casks called mother ; all of which operate as ferments chiefly in consequence of the vinegar which they contain. The inside shavings of the staves of vinegar tuns act on the same principle. The acetous fermentation may, r:oreover, go on along with the vinous in the same liquor, when this contains sugar as well as alcohol. Whilst the acidification of the alcohol is effected by the absorption of oxygen from the atmosphere, the sugar becomes alcohol with disengagement of carbonic acid, and then passes into vinegar. Since most liquors intended for making vinegar, such as wine, juices of fruits, ales, &c., contain still a little sugar, they disengage always a little carbonic acid. Besides spirits, some other substan- ces, such as gum, the mucilage of plants, and starch paste, directly ferment into vinegar. Sugar also seems to be convertible into vinegar without any vinous change. The albu- minous matter of potato juice, precipitated by vinegar, serves as a proper ferment for that purpose, when added in its moist state to weak sirup. 5. See Putrefaction. Mr. William Black, in his treatise on Brewing, has, with much ingenuity and apparent truth, endeavored to show that the process of fermentation is strongly influenced by electricity, not only that of the atmosphere, as has been long known from the circumstance if beer and wine becoming speedily sour after thunderstorms, but the voltaic, produced by electric combinations of metals in the fermenting tuns. He therefore recom- mends these tuns to be made with as little metallic work as possible, and to be insulated from the floor of the brewhouse. For the propriety of this advice he adduces some striking examples. Wort which had become stationary in its fermentation, on being pumped out of square gyles imbedded in the floor, into casks placed upon wooden stillions, began immediately to work very well, and gained about 6 degrees of^ attenuation while throwing off its yeast. From the stagnation of the process in the gyles, he had in the morning predicted an approaching thunderstorm, which accordingly supervened in the course of the evening. In further support of his views he instances the fact, that, in dairies where the milk is put into porcelain vessels, and placed upon wooden shelves, it is seldom injured By lightning; but when contained in wooden or leaden vessels, and placed upon the ground, it almost invariably turns sour in thunder} weather. His general conclusion i?, " that the preservation or destruction of beer depends upon elec- tricity ; and the most certain mode of preservation is to insulate as much as possible, both the squares and all other utensils or vessels connected with the brewing or storing of beer." Mr. Black further considers that unsoundness of worts is often the result of electricity excited between the mash tun and the copper. Why is beer liable to get spoiled in thunder-storms, though apparently well insulated in glass bottles ? I shall conclude this article with Mr. Black's description of the phenomena of beer fermentation. In every regular process there are five distinct stages. In the first we see a substance like cream forming all round the edges of the gyle tun ; which ex- tends towards the centre until the whole is creamed over, constituting the first change. Next a fine curl appears like cauliflower, which also spreads over the square surfacs, and according to the strength and appearance of this curl, the quality of the fermenta- tion may be predicated. This he calls the second stage. What is technically called the stomach or vinous vapor now begins to be smelt, and continues to gain strength till the process is concluded. From the vinous energy of this odor, and the progressive attenuation of the wort, the vigor of the fermentation may be inferred. The experienced brewer is much guided in his operations by the peculiarity of this effluvium. The third change is when the cauliflower or curling top rises to a fine rocky or light yeasty head; and when this falls down, the fourth stage has arrived. Finally the head should rise to what is called close yeastv, having the appearance of yeast all over. About this period the gas becomes so powerful as to puff up occasionally in little bells or bladders about the size of a walnut, which immediately break. The bells should appear bright and clear. If they be opaque or whey colored, there is some unsoundness in the wort. The great FERMENTATION. 699 point is to add just so much yeast as to carry the fermentation completely through these five changes at the regular periods. The terra fermentation has been of late extended t^ several operations besides those formerly included under it The phenomena which it exhibits under these different phases and the changes which it eflTecte among the various subjects of its operations, are no less striking and mysterious in their principle than important in their application to the arts of life. Fermentations are now arranged into twelve classes — 1, the alcoholic; 2, the glucosic or saccharine ; 3, the viscous or mucous; 4, the lactic; 5, the ascetic ; 6, the gallic; 7, thepectic; 8, the benzoilic ; 9, the sinapic ; 10, the ammoniacal ; 11, the putrid ; and 12, the fatty. Fermentation, in the most general sense, may be defined to be a spontaneous re- action, a chemical metamorphosis, excited in a mass of organic matter by the mere presence of another substance, which neither extracts from, nor gives to, the matter which it decomposes any thing whatever. This process requires the following con- ditions: — 1. A temperature from 45° to 9(P F. ; 2. Water; 3. The contact of air; 4. The presence of a neutral organic azotized matter, in a very small quantity, and of a crystallizable non-azotized substance, in considerable quantity. Tlie former is the ferment., the latter undergoes fermentation. In ordinary chemical actions we perceive one body unite to another to form a new compound ; or one body turn another out of a combination, and take its place, in virtue of a superior aflSnity. These effects are foreseen and explained by the intervention of that molecular force which governs all chemical operations, that attractive power which unites the particles of dissimilar bodies. Thus, also, in the ordinary phenomena of decomposition, we perceive the agency of heat at one time, at another of light, or of electricity ; forces of which, though we are not acquainted with the essence, yet we know the exact effect under determi- nate circumstances. But fermentation, on the contrary, can be explained neither by the known laws of chemical affinity nor by the intervention of the powers of light, elec- tricity, or heat. Fermentation reduces complex organic substances to simpler com- pounds, thereby reducing them nearer to the constitution of mineral nature. It is an operation analogous, in some respects, to that effected by animals upon their vegetable food. With a good microscope, any person :nay convince himself that ferment or yeast ii an organized matter, formed entirely of globules, or of corpuscles slightly ovoid, from the three to the four thousandth part of an inch in diameter. Sometimes their surface seems to have a little tail, which has been regarded as a bud or germ attached to the mother cell. Whenever the fermentation begins, the yeast does not remain an instant idle. These small round bodies become agitated in all directions, and if the substance undergoing fermentation is mixed with an azotized matter, as in beer-worts, the cor- puscles become larger, the small tails get developed, and on acquiring a certain size they separate from the parent globule, to live by themselves and give birth to new cor- puscles.* In the fermentation of beer from malt, this series of multiplications produces a quantity of yeast seven times greater than what was added at the commencement. Were the above ingenious speculations demonstrated with certainty, we should be led to admit, in all these phenomena, actions truly vital, and a reproduction like that of buds in the vegetable kingdom. The existence of a vital force seems to be rendered probable by the fact that in incomplete fermentation, such as that of fine syrup with too little yeast, the ferment loses its properties and powers. If, however, we add to the so- lution of pure sugar an albuminous substance, a caseous or fleshy matter, the devel- opment of yeast becomes manifest, and an additional quantity of it is found at the end of the operation. Thus with nourishment, ferment engenders ferment. It is for this reason that a little fermenting must, added to a body of^ fresh grape-juice, excites fer- mentation in the whole mass. These effects are not confined to alcoholic fermentation. The smallest portions of sour milk, of sour dough, or sour juice of beet-root, of putrefied flesh or blood, occasion like alterations in fresh milk, dough, juice of beet-roots, flesh, and blood. But further, and which is a very curious circumstance, if we put into a li- quid containing any fermenting substance, another in a sound state, the latter would Bufl'er decomposition under the influence of^ the former. If we place urea in presence of beer-yeast, it experiences no change ; while if we add to it sugar-water in a ferment- ing state, the urea is converted into carbonate of ammonia. We thus possess two modes of decomposition, the one direct, the other indirect. Although yeast has all the appearances of an organized substance, it is merely by anal- ogy that its multiplication by growth is assumed, for this is a phenomenon very difficult of experimental demonstration. When blood, cerebral substance, gall, pus, and such like substances, in a putrid state, are laid upon fresh wounds in animals, vomiting, de- * M. Turpin, M. Cagniard Latour, M. Qu€venne, and Professor Mitscherlich. \* 700 FERMENTATION. II debility, and death soon anpervene. The scratches from bones in putrid bodies have been often the causes of disease and death to anatomists The poison in bad sausages is of the same class of ferments. In "Wurtemberg, where sausages are prepared from very miscellaneous matters, as blood, livers, brains, and offal of many other kinds, with bread, meal, salt, and spices, fatal results from eating them are not uncommon. Death in these cases is preceded by the gradual wasting of the muscular fibre, and of all the like constituents of the human body ; so that the patient becomes emaciated, dries into a complete mummy, and soon expires. The cadaver is stiff as if frozen, and is not subject to putrefaction. During the progress of the satisage disease, the saliva becomes viscid, and emits an offensive smell. No peculiar poison can be detected by analysis in the sausages ; but they are rendered wholesome food for animals by the action of alcohol, or by that of boiling water, which destroy the noxious /owej» without acquiring it themselves; and thus decompose the putrefactive ferment of the sausages. When this, however, passes unchanged through the stomach into the circulating system, it imparts its peculiar action to the constituents of the blood, operating upon it as yeast does upon wort Poisons of a like kind are produced by the body itself in some diseases. In piague, small-pox, measles, ful power when subjected to the action of the stomach ; whereas that of bad sausages, which is acid, resists the modifying power of the digestive organs. Alcoholic fermentation has been copiously discussed in the Dictionary. I may here add that ammonia, being a product of that change in solution of pure sugar, proves the presence of azote in the yeast ; and that sulphuretted hydrogen, being made manifest in the disengaged gaseous products, by their blackening paper imbued with acetate of lead, proves the presence of sulphur. The acid liquor accompanying yeast may be washed away, without impairing materially its fermenting power, while the acid so removed has of itself no such virtue. Yeast, freed from all soluble matters by water, alcohol, and ether, contains, indepen- dently of ashes — carbon, 50*6 ; hydrogen, 7-3 ; azote, 15; oxygen, sulphur, and phospho- rous, 27' 1, in 100 parts. Viewed atomically, yeast bears a close analogy to albumen. Like albuminous matter, yeast takes a violet tint with muriatic acid, and it may be re- placed as ferment by gluten. Caseum (the curd of milk) and flesh operate the same effect. All these fermentative powers have the same globular appearance in the mi- croscope with yeast. When the activity of yeast has been destroyed by heat, &c., it can be restored by the positive energy of the voltaic battery, which causes its combina- tion with oxygen. The best proportion of sugar and water, for exhibiting the phenom- ena of fermentation, is 1 of the former to 3 or 4 of the latter, and 5 parts of sugar to 1 of fresh yeast may be added ; though in the course of fermentation, 100 parts of sugar do not consume 2 parts of yeast, estimated in the dry state. The quickest fermenting temperature is from 68^ to 86°. A very little oil of turpentine or creosote, or of the mineral acids, prevents or stops fermentation completely ; oxalic and prussic acids have the same effect, as also corrosive sublimate and verdigris. It has been known from time immemorial in Burgundy, that a little red precipitate of mercury, when added to the must-tun, stopped the fermentation. All alkalies counteract fermentation, but when they are saturated it recommences. The first person who described the microscopic globules of yeast with precision was Desmazieres, who arranged them among the my- codermes (fungus-skinned), under the name of mycoderma cerevisia. They have not the flattened form of the globules of blood, but are rather egg-shaped. One small black point may be seen on their surface, which, after some days, is associated with 3, 4, or 5 others. Their average diameter is from _-J — to — I of an inch. Sometimes more 5000 4000 minute globules cluster round one of ordinary size, and whirl about with it, when the liquor in which the globules float is agitated. Fresh yeast loses, by drying, 68 parts in the 100, and becomes solid, horny-looking, and semitransparent, breaking readily into gray or reddish fragments. With water, it resumes immediately its pristine appearance. When fresh yeast is triturated with itf own weight of white sugar, it forms a liquid possessing the fluidity of oil of almonds and a yellow color. The globules continue unchanged, except perhaps becoming FERMENTATION. 701 eomewhat smaller. Yeast in the dry state retains its fermentative virtue for a long time. Saccharine Fermentation is that by which starch and dextrine are converted into sugar, as shown remarkably in the action of diastase upon these bodies. If we mix 2 parts of starch paste with 1 part of dry gluten, and keep the mixture at a temperature of from 122° to 140° Fahr., we obtain a good deal of sugar and dextrine. Some lactic acid is also formed. Flour paste, long kept, spontaneously produces sugar by a like reaction. See Fermentation in the Dictionary. Lactic Fermentatim. — Almost all azotized organic matters, after being modified by the contact of air, become capable of giving rise to this fermentation. Oxygen docs not come into play, except as the means of transforming the animal substances into a ferment. Diastase and caseum are well adapted to exhibit this change. The body that is to furnish the lactic acid may be any one of the neutral vegetable matters, pos- sessing a like composition with lactic acid, such as cane-sugar, grape or potato sugar, dextrine, and sugar of milk. All the agents which stop the alcoholic, stop also the lactic fei-mentation ; while diastase and caseum are its two best exciters. For produ- cing abundance of lactic acid, we have merely to moisten malt, to expose it to the air for a few days, then to triturate it with a quantity of water, and leave the emulsion for some days more in the air, at a temperature between 67° and 86° F. We then saturate the liquor with chalk, afler having filtered it, and thereby obtain the lactate of lime which may be crystallized in alcohol, to deprive it of the dextrine and earthy phosphates ; and then decomposed by sulphuric acid. Lactic jlcid, formed from curd (caseum), exhibits more remarkable phenomena. Tims whfn milk is lefl alone for some time it becomes sour, and coagulates. The coagulum e formed of caseum and butter ; while the whey of it contains sugar of milk and some •alts. The coagulation of the caseum has been occasioned by the lactic acid, which was generated in consequence of an action which the caseum itself exercised upon thf sugar of milk. Thus with the concourse of air, the caseum becomes a ferment, and excites the conversion of the sugar of milk into lactic acid. The lactic acid in its turn coagulates the caseum, which in the consolidation of its particles attracts the butter. The caseum then ceases to act upon the sugar of milk, and consequently produces no more lactic acid. But now, if the lactic acid already formed be saturated, the caseum will redissolve, and the phenomena will recommence in the same order. This is easily done by adding a due dose of bicarbonate of soda to the soured milk. In the course of 30 hours a fresh portion of lactic acid will be generated, and will have coagulated the milk again. We may also add some sugar of milk to the liquid, and to a certain extent convert it into lactic acid. Milk boiled, and kept from contact of air, will not coagulate, and remains fresh for many months. Animal membranes, modified by exposure to moist air for some time, form a true ferment for the lactic fermentation, and acidify solutions of sugar, dextrine, and gum, but the membranes must not be putrescent. Cane-sugar, starch-sugar, and sugar of milk, by assuming or losing a little w.iter, acquire the con- stitution of lactic acid. Viscous or Mucous Fermentation. — Every one is acquainted with this spontaneous modification of white wine and ale, which gives them a stringy or oily aspect, and is called in French graisse, or fat of wines, and in English the ropiness of beer. The viscous fermentation may be excited by boiling yeast with water, and dissolving sugar in the decoction, after it has been filtered. The syrup should have a specific gravity from 1*040 to 1'055, and be kept in a warm place. It soon assumes the consistence and aspect of a thick mucilage, like linseed tea, with the disengagement of a little car- bonic acid and hydrogen, in the proportion of 2 or 3 of the former gas to 1 of the latter. A ferment of globular texture like that of yeast is formed, which is capable of producing viscous fermentation in any saccharine solution to which it is added, pro- vided the temperature be suitable. The viscid matter being evaporated to dryness forms transparent plates, of a sub-nauseous taste, and soluble in water, but less easily than gum arabic. Its mucilage is, however, thicker than that of gum, and yields with nitric acid, oxalic acid, but no mucic acid. Four parts of sugar, treated as above described, furnish 2*84 of unchanged sugar, and 1*27 of the mucilage; from which it appears that water becomes fixed in the transformation. Muriatic, sulphuric, sulphur- ous acids, and alum, prevent the production of the viscous fermentation, by precipitating its ferment. It is probably the soluble portion of gluten which is the cause of this spe- cies of fermentation. It has been found, accordingly, that tannin, which precipitates the said glutinous ferment, completely stops the viscous fermentation, or graisse, of wines. It is owing to the tannin which the red wines derive from the grape-stalks, with which they are long in contact during fermentation, that they are preserved from this malady of the white"* wines. The gluten of must is of two kinds the one soluble in virtue of 702 FERMENTATION. FERMENTATION. 703 ^ the alcohol and tartaric acid, and producing the viscous, the other insoluble, and producing the alcoholic fermentation. The art of the wine maker consists in precipi- tating the injurious ferment, without impeding the action of the beneficial one: an art of considerable delicacy with regard to sparkling wines. Add Fermentation h^s been fully discussed under acetic acid. It requires the pre^ cnce of ready formed alcohol and air. The lactic fermentation, on the contrary, may take place with starchy or saccharine substances, without the intervention of alcohol or constant exposure to the atmosphere ; and when once begun, it can go on without air. Acetification has a striking analogy with nitrification, as is shown by the necessity of a sil?face°trth '"^' ^ ^"""""^ ^"^^^^ ^""^ exposing the liquid on a great Benzoic Fermentatim is that which transforms the azotised neutral crystalline matter existing in bitter almonds, which has no action upon the animal economy, into new and remarkable products, among others the hydrure of benzoile and hydrocyanic (prussic) acid, which together constitute the liquid, called oil, or essence, of bitter almonds, a compound possessed of volatility and poisonous qualities. The attentive study of this Hn'.Tn hvl ' ''7^^!? ^ great fact in vegetable physiology, the spontaneous pro- duct on by means of certain artifices, of certain volatile oils, not pre-existing in the plants, yet capable of being generated in the products of their decomposition. The volatile Oil of bitter almonds constitutes in this respect a starting point, from which drJnrr'^rl'^" °'^ of mustard, the oil of spir^a, and which wiU hkely'lead toX5 discoveries of the same kmd. See Almond and Amygdaline Sinapic Fermentation is that by which the oil of mustard is'formed, and which takes place by the contact of water, under certain conditions, of too refined and scientific a nature for this practical work. PecticFermeniati(m.—Veciic acid may be obtained from the expressed luice of cai rots, and it seems to be formed in the process of extraction by the reaction of albumine !?-n?"?\"P^''^^,"^'*^"'=^ called pectine ; a transformation analogous therefore with that which takes place in the formation of the essence of bitter almonds. Gallic Fermentation.— GaUic acid does not exist ready formed in nut-galls, but la generated from their tannin when ihey are ground, made pasty with water, and exposed to the air. This conversion may be counteracted by the red oxide of mercury, alcohol, suJphuric, muriatic, and nitric acids, bromine, essence of turpentine, creosote, oxalic acetic, and prussic acids. The tannin disappears in the sequel of the above metamor' pnosis. Fatty Fermentation.— All fats are transformed by the action of an alkaline or other base into certain acids, the stearic, margaric, the oleic, ethalic, &c. When these acids are once foiled, they can not by any means, hitherto known, be reconverted into the prim- itive tat. By the fixation of water in the acid and the base (called glycerine), a chan-e is effected which can not be undone, because the glyceric base is incapable by itself to displace the water, once combined in the hydrated fat acid. The circumstances neces- sary to the fluty fermentation, are like those of other fermentations; namely the co- operation of an albuminoid matter, along with water, and a temperature of from 60° to S&* J? . ; under these conditions, the matter becomes warm, and assumes speedily the charac ter of rancidity; acid is generated, and the carbonate of soda can then form salts, while the fatty acid is hberated; a circumstance impossible when the fat was vz-ted upon in the neutral state. This altered fat, treated with water, gives up to ii g/vaWc alcohol. Digestive iemen/aiton.— Digestion of food maybe considered in its essential features as a peculiar fermentative process. The gastric juice is a genuine ferment. Tiedmann ^melin and Prout, have shown that the gastric juice contains muriatic acid ; and li-berli has made interesting experiments on the digestion of food out of the body with water containing a few drops of the same acid. He observed that when this liquid con tamed none of; the mucous secretion of the stomach, it did not dissolve the aliments put into It; but with a little of that mucus it acquired that property in an eminent degree li-ven the mucus of the bladder had a like eflect. Schwann and Vogel have produced this digestive principle in a pure state, called by them pepsine, as obtained most abun- dantly from the stomachs of swine. The glandular part of that viscus being separated from the serous, is cut into small pieces, and washed with cold distilled water. After digestion for 24 hours, that water is poured off, and fresh water is poured on. This operation IS repeated for several days, till a putrid odor begins to be felt. The watery infusion thMs obtained is precipitated by acetate of lead, this white flaky precipitate contains the ptpsine, accompanied with much albumen. It is then washed, mixed with wate, , and subjected to a stream of sulphuretted hydrogen. The whole being now thrown on a filter, the coagulated albumen remains on the paper, along with the sul. phuret of lead, while the pepsine liquor passes, associated with some acetic acid. If to this liquor a very small quantity of muriatic acid be added, it becomes capable of carry- ing on artificial digestion. Dry pepsine may be obtained by evaporating the above filtered liquor on a water bath, to a syrupy consistence, then adding to it absolute alcohol, which causes a bulky whitish precipitate. This dried in the air constitutes pepsine. It contains a minute quantity of acetic acid, which may be removed com- pletely, by heating it some hours on the water bath. The white powder then obtained is soluble in water, and betrays the presence of no acid whatever. According to Vogel, this substance is composed of, carbon, 57' 72 ; hydrogen, 5*67 ; azote, 21-09; oxygen, &c., 15.52 = 100. Vogel has proved the analogy between the action of pepsine and diastase by the following experiment : — He dissolved two grains of pepsine in very weak muriatic acid, and put into this liquor heated to 81° F., small bits of boiled beef. In the course of a few hours the pieces became transparent on their edges, and not long after they were completely dis- solved. He now added fresh morsels in succession, till those last put in remained un- changed. He found by analysis, that 1*98 grains of the pepsine were left, showing how minute a portion of this ferment was necessary to establish and effect digestion. In fact, we may infer that pepsine, like yeast, serves to accomplish digestion without any waste of its own substance whatever, or probably with its multiplication. Rennet, with which milk is coagulated in making cheese, is somewhat of the same nature as pepsine. It has been called chymosine. But the simplest digesting liquor is the following : — If 10,000 parts of water by weight be mixed with 6 parts of ordinary muriatic acid and a little rennet, a liquor is obtained capable of dissolving hard boiled white of egg, beef, gluten, &c., into a transparent jelly in a feW hours. Ammoniacal Fermentation. — Under this title may be described the conversion of urea into carbonate of ammonia under the influence of water, a ferment, and a favorable temperature. Urea is composed in atoms ; reckoned In volumes, Carbon 4 ; hydrogen 8 ; azote 4 ; oxygen 2 ; which by fixing — 4 ; — 2 ; give 4; 12; 4; 4: which is 4 vol. of carbonic acid, and 8 of ammonia; equivalent to ordinary carbonate of ammonia. The fermentation of urea plays an important part in the reciprocal offices of vegetable and animal existence. By its conversion into carbonate of ammonia, urea beconies a food fit for plants ; and by the intervention of the mucous ferment which urine contain^, that conversion is effected. Thus the urea constitutes a neutral and innocu- ous substance while it remains in the bladder, but is changed into a volatile, alkaline, and acrid substance, when it is acted upon by the air. Yeast added to pure urea mixed with water, exercises no action on it in the course of several days ; but when added to urine, it soon causes decomposition, with the formation of carbonate of ammonia, and disengagement of carbonic acid. The deposite on chamberpots ill-cleaned acts as a very powerful ferment on urine, causing the complete decomposition of fresh urine in one fifth of the time that would otherwise be requisite. Nitrous Fermentation, as exhibited in the formation of nitric acid from the atmosphere, and consequent production of nitrates in certain soils, has been with much probability traced to the action of ammonia on oxygen, as the interiredium or ferment. Caseous and putrid Fermentations. — Curd is convertea into cheese, when after being coagulated by rev.net, it is left to itself under certain conditions; and this constitutes the true distinctive character of caseum. In the production of cheese there is evidently the intervention of a peculiar ferment which is gradually formed, and the decomposition ol the curd into new products. For animal and vegetable matters to run into putrefaction, they must be in contact with air and water, at a certain temperature ; viz., between the freezing and boiling points of water. The contact of a putrid substance acts as a ferment to fresh animal and vegetable matters. The reagents which counteract fermentation in general stop also putrefaction. In this process, myriads of microscopic animalcules make their ap- pearance, and contribute to the destruction of the substances. A dispute haying taken place between some distillers in Ireland and officers of Excise, concerning the formation of alcohol in the vats or tuns by spontaneous fermen. tation, without the presence of yeast, the Commissioners of Excise thought fit to cause a series of experiments to be made upon the subject, and they were placed under my general superintendence. An experiment was made on the 6th of October, with the following mixture of corn : — 45 704 FERMENTATION. FERMENTATION. Mi t 2 Bushels of Barley, weighing I Bushel of Malt, j^ Bushel of Oats - lOOlbs. 5 07. -21 7 - 20 12 Total, 3 Bushels, weighing - 142 8 The bruised corn was wetted with 26 gallons of water at the temperature of 160° F., and, after proper stirring, had 8 gallons more of water added to it at the average tem- perature of 194^. The mash was again well stirred, and at the end of 45 minutes the whole was covered up, having at that time a temperature of 138° F. Three hours afterward, 16 gallons of wash only were drawn off; being considerably less than should have been obtained, had the apparatus been constructed somewhat differently, as shall be presently pointed out. The gravity of that wash was 1*060, or, in the lan- guage of the distiller, 60^. After a delay of two hours more, twenty additicnal gallons of water at the temperature of 200° were introduced, when the mash was well stirred, and then covered up for two hours, at which period 23 gallons of fine worts of specific gravity 1-042 were drawn off. An hour afterward 12 gallons of water at 200° were added to the residual grains, and in an hour and a half 11 gallons of wort of the density 1*033 were obtained. N^xt morning the several worts were collected in a new mash tun. They consisted of 48 gallons at the temperature 80°, and of a specific gravity 2-0465 when reduced to 60°. Being set at 80°, fermentation soon commenced; in two days the specific gravity had fallen to 1*0317, in three days to 1*018, in four days to 1-013, and in five days to 1.012, the temperature having at last fallen to 78* F. The total attenuation was therefore 34|°, indicating the production of 3-31 gallons of proof spirit, while the produce by distillation in low wines was 3-22; and by rectification in spirits and feints it was 3-05. The next experiment was com- menced on the 12th of October, upon a similar mixture of corn to the preceding. 48 gallons of worts of 1-043 specific gravity were set at 82° in the tun, which next day was attenuated to 1-0418, in two days to 1-0202, in three days to 1-0125, and in five days to 1*0105, constituting in the whole an attenuation of 32|°, which indicates the production of 3*12 gallons of proof spirits ; while the produce of the first distiUk tion was 2-93 in low wines, and that of the second in feints and spirits was 2*66. Ii these experiments the wash, when fermenting most actively, seemed to simmer and boil on the surface, with the emission of a hissing noise, and the copious evolution of car- bonic acid gas. They prove beyond all doubt that much alcohol may be generated in grain worts without the addition of yeast, and that, also, at an early period; but the fermentation is never so active as with yeast, nor does it continue so long, or proceed to nearly the same degree of attenuation. I was never satisfied with the construction of the mash tun used in these experiments, and had accordingly suggested another form, by which the mash mixture could be maintained at the proper temperature during the mashing period. It is known to chemists that the diastase of malt is the true saccharifying ferment which converts the fecula, or starch of barley and other corn, into sugar ; but it acts beneficially only between the temperatures of 145° and 168° F. When the temperature falls below the former number, saccharification lan- guishes ; and when it rises much above the latter, it is entirely checked. The new mash tun was made of sheet zinc, somewhat wider at bottom than top; it was placed in a wooden tun, so much larger as to leave an interstitial space between the two of a couple of inches at the sides and bottom. Through this space a current of water at 160° was made to circulate slowly during the mashing period. Three bushels of malt, weighing 125 lbs. 3 oz., were wetted with 30 gallons of water at 167°, and the mixture being well agitated, the mash was left covered up at a temperature of 140° during three hours, when 19 gallons of fine worts were drawn off at the spe- cific gravity of 1-0902 or 90-2°. Twenty gallons more water at 167° were then added to the residuum, which afforded after two hours 28 gallons of wort at the gravity 1*036; 12 gallons of water at 167° were now poured on, which yielded after other two hours 15 gallons at the gravity 1-0185. Forty gallons of fine worts at 1-058 gravity and 68"^ temperature were collected in the evening of the same day, and let into the tun with 5 per cent, of yeast. The attenuation amounted in six days to 54°. The third wort of this brewing, amounting to 15 gallons, being very feeble, was mixed with 7 gallons of the first and second worts, put into a copper, arid concentrated by boiling to 11 gallons, which had a gravity 1*058 at 60° F. They were separately fermented with 5 per cent, of yeast, and suffered an attenuation of 48|°. The produce of spirit from both indicated by the attenuation was 5*36 gallons ; the produce in low wines was actually 5-52, and that in spirits and feints was 5-33, being a perfect accord- ance with the Excise tables. The next experiments were made with a view of determining at what elevation of temperature the activity or efficiency of yeast would be paralysed, and how far the 705 attenuation of worts could be pushed witliin six hours, which is the time limited by law for worts to be collected into the tun, from the time of beginning to run from the coolers. When worts of the gravity 1*0898 were set at 96° Fahr., with 5 per cent of • yeast, they attenuated 26*9°, m 6 hours ; worts of 1*0535 gravity set at 1 10° with 5 per cent, of yeast, attenuated 16^ in about 5 hours; but when worts of 1-0533 were set, as above, at 120°, they neither fermented then, nor when allowed to cool ; show- ing that the activity of the yeast was destroyed. When fresh yeast was now added to the last portion of worts, the attenuation became 5*8 in 2 hours, and 28*4° in 3 days * showing that the saccharine matter of the worts still retained its fermentative faculty' Malt worts, being brewed as above specified, were set in the tun, one portion at a tem- perature of 70°, with a gravity of 1*0939, and 5 per cent, of yeast, which attenuated 66° in 3 days ; other two portions of the same gravity were set at 120° with about 10 per cent, of yeast, which underwent no fermentative change or attenuation in 6 hours, all the yeast having fallen to the bottom of the tuns. When these two samples of worts were allowed, however, to cool to from 74° to 72°, fermentation commenced, and produced m two days an attenuation of about 79°. It would appear, from these last two experiments, that yeast to the amount of 5 per cent, is so powerfully affected by strong worts heated to 120° as to have its fermentative energy destroyed; but that when yeast is added to the amount of 10 per cent., the 5 parts of excess are not per- manently decomposed, but have their activity merely suspended till the saccharine liquid falls to a temperature compatible with fermentation. Yeast, according to my observations, when viewed in a good acromatic microscope, consists altogether of trans- lucent spherical and spheroidal particles, each of about the 6000th part of an inch in diameter. When the beer in which they float is washed away with a little water they are seen to be colorless; their yellowish tint, when they are examined directh' from the fermenting square or round of a porter brewery, being due to the infusion of the brown malt. The yeast of a square newly set seems to consist of particles smaller than those of older yeast, but the difference of size is not considerable. The re- searches of Schulze, Cagniard de la Tour, and Schwann, appear to show, that the vinous fermentation, and the putrefaction of animal matters, processes which have been hitherto considered as belonging entirely to the domain ol chemical affinity—are essentially the results of an organic development of living beings. This position seems to be established by the following experiments: 1. A matrLs or flask con- taining a few bits of flesh, being filled up to one third of its capacity with water, wa« closed with a cork, into which two slender glass tubes were cemented air-ti?ht. Both of these tubes were passed externally through a metallic bath, kept constantly melted, at a temperature approachmg to that of boiling mercury. The end of one of the Tu!V. 7^rS»«^^? ^'om the bath, was placed in communication with a jjasometer. in it Td t"hP ^[ ^^^"^t'^^s^ ^^•■e now made to boil briskly, so that the air^contained n?,rrnn. r t " f ^•"^^' '''"' ^^1^"^^* The matrass being then allowed to cool, a tpr^h;?t "''''' l^n-^l'"'^ "^^^ T'^^ constantly to pass through it from the gasome- ter ^lhlle the metallic bath was kept constantly hot enough to decompose the livino particles m the air. In these experiments, which were many times repeated, no infu^ soria or fungi appeared, no putrefaction took place, the flesh underwent no chan-e and the liquor remained as clear as it was immediately after beine boiled. As it wa^* found very troublesome to maintain the metallic bath at the meltfng pitch, the foHow- mg mod.ficaiion of the apparatus was adopted in the subsequent researches : A flalk of three ounces capacity, being one fourth filled with water and flesh, was closed with cnri' .1''° ' ^^cT'^ '" Its place by wire. Two glass tubes were pass.^d through the cork; the one of them was bent down, and dipped at its end into a small capsule con- taining quicksilver, covered with a layer of oil ; the other was bent on leaving, the cork, lirst into a horizontal direction, and downward for an inch and a half afterward no nf^ P^i: *>f «P"-^I J"r"s> then upward, lastly horizontal, whence it was drawn out to. K; fl ^^ pores of the cork having been filled with caoutchouc varnish, the contents thin .^f V"""^ boiled till steam issued copiously through both of the glass tubes, and fir^n M r ^"^ °' ^."'^T ^' ^^' ^' ^^"^'^^ ^^^*^^- ^'^ «rder that no living par- ticles could be generated in the water condensed beneath the oil, a few fragments of eorrosive sublimate were laid upon the quicksilver. During the boiling, the flame of a spirit lamp was drawn up over the spiral part of the second glass tube^by means of a glass chimney placed over it, so as to soften the slass, while the further part of the tube was heated by another spirit lamp, to prevent its getting cracked by the condens- ation of the steam. After the ebullition had been kept up a quarter of an hour, the ♦ K "^WK Tk ^"^ ''°*''' ^""^ '^^ ^"^^ ^'^h air through the hot spiral of the second lube. When the contents were quite cold, the end of this tube was hermetically sealed, the part of it between the point and the spiral was heated strongly with the names, and the lamps were then withdrawn. The matrass contained now nothing but 706 FERRIC ACID. m boiled flesh and gently ignited air. The air was renewed occasionallj through the second tube, its spiral part being first strongly lieated, its point then broken oflF, and connected with a gasometer, which caused the air to pass onward slowly, and escape at the end of the first tube immersed in the quicksilver. The end of the second tube was a?ain hermetically closed, while the part interjacent between it and the spiral was exposeil to the spirit flame. By means of these precautions, decoctions of flesh were preserved, during a period of six weeks, in a temperature of from 14^ to 20^ R. (oSg to 77^ F.), without any appearance of putrefaction, infusoria, or mouldiness : on open- ing the vessel, however, the contents fermented in a few days, as if the, had beea boiled in the ordinary manner. In conducting such researches, the greatest pams must be taken to render the cork and junctions of the glass tubes perfectly air-tight. The following more convenient modification of the experiment, but one equally suc- cessful and demonstrative, was arranged by F. Schulze. The glass tubes connected with the flask were furnished each with a bulb at a little distance from the cork ; into one of which globes caustic alkaline ley being put, and into the other strong sul- phuric acid, air was slowly sucked through the exiremity of the one lube, while it entered at the other, so as to renew the atmosphere over the decoction of flesh in the flask. In another set of experiments, four flasks being filh I with a solution of cane- sugar containing some beer-yeast, were corked and plunged m boiling water till they acquired its temperature. They were then taken out, inverted in a mercurial bath, uncorked, and allowed to cool in that position. From one third to one fourth of then volume of atmospherical air was now introduced into each of the flasks; into two of them through slender glass tubes kept red hot at a certain point, into the other two through glass tubes not heated. Bv analysis it was found that the air thus heated contafned only 19-4 per cent, of oxygen, instead of 20-8; but, to compensate ior this deficiency, a little more air was admitted into the two flasks connected with the heatea tubes than into the two others. The flasks were now corked and placed in an in- verted position, in a temperature of from 10^ to 14- R. (541^^ to 63|-" F.). After a period of from four to six weeks, it was found that fermentation had taken place m both of the flasks which contained the non-ignited air—for, in loosening the corks, Bome of the contents were proiected with force — but, in the other two flasks, there was no appear*nce of fermentation, either then, or in double the time. As the extract of nux vomica is known to be a poison to infusoria (animalcules), but not to vegetating mould, while arsenic is a poison to both, by these tests it was proved that the living particles instrumental to fermentation belonged to the order of plants of the confer- void family. Beer veast, according to Schwann, consists entirely of microscopic fungi, in the shape of small oval grains of a yellowish white color, arranged in rows oblique to each other. Fresh grapes must contain none of them ; but after being exposed to the air at 20" R., for 36 hours, similar grains become visible in the microscope, and may be observed to grow larger in the course of an hour, or even in half that time. A few hours after these plants are first perceived, gas begins to be disengaged. They multiply greatly in the course of fermentation, and at its conclusion subside to the bottom of the beer in the shape of a yellow white powder. FERRIC ACID. This new compound having been prescribes as a source of sup- plying oxygen to persons confined in diving-bells and in mines, by M. Payerne, in a patent recently granted to him, merits notice in a practical work. M. Fremy is the discoverer of this new acid, which he obtains in the state of ferrate of pot- ash, by projecting 10 parts of dry nitre in powder upon 5 parts of iron filings, ignited in a crucible ; when a reddish mass, containing much ferrate of potash, is formed. The preparation succeeds best when a large crucible, capable of holding about a pint of water, is heated so strongly that the bottom and a couple of inches above it, appear faintly, but distinctly red, in which state the heat is just adequate to eflfect due deflagration without decomposition. An intimate mixture of about 200 grains of dried nitre with about one half its weight of the finest iron filings, is to be thrown at once upon the side of the crucible. The mixture will soon swell and deflagrate. The crucible being taken from the fire, and the ignited mass being cooled, is to be taken out with an iron spoon, pounded, immediately put into a bottle, and secluded from the tir, in which it would speedily attract moisture, and be decomposed. It is resolved by ' the action of water, especially with heat, into oxygen gas, peroxide, and nitrate Mr. J. D. Smith prepares the ferrate of potash by exposing to a full red heat a mix- lure of finely powdered peroxide of iron with four times its weight of dry nitre. It has an amethyst hue, but so deep as to appear black, except at the edges. Oxygen is rapidly evolved by the action of the sulphuric or nitric acid upon its solution. He con- siders the atom of iron to exist in this compound, associated with 3 atoms of oxygen, or double the proportion of that in the red oxide. Hence 52 grains of pure ferric acid 4 I I FIBRE, VEGETABLE. 707 should give off 12 grains of oxygen, equal to about 36 cubic inches; but how much of the ferrate of potash may be requisite to produce a like quantity of oxygen cannot be stated, from the uncertainty of the operation by which it is produced FERRIC-CYANIDE OF POtIsSIUM, ^or Red Pruliate^ Potash. This beautiful and useful salt, discovered by L. Gmelin, is prepared by pissing chlorine gal through a weak solution of the prussiate of potash (ferro-cyanide of potassium) lilf k ceases to aff-ect solution of red sulphate of iron, taking care to agitate the liquid all the fTp fl^r. TJ"" HI ^° ^"""'^ ""^ '^^2"°^- ^^ ^««^^"S ^^'•^^^h the weak solution to the flame of a candle, one may see the period of change from the greenL.h to the red hue, which indicates the completion of the process. The liquor being filtered and evaporated in a dish with upright sides, will eventually aff^ord c^rstalline needles ^^ sessed of an almost metallic lustre, and a yellow color, inclining to red. These be^t dissolved and recrystallized, wil become extremely beautiful. This salt is composed of 33-68 parts of potassium, 16-48 of iron, and 47-84 of cyanogen. It is therefore a tilt of 'h n t'^-i"^'; • ^^ ^■^''' "^ '°V^ ^."*"' «"^ ^^ i* forms^hen the Lst deSc^tc test of the protoxide of iron, is very useful in Clorometry.-^See Appendix. yf2%lteZfrielllT!L'''''^ ^'^ ^^"^^"^ ^^-^^ P^-P^'tates with the soluUon. Titanium Uranium Manganese Cobalt Nickel Copper • Silver Mercury Tin Zinc Bismuth Lead Iron protoxide - peroxide - Brownish yellow. Reddish brown. Brownish gray. Deep reddish brown. Yellowish brown. Dirty yellowish brown. Orange yellow. Yellow, with both the protoxide and peroxide salts. White. Orange Yellow. Yellowish brown. No precip. Blue. No precip. The ferric-oyanide of potassium has been introduced into dyeing and calico-printin- In e,ise an excess of chlorine has been used in preparing the above salt Poiett recommends to add to its solution, when near the ery^lline point a ?ew dropsof po nsh lye, in order to decompose a green substance thit is present ihich takes place with the precipitation of a little peroxide of iron. ^ FERROCYANATE or, more correctly, FERROCYANIDE. (Ferrocyanure Fr • Etsencyanid Germ.) Several compounds of cyanogen and metals possess Ihe prineri; of uni mg together into double cyanides ; of which there are none so remark ableTnthS respec,as the protocyanide of^ iron. This appears to be capable of combtn L with several simple cyanides, such as that of potassium, sodium, barium, s.^ntium" cflcUim and ammonium. The only one of these double cyanides of any importance in man' ufacfires is the first, which is described under its commercial name, Prussiatk «; FERROPRUSSIATES; another name for Ferrocyanides FIBRE, VEGETABLE, called also Lignine (Ligneux Fr • P/fan^^ r / /r Germ.) is the most abundant and general ingredient^oTpS, fxiVtingt a^tfef ^ o'qt'^ 'q^ ^''''!' ^\V.'^"^^/'?" ^^.^^••«> «"^ '^' ^'••"'^ ; amounting in^Le compact w^ W ll hV"'?"^ /' '' obtamedm a pure state by treating sawfdust successively whh hot alcohol, water, dilute muriatic acid, and weak potash l?y, which dissofve first the inirr' «^/°"^;/he extractive and saline matters ; third, the carbonatran^^^^^^^ of hme ; and, astly, any residuary substances. Ligneous fibres, such as saw-dus° Cw- dered barks, s raw hemp, flax, linen, and cotton cloth, are convertible by the aciorrf Slnrthato're 7^,^'' ' '"""' ^"'^^^"^^ ^'^'^^^^^^^ '^ ^'--' ^^^ sugaT re'^m- an5^nrinkll'n!^.^•f'qT ""T"/^ ?T'-^^ ^"'^'^^' «^ ^^y ^^ cordage, chopped smaU, and sprmkle over it 34 parts of sulphuric acid, by degrees, so as to avoid heating the mixture, while we constantly stir it; and if, in a quarter of an hour we trifulte the ti^fur ""^^ ^^^ r'^ ^^ produced, almost entirely soluble in waier. The |um being thus formed, may be separated from the acid by dilution with water, and additi^ of the requisite quantity of chalk; then straining the saturated liquid through lineS cloth, concentrating it by evaporaUon, throwing down any remaining hme b^r oxaUt 708 FIBRINE. FILE. 709 \¥l^ mcid, filtering anew, and mixing the mucilage wiih alcohol in great excess, which will take up the free acid, and throw down the gum. From 24 parts of hemp fibres thiis treated, fully 24 parts of a gummy mass may be obtained, containing, however, probabiy When instead of saturating the diluted acid paste with chalk, we boil it for 10 hour*, the gummy matter disappears, and is replaced by sugar, which may be purified without any difficulty, by saluraiion with chalk, filtration, and evaporation to the consistence of sirup In 24 hours crystallization begins, and, in 2 or 3 days, a concrete mass of grape sugar is formed; which needs merely to be pressed strongly between old linen cloths doubled, and then crystallized a second time. If this sirup be treated with bone black, a brilliant white sugar will be procured. 20 parts of linen rags yield 23 of good sugar. Braconnot. Guerin got 87| of dry sugar from 100 parts of rags, treated with 250 of sul- phuric acid. See Wood. . .. • • i , FIBRINE (Eng. and Fr. ; Thierischer Fasersioff, Germ.) constitutes the principal pari of animal muscle ; it exists in the chyle, the blood, and may be regarded as the most abundant constituent of animal bodies. It may be obtained in a pure state by agjtaling or beating new drawn blood with a bundle of twigs, when it will attach itself to them in lon«' reddish filaments, which may be deprived of color by working them with the hands und'er a streamlet of cold water, and afterwards freed from any adhering grease by diges- tion in alcohol or ether. ,.,,,.••,• j a „«,«, Fibrine, thus obtained, is solid, white, flexible, slightly elastic, insipid, inodorous, denser than water, but containing four fifths of its weight of it, and without action on litmus. When dried, it becomes semi-transparent, yellowish, stiff, and brittle : water restores its softness and flexibility. 100 parts of fibrine consist of 53-36 carbon, 19-68 oxygen, 7-02 hydrogen, and 19-31 azote. As the basis of flesh, it is a very nutritious substance, and is essential to the sustenance of carnivorous animals. , . * *i. FILE {Lime, Fr. ; Feile. Germ.) is a well known steel instrument, having teeth upom the surface for cutting and abrading metal, ivory, wood, &c. , j , • i , a When the teeth of these instruments are formed by a straight sharp-edged chisel, extend- ing across the surface, they are properly called files ; but when by a sharp-pmnled tool, in the form of a triangular pyramid, they are termed rasps. The former are used for all the metals, as well as ivory, bone, horn, and wood ; the latter for wood and horn. Files are divided into two varieties, from the form of their teeth. When the teeth are a series of sharp edges, raised by the flat chisel, appearing like parallel furrows, either at right angles to the length of the file, or in an oblique direction, they are termed single cut But when these teeth are crossed by a second series of similar teeth, they are said to be double cut. The first are fitted for brass and cop|)er, and are found to answer bet- ter when the teeth run in an oblique direction. The latter are suited for the harder met- als such as cast and wrouslit iron and steel. Such teeth present sharp angles to the sub- stance, which penetrate it, while single cut files would slip over the surface of these met- als. The double cut file is less fit for filing brass and copper, because its teeth would be very liable to become clogged with the filings. Files are also called by different names according to their various degrees of fineness. Those of extreme roughness are called rough ; the next to this is the bastard cut; the third is the second cut ; the fourth, the smooth ; and the finest of all, the dead smooth. The very heavy square files used for heavy smith-work, are sometimes a little coarser than the rough ; they are known by the name of rubbers. „ , ,^ . ^^ > FiWare also distinguished from their shape, as flat, half-round three-square, four- square, and round. The first are sometimes of uniform breadth and thickness throughout, and sometimes tapering. The cross section is a parallelogram. The half-round is gen- erally tapering, one side being flat, and the other rounded. The cross section is a seg- ment of a circle, varying a little for different purposes, but seldom equal to a semi-circ e. The three-square generally consists of three equal sides, being equUateral prisms, mostly tapering; those which are not tapering are used for sharpening the teeth ol saws. Ihc four-square has four equal sides, the section being a square. These files are generaUy thickest in the middle, as is the case with the smith's rubber. In the round file, the sec- tion is a circle, and the file generally conical. , r vv ♦ -^ The heavier and coarser kinds of files are made from the inferior marks of blistered steel Those made from the Russian iron, known by the name of old sable, called from its m'ark CCND, are excellent. The steel made from the best Swedish iron, called hoop L or Dannemora, makes the finest Lancashire files, for watch and clock makers ; a man- ufacture for which the house of Stubbs in Warrington is celebrated. The steel intended for files is more highly converted than for other purposes, to give them proper hardness. It should however be recollected, that if the l^^rdness be no» accompanied with a certain degree of tenacity, the teeth of the file break, and do but litdc ** faSi files are mostly made of cast steel, which would be the best for all others, if ft were not for its higher price. It is much harder than the blistered steel, and fiom having been in the fluid state, is entirely free from those seams and loose parts so common to blistered steel, which is no sounder than as it comes from the iron forge before con- version. The smith's rubbers are generally forged in the common smith's forge, from the con- verted bars, which are, for convenience, made square in the iron before they come into this country. The files of lesser size are made from bars or rods, drawn down from the Mistered bars, and the cast ingots, and known by the name of tilted steel. The file-maker's forge consists of large bellows, with coke as fuel. The anvil-block, particularly at Sheffield, is one large mass of mill stone girt. The anvil is of consider- able size, set into and wedged fast into the stone; and has a projection at one end, with a hole to contain a sharp-edged tool for cutting the files from the rods. It alsc contains a deep groove for containing dies or bosses, for giving particular forms to the files. The flat and square files are formed entirely by the hammer. One man holds the hot bar, and strikes with a small hammer. Another stands before the anvil with a two-hand- ed hammer. The latter is generally very heavy, with a broad face for the large files. They both strike with such truth as to make the surface smooth and flat, without what is called hand-hammering. This arises from their great experience in the same kind of work. The expedition arising from the same cause is not less remarkable. The half-round files are made in a boss fastened into the groove above mentioned. The steel being drawn out, is laid upon the rounded recess, and hammered till it fills the die. The three-sided files are formed similarly in a boss, the recess of which consists of two sides, with the angle downwards. The steel is first drawn out square, and then placed in a boss with an angle downwards, so that the hammer forms one side, and the boss two. The round files are formed by a swage similar to those used by common smiths, but a little conical. The file-cutter requires an anvil of a size greater or less, proportioned to the size of his files, with a face as even and flat as possible. The hammers weigh from one to five or six pounds. The chisels are a little broader than the file, sharpened to an angle of about 20 degrees. The length is just sufficient for them to be held fast between the finger and thumb, and so strong as not to bend with the strokes of the hammer, the intensity of which may be best conceived by the depth of the impression. The anvil is placed in the face of a strong wooden post, to which a wooden seat is attached, at a small distance be- low the level of the anvil's face. The file is first laid upon the bare anvil, one end pro- jecting over the front, and the other over the back edge of the same. A leather strap now goes over each end of the file, and passes down upon each side of the block to the workman's feet, which, being put into the strap on each side, like a stirrup, holds the file firmly upon the anvil as it is cut. WhUe the point of the file is cutting, the strap passes over one part of the file only, the point resting upon the anvil, and the tang upon a prop on the other side of the strap. When one side of the file is single cut, a fine file is run slightly over the teeth, to take away the roughness ; when they are to be double cut, another set of teeth is cut, crossing the former nearly at right angles. The file is now finished upon one side, and it is evident that the cut side cannot be laid upon the bare anvil to cut the other. A flat piece of an alloy of lead and tin is interposed between the toothed surface and the acvil, while the other side is cut, which completely preserves the side already formed. Similar pieces of lead and tin, with angular and rounded grooves are used for cutting triangular and half-round files. ' Rasps are cut precisely in the same way, by using a triangular punch instead of a flat chisel. The great art in cutting a rasp is to place every new tooth as much as possible opposite to a vacancy. IVfany abortive attempts have been made to cut the teeth of files by machinery. Th* following plan, for which a patent was obtained by Mr. William Shilton, of Birming- ham, in April, 1833, is replete with ingenious mechanical resources, and deserves to succeed. The blanks of steel for making the files and rasps, are held in a pair of clamps in connexion with a slide, and are moved forward at intervals under the head of the tilt hammer which carries the tool ; the distance which the blank is to be advanced at every movement being dependant upon the required fineness or coarseness of the cut of the file, TThich movement is effected and regulated by a rack and pinion, actuated by a pall and ratchet wheel, or the movement may be produced by any other convenient means. When the machine is employed for cutting or indenting the teeth of rasps, the cutting tool being pointed and only producing one tooth at a blow, the tilt hammer carrying th« tool mast be made to traverse at intervals across the width of the blank piece of steel 710 FILE. FILE- 711 from one edge to the other and back again ; the blank being advanced m jength only when the hammer has produced the last cut or tooth toward either edge of the rasp. In order to render this invention better understood, two views of the apparatus for pro- ducing the cross-cut or teeth of the files are given. Fig, 527 is an elevation of the upper part of the file-cutting machine, as seen on one side ; fig, 528 is • plan or horizontal view, as the ma- chine appears on the top. a, is the head of the lilt hammec placed in the end of the lever In, which is mounted on an axle c, turning in proper bearings in the framework of the machine ; d, is the tilt wheel mounted on another axle s, also turning in bearings on the frame work of the machine, and having any required number of projections or tappets npon it for depressing the tail or shorter end of the hammer or tilt lever 6. The tilt wheel d, receives its rota- tory motion from the toothed wheel /, mounted upon the same axle, and it takes into gear with a pinion g, upon the main shaft A, which is ac- tuated by a band passed from any first mover to the rigger on its end, or in any other convenient manner. The bed upon which the blank piece of steel bears is marked i. This bed is firmly supported upon masonry placed upon proper sleepers ; _;', is one of the blank pieces of steel under operation, and is shown secured in the pair of jaws or holding clamps fc, mounted on centre pins in the slide /, fig. 528 ; which slide is held down by a spring and slide beneath, and is moved backwards and forwards in the machine upon the (v) edges m, tw, of the frame, by means of the rack n, and its pinion ; the latter being mounted upon the axle of the ratchet wheel |J, and which ratchet wheel is made to turn at intervals by means of the pall g, upon the end of the lever r, fig. 528. This lever is depressed, after every cut has been efi'ected upon the blank by means of the teeth or tappets of the wheel «, coming in contact with the inclined plane t, upon the lever r. The tappet wheel *, is mounted upon the end of the axle e, of the tilt wheel, and consequently revolves with it, and by depressing the lever r, every time that a tooth passes the inclined plane /, the click g, is made to drive the ratchet wheel p, and thereby the advancing movement of the blank is effected after each blow of the tilt hammer. There is a strong spring «, attached to the upper side of the tilt hammer, its end being confined under an adjustable inclined plane r, mounted in the frame U', which inclined plane can be raised or lowered by its adjusting screws as required, to produce more or less tension of the spring. A similar spring is placed on the under side of the tilt hammer, to raise and sustain the cutter or tool clear of the bed after every blow, and in conjunction with safety hold- ers or catchers, to counteract any vibration or tendency the spring u may have to cause the hammer to reiterate the blow. The end of the lower spring acts on an inclined plane, mounted in the frame w, which has an adjusting screw similar to r, to regulate the tension of the spring. In case the under spring should raise, that is, return the hammer, with sufficient force or velocity to cause the top spring t*, to reiterate the blow, the ends of the safety holders or catchers are made to move under and catch the tail of the lever 6, immediately on its being raised by the under springs, whidi is effected by the following means : — The hold- ers are mounted upon a plate or carriage 1, fig. 527, which turns upon a small pin or axle mounted in the cars of a cross bar ; the upper ends of the holders are kept inclined towards the tail of the tilt hammer by means of^a spring fixed to the cress bar, and which aeu upon one end of the plate or carriage 1. r In order that the holders may be removed out of the way of the tail of the hammer h, when the tilt wheel is about to effect a blow, the tooth of the tilt wheel which last acted upon the hammer comes in contact with an inclined plane fixed on the plate or carnage 1 and by depressing that end of the plate, causes the upper ends of the holders to be withdrawn from under the tail of the hammer b. The tilt wheel continuing to revolve, the next tooth advances, and depresses the tail of the hammer, but before it leaves the tail of the hammer, the tooth last in operation will have quitted the inclined plane and allowed the spring to return the holders into their former position. After the tooth has escaped from the tail of 6, the hammer will immediately descend and effect the blow or cut on the blank, and as the tail of the hammer rises, it will come in contact with the inclined planes at the upper ends of the holders, and force them backwards ; and as soon as the tail of the hammer has passed the top of the holders, the spring will immediately force the holders forward under the tail of the hammer, and prevent the hammer rising again until the next tooth of the tilt wheel is about to depress the end of the hammer, when the same movements of the parts will be repeated, and the machine will continue in operation until a sufficient length of the blank of steel (progressively advanced under the hammer) has been operated upon, when it will be thrown out of gear by the following means : — .,.,!./•• Upon the sliding bar 6 there is placed an adjustable stop, against which the foremost end of the slide 1 1, fig. 528, comes in contact as it is moved forward by the rack n, and its pinion. The sliding bar 6 is connected at its left end to the bent lever 8, the other end of this lever being formed into a forked arm, which embraces a clutch upon the main shaft, and as the slide I continues to advance, it will come in contact with a slop ; and when it has brought a sufficient length of the blank pieces of steel under the operation of the cutting tool, the slide /, in its progress, will have moved that stop and the bar 6 forward, and that bar, by means of the bent lever 8, will withdraw the clutch on the main shaft, from locking into the boss of the fly-wheel, and consequently stop the further progress of the machine ; the rigger and fly-wheel turning loosely upon the main shaft. The cut file can now be removed from out of the clamps, and reversed to cut the other side, or another blank piece put in its place ; and after throwing back the pall q of the ratchet wheel p, the slide Z, and with it the fresh blank may be moved back into the machine by turning the winch handle, on the axle of the ratchet wheel p, the reverse way, which will turn the pinion backwards, and draw back the rack n, without affecting any other parts of the machine ; and on moving back the bar 6, by the handle 11, placed on the stop, the clutches will be thrown into gear again, and the machine proceed to cut the next blank. When the blanks have been thus cut on one side, and are reversed in the machine to form the teeth upon the other side, there should be a piece of lead placed between the blank and the bed to protect the fresh cut teeth. It will be seen that the position of the stop upon the bar 6 will determine the length or extent of the blank piece of steel which shall be cut or operated upon ; and in order that the progressive movement of the blanks under the cutting tool may be made to suit different degrees of fineness or coarseness of the teeth (that is, the distance between the cuts), there'is an adjusting screw upon the lever r, the head of which screw stops against the under side of an ear projecting from the frame-work, and thereby determines the extent of the motion of the lever r, when depressed by the tappets of the wheel », acting upon the inclined plane /, consequently determining the number of teeth the ratchet wheel p shall be moved round by the pall q ; and hence the extent of motion communi- cated by the rack and pinion to the slide i, and the blank j, which regulates the distance that the teeth of the file are apart, and the lever r is forced upwards by a spring pressing against its under side. Ii will be perceived that the velocity of the descent of the hammer, and consequently the force of the blow, may be regulated by raising or lowering the inclined plane v of the spring tt ; and in order to accommodate the bed upon which the blanks rest to the differ- ent inclinations they may be placed at, that part of the bed is formed of a serai-globular piece of hardened steel, which fits loosely into a similar concavity in the bed r, and u therefore capable of adjusting itself so that the blanks shall be property presented to the cutting tool, and receive the blow or cut in an equal and even manner ; or the piece of steel may be of a conical shape, and fit loosely in a similar shaped concavity. There are guides, 16, placed on thr top of the bed i, for the purpose of keeping the blanks in their proper position towards the cutting tool, and these can be regulated to suit blanks of any width, by turning the right and left handed screw 17. There is also another adjustable stop on the jaws or clamps fe, which serves as a guide when placing the blanks within the jaws; and 19 is a handle or lever for raising the clamps when required, which has a weight suspended from it for the purpose of keeping down the blanks with sufficient pressure upon the bed. . , , The cutting tool in the face of the hammer, can be placed at any required angle or 712 FILE. FILTRATION. 713 i \Vi i ■ inclination with the blank, it being secured in the head of the hammer by clamps and screws. In cutting fine files a screw is employed in preference to the rack and pinion, for advancing the slide /, and the blank piece of steel in the machine. Hardening of files. — This is the last and most important part of file making. What- ever may be the quality of the steel, or however excellent the workmanship, if it is not well hardened all the labor is lost. Three things are strictly to be observed in hardening ; first, to prepare the file on the surface, so as to prevent it from being oxydated by the atmosphere when the file is red hot, which effect would not only take off the sharpness of the tooth, but render the whole surface so rough that the file would, in a little time, become clogged with the substance it had to work. Secondly, the heat ought to be very uniformly red throughout, and the water in which it is quenched, fresh and cold, for the purpose of giving it the proper degree of hardness. Lastly, the manner of immersion is of great importance, to prevent the files from warping, which in long thin files is very difficult. The first object is accomplished by laying a substance upon the file, which, when it fuses, forms, as it were, a varnish upon the surface, defending the metal from the action of the oxygen of the air. Formerly the process consisted in first coaling the surface of the file with ale grounds, and then covering it over with pulverized common salt (muri- ate of soda). After this coating became dry, the files were heated red hot, and hardened; after this, the surface was lightly brushed over with the dust of cokes, when it appeared white and metallic, as if it had not been heated. This process has lately been improved, at least so far as relates to the economy of the salt, which, from the quantity used, and the increased thickness, had become a serious object. Those who use the improved method are now consuming about one fourth the quantity of salt used in the old method. The process consists in dissolving the salt in water to saturation, which is about three pounds to the gallon, and stiffening it with ale grounds, or with the cheapest kind of flour, such as that of beans, to about the consistence of thick cream. The files require to be dipped only into this substance, and immediately heated and hardened. The grounds or the flour are of no other use than to give the mass consistence, and by that means to allow a larger quantity of salt to be laid upon the surface. In this method the salt, forms immediately a firm coating. As soon as the water is evaporated, the whole of it becomes fused upon the file. In the old method the dry salt was so loosely attached to the file, that the greatest part of it was rubbed off into the fire, and was sublimed up the chimney, without producing any effect. The carbonaceous matter of the ale grounds is supposed to have some effect in giving hardness to the file, by combining with the steel, and rendering it more highly carbon- ated. It will be found, however, upon experiment, that vegetable carbon does not com- bine with iron, with sufficient facility to produce any effect, in the short space of time a file is heating for the purpose of hardeninff. Some file makers are in the habit of using the coal of burnt leather, which doubtless produces some effect ; but the carbon is generally so ill prepared for the purpose, and the time of its operation so short, as to render the result inconsiderable. Animal carbon, when properly prepared and mixed with the above hardening composition, is capable of giving hardness to the surface even qS an iron file. This carbonaceous matter may be readily obtained from any of the soft parts of ani- mals, or from blood. For this purpose, however, the refuse of shoemakers and curriers is the most convenient. After the volatile parts have been distilled over, from an iron still, a bright shining coal is left behind, which, when reduced to powder, is fit to mix with the salt. Let about equal parts, by bulk, of this powder, and muriate of soda be ^ound together, and brought to the consistence of cream, by the addition of water. Or mix the powdered carbon with a saturated solution of the salt, till it become of the above consistence. Files which are intended to be very hard should be covered with this composition previous to hardening. All files intended to file iron or steel, particularly saw files, should be hardened with the aid of this mixture, in preference to that with the flour or grounds. Indeed, it is probable that the carbonaceous powder might be used by itself, in point of economy, since the ammonia or hartshorn, obtained by distillation, would be of such value as to render the coal of no expense. By means of this method the files made of iron, which, in itself, is unsusceptible of hardening, acquire a superficial hardness sufficient for any file whatever. Such files may, at the same lime, be bent into any form ; and, in consequence, are particularly useful for scnlp- tors and die-sinkers. The next point to be considered is the best method of heating the file for hardening. For this purpose a fire, similar to the common smith's fire, is generally employed. The file is held in a pair of tongs by the tang, and introduced into the fire, consisting of very small cokes, pushing it more or less into the fire for the purpose of heating it regularly. It must frequently be withdrawn with the view of observing that it is not too hot in any part. When it is uniformly heated, from the tang to tie point, of a eherry red color, it is fit to quench in the water. At present an oven formed of fire- bricks is used for the larger files, into which the blast of the bellows is directed, bemg open at one end, for the purpose of introducing the files and the fuel. Near to the top of the oven are placed two cross bars, on which a few tiles are placed, to be partially heating. In the hardening of heavy files this contrivance affords a considerable sav- ing, in point of time, while it permits them also to be more uniformly and thoroughly heated. . ^ j .u After the file is properly heated for the purpose of hardening, in order to produce the greatest possible hardness, it shoiild be cooled as soon as possible. The most common method of effecting this is by quenching it in the coldest water. Some file-makers have been in the habit of putting different substances in their water, with a view to increase its hardening property. The addition of sulphuric acid to the water was long held a great secret in the hardening of saw files. After all, however, it will be-found that clear spring water, free from animal and vegetable matter, and as cold as possible, is the best calculated for hardening files of every description. In quenching the files in water, some caution must be observed. All files, except the half-round, should be immersed perpendicularly, as quickly as possible, so that the upper part shall not cool. This management prevents the file from warping. The half-round file must be quenched in the same steady manner ; but, at the same time that it is kept perpendicular to the surface of the water, it must be moved a little horizontally, in the direction of the round side, otherwise it will become crooked backwards. After the files are hardened, they are brushed over with water and powdered cokes, when the surface becomes perfectly clean and metallic. They ought also to be washed well in two or three clean waters, for the purpose of carrying off all the salt, which, if allowed to remain, will be liable to rust the file. They should moreover be dipped into lime-water, and fapidly dried before the fire, after being oiled with olive oil, containing a little oil of turpentine, while still warm. They are then finished. FILLIGREE (Filigrane, Fr. ; FUigran, or Peine Drahtgeflecht, Germ.) is, as the last term justly expresses it, intertwisted fine wire, used for ornamenting gold and silver trinkets. The wire is seldom drawn round, but generally flat or angular, and soldered by gold or silver solder with borax and the blowpipe. The Italian word, fiiligranay is compounded of filum and granum, or granular net- work ; because the Italians, who first introduced this style of work, placed small beads upon it. FILTRATION (Eng. and Fr. ; Filtriren, Germ.) is a process, purely mechanical, for separating a liquid from the undissolved particles floating in it, which liquid may be either the useful part, as in vegetable infusions, or of no use, as the washings of mineral pre- cipitates. The filtering substance may consist of any porous matter in a solid, folia- ted, or pulverulent form ; as porous earthenware, unsized paper, cloth of many kinds, or sand. The white blotting paper sold by the stationers, answers extremely well for filters in chemical experiments, provided it be previously washed with dilute muriatic acid, to remove some lime and iron that are generally present in it. Filter papers are first cut square, and then folded twice diagonally into the shape of a cornet, having the angular parts rounded off. Or the piece of paper being cut into a circle, may be folded fan-like from the centre, with the folds placed exteriorly, and turned out sharp by the pressure of the finger and thumb, to keep intervals between the paper and the funnel into which it IS fitted, to favor the percolation. The diameter of the funnel should be about three fourths of its height, measured from the neck to the edge. If it be more divergent, the slope will be too small for the ready efflux of the fluid. A filter covered with the sedi- ment is most conveniently washed by spouting water upon it with a little syringe. A small camel's-hair paint brush is much employed for collecting and turning over the con- tents in their soft state. Agitation or vibration is of singular efficacy in quickening per- colation, as it displaces the particles of the moistened powders, and opens up the pores which had become closed. Instead of a funnel, a cylindrical vessel may be employed, having its perforated bottom covered with a disc of filtering powder folded up at the edges, and made light there by a wire ring. Linen or calico is used for weak alkaline liquors ; and flannels, twilled woollen cloth, or felt-stuff, for weak acid ones. These filter bags are often made conical like a fool's cap, and have their mouths supported bf a wooden or metallic hoop. Cotton wool put loose into the neck of a funnel answers well for filtering oils upon the small scale. In the large way, oil is filtered in conical woollen bags, or in a cask with many conical tubes in its bottom, filled with tow or cotton wool. Stronger acid and alkaline liquors must be filtered through a layer of pounded glass, quartz, clean sand, or bruised charcoal. The alcarrhazas are a porous biscuit of stone ware made in Spain, which are convenient f r filtering water, as also the porous filtering stone of Teneriffe, largely imported into England at one time, but now siiperseded ma great measur eby the artificial filters patented under many forms, consisting essentially of siraia of e:ravel, sand, and charcoal powder. r t -j It is convenient to render the filter self-acting, by accommodating the supply of liqu«| 1 714 FILTRATION. FILTRATION. 715 to the rate of percolation, so that the pressure upon the porous surface may be always equally great. Upon the small scale, the lamp-fountain or birdVglass form, so generally used for lamps, will be found to answer. Fig. 529 represents a class bottle, a, partly filled with the fluid to be filtered, supported in the ring of a chemical stand, and having its mouth inverted into the same liquor in the filter funnel. It is obvious that whenever this liquor by filtration falls below the lip of the boille, air will enter into it. let down a fresh supply to feed the filter, and keep the funnel regularly charged. If larger quantities are to be operated upon, the following apparatus may be employed. Fig. 530, A B, is a metallic vessel which may be made air- tight ; c is the under pipe, provided with a stopcock, R, for letting down the liquor into the filter a 6. The upper pipe /, through which the fluid is poured by means of the funnel e, has also a stopcock which opens or shuts, at the same time, the small side tube u tf through which, during the entrance of the fluid, the air is let off from the receiver. A glass tube, g, shows the level of the liquor in the body of the apparatus. In using it, the cock r must be first closed, and the cock s must be opened to fill the receiver. Then the filter is set a going, by re-open- ing the cock R, so as to keep the fluid in the filter upon a level with the opening of the tube c. Both these pieces of apparatus are essentially the same. In many manufactures, self-acting filters are fed by the plumber's common con- 533 531 I ! triytnce of a ball-cock, in which the sinking and rising of the ball, within certain limits, serves to open or 532 _ n i l ' I I shut off the supply o| liquor, as it may be re- quired or not. Dumont has adopted this expedient for his system of filtering sirup through a stratum of granularly ground animal charcoal or bone-black. Fig. 531 is a front view of this apparatus with 4 filters, c ; and^^. 532 is a cross section. The frame- work B supports the cis- tern a, in which the sirup is contained. From it the liquor flows through the stopcoek 6, and the connexion-tube a, into the common pipe c, which communicates, by the short branch tubes «, with each of the four filters. The end of the branch tube, which is inside of the filler tub, is provided with a stop-cock d /, whose opening, and thereby the efflux of tne liquor from the cistern through the tube a, is regulated by means of the float-ball g. Upon the brickwork d the filter tub stands, furnished at h. with a false bottom of zinc or copper pierced with fine holes ; besides which, higher up at t there is another such plate of metal furnished with a strong handle fc, by which it may be removed, when the bone black needs to be changed. In the intervening space /, the granular coal is placed, o is the cover of the filter tub, with a handle also for lifting it. One portion of it may be rais- ed by a hinge, when it is desired to inspect the progress of the filtration within, m m is a slender vertical tube, forming a communication between the bottom part A, and the upper portion of the filter, to admit of the easy escape of the air from that space, and from among the bone black as the sirup descends ; otherwise the filtration could not go on. p is the stopcock through which the fluid collected in the space under h, is let off from time to time into the common pipe g,^g. 531. r is a trickling channel or groove lying parallel to the tube 9, and in which, by means of a tube «, inserted at pleasure, the sirup is drawn off in case of its flowing in a turbid state, when it must be returned over the surface of the charcoal. The celerity with which any fluid passes through the filter depends, 1. upon the porosi- ty o{ the filtering substance ; 2. upon the pressure exercised upon it ; and 3. upon the ex- tent of the filtering surface. Fine powders in a liquor somewhat glutinous, or closely compacted, admit of much slower filtration than those which are coarse and free ; and the former ought, therefore, to be spread in a thinner stratum and over a more extensive sur- face than the latter, for equal effect ; a principle well exemplified in the working of Da- monl's apparatus, just described. In many cases filtration may be accelerated by the increase of hydrostatic or pneu- matic pressure. This happens when we close the top of a filtering cylinder, and con- nect it by a pipe with a cistern of fluid placed upon a higher level. The pressure of the air may be rendered operative also either by withdrawing it partially from a close vessel, into which the bottom of the filter enters, or by increasing its density over the top of the liquor to be filtered. Either the air pump or steam may be employed to create a partial void in the receiver beneath the filter. In like manner, a forcing pump or steam may be employed to exert pressure upon the surface of the filtering liquor. A common syphon may, on the same principle, be made a good pressure filter, by making its upper leg trumpet-shaped, covering the orifice with filter paper or cloth, and filling the whole with liquor, the lower leg being of such length so as to create considerable pressure by the difference of hydrostatic level. This apparatus is very convenient either on the small or great scale, for filtering off a clear fluid from a light muddy sediment. The pressure of the atmosphere may be elegantly applied to common filters, by the appa- ratus represented in^g. 533, which is merely a funnel enclosed within a gasometer. The case A B bears an annular hollow vessel o 6, filled with water, in which receiver the cyl- indrical gasometer (i, e, /, t, is immersed. The filter funnel is secured at its upper edge to the inner surface of the annular vessel a h. In consequence of the pressure of the gasometer regulated by the weight g, upon the air enclosed within it, the liquid is equally pressed, and the water in the annular space rises to a corresponding height on the outer surfcij? of the gasometer, as shown in the figure. Were the apparatus made of wheet iron, the annular space might be charged with mercury. In general, relatively to the application of pressure to filters, it may be remarked, that it cannot be pushed very far, without the chance of deranging the apparatus, or rendering the filtered liquor muddy. The enlargement of the surface is, generally speaking, the safest and most eflicacious plan of increasing the rapidity of filtration, especially for liquids of a glutinous nature. This expedient is well illustrated in the creased bag filter now in use in most of the sugar refineries of London. See Sugar. In many cases it is convenient so to construct the filtering apparatus, as that the liquid shall not descend, but mount by hydrostatic pressure. This method has two advantages : 1. that without much expensive apparatus, any desired degree of hydro- static pressure may be given, as also that the liquid may be forced up through several fil- tering surfaces placed alongside of each other ; 2. that the object of filtering, which is to separate the particles floating in the fluid without disturbing the sediment, may be per- fectly attained, and thus very foul liquids be cleared without greatly soiling the filtering surface. Such a construction is peculiarly applicable to the purification of water, either alone, or combined with the downwards plan of filtration. Of the former variety an example is shown in fig, 534. The wooden or zinc conical vessel is provided with two per- forated bottoms or sieves e e, betwixt which the filtering substance is packed. Over this, for the formation of the space h A, there is a third shelf, with a hole in its diddle, through which the lube d 6 is passed, so as to be water tight. This places the upper 716 FILTRATION. FIRE ARMS. 717 I I open part of the apparatus in communicaiion with the lowest space a. From the com* partment h h & small air tube / runs upwards. The filtering substance consists at bottom of pebbles, in the middle of gravel, and at the top of fine sand, which may be mixed with coarsely ground bone black, or covered with a layer of the same. The water to be filter- ed being poured into the cistern at top, fills through the tube 6 d the inferior compartment a, from which the hydrostatic pressure forces the water upward through the perforated shelf, and the filtering materials. The pure water collects in the space h A, while the air escapes by the small tube /, as the liquid enters. The stopcock t serves to draw off the filtered water. As the motion of the fluid in the filter is slow, the particles suspended in it have time to subside by their own gravity ; hence there collects over the upper shelf at d, as well as over the under one at a, a precipitate or deposite which may be washed out of the latter cavity by means of the stopcock m. As an example of an upwards and downwards filter, ^g. 535 may be exhibited, a b cd 535 JP 'm ■■■■■■HKji^amaMn a I E vf a n \% '•»}i)iHI»)W)}))»}>}>l}>ll}rTTT7Tt 534 I is a wooden or metallic cistern fur- nished with the perforated shelf c d near its under part, upon which a vertical partition is fixed through the axis of the vessel. A semi- circular perforated shelf is placec at a, and a second similar one at 6. These horizontal shelves rest upon brackets in the sides of the cisterns, so that they may be read- ily lifted out. The space g is filled with coarse sand, J with mod- erately fine, and h with very fine. The foul water is poured into the chamber £, and presses through G J H and into the space f ; whence it may be drawn by the stop- cock/. JFig. 536 represents in section a filtering apparatus consisting of two concentric chambers; the interior being destined for downwards filtration, and the exterior for Within the larger cistern a, a smaller one b is placed concentrically, with its under part, and is left open from H distance to distance, to make a communication between the in- terior cavity and the exterior annular space. These cavities Jc upwards 536 to the marked height sand and gravel. The cylindrical space has fine below, then sharper sand granular charcoal, next sand, and lastly gravel. are filled with inner sand with coarse The annular space has in like manner fine sand below. The foul water is introduced by the pipe £, the orifice at whose end is acted upon by a ball-cock with its lever a ; whereby the water is kept always at the same level in the inner vessel. The water sinks through the sand strata of the middle vessel, passes outwards at its bottom into the annular space, thence up through the sand in it, and collecting above it, is let off by the stopcock on the pipe h. When a muddy deposite forms after some time, it may be easily cleared out. The cord «, running over the pulleys //, being drawn tight, the ball lever will shut up the valve. The stopcock d made fast to the conducting tube e must then be opened, so that the water now overflows into the annular space at a ; the tube c, in communication with the inner space b, being opened by taking out the stopper h. The water thereby percolates through the sand strata in the reverse direction of irj usual course, so as to clear away the impurities in the space b, and to discharge them by the pipe c h. An apparatus of this kind of moderate size is capable of filtering a great body of water. It should be constructed for that purpose of masonry ; but upon a small scale it may be made of stone- ware. A convenient apparatus for filtering oil upwards is represented in^g. 537. g is an oil eosk, in which the impure parts of the oil have accumulated over the bottom. Imme- diately above this, a pipe a is let in, which communicates with an elevated water cistern • f is the filter (placed on the lid of the cask), furnished with two perforated shelves, oie at t and another at d; which divide the interior of the filter into t»ree <5o»n. partments. Into the lower space immedmtely over the shelf «, the tube 6, furnished with a stopcok, enters, to establish a communicaiion with the cask ; the middle cavity t is filled with . coarsely ground charcoal or other filtering materials ; and the "11 ^iMrfK upper one has an eduction pipe, /. When the stopcocks of the ^^"7t'l°'r"P'«"'/I v« leys. In proportion as these flow down, they will displace their bulk of air, and drive it into the top of the upper vessel above the foul leys. , • »u- ««„«t«r. Many modifications of the above described apparatus are now on sale in this countiy, but certainly the neatest, most economical, and effective means of transforming the water of a stagnant muddy pool into that of a crystalline fountam, is afforded by the Royal Patent Filters of George Robins. .,..,,... v u ♦i, ♦ ^r «».- FIRE ARMS, Manufacture of. This art is divided into two branches that of the metallic and of the wooden work. The first includes the barrel, the lock, and the mount- ing, as also the bayonet and ramrod, with military arms. The second comprises the stock, and in fowling pieces, likewise the ramrod. 1. The, Barrel. Its interior is called the bore; Us diameter, the calibre ; the back end, the breech ; the front end, the muzzle ; and the closing of the back end, the breech Din or pluc. The barrel is generally made of iron. Most military muskets and low- priced guns are fashioned out of a long slip of sheet-iron, folded together edgewise round a skewer into a cylinder, are then lapped over at the seam, and welded at a while heat. The most ductile and tenacious soft iron, free from aU blemishes, must be selected for this slip. It is frequently welded at the common forge, but a proper atr- furnace answers better, not being so apt to burn it. It should be covered with ashes or cinders. The shape of the bore is given by hammering the cylinder upon a sted mandril, in a groove of the anvil. SLv inches of the barrel at either end are left open for formin" the breeck ind the muzzle by a subsequent welding operation ; the extrem- ity put into the fire be:ng stopped with clay, to prevent the introduction of cinders. For every leneth of two inches there are from two to three welding operations, divided into alternating high and low heats ; the latter being intended to correct the defects of the former. The breech and muzzle are not welded upon the mandril, but upon the horn of the anvil ; the breech being thicker in the metal, is more highly heated, and is made somewhat wider to save labor to the borer. The barrel is finally hammered m the groove of the anvil without the mandril, during which process it receives a heat eveiT two minutes. In welding, the barrel extends about one third in length ; and for muskets, is eventually left from 3 to 3^ feet long ; but for cavalry pistols, only 9 The best iron plates for gun-barrels are those made of stub iron, that is, of old horse-shoe nails welded together, and forged into thin bars, or rather narrow ribands. At one time datnascus barrels were much in vogue ; they were fashioned either as aoove described, from plates made of bars of iron and steel laid parallel, and welded together, or from ribands of the sauie damascus stuff coiled into a cylinder at a red heat, ana men welded together at the seams. The best modern barrels for fowling pieces are con- structed of stub-nail iron in this manner. The slip or fillet is only half an inch broad, or sometimes less, and is left thicker at the end which is to form the breech, an^ h.nner at the end which is to form the muzzle, than in the intermediate portion. Ihis tiiiet being moderately heated to increase its pliancy, is then lapped round the mandril m a spiral dire<.tion till a proper length of cylinder is formed; the edges ^eing made to OTcrla? a little in order to give them a better hold in the weldmg process. The coi C^ 718 FIRE ARMS. FIRE ARMS. 719 m 1^ :,: ^ 539 being taken ofl the mandrU and again heated, is struck down vertically with its mnzzta end upon the anvil, whereby the spiral junctions are made closer and morT un ifoiT ft K now welded at several successive heats, hammered by horizontal strokes, called yimi. tng, and brought into proper shape on the mandril. The finer barrels are made of «m narrower siub-iron slips, whence they get the name of wire twist. On the Cont nen evZtr%rrerLf '' ";"k7'«'!? '''''^'' lengthwise, then coiled spirally n^i Tk w. f- r *u^ ^"^ ^^^/^^ require to be made of thicker iron, and that of the very bes quality, for they would be spoiled by the least portion of scale upon thdr tSebayon^ ' "'" "' '^''^'"^ ^ ^''^' ^' ^^^ °»"^^»'' '^ S^^^ » «^««t holLg to The barrels thus made are annealed with a ppntl«» >»«.o* ;« « ^«-.- r • slowly cooled.. They are now ready for trborerf" s' n Xn^sq^T^.l/o"? steel, pressed m Us rotation against the barrel, by a slip of wood applied to one of t fla sides and held m its place by a ring of metal. The boring bench works horizon! tally, and has a very shaky appearance, in respect at least of th% "^17 some cases however, it has been attempted to work the barrfk nnH h.»., o* - • i" .• '=»ses, horizon of 30^ in order u, Lili.ate .he dt h^^" Vth'e t^ in"s ""Thf ^ Jd i "h'elS u, . slot l^^nly one pom., .0 allow i. l« humor .he B,oveme'n.s of lheli,7er which would otherwise be infallibly broken. The bit, as repre- sented in Jig. 538, has merely its square head inserted into a clamp-chuck of the lathe, and plays freely through the rest of its length. Fig. 539 represents in plan the boring bench for musket „_. „ r • ,. . . barrels; //is the sledge or fnt K^ u I"^ *" '^^"'^ ^^^ ^^''■^' '^ supported; a is the revolving chuck of the lathe, i^;L7 ! .u^ ^''"•^'■^ ^"'^ ''^ *^^ ^'^'-f^^' 538, is inserted ; b is the barrel, clamped at it^ middle to the carnage, and capable of being pressed onwards against the tapering bit of ine borer, by the bent lever c, worked by the left hand of the operative against fulcrum KnoDs at rf, which stand about two inches asunder. Whenever the barrel has been iftereby advanced a certain space to the right, the bent end of the lever is shifted against anoiner knob or pm. The borer appears to a stranser to be a very awkward and unsteady mechanism, but its perpetual vibrations do not affect the accuracy of the bore. The ?™'"." fu^f ""^^ ^^ ""^^ ^"^""^ °^ pentagonal form, and either gradually tapered Irom Its thickest part, or of uniform diameter till within two inches ofthe end, whence It IS suddenly tapered to a point. j^^JsK?!,"^,^'^^ ""^^i*" "^^"^ ^^"^ ^""* * ^^^^^y beginning with the smallest and end- ing with the largest. But this multiplication of tools becomes unnecessary, by laying agBinst the cutting part of the bit slips of wood, called spales, of gradually increasing inickness, so that the edge is pressed by them progressively further from the'axis. The Dore IS next polished. This is done by a bit with a very smooth edge, which is mounted as above, with a w-dge of wood besmeared with a mixture of oil and emery. The inside IS finished by workm? a cylindrical steel file quickly backwards and forwards within it. wniie It IS revolving slowly. ' In boring, the bit must be well oiled or greased, and the barrel must be kept cool by llnL/^ ^'■"'^1^ T 'i ' ^°'' ^^^ ^''^' revolving at the rate of 120 or 140 times a minute, fw «o?-* f^^^ ^^^1 9^ ^^^^' ^^ * ^«^ ^^ detected in the barrel during the boring that part is hammered in, and then the bit is employed to turn it out. f\,^^J sportsmen are of opinion that a barrel with a bore somewhat narrowed towards J^,.r^^ 1 ^V^^ ^° ^^^P ^^^^ ^^"^^ together; and that roughening its inside with pounded glass has a good effect, with the same view. For this purpose, also, fine spiral ZZ^ 7 f"! T^^ :," '^f'' •"'"'••«' ^"•■^«*=^- The justness of its calibre is tried by ^.>^?nn h.VL" I -r"^ 'y^'"'^"'' ^^ '*""'' 3 ""' ^ '"^^^^ '«"^' ^hich ought to movc without friction, but with uniform contact from end to end of the barrel. Whatever irregularities appear must be immediately removed. The outer surface of the barrel is commonly polished upon a dry grindstone, but it is Jl^ritiTK ' "^ less dan-eTously to the workman, at a turning lathe with a slide rest, into Ih" h ^u ^^- ' ' "^A^i ^^ T^^ *° '■^^^'^^ «t the mouth of a tunnel of some kind, moL ninth ' r fh* ^T^ u'l"^^* '^ '."'■y ""^ '^^ ferruginous particles. A piece of moist cloth or leather should be suspended before the orifice Rifle barrels have parallel grooves of a square or angularVorm cut within them, each groove being drawn in succession. These grooves run spirally, and form each an Vl^a^-^A ?A^ revolution from the chamber to the muzzle. Rifles should not be too deeply indented; only so much as to prevent the ball turning round within the barrel. and the spires should be truly parallel, that the ball may glide along with a regular pace. See infra. The Parisian gun-makers, who are reckoned very expert, draw out the iron for the barrels at hand forges, in fillets only one ninth of an inch thick, one inch and a half broad, and four feet long. Twenty-five of these ribands are laid upon each other, between two similar ones of double thickness, and the bundle, weighing 60 pounds, bound with wire at two places, serves to make two barrels. The thicker plates are intended to protect the thinner from the violence of the fire in the numerous successive heats neces- sary to complete the welding, and to form the bundle into a bar two thirds of an inch broad, by half an inch thick ; the direction of the individual plates relatively to the breadth being preserved. This bar, folded flat upon itself, is again wrought at the forge, till it is only half an inch broad, and a quarter of an inch thick, while the plates of the primitive ribands are now set perpendicular to the breadth of the narrow fillet ; the length of which must be 15 or 16 feet French (16 or 17 English), to form a fowling piece from 28 to 30 inches long. This fillet, heated to a cherry red in successive portions, is coiled into as close a spiral as possible, upon a mandril about two fiAhs of an inch in diameter. The mandril has at one end a stout head for drawing i out, by means of the hammer and the grooves of the anvil, previous to every heating. The welding is performed upon a mandril introduced after each heat ; the middle of the barrel being first worked, while the fillets are forced back against each other, along the surface of the mandril, to secure their perfect union. The original plates having in the formation of the ultimate long riband become very thin, appear upon the surface of the barrel like threads of a fine screw, with blackish tints to mark the junctions. In making a double-barrelled gun, the two are formed from the same bundle of slips, the coils of the one finished fillet being turned to the right hand, and those of the other to the left. The Damascus barrels forged as above described, from a bundle of steel and iron plates laid alternately together, are twisted at the forge several times, then coiled and welded as usual. Fifteen Parisian workmen concur in one operation : six at the forge ; two at the boring mill; seven at filing, turning, and adjusting; yet all together make only six pairs of barrels per week, which are sold at from 100 to 300 francs the pair, ready for putting into the stock. the common ; the chamber, plug, or mortar. Jig. 540 ; and the patent. Jig. 541. The common The breeching is of three kinds : 541 was formerly used for soldiers' muskets and inferior pieces. The second is a trifling improvement upon it. In the patent breeching, the screvirs do not in- terfere with the touch-hole, and the ignition is quicker in the main chamber. The only locks which it is worth while to describe are those upon the percussion principle, as flint locks will certainly soon cease to be employed even in military muskets. Forsyth's lock (Jig. 542) was an ingenious contrivance. It has a maga- zine a, for containing the detonating pow- der, which revolves round a roller 6, whose end is "fecrewed into the breech of the barrel. The priming powder passes through a small hole in the roller, which leads to a channel in communication with the chamber of the gun. The pan for holding the pninmg is placed immediately over thelitt.e hole in the roller. There is a steel punch c, in the magazine, whose under end stands above the pan, ready :M 720 FIRE ARMS. r» ^ to ignite the priming when struck upon the top by the cock rf, whenever the trigger it drawn. The punch immediately aAer being driven down into the pan is raised by the action of a spiral spring. For each explosion, the magazine must be turned so far round as to let fall a portion of the percussion powder into the pan ; after which it is turned back, and the steel punch recovers its proper position for striking another blow into the pan. The invention of the copper percussion cap was another great improvement upon the detonating plan. Fig. 543 represents the ordinary percussion lock, which is happily divested of three awkward projections upon the flint lock, namely, the hammer, hammer spring, and the pan. Nothing now appears upon the plate of the lock, but the cock or striking hammer, which inflicts the proper blow upon the percussion cap. It is concave, with a small metallic ring or border, called a shield or fence, for the purpose of enclosing the cap, as it were, and preventing its splinters doing injury to the sportsman, as also protecting against the line of flame which may issue from the touch-hole in the cap nipple. This is screwed into the patent breech, and is perforated with a small hcle. 543 The safety lock of Dr. Somerville is a truly humane invention. Its essential feature is a slide stop or catch, placed under the trigger a, Jig. 544. It is pulled forward into a notch in the trigger, by means of a spring b, upon the front of the guard, which is worked by a key c, pressing upon the spring when the piece is discharged. In another safety plan there is a small moveable curved piece of iron, a, which rises through an opening B, in the lock-plate c, and prevents the cock from reaching the nipple, as represented in the figure, until it is drawn back within the plate of the lock when the piece is fired. 544 To fire this gun, two different points must be pressed at the same time. If by accident the key which works the safety be touched, nothing happens, because the trigger is not drawn ; and the trigger touched alone can produce no eflfect, because it is locked. The pressure must be applied to the trigger and the key at the same instant, otherwise the lock will not work. The French musket is longer than the British, in the proportion of 44*72 inches to 4S but the French bayonet is 15 inches, whereas the British is 17. FIRE ARMS. Eng. Dimeniiont. Diameter of the bore - - - - 0.75 in. Diameter of the ball ... - 0'676 Weight of the ball in oz. - - - 1-06 Weight of the firelock and bayonet in lbs. - 12*25 Length of the barrel and bayonet - - 59*00 Within these few j'ears a great many contrivances have been 721 Ft. Dimensi 0*69 in. 0-65 0*958 10*980 69*72 brought forward, and several have been patented for fire arms. The first I shall notice is that of Charles Random, Baron de Berenger. Fig. 545 shows the lock and breech of a fowling piece, with a sliding protector on one of the improved plans ; a is the hammer, b the nipple of the touch-hole, c a bent lever, turning upon a pin, fixed into the lock-plate at d. The upper end of this bent lever stands partly under the nose of the hammer, and while in that situation stops it from striking the nipple. A slider g / A, connected with the under part of the gun-stock, is attached to the tail of the bent lever at »; and when the piece is brought to the shoulder for firing, the hand of the sportsman pressing against the bent part of the slider at g, forces this back, and thereby moves the end of the lever c forward from under the nose of the cock or hammer, as shown by the dotted lines. The trigger being now drawn, the piece will be discharged ; and on removing the hand from the end g, of the slider /, the spring at h acting against the guard, will force the slider forward, and the lever into the position first described. Mr. Redford, gun-maker of Birminghan, proposes a modification of the lock for small fire-arms, in which the application of pressure to the sear spring for discharging the piece is made by means of a plug, depressed by the thumb, instead of the force of the finger exerted against the trigger. Fig. 546 represents a fowling piece partly in 546 -^^ section. The sear spring is shown at a. It is not here connected with the irigger as Uk other locks ; but is attached by a double-jointed piece to a lever 6, which turns upon a fulcrum pin in its centre. At the reverse end of this lever an arm extends forwards, like tjat of an ordinary sear spring, upon which arm the lower end of the plug c is intended to bear; and when this plug is depressed by the thumb bearing upon it, that end of the lever b will be forced downwards, and the reverse end will be raised, so as to draw up the end of the sear spring, and set oflf the piece. For the sake of protection, the head of the plug c is covered by a moveable cap d, forming part of a slider €, which moves to and fro in a groove in the stock, behind the breech end of the barrel ; this slider e is acted upon by the trigger through levers, which might be attached to the other side of the lock-plate ; but are not shown in this figare, to avoid confusion. When the piece is brought to the shoulder for firing, the fore-finger must be applied as usual to the trigger, but merely for the purpose of drawing back the slider «, and uncovering the head of the plu? ; when this is done, the thumb is to be pressed upon the head of the plug, and will thus discharge the piece. A spring bearing against the lever of the slider e, will, when the finger is withdrawn from the trigger, send the slider forward again, and cover the head of the plug, as shown. It is with pleasure I again advert to the humane ingenuity of the Rev. John Somerville, of Currie. In April, 1835, he obtained a patent for a further invention to prevent the accidental discharge of fire arms. It consists in hindering the hammer from reaching the nipple of a percussion lock, or the flint reaching the steel of an ordinary one, by the interposition of moveable safety studs or pins, which protrude from under the false breech before the hammers of the locks, and prevent them from descending to strike. 722 FIRE ARMS. FIRE ARMS. 723 I I These safely stads or pins are moved ont of the way hy the pressure of the right hand ol the person using the gun only when in the act of firing, that is, when the force of lh« Tight hand and arm is exerted to press the butt end of the stock of the gun against the shoulder while the aim is taken and the trigger pulled. In carrying the gun at rest, the proper parts of the thumb or hand do not come over Mr. Somerville's moveable buttons or studs. Fig. 547 is a side view of part of a double percussion gun ; and fig, 548 is a lop or plan view, which will serve to explain these improveraenls, and show one, out of many, methods of carrying them into effect. a is the stock of the gnn; b the barrels; c the breech ; d the nipples ; e the false breech, on the under side of which the levers which work the safety studs or pins are placed ; f is the shield of the false breech; g, triggers; H the lock-plate ; and i the hammers : all of which are constructed as usual : a a are the safely studs or pins, which protrude before the shield f, and work through guide pieces on the under side of the false breech. The button piece is placed in the position for the thumb of the right hand to act upon it ; but when the pressure of the ball of the right thumb is to produce the movement of the safety studs, it must be placed in or near the position k ; and when the heel of the right hand is to effect the move menu of the safety studs, the button piece must be placed at l, or nearly so. 548 - - 549 In these last two positions, the lever (which is acted upon by the button piece to work the safety studs through a slide) would require to be of a different shape and differ- ently mounted. When the hammers are down upon the nipples after discharging the gun, the ends of the safety pins press against the inner sides of the hammers. When this invention is adapted to single-barrelled guns, only one pin, a, one lever and button piece will be required. Mr. Richards, gun-maker, Birmingham, patented, in March, 1836, a modification of the copper cap for holding the percussion powder, as represented fig. 549 ; in which the powder is removed from the top of the cap, and brought nearer the mouth ; a being the top, b the sides, and c the position of Ihe priming. The dotted lines show the direc- tion of the explosion, whereby it is seen that the metal case is opened or distended only in a small degree, and not likely to burst to pieces, as in the comnion caps, the space between a and c being occupied by a piece of any kind of hard metal d, soldered or other- wise fastened in the cap. George Lovell, Esq., director of the Royal Manufactory of Arms at Enfield, has re- cently made a great improvement upon the priming chamber. He forms it into a verti- cal double cone, joined in the middle by the common apex ; the base of the upper cone being in contact with the percussion cap, presents the most extensive surface to the ful- minate upon the one hand, while the base of the under one being in a line with the inierior stkiface of the barrel, presents the largest surface to the gunpowder charge, upon the other. In the old nipple the apex of the cone being at its top, afforded very injudiciously the minimum surface to the exploding force. Guns, Rifling of the Barreh. — The outside of rifle barrels is, in general, octagonal, AAer the barrel is bored, and rendered truly cylindrical, it is fixed upon the rifling machine. This instrument is formed upon a square plank of wood 7 feet long, to which is fitted a tube about an inch in diameter, with spiral grooves deeply cut internally through its whole length; and to this a circular plate is attached, about 5 inches diameter, accuralAy divided in concentric circles, into from 5 to 16 equal parts, and ■upported by two rings made fast to the plank, in which rings it revolves. An arm connected with the dividing graduated plate, and pierced with holes, through which a pin is passed, regulates the change of the tube in giving the desired number of grooves to the barrel. An iron rod, with a moveable handle at the one end, and a steel cutter ia the other, passes through the above rifling lube. This rod is covered with a core of lead one foot long. The barrel is firmly fixed by two rings on the plank, standing in a straight line on the tube. The rod is now drawn repeatedly through the barrel, from end to end, until the cutter has formed one groove of the proper depth. The pin is then shifted to another hole in the dividing plate, and the operation of grooving is repeated till the whole number of riflings is completed. The barrel is next taken out of the machine, and fin- ished. This is done by casting upon the end of a small iron rod a core of lead, which, when besmeared with a mixture of fine emery and oil, is drawn, for a considerable time, by the workmen, from the one end of the barrel to the other, till the inner surface has become finely polished. The best decree of spirality is found to be from a quarter to half a revolution in a length of three feet. Military Rifles.— An essential improvement in this destructive arm has lately been in- troduced into the British service at the suggestion of Mr. Lovell. The intention in all rifles is to impart to the ball a rotatory or spmning motion round its axis, as it passes out through the barrel. This object was attained, to a certain degree, in the rifles of the old pattern, by cutting seven spiral grooves into the inside of the barrel, in the manner shown by Jig. 550, the spherical ball, fig. 551, being a little 663 552 550 551 larger than the bore, was driven down with a mallet, by which the projecting ribs were forced into the surface of the ball, so as to keep it in contact with their curvatures, during its expulsion. Instead of this laborious and insecure process, the barrel being now cut with only two opposite grooves, fig. 552, and the ball being formed with a projecting belt, or zone, round its equator, of the same form as the two grooves, fig. 553, it enters so readily into these hollows, that little or no force is required to press it down upon the powder. So much more hold of the barrel is at the same time obtained, that instead of one quarter of a turn, which was the utmost that could be safely given in the old way, with- out danger of stripping the ball, a whole turn round the barrel,' in its length, can be given to the two grooved rifles; whereby a far more certain and complete rotatory motion is imparted to the ball. The grand practical result is, that better practice has been per- formed by several companies of the Rifle Corps, at 300 yards, than could be produced with the best old military rifles at 150 yards; the soldier being meanwhile enabled to load with much greater ease and despatch. The bell is bevelled to its middle line, and not so flat as shown in the figure. This mode of rifling is not, however, new in England. In fact, it is one of the oldest upon record ; and appears to have fallen into disuse from faults in the execution. The id^ was revived within the last few years in Brunswick, and it was tried ia Mr. LoveWs Lode, Hanover also, but with a lens-shaped (Linsenformig) ball. The judicious modifications and improvements it has finally received in Mr. Lovell's hands, have brought out all its i !' 1 I it I I 724 FIRE ARMS. advantages, and rendered it, when skilfullj used, a weapon of unerring aim, even at the prodigious distance of TOO yards. The locks, also, for the military service generally, are now receiving an important im- provement by means of his labors, having been simplified in a remarkable manner. The action of the main spring is reversed, as shown hjfig. 554; thus rendering the whole mechanism more solid, compact, and convenient; while the ignition of the charge being effected by percussion powders in a copper cap, the fire of the British line will, in future, be more murderous than ever, as a miss-fire is hardly ever experienced with the fire-arms made at the Royal manufactury, under Mr. Lovell's skilful superinten- dence. Barrel-welding hy Machinery. — ^The barrels of musquets, birding-guns, Ac, or what are called plain, to distinguish them from those denominated stub or twisted barrels, have of late years been formed by means of rolls, a process in which the welding is first effected on a short slab of thick iron, and then the barrel is brought down to its destined length, and form, by repeatedly passing it between a pair of rolls, that have been previously grooved to the exact shape of the barrel intended to be made. This method has entirely superseded the skelp-welding by hand described in the Vic. of Man., p. 471, and is conducted as follows : — The iron being thoroughly refined, and reduced into flat bars by the process de- scribed at length at p. 705, is cut by the shears into slabs or lengths of 10 to 12 inches, and 10 to 10| lbs. weight, or less, according to the description of gun-barrel that i« intended to be made. These slabs are then heated, and bent in their whole length, bj means of conveniently grooved bending rolls, until they assume the form of rough tubes, 555 of the kind of section shown by Affig. 5.55. They are then placed c*. thf O hearth of the reverberatory furnace {Did. p. 701), and brought to a AiJ welding heat, and as soon as the edges of a tube come to a semi-fluid states it is taken out and passed between rolls having grooves somewhat smallet in diameter than the exterior of the tube, by which means the tuba is perfectly welded from end to end ; and if care be taken in the management of the heat, and the juncture be kept clear of dirt and cinders, the iron will be found perfectly homogeneous in every part, and there will be no appearance whatever of the seam where the edges came together. These lubes are repeatedly heated, and passed between the barrel rolls, which are of sufficient diameter to admit of gradually decreasing grooves, the whole length of the intended barrel being indented on their surfaces. To preserve the tubular form, and insure regularity in the size of the bore during the welding process, they are taken out of the furnace, bv thrusting into them a tool called a mandril b, which consists of a long rod of iron, havmg a short steel treblett on its end, of the diameter that the bore of the barrel is meant to bore. This rod is so adjusted by means of a strong iron plate c, near its handle, which is of wood, and long, that when passed with the heated tube on it between two tranverse holding bars, the thort steel treblett d, shall be found exactly between the point of impact of the barrel- rolls, £ E. 556 B The adhesion of the hot iron to the surface of the rolls is strong enough to draw th« tube off the mandril, which thus keeps the bore open from end to end, and by repeating the process through the whole series of grooves in the rolls, the barrel is gradually elongated, and brought down to the exact form required : any superfluous length at the muzzle is then cut off. The breach end is then adjusted by the hammer — a tripple-seat welded on by hand if' it be intended for a percussion lock, and then the barrel is ready lo go forward to the mill to be bored, turned, and finished. Gun-barrels formed by this mechanical method are found to stand proof better than (hose worked by hand, because the heat is more equalized ; and any imperfections in the original mass of iron are more dispersed over the whole extent of the tube. Mr. Wells Ingram, of Bradford street, Birmingham, has lately perfected a very com- plete lathe for turning the exterior of gun-barrels of all descriptions, a process which is FIRE ARMS. 725 fast superseding the use of the grindstone, for equalising the barrels of all kinds of fire- arm& I am indebted for this article to Mr. Lovell, Director of the Royal Arms Manufactory. See MusQUET. Since the first edition of the Dictionary large strides have been made towards in- creasing the efficacy of military fire arms; the French had found in their skirmishes with Abd-el-Kader in Africa, that the long matchlocks of the Arabs told at fearful odds against their men at distances where the ordinary French musquet was powerless of ofifence. After a while it was found that this increased range was due solely to the greater elevation taken by the natives in aiming, and their expertness in judging their dis- tances, taught by long practice and experience ; for the Arab arms and ammunition taken at Constantine were found of the rudest construction. These observations led the French officers of artillery to institute all sorts of experi- ments to render their small arms more effective ; by the adoption of wall-pieces of wider bore ; by introducing a more general use of rifled barrels, but at the same time avoiding the tedious method of loading by means of mallets formerly observed with such kind of arms. The first attempt towards such object was that proposed by M. Delvigne, an oflSeer of the royal ex-guard, {fg, 557), in which the upper orifice of the chamber that contained the powder took the form of a cup, wherein the ball (somewhat wider in diameter) was received, and by two or three smart blows of a heavy-headed rammer (also cupped out for the purpose) became expanded latterly, and thus the rotary motion was imparted to it by the spiral grooves of the barrel in passing out Colonel Poncharra suggested the addition of a wood bottom or sabot under the ball and a greased woollen patch; and Colonel Thouvesino proposed (fg. 568) a steel stem or pillar about 2 inches 558 long inserted into the face of the breech-pin; round this pin, the charge of powder was received, and the diameter of the ball, when resting on the top of the pin was enlarged by the blows of the heavy-headed rammer, as suggested by Delvigne. This system took the name of " Carabine 4 Tige," and has been very generally intro- duced for the service of fusilier battalions in continental armies; very grave objections, however, have been found against it in use, from the impossibility of keeping the chamber (or post round the pin) clear ; and from the severe labor to the soldier in ramming down and enlarging the diameter of the ball sufficiently to ensure the rotary motion desired. But if the ultimate results thus attained with spherical balls turned out not entirely satisfactory, it was made clearly manifest, in the course of the experiments carried on, that no insuperable diflSculty stands in the way of rendering the fire of infantry very much more accurate and powerful, by the use of rifled barrels throughout the army, and thus leading to a verification of the prediction made by Robins above one hundred years ago, that " whatever state shall thoroughly comprehend the nature and advan- tages of rifled barrel pieces, and having facilitated and completed their construction, shall introduce into their armies their general use, with dexterity in the management of them, will by this means acquire a superiority which will almost equal any thing that has been done at any time. But besides smoothing the way to such an essential improvement, it has been elicited of late years, that when the accuracy of flight is secured by the rotary motion derived from the rifling, the bullet, instead of being limited to the form of a sphere as hereto- fore, may, up to certain limits, be elongated with considerable increase of destructive ef- fect; and with an augmentation of range very much beyond anything that has hither- to been considered to lie within the reach of small arms — placing them, in fact^ with reference to artillery and cavalry, in the first place instead of the last. An immensely extended field has thus been opened to experimenters. Ist Mons. Didon proposed a true oval {fg. 659) as the best form of bullet^ so that when shortened by the blows of the heavy rammer and widened in its diameter it might be brought nearer to the spherical shape before leaving the barrel. 726 FIRE ARMS. ( ■ f. Delvigne took a patent for a bullet {fig. 560) under the designntion of ;ivale;" it had a conical opening behind, in which he imagined tliat ihe owder would exert itself with sufficient energy to expand the lead perma- 2d. Mons. Deb " Cylindro Ogivale" lorce 01 iiie powder nuuiu v-a^iv iwv^ji mvuouiiiuicub cuciiiy tv cauouvi mc itov* j/tin.w nently, and so make the ball take the rotary movement derived from the rifling, with- out any fatigue to the soldier in loading; with this projectile, indeed, the operation ia but slightly more difficult than with the ordinary cartridge and smooth barrels. } H The bullet {fig. 661) of the " Carabine k Tige" was called " Cylindro Conique," and was said to possess this advantage over the preceding, that, being brought more to a point in front, it bored its way through the air with greater ease, and thus retained greater velocity, and of course more extended range; and with this bullet it was that Mons. Tamisier introduced three sharp-edged channels round it, which he stated were necessary to keep its flight steady, by ofi'ering a resistance to the action of the air. Finally Mons. Minie, anofficer of the French line, suggested {fig. 562) the addition of a denoyau or culot to the hollow ball of Delvigne. This, in the form ot a little cup made of sheet iron, is placed in the orifice of the conical hollow of the ball behind, and by the enei^y of the powder is driven into the ball, enlarging its diameter permanently, and thus giving all the accuracy of the rifle, with nearly the same facility of loading as with the plain barrel. The principle of the invention, as thus developed, has, we learn, been adopted by our government for the general use of the army, seeing that it offers so great advantages over the system of plain barrels, but the bullet {fig. 663), as modified by the Inspector of Small Arms, has on its exterior no channels, they being found not only useless as to steadying the flight of the projectile, but absolutely injurious in lowering its velocity. The bulletin its improved form, too, being more truly balanced in its proportions, and made by mechanical means instead of by casting, has no tendency to the gyrations which appear to have so puzzled French artillerists, and for which they have invented the word " derivation," and wasted much learned disquisition. Though well satisfied with the results of their course of experiments, our neighbors, however, do not appear to have come to any final decision as yet ; indeed, the fact of being able to make use of an elongated projectile with a rifle has let loose such a crowd of inventors, that they seem to be entirely bewildered. In Switzerland every Canton has its peculiar form of bullet, each one, of course, being the best, and from the length and size of a small caterpillar upwards, every man seems to have his own maggot, which he vaunts before the world. But even if it were ever to happen, which is not likely, that these various projectors could be brought to agree as to the best form of projectile, they will then find out, that although by the general introduction of rifled and elongated bullets an immense advantage has been realised over plain barrels, their plans, based as they all are upon a system of loading at the muzzle, are at best but one step in advance ; and that a good sound military fire-arna loading at the breech will, after all, remain the great desidera- tum — an arm that, without any less accuracy or power to reach masses of artillery or cavalry at a thousand yards' distance, will enable the soldier to triple the quantity of his fire at any moment that he may be called upon to repel a charge of cavalry or at tack or defend a breach at close quarters ; of such simple construction, and so easily handled in every position of the body, that the soldier can pour every shot of his most murderous fire upon the enemy with unerring precision, whilst he himself may lay coolly behind a stone or in a ditch in entire security. These are no longer wild imaginings, although so many hundreds of attempts towards the same object, from the earliest period to the present day, have been one a'ter another seen invariably to fail. The Germans have been long and steadily pursuirg the great object, until at length Herr Dreysa, of Sommerda in Thuringia, has succeeded, after more than twenty years of continued labor, in establbhing a musquet, under the name FIRE-WORKS. 727 of "Ziindnadelg^wehr," which if not quite perfect, has been found to work so well in the hands of the men, that the Prussian government has already 80,000 in possession, and they are going on to arm the whole of their line regiments and Landwehr with them. Even with the assistance of a diagram, it is hardly possible to convey a clear notion of the construction of this musquet, because the several parts work one within the other, and their combination, which is without pin or screw, is hard to comprehend by a mere description. There is a strong socket, fig. 564), a, open on the upper side, screwed on to the barrel, 664 665 6, which is rifled in the usual manner ; within this socket is a slider c, which in fact constitutes the lock, as it contains the spiral spring and mechanism that produces ignition by percussion ; it has a stout hebel or handle, by which it is moved backwards and forwards freely. The cartridge {fig. 665) consists of the ball a, the sabot 6, or bottom of hard paper, and holding the priming matter, and lastly the charge of powder, c, the whole being made up in paper pasted together. In use, the slider being drawn back, the soldier puts the cartridge with the point of the ball in front into the open breech of the barrel, pushes the slider forward, and secures its close junction by a turn to the right against an inclined edge of the open socket The spiral spring is then brought into action (or the gun is cocked) \>j pressing the spring case forward with the thumb. On pulling the trigger, the interior needle, from which the musquet takes its name, is darted forwai'd through the charge of powder into the percus- sion primer in the sabot, and thus efi\icts the ignition inside the barrel The principle of loading at the breech carries with it so many other advantages beyond that by the muzzle, that many ingenious men are oc- cupying themselves with its improvement; Lefaucheur and Robert in France; Montigny in Belgium ; Kufahl Schultz and Friedrix in Prussia; Sears and Needham in England, have lately brought forward various plans; and now that the idea is taken up upon a right base, there can be little doubt that eventually a system will be hit upon, that shall secure all the requisites for military service, and avoid all objections. But it is clear, from the recent publications on gunnery and the observations of ancient warriors, that the advocates for heavy battalion movements, for drawing up their infantry in long lines and compact bodies for destruction by artillery, will be with difficulty brought to look with patience upon the scrambling and desultory sort of warfare which the general introduction of these improved rifles must bring about Time, however, daily goes on to work wonders upon prejudice, and the day will come when it will be found that cross-belts and blank-cartridges may be abolished without utter ruin to the army ; and that men behind trees, with effective weapons in their hands, may be more dangerous enemies, at long ranges, than when strapped up and paraded out in masses, and carrying arras that at any distance over 300 are powerless of oflFence. FIRE-DAMP ; the explosive carburetted hydrogen of coal mines. See Pftcoal. FIRE- WORKS. {Feux d'artifice, Fr.; Feuerwerke, Germ.) The composition of luminous devices with explosive combustibles, is a modern art resulting from the dis- covery of gunpowder. The finest inventions of this kind are due to the celebrated Ruggieri, father and son, who executed in Rome and Paris, and the principal capitals of Europe, the most brilliant and beautiful fire-works that were ever seen. The following description of their processes will probably prove interesting to many of my readers. The three prime materials of this art are, nitre, sulphur, and charcoal, along with filings of iron, steel, copper, zinc, and resin, camphor, lycopodium, tji dG attention required, never came into such general operation as to supersede entirely hand-dressing, either from their own defects or prejudices against their employment About the year 1830, in consequence of the new mode of spinning, hereafter to be de- scribed, being carried on with considerable energy, it was found advantageous to cut the flax into 2, 3, or more lengths previously to heckling, which rendered it necessary to have machines peculiarly adapted for this new short description of material. This machine, known as the excentric or circular machine, deserves considerable attention for its own inherent merits, and the extensive utility it has proved to be of in suggesting the principal parts of those by which it has been sufiplanted. In its original form it was made of a breadth suitable for only one strick, and consisted of a cylinder 3 ft diameter, upon the whole circumference of which at intervals of 3 or 4 inches were fixed the heckles. As each machine could only carry one description of heckle, it was neces- sary to employ a series of these machmes, called a " class," when the flax reauired to be dressed over a succession of finer tools, each succeeding machine carrying a finer tool than its predecessor. The heckles were cleared of tow by coming in contact at one part of their revolution with a brush roller, which also revolved in contact with a cylinder covered with card clothing, the points of the pins being in such a direction as to clear the brush from tow, and allow itself to be in its turn cleared by the oscillations of a comb, whence by rollere the tow was brought into a sliver. In order to preserve the continuity of the supply of tow, and maintain the regularity of the sliver produced by it, the holders with the flax were presented to the heckle cylinder in a manner peculiar to this machine,and in endless succession by means of certain circular carriers placed at each end of the heckle cylinder, but excentric thereto, and at such a distance apart as each should bear one end of the holder as it extended across the cylinder parallel \IU FLAX. 745 to its axle. Thus, the holders introduced at that part of the circumference of these carriers furthest from the heckles were carried forward, while the flax was in opera-* tion, till they were brought almost into contact with the points of the pins, when by the intervention of a slide they were withdrawn from the machine, but with one side only of the flax dressed, and that but on one tool ; therefore, the holder required replacing in the same machine, in order that the second side of the strick should be dressed as was the first The holders then required to be carried by hand to each succeeding machine of the class. The preceding figure (589.) shows the leading features of these machines: A A {Jig. 589.) heckle cylinder; bb excentric wheel to carry holders in its recesses hj h, Jiy h^h,; slide upon which the holders were laid so as to fall into the recesses h, hoi wheel b ; x> slide for taking out holders ; e brush cylinder with brushes ; g cylinder covered with card clothing ; h holder come out ; i doffing comb. The space of the holder carrying wheel was filled with holders, and so maintained in endless succession, and thus each served in some measure to keep the end of its preceding one down into the heckles. About 1833, a machine was patented consisting of two parallel cylinders, over which the flax was carried, revolving in its progress so as to present the alternate sides of the strick to the heckles, the progressively finer tools being ranged along these cylinders, so that having passed the length of one cylinder one end was completely finished. "When the holder was taken out, " shifted," and replaced, it was carried back along the second cylinder, and thus returned to where it conmienced, finished. This machine, however, never was carried further than the experimental one for the patent Another machine the same year made its appearance, and which for some time en- joyed much celebrity. It consisted of two parallel vertical sheets of heckles running together, and so geared that the heckles of one intersected the interstices of the other. The flax suspended in its holder from a species of trough passed between these two sheets, and was thus heckled simultaneously on each side in its course through the progressively finer heckles from one end of the machine to the other. A, A (690.) heckle sheets ; b b holder trough or slide ; c, c; c, c, pulleys for carrying the heckle sheets ; n, d brush rollers ; k, e rollers covered with card clothing to clear the brushes ; f, f doffer combs ; g, g, g, g heckles ; h holder ; i, i brushes. At about the same period a foreign machine was patented, known as Evans's ma- chine, of which the following description will give a correct idea of its principle of action, and also of its holders, which are different from those already described. Vol. L 2 a Y46 FLAX There are two series of combs, see^igr. 691., attached to two movable frames represented "^ """ ~ at a and 6. Each frame is formed by vertical bars a 6, with lateral branches or arms, which carry the heckle points. The branch- es or arms are parallel, and at equal dis tances apart, but fixed in such positions in gggCach frame that they may occupy the inter- vening space when the frames are brought together a^Jig. 592. The frames are put in motion by means of revolving cranks to which they are attached as shown in /«. 692., and when the cranks turn upon their axes, the branches of one frame pass be- tween those of the other without touching. This forms what may be called a set of \^-„ 3 . ^1 . „ , combs ; the points of the combs of one set bemg opposed to the pomts of the combs in the other set. «l,nw« ^^l^"" ^}^''^^- *^^«e"es of combs that compose one set act upon the flax, is shown m the side view /^r. 591. When the cranks are nearly verticaVUie pobt^of both frames are away from the flax, but as the cranks move roUd in the dfreTon of he:klTo?one of t^ ^r"' ''i' ^"^.'^^^ P^^^^^^"' ^"^ '' '^ ^^^ thIrtheToln" or or XTde itrfiw! 5?°^"%^,^^^^^*^, penetrate the flax, and descending they comb or divide its fibres. The rotation of the cranks continuing, the two frames a and h tr flaTand' tCe'o? ^T ^'^f ' ''''^ ^^^P°^^^« «^ ^^^ ^^^^ a w'thra^ing w' tne flax, and those of the frame b approaching and pushing the fibres off from the T w'-i^^'^ ^'l °^^ '^"^^^^ ^y the descending stroL of the pointe. «/J .u "'^'^ ^f P^^^^e^ved that as the combs of the frame a and h respectively ^:t.^Ti^V^^ however, of such combs or heckles acting only on one side of the flax would but imperfectly perform the operation of opening its fibres ; it is therefore tZT^' '? ^'?'' ^l accomplish the desired object in the most eft^ctual way that strick of fl'!l' '^ '''"!?7' \r^'' ^^^^^^ ^' ^^^i^* *« ^'' «" opposite sid^s^'f the stnck of flax, suspended in the position shown in the figures. The cranks of the two ffi't l'*'i^^ <^o«^b-frames or heckles a, b, and c, /are connecS^i by a pafr^f IctiaLd'at'ot:' (Cl^'- T" "'-^^ ^^"'' '^^^^^^ "^^^^^' ^y -^i«^ theVec£es are actuated at once, the two sets moving m opposite directions, but with similar speeds Wp wT^'^^f''^ heckling of the material will go on in the way shown T the figxire last indicated. The tow being collected as drawn off the loVer end of the anf de WyVon^^^^^ "'^'"'^ ^^'"^'^^ ^^ '^^^^ ^^^^^' ^^^^ '' '^ ^^^^^ ^J --^ use^' fSZr^Jl^""" ^/^'i considerably from the clamps which are commonly used 1 shall therefore particularly describe their construction, before showing them m operation. Mgs. 694. and 595. are views of the clamp in tVo different pofition^ a and b are two boards united together by a hinge c, at top, which of course allows them to shut and open. The lower parts, forming the jaws of the clamps, are made with teeth or in- dentations, between which parts the ends of the flax or hemp are securely held when the j/ rU^ . /// VV clamps are brought together; d d, are two \?Jrn tly ^^^ i <^ pieces projecting from the board 6, at the end \y ' Y^ *^ of each of which is an eye shown by dots, and Jo « ^^, VI J 1 X . *^ *^® ^^^^ ®^ ^^® board a, (see /cr. 694.) there w a double aimed lever ^, turning upon a fixed pin/, which lever carries two circular wedges g g These wedges pass into the eyes of the pieces d d, when the clamps are closed, and hold them fast. There is a segment ratchet A, at the upper part of the board a, which turns upon a stud i, and is pressed downward by a spring k. This ratchet receives the end of the lever e, and consequently keeps the circular wedges ^nTK'^l t^t^ '^^i'S ^""^^ .^^^ "^^^""P^ securely together, and prevent their open- ing by the shaking of the machine. ^ o . r f ^Z^!'T ' -i^ Wfed to open the clamps, the ratchet A, must be raised, and the lever e pushed aside by its handle I, which draws the circular wedge/ from the eyes of the S «f,! A- 1^/"?/^® ^^ *^^ ''^^'"P^ immediately separate. For the convenience ^r.^i!!^®''^'^^. ® ?^^*^^r^ \° ^^^ machines, a piece of sheet iron m is bent at right angles, and fastened to the back of the board 6, as seen in Jig. 695., forming a groove by means of which the holders are enabled to slide into the machine and hang there. FLAX. '^47 About the year 1840 an improvement took place in the excentric circular, by which one screw of the holder retained two stricks, and the machines made wide enough to take four stricks, and also a movement was made by which the holder was carried over two cylinders, so that each side of the strick was dressed before taking out. These improved machines had a very extensive sale, as wages and the necessity of attention were much reduced by them. Also the third machine, herein-before described, was re- vived, having a rising and falling motion for the holder support, and was known as the Belfast machine ; and similar improvement was made in the double vertical sheet ma- chine. But, as none of these sufficiently dressed the line for the finest jarns, a machine called the " crank machine" was invented for that purpose, but was in use for a very short time ; its object was more to perfect the dressing after the excentric machine than to do the whole work itself. In this machine the flax was suspended, and then stmck simul- taneously on each side by heckles having an al)rupt angular movement, first to strike into, and then draw down the line, in order to draw off the tow ; the work was begun at the end and gradually advanced up to the holder. A, A {Jig. 596.) arms for carrying the heckles; b, b, trough or slide for holders ; c o sliding piece to carry pivots or the carriers a, a, so as to rise and fall by the motion of the bell crank d ; e connection of bell-crank D with excentric f, to give the downward stroke when the heckles are closed upon the flax by the action of the crank, g, connected by arm i with the carrier A ; II holder ; k connecting rod for the carriers a, a ; L and M pivots for the respective carriere a, a ; n, n the heckles. This machine, capable of doing the work but very slowly, and with great expense of heckles, was at- tempted to be improved upon by another made of two parallel cylinders constructed of a series of bars run- ning at equal speeds in contrary directions. Upon these bars were fixed the heckles, which were kept in a horizontal position during their entire revolution, by a crank at the end of each bar, guided in a circular path excentric to that of the bars themselves. The flax sus- pended passed with a rising and falling motion from one emi oi the machine to the other, each succeeding heckle being finer than its preceding. A A {Jig. 597.) circular discs keyed to the shafts b, b ; c, c circular discs running apon the excentric bosses D, d ; e, e heckle bars ; f slide for holders ; o holder. The discs a, a are alike at each end of the machine, and have suitable bearings to carry the heckle shafts e by thdr round necks a, a. The discs c, c have similar and equal number of bearings to carry the cranked ends of the heckle bars c, and arecarrie''''^ '^^'■^^^^ of hanS-work, about 500 kilogramm^ 2..^?^/' ^^'^''l ^'^J^'l' according to the nature of the flax. It is applied with equal advantage to the long or the cut line. It may be conducted or miiaged by FLAX iiSk 4 or 6 children merely, employed to screw and unscrew the clamps (presses), an easy ""^S^wrt^^ton of the machiM,^Fig. 607. longitudinal elevation of the mechanical heckle. ^g. 608. Elevation of one of the sides, or as seen from the end. i, K. Large cylinder, in whose circumference the heckle teeth are fixed. The distanea between the points varies according to the perfection which is desired in the heckling^ 5D2 766 FLAX. FLAX. 757 I :| It and the assist the " gills- ,TXS the fibres • k, L hooked rods to connect the weighted lever A with the hold- L ron^c^and by S; preLsu thus caused insure its effect; dd, the sheet or surface 7" cills" compose^d of separate bars, as seen at^^. 614* 616.* ; e, rubber or cleaner of Dressing rolle^n, /. conductors to contract laterally the sliver at the moment of draw- FnTaXte of metaThaving diagonal openings at an angle of 45° (this plate is sometimes caUeSthf"doS>lkg bars," haling been first made of separate S?""^) ^^ ^^T'^-!?^ couree of the s?i^er, in order to enable it to be turned in a rectangolar direction and gmdcd J^ the delivering rollers h,h ; this direction of the sliver is more distinctly seen at Jig. 6lU i hanger or connector of pressing roller 6 to its weight lever c ; / /, the screws or woroi riiaft for earJp^ng the gill bar «» ">«; consequently the gill depressed i! o 2 ■ f !?• • *^' '*^°"^'" '°'<' "'« ?»«!"«■> « % and drawilg roller, »h^en, oSa cltiniit ttir ^"^ lu"" """'* "•."» »» "='«" *»>« and penetrate the sliier b/the reveSiLwLTnf ?!.'''%"* T'" "'"^^ »» "»« The objection to this infenio JStetrth: t^,::^ottC' :^::t,'^^ 624 Ur^l •"•'.0 ** « F=n V V««^^^'S''w2- '■ "."i'.-"-'.- o • ■' ■=1^ /? o; i^u^e'd a^grtt twtT °' "' ^'"- "^ ''^ ''<""'''= f"""- ''^"--fe. -erature ; b, b, guide rods or pipes to cause the roving to pass under the water. In order to avoid the rollers becoming indented by the roving always passing on the same place, they are caused to traverse the breadth of the rollers by a traversing guide rail, moved by an excentric at the worm apd wheel c; d, flyers, and/, spindles. Here it may be proper to introduce a description of the machines for twisting the yarns when spun into " threads " used for sewing, — ^..Xf- .......jM^^- ,;— ^^.;^ . «_-g;^^, ^,...j^^,^,>>j—^gjf>^-^ ;^^ il c: .M r- J m _r^ 3 ED [H [J] s C±] Q =3 .a rr\ ■97mrf. — m\ — jm — >»¥\=:7^i^=m%. — m/^ — f.J/t lj-a — »>,:x__,,jj\ 1;},^ (^m\ ^^ . ^^ ff,.^ ^.^^.^^ j»>m,.\ cut line machinery for No. 10. 's to 120.'s ; and three systems of tow machinery for No. lO.'s to 40. 's. The building is 56 feet wide and 162 feet long; which is a very suitable and con- venient size, and which admits of the most economical arrangement of the machinery. The following is a df'scription of the machines shown in the preparing room : — A, A, two of Baxter's patent sheet hackling machines for long tow. B, a flax-cutting machine. c, one of P. Fairbairn P -^fUlr- 9 P ve!^^ji»iif^-^M>.^. im\^ m}^.^'M)^ rm^s^/if,^^mif,^^mi/i^-^m,f,^M-^^-Mfi'j,:>..^mMi[ P III. Two systems of three cut line machinery for No. 40.'8 to 120/9 (one for 40.*8 to 70. 'a, and one for 70. 's to 120.'8). 1 flax cutting machine. 1 P. Fairbairn «rt flax, a pair of cylinder heck ng machines were exhibited. The cylinders, instead of being set abreast of each other and acting simultaneously on the flax, are mounted in a line, and revolve m opposite directions, so that the flL is dressed, first on one side by one cylinder, and Xn on the opposite side by the other cylinder. The objection o this arrangement ib. as before indicated, the want of compactness; as machines working on th)S principle Tre 1 eq dred to be double the length ot" those which turn the strick and heckle both side« on the^sar^e heckle-pins, or heckle it simultaneously on both sides. To remedy this ol^ jection, however, MeLs^.awson apply two troughs to the niachme, and arc thj enabled to submit two rows of stricks to the action of the same rotatmg heckle cylinder. Tlie mode oTtraTersTng the flax holders through the machine is analogous to that described S reference to Mr. Plummer's machine, and therefore need not to be repeated. The "ylSs are ?^^^^^^ with two gradesof heckle-pins ; and ^^^ll^-^^^^,^^^^^ aid falling plates (which take their motion from excentrics) are fitted for the purpose of determining the depth that the heckle-pins shall enter the stricks. Between the rows of the finer grade of heckles, small flat brushes being set in one edge of the rising and falling plates form a sort of bed for the flax to lie on while under the action of the heckle& The stricks, in passing over one cylinder, are heckled on one side ; they are then brought under the action of the second cylinder, which, revolving in an opposite direction, will finish the other side of the strick. The machine exhibited by this firm for operating upon long fibres is provided with two endless bands of heckles, set side by Bide, and arranged so as to present an inclined surface to the flax. These bands are set at opposite inclines, and revolve in different directions, for the purpose of operating upon different sides of the stricks of flax. Tliese are the only arrangements of heckling and machinery which the Exhibition contained. It must, therefore, be considered as very deficient in this respect, as the rival inventions of Messrs. Marsden, of Manchester, and Messrs. Combe, of Belfast, for turning the stricks of flax, and causing them to be operated upon on both sides by the same cj^linder (which have recently been the cause of so much litigation) are unrepresented. So also is a still more recent improvement of Messi-s. Combe, for heckling both sides of the strick without turning, by the use of but one cylinder. In this machine (which we have had recently an opportunity of seeing in action at Belfast) the means of operating on both sides of the strick is obtained by merely reversing the direction of rotation of the cylinder, while the trough is ascending to take in a fresh holder. Another arrangement of a promising character, for passing once through the machine, has recently been devised by Messrs. Harding, Cocker, & Co., of Lille; but as this machine was not included m their contribution to the Exhibition, we conclude that it is not yet brought into the market. The flax, after leaving the heckling machine, is slightly combed by hand, and sorted into parcels, according to the quality of the staple ; it is then packed away in a cool, dry, dark room, and by lying there for a i^w months its quality is said to improve. When the flax is taken from the " dressed line store," it is subjected to the action of the following machines, for the purpose of converting it into yarn, viz. ; 1. The first drawing frame, or spreader, the use of which is to convert the flax, as delivered from the heckling machine, into a continuous sliver or band of filaments; 2. The second drawing frame, by which the sliver is attenuated ; 3. The third drawing frame, whereby several slivers from the second drawing frame are united together ^nd redrawn, to obtain a finer sliver, with greater regularity of fibre; 4. The roving frame, which further elongates the sliver, and converts it into a spongy cord or roving; 5. The throstle frame, which extends the spongy or loose roving, and spins it into yarn. The flax drawing frame is very different in construction to that formerly described as employed for drawing cotton, although the action is precisely analogous. Its constructions and mode of operation may be thus briefly described : at the back of the machine is an endless travelling feed- cloth, on which the stricks of flax are laid, so as to overlap each other, and which carries the flax to what are termed the back holding rollers. In front of these rollei-s, and arranged parallel thereto, is a series of " gills " or straight bars furnished with heckle- pins, whose office is to receive the flax as it is delivered from between the holding- rollers, and carry it forward to the drawing-rollers. These gills are supported and traversed by their extremities, taken into the threads of two screw sliafts, set at right angles to the holding rollers, which shafts, as they rotate, carry the gills forward. When they have arrived at the end of the shaft they severally fall, and are received bv a pair of screw shafts below, having a quicker thread, which carry them back to the holding rollers, and a sweep, on the end of these shafts, lifts the gills up again into geer with the upper screw shafts. Thus an endless chain, as it were, of gills is provided, which, having a somewhat greater speed than the holding rollers, combs the flax straight and delivers it with perfectly parallel fibres to the drawing rollers. By these the sliver is drawn to the requisite fineness, and then, passing between a pair of calendering rollers, it is delivered to a can. The cans of sliver, thus produced, are now set up behind the second drawing frame, to undergo the second operation. This frame, and also the third, are similar in construction to the first ; the only difference being,' that they are fed from cans instead of by a cloth ; and as the progress of drawing out the sliver advances, the size of the working parts are required to be less, and the fineness of the gills to be increased. The operation of drawing is the same in all cases ; but in the second and third frames, the sliver is doubled, to give it an evenness, or structural equality, as it is elongated. Messrs. Lawson have exhibited screw gill spreaders (as the first drawing fi-ame is termed) for both long and cut flax; also gill frames for completing the drawing of the long and short fibre, but further than being well made machines, they present no points for comment. Messrs. Higgins lousjop^ ^^ ^^^ ^^^ ^^^ ^^^^ ^^ peat-ashes, Se madTn ^hrburnrnl oTweedsind earth in a smothered fire are a good substitute, those maae D> tne """^""'s . ., gweepines of the streets in towns, mixed with the But the most efl^ective manure ^^^ ^^^^^^ ^^^ ^^^^^^^ t^l'Z^u^^ri^^^^^ - or the seed is trodden in by men, as is done with fine seeds in gardens. This is only in the lightest soils. Most commonly the traineau is drawn over the land. This is a wooden frame with boards nailed closely over it, which is drawn flat over the ground, to level and gently press it In a short time the plants of flax come up thick and evenly, and with them also some weeds. As soon an the flax is a few inches high, the weeds are carefully taken out by women and children, who do this work on their hands and knees, both to see the weeds better, and not to hurt the flax with their feet They tie pieces of coai-se flax round their knees, and creep on with their face to the wind if possible. This is done that the tender flax which has been bent down by creeping over it, may be assisted by the wind in rising. This shows what minute circumstances are attended to by this industrious people. The weeding is repeated till the flax is too high to allow of it The seed which is used is generally obtained from Riga, it being found that the flax raised from home-grown seed is inferior after the first year. But many intelligent men maintain that if a piece of ground were sown thin with linseed, so that the flax could rise with a strong stem and branch out, and if the seed were allowed to ripen, the Flemish seed would be as good as that from Riga ; but it still remains to be proved whether it would be cheaper to raise it or to import it When the flax begins to get yellow at the bottom of the stem, it is time to pull it, if very fine flax is desired, such as is made into thread for lace or fine cambric ; but then the seed will be of little or no value. It is therefore generally left standing until the capsules which contain the seed are fully grown, and the seed formed. Every flax- i ^ 792 FLAX. crower rndges for himself what is most profitable on the whole. The pull ing then be^na, whkh iTdone carefully by small handfuls at a time. These are aid upon he ground to In two and tvvo obliquely across each other. Fine weather is essentjal to this part of^the operation. Soon after this they are collected in the larger bundles, and placed with the root end to the ground, the bundlesbeing slightly tied near the seed end ; the Ither end is spread out that the air may not have access and the ram may not damage the flax When sufficiently dry they are tied more firmly in the middle, and stacked Sloncrnarrow stocks on the ^ouni These stacks are built ns wide as the bundles are long aXabout 8 or 9 flet high. The length depends on the frop: ^hey are Lldomfiade above 20 or 30 feet long. If the field is extensive, several ot these stacks I^e formed at regular distances ; the/are carefully thatched at top, and the ends^which we mi'te perpendicular, are kept up by means of two strong poles driven perpendicularly ^to^ he |roS The^e stacks look from a distance like short mud walls, ^«ch as are ^en in Devonshire. This is the method adopted by those who defer the steeping till Another season Some carry the flax as soon as it is dry under a shed, and take ott the eapsu^^^^^ rippl-g. -l^i<^^ i« drawing the flax through amron comb fixed in a block of wood f the capsSles which are too large to pass between he teeth of ^e comb are thus brokei off an'd fall into a basket or cloth below Sometame^ it the eaosules are brittle, the seed is beaten out by means of a flat wooden bat like a small Set bat The bundles are held by the root end, and the other end is laid on a board Tnd turned round with the left hand while the right with the bat breaks the capsules lid the linseed falls on a cloth below. The flax may then be immediately steeped : but Jhe mo t expelenccd flax-steepers defer this operation till the next season In li^ case it is put in barns, and the seed is beat out at leisure in winter. W hen flax s housed care must^be taken that it be thoroughly dry ; and if the seed is left on -Inch is an advan- t.age to it, mice must be guarded against, for they are very fond of linseed, and would Boon take away a good share of the profits by their depredations. Steeping the^flax is a very important process which requires experience and skill to do it p?operlv The quantity ahd coloir depend much on the mode of steeping, and ie st?eT|th S the fib?e may "be injured by an' injurious mode of f ^forming this o^ra- tion The obiect of steeping is to separate the bark from the woody part of the stem, by dissolv 1^ a glutinous m^attlr which causes it to adhere and -^l\^^'''^rVZZTTa vessels which are interwoven with the l?ngitudinal fibres and keep thojnto^^^^^^^^^ kind of web. A certain fermentation or incipient putrefaction is excited b^ the steeping, which must be carefully watched and stopped at the right time The usual mode of «^eepln" is to place the\undles of flax horizontally in the shallow pool or di ches of .tagnaift water, keeping them under water by means of poles or boards with stones or TefZs laid upon them^. AVater nearly putrid was supposed the most efficacious ; and Te mud is often laid over the flax to accelerate the decomj^osition, but this has been found to s ain the flax, so thatit was very difficult to bleach itor thelmenmadefro^^^^ afterwards. The method adopted by the steepers of Cour ray, where steeping flax is a ktinct trade, is different. The bunies of flax are placed alternately; ^j^^^^^»^;^^^^^^^^^^^ of the one to the root end of the other, the latter projecting a few mches ; as many ot ?hese are tied together near both ends as form a thck bundle -^-fjj^f'l^'^^^^^^^^^ A frame made of oak-rails nailed to strong upright pieces in the form of a box 10 feet square and 4 deep, is filled with these bundles set upright and closely packed. • The lole is then imm^^rsed in the river, boards loaded with stones being Placed upon the flax till the whole is sunk a little under the surface of the water Ihe bottom does not reach the ground, so that the water flows over and under it. There are posts di. ven m the river, to keep the box in its place, and each steeper has a certain portion of the bank which i a valuable property.^ The flax takes somewhat onger tin^yn/eep^^^^ this manner than it does in stagnant or putrid water, and it ,s asserted by tl>ose who adhere to the old method that the flax loses more weight ; but the colour ^^^o much finer, that flax is sent to be steeped in the Lys from every part of Flanders. When it s Bupposed that the flax is nearly steeped sufficiently, which depends on the temperature of the air, the flax being sooner steeped in warm weather than in cold, it ^« '^-^ajnined carefully every day, and towards the latter part of the time several times in the day. m order to ascertain whether the fibres really separate from the wood the whole length of the stem. As soon as this is the case the flax is taken out of the water : even a few hours more or less than is necessary will make a difference in the value of the flax If it is not steeped enough, it will not be easily scutched, and the wood will adhere to it It it has been t^o long in the water, its strength is diminished and more of it breaks "jto tow. The bundles are now untied, and the flax is spread evenly in rows ^^'fpj'^^^j^^'-^^l each other on a piece of clean smooth grass which has been mown or fed off c^os^ ^ine weather is essential to this part of the process, as rain would now much injure the fla^c it is occasionally turned over, which is done dexterously by pushing *\ l«"g ^^^^f^^ J«^ nnder the rows, and taking up the flax neai' the end wkch overlaps the next row and turning it quite over. Thus,' when it is all turned, it ovej'laps as before but in the contra!-y direction. It remains spread out upon the grass for a fortnight, more or less according to the season, till the woody part becomes brittle, and some of the finest fibres ii i i FLAX. 793 separate from it of their own accord. It is then taken up, and as soon as it is quite dry it 18 tied up again in bundles, and carried into a barn to be broken and heckled at leisure during the winter. . .. . The total annual production of flax in Belgium amounts, by a recent estimation, to about forty millions of pounds. Its total value is calculated at about two mimons and a half sterling. This flax is of very superior quality, and is principally emplo) ^^^^ the manufacture of the finest class of fabrics. Attempts are being now made on a large scale to cultivate this important plant in England and Ireland. Belgium exports about five millions of pounds of flax to England. That flax grown in the Courtray district is universally considered to be of the finest quality. Flax Weaving Loom.-a a a. Fig. 648., frame of loom ; b. beam on which he yarn for warp is wound ; c cloth receiving beam ; d driving pulleys and fly-wheel , e hana rail for supporting the reed ; r swords of supports of going part; o picking sticks lor drivine the shuttle ; ii leather straps for connecting the picking sticks with theiF actuating levers l; m, x, jaws of a clamp to cause the retaining friction on the collars of the beam b, by which friction the quantity of weft is regulated ; o end of lever bearing the weight by which the jaws are brought together ; r, lever, keyed at one end to the upright shaft ^ and connected with the other to the fulcrum of the weighted lever o • R lever, one end of which is also keyed to the upright shaft q, and the other is Drovided with a wood sole, and is pressed by a strong spring against the yarn wound Spon the beam b. It will be seen that, as the yarn is taken off the beam b and it« diameter consequently reduced, the lever p moves the tulcrum of the weighted lever o, and thus rec'ulates the pressure upon the clamps m and n, causing an equal tension UDon the vam from the full to the empty beam ; a treddles, actuated by the cams 6 driven bv the wheels c, d, c, from the picking shaft/; g, g shuttle boxes at each end of the eoing part ; /», h arrangement of levers to conduct ec^ually each end of the geers i. I This loom has also, in addition to the ordinary stopping arrangement connected with the shuttle, one also for relaxing the reed in case the shuttle should be arrested in its course across the warp, whereby the danger, ordinarily incurred by that accident, of breaking many threads in the warp, is avoided ; it will also be seen that the bands called picking barids are supereeded by the ends of the picking levers striking the shuttJe direct ; thus, by these improvements, drUls are currently woven m this loom at the rate of 12o'to 130 picks per minute. Imports of flax and tow, or codilla of hemp and flax - - Linen yarn exported - ^ ,,.",. ". Linen manufactures exported (including linen - yarn, 881,312/. and 935,939/.) declared value - Vol. L fi ^ cwts. lbs. 1850 1,822,918 18,220,688 1851 1,194,184 18,518,273 £ 4,839,779 5,053,792 II i I At i i ! c I 794 FLINT. FLINT. (Pierre ci fusil, Fr. ; Fmcrstein, Germ.) The fracture of this fossil « nerfecilv conchoidal, sometimes glossy, and sometimes dull on the surface. It ,s y^vy Sard but breaks eadly, and affords very sharp-edged splintery fragments; whence it is a s^one which strikes most copious sparks with steel. It is feebly translucid has so fine LThlogeneous a texture as to beAr polishing, but possesses little lustre Its colours are very Various, but never vivid. The blackish-brown flint is that usually found m tie whL chalk It is nearly black and opaque, loses its colour in the fire, and becomes cmTsrwhUe and perfectly' opaque. Flints occur almost always in nodules or tuber- fulL concretions of^varioui and very irregular forms. These nodules, distributed in strata aronrthe chalk, alongside of one another and almost in contact, form extensive beds inTerrupted indeed, by a multitude of void spaces, so as to present, if freed from the eaHhrma^^^^^^^^^ i" whi^h'they are imbedded, a speciesof network with meshes, very irrpo-nlarboth in form and dimension. , , S nodule of sUex, especially those found in the chalk, are not always homogeneouB and solid Sometmes there is Remarked an organic form towards their centre, as a madr^po^e orTsS which seems to have served as their nucleus ; occasionally the Sntre^is hollow and ts sides are studded over with crystals of quartz, carbonate of iron, pyritetrncre^^^ silex or calcedony, filled with pulverulent silica nearly pure, or silex mixed with sulphur ; a very singular circumstance. Flints are observed to be generally humid when broken imrnediately after being dug out of the ground; a proplrty which disappears after a short exposure to the air. When dried^tney beconre more'brittle and more splintery, and sometimes their surfaces eat covered at old fractures with a thin film or crust of opaque silex. ^Flints calcined and ground to a powder enter into the composition of all sorts of fine ^'^Th^nrxU^iportant application of this siliceous substance i« ^^ th«/ormation of gun. flints for which purpose'^it must be cut in a peculiar manner The following characters d stineuLh good iiint nodules from such as are less fit for being manufactured. The best Te somewhat convex, approaching to globular; those which are very irregular, knobbld branlhed and tuberose, are generally full of imperfection. Good nodules Sm weigh more than 20 pounds ; when less than 2, they are not worth the working ^eHhou d have a greasy lustre, and be particularly smooth and fine grained. The SoL X vary from honey-yellow to blackish-brown, but it should be uniform ?hrouZut tSmp. and the translucency should be so great as to render letters legible through a sli^^^^^ one-fiftieth of an inch thick, laid down upon the paper. The FLINT. 795 fracture should be perfectly smooth, uniform, and slightly conchoidal ; the last property being essential to the cutting out of perfect gun flints. Four tools are employed by the gun-flint makers. First, a hammer or mace of iron with a square head, from 1 to 2 pounds weight, with a handle 7 or 8 inches long. The tool is not made of steel, because so hard a metal would render the strokes too harsh, or dry, as the workmen say. and would shatter the nodules irregularly, instead of cutting them with a clean conchoidal fracture. Second, a hammer with 2 points, made of good steel well hardened, and weighing from 10 to 16 ounces, with a handle 7 inches long passing through it in such a way that the points of the hammer are nearer the hand of the workman than the centre of gravity of the mass. Third, the disc hammer or roller, a small solid wheel or flat segment of a cylinder, parallel to its base, only two inches and a third in diameter, and not more than 12 ounces in weight. It is formed of steel not hardened, and is fixed upon a handle 6 inches long, which passes through a square hole in its centre. Fourth, a chisel tapering and bevelled at both extremities, 7 or 8 inches long, and 2 inches broad, made of steel not hardened ; this is set on a block of wood, which serves also for a bench to the workmen. To these 4 tools a file must be added, for the pur- pose of restoring the edge of the chisel from time to time. After selecting a good mass of flint, the workman executes the four following oper- ations on it 1. He breaks the block. Being seated upon the ground, he places the nodule of flint on his left thigh, and applies slight strokes with the square hammer to divide it into smaller pieces of about a pound and a half each, with broad surfaces and almost even fractures. The blows should be moderate, lest the lump crack and split in the wrong direction. 2. He cleaves or chips the flint. The principal point is to split the flint well, or to chip off scales of the length, thickness, and shape adapted for the subsequent formation of gun-flints. Here the greatest dexterity and steadiness of manipulation are necessary ; but the fracture of the flint is not restricted to any particular direction, for it may be chipped in all parts with equal facility. The workman holds the lump of flint in his left hand, and strikes with the pointed hammer upon the edges of the great planes produced by the firet breaking, whereby the white coating of the flint is removed in small scales, and the interior body of the flint is laid bare ; after which he continues to detach similar scaly portions from the clean mass. These scaly portions are nearly an inch and a half broad, two inches and a half long, and about one-sixth of an inch thick in the middle. They are slightly convex below, and consequently leave in the part of the lump from which they were separated a space slightly concave, longitudinally bordered by two somewhat projecting straight lines or ridges. The ridges produced by the separation of the first scales must naturally constitute nearly the middle of the subsequent pieces ; and such scales alone as have their ridges thus placed in the middle are fit to be made into gun-flints. In this man- ner the workman continues to split or chip the mass of flint in various directions, until the defects usually found in the interior render it impossible to make the requisite frac- tures, or until the piece is too much reduced to sustain the smart blows by which the flint is divided. 3. He fasldous the gun-flints. Five different parts maybe distinguished in a gun- flint. 1. The sloping facet or bevel part, which is impelled against the hammer of the lock. Its thickness should be from two to three twelfths of an inch ; for if it were thicker it would be too liable to break ; and if more obtuse, the scintillations would be less vivid. 2. The sides, or lateral edges, which are always somewhat irregular. 3. The back or thick part opposite the tapering edge. 4. The under surface, which is smooth and rather concave. And 5. The upper face, which has a small square plane between the tapering edge and the back, for entering into the upper claw of the cock. In order to fashion the flint, those scales are selected which have at least one of the above-mentioned longitudinal ridges ; the workman fixes on one of the two tapering borders to form the striking edge, after which the two sides of the stone that are to form the lateral edges, as well as the part that is to form the back, are successively' placed on the edge of the chisel in such a manner that the convex surface of the flint which rests on the forefinger of the left hand, is turned towards that tool. Then with the disc ham- mer he applies some slight strokes to the flint just opposite the edge of the chisel uuder- ueatli, and thereby breaks it exactly along the edge of the chisel. 4. Tlie finishing operation is the trimming^ or the process of giving the flint a smootli and equal edge ; this is done by turning up the stone and placing the edge of its tapering end upon the chisel, in which position it is completed by five or six slight strokes of the disc hammer. The whole operation of making a gun-flint, which I have used so many words to describe, is performed in less than one minute. A good workman is able to manufacture 1,000 good chips or scales* in a day (if the flint-balls be of good quality)^ 6X2 ■H "796 FLOUR OF WHEAT. FLY POWDER. V97 or 500 gun-flints. Hence, in the space of three days, he can easily cleave and finish '^T'::^:^n:i^^^^^^ for scarcely more than, half the scales are .o^L^and Sy ha?f the mass in the best flints is incapable of being ch.pped out ; so ?hrt\ seldom happens that the largest nodules furnish more than 60 g"";fl>nt8. ^ints form exceUent building materials ; because they give a firm hold to the mortar Wh.fr Sr^Srlv rough surfaces, and resist, by their nature, every vicissitude of tCther. ThTcou^ties of Kent, Essex, Suftblk, an'd Norfolk, contain many substantial '^'^OOrA^"^"'^^^^^ given by the Cornish miners to a vein of clay-stone, often ?rnrPvtouslv brushed over ..ith glue-size, and rubbed smooth with pumice stones. ^hrfrundftLr^ai^^^^^^^^^ ^.ith nnseed oil and ochre, or any cheap -lo"""^ "-"^;; i« fin tl^ok to be applied by the brush, and is therefore spread evenly by a long narrow their grain crossing one ^l^o|tier ^ f^^^^^^ Ire cut awav that correspond to the im- slices between. Applied in this ^»i' *« '*'3 ^'1'"^ of the block whiih takes up %t^7lZ ^'S;^tr. is the fluia glass floating iipon the iron produced '^^^^^^Jli:i!^^rtZ^i:f^^'^^'' -™e given to the FLObb-felLK y^«<>?f"^' v!I^.ffTn tho filature of the cocoons, which is carded like portions of ravelled silk broken ''%^'' ^^'^^^^^^^^ for making bands, shawli, Cotton or wool, and spun ^"to a soft coar^e > arn or tln-e^^^^^^^^ obtained, must be socks, and other common ^^^^ fabrics^ The flo^ steeped in water, and then subjected to P^ff^^^^^^' "'j^'^^^^'^,^^ After being dned it is Which rendci-s it too harsh anct short [^^ .tj^^.f ^i"^\^f J^h "he hands. It is now ready made still more pliant by j:«r^^^g.\^^"^.^,"l^CoN Manufa^^^^^^^ It is spun upo^ ■to be submitted to the carding engine, (teee Cotton j>ianli.aoiu ; r the flax wheel. ^„^^„ii^rwpnr clothes of homespun floss silk. Of The female peasants of Lombardy generally wear ""^^y'f.^^^^ j^^^^ been pro- late years, by \mproyed processes. Pretty fne fabrics of this ^^^^^J^J /^J^^^^f? h^ duced, both in England and France. M. ^4^^,' ^f^i^>^"'' JJ ,^^^ of scarfs and French national exhibitions of the objects of industry, a f ^J^^J f/jf > ^Sare shawls, on<^rre d. soie, closely ---^^-^^^ ^^^^^^^ or cerealia. See FLOUR ; the finely ground meal ot wheat, and oi any omer i.uiii!> ^'^^St'b r>v WTIKAT AdulUration, of, to detect.— ^e first method is by specific JlS^\?loTJ^Z^iiMTi^^ ia frequently done in F™"-. --^^^ |,Wcblontai,fs one pound of wheat flour will contain one poand and a hajf of the fec-J^ ^•'^Lrlllerrettd^rbytLTJ^^^^^ .ample will afl-ord, by the process prescribed under the article Bread. '^Z'^^^r^ir^^^^:^'^^^ .heat «o„. of . fine orange yellow, whereas it aftects the coloui' neither of fecula nor starch. 2nd. Pure muriatic acid colours good wheat flour of a deep violet, but dissolves fecula or starch, and forms with it a light, colourless, viscous fluid, decomposable b;r alkalis. It may also be observed, that as fecula absorbs less water than flour, this affords a ready means of detection. . . .,• * The adulteration with bean or pea flour may be detected by pouring boiling water upon it, which developes the pecuhar smell of these two substances. FLUWEPwS {Fleurs, Ft.; Blwnen, Germ.) of benzoin, of sulphur, of zinc, arts of white soft soap and old palm oil is to be dissolved in boiling water, using half a pound of soap to one gallon of water. Into this saponaceous solution, the paper impregnated with the said pulp is to be dipped, and then sized. They also prevent a transfer being taken with paper, by washing it with solution of sulphate of copper, drying it, and dipping it in phosphate of soda strong enough to convert the sulphate into a phosphate. FORMIATES ; are compounds of formic acid, with the salifiable bases. Many of them are susceptible of crystallization. FORMIC ACID ; {Acide Formique, Fr. ; Ameimnsaure, Germ.) exists in the bodies of wood ants, associated with the malic or acid of apples. The artificial formation of this animal secretion, is one of the most remarkable triumphs of modern chemistry. If 10 parts of tartaric acid, 14 of black oxide of manganese, 15 of concentrated sul- phuric acid, and from 20 to 30 of water be mixed and distilled in a retort, formic acid will be the liquid product; while carbonic acid will be disengaged. It may also be generated from other mixtures. This acid is transparent and colourless, of a pungent sour smell, a strongly acid taste, of specific gravity 1-1168 at 60° F., and may be rc-distiiled without suffering any change. It contains in its most concentrated form 1 9f per cent of water. The dry acid, as it exists in the formiat€&, is composed of 32-54 carbon, 2*68 hydrogen, and 64-78 oxygen: or of two volumes carbonic oxide gas, and one volume of vapour of water. It reduces the oxides of mercury and silver to the metallic state. It has not hitherto been applied to any use in the arts. FORMULA CHEMICAL, are symbols representing the different substances, simple and compound. FORMUL-E, CHEMICAL. 801 Name. Formula. Oxygen =100 Hydrogen =1. | Oxygen' 100-000 16 026 Hydrogen . . • H 6-2398 1-000 «H 12-4796 2-000 Nilrogea , • . N 88-518 14186 VOX 177086 28-372 Phosphorus . • • p 196-155 31-436 «p 392-310 68-872 Chlorine CI 221-325 35-470 2C1 442-650 70-940 Iodine . • • • I 768-781 123-206 21 1537-562 246-412 Carbon • • . C 76-437 12-250 2C 152-875 24-500 Boroa • • • B 135-983 21-793 2B 271-966 43-586 Silicon . • • • 8i 277-478 44-469 Selenium • • • Se 494-582 79 263 Arsenic • • • As 470-042 75-329 2As 940-084 150-659 Chromium ... Cr 351-819 56-383 2Cr 703-638 112-766 Molybdenum • • Mo 598-525 95-920 Tungstenium • TuorW 1183-200 189-621 Antimony • • . Sb 806-452 129-243 2Sb 1612-904 258-486 Tellurium Te 806-452 129-243 Tantalum • Ta 1153-715 184-896 2Ta 2307-430 369 792 Titaniam , , , Ti 389-092 62-356 Gold (aurum) . , . Au 1243013 199-207 2Au 2486-026 398-415 Platina Pt 1215220 194-753 Rhodium R 750-680 120-305 2R 1501-360 240610 Palladium . . Pd 714-618 114-526 Silver (argentum) Ag 1351-607 216-611 Mercury (hydrargyrus) . Hg 1265-822 202-863 2Hg 2531-645 405 725 Copper (cuprum) . • Ca 395-695 63415 2Cu 791-390 126-829 Uranium . • . U 2711-360 434-527 x%* *.t_ VXS 5422-720 869-154 Bismuth . • Bi 1330-376 213-208 2Bi 2660-752 426-416 Tin (stannum) • . Sa 735-294 117-839 Lead (plumbum) . . Pb 1294-498 207-458 • 2Pb 2588-996 414-917 Cadmium • • • F7 * Cd 696-767 111-665 Zinc .... Za 403-2-26 64-621 Nickel , Ni 369-675 59-245 Cobalt Co 368-991 59-135 2Co 737-982 118-270 Iron (fcrrum) , • , Fe 339-213 54-363 ^ ^ 2Fe 678-426 108-725 Manganese • • . Mn 355-787 57-019 Cerium , , 2Mii 711-575 114-038 Ce 574-718 92-105 2Ce 1149-436 184-210 Zirconiam Zr 420-238 67-348 vr^d • 2Zr 840-476 134-696 yttrium . , Y 401-840 64-395 Beryllium (glucinnm) Be 331-479 53-123 2Be 662-958 106-247 802 formulje, chemical. FORMULiG, CHEMICAL. 80S I Name. Formula. | ()x>geii= 100. IIydropeii= 1. Aluminum Magnesium Calcium Strontium Baiyt'im Lithium Natrium (sodium) Kalium (potassium) . Ammonia Cyanogen Al 2A1 Mg Ca Sr Ba T. Na 2\a K •2.N 210 2\C 171-167 342-234 158-353 256-019 547 285 856-88 J 27-757 290-897 581-794 489-916 214-474 329 911 27-431 54-863 25-378 41-030 87-709 137-325 20 474 46-620 93-239 78-515 34-372 52-872 S:-lphurete(l hydrogen . 2HS 213-644 34-239 Hydrochloric acid 2HC1 455-129 72-940 Hydrocyanic acid 2HNC 342-390 54-872 Water 211 112-479 18-026 Protoxyde of nitrogen . 2N 277-036 44-398 Deutoxyde of nitrogen N 188-518 30-212 Nitrous acid . 2N 477-036 76-449 Nitric acid . . 2N 677-036 108-503 Hyposulphurous acid . • S 301-165 48-265 Sulphurous acid . • •• s 401-165 64-291 Hypo«ulphuric acid • • 2S 902-330 144-609 Sulphuric acid . • ••• s 501-165 80-317 Phosphoric acid 2P 892-310 143-003 Chloric acid . . • 2C1 942-650 151-071 Perchloric acid . • 2C1 1042-650 167-097 Iodic acid . . • 21 2037-562 326-543 Carbonic acid . • • •• C 276-437 44-302 Oxalic acid . . • ••• 2C 452-875 72-578 Boracic acid . . . 2B 871-966 139-743 Silicic acid . . • Si 577-478 92-548 Selenic acid . •• Se 694-582 111-315 Arsenic acid . • ■ • 2As 1440-084 230-790 Protoxyde of chrome . • •• 2Cr 1003-638 160-840 Chromic acid . Cr 651-819 104-462 Molybdic acid . . Mo 898-525 143-999 Tunslic, or wolfram acid W 1483-200 237-700 Oxyde of antimony ••• 2Sb 1912-904 306-565 Antimonious acid • • Sb 1006-452 161-296 2Sb 2012-904 322-591 Antimonic acid 2Sb 2112-904 338-617 Name. Oxyde of tellurium Tantaiic acid . Titanic acid . Protoxyde of gold Pcroxyde of gold Oxyde of platina Oxyde of rhodium Oxyde of palladium Oxyde of silver Protoxyde of mercury Peroxyde of mercury Protoxyde of copper Peroxyde of copper Protoxyde of uranium Peroxyde of uranium Oxyde of bismuth Protoxyde of tin Peroxyde of tin Oxyde of lead . Minium . Brown oxyde of lead Oxyde of cadmium Oxyde of zinc Oxyde of nickel Oxyde of cobalt Peroxyde of cobalt Protoxyde of iron Peroxyde of iron Protoxyde of manganese Oxyde of manganese Perox)'de of manganese Manganesic acid Protoxyde of cerium Oxyde of cerium Zirconia Yttria GIncina, or berryllia Formala. Te 2Ta Ti 2Au 2Au Pt 2R Pd M 2Hg Hg 2Cu Cu U 2U 2iBi Sn Sn Pb 2Pb Pb Cd Za Ni Co 2Co Fe 2F Mn 2Mn Mn 2*Mii Ce 2Ce 2Zr Y 2Be Oxygrea= 100 . Hydrogen=l 1006-452 161-296 2607-430 417-871 589-092 94-409 2586-026 414-441 2786-026 446-493 1415-220 226-086 1801-360 228-689 814-618 130-552 1451-607 232-637 2631-645 421-752 1365-822 218-889 801-390 142-856 495-695 79-441 2811-360 450-553 5722-720 917-132 2960-752 474-49 835-294 133-866 935-294 149-892 1394-498 223-484 2888-996 462-995 1494-498 239-511 796-767 127-691 503-226 80-649 469-675 75-271 468-991 75-161 1037-982 166-349 439-213 70-389 978-426 156-804 455-787 73-045 1011-575 162-117 555-787 89-071 1211-575 194-169 674-718 108-132 1449-436 232-289 1140-476 182-775 501-840 80-425 962-958 154-325 804 FOUNDING. . Name { Formalii. Oxygen=100. Hydrog«n=l., Alnroina • • • • •• 2A) 642-334 t 109-942 Magnesia • • • Mg 258-353 41-404 Lime . « • • Cft 356-019 57-056 Strontia • • • • Sr 647-285 103-735 Baryta • • • Ba 956-880 153-351 Lithia • • • • L 227-757 36-501 Natron, or soda • • Nft 390-897 62-646 Peroxyde of sodinin • • 2Na 881-794 141-318 Kali, or potassa • • • K 589-916 94-541 Peroxyde of potassium . ••• K 789-916 126-593 Sulphate of potassa . • ■ ••• KS 1091081 174-859 Protosulphate of iron • • FeS 940-378 150-706 Persulphate of iron . • 2FeS3 2481-906 397-754 Protochloride of iron . • Fe2Cl 781-863 125-303 Perchloride of iron . 2Fe 2Cls 2006-376 321-545 Protochloride of mercury • 2Hg 2C1 2974-295 476-666 Perchloride of mercury • Hg2Cl 1708-472 273-803 Ferrocyanide of iron . • Fe 2NC-f 2K 2NC 2308-778 370-008 Alum . • • . KS-1-2A1S3-I-24 2H 5936-406 951-378 Feldspar K Si-f 2A1 Si3 3542-162 567-673 FOUNDING of metals, chiefly of Iron. The operations of an iron foundry consist iu re-melting the pig-iron of the blast furnaces, and giving it an endless variety of forms, by casting it in moulds of different kinds, prepared in appropriate manners. Coke is the only kind of fuel emplcyzd to effect the fusion of the cast-iron. The essential parts of a well-mounted iron foundry are, 1. Magazines for pig-irons of d-fferent qualities, which are to be mixed in certain pro- portions, for producing castings cf peculiar qualities; as also for coal, coke, sands, clay, powdered charcoal, and cow-hair for giving tenacity to the loam mouldings. 2. One or more coke ovens. 3. A workshop for preparing the patterns and materials of the moulds. It should contain small edge millstones for grinding and mixing the loam, and another mill for grinding coa? ^nd charcoal. 4. A vast area, called properly the foundry, in which the moulds are made and filled with the melted metal. These moulds are in general very heavy, consisting of two parts at least, which must be separated, turned upside down several times, and replaced very exactly upon one another. The casting is generally effected by means of large ladles or pots, in which the melted iron is transported from the cupola, where it is fused. Hence, the foundry ought to be provided with cranes, having jibs moveable in every direction. 5. A stove in which such moulds may be readily introduced as require to be entirely deprived of humidity, and where a strong heat may be uniformly maintained. 6. Both blast and air furnaces, capable of melting speedily the quantity of cast-iron to be employed each day. 7. A blowing machine to urge the fusion in the -furnaces. Fig. 650 represents the general plan of a well-mounted foundry, o is a cupola furnace, of which the section and view will be afterwards given ; it is capable of containing 5 tons of cast-iron, d is a similar furnace, but of smaller dimensions, for bringing down If tons. «" is a furnace like the first, in reserve for great castings. FOUNDING. go5 •n^* nh *' ^' ? v«stToundry apartmerit, whose floor, to a yard in depth, is Termed of san * and^charcoal powder, which have already been used for castings, and are readrfor hraiC mg up into a substratum, or to be scooped out when depth is wanted for (he moulds. There are besides several cylindrical pits, from five to seven yards m depth, placed near the furnaces. They are lined with brick work, and are usually left fuL of moulding sand. They are emptied in order to receive large moulds, care being had that their top IS always below the orifice from which the melted metal is tapped. These moulds, and the ladles full of melted metal, are lifted and transported by the arm of one or more men, when their weight is moderate ; but if It be considerable, they are moved about by cranes whose vertical shafts are placed at c, d, e, m correspondence, so that they may upon occasion ^ J • . „ ^ transfer the load from one to another. Each crane K composed principally of an upright shaft, embraced at top by a collet, and tuS below upon a pivot ma step; next of a horizontal beam, stretched out from nearly hf top of ihe former, with an oblique stay running downwards, like that of a gaHows ^The JaTre tt we^M^^'rlf- * ^""'"*^!' ""7'"^^^' *° ^^'^^^ '^' '^'^^' »« suspended for E«m Vv ml ' r ^^^''f '''"■'■f^^ 'f "^^^ ^^ 8^^'^*^ backwards or forwards along the wiZ'rlaro7ttVoSl\rir ^^"^°" --^-ism, whose long handle desLds By these arrangements in the play of the three cranes, masses weighing five tons mav kterio"rTf ' t^. ?h ' '"^ ^n ^'^' ^'^ ^''^''''' ^'"''''^^ "P^» «»y P«i«^ whatever n the interior of the three circles traced upon Jig. 650 with the points c, d, e, as centres Ea^4':sh^an\'6 air"^ ^'^^' ^'^ "^^^^^^^ ^^^^^ «^ '^^ ^»^- -- -^ -^ turn. ^^is the drying stove, having its floor upon a level with that of the foundry. /^,f, IS a supplementary stove for small articles. Si Sy ffj are the coking ovens. A, is the blowing machine or fan. |ld'.heTa"c"oK,f """" '"« '■'"'' '"« '»"■"-'?« ^'"-^ t", are the boiler and the furnace of the engine k\ workshop for preparing the loam and other materials of moulding. /, is the apartment for the patterns. .J**^ r M r°"' ^'^^u' ^''' ^'^ P^'^^^^ ^'^^^^ "n^e'- sheds or in the open air round the mm^nt'dtt'hl'' ""^'''t-' «^«« V«'"'^»»'« forge, a carpenter's shop,'and an Tpanmlnt mounted with vices for ch.pp.ng and rough cleaning the castings by chisels and files .n^ ' Mr,i"""^Tr^? ^^ ^'.^"'"^ "P«" * ^"^'•^ s»^^*ce of abSut 80 yards in each side and wil be capable, by casting in the afternoon and evening of each day, piJtly in large lishm'ent of"loTnn/'r'' '^ TJ"^ ""' ^^"°^ '^^ '^ ««^ ^«"« ^' annum; wTth an esU^ lishment of 100 operatives, including some moulding boys. • O/nmkmg the moulds.- 1 E^ch mould ought to present the exact form of its object. 2. It should have such solidity that the melted metal may be poured into it and fill entirely without altering its shape in any point. ^ ' " 3. The air which occupies the vacant spaces in it, as well as the carbureted eases S'Tx^andC the he'I'tTnd ""''' ^ T'^ ^?/' ^^^ '' ^''^^ are\ut p^rL' I'^conLTd iney expand b> the heat, and may crack, even blow up the moulds, or at anv rate become dispersed through the metal, making it vesicular and unsound. ^ Ihere are three distinct methods of making the moulds — J . In green sand ; 2. In baked sand ; 3. In loam. limUs "oreSl'i ?o' ,i,'?'^^^"V'"^\"« ^°;Pl«yed to make every sort of mould exceeds the what isT™ tn«n',h '"'• r^ '^'" merely indicate for each species of moulding, Tuch mou?d^r",il« Ic^^"" '°",' ' -^"^ ' '^^" '^^" ^^'^''^^ the fabrication of a few M^Sr^yj most proper to give general views of this peculiar art. fromT^^frahv/hTl'^rh T:^^^ """"^ ?r"" ^'S^^^» t«« mixture of the sand as it comes «1 Tn iLh 1 ' ^"^^^"to"e twelfth its bulk of coal reduced to powder, and damp- t^P ohl.r. • "'^""^;;«^ t« ^«™^ PO^o»s compound, capable of prcsc/vin? the forms <5^ nni pvi. h'"'^''"'''^ T^" -'' . ^^'^ '^"^ °"g^t to be slightly argillaceous; with particks hPPn fi^r. " -..* pin's head in size When this mixture has once served for a mould, anl Ltenn -n"" f^f'^lv ''""'V^' '"^P^^^^^ ^^^''^ '^<^'P' ^^^ the coarsest castings; and IS generally used for filhng up the bottoms of fresh moulds. i-or moulding any piece in green sand, an exact pattern of the object must be pre- It lit 806 FOUNDING. 1 ' t 1 ■i = pared in wood or metal ; the latter being preferable, as not liable ^o warping, swelling, or shrinkage. A couple of iron frames form a case or box, which serves as an envelope to the mould. Such boxes constitute an essential and very expensive part of the furniture of a foundry. It is a rectangular frame, without bottom or lid, whose two largest sides are united by a series of cross bars, parallel to each other, and placed from 6 to 8 inches apart. The two halves of the box carry ears corresponding exactly with one another ; of which one set is pierced with holes, but the other has points which enter truly into these holes, and may be made fast in them by cross pins or wedges, so that the pair becomes one solid body. Within this frame there is abundance of room for containing the pattern of the piece to be moulded with its incasing sand, which being rammed into the frame, is retained by friction against the lateral faces and cross bars of the mould. When a mould is to be formed, a box of suitable dimensions is taken asunder, and each half, No. 1 and No. 2, is laid upon the floor of the foundry. Green sand is thrown with a shovel into No. 1, so as to fill it; when it is gently pressed in with a rammer. The object of this operation is to form a plain surface upon which to lay in the pattern with a slight degree of pressure, varying with its shape. No. 1 being covered with sand, the frame No. 2 is laid upon it, so as to form the box. No. 2 being now filled car^ fully with the green sand, the box is inverted, so as to place No. 1 uppermost, which is then detached and lifted off in a truly vertical position ; carrying with it the body of sand formed at the commencement of the operation. The pattern remains inribedded in the sand of No. 2, which has been exactly moulded upon a great portion of its surface. The moulder condenses the sand in the parts nearest to the pattern, by sprinkling a little water upon it, and trimming the ill-shaped parts with small iron trowels of different kinds. He then dusts a little well-dried finely-sifted sand over all the visible surface of the pattern, and of the sand surrounding it ; this is done to prevent adhesion when he replaces the frame No. 1. He next destroys the preparatory smooth bed or area formed in this frame, covers the pattern with green sand, replaces the frame 1 upon 2, to reproduce the box, and proceeds to fill and ram No. 1, as he had previously done No. 2. The object of this operation is to obtain very exactly a concavity in the frame No. 1, having the shape of the part of the model impressed coarsely upon the surface formed at the beginning, and which was meant merely to support the pattern and the sand sprinkled over it, till it got imbedded in No. 2. The two frames in their last position, along with their sand, may be compared to a box of which No. 1 is the lid, and whose interior is adjusted exactly upon the enclosed Pattern. . • ,v If we open this box, and after taking out the pattern, close its two halves again, then pour in melted metal till it fill every void space, and become solid, we shall obviously attain the wished-for end, and produce a piece of cast iron similar to the pattern. But many pi-ecautions must still be taken before we can hit this point. We must first lead through the mass of sand in the frame No. 1 one or more channels for the introduction of the la-slted metal ; and though one may suffice for this purpose, another must be made for letting the air escape. The metal is run in by several orifices at once, when the piece has considerable surface, but little thickness, so that it may reach the remotest points sufficiently hot and liquid. , . , The parts of the mould near the pattern must likewise be pierced with small holes, by means of wires traversing the whole body of the sand, in order to render the mould more porous, and to facilitate the escape of the air and the gases. Then, befor; liftmg off the frame No. 1, we must tap the pattern slightly, otherwise the sand enclosing it would stick to it in several points, and the operation would not succeed. These gentle jolts are given by means of one or more pieces of iron wire which have been screwed vertically into the pattern before finally ramming the sand into the frame No. 1, or which enter merely into holes in the pattern. These pieces are sufficiently long to pass out through the sand when the box is filled ; and it is upon their upper ends that the horizontal blows of the hammer are given ; their force being regulated by the weight and magni- tude of the pattern. These rods are then removed by drawing them straight out ; after which the frame No. 1 may he lifted off smoothly from the pa"tlern. The pattern itself is taken out, by lifting it in all its parts at once, by means of screw pins adjusted at the moment. This manoeuvre is executed, for large pieces, almost always by several men, who, while they lift the pattern with one hand, strike it with the other with small repeated blows to detach the sand entirely, in which it is generally more engaged than it was in that of the frame No. 1. But in spite of all these precautions, there are always some degradations in one or other of the two parts of the mould ; which are immediately repaired by the workman with damp sand, which he applies and presses gently with his trowel, so as to restore the injured forms. i • j v Hitherto I have supposed all the sand rammed into the box to be of one kmdj bat FOUNDING. 807 from economy, the green sand is used only to form the portion of the mould next the pattern, in a stratum of about an inch thick ; the rest of the surrounding space is filled with the sand of the floor which has been used in former castings. The interior layer round the pattern is called, in this case, new sand. It may happen that the pattern is too complex to be taken out without damaging the mould, by two frames alone ; then 3 or more are mutually adjusted to form the box. When the mould, taken asunder into two or more parts, has been properly repaired, its interior surface must be dusted over with wood charcoal reduced to a very fine powder, and tied up in a small linen bag, which is shaken by hand. The charcoal is thus sifted at the moment of application, and sticks to the whole surface, which has been previously damped a little. It is afterwards polished with a fine trowel. Sometimes, in order to avoid using too much charcoal, the surfaces are finally dusted over with sand, very finely pulverized, from a bag like the charcoal. The two frames are now replaced with great exactness, made fast together by the ears, with wedged bolts laid truly level, or at the requisite slope, and loaded with considerable weights. When the casting is large, the charcoal dusting, as well as that of fine sand, is suppressed. Everything is now ready for the introduction of the fused metal. • Moulding in baked or used sand. — ^The mechanical part of th:? process is the same as of the preceding. But when the castings are large, and especially if they are tall, the hydrostatic pressure of the melted metal upon the sides of the mould cannot be counter- acted by the force of cohesion which the sand acquires by ramming. We must in that case adapt to each of these frames a solid side, pierced with numerous small holes to give issue to the gases. This does not form one body with the rest of the frame, but is attached extemporaneously to it by bars and wedged bolts. In general, no ground coal is mixed with this sand. Whenever the mould is finished, it is transferred to the drying stove, where it may remain from 12 to 24 hours at most, till it be deprived of all its humidity. The sand is then said to be baked or annealed. The experienced moulder knows how to mix the different sands placed at his disposal, so that the mass of the mould as it comes out of the stove may preserve its form, and be sufficiently porous. Such moulds allow the gases to pass through them much more readily than those made of green sand ; and in general the castings they turn out are less vesicular, and smoother upon the surface. Sometimes in a large piece, the three kinds of moulding, that in green sand, in baked sand, and in loam, are combined to produce the best result. Moulding in loam. — This kind of work is executed from drawings of the pieces to be moulded, without being at the expense of making patterns. The mould is formed of a pasty mixture of clay, water, sand, and cow's-hair, or other cheap filamentous matter, kneaded together in what is called the loam mill. The proportions of the ingredients are varied to suit the nature of the casting. When the paste requires to be made very light, horse dung or chopped straw is added to it. I shall illustrate the mode of fabricating loam moulds, by a simple case, such as that of a sugar pan. Fig. 651 is the pan. There is laid upon the floor of the foundry an annular platform of cast-iron, a by fig. 652; and upon its centre c, rests the lower extrem- ity of a vertical shaft, adjusted so as to turn freely upon itself, while it makes a wooden pattern, e /, fig. 653, describe a surface of revolution identical with the internstl surface reversed of the boiler intended to be made. The outline, e g, of the pattern is fashioned so as to describe the surface of the^edge of the vessel. Upon the part a d b dyfig. 652, of th^ flat cast-iron ring, there must next be constructed, with bricks laid either flat or on their edge, and clay, a kind of dome, h i k, fig. 653, from two to four inches thick, 652 653 661 according to the size and weight of the piece to be moulded. The external surface of the bricif dome ought to be everywhere two inches distant, at least, from the surface de- scribed by the arc e /. Before building up the dome to the point t, coals are to be placed m its inside upon the floor, which may be afterwards kindled for drying the mould. The top is then formed, leaving at t, round the upright shaft of revolution, only a very small outlet. This aperture, as also some others left under the edges of the iron ring, enable the moulder to light the fire when it becomes necessary, and to graduate it so as to make it last long enough without needing more fuel, till the mould be quite finished and dry. The combustion should be always extremely slow. Over the brick dome a pasty layer of loam is applied, and rounded with the mould 808 FOUNDING. FOUNDING. 809 lit I I &i I I II g «/; this surface is then coated with a much smoother loam, by means of the concave edge of the same mould. Upon the latter surface, the inside of the sugar pan is cast; the line f g having traced, in its revolution, a ledge m. The fire is now kindled, and as the surface of the mould becomes dry, it is painted over by a brush, with a mixture of water, charcoal powder, and a little clay, in order to prevent adhesion between the sur- face already dried and the coats of clay about to be applied to it. The board g e / is now removed, and replaced by another, g' e' f. Jig. 654, whose edge «' f describes the outer surface of the pan. Over the surface e, /, a layer of loam is applied, which is turned and polished so as to produce the surface of revolution e' /', as was done for the surface ef; only in the latter case, the line e' g' of the board does not form a new shoulder, but rubs lightly against m. The layer of loam included between the two surfaces e /, t' fy is an exact representa- tion of the sugar pan. When this layer is well dried by the iieat of the interior fire, it must be painted like the former. The upright shaft is now removed, leaving the small vent hole through which it passed to promote the complete combustion of the coal. There must be now laid horizontally upon the ears of the platform d rf, jig. 652, an- other annular platform p q, like the former, but a little larger, and without any cross-bar. 654 The relative position of these two platforms is shown in fig. 656. Upon the surface e' /', fig. 655, a new layer of loam is laid, two inches thick, of which the surface is smoothed by hand. Then upon the platform p g, fig. 656, a brick vault is constructed, whose inner surface is applied to the layer of loam. This contracts a strong adherence ■with the bricks which absorb a part of its moisture, while the coat of pamt spread over the surface e' /', prevents it from slicking to the preceding layers of loam. The brick dome ought to be built solidly. The whole mass is now to be thoroughly dried by the continuance of the fire, the draught of which is supported by a small vent left in the upper part of the new dome ; and when all is properly dry, the two iron platforms are adjusted to each other by pin points, and p q is lifted off, taking care to keep it in a horizontal position. Upr n this platform are removed the last brick dome, and the layer of loam which had been applied next to it; the latter of which represents exactly by its inside the mould of the surface «'/', that is, of the outside of the pan. The crust contained between e f and e' f is broken away, an operation easily done without injury to the surface e /, which represents exactly the inner surface of the pan ; or only to the shoulder w, corresponding to the edge of the "vessel. The top aperture through which the upright shaft passed must be now closed ; only the one is kept open in the portion of the mould lifted off upon p q ; because through this opening the melted metal is to be poured in the process of casting. The two plat- forms being replaced above each other very exactly, l^y means of the adjusting pin points, the mould is completely formed, and ready for the reception of the metal. When the object to be moulded presents more complicated forms than the one now chosen for the sake of illustration, it is always by analogous processes that the workman construct' his loam moulds, but his sagacity must hit upon modes of executing many things which at first sight appear to be scarcely possible. Thus, when the forms of the interior and exterior do not permit the mould to be separated in two pieces, it is divided into several, which are nicely fitted with adjusting pins. More than two cast-iron rings or platforms are sometimes necessary. When ovals or angular surfaces must be traced instead of those of revolution, no upright shaft is used, but wooden or cast-iron guides made on purpose, along which the pattern cut-out board is slid according to the drawing of the piece. Iron wires and claws are often interspersed through the brick work to give it cohesion. The core, kernel, or inner mould of a hollow casting is fre- quently fitted in when the outer shell is moulded. I shall illustrate this matter in the case of a gas-light retort, /g. 657. The core of the retort cnght to have the form e « « «, and be very solid, since it cannot be fixed in the outer mould, for the casting, except in the part standing out of the retort towards m m. It must be modelled in loam, upon a piece of cast-iron called a lanternj made expressly for this purpose. The lantern is a cylinder or a truncated hollow cone of cast-iron, about half an inch thick ; and differ- ently shaped for every different core. The surface is perforated with holes of about half an inch in diameter. It is mounted by meaiiis of iron cross-bars, upon an Iron axil, which traverses it in the direction of its length. Fig. 658 represents a horizontal section through the axis of the core; g h is the axis of the lantern, figured itself »i i h 657 668 659 fc t ; o 1 1 is a kind of disc or dish, perpendicular to the axis, open at 1 1, forming one piece with the lantern, whose circumference o o presents a curve similar to the section of the core, made at right angles to its axis. We shall see presently the two uses for which this dish is intended. The axis g A is laid upon two gudgeons, and handles are placed at each of its extremities, to facilitate the operation in making the core. Upon the whole surface of the lantern, from the point h to the collet formed by the dish, a hay cord as thick as the finger is wound. Even two or more coils may be applied, as occa- sion requires, over which loam is spread to the exact form of the core, by applying with the hand a board, against the dish o o, with its edge cut out to the desired shape ; as also against another dish, adjusted at the time towards A; while by means of the handles a rotatory movement is given to the wh» a « S o u to — 5« to—12P to— 18» to — 25* Snow - - - 3 parts Diluted sulphuric acid - 2 From -f 32» to — 23* 55 Snow Muriatic acid - 8 parts - 6 From -f 32« to — 27» 59 Snow Dilu ted nitric acid Snow Muriate of lime - 7 parts - 4 From -f 32? to — 30° 62 - 4 parts - 5 From -I- 32° to — iOP 72 Snow - - Cryst. muriate of lime 2 parts I p^^^ -I- 32° to — 50° 82 Snow L_Potash^ 3 parts 4 From 4- 32? to — 51° 83 FREEZING. 815 N. B. — The reason for the omissions in the last column of the preceding table is, the thermometer sinking in these mixtures to the degree mentioned in the preceding coliuniu and never lower, whatever may be the temperature of the materials at mixing. II. — Table, consisting of Frigorific Mixtures, having the power of generating or cre- ating cold, without the aid of ice, sufficient for all useful and philosophical purposes, in any part of the world at any season. Frigorific Mixtures without Ice. MIXTURES. Thermometer sinks. Degree of cold produced. Muriate of ammonia - - 5 parts Nitrate of potash - - 5 Water - - - 16 From -j- 50° to -{- 10° 40» Muriate of ammonia - 5 parts Nitrate of potash - - 5 Sulphate of soda - - 8 Water - - - 16 From -j- 50° to -f- 4° 46 Nitrate of ammonia - - 1 part Water - - - 1 From + 50° to -|- 4° 46 Nitrate of ammonia - - 1 part Carbonate of soda - - 1 Water - - - 1 From -f 50° to — 7° 57 i ^1 Sulphate of soda - - 3 parts Diluted nitric acid - - 2 From -{- 50° to — 3° 53* ; Sulphate of soda - - 6 parts Muriate of ammonia - 4 Nitrate of potash - - 2 Diluted nitric acid - - 4 From -f 50° to — 10° 1 60 Sulphate of soda - - 6 parts Nitrate of ammonia • - 5 Diluted nitric acid - - 4 From -f 50° to — 14° 64 Phosphate of soda - - 9 parts Diluted nitric acid - - 4 From -j- 50° to — 12° 62 Phosphate of soda - - 9 parts Nitrate of ammonia - - 6 Diluted nitric acid - - 4 From + 50° to — 21° 71 Sulphate of soda - - 8 parts Muriatic acid - - - 6 From 4- 60° to 0° 50 Sulphate of soda - - 5 parts Diluted sulphuric acid - 4 From 4- 50 to -f 3° 47 N. B. — If the materials are mixed at a warmer temperature than that expressed in the table, the eflfect will be proportionably greater ; thus, if the most powerful of these mixtures be made when the air is -|- 85°, it will sink the thermometer to -j- 2°. HI. — ^Table consisting of Frigorific Mixtures selected from the foregoing Tables, and combined so as to increase or extend cold to the extremest degrees. Combinations of Frigorific Mixtures. MIXTURES. Thermometer sinks. DegTe» of eM produced. Phosphate of soda - - 5 parts Nitrate of ammonia - - 3 Diluted nitric acid - - 4 From 0° to — 34° S4» Phosphate of soda - - 3 parts Nitrate of ammonia - - 2 Diluted mixed acids - - 4 From — 34° to — 60° 16 Snow - - • 3 parts Diluted nitric acid - - 2 From 0° to — 46° 46 816 II FUEL. TABLE m.—coniinued. FUEL. 817 IdiXTURES. Thermometer •inks. Beg. of cold produced. Snow ... Dilated sulphuric acid Diluted nitric acid • 8 parts . 3 - 3 From — l(y* to — 66" 46 Snow - - - - Diluted sulphuric acid - - 1 part - 1 From — 20® to — 60* 40 Snow - - - - Muriate of lime - • 3 parts - 4 From -\- 2(P to — 48® 68 Snow - - - - Muriate of lime - - 3 parts - 4 From 4- 10° to — 54° 64 Snow - . - - 1 Muriate of lime - - 2 parts - 3 From — 15° to — 68° 53 Snow - - - - Cryst. muriate of lime - - 1 part - 2 From 0° to — 66° 66 Snow - - - - Cryst. muriate of lime - - 1 part - 3 From — 40° to 73° 33 Snow - - - - Diluted sulphuric acid - - 8 parts - 10 From — 68° to — 91° 23 ^- B'— The materials in the first column are to be cooled, previously to mixing, to the temperature required, by mixtures taken from either of the preceding tables. Water absorbs 1000 degrees of heat in becoming vapor; whence, if placed in a saucer within an exhausted receiver, over a basin containing strong sulphuric acid, it will freeze by the rapid absorption of its heat into the vapor so copiously formed under these circum- stances. But the most powerful means of artificial refrigeration is afforded by the evaporation of liquefied carbonic acid gas; for the frozen carbonic acid thus obtained has probably a temperature 100° under zero; so that when a piece of it is laid upon quicksilver, it in- stantly congeals this metal. The more copious discussion of this subject belongs to chemical science. FRENCH BERRIES; Berries of Avignon. FRICTION, counteraction of; see Lubrication, FRIT ; see Enamel and Glass. FUEL (Combustible, Fr. ; Brennstoff, Germ.) Such combustibles as are used for fires or furnaces are called fuel, as wood, turf, pit- coal. These differ in their nature and in their power of giving heat. I. Wood, which is divided into hard and soft. To the former belong the oak, the beech, the alder, the birch, and the elm ; to the latter, the fir, the pine of different sorts, the larch, the linden, the willow, and the poplar. Under like dryness and weight different woods are found to afford equal desrees of heat in combustion. Moisture diminishes the heating power in three ways ; by diminish- ing the relative weight of the ligneous matter, by wasting heat in its evaporation, and by causing slow and imperfect combustion. If a piece of wood contain, for example, 25 per cent, of water, then it contains only 75 per cent, of fuel, and the evaporation of that water will require ^ part of the weight of the wood. Hence the damp wood is of less value in combustion by ^ or 2 than the dry. The quantity of moisture in newly felled wood amounts to from 20 to 50 per cent. ; birch contains 30, oak 35, beech and pine 39, t^r' ^^' -^^^°^^'^^? to their different natures, woods which have been felled and cleft for 12 months contain still from 20 to 25 per cent, of water. There is never less than 10 per cent, present, even when it has been kept long in a dry place, and though it be dried in a strong heat, it will afterwards absorb 10 or 12 per cent, of water. If it be too strongly kiln dried, its heating powers are impaired by the commencement of carbon- ization, as if some of its hydrogen were destroyed. It may be assumed as a mean of many experimental results, that 1 pound of artificially dried wood will heat 35 pounds of water from the freezing to the boiling point; and that a pound of such wood as con- tains from 20 to 25 per cent, of water will heat 26 pounds of ice-cold water to the same degree. It is better to buy wood by measure than by weight, as the bulk is very little mcreased by moisture. The value of different woods for fuel is inversely as their mois- ture, and this may easily be ascertained by taking their shavings, drying them in a heat of 140° F., and seeing how much weight they lose. From every combustible the heat is diffused either by radiation or by direct commnni- eation to bodies in contact with the flame. In a wood fire the quantity of radiating heat IS to that diffused by the air as 1 to 3 ; or it is one fourth of the whole heating power k3 ^^''''°''^- ^^« different charcoals afford, under equal weights, equal quantities ot hH in.Tl ""y/^*^^^°"' "P^l^ an average, that a pound of dry charcoal is capabkof henting 73 pounds of water from the freezing to the boiling point; but when it has been dalllTJ'""' 'T'^ J? '^' ^'l' ^^^"'^^."•"^ ^* ^«^«» 10 P^r <^ent. of water, whichl p^- Ually decomposed in the combustion into carbureted hydrogen, which causes flwne. whereas pure dry charcoal emits none. ^ s * *^" vouaca uoiuc, an^from'h?rS'wL:^^?9'?^\?°°' '""a ^^. ^^'^^s, Upon an average, from 8 to 9 pounds, « WhTo. • iV^ '"^ ^^ P°""if ' *"^ ^^"^^ ^^^ ^^"er are best adapted to m^ntain rhivlof'thr^hTemitrer"* ^'^ "'^^^^'^^ ^^^' ^'-^ ^^--^ fires' constitutes one rimfi'n,f,nt v^' Jl^ ?"^*i^ • ""^ ^^t ''^^'^ *'^ «'"^°st indefinite, and give out very va- nous quantities of heat m their combustion. The carbon is the heat-giving constituent, and It amounts, in different coals, to from 75 to 95 per cent. One pou^d of go«i dS will upon an average, heat 60 pounds of water from the freez"ngTthe LlungC^^t Small coal gives out three fourths of the heat of the lar-er lumos The raSi«?^/hp«i emitted by burning pitcoal is greater than that by charcoa? ^ ^ ^^^ tn fiQ n ^fpii/oal.-The heating power of good coke is to that of pitcoal as 75 to 69. One pound of the former will heat 65 pounds of water from 32° to 212^ so that Its power ,s equal to nine tenths of that of wood charcoal ' V. Turf or peat.— One pound of this fuel will heat from 25 to 30 pounds of water erh/;rrticL'\^d il^'rkd'r '''"' '^-^^^^l "P°" ^^^ compactness anrf"eiom fJ^m «.wi^^ following table the fourth column contains the weight of atmospherical air substance.'^'" "" '"'^"'''^ ^"' '^' '""^^^^^ combustion of a ^und of each paSculS Species of Rombastible. Perfectly dry wood Wood in its ordinary state Wood charcoal - Pitcoal - - . Coke - . . Turf Turf charcoal Carbureted hydrogen gas - Oil Wax Tallow Alcohol of the shops Pounds of water >vhich a pound can heat from 0° to 212°. leu 35 00 26-00 73-00 6000 65-00 30-00 64-00 76-00 78-00 52-60 Pounds of boiling water evaporated by 1 pound. 6-36 4-72 13-27 10-90 11-81 5-45 11-63 13-81 14-18 9-56 Weight of atmospheric air at 32°, to bam 1 pound. 5-96 4-47 11-46 9-26 11-46 4-60 9-86 14-58 1500 11-60 The quantity of air stated in the fourth column is the smallest possible reonired in iTh n^r"'^"'''^'"' ""^ ^^ ^^^"^'y ^^^« than would be necessary^!n p acS wte e much of the air never comes into contact with the burning body and where h ^n!^ quently never has its whole oxygen consumed. The heating powe'r seated rthe seco-S Tne draught of air usually carries off at least 1 of the heat and mnrp if iiJ\^ ture be very high when it leaves the vessel. ^In this^ e It ^lyTmoim to o^^^ of the whole heat or more,- without reckoning the loss by radiaiiorand cond"rction which, however, may be rendered very small by enclosing the fire and flues within nr^' per non-conducting and non-radiating materials ^ It appears that, in practice, the quantity of heat which may be obtained from anv com £e" S' VS:'JlCT\^''r'''' "^r ^^^^ -^^^ lhVnaJ^:re "f theTl^^^^^ heated. In heating chambers by stoves, and water boilers by furnace^; the effluent heat i"uan?itv rcL'nt'l ''"r ^/k"'? V^^ ^ ""^^^ ^^''^ ^-y be reduced to a ver^ molrafe herth^'ln hPr^hrJ,rh /^^'^^/^ ^'^^^'^ ^^^^^ ^^^ ^^^^ constructed re/erberatory to concert 7^nLlV.nrw^^ °^'*^*'". ^"^•""^'' ^"^ P^""'^ "^ <^°«^ '« '^^^^^''^ «^^ ^ith the best built boiler, 9 pounds «1 water; the deficiency from the maximum effect being here If, or nearly one skth. In many cases, the hot air which passes into the flues or chimneys may be bene- Ill 11 818 FULLER'S EARTH. ficially applied to the heating, drying, or roasting of objects ; but care ought to be takeu that the draught of the fire be not thereby impaired, and an imperfect combustion of th« fuel produced. For at a low smothering temperature both carbonic oxyde and carburet* ed hydrogen may be generated from coal, without the production of much heat in the fire-place. To determine exactly the quantity of heat disengaged by any combustible in the act of burning, three different systems of apparatus have been employed : 1. the calorimeter of Lavoisier and Laplace, in which the substance is burned in the centre of a vessel, whose walls are lined with ice ; and the amount of ice melted, measures the heat evolved ; 2. the calorimeter of Watt and Rumford, in which the degree of heat communicated to a given body of water affords the measure of temperature ; and 3. by the quantity of water evap- orated by different kinds of fuel in similar circumstances. If our object be to ascertain the relative heating powers of different kinds of fuel, we need not care so much about the total wasle of heat in the experiments, provided it be the same in all ; and therefore they should be burned in the same furnace, and in the nme way. But the more economically the heat is applied, \Le greater certainty will there be in the results. The apparatus ^g. 480, is simple and well adapted to make such com- parative trials of fuel. The little furnace is covered at top, and transmits its burned a'r by c, through a spiral tube immersed in a cistern of water, having a thermometer inserted near its top, and another near its bottom, into little side orifices a a, while the efiluent air escapes from the upright end of the tube b. Here also a ther- mometer bulb may be placed. The average in- dication of the two thermometers gives the mean temperature of the water. As the water evapo- rates from the cistern, it is supplied from a vessel placed alongside of it. The experiment should be begun when the furnace has acquired an equa- bility of temperature. A throttle valve at c serves to regulate the draught, and to equalize it in the different experiments by means of the temperature of the effluent air. When the water has been heated the given number of degrees, which should be the same in the different experiments, the fire may be extinguished, the remaining fuel weighed, and compared with the original quantity. Care should be taken to make the combustion as vivid and free from smoke as possible. On the measurement of heat, and the qualities of different kinds of coal, I made an elaborate series of experiments, a few vears aso, of which the following is an outline. The first and most celebrated, though probably not the most accurate apparatus for measuring the quantity of heat transferable from a hotter to a colder body, was the calorimeter of Lavoisier and Laplace. It consisted of three concentric cylinders of tin plate, placed at certain distances asunder ; the two outer interstitial spaces being filled with ice, while the innermost cylinder received the hot body, the subject of experiment. The quantity of water discharged from the middle space by the melting of the ice in it, served to measure the quantity of heat given out by the body in the central cylinder. A simpler and better instrument on this principle would be a hollow cylinder of ice of proper thickness, into whose interior the hot body would be introduced, and which would indicate by the quantity of water found melted within it the quantity of heat absorbed by the ice. In this case, the errors occasioned by the retention of water among the fragments of ice packed into the cylindric cell of the tin calorimeter, would be avoided. One pound of water at 172** F., introduced into the hollow cylinder above described, will melt exactly one pound of ice j and one pound of oil heated to 172° will melt half a pound. The method of refrigeration, contrived at first by Meyer, has been in modem times brought to great perfection by Dulong and Petit. It rests on the principle, that two surfaces of like size, and of equal radiating force, lose in like times the same quantity of heat when they are at the same temperature. Suppose for example, that a vessel of polished silver, of small size, and very thin in the metal, is successively filled with dif- ferent pulverized substances, and that it is allowed to cool from the same elevation of temperature ; the quantities of heat lost in the first instant of cooling will be always equal to each other; aud if for one of the substances, the velocity of cooling is double of that for another, we may conclude that its capacity for heat is one half, when its weight is the same ; since by losing the same quantity of heat, it sinks in temperature double the number of degrees. The method of viixtures, — In this method, two bodies are always employed ; a hot body which becomes cool, and a cold body, which becomes hot, in such manner that all FUEL. 819 the caloric which goes out of the former is ( xpended in heating the latter. Suppose tor example, that we pour a pound of quicksilver at 212° F., into a pound of wateVlt nilrl ^l"'*^'^^»Iver will cool and the water will heat, till the mixture by stirring ac VZu u ^''"^'"O" temperature. If this temperature was 122°, the wa»er and mercury mn.i nftiT! T^' capacities, since the same quantity of heat would produce in an equiU t^e wa Pr rnV^H ^^^^^^^^^^/^S^ changes of temperature, viz., an elevation of 9^^ o hive a MnPrT"'''? ''?^,\"o'^? '^^''^^'y- B'^t in realit;, the mixture is found watPr .. ;„ t^^7^5?,t"^« o^ «"ly 37r, showing that while the mercury loses 174^° the tTat the « r//v "> ' '""" '"'"'^^T V" [^' ^"'^« «^^^«"^ 32 to 1 ; whence it is concluded, hat the c* ac.ty of mercury ,s J- of that of water. Corrections must be made for Si ThTfnir. ' vessel and for the heat dissipated during the time of the experiment. ford LrwZ^'l.Lr-^'' •"""'''' ^^""^"'^ ^P^" '^' •''^"^^ l>"'^^ipl^ ^« that of Count Rum- for measu^^^ ZTlll?'^'"'''"TT' "'''^' ^^ «^o«^idered as an equally correct instrument bn sTn?P if'..n i\ • ^"^u"*^ ^^'^ preceding, but one of much more general applica- the latent hit nff'""''""/''", ^"''"'^^^ ^^ ^"^^ disengaged in combustion, as well um ine latent heat of steam and other vapors. , « «• ^•"1^-^ I III - (Scale about } inch to the foot.) wirlrrfraVe^ rZ^A'dit^.l^^^^^^^ ^' f^^% '00 gallons of a zig-zag horizontal flue, or flat p?pe rfc ^n^ in.h.c T^ ?* '°/°"' different levels, by in a round pipe at c, whU^hvltlth^^^^ ?"1°''' deep, ending below receives there into it the top o?a Lall bSj Jd ^ur" a"ef ' tV.T" '"'' ^' ^^ ^""^ contains the fuel. It is surrounded at the distance of one in. h^ '""^"™°!.t <^r"cible which is enclosed at the same time hy the \u{lTnf*hl f ^ ^J "" '^^'^^'^ crucible, of stagnant air between the crucTbls's eJvinl to pLventTheTertV^^^'T' ' ^'-^ '"'^"^ .nto the atmosphere round the body of the furnace A ^^l .^r """^ ^^'?^ dissipated louble bellows, enters the ash-pit of the furnace at* ontsT t'S"""^ V'' °^ ^y^^^^^^' gentle blast, to carry on the combustion, kindkd at firsr W h«ir '"P^^'^' ^ ''"^^^ ^"^ charcoal. So completely is the heat wh ch?s dJ.PnL/i K^il^u^"" •^'^''^^ °^ '"ed-hot by the wacer in the bath, that tSe air dtchargeTrthe^^^^ orffio"'"'^.^ '"^' "^"^^^ «ame temperature as the atmosphere '^''"^'^^^^ ^^ ^*^« t<>P orifice g, has usually the the zig-zag tin plate flue, and a rim o7^;„„fht Ir™ 1^3r",rT''- J-"^""""* Since the specific heat of copper is to thaTrf water" s'm To ^nnn.T''"" f r""^; the vessel is equal to that of 8 pounds of water fnrws\,i'^' "■* ^'""""^ '"" "^ tion is made by leaving 8 pound' of water ou, of the^Mt? nn^^^^^ "/ exact eorre.v experiment. """' "''"^ wO, or 1,000 pounds used in eack rn^:^:r^.7''r::r?^^^^^ f^l^ ^;-^> the combustion wa. the top orifice of the flue a variable quandtvof^h.T ""^ ^.T"".' ^^"^^«^^"^d oflf at When the object is to determine 1^12 ^ T^ difficult to estimate. be introduced through a tube kito the orifice i^tL l ^^eamand other vapors, they mat elevation of temperature in the ^^:r'Jr%7i:^^^ ^^^^^^^^ 820 FUEL. Ill from the quantity of liquid discharged into a measure glass from the bottom outlet c In this case, the furnace is of course removed. Tiie heatin? power of the fuel is measured by the r.ambcr of degrees of tempei-ature which the combustion of one pound of it, raises 600 or 1,000 pounds of water in the bath, the copper substance of the vessel being taken into account. One pound of dry wood charcoal by its combustion causes 6,000 pounds of water to become 20° hottci. For the sai^e of brevity, we shall call this calorific energy 12,000 unities. In like cii^ cumslances, one pound of Llangennoek coal will yield by combustion 11,500 unities of caloric. One pound of charcoal after exposure to the air gives out in burning only 10,500 unities ; but when previously deprived of the moisture which it so greedily im- bibes from the atmosphere, it aflords the above quantity. One pound of Lambton's Wall's-end coals, aflords 8,500 unities; and one of anthracite 11,000. It must be borne in mind that a coal which gives ofl" much unburnt carburetted hy- drogen gas, does not afibrd so much heat, since in the production of the gas a great deal of heat is carried off in the latent state. I have no doubt, that by this distillatory process, from one third to one fourth of the total calorific efl'ect of many coals is dissi- pated in the air. But by means of such a furnace as the patent Argand invention of Mr. C. W. Williams, the whole heat produceable by the hydrogen as well as the carbon is obtained ; and it should be borne in mind that a pound of hydrogen in burning gener- ates as much heat as three pounds of carbon. Mr. Berthier proposes to determine the proportion of carbon in coals and other kinds of fuel, by igniting in a crucible a mixture of the carbonaceous matter with litharge, both finely comminuted, and observing the quantity of lead which is reduced. Foi every 34 parts of lead, he estimates 1 part of carbon, apparently on the principle, thai when carbon is ignited in contact with abundance of litharge, it is converted into car- bonic acid. Each atom of the carbon is therefore supposed to seize two atoms of oxygen, for which it must decompose two atoms of litharge, and revive two atoms of lesui. Calling the atom of carbon 6, and that of lead 104, we shall have the following ratio : — 6 : 104X2 : : 1 : 34.66, being Berthier's proportion, very nearly. On subjecting this theory to the touchstone of experiment, I have found it to be en tirely fallacious. Having mixed very intimately 10 grains of recently calcined char- coal with 1,000 grains of litharge, both in fine powder, I placed the mixture in a crucible which was so carefully covered, as to be protected from all fuliginous fumes, and ex- posed it to distinct ignition. No less than 603 grains of lead were obtained ; whereas by Berthier's rule, only 340 or 346.6 were possible. On igniting a mixture of 10 grains of pulverized anthracite from Merthyr Tydfil, with 500 grains of pure litharge (pre- viously fused and pulverized), I obtained 380 grains of metallic lead. In a second similar experiment with the same anthracite and fttharge, I obtained 450 grains of lead ; and in a third only 350 grains. It is therefore obvious that this method of Berthier is altogether nugatory' for ascertaining the quantity of carbon in coals, and is worse than useless forjudging of the calorific qualities of difierent kinds of fuel. In my researches upon coals, I. have also made it one of my principal objects to de- termine the quantity of sulphur which they may contain ; a point which has been hitherto very little investigated in this country at least, but which is of great conse- quence, not only in reference to their domestic combustion, but to their employment by manufacturers of iron and gas. That good iron can not be produced with a sul- phureous coal, however well coked, has been proved in France by a very costly experi- ence. The presence of a notable proportion of sulphur in a gas coal is most injurious to the gaseous products, because so much sulphuretted hydrogen is generated as to re- quire an operose process of washing or purification, which improverishes the gas, and impairs its illuminating powers by the abstraction of its olefiant gas, or bicarburetted hydrogen. In proof of this proposition, I have only to state the fact, that I found in a specimen of coal gas as delivered from the retorts of one of the metropolitan compa- nies, no less than 18 per cent, of olefiant gas, while in the same gas, after being passed through the purifiers, there remained only 1 1 per cent, of that richly-illuminating gas. By using a gas-coal, nearly free from sulphur, such as No. 4, in the subjoined list, I think it probable that 10 per cent, of more light may be realized than with the common more sulphureous coal. This is an important circumstance which the directors of gas- works have hitherto neglected to investigate with analytical precision, though it is one upon which their success and profits mainly depend. How little attention indeed has been bestowed upon the sulphureous impregnation of pit-coal may be inferred from the fact that one of our professional chemists of note, in a public report, upon a great commercial enterprise, stated that a certain coal analyzed by him was free from sulphur, which coal I found by infallible chemical evidence to contain no less than 7 per cent, of sulphur, being about the double of what is contained in English coals of average quality. The proportion of sulphur may in general be in- ferred from the appearance and quantity of the ashes. If these be of a red or ochrey color, and amount to above 10 per cent., we may be sure that the coal is eminently > FUEL, 821 snlphureous. The coal above referred to afforded from 15 to 16 per cent, of ferrugin- ous ashes. I believe that sulphur exists in coal generally, though not always in the state 01 pyrites, either in manifest particles, or invisibly disseminated through their substance. The readiest method of determining rigidly the quantity of sulphur in anv compound, is to mix a given weight of it with a proper weight of carbonate of potassa, nitre, and common salt, each chemically pure, and to ignite the mixture in a platinum crucible. A whitish mass is obtained, in which all the sulphur has been converted into sulphate 01 potassa. By determining with nitrate of baryta the amount of sulphuric acid pro- duced, that of the sulphur becomes known. By means of this process applied to dif- ferent samples of coals, I obtained the following results :~ Gas Ci>ais. No. 1 2 3 4 Sulphur in 100 parts. 3-00 3-90 2-42 3-80 Gas Coals. No. 5 6 7 8 Sulphur in 100 parts. 2-50 5-20 3-40 3-50 Coals for puddling cast iron, to be converted into steel, No. 1, hard foliated or splent coal, specific gravity 2, ditto 3, ditto -------. 4, cubical and rather soft - - - _ 1-258 1-290 1-273 1-267 Sulphur ia 100 parts. 0-80 0-96 3-10 0-80 1-57 4-82 3-25 10-5 Tht lasv coal being rich in bitumen, would prove an excellent one for the production ofa pure coal gas. See Pitcoal. FUEL, ECONOMY OF. In the report of the Transactions of the Institution of Civil Engineers for February, 1838, the results of exact comparisons between the per- lormance of difierent steam-engines exhibit this economy in a remarkable manner It la there shown that a condensing engine of the most perfect construction, and in peifect condition, of the common low pressure crank-kind, not working expansively, performs a duty of not more than 20 or 21 millions of lbs. raised one foot high, by 90 or 94 lbs of coal ; or ten lbs. of coal per horse power per head. The following table exhibits the relative value of diflTerent engines in lbs. of coalner horse power per hour : — 01*/^* Cornish Pumping Engine - - - - _ Bolton and Watt's Single Engine - - - - Cornish Double Engine ..... Bolton and Watt's Double Engine The greatest duty performed by the measured bushel of 84 lbs. was 86| millions of lbs. There was raised by the Huel Towan engine in Cornwall 1,085 tons (of waters one foot high for one farthing. Hence the weight of a man (l^ cwt.) would be raised ten miles for one penny ! v -« / «iacu In order to raise steam with economy, the surface of water in the boiler, exposed to the fare, ought not to be less thon 10 square feet per horse power ; but the usual allow- ance in Lancashire is only 7^; and by Messrs. Boulton and Watt, 5 square feet The values of the mean of the Cornish, Warwick, London, Lancashire, and loco- motive experiments, as reported by Mr. Josiah Parkes, were respectively 21 18 13i and^K) cubic feet of water evaporated by 112 lbs. of coals, from water heat'ed to FUEL GRANT'S PATENT This fuel is composed of coal-dust and coal-tar pitch ; these materials are mixed together, under the influence of heat, in the following Rrop<,rtions :-20 lbs. of pitch to 1 cwt. of coal-dust, by appropriate machinery^ consisting of crushing-rollers for breaking the coal in the first instance sufiiciently small, so that it may pass through a screen the meshes of which do not exceed a quarter oLo" '.''u f ""^^'•5 2dly, of mixing-pans or cylinders, heated to the temperature of 220 , either by steam or heated air; and, 3dly, of moulding machines, by which the fuel IS compressed, under a pressure equal to five tons, into the size of a common biick . the fuel bricks are then whitewashed, which prevents their stickin? together, either ir the coal bunkers or ,n hot climates. The advantages of Grant's fuel over even the best coal may be stated to consist, first, in its superior efficacy in generating steam, which may be thus stated— 200 tons of this fuel will perform the same work as 30l tins of coal, such as are generally used ; secondly, it occupies less space; that is to say, 500 tons of It may be stowed in an area which will contain only 400 tons of coal; thirdly, it is used with much greater ease by the stokers or firemen than coal, and it creates little or no dirt or dust, considerations of some importance when the delicate machinery of a steam-engine is considered; fourthly, it produces a very small propor tion of clinkers, and thus it is far less liable to choke and destroy the furnace bars and 822 FUEL. « J- II bcHlers than coal ; fifthly, the ignition is so complete that comparatively little smoke, and only a small quantity of ashes, are produced by it ; sixthly, from the mixture of the patent fuel, and the manner of its manufacture, it is not liable to enter into spontaneous ignition. Fuel chiefly Pit Coal. " Considering the vast importance of the subject, it is somewhat remarkable that no exact mode of determining the true value of coal as a fuel has ever yet been invented. Of the methods hitherto in use there is not one which deserves the title even of an approximation to the truth. The plan of Berthier, as has been well shown by Dr. Ure, is beyond all things fallacious, though this very plan is that most relied on by the experimenters connected with the late Admiralty investigation re- specting the coals best suited for the steam navy. It needs, however, but a moment'9 reflection to see that this process of Berthier can never afford a correct result, for the agent employed is litharge, a substance not acted on at all until exposed to heat more than auflScient for the expulsion of the volatile constituents of coal, and moreover a substance capable of being reduced at high temperatures by the carbonic oxide gas of the fire employed to eflFect the assay. Here then are two enormous sources of error ; for in the first place the hydrogenous constituents of the coal can never be estimated at all, and in the second the litharge by mere exposure in a crucible to the action of the fire will give metallic lead exactly the same as if coal existed in it, so that not the least dependence in the world can be placed in this method. Numerous and carefully conducted experiments have fully confirmed the original observations of Dr. Ure upon this matter, and, in fact, the results from four crucibles, each charged with the same quantities of coal and litharge, taken from the same massive powder, and placed side by side in the same furnace, and treated in all respects exactly alike, have shown a discordance equal to the numbers 117, 142, 166, and 163. To think of attaching any value to any of these, or to the average which they present, is to lose sight of the most important province of chemistry in its relation to the arts. " Another, and certainly a preferable method, is to consume a given amount of each coal in a calorimeter, so as to measure the total heat disengaged during combustion. But here, again, we meet with diflficulties more than enough to destroy all confidence in the results. Thus it is not possible thoroughly to consume the whole of the fuel in thia way. Of the volatile constituents of the coal, a portion always passes off unbumt in the shape of carburetted hydrogen, tar, and soot, whilst of the carbou or fixed constituents, part is constantly lost in the form of carbonic oxide gas. So that no real estimate of the calorific value of a coal can be arrived at in this way, and even comparative experiments are worthless from the great inequalities which prevail in the ratio of the volatile and fixed ingredients in different coals, as well as from the changes induced by accidental variations of draught through the. body of the fuel Of course the same objections apply to what are called practical experiments, conducted with any one particular form of furnace or setting of a boiler. The form of furnace, as is well known, requires to be adapted to the fuel, and not the fuel to the furnace : nevertheless, m the Admiralty experiments already alluded to, the only f»rm of furnace and boiler employed was that called the Cornish setting, though this particular form was expressly invented for, and will, as is notorious, do justice to no other kind of coal than anthracite. Hence the parliamentary reports which chronicles the results of the Procrustean theorem, though yet almost wet from the press, is even now rapidly on its road to the butter- shop, there to expiate, by the humblest of services, its previous utter inutility to the public. To know the precise amount of heat evolved from coals during their com- bustion, must, as has been before remarked, be a subject of the greatest possible interest, for until the total calorific power be taken into account, it is impossible for ua to appreciate the loss which ensues under the existing modes of consuming fuel At present it seems generally agreed, that ordinary Newcastle coal will evaporate about 8 times Its weight of water, or in other words, that a ton of such coal will boil off or con vert into steam 17,920 lbs. of water. If, however, we proceed to a practical analysis of this very coal, by examining the heating power of its gaseous and fixed constituents after these have been separated from each other, we shall find that the above is very fai short of the most moderate estimate that can be formed of the heat which must be dis- engaged ; and whether the difference be lost by imperfect combustion, or by the action of the chimney, or in what other way, remains stQl to be decided by those who seek to improve our present modes of consuming fuel. The following table represents the actual heat evolved, and of water evaporated, by the different constituents of one ton of the Newcastle coal called Pelton ; and it must be remembered, that so far as chemical research has yet gone, the heat evolved from a combustible is in proportion to the amount of oxygen consumed, and has no connection with the particular mechanical state of the combustible. For instance, there is no reason to supposie that gaseous carbon, if we possessed such a substance, would evolve either more or less heat than its Muivalent weight of solid carbou, in combining with the same quantity of o.xygen gas. Whether, therefore, we regard the constituents of coal as existing in the solid or gaseous I . FUEL. 823 form, does not, according to our present knowledge, alter the proportion of heat which these constituents would give out during their perfect oxidatioa Now one ton of Pelton coal affords 10,000 cubic feet of gaseous matters, 10 gallons or about 126 lbs. of tar, and 41 bushels or 1680 lbs. of coke ; and, by experiment, it has been found that the above gas before purification will boil oflf for every cubw foot consumed 10^ ounces of water ; that 3 gallons of tar are equal to about one bushel of coke ; and that the coke will boil off 10 times its weight of water Hence we have the total amount of water evaporated as under : 10,000 cubic feet of gas at 10^ ounces per foot = 6537 lbs. 10 gallons of tar equal to 333 bushels of coke = 1365 lbs. 1680 lbs. of coke at 10 lbs. per lb. - - = 16800 lbs. Total 24702 or upwards of 1 1 lbs. of water for every lb. of coal. It happens, however, that even thia estimate is too low, and that actual experiments on this very coal shows its true heating power to be not less than 12. To elucidate this it becomes necessary, however, to enter into an explanation of the means employed for ascertaining the precise amount of heat evolved by any combustible during its complete oxidation, and which is perhaps the only approach to accuracy that has yet been proposed with this view. A copper vessel, shaped like a parallelogram, and having in its ends two small openings provided with stop cocks, has also in its lower surface a large opening of two inches in diameter, terminating in a tube or neck of about two inches in length and fitted with an earthen- ware plug or stopper. This parallelogram is enclosed in another and larger one capable of holding m addition 20 lbs. of water. The smaller vessel should have an internal capacity of about half a cubic foot, or 800 cubic inches, and the different openings must pass out of and through the larger vessel. The earthenware stopper is to be provided with two small openings, in which pass two insulated copper wires, and on the top of the stopper IS a cavity capable of holding 50 grains of coal in coarse powder, throu«-h which a fine platinum wire passes connected with the terminal ends of the two aipper wires, and over the whole a cage of stout platinum wire is placed so as to prevent the coal from being thrown out during the experiment, and also to insure the complete combustion of all the volatile and fuliginous matter. To use this apparatus, 60 grains of the coal in quejition are placed in the cavity of the stopper, and the necessary connections beinxr made by means of a fine platmum wire, the cage is applied, and the whole inserted in tlie neck or opening left for it, and which it hermetically closes : as soon as this is com- pleted, a current of oxygen gas is made to traverse the smaller vessel by means of the stop-cocks in the sides, and this is continued until the atmospheric air bein"- almost wlioUy expelled, the vessel remains full of oxygen gas ; when this is the case water must be poured into the larger vessel, and a piece of ice introduced into it until the tempera- ture has fallen about 6° below that of the apartment, when the ice must be withdrawn and the coal lighted by means of a small galvanic battery, the poles of which need be applied but for a moment to the copper wires which pass through the earthenware stopper. Ignition instantly ensues, and is finished in two or three seconds, when the heat of the water in the larger vessel must be ascertained by a delicate thermometer after proper agitation. It is of course necessary to take the usual precautions followed in experiments of this kind, and to surround the whole of the larger vessel by non-con- ductors of caloric, having carefully determined beforehand the absorption of heat due to the apparatus, so that this may be added to that of the water • the water itself should either be actually weighed or measured with great accuracy at a mean temperature and the ice must also be weighed before and after immersion. The accompanying sketch in section will perhaps facilitate the comprehension of this instrument ^ -^ ^ *A, cover made of wood; b, lai^er vessel of copper; c, smaller vessel of copper ; d, entrance for oxygen gas ; K, exit for atmospheric air^ f, plati- num cage ; g, earthenware stopper with cavity in top; h h, copper wires for conveying electricity, between the upper extremities of which a fine pla- tinum wire is loosely stretched which passes through the mass of powdered coal. The results hitherto obtained by this apparatus are not very extensive, but nevertheless they embrace sub- ■ 824 FUEL. stantiallj many of the best established coals, and as might d priori he imagined, they moreover demonstrate in an undeniable manner the superiority of bituminous over antbra- citic coals and coke,— a position directly the reverse of the absurd assumptions and foregone conclusions contained in the parliamentary report of Sir H. de la Beche and Dr. Playfair. The following is a tabular view of these results, with a column showing the evaporative power of each, deduced by assuming 980 as the latent beat of steam. Newcastle : Pelton - Garesfield (Bates) Hastings Hartley- West Hartley - Bates Hartley - Newcastle Hartley Heat on - Gosford - Killingworth - Durham: Hetton • Lambtoo Rainton - YORKSHIKE : Woodthorpe - Mortemly North "Wales : Brymbo - Ruabon - South "Wales : Anthracite No. 1. Anthracite No. 2. Neath (Bituminous) Ireland : Anthracite "WlGAN : Cannel Ince Hall Scotch: Lesmahago Cannel - Newcastle : Ramsev's Cannel Unities of Caloric. Lbs. of "Water caiMble of being evaporated by 1 lb. of Coal. 14800 15200 16175 16280 15985 16330 15075 16000 14875 15660 15460 14995 13780 14010 13876 14200 13090 12875 18845 12990 14340 12285 14420 lbs 151 15 5 16-6 16-6 16-3 16-6 15-6 158 151 160 15-7 15-3 14-0 14-3 141 145 13-3 131 140 18-2 — 14-6 — 12 5 — 14-7 — Comparing these results with the actual working of most of the above bituminous coals, it appears that very nearly one half of all the heat evolved is lost in practice, and either passes off in the shape of unconsumed fuel, or is wasted in the chimney. With a view to ascertain how much of the loss is due to this latter circumstance, Mr. F. J. Evans, the eminent engineer of the Westminster station of the Chartered Gas Company, made some time ago an experiment bearing upon this subject, and in which the loss of heat is necessa ily very high, from the fact that the substance heated by the fiirnnce was almost white hot, whereas in a steam boiler the temperature never exceeds 300° of Fahr. Mr. Evans's experiment, which shows no trifling anK)unt of ingenuity, nevertheless demon- strates that not more than 3 per cent, of the fuel passes off by the heat of the chimney ; consequently at least 15 times this amount must be lost by im'perfect combustion, and fly away in the shape of carburetted hydrogen, tarry vapour, or carbonic oxide; thus leav- ing a wide field for improvement in burning and applying fuel. We give the following in Mr. Evans's own words. .* U FUEL. 826 *' * Experiments on waste heat : to determine the quantity of heat going away to the chimney from a setting of 8 retorts. A deal box was constructed of the following dimen- sions ; jfength 5 feet 6 inches, width 11 inches, and depth 7 inches, and quite water-tight Within this box, and running through it, was placed an iron tube of the following dimen- sions ; length 81 inches, width 9 inches, depth 3 inches. This tube formed by subsequent arrangement a portion of the flue through which the air from the furnace passed to the chimney, as is shown in the sketch below, where a represents an iron plate closing the main flue, and compelling the hot air to pass through the iron tube contained in th^ wooden box, into which water was ultimately placed, as will be explained. V!!!Je^fei^^^>y^J^^.>-../>l^^/.-^ i y^ I MAIN \ I V I WOODEN BOX ,.MM^'^M2fJ2W}M>>JMJ....MJjmy>J»J^»^^^^^^ FLUE ii))}jy ij ' rffwvj^f^rr^ 'rtM.-,,,W^^.fl^' f X FOR WATER IRON TUBt OR TCMFORART FLUE _ ,J^^,,,,,^,,,,,,,,,,l>in»>ll»>tll>l>milUMn^,,%m.,,,,,,,•l•<>>>llln.^,yTr,frfm ===A ** • Matters being thus arranged, and the iron plate at a securely fixed, it necessarily- followed that all the heat from the setting of 8 retorts passed through the 81 inches of iron tube contained in the box, and would therefore impart heat to the water placed in that box, which was filled with this fluid at 71° Fahr. to the extent of 112 lbs. Thia water being kept in constant motion afforded the annexed thermometric indications. Commenced experiment at 6*45 Observation made at 648 6-51 • 6-54 « 6'57 « 7-01 " 706 « 707 Temperature of water. 71° . 88 - 94 - 110 - 114 - 132 - 148 - 150 Thus showing that 112 lbs. of water were raised 89° in 22 minutes, which is equal to 2-62 lbs. of water at 32° made to boil in each minute. Consequently in 24 hoars 8628-8 lbs. of such water might be made to boil, or 6041 lbs. of water be converted into steam in the same period of time, and as coke will evaporate, according to Lavoisier, more than 10 times its weight of water, this implies the consumption of nearly 60^ lbs* of coke, the heat of which is entirely lost in the chimney. And if this be compared with the total coke consumed for 24 hours in the same setting of retorts, it amounts to about 3 per cent, only, and is therefore under the circumstances remarkably trifling.* Hence it would appear, as has been before remarked, that some very considerable improvements are needed in the present mode of consuming bituminous coals. The pro- bability is, that a flat boiler surface exposed freely to a single sheet of flame from such coals is the best form, for it is certain that long narrow flues act like the meshes of wire gauze upon the volatile constituents, and cool them down below the point at which Ignition can go on. In support of this view we have only to recollect that though the gases from a blast furnace will burn freely when they first issue from the fur- nace and are white hot, yet after being once cooled down to the ordinary tempera- ture they refuse altogether to burn or afford heat. The use of long and narrow flues, with combustibles of low accendibility, is therefore highly improper, and suffi- ciently explains the miserable results arrived at by the Admiralty coal investigatong with a Cornish boiler." — Mr. L. Thompson. FULGURATION ; designates the sudden brightening of the melted gold and silver in the cupel of the assayer, when the last film of vitreous lead and copper leaves their surface. FULLER'S EARTH, {Terre a foulon, Argile Smectique, Fr. ; Walkererde, Germ.) is a soft, friable, coarse or fine grained mass of lithomarge clay. Its colour is greenish, or yellowish gray ; it is dull, but assumes a fatty lustre upon pressure with the fingers, feels unctuous, does not adhere to the tongue, and has a specific gravity varying from 1-82 to 219. It falls down readily in water, into a fine powder, with extrication of air bubbles, and forms a non-plastic paste. It melts at a high heat into a brown slag. Its constituents are 53-0 silica; 100 alumina; 9*75 red oxide of iron; 1-25 magnesia; 0'6 lime; 24 water, with a trace of potash. Its cleansing action upon woollen stuffs depends upon its power of absorbing greasy matters. It should be neither tenacious nor sandy ; for in the first case, it would not diffuse itself well through water, 826 FULLING MILL. and in the second it would abrade the cloth too much. The finely divided silica is one of its useful ingredients. Fuller's earth is found in several counties of England; but in greatest abundance in Bedfordshire, Berkshire, Hampshire, and Surry. In the county of Surry there are great quantities of fuller's earth found about Nut- field, Ryegate, and Blechingley, to the south of the Downs, and some, but of inferior quality, near Sutton and Croydon, to the north of them. The most considerable pits are near Nutfield, between which place and Ryegate, particularly on Redhill, about a mile to the east of Ryegate, it lies so near the surface as frequently to be turned up by the wheels of the wagons. The fuller's earth to the north of the road between Red- hill and Nutfield, and about a quarter of a mile from the latter place, is very thin ; the seam in general is thickest on the swell of the hill to the south of the road. It is not known how long this earth has been dug in Surry ; the oldest pit now wrought is said to have lasted between 50 and 60 years, but it is fast wearing out. The seam of fuller's «arth dips in different directions. In one, if not in more cases, it inclines to the west .vith a considerable angle. There are two kinds of it, the blue and the yellow ; the former, on the eastern side of the pit, is frequently within a yard of the surface, being covered merely with the soil— a tough, wet, clayey loam. A few yards to the west, the blue kind appears with an irony sand-stone, of nearly two yards in thickness, between it and the soil. The blue earth in this pit is nearly 16 feet deep. In some places the yellow kind is found lying upon the blue ; there seems, indeed, to be no regularity either in the position or inclination of the strata where the fuller's earth is found, nor any mark by which its presence could be detected. It seems rather thrown in patches than laid in any continued or regular vein. In the midst of the fuller's earth are often found large pieces of stone of a yellow color, translucent and remarkably heavy, which have been found to be sulphate of barjtes, encrusted with quartzose crystals. These are carefully removed from the fuller's earth, as the workmen say they often spoil many tons of it which lie about them. There is also found with the yellow fuller's earth a dark brown crust, which the workmen consider as injurious also. In Surry the price of fuller's earth seems to have varied very little, at least for these last 80 years. In 1730, the price at the pit was 6d. a sack, and 6*. per load or ton. In 1744, it was nearly the same. It is carried in was:ons, each drawing from three to four tons, to the beginning of the iron railway near Westham, along which it is taken to the banks of the Thames, where it is sold at the different wharves for about 25*. or 26*. per ton. It is then shipped off either to the north or west of England. The next characteristic stratum, owing to its forming a ridge of conspicuous hills through the country, is the AVoburn land, a thick ferruginous stratum, which below its middle con- tains a stratum of fuller's earth. This is thicker and more pure in Aspley and Hogstyc- end, two miles north-west of Woburn, than in any known place. Fuller's earth is found at Tillington, and consumed m the neighboring fulling mills. Mode of preparing fuller's earth : — After baking it is thrown into cold water, where it falls into powder, and the separ- ation of the coarse from the fine is effectually accomplished, by a simple method used in the dry color manufactories, called washing over. It is done in the following manner: Three or four tubs are connected on a line by spouts from their tops; in the first the earth is beat and stirred, and the water, which is continually running from the first to the last through intermediate ones, carries with it and deposites the fine whilst the coarse settles in the first. The advantages to be derived from this operation are, that the two Kinds will be much fitter for their respective purposes of cleansing coarse or fine cloth ; for without baking the earth they would be unfit, as before noticed, to incorporate so minutely with the water in its native state ; it would neither so readily fall down, nor so easily be divided into different qualities, without the process of washing over. When fuel is scarce for baking the earth, it is broken into pieces of the same size, as mentioned above, and then exposed to the heat of the sun. The various uses of fuller's earth may be shortly explained. Accordinar to the above method, the coarse and fine of one pit being separated, the first is used for cloths of an inferior, and the second for those of a superior quality. The yellow and the blue earths of Surry are of different qualities naturally, and are, like the above, obtained arti- ficially, and used for different purposes. The former, which is deemed the best, is employed in fulling the kerseymeres and finer cloths of Wiltshire and Gloucestershire, whilst the blue is principally sent into Yorkshire for the coarser cloths. Its effect on these cloths is owing to the aflinity which alumine has for greasy substances ; it unites readily with them, and forms combinations which easily attach themselves to different stuffs, and thereby serve the purpose of mordants in some measure. The fullers generally apply it before they use the soap. FULLING; for the theory of the process, see Felting and Wool. FULLING MILL. Willan and Ogle obtained a patent in 1825 for improved ful- I ■ FULMINATES. 827 66Y ling machinery, designed to act in a sim- ilar way to the ordinary stocks, in which cloths are beaten, for the purpose of wash- ing and thickening them ; but the standard and the bed of the stocks are made of iron instead of wood as heretofore; and a steam vessel is placed under the bed, for heating the cloths during the operation of fulling ; whereby their appearance is said to be great- ly improved. Fig. 667 is a section of the fulling machine or stocks ; a is a cast-iron pillar, made hollow for the sake of lightness ; b is the bed of the stocks, made also of iron, and polished smooth, the side of the stock being removed to show the interior ; c is the lever that carries the beater d. The cloths are to be placed on the bed (, at bottom, and water allowed to pass through the slock, when by the repeated blows of the beater p^roxyde 76-0 Oxygen ^ 5-b > Fulminic acid - - 24 1000 Question 3. May the gas or vapor produced by the inflammation of the fulminate of mercury, when combined with a portion of gunpowder, be considered in its nature corro- "^^T^trer!" Thav? suggested to Mr. Lovell, of Waliham Abbey works, that the ful- minate may be probably diluted most advantageously with spirit varnish made o a proper consistence by dissolving sandarach in alcohol. When well mixed with this varnish, a small drop of the mixture will suffice for priming each copper cap or disc; and as the spirit evaporates immediately, the fulminate will be fixed to the copper beyond the risk of shaking or washing away. On the Continent, tincture of benjamm is used for the same purpose ; but as that balsamic resin leaves in ^o/nbustion a volu- minous coal, which sandarach does not, the latter, which is the mam «««« f "^»'J^f spirit varnish, seems better adapted for this purpose. It is sufficiently combustible, and may be yet m'ade, by a due proportion, to soften the violence of the explosive mercury on the nipple of the touch-hole. Fulminate prepared by my fornjula has no con-osive influence whatsoever on iron or steel; and, therefore, if such a medium of applying it, as I have now taken leave to suggest, should be found to answer, all fears on the score of corrosion may for ever be set at rest. ^ „ , . , j m- vi« t^Ko offr./.to/i Quesfion 4. How far is the mixture (of fulminate and gunpowder) liable to be affected by the moisture of the atmosphere, or by the intrusion of water; and will such an acci- dent affect its inflammability when dried agam ? . , , , ,„„„„ „„ jlnsvoer. Well made fulminate, mixed with gunpowder and moistened, undergoes no change, nor is it apt to get deteriorated by keeping any length of time in a damp climate or a hazy atmosphere. Immersion in water would be apt to wash the nitre out of the pulvertne; but fhis result would be prevented if the match or priming mixture were liquefied or brought to the pasty consistence, not with water, but spirit varnish. Such detonating caps would be indestructible, and might be alternately moistened and diied ^'q^tiam' Is it at all probable that the composition would be rendered more inflam- mable or danirerous of use by the heat of tropical climates ? jltiswer. No elevation of temperature of an atmospheric kind, compatible with hu- man existence, could cause spontaneous combustion of the fulminating mercury, or the detonating matches made with it. In fact, its explosive temperature is so high as 367- of Fahrenheit's scale, and no inferior heat will cause its detonation. Question 6. Is the mercurial vapor or gas arising from the ignition of a great number of primers, and combined with the smoke of gunpowder in a confined space (as in the case of trcips in close bodies, squares, casemates, &c.), likely m its nature to be found oreiudicial to human health ? ^ . /. r i • #- «i JSnswer I have exploded in rapid succession of portions, 100 grains of fulminate ol mercury (equivalent to 300 or 400 primers), in a close chamber of small d»jnens»o««J without exneriencing the slightest inconvenience at the period, or afterwards, though my held was surrounded by the vapors aU the time of the operation. These vapors are, m fact%rhe;Tthat they'subside'almost immediate^^ When the ruhninate mixed wih nulverine is exploded in the primers by condensed masses of troops, the mercary wiii Lte no /nju^/to their health nor 100th part of the deleteho'is. impressi^^^^^^^ lungs which the gases of exploded gunpowder might by Ppssibihty inflict These g^e. are all, theoretically speaking, noxious to respiration ; such as carbonic f^J^ ?a^^^^^ carbureted hydrogen, and sulphureted bydrosen a deadly gas. Yet the s^^^^^^^^ who •hould betray any fear of gunpowder smoke would be an object of just ridicule. FULMINATES. 831 In the following September, I executed for the Board of Ordnance a set of experi- ments, complementary to, those of the memoir, with the view of ascertaining the best manner of protecting the fulminate when applied to the copper caps, from being detached by carriage, or altered by keeping. The following were my results and con- clusions. 1 V 41. « 1. Fulminate of mercury moistened upon copper is speedily decomposed by the superior affinity of the copper over mercury, for oxygen and fulminic acid. Dryness is, therefore, essential to the preservation of the fulminate; and hence charcoal, which is apt to beci.me moist, should not be introduced into percussion caps destined for distant service 2. An alcoholic solution of sandarach, commonly called spirit varnish, acts power- fully on copper, with the production of a green efflorescence, which decomposes ful- minate of mercuiy. Indeed, sandarach can decompose the salts of copper. It is there- fore ill adapted for attaching the fulminate to copper caps. 3. An alcoholic solution of shellac acts on copper, though more feebly than the sandarach. ^ , , , . , ... r i • 4. A solution of mastic in spirits of turpentine, whether alone or mixed with lulmi- nate, has no action whatever on bright copper, but protects it from being tarnished. Suck a varnish is very cheap, dries readily, adheres strongly, screens the fulminate from danapj and does not impair or counteract its detonating powers. This, therefore, is, in my opin- ion, the fittest medium for attaching the fulminate, and for softening the force of its im- pulsion in any degree preporlional to the thickness of the varnish." Fulminate of mercury is obtained in white grains, or short needles, of a silky lustre, which become gray upon exposure to light, and detonate either by a blow or at a heat un- der 370° F. ; with the disengagement of azote, carbonic acid, as also of aqueous and mer- curial vapors ; to the sudden formation of which gaseous products the report is due. It detonates even in a moist condition ; and when diy it explodes readily when struck between two pieces of iron, less so between iron and bronze, with more difficulty between marble and glass, or between two surfaces of marble or glass. It is hardly possible to explode it by a blow with iron upon lead ; and impossible by striking it with iron upon wood. It fulminates easily when rubbed between two wooden surfaces ; less so between two of marble, two of iron, or one of iron against one of wood or marble. The larger its crys- tals, the more apt they are to explode. By damping it with 5 per cent, of water, it be- comes less fulminating; the part of it struck still explodes with a proper blow, but will not kindle the adjoining portion. Though moistened with 30 per cent, of water, it will occasionally explode by trituration between a wooden muller and a marble slab, but only to a small extent, and never with any danger to the operator. When an ounce of it, laid upon the bottom of a cask, is kindled, it strikes a round hole down through it, as if it had been exposed to a four-pound shot, without splintering the wood. If a tram of ful- minate of mercury be spread upon a piece of paper, covered with some loose gunpowder, in exploding the former the latter will not be kindled, but merely scattered. When gun- powder, however, is packed in a cartridge, or otherwise, it may be certainly kindled by a percussion cap of the fulminate, and more completely than by a priming of gunpowder. 8* parts of gunpowder exploded by a percussion cap, have an equal projectile force as 10 exploded by 'a flint lock. If we add to this economy in the charge of the barrel, the saving of the powder for priming, the advantage in military service of the percussion system will become conspicuous. . . i i -i ni iv i v The French calculate that 1 kilogramme of mercury will furnish IJ kil. (2t lbs. nearly) of fulminate, which will be sufficient to charge 40,000 percussion caps. For this pur- pose they grind the crystalline salt along with 30 per cent, of water upon a marble table with a wooden muller; mixing with every 10 parts of the fulminate 6 of gunpowder. A consistent dough is thus obtained, which, being dried in the air, is ready for introducing into the bottoms of the copper caps. One quarter of a grain of the fulminate is said to be fully sufficient for one priming. . . , . Mr. Lovell, of the Royal Manufactory of Arms, has lately executed a series ot experi- ments upon priming powders. His trials, which occupied nearly 18 months, were made for the purpose of ascertaining what is the advantage in point oi" force obtained by using percussion primes. He had anticipated some extra energy would be imparted to the charge of powder in the barrel, because he had repeatedly proved that a good strong cap, exploded by itself on the nipple of the musket (without any charge of gunpowder), will exert sufficient force upon the air within the barrel to blow a candle out at a distance of 12 feet from the muzzle. He concluded also that stopping the escape of fluid from the vent as is done by the cap, would have some effect, but he attributed most to the quick- ness 'and energy with which the powder of the charge is ignited by the vivid stream of flame, generated by the percussion prime. The trials were made from one and the same barrel, having a percussion lock on one side and a flint lock on the other. The balls were fired against Austen's recoiling target, a very delicate ;)/egom« Potassium +58° Sodium 90 Tin 210 Bismuth 256 Lead 260 Tellurium A little less fusible than lead. — ^Elaproth. Arsenic Undetermined. Zinc 370° Brongniart. Antimony A little below a read heat. Cadmium Stromeyer. Pyrometer of Wedjewood. Gay Lussac and Thenard. Newton. Biot. Silver Copper Gold Cobalt Iron Manganese Nickel Palladium Molybdenum Uranium Tungsten 20 Kennedy. 27 ) 32 < Wedgewood. A little less diflicult to melt than iron. 130 Wedgewood. 158 Sir G. M'Kenzie. 160 Guyton. As manganese. — Richter. Nearly infusible ; and to be obtained at * forge heat only in small buttons. Infusible at the forge furnace, the oxyhydrogen blowpipe. FIP£. Fusible a\ See Blow- Chromium Titanium Cerium Osmium Iridium Khodium Platinum Colambium J FUSIBLE METAL. See Alloy. FUSTET. (Fuslec, Fr.) The wood of the rhus cotinus, a fugitive yellow dye. FUSTIAN is a species of coarse thick tweeled cotton, and is generally dyed of aa olive, leaden, or other dark color. Besides the common fustian, which is known by the name of pillow (probably pilaw), the cotton stuffs called corduroy, velverett, velveteen, thicksett, used for men's wearing apparel, belong to the same fabric. The commonest iund is merely a tweel of four, or sometimes five leaves, of a very close stout texture, and very narrow, seldom exceeding 17 or 18 inches in breadth. It is cut from the loom in half pieces, or ends, as they are usually termed, about 35 yards long, and after under* going the subsequent operations of dyeing, dressing, and folding, is ready for tb^ market I FUSTIAN. 835 The draught and cording of common fustian is very simple, being generally a regular or unbroken tweel of four or five leaves. Below are specimens of a few different kinds, selected from those most general in Lancashire. The number of leaves of heddles are represented by the lines across the paper, and the cording by the ciphers in the little squares, those which raise every leaf bein? distin- guished by these marks, and those which sink them left blank, as more particularly explained in the article Textile Fabric. Of velvet, there are properly only two kinds, that with a plain, and that with a tweeled, or, as it is here called, a Genoa ground, or back. When the material is silk, it is called velvet, when cotton, velveteen ; and this is the sole difference. In the same way a com- mon twceled cloth, when composed of silk is called satin ; when of cotton, fustian oi jean • of woollen, plaiding, serge, or kerseymere ; and in the linen trade is distinguished by a variety of names according to the quality or fineness, or the place where the article is manufactured. XVp. 1. — Pillow Fustian. No. 2.- -Plain Velveret. iO| i 1 1 4 5 1 ♦ 1 |0| 1 1 i 3 1 " 1 I0| 1 1 9 6 * |0I 1 1 1 1 5 ~ 1 1 |0| |6 2 3 « |0| 1 |0|0| 2 ^■" • 1 1 1 I0| 5 1 4 ^ 1 1 1 |0| 1 6 4 ~ 2 4 3 1 4 6 2 3 1 Of the above, each contains four leaves of heddles or healds ; that represented by No 1 IS wrought by four treddles, and that which is distinguished by No. 2 by five ; the suc- cession of inserting the threads of warp into the heddles will be discovered by the figures between the lines, and the order in which the treddles are to be successively pressed down by the figures below. No. 3. — Double Jean. No. 4.— Plain Thickset. o| 10 (> I0| 2 I I0|0| I J_l|O|0|O| I 6 4 I |0| |0| 4 ^ III 4 2 3 1 « 0| U |0 3 I 4 6 1 7 These, like the former, are wrought with leaves. No. 3 requires four, and No. 4 fire treddles. The succession of inserting the threads of warp, and of workin? the treddles, are marked by the respective numbers between and under the lines, as in the former example. Both are fabrics of cloth in very general use and estimation as low priced- articles. No. 5.— Best Thickset. No. 6.— Velvet Tuft. |0i |0|_0_ » I |Q| 1115 1 » I |0|0| I I 4 2 .1 I0|0| I I 6 4 2 3 5 « 0|0| 1 I I I |0| I 6 4 2 3 1 3 I These are further specimens of what may be, and is, executed with four leaves, and in both examples five treddles are used. With two other specimens we shall conclude our examples of this description of work, and shall then add a very few specimens of the more extensive kinds. No. 7.--Cord and Velveret. No. 8.— Thickset Cord. I 101 I I I I I0|0| I I 5 |0| I |0|0| 6 I I I |Q| 1 4 3 1 (, |0| I loioi" I I0| I I I I I I I I I 4 2 3 1 6 5 ± » I I0|0| I I 5 4 3 2 1 9 7 10 8 6 In these the succession of drawing and working are marked like the former. The next are examples of patterns wrought with six leaves. No. 9 has eight, and No. 10 five neddles. 836 FUSTIAN. No. 9.— Double Coriuroy. No. 10. — Genoa Thickset. I I I iO| |0| i» I |oi I I !0| I I I 0|0|0|0| \ I Tl I iO| io| I I MM l"i I I I 01 u o| |0|0| I |0| |0|0| 0| |0| |0| |0 2 4 6 8 10 12 3 1 7 5 11 9 4 2 5 3 1 8 6 11 9 7 1 2 10 !• In both these the warp is inserted into the heddles the same way. The difference is enliiely in the application of ihe cords, and in the succession of pressing u^wn the treddles. We now give four specimens of the flushed and cut work, known by the name of velveteen. They are also upon six leaves, and the difference is solely in the cording tad in the treading. No. 11. Queen's Velveteens. No. 12. I |0| |U|0| i f) I I |o|0| I I I I I 10 10 Id I I |0| |0| I |01 |0|0| I I I IQJ |01 |0| |010| |0|0| o| |0| |o| I |0|0| |0|0| 1 2 12 8 4 2 5 7 6 9 11 10 No. 13. — Plain Velveteen. 2 4 3 6 8 7 10 12 11 9 1 No. 14. — Genoa Velveteen. 1 I I'M I |0| I |0| |0|0| I 1 I |0| u I |0|0| |0 0|0 0|0| |0| I |0|0| |0|0| |0j |0| 3 7 4 8 2 6 10 8 12 3 i 11 The additional varieties of figure which might be given are almost endless, but the limits of this article will not admit a further detail. Those already given are the articles in most general use. The varieties of fancy may be induked to a great extent; but it is aniversally found, that the most simple patterns in every department of ornamental weaving are those which attract attention and command purchasers. We shall therefore only add two examples of king's cord or corduroy, two of Genoa and common velvet, and two more of jean. These will be found below. No. 15.— King's Cord. No. 16.— Dutch Cord. 1 1 1 1 \^\^\ 1 2 1 1 1 1 |0| 0| 1 1 4 1 1 1 |0| 1 |0| 1 I0| 5 a 1 1 |0|0| 1 1 7 3 |0| 1 |0| 1 6 3 1 1 1 |0|0| t 8 4 1 |0| o| 1 1 7 " 1 |0| 1 lOjOl 5 10 0| |0| 8 |0| |0| 1 1 1 6 |0|0| |0|0| 9 13 8 6 4 2 5 7 No. 17.— Genoa Velvet. 6 4 2 3 1 5 No. 18.- —Plain Velvet. ■ 1 1 I'M 1 MM 1 1 1 1 III 1 " 1 |010|0| 1 I 2 1 1 III 2 " loiol 1 1 1 1 3 III 3 1 1 |0|0| 1 1 4 III * 1 |0| |0| i 1 5 1 1 1 1 5 1 I0| |0| 1 1 6 1 1 6 2 4 8 12 3 1 ft 7 5 10 11 9 1 3 7 5 4 2 8 After the fustian cloth is taken from the loom-beam, it is carried to the cutter, who nps up the surface-threads of weft, and produces thereby a hairy-looking stuff. FUSTIC. 837 Preparatory to its being cut, the cloth is spread evenly upon a table about six feet long, upon each end of which a roller mounted with a ralchet- wheel is fixed; the one to ^ive off, and the other to wind up the piece, in the above six-feet lengths. The knife is a steel rod about two feet long, and three eighths of an inch square, hay- ing a square handle at the one end ; the other end is laperwl away to a blade, as thin as paper. To prevent this point from turning downwards and injuring the cloth, its under side is covered by a guide which serves to stiffen it, as well as to prsvent its lower edge from cutting the fustian. The operative (male or female) grasps the handle in the right hand, and insinuating the projecting point of the guide under the weft, pushes the knife smaitly forward through the whole length of six feet, with a certain dexterous movement of the shoulder and right side, balancing the body meanwhile, like a fencer, upon the left foot. This process is repeated upon every adhesive line of the weft. The next process to which fustians are exposed is steeping in hot water, to take out the dressing paste. They are then dried, reeled, and brushed by a machine, &c. From twenty to thirty pieces, each eighty yards long, may be brushed in an hour. The breadth of the cloth is twenty inches. The maceration is performed by immersing the bundled pieces in tanks of water, heated by waste steam ; and the washing by means of a reel or winch, kept revolving rapidly under the action of a stream of cold water, for an hour or longer. After being thus ripped up, it is taken to the brushing or teazling machine, to make it shasgy. This consists of a series of wooden rollers, turning freely upon iron axles, and covered with tin-plate, rough with the burs of punched holes; and blocks of wood, whose con- cave under surfaces are covered with card-cloth or card-brushes, and which are made to traverse backwards and forwards in the direction of the axes of the revolving rollers, during the passage of the cloth over them. After they are brushed in the machine, the goods are singed by passing their cut surface over a cylinder of iron, laid in a horizontal direction, and kept red hot by a flue. See Sing KING. They are now brushed again by the machine, and once more passed over the singeing surface. The brushing and singeing are repeated a third, or even occasionally a fourth lime, till the cord acquires a smooth polished appearance. The goods are next steeped, washed, and bleached, by immersion in solution of chloride of lime. They are then dyed by appropriate chemical means. After which they are padded (imbued by the padding machine of the calico printers) with a solution of glue, and passed over steam cylinders to stiffen them. Smooth fustians, when cropped or shorn before dyeing, are called moleskins; but when shorn afier being dyed, are called beaverleen : they are'both tweeled fabrics. Cantoon is a fustian wiih a fine cord visible upon the one side, and a satiny surface of yarns running at risht angles to the cords upon the other side. The satiny side is sometimes smoothed by singeing. The stuff is strong, and has a very fine aspect. Its price is one shilling and sixpence a yard. Common plain fustian, of a brown or drab color, with satin top, is sold as low as seven pence a yard. A fustian, with a small cord running in an oblique direction, has a very agreeable ap- pearance. It is called diagonal. Moleskin shorn, of a very strong texture^ and a drab dyed lint, is sold at 20d. per yard. The weight of 90 yards of the narrow velveteen, in the green or undressed state, is about 24 pounds. The goods made for the German, Italian, and Russian markets are lighter, on account of the peculiarity in the mode of levying the import duty in these countries. Velveteens as they come from the loom, are sold wholesale by weight, and average a price of 20rf. per pound. They are usually woven with yarns of Upland and Brazil cotton wool, spun together for the warp ; or, sometimes, New Orleans alone. The weft is usu- ally Upland, sometimes mixed with East India cotton wools. Trouser velveteens are woven 19 inches wide, if they are to be cut up; if not, they are woven 30 inches, and called beaverleen. Cutting or cropping fustians by hand is a very laborious and delicate operation. The invention of an improved apparatus for effecting the same end with automatic pre- cision and despatch, was therefore an object of no little interest to this peculiar manufac- ture oC Manchester. An ingenious machine, apparently well calculated for this purpose, was made the subject of a patent by Messrs. William Wells and George Scholefield, of Salford, in November, IK34. FUSTIC. (Bois jaune, Fr. ; Gelbholz, Germ.) The old fustic of the English dyer, as the article fustet is their yellow fustic. It is the wood of the Morus tinctoria. It is lisrht, not hard, and pale yellow with orange veins ; it contains two coloring matters, one resinous, and another soluble in water. The latter resembles weld, but it has more of an orange cast, and is not so lively. i 838 GALL-NUTS. Its decoctions in water are brightened by the addition of a little glue, and more by car died milk. This wood is rich in color, and imparts permanent dyes to woollen stuffs^ when aided by proper mordants. It unites well with the blue of the indigo vat, and Saxon blue, in producing green of various shades. Alum, tartar, and solution of tin, render its color more vivid ; sea salt and sulphate of iron deepen its hue. From 5 to 6 parts of old fustic are sufficient to give a lemon color 1o 16 parts of cloth. The color of weld is however purer and less inclining to orange ; but that of fustic is less affected by acids than any other yellow dye. This wood is often employed with sulphate of iron in producing olive and brownish tints, which agree well with its dull yellow. For the same reason it is much used for dark greens. GABRONITE is a yellowish stony substance, of a greasy lustre and spec. gr.=2-74 ; affording no water by calcination ; fusible at the blowpipe into an opaque glass ; soluble in muriatic acid ; solution affords hardly any precipitate by oxalate of ammonia. This mineral is distinguished by the large quantity of soda which it contains ; its constituents being— silica, 54; alumina, 24; soda, 17-25; magnesia, 1-5; oxyde of iron, 1*25; water, 2. It belongs to the species Nepheline. GADOLINITE, called also Yttrite and Ylterbite, is a mineral of a black, brownish, or yellowish color, granular, or compactly vitreous, and conchoidal fracture ; of spec, grav. 4-23 ; readily scratching glass ; fusible at the blowpipe into an opaque glass, some- times with intumescence. It affords, with acids, a solution that lets fall, with caustic soda, a precipitate partly re-soluble in carbonate of ammonia. It is remarkable for con- taining from 45 to 55 per cent, of the earth Yltria; its remaining constituents being sili- ca, 25-8 ; oxyde of cerium, 17-92; oxyde of iron, 11-43. This mineral is very rare, hav- ing been hitherto found only in the neighborhood of Fahlon and Ytterby, in Sweden; its peculiar constituent was discovered by Professor Gadolin. GALACTOMETER, or LACTOMETER, is an instrument to ascertain the quality of milk; an article often sophisticated in various ways. Fresh milk, rich in cream, has a less specific gravity than the same milk after it has been skimmed ; and milk diluted with water becomes proportionably lighter. Hence, when our purpose is to determine the quantity of^ cream, the galactometer may consist merely of a long graduated glass tube standing upright upon a sole. Having filled 100 measures with the recent milk, we shall see, by the measures of cream thrown up, its value in this respect. A delicate long- ranged glass hydrometer, graduated from 1-000 up to 1-060, affords the most convenient means of detecting the degree of watery dilution, provided the absence of thickening ma- terials has been previously ascertained by filtration. Good fresh milk indicates from 1*030 to 1-032; when the cream is removed, 1-035 to 1-037. When its density is less than 1028, we may infer it has been thinned with water. GALBANUM is a gum-resin, which occurs sometimes in yellow, shining tears, easily agglutinated ; of a strong durable smell ; an acrid and bitter taste; at other times in lumps. It exudes either spontaneously or from incisions made into the stem oClhe bubon galbanum, a plant of the family of umbelliferaf which grows in Africa, particularly in Ethiopia. It contains 67 of resin; 19-3 of gum; 6-4 of volatile oil and water; 7-5 of woody fibres and other impurities ; with traces of acid malate of lime. GALENA, {Plomb sulfure.Yt. ; BUiglam, Germ. ;) is a metallic looking substance of a lead-gray color, which crystaUizes in the cubical system, and is susceptible of cleavages parallel to the faces of the cube ; spec. gr. 7-7592 ; cannot be cut ; fusible at the blow- pipe with exhalation of sulphureous vapors ; is easily reduced to metallic lead. Nitric acid first dissolves it, and then throws down sulphate of lead in a white precipitate; the solution affording, wiih plates of zinc, brilliant laminae of lead (arbor Saturni.) It con- sists of sulphur, 13 ; lead, 85 ; with a little iron, and sometimes a minute quantity of silver. This is the richest ore of lead, and it occurs in almost every geological formation, in veins, in masses, or in beds. It is almost always accompanied by sulphuret of zinc, dif- ferent salts of lead, heavy spar, fluor spar, &c. Galena in powder, called Alquifoux, is employed as a glaze for coarse stoneware. GALIPOT is a name of a white semi-solid viscid rosin found on fir-trees ; or an infe- rior sort of turpentine, poor in oil. GALLATES ; salts consisting of gallic acid combined with bases ; the most important being that with oxyde of iron, constituting a principal part of the black dye. GALLIC ACID is the peculiar acid extracted from gall-nuts; which see. GALLIPOLI OIL is a coarse olive oil, containing more or less mucilage ; imported from a seaport so named, of the province of Otranto, in the kingdom of Naples. GALL-NUTS, or GALLS, (Noix de Galle, Fr. ; Galldpfely Germ. ;) are excrescences found upon the leaves and leaf-stalks of a species of oak, called Qxurcus infecto- ria, which grows in the Levant. They are produced in consequence of the puncture of the female of the gall wasp (Cynips folii quercus), made in order to deposite her GALL-NUTS. 839 ' eggs ; round which the juice of the tree exudes, and dries in concentric portions. When the insect gets fully formed, it eats through the nut, and flies off. The Levant galls are of two different appearances and qualities; the first aie heayy compact, imperforated, the insect not having been sufficiently advanced to eat its way through the shell ; prickly on the surface ; of a blackish or bluish green hue ; about the size of a musket-ball. These are called blacky blue, or Aleppo galls. The second are light, spongy, pierced with one or more holes ; smooth upon the surface, of a pale grayish or reddish yellow color, generally larger than the first, and are called white galls. Be- sides the galls of the Levant, others come from Dalmatia, Illyria, Calabria, &.c. ; but they are of inferior quality, being found upon the Quercus Cerris ; they are smaller, of a brown- ish color, and of inferior value. The further south the galls are grown, they are reckoned the better. Galls consist principally of three substances; tannin or tannic acid; yellow extractive; and gallic acid. Their decoction has a very astringent and unpleasant bitter taste. The following are their habitudes with various reagents : — Litmus paper is powerfully reddened. Stannous chloride (protomuriate of tin) produces an Isabel yellow precipitate. Alum ; a yellowish gray precipitate. Acetate of lead ; a thick yellowish white precipitate. Acetate of copper ; a chocolate brown precipitate. Ferric sulphate (red sulphate of iron) ; a blue precipitate. Sulphuric acid ; a dirty yellowish precipitate. Acetic acid brightens the muddy decoction. The galls of the Quercus Cerris and common oak (Galles a Vepine, Fr. ; Knopper%f Germ.) are of a dark brown color, prickly on the surface, and irregular in shape and size. They are used chiefly for tanning in Hungary, Dalmatia, and the southern provinces of the Austrian states, where they abound. Tannin or tannic acid is prepared as follows : Into a long narrow glass adopter tube, shut at its lower orifice with a cotton wick, a quantity of pounded galls are put, and slightly pressed down. The tapering end of the tube being inserted into a matrass or bottle, the vacant upper half of the tube is filled with sulphuric ether, and then closed with a ground-glass stopper. Next day there will be found in the bottle a liquid in two dis- tinct strata; of which the more limpid occupies the upper part, and the other, of a sirupy consistence and amber color, the lower. More ether must be filtered through the galls, till the thicker liquid ceases to augment. Both are now poured into a funnel, closed with the finger, and after the dense liquor is setlled at the bottom, it is steadily run off" into a capsule. This, after being washed repeatedly with ether, is to be transferred into a stove chamber, or placed under the receiver of an air pump, to be evaporated. The residuary aiatter swells up in a spongy crystalline form of considerable brilliancy, sometimes color- less, but more frequently of a faintly yellowish hue. This is pure tannin, which exists in galls to the amount of from 40 to 45 per cent. It is indispensable that the ether employed in the preceding process be previously agitated with water, or that it contain some water, because by using anhydrous ether, not a parti- cle of tannin will be obtained. Tannic acid is a while or yellowish solid, inodorous, extremely astringent, very soluble In water and alcohol, much less so in sulphuric ether, and uncrystallizable. Its watery solution, out of contact of air, undergoes no change; but if, in a very dilute state, *t be leii exposed to the atmosphere, it loses gradually its transparency, and lets fall a slightly grayish crystalline matter, consisting almost entirely of gallic acid. For procuring this acid in a perfectly pure state, it is merely necessary to treat that solution thus changed with animal charcoal, and to filter it, in a boiling state, through paper pre- viously washed with dilute muriatic acid. The gallic acid will fall down in crystals as the liquid cools. If the preceding experiment be made in a graduated glass tube containing oxygen over mercury, this gas will be absorbed, and a corresponding volume of carbonic acid gas will be disengaged. In this case the liquor will appear in the course of a few weeks as if traversed with numerous crystalline colorless needles of gallic acid. Tannin or tannic acid consists of carbon 51-56 ; hydrogen 4*20 ; oxygen 44-24. From the above facts it is obvious that gallic acid does not exist ready formed in gall- nuts, but that it is produced by the reaction of atmospheric oxygen upon the tannin of these concretions. Gallic acid is a solid, feebly acidulous and styptic to the taste^ inodorous, crystallizing in silky needles of the greatest whiteness ; soluble in about 100 times its weight of col<5 and in a much smaller quantity of boiling water ; more soluble in alcohol than in water, Out litUe so in sulphuric ether. Gallic acid does not decompose the salts of protoxyde of iron, but it forms, with the sulphate of the perotyde, a dark blue precipitate, much less insoluble than the tannate of iron. Gallic acid takes the oxyde from the acetate and nitrate of lead, and throws 840 GALL OF ANIMALS. down a white gallale unchangeable in the air, when it is mixed with that acetate and nitrate. It occasions no precipitate in solutions of gelatine (isinglass or glue), by which criteridn its fieedom from tannin is verified. Gallic acid occurs but seldom in nature ; and always united to brucine, veratrine, or lime. Its constituents are carbon 49-89 ; hydrogen 3*49 ; oxygen 46-62. Li the crystal- line state it conlains one atom of water, which it loses by drying. Scheele obtained gallic acid by infusing pounded galls for 3 or 4 days in 8 times their weisht of water, and exposing the infusion to the air, in a vessel covered loosely with paper. At the end of two inonihs, the liquor had almost all evaporated, leaving some mouldiness mixed with a crystalline precipitate. The former being removed, the de- posite was squeezed in a linen cloth, and then treated with boiling water. The solution, being gradually evaporated, yielded crystals of gallic acid, granular or star-like, of a grayish color. These crystals might be whitened by boiling their solution along with a little animal charcoal. About one fifth of gallic acid may be obtained by Scheele's pro- cess from good gall-nuts. From a decoction of 500 parts of galls. Sir H. Davy obtained 185 parts of solid extract ; which consisted of 130 parts of tannin ; 31 parts of gallic acid with extractive; 13 parts of mucilage; 12 parts of lime and salts. Hence gall-nuU would seem to contain, by this statement, more than two thirds of their weight of tannin. This result is now seen, from the above experiments of Pelouze, to have been incorrect, in consequence of the admixture of yellow extractive in Davy's tannin. The use of galls in many processes of dyeing, and in making black ink, is detailed under their respective heads. GALL OF ANIMALS, or OX-GALL, purification of . Painters in water colors, scourers of chithes, and many others, employ ox-gall or bile; but when it is not purified, it is apt to do harm from the greenness of its own lint. It becomes therefore an impor- tant object to clarify it, and to make it limpid and transparent like water. The following process has been given fur that purpose. Take the gall of newly killed oxen, and after having allowed it to settle for 12 or 15 hours in a basin, pour the supernatant liquor off the sediment into an evaporating dish of stone ware, and expose it to a boiling heat in a water bath, till it is somewhat thick. Then spread it upon a dish, and place it before a fire till it becomes nearly dry. In this state it may be kept for years in jelly pots cov- ered with paper, without undergoing any alteration. When it is to be used, a piece of it of the size of a pea is to be dissolved in a table spoonful of water. Another and probably a belter mode of purifying ox-gall is the following. To a pint of the gall boiled and skimmed, add one ounce of fine alum in powder, and leave the mixture on the fire till the alum be dissolved. When cooled, pour into a bottle, which is to be loosely corked. Now take a like quantity of gall, also boiled and skimmed, add an ounce of common salt to it, and dissolve with heat ; put it when cold into a bottle, which is likewise to be loosely corked. Either of these preparations may be kept for several years without their emitting a bad smell. After remaining three months, at a moderate temperature, they deposite a thick sediment, and become clearer, and fit for ordinary uses, but not for artists in water colors and miniatures, on account of their yellowish-green color. To obviate this inconvenience, each of the above liquors is to be decanted apart, after they have become perfectly settled, and the clear portion of both mixed together in equal parts. The yellow coloring matter still retained by the mix- lure coagulates immediately and precipitates, leaving the ox-gall perfectly purified and colorless^ If wished to be still finer, it may be passed through filtering paper; but it becomes clearer with age, and never acquires a disagreeable smell, nor loses any of its good qualities. Clarified ox-gall combines readily with coloring matters or pigments, and gives them solidity either by being mixed with or passed over them upon paper. It increases the brilliancy and the durability of ultramarine, carmine, green, and in general of all delicate colors, whilst it contributes to make them spread more evenly upon the paper, ivory, &c. When mixed with gum-arabic, it thickens the colors without communicating to them a disagreeable glistering appearance; it prevents the gum from cracking, and fixes the colors so well that others may be applied over them without degradation. Along with lamp black and gum, it forms a good imitation of China ink. When a coat of ox-gall is put upon drawings made with black lead or crayons, the lines can no longer be effaced^ but may be painted over safely with a variety of colors previously mixed up with the same ox-gall. Miniature painters find a great advantage in employing it; bypassing it over ivory, it removes completely the unctuous matter from its surface; and when ground with the colors, it makes them spread with the greatest ease, and renders them fast. It serves also for transparencies. It is first passed over the varnished or oiled paper, and is allowed to dry. The colors mixed with the gall are then applied, andcannol aAerwards be removed by any means. It is adaptedfinally for taking" out spots of grease and oil. GARNET. 841 GALL OF GLASS, called also sandiver, is the neutral salt skimmed off the surface of melted crown glass ; which, if allowed to remain too long, is apt to be reabsorbed in part, and to injure the quality of the metal, as the workmen call it. GALVANIZED IRON, is the somewhat fantastic name newly given in France to iron tinned by a peculiar patent process, whereby it resists the rusting influence of damp air, and even moisture, much longer than ordinary tin plate. The following is the pre* scribed process. Clean the surface of the iron perfectly by the joint action of diluto acid and friction, plunge it into a bath of melted zinc, covered with sal-ammoniac, and stir it about till it be alloyed superficially with this metal ; when the raetal thus pre- pared is exposed to humidity, the zinc is said to oxidise slowly by a galvanic action, and to protect the iron from rusting within it, whereby the outer surface remains for a long period perfectly white, in circumstances under which iron tinned in the usual way would have been superficially browned and corroded with rust. G A LVANO- PLASTIC is the German name of Electro-Metallurgy. GAMBOGE ; {Oomme Chttte, Fr. ; Ghitti, Germ.) is a gum resin, concreted in the air, from the milky juice which exudes from several trees. The gamhogia giUta, a tree which grows wild upon the coasts of Ceylon and Malabar, produces the coarsest kind of gam- boge ; the guttcefera vera {Stalagmites camhogioides) of Ceylon and Siam affords the best. It comes to us in cylindrical lumps, which are outwardly brown yellow, but reddish yellow within, as also in cakes ; it is opaque, easily reducible to |>owder of specific gravity 1-207, scentless, and nearly devoid of taste, but leaves an acrid feeling in the throat. Its powder and watery emulsion are yellow. It consists of 80 parts of a hyacinth red resin, soluble in alcohol; and 20 parts of gum; but by another analysis, of 89 of resin, and 105 of gum. Gamboge is used as a pigment, and in miniature painting, to tinge gold varnish ; in medicine as a powerful purge. It should never be employed by confectioners to colour their liqueurs, as they sometimes do. GANGUE. A word derived from the German ga7ig, a vein or channel. It signifies the mineral substance which either encloses or usually accompanies any metallic ore in the vein. Quartz, lamellar carbonate of lime, sulphate of baryta, sulphate and fluate of lime, generally form the gangues ; but a great many other substances become such when they predominate in a vein. In metallurgic works the first thing is to break the mixed ore into small pieces, in order to separate the valuable from the useless parts, by pro- cesses called stamping, picking, sorting. See Metallurgy and Mines. GARANCINE, is a dyeing substance prepared from madder, called in the French language garance. A patent was gianted in August, 1843, to Mr. F. Steiner, for the manufacture of Oarancitie from used madder, formerly thrown away, as being exhausted of its dyeing Erinciple. His process is as follows:— "A large filter is constructed outside the uilding in which the dye- vessels are situated, formed by sinking a hole in the ground, and lining it at the bottom and sides with bricks without any mortar to unite them. A quantity of stones or gravel is placed upon the bricks, and over the stones or gravel common wrappering, such as is used for sacks. Below the bricks is a drain to take off the water which passes through the filter. In a tub adjoining the filter is kept a quantity of dilute sulphuric acid, of about the specific gravity of 105, water being 100. Hydrochloric acid will answer the several purposes, but sulplmric acid is preferred n» more economical. A channel is made from the dye- vessels to the filter. The madder which has been employed in dyeing is run from the dye- vessels to the filter- and while it is so running, such a portion of the dilute sulphuric acid is run in and mixed with it as changes the colour of the solution and the undissolved madder to an orange tint or hue. This acid precipitates the colouring matter which is held in solution, and prevents the undissolved madder from fermenting or otherwise decomposino-. When the water has drained from the madder through the filter, the residuum is taken from off the filter and put into bags. The bags are then placed in an hydraulic press, to have as much water as possible expressed from their contents. In order to break the lumps which have been formed by compression, the madder or residuum is passed through a sieve. To 5 cwt. of madder in this state, placed in a wood or lead cistern, 1 cwt of sulphuric acid of commerce is sprinkled on the madder through a lead vessel similar in form to the ordinary watering-can used by gardeners. An instrument like a garden spade or rake is next used, to work the madder about, so as to mix it intimately with the acid. In this stage the madder is placed upon a perforated lead plate, which is fixed about five or six inches above the bottom of a vessel. Between this plate and the bottom of the vessel is introduced a current of steam by a pipe, so that it passes through the perforated plate and the madder which is upon it. During this process, which occupies from one to two hours, a substance is produced of a dark brown colour approaching to black. This substance is garancine and insoluble carbonized matter. Wijen cool, it is placed upon a filter and washed with clear cold water until the water S42 GAS. I If passes from it without an add taste. It is then put into hags and pressed with an n)»draulic press. The substance is dried in a stove and ground to a fine powder under ordinary madder stones, and afterwards passed through a sieve. In order to neutralize any acid that may remain, from 4 to 5 lbs. of dry carbonate of soda for every hundred weight of tliis substance is added and intimately mixed. The garancine in tliis state is ready {or use." GARNET {Grenat, Fr. ; Granat, Germ.); is a vitreous mineral of the cubic system, of which the predominating forms are the rhomboidal dodecahedron and the trapaezo- hedron ; specific gravity varying from 3-35 to 4-24 ; fusible at the blowpipe. Its con- stituents are, silica, 42 ; alumina, 200 ; lime, 340; protoxide of iron, 4. Garnets are usually disseminated, and occur in all the primitive strata from gneiss to clay slate. The finer varieties, noble garnet or Almandine, and the reddish varieties of Grossulaire (Essonite), are employed in jewelry ; the first are called the Syrian or oriental ; the others, hyacinth. In some parts of Germany garnets are so abundant as to be used as fluxes to some iron ores : in others, the garnet gravel is washed, pounded, and em- {)loyed as a substitute for emery. The garnets of Jfegu are most highly valued. Fac- titious garnets may be made by the following composition :— Purest while glass, 2 ounces ; glass of antimony, 1 ounce ; powder of cassius, 1 grain ; manganese, 1 grain. GAULTHERIA OIL; an aromatic oil, called in commerce wintergreen oil. It is obtained from a shrub of the Ericeen family, {Qaultheria procumbens L, Canadian tea.) The oil occurs in all parts of the plant, but mostly in the flowers, and may be extracted by alcohol, but not by water from the dried or scentless plant. The same oil is obtained from the bark of sweet birch, by distilling it with water, whereby it results from the mutual action of a body like emulsion upon a body like amygdalin. The oil is colourless, but becomes reddish in the air, as it is found in commerce. Its specific gravity is 1-173, and its boiling point 211° C. ; it distils at the constant heat of 220°; it has then a gravity 1-18: the watery solution of the oil produces with the red salts of iron a violet tint, which becomes with excess of oil very deep and rich. Its constituents are C„ = 1200 63-16 Ha = 100 5-26 O. = 600 31-58 1900 100-00 If we distil the oil with an excess of caustic potash, wood spirit comes over, and the renaainder consists of salicylate of potash. The oil is a natural compound wood ether, which may be prepared artificially by distilling together two parts of salicylic acid with two parts of dry wood spirit, and one part of oil of vitriol. The ether is separable from the distilled liquor by means of chlorcalcium. Bromine and chlorine act violently upon the oil. The gaultheria oil combines without decomposition into a peculiar class of salts. GAULTHERINE. When the pulverized dried bark of hetula lenta is exhausted with cold alcohol of 95°, it can afford no more oil The fluid which contains the gaultherine has a slight bitterish taste, and by evaporation it forms a dry gummy mass, which at a high heat leaves a coaly residual. Oil of vitriol dissolves the gaultherine with a red colour and a flavour of the oil. GAS (Eng. and Fr.; Gaz, Germ.) is the generic name of all those elastic fluids which are permanent under a considerable pressure, and at the temperature of zero of Fahren- heit. In many of them, however, by the joint influence of excessive cold and pressure, the repulsive stale of the particles may be balanced or subverted, so as to transform the elastic ^as into a liquid or a solid. For this most interesting discover}-, we are indebted to the fine genius of Mr. Faraday. The following table exhibits the temperatures and pressures at which certain gases are liquefied. Name of the gas. Becomen liquid Calculated boiling point ; fiaroni. = 30 inches. At Under a pressure of Sulphurous acid Chlorine Ammonia _ - - Sulphureted hydrogen - Carbonic acid - - - Hydrochloric or muriatic acid - Deutoxide of azote 59° F. 60 50 50 32 50 45 3 atmospheres. 4 6-5 17 36 50 50 — 4° Fahr. -• 22 — 64 — 142 — 229 — 249 ~ 254 GAS-LIGHT. 843 ) i Liquid carbonic acid becomes solidified, into a snowy-looking substance, by its own rapid evaporation. Oxygen, hydrogen, and azote, have hitherto resisted all attempts to divest them of their elastic form. For this purpose, it is probable that a condensing force equal to that of 650 atmospheres, will be required. The volume of aoy gas is, generally speaking, inversely as the pressure to which it is exposed ; thus, under a double pressure its bulk becomes one half; under a triple pres- sure, one third ; and so on. For the change of volume in gaseous bodies by heat, see Expansion. Ammonia, carbonic acid, carbureted hydrogen, chlorine, muriatic acid, sulphurous acid, sulphureted hydrogen, are the gases of most direct interest in the arts aoH manu* factures. Their detailed examination belongs to a work on chemistry. GAS-LIGHT. (Eclairage par gas, Fr. ; GasHcht, Germ.) Dr. Clayton iemon- strated, by numerous experiments in 1737 and 1738, that bituminous pit-coal subjected to a red heat in close vessels, afforded a great deal of an air simJar to the fire-damp of mines, but which burned with a brighter flame. It does not appear that this species of factitious air was ever produced from pit-coal for the purpose of artificial illumination till 1792, when Mr. William Murdoch, engineer to Messrs. Bolton and Walt, employed ^^al gas for lighting his house and offices, at Redruth in Cornwall. The gas was gen- erated in an iron retort, whence it was received in a gasometer, distributed in diflfer- ent situations by pipes, and finally burned at small apertures which could be opened and stopped at pleasure. He moreover made this light moveable, by confining the gas in portable tin-plate vessels, and burning it wherever he pleased. Between this period and 1802, Mr. Murdoch continued at intervals to make similar experimer.ts ; and upon occasion of the national illumination in the spring of the latter year, at the peace of Amiens, he lighted up part of the Soho manufactory with a public display of gas- lights. The earliest application of this artificial light, on a large systematic scale, was made at Manchester ; where an apparatus for lighting the great cotton mills of Messrs. Philips and Lee, was fitted up in 1804 and 1805, under the direction of Mr. Murdoch. A quantity of light, nearly equal to 3000 candles, was produced and distributed in this building. This splendid pattern has been since followed very generally in Great Britain, and more or less in many parts of the continents of Europe and America. By the yeai 1822, 8:as-lighting in London had become the business of many public companies. At the Peter street station, for example, 300 retorts had been erected, supplying 15 gasome- ters, having each an average capacity of 20-626 cubic feet, but, being never quite filled, their total contents in gas might be estimated at 309,385 cubic feet. The extent of main pipes of distribution belonging to this station was then about 57 miles, with two separate mains in some of the streets. The product of gas was from 10,000 to 12,000 cubic feet from a chaldron of coals. The annual consumption of coals was therefore altogether 9282 chaldrons, aff'ording 11,384,000 cubic feet of gas, allowing 153 retorts to be in constant daily action, upon an average of the year; and illuminating 10,660 private lamps, 2248 street lamps, and 3894 theatre lamps. At the Brick-lane works, 371 retorts were fixed in 1822, 133 being worked on an aver age of summer and winter. There were 12 gasometers, charged with an average quantity of gas amounting to 197,214 cubic feet. Of coals, 8060 chaldrons were annually con- sumed ; 96,720,000 cubic feet of gas were generated ; for the supply of 1978 public lamps, and 7366 private ones, connected with main pipes 40 miles long. At the Curtain-road gas establishment, there were 240 retorts ; but the greatest number worked in 1821 was only 80, and the lowest 21. The six gasometers had an average contents of 90,467 cubic feet. Of coals, 3336 chaldrons were annually consumed, yield- ing 40,040,000 cubic feet of gas, that supplied 3860 private lamps, and 629 public ones, by means of mains 25 miles long. The above three stations belonged to the London Gas- Lisht and Coke Company. The City of London Gas-Light Company, Dorset street, had built up 230 retorts, and 6 gasometers, while two were preparing; having a total capacity of 181,282 cubic feet. Of private lamps 5423 were lighted, and 2413 public ones, from mains extending 50 miles. The quantify of coals carbonized amounted to 8840 chaldrons ; producing 106,080,000 cubic feet of eas. The South London Gas-Light and Coke Company had mounted at Bankside 143 retorts, with 3 gasometers; the contents of the whole being 41,110 cubic feet, connected with mains from 30 to 40 miles long. At their other station, in Wellington street, 9 large gasometers were then erecting, with a capacity of 73,565 cubic feet, which were to be supplied with gas from Bankside, till retorts were mounted for them. The Imperial Gas-Light and Coke Company had at that lime 6 gasometers in progresi at their Hackney station. In 1822 there were thus four great companies, having in all 47 gasometers at work, capable of containing 917,940 cubic feet of gas, supplied by 1315 retorts, which generated 844 GAS-LIGHT. Tlfis"'!^ "'"''^^''''.'^P^^'^^^'T'f '^/"^^"^S^^^'^y ^^»*=^ «''203 private lan,|»,and 7268 public or street lamps, were huhted in the metropolis. Besides these publircom- panies, tliere were likewise several private ones. 1. Of the genera/iou of illuminating gam.— Pure hydrogen gas bums with too feeble a flame lo be employed lor illumination. But carbureted hydrogen having the property of prec.p.tat.ng its carbon in the act of burning, its solid particles become incandescenL and diiiuse a v.vid light. The more carbon it contains, the more brightly does it burn. This gas exists in two distinct stales of combination. In the first, two measures of hy- drosen gas are combined with one measure of the vapor of carbon, forming together one TnTJ^ !''^ specific gravity is of course the sum of the weights of the constituents, ?. lo J f "",^f»»^^^'-'f ^ a/ being 1000. This is the gas which is found in mines, and L. r h J '" '^'"^^' ^'''"' .decomposing vegetable matter. In the second, two meas- ures ol hydrogen gas are combined with two of gaseous carbon, forming also one volume or measure whose weight or specific gravity is 0-985. This was at one time called the ?r .n»v iJ^^'n "T"'^ 'n^^?l °''''^^ "^'^^ ^*^'°''"^ *" «^'y ^o«^'"« compound was produced. It may be called as well oil gas, because it is generated in considerable quantities by the trnn: irT^'^K*" °^r^"- '^^'"^ '^^ "'^^^"^ ?^^ ^«»^*'"^ •» ^h« same volume double ablv br^" ; erl/r^I Th '°"'"'^" carbureted hydrogen, and it burns with a proportion- ably brighter flame. The gaseous oxyde of carbon, as well as sulphureted hydro-en gas burns with a feeb e blue light, but the latter produces in combustion su phuroUs add,^an oflensive and noxious gas. ^ ' origin '^i: ^^'^"'^^•^" ^^ carbonization in close vessels, all bodies of vegetable and animal ZSnot L^ut!.^ carbureted hydrogen gas; even charcoal, when placed in ignition in carT,?p.pH hv] ' ^y '^^^^'^P^S'"? the water, produces abundance of carbonic acid, Zh Zy* T' ^y?-"*?^"' '^"^ ^^^••^"^c «^yde. After separating the carbrmic acid ThlrlTl k' ' ""'""'i gas contains in 100 measures, 20 of carbureted hydrogen ; arp nZ^i -^ '^ ^u'^ substances for furnishing a gas rich in luminiferous materials are p tcoal, especia ly the cannel coal, resin, oU, fats of all kinds, tar, wax, &c. In some cases the gases evolved during the igneous decomposition of bones and other animal mat- ipt to emk aTtid oZ. ^'"°''"''' "^^ ^' '""^^"^'^ ^"' ^'"'"""^ ^'^^'^' ^"' '^'^ ^^^^ is ^'I^.nowf f' ^'^'ilV T.^''"'''' '^^u'^ ^° ^^"'^'°"' ^^^ P''^?''^^^ «^ decomposition IS as lo lows. First and before the retort becomes red hot, steam issues along with the atmospheric air. When the retort begins to redden, tar distils in consi.lerable quantity with some combustible gas, of which hydrogen mixed with ammoniacal gas forms a part. The evolution of gas increases as the retort becomes hotter, with a continual production nnif « wl^^h^Jr"'^'' i'quoras well as sulphurous acid from the pyrites of the coal, which unites with the ammonia. When the retort has come to a bright cherry red heat the eTntZrclli "-.- --t -tlve. By and by the gaseous product!:>7Jiminishi\'nd eventually ceases entirely, although the heat be increased. In the retort a quantity of carbonized coal or coke .emains while tar is found at the bottom of the receiver, covered phureted rdTori!""^ '*""'"' combined with carbonic and sulphurous acids, and sul. ^PvLI"'!"' ^h's^«sti»ation, the combustible gas be collected and examined at the That lb cTL '^T^.T' V.' ^"""^ '? '^''^'' '""'''"^'^y ^'^ ''' ^"'"iniferous powers. Iha which comes ofl before the retort has acquired its proper temperature gives a %tlf\: r^ ''^"^'1,"' '^' gas obtained by the ignition of m'oist chaCrcons s fng red heat is'thT"; 7^u' ''°^''^ ^'t" '^' T'' ^^' ^"^^ «^^"'^^^' throughout a vivid Frnm tn 1 , ^"^'^ ""^ ^"' *^«"«'^t'"^ "^^'^^V ^^ bi-carburctcd hydrogen or olefiant gas. : K ^?Au''f' '^ consists, for example, in 100 measures, of 13 of olefiant gas, 82-5 of TrtlT'^ A^i^T?' ^'^ .^^••bonic oxyde, 1-3 azote; the mixture having a specmi gravity of K .i K 'f''' P^'"'"'^' «s after 5 hours, it contains 7 measures of olefiant gas, 56 of carbureted hydrogen, 11 of carbonic oxyde, 21-3 of hydrogen, 47 of azote; the tn'ec^ fie gravity of the whole being 0-500. Towards the end of the%peration, as aft;r 10 hour , ,t contains twenty measures of carbureted hydrogen, 10 of carbonic oxyde, 60 of hydros gen 10 of azote with a specific gravity of only 0-345. The hydrogen becomes sulphur- eted hydrogen, if there be much pyrilous matter in the coal. The larger proportion of ^l T '''^\r-.^^'t "!: '5' ^■"'^ ^*^"''' ^'"^""lin? to about one fiAh of the whole ; in the three fulluw.ng hours the disengagement is tolerably uniform, constituting in all fifty- ""hltedtiis!" ^'^ ^"^' »^-r,aisone tenth; in the seyenth and efghth hour^s, From these observations are derived the rules for the production of a good light gas ZlTt": I^"^ '^?'''''^'' Ik' t'*""^r ^^""^^ ^«™^^"^« ^ith a retort preiiou^sly heaed loa cherry red, since thereby good gas is immediately produced, and a portioj Sine. •/' !i''*.T''''u^'^ '"l"" gas instead of being simply distilled over into the con- frn T^ r « K ^ K ^^^^ u^'^I'J** ^^ u^^^^'^y continued during the whole opeiation, trom 6 lo 8 hours; that it should not be increased, especially towards the end, for feax GAS-LIGHT. 845 of generating carbonic ox/de and hydrogen gases, as well as of injuring the retort when the cooling agency of gaseficaiion has become feeble; and that the operation should be stopped some time before gas ceases to come over, lest gases with feeble illuminating power should impoverish the contents of the gasometer. Upon the average, a pound of good coai atfords four cubic feet of gas, or a chaldion=26 cwts. London measure, jifTords from 12,000 lo 15,000 cubic feet, according to the form of the retort, and the manner of firing it. When oil, fats, rosin, tar, &c. are employed for the production of a light gas, it is not sufficient to introduce these substances into the retorts, and to heat them, as is done with coals. In this case, the greater part of them would distil over in the state of vola- tile oils, and very little gas be generated, only as much as corresponded to the quantity of fat, &.C. in. immediate contact wit^ the retort. It becomes therefore necessary to fill the retorts with pieces of brick or coke ; and to keep them in ignition, while the oil, &c. is slowly introduced into their interior. The fats instantly assume the vaporous stale, and thus coming into contact upon an extensive surface with Ihe ignited bricks, are decomposed into combustible gases. A small portion of carbonaceous matter re- mains in the retort, while much olefiant gas is formed, possessing a superior illumi- nating power lo common coal gas, and entirely free from sulphureous impregnation. The best oil gas is generated at a dull red, a heal much below what is requisite for the decomposition of coal. A more intense heat would indeed produce a greater volume of gas, but of a poorer quality, because the olefiant gas thereby deposites one half of its carbon, and is converted into common carbureted hydrogen. Oil affords at a lively red heat, gases which contain in 100 measures, 19 of olefiant gas, 32-4 of carbureted hydrogen, 122 of carbonic oxyde gas, 32-4 of hydrogen, and 4 of azote; the mean specific gravity being only 0-590. At a more moderate temperature it yields 22-5 of the olefiant, 50-3 carbureted hydrogen, 15-5 carbonic oxyde, 7-7 hydrogen, and 4 azote, with a specific gravity of 0*758. It contains when generated by dull ignition, as is usual in works on the manufacturing scale, in 100 parts from 38 to 40 of olefiant gas, and besides the carbureted hydrogen, a few per cent, of carbonic oxyde and azote, with a specific gravity of 0-900, and even upwards. One pound of oil or fluid fat aflfords 15 cubic feet of gas ; of tar afibrds about 12 cubic feet ; of rosin or pitch, 10 cubic feet. When the oil gas is compressed by a force of from 15 to 20 atmospheres, as was the practice of the Portable Gas Company, about one fifth of the volume of the gas becomes liquefied into an oily, very volatile fluid, having the specific gravity 0-821. It is a mixture of three fluids (consisting of carbureted hydrogen), of different degrees of volatility. The most volatile of these boils even under 32" F. Some of the vapor of this gas-oil is mixed with the olefiant gas in the general products of decomposition; in consequence of which they are sometimes richer in carbon than even olefiant gas, and have a higher illuminating power. Oil gas contains about 22 per cent, and coal gas about 3 J per cent, of this oily vapor. In the estimations of the composition of the gases given above, this vapor is included under olefiant gas. This vapor combines readily with sulphuric acid, and is thus precipitated from the gaseous mixture. The amount of olefiant gas is shown, by adding to the gas, contained over water, one half of its volume of chlorine, which, in the course of an hour or two, condenses the olefiant gas into an oily looking liquid (chloride of hydrocarbon.) After the mixture, the gases must be screened from the light, otherwise the common carbureted hydrogen would also combine with the chlorine, while water and carbonic acid would make their appearance. The oil employed for aflfdrding gas is the crudest and cheapest that can be bought ; even the blubber and sediment of whale oil are employed with advantage. After all, however, coal is so much cheaper, and the gas produced from it is now so well purified, that oil and rosin are very little used in gas apparatus. Apparatus for Coal Gas. — Coal gas, as it issues from the retort, cannot be directly employed for illumination ; for it contains vapors of tar and coal oil, as also steam impregnated with the carbonate, sulphite, and hydrosulphuret of ammonia. These vapors would readily condense in the pipes through which the gas must be dis- tributed, and would produce obstructions ; they must therefore be so far removed by previous cooling, as to be liable to occasion no troublesome condensation at ordinary temperatures. The crude coal gas contains moreover sulphureted hydrogen, whose com- bustion for light would exhale an oflTensive sulphureous odor, that ought to be got rid of as much as possible. Carbonic acid and carbonic oxyde gases, generated at first from the decomposition of the steam by the ignited coal, enfeeble the illuminating power of the gas, and should be removed. The disengagement of gas in the retorls is never uniform, but varies with the degree of heal lo which they are exposed; for which reason the gas must be received in a gasometer, where it may experience uniform pres- sure, and be discharged uniformly into the pipes of distribution, in order to ensure a steady discharge of gas, and uniform intensity of light in the burners. A coal gas appa- ratus ought therefore to be so constructed as not only to generate the gas itself, but to fiUfil the above conditions. 846 GAS-LIGHT. 1/ ^f In^^. 669, such an apparatus is represented, where the various parts are shown coft mected with each other, in section. A is the furnace with its set of cylindrical or elliptical retorts, five in number. From each of these retorts, a tube b proceeds perpendicularly upwards, and then by a curvt or saddle-tube, it turns down wards, where it enters a long horizontal cylinder under b, shut at each end with a screw cap, and descends to beneath its middle, so as to dip about an inch into the water contained in it. From one end of this cylinder the tube d passes downward, to connect itself with a horizontal tube which enters into the tar pit or cistern c, by means of the verti cal branch/. This branch reach es to near the bottom of the cy- lindrical vessel, which sits on the sole of the tar cistern. From the other side of the vertical branch /, the main pipe proceeds to the condenser d, and thence by the pipe /, into the purifier e ; from which the gas is immediately transmitted by the pipe p into the gasometer f. The operation proceeds in the following way : — As soon as gas begins to be disengaged from the ignited retort, tar and ammoni- acal liquor are deposited in the cylindrical receiver b, and fill it up till the superfluity runs over by the piperf, the level being con- stantly preserved at the line shown in the figure. By the same tarry liquid, the orifices of the several pipes ft, issuing from the retorts, are closed ; whereby the gas in the pipe d has its com- munication cut off with the gas in the retorts. Hence if one of the retorts be opened and emp- tied, it remains shut oflTfrom the rest of the apparatus. This in- sulation of the several retorts is the function of the pipe under b, and therefore the recurved tubed must be dipped .ns far under the surface of the tarry liquid, as to be in equilibrio with the pressure of the gas upon the water in the purifier. The tube b is closed at top with a screw cap, which can be taken off at pleasure, to per- mit the interior to be cleansed. Both by the overflow from the receiver-pipe b,' and by subse- quent condensation in the tube i, tar and ammoniacal liquor collect prosressively in the cistern or pit under c, by which mingled liquids the lower orifice of the vertical tube/ is closed, 130 that the gas cannot escape into the empty space of this cistern. These liquids flow over the edges of the inner vessel when it is full, and may from time to lime be drawn oflT by the stopcock at the bottom of the cistern. Though the gas has, in its progress hitherto, deposited a good deal of its tarry and ammoniacal vapors, yet, in consequence of its high temperature, it still retains a con- siderable portion of them, which must be immediately abstracted, otherwise the tar GAS-LIGHT. 847 would pollute the lime in the vessel e, and interfere with its purification. On this ac count the gas should, at this period of the process, be cooled as much as possible, in order to condense these vapors, and to favor the action of the lime in the purifier e, upon the sulphureled hydrogen, which is more energetic the lower the temperature of the gas. The c(»al gas passes, therefore, from the tube / into the tube h of the condenser d, which is placed in an iron chest g filled with water, and it deiK>sites more tar and ammoniacal liquor in the under part of the cistern at t, I. When these liquids have risen to a certain level, they overflow into the tar-pii, as shown in the figure, to be drawn oflf by the stop- cock as occasion may require. The refrigerated gas is now conducted into the purifier e, which is filled with milk of lime, made by mixing one part of slaked lime with 25 parts of water. The gas, as it enters by the pipe /, depresses the water in the wide cylinder n, thence passes under the perforated disc in the under part of that cylinder, and rising up througli innumerable small holes is distributed throughout the lime liquid in the vessel m. By contact with the lime on this extended surface, the gas is stripped of its sulphureted hydrogen and carbonic acid, which are condensed into the hydro-sulphuret and carbonate of lime ; it now enters the gasometer f in a purified state, through the pipep t, and occupies the space q. The gasometer, pressing with a small unbalanced force over the counterweight «, expels it through the main u u, in communication with the pipes of distribution through the buildings or streets to be illuminated. The parts abode and f, of which this apparatus consists, are essential constituents of every good coal-gas work. Their construction rests upon peculiar principles, is sus- ceptible of certain modifications, and therefore deserves to be considered in detail. The Retorts. — These are generally made of cast iron, though they have occasionally been made of baked clay, like common earthenware retorts. The original form was a cylinder, which was changed to an ellipse, with the long axis in a horizontal direction, then into the shape of the letter d with the straight line undermost, and lastly into a semi-cylinder, with its horizontal diameter 22 inches, and its vertical varying from 9 to 12. The kidney form was at one time preferred, but it has been little used of late. The form of retort represented in Jig. 670 has been found to yield the largest quantity of good gas in the shortest time, and with the least quantity of firing. The length is 7|, and the transverse area, from one foot to a foot and a half square. The arrows show the direction of the flame and draught in this excellent bench of retorts, as mounted by Messrs. Barlow. The charge of coals is most conveniently introduced in a tray of sheet iron, made somewhat like a grocer's scoop, adapted to the size of the retort, which is pushed home to its further end, inverted so as to turn out the contents, and then immediately withdrawn. The duration of the process, or the time of completing a distillation, depends upon the nature of the coal and the form of the retort. With cylindrical retorts it cannot be finished in less than 6 hours, but with elliptical and semi-cylindrical retorts, it may be completed in 4 or 5 hours. If the dis- tillation be continued in the former for 8 hours, and in the latter for 6, gas will continue to be obtained, but during the latter period of the operation, of indiflerent quality. The Receiver. — If the furnace contains only 2 or 3 retorts, a simple cylindrical vessel Standing on the ground half filled with water, may serve as a receiver; into which the tube from the retort may be plunged. It should be provided with an overflow pipe for the tar and ammoniacal liquor. For a range of several retorts, a long horizontal cylinder is preferable, like that represented at b in Jig. 671. Its diameter is from 10 to 15 inches. This cylinder may be so constructed as to separate the tar from the ammoniacal liquor, by means of a syphon attached to one of its ends. The Condenser. — The condenser, represented in Jig. 669, consists of a square chest g, made of wrought iron plates open at top, but having its bottom pierced with a row of holes, to receive a series of tubes. To these holes the upright four-inch tubes h h are secured by flanges and screws, and they are connected in pairs at top by the curved at saddle tubes. The said bottom forms the cover of the chest t, /, which is divided by ver tieal iron partitions, into half as many compartments as there are tubes. 848 GAS-LIGHT. GAS-LIGHT. 849 itt proceeding from one compartment lo another. These partition plates are left open at bottom, so as to place the liquids of each com- partment m communication. Thereby the gas passes up and down (he series of tubes, ♦ . . .u-_ rpjj^ condensed liquids descend into the box tj tj and flow over into the tar cistern, when they rise above ihe leve, /, /. The tar may be drawn off from time to time by the stopcock. Through the tube fr, cold water flows into the condenser chest, and the warm water passes away by a pipe at its upper edge. TiiC extent of surface which the gas requires for its refrigeration before it is admitted into the washing-lime ap- paratus, depends upon the tempera- ture of the milk of lime, and the quantity of gas generated in a certain time. It may be assumed as a determination sufliciently exact, that 10 square feet of surface of the condenser can cool a cubic foot of gas per minute to the temperature of the cooling water. For example, suppose a furnace or arch with 5 retorts of 150 pounds of . . _ - coal each, to produce in 5 hours 3000 cnbiic teet of gas, or 10 cubic feet per minute, there would be required, for the cooling surface of the condenser, 100 square feet = 10 X 10. Sui)pose 100,000 cubic feet ol gas to be produced m 24 hours, for which 8 or 9 such arches must be employed, the con- densmg surface must contain from 800 to 900 square feet. r/ie Pttn^er.— The apparatus represented in the preceding figure is composed of a cylindrical iron vessel, with an air- tieht cover screwed ^pon it, through which the cylinder n IS also fixed air-ti?ht. The bottom of this cylinder spreads out like the biim of a hat, Ibrming a horizontal circular partition, which is pierced with holes. Through a stuffing box, m the cover of this interior cylinder, the vertical axis of the agitator passes, which IS turned by wheel and pinion work, in order to stir up the lime from the bottom of the water in the purifier. The vessel o serves for introducing fresh milk of lin)e, as also for letting It oflT by a stopcock when it has become too foul for further use. The quantity of lime should be proportioned to the quantity of sulphureted hydrogen and carbonic acid contained in the gas. Supposing that in good coal gas there is 5 per cent, of these gases, about one pound and a half of lime will be requisite for every hun- dred cubic feet of coal gas generated, which amounts to nearly one sixteenth of the weight of coal subjected to decomposition. This quantity of lime mixed with the proper quantity of water will form about a cubic foot of milk of lime. Consequently, the capacity of the purifier, that is, of the interior space filled with liquid, may be taken at tour sevenths of a cubic foot for every hundred cubic feet of gas passing through it in one operation ; or for 175 cubic feet of gas, one cubic foot of liquor. After every operation, that is, afier every five or six hours, the purifier must be filled afresh. Sup- pose that m the course of one operation 20,000 cubic feet of gas pass through the „.,. «v u u , ,, 20,000 machine, this should be able to contain-jy3- = 1 14 cubic feet of milk of lime ; whence its diameter should be seven feet, and the height of the liquid three feet. If the capacity of «ie vessel be less, the lime milk must be more frequently changed. *n some of the large gas works of London the purifier has the following construction, whereby an uninterrupted influx and efflux of milk of lime takes place. Three single purifiers are so connected together, that the second vessel stands higher than the first, and the third than the second ; so that the discharge tube of the superior vessel, placed somewhat below Its coyer, enters into the upper part of the next lower vessel; conse- quently, should the milk of limo in the third and uppermost vessel rise above its ordi- nary level, it will flow over into the second/ and thence in the same way into the first; from which It is let off by the eduction pipe. A tube introduces the gas from the con- denser into the first vessel, another tube does the same thing for the second vessel, &c., and the tube of the third vessel conducts the gas into the gasometer. Into'lhe third vepsel, milk of lime is constantly made to flow from a cistern upon a higher level. By this arrangement, the gas passing through the several vessels in proportion as it IS purified, comes progressively into contact with purer milk of lime, whereby its purifi. cation becomes more complete. The agitator c, provided with two stirring paddles, if kept in continual rotation. The pressure which the gas has here to overcome is naturally three times as great as with a single purifier of like depth. Fig. 612 is a simple form of purifier, which has been found to answer well in practice. Through the cover of the vessel a b, the wide cylinder c d is inserted, having its lower end pierced with numerous holes. Concentric with that cy..nder is the narrower one s z, bound above with the flange a b, but open at top and bottom. The under edge g h of .this cylinder descends a few inches below the end c d of the outer one. About the middle "of the vessel the perforated shelf m n is placed. The shaft of the agitator /, passes through a stuffing box upon the top of the vessel. The gas-pipe g, proceeding from the condenser, enters through the flange a 6 in the outer cylinder, while the gas-pipe h goes from the cover to the gasometer. A stopcock upon the side, whose orifice of discharge is somewhat higher than the under edge of the outer cylinder, serves to draw off the milk of lime. As the gas enters through the pipe g into the space between the two cylinders, it displaces the liquor till it arrives at the holes in the under edge of the outer cylinder through which, as well as under the edge, it flows, and then passes up through the aper- tures of the shelf m n into the milk of lime chamber; the level of which is shown by the dotted line. The stirrer, /, should be turned by wheel w^ork, thou^'h it is here shown as put in motion by a winch handle. In order to judse of the degree of purity of the gas aftei its transmission through the lime machine, a slender syphon tube provided with a stopcock may have the one end inserted in its cover, and the other dipped into a vessel containing a solution of acetate of lead. Whenever the solution has been rendered turbid by the precipitation of sulpha- ret of lead, it should be renewed. The saturated and fetid milk of lime is evaporated in oblong cast-iron troughs placed in the ash-pit of the furnaces, and the dried lime is partly employed for luting the apparatus, and partly disposed of for a mortar or manure. By this purifier, and others of similar construction, the gas in the preceding parts of the apparatus, as in the retorts and the condenser, suffers a pressure equal to a column of water about two feet high ; and in the last described purifier even a greater pressure. This pressure is not disadvantageous, but is of use in two respects ; 1. it shows by a brisk jet of gas when the apparatus is not air-tight, and it prevents common air from entering into the retorts ; 2. this compression of the gas favors the condensation of the tar and ammoniacal liquor. The effect of such a degree of pressure in expanding the metal of the ignited retorts is quite inconsiderable, and may be neglected. Two contri- vances have, however, been proposed for taking off this pressure in the purifier. In fig. 673, m m are two similar vessels of a round or rectangular form, furnished at their upper border with a groove filled with water, into which the under edge of the cover fits, so as to make the vessel air-tight. The cover is suspended by a cord or chain which goes over a pulley, and may be raised or lowered at pleasure. The vessels them- selves have perforated bottoms, r r', covered with wetted moss or hay sprinkled over with slaked and sifted quicklime. The gas passes through the loosely compacted matter of the first vessel, by entering between its two bottoms, rises into the upper space / thence it proceeds to the second vessel, and, lastly, through the pipe tt, into the gasometer. 674 Th's method, however, requires twice as much lime as the former, without increasing the purity ol* the gas. The second method consists in compressing the gas by the ac- tion of an Archimedes screw, to such a degree, before it is admit- ted into the purifier, as that it may overcome the pressure of the column of water in that vessel. Fig. 674 exhibits this apparatus in section, d d is the Archimedes worm, the axis of which revolves at bottom upon the gudgeon e; it possesses a three-fold spiral, and is turned in the opposite direction to that in which it scoops the water. The cistern which contains it has an air-tight cover. The gas to be purified passes through the pipe c into the space d, over the water level d; the upper cells of the worm scoop in the gas at thU point, and I 850 GAS-LIGHT. carry it downwards, where it enters at g into the cavity e of a second cistern. In order thai the gas, after it escapes from the bottom of the worm, may not partially return throucrh /into the caon the other end of the chain there is a counterpoise, which takes off the greater pari of the weight of the gas-holder, leaving only so much as is requisite for the expulsion of the gas. The inner and outer surfaces of the gas-holder should be a few times rubbed over with hot tar, at a few days' interval between each application. The pulley must be made fast to a strong frame. If the water cistern be formed with masonry, the suspension of the gas-holder may be made in the following way. a a, fig. 676, is a hollow cylinder of casi iron, standing up through the middle of the gasometer, and which is provided at either end with another small hollow cylinder g, open at both ends and passing through the top, with its axis placed in the axis of the gas-holder. In the hollow cylinder G,the counterweight moves up and down, with its chain passing over the three pulleys b, b, b, as shown in fig. 676. E F are the gas pipes made fast to a vertical iron rod. Should the srasometer be* made to work without a counterweight, as we shall presently see, the central cylinder a a, serves as a vertical sruide. In proportion as the gas-holder sinks in the water of the cistern, it loses so much of Its weight, as is equal to the weight of the water displaced by the sides of the sinkin*' vessel; so that the gas-holder when entirely immersed, exercises the least pressure upon the gas, and when entirely out of the water, it exercises the greatest pressure. In order to counteract this inequality of pressure, which would occasion an unequal velocity in the efflux of the gas, and of course an unequal intensity of light in its flame, the weight of the chain upon which the gas-holder hangs is so adjusted as to be equal, throughout the length of its motion, to one half of the weight which the gas holder loses by immersion. In this case, the weight which it loses by sinking into the water, is replaced by the por- tion of the chain which, passing the pulley, and hanging over, balances so much of the ci.ain upon the side of the counterweight ; and the weight which it eains by risin? out of the water, is counterpoised by the links of the chain^ which, passing over the pulley, add to the amount of the counterweight. The pressure which the gas-holder exercises upon the gas, or that with which it forces it through the first mam pipe, is usually so reg- ulated as to sustain a column of from one to two inches of water; so that the water will staid in the cistern from one to two inches higher within, than without the gas-holder. The following computation will place these particulars in a clear light. Let the semi-diameter of the gas-holder, equal to the vertical extent of its motion into and out of the water, =Xi let the weight of a foot square of the side of the gas-holder, including that of the strengthening bars and ring, which remain plunged under the water, be = p ; then 652 aAS-LIGH'i. GAS-LIGHT. 853 1. the weight of the gas-holder in ita highest position = 3 p ir x«; 2. the wei-'ht of the sides of the gas-holder which play in the water = 2 p t xt; ^ 2 17 TT xS* S. the cubic contents of the immersed portion of the gas-holder = -—-— 112 ^^' 4. its loss of weight in water = —p^^fl. 5 the weight of the gas-holder in its lowest position = / 1 1 •> \ p V xi 13 — i_ \ 400 /~ 2-72pirx2; 56 6. the weight of n inches, height of water = "jg n n- x* ; 56n\ 7. the amount of the counterweight = n afi) 3 p — ^^ ) » 8. the weight of the chain for the length x = ^ p ^ ^^ If we reduce the weight of the gas-holder in its highest ^^^^ lowest positioi« to th heichTof a stratum of water equal to the surface of its top, this height is that of the column of water which would press the gas within the gasometer, were no counterweight employed ; it consists as follows : — 3p 9. for the highest position = — ; 2-72 p . 10. for the lowest =- For the case, «hen the height of the gas-holder is different from iU ,emi-diamet.r. let thi8 height U m X ; then the height of the water level y>- 11. for the highest position = p ^ 55 j » 4-t-l\72m\ 12. for the lowest = p{ — ^-g ) 13. the counterweight = 7rx2^p(l-i-2m)— _--j ; 112 J 4. the weight of the equalizing chains — j» ir m x2. • ^%iStfu^%ii?r;-rp:s^^^^^^^ in cubic feet will be IU,W/ ;, p - * P""' ' , . . ^pi^ht of the cha n for a length of When n = ^.^''-^^liTZ'^L^J^^^^^^ ^^« -"-^ ^^^^ The above estimate is made on the S'^PP^^^^^^" ?J.^^^/,^ ^vVnearW Uue with rega d to same specific gravity as the atmospherica air wh ch w^^^^^ J^^j^^„ oil gas under the ordinajr pressure, ^ut coal g«s whose specinc g >^^^J^ ^^.^^ on an average at about 0-5, exercises J^^^^y^^^yi^ftJe cub c foot of gas to be =0-0364 fouXthrcy^^^r^^^^^ ^--- '^ ^ "'ir ihe^weTghTif^^^^^^^^^ hfghrst'position = 3 p. x^im x,; ,/3p-?i^\-0-1143x2; 16. the counterweight = irx2ior jg / 112 ^ 01143x3 17. the weight of the chain for the length ^-^^P""' 2 ' 18 The height of the water pressure for the highest position, without the counter- ,, 3pir— 01143 X. weight =-i- — J „ „_ 2*72 p . * . * ^ m feel 56 19. the same for the lowest position = -^ The preceding values of p and x are, (16) = 3147; (17) = 203 ; (18) = 2-44 inches; (19) = 2-33 inches. J he water columns in the highest and lowest situations of the gas-holder here diflei about 01 of an inch, and this difJerenco becomes still less when p has a smaller value, lor example, 3 pounds, or when the diameter of ihe gas-holder is still greater. It would thus appear that for coal-gas gasometers, in which the height of the gas-holder does not exceed its semi-diameter, and especially when it has a considerable size, neither a compensation cham nor a counterweight is necessary. The only thing requisite, is to preserve the vertical motion of the gas-holder by a sufficient number of guide rods or pillars, placed either withm the water cisiern, or round about it. Should the pressure of the gas in the pipe proceeding from the gasometer, be less than in the -asomeler itself, this may be regulated by the main valve, or by water valves of various kinds. Or a small intermediate regulating gasometer may be introduced between the great gas-holder, and the main pipe of distribution. With a diameter of 61 feet in the gas-holder, the pressure jn the highest and lowest positions is the same. The gasometers employed in storing up gas until required for use, occupy, upon the old plan, much space, and are attended with considerable expense in erecting The water tank, whether sunk in the ground or raised, must be of equal dimensions with the gasometer, both in breadth and depth. The improved construction which we are about to describe, affords a means of reducing the depth of the tank, dispensing with the bridge of suspension, and of increasing at pleasure the capacity of the gasometer, upon a given base; thus rendering a small apparatus capable, if required, of holding a lar^'c quantity of gas, the first cost of which will be considerably less than even a small gi. ometer constructed upon the ordinary plan. Mr. Tait, of Mile-End Road, the inventor, has, we believe, been for some years connec ted with gas establishment s, and is therefore fully aware of the practical defects or advantages of the different constructions of gasometers now in use. Fig. t>l7 is a section of Mr. Tail's improved contrivance ; a a is the tank, occupied with water, 6 b two iron col- umns, with pulley-wheels on the top, c c, chains attached to a ring of iron, d rf, extend- ing round the gasometer, v.rhich chains pass over the pulley-wheels, and are loaded at their extremilies, for the purpose of balancing the weight of the mateiials of which the gasometer is composed. The gasometer is formed by 2 or 3 cylinders, sliding one within the other, like the tubes of a telescope ; t, g, c, is the first or outer cyl inder, closed at the top, and having the rinj^ of iron rf, passing round it, by which "the whole is suspended ; //, is the second cylinder, sliding freely within the first, and there may be a third -„. , . and fourth within these if necessary. When mere is no gas in the apparatus, all the cylinders are slidden down, and remain one withm the other immersed in the tank of water; but when the gas rises through the water pressing against the top of the gasometer, its buoyancy causes the cylinder c to as- cend. Round the lower edge of this cylinder a groove is formed by the turning in of the plate of iron and as it rises, the edge takes hold of the lop rimof ihe cylinder/, which is overlapped for that purpose. 'We groove at the bottom of the cylinder fills itself with water as 11 ascends, and by the rim of the second cylinder falling into it, an air-light hy- draulic joint is produced. s » "/ Thus several cylinders may be adapted to act in a small tank of water, by sliding one within the other, with lapped edges forming hydraulic joints, and by supporting the ap- paratus m the way shown, the centre of gravity will always be below the points of sus^ pension A gasometer may be made upon this plan of any diameter, as there will be no need of frame-work, or a bridge to support it ; and the increasing weight of the appara. tus as the cylinders are raised one after the other, may be counterpoised by loading tke ends of the chains c c. / s »"c The water in the gasometer need not be renewed; but merely so much of u as evaporates or leaks out, is to be replaced. Indeed, the surface of the water in the cistern gets covered with a stratum of coa oil, a few inches deep, which prevents its evaporation, and allows the gas to be saturated with this volatile substance, so as to increase its lUu- minating powers. The gasometer may be separated from the purifier by an intermediate vessel such Its IS represented Jig- 678, with which the two gas pipes are connected, a is the 854 GAS-LIGHT. GAS-LIGHT. I I cylindrical vessel of cast iron a, the end of the gas pipe which comes from the purifier immersed a few mchcs deep mto the liquid with which the vessel is about two thirds filled ; 6 is the gas-pipe which leads into the gasometer; c is a perpendicular tube, placed over the boiiom of the vessel, and reaching to within one third of the top, through which the liquid is introduced 678 into the vessel, and through which it escapes when it overflows the level d. In this tube the liquid stands towards the inner level higher, in propor- tion to the pressure of the gas in the gasometer. The fluid which is condensed in the gas-pipe b, and in its prolongation from the gasometer, runs off into the vessel a ; and therefore the latter must be laid so low that the said tube may have the requisite declivity. A straight stopcock may also be attached to the side over the bottom, to draw ofFany sediment. II. Application of Light-Gas. 1 Disirihulion of the pipes.— The pressure by which the motion of the gas is main- tained in \he pii^^^^ a certain height of water in the c stern of the gasom- eter From the SsiX^^^^ this pressure, and the quantity of gas wh.ch .n a g.ven Ume as an hourrmust be transmitted through a certain length of P'P^^' depends the wTdth or the d'ameter that they should have in order that the "^«^^-,-^y ^JJ^^^^Jfi^^^ by the friction which the gas, like all other fluids, experiences '^/"^f ' ^"f^.^j^^^^/, ^^^ sas might be prevented from issuing with the velocity required for he j els of flame^ The velocitv of the gas in the main pipe increases in the ratio of the squa.e root ol ine pr"cll of w^ter upon the gisLeter, and ^l-refore by increasm^^^^^^^^ the gas may be forced more rapidly along the remoter «"^ ,^'"^"f /^^"^ f^^*^^^^^^ nimi Thus it haonens however, that the gas will be discharged from the onhccs near f^gksom ter wth'r^^^ velocity., it is therefore .f-fjl^f .^^r^^yj,^ such a manne?, that in every point of their length the velocity of discharge maj be nearly the'^rsuTersTmovin^ralong the pipes, ^^fl^^l^Z^'^^^^^^^^^^^ .nitial velocity varies with the square root of flie length. The volume ol gas discnaigea from the enTof a P?pe^^^^ ^« '^'^ ^^"^'^ of its diameter, and m- v^ely as the sqLr^root of its length ; or, calling^the length l, the diameter r>, the cubic 855 feet of gas discharged in an hour k ; then k — VL Experience likewise shows, Iha for a pipe 250 feet long, which transmits in an hour 200 cubic feet of gas, one inch is a suflficient diameter. 1 D« __ Consequently, 200 : fc :: *• "Jf ? and D= V fe V l 144 1/250 VL -^^000" From this formula the following table of proportions is calculated. Number of cubic feet per hour. L 50 250 500 700 1000 1500 2000 2000 2000 2000 6000 6000 80(X) 8000 Length of pipe, in feet. Diameter, in inches These dimensions are applicable to the case where the body of gas is transmitted through pipes without being let off in its way by burners, that is, to the mains which conduct the gjs to the places where it is to be used. If the main sends off branches for burners, "lenlor the same length the diameter may be reduced, or for like diameter the lensth my be greater. For example, if a pipe of 5-32 inches, which transmits 2000 cubic feet through a length of 2000 feet, gives off, in this space, 1000 cubic feet of gas ; then the remamaer oi the pipe, having the same diameter, can continue to transmit the gas throtigh a length of 2450 feet = (^^??-^) 2 with undiminished pressure for the purposes of light- ing. Inversely, the diameter should be progressively reduced in proportion to the numb-r ol jets sent off m the length of ihe pipe. „.??''r!t' ^'^'' ^"^'\"^e' ^he gasometer to discharge 2000 cubic feet per hour, and the la it point of the jets to be at a distance of 4000 feet. Suppose also that from the gasomet .t Hi.^ , r^T ?^ ''^.^.^?-' ^^^ '^^^ proceeds through 1000 feet of close pipe, the diameter of the pipe will be here 4-47 inches; in the second 1000 feet of length, sup- fuL ,1'^.^ ° f '''^ ''^' ""^ ^^"^^ distances, 1000 cubic feet of gas, the diameter in this lens-th (calculated at 1500 cubic feet for 1000 feet long) = 3-87 inches- in the Jecko'nint"~n'o 'T Z'^/'?.^^^!^^ ^^f' "^ ^""^ ""^ ^^ ^'^'^ ««"> ^^ the diameler (reckoning /OO cubic feet for 1000 feet long) will be 2-65 inches; in the fourth and noh Tr^^"^^'^^ '"^'^^^.^^ ^" ^^«« ^''' '«"^> ^^^ P'I^« ^»-^ a'diameterof onlyan h.il7h ^ m' f ' ""Y-' '"^ P'^'^''^' * '^^-'"^^ ^^^^ ^""O" P'Pe is substituted ; this serted *" '°*'"'' '"^'' '^^''''^' ^'''"''^ P'^^' ^'^'^ ^^ conveniently in- The same relations hold with regard to branch pipes through which th- gas is trans- muted into buildings and other places to be illuminated. If^such pipes rrlke lUuent an^n lar turnings, whereby they retard the motion of the gas, they must be a third^or a Ht'tiTanTnc'hTrborr^ ^"^^"^^' '^''' of distribution ar/ never less than on^ nl«yi!!.?rr'"'*'".r^ ""^"V'^^ ^^' '^°'"^' * ^^'■y S^""^^^ quantity of light is required in panic ular localities, there ought to be placed near these spots gasometers of distribution which being filled durino: the slack hours of the day, are ready to supply the bu ne s a't ^i^ht' without makmg any considerable demand upon the original main pipe. Suppose he first mam be required to supply 8000 cubic feet in the hoar, for an ilium nation of 8 hours a the distance of 2000 feet, a pipe lOf inches in diamete'r would be necessary but if tVo iLZ" ^'"'.'''^T' °^ '''^^•^^^"tion, or station gasometer., be had recourse [0 into whilh fL^ I e cTtra J '""'^r^K' hours would flow through .he same distance conlinuousT; S of 8 Ono fRf^r^ V^l- ^"^"'^'y ""^"''"^ ^'' ^°"'" ^'-^^ *h^™ ^'^"'J be only one inches " '"'' ^''"^^"^"'Jy the diameter for such a pipe is only 6-15 All the principal as well as branch pipes, whose interior diameter exceeds an inch and ft ifiecTss^n ' Th^' '"" 'T V"" ' '''t ^^"='-"''' ^'^°^ ^^^^ <=-' - them wher' It IS necessary. These pipe lengths are shown in Jig. 679, havin- at one end a wid/- socket a, and at the other a nozzle 6, which fits the former. ' Afier^nserlin- the one i n the other m their proper horizontal position, a coil of hemp soaked with tar is driven home at the junction ; then a luting of clay is applied at the mouth, within which a rina of lead IS cast mto the socket, which is driven tight home with a m^lllt andllunt chi-? 679 E T TTriTr 'i' ^^i ^^ .. f „ linnnun,,,, 680 The pipes should be proved by a force nnmn hor«n« k • • j • iwo or three lengths of them should be io^nThr.^"" T^'^'f '"^^ ^'"^ ^^« ^«'''f»; be placed at least two feet I ow the suIZ^ to °'"' '»y'"§^ .^hem down, and they should of temperature, which would looTenthet^^^^^^^ TheTutl fo" ""?"' fvTi '^ ^^""^^ of small size, are made of lead, copper w ought Iron, o^^ a " ^-^"^>"tion, when 856 GAS-LIGHT Iflslrad of a stopcock for letting off the eas in regulated quantities from the gas- ometer, a pecu.iarly formed water or mercurial valve is usually employed. Fig. 680 shows the mode of construction for a water trap or lute, and is, in fact, merely a gas- ometer in miniature, c d e f is a square cast iron vessel, in the one side of which a pipe A is placed in communication with the gasometer, and m the other, one with the main b, The moveable cover or lid h g i k has a partition, i. M, in its middle. If this cover be raised by its counterweight, the gas can pass without impediment from a to b ; but if the ct.unterweisht be diminished so as to let the partition plate l m sink into the water, the communication of the two pipes is thereby interrupted. In this case the water-level stands in the compartment a so much lower than outside of it, and in the comparimeni B, as is equivalent to tlie pressure in the gasometer ; therefore the pipes a and b must project thus far above the water. In order to keep the water always at the same height, and to prevent it from flowing into the mouths of these pipes, the rim c D of the outer vessel stands somewhat lower than the orifices A b ; and thence the vessel may be kepi always full of water. If a quicksilver valve be preferred, it may be constructed as shown in Jig. 681. a b are the terminations of the two gas pipes, which are made fast in the rectangular iron vessel m. e is an iron vessel of the same form, which is filled with quicksilver up to the level a, and which, by means of the screw g, which presses aeainst its bottom, and works in the fixed female screw c c, may be moved up or down, so that the vessel M may be immersed more or less into the quicksilver. The vessel m is furnishet' with a vertical partition m ; the passage oi the gas from a to b is therefore obstructed when this partition dips into the quick- silver, and from the gradual depression of the vessel e by its screw, the interval be tween the quicksilver and the lower edge of the partition, through which the gag must enter, may be enlarged at pleasure, whereby the pressure of the gas in b may be regulated to any degree. The trans- verse section of that interval is equal to the area of the pipe or rather greater ; the breadth of the vessel m from a to b amounts to the double of that space, and its length to the mere diameter of a or b. The greatest height to which the partition m can rise out of the quicksilver, is also equal to the above diameter, and in this case the line a comes to the place of b. The vertical movement of the outer vessel e, is secured by a rectangular rim or hoop which surrounds it, and is made fast to the upper part of the vessel m, within which guide it moves up and down. Instead of the lever d d, an index with a graduated plate may be employed to turn the screw, and to indicate exactly the magnitude in the opening of the valve. In order to measure the quantity of iraa which passes through a pipe for lightitg a factory, theatre, &c., the gas-meter is em- ployed, of whose construction asitficientiy precise idea may be formed from the con- sideration oCJig. 682, which shows the in- strument in a section perpendicular to its axis. Within the cylindrical case a, there is a shorter cylinder b 6, shut at both ends, and moveable round an axis, which is divided into four compartments, that communicate by the opening d, with the interval between this cylinder and the outer case The mode in which this GAS-LIGHT. 867 cylinder turns round its axis is as follows :— The end of the tube c, which is made fast to the side of the case, and by which the gas enters, carries a pivot or gudgeon, upon which the centre of its prop turns ; the other end of the axis runs in the cover, which here forms the side of a superior open vessel, in which, upon the same axis, there is a toothed wheeL The vessel is so far filled with water, that the tube c just rises above it, which position is secured by the level of the side vessel. When the gas enters through the tube c, by its pressure upon the partition e (Jig. 682), it turns the cylinder from right to left upoB its axis, till the exterior opening d rises above the water, and the gas expands itself in the exterior space, whence it passes off through a lube at top. At every revolution, a certain volume of gas thus goes through the cylinder, proportional to its known capa- city. The wheel on the axis works in other toothed wheels, whence, by means of an index upon a graduated disc or dial, placed at the top or in front of the gas-meter, the number of cubic feet of gas, which pass through this apparatus in a given time, is registered. B. Employment of the gas for lighting. — The illuminating power of different gases burned in the same circumstances, is proportional, generally speaking, to their specific gravity, as this is to the quantity of carbon they hold in combination. The following table exhibits the different qualities of gases in respect to illumination. Density or specific gravity. Propoition of light afforded by coal gas to oil gas. Coal gas. Oil gas. 0-659 0-578 0-605 0-407 0-429 0-508 0-818 0-910 1-110 0-940 0-965 1-175 100 : 140 100 : 225 100 : 250 100 : 354 100 : 356 100 : 310 Mean 0.529 0-96 100 : 272 j In the last three proportions, the coal gas was produced from coals of middle quality ; in the first three proportions, from coals of good quality ; and therefore the middle pro- portion of 100 to 270 may be taken to represent the fair average upon the great scale. On comparing the gas from bad coals, with good oil gas, the proportion may become 100 to 300. Nay, coal gas of specific gravity 0-4, compared to oil gas of 1-1, gives the proportion of 1 to 4. A mould tallow candle, of 6 in the pound, burning for an hour, is equivalent to half a cubic foot of ordinary coal gas, and to four tenths of a foot o{ good gas. The flame of the best argand lamp of Carcel, in which a steady supply of oil is maintained by pump-work, consuming 42 grammes = 649 grains English in an hour, and equal in light to 9-38 such candles, is equivalent to 3-75~cubic feet of coal gas per hour. The sinumbra lamp, which consumes 50 grammes = 772 grains English, of oil per hour, and gives the light of 8 of the above candles, is equivalent to the light emitted by 3-2 cubic feet of coal gas burning for an hour. A common argand lamp, equal to 4 candles, which consumes 30 grammes = 463 grains English per hour, is represented by 1-6 cubic feet of gas burning during the same time. A common lamp, with a flat wick and glass chimney, whose light is equal to 1-13 tallow candles, and which consumes 11 grammes = 169-8 grains English per hour, is represented by 0*452 of a ^ubic foot of gas burning for the same time. Construction of ihe Burners. — The mode of burning the gas as it issues from the jets has a great influence upon the quantity and quality of its light. When carbureted hydrogen gas is transmitted through ignited porcelain tubes, it is partially decomposed with a precipitation of some of its carbon, while the resulting gas burns with a feebler flame. Coal gas, when kindled at a small orifice in a tube, undergoes a like decompo- sition and precipitation, its hydrogen, with a little of its carbon, bums whenever it comes into contact with the atmospherical air, with a bluish colored flame; but the carbonaceous part not being so accendible, takes fire only when mixed with more air ; therefore at a greater distance from the beak, and with a white light from the vivid ignition of its solid panicles. Upon this principle pure hydrogen gas may be made tc burn with a white instead of its usual blue flame, by dusting into it particles of lamp black, or by kindling it at the extremity of a tube containing finely pulverized zinc. The metallic particles become ignited, and impart their bright light to the pale blue flame. Even platinum wire and asbestos, when placed in the flame of hydrogen gas, serve to whiten it. Hence it has been concluded, that the intensity of light which a gas IS capable of affording is proportional to the quantity of solid particles which it I I 858 GAS-LIGHT GAS-LIGHT. 859 contains, and can precip.tate in the act of burninu. Carbonic oxyde g&s burns witl. thf feeblest light next It) hydrogen, because it deposiles no carbon in the act of burning Phosphureted hydrogen gives a brilliant light, because the phosphoric acid, into which its base is converted during the combustion, is a solid substance, capable of being ignited in the flame, defiant gas, as also the vapor of hydro-carbon oil, emits a more vivid light than common coal gas ; for the first is composed of two measures of hydrogen and two measures of the vapor of carbon condensed into one volume ; while the last contains only one measure of the vapor of carbon in the same bulk, and combined with the same proportion of hydrogen, defiant gas may therefore be ex- pected to evolve a double quantity of carbon in its flame, which should emit a double light. The illuminating power of the flame of coal gas is, on the contrary, impaired, when, by admixture with other species of gas which precipitate no carbon, its own ignited par- ticles are diflTused over a greater surface. This happens when it is mixed with hydrogen, carbonic oxyde, carbonic acid, and nitrogen gases, and the diminution of the light is pro- portional to the dilution of the coal gas. In like manner the illuminating power of coal gas is impaired, when it is consumed loo rapidly to allow time for the separation and ignition of its carbonaceous matter; it burns, in this case, without decomposition, and with a feeble blue flame. 1. This occurs when the light-gas is previously mixed with atmospherical air, because the combustion is thereby accelerated throughout the interior of the flame, so as to prevent the due separation of carbon. A large admixture of atmospherical air makes the flame entirely blue. 2.' When it issues, with considerable velocity, from a minute orifice, whereby the gas, by expansion, gets intimately mixed with a large proportion of atmos- pherical air. If the jet be vertical, the bottom part of the flame is blue, and the more so the less carbon is contained in the gas. The same thing may be observed in the flame of tallow, wax, or oil lights. The burning wick ads the part of a retort, in decom- posing the fatty matter. From ihe lower part of the wick tne gases and vapors of the fat issue with the greatest velocity, and are most freely mixed with the air ; while the gases disengaged from the upper part of the wick compose the interior of the flame, and being momentarily protected from the action of the atmosphere, acquire the proper high temperature for the deposition of carbon, which is then diflTused on the outec surface in an ignited slate, and causes its characteristic white light. Hence with coal gas, the light increases in a certain ratio with the size of the flame as it issues from a larger orifice, because the intermixture of air becomes proportionately less. 3. If by any means too great a draught be given to the flame, its light becomes feebler by the rapidity and com- pleteness with which the gras is burned, as when too tall a chimney is placed over an argand burner, see Jig. 683. Fig. 684, c, is a view of the upper plate, upon which the glass chimney 6 rests. The gas issues through the smaller openings of the inner ring, and forms a hollow cylindrical flame, upon the outside as well as the inside of which the atmospherical air acts. The illuminating power of this flame may be diminished at pleasure, according as more or less air is allowed to enter through the orifices beneath. With a very f (111 draught the light almost vanishes^ leaving only a dull blue flame of great heating power, like that of the blowpipe, corresponding to the perfect combustion of the gas without precipitation of its carbon. 4. On the other hand, too small a draught of air is equally prejudicial; not merely because a portion of the carbon thus escape? unconsumed in smoke, but also because the highest illuminating power of the flame is obtained only when the precipitated charcoal is heated to whiteness; a circumstance which requires a considerable draught of air. Hence the flame of dense oil gas, or of oil in a wick, burns with a yellow light without a chimney ; but when it is increased in "ntensity by a chimney draught, it burns with a brilliant white flame. From the consideration of the preceding facts, it is possible to give to coal gas ita highest illuminating power. The burners are either simple beaks perforated with a small round hole, or circles with a series of holes to form an argand flame, as shown in fig, 684, or two holes drilled obliquely, to make the flame cross, like a swallow's tail, oi with a slit constituting the sheet of flame called a bat's wing, like most of the lamps in ths streets of London. These burners are mounted with a stopcock for regulating the quantity of gas. The height of the flame, which with like pressure depends upon the size of the orifice, and with like orifice upon the amount of pressure, the latter being modified by the stop- cock, is, for simple jets in the open air, as follows : — 2 3 55-6 100 60-5 101-4 109 Length of Ihe flame Intensity of the light Volume of gas consumed - Light with equal consumption When the length exceeds five inches, nothing is gained in respect to light. For oil 100 4 5 6 inches. 150 197-8 247.4 126-3 143-7 182-2 131 150 IdO 686 eas the «iame statements will serve, only on account of its superior richness in carbon, i1 does not bear so long a flame without smoke. Thus: Length of the flame - 1 2 3 4 5 inches. Intensity of the light - 22 63-7 96-5 141 178 Gas consumed - - 331 78*5 90 1J8 153 Light with equal consumption 100 122 159 181 174 The diameter of the orifice for single jets, or for several jets from the same beak, is one twenly-eiahlh of an inch for coal gas, and one forty-fifth for oil gas. When several jets issue from the same burner, the light is improved by making all the flames unite into one. In this case the heat becomes greater, for the combined flame presents a smaller surface to be cooled, than the sum of the smaller flames. The advan- tage gained in this way may he in the ratio of 3 to 2, or 50 per cent. In an argand burner the distances of the orifices for coal gas should be from JJL to -^S- of an inch and for oil gas ^l^^. If the argand ring has 10 orifices, the diameter of the central open- ing should be = --i^ of an inch; if 25 orifices, it should be one inch for coal gas; but for oil gas with 10 orifices, the central opening should have a diameter of half an inch, and lor 20 orifices, one inch. The pin holes should be of equal size, otherwise the larger ones will cause smoke, as in an argand flame with an uneven wick. The glass chimney is not necessary to promote the combustion of an argand coal gas flame, but only to pre- vent It from flickering with the wind, and therefore it should be made so wide as to exercise liille or no influence upon the draught. A narrcw chimney is necessary merely to prevent smoke, when a very strong light with a profusion of gas is desired. ' Oil gas burned in an argand beak requires a draught chimney, like a common argand lamp,^on account of the large quantity of carbon to be consumed. The most suitable mode of regulating the degree of draught can be determined onlv by experiment, and the best construction hitherto ascertained is that represented in Jig. 685. Fig. 686 exhibits the view from above, of the rim or ring c, upon which the chimney 6 stands, and which surrounds the per- forated beak. The ring is made of open fretwork, to permit the free passage of air upwards to strike the outside of the flame. The thin annular dsic rf, Q 685 which is laid over its fellow disc c, in the bottom of the chimney-holder, being turned a little one way or other, will allow more or less air to pass through for promoting, more or less, the draught or ven- tilation. The draught in the central tube of the • burner may be regulated by the small disc e, whose diameter is somewhat smaller than that of the ring of the burner, and which, by turning the milled head/, of the screw, may be adjusted with the greatest nicety, so as to admit a greater or smaller body of air into the centre of the cylindrical flame. In mounting gas-lights, and in estimating beforehand their illuminating eflfects, we must keep in mind the optical proposition, that the quantity of light is inversely as the square of the distance from the luminous body, and we must distribute the burners accordingly. When, for example, a gas-light placed at a distaace of ten feet, is required for reading or writing to aflford the same light as a candle placed at a distance of twa feet; squaring each distance, we have 100-4; therefore 15.0 _ 25, shows us that 25 such lights will be necessary at the distance of 10 feet. Concerning portable gas-light, with the means of condensing it, and carrying it from the gas woiier hour to furnish the light of a candle. All light gas should be nsed therefore as soon as possible after it is properly purified. Economical consideration's. — The cost of gas-light depends upon so many local cir cumstances, that no estimate of it can be made of general application ; only a fev. f 860 GAS-LIGHT. leading points may be stated. The coals required for heating the retorts used to constitute one half of the quantity required for charging the retorts themselves. When five retorts are healed by one fire, the expenditure for fuel is only one third of that when each retort has a fire. The coke which remains in the retorts constitutes about 60 per cent, of the weight of the original coal ; but the volume is increased by the coking in the proportion of 100 to 75. When the coke is used for heating the retorts, about one half of the whole is required. If we estimate the coke by its comparative heating power, it represents 65 per cent, of the coals consumed. One hundred pounds of good coal yield in distillation 10 pounds of ammoniacal liquor, from which sulphate or muriate of ammonia may be made, by saturation with sulphuric or muriatic acid, and evaporation. The liquor con- tains likewise some cyanide of ammonia, which may be converted into Prussian blue by the addition of sulphate of iron, after saturation with muriatic acid. Two hundred pounds of coal afford about 17 pounds of tar. This contains in 100 pounds 26 pounds of coal oil, and 48 pounds of pitch. The tar is sometimes employed as a paint to preserve wood and walls from the influence of moisture, but its disagreeable smell limits its use. The coal oil, when rectified by distillation, is extensively employed for dissolving caoutchouc in making the varnish of waterproof cloth, and also for burning in a peculiar kind of lamps under the name of naptha. Oil of turpentine, however, is often sold and used for this purpose, by the same name. If the coal oil be mixed with its volume of water, and the mixture be made to boil in a kettle, the mingled vapors when passed through a perforated nozzle may be kindled, and employed as a powerful means of artificial heat. The water is not decomposed, but it serves by its vapor to expand the bulk of the volatile oil, and to make it thereby come into contact with a larger volume of atmospherical air, so as to burn without smoke, under a boiler or any other vessel. The pitch may be decomposed into a light-gas. The relative cost of light from coal gas and oil gas may be estimated as one to six at least. Rosin gas is cheaper than oil gas. See Rosin. I shall conclude this article with a summary of the comparative expense of different modes of illumination, and some statistical tables. One pound of tallow will last 40 hours in six mould candles burned in succession, and costs 8d. ; a gallon of oil, capable of affording the liirht of 15 candles, for 40 hour^, costs 5*. ; being therefore ^ of the price of mould candles, and J^- of the price of « (A ^ w ^^ ' *»m ..^ n *" ^ ' "2 ' .C '" -" i I !" -3 JZJS Cubic Feet. 1-22 •85 -825 11 -9 1-2 ■855 1-04 11 1-3 1-2 1 15 1-13 O a 3 Cubic Feet. 2704 1489 1536 2646 1164 3123 1644 2440 2575 4200 3521 3069 3092 -«i V « 95 >~ I- *- hn = -»- ?'l Gas atin lbs. lies. — CO >? =0 ,S "o P -z ^-=- s. d. L. s. d. 10 1 7 10 )4 11 8 12 3 10 1 6 5 10 11 8 9 1 8 1 8 13 2 8 19 6 7 6 19 3 9 1 17 9 10 1 15 4 10 1 10 8 10 1 10 11 s • 5-5 •of C3 _j * ® si M fc- — ^ O" v.. ■"■ oi CSV -2=3 8 = 5 u a ^ I" Percent:, L. $. d. 9 121 Hi 6i 6i 4 15 15 15 15 none allowed 1 4 7 13 lU 10 1 4 9 9 10 1 4 12 18 16 1 11 1 10 1 6 I 10 11 5? tea u a. •541 •539 -534 •462 •580 •420 •530 •466 -5-28 •424 •448 •419 t -412 * }^ ''"'.- *'^ ca»<'l«s are csliniHted to burn 5700 hoars, t The candles cost 3/. 2s. 6 oiB.v^^ t\a\wm\.\j Hf 1,110 UOT3 \fl assimilate to the Liverpool New Company in illuminating power. Memorandum.— It will not fail to be observed that in deducing the comparative value between candles and gas by these experiments, the single jet^and in every instance, ol course, it was the same) has been the medium. This, however, though decidedly the most correct way of making the comparative estimate of the illuminating power of the several gases, is highly disadvantageous in the economical comparison, inasmuch as cas burnt in a properly regulated argand burner, with its proper sized glass, air aperture, and sufficient number of holes, gives an advantage in favor of gas consumed in an argand, over a jet burner, of from 30 to 40 pur cent. At the same lime it must not be overlooked, that in many situations where great light is not required, it will be lound far more economical to adopt the use of sinsle je's, which, by means of swin<» brackets and light elegant shades, becoinne splendid substitutes for candles, in banking ^ establishments, offices, libraries, &c. &c. Note.— In Glasgow, Edinburgh, Dundee, Perlh, and the Scotch towns generally, the Parrot or Scotch Cannel coal is used ; in illumiaatmg power and specific gravity the gas produced i« equal lo that from the be?t J^s.-ription of Cannel coal in England The price per 1000 cubic feet ranges about 9.-., with from 5 to 30 per cent, off for dis^ cotmts, leaving the net price about 9s. to hi-, equal in the above table to 100 lbs of candles. Epitome of E.xperiments made in Gas prc^Iucc-: from different qualities of Coal and consumed in different kinds of Burners: ' Tried at the Sheffield Gas Light Company's Works, and laid before a Committee of the House of Commons. By Joseph Hedley, Esq. Ditfe 1835. May 8 9 9 8 9 9 Description of Burner. Species of Coal. > 1° Distance of Candle from Shadow. Gas consumed per Hour. ^0 Equal lo Mould T.-tllow Can- dles, 6 to the pound, 9 inches long each. Gas equal to 100 lbs. of Mould Candles. Cost of Gas at 8*. per 1000 cubic feet. §^ ^ a Sins^le Jet Ditto Ditto Arg'and ) 14 holes 1 Ditto Ditto Deep Pit Mortormley Cannel Deep Pit Moitormley Cannel •410 -450 •660 •410 -450 -660 Inches 75 74 61J 34 33 29 Cubic Feet. 1- •95 •7 3-3 3 1 2-6 Inches 4 4 4 3.1 3| Candles. 2-36 2-434 354 1153 12-24 1.5-85 Cubic Feet. 2415 2224 1127 1631 1443 935 L. s. d. 19 3§1 17 9i 9 13 Oi ' 11 6i 7 53J L. 3. d. 3 2 6 862 GAS-LIGHT. Copy of Experiments made at the Alliance Gas Company's Works in Dublin, during lh€ past year 1837. By Joseph Hedley, Esq. Results of experiments on the qualities of various coals for the production of gas; its value in illuminating power; produce of coke, and quality ; and other particulars impor- tant in gas-making : — 1st Experiment, Saturday, May 27, 1837.— Deane coal (Cumberland), 2 cwts. of 112 lbs. each (or 224 lbs.) produced 970 cubic feet of gas; 4 bushels of coke of middling quality ; specific gravity of the gas, 475. Consumed in a single-jet burner, flame 4 inches high, Ij^^lhs cubic feet per hour; distance from shadow 76 inches, or 2-3 mould candles. Average quantity of gas made from the charge (6 hours) 4-33 cubic feet per lb., or 9,700 cubic feet per ton of 20 cwts. Increase of coke over coal in measure, not quite 30 per cent. Loss in weight between coal, coke, and breize 56 lbs., converted into gas, tar, ammonia, &c. « 2d Experiment, May 28.— Carlisle coal (Blenkinsopp). 224 lbs. produced 1010 cubic feet of gas, 4 bushels cf coke of good quality though small; increase of coke over coal in measure not quite 30 per cent. Loss in weight, same as foregoing experiment. Average quantity of gas made from the charge (6 hours) 4-5 cubic feet per lb. or 10,080 per ton. Illuminating power of the Gas. i Consumed per hour, single jet. Distance from cuiidle. Equal to cuiidles. Specific giavily. At the end of the first hour Ditto ditto with 20-hole ) argand burner - - 5 When charge nearly off - When charge quite off, with 20- > hole argand burner - - \ feet. 5 9 inches. 70 25 85 100 2-72 21-33 1-84 notl •475 •475 •442 •266 3d Experiment, May 29.— Carlisle coal (Blenkinsopp). 112 lbs. produced 556 cubic feet of gas. Other products, loss of weight, &-c., same proportion as foregoin<' experi- ment. Average quantity of gas made from the charge (6 hours) 496 cubic feel per lb or J 1,120 per ton '* In this exj)eriment the quantity of gas generated every hour was ascertained • the illuminating power, the specific gravity, and the quantity of gas consumed by the s'in'^le jet with a flame 4 inches high, was tried at the end of each hour, with the respective gases generated at each hour ; and the following is a table of results. RESULTS. Consumed Hour. Gas producred. \if\ hour, per single jet, Specific gravity. Distance of candle from Illuminating power equal to 4 inches high. shadow. mould candles. cubic feet. cubic feei. inches. 1st. 150 j lU-lOths > or 1-15 J •534 70 2^72 2d. 120 11 •495 75 2-36 3d. 95 12 •344 75 2-36 4th. 95 15 •311 80 2-08 5th. 80 17 •270 85 1-81 6th. Total 16 29 •200 feet 9 inches. 100 not one 556 or 92ior2 92i 115 Average of the above gas, 6-hour charge. 16-lOths, nearly '359 81 Average of the above gas at 4-hour charge. 12|-10ths, -421 76 203 2^36 Troduction of gas in 6 hours 556 feet, or at he rate of 11,120 cubic feet per ton. Ditto in 4 hoars 460 feet, or at the rate of 9,200 ditto GAS-LIGHT. 863 The relative value of these productions of gas is as follows, viz. : 11,120 at 16-lOths per hour nearly (or 1-5916 accurately), and equal to 203 candles; the 11,120 feet would be equal to and last as long as 1597 candles, or 2661. lbs. of candles. 9200 at 12J-10ths per hour (or 12375 accurately), and equal to 236 candles; the 9200 feet would be equal to 1949 candles, or 324^ lbs. candles. Now 2661 lbs. of mould candles, at 7s. 6d. per^dozen lbs., will cost 8/. 6s. 4|d., whilst 3245 lbs. of do. do. at 7s. 6d. per do. do. 10/. 3*. Showing the value of 4-bour charges over 6-hour charges ; and of 9,200 cubic feet over 11,120 cubic feet. Note. — 9500 cubir feet of Wijran cannel coal gas are equal in illtuninating power to 859 l-6th lbs of can- dles, which at 7s. 6d. per dozen lbs. will cost 25/. lOs. b^d. It is also found that any burner with superior gas will consume only about half the quantity it would do with coinmou gas. ith Experiment, May 30th. — Cannel and Cardiff coal mixed | and |, together 112 lbs., produced 460 feet of gas; 2 bushels of coke of good quality; increase of coke over coal in measure, about 30 per cent. ; loss in woight, 41 lbs. ; coke weighed 71 lbs., no breize. Average quantity of gas made from the <-. irge (4 hours;, 4-1 cubic feet per lb., or 9-200 per ton. Illuminating power. — At the end of the first hour. Caudles. Distance of candle from ) -yo nr 9 AQ 5 Consumed per hour, single shadow - - _^'^oTz^if^ jet, 4 inche* high ^- At end of 2d hour, do. 70 or 2-72 Do. do. do. At end of 3d hour. This gas very indifferent. Average of the three - 70 or 2-72 Do. do. do. Specific gravity 3-44; 5 feet per hour, with a 20-hole argand burner, equal to 14-66 candles. blh Experiment, May 3Ut. — Carlisle coal, 112 lbs. produced 410 feet of gas; other products, same as in former experiments with this coal, but heat very low. Illuminating power and produce of gas. ''Average of this gas: specific gravity, 540; distance of candle from shadow, 55 inches, or 4-4 candles consumed per single jet, 9-lOths of a cubic foot per hour. 20-hole Cubic feet. 12-lOths. ll|-10lhs. ll|-10ths. flsi hour 120 cubic feet ^'""•^^ To { 4th 100 < argand burner, 4 feet per hour, equal to 21-33 candles. It is possible, from the superior quality of this gas, that a little of the cannel gas made for a particular purpose, may have got intermixed with it in the experimental gasholder and apparatus. A variety of other experiments were tried on different qualities of coal, and mixtures of ditto, too tedious to insert here, though extremely valuable, and all tending to show the superior value of gas produced at short over long charges ; and also showing the im- portance and value of coal producing gas of the highest illuminating power; among which the cannel coal procured in Lancashire, Yorkshire, and some other counties o£ England and Wales, and the Parrot or splent coal of Scotland, stand pre-eminent. Note. — In all the foregoing experiments the same single-jet burner was used ; its flame in all instances exactly 4 inches high. The coal when drawn from the retort was slaked with water, and after allowing some short time toi drying, was weighed. A Table of the number of hours Gas is burnt in each month, quarter, and year. , . . ^ a Xi 4) >. >» C9 3 3 3 Time of Burning. •s s 2" < •" M 3 U O > « U Q cs 3 a s u fa- < ^ S 6 s 3 »-3 ii a- u "3 C -3 Total year o'clock. From dusk to 6 — — 2 .11 02 80 65 33 4 _ ___ 2 173 102 277 ** y — 7 — 14 22 02 4-3 111 90 61 31 4 _ 4 30 205 18S 493 3 — 8 — 40 ."42 93 122 142 127 89 62 28 4 _ 32 92 .3.17 278 7.59 O — 9 13 71 82 121 152 173 158 117 93 58 29 8 95 106 449 308 1078 .-: — 10 44 10-2 112 155 182 204 1.S9 145 124 88 60 38 ISO 2.'iS .541 4.58 1443 !d:= — 11 75 133 142 180 212 235 220 173 155 118 91 68 277 3.')0 633 548 1808 ~ s — 12 106 104 172 217 242 206 251 201 186 148 1S2 9H .•?08 442 725 638 2173 All night 217 307 345 421 473 527 512 411 382 295 24S 195 732 809 1421 1305 4327 -3 9 Morning from 4 — 16 48 80 no 137 137 98 71 28 « 30 04 327 306 727 5g — 5 — — 18 49 80 106 106 70 40 3 _^ 3 IS 235 216 472 Kfi — 6 — — — 18 50 75 75 42 9 143 126 269 Im -- 7 1 20 44 44 14 ~~' —^ ^~ ~"^ ~~' 64 58 122 !^ 864 GAS-LIGin\ Copy of a Paper submitted to a Committee of the House of Commons in the Session of ISW, of England ; and procured by actual Survey and I 1 No. of Name of the Place where Price of Gas per Meter, Price of Coal, and Description ; delivered per Ton. Coks made frora a Ton of Coal. Selhn; Price of Ma- terial usual to Quail- used Public or Street Descnption. Price paid per Anpum Who ti^U, cleans, putseMi Gas Works are uiiuited. and Discounts allowed. ^2- Coke. heat Retorts. per Ton of Coal. Lamps sup- Bise or Sort. for Ditto. and repairs. i 1 plied. Cu./t. L. ». d. Birmingham Can Com- 10*. per meter cub. feet. Di«coiiiits Lump coal 6,500 33 8«. Id per Slack. About 490 Batswings. 1 10 8 Company, and from West bushels. quarter 5 cwt. 460 provides poata* pany. 10/. to 30/. s i'} . Bromwich delivered, of slack. ID services, &^. 30/. to SO/.* 4 c pits, risen or about at 6s. 50/. to 75/. t 7i S much of late. 3d. per per ton, 75/. to I00/.**I0 t 1837, lU. lOd. bushel. 25 per Brming'ham 100/. &- upwards 15 »• 10*. permetercub. feet. From West 6,500 24 bush. 2s. lOd. Slack. cent. 5 cwt. 1,500 Batswings. averare i la A Ditto. and Staf- Discounts as above. Bromwich but larger per sack and of slack. 1 18 fordshire. pits, 1837, 9s. 3d. measure than Bir- mingham. of 8 bushels. Tar. at 4«. 25 per cent. Macclesfield. 10«. per meter cub. feel. Discounts 50/. , 75/. 5 75/. - ^ 100/. 7, • •100/. 5^ 125/. 10 = 125/. -3 t I5'V, laiS 200/. I7ic- Common, 8s. average 1834. 6,720 IS cwt. lOs. per ton. Coke. No account kept. ISO Ditto. a 10 Company* Stockport. 200/.itiipwards20 10*. permeier c'lb. feet. Coal 10s. 6d. 7,800 7 cwt. 6s. 8d. Coal, Ditto. 830 Ditto I 1«K. Comm. proTida Di»cu'iitssame as Mac- cannel 194.6 30/. 7) { yearly ) SO/. 10 J payments. ( 100/. St. per ton averajsi. S-3ds. cola to 7s. l-3d cannel 10«. 6,500 Itcwu 7*. 6d. per ton. Ditto. 5|fwt. 517 DKo. 8 18 6 CominissiaMn.j except extin- • guishing, for 1 which Comp'ny pay 3*. lOil per lamp. Sheflie'd. 8». piT meter cubic feet. 7».9d. perton 8,000 10 cwt. I0«. Ditto. IJcwt. aoo Ditto. S 10 Compar.7 1836. Disc'nts same as Leeds. average. 3 sorts used, 1, S-lOihs caii'el.at 16*. 8, 2-IOths deep pit 7s. l-lOili silkslone, lOs. of saleable coke. oer ton. pr> vide lampa,j clt n, repair, i pu. out, &c. Lcirester, 7s. 6d. per meter cub.ft. I3»-. 6d. 7,500 4 quarters 10«. 8d. Coke, About 44 Ditto. 1 18 6 Compao) light. 1837 Disc'nls on half-yearly averatfe. Derbyshire or t*. 8d. tar, &c 1-Sd of put out, «d rental, not exceeding perqr. cc.ke. clean. 10/., 5 per rent. soft coal. 10/. „ V, 20/. 7\ . «20/. £■= 30/. 10 S >30/. -"3 40/. Iti S -=40/. = S 50/. IS u <50/. *g 60/. 20 %, 60/.&.upwards95 Derby. 1834. 10*. per meter cub. feet. Discounts i to 35 per cent. Same coal used as at Leicester. 7,000 Ditto. Ditto. Coke. Ditto. tI9 Ditto. 8 8 8 7 Commissionert light, put out, &.C. Nottingham, 9». per meter cubic feet. Ditto. 7,000 Ditto. Ditto. Ditto Ditto. 300 BItto. 8 8 Commiasioncra 1834. Discouuu as above. light, clean, repair, &c. London, 1834 ie». permetercub. feet. No discounts. 17». average. Newcastle. 8,500 26 bush. 12*. ytet chaldron. Ditto. 11 bush. 86,880 Ditto 4 C >n»patMr tight,! Cl'^ll, fttt ou*. b— 9V repi.ir Uitto.UI7. Dhto Ditto. 8,500 Ditto. Ditto. Ditto. Ditto. 80.400 Ditto. 4 -» "^ GAS-LIGHT. 865 b<>Ag a Synopsis of the proceedings of the undermentioned principal (ras-Light Establishmeata Experiments between the Years 1831 and 1837. By Joseph rlediey, Elsq. no. of Hours, orTime i.iiii ■ji liie Ifsii. Gas con- sumed in each Lamp per Hour. u w S.Z O S2S nights or 8^33 hutirs, 9 iiioiiths,nmit- ting 5 nights for moons. 8-^4 nights, or 304S liours. 8 months, omilliii|r 5 nights h>r 8 months, 4 nights omit- tedfor moons. 837 nights— ttOO hours. 1390 hours. 1000 hours. nearly similar 8000 hours. Smooths, emitting 7 Ibirhu. 8000 oours to 4 o'clock in the moruing. 5 feet hour. Ditto. 4 feet hour. Ditto. I foot. 8 feet, per hour. " = S • "3*- - 9 IS Vol «. d. 30 10 40 18 1 3i 8 t. d. 18 8330 hours. 8800 hours. From August 14th to September 1st, omitting I nights for aoons, 3000 hours. SITS hours, from August to May. All the year, 4887 hours 5 feet hour. results. Si feet per hour. (feel hour. 8 6 6 6 5 6 4 4 which 5 6 S 1 18 18 IS 6 nothin° 4 feet I.P" hour. Ditto. Sfeet per hour. Ditto. Ditto. f S s >i > 4I IS see. nothing IS 6 S 10 IS 7 4887 horirs, t all tba jiar. j per bour 4 nearly I nearly 4 feet 4 3 Ditt*. Oitta. 4 til Per Centage of Loss of Gas made. Receives net about 6*. 8d. per meter cubic feet. Receives net about St. 6d. per meter cubic feel. Could not say. Ditto. About IS to I7i per cent receive about 7t. 4d. per meter cubic feet, public and private. Nearly all by meter. Could not learn in the absence of the manager. Nearly all by meter. Receive 8s. per meter cubic teel, less 5| per cent .3 11 Receive for public and private OS. 8d. per meter cubic feet. Public 5*. private 7* ; meters used 5 to 1 for private rental. Receive for public and private Its. 5«. per meter cubic feet. Public S«. Std., private 5«. 9\d. Few meters used. Not sufficiently long, at 7«. 6d. Lose about 17| per cent. Could not learn. Receive for public and private lights 7«. public, ii. private, 8«. fe\ meters used. Ditto. Greatest Quantity of Gas delivered in One Night. Cubic Feet. 48 millions in the year. 85 millions in the year. 80,000. Total for year about IS millions. 65,000. Total for year about 18 millions. 500,000. Total for year 100 millions. 360,000. Total for year 72 millions. Not suffi- ciently long at work. 48,500. Total for vear 8,^19,000. 176,000. Total for year 81 millions. aso,ooo. Total for year 40 rnillioiis. Total for year 18 millions. Ditto. Ditto. Total for year 1000 millions. Longest night 4.910,000. Total for year 1400 millions. Longest night 7,180,000. Duration of Charges. Method of Purifi. cation. 6 hours. Ditto. 8 hours. Ditto. 6 hours. 3 hours, large retorts, hoMing 6 cwt. each. 4 hours. Dry lime. Ditto. Ditto. Ditto. Wet lime. Wet and dry lime, prin- cipally dry. Wet lime. Number of Gas Holders. 4, and 8 in the town, and large new gas station. 6, and 6 in the town 7 miles off. 3ga8 holders. 4 gas holders. 10 gas holders, and 8 in the town. 8 gas holders in all, 4 in tb« town, 1000 yards off the works. 8 hours. Dry lime 6 hours. Ditto. Ditto. Ditto. Ditto. Ditto. Ditto. Ditto. Ditto. Ditto. Wet lime Ditto. Ditto Ditto. 8 large gas holders. 4gas holders. o Is Q. OQ •453 <- 1 oOE) a o o.z <-< 9 *^ U o ^ 3 ^ — c j; 3 — o iii = 5 "^ 5 f-~ =-i um •455 Not taken •539 •534 86S •580 •4K) hoi' 1^1 lers. 4 gas holders, and 8 more erscting. 8 gas holders, and I erecting 4 gas holders. IIO gas holders. 176 gas hohurs. Inch, 72 JCarf/M 1,929 ,c o OS CuTrt. 1-28 c Cu./t. •8 70 64 66 75 M 78 •530 •466 •588 1,989, l-n I -8 804 Not taken 8,441 •85 = 25 • cr Inch. *i M 2,295 •SSS ; '475 1,777 SM I'l 8,306. -9 1,6481 n 67 74 74 •448 •424 •418 •418 63 90 60 80 8,888 1,836 •8M 1,886 104 M 1,453 1,884 Ik •t \U f ••• w I >l •7» 1-8 -M I 8 ' 1 i7S l,53li 1-iS I 84 l^ 8 8 n II •84 r ( SG6 GAS-LIGHT. II > e a D O 0) o 3 o 2 6- I >^ .«« «_ .^*i k _ «w% aMk X. ^ * * ^~ — oooooeoooooooooooooooo 3 «c«QDaD-T« a» o po Oi oj o o> p o s o s o o o o o o o o c o J- ;*-• -«^ ^« s._< w' 14V f" \JU f-^ S — ' — — O— OOOOO! o t-. » c* X — PO »^ >rt (0 bo o bo R 3 u CO >n -^ c^ "n 00 or :«> ^ '•^ -"* ^ *' ^ ■* >*■• ^" ^^ 'w^ ^-' 'ju w^ uj gu 1^ QD f^ I'- ?C f^ * 3 O ^ tSit^ X !0 -n CO -^ c* . 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Bffr Tbials of, and Experiments on, various Kinds of Coal as regards the Production o Gas from each, and its Quality or Illuminating Power; by Joseph Hedley, Esq., Co»- sulting Gas Engineer, London. Note.— In ail the experiments the gas was passed through a governor, on a pressure of 5 lOths of «■ Inch. 1. 8. 3. 4. & ft. 7. & 9. la IL IX 13. 14. IS. 1& If. Haine and « or Tube with- Oths of an Inch,! ight of Flame. j 1 a -J o o '•S >. X 1 St Equal in Illuini- s ; outer Diameter nch ; inner ditto Holes 40th of an Distances apart, ; full Illuminating Candles; consum- itli 30 Holes ; outer Diame- Inch ; inner ditto 7-8 of an oles 40th of an Inch Di- Distances apart, llOth of full Illuminating Power 36 Candles; Consumption i i "a a 9 ^ i i 1 Description of ?;^x fL S S o S o o I" ffO* <0 !-• -< ft" t) 5 I. t-l C 3 '- 11 H tn w -< < o . H ^.ti i U.J «i J «rf • ■s«; UU s«> •J J 11 n Inch's ^u pd -^i ^8 Candle* Cubic Feet Cubic Feet. ?§ n.S 3 •^^ •§8 ■ss ■i^ ui* a oi* 0&. «,li », o>* K ot* o"^ oh. w«* u»* §►.; Lismabago, or Glaagow Can- f nel - • • • 91to2a 13 li 12-1 7-3 2-77 B-8 3-9 •737 101 l» 39 37 33 11 < 1 Hewcaatle coal 18 16 16-2 ll-l 1-76 6- 7-5 .476 104 30 30 18 16 16 « 1 Welsh Cannel 23 11 9 131 71 3- «• 8- •737 103 s 60 30 30 8 1 Pelaw, New- castle Coal • 18 16 »^ 16-1 HI 1-75 »• 7-5 •444 1(» 3 S9 30 17 14 « Pclton, ditto - 18 16 16-3 U-3 1-73 6* 7M .437 103 3 38 20 19 14 6 Bickers talf, Li- ' verpool ditto 19 14 ei 16-3 111 3-04 4-e 6-S .476 103 3, 30 34 18 10 4 Wigan Caanel S3 11 » 131 7.2 3- 8- 3- .606 100 ^k 38 30 18 4 Blenkinsopp, Carlisle Coal • 27 16 ?» 161 11-1 1-87 4-6 7. •631 100 3 98 84 18 10 Neath Coal - 18 16 191 121 W6 6-23 7-5 •468 100 3 96 81 SO 18 » Note.— The candle here used was a composition candle, with plaited wick, requiring no snuffing firing at least one third more light than mould tallow candles. Attention to the preceding tabular statement of experiments is important, as exhibit- ing several very important facts, particularly interesting at this moment to the science of gas-lighting, and now for the first time made public. It will not fail to be observed by these experiments that all the coals produced nearly equal quantities of gas, notwithstanding the variable characters and qualities of this coal. The greatest quantity produced being at the rate of 11*648 cubic feet per ton of 20 cwt., the smallest 1 1'200 cubic feet. All these experiments were performed with the greatest care, and under precisely similar circumstances as to pressure, manufacture, &e., &.C. The time in which the quantity of gas is produced from the several coals varies con- siderably, and deserves notice, as it most materially affects the economy of production — that coal being the most valuable, all other things being alike, which yields or gives oat its gas in the shortest time ; and particular attention is claimed to this fact. For the more ready reference to the table the columns are numbered. No. 11 exhibits this difference, and it will also be seen by this column that the time varies as the quaiUf of the coal, the best coal yielding its gas in two hours, and the worst in three hours. Another most important, material, and interesting fact is established by these experi ments— that the fiow of gas is as its density — demonstrated by the variation in the heights of the flames, as shown in column No. 1, being 18 inches in the inferior gase* to 22 inches in the superior; while the quantity of gas required to supply these flamea is in the inverse ratio of their heights, the longer flame requiring but twelve cubic feet to maintain it, when the shorter flame, from the inferior gas, required sixteen cubic feet. See column No. 2. Remarkable as this difference in the heights of the flames and the consumption is it is not so great as the difference caused by the quality or illuminating power of the several gases, shown by columns Nos. 5 and 6 ; where it will be seen that the consump* tion of the best gas per hour was only ^- of a cubic foot, and its light was equal to 3 candles, while that of the worst gas was |,2 ©f a cubic foot, and its lights equal only to 1*75 candles, or nearly, the best to the worst, as 1 to 3. The next column. No. 7, exhibits similar results as to the superior value or illumina. ting power of one gas over another. In this case an argand burner was used. The best gas required only two feet to be equal to twelve candles, while the inferior required five feet to be equal to the same. And in column No. 8, in which another and superior argand burner was used, the best gas required only three feet to be equal to twenty-five mould candles, while the inferior required seven and a half feet : from this it results that the 7^ cubic feet of 898 GAS-LIGHT. I inferior gas, to be equal to the 8 feet of good gas, should have given light equal to nxty two and a half candles, whereas they only gave light equal to ttoenty-Jiw candles, to great is the difference in the qualitus of gas for jn-oducing light. Whilst on the subject of the illuminating power and the value of one gas over another, it will not fail to be observed, by the table, that another great difference also exists, caused by the use of particular burners ; as, for example, the best gas in column No. 6., where the single jet was used, required teventenths of a cubic foot to be equal to three candles, whilst the same gas in column No. 7., where a 20-hole argand burner was used, required only two feet to be equal to twelve candles ; and in column No. 8., where a 30-hole argand burner was used, only three feet were required to be equal to twenty-Jive candles ; demonstrating the fact that a great and extraordinary improvement in the quantity of illuminating power is effected by the simple increase or enlargement of the burner, affording, where great light in one position is required, a most extraordinary economy in the use of gas, shown in fact Sractically by the recent introduction of the celebrated "Bude" light, patented by [r. €k>ldsworthy Gurney. Tabular Statkmknt, deduced from the foregoing Experiments, showing the Cost of Candles to produce as much light as 9,000 Cubic Feet of Gas would afford, being the Product of One Ton of Coal. (The candles are moulds, 6 to the pound, 9 inches long, and each candle is calculated to burn 9^ hours. Cost of Candles lyL per pound, or 7». 6d per dozen pounds.) CWdlw would eeat, to be «qiiiTaIent to Where a single Jet Earner it lued. Where a 30-hole Argand Burner is used. WherBa30-bole Argand Burner is used. Where a Bude Burner is used, according to Slatement of Company. Common coal gas ------ Qood do. -----.- - £ s. d. 10 18 6 25 18 4 £ H. d. 15 15 8 89 9 6 £ «. d. 21 18 e 54 16 7 £ ». d. 59 8 7 148 9 Tablk, also deduced from the foregoing, showing the Cost of Gas at the several Prices undermentioned, and equivalent to 100 lbs. of Mould Candles, coatinjr Zl 2«. 6(1 * •fG^. If burnt in a Single Jet Oaa «qiial to 100 lbs. of Mould Gindles. Gas would cost at per thousand Cubic Feet. If burnt in a 30-hole Argand Bam«>r, Qa» equal to 1(10 lbs. of Candlrs. Qm would eoet at per thousand Cubic Feet. If burnt in a 80-hole Argnnd Burner, Gas equal to 100 lbs. of Cai.dles. Oaa would eoet at per thoussdd Cubic FeeU Oommon Good - Cubic te«t. h,. Is. 9«. Cubic feet. 6«. It. 9t. Cubic Feet. 6s. 7*. »«. 2,687 1,072 t. d. 13 5 6 4 t. d. 18 9 7 5 (. d. 24 2 9 7 1,781 712 8 10 8 6 t. d. 12 5 4 11 I. d. 16 64 1,282 513 «. d. 6 5 2 7 t. d. 8 11 3 7 «. d. 11 « 4 7 I have received from Mr. Hedley, an engineer of great eminence and experience, plans and drawings of gas works and of apparatus of the most approved and modem construction, and on the very largest scale as to extent of business or manufacture : also plans and drawings of a gas work on a smaller scale, with its corresponding apparatus. In the first, or large work, purification by wet lime, before described, is used; in the latter, by dry lime. The large work referred to is calculated for and is arranged to contain 400 retorts, 12 wet-lime purifiers, and 2 washers; 12 large double or telescopic gasholders, capaHe of storing 1,000,000 cubic feet of gas ; and coal stores capable of holding 10,000 tons of coaL The smaller work is calculated for and will contain 40 retorts, 2 dry-lime purifiers, and a wash vessel ; 2 gas-holders capable of storing 50,000 cubic feet of gas ; and coal stores sufficient for 1000 tons of coaL Fig. 687. is the side elevation (front view) of a gas work capable of containing 400 retorts, and all their dependencies. Mg. 688. is the plan of the retort house, coal stores, tanks, gas-holders, Ac, on the largest scale and most approved form, viz., a the retort house, 300 feet long, 56 feet wide ; b, retort beds ; c, chimney stack ; d, flues ; k, hydraulic mains ; f, coal stores, each 300 feet long, 30 feet wide; g, condensers; h, engine houses; j, wash vessels; k, purifiers and connections; l, lime store and mixing tub; m, smiths' and fitters' shop; n, refuse lime pits; o, meter houses; p, tar tank; q, tanks, gas- holders, bridges, columns, valves, and connections ; a, governors ; a, coke stores ; T, inlet pipes ; v, outlet pipes ; w, house and offices ; x, stores. GAS-LIGHT. ; Fig. 689. TntDsverse sectioo and elevatioo of a bed of 6 d retorts ; a, transyerse Mction ; b, elevatiop. «87 J fi -5v i 1 I 870 GAS-LIGHT. Fig. 690. Longitudinal section of a bed of 6 d retorts. Fig. 691. Elevation of an upright air condenser,' consisting of 6 chambers, with ft series of 10-inch pipes. J^^. 692. Elevation of a double or telescopic gas-holder, of a modem and approred form, with part of tank. GAS-LIGHT. 871 688 tig. 693. End elevation and plan of air condenser ; a, end elevation ; b, plan. ^g. 694. Set of 8 wet-lime purifiers and wash-vessels in elevation and section, with feed-heads, agitators, valves, ana connections, raised for the lime liquor to run from one purifier to the next below it, and ultimately into the refuse lime-pits, viz. a, section of wash- vessel ; b, section of purifier ; o, elevation of purifier. Fig. 695. Front elevation of gas works on a smaller scale, where dry lime is used. Fig. 696. Plan of gas works, consisting of, viz. : a, retort house; b, retort beds; C chimney stack ; d, flue ; s, hydraulic main ; r, coal store ; o, lime store ; h, w»*hor and purifiers ; j, store ; k, tar-tank ; l, horizontal condenser laid on the p'-jund ; M, inlet pipe; n, outlet pipe; o, tanks and gas-holders; p, meter and f rernor ; q, smith's shop ; r, office ; 8, coke store. 87SI GAS-LIGHT. GAS-UGHT. 873 11^ f Fig. 697. Elevations and sections of dry-lime purifiers ; a, longitudinal elevatioa ; b ditto section ; c, transverse elevation ; d, ditto sectioa London, Manchester, Liverpool, Birmingham, Chester, Bristol, Ac. <&&, in all which places lie has erected gas-works. To this gentleman's genius and skill the public are mainly indebted for many valuable improvements in the application of gas from coal to purposes of illumination. 693 '^ y= I am well convinced that a distribution and arrangement of gas-works, combining eflbctiveness, economy, convenience, and elegance, at all equal to the preceding, havs never before met the public eye, in this or any other country. H^ Ih the brief description of the meter given in this Dictionary, I omitted to state, that this most ingenious scientific contrivance for measuring aeriform or gaseous fluids as they flow through pipes is the invention of Samuel Clegg, Esq., Civil Engineer, of l< • WH GAS-LIGHT. Brought up m ihe great engineering establishment of Messrs Boulton and Watt. ^L K^'T" ^^*;?"»g^*?^' he became connected with Mr. Wm. Murdoch, who moet rrZr!.1?/^.T/K w'''*'*'' ^*^^<>"g»°»t<»- of gas-lighting, as the evidence given before » Committee of the House of Commona in the year 1809 abundantly verified. H« II i GAS-LIGHT. 87ft demonstrated that the light produced from gas was superior in economy to all other modes of artificial illumination; and by tfeat evidence, though so long "back as 1809, it will be seen that all the information of the present day was even then known to him, dearly pomted out, and illustrated by his experiments, which strangely contrasted 876 GAS-LIGHT. GAS-LKJHT. 877 Fig. 62. Elevations and secUons of dry-Ume purifiers; A, longitudinal elevaUoB U; ditto section ; C, transverse elevation ; D, ditto section. 697 ^ B S2 o 1 1 _i ^ o ..,<;> ^ • 1 K . . t 1- -?- llL Jl "With the statements put forward by the parties then attempting to introduce this mode of lighting into the metropolis. All the ephemeral plans of those parties, have, how- ever, long since disappeared, or nearly all. One, unfortunately, remains, and that a most unlucky one— the unprofitable manufacture of coke in gas-making— an article worthless in the scale of value, which should never have been sought for. Messrs. Watt and Murdoch predicted that when the parties became incorporated by Par- liament, they would resort to their apparatus, notwithstanding their repudiation of it at the time, alleging their own schemes to be so much superior ; and they verified this prediction a very few years afterwards by engaging the services of Mr. Clegg, to extri- cate them from their manifold and egregious errors. He began by introducing the very apparatus of Messrs. Murdoch and Watt, so inconsiderately condemned by them. Mr. Clegg put up the Jirst gas-holder ever erected in London. To Mr. Clegg is due also the introduction of lime for the purification of the gas, without which gas-lighting would to this day have afforded little comfort and economy. The hydraulic main, for separating the gas making from the gas made, valves, lutes, and many other admirable contrivances, are peculiarly due to Mr. Clegg. But the crowning performance of all his inventions, was that for measuring out the gas to the several parties rec^uiring it exactly according to their demands. The manu- facture of gas having by this time been so far mechanically perfected as to be brought to our doors, it became at once apparent that some contrivance should be found by the use of which every person might consume as much or as little gas as he pleased, paying only for what he really used, thus making science subservient to fair dealing. Mr. Clegg took out a patent for the gas meter about the year 1814 ; but great as its merits were, he soon found that serious difficulties remained to be overcome, in in- ducing parties to support and encourage its use, even where their interests should have prompted them to adopt it. Mr. Clegg had, however, fortunately associated with him, towards the completion of the apparatus, Mr. Samuel Crosley ; and by their joint labours it acquired its present precision. The value of the meter is primarily to the gas companies, next to the public. By its use, the gas companies are enabled to supply gas to all places where light is re- quired, at a rate proportioned to its just value. The public thereby see the economy afforded by gas over candles, oil, or other material ; but they gain also in another most important way— by the use of the meter, gas companies, being duly i*id, are eiwbled to reduce the price of gas, and yet realite e^'\tal projits, thus bringing it within the reach of a much larger class of the community ; and it is a well established fact that in towni where gas is sold by meter, gas companies can and do sell at nearly one half the price they otherwise could do. Reduction of price increases demand ; increased demand increases profits ; increased profits again enable prices to be reduced ; and again, reduced prices increase the demand, thus benefiting reciprocally companies and consumers. Notwithstanding, however, all these advantages, there are not wanting persons whc have set up an outcry against the use of the meter, by impugning its accuracy, and accu- sing Ihe gas companies with fraud in charging by it. It would be idle to follow these parties in their baseless allegations. An action for pirating it was brought and tried in the Court of King's Bench, in which not only the novelty of the machine was fully estab- lished, but its accuracy and usefulness proved by the ablest mathematicians, mechanicians, and chemists of the day ; and a verdict in its favour obtained. Subsequently very large damages have been given for the infringement — in one case as much as 5000<., and in an- other, in the Court of Chancery, a decree was made referring it to the Master, to take an account of the profits made by the use of the meter ; this is not yet finally settled, the Master's report finding 6000/. to be due ; but this is excepted to by the parties infring- ing : the Chancellor, however, allowed the exceptions to be ai^ued, only on payment by the infringers of 4000/. into court to meet the patentee's law costs. These exceptioiis have no reference whatever to the question of the accuracy of the meter, but are simply as to whether the advantages of the meter were as great as allowed by the Master. The patent for the meter expired about the year 1828 ; since that period numerous competitors have commenced making the machine. Mr. Clegg has recently obtained a patent for a dry gas-meter, of which the following are its advantages and construction, as described by the very meritorious inventor : — 1. Working without water. 2. Working without membranes or valves. 8. Working without requiring the least pressure. 4. Working without interference with the perfect steadiness of the lights. 6. Registering more accurately than any other meter. 6. Occupying only one- tenth of the space of the common meters. 7. Being subject to little or no wear and tear. 8. And being cheaper. J'riees. — For plain meters.— £ ». d. Three-light meter .... 1 12 Six-light do 2 4 Twelve-light do. .... 8 80 The highest numbers will be still cheaper in proportion. Ornamental meters, appearing like handsome time pieces, for halls, living-rooms, com mittee-rooms, offices, counting-houses, Ac., are charged extra, at ten shillings each and np wards, according to pattern. Description of Clegg s patent dry Gas-meter. The two ^gs. 698,9. are half the full size of the apparatus, and the letters of referenot are the same in both. B, B, Jig. 698., represents a cylindrical vessel, about three inches and three quarters diameter, and four inches deep, being the dimensions of a meter capable of measuring gas for three burners, called a three-light meter. In this vessel are two glass cylinders F, F, connected together by the bent tube d. The cylinders being perfectly exhausted of air, and half filled with alcohol, are made to vibrate on centres e and «, and are balanced by the weight/. This instrument accurately indicates the excess of heat to which either cylinder may be exposed, upon the principle of Leslie's differential thermometer. C is a hollow brass box, called the heater, about four inches long, and half an inch broad, projecting out of the meter about one inch. At a issues a small jet of gas, which, when inflamed, gives motion to the cylinders. The gas enters the meter by the pipe A, and circulates throughout the double case B: having passed round the case B, a portion of it enters the top of the box C, by the pipe D, and passes out again at the bottom by the tube e, into the meter ; the rest of the gas enters the body of the meter through holes in the curved faces of the hoods EE, and, after blowing on the glass cylinders, passes to the burners by the outlet pipe. To put the meter in action, let the jet a be lighted about an hour before the burners are wanted. In most cases this jet will be lighted all day ua a useful flame. The 878 GAS-LIGHT. hole a }4 so situated on the box C, that whatever be the size of the jet, a fixed tem- perature is given to the box, that temperature depending on the quantity of flame in ft 1 ' > ii U contact with the box, and not at all on the length of the jet. The jet being lighted, and the box C thereby healed, the gas which passes through it is raised to the same temperature, and, flowing out at the tube c, impinges on the glass cylinder which happens for the time to be lowest; the heated gas soon raises a vapor in the lower cylinder, the expansion of which drives the liquid into the upper one, until it becomes heavier than the counterpoise/, when the cylinders swing on their centre, the higher one descends, and comes in the line of the current of hot gas, and the lower one ascends; the same motion continues as long as the jet a burns. The same effect on the cylinder is maintained, however the outward temperature may change, by the cold gas, which, issuing from the curved side of the hood EE, impinges on the uppei cylinder, ard hastens the condensation of the vapor which it contains. The coU gas and the heater vary in temperature with the room, and thus counteract each other. The lighting of the jet a is essential to the action of the meters ; in order to insure this, the supply of gas to the burners is made to depend on it in the following manner. The pipe G, by which the gas leaves the meter, is covered by a slide valve, which is opened and shut by the action of the pyrometer g ; the pyrometer is in communication with and receives heat from the jet, and opens the valve when hot, closing it again when cold. The speed at which the cylinders vibrate is an index of the quantity of heat com- municated to them, and is in exact proportion to the quantity of gas blowing on them through the pipe c and curved side of the hoods EE. The gas passed through the heater is a fixed proportion of the whole gas passing the meter ; therefore the number of vibrations of the cylinders is in proportion to the gaa consumed. A train of wheel-work, with dials similar to thai used in the common meter, regis- ters the vibrations. Simplicity, accuracy, and compactness, are the most remarkable features of this instrument, and the absence of all corrosive agents will insure its durability. GAS-LIGHT. Directums for fixing and using Clegg^s patent dry Gas-meteru 879 Choose a situation for fixing the meter, where the small jet of flame will be of the greatest use, such as an office-desk or counter, taking care to screw the same firm and level on its base. When the jet at the top of the meter is required to be kept con- stantly burning as a useful flame, press in the brass knob at the front of the meter, and before lighting the burners pull it out ; when the small flame is not required, let it be lighted about an hour before you want the burners lighted. Adjust the size of the small flame at pleasure by the screw h. On the back of each meter is marked the number of lights it will supply. The inlet and outlet pipes are marked at the bottom of the meter. The ((uantity of gas consumed is recorded by the index in the usual way. For testing Clegg's patent dry Gas-meters. Pass the gas through two meters at least, and take the mean. Vary the number of lights at pleasure, not exceeding the number marked on the meter, and when one or two hundred cubic feet of gas have been consumed, compare the indices. These meters are not for measuring small fractional parts ; but taking the average for any periodical consumption, are more accurate than any other meter. Mr. Thomas Edge, of Great Peter Street, Westminster, has contrived the following meter, of which drawings are annexed. Fig. 700 is a front view of a three-light meter, the front pl&te bemg removed, and •ome of the parts shown in section 65. Fig. 701 is a transverse section of the same. ^ . , . , The gas enters at a into the small chamber b, in the bottom of which is a lever valve (part of Mr. Edge's patent improvements), moving upon its axis and attached by the rod to a metal float c, which in the present drawing is buoyant. The object of this arrangement is to intercept the passage of the gas into the meter, unless a sufficient quantity of water is in it, that being necessary to its proper action; the gas then passes through the inverted syphon or tunnel into the convex cover, whence it passes into the chambers of the drum. Another of Mr. Edge's improvements consists in the cutting down of this sypnonpipe or tunnel to the proper water level, and connecting the bottom of it to a waste water- box into which any surplus water must fall. The importance of this precaution will be t^een on investigating the drum, as an excessive height of the water will materially interfere with the measurement, the quantity of gas delivered per revolution being considerably less. This, in connexion with the lever valve and float, conhnes the 880 GAS-LIGHT. GAS-LIGHT. 881 i li rariJition of the water levels within such narrow limits, that the measurement may be considered perfectly just on all occasions. ^^_^^^^_^__^ The last patent by Mr. Edge is for an* improved / \ II index, which is composed of a series of moving j I dials, with 10 figures upon each, one figure only ap- I 701 pearing of each series at a time. I This contrivance is very ingenious, and will no I I J doubt be applied to other machines, where indexes (indices) of quantity are required. Recurring to Mr. Clegg, he is also the inventor of an instrument of great value— appropriately called a "governor." Its purpose is to render equal the height of flame of the several burners in any house or establishment, and to keep them so, notwithstanding any, and whatever alteration may be made in the pressure at the works or elsewhere. This instrument is perfected, and successfully ap- plied, though it is not so generally in use as it ought to be. By the use of this instrument a light once set at the height desired will maintain that height uniformly, and without the least variation the whole evening; and continue to do so till altered. Without this instrument, it is necessary to pay attention to the burning of gas-lights, as their heights are frequently affected by the most trifling circumstance, such, for example, as their extinction at the hour of closing the shops, which makes a sen- sible diiference in the neighborhood. All these works have prodigiously increased in the quantity of gas made and sup. phed. Since the account in the former edition of this work, large additional manufac- tories have been erected by new companies, and great additions made by the old ones. Ihere are now in the metropolis alone 15 public gas companies, having among them 16 gas establishments. The quantity of gas manufactured by these 23 gas-works, and supplied to the pubhc was during the past year three thousand one hundred millions Ar.^^.^^ ^^^ °^^^ ' *^^ ^^® *=°^^ ^sed to produce this quantity of gas was at the least 400,000 tons I Baked clay retorts are very generally used in Scotland, and found to be most economi- cal as regards wear and tear; in London, however, they are mostly of cast iron. T A P^^^^^**^^ "P®** ^^6 retorts is caused principaUy by the use of wet lime, used in London, because the process is less expensive and less cumbersome than dry lime. Wet lime can not be used with clay retorts, owin? to this excess of pressure. Merit is due, for enlarging the capacities of double gas-holders, to the late Mr. Joshua Horton, of West Bromwich, near Birmingham; and to Mr. Stephen Hutchinson, engineer of the New London Gas- Works, Vauxhall, where they were first successfully mtroduced, and manufactured by .vir. Horton. They have now come very generaUy into u»:; throughout the kingdom^ and are manufactured by all eas-holder makers. "^ Separate gas-holders are advisable and advantageous, but they are not generally ased, except in Glasgow, Manchester, Birmingham, Sheffield, and a few other places. llie annexed drawing represents Mr. Croll's vessels for the purification of gas fVom ammonia, which is effected by means of dilute sulphuric acid applied between the con- densers with the ordinary lime purifiers. The vessels are made of either wood or iron, and lined with lead ; have a wash-plate similar to the wet lime purifiers. The radi- ating bottom formed of wooden bars, as shown in the drawing, is for the purpose of tupportmg the wash-plate and distributing the gas. Fig, 702 : a, is the inlet pipe ; 6, the outlet pipe ; c, c, the tube with funnel for introducing the sulphuric acid; d, the first purifying vat; e, the second ditto, both lined with lead, and which are filled up to the dotted line with the dilute acid • f f .he water supply-pipe ; g, g, the discharging cocks. Fig.noz represents a ground-plan of the vats, each 10 feet in diameter; A, the bottom of the middle ; B, the inlet of the gas ; C, the outlet of ditto. In commencing the process, these vessels are charged with water and sulphuric acid, m the proportion of seven pounds, or thereabouts, of the latter, to 100 gallons of the former. As the acid is neutralized by the ammonia contained in the gas passing through the vessels, the above proportion, as near as may be, is kept up by a continuous dropping or running of acid, regulated according to the quantity of ammona contained in the gas, from a reservoir placed on the top of the saturator. This mode of supplying the acid is continued until the specific gravity of the solution arrives at 1170, or cloM to the point of crystallization, after which the supply of acid is discontinued, and the liquor retained in the vessel until neutral, when it is drawn oflf and evaporated, and yields a pure sulphate of ammonia. This process has been introduced at several of the provincial gas-works, the three stations of the Chartered, the Imperial, Phoenix, &c., &c. Mr. Croll is also now in treaty with several other companies for its introduction. The produce — sulphate of ammonia — from the process, by the gas-companies using It, now amounts to several tons per week — and it may be here mentioned, as one of the advantages of science, that the ammonia so produced before the adoption of this process passed along with the gas to the consumer, destroying rapidly the main pipes, fittings, and metres, through which it was transmitted, as well as deteriorating the illuminating power of the gas, and producing a choky efl'ect when consumed in close apartments. It is now employed as a manure, and found to be superior in its effects as a fertilizer, as well as comparatively cheaper than any of the other artificial manures ; so that whether Mr. C.'s invention be looked upon as affecting improvements in the manufacture of gas, hitherto unknown, or as producing a valuable manure, the results are alike of the utmost importance. (When Mr. Croll's process is employed before the lime purifiers, dry lime can be used without creating the nuisance hitherto complained of, and a much less quantity ia required for this purification.) Mr. Croll has recently patented another invention, connected also with the manufac- ture of gas, which consists in the combination of clay and iron retorts, so that the heat of the furnace first acts on the clay retorts and then passes to those of iron. The annexed drawing is a transverse section • — A is the fireplace. B B are piers of fire-bricks, placed at intervals to form nostrils or flues, and the fire tile resting upon them in conjunction with the front and back wall, form the bed or support of the clay retort 1, and the clay retort 2 is also supported by the front and back brickwork, and a lump, or fire-brick, e, placed midway on the crown of the retort 1. F is a wall which separates the clay retorts 1 and 2, and the iron retorts l°and 2®; a space being left between the top of the said wall f, and the under surface of the arch, to allow the fire or heated air to pass freely from the clay to the iron retorts. G G is the bed, and h h is the flue under the iron retort 1°. The retort 2® is sup- ported by the front wall and pieces or lumps. J, placed at the back and crown of the retort 1®, in connexion with the horizontal flue. H is a vertical flue, forming a passage thence into the shafl or chimney. The heat passes from the furnace or fireplace a, through the spaces or nostrils formed by the piers b b, and around the clay retorts 1 and 2, over the wall f, descends between and around the iron retorts and along the flue h, and escapes by the vertical flue into the chimney. The advantages of this mode of setting retorts are the small quantitv of I / 1 I 11 882 GAS-LIGHT. brickwork necessary for the erections, the increased durability of the retorts, and iic economy in fuel. From adopting th?s mode of setting a brick lump^ it has beea fa.ind that 12 tons of coke will carbonize 100 tons of coal. gas-light. 883 le then employed as above indicated. It is also proposed to conduct carbonic oxide gas into retorts containing carbonaceous matters under distillation. This gas the patentees obtain from carbonic acid, by passing the latter gas (which may be obtained from any GAS-LIGHT. 893 convenient source) through a retort or furnace containing red or white hot coka Or, they utilize a portion of the gases generated in furnaces, by collecting these gases and converting the carbonic acid they contain into carbonic oxide, by passing them through a retort or furnace, as descril)ed for treating carbonic acid ; or the gases may be con- ducted directly into retorts, wherein carburetted hydrogeu is being generated, for the purpose of effecting the desired combination. From the foret'oing description, it will be understood, that the object of this part of the invention is to obtain gas of a uniform quality, — that is, possessing a definite amount of illuminating power. Now, it is well known that if the gas be too rich in carbon it will burn with a dull flame, and give off a large amount of smoke ; and that, if deficient in carbon, it will burn with a blue flame, and possess very little illuminating power. It is therefore proposed to mix the rich and poor gases, obtained as above described, in such proportions as will be needful to produce a highly illuminating quality of gas. As the proportions will depend entirely on the quality of the gases to be combined, no rule can be laid down for the aniount of the gas required to be passed into the retorts, wherein the distillation is proceeding. The mode, however, in which the gas burns, on issuing from the retort, will be a sufiicient test for the workmen in attendance. The second part of this invention refers to the purification of coal gas from sulphu- retted hydrogen ; and consists in effecting this operation by the use of what has been considered by chemists to be the ferrate of potash, but what is now found to be a per- oxide of iron in a peculiar state, and such as results from the employment of the follow- ing means : — First the patentees heat together peroxide of iron and caustic potash or soda to a dull red heat, by which a kind of ferrate or ferrite of potash or soda is pro- duced ; and when this substance is washed in water, it undergoes decomposition, with the reproduction of caustic potash or soda (which remains in solution), and the precipi- tation of peroxide of iron in the state fit for the purification of gas. All or any of the peroxides of iron may be used for the above purposes, and will, by its means, become useful for purifying gas, though previously inert ; and the solution of potash or soda, when evaporated to dryness, may be again and again employed upon fresh portions of peroxide of iron, so as to communicate to them the peculiar property desired. Or per- oxide of iron may be heated with a smaller quantity of caustic potash or soda, and a portion of common salt, in order to economize the potash or soda: the heat in this case should be, as before, a dull red ; and the same measures must be adopted for recovering the potash or soda and common salt, which may be used over and over again with fresh portions of peroxide of iron. Or the patentees heat the common hydrated peroxide of iron, to about 600o Fahr., — taking care that the heat never reaches a bright red ; and in this way they obtain a peroxide of iron, having the requisite properties. Or they heat in the same way, and with the same precautions, such of the native ochres or ferru- ginous compounds as will, after such treatment, become rapidly black upon being sub- jected to the action of a stream of sulphuretted hydrt^en. A quantity of peroxide of iron, fit for purifying gas, having been procured, by any of the means thus indicated, the oxide is next to be mixed with sawdust or other con- venient material, and damped slightly with water ; and the mixture is then to be spread in a dry lime purifier, and used in the way adopted with hydrate of lime ; or it may be mixed with water, and run into a wet lime purifier, and used in the way adopt- ed with regard to lime when employed in this kind of apparatus. In both cases it will be necessary, after the peroxide of iron has ceased to act upon the gas, to expt>se it to the air, by which its energies are renewed, so that it may be again and again used for the purification of gas. With the dry lime purifier, simple exposure is all that is re- quired. With the wet lime purifier, the mixture must be run out and left at rest for some time ; then, when the fluid has entirely separated from the solid part, it may be allowed to escape ; and as the solid portion dries, its power will become renewed : after which it may be mixed with water and employed as before. The renewal of the peroxide of iron, in both these cases, is known by its changing from black to red or deep brown. Another part of the invention relates to the use of the sulphite and bisulphite of lead for the removal of the sulphuretted hydrogen from coal-gas. These substances are to be employed singly or together, mixed with water, in a wet lime purifier, exactly as is practised with regard to lime. When they cease to purify the gas, the mixture is run out of the purifier ; and after the water has been removed by subsidence and decantation, or by a filter, the residue is dried and burned, so as to make sulphurous acid, which is employed in the manufacture of fresh sulphite or bi- sulphite of lead, or in the production of sulphuric acid. The matter which remains, after this burning process, is carefully roasted, and thus converted into oxide of lead or litharge, from which sulphite or bisulphite of lead may be again produced. The patentees claim the combining of gases which possess different degrees of illu- minating power, by the introduction of gas, obtained in any of the ways above iihlicate»| into retorts or vessels containing carbonaceous matters under distillation. They also 894 GELATINE. claim, as their improvements in the purification of gas, First, — the use of anhydrous per- oxide of iron prepared as above described ; and. Secondly, — the use of sulphite and bisulphite of lead, for the removal of sulphuretted hydn^en from coal-gas. — Neioton's Journal. We are indebted to Mr. Thomas G. Barlow, an eminent engineer, for a vast body of information on coal-gas, contained in his excellent Journal of Gas Lighting, commenced on the 10th of February, 1849, and continued in monthly numbers ever since. His first number presented a list of the London Gas Companies, and the value of their shares at the Stock Exchange, to which we have added the ruling rates in the present year. Paid up. £ 25 160 60 50 50 50 60 50 49 90 25 Name. Commercial . - - City of London - - Chartered - - - - Equitable - - - - Imperial Independent - - - London (Vauxhall) - Ditto (preference) Phoenix Ratcliff South Metropolitan - January, 1848. £ £ 25 to 26 285 — 290 58— 69 38— 39 80— 84 35 J to 86J 18 — 80 28 — 80 January, 1849. £ £ 25 to 26 240 — 245 48— 49 33— 35 62— 64 60— 62 10— 20 20— SO 28— 30 72— 74 21— 23 September, 1852. £ 30 124 36 — 26 — 76 — 46 — 2i- 15 — 26 — 60 — 20 — £ to 32 — 126 — 87 — 26 — 80 — 47 3 18 27 65 22 GENERAL SUMMARY. For lighting London and its suburbs with gas, there are — 18 public gas works. 12 do. companies. 2,800.000/. capital employed in works, pipes, tanks, gas-holders, apparatua 450,000/. yearly revenue derived. 134,300 private burners supplied to about 40,000 consumers. 30,400 public or street do. N. B. about 2650 of these are in the citt/ of London. 380 lamplighters employed. 176 gas-holders; several of them double ones, capable of storing 6,500,000 cubic feet 890 tons of coal used in the retorts on the shortest day, in 24 hours. 7,120,000 cubic feet of gas used in the longest night, 24th December. About 2500 persons are employed in the metropolis alone, in Uiis branch of manu- facture. Between 1822 and 1827 the quantity nearly doubled itself, and that in 5 years. Between 1827 and 1837 it doubled itself again. ITie consumption of coals of all kinds for the supply of gas to the metropolis during the year ending June, 1852, is almost exactly 408,000 tons, which on an average would yield al)out 4.000 millions of cubic feet of gas. GASHOLDER; a vessel for containing and preserving gas, of which various forms are described by chemical writers. GASOMETER, means properly a measurer of gas, though it is employed often to denote a recipient of gas of any kind. See the article Gas-Light. GAUZE WIRE CLOTH, is a textile fabric, either plane or tweeled, made of brass, iron, or copper wire, of very various degrees of fineness and openness of textureat Its chief uses are for sieves and safety lamps. GAY-LUSSITE, is a white mineral of a vitreous fracture, which crystallizes in oblique rhomboidal prisms; specific gravity from 1-93 to 1-95; scratches gvpsum, but is scratched by calcspar ; affords water by calcination ; it consists of carbonic acid 28-66; soda, 20 44; lime, 1770; water, 8220; clay, 100. It is in fact, by my ana- lysis, a hydrated soda-carbonate of lime in atomic proportions. This mineral occurs abundantly in insulated crystals, disseminated through the bed of clay which covers the nrao, or native sesquicarbonate of soda, at Lagunilla in Columbia. GELATINE ; (Eng. and Fr. ; Gallert, Leitn, Germ.) is an animal product which is never found in the humours, but it may be obtained by boiling with water the soft and solid parts; as the muscles, the skin, the cartilages, bones, ligaments, tendons, and mem- iM^nes. Isinglass consists almost entirely of gelatine. This substance is very soluble in boiling water; the solution forms a tremulous mass of jelly when it cools. Cold water has little action upon gelatine. Alcohol and tannin (tannic acid, see Gall-nuts) pre- cipitate gelatine from its solution; the former by abstracting the water, the latter by combining with the substance itself into an insoluble compound, of the nature of leather. No other acid, except the tannic, and no alkali, possesses the property of precipitating GELATINE. 895 gelatine. But chlorine and certain salts render its solution more or less turbid ; as the nitrate and bi-chloride of mercury, the proto-chloride of tin, and a few others. Sulphuric acid converts a solution of gelatine at a boiling heat into sugar. See Ligneous Fibee. Gelatine consists of carbon, 47*88 ; hydrogen, 7*91 ; oxygen, 27'21. See Glue and Isinglass. This substance is produced by boiling the skin of animals in water, which in its crude but solid state is called glv^, and when a tremulous semi-liquid, size. The latter preparation is greatly used by the paper-makers, and was much improved by the following process, for which Mr. William Rattray obtained a patent in May, 1838. The parings and scrows of skins are steeped in water till they begin to putrefy ; they are then washed repeatedly in fresh water with the aid of stampers, afterwards subjected, in wooden or leaden vessels, to the action of water strongly impregnated with sulphurous acid for from 12 to 24 hours; they are now drained, washed with stampers in cold water, and next washed with water of the temperature of 120° F., which is poured upon them and run off very soon to complete their purification. The scrows are finally con- verted into size, by digestion in water of 120° for 24 hours; and the solution is made perfectly fine by being strained through several thicknesses of woollen cloth. They must be exhausted of their gelatinous substance, by repeated digestions in the warm water. The claim is for the sulphurous acid which, while it cleanses, acts as an antiseptic. — Netoton^s Journal, xiv. 173. A fine gelatine for culinary uses, as a substitute for isinglass, is prepared by Mr. Nelson's patent, dated March, 1839. After washing the Darings, Apeticl GERMAN SILVER. See the latter end of the article Copper. GERMINATION; (Eng. and Fr.; Das Keimen, Germ.) is the first sprouting of a seed after it is sown, or when, after steeping, it is spread upon the malt floor. See Beer. GIG MACHINES, are rotatory drums, mounted with thistles or wire teeth for teazling cloth. See Woollen Manufacture. GILDING [Dorure, Fr. ; Vergoldung, Germ.) ; is the art of coating surfaces with a thin film of gold. For a full discussion of this subject, see Gold. Mr. Elkingttm, gilt toy maker, obtained a patent, in June, 1836, for gilding copper, brass, 0 minutes longer, skimming it the whole time. Then add the thin rinds of 50 lemons boiling them lo minutes more. Cut 28 lbs. of good Malaga raisins in half, take away the stones and stalks, and put them, with the juice of the lemon, strained, into the ho«^s- head- Strain the hot liquor into a cooler, and when it has stood two hours and"*!* settled, draw it off the lees, clear, and put it into the cask ; filter the thick and fill up with it. Leave the bung out, and when at the proper temperature stir 3 quarts ^/ *'"S.^^.^'*''^' ale yeast well into it; put on the bung lightly, and let it ferment 6 or 1 days, filling up with liquor as it ferments over. When the fermentation has ceased pour in 6 quarts of French brandy, and 8 ounces of the best isinglass, dissolved in a gallon of the wine; then secure the bung effectually, and paste paper over it, Ac Keep it « years in a cool cellar, then bottle it, using the best corks, and sealing them • and when it is 4 years old commence using it. ' GINNING, is the name of the operation by which the filaments of cotton are separable from the seeds. See Cottox Manufactuee. GLANCE COAL, or anthracite, of which there are two varieties, the slaty and the cotichmdaJ. See Anthuacitk and Pitcoal. GLASS {Verre, Fr. ; Glas, Germ.); is a transparent solid formed by the fusion of siliceous ami alkaline matter. It was known to the Phoenicians, and constituted for a long time an exclusive manufacture of that people, in consequence of its ingredients natron, sand, and fuel, abounding upon their coasts. It is probable that the more ancient Egyptians were unacquainted with glass, for we find no mention of it in the writings of Moses. But according to Pliuy and Strabo, the glass works of Sidon and Alexandria were famous in their times, and produced beautiful articles, which were cut, engraved, gilt, and stained of the most brilliant colours, in imitation of precious stones. The Romans employed glass for various purposes; and have left specimen* in Herculaneura of window-glass, which must have been blown by methods analo^-ous to ^ GLASS. GLASS-MAKING. 901 the modem. The Phoenician processes seem to have been learned by the Crusaders, and transferred to Venice in the 13th century, where they were long lield secret, and formed a lucrative commercial monopoly. Soon after the middle of the 17th century, Colbert enriched France with the blown mirror glass manufacture. Chance undoubtedly had a principal share in the invention of this curious fabrication, but there were circumstances in the most ancient arts likely to lead to it ; such as the fusing and vitrifying beats required for the formation of pottery, and for the extraction of metals from their ores. Pliny ascribes the origin of glass to the following accident. A merchant ship lad^D with natron being driven upon the coast at the mouth of the river Belus, in tempestuous weather, the crew were compelled to cook their victuals ashore, and having placed lumps of the natron upon the sand, as supports to the kettles, found to their surprise masses of transparent stone among the cinders. The sand of this small stream of Galilee, which runs from the foot of Mount Carmel, was in consequence sup- poseil to possess a peculiar virtue for making glass, and continued for ages to be sought after and exported to distant countries for this purpose. Agricola, the oldest author who has written technically upon glass, describes furnaces and processes closely resembling those employed at the present day. Neri, Kunckel, Henckel, Pott, Achard, and some other chemists, have since then composed treatises upon the subject ; but Neri, Bosc, Antic, Loysel, and Allut, in the Encyclopedia Methodique, are the best of the older authorities. The wmdow-glass manufacture was first begun in England in 1557, in Crutched Friars, London ; and fine articles of flint-glass were soon afterwards made in the Savoy House, Strand. In 1635 the art received a great improvement from Sir Robert Mansell, by the use of coal fuel instead of wood. The first sheets of blown glass for looking-glasses and coach windows were made in 1673 at Lambeth, by Venetian artisans employed under the patronage of the Duke of Buckingham. The casting of mirror-plates was commenced in France about the year 1688, by Abraham Thevart ; an invention which gave rise soon afterwards to the establishment of the celebrated works of St. Gt)bain, which continued for nearly a century the sole place where this highly-prized object of luxury was well made. In cheapness, if not in excel- lence, the French mirror-plate has been for gome time rivalled by the English. The analysis of modern chemists, which will be detailed in the course of this article, and the light thrown upon the manufacture of glass in general by the accurate means now possessed of purifying its several ingredients, would have brought the art long since to the highest state of perfection in this country, but for the vexatious interference and obstructions of our excise laws. The researclies of Berzelius having removed all doubts concerning the acia character of silica, the general composition of glass presents now no difficulty of conception. This substance consists of one or more salts, whicli are silicates with bases of potash, Hoda, lime, oxide of iron, alumina, or oxide of lead ; in any of which compounds we can substitute one of these bases for another, provided that one alkaline base be left. Silica in its turn may be replaced by the boracic acid, without causing the glass to lose ita principal characters. Under the title glass are therefore comprehended various substances fusible at a high temperature, solid at ordinary temperatures, brilliant, generally more or less transparent, and always brittle. The following chemical distribution of glasses lias been proposed. 1. Soluble glass; a simple silicate of potash or soda; or both of these alkalis. 2. Bohemian or crown glass ; silicate of potash and lime. 3. Common window and mirror glass •. silicate of soda and lime ; sometimes also of potash. 4. Bottle glass ; silicate of soda, lime, Alumina and iron. 5. Ordinary crystal glass ; silicate of potash and lead. 6. Flint glass ; silicate of potash and lead ; richer in lead than the preceding. 7. Strass ; silicate of potash and lead ; still richer in lead. 8. Enamel ; silicate and stannate or antimoniate of potash or soda, and lead The glasses which contain several bases are liable to suffer different changes when they are n:elted or cooled slowly. The silica is divided among these bases, forming new compounds in definite proportions, which by crystallizing separate from each other, so that the general mixture of the ingredients which constitute the glass is destroyed. It becomes then very hard, fibrous, opaque, much less fusible, a better conductor of electri- city and of heat ; forming what Reaumur styled devitrijied glass ; and what is called after him Reaumur's porcelain. This altered glass can always be produced in a more or less perfect »«tate, by melting the glass and allowing it to cool very slowly ; or merely by heating it to the softening pitch, and keeping it at this heat for some time. The process succeeds best with the most complex vitreous compounds, such as bottle glass ; next with ordinary window glass ; and lastly with glass of potash and lead. This property ought to be kept constantly in view in manufacturing glass. It shows why m making bottles we should fashion them as quickly as possible with the aid of a mould and reheat them as seldom as may be absolutely necessary. If it be often heated and cooled, the glass loses its ductility, becomes refractory, and exhibits a multitude of stony granulations throughout its substance. When coarse glass is worked at the enamel- ler 8 lamp, it is apt to change its nature in the same way, if the workman be not quick and expert at his business. From these facts we perceive the importance of making a careful choice of the glass mtended to be worked in considerable masses, such as the large object glasses of tele- scopes; as their annealing requires a very slow process of refrigeration, which is apt to cause devitrified specks and clouds. For such purposes, therefore, no other species of glass 18 well adapted except that with basis of potash and lead ; or that with basis of potash and lime. These two form the best flint glass, and crown glass ; and they «:hould be exclusively employed for the construction of the object glasses of achromatic telescopes. Crystal glass is rapidly corroded by the sulphate of ammonia at a heat of 600° Fahr. The following is an account of the exports of British manufacture : Flint glass cwts. Window glass cwts. Bottles, green or common - cwts. Plate glass value Quantities. 1851. 23,870 15,517 296,065 1852. 25,755 16,460 825,804 Declared Value. 1851. 1852. £106,500 20,077 162,843 18,335 £110,519 22,234 172,880 20,929 Imports and exports of Glass of Foreign and Colonial produce in the years endino- respectively 5th January, 1851 and 1852:— ^ o Window glass, not exceeding \ of an inch thick, and shades and cylinders : imports ?l'^l? '"'^i^; ol"il ^^'^^^ ^'^^•' ^*P°^^^' ^^'604 c^*s. and 2,059 cwta; duty on imports! 1,656/. and 1,877/. r ~» All glass exceeding » of an inch thick, all silvered or polished glass of whatever thick- ness: imports, 122,394 sq. ft. and 173,935 sq. ft.; exports, 32,388 sq. ft and 36.550 sq. ft. ; duty received, 1,845/. and 2,841/. ' i » " ^..^^'^')*^fJo*.n^lf ^ ^"^^ ^^^''^^}. ^''*^^^') "^* ^'^*' engraved, or otherwise ornamented: lof/'Tnd 108/ '^^^ ' ^''^'■*'' '^^'^^^ ^^'' ^""^ ^^'^^^ ^^'- ' ^"*y ^^<^^'^^ed, 11 ^^^ ^J"lol'n,^^^?u' ^'°^ coloured glass, and fancy ornamental glass: imports, 880,981 and4''454/ ' ' ^^^'^'' ^^^'^^^ ^^'' ^"^ ^^^'^^^ lbs. ; duty received, 5,542/. GLASS-MAKING, general principles of. Glass may be defined in technical phrase- ology, to be a transparent homogeneous compound formed by the fusion of silit^ with oxides of the alkaline earthy, or common metals. It is usually colourless, and then resembles rock crystal, but is occasionally stained by accident or design with coloured metallic oxides. At common temperatures it is hard and brittle, in thick pieces • in thin plaesor threads, flexible and elastic; sonorous when struck; fracture conchoidal and of that peculiar lustre called vitreous; at a red heat, becoming soft, ductile and plastia Besides glass properly so called, other bodies are capable of entlring into vitreous fusio^ as phosphoric acid boracic acid, arsenic acid, as also certain metaUic oxides, as of lead an. antimony, and several chlorides; some of which are denominated glasses Impure and opaque v. triform masses are called slags; such are the production Sf blast iron fur! naces and many metallurgic operations. Silica, formerly styled the earth of flints, which constitutes the basis of all commercial g^ass, •« 'nfusib^ by itself in the strongest fire of our furnaces; but its vitreous fusLnts cas y eff-ected by a competent addition of potash or soda, either alone or mixed with lime >Lo« nTfr. if fr- ' "i Tx!"^ ^u ^^•g^r^^d ^ belonging to the class of acids, com- be eu J L'l'^^ f"T ""f- *^'''. ^''.''' ^?^^, '^^'''^ compounds ; and hence glasL may be Mewed as a silicate of certain oxides, m which the acid and the bases exist in equiva- ZJr\T T"- .^T ^^^«^P'•«P«[t.«°^. or the quantities of the bases which silica ZVnZJ'Vr' «^*"'-fV,''\''\*''^ "'^^•'°- P^^"*' "^^*^^l3^ ascertained, we micrht readily determine beforehand the best proportions of materials for the glass manufacture. But nf .^ nrt. ^''7,,^'"^.^'^^ «^!«' «"^ as it is, moreover, not improbable that the capacity of saturation of^he silica varies with the temperature, and that the properties of gla4 also vary with the bases, we must, in the present state of our knowlldge. regulate the proportions rather by practice than by theory, though the latter may throw an indirect ight upon the subject. For example, a good colourless glass has been found by analysU to consist of 72 parts of silica, 13 parts of potash, and 10 parts of lime, in 95 parts. If we reduce these numbers to the equivalent ratios, we shall have the followii^ results- taking the atomic weights as given by Berzelius. * 902 GLASS-MAKING. GLASS-MAKING. M» 1 atom potash = 590 14.67 1 lime 356 8-84 > 3 silica 1722 42-79 S 2 silica 1155 28-70 ) is soda ; for potash does not assimilate well with the calcareous 571-49 3823 95-00 This glass would therefore have been probably better compounded with the just atomic proportions, to which it nearly approaches, viz. 71*49 silica, 14*67 potash, and 8*84 lime, instead of those given above as its actual constituents. The proportions in which silica unites with the alkaline and other oxydes are mo- dified by the temperature as above stated ; the lower the heat, the less silica will enter into the glass, and the more of the base will in general be required. If a glass which contains an excess of alkali be exposed to a much higher temperature than thai of ils formation, a portion of the base will be set free to act upon the materials of the earthen pot, or to be dissipated in fumes, until such a silicate remains as to constitute a per- manent glass corresponding to that temperature. Hence the same mixture of vitrifiable materials will yield very different results, according to the heats in which it is fused and worked in the glass-house ; and therefore the composition should always be referrible to the going of the furnace. When a species of glass which at a high temperature formed a transparent combination with a considerable quantity of lime, is kept for some time in fusion at a lower temperature, a portion of the lime unites with the silica into another combination of a semi-vitreous or even of a stony aspect, so as to spoil the transparency of the glass altogether. There is probably a supersilicate and a sub-silicate formed in such cases ; the latter being much the more fusible of the two compounds. The Reau- mur's porcelain produced by exposing bottle glass to a red heat for 24 hours, is an exam- ple of this species of vitreous change, in which new affinities are exercised at a lower temperature. An excess of silica, caused by the volatilization of alkaline matter with too strong firing, will bring on similar appearances. The specific gravity of glass varies from 2-3 to 3'6. That of least specific gravity con- sists of merely silica and potash fused together ; that with lime is somewhat denser, and with oxyde of lead denser still. Plate glass made from silica, soda, and lime, has a speci- fic gravity which varies from 2*50 to 2*6 ; crystal or flint glass from 3*0 to 3*6. The power of glass to resist the action of water, alkalis, acids, air, and light, is in general the greater, the higher the temperature employed in its manufacture, the smallei the proportion of its fluxes, and the more exact the equivalent ratios of its constituents. When glass contains too much alkali, it is partially soluble in water. Most crystal glass is aflected by having water boiled in it for a considerable time ; but crown glass being poorer in alkali, and containing no lead, resists that action much longer, and is therefore better adapted to chemical operations. The affinity of glass for water, or its hygrometric attraction, is also proportional to the quantity of alkali which it contains. In general also potash glass is more apt to become damp than soda glass, agreeably to the respective hygrometric properties of these two alkalis, and also to the smaller proportion of soda than of potash requisite to form glass. Air and light operate upon glass probably by their oxydizing property. Bluish or greenish colored glasses become by exposure colorless, in consequence undoubt- edly of the peroxydizement of the iron, to whose protoxyde they owe their tint; other glasses become purple red from the peroxydizement of the manganese. The glasses which contain lead, suffer another kind of change in the air, if sulphureted hydrogen be present ; the oxyde of lead is converted into a sulphuret, with the efl'ect of rendering the surface of the glass opaque and iridescent. The more lead is in the glass, the quicker does this iridescence supervene. By boiling concentrated sulphuric acid in a glass vessel, or upon glass, we can ascertain its power of resisting ordinary men- strua. Good glass will remain smooth and transparent ; bad glass will become rough and dim. The brittleness of unannealed glass by change of temperature is sometimes very great. I have known a thick vessel to fly by vicissitudes of the atmosphere alone. This defect may be corrected by slowly heating the vessel in salt water or oil to the highest pitch consistent with the nature of these liquids, and letting it cool very slowly. Within the limits of that range of heat, it will, in consequence of this treatment, bear alternations of temperature without cracking as before. It has been said that glass made from silica and alkalis alone will not resist the action of water but that the addition of a little lime is necessary for this effect. In general 100 parts of quartzose sand require 33 parts of dry carbonate of soda for their vitrifica- tion, and 45 parts of dry carbonate of potash. But to make unchangeable alkaline glass, especially with potash, a smaller quantity of this than the above should be used, with a very violent heat. A small proportion of lime increases the density, hardness, and lustre of glass ; and it aids in decomposing the alkaline sulphates and muriates always present in the pearlash of commerce. From 7 to 20 parts of dry slaked lime have been added Tx 100 of silica, with advantge, it is said, ia some German glass manufactories, where the alkaline matter earth. In many glass works on the Continent, sulphate of soda is the form ander which alkaline matter is introduced into glass. This salt requires the addition of 8 per cent, of char- coal to decompose and dissipate its acid; a result which takes place at a high heat, with- out the addition of any lime. 88 pounds of quartz-sand, 44 pounds of dry glauber salt, and 3 pounds of charcoal, properly mixed and fused, afford a limpid, fluent, and workable g ass ; with the addition of 17 pounds of lime, these materials fuse more readily into a plastic mass. If less carbon be added, the fusion becomes more tedious. The two follow- ing formulae afford good glauber salt glass. L 2. Sand .... Calcined sulphate of soda Lime .... Charcoal - . - - ^ y,^ *,, The first mixture has been proved in the looking-glass manufactory of Ncthaus near Vienna, and the second by the experiments of Kirn. The fusion of the first requires 1^, of the second 21 hours. The bluish green tinge which these otherwise beautiful and brilliant glasses possess, is not removeable by the ordinary means, such as mano-anese or arsenic which decolor alkaline glass. When the sulphate of soda and charcoaf are used in smaller proportions, the glass becomes more colorless. The tinge is no doubt owing to the sulphur combining with the oxyde of sodium, in some such way as in the pismenl ultramarine. y s ^"^ By a proper addition of galena (the native sulphuret of lead), to glauber salt and quarts sand, without charcoal, it is said a tolerably good crystal glass may be formed. The sulphuric acid of the salt is probably converted by the reaction of the sulphuret of lead into sulphurous acid gas, which is disengaged. One atom of sulphuret of lead = 1495-67, is requisite to decompose 3 atoms of sulphate oi soda = 2676. It is stated, on good authority, that a j?ood colorless glass may be ob- tamed by using glauber salt without charcoal, as by the following formula. Quartz-sand - - - - 100 pounds Calcined glauber salt - - 24 Lime 20 Cullet of soda glass - - 12 The melting heat must be continued for 26| hours. A small quantity of the sand is reserved to be thrown in towards the conclusion of the process, in order to facilitate the expulsion of air bubbles. The above mixture will bear to be blanched by the addition of raansanese and arsenic. The decomposition of the salt is in this case effected by the hme, with wi>!ch the sulphuric acid first combines, is then converted into sulphurous acid, and dissipated. Glass made m this way was found by analysis to consist of 79 parts of saica, 12 lime, and 9-6 soda, without any trace of gypsum or sulphuric acid Glauber salt is partially volatilized by the heat of the furnace, and acts upon the arch of the oven and the tops of the pots. This is best prevented by introducing at first into the pots the whole of the salt mixed with the charcoal, the lime, and one fourth part of the sand ; fusing this mixture at a moderate heat, and adding gradually afterwards the remainder of the sand, mcreasing the temperature at the same time. If we put in the whole ingredients together, as is done with potash glass, the sand and lime soon fall to the bottom, while the salt rises to the surface, and the combination becomes difficult and UucQ ufllJ • Sulphate of potash acts in the same way as sulphate of soda Muriate of soda also, according to Kirn, may be used as a glass flux with advantage. H^Z^mI /";^^^^^,P^°P«rt.ons are 4 parts of potash, 2 of common salt, and 3 of l^e. agreeably to the following compositions : * L 2. Quartz-sand ... Calcined carbonate of potash Common salt • • . Lime . • '. . For No. L, the melting heat must be 10 hours, whicli'turns out a very pure, '^iTd. good gla^s; for No 2., 23 hours of the furnace are required. Instead of the potash, glkuber salt may be substituted ; the proportions being then 19-1 glauber salt, 9-5 muriate of soda. 14-3 lime, 7 51 sand, and 1-3 charcoal * The oxide of lead is an essential constituent of the denser glasses, and may be regarded as replacing the lime, so as to form with the quartz-sand a silicate of lead. It assimilates best with purifaed pearl ash, on account of the freedom of this alkali from iron which ia present m most sodas. ' " 904 GLAS». GLASS-MAKING. 905 Its atomic constitution may be represented as follows : — I I i« Silicic acid Oxide of lead . - - - • Potash Oxides of iron and manglmese 5 atoms = 28'77* 1 = 1394-5 1 = 690-0 Gompatation. Analysis. 59-19 28-68 12-13 59-20 28.20 9-00 1-40 4861-6 100-00 100-00 The above analysis by Berthier relates to a specimen of the best English crystal glass, perfectly colourless and free from air-bubbles. This kind of glass may however take several different proportions of potash and silica to the oxide of lead. The composition of mirror-plate, as made on the Continent, is as follows : — White quartz- sand ----- 300 pounds Dry carbonate of soda - - - - - 100 Lime slaked in the air - - - - - 48 Gullet, or old glass - - - • • 800 The manganese should not exceed one-half per cent, of the weight of soda. Optical glass requires to be made with very peculiar care. It is of two different kinds; namely, crown glass a.ndjlint glass. The latter contains a considerable proportion of lead, in order to give it an increased dispersive power upon the rays of light, in proportion to its mean refractive power. Optical crown glass should be perfectly limpid, and have so little colour, that a pretty thick piece of it may give no appreciable tinge to the rays of light. It should be exempt from striae or veins as well as air-bubbles, and have not the slightest degree of milkiness. It should moreover preserve these qualities when worked in considerable quantities. Potash is preferable to soda for making optical crown glass, because the latter alkali is apt to make a glass which devitrifies and becomes opalescent, by long exposure to heat in the annealing process. A simple potash silicate would be free from this defect, but it would be too attractive of moisture, and apt to decompose eventually by the humidity of the atmosphere. It should therefore contain a small quantity of lime, and as little potash as suffices for making a perfect glass at a pretty high temperature. It is probably owing to the high heats used in the English crown glass works, and the moderate quantity of alkali (soda) which is employed, that our crown glass has been found to answer so well for optical purposes. The following recipe for crown glass is excellent : — 5 atoms of silica (2^ ?) - - - - 80 1 carbonate of soda - - - - - 54 5 silica - - - - - - 80 1 carbonate of lime - - - - - 50 1 atom of carbonate of baryta - - - 98 5 atoms of silica - - - - - 80 Silicates of lime and baryta per se, or even combmed, are very refractory ; but they vitrify well along with a third silicate, such as that of soda, or potash. Practical Details of the Manufacture of Glass, The Venetians were the first in modern times who attained to any degree of excellence in the art of working glass, but the French became eventually so zealous of rivalling them, particularly in the construction of mirrors, that a decree was issued by the court of France, declaring not only that the manufacture of glass should not derogate from the dignity of a nobleman, but that nobles alone should be masters of glass-works. Within the last 30 or forty years, Great Britain has made rapid advances in this important art, and at the present day her pre-eminence in every department hardly admits of dispute. There are five different species of glass, each requiring a peculiar mode of fabrication, and peculiar materials : 1. The coarsest and simplest form of this manufacture is bottle glass. 2. Next to it in cheapness of material may be ranked broad or spread window glass. An improved article of this kind is now made near Birmingham, under the name of British or German plate. 3. Crown glass comes next, or window glass, formed in large circular plates or discs. This glass is peculiar to Great Britain. 4. Flint glasf, crystal glass, or glass of lead. 5. Plate or fine mirror glass. The materials of every kind of glass are vitrified in pots made of a pure refractory day ; the best kind of which is a species of shale or slate clay dug out of the coal-form- ation near Stourbridge. It contains hardly any lime or iron, and consists of silica and alumina in nearly equal proportions. The masses are carefully picked, brushed; and ground under edge iron wheels of considerable weight, and siAed through sieves having 20 meshes in the square inch. This powder is moistened with water (best hot), and kneaded by the feet or a loam-mill into a uniform smooth paste. A large body of this (lough should be made up at a time, and laid by in a damp cellar to ripen. Pre- viously to working it into shapes, it should be mixed with about a fourth of its weight of cement of old pots, ground to powder. This mixture is sufficiently plastic, and being less contractile by heat, forms more solid and durable vessels. Glass-house pots have the figure of a truncated cone, with the narrow end undermost ; those for bottle and window-glass being open at top, about 30 inches diameter at bottom, 40 inches at the mouth, and 40 inches deep; but the flint-glass pots are covered in at top with a dome-cap, having a mouth at the side, by which the materials are introduced, and the glass is ex- tracted. Bottle and crown-house pots are from 3 to 4 inches thick ; those for flint-houses are an inch thinner, and of proportionally smaller capacity. The well-mixed and kneaded dough is first worked upon a board intc t cake for the bottom ; over this the sides are raised, by laying on its edges rolls of clay above each other with much manual labor, and careful condensation. The clay is made into lumps, is equalized, and slapped much in the same way as for making Pottery. The pots thus fashioned must be dried very prudently, first in the atmospheric temperature, and finally in a stove floor, which usually borrows its heat directly from the glass-house. Before setting the pots in the furnace, they are annealed during 4 or 5 days, at a red heat, in a small reverberalory vault, made on purpose. When completely annealed, they are transferred with the utmost expedition into their seat in the fire, by means of powerful tongs supported on the axle of an iron-wheel carriage frame, and terminating in a long lever for raising them and swinging them round. The pot-setting is a desperate service, and when unskilfully conducted without due mechanical aids, is the forlorn hope of the glass-founder. — Quceque ipse miserrima vidi. The celebrated chemist. Dr. Irvine, caught his last illness by assisting imprudently at this formidable operation. The working breast of the hot furnace must be laid bare so as to open a breach for the extraction of the faulty pot, and the insertion of the fresh one, both in a stale of bright incandescence. It is frightful to witness the eyes an^ fuming visages of the workmen, with the blackening and smoking of their scorched wool- len clothes, exposed so long to the direct radiations of the flame. A light mask and sack dress coated with tinfoil, would protect both their faces and persons from any annoyance, at a very cheap rate. The glass-houses are usually built in the form of a cone, from 60 to 100 feet high, and from 50 to 80 feet in diameter at the base. The furnace is constructed in the centre of the area, above an arched or groined gallery which extends across the whole space, and terminates without the walls, in large folding doors. This cavern must be sufficiently high to allow laborers to wheel out the cinders in their barrows. The middle of the vaulted top is left open in the building, and is covered over with the grate-bars of the furnace. 1. Bottle glass. — The bottle-house and its furnace resemble nearly yig. 505. The fur- nace is usually an oblong square chamber, built of large fire-bricks, and arched over with fire-stone, a silicious grit of excellent quality extracted from the coal measures of New- castle. This furnace stands in the middle of the area; and has its base divided into three compartments. The central space is occupied by the grate-bars ; and on either side is the platform or fire-brick siege (seat), raised about 12 inches above the level of the ribs upon which the pots rest. Each siege is about 3 feet broad. In the sides of the furnace, semi-circular holes of about a foot diameter are left oppo- site to, and a little above the top of. each pot, called working holes, by which the work- men shovel in the materials, and take out the plastic glass. At each angle of the furnace there is likewise a hole of about the same size, which communicates with the calcining furnace of a cylindrical form, dome-shaped at top. The flame that escapes from the found- ing or pot-furnace is thus economically brought to reverberate on the raw materials of the bol tie-glass, so as to dissipate their carbonaceous or volatile impurities, and convert them into a frit. A bottle-house has generally eight other furnaces or fire-arches ; of which six are used for annealing the bottles after they are blown, and two for annealing the pots, before setting them in the furnace. The laws of this country till lately prohibited the use for makmg common bottled of any fine materials. Nothing but the common river sand, and soap-boilers' waste, was allowed. About 3 parts of waste, consisting of the insoluble residuum of kelp, mixed with lime and a little saline substance, were used for 1 part of sand. This waste was first of all calcined in two of the fire arches or reverberatories reserved for that purpose, called the coarse arches, where it was kept at a red heat, with occasional stirring, from 24 to 30 hours, being the period of a journey or joumce, in which the materials could be melted and worked into bottles. The roasted soap-waste was then withdrawn, under the name of ashes, from its arch, coarsely ground, and mixed with its proper proportion of sand. This mixture was now put into the fine arch, and calcined during the working jour- ney, which extended to 10 or 12 hours. Whenever the pots were worked out, tnat frit M i| 906 GLASS-MAKING. was immediately transferred into them in its ignited state, and the founding process proceed* d with such despatch that this first charge of materials was completely melted down in 6 hours, so that the pots might admit to be filled up again with the second charge of frit, which was founded in 4 hours more. The heat was briskly continued, and in the course of from 12 to 18 hours, according to the size of the pots, the quality of the fuel, and the draught of the furnace, the vitrification was complete. Before blowing the bottles, however, the glass must be left to settle, and to cool down to the blowing con- sistency, by shutting the care doors and feeding holes, so as to exclude the air from the fire-grate and the bottom of the hearth. The glass or metal becomes more dense, and by its subsidence throws up the foreign lighter earthy and saline matters in the form of a scum on the surface, which is removed with skimming irons. The furnace is now charged with coal, to enable it to afford a working heal for 4 or 5 hours, at the end of which time more fuel is cautiously added, to preserve adequate heat for finishing the journey. It is hardly possible to convey in words alone a correct idea of the manipulations neces- sary to the formation of a wine bottle ; but as the manufacturers make no mystery of this matter, any person may have an opportunity of inspecting the operation. Six people are employed at this task ; one, called a gatherer, dips the end of an iron tube, about five feet long, previously made red-hot, into the pot of melted metal^ turns the rod round so as to surround it with glass, lifts it out to cool a little, and then dips and turns it round again ; and so in succession till a ball is formed on its end sufficient to make the required bottle. He then hands it to the blower, who rolls the plastic lump of glass on a smooth stone or cast-iron plate, till he brings it to the very end of the tube ; he next introduces the pear-shaped ball into an open brass or cast-iron mould, shuts this together by pressing a pedal with his foot, and holding his tube vertically, blows through it, so as to expand the cooling glass into the form of the mould. Whenever he takes his foot from the pedal-lever, the mould spontaneously opens out into two halves, and falls asunder by its bottom hinge. He then lifts the bottle up at the end of the rod, and transfers it to the finisher, who, touching the glass tube at the end of the pipe with a cold iron, cracks off the bottle smoothly at its mouth-ring. The finished bottles are immediately piled up in the hot an- nealing arch, where they are afterwards allowed to cool slowly for 24 hours at least. See Bottle Mould. 2. Broad or spread vnndow-glass. — This kind of glass is called inferior window-glass, in this country, because coarse in texture, of a wavy wrinkled surface, and very cheap, but on the Continent spread window-glass, being made with more care, is much better than ours, though still far inferior in transparency and polish to crown glass, which has, therefore, nearly superseded its use among us. But Messrs. Chance and Hartley, of West Bromwich near Birmingham, have of late years mounted a spread-glass work, where they make British sheet glass, upon the best principles, and turn out an ar- ticle quite equal, if not superior, to anything of the kind made either in France or Bel- gium. Their materials are those used in the crown-glass manufacture. The vitrifying mixture is fritted for 20 or 30 hours in a reverberatory arch, with considerable stirring and puddling with long-handled shovels and rakes ; and the frit is then transferred by shovels, while red hot, to the melting pots to be founded. When the glass is rightly vitrified, settled, and brought to a working heat, it is lifted out by iron tubes, as will be described under the article Crown Glass, blown into pears, which being elongated into cylinders, are cracked up along one side, parallel to the axis, by touching them with a cold iron dipped in water, and are then opened out into sheets. Glass cylinders are spread in France, and at West Bromwich, on a bed of smooth stone Paris-plaster, or laid on the bottom of a reverberatory arch; the cylinder being placed on its side horizontally, with the cracked line uppermost, gradually opens out, and flattens on the hearth. At one time, thick plates were thus prepared for subsequent polishing into mir- rors ; but the glass was never of very good quality ; and this mode of making mirror-plate has accordingly been generally abandoned. The spreading furnace or oven is that in which cylinders are expanded into tables or plates. It ought to be maintained at a brisk red heat, to facilitate the softening of the glass. The oven is placed in immediate connexion with the annealing arch, so that the tables may be readily and safely transferred from the former to the latter. Sometimes the cylinders are spread in a large muffle furnace, in order to protect them from being tarnished by sulphureous and carbonaceous fumes. Fig. 709 represents a ground plan of both the spreading and annealing furnace ; Jig. •710 is an oblong profile in the direction of the dotted line x x^fig. 709. a is the fire-place ; 6 6 the canals or flues through which the flame rises into both furnaces; c the spreading furnace, upon whose sole is the spreading slab, d is the cool- ing and annealing oven ; e e iron bars which extend obliquely across the annealing arch, and serve for resting the glass tables against, during the cooling. / / the channel ■long which the previously cracked cylinders are slid, so as to be gradually warmed { GLASS-MAKING. 907 g the opening .-i the spreading furnace, for enabling the workmen to regulate the pro- cess ; h a door in the annealing arch, for introducing the tools requisite for raising uf and removing the tables. In forming glass-plates by the extension of a cylinder into a plane, the workman first blows the lump of glass into the shape of an oblong pear, the length of which must be nearly equal to the length of the intended plate, and its diameter such, that the circum- ference, when developed, will be equal to the breadth of the plate. He now rests the blowing iron on a stool or iron bar, while an assistant, with a pointed iron, pierces a hole into the extreme end of the pear, in the line of the blowing-pipe. This opening is then enlarged, by introducing the blade of a pair of spring-tongs, while the glass is turned round; and by skilful management, the end of the pear is eventually opened out into a cylindrical mouth. The workman next mounts upon a stool, and holds the blowing-iron perpendicularly. The blown cylinder is now cracked off, a punto rod of iron having been previously stuck to its one end, to form a spindle for working the other by. This rod has a flai disc on its end, or three prongs, which being dipped in melted glass, are applied to the mouth of the cylinder. By this as a handle, the glass cone is carried to the fire, and the narrow end being heated, is next opened by spring tongs, and formed into a cylinder of the same size as the other end. The cylinder, thus equalized, is next cracked or slit down in its side with a pair of shears, laid on a smooth copper plate, detached from the iron rod, spread out by heal into a plane surface, and finally annealed. This series of transformations is represented in fig. 711, at a, b, c, d, e, f, g, h. Figs. 712 and 713 represent a Bohemian furnace in which excellent white window glass is founded. Fig. 712 is a longitudinal section of the glass and annealing furnace. Fig. 713 is the ground plan, a is the ash-pit vaulted under the sole of the furnace ; the fire-place itself is divided into three compartments ; with a middle slab at «"« ^ 5. Plate glass. This, like English crown-glass, has a soda flux; whereas flint-glass requires potash and is never of good quality when made with soda. We shall distribute our account of this manufacture under two heads. 1. The different furnaces and principal machines, without whose knowledge it would be impossible to understand the several processes of a plate-glass factory. 2. The materials which enter into the composition of this kind of glass, and the series of operations which they undergo; devoting our chief attention to the changes and im- provements which long experience, enlightened by modern chemistry, has introduced into the great manufactory of Saint-Gobin, in France, under the direction of M. Tassaert It may however be remarked, that the English plate-glass manufacture derives peculiar advantages from the excellence of its grinding and polishing machinery. The clay for making the bricks and pots should be free from lime and iron, and very refractor)'. It is mixed wilh the powder of old pots passed through a silk sieve. If the clay be very plastic it will bear ils own weight of the powder, but if shorter in quality. It will take only three fifths. But before mingling it with the cement of old pots, it must be dried, bruised, then picked, ground, and finally elutriated by agitation with water decantation through a hair sieve, and subsidence. The clay fluid after passing the sieve IS called slip (coulis). The furnace is built of dry bricks, cemented with slip, and has at each of its four angles a peculiar annealing arch, which communicates with the furnace interiorly, and thence derives suflicient heat to effect 'in part, if not wholly, the annealing of the pots which are always deposited there a long time before they are used. Three of these arches, exclusively appropriated to this purpose, are called pot-arches. The fourth is called the arcA of ihe materials, because it serves for drying them before they are founded, tach arch has, moreover, a principal opening called the throat, another called bonnard, by the French workmen, through which fire may be kindled in the arch itself, when it was thought to be necessary for the annealing of the pots ; a practice now abandoned. Ihe duration of a furnace is commonly a year, or at most 14 months ; that of the arches IS 30 years or upwards, as they are not exposed to so strong a heal. In the manufacture of plate-glass two sorts of crucibles are employed, called the pots and the basins (cuvettes). The first serve for containing the materials to be founded, and for keeping them a long time in the melted state. The cuvettes receive the melted glass after it is refined, and decant it out on the table to be rolled into a plate. Three pots hold liquid glass for six small basins, or for three large ones, the latter bein^ employed for making mirrors of great dimensions, that is, 100 inches long and up. GLASS-MAKING. 915 wards. Furnaces have been lately constructed with 6 pots, and 12 cuvettes, 8 of which are small, and 4 large; and cuvettes of three sizes are made, called small, middling, and large. The small are perfect cubes, the middling and the large ones are obh.ng parallel opipeds. Towards the middle of their height, a notch or groove, two or three inches broad, and an inch deep, is left, called the girdle of the cuvette, by which part they are grasped with the tongs, or rather are clamped in the iron frame. This frame goes round the four sides of the small cuvettes, and may be placed indifferently upon all their sides; in the other cuvettes, the girdle extends only over the two large sides, because they cau- not be turned up. See m T,Jig. 724, p. 918. The pot is an inverted truncated cone, like a crown glass pot. It is about 30 inches high, and from 30 to 32 inches wide, including its thickness. There are only a few inches of diflerence between the diameter of the top and that of vhe bottom. The bottom is 3 inches thick, and ihe body turns gradually thinner till it is an inch at the mouth of the pot. The large building or factory, of which the melting furnace occupies the middle space, IS called the halle in French. At Ravenhead in Lancashire it is called the foundry, and is of magnificent dimensions, being probably the largest apartment under one roof 'm Great Britain, since ils length is 339 feel, and ils breadth 155. The famous halle of Si. Gobin IS 174 feet by 120. Along the two side walls of the halky which are solidly con- structed of hewn stone, there are openings like those of common ovens. These ovens^ destined for the annealing of the newly cast plates, bear the name of carquaises. Their soles are raised two feet and a half above the level of the ground, in order to bring then into the same horizontal plane with the casting tables. Their length, amounting some- times to 30 feet, and their breadth to 20, are required in order to accommodate 6, 8, or even 10 plates of glass, alongside of each other. The front aperture is called the throat, and the back door the little throat (gueulette). The carquaise is heated by means of a fire-place of a square form called a tisar, which extends along its side. The founding or melting furnace is a square brick building laid on solid foundations being from 8 to 10 feet in each of ils fronts, and rising inside into a vault or crown about 10 feet high. At each angle of this square, a small oven or arch is constructed, likewise vaulted withm, and communicating with the melting furnace by square flues, called lu- nettes, through which it receives a powerful heat, though much inferior to that round the pots. The arches are so distributed as that two of the exterior sides of the furnace stand wholly free, while the two other sides, on which the arches encroach, offer a free spate ol only three feet. In this interjacent space, two principal openings of the furnace, of equal size m each side, are left in the building. These are called tunnels. They are destined for the introduction of the pots and the fuel. On looking through the tunnels into the inside of the furnace, we perceive to the right hand and the left, along the two/ree sides, two low platforms or sieges, at least 30 inches m height.and breadth. See Jigs, 7l5, 7l7. s , c«»» ou mtues These sieges (seals) being intended to support the pots and the cuvettes filled witk heavy materials, are terminated by a slope, which ensures the solidity of the fire-clar mound. The slopes of the two sieges extend towards the middle of the furnace so near as to leave a space of only from 6 to 10 inches between them for the hearth. The end of this is perforated with a hole sufficiently large to give passage to the liquid glass of a broken pot, while the rest is preserved by lading it from the mouth into the adjoining In the two large parallel sides of the furnace, other apertures are left much smaller ihan the tunnels, which are called ouvreaux (peep holes). The lower ones, or the ouvreauz en bas, called cuvette openings, because, being allotted to the admission of these ve<«selaL they are exactly on a level wilh the surface of the sieges, and with the floor of the halU Plates of cast-iron form the thresholds of these openings, and facilitate the ingress and egress of the cuvettes. The apertures are arched at top, with hewn stone Uke the tun- nels, and are 18 inches wide when the cuvettes are 16 inches broad. The upper and smaller apertures, or the higher ouvreaux called the lading boles, be^ cause they serve for Iransvasing the liquid glass, are three in number, and a.e placed 31 or 32 inches above the surface of the sieges. As the pots are only 30 inches high, k becomes easy to work through these openings either in the pots or the cttw««. The pots stand opposite to the two pillars which separate the openings, so that a space is left between them for one or more cuvettes according to the size of the latter. Il is obvious that if the tunnels and ouvreaux were left open, the furnace would not draw or take the requisite founding heat. Hence the openings are shut by means of fire-tUes. These are put in their places, and removed by means of two holes left in them, in correspondence with the two prongs of a large iron fork supported by an axle and two iron wheels, aiul terminated by two handles which the workmen lay hold of when they wish to move the tile. The closing of the tunnel is more complex. When it is shut or ready for the finng, « t ;■ I- i I 916 GLASS-MAKING. II the aperture appears built up with bricks and mortar from the top of the arch to the middle of the tunnel. The remainder of the door-way is closed ; 1. on the two sides down lo the bottom, by a small upright wall, likewise of bricks, and 8 inches broad, called walls of the glaye; 2. by an assemblage of pieces called pieces of the glaye^ be- cause the whole of the closure of the tunnel bears the name of glaye. The upper hole, 4 inches square, is called the tisar, through which billets of wood are tossed into the fire. Fuel is also introduced into the posterior openings. The fire is always kept up on the hearth of the tunnel, which is, on this account, 4 inches higher than the furnace- hearth, in order that the glass which may accidentally fall down on it, and which does not flow off by the bottom hole, may not impede the combustion. Should a body of glass, however, at any time obstruct the grate, it must be removed with rakes, by opening the tunnel and dismounting the fire-tile stoppers of the glaye. Formerly wood fuel alone was employed for heating the melting-furnaces of the mirror-plale manufactory of Saint Gobin ; but within these few years, the Director of the works makes use with nearly equal advantage of pit-coal. In the same establishment, two melting furnaces may be seen, one of which is fixed with wood, and the other with coals. Without any difference being perceptible in the quality of the glass furnished by either. It is not true, as has been stated, that the introduction of pit-coal has made it necessary to work with covered pots in order to avoid the discoloration of the materials, or that more alkali was required to compensate for the diminished heat in the covered pots. They are not now covered when pit-coal is used, and the same success is obtained as heretofore by leaving the materials two or three hours longer in the pots and the cu- rettes. The construction of the furnaces in which coal is burned, is the same as that with wood, with slight modifications. Instead of the close bottomed hearth of the wood furnace, there is an iron grate in the coal-hearth through which the air enters, aad the waste ashes descend. When billets of wood were used as fuel, they were well dried beforehand, by being placed a few days on a frame- work of wood called the wheel, placed two feet above the furnace and its arches, and supported on four pillars at some distance from the angles of the building. Composi'ion of plate-glass. — This is not made now, as formerly, by random trials. The progress of chemistry, the discovery of a good process for the manufacture of soda from sea salt, which furnishes a pure alkali of uniform power, and the certain methods of ascertaining its purity, have rendered this department of glass-making almost entirely new, in France. At Saint Gobin no alkali is employed at present except artificial crystals of soda, prepared at the manufactory of Chauny, subsidiary to that establish- ment. Leaden chambers are also erected there for the production of sulphuric acid from sulphur. The first crop of soda crystals is reserved for the plate-glass manufac- ture, the other crystals and the mother-water salts are sold to the makers of inferior glass. At the mirror-plate works of Ravenhead, near St. Helen's in Lancashire, soda crys- tals, from the decomposition of the sulphate of soda by chalk and coal, have been also tried, but without equal success as at Saint Gobin ; the failure being unquestionably due to the impurity of the alkali. Hence, in the English establishment the soda is obtained by treating sea-salt with pearl-ash, whence carbonate of soda and muriate of potash re- sult. The latter salt is crystallized out of the mingled solution, by evaporation at a mod- erate heat, for the carbonate of soda does not readily crystallize till the temperature of the solution falls below 60° Fahr. When the muriate of potash is thus removed, the alkaline carbonate is evaporated to dryness. Long experience at Saint Gobin has proved that one part of dry carbonate of soda is adequate to vitrify perfectly three parts of fine silicious sand, as that of the mound of Aumont near Senlis, of Alum Bay in the Isle of Wight, or of Lynn in Norfolk. It is also known that the degree of heat has a great influence upon the vitrification, and that increase of temperat \re will compensate for a certain deficiency of alkali ; for it is certain that a very strong lire always dissipates a good deal of the soda, and yet the glass is not less beautiful. The most perfect mirror-plate has constantly afforded to M. Vau- quelin in analysis, a portion of soda inferior lo what had been employed in its formation. Hence, it has become the practice to add for every 100 parts of cullet or broken plate that is mixed with the glass composition, one part of alkali, to make up for the loss that the old glass must have experienced. To the above mentioned proportions of sand and alkali independently of the cullet which may be used, dry slaked lime carefully sifted is to be added to the amount of one seventh of the sand ; or the proportion will be, sand 7 cwts. ; quicklime 1 cwt. ; dry carbonate of soda 2 cwts. and 37 lbs. ; besides cullet. The lime improves the quality of the glass; rendering it less brittle and less liable to change. The preceding quantities oC materials, suitably blended, have been uniformly found to aflbrd most advantageous results. The practice formerly was to dry that mixture as soon as it was made, in iht GLASS-MAKING. 917 arch for the materials, but it has been ascertained that this step may be dispensed with and the small portion of huniidity present is dissipated almost instantVXr they are ™rtl'e''.'„[T"'T Tf • '""V ^''^^ n''«^i«««'y applied to the inside of th? ^l but .iZ.n JT ^^ • r \l'^ ^T ^' L*?^ materials are neither fritted nor even dried, but shovel ed directly into the pot; this is called founding raw. Six workmen arc employed m shovelling-in the materials either frilled or othem^se for the X of ex^ a; S?"whX;rTh-''' '"T; r'''' T'^^-. P^^ ^^^^^ «""«' mi'xlureti^rrodTd at nrst , whenever his is melted, the second third is thrown in, and then the last These three sia^s are called the first, second, and third fusion or foundin- thr^f^ •" ^^^ ^"'''^IJ P'"a^\'<^^> the founding and refinins were both executed in the ,K)ts and It was not till the glass was refined, that it was laded into the cTmtJs where it remained only 3 hours, the time necessary for the disengagement of "he S bubbles mtrodticed by the transvasion, and for giving the metal Ihl proper co^^^^^^^^^ for casting. At present, the period requisite for founding and refining^ is equaU? divldS between the pots and the cuvettes. The materials are left 16 hours in tife pots Ind ^ many m the cuvettes; so that in 32 hours the glass is ready to be cas . Dunn, the la^ two or three hours, the fireman or tiseur ceases to add fuel ; all the openings are shut and the glass is allowed to assume the requisite fluidity; an operation SK^^Lgthe glass, or performing the ceremony. ^ ' i- cu siuppmg me The transfer of the glass into the cuvettes, is called lading, (trejetage). Before this is done the cuvettes are cleared out, that is, the dass remaininf on tLirUtomi removed and the ashes of the firing. They are lifted red hot out of the furnace Tv the wUh w^t'r^T ' '" I' ^'T''^' ""^ P'^*=^ «" ^^ •»•«" P^^te nelra tub fiM with water. The workmen, by means of iron paddles 6 feet long, flattened at one end and hammered to an edge, scoop out the fluid gkss expediliouslv"lndXowit!nto water tlilT "*' "''' '''"'"'^ '" '^' ^"^'^^''' ^'^^ * ^''^ ^i«"^^^ afterwards the Taing In this operation, ladles of wrought iron are employed, furnished with Ion* handles Ttelfti'sFr^'et chart'; T] ^'^^"^"^ ^ "^?- 'p^^^^ - ladingToles, and imm^! thfpl ^.f In f . ^^ ""^ ^^*'' '^^"^ ^^^ ^^^^^'^^^^^ Each workman dips his ladle only the te rr^.V./'"^ ' VTT '"'^ '^^ *=""""^- ^>' '^^'^ three immersions (whe^e nto a b f^n f V^'f^' S^" large iron spoon is heated so much that when plunged The founding, refining, and ceremony, being finished, they next try whether the al«« is^S 'rr^L ^^ ''ll "■^"' '^^ ^".^ ^^ ^ ^^ '^ clipped int^o'the'tuc'etw'h IS called drawing the glass; the portion taken up being allowed to runoff" nlturallv assumes a pear-shape, from the appearanceof which, they can judge if thrcon^iste^^^^^^^^ mZ' '"^ ;^ ""^ "'!; ^"^^'"^ ^^'"^•"- '^ «" ^' ""''t, the c«i^/.f are taken ouT'^ fu nace, and conveyed to the part of the halle where their contents are to be poured ouu This process requires peculiar instruments and manipulations. Ca*/t«?.— While the glass is refining, that is, coming to its highest noint of nerfeetinn preparation ,s made for the most important process,'the casUng ofX pkte whose success crowns all the preliminary labors and cares. ^The oven or mrZ Jdeslii^d to receive and anneal the plate is now heated by its small fire or /tW, t?sucTa pS Its sole may have the same temperature as that of the plates, being nearly red hot at the moment of their being introduced. An unequal degree of heat in thlmrauaise would rf'r K?*""'' '^'';" ^'*''' 7.^" '"^^^"^ ^^^'^ i^ ^hen rolled towards theTontdrrir tile oven.' "''"' "^ ^"""'"' '"^ ''' ''''^'''' '' ^^""^^'^^ ^^'^'^^^^ ^« ^he level ofThe sole of The table T, fig. 724, is a mass of bronre, or now preferably cast iron about 10 feet long, o feet broad, and from 6 to 7 inches thick, supported by a frameof carne^trv which res .on ,hree cast iron wheels. At the end of 'the table oppLheTthat neTt to t'hefr^^^ of fh« oveq, IS a very strona; frame of timber-work called rh*» nnLit I ? ^ ^5 *^"' which the bronze roller which spreads the Rlasll ,;id:'i;fo eL'd a^lthVc'^^^^^ T^" IS 5 feet long by 1 foot ,n diameter; it is thick in the metal but Lllow in the axfs The same ro Her can serve onlv for two nlat^e «» r»n« «„.♦• u ""^ow m ine axis, ine an'l the firsf .« l«i,l VciT. ! / m^^^J^t One casting, when another is put in its place, an' the first is laid aside to coo ; for otherwise the hot roller would at a third castine make the plate expand unequa y, and cause it to rrai.lr iVh^ ti 1? casting aeiion iHpv nr*. in.ii oc.M- .« c «-«*««!>e ii lo cracK. When the rollers are not m the two sfdes or- i^ ^TmI n X v ''''?^'" I""^"'^^'' ^'^^ '^^'^ ^"^P'^'y^d by sawvers. On de.t Z to .nl,r^ the rnlW f' "'^f ''' ^^""'*'' ^'^ ^^^ P"^"«' ^ars of bronze, /, /, ts rle'mLT^^^^^^^ tX^fein^rhufa;^ ^"',' ^'^ '''^T'. ^^ ''^'^ ii !!l • (' -ii .V- 918 GLASS-MAKING. The tongs t, fig. 724, are made of four iron bars, bent mio a square frame in their middle, for embracing the bucket. Four chains proceeding from the corners of the frame V are united at their other ends into a ring 'which fits into the hook of the craoe. 724 Things bting thus arranged, all the workmen of the foundry co-operate in the manipn- lations of the casting. Two of them fetch, and place quickly in front of one of the lower openings, the small cuvette-carriage, which bears a forked bar of iron, having two pron?s corresponding to the two holes left in the fire-tile door. This fork, mounted on the axle of two cast-iron wheels, extends at its other end into two branches terminated by handles, by which the workmen move the fork, lift out the tile stopper, and set it down against the outer wall of the furnace. The instant these men retire, two others push forward into the opening the extre- mity of the tongs-carriage, so as to seize the bucket by the girdle, or rather to clamp it. At the same time, a third workman is busy with an iron pinch or long chisel, detaching the bucket from its seat, to which it often adheres by some spilt -lass ; whenever it is free, he withdraws it from the furnace. Two powerful branches of iron united by a bolt, like two scissor blades, which open, come together, and join by a quadrant near the other end, form the tongs-carriage, which is monnied upon two wheels like a truck. The same description will apply almost wholly to the iron-plate carriage, on which the bucket is laid the moment it is taken out of the furnace ; the only difl!erence in its construction is, that on the bent iron bars which form the tail or lower steps of this car- nage (m place of the tones) is permanently fastened an iron plate, on which the bucket IS placed and carried for the casting. Whenever the cuvelU is set upon its carriage, it must be rapidly wheeled to its station near the crane. The tongs t above described are now applied to the girdle, and are then hooked upon the crane by the suspension chains. In this position the bucket is skim- med by means of a copper tool called a sabre, because it has nearly the shape of that weapon. Every portion of the matter removed by the sabre is thrown into a copper ladle (j>oc}ie de gamin), which is emptied from time to time into a cistern of water. After being skimmed, the bucket is lifted up, and brushed very clean on its sides and bottom ; then by the double handles of the suspension-tongs it is swung round to the table, where It is seized by the workmen appointed to turn it over; the roller having been previously laid on Its ruler-bars, near the end of the table which is in contact with the annealing oven. The cuvette-men begin to pour out towards the right extremity e of the roller, and terminate when it has arrived at the left extremity d. While preparing to do so, and at the instant of casting, two men place within the ruler-bar on each side, that is, between the bar and the liquid glass, two iron instruments called handsy rriy rn, m, m, which pre- vent the glass from spreading beyond the rulers, while another draws along the table the wiping bar c, <•, wrapped in linen, to remove dust, or any small objects which may inter- pose between the table and the liquid glass. Whenever the melted glass is poured out, two men spread it over the table, guiding the roller slowly and steadily along, beyond the limits of the «lass,and then run it smartly mto the wooden standard prepared for its reception, in placeof the trestles v, v. The empty bucket, while still red-hot, is hung a?ain upon the crane, set on its plate- iron carriage, freed from its tongs, and replaced in the furnace, to be speedily cleared out anew, and charged with fresh fluid from the pots. If while the roller glides along, the two workmen who stand by with picking tools, perceive tears in the matter in ad- vance of the roller, and can dexterously snatch them out, they are suitably rewarded, according to the spot where the blemish lay, whether in the centre, where it would have proved most detrimental, or near the edge. These tears proceed usually from GLASS-MAKING. 919 nnall portions of semi-vitrified matter which fall from the vault of the furnace, and from their density occupy the bottom of the cuvettes. While the plate is still red-hot and ductile, about 2 inches of its end opposite to the earquaise door is turned up with a tool; this portion is called the head of the mirror ; against the outside of this head, the shovel, in the shape of a rake without teeth, is ap- plied, with which the plate is eventually pushed into the oven, while two other workmen press upon the upper part of the head with a wooden pole, eight feet long, to preserve the plate in its horizontal position, and prevent its being warped. The plate is now left for a few moments near the throat of ♦he earquaise^ to give it solidity ; after which it is pushed farther in by means of a very long iron tool, whose extremity is forked like the letter y, and hence bears that name ; and is thereby arranged in the most suitable spot for allowing other plates to be introduced. However numerous the manipulations executed from the moment of withdrawing the cuvette from the furnace, till the cast-plate is pushed into the annealing oven, I have seen them all performed in less than five minutes; such silence, order, regularity, and despatch prevail in the establishment of Saint-Gobin. When all the plates of the same casting have been placed in the earquaise, it is sealed up, that is to say, all its orifices are closed with sheets of iron, surrounded and made tight with plastic loam. With this precaution, the cooling goes on slowly and equably in every part, for no cooling current can have access to the interior of the oven. After they are perfectly cooled, the plates are carefully withdrawn one after another, keeping them all the while in a horizontal position, till they are entirely out of the car' quaise. As soon as each plate is taken out, one set of workmen lower quickly and steadily the edge which they hold, while another set raise the opposite edge, till the glass be placed upright on two cushions stuflled with straw, and covered with canvass. In this vertical position they pass through, beneath the lower edge of the plate, three girths or straps each four feet long, thickened with leather in their middle, and ending in wooden handles ; so that one embraces the middle of the plate, and the other two, the ends. The workmen, six in number, now seize the handles of the straps, lift up the glass closely to their bodies, and convey it with a regular step to the warehouse. Here the head of the plate is first cut oflf with a diamond square, and then the whole is atten- tively examined, in reference to its defects and imperfections, to determine the sections which must be made of it, and the eventual size of the pieces. The pairings and small cuttings detachet are set aside, in order to be ground and mixed with the raw materials of another glass-pot. The apartment in which the roughing-down and smoothing of the plates is performed, is furnished with a considerable number of stone tables truly hewn and placed apart like billiard tables, m a horizontal position, about 2 feet above the ground. They are rec- tangular, and of diflerent sizes proportional to the dimensions of the plates, which they ought always to e^iceed a little. These tables are supported either on stone piUars or wfoden frames, and are surrounded with a wooden board whose upper edge stands some- what below their level, and leaves in the space between it and the stone all round an in- terval of 3 or 4 inches, of which we shall presently see the use. A cast plate, unless formed on a table quite new, has always one of its faces, the one next the table, rougher than the other; and with this face the roughing-down begins. With this view, the smoother face is cemented on the stone table with Paris-plaster. But often, instead of one plate, several are cemented alongside of each other, those of the same thickness being carefully selected. They then take one or more crude plates of about one third or one fourth the surface of the plate fixed to the table, and fix it on them with liquid gypsum to the large base of a quadrangular truncated pyramid of stone, of a weight proporiioned to its extent, or about a pound to the square inch. This pyramidal muUer, if small sized, bears at each of its angles of the upper face a peg or ball, which the grinders lay hold of in working it; but when of greater dimension, there is adapted to it horizontally a wheel of slight construction, 8 or 10 feet in diameter, whose circumference is made of wood rounded so as to be seized with the hand. The upper plate is now rubbed over the lower ones, with moistened sand applied between. This operation is however performed by machinery. The under plate being fixed or imbedded in stucco, on a solid table, the upper one likewise imbedded by the same cement m a cast iron frame, has a motion of circumrotalion given to it closely resem- bling that communicated by the human hand and arm, moist sand being supplied between them. While an eccentric mechanism imparts this double rotatory movement to the upper plate round its own centre, and of that centre rojind a point in the lower plate, this plate, placed on a moveable platform, changes its position by a slow horizonta. motion, both m the direction of its length and its breadth. By this ingenious con- trivance, which pervades the whole of the grinding and polishing machinery, a remark- able regularity of friction and truth of surface is produced. When the plates are suffi- eiently worked on one face, they are reversed in the frames, and worked together on 'i II II u 1 B 920 GLASS-MAKIT^G. the ether. The Paris plaster is usually colored red, in order to show any defects in tht ^la$<:. The smoothing of the plates is effected on the same principles by the use of moist emery washed to successive degrees of fineness, for the successive stages of the operation ; and the polishing process is performed by rubbers of hat-felt and a thin paste of colcothar and water. The colcothar, called also crocus, is red oxyde of iron prepared by the igni- tion of copperas, with grinding and elutriation of the residuum. The last part or the poli>*hing process is performed by hand. This is managed by fe- males, who slide one plate over another, while a little moistened putty of tin finely levi- gated is thrown between. Large mirror-plates are now the indispensable ornaments of every large and sumptuous apartment ; they diffuse lustre and gayety round them, by reflecting the rays of light in a thousand lines, and by multiplying indefinitely tne images of objects placed between op- posile parallel planes. The silvering of plane mirrors consists in applying a layer of tin-foil alloyed with mer- cury to their posterior surface. The workshop for executing this operation is provided with a great many smooth tables of fine freestone or marble, truly levelled, bavin? round Iheir contour arising ledge, within which there is a gutter or groove which terminates by a slight slope in a spout at one of the corners. These tables rest upon an axis of wood or iron which runs along the middle of their length ; so that they may be inclined easily into an angle with the horizon of 12 or 13 degrees, by means of a hand-screw fixed be- low. They are also furnished with brushes, with glass rules, with rolls of woollen stuff, several pieces of flannel, and a great many weights of stone or cast-iron. The glass-tinner, standing towards one angle of his table, sweeps and wipes its surface with the greatest care, along the whole surface to be occui»ied by the mirror-plate; then taking a sheet of tin-foil adapted to his purpose, he spreads it on the table, and applies it closely with a brush, which removes any folds or wrinkles. The table being hori- zontal, he pours over the tin a small quantity of quicksilver, and spreads it with a roll of woollen stuff; so that the tin-foil is penetrated and apparently dissolved by the mer- cury. Placing now two rules, to the right and to the left, on the borders of the sheet, he pours on the middle a quantity of mercury sufficient to form everywhere a layer about the ihickness of a crown piece; then removing with a linen rag the oxyde or other im- purities, he applies to it the edge of a sheet of paper, and advances it about half an inch. Meanwhile another workman is occupied in drying very nicely the surface of the glass that is to be silvered, and then hands it to the master workman, who, laying it flat, places its anterior edge first on the table, and then on the slip of paper; now pushing the glass forwards, he takes care to slide it along so that neither air nor any coal of oxyde on the mercury can remain beneath the plate. When this has reached its position, he fixes it there by a weieht applied on its side, and gives the table a gentle slope, to run off* all the loose quicksilver by the gutter and spout. At the end of five minutes he covers the mirror with a piece of flannel, and loads it with a great many weights which are left upon it for twenty-four hours, under a gradually increased inclination of the table. By this time the plate is ready to be taken off the marble table, and laid on a wooden one •loped like a reading desk, with its under edge resting on the ground, while the upper is raised successively to difl'erent elevations by means of a cord passing over a pulley in the ceiling of the room. Thus the mirror has its slope graduated from day to day, till it finally arrives at a vertical position. About a month is required for draining out the superfluous mercury from large mirrors; and from 18 to 20 days from those of moderate size. The sheets of tin-foil being always somewhat larger than the glass plate, their edges must be paired smooth oflT, before the plate is lifted ofl" the marble table. Process for silvering concave mirrors. — Having prepared some very fine Paris plaster by passing it through a silk sieve, and some a little coarser passed through hair-cloth, the first is to be made into a creamy liquor with water, and after smearing the concave surface of the glass with a film of olive oil, the fine plaster is to be poured into it, and spread by turning about, till a layer of plaster be formed about a tenth of an inch thick. The second or coarse plaster, being now made into a thin paste, poured over the first, and moved about, readily incorporates with it, in its imperfectly hardened state. Thus an exact mould is obtained of the concave surface of the glass, which lies about three quar- ters of an inch thick upon it, but is not allowed to rise above its outer edge. The mould, being perfectly dried, must be marked with a point of coincidence on the glass, in order to permit of its being exactly replaced in the same position, after it has been lifted out. The mould is now removed, and a round sheet of tin-foil is applied to it, so large that an inch of its edge may project beyond the plaster all round ; this border being necessary for fixing the tin to the contour of the mould by pellets of white wax soAened a little with some Venice turpentine. Before fixing the tin-foil, however, it must be properly spread over the mould, so as to remove every wrinkle; which the GLASS-MAKING. 92i pliancy of the foil easily admits of, by uniform and well-directed pressure with the fingers. The glass being placed in the hollow bed of a tight sack filled with fine sand, set in a well-jointed box, capable of retaining quicksilver, its concave surface must be dusted with sifled wood-ashes, or Spanish white contained in a small cotton bag, and then well wiped with clean linen rags, to free it from all adhering impurity, and particularly the moisture of the breath. The concavity must be now filled with quicksilver to the very lip, and the mould, being dipped a little way into it, is withdrawn, and the adhering mercury is spread over the tin with a soft flannel roll, so as to amalgamate and brighten its whole surface, taking every precaution against breathing on it. Whenever this brightening seems complete, the mould is to be immersed, not vertically, but one edge at first, and thus obliquely downwards till the centres coincide ; the mercury meanwhile being slowly displaced, and the mark on the mould being brought finally into coinci- dence with the mark on the glass. The mould is now left to operate by its own weight, in expelling the superfluous mercury, which runs out upon the sand-bag and thence into a groove in the bottom of the box, whence it overflows by a spout into a leather bag of reception. After half an hour's repose, the whole is cautiously inverted, to drain -iff the quicksilver more completely. For this purpose, a box like the first is provided with a central support rising an inch above its edges; the upper surface of the support being nearly equal in diameter to that of the mould. Two workmen are required to execute the following operation. Each steadies the mould with the one hand, and raises the box with the other, taking care not to let the mould be deranged, which they rest on the (convex) support of the second box. Before inverting the first apparatus, how- ever, the reception bag must be removed, for fear of spilling its mercury. The redun- dant quicksilver now drains off; and if the weight of the sandbag is not thought sufli- cient, supplementary weights are added at pleasure. The whole is left in this position for two or three days. Before separating the mirror from its mould, tl^ border of tin- foil, fixed to it with wax, must be pared off" with a knife. Then the weight and sandbag being removed, the glass is lifted up with its interior coating of tin- amalgam. For silvering a convex surface. — A concave plaster mould is made on the convex glassy and their points of coincidence are defined by marks. This mould is to be lined with tinfoil, with the precautions above described ; and the tin surface being first brightened with a little mercury, the mould is then filled with the liquid metal. The glass is to be well cleaned, and immersed in the quicksilver bath, which will expel the greater part of the metal. A sandbag is now to be laid on the glass, and the whole is to be inverted as in the former case on a support ; when weights are to be applied to the mould, and the mercury is left to drain off for several days. If the glass be of large dimensions, 30 or 40 inches, for example, another method is adopted. A circular frame or hollow ring of wood or iron is prepared, of twice the diam- eter of the mirror, supported on three feet. A circular piece of new linen cloth of close texture is cut out, of equal diameter to the ring, which is hemmed stoutly at the border, and furnished round the edge with a row of small holes, for lacing the cloth to the ring, so as to leave no folds in it, but without bracing it so tightly as to deprive it of the elas- ticity necessary for making it into a mould. This apparatus being set horizontally, a leaf of tinfoil is spread over it, of sufficient size to cover the surface of the glass; the tin is first brightened with mercury, and then as much of the liquid metal is poured on as a plane mirror requires. The convex glass, well cleaned, is now set down on the cloth, and its own weight, joined to some additional weights, gradually presses down the cloth, and causes it to assume the form of the glass which thus comes into close contact with the tin submersed under the quicksilver. The redundant quicksilver is afterwards drained off by inversion, as in common cases. The following recipe has been given for silvering the inside of glass globes. Melt in an iron ladle or a crucible, equal parts of tin and lead, adding to the fused alloy one part of bruised bismuth. Stir the mixture well, and pour into it as it cools, two parts of dry mercury ; agitating anew and skimming off the drossy film from the surface of the amal- gam. The inside of the glass globe, being freed from all adhering dust and humidity, is to be gently heated, while a little of the semi-fluid amalgam is introduced. The liquidity being increased by the slight degree of heat, the metallic coating is applied to all the points of the glass, by turning round the globe in every direction, but so slowly as to favor the adhesion of the alloy. This silvering is not so substantial as that of plane mir- rors : but the form of the vessel, whether a globe, an ovoid, or a cylinder, conceals or palliates the defects by counter reflection from the opposite surfaces. Colored Glasses and Artificial Gems, — The general vitreous body preferred by Fon- tanieu in his treatise on this subject, which he calls the Mayence base, is prepared in the following manner. Eight ounces of pure rock-crystal or flint in powder, mixed with 24 ounces of salt of tartar, are baked and left to cool. This is afterwards poured i 922 GLASS-MAZING. II whpn .h r f^ ,''',!'**"\*"? Hf*l^^ "^'^^ ^""^^ "'^"^ »<^'^ t'" it ceases to effervewe, when the fnt IS o be washed till the water comes off tasteless. The frit is now dried Jr^^.l'?/ w tJ" n . Truf ^"^ "^^^ ^^"^» '^"^ ^^^ °^^^'"'^ i« »« be levigated and elu- triaied with a l.ttie distilled water. An ounce of calcined borax is to be added to abour J2 ounces of the preceding mixture in a dry state, the whole rubbed together in a porce Iain mortar, then melted in a clean crucible, and poured out into cold water. ThisVitre- ous matter must be dried, and melted a second and a third time, always in a new crucible, th,i I'JT ""^^V"^ P«"[^«l »"lo cold water as at first, taking care to separate the lead lddP.r/nJ',h ""f • ^u • ^' ^^'i ^JT ^^""'^ t° P°^^«^' fi^« ^--^chms of nitre are to be added, and the mixture being melted for the last time, a mass of crystal will be found in the crucible with a beautiful lustre. The diamond is well imitated by this Mayence J^hi nunT^'.r IV. rj^/'" "^''"^ "y ^" obtained, according to M. Fontanieu, from eigh ounces of white lead, two ounces of powdered borax, half a grain of manginese. and three ounces of rock-crystal, treated as above. luan^anese, »Z«1T k"^ !f^"^'^*''^^ ^T' *'^ obtai'icd from metaUic oxydes. The oriental topaz is prepared by adding oxyde of antimony to the base; the amethyst from man^aneseT with • little purple precipitate of Cassius; the beryl from antimony and a very liitle^obl LiaT ""w P ^ ^'""^"".^ S"'^ "P^' ^T ^«^»-«"-^r (cWoride of silver) ; blue stone from cobalt. See Pastes and Pigments ViTKiFiABLE. *c nvm The following are recipes for making the different kinds of glass. fc«I;.f "*!'/* ^'7*— ^^ P«»"ds of dry glauber salts; 12 pounds of soaper salts; a half bushel of waste soap ashes ; 56 pounds of sand ; 22 pounds of slass skimmi^s 1 gill's. ^''''' '" ^^^'' ^^ P°""^' °^ ^^^'- This mixture affords a S ir^en teiVo^nlHT"?'^!;'^^ sand, 100 parts; kelp, 30 to 40; lixiviated wood ashes, from 160 Spoken K' im 7u ^u k' ^^ '? i^ P"'^' P°"^^'^ '^^y^ «0 ^« 100 P^'-ts c""et or T„ ?in K't I , ^^ K^'*^^ ^^ "'^^' ^^^ proportion of kelp may be diminished. crLienT Jd hHTl "'"' '" '^^ neighborhood of Valenciennes, an unknown in- gredient, so Id by a Belgian, was employed, which he called spar. This was discovered Vy chemical analysis to be sulphate of baryta. The glass-makers observed that [^ bottles which contained some of this substance were denser, more homogeneous more fusible, and worked more kindly, than those formed of the common materLr When «o?i ~. K ^ 7"^^ ^^*^' ^"^ exposed m a proper furnace, vitrification read.ly ensues, and the glass may be worked a little under a cherry red hea with S much ease a»a glass of lead and has nearly the same lustre. Since the ord^nXu^ of glass-makers are not familiar with atomic proportions, they should have recourse to a scientific chemist, to guide them in using such a proportion of sulphatlofTryta as Jm?Zt'^'t7n^tl^n^T^' ^^r;-^^ P^'^"'^' °^ ^"^ ?^^"^^'- «^^^'- 10 poinds of soaper salts, half a bushel of lixiviated soap waste; 50 pounds of sand- 2'> oound^ nC glass pot skimmings ; 1 cwt. of broken green glass ^ "* "» sanu , z^ pounds of lJ^' tnZT fu"r^^. ^""'^f ^""^ ^^"^^5 200 of good soda ash; 33 of lime; from 6 mt '/ !? "^; """^ f^^'' ' 'J "/ °^an?anese ; 100 of broken glass ^ ' Je;'^5*:rf wwtetu^^'''°""'^^'p°^^^^^^ '^^^^^^^^^ ^^^'--^^^ io^--^ Rihillf' '".^i"^ ^''7^^'^ ^**'^^' 5 100 of sand ; 20 of chalk ; and 2 of saltpetre .iottuil^l^ntnl''"''"'''^' ''" of «""<'-'-' i 10 of saltpetre, J of a«. Jle^ef^^^Vof'::'L^):' '''"''' ■""'"""' '""^ ''"^o ■^""'^ "■»«' iof-"- pei^etToWafgair"' ""'= '" "' '"' "'«^' 40 of purified pearl«h, 20of s.1.. mL^^^i^'^. "'' '•''* *"'•!} ""^^ ' ^° "'■ ''^ '««>! 8 of pearlash purified; 2 of «iu peire j a litUe aisenious acid and manganese. '^ , * w muh* GLASS-CUTTING. 923 A seventh. -100 of sand ; 45 of red lead; 35 of purified pearlashes ; 1 of manganese ; i of arsenious acid. 8. Plate glass. — Very white sand 300 parts ; dry purified soda 100 parts ; carbonate of lime 43 parts; manganese 1 ; cullet 300. Another.— Finest sand 720; purified soda 450; quicklime 80 parts; saltpelrre 25 parts ; cullet 425. A little borax has also been prescribed ; much of it communicates an exfoliating pro- perty to glass. Tabular view of the composition of several kinds of Glass. Silica . No.l. 71-7 No. 2. 69-2 No. 3. No. 4. No. 5. No. 6. No. 7. No. 8. No. 9. 1 62-8 69-2 60-4 53-55 59-2 51-93 42-5 Potash 12-7 15-8 22-1 8-0 3-2 5-48 9-0 \3-77 11-7 Soda - 2-5 3 3-0 S. pot. Lime - 10-3 7-6 12-5 13-0 20-7 29-22 0-6 Alumina 0-4 1-2 3-6 10-4 6-01 1-8 Magnesia 20 ) 0-6 0-6 Oxyde of iron 0-3 0-5 V2.6 1-6 3-8 5-74 0-4 — manganese 0-2 J 1-0 1 — lead - 28-2 33-28 43-5 1 Baryta 0-9 No. 1 is a very beautiful white wine glass of Neuwelt in Bohemia. No. 2. Glass lubes, much more fusible than common wine glasses. No. 3. Crown glass of Bohemia. No. 4. Green glass, for medicinal vials and retorts. No. 5. Flask glass of St. Etienne, for which some heavy spar is used. No. 6. Glass of Sevres. No. 7. London glass employed for chemical and physical purposes. No. 8. English flint glass. No. 9. Guinand's flint glass. The manufacture of Glass beads at Murano near Venice, is most ingeniously simple. Tubes of glass of every color are drawn out to great lengths in a gallery adjoining the glass-house pots, in the same way as the more moderate lengths of thermomfeter and barometer tubes are drawn in our glass-houses. These tubes are chopped into very smaL pieces of nearly uniform length on the upright edge of a fixed chisel. These elementary cylinders, being then put in a heap into a mixture of fine sand and wood ashes, are stirred about with an iron spatula till their cavities get filled. This curious mixture is now transferred to an iron pan suspended over a moderate fire and continually stirred about as before, whereby the cylindrical bits assume a smooth rounded form ; so that when re- moved from the fire and cleared out in the bore, they constitute beads, which are packed in casks, and exported in prodigious quantities to almost every country, especially to Africa and Spain. GLASS CUTllNG AND GRINDING, for common and optical purposes. By this *nechanical process the surface of glass may be modified into almost any ornamental or useful form. 1. The grinding of crystal ware. This kind of glass is best adapted to receive polished facets, both on account of its relative softness, and its higher refractive power, which gives lustre to its surface. The cutting shop should be a spacious long apart- ment, furnished with numerous sky-lights, having the grinding and polishing lathes aiTanged right under them, which are set in motion by a steam engine or water-wheel at (^25 _ one end of the building. A shaft is fixed as usual in gallowses along the ceiling ; and from the pulleys of the shaft, bands descend to turn the different lathes, by passing round the driving pulleys near their ends. The turning lathe is of the simplest construction. Fig. 725, D is an iron spindle with two well-turned prolongations, running in the iron puppets a a, between two concave bushes of tin or type metal, which may be pressed more or less together by the thumb-screws shown in the figure. These two puppets are made fast to the wooden support b, which is attached by a strong screw and bolt to the longitudinal beam of the workshop a. e is the fast and loose pulley for putting the 924 GLASS-CUTTING. GLASS-CUTTING. 925 1 i lathe into and out of gear with the drivm? shaft. The projecting end of Itc spindle n furnished with a hollow head-piece, into which the rod c is pushed ti-ht. This rod car- ries the cutting or grinding disc plate. For heavy work, this rod is fixed into the head by a screw. When a conical fit is preferred, the cone is covered with lead to increase the friction. Upon projecting rods or spindles of that kind the different discs for cutting the elass are made fast. Some of these are made of fine sandstone or polishing slate, from 8 to 10 inches m diameter, and from| to ^ inch thick. They must be carefully turned and polish- ed at the lathe, not only upon their rounded but upon their flat face, in order to grind and polish m their turn the flat and curved surfaces of glass vessels. Other discs of the ^me diameter but only | of an inch thick, are made of cast tin truly turned, and erve for pohshin- the vessels previously ground; a third set consist of sheet iron from i. to | an inch thick, and 12 inches in diameter, and are destined to cut grooves in glass by the aid of sand and water Small discs of xvelUhammered copper from | to 3 inches in diameter, whose circumference is sometimes flat, and sometimes concave or convex, serve to make all sorts of delmealions upon glass by means of emery and oil. Lastly, there are rods of copper or brass furnished with small hemispheres from i to J of an inch in diameter, to excavate round hollows in glass. Wooden discs are also employed for polish- m^ made of white wood cut across the grain, as also of cork. The culling of deep indentations, and of grooves, is usually performed by the iron disc, with sand and water, which are allowed constantly to trickle down from a woe, .«^ io • u ■ ^- ^ "^^"^ ®,C!*"^ ^"'^ ^^ater. That disc is one sixth of an inch thfck «r iJc • "^ ^' "" ^'*™^^^''- ^^'^^ ^"''^^^'' ^"«" ^^^^ ^^""^ ^«lf «" inch thick, and more or less in diameter according to the curvature of the surface, the grooves may be widen- t«t.r on f^.K*""^ ?• f SP^rV' T^^ ^^ "^^^ smoothed down with the sandstone disc and water, and then polished with the wooden disc about half an inch thick, to whose edge ^e workman applies, from lime to time, a bag of fine linen containing some ground pumice moistened with water When the cork or wooden di.c edged with hat felt is used fw polishing, putty or colcothar is applied to it. The above several processes in a lar-e manufactory are usually committed to several workmen on the principle of the division o^[' ^° ^^^ ^^^^ ""^y become expert in his department. .«r I. ^""'"'^^''f "*/ ^^'^'^^^ glasses.-The glasses intended for optical purposes, being llclTnllr^T'^' "'" called lenses; and are used either as simple magnifiers and Tpec! InJ I'rh ^^^^'^^^^^ «"^ microscopes. The curvature is always a portion of a sphere, and either convex or concave. This form ensures the convergence or divergence of the Zllf ^'^^'' '^'' P"'' '^'^""^^ '^^°*' *^ '^' P«"«^i"? does the brightness of the To ^^"5 ?"?K '"^ ""^ ^^^ '^"'^' *' performed in brass moulds, either concave or convex, hinfnrv. T' """^^^^r" "' ^^^^ ^^'"^ ^" ^^*^ ^^^^^^ ? «"d may be worked either b^ ?.^ir ^ Tfu T'^\u "^-^^"r^ '^ ^''' ^"^ °"^ °»l 0^ *>''=^^s «r copper plate to suit ihj cu vature of the lens, the circular arc being traced by a pair of compasses. In this way both a convex and concave circular gauge are obtained. To these gauges the brass moulds are turned. Sometimes, also, lead moulds are used. After the two moulds are made, they are ground face to face with fine emery ,1 Iv^jIZlo''^ ^iT"' il now roughed into a circukr form by a pair of pincers, leaving In! H "• ' ^^", /^^ ^""f hed lens ought to be, and then smoothed round upon the «onedisc or in an old mould with emery and water, and is next made fast toV hold- «Ll;Ur ■ If- *^""f'«'^,/'^ ^J^°"°d ^'^^l plate having a screw in its back ; and is somewhat smaller in diameter than the lens, and two thirds as thick. This as turned concave upon li the lathe, and then attached to the piece of glass by drops of pitch applied to several points of its surface, taking care, while the pilch is warm, that the centre of the glass coincides with the centre of the brass plate. This serves not merely as a holdfast, by enabling a person to seize its edge with the fingers, but it prevents the glass from bend- ing by the necessary pressure in grinding. . The glass must now be ground with coarse emery upon its appropriate mould, whethe" convex or concave, the entery being all the time kept moist with water. To prevent the heat of the hand from affecting the glass, a rod for holding the brass platens screwed to its%ack. For every six turns of circular motion, it must receive two or three rubs across the diameier in diflerent directions, and so on alternately. The middle point of the glass must never pass beyond the edge of the mould; nor should strong pressure be at any lime a^iplied. Whenever the glass has assumed the shape of the mould, and touches it in every point, the coarse emery must be washed away, finer be substituted in its place, and the grinding he continued as before, till all the scratches disappear, and a uniform dead surface be produced. A commencement of polishing is now to be given with pum- ice stone powder. During all this time the convex mould should be occasionally worked in the concave, in order that both may preserve their correspondence of shape between them. After the one surface has been thus finished, the glass must be turned over, and treated in the same way upon the other side. Both surfaces are now to be polished. With this view equal parts of pitch and rosin must be melted tosether, and strained through a cloth to separate all impurities. The concave mould is next to be heated, and covered with that mixture in a fluid state to the thickness uniformly of one quarter of an inch. The cold convex mould is now to be pressed down into the yielding pilch, its surface being quite clean and dry, in order to give the pilch the exact form of the ground lens ; and both are to be plunged into cold water till they be chilled. This pilch impression is now the mould upon which the glass is to be polished, according to the methods above described, with finely washed colcothar and water, till the surface become perfectly clear and brilliant. To prevent the pilch from changing its figure by the friction, cross lines must be cut in it about |an inch asunder, and l-12lh of an inch broad and deep. These grooves remove all the super- fluous parts of the polishing powder, and tend to preserve the polishing surface of the pitch clean and unaltered. No additional colcothar after the first is required in this part of the process; but only a drop of water from time to time. The pitch gets warm as the polishing advances, and renders the friction more laborious from the adhesion between the surfaces. No interruption must now be suflfered in the work, nor must either water or colcothar be added ; but should the pitch become too adhesive, it must be merely breathed upon, till the polish be complete. The nearer the lens is brought to a true and fine surface in the first grinding, the better and more easy does the polishing become. It should never be submitted to this process with any scratches perceptible in it, even when examined by a magnifier. As to small lenses and spectacle eyes, several are ground and polished together in a mould about 6 inches in diameter, made fast to a stiflening plate of brass or iron of a shape corresponding with the mould. The pieces of glass are affixed by means of drops of pitch, as above described, to the mould, close to each other, and are then all treated as if they formed but one large lens. Plane glasses are ground upon a surface of pilch rendered plane by the pressure of a piece of plate glass upon it in its softened state. Lenses are also ground and polished by means of machinery, into the details of which the limits of this work will not allow me to enter. Glass in the Exhibition. — So far as may be inferred, from the analysis of ordinary commercial samples of window-glass, this substance has not only a verv Variable compo- sition, but, worse than this, is out of all keeping with anything like (lefiiiite proportioa That it should be full of strise, and, therefore, refract the rays of light equally, as it does, so as to produce the most hideous appearances of distortion, is a mere natural consequence of its mechanical composition, which might, and must one day, be corrected ; but that whole nations should have come to view this defect as an unavoidable peculiarity, is precisely one of those surprising facts which demonstrate the influence of habit over the powers of the mind, and show how easily human reason can reconcile itself to the most gross incon- sistencies. If window-glass had one uniform atomic composition, the tendency to form these striae would nowhere exist in excess; and, therefore, their production would diminish as the skill of the workmen increased ; but, with the present variable com- pound, the glass stretches unequally in ditferent parts, by an equal application of force, and, in spite of human skill, presents a result alternately thick or thin, as accident determines. That these striae have not the same composition as the parts surrounding them is very obvious, from the circumstance that, if striated glass be cut to an uniform thickness, and polished on both sides, the optical defects remain but little changed, and occasionally they are fouml to be increased. Again it is known, that the more complex the composition of any glass may be, the greater the liability to this striated 526 GLASS. GLASS. 927 8tructure,-of which flint ?la«s offers an opposite illustration • for here in addition in ^r:vi[v'nr--rTP'r,"^'^ ^^^'^ '^' '^''^'^^^ ^'^^ i« superadded No\" the sZifi^ ilZ^ "f ^'I'^'-^te of lead is verj; high compared with that of silicate of soda Sh wit in.; n^' r.^™P^^^^^ ^° *^" exact quantity to form a chemical SmbKon Inlu- .1? K^'^r*^'^ ^^'"^ mechanical mixtur'e is produced of very difft rent densities throughout ; and the product, under the action of light, displays^poLanentlv mhed to^Mhp? ir ''^" ^^^" «y^"P «"^ ^^*^'?«'- ^l««»'ol aSd water afe rifr! r ^ r n • .*^^^ J' -^ '^y' ^ ^^"^« «f cu'-^-ed lines are formed by the uneoual lefract.on of the two fluids, which entirely disappear, so soon as perfect admTxtTe^h^ ^ffecL^'th'p nt"^''^ '■'"""^" '^'' "^^^ «^ «•" 'g^^^«' ^'^^ the^utter imp'S nS bi^ necessary union between its various parts. Although, however th sJan- easoLH "^^^*^^"if 7' y^\^ a chemical way, nature performs such operations whh ease and unerring fidelity. The French chemist, Berthier long ago proved that nTanv neutral salts combine together by fusion in atomic proportfons^anrform tw and atom fo^nT''""'^'; ^f ' ''^^"^*' «f P^'*'-^^^^ ^"d carbonate of soda wT.en mixed Si f fu ; ""'*^ .^"? P'^""^ ^ compound more easy of fusion than The mS fusible of the two :-sim.larly, either of these carbonates w-ill act with carbonatHf ^nA,{-Kl "*' f r''"''*' \"^ ^?^'"' ^«"^-«P«^ ^"d «»lph^te of lime, two r oSablv infusible substances, when mixed, melt readily, at a low red heat inM « fl.,: i i •/ and transparent as water. It i^ useless to -Multiply ^xallefoA^ sands exist; and the alkaline and earthy silicates fomn7e?ception to thi^.l^^^^^^^ universal rule. A mixture of silicate of potash and s^cate of soTTni v' '* ratios, fuse much more readily than eitherof tLTatne But n^^^^ "^"'"" attempt to fuse these two bodies together, in anrier p" ttionThIn tharKl'/h they are naturally disposed to combine —.ay that thp IKJ Tf i • • '" ^'"^^^ then the silicate of potLh would unite wWeLctiv.u^^^^^^ \' "J 'T''' sC^trof'LT^'Td^ ''''''' ^^'"p^""^ abovr:;!L"oT:T^^^^^^^^ \t trii /t -b : ' miv L 5l *w 'n excess, would form a kind of network througLut tL ^asl t' n?av be said, that a higher heat would overcome this diflicultv hv ihnr Zu hqui^Mng the silicate of soda; and this is really the plarnow use7'wirh t at iel^ but independent of the fact, that the mixed silicate of potash and soda would X' undergo a corresponding liquefaction, and, therefore, favour the separation of ThT silica e of soda; yet, as chemical union is impossible, from the very condition. !rn?J penment. even the most perfect mechanical mixture, under th^ great st ad v^nttes'of fu^ed together, mto, probably, one of the most antagonistic componmls that could ^ conceived, refracting and dispersing the rav of ii^ht in fiftv ,llC J.""*..™"!" •» 5-\,'«?" »*'pted into several continental angrefNererlM^^^^ ^T^A"'^ Ar^ley. Pellatt and Co. is a :„:tm'^re'„t"fo ^Snst'^h^tl .^ sl?c7tf SLt^lT^": and the mere mquirer into this branch of manufacture need go no fartSr ,„ it a neZ^ Z„ IJ'i^'? "' "•? T**"' ."l"' """ ^ »'='"'=™'' t>y "-e manipulation „? thil rn^a lerifl TOe host of others the effect is DositivplvH^r' 7 ' ^^ """^ Summerfield, and a cover the faults oVr^rlcfirnr^e^veli'tt"^,:^^^^^^^ -«^--t to ance ; and indeed, the glass koh-i-noor of Mr Pell at t di'pHved in hi' ^ ^'^'"^ ""-^^rZ: substituted for the real gem, shown in the main avemirw Zft thl 1 ^I'^i "V^?*.^ tion on the part of the million, or anv great los."of br li;rc?to Jp ' o7 "r a '''^''■ «o perfect is the imitation. Is it not tLo to be ^X^rZ:r.^^l^'::^:S^ mingling its constituents together? But we must turn from this glittering assortment and descend to a lower level, where we shall find Great Britain in (ii'Sgrace, and suffer- ing severely from comparison with a rival inferior in capital and natural resources, but England far into the shade. The prodi „. _,. ^„... „.„„^. .„„.,^ „, the Exhibition ; they have no competitors ; and we are in a condition to prove that chemistry has done this. Tlie plate-glass of Montluyon, too, adds to the defeat. In examin- ing the refractive aberrations of a mirror, the spectator will find his task facilitated by standing so that the rays of light from any geometrically shaped body fjill upon the glass, at an angle of 25° ; when, of course, they will be reflected towards his eye at the same angle. Now gazing intently on the figure in question— and which, in the Exhibition, may be one of the parallelograms formed by the rafters of the roof, let him gently move his head from one side to the other. If the glass be of English manufacture, he will imme- diately perceive a tumultuous moyement in the lines of the figure, as if this were subjected to an undulatory action, — the lines, before straight and parallel, become crooked and con- vergent in places, and minute objects lose entirely their outline and definition. In the case of the St. Gobain glass, shown in the French department, not))ing of this kind takes place. As it can serve no good purpose to dwell upon each individual example of imperfection, we refrain from entering further into the comparative merits of the British exhibitors. They are all surpassed by the French makers, both in respect to uniformity of composition and fineness of polish. The St. Gobain Company having had the good sense to place a number of small samples of their glass for the acceptance of those visitors who may feel an interest in the manufacture, we have selected and analyzed one of these little squares, and shall presently detail the result ; but our object in allu- ding to them here is, that glass-makers themselves may procure one of these specimens and contrast it with a like morsel of English plate-glass. If the two be laid side by sJile upon any moderately light-coloured ground, and a distant object, as a chimney for ex- ample, be subjected to reflection, it will be found, that whilst the French glass gives a clear sharp outline, the English reflects either two or more images in a hazv and imper- fect manner. There is no getting over this fact ; and therefore improvement is imperative. The mode of making plate-glass being, so to say, identical in the two countries, the dif- ference here remarked can arise from nothing else than a difference in composition. In France, as in England, the ingredients are mixed wnth some care, and introduced into a crucible, heated by a powerful furnace. These ingredients are sand or silica, carbonate of soda, and carbonate of lime, with perhaps a little ground felspar in some cases. The carbonate of soda is first attacked by the silica, and its carbonic acid driven off, whilst the remaining silica and carbonate of lime becomes imbedded in the vitrifving mass. As the heat increases, a more perfect fusion takes place ; and then tke carbonic acid of the carbonate of lime makes its way through the fused materials by which they are mechanically mingled together during the effervescence, which is technically termed the " boil ;"^ and, provided no after separation ensues from the process of " settling," the whole crucible or " pot" of glass will have a uniform composition, But, as we have seen, this depends altogether upon the relative proportion of the materials towards each other] for an excess of either one or other of the bases will destroy the homogeneous character of the whole, and introduce a plexus of stri.e. Now the plate-glass^'of St. Gobain is almost exactly an atomic compound, and consists of one atom of tlie trisilicate of soda and one atom of the trisilicate of lime, with a small percentage of alumina. The union is therefore complete ; and when it is remembered that the celebrated French chemist Gay Lussac, was regularly employed as an adviser to this company, and that his son' ' M. Jules Lussac, retains that appointment to this day, it is not very'surprisino- that our manufacturers are defeated in the article of plate-glass. Science must ever take the lead of prejudice and custom. The examination of English plate-glass fully corroborates the general result deduced from the action of light. There is no approach to an atomic arrangement. The principal constituent is trisilicate of soda, but variable quantities of lime, alumina, and even magnesia, exist in it. Potash is sometimes present, and oxide of iron is invariably so; but in not one single instance, out of 17 samples examined with great care, could so much as a surmise of the doctrine of combining proportions be gathered from the result of the analyses. Similarly fruitless was a research instituted upon flint- glass, both British and foreign. Of 35 samples analyzed, no satisfactory evidence could be adduced to favour the opinion that science had been a helpmate to industrj-, or was at all concerned in this branch of manufacture. There are. however, some points of vast interest associated with the practical working out of tliis matter. Potash la known to give a more brilliant and harder glass than soda, and alumina seems to tend in the sanoe direction. The Bohemian glass, so celebrated throughout Europe, is a glass of this description, and contains silicate of alumina, silicate of lime, and silicate of ' t 928 GLASS. potash, but not in chemical proportions. This (^lass is tht^rt^fnra utriat^A « ». fefinn w • '";r^""i *^^* .softness and liability to receive scratches which are so it has been demonstrated th.5, durinV^itrmcTtit't'e siUci It d 1 t^s'fo ttt' Z c^T of r 'T ^^'""'Vl "^ -^^^0 o^^^^^^^^^^ poKo ^oYpnll^b^e or tW ;i K ?!"^«"^^« 'f b^'-yta, and 112 of oxide of lead or li har^^e ^SupZe Ln tha the object 13 to employ carbonate of baryta for the first time here 6 aTms nr o7A carbonate of baryta, may be mixed and fused together with every Drosnect of nhMJnJn^ a good resul ; or 9 atoms of silica, 1 of carbonate of potash 1 TSnato of 3 and 1 of carbonate of baryta, might be tried without fplrnf f.^i carbonate of soda, orr'ad!l"r-^^T' V' «V^'^T^''^ ^^^oZLT'^T^^^^^^ or an additional atom of trisilicate of potash might be used For manv /I.rs n^t M. Dumas, now, perhaps, the first chemist in France, has been in the habif^?fl^ ' maw .ho wiu adSt thit hi, L isTurf:;rh',^„ ^f s.ioll\'„7i:a^;?;:i'-/4t To assist as far as we can in the attainment of this end we shall nrnrPPrl ♦« .i -u a simple means for the analysis of glass, which will enab e Ty persotrnos'e s^^^^ very trifling chemical skill, to detennine the composition oTL^^grJen^^^^^^^^^^^ in a comparatiyely short time. From the nature of the material^ LS neoestTv to divide the analysis into two distinct portions; one of which has fortTnhriff^ estimation of its alkaline ingredients, the other tha of the eaT hy metall c an,fe' *^^ matters Having heated a sufficient quantity of the sample in ^u^ must be suddenly thrown, whilst still hot, into a basin containing cold water In thi wlv ^ecomes cracked and flawed in all directions, so as to favour its reduction into powder When dry it must, therefore, be carefully ground in an agate or steel mo ?ar Sit has the appearance of fine flour. Nor is it a matter of indifference whXr this tales place m contact with water or not; for glass, in this extreme state of comminution readily gives up a part of its alkali to water; and hence, if ground in the pTeTence of that fluid, the resulting analysis would. prove incorrect. But we will sunnote fhnf I quantity of fine y powdered glass has been obtained as above indicated anTtTe.ntwn? of Its alkah IS desired ; then weigh out 100 grains of the glas^ndlreful y mix wit^^ t 200 grains of pure fluor spar in a similarly powdered rondit on PUoTtL 1^ T in a plat num or leaden vess& and pour ovei^ ft 500 ^rks of Zng ^^^^^^^ stirring the whole well together with a silver spoon but taking carP not t f '"" any portion of the materials. Xext, apply a 'eat of abo f ll° F^hr^n^^^ process draws to a conclusion, this may be raised as high as SOO^. When ill etllutn of gaseous fumes has ceased, water may be poured on the residuary ma-^s to thlexte of four or five ounces, and th6 mixture thrown on a filter After the rle^r fl?,: i i pa.ed through, a little more water must be added to the filterso a 'L Ith u Z whole of the soluble matter; these washings being joined to the original clear fl, J which consists of su phate of soda or potash, or bSth, with a quanti y "? s" plmte f lime, and perhaps also of magnesia and alumina. To this an excess of carbo te of ammonia must now be added, to admit of the ^enaratinn nf tho LJil 1 . • effected by filtration. The clear solution is next boilKTu t^o d^^e ^n^d S^e fduf IS heated red-hot for a minute or wo. This residue is the soda oV potash o both for! L?ppU""^^-?^ '"-^S? grains of the glass, but now united to sulphuric ach i. Havt^ ascertained its weight, the relative proportions of potash and sola may be found b? testing Its content of sulphuric acid with a barytic solution, and calculating te Lit by the well-known Archimedean equation; or by dissolving the mixed J t in a snia 1 quantity of water, and, after adding an excess of tartaric \ci ^ j It is obvious that the parallel horizontal movement may be effected by other mechani- cal means besides those adopted here, and the chief novelty claimed with respect to that movement, is its application to the purpose of carrying the index used in sewing and pointing leather gloves. ° Importation of leather gloves for home consumption ; and amount of duty in 1836. 1837. I 1836. 1837. 1,461,769. I 1,221,350. | £27,558. £22,923. GLOVE-SEWING. The following simple and ingenious apparatus, invented by an Enshshman, has been employed extensively in Paris, and has enabled its proprietor* to realize a handsome fortune. The French complain that "it has inundated the world with aloves, made of excellent quality, at 30 per cent, under their former wholesale 934 GLUE. .:i i< GLUE. 935 I * s s 1 prices." The instrument is shown in profile ready for ac tion in Jig. 734. It resembles an iron vice, having the upper portion of each jaw made of brass, and lipped with a kind of comb of the same metal. The teeth of this comb, only one twelfth of an inch long, are perfectly regular and equal. Change combs are provided for different styles of work. The vice A A is made fast to the edge of the bench or table b, of the proper height, by a thumb-screw c, armed with a cramp which lays hold of the wood. Of the two jaws com- • _ J - ^ , ,, ,, , , posing the machine, the one d is made fast to the loot a a, but the other e is moveable upon the solid base of the machine, by means of a hmge at the pomt r. At n is shown how the upper brass portion is ad- justed to the lower part made of iron ; the two being secured to each other by two stout screws. The comb, seen separately in fig, -JSe, is made fast to the upper end of each jaw, by the three screws nnn. Fig. 735 is a front view of the jaw mounted with its comb, to illustrate its construction. The lever k corresponds by the stout iron wire l, with a pedal pressed by the needle- woman s foot, whenever she wishes to separate the two jaws, in order to insert between them the parallel edges of leather to be sewed. The instant she lifts her foot, the two jaws join by the force of the spring g, which pushes the moveable jaw e against the stationary one d. The spring is made fast to the frame of the vice by the screw h. Atier putting the double edge to be sewed in its place, the woman passes her needle successively through aU the teeth of the comb, and is sure of makiiig a regular seam in every direcuon, provided she is careful to make the needle graze along the bottom of the notches. As soon as this piece is sewed, she presses down the pedal with her toes. Whereby the jaws start asunder, allowing her to introduce a new seam, and so in quick succession. ^ The comb may have any desired shape, straight or curved; and the teeth may be larger or smaller, according to the kind of work to be done. With this view, the combs mignt be changed as occasion requires; but it is more economical to have sets of vices ready mounted with combs of every requisite size and form. discov^rpH^t ^vJ^^'^'r ^'' ' ^'^7^^':^' p^'"")' i« one of the primitive earths, originally thie mhl^l h ?" ;"' V" ^"^^/"^ ^™"^^^^- ^' "^^y ^ ^^tracted from either of these minerals, by treating their powder successively with potash, with water and with muriatic acid. The solution by the latter, being evaporatecf to drV™ il to L di-el^d 7nt If I'i """^ ^^*f ''^; ^" P°"""^ '^'^^'^ «f ^'""^""i^ in exJess ito he liquid we form soluble muriate of ammonia, with insoluble carbonates of lime, chrome and "ron I^ also carbonate of glucina, which may be dissolved out from the rest by anTx(;esrof rarbo Lt^ciSd in twt^ ^"' t^^'ri'^ T-^' ^'^^ ^^"^'^ passTsThr^gh ^nd mt csTmnlo^l ll^^^y ^f ^ carbonate by boiling the liquid, which expefs ihe excels It n wWte ^^,.^f? ^"^' ^'y'^S, ^^dc^lcmmg the carbonate, pure glucina is obtained. water brtsohZ^n ^Z^'' f^^^^. '".'^'^ ^'^^ «^ * «™^t^'« ^«''&«. in«"l"ble in water but soluble m caustic potash and soda; as also, especially when it is a hydrate iombinr wk''4r2?r5 '' '"." T''^ ^^^^^ '^'"'^ gLinu^.^Jvhich lOo' pans rp;lLrn^n manlf^ctuTJs"^" '^ '"" *'^ '''''''' '' '' '^^ ^^ '« ^ ^--p'^'^^^ m nF^f^/7. V'^ ""T^ ^^"^ • ° *^^^P^ ^'^^ ^^^""^^ ^n^ar by M. Dumas, tin? ^7! d^ sta "P«n * «l«pi"g pavement^ where they are turned over by prongs two or three times a Say. The action of the lime dissolves the blood and certain soft parts, attacks the epidermis, and disposes the gelatinous matter to dissolve more readily. When the cleansed matters are dried, they may be packed in sacks or hogsheads, and transported to the glue manufactory at any distance. The principal substances of which glue is made are the parings of ox and other thick hides, which form the strongest article*, the refuse of the leather dresser ; both afford from 45 to 55 per cent, of glue. The tendons, and many other offals of slaughter-houses, also afford materials, though of an* inferior quality, for the purpose. The refuse of tanneries, such as the ears of oxen, calves, sheep, ?« '""■•^'"<"' f™'" '"% substances. water to this, we remove the vp,<«p1 frnm ti.^ «.« 1 ^ li. ,. V, » »""«« more ^i i* 1 u J M , . *^^»6i ii^ora tne nre. decant the liauor. fi ter it rwisa snl. phuretted hydrogen through it to spnamfo +!,/» 1^0 i *u iiV "4""^, "lur u, pass sui- the liauor as much as no,,iKlo « f^P I u • ^^'^' ^^^" ^^*^''" "♦'■^'''^' ^'"^ concentrate must TfinSlv evaporat^^^^^ ^"'"'"^. "P*'" *^^' ^'-^ndbath. What remains musi DC nnaiiy evaporated within the receiver of the a r pump. Glycerine thus nrP pared is a transparent liquid, without colour or smell, and^of a^syruprcon Le,"ce ^ f i has a very sweet taste. Its specific gravity is 1-27 at the temperatu e^ of 60- Whe„ hrown upon burning coals, it takes fire and burns like an oiL^ Water combines with It m almost all proportions; alcohol dissolves it rpa,i;i,r . «:/ • ".'V^'^ *^''"''''"^^ ^itli oxalic acid; and'acc^rding ioYo.el^'l^^X^,'),:^^ ^^^^ same way as it does starch Ferment or yeast does not affect it in any de^'rcS^ Its constituents are. carbon 40, hydrogen 9, oxygen 51. in 100 ^ ° The employment of glycerine as an application in the treatmeilt of deafness and also for other purposes as a medicinal agent, has given rise to enquiries on tiie subject, oa GOLD. 939 which account a few practical remarks may probably be interesting to some of our readers. Glycerine is one of the products of the saponification of fat oils. It is produced in large quantities in the soap manufactories in a very impure state, being contaminated with saline and empyreumatic matters, and having a very strong disagreeable odour. In order to obtain glycerine from th*is source, the residuary liquors are evaporated and treated with alcohol, which dissolves out the glycerine. The alcohol having been separated by evaporation, the glycerine is diluted with water, and boiled with animal charcoal. This process must be repeated several times, or until the result is sufficiently free from smell. It is, however, extremely difficult to obtain pure glycerine from this source, on account of the nature and condition of the ingredients usually employed in making soap, which it is almost impossible to deprive of rancid odour. The best method of obtaining glycerine for medicinal purposes is to evaporate the water used in making emplastrura plumbi. When the oil employed is fresh, and the process is carefully conducted, the result is easily made fit for use, and is almost without odour. Any lead with which it may be contaminated is separated by passing a stream of sulphuretted hydrogen through it when in a dilute state. The excess of gas escapes during the process of evaporation. If requisite, it may be boiled with animal charcoal, filtered, and evaporated. The specific gravity, when reduced to the proper consistence, is 1-27. It is now about twelve months since an announcement appeared in the medical journals, respecting a new cure for deafness, discovered by Mr. Yearsley. The remedy was reported to be perfectly simple, remarkably safe and very effectual. Several papers by Mr. Yearsley appeared in the Lancet during July and August, 1848; and from the statements therein contained, it appeared that the novelty consisted in the insertion of a piece of moistened cotton wool into the ear in a particular manner. In answer to the intimation that he " had not so fully described the modus operandi as to enable others to adopt it with more than a mere chance of success," Mr. Yearsley observes " in answer, I have only to say, that the experience of several years has taught me that it is impossible to convey to others, in words, such explicit directions as shall enable them to manipulate with any degree of certainty. In fact, it was on this account that I have so long held back from publishing any account of the remarkable fact I had observed in my practice." GNEISS, is the name of one of the great mountain formations, being reckoned the oldest of the stratified rocks. It is composed of the same substances as granite, viz. quartz, mica, and felspar. In gneiss, however, they are not in granular crystals, but in scales, so as to give the mass a slaty structure. It abounds in metallic treasures. GOLD. (Eng. and Germ. ; Or, Fr.) This metal is distinguished by its splendid yellow colour; its great density = 193 compared to water TO; its fusibility at the 32d degree of Wedgewood's pyrometer; its pre-eminent ductility and malleability, whence it can be beat into leaves only l-282,000th of an inch thick ; and its insolu- bility in any acid menstruum, except the mixture of muriatic and nitric acids, styled by the alchemists aqua regia, because gold was deemed by them to be the king of metals. Gold is found only in the metallic state, sometimes crystallized in the cube, and its derivative forms. It occurs also in threads of various sizes, twisted and interlaced into a chain of minute octahedral crystals ; as also in spangles or roundish grains, which when of a certain magnitude are called pepitas. The small grains are not fragments broken from a greater mass ; but they show by their flattened ovoid shape and their rounded outline that this is their original state. The spec. grav. of native gold varies from 13*3 to 17 '7. Humboldt states that the largest pepita known was one found in Peru weighing about 12 kilogi-ammes (26^ lbs. avoird.); but masses have been quoted in the province of Quito which weighed nearly four times as much. Another ore of g(»ld is the alloy with silver, or argental gold, the electrum of Pliny, so called from its amber shade. It seems to be a definite compound, containing in 100 parts, 64 of gold and 36 of silver. The mineral formations in which this metal occurs are the crystalline primitive rocks, the compact transition rocks, the trachytic and trap rocks, and alluvial grounds. It ftever predominates to such a degree as to constitute veins by itself. It is either disseminated, and as it were impasted in stony masses, or spread out in thin plates or grains on their surface, or, lastly, implanted in their cavities, under the shape of fila. ments or crystallized twigs. The minerals composing the veins are either quartz, calc- spar, or sulphate of baryta. Tlie ores that accompany the gold in tliese veins are chiefly iron pyrites, copper pyrites, galena, blende, and mispickel (arsenical pyrites). In the ores called auriferous pyrites, this metal occurs either in a visible or invisible form, and though invisible in the fresh pyrites becomes visible by its decomposition ; as the hydrated oxide of iron allows the native gold particles to shine forth ou their reddish- 940 GOLD. W II ThsZlZ^''7!?I^'Z Tu ^'■'"T "il^"^ °^^y *=«"^^^^"^^ ^-^^y ^^e five rr.Jionlh part nrort . r=c^ r Ra^'nelsberg in the Hartz. In that state it has been extracted with ^: sit anlltt tLtrtsufXeT'^ "^^^^"^^' ^^"^^"^^ ^^'^^ ''' '^'' ^^ ^^ ^^^ cr?f.i ^""T TT /^' P'-'^il've '''*^^' disseminated in small grains, spangles, and crjsta s. Brazil allords a remarkable example of this species of iold mine. Beds of VirRYca"wh^h"fo?mTrrr'''"^ '^^"' ^" ^^^ ^'-^^^ ^^ ''''^^^ '^ leagues beyond 45^ ^-t- ¥^^^- ^^?::;:l:^^S5.i:t!:.^ --^ --^^^^ - its tr^. ^n'l IT' T ?^'^''''^^ ^" *">* secondary formation, but pretty abundantly in ;r^ thl=^^tLs^^:;K:t^«^ '''''-' ^^^^^"^ ^"^^-^^^ -'^^ nvWt''/. n^rffn^' Tr' f """"."'y ^"'^ Transylvania, composed of tellurium, silver o^^rchne i'r r. I '' '"' and native gold, lie in masses or powerful veins in\ rock ?old ore of K^ii^Aprr^r^V^'^K^P" ^"^ordinate to it. Such is the locality of the !?ob,hTv ?Lr o? fh ^.'. ""^ Telk-ebanya, between Eperies and Tokay in Hungary, am ^enen 'n al^^^^ '[ ^^P"^*^^' Felsobanya, &c., in Transylvania ; an^arr'ange- of SnaxuaL of RP?I \\7^^^ ""T-^'r^ '"^ Equatorial America. The auriferous veins annZTZT' ."^^^ ^^"^^' ""^ Villalpando, are similar to those of Schemnitz in l"e rocks' thev ,r«?" "^ Vk ^"'^'.' P"^'''°"' '^' "^^"''^ ^^ ^^»« <^''' they include, and of dencTsof heV;,irnrv?^ «'^ mineralogists with he evi- minp! nf n^ -^ volcanic fire. Breislak and Hacquet have described the gold the" achy'es wi ^hTrm tT''' ^" ^^ "^^^^ ^' ^" ^"^^'"^ -'--• I'is certai^ fh^ alrnr u&a^^^ eluding gold, are now ?ran%. ^ana are rich fn tfr'' r' ^'''!'^'''' ^^'"^ them, which in Hun.ar/and the ";ichvte offh. Fnl ^ auriferous deposites; for gold has never been found in of Viver^ne. al of whf h''^ mountains of the mountains of the Vicentin, of those l^^f^Lri^.^^^^ !:rri;K.:::r^-ischia it trJ1.e^%7:roriSd'ent v^Sicr'"-^^^^^ ^^ '' ''' ^ ^^^^ ^^ ^^ Gold IS, however, much more common in the alluvial grounds than amon- the nrimJ t,ve and pyrogenous rocks just described. It is found disseminated u^er^he fon, of e'nedam-7n\h' '^''"°"'' a'-gillaceous, and ferruginous sands of certain p^aTns and riers t'^porir^y floodT """^""^^ '"^^^"' ^^ ^'^ ^^^^«" '' '^^ ^^^-^ -^ -^^er storms Inc hJlht^V'T" supposed that the gold found in the beds of rivers had been torn out pLn L h""? u""""- '^^ •'^"'"' ^"'^ P^''"^^'^^ '^^^'> ^hich they traverse. Some have ^redourmelai ' The" loM in'ihe' Tr ^^^'^^-^ «treams,'for the na.-ive heTof Z arthey gnJe aion^ ThL nn '""''' ^""7"*' '"^ '^"^ ^'"^""'^^ ^^'^^^^ed by the waters Guettard Rob ta/f* Sn T ' ^"-f t/'i ^' ^'St by Delius, and supported bv Deborn, D^ain?.nnt r ' \^' ^""'^ '' ^^""^^^ ^P^'^ J"st observations. 1. The soil of these plains contains, frequently, at a certain depth and in several spot, snan-les of Iold more gold after storms of rain upon the plains than in any other circumstances ^Tt happens almost always that gold is found among the sands of rivers on^V in a ver/'cil d,d uli mlt.'r'"' 7 '''?'^'"^, ""^^ "^"« ^^^- '^^^^ <=ease to artbrd gold; tlou%" source onhe r?eV^''V^ '"'^^^ ',^'"'^ ^^""^'^ ^^ ^'^""^ more abundan.ly ."r "he rn^'tol'^^^unro^wil't^hlpo" tITtI^'o ^^^ f''"" .?''Tl T '''' ^^^^^^ ^-- aiore and consenupntk fir ,V ^ ^ T ""<* a^^^ds gold only below the Lagu Ma-- river, as i. fl„ws a„K,„g Ae moluijrf S yrriUluT^oVoU ''l.:.''^ .^'"ioa of ,h« into the plain at Siejer, till its embouchure i"'hrDa„ube hslnih '^ "-r'^"" an.l are even rich enc.ush to be washed with profit "" """f^™"^ The greater part of the auriferous sands, in Euronp A«;. ar- ■ . are black or red, and onsequently ferru"iious ■ a r^™» b kI ^^""'' ""^ Ainerica geological no'iti.m or alluvial sold/ iMNaZne Un I rih^^^^^^^ crcamstance in th. ginous .rounds is due to the decon,po"u'rof ^S?^™, 3"' ^'if '■".IlL ""'■'^'^^'■™■ «.ad occurring in Hungary atoos. ahiSys in .be aeiglrhU'^f^he bel%?" -^.1^ GOLD. 941 and the petrified wood covered with gold grains, found buried at a de,,th of 55 yards in clay, in the mine of Vorospatak near Abrabanya in Transylvania, might lead us to pre- sume that the epoch of the formation of the auriferous alluvia is not remote from that of the lignites. The same association of nold ore and fossil wood occurs in South America, at Moco. Near the villasie of Lloro, have been discovered at a depth of 20 feel, large trunks of petrified trees, surrounded with fragments of trap rucks interspersed with spangles of gold and platinum. But the alluvial soil affords likewise all *he cha- racters of the basaltic rocks; thus in France, the Ceze and the Gardon, auriferous rivers, where they atl'ord most gold, flow over ground apparently derived from the destruction of the trap rocks, which occur in situ higher up the country. This fact had struck Reaumur, and this celebrated observer had remarked that the sand which more immediately accompanies the gold spangles in most rivets, and particularly in the Rhone and the Rhine, is composed, like that of Ceylon and Expailly, of black protoxyde of iron and small grains of rubies, corindon, hyacinth, &c. Titanium has been observed more recently. It has, lastly, been remarked that the gold of alluvial formations is purer than that extracted from rocks. Principal Gold Mines, Spain anciently possessed mines of gold in regular ^eins, especially in the province of Asturias ; but the richness of the American mines has made them to be neglected. The Tagus, and some other streams of that country, were said to roll over golden sands. France contains no workable gold mines ; but it presents in several of its rivers auri- ferous sands. There are some gold mines in Piedmont ; particularly the veins of aurife- rous pyrites of Macugnagna, at the foot of Monte Rosa, lying in a mountain of gneiss; and although they do not contain 10 or 11 grains of gold in a hundred weight, they have long defrayed the expense of working them. On the southern slope of the Pennine Alps, from the Simplon and Monte Rosa to the valley of Aoste, several auriferous districts and rivers occur. Such are the torrent Evenson, which has afforded much gold by washing; the Oreo, in its passage from the Pont to the Po; the reddish grounds over which this little river runs for several miles, and the hills in the neighborhood of Chivasso, contain gold spangles in considerable quantity. In the county of Wicklow, in Ireland, a quartzose and ferruginous sand was discovered not long aoo, containing many particles of gold, with pepit as or solid pieces, one of which weighed 22 ounces. No less than 1000 ounces of gold were collected. There a-e auriferous sands in some rivers of Switzerland, as the Reuss and the Aar. In Germaiij no mine of gold is worked, except in the territory of Salzburg, amid the chain of mountains which separates the Tyrol and Carinthia. The mines of Hungary and Transylvania are the only gold mines of any importance in Europe ; they are remarkable for their position, the peculiar metals that accompany them, and their product, estimated at about 1430 pounds avoird. annually. The principal ones are in Hungary. 1. Those of Konigsberg. The native gold is disseminatetl in ores of sulphuret of silver, which occur in small masses and in veins in a decompo>in2 feldspar rock, amid a conglomerate of pumice, constituting a portion of the Irachytic formation. 2. Those of Borson, Schemnitz. And, 3. of Felsobanya ; ores also of auriferous sulphu- ret of silver, occur in veins of sienite and greenstone porphyry. 4. Those of Telk©- banya, to the south of Kaschau, are in a deposile of auriferous pyrites amid trap rocks of the most recent formation. In Transylvania the gold mines occur m veins often of great magnitude, 6, 8, and some- times 40 yards thick. These veins have no side plates or wall stones, but abut without intermediate gangues at the primitive rock. They consist of carious quartz, ferriferous limestone, heavy spar, fluor spar, and sulphuret of silver. The mine of Kapnik deserves notice, where the gold is associated with orpiment, and that of Vcrospatak in eranite rocks ; those of Ofl'enbanya, Zaiatna, and Nagy-Ag, where it is associated with lellu num. The last is in a sienitic rock on the limits of the trachyte. In Sweden, the mine of Edelfors in Smoland may be mentioned, where the g(»ld occurs native and iu auriferous pyrites ; the veins are a brown quartz, in a mountain of foliated hornstone. In Siberia, iiative gold occurs in a hornstone at Schlangenberg or Zmcof, and at Zmeino gursk in the Altai mountains, accompanied with many other ores. The gold mine of Berezof in the Oural mountains has been long known, consisting of partially decomposed auriferous pyrites, disseminated in a vein of greasy quartz. About 1820, a very rich deposit of native gold was discovered on the eastern side of the Oural mountains, disseminated at some yards depth in an argillaceous loam, and accompanied with the debris of rocks which usually compose the auriferous alluvial soils, as greensttine, serpentine, protoxide of iron, corundum, me time over a bath of red hot tin, becomes brittle. The s^ame 'l inrhkpperl^^^ Inv \^'"" T'^T'/'T '^' ^''^"^"•■•y ^'^ ^^'^ "^^t«^- A two thousandth pa t of TxU inony, bismuth, or lead, destroys the ductility of -old. The tin may be eol rid of bv throwing some corrosive sublimate or nitre into a crucible, containin^^ the melte allov By the first acent, perchloride of tin is volatilized; by the second,%aL«/rof potash forms which is carried off in the resulting alkaline scorii. ' siavmite ol potash silver T^^^M ^^ ^^VP'"7^^f «^ amalgamation, contains commonly nothing but a little t^Z\ I ''!' '' "^"T^^^^ "''^ ^y "•^'■•^ ^^^'^^ ^^'ch leaves the gold untmiched but muTt be'ibsireS!"'^ "'' "^'"^ ^"' ^^^"^"^^ ^" ^^^ ^-^^ scale,'several precautions If the gold do not contain fully two thirds of its weight of silver, this metal beine thoroughly enve oped by the gold, is partially screened from^he action of the acTd When ever, therefore, it is known by a trial on a small scale, that the silver is much below thi, proportion, we must bring the alloy of gold and silver to that standard by addinl the re quelle quantity of the latter metal. This process is called quartation. " 1 his alloy IS then granulated or laminated ; and from twice to thrice its wei-ht of sul- phuric or nm.c ac.d is to be boiled upon it; and when it is judged that the solution has been pushed as far as possible by this first acid, it is decanted, and new acid ifpoured on Lastly, after having washed the gold, some sulphuric acid is to be boiled over it which snl'^r "f,^ '""'' ?' '?''^ ihousandth part of silver, which nitric acid alone could iot diV solve. Thus perfectly pure gold is obtained. The silver held in solution by the sulphuric or nitric acid is precipitated in the metallic state by copper, or in the state of chloride by sea-salt. See Parting meiaiiic Not only has the ratio between the value of gold and silver varied much in different ages of the world; but the ratio between these metals and the commodities they repre! sent has undergone variations, owing to the circumstances in which their mines have been successively placed; since they have always ponred a greater quantitvof the metals into the market than has been absorbed by use. This quantity has greLlv inc?^ased since the discovery of America, a period of little more than 300 years! The mines of that continent, rich, numerous, and easily worked, by augmenting the mass of gold and silver, necessarily lessened the value of these metals compared with that of the oLcts of commerce represented by them, so that everything else being equal, there is now required for purchasing the same quantity of commodities, much" more gold or silveT than was necessary m the reign of Henry VII., before the discovery of America This productiveness of the American mines has had an influence on those of .he ancient con- tinent; many of whose silver and goldmines have been abandoned, not becTuseX veins or auriferous sands are less rich than they were, but because their product no longer represents the value of human labor, and of the goods to be furnished in eturn for their exploitation. *-"cu lu icium In the 3d vol of the Mining Journal, p. 331, we have the following statement as to r .%n-."r ""^t" T"?r '"'/^'oTo" '" ^^ y'^''^ ^'^"^ I'^O to 1830, Mexico produced AllilAf 7''m '^ ^^'^T.' '"^ ^f '^J»>032/. of silver. Chili, 2,768,488/. of goTd and 1,822,924/. of Sliver. Buenos Avres, 4,024,895/ of eold anrt 97 iso ^tq; "r i Russia 3,703,743/. of gold, and 1,502,98U. of 's.rver!' xfuC^SSo'^lnS'trHit "; 47 millions per annum. o tumj,, «• The following table shows what proportion the product of the mines of America bears to that of the mines of the ancient continent. GOLD. 94T Tabu of the Quantities of Gold which may be considered as having been brought into the European Market, every Year on an Average, from 1790 to 1802. Continent. Gold. Ancient Continent. Ibe. Armr. Asia: - . - - . . . Siberia .... . . 3740 Africa - . - - . . . 3300 Europe : - ^ ^ Hungary . - - s • 1430 Salzbourg .... . 165 Austrian States - - - . "^ Hartz and Hessia . Saxony .... . Norway ... . p 165 Sweden ... . . France ... . . Spain, &c. ... Total of the Ancient Continent New Continent. 'J 8800 North America .... . 2860 South America - . . . Spanish dominions - . 22,000 Brazil - - - - Total of the New Continent - • 15,400 • • 40,260 The mines of America have sent into Europe three and a half times more gold, nmi twelve times more silver, than those of the ancient continent. The total quantity of silver was to that of gold in the ratio of 55 to 1 ; a very different ratio from that whiek holds really in the value of these two metals, which is in Europe as 1 to 15. Thm difference depends upon several causes, which cannot be investigated here at length; but it may be stated that gold, by its rarity and price, being much less employed in the arts than silver, the demand for it is also much less ; and this cause is sufficient t* lower its price much beneath what it would have been, if it had followed the ratio of its quantity compared to that of silver. Thus also bismuth, tin, &c., though much rarer than silver, are, nevertheless, very inferior in price to it. Before the discovery of America, the value of gold was not so distant from that of silver, because since that en silver has been distributed in Europe in a far greater proportion than gold. In Asia the proportion is now actually only 1 to 1 1 or 12 ; the product of the gold mines in that quarter, being not so much below that of the silver mines as in the rest of the world. The total annual production of Gold at present has been estimated as follows. From the ancient Spanish colonies of America - Brazil _ - - . Europe and Asiatic Russia The Indian Archipelago Africa .... 10,400 kilogramme! 600 6,200 4,700 14,000? 35,900=36 tons nearlf without taking into account the quantity of gold now extracted from silver. Gold has less aflUnity for oxygen than any other metal. When alone, it cannot be oxydized by any degree of heat with contact of air, although in combination with other oxydized bodies, it may pass into the state of an oxyde, and be even vitrified. The pnr- ple smoke into which gold leaf is converted by an electric discharge is not an oxyde, for it is equally formed when the discharge is made through it in hydrogen gas. There are two oxydes of gold ; the first or protoxyde is a green powder, which may be ob- tained by pouring, in the cold, a solution of potash into a solution of the metallic chloride. It is not durable, but soon changes in the menstruum into metallic goM, 948 GOLD. '1 •nd peroxyde. Its constituents are 96- 13 metal, and 3-87 oxygen. The peroxyde is best prepared by adding magnesia to a solution of the metallic chloride; washing the precipi- tate with water till this no longer takes a yellow tint from muriatic acid; then digesting strong nitric acid upon the residuum, which removes the magnesia, and leaves the per- oxyde in the form of a black or dark brown powder, which seems to partake more of the properties of a metallic acid than a base. It contains 10-77 per cent, of oxygen. For the curious combination of gold and tin, called the Purple Pkecipitate of Cassius, see this article, and Pigments Vitbifiable. Gold beating. — This is the art of reducing gold to extremely thin leaves, by beating with a hammer. The processes employed for this purpose may be applied to other metals, as silver, platinum, and copper. Under tin, zinc, &c., we shall mention such modifications of the processes as these metals require to reduce them o thin leaves. The Romans used to gild the ceilings and walls of their apartments ; and Pliny tells us, that from an ounce of gold forming a plate of 4 fingers square, about 600 leaves of the same area were hammered. At the present day, a piece of gold is extended so as to cover a space 651,590 times greater than its primary surface when cast. The gold employed in this art ought to be of the finest standard. Alloy hardens gold, and renders it less malleable ; so that the fraudulent tradesman who should attempt to de- base the gold, would expose himself to much greater loss in the operations, than he could derive of profit from the alloy. Four principal operations constitute the art of gold beating. 1. The casting of the gold ingots. 2. The hammering. 3. The lamination ; and 4, the beating. 1. The gold is melted in a crucible along with a iittle borax. When it has become -iquid enough, it is {wtired out into the ingot-moulds previously heated, and greased on the inside. The ingot is taken out and annealed in hot ashes, which both soften it and free it from grease. The moulds are made of cast iron, with a somewhat concave in- ternal surface, to compensate for the greater contraction of the central parts of the metal in cooling than the edges. The ingots weigh about 2 ounces each, and are J of an inch broad. 2. The forging. — When the ingot is cold, the French gold-beaters hammer it out on a mass of steel 4 inches long and 3 broad. The hammer for this purpose is called the forging hammer. It weighs about 3 pounds, with a head at one end and a wedge at the other, the head presenting a square face of 1^ inches. Its handle is 6 inches long. The workman reduces the ingot to the thickness of J of an inch at most ; and during this op- eration he anneals it whenever its substance becomes hard and apt to crack. The English gold-beaters omit this process of hammering. 3. The lamination. — The rollers employed for this purpose should be of a most per- fectly cylindrical figure, a polished surface, and so powerful as not to bend or yield in the operation. The ultimate excellence of the gold leaf depends very much on the precision with which the riband is extended in the rolling press. The laminating machine repre- sented under the article Mint, is an excellent pattern for this purpose. The gold-beater desires to have a riband of such thinness that a square inch of it will weigh 65 grains. Frequent annealings are requisite during the lamination. 4. Beating. — The riband of gold being thus prepared uniform, the gold-beater cuts it with shears into small squares of an inch each, having previously divided it with com- passes, so that the pieces may be of as equal weight as possible. These squares are piled over each other in parcels of 150, with a piece of fine calf-skin vellum interposed between each, and about 20 extra vellums at the top and bottom. These vellum leaves are about 4 inches square, on whose centre lie the gold laminae of an inch square. This packet is kept together by being thrust into a case of strong parchment open at the ends, so as to form a belt or band, whose open sides are covered in by a second case drawn over the packet at right angles to the first. Thus the packet becomes sufiiciently compact to bear beating with a hammer of 15 or 16 pounds weight, having a circular face nearly 4 inches diameter, and somewhat convex, whereby it strikes the centre of the packet most forcibly, and thus squeezes out the plates laterally. The beating is performed on a very strong bench or stool framed to receive a heavy block of marble, about 9 inches square on the surface, enclosed upon every side by W(K)d- work, except the front where a leather apron is attached, which the workman lays be- fore him to preserve any fragments of gold that may fall out of the packet. The hammer is short-handled, and is managed by the workman with one hand ; who strikes fairly on the middle of the packet, frequently turning it over to beat both sides alike ; a feat dex- terously done in the interval of two strokes, so as not to lose a blow. The packet is oc- casionally bent or rolled between the hands, to loosen the leaves and secure the ready extension of the gold ; or it is taken to pieces to examine the gold, and to shift the cen- tral leaves to the outside, and vice versa, that every thing may be equalized. Whenever the gold plates have extended, under this treatment, to nearly the size of the vellum, Ibey are removed from the packet, and cut into four equal squares by a knife. Thev GOLD. 949 I are thus reduced to nearly the same size as at first, and are again made up into packets and enclosed as before, with this difljerence, that skins prepared from ox-gut ure nov interposed between each gold leaf instead of vellum. The second course of beating is performed with a smaller hammer, about 10 pounds in weight, and is continued till the leaves are extended to the size of the skins. During this period the packet must be often folded, to render the gold as loose as possible between the membranes ; otherwise tlje leaves are easily chafed and broken. They are once more spread on a cushion, and sub- divided into four square pieces by means of two pieces of cane cut to very sharp edges, and fixed down transversely on a board. This rectangular cross being applied on each leaf, with slight pressure, divides it into four equal portions. These are next made up into a third packet of convenient thickness, and finally hammered out to the area of fine gold leaf, whose averase size is from 3 to 3^ inches square. The leaves will now have ob- tained an area 192 times greater than the plates before the hammering begun. As these were originally an inch square, and 75 of them weighed an ounce (= 6^ X 75 = 487|), the surface of the finished leaves will be 192 X 75 = 14,400 square inches, or 100 square feet per ounce troy. This is by no means the ultimate degree of attenuation, for an ounce may be hammered so as to cover 160 square feel ; but the waste incident in this case, fiom the number of broken leaves, and the increase and nicety of the labor, make this an unprofitable refinement; while the gilder finds such thin leaves to make less durable and satisfactory work. The finished leaves of gold are put up in small books made of single leaves of soft paper, rubbed over with red chalk to prevent adhesion between them. Before putting the leaves in these books, however, they ure lifted one by one with a delicate yair of pin- cers out of the finishing packet, and spread out on a leather cushion by blowing them flat down. They are then cut to one size, by a sharp-edge square moulding of cane, glued on a flat board. When this square-framed edge is pressed upon the gold, it cuts it to the desired size and shape. Each book commonly contains 25 gold leaves. % I shall now describe some peculiarities of the French practice of gold beating. The workman cuts the laminated ribands of an inch broad into portions an inch and a half long. These are called quartiers. He takes 24 of them, which he places exactly over each other, so as to form a thickness of about an inch, the riband being | of a line, or Jj of an inch thick ; and he beats them together on the steel slab with the round face (panne) of the hammer, so as to stretch them truly out into the square form. He begins by extending the substance towards the edges, thereafter advancing towards the middle ; he then does as much on the other side, and finally hammers the centre. By repeating this mode of beating as often as necessary, he reduces at once all the quartiers (squares) of the same packet, till none of them is thicker than a leaf of gray paper, and of the size of a square of 2 inches each side. When the quartiers are brought to this state, the workman takes 56 of them, which he piles over each other, and with which he forms the first packet (caucher) in the man- ner already described ; only two leaves of vellum are interposed between each gold leaf. The empty leaves of vellum at the top and bottom of the packet are called emplures. They are 4 inches square, as well as the parchment pieces. The packet thus prepared forms a rectangular parallelopiped ; it is enclosed in two sheaths, composed each of several leaves of parchment applied to each, and glued at the two sides, forming a bag open at either end. The block of black marble is a foot square at top, and 18 inches deep, and is framed as above described. The hammer used for beating the first packet is called the flat, or the enlarging hammer; its head is round, about 5 inches in diameter, and very slightly convex. It is 6 inches high, and tapers gradually from its head to the other extremity, which gives it the form of a hexagonal truncated pyramid. It weighs 14 or 15 pounds. The French gold-beaters employ, besides this hammer, three others of the same form ; namely, 1. The commencing hammer^ which weighs 6 or 7 pounds, has a head 4 inches in diameter, and is more convex than the former. 2. The spreading hammer (marleau d chasser) ; its head is two inches diameter, more convex than the last, and weighs only 4 or 5 pounds. 3. The finishing hammer ; it weighs 12 or 13 pounds, has a head fopr inches diameter, and is the most convex of all. The beatinc processes do not differ essentially from the English described above. The vellum is rubbed over with fine calcined Paris plaster, with a hare's foot. The skin of the gold-beater is a pellicle separated from the outer surface of ox-gut ; but before being employed for this purpose, it must undergo two preparations. 1. It is sweated, in order to expel any grease it may contain. With this view, each piece of membrane is placed between two leaves of white paper ; several of these pairs are piled over each other, and struck strongly with a hammer, which drives the grease from the gut into the paper. 2. A body is given to the pieces of gut ; that is, they are moistened with an infasioD 950 GOLD. of cinnamon, nutmeg, and other warm and aromatic ingredients, in order to preserve them ; an operation repeated aAer they have been dried in the air. When the leaves of skin ai-edry, they are put in a press, and are now ready for use. After the parchment^ vellum, and gut membrane have been a good deal hammered, they become unfit for work, till they are restored to proper flexibility, by being placed leaf by leaf between leaves of wliite paper, moistened sometimes with vinegar, at others with white wine. They are left in this predicament for 3 or 4 hours, under compression of a plank loaded with weights. When they have imbibed the proper humidity, they are put between leaves of parchment 12 inches square, and beat in that situation for a whole day. They are then rubbed over with fine calcined gypsum, as the vellum was originally. The gut-skin is apt to contract damp in standing, and is therefore dried before being used. The average thickness of common gold leaf is of an inch. 282000 The art of Gilding, — This art consists in covering bodies with a thin coat of gold ; which may be done either by mechanical or chemical means. The mechanical mode is the application of gold leaf or gold powder to various surfaces, and their fixation by va- rious means. Thus gold may be applied to wood, plaster, pasteboard, leather ; and to metals, such as silver, copper, iron, tin, and bronze; so that gilding, geneially speaking, includes several arts, exercised by very dififerent classes of tradesmen. I. Mechanical Gilding. — Oil gilding is the first method under this head, as oil is the fluid most generally used in the operation of this mechanical art. The following process has been much extolled at Paris. 1. A coat of impression is to be given first of all, namely, a coat of white lead paint, made with drying linseed oil, containing very little oil of turpentine. 2. Calcined ceruse is to be ground very well with unboiled linseed oil, and tempered with essence of turpentine, in proportion as it is laid on. Three or four coats of this hard tint are to be applied evenly and dryly on the ornaments and the parts wlych are to ^ most carefully gilded. 3. The Gold color is then to be smoothly applied. This is merely the dregs of the colors, ground and tempered with oil, which remain in the little dish in which painters 3lean their brushes. This substance is extremely rich and gluey ; after being ground ap, and passed through fine linen cloth, it forms the ground for gol(^ leaf. 4. When the gold color is dry enough to catch hold of the Icni" gold, this is spread on the cushion, cut into pieces, and carefully applied with the palette knife, pressed down with cotton, and in the small ornaments with a fine brush. 5. If the gildings be for outside exposure, as balconies, gratings, statues, &c., they must not be varnished, as simple oil gilding stands belter ; for when it is varnished, a bright sun-beam, acting after heavy rain, gives the gilding a jagged appearance. When the objects are inside ones, a coat of spirit varnish may be passed over the gold leaf, then a glow from the gilder's chafing dish may be given, and finally a coat of oil varnish. The workman who causes the chafing dish to glide in front of the varnished surface, must avoid stopping for an instant opposite any point, otherwise he would cause the varnish to boil and blister. This heat brings out the whole transparency of the varnish and lustre of the gold. Oil Gilding is employed, with varnish polish, upon equipages, mirror- frames, and other furniture. The following method is employed by eminent gilders at Paris. 1. White lead, with half its weight of yellow ochre, and a little litharge, are sepa- rately ground very fine ; and the whole is then tempered with linseed oil, thinned with essence of turpentine, and applied in an evenly coat, called impression. 2. When this coat is quite dry, several coats of the hard tint are given, even so many as 10 or 12, should the surface require it, for smoothing and filling up the pores. These coats are given daily, leaving them to dry in the interval in a warm sunny exposure. 3. When the work is perfectly dry, it is first softened down with pumice slone and water, afterwards with worsted cloth and very finely powdered pumice, till the hard tint give no reflection, and be smooth as glass. 4. With a camel's hair brush, there must be given lightly and with a gentle heat, from 4 to 5 coats at least, and even sometimes double that number, of fine lac varnish. 5. When these are dry, the grounds of the panels and the sculptures must be first polished" with shave-grass (de laprlle) ; and next with putty of tin and tripoli, tempered with water, applied with woollen cloth ; by which the varnish is polished till it shines like a mirror. 6. The work thus polished is carried into a hot place, free from dust, where it receives very lightly and smoothly a thin coat of gold color, mu?h softened down. This coat is passed over it with a clean soft brush, and the thinner it is the better. 7. Whenever the gold color is dry enough to take the gold, which is known by laying the back of the hand on a corner of the frame work, the gilding is begun and finished as usual. 8. The gold is smoothed oflf with a very soft bmsh, one of camel's hair, for example, of three fingers' breadth ; after which it is left to dry for several days. GOLD. 951 I' I 9. It is then varnished with a spirit of wine varnish ; which »s treated with the chafing dish as above described. 10. When this varnish is dry, two or three coats of cepal or oil varnish are applied, at intervals of two days. 11. Finally, the panels are polished with a worsted cloth, imbued with tripoli and water, and lustre is given by friction with the palm of the hand, previously softened with a little olive oil, taking care not to rub off" the gold. In this courttry, burnished gilding is practised by first giving a ground of size whiting, in several successive coats ; next applying gilding size ; and then the gold leaf, which is burnished down with agate, or a dog's tooth. Gilding in distemper of the French, is the same as our burnished gilding. Their pro- cess seems to be very elaborate, and the best consists of 17 operations ; each of them said to be essential. 1. Encollage, or the glue coat. To a decoction of wormwood and garlic in water, strained through a cloth, a little common salt and some vinegar are added. This com- position, as being destructive of worms in wood, is mixed with as much good glue ; and the mixture is spread in a hot state, with a brush of boar's hair. When plaster or marble is to be gilded, the salt must be left out of the above composition, as it is apt to attract hu- midity in damp places, and to come out as a white powder on the gilding. But the salt is indispensable for wood. The first glue coating is made thinner than the second. 2. White preparation. This consists in covering the above surface with 8, 10, or 12 coats of Spanish white, mixed up with strong size, each well worked on with the brush, and in some measure incorporated with the preceding coat, to prevent their peeling oflf in scales. 3. Stopping up the pores, with thick whiting and glue, and smoothing the surface with dog-skin. 4. Polishing the surface with pumice-stone and very cold water. 5. Reparation; in which a skilful artist retouches the whole. 6. Cleansing ; with a damp linen rag, and then a soft sponge. 7. Preler. This is rubbing with horse's tail (shave-grass) the parts to be yellowed, in order to make them softer. 8. Yellowing. With this view yellow ochre is carefully ground in water, and mixed with transparent colorless size. The thinner part of this mixture is applied hot over the white surface with a fine brush, which gives it a fine yellow hue. 9. Ungraining consists in rubbing the whole work with shave-grass, to remove any granular appearance. 10. Coat of assiette ; trencher coat. This is the composition on which the gold is to be laid. It is composed of Armenian bole, 1 pound ; bloodstone (hematite), 2 ounces ; and as much ealcna ; each separately ground in water. The whole are then mixed to- gether, and ground up with about a spoonful of olive oil. The assiette well made and ap- plied gives beauty to the gilding. The assiette is tempered with a white sheep-skin glue, very clear and well strained. This mixture is heated .nd applied in three successive coats, with a very fine long-haired brush. 11. Rubbing, with a piece of dry, clean linen cloth; except the parts to be burnished, vvfaich are to receive other two coats of assiette tempered with glue. 12. Gilding. The surface, being damped with cold water (iced in summer), has then the gold leaf applied to it. The hollow grounds must always be gilded before the pro- minent parts. Water is dexterously applied by a soft brush, immediately behind the gold leaf, before laying it down, which makes it lie smoother. Any excess of water is then removed with a dry brush. 13. Burnishing with bloodstone. 14. Deadening. This consists in passing a thin coat of glue, slightly warmed, over the parts that are not to be burnished. 15. Mending ; that is, moistening any broken points with a brush, and applying bits of gold leaf to them. 16. The vermeil coat. Vermeil is a liquid which gives lustre and fire to the gold ; and makes it resemble or moulu. It is composed as follows : 2 ounces of annotto, 1 ounce of gamboge, 1 ounce of vermilion, half an ounce of dragon's blood, 2 ounces of salt of tartar, and 18 grains of saflTron, are boiled in a litre (2 pints English) of water, over a slow fire, till the liquid be reduced to a fourth. The whole is then passed through a silk or muslin sieve. A little of this is made to glide lightly over the gold, with a very soft brush. 17. Repassage is passing over the dead surfaces a second coat of deadening glue, which must be hotter than the first. This finishes the work, and gives it strength. Leaf gilding, on paper or vellum, is done by giving them a coat of gum water or fine size, applying the gokl leaf ere the surfaces be hard dry, and burnishing with agate. 962 GOLD. Gold Jetteringf on bound books, is given without size, by laying the gold leaf on the leather, and imprinting it with hot brass types. The edges of /he leaves of books are gilded while they are in the press, where they have been cut smooth, by applying a solution of isinglass in spirits, and laying on the gold 'when the edges are in a proper state of dryness. The French workmen employ a ground of Arnenian bole, mixed with powdered sugar-candy, by means of white of egg. This ground is laid very thin upon the edges, after fine size or gum water has been applied ; and when the ground is dry it is rubbed smooth with a wet rag, which moistens it suffi- ciently to take the gold. Japanner's gilding is done by sprinkling or daubing with wash leather, some gold pow- jer, over an oil sized surface, mixed with oil of turpentine. This gi\es the appearance of frosted gold. The gold powder may be obtained, either by precipitating gold from its solution in aqua regia by a solution of pure sulphate of iron, or by evaporating away the mercury from some gold amalgam. yi. Chemical gildingj or the application of gold by chemical affinity to metallic sur faces. A compound of copper with one seventh of brass is the best metal for gilding on ; cop- per by itself being too soft and dark colored. Ordinary bras?, however, answers very well. We shall describe the process of wash gilding, with M. D'Arcel*s late improve- ments, now generally adopted in Paris. Wash gilding consists in applying evenly an amalgam of gold to the surface of a cop- per alloy, and dissipating the mercury with heat, so as to leave the gold film fixed. The surface is afterwards burnished or deadened at pleasure. The gold ought to be quite pure, and laminated to facilitate its combination with the mercury ; which should also be pure. Preparation of the amalgam. After weighing the fine gold, the workman puts it in a crucible, and as soon as this becomes faintly red, he pours in the requisite quantity of mercury; which is about 8 to 1 of gold. He stirs up the mixture with an iron rod, bent hookwise at the end, leaving the crucible on the fire till he perceives that all ihe gold is dissolved. He then pours the amalgam into a small earthen dish containing water, washes it with care, and squeezes out of it with his fingers all the running mercury that he can. The amalgam that now remains on the sloping sides of the vessel is so pasty as to preserve the impression of the fingers. When this is squeezed in a shamoy leather bag, it gives up much mercury; and remains an amalgam, consisting of about 33 of mer- cury, and 57 of gold, in 100 parts. The mercury which passes through the bag, under the pressure of the fingers, holds a good deal of gold in solution ; and is employed in ma- king fresh amalgam. Preparation of the mercurial solution. The amalgam of gold is applied to brass, through the intervention of pure nitric acid, holding in solution a little mercury. 100 parts of mercury, and 110 parts by weight of pure nitric acid, specific gravity 1*33, are to be put into a glass matrass. On the application of a gentle heat the mercury dis- solves with the disengagement of fumes of nitrous gas, which must be allowed to escape into the chimney. This solution is to be diluted with about 25 times its weight of pure water, and bottled up for use. 1. .Annealing. — The workman anneals the piece of bronze after it has come out of the hands of the turner and engraver. He sets it among burning charcoal, or rather peats, which have a more equal and lively flame ; covering it quite up, so that it may be oxydized as little as possible, and taking care that the thin parts of the piece do not become hotter than the thicker. This operation is done in a dark room, and when he sees the piece of a cherry red color, he removes the fuel from about it, lifts it out with long tongs, and sets it to cool slowly in the air. 2. The decapage. — ^The object of this process is to clear the surface from the coat of oxyde which may have formed upon it. The piece is plunged into a bucket filled with extremely dilute sulphuric acid ; it is left there long enough to allow the coat of oxyde to be dissolved, or at least loosened ; and it is then rubbed with a hard brush. When the piece becomes perfectly bright, it is washed and dried. Its surface may however be still a little variegated ; and the piece is therefore dipped in nitric acid, specific gravity 1*33, and afterwards rubbed with a long-haired brush. The addition of a litile common salt to the dilute sulphuric acid would probably save the use of nitric acid, which is so apt to produce a new coat of oxyde. It is finally made quite dry (after washing in pure water), by being rubbed well with tanners' dry bark, saw-dust, or bran. The surface should now appear somewhat de-polished ; for when it is very smooth, the gold does not adhere to well. Application of ihe amalgam. — ^Thc gilder's scratch-brush or pencil, made with fine brass wire, is to be dipped into the solution of nitrate of mercury, and is then to be drawn over a lump of gold amalgam, laid on the sloping side of an earthen vessel, after which it is to be applied to the surface of the brass. This process is to be GOLD. 953 repeated, dipping the brush into the solution, and drawing it over the amalgam, till the whole surface to be gilded is coated with its just proportion of gold. The piece is then washed in a body of water, dried, and put to the fire to volatilize the mercury. If one coat of gilding be insufficient, the piece is washed over anew with amalgam, and the op- eration recommenced till the work prove satisfactory. 4. Volatilization, of the mercury. — Whenever the piece is well coated with amalgam, the gilder exposes it to glowing charcoal, turning it about, and heating it by degrees to the proper point ; he then withdraws it from the fire, lifts it with long pincers, and, seizing it in his left hand, protected by a stufifed glove, he turns it over in every direc- tion, rubbing and striking it all the while with a long-haired brush, in order to equalize the amalgam. He now restores the piece to the fire, and treats it in the same way till the mercury be entirely volatilized, which he recognises by the hissing sound of a drop of water let fall on it. During this time he repairs the defective spots, taking care to I'olatilize the mercury very slowly. The piece, when thoroughly coaled with gold, is washed, and scrubbed well with a brush in water acidulated with vinegar. If the piece is to have some parts burnished, and others dead, the parts to be burnished are covered with a mixture of Spanish white, bruised sugar-candy, and gum •'•ssolved in water. This operation is called in French epargner (protecting). When the gilder has protected the burnished points, he dries the piece, and carries the heat high enough to expel the little mercury which might still remain on it. He then plunges it, while still a little hot, in water acidulated with sulphuric acid, washes it, dries it, and gives it the burnish. 5. The burnish is given by rubbing the piece with burnishers of hematite (blood- stone). The workman dips his burnisher in water sharpened with vinegar, and rubs the piece always in the same direction backwards and forwards, till it exhibits a fine polish, and a complete metallic lustre. He then washes it in cold water, dries it with fine linen cloth, and concludes the operation by drying it slowly on a grating placed above a chafing dish of burning charcoal. 6. The deadening is given as follows. The piece, covered with the protection on those parts that are to be burnished, is attached with an iron wire to the end of an iron rod, and is heated strongly so as to give a brown hue to the epargne by its partial carbon- ization. The gilded piece assumes thus a fine tint of gold; and is next coated over with a mixture of sea salt, nitre, and alum, fused in the water of crystallization of the latter salt. The piece is now restored to the fire, and heated till the saline crust which covers it becomes homogeneous, nearly transparent, and enters into true fusion. It is then taken from the fire and suddenly plunged into cold water, which separates the saline crust, car- rying away even the coat ot epargne. The piece is lastly passed through very weak nitrle acid, washed in a great body of water, and dried by exposure either to the air, over a drying stove, or with clean linen cloths. 7. Of or-moulu color. — When it is desired to put a piece of gilded bronze into or- moulu color, it must be less scrubbed with the scratch-brush than usual, and made to come back again by heating it more strongly than if it were to be deadened, and allowing it then to cool a little. The or-moulu coloring is a mixture of hematite, alum, and sea salt. This mixture is to be thinned with vinegar, and applied with a brush so as to cover the gilded brass, with reserve of the burnished parts. The piece is then put on glowing coals, urged a liitle by the bellows, and allowed to heat till the color begins to blacken. The piece ought to be so hot that water sprinkled on it may cause a hissing noise. It is then taken from the fire, plunged into cold water, washed, and next rubbed with a brush dipped in vinegar, if the piece be smooth, but if it be chased, weak nitric acid must be used. In either case, it must be finally washed in a body of pure water, and dried over a gentle fire. 8. Of red gold color. — To give this hue, the piece, after being coated with amalgam and heated, is in this hot state to be suspended by an iron wire, and tempered with the composition known under the name of gilder's wax ; made with yellow wax, red ochre, verdigris, and alum. In this state it is presented to the flame of a wood fire, is heated strongly, and the combustion of its coating is favored by throwing some drops of the wax mixture into the burning fuel. It is now turned round and round over the fire, so that the flame may act equally. When all the wax of the coloring is burned away, and when the flame is extinguished, the piece is to be plunged in water, washed, afid scrubbed with the scratch-brush and pure vinegar. If the color is not beautiful, and quite equal in shade, the piece is coated with verdigris dissolved in vinegar, dried over a gentle fire, plunged in water, and scrubbed with pure vinegar, or even with a little weak nitric acid if the piece exhibit too dark a li le. It is now washed, burnished, washed anew, wiped with linen cloth, and finally dried over a gentle fire. The f»llowing is the outline of a complete gilding factory, as now fitted up at Paris. Fig. 738. Front elevation and plan of a complete gilding workshop. 954 GOLD. GRADUATOR. 955 p. Fainace «^ appelf or draught, serving at the same time to heat the deadening pao (p0iUni au mat). 788 P ^^^^^ ■"J^S^^ r. Ashpit of this furnace. N. Chimney of this furnace constructed of bricks, as far as the contraction of tiie great chimney s of the forge, and which is termiDated by a summit pipe rising 2 or 3 yards above this contraction. B. Forge for annealing the pieces of bronze; for drying the gilded pieces, &c. c. Chimney of communication between the annealing forge b, and the space d below the forge. This chimney serves to carry the noxious fumes into the great vent of the factory. u. Bucket for the brightening operation. A. Forge for passing the amalgam over the piece. E. Shelf for the brushing operations. E E. Coal cellarets. 0. Forge for the deadening process. G. Furnace for the same. M. An opening into the furnace of appd, by which vapors may be let off from any ope- ration by taking out the plug at m. 1. Cask in which the pieces of gilded brass are plunged for the deadening process. The vapors rising thence are carried up the general chimney. J J. Casement with glass panes, which serves to contract the opening of the hearths, without obstructing the view. The casement may be rendered moveable to admit lai^er objects. H H. Curtains of coarse cotton cloth, for closing at pleasure, in whole or part, one or several of the forges or hearths, and for quickening the current of air in the places whem the curtains are not drawn Q. Opening above the draught furnace, which serves for the heating of the poejon a% mat (deadening pan). Gilding on polished iron and steel. — If a nearly neutral solution of gold in muriatic acid be mixed with sulphuric ether, and agitated,' the ether will take up the cold, and float above the denser acid. When this auriferous ether is applied by a hair pencil to brightly polished iron or steel, the ether flies off, and the gold adheres. It must be fixed by polishing with the burnisher. This gilding is not very rich or durable. In fact, the affinity between gold and iron is feeble, compared to that between gold and copper or •ilrer. But polished iron, steel, and copper, may be gilded with heat, by gold leaf. They are first heated till the iron takes a bluish tint, and till the copper has attained to a like temperature; a first coat of gold leaf is now applied, which is pressed gently down with a burnisher, and then exposed to a gentle heat. Several leaves either single or double are thus applied in succession, and the last is burnished down cold. Cold gilding. — Sixty grains of fine gold and 12 of rose copper are to be dissolved in two ounces of aqua resia. When the solution is completed, it is to be dropped on clean linen rag?, of such bulk as to absorb all the liquid. They are then dried, and burned in- to ashes. These ashes contain the gold in powder. When a piece is to be eilded, after subjecting it to the preliminary operations of soft- ening or annealing and brightening, it is rubbed with a moistened cork, dipped in the above powder, till the surface seems to be sufficiently gilded. Large works are there- after burnished with pieces of hematite, and small ones with steel burnishers, along with soap water. In gilding small articles, as buttons, with amalgam, a portion of this is taken equivalent to the work to be done, and some nitrate of mercury solution is added to it in a wooden trough ; the whole articles are now put in, and well worked about with a hard brush, till their surfaces are equably coated. They are then washed, dried, and put altogether iRto an iron frying-pan, and healed till the mercury begins to fly off, when they are turned out into a cap, in which they are tossed and well stirred about with a painter's brush. The operation must be repeated several times for a strong gilding. The surfaces are hnally brightened by brushing them along with small beer or ale grounds. Gold wire is formed by drawmg a cylindrical rod of the metal, as pure as may be, through a series of holes punched in an iron plate, diminishing progressively in size. The gold, as it is drawn through, becomes hardened by the operation, and requires frequent annealing. Gold thread, or spun gold, is a flatted silver-gilt wire, wrapped or laid over a thread of yellow silk, by twisting with a wheel and iron bobbins. By the aid of a mechanism like the Braiding Machine, a number of threads may thus be twisted at once by one master wheel. The principal nicety consists in so regulating the movements that the successive volutions of the flatted wire on each thread may just touch one another, and form a continuous covering. The French silver for gilding is said to be alloyed with 5 or 6 pennyweights, and ours with 12 pennyweights of copper in the pound troy. The gold is applied in leaves of greater or less thickness, according to the quahly of the gilt wire. The smallest proportion formerly allowed in this country by act of parliament, was 100 grains of gold to one pound, or 5760 grains of silver ; but more or less may now be used. The silver rod is encased in the gold leaf, and the compound cylinder is then drawn into round wire down to a certain size, which is afterwards flatted in a rolling mill such as is described under Mint. The liquor employed by goldsmiths to bring out a rich color upon the surface of their trinkets, is made by dissolving 1 part of sea salt, 1 part of alum, 2 parts of nitre, in 3 or 4 of water. This pickle or sauce, as it is called, takes up not only the copper alloy, but a notable quantity of gold ; the total amount of which in the Austrian empire, has been estimated annually at 47,000 francs. To recover this gold, the liquor is diluted with at least twice its bulk of boiling water ; and a solution of very pure green sulphate of iron is poured into it. The precipitate of gold is washed upon a filler, dried, and purified by melting in a crucible along with a mixture of equal parts of nitre and borax. Gold refining. — The following process has been patented as a foreign invention by Mr. W. E. Newton in Januarv, 1851. It consists, 1,, in reducing argentiferous or any other gold bullion to a granulated, or spongy, or disintegrated molecular condition by fusion therewith of zinc, or some other metal baser than silver, and the subsequent removal of the zinc by dilute sulphuric or other acid ; that is, the reducing of the gold bullion to a state to allow of the re- moval by acids of the silver and other impurities contained therein, so as to fit it for coinage and other purposes without quartation with silver or any other interineduite process. And 2., in pulverizing by grinding or concussion gold bullion, rendered brittle by union with lead, solder, or other suitable metal, the silver and other impurities being removed by acids in this as in the preceding case, and recovered from the acid solution by any of the known chemical means. Tliis operation, if properly conducted, will produce fine ductile gold in a state of great purity ; that is, containing from 985 to 995 per cent, of pure gold. GONG-GONG ; or tam-tam of the Chinese ; a kind of cymbal made of a copper alloy, described towards the end of the article Copper. GONIOMETER, is the name of a little instrument made either on mechanical or optical principles, for measuring the angles of crystals. It is indispensable to the mine- ralogist. GRADUATOR, called by its contriver M. Wagenmann, Essighilder, which means, in German, vinegar-maker, is represented in fig. 739. It is an oaken tub, 5^ feet high, Z^ feet wide at top, and 3 at bottom, set upon wooden beams, which raise its bottom 966 GRAUWACKE. about U inches from the floor. At a distance of 16 inches above the bottom, the tub is pierced with a horizontal row of 8 equidistant round holes, of an inch in diameter. At 6 inches beneath the mouth of the tub, a thick beech-wood hoop is made fast to the inner surface, which supports a circular oaken shelf, leaving a space round its edge of IJ^ inches, which is stuffed water-tight with hemp or tow. In this shelf, 400 holes at least must be bored, about i of an inch in diameter, and 1^ inches apart; and each of these must be loosely filled with a piece of packthread, or cotton wick, which serves to filter the liquid slowly downwards. 3ln the same shelf there are likewise four larger holes of 1^ inches diameter, and 18 inches apart, each of which re- ceives air-tight a glass tube 3 or 4 inches long, having its ends projecting above and below the shelf. These tubes serve to allow the air that enters by the 8 circumferential holes, to circulate freely through the graduator. ITie mouth of the tube is covered with a wooden lid, in whose middle is a hole for the insertion of a funnel, when the liquor of acetification requires to be iniroduced. One inch above the bottom, a hole is bored for receiving a syphon-formed discharge pipe, whose upper curvature stands one inch below the level of the holes in the side of the tub, to prevent the liquor from rising: so high as to overflow through them. The syphon is so bent as to retain a body of liqiior 12 inches deep above the bottom of the tub, and to allow the ex cess only to escape into the subjacent receiver. In the upper part of the graduator, but under the shelf, the bulb of a thermometer is inserted through the side, some way into the interior, having a scale exteriorly. The whole capacity of the cask from the bottom up to within one inch of the perforated shelf, is to be filled with thin shavings of beech wood, grape stalks, or birch twigs, previously imbued with vinegar. The manner of using this simple apparatus is described under Acetic Acid. GRANITE is a compound rock, essentially composed of quartz, feldspar, and mica, each in granular crystals. It constitutes the lowest of the geological formations, and therefore has been supposed to serve as a base to all ihe rest. It is the most durable material for buildins, as many of the ancient Egyptian monuments testify. The obelisk in the place of Saint Jean de Lateran at Rome, which was quarried at Syene, under the reian of Zetus. king of Thebes, 1300 years before the Christian era j and the one in the place of Saint Pierre, also at Rome, consecrated to the Sun by a son of Sesostris, have resisted the weather for fully 3000 years. On the other hand there are many granites, especially those in which feldspar predominates, which crack and crumble down in the course of a few years. In the same mountain, or even in the same quarry, granites of very different qualities as to soundness and durability occur. Some of the granites of Cornwall and Limousin readily resolve themselves into a white kaolin or argillaceous matter, from which pottery and porcelain are made. Granite, when some time dug out of the quarry, becomes refractory, and diflScult to cut. When this rock is intended to be worked it should be kept under water ; and that variety ought to be selected which contains least feldspar, and in which the quartz or gray crys- tals predominate. , . GRANULATION is the process by which metals are reduced to minute grains. It is effected by pouring them, in a melted state, through an iron cullender pierced with small holes, into a body of water ; or directly upon a bundle of twigs immersed in water. In this way copper is granulated into bean shot, and silver alloys are granulated preparatory to Parting * which see. GRAPHITE {Plomb'agiMyFr, ; Reissblei, Germ.) is a mineral substance of a lead or iron gray color, a n.etallic lustre, soft to the touch, and staining the fingers with a lead gray hue. Spec. grav. 2-08 to 2-45. It is easily scratched, or cut with a steel edge, and displays the metallic lustre in its interior. Burns with great difficulty in the outward flame of the blow-pipe. It consists of carbon in a peculiar state of aegreaation, with an extremely minute and apparently accidental impregnation of iron. Graphite, called also plumbaso and black lead, occurs in gneiss, mica slate, and their subordinate clay slates and lime sUrnes ; in the form of masses, veins, and kidney-shaped disseminated pieces; as also in the transition slate, as at Borrodale in Cumberland, where the most precious deposite exists, both in reference to extent and quality, for making pencils. It has been found also among the coal strata, as near Cumnock in Ayrshire. This substance is em- ployed for counteracting friction between rubbing surfaces of wood or metal, for making crucibles and portable furnaces, for giving a gloss to the surface of cast iion, &c. See Plumbago, for some remarks concerning the Cumberland mine. GRAUWACKE, or GREYWACKE, is a rock formation, composed of pieces of quartz, flinty slate, feldspar, and clay slate, cemented by a clay-slate basis; the pieces varying id size from small grains to a hen's egg. GREEN PAINTS. 957 GRAY DYE. (Teinture grise, Fr. ; Graufdrbe, Germ.) The gray dyes, in theii numerous shades, are merely various tints of black, in a more or less diluted state, from the deepest to the lightest hue. , /. i, u The dyeing materials are essentially the tannic and gallic acid of galls or other astringents, along with the sulphate or acetate of iron, and occasionally wine stone. Ash gray is given for 30 pounds of woollen stuff, by one pound of gall nuts, ^ 'h. of wine stone' (crude tartar), and 2^ lbs. of sulphate of iron. The galls and the wine stone being boiled with from 70 to 80 pounds of water, the stuff is to be turned through the de- coction at a boiling heal for half an hour, then taken out, when the bath being re- freshed with cold water, the copperas is to be added, and, as soon as it is dissolved, the Stuff is to be put in and fully dyed. Or, for 36 pounds of wool ; 2 pounds of tartar, h pound of galls, 3 pounds of sumach, and 2 pounds of sulphate of iron are to be taken. The tartar being dissolved in 80 pounds of boiling water, the wool is to be turned through the solution for half an hour, and then taken out. The copper being filled up to its former level with fresh water, the decoction of the galls and sumach is to be p<.ured in, and the wool boiled for half an hour in the bath. The wool is then taken out, while the copperas is being added and dissolved ; after which it is replaced in the bath, and dyed gray with a gentle heat. If the gray is to have a yellow cast, instead of the tartar, its own weight of alum is to be taken ; instead of the galls, one pound of old fustic ; instead of the copperas, | of a pound of Salizburg vitriol, which consists, in 22| parts, of 17 of sulphate of iron, and 5| of sulphate of copper; then proceed as above directed. Or the stuff may be first stained in a bath of fustic, next in a weak bath of galls with a little alum ; then the wool being Uken out, a little vitriol (common or Saltzburg) is to be put in, previously dis.solved ia a decoction of logwood ; and in this bath the dye is completed. Pearl gray is produced by passing the stuff first through a decoction of sumach and logwood (2 lbs. of the former to ^jne of the latter), afterwards through a dilute solution of sulphate or acetate of iron ; and finishing it in a weak bath of weld containing a little alum. Mouse-gray is obtained, when with the same proportions as for ash-gray, a small quantity of alum is introduced. For several other shades, as tawny-gray, iron-gray, and slate-gray, the stuff must re- ceive a previous blue ground by dipping it in the indigo vat ; then it is passed first through a boiling bath of sumach with galls, and lastly through the jame bath at a lower temperature after it has received the proper quantity of solution of iron. For dyeing silk gray, fustet, logwood, sumach, and elder-tree bark, are employed instead of galls. Archil and annotto are frequently used to soften and beautify the tint. The mode of producing gray dyes upon cotton has been sufficiently explained in the articles Calico Printing and Dyeing. GREEN DYE is produced by the mixture of a blue and yellow dye, the blue being first applied. See Dyeing; as also Blue and Yellow Dyes, and Calico Printing. . • v • GREEN PAINTS. (Couleurs vertes^ Fr. ; Grune pigmented Germ.) Green, which is so common a color in the vegetable kingdom, is very rare in the mineral. There is only one metal, copper, which affords in its combinations the various shades of green in general use. The other metals capable of protlucing this color are, chromium in its prot- oxyde, nickel in its hydrated oxyde, as well as its salts, the seleniate, arseniate, and sul- phate ; and titanium in its prussiate. Green pigments are prepared also by the mixture of yellows and blues ; as, for ex- ample, the green of Rinman and of Gellert, obtained by the mixture of cobalt blue, and flowers of zinc ; that of Barth, made with yellow lake, Prussian blue, and clay ; but these paints seldom appear in the market, because the greens are generally extemporaneous preparations of the artists. * . . Mountain green consists of the hydrate, oxyde, or carbonate of copper, either factitious, or as found in nature. Bremen or Brunswick green is a mixture of carbonate of copper with chalk or lime, and sometimes a little magnesia or ammonia. It is improved by an admixture of white lead. It may be prepared by adding ammonia to a mixed solution of sulphate of copper and alum. Frise green is prepared with sulphate of copper and sal ammoniac. Miltis green is an arseniate of copper ; made by mixing a solution of acetate or sul- phate of copper with arsenite of potash. It is in fact Scheele's green. Sap green is the inspissated juice of buckthorn berries. These are allowed to fer- ment for 8 days in a tub, then put in a press, adding a little alum to the juice, and con centrated by gentle evaporation. It is lastly put up in pigs' bladders, where it becomes dry and lard 958 GUANO. GUANO. 959 Schweinfurt green ; sec Scuwkinfukt. Verona green is merely a variety of the mineral called green earth GREEN VITRIOL is sulphate of iron in green crystals. GROW AN. The name given by the Cornish miners to granite, and to rocks of like structure. . , i GUAIAC, {Gaiac, Fr. ; Chuijaharz, Germ.) is a resin which exudes from the trunk of the Gtiaiacum officinaUy a tree which grows in the West India islands. It comes to us in large green idi-brown, semi-transparent lumps, having a conchoidal or splintery fracture, brittle and easy to pulverize. It has an aromatic smell, a bitterish, acrid taste, melts with heat, and has a spec grav. of from 1-20 to 122. It consists of 67-88 carbon; 7 05 hydrogen; and 25'07 oxygen; and contains two different resins, the one of which is soluble in all proportions in ammonia, and the other forms, with water of ammonia, a tarry consistenced mixture. It is soluble in alkaline lyes, in al- cohol, incompletely in ether, still less so in oil of turpentine, and not at all in fat oils. Its chief use is in medicine. GUANO. This extraordinary excremenlitious deposite of certain sea-fowls, which occurs in immense quantities upon some parts of the coasts of Peru, Bolivia, and Africa, has lately become an object of great commercial enterprise, and of intense interest to our agricultural world. Four or five years ago it was exhibited and talked of merely as a natural curiosity. No one could then have imagined that in a short period it would be imported from the coasts of the Pacific in such abundance, and at such a moderate price, as to cheer by its fertilizing powers the languid and depressed spirits of the farmers throughout the United Kingdom. Such, however, is now the result, as attested by the concurring reports of almost all the agricultural societies of Great Britain and Ireland. No less than 28,500 tons of guano have been already imported from Peru and Bolivia, 1,500 from Chili, and 8,000 from Africa, altogether 38,000 tons, while more is on the way. The store of it, laid up from time immemorial in the above localities, seems to be quite inexhaustible ; especially since it is receiving constant accessions from myriads of cormorants, cranes, &c. Having been much occupied w^ith the chemical analyses of guano during the last two years for Messrs. Gibbs, of London, and Messrs. Myers, of Liverpool, who are the co-agents of the Peruvian and Bolivian governments, I have enjoyed favorable oppor- tunities of examining samples of every description, and hope to show that many of the analyses of guano hitherto published fiave been made upon specimens not in their nor- mal or sound state, like the best imported by the above houses from Chincha and Bolivia, but 'n a certain state of cremacausis and decay. Huano, in the language of Peru, signifies dung; a word spelt by the Spaniards guano. The natives have employed it as a manure from the remotest ages, and have by its means given fertility to the otherwise unproductive sandy soils along their coasts. While Peru was governed by its native incas, the buds were protected from violence by severe laws. The ptnishment of death was decreed to persons who dared to land on the guanifer- ous islands during the breeding period of the birds, and to all persons who destroyed them at any time. Overseers were appointed by the government to take care of the guano districts, and to assign to each claimant his due share of the precious dung. The celebrated Baron Von Humboldt first brought specimens to Europe in 1804, which he sent for examination to Foureroy, Vauquelin, and Klaproth, the best analytical chem- ists of the day; and he spoke of it in the following terms : " The guano is deposited m layers of 50 or 60 feet thick upon the granite of many of the South sea islands oft the coast of Peru. During 300 years the coast birds have deposited guano only a few lines in thickness. This shows how great must have been the number of birds, and how many centuries must have passed over in order to form the present guano-beds." The strata have undergone many changes, according to the length of tune they have been deposited. Here and there they are covered with silicious sand, and have thu* been protected from the influence of the weather ; but in other places, they have lain open to the action of light, air, and water, which have produced important changes upon them. Fresh guano is of a whitish or very pale drab color, but it becomes pro- gressively browner and browner by the joint influence of the above three atmospheri- cal agents. Only one guano examined by Foureroy and Vauquelin was found to con- tain a fourth of its weight of uric acid combined with ammonia, whence that appears to have been well selected by Baron Von Humboldt. They also found phosphates of ammonia, of lime, with urate and oxalate of ammonia, and some other const.Aients of little value in agriculture. Klaproth's analysis reported 16 per cent, of urate of ammo- nia, no less than 12-75 of oxalate of lime, 10 of phosphate of lime, 32 of clay and sand, jvith 28-75 of water and indeterminate organic matter. From the great proportion of 2lay and sand, Klaproth's sample of guano was obviously not genuine. I have met ▼ith no specimen of Peruvian guano that contained any appreciable quantity of clay, and none that contained above 4 or 5 per cent, of silicious sand. To Mr. Bland, of the firm of Messrs. Myers and Co., I am indebted for the following valuable information : — , • v j The Chincha islands, which afford the best Peruvian guano, are three in number, and lie in one line from north to south, about half a mile apart. Each island is from five to six miles in circumference, and consists of granite covered with guano in some places to a hei<'ht of 200 feet, in successive horizontal strata, each stratum being from 3 to 10 inches thick, and varying in color from light to dark brown. No earthy matter whatever is mixed with this vast mass of excrement. At Mr. Bland's visit to these islands in 1842, he observed a perpendicular surface of upward of 100 feet of perfectly uniform aspect from top to bottom. In some parts of these islands, however, the deposite does not exceed 3 or 4 feet in thickness. In several places, where the surface of the guano is 100 feet or more above the level of the sea, it is strewed here and there with masses of granite, like those from the Alpine mountains, which are met with on the slopes of the Jura chain. These seem to indicate an ancient formation for the guano, and ter- raqueous convulsions since that period. No such granite masses are found imbedded within the guano, but only skeletons of birds. . ^ ^ , r • The good preservation of the Chincha guano is to be ascribed to the absence or ram ; which rarelv, if ever, falls between the latitude of W south, where these islands lie, about 10 miles from the main land, and the latitude of Paquica, on the island cf Bo- livia in 21° S. L. By far the soundest cargoes of guano which I have analysed have come from Chincha and Bolivia. Beyond these limits of latitude where rain falls in greater or less abundance, the guano is of less value— and what has been imported from Chili has been found by me far advanced in decay— most of the ammonia and azotised animal substances having been decomposed by moisture, and dissipated in the air (by the eremacausis of Liebig), leaving phosphate of lime largely to predominate along with effete organic matter. The range of the American coast from which the guano is taken must therefore be well considered ; and should not extend much beyond the Chincha islands as the northern limit, and Paquica, in Bolivia, as the southern. The relative estimation of ^uano and nitrate of soda among the Peruvians is well shown by the following fact communicated to me by Mr. Bland : " N^ar the coast of Peru, about 45 miles from Iquique (the shipping port of guano) there is the chief deposite of nitrate of soda. The farmers, who collect and purify this natural product, carry it to the place of shipment, and always require to be paid in return with an equivalent . quantity of guano, with which they manure their land, to the exclusion of the far cheaper nitrate of soda. We can not be surprised at this preference, when we learn that in the valley of Chancay, about 40 miles distant from Lima, the soil produces, when farmed with irrigation in the natural way, a return upon maize of only 15 for 1 ; whereas, with the aid of guano, it produces 500 for 1 ! Hence the Peruvian proverb: Huano, though no saint, works many miracles. In the pamphlet recently published by Messrs. Gibbs and Myers, -.ntitled « Peruvian and Bolivian Guano, its nature, properties, and results," we have a ver>- interesting view of the best established facts with regard to its operation and effects upon «A'ery variety of soil, and in every variety of circumstance, as ascertained by th«^ most intelligent agriculturists of the United Kingdom. The general conclusion that may t>e fairly deduced from the whole evidence is, that good guano will, under judicious application, increase the crops of grain, turnips, potatoes, and grass, by about 33 per cent. ; and with its present price of 10/. per ton, at a cost considerably under the aver- age cost of all other manures, whether farm-yard dung and composts, or artificial com- pounds. Guano is, moreover, peculiarly adapted to horticultural and floricultural im- provement, by its relative cleanliness and facility of application. The following observations upon guano, by Dr. Von Martins, of Munich, addressed to the agricultural society of Bavaria, deserve attention. Among animal manures, says he, it clearly claims the first place. It is uncommonly rich in ammoniacal salts, which act very favorable on vegetation. The ease with which these salts are decom- posed, and exhale their ammonia into the air, is by him assigned as the reason why plants manured with guano generally present early in the morning accumulations of dew on the points of their leaves. The guano absorbs the atmospheric vapor, as well as carbonic acid ; whereby it becomes so valuable a manure in dry barren regions. If we compare guano with other excrementitious manures, we shall find it far preferable to those afforded by man or other mammalia, which do not generally contain more than 20 per cent, of food that can be appropriated by plants. It is therefore five tiines better than night-soil, and also veiy superior to the French poudrette, which, being dried night- soil, loses, through putrefaction and evaporation, the greater proportion of its ammonia- cal elements. In birds, the excretions both of the kidneys and intestines are contained in the cloaca ; wherebv the volatile elements of the former get combined with Uiemore fixed components of the latter. The guano is also a richer manure, on account of its being produced bv sea-fowl, which live entirely on fish, without admixture of vegetable 960 GUANO. 1 II matter. The exposure also of the guano as soon as deposited to the heat of a tropical dun, in a rainless climate, prevents the components from fermenting, and mummifies them, so to speak, immediately into a concrete substance not susceptible of decomposition till it gets moisture ; whereas the dung of our dove-cotes suffers a considerable loss by exposure to our humid atmosphere. But in their action on vegetation, and in their chemical composition, these two bird excrements are analogous. Davy found in fresh dove-cote manure 23 parts in 100 soluble in water, which yielded abundance of car- bonate of ammonia by distillation, and left carbonaceous matter, saline matter, princi- pally common salt, and carbonate of lime as a residuum. Pigeons' dung readily fer- ments, but after fermentation afforded only 8 per cent, of soluble matter, which gave proportionably less carbonate of ammonia in distillation than the dung recently voided. Dr. Von Martins proceeds to compare the proportion of soluble salts in guano and pigeons' dung, and thinks that by that comparison alone he can establish the superiority of the former ; but he should have considered that the insoluble urate of ammonia, which is so powerful and copious a constituent of good guano, and is present in much smaller proportion in pigeons' dung, is sufficient of itself to turn the balance greatly in favor of the Peruvian manure. His general estimate, however, that the manuring power of genuine guano is four times greater than that of pigeons' dung, is probably not ^ride of the truth. Besides the above-mentioned constituents, guano derives no small por- tion of its fertilizing virtue from the great store of phosphoric acid which it contains, in various states of saline combination, with lime, magnesia, and ammonia. Of all the principles furnished to plants by the soil, the phosphates are, according to Liebig, the most important. They afford, so to speak, the bones and sinews of vegetable bodies, while ammonia supplies them with their indispensable element, azote. Their carbon, hydrogen, and oxygen, are derived from the air and water. Those products of vegetation which are most nutritious to man and herbiverous animals, such as bread-corn, beans, peas, and lentils, contain the largest proportion of phosphates. The ashes of these vegetable substances afford no alkaline carbonates. A soil in which phosphates are not present, is totally incapable of producing the above cereals. Agreeably to these views, Liebig believes that the importation of 1 cwt. of guano is equivalent to the importation of 8 cwts. of wheal ; so that 1 cwt. of that manure assumes, with due culture, the form of 8 cwts. of substantial foodtfor man. Since all these testimonies concur to place this remarkable excrementitious product in fuch high estimation, it becomes a paramount duty of the chemist to investigate its com- position, and to discover certain means of distinguishing what maybe termed the sound or normal state of guano, from the decomposed, decayed, and effete condition. The analysis by Fourcroy and Vauquelin of a sample of guano presented to them by Baron Von Humboldt, gave the following composition in 100 parts : — Urate of ammonia - - - Oxalate of ammonia - - - Oxalate of lime - - . Phosphate of ammonia Phosphate of ammonia and magnesia - Sulphate of potash - - - soaa Sol ammoniac - Phosphate of lime Clay and sand Water and organic matters 9-0 10-6 7-0 6-0 5*6 3-3 4-2 14-3 4-7 32-3 til How different are these constituents from those assigned by Klaproth — a no less skil- ful analyst than the French chemists ! and how much this difference shows not only the complexity of the substance, but its very variable nature ! The general results of an analysis by Professor Johnston, published in his paper on guano, in the 3d part of the 2d vol. of the Journal of the Royal Agricultural Society of England, are as follows : — Ammonia - - - - - Uric acid ---_-_- Water and carbonic and oxalic acids, &c., expelled by a red heat Common salt, with a little sulphate and phosphate of soda Phosphate of lime, &c. - - - . 00-0 The specimen of guano represented by this analysis must have been (&i advanced in decomposition, as shown by the very scanty portion of uric acid ; and musv have been ©riginally impure {.spurious ?) from the large proportion of conmion salt, of which I ha\ e GUANO. 961 not found above 4 or 6 per cent, in any of the genuine guanos which I have had occasioR to analyze. In another sample, Professor Johnston found 44-4 of phosphate of lime, with a little phosphate of magnesia, and carbonate of lime. These results resemble, to a certain degree, those which I have obtained in analyzing several samples of Chilian and African guanos, especially in the predominance of the earthy phosphates. The pro- portion of ammonia which can be extracted by the action of hydrate of soda and quick- lime, at an elevated temperature, is the surest criterion of the soundness of the guano ; for by this process we obtain not only the readi/ formed ammonia, from its several saline compounds, but also the ammonia producible from its uric acid, and undefined animal matter. These two latter quantities have been hitherto too little regarded by most analysts, though they constitute the most durable fund of azote for the nutrition of plants. Uric acid, and urate of ammonia, which contains 10-llths of uric acid, being both nearly insoluble in water, and fixed at ordinary temperatures, continue to give out progressively to plants in the soil, the azote, of which they contain fully one-third of their weight. Under the influence of oxygen and a certain temperature, uric acid passes through a very remarkable series of transformation ; producing allantoin, urea, and oxalic acid, which eventually becomes carbonic acid. These changes are produci- ble immediately by the action of boiling water and peroxide of lead. From these metamorphoses, we can readily understand how much oxalate of ammonia and of lime is reported in many analyses of guano, though none, I believe, is to be found in the normal state, as it is occasionally imported from the Chincha Islands and Bolivia ; nor were any oxalates found in the dung of the gannet, as analyzed by Dr. Wollaston, or of the sea eagle, according to the following analysis of Coindet: ammonia, 921 per cent.; uric acid, 84-65 ; phosphate of lime, 61 3=1 GO. The Peruvian sea-fowl, by feeding exclusively on fish, would seem to swallow a large proportion of earthy phosphates ; since, in the purest guano that has come in my way, I have found these salts to amount to from 10 to 15 per cent '^ Dr. Von Martius proposes to use the degree of solubility of the guano in water as a good criterion of its quality ; but this is a most fallacious test. Sound guano contains from 15 to 25 per cent, of insoluble urate of ammonia; nearly as much undefined animal matter, along with from 15 to 20 of earthy phosphates, leaving no more than 50 or 55 per cent of soluble matter, exclusive of moisture ; whereas decayed guano yields often 60 or 70 per cent of its weight to water, in consequence of the uric acid and animal matter being wasted away, and the large portion of moisture in it, the latter amounting very often to from 25 to 35 per cent The good Peruvian guano does not lose more than from 7 to 9 per cent, by drying, even at a heat of 212° Fahr. ; and this loss necessarily includes a little ammonia. Each analysis of guano executed for the information of the farmer should exliibit definitely and accurately to at least 1 per cent: — 1. The proportion of actual ammonia. 2. The proportion of ammonia producible also from the uric acid and azotized animal matter present ; and which may be called the potential ammonia. This is a most valuable product, which is, however, to be obtained only from well-preserved drt guano. 3. The proportion of uric acid, to which, if 1 10th of the weight be added, the quan- tity of urate of ammonia is given. 4. The proportion of the phosphates of lime and magnesia. 5. The proportion of fixed alkaline salts, distinguishing the potash from the soda salts ; the former being more valuable, and less readily obtainable, than the latter can be ' y the use of common salt. Wheat, peas, rye, and potatoes, require for their success- ful cultivation, a soil containing alkaline salts, especially those of potash. 6. The proportion of sandy or other earthy matter, which, in genuine guano care- fully collected, never exceeds 2 per cent, and that is silica. ' 7. The proportion of water, separable by the heat of 212=^ F. The farmer should never purchase guano except its composition in the preceding particulars be warranted by the analysis of a competent chemist. He should cork up m a bottle a half-pound sample of each kind of guano that he buys ; and if his crop shall disappoint reasonable expectation, he should cause the samples to be analyzed; and should the result not correspond to the analysis exhibited at the sale, he is fairly entitled to damages for the loss of his labor, rent, crop, &c. The necessity of follow- ing this advice will appear on considering the delusive if not utterly false analyses, under which cargoes of guano have been too often sold. In a recent case which came under my cognizance, in consequence of having been employed professionally to analyze the identical cargo, I found the guano to be nearly rotten and efiete; containing aUo- gether only 2.^ per cent, of ammonia, | per cent, of urate of ammonia, nearly f) of sea gait, 24 of water, and 45| of earthy phosphates. Now, this large cargo, of many hundred tons, fetched a high price at a public sale, under the exhibition of the follow- ing analysis by a chemist of some note : — 962 GUAJNO. Urate of ammonia, ammoniacal salts, and decayed animal matter 17'4 Phosphate of lime, phosphate of magnesia, and oxalate of lime - 48- 1 Fixed alkaline salts -------_. jo-g Earthy and stony matter -------- 1.4 Moisture -------... 22*3 100-0 The purchasers, I was told by the broker, bought it readily under a conviction that the guano contained 17*4 of ammonia, though the proportion of ammonia is not stated, bat merely mystified, and adroitly confounded with the decayed animal matter. By the following hypothetical analysis, much guano has been well sold : — " Bone earth, 35 ; lithic acid, &c., 15 ; carbonate of ammonia, 14 ; organic matter, 36 = 100." I am quite certain that no sample of guano can contain 14 per cent, of carbonate of ammonia— a very volatile salt. We sWl see presently the state of combination in which the ammonia exists. It may contain at the utmost 4 or 5 per cent, of the carbo- nate ; but such guano must have been acted upon powerfully by humidity, and will therefore contain little or no uric acid. In the very elaborate examination of guano by T. Oellacher, apothecary at Inns- bruck, published in a recent number of Buchner's Repcrtorium of Pharmacy , it is said, that if a glass rod dipped into muriatic acid be held over guano, strong fumes are de- veloped; and the solution of guano has an alkaline reaction with litmus-paper. These phenomena evidently indicate the presence of carbonate of ammonia, and of course a partially decomposed guano ; for sound Chincha and Bolivian guanos have an acid re- action, proceeding from the predominance of phosphoric acid. Farmers frequently judge of the goodness of guano by the strength of the ammoniacal odor ; but in this judgment they may egregiously err, for the soundest guano has no smell of ammonia whatever ; and it begins to give out that smell only when it is more or less decomposed and wasted. Oellacher could find no evidence of urea in his guano ; I have obtained fully 5 per cent, of this substance from good Peruvian guano. I shall now describe my own system of analysis : — 1. In every case I determine, first of all, the specific gravity of the guano ; which I lake by means of spirits of turpentine, with a peculiar instrument contrived to render the process easy and precise. If it exceeds 1*75 in density, water being 1*0, it must contain sandy impurities, or has an excess of earthy phosphates, and a defect of azotized animal matter. 2. I triturate and digest 200 grains of it with distilled water, filter, dry the insoluble matter, and weigh it. 3. The above solution, diffused in 2,000 gr. measures, is examined as to its specific gravity, and then with test paper, to see whether it be acid or alkaline. 4. One naif of this solution is distilled along with slaked_ lime in a matrass connected with a small quintuple globe condenser, containing distilled water, and immersed in a basin of the same. As the condensing apparatus terminates in a water-trap, no part of the ammonia can be lost ; and it is all afterward estimated by a peculiar meter, whose indicatioi.s make manifest one hundredth part of a grain. 5. The other half of the solution is mixed with some nitric acid, and divided into 3 equal portions. a, the first portion, is treated with nitrate of barytes, and the resulting sulphate ol barytes is collected, ignited, and weighed. 6. the second portion, is treated with nitrate of silver, and the resulting chloride of silver ignited and weighed. c, the third portion, has a certain measure of a definite solution of ferric nitrate mixed with it, and then ammonia in excess. From the weight of the precipitated subphosphate of iron after ignition, the known amount of oxide used being deducted, the quantity of phosphoric acid in the soluble portion of the guano becomes known. /i, the three above portions are now mixed, freed by a few drops of dilute sulphuric and hydrochloric acids from any barytes and silver left in them, and then tested by nitrate of lime for oxalate of ammonia. The quantity of oxalate of lime obtained, de- termines that point. 6. The last liquor filtered, being freed from any residuary particles of lime by oxalate of ammonia, is evaporated to dryness and ignited, to obtain the fixed alkaline matter. This being weighed, is then dissolved in a little water, neutralized with acid, and treated with soda-chloride of platinum. From the quantity of potash-chloride of platinum, which precipitates, after being filtered, dried, and weighed, the amount of potash present is deducted — the rest is soda. These bases may be assigned to the sulphuric, hydro-chloric, and phosphoric acids, in proportions corresponding to their respective affinities. 7. The proportion of organic matter in the above solution of guano, is determined directly by evaporating a certain portion of it to dryness, and igniting. The loss of GUANO. 963 weight, minus the anmaonia and oxalic acid, represents the amount of organic matter. 8. A second portion of a solution of the guano is evaporated to dryness by a gertle steam heat, weighed, enclosed in a stout well-closed phial along with alcohol of 0*825, and heated to 212^. After cooling, the alcoholic solution is decanted or filtered clear, evaporated to dryness by a gentle h at, and weighed. This is urea, which may be tested by its conversion into carbonate of a imonia, when heated in a test tube or small retort. In this way, I have obtained from Bo. ivian guano, 5 per cent, of urea ; a certain proof of its entire soundness. 9. .Analysis of the insoluble matter. One third of it is digested with heat in abundance of Borax-water, containing ^i^. of the salt, filtered, and the filter dried by a steam heat. The loss of weight indicates the amount of uric acid, which is verified by supersaturating the filtrate with acetic or hydrochloric acid, thus precipitating the uric acid, throwing it upon a filter, drying, and weighing it. This weight should nearly agree with the above loss of weight, the small difference being due to soluble organic matter, sometimes called geine and ulmic acid. The uric acid is evidenced, 1, by its specific gravity, which 1 find to be only 1'25, as also that of the urate of ammonia ; 2, by its aflbrding fine purple murexide when heated in a capsule along with nitric acid, and then exposed to the vapor of ammonia from a feather held over it ; 3, by its dissipation when heated, without emitting an empyreumatic odor. 10. Another third of the solid matter is distilled along with half its weight of slaked lime, and 10 times its weight of water, in the apparatus already described, and the am- monia obtained from it estimated. 11. The remaining third having been ignited, is digested with a gentle heat in weak hydrochloric acid, and the undissolved silica and alumina washed on a filter, dried, and weighed. To the hydrochloric solution, dilute sulphuric acid is added, and the mixture is heated till all the h^'drochloric acid be expelled, with the greater part of the water. Alcohol of 0'850 is now poured upon the pasty residuum, and the whole, after being well stirred, is thrown upon a filter. The phosphoric acid passes through, as also the magnesia in union with sulphuric acid. The sulphate of lime, which is quite insoluble in spirits of wine, being washed with them, is dried, ignited, and weighed. From the weight of sulphate of lime, the quantity of phosphate of that earth, that was present, becomes known. 12. Ammonia in excess is now added to the filtrate, which throws down the granular phosphate of ammonia and magnesia. After washing and drying this powder at a heat of l.^'O'^, its weight denotes the quantity of that compound in the guano. 13. To the filtered liquor (of 12), if a little ammonia be added, and then muriate ol magnesia be slowly dropped in, phosphate of ammonia and magnesia will precipitate, from the amount of which the quantity of phosphoric acid may be estimated. 14. The pvoDortion of oxalate of lime is determined by igniting the washed residuuic (of 9) and placing it in an apparatus for estimating the quantity of carbonic acid given off in dissolving carbonate of lime. The apparatus, either fig. 1 or 2, described in my littie Treatise on Alkalimetry, will serve that purpose well. I have rarely obtained more than ^ gr. of carbonic acid from the insoluble residuum of 100 gr. of good guano, and that corresponds to less than 1| per cent, of oxalate of lime in the guano. Some- times no effervescence at all is to be perceived in treating the washed residuum with acid af^er ignition. 15. The carbonate of ammonia in guano is readily determined by filtering the solution of it in cold water, and neutralizing the ammonia with a test or alkalimelrical acid. (See the Treatise on Alkalimetry, above referred to.) 16. Besides the above series of operations, the following researches must be made to complete our knowledge of guano. The insoluble residuum (of 10) which has been deprived by two successive operations of its uric acid and ammonia, may contain azo- tized organic matter. It is to be therefore well dried, mixed with 5 times its weight of the usual mixture of hydrate of soda and quicklime, and subjected to gentle ignition in a glass or iron tube closed at one end, and connected at the other with an ammonia condensing apparatus. The amount of ammonia being estimated by a proper ammonia meter, represents the quantity of azote, allowing 14 of this element for 17 of ammonia, beina: the potential ammonia corresponding to the undefined animal matter. In a sample of Peruvian guano I obtained 5 per cent, of ammonia from this source. 17. The whole quantity of ammonia producible from guano is to be determined by gently igniting 25 gr. of it well dried, and mixed with ten times its weight of the mix- ture of hydrate of soda and quicklime (2 parts of the latter to 1 of the former;. The ammonia disengaged is condensed and measured, as described above. 18. The ready-formed ammonia is in all cases determined by distilling a mixture ot 100 gr. of it with 50 gr. of slaked lime, condensing the disengaged ammonia, and esti mating it exactly by the meter. 19. The relation of the combustible and volatile to the incombustible and fixed con- stituents of guano, is determined by igniting 100 gr. of it in a poised platinum capsule. 964 GUANO. The loss of weight denotes the amount of combustible and volatile matter, including the moisture, which is known from a previous experiment. 20. The insoluble matter is digested in hot water, thrown upon a filter, dried, and weighed. The loss of weight is due to the fixed alkaline salts, which, after concentra- ting their solutions, are investigated by appropriate tests : 1, nitrate of barytes for the sulphates; 2, nitrate of silver for the chlorides and sulphates; and 3, soda-chloride of platinum, for distinguishing the potash from the soda salts. 21. The insoluble matter (of 20) is digested with heat in dilute nitric or hydro- chloric acid, and the whole thrown upon a filter. The silica which remains on the filter is washed, ignited, and weighed. The lime, magnesia, and phosphoric acid, may be determined as already pointed out. 22. I have endeavored to ascertain if muriate of ammonia be present in guano, by evaporating its watery solution to dryness, and subliming the residuum, but I have never obtained a satisfactory portion of sal ammoniac; and therefore I am inclined to think there is little of it. The quantity of chlorine to be obtained from guano is too in- considerable to lead to a suspicion of its presence, except in combination with sodium and potassium. Phosphate of soda is also a doubtful product — but if present, it may be obtained from the saline matter (of 20), by acidulating it with nitric acid ; precipita- ting first with nitrate of barytes, next with nitrate of silver, taking care to use no ex- cess of these two re-agents, then supersaturating the residuum with ammonia, and ad- ding acetate of magnesia, when the characteristic double phosphate of this earth should fall, in case phosphate of soda be present. By the preceding train of researches, all the constituents of this complex product may be exactly disentangled and estimated ; but they manifestly require much care, patience, time, and dexterity^ and also a delicate balance, particularly in using the appropriate apparatus for generating the potential ammonia, and for measuring the whole of this volatile substance separated in the several steps of the process. It may be easily im- agined how little confidence can be reposed in many of the analyses of guano, framed, I fear, too often with the view of promoting the sale of an indiflferent or even spurious article of commerce. A. I shall now give in detail my analytical results upon three diflferent samples of a good South American guano ; and next the general results upon three samples of African and Chilian guanos : — 1. Guano from Bolivia, imported by the Mary and Anne. Thb sample was taken by myself, as an average out of several bags in the lighter, before the cargo was landed. Pale yellow brown color, dry, partly pulverulent, partly concreted, in small lumps, with a few small fragments of granite interspersed, and which, being obvious, were separated prior to the analysis. Specific gravity of the pulverulent portion without the granite, 1 60 ; of the concretions, 1-66; mean 1'63. Water digested on the formef portion is neutral to litmus, that on the latter is faintly acid. 2. 100 parts lose 6-5 by the heat of boiling water, and exhale no ammonia. When digested and triturated with cold water, 30'5 parts dissolve, and 69-5 are obtained after dr>'ing, at 212° F. Of those 30-5 parts, 6-5 are therefore water, easily separable, and 24-5 parts are solid matter. 3. 100 parts, mixed with 9 times their weight of water, and 50 of lime, being distilled in an alembic connected with the five-globe condenser, &c., afforded exactly 4-2 of am- monia. 20 grains in fine powder, along with 200 of a mLxture, consisting of 2 parts of dry lime and 1 of hydrate of soda, were gently ignited in a combustion-tube connected with the ammonia-condensing apparatus, and they produced 4-25 grains of ammonia-— equivalent to 21-25 from 100 grains of the guano. Thus only 4*2 per cent, of ammonia were ready formed; while 17*05 lurked, so to speak, in their azotized elements. From its aspect, and its want of ammoniacal odor, this guano, the first cargo re- ceived from Bolivia, was imagined by the importers to be of bad quality ; and, accord- ingly, my very favorable report of its analysis surprised them not a little, and rather unsettled the little faith they at that time (January, 1843) had in chemistry. But about a fortnight after the date of my report they received a letter from Peru, apprizing them of the excellence of that cargo of Bolivian guano, and of its being prized by the Ameri- cans, as possessing fertilizing powers in a pre-eminent degree. I consider this guano, therefore, as a type of the substance in its best state. II. The soluble matter was analyzed, in the manner already detailed, and was found to consist of — 1. Urea 2. Sulphate of potash - . - 3. Chloride of sodium - - . 4. Biphosphate of ammonia 5. Oxalate of anmionia - - - GUANO. 965 In these ammoniacal salts there are only 1-65 parts of ammonia; but I obtained 2-55 grains m distilling the soluble matter of 100 grains of the guano. The remaining 0-9 parts, therefore, must have proceeded from the partial decomposition of the urea during the long ebullition necessary to extract every particle of ammonia, in distilling the guano along with lime. HI. The ivsoluble matter =69*5 parts, was found to consist of— 1. 2. 3. 4. 5. Silica -----... 2'25 Subphosphate of lime - - - . . 9*00 Phosphate of magnesia and ammonia - - . i.25 Urate of ammonia - . _ . _ . 15*27 Undefined azotized organic matter, aflfording, with the 14 parts of uric acid, by ignition with hydrate of soda, 17-05 parts of ammonia --,--_ 41'73 69-50 This result as to the large proportion of organic matter in the dried insoluble residu- vm was verified by igniting a given quantity of it, when it was found to lose, out of 69-5 parts, 57 ; corresponding to the 15-27 urate of ammonia, 41-73 of undefined organic matter, and 0-08 of ammonia, in the double magnesian phosphate. In the urate and double phosphate are 1-35 of ammonia, which, with the 2-55, make 3-9 parts; the other 0-3 parts may be traced to the urea. As these results difl'er very considerably in many respects from those of the analyses Bttade by respectable German chemists, 1 was careful to verify them by manifold varia- tions of the process, as follows : — « 1. The soluble matter, with acid reaction, of 100 parts of the lumps of the Bolivian guano, was examined by per-acetate of iron and ammonia, for phosphoric acid, and afforded 4 parts of it, which is more than had been found in the neutral pulverulent guano. After the phosphoric acid was separated by that method, chloride of calcium gave no cloud with the filtered liquor, proving that no oxalic acid was present in these nodules. The washed insoluble matter, when gently ignited, and treated with dilute citric acid, aflTorded no effervescence whatever, and therefore showed that no oxalate of lime had been present, for it would have become a carbonate. It is necessary to determine from time to time the quantity of ferric oxide in tne acetate or nitrate, as it is liable to be deposited from the solution when this is kept for some time. If this point be not attended to, serious errors would be committed in the estimation of the phosphoric acid. 2. The quantity of uric acid was verified by several repetitions, and found to be 14 per cent. 3. The undefined organic matter, when deprived of the uric acid by prolonged diges- tion with weak borax, being subjected to ignition along with hydrate of soda, yielded the quantity of ammonia requisite to constitute the whole sum, that producible from the uric acid also being taken into account. 4. The little lumps of the guano afforded, by distillation along with quicklime 5-27 per cent, of ready-formed ammonia, probablv from the uric acid havin<' been partially decomposed by the moisture which had caused them to concrete. It is a curious fact that the solution of borax, from being of an alkaUne, becomes of an acid reaction, after digestion with the Bolivian guano. 5. For distinguishing and separating the soda salts from those of potash, I tried the antimoniate of potash, according to Wackenroder's prescription, but I found reason to prefer very much the crystallized soda-chloride of platinum, for that purpo«:e. From another specimen of the Bolivian guano, I extracted 3-5 per ct. of the ammonia- phosphate of magnesia. B. A sample of guano from the Chincha islands, of nearly the same light color as the preceding, and the same dryness, being an early importation of 250 tons in the present year, was subjected by me to a careful analysis. 1. The solution m water of this guano had an alkaline reaction from caibonate of amrnonia, which, being neutralized by test acid, indicated 0-34 per cent, of ammonia, eiuivalent to about 1 of the smelling sesqui-carbonate. 2. Of this guano, 47 per cent, were soluble in water^ and 53 per cent, remained, after drying at a heat of 212^ F. Of the above 47 parts, 8-5 were moisture in the guano. .i. The solution being acidulated with nitric acid, was treated with acetate of barytes, m a quantity equivalent to the sulphuric acid present, and it afforded 12 parts of sul- phate of barytes. With the filtered liquor, 700 water grain measures of ferric acetate were mixed, and then ammonia in excess ; 18-5 parts of washed and ignited sub-phosphate of iron were obtained, from which deducting 8-8 parts present in the acetate, 9-7 re- main as the quantity of phosphoric acid ; but 9-7 of acid produce 13-25 of bi-phos- phate of ammonia, which contain only 2-3 of ammonia, combined with 0-95 of water. 966 GUANO. or its elements. From the alkaline excess in the guano, there can be no doubt, how- ever, that it contained the sub-phosphate {faimd in the urine of Carnivora), and not the bi-phosphate of that base. In this case, 9-7 of acid produce 14-32 of dry saline com- pound, containing 4*62 of ammonia, which, with the 0-34 of ammonia in the carbonate, constitute a sum of 4'96. To the liquor freed from the phosphate of iron, and acidu- lated with nitric acid, acetate of lime being added, 3*33 parts of oxalate of this base were obtained, which are equivalent to 3*23 oxalate ammonia, containing 0*89 of am- monia. 4. Nitrate of silver now produced from the filtered residual solution 8 parts of chlo- ride, corresponding to nearly 3 of sal ammoniac, which contain nearly 0*95 of ammonia. 5. The 53 parts insoluble in water were digested with weak solution of borax at a boil- ing heat, thrown on a filter, and the uric acid being precipitated from the filtrate by means of a little hydrochloric acid, washed and dried, was found to weigh 13-5 parts. There were left on the filter 36*5 parts, dried at 212° F., so that 3 parts of soluble or- ganic matter had passed through the filter. These 36*5 parts lost by ignition only 9*7 parts in organic matter, became white, and afforded a very faint eflfervescence with hydro-chloric acid, showing that a very little oxalate of lime had been present. 1*23 parts of silica were left after the action of the acid. To the solution of the 26-55 parts, sulphuric acid was added, and the mixture being heated to expel the hydro-chloric acid and the excess of the sulphuric, the residuary matter was digested and washed with di- lute alcohol, and thrown on a filter ; the solution of magnesia passed through, while the sulphate of lime remained. After ignition, this weighed 27*5 parts, equivalent to 22 of sub-phosphate of lime. On supersaturating the filtrate with ammonia, 4*5 parts of the magnesian ammonia phosphate were precipitated, containing 0.32 of ammonia. With the 13»5 parts of uric acid, 1*23 of ammonia had be'en originally combined, forming 14*73 of urate. 6. 25 grains of the dry guano afforded, by ignition in the combustion-tube along with 200 grains of the mixed lime and hydrate of soda, 4*165 of ammonia, which correspond to 16*66 in 100 parts of the dry, or to 15*244 in the natural state; leaving therefore 5 parts for the quantity of potential ammonia, or of ammonia producible from the de composition of its azotized organic matter. This guano is, therefore, well adapted to promote permanently the fertility of a soil. It yields besides to alcohol a notable quantity of urea, which I did not think it worth while to determine quantitivelv, and from which undoubtedly a portion of the ammonia proceeded, in the distillation vitL milk of lime. 7. 100 parts afforded by distillation with milk of lime, 10*2 of ammonia. 8. The total constituents of that guano, being tabulated, are — 1. Matter soluble in water - - - 47*00 consisting of — 1. Sulphate of potash, with a little sulphate of soda 2. Muriate of ammonia ... 3. Phosphate of ammonia 4. Sesqui-carbonate of ammonia 5. Sulphate of ammonia - - - 6. Oxalate of ammonia - - - 7. Water . . . . . S. Soluble organic matter and urea II. Matter insoluble in water consisting of — 1. Silica . . . . 2. Undefined organic matter 3. Urate of ammonia - - - 4. Oxalate of lime - _ . 5. Sub-phosphate of lime 6. Phosphate of magnesia and ammonia The remaining 1.25 of actual ammonia may be fairly traced to the partial decomposi tion of the urea during the distillation with lime ; whereas the 5 per cent, of potential ammonia proceeded from the transforming decomposition of the uric acid. C. Foliated guanOy from Peru, in caked pieces, the layers very thin, parallel, and in- terspersed with white streaks. This guano was somewhat dense for a pure specimen, having a specific gravity of 1*7. The insoluble matter afforded by digestion with borax — — Ammonia 6*00 3*00 0.95 14-32 4*62 1-00 0*34 2*00 0-50 3*23 0*89 8*50 8*95 47-00 53*00 1-25 9*52 14*73 1-23 1*00? 22*00 4*50 0*32 53*00 9*80 GUANO. 967 water, no less than 25*2 perct. of pale yellow uric acid; 9 of other combustible organic matter, and 15 of earthy matter; consisting of silica, 3*5; phosphate of magnesia and ammonia, 6-5 ; and only 5 of sub-phosphate of lime or bone earth. It lost 10 per cent, when dried in a heat of 212° F. The remaining 30*8 parts soluble in water, had a strong acid reaction, and afforded, by ferric acetate and ammonia, 6 of phosphoric acid, equivalent to 9*7 of crystallized bi-phosphale of ammonia, after acetate of barytes had separated the sulphuric acid. No less than 17 parts of chloride of silver were obtained, by precipitating with nitrate of silver the liquor filtered from the phosphate of iron, and acidulated with nitric acid. As the present is an accidental sample, and not an average of any importation, I did not prosecute the research further. I). Chincha guano, of a somewhat darker color than the preceding, and alkaline re- action ; specific gravitj', 1*62. Digested with water and strained, 56*75 parts remained after drying it at 212° F. The solution, evaporated and dried also at 212°, afforded 31*25 of saline matter. This saline mass being mixed with four fifths of its weight of slaked lime, nine times its weight of water, and distilled, aflforded of ammonia 14*28 per cent. Some chemists have prescribed potash instead of lime, for separating the am- monia in distillation ; but no person of intelligence who has made the experiment once will choose to repeat it, because the potash forms with the organic matter of the guano a viscid compound, that froths up like a mass of soap-bubbles, and coming over with the vapors, obstructs and vitiates the result. 2. When dried altogether by a steam heat, 100 parts lost 12 in moisture ; whereas by evaporating and drying the soluble matter by itself, the loss amounted to 16*3, no doubt by the dissipation of some of the ammoniacal salts ; for 100 parts of the entire guano aflbrd, by distillation with quicklime, 9 parts of ammonia, and bv the trans- forming decomposition with hydrate of soda and lime, 16*25, indicating 7*25 of potential ammonia, in addition to the 9 of ready formed. The insoluble matter of 100 parts afforded to borax-water a solution containing 16*5 of uric acid, corresponding to 18 of urate of ammonia. There remained on the filter, after dr^'ing it at 212° F., only 33*8 parts; so that about 5 parts of soluble organic matter had passed through the filter io the borax water. These 33*8 consisted of subphosphate of lime 17, magnes;an phos- phate of ammonia 5*5, silica 0*7, and combustible organic matter 10*6. The ammonia in the soluble portion was in the state chiefly of phosphate; there was merely a faint trace of oxalate of ammonia. E. African Guam).— Among the many samples of African guano which I have had occasion to analyze for the importers, none has contained any appreciable quantity of uric acid, or by consequence of potential ammonia. The best aflforded me 10 per cent, of ready-formed ammonia, existing chiefly in the state of a phosphate, though they all contain carbonate of ammonia, and have of consequence an alkaline reaction. The said sample contained 21*5 of moisture, separable by a heat of 212° F. Its specific gravity was so low as 1*57, in consequence of the large proportion of moisture in it. It contained 23 per cent, of subphosphate of lime, 3 of magnesian phosphate of am- monia, 1 of silica, and 1*5 of alkaline sulphate and muriate. The remaining 50 parts consisted of decayed organic matter, with phosphate of ammonia, and a little carbonate, equivalent to half a grain of ammonia, which is the largest quantity in such guanos. Other African guanos have aflx)rded from 24 to 36 of moisture, no uric acid ; no po^ tential ammonia; but decayed organic matter; from 5 to 7 of ready-formed ammonia in the state of phosphate, with a little carbonate; from 25 to 35 per cent, of subphosphate of lime ; 5 or 6 of the magnesian phosphate of ammonia ; more or less oxalates from the decomposition of the uric acid, and 3 to 5 per cent, of fixed alkaline salts. F. The Chilian Guam gathered on the coasi, already adverted to, contained a remarka- ble proportion of common salt, derived probably from the sea spray. The following is the general report of the chemical examination of several samples of guano, which I made for Messrs. Gibbs of London, and Messrs. Myers of Liverpool : — " In these various analyses, performed with the greatest care, and with the aid of the most complete apparatus for both inorganic and organic analysis, my attention has been directed, not only to the constituents of the guano which act as an immediate manure, but to those which are admitted by practical farmers to impart durable fertility to the grounds. The admirable researches of Professor Liebig have demonstrated that Azote, the indispensable element of the nourishment of plants, and especially of wheat and others abounding in gluten (an azotized product), must be presented to them in the state of ammonia, yet not altogether ammonia in the pure or saline form, for, as such, it is too readdy evaporated or washed away ; but in the dormant, or as one may say, in the potential condition in contradistinction from the actual. Genuine Peruvian and Bolivian guanos, like those which I have minutely analyzed, surpass very far all other species of manure, whether natural or artificial, in the quantity of potential ammonia, and, therefore, m the permanency of their action upon the roots of plants, while, in conse quence of the ample store of actual ammonia which they contain ready formed, they 968 GUANO. GUMS. i s 3 3 ore qualified to give immediate visror to vearetation. Urate of airmonia constitutes a considerable portion of the azotized organic matter in well-pr( served guano; it is nearly insoluble in water, not at all volatile, and is capable of yielding to the soil, by its slow decomposition, nearly one third of its weight of ammonia. No other manure can rival this animal saline compound. One of the said samples cf guano afforded me no less than 17 per cent, of potential ammonia, besides 4^ per cent, of the actual or ready formed ; others from 7 to 8 per cent, of ammonia in each of these states re- spectively. These guanos which I have examined are the mere excrement of birds, and are quite free from the sand, earth, clay, and common salt, reported in the analyses of some guanos, and one of which (sand) to the amount of 30 per cent. I found myself n a sample of guano from Chile. " The Peruvian guano, moreover, contains from 10 to 25 per cent, of phosphate of lime, the same substance as bone-earth, but elaborated by the birds into a pulpy con- sistence, which, while it continues insoluble in water, has been thereby rendered more readily^ absorbable and digestible (so to speak) by the roots of ilants. I have there- fore no doubt, that by the judicious application of these genuine guanos, mixed with twice or thrice their weight of a marly or calcareous soil, to convert their phosphate of ammonia into phosphate of lime and carbonate of ammonia, as also to dilute all their ainmoniacal compounds — such crops will be produced, even un sterile lands, as the farmer has never raised upon the most improved soil by the best crdinary manure. To the West India planter, guano will prove the greatest boon, sir ce it condenses in a portable and inoffensive shape the means of restoring fertility to his exhausted cane- fields, a benefit it has long conferred on the poorest districts of Peru. ** I respectfully observe, that no analysis of guano hitherto u ade public at all ex- habits the value of tne cargoes referred to above, while none gives the quantity of ammonia dormant in the azotized animal matter of the birds' dung, which, called into activity with the seeds in the soil, becomes the most valuable of its constituents, as a source of perennial fertility. In the detailed account of my anrlyses of this complex excretion (now preparing for publication), all the above statements will be bioughl within the scope of general comprehension. I shall also describe my ' ammonia gene- rator,' based on the process invented in the laboratory of Professor Lii**big, and also my * ammonia metei ,' which, together, can detect and measure one hundredth part of a grain weight of absolute ammonia, whether potential or actual, in any sample of guano. " Meanwhile the following may be oflered as the average result of my analyses of genuine guano in reference to its agricultural value : — *' 1. Azotized animal matter, including urate of ammonia, to- gether capable of afiording from 8 to 16 per cent, of ammonia by slow decomposition in the soil - - 50 2. Water 8 to 11 3. Phosphate of lime - - - - - 12 to 25 4. Phosphate of ammonia, sulphate of ammonia, ammonia- phosphate of magnesia, together containing from 6 to 9 parts of ammonia - - - • - 13 5. Siliceous sand - - - - • - 1 100 " Very moist guano has in general more actual and less potential ammonia than the d:y guano. "Andrew Ure. ** Londony 13 Charlotte street, Bedford square, " February 14, 1843." Oellacher's analysis of a brownish yellow guano is as follows [see top of next page] :— I am satisfied from its large proportion of oxalate of ammonia, that the sample Xhr% analyzea was by no means a fair or normal specimen of guano ; and it is in fact widely different from all the fresh samples which have passed through my hands. It is described as " knobby, being mixed with light laminated crystalline portions, in white grains, from the size of a pea to that of a pigeon's e^^." Having some lumpy concre tions of a similar aspect in my possession, I submitted them to chemical examination. G. 1,000 grains being digested in boiling water and strained, afforded a nearly color- less solution. This was concentrated till crystals of oxalate of ammonia appeared. It was then acidulated with hydrochloric acid, to protect the phosphoric acid from pre- cipitation, and next treated carefully with a solution of nitrate of lime equivalent to the oxalic acid present. The oxalate of lime thus obtained being converted into carbonate weighed 80-5 grains, corresponding to 100 of oxalate of ammonia, being 10 per cent, of the weight of the guano. 1. Urate of ammonia 2. Oxalate of ammonia 3. Oxalate of lime - - - 4. Phosphate of ammonia 5. Phosphate of ammonia and magnesia 6. Phosphate of lime - - - 7. Muriate of ammonia 8. Chloride of sodium (common salt) - 9. Carbonate of ammonia 10. Carbonate of lime 11. Sulphate of potash 12. Sulphate of soda 13. Humate of ammonia 14. Substance resembling wax - 15. Sand . _ . - 16. Water (hygroscopic) 17. Undefined organic matter - Ammonia. . 12-20 1-06 - 17-73 6-50 - 1-30 - 6-90 1-79 - 11-63 1-68 - 20-16 - 2-25 0-72 - 0-40 - 0-80 0-23 - 1-65 - 4-00 - 4-92 - 1-06 009 . 0-75 ■ 1-68 . 4-31 8-26 100-00 12-07 The liquor filtered from the oxalate was precipitated by nitrate of barytes, and afforded 112 grains of sulphate of barytes = 38 sulphuric acid; and the last filtrate being mixed with a given measure of ferric acetate, and the mixture supersaturated with ammonia, yielded subphosphate of iron, equivalent to 5 per cent of phosphoric acid. I digested with heat other 500 grains of the same guano in a weak solution of borax, filtered, acidulated the liquid, but obtained merely a trace of uric acid. It i* clear thereft-TC that the oxalate of ammonia had been formed in this guano at the expense of the uric acid, and that its concreted state, and the crystalline nodules dis- seminated through it, were the result of transformation by moisture in a hot climate, which had agglomerated it to a density of 1-73 ; whereas clean fresh guano, friable and dry like the above, is seldom denser than 1-65. The guano contained only 3-23 of ar-jmonia ; 65 of insoluble matter, 53 of earthy phosphates, 5 silica, 3 alkaline salts (.fixed), and 7 organic matter. Oxalate of ammonia, being readily washed away, it is a bad substitute for the urate of ammonia, urea, and azotized animal matter, which it has replaced. Oellacher eouid find no urea in the guano which he analyzed ; another proof of its dis- integration. Rartel's analysis of a brown-red guano is as follows : — 1. Muriate of ammonia - - - - - - 6-500 2. Oxalate of ammonia - - ... - 13-351 3. Urate of ammonia -------- 3*244 4. Phosphate of ammonia ------- 6-450 5. Substances resembling wax and resin - - - - ^-600 6. Sulphate of potash _.----- 4-277 7. Sulphate of soda - - - - - - - -1*119 8. Phosphate of soda 5*291 9. Phosphate of lime 9-940 10. Phosphate of ammonia and magnesia - _ - 4-196 11. Common salt --.---.. 0-100 12. Oxalate of lime 16-360 13. Alumina --------- 0*104 14. Sand insoluble in nitric acid, and iron - - . - 5-800 15. Loss (water and volatile ammonia and undefined organic matter) 22*718 100-000 Voelckel, in his analysis of guano, states 7 per cent, of oxalate of lime— a result quite at variance with all my experience — for I have never found so much as 2 per cent, of carbonate of lime in the washed and gently ignited insoluble mutter ; whereas, accoi-ding to Bartels and Voelckel, from 10 to 5 per cent, of carbonate should be obtained, as the equivalents of the proportions of the oxalate assigned by them. All these analyses are defective moreover in not showing the total quantity of ammonia which the guano is capable of giving out in the soil ; and since it appears that the freshest guano abounds most in what I have called potential ammonia, it must Dossess of con- sequence, the greatest fertilizing virtue. f 970 GUM RENINS. GUNPOWDER. 971 4 sent A sample of decayed darh-hro^m moist guano from Chile, being examined an above described, for oxalate of ammonia, was found to contain none whatever ; and it contained less than 1 per cent, of uric acid. H. An article offered to the public, by advertisement, as Peruvian guano, was lately nt to me for analysis. I found it to bo a spurious composition ; it consisted of — 1. Common salt - - . . - 2. Common siliceous sand .... Sulphate of iron or copperas Phosphate of lime .... Organic matter from bad guano, «fcc (to give it smell) Moisture - . . . 3. 4. 6. 6. 320 280 5-2 40, with 23-3 7-6 1000 Genuine guano, wlien burned upon a red hot shovel, leaves a white ash of phos' phate of lime and magnesia ; whereas this factitious substance left a black fused mass of sea salt, copperas, and sand. Tlie specific gravity of good fresh guano is seldom more than 1-66, water being 100; whereas that of the said substance was so high as 2-17, produced by the salt, sand, and copperas. GUM {Gomme, Fr. ; Gummi, Pflamenschhim, Germ.) is the name of a proximate vegetable product, which forms with water a slimy solution, but is insoluble in alcohol, ether, and oils ; it is converted by strong sulphuric acid into oxalic and mucic acids. There are six varieties of gum : 1. gum arabic ; 2. gum Senegal ; 3 gum of the cherry and other stone fruit trees : 4. gum tragacanth; 5. gum of Bassora ; 6. the gum of seeds and roots. The first five spontaneously flow from the branches and trunks of their trees, and sometimes from the fruits, in the form of a mucilage which dries and hardens in the air. The sixth kind is extracted by boiling water. Gum arabic and gum Senegal consist almost wholly of the purest gum ^.alled arabine by the French chemists; our native fruit trees contain some c«rasj«e, along with ars bine ; the gum of Bassora and gum tragacanth consist of arabine and bassorine. Chim arabic flows from the acacia arabica, and the acacia veruj which grow upon the banks of the Nile and in Arabia. It occurs in commerce in the form of small pieces, rounded upon one side and hollow upon the other. It is transparent, without smell, brittle, easy to pulverize, sometimes colorless, sometimes with a yelk -/ or brownish tint. It may be bleached by exposure to the air and the sun-beams, at the temperature of boiling water. Its specific gravity is 1-355. Moistened gum arabic reddens litmus paper, owing to the presence of a little supermalate of lime, which may be removed by boiling alcohol ; it shows also traces of the chlorides of potassium and calcium, and the acetate of potash. 100 parts of good gum contain 70*40 of arabine, 17-60 of water, with a few per cents, of saline and earthy matters. Gum arabic is used in medicine, as also to give lustre to crapes and other silk stuifs. Gum Senegal is collected by the negroes during the month of November, from the acacia Senegal, a tree 18 or 20 feet high. It comes to us in pieces about the size of a partridge egg, but sometimes larger, with a hollow centre. Its specific gravity is 1*436. It consists of 81*10 arabine; 16*10 water; and from 2 to 3 of saline matters. The chemical properties and uses of this gum are the same as those of gum arabic. It is much employed in calico-printing. Cherry-tree gum consists of 52*10 arabine; 54*90 cerasine ; 12 water; and 1 saline matter. Gum tragacanth is gathered about the end of June, from the astragalus tragacaniha of Crete and the surrounding islands. It has the appearance of twisted ribands ; is while or reddish ; nearly opaque, and a little ductile. It is difllicult to pulverize, without heat- ing the mortar. Its specific gravity is 1*384. When plunged in water, it dissolves m part, swells considerably, and forms a very thick mucilage. 100 parts of it consist of 53*30 arabine; 3330 bassorine and starch; 110 water; and from 2 to 3 parts of saline matters. It is employed in calico printing, and by shoemakers. Gum of Bassora ; see Bassorine. Gum of seeds, as linseed, consists of 52*70 arabine ; 28*9 of an insoluble matter ; 10-3 water; and 7*11 saline matter. Neither bassorine nor cerasine seems to be present in seeds and roots. For British Gum, see Starch. GUM RESINS. {Gomme-resines, Fr.; Schleimharzey Germ.) When incisions are made in the stems, branches, and roots of certain plants, a milky juice exudes, which gradually hardens in the air ; and appears to be formed of resin and essential oil, held suspended in water charged with gum, and sometimes with other vegetable matters, such as caoutchouc, bassorine, starch, wax, and several saline matters. Tie said con- crete juice is called a gum-resin ; an improper name, as it gives a false idea of the nature of the substance. They are all solid ; heavier than water ; in general opaque and brittle ; many have an acrid taste, and a strong smell ; their colour is very variable. They are partiallv soluble in water, and also in alcohol ; and the solution in the former liquid seldom becomes transparent. Almost all the gum resins are medicinal substances, and little employed in the arts and majiufactures. The following is a list of them : assa- fcetida ; gum anunoniac ; bdellium ; euphorbium ; galbanum ; gamboge ; myrrh ; oliba- num or frankincense ; opoponax ; and scammony. Some of these are described in this work under their peculiar names. GUMS. Under the generic name Gum several substances have been classed, which differ essentially, though they possess the following properties in common ; viz. form- ing a thick mucilaginous liquid with water, and being precipitable from that solution by alcohol. Properly speaking, we should style gums only such substances as are trans- formed into mucic acid by nitric acid; of which bodies there are three: I. Arabine, which constitutes almost the whole of gum arabic ; 2. Bassorine, which forms the chief part of gum tragacanth ; and 3. Cerasine, which occurs in cheny-tree gum, and ia con- vertible into gum arabic by hot water, 1. Gum arabic, in its ordinary state, contains 17 per cent, of water, separable from it by a heat of 212° Fahr. 2. Chorry-tree gum consists of 52 per cent of arabine, and 35 of a peculiar gum, which has been called Cerasine. Tliis latter substance is convertible into grape sugar oy boiling it with very dilute sulphuric acid. GUNPOWDER. The following memoir upon this subject was published by me in the Journal of the Royal Institution for October, 1830. It contains the results of several careful analytical experiments, as also of observations made at the Roval Gunpowder Works at Wallham Abbey, and at some similar establishments in the neighbourhood of London. Gunpowder is a mechanical combination of nitre, sulphur, and charcoal ; deriving the intensity of its explosiveness from the purity of its constituents, the proportion in which they are mixed, and the intimacy of the admixture. 1. On the nitre, — Nitre may be readily purified, by solution in water and crystalliza- tion, from the muddy particles and foreign salts with which it is usually contammated. In a saturated aqueous solution of nitre, boiling hot, the temperature is 240° F. ; and the relation of the salt to its solvent is in weight as three to one, by my experiments : not five to one, as MM. Bottee and Riffault have stated. We must not, however, adopt the general language of chemists, and say that three parts of nitre are soluble in one of boil- ing water, since the liquid has a much higher heat and greater solvent power than this expression implies. Water at 60*» dissolves only one fourth of its weight of nitre; or, more exactly, this saturated solution contains 21 per cent, of salt. Its specific gravity is 1*1415; 100 parte in volume of the two constituents occupy now 97*91 parts. From these data we may perceive that little advantage could be gained in refining crude nitre, by making a boiling- hot saturated solution of it; since on cooling, the whole would concrete into a moist saline mass, consisting by weight of 2f parts of salt, mixed with 1 part of water, holding \ of salt in solution, and in bulk of 1| of salt, with about 1 of li(juid ; for the specific gravity of nitre is 2*005, or very nearly the double of water. It is better, therefore, to use equal weights of saltpetre and water in making the boiling-hot solution. When the filtered liquid is allowed to cool slowly, somewhat less than thii^e fourths of the nitre will separate in regular crystals ; while the foreign salts that were present will remain with fully one fourth of nitre in the mother liquor. On redissolving these crystals with heat, in about two thirds of their weight of water, a solution will result, from which crystalline nitre, fit for every purpose, will concrete on cooling. As the principal saline impurity of saltpetre is muriate of soda (a substance scarcely more soluble in hot than in cold water), a ready mode thence arises of separating that salt from the nitre in mother waters that contain them in nearly equal proportion. Place an iron ladle or basin, perforated with small holes, on the bottom of the bailer in which the solution is concentrating. The muriate, as it separates by the evaporation of the water, will fall down and fill the basin, and may be removed from time to time. When small needles of nitre begin to appear, the solution must be run ofl" into the crys- tallizing cooler, in which moderately pure nitre will be obtained, to be refined by another similar operation. At the Waltham Abbey gunpowder works the nitre is rendered so pure by successive solutions and crystallizations, that it causes no opalescence in a solution of nitrate of silver. Such crystals are dried, fused in an iron pot at a temperature of from 500° to 600** F., and cast into moulds. The cakes are preserved in casks. About the period of 1794 and 1795, under the pressure of the first wars of their revolution, the French chemists employed by the government contrived an expeditious, economical, and sufficiently effective mode of purifying their nitre. It must be observed that this salt, as brought to the gun powder- works in France, is in general a much cruder 972 GUNPOWDER. GUNPOWDER. 973 11 Ji article than that imported into this country from India. It is extracted from the nttrous salts contained in the mortar-rubbish of old buildings, especially those of the lowest and filthiest descriptions. By their former methods, the French could not refine their nitre in less lime than eight or ten days; and the salt was obtained in great lumps, very difficult to dry and divide ; whereas the new process was so easy and so quick, that in less than twenty-four hours, at one period of pressure, the crude saltpetre was con- verted into a pure salt, brought to perfect dryness, and in such a state of extreme division as to supersede the operations of grinding and sifting, whence also considerable waste was avoided. The following is a brief outline of this method, with certain improvements, as now practised in the establishment of the Administration des poudres et saltpetres^ in France. The refining boiler is charged over night with 600 kiloarammes of water, afld 120C kilosrammes of saltpetre, as delivered by the salpetriers. No more fire is applied than is adequate to effect the solution of this first charge of saltpetre. It may here be observed, that such an article contains several deliquescent salts, and is much more soluble than pupa nitre. On the morrow morning the fire is increased, and the boiler is charged at different intervals with fresh doses of saltpetre, till the whole amounts to 3000 kilo- grammes. During these additions, care is taken to stir the liquid very diligently, and to skim off the froth as it rises. When it has been for some time in ebullilion, and when it may be presumed that the solution of the nitrous salts is effected, the muriate of soda is scooped out from the bottom of the boiler, and certain affusions or inspersions of cold water are made into the pot, to quicken the precipitation of that portion which the boiling motion may have kept afloat. When no more is found to fall, one kilogramme of Flanders plue, dissolved in a sufficient quantity of hot water, is poured into the boiler; the mix- lure is thoroughly worked together, the froth being skimmed ofi", with several successive inspersions of cold water, till 400 additional kilogrammes have been introduced, const!- tutmg altogether 1000 kilogrammes. When the refining liquor affords no more froth, and is grown perfectly clear, all manip. ulation must cease. The fire is withdrawn, with the exception of a mere kindhng, so as to maintain the temperature till the next morning at about 88° C. = 190-4 F. This liquor is now transferred by hand-basins into the crystallizing reservoirs, taking care to disturb the solution as little as possible, and to leave untouched the impure matter at the bottom. The contents of the long crystallizing cisterns are stirred back- wards and forwards with wooden paddles, in order to quicken the cooling, and the consequent precipitation of the nitre in minute crystals. These are raked, as soon as they fall, to the upper end of the doubly-inclined bottom of the crystallizer, and thence re- moved to the washing chests or boxes. By the incessant agitation of the liquor, no large crystals of nitre can possibly form. When the tem.porature has fallen to within 7° or 8* F., of the apartment, that is, after seven or eight hours, all the saltpetre that it can yield will have been obtained. By means of the double inward slope given to the crystallizer, the supernatant liquid is collected in the middle of the breadth, and may be easily laded The saltpetre is shovelled out of the crystallizer into the washing chests, and heaped up in them so as to stand about six or seven inches above their upper edges, in order to allow for the subsidence which it must experience in the washing process. Each of these chests being thus filled, and their bottom holes being closed with plugs, the salt is be- sprinkled from the rose of a watering-can, with successive quantities of water saturated with saltpetre, and also with pure water, till the liquor, when allowed to run off, indicates by the hydrometer, a saturated solution. The water of each sprinkling ought to remain on the salt for two or three hours; and then it may be suffered to drain off through the plug-holes below, for about an hour. AH the liquor of drainage from the first watering, as well as a portion of the second, is set aside, as being considerably loaded with the foreign salts of the nitre, in order to be evaporated in the sequel with the mother waters. The last portions are preserved, because they contain almost nothing but nitre, and may therefore serve to wash another dose of that salt. It has been proved by experience, that the quantity of water employed in washing need never exceed thirty-six sprinklings in the whole, composed of three waterings, of which the first two consist of fifteen, and the last of six pots = 3 gallons E.; or in other words, of fifteen sprinklings of water saturated with saltpetre, and twenty- one of pure water. . The saltpetre, after remaining five or six days in the washing chests, is transported into the drying reservoirs, heated by the flue of the nearest boiler; here it is stirred up from time to time with wooden shovels, to prevent its adhering to the bottom, or running into lumps, as well as to quicken the drying process. In the course of about four hours, it gets completely dry, in which state it no longer sticks to the shovel, but falls down into a soft powder by pressure in the handj and is perfectly white and pulverulent. It is now passed through a brass sieve, to separate any small lamps or foreign particles accidentally present, and is then packed up in bags or barrels. Even in the shortest winter days, the drying basin may be twice charged, so as to dry 700 or 800 kilogrammes. By this ope- ration, the nett produce of 3000 kilogrammes (3 tons) thus refined, amounts to from 1750 to 1800 kilogrammes of very pure nitre, quite ready for the manufacture of gun- powder. The mother waters are next concentrated ; but into their management it is needless to enter in this memoir. On reviewing the above process as practised at present, it is obvious that, to meet the revolutionary crisis, its conductors must have shortened it greatly, and have been content with a brief period of drainage. 2. On the sulphur. — The sulphur now imported into this country, from the volcanic districts of Sicily and Italy, for our manufactories of sulphuric acid, is much purer than the sulphur obtained by artificial heat from any varieties of pyrites, and may, therefore, by simple processes, be rendered a fit constituent of the best gunpowder. As it is not my purpose here to repeat what may be found in common chemical compilations, I shall say nothing of the sublimation of sulphur ; a process, moreover, much too wasteful for the gunpowder-maker. Sulphur may be most easily analyzed, even by the manufacturer himself ; for I find it to be soluble in one tenth of its weight of boiling oil of turpentine, at 316° Fahrenheit, forming a solution which remains clear at 180**. As it cools to the atmospheric tempera- ture, beautiful crystalline needles form, which may be washed sufficiently with cold alco- hol, or even tepid water. The usual impurities of the sulphur, which are carbonate and sulphate of zinc, oxyde and sulphuret of iron, sulphuret of arsenic and silica, will remain unaffected by the volatile oil, and may be separately eliminated by the curious, though •uch separaticn is of little practical importance. Two modes of refining sulphur for the gunpowder works have been employed ; the first is by fusion, the second by distillation. Since the combustible solid becomes as limpid as water, at the temperature of about 230° Fahrenheit, a ready mode offers of removing at once its denser and lighter impurities, by subsidence and skimming. But I may take the liberty of observing, that the French melting pot, as described in the elaborate work of MM. Bottee and Ritfault, is singularly ill-contrived, for the fire is kindled right under it, and plays on its bottom. Now a pot for subsidence ought to be cold set ; that is, should have its bottom part imbedded in clay or mortar for four or six inches up the side, and be exposed to the circulating flame of the fire only round its middle zone. This arrangement is adopted in many of our great chemical works, and is found to be very advantageous. With such a boiler, judiciously heated, I believe that crude sulphur might be made remarkably pure; whereas by directing the beat against the bottom of the vessel, the crudities are tossed up, and incorporated with the mass. See Evaporation. The sulphur of commerce occurs in three prevailing colors; lemon yellow verging on green, dark yellow, and brown yellow. As these different shades result from the differ- ent degrees of heat to which it has been exposed in its original extraction on the great scale, we may thereby judge to what point it may still be heated anew in the refinery melting. Whatever be the actual shade of the crude article, the art of the refiner con- sists in regulating the heat, so that after the operation it may possess a brixiant yellow hue, inclining somewhat to green. In seeking to accomplish this purpose, the sulphur should first be sorted according to its shades ; and if a greenish variety is to be purified, since this kind has been but little heated in its extraction, the fusion may be urged pretty smartly, or the fire may be kept up till everything is melted but the uppermost layer. Sulphur of a strong yellow tinge cannot bear so great a heat, and therefore the fire must be withdrawn whenever three fourths of the whole mass have been melted. Brown-colored brimstone, having been already somewhat scorched, should be heated as little as possible, and the fire may be removed as soon as one half of the mass is fused. Instead of melting, separately, sulphurs of different shades, we shall obtain a better re- sult by first filling up the pot to half its capacity, with the greenish-colored article, putting over this layer one quarter volume of the deep yellow, and filling it to the brim with the brown-colored. The fire must be extinguished as soon as the yellow is fused. The pot must then be closely covered for some time ; after which the lighter impurities will be found on the surface in a black froth, which is skimmed off, and the heavier ones sink to the br'tom. The sulphur itself must be left in the pot for ten or twelve hours, after which it is laded out into the crystallizing boxes or casks. Distillation affords a more complete and very economical means of purifying sulphur, which was first introduced into the French gunpowder establishments, when their importation of the best Italian and Sicilian sulphur was obstructed by the British navy. Here the sulphur need not come over slowly in a rare va^r, and be deposited 974 GUNPOWDER. in a pulverulent form called flowers ; for the only object of the refiner is to bring over the whole of the pure sulphur into his condensing chamber, and to leave all its crudities in the body of the stiJl. Hence a strong fire is applied to elevate a denser mass of vapors, of a yellowish color, which passing over into the condenser, are deposited in a liquid state on its bottom, whilst only a few lighter particles attach themselves to the upper and lateral surfaces. The refiner must therefore give to the heat in this opera- tion very considerable intensity ; and, at some height above the edge of the boiler, he should provide an inclined plane, which may let the first ebullition of the sulphur over- flow into a safety recipient. The condensing chamber should be hot enough to main- tain the distilled sulphur in a fluid state— an object most readily procured by leading the pipes of several distilling pots into it ; while the continuity of the operations is se- cured, by chaining each of the stills alternately, or in succession. The heat of the re- ceiver must be never so high as to bring the sulphur to a sirupy consistence, whereby its color is darkened. In the sublimation of sulphur, a pot containing about 4 cwts. can be worked off only once in twenty-four hours, from the requisite moderation of its temperature, and the pre- raution of an inclined plane, which restores to it the accidental ebullitions. But, by dis- tillation, a pot containing fully ten cwts. may complete one process in nine hours at most, with a very considerable saving of fuel. In the former plan of procedure, an interval must elapse between the successive charges ; but in the latter, the operation must be continuous to prevent the apparatus from getting cooled ; in sublimation, moreover, where communication of atmospheric air to the condensing chamber is indispensable, explosive combustions of the sulphurous vapors frequently occur, with a copious production of sul- phurous acid, and correspondent waste of the sulphur j disadvantages from which the dis- tillatory process is in a great measure exempt. I shall here describe briefly the form and dimensions of the distilling apparatus employed at Marseilles in purifying sulphur for the national gunpowder works, which was found adequate to supply the wants of Napoleon's great empire. This apparatus consists of only two still-pots of cast iron, formed like the large end of an egg, each about three feet in diameter, two feet deep, and nearly half an inch thick at the bottom, but much thinner above, with a horizontal ledge four inches broad. A pot of good cast iron is capable of distilling 1000 tons of sulphur before it is rendered unseryiceable, by the actiun of the brimstone on its substance, aided by a strong red heat. The pot is covered in with a sloping roof of masonry, the upper end of which abuts on the brickwork of the vaulted dome of condensation. A large door is formed in the masonry in front of the mouth of the pot, through which it is charged and cleared out ; and between the roof-space over the pot, and the cavity of the vault, a large passage is opened. At the back of the pot a stone step is raised to prevent the sulphur boiling over into the con- denser. The vault is about ten feet wide within, and fourteen feet from the bottom up to the middle of the dome, which is perforated, and carries a chimney about twelve feet high, and twelve feet diameter inside. As the dome is exposed to the expansive force of a strong heat, and to a very con- siderable pressure of gases and vapors, it must possess great solidity, and be theiefore bound with iron straps. Between the still and the contiguous wall of the condensing chamber, a space must be left for the circulation of air ; a precaution found by experience indispensable; for the contact of the furnaces would produce on the wall of the chamber such a heat as to make it crack and form crevices for the liquid sulphur to escape. The sides of the chamber are constructed of solid masonry, forty inches thick, sur- mounted by a brick dome, covered with a layer of stones. The floor is paved with tiles, and the wails are lined with them up to the springing of the dome ; a square hole being left in one side, furnished with a strong iron door, at which the liquid sulphur is drawn off" at proper intervals. In the roof of the vault are two valve-holes covered with light plates of sheet-iron, which turn freely on hinges at one end, so as to give way readily to any sudden expansion from within, and thus prevent dangerous explosions. As the chamber of condensation is an oblong square, terminating upwards in an oblong vault, it consists of a parallelopiped below, and semi-cylinder above, having the follow- ing dimensions : — Length of the parallelopiped Width .... Height . . . • Radius of the cylinder . . Height or length of semi-cylinder 16| feet. 16| Whenever the workman has introduced into each pot its charge of ten or twelve hun- dred weight of crude sulphur, he closes the charging doors carefully with their iron plates and cross-bars, and lutes them tight with loam. He then kindles his fire, and makes the GUNPOWDER. 975 sulphur boil. One of his first duties (and the least neglect in its discharge may occasion serious accidents) is to inspect the roof-valves and to clean them, so that they may play freely and give way to any expulsive force from within. By means of a cord and chain, connected with a crank attached to the valves, he can, from time to time, ascertain their state, without mounting on the roof. It is found proper to work one of the pots a certain time before fire is applied to the other. The more steadily vapors of sulphur are seen to issue from the valves, the less atmospherical air can exist in the chamber, and therefore the less danger there is of combustion. But if the air be cold, with a sharp north wind, and if no vapors be escaping, the operator should stand on his guard, for in such circum- stances a serious explosion may ensue. • As soon as both the boilers are in full work the air is expelled, the fumes cease, and every hazard is at an end. He should bend his whole attention to the cutting ofl* all com- munication with the atmosphere, securing simply the mobility of the valves, and a steady vigor of distillation. The conclusion of the process is ascertained by introducing his sounding-rod into the pot, through a small orifice made for its passage in the wall. A new charge must then be given. By the above process, well conducted, sulphurs are brought to the most perfect stat4, of purity that the arts can require ; while not above four parts in the hundred of the sul- phur itself are consumed ; the crude, incombustible residuum varying from five to eight parts, according to the nature of the raw material. But in the sublimation of sulphur, the frequent combustions inseparable from this operation carry the loss of weight in flowers to about twenty per cent. See Sulphur, for a figure of the subliming apparatus. The process by fusion, performed at some of the public works in this country, does not afibrd a return at all comparable with that of the above French process, though a much better article is operated upon in England. After two meltings of rough sul- fAur (as imported from Sicily or Italy), eighty-four per cent, is the maximum amount obtained, the average being probably under eighty ; while the product is certainly inferior in quality to that by distillation. 3. On tfie charcoal. — ^Tender and light woods, capable of afibrding a friable and porous • charcoal, which burns rapidly away, leaving the smallest residuum of ashes, and con- taining therefore the largest proportion of carbon, ought to be preferred for charring in gunpowder works. After many trials made long ago, black dogwood came to be preferred to every plant for this purpose ; but modern experiments have proved that many other woods afford an equally suitable charcoal. The woods of black alder, poplar, lime-tree, horse-chestnut, and chestnut-tree, were carbonized in exactly similar circumstances, and a similar gun- powder was made with each, which was proved by the same proof-mortar. The follow- ing results were obtained :— Poplar — mean range Black alder - Lime Horse-chestuut Chestnut-tree • 1 1 1 1 i 1 1 1 1 Toisea. f 66v« 113 .10 lU 110 109 2 4 3 3 By subsequent experiments, confirmatory of the above, it has been further found that the willow presents the same advantages as the poplar, and that several shrubs, such as the hazel-nut, the spindle-treee, the dogberry, the elder-tree, the common sallow, and some others, may be as advantageously employed. But whichever wood be used, we should always cut it when full of sap, and never after it is dead ; we should choose branches not more than five or six years old, and strip them carefully, because the old branches and the bark contain a larger proportion of earthy constituents. The branches ought not to exceed three quarters of an inch in thickness, and the larger ones should be divided lengthwise into four, so that their pith may be readily burned away. Wood is commonly carbonized in this country into gunpowder-charcoal in cast-iron cylinders, with their axes laid horizontally, and built in brick-work, so that the flame of a furnace may circulate round them. One end of the cylinder is furnished with a door, for the introduction of the wood and the removal of the charcoal ; the other end termi- nates in a pipe, connected with a worm-tub for condensing the pyroligneous acid, and giv- ing vent to the carbureted hydrogen gases that are disengaged. Towards the end of the operation, the connexion of the cylinder with the pyroligneous acid cistern ought to be cut off, and a very free egress opened for the volatile matter, otherwise the charcoal is apt to get coated with a fuliginous varnish, and to be even penetrated with condensable matter, which materially injure its qualities. I . 976 GUNPOWDER. In France, the wood is carbonized for the JTunpowder works either in oblong vaulted ovens, or in pits, lined with brick-work or cylinders of strong sheet-iron. In either case, the heat is derived from the imperfect combustion of the wood itself to be charred. In general, the product in charcoal by the latter method is from 16 to 17 parts, by weight, from 100 of wood. The pit-process is supposed to afford a more productive return, and a better article ; since the body of wood is much greater, and the fuliginous vapors are allowed a freer escape. The surface of a good charcoal should be smooth, but not glist. ening. See Charcoal. The charcoal is considered by the scientific manufacturers to be the ingredient most influential, by its fluctuating qualities, upon the composition of gunpowder; and, therefore, it ought always to be prepared under the vigilant and skilful eye of the director of the powder establishment. If it has been kept for some time, or quenched at first with water, it is unsuitable for the present purpose. Charcoal extinguished in a close vessel by exclusion of air, and afterwards exposed to the atmosphere, absorbs only from three to four per cent, of moisture, while red-hot charcoal quenched with water may lose by drying twenty-nine per cent. When the latter sort of charcoal is used for gun- powder, a deduction of weight must be made for the water present. But charcoal which has remained long impregnated with moisture, constitutes a most detrimental ingredient of gunpowder. 4. On mixing the Constitiunts and forming the Powder. The three ingredients thus prepared are ready for manufacturing into gunpowder. They are, 1. Separately ground to a fine powder, which is passed through sorted silk sieves or bolting machines. 2. They are nfixed together in the proper proportions, which we shall afterwards discuss. 3. The composition is then sent to the gunpowder mill, which consists of two edge-stones of a calcareous kind, turning by means of a hori- zontal shaft, on a bed-stone of the same nature ; incapable of affording sparks by col- lision with steel, as sand-stones would do. On this bed-stone the composition is spread, and moistened with as small a quantity of water as will, in conjunction with the weight of the revolving stones, bring it into a proper body of cake, but by no means into a pasty state. The line of contact of the rolling edge-stone is constantly preceded by a hard copper scraper, which goes round with the wheel, regularly collecting the caking mass, and bringing it into the track of the stone. From 50 to 60 pounds of cake are usually worked at one operation, under each millstone. When the mass has been thoroughly kneaded and incorporated, it is sent to the corning-house, where a separate mill is em- ployed to form the cake into grains or corns. Here it is first pressed into a hard firm mass, then broken into small lumps ; after which the corning process is performed, by placing these lumps in sieves, on each of which is laid a disc or fiat cake of lignum vitae. The sieves are made of parchment skins, or of copper, perforated with a multitude of round holes. Several such sieves are fixed in a frame, Avhich, by proper machinery, has such a motion given to it as to make the lignum vitse runner in each sieve move about with considerable velocity, so as to break down the lumps of the cake^ and fojxt its sub- stance through the holes, in grains of certain sizes. These granular 'particles are after- wards separated from the finer dust by proper sieves and reels. The corned powder must now be hardened, and its rougher angles removed, by causing it to revolve in a close reel or cask turning rapidly round its axis. This vessel resemi les somewhat a barrel-chum, and is frequently furnished inside with square bars parallel to its axis, to aid the polish by attrition. The gunpowder is finally dried, which is now done generally with a steam heat, or in some places by transmitting a current of air, previously heated in another chamber, over canvass shelves, covered with the damp grains. 5. On the proportion of the Constituents, A very extensive suite of experiments, to determine the proportions of the constituents for producing the best gunpowder, was made at the Essonne works, by a commission of French chemists and artillerists, in 1794. Powders in the five following proportions were prepared : — Nitre. CharcoAl. Sulphur. 1 76 14 10 Gunpowder of BAle. 2 76 12 12 Gunpowder works of Grenelle. 3 76 15 9 M. Guyton de Morvcau. 4 77-32 13-44 9-24 Idem. 5 77-5 15 7-5 M. Riffault. GUNPOWDER. 977 The result of more than two hundred discharges with the proof-mortar showed that the first and third gunpowders were the strongest; and the commissioners in conse- quence recommended the adoption of the third proportions. But a few years thereafter it was thought proper to substitute the first set of proportions, which had been found equal in force to the other, as they would have a better keeping quality, from containing a little more sulphur and less charcoal. More recently still, so strongly impressed have the French government been with the high value of durability in gunpowders, that they have returned to their ancient dosage of 75 nitre, 12| charcoal, and 12| sulphur. In this mixture, the proportion of the substance powerfully absorbent of moisture, viz., the charcoal, is still further reduced, and replaced by the sulphur, or the conservative ingre- dient. If we inquire how the maximum gaseous volume is to be produced from the chemical reaction of the elements of nitre on charcoal and sulphur, we shall find it to be by the generation of carbonic oxyde and sulphurous acid, with the disengagement of nitrogen. This will lead us to the following proportions of these constituents. 1 pnme equivalent of nitre - • - 1 sulphur 3 charcoal Hydrogen =s 1. Per cent 102 16 18 75-00 11-77 13-23 136 100-00 The nitre contains five primes of oxygen, of which three, combining with the three of charcoal, will furnish three of carbonic oxyde gas, while the remaining two will convert the one prime of sulphur into sulphurous acid gas. The single prime of nitrogen is, therefore, in this view, disengaged alone. The gaseous volume, on this supposition, evolved from 136 grains of gunpowder, cqui valent in bulk to 75| grains of water, or to three tenths of a cubic inch, will be, at the atmospheric temperature, as follows : — Carbonic oxyde .... Sulphurous acid .... Nitrogen - - . - . Grains. Cubic Inches. 42 = 141-6 32 = 47-2 14 = 47-4 236-2 being an expansion of one volume into 787*3. But as the temperature of the gases at the mstant of their combustive formation must be incandescent, this volume may be safely estimated at three times the above amount, or considerably upwards of two thou- sand times the bulk of the explosive solid. But this theoretical account of the gases developed does not well accord with Jie experimental products usually assigned, though these are probably not altogether exact. Much carbonic acid is said to be disengaged, a large quantity of nitrogen, a little oxyde of carbon, steam of watery with carbureted and sulphureted hydrogen. From experiments to be presently detailed, I am convinced that the amount of these latter products printed in italics must be very inconsiderable indeed, and unworthy of ranking in the calculation ; for, in fact, fresh gunpowder does not contain above one per cent, of water, and can therefore yield little hydrogenated matter. Nor is the hydrogen in the carbon of any consequence. It is obvious that the more sulphur is present, the more of the dense sulphurous acid will be generated, and the less forcibly explosive will be the gunpowder. This is suf- ficiently confirmed by the trials at Essonne, where the gunpowder that contained 12 of sulphur and 12 of charcoal in 100 parts, did not throw the proof-shell so far as that which contained only 9 of sulphur and 15 of charcoal. The conservative property is, however, so capital, especially for the supply of our remote colonies and for humid cli- mates, that It justifies a slight sacrifice of strength, which at any rate may be compen. sated by a small addition of charge. ; i .: I \i I I 1^1 978 GUNPOWDER. Table of Compontum^of different Gunpowders. Royal Mills at Wallham Abbey • France, national establishment French, for sportsmen French, for mining - - - United States of America - Prussia - - - - - Russia - - - - - Austria (^musqitet) - - - Spain . - - - - Sweden - - - - - Switzerland (a round powder) - Chinese - - - - - Theoretical proportions (as aboTe) Nitre. 75 75 78 65 75 75 73 72 76-47 76 76 75 75 Charcoal. 78 15 12-5 12 15 12-5 13-5 13-59 17 10-78 15 14 14-4 13-23 Sulphur. 10 12-5 10 20 12-5 11-5 12-63 16 12-75 9 10 9-9 11.77 6. On the Chemical Examination of Gunpowders. I nave treated five different samples : 1. The government powder made at Waltham Abbey; 2. Glass gunpowder made by John Hall, Darlford ; 3. The treble strong gun- powder of Charles Lawrence and Son; 4. The Dartford gunpowder of Pigou and Wilks; 5. Superfine treble strong sporting gunpowder of Curtis and Harvey. Ihe first is coarse-grained, the others are all of considerable fineness. The specific gravity of each was taken in oU of turnentine: that of the first and last three was exactly the samei».'*y in the same way, but no trace of mercury was obtained by the severest tests. Since by this process there is no doubt but one 10,000th part of fulminating mercury could be de- tected, we may conclude that Captain Vergnaud's charge is groundless. The superiority of our sporting gunpowders is due to the same cause as the superiority of our cotton fabrics— the care of our manufacturers in selecting the best materials, and their skill ia combining them. I shall subjoin here some miscellaneous observations upon gunpowder. 980 GYPSUM. GUTTA PERCHA. I In Bengal, mixing is performed by shutting up the ingredients in barrels, which are turned either by hand or machinery ; each containing 50 lbs. weight, or more,- of small brass balls. They have ledges on the inside, which occasion the balls and composition to tumble about and mingle together, so that the intermixture of the ingredients, after tne process has been eone through, cannot fail to be complete. The operation is con- imued two or three hours ; and I think it would be an improvement in Hier Majesty s svstemofmanufactureif this method of mixing were adopted. ' In En«»land two or three pints of water are used for a 42 lb. charge : but the quantity is varisWe ; both the temperature and the humidity of the atmosphere influence it. Bramah's hydrostatic press, or a very strong wooden press working with a powerful screw, lever, and windlass, constitutes the description of mechanism by which density is imparted to gunpowder. The incorporated or mill-cake powder is laid on the bed or follower of the press, and separated, at equal distances, by sheets of copper, so that when the operation is over, it comes out in large thin solid cakes, or strata, distinguished by the term press-cake. The mill-cake powder at Waltham Abbey, is submitted to a mean theoretic pressure of 70 to 75 tons per superficial foot.' r v * *i. ♦ Gunpowder should be thoroughly dried, but not by too high a degree of heat ; that of 140" or 150° of Fahrenheit's thermometer is sufllcient. It appears to be of no conse- quence whether it be dried by solar heat, by radiation from red-hot iron, as m the gloom Rtove, or by a temperature raised by means of steam. Her Majesty's gunpowder is dried by the last two methods. The grain should not be suddenly exposed to the highest degree ol heat, but gradually. .v j ^a,^.,^ «f The method of trial best adapted to show the real inherent strength and goodness of gunpowder, appears to be an eight or ten inch iron or brass mortar, with a truly spherical solid shot, having not more than one tenth of an inch windage, and fired with a low charge. The eight-inch mortar, fired with two ounces of powder, is one of the eslabUshea methods of proof at Her Majesty's works. Gunpowders that range equally in this mode of trial, may be depended on as being equally strong. r v^ Another proof is by four drachms of powder laid in a small neat heap, on a clean, PoUshed copper plate 3 which heap is fired at the apex, by a red hot iron. The explocMon shou 4 be sharp and quick ; not tardy, nor lingering; i^^hould produce a sudden concussion m the air f and the force and power of that concussion ought to be judged of by ^^P^^^J with that produced by powder of known good quality. No sparks should fly off, nor should beads, or globules of alkaline residuum, be left on the copper. If the copper be lelt clean, i. e. without gross foulness, and no lights, i. e sparks, be seen, Uie »n?'-edienU may be considered to'have been carefully prepared, and the powder to have been weU manipulated, particularly if pressed and glazed ; but if the contrary be the result, there has been a want of skill or of carefulness manifested in the manufacture. « Gunpowder," says Captain Bishop, « explodes exactly at the 600«> of heat by Fa^ renheit's thermometer; when gunpowder is exposed to 500° it alters its "f "^f ^l;^«- ther ; not only the whole of the moisture is driven off, but the saltpetre and sulphur arc aciuillv reduced to fusion, both of which liquefy under the above degree. The powder, on coofing, is found to have changed its color from a gray to a deep black j^he grain Hm oecome extremely indurated, and by exposure even to very moist air, it then suflers no alteration bv imbibing moisture." ,v r ii,.«r;n« The mill'for grinding the gunpowder cake may be understood from the louowing 981 rpmeaentation ( A<7. 740) ; p, is the water wheel, which may drive several pair.< of nLe^rrtwo vertical bevel wheels, fixed upon the axis of the great wheel- r. r. two horizontal bevel wheels working in q, q, and turning the shafts «, » ; t, t, two horizontal spur wheels fixed to the upper part of the vertical shafts, and driving the^arge wheeh i yJ"". *^^ -^""^^ ""^ ^^''' ^^"^'' ^^^^^ "^ fi^«^ the runners v, v, which traversl ur^n the bed stone «,, u, ; xz, are the curbs surrounding the bed stone to prevent the powdS bXt^ieTnd clirr ''' ""P"' """' ' "P"" ^^^ * '''^' ^"^ -" » a sec&'SS r..t7fT''^^' ^na/y*w of. M. Bolley dissolves out the sulphur from charcoal in gun- powder (previously freed from its nitre by water) by digesting it, at a boiling heat fS? 2 hours, with the solut on of 20 times its weight of^ufphite of 'sX, wh ch b thereby converted into hyposulphite To the mixture water must be added, as it is wasTed bv the boiling. I the residum be heated on platinum foU, it wiU exha e sulphuTff this had not been all removed by the sulphurous salt "«F"ur, u laia naa GUTTA PERCHA (Native). "Although the trees yielding this substance abound hv Dr w't "V*'' ^"^'^ Archipelago, the first notice tlken of it appears thavT^^ ^L? T ^''''ISomene, in a letter to the Bengal Medical Board, in the beu^nlin^f 1843, wherein he recommends the substance as likely to prove us;ful for some sir^ic^l taken to Europe by Dr. D Almeida, who presented it to the Royal Society of Arts of London, but it did not at first attract much attention, as the Society sim^y ^knowled^ed J^'n'^lilP^iS^ ^^ ^^* i '^}'''^^ .^^^^^^^ ^f*^' *h«y th^^gbt proper to a^^rdTgold mSlal to Dr. W. Montgomerie for a similar service. Now, as the discovery of Wh of ^he^ ftTnZT'!?'"^.P''"^J^V'^ "P"" '^^ same foundation, the accidS famt Tn wtth It m the hands of some Malays, who had found out its greatest peculiaritv a^d LvaM themselves thereof, manufactured it into whips, which ^ere broLht nto town f^ilf there does not appear any plausible reason for the passing over the first and rewlrdtt die second. Both gentlemen are highly to be comm^ended^for endeavoi^rirt^^ iTpr^^^! n"''*"^ A'*"^'r'" ^.^'"^ h«« P"-"^^^ «« "«^f"l and interesting! The gutS ^nhth!r«K^ rV\^ ^"i?'*'^ "'"'^ *'*^°*^«"' ^°d ^' y^t but little bf ng know^n o^ published about ,t. I would now propose to supply, to the best of my ability thUdesT deratum. and give a description of tW tree, its"^ product and uses, so for as ^i h^ ZZ made available for domestic and other purposes \n the place of its origfi The gutta percha. tree, or gutta tuban, as it ought more properly to be called th^ E^ .h f r^T^^ ^K;:"""' ^''l'^'^ ^^^°"^^ *« the nature far£ly%Vel but S.^ much from all described genera, having alliance with both ^cAra/and^a,Sa but diSn^ i^enT' fZ r hJT ^\'^^' ^ ""^ ^'^P^^^^ *« th'"k it » entitled rr^k La ne^ fl^L w f ' *'^"'^^«''^' endeavour to give its general character, leaving the honourTf nammg it to some more competent botanist, especially as I have not quiteltisfied mvL^f regarding the stamens, from want of specimens for observations ^ «atisned myself ' The tree is of a large size, from 60 to 70 feet in height,' and from 2 to 3 fp«t in diameter. Its general appearance resembles the genus Durio, or weH known 7>^ so much so as to strike the most superficial observer. ThfunTeV su7face of tL le^H^^^^^ "It is quite extraordinary how difficult it is to obtain specimens of either the flower or the fruit of this tree and this is probably the reason of its not havinrbLeuTar Her recognised and described by some of the many botanists who have visite these mrts "Only a short time ago the tuban tree was tolerably abundant on the . and oK L o pore ; but already all the large timber has been felled' and few. if any!o;her thL^^^^^^^^ p ants are now to be found. The range of its growth, however apDears to Kp o^^ T tie, it being found all up the Malayan Peninsula, \s Tar a;Tnrnywtr^Thr' ascertained it to be abundant ; although, as yet. the inhabitants do not stnToL aware of the faet. several of the mercantile houses there having sent down orders to Si^A^'e for supplies of the article, when they have the means of supplv close at ham? ^^^""P*"^® " The localities it particularly likes are the alluvial tracts alono- the foot of hills «.h»r. .t flourishes luxuriantly, forming, in many spots, the principal portion onLiunffl^B^ IS dSi'o'If ttiotr"">r "'T'" °' "■« ''*' "^ Wa^^-'" abundance a^ndwwi spread a.itusion, the gutta will soon become a verv scarrp nrtJ^lo ;r o,.r.,„ «,^ ^ • j . means ^be not adopted in its collection than thoTe^rp^^se^t'lTr^L^^^^^ - T\m mode in which the natives obtain the gutta is by cutting down the trees of full growth, and ringing the bark at distances of about 12 to 18 inches apart LidTlac nl a cocoa-nut shell, sp^the of a palm or such like receptacle, under the fallen J^^lt to receive the m.lky sap that mmediately exudes u^n every fresh InS ThU ap 18 collected in baniboos, taken to thetr houses, alid boile/ in order t«3rive off the watery parUcles and inspissate it to the consistence it finally assumes. A hou^S If. I . •J 982 GUTTA PERCHA. the Drocesa of boilincr appears necessary when the gutta is collected in large quantities. ^ a U^e be freS ly ^ounSed. a small quantity allowed to exude, and it be collected and moulded in the iSnd. it will consolidate perfectly in a few minutes, and have all the ^^r^rn^itltuitrpCelh^li" r is of a grayish white; but as brought to market, it is more ord nar?ly found of a reddish hue, arising from chips of bark that fall mto the sap n X act of mak^ing the incisions, and which yield their colour to it. Besides these acci- denUl chips there is a great deal of intentional adulteration by ^^Y^^^^ wto .„n materials. Some specimlns I have lately seen brought to market could not l^aye con- tS much less than i lb. of impurities ; and even in the purest specimens I could obut Tsurglal purpies. one pund of 'the substance yielded on being cleansed one ou^c^ of impurities^; fJrtunktely, U is neither difficult to detect or f^^^^%^l''^.?^^ foreign matter, it being only necessary to boil it n water until well softened, roll ou he eubsfance into thin sheets, and then pick out al impurities, which is easily done ate gutta does not adhere to anything, and all foreign matter is merely ent^^glf^^ "^/^^^ fibres, not incorporated in its substance. Tlie quantity of gutta obtained from each tree varies from 5 to^20 catties, so that, taking the average at 10 catties, which is a tolerably liberal one it will require the destruction of ten trees to produce one picul. JNow, the qSv eiporTed from Singapore to Great Britain and the continent, from 1st January ?8S o^heVesen^^^^^^^^^ f minted to 6,918 .iculs. to obtain which 69,180 trees must have been sacrificed. How much better would it, therefore, be to adopt the method ot tappin- the tree, practised by the Burmese in obtaining the caoutchouc from the Funs e£itica (yiz. to m^e oblique incisions in the bark, placing bamboos *« r^^^^^^ /^^ «*P which runs out freely), thii to kiU the goose in the manner they are at present doing ! ^e ihZ would not at first get so much from a single tree, but the ultimate gain would be incalculable, particularly as the tree seems to be one of slow growth; by no mearS so rapid as the ^icus elastica. I should not be surprised, if the demand increases and the pre^nt method of extermination be persisted m, to find a sudden cessation of the *""^rop^fi« of the 0^tta.-ThiB substance when fresh and pure is as already men- tioned. SI dirty white colour, and of a greasy feel, with a pecuhar leathery smell. It is not affected by boiling alcohol, but dissolves readily in boiling sp>nts of turpentine, also ?n naphtha an^d coal-tlr. A good cement for luting bottles and other purposes is forn^ed byWling together equal paFts of gutta and coal-tar and resm. I am indebted for this hfnt to Mr Little, surgeon, and the above were his proportions. I have, however, found it necessary o put two parts of the gutta, that is, one-half instead of one-th.rd. to enable the cement to^tand the heat of this climate. When reauired for use, it can Xays be made plastic by putting the pot containing it over the ^re for a few minutes. TheTutVa itself ^is highl v iuflammable ; a strip cut off takes ight and burns with a brifht flame, emitting sparks, and dropping a black residuum in the manner of seal- rnfwax, wbiJh in its combustion it very much resembles. But the great peculiarity of tlTis substance, and that which makes it so eminently useful for many purp<«e. L the effect of billing water upon it. When immersed for a few minutes m water above ?50° Fahr., it becomes sSt and plastic, so as to be capable of being moulded Tany required shape or form, which it retains upon cooUng. If a strip of it be cut off aU plunged into boiling water, it contracts in size both in length and breadth. This La very anomalous and remarkable phenomenon, apparently opposed to all the laws of ^'% is this plasticity when plunged into boiling water that has allowed of its being annliod to so many useful purposes, and which first induced some Malays to fabricate it Xwhips, whTh were brought into town, and led to its further notice. The natives have eXequen ly extended their manufactures to buckets, basins, and jugs, shoes traces, veSels for cooling wines, and several other domestic uses; but the number of patents [ately taken out for the manufacture of the article in England, provee how much atten- tion It has already attracted, and how extensively useful it is likely to become. Of all • the purposes, however, to which it may be adapted, none is so valuable as its applica- bilitrto the practice of surgery. Here it becomes one of the most useful auxilmries Tilt branch of the healing art which of all is the least coniectural. Its easy elasticity and power of retaining any shape given to it when cool, at once pointed Ft out as suitable for the manufacture of bougies ; and accordingly my predecessor Dr W Monttromerie, availed himself of this, made several of the above instruments, and recommended the use of it to the Bengal Medical Board. But, like many other good hbts Tr want of sufficient inquiry, I fear it was disregarded. The practice, how- eTer h^ been continued by me. and I find many advantages in the use of this sub- stance It also answers vefy well for the tubes of syringes, which are always gc t.ng out of' order in this country, when made of caoutchouc. But my late experiments have g?ven it a much higher value, and proved it the best and easiest application ever yet GUTTA PERCHA. 983 discovered in the management of fractures, combining ease and comfort to the patient, and very much lessening the trouble of the surgeon. When I think of the farrago of bandages and splints got rid of, the lightness and simplicity of the application, the gutta would be no trifling boon to mankind, were it to be used solely for this and no other pur- po.se. The injuries coming under my observation, wherein I have tested its utility, have, as yet, only been two compound fractures of the leg, and one of the jaw ; but so admira- bly has it not only answered, but exceeded my expectations, that I should think myself culpable in not giving the facts early publicity. Its utiUty in fracture of the lower jaw must at once strike any surgeon. So well does it mould itself to every sinuosity, that it is more like giving the patient a new bone than a mere support. A man lately brought into hospital, who had his lower jaw broken by the kick of a horse, and which was so severe as to cause haemorrhage from the ears, smashing the bone into several fragments, was able to eat and speak three days after the accident, and felt so well with his gutta splint that he insisted on leaving the hospital within ten days. My mode of applying this substance to fractures of the leg is as follows : — *• Tlie gutta having been previously rolled out into sheets of convenient size, and about one-fourth of an inch in thickness, is thus kept ready for use. When required, a piece of the necessary length and breadth is plunged into a tub of boiling water. TTie limb of the patient is then gently raised by assistance, making extension in the usual manner. The surgeon, having ascertained that the broken bone is in its place, takes the sheet of gutta out of the hot water, and allows it to cool for a couple of minutes. It is still soft and pliable as wash leather. Place it whilst in this state under the limb, and gently lower the latter down on it. The gutta is then to be brought round and moulded care- fully to the whole of the back and sides of the leg, bringing the edges close together, but not uniting them. If there be any superfluous substance, it can be cut off with scissors, leaving an open slit down the front of the leg. You have now the leg in a comfortable, soft, and smooth case, which in ten minutes will be stiff enough to retain any shape the surgeon may have given it, and which will also retain the bone in situ. Place the leg so done up on a double incline plane, and secure it thereto by passing three of the common loop bandages around the whole ; that is, one at the top, one in the middle, and one at the lower end. Let the foot be supported by a foot-board, and a case of gutta put over the dorsum of the foot, to bear off the pressure of the small bands generally used to secure it to the board. Having done this, the surgeon need not cause the patient another twinge of pain until he thinks he can use the leg, or he deems the bone sufficiently united to bear the weight of his patient. If it be a compound fracture, it will be only necessary to untie the loop bandages, separate the edges of the gutta splint to the required distance, wash and cleanse the limb without shifting any- thing except the dressings, and. having done so, shut it up again. The most perfect cleanliness can be maintained, as the gutta is not affected by any amount of ablution • neither is it soiled or rendered offensive by any discharge, all which washes off as easily from the gutta case as from oil-cloth. I have had a patient where the tibia protruded through the integuments fully two inches, walking about in six weeks from the injury, with a leg as straight and well formed as ever it had been. It is quite obvious, there^ fore, that if it answers so well for compound, it will answer equally, if not better, for simple fractures ; and that any broken bone capable of receiving mechanical support can be supported by the gutta better than by any other contrivance ; for it combines light- ness, and smoothness, and durability, and a capability of adjustment not possessed by any other known substance. All new experiments have to run the gauntlet of opposi- tion ; and I do not suppose that these recommendations will prove any exception to the rule ; but all I ask of any surgeon is, to try the experiment ere he argues on its pro- priety, and I feel fully convinced that all other splints and bandages will be consioned to the tomb of the Capulets. There are some other uses for which I have tried this'sub- etance, viz., as capsules for transmission of the vaccine virus, which ought to keep well when thus protected, for it is most perfectly and hermetically sealed ; but I have not had sufficient experience in this mode of using it to pronounce decidedly^ on its merits. I am at present trying the effects of it on ulcers, by enclosing the ulcerated limb in a case of gutta, so as to exclude all atmospheric air ; and so far, the experiment promises success. "Since writing the foregoing observations, I have had an official intimation from Penang, of the vaccine virus transmitted in the gutta capsules having been received in good order, and of its having succeeded satisfactorily. I have also opened a capsule containing a vaccine crust that had been kept here for one month, and it also seems to have lost none of its efficacy, as the case inoculated has taken. This Avill appear the more striking when it is recollected that, to preserve the vaccine virus hitherto in Singapore, even for a few days, has been almost impossible ; that this settlement, not- withstanding every exertion on the part of both private and public practitioners, ha* been without the benefit of this important prophylactic for an interval sometimes of two 984 GUTTA PERCHA. J .!,„» .. .11 limes the obtainins and transmitting this desirable remedy has years ; and that at ^' ''™f V^^'^,"" "o all the medical officers T have cter met with in Una cause oftroubk and d^fficuHy^^^^^ *'^'" »"' rl-iUf T/nin"; thel t^, ^aUotrntSn""' U^ having a disagreeable ??e smell, although peculfar, is neither strong ""^nP f*^ •. ^ d"a 1 ge & Again ; it appears to me that, >f.j¥ ^^^^^^^^^ I'JJa can be obtained here in a as being necessary for cleaning it is superfluous. ^J« ^""^ .f* ^i softened, and then perfectly pure state by simply boding it in hot ^?f ;,,""^ ^^j J^'^^'^ft;^^^^^ be easily rolled out Into thin sheets, xvl^en as I have ^^^^.^f/^^'/^/^'^'^e",^^^^^^^^ a higher Eiit^eTrd't^iimiirtLrtorirrc^'an^ -cot^torjer^XlumrT^^^^^^^^ ^r "oSchoic ^hen tLse materials have been mixed. ^^^ S^'CnoVaSS is to b^ l^iler and heated under pressure to a temperature of from 260° to 300 if. and " lo oe WHn this stlte for a period varying from half an hour to two hours, according to the t^ciness ofl^e mat?^^^^^^^^ prefers for eifecting the union of the sulphurous const.^ tnent the foCin^^^^^ to tl^e masticating machine. 1st. He subjects the purified Inni nTrcha tithe S)nioined action of steam and the fumes of orpiment and sjilphur lited^ th^'proportr^^ in a metal chamber, provided with a ^Jeam-tigh cover ^^rpdhv screw bolts. There is also a steam boiler comiected therewith, and wlien the wfnitiS to about 280° Fahr, a fire is lighted beneath the pot containing the ^ rl?2,rpd In from half an hour to two hours the sulphuring is finished. Or. the ftrl^roha mav £ Tubbed strongly over with the sulphurous mixture and then C^ted^ither SJ^or wiS the aid of ftU or coated in the form of a paste along with gutta percha „^„-_.i,.g inventions is to expose the gutta percha to the deutoxide of i^tr or cSoride'oT^i^^^^ andViling hit, anS then washed with ao GUTTA PERCHA. 985 alkaline solution or mere water. Gutta percha thus treated by the action of nitrous gas, as it is evolved from nitric acid and copper, iron, or zinc, becomes exceedingly smooth, and of a lustre approaching to metallic ; so also does common unsulphured caoutch(.uc. It is thus also freed from all stickiness: while the sulphured acquires under thi* treatment the d^wny softness of velvet. Chloride of zinc and nitrous gas remove the smell of vulcanized caoutchouc in a great measure, especially if it be afterwards Other new inventions are practised by masticating either gutta percha. caoutchouc, or jintawan, in the proportion of 6 parts with 1 of chloride of zinc; all which compounds may be afterwards sulphured. A further modification consists in producing a spongy gutta percha, caoutchouc, or jintawan. for stuffing sofas, olin<. The extraction is comp eted by returning the boiling alcohol several times upon tlfe gutta percha until it no longer dissolves anything. ^ The solid substance which has resisted the action of the solvent, possesses, with some modifications the principal properties of crude gutta percha; we shall here call it pnr- gutta or gutta As to the two other organic principles, one is a yellow resin whicli is much more soluble in cold alcohol than the other, xhe white crystallLZn By taking advantage of these different degrees of solubility, we are enabled with time and patience, to effect the complete purification of these three principS. ThT ei!ra r"r^ i""" be effected by treating finely-divided gutta percha with cold ether, ^Zch dissolves the mixture of the two resins more abundantly than alcohol; they are after wards separated from one another by the same treatment already descHbed for alcohol rhe tendency of the white resin to form itself into groups of radiated lamella is ma- nifested in a rather remarkable circumstance, vliich \t is easy to reproduce. Nar^t gI'^vITx ^71^'" ^ ^' "°^vith the rosearchos of M. Arppe on this subject See Chem. I 988 GUTTA PERCHA I I ribbons cut from a thin leaf of ordinary giitta percba are to be placed in a tube, and immersed in anhydrous alcohol. The tube is then closed, and left for twenty or thirty days, when a few whitish points appear here and there on the ribbons, and afterwards on the sides of the tube. These points, which become gradually larger, are formed of crys- talline tufts of the white resin. Thus this proximate principle is separated directly, and in the cold, even when the atmospheric temperature is gradually rising, for instance during the spring or early summer. The crystalline white resin, when completely purified by washings with alcohol, and then redissolved in anhydrous akohol, is deposited by slow spontaneous evaporation in the air, in radiated lamellar crystals, forming sometimes symmetrical tufts arranged in stars, and then presenting the appearance of a sort of eflflore'scence. Distinctive Characters and Properties of the Three Proximate Principles which consti- tute common Gutta Percha.—The most abundant of these three principles, forming at least from 15 to 82 per cent, of the whole mass, is the pure gutta, which presents the principal properties of the commercial substance ; it is white, transparent at a tempera- ture of 212° F., when all its parts are melted together; opake or semi-transpareut when cold, from its then acquiring a structure which causes the interposition of air, or of a licjuid possessing a different refraction from its own. Tliis stnicture appears still more distinct than in the natural substance containing all three principles. In thin sheets, and at a temperature of 50° to 68° R, it is supple, tough, extensible but not very elastic. At 112° R, it softens and turns back upon itself, and becomes more and more adhesive and translucent in proportion to the elevation of temperature, undergoing; a sort of doughy fusion, which becomes more distinct towards 212° to 230°. Heated beyond this point, it melts, boils and distils, furnishing a pyrogenous oil and carburetted gases. Pure gutta, like the other two proximate principjes, is quickly rendered electrical by friction, and is a bad conductor of heat ; it generally floats on water but sinks to the bottom as soon as its pores are filled with this liquid. It is insoluble in alcohol and ether, almost completely insoluble in benzine at 32° R, it is soluble at 77°, and becomes more and more so in proportion as the temperature is raised. The saturated solution at 86° forms itself into a semi-transparent mass when cooled below 32° ; alcohol precipitates the gutta from its solution in benzine. At 32°, spirits of turpentine dissolves very like gutta, whilst it disintegrates and dia* solves it readily when hot. Chloroform and sulphuret of carbon dissolve the gutta in the cold. After the extraction by means of ether of the two resins interposed in the thin leaves of white gutta percha, leaving the last portion of ether with which they were impregnated to evaporate in the open air, these leaves, enclosed in a flask, experienced, after remain- ing there for two months at a temperature of from 68° to 82° R, an alteration which appeared to depend on their porosity, the action of the air, and perhaps the ether retained in their pores. However it be, these leaves had then acquired new properties; the}' were brittle ; exhaled a very distinct sharp odour ; brought into contact with an excess of anhydrous ether, they were partially dissolved ; the soluble portion, obtained by the evaporation of the etherand desiccation at 194° F., was glutinous and translucent ; it became opake and hard by cooling down to 14° F. Sulphuret of carbon, renewed three times in six days, and evaporated each time after two days' contact, left as residue a white flexible leaf The portion not dissolved, swelled and transparent, did not appear to undergo any change when left in sulphuret of carbon for ten days. This kind of spontaneous transformation would perhaps become complete if more prolonged; its study will require much time; it will perhaps put us in the way of ascer- taining the causes of certain changes observed in some small objects formed of gutta percha. I have already been able to ascertain, that thin leaves, exposed for eight con- secutive days to the action of the sun in moist air, were discoloured, and that their sub- stance had become in great part soluble in ether. Monohydrated sulphuric acid disintegrates, and communicates a brown colour to the f)ure gutta, with evolution of sulphurous acid; after eight days' contact, the deep brown iquid, on dilution with water, becomes turbid, and furnishes a brown flocculent precipi- tate. Nitric acid, with a single equivalent of water, attacks the pure gutta with a lively effervescence, and the evolution of orange vapours of hyponitrous acid. Muriatic acid, in its saturated solution, slowly attacks the thin leaves of gutta, giving them a deep brown colour ; at the end of eight days it becomes friable. The reaction of muriatic acid estab- lishes an additional distinctive character between this proximate principle and the two others. Crystalline White Resin. — Obtained pure by means of the operations above described; it presents itself as a light pulverulent mass, apparently opake, which under the microscope exhibits the transparent lamellar crystals. From 82° to 212° F it does not GYr;SU.\I. 989 experience any sensible change; its fusion commences at 320*>; at 347° to 356° it acquires an oleiform fluidity and complete transparency, without any noticeable colour ; It solidifies on cooling, shrmks, which causes it to split, and remains transparent and a little heavier than water. The crystallized resin is very soluble in spirits of turpentine, in benzine, sulphuret of carbon, ether and chloroform ; on the spontaneous evaporation of the two last solvents. It crystallizes in long, narrow, thin, pearly laminae, forming separate groups radiating from common centres. o *- o r o Anhydrous alcohol dissolves it pretty readily at the temperature of 167° F.: on cooling, groups of crystals separate, which increase during several days • the cold solu- tion, decanted after crystallization, and left to spontaneous evaporation yields similar crops of more voluminous lamellae. ' These crystals are not attacked or readily moistened by either cold or boiling water as 18 also the case with hot or cold caustic alkaline solutions, ammonia, and the various dilute acids. Monohydrated sulphuric and nitric acids attack it rapidly producing similar phenomena to those observed in their action upon pure gutta. Muriatic aci and \r^%:i ancient. JMear JNorthwick the red marl beds above the great deposit of rock salt are irregularly intersected wih gypsum, in numerous lamina or plateT At Newbtjin [n ^nT^'i;lirp 'k1^ t.^^?Ti ^?i '" red argillaceous marl, between^wo strala of 3one and a mile south of Whitehaven, the subterraneous workings for the aUbas^ extend ♦ Chem. Qaz. vol Ir. p. 151. 990 GYPSUM. HADE. 991 »» SO yards in a direct line ; with two or three lateral branches extending about 10 yards., at whose extremities are lafge spaces where the gypsum is blasted with gunpowder. It is generally compact, forming a regular and conformable bed, with crystals of selenite (cr3rstallized gypsum) in drusy cavities. Gypsum occuis in the red marl in the isle of Axholme, and various other places in Nottinghamshire. In Derbyshire some consider- able deposits have been found in the same red sandstone, several of which are mined, as at Chellaston hill, which would exhibit a naked and water- worn rock of gypsum, were it not for a covering of alluvial clay. It appears in general to present itself chiefly in particular patches, occasioning a sudden rise, or an insulated hill, by the additional thickness which it gives to the stratum of the red ground in these places. The principal demand for the pure white gypsum, or that faintly streaked with reo, is by the potters in Staffordshire, who form their moulds with the calcined powder which it affords ; only particularly fine blocks are selected for making alabaster ornaments on the turning lathe. In one of the salt pits near Droitwich, the strata sunk through were vegetable mould, 3 feet ; red marl, 35 feet ; gypsum, 40 feet ; a river of brine, 22 inches ; gypsum, 75 feet ; a rock of salt, bored into only five, but probably extending much deeper. On the Welsh side of the Bristol Channel, gypsum occurs in the red marl cliffs of Glamor«janshire, from Pennarth to Lavernock. No organic remains or metallic minerals have hitherto been found in the gypsum of this formation. 3. The most interesting gypsums in a general point of view, are certainly the tertiary, or those of the plains, or hills of comparatively modern formation. They are characterized by the presence of fossil bones of extinct animals, both viammi/era and birds, by shells, and a large proportion of carbonate of lime, which gives them the property of effer- vescing with acids, and the title of limestone gypsums. Such are the gypsums of the environs of Paris, as at the heights of Montmartre, which contain crystallized sulphate of lime in many forms, but most commonly the lenticular and lance-shaped. Sulphate of lime occurs either as a dense compound without water, and is called anhydrite from that circumstance ; or with combined water, which is its most ordinary state. Of the latter there are 6 sub-species; sparry gypsum or selenite in a variety of crystalline forms ; the foliated granular ; the compact ; the fibrous ; the scaly foliated ; the earthy. The prevailing colour is white, with various shades of gray, blue, red, and yellow. More or less translucent. Soft, sectile, yielding to the nail. Specific gravity 2'2. Water dissolves about one five-hundredth part of its weight of gypsum, and acquires the quality of hardness, with the characteristic selenitic taste. When exposed on red hot coals, it decrepitates, becomes white, and splits into a great many brittle plates. At the heat of a baker's oven, or about 400° Fahr., the combined water of gypsum es- capes with a species of ebullition ; at a higher temperature the particles get indurated. When rightly calcined and pulverized, gypsum is mixed with water to the consistence of cream, and poured into moulds by the manufacturers of stucco ornaments and statues. A species of rapid crystallization ensues, and the thin paste soon acquires a solid consistence, which is increased by drying the figure in proper stoves. During, the consolidation of the plaster, its volume expands into the finest lines of the mould, so as to give a sharp and faithful impression. The plaster stone of the Paris basin contains about 12 per cent, of carbonate of lime. This body, ground and mixed with water, forms an adhesive mortar much used in building, as it fixes very speedily. Works executed with pure gypsum never become so hard as those made with the calcareous kind : and hence it might be proper to add a certain portion of white slaked lime to our calcined gypsum, in order to give the stucco this valuable property. Coloured stuccos of great solidity are maae by adding to a clear solution of glue, any desired colouring tincture, and mixing in the proper quan- tity of the calcined calcareous gypsum. The compact, fine-grained gypseous alabaster is often cut into various ornamental figures, such as vases, statuary groups, ^ "e (gum Senegal is sometimes used) a little iSeTwer'^u^rface "1'^?^"''"' " '"' "^'' "" '"^' ''' '''' ^'^^^^^ °^ ^^« ^ ^ ^^^ .«T^® ^^A i-/'?^" softened by exposure to steam, on the steaming basin, and is brushed and ironed K.1 it receives the proper gloss. It is lastly cut round at the brim by a knife toed at the end of a gauge, which rests against the crown. The brim, however, is not 4J HAT MANUFACTUKE. ^ 995 ihe turs and wools of which hats are manufactured contain in fhP.V *.arW «»««« «r whS tKaVlh^t er In'^ ^^ZTarfs X^ls^Z':^^^^^^^^^ Messrs. Parker and Harris obtained a patent in 1822 for the inrr, L T^ T^u an apparatus, whose structure and functLns may be peifect v uidlr^^^^^ T T ""^ T** organized combination which exists among journeyman hat^e?st by which the masters are held in a state of compSemiude LvL^^ *^ kingdom, single apprentice into their works beyond th dumber sS^ n P^"^" '^ '^^^ » of machine which is likely to supersede handla^or in anv r^^^^^^ "^^ *?J ^'' the hat trade is, generall/ speakLg, unproductfve to ?he caS^^^^^^ "?""" ceivmg any considerable develonrnpnt Th« «„ki:« r ^^P"^"st, and incapable of re- cay l« had of the bet ''U^yl; o^e^^^rpl^'o^TelTrS " """'""'• """" '""^ orT^ITni^h"! ''fS. Jirir?^.*?;; «"Sf\-l»-«-.-. ?e"-ny employed Fi,. m is the frameW „%UX;ruVn whTrZeTSS lathes are mounted, as a, b crown of the hat is to be iron'ed. ^Se iMhe b whe^ he^at m *" T.^'°^'^ "'™ "« .he brim is ironed, and lathe c, when its „„der'sWe?s roned motiZ I^^L""!*' ""' f whole by means of a band passing from any first moveJ7asa^t?»m.nSt'2* ^T" '? '^• &c.) to the drum on the main shaft a a Frim twrn™™ . f «a">-™gi«e, water-wheel, b,which actuates the axle of the lathe * O "to tWs latr, sor^o'f !S ■"" ""L"'^"! to the chuck the blocif <: is made fast by screws hilts or lilT tk- "k? •? «re"«i. and ed in section, in order to show tlie manner Tn',^^h » ^ a ^^f ""'''.'' l'V"SiecuX ^^Tni «« Tl f • ^^\ ^^ ^^^^^ "^^"^ ^^^ ^"^^'^ '^ blocks. «*'^e"'ons (varying as the carnage traverses), over the surface of the ord^r'to'wind JhtflirrJIfh 'S^n't ^' '^^'^^ ^"^^^^I '^"'^^' '' '^ — ^> - diameter of that part of thrWockwS \^f '""'.^? ^^,7 *^^"• '1^^ according to the givi,.g different veVit^s to the p\lTe;t ^''^ ^^ '""'''^^ »>y with . There is a similar coniL/^ Si t ^tatd^^ii'^ IZt tsUio'i T^^ 998 HAT MANUFACTURE. part of the frame, which is actuated by a band from any convenient part of the machine passing over a pulJej u upon the axle of t. From the drum /, ,o the drum I, ih°rc ^ a ^ the'le'^eit "^ * ° ^^ ^^^ ^"*'^^"'' °^ ^""^ rollers at the cad It will now be seen that when the larger diameter of the cam wheel o forces the lever outwards the band v will be guided on to the smaller part of the conical drum /and7l" larger part of 5, consequently the drum * will at this time receive its slowest motion anS the band g wtl turn the blocks slower also ; the reverse end of tL leverThlv^nTEy the same movement slidden the carriage into that position which causes the sUve?s to w nd upon the larger diameter of the blocks. severs 10 wina When the smaller diameter of the cam is acting against the side of the lever the weighted cord draws the end of the lever to the opposite side, and th^ band v wHl te guided on to the larger part of the cord t, and the smaller part of the cone , consLuentlv the quicker movement of the band g will now cause the Lcks . ' t^revoCwTa cor! responding speed. The carriage/ will also be moved upon its rollers, to the reverse X n? thP Kl 'T ""^ TV^y other material be now wound upon the smaller p.rte and ends of the blocks, at which time the quicker rotation of the blocks is required. It may b^ ent .h"at'd'h?n T' '^\ '""5 ""^"'^ ' ^^""^^ ^' ^'«'^''^"^'y ^^'^^ -^^«^ding to the diffe^ It only remains to state, that there are two heavy conical rollers w w, bearing upon the periphenes of the blocks e e, which turn loosely upon their axles by the frictbn of contac, for the purpose of pressing the slivers of wool or other material orihe blocks as It comes from the doffer cylinder of the carding engine, and Xn the Wocks have been coated with a sufficient quantity of the sliver, Ihe smal e^enHf the pressin' rollers IS to be raised while the cap is withdrawn from' the block The proces/^^^^^ After the caps or bodies of hats, &c. are formed in the above described machine ther are folded m wet cloths, and placed, upon heated plates, where they fre rolled u^der fZ™'*^' the purpose of being hardened. Fig. 748 'represents ^the fron of three furnaces a a a, the tops of which are covered with iron plates 6 6 b. Upon these 0^"^ which are bleated by the furnace below, or by steam, the bodies wrap^ in the w^t cloths cc c, are placed, and pressed upon by the flaps or covers d d d, sliding u^a S;"a^in'. "a'^/^MAr^"^ "f^ " ^--> ^^ '-eans of chains attaJhK an alternating bar e e. This bar is moved by a rotatory crank /, which has its motion by pulleys from any actuating power. When any one of the flaps is turn«iTntn r^ar;'' "^^ '"" '^"^^^'' ^^^ ^^^ ^-S ^--ly ' -d t'e fla^lemU^ These caps or hat bodies, after having been hardened in the manner above described may be felted in the usual way by hand, or they are felted in a Sg mT by the us^l rc"fumn^Tin'r."'""^'K'''' ''''':. '""V"' ^^^ ^«d'«^ "« oSi^ill?^ taken ou of the fulling mill, and passed between rollers, for the purpose of rendering the felt more "^^^ '^^^ Mr. Carey, of Basford, ob- tamed a patent in October, 1834, for an invention of certain ma- chinery to be employed in the manufacture of hats, which is ingenious, and seems to be worthy of notice in this place. It con- sists in the adaptation of a sys- tem of rollers, forming a machine^ by means of which the operation of roughing or plaiting of hats may be performed; that is, the beaver or other fur may be made to attach itself, and work into the felt or hat body, without the necessity of the ordinary manual fig- wo U . side elevatioD of the sa^e " /s/Vl ?''. wf, a'T"" ?^ ">«»?«"'"* ' i HAT MANUFACTURE. 999 Upon a brick or other suitable base, a furnace or fire-place a, is made, having a descend- ^^^ ing flue 6, for the purpose of cany. ing away the smoke. A pan or shallow vessel c c, formed of lead, is placed over the furnace ; which vessel is intended to contain a sou*- liquor, as a solution of vitriolic acid and water. On the edge of this pan is erected a wooden casing dd dj which encloses three sides, leaving the fourth open for the purpose of obtaining access to the working apparatus within. A series of what may be termed lantera rollers, € « «, is mounted on axles turning in the side casings; and another series of similar lantern rollers, / / /, is in like manner mounted above. These lantern rollers are made to revolve by means of bevel pinions, fixed on the ends of their axles, which are turned by similar bevel wheels on the lat- eral shafts g and h, driven by a winch t, and gear, as shown hi fig'- ^49 and 150, Having prepared the bodies of the hats, and laid upon their sur- faces the usual coatings of beaver, or other fur, when so prepared tltey are to be placed between hair cloths, a canvass or other suitable wrapper. Three or more'hltf bdn"?nc£^^^^^ wrapper, the packages are severally put into bags or pockets in an Pndtfc K»nT«f c u }^J^v ?-^' »"s[*"ce, for the purpose of merely attaching the furs to the felts Twhich ir caned slicking, when performed by hand), Mr. Carey prefer! to pass the endles Lnd i fe k with the covered hat bodies, over the upper series f f f nf thl io„* ! ii »antiAc/tft, to avoid the inconvenience of disturbingThe furwhfeh^4ht c^ rS ^i^g ?h1S the'lXr "" ''"' '"'^"^"'^ '^ ^^' P""' ^'^""'^ ^^« ^"^ ^^d become a^UcVc^ to After this operation of slicking has been effected, he distends the endless band kkk. over the lower series of lantern rollers e e «, and round a carrier rnllpr / odi, «, • J^ 751 ; and having withdrawn the hat bodies for the purposeT ra2ng\h^m^^^^^ ing their folds, he packs them again in a similar way in flannel, oimher stable cloil" and introduces them into the pockets or bags of the endless bands, as before ^ .»^"J"l''"^.i*'^"f'^J'*^''y ^» rotatory motion in the way described the hats will be carried along through the apparatus, and subjected to the scalding solu ion in ihe In « also to the pressure, and to a tortuous action between the ribs of the lantern rollers as Ihe^ revolve, which will cause the ends of the fur to work into the feltS Ses ofX h-»^^^ and by that means permanently to attach the nap to the body • an onP,^n Jl- J^ u ' * performed by hand, is called rolling off. ^ ' operation which, when The improved stiffening for hat bodies oroDospH hv Mw -ni- j j v January ,828, consists in making his s" uToHr'sh'iSl.f I„t'Sre",ey" nS' It spirits of wine, or pyroiylic spirit, vulgarly called naptha ^«""e 'ey. '"Stead of of ^alt^TSSlr'fcarnWS^^ t"- ^f '\ ^-^« be put into a kettle, and madrto b^il grad^alfy Ztif the !«; is S.?.nw'"' k "^.t"* liquor will become as clear as water, wfthout aVsuii'^pJS the op '^ni 7f feft 'tJ cool will have a thin crust upon its surface of a whitish caTmixed whh thl Lk. • purities of the gum When this skin is taken off, the hafbSy Is To be dlpi^'^lit the mixture in a cold state, so as to absorb as much as possible Vh ; or hmav^ applied with a brush or sponge. The hat body, being thus stiffened, may slndtill^ become dry or nearly so; and after it has been' brushed, it must be immLsed in ve^ dilute sulphuric or acetic acid, in ord.- to neutralize the po'tash, and caiTe Se shiSac 2 1000 HAT MANUFACTURE. •et. If the hats are not to be napped immediately, they may be thrown into a cistern of pure water, and taken out as wanted. Should the hat bodies have been worked at first with sulphuric acid (as usual), they must be soaked in hot water to extract the acid, and dried before the stiffening is applied care being taken that no water falls upon the stiffened body, before it has been immersed in the acid. This ingenious chemical process has not been, to the best of my knowledge, intro- duced into the hat manufacture. A varnish made by dissolving shellac, mastic, sand- arach, and other resins in alcohol, or the naptha of wood vinegar, is generally employed as the stiffening and water-proof ingredient of hat bodies. A solution of caoutchouc is oflen applied to whaletone and horse-hair hat bodies. The following recipe has been prescribed as a good composition for stiffening hats ; four parts of shellac, one part of mastic, one half of a part of turpentine, dissolved in five parts of alcohol, by agitation and subsequent repose, without the aid of heat. This stiffening varnish should be applied quickly to the body or foundation with a soft ob- long brush, in a dry and rather warm workshop ; the hat being previously fitted with its mside turned outwards upon a block. The body must be immediately afterwards taken off, to prevent adhesion. Hat-Dyeing.— The ordinary bath for dyeing hats, employed by the London manufacturers, consists, for 12 dozen, of— 144 pounds of logwood ; 12 pounds of green sulphate of iron, or copptitis ; 7f pounds of verdigris. The copper is usually made of a semi-cylindrical shape, and should be surrounded with an iron jacket or case, into which steam may be admitted, so as to raise the temperature of the interior bath to 190° F., but no higher, otherwise the heat is apt to affect the stiffening varnish, called the gum, with which the body of the hat has been imbued. The logwood having been introduced and digested for some time, the copperas and verdigris are added in successive quantities, and in the above proportions, along with cvAy successive two or three dozens of hats, suspended upon the dipping machine. Each set of hats, after being exposed to the bath with occasional airings during 40 minutes, is taken off the pegs, and laid out upon the ground to be more completely blackened by the peroxydizement of the iron with the atmospheric oxygen. In 3 or 4 hours the dyeing is completed. When fully dyed, the hats are well washed in running water. * Mr. Buffum states that there are four principal objects accomplished by his patent inven- tion for dyeing hats. 1. in the operation ; 2. the production of a better color; 3. the prevention of any of the damages to which hats are liable in the dyeing ; 4. the accomplishment of the dyeing process in a much shorter time than by the usual methods, and consequently lessening the injurious effects of the dye- bath upon the texture of the hat. Fig. 753 shows one method of constructing the apparatus, a a is a semi-cylindrical shaped copper vessel, with flat ends, in which the dyeing process is carried on. bbbia n wheel with several circular rims mounted upon arms, which revolve upon an axle c. In the face of these rims a number of pegs or blocks are set at nearly equal distances tpart, upon each of which pegs or blocks it is intended to place a hat, and as the whed HAT MANUFACTURE. 1001 i revolves, to pass it inio and out of the dyeing liquor in the vat or copper. This wheel may be kept revolving with a very slow motion, either by gear connecting its axlo, o, with any moving power, or it may be turned round by hand, at intervals of ten minutes : whereby the hats hung upon the pegs, will be alternately immersed for the space of ten minutes in the dyeing liquor, and then for the same space exposed to the atmospherir air. In this way, the process of dyeing, it is supposed, may be greatly facilitated and improved, as the occasional transition from the dye vat into the air, and from the air again into the bath, will enable the oxygen of the atmosphere to strike the dye more per feclly and expeditiously into the materials of which the hat is composed, than by a continued immersion in the bath for a much longer time. A variation in the mode of performing this process is suggested, and the apparatus Jig. 754 is proposed to be employed, a a is a square val or vessel containing the dyeing liquor ; 6 6 is a frame or rack having a number of pegs placed in it for hanging the hats upon, which are about to be dyed, in a manner similar to the wheel above described. This frame or rack is suspended by cords from a crane, and may in that way be lowered down with the hats into the vat, or drawn up and exposed in the air ; changes which may be made every 10 or 20 minutes. I have seen apparatus of this kind doing good work in the hat-dyeing manufactories of London, that being a department of the business with which the Union has not thought it worth their while to interfere. Mr. William Hodge's patent improvements in hat dyeing, partly founded upon an invention of Mr. Bowler, consist, first in causing every alternate frame to which the suspenders or blocks^ are to be attached, to slide in and out of grooves, for the purpose of more easily removing the said suspenders when required. Fig. 755 represents the improved dye- ing frame, consisting of two cir- cular rims, a a, which are con- nected together at top and bottom, by three fixed perpendicular bars or the frame-work 6 6 6. Two other perpendicular frames c c, similar to the former, slide in grooves, dd (f (2, fixed to the upper and lower rims. These grooves have anti-friction rollers in them, for the purpose of making the frames c c, to slide in and out more freely. The suspenders or substitutes for blocks, by these means, may be more easily got at by drawing out the frames c c, about half way, when the suspend- ers, which are attached to the frames with the hats upon them^ may be easily reached, and either removed or altered in position; and when it is done on one side, the sliding frame may be brought out on the other, and the remaining quantity of "suspenders" undergo the same operation. The patentee remarks, that it is well known to all hat dyers, that after the hats have been in the dyeing liquor some time, they ought to be taken out and exposed to the action of the atmospheric air, when they are again immersed in the copper, that part of the hat which was uppermost in the first immersion, being placed downwards in the second. This is done for the purpose of obtaining a uniform and regular dye. The patentee's mode of carrying this operation into effect, is shown in the figure : « « are pivots for the dyeing-frame to turn upon, which is supported by the arms /, from a crane above. The whole apparatus may be raised up or lowered into the copper by means of the crane or other mechanism. When the dyeing-frame is raised out of the copper, the whole of the suspenders or blocks are reversed, by turning the apparatus over upon the pivots e «, and thus the whole surfaces of the hats are equally acted upon by the dyeing material. It should be observed, that when the dyeing-frame is raised up out of the copper, it should be tilted on one side, so as to make all the liquor run out of the hats, as also to cause the rims of the hats to hang down, and not stick to the body of the hat, or leave a bad place or uneven dye upon it. The second improvement described by the patentee is the construction of " suspenders," to be substituted instead of the ordinary blocks. 1002 HATS. HATS. 1003 These " suspenders" are composed ot Ihin plates of copper, bent into the reqjired Ibrm, that is, nearly resembling that of a hat block, and made in such a manner as to he capable of contraction and expansion to suit different sized hats, and keep them distended, which may be altered by the workmen at pleasure, when it is required to place the hats upon them, or remove them therefrom. The dyeing-frame at fig. 546 is shown with only two of these " suspenders," in order to prevent confusion. One of these suspenders is represented detached at fig. 547, which exhibits a side view; and/ig. 548 a front view of the same. It will be seen by reference to the figure, that the suspenders consist of two distinct parts, which may be enlarged or collapsed by a variety of means, and which means may be suggested by any competent mechanic. The two parts of the suspenders are proposed to be connected together by arms g g, and at the junction of these arms a key is connected for turning them round when required. It will be seen oa reference to the front view, fig. 548, that the " suspenders" or substitutes for blocks, are open at the top or crown part of the hat; this is for the purpose of allowing the dyeing liquor to penetrate. From the mixture of copperas and verdigris employed in the hat-dye, a vast quantity of an ochreous muddy precipitate results, amounting to no less than 25 per cent, of the weight of the copperas. This iron mud forms a deposite upon the hats, which not only corrodes the fine filaments of the beaver, but causes both them and the felt stuff to turn speedily of a rusty brown. There is no process in the whole circle of our manufactures so barbarous as that of dyeing stuff hats. No ray of chemical science seems hitherto to have penetrated the dark recesses of their dye shops. Some halters have tried to remove this corrosive brown ochre by a bath of dilute sulphuric acid, and then counteract the evil effect of the acid upon the black dye by an alkaline bath ; but with a most unhappy effect. Hats so treated are most deceptions and unprofitable; as they turn of a dirfv brown hue, when exposed for a few weeks to sunshine and air. Hats. The body of a beaver hat is made of fine wool and coarse fur mixed and felted together, then stiffened and shaped ; the covering consists of a coat of beaver fur felted upon the body. Cheap hats have their bodies made of coarse wool, and their coverings of coarse fur or fine wool. The body or foundation of a good beaver hat, is at present made of 8 parts of rabbit's fur, 3 parts of Saxony wool, and 1 part of lama, vicunia, or red wool. About two ounces and a half of the above mixture are sufficient for one hat, and these are placed in the hands of the bower; his tool is a bow or bent ashen staff, from 5 to 7 feet long, having a strong catgut string stretched over a bridge at each end, and suspended at its middle by a cord to the ceiling, so as to hang nearly level with the work-bench, and a small space above it. The wool and coarser fur are laid in their somewhat matted state upon this bench, when the bower, grasping the bent rod with his left hand, and bij means of a small wooden catch plucking the string with his right, makes it vibrate smartly against the fibrous substances, so as to disentangle them, toss them up in the air, and curiously arrange themselves in a pretty uniform layer or fleece. A skilful bower is a valuable workman. The bowed materials of one hat are spread out and divided into two portions, each of which is compressed, first with a light wicker frame, and next under a piece of oil cloth or leather, called a hardening skin, till by pressing the hands backward and forward all over the skin, the filaments are linked together by their serrations into a somewhat coherent fleece of a triangular shape. The two halves or " bats" are then formed into a cap ; one of them is covered in its middle with a 3-cornered piece of paper, smaller than itself, so that its edges may be folded over the paper, and by overlapping each other a little, form a complete envelope to the paper; the junctions are then partially felted together by rubbing them hard, care being taken to keep the base of the triangle open by means of the paper ; the sec- ond bat being made to enclose the first by a similar process of folding and friction. This double cap, with its enclosed sheet of paper, is next rolled up in a damp cloth and kneaded with the hands in every direction, during which it is unfolded and creased up again in different forms, whereby the two layers get thoroughly incorporated into one body ; thus, on withdrawing the paper, a hollow cone is obtained. The above opera- tions have been partially described in the body of the Dictionary, and the remaining steps in making a hat are there sufficiently detailed. In a great hat factory women are employed, at respectable wages, in plucking the beaver skins, cropping off the fur, sorting various qualities of wool, plucking and cutting rabbit's fur, shearing the nap of the blocked hat, picking out unseemly filaments of fur, and in trimming the hats ; that is, lining and binding them. The annual value of the hats manufactured at present in the United Kingdom is estimated at 3,000,000/. sterling. The quantity exported in 1840, was 22,522 dozens, valued at 81,583/. With regard to the stiffening of hats, I have been furnished ^ya skilful operator with the following valuable information: "All the solutions of gums which I have hitherto seen prepar^ by hatters, have not been perfect, but, in a ceitain degree, a mixture, more or less, of the gums, which are merely suspended, owing to the consistency of the com- position. When this is thinned by the addition of spirit, and allowed to stand, it lets fall a curdy-looking sediment, and to this circumstance may be ascribed the frequent breaking of hata. My method of proceeding is, first to dissolve the gums by agitation in twice the due quantity of spirits, whether of wood or wine, and then, after complete solu- tion, draw off one-half the spirit in a still, so as to bring the stiffening to a proper consistency. No sediment subsequently appears on diluting this solution, however much it may be done. "Both the spirit and alkali stiffenings for hats made by the following two recipes, have been tried by some of the first houses in the trade, and have been much approved of : — Spirit Stiffening. 1 pounds of orange shellac. 2 pounds of gum sandarac. 4 ounces of gum mastic. Half a pound of amber rosin. 1 pint of solution of copaL 1 gallon of spirit of wine or wood naphtha. " The shellac, sandarac, mastic, rosin, are dissolved in the spirit, and the solution of copal is added last Alkali Stiffening. 7 pounds of common block shellac. 1 pound of amber rosin. 4 ounces of gum thus. 4 ounces of gum mastic 6 ounces of borax. Half a pint of solution of copal. " The borax is first dissolved in a little warm water (say 1 gallon) ; this alkaline liquor is now put into a copper pan (heated by steam), together with the shellac, rosin, thus, and mastic, and allowed to bod for some time, more warm water being added occaeionally until it is of a proper consistence ; this may be known by pouring a little on a cold slab somewhat inclined, and if the liquor runs off at the lower end, it is sufficiently fluid ; if, on the contrary, it set before it reaches the bottom, it requires more water. When the whole of the gums seem dissolved, half a pint of wood naphtha must be introduced, and the solution of copal ; then the liquor must be passed through a fine sieve, and it will be perfectly clear and readv for use. This stiffening is used hot. The hat bodies, before they are stiffened, should be steeped in a weak solution of soda in water, to destroy any acid that may have been left in them (as sulphuric acid is used in the making of the bodies). If this is not attended to, should the hat body contain any acid when it is dipped into the stiffening, the alkali is neutralized, and the gums consequently precipitated. After the body has been steeped in the alkaline solution, it must be perfectly dried in the stove before the stiffening is applied ; when stiffened and stoved it must be steeped all night in water, to which a small quantity of sulphuric acid has been added ; this set* the stiffening in the hat body, and finishes the process. A good workman will stiffen 15 or 16 dozen hats a day. If the proof is required cheaper, more shellac and rosin must be introduced." HEALDS, is the harness for guiding the warp threads in a loom; that is, for lifting a certain number of them alternately to open the shed, and afford passage to the decussating weft threads of the shuttle. See Weaving. HEARTH ; {Foyers Fr. ; Heerde, Germ.) is the flat or hollow space in a smelting fur- nace uptm which the ore and fluxes are subjected to the influence of flame. See CorrEii, Irov, Mktallurgt, - nitrate of silver, till the violet tint disappears. The preparations that follow may be applied to either the waxed or plain paper ; but in the latter case, the paper should be somewhat thick. First Preparation. — Negative Paper.— BoW in a porcelain or earthen pan, 3 litres of distilled water, with 250 grammes of rice, till this merely bursts, lest the water become* too glutinous. Strain through calico. Tliis forms an excellent size, and affords a g«K>d body and fine blacks. In a litre of the above rice water, dissolve 40 grammes of sugar of milk ; 15 of iodide of potassium ; 80 centigrammes of cyanide of potassium, and 50 cen- tigrammes of fluoride of potassium. Filter the solution, and set aside for use in a bottle. To prepare the paper, pour this solution into a large plate, and plunge the waxed paper into it, leaf by leaf over each other, taking care to expel the air bubbles. Take them out, return them for about half an hour ; then hang them up to dry, by means of a bent pin hooked to the corner ; and favour their drainage by placing a bit of blotting paper on their lower point This process is to be repeated. French and English papers should not be mixed in the same cistern. The English paper is said to contain a free acid, which precipitates iodide of starch in the French paper, and gives it a deep violet tint. The paper is to be cut down to the size of the camera obscura, and put up for use in a porte- feuille. The liquid which has been used will serve again. The paper thus prepared, is called iodized. Paper spceially for Portraiture — is prepared as follows. Take 400 grammes of dis- tilled water, 20 of iodide of potassium, 2 of cyanide of potassium, 0-50 centigrammes of fluoride of potassium ; — dissolve. Pour 2 or 3 millimetres of this solution into a flat plate of porcelain, or on a flat glass, quite horizontal. Take a piece of glazed paper by the two corners, the rough side uppermost, and apply the smooth fiice upon the liquid in the plate ; beginning the immersion with the side next your body, and pushing the leaf before you, so that it may always fall at right angles upon the liquid. Tliis movement is to be repeated two or three times, so as to press out any air bubbles. Take care that the liquid does not pass to the other side of the paper. It is to remain on the bath not more than two minutes at most. It is then to be lifted and perfectly dried between folds of blotting paper, of a fine tissue, rubbing it in all directions with the hands, and changing its place, that it may be perfectly dry. Remove the paper and smooth it with a soft brush. Lay the same side upon the bath of aceto-nitrate of silver (about to be indicated) ; leaving it there not more than 8 or 10 seconds at most, and then place it upon the slate in the camera, (which has been previously furnished with a leaf of blotting jxiper well Boaked in water, as will be described further on. It is requisite to make immediate use of this paper, because its great sensibility depends chiefly on the nascent state of the iodide of silver that it operates upon. In summer, from 4 to 10 seconds are required for an impression ; in winter, from 18 to 40. The second operation is to give sensibility to the iodized papers, either in the dry or humid wav. Take of - 150 grammes - 5 " Distilled water . - - Crystallized nitrate of silver When this is dissolved, add of crystallizable acetic acid 12 grammes. Care must be taken to prepare this solution by the light of a feeble taper, and to surround the phial with a case of blackened paper. No more of this mixture should be put into the cap. 1006 HELIOGRAPHY. fiule than is suflSeient for once. If not to be kept more than 4 days upon the paper, the following mixture may be used : Distilled water Acetate of silver Crystallizable acetic acid 150 grammes 10 12 " For the humid operation the paper may preferably be employed moist. At the moment of commencing, pour one of those mixtures of aceto-nitrate of silver upon a plate of porcelain or glass, quite horizontal, to about one millimetre in depth. A pipette or email sucking glass tube is convenient for this purpose, as its fine point prevents any drops from being spilled irregularly. And the surface of the liquid may be skimmed if neces- sary with a piece of white paper. The leaf of iodized paper is now to be seized by the two corners on the side only which was iodized, and to be laid down and raised several times so as to expel the air. This may be done with the thumb by the help of a pallet ivory knife to save staining the fingers. Take care that none of the nitro-acetate of silver goes on the other side of the paper. Allow the paper to receive the chemical action till the formation of a very sensible layer of cyano-iodo-fluoride of silver. Five minutes may suffice for the French paper, and a little longer for the English ; both being imbued with the sugar of milk preparations. Time should be given for the violet hue to disappear, — 4 or 5 minutes ; but with the portrait paper, 9 or 10 seconds should be sufficient. The longer this interval the less is the sensibility. Apply the paper quite moist upon a slate, on which there has been previously spread to receive it, a well soaked leaf of unsized paper. The sole of the camera may also be made use of, if it has been well covered with a coat of white wax. But the slate is preferable ; care being had to lay the surface with the aceto-nitrate uppermost to receive the radiations of light. The undermost piece of paper should be free from iron stains. The slate should be marked so as to be preserved always in one posture, both when they are applied and when put up in the frame. If these precautions be neglected, the liquid collects below and falls upon the prepared paper, and may cause spots. The paper, when thus put on the slate, may be left there for three or four hours without being removed, and may be placed during this interval in the camera. On going a little way off to take a proof, the fold of the leaf may be dipped in thick mucilage of gum-arabic, which serves to preserve the moisture and the adhesion. Two panes of glass may also be used for laying the papers between ; not sparing blotting paper in cleaning them. In the dry way, waxed paper is to be used. It will require more time to develop the image with the gallic acid ; but this comes out equally well, only there will be a pretty strong contrast between the whites and the blacks. The aceto-gallic acid, and the aceto- nitric, which are added should be fresh, extremely pure, and well filtered. Two porcelain basins of some depth are to be taken ; into the first put from 5 to 6 millimetres of accto- nitric acid (noted above) and into the second put distilled water. Plunge completely on the two sides the waxed and iodized paper, into the bath of the aceto-nitrate of silver of the first cistern, and leave it there 4 or 5 minutes, then transfer it immediately into the bath of distilled water in the second cistern, and leave it at least 4 minutes or more if you wish to keep the paper some time before using it. You may prepare next in the same baths, ten leaves one after the other. Lastly, the paper is to be taken from the water to be dried between folds of blotting paper, and laid by in a blotting-book equally dry. The paper is not to be dried by suspension in the air. Kept in the dark the paper will thus keep its qualities fully 5 days, before going into the camera The aceto-nitrate of silver deteriorates after 8 days. It is good not to put at once more than one or two proofs into the same bath of gallic acid. The period of exposure in the camera is not longer in the dry than in the humid way, but the proof must stand a little longer in the gallic acid, which may have 15 or 20 drops added to it of the nitro-acetate of silver filtered, and fresh made, or not previously used. The granular and soiled look of the paper under the gallic acid when it Decomes dry, should give no concern, as it disappears completely on re-melting the wax, of the proof on the exposure of its negative to a suitable heat. This precaution should never be neglected, for it is superior to any varnish. These operations being finished, invert the aceto-nitrate of silver into a phial, but don't reserve any for fresh proofs, which would prove a constant cause of failures. It may be thrown down by common salt, in the state of chloride of silver, which serves to give to hyposulphite of soda, the quality necessary for producing fine tones. The aceto-nitrate may be decoloured and revived by means of bone black, with which it is to be boiled a short time and then filtered. Third Operation : Exposure in the Camera. — Place the point of the image in the de- polished glass most scrupulously in the middle <»f the lens. After the exposure to the luminous rays the image in the camera has little appearance, being developed only by HELIOGRAPHY. 1007 the subsequent operation, which may be performed some hours afterwards, on the moist paper, or even some days with the waxed paper in the dry state. Development of the Image. — This is effected by the gallic acid diluted with pure water, in the proportion of 1 litre of the latter and 4 grammes of the former. Pour out of this solution into a horizontal flat shallow plate, to the thickness of 3 or 4 millimetres. Plunge the proof completely into it, so that it may be covered all round. Watch its development, which is readily perceived across the thickness of the paper. It may be left here from 10 minutes for an hour or two, till it be arrived at perfection. The development is much quickened by adding 20 or 21 drops of aceto nitrate of silver, when the image begins to appear. Very intense blacks are thus obtained, but the action must then be followed up, because it is rapid, and it gives such intense blacks, as to be disagreeable if the time be prolonged. When it is sufficiently deep, withdraw it smartly, and pour several streams of water over it, upon a plate or dish, rubbing the back of the paper at the same time with a finger to remove any crystalline grains which might spoil it. The gray hue of the waxed paper need cause no alarm as it disappears, and leaves beautiful whites and blacks. The tone which the image takes from the gallic acid will enable you to judge whether the exposure to the light has been adequate. If it becomes immediately of a gray black everywhere (looked well through), it shows it to have been too long under the light. If the greatest lights, which should be the greatest blacks of the negative, do not become deeper than the semi-tints, the exposure has also been too long. A first proof serves to regulate the time of exposure in the camera for the rest. Its period may be shortened by warming the gallic acid, for which a little appa- ratus has been used, consisting of a little square copper basin filled with water, supported over a small spirit lamp, which communicates heat to the shallow dish containing the gallic acid, 33 131,482 140,202 123,878 46,302 66,522 199,465 242,476 138,330 Yrs. 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 18.33 1834 1835 1636 1837 1838 1839 1840 1841 1842 Amount £154,609 203,724 26,058 148,832 24,317 269,331 140.848 172,027 38,398 88,047 174,864 139,018 156,905 189,713 235,207 200,332 178.578 171,556 205,5.37 34,09) 146,159 169,776 Hop duties of particular districts. Rochester Canterbury Kent Sussex Worcester Farnharn North Clays Essex Sundries 1839. £60.H02 16 50,649 3 6 111,451 19 65,026 19 16,639 16 7,730 2,005 1.624 1,058 6 7 4 2 10 9 5 205,538 12 7 1840. £23,256 19 8 5,757 4 29,014 3,080 12 9 239 " 1,643 18 57 4 35 17 1 20 4 8 19 p. t 1 34,091 17 2 1841. £51,490 3 8 33,960 14 10 85,450 18 6 38,086 13 10 ! 12,076 19 8 7,702 10 2 1,159 7 10 977 3 705 8 < 1842. £58,812 4 7 31,019 13 5 90,731 43,561 19,815 18 10 2 11 11, ^78 18 4 ) 1,724 2 7 2,050 19 11 203 14 ». 146,159 1 169,776 6 j HORDEINE is the name given b> Proust to the peculiar starchy matter of barley, k seems to bf a mixture of the starch, lignine, and husks, which constitutes barley meal. HORNVEne. and Germ. ; Come, Fr.), particularly ol oxen, cows, goats, and sheep, is a s^^iancfsoK tough, semi-transp'arent, and susceptible of ^tL'^'TurtL'S torts^ varitty of forms ; it is this property that distinguishes it from bone. TurUe or tortoise shell seems to be of a nature similar to horn, but instead of being of a uniform color, it is variegated with spots. These valuable properties render horn susceptible of being employed in a variety of works fit for the turner, snuff-box, and comb maker. The means of softening the horn need not be described, as it is well known to be by heat ; but those of cutting, polishing, and soldering it, so as to make the plates of large dimensions, suitable to form a variety of articles, may be detailed. The kind of horn to be preferred is that of goats and sheep, from its being whiter and more transparent than the horn of any other animals. When horn is wanted in sheets or plates, it must be steeped in water, in order to separate the pith from the kernel, for about fifteen days in sum mer, and a month in winter ; and after it is soaked, it must be taken out by one end, well shaken and rubbed, in order to get off the pith ; after which it must be put for half an hour into boiling water, then taken out, and the surface sawed even, length- ways ; it must again be put into the boiling water to soften it, so as to render it caqabie of separating ; then, with the help of a small iron chisel, it can be divided into sheets or leaves. The thick pieces will form three leaves, those which are thin will form only two, whilst young horn, which is only one quarter of an inch thick, will form only one. These plates or leaves must again be put into boiling water, and when they are sutficiently soft, they must be scraped with a sharp cutting instrument, to render those parts that are thick even and uniform; they must be put once more into the boiling water, and finally carried to the press. At the bottom of the press employed, there must be a strong block, in which i« formed a cavity, of nine inches square and of a proportionate depth ; the sheets of horn are to be laid within this cavity, in the following manner at the bottom : first a sheet of hot iron, upon this a sheet of horn, next again a sheet of hot iron, and so on, taking care to place at the top a plate of iron even with the last. The press must then be screwed down tight. There is a more expeditious process, at least in part, for reducing the horn into sheets, when it is wanted very even. After having sawed it with a very fine and sharp saw, the pieces must be put into a copper made on purpose, and there boiled, until suffi- ciently soft, so as to be able to split with pincers ; the sheets of horn must then be put m the press, where they are to be placed in a strong vice, the chaps of which are of iron and larger than the sheets of horn, and the vice must be screwed as quick and tight as possible ; let them cool in the press or vice, or it is as well to plunge the whole into cold water. The last mode is preferable, because the horn does not shrink in cooling. Now draw out the leaves of horn, and introduce other horn to undergo the same process. The horn so enlarged in pressing, is to be submitted to the action of the saw, which ought to be set in an iron frame, if the horn is wanted to be cut with advantage, in sheets of any desired thickness, which cannot be done without adopting this mode. The thin sheets thus produced must be kept constantly very warm between plates of hot iron to preserve their softness; every leaf being loaded with a weight heavy enough to prevent its warping. To join the edges of these pieces of horn together, it is necessary to provide strong iron moulds suited to the shape of the article wanted, and to place the pieces in contact with copper-plates or with polished metal surfaces against them ; when this is done, the whole is to be put into a vice and screwed up tight, then plunged into boiling water, and after some time it is to be removed from thence and immersed in cold water. The edges of the horn will be thus made to cement together and become perfect- ly united. To complete the polish of the horn, the surface must be rubbed with the subnitrate of bismuth by the palm of the hand. The process is short, and has this advantage, that it makes the horn dry promptly. When it is wished to spot the horn in imitation of tortoise-shell, metallic solutions must be employed as follows : — To spot it red, a solution of gold, in aqua re?ia, must be em|»loyed ; to spot it black, a solution of silver in nitric acid must be used ; and for brown, a hot solution of mercury in nitric acid. The right side of the horn must be impregnated with these solutions, and they will assume the colors intended. The brown spots can be produced on the horn by means of a paste made of red lead, with a solution of potash, which must be put in patches on the horn, and subjected some lime to the action of heat. The deepness of the brown shades depends upon the quantity of potash used in the paste, and the length of time the mixture lies on the horn. A de- coction of Brazil wood, or a solution of indigo, in sulphuric acid, or a deoclion of saflTron. and Barbary wood may also be used. After having employed these materials, the born may be left for half a day in a strong solution of vinegar and alum. In France, Holland, and Austria, the comb-maker and horn -turners use the clippings of horn, which are of a whiti.«h yellow, and tortoise-shell skins, out of which they make snuff-boxes, powder-horns, and many curious and handsome things. They first soften the horn and shell in boiling water, so as to be able to submit them to the press in iron 1 14 HORNSTONE. moulds, and by means of heat form them into one mass. Tlie degree of heat necessary to join' the horn clippings must be stronger than tliat for shell skins, and it can only be found out by experience. The heat must not however be too great, for fear of scorching the horn or shell Considerable care is required in these operations, not to touch the horn with the fingers, or with any greasy body, because the grease will prevent the perfect joining. Wooden instruments should be used to move them, while they are at the fire, and for carrying them to the moulds. In making a ring of horn for bell-pulls, r lliis, instead of having two distinct systems of thread, like the warp and the weft, which are woven together, by crossing each other at right angles, the whole piece is composed of a single thread united or looped together in a peculiar manner, which is called slocking-stitch, and sometimes chain-work. This is best explained by the view in fig. 760. A single thread is formed into a number of loops or waves, by arranging it _R over a number of parallel needles, as shown at "^ R : these are retained or kept in the form of loops or waves, by being drawn or looped through similar loops or waves formed by the thread of the preceding course of the work, s. The fabric thus formed by the union of a num ber of loops is easily unravelled, because the stability of the whole piece depends upon the ultimate fastening of the first end of the thread ; and if this is undone, the loops formed by that . end will open, and release the subsequent loops, one at a lime, until the whole is unravelled, and drawn out into the single thread from which It was made. In the same manner, if a thread in a stocking-piece fails, or breaks at any part, or drops a stitch, as it is called, it immediately produces a hole, and the ex- tension of the rest can only be prevented by fastening the end. It should be observed that there are many diflerent fabrics of stocking-stitch for various kinds of ornamental hosiery, and as each requires a diflferent kind of frame or machine to produce it, we should greatly exceed our limits to enter into a detailed description of them all. That species which we have represented in ^g. 760 is the common stocking-stitch used for plain hosiery, and is formed by the machine called the common stocking-frame, which is the groundwork of all the others. The operation, as we see, consists in drawing the loop of a thread successively through a series of other loops, so long as the woVk is continued, as is very plainly shown for one stitch in fig. 761. There is a great variety of diflerent frames in use for producing various ornamenUl kinds of hosiery. The first, which forms the foundation of the whole, is that for kniltins plain hosiery, or the common stocking-frame. Of this valuable machine, the invention of Mr. Lee, of Cambridge, a side elevation is given m fig. 762, with the essential parts. The framing is supjiorted by four upright posts, generally of oak, ash, or other hard wood. Two of these posts appear at a a, and the connecting cross rails are at c c. At b is a small additional piece of framing, which supports the hosier's seat. The iron-work of the machine is bolted or screwed to the upper rails of the frame-work, and consists of two parts. The first rests upon a sole of polished iron, which appears at d, and to which a great part of the machinery is attached. The other part, which is generally called the carriage, runs upon the iron sole at D, and is supported by four small wheels, or trucks, as they are called by the workn^en. At the upper part of the back standard of.iron are joints, one of which appears at q; and to these is fitted a frame, one side of which is seen exlendir.g to h. By means of these jmnts, the end at h may be depressed by the hosier's hand, and it returns, when relieved, by the operation of a strong spring of tempered steel, acting between a cross bar in the frame and another below. The action of this spring is very apparent in fig. 763. In the front of the frame, immediately opposite to where the hosier sits, are placed the needles which form the 'cops. These needles, or ralhei !t 1^ I' 1020 hooks, are Btocking ; HOSIERY. more or less numerous, and this, '762 according to although unavoidable, proves the coarseness or fineness of the a very considerable abatement of the value of a stocking-frame. In almost every other machine (for example, those employed in spin- ning or weaving), it is easy to adapt any one either to work coarser or finer work, as it may be wanted. But in the manu- facture of hosiery, a frame once finished, is limited for ever in its operation to the same quality of work, with this exception, that by changing the stuff, the work may be made a little more dense oi flimsy; but no alteration in the size or quantity of loops ^an take place. Hence where the manufacture is extensively pro- secuted, many frames may be thrown idle by every vicissitude of demand ; and where a poor mechanic does purchase his own frame, he is for ever limited to the same kind of work. The gauge, as it is called, of a stock- ing-frame is regulated by the .. . , - , , , , —^ number of loops contained in three mches of breadth, and varies very much ; the coarsest frames in common use being about what are termed Fourteens, and the finest employed in great extent about Forties. The needles are of iron wire, the manufacture of which is very simple ; but long practice in the art is found necessary before a needle-maker acquires the dexterity which will enable him both to execute his work well, and in sufficient quantity to render his labor productive. The process of making the needles is as follows :— Good sound iron wire, of a proper fineness, is to be selected ; that which is liable to split or splinter, either in filing, punching, or bending, being totally unfit for the purpose. The wire is first to be cut mto proper lengths, according to the fineness of the frame for which the needles are designed, coarse needles being considerably longer than fine ones. When a sufficient number (generally some thousands) have been cut, the wire must be softened as much as possible. This is done by laying them in rows in a flat iron box, about an inch deep, with a close cover ; the box being filled with charcoal between the strata of wires. This box, being placed upon a moderate fire, is gradually heated until both the wires and charcoal have received a moderate red heat, because, were the heat increased to what smiths term the white heat, the wire would be rendered totally unfit for the subsequent processes which it has to undergo, both in finishing and working. When the box ha« been sufficiently heated, it may be taken from the fire, and placed among hot ashes, until both ashes and box have gradually cooled; for the slower the wires cool, the softer and easier wrought they will be. When perfectly cool, the next process is to punch a longitudinal groove in the stem of every needle, which receives the point or barb, when depressed. This is done by means of a small engine worked by the power of a screw and lever. The construction of these engines is various; but a profile elevation of one of the most simple and com- monly used will be found in fig, 763. It consists of two very strong pieces of malle- able iron, represented at a and c, and these two pieces are connected by a strong well- fitted joint at B. The lower piece, or sole of the engine at c, is screwed down by bolts to a strong board or table, and the upper piece A will then rise or sink at pleasure, upon the joint B. In order that a may be very steady in rising and sinkin?, which is indispensable . . ^ . . to its correct operation, a strong bridle of iron, whicn is shown m section at e, is added to confine it, and direct its motion. In the upper part of this bridle is a female screw, through which the forcing screw passes, which IS turned by the handle or lever d. To the sole of the engine c is fixed a bolster HOSIERY. 1021 763 of tempered steel, with a small groove to receive the wire, which is to be punched ; and in the upper or moving part a, is a sharp chisel, which descends exactly into the groove, when a is depressed by the screw. These are represented at f, and above h. At g is a strong spring, which forces up the chisel when tho pressure of the screw is removed. The appearance of the groove, when the punching is finished, will be rendered familiar by inspecting fig. 764, p. 1022. When the punching is finished, the wires are to be brought to a fine smooth point by filing and burnishing, the latter of which should be very com- pletely done, as, besides polishing the wire, it tends greatly to restore that spring and elasticity which had been removed by the previous operation of softening. The wire is next to be bent, in order to form the hook or barb ; and this is done with a small piece of tin plate bent double, which receives the point of the wire, and by its breadth regu- lates the length of the barb. The stem of the needle is now flattened with a small hammer, to prevent it from turning in the tin socket in which it is afterwards to be cast ; and the point of the barb being a little curved by a pair of small pliers, the needle is coinpleteti. In order to fit the needles for the frame, they are now cast into the tin sockets, or leads, as they are called by the workmen ; and this is done by placing the needles in an iron mould, which opens and shuts by means of a joint, and pouring in the tin while in a stale of fusion. In common operations, two needles are cast into the same socket. The form of the needle, when complete and fitted to its place in the frame, will be seen iu fig. 765, which is a profile section of the needle-bar, exhibiting one needle. In this figure a section ol the pressure is represented at f; the needle appears at g, and the socket or level at k. At h, is a section of the needle-bar, on the fore part of which is a small plate of iron called a verge, to regulate the position of the needles. When placed upon the bar resting against the verge, another plate of iron, generally lined with soft leather, is screwed down upon the sockets or leads, in order to keep them all fast. This plate and the screw appear at i. When the presser at f is forced down upon the barb, this sinks into the groove of the stem, and the needle is shut ; when the presser rises, the barb opens ftgain by its own elasticity. The needles or hooks being all properly fitted, the next part of the stocking-frame to which attention ought to be paid, is the machinery for forming the loops ; and this con- sists of two parts. The first of these, which sinks between every second or alternate needle, is .epresented at o, fig. 762, and is one of the most important parts of the whole machine. It consists of two moving parts ; the first being a succession of horizontal levers moving upon a common centre, and called jacks, a term applied to vibrating levers in various kinds of machinery as well as the stockins-frame. One only of these jacks can be represented in the profile fig. 762 ; but the whole are distinctly shown in a hori- Eontal position in fig. 766 ; and a profile upon a very enlarged scale is given in fig. 767. jEi ? 766 ii 1022 HOSIERY. The jack shown in fig. 762, extends horizontally from o to i, and the centre of motion is at R. On the front, or right hand part of the jack at o, is a joint suspendins: a very thin plate of polished iron, which is termed a sinker. One of these jacks and sinkers is allotted for every second or alternate needle. The form of the sinker will appear at s, fig. 767 ; and in order that all may be exactly uniform in shape, they are cut oat and finished between two stout pieces of iron, which serve as moulds or gauges to direct the frame-smith. The other end of the jack at i, is tapered to a point ; and when the jacks are in their horizontal position, they are secured by small iron springs, one of which is represented at i, fig. 762, each spring having a small obtuse angled notch to receive the point cf the jack, against which it presses by its own elasticity. In^g. 767 the centre is at R ; the pointed tail is omitted for want of room, the joint is at o, and the throat of the sinker, which forms the loop, is at s. The standards at r, upon which the jack moves, are called combs, and consist of pieces of flat smooth brass, parallel to, and equidistant from each other. The cross-bar r, which contains the whole, is of iron, with a perpen- dicular edge or rim on each side, leaving a vacancy between them, or a space to receive the bottom part or tails of the combs. The combs are then placed in the bar, with a flat piece of brass called a countercomb, between each, to ascertain and preserve their distances from each other. These conntercombs are exactly of the same shape as the combs, but have no tails. When both combs and conntercombs are placed in the bar, it is luted with clay so as to form a mould, into which is poured a sufficient quantity of melted tin. When the tin has had time to cool, the countercombs having no tails are easily taken out, and the combs remain well fastened and secured by the tin, which has been fused entirely round them. Thus they form a succession of standards for the jacks ; and a hole being drilled through each jack and each comb, one polished wire put through, serves as a com mon centre for the whole. The jack sinkers being only used for every alternate or second needle, in order to complete this part of the apparatus, a second set of sinkers is employed. These are, in form and shape, every way the same as the jack sinkers, but they are jointed at the top into pieces of tin, all of which are screwed to the sinker bar h, fig. 762 ; and thus a sinker of each kind descends between the needles alternately. By these sinkers the loops are formed upon all the needles, and the reason of two sets different in operation being employed, will be assigned in describing the mode of working the frame. The presser of the operation, of which something has already been said, appears at f; and of the two arms which support and give motion to it, one appears very plainly at e, its centre of motion being at c. The circular bend given to these arms, besides having an HOSIERY. 768 A = B El TT n B 1 1 ]i.ii.i|.ii.!j.J-iHlH)-||-|-i-j-i-"-«-»-<^i -ii I W % 764 ornamental eifect, is very useful, in order to prevent any part from interfering with the other parts which are behind, by elevating them entirely above them. The extremities of these arms at the termination of the bends behind, are connected by a cross bar, which has also a circular bend in the middle, projecting down- wards, for a reason similar to that already assigned. This bend is concealed in fig. 762, but visible in the front elevation, fig. 768. From the middle of the bend, the presser is connected with the middle treadle by a depending wire appearing at Wjfig. 762, and thus, by the pressure of that treadle, the presser is forced down to close the barbs of the needle. The re-ascent of the presser is sometimes effected by means of a counterpoising weight passing over a pulley behind ; and some- times by the reaction of a wooden spring, formed of a strong hoop like that represented at k. The latter of these is preferred, espe- cially by the Nottingham hosiers, because, as they assert, it makes the presser spring up with greater 1023 rapidity, and consequently saves time in working. How far this may be praclichlly the case, it would be superfluous here to investigate ; but it is obvious that the wooden spring, if very stiff, must add much to the hosier's exertion of his foot, already exercised against the united sprin? of all his barbs; and this inconvenience is much complained of by those who have been accustomed to work with the counterpoise. At L are two pulleys or wheels, of different diameters, moving upon a common centre, by which the jack sinkers are relieved from the back springs, and thrown downwards to form the loops upon the needles. About the larger wheel is a band of whipcord, pass- ing twice round, the extremities of which are attached to what is called the slur, which disengages the jacks from the- back springs. The smaller pulley, by another band, communicates with the right and left treadle; so that these treadles, when pressed alternately, turn the pulleys about in an inverted order. The directions of these bands also appear more plainly in the front elevation, fig. 768. The construction of the slur, and its effect upon the jacks, will also be rendered apparent by fig. 769. In this figure, eight jacks are represented in section, the tail part of three of which, 1, 2, 3, are thrown up by the slur in its progress from left to right ; the fourth is in the act of rising, and the remaining four, 5, 6, 7, and 8, are still unacted upon, the slur not yei having reached them. As the slur acts in the direction of the dotted line x, x, fig. 766, behind the centres of the jacks, it is hardly necessary to remark, that this forcing up of the tails must of course depress the joints by which the sinkers in front are suspended. The jack sinkers falling successively from the loops on every alternate needle, in the way ^ f g represented at fig. 770, where both kinds of sinkers appear in section, the light part expressing what is above the point at which the throat of the sinker operates upon the thread, and the dark part what is below. The second set, or, as they are called, the lead sinkers, from the manner of i 770 ^^^^^^ I jointing them, and suspending them from the bar above, appear still elevated ; the position of the bar being represented by the line a, b. But when these are pulled down to the level of the former by the operator's hands, the whole looping will be completed, and the thread c, d, which is still slack, will be brought to its full and proper degree of tension, which is regulated by stop screws, so as to be tempered or altered at pleasure. The sinking of this second set of sinkers, may be easily explained by 771 /^^^^^N^ _-^x^ fig-'JIl. Thedirection of the sink- ers is expressed by the line e ; the bar from which they are suspended will be at A ; the top frame is in the direction from A to b; the back standards at d, and the joint at b, is the centre of motion. If e is pulled perpendicularly downwards, the spring c will be contracted, and its upper extreme point G, will be brought nearer to its lower extreme point f, which is fixed. Again, when the force which has depressed e is removed, the spring c will revert to its former state, and the sinkers will rise. The raising of the jack sinkers and jacks takes place at the same time, by the hosier raising his hands ; and for the cause of this we must revert to fig. 766. The lead sinkers in rising lay hold of notches, which raise the extreme parts of the set of jacks z, z, which are called half-jacks. Between the extremities of these at z, z, is a cross bar, which, in descending, presses all the intermediate jacks behind the common centre, and restores them to their original posture, where they are secured by the back springs, until they are again relieved by the operation of the slur recrossing at the next course. Working of the frame. — In order to work a frame, the whole apparatus being previ- ongly put into complete order, the hosier places himself on the seat b in front, and pro- vides himself with a bobbin of yarn or stuff. This bobbin he places loosely on a vertical pin of wire, driven into one side of the frame contiguous to the needles, so that it may turn freely as the stuff is unwound from it. Taking the thread in his hand, he draws it loosely along the needles, behind the barbs, and under the throats of the sinkers. He then presses down one of the treadles to pass the slur along, and unlock the jacks from the back springs, that they may fall in succession. When this is done, the number of loops thus formed is doubled by bringing down the lead sinkers, and the new formed loops are lodged under the barbs of the needles by bringing forward the sinkers. The preceding course, and former fabric, being then again pushed back, the barbs arc shut by depressing the middle treadle, and forcing down the presser upon the needles. The former work is now easily brought over the shut neeidles, after which by raising the i'i if 1024 HOSIERY. hands, both sets of sinkers are raised ; the jacks are locked by the back springs, and the hosier goes on to another course. From this it will be apparent, that the remark made in the outset is well founded, that there are, ia reality, no complicated or difficult movements in the stocking-frame. Almost the whole are merely those of levers moving upon their respective fulcra, excepting that of the carriage which gives the horizontal motion to the sinkers, and that is merely an alternate motion on four wheels. Yet the frame is a machine which requires con- siderable experience and care, both to work it to advantage, and also to keep it in good order. This circumstance arises greatly from the small compass in which a number of moving parts must be included. Owing to this, the needles, unless cautiously and deli- cately handled, are easily bent or injured. The same circumstance applies with equal or greater force to the sinkers, which must be so very thin as to be easily injured. But as these must work freely, both in a perpendicular and horizontal direction between the needles, in a very confined and limited space, the slightest variation in either, from beini? truly and squarely placed, unavoidably injures the others. When a hosier, either igno- rant of the mechanical laws, of their relation to each other, or too impatient to wait for the assistance of another, attempts to rectify defects, he in most cases increases them ten- fold, and renders the machine incapable of working at all, until repaired by some more experienced person. This circumstance has given rise to a set of men employed in this trade, and distinguished by the name of upsetters; and these people, besides setting new frames to work, have frequently more employment in repairing old ones injured by want of care or skill, than many country apothecaries, who live in unhealthy parishes, find in tampering with the disorders of mankind. It seems unnecessary to go further into detail respecting a machine so well known, and which requires practical attention even more than most others. It may, therefore, be sufficient to describe shortly some of its varieties, the most simple and common of which is the rib stocking-frame. Rib stocking-frame. — This frame, which, next to the common frame, is most exten- sively in use, is employed for working those striped or ribbed stockings, which are very common in all the different materials of which hosiery is formed. In principle it does not differ from the common frame, and not greatly in construction. The preceding gen- eral description will nearly apply to this machine with equal propriety as to the former; that part, however, by which the ribs or stripes are formed, is entirely an addition, and to the application of this additional machinery it may be proper to pay the chief atten- tion, referring chiefly to Jig. 768, which is a front elevation. This figure has been already referred to for the illustration of those parts of the machinery which are common to both, and those parts therefore require no reca- pitulation. The principle of weaving ribbed hosiery possesses considerable affinity to that which subsists in the weaving of that kind of cloth which is distinguished by the name of tweeling, for the formation of stripes, with some variation arising merely from the different nature of the fabric. In cloth weaving, two different kinds of yarn inter- secting each other at right angles, are employed ; in hosiery only one is used. In the tweeling of cloth, striped as dimity, in the cotton or kerseymere, and in the woollen man- ufacture, the stripes are produced by reversing these yarns. In hosiery, where only one kind of yarn is used, a similar effect is produced by reversing the loops. To effect this reversing of the loops, a second set of needles is placed upon a vertical frame, so that the bends of the hooks may be nearly under those of the common needles. These needles are cast into tin moulds, pretty similar to the former, but more oblique or bevelled towards the point, so as to prevent obstructions in working them. They are also screwed to a bar of iron, generally lighter than the other, and secured by means of plates : this bar is not fixed, but has a pivot in each end, by means of which the bar may have a kind of oscillatory motion on these pivots. The two frames of iron support this bar; that in which it oscillates being nearly vertical, but inclined a little towards the other needles. Fig. 772, which is a profile elevation, will serve to illustrate the relative position of each bar to the other. The lower or horizontal frame, the ends only of which can be seen in Jig. 768 under a a, appears in profile in Jig. 772, where it is distinguished by rf. The vertical frame at a is attached to this by two centre screws, which serve as joints for it to move in. On the top of this frame is the rib-needle bar at /, in Jigs. 762 and 772, and one needle is represented in Jig. 772 at /. At g is a small presser, to shut the barbs of the rib- needles, in the same manner as the large one does those of the frame. At h is one of the frame needles, to show the relative position of the one set to the other. The whole of the rib-bar is not fitted with needles like the other; for here needles are only placed where ribs or stripes are to be formed, the intervals being fillel up with blank leads, that is HOT-FLUE. 1025 to say, with sockets of the same shape as the others, but without needles ; being merely designed to fill the bar and preserve the intervals. Two small handles depend from the needle bar, by which the oscillatory motion upon the upper centres is given. The rising and sinking motion is communicated to this machine by chains which are attached ic iron sliders below, and which are wrought by the hosier's heel when necessary. The pressure takes place partly by the action of the small presser, and partly by the motion of the needles in descending. A small iron slider is placed behind the rib-needles, whidi rises as they descend, and serves to free the loops perfectly from each other. In the weaving of ribbed hosiery, the plain and rib courses are wrought a.ternately. When the plain are finished, the rib-needles are raised between the others, but no addi- tional stuff is supplied. The rib-needles, intersecting the plain ones, merely lay hold of the last thread, and, by again bringing it through that which was on the rib-needle be- fore, give it an additional looping, which reverses the line of chaining, and raises the rib above the plain intervals, which have only received a single knittin?. HOT-FLUE is the name given in England to an apartment heated by stoves or ateam pipes, in which padded and printed calicoes are dried hard. Fig. 773 represents the simplest form of such a flue, heated Ly the vertical round iron stove c, from whose top a wide square pipe proceeds upwards in a slightly inclined direction, which receives the current of air heated by the body and capital of the stove. In this wide channe there are pulleys, with cords or bands which suspend by hooks, and conduct the web of 1026 HOT-FLQE. ealico, from the entrance at b, where the operative sits, to near the point a, and back again. This circuit may be repeated once or oftener till the goods are perfectly dried. At D the driving pulley connected virith the main shaft is shown. Near the feet of the operative is the candroy or reel upon which the moist goods are rolled in an endless web; go that their circulation in the hot-air channel can be continued without interruption, a.^ long as may be necessary. Fig. 774 is a cross section of the apparatus of the regular hot-flue, as it is mounted 774 in the most scientific calico works of England, those of James Thomson, Esq., of Primrose, near Clilheroe, Lancashire, a a a a, is an arched apartment, nearly 30 yards long, by 13 feet high, and 10 feet wide. Through about one half of this gallery there is a horizontal floor sup- ported on arches, above which is the driest space, through which the goods are finally passed before they escape from the hot-flue, after they have been previously exposed to the hot but somewhat moist air of the lower compartment. A large square flue covered with cast-iron plates runs along the whole bottom of the gallery. It is divided into two loi.j, parallel vaults, whose sections are seen at i*, m, Jig. 774, covered with the cast-iron plates v v, grooved at their ends into one another. The thickness lof these plates is increased pro- gressively as they come nearer to the fire- place or furnace. There are dampers which regulate the draught, and of course the heat of the stove, h h are the air-passages or vent-holes, left in the side walls, and which by means of a long iron rod, mounted with iron plates, may be opened or closed together to any decree, fe k are the cast-iron supports of the tinned brass rollers which guide the goods along, and which are fixed to the cross pieces represented by r r, Jig. 774. 1 1 are iron bars for supporting the ventilators or fans (see the fan under Foundry). These fans are here enclosed within a wire grating. They make about 300 turns per minute, and expel the moist air with perfect effect, s indicates the position of the win- dows, which extend throughout the length of the building, t is & gas-light jet, placed at the side of each window to supply illumination for night work. The piece is stretched along the whole extent of the gallery, and runs through it in the course of one minute and a half; being exposed during its passage to the heat of 212° Fahr. In Jig. 775, A is the iron door of entrance to the hot-flue gallery ; at 6 is the pad- ding machine, where the goods are imbued with the general mordant. The speed of 775 this machine may be varied by means of the two conical drums c c, which drive it ; since when the band c c is brought, by its forks and adjusting screws, nearer to the narrow end of the lower drum, the cylinder upon the same shaft with the latter is driven quicker; and vice versa. Over d d the cords are shown for drawing the drum mechan- ism into gear with the main shaft band, r f e; or for throwing it out of gear. The pulleys F F carry the bands which transmit the motion to the padding machine. A cylindrical drum exterior to the hot-flue, covered with flannel, serves to receive the end of the series of pieces, and to draw them through the apartment. This mode of drying JACaUARD. 1027 the padded calicoes requires for each piece of 28 yards, 3 pounds of coals for the furnace when a fan is employed, and four pounds without it. HYDRATES ; are compounds of the oxides, salts, "^Soo^*^ o CP "O " O O 00 " i O 0O„O OOOo g o o o o"* O Co O O o oo. o o c ^ ri'J leaving open the corresponding holes, and covering those upon the face of the axis, which have no corresponding holes upon the card. . i • • i Now let us suppose mat tne press b is let down into the vertical position shown in fig. 778 ; then the card applied against the left face of the axis, leaves at rest or un- touched the whole of the horizontal spindles (skewers), whose ends correspond to these holes, but pushes back those which are opposite to the unpierced part of the card ; thereby the corresponding upright skewers, 3, 5, 6, and 8, for example, pushed out of the perpen- dicular, unhook themselves from above the bars of the claw, and remain in their place, when this claw comes to be raised by means of the lever g ; and the skewers 1, 2, 4, and 7, which have remained hooked on, are raised along with the warp threads attached to them. Then by the passage across of a shot of the color, as well as a shot of the common weft, and a stroke of the lay after shedding the warp and lowering the press b, an element or point in the pattern is completed. ■ c j ^^ x. The following card, brought round by a quarter revolution of the axis, finds all the needles in their first position, and as it is necessarily perforated diflferently from the pre- ceding card, it will lift another series of warp threads ; and thus in succession for all ihe Other cards, which compose a complete system of a figured /attern. This machine, complicated in appearance, and which requires some pains to be under- stood, acts however in a very simple manner. Its whole play is dependant upon the movement of the lever g, which the weaver himself causes to rise and fall, by means of a peculiar pedal ; so that without the aid of any person, after the piece is properly read in and mounted, he can execute the most complex patterns, as easily as he could weave plain goods ; only attending to the order of his weft yarns, when these happen to be of different colors. If some warp yarns should happen to break without the weaver observing them, or should he mistake his colored shuttle yarns, which would so far disfigure the pattern, he must undo his work. For this purpose, he makes use of the lower hooked lever /, whose purpose is to make the chain of the card go backwards, while working the loom as usual, withdrawing at each stroke the shot both of the ground and of the figure. The weaver is the more subject to make mistakes, as the figured side of the web is downwards, and it is only with the aid of a bit of looking-glass that he takes a peep of his work from time to lime. The upper surface exhibits merely loose threads in different points, accord- ing as the pattern requires them to lie upon the one side or the other. Thus it must be evident, that such a number of paste-boards are to be provided and mounted as equal the number of throws of the shuttle between the besinning and end of any figure or design which is to be woven; the piercing of each paste-board individually, will depend upon the arrangement of the lifting rods, and their connexion with the warp, JACQUARD LOOM. 1031 which is according to the design and option of the workman ; great care must be taken that the holes come exactly opposite to the ends of the needles; for this purpose two large holes are made at the ends of the paste-boards, which fall upon conical points, by which means they are made to register correctly. It will be hence seen, that, according to the length of the figure, so must be the number of paste-boards, which may be readily displaced so as to remount and produce the figure in a few minutes, or remove it, or replace it, or preserve the figure for future use. The machine, of course, will be understood to consist of many sets of the lifting rods and needles, shown in the diagram, as will be perceived by observing the disposition of the holes in the paste-board ; those holes, in order that they may be accurately distributed, are to be pierced from a gauge, so that not the slightest variation shall take place. To form these card-slips, an ingenious apparatus is employed, by which the proper steel punches required for the piercing of each distinct card, are placed in their relative situa- tions preparatory to the operation of piercing, and also by its means a card may be punched with any number of holes at one operation. This disposition of the punches is effected by means of rods connected to cords disposed in a frame, in the nature of a false simple, on which the pattern of the work to be performed is first read in. These improved pierced cards, slips, or paste-boards, apply to a weaving apparatus, which is so arranged that a figure to be wrought can be extended to any distance along the loom, and by that means the loom is rendered capable of producing broad figured works ; having the long lever g placed in such a situation that it affords power to the foot of the weaver, and by this means enables him to draw the heaviest morintures and figured works, without the assistance of a draw-boy. The machinery for arranging the punches, consists of a frame with four upright standards and cross-pieces, which contains a series of endless cords passing under a wooden roller at bottom, and over pulleys at the top. These pulleys are mounted on axles in two frames, placed obliquely over the top of the standard frame, wnich pulley frames constitute the table commonly used by weavers. In order belter to explain these endless cords, ^g. 784 represents a single endlest cord 1, 1, which is here shown in operation, and part of another endless cord 2, 2, shown stationary. There must be as many endless corda in this frame as needles in the weaving-loom, a 'a the wooden cylinder, revolving upon its axis at the lower part of the standards ; 66, the two pulleys of the pulley-frames above, over which the individual end- less cord passes ; c is a small traverse ring. To each of these rings a weight is suspended by a single thread, for the purpose of giving tension to the endless cord, d is a board resembling a common comber-bar, which is supported by the cross-bars of the standard frame, and is pierced with holes, in situation ani number, corresponding with the perpendicular threads that pass through them ; which board keeps the threads distinct from each other. At €, the endless cord passes through the eyes of wires resembling needles, which are contained in a wooden box placed in front of the machine, and shown in this figure in section only. These wires are called the punch-projectors ; they are guided and supported by horizontal rods and vertical pins, the latter of which pass through loops formed at the hinder part of the respective wires. At / are two horizontal rods extending the whole width of the machine, for the purpose of producing the cross in the cords ; g is a thick brass plate, extending along in front of the machine, and lying close to the box which holds the punch-projectors ; this plate g, shown also in section, is called the punch-holder ; it contains the same number of apertures as there are punch-projectors, and disposed so as to corres- pond with each other. In each of these apertures, there is a punch for the purpose of piercing the cards, slips, or pasteboards with holes; h is a thick steel plate of the same size as g, and shown likewise in section, corresponding also m its number of apertures, and their disposition, with the punch-projectors and the punch-holder. This plate A, is called the punch-receiver. The object of this machine is to transfer such of the punches as may be required for piercing any individual card from the punch-holder g, into the punch-receiver h ; when Ihey will be properly situated, and ready for piercing the individual card or slip, with 1032 ICE-HOUSE. I such holes as have heen read in upon the machine, and are required for permitting the warp threads to be withdrawn in the loom, when this card is brought against the ends of the needles. The process of transferring the patterns to the punches will be effected in the following manner. The pattern is to be read in, according to the ordinary mode, as in a false simple, upon the endless cords below the rods/, and passed under the revolving wooden cylinder a, to a sufficient height for a person in front of the machine to reach conveniently. He there takes the upper threads of the pattern, called the beard, and draws them forward so as to introduce a stick behind the cords thus advanced, as shown by dots, for the pur- pose of keeping them separate from the cords which are not intended to be operated upon. All the punch-projectors which are connected with the cords brought forward, will be thus made to pass through the corresponding apertures of the punch-holder g, and by this means will project the punches out of these apertures, into corresponding apertures of the punch-receiver h. The punches will now be properly arranged for piercing the required holes on a card or slip, which is to be effected in the following manner. Remove the punch-receivers from the front of the machine ; and having placed one of the slips of card or pasteboard between the two folding plates of metal, completely pierced with holes corresponding to the needles of the loom, lay the punch-receiver upon those perforated plates ; to which it must be made to fit by mortises and blocks, the cutting parts of the punches being downwards. Upon the back of the punch-receiver is then to be placed a plate or block, studded with perpendicular pins corresponding to the above described holes, into which the pins will fall. The plates and the blocks thus laid together, are to be placed under a press, by which means the pins of the block will be made to pass through the apertures of the punch-receiver ; and wherever the punch has been deposited in the receiver by the above process, the said punches will be forced through the slip of pasteboard, and pierced with such holes as are required for producing the figured design in the loom. Each card being thus pierced, the punch receiver is returned to its place in front of the machine, and all the punches forced back again into the apertures of tl ? punch holder as at first. The next set of cords is nove drawn forward by the next beard, at above described, which sends out Ihe pu7ich-projeciors as before, and disposes tht^punchev in the punch-receiver, ready for the operation of piercing the next card. The process being thus repeated, the whole pattern is, by a number of operations, transferred to the punches, and afterwards to the cards or slips, as above described. JADE, axe-stone (Nephrite, Ceraunile, Yr.), is a mineral co«nmonly of a greenish color, compact, and of a fatty lustre. Spec. Grav. 2-95 ; scratches glass, is very tough ; fuses into a white enamel. Its constituents are, silica, 50-5 ; alumina, 10; magnesia, iSl ; oxyde of iron, 5-50 ; oxj de of chrome, 0*05 ; water, 2-75. It comes from China, is used among rude nations for making hatchets; and is susceptible of being cut into any form. JAPANNING, is a kind of varnishing or lackering, practised with excellence by the Japanese, whence the name. See Varnish. JASPER (Jaspe calcedoine, Fr. ; Jaspis, Germ.) is a sub species of calcedt>ny quartz, of which there are five varieties. 1. The Egyptian red and brown, with ring or tendril- shaped delineations. 2. Striped jasper. 3. Porcelain jasper. 4. Common jasper. 5. Agate jasper. The prettiest specimens are cut for seals, and for the init/V)r kinds of jewellery ornaments. See Lapidary. ICE-HOUSE ; (Glaciere, Fr. ; Eishaus, Germ.) Under the article Freezing I have enumerated the different artificial methods of producing cold. But for the uses of com- mon life, in these climates, the most economical and convenient means of refrigeration in hot weather may be procured by laying up a store of ice in winter, in such circumstances as will preserve it solid during summer. An ice-house should not be regarded as an object of mere luxury, for pleasing the pal- ates of gourmands with iced creams and orgeats. In the southern countries of Europe it is considered among people in easy circumstances as an indispensable appendage to a country mansion. During the Dog-days, especially at those periods and in those dis- tricts where the sirocco blows, a lassitude and torpor of mind and body supei-vene, with indigestion or total loss of appetite, and sometimes dysenteries, :; :.ich are obviously oc- casioned by the excessive heat, and are to be prevented or countei acted chiefly by the us€ of cold beveraqes. By giving tone to the stomach, iced drinks immediately restore the functions of the nervous and muscular systems when they are languid ; while they enable persons in health to endure without much inconvenience an atmosphere so close and sultry as would be intolerable without this remedy. Ice-houses, moreover, afford to country gentlemen a great advantage in enabling them to preserve their fish, butcher meat, dead poultry, and game, which would otherwise, in particular states of the weather, immediately spoil. Considering at how little expense and trouble an ice-house can b< ICE PRODUCING MACHINE. 1033 constructed, it is surprising that any respectable haoitation m the country should not have one attached to it. The simplest and most scientific form is a double cone, that is, two cones joined base to base ; the one being of stones or brickwork, sunk under ground with its apex at the bottom, into which the ice is rammed ; the other being a conical roof of carpentry covered with thatch, and pointed at top. The entrance should be placed always on the north side ; it should consist of a corridor or porch with double doors, and be screened from the sunbeams by a sm?-ll shrubbery. Such are, in general, the principles upon which an ice-house should be formed ; but they will be better understood by the following explanation and figure. A dry sandy soil should be selected, and, if possible, a spot sheltered by a cliff or other natural barrier from the direct rays of the sun. Here a cavity is to be dug about 16 feet in diameter, terminating below like the point of a sugar loaf. Its ordinary depth, for a moderate family, may be about 24 feet ; but the larger its dimensions are, the longer will it preserve the ice, provided it be filled. In digging, the workman should slope the ground progressively towards the axis of the cone, to prevent the earth falling in. This conical slope should be faced with brick or stone work about one foot thick, and jointed with Roman cement so as to be air and water tight. A well is to be excavated at the bottom two feet wide and four deep, covered at top with an iron grating for supporting the ice, and letting the water drain away. The upper cone may likewise be built of brickwork, and covered with thatch ; such a roof would prove the most durable. This is the construction shown in Jig. 785. What ever kind of roof be preferred, there must be left in it an oblong passage into the interior. This porch should face the north, and be at least 8 feet long by 2^ feet wide ; and per- fectly closed by a well-fitted door at each end. All round the bottom of this conical cover, a gutter should be placed to carry off the rain to a distance from the ice-house, and prevent the circumjacent ground from getting soaked with moisture. Fig. 785 shows the section of a well-constructed ice-house. Under the ice-t,ham- ber A the ice is rammed into the space b. c is the grate of ths drain-sink d. Tht portion e e is built in brick or stone ; the base l of the ice-chamber slopes inwards to wards the ce^re at c. The upper part of the brickwork e £ is a little way below tne level of the ground. The wooden frame work F F F F forms the roof, and is covered with thick thatch. G H is the wooden work of the door i. Al K the bucket is seen for lifting up a charge of ice, by means of the cord J passing over the pulley m, which enables the servant to raise it easily. The icehouse should have no window to admit light; but be, so to speak, hermetically sealed in every point, except at its cess-pool, which ma) terminate in a water trap to prevent circulation of air. A clear day should be selected for charging the icehouse; but before beginning to fill, a quantity of long dry straw should be laid on the bottom crosswise; and as the ice is progressively introduced, straw is to be spread against the conical sides, to pre- vent the ice from coming into contact with the brick or stone work. The more firmly compacted the ict is, the better does it keep ; with which view it should be broken into pieces with mallets before being thrown in. No layers of straw should be stratified among the ice, for they would make its body porous. Some persons recommend to pour in a little water with the successive layers of ice, in order to fill up its small crevices, and convert the whole into one mass. Over the top layer a thick bed of straw should be spread, which is to be covered with boards surmounted with heavy stones, to close up the interstices in the straw. The inner and outer doors should never be opened at once ; but the one should always be shut before the other is opened. Dry snow well rammed keeps equally well with hard ice, if cpre be taken to leave no cavities in the mass, and to secure its compactness by sprinkling a little water upon the successive charges. To facilitate the extraction of the ice, a ladder is set up against its sloping wall at one side of the door, and left there during the season. ICE PRODUCING MACHINE. "It is well known that by the rapid condensation jt air or other elastic fluid, 5«> much heat may be evolved as to ignite tinder, «fcc. It appears from a comiuunicatiun in the Mechanics' Magazine of February, 1851, that Dr. Gi»rrie 1034 ILLUMINATION, COST OF. a pliysician iu New Orleans, has on this principle constructed an apparatus for producing so much cold as to freeze water, by exposure to the condensed air in the act of its subsequent expansion. Gay Lussac, many years ago, made use of a jet of condensed air to refrigerate any body such as a glass globe filled with water, upon which tlie ex- panding air was allowed to play, and he even caused water contained in the globe to freeze. Now the American process is quite identical with that of the Frencli chemist, but on a vastly enlarged scale, for he employs the power of a steam engine acting on a pump 8 inches in diameter, with a 16 inches stroke, to condense the air into one third Its volume, into a vessel, where it is cooled by water. A pump is made to throw in a jet of cold water at the same time to quicken the refrigeration. It is said that in this way a block of ice of 60 lbs. was formed ; a circumstance which appears to me quite incredible. In fact, the whole statement has a most apocryphal air, and I do not believe that any such result could have been produced, as the reporter says, by the labour of two men at a couple of pumps in alternate action. Tlio inventor's object at first was to ventilate and cool the atmosphere of sick rooms, where febrile patients lay. ** This case is one among the manv examples of a useful scientific invention remaining long dormant or sterile." The hydrostatic paradox of Archimedes is a parallel instance, in reference to Bramah's press. ICE BY THE RED-HOT PROCESS. One of the most singularly beautiful experiments perhaps ever devised, has been recently published by M. Prevostaire, illustrative of the repellent power of heat radiating from bodies at a high temperature, and of the rapid abstraction of heat, produced by evaporation, or generally by such a change of condition as largely increases the volume of any body. The experiment is simply this: — A platina crucible is made and maintained red-hot over a large spirit lamp. Some sulphurous acid is poured into it from a pipette. Tliis acid, though at common temperatures one of the most volatile of known bodies, possesses the singular property of remaining fixed in the red-hot crucible and not a drop of it evaporates : m fact, it is not in contact with the crucible, but has an atmosphere of its own in- terposed. A few drops of common water are now added to the sulphurous acid in the red-hot crucible. The diluted acid gets into immediate contact with the >beated metal, instantly flashes off into sulphurous acid vapoiu-, and such is the rapidity and energy of the evaporation that the water remains behind, and is found frozen into a lump of ice in the red-hot crucible, from which, seizing the moment before it again melts, it may be thrown out before the eyes of the astonished observer. JELLY, VEGETABLE, of ripe currants and other berries, is a compound of mucilage and acid, which loses its power of gelatinizing by prolonged ebullition. JELLY, ANIMAL ; see Gelatixe, Glue and Isinglass. JET ; (Jaiet or Jaia, Fr.) a species of pitch coal, or glance-coal, which, being found abundantly in a beautiful compact form, in the valley of Hers, arrondissement of Pa- miers, department of the Arri^ge, has been worked up extensively there, from time im- memorial, into a multitude of ornamental articles. With this black lignate, buttons, crosses, rosaries, necklaces, ear-drops, bracelets, waist-buckels, «. brilliancy, short of smoking, the relative illumination of the two lamps was determined by the well-known method of the comparison of shadows ; a wire a few inches long, and of the thickness of a crow-quill, being found suitable for enabling the eye to esti- mate very nicely the shade of the intercepted light. It was observed in numerous trials, both by my own eyes and those of others, that when one of the lamps was shifted half an inch nearer to or further from the paper screen, it caused a perceptible difference In the tint of the shadow. Professor Wheatstone kindly enabled me to verify the pre- cision of the above method of shadows, by employing, in some of the experiments, a photometer of his own invention, in which the relative brightness of the two lights was determined by the relative brightness of the opposite sides of a revolving silvered ball, illuminated by them. 1. The mechanical lamp was furnished with a glass chimney 1*5 inches in diameter at the base, and 1*2 at top; the wide bottom part was 1*8 inches long, and the narrow upper part 8 inches. When placed at a distance of 10 feet from the wall its light there may be estimated as the square of this number, or 100. In the first series of experi- ments, when burning with its maximum flame, with occasioned flickerings of smoke, it emitted a light equal to that of 11 wax candles, and consumed 912 grains of oil per hour. The sperm oil was quite pure, having a specific gravity of 0-874 compared to ILLUM [NATION, COST OF. 1037 water at 1,000. In a subsequent series of experiments, when its light was less flickering, and equal only to that of 10 wax candles, it consumed only 815 grains, or 0*1164 of a lb. per hour. If we multiply this number into the price of the oil (8*. per gallon) per lb. 1 Id., the product l*2804(f. will represent the relative cost of this illumination, esti- mated at 100. 2. The hot-oil lamp burns with a much steadier flame than the mechanical, which must be ascribed in no small degree to the rounded slope of the bell-mouthed glass chimney, whereby the air is brought progressively closer and closer into contact with the outer surface of the flame, without being furiously dashed against it, as it is by the rectangular shoulder of the common contracted chimney. When charged with sperm oil, and made to burn with its maximum flam.e, this lamp required to be placed one foot further from the screen than the mechanical lamp, in order that its shadow should have the same depth of tint. Hence, its relative illumination was, in that case, as the ■quare of 11 to the square of 10'; or as 121 to 100. Yet its consumption of oil was only 696 grains, or somewhat less than 0*1 of a pound per hour. Had its light been reduced to 100, it would have consumed only 576 grains per hour, or 0-82 of a pound. If we multiply this number by lid., the product 0*902d. will represent the relative cost of 100 of this illumination. 3. The hot-oil lamp being charged with the southern whale oil, of specific gravity 0'926, at 25. Qd. per gallon, or 3Jd. per lb., when burning with its maximum flame, required to be placed 9 feet and 1 inch from the screen to drop the same tint of shadow upon it as the flames of the other two lamps did at 10 and 1 1 feet with the sperm oil. The square of 9 feet and 1 inch = 82 is the relative illumination of the hot-oil lamp with the southern whale oil. It consumed 780 grains, or 0- J 1 1 of a pound per hour ; but had it given 100 of light it would have consumed 911 grains, or 0*130 of a pound, which number being multiplied by its price 3|i., the product 0*4875- portion of any one of the substances to be combined, when it is desired that the pecu- liar qualities of that substance shall predominate in the combined article. See Gutta Percha. IMPERMEABLE, is the epithet given to any kind of textile fabric, rendered water- proof by one or other of the following substances : — 1. Linseed oil to which a drying quality has been communicated by boiling with litharge or sugar of lead, met upon it much as upon common indigo. Chlorine, iodine, and bromine convert it mic a reddish brown soluble substance. Concentrated sulphuric acid, especially the smoking or anhydrous of Nordhausen, dissolves indigo-blue with the disengagement of heat, but it makes it suff'er some modification ; for though it retains an intense dark blue color, it has become soluble in water, and may be blanched by light, which does not happen with indigo itself. Nitric acid destroys indigo-blue, forms indigotic (carbazotic) acid, carbonic acid, artificial resin, and bitter principle. r n v Indigo-blue may be reduced by substances oxydized, with the co-operation of alkalis or alkaline earths; for example, by such substances as have a strong aflSnity for oxygen, and are imperfectly saturated with this principle, as the sulphurous and phosphorous acids and their salts, the proloxydes of iron and manganese, the proloxyde salts of tin, and the corresponding compounds of chlorine, as the prolo-chloi ides of lin and iron; and Ihe solution of the former in potash. When in these circumstances, in the presence of alkali, a deoxydation or reduction of the indigo-blue lakes place, the other bodies get oxydized by absorption of the oxygen of the indigo-blue ; the proloxydes become per- oxydes, and the acids in ous become acids in icy &c. Several metallic sulphurels also reduce the indigo-blue in the same predicament, as the sulphurels of potassium, of cal- 1048 INDIGO. m cium, of anvimony, and of arsenic (orpiment.) A similar influence is exercised by fer- menting vegetable substances, such as woad, madder, bran, raw sugar (molasses), starch, sirup, in consequence of the formation of carbonic and acetic acids, by absorption of the oxygen of the indigo-blue, for acetic acid and acetic salts are found in the liquor of the warm blue vat, in which indigo has been reduced by means of woad, madder, and bran. Formation of colorless reduced indigo-bine^ or indigotine. — Purified indigo-blue is to be treated with copperas and slaked lime, as above described ; or the clear wine-yellow supernatant liquor of the cold blue-vat mixture is to be taken, run by a syphon into a matrass, a few drops of concentrated acetic or sulphuric acid, deprived of air, are to be poured into it, and the vessel, being made quite full, is to be well corked. The reduced indigo soon falls in white flocks, or crystalline scales. They must be edulcorated upon a filter with water deprived of its air by boiling, then pressed between folds of blotting- paper, and dried under the receiver in vacuo. Indigo-blue may likewise be reduced and dissolved by solution of hydro-sulphuret of ammonia ; and the colorless indigotine maybe precipitated by muriatic acid. The reduced indigo is sometimes white at the instant of its elimination, sometimes grayish, of a silky lustre, but becomes very readily greenish, blue green, and blue, in the air ; in which case it absorbs, according to Berzelius, 4-2 per cent, of oxysen ; but ac- cording to Liebeg, 11*5 per cent. It is void of taste and smell, is insoluble in water; well boiled water free from air is not affected by it, but is turned blue by common water. It dissolves in alcohol and ether into a yellow dye ; not in dilute acids, but in concen- trated sulphuric acid, whereby probably a portion of this is decomposed, and some hypo- sulphurous acid formed; the color of this solution is blue. Solutions of the caustic and carbonated alkalis, even the alkaline earths, readily dissolve reduced indigo into a wine- yellow liquid; but in contact with air, oxygen is absorbed, and indieo-blue falls, while a purple-colored froth, passing into copper-red, appears "pon the surface, just as in the indigo vats of the dyer. The reduced indigo may be combined, by means of complex affinity, with other bases, with the exception of the oxydes of copper, zinc, and mercury, which oxydize it. These combinations are white, in part crystallizable, become speedily blue in the air, and afford by sublimation indigo-blue. Berzelius formed with lime a two-fold combination ; one easily soluble in water, and another difficultly soluble, of a lemon color, which contained an excess of lime ; this is formed both in the hot and the cold blue vat ; in the latter it is occasioned by an overdose of lime. When pure indigo-blue is treated with concentrated sulphuric acid, and particularly with six times its weight of the smoking dry acid, it dissolves completely, and several different compounds are produced in the solution. There is first a blue sulphate of indigo ; secondly, a similar compound with the resulting hyposulphurous acid; thirdly, a combination of sulphuric acid with the purple of indigo (called Phsenicin by Crum), a peculiar substance, generated from indigo-blue. These three compounds are here dissolved in an excess of sulphuric acid. The more concentrated the sulphuric acid is, the more blue hyposulphite is formed. The solution in smoking acid, when diluted with water and filtered, affords a considerable precipitate of indigo purple, which that in oil of vitriol does not. The vapoi of anhydrous sulphuric acid combines with indigo-blue into a purple fluid. In order to obtain from the dark blue solution each of these blue acids in a pure state, we must dilute it with forty times its weight of water, and immerse in the filtered liquor, well washed woo. or flannel, with which the blue acids combine, while most of the sulphuric acid and some other foreign substances remain free in the liquor. The wool must be then scoured with water containing about a half per cent, of carbonate of am- monia, or potash, which neutralizes both of the blue acids, and produces a blue compound, This being evaporated to dryness at the temperature of 140" F., alcohol of 0-833 is to be poured upon the residuum, which dissolves the blue hyposulphite, but leaves the blue sulphate undissolved. From either salt, by precipitating with acetate of lead, by acting upon the precipitate with sulphureted hydrogen water, and evaporation, either of the two blue acids may be obtained. They may be both evaporated to dryness, especially Ike blue sulphate of indigo ; they both become somewhat moist in the air, they are very soluble in water, and the blue sulphate also in alcohol; they have a not unpleasant smell, and an acid astringent taste. From these habitudes, particularly in reference to the bases, it appears that indigo-blue does not comport itself like a saline base towards the acids, but rather like an acM, since it enters into the salts, just as the empyreumatic oil of vinegar and oil of turpentine do into resin soaps. The blue pigment of both acids is reduced by zinc or iron without the disengagement of hydrogen gas ; as also by sulphureted hydrogen, tepid protochloride of tin, while the liquor becomes yellow. Indigo-bliie sulphate of potash, or ceruleo-sulphate of potash, may be obtained by extracting the blue color from the wool by water containing 1 per cent, of car- bonate of potash, evaporating nearly to dryness, treating the extract with alcohol INDIGO. 1049 to remove the indigo-blue hyjtosulphi/e, then with acetic acid and alcohol to remove any excess of carbonate of potash. It is found in commerce under the name of precipitated indigo, indigo paste, blue carmine, and soluble indigo. To prepare it economically, indigo is to be dissolved in ten times its weight of concentrated sulphuric acid; the solution after twenty-four hours is to ba diluted with ten times its weight of water, filtered, and imperfectly saturated with carbonate of potash ; whereby a blue pow- der falls down ; for the resulting sulphate of potash throws down the ceruleo-sulphate, while the hyposulphite of potash remains dissolved. It is a dark blue copper shining powder, soluble in 140 parts of cold water, and in much less of boiling water. It is made use of as a dye, and to give starch a blue tint. When mixed with starch ini cakes, it is sold under the name of 6/tt«for washerwomen. Ceruleo-sulphate of ammonia may be formed in the same way. It is much more soluble in water. Ceruleo-sulphate of lime is obtained by saturating the above dilute acid with chalk, filterin? to separate the undyed gypsum, and washing with water till the purple color be extracted. This liquor, evaporated and decomposed by alcohol, affords a bluish flocky precipitate, which is more soluble in water than common gypsum, and dries up in a purple-blue film. Ceruleo-sulphate of alumina may be obtained by double affinity; it is dark blue while moist, but becomes black-blue by drying, and is sol- uble in water. The blue present in all these salts of ceruUne is destroyed by sunshine, becomes greenish- gray by caustic alkalis ; and turns immediately yellow-brown by alkaline earths. But when the solution is very dilute, the color becomes first green, then yellow. The car- bonates of alkalis do not produce these changes. Nitric acid decomposes the color quickly. Mr. Crum considers ceruline to be a combination of indigo-blue with water. Phenicine, or indigo-purple combined with sulphuric acid, is obtained when the solution of indigo-blue in concentrated sulphuric acid has been diluted for a few hours with water, and then filtered. It seems to be an intermediate body into which the indigo-blue passes, before it becomes soluble ceruline. Hence it occurs in greater quantity soon after digestinsr the indigo with the acid, than afterwards. It is dark blue, dissolves gradually in water, affords after evaporation a blue residuum, of the same appearance as the above blue acids. When a salt is added to it a purple precipitate ensues, which is a compound of indigo-purple, sulphuric acid, and the base of the salt. Indigo-purple is reduced by bodies having a strong attraction for oxygen, if a free alkali or alkaline earth be present, and its solution is yellow, but it becomes blue in the atmosphere. According to Mr. Crum, Phenicine contains half as much combined water as ceruline. The table which I published in 1830 (as given above) shows very clearly how much the real quality and value of indigo differ from its reputed value and price, as estimated from external characters by the brokers. Various test or proof processes of this drug have been proposed. That with chlorine water is performed as follows. It is known that chlorine destroys the blue of indigo, but not the indigo-red or indigo-brown, which by the resulting muriatic acid is thrown down from the sulphuric solution in flocks, and the chlorine acts in the same way on the gliadine or gluten of the indigo. Pure indigo-blue is to be dissolved in 10 or 12 parts of concentrated sulphuric acid, and the solution is to be diluted with a given weight of water, as, for example, 1000 parts for 1 of indigo-blue. If we then put that volume of liquor into a graduated glass tube, and add to it chlorine water of a certain strength till its blue color be destroyed by becoming first green and then red-brown, we can infer the quantity of color from the quantity of chlorine water expended to produce the effect. The quantity of real indigo-blue cannot, however, be estimated with any accuracy in this way, because the other coloring matters in the drug act also upon the chlorine ; and, indeed, the indigo itself soon changes when dissolved in sulphuric acid even out of access of light, while the chlorine water itself is very suscej)tible of alteration. Perhaps a better appreciation might be made by avoiding the sulphuric acid altogether, and adding the finely powdered indigo to a definite volume of the chlorine water till its color ceased to be destroyed, just as Prussian-blue is decolored by solution of potash in making the ferro-cyanide. Another mode, and one susceptible of great precision, is to convert 10 or 100 graiu of indigo finely powdered into its deoxydized state, as in the blue vat by the proper quantity of slaked lime and solution of green sulphate; then to precipitate the indigo collect and weish it. The indigo should be ground upon a muller along with the quick- lime, ihe levigated mixture should be diluted with water, and added to the solution of the copperas. This exact analytical process requires much nicety in the operator, and can hardly be practised by the broker, merchant, or manufacturer. Employment of indigo in dyeing. — As indigo is insoluble in water, and as it can pene- trate the fibres of wool, cotton, silk, and flax, only when in a state of solution, the dyer must study to bring it into this condition in the most complete and economical manner This is effected either by exposing it to the action of bodies which have an affinity foi oxygen superior to its own, such as certain metals and metallic oxydes, or by mixing il 1050 INDIGO. with fermenting matters, or, finally, by dissolving it in a strong acid, such as the sulphuric. The second of the above methods is called the warm blue, or pastel vat ; and being the most intricate, we shall begin with it. Before the substance indiso was known in Europe, woad having been used for dyeins blue, gave ihe name of woad vats to the apparatus. The vats are sometimes made of copper, at other times of iron or wood, the last alone being well adapted for the employ- ment of steam. The dimensions are very variable ; but the following may be considered as the average size : depth, 7| feel ; width below, 4 feet, above, 5 feet. The vats are built in such a way that the fire does not aflTect their bottom, but merely their sides half way up; and they are sunk so much under the floor of the dyehouse, that their upper half only is above it, and is surrounded with a mass of masonry to prevent the dissipatior of the heat. About 3 or 3| feet under the top edge an iron ring is fixed, called the champagne by the French, to which a net is attached in order to suspend the stuflfs out of contact of the sediment near the bottom. In mounting the vat the following articles are required : 1. woad prepared by fermen lation, or woad merely dried, which is better, because it may be made to ferment in the ▼at, without the risk of becoming putrid, as the former is apt to do ; 2. indigo, previously ground in a proper mill; 3. madder; 4. potash; 6. slaked quicklime; 6. bran. Ir France, weld is commonly used instead of potash. The indigo mill is represented in Jigs. 790 and 791. a is a four-sided iron cistern 790 791 C J 4 c IffC 1, fl 4^hrjr>" cylindrical or rounded in the bottom, which rests upon gudgeons in a wooden frame ; it has an iron lid b, consisting of two leaves, between which the rod c moves to and fro, receiving a vibratory motion from the crank d. By this construction, a frame e, which is made fast in the cistern by two points e i, is caused to vibrate, and to impart its swing movement to six iron rollers///, three being on each side of the frame, which triturate the indigo mixed with water into a fine paste. Whenever the paste is uniformly ground, it is drawn oflT by the stopcock g, which had been previously filled up by a screwed plug, to prevent any of the indigo from lodging in the orifice of the cock, and thereby escaping the action of the rollers. The cistern is nearly three "eet long. The vat being filled with clear river water, the fire is to be kindled, the ingredients introduced, and if fermented woad be employed, less lime is needed than with the merely dried plani. Meanwhile the water is to be heated to the temperature of 160® Fahr., and maintained at this pitch till the deoxydizement and solution of the indigo begin to show themselves, which, according to the state of the constituents, may happen in 12 hours, or not till after several days. The first characters of incipient solution are blue bubbles, called the flowers, which rise upon the surface, and remain like a head of soap- suds for a considerable time before they fall ; then blue coppery shining veins appear with a like colored froth. The hue of the liquor now passes from blue to green, and an ammoniacal odor begins to be exhaled. Whenever the indigo is completely dissolved, an acetic smelling acid may be recognised in the vat, which neutralizes all the alkali, and may occasion even an acid excess, which should be saturated with quicklime. The lime for doing this cannot be in general very exactly defined. When quicklime has been added at the beginning in sufficient quantity, the liquor appears of a pale wine-yellow color, but if not, it acquires this tint on the subsequent introduction of the lime. Experience has not hitherto decided in favor of the one practice or the other. As soon as this yellow color is formed in the liquor, and its surface becomes blue, the vat is ready for the dyer, and the more lime it takes up without being alkaline, the better is its condition. The dyeing power of the vat may be kept up during six months, or more, according to the fermentable property of the woad. From time to time, madder and bran must be added to it, to revive the fermentation of the sediment, along with some indigo and potash, to replace what may have been abstracted in the progress of dyeing. The quantity of indigo must be proportional, of course, to the depth or lightness of the lints required. INDIGO. 1051 During the operation of this blue vat two accidents are apt to occur; the first, whick is the more common one, is called the throuring back, in French, the cuve rebiiti, and in German, the Scharf or Schwartzwerden (the becoming sharp or black) ; the second is the pulrefaciion of the ingredients. Each is discoverable by its peculiar smell, which it is impossible to describe. The first is occasioned by the employment of too much quick- lime, whereby the liquor becomes neutral or even alkaline. This fault may be recog- nised by the fading of the green, or by the dark green, or nearly black appearance of the liquor ; and by a dull blue froth, owing to a film of lime. The remedy for a slight degree of this vicious condition, is to suspend in the liquor a quantity of bran tied up in a bag, and to leave it there till the healthy state be restored. Should the evil be more invete- rate, a decoction of woad, madder, and bran must be introduced. Strong acids are rather detrimental. Sulphate of iron has been recommended, because its acid precipitates the lime, while its oxyde reduces the indigo to the soluble state. The decomposition or putrefaction of the blue vat is an accident the reverse of the preceding, arising from the transition of the acetous into the putrid fermentation, whereby the dyeing faculty is destroyed. Such a misfortune can happen only towards the com- mencement of working the vat, whilst the woad is still powerful, and very little indigo has been dissolved. Whenever the vat is well charged with indigo, that accident cannot easily supervene. In both of these distemperatures the elevation of the temperature of the vat aggravates the evil. Dyeing in the blue vat is performed as follows : — Wool is put into a net, and pressed down into the liquor with rods ; but cloth is smoothly stretched and suspended by hooks upon frames, which are steadily dipped into the va^ with slight motions through the liquor ; yarn-hanks must be dipped and turned about by hand. All unnecessary stirring of the liquor must however be avoided, lest the oxygen of the atmosphere be brought too extensively into contact with the reduced indigo, for which reason mechanical agitation with rollers in the vat is inadmissible. The stuffs to be dyed take at the first dip only a feeble color, though the vat be strong, but they must be deepened to the desired shade by successive immersions of fifteen minutes or more each time, with intervals of exposure to the air, for absorption of its oxygen. AAer the lapse of a certain time, if the fermentative power be impaired, which is re- cognised by the dye stuflfs losing more color in a weak alkaline test ley than they ought, the vat should be used up as far as it will go, and then the liquor should be poured away, for the indigo present is not in a reduced state, but merely mixed mechanically, and therefore incapable of forming a chemical combination with textile fibres. If cotton goods previously treated with an alkaline ley are to be dyed blue, the vat should contain very little lime. Theory of the. Indigo vat, — The large quantity of extractive matter in woad and madder, as also the sugar, starch, and gluten, in the bran and woad, Avhen dissolved in warm water, soon occasion a fermentation, with an absorption of oxygen from the air, but especially from the indigo of the woad, and from that introduced in a finely ground state. When thus disoxygenaled, it becomes soluble in alkaline menstrua ; ihe red-brown of the indigo being dissolved at the same time. When lime is added, the indigo-hlue dissolves, and still more readily if a little potash is conjoined with it; but whatever indigo-brown may have been dissolved by the potash, is thrown down by the lime. Lime ix\ too large a quantity, however, forms an insoluble combination with the reduced indigo, and thus makes a portion of the dye ineffective; at the same time it combines with the extractive. In consequence of the fermentative action, carbonic acid, acetic acid, and ammonia are disengaged ; the first two of which neutralize a portion of the lime, and require small quantities of this earth to be added in succession ; hence also a cou siderable quantity of tne carbonate of lime is found as a deposite on the sides and bottom of the vat. In the sound condition of the indigo vat, no free lime should be perceived, but on the contrary a free acid. Yet when the disengaged carbonic and acetic acids sat- urate the lime completely, no indigo can remain at solution; therefore a sufficient supply of lime must always be left to dissolve the dye, otherwise the indigo would fall down and mix with the extractive matter at the bottom. Goods dyed in the blue vat are occa- sionally brightened by a boil in a logwood bath, with a mordant of sulpho-muriate of tin, or in a bath of cudbear. Another mode of mounting the indigo vat without woad and lime, is by means of mad- der, bran, and potash. The water of the vat is to be heated to the temperature of 122° F. ; atid for 120 cubic feet of it, 12 pounds of indigo, 8 pounds of madder, and as much bran, are to be added, with 24 pounds of good potashes; at the end of 36 hours, 12 pounds more of potash are introduced, and a third 12 pounds in other 12 hours. In the course of 72 hours, all the characters of the reduction and solution of the indigo become apparent; at which time the fermentation must be checked by the addition of quicklime. The liquor has a bright full color, with a beautiful rich froth. In feeding the vat with indigo, an eciual weight of madder and a double weight of potash, should i 1 I 1052 INDIGO. it be added. The odor of this vat, in its mild but active stale, is necessarily different from that of the woad vat, as no ammonia is exhaled in the present case, and the sediment is much smaller. The reduced indigo is held in solution by the carbonated potash, while the small addition of quicklime merely serves to precipitate the indigo-brown. A potash vat dyes in about half the time of the ordinary warm vat, and penetrates fine cloth much better; while the goods thus dyed lose less color in alkaline and soap solutions. This vat may moreover be kept with ease in good condition for several months; is more readily mounted; and from the minute proportion of lime present, it cannot impair the softness of the woollen fibres. It is merely a little more expensive. It is said that cloth dyed in the potash indigo vat, requires one third less soap in the washing at the fulling mill, and does not soil the hands after being dressed. At Elbeuf and Louviers, in France, such vats are much employed. Wool, silk, cotton, and linen, may all be dyed in them. Cold vats. — The copperas or common blue vat of this country is so named because the indigo is reduced by means of the protoxyde of iron. This salt should therefore be as free as possible from the red oxyde, and especially from any sulphate of copper, which would re-oxydize the indigo. The necessary ingredients are: copperas (green sulphate of iron), newly slaked quicklime, finely ground indigo, and water; to which sometimes a little potash or soda is added, with a proportional diminution of the lime. The opera- tion is conducted in the following way : the indigo, well triturated with water or an alka- line ley, must be mixed with hot water in the preparation vat, then the requisite quantity of lime is added, after which the solution of copperas must be poured in with stirring. Of this preparation vat, such a portion as may be wanted is laded into the dyeing vat. For one pound of indigo three pounds of copperas are taken, and four pounds of lime (or 1 of indigo, 2^ of copperas, and 3 of lime). If the copperas be partially peroxydized, somewhat more of it must be used. A vat containir? a considerable excess of lime is called a sharp vat, and is not well adapted for dyeing. A sofi vat, on the contrary, is that which contains too much cop peras. In this case the precipitate is apt to rise, and to prevent uniformity of tint in the dyed goods. The sediment of the copperas vat consists of sulphate of lime, oxyde of iron, lime with indigo brown, and lime with indigo blue, when too much quicklime has been employed. The clear, dark wine yellow fluid contains indigo blue in a reduced state, and indigo red, both combined with lime and with the gluten of indigo dissolved. After using it for some lime Ihe vat should be refreshed or fed with copperas and lime, upon which occasion the sediment must first be stirred up, and then allowed time to settle again and become clear. For obtaining a series of blue tints, a series of vats of diiferent strengths is required. Linen and cotton yarn, before being dyed, should be boiled with a weak alkaline ley, then put upon frames or tied up in hanks, and after removing the froth from the vat, plunged into and moved gently through it. For pale blues, an old, nearly exhausted vat is used ; but for deep ones, a fresh, nearly saturated vat. Cloth is stretched upon a proper square dipping frame made of wood, or preferably of iron, furnished with sharp hooks or points of atiachment. These frames are suspended by cords over a pulley, and thus immersed and lifted out alternately at proper intervals. In the course of 8 or 10 minutes, the cloth is sufficiently saturated with the solution of indigo, after which it is raised and suspended so as to drain into the vat. The number of dippings determines the depth of the shade ; after the last, the goods are allowed to dry, taken off the frame, plunged into a sour bath of very dilute sulphuric or muriatic acid, to remove the adher- ing lime, and then well rinsed in running water. Instead of the dipping frames, some dyers use a peculiar roller apparatus, called gallopers, similar to what has been described under Calico Printing ; particularly for pale blues. This cold vat is applicable to cotton, linen, and silk goods. When white spots are to appear upon a blue ground, resist pastes are to be used, as described under Calico Printing. The urine vat is prepared by digestion of the ground indigo in wanned stale urine, which first disoxygenates the indigo, and then dissolves it by means of its ammonia. Madder and alum are likewise added, the latter being of use to moderate the fermenta- tion. This vat was employed more commonly of old than at present, for the purpose of dyeing woollen and linen goods. The mode of making the China blue dye has been described under Calico Printing ; as well as the pencil bhie, or blue of application. A blue dye may likewise be given by a solution of indigo in sulphuric acid. This pro- cess was discovered by Barth, at Grossenhayn, in Saxony, about the year 1740, and is hence called the Saxon blue dye. The chemical nature of this process has been already fully explained. If the smoking sulphuric acid be employed, from 4 to 5 parts are suffi- cient for 1 of indigo ; but if oil of vitriol, from 7 tc « parts. The acid is to be poured into an earthenware pan, which in summer must be placed in a tub of cold water, to pre- INDIGO. 1053 vent It getting hot, and the indigo, in fine powder, is to be added, with careful stirring, in small successive portions. If it becomes heated, a part of the indigo is decom- posed, with the disengagement of sulphurous acid gas, and indigo green is pnduced. Whenever all the indigo has been dissolved, the vessel must be covered up, allowed to stand for 48 hours, and then diluted with twice its weight of clear river water. The undiluted mass has a black bJue color, is opaque, thick, attracts water fiom the air, and is called indigo composition, or chemic blue. It must be prepared beforehand, and kept in store. In this solution, besides the cerulin, there are also indigo red, indigo- brown, and gluten, by which admixture the pure blue of the dye is rendered foul, as- suming a brown or a green cast. To remove these contaminations, wool is had recourse to. This is plunged into the indigo previously diffused through a considerable body of water, brought to a boiling heat in a copper kettle, and then allowed to macerate as it cools for 24 hours. The wool takes a dark blue dye by absorbing the indigo-blue sulphate and hyposulphite, while at the same time the liquor becomes greenish blue ; and if the wool be left longer immersed, it becomes of a dirty yellow. It must therefore be takeii out, drained, washed in running water till this runs oflf colorless, and without an acid taste. It must next be put into a copper full of water, containing one or two per cent, of carbonate of potash, soda, or ammonia (to about one third the weight of the indigo), and subjected to a boiling heat for a quarter of an hour. The blue salts forsake the wool, leaving it of a dirty red-brown, and dye the water blue. The wool is in fact dyed with the indigo-red, which is hardly soluble in alkali. The blue liquor may now be em- ployed as a fine dye, possessed of superior tone and lustre. It is called distilled blue and soluble blue. Sulphuric acid throws down from it the small quantity of indigo-red which had been held in solution by the alkali. When wool is to be dyed with this sulphate of indigo-blue, it must be first boiled in alum, then treated with the blue liquor, and thus several times alternately, in order to produce a uniform blue color. Too long continuance of boiling is injurious to the beauty of the dye. In this operation the woollen fibres get impregnated with the indigo- blue sulphate of alumina. With sulphate of indigo, not only blues of every shade are dyed, but also green, olive, gray, as also a fast ground to logwood blues ; for the latter purpose the preparatory boil is given with alum, tartar, sulphates of copper and iron, and the blue solution ; after which the goods are dyed up with a logwood bath containing a little potash. Table of Stocks, Deliveries, Imports, &c., through the course of 16 Yeara. Arrived in 19 moot lis. Crop of Prices 31»t December. Stock 31st December. Delivered 19 Months. Bt^n^il in course of Sbipinent. B.Dgal.* Madra.er lb. 6 0®6 e per lb. 6 4^5 10 5 6^ 6 • 1831 25,969 1H.544 19,409 9,162 22,111 113,600 1 4 " 8 9 6 3 " 6 9 183S 21,16) 28,488 21,610 2,812 23,688 8.1000 8 6 " 9 6 9 " 1 3 6 10 " 6 6 1839 15,250 23,211 13,8^2 3410 11 352 liS.OuO 8 8 " 9 6 " 1 6 " 5 9 1840 16,344 25,811 22,823 4.082 26.9 5 l-i3 0O0 1 6 " 8 3 6 3 " 6 3 4 6 « 5 1-^41 16,418 26.599 2. ',681 4.046 26.133 16. ,000 6 " 6 10 3 4 " 4 9 9 ♦ 3 3 1849 '.il,»21 91.820 26,594 6.rt15 33,269 18,900 1 9 •' 8 3 5 '• 5 9 4 3 " 4 9 1843 9l,:81 99.954 16,920 5888 92 808 lU.OOO 5 '• 5 8 3 6 " 3 10 9 10 •' 3 4 1844 25,<15 32,253 28.228 8,219 36 441 143 500 4 10 " 5 6 3 8 " 3 IL' ;: 9 " 3 6 1845 33.512 99.968 25,458 12,041 31 ,.'.05 191,800 4 10 " 5 8 3 3 " 3 6 9 10 " 3 3 1846 3;M18 28.431 19,4:;8 8 659 28,09 J 101 300 6 " 6 3 8 " 4 3 9 " 3 6 1841 31,909 31.428 19.516 9,516 29,152 1O1.200 4 6 " 6 3 2 10 " 3 3 9 4 " 9 8 1848 28.962 215t.3 21,119 3.504 24. 62.5 126100 4 3 " 5 3 9 10 " 3 3 fi 6 •» 9 9 1849 29 036 39.113 97,464 5383 3 -■841 122,(H.0 4 6 " 6 4 3 6 " 3 9 3 3 " 3 6 18.'>0 21.2<"5 98.69.) 20,051 6,809 96,859 11 2,' too 6 '• 1 5 9 " 5 6 4 1 " 5 1861 30,33* 99,241 92,612 9,196 32.368 122,OoO 4 8 " 5 9 3 1 " 3 11 3 1 " 8 « Stock of E. I. Indigo, in the chief European Ports, at the end of the following Years. Yearf. Rotter- dam,* Amster- dam.* Antwerp. Ham- burgh, St. Peters- burgh. Trieste. Genoa. Bremen. Fiance. London and Liverpool. ToUl Stock in Europe. I84S 1844 1<45 184H 1S41 1848 1849 1860 1861 cllfStS. 1,500 664 5.S0 331 93^ 1049 695 395 80 cliests. 1,600 1,342 651) 499 560 531 828 851 320 chests, loo no 100 100 60 60 100 160 loO chests. 255 850 320 916 160 450 550 840 960 chests. 1,701 1600 9,011 1,389 1918 9,000 1.655 l,4fi0 1,681 chests. 150 949 980 400 930 900 160 150 60 chests. 149 9o6 9.6 165 13) 120 101 40 60 chests. 20 10 60 50 9) 48 90 60 90 chests. 6.466 1,:i9 10,485 10 615 ll.lil 1.4rt9 4,501 5,311 6,953 chests. 9J.381 96 915 34.519 33 918 32 809 29,419 29.240 21.9 5 30,45i ch>-8t«. 3J.3>8 39 361 4't.l93 41.141 419:^5 41316 31146 :6 989 38,969 Imported for home consumption, in 1850, 7,893,984 pounds; in 1861, 10,073,728 pountis. 1 i !: 1054 4 INDIGO. LAKDix<2a, Dklive&ies, and Stocks of R L iKDiaa In Dec 1861 1850 1849 In 18 months 1851 1850 1849 1848 1847 1846 1846 1844 1843 Ludad. Delivered. Stock 1st Janiuu7, 1869. B«ngal. MfldrM, Total. Home CoDSump- tion. Export. Total. Ben^. Madras, Ac. ToUl. 171 673 22,572 20,057 273 131 9,196 6,802 460 1,404 478 32,363 26,859 32.799 21,623 29.263 28,102 87,461 36.808 22,8U8 619 399 433 8,344 8,551 9,209 10.468 9.010 10,546 10,666 11.664 8,263 1,134 418 1.261 2o,8it1 20,139 23,.S«4 11,095 21.418 11,886 19,302 90.589 14,101 1,813 811 1,694 29.241 28,690 33,773 27,.S63 30,428 28,431 29 968 32,-.! 53 22,954 26,023 23.089 24,989 23,132 24,396 25,333 26,336 22,823 4,304 4116 4,041 6,2.30 7,507 1.845 1,111 3,152 — chests. _ •» u 30.332 " 21.205 " 29 6 " 2>i,962 » 31,902 " ?,3,118 " 33^2 " 25.975 " 21,181 " Indigo from Spanish South America has formed a large feature in our importations of 1851. The landings amount to 7,291 serons, being 4,111 more than the greatest quantity ever before received in one year, and 5,428 more than the average importations of the last ten years. The deliveries have been still greater ; 7,887 serons — equivalent to about 3,900 chests of East Indian production. The parcels, uniformly brought to auction upon arrival, have met with very general attention. The value may be considered relatively as high as Bengal. Tliat such quantities of this indigo were directed to this country is not the result of increased cultivation, but of the high prices current in 1850, offering a better market than those of the United States or the Mediterranean, the usual destination direct from the producing countries- Landings, Delxveries, and Stocks of Spanish Indigo. In December 1851 Tended. Delivered. Stock Ist Jannary. 13 serons 207 serons — serons 1850 316 « 127 " __^ « In 12 months 1851 7,291 " 7,887 * 403 ♦♦ 1850 3,080 " 2,478 * 999 " 1849 2,352 " 3,027 •• 397 " 1848 1,153 " 1,967 • 965 " 1847 2,045 " 1,273 ' 1,779 " 1846 1,265 « 1,414 • 948 " 1845 1,083 " 1,047 ' 1,097 " 1844 1,132 " 1,095 ' 889 " 1843 2,480 " 2,641 ' 891 " 1842 1,968 " 1,850 " 1,062 " INK. 1055 Prices. — Bengal, fine blue, 5*. lOd. to 6«. per lb, ; fine purple and violet, 5a. 2d. to 5«. 9d. ; fine red violet, 5s. Id. to 5s, ^d. ; good purple and violet, 4*. 9>d, to 5s. ; middling violet, 4s. 6c?. to 4». 8d ; middling defective, 4s. to 4s. hd. Consuming, fine, 4s. to 4s. bd. ; middling and good, 3s. 7ct to 3s. llct ; ordinary, 3s. \d. to 3s. 6c?.; ordinary and trash, 2s. Zd. to 2s. lOd. Oude, middling and good, 2s. 6er- nicious combination, productive of a spurious fugitive black, and a liquor corrosive of pens. It is, in fact, a modification of the vile dye of the hatters. Lewis, who made exact experiments on inks, assigned the proportion of 3 parts of galla 1056 INK. to 1 of sulphate of iron, which, with average galls, will answer very well ; but gooa galls will adbules, which must be collected by washing in water, or the application of a magnetic bar. The quantity of iron denotes, of course, the richness of the ore. These assays furnish always a gray cast-iron; and, therefore, the quality of the products can hardly be judged of, except by an experiment on the large scale. The temperature necessary for the success of an assay is about 150° of Wedgewood. In the assays by the humid way, we may expect to find manganese, silica, alumina, lime, magnesia, and sometimes carbonic acid, associated with the iron. 100 grains of the ore in fine powder are to be digested with nitro-muriatic-acid ; which will leave only the silica with perhaps a very little alumina. If an effervescence takes place in the cold with a dilute acid, the loss of weight will indicate the amount of carbonic acid gas ex- pelled. The muriatic solution contains the iron, the manganese, the lime, magnesia, and most of the alumina, with a little silica. On evaporating to dryness, and digesting in water, all the silica will remain in an insoluble state. If the solution somewhat acidu- lated be treated with oxalate of ammonia, the lime will fall down in the form of an ox- alate ; ammonia will now precipitate the alumina and the oxyde of iron together, while the manganese and magnesia will continue dissolved in the state of triple salts (ammonia- muriates). The alumina may be separated from the ferric oxyde by potash-ley. The manganese may be thrown down by hydrosulphuret of potash ; and, finally, the magnesia may be precipitated by carbonate of soda. 100 parts of the red oxyde of iron contain 69-34 of metal, and 30-66 of oxygen. If phosphorus be present in the ore, the nitro-muriatic solution, being rendered nearly neutral, will afford with muriate of lime a precipitate of phosphate of lime, soluble in an excess of muriatic acid. When the sole object is to learn readily the per-centage of iron, the ore maybe treated with hot nitro-muriatic, the acid solution filtered and supersaturated with ammonia, which will throw down only the iron oxyde and alumina ; because the lime is not pre- cipitable by that alkali, nor is magnesia and manganese, when in the state of ammonia- 1066 mojN. muriates. The red y»recipitate, being digested with some potash-ley, will lose its alumina and will leave the ferric oxyde nearly pure. The presence of sulphur, pliosphorjs, oi arsenic, in iron ores, may always be detected by the blowpipe, or ustulation in the as^ay muffle, as described under Furnace. Of the smelting of iron ores. — We sRall describe, in the first place, the methods prac- tised in Great Britain, and shall afterwards consider those pursued in other countries, in the treatment of their peculiar ores. Iron is divided into three kinds, according to the different metallic states in which it may be obtained ; and these are called crude or cast iron; steel; and bar or mal!eable iron. These states are determined essentially by the different proportions of charcoal or carbon held in chemical combination ; cast iron containing more ihan steel, and steel more than malleable iron ; which last, indeed, ought to be the pure metal, a point of perfec- tion, however, rarely if ever attained. It is impossible to assign the limits between these three forms of iron, or their relative proportions of carbon, with ultimate precision ; for bar iron passes into steel by insensible gradations, and steel and cast iron make such mutual transitions as to render it difficult to define where the former commences, and the latter ceases, to exist. In fact, some steels may be called crude iron, and some cast irons may be reckoned among steels. Towards the conclusion of the last century the manufacture of iron underwent a very important revolution in Great Britain, by the substitution of pitcoal for charcoal of wood, the only combustible previously used in smelting the ores of this metal. This improvement served not merely to diminish the cost of reduction, but it furnished a softer cast iron, fit for many new purposes in the arts. From this era, iron works have assumed an immense importance in our national industry, and have given birth to many ingenious and powerful machines for fashioning the metal into bars of every form, with almost incredible economy and expedition. The profusion of excellent coal, and its association in many localities with iron-stone, have procured hitherto for our country a marked superiority over all others in the iron trade ; though now every possible effort is making by foreign policy to rival or to limit our future operations. In 1802, M. de Bonnard, now divisionary inspector in the royal corps of mines of France, and secretary of the general council, made a tour in England, in order to study our new processes of manufacturing iron, and published, on his return, in the Journal des Mines, tom. 17, a memoir descriptive of them. Since the peace, many French engineers and iron-masters have exerted themselves in naturalizing in France this species of industry ; and M. de Gallois, in particular, after a long residence in Great Britain, where he was admitted to see deliberately and minutely every department of th< iron trade, returned with ample details, and erected at Saint-Etienne a lars^e establish- ment entirely on the English model. More recently, MM. Dufrenoy and Elie de Beau- mont, and MM. Coste and Perdonnet, have published two very copious accounts of their respective metallurgic tours in Great Britain, illustrated with plans and sections of our furnaces, for the instruction of the French nation. The argillaceous carbonate of iron, or clay iron-stone of the coal measures, is the chief ore smelted in England. Some red hematite is used as an auxiliary in certain works in Cumberland and Lancashire ; but nowhere is the iron-sand, or other ferruginous matters of the secondary strata, employed at present for procuring the metal. Among the numerous coal-basins of England there are two, in particular, which fur- nish more than three fourths of the whole cast iron produced in the kingdom ; namely, the coal field of Dudley, in the south of Staffordshire ; and the coal fields of Monmouth- shire, in South Wales, along with those of Gloucestershire and Somersetshire. Dudley is peculiarly favored by nature. There are found associated the coal, the iron ore, the limestone for flux, and the refractory fire-clay for constructing the interior brick-work of the furnaces. This famous clay is mined at Stourbridge, and exported to every part of the kingdom for making cast steel crucibles and glass-house melting pots. At Merthyr-Tydvil, the centre of the iron-works of Wales, the iron-stone is extremely plentiful, forming 16 beds, or rather constituting an integrant portion of 16 beds of slate-clay. Sometimes it occurs in pretty long tables adjoining each other, so as to resemble a continuous stratum; but more frequently it forms nodules of various size and abundance, placed in planes both above and below the coal seam. Eight varieties of ore, belonsins: to different beds, have been distinguished by the following barbarous names : black balls, black pins, six-inch-wide vein, six-inch jack, blue vein, blue pins, gray pins, seven pins. The bed containing the first quality of iron-stone is analogous to the black ore of Staffordshire, called gubbin; it is often cleft within like sept aria, and its cavities are sometimes besprinkled with crystals of carbonate of lime or quartz. In the superior beds there are nodules decomposing into concentric coats, of which the middle is clay. Crystals of oxyde of titanium are occasionally found in the middle of IRON. 1067 the balls of clay iron-stone ; to which the metallic titanium observed in the inside of the dome of blast furnaces, may be traced. Both at Dudley and South Wales, casts of shells, belonging to the genus uniOj are observed on the iron-stone. The average richness of the iron-stones of South Wales is somewhat greater than that o^ those of Staffordshire. The former is estimated at 33 parts of cast iron, while the latter rarely exceeds 30 parts in 100 of ore ; and this richness, joined to the superior quality or cheapness of the coals, and the proximity of the sea, gives South Wales a decided advan- tage as a manufacturing district. The number of blast furnaces in the parish of Merthyr-Tydvil amounts to upwards of 30. The cast iron produced is, however, seldom brought into the market, but is almost entirely converted into bar iron, of which, at Mr. Crawshay's works, 600 tons are manu- factured in a week. Numerous iron railways, extending through a length of 220 miles, facilitate the transport of the materials and the exportation of the products. That con- currence of favorable circumstances, which we have noticed as occurring at Dudley, pre- vails in an equal degree in South Wales. The same economy which the use of coal has introduced into the smelting of cast iron from the ore, also extends to its refinery into bars. And this process would supersede in every iron work the use of wood charcoal, were not the iron produced by the latter com- bustible better for many purposes, particularly the manufacture of steel. In some English smelting works, indeed, where sheet iron is prepared for making tin plate, a mixed refining process is employed, where the c^t iron is made into bar iron by wood charcoal, and xaminaied by the aid of a coal fire. Till 1740, the smelting of iron ores in England was executed entirely with wood char- coal ; and the ores employed were principally brown and red hematites. Earthy iron ores were also smelted ; but it does not appear that the clay iron-stones of the coal-basins were then used, though they constitute almost the sole smelting material at the present day. At that era, there were 59 blast furnaces, whose annual product was 17,350 tons of cast iron ; that is, for each furnace, 294 tons per annum, and 5| tons per week. By the year 1788, several attempts had been made to reduce iron ore with coked coal ; and there re«iained only 24 charcoal blast furnaces, which produced altogether 13,000 tons of cast iron in the year; being at the rate of 546 tons for each per annum, or nearly 11 tons per week. This remarkable increase of 11 tons for 5|, was due chiefly to the sub- stitution of cylinder blowing machines worked with pistons, for the common wooden bellows. Already 53 blast furnaces fired with coke were in activity ; which furnished in toto 48,800 tons of iron in a year ; which raises the annual product of each furnace to 907 tons, and the weekly product to about 17| tons. The quantity of cast iron produced that year (1788) by means of coal, was ----__ 48,800 tons, and that by wood charcoal, was - - - - . - 13,100 Constituting a total quantity of -...-. 61,900 tons. In 1796, the wood charcoal process was almost entirely given up; when the returns of the iron trade made by desire of Mr. Pitt, for establishing taxes on the manufacture afforded the following results: — 121 blast furnaces, furnishing in whole per annum 124,879 tons, constituting an average amount for each furnace of 1032 tons. In 1802, Great Britain possessed 168 blast furnaces, yielding a product of about 170,000 tons; and this product amounted, in 1806, to 250,000 tons, derived from 227 coke fur- naces, of which only 159 were in activity at once. These blast furnaces were distributed ai follows. In the principality of Wales --------52 In Staffordshire -----..-...42 In Shropshire ---------..42 In Derbyshire ----.----..17 In Yorkshire -...28 In the counties of Gloucester, Monmouth, Leicester, Lancaster, Cumber- land, and Northumberland ---...._ ]8 In Scotland ------.....28 227 In .820, ihe iron trade had risen to the amount shown in the following table: — Tons. Wales manufactured, per annum ------- Shropshire and Staffordshire ----... Yorksliire and Derbyshire ---..-.- Scotland, with some places in England ....-- 150,000 180,000 50,000 20,000 Total 400 000 1068 IRON. IRON. 1069 In a statistical view given by M. de Villefosse, of the French and English iron works, be assigns to the latter, in 1826, 305 blast furnaces, distributed as follows : — In the principality of Wales --------87 In Stafi'ordshire -----------78 In Shropshire, Derbyshire, Yorkshire, &c. ----- 84 In Scotland .----------56 305 Out of these, 280 were in activity at the same time; and if we suppose their mean product to have been 50 tons a week, the total product would have been, in 1826, 728,000 tons. But this estimate seems to be somewhat above the truth ; for, from the information communicated by Mr. Philip Taylor to M. Achille Chaper, a considerable French iron- master, who, in the summer of 1826, inspected two thirds of the blast furnaces of Great Britain, their product during this year was about 600,000 tons. The preceding details show the successive increments which the manufacture of cast iron has received ; and a similar progression has taken place in its refinery- into wrought iron. This operation was formerly effected by the agency of wood charcoal in refineries analogous to those still made use of in France. But when that kind of fuel began to be scarce in this island, it came to be mixed with coke in various proportions. The bar iron thus produced was usually hard, and required much time to convert, so that an establish- ment which could produce 20 tons of bar iron in a week, was deemed considerable. At that time, England imported annually from Sweden and Russia the enormous quantity of 70,000 tons of iron. Mr. Cort, to whom Great Britain is indebted for the methods now pursued in this country, succeeded about that time, after many unsuccessful experiments, in converting cast iron into bar iron, by exposing it on the hearth of a reverberatory furnace to the flame of pitcoal. This method, which possessed the advantage of employing this species of com- bustible alone, likewise simplified the treatment, because it required no blast apparatus. But this mode of refinery, consisting in the use of a reverberatory furnace alone, did not produce altogether the desired result. It was irregular; sometimes the loss of iron was small, but at others it was very considerable ; and there were great variations in the quality of the iron, as well as in the quantity of fuel consumed. Mr. Cort succeeded in removing this uncertainty of result, by causing the puddling in the reverberatory furnace to be preceded by a kind of refinery with coke. The intent of this operation was to de- carburate the iron, and to prepare it for becoming malleable. The metal took in that case the name of finery metal, called, for the sake of brevity, fine-metal. He also substituted the drawing cylinders for the extension under the hammer, an im- provement which accelerated greatly the manufacture of bar iron. The iron then yielded by the operation of puddling was of a very inferior quality, and could not be directly em- ployed in the arts. In order to give it more consistence, it was subjected to a second heating in a reverberatory furnace ; and whenever this method had arrived at a high enough de- gree of perfectioir to afford products fit for the market, it became exclusively employed in Great Britain. This new method of transforming cast iron into malleable iron speedily gained such an extension, that of late years, a single iron-work, Cyfartha in Wales, man- ufactured annually more than twice as much as was made annually from 1740 to 1750, in the whole kingdom. In surveying the improvements which the iron manufacture has received in England in the space of the last 60 years, they are seen to be resolvable into two ; the first set re- lating to the smelting of flie ores ; the other, to the conversion of the pigs into bar iron j hence naturally arise two heads under which the subject of iron must be treated. 1. Manufaciure of cast-iron by coke and coal. — The cast-iron produced by the English and Scotch blast furnaces is in general black and very soft ; but yet may be distinguished into several qualities, of which three are particularly noticed. No. 1. Very black casMVon, in large rounded grains, obtained commonly near the com- mencement of the casting, when an excess of carbon is present ; in flowing, it appears pasty, and throws out blue scintillations. It exhibits a surface where crystalline vegeta- tions develop themselves rapidly in very fine branches; it congeals or fixes very slowly; its surface when cold is smooth, concave, and often charged with plumbago ; it has but a moderate tenacity, is tender under the file, and susceptible of a dull polish. When melted ovei again, it passes into No. 2, and forms the best castings. No. 2. Black cast-iron has a somewhat lighter shade than the preceding, and may ther**fore on comparison be called blackish-gray. It presents less large granulations than No. 1 ; is tenacious, easily turned, filed, and polished ; excellent for casting when it ap- proaches to No. 1, and for the manufacture of bar iron when it has on the contrary a i shade somewhat lighter. If repeatedly melted, it passes into the next quality, or No. 3. White cast iron; this is brittle, and indicates always some derangement in thi» working of the furnace; it flows imperfectly, and darts out, in casting, abundance of brilliant white scintillations; it fixes very quickly ; and on cooling, exhibits on its surface irregular asperities, which make it extremely rough. It is easily broken, and presents s lamellar and radiated fracture ; and is so hard that tempered steel cannot act upon ii. It is cast only into weights, bullets, or bombs, but never into pieces of machmery. When exposed to the refinery processes, it affords a bad bar iron. It is owing probably to the different nature of the cast iron obtained in different counties in England, that Staflord- shire and Shropshire furnish the greater part of the great iron castings, while Wa es manufactures almost exclusively malleable iron. The lower price of coals m Wales is perhaps the cause to a certain extent of this difference in the results of these two iron districts. It will be interesting, at any rate, to describe separately the processes employed in Staffoidshire and Wales. , ^ ^ ,, t.i a The blast furnaces of Staffordshire^ in the neighborhood of Dudley, Bilston, and Wednesbury, are constructed almost wholly of bricks. Their outer form is frequently a cone, often also a pyramid with a square base. They are bonnd about with a great many iron hoops, or with iron bars placed at different heightz. This powerful armor allows the furnaces to be built much less massively than they formerly were ; and admits lighter and more elegant external forms. They are seldom insulated ; but are usually associated to the number of two or three in the same line. A narrow passage is left between them, which leads to the lateral openings where the tuyeres are placed. At the front of the furnace, a large shed is always raised. The roofs of these sheds present in general circular profiles, and being made of cast or bar iron, they display a remarkable lightness of construction. The cast iron columns likewise, which support the joists and girders, give additional elegance. In the Dudley field, the furnaces are almost always in the middle of the plain, and an inclined rail-way must be formed to reach their platform. These inclined planes, com- posed of beams or rails placed alongside of each other, and sustained by props and cross- bars, as indicated in fig. 793, are set up mostly against the posterior face of the furnace. Two' chains or ropes, passmg over the drums of gins, moved by a steam engine (commonly the same that drives the bellows), draw up the wagons of wood or sheet iron a o, which contain the various materials for supplying the furnace. To facilitate this service, the platform round the furnace is sometimes enlarged behind by a floor ; while a balustrade, which opens when the wagons arrive at the platform, prevents accidents. This pro- jection is occasionally covered by a roof. For a furnace of the largest size, the force ex- pc:nded by this lifting apparatus is not more than a two-horse power. Fig. 793 is a vertical section through the furnace from front to rear, or at right angles to the line of the lateral tuyeres. The erection of a pair of blast furnaces, of 40 feet high each, costs, in the Dudley district, 1800 pounds sterling ; and requires for building each, 160,000 common bricks for the outside work, 3900 fire-bricks for the lining or shirt of the furnace, and 825 for the boshes. The dimensions of the fire-bricks are various; 5 kinds are emidoyed for the lining, and 9 kinds for the boshes. They are all 6 inches thick, and are curved to suit the voussoirs. The number of charges given in 12 hours is different in different furnaces ; being sometimes 20, 25, and even so high as 40; but ^0 is a fair average. Each charge is IRON. 1071 1070 iROW. composed of from 5 to 6 cwts. of coke, (or now of 3 to 4 cwts. of coal with the hot blast) j 3, 4 and sometimes 6 cwts. of the roasted mine, according to its richness and the quality of cast iron wanted; the limestone flux is usually one third of the weight of the roasted iron stone. There are 2 casts in 24 hours ; one at 6 in the morning, and another at 6 in the evenin". The height of the blast furnaces is veiy variable; some being only 36 feet high including the chimney, while others have an elevation of 60 feet. These extreme limits are very rare : so that the greater part of the furnaces are from 45 to 50 feet high. They are all terminated by a cylindrical chimney of from 8 to 12 feet long; being about one fifth of the total height of the furnace. The inside diameter of this chimney is the same as that of the throat or mouth ; and varies from 4 to 6 feet. The chimney is fre- quently formed of a single course of bricks, and acquires solidity from its hoops of iron, so thickly placed that one half of the surface is often covered with them. At its lower end, the mouth presents one or two rectangular openings, through which the charge is ?iven. It is built on a basement circle of casi-iron, which forms the circumference of the throat ; and a sloping plate of cast-iron 6 is so placed as to make the materials slide ov-r into the furnace, as shown in the figure. The insiie of the blast furnaces of Staffordshire is most frequently of a circular form, except the hearth and working area. The inner space is divided into four portions, different in their forms, and the functions which they fulfil in the smelling of the ore. The undermost, called the hearth, or crucible, in which the cast-iron collects, is a right rectangular prism, elongated in a line prependicular to the axes of the tuyeres. The 5ides of the hearth consist in general of refractory sandstone (fire-stone), obtained mostly "rom the bed of the coal basin, called millstone grit ; and the bottom of the hearth is form- 2d of a large block of the same nature, laid on a cast-iron plate. The second portion is also made of the same refractory grit stone. It has the form of quadrangular pyramidal, approaching considerably to a prism, from the smallness of the ingle included between the sides and the aj^s. The third portion or lower body of the furnace is conical, but here the interior space suddenly expands ; the slope outwards at this part seems to have a great influence on the quality of the cast-iron obtained from the furnace. When No. 2 of the blackest kind is wanted for castings, the inclination of this cavity of the furnace is in general less considerable than when No. 2 cast iron for conversion into bar iron is required. The inclination of this conical chamber, called the boshes, varies from 55 to 60 degrees with the iorizon. The diameter of this part is equal to that of the belly, and is from 11 to 13 feet. The boshes are built of masonry, as shown in Jigs, 794, 795. 794 The fourth part, which constitutes about two thirds of the height of the furnace from the base of the hearth up to the throat, presents the figure of a surface of revolution, generated by a curve whose concavity is turned towards the axis of the furnace, and Those last tangent towards the bottom is almost vertical. This surface is sloped off with that of the boslies (etalages in French), so that no sharp angle may exist at the belly. In some furnaces of considerable dimensions, as in that with three tuyeres, this portion of the furnace is cylindrical for a certain height. The following measurements represent the interior structure of two well-going farnaees. Height from the hearth to the throat or mouth Height of the crucible or hearth — of the boshes _ - - — of the cone . - - ■ — of the chimney or mouth - Width of the bottom of the hearth Ditto at its upper end . - - Ditto of the boshes . - - Ditto at one third of the belly Ditto at two thirds of ditto Ditto at the mouth _ - - Inclination of the boshes - * No. 1. No. 2. Feet. 45 6i 8 30^ 8 3 12f 12 8f 4| 59° Feet. 49 6 7 36 12| 2 2f 13i Uh 9k 3f 52° The conical orifice called the tuydre, in which ihe tapered pipes are placed, for impart ing the blast, is seen near the bottom of the furnace, yjg. 794, at a. Nose tubes of va- rious sizes, from 2 to 4 inches in diameter, are applied to the extremity of the main blast-pipe. Under a is the bottom of the hearth, which, in large furnaces, may be two feet square, b is the top of the hearth, about two feet six inches square, a b is the height of the hearth, about six feet six inches, b shows the round bottom of the conical or funnel part, called in this country the boshes, standing upon the square area of the hearth c is the top of the boshes, which may b6 about 12 feet in diameter, and 8 leet in perpendicular height, d is the furnace top or mouth {gueulard in French), at which ihe materials are charged. It may be 4^ feet in diameter. The line between c, d is the hei«'ht of the internal cavity of the furnace, from the top of the boshes upwards, sup- •posed to be 30 feet, a, d, is the total height of the interior of the furnace, reckoned at 44i feet e e is the lining, which is built in the nicest manner with the best fire- bricks, from 12 to 14 inches long, 3 inches thick, and curved to suit the circle of the cone. A vacancy of 3 inches wide is lefl all round the outside of the first lining by the builder; which is sometimes filled with coke dust, but more generally with sand firmly rammed. This void space in the brick -work is for the purpose of allowing for any expansion which mieht occur, either by an increase in the bulk of the building, or by the pressure and weight of the materials when descending to the bottom of the furnace. Exterior to e e is a second lining of fire-bricks similar to the first. At f, on either side, is a cast-iron lintel 8i feet long, by 10 inches square, upon which the bottom of the arches is sup- ported. %, G, is the rise of the tuyere arch, which may be 14 feet high upon the outside, and 18 feet wide. The extreme size of the bottom or sole of the hearth, upon each side of A, may be 10 feet square. This part and the boshing stones are preferably made from a coarse sandstone grit, containing large rounded grains of quartz, united by a sili- ceo-argillaceous cement. • , .. » v .v The" bottom of the hearth consists, first, of a course of the said gritstone ; beneath which is a layer of bedding sand, having, in its under part, passages for the escape of the vapors generated by damps; the whole being supported upon pillars of brick. Fig. 795 represents the hearth and boshes, m a vertical side section, a is the lymp stone, and b the tymp plate for confining the liquid metal in the hearth. The latter is wedged firmly into the side- walls of the hearth; c is the dam-stone, which occupies the whole breadth at the bottom of the hearth, excepting about 6 inches, which space, when the furnace is at work, is filled, before every cast, with a strong binding sand. This stone is faced outside by a cast-iron plate d, called the dam-plate, of considerable thickness, and peculiar shape. The top of the dam-stone, or rather the notch ,, of the dam-plate, lies from 4 to 8 inches under the level of the tuyere hole. The space under the tymp plate, for 5 or 6 inches down is rammed full, for every cast, with strong loamy earth, or even fine clay ; a process called tTTymp stopping. The area of the base of this furnace being 38 feet, its extreme **^The blast tVimaces of Staffordshire have always two tuyeres, at least, placed on opp<> I 1072 IRON. IRON. 1073 «ite sides, but so pointed that the blast may not pursue directly opposite lines. In a furnace acting well in the neighborhood of Dudley, the one of the tuyeres was 10 inches distant from the posterior wall of the hearth, and the other only four inches. In other furnaces with 3 tuyeres, the side ones are placed, the one 16| inches, and the other 6| inches from the back. Three tuyeres are seldom made to blow simultaneously. The third is brought into action only when the furnace seems to be choked up, and when it becomes necessary to clear it up by a powerful concussion. Too much pains cannot be bestowed on the masonry and brickwork of a blast furnace, and on the solidity of its foundation. In a soft ground it should rest on piles, so driven that the channel left beneath for the drainage of the building may be above any water level. Small passages should likewise be left throughout the body of the work, for the transpiration of moisture. The blowing machines employed in Staffordshire are generally cast-iron cylinders, in which a metallic piston is exactly filled as for a steam engine, and made in the same way. Towards the top and bottom of the blowing cylinders orifices are left covered with valves, which open inside when the vacuum is made with the cylinders, and after- wards shut by their own weight. Adjutages conduct into the iron globe or chest, the air expelled by the piston, both in its ascent and descent ; because these blowing machines have always a double stroke. The pressure of the air is made to vary through a very considerable range, according to the nature of the fuel and season of the year ; for as in summer the atmosphere is more rarefied, it must be expelled with a compensating force. The limits are from Ij pounds to 3 1 pounds on the inch; but these numbers represent extreme profKirtions, the average amount in Staffordshire being 3 pounds. With this pressure a furnace usually works, which affords 60 tons of cast-iron in the week ; and the pressure may be 2J pounds on an average. The orifices, or nose-pipes, through which the air issues, also vary with the nature of the coke and the ore. In Stafibrdshire they are generally from 2 inches and 5 tenths to 2 inches and 8 tenths in diameter. The blowing machines of Slaffordshire are always impelled by steam engines. At Mr. Bagnall's works, two blast furnaces, 40 feef high, exclusive of the chimney or top, and two finery furnaces, are worked by a steam engine of 40 horses power ; and therefore the power of one horse corresponds to the production of 2^ tons of cast iron per week, independently of the finery. In South Wales, especially at Ponlypool, there are slighter blast furnaces, whose upper portion is composed of a single range of bricks, each cf which is 20 inches long, 4 thick, and 9 broad. The interior of the chimney represents an inverted cone. These furnaces derive solidity, and power to resist the expansions and contractions from change of tem- perature, by being cased, as it were, in horizontal hoops, placed 3 feet, or, even in some cases, only 6 inches asunder. These flat rings consist of four pieces, which are joined by means of vertical bars, that carry a species of ears or rings, into which the hoops enter^ and are retained by bolts or keys. Instead of these ears, screw nuts are also employed for the junction. Each hoop is alternately connected to each of the eight vertical bars. The interior of these furnaces is the same as of the others ; being generally from 12 to 14 feet diameter at the belly, and from 50 to 55 feet high. Though slight, they last as long as those composed of an outer body of masonry and a double lining of bricks; and have continued constantly at work for three years. In Wales also the blast furnaces are generally somewhat larger than in Staffordshire ; because there the object being to refine the cast iron, they wish to procure as large a smelting product as possible. But in Staf- fordshire, a fine quality of casting iron is chiefly sought after, and hence their furnaces have less height, but nearly the same width. In a blast apparatus employed at the Cyfartha works, moved by a 90 horse steam power, the piston rod of the blowing cylinder is connected by a parallelogram mechanism with the opposite end of the working beam of the steam engine. The cylinder is 9 feet 4 inches diameter, and 8 feet 4 inches high. The piston has a stroke 8 feet long, and it rises 13 times in the minute. By calculating the sum of the spaces percurred by Ihe piston in a minute, and supposing that the volume of the air expelled is equal to only 96 per cent, of that sum, which must be admitted to hold with machines executed with so much precision, we find that 12,588 cubic feet of air are propelled every minute. Hence a horse power applied to blowing machines of ihis nature gives, on an average, 137 cu- bic feel of air per minute. The pressure on the air, as it issues, rarely exceeds two pounds on the square inch in the Welsh works. At the establishment of Cyfartha, for blowing seven smelting furnaces, and the seven corresponding fineries, three steam engines are employed, one of 90 horse power, another of 80, and a third of 40 ; which constitutes in the whole a force of 210 horses, or 26 horses and l per funiacCy supposing the fineries to consume one eighth of the blast. In the whole of the works of Messrs. Crawshay, the proprietors of Cyfartha, the power of about 350 horses is expended in blowing 12 smelting furnaces, and their subordinate fineries ; which gives from 25 to 26 horses for each, allowing as before one eighth for the fineries. As *hese furnaces produce each about 60 tons of cast iron weekly, we find ihat a horse power corresponds to 2 tons and a tenth in that time. Each of the furnaces consumes about 3567 cubic feet of air per minute. These works have been greatly increased of late years. The following analyses of the English coal ironstones have been made by M. Berthier, at the school of mines in Paris. \ Loss by ignition - Insoluble residuum Lime - - - Peroxyde of iron - Rich Welsh Ore. 30-00 8-40 0-0 60-00 Poor Welsh Ore. I 2700 22-03 600 42-66 Rich Ore of Dudley, i or gubbin. 21 00 7-66 2-66 58-33 On calculating the quantities of carbonate of iron, and metallic iron, to which above peroxyde corresponds, we have : — the ' Carbonate of iron Metallic iron 88-77 42-15 65-09 31-38 85-20 40-45 The mean richness of the ores of carbonate of iron of these coal basins is not far from 33 per cent. About 28 per cent, is dissipated on an average, in the roasting of the ores. Eveiy ferruginous clay-stone is regarded as an iron ore, when it contains more than 20 per cent, of metal ; and it is paid for according to its quality, being on an average at 12 shillings per ton in Staffordshire. The gubbin, however, fetches so high a price as 16 tx ^7 shillings. The ore must be roasted before it is fit for the blast furnace, a process cauied on in the open air. A heap of ore mingled with small coal (if necessary) is piled up over a stratum of larger pieces of coal; and this heap may be 6 or 7 feet high, by 15 or 20 broad. The fire is applied at the windward end, and after it has burned a certain way, the heap is prolonged at the other extremity, as far as the nature of the ground or convenience of the work requires. The quantity of coal requisite for roasting the ore varies from one to four hundred weight per ton, according to the proportion of bituminous matter associated with the iron-stone. The ore loses in this operation from 25 to 30 per cent, of its weight. Three and a quarter tons of crude ore, or two and a quarter tons of roasted ore, are required to produce a ton of cast-iron ; that is to say, the crude material yields on an average 30-7 per cent., and the roasted ore 44-4 of pig metal. In most smelting works in Staffordshire, about equal weights of the rich ore in round nodules called gtlk>m, and the poorer ore in cakes called blue fiat, are employed together in their roasted state ; but the proportions are varied, in order to have a uniform mix- ture, capable of yielding from 30 to 33 per cent, of metal. The transition or carboniferous limestone of Dudley is used as the flux ; it is compact and contains little clay. The bulk of the flux is made nearly equal to that of the ore. To treat two tons and a quarter of roasted ore, which furnish one ton of pig iron, 19 hundred weight of limestone are employed ; constituting nearly 1 of limestone for 3 of unroasted ore. The limestone costs 6 shillings the ton. Carbonized pitcoal or coke was, till within these few years, the sole combustible used in the blast furnaces of Slaflfordshire. The coal is distributed in circular heaps, about 5 feet diameter, by 4 feet high ; and the middle is occupied by alow brick chimney, piled with loose bricks, so open as to leave interstices between them, especially near the ground. The larger lumps of coal are arranged round this chimney, and the smaller towards the circumference of the heap. When every thing is adjusted, a kindling of coals is introduced into the lx4toro of the brick chimney ; and to render the combustion slow, the whole is covered over with a coat of coal dross, the chimney being loosely closed with a slab of any kind. Openings are occasionally made in the crust and afterwards shut up, to quicken and retard the ignition at pleasure, during its continuance of 24 hours. Whenever the carbonization has reached the proper point for forming good coke, the covering of coal dross is removed, and water is thrown on the heap to extinguish the combustion ; a circumstance deemed useful to the quality of the coke. In this operation the Staffordshire coal loses the half of its weight, or two tons of coal produce one of coke. As soon as the blast furnace gets into a regular heat, which happens about 15 days or three weeks after fires have been put in it, the working consists simply in charging it, at the opening in the throat, whenever there is a sufficient empty space; the only rule being to keep the furnace always full. The coke is measured in a basket, thirteen of which go to the ton. The ore and the flux (limestone) are brought forwards in wheel- barrows of sheet iron. In 24 hours, there are thrown into a furnace such as y/g. 582, 14| tons of coke, 16 tons of roasted ore, and 6f tons of limestone; from which about 7 tons of pig iron are procured. This is run ofl' every 12 hours; in some works the blast is suspended during the discharge. The metal intended to be converted into •/I 1074 IRON. bar iron, or to be cast again into moulds, is ran into small pigs 3 feet long, and 4 inches diameter : weighing each about 2 hundred weight and a half. The disorders to which blast furnaces are liable have a tendency always to produce while cast-iron. The color of the slag or scoriae is the surest test of these derange- ments, as it indicates the quality of the product.. If the furnace is y/^lding an iron nrone^ for casting into moulds, the slag has a uniform vitrification, and is slishtly trans- lucid When the dose of ore is increased in order to obtain a gray pig iron, fat lor fabrication into bars, the slag is opaque, dull, and of a greenish-yellow tint, with blue enamelled zones. Lastly, when the furnace is producing a white metal, the slags are black, glassy, full of bubbles, and emit an odor of sulphureted hydrogen. The scoriSB from k coke are much more loaded with lime than those from a charcoal blast furnace. This excess of lime appears adapted to absorb and carry off the sulphur, which would otherwise injure the quality of the iron. The slags, when breathed on, emit an argiUa- *^T blast furnace of 50 or 60 feet in height gives commonly from 60 to 70 tons of cast- iron per week; one from 50 to 55 feet high, gives 60 tons ; two united of 4o feet produce together 100 tons ; and one of 36 feet furnishes from 30 to 40. A blast furnace should go for four or five years without needing restoration. From 31 to 4 tons of coal, inclu- sive of the coal of calcination, are required in Staffordshire to obtain one ton of cast-iron; and the expense in workmen's wages is about 15 shillings on that quantity. At the Cyfartha works of Messrs. Crawshay in South Wales, the average price of the lithoid carbonate of iron, ready for roasting, is only 7^. 6d. a ton, and its richness is about 33 per cent. The furnaces for roasting the ore in that country are made in the lorm ol cylinders, placed above an inverted cone. The cylindrical part is 6 feet high and wide, and the cone is about 4 feet high, with a base equal to that of the cylinder; towards the bottom or narrowest part of the inverted cone, there is an aperture which terminates in an outlet on a level with the bottom of the terrace in which the furnace is built. Sometimes, however, all the roasting furnaces are in a manner combined into one, which resembles a long pit about 6 feet in width and depth, and whose botiom presents a series of inverted hollow quadrangular pyramids, 6 feet in each side, and 4 deep, ine bottom or apex of each of these pyramids communicates with a mouth or door-way that opens on a lower terrace, through which the ore falls in proportion as it is roasted ; and whence it is wheeled and tumbled into the throat of an adjoining blast furnace, on the same level with the terrace; for in Wales the blast furnace is generally built up against the face of a hill, which makes one of its fronts. The above roasting fur- naces, which closely resemble lime-kilns, after being filled with alternate strata of small coal and ore, are set on fire; and the roasted ore is progressively withdrawn below, as already mentioned. • -117 i ♦v-.. :« c»«r The product of coke from a certain weight of coal is greater m Wales than in btal- fordshire, though the mode of manufacture is the same. At Pen-y-Darran, for example, 5 of coal furnish 3| of coke; or 100 give 70 ; at Dowlais 100 of coal afford 71 of coke, and the product would be still greater if more pains were bestowed upon the Process. At Dowlais, coal costs only 2 shillings a ton ; at Cyfartha, it is worth from 25. 6d. to 5 shillings. About 2 tons of coke are employed in obtaining 1 ton of cast-iron. According to M. Berthier's analysis, the slag or cinder of Dowlais consists of silica, 40-4; lime;38-4; magnesia, 5-2; alumina, 11-2; protoxyde of iron, 3-8 ; and a trace of sulphur. He says that the silica contains as much oxygen as all the other bases united ; or is equivalent to them in saturating power ; and to the excess of hme he ascribes the freedom from sulphur, and the good quality of the iron produced. The specimen exam- ined was from a furnace at Merthyr-Tydvil. Other slags from the same furnace, and one from Dudley, furnished upwards of 2 per cent, of manganese. Those which he analyzed from Saint Etienne, in France, afforded about 1 per cent, of sulphur. The consumption of coal in the Welsh smelting furnaces may be estimated, on an average, at 3 Ions per ton of cast-iron ; corresponding to 2-1 of their coke, from this economy in the quantity of fuel, as well as from its cheapness and that of the iron ore, the iron of South Wales can be brought into the market at a much lower rate than that of any other district. These blast furnaces remain in action from 5 to 10 years ; at the end of which time, only their interior surface has to be repaired. The lining of the upper part lasts much longer; for examples are not wanting of its holding good tor nearly 40 years. . r . • One of the greatest improvements ever made by simple means m any manufacture is the employment of hot air, instead of the ordinary cold air of the atmosphere, in supply- in** the blast of furnaces for smelting and founding iron. The discovery of the supe- rior power of a hot over a cold blast in fusing refractory lumps of cast-iron was acci- dentallv observed by my pupil, Mr. James Beaumont Neilson, engineer to the Glasgow gas wo'rks, about the year 1827, at a smith's forge in that city, and it was made the subject of a patent in the month of September of the following year. No particular construction of apparatus was described by the inventor by which the a'x was to be IRON. 1075 heaed,and conveyed to the furnace; but it was merely staled that the air may be heated in a chamber or closed vessel, having a fire under it, or in a vessel connect«l S any convenient manner with the forge or furnace. From this ve«el thrair is to be forr^H by means of bellows info the furnace. The quantity of surfaev^i ha hea in <> fur nte^ JXt che^%t '/"''f' '' '^"' '^? ""^i*^ 'l'""'' ' ^'' ^ ^"P«^^ furnace, about "(^ cubic inches. The vessel may be enclosed in brickwork, or fixed in any other mainer that may be found desirable, the application of heated air in «y way ^o furnaces S Wherever a forced stream of air is employed for combustion, the resulting temperature must evidently be impaired by the coldness of the air injected upon theS The heH developed in combustion is distributed into three portions ; one is commri'cated to the fatTirn"!.^"^'' T'^:i '' .^^""^^"i^^ted to the azote of the atm^eTeTand to the v^ ^tile products of coirfbustion, and a third to the iron and fluxes, ir other .urroundi^^ nW -n' \^^''''^^'^' dissipated by wider diffusion. This inevi\ableXributLn taief place in such a way, that there is a nearly equal temperature over the whole extent of a fire-place, m which an equal degree of combustion exists. We thus perceive that if the air and the coal be very cold, the portions of hp«» «K- sorbed by them might be very considerable, and sufficient TpVeveiL^the re.ultf^^^^ peraturefrom rising to a proper pitch; but if they were veryTo^.^ey wrulHbsort ess caloric, and won d leave more to elevate the common temperature L^ us sup ^sc tTeo^h r^ chargea with burning fuel, into one of which cold air is blown, and S the other hot air m the same quantity. In the same time, nearly equal quanth es of fud ^^'re wm"'T>f^ T'^ ^ ""5''^y "^"^^ production of heat ; but notlithS n ' of this there will not be the same degree of heat in the two fu;naces, for the one which re' ceives the hot air will be hotter by all the excess of heat in its air above that of the" we to STa'ine th'Tr •"•' ?''' V'f '^^^ "^"^ ^^^ >^«^^ ^^^^-^»« ?rom it Nor ^l we to imagine that by injecting a little more cold air into the one furnace, we can raise ^heTme ti^JV';'/ T l^" . '^'''' "^''^ ^^^ ^"^-^^ ^^ should bur^ more co^ in the same time, and we should produce a greater quantity of heat, but this heat being diffused proportionally among more considerable masses of matter! w^ld not produce I oTh^ iLThrslTsUTe/'""^^ ^^^^ ^ '-^- ^^- ^-^^d' ^"^ -t a g're'ltlr^lntn^tj fir^f^' w^i^h^W^V I'lf t^'^'fu P"'"''P^^' f '^^ production and distribution of heat, fires fed with hot air should, with the same fuel, rise to a higher pitch of temperature ie^g Iftfuefra "Z7^ '''' ^\ 7''^ consequence is independent of th^mate^ or-frcT^^^^ Si TZZ^^ ^^ ;- 0^? tr^:lu^e prXS b^ This principle may be rendered still more evident by a numerical illustration T^t us take, for example, a blast furnace, into which 600 Uic feet of a ar^ b^^^^ minute ; suppose it to contain no ore, but merely coal or coke, and that t has been Sum ing long enough to have arrived at the equilibrium of temperature, and let us see Xt excess of temperature it would have if blown with air of 300° C. (572° F ) instead of ^ ing blown with air at 0° C. ^ ^' msieaaoi De- ..^^^.^''^'''^f^^'^^^i^^^.d^rthe mean temperature and pressure, weigh a little more than 4.0 pounds avoirdupois ; they contain 10-4 pounds of oxygen, which ^uld burn^e^ nearly 4 pounds of carbon, and disengage 16,000 times as mLh heat asTould raise bT one degree Cent, he temperature of two pounds of water. These 16,000 portions of heat produced every minute, will replace 16,000 other portions of heat, diWipa^by he sfdes of the f^.,rnace, and employed in heating the gases which escape from its mouth TWs must take place in order to establish the assumed equilibrium of calork. n the 45 pounds of air be heated beforehand up to 300° C, they will contain about ^'thlw '^''."Z '^' ^'^' "^ '^' '^'^^^ disengaged by the combuJti^, and there wS i^nn ;^J^ ^^^ .same space one eighth of heat more, which will be ready to operate of 3n(?>"r ''• '' ""f '"^ ''' range, and to heat them one eighth more. This the^blast Jh/nrT;n ^'!^' ^ tcmpcrature which is nine eighths of the blast at zero C, or at even from 19^no^^^T?^P??;'^ temperature; and as we may reckon at from 2200° lo 2700«> F. Orom 1200° to 1500° C), the temperature of blast furnaces worked in the common waV tr360°T' ' '^' blast produces an increase of temperature equal to from I'o^ r^r^ZJV'^Zu ^P.P^^*^'^^^**'^ i™™ense effects which this excess of temperature may produce m melallurgic operations, we must consider that ofYen only a few degrees more temperature are required to modify the state of a fusible body, or to determine theX of affinities dormant at lower degrees of heat. Water is solid at 1« under 3^ F h i£ liquid at 1° above. Every fusible body has a determinate melting point, a veryVei 1076 mojs. degrees aboYe which it is quite fluid, though it may be pasty below it. The same ott servation applies to ordinary chemical affinities; charcoal, for example, which reduces the greater part of metallic oxydes, begins to do so only at a determinate pitch of tem- perature, under which it is inoperative, but a few degrees above, it is in general lively and complete. It is unnecessary, in this article, to enter into any more details to show the influence of a few degrees of heat, more or less, in a furnace, upon chemical opera- tions, or merely upon physical changes of state. These consequences might have been deduced long ugo, and industry might thus have been enriched with a new application of science ; but philosophers have been and still are too much estranged from the study of the useful arts, and content themselves too much with the minutiae of the laboratory or theoretic abstractions. Within the space of 7 years the use of the hot blast has been so much extended in Great Britain, as to have enabled'many proprietors of iron works to add 60 per cent, to their weekly production of metal, to diminish the expenses of smelting by 50 per cent., and, in many cases, to produce a better sort of cast iron from indifferea* materials. 797 ^^^ The fieures here given represent the blast furnace, and all the details of the air heatiny , at one view. Fig. 794 is a vertical section of the furnace and the apparatus ; fig. 796 repre- sents the plan at the height of the line 1, 2, of fig. 794. The blowing machine, which is not shown in this view, injects the air through the pipe A, into the regulator chamber r, fig. 796 ; the air thence issues by the pipe b, proceeds to c, where it is subdivided into two portions ; the one passes along the pipe c d to get to the tuyere t, the other passes behind the furnace, and arrives at the tuyere t' by the pipe c e f. These pipes are distributed in a long furnace or flue, whose bottom, sides, and top are formed with fire-brick, where they are exposed to the action of the flame of the three fires x, v, z. The flame of the fire x plays round the pipe b at its entrance into the flue, and quits it only to go into the chimney h ; that of the fire y acts from the point d to the same chimney, passing by the elbow c ; that of the fire z acts equally upon f and H, in passing by the elbow e. Disposition of the fires and furnace. — Fig, IRON. 1077 797 represents, upon a scale three times larger than fig. 796, the section of the fire I, of which the plan is seen in^g. 796, and the elevation in fig. 794 ; as also in the outside view of the blast furnace, fig. 800. « j'-* j «» aisso in ine ♦». '^i;^./'"'*^^ ^^ *^^5 ^^^ ^"^^ js introduced by the door p, fig. 794 ; the flame rises abova en^ih 1 rah^it'n ?T''^1 "J""^ ll^^ "'^"^'^^ «"« towards the chimney h through J Ih^io nio? r ? • ' "'''^;- 'J^ ^^^ S'*^^' ^^<^ ^"^•""'^e « on each side supported b? obh.ng plates of cast-iron which are bound together by 4 upright ribbed orTa thered bars, also on each side; these bars, n, being bou'nd together by iron rods furnished wUh ^c:t:^:^V^i^^'" ^^^^ ^^^^ ^^^)- Beyond this d^istance,the'ou"t:iS:1,f^;S^ V^^ ^J^^yf""^ ^ have exactly a like disposition with the above, i^tg. 797 indicates the dimensions and the curvature of the arch above the erate near Iron'casfnV.-^^* ^'' ''^'''''''' ^'^ section of the furnace and of the pipe bSLe^t- Jxll^ ^^^^ ^^ ''".k"*u^ '' °"!y ^^''"^ 3 ^^^^ ^»^« «^ the bottom, and that the elevation ill I- *^k'^^^' ^^"^" l' "° "'^''^ t^**^ 30 inches. Perhaps it might be made a ittle wider xv.th advantage ; the combustion would be more vigorous aTd effective and If the sides also were a little thicker, the heat would be better Confined. ' Ihe distance from the fire-place x to the chimney h, is 43| feet. — T to the point c, is J3 — — z to the chimney, is 29 — including the thifktftl:? o/JA.^t;,.,.-At B the pipe is 18 inches diameter ouTsidl, anVonT fnch thick of metal, and it tapers to c ; from c to d and from d to c the pines are onh 1 1 inih^ in external diameter, and three fourths of an inch thick- thev Le 5 fee? ?n„a „„ T rlr'V"''"'^ ^'T^^' ^'^ «^^--y ones,inrthoseycomp^^:^^^^^^^^^^ play for the expansion and contraction. One of the^e is seen between n«nH/ 1 ^L IhTAJ-'".' ""'T '^^"^^'^ ^ '^"^ ^> ^-^ - fourth between E and p These pipes a^d tion and contraction of the pipes with changes of temperature. ^il.V''^'' f '" ^•'t*"*^^^ <^^8t«»"s «r Oiction-roUers of cast-iron are placed tocarrv the nine, a'refhown Tl til tJV'unr ^^'' T^^ ^'^ «T ^^ '^« «"- T^se ^a'sl^ r^oiroVo • I V^o * ' h ^' ^^' ^^^5 ®"® ^^ them IS shown separate uoon a larger scale at g, m fig. 798, as also the plate or rail s, on which it runs. ^ ^" allnxi .h^^v^f^ ^ T l^^""^^^^ ^"^^^ ^^^ P'P« ^^'""^ them ; this is truly bored so as to n ifnn • /h ''k ^"1 ''r ^^^ *"y^''^ t°'"*^« tightly backwards and forwards i^'it like a piston in the barrel of a pump; a diaphragm moreover prevents the tuv^re Lm K^t^J drawn or forced entirely out of its tube. At the side of te tube here ifa iaTorS ^'oLr^n-LX^^^^^^^ ^^^"^^ -^- ^'^ 6I2thdet: o^Atert'.^ ^TL^e l» ^AV ^\ ^'i^rP^aces of the air-heating furnaces the pipes are at a cherrv-red heat • nnil lest they should be burned, they are there coated with a lute of firlclay^as shown 'n.^^ K, ;n fig. 797. By this means the air is kept up at the heat of 350° C nr fi^ I little above the boiling point of quicksilver. ^'' ""^ ^^^ ^"^ * f„r^«^r'''^ °-^ "A"'"^ preMur..-The blowing-machine belonging to the above blast furnace is moved by a water wheel of 22 horse power; the nistons are 4 fp!t InT f have a 31-feel stroke, work double, and expel 1200 cubic feet of air in t^. 1^'^ ;»o ;r«„ ■ u* u^ °^ cast-iron daily, with an expenditure of 255 of coke for 1 of cast-iron ; m which case the coke amounted to 9 tons daily The returns by the hot blast compared with those by the cold are therefore «.» th« numbers 3 and 2, which shows an advantage by the former plan of 50 ner cen^ tk consumption of fuel in the two case^ Jq «c « #« o '" • pian oi XM per cent. The 1 1 ««H L«» i-. 1 . , ^^ '^ ^^ ° to 9, being a saving in this article of about »Z^nU ?5V'.f 'i*'" ^^'^""^ '^^ «"^P»^"r in the coal. ^ ***""^ for^hiVe Thfh ?■ -^"'"^ "-^ '^' •^^^'"""^^ mo«/A.-This system is mounted in Staf- na.^ «n^ ;J ^^^'"i^ apparatus is there set immediately upon the mouth of he fur- nace ; and is composed of two large cast-iron cylinders of (he'same length, the one witWn '4- 1078 IRON. moN. the other, leaving a space between them. This annular interval amounts to 16 inches and it is closed at top and bottom: but the innermost cylinder is open at both ends, and forms, indeed, the vent of the chimney or furnace. Ii carries nine rows of pipes, three in each row, which cross its interior, and open into tne annular space. The Eame of the furnace passes between the intervals of the cross pipes, heatmg them, and also the two upright cylinders with which they are connected. The air ot the blowing machine arrives by a vertical pipe, which is placed at the back of the lur- nace ; it enters into the above annular space, and thence circulates, with more or Jess velocity, through the 27 cross tubes, upon which the flame is continually playing; lastly, it is drawn through to the bottom of the annular space ; the two tubes which conduct it to the two tuyeres, pass down within the brickwork of the furnace, and thus prevent the dissipation of its heat. • .v r Below this heating apparatus there is a door for putting the charges into the furnace. The above arrangement does not seem to be the best for obtaining the greatest possi- ble heat for the blast, nor for favoring the free action of the furnace ; but it illustrates perfectly well the principle of this application. A serpentine movement m a long bent hot channel would be much better adapted for communicating heat to so bad a conductoi as air is known to be. ^ , , ^ i i • -n^.. In the month of July, 1836, I paid a visit to Codner Park and Butterly works, in Der- byshire, belonging to the eminent iron-masters, Messrs. Jessop & Co., where l wat kindly permitted not only to study the various processes of the manufacture of cast and wrought iron, but to inspect the registers of the products of cast iron in their blast furnaces for several years back. It appeared that in the year 1829, only 29 tons o cast-iron were made weekly in each of the blast furnaces at Codner Park. iney were then worked with coke, and blown with cold air. Each ton of iron requirea for its production, at that time, 6-82 tons of coals, made into coke for snieltmg ; with 2-64 of roasted iron ore (carbonate), caUed mine ; and 0-87 of limestone, the castine of ^In 1835 knd 1836, the same furnaces turned out weekly 49 tons of cast-iron each; ant every ton of iron required for its production only 3 tons of coal (not made into coke)} 2*72 tons of mine ; and 0*77 of lime. r i • o-:^ In 1829, and for many years before, as well as one or two after, each ton of coals is sa d to have cost for coking'the sum of 6,., whence the 6-82 tons ^^ ^^^^^^^.J^'.^VtnZv nr^me coke for smelting one ton of iron, cost fully 40.. in coking alone, m addition to their prime cost. The saving in this respect, therefore, is 40.. upon each ton of iron, besides the saving of fully half the coal, and the increased produce of nearly 60 per cent, of metal per week. The iron-master pays the patentee Is. upon every ton f^ »^«"^/*!;^*» *1^ makes, and, at the prices of 1836, he lessened his expenses by at least 30*. or 40*. per ton by the patent improvement. , , - , The following tabular view of the progression m the management and results of the hot blast, is given by M. Dufrenoy, after visiting the various iron works m this country where it had been introduced. « At the Clyde iron works, near Glasgow ; in 1829, when the combusUon was effected by Che cold air blast, — Coal. ' Tons. cwt. lbs There were consumed, for smelting, 3 tons of coke, equivalent to " ? ^? 2 — for the blowing engine - - - - i u / 1079 4 Total coal per ton of iron - 7 Limestone - " . " ® In 1831, with the hot blast at 450° F., coke being still used in smelting,— There were consumed, for smelting, 1 ton, 18 cwt. of coke, equiva- lent to • - - ' . ^' . ' \ for heating the air, 5 cwt. i for the blowing engine, 7 cwt. 4 lbs. > Total coal per ton of iron Limestone - - - In July, 1833, with the hot blast at 612? F., raw coal alone being used for smelting, — There were consumed : for smelting ----- for heating the air - — for the blowing engine - - - - 13 7 Wl 6 12 4 4 2 18 9 8 11 4 2 Total coal per ton of iron Limestone - 2 19 2 -070 « At the last period the use of hot air had increased the make of the furnaces by more than one third, and had consequently produced a great saving of expense in the article of labor. The quantity of blast necessary for the furnaces was also sensibly diminished ; for a blowing engine of seventy-horse power, which, in 1829, served only for three blast furnaces, was now sufficient for the supply of four. " On comparing these several results, we find that the economy of fuel is in proportion to the temperature to which the air is raised. As for the actual saving, it varies in every work, according to the nature of the coal, and the care with which the operation is conducted. "This process, though it has been four years in use in the works near Glasgow (which it has rescued from certain ruin), has scarcely passed the borders of Scotland ; the marvellous advantages, however, which it has produced, are beginning to triumph over prejudice, and gradually to extend its use into the different English iron districts. There are one-and-twenty works, containing altogether sixty-seven blast furnaces, in which hot air is used. The pig iron run out of these furnaces is generally No. 1, and is fit for making the most delicate castings. This process is equally applicable to forge pigs for the manufacture of bar iron ; since in order to obtain this quality of iron, it is only necessary to alter the proportion of fuel and mineral. In the forges of the Tyne iron- works, near Newcastle, and of Codner Park, near Derby, pigs made in furnaces blown by hot air, are alone used in the manufacture of bar iron. " In the side of the tuyere pipe a small hole is made, by means of which the heat of the air may be ascertained at any moment. This precaution is indispensable, it being of unportance to the beneficial use of hot air, that it be kept at a uniformly high temperature. With a proper apparatus the air is raised to 612 degrees Fahr., which is a greater heat, by several degrees, than is necessary for the fusion of lead." « At Calder works the consumption of fuel has diminished in the proportion of 7 tons 17 cwts. to 2 tons 2 cwts. There has also been a great diminution of expense in limestone, of which only 5§ cwts. are now used, instead of 13 cwts., which were used in 1828. This decrease results, as I have already said, from the high temperature which the furnace has acquired since the introduction of hot air. "The quantity of blast has been reduced from 3500 cubic feet per minae, to 2627 cubic feet ; the pressure also has been reduced from 3^ to 2| lbs." 0/ the refinery of cast-iron, or its conversion into bar-iron, in England.— This operation IS naturally divisible into three distinct parts. The first, or the finery properly soeakine, IS executed in pecuhar furnaces called running out fires ; the second operation completes the first, and is called puddling; and the third consists in welding several iron lars to- gether, and working them under forge hammers, and between rolls. 1. The finery furnaces are composed of a body of brickwork, about 9 feet square • rising but little above the surface of the ground. The hearth, placed in the middle, 'is two feet and a half deep; it is rectangular, being in general, 3 feet by 2, with its greatest side parallel to the face of the tuyeres ; and it is made of cast iron in four plates. On the side of the tuyeres there is a single brick wall. On the three other sides, sheet iron doors are placed, to prevent the external air from cooling the metal, which is almost always worked under an open shed, or in the open air, but never in a space surrounded by walls The chimney, from 15 to 18 feet high, is supported upon four columns of cast iron- its Imtcl is four feet above the level of the hearth, in order that the laborers mav work with- out restraint. The number of tuyeres is from two to three; they are placed at the height of the lie of the crucible or hearth, and distributed so as to divide its length into equal parts • their axes being inclined towards the bottom, at an angle of from 25° to 30°, so as to point upon the bath of melted metal as it flows. The cast-iron nose-pipe is incased, and water IS made to cuculate in the hollow space by means of cyUndrical tubes ; being introduced by one tube, and let oflf by another, so as to prevent the tuyeres from getting burned in the ])rocess. Two nozzles are usually placed in each tuyere, to render the blast constant and uni- f jrm ; and for the same end, the air impelled by the beUows, is sometimes received at r .nJ!>^^^^*°/* '^^ quantity of air blown into the fineries is considerable ; being nearly 400 cubic feet per minute for each finery ; or about the eighth part of the consumiv tion of a blast furnace. ^ The finery furnace, or running out fire, is represented in figs. 801 and 802. It is a smelting hearth, in which by first fusing and then cooling gray cast iron in a pecuUar way, It IS converted into white cast iron, caUed fine iron, or fine metal, of the quality of forge pig, for makmg malleable iron by the puddUng process. The furnace resembles the forge hearth employed m Germany and France for converting forge pig into wiou *n r^^ as it is called, by being cast in iron moulds, for rolling iion into plates or hoops, e, e, e, e, are strong screws with rectangular threads, which work by means of a wrench or key, into the nuts c' e' e' «', fixed in the standards ; they serve to regulate the height of the plummer blocks or bearers of the ^dgeons, and thereby the distance between the upper and under cylinders. / is a junction shaft ; g. g, g, are solid coupling boxes, which embrace the two separate ends of the shafts, and make them turn together. A, A, are junction pinions, whereby motion is communicated from the driving shaft /, through the under pinion to the upper one, and thus to both upper and imder rolls at once, t, i, are the pinion standards in which their shafts run ; they arc smaller than the uprights of the rolls, fe, fe, are screws for fastening the head pieces / te the top of the pinion standards. All the standards are provided with sole plates m, frherehy they are screwed to the foundation beams n, of wood or preferably iron, as shown by dotted lines ; o o are the binding screw bolts. Each pair of rolls at work is kept cool by a small stream of water let down upon it from a pipe and stop-cock. In the cylinder drawing, the workman who holds the ball in tonffs, passes it into the first of the elliptical grooves ; and a second workman on the other side of the cylinders, receives this lump, and hands it over to the first, who re-passes it between the rollers, after bringing them somewhat closer to each other, by giving a turn to the adjusting pres- sure screws. After the lump has passed five or six times through the same groove, it has got an elliptical form, and is called in England a bloom. It is next passed through a second groove of less size, Avhich stretches the iron bar. In this state it is subjected to a second pair of cylinders, by which the iron is drawn into flat bars, 4 inches broad and half an inch thick. Fragments of the ball or bloom fall round about the cylinders ; which are afterwards added to the puddling charge. In a minute and a half, the rude lump IS transformed into bars, with a neatness and rapidity which the inexperienced eye can hardly follow. A steam engine of thirty-horse power can rough doum in a week, 200 tons of coarse iron. This iron, called mill-bar iron, is however of too inferior a quality to be employed in any machinery; and it is subjected to another operation, which consists in welding several pieces together, and working them into a mass of the desired qualitv. The iron bars, while still hot, are cut by the shears into a length proportional to the size of iron bar that is wanted ; and four rows of these are usually laid over each other into a heap or pile, which is placed in the '^c-heating furnace above described, and exposed to a free circulation of heat ; one pile being set crosswise over another. In a half or three quarters of an hour, the iron is hot enough, and the pieces now sticking together, are carried in successive piles to the bar-drawing cylinders, to be converted into strong bars, which are reckoned of middle quality. When a very tciigh iron is wanted, as for anchors, another welding and rolling must be given. In the re-heating ovens, the loss is from 8 to 10 per cent, on the large bar iron, and from 10 to 12 in smaUer work. A ton of iron con- sumes in this process about 150 lbs. of coals. It is thought by many that a purer iron is obtained bv subjecting the balls as they come out of the puddling furnace, to the action of the hammer at first, than to the roughing rollers ; and that by the latter process vitrified specks remain in the metal, which the hammer expels. Hence, in some works, the balls are first worked under the forge- hammer; and these stampings being afterwards heated in the form of pies or cakes piled over each other, are passed through the roughing rollers. Having given ample details concerning the manufacturing processes used in England for making cast iron, it may be proper to subjoin a few observations upon its chemical constitution. It has been generaUy believed and taught that the dark gray cast iron No. 1 or No. 2, contains more carbon than the white cast iron ; and that the superior quality of the former in tenacity and softness, is to be ascribed to that excess. But the distinguished German metaUurgist, M. Karsten, in his instructive volume, " Hand- buch der Eisenhiittenkunde," or manual of the art of smelting iron ores, has proved, on the contrary, that the white cast iron contains most charcoal ; that this substance exists m It in a state of combination with the whole body of the iron ; that the foliated or la- mellar white cast iron contains as much carbon as iron can absorb in the liquid state- and that this constitutes a compound of 4 atoms of iron combined with 1 of charcoal, or 1124-6 • or 51 per cent. ; whereas the dark gray cast iron contains generally from 3 to 4 per cent., in the state of plumbago merely dispersed through the metal. He has further confirm^ his opinion, by causing the white variety to pass into the gray, and recipro- cally. Thus, dark gray cast metal melted and suddenly cooled, gives a silvery white metal, hard and brittle. On the other hand, when the white cast iron is cooled very slowly after fusion, the condition of the carbon in it changes, and a dark ?ray cast iron is obtamed. These phenomena show that the graphite or plumbago, which requires a high temperature for its formation, cannot be produced but bv a slow coolinjr, which al- lows the carbon to agglomerate itself in the iron in the state of graphite; while under a rapid congelation, the carbon remains dissolved in the mass, and produces a white metal. Hence we may understand how each successive fusion of dark gray iron hardens and whitens V- ?"1 *"/io"t^^t ^^Jth coke, by completing that chemical dissolution of the carbon on which the white state depends. In the manufacture of the blackest No. 1 cast iron, it sometimes happens that a con- siderable quantity of a glistening carburet of iron appears, floatin? on the top of the metal as it is run out into the sand-moulds. This substance is called kish by the iLnghsh workmen ; and it affords a sure test of the good state of the furnace and qualitv of the iron. ^ ■' The most remarkable fact relative to the smelting of cast iron, is the difference of pro- dnct between the workings of the summer and the winter season, though all the material and machinery be the same. In fact, no cold-blast furnace will carrv so great a burder 1088 IRON. in summer as in winter, that is, afford so gieat a product of metal, or bear so great • charge of ore with the same quantity of coke. This diiierence is undoubtedly due to th€ dilated and humid state of the atmosphere in the warm season. A very competent judg« cf this matter, states the diminution in summer at from one fifth to one seventh, indepen dcntly of deterioration of quality. Some of the foreign irons, particularly certain Swedish and Russian bars, are im- ported into Great Britain in large quantities, and at prices much greater than those of the English bars, and therefore the modes of manufacturing such excellent metal deserve examination. All the best English cast steel, indeed, is made from the hoop L iron from Dannemora, in Sweden. The processes pursued in the smelting works of the Continent have frequently in view to obtain from the ore malleable iron directly, in a pure or nearly pure state. The furnaces used for this purpose are of two kinds, called in French, 1. Fetiz de Loupcsy or Forges Catalanes ; and 2. Fourneaux H piece, or Forges Mlemaivies. In the Catalan, or French method, the ore previously roasted in a kiln is aflen^'ards strongly torrefied in the forge before the smelting begins ; operations which follow in immediate succession. Ores treated in this way should be very fusible and very rich ; such as black oxyde of iron, hematites, and certain spathose iron ores. From 100 parts of ore, 50 of metallic iron have been procured, but the average product is 35. The furnaces employed are rectangular hearths, /g«. 811, and 811, the water-blowing 810 811 03 machine being employed to give the blast. See Metallurgy. There are three varieties of this forge ; the Catalan, the Navarrese, and the Biscayan. The dimensions of the first, the one most generally employed, are as follows : 21 inches long, in the lUrection p f,fig. 811; 18^ broad, at the bottom of the hearth or creuset,in. the line A B ; and 17 inches deep,yi^. 810. The tuyere, q jo, is placed 9^ inches above the bottom, «o that its axis is directed towards the opposite side, about 2 inches above the bottom. But it must be moveable, as its inclination needs to be changed, according to the stage of the operation, or the quantity of the ores. It is often raised or lowered with pellets of clay ; and even with a graduated circle, for the workmen make a great mystery of this matter. The hearth is lined with a layer of brasque (loam and charcoal dust worked together), and the ore after being roasted is sifted ; the small powder being set aside to be used in the course of the operation. The ore is piled up on the side opposite to the blast in a sharp saddle ridge, and it occupies one third of the furnace. In the re- maining space of two thirds, the charcoal is put. To solidify the small ore on the hearth, it is covered with moist cinders mixed with clay. The fire is urged with moderation during the first two hours, the workman being continually employed in pressing down more charcoal as the former supply burns awa}-, so as to keep the space fiill, and prevent the ore from crumbling down. By a blast so tempered at the beginning, the ore gets well calcined, and partially reduced in the way of cementation. But after two hours, the full force of the air is given; at which period the fusion ought to commence. It is easy to see whether the torre- faction be sufficiently advanced, by the aspect of the flame, as well as of the ore, which becomes spongy or cavernous ; and the workman now completes the fusion, by detaching the pieces of ore from the bottom, and placing them in front of the tuyere. When the fine siftings are afterwards thrown upon the top, they must be watered, to prevent their being blown away, and to keep them evenly spread over the whole surface of the light fuel. They increase the quantity of the products, and give a propel fusibility to the scorioe. When the scoriae are viscid, the quantity of siftings must be diminished ; but if thin, they must be increased. The excess of slag is allowed to run oflT by the chic or floss hole. The process lasts from five to six hours, after which the pasty mass is taken out, and placed under a hammer to be cut into lumps, which are afterwards forged into bars. Each mass presents a mixed variety of iron and steel ; in proportions which may be modified at pleasure ; for by using much of the siftinsrs, and making the tuj'cre dip to .vanJs the sole of the hearth, iron is the chief product ; but if the operation be con IRON. 1089 ducted slowly, with a small quantity of siftings, and an upraised tuvtre, the quantity 01 steel IS more considerable. This primitive process is favorably' spoken of by M. Brongniart. The weight of the lump of metal varies from 200 to 400 pounds. As the consumption of charcoal is very great, amounting in the Palatinate or Rheinkreis to se^-en linies the weight of iron obtained, though in the Pyrenees it is only thrice, the Catalan forge can be profitably employed only where wood is exceedingly cheap and abundant. ^ ^ * The Fmeauxdpihe of the French, or Stuck-ofen of the Germans, resembles ^^.885 (Copper) ; the tuyere (not shown there) having a dip towards the bottom of the hearth, where the smelted matter collects. When the operation is finished, that is at least once m eveiy 24 hours, one of the sides of the hearth must be demolished, to take out the pasty mass of iron, more or less pure. This furnace holds a middle place in the treatment of iron, between the Catalan forge and the cast-iron j7ow-q/c«, or hi-h-blast fhT^'^'tV i'f »;«^'^-oA« are from 10 to 15 feet high, and about 3 feet in diameter at the hearth. Most usually there is only one aperture for the tuyere and for working- with a smaU one for the escape of the slag; on which account, the bellows are removid o make way for he lifting out of the lump of metal, which is done through an opening left on a level with the sole, temporarily closed with bricks and potters' clay, whUe the furnace is in action. ^ ^» "*** hnnni' "" WK ^''""^ H^""'^!' r^- *-^ ^™ce fiUed with charcoal, fire is kindled at the fn nh^r'n.t r'^'^"' ^\^^^^^ IS lu combustiou, the roastcd ore is introduced at the top m alternate charges with charcoal, tiU the proper quantity has been introduced. The ore iron Ar'T i, ^^'^^"ever it comes opposite to the tuyere the slag begins to flow, and the nrnnnrr^ dowu and coUccts at the bottom of the hearth into the mass or stuck and i^ proportion as this mass increases, the Jloss-hole for the slag and the tuyere s raisS higher When the quantity of iron accumulated in the hearth is judg^ to be s«fficTent h^ r^lr'f"^"^ '-^P^'^' '^^ r"T ^'^ '^^^^ ^^' '^' "ttle brick waU^is taken dowi, and the mass of iron is removed by rakes and tongs. This mass is then flattened und^; the hammer, mto a cake from 3 to 4 inches thick, and is cut into two lim^ps, whTch are sul^ mitted to a new operation ; where it is treated in a peculiar refinery, lined with char^al Srasque, and exposed to a nearly horizontal blast. The above maS sei^eT in the^^ LlTnfT T^%'', ^'"'"^ ^'^T *^^ '^y^^^' ^ P^^ti^'^ «f the meial flows iown to tie bottom of the hearth, loses its carbon in a bath of rich slags or fused oxydes and foiros thereby a mass of iron thoroughly refined. The portion that remains Tthe tongsZ! nishes steel, which is drawn out into bars. ^ This process is employed in Carniola for smeltin* a erannl^r nvv,lo «r ,V/.« ti. or ^uck amounts to from 15 to 20 hundred weigh," ?Srtaeh%tafrof STtSf Eight strong D,en are required to lift it out, and to earr,- it under aCge hammer wS eras aWe'tecribel'" The^r '"'"• ''"'^ "« afterwards refined a^dZw i^S oars as aoove oescnbed. Ihese furnaces are now almost n>n»r>iiU' o>.onj„.~] _ .u Continent, in favor of charcoal Mgh or blast furmces S^^'^^i abandoned on the tig. 385 represents a shachtofin (but without the tuyere, which may be sunoosed to h, m the usual pace), and is, UUe all the continental Hail, F ■?•" '"^'Se is put in at the th™at!Te„ the slm^! :n :f xtr r5:=e''^itri^^^^^^^ fhnhSn ^^P^'^I^V t>ottom of the hearth is constracted of two lar<'e stones and lr.n hT ^^'^ ""^ one great stone, caUed in German, rncksiem (black sSSe) whfch Sl French have corrupted into rustine. In other countries of th^ rvJ^f- V .u ' v V ® cast-iron, 130 pounds of chtLTwereioSfmed '" '^'f'"''^"""'" "^ '"O Po.unds of beUows., mounted with leather. *'"^"«»''<'- That furnace was worked with foi^e 1090 moN. The decarburation of cast-iron is merely a restoration of the carbon to the 9url*ce, m tracing inversely the same progressive steps as had carried it into the interior during the smelling of the ore. The oxygen of the air, acting first at the surface of the cabt metal, upon the carbon which it finds there, burns it : fresh charcoal, oozing from the interior, comes then to occupy the place of what had been dissipated ; till, finally, the -yvhole car- bon is transferred from the centre to the surface, and is there converted into either car- Iwnic acid gas, or oxyde of carbon ; for no direct experiment has hitherto proved which of these is the precise product of this combustion. This diffusibility of carbon through the whole mass of iron constitutes a movement by means of which cast-iron may be refined even without undergoing fusion, as is proved by a multitude of phenomena. Every workman has observed that steel loses a portion of its steely properties every time it is heated in contact with air. On the above principle, cast-iron may be refined at one operation. Three kinds of iron are susceptible of this continuous process : — 1. The speckled cast-iron, which contains such a proportion of oxygen and carbon as with the oxygen of the air and the carbon of the fuel may produce sufficient and complete saturation, but nothing in exce&i 2. The dark gray cast-iron. 3. The white cast-iron. The nature of the crude met*i requires variations both in the forms of the furnaces, and in the manipulations. Indeed, malleable iron may be obtained directly from the ores by one fusion. This mode of working is practised in the Pyrenees to a considerable extent. All the ores of iron are not adapted for this operation. Those in which the metallic oxyde is mixed with much earthy matter, do not answer well; but those composed of the pure black onys^y red oxyde, and carbonate, succeed much better. To extract the metal from such ores, it is sufficient to expose them to a high temperature, in contact either with charcoal, or with carbonaceous gases ; the metallic oxyde is speedily reduced. But when several earths are present, these tend continually, during the vitrification which they suffer, to retain in their vitreous mass the unreduced oxyde of iron. Were such earthy ores, as our ironstones, to be put into the low furnaces called Catalan^ through which the charges pass with great rapidity, and in which the contact with the fuel is merely momentary, there would be found in the crucible or hearth merely a rich metallic glass, instead of a lump of metal. In smelting and refining by a continuous operation, three diflerent stages may be dis- tinguished : 1. The roasting of the ore to expel the sulphur, which would be less easily separated afterwards. The roasting dissipates likewise the water, the carbonic acid, and any other volatile substances which the minerals may contain. 2. The deoxy- dizement and reduction to metal by exposure to charcoal or carbureted vapors. 3. The melting, agglutination, and refining of the metal to fit it for the heavy hammers where it gets nerve. There are several forges in which these three operations seem to be con founded into a single one, because, although still successive, they are practised at one single heating without interruption. In other forges, the processes are performed sepa- rately, or an interval elapses between each stage of the work. Three systems of this kind are known to exist: — 1. The Corsican method; 2. The Catalan with wood char- coal; and 3. The Catalan with coke. The furnaces of Corsica are a kind of semicircular basins, 18 inches in diameter, and 6 inches deep. These are excavated in an area, or a small elevation of masonry, 8 or 10 feet long by 5 or 6 broad, and covered in with a chimney. This area is quite similar to that of the ordinary hearths of our blast-furnaces. The tuyere stands 5 or 6 inches above the basin, and has a slight inclination down- wards. In Corsica, and the whole portion of Italy adjoining the Mediterranean shores, the iron ore is an oxyde similar to the specular ore of the Isle of Elba. This ore con- tains a little water, some carbonic acid, occasionally pyrites, but in small quantity. Be- fore deoxydizing the ore, it is requisite to expel the water and carbonic acid combined with the oxyde, as well as the sulphur of the pyrites. The operations of roasting, reduction, fusion, and agglutination, are executed in the same furnace. These are indeed divided into two stages, but the one is a continuation of the other. In the first, the two primary operations are performed at once ; — the reduction of a portion of the roasted ore is begun at the same time that a portion of the raw ore is roasted : these two substances are afterwards separated. In the second stage, the deoxydizement of the metal is continued, which had begun in the preceding stage ; it is then melted and agglutinated, so as to form a ball to b« submitted to the forge-hammer. The roasted pieces are broken down to the size of nuts, to make the reduction of the metal easier. In executing the first step, the basin and area of the furnace must be lined with a brasq-ue of charcoal dust, 3, 4, or even 5 inches thick : over this brusque a mound is raised with lumps of charcoal, very hard, and 4 or 5 inches high. A semi- circle is formed round the tuj^ere, the inner radius of whicli is 5 or 6 inches. This mass oC charcoal is next surrounded with mother pile of the roasted and broken ores, whicli IRON. 1091 must be covt-rd with charcoal dust. The whole is sustained with large blocks of the raw ore, which form externally a third wall. These three piles of charcoal, with roasted and unroasted ore, are raised m three suc- cessive beds, each 7 inches thick : they are separated from each other by a layer of char- coal dust of about an inch, which makes the whole 24 inches high. This is afterwards covered over with a thick coat of pounded charcoal. The blocks of raw ore which compose the outward wall form a slope ; the larger and stronger pieces are at the bottom, and the smaller in the upper part. The large block* are sunk very firmly into the charcoal dust, to enable them better to resist the pressure from within. On the bottom of the semicircular well formed within the charcoal lumps, kindled pieces are thrown, and over these, pieces of black charcoal ; after which the blast of a water- blowing machine (trompe) is given. The fire is kept up by constantly throwing char- coal into the central well. At the beginning of the operation it is thrist down with wooden rods, lest it should affect the building ; but when the heat becomes too intense for the workmen to come so near the hearth, a long iron rake is employed for the pur- pose. At the end of about 3 hours, the two processes of roasting and reduction are com- monly finished : then the raw ore no longer exhales any fumes, and the roasted ore, being softened, unites into lumps more or less coherent. The workman now removes the blocks of roasted ore which form the outer casing, rolls them to the spot where they are to be broken into small pieces, and pulls dowa ihe brasque (small charcoal) which surrounds the mass of reduced ore. The second operation is executed by cleaning the basin, removing the slags, covering the basin anew with 2 or 3 brasques (coats of pounded charcoal), and piling up to the right and the left, two heaps of charcoal dust. Into the interval between these conical piles two or three baskets of charcoal are cast, and on its top some cakes of the reduced crude metal being laid, the blast is resumed. The cakes, as they heat, undergo a sort of liquation, or sweating, by the action of the earthy glasses on the unreduced black oxyde present. Very fusible slags flow down through the mass ; and the iron, reduced and melted, passes finally through the coals, and falls into the slag basin below. To the first parcel of cakes, others are added in succession. In proportion as the slags pro- ceeding from these run down, and the melted iron falls to the bottom, the thin slag is run . off by an upper overflow or chio hole, and the reduced iron kept by the heat in the pasty condition, remains in the basin : all its parts get agglutinated, forming a soft mass, which is removed by means of a hooked pole in order to be forged. Each lump or bloom of malleable iron requires 3 hours and a half for its production. The iron obtained by this process is in general soft, very malleable, and but little steely. In Corsica four workmen are employed at one forge. The produce of their labor is only about 4 cwts. of iron from 10 cwts. of ore and 20 of charcoal, mingled with wood of beech and chestnut. Though their ore contains on an average 65 per cent, of iron, only about 40 parts are extracted ; evincing a prodigious waste, which remains in the slags. The difference between the Corsican and the Catalonian methods consists in the latter roasting the ore at a distinct operation, and employing a second one in the reduction agglutination, and refining of the metal. In the Catalonian forges, 100 pounds of iron are obtained from 300 pounds of ore and 310 pounds of charcoal; belhg a produce of only 33 per cent. It may be concluded that there is a notable loss, since the sparry iron ores, which are those principally smelted, contain on an average from 54 to 56 per cent, of iron. The same ores, smelted in the ordinary blast furnace, produce about 45 per cent' of cast iron. . On the Continent, iron is frequently refined from the cast metal of the blast fur- naces by three operations, in three diflerent ways. In one, the pig being melted, with aspersion of water, a cake is obtained, "which is again melted in order to form a second cake. This being treated in the refinery fire, is then worked into a bloom. In another system, the pig iron is melted and cast into plates : these are melted anew in order to obtain crude balls, which are finaUy worked into blooms. In a third mode of manufacture, the pig-iron is melted and cast into plates, which are roasted, and then stronglv heated, to form a bloom. ^ The French fusible ores, such as the silicates of iron, are very apt to smelt into white cast iron. An excess of fluxes, light charcoals, too strong a blast, produce the same results. A surcharge of ores which deranges the furnace and aflbrds impure slags mLxed with much iron, too rapid a slope in the boshes, too low a degree of heat, and too great con- densation of the materials in the upper part of the furnace ; all tend also to produce • white cast iron. In its state of perfection, white cast iron has a silver color, and a bnght metallic lustre. It is employed frequently in Germany for the manufacture of Jteel, and is then called steel Jhss, or lamellar foss, a title which it stiU retains, though it be hardly sUver white, and have ceased to be foliated. When its color takes a bluish- 1092 moN. gray tinge, and its fracture appears striated or splintery, or when it exhibits gray spota^ it is then styled Jlowerjloss, In a third species of white cast iron we observe still much lustre, but its color verges uiwn gray, and its texture is variable. Its fracture has been sometimes compared to that of a broken cheese. This variety occurs very frequently. It is a white cast iron, made by a surcharge of ore in the furnace. If the white color becomes less clear and turns bluish, if its fracture be contorted, and cofatains a great many empty spaces or air-cells, the metal takes the name of cavemous-JlosSf or tender-floss. The whitest metal cannot be employed for casting. When the white is mixed with the gray cast iron, it becomes riband or trout cast iron. The German refining forge, — Figs, 812, 813 represent one of the numerous refinerj 818 furnaces so common in the Hartz. The example is taken from the Mandelholz works^ in the neighborhood of Elbingerode. Fig. 813 is an elevation of this forge, d is the refinery hearth, provided with two pairs of bellows. Fig. 812 is a vertical section, showing particularly the construction of the crucible or hearth in the refinery forge d. c is an overshot water wheel, which gives an alternate impulsion to the two bellows a b by means of the revolving shaft c, and the cams or tappets dfeg, D, the hearth, is lined with cast iron plates. Through the pipe I, cold water may be introduced, under the bottom plate wi, in order to keep down, when necessary, the tem- perature of the crucible, and facilitate the solidification of the loupe or bloom. An orifice n, fi(^s. 812, 813, called the chio (floss hole), allows the melted slag or cinder to flow off from the surface of the melted metal. The copper pipe or nose piece p, fig. 811, conducts the blast of both bellows into the hearth, as shown at b ar, fig. 813, and d g p, fig. 811. The substance subjected to this mode of refinery, is a gray carbonaceous cast iron, from the works of Rothehiitte. The hearth d, bemg filled and heaped over with live charcoal, upon the side opposite to the tuyere x, figs. 812, 813, long pigs of cast iron are laid with their ends sloping downwards, and are drawn forwards successively into the hearth by a hooked poker, so that the extremity of each may be plunged into the middle of the fire, at a distance of 6 or 8 inches from the mouth of the tuyere. The workman pro- ceeds in this way, till he has melted enough of metal to form a loupe. The cast iron, on melting, falls down in drops to the bottom of the hearth ; being covered by the fused slags, or vitreous matters more or less loaded with oxyde of iron. After running them off by the orifice n, he then works the cast iron by powerful stirring with an iron rake (ringard), till it is converted into a mass of a pasty consistence. During this operation, a portion of the carbon contained in the cast iron combines with the atmospherical oxygen supplied by the beUovrs, and passes off in the form of carbonic oxyde and carbonic acid. When the lump is coagulated sufficiently, the workman turns it over in the hearth, then increases the heat so as to melt it afresh, meanwhile exposing it all round to the blast, in order to consume the remainder of the carbon, that IS, till the iron has become ductile, or refined. If one fusion should prove inadequate to tlus effect, two are given. Before the conclusion, the workman runs off a second stratum of vitreous slag, but at a higher level, so that some of it may remain upon the metal. The weight of such a loupe or bloom is about 2 cwts., being the product of 2 cwts. and l^ of pig iron ; the loss of weight is therefore about 26 per cent. 149 pounds of charcoal are consumed for every 100 pounds of bar iron obtained. The whole operation lasts about 5 hours. The bellows are stopped as soon as the bloom is ready ; this is immedi- ately transferred to a forge hanmier, such as is represented fig. 816 ; the cast iron head of which weighs 8 ot 9 cwts. The bloom is greatly condensed thereby, and discharges a considerable quantity of semi-fluid cinder. The lump is then divided by the hammer t , { IRON. 1093 ana a chisel into 4 or 6 pieces, which are reheated, one after another, in the same refinery fire, in order to be forged into bars, while another pi? of cast iron is laid in its place, to prepare for the formation of a new bloom. The above process is called by the Germans klump-frischen, or lump-refining. It differs from the durch-brech-frischen, because in the latter, the lump is not turned over in mass, but is broken, and exposed in separate pieces successively to the refining power of the blast near the tuyere. The French call this af. linage par portions ; it is much lighter work than the other. The quality of the iron is tried in various ways ; as first, by raising a bar by one end, with the two hands over one's head, and bringing it forcibly down to strike across a nar- row anvil at its centre of percussion, or one third from the other extremity of the bar ; after which it may be bent backwards and forwards at the place of percussion several times ; 2. a heavy bar may be laid obliquely over props near its end, and struck strongly with a hammer with a narrow pane, so as to curve it in opposite directions; or whUe heated to redness, they may be kneed backwards and forwards at the same spot, on the edge of the anvU. This is a severe trial, which the hoop L, Swedish iron, bears surprisin«'ly, emitting as it is hammered, a phosphoric odor, peculiar to it and to the bar in/Tof Ulverstone, which also resembles it, in furnishing a ?ood steel. The forging of a horse- shoe is reckoned a good criterion of the quality of iron. Its freedom from flaws is detected by the above modes ; and its linear strength may be determined by suspendin*' a scale to the lower end of a hard-drawn wire, of a given size, and adding wei^^hts tiU the wire breaks. The treatises of Barlow and Tredgold may be consulted with Advan- tage on the methods of proving the strength of different kinds of iron, in a great variety of circumstances. ^ o j Steel of cementation, or blistered steel and cast steel, are treated under the article Steex. But since m the conversion of cast iron into wrought iron, by a very sUght difference in the manipulations, a species of steel may be produced called naiural steeL I shaU describe this process here. Fig. 814 is a view of the celebrated steel iron works, caUed Konigshutte, (kins' s-forse). in Upper Silesia, being one of the best arranged in Germany, for smelUng iron ore by 11 TV 71 TV means of coke. The front shown here is about 400 English feet long, a a are two blast furnaces. A third blast furnace, all like the English, is situated to the left of one of the towers 6. 6 6 are the charging towers, into which the ore is raised by machinery from the level of the store-houses / /, up to the mouth of the furnaces aa ; cc point to the positions of the boilers of the two steam engines, which drive two cylinder bellows at / n nn n are arched cellars placed below the store-houses / /, for containing materials and tools necessary for the establishment. Figs. 810, 816, are vertical sections of the forge of Konigshiitte, for making natural steel ;^g. 810 being drawn in the line A b of the plan, ^g. 811. a is the bottom of the hearth, consisting of a fire-proof gritstone ; 6 is a space filled vrith small charcoal, damped with water, under which, at n, in fig, 815, is a bed of well rammed clay ; d is a plate of cast iron, which lines the side of the hearth called ruckstein (backstone) in German, and corrupted by the French into rustine ; f is the plate of the counter-blast ; g the ft.^- ^ 4k fi 1 1- , . P^*^^ °** ^^^ ^^^^ of the tuyere ; behind, upon the face ^, the fire-place or hearth is only 5| inches deep; in front as well as upon the ateral faces, it is 18 inches deep. By means of a mound made of dry charcoal, the pos- terior face d IS raised to the height of the face /. t, fig, 811, is the floss-hole, by which the slags are run off from the hearth during the workin- and through which, by removin- some bricks, the lump of steel is taken out when finished. klm are pieces of cast iron, for confining the fire in front, that is, towards the side where •f I!2 .f ^" v^*"**^^' "" '^ ^^^ ^^^^^ «^ the floor of the works; p a copper tuyere; it is situated 4| mches above the bottom a, slopes 5 degrees towards it, and advances 4 inches 12 lu A .°'',^e-place, where it presents an orifice, one half inch in horizontal lengtli, and one inch up and down ; q the nose pipes of two beUows, like those represented 1094 IRON. in fig. 813, and under Silver; the round orifice of each of them within the tuyere being one inch in diameter, r is the lintel or top arch of the tuyere, beneath which is seen the cross section of the pig of cast iron under operation. For the production of natural steel, a white cast iron is preferred, which contains little carbon, which does not flow thin, and which being cemented over or above the wind, falls down at once through the blast to the bottom of the hearth in the state of steel. With this view, a very flat fire is used ; and should the metal run too fluid, some malleable lumps are introduced to give the mass a thicker pasty consistence. If the natural steel be supposed to contain too little carbon, which is % very rare case, the metal bath covered with its cinder slag, is diligently stirred with a wo'vlen i)ole, or it may receive a little of the more highly carbureted iron. If it contains the right dose of carbon, the earthy and other foreign matters are made progressively to sweat out, into the supernatant slag. When the mass is found by the trial of a sample to be completely con- verted, and has acquired the requisite stitfness, it is lifted out of the furnace, by the open- ing in front, subjected to the forge hammer, and drawn into bars. In Sweden, the cast iron pigs are heated to a cherry-red, and in this state broken to pieces under the hammer, before they are exposed in the steel furnace. These natural steels are much employed on the Continent in making agricultural implements, on account of their cheapness. The natural steel of Styria is regarded as a very good article. Wootz is a natural steel prepared from a black ore of iron in Hindostan, by a process analogous to that of the Catalan hearth, but still simpler. It seems to contain a minute portion of the combustible bases of alumina and silica, to which its peculiar hardness when tempered may possibly be ascribed. It is remarkable for the property of assuming a damask surface, by the action of dilute sulphuric acid, after it has been forged and polished. See Damascus and Steel. Fig. 816 is the German forge-hammer ; to the left of 1, is the axis of the rotatory cam, 2, 3, consisting of 8 sides, each formed of a strong broad bar of cast iron, which are joined to- gether to make the octagon wheel. 4, 5, 6, are cast iron binding rings or hoops, ii.ade fast by wooden wedges. 6, 6, are standards of the frame-work e, /, wi, in which the helve of the forge-hammer has its fulcrum near u. h, the sole part of the frame. Another cast iron base or sole is seen at m. n is a strong stay, to strengthen the frame-work. At r two parallel hammers are placed, with cast- iron heads and wooden helves, s is the anvil, a very massive piece of cast iron. / is tho end of a vibrating beam, for throwing back the hammer from it forcibly by recoil, ar y is the outline of the water-wheel which drives the whole. The cams or tappets are shown mounted upon the wheel 6, g, 6. Analysis of irons. — Oxydized substances cannot exist in metallic iron, and the foreign substances it does contain are present in such small quantities, that it is somewhat difllcult to determine their amount. The most intricate point is, the proportion of carbon. The free carbon, which is present only in gray cast iron, may, indeed, be deter- mined nearly, for most of it remains after solution of the metal in acids. The combined charcoal, however, changes by the action of muriatic acid into gas and oil ; sulphuric acid also occasions a great loss of carbon, and nitric acid dissipates it almost entirely. Either nitre or chloride of silver may be employed to ascertain the amount of carbon ; but when the iron contains chromium and much phosphorus, the determination of the carbon is at- tended with many difficulties. The quantity of sulphur is always so small, that it can scarcely be ascertained by the weight of the precipitate of sulphate of barjles from the solution of the iron in nitro- muriatic acid. The iron should be dissolved in muriatic acid ; and the hydrogen, as it escapes charged with the sulphur, should be passed through an acidulous solution of acetate of lead. The weight of the precipitated sulphuret shows the amount of sulphur, allowing 13-45 of the latter for 100 of the former. In this experiment the metal should be slowly acted upon*by the acid. Cast iron takes from 10 to 15 days to dissolve, steel from 8 to 10, and malleable iron 4 days. The residuum of a black color does not contain a trace of sulphur. Phosphorus and chromium are determined in the following way. The iron must be dissolved in nitro-murialic acid, to oxygenate those two bodies. The solution must be evaporated cautiously to dryness in porcelain capsules, and the saline residuum healed I. i\ IRON. 1095 to redness. A little chloride of iron is volatilized, and the remainder resembles the red-brown oxyde. This must be mixed with thrice its weight of carbonate of potash, and fused in a platinum crucible j the quantity of iron being from 40 to 50 grains at most. The mixture, after being acted upon by boiling water, is to be left to settle, to allow the oxyde to be deposited, for it is so fine as to pass through a filter. If the iron con- tained manganese, this would be found at first in the alkaline solution; but man- ganese spontaneously separates by exposure to the air. The alkaline liquor must be supersaturated with muriatic acid, and evaporated to drj'ness. The liquor acidulated, and deprived of its silica by filtration, is to be supersaturated with ammonia ; when the alumina will precipitate in the state of a subphosphate. When the liquor is now supersaturated with acetic acid, and then treated with acetate of lead, a precipitate of phosphate of lead almost always falls. There is hardly a bit of iron to be found which does not contain phosphorus. The slightest trace of chrome is detected by the yellow color of the lead precipitate ; if this be white there is none of the coloring metal present. 100 parts of the precipitated phosphate of lead contain, after calcination, 19*4 parts of phosphoric acid. The precipitate should be previously washed with acetic acid, and then with»»nrater. These 19*4 parts contain 8*525 parts of phosphorus. Cast iron sometimes contains calcium and barium, which may be detected by their well-known reagents, oxalate of ammonia, and sulphuric acid. In malleable iron they are seldom or never present. The charcoal found in the residuum of the nitro-muriatic solution is to be burned away under a muffle. The solution itself contains along with the oxyde of iron, protoxyde of manganese, and other oxydes, as well as the earths, and the phosphoric and arsenic acids. Tartaric acid is to be added to it, till no precipitate be formed by supersaturation with caustic ammonia. The ammoniacal liquor must be treated with hydrosulphuret of ammo- nia as long as it is clouded, then thrown upon a filter. The precipitate is usually very voluminous, and must be well washed. The liquor which passes through is to be satu- rated with muriatic acid, to decompose all the sulphurets. The solution still contains all the earths and the oxyde of titanium, besides the phos- phoric acid. It is to be evaporated to dryness, whereby the ammonia is expelled, and the carbonaceous residuum must be burned under a muffle. If the iron contains much phosphorus, the ashes are strongly agglutinated. They are to be fused as already described along with carbonate of potash, and the mass is to be treated with boiling water. The residuum may be examined for silica, lime, barytes, and oxyde of titanium. Muriatic acid being digested on it, then evaporated to dryness, and the residuum treated* with water, will leave the silica. Caustic ammonia, poured into the solution, will sepa- rate the alumina, if any be present, and the oxyde of titanium ; but the former almost never occurs. Manganese is best sought for by a distinct operation. The iron must be dissolved at the heat of boiling water, in nitro-muriatic acid ; and the solution, when very cold, is to be treated with small successive doses of solution of carbonate of am- monia. If the iron has been oxydized to a maximum, and if the liquor has been sufficiently acid, and diluted with water, it will retain the whole of the manganese. This process is as good as that by succinate of ammonia, which requires'' many precautions. ' The liquor is often tinged yellow by carbon, after it has ceased to contain a single trace of iron oxyde. As soon as litmus paper begins to be blued by carbonate of ammonia, we should stop adding it ; immediately throw the whole upon a filter, and wash continuously with cold water. What passes through is to be neutralized with muriatic acid, and con- centrated by evaporation. It may contain, besides manganese, some lime or barjtes. It should therefore be precipitated with hydro-sulphuret of ammonia, the hydrosulphuret of manganese should be collected, dissolved in strong muriatic acid, filtered, and treated, at a boiling heat, with carbonate of potash. The precipitate, weU washed and calcined, contains, m 100 parts, 72-75 parts of metallic manganese. The copper, arsenic, lead, tin, bismuth, antimony, or silver, are best separated by a stream of sulphureted hydrogen gas passed through the solution in nitro-muriatic acid, after it is largely dUuted with water. The precipitate must be cautioudy roasted in a porcelain test, to bum away the large quantity of sulphur which is deposittd in con- sequence of the conversion of the peroxyde of iron into the protoxyde. If nothing remains upon the test, none of these metals is present. If a residuum be obtained, it must be dissolved in nitro-muriatic acid, and subjected to examination. But, in fact, carbon, sulphur, phosphorus, silicon, and manganese, are the chief contaminators of iron* Chloride of silver aflfords the means of determining the proportion of carbon contained in iron and of ascertaining the state in which that substance exists in the metal. Fused 1096 IRON. I chloride of a pale yellow color must be employed. The operation is to be performed in c^se vessels, with the addition of a great deal of water, and a few drops of muriatic acid. The carbonaceous residuum is occasionally slightly acted upon. We may judge of this circumstance by the gases disengaged, as weU as by the appearance of the charcoal. Ductile iron and soft steel, as weU as white cast-iron which has been rendered gray by roasting, when decomposed by chloride of silver, afford a blackish-brown unmagnetic charcoal, and a plumbaginous substance perfectly similar to what is extracted from the same kinds of iron, by solution in acids. A portion of this plumbago is also converted into charcoal of a blackish brown color, by the action of the chloride. Hence this agent does not afford the means of obtaining what has been called the poly-carburet, till it has produced a previous decomposition. But we obtain it, in this manner, purer and in greater quantity than we could by dissolving the metal in the acids. The only subject of regret is, that we possess no good criterion for judging of the progress of this analytical operation. Gray cast iron leaves, besides the poly-carburet, a residuum of plumbago, and carbon which was not chemically combined with the iron ; while tempered steel and white cast iron afford merely a blackish brown charcoal ; but the operation is extremely slow with the latter two bodies, because a layer of charcoal forms upon the surface, which%ob- strucls their oxydizement. For this reason the white cast iron ought to be previously changed into gray by fusion in a crucible lined with charcoal, before being subjected to the chloride of silver; if this process be emfloyed for tempered steel, the combined carbon becomes merely a poly-carburet. It would not be possible to operate upon more than 15 grains, which require from 60 to 80 times that quaniity of the chloride, and a period of 15 days for the experiment. The residuum, which is separable from the silver only by mechanical means, should be dried a long time at the heat of boUing water. It contains almost always iron and silica. After its weight is ascertained, it is to be burned in a crucible of platinum till the ashes no longer change their color, and are not attractable by the magnet. The difference be- tween the weights of the dried and calcined residuum is the weight of the charcoal. The oxyde of iron is afterwards separated from the silica by muriatic acid. In operating upon gray cast iron, we should ascertain separately the proportion of graphite or plumbaso, and that of the combined charcoal. To determine the former, we dissolve a second quantity of the cast iron in nitric acid, with a little muriatic ; the residuum, which is graphite, is separated from the silica and the combined carbon by the action of caustic potash. After being washed and dried, it must be weighed. The weight of the graphite obtained being deducted from the quantity of carbon resulting from the de composition effected by the chloride of silver, the remainder is the amount of the chemi ei^Jy combined carbon. By employing muriatic acid, we could dissipate at once the combined carbon ; but tK method would be inexact, because the hydrogen disengaged would carry off a portion of the graphite. According to Karsten, Mushet's table of the quantities of carbon contained in different steels and cast irons is altogether erroneous. It gives no explanation why, with equal proportions of charcoal, cast iron constitutes at one time a gray, soft, granular metal, and at another, a white, hard, brittle metal in lamellar facets. The incorrectness of Mushet's statement becomes most manifest when we see the white lamellar ca^t iron melted in a crucible lined with charcoal, take no increase of weight, while the gray cast iron treated in the same way becomes considerably heavier. Analysis has never detected a trace of carbon unaltered or of graphite in white cast iron, if it did not proceed from small quantities of the gray mixed with it ; while perfect gray cast iron affords always a much smaller quantity of carbon altered by combination, and a much greater quantity of graphite. Neither kind of cast iron, however, betrays the pres- ence of any oxygen. Steel affords merely altered carbon, without graphite ; the same thing holds true of malleable iron ; while the iron obtained by fusion with 25 per cent, of scales of iron contains no carbon at all. The graphite of cast iron is obtained in scales of a metallic aspect, whereas the com- bined carbon is obtained in a fine powder. When the white cast iron has been roasted, and become gray, and is as malleable as the softest gray cast iron, it still affords no gra« phite as the latter does, though in appearance both are alike. Yet in their properties they are stiU essentially dissimilar. With 4 J per cent, of carbon, the white cast iron preserves its lameUar texture ; but with less carbon, it becomes granular and of a gray color, growing paler as the dose of carbon is diminished, while the metal, after passing through an indefinite numbef of gradations, becomes steely cast iron, very hard steel, soft steel, and steely wrought iron. The steels of the forge and the cast steels examined by Karsten, afforded him fion: X 4 IRON. 1097 2*'^ to ll per cent, of carbon; in the steel of cementation (blistered steel), he never found above If of carbon. Some wrought irons which ought to contain no charcoal, hold as much as J per cent, and'they then approach to steel in nature. The softest and purest xons contain still 0*2 per cent, of carbon. The quantity of graphite which gray cast-iron contains, varies, according to Karsten's experiments, from 2*57 to 3*75 per cent. ; but it contains, besides, some carbon in a state of alteration. The total contents in carbon varied from 3* 15 to 4*65 per cent. When the congelation of melted iron is very slow, the carbon separates, probably in conse- quence of its crystallizing force, so as to form a gray cast-iron replete with plumbago. If the gray do not contain more charcoal than the white from which it has been formed, and if it contain the charcoal in the state of mechanical mixture, then it can have little or none in a state of combination, even much less than what some steels contain. Hence we can account for some of its peculiarities in reference to white cast-iron ; such as its granular texture, its moderate hardness, the length of time it requires to receive anneal- ing colors, the modifications it experiences by contact of air at elevated temperatuies, the high degree of heat requisite to fuse it, its liquidity, and finally its tendency to rust by porosity, much faster than the white cast-iron. We thus see that carbon may combine with iron in several manners ; that the gray cast-iron is a mixture of steely iron and plumbago ; that the white, rendered gray and soft by roasting, is a compound of steely iron and a carburet of iion, in which the carbon pre- dominates ; and that untempered steel is in the same predicament. For the following analyses of cast-irons, we are indebted to MM. Gay Lussac and Wilson, Table. — ^In 100 parts. Cast-iron. Iron. Carbon. Silica. Phos- phorus. Manga- nese. Remarks. White cast from Siegen 94-338 2-690 0-230 0-162 2-590 By wood charcoal. Do. Coblentz - 94-654 2-441 0-230 0-185 2-490 do. Do. a. d. Champ 96-133 2-324 0-840# 0-703 a trace do. Do. Isere - - 94-687 2-636 0-260 0-280 2-137 do. Gray Nivemais - 95-673 2-254 1-030 1-043 a trace do. Do. Berry - - 95-573 2-319 1-920 0-188 do. Mixt'e of coke & do. Do. a. d. Champ 95-971 2-100 1-060 0-869 do. Charcoal. Do. Creusot 93-385 2-021 3-490 0-604 do. Coke. Do. a. d. Franche t Comte - 95-689 2-800 1-160 0-351 do. do. Do. Wales - - 94-842 1-666 3-000 0-492 do. do. Do. Do. - - - 95-310 2-550 1-200 0-440 do. do. 1 Do. Do. - - - 95-150 2-450 1-620 0-780 do. do. Karsten has given the following results as to carbon, in 100 parts of gray cast-iron. 1 Combined Free Total. Gray cast-iron. carbon. carbon. carbon. Remarks. Sicgen, from brown iron stone - 0-89 3-71 4-60 By wood charcoal. Siegen ( Widderstein), from brown and sparry iron - - - - - 1-03 3-62 4-65 do. 1 Malapane, from spherosiderite - 0-75 3-15 3-90 do. Konigshutte, from brown ore - 0-58 2-57 3-15 coke. j_po. at a lower smelting heat - - 0-95 2-70 3'65 do. IRON, Cast, Strength of. — In the following Table each bar is reduced to exactly one equiire incli ; and the transverse strength, which may be taken as a criterion of the vahie of each iron, is obtained from a mean between the experiments upon it, {Memoirs of Brit. Ass.) first on bars 4 ft. 6 in. between the supports, and next on those of half the length, or 2 ft. 3 in. between the supports. All the other results are deduced from the 4 ft. 6 in. bars. In all ca.ses the weights were laid on the middle of the bar. 1098 IRON. Table of Results obtained from Experiments on the Strength and other Properties of Cast Iron, from the principal Iron Works in the United Kingdom. By Mr. Wnu Fairbairn. 1-f Names of Irons 1 2 3 4 A 6 7 8 9 10 11 I'i 13 14 15 16 17 18 19 30 21 22 23 24 35 36 37 38 29 30 31 33 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 Ponkey, No. 3. Cold Blast - - Devon, No. 3. Hot Blast* - - Oldberry, No. 3. Hot Blast - Carron, No. a Hot Blast* • Beaufort, No. 3. Hot Blast - - - Butterley Bute, No. 1. Cold Blast - - - Wind Mill End, No. 2. Cold Blast Old Park, No. 2. Cold Blast - Beaufort, No. 3. Hot Blast - - Low Moor, No. 3. Cold Blast - - Buttery, No. 1. Cold Blast* - - Brimbo, No. 2. Cold Bl;wt - - - Apedale, No. 2. Hot Blast - - Oldberry, No. 2. Cold Blast - - Pentvryn, No. 3. Maesteg, No. 3. Muirkirk, No. 1. Cold Bla-st* Adelphi, No. 2. Cold Blast . - Blania, No. 3. Cold Blast DeTon, No. 3. Cold Blast* - Gartsberrie, No. 3. Hot Blast - Fruod, No. 2. Cold Blast - ■ Lane End. No. 3. Carron, No. 3. Cold Blast* - • Dundivan, No. 3. Cold Blast ■ Maesteg (Marked Red) - - ■ Corbyns Hall, No. 2. ... Pontvpool, No. 3. Wallbrook, No. 3. .... Milton, No. 3. Hot Blast . - Buflerj', No. 1. Hot Blast* Level, No. 1. Hot Blast - - . Pant, No. 2. Level, No. 3. Hot Blast - - ■ W. S. S., No. 3. Kagle Foundry, No. 2. Hot Blast Elsit.ar, No. 3. Cold Bla.« - - Varteg, No. 2. Hot Blast - • • Coltham, No. 1. Hot Blast • - Carroll, No. 3 Cold Blast - . - Muirkirk, No. 1. Hot Blast* • . Bierley, No. 3. Coed-Talon, No. 2. Hot Blast* - Coed-Talon, No. 2. Cold Blast* Monkland, No. 3. Hot Blast - - Ley's Works, No. 1. Hot Blast • Milton, No. 1. Hot Blast - - • Plaskyoaston, No. 2. Hot Blast - •c u ■- £ o o S |2 |E 3 SB It 0) CO 7-122 7-251 7-39 7-0:W 7-038 7-113 7im) 7-1.59 7-2«.'> 7-017 70:n 7-028 7-0!M "■0«7 7-(m 7-007 7 0S0 6-979 7-051 6-;^9« 7-OSO 6-975 7-031 7-041 7-038 6-;«S 7-007 7-1-28 7-069 6-9M 7-ia5 6-969 6-9.55 6-916 6-957 6-976 6-916 ■HI 2 « t> JS .e « i.« <- S ^ m a O -a a a o — — • 17211000 2247:}6.50 2273:)400 17873100 16802000 1.5.379500 1516.3(XX) 16490000 14607000 16.301000 14509500 1.5381200 14911666 148.52000 14307.500 15193000 1.3959600 140035.50 13815,500 14281466 226 ia534a)0 13971,500 13845866 131:16500 l,5.3'.M7(-rf> 15852.500 13730500 1*4V2500 15-280900 1.5241000 149.5.3333 142U000 12.58fi.50(J iriOliOOO 1.55100W 1703600f» 1321M400 161.56133 14322.500 14.304000 122.59rflO 11.539333 11974.500 13.3416.%3 e -^ 2 a; M 9 - o i e e cj .y - - i- ;o5 io-cS 567 .537 ,543 .520 ,505 489 495 483 441 478 462 463 466 457 453 4.38 453 443 441 433 448 427 460 444 4+4 456 440 4:M 4.39 432 427 4-36 461 408 419 413 408 446 422 464 430 417 404 409 403 402 392 3.53 373 695 517 5.34 529 515 487 495 5-29 470 483 4.53 4.55 457 473 4,55 464 457 464 467 434 443 4.30 444 454 441 449 449 403 455 439 446 446 408 430 385 408 419 4.32 424 418 401 386 337 90 S "s e C0 J3 a •a . — y ■3 2 2,' 581 5.37 .5.30 627 617 502 491 +S9 485 474 472 463 4.59 4.56 455 o a U « O Q ft. 5 a 1-747 1-09 1-005 1-365 1-599 1-815 1-764 1-.581 1-621 1-612 1-.S52 1-.55 1-748 1-730 1-811 455' 1-484 4.54 4.53 449 448 448 447 447 444 443 443 442 443 440 440 438 436 432 431 429 429 427 4-27 426 424 419 418 418 416 413 403 393 369 a57 1-957 1-734 1-759 1-726 -790 1-557 1-825 1-414 1-336 1-469 1-887 1-687 1-857 1-443 1-368 1-64 1-.516 1-151 1-358 1-339 1-.512 2-224 1-4.50 1-532 1-331 1-570 1 -2i-2 1-882 1-470 1-762 1-890 1-.525 1-366 Color. 993 Whitish gray .589 While - • 649 White - • 710 Whitish gray 807 Dullish gray 889 Dark gray - 872 Bluish gray 765 Dark giay - 718 Gray - - - 729 Dull gray - 8.55 Dark gray . 721 Gray - . - 815 Light gray - 791 Light gray - 822 Dark gray - 650 Bluish gray 886 Dark gray - 770 Bright gray 777 Light gray - 747 Bright gray 7.53 Light gray 998 Light gray - 841 j Light gray - 629 Dark gray - 6931 Gray - - - 6741 Dull gray - 8.30' Bluish gray 727iGray - - . 816 Dull blue - 625! Light gray - 686 Gray - - Dull graj- - Light gray - Light gray . Dull gray - Light gray - Bluish gray Gray - ~ Gray - - - Whitish gray Gray . . - Bluish gray Dark gray - Bright gray Gray - - - Bluish gray Bluish gray Gray ... Light gray 721 69i» 611 670 6,54 618 992 621 716 5-30 656 494 771 600 709 742 638 617 Quality. Hard. Hard. Hud. Hard. Hard. Soil. Soft. Hard. Soft. Hard. Soft. Hather hard. Kather hard. Stiff. Kather soft. Hard. Rather soft. Fluid. Soft. Hard. Hard. Soft. Open. Soft. Soft. Rather soft. Fluid. Soft. Rather soft. Rather hard. Rather hard. Soft. Sort. Rather bard. Soft. Soft. Soft. Soft. Hard. Rather soft. Hard. Soft. Soft. Soft. Rather soft. Soft. Soft. Soft and finid. Ratlier soft. Rule. — To find from the above table the breakin^^ weight in rectangular bars, gene- rally, calling b and d the breadth and depth in inches, and / ihe di-*tance between the supports in feet, and putting 4-5 for 4 ft. 6 in., we have 4-5x^25 = breaking weight in lbs., the value of S being taken from the table above. For example : — What weight would be necessary to break a bar of Low Moor iion, 2 inches broad, 3 inches deep, and 6 feel oetween the supports ? According to Analyses of Ten Specimens of Cast Iron made from South Staffordshire Iron Ore, Wegt of Dudley. Iron Jrom Hot Blast. Iron I. II. III. IV. V. VI. 89.53 92-93 93-84 92-90 C(a)95-23 95-80 Carbon - - - - Carbon - - - - C8-27 7-93 C3-11 6-61 C2-93 5-64 C0-S7 6-88 C(b) 1-77 0-49 2-72 0-26 Silica, Ac - - - . . - - ... - . . 0-81 0.11 Man^ranese - - - 1-71 1-80 0-72 0-62 0-84 0-M Calcium - - - 0-11 trace 0.34 0-06 010 0-06 Sodium - - - 0-41 0.37 0.39 0-30 0-19 0-14 Potassium - - - ... . trace trace Sulphur - 0-07 trace minute trace trace trace trace Phosphorus - • i ! 0-54 lost 0-07 0-40 0-12 0-87 100-39 100-19 100 90 101.11 98-55 100-00 * The irons with asterisks are taken from the experiments on hot and cold blast iron, made by Mr. Hodgkinson and myself for the British Association for the Advancement of Science.— Se^ Seventh Report, voL vL tThe modulus of elasticity was nsnallv taken from the deflection caused bv 112 lbs. on the 4 ft, in. bars. i I IRON. Iron from Cold Blast. 1099 Iron- ------ Combined carbon (a) - Uncombined carbon (b) Silica Manganese - - - - Cobalt Chromium- - - - . Calcium Sodium Potassium Sulphur Phosphorus - - - . I. 94-10 1-87 1-92 1-30 112 trace trace 006 015 trace trace 0-21 100-73 III. 96-57 trace trace 042 0-11 0-36 101-75 n. . V. 94-&S 94-42 C 1-98 3-71 C2-73 4.05 0-.33 - 094 trace 0-25 0-30 016 034 0-05 003 - trace 0-36 99-20 - 100-27 the rule given above, we have 6 = 2 inches, d=3 inches, / = 6 feet, 5 = 472 from the „„ 4-5 Xbd'S 4-5 X 2 X 32 X 472 table. Ihen ^ = = 6372 lbs., the breaking weight A very small amount of phosphorus is found to impart to iron a great degree of brittleness, when bar iron contains but 0*5 per cent. Fig. 818. represents in section, andfig. 817. in plan, the famous cupola furnace for cast- ing iron employed at the Royal Foundry in Berlin. It rests upon a foundation a, from IB to 24 inches high, which supports the basement plate of cast iron, furnished with ledges, for binding the lower ends of the upright side plates or cylinder, e. Near the mouth there is a top-plate d, made in several pieces, which serves to bind the sides at their upper end, as also to cover in the walls of the shaft. These plates are most readily se- cured in their places by screws and bolts. Within this iron case, at a little distance from it. the proper furnace-shaft c, is built with fire-bricks, and the space between this and the iron is filled up with ashes. The sole of the hearth /, over the basement-plate, is composed of a mixture of fire-clay and quartz-sand firmly beat down to the thicknew of 6 or 8 inches, with a slight slope towards the discharge-hole for running off the metal, g is the form or the tuydre (there are sometimes one on each side) ; h the nose pipe; the discharge aperture i is 12 inches wide and 15 inches high; acrosa which the sole of the hearth is rammed down. During the melting operation this opening is filled up with fire-clay ; when it is completed, a small hole merely is pierced through it at the lowest point, for running off the liquid metal. The hollow shaft should 818 be somewhat wider at bottom than at top. Its dimensions vary with the magnitude of the foundry. When 5 feet high, its width at the level of the tuyere or blast hole may be from 20 to 22 inches. From 250 to 300 cubic feet of air per minute are required for tlie working of such a cupola. For running down 100 pounds of iron, after the furnace has been brought to its heat, 48 pounds of ordinary coke are used ; but with the hot blast much less will suffice. The furnace requires feeding with alternate charges of coke and iron every 8 or 10 minutes. Tlie waste of iron by oxidation and »lag amounts in most foundries to fully 5 per cent. For carrying off the burnt air, a chim- ney-hood is commonly erected over the cupola. See Foundry. 1100 IRON. The double arche«l air or wind-furnace used in the foundries in StaflFordshire for meltinif cast iron, has been found advantageous in saving fuel, and preventing waste bv sla-r It requires fire-bricks of great size and the best composition. " ^ The main central key-stone is constructed of large fire-bricks made on purpose ; ao-ainst that key-stone the two arches press, having their abutments at the sides against the walla. The highest point of the roof is only 8 inches above the melted metal. The sole of the hearth is composed of a layer of sand 8 inches thick, resting upon a bed of iron or of brickwork. The edge of the fire-bridge is only 3 inches above the fluid iron In from 2 to 4 hours from 1 to 3 tons of metal raav be founded iR such a furnace according to its size; but it ought always to be heated'to whiteness before the iron is uitroduced 100 pounds of cast iron require from 1 to U cubic foot of coal to melt them Ihe waste varies from 5 to 9 per cent, I shall conclude the subject of iron with a few miscellaneous observations and statist!- cal tables. Previously to the discovery by Mr. Cort, in 1785, of the methods of puddling and rolhng or shingling iron, this country imported 70,000 tons of this metal from Kussia and Sweden ; an enormous quantity for the time, if we consider that the cotton and other automatic manufactures, which now consume so vast a quantity of iron were then m their infancy. From the following table of tlie prices of bar iron in succe*. «ive years, we may infer the successive rates of improvement and economy, with slight Years. Per Ton. £ 9. £ 8. 1824 9 to 10 1825 10 0—14 1826 8 10 — 10 1827 8 9 1828 8 10— 8 1829 6 10— 7 Years. 1830 1831 1832 1833 1834 1835 Per Ton. £ «. £ «. 5 5 to 6 6 5 — 6 10 5 — 6 10 5 10 — 6 6 — 6 10 5 10 — 7 The export of iron m 1836, in bars, rods, pigs, castings, wire, anchors, hoops, nails and old iron amounted to 189,390 tons ; in unwrought steel to 3,014, and in cutlery to 21 072 • in whole to 213,478; leaving apparently for internal consumption 776,522 tons, 'from' which however one-tenth should probably be deducted for waste, in the conversion of the bar iron. Hence 700 000 tons may be taken as the approximate quantity of iron made use of m the United Kingdom, in the year 1836. ^ J The years 1835 and 1836 being those of the raUway mania over the world produced ft considerable temporary rise in the price of bar iron ; but as this increased demand caused the construction of a great many more smelting and refining furnaces, it has tended eventually to lower the prices; an eflfect also to be ascribed to the more general use of the hot blast. ^ The exports of foreign produce in 1850 amounted to 5,996 tons, in 1851 to 4 818 ^nlf^J .-^"^"^I", P^^V''^ f """ ^'""^^ (^'^^^P^ ^*^^^) ^" 1S50' 772,830 tons, in 1861 908,955 tons; the declared value being respectively 4,956,308^. and 5 4141oi; The imports in bars unwrought amounted in 1850 to 34,066 tons, and in 185l'to 4o"''>79 The relative cost of making cast iron at Merthyr Tydvil in South Wale^ and at Glasgow, was as follows, eight or nine years ago. At Merthyr. ^ » Tons. Cvts. Qrs. Raw mine at 10 per ton, 3 7 0- Coal at 6 2 16 - Limestone 15 2- Other charges - - . . . . ". Total Cost «. d. 6 5 3 Raw mine at 4 Splint coal at 2 Limestone at Coals for the engine Other charges Total Coet At Glasgow. Tons. Cwts. 3 10 5 16 14 1 10 £ «. d - 1 13 6 - 16 6 - 1 4 - 9 1 - S 6 £ «. d. - 16 3 - 14 - 3 6 - 3 - 1 1 2 17 9 IRON. 1101 L 1 The cost is still nearly the same at Merthyr, but it has been greatly decreased at Glasgow. The saving of fuel by the hot-blast is said to be in fact so great, that blowing cylinders, which were adequate merely to work three furnaces at the first period, were competent to work four furnaces at the last period, llie saving of materials has more- over been accompanied by an increase of one-fourth in the quantity of iron, in the same time ; as a furnace which turned out only 60 tons a week with the cold blast now turn:* out no less than 80 tons. Tliat the iron so made is no worse, but probably better, when jiKlicioualy smelted, would appear from the following statement. A considerable order was not long since given to four iron-work companies in England, to supply pipes to one of the London water companies. Three of these supplied pipes made from the cold-blast iron ; the fo.urth, it is said, supplied pipes made with the hot-blast iron. On subjecting these several sets of pipes to the requisite trials by hydraulic pressure, the last lot was found to stand the proof far better than any of the former three. — That iron was made with raw coal. I have been since told by eminent iron-masters of Merthyr, that this statement stands in need of confirmation, or it is probably altogether apocryphal, and that as they find the hot blast weakens the iron, they will not adopt it. Between the cast irons made in different parts of Great Britain, there are character- istic differences. The Stafibrdshire metal runs remarkably fluid, and makes fine sharp castings. The Welsh is strong, less fluent, but produces bar iron of superior quality. The Derbyshire iron also forms excellent castings, and may be worked with care into very good bar iron. The Scotch iron is very valuable for casting into hollow ware-*, as it affords a beautiful smooth skin from the moulds, so remarkable in the castings of the Carron company, in Stirlingshire, and of the Phcenix foundry, at Glasgow. The Shrop- shire iron resembles the Staffordsliire in its good qualities. The average quantity of fine metal obtainable from the forge-pigs at Merthyr Tydvil, from the finery furnace, is one ton for 22 J cwt. of cast iron, with a consumption of about 9 J cwt. of coal per ton. Estimate of ihe average cost of erecting three blastfurnaces. BUILDING £XP£N'SES. Foundations - - - -- - - • • £480 Masonry of hewn grit-stones -...-.- 600 Common bricklayers' work .....-- 1200 Lining of the furnace, hearth, &c., in fire-bricks - - - - - 1140 Fire-clay for building -.--.... 80 Lime and sand --....^.. 800 CAST IRON. Cast-iron pieces, such as dam-plates, tymp-plates, beams, tuyere-plates, Ac., weighing about 24 tons for each furnace; — in whole - - - - 1140 WROUGHT IRON. For the binding-hoops, keys, furnaces. The figures show two sets built together ; the thira set being detached oa account of peculiar local circumstances. The air enters tlie horizontal pipe A, in the ground plan. Jig. 830, on one side of the arched or syphon pipes, shown in upright section inJip.S'Sl, and passes through these pipes to the horizontal pipe, B, on the other side ; whence it proceeds to the blast furnace. These syphon pipes are flattened laterally, their section being a parallelogram, to give more heating surface, and also more depth of pipe (in the vertical plane), so as to make it stronger, and less liable to ► '^" I'^i # IRON. 1111 bend by its own weight when softened by the red heat. This system of arched pipe apparatus is set in a kind of oven, from which the flue is taken out at the top of it ; t)ut it thence again descends, before it reaches the chimney, entering it nearly al the level of the fire grate (as with coal gas retorts). By this contrivance, the nii^es are kept in a bath of ignited air, and not exposed to the corroding influence of a current of flame. The places and directions of these oven flues are plainly markea in th« drawing. Fig, 87 is a plan of the blast furnace, drawn to a smaller «caie than th»- ct th« ©receding figures. lMliihihT|- 5 The three sets of hot-blast apparatus, all communicate with one line of conductmg pipes. A, which leads to the furnace. Thus in case of repairs being required in one set, the other two may be kept in full activity, capable of supplying abundance of hot air to the blast, though of a somewhat lower temperature. See Smelting for con- structions of diff'erent blast furnaces ; also Puddmng. During a visit which I have recently made to Mr. Jessop, at Butterley, I f(»und (hi» I1I2 IRON. eminent and very ingenious iron-master had made several improvements upon nis hot- blast arrangements, whereby he prevented the alteration of form to which the arched pipes were subject at a high temperature, as also that he was about to employ five tuyeres instead of three. For a drawing and explanation of his furnace-feeding apparatus, see Smelting. IRON CAST, improvedhy combination with vrrought iron. This improvement, invented and patented by Mr. Morries Stirling, has been reported upon by the Government Commissioners on the application of iron to railway purposes. It is applicable to both cast and wrought iron. A mixture of the two in certain proportions has the effect of giving a fibrous nature to the cast metal, and thereby greatly increasing its strength and tenacity. For all kinds of beams, girders, and other castings where strength is required, its use is found very advantageous and economical. Beams cast of such toughened iron may be made of less dimensions to support the same load ; and they have the advantage of deflecting to a greater extent, and are therefore not so liable to sudden failure. At page 101. of the Commissioners' Report, an abstract is given of a series of trials, from which it will be seen that Mr. Stirling's alloy is nearly 50 per cent, superior to 16 other sorts of iron experimented upon. Various other experiments have been made by Mr. Owen for the Admiralty, and by Messrs. Rennie and others, all with the same results, showing the increase of strength in the patent iron. Common Scotch pig iron thus toughened can be had now (1851) for about 2/. 10». per ton ; and it is at least 50 per cent stronger than the best Blaenavon iron, which costs 3/. 3s. per ton. The improvements in the manufacture of torought iron are, first, the admixture of a certain alloy in the puddling furnace, by which all malleable iron is rendeied much more fibrous and tougher than common wrought iron, so much so that common or merchant bar becomes equal to best bar, thus saving one process to the manufacturer. Also very ordinary iron, which can scarcely be used at all, is made equal to the best. The 'olio wing abstracts of experiments are given in the Report of Commissioners (p. 417.^ IRON ORES. 1113 V \i »: Breaking Strain in Tons per Square Inch. 23-23 24-47 24-33 27-81 27-70 Average of Mr. Jesse Hartley's experiments at Liverpool on many sorts of malleable iron - - • - - Average of S. C. Crown Iron from numerous trials at Woolwich Dockyard - - . . - - - Average of best Dundy van bar , . . - - Average of Mr. Sterling's best quality . . . - Do. another quality ....-- Tlie cost of the process is only a few shillings per ton. When Mr. Stirling's toughened pig is used in the puddling furnace instead of common pig, and the alloy added, an iron is produced of a very superior quality, of a very fibrous nature, and much finer in the fibre than the iron mentioned above; this will be found very advantageous m the manu- facture of thin plates and sheets. Second, the admixture of a different alloy in the puddling furnace, whereby a quantity of iron is produced quite opposite in its character to the last ; instead of being fibrous, it becomes hard and crystalline, approaching to the nature of steel. The average streno-th of common round bars, 1 inch diameter, is about 3 inches per foot ; whereas the average of Mr. Stirling's hardened iron is from one-eighth to three-eighths q/" au inch per foot . This shows the great stiffness obtained by this method. The crystalline nature of this description of iron causes it to resist compression, lamination, and abrasion. Thus for the top portions of wrought iron girders, it is precisely what is required to resist the compression force, the fibrous iron being used for the bottom portion, to resist the tension. For rails and tyres for wheels this sort of iron is peculiarly adapted ; the top of the rails and the outside of the tyres being made with it. will resist the wear and tear and lamination so universally complained of; and rails made of the patent iron are found to answer remarkably well. They have been used on the East Lancashire, Caledonian, Edinburgh and Glasgow, and other railways, with great success ; the extra cost of rails made of this iron being only from 7«. 6t/. to 10«. per ton. The first of these improvements in the manufacture of metallic sheets is the use of polished rolls to such sheets as are either intended for being coated with other metals, or after such sheets have been bo coated ; and this improvement is more particularly applicable to iron plate either coated or to be coated with tin, zinc, or other of the more fusible metals. After the plates or sheets of iron have been cleaned by pickling or other- wise in the usual way, they are to be passed between polished rollers, using sufficient pressure to smooth the surface without injuring the quality by producing brittleness ; and as iron is of such different qualities as regards its ductility, both when hot and cold (according to the district from whence the ore is produced, and peculiarities of make,) no absolute rule respecting the amount of pressure can be given, but a little practice will enable a workman to judge, and care is to be taken that the rolls are clean. The plates so polished are then to be dipped in the usual manner into the metal or alloy in- tended for the coating. After the plates or sheets have been coated with any metal or allo3^ they are, where a high degree of smoothness is desired, again passed between polished rolls, the degree of pressure being carefully regulated so as to avoid producing brittleness. It is not essential that the sheets of metal should be passed between the smooth rolls before coating, but it is preferred that such should be the case. Ikon Cast, Enamelled. The Great Exhibition contained the following examples. Model of an enamelled tank or cistern composed of cast iron plates, screwed together with gutta percha joint. Model of enamelled water or gas pipes and watercloset pan, with trap pipe ; dry trough, poultry trough, and spittoon. The application of enamel for the protection of water cistern pipes, ecome peroxydized very slowly ; and, in a particular exjjeriment, I found that contact with the air during several hours caused no diminution in the quantity of bichromate of potash required. As the process may be completed in a few minutes, it is certain that no inaccuracy can arise from this cause. It is also important to inquire whether the chromic acid in the chromates of potash may not be partially deoxydized by hydrochloric acid alone without the presence of a protosalt of iron. Such a reaction would obviously give rise to a serious error. It is well known that concentrated hydrochloric acid rapidly decomposes the chromic acid of the chromates when aided by the application of heat. But I have satisfied myself, by numerous experiments, that this acid exerts very little appreciable action upon dilute solutions of the chromates of potash, either cold or warm, and that the action is only partial even after continued ebullition ; so that the present method is free from inaccu- racy on this account. — Dr. Penney. Bronzing of polished iron. — The barrels of fowling-pieces and rifles are occasionally bronzed and varnished, to relieve the eye of the sportsman from the glare of a polished metal, atid to protect the surface from rusting. The liquid used for browning the barrels is made by mixing nitric acid of specific gravity 1.2, with its own weight of spirit of nitric ether, of alcohol, and tincture of muriate of iron ; and adding to that mixture a quantity of sulphate of copper equal in weight to the nitric acid and ethereous spirit taken toge- ther. The sulphate must be dissolved in water before being added ; and the whole being diluted with about 10 times its weight of water, is to be bottled up for use. This liquid must be applied by friction with a rag to the clear barrel, which must then be rubbed with a hard brush ; processes to be alternated two or three times. The barrel should be afterwards dipped in boiling water, rendered feebly alkaline with carbonate of potash or soda, well dried, burnished, and heated slightly for receiving several coats of tin-smith's lacquer, consisting of a solution of shellac in alcohol, coloured with dragon's blood. ISINGLASS, or Fish glue, called in Latin ichthyocolla, is a whitish, dry, tough, semi- transparent substance, twisted into different shapes, often in the form of a lyre, and consisting of membranes rolled together. Good isinglass is unchangeable in the air, has a leathery aspect, and a mawkish taste, nearly insipid ; when steeped in cold water it swells, softens, and separates in membranous laminae. At the boiling heat it dissolves in water, and the solution, on cooling, forms a white jelly, which is semi-transparent, soluble in weak acids, but is precipitated from them by alkalis. It is gelatine nearly pure ; and if not brittle, like other glue, this depends on its fibrous and elastic texture. The whitest and finest is preferred in commerce. Isinglass is prepared from the air- bladders of sturgeons, and especially the great sturgeon, the accipenser huso ; which is fished on the shores of the Caspian Sea, and in the rivers flowing into it, for the sake chiefly of its swim bladder. The preparations of isinglass in this part of Russia, and partictilarly at Astracan, consists in steeping these bladders in water, removing carefully their external coat, and the blood which often covers them, putting them into a hempen bag, squeezing them, softening them between the hands, and twisting them into small cylinders, which are afterwards bent into the shape of a lyre. They are ready for the market immediately after being dried in the sun, and whitened with the fumes of burning sulphur. 1116 ISLAND MOSS. In some districts of Moldavia, another process is followed. The skin, the stomach, the intestines, and the swim bladder of the sturgeon are cut in small pieces, steeped in cold water, and then gently boiled. The jelly thus obtained is spread in thin layers to dry, when it assumes the appearance of parchment. This being softened in a little water, then rolled into cylinders, or extended into plates, coiic*!tutes an inferior article. The swim bladder of the cod and many other fishes also furnishes a species of isin- glass, but it is much more membranous, and less soluble, than that of the sturgeon. The properties of isinglass are the same as those of gelatine or pure glue ; and its uses are very numerous. It is employed in considerable quantities to clarify ale, wine, liqueurs, and coffee. As an article of food to the luxurious in the preparation of creams and jel- lies, it is in great request. Four parts of it convert 100 of water into a tremulous jelly, which is employed to enrich many soups and sauces. It is used along with gum as a dressing to give lustre to ribands and other silk articles. The makers of artificial pearls employ it to fix the essence -d' Orient on the glass globules which form these pearls, and the Turks set their precious stones or jewellery by means of isinglass dissolved in alco- hol along with gum ammoniac ; a combination which is also employed in this country to join broken pieces of China and glass, under the name of diamond cement. That setting preserves its transparency after it solidifies, if it be well made. It is by covering taffety or thin silk with a coat of isinglass that court plaster is made. A solution of isinglass colored with carmine forms an excellent injection liquor to. the anatomist. M. Rochen has made another pretty application of isinglass. He plunges into a limpid solution of it, made by means of a water bath, sheets of wire gauze set in window or lamp frames, which, when cold, have the appearance of glass, and answer in- stead of it for shades and other purposes. If one dip be not sufficient to make a proper transparent plate of isinglass, several may be given in succession, allowing each film to harden in the interval between the dips. The outer surface should be varnished to pro- tect it from damp air. These panes of gelatine are now generally used for lamps instead of horn, in the maritime arsenals of France, Isinglass imported for home consumption, and duties paid, in 1835. 1836. 1835. 1836. 1,814 cwts. I 1,735 cwts. | £4Ji90 | £4,125 ISLAND MOSS (Lichen d'Islande, Fr. ; Flechte IsL, Germ.) is a lichen, the Cetraria islandica, which contains a substance soluble in hot water, but forming a jelly when it cools, styled lichenine by M. Guerin. Lichenine has a yellowish tint in the dry state, is transparent in thin plates, insipid, inodorous, and difiicult to pulverize. Cold water makes it swell, but does not dissolve it. It is precipitated in white flocks by alcohol and ether. Iodine tinges it of a brownish-green. Sulphuric acid converts it into sugar ; and the nitric into oxalic acid. Lichenine is prepared by extracting first of all from the plant a bitter coloring matter, by digesting 1 pound of it in 16 pounds of cold water, containing 1 ounce of pearlash ; then draining the lichen, edulcorating with cold water, and boiling it in 9 pounds of boiling water till 3 pounds be evaporated. The jelly which forms, upon cooling the filtered solution, is dark colored, but, being dried and redissolved in hot water, it becomes clear and colorless. Lichenine consists of 39-33 carbon, 7*24 hydrogen, and 55-43 oxygen. With potash, lime, oxyde of lead, and tincture of galls, the habitudes of lichenine and starch are the same. The mucilage of island moss is preferred in Ger- many to common paste for dressing the warp of webs in the loom, because it remains soft, from its hygrometric quality. It is also mixed with the pulp for sizing paper in the vat. IVORY (Ivoire, Fr. ; Elfeitbein, Germ.) is the osseous matter of the tusks and teeth of the elephant, the hippopotamus, or morse, wild boar, several species ot phocee, as well as the horn or tooth of the narwhal. Ivory is a white, fine-grained, dense suh- stance, of considerable elasticity, in thin plates, and more transparent than paper of equal thickness. The outside of the tusk is covered by the cortical part, wliich is softer and less compact than the interior substance, with the exception of the brown plate that sometimes lines the interior cavity. The hardest, toughest, whitest, and most translucent ivory, has the preference in the market ; and the tusks of the sea-horse are considered to afford the best. In these, a rough glassy enamel covers the cortical part, of such hardness, as to strike sparks with steel. The horn of the narwhal is sometimes ten foet long, and consists of an ivory of the finest description, as hard as that of the elephant, and susceptible of a better polish ; but it is not in general so much esteemed as the latter. Ivory has the same constituents as the teeth of animal?, three fourths being phosphate, irith a little carbonate of lime ; one fourth cartilage. See Bones. It is extensively employed by miniature painters for their tablets; by turners, in making numberless useful and ornamental objects ; by cutlers, for the handles of knives and forks ; by comb-makers ; as also by philosophical instrument makers, for constructing IVORF. 1117 the scales of thermometers, &c. The ivory of the sea-horse is preferred by aentists for makmg artificial teeth; that of the East India elephant is better than of the African. V\ hen It shows cracks or fissures in its substance, and when a spUnter bioken off has a duU aspect, it is reckoned of inferior value. Ivory is distinguishable from bone by its peculiar semi-transparent rhombohedral net-work, which may be readily seen in slips of ivory cut transversely. ^ l?""* i^ JV "^^u.^" *^^^ ^ yellow-brown tint by exposure to air. It may be whitened or bleached, by rubbing it first with pounded pumice-stone^nd water, then placing it moist under a glass shade luted to the sole at the bottom, and exposing it to sunshine. The sunbeams without the shade would be apt to occasion fissures in the ivory The moist rubbing and exposure may be repeated several times. For etching ivory, a ground made by the foUowing recipe is to be applied to the polish- t u »? "7^^^^ °^ pure white wax, and transparent tears of mastic, each one ounce ; asphalt, half an ounce. The mastic and asphalt having been separately reduced to fine powder, and the wax being melted in an earthenware vessel over the fire, the mastic is to be first slowly strewed in and dissolved by stirring; and then the asphalt in like man- hftK |'"S/?°;P«'i';d AS to be poured out into lukewarm water, well kneaded, as it cools, by the hand, into rolls or balls about one inch in diameter. These should be kept wrap- C?i 1 '^^^7^^^ ^f^^l' , If ^hite rosin be substituted for the mastic, a cheaper composition will be obtained, which answers nearly as weU ; 2 oz. asphalt, 1 oz. rosin, | oz. white ^^vintTln'T f oportio'^s. Callot's etching ground for copper plates, is made by dis- f^rn^i ^^^V^:,?^ "?^?'^ '" ^ °^- ^f ^^"T^ ^""^ li^s^^d oil ; filtering the varnish through a rag, and bottling it for use. in^^^^V °V!l^ ^^« fi^< grp^'ids being applied to the ivory, the figured design is urfoc. if fn i '^"^ '' '"^ f^ ^t"""^ ^^y' ^ ^^^?« °f ^^^ is to be applied, and the with ?L •? / ^\Z T^'^^ "^^i^ '^""^^^ sulphuric acid. The effect comes better out tTon nV m?;^ t ^ ^"^^ ^^^^ ' """"^^^ '^P^*^^'^^ ^^^^ ^^^^^^ ^^ it becomes dilute by absorb Ti^lT f\^'^^ concentrated oil of vitriol. Simple wax may be employed instead of the copperplate engraver's ground ; and strong muriatic acid instead of sulphuric. If an acid solution of silver or gold be used for etching, the design will become purple or Ac7d C«'tf n'r -f '"^ 'T^''\ ^^^ ^^^ °^"y ^^ -^^'^^ ^^^^y ^ith oil of tu?^ntine Acid nitrate of silver affords the easiest means of tracing permanent black lines upon Ivogr may be dyed by using the following prescriptions :- nW.;* r ^"'^ ^^^.'J'''^'^^ ^^^^ f"^ ^^^^^al hours in a dUute solution of neutral mtiate of pure silver, with access of light, it will assume a black color havhi<^ a Sic^hUv ^reen cast A stiU finer and deeper black may be obtained by iK^innV he iW f^^^^^^^ Tre^aLfaTe^on^oT'"' "' ''="'"'' ''^' ''^'^ ^^^^^^^^^^ " ^^ ^ '''^'''- ^^ ^^ -lp"^« ».nn*J^'*'/f T^^^l.''''"^' i' ^^Pt immersed for a longer or shorter time in a dilute solu- or ?esf infenX'. '" ^'""' ""'"^'"^ ^''' ^'^'^^^ '' ^^""^^^ "^ blurtint of^ea^^^^^ 3. Green dye.— Jhh is given by dipping blued ivory for a Uttle while in solution of aitro-muriate of tin, and then in a hot decoction of fustic solution ol th^n nTf^r ^^'-l^ ^ir"; ^^ impregnating the ivory first with the above tin mordant and then digesting ,t with heat in a strained decoction of fustic. The color na^L ,n^^ orange, if some Brazil wood has been mixed with the fustic. A ve^ finTunE4ISk nf hrn"""; ^" ^^''^^^^i^^/^d to ivory by steeping it 18 or 24 hou,^\ rstrnXluUon Liun^fnf ,tt7f1f .^ given by imbuing the ivory first with the tin mordant, then hi ?£ ? •. f-,^*^ "^ ^7^'^ ^"""^^ cochmeal, or a mixture of the two. Lac-dye ma>- n?nn!^H 72 r.J ^""'^ advantage, to produce a scarlet tint. If the scarlet ivory ^ plunged for a little in a solution of potash, it will become cherry red. «1mrf f! -^f"", ?1^^" i".t'^e l%'W"od bath, to ivory previously mordanted for a short time with soluti.m of tin. When the bath becomes exhausted, it imparts a lilac Linin/J W TP '«/h«"ged to purple-red by steeping it a little while in water con- taining a few drops of nitro-munatic acid. hnfYnr' w^*''*!i**' ^^^?^ iyory, it may in general be observed, that the colours penetrate better before he surface is poh.hed than aferwards. Should any dark spotTappear they may be cleared up by rubbing them with chalk ; after which the ivory should b^ dyed once more to produce perfect uniformity of slvad*. / On fakiirg ii i>at.of-the boili..,.. hot dye bath it ought to be immediately plunged into.cold waiter, to m event liie ^ha^5 of fissures being caused by the heat. '.••.'.,' z*^' - • .'^ ."'r'.'-V a If the borings and chips of the ivory-turner, caWed ivory dust, be boiled in water kind of fine size 18 obtained. '..'.': .\ •■•..... * • • • • - ' • i , ' ' ; .' ■ • t 1118 IVORY BLACK. The importation of elephants' teeth amounts to about 5000 cwts, per annum. Ivory made flexible. Ivory articles may be made flexible and semi-transparent, bf immersing them in a solution of pure phosphoric acid of sp. gr. 1,130, and leaving them there till they lose their opacity ; they are then to be taken out, washed with water, and dried with a soft cloth ; it thus becomes as flexible as leather. It hardens on exposure to dry air, but resumes its pliancy wlien immersed in hot water. Necks of children's sucking bottles are thus made. IVORY BLACK {Noir cTivoire, Fr. ; Kohle vo7i El/enbein, Germ.) is prepared from ivory dust, by calcination in the very same way as is described undfer Bonk Black. The calcined matter being ground and levigated on a porphyry slab affords a beau- tiful velvety black, much used in copperplate printing. Ivory black may be prepared upon the small scale by a well regulated ignition of the ivory dust in a covered crucible. END OF THE FIRST VOLUME. 1-i • . . » » I m » c » «. ' , ' • ' :iRCI3LATEg FOR 1 WEE2 COLUMBIA UNIVERSITY LIBRARIES This book is due on the date indicated below, or at the expiration of a definite period after the date of borrowing, as provided by the library rules or by special arrangement with the Librarian in charge. DATE BORROWED DATE DUE DATE BORROWED DATE DUE j • '. " \ 1 1 1 i C28 (747) Mice • ♦ 2 S1S94 /^M Oi'^lj ^IMo Oicc^ CIRCuLai .^o FOii 1 V^ -M M«fi \^ ^*c .C*'*^ -^ i."! f> ^" --.^K -* J % ' - V- "' , --Vf V - ^ --^r?;-- ^^ M' ^» ^i^j^4,-||.S;^l^.|:,^ji;i BIBLIOGRAPHIC IRREGULARITIES MAIN ENTRY: Ure. Andrew A dictionary of arts. manufactures,..V. 2 Bibliographic irregularities in the Original Document: List all volumes and pages affected; include name of institution if filming borrowed text. Page(s) missing/not available: yolume(s) missing/not available:. .Illegible and/or damaged page(s): X Page(s) or volume(s) misnumbered: page 341 numbered 34: pa ge 485 numbered 285 Bound out of sequence: . ^ Page(s) or volume(s) fi from copy borrowed from Other: TRACKING*: MSH04704 ^^i^i 2S '■ ' « I z ir v^ -• ■^ ' '~ ^ \ ? ' r r . ' "f^^'T, , ' : 1 r:^. -r^.' '^^1 ■r- - ^ •• •T-). '■imi ^tf- V^if SL-r"'-' ^K, ^^ ' ^ -«ii|r<-v; 7 ./ ti^ C«r, D\^o UrS mt^fCttp0fBrttif0rk LIBRARY School of Business Given by I / DICTIONARY or AETS, MANUFACTURES, AITD MINES: OONTAININa A CLEAR EXPOSITION" OF THEIR PRINCIPLES AND PRACTICE. BT ANDEEW URE, M.D., F.B.8. M.G.8. M.A.8. LOND. ; M. AOAD. N.8. PHILAD. ; 8. PH. SOO. N. OEBM. HANOV. ; MULH. ETC. ETC. • . J IILUSTEATEO-i^raB-irfiAPLr SIXTEEJf HUHI/RED ENGRAVINGS ON WOOD. ( 1 i » • « .1 A » 1 \ * t « . « • • « * REPRINTED ENTIRE FROM THE LAST CORRECTED AND GREATLY ENLARGED ENGLISH EDITION. IN TWO VOLUMES.- VOL. H. D. NEW-YORK : APPLETON & COMPANY, 846 A 348 BROADWAY. M.DCCC.LIV. / * DICTIONARY or t » >■ • . • t <■ • « • • * *• •♦ ■* % ^ t ' • • • * • ^ » ' • • 1 • t •# » • • • * u • X ARTS, MANUFACTURES, AND MINES. K. KALL The Arabs gave this name to an annual plant which grows near the sea- shore ; now known under the name of salnola soda, and from whose ashes they extracted a substance which they called alkali, for making soap. The term kali is used by Ger- man chemists to denote caustic potash; and kalium, its metallic basis; instead of our potassa and potassium, of preposterous pedigree, being derived from the words pot ashes, that is ashes prepared in a pot. KAOLIN, (Terre d porcelaine, Fr. ; Porzellanerde, Germ.), is the name given by the Chmese to the fine white clay with which they fabricate the biscuit of their porcelains. »ee Clay. Berthier's analyses of two porcelain earths are as follows : Analysea. Silica - - - Alumina - - Lime - - - Oxide of iron Potass - - - Water - - - From Passan. From St Yrieux. 45-06 32-00 0-74 0-90 18-0 96-7 46-8 87-3 2-5 130 99-6 i5^?^% * "^^^^ of amber, of Arabic origin, in use upon the Continent KELP ; ( Varec, Fr. ; Wareck, Germ.), is the crude alkaline matter produced bv in- cmerating various species of fuci or sea-weed. They are cut with sickles from the rocks m the summer season, dried and then burned, with much stirring of the pastv ash. I have analyzed many specimens of kelp, and found the quantity of soluble mat- ter in 100 parts of the best to be from 53 to 62, while the insoluble was from 47 to 38. The soluble consisted of — Sulphate of soda - - - . . Soda in carbonate and sulphuret Muriate of soda and potash - . . The Insoluble matter consisted of- Carbonate of lime - - - . Silica -----. Alumina tinged with iron oxide - Sulphate of lime - - - . . Sulphur and loss - - - . . m. c 4. e^x, . 100-0 lOO'O T 1 ®^ ci ^^^'^^s® fPecimens was from Heiskcr, the second from Rona, both in the Isle ^^Skj^, upon the property of Lord Macdonald. From these and many other / 8-0 19-0 8-6 5-5 36-6 37-5 63-0 62-0 24-0 10-0 8-0 0-0 9-0 10-0 0-0 9-5 6-0 8-6 ^ KERMES. analyses which I have made it appears that kelp is a substance of verv variahlp onm position and hence it was very apt to produce anomalous results, whTn empW^^^^^^^ the chief alkalme flux of crown glass, which it was for a very long peTod The f^ l^^^cvfo»us and fucus nodoms are reckoned to afford the best kelp, by incinera- ^r 'fi .\ *^u '^^""T ^''^^ ^ ^'^*^'* P^^^'^^^ "^^'^ *h«y ^re of two or three yeare grpwtli, than when cut younger. The varec, made on the shores of NoLandv^cor tarn almost no carbonate of soda, but much sulphate of soda and potas^ome hvD^ sulphate of potash, choride of sodium, iodide of potassium, and chloride of pSLiuL the average composition of the soluble salts being, according to KGay^Lu^c^e of chloride of sodium 25 of chloride of potassium,^ and a little sulphatJ of notVh The very low pri^ at which soda ash, the dry crude carbonate froni the decomposil tion of sea salt is now sold has nearly superseded the use of kelp, and reSd ?te 7ZtCr ^ ^^^ ^^Profitable-a great misfortune to the Ilig&ands and IsL„d1 Kfc:RMKS. There are two substances so caUed, of totaUy different natures. Kermes mineral IS merely a factitious sulphurel of antimony in a state of impalpable comminution, prepared m the moist way. Its minute examination belongs to pharmaceutical chemistry! It may be obtained perfectly pure, by diluting the proto-chloride of antimony with solution of tartaric acid, and precipitating the metal with sulphureted hydrogen ; or by exposing the finely levi-ated native sulphuret to a boiling solution of carbonate of potash for somS time, and filtering the liquor while boiling hot. The kermes faUs down in a brown-red powder, as the hquor cools. Kermes-grains, alkermes, are the dried bodies of the female insects of the species coccus tlicu, which hves upon the leaves of the qiiercus ilex (pricklv oak). The word kermea is Arabic, signifies httle worm. In the middle ages, this dye stuff was therefore caUed vermiculus m Latin, and vermilion m French. It is curious to consider how the name vermilion has been since transferred to red sulphuret of mercury. Kermes has been known in the East since the days of Moses ; it has been employed from time immemorial in India to dye silk; and was used also by the ancient Greek and Roman dyers. Plmy speaks of it under the name of coccigranum, and says that there grew upon the oak in Africa, Sicily, &e. a smaU excrescence like a bud, called ^sculmm; that the Spaniards paid with these grains, half of their tribute to the Romans ; that those produced in Sicily were the worst ; that they served to dye purple • and that those from the neighborhood of Emerita in Lusitania (Portugal) were the best. In Germany, during the ninth, twelfth, thirteenth, and fourteenth centuries, the rural serfs were bound to deliver annually to the convents, a certain quantity of kermes the coccus polomcus, among the other products of husbandry. It was coUected from the trees upon Saint John's day, between eleven o'clock and noon, with religious ceremonies, and was therefore called Johannisblut (Saint John's blood), as also German cochineal. At the above period, a great deal of the German kermes was consumed in Venice, for dyeing the scariet to which that city gives its name. After the discovery of America, cochineal hav- mg been introduced, began to supersede kermes for all brilliant red dyes. The principal varieties of kermes are the coccus quercusy the coccus poUmicus. the coccus jragarice, and the coccus uva ursi. The coccus quercus insect lives in the south of Europe upon the kermes oak. The female has no wings, is of the size of a smaU pea, of a brownish-red color, and is covered with a whitish dust. From the middle of May to the middle of June the eggs are collected, and exposed to the vapor of vinegar, to prevent their incubation. A portion of eggs IS left upon the tree for the maintenance of the brood. In the department of the Bouches- du-Rhone, one half of the kermes crop is dried. It amounts annually to about 60 quintals or cwts., and is warehoused at Avignon. The kermes of Poland, or coccus polonicus, is found upon the roots of the scleranthus perennis and the scleranthus annuus, in sandy soils of that country and the Ukraine. This species has the same properties as the preceding ; one pound of it, according to Wolfe, being capable of dyeing 10 pounds of wool ; but Hermstaedt could not obtain a fine color, although he employed 5 times as much of it as of cochineal. The Turks, Arme. mans, and Cossacks, dye with kermes their morocco leather, cloth, silk, as well as tne manes and tails of their horses. The kermes called coccus fragaria, is found principally in Siberia, upon the root of the common strawberry. The coccus uva ursi is twice the size of the PoUsh kermes, and dyes with alum a fim- red. It occurs m Russia. Kermes is found not only upon the lycopodium complanatum in the Ukraine, but upon a great many other plants. Good kermes is plump, of a deep red color, of an agreeable smell, and a roush and pungent taste. Its coloring matter is soluble in water and alcohol ; it becomes yellowish or brownish with acids, and violet or crimson with alkalis. Sulphate of iron blackens iU I KOUMISS. • "With alum it dyes a blood-red ; with copperas an agat« ip^? » "with copperas and tartar, a lively gray ; with sulphate of copper and tartar, an olrve green ; with tartar and salt of tin, a lively cinnamon yellow ; with more alum and tartar, a lilach ; with sulphate of zinc and tartar, a violet. Scarlet and crimson dyed with kermes, were called grain colors ; and they are reckoned to be more durable than those of cochineal, as is proved by the bril- liancy of the old Brussels tapestry. Hellot says that previous to dyeing in the kermes bath, he threw a handful of wool into it, in order to extract a blackish matter, which would have tarnished the color. The red caps for the Levant are dyed at Orleans with equal parts of kermes and madder j and oc- casionally with the addition of some Brazil wood. Cochineal and lac-dye have now nearly superseded the use of kermes as a tinctorial si^bstance, in England. KILLAS is the name by which clay-slate is known among the Comish miners. KILN (Four, Fr. ; Of en. Germ.) is the name given to various forms of furnaces and stoves, by which an attempered heat may be applied to bodies ; thus there are brick- kilns, hpp-kilns, lime-kilns, malt-kins, and pottery-kilns. Hop and malt-kilns, being designed merely to expel the moisture of the vegetable matter, may be constructed in the same way. See Brick, Limestone, Malt, and Pottery, for a description of their respective kilns. KINIC ACID ; a peculiar acid extracted by Vauquelin from cinchona. KINO is an extractive matter obtained from the nauclea gambir, a shrub which grows at Bancoul and Sumatra, but principally in Prince of Wales' island. It is of a reddish-brown color, has a bitter styptic taste, and consists chiefly of tannin. It is used only as an astringent in medicine. Kino is often called a gum, but most im- properly. KIRSCHWASSER is an alcoholic liquor obtained by fermenting and distilling bruised cherries, called kirsrhen in German. The cherry usually employed in Switzerland and Germany is a kind of morello, which on maturation becomes black, and has a kernel very large in proportion to its pulp. When ripe, the fruit being made to fall by switching the trees, is gathered by children, thrown promiscuously, unripe, ripe, and rotten into tubs, and crushed either by hand, or with a wooden beater. The mashed materials are set to ferment, and whenever this process is complete, ^he whole is transferred to an old still covered with verdigris, and the spirit is run off in the rudest manner possible, by placing the pot over the common fire-place. The fermented mash is usually mouldy before it is put into the alembic, the capital of which is luted on with a mixture of mud and dang. The liquor has accordingly, for the most part, a rank smell, and is most dangerous to health, not only from its own crude essential oil, but from the prussic acid, derived from the distillation of the cherry- stones. There is a superior kind of kirschwasser made in the Black Forest, prepared with fewer kernels, from choice fruit, properly pressed, fermented, and distilled. KNOPPERN are excrescences produced by the puncture of an insect upon the flower-cups of several species of oak. They are compressed or flat, irregularly pointed, generally prickly and hard ; brown when ripe. They abound in Styria, Croatia, Sclavonia, and Natolia ; those from the latter country being the best. They contain a great deal of tannin, are much employed in Austria for tanning, and in Germany for dyeing fawn, gray, and black. Wool, with a mordant of sulphate of zinc, takes a grayish nankeen color. See Galls. KOUMISS is the name of a liquor which the Calmucs make by fermenting mare's milk, and from which they distil a favorite intoxicating spirit, called rack or racky. Cow's milk is said to produce only one third as much spirit, from its containing probably less saccharine matter. The milk is kept in bottles made of hides, till it becomes sour, is shaken till it casts up its cream, and is then set aside in earthen vessels in a warm place to ferment, no yeast being required, though sometimes a little old koumiss is added. 21 pounds of milk put into the still afford 14 ounces of low wines, from which 6 ounces of pretty strong alcohol, of an unpleasant flavor, are obtained by rectification. / LABOR-SAVING MACHINES. LABDANUM or Ladanum, is an unctuous resin, of an agreeable odor, found be- smearing the leaves and twigs of the cystun creticus, a plant which grows in the island of Candia, and in Syria. It is naturally a dark-brown soft substance, but it hardens on keeping. Its specific gravity is 1 -186. It has a bitter taste. Its chief use is in sur- gery for making plasters. LABOR-SAVING MACHINES ix the Great Exhibition. — Printing and numbering Cards. — It will be remembered, that in the early da3S of railway travelling, the ticket system then in vogue at the various stations was a positive nuisance; as every ticket before it was delivered to a passenger had to be stamped, and torn out of a book, thus causing the loss of considerable time to travellers when many passengers were congregated. But this was the least ovil; for the railway directors had little or no check upon their servants, and therefrom resulted many ingenious and successful frauds. The first to remedy this was Mr. Edmondson, who constructed an ingenious apparatus for printing the tickets with consecutive numbei-s, and also dating the sanae. This gave great facilities for cheeking the accounts of the station clerks ; but owing to the imperfect manner of inking, consequent on the construction of the ap- paratus, the friction to which the tickets were exposed, before they were delivered up, in a great measure obliterated the printing, and occasionally rendered them quite illegible. By Messrs. Church and Goddard's machine for printing, numbering, cut- ting, counting, and packing railway ticket.'*, this difficulty also is removed, and great speed is attained in manufacturing the tickets, as the several operations which we have enumerated are simultaneously performed. Pasteboard cut into strips by means of rollers, as above explained, is fed mto the machine, by being laid in a trough, and brought under the prongs of a fork (working with an intermitting movement), which pushes the strips successively forward between the first pair of a series of guide or carrying rollers. There are four pairs of rollers, placed so as to conduct the strip through the machine in a horizontal line ; and an intermittent movement is given them for the purpose of carrying the strips forward a short distance at intervals. The standards of the machine carry, at the top, a block, termed the " platten," as it acts the part of the press head in the common printing machine, — ^portions of it projecting downwards between the upper rollers of the fii st and second, and second and third, pail's of carrying rollers, nearly to the horizontal plane, in which the pasteboard lies, so as to sustain it at those pomts while it receives the pressure of the printing types and numbering discs, hereafter referred to. The types to designate the nature of the ticket, as "Birmingham, First class," are secured in a "chase," upon a metal plate or table, which also carries the numbering discs for imprinting the figures upon the cards ; and the table by a cam action is alternately raised, to bring the types and num- bering discs in contact with the pasteboard, and then lowered into a suitable position to admit of an inking roller moving over the types and numbering discs, and applying •ink thereto. The table likewise carries at one end a knife, which acts in conjunction with a knife-edge projecting downwards from the fixed head of the machine, and thereby gives the cross cut to the strips between the third and fourth pairs of carry- ing rollers, — thus severing each into a given number of tickets. The strip of paste- board which is fed into the machine stops on arriving at the second pair of carrying rollers ; and, on the ascent of the printing-table, the tj'pes print on that portion which is between the first and second pairs of rollers. The strip then passes on to the third pair of rollers, where it stops ; and, on the table again ascending, the numbering discs imprint the proper number upon the pasteboard between the second and third pairs ; the type, in the meanwhile, printing what is to be the next following ticket. On the next ascent of the table, the strip has advanced to the fourth pair of rollers ; and the knives being now brought into contact, the printed and numbered portion of the strip is severed. The now completed ticket is lastly delivered by the fourth pair of rollers into a hollow guide piece, and conducted to a box below, provided with a piston, which, to facilitate the packing of the tickets in the box, can be adjusted to any height to re- ceive the tickets as they fall. To avoid the necessity of having to count the tickets after they are taken from the receiving box, a counting apparatus, connected with the work- ing parts of the machine, is made to strike a bell on the completion of every hundred or more tickets, so as to warn the attendant to remove them from the box. The inking apparatus is assimilated in character to self-acting inkers in ordinary printing presses ; and the numbering discs are worked in a manner very similar to those for paging books. A simple arrangement of apparatus for printing and numbering cards was exhibited by Messrs. Harrild & Sons. The types are fixed in a metal frame, which also carries the numbering discs. This frame is mounted on a rocking shaft, and is furnished with a W LABOR-SAVING MACHINES. 6 handle, whereby it is rocked to bring down the types and discs upon the card, to pro- duce the impression. When the frame is raised again, the units disc is moved forward one figure, and the types are inked by a small roller, which takes its supply of ink from an inking table, that forms the top of the frame. This is a useful description of ma- chine ; but the specimen in the Exhibition does not appear to have been properly ad- justed, as the figures of the numbering discs have a tendency to cut through the card. M. Baranowski, of Paris, exhibits a machine for printing and numbering tickets, and also indicating the number printed. The types and numbering discs are carried by a horizontal rotating shaft, upon which, near each end thereof is a metal disc; and upon the periphery of these discs, a metal frame is affixed, which carries the types and numbering discs, and corresponds in curvature with the edge of the discs. The types for printmg the inscription upon the ticket are arranged at right angles to the length of the shaft, which position admits of some lines of the inscription being printed in one color, and the remainder in another color. In the type frame a slot or opening is formed lengthwise of the shaft ; and behind this opening are three numbering discs, and three discs for indicating the quantity of tickets numbered, — all standing in the same row. The numbering discs are made with raised figures, which project through the slot^ in order to print the number upon the ticket; and on the peripheries of the registering discs (which move simultaneously with their corresponding numbering discs), the figures are engraved. The tickets to be printed and numbered are placed in a rectangular box or receiver, having at the bottom a flat sliding piece, which has a reciprocating motion for the purpose of pushing the lowest ticket out of the box, through an opening in the front side thereof beneath an elastic pressing-roller of In- dia-rubber ; the type frame (with the types and figures properly inked), is at the same time brought, by the rotation of its shaft, into contact with the ticket beneath the pressing-roller, and as it continues its motion, it causes the ticket to move forward beneath the pressing-roller, and to be properly printed and numbered. The ticket then falls from the machine ; and the type frame, carried on by the revolution of the shaft, brings that number on the registering discs, which corresponds with the num- ber printed on the ticket, under a small opening in the case, covered with glass; whereby the number of tickets printed will be indicated. Backing Books. — Not altogether foreign to the subject of printing is the contribution of Mr. C. Star, of New- York, United States, who exhibits two machines for booksellers' use, — the one being employed for backing, and the other for finishing the backs of books. The two machines are similar to each other, as regards the subordinate parts, but diflFer in some other respects. In the backing machine, the stitched sheets, forming the book, are fixed in a pair of iron clumps, somewhat larger then the book itself. The clumps are mounted on horizontal pivots, and furnished with a weighted lever, which gives them a tendency to move out of the vertical line, and thereby bring the back of the book, which stands up above the edges of the clumps, under the action of a smooth metal roller. This roller turns in bearings which are capable of sliding vertically in the framing of the ma- chine : and the bearings are pressed upon by two weighted levers, when the machine is in use, so as to cause the roller to bear down forcibly upon the book. While the roller is in this position, the weighted lever of the clumps causes the book to oscillate, and thus the rounding of the back is etfected. The movemeni; of the clumps under the roller is regulated by the workman through a foot treadle, connected with the lever in the machine for finishing the backs; the roller is engraved with any suitable de- sign ; and the cross piece which supports its bearings, is made hollow, and is heated bv steam, for the purpose of communicating heat to the roller. Motion in this case is given to the clump by a winch-handle, instead of the weighted lever, and the pattern on the roller is thereby embossed upon the back of the book. — Newton's Journal. Washing and Mangling. — ^The British portion of the Great Exhibition contained nu- merous examples of the application of machinery to economize labor in the processes of washing, wringing, and mangling. The washing machines may be divided into three classes, viz., first, those which have a rotary action ; secondly, those wherein vibrating beaters are employed ; and thirdly, those in which vertical beaters are ultimately raised and permitted to fall upon the clothes. In the first class, Mr. V. Price, of Wardour Street, Soho, has a simple machine, con- sisting of a cylinder or drum, to contain the clothes, revolving horizontally in a close wooden vessel, or outer case, which holds the soap-suds. The drum is made with solid ends; but (in order that the soap-suds may have free access to the clothes), the periphery or body thereof is composed of wooden bars or spokes, extending from one end to the other, with a space somewhat greater than the width of a bar between the adjacent bars, so as to resemble what is known to engineers as a "lantern drum." Tiie clothes are introduced by opening a door in the side of the drum ; and on rotary mo- tion being given to the drum by a handle, the soap-suds will be caused to act upon and thoroughly cleanse the clothes. y 6 LABOR-SAVING MACHINES. Mr. J. Adaraa, of Selby, exhibited a machiae, in wliich the articles to be washed were placed in a perforated wooden barrel or octagonal vessel, rotating hoiizontilly in an outer case. Above the case two wooden rollers are mounted, one over the other • and the clothes, when sufficiently washed, are passed between such rollers, so sis to squeeze out the soap-suds, instread of wringing the clothes by hand. These rollers may be subsequently used for mangling the clothes. Another rotary machine, exhibited by Mr. Pearson, of Leeds, consists of a tub or wooden vessel, in which the clothes are thrown ; and the requisite agitation for wash- ing or discharging the dirt is effected by means of an upright beater, which rotates in the tub in the same manner as the " dasher " of an upright rotary churn. This appara- tus is also provided with a pair of rollers for wringing and mangling the clothes. The next machines of the rotary class which we shall notice, are those of Messrs. Manloye, Alliott, movements of the discs for effecting thi rLni ' ^^ ^^'^ ^^^^^n^ the requisite duced ; the first wheel driving its o^ndis/l^^^^^^^ «^ '^^ """^bers a?e pro! the next disc, and the other whLl each rec.ivJn"."'"*^'"^ "^"^^^^ *<^ intervafsto onfo? q?or:trv:::rfl[:rE^ ^t'ef?^:? IL'^S^^^ ^5 IrV^^^^^ spHng-cat^h ^'^hf nu?b:r!lSay fe P^^^d%^^^^^^^^^^^^^ ^^^ n^^fmrreU^^-^^ ^^^^^^"^ ^^ or all odd nt^Tby Vri g r^^^^ I^ond c:t:h l^to ^7^'^^T' T ^ ^^^ P^^ '^^ -en to advance one step during the arpmll ^""^T' ^*^^«^ ^a^ses the unit disc advance during the^descent^of tL sam^^^^ "^^^ ^^"°^^' ^^ *^<^ition ^ the LABRADORITE. onalinp nr r oK^ r t^'^'^ * Journal, xxxviii. 43a changing colors^luC/ed^an^^^^^^^ t'eT' ^ ^^r^iful niine^, with brilliant affords no water by calcin'ation fSlt at thl^hf^J'- ''* ^'^^ *^ ^'"^^^ ^^^^tches gS muriatic acid; solution affords a S^^^^^ frothy bead; soluble in' ages of 93|° and 86^ : one of whirh^« K?fn^ ^l ^,^'*^ ""^^^^te of ammonia. Cleav- 55;75; aluLina,264;'C7ii7sSt 4^;^"i^ Its constituents are sS, LABYRINTH, in ietaUurgy,' m^ns a serie. nf ''''"'. ^1? ' ^^'^^> O'^' a stamping-miU; through whkh^ands a s^relm^n? f ^^^^"^"ted in the sequel of mg, .rrying off, and depositing, ar^er^nf SI^LT^ ^^ ^^ t "S^S^ the^lPnk^^™ Stick-Iacis produced by of several plants; as the Jicus rellgiosa thefill^Zi^''^''' f""'* "P^" ^« ^^^"^hes abar. The twig becomes thereby inTrSstef^li^ ^^^ ^''*™' ^^^' ^^°?^» and Mal- crystaUine-looking fracture, """^^^y '''*'"*^^^^ ^thr a reddish mammelated resin, having a The female lac insect is of the shf nf « i« circles, a bifurcated tail, antenn^^d 6 Iws haff\h^^^ 'TVf'.^^'^ ^^ abdominal twice the above size, and has 4 winX. thl^7^' *i^^, ^^"^^^ «^ the body. The male is ber or December theVoun^roc^Sef^^s elT f^'^!?^ to 5000 females. In Novem! body of the mother ; they crawl a W a l/ttl?l^ ""^^^^ ^^^^' ^>'i"? ^^n^^th the dead the shrubs. About this perirthe baches oft p?' ^""^ ^^'^''^ themselves to the bark of min that they seem covered with a rSdus^ .7^" '" '^'\^ ^^^^^^ ^^^^ '^^ verw by being exhausted of their juices Manv nf ?», ''.''^'^' ^^^^ ^^ «?* to dry up, juices. Many of these insects, however, become the LAC, LAC DYE. 11 )' prey of others, or are carried off by the feet of birds, to which they attach themselves, and are transplanted to other trees. They soon produce small nipple-like incrusta* tions upon the twigs, their bodies being apparently glued, by means of a transparent liquor, which goes on increasing to the end of March, so as to form a cellular texture. At this time, the animal resembles a small oval bag, without life, of the size of cochineal. At the commencement, a beautiful red liquor only is perceived, afterwards eggs make their appearance ; and in October or November, when the red liquor gets exhausted, 20 or 30 young ones bore a hole through the back of their mother, and come forth. The empty cells remain upon the branches. These are composed of the milky juice of the pilfint, which serves as nourishment to the insects, and which is afterwards transformed or elaborated into the red coloring matter that is found mixed with the resin, but in greater quantity in the bodies of the insects, in their eggs, and still more copiously in the red liquor secreted for feeding the young. After the brood escapes, the cells contain much less coloring matter. On this account, the branches should be broken off before this happens, and dried in the sun. In the East Indies this operation is performed twice n the year ; the first time in March, the second in October. The twigs incrusted with the radiated cellular substance constitute the stick4ac of commerce. It is of a red color, more or less deep, nearly transparent, and hard, with a brilliant conchoidal fracture. The stick-lac of Siam is the best ; a piece of it presented to me by Mr. Rennie, of Fen- chuich-street, having an incrustation fully one quarter of an inch thick all round, the twig. The stick-lac of Assam ranks next ; and last, that of Bengal, in which the resinous coat is scanty, thin, and irregular. According to the analysis of Dr. John, stick-lac consists, in 120 parts, of — An odorous common resin - - • A resin insoluble in ether - - - Coloring matter analogous to that of cochineal Bitter balsamic matter - _ - Dun yellow extract - - - - Acid of the stick-lac (laccic acid) - Fatty matter, like wax - - - Skin of the insects and coloring matter Salts ..... Earths - - . - . Loss - • • . • ♦ . 80-00 20-00 4-50 3-00 0-50 0-75 3-00 2-.50 l-2i> 0-75 4-75 120-00 %. According to Franke, the constituents of stick-lac are, resin, 65-7 ; substance of the lac, 28-3 ; coloring matter, 0-6. Seed-lac. — When the resinous concretion is taken off the twigs, coarsely pounded, and triturated with water in a mortar, the greater part of the coloring matter is dissolved, and the granular portion which remains, being dried in the sun, constitutes seed-lac. It con- tains of course less coloring matter than the stick-lac, snd is much less soluble. John found in 100 parts of it, resin, 66-7; wax, 1-7; matter of the lac, 16-7; bitter balsamic matter, 2-5; coloring matter, 3-9; dun yellow extract, 0-4 ; envelopes of insects, 2-1 j laccic acid, 0-0 ; salts of potash and lime, 1-0 ; earths, 6-6 ; loss, 4-2. In India the seed-lac is put into oblong bags of cotton cloth, which are held over a charcoal fire by a man at each end, and, as soon as it begins to melt, the bag is twisted so as to strain the liquefied resin through its substance, and to make it drop upon smooth stems of the banyan tree {musa paradisa). In this way, the resin spreads into thin plates, and constitutes the substance known in commerce by the name of shellac. The Pegu stick-lac, being very dark-colored, furnishes a shellac of a corresponding deep hue, and therefore of inferior value. The palest and finest shellac is brought from the northern Circar. It contains very little coloring matter. A slick-lac of an interme- diate kind comes from the Mysore country, which yields a brilliant lac-dye and a good shellac. Lac-dye is the watery infusion of the ground stick-lac, evaporated to dryness, and formed into cakes about two inches square and half an inch thick. Dr. John found it to consist of coloring matter, 50 ; resin, 25 ; and solid matter, composed of alumina, plaster, chalk, and sand, 22. Dr. Macleod, of Madras, informs me that he prepared a very superior lac-dye from stick-lack, by digesting it in the cold in a slightly alkaline decoction of the dried leaves of the MemecyUm tinctorium (perhaps the M. capitellatum, from which the natives of Malabar and Ceylon obtain a safl'ron-yellow dye). This solution being used along with a mordant, consisting of a saturated solution of tin in muriatic acid, was found to dye woollen cloth of a very brilliant scarlet hue. / 12 LAC, LAC DYE. LACE BOBBINET. 13 The cakes of lac-dye imported from India, stamped with peculiar marks to designate their different manufacturers, are now employed exclusively in England for dyeing scarlet cloth, and are found to yield an equally brilliant color, and one less easily affected by perspiration than that produced by cochineal. "When the lac-dye was first introduced, sulphuric acid was the solvent applied to the pulverized cakes, but as mu- riatic acid has been found to answer so much better, it has entirely supplanted it. A good solvent (No. 1) for this dye-stuff may be prepared by dissolving three pounds of tin in 60 pounds of muriatic acid, of specific giavity 1*19. The proper mordant for the cloth is made by mixing 27 pounds of muriatic acid of sp. grav. 1*17, with 1^ pounds of nitric acid of 1*19; putting this mixture into a salt-glazed stone-bottle, and adding to it, in small bits at a time, grain tin, till 4 pounds be dissolved. This solution (No. 2) may be used within twelve hours after it is made, provided it has become cold and clear. For dyeing, three quarters of a pint of the solvent No. 1 is to be poured upon each pound of the pulverized lac-dye, and allowed to digest upon it for six hours. The cloth, before being subjected to the dye bath, must be scoured in the mill with fullers' earth. To dye 100 pounds of pelisse cloth, a tin boiler of 300 gallons capacity should be filled nearly brimful with water, and a fire kindled under it. Whenever the temperature rises to 150° Fahr., a handful of bran and half a pint of the solution of tin (No. 2) are to be introduced. The froth, which rises as it approaches ebullition, must be skijinmed off; and when the liquor boils, 10| pounds of lack-dye, previously mixed with 7 pints of the solvent No. 1, and 3| pounds of solution of tin No. 2, must be poured in. An instant afterwards, 10| pounds of tartar, and 4 pounds of ground sumach, both lied up in a linen bag, are to be suspended in the boiling bath for five minutes. The fire being now withdrawn, 20 gallons of cold water, with 10| pints of solution of tin, being poured into the bath, the cloth is to be immersed in it, moved about rapidly during ten minutes j the fire is to be then rekindled, and the cloth winced more slowly through the bath, which must be made to boil as quickly as possible, and maintained at that pitch for an hour. The cloth is to be next washed in the river ; and lastly, with water only, in the fulling mill. The above proportions of the ingredients produce a brilliant scarlet tint, with a slightly purple cast. If a more orange hue be wanted, white Florence argal may be used, instead of tartar, and some more simiach. Lac-dye may be substituted for cochineal in the orange-scarlets; but for the more delicate pink shades, it does not answer so well, as the lustre is apt to be impaired by the large quantity of acid necessary 10 dissolve the coloring matter of the lac. Shellac, by Mr. Hatchett's analysis, consists of resin, 90*5; coloring matier, 0*5; wax, 4*0 ; gluten, 2*8 ; loss, 1'8 ; in 100 parts. The resin may be obtained pure by treating shellac with cold alcohol, and filtering the solution in order to separate a yellow gray pulverulent matter. When the alcohol is again distilled off, a brown, translucent, hard, and brittle resin, of specific gravity 1*139, remains. It melts into a viscid mass with heat, and difluses an aromatic odor. Anhydrous alcohol dissolves it in all proportions. According to John, it consists of two resins, one of which dissolves readily in alcohol, ether, the volatile and fat oils ; while the other is little soluble in cold alcohol, and is msoluble in ether and the volatile oils. Unverdorben, however, has detected no less than four dift'erent resins, and some other substances, in shellac. Shellac dissolves with ease in dilute muriatic and acetic acids ; but not in concentrated sulphuric acid. The resin of shellac has a great tendency to combine with salifiable bases ; as with caustic potash, which it depiives of its alkaline taste. This solution, which is of a dark red color, dries into a brilliant, transparent, reddish brown mass ; which may be re-dissolved in both water and alcohol. By passing chlorine in excess through the dark-colored alkaline solution, the lac-resin is precipitated in a colorless state. When this precipitate is washed and dried, it forms, with alcohol, an excellent pale-yellow varnish, especially with the addition of a little turpentine and mastic. With the aid of heat, shellac dissolves readily in a solution of borax. The substances which Unverdorben found in shellac are the following : 1. A resin, soluble in alcohol and ether ; 2. A resin, soluble in alcohol, insoluble in ether ; 3. A resinous body, little soluble in cold alcohol ; 4. A crj'stallizable resin ; 5. A resin, soluble in alcohol and ether, but insoluble in petroleum, and uncnrs- tallizable. 6. The unsaponified fat of the coccus insect, as well as oleic and margaric acids. 7. Wax. 8. The laccine of Dr. John. 9. An extractive coloring matter. • 4 Statistical Table of Lac-Dye and Lac-Lake, per favor of James Wilkinson, Esq*, of Leadenhall street. Import. Export. Horn* Consumption. Prices. Stocks. lbs. lbs. Jbs, 1802 253 none 1803 1,735 none acctunt burned 1804 531 _ 1805 1,987 1806 none 1807 25,350 1808 5,731 1809 40,632 1810 235,154 1811 378,325 1812 198,250 1813 289,654 1814 278,899 5,071 133,935 1815 598,592 8,441 137,915 I8I6 269,373 27,412 162,894 1817 384,909 23,091 234,763 1818 242,572 32,079 323,169 1819 179,511 21,707 20 ,063 • 1820 441,486 49,519 9^2,514 1821 641,755 91,925 322,837 1822 872,967 29,578 349,351 1823 534,220 13,050 414,714 1824 604,269 53,843 483,339 1825 541,443 61,908 385,734 1826 760,729 68.603 395,609 1827 756,315 76,875 448,270 1 9 4 11,538 1828 512,874 54,999 397,867 1 3 3 9 11,085 1829 475,632 39,344 433,851 1 3 3 6 11,976 1830 534,341 78,099 5-1 8^865 9 3 3 11,834 1831 913,562 175,717 597,568 4 2 6 12,559 1832 378,843 69,842 594,155 4 2 3 11,420 1833 326,894 66,447 426,460 9 2 4 11,457 1834 708,959 89,229 398,832 11 2 4 11,928 1835 528,564 203,840 573,288 11 3 10,454 1836 612,436 200,975 642,615 1 4 9,492 1837 1,011,674 133,959 427,890 1 3 9 8,780 The stock includf ?s 2,200 chests of Lac-lake • Landings, Deliveries, and Stocks of Lac Dyes. Year. In December 1851 1850 In 12 months 1851 1860 1849 1848 I.an(l(>4 chests 564 7152 5SG0 3264 15T7 Delivered. ?92 chests ^^ 308 __ 4741 7777 4063 5356 4126 8559 8020 4421 Stock Ist January. — chests I >\ Layton, Hulbcrt, dt Co.'s Circular, 1th Jan,, 1852. The market prices on 8tli Jan. 1852 were from 3c?. to 2% 4d. per lb. LACCIC ACID crystallizes, has a wine-yellow color, a sour taste, is soluble in water, alcohol, and ether. It was extracted from stick-lac by Dr. John. LACCINE is the portion of shell-lac which is insoluble in boiling alcohol. It is brown, brittle, translucid, consisting of agglomerated pellicles, more like a resin than any thing else. It is insoluble in ether and oils. It has not been applied to any use. LACE BOBBINET. Ilithorto the threads of silk, flax, or cotton, used as the chain or warp in the manufacture of lace or net, have been warped, or ranged side by side, and in this state wound upon a c^iinder, which being mounted upon an axle or shaft, delivers the warp threads as each^uesh of the net is formed. By the patented arrange- ment of Mr. W. E. Newton, whatever may be the difference in the consumption of the several threads to produce the fabric, in cornjiarison with other portions of the warp, the cylinder will always deliver the same quantity in length of each thread. This u LACE MANUFACTURE. LACE MANUFACTURE. 15 ^ u^\u^?^ *^ ^^^^* inconvenience. According to the present invention, for every thread a bobbin is provided for regulating its tension; and thus each separate thread or number of threads may, without inconvenience, furnish a greater or less length of warp as may be required. See the details, with figures, in Newton's London JourncU, 3E5XV. 391. * LACE MANUFACTURE. The piUow-made, or bone-lace, which formerly gave occupation lo multitudes of women in their own houses, has, in the progress of me- chanical invention, been nearly superseded by the bobbin-net lace, manufactured at first by hand-machines, as stockings are knit upon frames, but recently by the power of water or steam. This elegant texture possesses all the strength and regularity of the old Buckingham lace, and is far superior in these respects to the point-net and warp lace which had preceded, and in some measure paved the way for it. Bobbin-net may be said to surpass every other branch of human industry in the complex ingenuity of its machmer}'; one of Fisher's spotting frames* being as much beyond the most curious chronometer, m multipUcity of mechanical device, as that is beyond a common roastin*'- jack. ^ The threads in bobbin-net lace form, by their intertwisting and deccussation, re«nilar hexagonal holes or meshes, of which the two opposite sides, the upper and under are Oirected along the breadth of the piece, or at right angles to the selvage or border. Fig. 833 shows how, by the crossing and twisting of the threads, the regular six- sided mesh is produced, and that the tex- ture results from the union of three sepa- rate sets of threads, of which one set pro- ceeds downwards in serpentine lines, a second set proceeds from the left to the ris:ht, and a third from the right to the left, both in slanting directions. These oblique threads twist themselves round the vertical ones, and ialso cross each other be- twixt them, in a peculiar manner, which may be readily understood by examining the representation. In comparing bobbin- net with a common web, the perpendicular threads in the figure, which are parallel to the border, may be regarded as the warp, and the two sets of slanting threads, as the weft. These warp threads are extended up and down, in the original mounting of the piece between a top and bottom horizontal roller or beam, of which one is called the warp beam, and the other the lace beam, because the warp and finished lace are wound upon them respectively. These straight warp threads receive their contortion from the tension of the weft threads twisted obliquely round them alternately to the right and the left hand. Were the warp threads so tightly drawn that they became inflexible, like fiddle-strings, then the lace would assume the appearance shown in fig 834; and although this condition does not really exist, it may serve to illustrate the structure of the web. The warp threads stand in the positions a a, a' a', and a" a" j the one half of the weft proceeds in the direction b h, b' b', and b" b" ; and the second crosses the fiist bv running in the direction c c, oi c' c', towards the opposfile side of the fab- ric. \i we pursuf. the path of a wefl thread, we find it goes on till it reaches the outermost or last warp thread, which it twists about ; not once, as with the others, but twice ; and then returning towards the other border, proceeds in a reverse direc- tion. It is by this double twist, and by the return of the weft threads, that the selvage is made. The ordinary material of bobbin-net is two cotton yarns, of from No. 180 to No. 250, twisted into one thread ; but some- times strongly twisted single yarn has been used. The beauty of the fabric depends upon the quality of the material, as well as the regularity and smallness of the meshes. The number of warp threads in a yard in ^■. breadth is from 600 to 900 ; which is equivalent to from 20 to 30 in an inch. The size of the holes cannot be exactly inferred from that circumstance, as it depends partly upon the oblique traction of the threads. The breadth of the pieces of bobbin-net varies from edgings of a quarter of an inch, to webs 12, or even 20 quarters, that is, 5 yards wide. Bobbin-net lace is manufactured by means of very costly and complicatea machines, called frames. The limits of this Dictionary will admit of an explanation of no more than the general principles of the manufacture. The threads for crossing and twisting round the warp, being previously gassed, that is, freed from loose fibres by singeing with gas, are wound round small pulleys, called bobbins, which are, with this view, deeply grooved in their periphery. Figs. 836. 836. exhibit the bobbin alone, and with its carriage, 836 835 \ In the section of the bobbin a, fig. 835. the deep groove is shown in which the thread is wound. The bobbin consists of two thin discs of brass, cut out in a stamp-press, in the middle of each of which there is a hollow space c. These discs are riveted together, leaving an interval between their edge all round, in which the thread is coiled. The round hole in the centre, with the little notch at top, serves for spitting them upon a feathered rod, in order to be filled with thread by the rotation of that rod in a species of reel, called the bobbin-filling machine. Each of these bobbins (about double the size of tho figure), is inserted into the vacant space g, of the carriage, fig. 836. This is a small iron frame (also double the size of the figure), which, at € c, embraces the grooved border of the bobbin, and by the pressure of the spring at /, prevents it from falling out. This spring serves likewise to apply sufficient friction to the bobbin, so as to prevent it from giving off' its thread at g by its rotation, unless a certain small force of traction be employed upon the thread. The curvilinear groove h h, sunk in each face or side of the carriage, has the depth shown in the section at h. This groove corresponds to the interval between the teeth of the comb, or bars of the bolt, in which each carriage is placed, and has its movement. A portion of that bolt or comb is shown at a, fig. 837 in plan, and one bar of a circular bolt machine at 6, in section. If we suppose two such combs or bolts placed with the ends of the teeth opposite each other, but a little apart, to let the warp threads be stretched, in one vertical plane, between their endf or tips, we shall have an idea of the skeleton of a bobbin-net machine. One of these two combs, in the double bolt machine, has an occasional lateral movement called shagging^ equal to the interval of one tooth or bolt, by which, after it has received the bobbins, with their carriages, into its teeth, it can shift that interval to the one Side, and thereby get into a position to return the bobbins, with their carriages, into the next series of in- terstices or gates, in the other bolt. By this means the whole series of carriages receives successive side steps to the right in one bolt, and to the left in the other, so as to per- form a species of countermarch, in the course of which they are made to cross and twist round about the vertical warp threads, and thus to form the meshes of the net. The number of movements re- quired to form a row of meshes in the double tier machine, that is, in a frame with two combs or bars, and 2 rows of bobbins, is six j^ that is. 16 LACE MANUFACTURE. the whole of the carrias^es (with their bobbins) pass from one bar or comb to the other SIX times, durin? which passages llie different divisions of bobbin and warp threads chans^e their relative positions 12 times. This intcrchanse or traversing of the carriages with their bobbins, which is the most difficult thing to explain, but at the same time the most essential principle of the lace- machme, may be tolerably well understood by a careful study of fig. 838 in which lhi« 1*2 3 4 5 6 7 8 9 838 LACTIC ACID. 17 ***•<' ii. 4^1" •••ill i. XE Trrp" ; I , i I iiill C; has gone over to the back line. The bobbins and carriages throughout the whole width of the machine have thus crossed each other's course, and completed the mesh of net. The carriages with their bobbins are driven a certain wav from the one comb to the other, by the pressure of two long bars (one for each) placed above the level of the comb ttntil they come into such a position that their projecting heels or catches i Lfis;. 611, are moved off by two other long flat bars below, called the locker plates, and thereby carried completely over the interval between the two combs. - There are six diflerent systems of bobbin-net machines. 1. Heathcoatcs patent maehiuo. 2. Brown's traverse warp. 3. Moriey's straight bolt 4. Clarke's pusher principle, single tier, 5. Leaver's machine, single tier. 6. Morley's circular bolt. All the others are mere variations in the construction of some of their parts. It is a re- markable fact, highly honorable to the mechanicsil judgment of the late Mr. Morlc\ of Derby, that no machines except those upon his circular bolt principle have beeu found capable of working successfully by mechanical power. ^ The circular bolt machine (comb with curved teeth) was used by Mr. Morley, for mak- ing narrow breadths or edgings of lace immediately after its first invention, audit hsis been regularly used by tlie trade for that purpose ever since, in consequence of the inventor having declined to secure the monopoly of it to himself by patent. At that time the locker bars for driving across the carriages had only one plato or blade. A machine so mounted is now called'* the single locker circular bolt" In the year 1824, Mr. Morley added another plate to each of the locker bars, which was a great improvement on the machines for nmking plain net, but an obstruction to the making of narrow breadths upon them. This machine is now distinguahed from the former by the term " double locker." * A rack of lace, is a certain length of work counted perpendicularly, and contains 240 .oK^o ^r. i,^i^o Well-made lace has the meshes a little elongated in the direction of meshes or holes, the selvatje. * By reading the above brief account of Bobbin-net, in connecOon with the most detailed description of It in my Cotton Manufactuke op Great Bkitaik, a tolerably clear conception of the nature of this iotricate manufucture mav be obtained. r \ The term gauge, in the lace manufacture, means the number of gates, slits, or in- lerstices, in one inch of the bolt-bar or comb ; and corresponds therefore to the number of bobbins in an inch length of the double tier. Thus, when we say " gauge nine points," we mean that there are nine gates with nine bobbins in one inch of the comb or bolt-bar. Each of such bobbins with its carriage is therefore no more than one ninth of an inch thick. The common proportion or gauge up and down the machine is 16 holes in the inch for ten bobbins transversely. Circular bolt double tier machines can turn off by steam power fully 360 racks each day of 18 hours, with a relay o** superin- tendents. The number of new mechanical contrivances to which this branch of manufactuie has given rise, is altogether unparalleled in any other department of the arts. Since Mr. Heathcote's first successful patent, in 1809, a great many other patents have been granted for making lace. In the year 1811, Mr. Morley, then of Nottingham, invented his straight bolt frame, more simple in construction, better combined, and more easy in its movements, than the preceding machines ; but the modest inventor did not secure it, as he might have done, by patent. The pusher machine was invented in the same year, by Samuel Mart and James Clark, also of Nottingham. The following year is remarkable in the History of the lace trade, for the invention of the circular bolt machine, by Mr. Morley — a mechanism possessing all the advantages of his straight bolt machine, without its disadvantages. Nearly at the same time Mr. John Leaver brought forward the lever machine, con- jointly with one Turton, both of New Radford, near Nottingham. About the year 1817 or 1818, Mr. Heathcote applied the rotatory movemement to the circular bolt machine, and mounted a manufactory on that plan, by mechanical power, at Tiverton, after he and his partner, Mr. Boden, had been driven from Loughborough, in 1816, by the atrocious violence of the frame-destroying Luddites. Such has been the progress of improvement and economy in this manufacture, that the cost of labor in making a rack, which was, twenty years ago, 3s. 6d.y or 42 pence, is now not more than one penny. The prices of this beautiful fabric have fallen in an equally remarkable manner. At the former period, a 24 rack piece, five quarters broad, fetched 17/. sterling, in the wholesale market ; the same is now sold for 7s. ! The consequence is, that in lace decoration, the maid servant may be now more sumptuously arrayed than her mistress could afford to be twenty years ago. LACKER, is a varnish, consisting chiefly of a solution of pale shellac in alcohol tinged with saftron, annolto, or other coloring matter. See Varnish. LACTIC ACID. (./Icide Lactiqne, Ft.; Milchsaiire, Germ.) This acid was discovered by Scheele in buttermilk, where it exists most abundantly ; but it is present also in fresh milk in small quantity, and communicates to it the property of reddening litmus. Lactic acid may be detected in all the fluids of the animal body ; either free or saturated with alkaline matter. Scheele obtained this acid by evaporating the sour whey of clotted milk to an eighth part of its bulk, saturating this remainder with slaked lime, in order to throw down the subphosphate of lime held in solution, filtering the liquor, diluting it with thrice its weight of water, and precipitating the lime circumspectly, by the gradual addition of oxalic acid. He next filtered, evaporated to dryness on a water batli, and digested the residuum in strong alcohol, which dissolved the lactic acid, and left the sugar of milk. On eva- porating off the alcohol, the acid was obtained. As thus procured, it requires to be purified by saturation with carbonate of lead (pure white lead), and precipitating the solution of this lactate with sulphate of zinc, not added in excess. Sulphate of lead falls, and t!ie supernatant lactate of zinc being evaporated affords crystals at first brown, but which become colorless on being dissolved and recrystallized twice or thrice. It* the sulphuric acid of the dissolved salt be thrown down by water of baryta, the liquid when filtered and evaporated yields a pure lactic acid, of a syrupy consistence, color- less and void of smell. It has a pungent acid taste, which it loses almost entirely when moderately diluted w^ith water. It does not crystallize. Its salts, with the exception of those of magnesia and zinc, have a gummy appearance, and are very soluble in alcohol, unless they hold an excess of base. Lactic acid consists of 44*92 carbon ; 6*65 hydrogen; 48"53 oxygen. It contains 9*92 per cent, of water. It has not hitherto been applied to any use in the arts, except by the Dutch in their old process of bleach- ing linen with sour milk. See Fermentation. ' New method of preparing. — The following process for procuring lactic acid and the lactates is so simple, as to merit a preference over all others heretofore proposed ; it is as follows: — "Take 3 or 4 (litre = 1*76 pint) of milk, into which you pour a solution of from 200 to 300 grammes (gramme =» 15*438 grs. Troy) of sugar of milk ; the liquor is exposed to the air in an open vessel for some days, at a temperature of from 59° to 68° Fahr. It will then be found to have become very acid, and is to be saturated with bicarbonate of soda. After the lapse of 24 or Vol. II. 2 18 LAKES. LAMPS. !• 86 hours it becomes again acid, and must be saturated anew, repeatine the oroce*- until the whole of the sugar of milk has been converted into lactKdd^ Whe^^^^^^^ consi.lered that the transformation is complete, the milk must be boTled tola^late the caseura ; the hqtud is next to be filtered and evaporated to the consistence of s^ruD taking care that the temperature be moderate. The product of evaporat onTs taSn ud by alcohol at 38° which d.ssolves the lactate of sodk Into this alcoSsoluton an adequate quantity of sulphimc acid is to be poured ; the resulting sulphate of soda fa Is down and the hquor by filtration and evaporation affords lactic Lklarinosrimre To obtam It m a state of great purity, it may be saturated with chalk the^acfUe of hme crystallizes directly in white granules, whence we can separate th^ lac'tic add by the ordinary means. «v.i,iv. uv^iu uy It is evident the lactic acid may be saturated with any other base, and afford exDe- ditiously crystallized lactates. ^ «* u auora expe- ..^^F^?^^^^^^ '! *^'^ '''"^? ""^^^ instrument for estimating the quality of milt called also a Galactmneter. The most convenient form of apparatus would be a senes of glass tubes each about 1 inch in diameter, and 12 inches lonrffraduated through a space of 10 inches, to tenths of an inch, having a stop-cock at^'lfebo"^^^^^^ and suspended upright in a frame. The average milk of the cow Sg no red ^To the height of 10 inches, as soon as the cream has all separated at top the thickness of ite body maybe measured by the scale; and then the skim-milk may be run off below into a hydrometer glass, in order to determine its density, or relative I'ichness in caseous matter, and dilution with water. ^ ^cxauve iiciiness LAKES. Under this title are comprised all those colors which consist of a ve^-etable dye, combined by precipitation with a white earthy basis, which is usually alumina'' The general method of preparation is to add to the colored infusion a solution of common alum or rather a solution of alum saturated with potash, especially when the infusion has been made with the aid of acids. At first only a slight precipitate falls, consisting of alumina and the coloring matter ; but on adding potash, a copious precipitation ensues! of the alumina associated with the dye. When the dyes are not injured, but are rathe^ brightened by alkalis, the above process is reversed ; a decoction of the dye-stuff is made with an aUiahne liquor, and when it is filtered, a solution of alum is poured into it. The third method IS practicable only with substances having a great affinity for subsulphate ^^a^umina ; it consists m agitating recently precipitated alumina with the decoction of yellow /«fec5 are made with a decoction of Persian or French berries, to which some potash or soda is added; into the mixture a solution of alum is to be poured as long as any precipitate faUs. The precipitate must be filtered, washed, and formed into cakes, and dried. A lalce may be made in the same way with quercitron, takin? the precautioi to purify the decoction of the dye-stuff with buttermilk or due. After filtering the lake ivfc^L- ^"?h^\"e^,^^;th a solution of tin. Annotto lake is formed by dissolving the dye-stufi m a weak alkahne ley, and addmg alum water to the solution. Solution of tin gives this lake a lemon yellow cast ; acids a reddish tint. Hcd lakes.— The finest of these is carmine. This beautiful pigment was accidentaUy discovered by a Franciscan monk at Pisa. He «nTl ''■'' f I ""^ cochmeal With salt of tartar, in order to employ it as a medicine! « nrn . . r ' "" ^^^^^^^.^^lou of an acid to it, a fine red precipitate. Homberg published n/rp/ h. Z preparing It, m I6dG. Carmine is the coloring matter of cochineal, pre- fhJ 1h^ precipitation from a dcccction of the drug. Its composition varies according to the mode of making it. The ordinary carmine is prepared with alum, and consists of clZT^ ^'"^ Cochineal), a Httle animal matter, almnina, and sulphuric acid. S^e Ca-minated lake caUed lake of Florence, Paris, or Vienna. For making this pigment. tJl^Zo' .f "^^ly ^"^P^^y^'l ^l^i^\is decanted from the carmine process. Imf tM^ mul^ ^ Whl ^^^'? ' • P"l' ^^! °^^^r ^' ''^'^' ^"^ h^^t^d\i little, but not too to^h^owdowrflr ^'^^^'^^^"^ in the decoction of cochineal, and potash is then added, Wiff^ZJ ' ^^^^^^.""^i'^^^" combination with the coloring matter; but in this way an indiiierent pigment is oblamed. OccasionaUy, solution of tin is added, to brighten the is feWom L'/r'e^otsf t'o' '"" """^''^ " ''^ ''''' "^^ ^^ '^^'^ ^^'^^^'^^^^ '' »^"^ ^'^ " Brazil-xoood Zafr^s.— Brazil wood is to be boiled in a proper quantitv of water for 13 Z^Z 'o/t"t;.t" -V°^"^"? '' ^^^^^^^ ^''^'^ the^i?uor^s t^be fiUered, a^^j'a solution of potash poured in as long as it occasions a precipitate. This is separalea by the filter, washed in pure water, mixed with a little gum neater, and made into cakes. Or the BrazQ wood may be boiled along with a little vinegar, the decoction filtered, alum and salt of tin added, and then potash-ley poured in to precipitate the lake. For 1 pound of Brazil wood, 30 to 40 pounds of water, and from 1^ to 2 pounds of alum, may be taken, in producing a deep red lake ; or the same proportions with half a pound of solution of tin. If the potash be added in excess, the tint will become violet. Cream of tartar occasions a brownish cost. . . Madder lake.— A fine lake may be obtained from madder, by washing it in cold water as long as it gives out color; then sprinkling some solution of tin over it, and setting it aside for some days. A gentle heat may also be applied. The red liquor must be then separated by the filter, and decomposed by the addition of carbonate of soda, when a fine red precipitate will be obtained. Or, the reddish brown coloring matter of a decoction of madder may be first separated by acetate of lead, and then the rose red color with alum. Or, madder tied up in a bag is boiled in water ; to the decoction, alum is added, and then potash. The precipitate should be washed with boiling water, till it ceases to tinge it yellow; and it is then to be dried. The following process merits a preference : • e ^n Diffuse 2 pounds of ground madder in 4 quarts of water, and after a maceration of 10 minutes, strain and squeeze the grounds in a press. Repeat this maceration, &c. twice upon the same portion of madder. It will now have a fine rose color. It must then be mixed with 5 or 6 pounds of water and half a pound of bruised alum, and heated upon a water bath for 3 or 4 hours, with the addition of water, as it evaporates, aftex which the whole must be thrown upon a filter cloth. The liquor which passes is to be filtered through paper, and then precipitated by carbonate of potash. If the pota?h be added m three "successive doses, three different lakes will be obtained, of successively diminishing beauty. The precipitates must be washed till the water comes off colorless. Bhie lakes are hardly ever prepared, as indigo, Prussian blue, cobalt blue, and ultra^ marine, answer every purpose of blue pigments. Green lakes are made by a mixture of yellow lakes with blue pigments ; but chrome mellows mixed with blues produce almost all the requisite shades of green. LAM IN ABLE is said of a metal which may be extended by passing between steel or hardened (chilled) cast-iron rollers. For a description of metal rolling presses, see Iron and Mint ; and For a table of the relative laminability of metals, see Ductility. LAMIUM ALBUM, or the dead nettle, is said by Leuchs to afford in its leaves a greenish-yellow dye. The L. purpureum dyes a reddish-gray with salt of tin, and a greenish tint with iron liquor. LAMPS differ so much in principle, form, and construction, as to render their descrip- tion impossible, as a general subject of manufacture. In fact, the operations of the lampisl, like those of the blacksmith, cabinet-maker, cooper, coppersmith, tinman, turner, &c., belong to a treatise upon handicraft trades. I shall here, however, intro- duce a tabular view of the relative light and economy of the lamps most genei-ally known. I Kind of Lamps. Intensity of light during Mean of 7 hours. Consump- tion per hour in grammes. Light from 100 parts of oil. 1 hour 2 liMurs 3 hours 4 hours 5 hours 6 hours 1. Mechanical lamp of Carcel 100 42 238 2. Fountain lamp, ^ and a chimney > with flat wick ) 3. Dome argand 4. Sinumbra lamp 5. Do. with fountain above 100 103 102 100 98 90 95 90 98 72 83 70 97 61 81 52 96 42 78 41 96 34 66 32 125 31 56 85 11 26-714 37-145 43 113 116 150 197 6. Do. with another beak - - . 100 97 95 92 89 86 41 18 227 7. Girard's hydrostatic lamp - - - 101 96 84 81 76 70 63-66 34-714 182 8. Thilorier'sorPar- ) ke!'s hydrosta- > 106 103 100 94 92 90 107-66 51-143 215 tic lamp - ) / %Q LAMPS. LAMP OF DAVY. tl ( ' * ^ In the above table, for the purpose of comparing the successive degrees of intensity 100 represents the mean intensity of light during the first hour. The quantity of oUcw ^ZilZr?Z!^ ^^^^ 'a ^\°^"^^,^» ""^ ^H grains each. The last column expresses the l^^^l ^ght produced with a like consumption of oil, which was in all cases 100 grammes, oee Candles. The foUowing table of M. Peclet is perhaps more instructive :— r Nature of the light. Intensity. 1. Mechanical lamp 2. Flat-wick mechan. do. 3. Hemispherical dome lamp - 4. Sinumbra lamp Do. with a lateral foun- tain or vase - Do. with a fountain above - - . Girard's hydrostatic lamp - _ _ Thilorier's or Parker's lamp - » . Candle, 6 in lb. Do. 8 in lb. Do. 6 with smaller wick - . . Wax candle, 5 in lb. Sperm candle, do. 14. Stearine candle, do. 15. Coal gas - - - 116. Oil gas - - _ 5. 6. 7. 8. 9. 10. 11. 12. 13. 100 12-05 31-0 85 41 90 63*66 107-66 10-66 8-74 7-50 13-61 14-40 14-30 127 127 Consump- tion per hour in grammes. 42 11 26-714 43 18 43 34-71 51-143 8-51 7-51 7-42 8-71 8-92 9-35 136 litres 136 do. Cost per kilo- gramme. francs. 1-40 1-40 1-40 1-40 1-40 1-40 1-40 1-40 1-40 1-40 2-40 7-60 7-60 6-OU of light per hour. cents. 5-8 15 3-7 60 2-5 6-0 4-8 Fat pro- ducing the same light. Cost per hour. grammes. 42 88 86-16 50-58 I I 43-90 47-77 54-52 cents. 5-8 12-3 120 70 61 6-6 7-6 I 7-1 47-5 6-6 1-2 70-35 9-8 1-0 85-92 12-0 1-7 98-93 23-7 5-7 6404 48 6 5-8 61-94 47-8 5-5 65-24 37-1 50 107 litres 3-9 5-0 30 3-9 J .J^% ^IS^K""^ *^^ mechanical lamp is greatly over-rated relatively to that of iras Th^ Th"/wH- "'"''' V ^'t ^V^"^'' greate/ than of the latter, l/London ^ ^' ofTnrnPnfl ^ ^°Tk ^^ Under this title, is tho construction of lamps for bu;ning spirits of turpentine m the place of the fat oils which alone have been in use from th^^ZlJ remote ages down to the present time. Several patents have Recently be^n obtared for these lamps, under the fantastic title of Camphine ; one bHlr Wm^^^^^^ and another by Messrs. Rayner and Carter, as the in vention oil woiking mker-R^ forr^^n. f'^? ^''" employed by the proprietors of these patents to eSne the Pe^ Ireroc^^l's':!!!^"^"^^^^ ^^°^P^' ^ ^^- --^ *^« ^-o -P-ta drawn up^'LTn eauaUo ve'rt^^^rf^'f^'' i"^"^ ^'^^ '^ "*°^*^'^ brilliancy, without smoke, emits a light equal to very nearly twelve wax or sperm candles of three or four to the pound and m so doing It consumes exactly one imperial pint of spirits of turpentkH value she i^on/h Tf^ '° ^''^ ^r'^ ' ^T'^ '^^ «°^* P«^ ^^"^ ^^' « ligl^t equal?otenuch candles IS one halfpenny; whereas that from wax candles would be nearly sixpence fr^^ 8pe,^aceti ditto fivepence; from stearine ditto, fourpence; from Palmer's sn^^^ ^^^:^^\^'::^^:Z'^i fromtallowmoulds,li<.; from sp^rt^,!! inTatl? ^:ii:^^:;;^V^^^ '-'-' «^^^^ ^e=-^ed hues^trJletthl gr^a'llw^Sef than thrnf T ""^''^'^ ""TS ^'^^* '« ^^^"^^^ ^^ *^« ^^^^^ ^amp, is to be LcounteV?^^^^^^^ tT\^^ ^'' ^'^'\^ ^"^"^T ^^ "^""^ ^^^^^^^^^^^ ' * circumstance pentLe aTfat oHs tT. «n; f '\"' ^/!^"?^«al/o°^Position between spirits of tur- penune ajia lat oils. The spirits consist entirely of carbon and hydrotren - in the nro- 8^^322 nart of n ^''°'''* '^r^"'' *"^ Hi of ^the latter, in 100 ^^^akd thet ^ot sume 328 parte of oxygen; whereas sperm and other unctuous oils consist of 78 narL of carbon. 11* of hydrogen, and lOi of oxygen, in 100 parts; and Jherconsume only 287-2 of oxygen, in being burnt; because the oxygen already present m the oil neti. Jralizes 2^ parts of the cSrbon and 0-4 of the hydrogen, thus leaving only 85* parta of ihe combustible elements for the atmosphere to burn. For this reason. 87* parts by weiffM of spirits of turpentine, will consume as much oxygen as 100 parts of sperm oil- and will afford, moreover, a more vivid light, because they contain no oxide, as fat oils do which serves to damp the combustion. In the spirits of turpentine, the affinity of ite elements for oxygen is entire, whereas in fat oil the affinity is partially ne^utral- ized by the oxides it contains ; somewhat as the flame of spirits of wine is weakened bv their dilution with water. , . , xi *. " Among the many applications of science to the useful arts, for which tiie present age is so honorably distinguished, few are more meritorious than the Camphine lamps, bv which we can produce a snow-white flame from the cleanly, colorless spirit* of tur- pintine— a pure combustible fluid, in place of the smeary rank oils which contain a seventh part of incombustible matter. Being so rich in hydro-carbon, "^e spirits re- auire peculiar artifices for complete consumption and the development of their full power of yielding light without smoke or smell. This point of perfection seems to be happily attained by the invention of the two parallel flat ringd in the Paragon lamjfc a lareer and smaller, forming a cone round the margin of the wick, which cause a rapid revel beratiori of the air against the flame : thus consuming every particle of volatilized vapor and adding energy to the luminous undulations. Hence the patent Paragon lamp in full action emits a light equal to that of sixteen wax-candles three to the pound, but of better quality, approaching in purity to that of the sun-beam —there- fore capable of displaying natural and artificial objects in their true colors. But these lamps are very apt to smoke. , . ., -n x. r^- "One imperial pint of rectified spirits of turpentine, value 6(i retail, will burn for twelve hours in this lamp, affording all the time the illumination of eleven wax-candlea. " The Paragon Camphine lamp is attended with no danger in use. "The Cost, as compared with other Lamps or Candles, is as follows: viz.— PER HOUB. Paragon Camphine Lamp (equal to 11 wax candles), less than One Halfpenny. Wax Candles -------- Spermaceti ditto "."'"'"' Adamantean Wax (Stearic Acid) - - - - - Palmer's Spread-Wick Candles . - - - - Cocoa Nut Candles ------- Moulds (Tallow) ------- . Carcel'a Lamp, with Sperm oil - - - - " Bee Illumination, Cost of. for a description of an excellent oil lamp. LAMP OF DAVY consists of a common oil lamp, surmounted with a covered 839 cylinder of wire gauze, for transmitting light to the miner >^ithout endangering the kindling of the atmosphere of fire-damp which may surround him; because carbureted hydrogen, m passmg through the meshes of the cylindric cover, gets cooled by the con- ducting power of the metallic gauze, below the point of its accension. -• on v r The apertures in the gauze should not be more than 1 .iOtti of an inch square. Since the fire damp is not inflamed by ignited wire, the thickness of the wire is not of importance, but wire from l-40lh to l-60th of an inch in diameter is the most convenient. The cage or cylinder should be made by double joinings, the gauze being folded over in such a manner as to leave no apertures. Q When it is cylindrical, it should not be more than two inches m diameter ; because In larger cylinders, the combustion of the fire- damp renders the top inconveniently hot ; a double top is always a proper precaution, fixed f or f of an inch above the first top. See fig* 839. The gauze cylinder should be fastened to the lamp by a screw b, fig. 840. of four or five turns, and fitted to the screw by a tight ring. All joinings in the lamp should be made with hard solder ; as the secu- rity depends upon the circumstance that no aperture exists in the appa- ratus larger than in the wire-gauze. 6*d 6f 4i 3* 4f 2f 2" 840 22 LAMP OF DAVY. The parts of the lamp are, 1. The brass cistern a, d,fig, 840, which contains the oil. It is pierced at one side of the centre with a vertical narrow tube, nearly filled with a wire which is recun'ed above, at the level of the burner, to trim the wick, by acting on the lower end of the wire e with the fingers. It is called the safety-trimmer. 2. The rim b is the screw neck for fixing on the gauze cylinder, in which the wire- gauze cover is fixed, and which is fastened to the cistern by a screw fitted to h. 3. An aperture c for supplying oil. It is fitted with a screw or a cork, and communi- cates with the bottom of the cistern by a tube at/. A central aperture for the wick. 4. The wire-gauze cylinder, y/g. 839, which should not have less than 625 apertares to the square inch. 6. The second top, £ of an inch above the first, surmounted by a brass or copper plate, to which the ring of suspension may be fijced. It is covered with a wire cap in the figure. 6. Four or six thick vertical wires, g' g' g' g', joining the cistern below with the lop plate, and serving as protecting pillars round the cage, g is a screw-pin to fix the cover, so that it shall not become loosened by accident or carelessness. The oil-cistern fig. 840 is dr^wn upon a larger scale Ihan/g. 839, to show its minuter parts. When the wire-gauze safe-lamp is lighted and introduced into an atmosphere gradually mixed with fire-damp, the first effect of the fire-damp is to increase the length and size of the flame. When the inflammable gas forms so much as l-12th of the volume of th- air, the cylinder becomes filled with a feeble blue flame, while the flame of the wick ^ appears burning brightly within the blue flame. The light of the wick augments till the fire-damp increases to l-6th or I-5th, when it is lost in the flame of the fire-damp, which in this case fills the cylinder with a pretty strong light. As long as any eaplosire mixture of gas exists in contact with the lamp, so long it will give light ; and when it is extinguished, which happens whenever the foul air constitutes so much as l-3d of the volume of the atmosphere, the air is no longer proper for respii alion ; for though animal life will con- tinue where flame is extinguished, yet it is always with suflering. By fixing a coil of platinum wire above the wick, ignition may be nraintained in the metal when the lamp itself is extinguished ; and from this ignited wire the wick may be again rekindled, on carrying it into a less inflammable atmosphere. « We have frequently used the lamps where the explosive mixture was so high as to heat the wire-gauze red-hot ; but on examining a lamp which has been in constant use for three months, and occasionally subjected to this degree of heat, I cannot perceive that the gauze cylinder of iron wire is at all impaired. I have not, however, thought it pru- dent, in our present state of experience, to persist in using the lamps under such circum- stances, because I have observed, that in such situations the particles of coal dust floating in the air, fire at the gas burning within the cylinder, and fly ofl' in small luminous sparks. This appearance, I must confess, alarmed me in the first instance, but experience soon proved that it was not dangerous. " Besides the facilities aflorded by this invention to the working of coal-mines abound- ing in fire-damp, it has enabled the directors and superintendents to ascertain, with thf utmost precision and expedition, both the presence, the quantity, and correct situation of the gas. Instead of creeping inch by inch with a candle, as is usual, along the galleries of a mine suspected to contain fire-damp, in order to ascertain its presence, we walk firmly on with the safe-lamps, and, with the utmost confidence, prove the actual state of the mine. By observing attentively the several appearances upon the flame of the lamp, in an examination of this kind, the cause of accidents which happened to the most experienced and cautious miners is completely developed ; and this has hitherto been in a great meas- ure matter of mere conjecture. « It is not necessary that I should enlarge upon the national advantages which must necessarily result from an invention calculated to prolong our supply of mineral coal, because I think them obvious to every reflecting mind ; but I cannot conclude without expressing my highest sentiments of admiration for those talents which have developed the properties, and controlled the power, of one of the most dangerous elements which human enterprise has hitherto had to encounter." — See Letter to Sir H. Davy, in Journal of Science, vol. i. p. 302, by John Buddie, Esq., generally and justly esteemed one of the most scientific coal-miners in the kingdom. Mr. Buddie, in a letter dated 21st August, 1835, which is published in Dr. Davy's life of his brother Sir Humphrey, says : — " In the evidence given in my last examination before a committee of the House of Commons, I stated that after nearly twenty years' experience of * the Davy' with from 1000 to 1500 lamps in daily use, in all the variety of circumstances incidental to coal mining, without a single accident having happened which could he atiributed to LAMPATES. a defect in its principle, or even in the rules for its practical application, as laid down by Sir Humphrey--I maintained that ' the Davy' approximated perfection, as nearly as any instrument of human invention could be expected to do. We have ascertained distinctly that the late explosion did not happen in that part of the mine where l^^^ Davys were used. They were all found in a perfect stale after the accident— many of them in Uie hands of the dead bodies of the suflierers." LAMP-BLACK. See Black. . . , ^ •. .. • t LAMPATFS and LAMPIC ACID. When a spirit of wine lamp has its cotton wick surmounted with a spiral coil of platinum wire, after lighting it for a little, it may be blown out, without ceasing to burn the alcohol ; for the coil continues ignited, and a cur- rent of hot vapor continues to rise, as long as the spirit lasts. This vapor was first con- densed and examined by Professor Daniell, who called it lampic acid. It has a peculiar, strondy acid, burning taste, and a spec. grav. of 1-015. It possesses in an emment tie- gree the property of reducing certain metallic solutions ; such as those of platinum, goia, and silver. The lampates may be prepared by saturating the above acid with the alkaline and earthy carbonates. - . . v v „„j LAPIDARY, Jrt of. The art of the lapidary, or that of cutting, polishing, and engraving gems, was known to the ancients, many of whom have left admirable specimens of their skill. The Greeks were passionate lovers of rings and engraved stones ; and the most parsimonious among the higher classes of the Cyrenians are said to have worn rings of the value of ten minse (about 30Z. of our money.) By far the greater part of the antique gems that have reached modern times, may be considered as so many models lor terming the taste of the student of the fine arts, and for inspiring his mind with correct ideas ol what is trulv beaulifuL With the cutting of the diamond, however, the ancients were unacquainted, and hence they wore it in its natural state. Even in the middle ages, this art was still unknown ; for the four large diamonds which enrich the clasp ol the impenal mantle of Charlemagne, as now preserved in Paris, are uncut, octahedral crystals. But the art of working diamonds was probably known in Hindostan and China, in very remote periods. After Louis de Berghen's discovery, in 1476, of polishing two diamonds by their mutual attrition, all the finest diamonds were sent to Holland to be cut and polished by the Dutch artists, who long retained a superiority, now no longer admitted by the lapida- ries of London and Paris. o v . The operation of gem cutting is abridged by two methods ; 1. by cleavage ; i. by cut- ting oflf slices with a fine wire, coated with diamond powder, and fixed m the stock of a hand-saw. Diamond is the only precious stone which is cut and polished with diamond powder, soaked with olive oil, upon a mill plate of very soft steel. Oriental rubies, sapphires, and topazes, are cut with diamond powder soaked with olive oil, on a copper wheel. The facets thus formed are afterwards polished on another cop- per wheel, with tripoli, tempered with water. Emeralds, hyacinths, amethysts, garnets, agates, and other softer stones, are cut at a Jead wheel, with emery and water; and are polished on a tin wheel with tripoli and water, or, still better, on a zinc wheel, with putty of tin and water. v i p v ^ The more tender precious stones, and even the pastes, are cut on a mill-wheel of hard wood, with emery and water; and are polished with tripoli and Water, on another wheel of hard wood. , v v i. ♦ Since the lapidary employs always the same tools, whatever be the stone which he cuts or polishes, and since the wheel discs alone vary, as also the substance he uses with them, we shall describe, first of all, his apparatus, and then the manipulations for diamond-cut- ting, which are applicable to every species of stone. The lapidary's mill, or wheel, is shown in perspective in fig. 841. It consists of a strong frame made of oak carpentry, with tenon and mortised joints, bound together with strong bolts and screw nuts. Its form is a parallelepiped of from 8 to 9 feet long, by from 6 to 7 high ; and about 2 feet broad. These dimensions are large enough to con- lain two cutting wheels alongside of each other, as represented in the figure. Besides the two sole bars b b, we perceive «% D, E, F, G. m the breadth, 5 cross bars, . , . . The two extreme bars c and g, are a part of Ihr frame-work, and serve to bind it. The two cross-bars d and f, carry each in the middle of their length, a piece of wood as thick as themselves, but only A\ inches long (see fig, 842), joined solidly bv mortises and tenons with that cross bar, as well a£ / tfK» \ 24 LAPIDARY. with the one placed opposite on the other parallel face. These two pieces are called summers (lintels) ; the one placed at d is the upper ; the one at f, the lower. In Jig. 842 this face is shown inside, in order to explain how the mill wheel is placed and supported. The same letters point out the same objects, both in the preceding and the followins; figures. In each of these summers a square hole is cut out, exactly opposite to the other; in which are adjusted by friction, a square piece of oak a, a, Jig, 842. whose extremities are perforated with a conical hole, which receives the two ends of the arbor h of the wheel i, and forms its socket. The square bar is adjusted at a conve- nient height, by a double wooden wedge b b. The cross bar in the middle e supports the table «: c, a strong plank of oak. It is pierced with two large holes whose centres coincide with the centre of the conical holes hollov/- ed out at the end of the square pins. These holes, of about 6 inches diameter each, are intended to let the arbor pass freely through, bearing its respective wheel. (See one of these holes at i, in Jig. 846 below.) Each wheel is composed of an iron arbor h, Jig. 843. ffrinding-wheel i, which diilers in substance according of a to 848 circumstances, as already stated, and of the pulley J, furnish- ed with several grooves (see Jig. 844), which has a square fit upon the arbor. The arbor carries a collet d, on which are 4 iron pegs or pins that enter into the wheel to fasten it. The wheel plate, of which the ground plan is shown at k, is hollowed out towards its centre to half its thickness ; when 844 it is in its position on the arbor, as indicated in Jig. 844. a washer or ferrule of wrought iron is put over it, and secured in its place by a double wedge. In Jig. 844 the wheel-plate is represented in section, that the connexion of the whole parts may be seen. A board g (see fig. 841 and^g. 849), about 7| inches high, is fixed to the part of the frame opposite to the side at which the lapidary works, and it prevents the substances made use of in the cutting and polishing, from being thrown to a dis- tance by the centrifugal force of the wheel-plate. Behind this apparatus is mounted for each grinding-plate, a large wheel l (see fig. 841), similar to a cutlei-'s, but placed horizontally. This wheel is grooved round its circumfer- ence to receive an endless cord or band, which passes round one of the grooves of the pulley J, fixed below the wheel-plate. Hence, on turning the fly-wheel l, the plate re- volves with a velocity relative to the velocity communicated to the wheel l, and to the dif- ference of diameter of the wheel l and the pulley J. Each wheel l, is mounted on an iron arbor, with a crank (see m. Jig. 846.) The lower pivot of that arbor h is conical, and turns in a socket fixed in the floor. The great wheel l rests on the collet i, furnished with its 4 iron pins, for securing the con- nexion. Above the wheel an iron washer is laid, and the whole is fixed by a double wedge, which enters into the mortise I, Jig. 845. Fig. 846. exhibits a ground-plan view of all this assemblage of parts, to explain the structure of the machine. Every thing that stands above the upper summer-bar has been suppressed in this representation. Here we see the table c c ; the upper summer m ; the one wheel-plate /, the other having been removed to show that the endless cord does not cross ; the two large wheels l l, present in each machine, the crank bar n, seen separate in Jig. 847. which serves for turning the wheel l. 1^1 847 f^^?=:^ n P—Iug^ N tos \ ■V LAPIDARY. 25 bent round at the point n, to embrace the stud s ; the second, p g, is of the same breadth and thickness as the first; and the third is adjusted to the latter with a hinge joint, at the point 9, where they are both turned into a circular form, to fn^^'-f^th^ crank m. When all these pieces are connected, they are fixed at the proper lengths by the buckles or SGuare rings i 1 1, which embrace these pieces as is shown m fig. 846. T\e stud I seen in Jig. 847. is fixed to the point v by a wedge key upon the arm f, represented separately, and In perspective injig. 848. The laborer ^eizmg the two up- right pegs or handles x x, by the alternate forward and backward motion of h^s arm he communicates the same motion to the crank rod, which transmits it to the crank of the arbor m, and impresses on that arbor, and the wheel which it bears, a rotatorj' move- ment. 849 This bar is formed of 3 iron plates, n, o; V»q ; and ^, r ; (/ig. 847.) T^he firsi i» Fig. 849. shows piece-meal and in perspective, a part of the lapidary s wheel-min. There we see the table c c, the grind-plate i, whose axis is kept in a vertical Position b, the two square plugs a a, fixed into the two summers by the wedges bb. On the two sWefof the wheVplate we perceive an important instrument called a dtaZ, which serve, to hold lie stone durin" the cutting and polishing. This instrument has received lately mpo tin aSeto^^^^^ described in fig. 850. The lapidary holds this instrument n his hand, he rests it upon the iron pins u u fixed in ^le table, lest he should be affected by the velocity of the revolving wheel-plate. He loads it sometimes with weights e, e, to make it take better hold of the grinding plate. ^ ^ /. „ • • ^ One of the most expert lapidaries of Geneva works by means of the following improved me^hanbm, of his own invention, wl.ereby he cuts and pohshes the facets with extreme iptTiilaritv. converting it into a true dial. ^ , - , • » le^uiariiy, c n e S ^^^ ^^^^^ ^j^.^ j^nprovement. Each of the two jaws bears a large conchoidal cavity, into which is fitted a brass ball, which carries on its upper part a tube e, to whose extremity is fixed a dial-plate//, en^'raved with several concentric circles, divided into equal parts, like the toothed-wheel cutting engine-plate, according to the number of facets to be placed in each cutting range. The tube receives with moderate friction the handle of the cement rod, which is fixed at the proper point by a thumb-screw, not shown in the figure, being con- cealed by the vertical limb d, about to be described. A needle or index g, placed with a square fit on the tail of the cement rod, marks by its point the divisions^on the dial plate //. On the side m n of the jaw a, there isSxed by two "screws, a limb d, forming a quadrant whose centre is supposed to be at the centre of he ball. This quadrant is divided as usual into 90 degrees, whose highest point is marked 0, and the lowest would mark about 70 ; for the remainder of the arc do^vn to 90 is concealed by the jaw. The two graduated plates are used as follows :- When the cement rod conceals zero or of the limb, it is then ^'e^ical and serves to cut the table of the brilliant ; or the point opposite to it, and parallel to the table. On making it slope a little, 5 degrees for example, all the facets will now lie m the same zone, provided that the inclination be not allowed to var5^ On turning round the cement rod the index g marks the divisions, so that by operating on the circle with 16 divisions, stopping for some time at each, 16 facets will have been formed, of perfect eaualitv, and at equal distances, as soon as the revolution is completed. Diamonds are cut at the present day in only two modes; into a rose diamond, and a brilliant. AVe shall therefore confine our attention to these two forms. The rose diamond is flat beneath, like all weak stones, whUe the upper face nse* jilo a dome, and is cut into facets. Most usually six facets are put on the cenual region, te LAPIDARY. which are in the form of triangles, and unite at their summiti ; their bases abut upon another range of triangles, which being set in an inverse position to the preceding, present theii- bases to them, while their summits terminate at the sharp margin of the stone. The latter triangles leave spaces between them which are likewise cut each into two facets. By this distribution the rose diamond is cut into 24 facets; the surface cf the diamond being divided into two portions, of which the upper is called the crown, and that forming the contour, beneath the former, is called dcnlette (lace) by the French artists. According to Mr. Jeffries, in his Treatise on Diamonds, the regular rose diamond is formed by inscribing a regular octagon in the centre of the table side of the stone, and bordering it by eight right-angled tiiangles, the bases of which correspond with the sides of the octagon; beyond these is a chain of 8 trapeziums, and another of 16 triangles. The collet side also consists of a minute centra] octagon, from every angle of which pro- ceeds a ray to the edge of the jirdle, forming the whole surface into 8 trapeziums, each of which is again subdivided by a salient angle (whose apex touches the girdle) into one irregular pentagon and two triangles. To fashion a rough diamond into a brilliant, the first step is to modify the faces of the original octahedron, so that the plane formed by the junction of the two pyramids shall be an exact square, and the axis of the crystal precisely twice the length of one of the sidts of the square. The octahedron being thus rectified, a section is to be made parallel to >,he common base or girdle, so as to cut oft' 5 eighteenths of the whole height from the upper pyramid, and 1 eighteenth from the lower one. The superior and larger plane thus produced is called the table, and the inferior and smaller one is called the collet ; in this state it is termed a complete square table diamond. To convert it into a brilliaut, two triangular facets are placed on each side of the table, thus changing it from a square to an octagon ; a lozenge-shaped facet is also placed at each of the four corners of the table, and another lozenge extending lengthwise along the whole of each side of the ori- ginal square of the table, which with two triangular facets set on the base of each lozenge, completes the whole number of facets on the table side of the diamond ; viz., 8 lozenges, and 24 triangles. On the collet side are formed 4 irregular pentagons, alter- nating with as many irregular lozenges radiating from the collet as a centre, and bordered by 16 triangular facets adjoining the girdle. The brilliant being thus completed, is set with the table side uppermost, and the collet side implanted in the cavity made to receive the diamond. The brilliant is always three times as thick as the rose diamond. In France, the thickness of the brilliant is set oflT into two unequal portions ; one third is reserved for the upper part or table of the diamond, and the remaining two thirds for the lower part or collet {culasse). The table has eight planes, and its circumference is cut into facets, of which some are triangles, and others lozenges. The collet is also cut into facets called pavilions. It is of consequence that the pavilions lie in the same order as the upper facets, and that they correspond to each other, so that the symmetry be perfect, for otherwise the play of the light would be false. Although the rose-diamond projects bright beams of light in more extensive proportion often than the brilliant, yet the latter shows an incomparably greater play, from the difler- ence of its cutting. In executing this, there are formed 32 faces of diflerent figures, and inclined at diflerent angles all round the table, on the upper side of the stone. On the collet (culasse) 24 other faces are made round a small table, which converts the culasse into a truncated pyramid. These 24 facets, like the 32 above, are diflerently inclined and present diflerent figures. It is essential that the faces of the top and the bottom corres- pond together in sufficiently exact proportions to multiply the reflections and refractions, so as to produce the colors of the prismatic spectrum. The other precious stones, as well as their artificial imitations, called pastes, are cut in the same fashion as the brilliant ; the only diflerence consists in the matter constitulii.g 851 852 the wheel plates, and the grinding and polishing powders as already stated. In cutting the stones, they are mounted on the cement- rod B,fis^. 851, whose stem is set upright in a socket placed PI [I N . " ,_ ~~1 ill the middle of a sole piece at a, which receives the stem I nT^^^^^^Pj of the cement-rod. The head of the rod fills the cup of A. y ^\ ~\ T \ -^ melted alloy of tin and lead is poured into the head of the cement-rod, into the middle of which the stone is immediately plunged ; and whenever the solder has become solid, a por- tion of it is pared off" from the top of the diamond, to give the pyramidal form shown in the figure at b. There is an instrument employed by the steel polishers for pieces of clock work, and by the manufacturers of watch-glasses for polishing their edges. It consists of a solid oaken table. Jig. 852. The top is perforated with two holes, one for passing through the pulley and the arbor of the wheel-plate b, made either of lead or of hard LAPIDARY. 27 wood according to circumstances ; and the other c fcj receiving the upper pari of the arbor of the large pulley d. The upper pulley of the wheel plate is supported by an iron prop E, fixed to the table by two wooden screws. The inferior pivots of the two pieces are supported by screw-dockets, working in an iron screw-nut sunk into the summer-bar F The le"^s of the table are made longer or shorter, according as the workman chooses to stand or''sit at his employment. Emery with oil is used for grinding down, and tin- putty or colcothar for polishing. The ^»orkman lays the piece on the flat of the wheel- plate with one hand, and presses it down with a lump of cork, whUe he turns round the handle with the other hand. , ^ . ^ , ,tt _^ The Sapphire, Ruby, OneiUal Amethyst, Oriental Emerald, and Oriental Topaz, are gems next in value and hardness to diamond ; and they all consist of nearly pure alumina or clay with a minute portion of iron as the coloring matter. The foUowing analyses show the affinity in composiUon of the most precious bodies with others in little relative estimation. Sapphire. Corundum Stone. Emery. Alumina or clay Silica - Oxyde of iron - Lime - - - 98-5 0-0 1-0 0-5 89-50 5-50 1-25 0-00 86-0 30 4*0 0-0 100-0 96-25 93-0 i Salamstme is a variety which consists of small transparent crystals, generally six-sided prisms, of pale reddish and bluish colors. The corundum of Batlagammana is fre^iuently found in large six-sided prisms : it is commonly of a brown color, whence it is called by the natives curuwiu gallc, cinnamon stone. 'I'he hair-brown and reddish-brown crystals are called adamantine spar. Sapphire and salamstone are chiefly met with in secondary repositories, as in the sand of rivers, &c., accompanied by crystals and grains of octahe- dral iron-ore and of several species of gems. Corundum is found in imbedded crystals m a rock, consisting of indianite. Adamantine spar occurs in a sort of granite. The finest varieties of sapphire come from Pegu, where they occur in the Capelan mountains near Syrian. Some have been found also at Hohenstein in Saxony, Bilin in Bohemia, Puy in France, and in several other countries. The red variety, the ruby, is most highly valued. Its color is between a bright scarlet and crunson. A perfect ruby above 3h carats is more valuable than a diamond of the same weight. If it weigh 1 carat, it is worth 10 guineas; 2 carats, 40 guineas; 3 carats, 150 guineas; 6 carats, above 1000 guineas. A deep colored ruby, exceeding 20 carats in weight, is generally called a carbuncle ; of which 108 were said to be in the throne of the Great Mogul, wei'^hin*' from 100 to 200 carats each ; but this statement is firobably incorrect. The lar4st oriental ruby known to be in the world was brought from China to Prmce Gar- gann, governor of Siberia. It came afterwards into the possession of Prmce MenzUtotf, and constitutes now a jewel in the imperial crown of Russia. . ^ «^ , .. A ^ood blue sapphire of 10 carats is valued at 50 guineas. If it weighs 20 carats, its value" is 200 'guineas ; but under 10 carats, the price may be estimated by multiplying the square of its weight in carats into half a guinea ; thus, one of 4 carats would be worth 42 X ^ G =8 guineas. It has been said that the blue sapphire is superior m hardness tothe^'red, but this is probably a mistake arising from confounding the corundum ruby with the <;pinelle ruby. A sapphire of a barbel blue color, weighing 6 carats, was dis- posed of in Paris by public sale for 70^. sterling ; and another of an indigo blue, weighing 6 carats and 3 grains, brought 60/. ; both of which sums much exceed what the preceding rule assigns, from which we may perceive how far fancy may go in such matters. The sapphire of Brazil is merely a blue tourmaline, as its specific gravity and inferior hard- ness show. White sapphires are sometimes so pure, that when properly cut and polished they have been passed for diamonds. /. /^ • The vellow and green sapphires are much prized under the names of Oriental topax and emerald. The specimens which exhibit all these colors associated in one stone ore hiffhlv valued, as they prove the mineralogical identity of these varieties. Besides these shades of color, sapphires often emit a beautiful play of colors, or chatoiement, when held in diff'erent positions relative to the eye or incident light ; and some likewise present star-like radiations, whence they are called star-stones or astenas ; sending forth 6 or even 12 rays, that chari^e their place with the position of the stone. This property, so remarkable in certain blue sapphires, is not, however, peculiar to these gems. It seems to belong to transparent minerals which have a rhomboid for their / 28 LAPIDARY. LEAD. 29 nucleus, and arises from the combination of certain circumstances in their cutting and structure. Lapidaries often expose the light-blue variety of sapphire to the action of fire, in order to render it white and more brilliant ; but with regard to those found at Expailly, in France, fire deepens their color. 3. Chrysoberyly called by Hauy, Cymophane, and by others. Prismatic corundum, ranks next in hardness to sapphire, being 8-5 on the same scale of estimation. Its specific grav- ity is 3*754. It usually occurs in rounded pieces about the size of a pea, but it is also found crystallized in many forms, of which 8-sided prisms with 8-sided summits are per- haps the most frequent. Lustre vitreous, color asparagus green, passing into greenish- white and olive-green. It shows a bluish opalescence, a light undulating, as it were, in the stone, when viewed in certain directions ; which property constitutes its chief at- traction to the jeweller. When polished, it has been sometimes mistaken for a yellow diamond ; and from its hardness and lustre is considerably valued. Good specimens of it are very rare. It has been found only in the alluvial deposites of rivers, along with other species of gems. Thus it occurs in Brazil, along with diamonds and prismatic to- paz ; also in Ceylon. Its constituents are alumina, 68-66 ; glucina, 16-00 ; silica, 6-00 ; protoxyde of iron, 4-7 ; oxyde of titanium, 2-66 ; moisture, 0-66 ; according to Seybert's analysis of a specimen from Brazil. It is difficultly but perfectly fusible before the blow- pipe, with borax and salt of phosphorus. In composition it dilfers entirely from sapphire, or the rhombohedral corundum. 4. Spinelle Ruby, called Dodecahedral corundum, by some mineralogists, and Balas ruby, by lapidaries. Its hardness is 8. Specific gravity, 3-523. Its fundamental form is the hexahedron, but it occurs crystallized in many secondary- forms : octahedrons, tetra- hedrons, and rhombohedrons. Fracture, conchoidal ; lustre, vitreous ; color, red, passing into blue and green, yellow, brown, and black ; and sometimes it is nearly white. Red spinelle consists of alumina, 74-5 ; silica, 15-5; magnesia, 8-25; oxyde of iron, 1.5; lime, 0-75. Vauquelin discovered 6-18 per cent, of chromic acid in the red spinelle. The red varieties exposed to heat become black and opaque ; on cooling, they appear first green, then almost colorless, but at last resume their red color. Pleonaste is a variety which yields a deep green globule with borax. Crystals of spinelle from Ceylon have been observed imbedded in limestone, mixed with mica, or in rocks containing adularia, which seem to have belonged to a primitive district. Other varieties like the pleonaste occur in the drusy cavities of rocks ejected by Vesuvius. Crystals of it are often found in diluvial and alluvial sand and gravel, along with true sapphires, pyramidal zircon, and other gems ; as also with octahedral iron ore, in Ceylon. Blue and pearl-gray varieties occur in Siidennannland, in Sweden, im- bedded in granular limestone. Pleonaste is met with also in the diluvial sands of Cey- lon. Clear and finely colored specimens of spinelle are highly prized as ornamental stones. When the weight of a good spinelle exceeds 4 carats, it is said to be valued at half the price of a diamond of the same weight. M. Brard has seen one at Paris which weighed 215 grains. 5. Zircon or Hyacinth. Its fundamental form is an isosceles 4-sided pjTamid ; and the secondary forms have all a pyramidal character. Fracture, conchoidal, uneven; lustre, more or less perfectly adamantine colors, red, brown, yellow, gray, green, white ; which, with the exception of some red tints, are not bright. Hardness, 7-5. Specific gravity, 4-5. Zircon and hyacinth consist, according to Klaproth, of almost exactly the same constituents ; namely, zirconia, 70 ; silica, 25 ; oxyde of iron, 5. In the white zirconia there is less iron and more silica. Before the blowpipe the hyacinth loses its color, but does not melt. The brighter zircons are often worked up into a brilliant form, for ornamenting watch cases. As a gem, hyacinth has no high value. It has been often confounded with other stones, but its very great specific gravity makes it to be readily recognised, 6. Topaz. The fundamental form is a scalene 4-sided p>Tamid ; .but the secondary forms have a prismatic character ; and are frequently observed in oblique 4-sided prisms, acuminated by 4 planes. The lateral planes of the prism are longitudinally striated. Fractuie, conchoidal, uneven ; lustre, vitreous; colors, white, yellow, green, blue; gen- erally of pale shades. Hardness, 8 ; specific gravity, 3-5. Prismatic topaz consists, ac- cording to Berzelius, if alumina, 57*45; silica, 34-24; fluoric acid, 7*75. In a strong heat the faces of crystallization, but not those of cleavage, are covered with small blis- ters, which however immediately crack. With borax, it melts slowly into a transparent glass. Its powder colors the tincture of violets green. Those crystals which possess different faces of crystallization on opposite ends, acquire the opposite electricities on being heated. By friction, it acquires positive electricity. Most perfect crystals of topaz have been found in Siberia, of green, blue, and white colors, along with beryl, in the Uralian and Altai mountains, as also in Kamschatka ; in Brazil, where they generally occur in loose crjstals, and pebble forms of bright yel- t 4 low colors ; and in Mucla, in Asia Minor, in pale straw-yellow regular crystals. They are also met with in the granitic detritus of Cairngorm, in Aberdeenshire. The blue varieties are absurdly called oriental aquamarine^ by lapidaries. If exposed to heat, the Saxon topaz loses its color and becomes white ; the deep yellow Brazilian varieties as- sume a pale pink hue ; and are then sometimes mistaken for spinelle, to which, however, they are somewhat inferior in hardness. Topaz is also distinguishable by its double refractive properly. Tavemier mentions a topaz, in the possession of the Great Mogul, which weighed 157 carats, and cost 20,000Z. sterling. There is a specimen in the museum of naturalhistory at Paris which weighs 4 ounces 2 gros. Topazes are not scarce enough to be much valued by the lapidary. 7. Emerald and Beryl are described in their alphabetical places. Emerald loses \ts lustre by candle-light ; but as it appears to most advantage when in the company of dia- monds, it is frequently surrounded with brilliants, and occasionally with pearls. Beryl is the aquamarine of the jewellers, and has very little estimation among lapidaries. 8. Garnet. See this stone in its alphabetical place. 9. Chrysolite, called Peridot, by Haiiy ; probably the topaz of the ancients, as our topax was their clir>'solite. It is the softest of the precious stones, being scratched by quarts and the file. It refracts double. 10. QttcWr, including, as s\ih-s^ecies, Jlmeihyst, Rock-crystal , Rose-guani, Prase, or Chrysoprase, and several varieties of calcedony, as Cat's-eye, Plasma, Chrysoprase, Onyx, Sardmiyx, &c. Lustre, vitreous, inclining sometimes to resinous; colors, very various; fracture, conchoidal ; hardness, 7 ; specific gravity, 2-69. 11. Opal, or uncleavable quartz. Fracture, conchoidal; lustre, vitreous or resinous i colors, white, yellow, red, brown, green, gray. Lively play of light ; hardness, 5-5 to 6-5; specific gravity, 2-091. It occurs in small kidnej-shaped and stalactitic shapes, and large tuberose concretions. The phenomena of the play of colors in precious opal has not been satisfactorily explained. It seems to be connected with the regular Structure of the mineral. Hydrophane, or oculis mundi, is a variety of opal without transparency, but acquiring it when immersed in water, or in any transparent fluid. Precious opal was found by Klaproth to consist of silica, 90 ; water, 10 ; which is a very curious combination. Hungary has been long the only locality of precious opal, where it occurs near Caschau, along with common and semi-opal, in a kind of porphyry. Fine varieties have, however, been lately discovered in the Faroe islands ; and most beau- tiful ones, sometimes quite transparent, near Gracias a Dios, in the province of Hondu- ras, America. The red and yellow bright colored varieties of fire-opal are found near Zimapan, in Mexico. Precious opal, when fashioned for a gem, is generally cut with a convex surface ; and if large, pure, and exhibiting a bright play of colors, is of consid- erable value. In modern times, fine opals of moderate bulk have been frequently sold at the price of diamonds of equal size : the Turks being particularly fond of them. The estimation in which opal was held by the ancients is hardly credible. They called it Paideros, or Child beautiful as love. Nonius, the Roman senator, prefeired banishment to parting with his favorite opal, which was coveted by Mark Antony. Opal which ap- pears quite red when held against the light, is called girasol by the French ; a name also given to the sapphire or corundum asterias or star-stone. 12. Turquois or Calaite. Mineral turqucis occurs massive ; fine-grained, impalpable ; fracture, conchoidal ; color, between a blue and a green, soft, and rather bright ; opaque ; hardness, 6 ; spec, grav., 283 to 3-0. Its constituents are alumina, 73 ; oxyde of copper, 4-5; oxyde of iron, 4; water, 18; according to Dr. John. But by Berzelius, it consists of phosphate of alumina and lime, silica, oxydes of copper, and iron, with a little water. It has been found only in the neighborhood of Nichabour in the Khorassan, in Persia ; and is very highly prized as an ornamental stone in that country. There is a totally dif- ferent kind of turquois, caUed bone turquois, which seems to be phosphate of lime colored with oxyde of copper. When the oriental stone is cut and polished, it forms a pleasing gem of inferior value. Malachite, or mountain green, a compact carbonate of copper, has been substituted sometimes for turquois, but their shades are different. Malachite yields a green streak, and turquois a white one. 13. Lapis lazuli is of little value, on account of its softness. LAZULITE (Eng. and Fr. ; Lazulith^ Germ.); is a blue vitreous mineral, crystalliz- ing in rhoraboidal dodecahedrons; spec. grav. 2-76 to 2-94; scratches j^lass; affords a little water by calcination; fusible into a white glass; dissolves in acids with loss of color; solution leaves an alkaliue residuum, after being treated with carbonate of ammonia, filtered, evaporated, and calcined. It consist? of silica, 35"8 ; alumina, 84 8 ; soda, 23-2; sulphur, S'l ; carbonate of lime, 3'1. This beautiful stone affords the native ultramarine pigment, which was very costly till a mode of makiug it artificially was lately discovered. See Ultramarine. LEAD. {Plomb, Fr. ; Blei, Germ.) This is one of the metals most anciently known / 30 LEAD. Si being mentioned in the books of Moses. It has a gray blue color, with a bright metal- lie lustre wlien newly cut, but it becomes soon tarnished and earthy looking in the air. Its texture is close, wiUiQut perceptible cleavage or appearance of structure ; the specific gravity of common lead is 11-352; but of the pure metal, from 11-38 to 11-44. It is very malleable and ductile, but soft and destitute of elasticity; fusible Ht 61-2° Fahr. by Crighton, at 634° by Kupfer, and crystallizable on cooling, into octahedrons implanted into each other so as to form an assemblage of four-sided pyramids. There are four oxydes of lead. 1. The suboxyde, of a grayish-blue color, which forms a kind of crust upon a plate of lead long exposed to the air. It is procured in a perfect state by calcining oxalate of lead in a retort ; the dark gray powder which re- mains, is the pure suboxyde. 2. The protoxyde is obtained by exposing melted lead to the atmosphere, or, more readily, by expelling the acid from the nitrate of lead by heat in a platinum crucible. It is yellow, and was at one time prepared as a pigment by cal- cining lead ; but is now supereeded by the chromate of this metal. Litharge is merely this oxyde in the form of small spangles, from having undergone fusion ; it is more or less contaminated with iron, copper, and »ometimes a little silver. It contains likewise some carbonic acid. The above oxyde consists of 104 of metal, and 8 of oxygen, its prime eriuivalent being 1 12, upon the hydrogen scale ; and it is the base of all the salts of lead. 3. The plumbeous suroxyde of Berzelius, the sesquioxyde of some British chem- ists, is the well known pigment called red lead or minium. It consists of 100 parts of metal and 10 of oxygen. 4. The plumbic suroxyde of Berzelius, or the peroxyde of the British chemists, is obtained by putting red lead in chlorine water, or in dilute nitric acid. It is of a dark brown, almost black color, which gives out oxygen when heated, and be- comes yellow oxyde. It kindles sulphur when triturated with it. This oxyde is used by the analytical chemist to separate, by condensation, the sulphurous acid existing in a gaseous mixture. Among the ores of lead some have a metallic aspect ; are black in substance, as well as when pulverized ; others have a stony appearance, and are variously colored, with usually a vitreous or greasy lustre. The specific gravity of the lalCer ores is always less than 5. The whole of them, excepting the chloride, become more or less speedily black, with sulphureted hydrogen or with hydrosulphurets ; and are easily reduced to the metallic state upon charcoal, with a flux of carbonate of soda, after they have been properly roasted. They diffuse a whitish or yellowish powder over the charcoal, which, according to the manner in which the flame of the blowpipe is directed upon it, becomes yellow or red ; thus indicating the two characteristic colors of the oxydes of lead. We shall not enter here into the controversy concerning the existence of native lead, which has been handled at length by M. Brongniart in the Dictimnaire des Sciences Nat- urelles, article Plomb, Mineralogie. The lead ores most interesting to the arts are : — 1. Galena, sulphuret of lead. This ore has the metallic lustre of lead with a crystal- line structure derivable from the cube. When heated cautiously at the blowpipe it is decomposed, the sulphur flies oflf, and the lead is left alone in fusion ; but if the heat be continued, the colored surface of the charcoal indicates the conversion of the lead into its oxydes. Galena is a compound of lead and sulphur, in equivalent proportions, and therefore consists, in 100 parts, of 86f of metal, and 13 § of sulphur, with which numbers the analysis of the galena of Clausthal by Westrumb exactly agrees. Its specific grav- ity, when pure, is 7'56. Its color is blackish gray, without any shade of red, and its pow- der is black, characters which distinguish it from blende or sulphuret of zinc. Its struc- ture in mass is lamellar, passing sometimes into the fibrous or granular, and even compact. It is brittle. The specular galena, so called from its brightly polished aspect, is remark- able for forming the sUckensides of Derbyshire — thin seams, which explode with a loud noise when accidentally scratched in the mine. The argentiferous galena has in general all the external characters of pure galena. The proportions of silver vary from one fifth part of the whole, as at Tarnowitz, in Sile- sia, to three parts in ten thousand, as in the ore called by the German miners Weisgiilti- gerz ; but it must be observed, that whenever this lead ore contains above 5 per cent, of silver, several other metals are associated with it. The mean proportion of silver in galena, or that which makes it be considered practically as an argentiferous ore, because the silver may be profitably extracted, is about two parts in the thousand. See Silvkr. The above rich silver ores were first observed in the Freyberg mines, called Himmels- furst and Bcschertgluck, combined with sulphuret of antimony; but they have been no- ticed since in the Hartz, in Mexico, and several other places. The antimonial galena (Boumonite) exhales at the blowpipe the odor peculiar to anti niony, and coats the charcoal with a powder partly white and partly red. It usually cob tains some arsenic. LEAD. 31 4 2. The Se^eniuret of lead resembles galena, but its tint is bluer. Its chemical char acters are the only ones which can be depended on for distinguishing it. At tlie blowpipe it exhales a very perceptible smell of putrid radishes. Nitric acid liberates the selenium. When heated in a tube, oxyde of selenium of a carmine red rises along with selenic acid, white and deliquescent. The specific gravity of this ore varies from 6*8 to 7*69. 3. Native minium or red lead has an earthy aspect, of a lively and nearly pure red color, hut sometimes inclining to orange. It occurs pulverulent, and also compact, with a fracture somewhat lamellar. When heated at the blowpipe upon charcoal, it is readily reduced to metallic lead. Its specific gravity varies from 4-6 to 8-9. Ihis ore IS rare. 4. Plomb'gomme. — This lead ore, as singular in appearance as in composition, is of a dirty brownish or orange-yellow, and occurs under ihe form of globular or gum-like concretions. It has also the lustre and translucency of gum ; with somewhat of a pearly aspect at times. It is harder than fluor spar. It consists of oxyde of lead, 40 ; alumina, 37 ; water, 18-8 ; foreign matters and loss, 4-06 ; in 100. Hitherto it has been found only at Huelgoet, near PouUaouen, in Brittany, covering with its tears or small concretions the ores of white lead and galena which compose the veins of that lead mine. 5. White lead, carbonate of lead.— This ore, in its purest state, is colorless and trans, parent like glass, with an adamantine lustre. It may be recognised by the following characters : — Its specific gravity is from 6 to 6*7 ; it dissolves with more or less ease, and with effervescence, in nitric acid ; becomes immediately black by the action of sulphureted hydrogen, and melts on charcoal before the blowpipe into a button of lead. According to Klaprolli, the carbonate of Leadhills contains 82 parts of oxyde of lead, and 16 of car- bonic acid, in 98 parts. This mineral is tender, scarcely scratches calc-spar, and breaks easily with a waved conchoidal fracture. It possesses the double refracting properly in a very high degree ; the double image being very visible on looking through the flat faces of the prismatic crystals. Its crystalline forms are very numerous, and are referrible to the oclahedron, and the pyramidal prism. 6. Vitreous lead, or sulphate of lead. — This mineral closely resembles carbonate of lead ; so that the external characters are inadequate to distinguish the two. But the following are sufficient. When pure, it has the same transparency and lustre. It does not eflervesce with nitric acid ; it is but feebly blackened by sulphureted hydros en ; it first decrepitates and then melts before the blowpipe into a transparent glass, which be- comes milky as it cools. By the combined action of heat and charcoal, it passes first into a red pulverulent oxyde, and then into metallic lead. It consists, according to Klaproth, of 71 oxyde of lead, 25 sulphuric acid, 2 waler, and 1 iron. That specimen was from Anglesea ; the Wanlockhead mineral is free from iron. The prevailing form of crjstal- lization is the rectangular octahedron, whose angles and edges are variously modified. The sulphato-carbonate, and sulphato tri-carbonale of lead, now called Leadhillite, are rare minerals which belong to this head. 7. Phosphate of lead. — This, like all the combinations of lead with an acid, exhibits no metallic lustre, but a variety of colors. Before the blowpipe upon charcoal, it melts into a globule externally crystalline, which, by a continuance of the heat, with the addition of iron and boracic acid, aifords metallic lead. Its constituents are 80 oxyde of lead, 18 phos- phor c acid, and 1-G muriatic acid, according to Klaproth's analysis of the mineral from Wanlockhead. The constant presence of muriatic acid in the various specimens exam- ined is a remarkable circumstance. The crystalline fonns are derived from an obtuse rhomboid. Phosphate of lead is a little harder than white lead ; it is easily scratched, and its powder is always gray. Its specific gravity is 6'9. It has a vitreous lustre, some- what adamantine. Its lamellar texture is not very distinct ; its fracture is wavy, and it i.v easily frangible. The phosphoric and arsenic acids being, according to M. Milscher- lich, isomoi-phous bodies, may replace each other in chemical combinations in every pro- portion, so that the phosphate of lead may include any proportion, from the smallest fmn tion of arsenic acid to the smallest fraction of phosphoric acid, thus graduating indefi- nitely into arseniate of lead. The yellowish variety indicates, for the most part, the presence of arsenic acid. 8. Muriate of lead. Horn-lead^ or murio-carlonate. — This ore has a ijale yellow color, is reducible to metallic lead by the agency of soda, and is not altered by the hydrosul- phurets. At the blowpipe it melts first into a pale yellow transparent globule, with salt of phosphorus and oxyde of copper; and it manifests the presence of muriatic acid by a bluish flame. It is fragile, tender, softer than carbonate of lead, and is sometimes almost colorless, with an adamantine lustre. Spec, srrav., 606. Its constituents, according to Berzelius, are lead, 25-84 ; oxyde of lead, 57-07; carbonate of lead, 6-25; chlorine, 8'-84; silica, 1-46; water, 0-54 ; in 100 parts. The carbonate is an accidental ingrojient, not ' -rih' 83 LEAD. beinc: in equivalent proportion. Klaproth found chlorine, 13-67; lead, 39-98 ; oxyde ol lead," 22-57 ; carbonate of lead, 23-78. 9. Jrsmiate of lead. — Its color of a pretty pure yellow, bordering slightly on the greenish, and its property of exhaling by the joint action of fire and charcoal a very distinct arsenical odor, are the only characters which distinguish this ore from the phos- phate of lead. The form of the arseniate of lead, when it is crystallized, is a prism with six faces, of the same dimensions as that of phosphate of lead. "When pure, it is redu- cible upon charcoal, before the blowpipe, into metallic lead, with the copious exhalation of arsenical fumes ; but only in part, and leaving a crystalline globule, wiien it contains any phosphate of lead. The arseniate of lead is tender, friable, sometimes even pulve- rulent, and of specific gravity 5-04. That of Johann-Georgenstadt consists, according to Rose, of oxyde of lead 77*5; arsenic acid 12-5} phosphoric acid 7-5, and muriatic acid 1-5. 10. Red lead, or Ckromate of had. — This mineral is too rare to require consideration in the present work. 11. Plornb vauqtcelinite. Chromaie of icad and copper. 12. Yellow lead. Molybdate of lead. 13. Tungstate of lead. Having thus enumerated the several species of lead ore, we may remark, that galena is the only one which occurs in sufficiently great masses to become the object of mining and metallurgy. This mineral is found in small quantity among the crystalline primitive rocks, as granite. It is however among the oldest talc-schists and clay slates, that it usu- ally occurs. But galena is much more abundant among the transition rocks, being its principal locality, where it exists in interrupted beds, masses, and more rardy in veins. The blackish transition limestone is of all rocks that which contains most galena ; as at Pierreville in Normandy ; at Clausthal, Zellerfeldt, and most mines of the Harz ; at Fahlun, in Sweden ; in Derbyshire and Northumberlauid, &c. In the transition graywacke of the south of Scotland, the galena mines of Leadhills occur. The galena of the primitive formations contains more silver than that of the calcareous. The principal lead mines at present worked in the world, are the following: ]. Poullaouen and Huelgoet near Carhaix in France, department of Finisterre, being veins of galena, which traverse a clay slate resting upon granite. They have been known for ipwards of three centuries ; the workings penetrate to a depth of upwards of 300 yards, and in 1816 furnished 500 tons of lead per annum, out of which 1034 pounds avoirdu- pois of silver were extracted. 2. At Villeforte and Viallaz, department of the Lozere, are galena mines said to produce 100 tons of lead per annum, with 400 kilogrammes of silver (880 lbs. avoird.). 3. At Pezey and Macot, to the east of Moutiers in Savoy, a galena mine exists in talc-schist, which has produced annually 200 tons of lead, and about 600 kilogrammes of silver (1320 lbs. avoird.). 4. The mine of Vedrin, near Namur in the Low Countries, is opened upon a vein of galena, traversing compact lime- stone of a transition district ; it has furnished 200 tons of lead, from which 385 pounds avoird. of silver were extracted. 5. In Saxony the galena mines are so rich in silver as to make the lead be almost overlooked. They are enumerated under silver ores. 6. The lead mines of the Harz have been likewise considered as silver ores. 7. Those of Bley- berg in the Eifel are in the same predicament. 8. The galena mines of Bleybcrg and Vilfach in Carinthia, in compact limestone. 9. In Bohemia, to the south-west cf Prague. 10. The mines of Joachimsthal, and Bleystadt, on the southern slope of the Erzgcbirgc, produce argentiferous galena. 11. There are numerous lead mines in Spain, the most important being in the granite hills of Linares, upon the southern slope of the Siena Morer.a, and in the district of the small town of Canjagar. Sometimes enormous masses of galena are extracted from the mines of Linares. There are also mines of galena in Catalonia, Grenada, Murcia, and Abneria, the ore of the last locality being generally poor in silver. 12. The lead mines of Sweden are very argentiferous, and worked chiefly with a view to the silver. 13. The lead mines of Daouria are numerous and rich, lying in a transition limestone, which rests on primitive rocks ; their lead is neglected on account of the silver. 14. Of all the countries in the world, Great Britain is that which annually produces the fi:realest quantity of lead. Accord^" ig to M. Villefosse, in his Richesse Minerale, published in 1810, we had furnished every .M^r 12,500 tons of lead, whilst all the rest of Europe taken together, did not produce so much ; but from more recent documents, that estimate seems to have been too low. Mr. Taylor has rated the total product of the United Eong- dora per annum at 31,900 tons, a quantity fully 2| times greater than the estimate of Villefosse (see Conybeare and Phillips's Geology, p. 354). Mr. Taylor distributes this product among the different districts as follows : — LEAD. 33 V Wales, (Flintshire and Denbighshire) - . - - , Scotland, (in transition graywacke) - - . Durham, Cumberland, and Yorkshire, (in carboniferous lime)' Derbyshire, (probably in carboniferous lime) - - - . Shropshire - - - _ . ._ Devon and Cornwall, (transition and primitive" rocks) - '• Tons. 7,500 2,800 19,000 1,000 800 800 Total - - - . . Ol Qfto YoTk fur„°ir„fVv.* Cumberland, and the adjacent parts of the bounties of DuZm and York, furnish of themselves nearly three-fifths of the total product Derbyshire vZ, ir"elns^in'Mlrr/™tf '*'• •^" ?°™"''" ""J D-onsGire the lead o e i 7oZ ^^^Sz^-^^^=^^^^^^. - SfoeT-n" th^etr Sfit ifr.r^rni:i«t=^^^^^^^^ Beaumont alone, yeldmg 10,000. In 1847, the totil produce was ^ follows'^ England Wales - Ireland Scotland Isle of Man Total Lead Ore. Tons. 69,614i 18,147j 2,251 1,159 2,575 Lead. 83,747 Tons. 89,507 i 12,294 1,380 822| 1,699 55,703 The English lead-miners distinguish three different kinds of deposites of lead ore- [^^""TZ' PlP';'''^^ '-^^d fat-veins The English word vein corresponds to the FrS IlMh?^' -t TfK- ""^^^ "il^ °^ '^ indifferently in England and France, to inSe all the deposites of this ore, addmg an epithet to distinguish the different forms thus ^■ake veins are true veins in the geological acceptation of the word ve[n ; V^Sn. S masses usually very narrow, and of oblong shape, most frequently paral el fo the pla^ thele strata ^ ' ^^'^ •^^'-'^"'" ^^ ^^^" ^^ of ores interposed in the middle ^T Rake-veins are the most common form in which lead ore occurs in Cumberland. They are i" general narrower in the sandstone which covers the limestone, than in \he calcareous beds. A thickness of less than a foot in the former, becomes sudde^y 3 or 4 feet m the latter; in the rich vein of Hudgillburn, the thickness is 17 feet L the Great h^ncstcme, while it does not exceed 3 feet in the overlymg Watersill or sandTtone This influence exercised on the veins by the nature of the enclosing rock, is instructive rt determines at the same time almost uniformly their richness in lead ore, an obse^atlon TNorwav" Th r 'k'T '.'' '^ '^'" '°""^T' ^^^^^^^^^ ^" ^^^ vein^ of Kongsbi^ h J;.T^* The Cumberland vems are constantly richer, the more powerful they are in the portions which traverse the calcareous rocks, than in the beds of sandstone and^'ore for Jh^e ve ' '^^ -'"'i^r ' '"'H . ^'- ^' """""^ ^^ ^'^ ^«^^ ^^11^ P^' (- «ol^d 'sla'y Say^ tL unlr^^,. include any ore; it is commonly filled with a species of potter's earth most Tfh .? '^^''l^^' • '^ ^^'^ '"^ ^^''^'^^ "'^''^ productive than the lower ones. In ??h! r^ r fu ""'"i^'' ^^^ ^'^'''' ^""^^ "°^ '^°^^«^ ti^l lately below the fifth calcareous bed (the four-fathom Imiestone), which is 307 yards beneath the mDl-stone grit! and as the of h ""^^^^^^ ''^ >"^^^ \^"^n^ ij' 1^ f«»o^^ that the thickness o? the p^' or tne ground where the veins are rich m lead does not in general exceed ^oo vards It TrSTo threw'rh 'T '^^" ''^" °^^"^'^" ^^^ neighbourhood oSon Mo'oMown Tder tl mil' Z^^^ ^°"«° limestone, which is 418 yanls they hate blen fonow^H i. ' T^/Tr ''""' immediately above the whin-siU ; and'thal whTchl onlv 83 vn^^^^^^^ ^''^ limestone stratum, as high as the grindstone siU, tTSess of the ZmbJr '^^ "^T stratum of mill-stone grit; so that in the totS asserted that \etdv^.^[^''"K ^^^^^^^lon there is more than 336 yards. It has been sidls^'blin^'not T^f'^T °t ^ '''^" ^^^"' P^^^^ commonly in the points where/Its t^ Xnone?ur.//i ^^'''^^^^^^ ^^^ ^^ ^°<^>^ '* ^^^ its impoverishment LuS Vol U '^^'^'"'''^ ^"'^ *^^ ^^^ V ''^^'*''' "^^y- '^^^ ^"^'^^« which m^ 'I III M LEAD. frequently accompany the galena, are carbonate of lime, fluate of lime, snlphate of bar>ta, quartz, and pyrites. The pipe-veins (amas in French) are seldom of great length ; but some have a con- siderable width ; their composition being somewhat similar to that of the rake-veins. They meet commonly in the neighborhood of the two systems, sometimes being in evident communication together ; they are occasionally barren ; but when a wide pipe-vein is metalliferous, it is said to be very productive. The Jlat veins, or .sirata veins, seem to be nothing else than expansions of the matter of the vein between the planes of the sirata ; and contain the same ores as the veins in their vicinity. When they are metalliferous, they are worked along with the adjacent rake vein ; and are productive to only a certain distance from that vein, unless they get enriched by crossing a rake vein. Some examples have been adduced of advantageous workings in flat veins in the great limestone of Cumberland, particularly in the mines of Coalcleugh and Nenthead. The rake veins, however, furnish th« greater part of the lead which Cumberland and the adjacent counties send every year into the market. Mr. Forster gives a list of 165 lead mines, which have been formerly, or are now, worked in that district of the kingdom. The metalliferous limestone occupies, in Derbyshire, a length of about 25 miles from north-west to south-east, under a very variable breadth, which towards the south, amounts to 25 miles. Castleton to the north, Buxton to the north-west, and Matlock to the south-east, lie nearly upon its limits. It is surrounded on almost all sides by the mill-stone grit which covers it, and which is, in its turn, covered by the coal strata. The nature of the rocks beneath the limestone is not knoAvn. In Cumberland the metalliferous limestone includes a bed of trap, designated under the name of whinsill. In Derbyshire the trap is much more abundant, and it is thrice interposed between the limestone. These two rocks constitute of themselves the whole mineral mass, through a thickness of about 550 yards, measuring from the millstone grit ; only in the upper portion, that is near the millstone grit, there is a pretty considerable thickness of ar- gillo-calcareous schists. Four great bodies or beds of limestone are distinguishable, which alternate with three masses of trap, called toadstone. The lead veins exist in the calcareous strata, but disappear at the limits of the toadstone. It has now been ascertained, however, that they recur in the limestone underneath. LEAD IN THE Exhibition.— Sopwith, Thomas, F. R. S., Ac. AUenheads, Northumber- land, inventor and producer. Specimens of lead ores and associated minerals, with examples of the various stages of progress from their being excavated in the mine and carried through the several de- partments of washing and smelting, until furnished and ready for the market in the form of a cake of silver and a pig or piece of lead known as W. B. lead. The specimens of minerals usually associated with lead ores are collected from va- rious mines, and are fitted together in a separate ease, under the direction of the ex- hibitor, by Messrs. Cain and Wallace of Nenthead, and otheis. The general arrangement of the strata in which these ores and minerals are found b exhibit~ed by a section of part of the lead mining district belonging to Wentworth Blackett Beaumont, Esq., at Allenheads, in the county of Northumberland, and from whose mines the specimens of lead ores and examples of process during conversioa into lead and silver are taken ; and a further illustration of the geographical struc- ture of this part of England is given by an isometrical plan and section by the exhibit- or, showing a considerable tract of mining ground in the manor of Alston Moor, in the county of Cumberland. • v- u The principal phenomena of mineral veins and displacement of the strata in which lead ore is obtained in the north of England are shown by dissected models, invented by the exhibitor, and examples of the finished products are contained in a separate case, fiom Mr. Beaumont's smelt-mills, under the direction of his agent, Mr. Thomas SteeL This collection, the general nature of which is here briefly indicated, is mtended to illustrate the geological position and usual products of the north of England lead mines. The following is the order of the five several portions, and which are more particu- larly described under these several heads in the sequel. 1. Sections of strata at Allenheads and Alston. 2. Models to illustrate mineral veins, or, is provWed broad, and a Uttle mised behM o„ ,h f ' '"'?'' '']"?'' ""='' '' » A^' »™ « feel walls theoreto£Sedisied On h/r^<^^ ""'"P'^ '"'•o"'' ^-y ^"^^l cast-iron plate is laid 7 f^t iJ^„ t- ? v *'?"'' "."^ 7""' " ^"^ >>"<• stone slab, or ofTnirtH:i:,^Tz'Ti°'"XhTe^"''lr' cylinders,, x,.;??. 853, and of two pair, cylinders of each of the thr^e n,i . altogetlier for crushing the ore. The two means cf two tSothtl wheds asTt m. «" siT""''"'"^'^'"^""-. '"''"^ ■''^«"™. ^^ lucu wneeis, as at m, fig. 854, upon the shall of every cylinder, which 853 g54 41 ^ /a -"•^ retirlr^VrVp^nf ^he ^^^£^ b, a single water-wheel, of which placed in the prolongation of the shift of Z!wi?r ?"^, ""^ ^^^ ^"^^^ cylindera is toothed wheer geered with the toXdwhpl.i' "I"'"'' '^'."'' ^^'^^"^ ^ ^^^^^-^--^^ smooth cylinders. Above the fl^tid p^ n!? /u ^''^^ "P^'^ ^^^ ^"^« «^ t^« «f the «opt3r!heiroontentsi„eoY?Lr,rrtr:^l,r:-^^^^^^^^^ of their bottom. Below the hopper there is a small bucket called a shoe, into which the ore is shaken down, and which throws it without ceasing upon the cylinders, in conse- quence of the constant jolts given it by a crank-rod i {Jig. 854) attached to it, r.nd moved by the teeth of the wheel m. Tlie shoe is so regulated, that too much ore can never fiill upon the cylinders, and obstruct their movement. A small stream of water is likewise led into the shoe, which spreads over the cylinders, and prevents them from growing hot The ore, after passing between the fluted rollers, falls upon the inclined planes n, n, which turn it over to one or other of the pairs of smooth rolls. These are the essential parts of this machine ; they are made of iron, and the smooth ones are case-hardened, or chilled, by being cast in iron moulds. The gudgeons of both kinds move in brass bushes fixed upon iron supports fe, made fast by bolts to the strong wood-work basis of the whole machine. Each of the horizontal bars has an oblong slot, at one of whose ends is solidly fixed one of the plummer-blocks or bearers of one of the cylinders /, and in the rest of the slot the plummer-block of the other cylinder g slides; a construction which permits the two cylinders to come into con- tact, or to recede to such a distance from each other, as circumstances may require. The moveable cylinder is approximated to the fixed one by means of the iron levers x x, which carry at their ends the weights p, and rest upon wedges m, which may be slidden npon the inclined plane n. These wedges then press the iron bar o, and make it ap- proach the moveable cylinder by advancing the plummer block which supports its axis. When matters are so arranged, should a very large or hard piece present itself to one of the pairs of cylinders, one of the rollers would move away, and let the piece pass without doing injury to the mechanism. Besides the three pairs of cylinders which constitute essentially each crushing machines there is sometimes a fourth, which serves to crush the ore when not in large fragments, for example, the chats and cuttings (the moderately rich and poorer pieces), produced by the first sifting with the brake sieve, to be presently described. The cylinders com- posing that accessor}' piece, which, on account of their ordinary use, are called chats-rollers, are smooth, and similar to the rollers z 2, and z' z'. The one of them is usually placed upon the prolongation of the shaft of the water-wheel, of the side opposite to the princi- pal machine ; and the other, which is placed alongside, receives its motion from the first, by means of toothed wheel-work. The stamp mill is employed in concurrence with the crushing cylinders. It ser^'es par- ticularly to pulverize those ores whose gangue is too hard to yield readily to the rollers, and also those which being already pulverized to a certain degree, require to be ground still more finely. The stamps employed in the neighborhood of Alston Moor are moved by water wheels. They are similar to those described under Tin. Proper sifting or jigging apparatus. — The hand sieve made of iron wire meshes, of various sizes, is shaken with the two hands in a tub of water, the ore vat, being held sometimes horizontally, and at others in an inclined position. This sieve is now in general use only for the cuttings that have passed through the grating, and which though not poor enough to require finer grinding, are too poor for the brake sieve. When the workman has collected a sufficient quantity cf these smaller pieces, he puts them in his round hand sieve, shakes it in the ore vat with much rapidity and a dexterous toss, till he has separated the very poor portions called cuttings, from the mingled parts called ckats^ as well as from the pure ore. He then removes the first two qualities, wilh a shcf t-iron scraper called a limp, and he finds beneath them a certain portion of ore which he reckons to be pure. The brake sieve is rectangular, as well as the cistern in which it is agitated. The meshes are made of strong iron wire, tliree eighths of an inch square. This sieve is sust- pended at the extremity of a forked lever, or brake, turning upon an axis by means of two upright arms about 5 feet long, which are pierced with holes for connecting them with bolts or pins, both to the sieve-frame and to the ends of the two branches of the lever. These two arms are made of wrought iron, but the lever is made of wood ; as it receives the jolt. ' A child placed near its end, by the action of leaping, jerks it smartly Up and down, so as to shake effectually the sieve suspended at the other extremity. Each jolt not only makes the fine parts pass through the meshes, but changes the rela- tive position of those which remain on the wires, bringing the purer and heavier pieces eventually to the bottom. The mingled fragments of galena, and the stony substances called chats lie above them ; while the poor and light pieces called cuttings, are at top. These are first scraped off by the limp, next the mixed lumps, or chats, and lastly the pure ore, which is carried to the bing heap. The cuttings are handed to a particular class of workmen, who by a new sifting, divide them into mere stones, or second cuttings, and into mixed ore analogous to chats. The poor ore, called chats, is carried to a crushing machine, where it is bruised between two cylinders appropriated to this purjwse under the name of chats rollers; after which it is sifted afresh. During the sifting many parcels of small ore and stony sub / 43 LEAD. LEAD. 48 II stances pass through the sieve, and accumulate at the bottom of the cistern. When it is two thirds filled, water is run slowly over it, and the sediment called smitham is taken out, and piled up in heaps. More being put into the tub, a child lifts up the smitham^ and lays it on the sieve, which retains still on its meshes the layer of fine ore. The sifter now agitates in the water nearly as at first, from time to time removing with the limp the lighter matters as they come to the surface ; which being fit for washing only in boxes, are called buddler^s offaly and are thrown into the budlk hole. Mr. Petherick, the manager of Lanescot and the Fowey Consol mines, has contrived an ingenious jigging machine, in which a series of 8 sieves are fixed in a stationary cir- cular frame, connected with a plunger or piston working in a hollow cylinder, whereby a body of water is alternately forced up through the crushed ore in the sieves, and then left to descend. In this way of operating, the indiscriminate or premature passage of the finer pulverulent matter through the meshes is avoided, because a regulated stream of water is made to traverse the particles up and down. This mode has proved profitable in washing the copper ores of the above mentioned copper mines. Proper washing apparatus. — For washing the ore after sifting it, the running buddle already described is employed, along with several chests or buddies of other kinds. 1. The trunk huddle is a species of German chest (see Mf.tallurgy and Tin) com- posed of two parts ; of a cistern or box into which a stream of water flows, and of a large tank with a smooth level bottom. The ore to be trunkcd being placed in the box, the workman furnished with a shovel bent up at its sides, agitates it, and removes from time to time the coarser portions ; while the smaller are swept off by the water and deposited upon the level area. 2. The stirring buddle, or chest for freeing the schlamms or slimy stuff from clay, is analogous to the German chests, and consists of two parts; namely, 1. a trough which receives a stream of water through a plug hole, which is tempered at pleasure, to admit a greater or less current ; 2. a settling tank with a horizontal bottom. The metallic slime being first floated in the water of the trough, then flows out and is deposited in the tank j the purest parts falling first near the beginning of the run. 3. The nicking buddle is analogous to the tables called dormantes or jumelles by the French miners. See Metallurgy. They have at their upper end a cross canal or spout, equal in length to the breadth of the table, with a plug hole in its middle for admitting the water. Alongside of this channel there is a slightly inclined plank, called nicking board, corresponding to the head of the iwin table, and there is a nearly level plane below. The operation consists in spreading a thin layer of the slime upon the nicking board, and in running over its surface a slender sheet of water, which in its pro- gress is subdivided into rills, which gradually carry off the muddy matters, and strew them over the lower flat surface of the tank, in the order of their density. 4. The dolly tub or rinsing bucket, Jig. 855, has an upright shaft which bears the vane or dolly a b, turned by the winch handle. This apparatus serves to bring into a state of suspension in water, the fine ore, already nearly pure ; the separation of the metallic particles from the earthy ones by repose, being promoted by the sides of the tub being struck frequently during the subsidence. 5. Slime pits. — In the several operations of cleansing ores from mud, ia grinding, and washing, where a stream of water is used, it is impossible to prevent eome of the finely attenuated portions of the galena called sludge, floating in tfte watei; from being carried ofl' with it. Shm£ pits or labyrinths, called buddle holes in Derbyshire, are employed to collect that matter, by receiving the water to settle, at a little distance from the place of agitation. These basins or reservoirs are about 20 feet in diameter, and from 24 to 40 inches deep. Here the suspended ore is deposited, and nothing but clear water is allowed to escape. The workmen employed in the mechanical preparation of the ores, are paid, in Cum berland, by the piece, and not by day's wages. A certain quantity of crude ore is deliv- ered to them, and their work is valued by the bing, a measure containing 14 cwts. of ore ready for smelting. The price varies according to the richness of the ore. Certain quali- ties are washed at the rate of two and sixpence, or tliree shillings the bing; while others are worth at least ten shillings. The richness of the ore varies from 2 to 20 bings of galena per shift of ore ; the shift corresponding to 8 wagon loads. 1. The cleansing and sorting of the ores are well performed in Cumberland. These operations seem however to be inferior to the cleansing on the grid steps, grilles a gradin^ of Saxony (See Mktallurgy), an apparatus which in cleaning the ores, has the advan- tage of grouping them in lots of different qualities and dimensions. 2. The breaking or bruising by means of the crushing machine, is much more expedi- tious than the Derbyshire process by buckers ; for the machine introduces not only great economy into the breaking operation, but it likewise diminishes considerably the loss of galena ; for stamped ores may be often subjected to the action of the cylinders without ^:;g:;;.:-' waste while a portion of them would have been lost with the water that runs from the stamp' mill. The use of these rollers may therefore be considered as one of the happiest innovations hitherto made in the mechanical preparation of ores. 3. The hake sieves appear to be preferable to the hand ones. 4. The system of washing used in Cumberland differs essentially from that of Brit- tany. The slime pits are constructed with nmch less care than in France and Germany. They never present, as in these countries, those long windings backwards and forwoids, whence they have been called labyrinths ; probably because the last deposites, which are washed with profit in France and Germany, could not be so in Cumberland. There is reason to believe, however, that the introduction of biuke tables {tables a seccusscs, see Metallurgy) would enable deposites to be saved, which at present run to waste in England. j . t • 5. From what we have now said about the system of washing, and the basins of de- posite or settling cisterns, it may be inferred that the operation followed in Cumberland is more expeditious than that used in Brittany, but it furnishes less pure ores, and occasions more considerable waste ; a fact sufficiently obvious, since the refuse stuff at Poullaouen is often resumed, and profitably subjected to a new preparation. We cannot however ven- ture to blame this method, because in England, fuel being cheap, and labor dear, there may possibly be more advantage in smelting an ore somewhat impure, and in losing a little galena, than in multiplying the number of washing processes. 6. Lastly, the dolly tub ought to be adopted in all the establishments where the galena is mixed with much blende (sulphuret of zinc) : for schlich (metallic slime) which appears very clean to the eye, gives off a considerable quantity of blende by means of the dolly tub. While the vane is rapidly whirled, the sludge is gradually let down into the revolv- ing water, till the quantity is sufficiently great. Whenever the ore is thoroughly dissem- inated in the liquid, the dolly is withdrawn. The workmen then strike on the sides of the tub for a considerable time, with mallets or wooden billets, to make the slime fall fast to the bottom. The lighter portions, consisting almost entirely of refuse matter, fall only after the knocking has ceased : the water is now run away ; then the very poor slime upon the top of the deposite is skimmed off, while the pure ore found at the bottom of the tub is lifted out, and laid on the bingstead. In this way the blende, which always accompa- nies galena in a greater or smaller quantity, is well separated. Smelling of lead ores. — The lead ores of Derbyshire and the north of England were anciently smelted in very rude furnaces, or boles, urged by the natural force of the wind, and were therefore placed on the summits or western slopes of the highest hills. More recently these furnaces were replaced by blast hearths, resembling smiths' forges, bat larger, and were blown by strong bellows, moved by men or water-wheels. The principal operation of smelting is at present always executed in Derbyshire in rerer- beratory furnaces, and at .Alston Moor in furnaces similar to those known in France by the name of Scotch furnaces. Before entering into the detail of the founding processes, we shall give a description of the furnaces essential for both the smelting and accessory operations. , . , . • t^ . t.- r 1. The reverberatory furnace called cupola, now exclusively used in Derbyshu-e loi the smelting of lead ores, was imported thither from Wales, about the year 1747, by a company of Quakers. The first establishment in this country was built at Kalstedgp. w the disti ict of Ashover. In the woiks where the construction of these furnaces is most improved, they are interiorly 8 feet long by 6 wide in the middle, and two feet high at the centre. The fire, placed at one of the extremities, is separated from the body of the furnace by a body of masonry, called the fire-bridge, which is two feet thick, leaving oniy from 14 to 18 inches between its upper surface and the vault. From this, the highest point, the vault gradually sinks towards the further end, where it stands only 6 inches above the sole. At this extremity of the furnace, there are two openings separated by a triangular prisra of fire-stone, which lead to a flue, a foot and a half wide, and 10 feet long, which is recurved towards the top, and runs into an upright chimney 55 feet high. The above flue is covered with stone slabs, carefully jointed with fire-clay, which may be removed when the deposite formed under them (which is apt to melt) requires to be cleaned out. One of the sides of the furnace is called the laborers' side. It has a door for throwing coal upon the fire-grate, besides three small apertures each about 6 inches square. These are closed with moveable plates of cast iron, which are taken off when the working requires a freer circulation of air, or for the stirring up of the materials upon the hearth. On the opposite side, called the working side, there are five apertures ; namely, three equal and opposite to those just described, shutting in like manner with cast iron plates, and beneath them two other openings, one of which is for running out the lead, and another for the scoriae. The ash pit is also on this side, covered with a little water, and so dis- posed as that the grate-bars may be easily cleared from the cinder slag. The hearth of the furnace is composed of the reverberatory furnace slags, lo which a 44 LEAD. proper shape has been given by beating them with a strong iron rake, before their entire solidification. On the laborers' side, this hearth rises nearly to the surface of the three openings, and falls towards the working side, so as to be 18 inches below the middle aperture. In this point, the lowest of the furnace, there is a tap-hole, through which the lead is run off into a large iron boiler (lea-pan), placed in a recess left out- side in the masonry. From that lowest point, the sole gradually rises in all directions, forming thus an inside basin, into which the lead runs down as it is smelted. At the usual level of the metal bath, there is on the working side, at the end furthest from the fire, an aperture for letting off the slag In the middle of the arched roof there is a small aperture, called the crovm-hole, which is covered up during the working with a thick cast iron plate. Above this aperture a large wooden or iron hopper stands, leading beneath into an iron cylinder, through which the contents of the hopper may fall into the furnace when a tiap or valve is opened. 2. The roasting furnace. — This was introduced about 30 years ago, in the neigh- borhood of Alston Moor, for roasting the ore intended to pass through the Scotch furnace, a process which greatly facilitates that operation. Since its first establishment it has suc- cessively received considerable improvements. J^lgs. 856, 857, 858, represent the cupola furnace at the Marquess of Westminster's lead smelting works, two miles from Holywell. Tlie hearth is hollowed out below the middle door of the furnace ; it slopes from the back and ends towards this basin. The distance from the lowest point of this concavity up to the sill of the door, is usually 24 inches, but it is sometimes a little less, according to the quality of the ores to be smelted. This furnace has no hole for running off the slag, above the level of the top hole for the lead t, like the smelting furnace of Lea, near Matlock. A single chimney stalk serves for all the establishments ; and receives all the fluos of the various roasting and reducing furnaces. Fig. 858 gives an idea of the distribution of these flues, a a a, , Theory of the above operation. — At Holj-well, Grassington, and m CurnwaiJ, the result of the first graduated roasting heat, is a mixture of undecomposed sulphuret of lead, with sulphate and oxyde of lead, in proportions which varj' with the degree of care bestowed upon the process. After the roasting, the heat is raised to convert the sludge into a pasty mass ; in which the oxyde and sulphate react upon the sulphuret, so as to produce a sub-sulphuret, which parts with the metal by liquation. The cooling of the furnace facilitates the liquation every time that the sub-sulphuret is formed, and the ore has passed by increase of temperature from the pasty into the liquid state. Cooling brings back the sludge to the pasty condition, and is therefore necessary for the due separation of the different bodies. The drying up of the thin slags by lime is intended tx) liberate the oxyde of lead, and allow it to react upon any sulphuret which may have resisted roasting or decomposition. It is also useful as a thicke^tcr, in a mechanical point of view. The iron of the tools, which wear away very fast, is also serviceable in re- dncin? the sulphuret of lead. The small coal added along with the iime at Grassington, and also sometimes at Holywell, aids in reducing the oxyde of lead, and in transforming the sulphate into sulphuret. 3. The smelting furnace or ore hearth.— This furnace, called by the French ecossaiSy is from 22 to 24 inches in height and 1 foot by 1| in area inside ; but its horizontal section, always rectangular, varies much in its dimensions at different levels, as shown in fig. 859. LEAD. 47 The hearth and the sides are of cast iron ; the sole-plate a b is also of cast iron, 2| inches thick, having on its back and two sides an upright ledge, a c, 2| inches thick and 4 J high. In front of the hearth there is another cast iron plate m n, called the uork atone, surrounded on every side excepting towards the sole of the furnace, by a leids de marc, while that produced by the reverberator)' furnace cannot be cupelled unless it gives 10 ounces per fodder ; and as in the English cupel- lation lead is constantly added anew without skimming, the litharge obtained in the second case can never be brought into the market, whereas the litharge of the leads from ihe Scotch furnace is of good quality. See the new method of enriching lead for cupel* lation, under Silver. As the smelting of galena, the principal ore of lead, is not a little complex, the follow- ing tabular view of the different processes may prove acceptable to the metallurgist i^ I. Class. Treated in re- verberatory furnaces. A Desulphura- tion by roast- ' ing. Treatment of ' 1. Pure ores. 2. Ores mixed with > saline gangues. > II. Class. Treated in the mill-slag- hearth, the fourneau H manche, or Scotch fur- nace. < B Desulphura- tion by iron. A Founding after roasting in a heap, or in a reverbera- tory. 3. Ores mixed with earthy gangues. 4. Ores mixed with several sulphu- rets. 5. Ores with earthy, ' saline, and sul- phurous gan- gues. 6. Ores with mattes, as at Vienne, in Dauphiny. Process of Pesey, Spain, &c. England, in gen- eral. Vicenago, in Italy, and Red- ruth, in Corii> wall. Combined with the above. \ B Founding with direct de- sulphuralion, by metallic iron. 7. Ores producing slags of various < silicates. 8. Ores producing | compound sili- \ cate sla?s. | I 9. Ores producing f slags composed { of silicates and^ subsilicates. Vienne, Poulla- ouen, and Tar- nowitz. Mattes, with raw lead. Workable lead, ^ without mattes. ^ Mattes and work- ) able lead. s Workable lead. Mattes and work- able lead. Poor mattes and workable lead. Many pla- ces. Villefoit. Several pla- ces. PontGibani and Scotch furnace. Baad-Ems Hartz, Tarnowitz. Tamciwitz. / 52 LEAD-SHOT. The annual production of lead in Europe may be estimated at about 80,000 tons ; of which four sevenths are produced in England, two sevenths in Spain, the remainder in Germany and Russia. France does not produce more than one five-hundredth part of the whole ; and only one fiAieth of its consumption. See Litharge, Minium, or Red Lead, Solder, Sugar or Acetate of Lead, Type Metal, and White Lead. LEAD-SHOT (Plomb de chasse, Fr. ; Schrot, Flintenschrotj Germ.). The origin of most of the imperfections in the manufacture of lead-shot is the too rapid cooling of the spherules by their being dropped too hot into the water, whereby their surfaces form a solid crust, while their interior remains fluid, and, in its subsequent concretion, shrinks, 80 as to produce the irregularities of the shot. The patent shot towers originally constructed in England obviate this evil by exposing the fused spherules after they pass through the cullender, to a large body of air during their descent into the water tub placed on the ground. The greatest erection of this kind is probably at Villach, in Carinthia, being 210 Vienna, or 249 English feet high. The quantity of arsenic added to the mass of melted lead, varies according to the quality of this metal ; the harder and less ductile the lead is, the more arsenic must be added. About 3 pounds of either white arsenic or orpiment is enough for one thousand parts of soil lead, and about 8 for the coarser kinds. The latter are employed preferably for shot, as they are cheaper and answer sufficiently well. The arsenical alloy is made either by introducing some of this substance at each melting, or by making a quantity of the compound considerably stronger at once, and adding a certain portion of this to each charge of lead. If the particles of the shot appear lens shaped, it is a proof that the proportion of arsenic has been too great ; but if they are flattened upon one side, if they are hollowed in their middle, called cupping by the workman, or drag with a tail behind them, the proportion of arsenic is too small. The following is the process prescribed by the patentees, Ackerman and Martin. Melt a ton of soft lead, and sprinkle round its sides, in the iron pot, about two shovelfuls of wood ashes, taking care to leave the centre clear ; then put into the middle about 40 pounds of arsenic to form a rich alloy with the lead. Cover the pot with an iron lid, and lute the joints quickly with loam or mortar, to confine the arsenical vapors, keeping up a moderate fire to maintain the mixture fluid for three or four hours ; aAer which skim carefully, and run the alloy into moulds to form ingots or pigs. The composition thus made is to be put in the proportion of one pig or ingot into 1000 pounds of melted ordi- nary lead. When the whole is well combined, lake a perforated skimmer and let a few drops of it fall from some height into a tub of water. If they do not appear globular, some more arsenical alloy must be added. Lead which contains a gowl deal of pewter or tin must be rejected, because it tends to produce elongated drops or tails. From two to three ions are usually melted at once in the large establishments. The surface of the lead gets covered with a crust of oxyde of a white spongy nature, some- times called cream by the workmen, which is of use to coat over the bottom of the cul- lender, because without such a bed the heavy melted lead would run too rapidly through the holes for the granulating process, and would form oblong spheroids. The mounting of this filter, or lining of the cullender, is reckoned to be a nice operation by the work- men, and is regarded usually as a valuable secret. The cullenders are hollow hemispheres of sheet iron, about 10 inches in diameter, per- ibrated with holes, which should be perfectly round and free from burs. These must be of a uniform size in each cullender ; but of course a series of different cullenders, with sorted holes for every different size of lead shot, must be prepared. The holei? have nearly the following diameters for the annexed numbers of shot. No. 0. 1. 2. 3. 4. JL of an inch. , 1 80 From No. 5 to No. 9 the diameter decreases by regular gradations, the latter being only ,1-. of an inch. • 60 The operation is always carried on with three cullenders at a time ; which are sup- ported upon projecting grates of a kind of chafing dish made of sheet iron somewhat like a triangle. This chafing dish should be placed immediately above the fall ; while at its bottom there must be a tub half filled with water for receiving the granulated lead. The cullenders are not in contact, but must be parted by burning charcoal, in order to keep the lead constantly at the proper temperature, and to prevent its solidifying in the filter. The temperature of the lead bath should vary with the size of the shot ; for the largest, it LEAD. 58 should be such that a bit of straw plunged into it will be scarcely browned, but for all it should be nicely regulated. The height from which the particles should be let fall varies likewise with the size of the shot ; as the congelation is the more rapid, the smaller they are. With a fall of 33 yards or 100 feet, from No. 4 to No. 9 may be made j but for larger sizes, 150 feet of height will be required. Every thing being arranged as above described, the workman puts the filter-stuff into the cullender, pressing it well against the sides. He next pours lead into it with an iron ladle, but not in too great quantity at a time, lest it should run through too fast. The shot thereby formed and found in the tub are not all equal. The centre of the cullender being less hot affords larger shot than the sides, which arc constantly surrounded with burning charcoal. Occasionally, also, the three cullenders employed together may have holes of different sizes, in which case the tub may contain shot of very various magnitudes. These arc separated from each other by square sieves of different fineness, 10 inches broad and 16 inches long, their bottoms being of sheet iron, pierced with holes of the same diameters as those of the cullenders. These sieves are suspended by means of two bands above boxes for receiving the shot ; one sieve being usually set above another in consecutive numbers, for instance, 1 and 2. The shot being put into the upper sieve, No. will remain in it. No. 1 will remain in the lower sieve, and No. 2 will, with all the others, pass through it into the chest below. It is obvious that by substituting sieves of successive fineness, shot of any dimension may be sorted. In the preceding process the shot has been sorted to size ; it must next be sorted to form, so as to separate all the spheroids which are not truly round, or are defective in any respect. For this purpose a board is made use of about 27 inches long and 16 broad, furnished partially with upright ledges ; upon this tray a handful or two of the shot to be sortefl being laid, it is inclined very slightly, and gently shaken in the horizontal direction, when the globular particles run down by one edge, into a chest set to receive them, while those of irregular forms remain on the sides of the tray, and are reserved to be remelled. Afler being sorted in this way, the shot requires still to be smoothed and polished bright. This* object is effected by putting it into a small octagonal cask, through a door in its side, turning ui)on a horizontal iron axis, which rests in plummer boxes at its ends, and is made to revolve by any mechanical power. A certain quantity of plumbago or black lead is put in along with the shot. Lead acted on by pure water so as to make it poisonoits. — ^Dr. H. Guenaude Mussy was summoned to Claremont in the beginning of October, 1848 ; and on his arrival was shown into the room of one of the members of the ex-royal family of France, who had been residing there since the preceding March. He found him lying down, with an anxious countenance, the conjunctiva of a yellowish color, and the flesh flabby, evidently proving a loss of substance. He told him he had been suffering for several days from violent colics, which had been relieved after a constipation of two days by abundant alvine evacuations, produced by a purgative draught. This was the third attack of the same nature during the space of five weeks. Some time before, towards the end of July, he had been suffering from colic, with nausea, frequent eructations and irregularity of the bowels. " I learnt that a brother of my patient had experienced the same symptoms ; but no one was astonished at it, as it was supposed he was suffering under a liver complaint contracted on the western coast of Africa. " A third patient, of forty-eight years of age, who was also subject to constipation, had violent colic a few days before, attended with nausea and even vomiting. " A few days elapsed, and no bad symptoms disturbed our security. My patients had resumed their usual occupations, and good appetites and pretty fair digestion, but were still very weak ; and pale sallow complexions had replaced the icteric color. " My delusions did not last long. About ten days after, a new access of symptoms began, with a painful sensation of constriction about the epigastric region, anxiety, nausea, and eructations." After describing the symptoms and the treatment resorted to before the real cause of the disorder was suspected, the doctor mentions the circumstances which led to the discovery, which induced him to administer sulphur in combination with iron internally, and to order sulphurous and soapy baths. He proceeds : — " The chemical action showed itself almost immediately by the black discoloration of the nails of the feet and hands, and by the appearance of similar spots on different parts of the skin. "One of the patients came out from the second bath with the abdomen entirely black. The soapy frictions and baths usually washed away the spots from the skin, put not those of the nails. The appearance of this reaction, which ii very common with men / u LEAD. LEATHER. 56 workin« in lead manufactories when using sulphurous baths, ia explained by the com- bination of sulphur with the saturnine molecules adhering to the skin. "In these cases it was evident that the lead was brought to the surface of the body by means either of subdaminal or follicular exhalations, and perhaps by both. "The metal is eliminated and transformed into sulphuret of lead by the sulphurous baths, and then taken off by the soapy frictions and baths. "These were not useless, for without them the lead deposited on the surface might have been carried again by absorption into the economy. "But the skin was not the only means of giving exit to the poison. I discovered U in the urine by a solution of hydros^lphate of ammonia. Some physicians and chemists look on sulphur as the only efficacious remedy; others, on the contrary, assert that it is without any effect. a r* * *u ^ "What I can tell you is, that the success was beyond my hopes. After two or three weeks I had the satisfaction of seeing my patients progressing rapidly and surely to wards recovery. This happy result induced me to try the same means with another person, older and of a weaker constitution, and consequently for whom I was most uneasy, and the result was as satisfactory. " One of my patients was accustomed to drink Vichy water at table. Ihis was a very unfortunate predisposing circumstance : it is probable that the salt of Vichy water, t e. bicarbonate of soda, united to the bed of Claremont water, had much to do with the violence of the attack under which he suffered. . , i • " At the time of my arrival at Claremont, there were thirty-eight inhabitants. "Tliirteen of these had been attacked, eleven men and two women. Four of them ■ had some symptoms two months previously to my arrival, the other cases occurred under my own eyes. Some even after the pipes had been cut oflF were aflfected, and on the continent a week after leaving England. "Six children in the household, aged from three to seven years, have been exempt from it. Only half of the patients have had the gums marked with the slate-colored line and spots of the same color on the raucous membrane of the mouth, and these spots and the bluish line of the gums, were observed on several others who did not experience or exhibit anything else, and those signs of the poison having been taken into the econ- omy have not yet disappeared. The morbid cause has acted in these cases, as it often does with caprice, and according to individual dispositions which defy every reason mg. "The malady has shown no respect for condition, and attacked indiscriminately ser- vants, aides-de-camps and princes. . r j "The spring that furnishes the palace of Claremont with water issues from a sand bed at about two miles distance. It was chosen for its uncommon purity from among . a great many others in its vicinity, and the water was thirty years ago conducted to the palace through leaden pipes. In the present day some other metal would perhaps have been selected, for experience has taught us that pure water, and especially dis- tilled water, acts rapidly on lead when it comes in contact with »K ^ , . ^, " Thus Tronchin proved that the inhabitants of Amsterdam were indebted to the ram water kept in leaden cisterns, for the colic they were so much subject to in his time. "The purity of the Claremont water becomes a most dangerous property, and not only to it but to other springs. Whilst I was combating its pernicious effects, 1 heard that there had been several similar cases in different parts of England ; thev are not uncommon in the county of Surrey, and especially in the neighborhood of Claremont Besides the cases published by Dr. Thompson, I know of several others at Weybndge, Windsor, and in different other places. . , , x-x r " I should inform you that Professor Hoffman has ascertained the quantity of me- tallic lead contained in the water examined by him. He has found that it amounted to a grain per gallon, an enormous quantity when we consider that the poisoiied water was used in all culinary and table purposes; and, previously to the discovery of its deleterious character, even in the preparation of ptisans and lavements. Le\d Shot has been manufactured in the United States in low towers, provided with an ascending stream of air, drawn up by a fan worked by water power, whereby a like cooling effect is obtained as by letting the melted lead fall from a high tower. LEATHER, (Cuir, Fr. ; Leder, Germ.); is the skin of animals, so modified by chem- ical means as to have become unalterable by the external agents which tend to de- compose it in its natural state. The preparation in a rude manner of this valuable substance has been known from the most ancient times, but it was not till the end of the last, and the beginning of the present century, that it began to be manufactured upon right principles, in consequence of the researches of Macbride, Deyeux, beguin, and Davy. There are several varieties of leather; such as sole leather, boot, or upper leather, sharaoy leather, kid or glove leather, Ac. Skins may be converted into lea- ther either with or without their hairy coat. * j * We shall treat first of sole and upper leathers, being the most important, and most custlv and difficult to prepare in a proper manner. These kinds consist of organized fibrous gelath^e or skin, cabined with the proximate vegetable principle tannin, and nrobablvalso some vegetable extractive. Under the articles Galls and Tannin will r?ound an account of Uie properties of this substance and the means of obtaining it in a stae of purity. Calf leather quickly tanned by an infusion of galls, consists of 61 par^s f/skin and 39 of vegetable matter in 100 by weight; by solution of catechu it consists f 80 of skin and 20 of vegetable matter ; by infusion of Leicester wiUow of iA-o skin, nd 25 5 veg^table^^^^^^^^^ by infusion of oak bark, of 73-2 skin and 26-8 vegetable matter By the slow process of tannmg, continued for three months, the increase of we ght' upon the skin in its conversion into leather, is greatly less; the vegetable consti- Sts being from Leicester wiUow only 13 per cent, of the leather, and from oak bark 15 T>er cent. Sole leather, however, generaUy contains no less than 40 per cent, of vege- rnhle matter In every astringent bark, the inner white part next to the alburnum, con- ^ins the largest quantity of tannin, and the middle colored part contains most extractive matter The outer surface or epidermis seldom furnishes either tannin or extractive matter' Youn<' trees abound most in the white cortical layers, and are hence more pro- ductive of tannin under equal weights, than the barks of old trees. In no case is there anv reason to beUeve that the gallic acid of astringent vegetables is absorbed in l>e pro- cess of making leather; hence Seguin's theory of the agency of that substance in disoxy- eenatin- skin, falls to the ground. The different qualities of leather made with the same kind of skin, seem to depend very much upon the diflerent quantities of extractive matter it may have absorbed. The leather made with infusion of galls, is generaUy harder and more liable to crack than the leather obtained from infusions of barks ; and It always contains a much larger proportion of tannin, and a smaller proportion of extrac- ^^When calf skin is slowly tanned in weak solutions of the bark, or of catechu, it com- bines with a good deal of extractive matter, and though the increase of the weight of the skin be comparatively small, yet it has become perfectly insoluble in water, forming a sofl, but at the same time a strong leather. The saturated infusions of astringent barks contain much less extractive matter in proportion to their tannin, than the weak infu- sions; and when skin is quickly tanned in the former, it produces a worse and less durable leather than when slowly tanned in the latter. In quick tanning, a considerable quantity of vegetable extractive matter is thus lost to the manufacturer, which might have been made to enter as a useful constituent into the leather. These observations show that there is sufficient foundation for the opinion of the common workmen, con- cerning what is technicaUy called feeding of leather, in the slow method of tanning; and though the processes of this art have been unnecessarily protracted by defective methods of steeping, and want of progressive infiltration of the astringent liquor through the skins, vet in general they appear to have arrived, in consequence of old experience, at a degree of perfection in the quaUty of the leather, which cannot be far exceeded by means of any theoretical suggestions which have been advanced. - . , On the first view it may appear surprising, that in those cases of quick tanning, where extractive matter forms a certain portion of the leather, the increase of weight is less than when the skin is combined with the pure tannin; but the fact is easily account- cd for, when we consider that the attraction of skin for tannin must be probably weak- ened by its union with extractive matter ; and whether we suppose that the tannin and extractive matter enter together into combination with the matter of skin, or unite with separate portions of it, still, in either case, the primary attraction of skm for tan must be to a certain extent diminished. In examining astringent vegetables in relation to their power of making leather, it is necessary to take into account not only the quantity they may contain of the substance precipitable by gelatine, but likewise the quantity and the nature of the extractive matter ; and in cases of comparison, it is essential to employ infusions of the same degree of con- centration. V 1- • ♦», Of all astringent substances hitherto examined, catechu is that which contains the laigest proportion of tanning and in supposing, according to the usual estimation, that fixim four to five pounds of common oak bark are required to produce one pound of leather, it appears, from the various synthetical experiments, that about half a Po«pd <>» catechu would answer the same purpose. Mr. Purkis found, by the results of different accurate experiments, that 1 pound of catechu was equivalent to 7 or 8 of oak bark. For the common purposes of the tanner, 1 pound of it would be equivalent also to 2^ pounds of ffalls, to 7| of the Leicester willow, to 11 of the bark of the Spanish chestnut, to 18 of the bark of the common elm, to 21 of the bark of the common willow, and to 3 pounds of sumach. Various menstrua have been proposed for the purpose of expediting and improving the process of tanning, among others, lime water, and solution of pearl-ash ; but as these two substances form compounds with tannin which are not decomposable by gelatine, it / M LEATHER. LEATHER. 67 I 'I H follows that their effects must be prejudicial. There is very little reason to suppose thai any bodies will be found which, at the same time that they increase the solubility of tan- nin in water, will not likewise diminish its attraction for skin. In this country all tanned leather is distinguished into two kinds, called hides and skins ; the former term being appropriated to that made from the larger animals, as bulls, buffaloes, oxen, and cows, into thick strong sole leather ; and the latter to that made from calves, seals, &c., into thinner and more flexible upper leather. Sometimes the hides are brought into the market merely dried, as from Buenos Ayres ; or dried and salted, as from Bahia and Pernambuco ; but the greater part are fresh from recently slaughtered animals. The heaviest ox-hides are preferred for forming butts or 6acfe«, which are manufactured as follows : — The washing process must be more or less elaborate, according to the state of the skins. Those that are salted and dry require to be steeped, beaten, and rubbed several times al- ternately, to bring them to the fresh condition. After removing the horns, the softened or recent hides are laid in a heap for two or three days, after which they are suspended on poles in a close room called a smoke- house, heated somewhat above the common temperature by a smouldering fire. In these circumstances, a slight putrefaction supervenes, which loosens the epidermis, and renders the hair easily detachable by the fleshing knife ; a large two handled implement, with a blunt edge, and bent to suit the curvature of the rounded beam of the wooden horse upon which the hide is scraped. See Currying. The next step is immersion in a pit containing water impregnated with about a 1000th part of sulphuric acid. This process is called raising, because it distends the pores, and makes the fibres swell, so as to render the skins more susceptible of the action of the tan- ning infusions. Forty-eight hours in general suffice for this operation, but more time may be safely taken. When the hides are found to be sufficiently raised, they are transferred to a pit, in which they are stratified with oak bark, ground by a proper mill into a coarse powder. The pit is then filled up with an infusion of oak bark called ooze, and the hides are allowed to remain in it for about a month or six weeks. By this time the tannin and extractive matter of the bark having combined intimately with the animal fibre, the pit is exhausted of its virtue, and must be renewed, by taking out the spent bark, and subjecting the skins to a fresh dose of oak bark and ooze. The hides which were placed near the top of the first pit, must be placed near the bottom of the next. In this mixture they remain, upon the old practice, about three months. The last process being repeated twice or thrice, perfectly tanned leather is the result. The hides are now removed from the pit, and hung up in a shed. In tha progress of drying, which should be slow, they are compressed with a steel tool, and beaten smooth, to render them more finn and dense. Some manufacturers place on the bottom of the pit 5 or 6 inches of spent bark, over it 2 inches of fresh bark, then a skin ; and so, alternately, a layer of new bark and a skin, till the pit is nearly full, reserving a small space at top for a thicker layer of bark, over which weighted boards are laid, to condense the whole down into the tanning infusion. The operation of tanning sole leather in the above way, lasts a year or a year and a half, according to the quality wanted, and the nature of the hides. A perfect leather is recognised by its section, which should have a glistening marbled appearance, without any white streaks in the middle. Crop hides are manufactured by immersion, during three or four days, in pits contain- ing milk of lime ; in which they are occasionally moved up and down in order to expose them equally to the action of this menstruum. They are then removed, and cleared from hair and impurities, by usmg the fleshing knife upon the horse ; after which they must be completely freed from the lime by a thorough washing. They are next plunged in pits containing a weak ooze or infusion of oak bark, from which they arc successively transferred into other pits with stronger ooze ; all the while being daily handled, that is, moved up and down in the infusion. This practice is continued for about a month or six weeks. They are now ready to be subjected to a mixture of ground oak bark and stronger ooze in other pits, to a series of which they are progressively sub- jected during two or three months. The hides are next put into large vats, called layers, in which they are smoothly strati- fied with more oak bark, and a stronger infusion of it. After six weeks they are taken out of these vats, and subjected to a new charge of the same materials for two months. This simple process is repeated twice or thrice, at the option of the manufacturer, till the hides are thoroughly tanned. They are then slowly dried, and condensed in the man- ner above described. These crop hides form the principal part of the sole leather used for home consumption in England. The process of tanning skins (as of calves, seals, &c.) is in some respects peculiar. They are left in the lime pits for about twelve days, when they are stripped of their hair washed in water, then immersed in a lixivium of pigeons* dung, called a grainer, of an a\kaline nature. Here they remain from eight to ten days, according to the state of the atmosphere, during which time they are frequently handled, and scraped on both sides upon a convex wooden beam. This scraping or xoorking, as it is termed, joined to the action of the grainer, serves to separate the lime, oil, and glutinous matter, and to render the skin pliant, soft, and ready to imbibe the tanning principle. They are with this view transferred into pits containing a weak solution of bark, in which they undei^o nearly the same treatment as described above for crop hides ; but they are not com- monly stratified in the layers. The time occupied in tanning them is usually limited to three months. They are then dried, and disposed of to the currier, who dresses and blackens them for the upper leathers of boots and shoes, for harness, and other purposes. The light and thin sorts of cow and horse hides are often treated like calf skins. In all the above processes, as the animal fibres on the surface of the skin absorb most readily the tanning principles, and thereby obstruct, in a certain degree, their passage into the interior fibres, especially of thick hides, it becomes an object of importance to contrive some method of overcoming that obstacle, and promoting the penetration of the tan. The first manufacturer who appears to have employed efficacious mechaniad means of favoring the chemical action was Francis G. Spilsburj', who in April, 1823, obtained a patent for the following operation: — After the hides are freed from the hairs, &c. in the usual way, they are minutely inspected as to their soundness, and if any holes be found, they are carefully sewed up, so as to be water tight. Three frames of wood are provided of equal dimensions, fitted to each other, with the edges of the frames held together by screw bolts. A skin about to be tanned is now laid upon the frame, and stretched over its edges, then the second frame is to be placed upon it, so that the edges of the two frames may pinch the skin all round and hold it securely ; another such skin is then stretched over the upper surface of the second frame, in like manner, and a third frame being set upon this, confines the second skin. The three frames are then pinched tightly together by a series of screw bolts, passing through ears set round their outer edges, which fix the skin in a proper manner for being operated upon by the tanning liquor. A space has been thus formed between the two skins, into which, when the frames are set upright, the infusion is introduced by means of a pipe from the cistern above, while the air is permitted to escape by a stopcock below. This cock must of course be shut whenever the bag is filled, but the one above is left open to maintain a communica- tion with the liquor cistern, and to allow the hydrostatic pressure to force the liquoi throush the cutaneous pores by a slow infiltration, and thus to bring the tannin into con- tact with all the fibres indiscriminately. The action of this pressure is evinced by a con- stant perspiration on the outer surfaces of the skins. When the tanning is completed, the upper stopcock is closed, and the under is opened to run off the liquor. The frames are now removed, the bolts are unscrewed, and the pinched edges of the skins pared off; after which they are to be dried and finished in the usual manner. A modification of this ingenious and effectual process was made the subject of a patent, by William Drake, of Bedminster, tanner, in October, 1831. The hides, after the usual preparatory processes, are immersed in a weak tan liquor, and by frequent handling or turning over, receive an incipient tanning before being submitted to the infiltration plan. Two hides, as nearly of the same size and shape as possible, are placed grain to grain, when their corresponding edges are sewed firmly together all round by shoemakers* waxed thread, so as to form a bag sufficiently tight to hold tan liquor. This bag must then be suspended by means of loops sewed to its shoulder end, upon pegs, in such a manner that it may hang within a wooden-barred rack, and be confined laterally into a book form. About an inch of the bag is left unsewed at the upper end, for the purpose of introducing a funnel through which the cold tan liquor is pourel into the bag till it be full. After a certain interval which varies with the quality of the hides, the outer surface becomes moist, and drops begin to form at the bottom of the bag. These arc received in a proper vessel, and when they accumulate sufficiently may be 7>oured back into the funnel ; the bag being thus, as well as by a fresh supply from above, kept constantly distended. When the hides are observed to feel hard and firm, while every part of them feels equally damp, the air of the tanning apartment having been always well ventilated, is now to be heated by proper means to a temperature gradually inereasing from 70** to 150° of Fahrenheit's scale. This heat is to be maintained till the hides become fiiiner and harder in all parts. When they begin to assume a black appearance in some parts, and when the tan liquor undergoes little diminution, the hides may be considered to be tanned, aud the bag may b^ emptied by cutting a few stitches at its bottom. iTie outer e-iges being pared off, the hides are lo be finished in the usual way. During 58 LEATHER. Uquor! ^°™tion of furrows by the bars, and to facUilale the equable action of the aJI ^^-^ P""*;? f '^^ patentee says, that a hide may be tanned as completely in ten days as it could be in ten months by the usual method. I have seen a piece of so e leather thus rapidly tanned, and it seemed to be perfect. How it may wear, clparerwi ^th^ made in the old way, I cannot pretend to determine. ' comparea with that Messrs. Knowlys and Duesbury obtained a patent in Au^st, 1826, for accelerating the impiegnation of skins with tannin, by suspending them in a close vessel, fmm which the air is to be extracted by an air pump, and then the tanning infusion is to be admU.S^ Ihortlimf' '" '"PP«^^^ t« penetrate the hide so effectually as to tan it uniformly in a About 32 years ago, a similar vacuum scheme was employed to impre«Tiate with ^rR^^sJ'TkZClt'' '^" ''^' '^ '"""'' ''""' ^"' '^' ^""^^ loomsof Messrs. Raddiff Danish leather is made by tanning lamb and kid skins with willow bark, whence it de^ nves an agreeable smell. It is chiefly worked up into gloves. 0/ihe tawing or dressing of skins for gloves, and white sheep leather. lirn^^^'^fT'^^'^^J^'fl' ""'^ *'! = 1. washing the skins; 2. properly treating them with lime ; 3. taking off the fleece ; 4. treatment in the leather steep. Ashed erected upon the side of a stream, with a cistern of water for washing the skins; wooden horses for ceaning them with the back of the fleshing knife; pincers for removmg the fibres of damaged wool; a plunger for depressing the skin's Tnth" pits ; a hme pit ; a pole with a bag tied to the end of it ; a two-handed fleshing knife • ntln^ir^ r; •"" ^^ /"Ir V""^"' ^Si- thickened in the middle; such are somi of the nU^nt V- ""? fstabhshment. There must be provided also a table for applying the oil to the skins; a fulling mill, worked by a water-wheel or other power; a dressin- pe- • a press for squeezing out the fatty filth ; a stove ; planks mounted upon legs, for sfretchl Fresh skins must be worked immediately after being washed, and then dried other- wise they ferment, and contract either indelible spots, or get tender in certain points ^o as to open up and tear under the tools. When received in the dry state they should be steeped in water for two days, and then treated as fresh skins. They are next stron^^lv rubbed on the convex horse-beam with a round-edged knife, in order to make them nli- ant. The rough parts are removed by the fleshing knife. One workman can in this way prepare 200 skins in a day. «« wajr The flesh side of each being rubbed with a cold cream of lime, the skins are piled together with the woolly side of each pair outermost, and the flesh sides in contact. They are left m this state for a few days, tiU it is found that the wool may be easUy re- moved by ;j/ttcfciwg. ' asuj' IC They are next \yashed in running water, to separate the greater part of the lime stripped of the wool by small spring tweezers, and then fleeced smooth by means of the rollmg-pm, or sometimes by rubbing with a whetstone. Unless they be fleeced soon after the treatment with lime, they do uot well admit of Uiis operation subsequently, as they are apt to get hard. h j> «w They are now steeped in the milk of lime-pit, in order to swell, soften, and cleanse them; afterwards ma weak pit of ol.l lime-water, from which they are taken out and clramed. fnis steeping and draining upon inclined tables, are repeated frequently durin^ the space of 3 weeks. Only the skins of young animals, or those of inferior value are tawed. Sometimes the wool is left on, as for housings, &c. The skins, after having been well softened in the steeps, are rubbed on the outside with a whetstone set m a wooden case with two handles, in order to smooth them completely by removing any remaining filaments of wool. Lamb skins are rubbed with the pin in the direction of their breadth, to give them suppleness ; but sheep skina are fuUed with water a.one. They are now ready for the brannivg, which is done bv mixing 40 lbs. of bran with 20 gallons of water, and keeping them in this fermentable mature for throe weeks— with the addition, if possible, of some old bran water Hero they must te frequently turned over, and carefully watched, as it is a delicate op'eration In the course of two days in summer, and eight in winter, the skins are said to be* raised, when they sink in the water. On coming out of the bran, they are ready for the whii'.e stufi ; which is a bath composed of alum and sea-salt. Twelve fourteenl and sometmies eighteen pounds of aJnm for 100 skins, form the basis of the bath • to which two and a half pounds of salt are added in winter, and three in summer These ingredients are introduced into a copper with twelve gallons ol water The salt aids m the whitening action. When the solution is about to boil, three gallons of it are LEATHER. 69 passed through the cullender into a basin ; in this 26 skins are worked one after another, and, after draining, they are put together into the bath, and left in it for ten minutes to imbibe the salts. They are now ready to receive the paste. For 100 skins, from 13 to 15 pounds of wheat flour are used along with the yolks of 50 eggs. After having warmed the alum bath through which the skins have been passed, the flower is dusted into it, with careful stirring. The paste is well kneaded by the gradual addition of the solution, and passed through the cullender, whereby it becomes as cleur as honey. To this the yolks being added, the whole is incorporated with much manual labor. The skins are worked one after another in this paste ; and afterwards the whole together are left im- mersed in it for a day. They are now stretched and dried upon poles, in a proper apart- ment, during from 8 to 15 days, according to the season. The effects of the paste are to whiten the skins, to soften them, and to protect them from the hardening influence of the atmosphere, which would naturally render them brittle. They would not bear working upon the softening iron, but for the emulsion which has been introduced into their substance. With this view they are dipped in a tub of clear water during five or six minutes, and then spread and worked upon the board. They are increased by this means in length, in the proportion of 5 to 3. No hard points must be left in them. The whiteness is also better brought out by this operation, which is performed upon the flesh side. The softening tool is an iron plate, about one foot broad, rounded over above, mounted upon an upright beam, 30 inches high, which is fixed to the end of a strong horizontal plank, 3^ feet long, and 1 broad. This plank is heavily loaded, to make it immoveable upon the floor. Sometimes the skins arc next spread over an undressed clean skin upon the horse, and worked well with the two-handled knife, for the purpose of removing the first and second epidermis, called the feur and arriere-Jleur by the French megissiers. They are then dried while stretched by hooks and strings. When dry they are worked on the stretching iron, or they are occasionally pol- ished with pumice stone. A delicate yellow lint is given by a composition made of two parts of whitening, and one of ochre, applied in a moistened state, and well worked in upon the grain side. After being polished with pumice, they are smoothed with a hot iron, as the laundresses do linen, whereby they acquire a degree of lustre, and are ready to be delivered to the glover. For housings, the best sheepskins are selected, and such as are covered with the lonsrest and most beautiful fleece. They are steeped in water, in order to be cleansed and soft- ened ; after which they are thinned in?ide by the fleshing knife. They are now steeped in an old bran pit for 3 or 4 days, when they are taken out and washed. They arc next subjected to the white or alum bath, the wool being carefully folded within ; about 18 pounds of alum being used for 100 skins. The paste is made as for the fleeced skins, but it IS merely spread upon their flesh side, and left upon them for 18 hours, so as to stiffen. They are then hung up to dry. They are next moistened by sprinkling cold water upon them, folded up, piled in a heap, and covered with boards weighted with heavy Stones ; in which state they remain for two days. They are next opened with a round iron upon the horse, and subjected to the stretching iron, being worked broadwise. They are dried with the fleece outermost, in the sun if possible ; and are finished upon the stretcher. Calf and lamb skins with their hair and wool are worked nearly in the same manner ; only the thicker the skin, the stronger the alum bath ought to be. One pound of alum and one of salt are required for a single calf skin. It is left four days in this bath, after which it is worked upon the stretcher, then fulled ; when half dry the skins are opened r.pon the horse. In eight days of ordinary weather, they may be completely dressed. Lamb skins are sometimes steeped during eight days in a bath prepared with unbolted rye flour and cold water, in which they are daily moved about two or three times. They are then dried, sti stched upon the iron, and switched upon the fleecy side. Chamois cr Shamoy leather.— The skins are first washed, limed, fleeced, and branned as above described. They are next efflowered, that is, deprived of their epidermis by a concave knife, blunt in its middle part, upon the convex horse-beam. The cutting part sirves to remove all excrescences, and to equalize the thickness, while the blunt part softens and smooths. The skins of goats, does, and chamois, are always treated in this way. 1 hey are next subjected to the fermenting bran steep for one or two davs, in ordiivary weather ; but in hot weather for a much shorter time, sometimes only moving them m the sour bran liquor for a few minutes. Thev are lastly wrung at the peg, and subjected to the lulling mill. ' When the skins have been sufficiently swelled and suppled by the branning, they may receive the hrst oil as follows : a dozen skins being stretched upon the table; the fingers are dipped m the oil and shaken over the skins in different places, so as to imi>art enough of It to imbue the whole surface slightly, by friction with the palms of the nands. It is to the outside or grain that the oil is applied. The skins are folded four together, so as to form balls of the size of a hog's bladder, and thrown into the .trough 11 60 LEATHER. P |i! ■I ! of the fulling miU, to the number of tvelve dozen at once. Here they remain exposed to the heater for two, three, or four hours, according to their nature and the state of the weather. They are taken out, aired, oiled, and again fulled. The airing and fulling are repeated several times, with more or less frequent oilings. Any cheap animal oil is employed. After these operations, the skins require to be subjected to a fermenting process, to dilate their pores and to facilitate iheir combination with the oil. This is perfoimed in a cham- ber only 6 feet high, and 10 or 12 feet square. Poles are suspended horizontally a few inches from the ceiling, with hooks fixed in them to which the skins are attached A somewhat elevated temperature is maintained, and by a stove if need be. This onera- tion requires great skill and experience. The remainder of the epidermis is next removed by a blunt concave knife and the horse ; whereby the surface is not cut, but rather forcibly scraped. The skins are now scoured to carry off the redundant oil ; which is effected by a pot- ash ley, at two degrees Baume, heated no hotter than the hand can bear. In this they are stirred briskly, steeped for an hour, and lastly wrung at the peg. The soapy liquor thus expelled is used for inferior purposes. The clean skins, after being dried, are finished nrst on the stretcher-iron, and then on the herse or stretching frame. Leather of Huvgary.— This is manufactured by impregnating strong hides with alum common salt, and suet ; by a rapid process which is usually completed in the space of two months. The workshop is divided into two parts : 1. A shed on the side of a stream, furnished with wooden horses, fleshing knives, and other small tools. In one corner is a furnace with a boiler for dissolving the alum, a vat for immersing the hides in the solution, and several subsidiary tubs. 2. A chamber, 6 feet high, by 15 feet square, capable of being made very tight, for preser%in? the heat. In one corner is a copper boiler, of sufficient size to contain 170 pounds of tallow. In the middle of the stoyeisasquarestoneslab, upon which an iron grate is placed about a vard square This is covered with charcoal. At each side of the stove are large tables, which occupy its wliole length, and on which the leather is spread to receive the g'-ease. The upper part below the ceiling is filled with poles for hanging the leather upon to be heated ihc door is made to shut perfectly close. The first operations are analogous to those of tanning and tawing ; the skins beine washed, cut m halves, shaved, and steeped for 24 hours in the river. They are then cleaned with 5 or 6 pounds of alum, and 3^ pounds of salt, for a piece of hide which weighs from 70 to 80 pounds. The common salt softens the effect of the alum attracts the moisture of the air, and preserves the suppleness of the skin. When the alum and salt are dissolved, hot water is poured upon the hides placed in a vat, and they are tramped upon by a workman walking repeatedly from one end of the vat to the other. They are tlhen transferred into a similar vat containing some hot water, and similarly tramped upon lliey are next steeped for eight days in alum water. The same round of operations is repeated a second time. The skins are now dried either in the air, or a stove room ; but before being quite dry they are doubled together, well stretched to take out the wrinkles, and piled up. When dry, they are again tramped to open the pores as well as to render the skin pliant, after which they are whitened by exposure to the sun. Tallow of inferior quality is employed for greasing the leather. With this view the hides are hung upon the poles in the close stove room, then laid upon the table and be- smeared with the tallow melted tUl it begins to crackle. This piece is laid on another table, is there covered with a second, similariy greased, and so forth. Three pounds of fat are commonly employed for one piece of leather. When the thirty strips, or fifteen hides passed through the grease in one operation are completed, two workmen take the first piece in their hands, and stretch it over the burning charcoal on the grate for a minute, with the flesh side to the fire. The rest are passed over the flame in like manner. After flaming, the pieces are successively laid on an inclined table exposed to the fire, where thev are covered with a cloth. They are finally hung upon poles in the air to dry ; and if the weather be warm, they are suspended only during the night, so as to favor the hardening of the grease. Instead of the alum bath, M. Curaudau has employed with advantage a steep of dilute sulphuric &C1Q* Rusxia leather. — The Russians have long been possessed of a method of making a peculiar leather called by them jucten, dyed red with the aromatic saunders wood. This article has been much sought after, on account of not being subject to mould in damp situations, being proof against insects, and even repelling them from the vicinity of Its odor. The skins are freed from the hair or fleece, by steeping in an ash-lye too weak to act upon the animal fibres. They are then rinsed, fulled for a longer or shorter time according to their nature, and fermented in a proper steep, after having been washed m hot water. They are taken out at the end of a week, but they may be steeped LEATHER. 61 a second time if deemed necessary, to open their pores. They are now cleaned by working them at the horse on both the flesh and grain sides A paste is next composed, for 200 skins, of 38 pounds of rye flour, which is set to ferment with leaven. This dough is worked up with a sufficient quantity of water to form a bath for the skins, in which they are soaked for 48 hours ; they aie then trans- ferred into small tubs, where they remain during fifteen days, after which they are washed at the river. These operations serve to prepare the skins for absorbing the astringent juices with uniformity. A decoction of willow bark {salix cinerea and salix caprea) be- mg made, the skins are immersed in the boiler whenever the temperature of the Uquor is sufficiently lowered not to injure the animal fibres, and handled and pressed for half an hour. This manipulation is repeated twice daily during the period of a week. The tanning infusion is then renewed, and applied to the same skins for another week ; after which, being exposed to the air to dry, they are ready for being dyed, and then curried with the empyreumatic oil of the bark of the birch tree. To this substance the Russia leather owes its peculiarities. Many modes have been prescribed for preparing it ; but the following is the one practised in Russia. The whitish membranous epidermis of the birch, stripped of all woody parts, is intro- duced into an iron boUer, whicii, when stuffed full, is covered tight with a vaulted iron lid, having a pipe rising from its centre. A second boUer into which this pipe passes without reaching its bottom, is set over the first, and is luted lo it at the edges, after the two are bolted together. They are then inverted, so that the upper one contains the birch bark. The under half of this apparatus is sunk in the earth, the surface of the upper boiler is coated over with a clay lute, then surrounded with a fire of wood, and exposed to a red heat, till the distillation be completed. This operation, though rude in appearance, and wasteful of wood, answers its purpose perfectly well. The iron cylinder apparatus used in Britain for distilling wood vinegar, would, however, be much more convenient and pro- ductive. When the above boilers are unluted, there is found in the upper one a very light powder of charcoal, and in the under one which served as a receiver, there is an oily, brown, empyreumatic fluid, of a very strong smell, which is mixed with the tar, and which floats over a small quantity of crude vinegar. The former matter is the oU employed to impregnate the skins, by working it into the flesh side with the currier's tools. It is diffi- cult to make this oil penetrate with uniformity ; and the Russians do not always succeed m this process, for they turn out many skins in a spotted state. This oil is at present obtained in France by distilling the birch bark in coppei stills, and condensing the pro- ducts by means of a pipe plunged in cold water. About 60 per cent, of the weight of the bark is extracted. The skins unbibe this oil most equally before they are fully dry. Care must be taken not to apply too much of it, for fear of its passing through and staining the grain side of the leather. Chevreul has investigated the chemical nature of this odoriferous substance, and finding it to be a peculiar compound, has called it betuline. In the Franklin Institute for February, 1843, Mr. Gideon Lee has published some ju- dicious observations on the process of tanning. He believes that much of the original gelatine of the hides is never combined with the tannin, but is wasted ; for he thinks that 100 lbs. of perfectly dry hide, when cleaned from extraneous matter, should, on chemical principles, afford at least 180 lbs. of leather. The usual preparation of the hide for tanning he believes to be a wasteful process. In the liming and bating, or the unhairing and the cleansing, the general plan is first to steep the hides in milk of lime for one, two, or three weeks, according to the weather and texture of the skin, until the hair and epidermis be so loosened as to be readily removed by rubbing down, by means of a knife, upon a beam or block. Another mode is to suspend the hides in a close chamber, heated slightly by a smouldering fire, till the epidermis gets loosened by incipient putrefaction. A third process, called sweating, used in Germany, consists in laying the hides in a pack or pile, covered with tan, to promote fermentative heat, and to loosen the epidermis and hairs. These plans, especially the two latter, are apt to injure the quality of the hides. The bate, consists in steeping the haired hides in a solution of pigeon's dung, con- taining, Mr. Lee saj^s, muriate of ammonia, muriate of soda, Ac. ; but most probably phosphates of ammonia and lime, with urate of ammonia, and very fermentable animal matter. The dry hides are often subjected first of all to the operation of the fulling- stocks, which opens the pores, but at the same time prepares them for the action of the liming and bate ; as also for the introduction of the tanning matter. When the full- ing is too violent, the leather is apt to be too limber and thin. Mr. Lee conceives that the liming is injurious, by carrying off more or less of the gelatine and albumen of the skin. High-limed leather is'loose, weighs light, and wears out quickly. The subsequent fermentation in the bating aggravates that evil. Another process has there- fore been adopted in New York, Maine, New Hampshire, and some parts of Philadel- phia, called, but incorrectly, cool sweating, which consists in suspending the hides in a 62 LEATHER. ( i subterranean vault, in a temperature of 50° Fahr., kept perfectly damp, by the tricks ling of cold spring water from points in the roof. The hides being first soaked, are sus- pended in this vault from 6 to 12 days, when the hair is well loosened, by the mere softening effect of moisture, without fermentation. LEATHER, MOROCCO. {Maroquin, Fr. ; Saffian, Germ.) Morocco leather of the finer quality is made from goatskins tanned with sumach ; inferior morocco leather from sheepskins. The goatskins as imported are covered with hair ; to remove which they are soaked in water for a certain time, and they are then subjected to the operation called breaking, which consists in scraping them clean and smooth on the flesh side, and they aje next steeped in lime-pits (milk of lime) for several days, during which period they are drawn oxU, with a hook, from time to time, laid on the side of the pit to drain, and replunged alternately, adding occasionally a little lime, whereby they are eventually deprived of their hair. When this has become sufficiently loose, the skins are taken out one by one, laid on convex beams, the work-benches, which stand in an inclined position, resting on a stool at their upper end, at a height convenient for tlfe workman's breast, who scrapes off the hair with a concave steel blade or knife, having a handle at each end. When unhaired, the skins are once more soaked in milk of lime for a few days, and then scraped on the flesh side to render it very even. For removing the lime which obstructs their pores, and would impede the tanning process, as well as to open these pores, the skins are steeped in a warm semi-putrid alkaline liquor, made with pigeons' and hens' dung diffused in water. Probably some very weak acid, such as fer- mented bran-water, would answer as well, and not be so offensive to the workmen. (In Grermany the skins are first washed in a barrel by a revolving axle and discs.) They are again scraped, and then sewed into bags, the grain outermost, like bladders, leaving a small orifice, into which the neck of a funnel is inserted, and through which is poured a certain quantity of a strong infusion of the sumach ; and they are now rendered tight round the orifices, af\er being filled out with air, like a blown bladder. A parcel of these mflttled skins are thrown into a very large tub, containing a weaker infusion of sumach, where they are rolled about in the midst of the liquor, to cause the infusion within to act upon their whole surface, as well as to expose their outsides uniformly to the tan- ning action of the bath. After a while these bladder-skins are taken out of the bath, and piled over each other upon a wooden rack, whereby they undergo such pressure as to force the enclosed infusion to penetrate through their pores, and to bring the tannin of the sumach into intimate contact, and to form a chemical combination with the skin fibres. The tanning is completed by a repetition of the process, of introducing some infusion or decoction into thtfm, blowing them up, and floating them with agitation in the ^ath. In this way goatskins may be well tanned in the course of one dav. The bags are next undone by removmg the sewing, the tanned skins are scraped aa before on the currier's bench, and hung up in the drjing loft or shed ; they are said now to be " in the crust." They are again moistened and smoothed with a rubbing- tool before being subjected to the dyeing operations, in which two skins are applied face to face to confine the dye to one of their surfaces only, for the sake of economizing the dyeing materials which may be of several different colors. The dyed skins are grained by being strongly rubbed with a ball of box-wood, finely grooved on its surface. Preparatory to being dyed, each skin is sewed together edgewise, with the grain on the outside, and it is then mordanted either with a solution of tin, or with alum water. The color is given by cochineal, of which from 10 to 12 ounces are required for a dozen of skins. The cochineal being boiled in water along with a little tartar or alum for a few minutes, forms a red liquor, which is filtered tlirough a linen cloth, and put into a clean cask. The skins are immei*sed in this bath, and agitated in it for about half an hour; thev are taken out and beaten, and then subjected to a second immersion in the cochineal bath. After being thus dyed, they are rinsed and tanned with Sicilian su- mach, at the rate of two pounds for a skin of moderate size. This process is performed in a large tub made of white wood, in the liquor of which the skms are floated like so many bladders, and moved about by manual labor during four houra They are then taken out, drained, and again subjected to the tanning liquor; the whole pro- cess reqiiiring a space of twenty-four hours. The skins are now unstitched, rinsed, fulled with beetles, drained, rubbed hard with a copper blade, and lastly hung up to dry. Some manufacturers brighten the color by applying to the surface of the skins, in a damp state, a solution of carmine in ammonia with a sponge; others apply a decoction of saffron to enliven the scarlet tint. At Paiis the morocco leather is tanned by agita- tion with a decoction of sumach in large casks made to revolve upon a horizontal axis, like a barrel churn. White galls are sometimes substituted for sumach ; a pound being used for a skin. The skins must be finally cleaned with the utmost care. The black dye is given by applying with the brush a solution of red acetate of iron to the grain side. Blue is communicated bv the common cold indigo vat ; violets, with a LEATHER. U light blue followed by cochineal red ; green, by Saxon blue followed by a yellow dye, usually made with the chopped roots of the barberry. This plant servos also for yel- lows. To dye olive, the skins are first passed through a weak solution of green vitriol, and then through the decoction of barberry root, containing a little Saxon blue. Puce color is communicated by logwood with a little alum ; which may be modified by the addition of a little Brazil wood. In all these cases whenever these skins are dyed, they should be rinsed, wrung, or rather drained, stretched upon a table, then besmeared on the grain side with a film of linseed oil applied by means of a sponge in order to pro- mote their glossiness when curried, and to prevent them becoming horny by too rapid drying. The last process in preparing morocco leather is the currying, which brings out the lustre, and restores the original suppleness. This operation is practised in different manners, according to the purpose the skins are to serve. For pocket-books, portfolios, and case-making in general, they must be thinned as much as possible upon the flesh side, moistened slightly, then stretched upon the table, to smooth them ; dried again, moistened, and lastlj'^ passed two or three times through the cylinder press in different directions, t'> produce the crossing of the grain. The skins intended for the shoemaker, the saddler, the bookbinder, — ^ ^^ ^ p- 42. Groiv» of Crimea gray lamb 48. rimea gray lamb. Ukraine black lamb. / 98 LEATHER SPUmNG. w lit !! i^i 44. Group of Aatracan black lamK 46. U, 48. ML 60. M <( Astracan gray lamb. Persian black lamb. Persian gray lamb. Spanisli lamb. Hungarian lamb. Engbsh lamb. The gray and black Persian lamb is mostly used for gentlemen's cloak and coat lin- ings, for facings, collars, caps, Ac, and also lor army purposes. The Astracan lamb is a rich, wavy, glossy, black skin, very short in the fur, having the appearance of beau- tiful watered silk : in order to obtam this choice skin, it is averred that the parent sheep is destroyed a certain time before the birth of the lamb. The Persian gray and black lamb is covered with very minute curls; this is produced, it is said, by the ani- mal being as soon as bom sewn up tightly in a leathern skin, which prevents the curl expanding. The Hungarian lamb is produced in that country in immense numbers ; of It the national coat, called the Juhasz Bunda, is made. In the summer or wet wea- ther the fur or woolly part is worn outside ; in winter, when warmth is required, it is reversed: the skin is tanned or dressed in a way peculiar to the country, and decorirted and embroidered in accordance with the means and taste of the wearer. In Spain the lamb-skin is used for the well-known characteristic short jacket of that country, which is adorned with filigree silver buttons; the coarser kinds of both colors are used for our cavalry, and is also employed for mounting and bordering skins, as leopards, tigers, Ac, for ornamental and domestic purposes. In the reign of Richard II., the sergeant- at-law wore a robe furred inside with white lambskin and a cape of the same. 61. Group of Perewartzki. 62. " Hamster. The above are from Russia: the former is used by ladies ; the latter is made into cloak linings, which are exceedingly light, durable, and cheap. 63. Group of colored cat 64. " black cat 66. " black Dutch. 66. ** colored Dutch. Tlie cat, properly attended to and bred purposely for its skin, supplies a most use- ful and durable fur: in Holland it is bred and kept in a confined state till the fur is in its greatest perfection, and is fed entirely on fisli. In other countries and especially in our own, it is produced in large numbers. The wild cat is much larger ana longer in the fur, and is met with in extensive forests, particularly in Hungary : the color is gray, spotted with black, and its softness and durability render it suitable for cloak and coat linings, for which purposes it is much used. The black species is also much in request, and similarly use^ and with the spotted and striped varieties, is made into wrappers for open carriages, sleigh coverings, and railway travelling. 92. Group of dyed lynx, see No. 8. 94* " pengum {Speniscus aptenodytes). 96. " grebe {Podiceps cristata). The grebe is an aquatic bird, inhabiting most of the large lakes in Europe. TIjc choicest specimens are from Geneva, Italy, and Holland. The feathers are of rich white, havmg the appearance of polished silver, the plumage on the outer edge of the skin being a rich dark brown ; it is used by ladies and forms a beautiful article of dress, and is worn as trimmings for the trains of court and drawing-room dresses, for muflfs, cuffs, boas, Ac It is verv durable ; the exquisite smoothness of its fea- thers prevents its soiling with wear, 96. Specimen of swan feathers. 97. " goose feathers. 98. " eider down. The bird from which the down is taken is found* in large numbers in Iceland, Nor- way, Sweden, Ac. ; its color is dark gray, and its elasticity, lightness, and resistance to wet, are prominent amongst its other advantages: it is used for the inside stufiing of muffs. On the continent the well-known eider-down quilts are largely used. 99 — 116. Suits of Russia sable; Hudson's Bay sable; sable tail, mink ; chinchilla; grebe; sea otter; Siberian squirrel, with tails ; kolinski; minever; ermine; moleskin; natural beaver; dyed beaver; seal; swan; goose-down. The down of the goose is manufactured by being sewn on textile fabrics. It is a specimen of Irish industry, and has been patronized and sold in England extensively for the benefit of the Irish female poor, by whom it has been made up. The price, compared with the true swan's down, is very moderate. Being sewn upon cloth, it can oe washed. LEATHER SPLITTING. This operation is employed sometimes upon certain LEATHER SPLITTING. iorts of leather for glovers, for bookbinders, sheath-makers, and always to giv« a uni- form thickness to the leather destined for the cotton and wool card-makers. J*lg*. 863, 864, 866, 866, represent a well-contrived machine for that purpose, of which Jig. 863 shows the front view. Jig. 864 a view from the left side, Jig. 866 a ground plan, &nd Jig. 8C5 a vertical section across the machine, a is a strong table, furnished with four legs b, which to the right and left hand bears two horizontal pieces c. Each of 868 2 X «X oX these pieces is cut out in front, so as to form in its substance a half-round fork, that receives a cylinder d^ carrying on its end a toothed spur-wheel e. Motion is com- municated to the wheel by means of the handle/, upon whose axis the pinion, t, is fixed, working into the wheel d, made fast to the end of the cylinder round which the leathei 18 rolled. The leather is fixed at one of its ends or edges to the cylinder, either with » wedge pressed into a groove, or Ay a moveable segment of the cylinder itself. The table, a, is cut out lengthwise with a slot, that is widened below, as shown in fig. 865. The knife h (/lg». 865 and 866) is fixed flat upon the table with screw bolts, whose / 70 LEGUMINE, LIMESTONE. 71 I-. M m ill if I ii heads are countersunk into the table, and secured 'vrith taps beneath (/^. 865), the edg« of the knife being placed horizontally over the opening^, and parallel with it. In Jig. 865, the leather, k, is shown advancing against the knife, getting split, and has a portion coiled round the cylinder, which is made to revolve in proportion as the leather is cleft The upper portion of the leather is rolled upon tlie cyhnder d, while the under halt /, falls through the oblong opening upon the ground. In regulating the thickness of the split leather, the two supports, wi, act ; they are made fast to the table a (one on each side of the knife), and are mortised into the table by two tenons secured beneath. These supports are furnished near their tops with keyed slots, by means of which the horizontal iron rod o {Jigs. 863, 865,) is secured, and outside of the uprights they press upon the springs /)p, which tend to raise the rod, o, in its two end slots; but the adjusting screws 9, which pass down through the tops of the supports into the mortise n {Jig. 865), and press upon the upper half of the divided tenon, counteract the springs, and accordingly keep the rod, 0, exactly at any desired height or level The iron rod, o, carries another iron bar, r, beneath it, parellel and also rectangular, Jig. 865. This lower bar, which is rounded at its under face, lies upon and presses the leather, by the action of two screws, which pass through two upright pieces s{Jig». 863, and 865,) made fast to the table; thus the iron bar, r, may be made to press forwards the edge of the knife, and it may be adjusted in its degree of pressure, according to the desired thickness of the leaf of split leather, that passes through under it Fig. 865, shows that the slant or obliquity of the knife is directed downwards, over one of the edges of the oblong opening g ; the other edge of this opening is provided with an iron plate t {Jigs. 865, 866), which serves to guide the blade in cutting the leather to the proper depth. For this purpose the plate is made adjustable by means of the four springs u {figs 865, 866), let into the table, which press it downwards. Four screws, v, pass down through the table, each belonging to its respective springs u, and by means of these screws the plate, t, may be raised in any desired degree. Each of the screws, u, has besides a small rectangular notch through which a screw bolt, x, passes, by which the spring is made fast to the table. Thus also the plate, t, may be made to approach to or recede from the knife. y, in^». 863, and 865, is a flat board, laid upon the leather a little behind the edge of the plate t; this board is pressed by the cylinder z, that lies upon it and whose tenons rest in mortises cut out in the two supports a'. The cylinder, z, is held in its position by a wedge or pin b {Jigs. 863, and 864), which passes through the supports. When the leather has been split these pins are removed, and the cylinder rises then bj means of the two counter weights, not shown in the figures. The operation of the machine is as follows ; — ^The edge or end of the leather being secured to the cylinder d, the leather itself having the direction upon the table shown in^^f. 865, and the bar, r, its proper proportion over the knife, the edge begins to enter in this position into the leather, while tlie cylinder, d, is moved by the handle or winch, and the piece gets split betwixt the blade and the roller d. When the other end of the leather, k, advances to the knife, there is, consequently, one half of the leather split; the skin is to be then rolled off the cylinder d; it is turned; the already split half, or the end of the leather k, is made fast into the wood of the cylinder, and the other half is next split ; while the knife now acts fi*om below, in an opposite direction to what it did at first That the unrolling of the leather from the cylinder, d, may not be obstructed by the pinion t, the stop-wedge e{Jig8. 863, 864) is removed from the teeth. In the process of splitting, the grain side of the leather is uppermost and is therefore cut of an uniform thickness, but the underside varies in thickness with the inequality of the skin. The quantity of leather gloves of Foreign production exported in 1850, was 401,009 pairs, and in 1851, 107,925 pairs. See Hides. Exports of Leather of British Produce and Manufacture. Quantities. Declared Value. £ JE 1860. 1851. 1850. 1861. 32,205 25,625 181,737 152,070 81,124 27,141 18,821 19,781 1,619,463 1,625,566 284,847 288,543 — — 123,960 138,168 Leather, nnwrought cwts. Wrought viz. gloves, lbs. Of other sorts, lbs. . Saddlery and harness, value £ LEDUM PELUSTRE This plant is employed in Russia to tan the skin of goats, ealyes, and sheep, into a reddish leather of an agreeable smell ; as also in the prepara- tion of the oil of birch, for making what is commonly called Russia leather. LEGUMINE^ is the name of a vegeto-alkali supposed to exist in leguminous plants. LEMONS. See Citric Acid, and Oils, Essential. LEVIGATION is the mechanical process whereby hard substances are reduced to a ▼ery fine powder. LELJCITE is a hard Yesuvian mineral, consisting of silica, 54 ; alumina, 23 ; pot- ash, 23. LEUCINE is a white crystalline substance produced by acting upon flesh with sulphu- ric acid. LEWIS is the name of one kind of shears used in cropping woollen cloth. LIAS is a fine-grained argillaceous limestone, whose geological position is under the oolite ; it is the proper lithographic stone. LIBAVIUS, LiquoR of, is the bichloride of tin, piepared by dissolving that metal, with the aid of heat, in aqua regiay or by passing chlorine gas through a solution of muriate of tin till no more gas be absorbed, evaporating the solution, and setting it aside to crys- tallize. The anhydrous bichloride is best prepared by mixing four parts of corrosive sub- limate with one part of tin, previously amalgamated with just so much mercury as to render it pulverizable ; and by distilling this mixture with a gentle heat. A colorless fluid, the dry bichloride of tin, or the proper fuming liquor of Libavius, comes over. When it is mixed with one third of its weight of water it becomes solid. The first bichloride of tin is used in calico-printing. LICHEN. See Archil. LIGNEOUS MATTER is vegetable fibre. See Fibrous Matter. LIGNITE is one of the most recent geological formations, being the carbonaceous remains of forest trees. From this substance, as found in the neighborhood of Cologne,- the brown colors, called timber and earth of CologiiBj are prepared. LILACH DYE. See Calico-printing and DYEiNr+, LIMESTONE (Ca/cairc,Fr.;ira/4fet7etn, Germ.), may be classed under the following heads : — 1. Calcareous spar occurs in colorless crystals or crystalline masses ; dissolves with effervescence in muriatic acid ; is scratched by soft iron, but not by the nail ; specific gravity 2*7 ; loses 46 per cent, by the expulsion of carbonic acid, and calcines into quick- lime. 2. Calcsinter, or stalactitic carbonate of lime, called also concretionary limestone, because formed of zones more or less undulated, and nearly parallel. These zones have a fibrous structure, arising from the successive deposites of the crystalline limestone from its sol- vent water. The long conical pieces called stalactites, show fibres converging to the axis. The tubercular consists of irregular lumps often sprinkled over with small crystals, and associated so as to exhibit the appearance of cauliflower. The stratiform, commonly called stalagmite, or alabaster limestone, represents zones not concentric, but spread out, waving, and parallel ; its texture is sometimes lamellar, and sometimes fibrous. These waving strata are distinguishable from one another by their diflferent densities, and by their degrees of translucency. This stalagmitic mass bears the name of oriental alabaster, when it is reddish-yellow with distinct zones, and is susceptible of a fine polish. Stalac- tites are formed in the large excavations of calcareotc rocks. The water percolating down through them, and dropping from the roofs of the caverns, is usually charged with carbonate of lime held in suspension by an excess of carbonic acid. The exposure to air, the motion, and the consequent diminution of pressure, cause the precipitation of the car- bonate of lime in the solid state. Each drop of water, on falling through the vault, aban- dons a small film of limestone, which enlarges by degrees, and forms either a cylinder or solid mass. This alabaster difiers from marble in its parallel and waving layers, and its famt degree of transparency. This alabaster serves for the decoration of public buildings, and is occasionally intro- duced into certain pieces of furniture. The fine Egyptian alabaster was anciently brought from the mountains of the Thebaid, between the Nile and the Red Sea, near a town called Alabastron, whence probably the name. Very fine red alabaster, of great exha ted^*^ *^ °"^ ^^ ^^ ^^^ quarries of Montmartre, but the stock was soon The incrusting concretionary limestone differs little from the preceding except in ine rapidity of its formation, and in being moulded upon some body whose shape it assumes. Ihese deposites from calcareous springs, form equaUy on vegetable bodies, on siones, metals mthm pipes of cast iron, wood, or lead. The incrustations on vegetable ana animal substances are vulgarly caUed petrifactions, as the organic fibres are replaced oy sione. une of the most curious springs of this nature is at the baths of Saint PhiUp, «l»Lct ^^\- u"® *?® ^^^^"^ ^^"^^ ^^ *l"«st a boiUng state, over an enormous mass oi hlro K, ^1 i ** i"^^ produced. The carbonate of lime seems to be held in solution vIL^l *u Phureted hydrogen, which flies off" when the water issues to the day. Dr. of arirLV? advantage of this property of the spring, to obtain basso-reUevo figures Of great whiteness and soUdity. He makes use of sulphS- moulds. / T> LIMESTONE. LIMESTONE. 73 ti i^t |i ill Calcareous tuf consists of similar incrustations made by petrifying rirulets running over mud, sand, vei^etable remains, &,c. It is porous, even cellular, somewhat soft, impure, and of a dirty gray color. Its surface is wavy, rough, and irregular. These incrustations or deposites are, however, sometimes so abundant, and the resulting stony matters so hard that buildings may be constructed with them. The stone with which the town of Pasti, in Italy, is built has been called pipe-stone by the Italians ; and it has ap- piirently derived its origin from incrustations upon large reeds. The travertinOy which served to construct all the monuments of Rome, appears to have been formed by the deposites of the Anio and the solfatara of Tivoli. The temples of Paestum, which are of extreme antiquity, have been built with a travertino formed by the sediment of the waters which still flow in this territory. All these stones acquire great hardness in the air, and M. de Breislak thinks that it is to the happy union of travertino and pouzzolana in the same spot, that the monuments of Rome owe their great solidity. Spongy limeslone, usually called jlgaric mineral^ stone marrow, &c., belongs to this kind of formation. It has a very white color, a very fine grain, is soft to the touch, very tender, and light enough to float for an instant on water. It occurs in rather thin layers, in the crevices of calcareous rocks, and is so common in Switzerland as to be employed for whitening houses. 3. Compact limestone, is of a grain more or less fine, does not polish, nor afford large blocks free from fissures, has a conchoidal, or uneven scaly fracture. Colors very various. Its varieties are ; a. The sub-lamellar, compact, with some appearance of a foliated texture, b, Compact fine-grained limestone, the zechstein of the Germans, to which M. Brongniart refers the lithographic stone in his classification of rocks (Dictum' nairt des Sciences Naturelles), but the English geologists place the locality of tht iamoug lithographic quarry of Solenhofen much higher in the plane of secondary superposition. Its fracture is conchoidal ; color from gray to whitish ; c. Compact common limestone. Grain of middle size ; earthy aspect ; uneven fracture ; perfectly opaque ; color, whitish to pale gray, yellow, or reddish. The limestones of the Jura formation are referred to this head, as well as most of those interspersed among the coal strata, d. The coarse compact, or Cornbrash ; texture somewhat open, earthy aspect, rough to the touch, ragged fracture, color yellow, gray, or dirty red. e. Compact cellular, the Rauchekalk and Holekalk of the Germans, on account of the numerous holes or caverns distributed through it. 4. Oolite or roe-stone. — It consists of spherical grains of various size, from a millet seed, to a pea, or even an egg ; texture compact ; fracture even ; colors, whitish, yellow, gray, reddish, brownish. The larger bails have almost always a foreign body for their centre or nucleus, 5. Chalk ; texture earthy ; grains fine, tender, friable ; colors white, grayish, or pale yellowish. 6. Coarse-grained limestone ; an earthy texture, in large particles, often loose ; frac- ture foliated, uneven ; color pale and dirty yellow. Coarse lias has been referred to this head. 7. Marly limestone ; lake and fresh water limestone formation ; texture fine-grained, more or less dense ; apt to cnimble down in the air ; color white or pale yellow ; fracture rough-grained, sometimes conchoidal ; somewhat tenacious. Texture occasionally cavern ous ; with cylindrical winding cavities. This true limestone must not be confounded with the lime-marl, composed of calcareous matter and clay. 8. Silicious limestone; of a compact texture; scratching steel, and scratched by it ; leaves a silicious residuum after the action of muriatic acid. 9. Calp ; texture compact ; fine-grained ; schistose structure ; bard, as the pre- ceding ; not burning into quicklime, affording to dilute muriatic acid a copious residuum of clay and silica ; color blackish ; found in beds in the transition district near Dublin. 10. Lucullite or stinkstone ; texture compact or sub-lamellar, color gr»yish ; emits the smell of sulphureted hydrogen by friction or a blow. It occurs at Assynt, in Sutherland- shire ; in Derbyshire ; counties of Kilkenny, Cork, and Galway. \l. Bituminous limestone; black or blackish color; diffusing by the action of fire a bituminous odor, and becoming white. Of all common limestones the purity may most readily be determined by the quantity of carbonic acid which is evolved during their solution in dilute nitric or muriatic acid. Perfect carbonate of lime loses in this way 46 per cent. ; and if any particular limestone loses only 23 per cent., we may infer that it contains only one half its weight of calcareous carbonate. This method is equally applicable to marls, which are mixtures in various proportions of carbonate of lime, clay, and sand, and may all be recognised by their effer- vescing with acids. The chief use of calcareous stones is for procuring quicklime by calcination in propel fumaces; and they are all adapted to this purpose provided they are not mixed with too large a proportion of sand and ferruginous clay, whereby they acquire a vitrescent texture in a high heat, and will not burn into lime. Limestone used to be calcined in a very rude kiln, formed by enclosing a circular space of 10 or 15 feet diameter, by rude stone walls 4 or 5 feet high, and filling the cylindrical cavity with alternate layers of turf or coal and limestone broken into moderate pieces. A bed of brushwood was usually placed at the bottom, to facilitate the kindling of the kiln. Whenever the com- bustion was fairly commenced, the top, piled into a conical form, was covered in with sods, to render the calcination slow and regular. This method being found relatively inconvenient and ineffectual, was succeeded by a permanent kiln built of stones or brick- work, in the shape of a truncated cone with the narrow end undermost, and closed at bottom by an iron grate. Into this kiln, the fuel and limestone were introduced at the top in alternate layers, beginning of course with the former ; and the charge was either allowed to bum out, when the lime was altogether removed at a door near the bottom or the kiln was successively fed with fresh materials, in alternate beds, as the former supply sunk down by the calcination, while the thoroughly burnt lime at the bottom was succes- sively raked out by a side door immediately above the grate. The interior of the lime kiln has been changed of late years from the conical to the dliptical form ; and probably the best is that of an egg placed with its narrow end undermost, and truncated both above and below ; the ground plot or bottom of the kiln being compressed so as to give an elliptical section, with an eye or draft-hole towards each end of that ellipse A kiln thus arched in above gives a reverberatory heat to the upper materials, and also favors Iheir falling freely down in proportion as the finished lime is raked out below; advan- tages which the conical form does not afford. The size of the draft-notes for extracting the quicklime, should be proportionate to the size of the kiln, in order to admit a suffi- cient current of air to ascend with the smoke and flame, which is found to facilitate the extrication of the carbonic acid. The kilns are called perpetual, because the operation w cairied on continuously as long as the building lasts ; and draw^ilns, from the mode of discharging them by raking out the lime into carts placed against the draft-holes. Three bushels of calcined limestone, or lime-shells, are produced on an average for every bushel of coals consumed. Such kilns should be built up against the face of a cliff, so that easy access may be gained to the mouth for charging, by making a sloping cart road to the too w the bank, '^ ■-•ft :«•»*• 3a, '-^i^ 74 LIMESTONE. LIQUATION. 7S 2^ff- 167, 868, 869, 8T0, represent the lime-kiln of Rudersdorf near Berlin, upv.a the continuous plan, excellently constmcted for et-onoraizing fuel. It is triple, and yields a threefold product. Fiff. 869, is a view of it as seen from above; Jig. 87(), the elevation and general appearance of one side ; Ji^. 867. a vertical section, and Jig. 868, the ground plan in the line a bod of/^. 867. The inner shaft Jig. 868. has the form of two tinincated cones, with their larger circular ends applied to each other ; it has the greatest width at the level of the fire-door b, where it is 8 feet in diameter ; it is narrower below at the discharge door, and at the top orifice, where it is about 6 feet in diameter. The interior wall d, of the upper shaft, is built with hewn stones to the height of 38 feet^ and below that for 26 feet, with fire-bricks d' d', laid stepwise. This inner wall is surrounded with a mantle e, of limestone, but between the two there is a small vacant space of a few inches filled with ashes, in order to allow of the expansion of the interior with heat taking place without shattering the mass of the building. The fire grate, b, consists of fire-tiles, which at the middle, where the single pieces press together, lie upon an arched support /*. The fire-door is also arched, and is secured by fire-tiles, g is the iron door in front of that orifice. The tiles which form the grata have 3 or 4 slits of an inch wide for admitting the air, which enters through the canal A. The under part of the shaft from the fire to the hearth is 7 feet, and the outer enclosing wall is constructed of limestone, the lining being of fire-bricks. Here are the ash-pit t, the discharge outlet a, and the canal k, in front of the outlet. Each ash-pit is shut with an iron door, which is opened only when the space i becomes filled with ashes. These indeed are allowed to remain till they get cool enough to be removed without incon- Tenience. The discharge outlets are also furished with iron doors, which are opened only for taking out the lime, and are carefully luted with loam during the burning. The outei walls / m n of the kiln, are not essentially necessary, but convenient, because they afibrd room for the lime to lie in the lower floor, and the fuel in the second. The several stories are formed of groined arches o, and platforms j>, covered over with limestone slabs. In the third and fourth stories the workmen lodge at night. See Jig. 870. Some enter their apartments by the upper door q ; others by the lower door s. r is one of the chimneys for the several fire-places of the workmen, t uv are stairs. As the limestone is introduced at top, the mouth of the kiln is surrounded with a strong iron balustrade to prevent the danger of the people tumbling in. The platform is laid with rails u", for the wagons of limestone, drawn by horses, to run upon, x is another rail-way, leading to another kiln. Such kilns are named after the number of their fire-doors, single, twofold, threefold, fourfold, &c. ; from three to five being the most usual. The outer form of the kiln also is determined by the number of the furnaces ; being a truncated pyramid of equal sides ; and in the middle of each alternate side there is a fire, place, and a discharge outlet. A cubic foot of limestone requires for burning, one and five twelfths of a cubic foot of wood, and one and a half of turf. When the kiln is to be set in action, it is filled with rough limestones, to the height c D, or to the level of the firing; a wood fire is kindled in «, and kept up till the lime is calcined. Upon this mass of quicklime, a fresh quantity of limestones is introduced, not thrown in at the mouth, but let down in buckets, till the kiln be quite fuU ; while over the top a cone of limestones is piled up, about 4 feet high. A turf-fire is now kindled m the furnaces b. Whenever the upper stones are well calcined, the lime under the fire-level is taken out, the superior column falls in, a new cone is piled up, and the process goes on thus without interruption, and without the necessity of once putting a fire into a; for in the space c b, the lime must be always well calcined. The discharge of lime takes place every 12 hours, and it amounts at each time in a threefold kiln, to from 20 to 24 Prussian tonnes of 6 imperial bushels each ; or to 130 bushels imperial upon the average. It is found by eyperience, that fresh-broken limestone which contains a little moisture, calcines more readily than what has been dried by exposure for some time to the air ; in consequence of the vapor of water promoting the escape of the carbonic acid gas ; a fact well exemplified in distilling essential oils, as oil of tur- pentine and naptha, which come over with the steam of water, at upwards of 100 degrees F. below their natural term of ebullition. Six bushels of Rudersdorf quickhme weigh from 280 to 306 pounds. When coals are used for fuel in a well-constructed perpetual, or draw kiln, about ] measure of them should suffice for 4 or 5 of limestone. The most extensive employment of quicklime is in agriculture, on which subject in- structive details are given in Loudon's Encyclopaedias of Agriculture and Gardening. Quicklime is employed in a multitude of preparations subservient to the arts ; for clarifying the juice of the sugar-cane and the beet-root; for purifying coal gas; for rendering the potash and soda of commerce caustic in the soap manufacture, and in the bleaching of linen and cotton ; for purifying animal matters before dissolving out their gelatine ; for clearing hides of their hair in tanneries ; for extracting the pure volatile alkali from muriate or sulphate of ammonia ; for rendering confined portions of air very dry; for stopping the leakage of stone reservoirs, when mixed with clay and thrown into the water ; for making a powerful lute with white of egg or serum of blood; for preparing a depilatory pommade with sulphuret of arsenic, ' ^^ P^"''^^ ^^ «P"'i^s <>f 1«° ^-^ ^ Pounds of white sugar, and 4 oS^^. 1/7? '"'''•*"''•. ^^^'^^ ^^^ ""g'^^ ^« dissolved, add a sufficient quantity of the ^muX^lZ K ?/'-^ ^^"^T' ^^^" 'P^<^« *^« ^^°1« ^ith 48 grains of cinnamon, and i^fa«« di^fn • 1 r? J' '"" ^'^^^''- ^^'^^y introduce an ounce of ground Brazil wood, and given w"th caramel'' agitating 3 or four times daily. A pretty deep hue ought to b« Synss extract of wormwood, is compounded as follows:— lops ot the absmthium majus 4 pounds ; Ditto, absinthium minus 2 pounds ; / I 1*' I I. 78 LITHOGRAPIUC PRESSES. 'of each a few grains at pleasure; Roots ot angelica, Calamus aromaticus, Seeds of the anUum ChitUBy Leaves of the dittany of Crete, ^ Alcohol of 20° B., four gallons Imp. ^ ,. ., . n a a ™«fff^A Macerate these substances during eight days, then distil by a gentle fire ; draw off two gallons of spirits, and add to it 2 drachms of essential oil of anise-seed. The two gallon* left in the still serve for preparing the vulnerary spirituous water. Of coloring the liqueurs. . n / ^i. \ v-i. ;- Yellow is given with the yeUow coloring matter of sunflower {earthamus), which w readily extracted by water. , , ., Fawn is given by caramel, made by heating ground white sugarm an iron spoon over a charcoal fire, till it assumes the desired tint, and then pounng it into a little cold water. t i i Jied is given by cochineal alone, or with a little alum. Violet is given by good litmus (turnsole). . ^, . .. -i. i -xv Blue and orecn.— Sulphate of indigo gives the fii-st. After saturating it nearly with chalk, alcohol being digested upon it, becomes blue. This tincture mixed with that of earth amus forms a good green. LIQUIDAMBER, is obtained from the liquidamhar styractjlua, a tree which grow§ in Mexico, Louisiana and Virginia. Some specimens are thin, like oil, and others are thickish, like turpentine. It is transparent, amber colored, has an agreeable and power- ful smell, and an aromatic taste, which feels pungent in the throat. Boiling alcohol dissolves it almost entirely. It contains a good deal of benzoic acid, some of which effloresces whenever the liquidamber hardens with keeping. . . , , , , LITHARGE (Eng. and Fr. ; Glatte, Germ.) ; is the fused yellow protoxide of lead, which on cooling passes into a mass consisting of small six-sided plates, of a reddish yellow color, and semi-transparent It generally contains more or less red lead, whence the variations of its color; and carbonic acid, especially when it has been exposed to the air for some time. See Lead and Silver, for its mode of preparation. LITHIA, is a simple earthy or alkaline substance, discovered not many years ago in the minerals called petalite and tiphane. It is white, very caustic, reddens litmus, and red cabbage, and saturates acids with great facility. When exposed to the air it attracts humidity and carbonic acid. It is more soluble in water than baryta ; and has such a strong affinity for it as to be obtained only in the state of a hydrate. It forms neutral salts with all the acids. It is most remarkable for its power of acting upon or corroding platinum. • i. r ,«/^ * LITHIUM, is the metallic basis of lithia ; the latter substance consists of 100 of metal, and 123 of oxygen. . i. i v LITHOGRAPHIC PRESS. The lithographic press m common use has long been regarded as a very inadequate machine. The amount of manual power required to work it, and the slow speed at which, under the most favorable circumstances, copies can be produced, disables lithography in its competition with letter-press. A career of brilliant success has attended the efforts of scientific men towards speed and per- fection in this latter branch of the art ; and the present printing machines surpass the hand-press somewhat in the same ratio, as does our express speed the jog trot of our forefathers. The engravings annexed will serve to illustrate Messrs. Napier A Sons 874 improvements upon the lithographic pre.«s. The machine i.s arranged to be driven by steam m»wer; has belts, " crc.ssed " and "open," supposed to be in connection with the engine, and to run upon the pulleys a, u, c. The crank pulley, b, is fixed on the screw LITHOGRAPHY. 79 epindle d, and the other two work loose, or " dead," on the same spindle ; these bands with their striking forks, a, are arranged so as to be brought alternately upon the fixed pulley, b, and thus a reversing motion is given to the screw. The nut in which the screw works is fixed to a crosspiece e, which braces the side frames f, f, together at bottom, while the bar g, performs the same oflice at top ; the scraper box, h, is sustained between these frames at bearings i, and is so fitted as to work freely. To support the frames and scraper box independent of the screw, and maintain them in position, allow- ing freedom of action, the rollers j, j, are provided, which run in the planed recesses, K, along the top of the main standards l. The machine is shown with its tympan down, ready for starting ; this is effected by pressing lightly upon the lever, 6, which raises a catch, and allows the weight m, to descend in the direction of its present inclination, and act upon the connections with the striking forks, so as to bring one of the bands upon the fast pulley b, and make the scraper and its frames move forward. Tlie return is caused by the frame f, coming in contact with a stop c, which yielding, acts upon the striking forks by its bar cf, upon which it may be adjusted to give the travel required. On the return being accomplished the machine stops itself by a striking action against stop e, the catch 6, falling in to prevent the weight descending to its full throw, and thus retaining the two bands upon the two dead pulleys, a and c, while the machine is prepared for another impression. The action of the scraper is peculiar and novel ; it is balanced, so that its tendency is to remain slightly raised, but in its forward movement, and at the point desired, it is made to descend by a stop fixed upon the top of the main standard, l, into a position vertical or nearly so, in which position it is retained by its own onward progress against strong abutments projecting from the frames, f ; on the return it resumes its raised posi- tion and passes back without impediment The scraper may be adjusted to give the pressure desired, or the table on which the stone is placed regulated by screws. The advantages embodied in this machine will be at once recognized by those in- terested. The pulling down of the sci-aper, and the labor and inconvenience attendant upon that operation, are entirely superseded by the simple and effectual valve-like movement just explained, which forms the groundwork of this combination, although it will alike apply to the press-work by hand, and is the most striking novelty in Uie machine. LITHOGRAPHY. Though this subject belongs rather to the arts of taste and design than to productive manufactures, its chemical principles fall within the province of this Dictionary. The term lithography^ derived from \i6oi a stone, and ypav, writing, and designates the art of throwing off impressions upon paper, of figures and writing previously traced upon stone. The processes of this art are founded : — 1. Upon the adhesion to a smoothly-polished limestone, of an encaustic fat which forms the lines or traces. 2. Upon the power ac\«re to be aided after they are taken oflF the fire, and Waok isTo'hl w.n1 f'^'^^'f' ea?P «h*^i«g« «-« to be thrown in. Lastly the^amp black is to be well intermixed. Whenever the union is accomplished by heat Se tLlled or nver water. Jt should be flowing in the pen, not spreading on the st^n J: ca m-" ble of forming delicate traces, and very black to show its delineations The most es^in tial quality of the ink is to sink well into the stone, so as to re-prXce the m^t delica e ou hnes of the drawing, and to aflbrd a great man^ impressions It^u.t TheVefore b! able to resist the acid with which the stone is moistened in the preparat on without let! tmg any of its greasy matter escape. cp*iiaiiun, ^Minoui lei- prefeVl^e rolrfolwL"" """"^ '"'^ " ^™' '""'^ combinations, he gives .he Tallow soap, dried - Mastic, in tears White soda of commerce Shellac Lamp-black - 30 parts 30 — 30 — 150 — 12 — « JJi r^ *• ^^'/"' /''*'' ^^^ ^?^^^^ *"^ '"^It^ over the fire, to which the lac being added fuses immediately ; the soda is then introduced, and next the mastic, stirrin- aU ^tZt r' .K '^v!"^- ^ ^'^J" ^'^. '' ^PP"^^ ^"1 ^» these materials be melted com- pletely, when the whole is poured out into the mould. The inks now prescribed may be employed equaUy with the pen and the hair pencil for writings, black-lead drawings, aqua tinta, mixed drawings, those which represent en! gravings on wood (wood cuts), &c. When the ink is to bemused it is to be rubbed down with water, m the manner of China ink, till the shade be of the requisite depth. The TS '^ ^.^A ^1^' M*'".^^' ^°>^ ^"^^^ ^^° ^« ^^ ^'^•^^M «^ tl^e saucer in which the than IS to be used at the time, for it raiely keeps in the Hquid state for 24 hours ; and it BQouId be covered or corked up. ' ^utographic paper.— Autogmphy, or the operation by which a writing or a drawing is fransferred ^om paper to stone, presents not merely a means of abridging labor, but dso ^at of reverting the writmgs or drawings into the direction in which they we^e traced, whilst. If executed directly upon the stone, the impression given by it is inverted. Henc? nZ'T^ J^^T '^^'"^ "'?' ^^ '""l^'^^^ ^"^'^ "-*^t t° ^^ft to obtain direct impressions! But the art of writmg thus is tedious and difficult to acquire, while, by means of the autographic paper and the transfer, proofs are obtained in the same direction with the writing and drawing. .^tt/ograp/iic nife.-It must be fatter and sof\er than that appUed directly to the stone, BO that though dry upon the paper, it may still preserve sufficient viscidity to stick to the stone by mere pressure. -. »« vuc To compose this ink, we take — White soap ... White wax of the best quality Mutton suet ... Shellac .... Mastic .... Lamp-black - - . - 100 parts 100 — 30 — 60 — 50 — 30 or 35 — . These materials are to be melted as above described for the Uthographic ink. LUhographic ink and paper.-The foUowing recipes have been much commended :- Virgin or white wax 8 parts White soap ...... 2 Shellac ---....2 Lamp-black " 3 table-spoonsfm. hoflftn''?ntr'^P^h7r ^"i^^^P.^e to be melted together, and before they become so hot as to take fire the lamp-black is to be well stirred in with a spatula, and then the SJf .i'i^^^^"'^''''^ ^^ ^J"" ^°' 30 ^^^«"^«5 the flame being extinguished, the lac i^ to be added by degrees, carefully stirring all the time ; the vessll is to^be put upo^ the k[nTH Z"" °^^e[ to complete the combination, and till the materials are either li ?1P fjr" ^ r- ♦ ^^^ the flame is extinguished, the ink must be suffered to cool a utile, and then put into the moulds. Vol, XL « 82 LIXIVIATION. LUBRICATION. 83 •1 ! I I !l >■ ! i lull I t ii«i With the ink crayons thns made, lines may be drawn as fine as with the point of the graver, and as full as can be desired, without risk of its spreading in the carriage. Its traces will remain unchanged on paper for years before being transferred. Some may think it strange that there is no suet in the above composition, but it has been found that ink containing it is only good when u?ed soon after it is made, and when immediately transfeired to the stone, while traces drawn on paper with the suet ink be- eome defective after 4 or 5 days. Lithographic paper. — Lay on the paper, 3 successive coats of sheep-feet jelly, 1 layer of white starch, 1 layer of gamboge. The first layer is applied with a sponge dipped in the solution of the hot jelly, very equally over the whole surface, but thin ; and if the leaf be stretched upon a cord, the gelatine will be more uniform. The next two coats are to be laid on, until each is dry. The layer of starch is then to be applied with a sponge, and it will also be very thin and equal. The coat of gamboge is lastly to be applied in the same way. When the paper is dry, it must be smoothed by passing it through the lithographic press ; and the naore polished it is, the better does it take on the ink in fine lines. Trantfer. — When the paper is moistened, the transfer of the ink from the gamboge is perfect and infallible. The starch separates from the gelatine, and if, after taking the paper off the stone, we place it on a white slab of stone, and pour hot water over it, it will resume its primitive state. The coat of gamboge ought to be laid on the same day it is dissolved, as by keeping it becomes of an oily nature ; in this state it does not obstruct the transfer, but it gives 8 gloss to the paper which renders the drawing or tracing more difficult, especially to per- sons little habituated to lithogiaphy. The stareh paste can be employed only when cold, the day after it is made, and after having the skin removed from its surface. A leaf of such lithographic paper may be made in two minutes. In transferring a writing, an ink drawing, or a lithographic crayon, even the impression of a copper-plate, to the stone, it is necessary, 1. that the impressions be made upon a thio and slender body like common paper ; 2. that they may be detached and fixed totally on the stone by means of pressure ; but as the ink of a drawing sinks to a certain depth in paper, and adheres pretty strongly, it would be difficult to detach all its parts, were there not previously put between the paper and the traces, a body capable of being separated from the paper, and of losing its adhesion to it by means of the water with which it is damped. In order to produce this effect, the paper gets a certain preparation, which con- sists in coating it over with a kind of paste ready to receive ev«7 delineation withoiit suffering it to penetrate into the paper. There are different modes of communicating this properly to paper. Besides the above, the following may be tried. Take an unsized paper, rather strong, and cover it with a vami^ composed of: — Starch ... - - 120 parts Gum arable - - - ' - - 40 — Alum - - - • • 20 — A paste of moderate consistence must be made with the starch and some water, with the aid of heat, into which the gum and alum are to be thrown, each previously dissolved in .separate vessels. When the whole is well mixed, it is to be applied, still hot, on the leaves of paper, with a flat smooth brush. A tint of yellow color may be given to the varnish, with a decoction of the berries of Avignon, commonly called French berries by cm- dyers. The paper is to be dried, and smoothed by passing under the scraper of the lithographic press. Steel pens are employed for writing and drawing with ink on the lithographic stones. LITMUS (Tmrmsol, Fr. ; Lackmus, Germ.) is prepared in Holland from the species of lichen called Lecanora tartarea, Roccella tartareay by a process which has been kept secret, but which is undoubtedly analogous to that for making archil and cudbear. The ground lichens are first treated with urine containing a little potash, and allowed to fer- ment, whereby they produce a purple-red ; the colored liquor, treated with quicklime and some more urine, is set again to ferment during two or three weeks, then it is mLxed with chalk or gypsum into a paste, which is formed into small cubical pieces, and dried in the shade. Litmus has a violet-blue color, is easy to pulverize, is partially soluble in water and dilute alcohol, leaving a residuum consisting of carbonate of lime, of clay, silica, gypsum, and oxyde of iron combined with the dye. The color of litmus is not altered by alkalis, but is reddened by acids ; and is therefore used in chemistry as a delicate test of acidity, either in the state of solution or of unsized paper stained with it. It is employed to dye marble blue. LIXIVIATION (Lessivage, Fr. j Juslagen, Germ.) signifies the abstraction by wate. of the soluble alkaline or saline matters present in any earthy admixture ; as from that of qu.ckhme and potashes to make potash lye, rfom thit of effloresced alum schist to make aluminous liquors, Ac rim'll^f^-^^ MAGNETIC IRON-STONE (i^.r oxydule, Fr. ; Magneteisenstein, fombinathm ^'''^ ««°««tmg of the protoxide and peroxide of iron in a state of on^?^ ^^''''' /tmonm*^, Fr ; Lekm, Germ.); a native clay mixed with quartz sand and iron ochre, and occasionally with some carbonate of lime kPv^S^.^j?f ^^ ^^^^^- * J^,^ P«<^«lif "ty of this lock consisis in an extension of the key aftei it is inserted m the lock, and a secret connection between the interior of the key and two of the players. The two inclined planes on the under side of tTe wards open or shut the extension of the key as it passes over them : the part of the key thus extended operates on two players placed beyond the reach of picklocks, while at th« same time the mam part of the key works other two players, which are again operated on by the secret apparatus in the interior of the key. This secret ap?irtus^cln be removed at pleasure, and the proper key then becomes unfit to work the lock and skeleton kep however well fitted to pass the wards, will not operate on the players LODE, IS the name given by the Cornish miners to a vein, wLther it be filled with metallic or earthy matter. ^ "'" //if ^^^^^^^^''** t ^«^^^^^^' ^o'' *^^«' Fr- ; ^l^^hoh, Germ. ; is the wood of the mtmatoxylon Campecnanum a native tree of central America, grown in Jamaica since Ilk \^« *^f V°^'^*^^'f^ '"*.^ ^"S^^"^ ^" ^^^ ^^'^» of Elizlbeth. but as it afforded to the unskilful dyers of her time a fugitive color,"it was not only prohib ted from being used under severe penalties, but was ordered to be burned wherever found hZ tl ^""""^f T ^^' '^^^ ny ^^^"'* '•''^"- "^''^ ^^"^^ P^^J"^'«« existed, and the Tme tw was enacted against indi^o. At length, after a c/ntury of absurd prohibition thes^ two most valuable tinctorfal matters, by which all our hats, and tlfe greater part of our woollen cloths are dyed, were allowed to be used greater part of ^f ^'^,'^r'^' "^'^u ^^^""^ '^^""^ *"^ "^'^^ ^'^**e «^ ^^^ ^^ite alburnum, is preferred Log- wood is denser than water, very hard, of a fine compact grain, and almost inditmct For its chemical composition, see Hemativ When chipped logwood is for some time exposed to the air, it loses a portion of its dyeing power. Its decoction absorbs the oxvgenof the atmosphere and then aem,i,pt the property of precipitating with gelatine, Vhich it had not before. TTie dry extract of logwood, made from an old decoction, affords only a fugitive color. ^ i>r:LT^fB^^z:ii '^""^' "^ ""^^^^ ^^'^^ ^«^-^ ^-^ ^-- 1-™; q 'T^'r^i"'^'""*^ olt^^''''^ ^^"^ .^° }^^^' ^^'^^^ *«"«; i" 1851, 21,240 tons: of which ' T AA^?^*,'^^ ^'^^^ ^""^ respectively were re-exported. monv /''•'' '^**T'/^•^ ^<^f>^rstuhl. Germ.); is the ancient and well-known machine for weaving cloth by the decussation of a series of parallel threads which Z lengthwise called the warp or chain, with other threads thrown transversely wTth ^e T tt^'t,?"^*^ *^'^ ^*^^ **'• ^^^^^^ See Jacquard Loom Weaving ^ ioint^^^i >f^'-^^- 7^'^ ?"^^"l^ ^"-"J?^" ^°^ efficacious plan of lubricating the iXd to 1 w'?f •' "^.^^^"^^'•^^ ^y '^P^^^y attraction, has been kindly comm4i- cat^d to me, by its ingenious inventor, Edward Woolsey Esq •— "i»nuHi fi, if'i • '■eP'i^^ents a tin cup, which has a small tin tube a, which Da<«se8 through tnb^' J ^^P;^'«ry/tt,ractK)n causes the oil to ascend and pass over the orifice of the lenVo The%hrJ:d'" *"', '^^^^^ slower or q^iicker, acc::di;g to t : lengin ot the thread or its thickness, until every particle of oil is drawn over bv th ! capillary svphon. The tube is intended to be put into the bearings of shaft' x/ ^'d 18 made of any size that may be wished. If oil, or other liquid LdeSed t^^Z ^eflin^"^ ''' ^^^- -'•^-^' ^^^^ -P -" havTl'^and?:!': it t It ""^ S^ ^"^^ preventing the oil from passing. and mowlteVrinL'^IhlTfh^'' '''• ^ ^^Mfff-.^l^ are used upon beams of engines I thi^t "e act^oTff'tt ! '"'^^ isapt to be tightened by the motion ; and alfo as dowr? Jffi«: Vi •/ ^'""T '* ""certain, from the workmen ne^lectini to screw it down sufficiently, it answers best to take out the capillary thread when thi lubrication I ni * ■I ' if 84 LTTPULINE. is not required ' and to effect this easilj, I have a tin top to the cup, with a round pipe soldered to it : this pipe has a slit in it, like a pencil case, and allows a bolt b, to slide easily in it. In Jig. 881, the bolt is down ; in ^g. 882, the bolt, which is a piece of brass wire, is drawn up, and there is no capillary action between the thread and the oil. In Jig. 882, it will be observed, that the bolt is kept in its place by its head c, resting in a lateral slit in the pipe, and it cannot be drawn out on account of the pin E. One end of the thread is fastened to the eye hole at the bottom of the bolt, and the other end is tied to a small wire which crosses the lower orifice of the tube at D, and which is shown in ^l&njig. 883. By this simple contrivance the capillary action can be stopped or renewed in a second, without removing the top of the lubricator. The saving by this plan, instead of pouring oil into the bearings, is 2 gallons out of 8, while the bearings are better oiled. 819 877 878 876 K c, 882 ] E^ " I send you the drawings of the lubricators, with a detailed explanation. I have omitted to state, that the saving in labor is considerable where there are many joints to keep oiled three or four times a day ; and that the workman does not with this apparatus, run the risk of being caught by the machinery. Perhaps your friends may be at a loss how to tie on the cotton or worsted thread. I pass a long thread through the eye-hole e of the bolt, and then draw the two ends through the tube by a fine wire with a hook to it, one end on one side of the cross wire d, and the other end on the othei side. I then put the cover on, and the bolt in the position sho-vn in Jig. 651 ; when by drawing the two ends of the thread, and tying them across the wire d, you have the exact length required. When you wish to see the quantity of oil remaining in the lubricator, the bolt must be dropped as in Jig. 650, and you can then lift the cover a little way oflT, without breaking the thread, and replenish with oil. The cost of Jig. 650, in tin plate, is 9i. The figures in the wood cuts are one third of the full size. « Believe me to be yours sincerely, " E. J. W00LSEY.»» LUPININE, is a substance of a gummy appearance, so named by M. Cussola, because it was obtained from Lupines. LUPULINE, from Humulua Lupulus ; is the peculiar bitter aromatic principle of the hop. See Beeh. MACERATION. LUTE (from lutum, clay; Lut, Fr. ; Kitte, Beschldge, Germ.), is a pasty or loamy matter employed to close the joints of chemical apparatus, or to coat their surfacei and protect them from the direct action of flame. Lutes differ according to the nature of the vapors which they are destined to confine, and the degree of heat which thev are to be exposed to. ^ 1. Lute of linseed meal, made into a soft plastic dough with water, and immediately applied pretty thick to junctions of glass or stone ware, makes them perfectly tight hardens speedily, resists acid and ammoniacal vapors, as also a moderate degree of heat It becomes stronger when the meal is kneaded with milk, lime-water, or solu- tion of glue. 2. Lute of thick gum-water, kneaded with clay, and iron filings, serves well for per- manent junctions, as it becomes extremely solid. 3. By softening in water a piece of thick brown paper, kneading it first with rye- flour paste, and then with some potter's clay, till it acquire the proper consistenc^ a lute 18 formed which does not readily crack or scale off. 4. Lute, consisting of a strong solution of glue kneaded into a dough with new slaked lime, is a powerful cement, and with the addition of white of egg forms the liUe d'ane;—& composition adapted to mend broken vessels of porcelain and stone- ware. 6. Skim-milk cheese, boiled for some time in water, and then triturated into paste with fresh-slaked lime, forms also a good lute. 6. Calcined gypsum, diffused through milk, solution of glue or starch, is a valuable lute in many cases. 7. A lute made with linseed, melted caoutchouc, and pipe-clay, incorporated into a smooth dough, may be kept long soft, when covered in a cellar, and serves admi- rably to confine acid vapors. As it does not harden, it may therefore be applied and taken off as often as we please. 8. Caoutchouc itself after being melted in a spoon, may be advantageously used for securing joints against chlorine and acid vapors, in emergencies when nothing else would be effectual It bears the heat at which sulphuric acid boils. 9. The best lute for joining crucibles inverted in each other, is a dough made with a mixture of fresh fire-clay and ground fire-bricks, worked with water. That cement, if made with solution of borax, answers still better, upon some occasions, as it becomes a compact vitreous mass in the fire. See Cements. Lute /or conjining acids. 1 part of caoutchouc dissolved in two parts of hot linseed- oil, and worked up with pipe clay (3 parts) into a plastic mass. Linseed meal and water forms the best lute for fluo-silicic acid. LUTEOLINE, is a yellow coloring matter discovered by Chevreul in weld. When sublimed, it crystallizes in needles, LYCOPODIUM CLAVATUM. The seeds of the lycopodiura ripen in September They are employed, on account of their great combustibility, in theatres, to imitate the sudden flash of lightning, by throwing a quantity of them from a powder puff or bellows, across the flame of a candle. ' LYDIAN STONE, is flint-slate. M. MACARONI, is a dough of fine wheat flour, made into a tubular or pipe form of the thickness of goose-quills, which was first prepared in Italy, and introduced into commerce under the name of Italian or Genoese paste. The wheat for this purpose must be ground into a coarse flour, called gruau or semoule, by the French, by means of a pair of light mill-stones, placed at a somewhat greater distance than usual. This temoule is the substance employed for making the dough. For the mode of manufac- turing it into pipes, see Vermicelli. mace; is a somewhat thick, tough, unctuous membrane, reticulated or chapt, of a yellowish-brown or orange color. It forms the envelope of the shell of the fruit of the mi/rishca mosckata, which contains the nutmeg. It is dried in the sun, after being dipped in brine ; sometimes it is sprinkled over with a little brine, before packing to prevent the risk of moulding. Mace has a more agreeable flavor than nutmeg • with a warm and pungent taste. It contains two kinds of oU ; the one of which is unctuous, bland, and of the consistence of butter ; the other is volatile, aromatic, and thinner. 1 he membrane is used as a condiment in cookery, and the aromatic oil in medicine. The quantity imported in 1850 was 77,337 lbs.; in 1851, 74,863 lbs. ; entered for consumption, 1850, 21,997 lbs.; 1851, 21,695 lbs.; duty received, respectively, 2.887i and 2,847 «. -' r jt * MACERATION (Eng. and Fr. Einwichen, Germ.), is a preparatory steep to / 86 MACHINES (SELF-ACTING). MADDER. 87 »iii which certain vegetable and animal substances are submitted, with the view of dis- tending their fibres or iwres, and causing thorn to he penetrated by such menstruiias are best adapted to extract their soluble parts. Water, alone, or mixed with acids, alkalis, or salts; alcohol and ether, are the liquids usually employed for that purpose. MACHINES {Self-acting.) The application of aclf -acting Machines to the Construc- tion of Machinery. It is nearly half a century since I first became acquainted with the engineering profession, and: at that time the greater part of our mechanical opera- tions were done by hand. On my first entrance into Manchester there were no self- acting tools, and the whole stock of an engineering or machine establishment might be summed up in a few ill-constructed lathes, a few drills, and boring machines of rude construction. Now compare any of the present works with what they were in those days, and you will find a revolution of so extraordinary a character, as to appear to those unacquainted with the subject as scarcely entitled to credit. The change thus effected, and the improvements introduced into our constructive machinery, are of the hi'^'hest importance ; and it gives me pleasure to add that they chiefly belong to Manchester, are of Manchester growth, and from Manchester they have had their origin. It may be interesting to know something of the art of tool-making, and of the discoveries anil progress of machines which have contributed so largely to multiply the manufactures as well as the construction of other machines employed in practical mechanics. In Manchester the art of calico-printing was in its infancy forty yeare ago; the flat press, and one or at the most two colored machines, were all that were then in use; the number of those machines is now greatly multiplied, and some of them are capable of printing eight colors at once; and the arts of bleaching, dyeing, and finishing, have undergone equal extension and improvement. In the manufacture of steam-engines there were only three or four establishments that could make them, and those were Jiolton and Watt, of Soho ; Fenton, Murray and Wood, of Leeds, and Messrs. Sherratts ot this town. The engines of that day ranged from 3 to 60 or at the most 70 horses' power; now they are made as high as 500, or in pairs from 1,000 to 1,200 horse. An order for a single engine at that time was considered a great work, and frequently took ten or twelve months to execute ; now they are made by dozens, and that with a degree of despatch as to render it no unccftnmon occurrence to see five or six engines of considerable power leave a single establishment in a month. In machine making the same powers of production are apparent. In this department we find the same aeti vitj^ the same certainty of action, and greatly increased production in the manufacture of the smaller machines, than can possibly be attained in the larger and heavier description of work. The self-acting, turning, planing, groovinsr, and slotting machines have afforded 80 much accuracy and facility for construction, as to enable the mechanical practitioner to turn, bor^and shape with a degree of certainty almost amounting to mathematical precision. The mechanical operations of the present dav could not have been accom- plished at any cost thirty years ago, and what was considered impossible at that time IS now performed with a degree of intelligence and exactitude that never fail to accom- plish the end m view, and reduce the most obdurate mass to the required consistency, m all those forms so strikingly exemplified in the workshops of engineers and machinists, lo the intelligent and observant stranger who visits these establishments, the first thing that strikes his attention is, the mechanism of the self-acting tools, the ease with which they cut the hardest iron and steel, and the mathematical accuracy with which all the parts of a machine are brought into shape. When these implements are carefully examined it ceases to be a wonder that our steam-engines and machines are so beau- tifully and correctly executed. We perceive the most curious and ingenious contri- vances adapted to every purpose, and machinery which only requires the attendance of a boy to supply the material and apply the power, which is always at hand. In conclu- sion, 1 would observe that it is an honor to this country, that we stand at the head of the engineering and mechanical profession. It is an art— I would call it a science— which has occupied the attention of the greatest men from the days of Galileo and New- ton down to those of Watt and Sraeaton, and it now receives attentive consideration from some of the ablest and most distinguished men of the present time. And of the^e ™^y *WM^?^® Poncelet, Morni, Humboldt, Brewster, Babbage, Dr. Robinson (of Ar- magh), Willia and many others, to show the interest that is taken by these great men m the advancement of mechanical science. A great deal has been done, but a great deal more may yet be accomplished, if by suitable instruction we carefully store the mmds of our foremen and operatives with useful knowledge, and afford them those opportunities essential to its acquisition. We must try to unite theory with practice, and bring the philosopher into close contract with the practical mechanic. We must try to remove prejudices, and to encourage a sounder system of management in the manufactures, design, and projects of the useful arts. When this is accomplished, we shall no longer witness abortions in construction, but a carefully well-digested system of operations, founded on the unerring laws of physical truth.— W. Fairhaim Esq MACHINERY for cask-making. A novel method of constructing casks, barrels, and &I1 vessels connected with cooperage, may be seen in operation at the Patent Cooper- age Works in Wenlock Road, City Road. By the emploj'^ment of the steam-engine, the circular saw, and a recently-invented jointing and backing machine, a cask of the largest dimensions can be completely formed and made ready for use in the short space of fave minutes, from the raw material, viz., a piece of oak. The staves of the cask are first cut with straight sides, the circular saw being placed at a right angle with the oak plank. The stave is then placed horizontally, and bent into a curve by a power- ful machine, and brought into contact with a circular saw on each side of it, placed at an angle. This process gives the proper shape to the stave, the sides being gradually tapered at the ends, and made to bulge in the middle. The jointing and backing ma- chine, the new invention, is also used for this purpose, and is more rapid in its execu- tion than the angular saws ; it in fact works with the most marvellous rapidity and precision. The staves and one end of the cask are then placed in a machine formed of iron rods, called a trussing machine ; each rod acts upon a separate stave, and the whole of the staves being equally compressed into a circle, the hoops are placed around them, and the cask is complete. The neatness and finish of the work are equal to what a good cabinet-maker can produce, every part being true and accurate. The calcula- tion is, that 15 workmen, with the use of this machine, can make 150 casks a day; whereas the same number of persons, using only manual labor, could scarcely produce a seventh part of that number. The importance of the invention and the application of steam power to it, may be imagined from the fact that the great brewing firms of the metropolis alone expend many thousand pounds annually in cooperage, that the expenditure of the Navy is still greater, and that the demand of the vintages of the continent is so great that a great deal of wine is lost from the difficulty of furnishing vessels to hold it. The process of this invention will repay the time of a visit to the works. MACLE, is the name of certain diagonal black spots in minerals, like the ace of dia- monds in cards, supposed to proceed from some disturbance of the particles in the act of crystallization. MADDER {Garatiee, Fr.; Faberrbthe, Germ.), a substance very extensively used in dyeing, is the root of the Jiubia tinctorum, a plant of which two species are distin- guished by Linnaeus. The best roots are those which have the size of a writing quill, or, at most, of the little finger. They are semi-transparent, and reddish; have a strong odor, and a smooth bark. They should be of two or three years' growth. The madder, taken from the ground and picked, must be dried in order to be ground and preserved! In warm climates it is dried in the open air ; but elsewhere stoves must be employed. The stringy falaments and epidermis are to be removed, called mulle ; as also the pith, so as to leave nothing but the ligneous fibres. The prepaiation of madders is carried on in the department of the Rhone, in the fol- lowing manner. The roots are dried in a stove heated by means of a furnace, from which the air is allowed to issue only at intervals, at the moment when it is judged to be saturated with moisture. The farnace-flue occupies a great portion of the floor ; above are three close gratings, on which the roots are distributed in layers of about two decimetres (nearly 8 inches). At the end of 24 hours, those which are on the if MADDER. mon madder ; and what issues at the extremity of the bolter is called the flour. Last.r. wT, ^liTi, r''"' '^r°'iS ^^^ ^^'"' »^^ ^^^'^'^'^ i" ^ '"iU with vertical stones, and what^goes thrJuI^^ '''""' "'"' '^''- ^^^'^ "'^^^^ "^^"^ ^^ ^^^^^^ ^^"^^ ^^^^ The madder of Alsace is reduced to a very fine powder, and its coloring matter is ex- tracted by a much longer ebulUtion than is necessary for the lizari of the Levant The prepared madders ought to be carefully preser^-ed from humidity, because they easily im- bibe moisture, m which case fermentation spoils their color. ^ ^ D Ambourney and Beckman have asserted, that it is more advantageous to employ the fresh root of madder than what has been submitted to desiccation, cspeciaSy by means ^stoves. But m its states of freshness, its volume becomes troublesome in the dTei^' bath and uniform observation seems to prove that it ameliorates by age. Besides il must be rendered suceptible of keeping and carn'ing easily. -oesiaes, ii It appears that madder may be considered as composed of two coloring substances one w^r ;i r ^"^ ^'''^''P^ ^'^^ ^^' "^^^^ '' ^^- ^«t^ «^ '^^'^ substances may comWne witn tne stutt. it is of consequence, however, to fix only the red part. The dun nortion appears to be more soluble, but its fixity on stuffs may possibly be increased by the affinTty which It has for the red portion. ^ amuujr The different additions made to madder, and the multiplied processes to which it is sometimes exposed, have probably this separation for their chief object. The red portion of madder is soluble, but in small quantity, in water. Hence but a imited concentration can be given to its solution. If the portion of this substance bS ^ much increased, so far from obtaining a greater effect, we merely augment the pro! portion of the dun part, which is the more soluble of the two ^ I«J2 5°"^^^"^"=^ o^* the Societe Industrielle of Mulhausen having offered in the year 1826 large premiums to the authors of the best analytical investigation of madder ei^ht memoirs were transmitted to it m the year 1827. They were examined with the c^'eaies care by a committee consisting of able scientific and practical men. None of th^ com petitors however fulfi led the conditions of the programme issued by the societ^-; but four of them received a tribute of esteem and gratitude from it ; MM. Robiquet and Coin at Pars,Kuhmann at LiHe, and Houton-Libillardiere. Fresh premiums were offer«l for next year, to the amount of 2000 francs. ""t^reu lor t. Jlf^ ""^f discover^' made concerning this precious root, would be of vast consequence to dyers and calico-printers. Both M. Kuhlmann, and Robiquet and Colin, conceIvS that they had discovered a new principle in madder, to which thev gave the na^ ahzaruu:. The latter two chemists treated the powdered madder wit'h sulphuric acTd ^mg care to let it heat as little as possible. By this action the whole is carbonLed except perhaps the red matter. The charcoal thus obtained is pulverized mked wfth Tm^'^J^r'' ^Z^ "" ^J^'^r^ ^'^ ^^^^^ i'^ '^' *=°ld- l' ^^ next S/g?ound,Tnd diffused through fifty parts of water, containing six parts.of alum. This mkmre^s then boiled for one quarter of an hour, and thrown upon a filter cloth whUe boS^J hot The residuum is once more treated with a little warm alum water. The two liquo^*are to be mLxed and one part of sulphuric acid poured into them; when thlj are XwS o cool with occasional agitation. Flocks now make their appearance the clear Cm i^ decanted and the grounds are thrown upon a filter. The^pr^rpUate is to be washei IS obtamed in a red or purple state. This purple substance, when heated dr,^ give *out mre"Tem"ns'' ^"^^^^""^^^^^ «^' ^^^^^ ^^ ^^^^ of animal mattei ; whOraXcoaU; M. Dan. Koechlin, the jusUy celebrated caUco-printer of Mulhausen, has no faith in ft^ouTnnt h.' ^^r^ T'^'^Pi" "^ "^^^^'^ ' "^^ ^^^^« "^o^^over that, Vere ?t of value" wo,?lH 1 t r "-" [^^*^4 o'^ the great scale, on account of the destructive heat whS would result from the acd acting upon a considerable body of the ground madder Their o e'sTft^?"' %""'^S'^ substance, as it ought to be, if approximate prin^rpleT for sam' tZ A °^*^^^tl" ^"^^'^^^ repetitions of the process have produced very variable S- Iffo H hn ^'"'"^-r J^' '"^^^r' ^.^ ^^^^"^"' ^^«^?»^ ri^l^^^ i"^ *^olor than those of Alsace afford however httle or no ahzarine. In fact, jncrpuHne, the crude substance from whfch they profess to extract alizarine, is a richer dye than this;mre substance itseff Madder contains so beautiful and so fast a color, that it has become of almost universal emplc^ment in dyeing; but that color is accompanied with Tmany oTheJ substances which mask and degrade it, that it can be brought out and fixed 3y after a orby'thTrcrofris'th"' ''"''"'^- "^f. P--^-- This dye isbesidei^^mti: k ;Jrt • ^ *^^^ thrown away in the dye-house ; the portion supnosed to he exhausted being often as rich as other fresh madder ; henc^ it would be Tmost valuable Before the time of Haussmann, an apothecary at Colmar, the madder bath was subject I* 2 MADDER. 89 to many risks, which that skilful chemist taught dyers how to guard against, by intro- ducing a certain quantity of chalk into the bath. A change of residence led Haussman to this fortufate result. After having made very fine reds at Rouen, he encountered the greatest obstacles in dyeing the same reds at Logelbach near Colmar, where he went to live. Numerous trials, undertaken with the view of obtaining the same success in his new establishment, proved that the cause of his favorable results at Rouen existed in the water, which contained carbonate of lime in solution, whilst the water of Logelbach was nearly pure. He then tried a factitious calcareous water, by adding chalk to his dye bath. Haying obtained the most satisfactory results, he was not long of producing here as beautiful and as solid reds as he had done at Rouen. This practice became soon general among the calico-printers of Alsace, though in many dve-works the chalk is now replaced by lime, potash, or soda. But when the madder of Avignon is used, all these antacid correctives become unnecessary-, because it contains a sufficient quantity of carbonate of lime ; an important fact first analytically demonstrated by that accurate chemist M. Henri Schlumberger of Mulhausen. Avignon madder indicates the pre- sence of carbonate of Ume in it, by effervescing with dilute acids, which Alsace madder does not. M. Kuhlman found a free acid resembling the malic, in his analysis of madders But his experiments were confined to those of Alsace. The madders of Avignon are "on the contrary alkaline, as may be inferred from the violet tint of the froth of their infusions • whereas that of the Alsace madders is yellowish, and it strongly reddens litmus paperl This important difference between the plants of these two districts, depends entirely upon the soil ; for madders grown in a calcareous shelly soil in Alsace, have been found to be possessed of the properties of the Avignon madder. The useful action of the carbonate and the phosphate of lime in the madder of Avio-non, explains why madders treated with acids which remove their calcareous salts, without taking away their coloring matter, lose the property of forming fast dyes. Many manu- facturers are in the habit of mixing together, and with advantage, different sorts of mad- jj r^ , Avignon contains so much calcareous matter that, when mixed with the madder of Alsace, it can compensate for its deficiency. Some of the latter is so deficient as to afford colors nearly as fugitive as those of Brazil wood and quercitron. The Alsace inadders by the addition of chalk to their baths, become as fit for dyein? Turkey reds as those of Avignon. When the water is verj- pure, one part of chalk ought to be used to hve or Alsace madder, but when the waters are calcareous, the chalk should be omitted. Lime, the neutral phosphate of lime, the carbonate of magnesia, oxvde and carbonate of rmc, and several other substances, have the property of causing madder to form a fast dye, m like manner as the carbonate of lime. The teniperature of from 50° to 60° R. (145° to 167° F.), is the best adapted to the solution of the coloring matter, and to its combination with the mordants ; and thus a boiling heat may be replaced advantageously by the long continuance of a lower tempera- ture. A large excess of the dye-stuff in the bath is unfavorable in two points of view • It causes a waste of coloring matter, and renders the tint dull. It is injurious to allow the bath to cool, and to heat it again. In a memoir pubHshed by the Society of Mulhausen, in September, 1835 some interesting experiments upon the growth of madders in factitious soils are related by MM. KoBchlin, Persoz, and Schlumberger. A patch of ground was prepared contain- ing from 50 to 80 per cent, of chalky matter, and nearly one fifth of its bulk of good horse-dung. Slips of Alsace and Avignon madders were planted in March 1834 and a part of the roots were reaped in November following. These roots, thou'^h of only six months growth, produced tolerably fast dyes, nor was any diflerence observable between Ihe Alsace and the Avignon species; whilst similar slips or cuttings, planted in a natural non-calcareous soil, alongside of the others, yielded roots which' gave fugitive dyes. ^ — o • — " — ~ ~7 J -^—^.^ M.-^^t^%,^ TT AixvAt «£Ci V c X Ui^lllV c lives others were planted in the soU of Palud, transported from Avignon, which contained more than 90 per cent, of carbonate of lime, and they produced roots that gave still faster dyes than the preceding. Three years are requisite to give the full calcareous impregna- tion to the indigenous madders of Avignon. As to the function of the chalk, valuable observations, made long ago by M Daniel Koechlin, have convinced him, that the combination of two different bases with a coloring matter, gave much more solidity to the dye, in consequence, undoubtedly, of a greater insolubility m the compound. Experiments recently made by him and his collea^-ues above named, prove that in all cases of madder dyeing under the influence of chalk a certain quantity of lime becomes added to the aluminous mordant. In the subseuue'nt clearing with a soap bath, some of the alumine is removed, and. there remains upon the libre of the cloth a combination of these two earths in atomic proportions. Thus the chalk is not for the purpose of saturating the acid, as had been supposed, but of forming a definite compound with alumina, and probably also with the fatty bodies, and the color- ing matter itself. / |!| 1 ■ 90 MADDER. The red mordants are prepared commonly in ALsace, as follows : — The crushed alum and acetate of lead being weighed, the former is put into a deep tub, and dissolved by adding a proper quantity of hot water, when about one tenth of its weight of soda crystals is introduced to saturate the excess of acid in the alum. The acetate of lead is now mix- ed in ; and as this salt dissolves very quickly, the reaction takes place almost instantly. Care must be taken to stir for an hour. The vessel should not be covered, lest its con- tents should cool too slowly. The different mordants most generally employed for madder, are detailed under Colors. in Calico-Pkinting and Mordant. Much mordant should not be prepared at once, for sooner or later it will deposite some sub-acetate of alumina. This decomposition takes place even in corked vials in the cold • and the precipitate does not readily dissolve again in acetic acid. All practical men know that certain aluminous mordants are decomposed by heating them, and restored on coolin*' as Gay Lussac has pointed out. He observed, that by adding to pure acetate of alumina' some alum or sulphate of potash, the mixture acquires the property of forming a precipi- tate with a heat approaching the boiling point, and of re-dissolving on cooling. The pre- cipitate is alumina nearly pure, according to M. Gay Lussac ; but^ by M. Koechlin's more recent researches, it is shown to be sub-sulphate of alumina, containing eight times as much base as the neutral sulphate. Madder dye. — On account of the feeble solubility of its coloring matter in water, we cannot dye with its decoction ; but we must boil the dye-stuff along with the goods to be dyed ; whereby the water dissolves fresh portions of the dye, and imparts it in succession to the textile fibres. In dyeing with madder, we must endeavor to fix as little of the dun matter as possible upon the cloth. Dyeing on woo/.— Alumed wool takes, in the madder bath, a red color, which is not so bright as cochineal red, but it is faster ; and as it is far cheaper, it is much used in England to dye soldiers' cloth. A mordant of alum and tartar is employed ; the bath of madder, at the rate of from 8 to 16 ounces for the pound of cloth, is heated to such a de- gree that we can just hold our hand in it, and the goods are then dyed by the wince, with- out heating the bath more till the coloring matter be fixed. Vitalis prescribes as a mor- dant, one fourth of alum, and one sixteenth of tartar; and for dyeing, one third of madder, with the addition of a 24th of solution of tin diluted with its weight of water. He raises the temperature in the space of an hour to 200°, and afterwards he boils for 3 or 4 min- utes ; a circumstance which is believed to contribute to the fixation of the color. The bath, after dyeing, appears much loaded with yellow matter, because this bar less affinity for the alum mordant than the red. Sometimes a little archil is added to the madder, to give the dye a pink tinge ; but this is fugitive. Silk is seldom dyed with madder, because cochineal affor'.s brighter tints. Dyeing wi cotton atid linen, — The most brilliant and fastest madder red is the Turkey oi Adrianople. The common madder reds are given in the following way : — The yarn or cloth is boiled in a weak alkaline bath, washed, dried, and galled, by steeping the cotton in a decoction of bruised galls or of sumach. Afler drying, it is twice alumed ; for which purpose, for every 4 parts of the goods, one part of alum is taken, mixed with l-16th of its weight of chalk. The goods are dipped into a warm solution of the alum, wrung out, dried, and alumed afresh, with half the quantity. The acetate of alumina mordant, de- scribed above, answers much better than common alum for cotton. After the goods are dried and rinsed, they are passed through the dye-bath, which is formed of | lb. of good madder for every pound of cotton ; and it is raised to the boiling point by degrees, in the space of 50 or 60 minutes. Whenever the ebullition has continued a few minutes, the goods must be removed, washed slightly, and dyed a second time in the same way, with as much madder. They are then washed and passed through a warm soap bath, which removes the dun coloring matter. Holterhoff prescribes for ordinary madder red the following proportions : — 20 pounds of cotton yarn ; 14 pounds of Dutch madder; 3 pounds of nut-galls ; 5 pounds of alum ; to which I lb. of acetate of lead has been first added, and then s quarter of a pound of chalk. In the calico-print works the madder goods are passed through a bran bath first, im- mediately after dj eing ; next, after several days exposure to the air, when the dun dye has become oxydized, and is more easily removed. An addition of chalk, on the principles explained above, is sometimes useful in the madder bath. If bran be added to the madder bath, the color becomes much lighter, and of an agreeable shade. Sometimes bran-water is added to the madder bath, instead of bran. Mrianople o?" Turkey red. — This is the most complicated and tedious operation in the art of dyeing ; but it produces the fastest color which is known. This dye was discover- ed in India, and remained long a process peculiar to that country. It was afterwards practised in other parts of Asia and in Greece. In 1747, Ferquet and Goudard brought Greek dyers into France, and mounted near Rouen, and in Languedoc, Turkey-red MADDER M dye works. In 1765, the French government, convinced of the importance of this business, caused the processes to be published. In 1808, Reber, at Mariakirch, furnish- ed the finest yarn of this dye, and M. Kochlin became celebrated for his Turkey-red cloth. Process for Turkey. red. —The first step consists in clearing the yarn or cloth in alka- line baths, and dipping them in oily liquors, to which sheep's dung was formerly added. This operation is repeated several times, the goods being dried after each immersion. There next follows the cleansing with alkaline liquors to remove the excess of oil, the gallinsr, the aluming, the maddering, the brightening or removing the dun part of the dye by boiling, at a high temperature, with alkaline liquid, and the rosing by boiling in a bath of salt of tin. We shall give some details concerning this tedious manipulation, and the differences which exist in it in the principal dye-works. At Rouen, where the process was first brought to perfection, two methods are pursued, called the gray and the yellow course or march. In the gray, the dye is given immediately after the cotton has received the ofty mordant, the gall, and the alum, as it has then a gray color. In the yellow course, if is passed through fresh oils, alum, and galls before the maddering, the cotton having then a yellow tint. Different views have been taken of the principles of the Turkey-red dye, and the ob- ject and utility of the various steps. The most ancient notion is that of animalizing the cotton by dung and blood, but experience has proved that without any animal matter the finest color may be obtained. According to Dingier, the cotton is imbued with oil by steepi.ig it in combinations of oil and soda ; the oil is altered by repeated dryings at a high temperature ; it attracts oxygen from the air, and thereby combines intimately with the cotton fibre, so as to increase the weight of the stuff. The dung, by a kind of fermenta- tion, accelerates the oxydizement, and hence crude oil is preferable to pure. In England, the mucilaginous oils of Gallipoli are preferred, and in Malabar, oils more or less rancid. The drying oils do not answer. The subsequent treatment with the alkaline liquors removes the excess of oil, which has not been oxydized and combined ; a hard drying completely changes that which remains in the fibres ; the aluming which follows combines alumina with the cotton ; the galling tans the fibres, producing a triple com- pound of oil and alum, which fixes the coloring matter. The object of the other steps is obvious. According to Wuttich, the treatment with oil opens the cotton so as to admit the mor- dant and the coloring matter, but the oil and soap do not combine with the fibres. In the alkaline baths which follow, the oil is transfoi-med into soap and removed; whence the cotton should not increase in weight in the galling and aluming ; the cotton suffers a kind of tanning, and the saline parts of the blood assist in fixing the madder dye. The German process improved, according to Dingier, consists of the following opera- tions : mordant of an oily soap or a soapy liniment, hard drying; alkaline bath, drying, steeping, rinsing away of the uncombined mordant, drying ; galling, doing ; alumin**, drymg, sleeping in water containing chalk, rinsing ; madilering, airing, rinsing ; bright- ening with an alkaline boil, and afterwards in a bath containing salt of tin ; then wash- ing and drying. The yarn or the cloth must be first well worked in a bath of sheep's dung and oil, com- pounded as follows :— 25 pounds of sheep's dung are to be bruised in a solution of pure caustic potash of hydrometer strength 3°, and the mixed liquor is to be passed through a sieve. Two pounds of fine oil are now to be poured into 16 pounds of his ley after which 30 pounds of coarse oil are to be added, with adtation for i of an hour' Other 4 pounds of hot ley are to be weU stirred in, till the whole is homogeneous. This proportion of mordant is sufficient for 100 pounds of cotton yarn, for 90 pounds of un- bleached or 100 pounds of bleached cotton goods. The cotton stuff, after being well wrung out, is to be laid in a chest and covered with a lid loaded with weights, in which state It should remain for five days. At the end of 24 hours, the cotton becomes hot with fermentation, gets imbued with the mordant, and the oil becomes rapidly altered. The goods are next exposed freely to the air during the day, and in the evening they are dried in a hot chamber, exposed to a temperature of 158° F., for 6 or 8 hours, which promotes the oxydizement of the oil. The goods are now passed the second time through a soapy-oil mordant similar to the nrst, then dried in the air by day, and in the hot stove by night. The third and fourth oil-soap steeps are given in the same way, but without the dung. The fifth steep is com- posed of a ley at 2°, after which the goods must also be dried. Indeed, from the first to the fourth steep, the cotton stuff should be put each time into a chamber heated tc U5P b. tor 12 or 15 hours, and during 18 hours after the fifth steep. The uncombined oil must, in the next place, be withdrawn by the deeraissaee, which consists in steeping the goods for 6 hours in a very weak alkaUne ley. After rinsing and wringing, they are dried in the air, and then put into the hot stove. / 92 MADDER. ^■^ =1 ii Sl! H I Hi r? H m> The goods are now galled in a bath formed of 36 pounds of Sicilian sumach, boiled for 3 hours in 260 pounds of water, and filtered. The residuum is treated with 190 fresh pounds of water. This decoction is heated with 12 pounds of pounded nut-galls to the boiling point, allowed to cool during the night, and used next morning as hot as the hand can bear ; the goods being well worked through it. They are again dried in the air, and afterwards placed in a stove moderately heated. They are next passed through a tepid alum bath, containing a little chalk ; left afterwards in a heap during the night, dried in the air, and next in the stove. The dry goods are finally passed through hot water con- taining a little chalk, wrung out, rinsed, and then maddered. For dyeing, the copper is filled with water, the fire is kindled, and an ounce and a half of chalk is added for every pound of madder ; a pound and a quarter of madder being taken for every pound of cotton yarn. The goods are now passed throuffh the bath, so that they penetrate to near its bottom. The fire must be so regulated, that the copper will begin to boil in the course of from 2| to 3 hours ; and the Ebullition must be contmued for an hour ; after which the yarn is air«d and rinsed. Cloth should be put into the dye-bath when its temperature is 77" and winced at a heat of from 100° to 122° during the first hour ; at 167° during the second ; and at the boiling point when the third hour begins. It is to be kept boiling for half an hour; so that the maddering lasts four hours. Dingier does not odd sumach or galls to the madder bath, because their effect is destroyed in the subsequent brightening, and he has no faith in the utility of blood. After being dyed, the goods are washed, pressed, and subjected to a soapy alkaline bath at a high heat, in a close boiler, by which the dun parts of the galls and the madder are dissolved away, and the red color remains in all its lustre. This operation is called brightening. It is repeated in a similar liquor, to which some muriate of tin is added for the purpose of enlivening the color and givinff it a rosy tint. Last of all, the goods are rinsed, and dried in the shade. The Elberfeld process consists for 100 lbs. of the following steps :— 1. Cleaning the cotton by boiling it for four hours in a weak alkaline bath, cooling and nnsing. 2. Working it thoroughly four times over in a steep, consisting of 300 pounds of water 15 pounds of potash, 1 pailful of sheep's dung, and 12^ pounds of olive oil, in which it should remain during the night. Next day it is drained for an hour, wrung out and dried. This treatment with the dung steep, and drying, is repeated 3 times. 3. It is now worked in a bath containing 120 quarts of water, 18 pounds of potash, and 6 quarts of ohve oU; then wrung out and dried. This steep is also repeated 4 times. 4. Sleeping for a night in the river is the next process ; a sUght rinsing without wrine- ing, and drying in the air. ^ * 5. Bath made of a warm decoction (100° F.) of sumach and nut-galls, in which th« goods remain during the night ; they are then strongly wrung, and dried in the air. *u- 1. l"™^?^ '^'^^. addition of potash and chalk; wringing; working it well through this bath, where it IS left during the night. =>i o o 7. Draining, and strong rinsing the following day; piling up in a water cistern. 8. Rinsing repeated next day, and steeping in water to remove any excess of alum trom Uie fibres ; the goods continue in the water tUl they are taken to the dyeing-bath. y. Ihe maddering is made with the addition of blood, sumach, and nut-gaUs; the bath IS brought to the boil in 1 hour and |, and kept boUing for half an hour. 10. The yarn is rinsed, dried, boiled from 24 to 36 hours in a covered copper, with an oUy alkahne hquid ; then rinsed twice, laid for two days in clear water, and dried. 11. Finally, the greatest brightness is obtained by boiling for three or four hours in a soap bath, containing muriate of tin ; after which the yarn is rinsed twice over, steened in water, and dried. * * Process 0/ Haussmann—Ue treats cotton twice or 4 times in a solution of aluminated potash, mixed with one thirty-eighth part of Unseed oil. The solution is made by adding caustic potash to alum. He dries and rinses each time, and dries after the last operation He then rinses and proceeds to the madder bath. For the rose color, he takes one pound 01 madder for one pound of cotton ; for carmine red, he takes from 2 to 3 pounds -and for the deepest red, no less than 4 pounds. It is said that the color thus obtained sur- passes lurkeyred. I ^^t fo'T^ r^'^'^'^Jiy^ V^ of Rov^n.-.YxT^\ operation. Scouring with a soda 1^^' "i A ^"^T' ^"^ '^^'"'^ *^^'® '^ ^^^*"y *^^^ ^^« remainder of the whiU prepara- dried ^^^"^^^^^^ of oil and soda with water. It is then washed, wrung out, and In the second operation, he states that from 25 to 30 pounds of sheep's dung are commonly used for 100 pounds of cotton yarn. The dung is first steeped for some days MADDER. 9S in a ley of soda, of 8° to 10° B. This is afterwards diluted with about 500 pints of a weaker ley, and at the same time bruised with the hand in a copper basin whose bottom is pierced with small holes. The liquor is then poured into a vat containing 5 or 6 pounds of fat oil (Gallipoli), and the whole are well mixed. The cotton is washed in this, and the hanks of yarn are then stretched on perches in the open air, and turned from time to time, so as to make it dry equably. After receiving thus a certain degree of de- siccation, it is carried into the drying house, which is heated to 50° Reaumur (144° Fahrenheit), where it loses the remainder of its moisture, which would have prevented it from combining with the other mordants which it is afterwards to receive. What is left of the bath is called avancesy and is added to the following bath. Two or even three dung baths are given to the cotton, when it is wished to have very rich colors. When the cotton has received the dung baths, care must be taken not to leave it lying in heaps for any length of time, lest it should take fire; an accident which has ocl;asionaUy happened. The white bath is prepared by pouring 6 pounds of fat oil into 50 pints of soda water at 1° or sometimes less, according as, by a preliminary trial, the oil requires. This bath ought to be repeated two, three, or even a greater number of times, as more or less body is to be given to the color. To what remains of the white bath, and which is also styled avarices, about 100 pints of soda ley of two or three degrees are added. Through this the cotton is passed as usual. Formeriy it was the practice to give two, or three, or even four oils. Now, two are found to be sufficient. The cotton is steeped for five or six hours in a tepid solution of soda, of 1° at most • It is set to drain, is then sprinkled with water, and at the end of an hour is washed, hank by hank, to purge it entirely from the oil. What remains of the water of degraissac'e serves for the scouring or first operation. ® For 100 pounds of cotton, from 20 to 25 pounds of galls in sorts must be taken, which are bruised and boiled m about 100 pints of water, till they crumble easily between the fingers. The galling may be done at two operations, dividing the above quantity of galls between them, which is thought to give a richer and more uniform color. The aluming of 100 pounds of cotton requires from twenty-five to thirty pounds of pure alum, that is alum entirely free from ferruginous salts. The alum should be dissoU-ed without boiling, in about 100 pints of river or rain water. When the alum is dissolved, there is to be poured in a solution of soda, made with the sixteenth part of the weight of the alum. A second portion of the alkaUne solution must not be poured in till the effervescence caused by the first portion has entirely ceased— and so in succession. The bath of saturated alum being merely tepid, the cotton is passed through It, as m the gall bath, so as to impregnate it well, and it is dried with the preu cautions recommended above. The dyers who gall at two times, alum also twice for like reasons. ' For 25 pounds of cotton, 25 pints of blood are prescribed, and 400 pints of water. Whenever the bath begins to warm, 50 pounds of madder are diffused through the bath ; though sometimes the maddering is given at two operations, by dividing the mad- der into two portions. The brightening bath is prepared always for 100 pounds of cotton, with from four to five pounds of rich oil, sLx pounds of Marseilles white soap, and 600 litres of soda water of 2° B. The rosing is given with solution of tin, mixed with soap water. *u '^^^ Turkey-red dye of Messrs. Monteith and Co., of Glasgow, is celebrated all ovei the world, and merits a brief description here. The calico is taken as it comes from the loom without bleaching, for the natural color of the cotton wool harmonizes well with the dye about to be given ; it is subjected to a fermentative steep for 24 hours, like that preliminary to bleaching, after which it is wash ed at the dash wheel. It is then boiled in a ley, containing about 1 pound of soda crjs- lals tor 12 pounds of cloth. The oiling process now begins. A bath is made with 10 gallons ot Gallipoh oil, 15 gallon measures of sheep's dung not indurated ; 40 gaUons of solution of soda crystals, of 1-06 specific gravity ; 10 gaUons of solution of peSrl-ash of spec. grav. 1-04; and 140 gallons of water; constituting a milk-white, soapy solution of about spec. grav. 1-022. This liquor is put into a large cylindrical vat, and constantly agitated by the rotation of wooden vanes, which are best constructed on the plan of the mashing apparatus of a brewery, but far slighter. This saponaceous compound is let off as wanted by a stopcock into the trough of a padding machine, in order to imbue every fibre of the cloth m its passage. This impregnation is still more fuUy ensured by laying the padded cloth aside in wooden troughs during 16 or 18 days. The sheep's dung has been of late years disused by many Turkey-red dyers, both in England and France, but it is lound to be advantageous in producing the very superior color of the Glasgow estab- lishment. It is supposed, also, to promote the subsequent bleaching during the exposure >?i 94 MADDER. on the green; which is the next process in favorable weather, but in bad weather thi. goods are dried over a hot-flue. ' weauier the The cloth is padded again with the saponaceous liquor ; and again spread nn tliP .rrncc The cloth by this time is varnished as it were with oil, and must be cleans«i in » npr r,t" "S^?.! ..'•''' "' 'P"='^= ^'^^'y ^-O^' thoroughly diffused throi^ 170 S ons of water. With this saponaceous liquor the cloth is padded as before, and then nass43 9,648 ; 6,872 i 21,735 14,874 8,971 1833. 4,584 3,215 5,904 1,056 7,6(17 5,560 1.040 4,780 6,126 3,503 3,522 Qrs. 93.175 58,497 50,067 40,810 20,716 36,5)70 31,433 25,407 19,899 5,136 15,617 21,115 14,279 7,630 1834. 4,328 3,187 3,139 7,471 1,332 7,546 5,54 1,890 4,540 6,203 3.256 3,870 Qrs. 99,674 74,982 49,105 44,210 26,161 35,438 31,460 29,796 25,009 8,496 18,197 20,835 15,256 8,824 11,429 1,757 8,079 7,602 4,713 4,940 7,094 80 3,520 2,080 1835. Qrs. 106,098 78,087 55,209 49,430 24,376 36,922 33,263 31,525 28,728 10,913 19,213 1S36. 1837. Qrs. 108,715 89,303 53,694 49.831 30,775 42,169 30,859 32,623 28,338 12,657 19,445 23,885 24,971 16,312 J 3,321 1838. 7,618 14,699 2,780 8,790 7,320 4,130 4,964 200 3,268 2,414 3,633 3,330 3,217 3,261 3.545 11,784 115,364 15,369 4,840 9,2.39 7,961 5,255 4,998 6,597 1,516 3,551 3,400 Qrs 100,326 61,440 47.012 42,700 30,623 40,454 32,325 32,347 24,150 16,404 18.842 23,556 1114,023 7,095 15,227 3,4661 3,768 - 3,763 4,046 - 2,201 -I- -J 15,256 6.588 9,286 7,834 6,025 5,042 6,674 2,826 3,174| 2,400 4,552 4,547 4,783 2,665 -1- Qrs. 107,455 90,140 45,460 44,928 35,065 43,444 31,529 31,278 22,486 18,545 20,290 27,320 14,028 7,551 13,012 16,921 10,326 10,723 8,506 6,129 5,888 6,552 3,365 4,058 1,790 6,121 5,039 4,685 1839. 4,599 2,288 Qrs. 114,827 91,069 51,979 44,010 38,466 40.712 31,028 31,008 22,990 19,578 18,688 25,955 12,145 I 5,758 10,610 17,504 11,599 10,456 7,607 6,413 5,256 6,250 4,060 4,.536 5,358 7,030 4,816 3,96 1840. 1841. Qrs. 115,561 98,210 63,622J 48,130 40,767 38,368 30,872 30,310 25,367 20,664 18,328 27,300 18,517 14,630 15,559 11,679 11,532 7,194 6,954 5,152 6,729 4,478 4,964 5,704 Qrs. 106,345 88,132 51,457 47,980 49,797 36,460 30,614 29,450 25,379 22,413 17,840 21,424 16,018 4,400 3,0?^ 5,334 4,443 3,585 4,425 3,001 15,791 13,126 12,111 12,328 7,268 7,175 5,291 5,758 4,944 5,030 5,862 4,819 4,418 3,155 3,^0 3/5^ '?l 1^2. Qrs. 114,090 92,466 52,098 50,120 43,340 40,484 30,660 29,607 27,050 22,022 20,42S 19,430 17,071 16,688 14,546 13,53<; 13,016 7,65t 7,oa« 6,022 5,556 5,503 4,424 4,983 4,831 4,468 3,878 3,676 U54 1 ""5BBBIS Ill I m d 98 MALT. NAME. Ma Leod, B. - Plimmer ... Laxton and Bryan - Draper and Co. Miller and Co. . Keene and Co. Lane and Bowden - Fleming and Co. Clarke, Charles Garney, J. and Co. Stains and Fox Verey, W. and G. - Jones, T. - - Hcrington and "Wells Hill and Kice - Holt and Sons - Cox, John Griffith, P. UflFord and Co. Masterman and Co. Johnson and Co. Wyatt - Turner, R. - - Dickenson, G. - Honeyball, Edward Jenner, li. and II. - Church, J. L. . Blo2<', B. - . M'l^od, J. M. and Co. Satchell and Son Knight . Chadwick, "W. Turner, John - Locke, R. . - Hume, George Collins, W.L. - West, J. H. - Mantell and Son Addison - - . Martin and Co. Allan Hood and Co. - Clarke, W. - Clarke, 8. Bye, W. and H. - Clarke - Rudge - . - Bricheno, Henry Lamont and Co. Filmer and Gooding Wood and Co. Brown, late Hicks - Manvell, Isaac Abbott, E. Cooper, W. - - Saunders West, J. W. - Harris, Robert 1831. Qrs. 1,656 4,048 814 2,285 585 2,910 1,113 2,302 2,146 1,704 98 901 603 1882. Qrs. 2,947 3,020 857 1,332 463 1,748 754 2.279 1,530 1,808 2,608 674 1,018 206 846 187 756 722 646 6,687 1,646 752 691 244 128 719 202 684 1833. Qrs. 4,236 2,941 1,006 2,168 844 837 1,974 717 4,371 1,063 1,830 218 801 269 855 694 1884. Qrs. 5,479 8,508 1,008 2,266 1,140 875 1,963 794 2,446 1.693 208 1,810 8,117 1,906 584 99 986 176 577 840 690 640 259 975 254 824 914 696 841 271 876 719 780 6,782 7,120 856 888 713 924 526 448 179 451 841 793 471 629 752 1885. Qrs. 5,860 4,187 1,006 8,106 1,208 248 2,042 784 2,499 2,120 472 1,877 1886. Qrs. 4,689 5.573 1,249 3,738 1,302 700 2,615 677 422 1,427 441 822 850 668 488 933 747 9,950 657 884 654 199 255 49U 681 888 800 784 968 2,147 709 496 1,266 519 406 757 621 1,872 813 2,018 2,324 781 1,789 2,809 716 1,037 1,103 772 756 1,067 746 2,177 786 620 1,235 527 406 807 619 671 839 793 706 837 853 9,762 9,885 403; 2,085 - 1,089 834 805 654 2,805 199 810 406 1 6571 295 497 1887. Qrs. 4,960 8,583 88 1,330 1,783 1,578 956 1,853 756 2,151 2,221 953 1,914 2,809 1838. Qrs. 4,700 8,167 712 1,025 1,512 888 742 943 820 1,441 898 1,787 1,624 3,749 7.735 7,888 1,911 846 1,991 1,884 1,291 1,847 2,428 1839. 1840. 897 1,010 1,714 925 672 1,006 978 1,481 169 766 651 1,126 598 565! 693, 768 3971 861 821 725 1,060 407 749 650 812 501 649 741 201 884 9,863 8,600 1,298 824 560 815 806 870 681 768 260 983 8,867 6,251 1,291 756 441 370 81 251 466 Qrs. 4,300 3.213 1,658 855 2,826 1,275 1,796 1,848 614 2,072 1,749 1,665 1,638 1,8.35 307 1,861 1,653 1,241 1,789 2,412 1,018 1,020 1,402 856 975 1,148 877 1,476 5.S2 853 760 812 862 594 694 637 649 504 547 846 886 8,699 7,6.38 1,674 1,493 1,851 679 812 434 811 290 405 Qrs. 8,410 783 2,658 1,711 1,167 2,84') 1,964 2,159 1,934 1,908 2,406 1,762 1.879 1,905 1,677 1,093 1,723 1.916 i;201 1,672 2,413 1841. 1,077 1,100 1,055 929 949 1,034 782 1,308 78 775 728 776 791 620 627 723 72 592 694 462 450 433 655 13,475 1,683 1,442 1,450 7.S2 487 603 862 853 447 Qrs. 8,805 1,653 2,579 1,787 1,740 2,646 2,010 2,417 2,124 2.597 2,628 1,826 1,810 1,746 1,697 972 1,628 1,419 1.850 1,892 2,204 1,219 1,092 1,053 955 1,049 1,118 797 1,063 888 820 768 765 718 627 708 &41 638 637 644 506 502 489 449 18,087 1,614 1,484 1,800 770 490 485 471 444 441 Quantity of Malt which paid Duty, and Amount of Duty, in the Years 1842 to 1846. 1842. Qrs. 8,125 8,001 2.797 2,777 2.685 2,445 2,4.32 2,256 2,255 2,211 2,050 1.840 1,808 1,806 1,628 1,583 1,520 1,429 1,860 1,295 1,267 1,264 1,135 1,087 1,067 1,066 1,046 1,026 945 866 846 754 787 708 706 702 660 642 640 624 629 520 510 501 England - Scotland - Ireland - Total - Quantity. Amount of daty. 1 j 1842. 1848. 1844. 1845. 1843. 1848. 1844 1845. Qimrters. 8,654,850 484.778 130,297 Quarters. 8,850,567 446,220 162,886 Quarter*. 8,979,020 478,562 159,655 Quarters. 8,925,871 543,596 218,020 1 8,959.420 625,176 141,156 4,171,417 483,405 176,459 4,810,605 518,442 172,970 4,253,027 588,895 236,196 4,269,926 4,459,673 4,617,247 4,687,487 4,626,761 4,831,811 5,078,118 5,078,118 Quantity of Malt wetted in Public Brewing in the United Kingdom in the undermentioned years. QFARTERS.! QTTABTKBS. - 3,566,300,1850 - - 5,188,617 - 8,701,70711851 (10 months) 4,868,118 - 8,749,1241 QITARTKRS. QUARTERS. 1887 - 4,030,5iM 1840 - - 8,9;^5,272 1843 lass - . 4,040,395 1841 - - 8,678,013 1844 1889 - 4,082,368 1842 - - 8,688,477 1845 MALT. 99 An Account of the Quantities of Malt brewed by the Twelve principal London Porter and Ale Brewers, during the Five Years ending with October, 1842 (from Slater's Brewers Malt List). issa 1889. Barclay e quanUV of Sre t^e^ent ^n tSe sequently, if, from the total weights 100, we deduct that of tW m^cf,^™! ^ \ ??" matter, the remainder must re,?resent the propo^ln of Ic^ublH^^^^ ^^S words, the saccharine value of the malt. This, as we have stated mil kI ?l rste^^riva-^L-rr;- brewer"87lbri'r"b'" YV'!" l"""'' "' ^6 gallins, beooTe* rt^feuSaS o thJ Drewei, 87 lbs. per barrel, which, however merelv mean« fl,nf *u^ ^ ""guH^e oi me ter of malt, if evaporated down to the bulk ofTbar^e' or la^ ^^ ^"""^ ^T"" ^ ^l"*^" lbs. more than a barrel of water As a rule 594 lh,'f? ^1&^^«^^ ^'>^^^ weigh 87 brewers' pounds, or give a barrel otrorthkvinV a Ved^t^^^^^^^ '' There are some doubts as to the effect of retdninrmLlt fn a bTuTsed or now'^^- ^ state for any considerable period prior to mashing. % a few brewed tWs IZZ^ hurtful, though the majority seem to regard it as indifferenT wIT ^%<5eemed practical experiments oi thiLubject, an! find thTt, ^ " ^7 process of mashing is rather improved than otherwise bv exposTnJf h^tf ? TS\\^'^ of the air, as, by this means, it not only attracts moistLeTom the LT^^ ? ' ^'^^-^ thereby more easily commingled with the water in he mashTun b.ttTn^ r""' %"!" gluten seems also oxidized by this exposure • and hpn^fo fi *, P''''^''''' ""^ ^^'^ produced. A three months' e^xpo^ir:Tbrised maH had nofaraflfni: TeitCk" Quantity or quality of the extract in our exneriments li^Txlt "^ f ^^^"^ *^^ ^.plesLod'e of leterminingthe v'SuT'of^KTotd be^to^^l": ^Kt^^^lt V* iiii 104 MALT KILN. ■■1 i a,| iM ii.' and then ascertain the specific gravity of the solution, but, from the circumstances pre- Tiously stated, this cannot be done, as water continues to combine chemically with tha extract until nothing but sugar exists, and this would require many hours' exposure to a regulated temperature ; hence, the process above given is both the most exact and the most expeditious. In mashing, much depends upon the kind or strength of wort required, as well as upon the circumstance whether table beers and strong beers are brewed in the same establishment, or merely strong beers alone. Any wort weighing, in the language of the brewer, less than 16 lbs., is, properly speaking, a table or small beer wort. The wort of the common porter, drunk in this town, or London beer, weighs 20 lbs., and the strongest bottling stout is about 35. Some of the Burton and Scotch ales run, however, as high as 38 lbs. Under Brewing, the means are pointed out by which any given sample of ale or beer may be analyzed so as to determine ex- actly the weight of the wort from which it was brewed. At present, however, we must turn our attention to the wort as existing in, and flowing from, the mash-tun. In a general way, about 10 gallons of water may be taken tor every bushel of malt in the first mash ; and, after well mixing the two together, the whole should be closely cov- ered down for three hours, ere any attempt is made to draw off the wort. It is imma- terial whether the water be added, to the malt, or the malt to the water ; but the tem- perature of this latter is of great importance. In mild or warm weather a heat of 175® Fahr. is sufficient; but, in winter, 180° will be requisite, as the malt then cools down the average heat more than in summer ; in either case, the temperature, after mixing, should not exceed nor fall much short of 170° Fahr. At the expiration of three hours, this wort may be withdrawn into a proper vessel, or under-back, where it must be kept warm. Its specific gravity should be about 1*092, or weigh 33 lbs. per barrel more than water. So soon as the first wort has been withdrawn (and the quantity of which is seldom more than fths of the water employed), another portion of water must be poured upon the malt, in the ratio of about eight gallons to the bushel of malt em- ployed, and of a temperature somewhat higher than the first After standing two hours this is drained away, like the first, when a quantity of boiling water is slowly trickled down upon the grains from an apparatus called a "sparger," until the wor^ which flows away, ceases to possess any appreciable gravity beyond that of water. The worts are then mixed together, in these cases, where table beer is not made, and the whole reduced, by boiling, to the desired gravity of the beer meant to be brewed. "Where table beer, however, is manufacture^ the strong worts are kept apart and the weak ones alone are fermented for this purpose. In both cases, the strong beers are brewed from worts having a technical weight of from 20 to 36 lbs. per barrel. It has long been supposed, that wort, as usually manufactured, consisted chiefly of su^ar, but this is a great error, for there is seldom so much as one-third of all the extract in wort saccharified- The ordinary proportion is, one part of grape-sugar and three of dextrine. MALT KILN {Darre, Germ.) The improved malt kUn of Pistorius is represented, /Ig. 884, in a top view ; jig. 885, in a longitudinal view and section ; and fig, 886, in transverse section, a a are two quadrangular smoke flues, constructed of fire-tiles, or fire-stones, and covered with iron plates, over which a pent-house roof is laid ; the whole bound by the cross-pieces 6 {figs. 885, 886.) These flues are built above a grating c c, which commences at c' ; in front of c' there is a bridge of bricks. Instead of such a brick flue covered with plates, iron pipes may be used, covered with semi-c/lin- irical tiles, to prevent the malt that may happen to fall from being burned, d d are the breast walls of the kiln, 3 feet high, furnished with two apertures shut with iron MANGANESE. 105 dooi-8, through which the malt that drops down may be removed from time to time. CIS a beam of wood lymg on the breast wall, against which the hurdles are laid down slantingly towards the back wall of the kiln; //are two vertical flues left in the substance ot the walls, through which the hot air, discharged by open pipes laid in a subjacent furnace, rises into the space between the pent-house roof and the iron plates, and IS thence allowed to issue through apertures in the sides, g is the discharge flue in the back wall of the kiln lor the air now saturated with moisture; h is the smoke-pipe, from which the smoke passes into the anterior flue a, provided with a slide-plate, fo^ modifym^ the draught; the smoke thence flows off" through a flue fitted also with a damper-plate into the chunney i k is the smoke-pipe of a subsidiary fire, in case no smoke should pass through h. The iron pipes are 1 1 inches in diameter, the kir-flues/, 5 inches, and the smoke-pipe h, 10 inches square ; the brick flues 10 inches wide, and the usual height of bricks. r»,i^«ti;T"r^ 'vf ^" n' G/tt/.W, or mineral pitch. It is a soft glutinous substance, with the smell of pitch. It dissolves m alcohol, but leaves a bituminous residuum ; as also in naptha, and oil of turpentine. It seems to be inspissated petroleum. MANGANESE (Eng. and Fr. ; Mangan, Braumteinmetal, Germ.) is a grayish-white metal, of a fine-grained fracture, very hard, very brittle, with considerable lustre, of spec. grav. 8-013, and requiring for fusion the extreme heat of 160° Wedgewood It should be kept in closely stoppered bottles, under naptha, like potassium, because with contact of air it speedily gets oxydized, and falls into powder. It decomposes water slowly at common temperatures, and rapidly at a red heat. Pure oxyde of manganese can be reduced to the metallic state only in small quantities, by mixing it with lamp black and oil into a dough, and exposing the mixture to the intense heat of a smith's forge, m a luted crucible; which must be shaken occasionally to favor the ag- glomeration of the particles into a button. Thus procured, it contains, however, a little carbon. ' Manganese is susceptible of five degrees of oxvgenation. 1. The protoxydemay he obtained from a solution of the sulphate by precipitation with carbonate of potash, and expelling the carbonic acid from the washed and dried car- bonate, by calcination in a close vessel filled with hydrogen gas, taking care that no air have access during the cooling. It is a pale green powder, which slowly attracts oxygen frorn the air, and becomes brown ; on which account it should be kept in glass tubes, containing hydrogen, and hermetically sealed. It consists of 77-57 metal and 22-43 oxygen. It forms with 24 per cent, of water a white hydrate ; and with acids, saline compounds ; which are white, pmk or amethyst colored. They have a bitter, acerb taste, and afford with hydrogenated sulphuret of ammonia a flesh-red precipitate, but with caustic alkalis, one which soon turns brown-red, and eventually black. 2. The deutoxyde of manganese exists native in the mineral caUed Braunite: but it may be procured either by calcining, at a red heat, the proto-nitrate, or by spontaneous oxydize- ment of the protoxyde m the air. It is black ; when finely pulverized, dark brown, and is convertible, on being heated m acids, into protoxyde, with disengagement of oxygen eas It consists of 69-75 metal, and 30-25 oxygen. It forms, with 10 per ?ent. of wa?er,l U^^rl brown hydrate, which occurs native under the name of Manganite. It dissolves readilv in tartaric and citric acids, but in few others. This oxyde constitutes a bronze ground in calico-printing. ^ "* 3. Peroxyde of manganese; Braunstein, occurs abundantly in nature. It gives out oxygen freely when heated, and becomes an oxydulated deutoxyde. It consists of 63-3fl metal, and 36-64 oxygen. 4. Manganeiic acid forms green-colored salts, but has not hitherto been insulated from the bases. It consists of 53-55 metal, and 46-45 oxygen. 5. Hypermanganesic acid consists of 49-70 metal, and 50-30 oxygen. Ores of manganese.— There are two principal ores of this metal which occur in great masses ; the peroxyde and the hydrated oxyde ; the first of which is frequently found in primitive formations. 1. Metalloide oxyde of manganese ; pyrolusite, or gray manganese ore : has a metallic lustre, a steel gray color, and affords a black powder. Spec. grav. 4-85. Scratches calc- spar. It eff^ervesces briskly with borax at the blow-pipe, in consequence of the disencac'e- ment of oxygen gas. This is the most common ore of manganese, and a very valuable one, being the substance mostly employed in the manufacture of chloride of lime and of flmt-glass. It is the peroxyde. Great quantities are found near Tavistock, in Devon- shire, and Launceston, in Cornwall. 2. Bmunite, is a dark brown substance, of a glassy metallic lustre, affording a brown powder. Spec, grav 4-8. It scratches feldspar ; but is scratched by quartz. Infusible at the blow-pipe, and effervesces but slightly when fused with glass of borax It is the deutoxyde. It gives out at a red heat only 3 per cent, of oxygen. 3. ManganUe, or hydroxyde of manganese j is brownish-black or iron-black, powder 106 MANGANESE. :i mi f^ 1 'I? su^^huy^whenrused with ^^s ^c:ti/:^^zsz72:^'::t^ vesce wl^n fSwi.l'borS I fsTdeuZld'e"'^' t •. • ' ""' ""^"'''P'' ' ""^ ""' '^"- to the arts. "" ""ra^- " is a deutoxyde. ThiS is a rare mineral, and of no value peLfd^iuhlf el^^r""' ^^""' ""''• " '' « ■»»«»'"»" "f -l^'oMe and dark sSTv" W^"vt'95"t "^ "T""''' ' ""^ » "«■""" "'^^ ' " "-><, or aide o7potassiun, K ".iSLr^f s^^pfc-S^^^'^V^^resTeTsr'' """ '"' '■""«^''- flnn'r t'P^r"!; ^^T^''^'. o/r«anga»«,« is brown or black. Spec grav 3 6 scratches nuor; affords by calcination a I'prv liftlp nf on »«m * "i;^^. &i«v. o o , scraicnes oec^utl^alirtitl^^^^^^^^^ P-^'^e of manganese. It massive. Some varietirposserCe^?ect^^^^^^^ The'el'^t' ^' '''''' Sr^^^r^^iS^-bf i^; I- ES^ M ^J^p^^: generally they contained no les thTn 2^%rr/ of^ « o '5' r'^;"* I"'^ ' t'Sa^'T^"' the remainder amountingTo^'ly^o';^/^^^^^^^^^^ 'p^/oxySe "^''' '^'^^^ places the manganese powder in a smSl^'e^rrt^Tr S"u.^re^^^^^^^^^^ thl LinTn^mflk^nf r °^"^'^ T'l; *^^ ^'^ «^ ^ ?^^^1« h^^*' '« Lnsmitted into a^lel co„' 8^ u ifn nf ^ll \^°^^,?^ P«t««h water. This liquor is afterwards poured into a dilute orTfuuifFr «^^?f?«i.«^°^, the quantity of chlorine is inferred from the quaS The ^^n,!?i". "" "^Vfl • '! ^r^^^^'^- I P^s the chlorine into test solution of inSig^ The manufacturer of flint glass uses a small proportion of the black manganese of ^ s'^n^d reltl^'r To'l!^^^^^^^^^ ^'T "" ^p' *'^-- ^-- the^L";rern?Lre tainir.^ I^PA? • -^^ * ^^ of great consequence to get a native manganese con- duTwill il r^'u """"i" ^' P^''^^^^' «^°«« ^^^^«t the color or limpidity^of hTs prS- duct will depend altogether upon that circumstance. ^ ^ ^ ,. X.^^'i^'t^ u^"^^''^.^^ has been of late years introduced into calico printing to^iva ^^Tl'^lt ^V^rr'" impression. It is easily formed by heatinrth" b afk old? ThP Ir ^}'^^\^ ^^"^^ "°*^' ^^*^ sulphuric acid. See Calico pf int^o ^ '''"^^• The peroxide of manganese is used also in the formation of glJs pastes and in malting the black enamel of pottery. See Oxalic Acid. ^ ^ ^'' *'''* "* The recovery of manganese in the state of peroxide for the chemical arts in whioh It IB 80 extensively consumed, has been long a desideratum in manufactured' r.^-, f IT^ pretends to reconvert the Residuum that is left after the disenea^e- nTviiutfnlnUst:?rof^^^^ ^z: 4^-''^^^'^'^' which is pecuHarly fitted, by ?he large ^pr^^o^^ti 'f^oxy^nT^^^^^^^^^ MANGANESE. lOT the purpose of affording either chlorine or oxygen gas again, according to the process It 18 subsequently subjected to. The said residuary matters, after the extrication of the chlorine in the manufacture of chloride of lime, or bleaching powder, and of chlo- rate or hyperoxymuriate of potasli, consist principally of chloride and sulphate of manganese ; but as these residuums may and have been occasionally converted more or less into sulphuret of manganese when they are used to purify coal gas from its sulphur or su phuretted hydrogen, the patentee includes not only the above sulphate and chloride, but also the sulphuret of manganese, among the waste or refuse products, which he converts into a valuable peroxide of that metal. He applies, moreover, this invention to the conversion of all oxides, carbonates, and other combinations of man- ganese whatever, whether native or factitious, which contain the metal in an inferior state of oxidation, into a superoxide of manganese, adapted to produce chlorine by the agency of hydrochloric acid, and oxygen by the agency either of heat alone, or of neat along with sulphuric acid. The manner in which the said invention is to be carried into execution is as follows • The conversion of manganese, whether combined or uncombined from a lower state of oxidation into the higher state of superoxide, is effected by two distinct operations i^irst, It is well known that wh«n peroxide of manganese, called in its purest native state, pyrolu?ite, and also gray manganese ore, is digested with hydrochloric or mu- riatic acid, the oxygen of the metal combines with the hydrogen of the acid to form water, and leave the chlorine of the acid free, while the manganese, thus partially stripped of its oxygen, combines with the rest of the hydrochloric acid to form a mu- riate of manganese. Likewise, when more or less dilute sulphuric acid, common salt (chloride of sodiumX and peroxide of manganese, are so mixed and treated as to be made to react on one another the hydrochloric acid, which is disengaged, is converted by the oxygen of the manganese into water and chlorine, while both the soda pro- duced from the common salt, and the partially deoxidized manganese, combine with the sulphuric acid into sulphate of soda and sulphate of manganese. He converts either the chloride, sulphate, sulphuret, or carbonate, into a sesquioxide or deutoxide of manganese, by one or other of the three following processes :— First, he subjecte dried chloride of manganese to a strong heat, produced either by the united action of burning fuel^ and a jet or jets of an oxy-hydrogen blowpipe, or of a stream of atmos- pheric air thrown upon the burning fuel by a fan or other suitable impulsive power thus forming a kind of blowpipe or blast-furnace, in which the chemical decomposi- tion and reaction are rendered quicker and more complete. The furnace is constructed like an ordinary reverberatory furnace, with the addition of a box or chest of iron open at top, set m the fire-place, close to the bridge, which box is filled with iron turnings, borings, or other small fragments of iron, upon which, in their strongly ig- nited state, water is allowed to trickle or drop down slowly from a pipe, so as as to be deconjposed, and to disengage a stream of hydrogen, which is impelled over the bridge of the furnace upon the hearth by means of a fan or other blowing machine acting at the entrance or door of the fire-place. The manner in which the furnace is regulated 18 as follows:— The fuel, either common coals, coke, anthracite, wood, turf Ac is first lighted upon the grate, and being subjected to the blast of air, soon creates such a temperature as to raise the box of iron turnings to a red-white heat, in which state the water being allowed to trickle down into the said box, is decomposed with the copious disengagement of hydrogen gas. The chloride of manganese may be ex- posed on the hearth of the reverberatory furaace either in a more of less concentrated liquid state, or in a dry state, to the action of the intensely powerful flame, generated as above described, and becomes thereby decomposed by the hydrogen, with the dis engagement of its chlorine in the state of hydrochloric acid or muriatic acid gas whUe ^.nf!;^T'''"r?uPi''*5''''^? "*? manganese becomes at the same time oxidized into the deutoxide. The hydroclonc acid gas disengaged is condensed by means of vaults or large chimneys coritaming wet coke or flint nodules in the w^y often practised m soda manufactories. Instead of the above-described hydrogen flame, heUploys sometimes a simple reverberatory furnace with ordinary fuel, lither with or without blast, m which he resolves the chloride of manganese into hydrochloric acid and per- oxide of manganese, but he prefers the compound flame of hydrogen and ordinary fuel In his second process^ instead of acting on chloride of mangfnese by the flame of combustible matter on the hearth of a furnace, he subjects the chloride ymanga^Le pu into f-%«lay retorts, to an intense heat, by which he expels the chlorine ^Zuy in the state of hydrochloric acid, and partly of chlorine, and the manganese left in th{ retoits ma^ be afterwards peroxidized by l process to be presentiriescXd In his third process he mixes together chloride of manganese anl carbonate of lime, suhr?. tW Z^uir,7:^ equivalent proportions for mutual decomposition, and h^ subjects that mixture to the strong heat of the above-described compound hVdrogeu flame, whereby he obtains a mixture of chloride of calcium (muriate of lime), and o:2de fit 108 MANGANESE. ill! |i' quioxide in a moist state. MANFACTURING INDUSTRY. 109 The third method of converting into peroxide of manganese its lower oxide or car- bonate consists in directing over the surface of either of these, in a moist state, the deutoxide of azote, frequently called nitrous gas, which is obtained as a waste product m certain chemical operations, as in the manufacture of oxalic acid, or nitrate of lead, or of copper, t1v by Wm. Fairbairn Esq. F. R. S., Member of the Institute of France— If we take I will not say a statistical, but a very cursory view of the recent position of Manchester and the surrounding districts, and compare it with what it was at the close of the last and the commencement of the present century, we shall find that at that period the use- fHof fK '""^"f ^'^1 «^*« ^ere comparatively of little importance. We shall also find that the grafts of a new, and above all others an important branch of manufacturino- industry springing into existence. I have no returns of the state of our manufacturing industry at that period, but the writings of one of our eariiest and most intelligent spinners, to whom this country is indebted for many improvements in machinery, Mr. John Kennedy, informs us, that the spinning of cotton yarn antecedent to the year 1768. was of an exceedingly hmited description. That gentleman in his account of the rm / m 111 ■1 i I ! I i I i" 110 MANUFACTURING INDUSTRY. and progress of the cotton trade, stated that the hand-loom as a machine remained stationary for a great number of years without any attempt at improvement until 1750, when Mr. John Kay, of Bolton, first introduced the fly-shuttle, and that the spinning of cotton yarn from that period, and for many years previous, was almost entirely performed by the family of the manufacturer at his own house. This united and simple process went on till it was found necessary to divide their labors, and to separate the weaving from the spinning, and that agam from the carding and other preparatory processes. This division of labor as Mr." Kennedy truly says, led to improvements in the carding and spinning, *'by first introducing simple improvements in the hand instru- ments, with which they performed these operations, till at length they arrived at a ma- chine, which, though rude and ill-constructed, enabled them considerably to increase their produce." Thus it was that improvements, and the division of labor, first led to the factory system, and that splendid and extensive process which at the present mo- ment and for many years to come will affect the destinies of nations. From 1760 to 1770, when Mr. Hargreaves, of Blackburn, first introduced his spinning jenny, (by means of which a young person could work from ten to twenty spindles instead of one), there was little or no change, but a very material alteration took place shortly after the introduction of these improvements, which were immediately followed by Mr. Arkwright's machinery for carding and roving. These accompanied by the introduc- tion of Mr. Crompton's mule, in 1780, may be justly considered to constitute the origin of the factory system, which has now grown to such colossal dimensions, as to render it one of the most important and most extensive systems of manufacture ever known in the history of ancient or modern times. Mr. Arkwright built his first mill at Crom- ford in Derbyshire (I again quote from Mr. Kennedy) " in 1771. It was driven by water, but it was not till 1790, or sometime after, when'the steam engine of Watt came into use, that the cotton trade advanced at such an accelerated speed, as to render its in- crease and present magnitude almost beyond conception. This immense extension ia not only a subject of deep interest to the philosopher and statesman, but one which is likely to furnish a large field of observation for the future historian of his country." I will not trouble you with the statistics of the cotton trade as it now exists, but simply observe, as many of you are doubtless better informed on this subject than my- self, that I am within the mark, when I state that no less than 31,500 bales of cotton are consumed weekly, in the two kingdoms, England and Scotland; that nearly 21,000,000 spindles are almost constantly in motion, spinning upwards of 105,000,000 hanks, or 50,000,000 miles of yarn per day — in length sufficient to circumscribe the globe 2,000 times. Out of this immense production about 131,000,000 pounds of yarn are exported ; the remainder is converted into cloth, lace and other textile fabrics. This marvellous increase, this immense extent of production could not be effected without considerable changes in the prospects of the moral as well as the physical condition of society. It has entirely changed the position of the resident population of the dis- trict ; and the secluded valleys, farm-houses and cottages, the beauties of a Lanca- shire landscape of the last generation, are rapidly giving way to the conversion of villages into populous towns, with innumerable erections which resound with the busy hum of the spindle and the shuttle. Along with these changes we see a new generation springing into existence, factories, steam-engines, and tall chimneys rising in every direction, and the noise and smoke which meet the eye and the ear of the stranger at every step give evidence of the activity and prosperity of the industrious hive, which at some future time in English history will announce to succeeding gene- rations the inventions and the discoveries of the nineteenth century. In this attempt to place before you a short account of the use and progress of our national industry, I must not forget that yarn, however finely or dexterously spun is not cloth ; and here we enter upon another, and equally ingenious process. The yam must be woven before it is fit for use, and we shall be weaving one of the most interest- ing as well as elaborate operations of the useful arts. I need not inform you that the ancient Hindoos, Egyptians, and probably the early Chinese converted their yarn into cloth. The Indian and Oriental department of the Great Exhibition exhibited the mode and primitive character of their looms and other implements, which have been handed down from generation to generation from the earliest periods, without change or im- provement to the present day. Looms of this rude construction were introduced into Europe during the first glimpses of civilization, and for many centuries even the most advanced nations were content to use the same instruments, almost without improve- ment, until the introduction of the flying shuttle and the subsequent invention of Hall and Arkwright opened a new and untrodden field for improvements in every depart- ment of art and manufacture. Power looms at that period were unknown, and although attempts were made by Mr. Cartwright, as early as 1774, to convert the hand loom into a machine to be moved by power, it was not until the beginning of the present cen- tury that the power-loom assumed its present form, and presented that intelligence of MANURE. Ill structure which rendered it self-acting, and enabled it to compete with the hand-loom weaver. From that time (about 1810 or 1812^ we may date the commencement of that increase to which that important branch of our manufacture was extended. The improvements introduced by Mr. Bennet Woodcroft and other for weaving twills and similar fabrics created new expedients and applications, and greatly increased the de- mand of this description of manufactures, whilst the inventions of Jacquard for weav- ing figured cloth startled every one with their extreme ingenuity and beauty, and accom- plished the perfection of machinery for the production of textile fabrics. The increase and extent of cloth manufactured from power-looms may be estimated from official returns, kindly furnished by Mr. Leonard Horner. There are now at work in the United Kingdom above 250,000 power-looms. Now as each loom will upon the aver- age form five to six pieces of cloth per week, each piece 28 yards long, say 25 yards a day per loom, we have 250,000, which multiplied by 25 gives 6,250,000 yards, or 3,551 English miles of cloth per day, the distance between Liverpool and New York. Only think of the importance and extent of a manufacture that employs upwards of 12,000 hands in weaving alone, supplying from that source (the power-loom) an an- nual produce of cloth that would extend over a surface in a direct line of upwards of 1,000,000 miles. But although much has been done, much has yet to be accomplished before the supply equals the demand. It must appear obvious to those who have studied and watched the unwearied invention and continued advancement which has signalized the exertions of our engineering and mechanical industry. But neither difficulties nor danger, however formidable, can stand against the indomitable spirit, skill, and per- severance of the English engineer ; nor will it be denied that the ingenuity and never- failing resources of our mechanical population are not only the sinews of our manu- factures, railways, and steamboats, but the pride and glory of our own country. It is for this important class, that I have ventured to address you, and I trust the time is not far distant, when we shall witness establishments suitable for their educa- tion, such as will teach them to reason and to think, and to impart that knowledge essential to a more correct acquaintance with physical truth, and a clearer conception of the varied manipulations of those arts in which consist the true interests of the country. — Lecture at Manchester. MANURE. A patent for an excellent article of this kind was obtained in May, 1842, by J. B. Lawes, Esq., for a full description of which the reader is referred to the articles Coprolites. He decomposes bones, apatite, and other subphosphates of lime by mixing them in powder with as much sulphuric acid as will liberate enough of the phosphoric to dissolve the phosphate of lime. The free phosphoric acid is thereby ready to combine with the various alkaline earths contained in the soil, while the phosphate of lime is brought to a state of more minute division than is possible by mechanical means. Mr. Lawes also proposes to mix the above soluble superphosphate with such alkalis as are deficient in the soil, and thus to form a manure adapted to fer- tilize it. His third improvement in manure is the formation and application of a liquor of flints, for such soils as are deficient in soluble silica. The last compound he considers to be valuable for grounds much cropped with wheat and other cereals that require a good deal of silica for their growth. It is greatly to be regretted, that this most important subject of scientific research, has hitherto been treated too much in a one-sided manner ; that is, either by individuals little conversant with practical farming, or by farmers little acquainted with the nature of soils, and the changes produced on them by the cultivation of different orders of plants. Under the auspices of the British Association, Professor Liebig, in the year 1840, first promulgated his views on agriculture, from which date we may trace a spirit of investigation into it^ such as had not previously existed in this country. Among other laborers in this field, we must state that Mr. J. B. Lawes, of Rothamstead, in Hertfordshire, was occupied several years prior to the first edition of Professor Liebig's work, in investigating the action of different chemical combinations when applied as manures, to the most important crops of the farm; and having ever since continued his experimental researches with all the lights of science, with which he is familiar, aided by Dr. J. H. Gilbert, a skilful analytical chemist, he has been able to arrive at conclusions of greater value and precision than the merely theoretical determinations of the German professor. In the course of this inquiry, the whole tenor of the resulU of Messrs. Lawes and Gilbert, and also of information derived from intelligent agri- cultural friends, upon every variety of land in Great Britain, has forced upon them opinions different from those of Professor Liebig, on some important points; and more especially, in relation to his so-called " mineral theory," which is embodied in the follow- ing sentence to be found at page 211. of the third edition of his work on Agricultural Chemistry ; where he says " the crops on a field diminish or increase in exact proportion to the diminution or increase of the mineral substances conveyed to it in manure."/ Of the vast importance, both in a scientific and a practical point of view, of correct I II I I M ; tit ' ;i ; it) ; 11 112 MANURE. ideas on the subject here at issue, a judgment may be formed from the manner « which the professor himself speaks of the mineral theory in the new edition of his let- ters on chemistry. Thus at page 482., he says of the agrieulturista of England that sooner or later thejr must see that in the so-called mineral theory in its development and ultimate perfection lies the whole future of agriculture." "Looking upon the subject in a chemical point of view only, it would seem that an analysis of the soil upon which crops were to be experimentally grown, as weU as a knowledge of the composition of the crop should be the first points ascertained, with the view of deciding m what constituents the soil was deficient ; and at the commence- ment of our more systematic course of field experiments, the importance of these points was carefully considered. When we reflect, however, that an acre of soil six inches deep may be computed to weigh about 1,344,000 lbs. (though the roots of plants take a much wider range than this), and taking the one constituent of ammonia or nitrogen as an Illustration, that in adding to this quantity of soil a quantity of amraoniacal salt, containing 100 lbs. of ammonia, which would be an unusually heavy and very effective dressing, we should only increase the per centage of ammonia in the soil by 0-0007 it 18 evident that our methods of analysis would be quite incompetent to appreciate the difference between the soil before and after the application,— that is to say, in its state oi exhaustion, and of highly productive condition, so far as that constituent is con- cerned ; and from our knowledge of the effects of this substance on wheat, we may con- ndently assert that the quantity of it supposed above would have given a produce at least double that of the unmanured land. The same kind of argument might, indeed be adopted m reference to the more important of tliose constituents of a soil which are found m the ashes of the plants grown upon it, and we determined, therefore, to seek our results in another manner. Indeed, the imperfection of our knowledge of the productive quality of a soil, as derived from its per centage composition, has been am- ply proved by the results of analysis which have been published during the last ten years; and in corroboration we need only refer to the opinions of Professor Magurs on this subject, who, in his capacity of chemist to the ' Landes Ockonomie Kollegium' of I'russia, has published the results of many analyses of soils. The truth is, that little is as yet known of what a soil either is, or ought to be, in a chemical point of view • but when we call to mind the investigations of Professor Mulder, in relation to the organic acids found m soils, and of Mr. Way and others, as to the chemical and phy- sical properties of soils, in relation to the atmosphere, and to saline substances exposed to their action in solution, we may at least anticipate for chemistry that she wifi ere long throw important light on this interesting but intricate subject. "In our field experiments, then, we have been satisfied with preserving specimens of the soils which were to be the subjects of them, and have sought to ascertain their deficiency m regard to the production of different crops, by means which we conceive to be not only far more manageable, but in every way more conclusive and satisfac- tory in their result To illustrate,— what is termed a rotation of crops is at least of such universahty in the farming of Great Britain, that any investigation in relation to the agriculture of that country may safely be grounded on the supposition of its adoption. Let us, then, direct attention for a moment to some of the chief features of rotations. What is called a course of rotation is the period of years which includes the circle of all the different crops grown in that rotation or alternation. The crops which thus succeed each other, and constitute a rotation, may be two, three, four or more, varying with the nature of the soil and the judgment of the farmer; but what- ever course be adopted, no individual crop— wheat, for example, is grown immediately succeeding one of the same description, but it is sown again only after some other- crops have been grown, and at such a period of the rotation, indeed, as by experience it is known that the soil will, by direct manure or other means, have recovered its capability of producing a profitable quantity of the crop in question. " On carefully considering these established and well-known facts of agriculture it appeared to us that, by taking soils either at the end of the rotation, or at least' at that period of it when the ordinary course of farming farm-yard manure would be added before any further crop would be grown, we should then have the soils in what may be termed a normal, or, perhaps better still, a practically and agriculturally ex- hausted state. " i/ if "Now, if it is found, in the experience of the farmer, that land of any given quality with w;hich he is well acquainted, will not, when in this condition of practical exhaustion, yield the quantity he usually obtains from it of any particular crop, but that after apply- ing farm-yard manure it will do so, it is evident that if we supply to different plots of this exhausted land the constituents of farm-yard manure both individually and combined, and if by the side of these plots we also grow the crop both without manure of any kind and with farm yard manure, we shall, in the comparative results obtained, have a far more satisfactory solution of the question as to what constituents were, in this ordin- ary course of agriculture, most in defect in respect to the proportion of the particular MANURE. 118 crop experinaented upon than any analysis of the soil could have given us. In other words, we should have before us very ^ood ground for deciding to which of the con- etituents of the farm-yard manure the increased produce was mainly due ou the plat provided with It, in the case of the particular crops ; not so, however, unless the soil had been so far exhausted by previous cropping as to be considered »rac^Jca//y unfit for the growth of the crop without manure. W^e lay particular stress on this point, because we believe that the vast discrepancy in the results of comparative trials with different manures, by different experiments, arise more from irregularity in what may be called the/oa tngr capital of the soil than from irregularities in the original character of the Ipplicadon"" ^""^ ''*'^^ '"'^^*' ^^ '"''^"'^^ *^^ frequent faulty methods of Ji l^ '^ 1^°' ^y ^^i8 fy"'^^*^' rather than by the analytic method that we have sought our results ; and m the carrrying out of our object we have taken wheat as the type of the cereal crops, turnips h» the type of the root crops, and beans as the representa- «pllf $ / ^'^'Z*^^;"* corn crop most frequently entering into rotation ; and having selected for each of these a field which, agriculturally considered, was exhausted, wl have grown the same description of crop upon the same land, year after year, with dif- ferent chemical manures, and in each case with one plot or more continuouslv unma- nured, and one supplied every year with a fair quantity of farm-yard manure. In this way 14 acres have been devoted to the continuous growth of wheat since 1843 8 acres to continuous growth of turnips from the same date, and, 6 to 6 acres to that'of leguminous corn crops since 1846. And of field experiments, beside these which amount in each year to from 30 to 40 on wheat, upwards of 90 on turnips, and 20 to 80 on beans^ others have been made, viz., some on the growth of clover, and some in rela- tion to the chemical circumstances involved in an actual course of rotation, compriainir turnips, barley, clover, and wheat, grown in the order in which they are here itateA It may be stated, too, that m addition to these experiments on wheat, and the other erops usually grown upon the farm, as above referred to, we have for several years been much occupied also with the subject of the feeding of animals, viz. bullocks, sheep, and pigs,— as wel as m investigating the functional actions of the growing plant in rela- tion to the soil and atmosphere ; and in connection with each of theee subjects much laboratory labor has constantly been in progress. a ri^^u «««Pe and object of our investigation has been therefore to examine in the Held, the feeding shed, and the laboratory, into the chemical circumstances connected with the a,griculture of Great Britain in its four main features ; namely— ♦i> . r^.u , P''^^^ct^'on of <'he cereal grain crops ; secondly, that of root crops ; thirdly that of the leguminous corn and fodder crop; and fourthly, and lastly, that of the consumption of food on the farm for its double produce of meat and manure. bo much then for the rationale and general plan of the experiments themselves u Ztu""^ propose to call attention to some of the results which they have afforded ub! iQ.^ io. J^^' T^ P*""^ ^^ *^^ ^^^"^*^ ""^ ^^^ ^h«at experiments of the harvests of 1844, 1845, and 1846, and of these seasons only, have been published ; those on tur- nips, only for the seasons 1843, 1844, and 1845 ; those on the leguminous crops not at all as yet ; and those onfeeding, only as far as sheep are concerned, and chiefly too in relation to the one pomt only of the increase of live weiglU obtained from a given quantity of food, or its constituents. Of the laboratory results, but few have been given m relation to any of these branches up to the present time. The vast accumu- lation of results indeed, will necessarily still further postpone the publication of them m any extended form ; and hence it seems the more desirable to take advantage of the present opportunity to attempt to bring together into one view some of the general mdieations which have been arrived at in relation to a few important points. w ith this view. It is to the field experiments on wheat that we shall chiefly confine our attention on this occasion ; for wheat, which constitutes the principal food of our population, IS with the farmer the most important crop in his rotation, all others beinc considered more or less subservient to it ; and it is, too, in reference to the production of this crop in agricultural quantity that the mineral theory of Baron Liebiff is perhaps more prominently at fault than in that of any other. It is true, that in the case of vegetation in a native soil, manured by art, the mineral constituent of the plants beine furnished from the soil, the atmosphere is found to be a mjfficient source of the nitro^^en and carbon; and it is the supposition that these circumstances oi natural vegetation aupW equally l>o the various crops when grown wvdcr cultivation that has led Baron Liebie to suggest that, if by artificial means we accumulate within the soil itself a sufiiciently lib- eral supply of those constituents found in the ashes of the plant, essentially soil constitu- ents, we shaU by this means be able in all cases to increase thereby the assimilation of the vegetable or atmospheric constituents in a degree sufficient for agricultural purposes. But agriculture is itself an aWi/?da/ process ; and it will be found that, as regards the production of wheat more especially, it is only by the accumulation within the soil iteelf Vol. 11. g "^ ^ I 114 MANURE. I '.-A I i\ tir r^ ii of nitrogen naturally derived from the atmosphere, rather than of the peculiarly soil constituenta, that our crops of it cain be incre^ised. Mineral substances will, indeed, materially develope tlie accumulation of vegetable or atmospheric constituents when applied to »onie of the crops of rotation ; and it is thus chiefly that these crops becom* subservient to the growth of the cereal grains, but even in these cases it is not the con- stituents, as found collectively in the ashes of the plants to be grmoiiy that are the most efficient in this respect ; nor can the demand which we find thus made for the produc- tion of crops '\ii agricultural quantity be accounted for by the mere idea of supplying the actual constitueuts of the crop. It would seem, therefore, that we can only arrive at correct ideas in agriculture by a close examination of the actual circumstances of growth of each particular crop when grown under cultivation. We now turn to the consideration of our experiments upon this subject. It has been said that all the ex- perimental fields were selected when they were in a state of agricultural exhaustion. iTie wheat fields, however, after having been manured in the usual way for tur- nips at the commencement of the previous rotation, had then grown barley, peas, wheat, and oats, without any further manuring ; so that when taken for experiment in 1844, it was, as a grain-producer, considerably more exhausted than would ordinarily be the case. It was, therefore, in a most favorable condition for the purposes of our experi- ments. "In the first experimental season, the field of 14 acres was divided into about 20 plots, and it was by the mineral theory that we were mainly guided in the selection of ma- nures : mineral manures were therefore employed in the majority of cases. Ammonia, on tlie other hand, being then considered as of less importance, was used in a feir instances only, and in these in very insignificant quantities. Rape-cake, as being a well recognised manure, and calculated to supply, besides some minerals and nitrogen, a certain quantity of carbonaceous substance in which both corn and straw so much abound, was also added to one or two of the plots. Table 1. — Harvest 1844. Summary. Dressed Ck>ni Total Straw Description of the Man ores. per Acre, Com per Acre, in Bushels per Acre, inlb& and Pecks. inlb& bush. pecks lbs. llM. Plot 3. Unmanured . . . - 16 923 1120 " 2. 14 tons of farm-yard manure 22 1276 1476 " 4. The ashes of 14 tons of farm manure 16 888 1104 " 8. Minimum produce of 9 plots, with ar- 1 tificial mineral manures - Superphosphate of lime 350 lbs. - Phosphate of potass 364 lbs. ' 16 1 980 1160 Plot 15. Maximum produce of 9 plots with ar- 1 tificial mineral manures - Superphosphate of lime 350 lbs. Phosphate of Magnesia 168 lbs. - ' ao potass 150 lbs 17 3^ 1096 1240 Silicate do. 112 lbs. Mean of the 9 plots with artificial mineral ma- nures 16 3* 1009 1155 Mean of 3 plots with mineral manures, and 65 lbs. each of sulphate of ammonia 21 1275 1423 Mean of 2 plots with mineral manures, and 150 lbs. and 160 lbs. of rape-cake respectively 18 1* 1078 1201 Plot 18. With complex mineral manure, 55 lbs. of sulphate of ammonia, and 150 lbs. of rape-cake 22 H 1368 1768 "The indications of the table are seen to be most conclusive, as showing what was the character of the exhaustion which had been induced by the previous heavy crop- ping, and what, therefore, should be the peculiar nature of the supply in a rational system of manuring. If the exhaustion had been connected with a deficiency of mineral constituents, we might reasonably have expected that by some one at least of the nine mineral conditions, — supposing in some cases an abundance of every min- eral constituent which the plant could require, — this deficiency would have been made up; but it was not so. " Thus, taking the column of bushels per acre as given in this summary a« our guide, it will be seen that whilst we have without manure only 16 bushels of dressed corn, we MANURE. 115 kave by farm-yard manure 22 bushels. The ashes, of farm-yard manure give, however no increase whatever over the unmanured plot Again, out of the 9 plots supplied with artihcial mineral manures, we have in no case an increase of 2 bushels bv this means; the produce of the average of the 9 being not quite 17 bushels. On the other hand we see that these addition to some of the purely mineral manures of 65 lbs. of sul- phate of ammonia— a verj.' small dressing of that substance, and containing only about 14 lbs of an.mon.a-has given us an average produce of 21 bushels. An insignificant addition of rape-cake too, to manures otherwise ineffective, has given us about 18i bushels; and when, as in plot 18., we have added to the inefficient mineral manur4 tWn . ^; *"f"»^»'a«»] salts, and a I'ttle rapenjake also, we have a produce greater man by the 14 tons of farm-yard manure. .^a7^^ Tt'^f^l^^ ""^ rape-cake used were small, and the increase attributable to it aJso small, but it nevertheless was much what we should expect when compared with that from the ammon.acal salts, if, as we believe is the case, the effect of rape-cake on grain-crops is due to the nitrogen it contains. ^ "Indeed, the coincidence in the slight or non-effect throughout the mineral series on the one hand, and of the marked and nearly uniform result of the nitrogenous sup- ply on the other, was most striking in the first year's experimental produce, and such as to lead us to give to nitrogenous manures in the second season even greater Dromi- ^.Tl r iT'' *^ ^^"^^ to minerals in the previous one. This is in some respects, perhaps, to be regretted, as had we kept a series of plots for some years continuously under minerals alone, the evidence, though at present sufficiently conclusive, would Have carried with it somewhat more of systematic proof. ^.r/^fTt^lf II: "^^ ^^^""^^ ?''t° * ^^"^ .''^^"^^ selected from those obtained at the har- vest of 1845 the second of the experimental series. By the tai>le it is seen tliat we have, at the harvest of 1845, a produce of rather more than 23 bushels without manure of any kind, instead of only 16 as in 1844 ; and in like manner the farm-yard manure Jives 32 bushels m 845 and only 22 in 1844. We have shown in a fo:^er dumber of the Journal how clearly these differences can be traced to variations in the climatic character of the season, but this is not the point under consideration just now. Table If.— Harvest 1845. Selected results. DescripUon and Quantities of the Manures per Acre. Dressed Com per Acre in Basbels and Peeks. Section 1. Plot 3. No manure .... 2. 14 tons of farm-yard manure Section 2. ** ha. No manure ..... " 56. Top-dressed with 252 lbs. of carbonate t»f ammonia (dissolved), at 3 times, during the spring .... Section 3. " 9 J Sulphate of ammonia 168 lbs. ) top-dress'd * { Muriate of ammonia 168 lbs. j" at once " 10. \ ^"'P''ate of ammonia 168 lbs. ( top-dress'd J Muriate of ammonia 168 lbs. j at 4 times. bosh, peeks. 23 0| 32 Oi 22 2i 26 3| 33 \\ 31 3i Total Corn per Acre, in lbs. lbs. 1441 1967 1431 1732 2181 1980 Straw per Acre, in lbs. lbs. 2712 3915 2684 3599 4058 4266 " We a.«^sume. then. 23 bushels or thereabouts to be the standard produce of the soil S ht^!?nn,Ti " «i''n«re, during this second experimental year ; and as part of plot ma l^iro ril T^'^^ With superphosphate of lime), and whfch i^now, also, without 3r^f n1«t% .h^' ""^'^ ^^'^'\ 2'^* ^"^^"^^ ""^ ^^^«^«^ ««^"' ^»'^ correctne^ of the ^Twl Plf V . P«™anently unmanured plot, is thereby fully confirmed, inf^ fu^nUnn 1 ' 5 prcviously two-thirds of au acre, was, in this second year, divided ^aZrT^\Kl\T'''''''^ ^^^^^«^ <'P^^* ^«') ^«»»g' »« J»«t said, unmanured, and !^^in, h/ ^ }-^ ) having supplied to it in silution, by top-dressings during the spring, the medtctnal carbonate of ammonia, at the rate of 260 lbs. per acre ; and it is rwS ^rnm'JrK' 'ZV"! '^""^ but highly volatile ammoniacal salt alone, the produce raised from 22 J bushels to very nearly 27 bushels! - In the next section of the table are given the results of plot* 9. and 10., the formw ot p 116 MANURE. which had in the previons year been manured by superphosphate of lime and a small quantity of sulphate of ammonia, and the latter by superphosphate of lime and silicate of potass. To each of the plots IJ cwt of sulphate and U cwt of muriate of ammo- nia were now supplied. Upon plot 9. the whole of the manure was top-dressed, at once, early in the spring ; but on plot 10. the salts were put on at four successive peri- ods. Theproduce obtained by these salts of ammonia alone is 33 bushels and three- eighths, when sown all at once, and nearly 32 bushels when sown at four different times — quantities which amount to about 10 bushels per acre more than was obtained with- out manure. In the case of No. 9., indeed, the produce exceeds by 1^ bushel that given by farm-yard manure, and in that of No. 10. it is all but identical with it And if we take the weights of total com, instead of the measure of the dressed corn, to which latter we chiefly refer, merely as a standard more conventionally understood. No. 10., by ammonia only, has given both more corn and more straw than the farm- yard manure, with all its minerals and carbonaceous substance. " Let us see whether this almost specific effect of nitrogen, in restoring, for the re- production of corn, a corn-exhausted soil, is borne out by the results of succeeding years. "We should have omitted all reference to the results obtained with the wheat ma- nure of Professor Liebig, had not the professor, in the new edition of his ' Letters,* whilst fully admitting the failure of the manure — the composition of which, to use his own words when commenting upon it, * could be no secret, since every plant showed by its ashes the due proportion of the constituents essential to its growth ' (page 482), — not expressed any doubt as to the principle involved in such a manure, but on the other hand, implied that the failure was due to a yet imperfect knowledge of the mechanical form and chemical qualities required to be given to the necessary con- stituents in order to fit them for their reception and nutritive action on the plant, rather than to any fallacy in the theory which would recommend to practical agri- culture the supply by artificial means of the constituents of the ashes of plants as manures. "The following table gives our selection of the resultfi of the third senson, 1846:— Table IIL — Harvest 1846. Selected Result.?. DMcription and Quantities of the Ifanures per Acre. Section 1. Plot 3. No manure . . . . " 2. 14 tons of farm-yard manure t( Section 2. 106. No manure " 10a. Sulphate of ammonia 224 Iba Dressed Corn per Acre, in Bushels and Pecks. Total Com per acre, in lbs. K 5a\ 5a\ Section 3. Ash of 8 loads of wheat straw . Ash of 8 loads of wheat straw, and top- dressed with 224 lbs. of sulphate of ammonia Section 4. 6a. Liebig's wheat manure 448 lbs. . 66. Liebig's wheat manure 448 lbs., with 112 lbs. each of sulphate and muriate of ammonia bash, pecks. 17 8| «7 0| 17 2J 27 1| 19 Oi 27 20 U 29 Of lbs. 1207 1826 1216 1860 1400 1967 Straw per Aero, in lbs. lbs. 1513 2454 1455 2244 1541 2309 1676 2571 At this third experimental harvest we have on the continuously unmanured plot, namely. No. 3., not quite 18 bushels of dressed corn, as the normal produce of the aeason ; and by ita side we have on plot 106 — comprising one-half of the plot 10 of the previous years, and so highly manured by ammoniacal salts in 1845 but now unmanured —rather more than 17 i bushels. The near approach, again to Identity of result from the two immanured plots, at once gives confidence in the accuracy of the experimente, and shows us how effectually the preceding crop had. ma practical point of view, reduced the plots, previously so differently circumstanced both as to manure and produce, to something Uke an uniform standard as regards MANURE. 117 their grain-producing qualities.- "We take this opportunity of particularly calling atten- tion to these coincidences in the amount of produce in the two unmanured plots of the different years, because it has been objected against our experiments, as already published, that confirmation was wanting as to the natural yield of soil and season. " Plot 2 has, as before, 14 tons of farm-yard manure, and the produce is 27^ bushels, or between 9 and 10 bushels more than without manure of any kind. " On plot 10a, which in the previous year gave by ammoniacal salts alone a pro- duce equal to that of the farm-yard manure, we have again a similar result : for 2 cwt. of sulphate of ammonia has now given 1850 lbs. of total corn, instead of 1826 lbs., which is the produce on plot 2. The straw of the latter is, however, slightly heavier than that by the ammoniacal salt "Again, plot 6a, which was in the previous season unmanured, was now subdivided : on one-half of it (namely, 5a*) we have the ashes of wheat-straw alone, by which there is an increase of rather more than 1 bushel per acre of dressed corn ; on the other half (or 6') we have, besides the straw ashes, 2 cwts. of sulphate of ammonia put on as a ton-dressing: 2 cwts. of sulphate of ammonia have, in this case, only increased the proauce beyond that of 5a* by 7| bushels of corn and 768 lbs. of straw, instead of by 9i bushels of corn and 789 lbs. of straw, which was the increase obtained by the same amount of ammoniacal salt on lOo, as compared with 106. It will be observed, how- ever, that in the former case the ammoniacal salts were top-dressed, but in the latter they were drilled at the time of sowing the seed ; and it will be remembered that in 1845 the result was better as to corn on plot 9, where the salts were sown earlier, than on plot 10, where the top-dressing extended far into the spring. We have had several direct instances of this kind in our experience, and we would give it as a sug gestion, in most cases applicable, that manures for wheat, and especially ammoniacal ones, should be applied before or at the time the seed is sown ; for although the ap- parent luxuriance of the crop is greater, and the produce of straw really heavier, by spring rather than autumn sowings of Peruvian guano and other ammoniacal manures, fet we believe that that of the corn will not be increased in an equivalent degree, ndeed, the success of the crop undoubtedly depends very materially on the progress of the underground growth during the winter months; and this again, other things being equal, upon the quantity of available nitrogenous constituents within the soil, without a liberal provision of which, the range of the fibrous feeders of the plant will not be such as to take up the minerals which the soil is competent to supply, and in •uch quantity as will be required during the after progress of tie plant for its healthy and favorable growth. "The next result to be noticed is that obtained on plot 6, now also divided into two equal portions, designated respectively 6a and 66. Plot No. 6 had for the crop of 1844 superphosphate of lime and the phosphate of magnesia manure, and for that of 1845 superphosphate of lime, rape-cake, and ammoniacal salts. For this the third ex periraental season, it was devoted to the trial of the wheat manure manufactured under the sanction of Professor Liebig, and patented in this country, " Upon plot 6a 4 cwts. per acre of the patent wheat-manure were used, which gave 20i bushels, or rather more than 2 bushels beyond the produce of the unmanured plot ; but as the manure contained, besides the minerals peculiar to it, some nitrogen- ous compounds, giving off a very perceptible odor of ammonia, some, at least, of the increase would be due to that substance. On plot 66, however, the further addition of 1 cwt each of sulphate and muriate of ammonia to this so-called "mineral manure** gives a produce of 29^ bushels. In other words, the addition of ammoniacal salt to Liebig's mineral manure has increased the produce by very nearly 9 bushels per acre beyond that of the mineral manure alone, whilst the increase obtained over the un- manured plot by 14 tons of farm-yard manure, was only 9^ bushels. " If, then, the * mechanical form and chemical qualities ' of the so-called * mineral manure' were at fault, the sulphate of ammonia has, at least, compensated for the de- fect; and even supposing a mineral manure, founded on a knowledge of the composi- tion of the ashes of the plant, be still the great desideratum, the farmer may rest con- tented, meanwhile, that he has in ammonia, supplied to him by Peruvian guano, by ammoniacal salts, and by other sources, so good a substitute. " It surely is needless to attempt further to justify, by the results of individual years, our assertion, that in practical agriculture nitrogenous manures are peculiarly a(Japted to the growth of wheat We shall therefore conclude this part of our subject by di- recting attention to the history of a few of the plots throughout the entire series of years, as compared with that of the unmanured plot during the same period. " In support of the view that leguminous plants do possess a superior power of reli- ance upon the atmosphere for their nitrogen, and, indeed, that it is to this property that they materially owe their efficacy in rotation with grain, we may refer to the admirable investigations into the chemistry of agriculture of M. Boussingault His experiments, however, have not received the attention which they merit from the II I 118 MANURE. ftli ! I ii a^cultunsts of this country ; probably on account of the small amounts of produce wmch he obtained. But it must be remembered that his investigation had for its ob- ject to explain the practices of agriculture as he found them in his own locality, before attemptmg to deviate from ite established rules. M. Boussingault states the rotation follow^-— ^^ ** Bechelbronn, and throughout the greater part of Alsace, to be as "Potatoes or beet-root;" "Wheat;" "Clover;" "Wheat-" and that the average of wheat so obtained is, after potatoes 19i bushels, after beet- root 17 bushels, after clover 24 bushels. Now we find by reference to his table that tne first crop of wheat, grain, and straw removed 17 lbs. of phosphoric acid and 24 lbs. oi potash and soda; the following clover crop. 18 lbs. of phosphoric acid and 11 lbs potash and soda; and after this removal of alkalis and phosphates by the clover a larger crop of wheat is obtained. Surely it would seem impossible to reconcile this result with a theory which supposes the produce of wheat to rise and fall with the quantity of minerals available within the soil. If, however, we admit that the first crop oi wiieat could not take up the mineral matters existing in the soil for want of nitro- genous supply, and that the clover crop, not being so dependent upon supplied nitro- gen, was able to take up the mineraU required for its growth, and that it moreover leic m tne soil sufficient ammonia, or its equivalent of nitrogen in some form, to give tne «ncrea«?rf crop of wheat, we have a much more consistent and probable solution of the results. Ihere is httle doubt that M. Boussingault could have increased his produce ot Wheat by means of araraoniacal salts : whether he could have done so economically 18 anther ^uestion^ depending of course upon the relative prices of grain and ammonii ihe striking effect of phosphoric acid upon the growth of the turnip, indeed, is a lact so well known to every intelligent agriculturist in Great Britain, that it would seem quite superfluous to attempt to illustrate it by any direct experiments of our own. However, as Professor Liebig has again, in the recent edition of his 'Letters ' expressed an opinion entirely inconsistent with such a result, we will refer to one or two of the results obtained in our experimental turnip-field, which bear upon the opinion he has reiterated as follows: thus, speaking of the exhaustion of phosphate Ot lime and alkaline phosphates bv the sale of flour, cattle, Ac, he says :— ' It is certain tnat tills incessant removal of the phosphates must tend to exhaust the land and dimmish Its capability of producing grain. The fields of Great Britain are in a state 01 progressive exhaustion from this cause, as is proved by the rapid extension of the cultivation of turnips and mangold-wurzel, plants which contain the least amount of tne pliosphates, and tukrkfork require the smallest QUANTrrv for their developme.nt * l^ow we do not hesitate to say that, however small the quantity of phosphates con- tained in the turnip, the successful cultivation of it is more dependent upon a large supply of phosphoric acid in the manure than that of any other crop. In the following table, then, is given the amounts of bulb, since 1843, of— *ir8t, the continuously unmanured plot; Secondly, that with a large amount of the superphosphate of lime alone each year ; and inirdly, that with a very liberal supply of potash with some soda and magnesia also, in addition to superphosphate of lime. MANURE. 119 1 Plot Plot Plot Yearsw continnoosly Un- with Superphosphate with 8ui)erphosphate manured. of Lime alone every of Lime and mixed I Year. Alkalis. Tonst cwts. qrs. lb8. Tons. cwts. qrs. Iba. Tons. cwts. qn. Ibai 1843 4 3 8 2 12 3 2 8 11 17 2 1844 2 4 1 1 14 8 5 13 2 1846 13 2 24 12 13 8 12 12 12 2 8 1846 — — - — •—. 1 18 3 10 1 20 1847 — _ _« — 6 11 1 5 IC 1848 — — — — 10 11 8 9 14 2 1849 — —. — — 3 15 8 13 2 8 1850 — — • — — 11 9 9 1 1 12 5 1 20 Totals. — — — — 65 16 1 1 62 Means. — — — — 8 4 2 4 1 15 2 20 "It 18 seen then, that in the third season, viz. 1845, the produce of the unmanured plot is reduced to a few hundred weight*, and since that period the size of the bulbs had been such that they have not been considered worth weighing. On the other hand on the plot with mperphosphate of lime alone for eight successive years, we have an average produce of about 8i tons of bulb ! varying, however, exceedingly, year by year acco^- ing to the season. We see, too, that by the addition to superphosphate of lime of a large quantity of the alkalis, much greater than could be taJcen off in the crop, the average produce is not so great by nearly half a ton as by the superphosphate of lime alone. It must be admitted that this extraordinary effect of superphosphate of lim« cannot be accounted for by the idea of merely supplying in it the actual constituents of the crop, but that it is due to some special agency in developing the assimilative processes of the plant This opinion is favored by the fact that in the case where the superphosphate of lime is at once neutralized by alkalis artificially supplied, the efficacy of the manure would seem to be thereby reduced. And from this again, we would gather that the effect of the phosphoric acid, as such, cannot be due mereU' to the liberation within the soil of its alkalis, or we should suppose that the artificial supply of these would at least have been attended with some increase of produce. But this is not the case, notwithstanding that by means of superphosphate of lime alone there has been taken from the land more of the alkalis in which the ash of the turnip so peculiarly abounds, than would have been lost from it in a century under the ordinary course of rotation and home manuring! Collateral experiments also clearly prove the importance of a liberal supply of organic substance rich in car6o» — which always contains a considerable quantity of nitrogen also — if wo would in practical agriculture increase the yield much beyond the amount which can be ob- tained by mineral manures alone ; and these conditions being fulfilled, the direct supply of nitrogen, on the other hand, is by no means so generally essential. And it is where we have provided a liberal supply of constituents for organic formations, in addition to the mineral manures, that we have found the use of alkalis not to be without effect ** But it is at any rate certain that phosphoric acid, though it forms so small a proportion of the ash of the turnip, has a very striking effect on its growth when applied as ma- nure; and it is equally certain that the extended cultivation of root crops in Great Britain cannot be due to the deficiency of this substance for the growth of corn, and to the less dependence upon it of the root crops, as supposed by Baron Liebig. " These curious and interesting facts in relation to the growth of turnips, as well at those which have been given in reference to wheat and to the leguminous crops, are eufficient to prove how impossible it is to form correct opinions on agricultural chemistry without the guidance of direct experiment in the field. And we are convinced that if Baron Liebig had watched the experiments which we have had in progress during the last eight years, he would long ago have arrived at conclusions in the main agreeing with tJnose to which we have been irresistibly led: and we are disposed to believe tliat had he even seen the more detailed accounts of our results given in our own papers in this Journal, instead of the mere reference to them made by Mr. Pusey, he would rather have accepted them, as a step in an inquiry to which his own researches auid writings had given such an impetus, than have designated them, as he has done, aa entirely without value. "So mucli, then, for the results of experiments in the field, and for the considera- tions in relation to the functional actions of plants, as bearing upon the character of the manure required for their growth in a course of practical agriculture. Let us now consider for a few moments what really are the main and characteristic features of practical ^riculture, as most generally followed in this country. " Let us suppose that the rotation adopted is that of turnips, barley, clover, wheat ; that the turnips and clover are consumed upon the farm by stock, and that the meat thus produced, 40 bushels of barley and 30 bushels of wheat,are all the exports from the farm, the manure from the consumed turnips and clover, and the straw, both of barley and of wheat being retained upon the farm. We have in this case, by the sale of grain, a loss of minerals to each acre of the farm of only 20 to 24 pounds ot potass and soda, and 26 to 30 pounds of phosphoric acid, in the course of the rotation, or an average of 5 to 6 lbs. of potass and soda, and ^\Ui1\\h% oi phosphoric acid per acre per annum. In the sale of the animals there would of course be an additional loss of phosphoric acid, though, especially if no breeding stock were kept, this would be even much less considerable than in that of the grain ; and the amount of the alkalis thus sent off the farm would, according to direct experiments of our own upon calves, bullocks, lambs, sheep, and {)igs, probably be only about one-fourth that of the phosphoric acid. It has, however, ong been decided in practical agriculture that phospnoric acid may be advantageously provided in the purchase of bones or other phosphatic manures, though in practice these are not found applicable as a direct manure for the wheat crop ; and as we have already said, even when employed for the turnip, its efficacy is not to be accounted for merely as supplying a sufficiency of that substance to be stored up in the crop. " In conclusion, then: if the theory of Baron Liebig simply implies that the growing plant must have within its reach a sufficiency of the mineral constituents of which it ia to be built up, we fully and entirely assent to so evident a truism ; but if, on the otlxer h«n«l, he would have it understood, that it is of the mineral constituents, as w^e^uldbe eoilcctivcli/ found in the ashes of the exported produce, that our soils are deficient rela- tively to other constituents, and that in the present condition of agriculture in Great I 120 MARBLE. s f this point, IS unfavorable to such a view. We have beforp«i«fI5 fi. ♦ v , Tver oi Mr Law« Ln'n "^r .r"?? "' ^''™'' ^"^'S- S'""' «>« experCn^ W- S ml X5 "y"! Dr. Gilbert have, as I hear, been disputed, I am bound to sav .trenXued bv a !„b '^' f^R^'o-^ ^''""'cy of those gentlemen has bieu ."J phTlofopher MJ„^DlT'°^^'''^'^^ft"'"^^^^^ company with that eminent £t w3ir' ir t ""?'»»• The extent of the experimental ground— the expenditure at which It has been kept up-the perseverance with which, year after year it his Zr^?' •.r°' ^^«"* me marble. Its gen- Marble effervesces with acids ; affords quicklime by calcination • ha* » *.«r,.i,«-^ i scaly fracture ; is translucent only on the very ed^es ; is ea^Ty cratched hv Zt'^ has a spec grav. of 2-7; admits of being sawn into slibs, and rece vis a bri,^iim nolllh* TTiese qualities occur united in only three principal varieties of limestone fnlr charoid limestone, so called from its fine granular texture rein^blinrth^^^^^ o.l'.Z' and which constitutes modem statuary marble, like that of Carrara -9 t hlf^v^^ limestone, consisting of a multitude of small facets formS of mt7e Sates* apd^d to' l'^ another m every possible direction, constituting the antique statu^ ma/ble'']^^^^ MARBLE. 131 Paros ; 3. in many of the transition and carboniferous, or encriniiic limestones, subordi. uate to the coal formation. The saccharoid and lamellar, or statuary marbles, belong entirely to primitive and transition districts. The greater part of the close-grained colored marbles belong also lo the same geological localities ; and become so rare in the secondary limestone for- mations, that immense tracts of these occur without a single bed sufficiently entire and compact to constitute a workable marble. The limestone lying between the calcareo-silicious sands and gritstone of the under oolite, and which is called Forest marble in England, being susceptible of a tolerable polish, and variegated with imbedded shells, has sometimes been worked into ornamental slabs in Oxfordshire, where il occurs in the neighborhood of Whichwood forest; but this case can hardly be con- sidered as an exception to the general rule. To constitute a profitable marble-quarry, there must be a large extent of homogeneous limestone, and a facility of transporting the blocks after they are dug. On examining these natural advantages of the beds of Carrara marble, we may readily understand how the statuary marbles discovered in the Pyrenees, Savoy, Corsica, &c. have never been able to come into competition with it in the market. In fact, the two sides of the valley of Carrara may be regarded as moun- tains of statuary marble of the finest quality. Gypseous alabaster may be readily distinguished from marbles, because it does not effervesce with acids, and is soft enough to be scratched by the nail ; stalagmitic alabaster is somewhat harder than marble, translucent, and variegated with regular stripes or undu- lations. Some granular marbles are flexible in thin slabs, or, at least, become so by being dried at the fire ; which shows, as Dolomieu suspected, that this properly arises from a diminu- tion of the attractive force among the particles, by the loss of the moisture. The various tints of ornamental marbles generally proceed from oxydes of iron ; but the blue and green tints are sometimes caused by minute particles of hornblende, as in the slate-blue variety called Turchino, and in some green marbles of Germany. The black marbles are colored by charcoal, mixed occasionally with sulphur and bitumen ; when they constitute stinkstone. Brard divides marbles, according to their localities, into classes, each of which contains eight subdivisions : — 1. Uni-colored marbles ; including only the white and the black. 2. Variegated marbles ; those with irregular spots or veins. 3. Madreporic marbles, presenting animal remains in the shape of white or gray spoih, with regularly disposed dots and stars in the centre. 4. Shell marbles ; with only a few shells interspersed in the calcareous base. 5. Lumachella marbles, entirely composed of shells. 6. Cipolin marbles, containing veins of greenish talc. 7. Breccia marbles, formed of a number of angular fragments of different marbles, united by a common cement. 8. Puddingstone marbles ; a conglomerate of rounded pieces. Jntiqne marbles. — The most remarkable of these are the following : — Parian marble, called lychnitcs by the ancients, because its quarries were worked by lamps ; it has a yel- lowish-white color; and a texture composed of fine shining scales, lying in all diiections. The celebrated Arundelian tables at Oxford consist of Parian marble, as well as the Medicean Venus. Pentelic marble, from Mount Penteles, near Athens, resembles the Parian, but is somewhat denser and finer grained, with occasional greenish zones, pro- duced by greenish talc, whence it is called by the Italians Cipolino statuario. The Parthenon, Propyleum, the Hippodrome, and other principal monuments of Athens, were of Pentelic marble ; of which fine specimens may be seen among the Elgin col- lection, in the British Museum. Marmo Greco, or Greek white marble, is of a very lively snow white color, rather harder than the preceding, and susceptible of a very fine polish. It was obtained from several islands of the Archipelago, as Scio, Samos, Lesbos, &c. Translucent white marble, Marmo statuario of the Italians, is very much like the Parian, only not so opaque. Columns and altars of this marble exist in Venice, and several towns of Lombardy ; but the quarries are quite unknown. Flexible white marble, of which five or six tables are preserved in the house of Prince Borghese, at Rome. Tht xvhite marble of Luni, on the coast of Tuscany, was preferred by the Greek sculptors to both the Parian and Pentelic. White marble of Carrara, between Specia and Lucca, is of a fine white color, but often traversed by gray veins, so that it is difficult to procure moderately large pieces free from them. It is not so apt to turn yellow as the Parian marble. This quaiTy was worked by the ancients, having been opened in the time of Julius CsBsar. Many antique statues remain of this marble. Its two principal quarries at the present day are those of Pianello and Polvazzo. In the centre of its blocks very Mmpid rock-crystals are sometimes found, which are called Carrara diamonds. As the finest qualities are becoming excessively rare, it has risen in price to about 3 guineas the 122 MARBLE. wbic foot. The White marble of Mount Hymettus, in Greece, was not of a very nure Tf Ims mirbTe ' " ' *' ^"''- '^^ ^^"^"' ^'^ ^^^^^^^^> ^" »»^^ ^^-"'^ M«s7u,S"S ^tocfe flnh>. marble, the i^ero a«/ico of the Italians. This is more intensely black than any of our modem marbles; it is extremely scarce, occurring only in sculp*n4d frti J?r^'^::^'^^*r«'*'«»^OT'«mof theancients,and /?a,«, a\/ W the Jl^fans very mlnte wS?e d^^^^^ a^'T^''°^""' ^"^^^J. interspersed with white veins and S very minute white dots, as if strewed over with grains of sand. There i«. in the Gri mam palace at Venice, a colossal statue of MarcSs A^rippa in rosso a^i^ wh kh wm formerly preserved in the Pantheon at Rome. Green antique marble^trdi T/ co Z^ kind of breccia, whose paste is a mixture of talc and limestone, whik ThfdTrWr^n fragments consist of serpentine. Very beautiful specimens of it ire preserved at Pa^ The best quality has a grass-green paste, with black spots of noble serpentfne b^' ^ITJf '''•1''^ '^' u '^. '^'^' ^'^ 'P'^^'^ ^^"^ «"^^>« ^rble, has a dark^gJee^^^^ m^^l^ T^.T" '^ 1"^- ^l^^H.^P^'^'^'^^ fragments of .rZ/rocAi changSfntow^^^ Twh VK .K k««^« only la small tablets. Leek marble ; a rare variet/of tha^X! of which there is a table m the Mint at Paris. Marmo verde pagliocco is of a yellowish aeep red, with numerous gray and while veins, is said to be found in Africa and highly the'vSk o^arr"' -f; ^'"r ""'*'^"' r.^'*^ ^'"^^ «"'^'^^ «^ '^' I^«»^n« ; eolor^ of tiie yolk of an egg, either uniform or marked with black or deep yellow rin^s It i. ^ok^thr^- ^ 'f^^^'"^ by Sienna marble. Bed and while antique marbles, found only among the ruins of ancient Rome. Grand antiqne, a breccia marble, containinff shell/ consists of large fragments of a black marble, traversed by veins or' linesTf a shin ie Cipohn IS a name given to all such marbles as have greenish zones produced by^reen tolc ; their fracture is granular and shining, and displays here and there plates of ^alc Purple antique breccia marble, is very variable in the color and size of its s^s* ^ gated marbles of Devonshire are generaUy reddish, brownish, mdl^^hh variouX* thpPW^ fK^""* Babbacombe, display a great variety in the mixture of 'their ^Xrs" ^^l^J^'^?:^\V'^'^^^ '? ^^^^^r ash^olored with black veins, or blackish-gray and XV n?Hr'^ ^'I^'k rT' '^^- """"^ "^" Marychurch exhibit marble qua^^s noTonly' of grea extent, but of superior beauty to any other iK Devonshire, bein- either of a dove-colored ground with reddish-purple and yellow veins, or of a ilack gJouni motUed with purplish globules. The green marble of Anglesea is not unlike the t"rrfc Zhco- Its colors being greenish-black, leek-green, and sometimes duU XpHsh irreffulari; blended with white. The white part is limestone, the green shS pVoceS from serpenune and asbestos. There are several fine varieties of mayetf De^byshke tl^ r« r iT^L" '^' "«»?bborhood of Moneyash, the light gray being rendered ext^^^^^^^ beautiful by the number of purple veins which spread upon'its polished surface in ek"am ^n^Z r^"'^''' ^"*J/' ""^''^ ^'•"^"^^"^ ^« '^^ "^"Ititude of entrochi, wkh whkh thU s^ne of wZ' ""T w'^^" ^^""l^-. ^"^'^ "^ '^' ^^«»^'^i«" «"d carboniferous lime Garbles Westmoreland is capable of being worked up into agreeable S A^L^t'^^^^^c "I'u* particularly fine variety of white marble is found in immense beds at ~ible o"f n'« '"^'^•• 'k ^ **'""*^^"^ ^'^-^'^y "^^^"^ «^ ^ ^^^ uniform gra^';„^d . ^"'^^P^.^^ of ^ fine polish, occurs on the north side of the ferry of Ballachulish in In t1 ee onfAr .^^'u^A' ^««^^^"tiful varieties is that from the hill of Shtr ch ?n Ih^t' .u^. ^)^ Hebrides. Its colors are pale blood-red, light flesh-red and reddish white, with dark green particles of hornblende, or rather sahlite ditfusJd' thrn.y^Tl X'l^' M- '^^^ '^"'"P^^^ "^^^^« «f I-^ i« of - fi"*^ grL, a iull whUe coloMme what resembling pure compact feldspar. It is said by Boumon to consist of anTnZ^f: sTts"'' The rt'^r'* '^f!^'^"'^ "^ '^'^ ^«"^^- '^ ^'^'^ yeliowirrgreenrs "^^^^^^ spots. The carboniferous limestone of manv of the coal basins in the lowirnrJrof w Tn n ""', Tr^^i^'" " ''^''^'''y ^^ ^"^»« ft>^ chimneT-pfeces ^ "' ^"'* m Ireland, the Kilkenny marble is the one best known hnv:»„ „ ki i j less varied with white marks produced by petrifactions The^snar whil"""** ""'''♦u' place of the shells, sometimes assumes a greenLh vellow Llnr^ a «^<:"Pf« the black marble has al'sobeen raised at CmylLfh in^he coi^^^^^ of Down A^r^nf ^^ k"** « the county of Tipperary, a fine pur/le marb^^'LTuTw^Twhen'^^^^^^ MARBLE. 123 rery beautiful. The county o. Kerry affords several variegated marbles, not unlike the Kilkenny. • j u n -j France possesses a great many marble quarries which have been described by Bmrd, ond of which a copious abstract is given under the article marble — Rees^ Cyclopedia. The territory of Genoa furnishes several beautiful varieties of marble, the most re- markable of which is the potzevera di Gerum, called in French the vert d'Egypte and vert de mer. It is a mixture of granular limestone with a talcose and serpentine substance disposed in veins ; and it is sometimes mixed with a reddish body. This marble was for- merly much employed in Italy, France, and England, for chimney-pieces, but its sombre appearance has put it out of fashion. Corsica possesses a good statuary marble of a fine close grain, and pure milky white- ness, quarried at Ornofrio ; it will bear comparison with that of Carrara ; also a gray marble (bardiglio), a cipolin, and some other varieties. The island of Elba has immense quarries of a white marble with blackish-green veins. Among the innumerable varieties of Italian marbles, the following deserve especial notice. The rovigio, a white marble found at Padua; the white marble of St. Jnlien, at Pisa, of which the cathedral and celebrated slanting tower are built ; the Biancone marble, white with a tinge of gray, quarried at Magurega for altars and tombs. Near Mergozza the white saline marble with gray veins is found ; with which the cathedral of Milan is built. The black marble of Bergamo is called paragone, from its black color, like touch- stone ; it has a pure intense tint, and is susceptible of a fine polish. The pure black marble of Como is also much esteemed. The polveroso of Pistoya, is a black marble sprinkled with dots ; and the beautiful white marble with bkick spots, from the Lago Maggiore, has been employed for decorating the interior of many churches in the Milanese. The Margorre marble found in several parts of the Milanese, is bluish veined with brown, and composes part of the dome of the cathedral of Milan. The green marble of Florence owes its color to a copious admixture of steatite. Another green marble, called verde di PradOy occurs in Tuscany, near the little town of Prado. It is marked with spots of a deeper green than the rest, passing even into blackish-blue. The beautiful Sienna marble, or brocatello di Siena, has a yellow color like the yolk of an egg, which is dis- posed in large irregular spots, surrounded with veins of bluish-red, passing sometimes into purple. At Montarenti, two leagues from Sienna, another yellow marble is met with, which is traversed by black and purplish-black veins. The Brema marble is yellow with white spots. The mandelato of the Italians is a light red marble with yellowish- white spots, found at Luggezzana, in the Veronese. The red marble of Verona is of a red rather inclining to yellow or hyacinth ; a second variety of a dark red, composes the vast amphitheatre of Verona. Another marble is found near Verona, with large while spots in a reddish and greenish paste. Very fine columns have been made of it. The occhio di pavone is an Italian shell marble, in which the shells form large orbicular spots, red, white, and bluish. A madreporic marble known under the name of pielra slellaria, much employed in Italy, is entirely composed of star madrepores, converted into a gray and white substance, and is susceptible of an excellent polish. The village of Bretonico, m the Veronese, furnishes a splendid breccia marble, comiwosed of yellow, steel-gray, and rose-colored spots. That of Bergamo consists of black and gray fragments in a greenish cement. Florence marble, called also ruin and landscape marble, is an indurated calca- reous marl. Sicily abounds in marbles, the most valuable of which is that called by the English stone-cutters, Sicilian jasper ; it is red with large stripes like ribands, white, red, and sometimes green, which run zigzag with pretty acute angles. Among the Genoese marbles we may notice the highly esteemed variety called portor, on account of the brilliant yellow veins in a deep black ground. The most beautiful kind comes from Porto-Venese, and Louis XIV. caused a great deal of it to be worked up for the decoration of Versailles. It costs now two pounds per cubic foot. Of cutting and polishing marble. — The marble saw is a thin plate of soft iron, continu- ally supplied during its sawing motion, with water and the sharpest sand. The sawing of moderate pieces is performed by hand, but that of large slabs is most economically done by a proper mill. The first substance used in the polishing process is the sharpest sand, which must be worked with till the surface becomes perfectly flat. Then a second, and even a third sand of increasing fineness is to be applied. The next substance is emery of progressive degrees of fineness, after which tripoli is employed ; and the last polish is given with tin-putty. The body with which the sand is rubbed upon the marble, is usually a plate of iron ; but for the subsequent process, a plate of lead is used with fine sand and emery. The polishing rubbers are coarse linen cloths, or bagging, wedged tight into an iron planing tool. In every step of the operation, a constant trickling supply of water is required. / 'y 11 124 MATCHES. Visitors of Derby may have an opportunity of inspecting Brown's extensive ma- chinery for cutting marble into many ornamental forms, which has been well described in Rees^s Cyclopaedia. Sir James Jelf patented, in 1822, a combination of machinery for cutting any de- scription of parallel mouldings upon marble slabs, for ornamental purposes ; in which tools, supplied with sand and water, are made to traverse to and no. Mr. Tullock obtained a paten t^ in 1824, for improvements in machinery for sawing and groovmg marble; the power being applied by means of toothed wheels bearing cranks, which gave the see-saw motion to the cutting iron plates. In November, 1829, Mr. Gibbs secured, by patent, an invention for working orna- mental devices in marble, by means of a travelling drill, guided by a mould of wood. Ac., in counter relief; and in April, 1833, Mr. G. W. Wilds obtained a patent for ma^ chinery, which consists of a series of circular cutters, for separating slabs from a block of marble; the block being advanced slowly to meet the cutters, by the progressive movenaent of a platform upon wheels, driven by the agency of a rack and pinion, as in the cylinder boring machine of the steam^ngine manufacturer. Sand and water must be supplied, of course, from a hopper, to these smooth-cutting discs of iron or copper. See Glass-Cutting. He proposes also to mould and polish marble, by applying a rotatory wheel or cylinder of anj shape to it, in its carrying frame. ^^5S^^'^^ ^® * variety of iron pyrites, containing generally a little arsenic. MARGARATES, are saline compounds of mai^aric acid with the bases. MARGARIC ACID, is one of the acid fats, produced by saponifying tallow with alkaline matter, and decomposing the soap with dilute acid. The term Marearic sic- nifies PEARLY-looking. ° The physical properties of the margaiic and stearic acids are very similar; the chief diflFerence is that the former is more fusible, melting at 140° F. The readiest mode of obtaining pure margane acid, is to dissolve olive oil soap in water, to pour into the solution a solution of neutral acetate of lead, to wash and dry the precipitate, and then to remove its oleate of lead by ether, which does not affect its margarate of lead. The residuum being decomposed by boiling hot muriatic acitl, affords margaric acid. When heated m a retort this acid boils. It is insoluble in water, very soluble in alcohol and ether ; it reddens litmus paper, and decomposes, with the aid of heat, the carbonates of soda and potash. MARGARIC ACID is obtained most easily by the distillation of stearic acid. The humidity at the beginning of the process must be expelled by a smart heat, otherwise explosive ebullitions are apt to occur. Whenever the ebullition becomes uniform the fire IS to be moderated. ' MARIXE ACID. See Muriatic Acid and Hydbochloric Acid. MARINE SALT. See Salt. MARL {Mariie, Fr. ; Mergel, Germ.), is a mixed earthy substance, consisting of carbonate of lime, clay, and siliceous sand, in very variable proportions ; it is some- times compact^ sometimes pulverulent According to the predominance of one or other of these three main ingredients, marls may be distributed into calcareous, clavey and sandy. See Limestone. ^ ^* MARQUETRY, is a peculiar kind of cabinetwork, in which the surface of wood is ornamented with mlaid pieces of various colors and forms. The marqueteur puts gold silver, copper, tortoise-shell, mother-of-pearl, ivory, horn, Ac, under contribution' These substances being reduced to laminae of proper thinness, are cut out into the desired forms by punches, which produce at once the full pattern or mould, and the empty one, which enclosed it ; and both serve their separate purposes in marquetry. For the methods of dyeing the woods, Ac, see Ivory. MARTIAL, signifies belonging to iron; from Mars, the mythological name of this metaL MASSICOT, is the yellow oxide of lead. MASTIC (Eng. and Fr. ; Masiix, Germ.), is a resin produced by making incisions in the Pistacia Lentiscus, a tree cultivated in the Levant, and chiefly in the island of Chios. It comes to us in vellow, brittle, transparent, rounded tears; which soften between the teeth ; with bitterish taste and aromatic smell, and a specific gravity of 1-OY. Mastic consists of two resins ; one soluble in dilute alcohol ; but both dissolve in strong alcohol. Its solution in spirit of wine constitutes a good varnish. It dis- solves also in oil of turpentine. See Varnish. MATCH^, chemical Put 40 grains of phosphorus into a wide-mouthed bottle. Add enough oil of turpentine to cover the phosphorus ; then mix in 10 grs. of flower of sulphur. Put the bottle into hot water until the phosphorus is entirely dis- solved ; stop the mouth of the bottle with a cork, and well shake the whole until it lias become cold ; afterwards pour off the supernatant oil of turpentine. Into the mixture of phosphorus which remains in the bottle dip the extremities of the matches, and, after some time, when they have become a little dried, dip them agaiu into the following mixture* matches. 1S5 Dissolve 30 grains of gum arable in a small quantity of water; add to it 20 grs. of ehlorate of potash, and mix them intimately together ; then again add It) grs. of soot previously mixed with a few drops of spirits of wine. In about 12 hours the matches will be perfectly dry, when they will ignite on rub- bing them over a rough surface. matches, INSTAN TANEOUS light, toithoiU Sulphur and withmit Noise. Boett- cher has published the following formula for the preparation of chemical matches, which ignite without noise : — Take of Gum Arabic - - - - - 16 parts. Phosphorus - - - - - 9 — Nitrate of potash - - - - 14 — Manganese - - - - -16 — Mix, so as to form a perfectly homogeneous mass. More recently, this chemist, being desirous of making a mass equally good, but at a lower price, tixed on the following formula : — Take of Phosphorus - - - - - 4 parts. Nitrate of potash - - - - 10 — Carpenter's glue - - - - - 6 — Minium, or red ochre - - - - 5 — Smalt - - - -- -2 — The glue is cut and soaked in a little water for 24 hours ; it is then put into a porcelain mortar, previously heated, so as to cause its liquefaction. The phosphorus is then added, afterwards the nitrate of potash, and lastly the minium and smalt, mixing the ingredients constantly with the pestle, until a perfectly homogeneous mix- ture is formed which may almost be drawn out in threads. During this operation the temperature must never be allowed to rise above 167** F., to prevent the inflammation of the particles of phosphorus. This paste may be applied to wood prepared for the purpose, or to amadou previ- ously dried for eight or twelve hours. ' Paper matches may be made, which will afford an agreeable odor on igniting, by wetting slips of pnper on both sides with tincture of benzoin, and then applying a small quantity of the above composition to their extremities, by means of a small brush. On rubbing one of these on a rough surface, the mass inflames and ignites the paper without the intervention of a coating of sulphur. Matches of wood may be made that will inflame without sulphur, by slightly car- bonizing the ends of them, by placing them against a red hot plate of iron, and then dipping them into melted wax. M. Diesel, of Ebersdorf, pupil of M. Wackenroder, has analyzed an excellent inflam- mable mass, and found the following proportions of ingredients in 100 parts: — Phosphorus - - - - - - 17 Nitrate of potash - - - - - 38 Minium - - - • - - 24 Glue - - - - - - 21 MATCHES, LUCIFER. According to Dr. R. Boettger, in Annalen der Chemie und Pharmacie, vol. xlvii. p. 334, take Phosphorus - - - . * - 4 parts. Nitre - - - - - - 10 — Fine glue - - - - - -6 — Red ochre, or red lead - - - - 5 — Smalt - - - - - -2 — Convert the glue with a little water by a gentle heat into a smooth jelly, put it into a slightly warm porcelain mortar to liquefy ; rub the phosphorus down through this gelatine at a temperature of about 140° or 150° Fahr. ; add the nitre, then the red powder, and lastly the smalt, till the whole forms a uniform paste. To make writing- paper matches, which burn with a bright flame and diffuse an agreeable odor, moisten each side of the paper with tincture of benzoin, dry it, cut it into slips, and smonr one of their ends with a little of the above paste by means of a hair pencil. On rubbing the said end after it is dry against a rough surface the paper will take fire, without the intervention of sulphur. To form lucifer wood matches, that act without sulphur, melt in a flat-bottomed, tin pan as much white wax as will stand one-tenth of an inch deep; take a bundle of wooden matches free from resin, rub their ends against a red hot iron plate till the wood be slightly charred ; dip them now in the melted wax for a moment, shake them well on taking them out, and finally dip them separately in the viscid paste. When dry, they will kindle readily by friction. i'ij 126 MATCHES. For the rapid manufacture of the wooden splints for lucifer matches a natpnf wo- granted to m. Reuben Partridge, in March, 1842. He employ aTrfoVaJ^m^^^^^ plate, having a steel face, strengthened by a bell-metal back • see r" 887 888^ Th« •ue of the perforations must depend on tLt of the desired splKtJhiy must be as close together as possible, that there may be a very small bknk spacT ^tweeu them otherwise the pW would afford too great resistance to the p^LTof the l^^^ By this construction, the whole area of the block of wood may be ^jmofe^sed latTr^^ ^^unk Tf^'^'T'^ T"^"^^ «"/ ^^''^ '^^^^^ '^' holes, Vhich7esl^^^^^^^^^ tersunk to favor the entrance and separation of the wooden fibres. ^"6''"^^ ^**"" and one thick^ The mode orpretirisb^ fit' '' k''k T^? ^^*^' «^^ ^^^^^^ ^^^S- resisting block or bearin^havhiran^aDertLp^nf,^^^ ^^^^ of the plate against a firm site Tide or back of he Dla^^ff ^. f ^ r "^"'i '? *5^ P***^' ««"^°g «»t on the oppo- the shapes a^d dimensrons o^the Wo"^ r * """'^i^"^' ^^ ^'«*^"«^ «?"»*«' agreeab^^to Manufacture ;}~^s^^^l rrs1s^TinT»^t''"y?'""'v^- V«^ ^^"- ^^S. ting the wood, which i{ done actordt^^M the manufacture of lucifers is the cut. hand or bymachinery Thb TwInl\hLll ' ".' ""^ *^' manufactory, either by the matchis in framel is in itsTirnlr^^ i . '^I^''* P''*'^.'" ""^ counting and placing for„PedLtheproArX.:froXl,'^*rt"roolM^^ of po ash I, con.,deredan essential ingredient inCLnd bu IT Z°-f ? • 't Nuinburg It has not been employed for a number of vear^iTi ^! i"-''"'^''*'"'"'.''' n.uch endangered the safety of the building, and theS ^f the 3^ T"* P™?*""'' property, of water, and of Jori^ltZX^Z^ ZTrTilt .Ir^JjSrS™ MEATS, PRESERVED. 127 is employed. If ignition be required without a fiame, the quantity of phosphorus is diminished, or nitrate of lead is added. The mixing is conducted in a water bath, and during this process, and as long as the phosphorus is being ground or " mullered," copious fumes are evolved. The dipping is performed in the following manner: — ^The melted composition is spread upon aboard covered with cloth or leather, and the work- man dips the two ends of the matches alternately that are fixed in the frame ; and as this is done with great rapidity, the disengagement of fumes is very considerable, and the more liable to be injurious, as they are evolved in a very concentrated form close to the face of the workmen. This department is generally left to a single workman ; and the average number that he can dip in an hour, supposing each frame to hold 3,000 matches, would be 1,000,000. After the matches have been dipped, they require to be dried. This is generally done in the room in which the former process is carried on ; and as a temperature of from 80° to 90° Fahr. is necessary, the greatest quantity of fumes is evolved at thia stage. When the matches are dried, the frames are removed from the drying room, and the lucifers are now ready to be counted out into boxes. As this is done with great rapidity, they frequently take fire, and, although instantly extinguished in the saw- dust or the water which is at hand, the occurrence gives rise to an additional and fre- quent evolution of fumes. MATRaSS, is a bottle with a thin egg-shaped bottom, much used for digestions ia chemical researches. MATTE, is a crude black copper reduced, but not refined from sulphur and other heterogeneous substances. MEADOW ORE, is concKoidal bc^ iron ore. MEATS, PRESERVED. The interest which has of late attached to the subject of such meats, warrants us in bringing under examination the principles and practice on which this important branch of industry is based. The art itself is of modern invention, and differs in every respect from the old or common modes of preserving animal food. These, as is well known, depend on the use of culinary salt, saltpetre, sugar, or similar substances, which, when in solution, do not possess the power of absorbing oxygen gas, and therefore cut off effectually all access of air to the meat they protect It might b« imagined that water alone would answer this purpose ; but the contrary is the case, for pure water absorbs oxygen, and is, therefore, all the less adapted for preserving meat, in proportion as it is free from saline matter, since it is then so much the more capable of combining with oxygen gas. Thus, snow, which is pure water crystallized, has a power of producing the panary fermentation when mixed with flour; and this it is able to do in consequence of the large quantity of gaseous oxygen which it containsi Similarly, rain water, and especially dew, will bring on the putrefaction of animal matters much sooner than spring wat^r ; and the vulgar prejudice respecting the effect of the moon's raya in accelerating the corruption of meat, is, beyond doubt, dependent upon the fact, that during clear moonlight nights, there is always a large deposition of dew; and this having fallen in a minutely divided state, possesses the largest amount of free oxygen, which pure or distilled water is capable of absorbing from the atmosphere, and, there- fore, haa a proportionate power of decomposing,— just as it also has of bleaching. Thus far our remarks have been applied solely to raw or uncooked meats; but the practical bearing of the object which we have in hand really points to those which are more or less cooked or preserved. It is with reference to provisions of this kind, that a parliamentary inquiry is now in progress ; and we cannot do better than show the great importance of such a subject to a maritime nation like Great Britain, by stating, that these provisions, when sound, are an absolute preventive of sea-scurvy, — a disease said, on good authority, to have destroyed more life, and to have done more damage to our navy, than all the enemies and tempests which that navy ever encountered. "We need not go far in search of evidence to prove the fearful havoc caused by this disease ; for we are well furnished by the history of Admiral Anson's memorable expedition, to damage the interests of Spain in the Pacific Ocean, by intercepting the annual treasure-ship or galleon on her return to Europe. In spite of every thing that care and experience could do, Anson tells us that he lost, in all, fully four-fifths of his people by scurvy. Of 400 men with whom the *• Centurion" departed from England, only 200 lived to reach the isl- and of Juan Fernandez, and no more than 8 of these were capable of doing duty ; and but for a supply of others at St Helena, there would not have been strength remain- ing to carry the ship to her anchorage. After describing, in the most pathetic manner, the dreadful sufferings of his crew, and rejoicing at the improvement caused by the so- journ at Juan Fernandez, the writer concludes,—" I therefore shall sum up the total of our loss since our departure from England, the better to convey some idea of our past sufferings and our present strength. We had buried on board the * Centurion,' since leaving St Helena, 292 men, and had remaining on board 214. This will, doubtless, appear a most extraordinary mortality ; but yet, on board the ' Gloucester' (his other ihip of war) it had been much greater: for, out of a much smaller crew than ©urs, they had buried the same number, and had only 82 remaining alive. It might," coa^ 128 MEATS, PRESERVED. morl favorably tharturjersinoi «hi ' / k ^^JP^'^^^l otherwW. for she escaped The real object of the vovate IZ^^V^^ buried 42, and has now 39 remaining." men, with ihich th^thre^ fessTleft F^lL^Uf ««°^°l«««/d; though out of 960 It is almost superfluourto rulHnwS f^ ^ 626 were dead before tEis time, to demonstrate tC erearutimv 1^^^ instances of the same kind ; though, in order ^ three other examplelas twffs ^vEw dr*''-" '^r*"^' ^' '"^'^'^^^^ ^wo Z ' trifling labor and resDonsibin/v 1,! , ^^-^ "^^u""^' ^^ '^^''tain quarters, to get rid of a our victualling SVaX^nis In oJtob?;".? this class of provisions altogether from harbor, and, before Ihe end of n?.K' V^l' ^^^ ^"^^ of Admiral Keppell came into lar. In 1779, the channel fleet uXs^^^^ r"i''f '''^? T^ ^ '^' ^^^P'^al at Has? tained more than 1,000 on board for Znl ^f^^K ^' '?\ ^'^^^ *^ ^^' ^^^P^^al, and re- months during a sibsequent vpar R n«T ""^ hospital accommodation. Within 4 asserts, that, lithin Snaee of ^^ v T'S- '^""^ ^ ^^^^"' *"^ S"' ^- Hawkins men had died of siurvj ^vLn IdSr^ ^"'""T ^«^l«<^g^ °ot 'ess than 10,000 a ten weeks' cruise in Ike Ty of^S ^To^ ment '''"T f ^. ^-'"^^^-'^ ^^er gross number ofadmissionsinto thf hl^V i *? .^° ^^""^ *^^ **^ ^^^ scurvy ; and the Now the highest mSirauthor?H^^^^^ ""^^ ^^'^^^' ^^ ^^^'» ^09 died, all expressed the ^pr^n th^^^^^^^^ ^^^^ «" ^he continent, have by thJ^ use of salt p^ovTsbns a„^^^^^^^ T'.'^^'^ '' altogether caused can be adduced to corroCaU ?he tnifh .f ^ * ^^^^^^ «»^y ^^^geons and officers humanity but also of «plf Jnf ^he truth of this view; therefore, not only motives of visions c^an be used thdr pln^^^^^ imperatively demand that, wherever unsalted pr^ tire nation. Such tne the c^asT^W^^^ ^' ^°'^^H^ ""' ^^ '^' ^«'«« <>^ the^««- art of preservinAnsLked nrntf: ' ^f^'"^^ necessary for us to inquire how far the iainty^of result,^XctatrcarwLrrntT-'- ^^/^^ee of unSbrmity. and cer! The first successful att^mnf of fi,*"^ their introduction into the navy. and due to ^e fn ventfve Xfof M ^ITT'Z'^ ""^^^'^^ ™^**« ''' «^ ^''^'^^ ^^^in. 1810. received from the boarJ of Art^^^'^A J^^''. gentleman, so long ago as the yeai francs for his discovery of a mod! f^ *"^ Manufactures of Paris the sum of 1^000 results of which harbTentheTamplvKrrg '""^"1 ""^ r^''^""'' substancesT tk^ navy. Shortly after thL periodTDLrM^^^^ J * prolonged experience in the French purpose of taking out a natent • tFftl^ "^"'^^ * 5?'"' ?""*"^ ^ ^^^^^ ^"^^^^ for the year 1811. In tLpaLnf however ^^ '^^ ^^ t^« that the patent-righrwL subsrqueatlvt .ridiculously wide, so much so, all kinds of fruit Seat Tnd v^!lli ^ mfringed with impunity. The claims included vessels. moreTr less fj'eed from a^^ ^57^" subjected to the Action of heat in closed presented in 1807 apremiumToak ts^^^^^ '^/ Society of Arts in London had without sugar for hoLHr s^a ^fo^^" ^",^.^I'^g^«"' ^"^S." * method of preserving fruit M. Appert^lthe valMity of Durant's n^T^^f 1'^ T^^^^ '^ ^^.'^^^ '^' «^°^« ^ ^hat of less so satUfactory were the result! If" "? ^a f "'" • ^"?^ '"^ *1"^«^^«"- ^everthe- that the patent wVevLtually n,?rVL,!S J^^ ' n ^"^ '^^^"^V^od. or mixed provisions. Gamble. L the sum ofTooS^^.^^^^^^^^ l^ ^^r^"' ^^"kinf Hall and make any experiment w^fh J , impenetrable to air. and have not ventured^ difficulties of this invention ii^^.L Gamb e, were able to overcome the primary vessels. Since that tfme bit littl'^lrjl'^^^^ successfully preserved in tin plat{ in the art. thou-h its princinlpl li! f ^^^^^^^^°' *^f ^^^, improvement, has been made From the res^ct^sTflX' [", ^clt^r^^^^^^^^ ^''^'''' been supposed! requisite to prevent fermentation • hnMf '• ^PP^^^f .^^f the absence of oxygen was wi'Jh fermenLblematStutut pr^^^^^^^^^ b' p-ent ;reror':r^Ti^^^^^^^ Although, therefore the excluln If' ^***^r'' ^^ *^^ T^"''^ ^^ *^« fermentation. IS not the only meal norl T?nd-T?h '^ ^" ^ T^""' -^ preventing putrefaction, it process of Appert ce'Cnly dol nff i 7''"'^ .t' '''°?^''* '"^ application. Tlie provisions he^ preservernor IrthU n.fnt^nl -"Pr^^^i"^ "^.l*"'^'^ ^^ ^V^^" ^^"^ ^he practised, with^uch marC success ^hvZ^l^^^^^ improve/ process still have had an opportuStrof examini'n^^h?!;^! ^ '^^^ ^'"^ ^/ ^*"^^^^' ^^ C^'"'^- We Gamble's pro^ions. anrh^vT^^iJl^/jrun^r^^^^^^^^^^^ MEATS, PRESERVED. 129 presence of oxygen gas, even in cases several years old. The quantity is, indeed, much le«8 than that in atmospheric air, but its existence is clear and undeniable. Hence we must look for some other theory than that which refers putrefaction to the presence of uncombined oxygen, if we wish to speculate upon the modus operandi of Gamble's method. Appert seems to have had a decided doubt as to the sufficiency of the oxygen theory, for he tells us that "fire has a peculiar property, not only of changing the combination of the constituent parts of vegetable and animal productions, but also of retarding, for many years at least, if not of destroying altogether, the natural tendency of these same products to decomposition." And this opinion is confirmed from many startling facts, which cannot be reconciled to the supposition that oxygen is the sole or even principal agent of decomposition. Thus milk, which has been merely scalded, will keep much longer from the eflFect of this process, even though freely exposed to, or purposely impregnated with, oxygen gas. All kinds of meat exhibit a similar result Again, very minute qualities of some mineral substances, as arsenic and corrosive sub- limate, or of organic matters, such as creosote, naphtha, and the volatile oils, have the same action when applied to meat or vegetables; and generally speaking, any thing which will coagulate albumen has a preservative power upon organic substances. So that oxygen appears to exert a decomposing force only when one or other of the forms of soluble albumen is present. Now. the method of Appei-t. as improved by Gamble (for the firm of Donkin. Hall, and Gamble no longer exists)! is to render the albumen of the meat or vegetable insoluble, and therefore scarcely, if at all. susceptible of the action of atmospheric oxygen. By this means the total exclusion of air from the tin cases IS rendered unnecessary, for even if a small quantity of air remain in the case, it will exert no more influence than happens to a piece of coagulatad albumen, or hard boiled white of egg, which, as is well known, may be exposed to the air for years without sensible alteration,though in its uncoagulated state it immediately putrefies. If; therefore, we were desired in a few words to express the essential characteristics of Gamble's process, it would not be by referring to the exclusion of air, but to the tho- rough coagulation of the albumen, that we should look for a satisfactory description. In this process the meat, more or less cooked, is placed, with a quantity of gravy in a tin veseel, capable of being hermetically sealed with solder; it is then heated, 'for some time m a bath of muriate of lime, and the aperture neatly soldered up. After this It IS again exposed to the action of the heated bath for a period, which varies with the BJze and nature of the contente of the vessels ; and to prove that this latter operation is really the most important of the whole, it sometimes happens that cases whith have begun to decompose are opened, resoldered, and again submitted to the muriate of lime bath, with the most perfect success, as regards the ultimate result There is, however, no little difficulty in effecting the thorough coagulation of albumen by heat^ when the quantity of albumen is small in proportion to the water present A long continued and rather high temperature is then needed; more especially if vinegar or lactic acid be present in the fluid, as these tend to retain the albumen in solution • much must therefore depend upon practical experience ; and it is not improbable that a heat in the bath but little higher than that of boiling water, would afford more uniform results, than would be obtained with a boiling saturated solution of muriate of lime This subject will, however, be more fully discussed when speaking of Goldner's processes! Although by no means free from occasional failures and certainly requiring im- provement, the system of Gamble has in practice worked well; and pi-ovisions have been kept m this way, for a period of more than twenty-six years, without the slight- est alteration in their particular qualities; and so well is this fact known and appre- ciated by British naval officers in general, that few vessels now leave our poi-ts with- out at least a proper supply for cabin use. It was found by Sir John Ross that a number of those cases of these preserved provisions left for many years upon Fury beach and exposed to excessive variations of temperature, were, nevertheless, perfectly sound and wholesome as food when opened. Guided probably by theoretical considerations, and too much impressed with the necessity of excluding ox;yrgen, a Mr. Goldner, some few years ago, adopted the idea originally conceived by Sir Humphry Davy, of enclosing cooked provisions in a com- plete vacuum. For this purpose the provisions, slightly cooked on the surface, were enclosed in canisters, similar to those of Gamble, but stronger, and provided with a small opening in the cover. At this moment a slight condensation was effected by the application of a cold and damp rag or sponge, and simultaneously with this the small opening was soldered up. In theory, nothing could seem better adapted to in- sure success; but, from the late parliamentary disclosures, it is evident that the prac- tical working of the invention affords any thin^ but a satisfactory result Nor is there much difficulty in conceiving how this may arise, as in the first place the application of a sudden heat to non-conducting materials is almost certain to give rise to that peculiar condition of water called the spheroidal state, and by which the interior of Vol. 11. 9 '^ J 130 MEATS, PRESERVED. the meat will be as thoroughly protected from the effect of heat as if no neat were apphed. Hence, even though steam in abundance may issue from the small opening m the cover, this is no proof that the meat in the centre of the vessel is even warmed • and still less does it warrant the supposition that the soluble albumen is thoronghlv coagulated; and without which, as we have stated, preservation is scarcely possible But, in addition to this, the application of a damp rag, in the way described, is, of all others, that by which a portion of air is most likely to be drawn into the vessel at the very moment when its total expulsion is taken for granted ; and both these circum- stances are more liable to happen with large than with small canisters If however the meat has been but partially cooked, in consequence of the water in it assuming the spheroidal condition, and, at the same time, atmospheric oxygen is included there can be no manner of doubt that putrefaction will occur, and run its course with the same rapidity as if no process whatever had been employed to prevent it That water so situ- ated in the substance of flesh is extremely prone to take on the form called spheroidal, needs no other proof than that the human hand may be deliberately passed through molten brass or iron with perfect impunity, and without even sensibly warming the lingers, as illustrated by M. Boutigny. It is not, therefore, enough to expose these canisters of provisions to heat, unless that heat be so gradually applied as to prevent the assumption of a spheroidal state by the watery portion of the food ; and we can- not help thinking that much of the disappointment and loss, consequent upon this kind of manufacture, has its origin in a want of attention to the ^ve circumstance. Where all power of circulation is prevented, as in the instance of these semi-solid meats, the tendency of the part in immediate contact with the source of heat to ac- ijuire a temperature capable of inducing the spheroidal condition, must be very great indeed ; and hence, m speaking of the muriate of lime bath, employed by Gamble we took occasion to hint, that more uniform results might perhaps be obtained by a'mw- derate than by a high temperature. The probability is, that no advantage is gained b^ exceeding 220° Fahr. ; and viewing tlie subject chemically, even this seems too liigh, where time is less an object than perfection of manufacture. It now remains only to offer a few remarks on the cooking of animal food and its apphcation to the wants of humanity. If flesh be digested for a short timi in cold water or brine, it parts with several of its most important constituents, and therefor© the practice of large and repeated washing is an unwise and foolishly fastidious opera- tion. Cold water dissolves from meat its soluble phosphates, its lactic acid, its krea- tine, and kreatinine, as well as its albumen. Without these constituents, however the meat neither is nor can be fitted to supply the muscular wear and tear of the human frame. In fact, one of these substances (kreatine) has evidently a singular connection with muscular energy, as it exists in greatest quantity in the flesh of animals mosi remarkable for muscular power and activity. To exclude it, therefore, is to introduce an element of weakness in the dietary of our seamen, that cannot fail, in the long run to show Itself; and hence the enormous prostration of strength which accompaniei the sea-scurvy ; for it happens that, as kreatine is soluble in brine, but little of this valuable element remains in the contracted and solidified mass, known by the name of salt junk, and employed as food in the Navy, upon much the same principle as that ascribed to alligators, who swallow stones to appease the cravings of an empty stomach. If, however, there is an error in the commencement of our Navy Tictnal- ling, there is still greater in the treatment of salt junk by its prejudiced and ill-in- formed consumers. Having had its albumen and other valuable matters removed by a cold solution of common salt, the junk is next deprived of its gelatine and osmazome by the action of boiling water; and this gelatine, which, with the kreatine and lactic acid, would greatly facilitate the process of digestion, is thrown away as worthless - and nothing but a hard mass of fibrine, scarcely, if at all, susceptible of assimilation by the powers of the animal economy, remains to give the appearance of food to the Eroduct, and, as it were, keep the word of promise to the eye, " to break it to the ope." The following quotation from Liebig's Researches on the Chernistru of Food may fitly occupy a place here : "It is obvious, that if flesh employed as food is again to become flesh m the body— if it is to retain the power of reproducing itself in its original condition— none of the constituents of raw flesh ought to be withdrawn from it during its preparation for foo»l. If its consumption be altered in any way if one of the constituents which belong essentially to its constitution be removed— a corres- ponding variation must take place in the power of that piece of flesh to reassume in the living body the original form and quality on which its properties in the living or- ganism depend. It follows from this, that boiled flesh when eaten tmthout the soup formed in boiling it, is so much the less adapted for nutrition, the greater the quantity of water m which it has been boiled, and the longer the duration of the boiling Under such circumstances, we cannot wonder that in spite of the acknowledged purity of sea-water, disease to a large extent should prevail in our Navy, and that when any active malady makes its appearance, the mortality should greatly exceed that of the MELLITIC ACID. 131 army under similar circumstances. This is a more natural sequence of the system pur- sued with regard to provisions ; and so far from abandoning altogether the emplo3'ment of preserved meats from the casual putrefaction of a few cases, it seems to us that a wise government would rather seek to run all this inconvenience, by calling in the aid of science, than fall back into a supine condition, when the interest of the nation so loudly calls for activity. After all, however, we can find no proof that these preserved provisions have failed, except in the case of Goldner; for there are many other manu- facturers, both in this country and in France, whose productions no more warrant the ban of exclusion, than a trifling accident deserves to be deemed a deliberate crime. If failure be a sufficient reason for interdicting further operations, how shall we account for the persevering assiduity of our dockyard authorities in respect to ship-building f We sincerely hope that the parliamentary committee, now sitting, will not separate until the whole subject of preserved provisions has been fully and impartially investigated in all its details. MEDALS. For their composition, see Bronze and Copper. The Industrial Exhibition of 1851 has called into requisition, among others, the skilled labor of ^Jie medallist die-sinker. As a consequence, medals of all kinds and prices are being produced. A medal die is thus forrnea:— -Steel of an uniform texture and kind being selected, it is forged, softened by annealing, and the face and check for the collar turned. The design approved o1^ the die-sinker proceeds to cut away those parts of the greatest depth by means of small chisels: the more minute details are taken out by gravers, chisel-edged, and gauged steel tools fitted into wood handles very short, and to fit the palm of the hand. As the work proceeds, proofs are taken in wax ; when defective in form the cutting is corrected, deficient in relief it is sunk deeper. It will of course be borne in mind that, what will be relievo in the medal, is in- taglio in the die. The inscription is introduced by means of small letter-punches. Then follows the hardening of the die, a stage of the business the most critical, as a defect in the steel will at once be made apparent thereby, and the labor of months rendered useless in a few minutes. If the die endures this, it has only another test, viz., the making of a " hub," or copy of the die in steel, and used for the correction of the duplicate copies of the die. The danger in this case arises from the want of uniformity of hardues3. If irregular, one portion of the die must suffer, and become valueless. Medal-making or stamping is thus carried on: — ^The press consists of a large and close threaded screw, to the top of which a large wheel is attached horizontally. The bed of the press is fitted with screws to secure the die in its place ; when this is done the collar which gives the thickness of the medal is fitted on, the die forming the reverse of the medal is attached to the screw ; a blank (a piece of metal cut out to form the medal) is then introduced. Motion is imparted to the wheel, which operates on the screw; a blow is given, and if the impression is soft and shallow, a medal is C reduced; but if deep, repeated blows are given to bring the impression up. When ronze or silver is the material in which the medal is to be produced, as many as 20 or even 30 blows are necessary. The medal is then taken out of the press, the edge turned, and the operation is complete. By collar die, is meant that portion which gives the thickness to the medal or coin to be struck. All medal dies are of three parts, viz., the reverse, obverse, and collar. The smaller class of dies are cut in steel entirely, the lai^er kinds for brass foundry «nd other purposes are •* laid " or covered with steel on a foundation of iron. When indentations occur, the die is what is called " fullered," or hollowed, and the steel follows the same in a parallel thickness. MEERSCHAUM (Germ. ; sea-froth, Eng. ; Ecume de Mer Moffnesie carbonatee sili- ei/ere, Fr.), is a white mineral, of a somewhat earthy appearance, always soft, but dry to the touch, and adhering to the tongue. Specific gravity^, 2'6 to 3*4; affords water by calcination ; fuses with difficulty at the blowpipe into a white enamel; and is acted upon by acids. It consists, according to Klaproth, of silica, 41 -5 ; magnesia, 1 8"25 ; water and carbonic acid, 39. Other analysts give, silica 60, magnesia 25, water 26. It occurs in veins or kidney-shaped nodules, among rocks of serpentine, at Egri- bos, in the island of Negropont, Eski-Schehir in Anatolia, Brussa at the foot of Mount Olympus, at Baldissero in Piedmont, in the serpentine veins of Cornwall, Ac. When first dug up, it is soft, greasy, and lathers like soap ; and is on that account used by the Tartirs in washing^their linen. The well known Turkey tobacco-pipes are made from it, by a process analogous to that for making pottery ware. The bowls of the pipes, when imported inte Germany, are prepared for sale by soaking them first in tallow, then in wax, and finally by polishing them with shave-grass. MELLITE (Eng. and Fr. ; Hontgstein, Germ.) See Honeystone. MELLITIC ACID, which is associated with alumina in the preceding mineral, crystalliies in small colorless needles, is without smell, of a strongly acid taste, perma^ nent inthe air, soluble in water and alcohol, as also in boiling hot concentrated sul- phuric acid, but is decomposed by hot nitric acid, and consists of 50'21 carbon, and II 132 MERCURY. 49*79 oxygen. It is carbonized at a red heat, without the production of any inflammo- ble oil. MELLON is a new compound of carbon and azote, discovered by M . Liebig, by heating bi-snlpiio-cyanide of mercury. The mellon remains at the bottom of the retort under the form of a yellow powder. MENACHANITE, an ore of titanium, found in the bed of a rivulet which flows into the valley Menacan, in Cornwall. MERCURY or QUICKSILVER. This metal is distinguished by its fluidity at com- mon temperatures ; its density = 13'6 ; its silver blue lustre ; and its extreme mobility. A cold of 39° below zero of Fahrenheit, or — 40° Cent., is required for its congelation, in which state its density is increased in the proportion of 10 to 9, or it becomes of spec grav. 15-0. At a temperature of 656° F. it boils and distils off" in an elastic vapor ; which, being condensed by cold, forms purified mercury. Mercury combines with great readiness with certain metals, as gold, sUver, zinc, tin, and bismuth, forming, in certain proportions, fluid solutions of these metals. Such mer- curial alloys are called amalgams. This property is extensively employed in many arts; as in extracting gold and silver from their ores ; in gilding, plating, making looking-glasses, &c. Humboldt estimates at 16,000 quintals, of 100 lbs. each, the quantity of mercury annually employed at his visit to America, in the treatment of the mines of New Spain ; three fourths of which came from European mines. The mercurial ores may be divided into four species : — 1. Native quicksilver. — It occurs in most of the mines of the other mercurial ores, in the form of small drops attached to the rocks, or lodged in the crevices of other ores. 2. Argental mercury^ or native silver amalgam. — It has a silver white color, and is more or less soft, according to the proportion which the mercury bears to the silver. Its density is sometimes so high as 14. A moderate heat dissipates the mercury, and leaves the silver. Klaproth states its constituents at sDver 36, and mercury 64, in 100 ; but Cordier makes them to be, 27| silver, and 72| mercury. It occurs crystallized in a variety of forms. It has been found in the territory of Deux-Ponts, at Rozenau and Niderstana, in Hungary, in a canton of Tyrol, at Sahlberg in Sweden, at Kolyvan in Siberia, and at Allemont in Dauphiny ; in small quantity at Almaden in Spain, and at Idria in Camiola. By the chemical union of the mercury with the silver, the amalgam, which should by calculation have a spec. grav. of only 12-5, acquires that of 14*11, ac- cording to M. Cordier. 3. StUphuret of mercury, commonly called Cinnabar, is a red mineral of various shades ; burning at the blowpipe with a blue flame, volatilizing entirely with the smell of burning sulphur, and giving a quicksilver coating to a plate of copper held in the fumes. Even the powder of cinnabar rubbed on copper whitens it. Its density varies from 6*9 to 10*2. It becomes negatively electrical by friction. Analyzed by Klaproth, it was found to consist of mercury 84*5, sulphur 14*75. Its composition, viewed as a bisulphuret of mercury, is, mercury 86*2, sulphur 13'8. The finest crystals of sulphuret of mercury come from China, and Almaden in Spain. These contain, according to Klap- roth, 85 per cent, of mercury. A bitumiTtous sulphuret of mercury appears to be the base of the great exploration of Idria ; it is of a dark liver-red hue ; and of a slaty texture, with straight or twisted plates. It exists in large masses in the bituminous schists of Idria. M. Beurard mentions also the locality of Monster Appel, in the dutchy of Deux-Ponts, where the ore includes im- pressions of fishes, curiously spotted with cinnabar. The compact variety of the Idria ore seems very complex in composition, according to the following analysis of Klaproth: — Mercury, 81-8; sulphur, 13*75 ; carbon, 2*3 ; silica, 0*65 ; alumina, 0*55 ; oxyde of iron, 0*20 ; copper, 0*02 ; water, 0*73 ; in 100 parts. M. Beurard mentions another variety from the Palatinate, which yields a large quantity of bitumen by distillation ; and it was present in all the specimens of these ores analyzed by me for the German Mines Company. At Idria and Almaden the snlphurets are ex« tremely rich in mercury. 4. Muriated mercury, or the Chloride of mercury, commonly called Horn mercury. This ore occurs in very small crystals of a pearl-gray or greenish-gray color, or in smzdl nipples which stud, like crystals, the cavities, fissures, or geodes among the ferruginous gangues of the other ores of mercury. It is brittle, and entirely volatile at the blow-pipe, characters which distinguish it from horn silver. The geological position of the mercurial ores, in all parts of the world, is in the strata which commence the series of secondary formations. Sometimes they are found in the red sandstone above the coal, as at Menildot, in the old dutchy of Deux-Ponts, at Durasno in Mexico, at Cuen^a in New Granada, at Cerros de Gauzan and Upar in Peru ; in the subordinate porphyries, as at Deux-Ponts, San Juan de la Chica in Peru, and at Cerro-del-Fraile, near the town of San Felipe ; they occur also among the strata below, or subordinate to the calcareous formation, called zechttein, in Germany, or MERCURY. 188 among the accompanying bituminous schists, as at Idria in Camiola ; and, lastly, they form masses in the zechstein itself. Thus, it appears that the mercurial deposites arc confined within very narrow geological limits, between the calcareous beds of zechstein, and the red sandstone. They occur at times in carbonaceous nodules, derived from the decomposition of mosses of various kinds ; and the whole mercurial deposite is occasion- ally covered with beds of charcoal, as at Durasno. They are even sometimes accompanied with the remains of oi^anic bodies, such as casts of fishes, fossil shells, silicified wood, and true coal. The last fact has been observed at Potzberg, in the works of Drey-Koenigszug, by M. Brongniart. These sandstones, bituminous schists, and indurated clays, contain mercury both in the state of sulphuret and in the native form. They are more or less penetrated with the ore, form- ing sometimes numerous beds of very great thickness ; while, in the more ancient or the primitive formations, these ores exist only in very small quantity associated with tin. Mercury is, generally speaking, a metal sparingly distributed in nature, and its mines are very rare. The great exploitations of Idria in Friuli, in the county of Goritz, were discovered in 1497, and the principal ore mined there is the bituminous sulphuret. The workings of this mine have been pushed to the depth of 280 yards. The product in quicksilver might easily amount annually to 6000 metric quintals=600 tons British ; but, in order to uphold the price of the metal, the Austrian government has restricted the production to 150 tons. The memorable fire of 1803 was most disastrous to these mines. It was ex- tinguished only by drowning all the underground workings. The sublimed mercury in this catastrophe occasioned diseases and nervous tremblings to more than 900 persons in the neighborhood. Pliny has recorded two interesting facts : 1. that the Greeks imported red cinnabar (torn Almaden 700 years before the Christian era ; and 2. that Rome, in his time, annu- ally received 700,000 pounds from the same mines. Since 1827, they have produced 22,000 cwts. of mercury every year, with a corps of 700 miners and 200 smelters ; and, indeed, the veins are so extremely rich, that though they have been worked pretty con- stantly during so many centuries, the mines have hardly reached the depth of 330 yards, or something less than 1000 feet. The lode actually under exploration is from 14 to 16 yards thick ; and it becomes thicker still at the crossing of the veins. The totality of the ore is extracted. It yields in their smelting works only 10 per cent, upon an average, but there is no doubt, from the analysis of the ores, that nearly one half of the quicksilver is lost, and dispersed in the air, to the great injury of the workmen's health, in conse- quence of the barbarous apparatus of aludels employed in its sublimation ; an apparatus which has remained without any material change for the better since the days of the Moorish dominion in Spain. M. Le Play, the eminent Ingenieur des Mines, who published, in a recent volume of the Annales des Mines, his Itineraire to Almaden, says, that the mercurial contents of the ores are notablemeni plus elevees than the product. These veins extend all the way from the town of Chillon to Almadenejos. Upon the borders of the streamlet Balde Azogues, a black slate is also mined which is abun- dantly impregnated with metallic mercury. The ores are treated in 13 double fur- naces, which I shall presently describe. « Le mercure," says M. Le Play, « a sur la sante des ouvriers la plus funeste influence, et P on ne pent se defendre d' un sentiment penible en voyant V empressement avec lequel des jeunes gens, pleins de force et de sante, se disputent la faveur d' aller chercher dans les mines, des maladies cruelles, et souvent une mort prematuree. La population des mineurs d' Almaden meritent le plus haut interet.** These victims of a deplorable mismanagement are described as being a laborious, simple-minded, virtuous race of beings, who are thus condemned to breathe an atmosphere impregnated far and near with the fumes of a volatile poison, which the lessons of science, as I shall presently demonstrate, might readily repress, with the effect of not only protecting the health of the population, but of vastly augmenting the revenues of the state. These celebrated mines, near to which lie those of Las Cuebas and of Almadenejos, were known to the Romans. After having been the property of the religious knights of Calatrava, who had assisted in expelling the Moors, they were farmed off' to the celebrated Fugger merchants of Augsbourg; and afterwards explored on account of the government, from the date of 1645 till the present time. Their produce was, tUl very lately, entirely appropriated to the treatment of the gold and silver ores of the new world. The mines of the Palatinate, situated on the left bank of the Rhine, though they do not approach in richness and importance to those of Idria and Almaden, merit, however, all the attention of the government that farms them out. They are numerous, and varied in geological position. Those of Drey-Koenigszug, at Potzberg, near Kussel, deserve par- ticular notice. The workings have reached a depth of more than 220 yards ; the ore be- ng a sandstone strongly impregnated with sulphuret of mercury. The produce of these mines is estimated at about 30 tons per annum. 134 MERCURY. The mines of Guancavelica. in Peru ar^ tlip mr»ro ;««« .• , . directly employed in treating C oZV7oiiLT7ayerZtt^\^' '^Z'-' ^\^'"'' ?'' aceo^ng to He,„, about .be be£„iV «/ 1^ :?al°^S^?oT T^-r/p-S r ^T\}? ^^^ ^^^^ century, the method called per descermiin was the onlv nn^ in «.^ «nj ici^ujjuiscu. nence, oeiore IbSo. some smeltmo' wnrV* nf iv>a r>o,io,«: » u j up the method per desceLum, which was hoover stmrPi«!nJ^ Palatmate had given stituted for it the furnaces caUed ZkrUs At fir^'t llh *" l"*'"* ' *"^ ^^^^ ^"*»- in these furnaces; but they were fot^ccee^dldty^r^^^^^ Tl^^e'ZUS^lZt mode of operating is still in use. At Idria, in the year 1750 « ajpj ,^;ern ! '* There exist, therefore, three kinds of apparatus for the distillation of mprn„rv i ♦!. furnace called a gallery; 2. the furnace w^th aZitrfL and ^11?^ f '^^'^''^ '• }' ^f Idria I shall describe each of these briefl^insut^^^^^^^ '* /'' "^'"^^ '^^^«''«''" ^^ 1' I' umace called Gallery of the Palatinate. The rnnstmrtJ^n «f ^ 'T ^^'^ of^ucurbTu'pon thelratel'/ y»g«. osy, 890, which receives the pit-coal emnloved ns fnoi tt«,i« «u- »/«^«^ *- y > an a.h.pit d! Fig. 891, which exWbits an elevation ofthe ^,l"ce lo!n^^^ ash.pit, as well as one of the two doors c, by which the full is rroTi S^TthTgrate ^^^ »^« ?/• Openings .., (j^. 889,f are left over the top arch of the fur- nace, whereby the draught of air may receive a suitable direction. The grate of the fireplace extends over the whole length of the fur- nace, fig. 890, from the door c to the door /, situated at the opposite extremity. The furnace called gal- lery includes commonly 30 cucurbits, and in some establishments even 62. Into each are introduced from 56 to 70 pounds of ore, and 15 to ^° .P?"n «« ^^^'^^ted 5 mercury pass, on the one side! Lto^tces'siVe taJ^L^^^^^^ '^^^ ""^ ^^^ ^^Po« -^ fghijkl are passages which permit the circulation nr fv MERCURY. 187 openings on each side of the same furnace, and in each half of the apparatus, which is double, as yig. 897 shows ; the spaces without letters being in every respect similar to the spaces mentioned below. Fig. 897 is double the scale of yig. 896. m m', yig. 897, are basins of reception, distributed before the doors of each of the chambers/ kf k'. The condensed mercury which flows out of the chambers is conveyed thither, n n' is a trench into which the mercury, after being lifted into the basins m, is poured, so that it may run towards a common chamber o, in the sloping direction indicated by the arrows, o leads to the chamber where the mercury is received into a porphyry trough ; out of which it is laded and packed up in portions of 50 or 100 lbs. in sheep-skins prepared with alum, pp', fig. 896, are vaulted arches, through which a circulation may go on round the furnace a b c d, on the ground level, q q' are the vaults of the upper stories, r r^, fig. 898, vaults which permit access to the tunnels e' c", fig. 896. s s' and / t',fig. 898, are the doors of the chambers/ fc and/ k'. These openings are f hut daring the distillation by wooden doors faced with iron, and luted with a mortar of clay and lime, u u' is the door of the vaults 1 to 7 of the furnace represented in fig. 896. These openings are hermetically shut, like the preceding, v v', fig. 896, are superior opeuings of the chambers, closed duing the operation by luted plugs ; they are opened afterwards to facilitate the cooling of the apparatus, and to collect the mercurial soot, xy z, fig. 899, are floors which correspond to the doors u u' of the vaults 1 to 7, 899 fig. 898. These floors are reached by stairs set up in the different parts of the building, which contains the whole apparatus. On the lower arches the largest blocks of metalliferous rock are laid ; over these the less bulky fragments are arranged, which are covered with the shivers and pieces of less dimension. On the middle vaults, the small ore is placed, distributed into cylindrical pip- kins of earthenware, of 10 inches diameter and 5 inches depth. The upper vaults receive likewise pipkins filled with the sands and pastes called schlich. In 3 hours, by the labor of 40 men, the two double sets of apparatus are charged, and all the apertures are closed. A quick fire of beech-wood is then kindled ; and when the whole mass has become sufficiently heated, the sulphuret of mercury begins to vapor- ize ; coming into contact with the portion of oxygen which had not been carbonated, by combustion, its sulphur burns into sulphurous acid, while the mercury becomes free, passes with the other vapors into the chambers foi* condensing it, and precipitates in the liquid form at a greater or less distance from the fire-place. The walls of the chambers and the floors, with which their lower portion is covered, are soon coated over with a black mercurial soot, which, being treated anew, furnishes 50 per cent, of mercury. The distillation lasts from 10 to 12 hours ; during which time the whole furnace is kept at a cherry-red heat. A complete charge for the two double apparatus, consists of from 1000 to 1300 quintals of ore, which produce from 80 to 90 quintals of running mercury. The furnace takes from 5 to 6 days to cool, according to the state of the weather ; and if to that period be added the time requisite for withdrawing the residuums, and attend- ing to such repairs as the furnace may need, it is obvious that only one distillation can be performed in the course of a week. In the works of Idria, in 1812, 56,686 quintals and a half of quicksilver ores were dis- tilled, after undergoing a very careful mechanical preparation. They afforded 4832 quin- tals of running mercury ; a quantity corresponding to about 8^ per cent, of the ore. Thes^ smelting works are about 180 feet long and 30 feet high. Upon the preceding three systems of smelting mercurial ores, I shall now make some observations. It has been long well known, that quicksilver may be most readily extracted from cinnabar, by heating it in contact with quicklime. The sulphur of the cinnab^ com- I 138 MERCURY. mJ^.l^^ ^\''"' J'^!?!'*** prescribed for distilling the ore along with quicklime are r«. SMaW^ri"- •" '1^' P'^"*^^^ ^^ LandsbergV Obermoschel, ther?ra «eat wastt mJp^?\ ?*'*^;k^ ^^^ """^erous small cucurbits ; there is a gr^at waste of fuel inthP Sih. ri? "^ '^''" S,^ ^''^' ^^^t^ °^ '"^^^"ry ^y the imperfect iS of the retorts Xbi;::S^^^^^^^^ condensation of ^the mercurii [^^^TZ rtgdXtl?hTo'"ctr ^^°"^ '^"^ '"^"^'^ "'^^^^ -^^^^ -^ neverV"tnd1r^^ :£ menrsS^f ti^.*"'^ inconveniences and sources of loss, the proper chemical arrange- meats suited to the present improved state of the arts ought to be adopted bvwhfrh itamus mfo hf'"^/ "i''' ""^^- ^^r^^i-d to the%tmosrextent^^'TL oily qmcklime, may be easily introduced, from a measured heap, by means of a shovel (When . e^:^" d"oeT;o''t''"colr.hV c'aTcarurmlt.t Zr/bl' o'S^" S'T rtmTave^T?h•*;^^"'" "="'"'= '"'' ?''•" •« I"" i-to eieh of .Le aboTe^etm a'd' f„ .hi / * • ■ "^^ ?f '™P'y space for the expansion of volume which may tMcVnllee the rfou/.? Vlh; T' '^P"*^^?."* * eheap and powerful apparatus which I contrived at T «n^T the German Mines Company of London, and which is now mouM^ It Landsberg, near Obermoschel, in the Bavarian Rhein-K^-eis. mounted at J'lg. 900, IS a section parallel to the front elevation of three arched benches of retorts. 900 s ^m.i^^ T- [Z33C Of ^the Size above sr^^^^^^^^ 3 retorts, of the form represented by cpal or wcixJ, to thrthree rlVts Th^^tnA« ''^^^^l''-,f "^"^-^ ^^^'^^^^ ^^^^^tion bj by an English maLn perfecuricauai^rH^ w^^^ l""^ "^ ^" ^"^ ^^^^"e"t manner, retorts, who was sent over on'^urS^^^^^ '"^^^^ ^T'i"? ^oal-ga^ similar to that represented VfiTTio Dale R47 Jw r^K*"^ ''"^^^ ^' P''^^^^^^^^ immersed in a bath of uniformly if;it«i'arwh^I^^^^^ uppermost retort is top, pla, round the two ^n.eL^^^f.o^^C^l^ Z7Ttr;^^^^ MERCURY. 189 them. The bottom of the uppermost retort is protected from the direct impulse of the flame by fire-tiles. The dotted lines k k, show the paths of the chimneys which rise at the back ends of the retorts. In the section, Jig. 901, a is the body of the retort ; its mouth at the right hand end is shut, as usual, by a luted iron lid, secured with a cross-bar and screw-bolts ; its other end is prolonged by a sloping pipe of cast iron, 4 inches in diameter, furnished with a nozzle hole at l, closed with a screw plug. Through this hole a wire rammer may be introduced, to ascertain that the tube is pervious, and to cleanse it from the mer- curial soot, when thought necessary, c, is a cross section of the main condenser, shown in a longitudinal section at c c, Jig. 902. This pipe is 18 inches in diameter, and ^bout 20 feet long. At a a, &,c., the back ends of the retorts are seen, with the slanting tubes 6 6, &c., descending through orifices in the upper surface of the con- denser pipe, and dipping their ends just below the water-line h i. g, is the cap of a water valve, which removes all risk from sudden expansion or condensation. The condenser is placed within a rectangular trough, made either of wood or stone, through which a sufficient stream of water passes to keep it perfectly cool, and repress every trace of mercurial vapor, and it is laid with a slight inclination from i to A, so that the condensed quicksilver may spontaneously flow along its bottom, and pass through the vertical tube d into the locked up iron chest, or magazine e. This tube d is from the beginning closed at bottom, by immersion in a shallow iron cup, always filled with mer- cury, fe is a graduated gauge rod, to indicate the progressive accumulation of quicksilver in the chest, without being under the necessity of unlocking it. This air-tisht apparatus was erected about a year ago, and has been found to act perfectly well ; I regret, however, that my professional engagements at home have not hitherto permitted me to conduct its operations personally for some days. The average samples of cinnabar ore from Obermoschel are ten times poorer than those of Almaden. Were such an apparatus as the above, with some slight modifications which have lately occurred to me, mounted for the Spanish mines, I am confident that their produce in quicksilver might be nearly doubled, with a vast economy of fuel, labor, and human life. The whole cost of the 9 large retorts, with their condensing apparatus, iron magazine, &c., was verv little more than tv^o hundred pounds ! As the retorts are kept in a state of nearly uniform ignition, like those of the gas works; neither they nor the furnaces are liable to be injured in their joints by the alternate contractions and expansions, which they would inevitably sufler if allowed to cool ; and being always ready heated to the proper pitch for decomposing the mercurial ores, they are capable of working oft' a charge, under skilful management, in the course of 3 hours. Thus, in 24 hours, with a relay of laborers, 8 charges of at least 5 cwts. of ore each, mi<'ht be smelted =2 tons, with 3 retorts, and 6 tons with 9 retorts ; with a daily proluct from the rich ores of Almaden, or even Idria, of from 12 cwts. to 20 cwts. Instead of 3 benches of 3 retorts each, I would recommend 15 benches, containing 45 retorts, to be erected for either the Almaden or Idria mines ; which, while they would smelt all their ores, could be got for a sum not much exceeding 1000/., an outlay which thev would reimburse within a month or two. . . ^ j.x. • i ThrfoUowing letter from Dr. Tobin gives an interesting account of the me/curial mines In California. I ' il 140 MERCURY. That part of California where I have been residing, and that which I have just visited, consists of three long ranges of trapp mountains, with two wide valleys dividing them, the valley of the Saa Joaqum, and the valley of Santa Clara. Near this last place are the quicksilver mines of New Almaden, where I have been working. The matrix of the cinnabar ore is the same trapp of which the mountain ranges are composed, and as yet only one great deposit of this ore has been found, though traces of quicksilver ores have been discovered m other places. The ores are composed solely of sulphuret of mercury (averaging 36 per cent^ red oxide of iron and silica; and had the mine been properly worked from the commencement almost any quantity of ore might be extracted • it now however, more resembles a gigantic rabbit warren than a mine. The owners have lately sent out an old German miner, an expeiienced and practical man, who, if he stavs here, will eventually put it into some kind of order. Its greatest depth is about 150 feet, and the weekly extraction of ores varies from 100 to 150 tons. Upon arriving here I found the concern in such a state of disorganization, that, after waiting three months in vain, and not having received a single cylinder or piece of machinery, I returned to Mexico to tetch up one of the proprietors. During my absence the former director, who in his lile had never seen a mine, much less smelting works, put up four of the cylinders, sup- porting them solely upon their two ends without any'fire-brick guards or pillars. Of course, when heated they sunk or sagged in the middle. Upon my return with one of the ownere, something like order was established by him, and I got 16 cylinders at work, producing 1400 to 1500 lbs. daily. The result to me was satisfactorv. but not so to the proprietor, on account of the expense of fuel and labor; he accordingly got a blacksmith, who had been sent here to jput up the water-wheel, to build him a small furnace, without consulting me at all. This man sent a friend of his, not liking to come himself; to look at the plans I had of the furnaces of Idria and Almaden, and then erected a snaall and miserable furnace to hold one ton of ore, upon a disimproved plan of those of Idna. With this he obtained from the richest ores (66 to 72 per cent) 38 per cent of mercury, of course with the consumption of very little wood and with little labor; (the loss of per centage was not thought about!) The proprietor immediately determined to have six similar furnaces built and with great regret allowed me to erect one good furnace, and afterwards a second one. « Now take the results of the year's work, and you can judge whether the report sent you if i/^ ^f ?^*' • ^^ ^^a^kee blacksmith has superseded me or not Before the year was out, he got tired of attempting to compete with my furnaces, and left in disgust The cylinders produced (but were stopped in November on account of expense of working) The first furnace, working only from November 1st to July Ist, 1851, gave - - - . . The second furnace, working only from March 18th to July Ist, gave - - - . . - 261,616 lbs. Mercury 620,613 888,825 _- , Total 1,255,954 "The product of the Yankee's six furnaces, working for a much longer period as they went mto operation long before mine, was only 644,000 lbs., making a total pro- duct for the year of about 18,000 quintals." ^ Quicksilver is a substance of paramount value to science. Its great density and its regular rate of expansion and contraction by increase and diminution of temperature give it the preference over aU liquids for filling barometric and thermometric tubes. In chemistry it furnishes the only means of collecting and manipulating, in the pneumatic trough, such gaseous bodies as are condensible over water. To its aid, in this respect the modern advancement of chemical discovery is pre-eminently due. This metal alloyed with tin-foil forms the reflecting surface of looking-glasses and by its ready solution of gold or silver, and subsequent dissipation by a moderate heat It becomes the great instrument of the arts of gilding and silvering copper and brass The same property makes it so available in extracting these precious metals from their ores^ The anatomist applies it elegantly to distend and display the minuter vessels of the lymphatic systeu^ and secretory systems, by injecting it with a syringe through all their convolutions. It is the basis of many very powerful medicines, at present proba- bly too indiscriminately used, to the great detriment of English society- for it is far more sparingly prescribed by practitioners upon the continent of Europe, not other- wise superior in skill or science to those of Great Britain. The nitrate of mercury is employed for the secretage of rabbit and hare-skins, that is, for communicating to fur of these and other quadrupeds the faculty of felting which they do not naturally possess. With this view the solution of that salt is applied to them lightly m one direction with a sponge. A compound amalgam of zinc and tin is probably the best exciter which can be applied to the cushions of electrical machines. METALLIC FUMES. 141 The only mercurial compounds which are extensively used in the arts, are factitious cirab^Jr Vermilion, and corrosive sublimate. Quantity imported for home con- sumption in 1860, 355.019 pounds ; in 1851, 27,370 pounds. , • t^ • o f^wn A large quantity of mercury or quicksilver is annually produced in Idria, a town inthe dlci?yof Carniola, the InhalJitants of which are chiefiy occupied m its extrac- t^^on The%uicksilver mines are extremely productive, the cmnabar ore yields when very rlX 60 per cent of this metal This ore is a sulphuret of mercury, and ffives UP the latter metal by sublimation. ^ With the quicksilver mines of Idrla is connected a manufactory of vermilion, which produced, in\he year 1847, 981 cwt of that pigment The residue of the q^ic^s^lvei is used up to some small extent, about 300 cwt, for technical purposes and prepara- t ons ; but the greater portion of it is sent abroad. The exports of q«^eks^lJeJ amounted to an annual ^vera^e of 2,341 cwt (in the year 1846 they reached 6,478 cwt), and of preparations denved from it, such as corrosive subhmate, calomel, Ac., to 41 cwt By the consumption of quicksilver, for the manufacture of vermilion and for other technical purposes, the value of the annual produce of the raw material is greatly increased. The mines have been worked for upwards of three centuries and a Imlf and were oricinallv discovered by an accident , , , «_ MFRCURY BICHLORIDE OF; Corrosive sublimate (DeuiochJarure de mercure, Fr. ; Jetzendes quecksilber sublimat, Germ.), is made by subliming a mixture of equal parts of » persSphate of mercury, prepared as above described, and sea-sa t, m a stoneware cucur. bit The sublimate riles invapor, and incrusts the globular glass capital with a white mais of small prismatic needles. Its specific gravity is 5- 14. Its taste is acrid, stypto- SSallic, and exceedingly unpleasant. It is soluble in 20 parts of water, at the ordinary Smpe a ure, and in its own weight of boiling water. It dissolves m 2^ times its weight of cold alcohol. It is a very deadly poison. Raw white of egg swallowed »« jf^s^o". is the best antidote. A solution of corrosive sublimate has been long empMed for pre- "ervin? soft anatomical preparations. By this means the corpse of Colonel Morland was eSmed in order to be brought from the seat of war to P^is. His features remained unaltered, only his skin was brown, and his body was so hard as to sound hke a piece of wood when struck with a hammer. _ In the valuable work upon the dry rot, published by Mr. Knowles, secretary of the •ommittee of inspectors of the navy, in 1821, corrosive sublimate is enumerated among the chemical substances which had been prescribed for preventing the dry rot m timber; and it is weU known that Sir H. Davy had, several years before that date, us«I and recommended to the Admiralty and Navy Board, corrosive sublimate as an anti-dry rot application. It has been since extensively employed by a jomt-stock company tor ine same purpose, under the title of Kyan's patent. , . . t^, MERCURY, PROTOCHLORIDE OF; Calomel; (Protochlorure de ^"^^'^yJ/'\ Versiisstes quecksilber, Germ.) This compound, so much used and abused by medical practitioners, is commonly prepared by triturating four parts of corrosive subhmate along with three parts of running quicksUver in a marble mortar, tiU the metallic globules entirely disappear, with the production of a black powder, which is to be put into a glass baUoon, and exposed to a subliming heat in a sand bath. The calomel, ^^ich rises m vapor, and attaches itself in a crystalline crust to the upper hemisphere of the balloon, is to be detached, reduced to a fine powder, or levigated and elutriated. 200 lbs. of mer- cury yield 236 of calomel and 272 of corrosive sublimate. . , rr i, The following more economical process is that adopted at the Apothecaries Hall, London 140 pounds of concentrated sulphuric acid are boiled in a cast iron pot upoa 100 pounds of mercury, till a dry persulphate is obtained. Of this salt, 124 pounds are triturated with 81 pounds of mercury, tQl the globules disappear, and till a protosolphate be formed. This is to be intimately mixed with 68 pounds of sea-salt, and the mixti^ being put into a large stone-ware cucurbit, is to be submitted to a subliming heat. See ^ Fm^l90 to 200 pounds of calomel rise in a crystalUne cak^ as in the former pro- cess, into the capital; while sulphate of soda remains at ^^^bottom of the alembic. The calomel must be ground to un impalpable powder and elutriated. The vapory instead of being condensed into a cake within the top of the globe or in a capital, may be allowed to diffuse themselves into a close vessel, containing water in a state of ebulli tion whereby the calomel is obtained at once in the form of a washed impalpable powder Calomel is tasteless and insoluble in water. Its specific gravity is 7 176. For the compound of mercury with fulminic acid, see Fulmlnate. PmW«fe of tnercurv is a bright but fugitive red pigment It is easily prepared by droppmg a so- lution of iodide of potassium into a solution of corrosive sublimate, as long as any pre- cipitation takes place, decanting off the supernatant muriate of potash, washing and ^'fe'i^'v^'S'iS'/or, b, Mr. Morgan of Dublin. If a strong solution of iodide of poSi^ beaded to i iinute portion of any of the salts of mercury, placed on a 142 METALLIC STATISTICS. lea^tTolor:^^^^^ detecte<^ although the mixture with s^arTnot i^Te least colored by it. With the preparations of mercury in the undiluted state thi« process acts with remarkable accuracy, the smallest quintity of caS or peroxide placed on copper as above, will give with iodide of potassium a distinS metaUic stli^ Mr Morgan supposes that the iodide of potassium forms a soluble salt wiTh the seveS MFTaTtIp ^i^ decomposed.-PA. Journ,, Feb. 1852. '^""^^ METALLIC ANALYSIS. Professor Liebig has lately enriched this moaf «««f„l tT'^r' ^' ^'^''''^^ chemistry, by the e^plojnnent VthTcyi d"^^^^^^ ^IZT^ '° V 'i ?««"r/"^^ J^'^^""^ («^^ *^'« ^^^i«l«)- Th'« ««lt is the best regent fo^ fal^K "^^"/^'^ m cobalt The solution of the two metals being acidulated, the cyanide s ttn?ddef a?d' thl^' ^^ P^If'" '^'' ^''^^^^"V« redissolvel Dilute sulphurS f«n t« ' ^ ^^^ mixture being warmed and left in repose, a precipitate does nc« fail to appear sooner or later, which is a compound of nickel Cvanide of nntn«Jnm eadTnd Sl^fth f?ii ^""1!^^ '"^ ^^"'J' '° ^^^ '^'"^'"'^ of these metals in nitric acid, add SulnrrPtti vh' '^•^^°'?^^^^' ^1^. °^^y be parted from each other by sulphuric acid, bulphuretted hydrogen is passed m excess through the residuary solution and the mixture being heated, a small quantity of cyanide is added : TyelWpred^^^ ^pp" hfpTrni;"' ' '^"' ^"^^^^^^^^ '^"^ ^'^ ^^^ ^'^^^^-^ of CrocSfoTaSd/tf 'A K^^lu * ^^"^^b.^« (containing the cyanide fused by heat), a little of anv metallic ox WhJn t'T"^?' intervals, it will be almost immediately reduced to the rL^^^^^^^ whiLsdinfmltTerfrl'w^^^^^^ decanted, the metal'will be found mTxId^Uh the wmie sajine matter, from which it may be separated by water. in «1t;?tf Ti '"^p5"^^.^« *^^ 'Educed to the state of pure metals by bein- proiected LIL.,?^ ^"k" ^'''^^''. *"*^ ^^"^ ^"«^^ ^y'^^i'le- When an iron ore is thus hu/^ucS^ alTrl ^^ carbonate of potash or soda, and the mixture is heated to fusbnwS^^ quires a strong red heat, the alumina and silica of the ore fuse into a s as from w hi^r l7mTn'a^Se feS:;tlh;^r^^ separated by the action o^^er^, :L^d^'hen:eTgS "separate nroce. w\l^ '} T^'"' "" ^^^ '*^*^ of protoxide ; to be determined by T,l^'r%Z7:t C/r'tLlTettra'"""^''^' '' •" "^ ''-' and 1 J^^X^ bei^^\cSSifhedlT» w P«"«"lr iM"«'>n? with the oxide of antimony and tin ; oem, accomplished at a low red heat, hardly visible in daylight. Even the sulDhnrrti cyanS: or;:!t\:sTur^'^^^^^^ ^^"^^^^ ^^^^^'^ -^^^-^ -^^^ ^^^ fo^at^oro^ft^rpr Pb^onlratlrfor 'i^ r' ""^t^ "^'^^ '^'i^^"^^^ °^ «^^' ^' °» ^^^^"ent re-agent in blow- facmtv In^^L f(,if "^T^'"§ ""^'^^'* "^^^ reductions take place with the utmoTt Sone is ant to do ?n such'clr ^V ""' T^ '"^" '^' charcoal, as carbonate of 3a :nd"Ln ^'beVe'r exrined."" "'"^'^ ''*^ ^^^^"^ °^ ^^^^« «^ ^^'^' «- -°- visible. When the cyanide is heated along with the nitrates and chlorates (of notash^ it ran«*.. a rapid decomposition, accompanied with light and explosions ^ Potash), it causes :t t-.fh'T ^"7 ^l^^^fy detected in the commercial sulphuret of antimony by fusing tZ V^^' ^''"'^';' °^'*' ^-^'^^^ °^ ^^^ ^y«"ide in a porcelain crucibTe over a sn rk lamp when a regulus of ant mony is obtained. The metal may then be elsily tes ed th^JJ^^^oT^^^r^Il^ ''*'^^' "'■ orpiment, or any of the arseniates, are mixed with six tim*., their weight of the mixture of cyanide and carbonate of soda in ^tuhewiih a bu b^at the sihca gets combined with the alkali into a soluble glass "''"'^^ * carbonate, and METALLIC FUMES (CONDENSTATION OF), 6y Ih/iuke of JBncdeugh.-ln all great smelting works of lead and copper, the smoke rising from the furna^s is hiehlv charged with the most noxiou. va|.oi-s, containing, besides other poisonous mattSr a METALLIC STATISTICS. 143 laree quantity of lead. Many attempts have been made to obviate this nuisance . and the system al by the exhibitor has been found to be very successful l/oblong building^in solid masonry, about 30 feet in height is divided by a part - tionwalinL two chambers, having a tall chimney or tower adjoining, whicli commu- mcatls wilh onlof the chambers at the bottom. The smoke from the various furnaces, e^htTnTumber and about 100 yards distance from the condenser, is carried by separ- Tte flJes iTo a large chamber; from thence by a larger flue it enters the first chamber of the condenser at the very bittom, and is forced upwards in a zigzag course towards SetoD Sne four times through a shower of water constantly percolating from a Irced reXoir at the summit of the tower. The smoke is again co^Pfll^^/^ fi^^^;. rfifthtfme through a cube of coke, some 2 feet square, through which a stream of water fiS downlards, and which is confined to its proper limits by a vertical grat- J^g of wood TTieTmoke having reached the top, is now opposite the passage into the second or vacuum chamber. , • , k r^^f k,t ^J foof ina?-^^^^^^^ ''%^7^::^^s'^T.n'i^^'iT^^'''>^e^^ - cuiiousand instraetive At the r.;„LT„ Stream Works, north of Falmouth, the rounded pebbles of tin are found at Xthla^^SOfTetfrL the surface, beneath the bottomof an cstua^^^^ Le Covered in their places of growth, t-^e^er with tam.m s^^^^^^^ of deer amidst the vegetable accumulations which immediately "»*«' "■«"", . ,„ Iwdf A^ordine to Mr. Kenwood's measurement the section presents first about 50 ^t of siH and gravel; then a bed of 18 inches in thickness of wood, leaves, nnt^ *«•. ^ting on fhe tfrgroind. composed of the debris of quartz, slate, and granite, a^d the 144 MEATALLIC STATISTICS. tin ore. At the Pentuan "Works, near St Austell, similar deposits occur, proving a material alteration in the level during the period expended in the formation of this de- posit Tin is also worked out of the lode in many parts, the ore occurring both in the slate and the granite formations. The modes of dressing the tin ore, preparing it for the smelter, and the process of smelting, are illustrated in the Exhibition. There has been a remarkable uniformity in the quantity of tin produced in Cornwall during a long period, as will be seen from the following table : — Years. Tons. Price per cwt & & 1760 1,600 1760 1,800 1770 2,000 1780 1,800 8 1790 2,000 8 15 1800 1,500 6 1810 1,400 7 1820 1,700 3 5 1830 3,500 3 1840 5,000 3 15 The produce of this metal within the last few years has been as follows :— Years. Tons. 1844 7,607 1845 7,739 1846 8,945 1847 10,072 1848 10,176 1849 10,719 The produce of zinc is not easily attainable, but it is now somewhat considerable, as is also that of arsenic, and of the iron pyrites, used in the manufacture of sulphuric acid- The number of individuals employed in 59 Cornish copper mines was computed by Sir Charles Lemon in 1837, to be — Men - - - 10,624 Women - - - 3,802 Children - • - 3,490 The men alone work underground ; the women and children are employed on the Bur&ce picking and dressing the ore. Mr. W. Henwood estimates the number employed at — Men - - - 18,472 Women - - - 5,764 Children - - - 5,764 80,000 Tin appears to have been raised in Cornwall from a very early period. Traditionary evidence, supported by strong corroborative facts, appears to prove that the kingdoms around the Mediterranean Sea were supplied with tin from Cornwall by the Phoenician merchants at a very early date. The circumstance of this metal being found in the beds of streams, and in deposits at the base of the primary rocks, from which it could be obtained without much labor, may have been the cause of its being early known to the Britons. The oxide of tin is usually found deposited in beds in water-worn pebbles, and mixed with the debi-is of the neighboring hills. There can be but little doubt that these tin deposits are the result of the disintegrating action of the atmospheric causes and of water. Some of the tin beds, 30 or 60 feet from the present surface, contain vegetable matter, as branches of trees and lai^e logs of wood ; and at Carnon Stream Works, human skulls were discovered amidst the debris, 63 feet below the surface. Tin is also found in the lode, either as peroxide, cupreous-sulphuret of tin, or tin pyrites, the analysis of the peroxide giving peroxide of tin, 96-265 ; silica, 0-750; peroxide of iron and manganese, 3-395. Many indications of early tin-mining are to be found in Cornwall, as stated in pre- ceding note. For many centuries the Duke of Cornwall drew a large revenue from ita tin. The tin, when smelted into blocks, was forwarded to the nearest coinage town, there to be stamped by the duchy oflScers, who cut a piece of the comer of each block, which was retained as the duchy''s dues. In 1337, Edward the Black Prince was cre- ated Duke of Cornwall, and then the average profit of the coinage was 4,000 markii METALLIC STATISTICS. 145 per annum. In 1814, the revenues to the duchy from tin was about 8,600/., and the average tin revenue from 1820 to the abolition of the coinages in October, 1838, haa been estimated at 12,000/. per annum. In 1760, about 2,000 tons of tin were producer in Cornwall, and in 1838, about 5,000. Since that period the quantity can be accu- rately ascertained, the trade in tin being in the hands of a few, and the purchases of ore being usually made by private contract By the returns to five several orders made by the House of Commons, which were obtained by the exertions and perseverance of Sir J. J. Guest Sir C. Lemon, aod Mr. Evans (M. P. for North DerbyshireX ^^ are enabled to lay before our readers a moet correct accountof the various exports and imports of iron and iron ore, hardware, cutlery, Ac, copper ore, tin, zinc, lead ore, and lead, for the year ending Jan. 6, 1844. Commencing with iron, it appears there was imported in tlie year^ iron ore, 131 tons; chromate of iron, 1393 tons; pig-iron, 243 tons; unwrought iron in bara, 12,795 tons; bloom, 663 tons; rod-iron, 12 tons; old, broken, and cast-iron, 286 tons; cast-iron, only 8 tons; steel, unwrought, 1697 tons— of these, 97 tons only were entered by weight the remainder by value, 11036/. 6«. 9 CO o CO « P « ^ 5 C 13 eS O * 2 « « « c, « ^ e ? c s 6 o o o o « » «= £ 2 Sd^ O C CDaOQOb-b>i to 5 9 8 •jaddoo JO nox « 9]{«UI O) 9JQ U^I^ -aoo JO 9ni«A eswa^v •jaddoo JO uox « oifvui (X) 9J0 JO ''()!4(renb eq) JO ani«^ 9:^9Ay •Xauopi nj oioqM. am JO oui«A WOi •jaddoQ am J uj aioqj*. oqj joaonpoij [wjox •^anopi * CO o> oo» «0> ' ^4 r-^ a«^ ud ^"^ ^T" wi-/ ^^ -•^ >»• ^^ ^2 J CO o> o o» <» » o «'j.'^1''5,''i.''l®-'^^^ \ ea aa Si OD ^ t^ ■^ —• oo >fl !?j o ct> «0 O '^ JO n OD < CO 01 3 3 T-l 00 00 00 00 o CO 00 to to 00 Ok lu lad aonpoid aSwaAy «D4P ^<0 CO JO saox u\ 9J0 JO oco^«- CO -^ ?o CO 00 00 00 00 •eunp q?08 I I I S s a> o ^> t-i o Cm « o ^ CO flf *^ © ;;; ^ ee o S u a S CO g METALLIC STATISTICS. [181] .S « •6 ^ CO S 8 S O 3 s. «3 a I 3 o a &0 s. « .9 • a. ^1 -<$ CD Ok CD IO to 00 ao a o o 00 S TH 5 TH CO Oft o CO E m 1 1 1 s E s i*^ c ^ 00 U 00 •^ e •44 « .T< «« s s § -a -a -5 00 00 OQ ^ a St 00 .S cS 4> at (B go 00 ^ ct I i E ^ cS 00 •a "3 ID OQ -a o •»" at « « en 00 a CS 00 ^ i E S O at o "S •> O (D OQ s 8 a 9 I 4 a a o B < > < CO 3 S / ■■' !■ ill [132] m to at « « o > §•« OB ^ « « 9 fe O 00 "^ •>H CD , g^ cd" eC of r^ t-T i-T a # * «o Ok ^ O ^ ^ P 00 ». m 1^ 04 . _ ^ o» aS qS' tS t^ i^ 3 to § p r1 »- i-( c» e* $ 00- »4 ^ ^ A t-^ t>^ _ g. :f :f ^ orf- ^ e© g »H r1 »-» r^ rH r^ i s s s I: '" 6 s s id- Eh S S S S ^ f „ Ok 00 A rH OQ O S ^ 00" 00- etf ^ otf- g Tt n »-l rH r1 *-• 8 I I I I v-« s g s '^ i d fe 5 § 1 j4 1^ o >■ H < 3 OD 3 S S S [138] i: t ! [134] METALLIC STATISTICS. METALLIC STATISTICS. [186] ■t • iSS. V. S< o,'? 2 '-" m 00 9 g 6l •P "SC OD S§: ^ ia lo o to O t- X S* tH »-1 T^ fH 7? S^ a S e»» s s s s s s t- a S r1 "2 3 •e 00 IH to fH fH - 5 . i£; ! a. <^^ .d •s? S 5 3 g o ■s*» fH 00 t- o« 00 -d ie ^ t s a' oT IH §" ^ ^ fH . .J" •fl •O O •5 . a ^^ ^ 1^ 2Ls ? ^ 9 S5 ? 1H '1 00 Ok 0« 04 s s iS »H 00 g. •< a 2 -^ o Sp ^1 1 o o" 1 s OS- '*- o 3 fH O « s TS 8. • •g OS "►Jj" ^ i IS §s ^ 00 o of otT f-J, h* »-« T-l tH t-« *- Pt 5 1 1 1 3 S S o >* T-l fH r-l 1-i fH H 00 eo GO £ « « Ed « •a <) of 3 O o o CO .2 •-3 a a it 5' 3 ss, ii N It r o > 1 I 6 I ^111 1^ o o o o o «i lO lO O lO o fH fH tH ^ 8 ss S S S s a» o eo «4 on OB 0» fH lO O fH 8' t: a • •^ «P »H b^ O 00 00 04 fH S" 5! S ? 9 2 O 00 <0 K) CO ' •"S ^ 5^ •f tH fH fH fH fH « t» ■SS, (il rH fH fH fH fH i^ 5^ « a" jO c 'ft if a li S o •«l • fH fH »• 04 O o ^8 *6 fH ^ ^ «o "* 00 to 5^ *H O • S o o O Cti r .d ts i> •c ».• (^ fH fH s 3 S s w X is fH ff of o ^ tS c 88 es ■s . • p^ - o 15 l<5 t b iS • ll § $ ? s ? -< P o» o» S S S 6 • g < «G *« V *% 1 P -i s 1' • S >o 8 '^ fH 00 to t- s « ^& *» fH of o il ;S fcl « cx< ■« a, o & eo 1 s s § lH rH ca 1 fH « 1 1 i fH fH i fH fH fH ^ a 00 eo CO f-H £ «9 • rH O ,£3 o to a « • pH a a ft e: ,a « u O »H CI. o 00 ca 08 9 3 IS. C a. « a |l is I- It (2 o > e E a^ •9 J- .» I I i II 1^ o o o o o W >o lo o o o fH fH »H «^ s s s s s S8 1^ »• o o >e 00 « O H|i o o« o fH ^ Kd lO lO lO h8i to ^5 5? 00 ^ o? fH * 00 lO o o ''I fH fH fH r^ «a I i I i I ^ e' 2 ;^ s' 00 00 Oi ©» S2 S S 2J S - 1(3 ^ p> op ^ S th s s ot . 't © e« rH gS >Q 0> b> 0» . . 00 iO rH H ;^ S' S g §' fH 3 do oo aa m OD I / [136] METAIXIO STATISTICS. METALLIC STATISTICS. [187] ill Imports of Foreign Copper and Copper Ore into the United Kingdom from 1882 to 1849, inclusiye. FRANCE. 1^ ' 1882 1838 1894 188& 1886 1887 1888 1839 1840 1841 1842 1848 1844 1845 1846 1847 1848 1849 Copper nnwrought. Part r rough t. T. ctqr. lb. T. ct qr. lb. 2 — 2 15 — 12 4 1000 01 21 10 1 1 23 21 18 1 15 — 94 14 0289 714 PlaUMud Coin. I 51' 1884 9 8 15 1885 — 1886 21 188T 1888 *^ 188d __ 1840 •..• 1841 -_ 1842 ... 1848 ._ 1844 — 1845 — 1846 __ 1847 ^— 1848 19 184 — 2 2 8 19 1 8 11 8 2 8 11 8 8 8 7 2 8 2 14 15 5 2 28 18 7 6 2 23 18 10 9 18S8 1884 1886 1886 1887 13 1888 41 1880 1840 4 iML 1848 1848 1844 1845 1846 1847 1848 1848 18 1 15' 5 8 1 19 23 8 20 8 11 2 14 1 26 9 T. 6 ct qr. lb. 2 2 1 22 10 1 11 1 2 1 i 8 14 15 4 1 14 5 14 2 14 2 8 OU for remaaofiM- ture. T. ct 8 qr. lb. 25 2 7 2 2 13 13 2 9 18 8 12 8 14 1 5 2 20 1 4 Or«. T. Ct qr. lb 1 25 9 a 1 14 12 2 1 19 8 15 118 4 32 4 45 6 12 Copper maoufactarea. Weight. I Value. 6 8 4 1 18 2 2 T. ct qr.lb. £ — 2,268 — 2,888 2,845 1,555 2,287 — , 6,914 — ! 1,601 6 2,548 1,897 1,780 1,451 1,986 2,788 2,818 2,891 8,069 2,841 2,704 n d. 6 18 6 2 10 6 4 1 15 10 114 16 16 18 19 14 8 6 6 6 6 4 10 18 11 19 2 2 7 10 18 GERMANY. 18 c 8 14 1 22 14 8 18 17 18 8 6 1 25 7 8 12 8 8 10 2 7 2 18 10 1 8 9 4 2 5 2 1 19 8 2 12 2 10 8 5 8 19 2 14 8 17 2 6 20 8 21 10 12 11 18 14 8 24 2 25 8 6 8 2 125 8 2 25 19 18 27 83 10 5 28 12 1 4 19 2 6 4 8 15 10 17 28 18 12 14 5 8 6 6 10 15 11 14 24 8 8 1 20 2 22 2 19 1 7 21 8 20 2 1 16 1 17 2 21 2 24 ITALY. S 1 88 80 — 1 7 8 80 2 16 8 1 1 5 1 28 8 8 14 8 7 1 20 16 11 2 2 1 8 6 17 22 4 19 80 19 12 102 18 1 14 245 10 24 824 9 1 4 865 17 8 24; 2 14 17 8 1 84 558 10 8 8 14 2 8 « «■" « J^ ^1 2 14| 1 19 1 11 3 8 576 16 2 2 1 6 8 11 8 16 207 2 8 8 1 18 1 18123 8 3 6 10 8 6 1 18 1,518 2,161 2,903 2,061 1,211 1,866 818 827 249 667 101 204 295 402 520 l,ltt 4 6 2 4 2 4 10 19 5 18 8 12 2 6 11 7 6 6 6 4 6 11 7 8 6 9 1 24 18 8 18 18 1 19 28 8 159 10 10 58 12 87 180 68 6 6 1 Imports of Foreign Copper and Copper Ore — eoniinued. RUSSIA Year t C^per MaaofiMtoree. emling Jan. 5. Copp*r nnwrought. Part wrought. Plates and Old, for r«ma- Coin, nufactare. Ore. Weight Value. T. ct qr. lb. T. ct qr. lb. T. ct qr. lb. T. ct qr. lb. T. ct qr. lb. T. ct qr. IK £ «. dL 1882 — — _ , 8 12 — — — 1888 ^.v .^K — — ^ 1884 5 18 9 5 18 — — 1885 5 1 23 26 19 1 18 ^ — — — 7 10 1886 9 12 4 16 1 1 14 — — — — 41 15 1837 8 22 -_ — 8 1 11 — 4 1888 __ _ 8 20 — — 5 1839 — ^ ^ 118 6 — — — 1840 _ — ^_ 8 28 — — ^.^ 1841 — — ^_ — — — 8 1842 ._ —. __ — ^ — 82 1848 ^. ^^ ^^ 2 24 — — 46 15 6 1844 8 4 18 ^^ 1 18 7 — 17 16 2 17 1845 ^ _ _ ^ 96 15 1846 ._ _ 1 6 8 14 — — 1 12 2 16 62 10 1847 32 2 8 2 _ __ 12 8 4 — — 8 1848 _ ... 10 — — 14 15 1849 — __ 8 on 1 24 — """ 8 10 HOLLANTD. 1884 1886 ia36 1887 1888 1889 1840 1841 1842 1848 1844 1845 1846 1847 184S 1849 7 17 8 16 1 14 8 7 1 812 1 12 16 1 8 28 1 028 1 18 2 25 4 7 014 0*2 2 1 8 21 8 43 18 20 57 8 85 16 88 50 _ 40 6 ^_ 90 1 ^M 13 5 2 ..^ 63 18 2 14 _ 89 16 325 — 110 5 3 11 13 2 9 2 12 8 8 1 76 10 19 8 16 10 10 1 9 4 5 23 8 9 2 10 18 1 NORWAY. 1S85 8 15 116 5 2 10 1886 __ „^ M^ _— 507 11 18 1887 — . __ __ — 182 17 1 16 1838 — ^_ _. ^~* — 1839 — _— — — 1840 _ .^ ^^ 4 2 17 — 1841 ^ _ 78 17 11 — 57 8 2 14 1842 — ^_ .— 118 125 - 1843 79 9 1 10 — 60 10 6 «. 89 6 1 1844 — 45 14 8 22 28 12 1 2 «» 5 10 1 20 1845 140 5 8 6 — .1. ^^ 8 18 1 9 1846 69 9 2 18 — MM «M. 4 7 221 1847 69 19 4 -. «. 1848 82 17 8 27 — __ 2 19 10 1849 — 62 12 8 11 — — — 23 17 83 2 15 27 32 12 14 10 8 25 2 28 16 13 20 8 18 2 5 8 6 15 8 8 10 8 8 1 69 72 24 59 100 65 512 288 114 296 670 1,088 821 8,948 10 1 6 19 6 5 i 8 8 ) 6 10 6 15 17 1 12 6 884 10 I / I ri38] METAT.TJO STATISTICS. Quarterly Sales of Copper Ores in Cornwall for the Six Years ending the Slat of December, 1849. Qaarter ending March 31, 1844, . . . . „ June 30, 1844, „ September 30, 1844, « December 31, 1844, . Total,. Quarter ending March 31, 1845, „ June 80, 1845, .... n September 30, 1845, n December 31, 1845,. Total,. Qaarter ending March 31, 1846, .... „ JuneSO, 1846, „ September 30, 1S46, „ December 31, 1846, Total,. Quarter ending March 81, 1847, .... June3i>, 1847 September 30, 1847, December 81, 1S47, w M Total, Quarter ending March 81, 1848, , „ Jnne80,1848, , „ September 80, 1848, , „ December 81, 1848, Total,. Quarter ending March 81, 1849, . . . . „ JuneSO, 1849 „ September 30, 1849, u December 81, 1849,. Total,. ToQflL 89,874 87,806 88,078 87,716 152,969 40,367 49,834 42,420 88,926 162,557 39,835 82,282 87,784 85,079 144,480 88,071 84,875 40,174 40,000 153,120 85,532 87,905 86,287 85,972 147,701 86,093 86,681 87,108 86,508 146,335 £ a. a. 219,019 8 188,721 8 195,626 17 6 198,066 16 801,484 4 ft 215,284 8 226,878 8 250,257 1 6 228,019 18 6 919,934 6 9 207,697 10 200,810 11 6 196,486 16 191,197 9 796,192 6 ft 222,543 9 204,662 4 6 229,969 2 6 216,263 14 878,486 10 202,517 9 176,880 17 164,409 10 6 176,888 6 720,090 17 188,507 ft 187,167 15 6 194,495 11 ft 198,444 11 ft 763,614 19 Quarterly Sales of Copper Ores in Cornwall for the Year 1849. Quarter ending. Ore in Toni of 21 CwU Fine Copper. Amoont of Money. ATorage per Cent. ATerai^e Standard. Per Too. March 81, Jane 80, 86,093 86,631 87,108 86,508 2,981 11 2,906 14 2,992 17 2,810 2 £ 8. d. 188,507 6 187,167 15 6 194,495 11 6 198,444 11 6 8i 7» £ 9. d. 98 12 98 16 2 97 14 1 104 10 11 £ 9.d. 5 4 5 5 2 2 5 4 10 5 5 7 September 80, .... December 81, Total, 146,835 11,691 4 763,614 19 8 99 18 8 6 4 8 METALLIC STATISTICS. Importfl of Foreign Copper and Copper Ore^ Continued. SWEDEN. [139] Year ending Jan. 5. 1832 18:33 1834 1885 ias6 1837 1883 1839 1840 1841 1842 1843" 1844 1845 1846 1847 1843 1849 CJopper on wrought T. ct. qr. lb Part wrought T. Ct qr.lb. 1 17 Plates and Coin. Old for Ee- manu&ctnre. T. ct qr. lb. T. ct qr.lb, Oro. 11 14 2 11 45 7 . 8 21 277 11 2 8 191 18 I 14 126 6 8 55 11 2 21 2 6 3 16 1 19 8 27 Ck>pper Manulkctnres. Weight T. ct qr. lb 714 14 866 6 82 789 18 2 9 685 8 10 498 9 26 1905 « 8 18 1 16 2 8 1469 10 ,0 718 15 2 11 501 18 28 10 16 12 14 6 18 T. ct ^r. lb. Value. 10 9. d. T 824 2 6 5 SUMMARY. Imports of Copper and Copper Ore from the whole of Europe into the United Kingdom, from 1832 to the 6th of January, 1849. Copper nn- wrouebt ID Bricki or PiKi, Ro«e Copper and Catt Copper. Part wroujfht Bars, Rods or In- ^tt, hammered or raised. Plate* and Coin. T. ct qr. lb. •28 16 25 8 11 26 11 8 6 27 1 16 17 15 28 884 17 2 18 177 2 8 14 55 7 8 21 287 6 18 162 4 8 25 12ft 16 8 141 8 8 2 28 15 5 140 14 1 4 69 10 8 44 9 1 194 17 105 14 1 1 T. ct qr. lb 1 8 11 4 10 2 8 19 28 6 1 16 4 8 17 4 16 1 7 8 7 16 23 T 2 2 1 21 1 1 28 2 83 86 6 1 8 1 18 2 1 8 20 70 19 22 70 7 6 7ft 1 2 14 Old fbrRemaan- facture. T. ct qr. lb. 1 11 8 10 1ft 22 22 2 16 1 114 8 18 1 21 74 1 26 918 50 10 2 12 54 6 1 20 1 16 2 4 5 2 27 18 2 59 18 18 7 10 Ore. T. ct qr.lb. 1 14 5 5 11 2 24 2 6 8 28 2 18 7 5 10 1 13 7 6 8 12 8 12 2 9 1 12 1 18 7 15 1 12 2 8 2 8 4 2 20 16 8 11 4 15 22 6 10 8 11 1 11 115 8 11 8 6 10 12 28 11 14 T. ct qr. lb 714 14 4 400 4 2 16 880 18 2 6 851 10 8 24 1065 9 1 21 2178 16 2 25 1522 2 1 882 18 8 21 582 17 2 21 226 11 1 8 885 4 8 7 894 18 8 8 672 18 8 674 5 1 20 860 18 2 26 715 17 2 16 816 6 2 5 802 8 1 23 Copper Manufactures. Entered by Weifrht T. ct qr. lb. 4 17 1 9 81 18 2 28 88 1 8 28 8 2 16 18 2 8 8 15 10 18 1 27 81 19 11 86 12 1 25 41 17 18 85 18 8 1 49 11 15 49 2 1 2 42 16 1 Enterod by Value. £ ». d. 2,920 18 4 4,589 16 10 8.878 11 10 8,739 14 10 5,326 2 8,081 2,889 11 4 4,002 17 2 2,336 8 6 2,190 18 2,274 17 6 2,888 8,217 1 4 2,990 18 11 8,634 17 8 4,689 9 7 4,222 11 < 8,076 11 6 In this table the returns are also made up for the years 1832-48. / [140] METALLIC STATISTICS. ^ i 6 >aioooo«ee)»»aoio t- »- «P O O 00 :* ^ o ^ .-; C^h^OS^O t— r-> oa 5' ■J S I a o H 5 « & ■s E 4) ■«toe»iO»-iei«ooco to '9 04 04 04 ri 1-1 e* 00 O r^CO •* © CO o» t-Tio lo •^ 04 ef '^©«0<00a'^<0'^© * 1-1 T-t e«ototoeoo»o»eo t-oo^c4«c>C4 24ri i-ieoe4©4*»— ©»» te-^i-iifis-"*©'^ o(f»-^«fief'^04" eo © o i It ! "8 * ^ s> ^ >. S.S a « « « c :£ 3 o I (4 n 00 OQ 00 O M o H H O » Pk O b4 O o £4 P P4 ^ a 9 o •^ao«e©io>Oi-*©©©ocM4e Ci) »^ao © i-iSeo»-©aooo©oo •^ ^ t- b- ■* •^ 00 f-ie4r^ m 9 Of ■c 9 O fa i a •< oo©b-'<«>©epe*eee4C4ei>' rssti5'*s«)3»-©'*> 00.© aa© r- © I— «e 00 '^ t-. ( rH OT© id'o* 04 of I.*" •Q«©©eo©>Oi-)oe<) ' rH rHrHrnrHTH rH rH ©IA©^lO04)QTf©©»-© r-»-r-oh-r-iOe4i-'^©ao U©©0>Or'©<00404©00^ 104 • h- IQ 04 1-1 3" « 00 ' ©10 04 04 ©OO^ g' o o«f •* 04 1-1 ~ METALLIC STATISTICS. Account of Sales of Copper Ores in Cornwall, 1849. FIBST QUABTEB. tl41] DatoofSaU. >P'^??'0?t"T*'??r*j5>' o »- '♦ *i-irH ,.Hi-(rH IX 04 04 © 04 C4 © ©» oo -H M< CO ^ >-• Mt»©©h-QO©h» 0»rH 1-irH rH W »-;.Q0 ©_© aO *- efi-Ti-ri-J' eio >Oi-l 04© rHCO eCef s© rHe4 a s § o E ■< t^©©©IOrHCner-l©<0 .©O0«ij«0»i-'©00«0»- ©Ot*-!©©*^-^©©© eo©»-iQii»-aoi»'»cc4 cjj©'«>ecoo^oi-ii<'^©© ©f^OOof ©JOcTrH'^© « O 04 04 rH 1-1 rH ^ >ei»«0O«»h-rH,.HQO >©e4©t«ooaDO4'«0 eo eoo4 1-1 I •({©I*©©©©©©©© rH Tl ^^©04)C©e4©©090 •» i-trH rHi-t rH«ooj»-.«oo«©e<5« ©»-©04h-aor-ao©« cj s,©. >o o CO © -« © © o »-^«T-05e4©«tf rH e4 04rHT-( rH,OrH©e»«a^^ C4 04i-irH 4 1 a I © © 04 o« IP p.i 5 M a> .^ sS T^ • •••>• I X t • • • I • t S Ij C55S. ft ^ fi"S en C a, c-S C ^kOS^csMOSmpQS Janaarv 11 ... 18.., 25 ... Febraary 1 ... •» 8 March 24.... X • w • • V • • • • 16 .... 2S .... 29 .... Avenfra ATCrage Prio«. SUiuburd. Produce. ' £ t. d. £ «. d. 87 T 8t 4 12 6 84 12 93 10 ?J 5 4 9 18 95 16 7i 4 6 91 16 9 5 10 90 8 91 5 18 6 104 7 4 10 6 106 18 8 • 5 14 6 104 12 8 J 6 5 6 99 T H 6 18 107 5 U 5 1 6 Qnantity of Or*. 21 C5wt 1,818 2,638 8,841 8,988 2,146 2,990 2,5&t 8,684 2,67T 2,885 8,665 ToUl 98 13 I 8i I 5 4 5 < 86,098 SECOND QUARTER. Compated Qiuuitity of fine Ck>pper. Ton8.Cwt. 152 18 255 804 293 192 19 287 178 14 278 281 272 Amonntof S*leB. 8 6 2 7 276 10 2,981 11 £ «. 8,876 18 14,846 18 17,874 10 17,166 12 11,819 1 17,728 1 11,535 16 19,882 16 16,818 1 19,122 19,598 6 Value of Or« | to prodooe on*: Ton of Copper. 188,607 6 £ «. 54 15 56 4 58 16 58 11 61 5 61 15 6i 11 71 6 72 15 70 4 70 17 d. 8 7 9 1 1 1 8 6 8 7 68 4 6 April My June 5.... 106 18 7 r I 12 ... 104 14 8: 19 .... 99 17 9 26 .... 112 8 6 8 ... 105 8 7 10 .... 100 9 8 17 .... 98 18 9 24.... 98 5 I 81 .... 93 1 7* 7 .... 90 14 8 21 .... 86 16 9 28 .... 99 8 64 M .... 98 16 2 7-985 5 6 8,942 5 18 2,547 6 16 6 2,741 4 18 6 2,671 5 6 6 8,791 6 8 6 2,584 6 7 6 2,398 4 5 8,961 4 9 8,948 4 11 2,496 5 2 2,929 8 14 2,628 5 2 2 86,681 298 8 20,907 8 6 70 7 4 210 12 16,048 10 71 9 1 262 15 18,699 8 6 71 8 4 176 5 12.428 6 6 70 9 9 290 11 20,206 69 10 11 210 19 14,092 6 6 66 16 1 232 15 16,278 11 66 12 7 281 7 16,785 18 6 59 9 8 805 18 17,612 1 57 11 2 201 7 11,407 19 6 56 13 2 264 18 14,916 18 56 8 6 170 19 9,724 8 6 56 17 8 2.906 14 187,167 15 6 64 7 THIRD QUARTER. July 5.... •i 12 .... u 19 .... u aO • ■ • • August 2 .... u 9 .... u 28 .... u 80 September 6 — ti 18 ... . M 20 .... « ST ..«. 96 17 . 7t 94 9 6* 91 11 10 100 7- 93 14 7- 95 19 8* 94 1 9} 108 2 ?l 108 3 108 16 8. 99 17 9i 106 10 7* 4 5 6 9 13 10 6 Total....! 97 u 1 18-066 10 6 8 10 6 2 6 8 18 5 8 5 16 6 6 14 5 2 6 4 4 5 6 6 4 10 3,598 2,638 2,115 8,628 8,881 2,595 3,041 2,977 3,801 2,6U 2,467 8,790 274 6 221 2 212 14 264 6 280 15 224 2 296 19 183 800 10 220 16 233 281 7 87,108 1 2,992 17 16,679 18,918 18,662 16,473 17,087 14,863 18,624 11.599 20,549 15,663 16,475 19,554 Oft 50 17 4 6 2 6 6 9 6 15 6 12 6 15 6 3 5 6 60 16 1 62 18 6 64 4 8 62 6 7 60 18 S 64 1 10 62 14 5 68 2 8 68 7 8 70 9 9 70 14 8 69 10 FOURTH QUARTER. October 4 . « 11 . H 18 . " 25 . Noyemberl *» 8 « 22 « 29 Decembers " 18 •* SO » ST Total 106 102 98 110 104 102 7 7 1 8 8 1 97 16 108 108 15 104 18 100 l3 110 17 104 10 11 It ?i n 7 n 8 9 6> 4 6 16 1 6 10 4 4 5 18 11 6 11 4 5 5 6 4 16 2 12 7 10 6 6 6 6 6 7-696 5 5 7 8,998 1,926 2,694 2,718 8,965 2,677 2,858 4,220 4,864 2,887 2,627 2,879 288 6 164 19 245 9 166 7 291 6 209 5 224 13 293 16 817 8 229 8 228 1 156 4 191,495 11 6 64 19 9 19,126 18 67 10 8 11,587 15 6 70 6 16.983 10 6 69 8 10,906 6 65 11 8 19,616 2 6 66 19 11 14,267 8 6 68 8 8 15,494 6 6 68 19 5 20,121 16 68 9 9 22,627 2 70 19 6 16,124 19 70 5 10 16,059 16 70 8 5 10,778 16 68 19 6 86,508 12,810 2 198,444 11 6 68 16 9 / iWy ^tf iW J*2] METALLIC STATISTICS. Produce of Lead Ore and Lead in the United Kingdom, for the Year 184& By EoBKBT Hunt, Esq., Keeper of the Mining Records. METALLIC STATISTICS. [143] Mines. Cornwall. Calington, Hael Mary Ann, ... Huel Trelawny . . . . Hue! Trebane Herodsfoot Eest Huel Rose . . . . North Huel Rose... Cargol Oxnams Huel Rose Cubert Holmbush Callestock Devonshire. Tamar Huel Adams East Tatnar Cionsols Huel Friendship . . . Huel Betsey Lydford Consols Cumberland and Alston Moor. Rainngill Scaleourn, Carre and Hanging Shaw . Capel Cieugh Small Cieugh Middle Cieugh Guddamgili Long Cieugh Browngill Bentyfields Veins Cowperdyke Heads Brigalburn Veins Brown ley Hill Veins Bentfleld Sun. V. K Eng... Blagill Veins Carrs West of Nent Vein . . Grass Fields Veins Gallisill Syke Veins Gailigill Burn Hndgill Burn Holvfields Veins Weflgill Cross Vein Rodderup Cieugh West End Tyne Bottom Veins Park Grove Sun Vein . . . Low Birchy Bank Dowkeburn West End Sundry mines under 10 tons Drigjdih Beck Waste.... Dry Mill Mine Greensides Woodend Force Cragg Keswick Mine Slaty Syke Calvert Dozey Slow Craig , Crossfell Mines , Sundry, under 10 tons .... Durluim & Northurnber- land. K and W. Allendale and Weardale Teesdale Mines Yarnberry Silver Tongue Derwent Mines Stanhope Burn Holly-well Lane Head Alier Gill Bollihope Fallow-deid Whitlicld Lead Ore Returns. Tonsw 957 884 413 422 721 5,a38 80 964 470 899 63 154 179 1,022 P6 287 9 6 4 424 288 146 139 81 80 60 1,664 603 85 14 241 227 119 76 89 81 176 24 188 68 98 1,470 80 21 19 95 44 80 40 1,560 86 •43 20 47 11 18 25 44 20 13,230 8,327 100 139 1,4S0 220 67 24 12 13 61 143 Lead Retunu. Tona 632 250 298 279 670 3,191 49 677 288 239 41 90 110 631 30 173 6 8 2 282 156 97 91 21 20 83 1,142 400 21 9 162 143 60 51 26 20 117 16 120 38 66 980 54 14 12 68 29 15 27 1,200 24 82 14 35 6 9 16 30 12 9,0S0 1,490 75 95 1,046 160 48 17 8 9 45 105 &i net. Westmoreland. Dufton and Silverband. Hilton and Marton Derbyshire. Sundry Mines Shropshire. Snail Beach White Grit and Batholea. Bog Mine Pennerley Somersetshire. Mendip.Hills Yorkshire. Swale Dale and Arkendale Cononley Grassington and Gambury I'ateley District Cardiganshire. Lisbume Mines Cwm-ystwy th Esgair-hir Cwm-sebon Llanfair Goginan Gogerddan Mines Nant-y-creiau Pen-y-bont-pren Cefb-cwm-brwyno Llwyn-malys Bwlch-cwm-erfln Bwlch Consols Nanteos Aberysfrwith, small mines . , Llanymaron , Llanbadarn , Bron-berllan , Carnarvonshire. Penrhyn-du Carmarthenshire. Nant-y-Mwyn Flintshire. Talargoch Fronfownog. Hendre Maes-y-Safn Pen-y-rhenblas Mold Mines , Long Rake , Mllwr , Dingle and Deep Level . Pair's Mine Trelogan Westminster Mines HalkinHall Garreg-y-boeth Bodel wyddan Belgrave Bryng-gwyrog Jamaica Bwlch-y-ddaufryn Gwern-y-mynydd Mostyn Bagillt (ore sold at) — Billings Caelanycraig Mostyu Clwtmilitia Montgomeryshire. ... Llangynnog , Cae-conroy , Rhos-wydol , Dwn-gwm, or Dyfegnvm.! Craig-Uhiwarth Bryndaii and Pen-y-clyn '. Gom Ma«!hynlleth, includine Deljfe * Lead Ore Re tarns. Tons. 246 278 6,185 8,463 606 139 41 4,068 699 1.159 987 2,454 120 116 81 80 1,288 248 17 88 86 61 40 289 60 20 11 83 15 21 807 1,500 1,695 1,040 1.18S 1,160 219 89 117 8S7 21 15 659 89 6 106 875 11 885 20 18 18 46 46 14 12 26 61 88 26 18 27 155 43 645 Lead RetoRia. Tons. 184 204 8,870 2,486 289 72 16 29 8,040 437 707 609 1,624 71 70 17 68 816 162 10 22 24 83 26 192 80 10 6 18 7 14 804 980 1,168 688 824 819 153 21 81 648 15 10 451 26 4 69 261 7 699 16 18 8 20 20 7 6 11 81 20 15 9 16 100 80 800 Mlaea. Montgomeryshire. Nantmelyn FrontbalUn Merionethshire. Cowarch Tyddynglwadus Ibklakd. Newtonards Conlig Shallee Glenmalure Lugitnure Barristown LeadOrs Lead Retuma. Returns- Tons. Tons. 19 13 15 7 74 42 18 12 616 866 814 179 840 202 45 89 422 295 176 116 Mines. Lead Ore Returns. Scotland. Woodhead Afton Lead Mines . . Stroniton Mines.,.. Cairnsmore Black Craig Lead Hills Mine.... Wanlock Mine Isle of Max. Foxdale Mines, including Peel's shipment, 6iC Laxey Douglas Retuma. Ton& Tons. 460 820 80 66 286 141 476 811 86 58 800 200 960 660 ,566 1,084 695 461 260 ITO Table showing the Total Quantity of Lead Ore raised and Lead smelted in the United Kingdom in 1848. Districts. Cornwall Devonshire Cumberland Durham and Northumberland Westmoreland Derbyshire Shropshire Somersetshire Yorkshire Walks : — Cardiganshire Carnarvonshire . . . .• Carmarthenshire Flintshire Montgomeryshire Merionethshire Irblamd 8cX)TLAin> Isle ofMak Making a Total of. Lead Ore. Tons. 10,494 l,a34 8,272 . 18,815 519 5,185 4,130 41 6,848 55,633 4,902 21 SOT 10,056 927 92 16,305 1.912 2,588 2,521 78,964 Tons. 6,614 844 5,684 14,658 888 8,870 2,769 29 4,798 89,143 S;180 14 904 7,069 601 64 11,123 1,188 1,786 1,665 54,858 Lead Ore and Lead imported and exported during 1848. Imported.— 1,^8 tons of lead ore; pig and sheet lead, 8,788 tons: retained for homo consamption. 2,157 tons. ^ Rrportfd.—\^ tons of lead ore: pig and rolled lead, 4,977 tons: shot, 1,151 tons: litharge, red and white lead, 2,292 tons; foreign lead, in sheet and pig, 3,747 tons. The Welsh sales include also the following lead ores :— Australian, 69 tons; Belgian, 85 tons: German. 44 tons; Portugal, 79 tons; Prussian, 112 tons; Sardinian, 112 tons. ^^ The total ainount of lead ore raised and sold in the United Kingdom, for the year 1848, was 78.964 tons, and metallic lead sold 54,853 tons; while in 1847, the amount of lead ore was 79,311 ton* and lead 53,410 tons— showing a decrease in the quantity of ore in 1848, as compared with a former year, of 347 tons but an Increase in the metal of 1,443 tons. The price of English pig at the close of 1847 was 17/. 10«. per ton, and at the same period of 1848, 15t 15«. per ton. A comparist)ii of the two years thus shows no very great fluctuation in home trade : but, on referring to the imports mid exports we And a great increa-sj in the latter year. The imports of lead ore in 1847 were 507 tons, and pig and sheet lead 894 tons; and the exports 86 tons of ore, and 8,435 tons of metal : while in 1848 the imports were 1,298 tons of ore, and 3,788 tons of metal ; and the exports 185 tons of ore, and (), 128 tons of metal— showing an Increase in the imports of 791 tons of ore, and 3,894 tons of metal: and m the exyoria of 49 tons of «.re, and 2,693 tons of pig, sheet lead, and shot, and exclusive of inanufacture TS CB at a 5 «• o a o so 9 Of METALLIC STATISTICS. §9 ■< ;Mae«w-«t-t-oooeoeo«Ma0OOMOTeioeae>aeoooon^oooos> c^ t- c* — B J! 3 3 ■ •ac-f-i 00 e •- to e« I- eo eo usocetit "f-iio ,ao--e«ioo»eoe« .oco» *'<■*» £oOO nc««o .©•^O '0000«*0»00* l^0« t ^^■^'0 > > • s ii 1^ »« iMM lOifeia (O • '(DO a> »* o 9» ws OO ar> 00 tp o At* 100 O'* > o 3 or °1§ gS •< •Seeo OO ooo« o oe I I • • « C,ooo eoot ooom e eo no ^oee 'eoa> 'eooia 'e ,e«» It-"* i^oe-eo • at > • o«^ 9e I • • ^lovoo • ra • le 3 S TOO ooo »-»-•- o II £ooo ooooo* fl fl I ■ • • >• o oe ooooot o ^OiOO * r^0DO>S« |s loeooocD •^eoeoiD 'c-ioatoo* • • Maaot- «n'»f «(j QO^o* -^ c< ^ 00 1* 00 a> fc-'^'-oo^ ^OOOO 000000000000* e I- t • e o ' o ' • « S3 « to CP Pi O O 3 ^ i 3 n .^.^ ■ s«MO«Cie«*a«oe .»e*c00Cr-»'00r-C« *•! r- OS c« CO e* «>^o>_^ oo'tfTcoet 00 M^ o 5 ^oi-i-t-c^oooi — i-.o«»i e« •"• bxcoi-ioMMati-i er ^akOio«e^o r^ coco COC* r^ t-» B 2 g Q I- ■< rf oe CO e « c« » « oio to t- wcow I » o^'^oo .-^* ^ ^^ ^^ ^ O* O* c* o* ke«e«cMco ■ oia^wn«f>> • gS f ^e>aroo>r-e>o 0> r- ^ ^ '^ ec lO H oc^ao^'o,*^e»_.« lo i £aio0coooa>'<«oe ».o«e«MMc«e«i • «jooe«ooo o -£3 ^ >» ^ 1 m »- cJ "2 i C^ TS s S s S^ o CO a a es ■< «9>v-io^ 00 ' ^^ COOaiA coc«o M „ o> •» ■* 1- c* - irc^s « O o £ooo«ooao e) «;ceo*ot-oio «» b '^ — — H't- C* I- O i I' E fa .S . .« •- m a"* • I 5, • c S i !•* I c e J |5;s£ o fa a 1^ 5« it ^1 O » a ■ »^ *^ ■«-» • •^ .Cuu «i-i Is 5f SI i.S'S = 'I e ss Sec . ^. o 9 o > * o 0-" ft, •^" "^^ M Sis. lis 0-5*0 S « "^ ^ gs METALIJC STATISTICS. CORNISH COPPER ORES. [146] Annual average Produce, Price, and Standard for Nine Years, fi^>m 1841 to 1849, inclusive, of Copper Ores sold at Cornish Ticketing, with the highest and lowest Prices of Cake Copper in each Year. Year. Standard. Prodace. Prices Cake Copper— per Ton. £ a. d. £ 9. d. ££«. ^ '"^^^ --P« .i.^"K^''l.*^!lf"'T,T ^*»!,fi:»«««s of the powder depends on the weight of the pestles, the height of their fall and the period of their action upon the ore; but in the stamped exposed to a stream of water, the retention of the matters in the trough is longer or shorter according to the facility given for their escape. Sometimes these matter! flow out of the chest oyer its edges, and the height of the line they must surmount lias an influence on the size of the grain j at other times, the water and the pounded matter W^ II II II 148 METALLURGY. METALLURGY. Ut irhich it carries off, are made to pass through a grating, causing a kind of siAing at th€ same time. There are, however, some differences in the results of these two methods. Lastly^ the quantity of water that traverses the trough, as well as its velocity, has an influence on the discharge of the pounded matters, and consequently on the products of the stampers. The size of the particles of the pounded ore being different, according to the variable hardness of the matters which compose them, suggests the means of classing them, and distributing them nearly in the order of their size and specific gravity, by making the water, as it escapes from the stamping trough, circulate in a system of canals called a labyrinthy where it deposites successively, in proportion as it loses its velocity, the earthy and metallic matters it had floated along. These metalliferous portions, especially when they have a great specific gravity like galena, would be deposited in the first passages, were it not that from their hardness being inferior to that of the gangue, they are reduced to a much finer powder, or into thin plates, which seem to adhere to both the watery and earthy particles ; whence they have to be sought for among the finest portions of the pul- verized gangue, called slime, schlich, or schlamme. There are several methods of conducting the stamps; in reference to the size of the grains wished to be obtained, and which is previously determined agreeably to the nature of the ore, and of the gangue ; its richness, &c. The height of the slit that lets the pounded matters escape, or the diameters of the holes in the grating, their distance, the quantity of water flowing in, its velocity, &c., modify the result of the stamping oper- ation. When it is requisite to obtain powder of an extreme fineness, as for ores that are to be subjected to the process of amalgamation, they are passed under millstones, as in common com mills ; and after grinding, they are bolted so as to form a species of flour ; or they are crushed between rolls. See Lead and Tin. Washing of ores. TV, The ores pounded under the stamps are next exirased to very delicate operations, both tedious and costly, which are called the washings. Their purpose is to separate mechanically the earthy matters from the metallic portion, which must therefore have a much higher specific gravity ; for otherwise, the washing would be impracticable. The medium employed to diminish the difference of specific gravity, and to move along the lightest matters, is water ; which is made to flow with greater or less velocity and abundance over the schlich or pasty mud spread on a table of various inclination. But as this operation always occasions, not only considerable expense, but a certain loss of metal, it is right to calculate what is the degree of richness below which washing is unprofitable ; and on the other hand, what is the degree of purification of the schlich at which it is proper to stop, because too much metal would be lost comparatively with the expense of fusing a small additional quantity of gangue. There cannot, indeed, be any fixed rule in this respect, since the elements of these calculations vary for every work. Before describing the different modes of washing, we must treat of the sifting or riddling, whose purpose, like that of the labyrinth succeeding the stamps, is to distribute and to separate the ores (which have not passed through the water stamps) in the order of the coarseness of grain. This operation is practised particularly upon the debris of the mine, and the rubbish produced in breaking the ores. These substances are put into a riddle, or species of round or square sieve, whose bottom is formed of a grating instead of a plate of metal pierced with holes. This riddle is plunged suddenly and repeatedly into a tub or cistern filled with water. This liquid enters through the bottom, raises up the mineral particles, separates them and keeps them suspended for an instant, after which they fall down in nearly the order of their specific gravities, and are thus classed with a certain degree of regularity. The sieve is sometimes dipped by the immediate effort oC the washer ; sometimes it is suspended to a swing which the workman moves ; in order that the riddling may be rightly done, the sieve should receive but a single movement from below upwards ; in this case the ore is separated from the gangue, and if there be different specific gravities, there are formed in the sieve as many distinct strata, which the workman can easily take out with a spatula, throwing the upper part away when it is too poor to be re-sifted. This operation by the hand-sieve, is called riddling m the iitbj or riddling by deposite. We may observe, that during the sifting, the particles which can pass across the holes of the bottom, fall into the tub and settle down there ; whence they are afterwards gath* ered out, and exposed to washing when they are worth the trouble. Sometimes, as at Poullaouen, the sieves are conical, and held by means of two handles by a workman ; and instead of receiving a single movement, as in the preceding method^ the sifter himself gives them a variety of dexterous movements in succession. His object is to separate the poor portions of the ore from the richer ; in <»tler to subject the former to the stamp mill. Among the sittings and washings which ores are made to undergo, we must notice as among the most usefhl and ingenious, those practised by iron gratings, called on tlie Con- tinent grilhs anglaises, and the step-washings of Hungary, laveries a gradins. These methods of freeing the ores from the pulverulent earthy matters, consist in placing them, at their out-put from the mine, upon gratings, and bringing over them a stream of water, which merely takes down through the bars the small fragments, but carries off the pulver- ulent portions. The latter are received in cisterns, where they are allowed to rest long enough to settle to the bottom. The washing by steps is an extension of the preceding plan. To form an idea, let us imagine a series of grates placed successively at different levels, so that the water, arriving on the highest, where the ore for washing lies, carries off a portion of it, through this first grate upon a second closer in its bars, thence to a third, &c., and finally into labjrrinths or cisterns of deposition. The grilles anglaises are similar to the sleeping tables used at Idria. The system of these tn gradins is represented in^g. 904. There are 5 such systems in the works at Idria, for 904 the sorting of the small morsels of quicksilver ore, intended for the stamping mill. These fragments are but moderately rich in metal, and are picked up at random, of various sizes, from that of the fist to a grain of dust. These ores are placed in the chest a, below the level of which 7 grates are distributed, so that the fragments which pass through the first 6, proceed by an inclined conduit on to the second grate c, and so in succession. (See the conduits 2, o, p). In front, and on a level with each of the grates 6, c, d, &c., a child is stationed on one of the floors, 1, 2 3, to 7. A current of water, which falls into the chest a, carries the fragments of ore upon the grates. The pieces which remain upon the two grates 6 and c, are thrown on the adjoin- ing table r, where they undergo a sorting by hand; there the pieces are classified, 1. into gangue to be thrown away ; 2. into ore for the stamp mill ; 3. into ore to be sent directly to the furnace. The pieces which remain on each of the succeeding grates, d, €,/, g, h, are deposited on those of the floors 3 to 7, in front of each. Before every one of these shelves a deposite-sieve is established, (see /, «,) and the workmen in charge of it stand in one of the corresponding boxes, marked 8 to 12. The sieve is represented only in front of the chest h, for the sake of clearness. Each of the workmen placed in 8, 9, 10, 11, 12, operates on the heap before him; the upper layer of the deposite formed in his sieve, is sent to the stamping house, and the in- ferior layer directly to the furnace. As to the grains which, after traversing the five grates, have arrived at the chest x, they are washed in the two chests y, which are analogous to the German chests to be presently described. The upper layer of what is deposited in y is sent to the furnace ; the rest is treated anew on three tables of percussion, similar to the English brake-sieves^ also to be presently described. After several successive manipulations on these tables, an upper stratum of schlich is obtained fit for the furnace ; an intermediate stratum, which is washed anew by the same process ; and an inferior strattun, that is sent to the system of stamps, ^g. 905. 905 This figure represents the general ground plan of a stamping and washing mill. The Mamps F are composed of two batteries similar to^g. 903. The ore passes in succession ander three pestles of cast iron, each of which is heavier the nearer it is to the sieve through which the sand or pounded matter escapes. In the upper part of the figure we see issuing from the stamps, two conduits destined to receive the water and the metalliferous sand with which it is loaded. The first, marked r. s, tr, is used only when a certain quality of ore is stampedy richer in metal than is / 160 METALLURG\. METALLURGY. 151 II It 1^ I asuaUy treated by means of the second conduit, the first being closed. The second eo» duit, or that employed for ordinary manipulation when the other is shut, is indicated by r, 0'7, B ; then by 0*58 and 0-29. These numbers express the depth of the corresponding portions of this conduit. From f to b, the conduit or water-course is divided into three portions much shallower, called the rich conduity the middle conduit^ and the inferior Beyond the basin b, the conduit takes the name of labyrinth. There the muddy sedi: ments of ore are deposited ; being the finer the further they are from the stamps r. Darts indicate the direction of the stream in the labyrinth. On the German chestsj placed at 3, the sand derived from the rich and middle conduits is treated, in order to obtain three distinct qualities of achlich, as already mentioned, p is a cloth-covered table, for treating the deposite of the German chests at 3. m n are two sweep tables Id batai\ for treating the ore collected in the lower conduit, which precedes the midmost of the three German chests. Upon the three similar tables k t v, are treated in like manner the muddy deposites of the labyrinth, which forms suite to three parallel German chests situated at 3, not shown for want of room in the figure, but connected in three rectangular zigzags with each other, as well as by a transverse branch to the points 0*7 and p. At the upper part of these five sweep tables, the materials which are to undergo washing are agitated in two boxes o o, by small paddle-wheels. We shall now describe the percussion-tables used in the Hartz, for treating the sand of ore obtained from the conduits represented above. Figs. 906. 907. and 908, exhibit a plan, a vertical section, and elevation, of one of these tables, taken in the direction of its length. The arbor or great shaft in prolonga- tion from the stamps mill, is shown in section perpendicularly to its axis, at a. The cains or wipers are shown round its cir- cumference, one of them having just acted on w. These cams, by the revolu- tion of the arbor, cause the alternating movements of a horizontal bar of wood o, «, which strikes at the point u against a table rf, 6, e, u. This table is suspended by two chains ty at its superior end, and by two rods at its lower end. After having been pushed by the piece o, «, it rebounds to strike against a block or bracket B. A lever p, q, serves to adjust the inclination of the moveable table, the pivots q being points of suspension. The ore-sand to be washed, is iilaced in the chest a, into which a current of water runs. The ore floated onwards by the water, is carried through a sieve on a sloping small table Xf under which is concealed the higher end of the moveable table rf, by c, u ; and it thence falls on this table, diffusing itself uniformly over its surface. The particles deposited on this table form an oblong talus (slope) upon it; the successive per- cussions that it receives, deter- mine the weightier matters, and consequently those richest in metal, to accumulate towards its upper end at u. Now the workman by means of the lever p, raises the lower end d a little in order to preserve the sam<; degree of inclination to the surface on which the deposite is «;trewed. According as the substances are swept along by the water, he is careful to remove them from the middle of the table towards the top, by means of a wooden roller. With this intent, he walks on the table dbcuy where the sandy sediment has sufficient consistence to bear him. When the table is abundantly charged with the washed ore, the deposite is divided into three bands or segments db,bCyCU. Each of these bands is removed separately and thrown into the particular heap assigned to it. Every one of the heaps thus formed becoinei afterwards the object of a separate manipulation on a percussion table, but always accord- ing to the same procedure. It is sufficient in general to pass twice over this table the mat- ters contained in the heap, proceeding from the superior band c u, in order to obtain a pure $chlich ; but the heap proceeding from the intermediate belt 6 c, requires always a greater number of manipulations, and the lower band d b still more. These successive manipu- lations are so associated that eventually each heap furnishes pure schlichy which is obtained from the superior band c u. As to the lightest particles which the water sweeps away beyond the lower end of the percussion table, they fall into conduits ; whence they are lifted to undergo a new manipulation. Fig. 909 is a profile of a plan which has been advantageously substituted, in the Hartz, for that part of the preceding apparatus which causes the jolt of the piece o « against the table dbcu. By means of this plan, it is easy to vary, according to the circumstances of a manipulation always delicate, the force of percussion which a bar X y, ought to communicate by its extremity y. With this view, a slender piece of wood u is made to slide in an upright piece, v x, adjusted upon an axis at v. To the piece « a rod of iron is connected, by means of a hinge z ; this rod is capable of entering more or less into a case or sheath in the middle of the piece v x, and of being stopped at the proper point, by a thumb-screw which presses against this piece. If it be wished to increase the force of percussion, we must lower the point z ; if to diminish it, we must raise it. In the first case, the extremity of the piece tt, advances so much further under 910 909 911 the cam of the driving shaft / ; in the second, it goes so much less forwards ; whereby the adjustment is produced. Figs. 910 and 911 represent a complete system of sleeping tables^ tables dormantes ; — such as are mounted in Idria. Fig. 911 is the plan, and fig. 910 a vertical section. The mercurial ores, reduced to a sand by stamps like those of fig. 905 pass into a series of conduits a Oybby c c, which form three successive floors below the level of the floor of the works. The sand taken out of these conduits is thrown into the cells q ; whence they are transferred into the trough «, and water is run upon them by turning two stopcocks for each trough. The sand thus diffused upon eaclk table, runs off with the water by a groove /, comes upon a sieve h, spreads itself upon the board g, and thence falls into the slanting chest, or sleeping table i k. The under surface k of this chest is pierced with holes, which may be stopped at pleasure with wooden plugs. There is a conduit wi, at the lower end of each table, to catch the light par- ticles carried off by the water out of the chest t fc, through the holes properly opened, while the denser parts are deposited upon the bottom of this chest. A general conduit n passes across at the foot of all the chests ik; it receives the refuse of the washing operations. JFtg. 912 is a set of stamping and washing works for the ores of argentiferous galena, as mounted at Bockunese, in the district of Zellerfeldt, in the Hartz. A is the stamp mill and its subsidiary parts ; among which are a, the driTing or / 152 METALLURGY. maia shaft ; b, the overshot water-wheel ; c c, six strong rings or hoops of cast iron. for receiving each 912 a cam or tappet ; g, the brake of the machine ; fe, /c, k, the three standards of the stamps ; / /, &.c. six pestles of pine wood, shod with lumps of cast iron. There are two chests, out of which the ore to be ground falls spontaneously into the two troughs of the stamps. Of late years, however, the ore is mostly supplied by hand ; the water-course terminates a short dis- tance above the middle of the wheel b. There is a stream of water for the service of the stamps, and conduits proceeding from it, to lead the water into the two stamp troughs ; the conduit of dis- charge is common to the two batteries or sets of stamps through which the water carries ofl' the sand or stamped ore. There is a moveable table of separation, mounted with two sieves. The sands pass immediately into the conduit placed upon a level with the floor, and separated into two compartments, the first of which empties its water into the second. There are two boards of separation, or tables, laid upon the ground, with a very slight slope of only 15 inches from their top to their bottom. Each of these boards is divided into four cases with edges; the whole being arranged so that it is possible, by means of a flood-gate or sluice, to cause the superfluous water of the case to pass into the following ones. Thus the work can go on without interruption, and alternately upon the two boards. There are winding canals in the labyrinth, n, n, n, in which are deposited the particles carried along by the water which has passed upon the boards. The depth of these canals gradually increases from 12 to 20 inches, to give a suitable descent for maintaining the water-flow. At d, two percussion tables are placed. F G are two German chests, h j are two percussion tables, which are driven by the cams z z, fixed upon the main shaf\ xy. k k' are two sloping sweep tables ( i\ / 156 METALLURGY. vapors from one compartment to another. The ores r being distributed upon the biUct^ of wood 1 1, whenever these are fairly kindled, they are covered with smaU ore, and then with rammed earth I L Towards the point m, for a space of a foot square, the ores are covered with moveable stone slabs, by means of which the fire may be regulated, by the displacement of one or more, as may be deemed necessary. The liquid sulphur runs into the recipient g, whence it is laded out from lime to time. The sublimed sulphur passes into the conduit / e and the chamber A, from which it is taken out, and washed with water, to free it from sulphuric acid, with which it is somewhat impregnated : it is after- wards distilled in cast-iron retorts. The residuum of the pyrites is turned to account in Sweden, for the preparation of a common red color much used as a pigment for wooden Diiildings. The reverberatory furnace affords one of the best means of ustulation, where it is requisite to employ the simultaneous action of heat and atmospherical air to destroy certain combinations, and to decompose the sulphurets, arseniurels, &c. It is likewise evident that the facility thus offered of stirring the matters spread out on the sole, in order to renew the surfaces, of observing their appearances, of augmenting or diminish- ing the degree of heat, &c., promise a success much surer, a roasting far better executed, than by any other process. It is known, besides, that flame mingled with much unde- composed air issuing from the furnace, is highly oxydizing, and is very fit for burning away the sulphur, and oxydizing the metals. Finally, this is almost the only method of rightly roasting ores which are in a very fine powder. If it be not employed constantly and for every kind of ore, it is just because more economy is found in practising calcina- tion m heaps, or on areas enclosed by walls; besides, in certain mines, a very great num- ber of these furnaces, and many workmen, would be required to roast the considerable body of ores that must be daily smelted. Hence there would result from the construction of such apparatus and its maintenance a very notable outlav, which is saved in the other processes. But in every case where it is desired to have a very perfect roasting, as for blende from which zinc IS to be extracted, for sulphuret of antimony, &c., or even for ores reduced to a very fine powder, and destined for amalgamation, it is proper to perform the operation m a reverberatory furnace. When very fusible sulphurous ores are treated, the workman charged with the calcination must employ much care and experience, chiefly in the man- agement of the fire. It will sometimes, indeed, happen, that the ore partially fuses ; when It becomes necessary to withdraw the materials from the furnace, to let them cool and grind them anew, in order to recommence the operation. The construction of these furnaces demands no other attention than to give to the sole or laboratory the suitable size, and so to proportion to this the grate and the chimney that the heating may be eliected with the greatest economy. The reverberatory furnace is always employed to roast the ores of precious metals, and especially those for amalgamation ; as the latter oflen contain arsenic, antimony, and other volatile substances, they must be disposed of in a peculiar manner. The sole, usually very spacious, is divided into two parts, of which the one farthest off from the furnace is a little higher than the other. Above the vault there is a space or chamber in which the ore is deposited, and which communicates with the laboratory by a vertical passage ; which serves to allow the ore to be pushed down, when it is dried and a little heated. The flame and the smoke which escape from the sole or laboratory pass into condensing chambers, before entering into the chimney of draught, so as to deposite in them the oxyde of arsenic and other substances. When the ore on the part of the sole farthest from the grate has suflTered so much heat as to begin to be roasted has become less fusible, and when the roasting of that in the nearer part of the sole is completed, the former is raked towards the fire-bridge, and its ustulation is finished by stirring it over frequently with a paddle, skUfully worked, through one of the doors left in the side for this purpose. The operation is considered to be finished when the vapors and the smell have almost wholly ceased; its duration depending obviously on the nature of the ores. When this furnace is employed to roast very arsenical ores, as the tin ores of Schlack- enwald in Bohemia, and at Ehrenfriedensdorf in Saxony, the arsenical pyrites of Geyer (in Saxony), &c., the chambers of condensation for the arsenious acid are much more extensive than in the furnaces commonly used for roasting galena, copper or even silver ores. ' Figs. 919, 920, 921, represent a reverberatory furnace employed in the smelting works of Lautenthal, in the Hartz, for roasting the schlichs of lead ores, which contain much blende or sulphuret of zinc. In fig. 919 we see that the two parts a b, b c, are absolutely like, the two furnaces being built in one body of brickwork. Fig. 920 is the plan of the furnace b c, taken at the level e f of ^ig. 919. Fig. 9*21 is a'vcrtical section of the similar furnace a b, taken in the prolongation of the line g h in fig. 920. METALLURGY. 157 a is the fire-place of the furnace, its grate and ash-pit. b is the conduit of vaporiza- tion, wliich communicates with the chambers c ; c, chambers into which the vaporized 919 920 A B C substances are deposited ; d, chimney for 4he escape of the smoke of the fire place a, sJler it has gone through the space be c ; e', is the charging door, with a hook hanging in front to rest the long iron rake upon, with which the materials are turned over ; /, chamber contain* ing a quantity of schlich destined for roasting ; this chamber communicates with the vaulted corridor (gallery) d, seen in ^g. i919 ; g, orifice through which the schlich is thrown into the furnace ; h, area or hearth of the reverberator)' furnace, of which the roof is certainly much too high ; i, channels for the escape of the watery vapors ; k, /, front arcade, between which and the furnace, properly speaking, are the two orifices of the conduits, which termi- nate at the channels m, m', m is the channel for carrying towards the chimney rf, the vapors which escape by the door e'. w is a walled-up door, which is opened from time to time, to take out of the chambers c, c, the substances that may be deposited in them. At the smelting works of Lautenthal, in such a roasting furnace, from 6 to 9 quintals (cwts.) of schlich are treated at a time, and it is stirred frequent- ly with an iron rake upon the altar h. The period of this operation is from 6 to 12 hours, according as the schlich may be more or less dry, more or less rich in lead, or more or less charged with blende. When the latter substance is abundant, the process requires 12 hours, with about 60 cubic feet of cleft billots for fuel. In such furnaces are roasted the cobalt ores of Schneebei^ in Saxony, the tin ores of Schlackenwald in Bohemia, of Ehrenfriedersdorf in Saxony, and elsewhere ; as also the arsenical pyrites at Geyer in Saxony. But there are poison towers and extensive con- densing chambers attached in the latter case. See Arsenic. Figs. 922, 923, 924, represent the reverberatory furnace generally employed in the Hartz, in the district of Mansfeldt, Saxony, Hungary, &c., for the treatment of black cop- per, and for refining rose copper upon the great scale. An analogous furnace is used at Amlreas- ^^^^^^ berg for the liquefaction or purification of the ■ Mji )^|^|H|^H1 mattes, and for workable lead when it is much HI -^^JBWKBm Ji loaded with arsenic. "i I • BKi* Fig. 922 presents the elevation of the fur- nace parallel to the line i k, of the plan^g. 923 ; which plan is taken at the level of the tuyere », of fig. 924 ; fig. 924 is a vertical section in the line l m, fig. 923. k represents one of two basins of reception, brasqued with clay and charcoal ; n, n, two tuyeres, through which enters the blast of two pairs of bellows, like those shown at Cupellation of Silver ; q, door by which the matter to be melted is laid upon the sole of the furnace ; r, r, two points where the sole is perforated, when necessary to run off the melted matter into cither of the basins h ; x, door through which the slags or cinders floating upon the sur- 922 Ml III 11 158 METALLURGY. li If \i ^ face of the melted metal are raked out ; y, door of the fire-place. The fuel is laid ui)Oii a grate above an ash-pit, and below the arch of a reverberatory which is contiguous to the dome or cap of the furnace properly so called. In the section, Jig. 924 the following parts may be noted ; 1, 2, 3, mason-work of the foundation ; 4, vapor channels or con- 923 924 duits, for the escape of the humidity; 5, bed of clay; 6, brasque composed of clay and charcoal, which forms the concavity of the hearth 925 i^ -nx 926 927 Figs. 925, 926, 927, show the furnace employed for liquation in one of the principal smelting works of the Hartz. Fig. 927 exhibits the working area charged with the liquation cakes and charcoal, sup« ported by sheets of wrought iron j being an image of the process in action. Fig. 926 is the plan, in the line r g, of Jig. 925. A liquation cake is composed of— Black copper holding at least 5 or 6 loths (2| or 3 oz.) of silver per cwt., and weighing 90 to 96 lbs. Lead obtained from litharge, 2 cwts. Litharge, \ cwt. From 30 to 32 cakes are suc- cessively worked in one operation, which lasts about 5 hours ; the fur- nace is brought into action, as usual, with the aid of slags ; then a little litharge is added; when the lead begins to flow, the copper is intro- duced, and when the copper flows, lead is added, so that the mixture of the metals may be effected in the best way possible. From 8 to 16 of these cakes (pains) are usually placed in the liquation furnace, Jigs, 925, 926, 927. The operation lasts 3 or 4 hours, in which time about 1| quintals of char- coal are consumed. The cakes are covered with burning charcoal, supported, as I have said, by the iron plates. The workable lead obtained flows off" towards the basin in front of the furnace ; whence it is laded out into moulds set alongside. See Jig. 926 If the lead thus obtained be not sufficiently rich in silver to be worth cupellation, it is employed to form new liquation cakes. When it contains from 5 to 6 loths of silver per cwt., it is eubmitted to cupellation in the said smelting works. See Silver. The trompe, or water blowing engine, Jigs. 928, 929, 930. Fig. 928 is the elevation ; Jig. 929 is a vertical section, made at right angles to the elevation. The machine is formed of two cylindrical pipes, the bodies of the trompe b b, set upright, called the funnels, which terminate above in a water cistern a, and below in a close basin under c, called the tub or METALLURGY. 159 drum. The conical part p, of the funnel has been called etranguiUon, being strangled, as it were, in order that the water discharged into the body of the trompe shall not fill the 928 pipe in falling, but be divided into many streamlets. Below this narrow part, eight holes, q q, are perforated obliqueiy through the substance of the trompe, called the vent-holet or nostrils, for admitting the air, which the water carries with it in its descent. The air afterwards parts from the water, by dashing upon a cast-iron slab, placed in the drum upon the pedestal d. An aperture /, at the bottom of the drum, allows the water to flow away after its fall ; but, to prevent the air from escaping along with it, the water as it issues is received in a chest I mno, divided into two parts by a vertical slide-plate be- tween m n. By raising or lowering this plate, the water may be maintained at any desi- red level within the drum, so as to give the included air any determinate degree of pressure. The superfluous water then flows oflf by the hole o. The air-pipe «, Jig. 929 is fitted to the upper part of the drum ; it is divided, at the point /, into three tubes, of which the principal one is destined for the furnace of cupel- .ation, while the other two g g, serve for different melting furnaces. Each of these tubes ends in a leather pocket, and an iron nose-pipe fc, adjusted in the tuyere of the furnace. At Pesey, and in the whole of Savoy, a floodgate is fitted into the upper cbtem a, to regulate the admission of water into the trompe ; but in Camiola, the funnel p is closed with a wooden plug, suspended to a cord, which goes round a pulley mounted upon a horizontal axis, as shown in Jig. 930. By the plug a being raised more or less, merely the quantity of water required for the operation is admitted. The plug is pier- ced lengthwise with an oblique hole c c, in which the small tube c is inserted, with its top some way above the water level, through which air may be admitted into the heart of the column descending into the trompe p q. The ordinary height of the trompe apparatus is about 26 or 27 feet to the upper level of the water cistern j its total length is 11 metres (36 feet 6 inches), and its width 2 feet. r / i ! > J I » i I 160 METALLURGY. to give room for the drams. It is situated 10 metres (33^ feet) from the melting furnace. This is the case at the smelting works of Jauerberg, in Upper Carniola. OF THB ASSAT OF ORV. Assays ought to occupy an important place in metallurgic instructions, and there ia reason to believe that the knowledge of assaying is not sufficiently diffused, smce its practice is so often neglected in smelting houses. Not only ought the assays of the ores under treatment to be frequently repeated, because their nature is subject to vary ; but the different products of the furnaces should be subjected to reiterated assays, at the several periods of the operations. When sUver or gold ores are in question, the doci- mastic operations, then indispensable, exercise a salutary conUol over the metallurgic processes, and afford a clear indication of the quantities of precious metal which they ought to produce. ^ . . ^ .v j r By the title Jlssays, in a metaUurgic point of view, is meant the method ol ascertain- ing for any substance whatever, not only the presence and the nature of a metal, butiU proportional quantity. Hence the operations which do not lead to a precise determi- nation of the metal in question, are not to be arranged among the assays now under consideration. Experiments made with the blow-pipe, although capable of yielding most useful indications, are like the touchstone in regard to gold, and do not constitute genuine assays. . , .^, Three kinds of assays may be practised in different circumstances, and with more or less advantage upon different ores. 1. The mechanical assay ; 2. the assay by the dry way ; 3. the assay by the humid way. ... »• r ♦!. 1. 0/ Tnechanical assays.— These kinds of assays consist m the separation ol tne substances mechanically mixed in the ores, and are performed by a hand-washing, m a smaU trough of an oblong shape, caUed a sebiUa. After pulverizing with more or less pains the matters to be assayed by this process, a determinate weight of them is put into this wooden l>owl with a little water ; and by means of certain movements and some precautions, to be learned only by practice, the Hghtest substances may be pretty exactly separated, namely, the earthy gangues from the denser matter or metallic particles, with- out losing any sensible portion of them. Thus a schlich of greater or less purity wiU be obtained, which may afford the means of judging by its quahty of the richness of the as- sayed ores, and which may thereafter be subjected to assays of another kind, whereby th« whole metal may be insulated. « /. i. ^ j Washing, as an assay, is practised on auriferous sands ; on all ores from the stampsy and even on schlichs aheady washed upon the great scale, to appreciate more nicely the degree of purity they have acquired. The ores of tin in which the oxyde is often disseminated in much earthy gangue, are well adapted to this species of assay, because the tin oxyde is very dense. The mechanical assay may also be employed in reference to the ores whose metallic portion presents a uniform composition, provided it also possesses con siderable specific gravity. Thus the ores of sulphuret of lead (galena) being susceptible of becoming ahnost pure sulphurets (within I or 'Z per cent.) by mere washing skilfully conducted, the richness of that ore in pure galena, and consequently in lead, may be at once concluded ; since 120 of galena contain 104 of lead, and 16 of sulphur. The sul- phuret of antimony mingled with its gangue may be subjected to the same mode of assay, and the result will be still more direct, since the crude antimony is brought mto the mar- ket after being freed from its gangue by a simj'e fusion. , . .. ^ ,, The assay by washing is also had recourse to for ascertaining if the scoria or other products of the furnaces contain some metallic grains which might be extracted from them by stamping and washing on the great scale ; a process employed considerably with the jcorue of tin and copper works. , v . . v Of assays by the dry way.— The assay by the dry way has for its object, to show the nature and proportion of the metals contained in a mineral substance. To make a good assay, however, it is indispensably necessary to know what is the metal associated with it, and even within certain Umits, the quantity of the foreign bodies. Only one metal is commonly looked after ; unless in the case of certain argentiferous ores. The mineralogical examination of the substances under treatment, is most commonly sufficient to afford data in these respects; but the assays may always be varied with different views, before stopping at a definite result ; and in every instance, only such assays can be con- fided in, as have been verified by a double operation. This mode of assaying requires only a little experience, with a simple apparatus ; and is of such a nature as to be practised currently in the smelting works. The air furnace and crucibles employed are described in aU good elementary chemical books. These assays are usually performed with the addition of a flux to the ore, or some agent for separating the earthy from the metallic substances ; and they possess a peculiar advan- tage relative to the smelting operations, because they offer many analogies between METALLURGY. 161 reflults on the great scale and experiments on the smalL This may even enable vm often to deduce, from the manner m which the assay has succeeded with a certain flui, and at a certain degree of heat, valuable indications as to the treatment of the ore ia the great way. See FuENAfc>- In the smelting houses which purchase the ore, as in Germany, it is necessary to bestow much attention upon the assays, because they serve to regulate the quality and the price of the schlichs to be delivered. These assays are not bv any means fr«e from difficulties, especially when ores containing several useful metals are treated, and which are to be dosed or proportioned ; ores, for example, including a notable quantity of lead, copper, and silver, mixed together. In the central works of the Hartz, as well as in those of Saxony, the schlichs as de- livered are subjected to docimastic assays, which are verified three times, and by three difierent persons, one of whom is engaged for the interests of the mining partners, another for that of the smelting house, and a third as arbiter in case of a difl'erence. If the first two results of assaying differ by | loih (or ^ ounce) of silver per cwt. cf schlich, the operations must be resumed ; but this rarely happens. When out of the three assayfu the one differs from the two others by no more than \ loth of silver per c>Rt., but bj more in one, and by less in another, the mean result is adopted. As to the contents of the schlich in lead, the mean results of the assays must be taken. The differences allowed are three pounds for the schlich^ when it contains from 12 to 30 per cent, of lead, increoB- ing to six pounds for schlich, when it contains less than 55 per cent, of that metal. Assaying forms, in great establishments, an important object in reference to lime and expense. Thus, in the single work of Franckenscharn, in the Hartz, no less than 300 assays have to be made in a threefold way, every Monday, without taking into accounl the several assays of the smelting products which take place every Thursday. Formerly Aiixes more or less compound were employed for these purposes, and every assay com about fifteen pence. At present all these assays are made more simply, by much cheaper methods, and cost a penny farihing each upon an average. Of the assays by the humid way. — The assays by the humid way, not reducible to very simple processes, are true chemical analyses, which may in fact be applied with much advantage, either to ores, or to the products of the furnace ; but which cannot be expected to be practised in smclting-houses, on account of the complication of apparatus and reagents they require. Moreover, an expert chemist is necessary to obtain results that can be depended on. The directors of smelting-houses, however, should never neglect any opportunities that may occur of submitting the materials operated upon, as well as their products, to a more thorough examination than the dry way alone can eliect. One of the great advantages of similar researches is to discover and appreciate the minute quantities of injurious substances which impair the malleability of the metals, which give them seve- ral bad qualities, about whose nature and cause more or less error and uncertainty prevaft. Chemical analysis, rightly applied to metallurgy, cannot fail to introduce remarkable improvements into the processes. See the different metals, in their alphabetical places. For assays in the dry way, both of stony and metallic minerals, the process of Dr. Abich deserves recommendation. It consists in mixing the pulverized mineral with 4 oi 6 times its weight of carbonate of baryta in powder, fusing the mixture at a white heal, and then dissolving it, after it cools, in dilute muriatic acid. The most refractory mine- rals, even corundum, cyanate, staurolite, zircon, and feldspar, yield readily to this treat- ment. This process may be employed with advantage upon poor refractory ores. The platinum crucible, into which the mixed materials are put for fusion, should be placed ir a Hessian crucible, and surrounded with good coke. The manganese raised in England exceeds 2000 tons. M. Heron de Villefosse inserted in the last number of the AnnaUs des MiM» for J627;; the following statistical view of the metallic products of France : — Lead in pigs (saumons) - - . Litharge - - - . - Sulphuret of lead, ground galena (alquifoux) - Black copper ..... Antimony . - . - . Manganese ..... Crude cast-iron .... Bar iron ..... Steel --..•. Silver in ingots .... Vol. n. 11 Tons. 103 513 112 164 91 765 25,606 127,643 3,500 / I I Jl i I , :l! 102 METER, GAS. M i'^t. The total value of which is estimated at 80 millions of francs, or about 3 400,000 pounds sterling. AICTALS; {Metaux, Fr. ; Metalle, Germ.) are by far the most numerous class of nndecompouiided bodies m chemical arrangements. They amount to 43 • of which t form with oxygen, bodies possessed of alkaline properties: these are, l! pota-ssium; 2. sodium ; 3. lithium ; 4. barium ; 6. strontium ; 6. calcium ; 7. magnesium ; for evea magnesia, the last and feeblest base, tinges turmeric brown, and red cabbage green. iTie next five metals form, with oxygen, the earths proper ; they are, 8. yttrium ; 9. glucmum; 10. aluminum; 11. zirconium; 12. thorium. The remAinin 1 '1^ )tt ! h '! 166 MINEa general systems of rocks, to which they have given the name of formations or deposita. A large proportion of these mineral systems consists of parallel planes, whose length and breadth greatly exceed their thickness ; on which account they are called stratified rocks ; others occur in very thick blocks, without any parallel stratification, or horizontal seams of considerable extent. The stratiform deposites are subdivided into two great classes ; the primary and the secondary. The former seem to have been called into existence before the creation of organic matter, because they contain no exuvice of vegetable or animal beings ; while the latter are more or less interspersed, and sometimes replete with organic remains. The primary strata are characterized, moreover, by the nearly vertical or highly inclined position of their planes ; the secondary lie for the most part in a nearly horizontal position. Where the primitive mountains graduate down into the plains, rocks of an intermediate character appear, which, though possessing a nearly vertical position, contain a few vestiges of animal beings, especially shells. These have been called transition, to indicate their being the passing links between the first and second systems of ancient deposites ; they are distinguished by the fractured and cemented texture of their planes, for which reason they are sometimes called conglomerate. Between these and the truly secondary rocks, another verj-^ valuable series is interposed in certain districts of the globe ; namely, the coal-measures, the paramount formation of Great Britain. The coal strata are disposed in a basin-form, and alternate with parallel beds of sandstone, slate-clay, iron-stone, and occasionally limestone. Some geologists have called the coal-measures the medial formation. In every mineral plane, the inclination and direction are to be noted ; the former being the angle which it forms with the horizon, the latter the point of the azimuth or horizon, towards which it dips, as west, north-east, south, &c. The direction of the bed is that of a horizontal line drawn in its plane ; and wJiich is also denoted by the point of the compass. Since the lines of direction and inclination are at right angles to each other, the first may always be inferred from the second ; for when a stratum is said to dip to the east or west, this implies that its direction is north and south. The smaller sinuosities of the bed are not taken into account, just as the windings of a river are neglected in stating the line of its course. Masses are mineral deposites, not extensively spread in parallel planes, but irregular heaps, rounded or oval, enveloped in whole or in a great measure by rocks of a ditferent kind. Lenticular masses being frequently placed between two horizontal or inclined strata, have been sometimes supposed to be stratiform themselves, and have been accord- ingly denominated by the Germans liegende stocke, lying heaps or blocks. The orbicular masses often occur in the interior of unstratified mountains, or in the bosom of one bed. Nests, concretions, nodules, are small masses found in the middle of strata ; the first be- ing commonly in a friable state ; the second often kidney-shaped, or tuberous ; the third nearly round, and incrusted, like the kernel of an almond. Lodes, or large veins, are flattened masses, with their opposite surfaces not parallel, which consequently terminate like a wedge, at a greater or less distance, and do not run parallel with the rocky strata in which they lie, but cross them in a direction not far from the perpendicular ; often traversing several different mineral planes. The lodes are sometimes deranged in their course, so as to pursue for a little way the space between two contiguous strata ; at other times they divide into several branches. The matter which fills the lodes is for the most part entirely different from the rocks they pass through, or at least it possesses peculiar features. This mode of existence, exhibited by several mineral substances, but which has been long known with regard to metallic ores, suggests the idea of clefts or rents having been made in the stratum posterior to its consolidation, and of the vacuities having been filled with foreign matter, either immediately or after a certain intervaL There can be no doubt as to the justness of the first part of the proposition, for thero may be observed round many lodes undeniable proofs of the movement or dislocation of the rock ; for example, upon each side of the rent, the same strata are no longer situated in the same plane as before, but make greater or smaller angles with it ; or the stratum upon one side of the lode is raised considerably above, or depressed considerably below, its counterpart upon the other side. With regard to the manner in which the rent has been filled, different opinions may be entertained. In the lodes which are widest near ■ the surface of the ground, and graduate into a thin wedge below, the foreign matter would seem to have been introduced as into a funnel at the top, and to have carried along with it in its fluid state portions of rounded gravel and organic remains. In other cases, other conceptions seem to be more probable ; since many lodes are largest at their under part, and become progressively narrower as they approach the surface j from which circumstance it has been inferred that the rent has been caused by ao MINES. ler expansive force acting from within the earth, and that the foreign matter, having been injected in a fluid state, has afterwards slowly crystallized. This hypothesis accounU much belter than the other for most of the phenomena observable in mineral veins, for the alterations of the rock at their sides, for the crystallization of the different substances interspersed in them, for the cavities bestudded with little crystals, and for many minute peculiarities. Thus, the large crystals of certain substances which line the walls of^ Hollow veins, have sometimes their under surfaces besprinkled with small cr5-stals of sulphurets. arseniurets, &c., while their upper surfaces are quite smooth ; suggesting the idea of a slow sublimation of these volatile matters from below, by the residual heat, and their condensation upon the under faces of the crystalline bodies, already cooled. This phenomenon affords a strong indication of the igneous origin of metalli- ferous veins. In the lodes, the principal matters which fill them are to be distinguished from the accessory substances ; the latter being distributed irregularly, amidst the mass of the first, in crystals, nodules, grains, seams, &c. The non-metalliferous exterior purtion, which is often the largest, is called gangue, from the German gang, vein. The position of a vein is denoted, like that of the strata, by the angle of inclination, and the point of the horizon towards which they dip, whence the direction is deduced. Veins, are merely small lodes, which sometimes traverse the great ones, ramifying i* various directions, and in different degrees of tenuity. A metalliferous substance is said to be disseminated, when it is dispersed in crystals.. spansles, scales, globules, &c., through a large mineral mass. Certain ores which contain the metals most indispensable to human necessities, have been treasured up by the Creator in very bountiful deposites ; constituting either great masses in rocks of different kinds, or distributed in lodec, veins, nests, concretions, or beds with stony and earthy admLxtures ; the whole of which become the objects of mineral ex- ploration. These precious stores occur in different stages of the geological formations ; but their main portion, after having existed abundantly in the several orders of the pri- mary strata, suddenly cease to be found towards the middle of the secondary. Iron ores are the only ones which continue among the more modern deposites, even so high as the beds immediately beneath the chalk, when they also disappear, or exist merely as color- ing matters of the tertiary earthy beds. The strata of gneiss and mica-slate constitute in Europe the grand metallic domain. There is hardly any kind of ore which does not occur there in suflicient abundance to become the object of mining operations, and many are found nowhere else. The tran- sition rocks, and the lower part of the secondary ones, are not so rich, neither do they contain the same variety of ores. But this order of things, which is presented by Great Britain, Germany, France, Sweden, and Norway, is far from forming a general law ; since in equinoctial America the gneiss is but little metalliferous ; while the superior strata, such as the clay-schists, the sienilic porphyries, the limestones, which complete the tran- sition series, as also several secondarj' deposites, include the greater portion of the immense minei-al wealth of that region of the globe. All the substances of which the ordinary metals form the basis, are not equally abundant in nature ; a great proportion of the numerous mineral species which figure in our classsi- fications, are mere varieties scattered up and down in the cavities of the great masses or lodes. The workable ores are few in number, being mostly sulphurets, some oxydes, and carbonates. These occasionally form of themselves very large masses, but more frequent- ly they are blended with lumps of quartz, feldspar, and carbonate of lime, which form the main body of the deposite ; as happens always in proper lodes. The ores in that case are arranged in small layers parallel to the strata of the formation, or in small veins which traverse the rock in all directions, or in nests or concretions stationed irregularly, or finally disseminated in hardly visible particles. These deposites sometimes contain appa- rently only one species of ore, sometimes several, which must be mined together, as they seem to be of contemporaneous formation ; whilst, in other cases, they are separable, having been probably formed at difi'erent epochs. In treating of the several metals in their alphabetical order, I have taken care to describe their peculiar geological positions, and the rocks which accompany or mineralize them. In mining, as in architecture, the best method of imparting instruction is to display the master-pieces of the respective arts, which speak clearly to the mind throug:h the medium of the eye. It is not so easy, however, to represent at once the general effect of a mine, as it is of an edifice ; because there is no point of sight from which the former can be sketched at once, like the latter. The subterraneous structures certainly afford some of the finest examples of the useful labors of man, continued for ages, under the guidance of science and ingenuity ; but, however curious, beautiful, and grand in them- selves, they cannot become objects of a panoramic view. It is only by the lights of ge- ometry and geology that mines can be contemplated and surveyed, either as a whole or ii\ their details j and, therefore, these marvellous subterranean regions, in which roads are col / t , I ; I 168 MINES. many hundred miles long, are altogether unknown or disregarded by men of the wcrW. Shonld any of them, perchance, from curiosity or interest, descend into these dark recesses of the earth, they are prepared to discover only a few insulated objects which they may think strange or possibly hideous ; but they cannot recognise either the symmetrical disposition of mineral bodies, or the laws which govern geological phenomena, and B^rve as sure guides to the skilful miner in his adventurous search. It is by exact plans and sections of subterraneous workings, that a knowledge of the nature, extent, and distribution of mine.al wealth can be acquired. 931 . A general view of mining operations. ■ "•% '"mi; ',v0,k -V •■7/;/. § . M2;>:f !:::«' ij'i k ■ M m ft'-r 1 • 1" ^^SS-'5^S'-1? ,E .^^'^^&.-"H^-:^- ^^pp^ /.-■ ■ ''^iik'ti^^^^p ?-^^«;;.;^ As there is no country in the world so truly rich and powerful, by virtue of its mineral stores, as Great Britain, so there are no people who ought to take a deeper interest in their scientific illustration. I have endeavored in the present article to collect from the most authentic sources the most interesting and instructive examples of mining operations. To the magnificent work of Ville-Fosse, Sur la Richesse Minerale, no longer on sale, I have to acknowledge weighty obligations ; many of the figures being copied from his great Atlas. Lodes or mineral veins are usually distinguished by English miners into at least four ftpecies. 1. The rake vein. 2. The pipe vein. 3. The flat or dilated vein ; and 4. The interlaced mass (stock-werke), indicating the union of a multitude of small veins mixed in every possible direction with each other, and with the rock. 1. The rake vein is a perpendicular mineral fissure ; and is the form best known among practical miners. It commonly runs in a straight line, beginning at the super- ficies of the strata, and cutting them downwards, generally further than can be reached. This vein sometimes stands quite perpendicular; but it more usually inclines or hangs over at a greater or smaller angle, or slope, Avhich is called by the miners the hade ox hading of the vein. The line of direction in which the fissure runs, is called the beann^ of the vein. 2. The pipe vein resembles in many respects a huge irregular cavern, pushing forward into the body of the earth in a sloping direction, under various inclinations, frorh an angle of a few degrees to the horizon, to a dip of 45°, or more. The pipe does not in general cut the strata across like the rake vein, but insinuates itself between them ; so that if the plane of the strata be nearly horizontal, the bearing of the pipe vein will be eonformable ; but if the strata stand up at a high angle, the pipe shoots down nearly headlong like a shaft. Some pipes are very wide and high, others are very low and narrow, sometimes not largei than a common mine or drift. 3. The Jlat or dilated vein, is a space or opening between two strata or beds of stone, the one of which lies above, and the other below this vein, like a stratum of coal MINES. 169 between its roof and pavement ; so that the vein and the strata are placed in the same plane of inclination. These veins are subject, like coal, to be interrupted, broken, and thrown up or down by slips, dikes, or other interruptions of the regular strata. In the case of a metallic vein, a slip often increases the chance of finding more treasure. Such veins do not preserve the parallelism of their beds, characteristic of coal seams ; but vary excessively in thickness within a moderate space. Flat veins occur frequently in limestone, either in a horizontal or declining direction. The flat or strata veins open and close, as the rake veins also do. 4. The interlaced mass has been already defined. To these may be added the accumulated vein, or irregdiar mass (Jtmtzenwerke), a great deposite placed without any order in the bosom of the rocks, apparently filling up cavern- ous spaces. The interlaced masses are more frequent in primitive formations, tnan m the others ; and tin is the ore which most commorily affects this locality. See figure of Tin mine. The study of the mineral substances, called gangues or vein-stones, which usually accompany the different ores, is indispensable in the investigation and working of mines. These gangues, such as quartz, calcareous spar, fljior spar, heavy spar, &c., and a great number of other substances, although of little or no value in themselves, become of great consequence to the miner, either by pointing out by their presence that of certain useful minerals, or by characterizing in their several associations, different deposites of ores of which it may be possible to follow the traces, and to discriminate the relations, often of a complicated kind, provided we observe assiduously the accompanying gangues. Mineral veins are subject to derangements in their course, which are called shifts or faults. Thus, when a transverse vein throws out, or intercepts, a longitudinal one, we must commonly look for the rejected vein on the side of the obtuse angle which the direction of the latter makes with that of the former. When a bed of ore is deranged by a fault, we must observe whether the slip of the strata be upwards or downwards ; for in either circumstance, it is only by pursuing the direction of the fault that we can recover the ore ; in the former case by mounting, in the latter by descending beyond the dislocation. When two veins intersect each other, the direction of the offcast is a subject of interest, both to the miner and the geologist. In Saxony it is considered as a general fact that the portion thrown out is always upon the side of the obtuse angle, a circumstance which holds also in Cornwall ; and the more obtuse the angle, the out-throw is the more con- siderable. A vein may be thrown out on meeting another vein, in a line which approaches either towards its inclination or its direction. The Cornish miners use two different terms to denote these two modes of rejection ; for the first case, they say the vein is beared ; for the second, it is started. The great copper lode of Carharack, d^fig. 932, in the parish of Gwenap, is one of the most instructive examples of intersection. The power or thickness of this vein is 8 feet ; its direction is nearly due east and west, and it dips towards the north at an inclination of two feet per fathom ; its upper part being in the killas (a greenish clay-slate) ; its lower part in the granite. The lode has suflTered two intersections ; the first produced by meeting the vein A, called Steven's Jluckan, which runs from north- east to south-west, and which throws the lode several fathoms out ; the second is producxl by another vein i, almost at right angles with the first, and which occasions another out- throw of 20 fathoms to the right side. The fall of the vein occurs therefore in the one case to the right, and in the other to the left ; but in both it is towards the side of the obtuse angle. This distribution is very singular ; for one part of the vein appears to have mounted while the other has descended, n. s. denotes North and South, d is the copper lode running east and west. A, i, are systems of clay-slate veins called fluckans ; the line over s, represents the down shift, and d' the up-shift. General observations on the localities of ores, and on the indications of metallic mines, 1 . Tin exists principally in primitive rocks, appearing either in interlaced masses, in beds, or as a constituent part of the rock itself, and more rarely in distinct veins. Tin ore is found indeed sometimes in alluvial land, filling up low situations between lofty mountains. 2. Gold occurs either in beds or in veins, frequently in primitive rocks ; though in other formations, and particularly in alluvial earth, it is also found. When this metal exists in the bosom of primitive rocks, it is particularly in schists ; it is not found in serpen- tine, but it is met with in graywacke in Transylvania. The gold of alluvial districts. t ii / 'j ^ 1 i I 'i \ H t " 5 170 MINES. called gold of washing or transport, occurs, as well as alluvial tin, among the debiis of the more ancient rocks. 3. Silver is found particularly in veins and beds, in primitive and transition formations ; though some veins of this metal occur in secondary strata. The rocks richest in it are; gneiss, mica-slate, clay-slate, graywacke, and old alpine limestone. Localities of silver- ore itself are not numerous, at least in Europe, among secondary formations; but it occurs in combination with the ores of copper or of lead. 4. Copper exists in the three mineral epochas ; 1 . in primitive rocks, principally in the state of pyritous copper, in beds, in masses, or in veins ; 2. in transition districts, some- times in masses, sometimes in veins of copper pyrites ; 3. in secondary strata, especially in beds of cupreous schist. 5. Lead occurs also in each of the three mineral epochas ; abounding particularly in primitive and transition grounds, where it usually constitutes veins, and occasionally beds of sulphureted lead (£?alena). The same ore is found in strata or in veins among secondary rocks, associated now and then with ochreous iron-oxyde and calamine (carbonate of zinc) ; and it is sometimes disseminated in grains through more recent 6. iron is met with in four different mineral eras, but in different ores. Among primi- tive rocks, magnetic iron ore and specular iron ore occur chiefly in beds, sometimes of enormous size; the ores of red or brown oxyde of iron (hematite) are found generally in veins, or occasionally in masses with sparry iron, both in primitive and transition rocks ; as also sometimes in secondary strata ; but more frequently in the coal-measure strata, as beds of clay-ironstone, of globular iron oxyde, and carbonate of iron. In alluvial districts we find ores of clay-ironstone, granular iron-ore, bog-ore, swamp-ore, and meadow-ore. The iron ores which belong to the primitive period have almost always the metallic aspect, with a richness amounting even to 80 per cent, of iron, while the ores in the posterior formations become in general more and more earthy, down to those in alluvial soils, some of which present the appearance of a common stone, and afford not more than 20 per cent, of metal, though its quality is oflen excellent. 7. Mercury occurs principally among secondary strata, in disseminated masses, along with combustible substances; though the metal is met with occasionally in primitive countries. 8. Cobalt belongs to the three mineral epochas ; its most abundant deposites are vems in primitive rocks ; small veins containing this metal are found, however, in secondary strata. 9. jlrUimmy occurs in veins or beds among primitive and transition rocks. 10. 11. Bismuth and nickel do not appear to constitute the predominating substance of any mineral deposites ; but they often accompany cobalt. 12. Zinc occurs in the three several formations : namely, as sulphuret or blende, partic- ularly in primitive and transition rocks ; as calamine, in secondary strata, usually along with oxyde of iron, and sometimes with sulphuret of lead. An acquaintance with the general results collected and classified by geology must be our first guide in the investigation of mines. This enables the observer to judge whether any particular district should, from thp nature and arrangement of its rocks, be suscepti. ble of including within its bosom, beds of workable ores; it indicates also, to a certain desree, what substances may probably be met with in a given series of rocks, and what loc'ality these substances will preferably affect. For want of a knowledge of these facts, many persons have gone blindly into researches equally absurd and ruinous. Formerly, indications of mines were taken from very unimportant circumstances; from thermal waters, the heat of which was gratuitously referred to the decomposition of pyrites ; from mineral waters, whose course is however often from a far distant source ; from vapors incumbent over particular mountain groups ; from the snows melting faster in one mineral district than another ; from the different species of forest trees, and from the "reater or less visor of vegetation, &c. In general, all such indications are equally fallacious with the divining rod, and the compass made of a lump of pyrites suspended by a thread. Geogtwstic observation has substituted more rational characters of metallic deposites, some of which may be called negative and others positive. The negative indications are derived from that peculiar geological constitution, which from experience or general principles excludes certain metallic matters ; for example, granite, and in general every primitive formation, forbids the hope of finding within them combustible fossils (pit-coal,) unless it be beds of anthracite ; there also it would be vain to seek for sal gem. It is very seldom that granite rocks include silver ; or limestones, ores of tin. Volcanic territories never afford any metallic ores worth the working; nor do extensive veins usually run into secondary and alluvial formations. The richei ores of iron do not occur in secondary strata ; and the ores of this metal peculiar to these localities, do not exist among primary rocks. MINES. 171 Amon" positive indications, some are proximate and others remote. The proximate are an efflorescence, so to speak, of the subjacent metaUic masses; magnetic attractiou for iron ores ; bituminous stone, or inflammable gas for pit-coal ; the frequent occurrence of fra«'ments of particular ores, &c. The remote indications consist in the geological epocha, and nature of the rocks. From the examples previously adduced, marks of this kind acquire new importance when in a district susceptible of including deposites of workable ores, the gangues or vein-stones are met with which usually accompany any particular metal. The general aspect of mountains whose flanks present gentle and continuous slopes, the frequency of sterile veins, the presence of metalliferous sands, the nei^-hborhood of some known locality of an ore, for instance, that of iron-stone in reference to coal, lastly, the existence of salt springs and mineral waters, may furnish M)me indications ; but when ferruginous or cupreous waters issue from sands or clays, such characters merit in general little attention, because the waters may flow from a great distance. No greater importance can be attached to metalliferous sands and saline springs. , . . , , j *• In speaking of remote indications, we may remark that in several places, and partic- ulariy near Clausthal in the Hartz, a certain ore of red oxyde of iron occurs above the most abundant deposites of the ores of lead and silver; whence it has been named by the Germans the iron^at. II appears that the iron ore rich in silver, whicu is worked in America under the name oipacos, has some analogy with this substance ; but iron ore is in general so plentifully diffused on the surface of the soil, that its presence can be re- garded as only a remote indication, relative to other mineral substances, except in the case of clav iron-stone with coal. t • v v -a e Of the instruments and operations of subterranean operations.— It is by the aid ot ge- ometry in the first place that the miner studies the situation of the mineral deposites, on the surface and in the interior of the ground ; determines the several relations of the veins and the rocks ; and becomes capable of directing the perforations towards a suitable The instruments are, 1. the magnetic compass, which is employed to measure the direction of a metallic ore, wherever the neighborhood of iron does not interfere with its functions ; 2. the graduated semi-circle, which serves to measure the inclination, which is also called the clinometer. 3. The chain or cord for measuring the distance of one point from another. 4. When the neighborhood of iron renders the use of the magnet uncertain, a plate or plane table is employed. . j .^ The dials of the compasses generally used in the most celebrated mines, are graduatea into hours; most commonly into twice 12 hours. Thus the whole limb is divided into 24 spaces, each of which contains 15° = 1 hour. Each hour is subdivided into 8 ^^Means of penetrating into the interior of the earth.— In order to penetrate into the inte- rior of the earth, and to extract from it the objects of his toils, the miner has at his dis- posal several means, which may be divided into three classes; 1. manual toolsy 2. gtt»- powderftindS.Jire. .. r n • The tools used bv the miners of Cornwall and Devonshire are the following : Fig, 933. The pick. It is a light tool, and somewhat varied in shape according to ar- 935 938 986 n V\ comstances. One side used as a hammer is called the pally and is employed to drive in the gads, or to loosen and detach prominences. The point is of steel, carefully tempered, and drawn under the hammer to the proper form. The French call it pointerolU, / I' ii; m 172 MINES. Fig. 934. The gad. It is a wedge of steel, driven into crevices of rocks, or into small openings made with the point of the pick. Fig. 935 The miner^s shovel. It has a pointed form, to enable it to penetrate among the coarse and hard fragments of the mine rubbish. Its handle being somewhat bent, a man's power may be convenienlly applied without bending his body. The blasting or shooting tools are : — A sledge or mallet Borer Claying bar Needle or nail Scraper Tamping bar fig. 986. — 937. — 938. — 939. — 940. — 941. Besides these tools the miner requires a powder-horn, rushes to be filled with gunpow- der, tin cartridges for occasional use in wet ground, and paper rubbed over with gunpow- der or srease, for the smi//* or fuses. The 6orcr, yig. 937, is an iron bar tipped with steel, formed like a thick chisel, and is used by one man holding it strai2:ht in the hole with constant rotation on its axis, while another strikes the head of it with the iron sledge or mallet, fig. 936. The hole is cleared out from time to time by the scraper, yjg. 940, which is a flat iron rod turned up at one end. If the ground be very wet, and the hole gets full of mud, it is cleaned out by a stick bent at the end into a fibrous brush, called a swab-stick. Fig. 942 represents the plan of blastins: the rock, and a section of a hole ready for firing. The hole must be rendered as drj' as possible, which is effected very simply by filling it partly with tenaci- ous clay, and then driving into it a tapering iron rod, which nearly fills its calibre, called the claying bar. This being forced in with great violence, condenses the clay into all the crevices of the rock, and secures the dryness of the hole. Should this plan fail, re- course is had to tin cartridges furnish- ed with a stem or tube, (see fig. 943,) through which the powder may be in- ^ flamed. When the hole is dry, and the charge of powder introduced, the nail, a small taper rod of copper, is inserted so as to reach the bottom of the hole, which is now ready for tamping. By this difficult and dangerous process, the gunpowder is confined, and the disruptive effect produced. Difllerent substances are employed for tamping, or cramming the hole, the most usual one being any sofl species of rock free from silicious or flinty particles. Small quan- tities of it only are introduced at a lime, and rammed very hard by the tamping-bar, which is held steadily by one man, and struck with a sledge by another. The hole being thus filled, the nail is withdrawn by putting a bar through its eye, and striking it upwards. Thus a small perforation or vent is left for the rush which communicates the fire. Besides the improved tamping-bar faced with hard copper, other contrivances have been resorted to for diminishing the risk of those dreadful accidents that frequently occur in this operation. Dry sand is sometimes used as a tamping material, but there are many rocks for the blasting of which it is ineffective. Tough clay will answer better in several situations. For conveying the fire, the large and long green rushes which grow in marshy ground are selected. A slit is made in one side of the rush, along which the sharp end of a bit of stick is drawn, so as to extract the pith, when the skin of the rush closes again by its own elasticity. This tube is filled up with gunpowder, dropped into the vent-hole, and made steady with a bit of clay. A paper smift, adjusted to burn a proper time, is then fixed to the top of the rush-tube, and kindled, when the men of the mine re- tire to a safe distance. In fig. 942 the portion of the rock which would be dislodged by the explosion, is that included between a and b. The charge of powder is represented by the white part which fills the hole up to c ; from which point to the top, the hole is filled with tamping. The smift is shown at d. Fig. 944 is an iron bucket, or as it is calk d in Cornwall, a kibble, in which the ore Is raised in the shafts, by machines called whims, worked by horses. The best kibbloe MINES. 17J are made of sheet-iron, and hold each about three hundred weight of ore : 120 kibbles are supposed to clear a cubic fathom of rock. 945 Fig. 945 represents the wheelbarrow used under ground for conveying ore and waste to the foot of the shafts. It is made of light deal, except the wheel, which has a narrow rim of iron. Fig. 946 represents Mr. Taylor's ingenious ventilator, or machine for renewing fresh air in mines. It is so simple in construction, so complete in its operation, requFres so little power to work it, and is so little liable to injury from wear, that nothing further of the kind can be desired in ordinary metallic mines. The shaft of the mine^is repre- sented at A ; at either the top or bottom of which the machine may be placed, as is found most convenient, but the foul air must be discharged into a floor, furnished' with a valve-door to prevent its return into the mine, b is the air-pipe from the mine, pass- ing through the bottom of the fixed vessel or cylinder c, which is formed of timber, and bound with iron hoops. It is filled with water nearly to the top of the pipe b, on which is fixed a valve opening upwards at d. e, the air, or exhausting cylinder of cast-iron, open at bottom, and suspended over the air-pipe, but immersed some way in the water. It is furnished with a wooden top, having an aperture fitted with a valve likewise open- ing upwards at f. This exhausting cylinder is moved up and down by the bob, g, brought into connexion with any engine, by the horizontal rod h ; the weight of the cylinder being balanced, if necessary, by the counterpoise i. The action is as follows : When the cylinder rises, the air from the mine rushes up through the pipe and valve d ; and when it descends, this valve shuts, and prevents the return of the air, which is expelled through the valve f. With a cylinder two feet in diameter and six feet long, working from two to three strokes per minute, 200 gallons of air may be discharged in the same time. Gunpowder is the most valuable agent of excavation ; possessing a power which has DO limit, and which can act everywhere, even under water. Its introduction, in 1615 caused a great revolution in the mining art. ' It is employed in mines in different manners, and in different quantities, according to circumstances. In all cases, however, the process resolves itself into boring a hole, and enclosing a cartridge in it, which is afterwards made to explode. The hole is always cylindrical, and is usually made by means of the borer,^g. 937, a stem of iron, termi- nated by a blunt-edged chisel. It sometimes ends in a cross, formed by two chisels set transversely. The workman holds the stem in his left hand, and strikes it with an iron mallet held in his right. He is careful to turn the punch a very little round at every stroke. Several punches are employed in succession, to bore one hole ; the first shorteii the latter ones longer, and somewhat thinner. The rubbish is withdrawn as it accumu- lates, at the bottom of the hole, by means of a picker, which is a small spoon or disc of iron fixed at the end of a slender iron rod. When holes of a large size are tp be i i' I 174 MINES. made, several men must be employed ; one to hold the punch, and one or more to wield the iron mallet. The perforations are seldom less than an inch in diameter, and 18 inches deep ; but they are sometimes two inches wide, with a depth of 50 inches. The gunpowder, when used, is most commonly put up in paper cartridges. Into the side of the cartridge, a small cylindrical spindle or piercer is pushed. In this state the cartridge is forced down to the bottom of the hole, which is then stuffed, by means of the tampin? bar,y?g. 941, with bits of dry clay, or friable stones coarsely pounded.* The piercer is now withdrawn, which leaves in its place a channel through which fire may be conveyed to the charge. This is executed either by pouring gunpowder into that passage, or by 'inserting into it reeds, straw stems, quills, or tubes of paper filled with gunpowder. This is exploded by a long match, which the workmen kindle, and then retire to a place of safetv As the piercer must not only be slender, but stiff, so as to be easily withdrawn when the hole is tamped, iron spindles are usually employed, though they occasionally give rise to sparks, and consequently to dangerous accidents, by their friction against the sides of the hole. Brass piercers have been sometimes tried ; but they twist and break too readily. . , , • . . *. Each hole bored in a mine, should be so placed in reference to the schistose structure of the rock, and to its natural fissures, as to attack and blow up the least resisting masses. Sometimes the rock is prepared beforehand for splitting in a certain direction, by means of a narrow channel excavated with the small hammer. The quantity of gunpowder should be proportional to the depth of the hole, and the re- sistance of the rock, and merely sufficient to split it. Anything additional would serve no other purpose than to throw the fragments about the mine, without increasing the useful effect. Into the holes of about an inch and a quarter diameter, and 18 inches deep, only two ounces of s:unpowder are put. j , , • *. It appears that the effect of the gunpowder may be augmented by leaving an empty space above, in the middle of, or beneath the cartridge. In the mines of Silesia, the con- sumption of gunpowder has been eventually reduced, without diminishing the pro- duct of the blasts, by mixing sawdust with it, in certain proportions. The hole has also been filled up with sand in some cases, according to Mr. Jessop's plan, instead of being packed with stones, which has removed the danger of the tamping operation. The ex- periments made in this way have given results very advantageous in quarry blasts with great charges of gunpowder ; but less favorable in the small charges employed in mines. , , , ^ « , Water does not oppose an insurmountable obstacle to the employment of gunpowder ; but when the hole cannot be made dry, a cartridge bag impermeable to water must be had recourse to, provided with a tube also impermeable, in which the piercer is placed. After the explosion of each mining charge, wedges and levers are employed, to drag away and break down what has been shattered. • i j Wherever the rock is tolerably hard, the use of gunpowder is more economical and more rapid than anv tool-work, and is therefore always preferred. A gallerj^, for example, a yard and k half high, and a yard wide, the piercing of which by the hammer formerlv cost from five to ten pounds sterling the runnmg yard, in Germany, is executed at the present day by gunpowder at from two to three pounds. When, how- ever a precious mass of ore is to be detached, when the rock is cavernous, which nearly nullifies the action of gunpowder, or when there is reason to apprehend that the shock caused by the explosion may produce an injurious fall of rubbish, hand-tools alone must ^IrTcert'ain* rocks and ores of extreme hardness, the use both of tools and gunpowdor becomes very tedious and costly. Examples to this effect are seen, m the mass of quartz mingled with copper pyrites, worked at Rammelsberg, m the Hartz, m the masses of stanniferous granite of Geyer and Altenbeig in the Erzgebirge of Saxony, &c. In these circumstances, fortunately very rare, the action of fire is used with advantage to diminish the cohesion of the rocks and the ores. The employment of this a^'ent is'^not necessarily restricted to these diflficult cases. It was formerly applied very often to the working of hard substances; but the intio«Juctioa of gunpowder into the raining art, and the increase in the price of woc^, occasion fire to be little used as an ordinary means of excavation, except in places where the scantiness of the poulation has ♦ Sir Rose Price invented a cap of bronze alloy, to tip the lower end of the iron rod; a contrivance now generally usfd in Cornwall. Before the Geological Socirtv of that county introduced this mventioB into practice, scarcly a month elapsed without some dreadful yxplosion sending the miner to an un- timely prave, or so injuring him by blown? out his eyes, or shuttoring his liinbs, as to render him a m-serable object of chartty for the rest of h-s days Scarcely ha* any accident happened since the em- nlovmenl of the new tompin?-bar. When the whole bar n-as made of the tin and copper alloy it wa* ex- neiisive and ant to bend : but the iron rod t-pppd with the bronze is both cheap and efrcctual. An in^eniont inrtriment, called the shifting cartridge, was lUYeuted by Mr Chinalls, and is described m the Transactioiu of the above soiiiety. MINES. 176 left a great extent of forest timber, as happens at Kongsberg in Norway, at Dannemora in Sweden, at Felsobanya in Transylvania, &c. The action of fire may be applied to the piercing of a gallery, or to the advancement of a horizontal cut, or to the crumbling down of a mass of ore, by the successive upraising of the roof of a gallery already pierced. In any of these cases, the process consists in forming bonfires, the flame of which is made to play upon the parts to be attacked. All the workmen must be removed from the mine, during, and even for some time after, the combustion. When the excavations have become sufficiently cool to allow them to enter, they break down with levers and wedges, or even by means of gunpowder, the masses which have been rent and altered by the fire. To complete our account of the manner in which man may penetrate into the interior of the earth, we must point out the form of the excavations that he should make in it. In mines, three principal species of excavations may be distinguished ; viz., shafts, galleries, and the cavities of greater or less magnitude which remain in the room of the old workings. A shaft or ptt is a prismatic or cylindrical hollow space, the axis of which is cither vertical or much inclined to the horizon. The dimension of the pit, which is never less than 32 inches in its narrowest diameter, amounts sometimes to several yards. Its depth may extend to 1000 feet, and more. Whenever a shaft is opened, means must be pro- vided to extract the rubbish which continually tends to accumulate at its bottom, as well as the waters which may percolate down into it; as also to facilitate the descent and ascent of the workmen. For some time a wheel and axle erected over the mouth of the opening, which ser\'e to elevate one or two buckets of proper dimensions, may be suffi- cient for most of these purposes. But such a machine becomes ere long inadequate. Horse-whims, or powerful steam-engines, must then be had recourse to ; and efiectual methods of support must be employed to prevent the sides of the shaft from crumbling and falling down. A Gallery is a prismatic space, the straight or winding axis of which does not usually deviate much from the horizontal line. Two principal species are distinguished ; the galleries of elongation^ which follow the direction of a bed or a vein ; and the transverse galleries, which intersect this direction under an angle not much different from 90**. The most ordinary dimensions of galleries are a yard wide, and two yards high ; but many still larger may be seen traversing thick deposites of ore. There are few whose width is less than 24 inches, and height less than 40 ; such small drifts serve merely as temporary expedients in workings. Some galleries are several leagues in length. We shall describe in the sequel the means which are for the most part necessary to support the roof and the walls. The rubbish is removed by wagons or wheelbarrows of various kinds. See Jig. 946 It is impossible to advance the boring of a shaft or gallery beyond a certain rate, because only a limited set of workmen can be made to bear upon it. There are some galleries which have taken more than 30 years to perforate. The only expedient for accelerating the advance of a gallery, is to commence, at several points of the line to be pursued, portions of galleries which may be joined together on their completion. Whether tools or gunpowder be used in making the excavations, they should be so applied as to render the labor as easy and quick as possible, by disengaging the mass out of the rock at Iwo or three of its faces. The eflfect of gunpowder, wedges, or picks, is then much mor< powerful. The greater the excavation, the more important is it to observe this rule. With this intent, the working is disposed in the form of steps, (gradins), placed like those of a stair ; each step being removed in successive portions, the whole of which, except the last, are disengaged on three sides, at the instant of their being attacked. The substances to be mined occur in the bosom of the earth, under the form of alluvial deposites, beds, pipe-veins, or masses, threads or small veins, and rake-veins. When the existence of a deposite of ore is merely suspected, without positive proofs, recourse must be had to labors of research, in order to ascertain the richness, nature, and disposition of a supposed mine. These are divided into three kinds ; open workings, subterranean workings, and boring operations. 1, The working by an open trench, has for its object to discover the outcropping or basset edges of strata or veins. It consists in opening a fosse of greater or less width, which, after removing the vegetable mould, the alluvial deposites, and the matters dis- integrated by the atmosphere, discloses the native rocks, and enables us to distinguish the beds which are interposed, as well as the veins that traverse them. The trench ought always to be opened in a direction perpendicular to the line of the supposed deposite. This mode of investigation costs little, but it seldom gives much insight. It is chiefly employed for verifying the existence of a supposed bed or vein. The subterranean workings afl'ord much more satisfactory knowledge. They are executed by diflferent kinds of perforations ; vi«., by longitudinal galleries hollowed out j ' * ; i i i7e MIKES. of the mass of the beds or veins themselves, in following their course; by lransver»e ^/Lrirpihed at right angles to the direction of the veins; by xncltru>d shafts, whi^ pSe the slope of the deposites, and are excavated in their mass; or, lastly, by perpen. ''Yf rvein or bed unveils itself on the flank of a mountain, it may be explored, according to the greater or less slope of its inclination, either by a longitudinal gallery opened in Us mas' ftom the outcropping surface, or by a transverse gallery faUing upon it m a cer- tain po it, from which either an oblong gallery or a sloping shaft may be opened. if our object be to reconnoitre a highly inclined stratum or a vein in ^ level countnr, we shaU obtain it with sufficient precision, by means of shafts, 8 or 10 yards deep, dug Tt 30 yards distance from one another ; excavated in the mass of ^^^^^ ^^^^^^^^^^^^^^^^^^^^ its deposite. If the bed is not very much inclined, only 4o°, for example vertical shafts mustTe o^ned in the direction of its roof, or of the superjacent rocky stratum, and StUeries Xst be driven from the points in which they meet the ore, in the hue of its "^'When'the rocks which cover valuable minerals are not of very g^eat hardne^^^as happens generally with the coal formation, with pyritous and aluminous slates, sal gem, and' ome'o'her minerals of the secondary strata, the borer is e-Pf^Y^^jf .'l^^^^^^ ascertain their nature. This mode of investigation is ^.^^'"^^i.^fj' ^^^^.J^o^^^^^ cases, a tolerably exact insight into the riches of the interior. The method of using the borer has been described under Artesian Wells. OF MINING IN PARTICULAK. The mode of working mines is two-fold ; by open excavations, jind subterranean. WorW^s in the ope'n air present few difficulties, and occasion little expense, unless when pushed to a great depth. They are always preferred for working deposites litUe distant' from the surface; where, in fact, other "^^t^^^ds cannot be resorted^^^^^ ^.ubstance to be raised be covered with incoherent matters. The only rules to be observed are, to arrange the workings in terraces, so as to facilitate the cut in g down of the earth; to transport the ores and the rubbish to their destination at the least possible expense ; and to gLd against the crumbling down of the sides. With the latter view they ought to have a suitable slope, or to be propped by timbers whenever they are not '^''ol^^wm-kings are employed for valuble clays, sands, as also for the alluvial soils of diamCds,^oldf and oxyde of tin, bog iron ores, &c., limestones, ^YP^un^s b;;^Wmf stones, roofin- slktes, masses of rock salt in some situations, and certain deposites of ores, partic- uCk the specular iron of the island of Elba; the masses of stanniferous granite of GaZ JlteZrTand Seyffen, in the Ertzgeberge, a chain of mountains between Saxony and^ Boifemk fhe thick veins or masses of black oxyde of iron of Nordmarch Danne- morar&cr^'^ Sweden; the mass of cupreous pyrites of Rieraas near Dronthemi in Norway ; several mines of iron, copper, and gold in the Ural mountams &c. slerranean workings may be conveniently d vided into five classes, viz :- 1. Veins, or beds, niuch incUned to the horizon, havmg a thickness of at least two ^"^'fieds of slight inclination, or nearly horizontal, the power or thickness of which does not exceed two yards. 3. Beds of great thickness, but slightly inclined. 4 Veins, of beds highly inclined, of great thickness. 5 Masses of considerable magnitude in all their dimensions. Subt^a^an mining requires two very distinct classes of workings; the preparatory, '^Tlle';:.^^^^^^^^^ in galleries, or in pits and gaUeries destined.to conduct the miner trthe point most proper for attacking the deposite of ore, for tracing it all round S^is ooint for preparing chambers of excavation, and for concerting neasures with a iS^wZhe cTrcEon of air, the discharge of waters, and the transport of the extracted "'If'the'vein or bed in question be placed in a mountain, and if its direction forms a very obtuse angle with the line of the slope, the miner begins by opening in its side, at the lowest possible level, a gallery of elongation, which serves at once to g've issue to the waters, to explore the deposite through a considerable extent, and then to follow it n another direction; but to commence the real mining operations, he pierces either shafts or galleries, according to the slope of the deposite, across the hrst gallery. For a stratum little inclined to the horizon, placed beneath a plain, the first thmg is to Pierce two vertical shafts, which are usually made to arrive at two points in the same Un^ of slope, and a gallery is driven to unite them. It is, m the first place, for the sake of circulatioi of air that these two pits are sunk; one of them which is also dest.n^ for the drainage of the waters, should reach the lowest point of the intended workings. MINES. 177 If a vein is intersected by transverse ones, the shafts are placed so as to follow, or, at least, to cut through the intersections. When the mineral ores lie m nearly VCTtical masses, it is right to avoid, as far as possible, sinking pits into their interior. These should rather be perforated atone side of their floor, even at some considerable distance, to avoid all risk of crumbling the ores into a heap of rubbish, and overu'helmmg the workmen. With a vein of less than two vards thick, as soon as the preparatory labors have brou<^ht the miners to the point of the vein from which the ulterior workings are to ramify, whenever a circulation of air has been secured, and an outlet to the water and the matters mined, the first object is to divide the mass of ore into large parallelopi- * peds, b\ means of oblong galleries, pierced 20 or 25 yards below one another, with pits of communication opened up, 30, 40, or 50 yards asunder, which follow the slope of the vein. These galleries and shafts are usually of the same breadth as the vein, unless when it is very narrow, in which case it is requisite to cut out a portion of the roof or the floor. Such workings serve at once the purposes of mining, by aflfording a portion of ore, and the complete investigation of the nature and riches of the vein, a certain extent of which is thus prepared before removing the cubical masses. It is proper to advance first of all, in this manner, to the greatest distance from the central point which can be mined with economy, and afterwards to remove the parallelopiped blocks, m work- ing back to that point. /. . • 1. This latter operation may be carried on in two different ways; of which one consists in attackins; the ore from above, and another from below. In either case, the excava- tions are disposed in steps similar lo a stair upon their upper or under side. The first is styled a vx)rking in direct or descending steps j and the second a working in reverse, or ascending steps. ^ . , , . , . *i. v • * i 1. Suppose, for example, that the post N,;ig. 941, included between the horizontal gallery a c and the shaft a b, is to be excavated by direct steps, a workman stationed upon a scaffi)ld at the point a, which forms the angle between the shaft and the elong- ated drift, attacks the rock in front of him and beneath his feet. Whenever he has cut out a parallelopiped (a rectangular mass), of from four to six yards broad, and two yards high, a second miner is set to work upon a scaffold at a', two yards beneath the first, who, in like manner, excavates the rock under his feet and before him. As soon as the second miner has removed a post of four or six yards in width, by two in height, a third begins upon a scaffold at a" to work out a third step. Thus, as many workmen are employed as there are steps to be made between the two oblong horizontal galleries which extend above and below the mass to be excavated ; and since they all proceed simultaneously, they continue working in similar positions, in floors, over each other, as upon a stair with very long wide steps. As they advance, the miners construct before them wooden floors c c c c, for the purpose of supporting the rubbish which each workman extracts from his own step. This floor, which should be very solid, serves also for wheeling out his barrow filled with ore. The round billets which sup- port the planks sustain the roof or the wall of the mineral vein or bed under operation. If the rubbish be very considerable, as is commonly the case, the floor planks are lost. However strongly they may be made, as they cannot be repaired, they sooner or later give way under the enormous pressure of the rubbish ; and as all the weight is borne by the roof of the oblong gallery underneath, this must be suffi- ciently timbered. By this ingenious plan, a great many miners may go to work toeether upon a vein without mutual interference ; as the portions which they detach have always two faces at least free, they are consequently more easily separable, either Vol. XL 12 178 MIKES. i If -J'! i ■it with gunpowder or with the pick. Should the vein be more than a yard thick, or ifiu substance be very refractor}', two miners are set upon each step, b bb b indicate the quadrangular masses that are cut out successively downwards ; and 1 1, 2 2, 3 3, for- wards ; the lines of small circles are the sections of the ends of the billets which support the floors. 2. To attack a mass y,Jig. 948, a scaffold m is erected in one of its terminal pits i> p, MINES. 17f at the level of the ceiling of the gallery r r', where it terminates below. A miner placed on this scaffold, cuts off at the angle of this mass a parallelopiped I, from one to two yards high, by six or eight long. When he has advanced thus far, there is placed in the same pit, upon another scaffold m'j a second miner, who attacks the vein above the roof of the first cutting, and hews down, above the parallelopiped 1, a paral- lelopiped of the same dimensions 1', while the first is taking out another 2, in advance of 1. When the second miner has gone forward 6 or 8 yards, a third is placed also in the same pit. He commences the third step, while the first two miners are pushing forwards theirs, and so in succession. In this mode of working, as weU as in the preceding, it is requisite to support the rubbish and the walls of the vein. For the first object, a single floor nnn, may be suf- ficient, constructed above the lower gallery, substantial enough to bear all the rubbish, as well as the miners. In certain cases, an arched roof may be substituted ; and in others, several floors are laid at different heights: The sides of the vein are supported by means of pieces of wood fixed between them perpendicularly to their planes. Some- times, in the middle of the rubbish, small pits are left at regular distances apart, through which the workmen throw the ore coarsely picked, down into the lower galler>'. The rubbish occasionally forms a slope///, so high that miners placed upon it can work conveniently. When the rich portions are so abundant as to leave too little rubbish to make such a sloping platform, the miners plant themselves upon moveable floors, which they carry forward along with the excavations. These two modes of working in the step-form, have peculiar advantages and disadvan- tages ; and each is preferred to the other according to circumstances. In the descending workings, or in direct steps', Jig. 714, the miner is placed on the very mass or substance of the vein ; he works commodiously before him ; he is not exposed to the splinters which may fly off from the roof; but by this plan he is obliged to employ a great deal of timber to sustain the rubbish ; and the wood is fixed for ever. In the ascending uorkings, or in reversed steps, Jig. 715, the miner is compelled to work in the re-entering angle formed between the roof and the front wall of his excavation, a posture sometimes oppressive ; but the weight of the ore conspires with his efforts to make it fall. He employs less timber than in the workings with direct steps. The sorU ing of the ore is more diflicult than in the descending working, because the rich ore is sometimes confounded with the heap of rubbish on which it falls. When seams of diluvium or gravel-mud occur on one of the sides of the vein, or on both, they render the quarrying of the ore more easy, by affording the means of uncover- ing the mass to be cut down, upon an additional face. Should the vein be very narrow, it is necessary to remove a portion of the sterile rock which encloses it, in order to give the work a sufficient width to enable the miner to ad- vance. If, in this case, the vein be quite distinct from the rock, the labor may be facili- tated, as well as the separation of the ore, by disengaging the vein, on one of its faces, through a certain extent, the rock being attacked separately. This operation is called stripping the vein. When it is thus uncovered, a shot of gunpowder is sufficient to detach a great mass of it, unmixed with sterile stones. By the methods now described, only those parallelopipeds are cut out, either in whole or in part, which present indications of richness adequate to yield a prospect of benefit. In other cases, it is enough to follow out the threads of ore which occur, by workings made in their direction. The miner, in searching within the crust of the earth for the riches which it concea's, IS exposed to many dangers. The rocks amidst which he digs are seldom or never entire, but are almost always traversed by clefts in various directions, so that impending frag- ments threaten to fall and crush him at every instant. He is even obliged at times to cut throus?h rotten friable rocks or alluvial loams. Fresh atmospheric air follows him with difficulty in the narrow channels which he lays open before him ; and the waters whicb circulate in the subterranean seams and fissures filter incessantly into his excavation, and tend to fill it. Let us now take a view of the means he employs to escape from these three classes of dangers. 1. 0/ the timbering of excavations. — The excavations of mines are divisible into three principal species ; shaftsy galleries, and chambers. When the width of these exca- vations is inconsiderable, as is commonly the case with shafts and galleries, their sides can sometimes stand upright of themselves ; but more frequently they require to be propped or stayed by billets of wood, or by walls built with bricks or stones ; or even by stuffing the space with rubbish. These three kinds of support are called timbering, toaliing, smd filling up. Timbering is most used. It varies in form for the three species of excavations, accord- ing to the solidity of the walls which it is destined to sustain. In a gallery, for example, it may be sufficient to support merely the roof, by means I f joists placed across, bearing at their two ends in the rock ; or the roof and the two walls by means of an upper joist s, fig. 949, which is then called a cap or cornice beam, resting on two lateral upright posts or stanchions, a 6, to which a slight inclination towards each other is given, so that they approach a little at the top, and rest entirely upon the floor. At times, only one of the walls and the roof need support. This case is of frequent occurrence in pipe veins. Pillars are then set up only on one side, and on the other the joists rest in holes of the rock. It may happeh that the floor of the gallery shall not be sufficiently firm to afford a sure foundation to the stand- ards ; and it may be necessary to make them rest on a horizontal piece called the sole. This is timbering with complete frames. The upright posts are usually set directly on the sole ; but the extremities of the cap or ceiling, and the upper ends of the standards, are mortised in such a manner that these cannot come nearer, whereby the cap shall possess its whole force of resistance. In fi iable and shivery rocks there is put behind these beams, both upon the ceiling and the sides, /acing boards, which are planks placed horizontally, or spars of cleft wood, set so close togecher as to leave no interval. They are called fascines in French. In ordinary ground, the miner puts up these planks in proportion as he goes forwards ; but in a loose soil, such as sand or gravel, he must mount them a little in advance. He then drives into the mass behind the wooden frame-work, thick but sharp-pointed planks or stakes, and which, in fact, form the sides of the cavity, which he proceeds to excavate. Their one extremity is thus supported by the earth in which it is thrust, and their other end by the last framing. Whenever the miner gets sufficiently on, he sustains the walls by t new frame. The size of the timber, as well as the distance between the frames or staiu chionsy depends on the degree of pressure to be resisted. When a gallery is to serve at once for several distinct purposes, a greater height is given to it ; and a flooring is laid on it at a certain level. If, for example, a gallery it to be employed, both for the transport of the ores and the discharge of the waters, a floor e e,fig. 715, is constructed above the bottom, over which the carriages are wheeled, and under which the waters are discharged. The timbering of shafts varies in form, as well as that of galleries, according to the nature and the locality of the ground which they traverse, and the purposes which they are meant to serve. The shafts intended to be stayed with timber are usually square or rectangular, because this form, in itself more convenient for the miner, renders the execution of the timbering more easy. The wood-work consists generally of rectangular frames, the spars of which are about eight inches in diameter, and placed at a distance asunder of from a yard to a yard and a half. The spars are never placed in contact, except when the pressure of the earth and the waters is very great. The pieces composing the frames are commonly united by a half-check, and the longer of the two pieces extends often beyond the angles, to be rested in the rock. Whether the shaft is vertical or inclined, the frame-work is always placed so that its plane may be perpendicular to the axis of the pit. It happens sometimes in inclined shafts that there are only two sides, or even a single one, which needs to be propped. These are stayed by means of cross beams, which rest at their two ends in the rock. When the frames 180 MINES. MINES. 181 l;l f' I; J- 1 'f do not touch one another, strong planks or stakes are fastened behind them to sustain the ground. To these planks the frames are firmly connected, so that they cannot slid p. In this case the whole timbering will be supported, when the lower frame is solidly fixed, or when the pieces from above pass by its angles to be abutted upon the ground. In the laige rectangular shafts, which serve at once for extracting the ores, for the dis- charge of the waters, and the descent of the workmen, the spaces destined for these sev- eral purposes are in general separated by paititions, which also serve to increase the strength of the timberings, by acting as buttresses to the planks in the long sides of the Crame-work. Occasionally a partition separates the ascending from the descending bas- ket, to prevent their jostling.— Lastly, particular passages are left for ventillation. As it is desirable that the wood shall retain its whole force, only those pieces are squared which absolutely require it. The spars of the frames in shafts and galleries arc deprived merely of their bark, which by holding moisture, would accelerate the decompo- sition of the wood. The alburnum of oak is also removed. Resinous woods, like the pine, last much shorter than the oak, the beech, and the cherry-tree ; though the larch is used with advantage. The oak has been known to last upwards of 40 years ; while the resinous woods decay frequently in 10. The fresher the air in mines, the more durable is the timbering. The marginal ^g». 950, 951 represent two vertical sections of a shaft, the one at right angles to the other, with the view of showing the mode of sustaining the walls of the excavation by timbering. It is copied from an actual mine in the Hartz. There we may observe the spaces allotted to the descent of the miners by ladders, to the drainage of the waters by pumps p, and rods /, and to the extraction of the mineral substances by the baskets B. a, by Cyfy ky fc, vavious cross timbers ; A, c, e, upright do. ; B, pump cistern ; v, w, corve-ways. The shafts here shown, are excavated in the line of the vein itself, — the rock enclosing it being seen in the second figure. In a great many mines it is found advantageous to support the excavations by brick or stone buildings, constructed either with or without mortar. These constructions are often more costly than wooden ones, but they last much longer, and need fewer repairs. They are employed instead of timberings, to support the walls and roof of galleries, to line the sides of shafts, and to bear up the roofs of excava- tions. Sometimes the two sides of a gallery are lined with ver- tical walls, and its roof is supported by an ogee vault, or an arch. If the sides of the mine are solid, a simple arch is sufficient to sustain the roof, and at other times the whole surface of a gallery is formed of a single elliptic vault, the great axis of which is vertical ; and the bottom is surmounted by a wooden plank, under which the waters run off; see fig. 951. ^ Walled shafts also are sometimes constructed in a circular or elliptic form, which is better adapted to resist the pressure of the earth and waters. Rectangular shafts of all dimensions, however, are frequently walled. -„. . , , • v vi.- ». The sides of an excavation may also be supported by filhng it completely with rubbish. Wherever the sides need to be supported for some time without the necessity of passing along them, it is often more economical to stuff them up with rubbish, than to keep up their supports. In the territory of Liege, for example, there have been shafts thus filled up for several centuries ; and which are found to be quite entire when they are emptied. The rubbish is also useful for forming roads among steep strata, for closing air-holes, and forming canals of ventilation. , j • Figs. 952, 953, 954 represent the principal kinds of mason-work employed in the gaUeries and shafts of mines. Fig. 955 exhibits the walling in of the cage of an over- shot water wheel, as mounted within a mine. Before beginning to build, an exca- vation large enough must be made in the gallery to leave a space three feet and a hatf high for the workmen to stand in, after the brick-work is completed. Between the two opposite sides, cross beams of wood must be fixed at certain distances, as chords of the vault, over which the rock must be hollowed out to receive the arch-stones, and the centring must then be placed, covered with deals to receive the voussoirsy beginning at the flanks and ending with the key-stone. When the vault is finished lhrou', so that between every- two there may be room enough to place three others, 6, c, b,fig. 962. From each of the cuts a, ore is procured by advancing with the help of timbering, till the roof t be reached. When this is done, these first cuts a, are filled up with rubbish, laid upon pieces of timber with which the ground is covered, so that if eventually it should be wished to mine underneath, no downfall of detritus is to be feared. These heaps of rubbish rise only to within a few inches of the top of the cuts a, in order that the working of the upper story may be easier, Ihe bed of ore being there already laid open upon its lower face. In proportion as the cuts a, oi the first story e f, are thus filled up, the greater part of the timbering is withdr\wn, and made use of elsewhere. The intermediate cuU b, c, 6, are next mined in like manner, either beginning with the cuts c, or the cuts 6, ac- cording to the localities. From fig. 962 it appears that the working may be so ar- tanged, that in case of necessity, there may be always between two cuts m activity the 961 ^ I f lis 7 ' . 184 MINES. *stanc€ of three cuts, either not made, or filled up with rubbish. Hence, alJ the portion of the bed of ore may be removed, which corresponds to a first story e Tfjig. 963, and thia portion is replaced by rubbish. 962 The exploration of the upper stories e' f', e2 f2, e3 f3, is now prepared in a similar manner; with which view shafts h hi, k fc3, are formed from below upwards in the wall m of the deposite, and from these shafts oblong galleries proceed, established successively on a level with the stories thus raised over one another. See Jig, 963. The following objects may be specified in the figures : — a a, the first cuts filled up with rubbish, upon the tirst story e Tyjig. 962. b b, other cuts subsequently filled up, upon the same story. e, the cut actually working. d, the front of the cut, or place of actual excavation of the mineral deposite. e, masses of the barren rock, reserved in the cutting, as pillars of safety. /, galleries, by means of which the workmen may turn round the mass e, in order to form, in the roof t, an excavation in the direction of the deposite. g, rubbish behind the mass e. k fc, two shafts leading from the first story e f, to the upper stories of the workint's as already stated. ^ ' wi, the wall, and / the roof of the mineral bed. In the second story e' f', the gallery of prolongation r', figs. 961 and 963 is not entirely perforated ; but it is further advanced than that of the third story, which, in its turn ia more than the gallery of the fourth. * From this arrangement there is produced upon j^g. 963 the general aspect of a workine by reversed steps. * Whenever the workings of the cuts c in the first story are finished, those of the second a' a', may be begun in the second ; and thus by mounting from story to story the whole deposite of ore may be taken out and replaced with rubbish. One great advanta'^e of this method is, that nothing is lost ; but it is not the only one. The facilities offered bv the system of cross vwrkings for disposing of the rubbish, most frequently a nuisance to the miner, and expensive to get rid of, the solidity Avhich it procures by the bankin" up the consequent economy of timbering, and saving of expense in the excavation of the rock reckoning from the second story, are so many important circumstances which recommend this mode of mining. Sometimes, indeed, rubbish may be wanted to fill up, but this may always be procured by a few accessory perforations ; it being easy to establish in the vicmity ol the workings a vast excavation in the form of a vault, or kind of subterraneous quarry, which may be allowed to fall in with proper precautions, and where rubbish will thus accumulate m a short time, at little cosL Fig. 964 represents a section of the celebrated lead mines of Bleyberg in Carinthia. not far from Villach. ^ =• i "• 6, c, is the ridge of the mountains of compact limestone, in whose bosom the wonanes arc carried on. ° t is the metalliferous valley, running from east to west, between the two pareUel MINES. 186 valleys of the Gail and the Drave, but at a level considerably above the waters of these "7Tis the direction of a great many vertical beds of metalliferous limestone, ■of considering the direction and dip of the marly schist, and ""-^'"'"f'™"' '^^^J'",^ m the space lo, to, to me wesi oi Qg. ^^^^ ' the line 1, », it would appear that .>^^^^>^ ^ ^j.p^j portion of this system of mountains has suffered a slip between 1, s, and a parallel one towards the east; whereby, probably, that ver- tical position of the strata has been produced, which exists through a considerable extent. The metallifer- ous limestone is covered to a certain thickness with a marly schist, and other more recent rocks. It is in this schist that the fine marble known under the name of the luviachello of Bleyberg is quarried. The -alena occurs in the bosom of this rock in flattened masses, or Wocks of a con- siderabfe vXme, which are not separated from the rest of the calcareous beds by any seam It is accompanied by zinc ore icalamm), especially in the upper parts of the "^Tver^l of the workable masses are indicated by r, r3; each presents itself as a solid analoc^ous to a very elongated ellipse, whose axis dips, not according to the mc ina- S>n of theCrounding rock, but to an oblique or intermediate line be^wf en this inclina- tion, and the direction of the beds of limestone ; as shown by r w r u. E% er> th ng Sates the contemporaneous formation of the limestone, and the lying beds of the ^' Thraccidents or faults called kluft (rent) at Bleyberg are visible on the surface of the ground. Experienced miners have remarked that the rich masses occur more frequently in the direction of these accidents than elsewhere. , ^ ^ ^ . . „. jiffv. It is in general by galleries cut horizontally in the bcnly of the mountain, and at differ- ent levels », g, ^U that the miner advances towards the masses of ore r, rz. Many of these ganeries^kr'e 500 fathoms long before they reach ^ ^^'^kable mass TJie sev^^^ galleries are placed in communication by a few shafts, such as <; but few oi these are sunk deeper than the level of the valley c. ^^ , n i * .i.^ The tLl length of the mines of Bleyberg is about 10,000 yards, parallel to the vallev 6 . in which space there are 500 concessions granted by the govern men to various individuals or joint stock societies, either by themselves or associated with the govern- "" The metalliferous valley contains 5000 inhabitants, all deriving subsistence from the mines ; 300 of whom are occupied in the government works. t^„,.v„„, ncw«w; Each concession has a number and a name ; as Antoni, Christoph, Matthseus, Oswaldi, ^' F«g. ^t'is a section in the quicksilver mine of Idria. 1. is the gray limestone ; 2. is a blackish slate ; 5. is a grayish slate. Immediately above these transition rocks lies the bed containing the ores called corallenerz, which consist of an intimate mixture of sul- phuret of mercury and argillaceous Umestone ; in which four men can cut out, m a month, 2J toises cube of rock. 965 Fig. 966 represents a section of part of the copper mine of Mansfeldt ; containing the cellular limestone, called rauchwacke, al- ways with the compact marl-Iimo- stone called zechstein ; the cupre- ous schist, or kupferschiefer; the wall of grayish-white sandstone, called the weisse liesende ; and the wall of red sandstone, or the rolhelie gende. The thin dotted stratum at top is vegetable mould ; the laree dotted portion to the right of the figure is oolite ; the vein at its side is sand ; next is rauchwacke ; and lastly, the main body of fetid limestone^ or stinkstein. II 186 MINES. Fig. 967 represents one of the Mansfeldt copper schist mines in the diitrict called Burgoerner, or Preusshoheit. 1. Vegetable mould, with silicious gravel. 2. Ferruginous clay or loam. 3. Sand, with fragments of quartz. 4. Red clay, a bed of variable thickness as well as the lower strata, according as the cupreous schist is nearer or farther from the surface. 5. Ooolite iroogenstein). 6. Newer variegated sandstone (hunter sandstcin), 7. Newer gypsum ; below which, there is 8. A bluish marly clay. 9. Slinkstone, or lucullite. 10. Friable grayish marl. 11. Older gypsum, a rock totally wanting in the other district? of the mines of Kothen- berg ; but abounding in Saxon Mansfeldt, where it includes vast caverns known among the miners by the name of schlotten, as indicated in the figure. 12. The calcareous rock called zechstein. The lower part of this stratum shows symptoms of the cupriferous schist that lies underneath. It presents three thin bands, differently modified, which the miner distinguishes as he descends by the names of Ihe Sterile or rotten {fault) rock; the roof (dachklotz) ; and the main rock {oberberg.) yo8 13. Is a bed of cupriferous schist (kupferschiefer), also called the bitumino-marly schist, in which may be noted, in going down, but not marked in the figure : — a, the lochberg, a seam 4 inches thick. by the kammschale, | of an inch thick. c, the kop/schakf one inch thick. These seams are not worth smelting ; the following, however, are :— d, the schiefer kopf, the main copper schist, 2 inches thick. e, a layer called locherij one inch thick. 14. The wall of sandstone, resting upon a porphyry. Fig. 968 is a section of the mines of Kiegelsdorf in Hessia, presenting — 1. Vegetable mould. 2. Limestone distinctly stratified, frequently of a yellowish color, called lagerha/ter kalkstein. 3. Clay, sometimes red, sometimes blue, sometimes a mixture of red, blue, and yellow. 4. The cellular limestone (rauhkalk). This rock dififers both in nature and position from the rock of the same name at Mansfeldt. 5. Clay, usually red, containing veins of white gypsum, and fine crystals of sele- nite. 6. Massive gypsum of recent formation. 7. Fetid limestone, compact and blackish gray, or cellular and yellowish gray. 8. Pulverulent limestone, with solid fragments interspersed. 9. Compact marl-limestone, or zechstein, which changes from a brownish color above to a blackish schist below, as it comes nearer the cupreous schist, which seems to form a part of it. 10. Cupreous schist (kupferscniefer), of which the bottom portion, from 4 to 6 inches thick, is that selected for metallurgic operations. Beneath it, is found the usual wall or bed of sandstone. A vein of cobalt ore «, which is rich only in the grayish- white sand- stone {weisse liegende), traverses and deranges all the beds wherever it comes. 0/ working mines by fire. — The celebrated mine worked since the tenth century in Uie mountain called Rammelsberg, in the Hartz, to the south of Goslar, presents a strar MINES. 187 tificd mass of ores, among the beds of the rock which constitute that mountam. The mineral deposite is situated in the earth, like an enormous mverted wedge, so ^ * „i« thickness (power), inconsiderable near the surface of the ground, mcreases as it descends. At about 100 yards from its outcrop, reckoning in the direction of the slope oi me ae- posite, it is divided into two portions or branches, which are separated Irom eacn omer, throughout the whole known depth, by a mass of very hard clay slate, which passes into flinty slate. The substances composing the workable mass are copper and iron pjriies with sulphuret of lead (galena), accompanied by quartz, carbonate of lane, compact sul- phate of baryta, and sometimes gray copper ore, sulphuret of zinc, and arsenical pyriie. The ores of lead and copper contain silver and gold, but in small proportion, particularly as to the last. . . _ , j- -j j „.„«.,« A mine so ancient as that of Rammelsberg, and which was formerly divided among several adventurous companies, cannot fail to present a great many shafts and excava- tions ; but out of the 15 pits, only two are employed for the present workings ; namely, those marked a b and e f, in fig. 969, by which the whole extraction and drainage are executed. The general system of exploitation by fire, as practised in this mine, consists of the following operations : — 1 An advance is made towards the deposites of ore, successively at diflferent levels, by transverse galleries which proceed from the shaft of extraction, and terminate at the wall of the stratiform mass. ... /• i. u 2. There is formed in the level to be worked, large vaults in the heart of the ore, by means of fire, as we shall presently describe. ^ j r 4», kk-.i. 3. The floor of these vaults is raised up by means of terraces formed from the rubbisn, in proportion as the roof is scooped out. , .. j 4. The ores detached by the fire from their bed, are picked and gathered ; sometime* the larger blocks are blasted with gunpowder. ^ ^ ,. «. r * .• a 5. Lastly, the ores thus obtained are wheeled towards the shaft of extraction, and turned out to the day. , . j • ^i. * • i . . ^«„ Let us now see how the excavation by fire is practised ; and m that view, let us con- sider the state of the workings in the mines of Rammelsberg in 1809. We may remark in fie 969 the re^^ulariiy of the vaults previously scooped out above the level b c, and the other vaults which are in full activity of operation. It is, therefore, towards the lower levels that the new workings must be directed. For this purpose, the transverse gallery being alreadv completed, there is prepared on the first of these floors a vault of exploitation at 6, which eventually is to become similar to those of the superior levels. At the same time, there is commenced at the starting point below it, reached by a smaU well dug in the line of the mineral deposite, a transverse gallery m the rock, by means of biastino' with gunpowder. The rock is also attacked at the starting-point by a similar cut, which advances to meet the first perforation. In this way, whenever the vaults of the level c are exhausted of ore and terraced up with rubbish, those of the level beneath it will be in full activity. . . Others will then be prepared at a lower level; and the exploitation may afterwards t>e driven below this level by pursuing the same plan, by which the actual depth of excava- tion has been sained. In workings by fire we must distinguish, 1. The case where it is neecessan' to open a vault immediately from the floor ; 2. The case where the vault having already a certain elevation, it is necessary to heighten its roof In the former case, the wall or floor of the mineral deposite is first penetrated by blasting with gunpowder. As soon as th'S penetration is eflected over a certain length, parallel to the direction of the future vault, as happens at 6, there is arranged on the bottom a horizontal layer of billets of firwood, over which other billets are piled in nearly a vertical position, which rest upon the ore, so that the flame in its expansion comes to play against the mineral mass to be [I- a .r^ i- •-"I I' 188 MINES. detached. Wlien after some similar operations, the flame of the pile can no longer reach the ore of the roof on account of its height, a small terrace of rubbish must be raised on the floor of the deposite ; and over this terrace, a new pile of fagots is to be heaped up as above described. The ancient miners committed the fault of constantly placing such terraces close to the roof, and consequently arranging the fagots against this portion of the ore, so that the flame circulated from the roof down to the floor. The result of such procedure was the weakening of the roof, and the loss of much of the ore which could not be extracted from so unstable a fabric ; and besides, much more wood was burned than at the present day, because the action of the flame was dissipated in part against the whole mass of the roof, instead of being concentred on the portion of the ore which it was desired to dislodge. Now, the flame is usually made to circulate from the floor to the roof, in commencing a new vault. When the vault has already a certain height, care is always taken that between the roof of the vault and the rubbish on which the pile is arranged, no more than two yards of space should intervene, in order that the flame may embrace equally the whole con- cavity of the vault, and produce a uniform effect on all its parts. Here, the pile is formed of horizontal beds, disposed crosswise above one another, and presents four free vertical faces, whence it has been called a chest by the miners. It is usually on Saturday that the fire is applied to all the piles of fagots distributed through the course of the week. Those in the upper floors of exploitation are first burned, in order that the inferior piles may not obstruct, by their vitiated air, the com- bustion of the former. Thus, at 4 o'clock in the morning, the fires are kindled in the upper ranges ; from pile to pile, the fireman and his assistant descend towards the lower floors, which occupies them till 3 o'clock in the afternoon. Vainly should we endeavor to describe the majestic and terrific spectacle which the fire presents, as it unfolds its winjjs under its metallic vaults, soon filled with vast volumes of smoke and flame. Let us mark the useful effiect which it produces. When the flame has beat for a few instants on the beds of ore, a strong odor of sulphur, and sometimes of arsenic is perceived ; and soon thereafter loud detonations are heard in the vaults. Suddenly the flame is seen to assume a blue color, or even a white ; and at this period, after a slight explosion, flakes of the ore, of greater or less magnitude, usually fall down on the fire, but the chief portion of the heated mineral still remains fixed to the vault. The ores pass now into a shattered and divided condition, which allows them afterwards to be detached by long forks of iron. In this manner the fire, volatilizing entirely some principles, such as sulphur, zinc, arsenic, and water, changing the aggregation of the constituent parts of the ore, and causing fissures by their unequal expansibilities, facilitates the excavation of such materials as resist by their tenacity the action of gunpowder. The combustion goes on without any person entering the mine from Saturday even- ing till Monday morning, on which day, the fireman and his assistants proceed to extinguish the remains of the bonfires. On Monday also some piles are constructed in the parts where the effect of the former ones has been incomplete ; and they are kindled after the workmen have quitted, the mine. On Tuesday all hands are employed in detaching the ores, in sorting them, taking them out, and preparing new piles against the next Saturday. The labor of a week consists for every man of five posts during the day, each of 8 hours, and of one post of four hours for Saturday. Moreover, an extra allowance is made to such workmen as employ themselves some posts during the night. The labor of one compartment or atelier of the mine consists therefore in arranging the fagots, in detaching the ore which has already experienced the action of the fire, i» breaking the blocks obtained, in separating the ore from the debris of the pile, and, whenever it may be practicable or useful, in boring holes for blasting with gunpowder. The heat is so great in this kind of mine, that the men are obliged to work in it without dothing. We have already remarked, that besides the working by fire, which is chiefly used here, recourse is sometimes had to blasting by gunpowder. This is done in order either to re- cover the bottom part or ground of the vaults on which the fire can act but imperfectly, to clear away some projections which would interfere with the effect of the pile, or lastly to strip the surrounding rock from the mass of the ore, and thence to obtain schist proper for the construction of the rubbish-terraces. The blasting process is employed when the foremen of the workshop or mine- chamber judge that a hole well placed may separate enough of ore to pay the time, the repair of tools, and the gunpowder expended. But this indemnification is raiely obtain- ed. The following statement will give an idea of the tenacity which the mineral deposite often presents. In 1808, in a portion of the Rammelsberg mine, the ore, consisting of txtremely com- pact iron and copper pyrites, was attacked by a single man, who bored a mining hole. MINES. 189 Afto, 11 «n«t, nf obstinate labor, occupying altogether 88 hours, the workman, being ^•1 1 ^IrrntpS had been able to advance the hole to a depth of no more than vigilant y ^»PJ"^^/Xh he had rendered entirely unserviceable 126 punches or borers, tS s'ie" ht^'wL'^^^^^^^^ been re-tipped with V and 201 which ha be harp- ened; 6i pounds of oil had ^^.^-^^l^^;: 'TlsTo^Tr^rt ^c2^nt^^ ^^^Zi::.:^^^^^^^^^ n^lnes, ^J^^I<^ee, of this hole cost, ereat weret^ch Ss a^ and dearer than it still is at Rammelsberg, inining by great, ^f f\™"r" '^^* , .^ ._^_y o^her mode of exploitation. It is even certain, that fire would be Ffff^J^^^'^Xv^^ero^^ not be practicable for every on any-^ f ^PP^^^'^^^'^^^P -f fudcame to fail, it would be requisite to renounce the ^l!l:':rZ^r.%:k%^^^^ -untam still contains a large quantity of "^^i. all mii^s the n^ci^tiori of t b. - ^^^^^ JJ^^ j^^^ m^d^^? "^"'/ r^tnn^^Z^r^fZ^^^^^ the a"r at n2^ Fahr., when the workmen return f„?n ifarrX HLst^^^^^ the piles, and in which besides it is necessary that this into It ^.tter the comDusiiu^^ activity in their absence. But in consequence of the extent Tnf mS mmS^^^^^^ the number of the shafts, galleries, and thdr Srffprences cfTvel the ventilation of the mine is in a manner spontaneously maintained. tS^S temperature is peculiarly favorable to it. The aid of art consists merely in 5tLf some do^rs jUci^ which may be opened or shut at pleasure, to carry on '''ln"itlJ"eL'^''he''Rammelsberg from its summit, which rises about 400 yarfs in consiaerino i"f ^* oh^enre fir^t. beds of slaty sandstone, which become the above the town ^^ fosla^^^f^^^ surfacl At aboit 160 yards below Srton leve/t^^^^^^^^ l^^om of the slaty graywacke, a powerful stratum of IhPlls [mnasted fn a fS^^^^ sandstone. See d, fig- 963. In descending to^.-ards the Shells impasted in a lerrugmoua^^^ ^^ ^^^ ^^^^ ^^^ ^^re^M stratification of the clay-slate which forms its walls and roof grows more and more manifest. Here the slate is black, compact, and thinly foliated. The inclination of the difterent beds of rock is indicated at b. The substance of the workable mass is copper and iron pyrites, along with sulphuret of lead, accompanied by quartz, carbonate of lime, compact sul- phate of baryta, and occasionally gray copper i/ahlerz), sulphuret of zinc, and arsenical pyrites. The ores are argentiferous and auriferous, but very slightly so, especially as to the gold. It is the ores of lea'd and copper which contain the silver, and m the latter the gold is found, but without its being well ascertained in what mineral it is deposited. Sometimes the copper occurs in the native state, or as copper of cementation. Beautiful crystals of sulphate of lime are found in the old workings. . , In figs. 969. 970, A b is the shaft of extraction, called the Kahnenkuhler ; N is the ventilation shaft, called BreiU lingerwetterschacht ; p is th3 extraction shaft, called Innier- E F, is a new extraction-shaft, called Neuer treibschacht, bv which also the water is pumped up ; by a b, and e r. the whole extraction and draining are carried on. The ores are raised in these shafts to the level of the wagon- gallery (galerie de roulage) t, by the whims 1, q, provided with ropes and buckets. 1, 2, 3, 4, fig, 969, represent the positions of four water-wheels for working the whims; the first two being employed in extracting the ores, the last two in draining. The driving stream is led to the wheel 1, along the drift I ; whence it falls in succession upon the wheds 2, 3, 4. The general system of working consists of the followmg operation : — ... i^___^k 1. The bed of ore is got at by the transverse galleries, m, n, o, rse wtuiu 192 MnvTT. MINES. ii 193 Mill terranean cavUies a continual circulation of air, which may renew the atmosphere round the miners. The whole of the means employed to produce this eflect, constitutes what IS called the ventilation of mines. These means are divided into natural and artificial. The natural means are the cur. rents produced by the difference of density between the air of mines and the external air ; the artijirtal are air-exhausters or condensers, fires, &c. The temperature of the air of the subterranean workings surpasses the mean tem- perature of the place in which the mine is opened. Hence it is lighter in winter, but m summer often heavier than the air of the atmosphere. For this reason, when the mine presents two openings at different 'evels, the air naturally flows out by the most elevated in winter, and by the lowest in summer. We may take advanta<^e of this circumstance, to lead the air into the bottom of even a very long gallery, opening into ine sideol the mountain, by piercing a shaft into its roof at some distance from the entrance, and dividing the gallery by a horizontal floor into two parts, which have no mutual communication, except at the furthest extremity— the upper part communica- tmg with the shaft, and the under with the mouth of the gallery. If the two compart- ments have different dimensions, the air in the smaller sooner comes into an equilibrium of temperature with the rock ; and the ditierence of temperature of the two compart- ments is sufficient to produce a current. If a streamlet of water flows through this gallery, it facilitates the flow of the air along the lower compartment. If a mine has several openings situated on the same level, it rarely happens but some peculiar circum- stance destroys, during the colds of winter and the heats of summer, the equilibrium of the air. But m spring and autumn, when the external air is nearly of the same tem- perature with that of tlie mines, the above-named causes are almost always too feeble to excite an issuing current. This effect is, however, frequently obtained by raising over one of the shafts a chimney 20 or 30 yards high, which alone produces the eflect of an opening at a different level. It has been remarked that stormy weather usually deran^'es every system of ventilation. See Pitcoal and Ventilation. ^ MINES, BLASTING. It has been often noticed that since the application of gun- powder for blasting, few if any improvements have been made in the methods adopted lor cutting through hard rocks ; and the great expense of maintaining engine powei for pumping and winding during the long period required to sink shafts through such rocks has been, and still is the sole cause of some of the best and richest tracts oJ minerals in Oreat Britain lying idle and unproductive, and has been the principal cause of the loss of lite so serious and often occurring from explosion in mines. The improvements, or rather the new system now intix)duced, will be better under- stood alter a review of the methods and tools heretofore used. The oldest method of pumping, or taking up the water from the bottom of the shaft during sinking was the Hogar pipe; this was about 4 feet in length, made of leather, and stiffened by rings of metal : the constant damage this was liable to in blasting caused it to be almost abandoned, and in its place the stock and slide pipe was intro- duced. This consists of two cast-iron pipes sliding into each other as a telescope and kept tight m the joint by a stuflfing-box; this contrivance is not only expensive in first cost, but liable to breakage and heavy to handle. Both these modes of pumping are subject to a still greater defect; the pump can only be made nearly under the pump trees, so that during a long time of the sinking it often occurs that only two or three men can be effectually emplo\'ed in the shaft; this in some of the large shafts (say on a common size used in South Wales, 18 feet by 10 feet) causes serious delay in the pro- gress of the work. ^ In boring it has been customary to use a borer, the body of which was ma'de ot wrought iron, and the bit or end of the borer of shear steel welded on the iron. No attempts appear ever to have been made to fix any definite proportion between the size of the stock or handle and the breadth of the bit ; and from this cause a very great portion of the power of the striker has been uselessly expended. The use of cast steel borers is, in some respects, entirely new as applied to mining, and by the superior hardness of cast steel as compared with shear steel, greatly expS* dites the process of boring and saves expense; they have also an advantage in trans mitting the force of the hammer to the bit, on account of their stiffness or rigidity and further to prevent loss of power, it is of importance that the bit should be so pnv portioned to the handle or stock as to work freely in the bore-hole, and at the same time spring or bend as little as possible under the blow of the hammer. The following proportions appear to answer these conditions. (See top of next page.) The suction pipe now used by the exhibitor, about 20 feet in length, is made of gutto percha, and supersedes the use of the leather Hogar, and the stock and slide ; it is not bable to accident, and can be repaired easily ; it enables the pump slide to be made in any part of the shafts and a greater number of men to work it in the shaft at one time. Diameter of Octagon Cast SteeL 1 inch. 1* H »» »» *t Breadth of the face of Bit. 1| inch. H « 2 2i 2* „ TTie introduction of electricity as the power for blasting in connection with the improvements before explained, may be said to constitute a new era in the history of mining. The apparatus at present used for blasting is Grove's battery of 6 inches square : this is placed in some convenient position near the top of the shaft ; two copper wires, coated with gutta percha, are carried down the shafts, and these are connected with the other wires inserted in a small cartridge which is placed in the charge of powder for blasting. MINES. The miner, in sinking into the earth, soon opens up numerous springs, whose waters, percolating into the excavations which he digs, constitutes one of the greatest obstacles that nature opposes to his toils. When his workings are above the level of some valley and at no great distance, it is possible to get rid of the waters by leading them along a trench or a gallery of efflux. This forms always the surest means of drainage ; and notwithstanding the great outlay which it involves, it is often the most economical. The great advantages accruing from these galleries, lead to their being always estab- lished, and without risk, in mines which promise a long continuance. There are many galleries several leagues in length ; and sometimes they are so contrived as to discharge the waters of several mines, as may be seen in the environs of Fieyberg. Merely such a slope should be given them as is barely sufficient to make the water run, at the ut- most from Tj-i— to Jo o> ^^ ^^ ^^ drain the mine at the lowest possible level. Whenever the workings are driven below the natural means of drainage, or below the level of the plain, recourse must be had to mechanical aids. In the first place, the quantity of percolating water is diminished as much as possible by planking, walling, or calking up with the greatest possible care those pits and excavations which traverse the water levels ; and the lower workings are so arranged that all the waters may unite into wells placed at the bottom of the shafts or inclined galleries ; whence they may be pumped up to the day, or to the level of the gallery of efflux. In most mines, simple sucking pumps are employed, because they are less subject to give way, and more easy of repair ; and as many of these are placed over each other, as the shaft is ten yards deep, below the point where the waters have a natural run. These draining machines are set in motion by that mechanical poWer which happens to be the least costly in the place where they are established. In almost the whole of England, and over most of the coal-mines of France and Silesia, the work is done by steam-engines ; in the principal metallic mines of France, and in almost the whole of Germany and Hungary, by hydraulic machines ; and in other places, by machines moved by horses, oxen, or even by men. If it be requisite to lift the waters merely to the level of a gallery of efflux, advantage may be derived from the waters of the upper parts of the mine, or even from waters turned in from the surface, in establishing in the mine of the gallery-level, water-pressure machines, or overshot water-wheels, for pump- ing up the lower water. This method is employed with success in several mines of Hungary, Bohemia, Germany, Derbyshire, Cornwall, in those of Poullaouen in Brittany, &c. It has been remarked, however, that the copious springs are found rather toward the surface of the soil than in the greatest depths. TRANSPORT OF ORES TO THE SURFACE. The ore being extracted from its bed, and having undergone, when requisite, a first sorting, it becomes necessary to bring it to the day, an operation performed in different ways according to circumstances and localities, but too often according to a blind routine. There are mines at the present day, where the interior transport of ores is executed on the backs of men; a practice the most disadvantageous possible, but which is gradually wearing out. The carriage along galleries is usually effected by means of hurdles, barrows, or, still better, by little wagons. These consist of frames resting on four wheels ; two larger, which are placed a little behind the centre of gravity, and two smaller, placed before it. When this carriage is at rest, it bears on its four wheels, and leans forward. But when the miner, in pushing it before him, rests on its posterior border, he makes it horizontal; in which case it rolls only upon the two larger wheels. Thus, the friction due to four wheels is avoided, and the roller or driver bears no part of the burden, as he would do with ordinary wheelbarrows. To ease the draught still more, two parallel rails of wood or iron are laid along the floor of the gallery, to which Vol. U. 13 194 MINES. MINES. 195 a ;- the wheels of the carriage are adjusted. It is especially in metallic mines, where the ore is heavy, and the galleries straight, that these peculiar wagons are employed. In coal mines, carriages formed with a much larger basket, borne on a railroad by four equal wheels, are preferred. Sometimes the above wain, called on the Continent a dog (chicn), is merely a simple frame on four wheels, on which a basket is set. In the great mines, such as many of the coal and salt mines of Great Britain, the salt mines of Galhcia, the copper mines of Fahlun, the lead mines of Alston-Moor, horses and asses are mtroduced into the workings to drag heavier wagons, or rather a train of wagons attached to one anolhtr. These animals often live many years under ground, without ever revisit- ing the light of day. In other mines, such as those of Worsley, in Lancashire, subter- ranean canals are cut, upon which the ore is transported in boats. When the workings of a mine are beginning, when they are still of little depth, and employ few hands, it is sufficient to place over the shaft a simple wheel and axle, by means of which a few men may raise the water-pails, and the baskets or tubs filled with ore ; but this method becomes soon inadequate, and should be replaced by more power- ful machines. ACCESSORY DETAILS. Few mines can be penetrated entirely by means of galleries. More usually there are shafts for mounting and descending. In the pits of many rc.nes, the work- men go down and come up by means of the machines which serve to elevate the ores. In several mines of Mexico, and the north of Europe, pieces of wood, hxed on each side of the pit, form the rude steps of a ladder by which the workmen pass up and down. In other mines, steps are cut in the rock or the ore ; as in the quicksilver mines of Idria and the Palatinate, in the salt mines of Wieliczka, and in some ot the silver mines of Mexico. In the kist they serve for the transport of the ore, which is carried up on men's backs. Lastly, certain mines are entered by means of slopes, some of which have an inclination of more than 30^. The workmen sbde down these on a kind of sledge, whose velocity of descent they regulate by a cord hrmly faxed at the upper end. , ,, . , r /v Miners derive light from candles or lamps. They carry the candles m a lump of soft clay, or in a kind of socket terminated by an iron point, which serves to fix it to the rock, or to the timbering. The lamps are made of iron, hermetically closed, and suspended, so that thev can not droop, or invert and spill the oil. They are usually hun«' on the thumb bv a hook. Miners also employ small lanterns, suspended to their eirdles. Many precautions and much experience are requisite to enable them to carry these lights in a current of air, or in a vitiated atmosphere. It is especially in coal mines liable to the disengagement of carburetted hydrogen, that measures of safety are indispensable a-ainst the explosions. The appearance of any halo round the flame should be carefully watched as indicating danger; and the lights should be carried near the bottom of the gallery. The great protector against these deplorable accidents, is the safety lamp. See Lamp of Davy. We can not conclude this general outline of the working of mines, without giving some account of the miners. Most men have a horror at the idea of biirymg them- selves, even for a short period, in these gloomy recesses of the earth. Hence mining operations were at first so much dreaded, Ihat, among the ancients, they were assigned to slaves as the punishment of their crimes. This dislike has diminished with the im- provements made in mining; and finally, a profitable and respected species of labor has given mining its proper rank among the other departments of industry. The espnt de corps, so conspicuous among seamen, has also arisen among miners, and has given dignity to their body. Like every society of men engaged in perilous enterprises, and cherishing the hopes of great success, miners get attached to their profession, talk of it with pride, and eventually in their old age regard other occupations with contempt. They form, in certain countries, such as Germany and Sweden, a body legally consti- tuted, which enjovs considerable privileges. Miners work usually 6 or 8 hours at a time. This period is called a journey {posie, in French). . . .u Miners wear, in general, a peculiar dress, the purpose of which is to protect them, as much as possible, from the annoyances caused by water, mud, and sharp stones, which occur in the places where they work. One of the most essential parts of the dress of a German miner is an apron of leather fitted on behind, so as to protect them in sitting on moisture or angular rubbish. In England, the miners wear nothing but flannels; though they frequently strip off all their clothes except their trowsers. In many coun- tries the mallet and the pick, or pointeroUe (called m German Schegel and £t.cn), dis- posed in a Saint Andrew's cross, are the badge of mmers, and are engraved on their buttons, and on everything belonging to mines. * ♦!,„„ ^„u „ Several of the enterprises executed in mines, or in subserviency to them, merit a distinguished rank among the history of human labors. Several mines are worked to a depth of more than 600 yards, some even to a thousand yards below the surlace ol me soil. A great many descend beneath the level of the ocean ; and a few even extend under its billows, and are separated from them by a thin partition of rock, which allows their noise, and the rolling of the pebbles, to be heard. In 1792, there was opened, at Valenciana, in Mexico, an octagonal pit, fully 7| yards wide, destined to have a depth of 560 yards, to occupy 23 years in digging, and to cost 240,000/. The great drainage gallery of the mines of Clausthal, in the Hartz, is 1 1,377 yards, or six and a half miles long, and passes upward of 300 yards below the church of Clausthal. Its excavation lasted from the year 1777 till 1800, and cost about 66,000/. Several other galleries of efllux might also be adduced, as remarkable for their great length and expense of formation. The coal and iron mines subservient to the iron works of Mr. Crawshay, at Merthyr- Tydvil, in Wales, have given birth to the establishment, interiorly and above ground, of iron railways, whose total length, many years ago, was upward of 100 English miles. The carriage of the coal extracted from the mines in the neighborhood of Newcastle to their points of embarkation, is executed almost entirely, both under ground and on the surface, on iron railways, possessing an extent of upward of 500 miles. There is no species of labor which calls for so great a development of power as that of mines; and accordingly, it may be doubted if man has ever constructed machines so powerful as those which are now employed for the working of some mineral excavations. The waters of several mines of Cornwall are pumped out by means of steam-engines, whose force is equivalent in some instances to the simultaneous action of many hundred horses. Mines, General Summary of. Mines maybe divided into three great classes : 1. Mines in the gealogical formations anterior to the coal strata; 2. Mines in the secondary formations ; 3. Mines in alluvial districts. The first are opened, for the most part, upon veins, masses, and metalliferous beds. The second, on strata of combustibles, as coal ; and metalliferous or saliferous beds. The last, on deposites of metallic ores, disseminated in clays, sands, and other alinvial matters, usually superior to the chalk ; and even of far more recent formation. The mines of these three classes, placed, for the most part in very diflferent physical localities, differ no less relatively to the mode of working them, and their mechanical treatment, than in a gealogical point of view. MINES OF FORMATIONS ANTERIOR TO THE COAL, These mines are situated in a few mountainous regions, and their whole amount forms but a small portion of the surface of the earth. The most remarkable of these are^ the Cordilleras of South America; the mountains of Hungary ; the Altayan mountains; the Ural mountains ; the Vosges and the Black Forest; the Hartz, and the east of Germany ; the centre of France ; the north of Portugal, and the adjacent portions of Spain ; Britanny ; the corresponding coasts of Great Britain and Ireland ; the north of Europe ; the Allegany chain ; the south of Spain ; the Pyrenees ; the Alps ; the schistose districts on the banks of the Rhine and the Ardennes ; the calcareous mountains of England and of Daouria. MINES OF THE CORDILLERAS OF SOUTH AlVIERICA. Few regions are so celebrated for their mineral wealth as the great chain which, under the name of the Cordillera of the Andes, skirts the shores of the Pacific ocean, from the land of the Patagonians to near the northwest point of the American continent. Who has not heard of the mines of Mexico and Potosi ? The mineral wealth of Peru has passed into a proverb. The most important mines of the Cordilleras are those of silver ; but several of gold, mercury, copper, and lead, have likewise been opened. These mountains are not equally metalliferous in their whole extent. The workings occur associated in a small number of districts far distant from each other. In the Andes of Chili, particularly in the province of Coquimbo, some silver mines are explored, which afford chiefly ores of an earthy or ferruginous nature, mingled with imperceptible portions of ores with a silver base, known thereunder the name of Pacos. The same province also presents copper mines of considerable importance, from which are extracted native copper, orange oxide of copper, carbonate of copper (malachite), and copper pyrites, associated with some muriate of copper. In a few mines, masses of native copper of extraordinary magnitude have been found. The second metalliferous region of the Andes occurs between the 21st and 15th Jegrees\)f south latitude. It includes the celebrated mountain of Potosi, situated in 196 MINES. MINES. m iii'i 11 !l LA' I 11- nearly the 20th degree of south latitude, on the eastern slope of the chain, and stveral other districts, likewise very rich, which extend principally toward the northwest, as far as the two banks of the lake Titicaca, and even beyond it, through a total length of nearly 150 leagues. All these districts, which formerly depended on Peru, were united in 1778 to the government of Buenos Ayres. The mines of Potosi were discovered in 1545, and have famished since that period till our days, a body of silver which M. Hum- boldt values at 230,000,000Z. sterling. The first years were the most productive. At that time ores were often found which afforded from 40 to 45 per cent, of silver. Since the beginning of the eighteenth century, the average richness of the ore does not exceed above from 3 to 4 parts in 10,000. These ores are therefore very poor at the present day ; they have diminished in richness in proportion as the excavations have become deeper. But the total product of the mines has not diminished in the same propor- tion : abundance of ore having made up for its poverty. Hence, if the mountain of Potosi is not, as formerly, the richest deposite of ore in the world, it may, however, be still placed immediately after the famous vein of Guanaxuato. The ore lies in veins in a primitive clay state, which composes the principal mass of the mountain, and is cov- ered by a bed of clay porphyry. This rock crowns the summit, giving it the form of a basaltic hill. The veins are very numerous ; several, near their outcrop, were almost wholly composed of sulphuret of silver, antimoniated sulphuret of silver, and native silver. Others, which offered near the surface merely sulphuret of tin, became richer as they descended. In 1790, seven copper mines were known in the viceroyalty of Buenos Ayres, seven of lead, and two of tin ; the last being merely washings of sands feund near the river Oraro. On the opposite flank of the chain, in a low, desert plain, entirely destitute of water, •which adjoins the harbor of Iquiqua, and forms a part of Peru, occur the silver mines of Huantajaya, celebrated for the immense masses of native silver which have been sometimes found in them. In 1758, one was discovered weighing eight cwts. M. Humboldt quotes 40 cantons of Peru as being at the present day most famous for their subterranean explorations of silver and gold. Those of gold are found in the provinces of Huaailas and Pataz ; the silver is chiefly furnished by the districts of Huantajaya, Pasca, and Chota, which far surpass the others in the abundance of their ores. The silver mines of the district of Pasco are situated about 30 or 40 leagues north of Lima, in 10^ degrees of south latitude, 4,400 yards above the sea-level, on the eastern slope of the Cordilleras, and near the sources of the river Amazon. They were dis- covered in 1630. These mines, and especially those of Cero of Yauricocha, are actually the richest in all Peru. The ore is an earthy mass of a red color, containing much iron, minded with particles of native silver, horn silver, &,c., constituting what they call Pacos. At first, nothing but these pet co« was collected ; and much gray copper and antimoniated sulphuret of silver were thrown among the rubbish. The mean product of all the ores is i_ _ ; or an ounce and _2j_ per cwt. ; although some occur which yield 30 or 40 per cent.** These rich deposites do not seem to be extended to a great depth ; they have not been pursued further than 130 yards, and in the greater part of the workings only to from 35 to 45. Forty years ago, these mines, which produced nearly 2,000,000 of pias- tres annually, were the worst worked in all South America. The soil seemed as if riddled with an immense number of pits, placed without any order. The drainage of the waters was effected by the manual labor of men, and was extremely expensive. In 1816, some Europeans, among whom were several miners from Cornwall, mounted sev- eral hish-pressure steam-engines, imported from England, which introduced a consid- erable improvement in the workings. The mines of the province of Chota are situated in about seven degrees of south lati- tude. The principal ones are those of Gualcayoc, near Mecuicampa, discovered in 1771 ; their outcrop occurs at the height of 4,500 yards above the sea; the city of Mecuicampa itself has 4,000 yards of elevation, that is, higher than the highest summits of the P>Te- nees. The climate is hence very cold and uncomfortable. The ore is a mixture of sul- phuret of silver and antimoniated sulphuret, with native silver. It constitutes veins, of which the upper portion is formed of pacos, and they sometimes traverse a limestone and sometimes a hornstone, which occurs in subordinate beds. The annual produce of the mines is 67,000 marcs of silver, according to Humboldt. In the districts of Huaailas and Pataz, which are at a little distance from the former two, gold mines are worked. This metal is extracted chiefly from the veins of quartz, which run across the primitive schistose mountains. The district of Huaailas contains, besides, lead mines. Peru possesses, moreover, some mines of copper. The quicksilver mines of Huancavelica, the only important mine of this species which has been worked in the New World, occurs on the eastern flank of the Andes of Peru, in 13 degrees of south latitude, at upward of 6,000 yards above the level of the sea. It does not seem refeirible to the same class of deposites with the mines hitherto mentioned. Indications of mercurial acposites have been observed in several other points of the Andei of Northern Peru, and of the south of New Granada. Lastly, mines of sal-gem are known to exist in Peru, especially near the silver mines of Huantajaya. On receding from the district of Chota, the Cordilleras are very indifferently stored with metallic wealth, to the isthmus of Panama, and even far beyond it. The kingdom of New Granada offers but a very small number of silver mines. There are some aurif- erous veins in the province of Antioquia, and in the mountains of Guamoco. The prov- ince of Caracas, the mountains of which may be considered as a ramification of the Cordilleras, presents at Aroa a copper mine which furnishes annually from 700 to 800 metric quintals (1,400 to 1,600 cwt ) of this metal. Finally, we may state in passing, that there is a very abundant salt mine at Zipaquira, in the province of Sante Fe, and that between this point and the province of Santa-Fe-de-Bogota, a stratum of coal occurs at the extraordinary height of 2,700 yards. Although Mexico presents a great variety of localities of ores, almost the only ones worked are those of silver. Nearly the whole of these mines are situated on the back or the flanks of the Cordilleras, especially to the west of the chain, nearly at the height of the great table land which traverses this region of the globe, or a little below its level in the chains which divide it. They lie in general between 2,000 and 3,000 yards above the sea ; a very considerable elevation, which is favorable to their prosperity, because in this latitude there exists at that height a mean temperature, mild, salubrious, and most propitious to agriculture. There were at the time of Humboldt's visit, from 4,000 to 5,000 deposites of ore exploited. The workings constituted 3,000 distinct mines, which were distributed round 500 head quarters or Reales. These mines are not, how- ever, uniformly spread over the whole extent of the Cordilleras. They may be consid- ered as forming eight groups, which altogether do not include a greater space than 12,000 square leagues ; viz., hardly more than the tenth part of the surface of Mexico. These eight groups are, in proceeding from south to north, 1. The group of Oazuaca, situated in the province of this name at the southern extrem- ity of Mexico properly so called, toward the 17th degree of north latitude. Besides silver mines, it contains the only veins of gold explored in Mexico. These veins trav- erse gneiss and mica-slate. 2. The group of Tosco. The most part of the mines which compose it are situated 20 or 25 leagues to the south west of Mexico, toward the western slope of the great plateau. 3. The group of Biscania, about 20 leagues northeast of Mexico. It is of moderate extent, but it comprehends the rich workings of Pachuca, Real del Monte, and Moram. The district of Real del Monte contains only a single principal vein, named Veta Bezi- cana of Real del Monte, in which there are several workings ; it is, however, reckoned among the richest of Mexico. 4. The group of Zimapan. It is very near the preceding, about 40 leagues north- west of Mexico, toward the eastern slope of the plateau. Besides numerous sil ver mines, it includes abundant deposites of lead, and some mines of yellow sulphuret of arsenic. 5. The Central group, of which the principal point is Guanaxuato, a city of 70,000 in- habitants, placed at its southern extremity, and 60 leagues N. N. W. of Mexico. It comprises among others the famous mine districts of Gnanaxuato, Catorce, ZacaiecaSf Sombrerete ; the richest in Mexico, and which alone furnish more than half of all the silver which this kingdom brings into circulation. The district of Guanaxuato presents only one main vein, called the Veta Madre. This vein is enclosed principally in clay-state, to whose beds it runs parallel, but occasionally it issues out of them to intersect more modern rocks. The vein is composed of quartz, carbonate of lime, fragments of clay slate, &c. ; and includes the sulphurets of iron, of lead, and of zinc in great quantities, some native silver, sulphuret of silver, and red silver ; its power (thickness of the vein) is from 43 to 48 yards. It is recognised and worked throughout a length of upward of 13,000 yards; and contains 19 exploitations, which produced annually well on to 1,200,000Z. in silver. One of the explorations, that of Valenciana, produces 320,000/. ; being equal to about one fifteenth of the total prod- uct of the 3,000 mines of Mexico. Since 1764, the period of its discovery, its neat annual product has never been less than from two to three millions of francs (80,000/. to :20,000/.) ; and its proprietors, at first men of little fortune, became, in ten years, the richest individuals in Mexico, and perhaps in the whole globe. The workings of this mine are very extensive, and penetrate to a depth of 550 yards. They employ a great many laborers. The district of Zacatecas presents in like manner only a single vein in greywacke ; which, however, is the seat oi several workings. The deposites mined at Catorce are in limestone ; the mine called Punssima dt Catorce has been explored to about 650 yards in depth ; and yielded, in 1796, nearly 20,00W There are also mines of antimony in the district of Catorce. 198 MINES. MINES. 199 II Toward the western part of the group of which we are now spealiing, copper minra are worked in the provinces of Valladolid and Guadalaxara ; the ores being chiefly com- posed of protoxide of copper (orange copper), sulphuret of copper, and native copper. These mines produce about 2,000 metric quintals of copper annually (440,000 lbs. Lng- lish). In the same district, ores of tin are collected in the alluvial soils, particularly near Mount Gigante. The concretionary oxide of tin, so rare m Europe, is here the most common variety. This metal occurs also in veins. . The central part of Mexico contains many indications of sulphuret of mercury (cin- nabar) ; but in 1804 it was worked onlv in two places, and to an inconsiderable extent. 6. The group of new Gallicia is situated in the province of this name, about 100 leagues N. W. from Mexico. It comprises the mines of Balanos, one of the richest districts. 7 The group of Durango and Sonora, in the intendancies of the same name. It is very extensive. The mines are situated in part on the table land, and in part on the western slope. Durango is 140 leagues N. N. W. of Mexico. ., , j 8 The grcmp of Chinuahua. It takes its name from the town of Chinuahua, situated JOo'leagues N. of Durango. It is exceedingly extensive, but of little value ; and ter- minates at 29^ 10' of north latitude. . , . . • .v • v ««^;«« Mexico possesses, besides, several mines which are not included in the eight preceding groups. Thus the new kingdom of Leon, and the province of New Saint-Ander, present abundant mines of lead. New Mexico contains copper mines, and many others. Lastly, rock salt is mined in several points of New Spain ; and coal seems to occur m New Mexico. , . * i i The richness of the different districts of the silver mines or reales is extremely unequal. Nineteen twentieths of these reales do not furnish altogether more than one twellth ot the total product. This inequality is owing to the excessive richness of some deposites. The ores of Mexico are principally veins ; beds and masses are rare. The yems traverse chieflv, and perhaps only, primitive and transition rocks, among which certain porpnynes are remarked as very rich in deposites of gold and silver. The silver ores are mostly sulphuret of silver, black antimoniated sulphuret of silver, muriate of silver (hornsilver), and gray copper. Many explorations are carried on in certain earthy ores, called coUorados, similar to the pacos of Peru. Lastly, there are ores of other metals, which are worked principally, and sometimes exclusively, for the silver which they contain; such are the argentiferous sulphuret of lead, argentiferous sulphuret of copper, and argentiferous sulphuret of iron. , n * a Ores of very great richness occur in Mexico; but the average is only trom 3 to 4 ounces per cwt., or from 18 to 25 in 10,000. There are some, indeed, whose estimate does not exceed 2l ounces. Almost all the argentiferous veins affoi^d a little gold ; the silver of Guanaxuato, for example, contains ^ . The enormous product of the Mexican mines is to be ascribed rather to the great facility of working them, and the abundance of ores, than to their intrinsic richness. • j r ti v i^*>- The art of mining was little advanced in this country at the period of Humboldt s journey; the workings presented a combination of small mines, each of which had only one aperture above, without any lateral communications between the ditlerentsha ts. The form of these explorations was too irregular to admit of their being called workings bv steps. The shafts and the galleries were much too wide. The interior transport of the ores is generally effected on the back of men ; rarely by mules. The machines for raising the ore and drawing off the water are in general ill combined ; and the horse gigs for settin'' them in motion ill constructed. The timbering of the shafts is very imperfectly executed ; the walled portions alone are weU done. There are some galleries of drainage, but thev are too few, and ill directed. Latterly, English capitalists and miners have formed companies for working the silver mines of Mexico ; which will probably produce in time a happy revolution. , , i. • » *i v -i The silver ores of Spanish America are treated partly by fusion, and partly by amal- iramation, but more frequently by the latter mode; hence the importation of mercury forms there an object of the highest importance, especially since the quicksilver mine of Huar^cavelica fell in, and ceased to be worked. This mine is the only one in bpanish America which belongs to the government. For the modern state of these mines, sec The following table shows, accordina; to M. de Humboldt, what was the annual prod- uct of the silver mines of South America, at the beginning of this century. It is bounded in a great measure, upon official documents : — Mexico Peru - Buenos-Ayres ChQi - Total - 2,196,140 marcs, or 537,512 kil., worth £4,778,000 573,958 140,478 1,250,000 463,098 110,764 984,600 25957 6,827 60,680 - 3,259,153 795,581 7,073,280 To complete our picture of the mineral wealth of Spanish America, it remains to speak of its principal gold mines ; ^ut these belong to a geological locality, alluvial sands and gravel, very different from that of our present objects. The most important of these gold sands are washed on the western slope of the Cordilleras ; viz., in New Grenada, from the province of Barbacoas, to the isthmus of Panama, to Chili, and even to the shores of the seas of California. There are likewise some on the eastern slope of the Cordilleras, in the high valley of the river Ajnazons. The washings of New Granada produce also some platina. The mines, properly so called, and the washings of South America, furnish, altogether, 42,575 marcs, or 10,418 kilogrammes (22,920 libs. Eng.) of gold, worth 1,435,720/. MINES OF HUNGARY. The metallic mines of this kingdom, including those of Transylvania, and the Bannat of Temeschwar, form four principal groups, which we shall denote by the group of the N.W., group of the N.E., group of the E., and group of the S.E. The group of the N.W. embraces the districts of Schemnitz, Kremnitz, Kcenigsberg, Neuhsohl, and the environs of Schmoelnitz, Bethler, Rosenau, &c. Schemnitz, a royal free city of mines, and the principal centre of the mines of Hun- gary, lies 25 leagues to the north of Buda, 560 yards above the sea, in the midst of a small group of mountains covered with forests. The most part of these mountains, the highest of which reaches an elevation of 1,130 yards above the ocean, are formed of barren trachytes (rough trap rocks) ; but at their foot below the trachytic formation, a formation is observed, consisting of green-stone porphyries, connected with syenites, passing into granite and gneiss, and including subordinate beds of mica-slate and lime- stone. It is in this formation that all the mines occur. It has been long known that the green-stone porphyries of Schemnitz have intimate relations with the metalliferous porphyries of South America. M. Beudant, on com- paring them with those brought by M. de Humboldt from Guanaxuato, Real del Monte, &c., has recognised an identity in the minutest details of color, structure, composition, respectiv^e situation of the different varieties, and even in the empirical character of effervescence with acids. The metalliferous rocks appear at Schemnitz only in a space of small extent, comprehended partly in a small basin, of which the city occupies the south border. They are traversed by veins which, for the most part, cut across the strati- fication, but which also are sometimes obviously parallel to it. These veins are in general very powerful ; their thickness amounting even to more than 40 yards, but their extent in length seems to be usually inconsiderable. They are numerous and parallel to each other. It appears that they have no side plates of vein-stones (sallebandes), but that the metalliferous mass reposes immediately on the cheeks or sections of the rock, which is usually more or less altered, and includes always much pyrites near the point of contact, and even to a distance of several feet. The substances which constitute the body of these veins, are drusy quartz, carious quartz, ferriferous carbonate of lime, and sulphate of barytes, with which occur sulphuret of silver mixed with native silver containing more or less gold, which is rarely in visible scales ; sulphuret of silver, argen- tiferous galena, blende, copper and iron pyrites, &c. The sulphuret of silver and the galena are the two most important ores. Sometimes these two substances are insulated, sometimes they are mixed in different manners so as td furnish ores of every degree of richness, from such as yield 60 per cent, of silver down to the poorest galena. The gold seldom occurs alone; it generally accompanies the silver in a very variable proportion, which most usually approaches to that of 1 to 30. The ores of Schemnitz are all treated by fusion ; the poor galenas at the smelting house of Schemnitz (bleyhutte), and the resulting lead is sent as working lead to the smelting-houses of Kremnitz, Neusohl, and Schernowitz, whither all the silver ores prepared in the different spots of the country are transported in order to be smelted. The mines of Schemnitz, opened 800 years ago, have been worked to a depth of more than 350 yards. The explorations are in general well conducted. Excellent galleries of efflux have been excavated ; the waters for impulsion are collected and applied with skill. It may be remarked, however, that these mines begin to decline from the state of prosperity in which they stood several years ago ; a circumstance to be ascribed probably to the same pains being no longer bestowed on the instruction of the officers appointed to superintend them. Maria Theresa established in 1760, at Schemnitz, a school of mines. This acquired at its origin, throughout Europe, a great celebrity, which it has not been able to maintain. Kremnitz lies about five leagues N.N.W. of Schemnitz, in a valley flanked on the right by a range of hills formed of rocks quite analogous to the metalliferous rocks of Schemnitz. In the midst of these rocks, veins are worked nearly similar to those of Schemnitz ; but the quartz which forms their principal mass is more abundant, and con- tains more native gold. Here also are found sulphuret and hydrosulphuret oi antimony^ 200 MINES. MINES. t ' vhich do not occar at Schemnitz. The metalliferous district is of very moderate extent, and is surrounded by the trachytic district which overlies it, forming to the cast and west considerable mountains. The city of Kremnitz is one of the most ancient free royal cities of mines in Hun- gary. It is said that mines were worked there even in the times of the Romans ; but it is the Germans who, since the middle ages, have given a great development to these exploitations. There exists at Kremnitz a mint-office, to which all the gold and silver of the mines of Hungary are carried in order to be parted, and where all the chemical processes, such as the fabrication of acids, &c., are carried on in the large way. About six leagues N.N.E. from Schemnitz, on the banks of the Gran, lies the little village o( Neusohl, founded by a colony of Saxon miners. The mountains surrounding it include mines very different from those of which we have been treating. At Herren- grand, two leagues from Neusohl, grey wacke forms pretty lofty mountains ; this rock is covered by transition limestone, and is supported by mica-slate. The lower beds con- tarn bands of copper ores, chiefly copper pyrites. The mica-slate includes likewise masses of ore, apparently constituting veins in it. These ores have been worked since the 13th century. The copper extracted contains in a hundred weight six ounces ol silver. Eighteen or twenty leagues to the east of Neusohl, we meet with a country very rich in iron and copper mines, situated chiefly in the neighborhood of Bethler, Schmoelnitz, Einsiedael, Rosenau, &,c. Talcose and clay slates form the principal body of the moun- tains here, along with horneblende rocks. The ores occur most usually in strata. Those of iron, or sparry ore, and especially hydrate of iron, compact and in concretions, ac- companied with specular iron ore. They give employment to a great many large smelting-houses. The county of Goemar alone contains 22 works; and that of Zips also a great number. The copper mines lie chiefly in the neighborhood of Schmoelnitz and Gcelnitz. The copper extracted contains about six or seven ounces of silver in the hundred weight. Near Zalathna there is a quicksilver mine nearly inactive; and near Rosenau one of antimony. To conclude our enumeration of the mineral wealth of this country, it remains merely to state that there are opal mines in the environs of Czervenitza, placed in the trachytic conglomerate. GROUP OF THE NORTHEAST, OR OF NAGABANYA. The mines of this group lie in a somewhat considerable chain of mountains, which, proceedmg from the frontiers of Buchowina, where it is united to the Carpathians, finally disappears amid the saliferous sandstones between the TAem, iapoj, and Nagy Szamos, on the northern frontiers of Transylvania. These mountains are partly composed of rocks analogous to those of Schemnitz, traversed by veins which have much resemblance to the veins of this celebrated spot. Into these veins a great many mines have been opened, the most important of which are those of Nagabanya, Kapnick, Felsobanya, Miszbanya, Laposbanya, Olaposbanya, Ohlalapos. All these mines produce eold. Those ofLaposbanya furnish, likewise, argentiferous galena; those of Olaposbanya contain copper and iron ; and those of Kapnick copper. Realgar occurs in the mines of Felso- banya ; and orpiment in those of Ohlalapos. Several of them produce manganese and sulphuret of antimony. Lastly, toward the north, in the county of Marmarosh, lies the important iron mine of Borscha, and on the frontiers of Buchowina the lead mine of Radna, in which also much zinc ore occurs. The mines composing the group of the East, or of Jbrudbanya, occur almost all in the mountains which rise in the western part of Transylvania, between Zapo* and Maros, in the environs of Mrudbanya. M. Beudant notices in this region, limestones, sandstones, trachytes, basalts, and sienite porphyries, apparently quite analogous to the greenstone porphyries of Schemnitz. It seems to be principally in the latter rocks that the mines forming the wealth of this country occur ; but some of them exist also in the mica- slate, the greywacke, and even in the limestone. The principal mines are at Nagyao Koiosbanya, Vorospatak, Boitza, Csertesch, Fatzbay, Almas, Porkura, Butschum, and Stonischa. There are, in all, 40 exploitations; the whole of which produce auriferous ores smelted at the foundry of Zalathna. These mines contain also copper, antimonv and manganese. They are celebrated for their tellurium ore, which was peculiar to them prior to the discovery of this metal a few years back in Norway. The auriferous de- posites contained in the greenstone porphyry are often very irregular. The mines of Nagyag are the richest and best worked. The numerous veins occur partly in the sienite porphyry, and partly in the greywacke. The auriferous ore is accompanied with galena, realgar, manganese, iron, and zinc. There are iron mines in great beds near Vayda-Huniad and Gyalar. Some Cobalt mines are also noticed. The group of the S. E., or of the Bannat of Temeschwar, occurs in the mountains which block up the valley of the Danube at Orschova, through a narrow gorge of which the river escapes. The principal mines are at Oravitza, Moldawa, Szaska, and Dognaaczka 201 They produce chiefly argentiferous copper, yielding a marc of sUver (nearly \ pounds in the hundred weight, with occasionally a little gold. Ores of lead, zinc, and iron, are also met with. The mines are famous for their beautiful specimens of blue car' bonate of copper, and various other minerals. The mine of Moldawa aiibrds likewise orpiment. These metallic deposites lie in beds and veins ; the former occurring' par- ticularly between the mica-slate and the limestone, or sometimes between the limestone and the sienite porphyry. Well-defined veins also are known to exist in the sienite and the mica-slate. The Bannat possesses moreover important iron-mines at Dom- trawa and Ruchersberg; near Dombrawa sulphuret of mercury is found. Cobalt minrs occur likewise in these regions. 1 he mines constituting the four groups now described are not the sole metallic mines possessed by Hungary. A few others, but generally of little importance, are scattered over diflerent parts of this kmgdom. Several have been noticed in the portion of the Carpathians which separates Transylvania from Moldavia and Wallachia Their principal object is the exploration of some singular deposites of galena Besides the mines just noticed, Hungary contains some coal mines, numerous mines of rock salt, and several deposites of golden sands situafed chiefly on the banks of thi. Danube, the Marosch, and the Nera. The mines of the kingdom of Hungary produce annually, according to M. Heron de L'^i^n''^' ^*^^^ J'i'S '''' ^'V^ r^,''^' ^"»^^'^ ""^ §^°^^> '^^o^th 175,976/. ; and about 85,000 marcs, or 45,707 pounds of silver, worth 186,132/. The mines of Transylvania furnish nearly the half of the whole quantity of gold, and one seventeenth of the sUver now stated. The other mines of Europe produce together nearly twice as much silver but merely a few marcs of gold. Hungary aflfords besides from 18,000 to 20 000 metric quintals (about 4,000,000 libs. English) of copper annually, and a great deal s^I^^^. these mines proceed likewise from 3,000 to 4,000 metric quintals (660,000 to 880,000 hbs. Eng.) of lead ; a quantity not more than is neefled by the refining-houses for the ores of silver and gold. " MINES OF THE ALTAYAN MOUNTAINS. ^tr- ^^l ^^^nU" extremity of the chain of the Altayan mountains, which separate Siberia from Chinese Tartary, there exists a number of metalliferous veins, in which several important works have been established since the year 1742. They constitute the locality of the mines of Kolywan; the richest in the precious metals of the three districts of this kind existing m Siberia. These mines are opened up in the schistose formations which surround to the N. and W. and to the S. VV. the western declivity of the high granitic chain, from which they are separated by formations consisting of other primitive rocks. These schists alternate in some points with quartzose rocks, called by M. Renovantz hornstone, and with lime- stone. They are covered by a limestone, replete with ammonites. The metalliferous region forms a semicircle, of which the first lofty mountains occupy the centre The most important exploration of this country is the silver mine of Zmeof or Zmeinogarsk, m German Schlan?enberg, situated to the N.W. of the hi'^h mountainq m 5IO 9; 25' N. L. and 79° 49' 50" long, east of Paris. It is opened on a gr^t vein, which contains argentiferous native gold, auriferous native silver, sulphuret of silver, hornsilver, gray copper, sulphuret of copper, green and blue carbonated copper, red oxide of copper, copper pyrites, sulphuret of lead, and great masses of testaceous arsenic slightly argentiferous. There occur likewise sulphuret of zinc, iron mrit^ , and sometimes arsenical pyrites. The gangues (vein-stones) of these different o^ls are sulphate of baryta, carbonate of lime, quartz, but rarely fluate of Ih^e The pr^cinal vein, which IS of great power, has been traced through a lengtliT several hTndred fathoms, and to a depth of no less than 96 fathoms. In its superior portion it has an nclmation of about 50 degrees; but lower down it becomes nearTvmSl Its roof IS always formed of clay-slate. On the floor of the vein, the slate altlmates with horn stone. This vein pushes out branches in several directions; it is fn rrsected by ^^^ mrt'prot?tTv:"'Vh"'^r:f" ^'^"^^ ^' '"f^^^l^ "^'"^^^- '^^^ firs^Tears we' e""« mosi proauctive. The German miners employed subsequently by the Russian ^ '^^ ^^.^^ ^„d one of iS^Xof B^det aid in the ^^^^^o^o^^^^^^^^ ^^^ ^,^^,^^^, 3,, ,_ of Several important iron mines are explored in the Vos es , i ^^^ ^^^^^ FrLarU, in ihe department of the Vosges, whose or^s are r^^^^^^^^ ^^^^ ^^^ ^^^ hematite which appear to form J^^^^^^f^f fl: '^st^^^^ greywacke. The sub- irresular in a district composed of f^en tone limestone, an gy i^, i^,. There terranea A workings, opened on these dep«3»tes have been h^^ ^ y^ ^^^^^ ^^ ^ has been discovered lately in these mmes, an extremely ricn .^^^ ^^^ ^^^j^^ . At Rothau, a little to the east of Framont thin vems of red o.^^ ^^ .^^^ ^hese veins sometimes magnetic, owing Probably to an ad mixture 01 P ^^^^ ^^^^^^^ ^^^^^ ^^ run through a granite, that passes into sienite. At oa iron mines, analogous to those of Framont ^^^^^^ ^^^^^ Moselle, veins In the neighborhood of Ihann and ^f !.^J!,^^^"^^V,reywacke, clay-slate, and por- are worked of an iron ore, that traverse formations 0^^ g^^^„^„^ phyry. Lastly, in the north of the V^ f ^^^^^^f^f;-^^^^ several mines have been opened on very poj^ermi veu ^^^^^^ j^ bos ore, accompanied with a little <^^l;ri:rre2ced^Ly vad ores of lead, the most some points of these veins, the ^^.^'J «^^^^f JXed at Veite^ ^ndKalzenihal. These abundant being the phosphate, which «^J^f f ?'^^ j^jlo^ ^hose geological position is not veins traverse the sandstone of the ^os^es a formation who^^^^^^^ ^^^ preceding at alto-ether well known, but which contains »^«" ,""3"^f. ^""^'i^.i^atg. Many analogies Langenthal, at the foot of Mount Tonnerre -d - ,, palat na e. ^ M ^^.^^^^^ seem to approximate to the sandstone of the Vos es the sa ^^ Creutzwald, and rietitiro?^^:-^^^^^^^^^^ °^ ^''^'-'^ --- ^'^- Chapelle. At Cruilnich and Tholey, to the north of the Sairebruck, mines of manganese are worked, famous for the good quality of their products. The deposite exploited at Crutt- nich seems to be enclosed in the sandstone of the Vosges, and to constitute a vein in it, analogous to the iron veins mentioned above. There has been recently opened a manganese mine at Lavelline, near La Croix-aux- mines, in a district of gneiss with porphyry. In the Vosges and the Black Forest there are several deposites of anthracite (stone- coal), of which two are actually worked, the one at Zunswir, near Oflenbourg, in the territory of Baden, and the other at Uvoltz, near Cernay, in the department of the Upper Rhine. There are also several deposites of tlie true coal formation on the flanks of the Vosges. MINES OF THE HARTZ. The name Hartz is given generally to the country of forests, which extends a great many miles round the Brocken, a mountain situated about 55 miles W.S.W. of Magde- bourg, and which rises above all the mountains of North Germany, being at its summit 1226 yards above the level of the sea. The Hartz is about 43 miles in length from S.S.E. to N.N.W., 18 miles in breadth, and contains about 450 square miles of'surface. It is generally hilly, and covered two thirds over with forests of oaks, beeches, and firs! This rugged and picturesque district corresponds to a portion of the Silva Hercynia of Tacitus. As agriculture furnishes few resources there, the exploration of mines is almost the only means of subsistence to its inhabitants, who amount to about 50,000. The principal cities. Andreashcrg, Clausthal, Zellerfeld, Mtenau, Lauienthal, IVildemann] Grundy and Goslar, bear the title of mine-cities, and enjoy peculiar privileges ; the people deriving their subsistence from working in the mines of lead, silver, and copper, over which their houses are built. The most common rock in the Hartz is greywacke. It encloses the principal veins, and is covered by a transition limestone. The granite of which the Brocken is formed supports all this system of rocks, forming, as it were, their nucleus. Trap and hornstone rocks appear in certain points. The veins of lead, silver, and copper, which constitute the principal wealth of the Hartz, do not pervade its whole extent. They occur chiefly near the towns of Andreas- berg, Clausthal, Zellerfeld, and Lautenthal ; are generally directed from N.W. to S.E. and dip to the S.W., at an angle of 80'^, with the horizon. ' The richest silver mines are those of the environs of Andreasberg, among which may be distinguished the Samson and Newfang mines, worked to a depth of 560 yards. In the first of them there is the greatest step exploitation to be met with in any mine. It is composed of 80 direct steps, and is more than 650 yards long. These mines were discovered in 1520, and the city was built in 1521. They produce argentiferous galena, with silver ores properly so called, such as red silver ore, and ore of cobalt. The district which yields most argentiferous lead is that of Clausthal ; it comprehends a great many mines, several of which are worked to a depth of 550 yards. Such of the mines as are at the present day most productive, have been explored since the first years of the eighteenth century. The two most remarkable ones are the mines of Dorothy, and the mine of Caroline, which alone furnish a large proportion of the whole net prod- uct. The grant of the Dorothy mine extends over a length of 257 yards, in the direc- tion of the vein, and through a breadth of nearly 22 yards perpendicularly to that direc- tion. Out of these bounds, apparently so small, but which however surpass those of the greater part of the concessions in the Hartz, there was extracted from 1709 to 1807 in- clusively, 883,722 marcs of silver, 768,845 quintals of lead, and 2,385 quintals of copper. This mine and that of Caroline have brought to their shareholders in the same period ol time, more than 1,120,000/.; and have besides powerfully contributed by loans with- out interest to carry on the exploration of the less productive mines. It was in order *r ^-r^u ^r^ drainage of the mines of the district of Clausthal, and those of the district 1^^ adjoining, that the great gallery of efflux was excavated. Next to the two districts of Clausthal and Zellerfeld, and Andreasberg, comes that of ixoslar, the most important working in which is the copper mine of Rammelsberg, opened since the year 968, on a mass of copper pyrites, disseminated through quartz, and min- gled with galena and blende. It is worked by shafts and galleries, with the employment 01 hre to break down the ore. This mine produces annually from 1,200 to 1,300 metric quintals (about 275,000 libs, avoird.) of copper. The galena extracted from it yields a small quantity of silver, and a very little gold. The latter metal amounts to only the nve-millionth part of the mass explored ; and yet means are found to separate it with advantage. The mine of Lauterberg is worked solely for the copper, and it furnishes annually near 66,000 libs, avoird. of that metal. Besides the explorations just noticed, there are a great many mines of iron in differ- ent parts of the Hartz, which give activity to important forges, including 21 smelting 206 MINES. MINES. 207 h 1«« The principal o-es are sparry iron, and red and brown hematites, which occni produce annually 33,000 libs, avoird. of lead. manganese. ^ At the southern foot of the Hartz, at Ileleld, ^/'L^^^^^^^^^ Iqq years. The The exploration of the Hartz "^^"^^^"^'^y ,^,^/T.^h,er^^^^^^^^^ Theirgross epoch of their greatest prosperity was the ^^f^^ °^^^^^^^^^^^ is^heir principal annual amount was in 1808 upward «[^«.^^..^^J^^^^^^^^ with 36,000 marcs, or product, of which they ff"^^\^T?fiO%offiavo^d. of copper, and a very great ^^::^Sr'^e;^^ of the S^ming operations . and ^^^s^?^ris^?rj^^^^f?^f^ and economized for floating down the timber ^"VpTrconstructerremark^ for their view, dams or lakes, canals, and aqueducts, ^^^^ ^e^ ^^on^^^^^^^^^^^ ^n)und the moun- good execution. The water-courses are [f ""^«i "^^^f^erie^ The open channels col- fain-sides, or throngh their interior as s^^tejr^^JJ^^^^^^^^^ ^^^^ .^e lect the rain-waters, as well as ^^ose proceeding from the^m^^ subten^inean con- springs and streamlets, or small "Y^'^^J^J^/^'^Vc^din- whose circuits they cut short, duits are in general the continuation of the precedmw^^^^^^ The banks of some These water-courses present ^development in whole otliomiie^ ^^ ^^^^^^^^^^ Ih^e 7er.l\Xl'MTo'Lier, and 37 for the extraction of ores. MINES OF THE EAST OF GERMANY. parts of Saxony, Bavaria, Austria, Moravia and Silesia. ^^^^^ries, the richest nnlcotalt. 'Thfse mines, whose exploration ^^^f.^^^ S:d7m^f^^^^^^^^^^^ b'een ticularly those situated on the 'IO^^.^^'-YJ PliXd at Fr^^^^^^^^ at one time consid- lon^ celebrated. The school of mines ^ff^\'^|^"J^.fJ^'J\he^^st important workings, ered as the first in the world. This '« a ^mall city near t^ie mo i i P ^^^ _ 8 leagues W.S.W. of Dresden, oward the ^^^^f^^/-^^^^^^^^ district, well birge^ 440 yards above the level of the ^^^^'J^ °,°, ,Xrth " woS^^ the mines, and cleared of wood. These circumstances have modified the^y^^^^^^^^ ^^.^^ render it difficult to draw an exa^t Pard^^^^ a^l p ^Sl arlT remarkable for the perfection are their rivals in good exploration ; they are pecm^^^^ with which the engines are ^xecued both for drainage and exl^^^^ » ^^^ ^^^ by water or horses ; for the regularity «{^^\'J«^;^ ^^^ ^^^^Tonn^ belonging the beauty of their walling masonry. I" ^^^^^.P^^y^^^^^^^^ qqq ^^ jq noo men, who .hough auite differe^ m h« -^f J-J,\Xet;^ exeeeding a few feet. For a long time back, those of «h?J"V™"^ ™ /^J^, "^^^ the increas- ii7^e-^h':^iL-=f ?. HeSj^SS • a^ t^ tr^i:5«^e ^^^::^^^:'^^r:^i^^^^^^^^^^^^ -« of Besche.- gluck is also very rich. , j ^^ ^g formerly so flour- Among the explorations at Erzgebrge,theT^e are none Tvhicn^ Freyberg. In iSe\rce°ir^e.rfrc^e«?^^^^ "tirtCtL^l<^t uKscribe in detail the sUver mine, that occur Be„ Ehren/riedersdorfy Johanna-Georgenstadt, jlnnaberg, OberwieteniheUf and Schnetberg. Those of the last three localities produce also cobalt. The mines of Saint-Georges, near Schneeberg, opened in the fifteenth century as iron mines, became celebrated some time after as mines of silver. Toward the end of the fifteenth century, a mass of ore was found there which afforded 400 quintals of silver ; on that lump, Duke Albert kept table at the bottom of the mine. Their richness in silver has diminished since then ; but they have increased more in importance during the last two hundred years, as mines of cobalt, than they had ever been as silver mines. Saxony is the country where cobalt is mined and extracted in the most extensive manner. It is obtained from the same veins with the silver. Smalt, or cobalt-blue, is the principal substance manufactured from it. The lead and the copper are in this country only ac- cessory products of the silver mines, from which 120,000 lbs. avoird. of the first of these metals are extracted, which are hardly sufficient for the metallurgic operations ; and from 50,000 to 60,000 lbs. of copper. A little bismuth is extracted from the mines of Schneeberg and Freyberg. Some manganese is found in the silver mines of the Erzge- birge, and particularly at Johanna-Georgenstadt. The mines of Saxony produce a little argentiferous galena, and argentiferous gray copper ; the minerals with a base of native silver are the principal ores ; they are treated in a great measure by amalgamation. All those of Freyberg are carried to the excel- lent smelting-house of Halsbriick, situated on the Malde, near that city. The average richness of the silver ores throughout Saxony is only from 3 to 4 oz. per quintal : viz., nearly equal to that of the ores of Mexico, and very superior to the actual richness of the ores of Potosi. The silver extracted irom them contains a little gold. The Saxon mines produce annually 52,000 marcs of silver. Of these, the district of Freybers alone furnishes 46,000 ; and among the numerous mines of that district, that of Himmelsfurst of itself produces 10,000 marcs. Silver mines exist also on the southern declivity of the Erzgebirge, which belongs to Bohemia, at Joachimsthal and Bleystadt, to the northeast of Eger. Argentiferous gjTlena is chiefly extracted from these. The mines of Joachimsthal have been explored to a depth of 650 yards. They were formerly very flourishing ; but in 1805 they were threat- ened with an impending abandonment. The ancient mines of Kuttenber?, situated in the same region, have been excavated, according to Agricola,to upward of 1,000 yards from the surface soil. The southern slope of the Erzgebirge possesses cobalt mines like the northern slope; but they are of much less importance. Some occur, particularly in the neighborhood of Joachimsthal. Lastly, on the same slope, slightlj^-productive copper mines are men- tioned at Groslitz, near Joachimsthal; at Catharineberg, 8 leagues north of Saatz ; and at Kupferberg, lying between the two. At Groslitz, the ore is a cupreous pyrites, ac- companied by blende. The ores of Catharineberg are argentiferous. Next to the silver mines, the most important explorations of the Erzgebirge are those of tin. This metal occurs in veins, massive, and disseminated in masses of hyalin gray quartz, imbedded in the granite ; it is also found in alluvial sands. The most important tin mine of the Erzgebirge is that of Altenberg, in Saxony, which has been under working since the fifteenth century. Some tin is mined also near Gayer, Ehrenfriedersdorf, Jo- hanna-Georgenstadt, Scheibenberg, Annaberg, Seifl'en, and Marienberg, in Saxony. At Zinnwald it is also found; where the stanniferous district belongs partly to Saxony and partly to Bohemia ; as also important mines occur in the latter territory at Schlacken- wald and Abertham, and slightly-productive ones at Flatten and Joachimsthal. In sev- eral of these mines, particularly at Altenberg and Gayer, fire is employed for attacking the ore, because it is extremely hard. In almost the whole of them, chambers of too grea't dimensions have been excavated, whence have arisen, at diflferent epochs, vexa- tious sinkings of the ground. One of these may still be seen at Altenberg, whihh is 130 yards deep, and nearly 50 in breadth. The mines of Abertham are explored to a depth of d50 yards, and those of Altenberg to 330. The tin mines of the Erzffebirffe produce annually 484,000 lbs. avoird. of this metal. * s p ucc The tin ores are accompanied by arsenical pyrites, which, in the roastin<' that it un- dergoes, produces a certain quantity of arsenious acid. The Erzgebirge presents also a great many iron mines, particularly in Saxony, at Rodenberg near Cradorf, in the county of Henneberg, where the workings penetrate to a depth of 220 yards, and m Bohemia, at Flatten, where may be remarked especially the great explorations opened on the vein of the Irrgang. There is also in the Erzgebirge a mine of anthracite (stone coal) at SchcBnfcld, near rrauenstein, m Saxony. The ancier^t rock-formations which appear in the remainder of Bohemia, and in the adjacent portions of Bavaria, Austria, Moravia, and Silesia, are much less rich in metala TM, P?^^^^^"""^* ^^ explorations of much importance exist there. The Ftchtelgebirge, a group of mountains standing at the western extremity of the im 208 MINES. MINES. 209 ;, r ill ;i 1^' Erz.'ebirge, between Hoff and Bayreuth, contains some mines, among which may be notlJed nrinciDally, mines of magnetic black oxide of iron. -or K-ar r.r ArfentSus likd mines have been mentioned at Af««, 25 leagnes W.S.W. of Pr^f e at the N.Etbase of the western part of BomerwaWgeiirge a cham of mouma « wSepaa'e Bohemia from Bavaria. There are soo»e also at ■P'-^^f^Xm Mollau s w nf Pr;i.ne at the extremity of the mountains which separate Behrun Jrom Moiaau. lA^lie latter^ the arlenS^ is accompanied by blende, in wh.ch the presence '?ealrurhiwn ^toerved. Ihese mines, and those of Joach^sth^^ furnish annually at presen^^^^^^^^^^^^ mintTfmeTcuryThe^asferrprt of the Bomerwaldgebirge, which separat^^ mir/romAustrSand Moravia, presents some mines on >t'?»"'^«'f .f P/„4„^,^17J^ quantity of copper, and from 600 to ™ """^^'q'^'^^/ ' ,„d ^e mines of arsenical ^^S^^^^I.Xtf^^^'i^^^ot chrysoprase exists in the mountain of Kosennitz. MINES or THE CENTRE OF FBANCE. res'arettrrTetS: e," frhi:i:Vv'er;''?ew'^Lff ^^^^ Tur towarf the eastl™ border of the mass of primitive formations, m a zone charac- '-rvllfeLran'dt-vfaZ^^^^^^^^^^^ r^^ ):Lr.ZrS/e,Te"^«eTof 'tt S fnd'Vt A department of the Ir There exisraV&ilBel e, 2 lea^^ to the south of Chessy, a deposite of copper *" •; Tb/?w nf Chessv which was at one time worked, but is now standing st 11. pyrites like that of Ches^y^ Yment rfSaone et Loire, a very abundant deposite of oxide ^f' Xa-trj o^s'e^trapTarenUy forming a mass in the granite, or perhaps above "•l.-^Sl ZnZ "„rEruS"-ear Couches, in the same department, an ore of '^^^^::^X:^^^^^. « <•««« vemof smphure. of antimony " There'are also in the centre of France some explorations of galena, «»t;"'0»T. «»d TSeT^rrt\XTre'°w^3 "dfr^'ii^iTar^^^^ At presemrresearches are making with a view of discovering deposttes of such magnv- tude as to pay the expense of working it. MINES OF THE NORTH OF PORTUGAL AND THE ADJOINING PARTS OK SPAIN. Ti,. r.rthaffinians anoear to have worked tin mines in this part of the peninsula. It is saS that sSrerlySed in Portugal in the environs of Viscu, a province of Beix., at a place called Burraco dt Stanno, Some veins of the same metal were discovered in 1787, near Monte-Rey, in the south of Gallicia. They were lully two yards thick, and were incased in granite. This province presents also deposites of anlphuret of antimony. Some analogous ores are found in Castille and Estremadura. Lead ores were worked in the last century not far from Mogadouro, on the banks of the Sabor, in the province of Tras-Ios-Montes, and near Lon^roiva on the banks of the Rio-Prisco. Mines of plum- bago occur near Mogadouro. There are also some iron mines in the same country near Felguiera and Torredemnacorvo. They supply the iron-works of Chapa-cunha. Two very ancient establishments of the same kind exist in the Estremadura of Portu«'al; the one in the district of Thomar, and the other in that of Figuiero dos Vinhoss : fhev are supplied by mines of red oxide of iron, situated on the frontiers of this province and of Beira. One deposite of quicksilver ore occurs at Couna in Portugal. At Rio Tinto in Spain, on the fix)ntiers of Portugal, there is a copper mine which produces about 33,000 libs, avoird. of this metal per annum. The ore is a copper pvrites. The moun- tains in the environs of Oporto present everywhere indications of the ores of copper and other metals; and it appears that all this part of the peninsula is in general rich in me- tallic treasures, but that the want of wood prevents their being mined to advanta<'e. Besides, many of the deposites which originally existed there must be in a great meaa- ure exhausted. It was in these countries chiefly that the gold and silver mines lay, which the Carthaginians and Romans worked with so much advantage, and contested in so keen a manner. Near Loria (the ancient Numantium), Azagala, and Burgos considerable vestiges of the ancient workings may still be seen. * MINES OF BRITANNY, Britanny has hardly a better share in mineral wealth than the countries we have just passed in review. There exist in it at this moment only two important exploitations • which are, the lead mines of Poullaouen and Huelgoat, situated near Carhaix. The mine of Huelgoat, celebrated for the plomb-gomme (hydro-aluminate) discovered in it, ia opened on a vein of galena, which traverses transition rocks. The workings have sub- sisted for about three centuries, and have attained to a depth of 220 yards. The vein oC Poullaouen, called the New Mine, was discovered in 1741. It was powerful and very rich near the surface ; but it became subdivided and impoverished with its depth, notwith- standing which the workings have been sunk to upward of 180 yards below the sur- face. In these mines there are fine hydraulic machines for the drainage of the waters with wheels from 14 to 15 yards in diameter ; and water-pressure machines have been recently constructed. The mines employ more than 900 workmen, and furnish annually more than 1,200,000 lbs. avoird. of lead, several thousand pounds of copper, and 2,000 marcs, or 1,034 lbs. avoird. of silver. These are the most important metallic mines of France. Several veins of galena exist at Chaieldudren, near Saint-Briex, but they are not worked at present. There is also one at Pompean, near Rennes, which has been worked to a depth of 140 yards, but is in like manner now abandoned. It affords, besides the galena, a very large quantity of blende (sulphuret of zinc), of which attempts are making to take advantage. There occurs, also, a lead mine at Pierreville, department of the Channel, in a formation connected with the system of Britanny. It is opened on a vein which traverses a limestone pretty analogous to that of Derbyshire. The same depart- naent presents a deposite of sulphuret of mercury at Menildot. A few years ago, some tin ore was discovered at Pyriac, near Guerande, in the department of the Loire Inferi- eur, but the researches since made to find workable deposites have been unsuccessful. A mine of antimony was worked at La Ramee, department of La Vendee. Several of the coal deposites lately mined in the departments of La Sarthe, La Mayenne, and Mayenne- et-Loire, ought probably to be legarded as more ancient than the genuine coal measure*. Table of the production of the French mines, during the year 1832.* Species of Mine. Number of mines. Extent of surface conceded. Number of workmen. Production is in lOths of a ton. Value of the rough product in francs. Metallic Subttances. Antimony Copper Iron Manganese Gold Lead and silver Zinc 16 8 131 8 1 33 1 Kilom. Carres. 93,8954 274,18 1-051,391 16,54 0-49 614,23 6,80 130 258 8917 66 1259 Melted antim. 1-030,98 Black copper 1-376 Rough ore 15-814,690 6-087 8-505 71-232,75 247.680 3,630-806,81 ' 66-849,88 742-051 Voun. * lAnnaJts des Mines, torn, v., 1834, p. 67«> 14 aio •■ f i >. }, 1^^ 'J P. If 'I i i itt' MINES. MINES OF THE CORRESPONDING COASTS OF GREAT BRITAIN AND IREI»AND. MINES. 211 The mines comprehended in this section are situated, 1, in Cornwall and Devonshire ; 2 in the S.E. of Ireland ; 3, in the island of Anglesey and the adjoining part of Wales ; i, in Cumberland, Westmoreland, and the north of Lancashire, and the Isle of Man j 5' in the south of Scotland; 6, in the middle part of the same country. Cornwall and Devonshire present three principal mining districts ; viz., the portion of Cornwall situated in the environs and S.W. of Truro, the environs of St. Austle, and the environs of Tavistock. , j • . The first of these districts is the most important of the three m the number and richness of its mines of copper, tin, and lead. The ores of copper, which consist almost entirely of copper pyrites and common sulphuret of copper, constitute very regular veins running nearly from east to west, and incased most frequently in a clay-slate of a talcose or horn- blende nature, called fet7/a«, and sometimes in granite, which forms protuberances in the middle of the schists. The tin occurs principally in veins, which, like the preceding, traverse the killas and the granite. They are also very often directed nearly from east to west, but they have a difl'erent inclination, or dip, from that of the copper veins, which cut them across and interrupt them, and are consequently of more recent formation. The tin ore forms also masses, which appear most usually attached to the veins by one ol their points. Lastly, it is found in small veins which traverse the granite, principally near the points where this rock touches the killas. Certain veins present the copper and tin ores to£?ether ; a mixture which occurs chiefly near the points of intersection of the two metallic veins. Certain mines furnish at once both copper and tin ; but the most part produce in notable quantity onlv one of these metals. The most important copper mine«» are situated near Redruth and Camborn ; among which may be noted particu- larly those called Consolidated Mines, United Mines, Huel-Alfred, Dolcoath, Poldice, &c The principal tin mines are situated still farther to the southwest, near Helston, Saint-Yues, &c. Those called Hud Vor, Great Huas, are particularly noticed. There are several mines in Cornwall of which the crossing veins which at once intersect and throw out the veins of copper and tin, contain argentiferous galena and several ores of silver. There existed formerly mines of argentiferous lead near Helston and Truro. There may be now seen near Saint Michael an ore which, melted and cupelled on the spot yields from an ounce and a half to two ounces of silver per quintal. Near Cal- stock a silver mine is worked, called Huel-Saint-Vincent, which has aflorded, it is said, in some months, from 900 to 1,000 lbs. avoird. of that metal. The ore, consisting of hornsilver and native silver, is treated on the spot. « . . , -.ir , ry ■ • In the environs of Saint Austle, the copper mines of East Crtnnis and West Crtrmts deserve to be noticed, as well as me lin mine of Polgooth, opened on a tin vein ; and the mine of Carclaise, explored in the open air on a system of small veins of this metal. Near Tavistock there occur mines of copper, tin, and lead. Among the last may be remarked particularlv that called Hnel Betsey, of which the ores melted and cupelled on the spot, afford an ounce and a half of silver per cwt. ; and that of Beeralston, whose ore is sent to Bristol to be smelted there. It yields from four to five ounces of silver per cwt. •, ^ o 1 ^. • rt 11 There are mines of antimony at Huel-Boys in Devonshire, and at Saltash m Cornwall. The tin and copper ores of Cornwall are accompanied with arsenical pyrites, which is turned to some account by the fabrication of white arsenic (arsenious acid). Cornwall and Devonshire produce annually about 6,160,000 lbs. avoird. of tin; 18,700,000 lbs. avoird. of copper; and 1,760,000 lbs. avoird. of lead. See Copper and Tin The tin is treated at the mine localities : but the copper ores are sent in their natural state to Swansea in South Wales, to be smelted. Wood and labor being very dear in Cornwall and Devonshire, the mineral depositea of these counties can not be worked out so completely, nor can the mechanical prepara- tion of the ore be so far pushed, as in several other parts of the world. But all the op- erations which appear advantageous are conducted in the most judicious, most economical, and most expeditious manner. Steam-engines are erected there, some of them posses- sin" the power of several hundred horses. Many of the mines are explored to a depth of upward of 400 yards ; and several are celebrated for the boldness of their workings. The one called Botallock Mine, situated in the parish of St. Just, near the Cornwall cape is opened amid rocks which form the seacoast, and stretches several hundred yards under the sea, and upward of 200 yards beneath its level. In some points so small a thickness of rock has been left to support the weight of the waters, that the roll- ing of pebbles on the bottom is distinctly heard by miners during a storm. The mine of^Huel-werry, near Penzance, was worked by means of a single shaft opened on the toast, in a space left dry by the sea only for a few hours at every ebb. A small wooden tower was built over the mouth of the shaft, which, being carefully calked, kept out the waters of the ocean when the tide rose, and served to support the machines for raisin, the ore and drainage. A vessel driven by a storm overturned it during the ni«'ht a^ put a period to this hazardous mode ofmining, which has not been resumed ° ' The most considerable mines of Ireland are those of Cronebane and Tingrony, and of Ballymartagh, situated three leagues S.W. of Wicklow, in the county of thf s^e nle. Their object IS to work the copper pyrites, accompanied with some other ores of copper galena, su phuret of antunony, as well as pyrites of iron, which forms several flattened masses m the clay-slate. Pretty extensive workings have been made here ; and the ore was transported in its natural state to Swansea. Veins or masses of copper pyrites and galena are mined in some other points of the southeast of Ireland, but nonVof them with any notable advantage. The principal is the lead mine situated in the county of Tinnerarv near the village called Silver Mines, absurdly enough, because, though s'lVrwrou^^^^^^^ for in the lead, none was extracted. Many iron mines anciently existed in Ireland bui he destruction of the forests has considerably diminished their number and aS"^ that only a few remain m Kilkenny, Wicklow, and Queen^s County »^"viij, 50 The isle of Anglesey is celebrated for its copper mines, the principal of which are Mona-mme and Parys-mountain. The ore is a copper pyrites, sometimes of considerabk volume, lying in masses m a formation contaming serpentines and different talcose rock. For a long time the workings were carried on in the open air, but the exterior exnloral Uon has been thereby compromised. The neighboring coasts of Wales present some inmes of the same nature All the ores are treated in a smelting-house estaWbh^™^ the isle of Anglesey. The formation of slate-clay and greywacke! which consiitutP^^hA greater part of Wales, and some of the adjoining distrfcts'ofEn5and,1ncludetve^^^^^ lead mines, of which we shall presently speak in noticing those of far greater important contained m the more recent limestone formations of the same regions ^ Pretty important mines of copper pyrites and red hematitic .ron'are worked in Westmoreland, and m the neighboring parts of Cumberland and LancasMre The copper ores, and a portion ot the iron ones, are embarked for Swansea. The rest of the .T^f^M ^''^i•^'"'■'*'r '^' »n Wast furnaces supplied with wood charcoal The isle of Man aftords indicaUons of lead, copper, and iron, in the mountains of Snafle which constitute Its centre. At Borrowdale in Westmoreland, a mi^e Tgi^phUe (plumbago) has been worked for a long period. It furnishes the black lead^f the f^rtation'.'"' '' '" ''''''"''' '"'' '^' "°^'^- ^^^ 'nineral occurs in mass In a taUsJ There are famous lead mines in the south of Scotland, at Leadhills in Lanarkshir** . At'cX ?n' K rkc,r "nff ' ''^ ^^y^^'"^'.- Some m'anganese ha^ i"so been found At Cally, ,n Kirkcudbrightshire, a copper mine has been lately discovered ; and a mine of antimony has been known for some time at West Kirk in Dumfriesshire • but neiTher has been turned to good account. ""^r^snire , oui neiiner In the middle part of Scotland, the lead mines of Strontian in Argyleshire deserve to be noticed, opposite to the northeast angle of the isle of Mull. They are onened o« veins which traverse gneiss. According to Mr. John Taylor, these mines and those of Leadhills produce annually 5,610,000 lbs. avoird. of lead. wh^.?^?In*''^"r!'j°^^''*"^'^ ^""^'^ ^^"V" atGrantown on the banks of the Don, a river b^enUrL'arAtu^r^ '"^'^ ""' ^'"'"" ^ "''^^ °' "^^"^ ''''''''' ^^^^ A copper mine was discovered some years back in one of the Shetland isles- and chromate of iron is now extensively worked there in serpentine and talc: ' MINES OF THE NORTH OF EUROPE. These mines are situated for the most part in the south of Norway, toward the middle of Sweden, and in the south of Finland, a little way from the shortlit iTne dJaw^from the lake Onega to the southwest angle of Nor^vay. A few mines occur in thr^nrthp™ tZt^n.'lSir '''' '"^'^" ^'^ "^^''^ ''^'^^'^ ^' thesHe^Si^e: ZZ":, f«Ji'^ TTi°''^"^^****^°T*y ^'^»*''* ?? ^^^^'^^ «^t^« gulf of Christiania, and on the side feeing Jutland, principally at Arendal, at Krageroe, and the neighborhood The orS consist almost solely of black oxide of iron, which forms beds or veins of from 4 to 60 fee? I ' ''^r'"^ '"^ gneiss, which is accompanied with pyroxene (augite) epXtes garne^^^^^ co:;ts anTnaXZ'lv in?h'"''' ? %^r "-^ ^-^Iting firgS, sSedon t^eT^^^^^^ mmln r P"^'J"^*»^^y V^ the county of Laurwig. Their annual product is about 16i r^of^^LTon': S i^-efpr^'/" ''' '-- ^' -^ -"> ^- -«> «^eet iron,"nal^! eP^rlTJ^^'^''^''^ "k^.^^PP^"' °''°^'' '°"^ °^ ^hi<^h lie toward the south and the S. «nH L^'"''^'^' but the most considerable occur in the north, at Quikkne, zJel Selboe, and Rable. After the coal is extracted, a solid wall or " rib " of coal, from 6 to 10 yards thick, which is commonly termed a " fire-rib," is left all round the chamber, sepa- rating it from the next workings; and the entrance from the gate-road is securely walled up, to exclude the air, and prevent spontaneous combustion, which would otherwise, in a short period, take place. When an explosion occurs, it is generally followed by a second, or more, as proportions of the gas become successively charged with the due proportions of air ; and the liability to these terrible explosions will always remain in mines thus worked, till, by some efficient means, the gas can be allowed a continuous escape, and a current of air can be insured to move always in one direction, with sufficient power to overcome all extraneous disturbing forces, either of the wind or any atmospheric changes. In Jiff. 971, the system adopted and carried into operation by the author is shown. One pit a, is sunk, instead of two; and in the side of the shaft a smaller shaft 6 is cut, to form an "air chimney," and is afterwards separated from the main shaft; this air chimney is circular, and may be made about 3 feet diameter inside, or more, as may be required. The air-chimney is bricked at the same time with the shaft, — the circular brickwork of each forming a partition of double thickness and secure strength, from the two arches abutting against each other. 971 972 "^^^M^s^^ i The gate-road c, is driven from the shaft at the bottom of the coal, as in the ordinary plan ; but the air-head d is driven from the air chimney within 2 feet of the top of the coal, or higher if practicable, and runs into the vertical air chimney. The gate- road and air-head are carried forward in a parallel direction to the extent of the -vork, Vol. XL 16 If i' ((:! feit rii'i I '■[' 226 MINES, VENTILATION OF. as before described in the ordinary system ; and " spyonts ** 01 openings, e, are driven tipwards, to connect them at about every 15 yards — every spout being bricked up close, in succession, when a fresh one is made in advance, so as to make the current of air traverse tlie wliole extent of tlie gate-road before it rises up to the air-head and passe* aw.iv to the air chimney. These spouts can only be driven perpendicularly upwards from the gate-road to the air-head ; and each of them being about 18 feet long in the 30 feet coal, a formidable practical difficulty was experienced by the author in the King Swinford pits, where the coal being contiguous to a great vault, it abounded in gas to so grciit a degree that when a spout was carried up a very few feet, it became so filled wi h gas tliat no man could work in it. But this difficulty was overcome by boring upwards fr<.m the spout a hole, 4 inches in diameter, into the air-head; the gas then passed otf instantly, followed by a stream of air sufficient to ventilate the gate-road, ind to enable the men to work with candles in the spout with perfect safety. The excavation of the coal is commenced in the same manner as in the ordinaiT system, by driving at right angles from the end of the gate-road, to begin a "side of work ;" and ihe ventilation is carried on completely and continuously from the extremity of the working, whilst the whole of the coal to the top is removed. The whole of the gan is constantly drained off from the upper surface of the coal by the air-head, and the numerous spouts or cross drains, which remain all open to the air-hea 1, by means of a small pipe-hole left in the stopping as they are successively stopped, and which constantly drain otf the gas most effectually, by piercing through and cutting the horizontal layei-s of coal, and thus tapping the several strata at so many different points. By this system the danger of any accumulation of gas in the cavities of the upper part of the workings is effectually prevented. . , j In the ordinary system of ventilation, it is manifest that only a very slight determming power compels the air to travel constantly in the same direction. Its current is, at all times, weak and insufficient, and liable to be deranged by the action of the wind, or at- mospheric changes ; and it is under no command whatever. To ensure safety, a constant current of air is indispensably necessary; it should be a current, too, maintained by natural causes, as far as possible, and never interrupted, for the reasons already assigned ; and sliould be one that would not vary or fail. To effect this, the ascending column of air must be rendered specifically lighter than the air of the dericending column, which circulates through the workings; and this difference of specific gravity must be maintained constantly free from disturbance, by accidental causes, and, to such an extent, as to produce, undei- all circumstances, a total amount ol' propelling power that is found sufficient for the complete ventilation of the mine. This is accomplished by conducting the whole ofthe gas m a continuous ascend- ing column, free from interruption or disturbance, up the separate air-chimney ; and this ascending power is further increased by erecting a ventilating chimney (shown by dots, in ihe ve':tica! section), of a sufficient height, on the surface of the ground, into the base of which the air-chimney is continued so as to form one uninterrupted air flue, from the top of the ventilating chimney, down to the air-head in the seam of coal. By this means a long experience has shown that a constant draught is established and secured, with the occasional aids of a small furnace or steam jet, which is amply sufficient, in all ordinary cases, to defy wind and weather, and also to produce a current sufficiently strong, that it mav be split, and such portions withdrawn from the main stream of air as may be found requisite to carry on the preparatory work to maintain the get of coal. The air in the gate road and workings is warmed above the temperatiire of the air on the surface, in ordinary mean temperatures, by the heat of the earth, and is consequently rarefied ; this is aided much more than would be generally supposed, by the heat pro- ceedinsr from the numerous workmen, horses, and candles, employed in the mine; and the cuirent is further increased by the escape of the gases, which are specifically lighter than the air,— the air-head forming, with the air-chimney, an uninterrupted and con- tinuous pa-^sage from the workings, and delivering the gas into the ventilating chimney: thus a draught is constantly maintained sufficient for all usual purposes. The weak power of draught that exists in the old sj'stem is materially diminished by the upcast shaft being of a larger size than the air-head through which the downward current of air must pass. The ascending current, in consequence, is languid and slow ; whereas, in the author's judgment, it should have considerable velocity ; and much more important advantages arise from this cause than philosophers account for or will admit Cases may occur in which it is desirable, for temporary purposes, to increase the draught, either when the external air is at a very high temperature, or from other cauai ; and this is at once obtained by adding a furnace, or a steam jet, of any required power, to the ventilating chimney. By means of a fire in this furnace, any degree of rare- faction may be produced that is desired in the ventilating chimney; and it is recom- mended always to build one where the boiler chimney cannot be used, that it may be used if it is wanted. In such cases, the flue of the furnace should be carried up per- pendicularly, for 30 or 40 feet, against the side of the ventilating chimney, before it is MINES, VENTILATION OP. 227 opened into it. This precaution will render a deflagration of the gases, passing up the chimney, impossible, when the furnace is used. The principle of ventilating pits by an air-chimney used for no other purpose than the passage of the gas and the current of air from the workings to the surface, has been adopted by the author, in a more or less perfect form, for more than 30 years, in work- ing the thick and thin mines, and has been found to give a complete and absolute com- mand over the ventilation of every part of the mines. It is only, however, within the last few years, that he has had an opportunity of carrying it through many extensive oits systematically. In the whole of the author's mines, this system of ventilation is now completely carried on. The thick coal is sometimes worked in one pit, and in ♦nother pit^ brooch coal, heathen coal, or the white iron stone lying beneath the coal; and sometimes the thick coal is worked in both. Very little preparation is necessary for this change from one to the other, as the air-chimney reaches to the lowest vein ; and, a stopping being put in at the level of the vein intended to be got, a supply of air may be immediately procured at any required level. The thick coal abi>unde as w^ill be hereafter noticed ; and, as communications between different shafts, by the gate-roads, might be occasionally convenient, these communications may be under the care and sole control of the mine director, who may keep the doors locked, if advisable: the ventilation is thus not materially disturbed. In the different plans for ventilating mines, the merit appears to have been awarded to those more especially who have succeeded in forcing b}'^ any means, either mechanical, or by the use of powerful furnaces, the largest possible quantity of air through the work- ings in a given time. The principle explained in the present paper is totally different, aud diametrically opposite ; for it consists in draining the gas away from the coal before it is worked, and then getting the coal when it is thus drained, and carrying no more air through the mines than is required for light, life, and health. Thus, to illustrate the difference between the two principles of ventilation, supposing that 1,000 cubic feet of gas per minute is emitted by the coal, and passed through the workings, 36,000 cubic feet of air per minute mus^ according to the old method, be passed through the mine, —that is 30,000 feet to dilute the gas, and 5000 feet to supply the workmen, horses, aud candles, in the workings; but, if the whole of this 1000 feet of gas can be carried off by its own levity and intercepted from passing into the workings, then the mine will be better and more safely ventilated by 5000 feet of air j.er minute than by 25,000 feet in the former case ; or, if the whole of tlie gas cannot be intercepted, then in such proportion as the volume of gas can be intercepted and carried away. And I I I .Vni il ■!' 228 MINES, VENTILATION OP. MINES. VENTILATION OF. 229 \ ii I MM; r't I ' ' i r '*' i 1 '1 ii ' Btipposing the opinion of the author to be correct, that the gas can be carried away without parsing into the workings, and that therefore, a very greatly reduced quantity of air is necessary in the mine, it follows that (the gas being of the same specific gravity as atmospheric air, heated up to 612**) when the gas becomes diffused and united with the air, the volume of air and gas so united, is of less specific gravity than the air, and will maintaiu a natural ventilation of considerable power. It may be observed also, that very rapid currents of air through the passages of a mine are always attended with great inconvenience to the workman, and may be attended with great practical danger, from the circumstance, that the union or perfect admixture of the carbu- retted hydrogen with atmospheric air, though very rapid, is not instantaneous; and when in a mine not previously drained of its gas, lai^e quantities of the gas suddenly escaping from powerful " blowers," are driven forwards by a current of air, moving from 7 to 10 feet per second, it is very conceivable that they are not diffused at once, but carried, in some degree, like a cloud of steam, forwards through the mine, till diffusion has brought a portion to the "firing point:" this, meeting with a light, or being driven, as is possible, through the wire of the safety lamp, will inevitably cause an explosion. An objection that was made to the adoption of the system was, the possibility of some disturbance of the brickwork, which separated the air-chimney from the main shaft, either by a violent blow from the ascending skip (which, of course, could not be the case with the guides that are now generally used), or by any accidental explosion that might take place in the mine, which, it was contended, might force it outwards into the main shaft. A mere inspection of the plan must convince any practical person that such an occurrence is impossible. Any force from without would be resisted by the convex surface of the arch which encloses the small shaft, as any operating from within would be as effectually resisted by the convex surface of the main shaft. Not only did no such occurrence ever take place in the numerous pits where the plan has been used without guides ; but even where the air chimney was cut square, possessing so much less resist- ing power, it remains now perfect and uninjured after a lapse of more than thirty years. Another objection was, that the air-chimney was not of sufficient dimensions to ventilate the mine ; and this objection was urged and re-urged in the face of the fact, that the author had expressly stated that cases might occur, where even a seven foot air- shaft might be required and employed to drain very fiery mines. The parties making this objection did not happen to recollect, that, in fact, this air-chimney was precisely of the same area as the air-head, which they themselves always employed, to form the communication between the workings and the upcast shaft. That, in fact, the air- chimney was nothing more nor less than a continuation of the air-head from the work- ings to the surface of the ground ; and consequently, the effect of enlarging the air-chim- ney would be to diminish the velocity of the ascending column, and to lose the increased temperature the air had acquired in passing through the mine. Another objection was, that in some of the thinner veins no upper air-head could be driven at a sufficient height to allow the gas to escape by its own levity, or to prevent it from getting admission to the workings. There may be exceptional cases ; as, for example, if a mine can be supposed to lie upon a perfectly horizontal plane (but the author never saw an instance of a mine to any considerable extent answering this de- scription ; in all mines he has ever seen, the coal forms some angle to the horizon in some direction ; and a very small angle will soon obtain a height of 6 or 7 feet, which is quite sufficient for the present purpose): in that case the air-head, communicating to the up- cast shaft, may be made always to descend to the higher part of the plane, which will be quite sufficient to keep the mine clear from gas, by allowing it to pass off by its own levity. But, even if such a case ever should occur, a remedy may often be obtained, an instance of which has lately occurred to the author. A disturbance in the thick coal vein was found, breaking the coal through and throwing it into a trough 15 yards below its level : of course if the air-head had continued to follow the vein, it must have been depressed below its level to an extent equal to the whole thickness of the coal, which would have formed a barrier against the passage of the gas, like an inverted syphon, which the gas would not have passed. The remedy adopted by the author was, by commencing an air-head from the air-chimney in another measure, the " flying red," that lay 20 yards above the main coal, and continuing it till it had passed over the depressed point ; a communication was then formed to the upper side of this depressed point, which at once established a rising air-head for the whole of the coal on the further side of the depression. It may be perceived that the plan of ventilation here recommended is combined, in some measure, with the method of working the mines, and may be made more perfect and efficient by the adoption of a sound system. The common mode is that of working the mines in " panes," or " panels," leaving pillars or portions of coal to be extracted at a future period ; but this is considered by the author as highly objectionable. The danger of this method must be sufficiently obvious, when it is seen that the air must be forced through the most crooked and winding channels, and compelled to pass along by artificial buildings, or "brattices," the accidental destruction or failure of which may suspend the whole ventilation. But the plan exhibited will show that before any coal is got from the mine, in the inethod recommended by the author, the roads are carried out to the extreme extent that the coal is proposed to be worked, accompanied by their air-heads : by this means the complete drainage of the gas frowi the mass of coal proposed to be worked is ef- fected ; and these roads and their air-heads are originally made at infinitely less ex- pense, and are alwaj's in a safe and secure state, as the excavations commence at the outside of the coal thus intended to be got ; and no brattices are necessary, as double doors may be used in any of these roads down which the air is intended to circulate, either to regulate the quantity, or prevent its passage ; and the current of air may be always brought to act directly upon the working face of the coal. It may be objected, that these pillars must be left for a support, owing to the nature of the roof of the mine ; but this the author has never yet seen, and is disposed to think It never can happen. He is getting veins of coal of 30 feet in thickness (in two successive workings of 15 feet each), also veins of 6 feet, 4 feet and 3 feet thick-nessea. The roofs of these various coals differ in their tenacity, and some of them areextreme- Iv tender, and yet the whole of the coal is extracted from these veins, both the thick- est and the thiimest. both large and small coal, with the greatest facility and safety. The dangers obviated by^ this mode of working are doubly important ; the roof gradu- ally descends as the mine is excavated ; all dangers are left bthind ; and the roof is con- solidated into a compact mass by the weight of the superincumbent otrata ; consequently no " gouf " or hollow is ever formed, and no lodgment of gas can take place. Secondly, no large or small coal being left behind, the heating of the gouf, or the spontaneous combus- tion to which all mines are liable where small coal or slack is left, can never take place. In working mines in panes and pillars (where a part of the coal is left and even- tually lost, the difficulty of obtaining safe ventilation will be understw>d from the following remarks. At Newcastle on-Tyne, the brattices have been all blown down by an explosion, and the workings filled with carbonic acid gas, and no means exist- ing of quickly restoring the ventilation (as at the Felling CoUieryX the pits and workings could not be entered, nor the bodies of the men recovered, for week.«s nay, even months. Every man in the mine, though out of the reach of the explosion, nece:*sarily lost his life by the after-damp. A very recent case in Scotland, at ^itshill, where 69 Jives were lost, is a striking example ; although this pit had a good and dis- tinct upcast shaft, the brattices were destroyed, the air of course proceeded along the shortest and most direct road from the downcast to the upcast shaft, and all the men who had been supplied with air by the diversion of the currents, depending entirely upon brattices (\vhich were destroyed by the explosion), miserably perished, and the whole of the bodies could not be recovered in a week's time. Where shafts are used of large diameter, divided by brattices, and of such large di- mensions as to allow one side of the brattice to form the downcast and the other the upcast shaft, a similar result foUows in the event of an explosion, to that last mention- ed. A part of the brattice (probably at a considerable depth) is ruptuied, and no current of air can be procured to admit of its repair, except by means which involve loss of much time and expense. In the meantime all those who may have been in the pit, at the time (.f the explosion, cannot be approached. The author presumes thatsome idea of economy introduced this system ; but he is satisfied that upon this point an erroneous impression has prevailed.' The expense of si nking these single divided shafts (of the usual diameter of 15 or 16 feet), is so very great, that it has led to the practice of working very extensive areas of coal by means of a single shaft ; and this practice has further led to the different scientific contrivances for impelling the air over these immense areas, by which the ventilation of the works is rendered so much more diffi- cult and uncertain. Taking, for example, a pit of this description, of 15 feet diameter, by which is worked an art a of 2U() acres (and instances* might be adduced where four, five, and six times that quantity has been thus worked), it is evident that the ventilation of a coal mine of this description, where the air passages have been extended to the length of 70 luilea, must be attended with very great danger and vast expense. ^ow, ihe author stjites as his opinion, ai;d thinks he should have no difficulty in pro- vmg it correct, that four shafts might have been sunk on this area of 200 acres, 7 J feet diameter each, in proper posit ionsVith their air chimneys, for comiderably less money than the one shaft cost; and if this can be established, it follows that the 200 acres be- ing divded into sections of 50 acres each, the expense of the underground woik would have been m.-st materially diminished, and that the ventilation might have been effect- ed with much greater ease and security in separate sections of 60 acres each, and the power of raising coal doubled, as there would be always two ascending and two de- scending curves, instead of one. f — , 230 MINT. MINT. 231 1^^' !i i t i To sum up the conditions and principles requisite in carrying out the author's plan eflFectually, it may be stated : — Ist. That the air-head should always open into the highest practicable part of the mines. 2d. Tlie air-head (or what may be properly called the gas-head), by which is meant, the horizontal air or gas-passage, shall always be in continuous communication from the workings to a vertical air chimney, or separate shaft, of 3, 4, 5 or more feet diume ter, whichever shall be required ; but always of sufficient dimensions to carry off the gas and air from the workings. 3d. That the air-head, or gas-head, shall not, in any part of its course, be depressed below the level of its opening into the workings. 4th. That the air-chimney (of such dimensions as the mine requires), by which is meant the vertical air or gas i)as.Hage, shall never be used for any other purpose than the passage of the current of the g"as and air from the workings to the surface; and that it shall be closed from the external air, till it arrives at its point of exit. 6tli. That the vertical air-chimney should be closed at the top, and separated from the shaft, and should then be connected to the ventilated chimney, or the chimney connected by a horizontal flue with the boiler, so that the current of air may not at any time be disturbed or interru|)ted. i • i i 6th. That the gate roads should always be driven to the extreme point to which th« workings of the coal are intended to be extended ; — that the coal may previously be drained of its gas bt-foie any coal is got out; by which means the gate or horse-roads, and the air or gas-head, may be made, and afterwanis be maintained, at considerable less expense, in a safe and secure state, and the gases be gradually drained otf, before it is neeessiiry to get the coal. The author in conclusion states, that the case may be considered as exeptional, rather than general, in which any insurmountable difticulty, in providing the remedy for accidental derangements of the coal strata will present itself; and render it neces- sary to interfere materially with the principles recommended for adoption. MINIUM. (En?, and Fr. ; Red lead; Mennige, Germ.) This pigment is a peculiar oxyde of lead, consisting of two atoms of the protoxyde and one of the peroxyde ; but, as found in commerce, it always contains a little extra protoxyde, or yellow massicot. It is prepared by calcining lead upon a reverberatory hearth with a slow fire, and frequent renewal of the surface with a rake, till it becomes an oxyde, taking care not to fuse it. The calcined mass is triturated into a fine powder in a paint mill, where it is elutriated with a stream of water, to carry off the finely levigated particles, and to deposite them aAersvards in tanks. The powder thus obtained, being dried, is called massicot. It is converted into minium, by being put in quantities of about 50 iwunds into iron trays, 1 foot square, and 4 or 5 inches deep. These are piled up upon the reverberatory hearth, and exposed durins? the nisrht, for economy of fuel, to the residuary- heat of the furnace, whereby the massicot absorbs more oxygen, and becomes partially red lead. This, after being stirred about, and subjected to a similar low calcining heat once and again, will be found to form a marketable red lead. The best minium, however, called orange min£, is made by the slow calcination of good white lead (carbonate) in iron trays. If the lead contains either iron or copper, it affords a minium which cannot be employed with advantage in the manufacture of flint-irlass, for pottery glazes, or for house-painting. Dumas found several samples of red lead which he examined to consist of the chemical sesquioxyde and the protoxyde, in proportions varjing from 50 of the former and 50 of the latter, to 95 3 of the former and 4-7 of the latter. The more oxygen gas it gives out when heated, the better it is, generally speaking. See Naples Yellow. MINT. (Monnaiej Fr. ; Munze, Germ.) The chief use of gold and silver is to serve for the medium of exchange in the sale and purchase of commodities, a function for which they are pre-eminently fitted by their scarcity, by being unalterable by com- mon agents, and condensing a great value in a small volume. It would be very incon- venient in general to barter objects of consumption against each other, because their carriage would be expensive, and their qualities, in many cases, easily injured by external agents, &c. Gold is exempt from siwntaneous change, and little costly in conveyance. Mankind at a verj' early period recognised how much easier it was to exchange a certain weight of gold or silver for objects of commerce, than to barter these objects themselves ; and thenceforth all agreed to pay for their purchases in bars or ingots of these precious metals. But as their intrinsic value depends upon their purity, it be- came necessary to stamp on these bars their standard quality and their weight. The inconvenience of using ingots in general trade, on account of the difficulty of defining fractional values, has determined governments to coin pieces of money, thai is, quantities of metal whose weight and standard were made known and guarantied by the effigies of the prince. It is true, indeed, that kings have become frequently coinera of base money, by altering the weight and purity of the pieces apparently guarantied by their impress. By such reductions, modern coins represent less of the precious metal than they did long ago. The ordomuince of 755, for the coining of sous in France, proves that there was then as much fine silver in a single sous as there is now in a piece of 5 francs. During the last two centuries, indeed, silver coins have been diminished two thirds in weight. But since knowledge has become more generally diffused, it has been shown that these frauds are equally injurious to the prince and to public faith. A sovereign may, it is true, declare by a decree that a shilling-piece is to be held worth five ; but let us consider the consequences of this decree. All the individuals who have rents or capital sums to receive will be ruined, by getting in metallic value only one fifth of what is due to them: for although the nominal value should be the same as what they are entitled to, lae intrinsic value would be but a fifth of the former; so that when they go to purchase the necessaries or comforts of life, the dealer who sells them will at once raise their price five-fold. Each article of merchandise would thus acquire a nominal price 5 times greater ; and he who had received payment of a debt in that money could not with it procure more than one fifth of the goods he could have previously commanded. That fraudulent law would, therefore, favor the debtors at the expense of the creditors ; and as the state is commonly a great debtor, especially when it has recourse to the deprecia- tion of the currency, it is obvious, that however illicit the gain which it makes, it still does gain ; and this is the reason why princes have so often tampered with the mint. But let us examine the other consequences of this decree. If the sovereign is a debtor, he is also a creditor and consumer, and even the most considerable of any. The taxes which he imposes are paid him in this deteriorated money, returned to him at its nominal value ; and the purveyors of his armies, h's buildings, and his household, sell him their commodities only at the actual market price. We may infer from this simple development that the coin with which he pays for any object has the same intrinsic value as the object ; and that the name given to the coin is of no consequence. The prince may call it a crown, a ducat, or a rix-dollai at his pleasure ; and he may assign any value to it that his caprice may suggest, yet this will not affect its value ; for this is fixed beyond his control by the general nature of things. The prince may, indeed, at the outset, have profited by defrauding his creditors, and by authorizing each debtor to imitate him, but he will soon lose whatever he may have gained ; and he will thus learn to his cost that it was bad policy to sacrifice his character by giving an example of a fraud so truly unprofitable in the issue. More- over, he will lose still as much in the following years, because his treasury will receive only one fifth part of the taxes, unless he has quintupled the imposts. It may be said, indeed, that he might do the one thing along with the other. But every one knows that this power is neither generally permitted to princes, nor, if it were, could it be safely exercised. Serious political crises would combine to endanger the stability of the govern- ment ; which besides, as the main consumer in the nation, must lose always as much as it seems to gain. It is therefore manifest, that the alteration of the standard and weight of the coinage is at once a crime and a ruinous action for the sovereign power to commit; and hence such disastrous measures have been long abandoned in all well-regulated states. A gold sovereign is intrinsically worth 20 shillings, minus the cost of coinage ; for were it worth more, all our sovereign pieces would be exported or melted down, to obtain the difference of value, however trifling it might be ; and were it worth less, it would be the source of loss similar to what the state occasions when it depreciates the coin. To comprehend the true value of a coin, we must regard this piece as an article of merchandise, whose value depends, as that of every thing else, on its usefulness, the esteem in which it is held, and the demand for it in the market. Grain increases in value when there are few sellers and many buyers ; gold and silver are in the same pre- dicament. The value of these metals is much augmented, indeed, by the universal cur- rency they obtain when struck into money ; a value additional to what they possess as object 5 of the arts. This value of the precious metals changes with time and place, like that of every merchandise ; their abundance, since the discovery of America, has greatlj lowered their value ; that is, with the same weight of metal, we cannot at the present day purchase the same quantity of corn, land, wool, &c. as formerly. In the countries where silver abounds, this metal has less value, or, in other terms, commodities are dearer. Hence the metal tends to resume its equilibrium in flowing into those places where it is rarer ; which means, that the consumer prefers purchasing his commodities there, rather than In another place, if he can easily transport them to where they arc dearer. ^ It was formerly believed that a country is rich when it has a great deal of gold and silver ; but this popular illusion has passed away. Spain has never been poorer than «ince the discovery of America, because its national industry has been ruined, and the I f •■.^_..=^ 232 MINT. capitals merely passed through its hands to spread over the rest of Europe, from which it was obU'»ed to import every thing that its want of home manufactures made it neces- sary to procure from abroad. We may add to these the prodigalities of the court, which, supposing its wealth inexhaustible, tried to corrupt aU the ministers of the other powers, in furtherance of the chimera of universal dominion. The richest state is that in which there is most industry, whereby the inhabitants may procure every thing indispensable to the conveniences and comfort! of life. Gold as a useful metal, and a medium of exchange, is undoubtedly very precious, and an adequate quantity for these exchanges must be had; but as it is ffood for very little besides, nay, as an excess is even hurtful, it soon begins to fly of itself towards the places where it is more needed or less common. With regard to the relative value of gold and silver, several details have already been given in our view of the mineral wealth of the globe. Three centuries ago, an ounce of gold was worth at London or Paris 10 ounces of silver ; now it may be exchanged for 15 ounces and a half. ^ ^ . . , . j . j _j x: The par of two coins results from the comparison of their weight and standard line- ness. Let us take for an example the conversion of English gold sovereigns worth 20 shillings or a pound sterling, in relation to the French louis of 20 francs. The standard of the sovereign gold is 0-917, fine gold being 1000; its weight is 125,256 gr. English, or 7-980855 grammes; by multiplying this weight into its standard, we have a product of 7-3 18444035; this is, in grammes, the quantity of pure gold contained in the sovereign piece. The piece of 20 francs has a legal standard of 09 ; and multiplyinff this number by the weight of the louis, 6-45161 grammes, we find that it contains 5-806449 of pure metal. We then make this proportion :— « , « ,. »^ As 5-806449 : 20 francs : : 7-31844 : 25-2079 francs; or the value of the English sove- reign is nearly 25-21 francs, in French gold coin. A similar calculation may be made for silver coins. The French rule for finding the par of a foreign gold coin, or its intrinsic value in francs, is to multiply its weight by its standard or titre, and that product by 3*. The par of foreign silver money, or its intrinsic value in francs, is obtained by multiplying its weiffht in grammes by its standard in thousand parts, and by |. The French 5-franc piece has its standard or titre at 0-9, and weighs 25 grammes. The assavina of gold for coin and trinkets requires very delicate management. The French take half a gramme at most (about 7$ grains) of gold, and fuse it with thrice its weight of silver, as already described under Assay. The parting is the next operation. For'this purpose the button of gold and silver alloy is first hammered flat on a piece of steel, and then made feebly red hot in burning charcoal or over a lamp flame. After being thus annealed, the metal is passed through the rolling press, till it be con- verted into a plate about JL of an inch thick. After annealing this riband, it is coiled into a spiral form, introduced immediately into a small matrass of a pear shape, an assay matrass, and about 500 grains of nitric acid, sp. grav. M85, are poured over it. Heat being now applied to the vessel, the solution of the silver and copper alloys ensues, and after 22 minutes of constant ebullition, the liquid is poured off and replaced by an equal quantity of nitric acid, likewise very pure, but of the density 1-28. This is made to boil for about 10 minutes, and is then poureorte(l on bearings between two standards 6, b, bolted down to the ground sills. On the ends of the axes of these wheels are heads ^for the reception of coupling boxes d, d, which unite them to short connecting shafts K l; and these again, by means of coupling boxes, convey motion to the upper rollers e, e, of each pair, at f and g. The middle wheel d upon the main shaft b gives motion to the lower rollers in a similar manner. Thus both the rollei-s «,/ of each frame receive their motion from the main shaft with equal velocity, by means of wheels of large radius, which act with much more certainty than the small pinions usually employed in rolling mills to connect the upper and lower rollers, and cause them to move together. The rolling mill contains four pairs of rollers, each driven by its train of wheel work ; the mill, therefore, consists of two such sets of wheels and rollers as are represented in our figure. The two shafts are situated parallel to each other, and receive their motion from 'the same steam engine. This admirable rolling mill was erected by John Rennie, Esq. The ingots are heated to redness in a furnace before they are rolled. The iwo fur- naces for this purpose are situated before two pairs of rollers, which, from being used to consolidate the metal by rolling whilst hot, are termed breaking-down rollers. Two men are employed in this operation ; one taking the metal from llie furnace with a pair of tongs, introduces it between the rollers ; and the other, catching it as it comes through, lifts it over the top roller, and returns it to his fellow, who puts it through again, having previously approximated the rollers a little by their adjusting screws. After having been rolled in this manner four or five times, they are reduced to nearly two tenths of an inch thick, and increased lengthwise to about four times the breadth of the insot. These plates, while still warm, are rubbed over with a dilnte acid or pickle, to remove the color produced by the heat, and are then cut up into narrow slips across the breadth of the plate, by means of the cir- cular shears ^g. 9*77. This machine is worked by a spur-wheel at the extremity of the main shaft b of the rolling mill (^g. 916.) It consists of a framing of iron a a, supporting two shafts b b. Which are parallel to each other, and move together by means of two equal spur-wheels c c the lower one of which works with the teeth of the great wheel above mentioned, upon the main shaft of the rolling mill. At the extremities of the two shafts, wheels or circular cutters are fixed with their edges overlapping each other a little way. F represents a shelf on which the plate is laid, and advanced forward to present it to the cutter ; and g is a ledge or guide, screwed down on it, to conduct the metal and to regu- late the breadth of the piece to be cut off. Hence the screws which fasten down the ledffe are fitted in oblong holes, which admit of adjustment. The workman holds the plate flat upon the surface f, and pushing it towards the shears, they will lay hold of it, and draw it through until they have cut the whole length. The divided parts are also prevented from curling up into scrolls, as they do when cut by a common pair of shears ; because small shoulders on e and r, behind the cutting edge, keep them straight. Be- hind the standard, supporting the back pivots of the shafts b b of the cutter, is a frame /, with a screw m tapped through it. This is used to draw the axis of the upper cutter d endwise, and keep its edge in close contact with the edge of the other cutter e. The slips or ribands of plate are now carried to the other two pairs of rollers in the rolling mill which are made of case-hardened iron, and better polished than the breaking-down rollers. The plates are passed cold between these, to bring them to exactly the same thickness; whence they are called adjusting or planishing rollers. The workman here tries every piece by a common gauge, as it comes through. This is a piece of steel having a notch in it ; the inside lines of which are ver)' straight, and inclined to one another at a very acute angle. They are divided by fine lines, so that the edge of the plate being pressed into the notch, will have its thickness truly determined by the depth to which it enters, the divisions showing the thickness in fractions of an inch. in roiling the plate the second time, all the plates are successively passed through the rollers; then the rollers being adjusted, they are passed through another time. This is repeated thrice or even four times ; after which they are all tried by the gauge, and thus sorted into as many parcels as there are diflTerent thicknesses. It is a curious cir- cumstance, that though the rollers are no less than 14 inches in diameter, and their frame {>roportioually strong, they will yield in some degree, so as to reduce a thick plate in a ess degree than a thin one ; thus the plates which have all passed through the same rollers, may be of 3 or 4 different degrees of thickness, which being sorted by the gauge into as many parcels, are next reduced to the exact dimension, by adapting the rollers to each parcel. The first of the parcel which now comes through is tried, by cutting out a circular piece with a small hand machine, and weighing it. If it proves either too light or too heavy, the rollers are adjusted accordingly, till by a few such trials they are found to be correct, when all the parcel is rolled through. The trial plates which turn out to be too thin, are returned as waste to the melting-house. By these numerous precautions, the blanks or circular discs, when cut out by the next machine, will be very nearly of the same weight ; which they would scarcely be, even if the gauge determined all the plates to the same thickness, because some being more condensed than others, they would weigh differently under the same volume. A great improvement has been made on that mode of lamination, by the late Mr. Barton's machine for equalizing the thickness of slips of metal for making coin, which has been for several years introduced into the British mint. A side elevation is shown in^g. 978, and a plan in^g. 979. It opeiates in the same way as wire-drawing mechan- isms ; namely, pulls the slips of metal forcibly through an oblong opening, left between two surfaces of hardened steel. The box or case which contains the steel dies, composed of two hardened cylinders, is represented at c in Jig. 978. The pincers employed to hold the metal, and draw it through, are shown at s r. The slips of metal to be operated on by the drawing machine, are first rendered thinner at one end, that they may be introduced between the dies, and also between the jaws of the pincers. This thinning of the ends is effected by another machine, con- sisting of a small pair of rollers, mounted in an iron frame, similar to a rolling-milL The upper roller is cylindrical, but the lower is formed with 3 flat sides, leaving merely portions of the cylinder entire, between these flat sides. The distance between the centres of the rollers is regulated by screws, furnished with wheels on their upper ends, similar to what is seen in the drawing dies at c. The two rollers have pinions on their axes, which make them revolve together ; they are set in motion by an endless strap passing round a drum, upon whose axis is a pinion working into the teeth of a whed fixed upon the axis of the lower roller. The end of a slip of metal is presented between the rollers while they are in motion, not on that side of the roller which would operate to draw in the slip between them, as in the rolling-press above described, but on the contrary side, so that when one of the flat sides of the under roller fronts horizontally the circumference of the upper roller, an opening is formed, through which the slip of metal is to be inserted until it bears against a fixed stop at the back of the rollers. As the rollers continue to turn round, the cylindrical portions come opposite to each other, and press the metal between them, forcing it outwards, and rendering the part which has been introduced between the rollers as thin as the space between their cylindrical surfaces. Thus the end of the slip of metal becomes attenuated enough to pass between the dies of the drawing machine, and to be seized by the pincers. In using the drawing machine, a boy takes hold of the handle « of the pincers, fheir hook of connexion with the endless chain /, /, not shown in the present figure, being dis- engaged, and he moves them upon their wheels towards the die-box c. In this move- ■lent the jaws of the pincers get opened, and they are pushed up so close to the ;|ii 236 MINT. i dicbox that their jaws enter a hollow, which brings thcmnear the dies, enabling them to seize the end of the slip of metal introduced between theni by the action of the pre- paratory rollers. The boy now holds the handle s on the top of the pincers fast, and with his olhei hand draws the handle x backwards. Thus the jaws are closed, and the metal firmly '" .*ii ?1 'm>\ 240 MORDANT. gam for the acidulous ; but so much of them should never be used, as to impede the attraction of the mordant for the cloth. Nor should the thickened mordants be of too desiccative a nature, lest they become hard, and imprison the chemical agent before it has had an opportunity of combining with the cloth, during ihe slow evaporation of its water and acid. Hence the mordanted goods, in such a case, should be hung up to dry in a gradual manner, and when oxygen is necessary to the fixation of the base, they should be largely exposed to the atmosphere. The foreman of the factory ought, there- fore, to be thoroughly conversant wilh all the minutiae of chemical reaction. In cold and damp weather he must raise the temperature of his dry ing-house, in order to com- mand a more decided evaporation ; and when the atmosphere is unusually dry and warm, he should add deliquescent correctives to his thickening, as I have particularized in treating of some styles of calico-printing. But, supposing the application of the mordant and its desiccation to have been properly managed, the operation is by no means complete ; nay, what remains to be done is not the least important to success, nor the least delicate of execution. Let us bear in mind that the mordant is intended to combine not only with the organic fibre, but afterwards also with the colonng matter, and that, consequently, it must be laid entirely bare, or scraped clean, so to speak, that is, completely disengaged from all foreign substances which might invest it, and obstruct its intimate contact wilh the coloring matters. This is the principle and the object of two operations, to which the names of duvging and clearing have been If the mordant applied to the surface (.< the cloth were completely decomposed, and the whole of its base broucht into chemical union wilh it, a mere rinsing or scouring in ■water would suffice for removing the viscid substances added to it, but this never happens, whatsoever precautions may be taken; one portion of the mordant remains untouched, and besides, one part of the base of the portion decomposed does not enter into combination wilh the stuff, but continues loose and superfluous. All these par- ticles, therefore, must be removed without causing any injury to the dyes. If in this predicament the stuff were merely immersed in water, the free portion of the mordant would dissolve, and would combine indiscriminately wilh all the parts of the cloth not mordanted, and which should be carefully protected from such combination, as well as the action of the dye. We must therefore add to the scouring water some substance that is capable of seizing the mordant as soon as it is separated from the cloth, and of forming with it an insoluble compound ; by which means we shall withdraw it from the sphere of action, and prevent its affecting the rest of the stuff, or interfering with the other dyes. This result is obtained by the addition of cow-dung to the scouring bath ; a substance which contains a sufficiently great proportion of soluble animal matters, and of coloring particles, for absorbing the aluminous and ferruginous salts. The heat given to the dung-bath accelerates this combination, and determines an insoluble and perfectly inert coagulum. ».,.,. Thus the dung-bath produces at once the solution of the thickening paste ; a more intimate union between the alumina or iron and the stuff, in proportion to its elevation of temperature, which promotes that union; an effectual subtraction of the undecomposed and superfluous part of the mordant, and perhaps a commencement of mechanical separa- tion of the particles of alumina, which are merely dispersed among the fibres ; a separa- tion, however, which can be completed only by the proper scouring, which is done by the dash-wheel with such agitation and pressure (see Bleaching and Dukgikg) as vastly facilitate the expulsion of foreign particles. See also Bran. Before concluding this article, we may say a word or two about astringents, and especially gall-nuts, which have been ranked by some writers among mordants. It is rather difficult to account for the part which they play. Of course we do not allude to their operation in the black dye, where they give the well known purple-black color with salts of iron ; but to the circumstance of their employment for madder dyes, and especially the Adrianople red. All that seems to be clearly established is, that the asUingent principle or tannin, whose peculiar nature in this respect is unknown, com- bines like mordants with the stuffs and the coloring substance, so as to fix it ; but as this tannin has itself a brown tint, it will not suit for white grounds, though it answers quite well for pink grounds. When white spots are desired upon a cloth prepared with oil and galls, they are produced by an oxygenous discharge, effected either through chlorme oi chromic acid. . v v* i. MORDANT is also the name sometimes given to the adhesive matter by wnicn gold-leaf is made to adhere lo surfaces of wood and metal in gilding. Paper, vellum, taffety, &c., are easily gilt by the aid of different mordants, such as the following : 1. beer in which some honey and gum arable have been dissolved ; 2. gum arable, sugar, and water; 3. the viscid juice of onion or hyacinth, strengthened with a little gum arable. When too much gum is employed, the silver or gold leaf is apt to crack in the drying of the mordant. ^ A Uttle carmine should be mixed with the above colorless MOROCCO. 241 liquids, to mark the places where they are applied. The foil is applied by means of « dossil of cotton wool, and when the mordant has become hard, the foil is polished with the ^>ame. The best medium for sticking gold and silver leaf to wood is the following, called mix- tion by the French artists : — 1 pound of amber is to be fused, with 4 ounces of mastic io tears, and 1 ounce of Jewish pitch, and the whole dissolved in 1 pound of linseed oil ren- dered drying by litharge. Painters in distemper sometimes increase the effect of their work, by patches of gold leaf, which they place in favorable positions; they employ the above mordant. The manufacturers of paper hangings of the finer kinds attach gold and silver leaf to them by the same varnish. MOROCCO. See Leathkr. MORPHIA (Morphine, Fr. ; Moi-phin, Germ.) is a vegeto-alkali which exists asso- ciated with opian, codeine, narcotine, meconine, meconic acid, resin, gum, bassorine lig- nine, fat oil, caoutchouc, extractive, &.c. in opium. Morphia is prepared as follows; Opium in powder is to be repeatedly digested with dilute muriatic acid, slightly heated, and sea-salt is to be added, to precipitate the opian. The filtered liquid is to be super- saturated with ammonia, which throws down the morphia, along with the meconine. resin, and extractive. The precipitate is to be washed with water, heated, and dissolved in dilute muriatic acid ; the solution is to be filtered, whereby the foreign matters are sepa- rated from the salt of morphia, which concretes upon cooling, whilr the meconine remains in the acid liquid. The muriate of morphia having been squeezed between folds of blot- ting pai)er, is lo be sprinkled with water, again squeezed, next dissolved in water, and decomposed by water of ammonia. The precipitate, when washed, dried, dissolved in alcohol, and crystallized, i» morphia. These oiystals, which contain 6-32 per cent, of combined water, are transparent, color- less, four-sided prisms, without smell, and nearly void of taste, fusible at a moderate heat, and they concrete into a radiated translucent mass, but at a higher temperature they grow purple-red. Morphia consists of 72*34 of carbon ; 6*366 of hydrogen j 5 of azote ; and 16-3 of oxygen. It burns wilh a red and very smoky flame, is stained red by nitne acid, is soluble in 30 parts of boiling anhydrous alcohol, in 600 parts of boiling water, but hardly if at all in cold water, and is insoluble in ether and oils. The solutions have a strong bitter taste, and an alkaline reaction upon litmus paper. The saline com- pounds have a bitter taste, are mostly cryslallizable, are soluble in water and alcohol (but not in ether), and give a blue color to the peroxyde salts of iron. It is a very poi- sonous substance. Acetate of morphia is sometimes prescribed, instead of opium, in medicine. Preparation of Morphia, — The aqueous extract of opium is to be concentrated by evaporation, and mixed with chloride of tin, till no further precipitate appears. The liquid is then allowed to settle, is poured-off, the precipitate is washed, and the wash- ings mixed with the poured-off liquid. To this mixture is then added ammonia, and the precipitate which it produces is to be digested with ether, in order to remove the narcotine ; and then w ith alcohol, as long as the latter acquires a bitter taste. The alcohol being then partially removed by distillation, the pure morphia is obtained in the form of crystals. MORTAR, HYDRAULIC, called also Roman Cement, is the kind of mortar used for building piers, or walls under or exposed to water, such as those of harbors, docks, Ac The poorer sorts of limestone are best adapted for this purpose, such as contain from 8 to 25 per cent of foreign matter, in silica, alumina, magnesia, ; fine black wax, or with the fusible alloy of D'Arcet, animpifssion of mother of pearl. It will possess the iridescent appearance. Mother of pearl is very delicate to work, but It may be fashioned by saws, files, and drills, with the aid sometimes of a corrosive acid, such as the dilute sulphuric or muriatic ; and it is polished by colcothar of vitriol MO THE K- WATER is the name of the liquid which remains after all the salts that Will regularly crystallize have been extracted, by evaporation and cooling, from any saline solution. MOUNTAIN SOAP (Savon de montagne, Fr. ; Bergseife, Germ.) is a tender mineral, ■oft to the touch, which assumes a greasy lustre when rubbed, and falls to pieces in water. It consists of silica 44, alumina 26-5, water 20-5, oxyde of iron 8, lime 0-5. It occurs in • be(*s, alternating with different sorts of clay, in the Isle of Skye, at Billin in Bohemia, &.C. It has been often, but improperly, confounded with stratite. , MUCIC ACID (Jcide mucique, Fr. ; SchUimsaure, Germ.) is the same as the saclactic acid of Scheele, and may be obtained by digesting one part of gum arable, sugar of milk, or peclic acid, with twice or thrice their weight of nitric acid. It forms white granular ' cr)'«tals, and has not been applied to any use in the arts. MUCILAGE is a solution in water of gummy matter of any kind. MUFFLE is the earthenware case or box, in the assay furnaces, for receiving the • cupels, and protecting them from being disturbed by the fuel. See Assay and Furnace. MUNDIC is the name of copper pyrites among English minci-s. * MUNJERT is a kind of madder srown in several parts of India. MURIATIC or HYDROCHLORIC ACID ; anciently manne acid, and npirit of »aU, (jSctde hydrocklorique, and Chlorhydrique, Fr. ; Salzsaure, Germ.) This acid is now extiacU ed from sea-salt, by the action of sulphuric acid and a moderate heat ; but it was originally obtained from the salt by exposin? a mixture of it and of common clay to ignition in an earthen retort. The acid gas which exhales, is rapidly condensed by water. 100 cubic mches of water are capable of absorbing no less than 48,000 cubic inches of the acid • gas, whereby the liquid acquires a specific gravity of 1-2109 ; and a volume of 142 cubic inches. This vast condensation is accompanied with a great production of heat, whence It becomes necessary to apply artificial refrigeration, especially if so strong an acid as the above is to be prepared. In general, the muriatic acid of commerce has a specific gravity varying from M5 to 1-20; and contains, for the most part, considerably less than 40 parts by weight of acid gas in the hundred. The above stronger acid contains 42-68 per cent, by weight ; for since a cubic inch of water, which weighs 252-5 grains, has absorbed 480 cubic inches = 188 grains of gas ; and 2525 -f 188 = 4405 ; then 440-5 : 188 : : 100 : 42-68. In general a very good approximation may be found to the per centage of real muriatic acid, in any liquid sample, by multiplying the decimal figures of the specific gravity by 200. Thus for example, at M62 we shall have by* this rule 0-162 X 200 = 32-4, for the quantity of gas in 100 parts of the liquid. Muriatic • acid gas consists of chlorine and hydrogen combined, without condensation, in equal vol- umes. Its specific gravity is 1-247, air = 1-000. By sealing up muriate of ammonia and sulphuric acid, apart, in a strong glass tube re- ' curved, and then causing them to act on each other. Sir H. Davy procured liquid muriatic acid. He justly observes, that the generation of elastic substances in close vessels, either • With or without heat, ofiers much more powerful means of approximating their molecules than those dependant on the application of cold, whether natural or artificial ; for as gases diminish only ~L_ m volume for every degree of Fahrenheit's scale, beginning at ordinary temperatures, a very slight condensation only can be produced by the most powerful freezing mixtures, not half as much as would result from the application of a stron*' flame to one part of a glass tube, the other part being of ordinary temperature ; and when, attempts are made to condense gases into liquids by sudden mechanical compression, the heat instantly generated presents a formidable obstacle to the success of the experiment; whereas m the compression resulting from their slow generation in close vessels, if the process be conducted with common precautions, there is no source of difficulty or danger: and it may be easily assisted by artificial cold, in cases where gases approach near to that point of compression and temperature at which they become vapors.— PAti. Trans, The muriatic acid of commerce has usually a yellowish tinge, but when chemically pur« It is colorless. It fumes strongly m the air, emitting a corrosive vapor of a peculiar - smell. The characteristic test of muriatic acid in the most dilute slate, is nitrate of silver, which causes a curdy precipitate of chloride of silver. The preparation of this acid upon the great scale is frequently effected in this ^""•— 246 MURIATIC ACID. by acting upon sea-salt in hemispherical iron pots, or in cast-iron cvlindere with con. eentratel sulphuric acid ; taking 6 parts of the saU to 5 of the Icfd ^ 'Se ^iTth V^^^^ two inches m diameter each, into the one of which the acid is poured bv a funnel in 5nctZ?hrj;« ''°'' ^''l ^"*'' '^t''^^'' .* ^""' «^^''' ^' Btone-ware tube, is Led, fo^con flTriu A ^}'^''S^S^^ muriatic gas into a series of large globes of bottle g ass one- ^ rd filled with water and laid on a sloping sand-bed. A wlek is commonl^emplov ed for working off each i>ot ; no heat being applied to it till the second day. ^ ^ ^ Vr.^X '^^T'''' °^ ^^"^^^ ^y sulphuric acid, was at one time earned on by some French manufacturers m large leaden pans, 10 feet long, 5 feet broad, and a foot dTr! TZtZffT'^^ i""1' «"^ ^"^^- The disengaged^acid gas was made to circS in a conduit of glazed bricks, nearly 650 yards long, where it was condensed by a sheet f sW nf^f f 9nf '^ '^*"' which flowed slowly in the opposite direction of the gas down w«l it V ^^^' ^ ^^^ !"** ^^ ^^'' '^^"^^ "^^-^^^^ '^^ apparatus, the muilalic acid was as strong as possible, and pretty pure ; but towards the other end, the water was narUly acidulous. The condensing part of this apparatus was therefore tolerably com- plete ; but as the decomposition of the salt could not be finished in the leaden pans, the Jfjfr^ ♦"^ ^^ ^"^ be drawn out of them, in order to be completely decomposed in a feverberatory furnace ; m this way nearly 50 per cent, of the muriatic acid was lost And besides, the great quantity of gas given ofl' during the emptying of the lead-chamberi was apt to suffocate the workmen, or seriously injured their lungs, causing severe Lemoptysis. The employment of muriatic acid is so inconsiderable, Lnd the loss of it mcurred m the preceding process is of so little consequence, that subsequently, both in i^^?u ^f ■" E"S^*"^» sulphate of soda, for the soda manufacture, has been procured with the dissipation of the muriatic acid in the air. In the method more lately resorted to, the gaseous products are discharged into extensive vaults, where currents of water condense them and carry them off into the river. The surrounding vegetation is thereby •aved m some measure from being burned up, an accident which was previouslv sure to happen when fogs precipitated the floating gases upon the ground. At Newcastle Liverpool, and Marseilles, where the consumption of muriatic Lid bears no pro^rt in to the manufacture of soda, this process is now practised upon a vast scale. *^ ^ " rhe apparatus for condensing muriatic acid gas has been modified and changed, of late years, in many diflerent ways. * ' The Bastringue apparatus. At the end of a reverberatory furnace, (see Coppeh. •MELTING OF and SoDA, MANUFACTrKE OF,) a rectangular lead trough or pan, about 1 foot f ?'«fr* 7f^ ^"?^ ^^ 'i'^.* ^^ *^^ ^"^^"^•' «^ '^^ ^"'»»<=e^ ^^^'\ about 5 feet wide! •nd 6^ feet long, is incased in masonn', having its upper edges covered with cast-iron frnif' th' il'' f"*^ ^^^^r^ "P^!! * ^^""^^ '""'^^ *^« P««^?« «^ the flame, as it escapes from the reverberatory. The arch which covers that pan forms a continuation of Ihe roof of the reverberatory, and is of the same height. The flame which proceeds from the furnace containing the mixture of salt and sulphuric acid is made to escape between thlt^ht Whtn"]^^'^ ""^^^ ••■''" ?^^''' ""' ^'^ '''^^'* *^^°"=»> ^ P^^^«?^ «"^y 4 inches Zt^&A , ^ 5"™*? *"■ ^""^ '^^P^''" ^^^^•^ the extremity of the pan, they are reflected downwards and made to return beneath the bottom of the pan, in a flie, which IL^^K-''^"^' ^'Z^*^ '°.^\^° ^^^^ the smoke into two lateral flues, which terminate in the chimney. The pan is thus surrounded as it were with the heat and flame dischar-ed from the reverberatory furnace. See Evaporation. A door is opened near the end'of Sr .wu ^%;,"troducing the chaije of sea-salt, amounting to 12 bags of 2 cwts. each, or tJr 1 ^his door is then luted on as tightly as possible, and for every 100 parts of salt. 110 of sulphuric acid are poured in, of specific gravity 1-594, containing 57 per cent, of dry acid. This acid is introduced through a funnel inserted in the roof of the furnace pecomposition ensues, muriatic acid gas mingled with steam is disengaged, and is conl ducted through 4 stone-ware tubes into the refrigerators, where it is finally conden^ These refrigerators consist of large stone-waie carboys, called dame-jeans irFmnce to the number of 7 or 8 for each pipe, and arranged so thit the neck of the one commun ° cates with the body of the other; thus the gas must traverse the whole series, rdZ, ""^1"^ measure condensed by the water in them, before reachin- the last . When the operation is finished, the door opposite the pan is opened, and 'the re«;iduum in It IS discharged^in the form of a fluid magma, upon a square bed of br cks, exS ttl anTrrVvd^'^r^'L^P^'^^^^""^^"^^^ «" ^^""- ^"^ ^^ then broken into fi^! mcnts and carried to the soda manufactory. The immense quanlitv of gas exhaled in discharging the pan, renders this part of the operation very Vin/ul to Teworkme^^ Wd wasteful in reference to the production of muriatic acid. "^ The dilBculty of luting securely the cast-iron plates or fire tiles which cover the pan, the im,>ossibility of com! r*«Tl L ?K°T''^'''" ^^^'J^ ^^^'^ ''"'^^ ^he residuum mist be run off in a liquid .tate, finally, the damage sustained by the melting and corrosion of the lead, &c , are lunong the causes why no more than 80 or 90 parts of muriatic acid at M70 are collected .V MURIATIC ACID. 247 equivalent to 25 per cent, of real acid for every lOO of salt employed, instead of muck naore than double that quantity, which it may be made to yield by a well conducted chemical process. The cylinder apparatus is now much esteemed by many manufacturers. Jf%a. 98S represents, m transverse section, a bench of iron cylinder retorts, as built up in a proper furnace for producing muriatic acid; and/^. 983, a longitudinal section of one retort with one of its carboys of condensation, a is the grate ; 6, a fireplace, in which two iron cylinders, c c, are set alongside of each other. They are 5| feet long, 20 inches in diameter, about f of an inch thick, and take 1-6 cwts. of salt for a charge : d is the ash- pit ; e, «, are cast-iron lids, for closing both ends of the cylin- ders ; / is a tube in the pos- terior lid, for pouring in the sulphuric acid; g is another tube, in the anterior lid, for the insertion of the bent pipe of hard glazed stone- ware A; i is a three-necked stone-ware carboy; fc is a tube of safety; /, a tube of communication witk the second carboy ; m m,mfn, are the flues leading to the A A u chimney n. After the salt has been introduced, and the fire kindled, 83J per cent, of its weight of sulphuric acid, of spec. grav. 1-80, should be slowly poured into the cyUnder through H lead funnel, with a syphon-formed pipe. The three-necked carboys may be either piaced in a series for each retort, like a range of Woulfe's bottles, or all the carboyt of the front range may be placed in communication with one another, while the last car- boy at one end is joined to the first of the second range ; and thus in succession. Thef must, be half filled with cold water ; and when convenient, those of the front row at least, should be plunged m an oblong trough of running water. The acid which con- denses m the carboys of that row is apt to be somewhat contaminated with sulphuric acid muriate of iron, or even sulphate of soda; but that in the second and thiid will be found to be pure. In this way 100 parts of sea-salt will yield 130 parts of muriatic acid. r T^' V-' ^^^l 7^'^'' ^^^ sulphate of soda in the retort wiU afford from 208 to 210 of that salt m crystals. It is proper to heat all the parts of the cylinders equably, to ensure the simultan«>n. decomposition of the salt, and to protect it from ihe acid ; for the hotter the iron, andSJ stronger the acid, the less erosion ensues nn^fpTZtTJt?' """''^ ^tj'^.'' ^^ ^^*"? ^"^* ^y the construction of their furnaces oppose to the flame as many obstacles as they can, and make it perform numerous circuS ' tions round the cylinders ; but this system is bad, and does nbt even effect the desired economy, because the Passage^ being narrow, impair the draught, and become speedUy choked up with the soot, which would be burned profitably in I freer space; the d^n; position also, b«;;? unequally performed, is less perfect, and the cylinders ire more in- jured. It is better to make the flame envelope at once the body of the cylinder; after 248 MURIATIC ACID. •■( I jrWch it may circnlate beneath the vault, in order to gire out a portion of its caloria Defore it escapes at the chimney. ^ ^ .;.V\l ^""^ ^^T^^ ^^ ^"'^'^' kindled but lowered as soon as the distillation commences ; and then continued moderate t. I the evolution of gas diminishes, when it must be heated soinewha strongly to finish the decomposition. The iron door is now removed to extract the «ulphate ot soda, and to recommence another operation. This sulphate ought to be white and uniform, exhibiting in its fracture no undecomposed sea-salt J.1.IU1J muriatic acid has a very sour corrosive taste, a pungent suffocalin*' ^mell and acts very powerfully upon a vast number of mineral, Vegetable, and an?mal%Xtances It ,s much employed for making many metallic solutions? and in combinaTon with n" trie' acid, 11 forms the aqua regia of the alchemists, so called from its property of dissolving Table of Muriatic Acid, by Dr. Ure. Acid of l'^( in 100 100 99 98 97 96 95 94 93 92 91 90 89 88 87 86 85 84 83 82 81 80 79 78 77 76 75 74 73 72 71 70 69 68 67 Specific gravity. 1-2000 1-1982 1-1964 1-1946 1-1928 1-J910 1-1893 M875 1-1857 1-1846 1-1822 1-1802 11782 1-1762 1-1741 M72J 1-1701 Chlo- rine. 1681 1661 1641 1 1 1 1-1620 M599 M578 1-1557 M536 1-1515 1-1494 1-1473 M4.52 11431 M410 M389 1-1369 M349 39-675 39-278 38-882 38-485 38-089 37-692 37-296 36-900 36-503 36-107 35-707 35-310 34-913 34-517 34-121 33-724 33-328 32-931 32-535 32- 136 31-746 31-343 30-946 30-550 30-153 29-757 29-361 |28-964 J28-567 28-171 ,27-772 ;27-376 j 26-979 i 126-583 Muriatic Gas. 40-777 40-369 39-961 39-554 39-146 38-738 38-330 37-923 37-516 37-108 36-700 36-292 35-884 35-476 35-068 34-660 34-252 33-845 33-437 33-029 32-621 32-213 31-805 31-398 30-990 30-582 30-174 29767 29-359 |28-951 28-544 28-136 27-728 27-321 Acid of 120 in 100 66 65 64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 Specific gravity. 1328 1308 1287 1267 1247 1-1226 1206 1185 1164 1143 1123 1102 1082 1061 1041 1020 1000 1-0980 1-0960 1-0939 10919 1-0899 1-0879 1-0859 1.0838 1-0818 1-0798 1-0778 1-0758 1-0738 10718 10697 1-0677 1-0657 Chlo- rine. Muriatic Gas. 26-186 25-789 25-392 24-996 24-599 24-202 23-805 23-408 23-012 22-615 22-218 21-822 21-425 21-028 20-632 20-235 19-837 19-440 19-044 18-647 18-250 17-854 17-457 17-060 16-664 16267 15-870 15-474 15-077 14-680 14-284 13-887 13-490 13-094 26-913 26-505 26-098 25-690 25-282 24-874 24-466 24-058 23-050 23-242 22-834 22-426 22-019 21-611 21-203 20-796 20-388 19-980 19-572 19-165 18-757 18-349 17-941 17-534 17-126 16-718 16-310 15-902 15-494 15-087 14-679 14-271 13-863 13-456 Acid I c ., n 100 g'a^ity- 32 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 U 13 12 11 10 9 8 7 6 6 4 3 2 1 1 0637 1-0617 1-0597 1-0577 1-0557 1-0537 1-0517 1-0497 1-0477 1-0457 10437 1-0417 1-0397 1-0377 1-0357 1-0337 1-0318 1-0298 10279 1-02.59 1-0239 1-0220 1-0200 1-0180 1-0160 1 0140 1-0120 1-0100 1-0080 1-0060 1-0040 1-0020 Chlo- I Muriatic rine. Gas. 12-697 12-300 11-903 11-506 11-109 10-712 10-316 9-919 9-522 9-126 8-729 8-332 7-935 7-538 7-141 6-745 6-348 5-951 5-554 5-158 4-762 4-365 3-968 3-571 3-174 2-778 2-381 1 984 1-588 1-191 0-795 0-397 13-049 12-641 12-233 11-825 11-418 11010 10-602 10-194 9-786 9-379 8-971 8-563 8-155 7-747 7-340 6-932 6-524 6116 5-709 5-301 4-893 4-486 4-078 3-670 3-262 2-854 I 2-447 I 2-039 1-631 1-224 0-816 0-408 i In treating of soda, we shall have occasion to comment upon the formation of muri. atic acid ; and therefore it is unnecessary to enter into the details of that operation Here. Ihe purest commercial muriatic acid commonly contains sulphureous acid in considerable quantity, which unfits it for many purposes, and ought therefore to bA guarded agamst; but more than this, when made from sulphuric acid contaiuin^ ar! senic, It IS invariably contaminated with that poisonous substance, and hence those •persons who are in the habit of making what is called digestive bread, bv an Admix- ture of bicarbonate of so.la and muriatic acid with the flour they employ, cannot be too careful m going to none but the moat respectable sources for tlieir acid • as an enormous amount of rough muriatic acid is constantly passing through the market positivelv loaded with arsenious impurity. For the same reason, as chloride of lime is manufac- tured from the acid, it must be regarded with a cautious eye; as, during the action of ■uch muriatic acid upon peroxide of manganese, a highly volatUe chloride of arsenic # .1 MUSQUET. pajsses off with the chlorine gas, and is condensed like it by the lime. Since, however, this, in the end, becomes arsenite of lime, a salt almost insoluble in water, the tendency to mischief is greatly diminished. Nevertheless, as in some medico-legal works it is recommended to sprinkle cadaverous exhumations with chloride of linie, the ends of justice may easily be perverted or prevented, if due care be not employed to ascertain beforehand that the chloride of lime is pure. Very little indeed of that to be met with in commerce will bear a careful analytical investigation. MURIATES were, till the great chemical era of Sir II. Davy's researches upon chlo- rine, considered to be compounds of an undecompounded acid, the muriatic, with the different bases ; but he proved them to be, in reality, compounds of chlorine with the metals. They are all, however, still known in commerce by their former appellation. The only muriates much used in the manufactures are, Muriate of ammonia or Sal-am- moniac; mnriated peroxide of mercury. Mercury, bichloride of; muriate of soda, or chlo- ride of sodium, see Salt; muriate of tin, see Calico-Prixting and Tin ; Suhmuriate of mercury or Calomel. MUSK (J/m«c, Fr. ; Moschu^, Germ.); is a peculiar aromatic substance, found in a sac between the navel and the parts of generation of a small male quadruped of the deer kind, called by Linnaeus Moschus moschifcrus, which inhabits Tonquin and Thibet. The color of musk 18 blackish-brown; it is lumpy or granular, somewhat like dried blood, with which substance, indeed, it is often adulterated. The intensity of its smell is almost the only criterion of its genuineness. When thoroughly dried it becomes nearly scentless ; but it recovers its odor when slightly moistened with water of am- monia. The Tonquin musk is most esteemed. It comes to us in small bags covered with a reddish-brown hair ; the bag of the Thibet musk is covered with a silvery -gray hair. All the analyses of musk hitherto made teach little or nothing concerning its active or essential constituent. It is used in medicines, and is an ingredient in a great many perfumes. The musk deer, from the male of which animal species the bag containing this valu- able dru^ is obtained, is a native of the mountainous Kirgesian and Langorian steppes of the Altai, on the river Irtish, extending eastwards as far as the river Jenesi and Lake Baikal ; and generally of the mountains of Eastern Asia, between 30° and 60° of N. Lat. Two distinct kinds of musk are known in commerce, the first being the Ciiinese Ton- quin, Thibetian or Oriental, and the Siberian or Russian. The Chinese is regarded by l)r. Goebel as the result of ingenious adulterations of the genuine article by that crafty people. The Russian musk is genuine, the bags never being opened, are consequently never sewn, nor artificially closed, like those imported into London from China. The former is sometimes so fresh, that moisture may be expressed from the bag by cutting through its fleshy side. The interior mass is frequently of a soft and pappy consist- ence ; but the surface of the bag is perfectly dry. The Chinese bags are found invari- ably to have been opened and again glued together, more or less neatly ; though sometimes the stitches of the sewing are munifest, Mr. Diyssen, an eminent merchant at St Petersburgh, states that during the many years he has been in the trade, al- though he has received at a time from 100 to 200 ounces from London, yet in no case whatever has he met with a bag which had not been opened, and closed with more or less ingenuity. The genuine contents seem to have been first removed, modified, and replaced- M. Guibourt gives the following as the constituents of a Chinese musk bag: 1, water; '2, ammonia; 3, solid fat or stearine; 4, liquid fat or elaine; 5, cholesterine ; 6, acid oil, combined with ammonia; 7, volatile oil; 8-10, hydrochlorates of ammonia,' potassa, and lime; 11, an undetermined acid; 12, gelatine; 13, albumen; 14, fibrine; 15, carbonaceous matter, soluble in water; 16, calcareous salt; 17, carbonate of lime* 18, hairs and sand. * From June 1841 to June 1842, a duty of &d. per oz. was paid at the port of London alone upon 969 ounces of musk. The prices of grain musk of the best quality (the matter without the bag) varies from 60». to 95«. per oz. There is a superior musk imported now from the United States, which is nearly free from the carbonate of lime, so abundant in the bags of the Siberian musk. MUSLIN, is a fine cotton fabric, used for ladies' robes; which is worn either white dyed, or printed. * MUSQUET. It is now twenty-two years since the Hon. Board of Ordnance, with the view of introducing the use of percussion fire-arms into the British Army em-, ployed nie to investigate experimentally the best njode of preparing the priming powder for that purpose. The result of these experiments was presented in a report the sub- stance of which IS given under the article Fulminate in this Dictionar}-. During this long interval, Mr. Lovell, inspector of small arms for her Majesty's service, and director of the Royal manufactory, at Enfield Chase, has directed his ingenious mind to the construction of a sure, simple, and strong musquet, with whicli, under his able •uperintendence, the whole of her Majesty's soldiers are now provided. He had also Vou IL 250 MUSQUET. fiiruished them with a shorty but clear set of instructions for the cleaning and man- ^ement of these excellent arms, illustrated by a series of wood engravings. Fr^ m thii little work, the following notice is copied. Fig. 984. The barrel, reduced to one-seventh size, a, the breech ; h, the nipple-seat or lump; c, the back-sight; d, the back loop; e, the middle loop; /, the swivel-loop; g^ the front-loop with the bayonet spring attached; h, the front sight; t, the muzzle. Fig. 985. The breech-pin, half size ; a, the tang ; b, the neck ; c, the screw threads : a, the face. 984J 988 ^^^ I*' Fig. 986. The bayonet-spring, two ways, half size, o, the shank: h, the neck; e; the hook ; rf, the mortice. ftg.OSt The nipple, full size, a, the cone; 6, the squares t c, the shoulder; a. Che screw-threads j «, the touch-hole. MYRICINE. Fig. 988. The rammer, reduced to one-seventh size, a, the head ; 6, the shaft ; c^ the screw-threads. Fig. 989. The lock outside, half size, a, the plate; 6, the cock; c; the tumbler-pin ; dy the hollow for the nipple seat Fig. 990. The lock inside, half size, showing all the parts in their places with the cock down at bearer, c, the main-spring j b, the sear-spring; c, the sear; d, the tumbler; the e, the bridle; /, the main-spring; g, the sear-pin; h, the sear-spring-pin; t. bridle -pin. o «- » » MUST is the sweet juice of the grape. MUSTARD (Moutarde, Ft. ; Sen/, Germ.) is a plant which yields the well-known seed used as a condiment to food. M. Lenormand gives the following prescription for preparing mustard for the table. With 2 |H)unds of very fine flour of mustard, mix half an ounce of each of the follow- ing fresh plants ; parsley, chervil, celerj', and tarragon, along with a clove of garlic, and twelve salt anchovies, all well minced. The whole is to be triturated with the flour of mustard till the mixture becomes uniform. A little grape-must or suffar is to be added, to give the requisite sweetness; then one ounce of salt, with sufficient water to form a thinnish paste by rubbing in a mortar. With this paste the mustard pots being nearly filled, a redhot poker is to be thrust down into the contents of each, which rem^oves (it is said) some of the acrimony of the mustard, and evaporates a little water, so as to make room for pouring a little vinegar upon the surface of the paste. Such table mustard not only keeps perfectly well, but improves with age. The mode of preparing table mustard patented by M. Soyes, consisted in steeping mustard seed m twice its bulk of weak wood vinegar for eight days, then grinding the whole into paste m a mill, putting it into pots, and thrusting a redhot poker' into each of them. MUTAGE is a process used in the south of France to arrest the progress of fermenta- tion in the must of the grape. It consists either in diffusing sulphurous acid, from burn- ing sulphur matches m the cask containing the must, or in adding a little sulphite (not sulphate) of lirne to it. The last is the best process. See Fermentation. MYRICINE is a vegetable principle which constitutes from 20 to 20 per cent, of the weight of bees-wax, being the residuum from the solvent action of alcohol upon lb»l 252 NAILS. 4 : substance. It is a grayish-white solid, which may be vaporized almost without alter- ation. MYRRH is a gum-resin, which occurs in tears of different sizes; they are reddish- brown, semi-transparent, brittle, of a shining fracture, appear as if greasy under the peslle, they have a very acrid and bitter taste, and a strong, not disagreeable, smell. Myrrh flows from the incisions of a tree not well known, which grows in Arabia and Abyssinia, supposed to be a species of amyria or mimosa. It consists of resin and gum in proportions stated by Pelletier at 3 1 of the former and 66 of the latter j but by Braconot, at 23 and 77. It is used only in medicine. N. NACARAT is a term derived from the Spanish word nacar, which signifies mothei of pearl ; and is applied to a pale red color, with an orange cast. See Calico-printing. The nacarat of Portugal or Bezetta is a crape or fine linen fabric, dyed fugitively of the above tint, which ladies rub upon their countenances to give them a roseate hue. The Turks of Constantinople manufacture the brightest red crapes of this kind. See Rouge. NAILS, MANUFACTURE OF. (C/ou, Fr. ; Nagel, Germ.) The forging of nails was till of late years a handicrail operation, and therefore belonged to a book of trades, rather than to a dictionary of arts. But several combinations of machinery have been recently employed, under the protection of patents, for making these Vseful implements, with little or no aid of the human hand ; and these deserve to be noticed, on account both of their ingenuity and importance. As nails are objects of prodigious consumption in building their block-houses, the citizens of the United States very early turned their mechanical genius to good account in the construction of various machines for makins them. So long since as the year 1810, it appears, from the report of the secretary of their treasury, that they possessed a machine which performed the cutting and heading at one operation, with such rapidity that it could turn out upwards of 100 nails per minute. « Twenty years ago," says the secretary of the state of Massachusetts, in that report, " some men, then unknown, and then in obscurity, began by cutting slices out of old hoops, and, by a common vice griping these pieces, headed them with several strokes of the hammer. By progressive improvements, slitting-mills were built, and the shears and the heading tools were perfected ; yet much labor and expense were requisite to make nails. In a little time Jacob Perkins, Jona- than Ellis, and a few others, put into execution the thought of cutting and of heading nails by water power ; but, being more intent upon their machinery than upon their pecuniary affairs, they were unable to prosecute the business. At different times other men have spent fortunes in improvements and it may be said with truth that more than one mil- lion of dollars has been expended ; but at length these joint efforts are crowned with com- plete success, and we are now able to manufacture, at about one third of the expense that wrought nails can be manufactured for, nails which are superior to them for at least three fourths of the purposes to which nails are applied, and for most of those purposes they are full as good. The machines made use of by Odiorne, those invented by Jonathan Ellis, and a few others, present very fine specimens of American genius. « To northern carpenters, it is well known that in almost all instances it is unneces- sary tc bore a hole before driving a cut nail ; all that is requisite is, to place the cutting edge of the nail across the grain of the wood ; it is also true, that cut nails will hold bet- ter in the wood. These qualities are, in some rough building works, worth twenty per cent, of the value of the article, which is equal to the whole expense of manufacturing. For sheathing and drawing, cut nails are full as good as wrought nails ; only in one respect are the best wrought nails a little superior to cut nails, and that is where it is ne- cessary they should be clinched. The manufacture of cut nails was born in our country, and has advanced, within its bosom, through all the various stages of infancy to manhood; and no doubt we shall soon be able, by receiving proper encouragement, to render them superior to wrought nails in every particular. " The principal business of rolling and slitting-mills, is rolling nail plates ; they also serve to make nail rods, hoops, tires, sheet iron, and sheet copper. In this State we have not less than twelve. « These mills could roll and slit 7000 tons of iron a year ; they now, it is presumed, roil and slit each year about 3500 tons, 2400 tons of which, probably, are cut up into nails and brads, of such a quality that they are good substitutes for hammered nails, and, in fact, have the preference with most people, for the following reasons ; viz., on account of the sharp corner and true taper with which cut nails are formed ; they may be driven into harder wood without bending or breaking, or hazard of splitting the wood, by which NAILS. 258 the labor of boring is saved, the nail one way being of the same breadth or thickness from head to point.'* Since the year 1820, the following patents have been obtained in England for making nails ; many of them of American origin : — Alexander Law, September, 1821, for nails and bolts for ships' fastenings, made in a twisted form, by hand labor. Glascott and Mitchell, December, 1823, for ship nails with rounded heads, by hand labor. Wilks and Ecroyd, November, 1825, for an engine for cutting wedge-form pieces from plates. Ledsom and Jones, December II, 1827, for machinery for cutting brads and sprigs from plates ; it does not form heads. The first nail apparatus to which I shall particularly advert, is due to Dr. Church ; it was patented in his absence by his correspondent, Mr. Thomas Tvndall, of Birmingham in December, 1827. It consists of two parts; the first is a mode of forming nails, and the shafts of screws, by pinching or pressing ignited rods of iron between indented rol- lers ; the second produces the threads on the shafts of the screws previously pressed. The metallic rods, by being passed between a pair of rollers, are rudely shaped, and then cut asunder between a pair of shears ; after which they are pointed and headed, or other- wise brought to their finished forms, by the agency of dies placed in a revolving cylinder. The several parts of the mechanism are worked by toothed wheels, cams, and ' levers* The second part of Dr. Church's invention consists of a mechanism for cutting the threads of screws to any degree of obliquity or fonn.* Mr. L. W. Wright's (American) apparatus should have been mentioned before the pre- ceding, as the patent for it was sealed in March of the same year ; though an amended patent was obtained in September, 1828. Its object was to form metal screws for wood. I have seen the machinery, but consider it much too complex to be described in the present work. Mr. Edward Hancorne, of Skinner street, London, nail manufacturer, obtained a patent in October, 1828, for a nail making-machine, of which a brief description may give my readers a conception of this kind of manufacture. Its principles are simiUir to those of Dr. Church's more eleborate apparatus. The rods or bars having been prepared in the usual way, either by rolling or hammer- ing, or by cutting from sheets or plates of iron, called slitting, are then to be made red- hot, and in that state passed through the following machine, whereby they are at once cut into suitable lengths, pressed into wedge forms for pointing at the one end, and stami>ed at the other end to produce the head. A longitudinal view of the machine is shown in tig. 991. A strong iron frame-work, of which one side is shown at a a, supports the whole of the mechanism. 6 is a table capable of sliding to and fro horizontally. Upon this table are the clamps, which lay hold of the sides X)f the rod as it advances- as also the shears which cut the rod into nail lengths auvances, These clamps or holders consist of a fixed piece and a movable piece • the latter be- in^ brought into action by a lever. The rod o."bar of iron shown at I having been madt rel hot. IS introduced into he machine by sliding it forward upon the tabled whenthe table IS m its most advanced position ; rotatory motion is then given to the crank shaft^ ♦ For further details, see Newton's Journal, 2nd series, vol liL p. 184 S5i NAILS. by means of a band passing round the rigger pulley «, which causes the table 6 to be drawn back by the crank rod /; and as the table recedes, the horizontal lever is acted upon, which closes the clamps. By these means the clamps take fast hold of the sides of the heated rod, and draw it forward, when the moveable chap of the shears, also acted upon by a lever, slides laterally, and cuts off the end of the rod held by the clamps : the piece thus separated is destined to form one nail. Suppose that the nail placed at g, having been thus brought into ihe machine and cut off, is held between clamps, which press it sideways (these clamps are not visible in this view) ; in this state it is ready to be headed and pointed. The header is a steel die /», which is to be pressed up against the end of the nail by a cam t, upon the crank-shafl ; which cam, at this period of the operation, acts against the end of a rod fr, forming a continuation of the die A, and forces up the die, thus compress- ing the metal into the shape of a nail-head. The pointing is performed by two rolling snail pieces or spirals /, /. These pieces arc somewhat broader than the breadth of the nail ; they turn upon axles in the side frames. As the table b advances, the racks wi, on the edge of this table, take mto the toothed segments «, «, upon the axles of the spirals, and cause them to turn round. These spirals pinch the nail at first close under its head with very little force ; but as they turn round, the longer radius of the spiral comes into operation upon the nail, so as to press its substance verv strongly, and squeeze it into a wedge form. Thus the nail is completed, and is immediately discharged from the clamps or holders. The carriage is then again put in motion by the rotation of the crank-shafY, which brings another portion of the rod c forward, cuts it off, and then forms it into a nail. Richard Prossery July, 1831, for makins: tacks for ornameatal furniture, by soldering or wedging the spike into the head. This also is the invention of Dr. Church. Dr. William Church, Februan', 1^32, for improvements in machinery for making nails. These consist, first, in apparatus for forming rods, bars, or plates of iron, or other metals; secondly, in apparatus for converting the rods, &c., into nails; thirdly, in im- provements upon Prosser's patent. The machinery consists in laminating rollers, and compressinar dies. . , • i . The method of forming the rods from which the nails are to be made, is very advanto- geous. It consists in passing the bar or plate iron through pressing rollers, which have indentations upon the peripheries of one or both of them, so as to form the bar or plate into the required shape for the rods, which may be afXerwards separated into rods of any desired breadth, bv common slittine rollers. The principal object of rolling the rods into these wedge forms, is to measure out a quantity of metal duly proportioned to the requir^'d thickness or strength of the nail m its several parts ; which quantity corresponds to the indentations of the rollers. Thomas John F^'ller, February 27, J 834, for an improved apparatus for making square- pointed and also flat-pointed nails. He claims as his invention, the application of ver- tical and horizontal hammers (mounted in his machine) combined for the i)urpo8e of tapeiing and forming the points of the nails ; which, being made to act alternately, re- semble hand work, and are therefore not so apt to injure the fibrous texture of the iron, he imagines, as the rolling machinery is. He finishes the points by rollers. Miles Berry y February 19, 1834, for machinery for forming metal into bolts, rivets, nails, and other articles ; beinsr a communication from a foreigner residing abroad. He employs in his machine holding chaps, heading dies, toggle joints, cams, &c., mechan. isms apparently skilfully contrived, but too complex for admission under the article naU in this volume. ^ . . , • .i r a • William Southwood Stacker, Julv, 1836. This is a machine apparently of American parentage, as it has the same set of features as the old American mechanisms of Perkins and Dyer, at the Britannia Nail-works, Birmingham, and all the other American machines since described, for pressing metal into the forms of nails, pins, screw-shaf\s, rivets, &c. ; for example, it possesses pressers or hammers for squeezing the rods of metal, and form- in*' the shanks, which are all worked by a rotatory action ; cutters for separating the ap- propriate lengths, and dies for forming the heads by compression, also actuated by revolv- ing cams or cranks. *. . . Mr. Stocker intends, in fact, to effect the sar..e sorts of operations by automatic me- chanisms as are usually performed by the hands of a nail-maker with his hammer and anvil ; viz., the shaping of a nail from a heated rod of iron, cutting it oflfat the proper length, and then compressing the end of the metal into the form of the head. His machine may be said to consist of two parts, connected in the same frame ; the one for shaping the shank of the nail, the other for cutting it off and heading it. The frame consists of a strong table to bear the machinery. Two pairs of hammers, formed as levers, the one pair made to approach each other by horizontal movements, the other pair by vertical move- ments are the implements by which a portion at the end of a redhot rod of iron is beaten or pressed into the wedge-like shape of the shaft of a nail. This having been NANKIN. S6ff done, and the rod being still hot, is withdrawn from the beaters, and placed in the other part of the machine, consisting of a p*ir of jaws like those of a vice, which pinch the shank of the nail and hold it fast. A cutter upon the side of a wheel now comes round, and, bv acting as the moving chap of a pair of shears, cuts the nail oflT from the rod. The nail shank being stUl firmly held in the jaws of the vice, with a portion of its end projecting outwardly, the heading die is slidden laterally until it comes opposite to the end of the nail ; the die is then projected forward with great force, for the purpose of what is termed upsetting the metal at the projecting end of the nail, and thereby blocking out the head. A main shaft, driven by a band and rigger as usual, brings, as it revolves, a cam into operation upon a lever which carries a double inclined plane or wedge in its front or acting part. This wedge being by the rotatory cam projected forwards between the tails of one of the pairs of hammers, causes the faces of these hammers to approach each oth«r, and to beat or press the redhot iron introduced between them, so as to flatten it upon two opposite sides. The rotatory cam passing round, the wedge lever is relieved, when springs instantly throw back the hammers ; another cam and wedge-lever now brings the second pair of hammers to act upon the other two sides of the nail in a similar way. This is repeated several times, until the end of the redhot iron rod, gradually advanced by the hands of the workman, has assumed the desired form, that is, has received the bevd and point of the intended nail. The rod is then withdrawn from between the hammers, and m its heated state is 16- troduced between the jaws of the holders, for cutting oflf and finishing the nail. A bevel pinion upon the end of the main shafl, takes into and drives a wheel upon a transverse shafl, which carries a cam that works the lever of the holding jaws. The end of the rod being so held in the jaws or vice, a cutter at the side of a wheel upon the transverse shaft seplirates, as it revolves, the nail from the end of the rod, leaving the nail firmly held by the jaws. By means of a cam, the heading die is now slidden laterally opposite to the end of the nail in the holding jaws, and by another cam, upon the main shaft, the die is forced forward, which compresses the end of the nail, and spreads out the nail into the form of a head. As the main shafl continues to revolve, the cams pass away, and allow the spring to throw the jaws of the vice open, when the nails fall out; but to guard against the chance of a nail sticking in the jaws, a picker is provided, which pushes the nail out as soon as it is finished. In order to produce round shafts, as for screw blanks, bolts, or rivets, the faces of the hammers, and the dies for heading, must be made with suitable concavities. NAILS. {Exhibition.) John Reynolds, Crown Nail Works, Newton Row, Birming- ham, Manufacturer. _ ^ . . A case enclosing a card of cut nails, consisting of upwards of 200 distinct varieties of the most useful strengths and sizes, made of iron, zinc, brass, and copper. In this manufacture sheets of iron of the proper thickness are cut across by a pair of cutting edges, which are set in motion by machinery ; the breadth of these strips is equivalent to the length of the nails to be produced from them ; the strip, for the conve- nience of turning, is fastened into apairof grips attached to a wood shank, resting when in use upon a support immediately behind the workman. The nail machine consists essentially of a pair of cutting chisels or edge?, which work perpendicularly, parallel to each otlier ; a gauge, to determine the breadth of a nail ; a pair of grips, into which at the time the wedge of iron fails, and where it is firmly held until the small horizontal hammer strikes it and produces the head, when it is dropped into a box beneath. Brads are not headed, but are simply cut out of each other ; that is to say, a deficiency in the Earallelism of the cutting edge produces the head and prepares for the head of the next rad to be cut therefrom. Glaziers' brads being simple wedge-like pieces of iron, with- out any head whatever, are produced by the simple operations of the chisels or cutters. When tucks are blued they are done in quantities by exposing them to heat in an oven or muffle, or upon an iron plate. Japanning is performed by the ordinary process. NANKIN, is a peculiarly colored cot'.on clotli, originally manufactured in the above named ancient capital of China, from a native cotton of a brown yellow hue. Nan kin cloth has been long imitated in perfection by our own manufacturers; and is now exported in considerable quantities from England to Canton. The following is the process for dyeing calico a nankin color. ' 1. Take 300 pounds of cotton yarn in hanks, being the qnantity which four workmen can dye in a day. The yarn for the warp may be about No. 27'8, and that for the weft 23'8 or 24r's. 2. For alwixing that quantity, take 10 pounds of saturated alum, free from iron (see Mordant); divide this into two portions; dissolve the first by itself in hot water, so as to form a solution, of spec. grav. 1° Baume^. The second portion is to be reserved for the galling bath. 8. Galling, is given with about 80 pounds of oak bark finely ground- This bark may serve for two quantities, if it be applied a little longer the second time. 266 NAPHTHA. 4. Take 30 pounds of fresh slaked quicklime, and form with it a large bath of lime- water. 5. Nitro-muriate of tin. For the last bath, 10 or 12 pounds of solution of tin are used, which is prepared as follows : Take 10 pounds of strong nitric acid, and dilute with pure water till its specific gravity be 26° B. Dissolve in it 4633 grains ( 10| oz. avoird.) of sal ammoniac, and 3 oz. of nitre. Into this solvent, contained in a bottle set in cold water, introduce successively, in very small portions, 28 ounces of grain-tin granulated. This solution, when made, must be kept in a well stoppered bottle. Three coppers are required, one round, about five feet in diameter, and 32 inches deep, for scouring the cotton ; 2. two rectangular coppers tinned inside, each 5 feet long and 20 inches deep. Two boxes or cisterns of while wood are to be provided, the one for the lime-water balh, and the other for the solution of tin, each about 7 feet long, 32 inches wide, and 14 inches deep ; they are set upon a platform 28 inches high. In the middle between these two chests, a plank is fixed, mounted with twenty-two pegs for wringing Ihe hanks upon, as they are taken out of the bath. 6. Muming. After the cotton yarn has been scoured with water, in the round copper, oy being boiled in successive portions of 100 pounds, it must be winced in one of the square tinned coppers, containing two pounds of alum dissolved in 96 gallons of water, at a temperature of 165° F. It is to be then drained over the copper, exposed for some time upon the grass, rinsed in clear water, and wrung. 7. The galling. Having filled four-fifths of the second square copper with water, 40 pounds of ground oak bark are to be introduced, tied up in a bag of open canvass, and boiled for two hours. The bag being withdrawn, the cotton yarn is to be winced through the boiling tan bath for a quarter of an hour. While the yarn is set to drain above the bath, 28 ounces of alum are to be dissolved in it, and the yarn being once more winced through it for a quarter of an hour, is then taken out, drained, wrung, and exposed to the air. It has now acquired a deep but rather dull yellowish color, and is ready without washing for the next process. Bablah may be substituted for oak bark with advantage. 8. The liming. Into the cistern filled with fresh made lime-water, the hanks of cotton yarn, suspended upon a series of wooden rods, are to be dipped freely three times in rapid succession ; then each hank is to be separately moved by hand through the lime bath, till the desired carmelite shade appear. A weak soda ley may be used instead of lime water. 9. The brightening is given by passing the above hanks, after squeezing, rinsing, and airing them, through a dilute bath of solution of tin. The color thus produced is said to resemble perfectly the nankin of China. Another kind of nankin color is given by oxyde of iron, precipitated upon the fibre of the cloth, from a solution of the sulphate, by a solution of soda. See Calico- NAPHTHA, or ROCK-OIL {Huile petrole, Fr. ; Sieindl, Germ.) ; the Seneca oil of Korth America, is an ethereous or volatile oil, which is generated within the crust of the earth, and issues in many different localities. The colorless kind, called naphtha, occurs at Baku, near the Caspian Sea, where the vapors which it exhales are kindled, and the flame is applied to domestic and other economical purposes. Wells are alsp dug in that neighborhood, in which the naphtha is collected. Similar petroleum wel» exist in the territory of the Birmans, at Yananghoung, upon the river Irawaddy, 80 hours' journey north-east of Pegu, where no less than 220 such springs issue from a pale blue clay, soaked with oil, which rests upon roofing slate. Under the slate is coal containing much pyrites. Each spring yields annually 173 casks of 950 pounds each. Petroleum is also found at Amiano in the duchy of Parma, at Saint Zibio in the grand duchy of Modena, at Neufchatel in Switzerland, at Clermont in France, upon some points of the banks of the Iser, at Gabian, a vill^e near Bezi^res, at Tegernsee in Ba- varia, at Val di Noto in Sicily, in Zante, Gallicia, Wallachia, Trinidad, Barbadoes, the United States, Rangoon, near Ava, strong ^«at ^^^^^^^^ ^^^ ^^^^ ^a* .ane'se is ^^'f^ly volatile. Alt^^^^^^^^^^ ,hods been raised too high, still it is possiDie xo ^f'*'^^ ' \ ,/ ,, - .i^ method of Barresvil S.e oxide of manganese, will be P'-'^'P' ^'''^ "' » "^"tt same manner as cob.lt, a. From nickel, the manganese may be ^^^t scpaiated n the «»"« J*^ howeverVby I have remarked above. Mansanese may be »«P»™*f'l f^^f'^^X j^^^^ „'p„i . method which, in its essential parts, was P^^P"'^"! '^Jj^^JJ^^^h oSns'by Xiii^^^d^lSir^ia^^rhrtw srfio%''^:rKrcS^ attention to th.s curious property and made us^^^^^^^^ ^P^^^ ^^^^ ^^.^^ acid reaction ; the sulphurets oi nickei aim c /^ , ^ hvdrochlor c acid, with water containing a I'^tle sulphuretted hyd.ogen and a tj^«^«* '^J .^ ^^^^^^^ The sulphuret of manganese is f «;, ^f.^ J^^^ /^^^^^^^^ drtV flesh-colored precipi- from the sulphurets of nickel and cobalt gives <>^ly^^^^^^^^^ ^^^ ^j^^ sulphuret of tate on the addition of ammonia ^^^^ ^jf ^«"JP^^^^^ there- manganese contains «™all Portions of sulphur^^^^^^^^ nicked a^ ^^^^^^ ^^ ^^^ forett is treated anew with very dilute .^^^J^^^;^^*^. ^''^ment a very nearly correct black sulphurets remain b«hmd By this repeated tre^^^^^^^^ manner,|ave 0-214 of^^-^-^tt^ntkef "and i: t^^tT frL cobalt, in the same Iron also may be «<'P»r***«,,\™" "'^f V*^ ufce sulphuret of manganese, is eas.Iv roSTi-irv^jehTdro^o^^^ "IccUcti/is malTJo tt .olution, especially if the latter oxides are present From alumina oxide of nickel may be separated by fusing them together with hydrate of potash in a silver crucible ; on treating the fused mass with water, the oxide of nickel remains behind in a dense state. It weighs nither more than the oxide emploved, but contains no alumina, and potash must therefore be present 0-238 gr. oxide of nickel mixed with alumina weighed, after it had been treated in this manner, 0*245 gr. By boiling with a solution of potash, nickel cannot be separated from alumina, when botk are contained in a solution, not even when the treatment is repeated. When the 0-246 gr. was dissolved in hydrochloric acid with the help of a little sulphuric acid, and the separated solution of alumina in potash, to which more potash was added, mixe*! witk the solution, and the whole boifed, the oxide of nickel separated weighed O" 320 gr. When this was dissolved in hydrochloric acid, a considerable quantity of alumina separated on the addition of ammonia in excess. As, however, the fusion of hydrate of potash in a silver crucible is attended with inconvenience, and the oxide of nickel obtained requires to be dissolved and precipitated anew, the separation of these oxides by means of carbonate of baryta is preferable. I have tried in vain, by fusing with a fixed alkaline carbonate, to separate quantita- tively alumina from the oxides of cobalt and nickel, and from those of other metals which are incapable of expelling the carbonic acid from an alkaline carbonate at aa elevated temperature. It is difficult to obtain a perfectly cl^r solution by fusing alu- mina with carbonated alkali, and treating the melted mass with water ; it is quickly rendered turbid by the carbonic acid of the atmosphere. A fused mass is much moi-e easily obtained with carbonate of soda than with carbonate of potash. Nickel and 6'o6a/^— Mingled with the beautiful samples of copper pyrites and argen- tiferous galena displayed in Class 1. of the Groat Exhibition, there were to be found several specimens of cobalt and nickel ores. These valuable articles lay buried beneath the huge bulk of their better known compeers, and, unless sought for, would fail to arrest the attention even of a scientific observer ; thus singularly illustrating in the Crystal Palace the obscure position they occupy in the manufacturing industry of the nation. The art of working the ores of cobalt and nickel seems unknown in Great Britain, if we may judge by the fact, that though found in sufficient abundance, they are nowhere in this country converted into zatfre and speiss, the two primary marketable producU elsewhere obtained from these ores. Although, therefore, no nation in the world con- sumes in Its manufactures more cobalt and nickel than Great Britain, yet for these metals it is entirely dependent upon Norwa}', Northern Germany and the Netherlands- from whence we import annually not less than 400 tons of zaffre and smalts, and ue.Hrly the same quantity of nickel and speis.^ to the conjoint value of about 150,00u/. sterling. £^ these substances serve very different purposes in the aits, we propose to speak of them separately,— merely premising that cobalt forms the bases of all the blue colors seen on earthenware, whilst nickel is an indispensable ingredient in the various metallic alloys, known under the terms albata, German silver, Ac. The specimens of ore previously alluded to as existing in the Great Exhibition have been derived from Cornwall, and contain, as is generally the case, both nickel and cobalt, thus far being precisely similar to the ores worked in Norway and Northern Germany. The foreign ores are, however, much richer than the Cornish, since these latter seldom contain more than'from 2 to 7 per cent, of available metallic matter, whilst the former not unfrequently yield 12 or 15 per cent. ; consequently, a process which answers quite well with the one may fail altogether, or prove profatless with the other; and this is exactly the whole secret of our national failuie in working cobalt ore. The Swedish method has been tried in several parts of Cornwall, and has not in any one instance given a satisfactory result • hence, the Crystal Palace contains no specimen of British zaffre, and our potteries, glass works, and paper manufacturers procure from abroad that which ignorance and apathy deny them at home. In the German ore the quantity of metallic ingredients is not only larger than in the Cornish, but also of a more fusible character ; consequently when simply subjected to heat in a reverberatory furnace, the earthy and metallic elements separate of themselves by the mere disparity of their specific weights ; and the silicious gangue, with a portion of oxide of iron, rises to the top; leaving a metallic compound of arsenic, cobalt nickel, copper, and perhaps iron beneath. This latter, when carefully roasted m an oxidizing furnace, in contact with sand or ground flint, aflFords at once an impare silicate of cobalt and arseniuret of nickel,—two marketable products. The llT'!f Tf ' ^v"^ ^^'"^ metallic poverty, will not undergo the first fusion necessary to Jn^K „ v! 1 «^^|f ^^«* "'^t"^ of the mineral ; and this triflhig impediment seems actuilly L inT *J^"".™^®*? *•;? «"^rgy of that indomitable spirit of enterprise for which Britaii rlnl ?K r^- J«««y ce ebrated. In the manufacture of iron, limestone is used to Inrfn kI !k ^°!J"'' ^'"'^ '''•'* ^^ ^^^ «^« f»«ibl« J ^^^ without this DO irou Can be pro. In n!;n^^. ordinary process. In roasting lead ore, lime cannot be dispensed with. inmmT /"* K ",?' ""^^^ T^^ ^'"^ ^"^ «^«^ fl^^i- «Pa^ is frequeiftly needed ; and the commonest cobalt ores of Cornwall clearly require nothing but a proper flui to aflford ^1 268 NICKEL. a compound of arsenic, cobalt and nickel, perfectly analogous to that procured from the German ore by mere fusion without a flux. The whole question, therefore, really resolves itself into the discovery of a cheap material capable of easy vitrification with the granitic matrix of the Cornwall ore, and which is nevertheless devoid of action upon the arseniuret of cobalt and nickel. The common fixed alkalis, though answer- ing the fiist indication admirably, would not comply with the second condition ; hence potash and soda, these great helpmates of industrial skill, are unfortunately excluded from the list of agents, as they act powerfully upon all the arseniurets, and would merely produce a worthless frit with the ore. Similar objections attach more or leee to the alkaline earths, and therefore lime requires to be looked upon with suspicion. Borax would and does yield a satisfactory result, but its high price is an insurmount^ able obstacle. Fluor spar is of no avail, and bottle glass requires too strong a tem- perature, and to be used in too great a quantity, for economical application to a mine- ral already suicharged with extraneous matters. These facts serve in some measure to explain, though we cannot in any way allow that they justify, the present condition of the zafFre market ; since these very difficulties are daily overcome in one of the largest metallurgical operations carried on amongst us. Many of the ores of copper, when fii-st received by the manufacturer, are in a state quite parallel to that of the Cornish ores of cobalt, even in regard to poverty of metaL There is the same excess of granitic matrix, the same necessity for avoiding the use of any agent capable of attacking sulphuret of copper, a substance possessing very similar chemical affinities to those of the arseniurets of nickel and cobalt What then is the flux employed by the copper manufacturer in such cases? We reply at once, — it is the protoxide of iron which is formed from these poor copper ores by the action of heat, and combines with the silicate of the matrix so as to produce an extremely fusible silicate of iron, which permits the sulphuret of copper to fall down to the lower part of the reverberatory furnace, whilst the vitrified impurities of the ore are raked from its surface. Oxide of iron would most probably therefore enable a manufacturer, accustomed to furnace operations, to send into the market an arsenical compound of cobalt containing more than 60 per cent, of this metal, even if his interest failed to convince him of the great advantage resulting from its subsequent conversion into zaffre. Thus, then, the conditions of this seemingly difficult problem are answered, in a commercial sense ; for oxide of iron is plentiful and cheap, its combination with silica is sufficiently fusible, and it has no action whatever upon metallic arseniurets. No doubt many other substances might be found equally applicable with the one we have mentioned; and, indeed, our object in thus dilating upon this and analogous topics is rather to stimulate inquiry than to lay down specific rules for practical guidance ; conse- quently our remarks must be regarded at best as but a shadowy outline, the manu- facturing details of which require careful filling in, to render the whole intelligible and useful. Before quiting the subject of cobalt, it may be as well to advert to a particular ore of that metal, found near Keswick in Cumberland. This ore contains from two to three per cent of cobalt, but is quite free from nickel, — a very unusual circumstance, — as even in meteoric stones cobalt iri constantly accompanied by nickel, though this last metal not unfrequently exists without cobalt As a coloring material, oxide of cobalt is seriously damaged by the presence of oxide of nickel, for these oxides produce colors almost complementary to each other ; and therefore tending, by their admixture,to yield a neutral tint, as is observable when their saline solutions are united. The great ad- vantage of working an ore of cobalt free from nickel must consequently be obvious to all. The Keswick mine is, nevertheless, almost abandoned at the present moment, through sheer inability to find a market for its produce ; though for tl.e finer kinds of porcelain and for enamel painting, the oxide of cobalt procured from it is worth fully a guinea per pound. In the hope of drawing attention to a raw material at once so unique and valuable, we give the following original process for extracting pure oxide of cobalt from the Keswick cobalt ore : — Having carefully roasted a quantity of this ore, at a full red heat, in a muffle furnace, for two or three hours, it is next to be reduced to a fine powder, and then digested in muriatic acid of the specific gravity 110 or thereabout And for this use the waste acid of the soda maker is well adapted, even though it may happen to contain arsenic and iron. After a few hours' digestion, the acidulous solution may be poured otf and a fresh acid added, so as completely to exhaust the roasted ore, and, dissolve all the metallic matter in it Then mix the solution thus procured : and having thown in a portio-n- of powdered htematitc or other form of peroxide of iron, evaporate the whole to dryness. Next pour boiling water on the dried mass, and stir in an excess of chalk, or finely powdered marble, and preserve the whole at a temperature of abou» 18<)° Fiihr, until all evolution of carbonic acid ceases; then add a quantity of suiphate of soda, and thiow the mixtuie on a filter, when asolutionof chlo- NITRATE OF AMMONIA. 269 nde of cobalt will pass' through, containing a small quantity of the sulphates of lime and soda, but altogether free from metallic contamination. This solution must now be super-saturated with a caustic lye of soda, and the mixture boiled for a few minute- in order to insure the rapid precipitation of the oxide of cobalt; which, after careful •washing with hot water, is to be dried, and heated red hot, in a crucible, to give it the character suitable for the English market One pound of Keswick ore will require about 8 ounces of muriatic acid, of the kind alluded to, with 2 ounces of haematite, 3 ounces of chalk, and the same quantity of salt cake or dry sulphate of soda. The ex- planation of this process is very simple: in the first instance, the metallic matters of the ore, consistmg of iron, cobalt arsenic, copper, and perhaps also lead, are dissolv- ed by the muriatic acid ; and, as all of these are precipitated by carbonate of lime, except cobalt, the chalk might now be added at once, but for the fact that the Kes- wick ore contains an excess of arsenic, which carries down a portion of cobalt in the state of arsenite of cobalt To remedy this evil, peroxide of iron or ha;matite must be added, so as to ensure the existence of an excess of peroxide of iron in the solution ; as this, on the introduction of the chalk, will unite to the arsenic, and thus prevent the precipitation of any cobalt at this stage of the operation. The cessation of all eflferves- cence, indicates tliat the chalk has ceased to act, and that the iron, arsenic, copper and lead are no longer in solution, but have been displaced by the lime of the chalk.' To remove this lime, 6uli)hate of soda is employed, since this throws down nearly the whole ot the hme in the state of sulphate; after which caustic soda or potash will precipitate nothing from the filtered solution but pure oxide of cobalt Although apparently somewhat complex in detail, this process is extremely simple and efficient in practice • and possesses, moreover, the advantage of being equally applicable to the treatment of speiss or arseniuret of nickel, from which pure oxide of nickel may be easily procured, —using, however, much more haematite than the quantity above indicated, in conse- quence of the absence of iron in speiss. From this latter circumstance, it must be ob- vious, that cobalt and nickel cannot be separated in the way just described; for, as has been stated, they both remain in solution after the employment of the chalk; and, in- deed, no process has yet been published by which a perfect separation of these two met- als can be effected. Ordinary Swedish zaffre contains, on an average, 15 per cent of oxide of cobalt mixed with about 3 per cent of oxide of nickel ; which latter seri- ously impairs the coloring power of zaffre. Hence it is that we have entered thus fully into this question; for as it is almost impossible to purify cobalt when contaminated with nickel. It 18 a kind of national disgrace to Great Britain that, having a pure ore ot cobalt in the very centre of the island, our manufactures are unable either to com- ** vTn^-rr JU'l-S"^^ *^ ^^°^^^^ ^^^* ^^® P^^^^ <^^ superiority in the formation of zaffre. JNlOOllANliSE, is the name of an oil recently extracted from the leaves of tobac- co, which possesses the smell of tobacco smoke. NICOTINE, is a peculiar principle, obtainable from the leaves and seeds of tobacco {ntcottana tabacufn), by infusing them in acidulous water, evaporating the infusion to a certain point, adding lime to it, distilling, and treating the product which comes over J^oVi * • ^^ colorless, has an acrimonious taste, a pungent smell, remains liquid at •f K m' ^^^l^^ »1^ proportions with water, but is in a great measure separable from It by ether, which dissolves it abundantly. It combines with acids, and forms salts acrid and pungent hke itself; the phosphate, oxalate, and tartrate being crystallizable. Nicotine causes the pupils to contract A single drop of it is sufficient to kill a dog. Macerate powdered tobacco for twenty-four hours in water acidulated with sulphu- ?1 w^h! ^^''P^^^ ^\^ l^q»o>-. evaporate to the consistence of syrup, and distil the resi- ?»U ! sufficient quantity of potash ; add more water from time to time to prevent centraLd^TrZfK- ^^a- ^j^^^"^ ^^ consequence of the potash being too much con- Tin fhr...-''"' this distillation a Quantity of nicotina and ammonia will be obtain- f« TJutl JT' ^''^i ^^'''•'^ *^^ *^ ^« neutralized with oxalic acid. Evaporate now nf nSma Z '''^'i^' ""^^^"^ ^^^^ boiling alcohol, which will dissolve the oxalat^ tLT sXt o'^of'^no?' r ^^'^ "^ """^"'^^'^ "°^^^^^ "P«°- H^^t '^' o--J-t« of nil ble and from whL^^^^ separate the nicotina with ether, in which it is solu- M ArH^To • Z^^^^^'^^^^y *S*^" ^e separated by distillation, of wa^te?rd^7"atoLV''^ "^^^^^^ ^^^ *^ be "perfectly^re. but to contain a porUon rid^eT^f Ikt^nuifand ^^ '"^' ^Z^'^ ^^ '^' combination of nicotina with the chlo- r4rM?S;;^ -P-nted the composition of this Cio = 73-26 Hs = 9-65 NITRATE OF AMMONIA, i, p«'p;.r7d "by" neutralizing nitric acid with ««. 270 NITRATE OF POTASH. feiing^g^™''"''* """^ crystallizing the solution. Heat converts it into water and nitrate' OF LEAD {Nitrate de plomb, Fr. ; Salpetersaures hleioxvd GernLV is made by saturating somewhat dilute nitric acid^ith o'Lide oHeld htharie Wo;at- ng the neutral solution t.U a pellicle appears, and then exposing it in aTotch^^^^^^^ till It be converted mto crystals, which are sometimes transparent, but generallvopaaue white octahedrons The.r spec. grav. is 4068 ; they have a coolinrs^weeUsh Vu^^^^^^^^^ taste. They dissolve in 7 parts of cold, and in much less boiling wLtertheV^u^e^^^^^^ moderate elevation of temperature, emit oxygen ^as, and pas^slntr'oide of lead Their constituents are 67-3 oxide and 327 aciX NTtrate of lead is mLnmployed in the chrome yellow style of Calico printing ; which see employ ea in There are three other compounds of nitric acid and lead oxide- viz. the bi-basic 1 oVadd""' "^ ''' ''•^^"' "^'^^ ^^"^^" respectively 2%"nd'6 atoms of i^^^^^^ ili™^J? TMs'^^'lf ""' ""'''% "''^^^"- J^*'^^'^ ^ ^^'--' F- ' Salpetersaure. maris Si L^ . w T^^'f ?**'^^ ^ ^? efflorescence upon limestones, sandstones. ZI nf fhi ' j^^l^*"^!^; l\ f«^ms a salme crust in caverns, as also upon the s,?- decomDosed ^Cw "^ "'''"•". P' r'^ "'P^^'""^ ^^^^« *'"">«! "^«"«- ^^^^e been decomposed Such caverns exist in Germany near Homburg (Burkardush) • in Aoulia XI ?9 ^f^''^' '"" ^^"^" ^' ^^"^^"*)' ^^ ^-^"^^J i"^ t^e East Ind's 'in Ce??on! where 22 nitriferous caverns a.-e mentioned ; in JVorth America, at Crooked rW l^lnTZ'^ m"^^^' *^^ ^P^" '\l ^^^^^^"""' ^° ^^^^^'' Teneriff; and AfricT S occurs as an efflorescence upon the ground in Arragon. Hungary. Podolia. Sicily ^a?ts\!S f tr/' ^^^^«V^T^r' 1^^^^'^ America.%nd Sou?h ^mencr Se veS plants contain saltpetre ; particularly borage, dill, tobacco, sunflowers, stalks of maizt Btences ^^ "" Parietaria, &c. It has not hitherto been found in anima"su£ «nJfo^ question has been frequently put; how is nitre annually reproduced upon the surface of limestones and the ground, after it has been removed b/washingf T h*^ the ox?le„'"nr/h ^' that as secondary limestones contain remains^of anim!l ma te^ bine w if their n.nrlT'?*'"'"' f '°'^'^, ^" r''""^ ^f '^^ I^«^«"^ ^^^"^t"^^» ^'^^ com! TZI' * • .u ^"^ ^""""J "'^""^ ^*''*'5 ^^'^"^^ "^trate of lime will resu t. Where potash IS present m the ground, a nitrate of that base wijl be next formed. The generation Sn fl rtV '" !!" T^u ^"^'^^ '^ * ^"^y '"^^" ^^^^«^^^ ^^«"^ ^he surface of porous stones^ no further, indeed, than where atmospherical air and moisture can penetr^e: and none IS ever produced upon the surface of compact stones, such as marble and quartz or Sf argillaceous minerals. Dr. John Davy and M. Longchamp have advanced an opinion that the presence of azotized matter is not necessary for the generation of nitric add or' Ta r w"^ ''' ^"i"'"' ''' "f ^^" ^"^.^^"^^ "^^^'^ atmosphere: when condensed bjcapS. laritj, will combine m such proportions as to form nitric acid, through the agencv of moisture and of neutralizing bases, such as lime, magnesia, potash, or soda^ They conceive 2^lTr""r ^^^''""^ .^^'^^^ '? combine oxygen and hydrogen into water, or the v^Tor of alcoho and oxygen into acetic acid, and as the peroxydeas wdl as the h drate of frSn and argillaceous minerals, serve to generate ammonia from the oxygen of the air and the hydrogen of water; in like manner, porous limestones, Ihrough^Oie agency^^^^^^^^^ operate upon the constituents of the atmosphere to produce nitric acid, without thrpreS ence of animal matter. This opinion may certainly be maintained; for in India,lpafn and several other countries at a distance from all habitations, unmeise quantUies of ^u! petre are reproduced in soils which have been washed the year before. BuronTe other hand, it is known that the production of this salt may be greatly facilitated an d in! creased by the admixture ot animal oflals with calcareous earths '^*^"^^^^^^ ^^'^ "»' The spontaneous generation of nitre in Spain, E^ypt, and espedallv in India i^ ^nffi aent to supply the wants of the whole world. TherVthis salt ToSved to fo'rm up^' the surface of the ground in silky tufts, or even in slender prismatic crystairpart^n. larly during the continuance of the hot weather that succeeds copious rains These saUne efl^orescences, after being collected by rude besoms of broomf are lixwited allowed to settle evaporated, and crystallized. In France, Germany, Sweden, Hunlrry&cvaS quantities of nitrous salts are obtained by artificial arrangements cXtFj/rt^W^^r ni re-beds Very little nitrate of potash, indeed, is obtain^ in the fim pkce bn 'the a rriiauid"4t;' Tr^'"' which bdng deliquescent, remain in the niSous eartis in a semi-liquid state. The operation of converting these salts into good nitre is often suf- to ehmfnate"!'' ^""^ "" consequence of the presence of several muriaL, wiichre di^c^t ^yll*/!/''"^'"^ instructions ha.e been given by the consulting committee of poudres et mlpetres m France, for the construction of thdr m7n>r« artificielle.. The perCability of the materials to the atmospherical air, being found to be as indisDeB«;able as i^ 1.1 presence of a base to fix the nitric acid at \he in'stant of L7omatTon?thr^^^^ lasi'e NITRATE OF POTASH. 871 is to select a light friable earth, containing as much carbonate of lime or old mortar- rubbish as possible ; and to interstratify it with beds of dung, five or six inches thick, till a considerable heap be raised in the shape of a truncated pyramid, which should be placed under an open shed, and kept moist by watering it from time to time. When the whole appears to be decomposed into a kind of mould, it is to be spread under sheds in layers of from two to three feet thick; which are to be watered occasionally with Brine and the drainings of dunghills, taking care not to soak them too much, lest they should be rendered impermeable to the air, though they should be always damp enough to favor the absorption and mutual action of the atmospherical gases. Moist garden mould afi'ords an example of the physical condition most favorable to nitre-beds. The compost should be turned over, and well mixed with the spade once at least in every fortnight, and the sides of the shed should be partially closed ; for although air be essen- tial, wind is injurious, by carrying off the acid vapors, instead of allowing them to rest incumbent upon, and combine with, the bases. The chemical reaction is slow and •uccessive, and can be made effective only by keeping the agents and materials in a state of quiescence. The whole process lasts two years ; but since organic matters would yield in the lixiviation several soluble substances detrimental to the extraction of saltpetre, they must not be added during the operations of the latter six months • nor must any thing except clear water be used for watering during this period ; at the end of which the whole organic ingredients of the beds will be totally decomposed. Where dung is not sufficiently abundant for the above stratifications, a nitre-bed should be formed in a stable with friable earth, covered with a layer of litter ; after four months the litter is to be lifted off, the earth is to be turned over, then another layer of fresh earth, 8 or 9 inches thick*, is to be placed over it, and a layer of the old and fresh litter over all. At the end of other four months, this operation is to be repeated ; and in the course of a year the whole is ready to be transferred into the regular nitre-beds under a shed, as above described. Such are the laborious and disagreeable processes practised by the peasants of Sweden, each of whom is bound by law to have a nitre-bed, and to furnish a certain quantity of mire to the state every year. His nitriary commonly con- sists ol a small hut built of boards, with a bottom of rammed clay, covered by a wooden floor, upon which is spread a mixture of ordinarj- earth with calcareous sand or marl, and lixiviated wood-ashes. This mixture is watered with stable urine, and its surface is turned over once a week in summer, and once a fortnight in winter. In some countries, walls 2 or 3 feet thick, and 6 or 7 high, are raised with the nitrifying com- post, interspersed with weeds and branches of trees, in order at once to bind them together, and to favor the circulation of air. These walls are thatched with straw ; they are placed with one of their faces in the direction of the rains ; and must be moist- ened with water not rich in animal matter. One side of the walls is upright and smooth ; while the other is sloped or terraced, to favor the admission of humidity into their interior. The nitre eventually forms a copious efflorescence upon the smooth side, whence it may be easily scraped off. M. Longcharap, convinced that organic matters-are a useless expense, and not in the least essential to nitrification, proposes to establish nitre-beds where fuel and labor arc cheapest, as amidst forests, choosing as dry and low a piece of ground as possible, laying them out upon a square space of about 1000 feet in each side, in the middle of which the graduation-house may be built, and alongside of it sheds for the evaporation furnaces and K*Tn r ^P^'^/^ch of the four sides the nitrifying sheds are to be erected, 130 feet long by JO feet wide, where the lixiviation would be carried on, and whence the water wouW be conducted in gutters to the graduation-house. The sheds are to be closed at the tides by walls of pise, and covered with thatch. No substance is so favorable to nitrification as the natural stony concretion known under the name of lime-tuf. In Touraine, where It IS used as a building stone, the saltpetre makers re-establish the foundations of old nouses at their own expense, provided they are allowed to carry off the old tuf, which owes Its nitritying properties not only to its chemical nature, but to its texture, which bdns of a homogeneous porosity, permits elastic fluids and vapors to pass through it freely in all di- rections. With the rough blocks of such tuf, walls about 20 inches thick, and moderately high, are to be raised, upon the principles above prescribed ; in the absence of tuf, porous ^«h' Tholf^,'^"* "^u^ * ?^V"'« «^ ^'•^We soil, sand, and mortar-rubbish, chalk or rich marl. The walls ought to be kept moist. thl^'Z'i^^rVJu^^T^VA ri.**^ ^^^ indigenous saltpetre is obtained by lixiviating tinWpT" wh'^h old buildings, especially of those upon the ground-floor, and in sunk cellars; which are by law reserved for this purpose. The first obiec! of the TZtZlV^Tr^^'y^'^'T^'''.'^^ ""'^'^^^^ «^ ^^' '"^terials in nitrous salt's, to see if they be worth the trouble of working ; and this point he commonly determines merely by their saline, hitter and pungent taste, though he might readily have recourse to the far surer criteria of lixiviation and evaporation. He next pounds them coarsdy, and puis them mto large casks open at top, and covered with straw at bottom ; which are i I 272 NITRATE OF SILVER. placed in three successive levels. Water is poured into the casks till they are full, and after 12 hours' digestion it is run off, loaded with the salts, by a spigot near the bottom. A fresh quantity of water is then added, and drawn off after an interval of four hours j even a third and fourth lixiviation are had recourse to ; but these weak liquors arc reserved for lixiviating fresh rubbish. The contents of the casks upon the second and third lower levels are lixiviated with the liquors of the upper cask, till the leys indicate from 12 to 14 degrees of Baume's hydrometer. They are now fit for evaporating to a greater density, and of then receiving the dose of wood-ashes requisite to convert the materials of lime and magnesia into nitrate of potash, with the precipitation of the carbonates of magnesia and lime. The solution of nitre is evaporated in a copper pan, and as it boils, the scum which rises to the surface must be diligently skimmed off into a cistern alongside. Muriate of soda being hardly more soluble in boiling than in cold water, separates during the concentration of the nitre, and is progressively removed with cullender-shaped ladles. The fire is withdrawn whenever the liquor has acquired the density of 80° B. ; it is allowed to settle for a little while, and is then drawn off, by a lead syphon adjusted some way above the bottom, into iron vessels, to cool and crystallize. The crystals thus obtained are set to drain, then re-dissolved and re-crystallized. The further purification of nitre, is fully described under the article Gunpowder. The annual production of saltpetre in France, by the above-described processes, dui ing the wars of the Revolution, amounted to 2000 tons (2 millions of kilogrammes) of an ar- ticle fit for the manufacture of gunpowder; of which seven twentieths were furnished by the saltpetre works of Paris alone. Considerably upwards of six times that quantity of common and cubic nitre were imported into the United Kingdom, for home consumption, iuring the year ending January 5, 1838. Nitrate of potash crystallizes in six-sided prisms, with four narrow and two broad faces : the last being terminated by a dihedral summit, or two-sided acumination ; they are striated lengthwise, and have fissures in their long axis, which are apt to con- tain mother water. The spec, gravity of nitre, varies from 1'93 to 2*00. It possessei a cooling, bitterish-pungent taste, is void of smell, permanent in the air when pure, tuses at a heat of about 662, into an oily-looking liquid, and concretes upon cooling into a solid mass, with a coarsely radiating fracture. This has got the unmeaning names of sal-prunelle and mineral crystal. At a red heat, nitre gives out at first a great deal of pretty pure oxygen gas ; but afterwards nitrous acid fumes, while potash remains in the retort. It is soluble in 7 parts of water at 32° ; in about 3| at 60° F., in less than half a part at 194°, and in four tenths at 212°. It is very slightly soluble in spirit of wine, and not at all in absolute alcohol. It causes a powerful deflagration when thrown upon burning coals ; and when a mixture of it with sulphur is thrown into a red-hot crucible, a very vivid light is emitted. Its constituents are, 46-55 potash, and 53*45 nitric acid. Nitre is applied to many purposes: — 1. to the manufacture of gunpowder; 2. to that of sulphuric acid; 3. to that of nitric acid, though nitrate of soda or cubic nitre has lately superseded this use of it to a considerable extent ; 4. to that of flint-glass ; 5. it is used in medicine ; 6. for many chemical and pharmaceutical preparations ; 7. for procuring by deflagration with charcoal or cream of tartar, pure carbonate of potash, as also black and white fluxes ; 8. for mixing with salt in curing butcher meat ; 9. in some countries for sprinkling in solution upon grain, to preserve it from insects ; 10. for making fire- works. See FiRE-woRKS. Landings, Deliveries, and Stocks of Saltpetre. Landed. Tons. In December . 1851 415 1850 607 In 12 Months . 1851 7,764 1850 9,661 1849 9,997 1848 11,034 Delivered. Stock 1st January. Tons. Tons. 551 — 671 — . 7,869 2,321 10,327 2,416 8,774 8,082 9,864 1,794 Prices. — Bengal, 25«. to 28«. 6ct per cwt. ; Madras, 24«. to 25«. NITRATE OF SILVER {Nitrate d'ar^ent, Fr. ; Silbersalpeter, Germ.); is pre- pared by saturating pure nitric acid of specific grav. 1*25 with pure silver, evapoi-ating the solution, and crystullizing the nitrate. When the drained crystals are fused in a f>latina capsule, and cast into slender cylinders in silver moulds, they constitute the unar caustic of the surgeon. This should be white, and unchangeable by light It is daliquescent in moist air. The crystals are colorless transparent 4 and 6 sided tables ; NITRATE OF SODA. 273 they possess a bitter, acrid, and most disagreeable metallic taste ; they dissolve in their own weight of cold, and in much less of hot water; are soluble in four parts of boiling Ulcohol, but not in nitric acid ; they deflagrate on redhot coals, like all the nitrates ; and detonate with phosphorus when the two are struck together upon an anvil. They consist of 68-2 of oxyde, and 3 1-8 of acid. Nitrate of silver, when swallowed, is a very energetic poison ; but it may be readily counteracted, by the administration of a dose of sea^salt, which converts the corrosive nitrate into the inert chloride of silver. Animal matter, immersed in a weak solution of neutral nitrate of silver, will keep unchanged for any length of time ; and so will polished iron or steel. Nitrate of silver is such a delicate reagent of hydrochloric or muriatic acid, as to show by a sensible cloud, the presence of one 113 millionth part of it, or one 7 millionth part of sea-salt m distilled water. It is much used under the name of indelible ink for writing upon linen with a pen ; for which purpose one drachm of the fused salt should be dissolved m three quarters of an ounce of water, adding to the solution as much water ot ammonia as will re-dissolve the precipitated oxyde, with sap-sreen to color it and gum-water to make the volume amount to one ounce. Traces written with this liquid should be first heated before a fire to expel the excess of ammonia, and then exposed to the sun-beam to blacken. Another mode of using nitrate of silver as an indelible ink 18 to imbue the linen first with solution of carbonate of soda, to diy the spot and write upon it with a solution of nitrate of silver, thickened with gum, and tinted' with sai>- green. *^ ^NITRATE OF SODA, Cubical Nitre (Nitrate de sonde, Fr. ; Wurfehalpettr, Germ.), occurs under the nitre upon the lands in Spain, India, Chile, and remarkably m Peru, in the districts of Atacama and Taracapa, where it forms a bed several feet thick. It appears m several places upon the surface, and extends over a space of more than 40 leagues, approaching near to the frontiers of Chile. It is sometimes efflo- rescent, sometimes crystallized, but oftener confusedly mixed with clay and sand. This immensely valuable deposite is only three days' journey from the port of Con- ception in Chile, and from Iquiqui, another harbor situated in the southern part of .^^\^- ""^ ^l^"" T^- ^^ artificially prepared by neutralizing nitric acid with soda, and crystallizing the solution. It crystallizes in rhomboids, has a cooling, pungent, bitterish iJLl"; ?«rjJ'p^'''f^'!^" f'*'^' »i,^e<^o°^es moist in the air; dissolves in 3 parts of water at 60° F., m less than 1 part of boiling water; deflagrates more slowly than nitre, and with an orange yellow flame. It consists, in its dry state of 36 6 soda and 63-4 nitric acid; but its crystals contain one prime equivalent of water; hence they are composed o^ acid 66-84, base 33-68, water 9-47. It is susceptible of the same applications as nitre, with the exception of making gun- ^w ^^^ ^^^*^^ i* ^8 not adapted, on account of its deliquescent property. We extract the following from a paper read before the Royal Geoi^raphical Society of London, on the 28th of April, 1851, entitled Observations on the Geography of Southern Peru, oria that of the latter ; there are in all about 100 officinos. The nitrate deposits com- mence aboutTilineche, and extend south neartoQuiUiagua with interruptions of deposit* of common salt. The nitrate caleche grounds vary in breadth ; the average mky be 500 yards, and in places 7 to 8 feet thick, and sometimes quite pure. In the ravines and hollows before mentioned, the nitrate is found on their shelving sides; the hol- lows look like dried-up cakes, and are covered with salt 2 to 3 feet thick, and on the margins there is nitrate of soda, ofttimes going down to some depth ; in others there is a hard dry crust upon it, occasionally 4 feet thick. The nitrate caleche formed under this lo 274 NITRATE OF STRONTIA. NITRIC ACID. 276 n I i i t erust 18 in thin layers, and so solid and pure as to be songht for, alUiough the eipenao "'"m^e^ire'iTefrvarieties of the nitrate of soda caleche, the following being th. principal. . . . * "1. White, compact, containing 64 per cent. " 2. Yellow, occasioned by salts of iodine, 70 per cent " 3 Gray compact, containing a little iron and a trace of iodine, 46 per cent. . «4 Giay crystall^e, the molt abundant variety, contains from 20 to 85 per cent, affording traces of iodine, with 1 to 8 per cent of earthy matter. "6. White crystalline: this resembles the refined nitrate. rr^^ o«^ " All these contain common salt, sulphate and carbonate of soda, munate oflime and occafionallv some borate oflime, as found under the nitrate beds: one variety of the UtCcompoBed of boracic acid 49-6, soda 8;8, water 26-0, lime 15-7=100, may probably become of use in this country in glass-making, (fee. .. ^ i. ^ .i • „ „«. "Fragment of shells have been noticed with and under the nitrate bed : this may ac- count income measure for the lime in the borate and munate. Mr ^ ^^ke -n -^^^^^^^^ 200 feet above the Pampa (which is 3500 above the level of the sea), near to Los »aietre» del fortr' limestone containing shells rises from a bed consisting of pebbles and she b cemenled togXr by salt and nitrate of soda ; part of the shells are decomposed, whibt Xrfare pS in^form, and like those now still found lying on the rocks m the in ^'''xLfr'ough nitrate of soda is broken int.> «°^f . Pi««f ^P^t ^^JJ^/l^^^' Tb! mlu^ duced and the whole boiled; the nitrate is held in solution, while the earthy matter; ill pCphat:^ separated and fall to the bottom of the v«^!« ' ^^^ -^"-^;^^ solution of nitrate is let into a reservoir, where it deposits any /:«°^*^^^"g ^^^^^^Xn ter; the clear liquor is run into shallow troughs. «?^P^««d t,<>.t^« «^°' ^ *in^^^^^^^ tak^s place, containing only 2 to 3 per cent of impurities ^^^'J^'^^yJ^'-Z^^'^^l^^^ S the^coasi for exportation. The Pampa de Tamaruagal contains ^^^^^.^^^^.^.^M^^^ Boda for the consumption of Europe for ages; the desert of Atacamo yields it, rt na» also been met with on the Andes and in the Eastern plains. "Imports into the United Kingdom from Chili and Peru of Cubic Nitre. compUed from Official Sources. Tears. ChUL Peru. Tons. Tons. 1832 296 498 1833 440 583 1834 2,521 1,303 1835 1,826 2,068 1836 2,183 1,625 1837 1,356 4,845 1838 1,091 2,099 1839 1,488 2,132 1840 2,651 4,696 1841 1,188 3,546 1842 6,048 4,239 1843 6,011 1,797 1844 1,523 5,531 1845 1,487 6,705 1846 2,669 6,752 1847 1,834 13,506 1848 1,676 8,425 1849 4,154 8,876 1850 1,150 10,740 NITRATE OF STRONTIA. {Nitrate de Strmtiane, Ft. ; Salpetersavrer stroniim. Germ ) This salt is usually prepared from the sulphuret of strontium, obtained by de- composing sulphate of stronlia with charcoal, by strong ignition of the mixed powders in a wucible. This sulphuret being treated with water, and the solution being filtered, is to be neutralized with nitric acid, as indicated by the lest of turmeric paper ; care being token to avoid breathing the noxious sulphureted hydrogen gas, which is copiously disen- ^ed The neutral nitrate being properly evaporated and set aside, affords colorless, Uansparent, slender octahedral crystals. It has a cooling, yet somewhat acrid taste; is «,luble in 5 parts of cold, and in one half part of boiling water, as also in alcohol i is permanent m the air, deflagrates upon bumin? coals, gives ofl^ oxygen when calcined and leaves caustic stronlia. The sail consists of 48-9 stronlia and 5M nitric acid. That salt is anhydrous ; but there is another variety of it, which contains nearly 40 per cent of water of crystallization, which occurs in large octahedrons. This is preferred for fire- works, because by efflorescence it is easily obtained in a fine powder, which mixes more intimately with the chlorate of potash and charcoal, for the composition of the brilliant red hres, now so much admired in theatrical conflagrations. NITRIC ACID, Aquafortis (Acide nitrique, Fr. f Salpetersaiire, Germ.), exists, m com- bination with the bases, potash, soda, lime, magnesia, in both the mineral and vegetable kmgdoms. This acid is never found insulated. It was distilled from saltpetre so lone ^o as the 13th century, by igniting that salt, mixed with copperas or clay, in a retort Witric acid is generated when a mixture of oxygen and nitrogen eases, confined over water or an alkaline solution, has a series of electrical explosions passed through it In this way the salubrious atmosphere may be converted into corrosive aquafortis When a little hydrogen is introduced into the mixed gases, standing over water the chemical agency of the electricity becomes more intense, and the acid is more rapidly fonned from Its elements, with the production of some nitrate of ammonia. Nitric acid is usually made on the small scale by distilling, with the heat of a sand bath, a mixture of 3 parts of pure nitre, and 2 parts of strong sulphuric acid in a laree glass retort, connected by a long glass tube with a globular receiver surrounded by cold water. By a well-regulated distillation, a pure acid, of specific gravity 1-500 may be thus obtained, amounting in weight to about two thirds of the nitre employed To obtain easily the whole nitric acid, equal weights of nitre and concentrated sulphuric acid may be taken ; in which case but a moderate heat need be applied to the retort The residuum will be bisulphate of potash. When only the single equivalent proporl tion of sulphuric acid is used, namely, 48 parts for 100 of nitre, a much higher heat is required to complete the distillation, whereby more or less of the nitric acid is decomnosed while a compact neutral sulphate of potash is left in the retort, very difficult to remove by solution in water, and therefore apt to destroy the vessel. Aquafortis is manufactured upon the great scale in iron pots or cylinders of the same construction as I have described under muriatic acid. The more concentrated the sul- Fn thT.f r' %^^'' corrosively will it act upon the metal ; and it is commonly used W I P'^T Z*'" ^^.u''^?? u ^^ "^.^'^^} ^"^ *^° ^^ "^^'■^- The salt being introduced into the cool retort, and the lid being luted tight, the acid is to be slowly mured in through the aperture /, Jig. 748 ; while the aperture g is connected by a long ^lasf tube wUh a range of balloons inserted into each other, and laid upon a sloping bed of sand. The bottle t, with 3 tubulures partly filled with water, which is required for condensing muriatic acid gas, must, for the present purpose, be replaced by a series of empty receiv- ers, either of glass or salt-glazed stoneware. The cylinders should be only half fiUed. and be worked off by a gradually raised heat. ^ .rScTT'*^ •^^^^v^ '^ T^v^ generally contaminated with sulphuric and muriatic rri^ilv L. "". ""''h ^i^'^''"^ '^^^?^*^? ^"^ "^""^^"^- '^^^ ^"^"t'ty of these salts may be wh,t^th«r nf r ^' f7^P«^^^t,ng m a glass capsule a given weight of the aquafortis ; r.^i K •» /^'^T'"'^^**' ^""'^ °^^y ^^ determined by nitrate of silver; and of sulphurii So^' «Y T^'^.fl^'y'^' Aquafortis may be purified in a great measure, b? reSlT rMJnJ ^^"*^^ ^'^^' ""J""""^ ^^^^''^ ^»^"'^ ^^'^^ comes over, as t contains the aS,^umrfh"''T^''T^"^ the middle portion as genuine nitrii acid ; and ^v ng a residuum m the retort, as being contaminated with sulphuric acid. lu^TTrr.T'^^A ^ ^°^* ^^^ ^^^" ^'^ abundantly imported into Europe from Peru, it has J^fd Wn^^*^.^-^ T^y manufacturers in preference to nitre for the extraction of nitr" acid because it is cheaper, and because the residuum of the distillation, be n " sulphate Ltl^:'g:,^er;Vr'n\^;^^t^ "^ ^^^^^^^^ ^^^"l, ^^-^ -*-^^' ^^^- - T^eorZ^ TJu2 ^M ^^ furnace is the apparatus employed. Nitric acid of specific gravity 1^ 2lXtme"^iirou:tV ^ portion of it fs decomposS sVen^S^itTxha?p/Jh> ^^ *' produced, which gives it a straw-yellow tinge. At iWs !;l»wn n Y^'^^ ""^ "'■^"'^ ^"™«s> which have a peculiar/ thou-h not yery dL^ Se t deTs ; aTtS>r''" '^""'t' '''^J,'^ ^^^^^ "'^^-'^^ tastes extremely Lu^^^ T?c greaiesi aensiiy at which it can be obtained is 1-51 or perhans 1-52 at fiO" F in whJnh .ndra 85 o^i: r;.' orof'i'v" ?"™' '"^^ l"i™--ts of 26-15 pa™ by ^eigKa^le. men of sDecmc eravitv > 7f."r? "^ ""! '^''' «*^' »"■» ^ volumes of the%econd. ' I j'.M i • ' • *' , ' """^ of '"40, at 246° F. If ia acid stron.er tliaa l-iUtt bed.st.lled m a retort, It gradually becomes weaker ; and H" weaker than r42r4adf lUly becomes stronger, .Ul it assumes that standard denslly Add orspecffic ^w"; 276 NITRIC ACID. NITROGEN, DEUTOXIDE OF. 277 I i 1 t i ( i::ii i> lA 1-485 has no more action upon tin than water has, though when either stronger or weaker it oxydizes it rapidly, and evolves fumes of nitrous gas with explosive violence. In my two papers upon nitric acid published in the fourth and sixth volumes of the Journal of Science (1818 and 1819), I investigated the chemical relations of these phe- nomena. Acid of 1-420 consists of 1 atom of dry acid, and 4 of water ; acid of 1-48D, of 1 atom of dry acid, and 2 of water; the latter compound possesses a stable equi- librium as to chemical agency ; the former as to calorific. Acid of specific gravity 1-334, consisting of 7 atoms of water, and 1 of dry acid, resists the decomposing agency of light. Nitric acid acts with great energy upon most combustible substances, simple or compound, giving up oxygen to them, and resolving itself into nitrous gas, or even azote. Such is the result of its action upon hydrogen, phosphorus, sulphur, charcoal, sugar, gum, starch, sQver, mercury, copper, iron, tin, and most other metals. From muriatic to nitric acid the transmission is easy, though nitnc acid is never obtained as the waste product of any chemical operation. Its manufacture is invariably the primary object of the process by which it is procured. The ordinary method consists in heating together, in a distillatory apparatus, a mi^rture of nitrate of soda or potash with sulphuric acid. In this way. the sulphuric acid unites with the soda or potash, as the case may be, forming commercial products, also salt cake and sal- enixen : whilst the nitric acid combines with the water of the suli)huric acid, and, pass- ing away under the influence of the heat, is condensed in the receiver of the apparatus. A decomposition of this kind is sometimes denominated a simple decomposition ; but m reality it is not so, as the transfer of the water completes the cycle of elective afiimty. A Table of Nitric Acid, by Dr. Ure. Specific I gfravity. Liq. Acid in 100 1-5000 1-4980 1-4960 1-4940 1-4910 1-4880 1-4850 1-4820 1-4790 1-4760 1-4730 1-4700 1-4670 1-4640 1-4600 1-4570 1-4530 1-4500 1-4460 1-4424 1-4385 1-4346 1-4306 1-4269 1-4228 100 99 98 97 96 95 94 93 92 91 90 89 88 87 86 85 84 83 82 81 80 79 78 77 76 Dry acid in 100 79-700 78-903 78-106 77-309 76-512 75-715 74-918 74-121 73-324 72-527 71-730 70-933 70-136 69-339 68-542 67-745 66-948 66-155 65-354 64-557 63-760 62-963 62-166 61-369 60-572 Specific gravity. 1-4189 1-4147 1-4107 1-4065 1-4023 1-3978 1-3945 1-3882 1-3833 1-3783 1-3732 1-3681 1-3630 1-3579 1-3529 1-3477 1-3427 1-3376 1-3323 1-3270 1-3216 1-3163 1-3110 1-3056 1-3001 Liq Acid ialOO 75 74 73 72 71 70 69 68 67 66 65 64 63 62 61 60 59 58 57 56 55 54 53 52 51 Dry acid in 100 59-775 58-978 58-181 57-384 56-587 55-790 54-993 54-196 53-399 52-602 51-805 51-068 50-211 49-414 48-617 47-820 47-023 46-226 45-429 44-632 43-835 43-038 42-241 41-444 40-647 Specific gravity. 1-2947 1-2887 1-2826 1-2765 1-2705 1-2644 1-2583 1-2523 1-2462 1-2402 1-2341 1-2277 1-2212 1-2148 1-2084 1-2019 1-1958 1-1895 1-1833 1-1770 1-1709 1-1648 1-1587 1-1526 1-1465 Liq. Acid in 100 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32 31 30 29 28 27 26 Dry acid in 100. 39-850 39-053 38-256 37-459 36-662 35-865 35-068 34-271 33-474 32-677 31-880 31-083 30-286 29-489 28-692 27-895 27-098 26-301 25-504 24-707 23-900 23-113 22-316 21-519 20-722 Specific gravity. 1-1403 1345 1286 1227 1168 1.1109 1051 1-0993 1-0935 1-0878 1-0821 1-0764 1-0708 1-0651 1-0595 1-0540 1-0485 1-0430 1-0375 1-0320 1-0267 1-0212 1-0159 10106 1-0053 Liq. Acid in 100 Dry acid in 100. 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 19-925 19-128 18-331 17-534 16-737 15-940 15143 14-346 13-549 12-752 11-955 1M58 10-361 9-564 8-767 7-970 7-173 6-376 5-579 4-782 3-98t 3-188 2-391 1-594 0-797 It has been proposed, and even carried into practice, to decompose nitrate of soda by the action of boracic acid, so as to produce biborate of soda, or borax, and thus render the nitric acid a secondary product The success of this process depends, however, upon a circumstance of a somewhat curious kind. Strong nitric acid is much more volatile than weak acid; and hence it is more easily expelled from its combination with soda in a concentrated than in a diluted form. Now, boracic acid has 3 atoms of water in its crystallized condition ; therefore, if we take 2 atoms of this acid, we have 6 atoms of water to unite with the 1 atom of nitric acid capable of being disengaged from nitrate of soda; whereas this quantity of nitric acid neeeds at most but 2 atoms. The secret, therefore, is to dry the boracic acid in the first instance, so as to get rid of the surplus water; and this is easily done at a temperature of 212° Fahr., at which two-thirds of a the water readily leave the boracic acid, and thus aflFord a mono-hydrated compound, 2 atoms of which contain precisely the amount of water needed for one atom of nitric acid, and also of the boracic acid requisite for the production of the biborate of soda. There are some peculiarities connected with the application of the necessary tempe- rature; but they are of less importance. The biborate of soda is afterwards dissolved in hot water, and crystallized. This process has been patented in France within the last few years, by a M. Mallet, of Paris. One of the most extensive uses of nitric acid, and for which, indeed, it is chiefly fabricated, is the manufacture of oxalic acid. Nitric Acid, anhydrotis. — By treating nitrate of silver with perfectly dry chlorine^ M. Deville has succeeded in isolating anhydrous nitric acid, the existence of which was demonstrated by numerous analyses. This beautiful substance is obtained in colorless crystals, which are perfectly brilliant and limpid, and may be procured of considerable size ; when they are slowly deposited in a current of ^as rendered very cold, their edges are a centimetre in length. These crystals are prisms of 6 faces, wnich appear to be derived from a right prism with a rhombic base. They melt at a temperature not much exceeding 85-5 Fahr, ; their boiling point is about 113°; and at 60° the ten- sion of this substance is very considerable. In contact with water it becomes very hot, and dissolves in it without imparting color, and without disenga^ng any gas ; it then produces with barytes the nitrate of that base. When heated, its decomposition ap- pears to commence nearly at its boiling point This circumstance is an obstacle to the determination of the density of its vapor by the process of M. Dumas. The process by which M. Deville obtained anhydrous nitric acid is very simple ; but the readiness with which it penetrates tubes of caoutchouc renders it necessary to unite all the pieces of the apparatus by melting them. The following is the process : — The author employs a U-shaped tube capable of containing 500 gr. of nitrate of silver dried in the apparatus at 356° Fahr. in a current of dry carbonic acid gas. Another very large U tube is connected with this, and to its lower part is attached a small spherical reservoir ; it is in this resorvoir that a liquid is deposited which always forms during the operation, and which is exclusively volatile (nitrous acid?) The tube con- taining the nitrate of silver is immersed in water covered with a thin stratum of oil, and heated by means of a spirit lamp communicating with a reservoir at a constant level. The chlorine issues from a glass gasometer, and its displacement is effected by a slow and constant flow of concentrated sulphuric acid. The chlorine must afterwards pass over chloride of lime, and then over pumice-stone moistened with sulphuric acid- At common temperatures no effect appears to be produced. The nitrate of silver must be heated to 203° Fahr., the temperature being then quickly reduced to 136° or 154°, but not lower. At the commencement, hyponitrous acid, distinguishable by its color and ready condensation, is produced; and when the temperature has reached its lowest point, the production of crystals begins, and they soon choke the receiver, cooled to 6° below zero; they are always deposited upon that part of the receiver which is not im- raei-sed in the freezing mixture, and M. Deville states that ice alone is sufficient to oc- casion their formation. The gases are colored, and the small sphere of the cooled tube contains a small quantity of liquid, which must be taken from the apparatus before the nitric acid is removed to another vessel ; this latter operation is readily effected by replacing the current of chlorine by one of carbonic acid. The condenser is then to be no longer cooled, and the vessel for receiving the crystals is to be immersed in a freezing mixture; this is fastened to the producing apparatus by means of a caoutchouc tube furnished with amianthus. The chlorine should pass very slowly at the rate of about 3 or 4 li- tres in 24 hours. All the gas, however, is not absorbed by the nitrate of silver. Oxy- gen is evolved, the volume of which appears to be equal to that of the chlorine em- ployed. An apparatus thus constructed operates day and night without watching, care being however taken to renew the sulphuric acid which displaces the chlorine, the spirit of the lamp, and the ingredients of the freezing mixture. The author states that he shall forward hereafter a more complete memoir, in which he will describe the chemical properties of the anhydrous nitnc acid, and detail the results of his researches on the action of ehlorine and hypochlorous acid on the salts of silver. NITROGEN, DEUTOXYDE OF ; NUrous gas, Nitnc oxyde (Deutoxyde d'azote, Fr. t Stichstoffoxydy Germ.) is a gaseous body which may be obtained by pouring upon copper or mercury, in a retort, nitric acid of moderate strength. The nitrous gas comes over in abundance without the aid of heat, and may be received over water freed from air, or over mercury, in the pneumatic trough. It i^ elastic and colorless ; what taste and smell It possesses are unknown, because the moment it is exposed to the mouth or nostrils, it absorbs atmospherical oxygen, and becomes nitrous or nitric acid. Its specific gravity is 1-0393, or 1-04 ; whence 100 cubic inches weigh 36-66 gr. Water condenses not more than TjL of its volume of this gas. It extinguishes animal life, and the flame of many 278 NITROGEN GAS. NUTMEG fit 1 1 I I ''■MM' [V: hi combustibles ; but of pbosphorns well kindled, it brightens the flame in a most re- markable degree. It consists of 47 parts of nitrogen gas, and 63 of oxygen gas, by weight; and of equal parts in bulk, without any condensation; so that the specific gravity of the deutoxide of nitrogen is the arithmetical mean of the two constituents. The constitution of this gas, and the play of affinities which it exercises in the formation of sulphuric acid, are deeply interesting to the chemical manufacturer. The Hyponitrous acid^Satpetrigesaure, Germ.), like the preceding compound, deserve* notice here, on account of the part it plan's in the conversion of sulphur into sulphuric acid, by the agency of nitre. It is formed by mingling four volumes of deutoxide of nitrogen with one volume of oxygen ; and appears as a dark orange vapor, which is condensable into a liquid at a temperature of 40° below zero, Fahr. When distilled, this liquid leaves a dark yellow fluid. The pure hyponitrous acid consists of 37 "12 nitrogen, and 62*88 oxygen ; or of two volumes of the first, and three of the second. "Water converts it into nitric acid and deutoxide of nitrogen ; the latter of which escapes with effervescence. This acid oxidizes most combustible bodies with peculiar energy ; and though its vapor does not operate upon dry sulphurous acid, yet, through the agency of steam, it converts it into sulphuric acid, itself being simultaneously trans- formed into deutoxide of nitrogen ; ready to become hyponitrous acid again, and to perform a circulating series of important metamorphoses. See Sulphuric Acid. NITROGEN, PREPARATION OF. Tliis process is founded on the decomposition of nitrate of ammonia, which, as is already known, is resolved into nitrogen and wa- ter under the influence of heat ; but as this salt is difficult to prepare, I replace it by a mixture of an alkaline nitrate of potash and sal ammoniac, a mixture which contains the elements of nitrite of ammonia and chloride of potassium. The best method of obtaining the nitrite of potash in a convenient state is to pass nitrous acid gas, formed by the action of 10 parts of nitric acid on one part of starch, through a solution of caustic potash having a sp. gr. 1'38, until the solution acquires an acid reaction ; and then to add a little caustic potash, so as to render it distinctly alkaline. As the solu- tion thus prepared does not undergo alteration from keeping, it may be held in readi- ness ; and when the nitrogen is required, it is only necessary to mix one volume of the above solution with three volumes of a concentrated solution of sal-ammoniac, and to heat the mixture in a flask. The disengagement of the gas takes place almost im- mediately, and continues with great regularit}'. As it is necessary, in order to make tiie gas pure, that the nitrate should be alkaline; there will be a disengagement at the same time of a little ammonia, but this is of no consequence ; if the nitrogen be required completely free from ammonia, it is sufficient to pass the gas through a vessel containing water acidulated with a little sulphuric acid. The following are the experiments by which I have satisfied myself of the purity of the nitrogen thus obtained : — 1. After freeing the gas from ammonia as above described, it was conveyed into a tube containing a mixture of zinc, sulphuric acid, and water ; into the presence, there- fore, of nascent hydrogen. The experiment was continued for some time, and when concluded I could not detect a trace of ammonia in the solution. The solution was also negative on testing it with sulphate of iron and dilute sul- phuric acid. 2. I placed in a glass tube, such as is used for organic analysis, a determined quanti- ty of copper recently reduced by hydrogen, and exposed this for half an hour to the action of a red heat and of a current of the nitrogen washed and subsequently dried by passing it through pumice-stone wetted with oil of vitriol ; taking at the same time the precaution not to heat the tube until all the atmospheric air had been displaced by the nitrogen. This experiment was repeated several times, without any alteration being observed either in the exterior appearance of the copper or in \t& weight NITROGEN GAS, or AZOTE (Eng. and Fr.; Sticksioffgas, Germ.), constitutes about 79 hundredths of the bulk of the atmospheric air ; it is copiously disengaged from several mineral springs, as from the natural basins of hot water which supply the baths of Leuk, near the Gemmi in Switzerland, and from other springs, in the Pyrenees, in Ceylon, South and North America, &c. It exists also in flesh and most animal sub- stances, as well as in some vegetable products, being one of their essential constituents. When phosphorus is burnt within a jar filled with air, standing over water in the pneu- matic trough, it consumes or absorbs the oxygen, and leaves nitrogen, which may be ren- dered pure by agitation with water. By exposing nitrite of ammonia to heat in a retort, nitrogen comes over alone in great abundance ; for the hydrogen of the ammonia is suf- ficient to saturate the oxygen of the acid, and to convert it into water ; while the nitro- gen of both constituents is set at liberty. By transmitting chlorine through water of ammonia, or digesting lean flesh in warm nitric acid, nitrogen may also be obtained. This permanently elastic gas is destitute of color, taste, and smell ; it has a specific gra- 279 vity of 0-976, air being 1-000. Hence 100 cubic inches of it weigh 29-7 gr. It extin- NUKOGEN, PROTOXYDE OF, Nitrous oxyda (Proioxyde d' azote, Fr.: SiicksiofT- oxydul, Germ.), is a gas which displays remarkable powers when breathed, causing in many persons unrestramable feelings of exhilaration, whence it has been called the laSch- ing ormtoxicaling gas. It is prepared by exposing crystallized nitrate of ammonia to a heat of about 3o0° Fahr. m a glass retort. It is much denser than the air of the atmo- sphere, having a spec. grav. of 1-527; whence 100 cubic inches weigh 46-6 grains. It consists of 63-64 parts of nitrogen, and 36-36 of oxygen, by weight ; or of two volumes of nitrogen and one volume of oxygen condensed by reciprocal attraction into two volumes. It is colorless, and possesses all the mechanical properties of the atmosphere Water previously freed from air absorbs its own volume of this gas; and thus affords a ready criterion for estimating its freedom from incondensable gases, as oxygen, nitrocen and Its deutoxyde. Several combustibles bum in this gas with an enlarg^^ blue fndV^ yivid flame ; and it relumes a taper which has been blown out, provided its tin h#. r«i hot. By powerful pressure it may be liquefied. See Gas. ^ NITRO-MURIATIC ACID, j9qua regia (Jcide nitro-muriatique, Fr • Salveter sah saure Konisswasser, Germ.) is the compound menstruum invented by the alchemists foi dissolving gold. If strong nitric acid, orange-colored by saturation with nitrous gas (deutoxyde of azote), be mixed with the strongest liquid muriatic acid, no other efi-ect is produced than might be expected from the action of nitrous acid of the same streneA upon an equal quantity of water ; nor has the mixed acid so formed any power of acting upon gold or platma. But if colorless aquafortis and ordinary muriatic acid be mixed toge her, the mixture immediately becomes yellow, and acquires the power of dissolving these two noble metals. When gently heated, pure chlorine g^^.^, fiomit, and its color becomes deeper; when further heated, chlorine still rises, but no^ mixed wiUi nitrous acid gas. If the process has been very long contLed, tm the color becomes very dark, no more chlorine can be procured, knd the liquor has los the power of dissolving gold. It then consists of nitrous and muriatic acids It an^are therelore that aqua regia owes its peculiar properties to the mutual deco^^! ion of the nitric and muriatic acids; and that water, chlorine, and nitrous acid cTie the results of hat reaction. Aqua regia does not, strictly spewing, oxyd'^sm and platinum; it causes merely their combination with chlorine. It mfy b^ c^r^pf^eJ ^Lwr7 ^t"'^i proportions of the two acids; the nitric being commonly of spS^ graMty 1-34; the muriatic, of specific eravitv 1-18 or MQ ^rn^f.rr.^^ o '■v*^^^'^^ at others 6 parts of the miriatic acid S^mhJllhl ofLr'^nTZ^-^^'u' ^""^ riate of ammonia, instead of muriatic acid? i^lM^'io Ll^'a^d for^i'Sc^^^^ as for making a solution of tin for the dyers. An aqua regia may also be preS^ dissolving nitre in muriatic acid. h » y ue preparea oy NITROUS ACID (jidde nitreux, Fr. ; Salpetrige salpdermure, Germ.) may be wo- cm-^ by distilling, in a coated glass retort, perfectly dry'^nitrate of lead, intH^gSs^Jt c^ver surrounded with a freezing mixture. The acid passes over in vapor, and cond?nS n?h!^;'/ ' oxygen gas escapes through the safety tube ; while oxyde Jf lead remains nhric ac'Jd Ti ?f '^i' '''"/'• ^^'""^^ "'^^ "^^y ^^^^ ^' «^^^i'^«J ^y 'Ji^'illi"? strong fumTg JiJ^ # I ' IJ''^ ^°7^.'' P"""^'^^^ temperature, and rectifying what comes over. At 4<»-i «ro Fahr., this acid is coloriess ; at 32' it is wax yellow; at Q(P it has an orange hue It possesses a strong smell, has a very pungent, acrid, sour taste, and a specie |rav"^ PV.hr t;.K*rT''"^ decomposes organic bodies, staining them yellow. It boil, at 8i^ *atir. with the disengagement of red or orange fumes. Its constituents are 41-34 of JrmpT7«Qi^'^^ 58-66 of anhydrous nitric acid ; or ultimately 30 68 nSogen - 1 ^^rt^J^^ acid, constitutes the orange- ^^I^^f^^^^.:^^ '^--'^^'^ ^- -^-^=^ - water in their ins^^bte^s. ^^^ ^^'"*'^" "^""^ °^ '^^ P^^^' ^^''"* ^"'^' «P<*^ w^i<^»» t^^ cochineal J!}IZ^^^J^T.^'^' ^'y* i»ft*,fea which growTlT'Jh: of the fruit called mace nnd n . ^^'' *'^^ "^ ^""^ "^'"^^^^ ? ^""^ ««^>' those porUons cLn:l Jr ; ^'^"^^.'"*ce and nutmeg are sent into the market. The entire fruit is a species of drupa of an ovoid form, of the size of a peach, and furrow^ bi^ud^Lllr Jd bv rmac'e anJ'lhir' ^'''''^^ T '''^' ^«"^^^"^ '^^ ^ '^^^ sM, wlichts ^^unjl fc^ireTlit^to^^^^^^^^^^ 'Vhet^li:; trriL Js \t:e'^"' -'''' ^'T' ""' ^^ April, which is the best; one in Aug^Hnd o're^ri^'eLm^r""' '^'^""^'^ ""' '» u n '4 280 OILS, UNCTUOUS. Tl ■1 ■-! i " Good nutmegs should be dense, and feel heavy in the hand. When they have been perforated by worms, they feel light, and though the holes have been fraudulently stojpped, the unsound ones may be easily detected by this criterion m*tmeffs aflFord two oily products. 1. Butter of nutmeg, vulgarly called oil of mace 18 obtamed m the Moluccas, by expression, from the fresh nutmegs, to the amount of •*tT- ""u?^ ^'i^i'T ^^'«,*'*- " '^ * reddish yellow butter-like substance, interspersed with Jight and dark streaks, and possesses the agreeable smell and taste of the nutraeff from the presence of a volatile oil. It consists of two fats ; one reddish and soft, soluble J n cold alcohol ; another white and solid, soluble in hot alcohol 2. The volatile oil is solid, or a stereoptene, and has been styled Myristicine. in^?i^'^1n^.a^^^i?L^^^'\^^^^'-'/^P^^'^^^'^2^^^^' exported, 1860, 151,526 Iba.. ,«/?oo',v ' , ° ^^ ' retained for home consumption, 1850, 168,403 lbs., in 1861 194,132 lbs.; duty received, 1350, 19,042/., 1851, 21,913/. NUT OIL. See Oils, Unctuous. NUX VOMICA, a poisonous nut, remarkable for containing the vegeto-alkali OILS, UNCTUOUS. 281 O. OAK BARK See Tan. iK^f^T^l ^^,!"^"5 ^''•,i ^«/«". C^erm.) The composition of oata is less known than tnat of the other Cercaha. Vogel found that 100 parts of oats afforded 66 parts of flour or meal, and 34 parts of bran ; but this proportion would depend upon the quality of the grain. The flour contains 2 parts of a greenish-yellow fat oil ; 8-26 of bitterish sweet extractive; 2-5 of gum ; 3 30 of a gray substance, more like coagulated albumen than gluten; 59 of starch; 24 of moisture (inclusive of the loss). Schrader found in the ashes of oats, silica, carbonate of lime, carbonate of magnesia, alumina, with oxide« of manganese and iron. -» -> -f OBSIDIAN, is a glassy-looking mineral, with a large conchoidal fracture, and of a /^r^'/ro iJ *""%7^'''^ ??^^^ "^^""^ ^^ *^^ blow-pipe before it melts into a white enamel. OCHRE, yellow and brown (Ocre, Fr. ; Ocker, Germ.); is a native earthy mixture of sihca and alumina, colored by oxide of iron, with occasionally a little calcareous matter and magnesia. Ochre occurs in beds some feet thick, which lie generally above the oolite, are covered by sandstone and quartzose sands more or less ferruginous and are accompanied by gray plastic clays, of a yellowish or reddish color; all of them substances which contribute more or less to its formation. The ochry earths are pre- pared for use by grinding under edge millstones, and elutriation. The yellow ochres may be easily rendered red or reddish brown by calcination in a reverberatory oven, which oxidizes their iron to a higher d^ree. Native red ochre is caUed red chalk and reddle in England. It is an intimate mixture of clay and red uron ochre ; is massive ; of an earthy fracture j is brownish-red, blood- red, stains and writes red. The oxyde of iron is sometimes so considerable, that the ochre may be reckoned an ore of that metal. The ochre beds of England are in the iron sand, the lowest of the formations which intervene between the chalk and oolites. Beds of fullers earth alternate with the iron sand. The foUowing is a section of the ochre pits at Shotover Hill, near Oxford :- Beds of highly ferruginous grit, forming the summit of the hill Gray sand Ferruginous concretions Yellow sand Cream colored loam Ochre . 6 feet. 3 do. 1 6 4 6 inches. Beneath this, there is a second bed of ochre, separated by a thin bed of clay Bole, or Armenian bole; called also Lemnian earth, and terra si?illata, because when refined it was stamped with a seal ; is massive, with a conchoidal fracture, a feeble lustre, reddish-yellow or brown, a greasy feel ; adheres to the tongue, spec. grav. 1-4 to 2-0 It occurs in the island Stalimene (the ancient Lesbos), and in several other places, especially at Sienna ; whence the brown pigment called terra di Siena. OILS (HmUs, Fr. ; Oele, Germ.), are divisible into two great classes : the fat or fixed oUs, hmles grasses, Fr. ; Fette oele, Germ. ; and the essential or volatile oils, HuUes vola^ ttU$, Fr. i Fluchttge, aethensche oele. Germ. The former are usually bland and mild to to the taste; the latter hot and pungent The term distilled, applied also to thp la«i clas^ IS not so correct^ since some of them are obtained by expression, as the whoie of the first class may be, and commonly are. All the known fatty substances found in organic bodies, without reference to their vegetable or animal origin, are, according to their consistence, arranged under the chemical heads of oils, butters, and tallows. They all possess the same ultimate con- BUtuents, carbon, hydrogen, and generally oxygen, and in nearly the same proportions. The following is a list of the Plants which yield the ordinary Unctuous Oils of commerce : 1. 2. 8. 4. 6. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. J7. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. 36. 37. 38. 39. 4©. 41. Linum usitatissimum et perenne Corvlus avellana ) Juglans regia J * " Papaver somniferum Cannabis sativa ' Sesamum orientale - - G, Olea Europea - - - G. Amygdalus communis - - G. Guilandina mohringa - - G. Cucurbita pepo, and melapepo D. Fagus silvatica - - G. Sinapis nigra et arvensis - G. Helianthus annuus et perennis D. Brassica napus et campestris - G. Ricinus communis - - D. Nicotiana tabacum et rustica - D. PrunuR domestica - - G. Vitis vinifera - - - D. Theobroma cacao - - G. Cocos nucifera - - G. Cocus buiyracea vel avoira elais G. Laurus nobilis - - - G. Arachis hypogeea - - G. Vateria indica - - - G. Hesperis matronalis - - D. MyagTum sativa - - D. Reseda luteola - - D. Lepidium sativum - - D. Atropa belladonna - - d! Gossypium Barbadense - D. Brassica campestris oleifera - G. Brassica praecox - - G. Raphanus sativus oleifer - G.' Prunus cerasus . • G. Pyrus mains - . - g! Euonymus Europaeus - - g! Comus sanguinea . - g! Cyperus esculenta - . g! Hyociamus niger - - g! -^sculus hippocastanum - g! Pinus at ies - . - D.* D. D. D. D. Linseed Oil Nut oil - Poppy oil ... Hemp oil - Oil of sesamum Olive oil - Almond oil Oil of behen or ben Cucumber oil Beech oil - Oil of mustard Oil of sunflower - Rape-seed oil Castor oil - Tobacco-seed oil - Plum-kemel oil Grape-seed oil Butter of cacao Cocoa-nut oil Palm oil - Laurel oil - I Ground-nut oil Piney tallow Oil of Julienne Oil of camelina Oil of weld-seed - Oil of garden cresses Oil of deadly nightshade Cotton-seed oil Colza oil - Summer rape-seed oil Oil of radish-seed - Cherry-stone oil - Apple-seed oil Spindle-tree oil Comil-berry tree oil Oil of the roots of cyper grass Henbane-seed oil - Horse-chestnut oil - Pinetop oil Specific graTity. 0-9347 0-9260 0-9243 0-9276 a 0-9176 - 0-9180 . 0-9231 - 0-9226 - 0-9160 » 0-9262 - 0-9136 - 0-9611 - 0-9232 0-9127 0-9202 0-892 4» 0-968 m 0-926 - 0-9281 - 0-9252 - 0-9358 - 0-9240 - 0-9250 _ 0-9136 - 0-9J39 - 0-9187 - 0-9239 - 0-9380 iss 0-9180 - 0-9130 - 0-927 - 0-285 TZ'lretLTiTfhy^!^"'^'}'^^ through the organs of vegetable and animal nature, iney are lound in the seeds of many plants, associated with mucilaL'e especially iu ^eXl tt o^lvt^'tt^^^^^^^ occasionally in the fleshy pulp su^riuXg 1" rndLallv in thP Vont I ^ kernels of many fruits, as of the nut and almond tree, matt^ri/cn^ ^n.W^ ^*^^i? ^'^^ ""l^^" ^^^^ ^^ P^*"^' I" *»in^«l bodies, the oily matter occurs enclosed in thin membranous cells, between the skin and the flesfi between the muscular fibres, within the abdominal cavity in the omentum uponThe uitestme^ and round the kidneys, and in a bony receptacle of theTull of Zspel Vol. IL 2 282 OILS, UNCTUOUS. OILS, UNCTUOUS. 283 i ) :\ '.\ maceti whale ; sometimes in special organs, as of the beaver ; in the gall bladder, <"'«' '"■» water, and expressed, yields . sUll decree Fahf Tuea^ foTfw/nl'vT"^ in clean ,„„„ in ,„ apartment heated to the 60tl. .rl"<^fed"1;- aVZ': Ind'rn'Ll,?rn'.„''Sr; l';fe," " ™" ""^ '"•" *'""« ^'' ^'"''^ 286 OILS, UNCTUOUS. OILS, UNCTUOUS. 287 §\ \ VI! tnem strongly between a series of cast iron plates, in a hydraulic press ; without heftt at first, and then between heated plates. The first oil is the purest, and least apt to become rancid. It should be refined by filtering through porous paper. Next to olive oil, this species is the most easy to saponify. Bitter almonds, being cheaper than the sweet, are used in preference for obtaining this oil, and they aflbrd an article equally bland, wholesome, and inodorous. But a strongly scented oil may be procured, accord- ing to M. Planche, by macerating the almonds in hot water, so as to blanch thom then drying them in a stove, and afterwards subjecting them to pressure. The voiatil* oil of almonds is obtained by distilling the marc or bitter almond cake, along with water. See Press Hydraulic, and Stearine. Linseed, rapeseed, poppyseed, and other oleiferous seeds were formerly treated for the extraction of their oil, by pounding in hard wooden mortars with pestles shod with iron, set in motion by cams driven by a shaft turned with horse or water power, then the triturated seed was put into woollen bags which were wrapped up in hair-cloths, and squeezed between upright wedges in press-boxes by the impulsion of vertical rams driven also by a cam mechanism. In the best mills upon the old construction, the cakes obtained by this first wedge pressure were thrown upon the bed of an edge-mill, ground anew and subjected to a second pressure, aided by heat now, as in the first case. These mor- tars and press-boxes constitute what are called Dutch mills. They are still in very general use both in this country and on the Continent ; and are by many persons sup- posed to be preferable to the hydraulic presses. The roller-mill, for merely bruising the linseed, &c., previous to grinding it under edge- ftones, and to heating and crushing it in a Dutch or a hydraulic oil-mill, is represented in figs. 101?. and 1013. The iron shaft a, has a winch at each end, with a heavy fly-wheel upon the one of them, when the machine is to be worked ly hand. Upon the opposite end is a pu '- ley, with an endless cord which passt s round a pulley on the end of the fluted roller 6, and thereby drives it. This fluted roller 6, lies across the hopper c, and by its agitation causes the seeds to descend equably through the hopper, between the crushing rollers d, e. Upon the shaft a, there is also a pinion which works into two toothed wheels on the shafts of the crushing cylinders CL and e, thus commu- nicating to lliese cylinders motion in opposite directions. /, g ar«; two scraper- blades, which by means of the two weights h, hy hanging upon levers, are pressed against the surfaces of the cyl- inders, and remove any seed-cake from them. The bruised seeds fall through the slit i of the case, and are received into a chest which stands upon the board k. Machines of this kind are now usually driven by power. Hydraulic presses have been of late years introduced into many seed-oil mills in this country ; but it in still a matter of dispute whether they, or the old Dutch oil-mill, with bags of seed compressed between wedges, driven by cam-stamps, be the preferable ; that is, aflTord the largest product of oil with the same expenditure of capital and power. For figures of hydraulic presses, see Press, and Stearine. This bruising of the seed is merely a preparation for its proper grinding under a pair of heavy edge stones, of granite, from 5 to 7 feet in diameter; because unbruised seed is apt to slide away before the vertical rolling wheel, and thus escape trituration. The edge-mill, for grinding seeds, is quite analogous to the gunpowder-mill represented in fig. 740, page 980. Some hoop the stones with an iron rim, but others prefer, and I think justly, the rough surface of granite, and dress it from time to time with hammers, as it becomes irregular. These stones make from 30 to 36 revolutions upon their horizontal bed of masonry or iron in a minute. The centre of the bed, where it is per- forated for the passage of the strong vertical shaft which turns the stones, is enclosed by a circular box of cast iron, firmly bolted to the be^-stone, and furnished with a cover. This box serves to prevent any seeds or powder getting into the step or socket, and obstructing the movement. The circumference of the mill-bed is formed of an upright rim of oak- plank, bound with iron. There is a rectangular notch left in the edge of the bed, and corresponding part of the rim, which is usually closed with a slide-plate, and *• opened only at the end of the operation, to let the pasty seed-cake be turned out by the oblique arm of the bottom scraper. The two parallel stones, which are set near eacn other, and travel round their circular path upon the bed, grind the seeds not merely bv their weight, of three tons each, but also by a rubbing motion, or attrition • because their periphery being not conical, but cylindrical, by its rolling upon a plane surface, must at every instant turn round with friction upon their resting points. Stron«' cast-iron boxes are bolted upon the centre of the stones, which by means of screw clamps seize firmly the horizontal iron shafts that traverse and drive them, by passing into a slit-groove the vertical turning shaft. This groove is lined with strong plates of steel, which wear rap- idly by the friction, and need to be frequently renewed. The seeds which have been burst between the rolls, or in the mortars of the Dutch mills, are to be spread as equably as possible by a shovel upon the circular path of the edge-stones, and in about half an hour the charge will be sufficiently ground into a paste. This should be put directly into the press, when fine cold-drawn oil is wanted. But in general the paste is heated before being subjected to the pressure. The pressed cake if again thrown under the edge-stones, and, after being ground the second time, should be exposed to a heat of 212° Fahr., in a proper pan, caUed a steam-kettle, before being subjected to the second and final pressure in the woollen bags and hair-cloths. Fig. 1014 is a vertical section of the steam-kettle of Hallette, and^g.l015is*a view of the seed-stirrer. a, is the wall of ma- sonry, upon which, and the iron pillars b, the pan is supported. It is enclosed in a jacket, for admitting steam into the intermediate space d, rf, d, at its sides and bottom, c, is the middle of the pan in which the shaft of the stirrer is planted upright, resting by its lower end in the step e ; /, is an opening, by which the contents of the pan may be emptied; g, is an orifice into which the mouth of the hair or worsted bag is inserted, in order to receive the heated seed, when it is turned out by the rotation of the stirrer and the with- drawal of the plug/ from the discharge aperture; hy is the steam induction pipe; and t, the eduction pipe, which serves also to run oflf the condensed water. The hydraulic oil-press is generally double; that is, it has two vertical lams placed parallel to each other, so that oth*»r «i\ip .-c Ko.«„ AX. J, rj.^ ^ ^^^'^ °"^ ^^^^ ^s ^^^^^ pressure, the other side is being discharged. The bags of heated seed-paste or meal are put into ca t-.ron cases which are piled over each other to the number of 6 or 8, upon the pi^ Ss of seeH flo^r ^ V^ ^^ P'^''' '"^ ^ well-going establishment, should work 38 pounds of seed-flour every 5 minutes. Such a press will do 70 quarters of Unseed in a:h'l7^ula;^eT?&h"''' '''' labor of Sne man at 20,.\VX"ee 'boyTaf 5 " ^ge-'stones. '^ ^''''^' ^" ""^'^ '^ ^^"' ^^"^ ^'^^ ^^^ ^^U^ and the no{ertikefi^L'"L'^rn!l'"''^r? ^'' ^' Woo.sey, for the foUowing most valuable seld-VushlngLg^^^^^^^^^ P^^^^^"^ ^^^' ^^' '•^--^^ upon the subject of se^'^wUl^^etd mit on'^T"'^ "P*^'^ '^^ ^1"^^^ ^^ '^^ «°»Ployed. Heavy ^e7^ Z iZen ^l'Z\l^f '^r^ ""^«'' * *»«^ «""' a"d where the flax is not SS bushel nrnLlw ^^' ^^^ "^^'^^^ «^ ^''''^^ ^^^^^ froM 48 to 52 Ibs. per Sr ^Infj^Z^^lfV^TJ'''' ^^^''^^^ i« 49 lbs., or 392 Ibs. per imperial quarter. I inspected one of the seed-crusher's books, and the average of 15 trials of a m }>'i \ ti ^ li It 288 OILS. UNCTUOUS. quarter each of different seeds in the season averaged 14J galls, of 7| lbs. each; say, 109 lbs. of oil per quarter. This crusher, who uses only the hydraulic press, and one pressing, informed me that — Archangel seed will yield from - - - - 15 to 16 galls, (of 7^ lbs. each) Best Odessa - - - -- - -18 and even 19 galls. Good crushing-seed ------ 16| do. Low seed, such as weighs 48 lbs. per bushel - 13| do. •* The average of the seed he has worked, which he represents to be of an inferior quality, for the sake of its cheapness, yields 14 J galls, per quarter. I had some Ameri- can seed which weighed 52J lbs. per imperial bushel, ground and pressed under my own observation, and it gave me 111 lbs. oil; that is to say, 418 lbs. of seed gave 111 lbs. oiI=26yS^^ per cent. A friend of mine, who is a London crusher, told me the oil varied according to the seed from 14 to 17 galls. ; and when you consider the relative value of seeds, and remember that oil and cake from any kind of seed is of the same vahUf it will be apparent that the yield is very different ; for example, oK»i, T 1 1QQC ( E. India linseed worth 52*. per quarter. zoth July, iSdb, ^ Petersburg Unseed 48 to 52 do. prices of seed, ^(j^^g^ ° - . 52 - - The difference of 4s. must be paid for in the quantity of oil, which at 38*. 6d. per cwt. (the then price) requires about 11^ lbs. more oil expressed to pay for the difference in the market value of the seed. Another London crusher informed me that East India linseed will produce 17 gallons, and he seemed to think that that was the extreme quan- tity that could be expressed from any seed. The average of last year's Russian seed would be about 14 galls. ; Sicilian seed 16 galls. Num- Place. Engine Power. Hydraulic Presses. Stampers. Rollers. Edge- stones. Kettles Work done, — reduced to an hour. ber of press- ings. Prance 10 horse power 1 hydrau- 5 light 1 pair 1 pr. edge- 5 table kettles 1 English 2 pres- lic, 200 stamp- rolls. stones. small size quarter per sings. tons. ers. heated by steam. working hour. London 20 horse power 1 hydrau- 13 light 1 pair 2 pr. edge- 8 table kettles 2 English 2 ditto lic, 800 stamp- roUs. stones. small size quarters per tons. ers. heated by fire. working hour. London 12 horse power, none 9 light 2 pair 2 pr. edge- 4 table kettles i English 8 ditto but the engine stamp- rolls. stones, small size quarter per is used also for ers. used used also heated by working other work. also for other purposes for other purposes. fire. hour. HuU 18 horse engine, none 3 very 1 pair 1 pr. edge- 3 double case li English 1 ditto old construc- heavy rolls. stones. large size quarter per tion. stamp- ers. steam kettles. working hour. Ditto 22 horse engine none 6 very heavy stamp- ers. 2 pair rolls. 2 pr. edge- stones. 6 double case large size steam kettles. Not known. 1 ditto 1 lb. oil. 1 lb. oil. 1 lb. oil. ** Rape-seed. — I have not turned my attention to the quantity of oil extracted from this seed ; but a French crusher (M . Geremboret), on whom I think one may place consider- ible dependance, told me that 3f lbs. of best Cambray rape-seed yielded - . - 3f — common rape-seed - - - 4| — — poppy-seed - - . . *' Rape-seed weighs from 52 to 56 lbs. per imperial bushel." The following are the heads of a reference of machinery for a seed oil-mill : — 1. Two pairs of cast-iron rollers, 19 inches long, and 10 inches in diameter, fixed in a cast-iron frame, with brasses, wheels, shafts, bolts, scrapers, hoppers, shoes, &c. 2. Two pairs of edge-stones, 7 feet diameter each, with two bottom stones, 6 feet diameter each, cast-iron upright shafts, sweepers, wheels, shafts, chairs, brasses, bolts, and scrapers, with driving spur-wheels, &,c. 3. Five steam kettles, with wheels, shafts, and brasses, bolts, breeches, and steam pipes, an upright cast-iron shaft, with chairs and brasses at each end ; and a large bevel wheel upon the bottom end of upright shaft, and another, smaller, upon fly-wheel shaft, for the first motions. OILS, VOLATILE OR ESSENTIAL. 289 4 ^^"^s:^^ ^^a^ With ,0 ^^^^^oT:^:,";:^^ «^^^^ «^- ^Veli^ell^^l manufacture 20. Oil. Cocoa-„u, irni:lf^T,T9to'o:^^^^^^^^ ^^ -re oi, O,^ Olive, imported in 1860, 20,784 tuns, in 1851, 11 488 tun^ Oil, Tra.u. Blubber, and Spermaceti, imported in 1850 2iTq u. • ,oc, tuns. For Seal Oil, see Rkal Fisiikry. ^ ' ^^'^^^ *""^ *° l^^l. 22,219 OILS, VOLATILE OR ESSENTIAL; Manufacture of Thp v^io«i -i every part of odoriferous plants, whose aroma they dSuse bMherexhLl'n^'K"'. ^" different organs of different species. Certain plait«» such II thZ! l T ' ^"* "* labiat ^*^ part an empyreumatic odor to the prS But af tL^^ua ^"^ less upon the quantity employed than iinAn t hit «r H ^ r^ "^^ ^^^""^ distilled depends obvious that by^^ivinJaSleVo'rm t^he stfl ,t^^^^^^ ^«. '^' "^^-'7^ « Hence the narrower and taller the alembic is, w thfn^ertffn \tu. T^ ^convenience, the proportion of oil relative to that of the aromX wa?er fiom Hk?' ^•*''' T^ ^ ous and vegetable matter employed. Some place the plants in^iit^^"^'''"' ""^ *^"^ immediately over the bottom of the still underihe water or Vhov^'^''^''^ '"'^^"^ ^^^^ But the best mode in my opinion is to stX«n imHaht ' r^ '^."'' '^"^^^^ »" ^^^ steam, drive down through them, s^am of any Sfsir^Zfe iu tl^n'' ^"" f '^' P^""^^' ^^ »*> further regulated by the size of the outfet orificeTeadin.. to fho'^ ?"* ^^"^P^i?^"^^ being should be made of strong copper tinned inside andTn/.l?- ,1 ^^^^^nser. The cylinder of wood, such as soft deal or sycamore. ' '^ '" ^^*^ ^^"^^ conducting specie. The distillation is to be continued as Ion" as thp w«tor «« ance. Certain plants yield so little oil by Ihe ord Wv rfr '' "^''^^ ^^ » ^'^^Y appear- care, that nothing but a distilled wa^er is obta^ned^f J 1^?'"'' "«twithstanding every be poured upon a fresh quantity of the plants in thp .liu ?'t' l^^ ^""T ^^^^'^ «^ again to be poured upon fresh plants • and thn« i f ] ' ^''»''^ ^^'"^ ^^^^^ ^^er, 19 separated. This being -iken off, the ^turat^ w.t P^-*^^^^^'' ^*" ^ '^^^^^^'^ ^^^^^ of oil'be The refrigeratory vessd is usuallv ? worr^ *' '^^'^^"^ ^«'' * ^^ distillation, whose temp?ratur7should be TeSaSv coll IftT'T^,?^"^ in a tub of water, fennel, &c., which become concfete at low Pmn.l ^'^u^^'""^ ^^^ «"^ «^ anise-seed than 45° F. ^""^ temperatures, the water should not be coolw 2 " im-mam 290 OILS, VOLATILE OR ESSENTIAL. I nr I 111! * Jil Ilili of the flask Uke the spout of a coffee-pot. The water and the oil collected in this vessel soon separate from each other, according to their respective specific gravities ; the one floating above the other. If the water be the denser, it occupies the under portion of the vessel, and continually overflows by the spout in communication with the bottom, while the lighter oil is left. When the oil is the heavier of the two, the receiver should be a large inverted cone, with a stopcock at its apex to run off the oil from the water when the separation has been completed by repose. A funnel, having a glass stopcock attached to its narrow stem, is the most convenient apparatus for freeing the oil finally from any adhering particles of water. A cotton wick dipped in the oil may also serve the same purpose by its capillary action. The less the oil is transvased the better, as a portion of it is lost at every transfer. It may occasionally be useful to cool the distilled water by surrounding it with ice, because it thus parts with more of the oil with which it is impregnated. There are a few essential oils which may be obtained by expression, from the sub- stances which contain them ; such as the oils of lemons and bergaraot, found in the pellicle of the ripe fruits of the citrus aurantium and medica ; or the orange and the citron. The oil comes out in this case with the juice of the peel, and collects upr* its surffl-CC For collecting the oils of odoriferous flowers which have no peculiar organs for impri- soning them, and therefore speedily let them exhale, such as violets, jasmine, tuberose, and hyacinth, another process must be resorted to. Alternate layers are formed of the fresh flowers, and thin cotton fleece or woollen cloth-wadding, previously soaked in a pure and inodorous fat oil. Whenever the flowers have given out all their volatile oil to the fixed oil upon the fibrous matter, they are replaced by fresh flowers in succession, till the fat oil has become saturated with the odorous particles. The cotton or wool wadding be- ing next submitted to distillation along with water, gives up the volatile oil. Perfumers alone use these oils; they employ them either mixed as above, or dissolve them out by means of alcohol. In order to extract tlie oils of certain flowers, as for instance of white liiies, infusion in a fat oil is suflicient. Essential oils differ much from each other in their physical properties. Most of them are yellow, others are colorless, red, or brown ; some again are green, and a few are blue. They have a powerful smell, more or less agreeable, which immediately after their distillation is occasionally a little rank, but becomes less so by keeping. The odor is seldom as pleasant as that of the recent plant. Their taste is acrid, irritating, and heating, or merely aromatic when they are largely diluted with water or other substances. They are not greasy to the touch, like the fat oils, but on the contrary make the skin feel Toagh. They are almost all lighter than water, only a very few falling to the bottom of this liquid; their specific gravity lies between 0*847 and 1-096; the first numbei denoting the density of oil of citron, and the second that of oil of sassafras. Although styled volatile oils, the tension of their vapor, as well as its specific heat, is much lest than that of water. The boiling point difi'ers in different kinds, but it is usually about 316* or 320® Fahr. Their vapors sometimes render reddened litmus paper blue, although Jhey contain no ammonia. When distilled by themselves, the volatile oils are partially decomposed ; and the gaseous products of the portion decomposed always carry off a little of the oil. When they are mixed with clay or sand, and exposed to a distilling heat, they are, in a great measure decomposed ; or when they are passed in vapor through a redhot tul^, combustible gases are obtained, and a brilliant porous charcoal is deposited in the tube. On the other hand, they distil readily with water, because the aqueous vapor formed at the surface of the boiling fluid carries along with it the vapor of the oil produ- ced in virtue of the tension which it possesses at the 2 1 2th degree Fahr. In the open air, ,the volatile oils burn with a shining flame, which deposites a great deal of soot. The congealing point of the essential oils varies greatly ; some do not solidify till cooled below 32°, others at this point, and some are concrete at the ordinary temperature of the atmos- phere. They comport themselves in this respect like the fat oils ; and they probably con- sist, like them, of two different oils, a solid and a fluid ; to which the names stearoptene and ekoptenej or stearessence and oleiessence, may be given. These may be separated from each other by compressing the cooled concrete oil between the folds of porous paper ; the stearessence remains as a solid upon the paper ; the oleiessence penetrates the paper, and may be recovered by distilling it along with water. When exposed to the air, the volatile oils change their color, become darker, and gradually absorb oxygen. This absorption commences whenever they are extracted from the plant containing them ; it is at first considerable, and diminishes in rapidity as it goes on. Light contributes powerfully to this action, during which the oil disengages a little carbonic acid, but much less than the oxygen absorbed ; no water is formed. The oil turns gradually thicker, loses its smell, and is transformed into a resin, which becomes eventually hard. De Saussure found that oil of lavender, recently distilled, had absorbed in four winter months, and at a temperature below 54° F., 52 times its OILS, VOLATILE OR ESSENTUL. 291 volume of oxygen, and had disengaged twice its volume of carbonic acid ca*^. „„r w. It yet completely saturated with oxveen THp Kf*.«r«oJl.7^ wtruumc acia gases; nor was its liquefying temperature, in the spfS^of two vear^ i '^ °^ amse-seed oil absorbed at and disengaled 2I times itsVolSmfoT trZ^:":uf,:'^ZV^^^^ ^ experience such an oxydizement is composed of a resin dTs'solv^ in t^pin.], L^f^ *2 the 0,1 may be separated by distilling the solution a WwTh^^t^^^^ 7wl/^ ^'^'-i*?^ an unchanged state, they must be put in vials, medtl^eZcLJZ-^l^^^'^f "* stopples, and placed in the dark. ^°P' ''^''^^ ^'^ ^"»"°d B^^ Volatile oils are little soluble in water, yet enoueh so as in ;m„-.^ « •. v their characteristic smell and taste. The water whkh distL w.T«l I^-^^ ^'^*'°^ a saturated solution of it, and as such is used in medicine u^dpr ti^ """^ '' !?F"."^ water. It often contains ither volatile substances Tonta^I'd in the lH^' 'J ^'"''^^"^ apt to putrefy and acquire a nauseous smeU when kept in nerfertlv nn?C^ 1' f ^"^ ^^l"""^ '^ vessels partially open, these parts exhale, and the water 'remaps sweet ¥l?' ^T ^ however, which are made by agitating volatile oU with simnlf distill J wL ^ '^*^^"' to spoil by keeping in well-corked bottles. ^ ''^"^^ ^*^^'' "« >»ot apt The volatile oils are soluble in alcohol, and the morp sn ti.« o#.^ Some volatile oils, devoid of oxygen, such as the ofls of ^»^P«rn "/^ ^^^ 'P^^* «• sparingly soluble in dOute alcohol ; while the ol of lavendernennp/ """^"^ "" ^^^ bly so. De Saussure has inferred from his experiments that thfl^^^^ *'^ considera- soluble in alcohol, the more oxygen they coS Such cn-^^ volatile oils are the more ous spirits which the perfumers incoiTectircalTwatertsZ^T''"/ '^"^ **!f ^°""'"- eau '^'T' «^»>^^^«°^ of capiv, and exposing it to heat. A di^ ess^ntmTnii I ^""'".^ * ^™P «^ ^^^ «»1 «» P^Per, Whilst Z oil mix^ wUh anv oT thP Thnv!^ oil evaporates without leaving any residu,^^ paper. If fat oU beTresent^ it wUl remlfn'"^-^"?' l^^""^ * translucent stain uiK,n tS Ual oil with thrice its vnlnml !!rT • vT" ""^^^^olved, on mixing the adulterated essen- mixed with vSe oil ie^si'v of specific gravity 0-840. Resinous matter ^^^^irlsZbles H^^^^^^^^ the presence of a cheap essenti;i oil in a dear one, the suspectZa :;e t^b^ pour^^ uCn a"b^ 0?".^ ^T^' ^"''^- ^ ^'^ <*-p'' ^ and smelled to from time to tZe Tthfc ^^^' '^^'^^.^" ^° ^^ ^^^'^^^ i» the air, of the oil which exhaks at th. k.„?" •^'' "^^J "^^ may succeed in distinguishing the odo^ which serves perfectlv to dp p.. ? r"!"^' ^"^ ^^^' '^^'''^ ^^^^^^ »t the end; a meUlS when the deba'sX^'is mlf^'wUhtS^^^^^ '" I'' ^"" ^^^"^'^^ ''^'' Mo~ remains in a great me^suTe u1d7s olveT I? aro^ '^^ ^'.l^'^^^^ '^' «'^ «^ '^'^^^'^^^ than water, be mixed thev mo v Ko J , u '^ ^^^^'^^ ^^^" ^^^er, and an oil lighter and then leaving the mfcat^est ^^r'"^.**! T*''^" ^ ^'"^ ''^^ "^'^'^ that liquiS^ ful examination V thrje'pVctiv^dens^Uer ''' "^'^'^'^ be distinguished by o c\t^ bland oil hafbe"^^^^^^^ f ^^ "^ ^'^ '/"^^ ^^^"'^ ^-^^^ ^-^ whicu .he steam, as it passes up^Ihrou J^the hrli"; ^' ''T' °^ '^f'"*" ''''^^ ^'^hin the still. The and condenses along with it in the worm Th ^7'"^^^".' '^"^^^ ^"'^t^ ^^^^^ile oil, falls to the bottom of the water hasTo ^;n. ^ °j' '''^'''^ ^^' ^^'"^^ ^^e'"' «"d which tke cyanogen gas than hvdrocy^nror nr.?^^"^ ^f Penetrating a smell, that it is more It is heavier than waterrwhirmuch dilnJpd^'-^'K ^^'' "" ^^' * ^«»^^" y^»°^ <=o^^ burnin. taste. When ex^sed ?o The air h Ik k^^' ^" agreeable smell, and a bitte; tals of benzoic acid. ThiVoiT consist A^* f'^^ ''/^^^'^* *"^ ^^ts fall a heap of crys- contains hydrocyanic acid, aid ?sSnn.* "^'T'^ f^"^"" *^"^5 one of which is volatUe, acia, and is poisonous ; the other is less volatile, is not poisonou^ u t. 292 OILS, VOLATILE OR ESSENTIAL. OILS, VOLATILE OR ESSENTIAL. I iii'^ absorbs oxygen, and becomes benzoic acid. If we dissolve 100 parts of the oil of bitter almonds in spirit of wine, mix with the solution an alcoholic solution of potash, and then precipitate the oil with water, we shall obtain a quantity of cyanide of pot- ash, capable of producing 22^ parts of prussian blue. Oil of bitter almonds combines with the alkalis. Perfumers employ a great quantity of this oil in scenting their soa|>8. One manufacturer in Paris is said to prepare annually 8 cwt of this oil. A similai poisonous oil is obtained by distilling the following substances with water: the leaves of the peach {amygdalus persica), the leaves of the bay-laurel (prunw lauro-cerams), the bark of the plum tree {prunus padns), and the bruised kernels of cherry and plum- stones. All these oils contain hydrocyanic acid, which renders them poisonous, and they also generate benzoic acid, by absorbing oxygen on exposure to air. Oil of bitter almonds, in the crude state, consists of hydruret of benzoyle, hydrocyanic acid, benzoic acid, and benzoine. The two first constituents are essential ones ; the othew being accidental, and the result of spontaneous reactions. The hydruret of benzoyl when pure is colourless, transparent, of spec. grav. 1 -043 ; and though it possesses the almond flavour, is not poisonous ; it ought to form 85 to 90 per cent in volume of the crude oil When oil of vitriol is mixed with that essential oil, it merely gives it a dark reddish brown colour, but does not decompose it. If the said hydruret, however, be exposed to the air, it becomes oxidized, and by the substitution ot one atom of oxygen for one of hydrogen, it is transformed into benzoic acid ; a com- pound often present in oil of bitter almonds. This acid is not coloured by oil of vitriol Benzoine when present, however, forms a violet coloured compound with sulphuric acid. Hydrocyanic acid sometimes is present to the extent of 8 or 10 per cent, in crude oil of bitter almonds, rendering the mixture poisonous. To detect alcohol in oil of bitter almonds, nitric acid of specific gravity 1*42 may be employed, as I did in testing for alcohol in wood spirit.* If the oil be free from alcohol, no immediate action occurs, but in the courae of 3 or 4 days crystals of benzoic acid begin to appear, and eventually occupy the whole bulk, giving a bright emerald green colour : this quiet reaction is very characteristic. But if alcohol to the amount of 8 or 10 per cent, be present, a violent eflfervescence ensues in a few minutes after pouring in the nitric acid, with the disengagement of nitrous fumes. By using nitric acid of 1*5 a very small proportion of alcohol may be recognized. Essential oil of bitter almonds, free from adulteration, should have a specific gravity at most of 1*52. When the crude oil of bitter almonds, and a mixture of milk of lime and protochlo- ride of iron are all agitated together, and subjected to distillation at a gentle heat, the product is an oil of bitter almonds free from hydrocyanic acid. OU estential of bitter almonds. To determine whether the pure oil of bitter almonds, (hydruret of benzoyle) be poisonous or not, Mr. G. D. Grindley, of the Pharmaceutical school, made the following researches. He at first adopted the usual plan for removing the hydrocyanic acid, by distilling the commercial oil of almonds with a mixture of proto- chloride of iron and lime ; the product was still contaminated with the acid, and several repetitions, conducted with every precaution, were attended with no better success. He then adopted, by the suggestion of Professor Redwood, the following method, which proved most satisfactory. The oil was mixed with an equal quantity of water, and digested in a water bath with red oxide of mercury, and small quantities of lime and protochloride of iron ; time having been allowed for the decomposition of the acid the whole was introduced into a copper retort on account of the jumpmgs during distillation. The product consisted of pure hydruret of benzoyle, while bicyanide of mercury, benzoate of lime, chloride of calcium, and oxide of iron, remained in the retort, with benzoyne and an excess of the ingredients employed. The process is founded upon the strong affinity which exists between mercury and cyanogen, so that when binoxide of mercury and hydrocyanic acid are digested together, they are decomposed, bycanide of mercury and water being formed- The protochloride ot iron, which with the lime yields pro- toxide, is introduced to prevent the formation of benzoic acid from the oxidation of the oiL For the same reason care should be taken to conduct the process with as little access of air as possible. The oil thus procured was pure and colourless. No trace of nitrogen could be detected by Lassaigne's test, which he found to be exceedingly delicate, affording indications of the presence of that body in extremely minute quantities of morphia, narcotine, Ac. This test consists, in adding to a very small quantity of the substance to be tested, in a small German glass tube, a fragment of potassium about the size of a millet seed, and heating the tube over the fiame of a spirit lamp, till the organic substance is entirely carbonized. The carbonaceous residue is treated with cold water, and to the clear decanted liquor a drop of a solution containing the mixed two oxides of iron is added. A dirty green precipitate is immediately formed, which if nitro- * See the pamphlet, Rtvtttue i» Jeopardf. 293 fcTd^^irpure ^Wi",""' >r^^i ^.'"^' t".*^« '^^'^'^^^ of a drop of hydrochloric health or pfrl ltte.^trd"o^l"Ll b'^^V"^ without injurious^ffec^t on thSJ of Messrs. Ked wood and Cu^Zey ^« always purified by this valuable proceaa It concretes in I^it?™,^ "'J^'^l l^^^'eT^'"' 7f ^^ ^^^^ «^^^« ^^' heated to 64° nearly. ltsl,e<^fif ^li^^^l%%,^' ^^^ ^ »% -^^^ again till S 1^ 'J'J'^J^l^^oponions in alcohol of 0-806; but only to the extent JrVo^^* . ^- "^ f^^ hoi of 0-84. When it becomes resinous by long expos^e trth. Jr ^? T ""T' '" ^^ ing properly. It consists of two oils ; a solid stearessen^e ln<^ « r '-i' ''?^' '^ ''''''^^^' may be separated by compression of the cold concrete oh' "^ oleiessence, which Uu of bergamot is extracted by pressure from the rind nf tho ,.v r -. ^ . . hergamium and aurarUium. It is a limpid, yellowish flu dhavJncf ^"^ n "'* ""^ *^^ "^"^ of oranges. Its specific gravity varies from oS to C^^5^^^^^^^^ resembling that cooled a little below 32°. * '^ b-comes concrete when OUofcajeput is prepared in the Moluccas, by distillin*' the drv u^rr^ r *i. leucadendron. Cajeput is a native word, si Jifyinf m^^^^^^^^ themelaleuca green ; it has a burning taste, a strong smell of camnhSrtfrtnT^'^^ ^T' T^'^ °" " very fluid, and at 48o has a specific gravi^of 0-9^ Thp . i^ ^'"^' *"? '^'^^"^- ^^ " the copper vessels in which it is imported so thnV?; -J ^^^o'" seems to be derived from which also separates the oil ntoTwrsom'^L^e fi /^^^^^^ ^' ^^^^'"f '°^ ^^^^ ^^'^> cf 0^897, the last of 0-920. This hasT^r^en color '''^'' ^'^^^"^ * ^^""'^^ the aiminum cyminnm (cumin) afford an Sfl simn«?t fif ^'^'''^ '^ ^'^^- *"»« se^s of Its specific gravity is 0-975 ""'^" ^"^ the preceding, but not so agreeable. ounce of oil of lemons be added to 3 rund, of ^hi^'f ^k"""^" ^^ "'^"^"°'^^- ^^ « readily from the adhering water ^ ' ""^ ^^'^ '''^' ^^^^ "^^^ it separate more the^MowJng ^lantsTSn fhaltE j:l:!!:^?T:i}'^^ ^^^^^^ ^^ ^^^^^ and those of iilfoil (achilLamSH^^ThT^ »t''"^' ^^^ ^°^^" of arnica rmmtarl Oil of cinnamon is extraTt^T di. hL" r ^^'* ^\* T""' ^'^''' ^^ 0-852. ^ It is i^oduced chieflVrcl^on'^trt^^^^^^^ of'^ba^k'V/fi/f' ''"""^ cinnamomun. distilled over with difficultv and th^ «.«« pieces oi bark unfit for exportation. It is and the use of a low st^^ It his atTst a 'Lr^n"^ by/he addition of salt wate^ with age. It possesses in a h gh de^ee St^^^^^^^ ' •^°'' ^"' '' ^^^«°^^« ^r«^« smell of cinnamon. It is he^v^er thfnl.«/ •! ^^^^^t burning taste, and the agreeable cretes below 32° F., anrdoesTot fuse a^^^^ %T"\^'. ^^^1'^ ^^^°^ ^'^^^' It con! soluble in water, and when a^ut J with k Ld\ '^'^ '** ^[' ^' '' ^^^ sP»"ngly abundantly in alcohol, and comwiTs with ammonk into'T'" ' '^' ''^''' ^' ^'^^^'^^-' on exposure to air. "^ ammonia into a viscid mass, not decomposed regZrcollr'ss'or^ydW^^^^ a stearessence in large gentle heat into a colorlesi iS whth .r^?^r^ pulverized, and which melt at a very mediate between thatTf cinnamon^ nd f ^^ f "»^«^«» 'tooling. It has an odor inter^ wards bm.in, and arLatfc"" 1^^,! be^^e^^^^ T\^' ^''' ^'^-^y> ^-^ -^el .ctt?%f if ilUl'ofy'eS^^ ?" 1"^ «°^" ^l^^^of the caryopkyUus aromat. taste. Its specific gmvity fs Tofi i I • "^''^^^^/^ell of the cloves, and a burnin- difficult to distil. A^t thfend of a certain t^me^t d'/ ''! ^'^' ^^^^^"^ ^"^> ^^^ ^he most similar stearessence is obtained bv Sn^ \T I °^Pf ^^^s a crystalline concrete oil. A solution cool. The crystals thSs f^^^^^ ar/h -1^ '^^ ' ^'" "^*^«^«'> ^"^ '^tling thi out taste and smell. Oil of cloveSlem^rW .^"l"' "^^'^f' §^'^"P^ ^» ^»«t>»J«^' ^'ith- alcohol, ether, and acetic acid It d^f J^f '^^|M?^^^^'°'<^^ properties. It dissolves in even when exposed to that cold for ^t. ° i f^'^'^^ ^\^ temperature of 4° under (y> F.. green, then brown, and turns resinous Ntr''''"'-:i ^\ ""^^'^^ ^^'*^""e gas, becomes converts it into oxalic acid. If mix^ w d T^ """^^^ '^ '^' *"<^ »^ Sealed upon it, sulphuric acid, an acid liquor is fomed at wL^'oI Sff ^' "^''^ ?"%*^^'? "^ ''' ""'''^^^ oC urmea, at whose bottom a resm of a fine purple color is iH - m 3^4 OILS. VOLATILE OR ESSENTIAL. found After being washed, this resin becomes hard and brittle. Alcohol dissolves it, and tkket a red color ; and water precipitates it of a blood red hue. It dissolves also m ether When we agitate a mixture of strong caustic soda ley and oil of cloves in equal ^rts;the mass thickens very soon, and forms delicate lamellar crystals. If ^^^^^^^P^"; water upon it, and distil, there passes along with the water, a small quantity of an oil which differs from oil of cloves both in taste and chemical properties. ,P"""f *J«-^*;.°*; ine the liquor left in the retort lets fall a quantity of crystalline needles, which being separated by expression from the alkaline liquid, are ^Imost inodorous, but possess an alkaline taste, joined to the burning taste of the oil. These crystals '^fl"i'^e/«r^sduli°^ from 10 to 12 parts of cold water. Potash ley produces similar effects. Ammonmcal ^8 transmitted through the oil is absorbed and makes it thick. The concrete combina- Son thus formed remains solid as Ion- as the vial containing it is corked, but when open- ed, the compound becomes liquid ; and these phenoniena may be reproduced as many times as we pleasV^ Such combinations are decomposed by acids, and the oil set at liberty has SJe same taste and smell as at first, but it has a deep red color. The alkalis enable us to detect the presence of other oils, as that of turpentine or sassafras, i^/hat of cloves because they fix the latter, while the former may be volatilized with water by distilling the mixture. The oil of cloves found in commerce is not pure, but contains a mixture of the tincture of pinks or clove-gillyflowers, whose acrid resin is thereby introduced. U is sometimes sophisticated with other oils. The oil of elder is extracted by distillation from the flowers of the satnbucw nigra. It has the consistence of butter. The watery solution is used in medicine. Oil of fennel is extracted by distillation from the seeds of the anethum fms a soap so uble in 60 parts of water It is absorbed by wood charcoal, and still better by bone black ; whereby it may be corn- pletely abstractii from bad whiskey. According to Buchner, another oil ^^y also be ob- teined from the residuum of the second distillation of whiskey if saturated with sea salt and again distilled. Thus we obtain a pale yellow fluid oil, whicli does not concrete wilh cold, possessed of a disagreeable smeU and acrid taste. Its specific gravity is 0-835. It is soluble in alcohol and ether. ,.^ ^ . ,.^ . 2. The oil from potato spirits has properties quite different from the preceding. t IS obtained inconsiderable quantity by continuing the distillation a^^^^^^/^ ^f, ^*|f .**" cohol has come over, and it appears in the form of a yellowish oil, mixed with water and spirits. After being agitated first with water, then with a strong solution of mu- riate of lime, and distilled afresh, it possesses the following properties ; it is colorless limpid, has a peculiar smell, and a bitter hot taste of considerable permanence. It leaves no greasy stain upon paper, remains liquid at 0° F., but cooled below that point t crysrallizes Uke oil of anise-seed. When pm-e it boils at 257° F.; but at a lower degree, if it contains alcohol. Its specific gravity is 0-821, or 0-823 when it contains a little water. It burns wilh a clear flame without smoke, but it easily goes out, il not burned with a wick. It dissolves in smaU quantity in water, to which it imparts us taste and the properties of forming a lather by agitation. It dissolves m all proportions in alcohol. Chlorine renders it green. Concentrated sulphuric acid converts it into a crimson solution, from which it is precipitated yellow by water. It dissolves m all pro- Dortions in acetic acid. Concentrated caustic leys dissolve it, but give it up to water. 11 does not appear to be poisonous, like the oil of corn spirits; because, when given by spoonfuls to dogs, it produced no other effect but vomiting. OILS, VOLATILE OR ESSENTIAL. 295 3. The oil of brandy or grape spirits is obtained during the distillation of the fermented residuum of expressed grapes ; being produced immediately after the spirituous liquor has passed over. It is very fluid, limpid, of a penetrating odor, and an acrid disagree- able taste. It grows soon yellow in the air. When this oil is distilled, the first portions of it pass unchanged, but afterwards it is decomposed and becomes empyreumatic. It dis- solves in 1000 parts of water, and communicates to it its peculiar taste and smell. One drop of it is capable of giving a disagreeable flavor to ten old English gallons of spirits. It combines with the caustic alkalis, and dissolves sulphur. Oil of jumper is obtained by distilling juniper berries along with water. These should be bruised, because their oil is contained in small sacs or reservoirs, which must be laid open before the oil can escape. It is limpid and colorless, or sometimes of a faint greenish yellow color. Its specific gravity is 0-911. It has the smell and taste of the juniper. Water, or even alcohol, dissolves very little of it. Gin contains a very minnte quantity of this oil. Like oil of turpentine, it imparts to the urine of persons who swallow it, the smell of violets. Oil of juniper is frequently sophisticated with oil of turpentine introduced into the still with the berries ; a fraud easily detected by the diminished den- =8ity of the mixture. The oil of lavender is extracted from the flowering spike of the lavandula spica. It is yellow, very fluid, has a strong odor of the lavender, and a burning taste. The specific gravity of the oil found in commerce is 0-898 at the temperature of 72° F., and of 0-877 when it has been rectified. It is soluble in all proportions in alcohol of 0-830, but alcohol of 0-887 dissolves only 42 per cent, of its weight. The fresh oil detonates slightly when mixed with iodine, with the production of a yellow cloud. There occurs in commerce a kind of oil of lavender known under the name o< oil of a«;nc or oil of spike, extracted by distillation from a wild variety of the lavandula spica, which has large leaves, and is therefore called latifolia. This oil is manufactured in the south of Europe. Its odor is less characteristic than that of the lavender, resembling somewhat that of oil of turpentine, with which it is indeed often adulterated. It is also so cheap as to be sometimes used instead of the latter oil. Oil of lavender deposites, when partially ' exposed to the air, a concrete oil, which resembles camphor, to the amount of one fourth of its weight. Oil of lemons is extracted by pressure from the yellow peel of the fruit of the lemon, or ntrus medica. In this state it is a yellowish fluid, having a specific gravity of 0*8517 ; but when distilled along with water till three fifths of the oil have come over, it is ob tained in a colorless state, and of a specific gravity of 0-847 at 72° F. This oil does aol become concrete till cooled to 4° below 0^ F. The oil of lemons has a very agreeable smell of the fruit, which is injured by distilla- tion. It is soluble in all proportions in anhydrous alcohol, but only 14 parts dissolve in 100 of spirits of wine of specific gravity 0-837. This oil, especially when distilled, forms with muriatic acid similar camphorated compounds with oil of turpentine, absorbing no less than 280 volumes of the acid gas. Oil of lemons kept long, in ill-corked bottles, generates a quantity of stearessence, which when dissolved in alcohol, precipitated by w4ter, and evaporated, affords brilliant, colorless, transparent needles. Some acetic acid is also generated in the old oil. Accord ing to Brandes, the specific gravity of oil of lemons is 0-8786. The oil of mace lets fall, after a certain time, a concrete oil under the form of a crys- talline crust, called by John myristicine. The oil of nutmegs is extracted chiefly from mace, which is the inner epidermis of these nuts. It is colorless, or yellowish, a little viscid with a strong aromatic odor of nutmegs, an acrid taste, and a specific gravity of 0-948. Il consists of two oils, which may be easily separated from each other by agitation with water; for one of them, which is more volatile and aromatic, comes to the surface, while the other, which is denser, white, and of a buttery consistence, falls to the bottom. The latter liquefies by the heat of the hand. The oil of orange flowers, called neroli, is extracted from the fresh flowers of the ctYnw aurarUium. When recently prepared it is yellow ; but when exposed for two hours to the rays of the sun, or for a longer time to diffuse daylight, it becomes of a vellowish- red. It IS very fluid, lighter than water, and has a most agreeable smell. The aqueous solution known under the name of orange-flower water, is used as a perfume. It is obtained either by dissolving the oil in water, or by distilling with water the leaves cither fresh or salted ; the first being the stronger, but the last being the more fragrant prepar- ation. Orange-flower water obtained by distillation, contains besides the oil, a principle twhich comes over with it, of a nature hitherto unknown ; it possesses the property of im- parting to water the faculty of becoming red with a few drops of sulphuric acid. The water formed from the oil alone, is destitute of this property. The intensity of the rose- color IS a test m some measure of the richness of the water in oil. The oil of parsley is extracted from the apium petroselinum. It is of a pale yellow 296 OILS, VOLATir.E OR ESSENTIAL. OILS, VOLATILE OR ESSENTIAL. S07 • ?i \i\ color, having the smell of the plant, and consists of two oils separable by agitation in water. Its liquid part floats upon the surface in a very fluid form ; its stearessence, which falls to the bottom, is butyraceous and crystallizes at a low temperature. This concrete oil melts at 86° F. The oil of pepper is extracted from the piper nigrum. In the recent stale it is limpid and colorless, but by keeping it becomes yellow. It swims upon the surface of water. In odor it resembles pepper, but is devoid of its hot taste. The oil of peppermint is extracted from the meniha piperita. It is yellowish, and endued with a very acrid burning taste. Its specific gravity is 0-920. At 6° or 7° below 0° F., it deposites small capillary cr\'stals. After long keeping it aflbrds a stearessence resem- bling camphor, provided the oil had been obtained from the dry plant gathered in flower, but not from distillation of the fresh plant. When artificially cooled, it yields 6 per cent, of stearessence, which crystallizes in prisms with three sides, has an acrid, somewhat rank taste, is soluble in ether and alcohol, and is thrown down from the latter solution by water in the form of a white powder. Peppermint water is characterized by the sensation of coolness which it diffuses in the mouth. The oil of pimento is extracted from the envelopes of the fruits of the myrius pimenta, which afford 8 per cent, of it. It is yellowish, almost colorless, of a smell analogous to that of cloves, an acrid burning taste, and a specific gravity greater than water. Nitric acid makes it first red, and after the effervescence, of a rusty brown hue. It combines with the salifiable bases, like oil of cloves. The oil of rhodium is extracted from the wood of the convolvolus scoparius. It is very fluid, and has a yellow color, which in time becomes red. It has somewhat of the rose odor, and is used to adulterate the genuine otto. Its taste is bitter and aromatic, which it imparts to the otto as well as its fluidity. The oil of roses, called also the attar or otto, is extracted by distillation from the petals of the rosa centifoUa and sempervirens. Our native roses furnish such small quantities of the oil, that they are not worth distilling for the purpose. The best way of operating is to return the distilled water repeatedly upon fresh petals, and eventually to cool the saturated water with ice ; whereby a little butyraceous oil is deposited. But the oil thus obtained has not a very agreeable odor, being injured by the action of the air in »he r-peated distillations. In the East Indies, the altar is obtained by stratifying rose leaves in earthen pans in alternate layers, with the oleiferous seeds of a species of digi- talis, called gengeliy for several days, in a cool situation. The fat oil of the seed absorbs the essential oil of the rose. By repeating this process with fresh leaves and the same seed, this becomes eventually swollen, and being then expressed furnishes the oil. The turbid liquid thus obtained is left at rest, in well-closed vessels, where it gets clarified. The layer of oil that floats on the top is then drawn off" by a capillary cotton wick, and subjected to distillation along with water, whereby the volatile otto is separated from the fat seed-oil. The oil of roses is colorless, and possesses the smell of roses, which is not however agreeable, unless when diff'used, for in its concentrated state it is far from pleasant to the nostrils, and is apt to occasion headaches. Its taste is bland and sweetish. It is lighter than water, and at the temperature of 92^, its specific gravity compared to that of water at 60** is 0-832. At lower temperatures it becomes concrete and butyraceous ; and after- wards fuses at 90°. It is but slightly soluble in alcohol ; 1000 parts of this liquid at 0-806 dissolving only 7| parts at 58° F. This oil consists of two parts, the stearessence and oleiessence ; the latter being the more volatile odoriferous po>!ion. The oil of rosemary is extracted from the rosmarinus officialis. It is as \im\ d as water, has the smell of the plant, and in other respects resembles oil of turpentine. The oil found in commerce has a specific gravity of 0-911, which becomes 0-8886 by rectification. It boils at 320° F. (occasionally at 329°). It is soluble in all portions in alcohol of 0830. When kept in imperfectly closed vessels, it deposites a stearessence vo the amount of one tenth of its weight, resembling camphor. It is sometimes adulterated with oil of turpen- tine, a fraud easily detected by adding anhydrous alcohol, which dissolves only the oil of rosemary. The oil of saffron is extracted from the stigmata of the crocus sativus. It is yellow, very fluid, falls to the bottom of water, diffuses the penetrating odor of the plant, and has an acrid and bitter taste. It is narcotic. The oil of sassafras is extracted from the woody root of the laurus sassafras. It is colorless, but at the end of a certain time it becomes yellow or red. It has a peculiar, sweetish, pretty agreeable, but somewhat burning taste. Its specific gravity is 1-094. According to Bonastre, this oil separates by agitation with water into an oil lighter and an oil heavier than this fluid. When long kept, it deposites a stearessence in transparent and colorless crystals, which have the smell and taste of the liquid oil. The oil of savine is extracted from the leaves of the juniperus sabina. It is limpid, and has the odor and taste of the plant, which is one more productive of volatile oil than any other. The oil of tansy has a specific gravity of 0-946, the penetrating odor of the tanacetum vulgare, with an acrid and bitter taste. Oil of turpentine, commonly called essence of turpentine. It is extracted from several species of turpentine, a semi-liquid resinous substance which exudes from certain trees of the pine tribe, and is obtained by distilling the resin along with water. This oil is the cheapest of all the volatile species, and, as commonly sold, contains a little resin, from which it may be freed by re-distillation with water. It is colorless, limpid, very fluid, and has a very peculiar smell. Its specific gravity at 60° is 0-872 ; that of the spirit on sale in the shops is 0-876. This oil always reddens litmus paper, because it con- tains a little succinic acid. 100 parts of spirits of wine, of specific gravity 0-84, dissolve only 13| of oil of turpen- tine at 72° F. When agitated with alcohol at 0-830 the oil retains afterwards one fifth of its bulk of the spirit ; hence this proposed method for purifying oil of turpentine is defective. The oil, if left during four months in contact with air, is capable of absorbing 20 times its bulk of oxygen gas. One volume of rectified oil of turpentine absorbs at the temperature of 72°, and under the common atmospheric pressure, 163 times its vol- ume of muriatic acid gas, provided the vessel be kept cool with ice. This mixture being allowed to repose for 24 hours, produces out of the oil from 26 to 47 per cent, of a white crystalline substance, which subsides to the bottom of a brown, smoking, translucent liquor. Others say that 100 parts of oil of turpentine yield 110 of this crystalline matter, which was called by Kind, its discoverer, artificial camphor, from its resemblance in smell and appearance to this substance. Both the solid and the liquid are combina- tions of muriatic acid and oil of turpentine; indicating the existence of a stearine and an oleine in the latter substance. The liquid compound is lighter than water, and is not decomposed by it, nor does it furnish any more solid matter when more muriatic gas is passed through it. The solid compound, after being washed first with water containing a little carbonate of soda, then with pure water, and finally purified by sublimation with some chalk, lime, ashes, or charcoal, appears as a white, translucent, crj'slalline bodv, in the form of flexible, tenacious needles. It swims upon the surface of water, diff'uses a faint smell of camphor, commonly mixed with that of oil of turpentine, and has rather an aromatic than a camphorated taste. It does not redden litmus paper. Water dissolves a very minute quantity; but cold alcohol of 0-806 dissolves fully one thiid ol its weight, and Lot much more, depositing, as it cools, this excess in the form of crystals. The solution is not precipitated by nitrate of silver, which shows that the nature of the muriatic acid is perfectly masked by the combination. It is composed, in 100 parts, of 76-4 cartwn, 9-6 hydrogen, and 14 muriatic acid. The muriatic acid, or chlorine, may be separated by distilling an alcoholic solution of the artificial camphor 12 or 14 times in succession M'ilh slaked lime. Oil of turpentine is best preserved in casks enclosed within others, with water between the two. Its principal use is for making varnishes, and as a remedy for the tape-worm. The oil of thyme is extracted from the thymus serpyUum. It is reddish yellow, has an agreeable smell, and, after being long kept, it lets fall a crystalline stearessence. It is used merely as a perfume. The oil of wormwood is extracted from the artemisia absinthium. It is yellow, or sometimes green, and possesses the odor of the plant. Its taste resembles that of wormwood, but without its bitterness. Its specific gravity is 0-9703, according to Brisson, and 0-9725, according to Brandes. It detonates with iodine when it is fresh. Treated with nitric acid of 1-25 specific gravity, it becomes first blue, and after some lime brown. The numerous uses of unctuous oils give importance to their preparation, as articles of food, or for burning m lamps, and for the manufacture of soaps, Ac. The seeds most productive of oil are those of colza (a species of cabbage, brassica arve7i^s\ rape, mustard, sesamum, poppy, linseed, hemp, and beech mast. Nuts afford an oS that 18 much esteemed for certain purposes, and may be easily obtained by pressure. The following Table indicates the quantities of oil which can le extracted from diff-er- ent fruits, and some other substances : — Vol. IL 2Q 298 OILS, iTOLATILS OR ESSENTIAL. 100 Parti of each Walnuts - - - Castor-oil seeds Hazel-nuts ... Garden cress seed - Sweet almonds Bitter almonds Poppy-seeds - - . Oily radish seed Sesamum (jugoline) Lime-tree seeds Cabbage-seed White mustard r- Rape, colewort, and Swe- dish turnip seeds - Plum kernels . . Colza-seed Rape-seed - . - Euphorbium (spurge seed) Oil per Cent. 40 to 70 62 60 66 to 58 40 to 54 28 to 46 56 to 63 50 60 48 30 to 39 36 to 38 33-5 33-3 36 to 40 30 to 36 30 100 Parts of each. acanihe, or Wild mustard seed - Camelina-jieed Weld -seed Gourd-seed « Lemon-seed - Onocardium bear's foot Hemp-seed Linseed - - - . Black mustard seed Beechmast - . . Sunflower-seeds Stramonium, or thorn- apple-seeds Grape-stones - Horse chestnuts St. Julian plum Oil per Cent. 30 28 29 to 36 25 25 25 14 to 25 11 to 22 15 15 to 17 15 15 14 to 22 1-2 to 8 18 To obtain the above proportions of oil, the fruits must be all of good quality, deprived of their pods, coats, or involucra, and of all the parts destitute of oil, which also must be extracted in the best manner. The following table is given by M. Dumas, as exhibiting the practical results of the French seed oil manufacturers : — Weight per Hectolitre. Produce in Litres. Summer colza Winter colza - , - Rape-seed Camelina-seed ... Poppy-seed ... Madia Sativa - - - Beechmast ... Hemp-seed ... Linseed .... Stripped walnuts ... Sweet almonds - Olives - . 54 to 65 kilogs. 56 to 70 — 65 to 68 — 63 to 60 — 64 to 62 — 40 to 60 — 42 to 50 — 42 to 50 — By sample, 67. From 100 kilogs. — 100 — — 100 — 21 to 25 25 to 28 23 to 26 20 to 24 22 to 25 12 to 15 12 to 15 12 to 15 10 to 12 46 to 50 44 to 48 10 to 12 Colza, rape-seed, and cameline oils are employed for lamps; poppy, madia sativa^ are employed, when recent, as articles of food— or for soaps and paintings; hemp-seed and linseed for painting, soft soaps, and for printers' ink ; walnut oil, for food, painting, and lamps ; olive oil, for food, soaps, lamps. In extracting oil from seeds, two processes are required — 1st, trituration ; 2d, expres" tion ; and the steps are as follows : — 1. Bruising under revolving heavy-edge millstones, in a circular bed, or trough of iron, bedd<;d on granite. 2. Heating of the bruised seeds, by the heat either of a naked fire or of steam. 3. First pressure or crushing of the seeds, either by wedges, screw, or hydraulic preaeea. 4. Second crushing of the seed cakes of the first pressure. 5. Heating the bruised cakes ; and 6. A final crushing. The seeds are now very generally crushed, first of all between two iron cylinders revolving in opposite directions, and fed in from a hopper above them ; after which they yield more completely to the triturating action of the edge stones, which are usually hooped round with a massive iron ring. A pair of edge millstones of about 7 or 7| feet in diameter, and 25 or 26 inches thick, weighing ft-om 7 to 8 tons, can crush, in 12 hours, from 2J to 3 tons of seeds. The edge-millstones serve not merely to grind the seeds at first, but to triturate the cakes after they have been crushed in the press. Old dry seeds sometimes require to be sprinkled with a little water to make the oil come more freely away ; but this practice requires great care. The apparatus for heating the bruised seeas consists usually of cast iron or copper OIL MANUFACTURE. S99 pans, with stirrers moved by machinery. Figa. 1016 1017 1018 1019 represent the heaters by naked fire, as mounted in Messrs. Maudsley and Field's excellent seed crushing mills, on the wedge or Dutch plan. J^tg. lOieis an elevation, or side view of the fireplace of a naked heater; /g.l017 is a plan, in the line UU of Jig. 1016 Fig. 1018 is an elevation and section parallel to the line VV of Jig. 1017 Fig. 1019 is a plan of the furnace, taken above the gratp of the fireplace. -^^ " '■ " ^ I 1019 A, fireplace shut at top by the cast-iron plate B ; called the fireplate. C, iron ring-pan, resting on the plate B, for holding the seeds ,• which is kept ia its , >lace by the pins or bolts a. o i 4. « D, funnels, britchen, into which by pulUng the ring.«ase c, by the handles b, b, the se^ are made to fall, from which they pass into bags suspended to the hooks c. :^?' 1018 the stirrer which prevents the seeds from being burned by contmued contact with the hot plate. It is attached by a turning-joint to the collar F, wliich turns with the shaft G, and slides up and down upon it. H, a bevel wheel, in ^ear with the bevel wheel I, and giving motion to the shaft G. K, a lever for lifting up the agitator or stirrer E. «, a catch for holding up the lever K, when it has been raised to a proper height. 300 OILS, ADULTERATION OF Fig. 1020 front elevation of the wedge seed-crushing machine, or wedgc-presa. Fig. 1021 section, in the line XX, of Jig. 1022. 1021 y ^020 y Fig. 1022 horizontal section, in the line YY, of ^g. 1021. if'iit 1022 A, A, Upright guides, or frame-work of wood. B, B, Side guide-rails. D, Driving stamper of wood which presses out the oil ; C, spring stamper, ir re- Diving wedge to permit the bag to be taken out when sufficiently pressed. E is the lifting shaft" having rollers, 6, 6, 6, 6, fig- 1021 which lift the stampers by the cams, fl, o. Jig. 1021. F, is the shaft from the power-engine, on which the lifters are fixed. G, is the cast iron press-box, in which the bags of seed are placed for pressure, later- ally by the force of the wedge. 0, Jig*. 1019 and 1023 the spring, or relieving wedge. «, lighter rail ; d, lifting-rope to ditto. /» /> /f ff flooring overhead. OILS, ADULTERATION OF. 301 1023 g, Jigs. 1019and 1023 ;the back iron, or end-plate minutely perforated. hy the horse-hair bags (called hairs), containing the flannel bag, charged with seed j if the dam-block ; m, the spring wedge. ftg. 1022 A, upright guides; C, and D, spring and driving stampers; E, lifting roller; F, lifting shaft; a, a, cams of stampers. Fig. 1023 a view of one set of the wedge-boxes, or presses ; supposing the front of them to be removed. i^ig. 1023; o, driving wedge; g, back iron ; A, hairs ; i, dam-block ; Ar, speer- ing or oblique block, between the two stampers ; /, ditto ; n, ditto ; tw, spring wedge. When in the course of a few minutes the bruised seeds are sufficiently heated in the pans, the double door FF is with- drawn, and they are received in the bags, below the aperture G. These bags are made of strong twilled woollen cloth, woven on purpose. They are then wrapped in a hair-cloth, lined with leather. The first pressure requires only a dozen blows of the stamper, after which the pouches are left alone for a few minutes till the oil has had time to flow out ; in which interval the workmen prepare fresh bags. The former are then unlocked, by making the stamper fall upon the loosening wedge or key, m. The weight of the stampers is usually from 500 to 600 pounds ; and the height from which they fall upon the wedges is from 16 to 21 inches. Such a mill as that now described, can produce a presstire of from 50 to 75 tons upon each cake of the following dimensions : 8 inches in the broader base, 7 inches m the narrower, 18 inches in the height ; altogether nearly 140 square inches in surface, and about | of an inch thick. OILS, ADULTERATION OF. M. Heidenreich has found in the application of a few drops of sulphuric acid to a film of oil, upon a glass plate, a means of ascer- taining Its purity. The glass plate should be laid upon a sheet of white paper, and a drop of the acid let fall on the middle of ten drops of the oil to be tried. With the oil of rape-seed and turnip-seed, a greenish blue ring is gradually formed at a certain distance from the acid, and some yellowish brown bands proceed from the centre. With oil of black mustard, in double the above quantity, also a bluish green color. With whale and cod-oil, a peculiar centrifugal motion, then a red color, increasing gradually in intensity ; and after sometime, it becomes violet on the edges. With oil of cameline, a red color, passing into bright yellow. Olive-oil, pale yellow, into yellowish green. Oil of poppies and sweet almonds, canary yellow, passing into an opaque yellow. Of linseed, a brown magma, becoming black. Of tallow or oleine, a brown color. In testing oils, a sample of the oil imagined to be present should be placed alongside of the actual oil, and both be compared in their reactions with the acid. A good way of approximating to the knowledge of an oil is by heating it, when its peculiar odor becomes more sensible. Specific gravity is also a good criterion. The following table is given by M. Hei- denreich : — o j L_5 Oleine oi Tallow Oil Oil of Turnip Seed Rape Oil - Olive Oil - Purified Whale Oil Oil of Poppies Oil of Camelina - Linseed Oil- Castor Oil - Sp. Gr. Gay-Lussac's Alcoholm. . 0-9003 66 - 0-9128 60-75 - 0-9136 60-20 • 0-9176 58-40 - 0-9231 55-80 - 0-9243 55-25 - 0-9252 54-75 0-9347 50 0-9611 33-75 M. Laurot, a Parisian chemist, finds that colza oil (analogous to rapeseed oil) maf be tested for sophistication with cheaper vegetable oils by the increase of density 302 OILS, TESTS OF. OILS, TESTS OF. 303 5 N I which it therefrom acquires, and which becomes very evident when the several oils are heated to the same pitch. The instrument, which he calls an oleometer, is merely a hydrometer, with a very slender stem. He plunges it into a tin cylinder, filled with the oil, and sets this cylinder in another containing boiling water. His oleometer is so graduated as to sink to zero in pure colza oil so heated ; and he finds that it stops at 210* in linseed oil, at 124^ in poppy-seed oil, at 83'^ in fish oil, and at 136'^ in hemp- seed oil — all of the same temperature. By the increase of density, therefore, or the ascent of the stem of the hydrometer in any kind of colza oil, he can infer its degree of adulteration. The presence of a fish oil in a vegetable oil is readily ascertained by agitation with a little chlorine gas, which blackens the fish oil, but has little or no effect upon the vegetable oil. I find that lard oil, and also hogs' lard, are not at all darkened by chlorine. A specific gravity, bottle or globe, having a capillary tube-stopper, would make an excellent oleometer, on the above principle. The vessel should be filled with the oil, and exposed to the heat of boiling water, or steam at 212^, till it acquires that tem- perature, and then weighed. The vessel with the pure colza oil will weigh several grains less than with the other oils similarly treated. Such an instrument would serve to detect the smallest adulterations of sperm oil. Its specific gravity at 60^ when pure is only 0-875 ; that of southern whale oil is 0-922, or 0-925 ; and hence their mixture will give a specific gravity intermediate, according to the proportion in the mixture. Thus I have been enabled to detect sperm oil in pretended lard oil, in my examination of oils for the customs. OILS ESSENTIAL, Tests of Furitj/. \. 01. Amygdalarum amar. {Bitter Almonds). This oil possesses, besides its specific gravity and peculiar smell, so many striking chemi- cal characteristics, that any adulteration of it must be easily detected. To these cha- racteristics belong its great ^eox solubility in sulphuric acid, with a reddish brown colora- tion and wittumt any visible decomposition ; the very slow action which nitric acid has upon it, without either of the two substances undergoing any change in its physical pro- perties ; the only partial slow solution of iodine without further reaction ; the indiflference to chromate of potash ; the elimination of crystals from its solution in an alcoholic solvr tion of caustic potash ; the peculiar inspissation by caustic ammonia and muriatic acid, and the elimination of crystals from the alcoholic solution of these new compounds, and lastly, the decidedly acid reaction ; in short, almost by every reagent some peculiarity of this oil is displayed, by which its purity can be perfectly and easily established. 2. 01. Caryophyllorum {Cloves). The properties which this oil possesses afford great opportunity of discovering its purity. Firstly, its relation to the alcoholic solution of caustk potash, with which it congeals entirely mto a crystalline mass, totally losing at the same time the clove odmir. Any foreign substance present would be excluded from this compound, or would interrupt and weaken it Similar to this, and equally marked, is the butyraeeous coagulum, which is obtained by shaking the oil with a solution of caus- tic ammonia, and which, after fusion, crystallizes. The spontaneous ready decomposition by nitric acid, and simultaneous formation of a reddish brown solid mass, as also the dark blue coloration of the oil by a small quantity of sulphuric acid, whilst a greater portion of the latter changes the oil into a blood red solid mass, are equally striking tests. To these we may add the perfect decomposition of the oil into brown flakes by ehrmnate of potash, accompanied by the loss of the yellow colour of the solution of this salt ; the solubility of iodine, which forms with it a liquid extract, with but a small increase of temperature, and also the perfect and easy solubility of sautaline in it. 3. 01. Cinnamomi {Cinnamon). With this oil the question is not merely to detect an adulteration with other oils, but also to distinguish the two sorts of this oil from one another, viz., the Ceylon oil {oleum, cinnamomi verum) and the Chinese oil {oleum cassics) which differ very much in price. In both cases it is difllicult to obtain accurate tests of the properties of these oils, as they are almost exclusively obtained by way of commerce, and vary considerably in their qualities, on account of their age and careless method of preparation. The chief distinction between the two oils is the odour : the Ceylon oil is, moreover, more liquid, and of a less specific weight than the Chinese, and may be exposed to a greater degree of cold than the latter without becoming turbid. The most distinguishing characteristic of the cinnamon oils is, perhaps, their relation to the alcoholic solution of caustic potash : both dissolve in it readily and clear, with a red- dish yellowish brown colour; after some time, however, the solution becomes very turbid, and a rather heavy undissolved oil precipitates, whilst the solution gradually becomes clear again. Another peculiar character is, where the oil is being decomposed by nitric acid a smell of bitter almond oil is perceptible. Both oils are at the same time converted into a brown balsam ; in the Ceylon oil a brisk decomposition occurs sooner, and at a slighter heat. Iodine dissolves rapidly in the Ceylon oil with a considerable increase of heat, and a slight expulsive movement, a tough extract-like substance remaining behind. With the Chinese oil the reaction is slow, the development of heat but very slight, quiet, and the residue a soft or liquid substance. Chromate of potash decomposes partially the Ceylon oil into brown flakes, which are suspended in the solution. This is deprived of its yellow colour, whilst the undecom- posed portion of the oil assumes a yellowish light red colour, and becomes thick. The solution treated with Chinese oil does not entirely lose its yellhia, which adhere to the sides of the vessel from the light, pointed crystals of narco- tine, which for the most part float in the fluid, is to be effected by decantation, according to Guillermond, but this plan does not leave the morphia free from narcotine. In order effectually to separate the narcotine, the adhering meconate of ammonia must be re- moved by washing in water, and then shaking the crystals in pure ether, or better still in chloroform, by which the narcotine is readily dissolved, while the morphia remains entirely insoluble. After this treatment the morphia is left behind in rather large gritty crystals, slightly discoloured. This process may be varied by employing boiling alco- hol and powdered opium, and adding the solution, still hot» to the solution of ammonia. According to Guillermond, 16 grammes of opium should yield at least 125 grammes or 8-33 per cent Reich estimates 10 per cent, and others 12 per cent The author gives the percentage of morphia which is obtained by the various processes of differ- ent experimenters, and states that the largest proportion (13-60 per cent) is procured by the modification of Guillermond's method, now described, which he also considers ihe simplest and most certain for ascertaining the proportion of morphia. The following process is recommended by Dr. Rieget for the detection of small gaantities of opium- To the suspected substance, some potash is to be added, and then it is shaken with ether. A strip of white blotting paper is to be moistened with the solution, several times repeated. When dry, the paper is then to be moistened with muriatic acid, and exposed to the steam of hot water ; if opium be present^ the paper will be more or less coloured red- Imported, in 1850, 126,102 lbs., in 1851, 106,113 lbs. ; retained for consumption, 1850, 42,324 lbs., 1857, 50,368 lbs. ; exported, 1850, 87,451 lbs., 1851, 65,640 lbs. : duty tweived, 1860, 2,222/L, 1861, 2,645/. ^ OPOBALSAM is the balsam of Pern in a dry state. OPOPONAX is a gum-resin resembling gum ammoniac. It is occasionally used m ■ledicine. ORANGE DYE is given by a mixture of red and yellow dyes in various proportions. Annotto alone dyes orange ; but it is a fugitive color. ORCINE is the name of the coloring principle of the lichen dealbatua. The lichen dried and pulverized is to be exhausted by boiling alcohol. The solution filtered hot, lets fall in the cooling crystalline flocks, which do not belon? to the coloring matter. The supernatant alcohol is to be distilled off, the residuum is to be evaporated to the consistence of an extract, and triturated with water till this liquid will dissolve no more. The aqueous solution reduced to the consistence of sirup, and left to Itself in a cool place, lets fall, at the end of a few days, long brown brittle needles, which are to be freed by pressure from the mother water, and dried. That water being treated with animal charcoal, filtered and evaporated, will yield a second crop of crystals. These are orcine. Its taste is sweet and nauseous ; it melts readily in a retort into a transparent liquid, and distils without undergoing any changes. It is soluble in water and alcohol. Nitric acid colors it blood-red ; which color afterwards disappears. Subacetate of lead precipitates it completely. Its conversion into the archil red IS effected by the action of an alkali, in contact with the air. When dissolved, for example, in ammonia, and exposed to the atmosphere, it Ukes a dirty brown red hue ; but when the orcine is exposed to air charged with vapors of ammonia, it assumes by degrees a fine violet color. To obtain this result, the orcine in powder should be placed in a capsule, alongside of a saucer containing water of ammonia ; and both should be covered by a large bell glass ; whenever the orcine has acquired a dark bvown cast, it must be withdrawn from under the bell, and the excess of ammonia be tilowed to volatilize. As soon as the smell of ammonia is gone^ the orcine is to be dia* ORNAMENTAL BRASS CASTINGa 309 solved in water ; and then a few drops of ammonia being poured into Ue brownish liquid, It assumes a magnificent reddish-violet color. Acetic acid precipitates the red lake of lichen. ORES (Mines, Fr. ; Erze, Germ.), are the mineral bodies which contain so much metal as to be worth the smelting, or being reduced by fire to the metaUic state. The substances naturally combined with meUls, which mask their metallic characters, are chiefly oxygen, chlorine, sulphur, phosphorus, selenium, arsenic, water, and several acids, of which the carbonic is the most common. Some metals, as gold, silver, platinum, often occur in the metallic state, either alone, or combined with other metals, constituting what are called native alloys. I have described in the article Mine, the general structure of the great metallic repositories within the earth, as well as the most approved jnethods of hringine them to the surface ; and in the article Metallurgy, the various mechanical and chemical operations requisite to reduce the ores into pure metals. Under each particular metaL moreover, in its alphabetical place, wiU be found a systematic account of its most imoor! tant ores. *^ Relatively to the theory of the smelting of ores, the following observations mav be made. It is probable that the coaly matter employed in that process is not the immediate agent of their reduction ; but the charcoal seems first of all to be transformed by the atmospherical oxygen into the oxyde of carbon ; which gaseous product then surrounds and penetrates the interior substance of the oxydes, with the effect of decom- posing them, and carrying off their oxygen. That this is the true mode of action it evident from the well-known facts, that bars of iron, stratified with pounded charccJaL in the steel cementation-chest, most readily absorb the carbonaceous principle to thSr innermost centre, while theu- surfaces get blistered by the expansion of carbureted gases formed within ; and that an intermixture of ores and charcoal is not always necessary to reduction, but merely an interstratification of the two, without intimate contact of the particles. In this case, the carbonic acid which is generated at the lower surfaces of contact of the strata, rising up through the fii^t bed of ignited charcoal be- comes converted into carbonic oxyde; and this gaseous matter, passing up through the next layer of ore, seizes its oxygen, reduces it to metal, and is itself thereby transformed once more into carbonic acid; and so on in continual alternation. It may be hud down, however, as a general rule, that the reduction is the more rapid and complete the more Jl^timate the mixture of the charcoal and the metallic oxyde has been, because the formation of both the carbonic acid and carbonic oxyde becomes thereby i^re easy and direct. Indeed, the cementation of iron bars into steel will not succeed, unless the charcoal be so porous as to contain, interspersed, enough of air to favor the commence- ment of its conversion into the gaseous oxyde; thus acting like a ferment in brewing. Hence also finely pulverized charcoal does not answer weU ; unless a quantity of grouui iron cinder or oxyde of manganese be blended with it, to afford enough of oxygen to be- gin the generation of carbonic oxyde gas; whereby the successive transformations into acid, and oxyde, are put in train. ORMOLU. The ormolu of the brass founder, popularly known as an imitation of red gold, 18 extensively used by the French workmen in metals. It is generally found m combination with grate and stove work. It is composed of a greater proportion of copper and less zinc than ordinary brass, is cleaned readily by means of acid, and is burnished with facility. To give this material the rich appearance, it is not unfre- quently brightened up after " dipping " (that is cleaning in acid) by means of a scratch brush (a brush made of fine brass wire^ the action of which helps to produce a very niTv Al?J.t 'l^ aV"^^^^^ ^* '* protected from tarnish by the applicafion of lacque?. OUxNAMEIsTAL BRASS CASTINGS. Brass castings are produced in san^ by means of patterns. The making of these patterns or models is a work involving nJ t^rlmtr^K f ^^ '^" *?^ knowledge ; the simpler kinds are made by the ordinary tZ h^n^r^f f1 ^°j;?««» ^here figures, foliage, or animals are introduced, the eye anJ ^ wax r o^tTn / J"- T^ necessary. The object is first designed, then modelled patl^n or'mTdel^r 1"^^^^^^^^ ' '' " ^'^"^ "^^ "^ ""^'^ ^^^ ^^^^^ ' ^^ ^-^ ^« anl^fiToTf^r^''^*'' ?^«^°]P'e forms are readily copied; but when the human figure, !ff Tfti'K ^^^^ '? introduced, the difficulty U increased. The castings can onfy be Sfted outfn'^lTn^^^^^^ Tf"^ ^^^' ^^"?^"^g r«^««f «^^«fore the mode! canU removed, and which afterward are bfst exD dn th« m.^n f"^"^ ^^^^^^ *^^ "^'^^ *^^ «^*°^ "P^^ '^ i^ examined, wiU ^ows whin 1 eo?« h«« ^ ""^ -^^'^ '^"*^" ^"^^ «^ compartment marked thereon^ and nroLJa Wr fmni •^^'^ '" .* "^^^^^ ^*^^^"g- ^o put the sand in a condition to duceHhe moulZ^.lZrh P^.^^^^^ ^^^^coal is dusted upon it, the cores being intro- duced, the moulds closed having been previously dried, and runners made for the m- 310 OXALIC ACID. OXALIC ACID. 311 troduction of the metal (which is usually melted in earthen or clay crucibles, and in an air furnace, the fuel used being coke), follow and complete the operation. ORPIMENT (Ens. and Fr., Yellow sulphuret of arsenic ; Operment, Rauschgelb, Germ.), occurs in indistinct crystalline particles, and sometimes in oblique rhomboidal prisms ; bat for the most part, in kidney and other imitative forms ; it has a scaly and granular aspect ; texture foliated, or radiated ; fracture small granular, passing into conchoidal ; splintery, opaque, shining, with a weak diamond lustre ; lemon, orange, or honey yellow ; sometimes green ; specific gravity, 3-44 to 3-6. It is found in floetz rocks, in marl, clay, sand-stone, along with realgar, lead-glance, pyrites, and blende, in many parts of the world. It volatilizes at the blowpipe. It is used as a pigment. The finest specimens come from Persia, in brilliant yellow masses, of a lamellar tex- ture, called golden orpiment. Artificial orpiment is manufactured chiefly in Saxony, by subliming in cast iron cucur- bits, surmounted by conical cast-iron capitals, a mixture in due proportions of sulphur and arsenious acid (white arsenic). As thus obtained, it is in yellow compact opaque masses, of a glassy aspect ; afibrding a powder of a pale yellow color. Genuine orpiment is often adulterated with an ill-made compound; which is sold in this country by the preposterous name of king's yellow. This fictitious substance is fre- quently nothing else than white arsenic combined with a little sulphur ; and is quite soluble in water. Il is therefore a deadly poison, and has been administered with criminal intentions and fatal effects. I had occasion, some years ago, to examine such a specimen of king's yellow, with which a woman had killed her child. A proper insoluble sulphuret of arsenic, like the native or the Saxon, may be prepared by trans- mitting sulphureted hydrogen gas through any arsenical solution. It consists of 38-09 tulphur, and 60-92 of metallic arsenic, and is not remarkably poisonous. The finest kinds of native orpiment are reserved for artists; the inferior are used for the indigo Tat They are all soluble in alkaline lyes, and in water of ammonia. OR YCTNOGNOSY, is the name given by Werner to the knowledge of minerals ; and is therefore synonymous with the English term Mineralogy. OSTEOCOLLA, is the ^lue obtained from bones, by removing the earthy phospliates with muriatic acid, and dissolving the cartilaginous residuum in water at a temperature considerably above the boiling point, by means of a digester. It is a very inditferent article. OSMIUM, is a metal discovered by Mr. Tennant in 1803, among the grains of native platinum. It occurs also associated with the ore of iridium. As it has not been ap- plied to any use in the arts, I shall reserve any chemical observations that the subject may require for the article Platinum. OTTO OF ROSES.— Meatis of determining the nurity of the Otto of Roses.— Sul- phuric acid test. — One or two drops of the oil to be tested is put into a watch-glass ; the same number of drops of very concentrated sulphuric acid are added, and the two fluids mixed with a glass rod. All the oils are rendered more or less brown by this proceeding ; but the otto of roses retains the purity of its odour. The oil of geranium acquires a strong and disagreeable odour, which is perfectly characteristic. OXALATES are saline compounds of the bases with OXALIC ACID (jScide oxaliquey Fr. ; Sauerkleesaiire, Germ.), which is the objcci of a considerable chemical manufacture. It is usually prepared upon the small scale by digesting four parts of nitric acid of specific gravity 1-4, upon one part of sugar, in a glass retort ; but on the large scale, in a series of salt-glazed stoneware pipkins, two thirds fiUed, and set in a water bath. The addition of a little sulphuric icid has been found to increase the product. 15 pounds of sugar yield fully 17 pounds c. the cr)-sta]Iine acid. This acid exists in the juice of wood sorrel, the oxalis acetosella, in the slate of a bi- oxalate ; from which the salt is extracted as an object of commerce in Sw^itzerland, and sold under the name of salt of sorrel, or sometimes, most incorrectly, under that of salt of lemons. Some prefer to make oxalic acid by acting upon 4 parts of sugar, with 24 parts of nitric acid of specific gravity 1-220, heating the solution in a retort till the acid begins to decompose, and keeping it at this temperature as long as nitrous gas is disengaged. The sugar loses a portion of its carbon, which combining with the oxygen of the nitric acid, becomes carbonic acid, and escapes along with the deutoxyde of nitrogen. The re- maining carbon and hydrogen of the sugar being oxydized at the expense of the nitric acid, generate a mixture of two acids, the oxalic and the malic. Whenever gas ceases to issue, the retort must be removed from the source of heat, and set aside to cool; the oxalic acid crystallizes, but the malic remains dissolved. After draining these crystals upon a filter funnel, if the brownish liquid be further evaporated, it will furnish another crop of them. Vie residuary mother water is generally regarded as malic acid, but it also contains both oxalic and nitric acids ; and if heated with 6 parts of the latter acid, it will yield a good deal more oxalic acid at the expense of the malic. The brown crystals BOW formed being, however, penetrated with nitric, as well as malic acid, must be allowed to dry and eflloresce in warm dry air, whereby the nitric acid will be got rid of without injury to the oxalic. A second crystallization and efflorescence will entirely dissipate the remainder of the nitric acid, so as to afford pure oxalic acid at the third crystallization. Sugar affords, with nitric acid, a purer oxalic acid, but in smaller quantity, than saw-dust, glue, silk, hairs, and several other animal and vegetable substances. Oxalic acid occurs in aggregated prisms when it crystallizes rapidly, but in tables of greater or less thickness when slowly formed. They lose their water of crystallization in the open air, fall into powder, and weigh 0-28 less than before ; but still retain 0-14 parts of water, which the acid does not part with except in favor of another oxyde, as when it is combined with oxyde of lead. The effloresced acid contains 20 per cent, of water, according to Berzelius. By my analysis, the crystals consist of three prime equivalents, of water = 27, combined with one of dry oxalic acid = 36 ; or in 100 parts, of 42-86 of water with 57*14 of acid. The acid itself consists of 2 atoms of carbon = 12, -f- 3 of oxygen = 24 ; of which the sum is, as above stated, 36. This acid has a sharp sour taste, and sets the teeth on edge ; half a pint of water, containing only 1 gr. of acid, very sensibly reddens litmus paper. Nine parts of water dissolve one part of the crystals at 60^ F. and form a solution, of spec. grav. 1*045, which when swallowed acts as) a deadly poison. Alcohol also dissolves this acid. It differs from all the other acid pro- ducts of the vegetable kingdom, in containing no hydrogen, as I demonstrated (in my paper upon the ultimate analysis of organic bodies, published in the Phil. Trans, for 1822), by its giving out no muriatic acid gas, when heated in a glass tube with calomel or cor- rosive sublimate. Oxalic acid is employed chiefly for certain styles of discharge in calico-printing (which tee), and for whitening the leather of boot-tops. Oxalate of ammonia is an excellent re- agent for detecting lime and its salts in any solution. The acid itself, or the bi-oxalate of potash, is often used for removing ink or iron-mould stains from linen. A convenient plan of testing the value of peroxyde of manganese for bleachers, &-c., originally proposed by Berthier, has been since simplified by Dr. Thomson, as follows. In a poised Florence flask weigh 600 grains of water, and 75 grains of crystallized oxalic acid ; add 50 grains of the manganese, and as quickly as possible afterwards from 150 to 200 grains of concentrated sulphuric acid. Cover the mouth of the flask with paper, and leave it at rest for 24 hours. The loss of weight it has now suffered corresponds exactly to the weight of peroxide of manganese present ; because the quantity of car- bonic acid producible by the reaction of the oxalic acid with the peroxide is precisely equal to the weight of the peroxide, as the doctrine of chemical equivalents shows. By exposing 100 parts by weight of dry sugar to the action of 825 parts of hot nitric acid of 1-38 specific gravity, evaporating the solution down to one-sixth of its bulk, and setting it aside to crystallize, from 58 to 60 parts of beautiful crystals of oxalic acid may be obtained, according to Schlesinger. Oxalic acid may be produced by the action of nitric acid upon most vegetable sub- stances, and especially from those which contain no nitrogen, such as well washed saw- dust, starch, gum, and sugar. The latter is the article generally employed, and possesses many advantages over every other material. Treacle, which is a modification of sugar, also comes within the same ranges. A very contemptible spirit of exaggeration prtw vails in respect to the amount of produce attainable by oxalic acid makers from a given weight of sugar. The generality of the statements is absurdly false. One cwt. of good treacle will yield about 116 lbs. of marketable oxalic acid, and the same weight of good brown sugar may be calculated to produce about 140 lbs. of acid. As a general rule, 5 cwts. of saltpetre, or an equivalent of nitrate of soda, with 2^^ cwts. of sulphuric acid, will generate suflieient nitric acid to decompose 1 cwt. of good sugar, and yield, as above, 140 lbs. of fair marketable oxalic acid, free from superfluous moisture. Any hope of improvement seems directed rather to an economy of nitric acid, than to an increased production of oxalic acid from a given weight of sugar. Tlie process is carried on either in large wooden vessels, or in small earthenware jars disposed in a water-bath, each jar having a capacity of about a gallon or less ; the specific gravity of the nitric acid need not be so high when operating on the large scale, in a wooden trough, as when employing the earthenware jars. From 1-200 to 1-270 is the range ; and the tem- perature m neither case should much exceed or fall short of 125° Fahr. The favourable symptoms are a regular and tolerably active evolution of gas without the appearance of red fumes, and a peculiar odour which only faintly recals the smell of nitric oxide. Tlie gases evolved consist, nevertheless, of nitric oxide and carbonic acid, but the influ- ence of this latter gas has a remarkable effect in arresting the aflftnity of the nitric oxide for oxygen. So long as the carbonic acid is present, the mixture may be mingled with its own bulk of oxygen gas, without any diminution of volume, for several minutes, or the production of red fume ; but the moment a little ammonia vapour is applied, so at n 312 OXALIC ACID. to condense the carbonic acid, the whole becomes of a deep orange hue. Herein Iie« a difficulty connected with the re-conversion of the nitric oxide into nitric acid by th« action of atmospheric oxygen ; and for the same reason, the employment of these gases in the manufacture of sulphuric acid has not answered the expectations of those who have tried the experiment practically. Carbonic acid would appear to possess, not sim- ply a neutral agency in obstructing oxidation, but a negative power of preventing it How far blowing atmospheric air through the acidulous saccharine solution, during the process of oxalic acid making, might tend to economize the consumption of nitric acid, we cannot pretend to say ; but as the nitric acid really forms the chief item of expense, it is by such expedients that a saving may possibly be effected. When sti-ong nitric acid is boiled upon sugar, in the way recommended in mamy chemical works, for the produc- tion of oxalic acid, a great loss of all the materials ensues; and most of the oxalic acid being peroxidized passes off as carbonic acid, leaving scarcely as much acid behind as is equivalent to half the weight of the siigar employed. This accounts for the dis- crepancies which have been published in this branch of manufacture. Almost tlie only commercial article made from oxalic acid is the binoxalate of potash or salt of sorrel. This substance results from the decomposition of carbonate of potash by an excess of oxalic acid. The carbonate of potash is first dissolved in hot water, and the oxalic acid added until the effervescence ceases ; after which a similar quantity of oxalic acid to that previously employed is thrown in, and the solution is boiled for a few minutes; and then it is set aside to crystallize. The crystals, after being drained and dried, are fit for the market j Manufacture of Oxalic Acid Oxalic acid is formed by the action of nitric acid om 1'200 to 1-270 are about the limits of the range allowed for the gravity of the acid. As regards the temperatures of the baths, this should be maintained at or about 126° Fahr. Whilst the operation is in progress, the active evolution of gas, without the appearance of red fumes, and the emission of a peculiar smell, slightly indicative of the presence of nitric oxide, are amongst the signs that every thing is in good working condition. The judicious addition of sulphuric acid is found to contri- bute to an increase of the quantity of oxalic acid produced. The product of acid from a given quantity of sugar has been much undei'stated by chemical writers: this has most probably arisen from the circumstance of boiling the sugar with strong nitric acid, by which means a large quantity of oxalic acid becomes converted, as soon as formed, into carbonic acid, and the result is, that the actual product of oxalic acid ob- tained represents only about one-half of the sugar employed, and therefore not above one-half the quantity which should have been obtained. Thus we find it stated, that from 60 to 60 lbs. of oxalic acid are obtainable from 100 lbs. of good sugar, whereas the quantity actually obtained in practice is from 1 26 to 130 lbs. lYeacle of course gives a smaller product; 100 lbs. of fair quality yielding from 105 to 110 lbs. of oxalic acid. The mother liquor having been poured off, the crystals of acid obtained are thrown on drainers and washed, then carefully dried in a suitable stove. The mother liquors, when treated with a fresh supply of nitric acid and treacle, are ready for a further operation. About 4% cwts. of nitrate of soda, and 2^ cwts. of sulphuric acid, are used to furnish the nitric acid required to convert 1 cwt of good sugar into oxalic acid. Mr. Jullion has patented a process for the conversion of formic acid into oxalic acid. For this purpose, formic acid is saturated with a solution of caustic potash, and then half the quantity of caustic potash required for saturation is added to the above mixture ; the whole is then evaporated to dryness, and heated to 560° Fahr. By this process, the formic acid is decomposed, and oxalate of potash formed. Caustic soda may also be employed instead of caustic potash. The oxalate of potash or of soda thus obtained is then treated with sulphuret of barium, hydrate of baryta, or any soluble salt of baryta, whereby an oxalate of baryta is precipitated, from whence pure oxalic acid maj' be obtained by means of sulphuric acid. Another mode of obtaining oxalic acid is by the process patented by Dr. Wilton Turner, who directs the uric acid obtained from guano to be treated with peroxide of lead or manganese suspended in water, at a boiling temperature, by which means it will be decomposed into oxalic acid, allantoin, urea. The oxalic acid forms an insoluble compound with the lead or manganese. The lead process is as follows : A known w^ht of uric acid is placed in an open cylindrical iron vessel, capable of holding two pounds of water for every pound of the acid, and adapted to boil by steam. A clear saturated solution of lime water is then added, and as soon as it is heated, and in brisk ebullition, the peroxide of lead is added in successive portions, as long as it is observed to be whitened by the boiling liquid. The whitish powder thus obtained is oxalate of lead. About 240 lbs. of peroxide of lead are required for each 1 68 lbs. of uric acid employed. Tlie supernatant liquor is next drawn ofl^ and the oxalate of lead washed with clear water; this is then boiled with dilute muriatic acid [equal parts of acid and water], by means of which oxalic acid is obtained in solution, which is evaporated and crystallized, whilst muriate of lead remains as the precipitate. The allantoin is also decomposed into oxalic acid and ammonia by boiling it with caustic alkali. The former unites with the alkali used, while the ammonia passes over, and may be collected as liquid ammonia; the oxalic acid thus generated may be obtainea as oxalate of potasli, if potash be the alkali employed, or as oxalic acid if baryta be used, by decomposing the latter oxalate by means of sulphuric acid. In this case, the oxalate of baryta may be treated in the way previously described for oxalate of lead. This process is delusive. As regards these various methods for obtaining oxalic acid, their employment will Vol. IL 2 S 314 OXALIC ACID. of course always be a question of £. s. d., the economy of many operations of manu facturiug chemistry being often dependent upon their adaptation to the requirement* or purposes of particular manufactures, in connection with other branches of manufac- ture carried on by them. The low price at which treacle and sugar are now obtainable is much in favour of their use in this manufacture. The chief point, however, to which attention must be directed, in order to lessen the cost of production of this article, is in economizing the nitric acid used. In speaking of the action of nitric acid upon sugar, it was observed that carbonic acid was produced, and that it passes oflf with the deutoxide of nitrogen also set at liberty. The presence of carbonic acid, in this case, proves a great obstacle in the reconversion of nitric oxide into nitric acid, preventing the union of the oxygen of the air with the nitric oxide. Various processes have been from time to time suggested to effect this economy in the manufacture of oxalic acid : amongst these, the following may more particularly be noticed : — In 1846, Mr. Jullion patented a method of converting the ojrides of nitrogen given off in the manufacture of oxalic acid, into nitrous and nitric acids. For this purpose, he uses a " generating vessel," which is a vessel something like a Woulfes' bottle, only having a moveable top fitting air-tight, and capable of holding about 100 gallons. The materials to form the oxalic acid are introduced, and the vessel heated by a water-bath (by steam or other convenient means^ which surrounds the vessel ; a quantity of nitric acid is then added, and air or oxygen is forced in through a pipe inserted in the top. The oxygen, coming in contact with the evolved oxides of nitrogen, immediately con- verts a portion into nitrous and hyponitrous acids, which are partly again absorbed by the fluid in the vessel ; another portion passes off by a pipe inserted in the upper part of the vessel, which pipe passes through a furnace. This part in the furnace is a little enlarged, and is heated from 600° to 900° Fahr. ; this part of the pipe or tube contains spongy platinum, or other similar substances ; the gases, in coming in contact with the heated platinum, combine to form nitric acid, which is afterwards condensed in vessels arranged as usual in the manufacture of this acid. Instead of platinum a close vessel containing water may be used, which decomposes hyponitrous and nitrous acids, giving rise to nitric acid. This principle is applied in the following ways :— -the oxides of nitrogen, as evolved from the liquor in the decomposing vessel, coming in contact with oxygen, are converted into hyponitrous and nitrous acids, which, upon being mingled ■with steam, are decomposed into nitric acid and binoxide of nitrogen ; or the intro- duction of steam may be obviated, by using heated air or oxygen in the decomposing vessels, by which means moisture will be furnished from the liquor ; the amount of evaporation thus caused will also prevent an inconvenient increase of the mother-liquor. The compounds thus formed, when passed through suitable condensers, will, if the supply of atmospheric air or oxygen has been in excess, be all or nearly all condensed into nitric acid. , . , The following is a description of Crane and Jullion s continuous method of manO' facturing oxalic acid and nitric acid at one process : — the oxalic acid mother-liquor of a previous process is placed in a close or covered vessel, termed a " generator," formed of slate ; nitric acid and syrup in the usual proportions employed for such quantity of mother-iiquor are also placed separately in feeding vessels, over the " generator;" heat is then applied to the mother-liquor, and the temperature raised as quickly as possible to 180° or 200° Fahr, Streams of nitric acid and symp are then caused to flow into the generator by means of suitable stop-cocks and funnel-pipes, in such a quantity that the delivery of the whole shall occupy about 18 houi-s, at the expiration of which time the process will be completed. The gases arising from the decomposition of the materials so supplied pass off through an eduction pipe in the top of the generator, into a receiver, into which a stream of chlorine is introduced (from a chlorine generator) sufficient to convert the whole of the oxides of nitrogen into nitric acid. A portion of water in the receiver is decom- posed, its oxygen combining with the oxide of nitrogen to form nitric acid, whilst ita hydrogen combines with the chlorine to form hydrochloric acid. These mixed vapours pass over into suitable condensing vessels placed to receive thenu The whole of the nitric acid and syrup having been run in, and the liberation of the gases or oxides of nitrogen having ceased, the oxalic acid liquor is drawn off from the generator and crystallized. Messrs. M'Dougall and Rawson have patented a method of recovering the vapours which pass off in the manufacture of oxalic acid. To effect this, they direct the employment of a series of vessels containing water, into the first of which the nitrous gas or fames are passed, through a tube dipping below the surface of the vessel ; air is also admitted, which mixes with the gas bubbling up through the water. Attached to the last vessel of the series is a pneumatic apparatus, by means of which the mixture of ., OXALIC ACID. 815 nitrous gas and air are drawn through this series of v^e^ eac^ ^-^^J^cf i' wul'tJS; Ig "tf The liquid, and another tube or pipe ^^-^^^^^ l^^L and water, becomes d^tTf in^^:!^^^^^^^ --^- - -'' '' "'^ ^rnT^ O.being P-d in^ wat. of J.^ t^^^^^^^^ 2 N 05 + N O, result, the 2 ^ ^^l^^^J^^t^^^i^^^^ liquid, and unites with the N 0» which is an mcondensable gas, ^"f^^^^^^^^ ^akes two atoms of oxygen the air in the vessel above the Hl"^ ^^^J™J"th^^^^^^^ liquid becomes nitric acid from the air, and becomes ^ O. whic^^P^^^^^^^^^ ,,,, Citrous fumes or gas are and nitrous gas, as before, and tbus neany tuc reconverted into nitric ^cid. recovering the nitric acid, he fills his regenerating In Ecarnot's patented process^^^^^^^^ 1 i^^ the oxygen by vessels with a porous substance, ^^\" ", ^ y^^ from a boiler. blowing machine, a flow oV'XJri^cid-Arno^^^^ account of the decompos.- Rationale of the Process for f^f'*^^^ f^^^.f ' "id has vet been published, that 1 am tion which ensues in the °^^'?^^^1"^^,;\S^^^^^ kw att/ntion to this subject aware oC the following experiments may tend pernap^ ^^^^^ .^ ^ water-bath, The apparatus employed co°«^«;^ed of a ^j/J^^i^jehk t«be passed into a two- and luted to a tubulated receiver from ^^^ «P^^\"^j^\P^ ^^^^le was connected by a tube necked bottle containing a ^ol^^^^^^^^^^^Xfuing a slti^ of nitrate of lime, from ;i:!:hTn^^rtU'e^ ;zt^^^^^^' -^ ^--^^ ^^^ --'- -' ^^ ^TeXta^rof ^^r\:-r^i^ r^oirntfta?^"id Fahr. for forty-eight hours in each experiment ^^^^ J^^^^ ^j^^^d to effloresce in » r^Z^ rto^Smrr:^:^ J^t^r^^ were then dissolved, re- and nitrate of lime after each eYerirnen^:alb^^^^^^^^^ ^ ,, four-and-twenty hours, after Y^^?^*?. '\^*^T!1 nothing m weight by prolonged ex- employed was tlie best refined white and ^^^^^^^^^^ J^ of 'specific gravity Dosure to a temperature of 212 . The ^""^. ^^''^^ "I^.^.!-^ 'f i^ weight of dry acid, ? 245 at 60-; it contained as nearly as P«««;^.^^\nJ^^^Xcr^^^^ The as was proved by the amount of pure ^^^^^^/^^^^ P^^X sl^^^^^^ the amount of sugar followin"^ table e'xhibits the results of ei^^^^^^ ^^^^^^.^ ^,,^^ ^^ added to the one following. ______ Number. 1. 2. 8. 4. 6. 6. 7. 8. Employed. Sugar in Ounces. 28 28 28 28 28 28 28 28 Dil. Nitric Acid in Ounces. 184 184 184 184 184 184 184 184 Obtained. Oxalic Acid in Ounces. 32i 30 29i 31i 30i 30i 31 Carbonic Acid in Ounces. "20f 22i 21 21i 22 21 2H 2H tote ogta?ned, as;these may ^^^e^hTr we sha7 h^v^^^^^^^^ of the seven fol- then we omit that experiment ^^^^g^^^f,^' ^.^^^.T J^ted nitric acid have produced lowing, showing that 196 of sugar and 1288 ot miutea m . ^^ ^^i.^^ ^ 2m of oxalic acid, and 150i of carbonic aad, and ^^ j\ ^^ P^^^id, and that by the oxalic acid obtained almost exactly equals that ^J;,f ^f [^^""^arbon of any givea the Sn of nitric acid in the way ^escribed one half of the carD ^^^^J^^^^-^ quantity of sugar is converted jf ^.^^X'^LcTd of va deities and at yarioua Turf ^rioVL^i: 1^^^^^^^^^ ^-'-'"^ -^^^' ^^ 2 S ' 7. 316 OXALIC ACID. fw^ -^ T'T ^f,°»»*^a% diminishes the produce of oxalic acid. Fro» these experiments it would appear that no more than 124 lbs. of oxalic acid can be ob- tamed from 1 cwt of sugar. This I am aware is much below theCantTtvSnerallv ?X"^f ''.i?' P'?^T^ ^" ^^' ^^^^^ .««*^^' «^^ ^»^^«^ i« etIteS to^ vary ftorm^ 140 lbs. for the cwt of sugar; such acid is, however, contaminated w^Ih Xic acS and mother liquor and is moreover decidedly damp, as shown by the mZ^e? in whi'ch the crystals cling to the sides of the bottle in which they are contained some Xw •nee must aho be made for the tendency to exaggeration which prevails'in o™r manu- factcries. These proportions do notgreatly differ from those employed in practice bv oxalic acid makers when allowance is made for the loss of nitric SinddenUl t^ Soyed :- '"*^"^^^^^«- ^he following is the general proportion of matlrial^e^ Sugar - . . , 1 1 o IK Nitrate of potash - - . . I ' Jaa ik!" Sulphuric acid " 280 IK ol'^-en^^'^ ^ ^"'"'^"''^ ^^^ ^^^ ""^ '''^"^ ^""'^ *°^ ^^^ ^^«- ""^ «"^P^^ of potash Experiment has proved to me that the first change produced is to convert the can« Wgar into grape sugar; and as the first portions of gas evolved consist almost entirtTy rLd .r^' ""'^^ little or no carbonic acid, it is dear that some compound is genZ rated in the commencement of this process, which contains the elements of sugar united to an excess of oxygen: the following diagram must therefore be looked on^as merely explanatory of the ultimate change. "icieijr UrS!!!;'^ *Vr'^ ^ *™ '''''^ that !n some hundreds of attempts conducted on a pretty large scale, I have never once exceeded the amount here stated (124 lbs.) when tS acid was properly purified and freed from adhering moisture. The folio wtng dagram^ m my opinion, represents the nature of the ultimate decomposition which^ensu^es^ ^L^;:-^^^^^ ^"^^^^- - unquestionaW produced in^ TeliS Atoms. -4' Materials employed. Common sugar, atom - Nitric acid, Y atoms Carbon - Hydrogen , Oxygen Nitrogen Oxygen - 11 Products. 6 Carbonic acid. Water. 7 Deutoxide of Nitrogen. nYTnTTTrkUTTM? rku n:^*T% * ,. ." 3 Crystallized oxalic acid. UAILHLOKIDE OF LEAD. A white pigment patented by Mr. Hugh Lee Pattin- 8on of Newcastle, which he prepares by precipitating a solution of chloride of lead in not water with pure lime water, in equal measures; the mixture being made with agitation. As the operation of mixing the lime water, and the solution of chloride of lead, requires to be performed in an instantaneous niaaner, the patentee prefers to em- ploy for this purpose two tumbling boxes of about 16 feet cubic capaoitv which are charged with the two liquids, and simultaneously upset into a cistern in which oxi- chlonde of lead is mstantaneously formed, and from which the mixture flows into other cisterns, where the oxichloride subsides. This white pigment consists of one atom of nvmSa *" ^"^ ^^^ ^^^^^ ^^ ^^*^' "^'^^ ""^ without an atom of water nYfii^fi*'"® neutral compounds, containing oxygen in equivalent proportion, f J;i /» ' ^'^ salt J consisting of oxigenated acids and oxides, to distinguish them from the haloseij which are salts consisting of one of the archa^al elemente : such a« chlorine, lodme, bromine, ended, for supplying the colo*" uniformly through the orifice in the mil'stone g. A cord or chain t, by means of which the bucket s is suspended at a proper height for pouring out the requisite quantity of color between the stones, pulls the bucket obliquelj-, and makes its beak rest against the square upright shaft h. By this means the bucket is continually agitated in such a way as to discharge more or less color, according to its degree of inclination. The copper cistern x, receives the color successively as it is ground ; and, when full, it may be carried away by the two handles z, z ; it may be emptied by the stopcock Y, without removing the tub. PAINTS, VITRIFIABLE. See Porcelain, Pottery, and Stained Glass. PALLADIUM, a rare metal, possessed of valuable properties, was discovered in 1803, by Dr. WoUaston, in native platinum. It constitutes about 1 per cent, of the Columbian ore, and from | to 1 per cent, of the Uralian ore of this metal ; occurring: nearly pure in loose grains, of a steel-gray color, passing into silver white, and of a specific gravity of from ll'S to 12*14; also as an alloy with gold in Brazil, and combined with selenium in the Harz near Tilkerode. Into the nitro-muriatic solution of native platinum, if a solu- tion of cyanide of mercury be poured, the pale yellow cyanide of palladium will be thrown down, which being ignited affords the metal. This is the ingenious process of Dr. Wol- laston. The palladium present in the Brazilian gold ore may be readily separated as follows : melt the ore along with two or three parts of silver, granulate the alloy, and di gest it with heat in nitric acid of specific gravity 1-3. The solution containing the silver and palladium, for the gold does not dissolve, being treated with common salt or muriatic k PAPER CUTTING. aai acid TTfll part with all its silver in the form of a chloride. The ^"l^JJ^^^^Y^^"^';'^^^^^^ J^i'rat'ed and neutralized ^th -7--;,-^^^^^ crystals, the ammonia-muriate of palladium, which being wasncu ignited, will afford 40 per cent, of metal. .. * v *\,^ r«rni*.r. nnd if it be The metal obtained by this process is purer than that ^y/f ^^*»J°!^VrP "r foree a fused i^a crucible along with borax, by the heat of a powerful a^r-fura^^^^^^^ "^Th;re are a protoxyde and peroxyde of palladium. The proto-chloride consists of 60 ^.^ It may ll bleached by the action of either chlorine or oxygen g«^ as also b, ^'wm It irp^rte'fin 1860. 447,797 owts, in 1851. 608.650 cwt. ; exported in 185* '''^T,m''vX:'Tlt74:^Uo. of this fabrie is thus ae«.jW in «.e sp^ fication of Mr. Henry Chapman's P-'™' ""'"J^' l„*f;^„i whkh is .X^ endless wire wheel of the machine paper is 'f^^^f'^'J'^^^^^ U the cloth is endless sheet of paper has been led * {^^g^^ Jj^f^^h and moved onwards in tha brought oyer the upper P-J.^/^^^^-^^^Xn oVthe^^^^^^^^^^ r'ler to revolve, direct on the paper is proceeding. The motion oi ^^^Z- "''"';" , , . , |^j ^^jjch it and the adhesive material «?;"- prevent ?roth?ng and add Tpart of glue to the mixture ; after which di ute the whole with ona rnatenTin May 1821, for proposing to conduct the newly formed web of ^aper in treTourdriS machine ov^er heatel cylinders, for the puriK^se of drying i* ^Seditiously, in imitation of the mode so long practised in drj^g calicoes obU.ned. -ilatifen^i^^rti^o'in^J^^^^^^^^^^ Vol. XL ^^ I I 822 PAPER CUTTING. PAPER CUTTING 328 1 i paper, by Mr. Edward Cowper, consisting of a machine, with a ree'i on which the weh of paper of very considerable length has been previously wound, in the act of being made in a Fourdrinier's machine ; this web of paper being of sufficient width to produce two, three, or more sheets, when cut. The several operative parts of the machine are mounted upon standards, or frame- work of any convenient form or dimensions, and consist of travelling endless tapes to conduct the paper over and under a series of guide rollers ; of circular rotatory cutters for the purpose of separating the web of paper into strips equal to the widths of the intended sheets ; and of a saw-edged knife, which is made to slide horizontally for the purpose of separating the strips into such portions or lengths as shall bring them to the dimensions of a sheet of paper. The end of the web of paper from the reel a, fig 1029 is first conducted up an inclined plane b by hand ; it is then taken hold of by endless tapes extended upon rollers, as in Mr. Cowper's Printing Machine, which see. These endless tapes carry the web of paper to the roller c, which is pressed against the roller d by weighted levers, acting upon the plummer blocks that its axle is mounted in. The second roller d may be either of wood or metal, having several grooves formed round its periphery for the purpose of receiving the edges of the circular cutters e, (see Cabd-cuttinq) mounted upon an axle turning upon bearings in the standards or frame. In order to allow the web of paper to proceed smoothly between the two rollers^ e, 4 a narrow rib of leather is placed round the edges of one or both of these rollers^ for the purpose of leaving a free space between {hena, through which the paper may pass without wrinkling. Fi'om the first roller c, the endless tapes conduct the paper over the second d, and then under a pressing roller/, in which progress the edges of the circular knives e, re- volving in the grooves of the second roller d, cut the web of paper longitudinally into strips of such widths as may be required, according to the number of the circular cutters and distances between them. The strips of paper proceed onward from between the knife roller d and pressing rol- ler/, conducted by tapes, until they reach a fourth roller g, when they are allowed to descend, and to pass through the apparatus designed to cut them transversely ; that is, into sheet lengths. The apparatus for cutting the strips into sheets is a sliding knife, placed horizontally upon a frame at A, which frame, with the knife «, is moved to and fro by a jointed rod i, con- nected to a crank on the axle of the pulley k. A flat board or plate / is fixed to the standard frame in an upright position, across the entire width of the machine ; and this board or plate has a groove or opening cut along it opposite to tne edge of the knife. The paper descending from the fourth roller g passes against the face of this board, and as the carnage with the knife advances, two small blocks, mounted upon rods with springs m m, come against the paper, and hold it tight to the board or plate /, while the edge of the knife is pn>vuded forwards into the groove of that board or plate, and its sharp saw-shaped teeth passing through the paper, cut one row of sheets from the descending strips ; which, on the withdrawing of the blocks, falls down, and is collected on the heap below. The power for actuating this machine is applied to the reverse end of the axle, on which the pulley k is fixed, and a band n, n, n, n, passing from this pulley over tension wheels o, drives the wheel q fixed to the axle of the knife roller d ; hence this roller receives the rotatory motion which causes it to conduct forward the web of paper, but the other rollers c and/, are impelled solely by the friction of contact. The rotation of the crank on the axle of fe, through the intervention of the crank-rod i, moves the carriage h, with the knife, to and fro at certain periods, and when the spring blocks m come against the grooved plate i, they slide their guide rods into them, while the knife advances to sever the sheets of paper. But as sheets of different dimensions are occasionally required, the lengths of the slips delivered between each return of the knife are to be regulated by enlarging or diminishing the diameter of the pulley fc, which will of course retard or facilitate the rotation of the three conducting rollers, c, d,/, and cause a greater or less length of the paper to descend between each movement of the knife carriage. The groove of this pulley fe, which is susceptible of enlargement, is constructed of wedge-formed blocks passed through its sides, and meeting each other in opposite direc- tions, so that on drawing out the wedges a short distance, the diameter of the pulley be- comes diminished ; or by pushing the wedges further in, the diameter is increased; and a tension wheel p being suspended in a weighted frame, keeps the band always tight. As it is necessary that the paper should not continue descending while it is held by the blocks m, m to be cut, and yet that it should be led on progressively over the knife roller d, the fourth roller g, which hangs in a lever j, is made to rise at that time, so as to take up the length of paper delivered, and to descend again when the paper is withdrawn. This is eflfectwi by a rod r, connected to the crank on the shaft of the aforesaid roller fc, and also to the under part of the lever j, which lever hanging loosely upon the axle of the knife roller d, as its fulcrum, vibrates with the under roller g, so as to effect the object in the way described. The patentee states that several individual parts of this majhine are not new, and thai some of them are to be found included in the specifications of other persons, such as the circular cutters «, which are employed by Mr. Dickinson (Card-cutting), and the horizon- tal cutter hy by Mr. Hansard ; he therefore claims only the general arrangement of the parts in the form of a machine for the purpose of cutting paper, as the subject of his invention. The machine for cutting paper contrived by John Dickinson, Esq. of Nash Mill was patented in January, 1829. The paper is wound upon a cylindrical roller a, fig. 1030 ,11 1 J J' ^r 1030 y nnr motinted upon an axle, supported in an iron frame or standard. From this roller the paper in its breadth is extended over a conducting drum 6, also mounted upon an axle turnin" in the frame or standard, and after passing under a small guide roller, it process through a pair of drawing or feeding rollers c, which carry it into the suiting machine. ^ . • , j _j Upon a table a, rf, firmly fixed to the floor of the building, there is a series of chisel-edgcd knives c, c, e, placed at such distances apart as the dimensions of the cut sheets of paper are intended to be. These knives are made fast to the table, and against them a series of cu-cular cutters/, /,/, mounted in a swinging frame g, g, are intended to act. The length 334 PAPER CUTTING. PAPER-HANGINGS.^ 325 9* < »r • 1!- -". of paper oeing brought along the table over the edges of the knives, tip to a stop ^, the cutters are then swung forwards, and by passing over the paper against the stationary knives, the length of paper becomes cut into three separate sheets. The frame g,g, which carries the circular cutters/,/,/, hangs upon a very elevated axle, in order that its pendulous swing may move the cutters as nearly in a horizontal line as possible ; and it is made to vibrate to and fro by an eccentric, or crank, fixed upon a horizontal rotatory shaft extending over the drum 6, considerably above it, which may be driven by any convenient machinery. The workmen draw the paper from between the rollers c, and bring it up to the stop h, m the intervals between the passing to and fro of the swing-cutters. The following very ingenious apparatus for cutting the papCT web transversely into any desired lengths, was made the subject of a patent by Mr. E. N. Fourdrinier, in Jane, 1831, and has since been performing its duty well in many establishnents. ^ijr*10^1is an elevation, taken upon one side ot the machine ; and Jig. 1032 is a longi tudinal section, a, a, a, a, are four reels, each cover- ed with one continuous sheet of paper ; which reels are supported upon bear- ings in the frame-work 6, 6, b. c, c, c, is an end- less web of felt -cloth passed over the rollers rf, d, d, d, which is kept in close con- tact with the under side of 1 ) the drum e, e, seen best ia "'^ fig. 1032. The several parallel layers of paper to be cut, being passed between the drum «, and the endless felt c, will be drawn off their respective reels, and fed into the machine, when- ever the driving-band is slid from the loose to the fast pulley upon the end of the main shaft /. But since the progressive advance of the paper-webs must be arrested during the time of making the cross cut through it, the following apparatus becomes neces- sary. A disc g, which carries the pin or stud of a crank t, is made fast to the end of the driving shaft /. This pin is set in an adjust- able sliding piece, which may be confined by a screw within the bevelled gra- duated groove, upon the face of the disc g, at vari- able distances from the ax- is, whereby the eccentricity of the stud », and of course the throw of the crank, may be considerably varied. The crank stud t, is connected by its rody, to the swinging curvilin- ear rack fc, which takes into the toothed wheel /, that turns freely upon the axle of the feed drum e, e. From that wheel the arms m, m,rise, and bear one or more palls n, which work in the teeth of the great ratchet wheel o, o, mounted upon the shaft of the drum e. The crank-plate g being driven round in the direction of its arrow, will communi- eate a see-saw movement to the toothed arc k, next to the toothed wheel / in gearing with it^ and an oscillatory motion to the arms m, tn, as also to their surmounting pall n. J In it, «.mg to the left hand, the catch of the P^'' 'T'll ''^^riay hoKh^^ ^ rf the ratchet wheel o ; but in its return to '"ejig'.t hand .1 W'" »». ''°''' ^^^ , ^ Tnd pull Ihem, with their attached "l"^';^.";™^/^,'^;' °Jat te *us d«wn forwari at naner in close contact with the under halfol »''«.^™" ""'°* 7.~'„j,„s felt, and iu SSTr^als, fron, the reels, by the friction between -Js surfece and *^fdl%s 'e t, %^^^ lengths corresponding to the arc of ^'^.™''°""'ttae when the swingarc is making iU lengths transversely 'ibrough .n^a-;"- ^tftTvl tt slopesTrhe ratchet teeth o. inactive stroke, viz., when it is s'"""* ",; '„ ,„ ,.,. dis,.„ce of the crank stud t, from The extent of to vxbr^^^^^^^^^ I'^t^T^^fe.le^i of the oscillations the centre/, of the plate g,becaus^ ^^ ^^^^ ^^^^ ^^^^ ^^^ f^ of the curvilinear rack, and that «» tnejoj .^^ ^^^^^^ ^.^^ ^^^ ^^^ forwards to the ^n^fe apparatu . 'H^^^^^ . ^^^ ^ ^^ ^^^ ^^^^.^^ ^^^^ ^ hears above described "^^I^^J^^^sS the wf^r ,, in its revolution with the shaft/, lifts the r, r, whose under ^ade J/s ftxed, tne w^^^^^ mo%eable blade v (as shown m toil of the lever /, consequently depresses uie ^ obliquely, like a pair of scissors, fig. 783), and slides ^^^^^^"^^^^^^^^^^^^ before the shears begin to 80 as to cause a clean cut afTO^V^e pues oi j ai j ^^^ ^^^^ .^ ^^^ operate, the transverse board u descends to press the paper wu | ^ ^^^ ^^ upon the bed r. During the action pf^he upper bla^ bell-crank bStrd u, is suspended by a cord P*^^;"|,\"^^^\PJ^X^^^^^^ bell-crank t, lever /, t Whenever the ^f ^ --^^^^^^^^^^^ board «, to be the weight *> ^""- "^J^,^\r^^^^ paper, which is regularly brought for- moved up out of the way of the next len m "» J {^ ' ^ j^j j f t^e shears s!:5i?^afa?;*^ri°^-Stfj:g'uirpSc^4^^^^^ •"^'a^ER-HANGINGS, callM more vro.^^^yJ^^^^'^^^J^P^: i^thinl'^ art of making paper-hangings, p<.p«r "^.''"^"'^^^^.."PxhrEnUh first imported among whom it has been practised from time 'mmemonal. ' »^ ^-^S^ ^^J^^^ ^ and b'egan to imitate the Chinese Papej-haa?'"?^! „„ ' e^"^^ '"« ll"' «^^^^ high excise duty upon the manufacture, Jh^J »^™ ""' S"' j " Unchecked by taxation, of refinement which the French genius ''»l,b/„=" ,?"^^'^/^,i°' 7"„^^^^ i„ /„ extended The first method of making this paper was stencil ing • "^ '"^'21 "^^ jevices, and applj- rtate, a piece of pasteboard having spa«s <="' »"' f ^^™^ ^"t^ari wi h other*^^'- ing different water co ors wrth '^e brush Anothcrj^eo^ pasteDo ^^^ ^^^^ "ta^rritrngings may be mstinguished into two classes, 1 ^^^:'^^,;^^, ^:it::i a: 't ": \?d\^.rosf Trch'tL'^ns areZmed^b, foreign maU to«'ether: or a Fourdrinier web of paper should be taken. i^Voc t^;,.Vpn«l with 4 Lading the grounds, is done with earthy colors or colored lakes thickened with ^'V::':^^^^^^^ or two chiWren, can lay the grounds of 300 pieces in a ^av The nieces are n^w suspended upon poles near the ceiUng, m order to be dried &' ar^^AcnTolirup and carried to the apartment where they are polished, by l^ing J^\Zn a 'moo h tabre, with the painted side undermost, and f "fed with the T«hsh« PicciC^ided to be satined, are grounded with fine P'^ns P^^f^ ^'Jf'ead of Sparush white . and are not smoothed with a brass polisher, but with a hard ^J^^sJ ^^^.f hh Se loi-*^ onYof the swing polishing rod. After spreading the piece "Pon the table wUh SeC^led side undermost, the paper-stainer dusts the upper surface with finely pow- dered clSk of Brian^on, commonly called talc, and rubs it strongly with the brush. In this way the satiny lustre is produced. THE PRINTING OPERATIONS. Blocks about two inches thick, formed of three separate boards glued togeAer of whicHwo are made of poplar, and one (that which is engraved) of pear-tree or sye. 326 PAPER-HANGINGS. PAPER, MANUFACTURE OF. 327 i ] t ■J n more, are used for printing paper-hangings, as for calicoes. The gram of the upper layer of wood should be laid across that of the layer below. As many blocks are re- quired as there are colors and shades of color. To make the figure of a rose, for example, three several reds must be applied in succession, the one deeper than the other, a white for the clear spaces, two and sometimes three greens for the leaves, and two wood colors for the stems ; altogether from 9 to 12 for a rose. Each block carries small pin points fixed at its comers to guide the workman in the insertion of the figure exactly in its place. An expert hand places these guide pins so that their marks are covered and concealed by the impression of the next block ; and the finished piece shows merely those belonging to the first and last blocks. In printing, the workman employs the same swimming-tub apparatus which has been described under block printing (see Calico-printing), takes ofl" the color upon hij blocks, and impresses them on the paper extended upon a table in the very same way. The tub in which the drum or frame covered with calf-«kin is inverted, contains simply water thickened with parings of paper from the bookbinder, instead of the pasty mixture employed by the calico-printers. In impressing the color by the block upon the paper, he employs a lever of the second kind, to increase the power of his arm, making it act upon the block through the intervention of a piece of wood, shaped like the bridge of a violin. This tool is called tasseau by the French. A child is constantly occupied in spreading color with a brush upon the calf-skin head of the drum or sieve, and in sliding off the paper upon a wooden trestle or horse, in proportion as it is finished. When thb piece has received one set of colored impressions, the workman, assisted by his little aid, called a tireur (drawer), hooks it upon the drying-poles under the ceiling. A sufllicient number of pieces should be provided to keep the printer occupied during the whole at least of one day, so that they will be dried and ready to receive another set of colored im- pressions by the following morning. All the colors are applied in the same manner, every shade being formed by means of the blocks, which determine all the beauty and regularity of the design. A pattern draw- er of taste may produce a very beautiful efl'ect. The history of Psyche and Cupid, by M, Dufour, has been considered a masterpiece in this art, rivalling the productions of the pencil in the gradation, softness, and brilliancy of the tints. When the piece is completely printed, the workmen looks it all over, and if there be any defects, he corrects them by the brush or pencil, applying first the correction of one color, and afterwards of the rest. A final satining, after the colors are dried, is communicated by the friction of a finely polished brass roller, attached by its end gudgeons to the lower extremity of a long swing-frame ; and acting along the cylindrical surface of a smooth table, upon which the paper is spread. The/ondtt or rainbow style of paper-hangings, which I have referred to this place m the article Calico-printing, is produced by means of an assortment of oblong narrow tin pans, fixed in a frame, close side to side, each being about one inch wide, two inches deep, and eight inches long ; the colors of the prismatic spectrum, red, orange, yellow, green, &c., are put, in a liquid state, successively in these pans ; so that when the oblong brush a, b, with guide ledges a, c, d, is dipped into them across the whole of the . 1034 parallel row at once, it comes out impressed with the different colors ^iTTr7~fJT^ at successive points e, e, «, e, of its length, and is then drawn by the WWfcriai ' paper-stainer over the face of the woollen drum head, or sieve of the * • • • swimming tub, upon which it leaves a corresponding series of stripes in colors, graduating into one another h'ke those of the prismatic spectrum. By applying his block to the tear, the workman takes up the color in rainbow hues, and transfers these to the paper. /,/,/,/ show the separate brushes in tin sheaths, set in one frame. At M. Zuber's magnificent establishment in the ancient ch&teau of Rixheim, near Mulhouse, where the most beatiful French papiers peints are produced, and where J was informed that no less than 3000 blocks are required for one pattern, I saw a two. color calico machine employed with great advantage, both as to taste and expedition. Steam-charged cylinders were used to dry the paper immediately after it was printed, as the colors, not being so rapidly absorbed as they are by calico, would be very apt to spread. The operations employed for common paper-hangings, are also used for making flock paper, only a stronger size is necessary for the ground. The flocks are obtained from the woollen cloth manufacturers, being cut off by their shearing machines, called lewises by the English workmen, and are preferred in a white state by the French paper-hanging makers, who scour them well, and dye them of the proper colors themselves. When they are thoroughly stove-dried, they are put into a conical fluted mill, like that for making snuff, and are properly ground. The powder thus obtained is afterwards sift- ed by a bolting-machine, like that of the flour mill, whereby flocks of different degrees of fineness are produced. These are applied to the paper after it has undergone all tht I „nal prinUng opei^Uons.. Upon the -".^^.^^^^"^^^^^^^^ ^^fe 'J^^tu ing table, a large chest is placed for recemng the flock I^^*^^*^ ' ^ f^^^ 15 ^ 18 feet long two feet wide at the bottom, three feet and »/^^f J'/^^P' ^f„ This chest is inches deep. It has a hinged lid. Its bottom is made o[JJ!J^^^^^^^ ieL above called the drum ; it rests upon four strong feet, so as to stand from Z4 to zo 1 'VhrblocU which serves .o apply the .^he.ve •'^.t* ^^^S^^^il - The French workmen caU <-^^ '-r'r\^''^'Z%- J^^r^^^rcJ^^s are, and is covers the inverted swimmmg tub, in the same -way a» w c writers) The spread with a brush by the tireur (corruptly styled fearer by ^ome Enghsh ^^«^^ ^ ^^ workman daubs the blocks upon the mordant, spreads ^^^^P^^;;^^^;^'^^;;^ ^ brush, and then applies it by i^-J^W ^raTra\^^^^^^^^ the paper has been thus <=?^e][ ^d, the child draws it a on 1 | ^ ^^ ^^^^^^ the flock powder over it with his hands ; »«* when Ven^in o < '^ ^ J ^ It up within the drum, and beats upon the calf.^^^^^^^^ a cloud of flock inside, and to make it cover the P'^^P^^^fJJ^; "°" . .k ^:^^., j^ order to He now lifts the lid of the chest, inverts the paper, and beats its back li.hVV, detach all the loose particles of the woolly Po^^er- .^^ everywhere of the By the operation just described, the ^^l^'^^-down being ^^J J'^^^t.^ueed to same color, would not be agreeable to the eye, ^/^^/^f^X l^L^r^^^^^ folds relieve the'pattern. To give the effect of drapery, f^J^^^f ^P^"'?^,^^^^^^^ must be introduced. For this purpose, when the piece is Perfectly dry, "»e wo Sretches it upon his table, and by the ^.-d--/,^;.^^^^^^^^ Xd^^ ^ "^^^oWrfTap'^iic^ upon the above monlant, when nearl^^^^^^^ proper eold size ; and the same method of application i^ resorted ^^^^^ ^«^J''y ™ ^^ gilding of wood. When the size has become perfectly hard, the supertluous goia le is brushed off with a dossil of cotton wool or fine linen. The colors used by the paper-hangers are the foUowins :— ^.^,,,„ „r the two 1. Wfntes. These are either white-lead, good whitening, or a mixture ^^ /^^^f' 2. Yellmvs. These are frequently vegetable extracts ; ^^J^^^^^fj^^'^fc^^ltlX^ or Persian berries, and are made by boiling the substances ^ith water. Chrome yeuow is also frequently used, as well as the terra di Sienn« and yellow ochre. 3. Reds are almost exclusively decoctions of Brazil wooo. 4. Blues are either Prussian blue, or blue verditer. couDer: 5. Greens are Scheele»s green, a combination «f «^«"^°"^,,f "V^^e^ Jnd yellow?^ the green of Schweinfurth, or S-en verdUer ; as also a m^^^^^^^^ 6. Violets are produced by a mixture of blue and ^^^^Uh^nxL may be obtained directly by mixing a decoction of l<>f,^°??^^f ..^l^- ^^^^^^ ^ either common ivory or Frankfort black ; and grays are loruicu uj u^^ ^'"illTe"^^^ rendered adhesive and consistent, by being worked up with gelatinous siztra'w^lrsoK^^^^^^^ liquefied in a kettle. Many ^tjie color^^^^^^^^ thickened, however, with starch. Sometmies colored lakes are employed. bee ^VTpER, MANUFACTURE OF. ^Papeterie Fr. ; P<'P^'!l''^^^l.^^^ This most Useful substance, which has procured for the moderns an "^f^^j^^^^^^^J^^^f ^^^^^^ over the ancients, in the means of diffusing and P«n>etuatingknowk^e seems to hav^ been first invented in China, about the commencement of ^^e Chnstian era and was thence brought to Mecca, along with the article tself, about the ^^f'^? ^^^^^.^^^ century; whence the Arabs carried it, in their rapid career of conquest «^"d colonizati^, to tht coasts of Barbary, and into Spain, about the end of the 9th or begmnmg of the '^Vorer"" accounts, this art originated in Greece, where it was first made f^^ cotton fibres, in the course of the tenth century, and continued there ^V^PJ^^J.^^^J^^^^^^ the next three hundred years. It was not till the beginning of the J^th century that paper was made from linen in Europe, by the establishment ^^ f P*f ""^arU 1390, al Nuremberg in Germany. The first English paper-miU ^»f ,%^^^^^^J f^" ford by a German jeweller in the service of Queen Elizabeth about the >ear 158^ But the business was not very successful ; in consequence of ^.»^ich for a lon^ penod afterwards, indeed till within the last 70 years, this <^«««t'T^.„^Y'Lte LiS Ught ^ writing pal>er8 from France and Holland. Nothing places m a more stnkmg UgM ine 59 '--v 9m PAPER, MANUFACTURE OF. '] t«st improvement which has taken place in all the mechanical arts of England since the era of Arkwri^ht, than the condition of our paper-machine factories now, compared with those on the Continent. Almost every good automatic paper mechanism at pre&ent mounted in France, Germany, Belgium, Italy, Russia, Sweden, and the United States, has either been made in Great Britain, and exported to these countries, or has been con- structed in them closely upon the English models. Till within the last 30 years, the linen and hempen rags from which paper was made, were reduced to the pasty state of comminution requisite for this manufacture by mashing them with water, and setting the mixture to ferment for many days in close vessels, whereby they underwent in reality a species of putrefaction. It is easy to see that the organic structure of the fibres would be thus unnecessarily altered, nay, frequently destroyed. The next method employed, was to beat the rags into a pulp by stamping tods, shod with iron, working in strong oak mortars, and moved by water-wheel ma- chinery. So rude and ineffective was the apparatus, that forty pairs of stamps were required to operate a night and a day, in preparing one hundred weight of rags. The pulp or paste was then diffused through water, and made into paper by methods similar to those still practised in the small hand-mills. About the middle of the last century, the cylinder or engine mode, as it it ^lled, of comminuting rags into paper pulp, was invented in Holland ; which was soon aAerwardi adopted in France, and at a later period in England. The first step in the paper manufacture, is the sorting of the rags into four or five qualities. They are imported into this country chiefly from Germany, and the ports of the Mediterranean. At the mill they are sorted again more carefully, and cut into «hreds by women. For this purpose a table frame is covered at top with wire cloth containing about nine meshes to the square inch. To this frame a long steel blade is attached in a slanting position, against whose sharp ed^e the rags are cut into squares or fillets, after having their dust thoroughly shaken out through the wire cloth. Each piece of rag is thrown into a certain compartment of a box, according to its fineness; seven or eight sorts being distinguished. An active woman can cut and sort nearly one cwt. in a day. The sorted rags are next dusted in a revolving cylinder surrounded with wire cloth, about six feet long, and four feet in diameter, having spokes about 20 inches Ions, attached «t right angles to its axis. These prevent the rags from being carried round with the case, and beat them during its rotation ; so that in half an hour, being pretty clean, they are taken out by the side door of the cylinder, and transferred to the engine, to be first washed, and next reduced into a pulp. For fine paper, they should be previously boiled for some time in a caustic ley, to cleanse and separate their filaments. The construction of the stuff-engine is represented in ^g«. 1035 1036 Fig. 1035 is the lon- Q \\ q gitudinal section, and fig, *^^^ Sbg' ^y ^ fj?i^&^ o V ^^ V lOBfi the plan of the engine. .SKC: // -r^^^aa \\^*==5;^ _^ 'Yhe large vat is an oblong cistern rounded at the an- gles. It is divided by the pari tition i, 6, and the whole in- side is lined with lead. The cylinder c, is made fast to the spindle d, which extends across the engine, and is put in motion by the pinion ;>, fixed to its extremity. The cylinder is made of wood, and furnished with a num- ber of blades or cutters, secured to its circumfer- ence, parallel to the axis, and projecting about an V\ ■I" j//^ ^^^^ above its surface. ^^V ^| I I I II I .J^yy Immediately beneath the ^-— — — \n , ^ u iBe — 11 1 ^ — -y cylinder a block of wood k is placed. This is mounted with cutters like those of the cylinder, which in their revolution pass very near to the teeth of the block, but must not touch it. The dis- tance between these fixed and moving blades is capable of adjustment by elevating or depressing the bearings upon which the necks e, «, of -Jie shaft are supported. These kearings rest upon two levers g, g, which have tenon? at their ends, fitted into upright •ortises, made in short beams A, A, bolted to the side£ of the engine. The one end of PAPER, MANUFACTURE OF. 329 1037 the levers g. g, is moveable, while the other end is adapted to nse an^^^" ;»P<>» ^^ n the beam;? A, as centres. The front lever, or that nearest to the^>^;;^^,^;;^^^^^ bleof being elevated or depressed, by turning the han^^^of * s^^^^^^^^^ view), which acts in a nut fixed to the tenon of g and comes Hf^^Xasses are let into cutters in the block and those in the cylinder. ^cx^^rA^ «nd covered with rn Tu 1 r. u A ^c i 4;, inq^iU a circular breasting made of boards, ana covereu wim she^et le\Vf lttl?:^^o^ fiUbe^ very -^^^^^^ '^::^J^s:'Z^ tween the teeth and breasting ; at its bottom, the lo^ . ^^^f;^2't^^::^i::il^^, t^ l^ rhS brS?inT\n pwitS riSer cases a flannel bag is tied round the nose "^ l^e stopcock, to act as a filter ^^^ ^^^^^ The rags being put into ^^^ ^^me ^^^^^^ they are torn into the finest fila- Of the <=yl'"der between the two sets o^^^^^^^^^ y ^^^ ^^ ^^^ ^^^^^^j^^ ments and by the »?P"1^^« J^"^ '^^."t^ ^^^^^^ ^als and water are ,^ised into that part upon the inclined P!j^^^-^^„^J/„,f ?f ^he fiqui^^ to maintain an equilibrium, puts the whole ^on^enfs^S the ttem n^^^^^^^ dow'n the inclined plane, to the left hand of . and contents oi ^"f. ?'^^^Y . " pp th«» arrow) whereby the rags come to the cylinder again in jr';': o7 ar«" ^''inuus: rrJ' ther:r J repeat^U.,. dra.n ou, and separa.«i ia ''^^:^^^^^^^^:^> SyTurr; otr ^hl-rags in the engine, causmg .hL ;„ be nrSenlerto the cutter a different angles every time; otherwise, as the r;2.L of ?l" :;^^^^^^^^ IT/i^^-^^^^^^^ teeth of the cylinder c itself are set the axes 01 the cyimaer, ^^^^^^^ j^s^ ^^.^^ therefore the cutting edges meet at a small angle, and come in contact, first at the one end, and then towards the other, by successive degrees, so that any rags coming between them, are torn as if between the blades of a pair of forceps. Sometimes the blades fe m the block are bent to an angle in the middle, instead of being straight and ■ inclined to the cylinder. These are called elbow plates ; their two ends being inclined in opposite directions to the axis of the f^f^'J^'^'^^^^l the ed-es of the plates of the block cannot be straight lines, but mu^t be curved to adapt thPrnselves to the curve which a line traced on the cylinder will necessarily have. The Sat^ orblaSes areTnlted by screwing them together, and fitting them into a cavity cut piaies or mauess "^ "»" J wlaes are bevelled awav upon one side only. ""^ "hrktSin'its JtcTbft:i,^^^deLetai>«.,a''nd truly ^fJ^^^^^^Z nf the cistern so that the water will not leak through Us junction. The end ol it comes lou^^h tte woc^wodc of the chest, and projects to a small distance on its outside bemg kept in its place by a wedge. By withdrawing this wedge, the block becomes loose and can be removed in order to sharpen the cutters, as occasion may be. This is done at a grindstone after detaching the plates from each other. , - . ,. . ^ The cutlers^ the cylUider are fixed into grooves, cut in the wood of the cylinder, at equal d stances asunder, round its periphery, in a direction parallel to its ax.^ The number of these grooves is twenty, in the machine here represented. For the i^a.A«- each groove has two cutters put into it; then a fillet of wood is driven fast m between then^ fo hold them firm ; and Ihe fillets are secured by spikes driven into the solid wood of the cylinder. The beater is made in the same manner, except that each groove contains three *"lnthe operation of the cylinder, it is necessary that it should be enclosed in a cas«^ or It would throw all the water and rags out of the engine, in consequence of its great velocity. This case is a wooden l)ox m, m, fig. 1035 enclosed on every sjde except the tottom- one side of it rests upon the edge of the vat, and the other upon the edge of the nartilion 6, 6, /i?- 1036. The diagonal lines m, r, represent the edges of wooden frame^ whi'a^e cohered with hair or wi. e^loth, and immediately behind these the box is furnished With a bottom and a ledge towards the cylinder, so as to form a complete trough. The rauarc fi-ures under n, n, in /ig. 1035 show the situation of two openings or spouU through the side of the case, which conduct to flat lead-pipes, one of which is seen near the upoer g in H- 103« placed by the side of the vat ; the beam being cut away from Ikm. ThSe fri waste pipes to discharge the foul watet from the engine ; because tb« ft 330 PAPER, MANUFACTURE OF. PAPER, MANUFACTURE OF. Ml I cylinder, as it turns, throws a great quantity of water and rags up against the sieves i the water goes through them, and runs down to the trough under n, n, and thence into the ends of the flat leaden pipes, through which it is discharged. o,o,^g. 1056 are grooves for two boards, which, when put down in their places, cover the hair sieves, and stop the water from going through them, should it be required in the engine. This is always the case in the beating engines, and therefore they are seldom provided with these waste pipes, or at most on one side only ; the other side of the cover being curved to conform to the cylinder. Except this, the only difference between the washing engine and the beater, is that the teeth of the latter are finer, there being 60 instead of 40 blades in the periphery; and it revolves quicker than the washer, so that it will tear out and comminute those particles which pass through the leeth of the washer. In small mills, when the supply of water is limited, there is frequently but one ensine. which may be used both for washing and beatin?, by adjusting the screw so as to let the cylinder down and make its teeth work finer. But the system in all considerable works, is to have two engines at least, or four if the supply of water be great. The power re- quired for a 5 or 6 vat miU, is about 20 horses in a water-wheel or steam engine. In the above figures only one engine is shown, namely, the finisher ; there is an- other, quite similar, placed at its end, but on a level with its snrface, which is called the washer^ in which the rags are first worked coarsely with a stream of water, running through them to wash and open their fibres ; after this washing they are called half. »tvff, and are then let down into the bleaching engine, and next into the beating engine, above described. By the arrangements of the mill gearing, the two cylinders of the washer and heater engines make from 120 to 150 revolutions per minute, when the water-wheel moves with due velocity. The beating engine is always made to move, however, much faster than the washing one, and nearly in the ratio of the above numbers. The vibratory noise of a washing engine is very great ; for when it revolves 120 times per minute, and has 40 teeth, each of which passes by 12 or 14 teeth in the block at every revolution, it will make nearly 60,000 cuts in a minute, each of them sufficiently loud to produce a most grating growling sound. As the beater revolves quicker, having perhaps 60 teeth, instead of 40, and 20 or 24 cutters in the block, it will make 180,000 cuts in a minute. This astonishing rapidity produces a coarse musical humming:, which may be heard at a great distance from the mill. From this statement, we may easily understand how a modern engine is able to turn out a vastly greater quantity of paper pulp in a day than an old mortar machine. The operation of grinding the rags requires nice management. When first put into the washing engine they should be worked gently, so as not to be cut, but only powerfully scrubbed, in order to enable the water to carry off the impurities. This effect is obtained by raising the cylinder upon its shaft, so that its teeth are separated considerably from those of the block. When the rags are comminuted too much in the washer, they would be apt to be carried off in part with the stream, and be lost ; for at this time the water-cock is fully open. After washing in this way for 20 or 30 minutes, the bearings of the cylinder are lowered, so that its weight rests upon the cutters. Now the supply of water is reduced, and the rags begin to be torn, at first with considerable agitation of the mass, and stress upon the machinery. In about three or four hours the engine comes to work very smoothly, because it has by this time reduced the rags to the state of half-stuff. They are then discharged into a large basket, through which the water drains away. The bleaching is usually performed upon the half -stuff. At the celebrated manu- factory of Messrs. Montgolfier, at Annonay, near Lyons, chlorine gas is employed for this purpose with the best effect upon the paper, since no lime or muriate of lime can be thus left in it ; a circumstance which often happens to English paper, bleached in the washing engine by the introduction of chloride of lime amon? the rags after they have been well washed for three or four hours by the rotation of the engine. * The current of water is stopped whenever the chloride of lime is put in. From 1 to 2 pounds of that chemical compound are sufficient to bleach 1 cwt. of fine rass, but more must be employed for the coarser and darker colored. During the bleaching oper- ation the two sliders o, Oyfig. 1035 are put down in the cover of the cylinder, to prevent the water getting away. The engine must be worked an hour longer with the chloride of lime, to promote its uniform operation upon the rags. The cylinder is usually raised a little during this period, as its only purpose is to agitate the mass, but not to triturate it. The water-cock is then opened, the boards rw, m are removed, and the wash- ing is continued for about an hour, to wash the salt away ; a precaution which ought to fce better attended to than it always is by paper manufacturers. The half-stuff thus bleached is now transferred to the beating engine, and worked into a fine pulp. This operation takes from 4 to 5 hours, a little water being admitted from time to time, but no current being allowed to pass through, as in the washing engine 1 The softest and fairest water should be selected for this purpose; ^^^^^ V*'*'?!!^ ^^ ministered in nicely regulated quantities, so as to produce a proper spissitude ol stun tor ""rir^priS paper, the sizing is given in the beating engine, towards the end of ite operation. The size is formed of alum in fine powder, ground up ^/^^^/^l' /* J,"^ mixture about a pint and a half are thrown into the engine at mtervals, during the last half-hour's bealin?. Sometimes a little indigo blue or smalt is also a^^ed when a peculiar b.oom color is desired. The pulp is now run off into the stuff c^^st, wnere The different kinds are mixed; whence it is taken out as wanted. The chest »« usual J a rectangular vessel of stone or wood Uned with lead, capable of ^^"taining 300 cubic feet at least, or 3 engines full of stuff. Many paper-makers prefer round chests, as they •"^t: r7pef rmaie in single sheets, by hand labo. as in the older establish- ments, a small quantity of the stuff is transferred o the ^«'^^/"nn?p^n? xvL abours and there diluted properly with water. J»»'^/^/. ^^ ^ ^f f ^^/f. ^l^^^^,^^^ feet square, and 4 deep, with sides somewhat slanting. Along the op of the ^ a a Iward is laid with copper fil ets fastened len-thwise upon it, to make the mould slide more easU abn..^ T^^^^ the bridge The maker f "'^^-^ ^^ ,f/ ^^^e has to his left hand a smaller board, one end of which is made fast to ^^^ ^"^f ' ^^^^^^^ the other rests on the side of the vat. In the bridge opposite to this, a nearly upright "f wo^, caUeli the ass, is fastened In the vat ^here is a ^PP^^^^lJ^^^^^^^^ Sates with a steam pipe to keep it hot ; there is also an agitator, to maintain thg stutt m ' T^TouTirS-of frames of wood, neatly joined at t^e corners wUhw^^^^^^ running across, about an inch and a half apart. Across these, m the If ngth of the moulds the wi/es run, from fifteen to twenty per inch A strong raised wu-e »fj.»'^^^l«;?J«^^^^^^^ the cross bars, to which the other wires are fastened; this gives the laid paper its ribbed ■''5^hTwa"V.mark is made by sewing a raised piece of wire in the ^o™ «[„ ^f^^^^' ^[,*J^J figured device, upon the wires of the mould, wh ch makes ^^epaper thinner mth^e places. The frame-work of a wove mould is nearly the same ; ^" V?,!,'^^^ t 64 -^^^^^^^^ Separate wires, the frame is covered with fine wire cloth, containing ftom f t« ^^ f^s per inch square. Upon both moulds a deckel, or moveable raised edge-frame, i^ used , which must fit very neatly, otherwise the edges of the paper will »>e r«"f • A pair of moulds being laid upon the bridge, the workman puts on the deckel, brm^ the m'Luld into a vertical position, dips it about half way down into the ^tuff before lu^^^ then turning it into a horizontal position, covers the mould with the ^l^f^^^J^^^^^'^ ffentlv This is a very delicate operation ; for if the mould be not held perfectl} level, Se part of the sheet will be thicker than another. The sheet thus formed has however SSeSherence; so that by turning the mould, and ^^^^-^''^'^^^^Z^T.ZtZ^^^^ vat, it is affaii reduced to pulp if necessary. He now pushes the mould ^^n§ the smaU board to the left, and removes the deckel. Here another ^o^-k/nan called the c^uc^^ receives it, and places it at rest upon the ass, to dram off some of the water MeanwhUe the vat-man puis the deckel upon the other mould, and makes another s^^et. The coucher stands to the left side of the vat, with his face towards the vat-man pr maker^ on his right is the press furnished with felt cloths, or porous flannels ; a t»iree-inch thick plank lies before him on the ground. On this he lays a cushion of ^^^ts, ««f. ^^^^^J^ knotherfelt; he then turns the paper wire mould, and presses it upon the felt, where the sheet remains. He now returns the mould by pushing it along the bridge^ The maker has by this time another sheet ready for the coucher ; which like the pre- ceding, is laid upon the ass, and then couched or inverted upon another felt, laid down lor ^^'in^thiTway, felts and paper are alternately stratified, till a heap of six or eight qnirw is foime.l, which is from 15 to 18 inches hi-h. This mass is drawn into the pre^, and exposed to a force of 100 tons or upwards. After it is sufficiently compressed, the machine i«s relaxed, and the elasticity of the flannel makes the rammer descend (if a hy- draulic press be used) with considerable rapidity. The felts are then drawn out on the other side by an operative called a layer, who places each felt in succession upon one board, and ea:h sheet of paper upon another. The coucher takes immediate possession of the fells for his further operations. , v *c o ..oo^« in 10 Two men at a vat, and a boy as a layer or lifter, can make about 6 or 8 reams in lu hours In the evening the whole paper made during the day is put into another press, and subjectAd to moderate compression, in order to get quit of the mark of the leli, ana more of the water. Next day it is all separated, a process called parting, and being again pressed, is carried into the loft. Fine papers are often twice parted and pressed, m order to eive them a proper surface. ^ „ ii»^« The next operation is the drying, which is performed in the foUowing way. Posts ^■i! f :1 332 PAPER-MAKING MACHINE. about 10 or 12 feet hieh are erected at iHp H.c»o««^ r . ^ pierced with holes six inches apar ftwo spars w^thr^n *~/«^^'^^« ^^^ o«>er, and the distance of 5 inches from one ai^VcTed alb^^^^^^ between them, at feet high between these posts, supported bv pins nn.h^ ?r tnbbj ^ placed about 5 The workman takes up 4^8 sheKnaDera^Ti.K"^'' ^^^ ^""^^^ ^ ^^^ P«sts. the form of a T; pas4g this T betwLn tKSlTsMr.il'P^^u" * ^'^^^ *^^ ^^ « proceeds thus till all the ropes are fu^ He then^'iilJhf 't m '^^'? "P*^" '^^"^^ "»<» Its place, which he fills and raises L liki manner N op nr f ^'^^b ^""^ P"»« «"«ther in set of posts. The sides of ihedryhig^^Zha^^^^ '''^^^' f'^ PJ«<^«i in every any angle at pleasure. ^ P"'^^^ shutters, which can be opened to is ^d^V' -e^eroT^^^^^ ^f, »r^ - heaps to be sized. Size other matter containing much Jitinp THpS u? **""^"- ^' ^'^^ep's feet, or any jdly ; to which, when"strr4 itmX Jnt y of aCls" a^ed^^'^ie "" T'^' l^ ^ takes about 4 quires of paoer snreads ihpm nnV ;„ tki • added, ihe workman then taking care that they be^XllSene^^^ Th s is ratheTar^'"^^ '^^'"^^^ ^'^^^ ^^^^'^ fluous size is then Pressed'out,'andirp;per'^? ^ar "J" nto s^^^^^^^ 3'^^"^^'" more pressed, it is transferred to the dry no.room hi,t mnct « ? I" f"-/ ^'"^ «n<^« Three days are required for this vur^J Whl^ThL • ^ v"*"^ ^ "^""^ ^^o ^u'ekly. to the finishing-h^use, and^ agah^^^^el^ed It'y iard'%' i^f th "'""^f l!, 1!-^' ^' »^ ^""«» •mall knives, in order to take out thp S^ J . V'^ ^**^" ^'^^^d by women with Ihese reams are comoressed tied nn nnH coot *^tu ^""'"«« "»io reams, and done up, can count 200 reams, orT^SoJ) sheeK a L J ^""'''"'^ '"' '°^'- ^ ^^«^ ^"^''"^^ boa^r3l,XZJ^;aTd"ttwLn'^^^^^^^ ^^^L^^^ ^^^^^^ P-*- ju^ecting the pilJ'to the ^es.^^"T^- rmu^i^^at: tZt ^^j^^^ orltn^rilffibK^ott'ei^^^^^^^^ ^^^^ - too much used, differently raised, and that on whicM^^^^^^ two sides of the felt are' are laid down. As the felts have to ZliTZ 1% .S'^ « applied to the sheets which should be made stoutf ^long combed ^^^^^ warp should be of carded wiol and sniTintn 7^A !u , " *^'^*^- ^he woof, however, and capable of imblbrng iuch water * '"" '^'^^' ^ *^^ '^ '^"^" '^^ ^-^^^^ ^Pon^: T^i^Z^^^^^ r •*« <^i paper by hand, has fo, duces it in a continuous sheetTf inS teTnatrw V^?^"'S ^^^ a machine which pro- sizes, by the PAPEK^xTTrLrMACHiNE ° ''^ '' afterwards cut into suitable triv^edTL^iTi^niftot?;;^^^^^^^^^^ r/a'cT'^ ^' ^^^^""^ - ^--' -- it a patent for 15 years, wiS a sum of 8000 ?Sn l r *^°" i""?,"^ "?»««> ^nd obtained for ward for his ingenuity. ' The spSS^catio^of iTlflT '^^ .^f^"!? ?<>^ernment, as a re- of Brevets rf' lyfventum exvirl MT^^^rV a . '11^"^'? Published in the second volume Robert's machine ZS fof^mOf^l'\'^Z ^^^.^^ ^he said works, bought insUtut"ed" a'laJ^;u^; a'it e o^Trfd'ltst!;^^ ht ^'l^^f r *^. ""^"^^^ ^^^ ^a«« June, 1810. Didot then sent ovpr {Tpf? .k S ' P*^^"' ^^ " decision dated 23d which contained Te specificat^^^^^^ Repertory of Arts, for Sept. 1808, secure the improved Machine 3e'^^^^^ T^ instructions to a friend to obtained, but became inopemtive In c^iou^ncJ ^f^f ff l^"^'. '^^^ P"*^"* ^^ France, as he had promiJS so as to mo^t Thp n5 f' ^^ u?'^*'^ '^"^"^ *« 'etum to required by the French Tatent law. It was not IS m^Tv. T'it' V'^ ^^« ^^^^ maker at Paris, constructed the n«npr ,LTrot \ ^^^S.that M. Calla, machine- Fourdrinier's, and whS ^ the l^nhlu^Tf^' n- ^^ "^. ^"^'^"^ ^^ ^^e name of imperfect in comparS' of «n Pn.r i, ^ I *^ ^ichannaire Techvolo^ique, was very France. La cneehanisa. ,h.. .h. It deserves parucaianyio ^ , received gold medals at the last ejposi- ra'';f thr'plpen" t Z LouvCaad all the res, received medals either of sUver o, ""The following is a true narrative of the rise and progress of the paper automaton. M LeirDidJt, aeeompanied by Mr. John Gamble, an EnsUshman ,vho had resded M. L,e-er uiuoi, "^^,. '^„i,,|„^' „ermis«ion from the French government, m 1800, to for several years m P»"^. »^'»^^ „Kbert " continuous machi«, with the view of geU S,7thr^iefit of Ksl^^.\X and meehanicri skill to bring it into an op«a..ve su..« ting the benent f' P;"'"' J; , r ,^^ vigorous development of this embrjo project, ICh'tlZved an atoSntn France, they addressed themselves, on the one hand^u> :™lTrm'e;:at opulent and public spi^Hed and on ^e^-J^e.'o -.-. di. jinguished for pe-verh^ -JX^^^^ ctrtaS' iCprovrnis upoi. HH£"^.^fa5h^5at« o?«tlt t i*tjrn^?a.r^';r'u;o- %re'p™prre*!S*"showed good reasons, ia the enormous «pense of their experiment^ •nd theTajrnaUmportancf of the object, why ^^Pa'cnt should h*ve been «^endl" years from the latter date, and would have obtained juf^e from P""^*^*"* "J.'^',' "^J^^ hnt fnr an unvTorthv artifice of Lord Lauderdale in the House o( J^ords. ne, ana nn "We will give seven years, and Mr. Fourdnni^ may app y a^^^^^^^ ^^^^^^^^ S! .Wp in the natent to which he was entitled under the act of parliament. mrtfoid in^K^^^^^^ long conspicuous as the seat of a good manufactory of wer and paper moSSs, was selecteS by the proprietors of the patent as the fit est nW for realizin- their plans ; and happily for them it possessed, in Mr. HaU's engineer- KstSS every tool equisite for constructing the novel automaton, and m his ^4tanrMr B«?an Donkin, "young and zealous mechanist, who combining pm.ision ;?workmanship^with fertilit; of invention, could turn ^^^ l°f ^-.^I^^^i^^^^^ account. To this gentleman, aided by the generous ?«"fif.^^;y^^^j"^^S;i„^^^ the dory of rearing to a stately manhood the helpless bantling of M. L. Didot »s entirely due i^ ml aft?r nearly three years of intense application, he prc^uced a self-acting aS^hine for making an endless web of paper, which was erected at St, Neot's under the S^eri^tende^:e of Mr. Gamble, and performed in such a manner as to surprise every ^'l^ncrihat important era Mr. Donkin has steadily devoted his whole mind and meant . Rapport de Urj Centr.1, par M. Le Baron Cl»«le» Djjpin v^^^^ ^^^^ ,^, ^^ p^ t See thit shabby piece of diplomacy unveiled in the Minutes otEviacnnc w^ nittM of the House of Commons on Fourdnmer's patent ; Ma> , IM/. K. ?f ■m^' 334 PAPER-MAKING MACHINE. to the progressive improvement of this admirable annamtiic . ««.i »,-« v ♦!. i . --cularity, precision, promptitude, and vr^Zctivenes^^^! ' v ^»«» ^J t^^ unfailmf place along with wif, W^gewo^dTand^^kwS^^^^^^ ^^S ^^^'^ • "La France" says a late official eu]ZiJnfhL^ ? ^^ ^ of mechanical fame. ments, «ne craint p^lus la r vali^ des au rl'luplernoTA^^^^^^ '"''V'^'T ^^ ^'' ''""^ de papiers et de cartons «• A ftlr t k:. i r^^^^ P*Vi ^^ fabrication des divers genres diafe.' co„f:^'=rhTr,823l!Jrer.^Ss:ssTo"^^^ W" con/e„u, containing one of the Fourdrinier machines made a^ tIh I JJ of the ^a;n«- papers possess many advantages : they can receive, so to s^erunlirnhJ^H'"'""*'^^ they preserve a perfectly uniform thickness throughout alfthdrlSthPv""''''"^ fabricated m every season of the year ; nor do they require to be S!^' , • ^ °!f ^ ^ by M. Delalouche » aPPa^atus of Mr. Donkin, recenUy imported from England they encounter in bringing he m^hlner^ to tfthpn ? ^^'T\ ^ ""^"^^ and machine , , I Expense of 7 vats per annum (see next page) is A machine doing 7 vats' work, is, per annSn . Balance saved by the machine per annum . .£1,870 '^£^^^^rzr;:^z:^::s^:^^-^^^^v.r^^^^^uc. D:AT.x^ 112 presses, &c. ) Total 41 persons. 42 11 170 4 o'2,604 ] In the same statement, it was shown that the expense of making paper by hand is 16». per cwt whereas by their machine it is pnly 3». 9(i. ; so that upon 432,000 cwts. the Quantity'annually made in Great Britain and Ireland (as founded upon the fact that one vat can make 480 cwts. of paper, and that there were 900 vats m the kingdom), the annual saving by the machine would be 264,600/., or 345,600/. — 81,000/. In a second statement laid before the pubUc in 1807, the patentees observe that their recently improved machine, from its greater simplicity, may be erected at a considerably reduced expense. « Mr. Donkin, the engineer, will engage to furnish machines of the dimensions specified below, with all the present improvements, at the prices specified below. Inches. If driven by atraps. £ 3 or 4 vats - - • - 6 ditto . - - - 8 ditto - - - - 12 ditto - . - - 3 or 4 vats . - - . 6 ditto . - - - 8 ditto - - - - 12 ditto - - - - 30 40 44 54 30 40 44 54 between the deckles ditto ditto ditto ditto ditto ditto Ifdriven by wheels. between the deckles ditto ditto ditto ditto ditto ditto 715 845 940 995 750 880 980 1,040 « Instead of 5 men, formerly employed upon 1 machine, 3 are now (in 1813) fully safficient, without requiring that degree of attention and skill which was formerly indis- pensable. « In 1806 the machine was capable of doing the work of 6 vats in twelve hours ; it is, however, now capable of doing double that quantity, at one fourth of the expense. For by the various improvements enumerated above, the consumption of wire is reduced nearly one half, and lasts above double the time ; the quantity of paper produced is doubled ; and, taking into consideration the work which is now performed by the men over and above their immediate attendance upon the machine, it may be fairly stated, that the number of men is reduced to one half; consequently the expense of wire and labor is reduced to one fourth of what it was. « The other advantages incidental to the nature of the process of making paper by this machine, may be classed in the following order : — " 1st. That the paper is much superior in strength, firmness, and appearance, to any which can be made by hand of the same material. ** 2d. It requires less drying, less pressing and parting, and consequently comes sooner to market ; for it receives a much harder pressure from the machine than can possibly be given by any vat press, and is therefore not only drier, but, on account of the close- ness and firmness of texture, even the moisture which remains is far sooner evaporated, on exposure to the air, than it would be from the more spongy or bibulous paper made by hand. 336 PAPER-MAKING MACHINE. PAPER-MAKING MACHINE. 337 1 "The superior pressure, and the circumstance of one side of the paper passing undei the polished surface of one of the pressing rollers, contribute to that smoothness which m hand-made papers can only be obtained by repeated parting and pressing ; consequent!; a great part of the time necessarily spent in these operations is saved, and the papet sooner finished and ready for market. " 3dly. The quantity of broken paper and retree is almost nothing compared with what is made at the vats. " 4th. The machine makes paper with cold water. " 5th. It is durable, and little subject to be out of repair. The machine at Two Waters, in Hertfordshire, for the last three years, has not cost 10/. a year in repairs. " 6th. As paper mills are almost universally wrought by streams, which vary con- siderably in their power from time to time, there will result from this circumstance a very important advantage in the adoption of the machine. The common paper mill being limited by its number of vats, no advantage can be taken of the frequent accessions of power which generally happen in the course of the year ; but, on the contrary, as scarcely any mills are capable of preparing stuff for twelve vats, every accession of power to the mill, where a machine is employed, will increase its produce without any additional expense. " 7th. The manufacturer can suspend or resume his work at pleasure ; and he is be- sides effectually relieved from the perplexing difficulties and loss consequent upon the perpetual combinations for the increase of wages." It is a lamentable fact, that the attention required to mature this valuable invention, and the large capital which it absorbed, led ultimately to the bankruptcy of this opulent and public-spirited company ; after which disaster no patent dues were collected, though twelve suits in Chancery were instituted ; these being mostly unsuccessful, on account of some paltry technical objections made to their well-specified patent, by that un- scientific judge Lord Tenterden. The piratical tricks practised by many considerable paper-makers against the patentees are humiliating to human nature in a civilized and toi-disarU Christian community. Many of them have owned, since the bankruptcy of the house removed the fear of prosecution, that they owed them from 2000/. to 3000i. apiece. Nothing can place the advantage of the Fourdrinier machine in a stronger point of view, than the fact of there being 280 of them now at work in the United Kingdom, making collectively 1600 mQes of paper, of from 4 to 5 feet broad, every day ; that they have lowered the price of paper 50 per cent., and that they have increased the revenue, directly and indirectly, by a sum of probably 400,000/. per annum. The tissue paper made by the machine is particularly useful for communicating engraved impressions to pottery ware ; before the introduction of which there was but a miserable substitute. Messrs. R. and J. Clewes, of Cobridge potteries, in a letter to Messrs. Fourdrinier, state, ** that had not an improvement taken place in the manufacture of paper, the new style of engraving would have been of no use, as the paper previously used was of too coarse a nature to draw from the fair engravings any thing like a clear or perfect impression ; and the Staffordshire potteries, in our opinion, as well as the public at large, are deeply indebted to you for the astonishing improvement that has recently taken place, both as regards china and earthenware, more particularly the latter." The following rates of prices justify the above statement >— 1814. 1822. 1833. 9» d, 9, d, 9. d. Demy pottery tissue •-•-120 96 70 Royal ------ 16 3 12 89 « We have adopted a new mode of printing on china and earthenware, which, but for your improved system of making tissue paper, must have utterly failed ; our patent ma- ehlne requiring the paper in such lengths as were impossible to make on the old plan. On referring to our present stock, we find we have one sheet of your paper more than 1200 yards long. Signed, Machin and Potts ; Burslem, February 25th, 1834." I have had the pleasure of visiting more than once the mechanical workshops of Messrs. Bryan Donkin and Co. in Bermondscy, and have never witnessed a more admirable assortment of exquisite and expensive tools, each adapted to perform its part with despatch and mathematical exactness, though I have seen probably the best machine factories of this country and the Continent. The man of science will appreciate this statement, and may perhaps be surprised to learn that the grand mural circle of 7 feet diameter, made by Troughton, for the Royal Observatory of Greenwich, was turned with final truth upon a noble lathe in the said establishment. It has supplied no fewer than 133 complete automatic paper machines, each of a value of from 1200/. to 2000/., to different manufactories, not only in the United King(fom, but in all parts of the civilized world j as mentioned in the second paragraph of the present article. Each ^a »J 00 CO t* tQl »« machine is capable of making, under the impulsion of anf prime mover, all unwatched by a human eye, and unguided by a human hand, from 20 to 50 feet in length, by 5 feet broad, of most equable paper in one minute. Of paper of average thickness, it turns off 30 feet. Fi^.\0?>9> is an upright longitudinal section, representing the j machine in its most complete state, including the drying steam I cylinders, and the compound channelled rollers of Mr. Wilks, I subsequently to be described in detail. The figure in the upper [line shows it all in train, when the paper is to be wound up i wet upon the reels e, e, which being moveable round the centre U of a swing-bar, are presented empty, time about, to receive (the tender web. The figure in the under line contains the I steam or drying cylinders; the points o o, of whose frame^ *B j replace, at the points p, p, the wet reel frame, f f, p. A is the vat, or receiver of pulp from the stuff-chest. B is the knot strainei* of Ibotson (p. 841.), to cleai the pulp before passing on to the wire. G is the hog, or agitator in the vat. The arrows show the course of the currents at the pulp in the vat. I is the apron, or receiver of the water and pulp which escape through the endless wire, and which are returned by a scoop-wheel into the vat. b is the copper lip of the vat, over which the pulp flows to the endless wire, on a leathern apron extending from this lip to about nine inches over the wire, to support the pulp and prevent its escaping. c, c are the bairs which beai up the small tube rollers that support the wire. d, d are ruler bars to suppoit the copper rollers over whicA the wire revolves. K is the breast roller, round which the endless wire turns. N is the point where the shaking motion is given to tte machine. M is the guide roller, having its pivots moveable laterally to adjust the wire and keep it O parallel. I. is the pulp roller, or, ** dandy," to press out water, and to set the paper, r, is the place of the second, when it is used. H is the first or wet press, or couching rollers ; the wire leaves the paper here, which latter is couched upon the endless felt p; and the endless wire o returns, passing round the lower couch roller. By Mr. Donkin's happy inven- tion of placing these rollers obliquely, the water runs freely away, which it did not do when their axes were in a vertical line. e, e are the deckles, which form the edges of the sheet of I paper, and prevent the pulp passing away laterally. They regulate the width of the endless sheet. /,/are the revolving deckle straps. R is the deckle guide, or driving-pulley. ^ g, g are tube rollers, over which the wire passes, which da- mot partake of the shaking motion ; and. "WB-as 338 PAPER-MAKING MACHINE. PAPER-MAKING MACHINE. 339 A, h are moveable rollers for stretching the wire, or orass carriages for keeping t]l« rollers g, g m a proper position. ^ ^y^'s »-'■ c is the second press, or dry press, to expel the water in a cold state shfet""' *"*"*' *" ^* ""'^^ °^ '^^ ^''^^'' ""^' ^^ ^^^ '*^*^ cylinders for drying the endless t, i are rollers to convey the paper. JdZV^^'^o^-I^To^L^: ''''■• *""* — o»«PP«rt a., paper. „d prevent i. D, D are the hexagonal expanding reels for the steam-dried paper web, one onlv beins ised at a time, and made to suit different sizes of sheets. I is their swing fulc^Sm F, r, F, F, IS the frame of the machine. ^ luicrum. The deckle straps are worthy of particular notice in this beautiful machine Ther are composed of many layers of cotton tape, each one inch broad, and to?e*ther one half mch thick, cemented with caoutchouc, so as to be at once perfectly flexible and water-tight. «- / *v »iiu The upper end of each of the two carriages of the roller l is of a forked shape, and the pivots of the roller are made to turn in the cleft of the forked carriages in sih a manner, that the roller may be prevented from having any lateral motion, while it possesses a tree vibratory motion upwards and downwards ; the whole weight of the roller l beine borne by the endless web of woven wire. * The greatest difficulty formerly experienced in the paper manufacture upon the continuous system of Fourdnnier, was to remove the moisture from the pulp, and condense It with sufficient rapidity, so as to prevent its becoming what is caUed water-galled, and to permit the web to proceed directly to the dn ing cylinders. Hitherto no invention has answered so weJl m practice to remove this difficulty as the channelled and perforated pulp rollers or dandies of Mr. John Wilks, the ingenious partner of Mr. Donkin; for which a patent was obtained m 1830. Suppose one of these rollers (see l, in Jig 1038 and MM, in >g 1043) is required for a machine which is to make paper 54 inches wide. It must be about 60 inches long, so that its extremities (seeyig«.1039andlO4O)mav extend over or beyond each ^ge of the sheet of paper upon which it is laid. I^d ameter may be 7 inches. About 8 grooves, each l-16lh of an inch wide, are made in every inch of the tube ; and they are cut to half the thickness of the copper, with a rSn "ularly shaped tool. A succession of ribs and grooves are thus formed throughout the whole length of the tube. A similar succession is then made across the former, but of 24 in the inch and on the opposite surface of the metal, which by a peculiar mode of manage- ment had been prepared for that purpose. As the latter grooves are cut as deep asThc r?u> ^^^^^ ""V^^ "'''**^ ""^^^ ^^"^^ °" '^^ ^"tside, crossing each other at righ angles and thereby producing so many square holes; leaving a series of straight copper rib! on he interior surface of the said tube, traversed by another series of ribs coiled round them on the outside, forming a cylindrical sieve made of one piece of metal. The rough edges of all the ribs must be rounded off with a smooth file into a semi-circular form. Pig*. 1039, and 1040. a a, are por- tions of the ribbed copper tube. Fig, 1039 shows the exterior, and Jig. 1040 the in- terior surface ; 6, b and 6, b show the plain part at each of the ends, where it is made fast to the brass rings by rivets or screws ; c, c are the rings with arms, and a centre piece in each, for fixing the iron pivot or shaft B ; one such pivot is fixed by rivet- ing it in each of the centre pieces of the rings, as shown at c, Jig. 1040 ; so that both the said pieces shall be concentric with the rings, and have one common axis with each other, and with the roller. At a, a, a groove is turned in each of the pivots, for the purpose of suspending a weight by a hook, in order to increase the pressure up- on the paper, whenever it may be found necessary. Fig. 1041 is an end view, showing the copper tube and its internal ribs a, a ; the brass rings c, c ; arm d, d, d ; centre piece e, and pivot b. Fig. 1042 is a section of the said ring, with the arms, &c. The roller is shown at l. Jig. 1038, as lying upon the surface of the wire-web. The relative position of that perforated roller, and the little roUcr 6, over whid» it lies, is such that the axis of l is a little to one side of the axis of 6, and not in the same vertical plane, the latter being about an inch nearer the vat end. Hence, when- ever the wire-web is set in progressive motion, it wUl cause the roller l to revolve upon its surface ; and as the paper is progressively made, it will pass onwards with the web under the surface of the roller. Thus the pulpy layer of paper is condensed by compression under the ribbed roller; whUe it transmits its moisture through the perforations, it becomes sufficiently compact to endure the action of the wet press rollers h, h, and also acquires the appearance of parallel hues, as if made by hand m a 1 'J \A * Mn Wiis occasionally employs a second perforated roller in the same paper machine, which is then placed at the dotted lines »,*»»-. _,« ♦• r The patentee has described in the same specification a most ingenious modification of the said roller, by which he can exhaust the air from a hollowed portion of its periphery, and cause the paper in its passage over the roller to undergo the sucking operation of the partial void, so as to be remarkably condensed ; but he has not been called upon to apply this second invention, in consequence of the perfect success which he has experi- enced in the working of the first. The following is a more detailed illustration of Mr. Wilks' improved roller. Fie. 1043 represents two parts of his double-cased exhausting cylinder. * *^ This consists of two copper tubes, one nicely lining the other; thel inner being punched full of round holes, as at K, K, where that tube is shown un- covered; a portion of the inner sur- face of the same tube is shown at L, L. In this figure also, two portions of the outer tube are shown at m, m, and N, N ; the former being an external, and the latter an internal view. Here we see that the external tube is the ribbed perforated one already described ; the holes in the inner tube being made in rows to correspond with the grooves in the outer. The holes are so dis- tributed that every hole in one row shall be opposite to the middle of the space left between two holes in the next row, as will appear from inspection of the figure. The diameter of each of the punched holes somewhat exceeds the width of each rib in the inside of the outer cylinder, and every inside groove of this tube coincides with a row of holes in the former, which construction permits the free transudation or perco tetion of "the'' water out of the pulp. At each end of this double-case cylinder, a part is left at N, N, plain without, and grooved merely in the mside of the outer tube The smooth surface allows the brass ends to be securely fixed ; the outer edge of the brass rine fits tight into the inside of the end of the cylinders. j.v. 6u the inside of each of these rings there are four pieces which project towards the centre or axis of the cylinder; two of which pieces are shown at a, a. Jig, 104dm section. 6, 6, is a brass ring with four arms c, c, c, c, and a boss or centre piece d^ d. The outer edge of the last-mentioned ring is also turned cylindncal, and ot such » diameter as to fit the interior of the former ring o, o. The two rings are securely held together by four screws. «, c is the hollow iron axle or shaft upon which the cylinder revolves. Its outside is made truly cylindrical, so as to fit the circular holes in the bosses d, d, of the rings and arms at each end of the cybnder. Hence, U the hollow shaft be so fixed that it will not turn, the perforated cylinder is capable of having a rotatory motion given to it round that shaft. This motion is had recourse to, when the vacuum apparatus is employed. But otherwise the cylinder is made fast to the hollow axle by means of two screw clamps. To one end of the cylinder, as at p, a toothed wheel is attached, for communicating a rotatory motion to it, so that its surface motion shaU be the same as that of the paper web; otherwise a rubbing motion might ensue, which would wear and injure both. , _r r The paper stuff or pulp is allowed to flow from the vat A, fig. 1038 on to the surface of the endless wire-web, as this is moving along. The lines o, o, fig. 1088 show the course of 340 ■ f i ''l\ ^B i 1 »i PAPER-PULP STRAINER. the motion of the web, which operates as a sieve, separating to a certain de^ee the Wfttef from the pulp, yet leaving the latter in a wet state till it arrives at the first^pair of pres* ing rollers h, h, between which the web with its sheet of paper is squeezed. Thick paper, in passing through these rollers, was formerly often injured by becoming water galled, from the greater retention of water in certain places than in others. But Messrs. Donkin's cylinder, as above described, has facilitated vastly the discharge of the water, and enabled the manufacturer to turn off a perfectly uniform smooth paper. In Jig. 788, immediately below the perforated cylinder, there is a wooden water- trough. Along one side of the trough a copper pipe is laid, of the same length as the cylinder, and parallel to it; the distance between them being about one fourth of an inch. The side of the pipe facing the cylinder is perforated with a line of small holes, which transmit a great many jets of water against the surface of the cylinder, in order to wash it and keep it clean during the whole continuance of the process. The principle adopted by John Dickinson, Esq., of Nash Mill, for making paper, is different from that of Fourdrinier It consists in causing a polished hollow brass cylinder, perforated with holes or slits, and covered with wire cloth, to revolve oyer and just in contact with the prepared pulp : so that by connecting the cylinder with a vessel exhausted of its air, the film of pulp, which adheres to the cylinder during its rotation, becomes gently pressed, whereby the paper is supposed to be ren- dered drier, and of more uniform thickness, than upon the horizontal hand mOta^ds, or travelling wire cloth of Fourdrinier. When subjected merely to agitation, the water is sucked inwards through the cylindric cage, leaving the textile filaments so completely interwoven as, if felted among each other, that they will not separate without breaking, and, when dry, they will form a sheet of paper of a strength and quality relative to the nature and preparation of the pulp. The roll of paper thus formed upon the hollow cylinder is turned off continuously upon a second solid one covered with felt, upon which it is condensed by the pressure of a third revolving cylinder, and is thence delivered to the drying rollers. Such is the general plan of Mr. Dickinson's paper machines, into which he has intro- duced numerous improvements since its invention in 1809, many of them secured by patent right; whereby he has been enabled to make papers of first-rate quality, more par- ticularly for the printing-press. See infrii. In July, 1830, Mr. Ibotson of Poyle, paper manufacturer, obtained a patent, see b, Jig, 788, which has proved very successful, for a peculiar construction of a sieve or strainer. Instead of wire meshes, he uses a series of bars of gun-metal, laid in the bottom of a box, very closely together, so that the upper surfaces or the fiat sides may be in the same plane, the edge of each bar being parallel with its neighbor, leaving parallel slits between them of from about l-70th to 1-lOOth of an inch in width, according to the fineness or coarseness of the paper-stuff* to be strained. As this stuff is known to consist of an assemblage of very fine flexible fibres of hemp, flax, cotton, &,c., mixed with water, and as, even in the pulp of which the best paper is made, the length of the said fibres considerably exceeds the diameter of the meshes of which common strainers are formed, consequently the long- est and most useful fibres were formerly lost to the paper manufacturer. Mr. Ibotson's improved sieve is employed to strain the paper-stuff previously to its being used in the machine above described, (see its place at b in the vat.) When the strainer is at work, a quick vertical and lateral jogging motion is given to it. by machinery similar to the jig- ging screens of corn mills. Since the lateral shaking motion of the wire-web in the Fourdrinier machine, as origin- ally made, was injurious to the fabric of the paper, by bringing its fibies more closely together breadthwise than lengthwise, thus tending to produce long ribs, or thick streaks in its substance, Mr. Geoi^e Dickinson, of Buckland Mill, near Dover, proposed, in the specification of a patent obtained in February, 1828, to give a rapid up-and-down movement to the travelling web of pulp. He does not, however, define with much pre- cision any proper mechanism for effecting this purpose, but claims every plan which may answer this end. He proposes generally to mount the rollers, which conduct the horizontal endless web, upon a vibrating frame. The forepart of this frame is attached to the standards of the machine, by hinge joints, and the hinder part, or that upon which the pulp is first poured out, is supported by vertical rods, connected with a crank on a shaft below. Rapid rwtatory motion being given to this crank-shaft, the hinder part of the frame necessarily receives a quick up-and-down vibratory movement, which causes the water to be shaken out from the web of pulp, and thus sets the fibres of the paper with much greater equality than in the machines formerly constructed. A plan similar to this was long ago introduced into Mr. Donkin's machines, in which the vibrations were actuated in a much more mechanical way. John Dickinson, Esq., of Nash Mill, obtained a patent in October, 1830, for a method of uniting face to face two sheets of pulp by means of machinery, in order to prodace paper 1j PAPER-PULP STRAINER. U of extraordinary thickness. Two vats are to be supplied with paper stuff as «s"al ; « whSh two hSlow barrels or drums are made to revolve upon axles dnven by any fi«* moier; an endless felt is conducted by guide rollers, and brought »»^t« co°^ct^with ^ drams' the first drum gives off the sheet of paper pulp from its periphery to the lelt, whkh passing over a pressing roller, is conducted by the felt to that part of a second Irum whTcH in contact with another pressing roller. A similar sheet of paper pulp is now g^en off f om the second drum, and it is brought into contact with the fo'^er by the w^sure of its own roller. The two sheets of paper pulp thus united are earned forwarf byX felt overT guide roller, and onward to a pair of pressing rolers, where by contact the moUt surfaces of the pulp are made to adhere, and to constitute one double thick iLHf pape ,^^^^^^^ afte? passing over the surfaces of hollow drums heated by steam S;«™« Arl\ni\ romnact The rotatory movements of the two pulp-lifting drums must ^brul yt sTm^utSut buMhTof theVssing rollers should be a Uttle faster, b^use the sheets extend by the pressure, and they should be drawn forward as fast as they arc deliver^ otheiwise creases would be formed. Upon this invention is founded Mr Dick- S.iigSs method of making safety-paper for Post-office stamps, by mtroducmg '%^7X^ngl^^^nVo^^^^^ inventive manufacturer is a peculiaHy elegant mechLical arilngement, and is likely to conduce to the perfection of machine-made pa^r Thave akeady described Mr. Ibotson's excellent plan of parallel shts or gridiron strSners which has been found to form paper of superior quality, because it penmls all JheSared tenacious fibres to pass, which give strength to the paper, while it intercepts the coarS knots and lumps of he paste, that were apt to spoil its surface. Mr. Turn- S's c^irc^ar w?re sieves, presently to be noticed, may do good work, but they cannot com- SefewUh Mr Dickinson's present invention, which consists in causing the dUuted paper TufpTo pass i,etween longitudinal apertures, about the hundred-and-fifteenth part of an Mich wide, upon the surface of a revolving cylinder. v •„ „ ^«i;^„„^ The pulp being diluted to a consistency suitable for the paper machine, is de ivered into a vat, of which the level is regulated by a waste pipe, so as to keep it nearly full. From this vat there is no other outlet for the pulp, except through the wire-work pen- nhm of the revolving cylinder, and thence out of each of its ends mto troughs placed alongside, from which it U conducted to the machine destined to convert it into a ^ThcTevolving cvlinder is constructed somewhat like a squinel cage, of circular rods, or an endless spiral wire, strengthened by transverse metallic bars, and so formed that the spaces between the rings are suflicient to allow the slender fibres of the pulp to pass throueh, but are narrow enough to intercept the knots and other coarse impurities, which must of course remain, and accumulate in the vat. The spaces between the wires of the squirrel cage may vary from the interval above stated, which is mtended for the finest paper, to double the distance for the coarser kinds. , , . v v • It has been stated that the pulp enters the revolving cylinders solely through the inter- val^ of the wires in the circumference of the cylinder; these wires or rods are about three ei'^hths of an inch broad without, and two eighths within, so that the circular slits diverge ^internally. The rods are one quarter of an inch thick, and axe riveted to the transverse bars in each quadrant of their revolution, as well as at their ends to the necks of the cylinder. ^ j .v .v Durin*' the rotation of the cylinder, its interstices would soon get clogged with the pulp were not a contrivance introduced for creating a continual vertical agitation in the inside of the cylinder. This is effected by the up-and-down motion of an interior agitator or plunger, nearly long enough to reach from the one end of the cylinder to the other, made of stout copper, and hollow, but water-tight. A metal bar passes through it, to whose projecting arm at each end a strong link is fixed ; by these two links it is hung to two levers, in such a way that when the levers move up and down, they raise and depress the a<'itator, but they can never make it strike the sides of the cylinder. Being heavier than Its own bulk of water, the agitator, after being lifted by the levers, sinks suddenly afterwards by its weight alone. ... _, The agitator's range of up-and-down movement should be about one inch and a quarter, and the number of its vibrations about 80 or 100 per minute ; the flow of the pulp through the apertures is suddenly checked in its descent and promoted in its ascent, with the effect of counteracting obstructions between the ribs of the cylinder. The sieve cylinder has a toothed wheel fixed upon the tubular part of one of its ends, which works between two metal flanches made fast to the wooden side of the vat, for the purpose of keepins the pulp away from the wheel ; and it is made to revolve by a pinion fixed on a spindle, which going across the vat, is secured by two plummer blocks on the outside of the troughs, and has a rotatory motion given to it by an outside rigger or pulley, by means of a strap from the driving shaft, at the rate of 40 or 50 revolatio!it 342 PAPEB-PULP STRAINER. rer minute. This spindle has also two double eccentrics fixed upon it, immediately under the levers, so that in every revolution it lifts those levers twice, and at the same **"The dlametw^* *the sieve cylinder is not very material, but 14 inches have been found a convenient size ; its length must be regulated according to the magnitude of the machine which it is destined to supply with pulp. One, four feet long in the cage part, is sufficient to supply a machine of the largest size in ordinary use, viz , one capable of making paper 4 feet 6 inches wide. When the cyUnder is of this length, it should have a wheel and ^"ue^l flanchTs ire firmly fixed to the sides of the vat, with a water-tight joint, and form the bearings in which the cylinder works. Mr. Turner of Berraondsey, paper-maker, obtained a patent m March, 1831, lor a peculiar strainer, designed to arrest the lumps mixed with the finer paper pulp, thereby he can dispense with the usual vat and hog in which the pulp is agitated mimedialely before it is floated upon the endless wiie-web of the Fourdrinier apparatus. His strainer may also be applied advantageously to hand paper machines. He constructs his sieves of a circular form, by combining any desirable number of concentric rings of metal, with small openings between them, from the 50th to the lOOlh part of an inch wide. In order to facilitate the passage of the fine pulp and water, the sieves receive a vibratory motion up and down, which supersedes the hog employed m other paper making "° A mechanism to serve the same purpose as the preceding, in which Mr. Ibotson»s plan of a parallel rod-strainer is modified, was made the subject of a patent by Mr. Henry Brewer, of Surrey Place, Southwark, in March, 1832. He constructs square boxes with gridiron bottoms, and gives a powerful up-and-down vibration in the pulp tub, by levers, rotatory shafts, and cranks. r i t l n j v ♦i.:- As the contrivance is not deficient in ingenuity, and maybe useful, I shall describe thw mode of adapting his improved strainers to a vat in which paper is to be made by hand moulds. A hog (or churning rotator) is employed for the purpose of agitating the pulp at the bottom of the vat, in which the sieve is suspended from a crank-shaft, or in any other way, so as to receive the up-and-down vibratory motion for the purpose of straining the pulp. The pulp may be supplied from a chest, and passed through a cock into a trough, by which it is conveyed to the strainers. ,.,.,. , . A pipe from the bottom of the vat leads into a lifter-box, which is designed to convey thin pulp into the sieve, in order to dilute that which is delivered from the chest. This pipe also allows the small lumps, called rolls, to be re-sifted. The pressure of the pulp and water in the vat forces the pulp up the pipe into the lifter-box, whence it is taken by rotatory lifters, and discharged into a trough, where it runs down and mixes with the thick pulp from the chest, as before mentioned. By these means the contents of the vat are completely strained or sifted over again in the course of almost every **A patent was obtained for a paper-pulp strainer by Mr. Joseph Amies, of Loose, in the county of Kent, paper manufacturer, who makes the bottoms of his improved strainers veith plates of brass or other suitable metal, and forms the apertures for the fine fibres of pulp to pass through, by cutting short slits through such plates, taking care that as much metal is left between the ends of each short slit and the next following as will properly brace or stiffen the ribs of the strainer ; and he prefers that the end of one slit shall be nearly opposite to the middle of the two slits next adjoining it, which is commonly called blocking the joints. This is for giving rigidity to the bottom of the strainer, and constitutes the main feature of his improvement. The bottoms of sieves previously constructed with long metallic rods, he considers to be liable to lateial vibra- tion in use, and thus to have permitted knots and lumps to pass through their expanded intervals. This objection is not applicable to Mr. Dickinson's squirrel-cage strainer, of which the ribs may be made rigid by a sufficient number of transverse bars ; nor in fact is it applicable to Mr. Ibotson's original strainer, as it is admirably constructed by Messrs. Donkin and Co. Each bar which they make being inflexible by a feathered rib, is render- ed perfectly straight in its edge by grinding with emeiy upon a flat disc-wheel of block tm, and of invariable length, by a most ingenious method of turning each set of bars in a lathe The bars are afterwards adjusted in the metallic sieve-frame, or chest, at any desired distance apart, from the 120th to the 60th of an inch, in such a manner as secures them from all risk of derangement by the vibratory or jogging motion m shaking the pulpy fibres through the lineal intervals between them. , Mr. James Brown, paper manufacturer, of Esk mills, near Edinburgh, obtained a patent in May, 1836, for a particular mode of applying suction to the pasty web in the Fourdrinier's machine. He places a rectangular box transversely beneath the hori- Kmtal wire cloth, without the interposition of any perforated covering, such as had been PAPER CYLINDER MACHINE. 343 tried in the previously constructed vacuum machines, and which he considers to have S^ed'ed l^ei?Xacy'in condensing the pulp and extracting the water. merous small perforations t^* the paper j^ continuous paper machine was A modification of Mr. Dickinson s cy»™J« . ^ Dartford, as „ade the -^i«" "^ » J»7 „;:iJ^„e7Sf ab^ad' Th"^^^^^ f-"" "'..l!" eonununicated to him »? » "f''"*;,! i„ „hich the wire cylinder is immersed with • invention is a mode »f ?"PP'j'"j,^' ™f ereaUng a considerable pressure upon the exter- r:u"rrat7 Wntr%7dT^f causin,\h^ fibres of the paper pulp to «ihere t. %rre"is a -i-cyUndric^ t^ugh in whi^h Jbe m^^^ revolve by any '""^ll^"' ■""^"*;/.te Cm!n»"ld opposite to the vat, thee is a cis- at its bottom paru 9n the side »f '7.fjX«ed;whdeh passes thence into the semi- tern into which a copious How of "»'"■'/«"' "."^^^^^^ L « bent or syphon tube is cylindrical trough. In the ■"'"'"'^ "J *'^^f.*'\„J^ j.-X the ™^^ reVolves. ThU introduced, on the horizonta part of ™''''='? «"'^' '"'^'wa^rTdrawn from the in- tube is connected at the outs^e ^;;^'X''V^[J^f,,*:eri;iindSrtrough, on the ter or of the cylindrical mould. Thus .y>« "?'" j" , . ,v' ;, jg within; arvd con- outside of the drum, is kept at a «»»5'^«""> Jf ""^ '^.1' w?re gauze, will, it it sup- scuentiy '^e pressure of the water as it P^-«,* »»f,,f,i7-„S:e of the moulS: In order to keep the pulp properly agitated in the mould vat j^ a se^^eni ^ ^^5 Ara. cuuin mi r> communicaton from a foreigner residing abroad. tlTTl^^r^CZl pr lU anln^L^^'^^^^^^^^ which they are agit^ed tj rrpLmVelhe dust •nfe Seaned fragments are delivered o^ ^o a horizontal screen or ^nS^a table to suffer examination. When picked here, they are ready for the pulp- ^^. A dSinct repTesLation of this machine is given in Newton's Journal, con- *'Mr Jetn 'jltuI;'jeq^ui^r^L^^^ a patent in August, 1831, for a mode of making naSer' on the conUn„7us machine with wire-marks. The proposed improvement Ets merely in the introduction of a felted pressing roller, to act upon the paper afl« U has beTn diJcharged fr >m the mould, and need not therefore JL« P;^2rv J^the co^ In August, 1830, Mr. Thomas Barratt, paper-maker, of St. Maiy Cray, in the county of Kent obtained I patent for an apparatus by which paper may be manufactured ma ^nSous hUtrwi^h the water-mark and maker's name, so as to^e^en^^l^^jl/;^ respect paper made by hand, in moulds the size of each separate sheet. On the vme web at equal distance J apart repetitions of the maker's name or other device is i^ace^ recording to the size of the 'paper when cut up into sing e «»^««ts- J« °^^"/*^*^'^"^ such paper, the ordinary method of winding upon a reel cannot be employed ; a^ therefore the patentee has contrived a compensating reel, whose diameter diminishes a^ «Iich revolution, equal to the thickness of a sheet of paper. See Newton's Journal, C. S. ""^F Jr" Mr.^Lemuel Wellman Wright's series of improvements in the manufacture of paper, spedfied in his patent of November, 1834, 1 must refer to the above Journal, ^ A commiltee ?f the SociitS d' Encouragement, of Paris, made researches upon the best composition for sizing paper in the vat, and gave the foUowmg recipe :— 60 344 PAPER, SIZING OF. 100 kilogrammes of dry paper stuff. 12 — starch. 1 — rosin, previously dissolved in 500 gnunmet ,o ., - of carbonate of soda. 18 pails of water. M. Braconnot proposed the foUowing formula in the 23d volume of thp JhtrurU. ^m Chxmteet de Physique :-To 100 parts of dry stuff, properly dXsedthrou^ItJ? add a boilm? uniform solution of 8 parts of flour with ftTrnLh .• *"^°"?'i ^»^er, «„der .he li,uor clear. AM U,lZ^ZiT^u!^''s^,"'^^.^^^aisZ7^t^, e Jof tlnP^«n7d ' P""*'' si^e them previously with the following composition :-4 oun- Te Sh^^nn • 7?^ ""^ "^^^^ '*^^P ^^«^«'^^ '^ 3 English pints of horwatei When inm^J^r- •' ^?Pi^^^' t^« o"«ces of pounded alum must be added, andls si>n as th« VaZenC^t m^liVfor^iztr;^^^^^^^^^ t'"''"^'''''' ^^^^^'' ^^ ^^^'^^^ ^^ 100 kilogrammes of dry stuff. J — glue. 8 — resinous soap, " — alum. uniform , the ?lue, prev[ottX MftM;H hv I9 h ' "" '^' "?'""'' ''*<='"»" I""* •826, p. 226, but they ISlrdlfprLserv^^^^^^ iree has been acclimated in France ^""««a'"e '» « European manufacturer. Thai smooth tables, in order to d^ it flat ?^^^ ^'^^^ ^'^ ^> ^"^^^-^' "P«^ feet long, and two broad It i, mLp nf ikI k ^"P^°y^ 'P^ engravings is in sheets four too strong for tMs purpose. ' ^*™'^ ' '^^"^ myrtle-tree paper would be Paper, sizing of. Mr John Dickinson obtained a patent, in 1840 for a mo^. nf • Tu V * ii 7Vac«7il -' 1 346 PAPER. Thomas Barrett claims, in his patent of 1841, « a mode of drying paper by applying streams of air to its two surfaces, as it passes over the steam cylinders, whether in the state of engme size or water leaf, or after sizing ; as also, the application of currents of air to the surfaces of paper, after sizing, in order to cool the size ; as the paper is pass- ing to the drying cylinders." ^!f,**®^""P™^^°^«^^ "* paper-making, for which T. W. Wrigley, of Bridge Hall Mills, Bury, obtained a patent In 1842, relate to the rag engine. Jigs. 1045,1046,1047, 1048. JFtg'. 1045is a side elevation ; ^g. 1046, a transverse section, taken lengthwise through nearly its middle; y!g. 1047 a plan view of the apparatus detached upon a 1048 1047 larger scale; and j^g.l048is an elevation. T^e vessel in which the rags are placed is shown at a a, and in about the centre of this vessel the beating or triturating roll, b, 6, is placed : it is surrounded with the blades or roll bars, c c, fig. 1046. The roll is mounted upon a shaft, d d, one end of which is placed in a pedestal or bearing on the further side of the chamber a, and the other in a bearing upon the arm or level e «•, fig. 1045 which is supported by its fulcrum, at the end e*, in one of the standards,/ /, and at the other end by a pin fixed in the connecting rod, g g. At the upper end of this connecting rod there is a cross-piece, or head A, having turned pivots at each end upon which are placed small rollers, i t, resting upon a horizontal cam, k fe, which is made to revolve. This cam, k fc, by means of its gearing, causes the roll 6 first of all to wash the rags a short time, then to be lowered at whatever rate is desired for break- ing the fibres; to be maintained at the lowest point for the required number of revolu- tions for beating ; and to be raised and retained, as required, for the final purpose of PAPER. 341 clearing the pulp. The upper or working edge of this cam is to be shaped exactly according to the action required by the engine roll; as, for instance, suppose the previous operation of washing to be completed, and the time required for the operation of the rag machine to be three hours, one of which is required for lowering the roll, that, or the first division of the working surface of the cam, k k, must be so sloped or inclined, that, according to the speed at which it is driven, the rollers upon the cross- head shall be exactly that portion of the time descending the incline upon the cam, and consequently lowering the roll upon the plates Vyfig. ill ; and if the second hour shall be required for the roll to beat up the rags, the roll revolving all the time in contact with the plates, the second division of the cam, k fc, must be so shaped (that is, made level), that the roll shall be allowed to remain, during that period, at its lowest point; and if the third portion of the time, or an hour, be required for raising the roll again, either gradually or interruptedly, then the third division of the cam, k, must be suitably shaped or inclined, so as to cause the cross-head to lift the roll during such interval or space of time ; the particular shape of the inclined portions of the cam de- pending on the manner in which the manufacturer may wish the roll to approach to or recede from the bottom plates, during its descent and ascent respectively. Its mode of connexion and operation in the rag engine is as follows : supposing that the rags intended to be beaten up are placed in the vessel a, fig. HI, and motion is communicated, from a steam-engine or other power, to the farther end of the shaft d, the roll 6, will thus be caused to revolve, and the rags washed, broken, and beaten up, as they proceed from the front weir m, over the bottom plates n, and again round by the back weir o. There is a small pulley p, upon the near end of the shaft rf, round which a band q passes, and also rouno another pulley r, upon the cross shaft s ; upoa this shaft is a worm /, gearing into a worm-wheel «, fixed upon another shaft r, below ; upon the reverse end of which is a pinion ty, gearing into a spur-wheel a:, upon the end of a shaft y ; and upon the centre of this shaft y, there is another worm z, gearing into a horizontal worm-wheel 1, upon which the cam, k k, is fixed. Thus it will be seen, that the requisite slow motion is communicated to the cam, which may be made to perform half a revolution in three hours ; or it will be ev lent, that half a revolution of the cam, fcfe, maybe performed in any other time, according to the calculation of the gearina: employed. The shaft may also be driven by hand, so as to give the required motion to the cam. Supposing, now, at the beginning of the operation, the cross head bearing the lever and roll, to be at the highest point upon the cam, k fc, as its revolu- tion commences, the roll will revolve for a short time on the level surface of the cam. and will then be lowered until the cam, k fe, has arrived at that point which governs the time that the roll remains at the lowest point, for the purpose of beating the rags into palp, and as the cam,/cAr, continues to revolve, and thus brings the opposite slope upoa the third portion of its working surfiace into action upon the cross head, the roll will be raised, in order to clear the pulp from knots and other imperfections, and thus complete the operation of the engine. In order to raise the cross head and roll to the height from which it descended without loss of time, or to lift the cross head entirel}' from off the cam when requisite, a lever, 2, or other suitable contrivance may be attached to the apparatus, also a shaft may be passed across the rag-engine, and both ends of the roll may be raised instead of one only, as above described. 'the patentee does not claim as his invention the lowering and raising the roll of the rag-engine, nor the lowering of it by mechanism, as this was effected in Mr. Amos's patent of 1840 ; but he claims the above peculiar apparatus for this purpose. Heio- ion^s Journal, xxiii. 254. C. S. Quantity of Paper charged with Duties of Excise, in the United Kingdom, in 1834. 1835. 1836. First Class - - - - - Second Class .... Pasteboard, millboard, doubleT coi kcr^ ^^ '^' ^ ^ ^^^ manufacture appears to be still rapidly on the I^eclared Value of Stationery and Printed Books exported in Years. 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 Stationery. £ 195,110 208,532 190,652 171,848 179,216 177,718 211,518 211,459 259,105 301,121 Printed B)»oks. £ 107,199 102,874 109,878 95,874 101,110 93,038 124,635 122,695 148,318 178,945 Total. £ 802,309 811,406 800,630 267,722 280,326 270,766 886,063 834,064 407,423 480,063 Till the paper trade shall escape entirely from the clutches of its ancient dry-nurse, the excise, neither it nor the book trade can acquire the same ascendency in exportati^ which all other articles of British manufactures have over the French. The Value of Stationery exported in France, from 1833, was, 18,992 francs Cartons lustres (polished pasteboards for the cloth manufacture) Cartons en feuilles (pasteboard in sheets) - - - Cartons monies (papier-mache) - _ . . Cartons coupes et assembles - - - . . Wrapping paper --.-.. White paper, and ray6 (ruled) pour musique - - . Coloured paper in reams - - - - . Stained paper (paper hangings) in rouleaux - - . Silk paper -----.. 6,352 215,376 64,184 178,644 2,903,075 68,541 1,885,387 3,240 Total (—£208,000) 6,323,621 francs Mr. John Dickinson's invention for sizing paper, continuously, in an air-tight vessel (partially exhausted of air,) by unwinding a scroll of dried paper from a reel, and qoZ W,m.\mWM<,m^^^^ll^iaiy^y^Yf^^pm ducting it through heated size ; then, after pressing out the superfluous size, winding the paper on to another reel A longitudinal section of the apparatus employed for this purpose, is represented in ^. 1049. a, is the air-tight vessel; 6, the reel upon which the paper to be sized is wound, from whence it proceeds beneath the guide-roller c, and through the heated size, to another guide-roller d; it then ascends between the press-rolls e,f, (bv the revo- lution of which the paper is drawn from the reel 6 (and is wound upon the reel g), A float A, is suspended from the cross-bar i, of the vessel a, for the purpose of diminish- ing the surface of size exposed to evaporation ; and beneath the bottom of the vessel is an enclosed space y, into which steam or hot water is introduced, for raising the tem- perature of the size. Water-marks. — In the manufacture of all hand-made papers, for the purpose of writing or printing upon, and of much machine-made paper, for the like purposes, it is the practice to form therein a device, name, and date, or some of them, known as the water-mark. These marks are produced by attaching to the surface of the mould or dandy roller, employed in the manufacture of paper (usually by sewing with fine wire)^ cylindrical and sometimes flattened wire, previously formed into the designs or marks intended to be produced in the paper; which designs or marks, thus attached to and lying above the general surface of the mould, occupy a space thereon, which, if they had been absent, would have been charged with pulp, and thereby cause the sheet of paper in progress of manufacture to be thinner at the particular parts of the mould where the marks or designs are attached, by the thickness of the wire used in the same marks or designs ; and the same apparent effect is indeed produced upon the sheet of paper in progress of manufacture as is produced by an ordinary die on any substance It may be caused to act upon, — with this difference, however, that on the sheet of paper the impression is the sunken one. It is obvious, from the use of cylindrical wire, or flattened wire, having its sides parallel with each other, that the mark ultimately produced will be formed of a number of lines of equal breadth ; unless, indeed, in the same figure, wires of different gauges, thicknesses, or breadths, be employed ; and even in the latter case (which, indeed, in practice, it is believed seldom occurs), the transition from the different gauges would be abrupt and ill adapted to the proposed end. Also in forming designs of intricacy with wire, a frequent crossing of it is necessary ; by which means, at the points of crossing, the mark will necessarily be the thickness of two wires, and, consequently, the water- mark on the sheet of paper will be stronger at those points ; or, if to avoid the crossing the wire be cut, so that an end might abut against the length of the wire in an intricate design, the pieces of wire would be so short and so numerous as to render the sewing or fastening of them to the mould exceedingly difficult and of great expense, and, in some cases, wholly impracticable. With respect to the imitation of hand-writing, or the introduction of fac-simile autographs as water-marks, it is scarcely necessary to observe, that the observations before made, in relation to general designs, will apply with greater force to them ; and that, at the best, they would be very imperfect, and in many cases, could not be effected at alL The remarks made, with reference to the water-marking upon moulds, is equally applicable to dandy-rollers. The object of this invention is to remedy the defects before pointed out, and to pro- duce a simple mark, or one of the highest ornamental character or intricacy ; the hues of which may vary from a thin line or faint shade to one of a greater depth of tone or breadth ; or, on the contrary, from a depth of shade to a fainter one ; and also to afford facility for introducing water-marks of the greatest intricacy, without the inconvenience or expense, before alluded to, of crossing the wire, and thus rendering some parts thicker than the main body of the mark, or cutting the wire into innumerable small pieces. These effects are attained bv the following means, whereby also the patentee is en- abled to produce fac-similes of ordinary hand-writing and of autograph signatures:— A plate of brass, copper, or other metal, being provided, of the requisite substance to Sroduce the depth of water-mark impression in the pulp (which substance must be etermined according to the required weight or thickness of the paper) — to one side of this plate is to be attached, by glue or other suitable means, a piece of card-board or Tcneer of wood, for the purpose of giving it rigidity and support ; and the design to be produced in the pulp as a water mark, having been drawn on paper, is then to be affixed, by glue or other suitable means, to the other surface of the plate. If the sheets of paper to be manufactured are not required to be very heavy, the plate may be thin ; and two thin plates of metal may be attached together, and be operated upon at one time. In this case, the paper, with the draught of the design, may be affixed to the outer surface of one of a pair of plates, previously attached together by glue, or other matter, having a piece of card-board or veneer of wood between them, for the purpose of keeping the two thicknesses of metal in contact, and for giving them rigidity. The i 'I 19 I: \ H 350 PAPER. plate, supported as stated, or the pair of plates, connected as described, is or are f7i«. to be pierced or perforated round the outlines of the device bvTliw«.l«^LY? *? purpose (after the method of cutting buhl workl aecordwX f k ' ?. ^ ^ ^a •*** drawn as before mentioned. The plat? or X^es havW h.in^ -^ Vf^^rxy or design cut to the figure of the device, thosfportion^ o? the m perforated, or or watermark are then to be disengaged Cm the p^rt^ of the li-^^''''" "^ '^^'"^ quired: which having been done, the drawn paper Wee card C!^ ^ ' "^^ ""^ be removed ; and if two plates of metal h^ve been cu?^f Anf^ ."^ or veneer, must separated from each othe? : this seTaration'L well a^^^ *^*>' ^'^ *« ^^ device, card-board, or veneer, can be efFected^^soakfng L ho " orl^^'" Ht' "^^S^:^^:^ o^rdLr/methoVof ':^^.^^:^^^^^^^^ In cases where a high finish to the water-mark or design is reauired or Ha-J^oKU +u edges, and such other parts of the metal as may be deSred shm M h! nK f 5 *t* rounded, or cut down."^ In order to do this, the ^letal Ss or parte of t'^^^^^^ ' plates are to be affixed, by some sufficient means, to a rigid b ockC hoM theif whiW operating upon: the metfiod which the patentee has adopted Tto^ln^tl,.. l1 device to a flat slab of marble, somewhat larger than th^dev ice fid th^s aSm??,' n/ Its being readily removed by soaking in hot water, after the operation next de^^^^^^ has been performed. The pattern or metal device being thusTffixe.nCfn,. f ^^ thereof is then to be dresse/ by cutting or filing at the p^arts where If r^.t K^^ '"'^*^^ to improve the effect of the pattern ; Ld the^edges wS hive b^^^^^^^^ shXrt^e saw can be removed or rounded by the scorper Sr engraver's tooTand thl^f^^i!^ off by stoning or other suitable means. The^bove m^tho^of fini^i tt^±^^^^^ designs applies only where the device is to be sewn on to the mHd o^r d«X 1i ^ith wire; but when solder is used, the metal device mav-afte^h«vinl dandy-roUer Tlie patentee, Mr. R. O. Bancks, claims as his improvement or imT.r«,r^rv, * • *u Messrs. Amos and Clare have obtained a patent for employing in r^lan^ «f *i,. couch roll (for working against the upper surface ofTheTaperY a ^ollfw^r^^^ T^i Of, ^ts surface, haying a sectiS box within it, actKL W "„ « ^^^^^^^ wherebj the deposition of colouring matter is rendered equal Sn both "ides ?fTh^ paper, instead of being greater on the lower side, by the natural sXidence «f f^! colouring matter from the water. They have also specified an improved kronfrn! a:rr;nt rr."^^^ ^^^^^ '^-^^"^ ^^ ''- ordinarTpTpr^lht^f.:: Th^th^^f i;ULP-METER Patented by Charles Cowan. Valley-field, near Edinburgh, ^e object of this apparatus is to measure out a uniform and exact supply^ pu"?/^ I l^^^K^f ^'^!?? according to any width and thickness of the web of paper^whicS ^ may be desired to make. The pulp, after having been prepared in the engiW and ^^ff oh /'tJ;*^'''"^ proportions of raw materials and water, is kept L ife pulp or BtuflF chest The cup of the pulp-meter which is driven in connection with the mper W Jnfl '%"^t ^? ^^P i^*^ \ ^^^ ^^^^^ H "^^*°« of * ball-cock or vX is always kept full of pulp from the pulp-chest and life, and delivers the requisite ouanJtTof pulp to make the width and thickness of the web required. This iVdone b\ m" ans of the slide upon the cup, which can be set even while the apparatus is in motion so as to dehver the number of cubical inches of pulp at each dip reauired for fhl !^' !?• i paper to be made, which can be ascertained by a very ZpKLl boSnfw^t^^^ as to their mtellectual reqf emente. is Le the annuaTSc'ease o wh7ch is'oi^LTs'e with the diffusion of knowledge. And it mavhp fri,W =o;^ Tu * ^"^^" ^ coextensive tually considered, thepresentllassrelft^^sr^ Ts LTnsXfvMer B^^^^^^^^ > h'' economy than any of those ini whUT exhfbZn nas been subdivided. Books, it has been said, carry the productions of the human mind PAPER AND PRINTING. 351 oyer the whole world, and may be truly called the raw materials of eyery kind of •cience and art and of all social improvement. The sub-classes are as follows:— A paper, m the raw state as it leaves the mill, such as brown paper, millboards, printing writing, and drawing papei-s, «*J^;^J° ^^^f P*^^"^^^ being greater than that of the surfaces of the paper to each f \«^- ^^^ 'P'^X^^^^^^ niay^tSn be removed bv damping, and so loosening the P^^^^^^f^^^f^Vv ^^^^^L^^^^^^^^^ paper. A bank-note, although of extremely thm texture can in JJ^^J^yj^fj^/^P^X^ Into two halves, on one of which remains the impression ot the plate, while tne oiner ^ liTh^ interesting collection of paper in the Exhibition from various paper mill^ there are Sih^^^^^^^^ niust be estimated by very different stendards • iTfor ilance, the brown wrapping and the fine hand-made drawing papery the suear and the fine printing papers, the bibulous plate-paper for engravers use and S: 3sS:d writing pV 'colLtively, it exW^^^^ which are soucht for by English consumers, and which in many respects ou^f "«™ ^ose required by our Continental neighbours; as an example may l>e ^^^^ed the 8ubstant?aTCS writmg-papers and the thin post papers of France and Belgium, whie different qualW^^^ the difference of postal regulations in those countries^ ^e system ofproducing paper in continuous lengths of machinery was first intro- duced by mSs^ FourdrinTe? into this country, they having purchased the Patent ri^ht of Mr GambWho in 1804, obtained permission from the French government to bring L' EngW a 1^^^^^^^ of a michine inve^nted in 1799 by ^ojs Robert who ^^^^^^^^^^ Xuity of Mr. Bryan Donkin: upon this 'has been founded the various descriptions of^naDe^maknnff machines which have since that time been introduced. They consist ^L^nt^^lWof ^^^^^^^ by which the paper pulp is. made to A^T - f .^7;^^^^^ arendless wire web • a rapid up and down motion being given to it for the Purpose of shakwThe watei' out of the pulp, and thus producing a comp ete interweaving of ItSfiLents. 'tL contin^uoS'sroU of P^r thus formed is turned o^^^^^^ second solid cylinder covered with felt, upon which it is condensed by « third, and fivpntuallv delivered to drying rollers. — Exhibition, Kewfrl Oj- , , -^^^^u,. Swedkh filterinTpaperls made with pure water, and is more free from impurity thaiTanrotherrt^^^ in fact, pure cellulose, and yields only half a per cent, of asli '"''^Tl^vZ^r. those with a ribbed surface; wove papers those -tb a tiniform surface.^ Ce papers under the microscope.no longer appear of uniform tmt ; on the contrary, the particles of colour are seen widely separated. materials, yet, commercially, the attempts have been "f ^<'«/«^™V , Prm>rietor^ 76. D^a Rue, Thomas, & Co., ^0 5^n/t^/ iJotj, J(ant./ac<^^^^^ ^^ffoU^- Envelope-folding machine invented by Edwin Hill and barren De la ^."^'Y/be toUow ^rfsthe action of this machine :— The feeding-boy places the previously e^t blank enve opTs on to a small platform, which rises and falls in tbe rectangular recess fomed bTthe^yhndrical axes of the folders, the bearings of the folders serving by ^^^J^^^' g^t on toVide the envelope into its place at the moment of tbe smaU platfonn f^in^ A plunger now descends and creases the envelope by carrying it between the foWer- axes, at the same time turning the flaps upwards m a vertical direction. The plungers wUch descends as a whole, now divides iito two parts, the ends rismg and the Bide* remaining down to hold the envelope until the end-folders have operated ; these latter turn oyer the flaps, the one on the right of the feeding-lad taking a slight precedence^ and being closely followed by the gumming apparatus, which takes gum from an endless blanket working in a trough, and, after applying it to the two end flaps, retires, at the same time the remaining half of the plunger moves upwards, to allow of the side folders turning over the remaining two flaps, and the folder nearest the feeder taking precedence. During these operations, the end folders have remained at rest, and the whole four open simultaneously. The taking-off" apparatus with its fingers tipped with vulcanized caoutchouc, now moves forward over the folded envelope, which is lifted upwards by the rise of the small platform and retreats with it, placing each envelope, as it is suc- cessively folded, under those which have preceded it. The envelopes are now knocked over on to an endless blanket, and are conducted by it between two cylinders for a final squeeze, and then rise in a pile up the trough. There is a provision m the machine by which the gummer is prevented placing gum upon the platform, in case the feeder omita feeding in an envelope. This machine works at the rate of 2,700 envelopes per hour, and although superseding hand-labour in folding, it is satisfactory to find that^ instead of displacing hands, its introduction, by extending the consumption, has in reality created work for more than it has displaced. Although the fashion of using envelopes was common in France, and had been, to a small extent, introduced into England prior to 1839, yet their consumption was too insignificant to call forth any but the rudest mechanical appliances. It is to the stimulus created by the adoption, in 1839, of Mr. Rowland Hill's system of postage reform, and the consequent increased demand for envelopes, that their manufacture owes its rank among the arts, and its possession of some of the most ingenious ma- chinery recently invented. The total annual number of letters passing through the Post Office in the United Kingdom before the change in the postage was about 76,000,000. The fourpenny rate and the alteration in the system of charge by number of enclosures to that by weight, was introduced on the 5th of December, 1839, and on the 10th of January, 1840, the rate was reduced to one penny; during that year the number of letters in- creased to 1 69,000,000, about half of which were enclosed in envelopes. The number of letters has been steadily increasing since that period, and during the year 1850, it reached the astonishing number of 347,000,000, or 1,000,000 per day; the proportion of letters enclosed in envelopes has likewise increased from one-half to five-sixths of the total quantity, so that in round numbers 300,000,000 of envelopes paes annually through the PostrOffice ; besides which there is nearly an equal number used in private con- veyance. What does this million of envelopes contain? Their exposition would furnish an instructive and entertaining study. In illustration of the articles sometimes sent by post, it may be cited, that some yean back, Professor Henslow was in the habit of receiving from members of an agricultural society which he had established, specimens of living slugs of various kinds, sent for examination, with a view to his advice for their extermination. Were it not for the cheap postage, many of the publishing societies now in existence would not have been established, on account of the expense of collecting manuscripts, transmitting proofe, and circulating books. But it is not only in this way that the postal reform hac extended its benefits, for with the reduction of rates, a liberal policy has increased the facilities of delivery by the establishment since 1839 of 4,600 new post oflSces, which are estimated as serving about 14,000 villages. 154. Specimens of Books and Tracts of the Religious Tract Society, instituted 1799. Depositories. 56. Paternoster Row, 65. St. Paul's Churchyard, and 164. Piccadilly. Treasurer, John Gurney Hoare. Esq. : Honorary Secretaries, Rev. W. W. Champneya^ M.A., and Rev. Ebenezer Henderson, D.D. ; Corresponding Secretary, Mr. Jones. The Society was formed to promote the circulation of religious books and treatises in foreign countries, as well as throughout the British dominions. It constitutes a Christian union of members of the Established Church and of Protestant dissenters. It has printed important tracts and books in about 100 languages ; its annual circulation from the depository in London, and from various foreign auxiliaries, amounts to about 24,000,000; its receipts for sales and benevolent objects, to more than 62,000/. ; and its total distribution to March, 1851, including the issues of its aflSliated societies, to about 649,000,000 copies of its publications. There are now about 4,743 English publi- cations, besides several hundred in foreign languages, on its catalogue. These worka are varied in size and contents, and suited to different classes of the community. Several books and tracts specially designed to improve and commemorate the Great Exhibition have been issued in English, French, German and Italian. By a carefully arranged system in the concerns of the depository, the sale of the publications is maie to cover all the expenses of producing them, and of the necessary establishment of the Society^ Vol. IL 2 Z 354 PAPER AND PRINTINa. f ' ^ I Thus, the whole of the subscriptions, donations and contributions is applied to the gratuitous circulation of its publications, without any deduction or charge whatever. In aid of home and foreign benevolent objects the Society receives about 6,560/., per annum, while its grants during the past year were 8,560/., being 2,000/. beyond the receipts. The committee have supplied 3,028 libraries at half price to national British, parochial, day, and Sunday schools, which were unable to pay the full amount. The total grants of libraries for various interesting objects amount to 6,055. The Society has translated, printed, and circulated works in the following languages: Northern Europe. — Icelandic, Swedish, Lapponese, Finnish, Danish, Norwegian. Southern Europe. — French, German, Latin, Roraanese, Enghadin, Italian, Maltese, Modern Greek, Albanian, Turkish, Turkish in Greek character, Turkish in Armenian character, Moldavian, Bulgarian, Syriac. China and Indo-Chinese Countries. — Chinese, Assamese, Shyam, Nagas, Burmese, Peguan, Talung, Karen, Siamese, Laos, Cambodian, Cochin-Chinese, Loo-Chooan, Japanese, Corean, er ring, 2, at the lower end of the rod, /, of which the other end is hung to the hook, w, upon the mantel beam, n. On the upper end of t, the handle, s, is fixed for turn- ing round continuously the vessel, K, while the fire is burning in the furnace, the fuel being put not only in its bottom chamber, but also into the holes, F, o {fg. 1049). The fire-wood is made very dry before ., . , « , « , , , , being used, by piling it in logs upon the iron bars, 2, 10, 11, under the manteli)ieeo, as shown in /^«, 1049, 1050. After the operation is finished, and the cover, n, is removed, the drum u emptied of Its contents, as follows. Upon the axle, /, there is toward k a projection at «. Alonir. side the furnace (/g. 1049) there is a crane, m, that turns upon the step ,, ,, on the ground. The upper pivot turns in a hole of the mantel-beam, f(. Upon the perpen- aicular arm, w, of the crane there is a hook, y, and a ring, , Tt.' Pelzwerk, Germ.), is nearly synonymous with fur, and comprehends the skins of different kinds of wild animals that are found in high northern latitudes, particularly in the American continent ; such as the beaver bear moosedeer, marten, mink, sable, wolverine, wolf, &c. When these skins have received no preparation but from the hunters, they are most properly called peltry ; but when they have had the inner side tawed or tanned (see Leathek) by an aluminous process, they may then be denominated /ttr*. ' ' The scouring or cleaning of peltry is performed in a large cask, or truncated cone laid on Its side, and traversed by a revolving shaft, which is furnished with a few rectangular rounded pegs. These are intended to stir round the skins, while they are dusted over with Paris plaster, whitening, or sometimes sand, made as hot as the hand can bear. The bottom of the cask should be grated, to allow the impurities to lall out. The lustrage, which the cleansed skins next undergo, is merely a species of dyein? either topical, to modify certain disagreeable shades, or general, to impart a more beautiful color to the fur. Under the articles Dyeing, and the several colors, as also Hair and Morocco, sufficient instructions will be found for dveing fur. The mordants should be applied pretty hot by a brush, on the hair of the skin, sketched upon a solid table ; and after two or three applications, with drying between, the tinctorial infusions may be rubbed on m the same way. The hair must be freed beforehand from all greasi- ness, by lime water, or a weak solution of carbonate of soda ; then well washed Much nicety, and many successive applications of the dye-stuff, are sometimes requisite to brine out the desired shade. """8 Under Hat Manufacture, I referred to this article for a description of the process of «6cre/age, whereby the hairs of rabbit and hare skins are rendered fit for felting Dissolve 32 parts of quicksilver in 500 of common aquafortis; and dilute the solution with one half or two thirds of its bulk of water, according to the strength of the acid. K^^ti r !1"^ *?'.'* ^P*"" ^ **^^^ "^'^^ ^^^ ^*^'' ^'^« uppermost, a brush, made with the bristles of the wild boar, is to be slightly moistened with the mercurial solution, and passed over the smooth surface of the hairs with strong pressure. This application ? u A ''T.^If ^^^^''^l t'^nes in succession, till every part of the fur be equally touched, and ill about two thirds of the length of the hairs be moistened, or a little more, should they be rigid. In order to complete this impregnation, the skins are laid together ui pairs with the hairy sides in contact, put in this state into the stove-room. jind exposed to a h«it higher in proportion to the weakness of the meicnrial solution. The dr)'ing should be rapidly effected, otherwise the concentration of the nitrate will not take due effect in causing the retraction and curling of the hairs. No other acid, or metallic solution, but the above, has been found to answer the de Sired purpose of the hatmaker. After the hairs are properly secreled, they are plucked off by hand, or shorn off by a machine. PENCIL MANUFACTURE. {Crayms.fahnque de, Fr.; Bleistifte, verfertigung, Germ.) The word pencil is used in two senses. It signifies either a small hair brush employed by painters in oil and water colors, or a slender cylinder, of black lead or plum- bago, either naked or enclosed in a wooden case, for drawing black lines upon paper. The last sort, which is the one to be considered here, corresponds nearly to the French term crayon, though this includes also pencils made of differently colored earthy compo- sitions. See Crayon. The best black-lead pencils of this country are formed of slender parallelopipeds, cut out by a saw from sound pieces of plumbago, which have been previously calcined in close vessels at a bright red heat. These parallelopipeds are generally enclosed in cases made of cedar wood, though of late years they are also used alone, in peculiar pencil-cases, under the name of ever-pointed pencils, provided with an iron wire and screw, to pro- trude a minute portion of the plumbago beyond the tubular metallic ease, in proportion as it is wanted. In the year 1795, M. Conte, a French gentleman, well acquainted with the mechanical arts, invented an ingenious process for making artificial black-lead pencils of superior quality, by which he and his successor and son-in-law, M. Humblot, have realized large fortunes. Pure clay, or clay containing the smallest proportion of calcareous or silicious matter, is the substance which he employed to give aggregation and solidity, not only to plum- bago dust, but to all sorts of colored powders. That earth has the property of diminish- ing in bulk, and increasing in hardness, in exact proportion to the degree of heat it is exposed to, and hence may be made to give every degree of solidity to crayons. The clay is prepared by diffusing it in large tubs through clear river water, and letting the thin mixture settle for two minutes. The supernatant milky liquor is drawn off by a syphon from near the surface, so that only the finest particles of clay are transferred into the second tub, upon a lower level. The sediment, which falls very slowly in this tub, is extremely soft and plastic. The clear water being run off, the deposite is placed upon a linen filter, and allowed to dry. It is now ready for use. The plumbago must be reduced to a fine powder in an iron mortar, then put into a crucible, and calcined at a heat approaching to whiteness. The action of the fire gives it a brilliancy and softness which it would not otherwise possess, and prevents it from being affected by the clay, which it is apt to be in its natural state. The less clay is mixed with the plumbago, and the less the mixture is calcined, the softer are the pencils made of it ; the more clay is used the harder are the pencils. Some of the best pencils made by M. Conte, were formed of two parts of plumbago and thiee parts of clay ; others of equal parts. This composition admits of indefinite variations, both as to the shade and hardness ; advantages not possessed by the native mineral. While the traces may be made as black as those of pure plumbago, they have not that glistening aspect which often impairs the beauty of black-lead drawings. The same lustre may, however, be ob- tained by increasing the proportion of powdered plumbago relatively to the clay. The materials having been carefully sifted, a little of the clay is to be mixed with the plumbago, and the mixture is to be triturated with water into a'perfectly uniform paste. A portion of this paste may be tested by calcination. If on cutting the' indurated mass! particles of plumbago appear, the whole must be further levigated. The remainder of the clay is now to be introduced, and the paste is to be ground with a muller upon a porphyry slab, till it be quite homogeneous, and of the consistence of thin dough. It is now to be made into a ball, put upon a support, and placed under a bell glass inverted in a basin of water, so as to be exposed merely to the moist air. Small grooves are to be made in a smooth board, similar to the pencil parallelopipeds, but a little longer and wider, to^Uow for the contraction of volume. The wood must be boiled m grease, to prevent the paste from sticking to it. The above described paste being pressed with a spatula into these grooves, another board, also boiled in grease, is to be laid over them very closely, and secured by means of screw-clamps. As the atmo- spheric air can get access only to the ends of the grooves, the ends of the pencil-pieces become dry first, and by their contraction in volume get loose in the grooves, allowing the air to insinuate further, and to dry the remainder of the paste in succession. When Uie whole piece is dned, it becomes loose, and might be turned out of the grooves. But before this is done, the mould must be put into an oven moderately heated, in order to render the pencil pieces still drier. The mould should now be taken out, and emptied upon a table covered with cloth. The greater part of the pieces will be entire, and on.y a few will have been broken, if the above precautions have been dult observed. They are all, however, perfectly straight, which is a matter of the first im- portance. In order to give solidity to these pencils, they must be set upright in a crucible till -•^■ Ut see PENS, STEEL. PEPPER. 367 u H is filled with them, and then surrounded with charcoal powder, fine sand, or sifted wood ashes. The crucible, after having a luted cover applied, is to be put into a ft^rnace, and exposed to a decree of heat regulated by the pyrometer of Wedgewood ; which de<-ree is proportional to the intended hardness of the pencils. When they have been thus baked, the crucible is to be removed from the fire, and allowed to cool with the pencils in it. . . , , - ^ i- ^ Should the pencils be intended for drawing architectural plans, or for very fine lines, they must be immersed in melted wax or suet nearly boiling hot, before they are put into the cedar cases. This immersion is best done by heating the pencils first upon a grid-iron, and then plunging them into the melted wax or tallow. They acquire by this means a certain degree of softness, are less apt to be abraded by use, and preserve their points much better. , , . . . u v i- *i. When these pencils are intended to draw ornamental subjects with much shading, they should not be dipped as above. ,...«. ^^ ,. .- ah Secoiui process for making artificial pencih, somewhat different from the precedmg.---A\l the operations are the same, except that some lamp-black is introduced along with the plumbago powder and the clav. In calcining these pencils in the crucible, the contact of air must be carefully excluded, to prevent the lamp-black from being burned away on the surface. An indefinite variety of pencils, of every possible black tint, may thus be produced, admirably adapted to draw from nature. Another ingenious form of mould is the following : . Models of the pencil-pieces must be made in iron, and stuck upright upon an iron tray, having edges raised as hi-h as the intended length of the pencils. A metallic alloy is made of tin, lead, bismuth, and antimony, which melts at a moderate heat. This is poured into the sheet-iron tray, and after it is cooled and concreted, it is inverted, and shaken off from the model bars, so as to form a mass of metal perforated throughout with tubular cavities, corresponding to the intended pencil-pieces. The paste is in- troduced by pressure into these cavities, and set aside to dry slowly. When nearly dry, the pieces get so much shrunk that they may be readily turned out of the moulds upon a cloth table. They are then to be completely desiccated in the shade, afterwards in a stove-room, next in the oven, and lastly ignited in the crucible, with the precautions above M. Conte recommends the hardest pencils of the architect to be made of lead melted with some antimony and a little quicksilver. a 4V. * *r. In their further researches upon this subject, M. Conte and M. Humblot lound that the different degrees of hardness of crayons could not be obtained in a uniform manner ^y the mere mixture of plumbago and clay in determinate doses. But they discovered a remedy for this defect in the use of saline solutions, more or less concentrated, into which they plunged the pencils, in order to modify their hardness, and increase the uniformity of their texture. The non-deliquescent sulphates were preferred for this purpose ; such as sul- phate of soda, &c. Even sirup was found useful in this way. . ^ ^ Messrs. Stevens and Wylder's pencils, pens, and pen AoW^a— Messrs. Stevens A Wylder obtained a patent in June, 1850, for certain improvements, in which they claini, 1 (In respect of ever pointed pencils.) The employment of an internal helix in lieu of a propelling screw, by means of which a length of black lead, chalk, or other marking materials may be propelled nearly the whole length of the pencil. 2. (With reference to pens.) The application of gutta percha to metal pens, be- tween the shoulder and the nibs, the metal having been farst reduced m thickness, either bv grinding or otherwise, for the purpose of obtaining greater flexibility. 2ndlv The construction of barrel and other pens in metal, to be used with fountain pen holders, having the ban-el placed the reverse way, or above instead of below the nibs. 3. (With respect to penholders.) Ist. The use and application of glass to telescopic and other fountain holders, whereby the ink is kept from contact with metal until it reaches the pen. (Query, has not this been anticipated by Mr. Thomson s patent?) 2ndly. The adaptation of a band of flexible material to fountain holders, for the pur- pose of facilitating the flow of ink to the pen, such band being placed around a part of the tube, in which air holes or openings have been previously made. PENS STEEL. The best metal, made from Dannemora or hoop (l) iron, is selected and laminated into slips about 3 feet long, and 4 inches broad, of a thickness corre- sponding to the desired stiffness and flexibility of the pens. These slips are subjected to the action of a stamping-press, somewhat similar to that for making buttons. (See Button and Plated Ware.) The point destined for the nib is next introduced into an appropriate gauged hole of a little machine, and pressed into the semi-cylindncal shape • where it is also pierced with the middle slit, and the lateral ones, provided the latter are to be given. The pens are now cleaned, by being tossed about among each other in a tin cylinder, about 3 feet long, and 9 inches in diameter; which is suspended at each end upon joints to two cranks, formed one on each of two shafts. The cylm- •3er, by the rotation of a fly-wheel, acting upon the crank-shafts, is made to describe such revolutions as agitate the pens in all directions, and polish them by mutual attri- tion. In the course of 4 hours several thousand pens may be finished upon this machine. When steel pens have been punched out of the softened sheet of steel by the appro- priate tool, fashioned in the desired form, and hardened by ignition in an oven and sudden quenching in cold water, they are best tempered by being heated to the re- quisite spring elasticity in an oil bath. The heat of this bath is usually judged of by the appearance to the eye ; but this point should be correctly determined by a ther- mometer, according to the scale (see Steel); and then the pens would acquire a definite degree of flexibility or stiffness, adapted to the wants and wishes of the con- sumers. They are at present tempered too often at random. Gillott, Joseph^ Victoria Works, Birmingham, Inventor and Manufa^iturer. Specimen* of metallic pern. Steel pen making may be briefly described as follows : The steel is procured at Sheffield ; it is cut into strips, and the scales removed by immersion in pickle com.posed of dilute sulphuric acid. It is passed through rollers, by which it is reduced to the necessary thickness ; it is then in a condition to be made into pens, and is for this purpose passed into the hands of a girl, who is seated at a press, and who by means of a bed and a punch corresponding speedily cuts out the blank. The next stage is piercing the hole which terminates the slit and removing any superfluous steel likely to interfere with the elasticity of the pen ; at this stage they are annealed in quantities in a muffle, after which by means of a small stamp the maker's name is im- pressed upon them. Up to this stage the future pen is a flat piece of steel : it is then transferred to another class of workers, who by means of the press make it concave, if a nib, and form the barrel, if a barrel pen. Hardening is the next process : to effect this a number of pens are placed in a small iron box and introduced into a muffle ; after they become of a uniform deep red, they are plunged into oil ; the oil adhering is re- moved by agitation in circular tin barrels. The process of tempering succeeds ; and finally the whole are placed in a revolving cylinder with sand, pounded crucible, or other cutting substances, which finally brightens them to the natural colour of the ma- terial. The nib is ground with great rapidity by a girl who picks it up, places it in a pair of suitable plyers, and finishes it with a single touch on a small emery wheel The pen is now in a condition to receive the slit, and this is also done by means of a press ; a chisel or wedge with a flat side is fixed to the bed of the press ; the de- scending screw has a corresponding chisel cutter, which passes down with the minutest accuracy; the slit is made ; and the pen is completed. The last stage is colouring brown or blue ; this is done by introducing the new pens into a revolving metal cylin- der, under which is a charcoal stove, and watching narrowly when the desired tint is arrived at. The brilliancy is imparted by means of lac dissolved in naphtha ; the pens are immersed in this, and dried by heat Then follow the counting and selecting. Women are mostly employed in the manufacture, with skilled workmen to repair and set the tools. This exhibitor employs upwards of five hundred hands, of which four- fifths are women. The manufactory has been established upwards of thirty years, and has been the means of introducing many improvements in the manufacture. Wiley, W. E. ^^^^^^ Tnd dimensions. Sago, being the mill, retain, in like circumstances, ^J^^^j^^^f^X ,^ palm in a damp state, upon pearled by heating and stirring the ^^^ J ""'^^^^^^^^^^ aggregation and brilliant bac?. lilUnVp" sU^^tn's^^^^^^^^^ -' '-^' " Vhf ESaTs'arsufficiently odious and oppressive in themselves without being aggravated by the servile sophistry of pseudo-science. ^^ ^^^ '^lour pounds of ^ack pepper y eld ^^^^^^^^^ led from it afterward, by potash. Imported. lbs. 8,082,319 3,99G,496 Retained for Con- Bumptioa. lbs. 3,174,425 3,303,402 Exported. lbs. 3,'727,183 2,709,755 Duty received. £ 83,324 86,729 PERCUSSION CAPS. Pa*«.. ^^^YtsS^^tr^-^"^- ing guns in Europe may be «f'"»'4**VoA^'ZtiIyot copper requisite for ite portance of this article may be f"™^*;™" 'j Xantages of the percussion princi- production, yiz. 396,000 lbs. weight The f/^*''^S^' the short space of 20 years all L have been 'ogen^^^^^^^n 'aLtnatdlhtpe'reussion Jtom has stated to be remarkable for accuracy «"^^!'l"»'^'y ereSn caps coated with varnish :Krd°i7rrJin^i.^'rel^ *'"'' ^^ »' '^X^%}^^ClJr^nr^^o..e, a - '-trrp^aTtCp-Zse-tr from penetrating between the percussion caps and the nipple, ana x.u f ntRTimS^'ART^^^^^^^ Fr.; Wohlriechende-kunst, Germ.); consiste tilled spirits, pastes, pastilles and essences. PERFUMERY, ART OF. 369 Fats ought to be pounded in a marble mortar, without addition of water, till all the membranes be completely torn ; then subjected to the heat of a water -bath in a propCT vcesel. The fat soon melts, and the albumen of the blood coagulating, carries with it all the foreign substances ; the liquid matter should be skimmed, and passed through a canvass filter. 0/ pommades by infasion. — Rose, orange-flower, and cassia. Take 334 pounds of hog's lard, and 166 of beef suet. These 500 pounds are put into a pan called bugadier ; and when melted, 150 pounds of rose-leaves nicely plucked are added, taking care to stir the mixture every hour. The infusion thus prepared is to remain at rest for 24 hours ; at the end of this time, the pommade is again melted, and well stirred to prevent its adherence to the bottom of the melting-pan. The mass is now to be poured out into canvass, and made into rectangular bricks or loaves, which are subjected to a press, in order to separate the solid matter from the soft pommade. These brick-shaped pieces being put into an iron-bound barrel perforated all over its staves, the pommade is to be allowed to exude on all sides, and flow down into a copper vessel placed under the trough of the pxess. This manipulation should be repeated with the same fat ten or twelve times ; or in other words, 3000 pounds of fresh rose-leaves should be employed to make a good pommade. The pommade of orange-flowers is made in the same manner, as also the pommade of cass:.a. 0/ pommades vnihoat infusion. — Jasmine, tuberose, jonquil, narcissus, and violet. A square frame, called tiame, is made of four pieces of wood, well joined together, 2 or 3 inches deep, into which a pane of glass is laid, resting upon inside ledges near the bottom. Upon the surface of the pane the simple pommade of hog's lard and suet is spread with a pallet knife ; and into this pommade the sweet-scented flowers are stuck fresh in diHcrcTit points each successive day, during two or three months, till the pommade has acquired the desired richness of perfume. The above-described frames are piled closely over each other. Some establishments at Grasse possess from 3000 to 4000 of 0/ oils. — Rose, orange-flower, and cassia oils, are made by infusion, like the pom- mades of the same perfumes ; taking care to select oils perfectly fresh. As to those of jasmine, tuberose, jonquil, violet, and generally all delicate flowers, they are made in the following manner. Upon an iron frame, a piece of cotton cloth is stretched, imbued with olive oil of the first quality, and covered completely with a thin bed of flowers. Another frame is similarly treated, and in this way a pile is made. The flowers must be renewed till the oil is saturated with their odor. The pieces of cotton cloth are then carefully pressed to extrude the oil. This last operation requires commonly 7 or 8 days. Of distillation. — ^The essential oils or essences, of which the great manufacture is in the south of France, are of rose, neroli, lavender, lemon thyme, common thyme, and rose- mary. For the mode of distilling the essential oils, see Oils, essential. The essence of roses being obtained in a peculiar manner, I shall describe it here Put into the body of a still 40 pounds of roses, and 60 quarts of water ; distil oflf one half of the water. When a considerable quantity of such water of the first distillation is obtained, it must be used as water upon fresh rose-leaves ; a process of repetition to be carried to the fifth time. In the distillation of o*Tinge-flower, to obtain the essence of neroli, the same process is to be followed ; but if orange-flower water merely be w^anted, then it is obtained at one distillation, by reserving the first fifth part of water that comes over. What is called the essence of petit-grain, is obtained by distilling the leaves of the orange shrub. The essences of lavender, thyme, &c., present nothing peculiar in theit mode of extraction. OF SCENTED SPIRITS, From oil of rose, orange, jasmine, tuberose, cassia, violet, and other flowers. Into each of three digesters, immersed in water-baths, put 25 lbs. of any one of these oils, and pour into the first digester 25 quarts of spirit of wine ; agitate every quarter of an hour during three days and at the end of this period, draw oflf the perfumed spirit, and Esprit de Suave. 7 Eng. qrts. of spirit of jasmine,3d operation. 7 — cassia, — 8 — wine. 2 — tuberose, — IJ ounce essence of cloves. I ounce fine neroli. 1 J ounce essence of bergamot. 8 ounces essence of musk, 2d infusion. 3 quarts rose water. Spint of Cytfierea^ 1 quart spirit of violets. 1 1 1 1 1 2 jasmine, 2d operation. tuberose, clove gillyflower. roses, 2d operation. Portugal. orange-flower water 'V [11 in 870 PERFUMERY, ART OF. pour it into the second digester ; then transfer it after 3 days into the third digester, treating the mLxture in the same way ; and the spirit thus obtained will be perfect. The digesters must be carefully covered during the progress of these operations. On pursuing the same process with the same oil and fresh alcohol, essences of inferior qualities may be obtained, called Nos. 2, 3, and 4. Some perfumers state that it is better to use highly scented iommades than oilflj out there is probably little difference in this respect. Spirit of flowers of Italy. 2 quarts spirit of jasmine, 2d operation. 2 — roses, 2 — oranges, 3d The above spirits mark usually 28 alcometric degrees of Gay Lussac. 2 quarts spirit of cassia, 2d operation. ]| — orange flower water. See Alcohol. POMMADES. No less than 20 scented pommades are distinguished by the perfumers of Paris. The essences commonly employed in the manufacture of pommades, are those of bergamot, lemons, cedrat, Hmette (sweet lemon), Portugal, rosemary, thyme, lemon thyme, lavender, marjoram, and cinnamon. The following may serve as an example : — Pammade ti la vanille, commonly called Roman. 12 pounds of pommade a la rose. 3 — oil a la rose. 1 — vanilla, first quality, pulverized. 6 ounces bergamot. The pommade being jnelted at the heat of a water-bath, the vanilla is to be introduced with continual stirring for an hour. The mixture is left to settle during two hours. The pommade is then to be drawn off, and will be found to have a fine yellow color, in* stead of the brown shade which it commonly has. In making odoriferous extracts and waters, the spirits of the flowers prepared by macerating the flowers in alcohol should be preferred to their distillation, as forming the foundation of good perfumery. The specific gravity of these spirits should be always under 0-88. Extract of Nosegay (bouquet). 2 quarts spirit of jasmine, 1st operation. — extract of violets. — spirit of cassia, 1st — — roses, - 1st — — orange, - 1st — — Extract of clove gillyflower. 4 drms. of flowers of benzoin (benzoic acid). 8 ounces of essence of amber, 1st infusion. Extract of peach hlossoms. 6 quarts of spirits of wine. 6 pounds of bitter almonds. 2 quarts of spirits of orange flower, operation. 4 drachms of essence of bitter almonds. 4 drachms of balsam of Peru. 4 ounces of essence of lemons. 2d Eau de Cologne. Two processes have been adopted for the preparation of this perfume, distillation and infusion; the first of which, though generally abandoned, is, however, the preferable one. The only essences which should be employed, and which have given such celebrity to this water, are the following; bergamot, lemon, rosemary, Portugal, neroli. The whole of them ought to be of the best quality, but their proportions may be varied according to the taste of the consumers. Thirty different odors are enumerated by perfumers ; the three following recipes will form a sufficient specimen of their combinations. Honey-water. 6 quarts of spirit of roses, 3d operation. 3 do jasmine. 3 do. spirits of wine. 3 ounces essence of Portugal. 4 drachms flowers of benzoin. 12 ounces of essence of vanilla, 3d infusion. 12 do. musk, do. 3 quarts good orange- flower water. Eau de mille fleurs. 18 quarts of spirits of wine. 4 ounces balsam of Peru. 8 do. essence of bergamot. 4 do. cloves. 1 do. ordinary neroli. 1 do. thyme. 8 do. musk, 3d infusion. 4 quarts orange flower water. PERFUMERY, ART OF. Eau de mousseline^ 371 2 ounces essence of vanilla, 3d infusioi. 2 do. musk, do. 4 drachms of sanders wood. 1 quart of orange-flower water. 2 qnarts spint of roses, 3d infusion. Z do. jasmine, 4th do. 1 do. clove gillyflower. 2 do. orange flower, 4th do jUmond pastes. These are, gray, sweet white, and bitter white. The first is made either with the kernels of apricots, or with bitter almonds. They are winnowed, ground, and formed into loaves of 5 or 6 pounds weight, which are put into the press in order to extract their oil ; 300 pounds of almonds affording about 130 ot oil. The pressure is increased upon them every two hours during three days ; at the end of which time the loaves or cakes are taken out of the press to be dried, ground, and sifted. ', The second paste is obtained by boiling the almonds in water till their skins are com- pletely loosened ; they are next put into a basket, washed and blanched ; then dried, and pressed as above. The third paste is prepared like the second, only using bitter almonds. Liquid almond pastes, such as those of the rose, orange, vanilla, and nosegay. The honey paste is most admired. It is prepared as follows ; — 6 pounds of honey. I 12 pounds oil of bitter almonds. 6 do. white bitter paste. j 26 yolks of eggs. The honey should be heated apart and strained; 6 pounds of almond paste must then be kneaded with it, adding towards the conclusion, alternately, the quanv'Xy of yolks of eggs and almond oil indicated. Pastilles d la rose, orange flower, and vanilla. Pastilles of orange flx)wer, 12 ounces of gum galbanum. 12 do. olibanum, in tears. 12 do. storax, do. 8 do. nitre. 1 pound of pure orange powder. 3 do. 14 ounces charcoal powder. 1 ounce superfine neroli. Pastilles d la vanille. Pastilles h la rose. 12 ounces of gum. 12 do. olibanum, in tears. 12 do. storax, do. 8 do. nitre. 16 do. powder of pale roses. 3 pounds 14 do. charcoal powder. 1 do. essence of roses. 16 ounces powder of vanilla. 3 pounds 14 ounces charcoal powder. 4 drms. essence of cloves. 8 ounces do. vanilla, 1st infusion. 12 ounces of gum galbanum. 12 do. olibanum, in tears. 12 do. storax do. 8 do. nitre. 8 do. cloves. The above mixture in each case is to be thickened with 2 ounces of gum tragacantk dissolved in 2 pints of rose water. It is needless to say that the ingredients of the mix- ture should be impalpable powders. Scented cassolettes. 8 pounds of black amber (ambergris). 4 do. rose powder. 2 ounces of benzoin. 1 ounce essence of roses. 1 do. gum tragacanth. A few drops of the oil of sanders wood. These ingredients are pulverized,. and made into a cohesive paste with the gum. ESSENCES BY INFUSION. Essence of musk. 5 ounces of musk from the bladder, cut small. 1 do. civet. 4 quarts of spirit of ambrette (purple sweet sultan). The whole are put into a matrass, and exposed to the sun for two months dnring the hottest season of the year. In winter, the heat of a water bath mnst be r» sorted to. I i' 372 PERFUMERY. PERSONAL CLOTHING. 373 i Essence of vanUla. 8 pounds of vanilla in branches, lat quality, cut small. 4 quarts spirit of ambrette. 2 arachms of cloves. ■J do musk from the bladder. Tte same process must be followed as for the essence of musk. Essence of ambergris. 4 ounces of ambergris, 2 ounces of bladder musk. 8 quarts of spirit of ambrette. Treat aa above. /Spirit of ambrette (purple sweet sultan). 25 pounds of ambrette are to be distilled with 25 quarts of spirits of wine, adding 12 quarts of water, so as to be able to draw off the 25 quarts. Artificial Essences of Fruits in the Exhibition. The artificial production of aro- matic oils, for industrial objects, can only be traced back a few years. Young, however, as this manufacture is, it appears, nevertheless, to have been in the hands of several distillers, by whom a very considerable amount has been produced. Upon this point the jury became fully convinced by their investigations in this department ; both in the English and in the French divisions of the Exhibition a large selection of these chemical perfumeries were to be found, the comparison of which at the same time with other aromatic preparations was satisfactorily illustrated. Most of these oils are poisonous in small quantities, so that in very few instances can their action be asserted without fresh investigations. • « -j The commonest of these preparations was the pear-oil (Birnol), a favourite fluid, which, by examination, is proved to be an alcoholic solution of acetate of the oxide of amyle. As the author had not sufficient of this satisfactorily to determine its com- position by its combustion, he mixed it with potash, by which means fusel oil was im- mediately liberated, and the acetic acid was separated in the form of salt of silver, of which 0-3089 grammes gave 0-1994 grammes silver ; the percentage of silver in the acetate being theoretically 64-68, by experiment 6455. The acetate of oxide of amvle made ac- cording to the usual process (1 part sulphuric acid, 1 part fusel oil, and 2 parts of acetate of potash^ presents a strong fruity odour, and by the addition of about 6 parts of alcohol, yields the flavour of jargonelle pear. Upon closer inquiry of the manufacturers of this substance the author found that it was produced in very considerable quantities (by some between 15 and 20 lbs, weekly). In England it is extensively employed in flavouring * pear-drops,' which have almost superseded the common • barley-sugar drops.' Next to the " pear" oil, figures Apple oil, which experiment has shown to be nothing more than a valerianate of oxide of amyle, which yields an insupportable odour of rotten apples, pervading the laboratory where valerianic acid is produced. If the crude pro- duct of distillation be treated with a solution of potash, the valerianic acid is removed and the ether is retained ; the addition to this of 5 or 6 times its volume of alcohol gives oflf an agreeable odour of aj)ples. The essence, however, which was observed to be in the greatest abundance was the " Pine Apple oil" which is simply a butyrate of oxyde of ethyle. This composition, like the two preceding, yields its flavour on the addition of alcohol. The butyric ether, which in Germany la added to inferior sorts of rum, for the purpose of imparting a flavour to a peculiar kind of drink (pine apple ale), is seldom prepared for this pur- pose from pure butyric acid, but from the saponified acid, and the distillation of the soap with concentrated sulphuric acid and alcohol (vide Annalen der Chemie und Fharmacie, xlix. 359.) The fluid thus obtained contains other kinds of ether besides butyric ether, but may, without these, be employed for flavouring. The analysis of this ether by means of potash and a salt of silver, gave 0*4404 gr. of salt of silver ; 0-2437 silver ; the percentage of silver in its butyrate being, theoretically, 55-38, experimen- tally, 55-33. The so-called Cognac oil and Grape oil were contributed to both the English and French departments. They are most frequently employed for giving the cognac flavour to brandies. The grape oil consists of a compound of amyle dissolved in alcohol, then set free by the addition of concentrated sulphuric acid; the oil of sulphate of amyle is then freed from alcohol by washing with water. Analysed by means of a salt of barium 1*2690 gr. amyl-sulphate of baryta gave 0-5815 gr. of sulphate of baryta, equal to 45*82 per cent, of sulphate of baryta. According to Cahours, and again more lately, according to Kekule, the analysis of amyl-sulphate of baryta with 2 eq. of water, contains 49*96 per cent, of sulphate of baryta. It is certainly remarkable, as has been observed, that we have here a body, which is most carefully excluded from brandy, en account of its intolerable odour, employed again under another form to give it flavour. The next object of attention is the artificial oil of bitter almonds. When Mitscherlich, in 1834, discovered nitro-benzule, he did not foresee the great amount in which this body would be found in an Industrial Exhibition. It is true he had observed the remark- able similarity of its odour to that of oil of bitter almonds, but then the only source whence the nitro-benzule could be obtained, viz., from the oil of compressed gases, and the distillation of benzoic acid, were too costly to admit of the idea of its employment as a substitute for oil of bitter almonds. It remained for the author, in 1845, to detect the presence of benzule in the transformation of coal tar ; and in 1849, Mansfield (Chmncal Society's Quarterly Journal, i., 244.; Annalen, Ixix 162.) showed that it could be obtained with facility in considerable quantities from coal tar. The Great Exhibition has shown that this statement has not been lost sight of In the French department of perfumery, it was met with under the designation of artificial oil of bit- ter almonds, and under the fantastic name of essence of rairbane, varieties of the oil "which, on examination, were found to be more or less pure nitro-benzule. In London it is used in large quantities. Messrs. Mansfield's simple apparatus for its preparation is thus described : — A large glass worm is used, the upper end of which is bifurcated, and forms two tubes of a funnel shape ; into one of these funnels concentrated nitric acid is poured, in the other the benzule ia placed (and for thia purpoae it is not required to be absolutely pure). The two bodies, therefore, meet at the point of junction of these two tubes, the compound is cooled by its course through the windings of the worm, and requires only to be washed with water or diluted solution of carbonate of soda, and it is then fit for use. Although nitro-benzule has an odour so closely resembling oil of bitter almonds, a difference may be detected by an experienced nose. It is, how ever, very generally employed in scenting soaps, in confectionery, and for culinary pur- poses. For the last named purpose it has the advantage of not containing hydrocyanic acid. Besides the preceding, many other substances of analogous nature were exhibited, but they were of too complicated characters to be satisfactorily examined in the small <5^uantitie8 to be met with. In many of these essences there was, however, a great similarity of aroma. PERFUMERY, INDIAN. The natives place on the ground a layer of the scented flowera, about 4 inches thick and 2 feet square ; cover them over with a layer 2 inches thick of Tel or Sesamum seed wetted ; then lay on another 4 inch bed of flowera, and cover this pile with a sheet, which is pressed down by weights round the edges. After remaining in this state for 18 hours, the flowei*s are removed and replaced by a similar fresh layer, and treated as before ; a process which is repeated a third time if a very rich perfumed oil be required. The sesamum seeds thus imbued with the essential oU of the plants whether jasmine, Bela, or Chumbul, are placed in their swollen state in a mill, and subjected to strong pressure, whereby they give out their bland oil strongly impregnated with the aroma of the particular flower employed. The oil ia kept in prepared skins called dubbers, and is largely used by the Indian women. The attar of roses is obtained by distillation at a colder period of the year. PERRY, is the fermented juice of pears, prepared in exactly the same way as Cydeb. PERSIAN BERRIES. See Berries, Persian. PERSONAL CLOTHING. The title of the class will suggest the multifarious ob jects which fall naturally within its comprehensive limits. The sub-classes are as fol- lows : — A hat^ caps, and bonnets of various materials ; B. hosiery, of cotton, woollen, and silk ; C. gloves of leather and other materials ; D. boots, shoes, and lasts ; E. under- clothing; F. upper-clothing. The manufactories of hosiery, straw plait, and boots and ahoes, have a local establish- ment in this country, which is deserving of attention ; that of hosiery is principally confined to Derby, Nottingham, and Leicester. Cotton hosiery is chiefly made in Not- tingham, as also is the silk hosiery; the latter being likewise largely conducted in Derby. Woollen hosiery is most extensively produced in Leicestershire. The statistics of these tradea have been carefully prepared and are very intereating. The annual value of cotton hosiery is taken at 880,000/., that of worsted, i ' li. 374 PHANTASMAGORIA. Gloves are of great antiquity in this island, as the word is evidently derived from the Anglo-Saxon " glof " They are not mentioned in Scripture, but were in use among the Romans in the time of Pliny the Younger. Xenophon states that their use among the Persians was considered a proof of their luxurious habits. Gloves have had many symbolical meanings. The gauntlet or glove thrown down was a mode of challenge, and still is practised as one of the forms of royal coronation. Queen Elizabeth, it is well known, was verj' fond of gloves, of which numerous presents were made to her. White gloves are also presented to the judges on occasion of a maiden assize, the exact significance or origin of which practice has never b«6n satisfactorily explained. Leather gloves are now made at Worcester, Yeovil, Woodstock, and London, and were formerly made at Jjeominster and Ludlow, but the trade in the latter places is quite decayed. Plait straw is the straw of the wheat plant, selected especially from crops grown on dry chalky lands, such as those about Dunstabla The middle part of the straw above the last joint is selected ; it is cut into lengths of eight or ten inches, and these are then split The Leghorn or Tuscan is the straw of a variety of bearded wheat, grown expressly on poor sandy soils, pulled when green, and then bleached. Other kinds of the grass tribe besides wheat ftirnish straws available for plait-work. PETROLEUM. See Naphtha. PE-TUNT-SE, is the Chinese name of the fusible earthy matter of their porcelain. It la analc^ous to our Cornish stone. PEWTER, PEWTERER. (Potier d'iiain, Fr.) Pewter is, generally speaking, an alloy of tin and lead, sometimes with a little antimony or copper, combined in several different proportions, according to the purposes which the metal is to serve. The English tradesmen distinguish three sorts, which they call plate, trifle, and ley pewter ; the first and hardest being used for plates and dishes ; the second for beer-pots ; and the third for larger wine measures. The plate pewter has a bright silvery lustre when polished ; the best is composed of 100 parts of tin, 8 parts of antimony, 2 parts of bismuth, and 2 of copper. The trifle is said by some to consist of 83 of tin, and 17 of antimony ; but it generally contains a good deal of lead. The ley pewter is composed of 4 of tin, and 1 of lead. As the tendency of the covetous pewterer is always to put in as much of the cheap metal as is compatible with the appearance of his metal i'* the market, and as an excess of lead may cause it to act poisononsly upon all vinegars and many wines, the French government long ago appointed Fourcroy, Vauciuelin, and other chemists, to ascertain by experiment the proper proportions of a safe pewter alloy. These commissioners found that 18 parts of lead might, without danger of affecting wines, &c., be alloyed with 82 parts of tin ; and the French government ia consequence passed a law requiring pewterers to use 83| of tin in 100 parts, with a tolerance of error amounting to 1| per cent. This ordonnance, allowing not more than J 8 per cent, of lead at a maximum, has been extended to all vessels destined to contain alimentary substances. A table of specific gravities was also published, on purpose to test the quality of the alloy ; the density of which, at the legal standard, is 7-764. Any excess of lead is immediately indicated by an increase in the specific gravity above that number. The pewterer fashions almost all his articles by casting them in moulds of brass or bronze, which are made both inside and outside in various pieces, nicely fitted together, and locked in their positions by ears and catches or pins of various kinds. The moulds must be moderately heated before the pewter is poured into them, and their surfaces should be brushed evenly over with pounce powder (sandarach) beaten up with while of egg. Sometimes a film of oil is preferred. The pieces, af\er being cast, are turned and polished ; and if any part needs soldering, it must be done with a fusible alloy of tin, bismuth, and lead. Britannia metal, the kind of pewter of which English tea-pots are made, is said to be an alloy of equal parts of brass, tin, antimony, and bismuth ; but the proportions diflei in difl'erent workshops, and much more tin is commonly introduced. Queen's metal is said to consist of 9 parts of tin, 1 of antimony, 1 of bismuth, and 1 of lead ; it serves also for teapots and other domestic utensils. A much safer and better alloy for these purposes may be compounded by adding to 100 parts of the French pewter, 5 parts of antimony, and 5 of brass to harden it. The English ley pewter contains often much more than 20 per cent, of lead. Under TiH, wifl be found the description of an easy method of analyzing its lead alloys. PHANTASMAGORIA. The phantasmagoria lanterns are a scientific form of magio lantern, differing from it in no essential principle. The images they produce are variously exhibited, either on opaque or transparent screens. Tlie light is an improved kind of solar lamp. The manner in which the beautiful melting pictui-es called dissolving views are produced, as respects the mechanism employed, deserves to be explained. The PHARMACEUTICAL PRODUCTS. 375 arrangement adopted in the instrument is the following : — ^Two lanterns of the same •ize and power, and in all respects exactly agreeing, are arranged together upon a little tray or platform. They are held fast to this stand by screws, which admit of a certain degree of half-revolving motion from side to side, in order to adjust the foci. This being done in such a manner that the circle of light of each lantern falls precisely upon the same spot upon the screen, the screws are tightened to the utmost extent so as to remove all possibility of further movement. The dissolving apparatus consists of a circular tin plate japanned in black, along three parts of the circumference of which a crescented aperture runs, the interval between the horns of the crescent being occupied by a circular opening, covered by a screwed plate, removable at pleasure. This plate is fixed to a horizontal woodeu axis, at the other end of which is a handle, by which the plate can be caused to rotate. The axis of wood is supported by two pillars connected with a flat piece which is secured to the tray. This apparatus is placed between the lanterns in such a manner that the circular plate is in front of the tubes of both, while the handle projects behind the lanterns at the back. The plate can, therefore, be turned round by means of the handle without difficulty, from behind. A peg of wood is fixed into the axifl> eo as to prevent its effecting more than half a revolution. The widest part of the eresceutic opening in the plate is sufficient to admit all the rays of the lantern before which it happens to be placed- On the plate being slowly turned half round, by means of the handle behind, the opening narrows until it is altogether lost in one of the horns of the crescent. The light of that lantern is gradually cut off as the aperture diminishes, until it is at length wholly shaded under the moveable cover occupying the interval between the horns of this crescentic opening. In proportion as the light is cut off from one, it is let on from the other tube, in consequence of the gradually increasing size of the crescent revolving before it, until at length the widest part of this opening in the plate is pre- sented before the tube of the second lantern, the first being, as we have seen, shaded. This movement being reversed, the light is cut off from the second lantern, and again let on from the first, and so on alternately. Thus while the screen always presents the same circle of light, yet it is derived first from one lantern, then from the next. When in use a slider is introduced into each lantern. The lantern before the mouth of which the widest part of the opening in the plate is placed, exhibits the painting on the screen, the light of the other lantern being then hid behind the cover. On turning the handle, this picture gradually becomes shaded, while the light frona the second lantern streams through the widening opening. The effect on the screen is the melting away of the first picture, and the brilliant development of the second, the screen being at no instant left unoccupied hy a picture. The principle involved in this apparently complex, but in reality simple mechanism, is, merely the obscuration of one picture, and the throwing of a second in the same place on the screen. And it may be accomplished in a great variety of ways. Thus by aimply placing a flat piece of wood, somewhat like the letter Z on a point in the centre, so that alternately one or the other of the pieces at the end should be raised or depressed before the lanterns, a dissolving scene is produced. Or, by fixing a moveable upright shade, which can be pushed alternately before one or the other of the lanterns, the same effect is produced. Individuals exist in this metropolis whose sole occupation consists in painting the minute scenes or slides used for the phantasmagoria lanterns. The perfection to which these paintings are brought is surprising. There are two methods by which the sliders now emplo^-ed are produced. In one of these, the outline and detail are entirely the work of the artist's pencil. For pictures representing landscapes, or wherever a spirited painting is required, this is the exclusive method employed. The colours are rendered transparent by being ground in Canada balsam and mixed with varnish. The other method is a transfer process. The outlines of the subject are engraved on copper plates, and the impression is received from these on thin sheets of glue, and is then transferred to a plate of glass, the impression being burnt in the same manner as ia effected in earthenware. Sliders produced in this way receive the distinctive name of copper plate sliders. The subject is merely represented in outline, it being left to the artist to fill up with the necessary tints, ' acid, and incapable of communicating any taint to its contents. These casks form, by their non- conducting quality as to heat, the best kind of steam-jackets. In these pans the vine- gars with their compounds are heated, and the fish and other sauces are prepared. (^ 884 PIMENTO. PIN MANUFACTURE. 385 1 t 1 1 The waste steam at the farthest extremity of the pipe is conducted into a reservoir of clean water, so as to farnish a constant supply of hot water for washing bottles and utensils. The confectionary and ham-smoking compartments are placed in a separate fireproof chamber on the same floor. The floor above is occupied along the sides with a range of large rectangular cast iron cisterns, furnished with a series of steam-pipes, laid gridironwise along their bot- toms, which pipes are covered with a perforated wooden shelf. These cisterns being filled up to a certain height above the shelf with water, the bottles full of green goose- berries, apricots, cherries, &c., to be preserved, are set upon the shelf, and the steam being then admitted into the gridiron pipes, the superjacent water gets gradually heated to the boiling point ; the air in the bottles round the fruit is thus partly expelled by expansion, and partly disoxygenated by absorption of the green vegetable matter. In this state the bottles are tightly corked, and being subsequently sealed, preserve the fiuit fresh for a very long period. The sauces, pastes, and potted meats, prepared in the above-described apparatus, can seldom be rivalled and probably not surpassed in the kitchens of the most fastidious gastronomes. PICROMEL, is the name given by M. Thenard to a black bitter principle which he supposed to be peculiar to the bile. MJVL Gmelin and Tiedemann have since called its identity in question. PICROTOXINE, is an intensely bitter poisonous vegetable principle, extracted from the seeds of the Menispermum cocculus, (Cocculus Indicus.) It crystallizes in small white needles, or columnsj dissolves in water and alcohol It does not combine with acids, but with some base^ and is not therefore of an alkaline nature, as had been at first supposed. PIGMENTS, VITRIFTABLE, belong to five different styles of work : 1. to enamel painting ; 2. to painting on metals ; 3. to painting on stoneware ; 4. to painting on porcelain ; 5. to stained glass. See VrraiFiABLE Pigments. PIGMENTS. 1. White. Alumina, white clay, heavy spar, chalk, gypsum, alabaster, and starch, and sulphate of lead. 2. Blues, Lapis lazuli blue ; azure blue ; artificial ultramarine ; Thenard's blue or cobaltic ; Giessen blue is Prussian blue dissolved in oxalic acid. Copper blue, or hydrated oxide of copper, called mountain blue ; indigo ; litmus blue ; blue (violet) from logwood by salt of tin and alkalis. 3. Green. Bremer; hydrated oxide of copper by decomposing a salt of copper with alkali ; Brunswick and mountain green are arsenites of copper, acetate of copper or verdigris ; Scheele's green ; mixtures of chrome yellow and Prussian blue ; oxide of chrome as an enamel colour ; green earth, silicate and phosphate of the protoxide of iron ; vegetable green, an extract of buckthorn berries, called also sap-green. 4. Yellow. Chrome ; yellow antimonite of lead or Naples yellow, orpiment ; hydrated oxide of iron; yellow ochre or Sienna yellow; gamboge; turmeric; yeUow wood or fustic ; quercitron ; weld ; yellow berries ; saffron ; annotto. Red pigments. Cinnabar ; basic chromate of lead ; red lead ; oxide of iron ; red lake dyes ; carmine ; cochineal ; kermes ; Brazil wood ; madder and its lake ; lac lake ; alkanet root ; sandal wood ; safilower ; umber, or earthy clay ironstone ; Cologne umber ; earthy brown coal, lamp black, and Frankfort vine black ; bone black ; sepia, obtained by drying the black fluid of the cuttle-fish, extracted by means of caustic lye ; catechu ; dyes with mordants. PIMENTO {Myrtiis pimentOf or Jamaica pepper) consists, according to Bonastre*! complicated analysis, of— Shells or capsules. Kernels. Volatile oil - 10-0 50 Soft green resin > . . 80 2-5 Fatty concrete oil - • • • 0^ 1-2 Extract containing tannin • • • 11-4 39-8 Gum --.••• 3-0 7-2 Brown matter dissolved in potash 4*0 8-0 Resinoid matter - . • • . 1-2 3-2 Extract conlainin? sugar . . • • 3*0 8-0 Gallic and malic acids .... 0-6 1-6 Vegetable fibre - - . « . 600 16-0 Ashes charged with salts .... 2*8 1-9 Moisture and loss - - - . 41 4-8 I Imported. 1850 1851 acts. 20,448 14,840 Retained for Consumption. ctots. 3564 3935 Exported. ctots. 8,510 1*7,363 Duty Receired. £ 936 loss PINCHBECK, is a modification of brass ; see that article and Coppkr. PINE-APPLE YARN and CLOTH. In Mr. Zincke's process, patented in Decem- ber, 1836, for preparing the filaments of this plant, the Bromelia ananas, the leaves being plucked, and deprived of the prickles round their edges by a cutting instrument, are then beaten upon a wooden block with a wooden mallet, till a silky-lookin? mass of fibres be obtained, which are to be freed by washing from the green fecula. The fibrous part must next be laid straight, and passed between wooden rollers. The leaves should be gathered between the time of their full maturity and the ripening of the fruit. If earlier or later, the fibres will not be so flexible, and will need to be cleared by a boil in soapy water for some hours ; after being laid straight under the pressure of a wooden grating, to prevent their becoming entangled. When well washed and dried, with occa- sional shaking out, they will now appear of a silky fineness. They may be then spun into porous rovings, in which state they are most conveniently bleached by the onlinary methods. Specimens of cambric, both bleached and unbleached, woven with these fibres, have been recently exhibited, which excited hopes of their rivalling the finest flax fabrics, but in my opinion without good reason, on account of their want of strength. PINEY TALLOW is a concrete fal obtained by boilmg with water the fruit of the Vateria indica, a tree common upon the Malabar coast. It seems to be a substance in- termediate between tallow and wax; pa. taking of the nature of stearine. It melts at 97|« F., is white or yellowish, has a spec. grav. of 0-926 ; is saponified by alkalis, and forms excellent candles. Dr. Benjamin Babington, to whom we are indebted for all our knowledge of piney tallow, found its ultimate constituents to be, 77 of carbon, 12-3 of hydrogen, and 10'7 of oxygen. PIN MANUFACTURE. (Fabrique (Pepingles, Fr. ; NadeJfabrik, Germ.) A pin is a small bit of wire, commonly brass, with a point at one end, and a spherical head at the other. In making this little article, there are no less than fourteen distinct operations. 1. Straightening the wire. The wire, as obtained from the drawing-frame, is wound about a bobbin or barrel, about 6 inches diameter, which gives it a curvature that must be removed. The straightening engine is formed by fixing 6 or 7 nails upright in a waving line on a board, so that the void space measured in a straight line between the first three nails may have exactly the thickness of the wire to be trimmed ; and that the other nails may make the wire take a certain curve line, which must vary with its thick- i»€83. The workman pulls the wire with pincers through among these nails, to the length of about 30 feet, at a running draught ; and after he cuts that off, he returns for as much more ; he can thus finish 600 fathoms in the hour. He next cuts these long pieces into engths of 3 or 4 pins. A day's work of one man amounts to 18 or 20 thousand dozen of pin-lengths. 2. Pointing is executed on two iron or steel grindilones, by two workmen one of whom roughens down, and the other finishes. Thirty or forty of the pin wires are ap- plied to the grindstone at once, arranged in one plane, between the two forefingers and thumbs of both hands, which dexterously give them a rotatory movement. 3. Cutting these wires into pin-imgths. This is done by an adjusted chisel. The inter mediate portions are handed over to the pointer. 4. Twisting of the wire for the pinJuads, These are made of a much finer wire, coiled into a compact spiral, round a wire of the size of the pins, by means of a smaU hithe constructed for the purpose. 5. Cutting the heads. Two turns are dexterously cut off for each head, by a regulated chisel. A skilful workman may turn off 12,000 in the hour. 6. Jnnealing the heads. They are put into an iron ladle, made redhot over an open fire, and then thrown mto cold water. 7. Stamping or shaping the heads. This is done by the blow of a small ram, raised to means of a pedal lever and a cord. The pin-heads are also fixed on by the same operative, who makes about 1500 pms in the hour, or from 12,000 to 15,000 per diem : exclusive of one thirteenth, which is always deducted for waste in this department, as well as ia the rest of the manufacture. Cast heads, of an alloy of tin and antimony, were introduced by patent, but never came into general use. 8. Yellowing or cUaning the pins is efi-ected by boiling them for half an hour in sonr beer, wme lees, or soluUon of tartar j after which they are washed. 386 PINS. PITCH. 387 III 4i ■ ■'> ,11 ■ 1 9. Whitening or tinning. A stratum of about 6 pounds of pins is laid in a copper pan, .hen a stratum of about 7 or 8 pounds of grain tin ; and so alternately till the vessel be filled ; a pipe being left inserted at one side, to permit the introduction of water slowly at the bottom, without deranging the contents. When the pipe is withdrawn, its space is filled up with grain tin. The vessel being now set on the fire, and the water becoming hot, its surface is sprinkled with 4 ounces of cream of tartar ; after which it is allowed to boil for an hour. The pins and tin grains are, lastly, separated by a kind of cullender. 10. Washing the pins in pure water. 11. Drying and polishing them, in a leather sack filled with coarse bran, which is agi- tated to and fro by two men. 12. Winnowing, by fanners. 13. Pricking the papers for receiving the pins. 14. Papering, or fixing them in the paper. This is done by chiklren, who acquire the habit of putting up* 36,000 per day. The pin manufacture is one of the greatest prodigies of the division of labor; it fur- nishes 12,000 articles for the sum of three shillings, which have required the united diligence of fourteen skilful operatives. The above is an outline of the mode of manufacturing pms by hand labor, but several beautiful inventions have been employed to make them entirely or in a great measure by machinery ; the consumption for home sale and export amounting to 15 millions daily, for this country alone. One of the most elaborate and apparently complete is thai for which Mr. L. W. Wright obtained a patent in May, 1824. A detailed description of it will be found in the 9th volume of Newton's London Journal. The following outline will give my readers an idea of the structure of this ingenious machine : — The rotation of a principal shaft, mounted with several cams, gives motion to various sliders, levers, and wheels, which work the diflTerent parts. A slider pushes pincers for- wards, which draw wire from a reel, at every rotation of the shaft, and advance such a length of wire as will produce one pin. A die cuts off the said length of wire by the descent of its upper chap ; the chap then opens a carrier, which takes the pin to the pointing apparatus. Here it is received by a holder, which turns round, while a bevel- edged file-wheel rapidly revolves, and tapers the end of the wire to a point. The pin is now conducted by a second carrier to a finer file-wheel, in order to finish the point by u $econd grinding. A third carrier then transfers the pin to the first heading die, and by llie advance of a steel punch, the end of the pin wire is forced into a recess, whereby the head is partially swelled out. A fourth carrier removes the pin to a second die, where the heading is perfected. When the heading-bar retires, a forked lever draws the finished pin from the die, and drops it into a receptacle below. I believe the chief objection to the raising of the heads by strong mechanical com- pression upon the pins, is the necessity of softening the wire previously ; wherel)y the pins thus made, however beautiful to the eye, are deficient in that stiffness which is so essential to their employment in many operations of the toilet. Edelsten, and Williams, New Hall Works, Birmingham, Manufacturers. Pins, the heads and shafts being formed of one solid piece of metal, in order to render the head im- moveable and smooth in use, made by improved machinery. Model dies to show the formation of the head. Elastic hair-pins. Specimens of iron wire in various sizes. In pin making the wire is brass (a compound of copper and zinc) : it is reduced by the ordinary process of wire drawing to the requisite thickness: in this process it is necessa- rily curved. To remove this it is re-wound, and pulled through between a number of pina arranged at the draw or straightening bench ; it is then cut into convenient lengths for removal, and finally reduced to just such a length as will make two pins. The pointing is done upon steel mills (revolving wheels), the circumference of whicn is cut with teeth, the one fine, the other coarse. Thirty or forty lengths are packed up at once, and, as in needle-making, the cast of hand given by the workman makes them revolve, and the whole are pointed at once ; the same operation is performed with the other end. The process of heading is next performed as follows : a number of the pointed wires now cut in two, are placed in the feeder of the machine ; one drops, is firmly seized, and, by means of a pair of dies, a portion of the metal is forced up into a small bulb ; by a beautifully simple and automatic arrangement, it is passed into another, when a small horizontal hammer gives it a sharp tap, which completes the head. The white colour is produced by boiling in a solution of cream of tartar and tin. They are then dried, and passed into the hands of the wrappers-up. The preparation or marking of the paper is peculiar, and is done by means of a moulded piece of wood, the moulds corre- sponding to those portions which represent the small folds of paper through which the pins are passed, and thereby held. The pins are then taken to the paperers, who are each seated in front of a bench, to which is attached a horizontally hinged piece of iron the edge of which is notched with a corresponding number of marks to the number of pins to be struck ; the small catch which holds together the two parts of the iron is released, the paper introduced, and a pin inserted at every mark ; the paper is then re- leased, and the task of examination follows, which is the work of a moment. The paper of pins is held so that the light strikes upon it : those defective are immediately detected by the shade, are taken ou^ and others substituted in their stead. An ancient edict of Henry VIII., held that, " no one should sell any pins but such as were double-headed, and the heads soldered fast on.** Pins, Improved. — The selection and preparation of the wire. — ^The iron or steel wire employed should be very round, and, to protect it from rust, it should at the last drawing be lubricated by means of a sponge saturated with oil, placed between the draw-plate and reel. In all the subsequent stages of the manufacture, care should also be taken to preserve the pins from oxidation by keeping them well oiled and greased. The cleansing and polishing. — The wire being cut into pins, and these headed and pointed, all according to the usual methods, the pins are thrown into a revolving cylinder of wood containing a bath of soap and water in a hot state. It is of the capacity of about 9^ gallons, but should not contain more than about 1^ gallons of water, with about 2 ounces of soap dissolved therein, as this quantity will be suflScient for the treat- ment of about 13^ lbs. weight of pins at a time. The cylinder, when thus charged, is made to revolve for about a quarter of an hour ; at the expiration of which time the pins are found free from' the oil with which they were previously coated, and also very much smoothed and polished by their rubbing one against the other. The drying. The pins are next dried by transferring them to another cylinder par- tially filled with well dried sawdust (preferring for the purpose the sawdust of poplar wood), and causing this cylinder to revolve for about ten minutes ; or, instead of employing a cylinder of this description, the pins may be thrown into a bag or bags partially tilled with the sawdust, and the requisite friction produced by swinging or rolling these bags about for the same length of time. The copper coating bath or mixture. — Into a glass or stone vase, tue inventor puts about 1^ gallons of soft water, seven -tenths of a pound of sulphuric acid, six-one hun- dredth lb. of salt of tin, eight-one hundredth lb. of crystallized sulphate of zinc, and 108 grs. of pure sulphate of copper, and leaves this mixture to work for about 24 hours, so that the salts and sulphates may be properly dissolved. This is found to be, on the whole, the mixture best adapted for the purpose in view ; but most of the ingredients mentioned may have others substituted for them, as, for example, any other acid or substance pro- ducing like effects ma}^ be used instead of the sulphuric acid, or the sulphate of tin may be substituted for the salt of tin. The copper coating process. — ^The mixture, prepared as last directed, is introduced into another revolving cylinder, and pins about 13^ lbs. weight are thrown into the midst of it The cylinder is then caused to revolve for about half an hour, which serves at once to remove any verdigris from the pins to impart a high polish to them, and to give a beginning to the copper coating process. At the end of the half hour or thereabouts 232 grs. of crystallized sulphate of copper in coarse powder, and 150 grs. of crystallized sulphate of zinc, previously dissolved in soft water, are added to the mixture in the cylinder, and the whole again agitated for about a quarter of an hour. The pins are by this operation not only completely coated, but acquire a very considerable degree of polish. The copper liquors being drawn off, the pins are washed with cold water in the rotating cylinder, and afterwards in a tub with soap and water out of contact with air, where they are well shaken. The contents of the tub are then emptied into a wooden strainer, having a perforated bottom of tin plate iron. The pins are finally dried by agitation with dry sawdust The tinning and blanching are performed by laying the pins upon plates of very thin tin placed one above another, in a tinned copper boiler containing a solution of about 4 two-fifth lbs. of crude tartar or cream of tartar, in about 22 galls, of water, and then setting the whole to boil for about 12 hours. The tartar , solution should be prepared at least 24 hours previously. A little more cream of tartar improves the brilliancy of the pins. PIPKRINE is a crystalline principle extracted from black pepper by means of alcohol. It is colorless, has hardly any taste, fuses at 212° F. ; is insoluble in water, but soluble in acetic acid, ether, and most readily in alcohol. PITCH, MINERAL, is the same as Bitumen and Asphalt. PITCH of vmd-tar (Poix, Fr.; Pech, Germ.) is obtained by boiling tar in an open iron pot, or in a still, till the volatile matters be driven off. Pitch contains pyrolismeous resin, along with colophany (common rosin), but its principal ingredient is the former, called by Berzelius pyretine. It is brittle in the cold, but softens and becomes ducti e I i !i ; » ■ \ I 1 i i 1 ! • M\l i . i ■■a ■t- , , i'- , f kl -. t. 388 PITCOAL. with heat. It melts in boiling water, and dissc:ve8 in alcohol and oU. of turpentine, at well as in carbonated or caustic alkaline leys. For Pyretine, see the mode of preparing it from birch wood, for the purpose of preparing Russia Leather. PITCOAL. (HouilUj Fr. ; SUinkohky Germ.) This is by far the most valuable of mineral treasures, and the one which, at least in Great Britain, makes all the others available to the use and comfort of man. Hence it has been searched after with unre- mitting diligence, and worked with all the lights of science, and the resources of art. The Brora coal-field in Sutherlandshire is the most remarkable example in this, or in perhaps any country hitherto investigated, of a pseudo coal basin amon? the deeper secondary strata, but above the new sandstone or red marl formation. The Rev. Dr. Buckland and Mr. C. Lyell, after visiting it in 1824, had expressed an opinion that the strata there were wholly unconnected with the proper coal formation below the new red sandstone, and were in fact the equivalent of the oolitic series ; an opinion fully confirmed by the subsequent researches of Mr. Murchison. {Geol. Trans, for 1827, p. 293.) The Brora coal-field forms a part of those secondary deposites which range along the south- east coast of Sutherlandshire, occupying a narrow tract of about twenty miles in length, and three in its greatest breadth. One stratum of the Brora coal-pit is a coal-shale, composed of a reed-like striated plant of the natural order Equiselum, which seems to have contributed largely towards the formation of that variety of coal. From this coal-shale, tlie next transition upwards is into a purer bituminous substance approachir c im The purer part of the Brora coal resembles common pitcoal; but its powder has the red ferruginous tinge of pulverized lignites. It may be considered one of the last links between lignite and true coal, approaching very nearly in character to jet, though less tenacious than that mineral ; and, when burnt, exhaling but slightly the vegetable odor so peculiar to all imperfectly bituminized substances. The fossil remains of shells and plants prove the Brora coal to be analogous to that of the eastern moorlands of York- shire, although the extraordinary thickness of the former, compared with any similar deposite of the latter (which never exceeds from 12 to 17 inches), might have formerly led to the belief that it was a detached and anomalous deposite of true coal, rather than a lignite of any of the formations above the new red sandstone : such misconception might more easily arise in the infancy of geology, when the strata were not identified by their fossil organic remains. On the coast of Yorkshire the strata of this pseudo coal formation appear in the follow- ing descending order, from Filey Bay to Whitby. 1. Coral-rag. 2. Calcareous grit. 3. Shale, with fossils of the Oxford clay. 4. Kelloway rock (swelling out into an impor- tant ar-naceous formation). 5. Cornbrash. 6. Coaly grit of Smith. 7. Pierstone (ac- cording to Mr. Smith, t\ie equivalent of the great oolite). 8. Sandstone and shale, with peculiar plants and various seams of coal. 9. A bed with fossils of the inferior oolite. 10. Mari-stone ? 11. Alum-shale or lias. All the above strata are identified by abundant organic remains. In the oolitic series, therefore, where the several strata are developed in conformity with the more ordinary type of these formations, we may venture to predict with certainty, that no carboniferous deposites of any great value will ever be discovered, at all events in Great Britain. A want of such knowledge has induced many persons to make trials for coal in beds subordinate to the English oolites, and even superior to them, m places where the type of formation did not offer the least warrant for such attempts. . The third great class of terrestrial strata, is the proper coal-measures, called the carboniferous rocks, our leading object here, and to which we shall presently return. The transition rocks which lie beneath the coal-measures, and above the primi- tive rocks, or are anterior to the carboniferous order, and posterior to the primitive, contain a peculiar kind of coal, called anthracite or stone-coal, approaching closely in its nature to carbon. It is chiefly in the transition clay-slate that the anthracite occurs in considerable masses. There is one in the transition slate of the little Saint Bernard, near the village of la Thuile (in the Alps). It is 100 feet long, and 2 or 3 yards thick. PITCOAL. 389 The coal bums with difficulty, and is used only for burning lime. There are seveml of the same kind in that country, which extend down the reverse slope of the mountains looking to Savoy. The slate enclosing them presents vegetable impressions of reeds or analogous plants. To the transition clay-slate we must likewise refer the beds of anthra- cite that M. Hericart de Thury observed at very great heights in the Alps of Dauphiny, in a formation of schist and gray-wacke with vegetable impressions, which reposes direct- ly on the primitive rocks. The great carboniferous formation may be subdivided into four orders of rocks : 1. the coal-measures, including their manifold alternations of coal-beds, sandstones, and shales ; 2. the millstone grit and shale towards the bottom of the coal measures ; 3. the carbon- iferous limestone, which projecting to considerable heights above the outcrop of the coal and grit, acquires the title of mountain limestone ; 4. the old red sandstone, or connect- ing link with the transition and primary rock basin in which the coal system lies. The coal-fields of England, from geographical position, naturally fall under the follow- ing arrangement :—l. The great northern district; including all the coal-fields north of Trent. 2. The central district ; including Leicester, Warwick, Stafford, and Shrop- shire. 3. The toestem district ; subdivided into north-western, including North Wales, and the south-western, including South Wales, Gloucester, and Somersetshire. There are three principal coal-basins in Scotland: 1. that of Ayrshire; 2. that ot Clydesdale ; and 3. that of the valley of the Forth, which runs into the second in the line of the Union Canal. If two lines be drawn, one from Saint Andrews on the north- cast coast, to Kilpatrick on the Clyde, and another from Aberlady, in Haddingtohshire, to a point a few miles south of Kirkoswald in Ayrshire, they will include between them the whole space where pitcoal has been discovered and worked in Scotland. The great coal-series consists of a regular alternation of mineral strata deposited in a great concavity or basin, the sides and bottom of which are composed of transition rocks. This arrangement will be clearly understood by inspecting fig. 1051 which represents a section of the coal-field south of Malmsbury. Mendip hills. Dundry hill. Wick rocks. Fog hill, N. of Lansdownc 1, I, old red sandstone; 2, mountain limestone; 3, millstone grit; 4, 4, coal seams; 6, Pennant, or coarse sandstone ; 6, new red sandstone, or red marl ; 7, 7, lias ; 8, 8, in- ferior oolite ; 9, great oolite ; 10, cornbrash and Forest marble. No. 1, or the old red sandstone, may therefore be regarded as the characteristic lining of the coal basins ; but this sandstone rests on transition limestone, and this limestone on gray-wacke. This methodical distribution of the carboniferous series is well exemplified in the coal-basin of the Forest of Dean in the south-west of England, and has been accu- rately described by Mr. Mushet. The gray-wacke consists of highly inclined beds of slaty micaceous sandstone, which on the one hand alternates with and passes into a coarse breccia, having grains as large as peas ; on the other, into a soft argillaceous slate. The gray-wacke stands bare on the north-eastern border of the Forest, near the southern extremity of the chain of transition limestone, which extends from Stoke Edith, near Hereford, to Flaxley on the Severn. It is traversed by a defile, through which the road from Gloucester to Ross winds. The abruptness of this pass gives it a wild and mountainous character, and affords the best op portunity of examining the varieties of the rock. The Transition limestone consists in its lower beds of fine-grained, tender, exuemely argillaceous slate, known in the district by the name of water-stone, in consequence of the wet soil that is found wherever it appears at the surface. Calcareous matter is inter- spersed in it but sparingly. Its upper beds consist of shale altematinsr with extensive beds of stratified limestone. The lowest of the calcareous strata are thin, and alternate with shale. On these repose thicker strata of more compact limestone, often of a dull blue color. The beds are often dolomitic, which is indicated by straw yellow color, or dark pink color, and by the sandy or glimmering aspect of the rock. The old red sandstone, whose limits are so restricted m other parts of England, here I 390 PITCOAL. PITCOAL. 391 if m ; occupies an extensive area. The space which it covers, its great thickness, its high in- clmation the abrupt character of the surface over which it prevails, and the consequent display of Its strata in many natural sections, present in this district advantages for studying the formation, which are not to be met with elsewhere in South Britain. In the neigh- borhood of Mitchel Dean, the total thickness of this formation, interposed conformably between the transition and mountain limestone, is from 600 to 800 fathoms. The old red sandstone is characterized in its upper portion by the presence of silicious conglomerate, containing sihcious pebbles, which is applied extensively to the fabrication of millstones near Monmouth, and on the banks of the Wye. This sandstone encircles the Forest with a ring of very elevated ground, whose long and lofty ridges on the eastern frontier over- hang the valley of the Severn. The maujitain limestone, or carboniferous, is distinguished from transitipn limestone rather by its position than by any very wide difference in its general character or organic remains. According to the measurements of Mr. Mushet, the total thickness of the mountain limestone is about 120 fathoms. The zone of limestone belonging to this coal-basin, is from a furlong to a mile in breadth on the surface of the r-^und, according as the dip of the strata is more or less rapid. The angle of dip on 'th^ northern and western border is often no more than 10°, but on the eastern it frequently amounts to 80°. The calcareous zone that defines the outer circle of the basin, surfers only one short interruption, scarcely three miles in length, where in consequence of a fault the limestone disappears, and the coal-measures are seen in contact with the old red sandstone. Coal meawm.— Their aggregate thickness amounts, according to Mr. Mushet, to about 500 fathoms. 1. The lowest beds, which repose on the mountain limestone, are about 40 fathoms thick, and consist here, as in the Bristol coal- basin, of a red silicious grit alter- nating with conglomerate, used for millstones ; and with clay, occasionally used'fo/ochre 2. These beds are succeeded by a series about 120 fathoms thick, in which a gray griti stone predominates, alternating in the lower part with shale, and containing 6 seams of coal. The grits are of a fissile character, and are quarried extensively for flag-stone ashlers^ and fire-stone. 3. A bed of grit, 25 fathoms thick, quarried for hearth-stone' separates the preceding series from the followins, or the 4th, which is about 115 fathoms thick, and consists of from 12 to 14 seams of coal alternating with shale. 5. To this succeeds a straw-colored sandstone, nearly 100 fathoms thick, forming a high xii^e in the interior of the basin. It contains several thin seams of coal, from 6 to \6 inches In thick- ness. 6. On this reposes a series of about 12 fathoms thick, consisting of 3 seams of coal alternating with shale. 7. This is covered with alternate beds of grit and shale whose aggregate thickness is about 100 fathoms, occupying a tract in the centre of the basin about 4 miles long, and 2 miles broad. The sandstone No. 5 is probably the equiva- lent of the Pennant in the preceding figure. The floor, or pavement, immediately under the coal beds is, almost without exception a grayish slate-clay, which, when made into bricks, strongly resists the fire. This fire- clay varies in thickness from a fraction of an inch to several fathoms. Clay-ironstone is often disseminated through the shale. The most complete and simplest form of a coal-field is the entire basin-shape which we find in some instances without a dislocation. A beautiful example of this is to be seen at Blairengone, in the county of Perth, immediately adjoining the western boundary of Clackmannanshire, as represented in fig. 1052, where the outer elliptical lino, marked 1055 East B I l"*^ A West EastB A Weal 1056 1067 A, B, c, D, represents the crop, outburst, or basset edge of the lower coal, and the inner elliptical Une represents the crop or basset edge of the superior coal. f»g.l053is the .ongitudinal section of the line A b ; and yig. 1054 the transverse section of the line c d AJl the accompanying coal strata partake of the same form and parallelism. These basins are generally elliptical, sometimes nearly circular, but are often very eccentric, being much greater in length than in breadth ; and frequently one side of the basin on the short diameter has a much greater dip than the other, which circumstance throws the trough or lower part of the basin concavity much nearer to the one side than to the other. From this view of one entire basin, it is evident that the dip of the coal strata belonging to it runs in opposite directions, on the opposite sides, and that all the strata regularly crop out, and meet the alluvial cover in every point of the circumferential space, like the edges of a nest of common basins. The waving line marks the river Devon. It is from this basin shape that all the other coal-fields are formed, which are segments of a basin produced by slips, dikes, or dislocations of the strata. If the coals (%. 1062) were dislocated by two slips 6 c and d e, the slip 6 c throwing the strata down to the east, and the slip d e throwing them as much up in the same direction, the outcrops of the coals would be found in the form represented in Jig, 1065 of which^g.l056LS the section in the line A B, and yig. 800 the section in the line c d. The chief difficulty in exploring a country in search of coal, or one where coal-fields are known to exist, arises from the great thickness of alluvial and other cover, which completely hides the outcrop or basset edge of the strata, called by miners the rock-head ; as also the fissures, dikes, and dislocations of the strata, which so entirely change the structure and bearings of coal-fields, and cause often great loss to the mining adventurer. The alluvial cover on the other hand is beneficial, by protecting the seams of the strata from the superficial waters and rains, which would be apt to drown them, if they were naked. In all these figures of coal-basins, the letter a indicates coal. The absolute shape of the coal-fields in Great Britain has been ascertained with sur- prising precision. To whatever depth a coal-mine is drained of its water, from that depth it is worked, up to the rise of the water-level line, and each miner continues to ad- vance his room or working-place, till his seam of coal meets the alluvial cover of the outcrop, or is cut off by a dislocation of the strata. In this way the miner travels in s«c- cession over every point of his field, and can portray its basin-shape most minutely, l^'tg. 1058 represents a horizontal plan of the Clackmannanshire coal-field, as if the 1058 strata at the outcrop all around were denuded c:^^i'y£2 of the alluvial cover. Only two of the con- centric beds, or of their edges a, a, are repre sented, to avoid perplexity. It is to be re- membered, however, that all the series of at- tendant strata lie parallel to the above lines. This plan shows the Ochill mountains, with the north coal-fields, of an oblong elliptical shape, jWestthe side of the basin next the mountains being precipitous, as if upheaved by the eruptive ^'•** ^^'-^^ S^ ^^""^^^''^N, slip. trap-rocks; while JKifefefe^^;- ^? ^?; west distance edges of the from the the south, the east, and the basin shelve out at a great lower part of the concavity or trough, as miners call it. Thus the alternate beds of coal, shale, and sandstone, all nearly concentric in the north coal-field, dip inwards from all sides towards the central area of the trough. The middle coal-field of this district, however, which is formed by the great north slip, is merely the segment of an elliptical basin, where the strata dip in every direction to the middle of the axis marked with the letter x ; being the deepest part of the segment. The south coal-field, formed by the great south slip, is likewise the segment of another elliptical basin, similar in all respects to the mid- dle coal-field. Beyond the outcrop of the coals and subordinate strata of the south coal- fields, the counter dip of the strata takes place, producing the mantle-shaped form ; whence the coal strata in the Dunmore field, in Stirlingshire, lie in a direction contrary to those of the south coal-field of Clackmannanshire, o, are the Ochill mountains. Fig. 1059 is intended to represent an extensive district of country, containing a great coal-basin, divided into numerous subordinate coal-fields by these dislocations. The lines marked 6 are slips, or faults ; the broad lines marked c denote dikes ; the former dislocate the strata, and change their level, while dikes disjoin the strata with a wall, but do not in general affect their elevation. The two parallel lines marked a, represent two seams of coal, variously heaved up and down by the faults ; whereas the dikes are seen to pass through the strata without altering their relative position. In this manner, partial coal- ields are distributed over a wide area of country, in every direction. The only exception to this general form of the coal-fidds in Great Britain, is the in- 392 PITCOAL. but a partial occurrence, or a deviat[nn J^ ^^^^^f »^? ^oal-fields, this convex form U, ^ -^^ hill, close to the town of Dudley. i, 1, are Lmestone strata; 2, 2, are cool. Through this hill, canals have been cut, Jor working the immense beds of carboniferous limestone. These occui in the lower series of the strata of the coal-field, and therefore at a dis- tance of many miles from the Castle- hill, beyond the outcrop of all the workable coals in the prqper basin- shaped part of the field; but by this apparently inverted basin-form, these imestone beds are elevated far above the level of the general surface of the country, and consequer Jy above the eyel of all the coals. We must regard this seeming inversion as resulting from the approximation of two coal-basins, sep- arated by the basset edges of their moun- tain jimestone repository. Fig. 1061 is a vertical section of the Dudley c(»l-basin, the nppcr coal-bed nr on r ^^^ }^^ astonishing thickness 01 SO feet ; and this mass extends 7 miles in length, and 4 in breadth. Coal-seams a or 6 feet thick, are called Miw in that district. 1^1^.1062 18 a very interesting section of the mam coal-basin of Clackman- nanshire, as given by Mr. Bald in the ^ Wernerian Society's Memoirs, vol. iii. ordinate coal-fields, formed by two ereat^lluul^ n7%T '!• ^'""^^J" i"*° ^^'^^ ^"^ independently of these fractures arrrS/tL J , ^»5^°«^tion8 of the strata; but which dislocates the coal and the narallpl -^trui Jtr!*l 'P*» of I9*?n f^^i K« ™k- u 11 1^ Pa'aiiei strata to the enormous extent and coal-field resume their course and H:„ ™ i ? f ' ""* '"■■» ning through a longer range than ^rher oMh?„",^''^/"'''''*;^^ """- miners. coal-seams thus upheaved, are called edge-metals by the 1062 ' PITCOAL. 39a In this remarkable coal-field, which has been accurately explored by pitting and boring to the depth of 703 feet, there are no fewer than 142 beds, or distinct strata ol coal shale, and sandstone, &c., variously alternating, an idea of which may be had 1063 bv inspecting jig- 1063 Among these are 24 beds of coal, which would con- sl'iiute an aggregate thickness of 59 feet 4 inches ; the thinnest seam ol coal being 2 inches, and the thickest 9 feet. The strata of this section contain numerous varieties of sandstone, slate-cay, bituminous shale, indurated clay, or fire-clay, and clay ironstone. Neither trap-rock nor limestone is found in con- nexion with the workable coals ; but an immense bed of greenstone, named Abbey Craig, occurs in the western boundary of Clackmannanshire, under which lie regular strata of slate-clay, sandstone, thin beds of limestone, and large sphe- roidal masses of clay ironstone, with a mixture of lime. « With regard to slips in coal-fields," says Mr. Bald, « we find that there is a general law ''connected with them as to the position of the dislocated strata, which is this :— W^hen a slip is met with in the course of working the mines — if when looking to it, the vertical line of the slip or fissure, it forms an acute angle with the line of the pavement upon which the observer stands, we are certain that the strata are dislocated downwards upon the other side of the fissure. On the contrary, if the angle formed by the two lines above mentioned is obtuse, we are certain 'that the strata are dislocated or thrown upwards upon the other side of the fissure. When the angle is 90% or a right angle, it is altogether uncertain whether the dislocation throws up or down on the opposite side of the slip. When dikes intercept the strata, the^ generally only separate the strata the width of the dike, without any dislocation, either up or down ; so that if a coal is intercepted by a dike, it is found again by running a mine directly forward, corresponding to the angle or inclination of the coal with the horizon. — Wernerian Society's Memoirs, vol. iii. p. 133.* The Johnstone coal-field, in Renfrewshire, is both singular and interesting. The upper stratum of rock is a mass of compact greenstone or trap, above 100 feet in thickness, not at all in a conformable position with the coal strata, but overlying; next there are a few fathoms of soft sandstone and slate-clay, alter- nating, and uncommonly soft Beneath these beds, there are no fewer than ten seam^ of coal, lying on each other, with a few divisions of dark indurated clay. These coal-seams have an aggregate thickness of no less than 100 feet ; a mass of combustible matter, in the form of coal, unparalleled for its accumulation in so narrow a space. The greater part of this field contains only 5 beds of coal ; but at the place where the section shown in^g.l064i8taken, these five coals seem to have been overlapped or made to slide over each other by violence. 1 his struc- ture is represented in fig- 1065 which is a section of the Quarrellon coal m he Johnstone field, showing the overlapped coal and the double coal, with the thick bed of greenstone, overlying the coal-field. 1065 a. Alluvial cover. «• Position of greenstone, not ascertained. 6.' Bed of trap or greenstone. /. Strata in which no coals have been found. / Alternating coal strata. g. The overlapped coal. d. Coal-seams. h. The double coal. Before proceeding to examine the modes of working coal, I shall introduce here a de- scription of the two principal species of this mineral. 1. Cubical coal.— li is black, shining, compact, moderately hard, but easily frangible. When extracted in the mine, it comes out in rectangular masses, of which the smaller frac'ments are cubical. The lamellae (reed of the coal) are always parallel to the bed or plane on which the coal rests ; a fact which holds generally with this substance. There are two varieties of cubical coal ; the open-biimivg and the caking. The latter, however small iis fragments may be, is quite available for fuel, in consequence of its agglutinating into a mass at a moderate heat, by the abundance of its bitumen. This kind is the true smithy or forge-coal, because it readily forms itself into a vault round the blast of the bellows, which serves for a cupola in concentrating the heat on objects thrust into the The open-burning cubical coals are known by several local names; the rough coal or ♦ Thi« paper does honor to its author, the eminent coal-viewer of Scotland. Vol. II. 3 E >' r< iiHil 394 PITCOAL. Siil^I?.'^!!?^ "" '°i^ ?TVu " ""'"' "'«'' ■"»'' •» •'"'J ""d the cherry coal, from « ■.iHri^ w ""^,'""'=^. >■«? spontaneously burn ; whereas the caking coals such "c gravity taSrlX^'",*?' "'""'^ •" "" '"'^'""''"'^ '»''"' - "'^ 5""- "^ W *t^;u1[rfJ„^^r.C^i;\t^^^^^^^^^^ resists the cross fracture, which is conchoidal. S|«cific |rav y from h26 to'^-40 ij cltn'^'^rl^^tl Z '"S«,1"=>''i;'"'Sular sharp-edgi masses It Zfns tilhou" caKmg, produces much flame and smoke, unless judiciously supplied with air and leaves £?2e"'." Ls rft mLke" '"'" •"■ f "^ "f r- " '' '"« best'fllell; dSr es and al large grates, as it makes an open fire, and does not clog up the bars with »la«v scoria LSofla^bon' 70-9 "il^" """T? ^''' '" ""^ ^'^'^' gravi7y'of°l^^,3^ consist 01 — carbon, 70-9 ; hydrogen, 4'3 ; oxygen, 24-8. 3. Camiel coal.— Color between velvet and grayish-black : lustre rcMnous- fracture even; fragments trapezoidal ; hard as splint coal ; spec. grav;i.2^To As Tn\vo^^^^^^ It IS detac ed m four-sided columnar masses, oftei b'reaks coichoidll, lile pit^knilS wh^nc'ftfname rn"^'' " 'J^^k' white projective flame, like thi wick'of a' Sle ^ a bed 4 feerthiJ Tn^V "'''•' ^^"^^^f^^ V^^ "^^^'^^'^ °^ ^igan, in Lancashire in a bed 4 teet thick ; and there is a good deal of it in the Clydesdale wal-field of which Lrdirsoil' hrfiLT" ''.h' " r'^'- '' ^^^^^^^^ -^^ '^"^^ du^t "n the mLTanS hardly soil^ the fingers wuh carbonaceous matter. Cannel coal from Woodhall near nrTJ^^'hf'nt ^'^Z' ^'^^' "«"^^^^^ ^>' "^^ ^»^^>«i« of-carbon, 72-22? hyZ^en 3^3 S in the ScoT^L' " '"'' r^' ^'"^"^ ?•? '"^ ''^ ^''^'^ This coal'has beek ?ound ti anord, m the Scotch gas-works, a very rich-burning gas. The azote is there converted '4 'Gw'Lf'Th' ' considerable quantity is disUlled over inL th^ tar-pTt '"^ likt^farof temne7J.;L'rr't ^'' ^" ^'""-.^^^^^ ^"^«''' ^'^^ ^" occasional iridiscence, liKe that ot tempered sleel; lustre in general splendent, shining, and imierfect metallic- does not soil ; easily frangible ; fracture flat conchoidal ; fra<^meSts sha r^edoS It burns s^ I pScTsriT'^d "'^"^^- 7 -^p*^---; a'nTri:trafhite.ts asa. It produces no soot, and seems, indeed, to be merely carbon or coal denrived of iuVnt J^^m ^on^'acTwTw^"^ and converted into coke by L^errakean^clS o^^^^^^^^^ quenl > Horn contact with whm-dikes. Glance coal abounds in Ireland under the name lo^e'^a^r^ale^'^tt'tt " l'^'"'' '^'"'^ '^^^^^ ^^^^ "^ bur^fwithout flame or smoKe ana in Wales, it is the malting or stone coal. It contains from 90 to 97 ner cent puruLs"- '""'''" '''''''' ^''"^ '-' '' '-' ' ^"^--^"^ ^'^'^ '^- prop^rtl of Sy iS!: «, dffficulf fnf tti^mi^lT^iT ^'"'^^ ^'\^«-l-fields, which render the search for coal ? nik^h o c/ • S" ? laborious and uncertain, are the following :— ^y.^ l\u ^' ?'r ?r ^«"^'^- 3. Hitches. 4. Troubles, ^ The first three infer dislocation of the strata ; the fourth changes in the bed of coal itself Les extenYnrLt'^'^^'^T^ ""^^f' "'^^'^ ''^'^'^ -" '^' ^e^sLTcolv^t"^' run soLtimL in diffprLT r ^^^ «^ ^^^ji"? through coal-fields for many miles, but eTe^^rsr^^Tch'th" ' ^i?f 10^ '' ^ ^^^^ '"'"' ^""-^^"^ in various d^rS^^^^^^^ even crossu^ each other. Fig. 1066 represents a ground plan of ^ coal-field, intersected H F "" ~ With greenstone dikes. A b and c fc are two dikes standing parallel to each other ; E F and G H are cross or oblique dikes, which divide both the coal strata and the primary dikes a b and c d. 2. Slips or faults run in straight lines through coal-measures, and at every angle of incidence to each other. Fig. 1067 represents a ground plan of a coal-field, with two slips a b and c d in the line of bearing of the planes of the strata, which throw them down to A the outcrop. This is the simplest form ^ of a slip. Fig. 1068 exhibits part of a ^ coal-field intersected with slips, like a cracked sheet of ice. Here a b is a J . dike; while the narrow lines show :rrs^v: t^. i^it ? ^- ^ ^.^ i»^"tee a Ji/cAel ' ' ' "* '^^ ^'""^^ ^* "" ^^^«t^ ^°"^ smaU partial slips called PITCOAL. 395 The effects of slips and dikes on the coal strata appear more prominently wheti viewed in a vertical section, than in a ground plan, where they seem to be merely waUs, veins, and lines of demarcation. Fig. 1069 is a vertical section of a coal-field, from dip crop. 1068 AC 1069 rise F D B dip. to rise, showing three strata of coal a, 6, c. a b represents a dike at right angles to thfc plane of the coal-beds. This rectangular wall merely separates the coal-measures, affecting their line of rise ; but further to the rise, the oblique dike c d interrupts the coals a, /», c, and not only disjoins them, but thro\rs them and their concomitant strata greatly lower down ; but still, with this depression, the strata retain their parallelism and general slope. Nearer to the outcrop, another dike e, f, interrupts the coals a, 6, c, not merely breaking the continuity of the planes, but throwing them moderately up, so as to produce a steeper inclination, as shown in the figure. It sometimes happens that the coals in the compartment h, betwixt the dikes c and e, may lie nearly horizontal, and the effect of the dike e, f, is then to throw out the coals altogether, leaving no vestige of them in the compartment k. "Such," says Mr. Bald, from whom these illustrations are borrowed, « are the most prominent changes in the strata, as to their line of direction, produced by dikes ; but of these changes there are various modifica- tions." The effect of slips on the strata is also represented in the vertical section, /g. 1070 where a, 6, c are coals with their associated strata. A, b, is an intersecting slip, which throws all 1070 the coals of the first com- partment much lower, as is observable in the second, No. 2 ; and from the amount of the slip, it brings in other coal-seams, marked 1, 2, 3, not in the compartment No. 1. c, D, is a slip pro- ducing a similar result, bul not of the same magnitude. E, F represents a slip across Y D ^ the strata, reverse in direc- the former ; the effect of which is to throw up the coals, as shown in the area Such a slip occasionally brings into play seams seated under those marked a, h, c, .••y.,>-'<\»> -^,,,,^f,. tiUUH tlon to No. 4. 1071 l^ yf""t fU(Cf^t*"' ""'TMllif'" I ■ LM-ar i iii i iM i as seen at 4, 5, 6 ; and it may happen that the coal marked 4 lies in the pro- longation of a well-known seam, as c, in the compartment No. 3, when the case becomes puzzling to the miner. In addition to the above varieties, a number of slips or hitches are often seen near one another, as in the area marked No. 5, where the individual displace- ments are inconsiderable, but the ag- gregate dislocation may be great, in reference to the seams of the 6th compart- ment. The results of dikes and slips on a hori- zontal portion of a field are exemplified in fig. 1071. Where the coal-measures are horizontal, and the faults run at a greater angle than 45° to the line of bearing, they are termed dip and rise faults, as a b, c d, E F. Coal-viewers or engineers regard the dislocations now described as being sub- ject in one respect to a general law, which may be thus explained : — Let fig. 1072 396 PITCOAL. PITCOAL. 397 f be a portion of a coal-measure ; a, being the pavement and b the roof of the coal-seam If, m pursuing the stratum at c, a dike d occurs, standing at rH^t ancles wth X' pavement they conclude that the dike is merely a Wut'otwaU teVwee^^^^^^^^^ its own thickness, leaving the coal-seam underanged on either side but if a dike . forms, as at e, an obtuse angle with the pavement,^hey conclude that' the d ke is not a simple partition between the strata, but has thrown up the several seams into he nrP dicament shown at g Finally, should a dike h make at i aTacuteTngleUth t^^^^^ Srof K.'' ""''"'' '"^^ '"' "^^ '^^ '^^^^"'^ ^^-'^ the"cormeasu?esTnlo tt The same important law holds with slips, as I formerly stated ; only when thev form Dikes and faults are denominated upthrow or downthrow accordin«r tn th» ,./.«:.:^« djke hkew.se towards the rise. Oa the other hand, when theX« are X wUh by Z miner m working from the rise to the dip, the names of the above dikes would ™e reveLid* c«;e7the''thrckT.«I;?',hf *''.'"■* """" and partial dips, where the dislocation does not S»„ ^ m-,'^' °^ ""* '=»,a'-s<«m ; and they are correctly enough called Uev, bv the Buner. f .g. I073represen^ts rte operaUon of the kitcKe, a, b,*;, d, i, r^X onThe LIS! measures. Though observed in one or two seams of a field, they may not appear in the rest, as is the case with dikes and faults. 4. Troubles in coal-fields are of various kinds. 1. Irregular layers of saneU stoftie, appearing in the middle of the coal-seam, and gradually increasing in thickness till they separate the coal into two dis- tinct seams, too thin to continue workable. 2. Nipsy occasioned by the "^radual approximation of the roof 1073 and pavemeHOanSt a vestige of coal is left between th;m rTheTorr shj diskppe':? S^mre."'.LT.Vr'- '''>•.• 1"*""'' ^^U represent this accMent, wWch 'SK 5 'ir^J ' ">=fifst being a vertical, and the second a horizontal view. , Ji J ? • "!} • J' '«,™''"«s «>e ™l>t>ish of an old waste, being a confused heap of ^tLtheCde ™,T' i"'"''^'"' '=",'"^=" •=•«"• ^ ^°" "'^' '• «»" frequenlly te'dS^ with the spade. This shattering is analogous to that observed occasionally in the flint noduks of the chalk formation, and seems like the eifect of some electric tremor of thi J^J^?:?}^^ '"J' "??' '" "">' tonntry, its concomitant rocks ought to be looked for Ur?rGi^lot°o^?5T/ °' """•"!?'" limestone, known by its'organic fosTib , (s« millstone ir?r','„dlhl„ ""•«'l»"«!<»» S'^'dish iron , in ?n a mX «rew a? one end.l" T"^- ^^"^ "^ '^ "^"""y ^ feet long, lermina ing eommll Ts'IclTn; "lUlro'm'TtchTaL^'a't?^^ ^^ boring chisel, a4 may be screwed, as occasion requires, to the brace-head/to Lke Te heVabive ihS mouth of the bore convenient for the hands of the men in working the rods. Henca the series of rods becomes a scale of measurement for noting the depth of the bore, and keeping a journal of the strata that are perforated. The brace-head rod, also 18 inches long, has two large eyes or rings at its top, set at right angles to each other, through whFch arms of wood are fixed for the men to lift and turn the rods by, in the bormg process. When the bore is intended to penetrate but a few fathoms, the whole work may be per- formed directly by the hands ; but when the bore is to be of considerable depth, a lofty triangle of wood is set above the bore hole, with a pulley depending at its summit angle, for conducting the rope to the barrel of a windlass or wheel and axle, secured to the ground with heavy stones. The loose end of the rope is connected to the rods by an oval iron ring, called a runner ; and by this mechanism they may be raised and let fall in the boring ; or the same effect may be more simply produced by substituting for the wheel and axle, a number of ropes attached to the rod rope, each of which may be pulled by a man, as in raising the ram of the pile engine. In the Newcastle coal district there are professional master-borers, who undertake to search for coal, and furnish an accurate register of the strata perforated. The average price of boring in England or Scotland, where no uncommon difficulties occur, is six shillings for each of the first five fathoms, twice 6 shillings for each of the second five fathoms, thrice 6 shillings for each of the third five fathoms, and so on ; hence the series will be — 1st five fathoms . - - - 2d five fathoms - - - - 3d five fathoms - - - - 4th five fathoms - - - - 20 fathoms of bore - - - £15 Thus the price increases equably with the depth and labor of the bore, and the under- taker usually upholds his rods. There are peculiar cases, however, in which the expense greatly exceeds the above rate. The boring tools are represented in the following figures : — 1076 16 .. 14 ., .- 11 9 13 IS (1 9 19 a/ Fig, 1076. 1. The brace-head, 2. The common rod. 3. The double-box rod; intermediate piece. 4. The common chisel. 6. The indented chisel. 6. Another of the same. 7. The cross-mouthed chisel. 8. The wimble. 9. The sludger, for bringing up the mud. 10. The rounder. 11. The key for supporting the train of rods at the bore-mouth. 12. The key for screwing together and asunder the rods. 13. The topit, or top-piece. 14. The beche, for catching the rod when it breaks in the bore. 15. The runner, for taking hold of the topit. 16. The tongued chisel. 17. The right-handed worm screw. 18. The left-handed do. 19. The finger grip or catch. We shall now explain the manner of conducting a series of bores in searching ground for coal. , Fig, 1077 represents a district of country in which a regular survey has proved the existence and general distribution of coal strata, with a dip to the south, at here shown. In this case, a convenient spot should be pitched upon in the north part '^1 ' \ N i 398 PITCOAL. ot the district, so that the successive bores put down may advance in the line of the 3 1077 4 5 B PITCOAL. 399 nrnhrhk? ^c / /k ' Perforation, many diversfties and alternations of strata will be Tamv an^thl '''"^•^' ^' T-''l ^". '^' '''''^''' «^ '^^ ^^^^^a ; each of which, as to ?"seen to nPni^^T'fi' '' ""^^ ? ^\' J""'""^^' ^"^ ^^P^cimens are preserved. This bore hat^he din nf th^« t . ^^u^^ ^' ^' ^ ?'' '^'*'^"' encountering any coal. Now, suppose r?n 1 ?n ^ of the strata be one yard m ten, the question is, at what distance from bore WO. 1, m a south direction, will a second bore of 60 yards strike the first stratum, d, of L fin win"" A Tu^ "^^^ obviously is, to multiply the depth of the bore by the dip, that f 1 ..IaY^ the product, 600, gives the distance required; for, by the rule of three, II 1 yard ol depression corresponds to 10 in horizontal length, 60 yards of depression will correspond to 600 in length. Hence the bores marked 1, 2, 3, 4, and 5, are succe " sively distributed as in the figure, the spot where the first is let do^n being'r^a;ded as the point of level to which the summits of all the succeeding bores are referred! Should k1 n^^L r X'- J^'^ ^^ ^? ^f ^' ^'^^^' **^ ^""^^^ ^^^" t^e t«P «f No. 1, allowance must be made for this diflerence m the operation ; and hence a surface level survey is requisite. Sometmies ravmes cut down the strata, and advantage should be taken of them, when they are considerable. ' In No. 2, a coal is seen to occur near the surface, and another at the bottom of the bore ; the latter seam resting on the first stratum rf, that occurred in bore No. 1 ; and No. 2 perforation must be continued a little farther, till it has certainly descended to the stratum rf. Thus these two bores have, together, proved the beds to the depth of 120 yards. No. 3 bore being placed according to the preceding rule, will pass through two coal- seams near the surface, and after reaching to nearly its depth of 60 yards, i1 will touch the ^ ratum J, which is the upper stratum of bore No. 2; but since a seam of coal was detected in No. 2, under the stratum h, the proof is confirmed bv running the borer down through that coal. The field has now been probed to the depth of 180 yards. The fourth bore is next proceeded with, till the two coal-seams met in No. 3 have been pene- trated ; when a depth of 240 yards has been explored. Hence No. 4 bore could not reach the lower stratum a, unless it were sunk 240 yards. The fifth bore (No. 5) being sunk in like manner, a new coal-seam occurs within a few yards of the surface; but after sinking to the depth at which the coal at the top of the fourth bore was found, an entirely different order of strata wiU occur. In this dilemma, the bore should be pushed 10 or 20 yards deeper than the 60 yards, to ascertain the alternations of the new range of superposition. It may happen that no coals of any value shall be found, as the figure indicates, in consequence of a slip or dislocation of the strata at b, whic^ has thrown up all the coals registered in the former borings, to such an extent that the strata 6, a, of the first bore present themselves immediately on perforating the slip, instead of lying at the depth of 300 yards (5 X 60), as they would have done, had no dislocation intervened. Some coal-fields, indeed, are so intersected with slips a^ to bewilder the most experienced miner, which will particularly happen when a lower coal IS thrown upon one side of a slip, directly opposite to an upper coal situated on the other side of it; so that if the two seams be of the same thickness, erroneous conclusions are almost inevitable. When a line of bores is to be conducted from the dip of the strata towards their out- crop they should be placed a few yards nearer each other than the rule prescribes, lest the strata last passed through be overstepped, so that they may disappear from the regis- ter, and a valuable coal-seam may thereby escape notice. In fact, each successive Iwre shou.d be so set down, that the first of the strata perforated should be the last passed through in the Preceding bore ; as is exemplified by viewing the bores in the retrograde direction, Nos. 4, 3, and 2. But if the bore No. 2 had gone no deeper than /, and the bore No. 1 had been as represented, then the stratum c, with its immediately subjacent coal, would have been overstepped, since none of the bores would have touched it ; and they would have remained unnoticed in the journal, and unknown. When the line of dip, and consequently the line of bearing which is at right an^^les to It, are unknown, they are sought for by makin? three bores in the following position —Let Jig. 1078 be a hoi izontal diagram, in which the place of a bore, No 1 it shown, which reaches a coal-seam at the depth of 50 yards; bore No. 2 may be made at B 300 yards from the former ; and bore No. 3 at c, equidistant from Nos. 1 and 2, ' so that the bores are sunk at the three angles of an B equilateral triangle. If the coal occur in No. 2 at the depth of 30 yards, and in No. 3 of 44 yards, it is manifest that none of the lines a b, b c, or c a, is in the line of level, which for short distances may be taken for the line of bearing, with coal-seams of mo- derate dip. But since No. 1 is the deepest of the three bores, and No. 3 next in depth, the line a c joining them must be nearer the line of level than either of the lines a b or b c. The question is, there- fore, at what distance on the prolonged line b c is the point for sinking a bore which would reach the coal at the same depth as No. 1, namely, 50 yards. This problem is solved by the following rule of proportion : as 14 yards (the difference of depth between bores 2 and 3) is to 300 yards (the distance between them), so is 20 (the difference of depth betwixt 1 and 2) to a fourth proportion, or x = 428 yards, 1 foot, and 8 inches. Now, this distance, measured from No. 2, reaches to the point d on the prolonged line b c, under which point d the coal will be found at a depth of 50 yards, the same as under a. Hence the line a d is the true level line of the coal-field ; and a line b f g, drawn at right angles to it, is the true dip-line of the plane which leads to the outcrop. In the present example the dip is 1 yard in 14| ; or 1 in 14 J, to adopt the judicious language of the miner ; or the sine is 1 to a radius of 14|, measured along The line from b to f. By this theorem for finding the lines of dip and level, the most eligible spot in a coal-field for sinking a shaft may be Suppose the distance from b to g in the line of dip to be 455 yards ; then, since every 14| gives a yard of depression, 455 will give 30 yards, which added to 30 yards, the depth of the bore at b, will make 60 yards for the depth of the same coal-seam at g. Since any line drawn at right angles to the line of level a d is the line of dip, so any line drawn parallel to a d is a level line. Hence, if from c the line c e be drawn paral- lel to D A, the coal-seam at the points e and c will be found in the same horizontal plane, or 44 yards beneath the surface level, over these two points. The point e level with c may also be found by this proportion : as 20 yards (the difference in depth of the bores under b and a) is to 300 yards (the distance between them), so is 14 yards (the difference of depth under b and c) to 210 yards, or the distance from B to e. As boring for coal is necessarily carried on in a line perpendicular to the horizon, and as coal-seams lie at every angle of inclination to it, the thickness of the seam as given obliquely by the borer, is always greater than the direct thickness of the coal ; and hence the length of that line must be multiplied by the cosine of the angle of dip, in order to find the true power of the seam. Of fitting or vnnning a coal-field.— In sinking a shaft for working coal, the great obstacle to be encountered is water, particulariy in the first opening of a field, which proceeds from the surface of the adjacent country ; for every coal-stratum, however deep it may lie in one part of the basin, always rises till it meets the alluvial cover, or crops out, unless it be met by a slip or dike. When the basset-edge of the strata is covered with gravel or sand, any body or stream of water will readily percolate downwards through it, and fill up the porous interstices between the coal-measures, till arrested by the face of a slip, which acts as a valve or flood-gale, and confines the water to one com- partment of the basin, which may, however, be of considerable area, and require a great power of drainage. In reference to water, coal-fields are divided into two kinds: 1. level free coal ; 2. coal not level free. In the practice of mining, if a coal-field, or portion of it, is so situated above the surface of the ocean that a level can be carried from that plane till it intersects the coal, all the coal above the plane of intersection is said to be level free ; but if a coal-field, though placed above the surface of the ocean, cannot, on account of the expense, be drained by a level or gallerj', but by mechanical power, such a coal-field is said to be not level free. Besides these general levels of drainage, there are subsidiary levels, called off-lakes or drifts, which discharge the water of a mine, not at the mouth of the pit, but at some depth beneath the surface, where, from the form of the country, it may be run off level free. From 20 to 30 fathoms off-take is an object of considerable economy in pumping ; but even less is often had recourse to; and when judiciously contrived, may serve to inter- cept much of the crop water, and prevent it from gelling down to the dip part of the coal, where it would become a heavy load on a hydraulic engine. Day levels were an object of primary importance with the early miners, who had not the gigantic pumping power of the steam-engine at their command. Levels ought ic be no less'^than 4 feet wide, and from 5 feet and a half to 6 feet high ; which is large 400 PITCOAL. PITCOAL. Ml \ 1 '¥' i m VHf' enonghfor carrying off waer, and admitting workmen to make repairs and clear out depositions. When a day-level however, is to serve the double purpose of drainage and an outlet for coals, it should be nearly 5 feet wide, and have its bottom gutter covered over. In other instances a level not only carries off the water from the col- hery, but is converted into a canal for bearing boats loaded with coals for the market. Some subterranean canals are nine feet wide, and twelve feet high, with 5 feet depth of water. '^ If in the progress of driving a level, workable coals are intersected before reaching the seam which is the main object of the mining adventure, an air-pit may be sunk, of inch dimension as to serve for raising the coals. These air-pits do not in general exceed 7 feet m diameter; and they ought to be always cylindrical. fLi019 represents a coal-field where the winning is made by a day-level; a is the mouth fj A f ll'^ ""^n "" ^^""S "^'^^ ^^^ ^^^ 5 b, c, d, e are intersected coal-seams, to be drained by the gallery. But the coals beneath this level must obviously be drained by pumping. A represents a coal-pit sunk on the coal e; and if the gallery be pushed 1079 -^ ^ forward, the coal-seams /, g, and any others which lie in that direction, will also be ^ined and then worked by the pit a. The chief obstacle to the execuron of day! kvels, IS presented by quicksands in the alluvial cover, near the entrance of the galled The best expedient to be adopted amid this difficulty is the following —F^ 1080 ltrZTf'^\'''^'^.''^r?,'T^-^'^^ ^' ^^^^ *he alluvial earth a I' contaii?n^ the bed of quicksand 6. The lower part, from which the gallery is required to be carried IS shown by the line b d. But the quicksand makes it^impossibL to push forward this day-level directly. The pit b c must therefore \^ sunk through the quTck- sand by means of tubbing (to be presently described), and when the pit has descended a tZr/^^" TV^' '^^' the gaUery or drift may then be pushed forward to the poinTr! when the shaft e d is put down, after it has been ascertained by boring that the rockl Sftl "'l^Hn'; fy.'J'' 'l^f ^"^,*V^ - - '--^ y-ds higher than the mouth of the smaU pit B. Durmg this operation, all the water and mine-stuff are drawn off by the pit b • ?« iii"^ !;^rVn I f^^ ^""'^ ^""-*^' ^"^^ communication with the gallery, the wateJ tnlTZ '^^" ''r'T "" '° ^^*''? "!" "P ^'^ '^^^' ^"1 i^ o^^^flo^s at the orifice " From the surface of the water m the deep shaft at g, a gallery is begun of the common dimensions, and pushed onwards till the coal sought after is intersectSl. In this waHo ^^S^^:^r a'btdtv'cS: '-'^^"^^"^ ^^"^^' ^'^ ^'"^ '-- ^' ^^ ^--«^ ^^P^-> When a coal-basin is so situated that it cannot be rendered level free, the winnine rfcltTeta^e ?- ""' •''"'""''-"^- The engine, at present en>ployed S Z dTT.;^! 1. The water-wheel, and water-pressure engine. 2. The atmospheric steam-engine of Newcomen. 3. The steam-engine, both atmospheric and double stroke, of Watt. 4. 1 he expansion steam-engine of Woolf. -ru 5* Tu*^® high-pressure steam-engine without a condenser, nnwpr nf C '• ♦ ^t! ^^^^^.^^^ ^ ^^u, OT to be drained of moisture, regulates the power of the engine to be applied, taking into account the probable quantity of water which may be found, a circumstance which governs the diameter of th2 working brrrete of the pumps. Experience has proved, that in opening collieries, even in new fieWs «cernt^rL'tr" ^ '' '"^" ^^ '^ P^-^P^ «^ ^^^^ ^0 t« ^5 inches diLeter; m^T^^ndl aIIT^ r'^ connected with rivers, sand-beds filled with water, oi flii- ^H ^^^^'^ ""^ "^^^^^ ^^«"™ *'ive'^ or sand-beds may be hindered f^m .Srnt^nnr/"?''''/^" growth proceeding from these sources neid not rtaSn i^to c^off Lrn thVlit'"'"^^^^^ '^"i^^"^ shafts, that though the influx which canno be for a liSrwhnpTpt' T\u^ *' ^'. ^"^y ^''^'^ ^^^" »>^y°"d the power of the engine for a little while, yet as this excessive flow of water is frequently derived from the foTsT 10 W? V 7fT''^^. ^•'^"™? manageable. An e%ine lorl/nTtheTuii^ uL Zhll ZZT ,^^\ ^''/ ""'^'^^""'^ «^^^«^te to the winning of a new col- heiy, which reaps no advantage from neighboring hydraulic powers. In the couri of years, however, many water-logged fissures com! to be cut b^the workings, and the e^uT^n'd f^J'^'T"^ T^:i' '^' ^"^"°P' ^ t^^t ^ <^«°«tant increasf if water ensues, and thus a colliery which has been long in operation, frequently becomes heav ly loaded with water, and requires the action of its hydraulic machinery both nighV and day. Of Engine Pits. — In every winning of coal, the shape of the engine-pit deserves much consideration. For shafts of moderate depth, many forms are in use ; as circular, oval, square, octagonal, oblong rectangular, and oblong elliptical. In pits of inconsider- able depth, and where the earthy cover is firm and dry, any shape deemed nM)St convenient maybe preferred; but in all deep shafts, no shape but the circular should be admitted. Indeed, when a water-run requires to be stopped by tubbing or cribbing, the circular is the only shape which presents a uniform resistance in ever\' point to the equable circumambient pressure. The elliptical form is the next best, when it deviates little from the circle; but even it has almost always given way to a considerable j)ressure of water. The circular shape has the advantage, moreover, of strengthening ^he shaft walls, and is less likely to suffer injury than other figures, should any failure of the pillars left in working out the coal cause the shaft to be shaken by subsidence of the strata. The smallest engine-pit should be ten feet in diameter, to admit of the 1083 1082 1081 pumps being placed in the lesser segment, and the coals to be raised in the larger one, as shown in fig, 1801 which is called a double pit. If much work is contemplated in drawing coals, particularly if their masses be large, it would be advantageous to make the pit more than 10 feet wide. When the area of a shaft is to be divided into three compartments, one for the engine pumps, and two for raising coals, as in fg. 1082 which is denominated a triple pit, it should be 12 feet in di- ameter. If it is to be divided into four compartments, and made a quadrant shaft, as in /??. 1088 with one space for the pumps, and three for ventilation and coal drawing, the total circle should be 15 feet in diameter. These dimensions are, however, governed by local circumstances, and by the proposed daily discharge of coals. The shaft, as it passes through the earthy cover, should be securely faced with masonry of jointed ashler, havin? its joints accurately bevelled to the centre of the circle. Speci- fic directions for building the successive masses of masonry, on a series of rings or cribs of oak or elm, are given by Mr. Bald, article Mine, Brewsier^s EncyclopcfdiOy p. 336. , ^ . ^ When the alluvial cover is a soft mud, recourse must be had to the operation of tubbing, A circular tub, of the requisite diameter, is made of planks from 2 to 3 incheslhick, with the joints bevelled by the radius of the shaft, inside of which are crib* of hani wood, placed from 2 to 4 feet asunder, as circumstances may require. These cribs are constructed of the best heart of oak, sawn out of the natural curvature of the wood, adapted to the radius, in segments from 4 to 6 feet long, from 8 to 10 inches in the bed, and 5 or 6 inches thick. The length of the tub is from 9 to 12 feet, if the layer of mud have that thickness ; but a succession of such tubs must be set on each other, provided the body of mud be thicker. The first tub must have its lower edge thinned all round, and shod with sharp iron. If the pit be previously secured to a certain depth, the tub is made lo pass within the cradling, and is lowered down with tackles till it rests fair among the soft alluvium. It is then loaded with iron weights at top, to cause it to sink down progressively as the mud is removed from its interior. Should a sin<»lc tub not reach the solid rock (sandstone or basalt), then another of like 1084 construction is set on, and the gravitating force is transferred to the top. Fig. 1084 represents a bed of quicksand resting on a bed of impervious clay, that immediately covers the rock, a is the finished shaft ; a a, the quicksand ; 6 6, the excavation necessarily sloping much outwards; c c, the lining of masonry ; d d, the moating or puddle of _ ^ clay, hard rammed in behind the stone-work, to render the latter water-tight. In this case, the quicksand, being thin in body, has been kept under for a short period, by the hands of many men scooping it rapidly away as it filled in. But the most effectual method of passing through beds of quick- sand is by means of cast-iron cylinders; called, therefore, cast-iron tubbing. When the pit has a small diameter, these tubs are made about 4 feet high, with strong flanges, and bolt holes inside of the cylinder, and a counterfort ring at the neck of the flange, with brackets ; the first tub, however, has no flange at its lower edge, but is rounded to facilitate its descent through the mud. Should the pit be of large diameter, then the cylinders must be cast in segments of 3, 4, or more pieces, joined together with inside vertical flanges, well jointed with oakum and white lead. When the sand-bed is thick, eighty "feet, for instance, it is customary to divide that length into three sets of cylinders'^ each thirty feet long, and so sized as to slide within each other, like the eye tubes of a telescope. These cylinders are pressed down by heavy weights, taking care to Vol. II. 3 F h ; 402 PITCOAL. The engine pit being secured, the process of sinking through the rock is ready to be commenced as soon as the divisions of the pit form'ed of cipentrrcalleJ b^^^^ are made. In common practice, and where great tightness of jointiris not reoS f?; ventilating inflammable air, bars of wood, 'called buntons, aC finches tS and 9 int^^n ?'f '" ^ horizontal posiUon across the pit, at distances from each mher of lO 20, or 30 feet, according to circumstances. Being all ranged in the same vertical d ane t^l' fV''"u ^".^ u ^^^^ '^'""^ ^'•^ "^"^^ ^« '^'^> ^-i^h «heir joints perfLuy cLse • one half of the breadth of a bunton being covered by the ends of the deals In deeo dUs where the ventilation is to be conducted through the brattice, the side of the buntons S < Uie pumps IS covered with deals in the same way, and the joints are ^Udered secure bv being calked with oakum. Fillets of wood are also fixed all the way down on each side of the brattice, constituting what is called a double pit. y u wn on eacn side -^nn*"^" rlh^^K^'^ have 3 compartments, it requires more care to form the brattice as none of the buntons stretch across the whole space, but merely meet near the Sdd^e' and join at certain angles with each other. As the buntons mus[ therefore sistaCTeach rt r '"'" ?K ^'T^l^ °^ '^ ^''^* '^'^^ ^'^ "«* J^id i" » horizontal plane! bit have a . rise from the sides towards the place of junction of 8 or 9 inches%nd are Zind S n'n ^ * three-tongued iron strap. Fillets of wood are carri5^' down the whole depth, not merely at the joinings of the brattice with the sides of the pit but a^so at ^n"* ''tH tK •'^^'k °^"^^°V ,^^^'^" '"""^'^ P"'^'-^ *^«""e<^^ the centre of each se of bun Ind'sUffness?'' "''"' ^"'^ '''''^- ^'"' ^'^ ^"^^^"^^^ ^^^^^ ^^^i^^^^ sufficient strength In quadrant shafts the buntons cross each other towards the middle of the pit and are generally let into each other about an inch, instead of bein- half-checked 7^1 inSi IS a double shaft : a the pump pit; b, the W for raising c'oalS^^^^^^ shaft ;m which A IS the pump compartment ; b and c are coal-pits. fI. 083 s a S Sr^ratji'g co'alf '""' ''' ' ^' ^' ^' ^^"^"^^^°" ^' "^^^^ ^-' ^« smofij^fandTpiu" A depth of 75 fathoms is fully the average of en-ine pits in Great Britain In practice, it embraces three sets of pumps. Whenever the shaft is sunk so low thai the engine IS needed to remove the water, the first set of pumps may be let down bv the method represented in fig. 1085 ; where a is the pump ; S, a, strong ear hrou^h wh ch ^lOSo^ pass the ,ron rods connected with the spears 6 6 ;% c are the fasWngs ; rf, he hoggar pump; e, the hoggar;//, the tackles; g g, the single spears By this mechanical arrangement the pumps are sunk in the most gradual manner, and of their own accord, so to speak, as the pit descends 7Z ,T' ""^ '^f 'f'!?'^'?'' '^^-^' ^'^ ^^«ten^ with ropes or chains •' ttf'J '^='%^'' loaded with weights, as counterpoises to^he weight of the column of pumps, and when additional pumps are joined in more weight IS laid on the sledges. As the sinking se^f pumps fscinstrtlv descending, and the point for the delivery of the water above a w^sva^! ing, a pipe of equal diameter with the pumps, and about 11 feet lonV bit much lighter m the metal, is attached to e, and is terminated by a hose of irlTVhir^^'TJ'l^V'' '•««<=^ the cistern where the wafer is deliv- enti ^t^the w r* '^' hoggar-pipe. In sinking, a vast quantity of iL enters with the water, at every stroke of the engine ; and therefore the lift ^frrf .tp '^"^^ ^' ""V ^^"^' ^'^^ ^ momentary stop should take plac^ before the returning stroke, to suffer all the air to escape. As the woSin^ fZ7rRt:rl'^ ^^ '^'r' ^^"-^"^ the fun strokf of the enl „! .vP!v'"^^ ll"^-^*" ^""'.^ ""^^ °^ P"°^PS» ^s from 25 to 30 fathoms. When- ever this depth is arrived at by the first set, preparations a7e made for PITCOAL. 403 y\ BtUUI BTit although from 20 to 30 fathoms be the common length of a pump-lift, it some. times becomes necessary to make it much longer, when no place can be found in the 1086 shaft for lodging a cistern, on account of the tubbing. Hence a pump-lift has Ubeen occasionally extended to 70 fathoms ; which requires extraordinary strength of materials. The best plan for collaring the pumps in the pit, and keeping them steady in a perpendicular line, is to fix a strong bunton of timber under the joints of each pipe ; and to attach the pipes firmly to these buntons by an iron collar, with screws and nuts, as represented in Jig. 1086. The water obtained in sinking through the successive strata is, in ordinary' cases, conducted down the walls of the shaft ; and if the strata are compact, a spiral groove is cut down the sides of the shaft, and when it can hold no more, the water is drawn off in a spout to the nearest pump-cistern ; or a perpendicular groove is cut in the side of the shaft, and a square box-pipe either sunk in it, flush with the sides of the pit, or it is covered with deal boards well fitted over the cavity. Similar spiral rings are formed in succession downwards, which collect the trickling streams, and conduct them into the nearest cistern ; or rings, made of wood or cast iron, are inserted flush with the sides of the pipe ; and the water is led from one ring to another, through perpendicular pipes, until the undermost ring is full, when it delivers its water into the nearest pump-cistern. Keeping the shaft dry is very important to the comfort of the miners, and the durability of the work. When an engine shaft happens to pass through a great many beds of coal, a gallery a few yards long is driven into each coal-seam, and a bore then put down from one coal to another, so that the water of each may pass down through these bores to the pump- cisterns. , While a deep pit is sinking, a register is kept of every part of the excavations, and each feeder of water is measured daily, to ascertain its rate of discharge, and whether it increases or abates. The mode of measurement, is by noting the time, with a seconds watch, in which a cistern of 40 or 50 gallons gets filled. There are three modes of keeping back or stopping up these feeders , by plank tubbing ; iron tubbing ; and by oak cribs. Let fig. 1087 represent the sinking of a shaft through a variety of strata, having a top cover of sand, with much water resting on the rock summit. Each plane of the coal-measure rises in a certain direction till it meets the alluvial cover. Hence, the pressure of the water at the bottom of the tubbing that rests on the summit of the rock, is as the depth of water in the superficial alluvium ; and if a stratum a affords a great body of water, while the superjacent stratum 6, and the subjacent c, are impervious to water ; if the porous bed a be 12 feet thick, while no water occurs in the strata passed through from the rock head, until that depth (supposed to be 50 fathoms from the surface of the water in the cover) ; in this case, the tubbing or cribbing mus sustain the sum of the two water pressures, or 62 fathoms ; since the stratum a meets the alluvial cover at d, the fountain head of all the water that occurs in sinking. Thus we perceive, that though no water-feeder of any magnitude should present itself till the shaft had been sunk lOO'fathoms; if this water required to be stopped up or tubbed oflf through the breadth of a stratum only 3 feet thick, the tubbing floodgate would need to have a stren^'th to resist 100 fathoms of water-pressure. For though the water at first oozes merefy in discontinuoui particles through the open pores of the sands and sandstones, yet it soon fills them up, like a i-jriad of tubes, which transfer to the bottom the totol weight of the hydrostatic column of 100 fathoms ; and experience shows, as we have already stated, that whatever water occurs in coal-pits or in mines, generally speaking, proceeds from the surface of lh« ground. Hence, if the cover be an impervious bed of clay very little water will be met with among the strata, in comparison of what would be found under sand. When several fathoms of the strata must be tubbed, in order to stop np the water- flow, the shaft must be widened regularly to admit the kind of tubbing that is to be inserted; the greatest width being needed for plank-tubbing, and the least for iron- tubbing. Fig. 1088 represents a shaft excavated for plank-tubbing, where a, a, a are the 1088 impervious strata, 6, b the porous beds water-logged, and c, c the bottom of the excavation, made level and perfectly smooth with mason- chisels. The same precautions are taken in working oflf the upper part of the excavation d, d. In this operation, three kinds of cribs are employed ; called wedging, spiking, and main cribs. Besides the stout plank for making the tub, a quantity of well-seasoned and clean reeded deal is required for forming the joints ; called sheeting deal by the workmen. This sheeting deal is always applied in pieces laid endwise, with the end of the fibres towards the area of the pit. Since much of the security from water depends on the 404 mcOAL. 1089 for Ihe loweTwXL cnib th. ^ii "i^P'"*"'"* J" /*• 1089. To make room ■m^H and from 4 to "SnT del f^eUM -n'"''''^ 'J^'' '»•="*' ^'''"' «* «' '-• ^'' of oakum is intrXced O^^iffK '^ ?"• """?."' "" ""='"' <" « "•'■> st™l"n> »1 "'""y joint- I, and at each of iu se^i„u'^^hee?^/de^?' i^''"fi™^» '""^''^ '" ">* "^"""i ; c^ii"ai^tl ind'^a^MS'^L^-^^^^^^^^ r.1rhaefof'"r the second spiking crib? is fixed and Inn^i;^ / r'l"?."* 'J"^'"" ^"'^ ^^^^^ «" ^ound, U.e°bti:aS'"7V sTnterdeV'"" °'' '"^ ""' "^X' '■™"' ^ "> ' f"' '-S, 10 inches in he««L?hlru^eLt't^'"^iJl„Th^"''r ''!}"•'"' ™^' '» segments, is likely iron, and its supS strength SSnraS' '^T i,"" ^'"" 'i'^''""™ '» '"« P"« «f in the circular Less oVTe'^. cu' ouTt'\tir^re«pUoT' Th^ f ""^ ''T 'IP'"" »oint is best turned inwards. Tn i«to ; J reception. The flange for the wedg ng Buddie, where il^eV^:r1\J:J:tto'^!^ZlT^^^^ --"^^^ by Mr^ feet Ion?, 2 feet broad and an m^iTii^l^i.- . hundred feet, the segments were 6 the back the % of the flan^rwa/.trnnf ' 'S""'"'^^'^!?.'"''^ "^^ «^ '^'^'^ ^«rk on of the iron cylinder axe set tfue to the rnflu/I'fP*'^ by brackets. These segments pendicular jLt is iTade t l^ht w^?h a JatV „f ^^^^^^^^ T"^' horizontal and per- at the bottom, and the se^e^ts arP h wu^f *'?",^^^^: ^ ^^^ging crib is fixed This kind of tubbrnVcanb^a^edt^^ iff ^ f'^? ^^^^ j°^"^« ^'^^ ashlerwork. surface, or till strata contafnfng water can be^ubW '\" ""T l^'^' *" ^"^^^^ «^ '^^ already described. A shaft finish^ in thf«m«^ ''^' ^^ ^^ *^^ '""^^^ °^ ^^^bing the flanges being turn^ tow^slhe out d^n? .h' ^'TT * 'T^'*' Mining-wall of iron" screw bdts are Leded for ,S^ th! ^pI ,V^ ?^^^^ ^" ^^^^ ^^«« tubbing, no in. the pit, like"^t''stv^S•'f'car'Xrf^^^ as they are packed hard ^h- trict, where 70 fathoms have been 7^r»iJ- V ^^^^K '" *^^ Newcastle dis- Buddle. ^^'^ executed m this way, under the direction of Mr. war,^ whCtTe t^ur'^'ofVe'Jj^L 'l' ^"^^"'^"^ ^'^'^ ^'^^ -^ --^ 1090 completdy s?Zed Vd bv ?h!\- ''^""^'''' ^'^ 7^^ ^"^y* ^^^ ^^^^^ <^an be — cuto^en with chTsels ^tol^d.h rr'"^ ^T"!.' ^C ^"^«^"^- ^he fissure ie sented m ^^1090 The Tn A • ''^*'' ^"? ? *^'J?'*' ^'^ ^^^^" ^"^^^^^ ^s repre- pieces ofcleL deal are thiP,.^"'"^ rounded off about an inch aid a half, contour of the lips . whe„ ?he wh"/"? "^^T ^^^^ ^T^^*^^^ "« ^''''^'' ^^an the stopped. By sloping b^ck the L^eVnfth^^^^ '' firmly wedged, till the water is entirely the stone, it is not liaWe to bui2 or orLi^ ff -"'t^ ^"^ "^^^^^"^ ^«^^ ^'■«'» t^^ f«ce of way, of driving in the wedge dTecSy "" ^^ operation, as took place in the old onX^SifetaTp^^uTJ^aS^^ the sinking of the shaft is going __ , -lighter i^ S^e co'mpVtmem t^^^^^ «^^ ^^"^ ^»^''»^' 'l square, n a Zrizontaldir";.?' ^"r '^ 'Y"^ * ^"*^^ «"« «^ ^^^^ 3 ffe to an ad^inTS ohf.^^'°"' from the mouth of that compartment fuuio w w leet square at bottom, and tapering upwards to 3 or 4 feet PITCOAL. 406 1091 lJMI Muare inside. Such a furnace and chimney are also needed for tentilating the coaL mine through all its underground workings. When a great quantity of gas issues fron one place in a pit, it is proper to carry it up in a square wooden pipe, which terminating at some distance above the surface in a helmet-shaped funnel, fitted to turn like a vane, may cause considerable ventilation of itself; or the top of such a pipe may be connected with a small fireplace, which will cause a rapid current up through it, from the pit. The stones and rubbish produced in sinking are drawn up with horse-gins, when the pit is not deep; but in all shafts of considerable depth, a steam engine is used, and the workmen have now more confidence in them, as to personal safety, than in machines impelled by horses. , « j- -j j The great collieries of Newcastle are frequently worked by means of one shall divided into compartments, which serves as an engine-pit, and coal-pits, and by these the whole ventilation is carried on to an extent and through ramifications altogether astonishing. This system has been adopted on account of the vast expense of a large shaft, often amounting to 60,000f. or 80,000/., including the machinery. The British collieries, how- ever are in general worked by means of an engine-pit, and a series of other pits, sunk at proper distances for the wants of the colliery. WORKING OF COAL. A stratum, bed, or seam of coal, is not a solid mass, of uniform texture, nor always of homogeneous quality in burning. It is often divided and intersected, with its con- comitant strata, by what are named partings, backs, cutters, reeds, or ends. Besides the chief partings at the roof and pavement of the coal seam, there are subordinate lines of parting in the coal mass, parallel to these, of variable dimensions. These divisions are delineated in fig, 1092 where A, d, c, d, e f g d, represent a portion of a bed of coal, „ c the parallelogram A b d c the parting at the roof, "X"^ 1092 and E F G the parting at the pavement ; ab,bc,de, and e /, are the subordinate or intermediate partings; g h, i fc, I m, the backs ; o /), p g, r », » <, a r, and v to, the cutters. It is thus manifest that a bed of coal, ac- ja cording to the number of these natural divisions, is sub- -a divided into solid figures of various dimensions, and of a "•g cubical or rhomboidal shape. When the engine-pit is sunk, and the lodgment formed, a mine is then run in the coal to the rise of the field, or a cropping from the engine-pit to the second pit. This mine may be 6 or 8 feet wide, and carried either in a line directly to the pit bottom, or at right angles to the backs or web of the coal, until it is on a line with the pit, where a mine is set off, upon one side, to the pit bottom. This mine or gallery is carried as nearly parallel to the backs as possible, till the pit is gained. Jtg. 1093 represents this 1093 * • ■ ■ '" ""'^ ~ "■ " " A is the engine-pit. by-pitr AC, the gallery driven at right angles to the backs, p c B, the gallery set off to the left hand, parallel to the backs. The next step is to drive the drip-head or main-levels from the engine-pit bottom, or from the dtp-hand of the backset immediately contiguous to the engine-pit bottom. In this business, the best colliers are always employed, as the object is to drive the gallery in a truly level direction, independently of all sinkings or risings of the pavement. For coal seams of ordinary thickness, this gallery is usually not more than 6 feet wide ; observing to have on the dip side of the gallery a small quantity of water, like that of a gutter, so that it will always be about 4 or 6 inches deep at the forehead upon the dip-wall. When the level is driven correctly, with the proper depth of water, it is said to have dead water at the forehead. In this operation, therefore, the miner pays no regard to the backs or cutters of the coal; but is guided in his line of direction entirely by the water-level, which he must attend to solely, without regard to slips or dislocations of the strata throwing the coal up or down. In the last figure, the coal-field is a portion of a basin ; so that if the shape be uniform and unbroken, and if any point be assumed a dipping from the crop, as d, the level lines from that point will be parallel to the line of crop, as d e, d f, and the levels from any point whatever a-dip- ping, will be also parallel to these ; and hence, were the coal-field an entire elliptical basin, the dip-head levels carried from any point would be elliptical, and parallel to the crop. If, as is more commonly the case, the coal-field be merely a portion of a basin, 1094 _ * _ formed by a slip of the strata, as represented in yig. 1094 ^^^''''^''Zji^Z^^^^ where a, o, a, is the crop, and a b, a slip of great magnitude, Ycy/' ^ ?""^^^Crf^ forming another coal-field on the side c, then the crop riot B c A only meets the alluvial cover, but is cut off by the slip at A and at b. Should any point, therefore, be assigned for an engine-pit, the levels from k will proceed in a line parallel *»> the crop, as d (2, d c, and the level on both sides v& mining operation. B, the second or 406 PITCOAL. PITCOAL. 4OT ^"„Te?; Tu' v'/li^e" r^ele'adf^o r "l r'" '«»«'"«.«'"= P-" incloded be. What is no, i«clad:dVu S;2i rhe^^XS^^Vr^^ the engine-pi. „ , WorWn^'w^r'n'n"* ""•". '"""'■ '"""'^"' *>-^'«'»^ <"" *»"'»? coal-mines - bent strata. excavated, as is just adequate to tlie support of tlie incom- erL^"ay"L*;ea«S Tlf h*"' "T """ "'■"'"^ ""= '«" "^ ="> «'™ ^i-c, and strong, a considSable portirof each ras^L'^^Mf '^ '"•'"'' ."■"" ""^ '"•«■"'»" "^ '•«'»°ving stall has been finiS Tn the coXe^ ^ ' *"™"" '*' "^^" """""g of post and the pits, whenever ther^nin?- ? s left, with the view of working back towards «od fhen Tak^ra; a^"""'^!'' "''*fVr "?i' ■"*""," '" ""^ «'»« of the coal-deld! 'T'tJirir-^ "^^^^^^^^^^^ '"^ """'^ ^"*'"- takes r.'ar?hecVaTL:.7«stve"irJs^^^^ '"^;''"'' ""'=•' "="« »» P""-' •>„. ben. strata erush d^tnrSrJ^erTcteTrttlJe: sTf^he ^lU^t' ^"'"' '"= *»'=""'- mel^'o^dr d'::;.t"'^eriU. Kifc l'" r-'^^ f -^ ""icTn":^- The Shropshire this mode has'beln'foSi^pTictiiabi;'"'' ' '"' ""'" '"* """""'^ '"'«•' « "' '<•«'. The followmg considerations must be had in view in establishing a coal mine • the' wo^rti irtrviittf rt^f::;it^of xrii" zt^ r ?^f F-r upper coals should be worked in the first place ' " '*""'" '^ '''"''' ">« ness of thVwiraTd eutTe^'""' '' '° ''"""' """'■'«'' ^""«^' '"« number and open- aess^'at i?s"^,ro whaTdirth"/t mlvyrj "»■"' """-"'^ « "> ""*- -<• -"- 6 The "^"' r "^ '?^»"""=" 'over of the ground, as to wa er nuicksands &c the •clf st™r "■" "' "''"' "'^-^' " «"«-"«' P«"'-'"'y if -rbfnr 't'he'^utcrop of ^^r^Bald gtves the following general rules for det^rmbirgthe best mode of working m^tfrottL^ntrel^h o^h^r^rLp^^dfnAo^^^^^^^ "r^T' '"' "'""' »■«> ™-^ providing all the coal prono«;d to be w?o^, J^,. ?f . J ° "'"''"' ^^'^''J^ «»P=ri"cumbent strata. Sit :','» =SSS E =■'" ?~=^^^^^^^ structionof the pillars, termedTm,^hnr«;-' if- ?'u^ °^ 7'''^'* ^^"^^ ^« « total de- Hoses up the Jrk. ' ""'*" ""^ ''^^ '"^ ^*^^^'^ ^^^ roof sinks to the pavement, and ^nlL'iZZ^^o:^^^^^^^^ P^^^- or an extra size are required, sued in the workin- but if ZylTsoh\hi^L^^"'^ ^f""'^- »°^»tioned may be pur- width, and with pillars of g eat e^fra strei^th bv whJnh T'^ ^'^^ '"^"^ «^ ^ '"^derate be got out at the last of the m^jS when the minpr«'j '*"! ^'^T' ^'''' ""^'^^ <^«^1 ^^7 finish the workings of a pit." ' ^ "'•"^'' '^*'^*' ^« ^^« P^^ l>ottom, and ther* me^^a^'p^SratVep^^^^^^^^ '^^ P-- and a room, with the roof str?tnmK//' ^^^ ^^'l^^its l^rge pillars Thus the riads w 11 be shut 1 ,h. '''°= ''^''" ^'^^"*^ ^* ^«"« ^^ a. Whole economy ofll/^S,?;^^^^^^^^^^^^ -^ ^he When an the eoai intenS^ ^T^Z::^.^^ ^J fi^^^^^ ^^^^ 1097 four fifths to two thirds ; but as the loss of even one third of the whol* area of coal ts far too much, the better mode of working suggested in the third system ought vo b« adopted. The proportion of a winning to be worked may be thus calculated. Let fig. 1097 be « "■ ""*' small portion of the pillars, rooms, and thirlings formed in a coal-field ; a, a, are two rooms j 6, the pillars ; e, the thirlings (or area worked out). Suppose the rooms to be 12 feet wide, the thirlings to be the same, and the pillars 12 feet on each side ; adding the face of the pillar to the width of the room, the sum is 24 ; and also the end of the pillar to the width of the thirling, the sum is likewise 24 : then 24x24=576 ; and the "5 S^ £ area of the pillar is 12X12=144; and as 576 divided by 144 gives 4 for a quotient, the result is, that one fourth of the coal is left in pillars, and three fourths extracted. Let rf, «,/, g, be one winning, and g, e, fc. A, another. By inspect- ing the figure, we perceive the workmgs of a coal-field are resolved into quadrangular areas, having a pillar situated in one of the angles. In forming the pillars and carrying forwards the boards with regularity, especially where the backs and cutters are very distinct and numerous, it is of importance to work the rooms at right angles to the backs, and the thirlings in the direction of the cutters, however oblique these may be to the backs, as the rooms are by this means conducted with the greatest regularity with regard to each other, kept equidistant, and the pillars 1098 are strongest under a given area. At the same time, however, il seldom happens that a back or cutter occurs exactly at the place where a pillar is formed ; but this is of no consequence, as the shearing or cutting made by the miner ought to be in a line parallel to the backs and cut- ters. It frequently happens that the dip-head level intersects the cut- ters in its progress at a very oblique angle. In this case, when rooms and pillars are set off, the face of the pillar and width of the room must be measured off an extra breadth in proportion to the obliquity, -..„^. as in fig. 1098. By neglect of this rule, much confusion and irregular work are often produced. It is, moreover, proper to make the fiist set of pillars next the dip-head level much stronger, even where there is no obliquity, in order to protect that level from being injured by any accidental crush of the strata. We shall now explain the different systems of working : one of the simplest of which is shown in fig. 1099 ; where a represents the engine-pit, b the by-pit, c d the dip-head levels, always carried in advance of the rooms, and E the rise or crop gallery, also carried in ad- vance. These galleries not only open out the work for the miners in the coal-bed, but, being in advance, afford sufficient time for any requisite operation, should the mines be obstructed by dikes or hitches. In the example before us, the rooms or boards are worked from the dip to the crop; the leading rooms, or those most in ad- vance, are on each side of the crop gallery e ; all the other rooms follow in succession, as shown in the figure ; consequently, as the rooms ad- 1^ — vance to the crop, additional rooms are begun at the dip-head level, towards c and d. Should the coal work better in a level-course direction, then the level rooms are next the dip-head level, and the other rooms follow in succession. Hence the rooms are carried a cropping in the one case, till the coal is cropped out, or is no longer workable ; and in the other, they are extended as far as the extremity of the dip-head level, which is finally cut off, either by a dike or slip, or by the boundary of the coal-field. When the winnings are so very deep as from 100 to 200 fathoms, the first workings are carried forward with rooms, pillars, and thirlings, but under a different arrangement, on account of the great depth of the superincumbent strata, the enormous expense incident to sinking a pit, and the order and severity of discipline indispensable to the due ventilation of the mines, the preservation of the workmen, and the prosperity of the whole establishment. To the celebrated Mr. Buddie the British nation is under the greatest obligations for devising a new system of working coal-mines, whereby nearly one third of the coals has been rescued from waste and permanent destruction. This system is named panel work ; because, instead of carrying on the coal-field winning in one extended area of rooms and pillars, it is divided into quadrangular panels, each panel containing an area of from 8 to 12 acres ; and round each panel is left at first a solid wall of coal from 40 to 50 yards thick. Through the panel walls roads and air-courses are driven, in order to work the coal contained within these walls. Thus all the panels are connected together with the shaft, as to roads and ventilation. Fach disUict or □ G Q O E E^P a Q m E3 ^B^Z3-tI7>tZ3E3-d 2E i'mn 408 PITCOAL. V. T' ims, was attended was attended with other very gr^Unconvenkrces If .S« '""k''^^ ^'"' '^^ «" "^^hod spot of the colliery, it was quite imposX Tai^'est fts nro'/r.^^ T '" ^^^ P*'^'*^"'" tf the ventilation was thereby obstructed, no ide^^oud hlZTJ'' l^^ "J^^^^'P^^ ^ ^^'^ be found, there being instances of no less than 30 mnil ? "'^ ^^^^^ ^he cause might And If from obstruct^ ventilation an explosion o^^^^^^ ""« «>"iery- workmen were occupied abng the extended waH flic . '"^^^ ^""'"'"^^ ^^"^ '"any where the disaster had taken place rnorcouW^h/vL' '^ '^^', "°* P«^«^»>^« »« determinJ bnng relief to the forlorn and mutuktS survte's """ ^"^ '"^"^^^^ ^»«^ ^^^^^ to In Mr. Buddie's system all these evils ar^ a„«r^^ JUKI foresight can go.' He makesIL p la^v?^^ w/f i"f^ ^^ ^" «« ^»°^«n science the pillars being in general 12 yards broaJl^nd I4 ^2^^ ? '*'^"'\**'' *^««"^^ "«"<>w ? wide, and the walls or thirlings cut through th! -if ^^"^^ ^°"^ ' t''^ ^ards 4 yards 6 feet wide, for the purpose of^venSlto^ A thl^ fil" ^T """ ^"^^ ^« another,'only proceeding from the dip to the crop, and the paneTwaI?r!.it^ 'T' ^'^ '^Presented as the area of the panel, to prevent the wei-hf nf tV ^^ *^ ^^'■"^^s thrown round running the adjoining panels. Again when thp i;/ '"Pf^'"<^""»>ent strata from over- rauge of pillars, as aluin hV is /rst at^'ed /n^LX t'T ^'' *" '^ ^«^^^^> «»« uttijiea , and as the workmen cut away the furthest pillars, columns of prop-wood are erected betwixt the pavement 8Jid the roof, within • few feet of each other (as shown by the dots), till an »rea of above 100 square yards ia cleared of pillars, presenting a body of strata perhaps 130 fathoms thick, suspended clear and without support, except at the line of the surrounding pillars. This operation is termed working the goaff. The only use of the prop-wood is to prevent the seam, which forms the ceiling over the workmen's heads, from falling down and killing them by its splintery fragments. Experience has proved, that before proceeding to take away another set of pillars, it is necessary to allow the last-made goaff to fall. The workmet then begin to draw out the props, which is a most hazardous employment. They begii at the more remote props, and knock them down one after another, retreating quickl) under the protection of the remaining props. Meanwhile the roof-slralum begins tc break by the sides of the pillars, and falls down in immense pieces ; while the workmei still persevere, boldly drawing and retreating till every prop is removed. Nay, should any props be so firmly fixed by the top pressure, that they will not give way to the blow» of heavy mauls, they are cut through with axes ; the workmen making a point of bona to leave not a single prop in the goaff. The miners next proceed to cut away the pillarr nearest to the sides of the goaff, setting prop-wood, then drawing it, and retiring as be fore, until every panel is removed, excepting small portions of pillars which require to be left under dangerous stones to protect the retreat of the workmen. "While this operatioi is going forward, and the goaff extending, the superincumbent strata being exposed with out support over a large area, break progressively higher up; and when strong beds ol sandstone are thus giving way, the noise of the rending rocks is very peculiar and terrific ; at one time loud and sharp, at another hollow and deep. As the pillars of the panels are taken away, the panel walls are also worked progres- sively backwards to the pit bottom ; so that only a very small proportion of coal is even- tually lost. This method is undoubtedly the best for working such coals as those of New- castle, considering their great depth beneath the surface, their comparative softness, and the profusion of inflammable air. It is evident that the larger the pillars and panel walls are, in the first working, the greater will be the security of the miners, and the greater the certainty of taking out, in the second stage, the largest proportion of coal. This system may be applied to many of the British collieries ; and it will produce a vast quantity of coals beyond the post and stall methods, so generally persisted in. In thus tearing to pieces the massive rocks over his head, the miner displays a deter- mined and cool intrepidity ; but his ingenuity is no less to be admired in contriving modes of carrying currents of pure atmospheric air through every turning of his gloomy labyrinth, so as to sweep away the explosive spirit of the mine. The fourth system of working coal, is called the long way, the long-wall, and the Shrop- shire method. The plan must at first have been extremely hazardous ; though now it is so improved as to be reckoned as safe, if not safer, to the workmen, than the other methods, with rooms and pillars. The object of the Shropshire system, is to begin at the pit-bottom pillars, and to cut away at once every inch of coal progressively forward, and to allow the whole superin- cumbent stratr 50 crush down behind and over the heads of the workmen. This plan is pursued chieriy with coals that are thin, and is very seldom adopted when the seam is 7 feet thick ; fiom 4 to 5 feet being reckoned the most favorable thickness for pro- ceeding with comfort, amidst ordinary circumstances, as to roof, pavement, &c. "When a pit is opened on a coal to be treated by this method, the position of the coals above the lowest seam sunk to, must first be considered ; if the coal beds be contiguous, it will be proper to work the upper one first, and the rest in succession downwards ; but if they are 8 fathoms or more apart, with strata of strong texture betwixt them, the working of the lower coals in the first place will do no injury to that of the upper coals, except breaking them, perhaps, a little. In many instances, indeed, by this operation on a lower coal, upper coals are rendered more easily worked. When the operation is commenced by working on the Shropshire plan, the dip-head levels are driven in the usual manner, and very large bottom pillars are formed, as represented in fig. 1101. Along the rise side of the dip-head level, chains of wall, or long pil- lars, are also made, from 8 to 10 yards in breadth, and only mined through occasionally, for the sake of ven- tilation, or of forming new roads. In other cases no a pillars are left upon the rise side of the level ; but, instead of them^ buildings of stone are reared, 4 feet broad at the base, and 9 or 10 feet from the dip side of the level. Though the roads are made 9 feet wide at first, they are reduced to half that width after the full pressure of the strata is upon them. "When Vol. II. 3 G 1101 !!!li H/.i\' M:. i in- :i; 410 PITCOAL. ever these points are secured. tb2 operation ol cutting away the whole body of the co»l begins. The place where the coal it removed, is named the gobb waste ; and gob- om, or gobb-stufl, is stones or rubbish taken away from the coal, pavement, or roof, to fill up that excavation as much as possible, in order to prevent the crush of superin- cumbent strata from causing heavy falls, or following the workmen too fast in their descent. Coals mined in this manner work most easily according to the wav in which the widest backs and cutters are; and therefore, in the Shropshire mode,' the walls stand sometimes m one direction, and sometimes in another ; the mine always turning out the best coals when the open backs and cutters face the workmen. As roads must be maintained through the crushed strata, the miners in the first place cut awav about 15 feet of coal round the pit-bottom piUars, and along the upper sides of the dip-head chain walls; and then, at the distance of 9 or 10 feet, carry regular buUdings of stone 3 feet broad, with props set flush with the faces of these, if necessary. As the miners advance, they erect small pillars of roof or pavement stone in regular lines with the wall face, and sometimes with props intermediate. There are two principal modifications of the Shropshire plan. The first, or the original system, was to open out the wall round the pit-bottom ; and, as the wall face* extended, to set ort mam roads and brandies, very like the branches of a tree. These roads were so distributed, that between the ends of any two branches there should be a distance of 30 or 40 yards, as might be most convenient. (Seeyig. 1101.) Each space of coal betwixt the roads is called a wall ; and one half of the coals produced from each wall is carried to the one road, and the other half to the other road. This is a great convenience when the roof IS bad ; and hence a distance of only 20 yards betwixt the roads is in many instances preferred. In fig. 1101 a represents the shaft ; b b, the wall-face ; a, the dip-head level • 6, the roads, from 20 to 40 yards asunder; c, the gobb or waste, with buildings along the sides of the roads ; and rf, the pillars. The other Shropshire system is represented in Jig. 1102 where a shows the pit, with the bottom pillars ; b, the dip-head levels ; c, the off-break from the level, where no pillars are left ; rf, the off-break, where pillars re- main to secure the level. All roads are protected in the sides by stone buildings, if they can be had, laid off 9 feet wide. After the crush settles, the roads generally remain permanently good, and can, in many cases, be travelled through as easily 50 years . u r ^u ■ ^^^^ they have been made, as at the first. Should stones not be %ihcoming coals must be substituted, which are built about 20 inches m the base. In this method, the roads are likewise from 20 to 40 yards apart ; but instead of ramifying, they are arranged parallel to each other. The miners secure the vasle by gobbing ; and three rows of props are carried forwards next the wall faces a, with pillars of stone or of coal reared betwixt them. This mode has a more regular appnarance than the other ; though it is not so generally practised. In the post and stall system, each man has his own room, and performs all the labor of It ; but in that of Shropshire, there is a division of labor among the workmen, who t^! S.V 1^ f^^ u\ '^'^^ companies. The first set curves or pools the coal klong the whole lineof walls laying m or pooling at least 3 feet, and frequently 45 inches! or D quarters, as it is called These men are named holers. As the crush is constantly following them, and impending over their heads, causing frequent falls of coal, they plant props of wood for their protection at regular distances lu an oblique direction between the pavement and wall face. Indeed, as a further precaution, staples of coaL about 10 inches square are left at every 6 or 8 yards, till the line of holing or curving IS completed. The walls are then marked off into spaces of from 6 to 8 yards in length! and at each space a shearing or vertical cut is made, as deep as the holingi and when ^u^L Th ^^""^' '"'"'l^- '' ^"^^^^^- The set who succeed the holers, are called nn Z* 1^ f ^'"ence their operations at the centre of the wall divisions, and drive out the gibbs and staples They next set wedges along the roof, and bring down pro- ^essively each div^on of coal; or, if the roof be hard-bound, the coal is blown down Toln^T .?hh. ^^' t ^^1^°"^,^^^ » ?««d Parting, the coals frequently fall down tTie moment the g.bbs are struck; which makes the work very easy. The getters are re- iT/oe^nV^nrnnT'^^'*'''^'!^ set, named butty-men, who break down The coaJslnTo LT h/lliT Tl""" ''f'''? "P '^^ ^^^' «"^ ^^^^ ^»^a^?e «f turning out the coal SZ- fil7^ i ?h' kk' ^"f'u^ '^^ '''^^'' ^^''' »>^'"^ done: they build up the stone pilars, fill up the gobb set the trees, clear the wall faces of all obstructions, set the gibbs and make every thing clear and open for the holers to resume their work. If luJlu to be heightened by taking down the roof, or removing the pavement, these butty-men do this work also, building forwards the sides of the roads, and sccu! nng them with the requisite props. When a coal has a following or roof stine, which regularly separates with the coal, this facilitates the Kbor, and saves much of the co^l • PITCOAL. 411 and should a soft bed of fire-clay occur a foot or two beneath the coal-seam, the holing is made in it, instead of into the coal, and the stone betwixt the holing and the coa benched down, which serves for pillars and gobbing. In this way all the vendible coa. becomes available. Another form of the Shropshire system is, for each miner to have from 6 to 12 leet ol coal before him, with a leading-hand man ; and for the several workmen to follow in succession, like the steps of a stair. When the coal has open backs and cullers, this work "oes on veiy regularly, as represented in Jig. 1103 where the leading miner is at a " next to the outcrop, and 6 6, &c. are the wall faces of each workman ; A being the shaft, and b the dip-head level. In this case the roads are carried either progressively through the gobb, or the gobb is entirely shut up ; and the whole of the coals are brought down the wall-faces, either to the dip-head level or the road c, c. This method may be varied by making the walls broad enough to hold two, three, or four men when each set of miners performs the whole work of holing, getting, breaking down, and carrying off the coals. It is estimated that from one eighth to one twelfth part only of the coals remains under ground by the Shropshire plan; nay, in favorable circuna- stances, almost every inch of coal may be taken out, as its principle is to leave no solid pillars nor any coal below, except what may be indispensable for securing the gobb. In- deed, this system might be applied to coal-seams of almost any ordinary thickness, provi- ding stuff to fill up the gobb could be conveniently procured. In Great Britain, seams of coal are mined when they are only 18 inches thick ; but if thinner, the working of fire-clay or ironstone immediately adjoining must be included. A few instances may be adduced, indeed, where caking coals of a fine quality for blacksmiths have been worked, though only in 12-inch seams. Eighteen-inch seams are best worked by young lads and boys. The coal itself may be mined without lifting the pavement, or taking down the roof in the rooms ; but roads must be cut either in the pavement or the roof, for removing the coals to the pit- bottom. All coals less than 2 feet 3 inches thick, are worked with the view of taking out all the coal, either on the Shropshire system, or with pillar-walls and rooms ; with this peculiarity, that, on account of the thinness of the seam, the rooms are worked as wide as the roof will bear up ; or if a following of the roof-stone, or fall of it, can be brought on, it proves advantageous, by not only giving head-room, but by filling up the waste, and rendering the roads easily kept for the working of the pillars. Where no fol- lowing takes place, small temporary pillars, about 8 feet square, are left along the chain- wall side. The walls may vary in thickness from 4 to 16 yards, according to circumstan- ces, and they are holed through only for ventilation. Coals from 5 to 8 feet thick are the best suited in every point of view for the effec- tive work of the miner, and for the general economy of underground operations. Whea they exceed that thickness, they require very excellent roof» and pavements, to render the working either safe or comfortable ; or to enable those who superintend the field to get out a fair proportion of coal from a given area. In such powerful beds the Shropshire method is impracticable, from want of gobbin ; and long props, unless of prodigious girth, would present an inadequate resistance to the pressure of the massive ceiling. When coals do not exceed 20 feet in thickness, and have good roofs, they are some- times worked as one bed of coal ; but if the coal be tender or free, it is worked as two beds. One half of such thick coal, however, is in general lost in pillars ; and it is very seldom that less than one third can be left. When the coal is free and ready to crumble by the incumbent pressure, as well as by the action of the air, the upper portion of the coal is first worked, then a scaffolding of coal is left, 2 or 3 feet thick, according to the ccmpactncss of the coal ; and the lower part of the coal is now worked, as shown in llu4 Jig, 1104. As soon as the workings are completed to the proposed extent, the coal scaftoldinars are worked away, and as much of the ^ pillars as can be removed with safety. As propwood is of no use in ^.v.,.v. c--,-.^ coal-seams of such a height, and as falls from the roof would prove frequently fatal to the miners, it is customary with tender roofs to leave a ceiling of coal from 2 to 3 feet thick. This makes ar excellent roof; and should it break, gives Warning beforehand, by a peculiar crackling noise, very different from that of roof-stones crushing down. One of the thickest coals in Great Britain, worked as one bed from roof to pavement, is the very remarkable seam near the town of Dudley, known by the name of the ten- yard coal, about 7 miles long, and 4 broad. No similar coal has been found in the island ; and the mode of working it is quite peculiar, being a species of panel work i 412 PITCOAL. PITCOAL. 413 I *■ totally different from the modern Newcastle system. A compartment or panel fbrm«l m working the coal, is called a side of work and as the STn^rrtion is^xhibU^ one of them before descnbing the whole extent of the workings of a mine. Let/f7. 1105 represent a side of work ; a, the ribs or walls of coal left standing roiinrl constuuung the side of work; a, the pillars, 8 yards square; c, the stat/ll^^^^^^^ ll"» dy}ne cross-openings, or through puts, also 11 yards wide; c, the bolt-hole, cut through the rib from the mam road, by which bolt-hole the side of work is opened up, and all the coals removed. Two, three, or even four bolt-holes open into a side of work, ac- cording to its extent ; they are about 8 feet wide, and 9 feet high. The working is in a great measure regu- lated by the natural fissures and joints of the coal- seam ; and though it is 30 feet thick, the lower band, of 2 feet 3 inches, is worked first ; the miners choosing to confine themselves within this narrow opening, in order to gain the greater advantage afterwarxls, in working the superjacent coal. Whenever the bolt hole IS cut through, the work is opened up by diivinir a gallery forward, 4 feet wide, as shown by the dotted lines. At the sides of this gallery next the bolt-hole, ♦«,^ J u J ^ ^ , ^^^'^ miner breaks off in succession a breast of coal two yards broad, as at /,/, by means of which the sides of the rib-walls a are forrn^' and the area of the pillars. In this way each collier follows anoth^ as in onP of thi systems of the Shropshire plan. When the side of work LZ!d open aling the rib-wa Is and the faces and sides of the pillars have been formed, the upper coals arrthenbe4n to be worked, next the nb-wall. This is done by shearing up to a bed next the bolt ho e and on each side, whereby the head coals are brought regSlarly d^n fn toe cuS Tu"' fr^ ^'^p "^'^ r ^"!!! ^^^^ ^^^ ^''' P*^^^?« of subiJdinTte diSs of the X^^lX^etuZZti:^:' ^^^" ^"^^ ^^"-^'-« ^^-^ ^^ convenient' t^ the coal Hence, from four tenths to a half of the total amount is lost fi? ever " Another method of working coal of uncommon thickness is by scafibldin-s ir sta-et of coals, as practised m the great coal bed at Johnstone, near Paisley, of whFch a sectbi has already been given. In one part of the field the coal is from 50 to 60 feet tS uoT '\ ^"'''""'' n ^^ ^'"f; "^^^ '"^"^ °^ ^'^^^ interspersed through the ^ 1 10b coal are generally inconsiderable, and amount in only two cases to 27 inches in thickness. The roof of the coal is so unsound, and the height so pro! t^T^J ?*' *' ^'V""^'* J^""} P^^'^'y ^^ ^'^'^^^ »n o"e seam, like that of Staffordshire. About 3 feet of the upper coal is therefore left as a roof under which a band of coal, from 6 to 7 feet thick, is worked on the pS and stall plan, with square pillars of extra strength, which are thereafter penetrated. A p atform about 3 feet high is left at the sole ; under which the rooms and pillars are set off and worked in another portion of the coah from D to 7 feet thick, great care being had to place pillar under pillar. anl<^™»/« that a large proportion of it is lost, as in the * K . • r .Staffordshire mines. Much attention must here be paid to the vertical dis- tribulion of the pil ars and apartments ; the miner's compass must be continually con^ sulcd and bore-holes must be put down through the coal scaffoldings, to re^ rectly the position of the pillars under one another. fe^uiaie cor- Edge coals, which are nearly perpendicular, are worked in a peculiar manner; for the collier stands upon the coal having the roof on the one hand, and the floor on the oJher! __- ^ i aJ a . llff /7 vertical walls. The engine-pit is sunk in the most pow! '■"■-^-^^ ^■ ■ - ' ■""'■ " " ^'^^^ ^t'-al"'"- In some instances the same stratum is so vertical is to be sunk through for the whole depth of the shaft. \N henever the shaft has descended to the required depth, galle- ,™« ,=™;s* ■'? '"'■^,^7^-^ ?<=^«ss the strata from its bottom, till the coals are MDlQllll I'JTr. . %k' '' '•''"'". ^" ^^' ^^^^ ^^^^^ ^^ «^« '^^ edge-coal, iuimi Limmi/i. a a, «; a, the engine-pit; 6, 6, the transverse galleries from the 1 ♦ 1 ^j 1^^^ ^^ ^ h^^^^i ^ i ^fc 1 i ^K J ^ ^^^^^ '^ ^ ^^tt^ ^ p ^^t s ^ L^^gL^ P5^ ^ ■^^ B«U bottom of the Shaft ; and c, c, upper transverse ' gaYleVl^r^Mk;' ^^;;te;"c;n^^^^^^ The principal edge coal works in Great Britain lie in the neigh working the coal. borhood of Edinburgh, and the coals are carried on the backs of women from the wall, face to the bottom of the engine-pit. The modes of carrying coals from the point where they are excavated to the pit bottom are nearly as diversified as the systems of working. One method employs hutches, or baskets, having slips or cradle feet shod with iron, containing from 2 to 3 hundred weight of coals. These baskets are dragged along the floor by ropes or leather harness attached to the shoulders of the workmen, who are either the colliers or persons hired on purpose. This method is used in several small collieries; but it is extremely injudicious, exercising the muscular action of a man in the most un- profitable manner. Instead of men, horses are sometimes yoked to these basket-hurdles, which are then made to contain from 4 to 6 hundred weight of coals ; but from the mag- nitude of the friction, this plan cannot be commended. An improvement on this system, where men draw the coals, is to place the basket or corve on a small four-wheeled carriage, called a tram, or to attach wheels to the corve itself. Thus much more work is performed, provided the floor be hard ; but not on a soft pavement, unless some kind of wooden railway be laid. The transport of coals from the wall-face to the bottom of the shaft was greatly facilitated by the introduction of cast-iron railways, in place of wooden roads, first brought into practice by Mr. John Curr of Sheffield. The rails are called tram-rails, or plate-rails, consisting of a plate from 3 to 4 inches broad, with an edge at right angles to it about two inches and a half high. Each rail is from 3 to 4 feet long, and is fixed either to cross bearers of iron, called sleepers, or more usually to wooden bearers. In some collieries, the miners, after working out the coals, drag them along these railways to the pit bottom ; but in others, two persons called trammers are employed to transport the coals ; the one of whom, in front of the corve, draws with harness ; and the other, called the palter, pushes behind. The instant each corve arrives, from the wall-face, at a central spot in the system of the railways, it is lifted from the tram by a crane placed there, and placed on a carriage called a roUey, which generally holds two corves. Whenever three or four rolleys are loaded, they are hooked together, and the rolley driver, 1108 with his horse, takes them to the bottom of the engine-shaft. The rolley O horses have a peculiar kind of shafts, commonly made of iron, named « limbers, the purpose of which is to prevent the carriage from overrunning them. One of these shafts is represented in^g. 1108. The hole shown at a passes over an iron peg or stud in front of the rolley, so that the horse may be quickly attached or disengaged. By these arrangements the work is carried on with surprising regularity and despatch. The power of the engine for drawing the coals up the shaft is made proportional to the depth of the pit and the quantity to be raised, the corves ascending at an average velocity of about 12 feet per second. So admirable is the modern arrangement of this operation, that the corves are transported from the wall-faces to the pit bottom, and moved up the shaft, as fast as the onsetters at the bottom, and the banksmen at the top, can hook the loaded and empty corves on and off the engine ropes. Thus 100 corves of coals have been raised every hour up a shaft 100 fathoms deep, constituting a lift of 27 tons per hour, or 324 tons in a day, or shift of 12 hours. Coals mined in large cubical masses cannot, however, be so rapidly raised as the smaller coal of the Newcastle district. When coals have so great a rise from the pit bottom to the crop that horses cannot be used on ilie rolley ways, the corves descend along the tram-roads, by means of inclined- plane machines, which are moved either by vertical rope-barrels, or horizontal rope- sheaves. These inclined planes are frequently divided into successive stages, 200 or 300 yards long, at the end of each of which is an inclined-plane machine, whereby the coaU are lowered from one level to another. The wheels of the trams and rolleys vary in diameter from 8 to 16 inches, according to the thickness of the coal. In some, the axles not only revolve on their journals, but the wheels also revolve on their axles. Various forms of machines have been employed for raising the coals out of the pits. The steam engine with fly-wheel and rope-barrels is, however, now preferred in all con- siderable establishments. When of small power, they are usually constructed with a fly wheel, and short fly-wheel shaft, on which there is a small pinion working into the teeth of a large wheel, fixed upon the rope-barrel. Thus the engine may move with great rapidity, while it imparts an equable slow motion to the corves ascending in the shaft. When the engines are of great power, however, they are directly connected with the rope-barrel ; some of these being of such dimensions, that each revolution of the rope- barrel produces an elevation of 12 yards in the corve. A powerful brake is usually con- nected with the circumference of the fly-wheel or rope-barrel, whereby the brakeman, by applying his foot to the governing lever of the brake, and by shutting at the same time the steam valves with his hands, can arrest the corve, or pitch its arrival withm a ■ i . 414 PITCOAL. PITCOAL. 416 I II # fhTh'?. ? ?^ required height of every delivery. An endlesg chain, suspended from the bottom to the top of the shaft, has, in a few pits of moderate depth, been worked by fnnnTh.fhl!;"^' Tor raising corves m constant succession j but the practice has not beei found hitherto applicable on the greater scale. r^J.y^l'ifJl!^^'"'* of water engines for raising coals, strictly admissible only in level free whh w.tPr wT'V^ '^' load^ cor^^e is produced by the descent of a cassoon fiUed ThTnlfrl ^ r ^^ ^^^""^ ^'^^ '^^''^^"^ ^""^ ^•^'■""^^ «q»al spaces, the rope barrels for coairhTvrtoh the corves are of equal diameter; but when the point frL which the coals have to be lifted is deeper than the point of discharge for the water into the dry level, the cassoon must be larger, and the ro|>e barrel smaller ; so that by the time the al^fuZr"^"' '° ^\" half-depth, for example, the corve ma^ have mounted through double the space. The cassoon is filled with water at the pit mouth, and is emptied by a Belf-actmg valve whenever it gets to the bottom. The loaded corve is replaced by an emp y one at the pit mouth, and its weight, with that of the descending rope, pull up the empty cassoon ; the motions of the whole mechanism being regulated b>' a powerful Various plans have been devised to prevent collision between the ascending and de- scendmg corves, which sometimes pass each other with a joint velocity of 20 or 30 feet per second. One method is by dividing the pit from top to bottom, so that each corve SlTiJ*^-* separate compartment. Another mode was invented by Mr. Curr of bhetfield in which wooden guides were attached from top to bottom of the pit : bein*' spars of deal about 4 inches square, attached perpendicularly to the sides of the shaft' and to buntons m the middle of the pit. Betwixt these guides, friction-roUer sliders are placed attached to the gin -ropes, to which sliders the corves are suspended. In this 1^^:! l^'V^^ ?r ^ '■^''^ u'''^*^ ^^^^ rapidity; but there is a considerable loss of 3 TM f !'\-°.Tk^ ^'^r^^/* r*'^^' "^^^'^ shutters or sliding boards must>be us«I. This plan is highly beneficial where the coals are in large lumps. Both ropes and chains are used for lifting coals. The round ropes are shroud-laid ; thi i' P'f "^^f L^^V ^^^ ?*' ^^I"^' '"^^^ «^ ^«"^ '^^' Pla««l horizontally together the ropes bemg laid alternately right and left. In this way, the ropes counteract one another in the twist, hanging like a riband down the shaft; and are stitched s?rong^y together by a small cord. Such rope bands are not only very pliable for their streneTh which protects the heart of the rope from breaking, but as they lap upon themselve! a St ,hr T'' ?." y«P«-^^-^i- They possess the additional ad^antge, Thaby^S nP^n^Sn ^U ''i/^^ "^'^Tl' ""^ '^^ ^^ ^" ^^'^*^ ^^^^ ^«"' ^"^ thus make a Im- Th^.. rrn^^"''-^ t^-'"'^ ^\' increasing length of rope descending with its corve. are'^oTtlf utl'^SeTcAB^K.'^ "'"' '^^ ''' "^^ '''"^ ^""'^ ^'^ ^^^^* P«dding-link chain, .n^^^ii^'ll"' ^"^' ^^'r " ^t^'i^^ '*'' ^^"^^*^ «^ *^« pit °»«"th» are drawn to the bin or ^nl t Ik^'m^*"" '^P' ^^ ^?'"'^'' °" ^y trammers on a tram-road. But with small TVr!V^^^X^'^''^h^^^ ^' ^"^^ i^ '^'''^ 8 or 9 feet above the commoT lev'Tof the ground, and the coal-heap slopes downwards from that height. As the bins increase tram-roads are laid outwards upon them. ^a i ic uius increase, n„L?!nnniT "^T"'^^ • ^^ Ventilation of coal mines. Into their furthest recesses, an ade- t^^onTI- ' %''^ J!' """'' ^^ '^'""^ forwards, for the purposes of respiration, and the combustion of candles; as also for clearing ofl* the carbonic acid and cal-bureted hy- drogen gases so destructive to the miners, who caU these noxious airs, from their mcwt obvious qualities, choke-damp and fire-damp. of ^thpTn«?^h!fr ^"^Z''' "^^^ ^PP]^^^ ^° ^^^ ^^^"^^^ °^ the t^^es, and the extraction ^LnLfpH in .hT^T'^J"" ^^'^ ^^ '"^h "'"ited extent, that when inflammable air ac- cumulated m the foreheads, it was usual in many coUieries to fire it every morninff This was done by fixing a lighted candle to the end of a lone pole, which bein<^ extendS safely over him. If the gas was abundant, the explosive miner pu on a wet jacket to prevent the fire from scorching him. In other situations, where the fire-dimp was stffl ZpndTfT: fX^""^^r\'^^"^^" ^^^^^^'^^ i"to it, by 'a cord passing oveTaTa tch S the end of the gallery, while the operator stood at a distance. This very rude and dan- fhTn-am^^f^S^efitr'/rnl '^' ^^^^^ ^-^^^ ^ ^ ^^ -i-^-^er The carbonic acid or choke-damp, having a greater specific gravity than atmospheric air, m the proportion of about 3 to 2, occupies the lower part of the workings, and gives comparatively ittle annoyance. Its presence may moreover be alwavs ife"v ascerJamed by the lighted candle. This cannot, however, be said of the fi7e-d1mp! which being lighter and more moveable, diffuses readily through the atmospheric 2rS as to form a most dangerous explosive mixture, even at a considerable distance from 1109 the blowers or sources of its extrication from the coal strata. Pure subcarbureted hy. drogen has a specific gravity = 0*555, air being 1 ; and consists of a volume of vapor of carbon, and two volumes of hydrogen, condensed by mutual affinity into one volume. The chok^-damp is a mixture of the above, with a little carbonic acid gas, and variable proportions of atmospheric air. As the pure subcarbureted hydrogen requires twice its bulk of oxygen to consume it completely, it will take for the same eflect about 10 times its bulk of atmospheric air, since this volume of air contains about two volumes of oxy- gen. Ten volumes of air, therefore, mixed with one volume of subcarbureted hydrogen, form the most powerfully explosive mixture. If either less or more air be intermixed, the explosive force will be impaired ; till 3 volumes of air below or above that ratio, con- stitute non-explosive mixtures; that is, 1 of the pure fire-damp mixed with either 7 or 13 (rf'air, or any quantity below the first, or above the second number, will aflbi-d an unex- plosive mixture. With the first proportion, a candle will not burn ; with the second, it burns with a very elongated blue flame. The fire-damp should therefore be still further diluted with common air, considerably beyond the above proportion of 1 to 13, to render the working of the mine perfectly safe. These noxious gases are disengaged from the cutters, fissures, and minute pores of the coal ; and if the quantity be considerable, relative to the orifice, a hissing noise is heard. Though the choke-damp, or carbonic acid gas, be invisible, yet its line of division from the common air is distinctly observable on approaching a lighted candle to the lower level, where it accumulates, which becomes extinguished the instant it comes within its sphere, as if it were plunged in water. The stratum of carbonic acid sometimes lies 1 or 2 feet thick on the floor, while the superincumbent air is perfectly good. When the coal has a considerable dip and rise, the choke-damp will be found occupying the lower parts of the mine, in a wedge form, as represented in ^g. 1109 where a shows the place of the carbonic acid gas, and 6 that of the common air. When a gallery is driven in advance of the other workings, and a discharge of this gas takes place, it soon fills the whole mine, if its direction be in the line of level, and the mine is rendered unworkable until a supply of fresh air is introduced to dislodge it. As the flame of a candle indicates correctly the existence of the choke-damp, the miners may have sufficient warning of its presence, so as to avoid the place which it occupies, till adequate means be taken to drive it away. The fire-damp is not an inmate of every mine, and is seldom found, indeed, where the carbonic acid prevails. It occurs in the greatest quantities in the coal mines of the counties of Northumberland, Durham, Cumberland, Stafl'ordshire, and Shropshire. It is more abundant in coals of the caking kind, with a bright steel-grained fracture, than in cubic coals of an open-burning quality. Splint coals are still less liable to disengage this gas. In some extensive coal-fields it exists copiously on one range of the line of bearing, while on the other range none of it is observed, but abundance of carbonic acid gas. In the numerous collieries in the Lothians, south from the city of Edinburgh, the fire damp is unknown ; while in the coal-fields round the city of Glasgow, and along the coasc of Ayrshire, it /requenlly appears. The violent discharge of the gas from a crevice or cutter of the coal, is called a blower ; and if this be ignited, it burns like an immense blowpipe, inflaming the coal at the opposite side of the gallery. The gas evidently exists in a highly compressed and elastic state, whence it seems to loosen the texture of the coals replete with it, and renders them more easily worked. The gas is often peculiarly abundant near a great dislocation or slip of the strata ; so that the fissure d' the dislocation will sometimes emit a copious stream of gas for many years. It has also happened, that from certain coals, newly worked, and let fall from a height into the hold of a vessel, so much inflammable gas has been extri- cated that, after the hatches were secured, and the ship ready to proceed to sea, the gas has isnited with the flame of a candle, so as to scorch the seamen, to blow up the decks, and otherwise damage the vessel. In like manner, when the pillars in a mine are crushed by sudden pressure, a great discharge of gas ensues. This gas, being lighter than common air, always ascends to the roof or to the rise of the galleries ; and, where the dip is considerable, occupies the forehead of the mine, in a wedge form, as shown iu P^^^^ fig. 1110 where a represents the fire-damp, and b the common air. 1110 B^^^^°^ ^ In this case, a candle will burn without danger near the point c, "^ — '' close to the floor ; but if it be advanced a few Jeet further to- wards the roof, an explosion will immediately ensue ; since at the lin .» where the two elastic fluids are in contact, they mix, and form an explosive body. When this gas is largely diluted with air, the workmen do not seem t( venience from breathing the mixture for a period of many years ; but ( carbureted hydrogen, the miner instantly drops down insf nsible, and, if >ot speedily re moved into fresh air, he dies. feel any incon- pure inhaling ■■•^-f 416 PITCOAL. riTCOAL. 417 m The production of these noxious gases renders ventilation a primary object in tht system of mining. The most easily managed is the carbonic acid. If an air-pipe has been carried down the engine pit for the purpose of ventilation in the sinking, other pipes are connected with it, and laid along the pavement, or are attached to an angle of the mine next the roof. These pipes are prolonged with the galleries, by which means the air at the forehead is drawn up the pipes and replaced by atmospheric air, which descends by the shaft in an equable current, regulated by the draught of the furnace at the pit mouth. This circulation is continued till the miners cut through upon the second sh^, when the air-pipes become superfluous ; for it is well known that the instant such com- munication is made, as is represented in Jig. 1111 the air spontaneously descends in the engine pit a, and, passing along the gallery a, ascends in a steady current in the second nil B pit B. The air, in sinking through A, has at first the atmospheric temperature, which in winter may be at or under the freezing point of water ; but its temperature increases in passing down through the relatively warmer earth, and ascends in the shaft b, warmer than the atmosphere. When shaf\s are of unequal depths, as represented in the figure, the current of air flows pretty uniformly in one direction. If the second shaft has the same depth with the first, and the bottom and mouth of both be in the same horizontal plane, the air would sometimes remain at rest, as water would do in an inverted syphon, and at other times would circulate down on,e pit and up another, not always in the same direction, but sometimes up the one, and sometimes up the other, according to the variations of temperature at the surface, and the barometrical pressures, as modified by winds. There is in mines a proper heat, pro- portional to their depth, increasing about one degree of Fahrenheit's scale for every 60 feet of descent. There is a simple mode of conducting air from the pit bottom to the forehead of the mine, by cutting a ragglin, or trumpeting, as it is termed, in the side of the gallery as rep- 1112 ^ presented in ^g. 1112, where a exhibits the gallery in the coal, and b the ^ — ^. ^fagglin, which is from 15 to 18 inches square. The coal itself forms three sides ot the air-pipe, and the fourth is composed of thin deals applied air-tisht, and nailed to small props of wood fixed between the top and bottom of the lips of the ragglin. This mode is very generally adopted in running galleries of communication, and dip-head level galleries, where carbonic acid abounds, or when from the stagnation of the air the miners' lights burn dimly. When the ragglin or air-pipes are not made spontaneously active, the air is sometimes impelled through them by means of ventilating fanners, having their tube placed at the pit bottom, while the vanes are driven with great velocity by a wheel and pinion worked with the hand. In other cases, large bellows like those of the blacksmith, furnished with a wide nozzle, are made to act in a similar way with the fanners. But these are merely temporary expedients for small mines. A very slight circulation of air can be effected by propulsion, in comparison of what may be done by exhaustion ; and hence it is better to attach the air-pipe to the valve of the bellows, than to their nozzle. Ventilation of collieries has been likewise effected on a small scale, by attaching a horizontal funnel to the top of air-pipes elevated a considerable height above the pit mfouth. The funnel revolves on a pivot, and by its tail-piece places its mouth so as to receive the wind. At other times, a circulation of air is produced by placing coal-fires in iron grates, either at the bottom of an upcast pit, or suspended by a chain a few fathoms down. Such are some of the more common methods practised in collieries of moderate depth, where carbonic acid abounds, or where there is a total stagnation of air. But in all great coal mines the aerial circulation is regulated and directed by double doors, called main or bearing doors. These are true air-valves, which intercept a current of air moving in one direction from mixing with another moving in a dif- ferent direction. Such valves are placed on the main roads and passages of the galleries, and are essential to a just ventilation. Their func- tions are represented in the annexed ^g. 11 13, where a shows the downcast shaft, in which the aerial current is made to descend; b is the upcast shafl, sunk towards the rise of the coal ; and c, the dip-head level. Were the mine here figured to be worked without any attention to the circulation, the air would flow down the pit a, and proceed in a direct line up the rise mine to the shaft b, in which it would ascend. The consequence would there- fore be, that all the galleries and boards to the dip of the pit a, and those lying on each fide of the pits, would have no circulation of air; or, in the language of the collier, would be laid dead. To obviate this result, double doors are placed in three of the galleries ad- joining the pit ; viz., at a and b, c and d, e and/; all of which open inwards to the shaft A. By this plan, as the air is not suffered to pass directly from the shaft a to the shaft b, through ! f • i tiie doors a and 6, it would have taken the next shortest direction hy e d and e/; but the doors in these galleries prevent this course, and compel it to proceed downwards to the dip-head level c, where it will spread or divide, one portion pursuing a route tc the right, another to the left. On arriving at the boards g and A, it would have natui-ally ascended by them ; but this it cannot do, by reason of the building or stop- ping placed at g and h. By means of such stoppings placed in the boards next the dip-head level, the air can be transported to the right hand or to the left for many miles, if necessary, providing there be a train or circle of aerial communication from the pit A to the pit b. If the boards t and k are open, the air will ascend in them, as traced out by the arrows; and after being diflfused through the workings, will again meet in a body at a, and mount the gallery to the pit b, sweeping away with it the deleterious air which it meets in its path. Without double doors on each main passage the regular circulation of the air would be constantly liable to interruptions and derangements; thus, suppose the door c to be removed, and only d to remain in the left hand gallery, all the other doors being as represented, it is obvious, that whenevei the door d is opened, the air, finding a more direct passage in that direction, would mount by the nearest channel /, to the shaft b, and lay dead all the other parts of the work, stopping all circulation. As the passages on which the doors are placed con- stitute the main roads by which the miners go to and from their work, and as the corves are also constantly wheeling along all the time, were a single door, such as d, so often opened, the ventilation would be rendered precarious or languid. But the double doors obviate this inconvenience ; for both men and horses, with the corves, in a:oing to or from the pit bottom a, no sooner enter the door d, than it shuts behind them, and encloses them in the still air contained between the doors d and c ; c having prevented the air from changing its proper course while d was open. When d is again slmt, the door c may be opened without inconvenience, to allow the men and horses to pass on to the pit bottom at a ; the door d preventing any change in the aerial circulation while'the door c is open. In returning from the pit, the same rule is observed, of shut- ting one of the double doors, before the other is opened. If this mode of disjoining and insulating air-courses from each other be once fairly con- ceived, the continuance of the separation through a working of any extent, may be easily understood. When carbonic acid gas abounds, or when the fire-damp is in very small quan- tity, the air may be conducted from the shaft to the dip-head level, and by placing stoppings of each room next the level, it may be carried to any distance along the dip- head levels; and the furthest room on each side being left open, the air is suffered to diffuse itself through the wastes, along the wall faces, and mount in the upcast pit, as is represented in fig. 1099. But should the air become stagnant along the wall faces, stoppings are set up throughout the galleries, in such a way as to direct the main body of fresh air along the wall faces for the workmen, while a partial stream of air is allowed to pass through the stoppings, to prevent any accumulation of foul air in the wastes. In very deep and extensive collieries more elaborate arrangements for ventilation are introduced. Here the circulation is made active by rarefying the air at the upcast shaft, by means of a very large furnace placed cither at the bottom or top of the shaft. The former position is generally preferred. Fig. 834 exhibits a furnace placed at the top of the pit. When it surmounts a single pit, or a single division of the pit, the compartment intended for the upcast is made air-tight at top, by placing strong buntons or beams across it, at any suitable distance from the mouth. On these bunions a close scaffolding of plank is laid, which is well plastered or moated over with adhesive plastic clay. A little way below the scaffold, a passage is previously cut, either in a sloping direction, to connect the current of air with the furnace, or it is laid horizon tally, and then communicates with the furnace by a vertical opening. If any obstacle prevent the scaffold from being erected within the pit, this can be made air-tight at top, and a brick flue carried thence along the surface to the furnace. The furnace has a size proportional to the magnitude of the ventilation, and the chim- neys are either round or square, being from 50 to 100 feet high, with an inside diameter of from 5 to 9 feet at bottom, tapering upwards to a diameter of from 2^^ feet to 5 feet. Such stalks are made 9 inches thick in the body of the building, and a little thicker at bot- tom, where they are lined with fire-bricks. The plan of placing the furnace at the bottom of the pit is, however, more advan- tageous, because the shaft through which the air ascends to the furnace at the pit mouth, is always at the ordinary temperature; so that whenever the top furnace is neg- lected, the circulation of air throughout the mine becomes languid, and dangerous to the workmen ; whereas, when the furnace is situated at the bottom of the shaft, its sides- get heated, like those of a chimney, through its total length, so that though the heat of the furnace be accidentally allowed to decline or become extinct for a little, the circa- Vol. IL 3 H i: •^m 418 PITCOAL. 1115 To prevent the annoyance to the onsetters at the bottom, from the hot smoke, the fol- lowmgpianhas been adopted, as shown in the wood-cut, ^g. 1114 where a represents .^ .. the lower part of the upcast shaA ; b, the furnace, built of brick, arched at top, with its sides insulated from the solid mass of coal which surrounds it. Between the furnace wall and the coal beds, a current of air constantly passes towards the shaft, in order to prevent the coal calchine lire. From the end of the furnace a gallery is cut in a . ^. , ~ Q f .u - "Sing direction at c, which communicates with the shaft at ..^d, about Tor 8 fathoms Irom the bottom of the pit. Thus the furnace and furnace- beeper are completely disjoined from the shaft; and the pit bottom is not only Jr^ ■ES^ /s=r-1i iromall encumbrances, but remains comfortably cool. To ob. viate the inconveniences from the smoke to the banksmen in landing the coals at the pit mouth, the following plan has been contrived for the Newcastle collieries, ii-ig. 1115 represents the mouth of the pit ; a is tlie upcast shaft, provided with a furnace at bottom ; b, the downcast shaft, by which the supply of at- mospheric air descends ; and rf, the brattice carried above the pit mouth. A little way below the settle-boards, a gallery c is pushed, m communication with the surface from the downcast ^^haft oyer which a brick tube or chimney is built from 60 to 80 feet ♦« r» *!. . o , . ^ > 7 or 8 feet diameter at bottom, and 4 or 5 feet diameter at top On the top of this chimney a deal funnel is suspended horizontally oi TpTvot like a turn-cap. The vane/, made also of deal, keeps he mouth of the funnel alwavs m the same direction with the wind. The same mechanism is mount^ at "he upcast shaft ., only here the funnel is made to present its mouth in the wind's eve. It is obvfous from the figure, that a high wind will rather aid than check the ventilatLi by this plan .nl]^^^^""'/- ^ f •''•'"'^^,V^" *^"^"^ ^^"^ established, the next object in openin/up a ^o / M ^*™P^«^"t very ingenious distribution of which, the circulation of idr depends at the commencement of the excavations. urcuiaiion oi air The double headways course is represented in fig. 1116., where a is the one heading or gallery, and 6 the other; the former bein| immediately connected wftS the upcast side of the pit c, and the latter with the downcast side of the pit d. The pit itself is made completely air-tight by its division of deals from top to bottom, called the brattice wall ; so that no air «(, pillar of coal; the pillars or walls of coal, marked e, are called stentinc walls • Vn/thi openings betwixt them, walls or thirlings.' The arrows show tte diKn of ?he ah- The headings a and 6 are generally made about 9 feet wide, the stSLwans 6 or 8 ..d downcast nils s.^rrL •'"''''.'•<»'«:'' '"'''=•' ""e circalation betwtat the upcast fi?.!- wJ , .1 earned on; but whenever the workmen cnt through the fir«. S^h?-'' ""-^ ^"''r "^ ". ""^ •"■""'■-'^ »' »>^ pi' l™""". "shut • in consequence of ruThTctf to'lh teh S' wTrr-the'^rnes" arrat'wtT"-?!: 'T" ^^ ""^'""I'l the last thirling through which ?he air was circu^LL .1 T '.''''•''"? 's. -"^^e. fsT'- '»•'"'-'-?«'."•« stXiu s^ piS°'^\h':tSn:^n'::mbered''rtt t'h?eh''Ue"s^lrrre\fa^stfter^rnt\T'^.'^-^^^^^^^^^^^ observe, that on this very simple pfan a stream ff.^^ ^J inspecting the figure, we distance, and in any diLtionThoweVer ,or,uo«s S be circulated to any required double headways course a, 6, is pushrf f^wari "ther 1^.^.. ^ ? " ' '"^ """'^ ""* luired to he carried nn ^t .1,. . '"rwara, other double headways courses are re- Lie^e'Se^ SeT htfUnoTXar tf 2 1^ ^rk^^^t^-^^^ 63 PITCOAL. the 419 a 18 the upcast, and b the downcast shaft. The air advances along the heading c, but cannot proceed further in that direction than the pillar rf, being obstructed by the double doors at e. It therefore advances in the direc- tion of the arrows to the foreheads at /, and passing through the last thirling made there, returns to the opposite side of the double doors, ascends now the heading g, to the foreheads at h, passes through the last-made thirling at that point, and descends, in the heading t, till it is interrupted by the double doors at k. The aerial current now moves along the heading l, to the foreheads at w, returns by the last-made thirling there, along the heading n, and finally goes down the heading o, and mounts by the upcast shaft a, carrying with it all the noxious gases which it encountered during its circui- tous journey. This wood-cut is a faithful representation of the system by which collieries of the greatest extent are worked and ventilated. In some of these, the air courses are from 30 to 40 miles long. Thus the air conducted by the medium of a shaft divided by a brattice wall only a few inches thick, after descending in the downcast in one compartment of the pit at 6 o'clock in the morning, must thence travel through a cir- cuit of nearly 30 miles, and cannot arrive at its reascending compartment on the other side of the brattice, or pit partition, till 6 o'clock in the evening, supposing it to move all the time at the rate of 2| miles per hour. Hence we see that the primum mobile of this mighty circulation, the furnace, must be carefully looked after, since its irregularities may affect the comfort, or even the existence of hundreds of miners spread over these vast subterraneous labyrinths. On the principles just laid down, it appears that if any number of boards be set off from any side of these galleries, either in a level, dip, or rise direction, the circulation of air may be advanced to each forehead, by an ingoing and re- turning current. Yet while the circulation of fresh air is thus advanced to the last-made thirling next the foreheads /, A, and in, fig. 1117 and moves through the thirling which is nearest to the face of every board and room, the emission of fire-damp is frequently so abundant from the coaly strata, that the miners dare not proceed forwards more than a few fevt from that aerial circulation, without hazard of being burned by the combustion of the gas at their candles. To guard against this accident, temporary shifting brattices are em- ployed. These are formed of deal, about | of an inch thick, 3 or 4 feet broad, and 10 feet long; and are furnished with cross-bars for binding the deals together, and a few finger loops cut through them, for lifting them more expeditiously, in order to place them in a proper position. Where inflammable air abounds, a store of such brattice deals should be kept ready for emergencies. The mode of applying these temporary brattices, or deal partitions, is shown in the accompanying figure (fig. 1118, which shows how the air circulates freely through the 1118 thirling rted by blowing fresh air from a smal pair of bellows through a stratum of water in the bottom of the lamp, while the heated air passed out t^^^^ough water by a recurved tube at top. By this means the air within the lamp was completelyinsulated from the surrounding atmosphere. This lamp was the first ever taken ^to a body of m flammable air in a coal-mine, at the exploding point, without setting fire to the gas around it. Dr. Clanny made another lamp upon an improved plan by introducing into it the steam of water generated in a small vessel at the top of the lamp, heated by the flame The chiefobjection to these lamps is their inconvenience in use. Various other schemes of safe-lamps were off-ered to the miner by ingemmis ^echam- cians, but they have been all superseded by the admirable invention of Sir H- Davy, founded on his fine researches upon flame. The lamp of Davy was instantly tried aiid approved of by Mr. Buddie and the principal mining engineers of the Newcastle district. A perfect security of accident is therefore afforded to the miner m the use of a lamp which transmits its light, and is fed with air, through a cylinder of wire gauze ; and this inyen- tion has the advantage of requiring no machinery, no philosophical knowledge to direct its use, and is made at a very cheap rate. . « ^. ^ , In the course of a long and laborious investigation on the properties of the firedamp, Md the nature and communication of flame. Sir H. Davy ascertained that the explosions o( inflammable gases were incapable of being passed through long narrow metallic tubes; and that this principle of securilv was still obtained by diminishing their length and diameter at the same time, and likewise diminishing their length, and increasing Itieir number, so that a great number of small apertures would not pass an explosion, when their depth was equal to their diameter. This fact led him to trials upon sieves made ol wire-gauze, or metallic plates perforated with numerous small holes ; and he found it wa? impossible to pass explosions through them. , _. The apertures in the gauze should never be more than l-20th of an inch square, in the working models sent by Sir H. to the mines, there were 748 apertures in the square inch, and the wire was about the 40th of an inch diameter. The cage or cylinder ol wire-gauze should be made by double joinings, the gauze being folded over in such a manner as to leave no apertures. It should not be more than two inches in diameter ; for in large cylinders the combustion of the fire-damp renders the top inconvenienUy .i^'^^— -iW II V I I ' III ill I : 424 PITCOAL. 3 -x. of 4 or 5 turns All ioinina, f„ tk! y^*'*^^'^ should be fastened to the lamp by a screw ID the wire gauze. ttperiure exists m the apparatus larger than distinct iia^e-peS:^ Ta HrZSfi:Z\li!^%^"^ """'' ^ -«^"" "' "»« When aVndle hu trfiS^^d , LfS'^aTtn'o'l':;'''?""'!!'"?'' ^"'■?^ """*"? «»■»*• of flame is wen of a fine skv hl.?^ «7.k S ™"n""' »"■. « d'stinct and wellnlefined cone yellow to the an'ei of The c„„^ R»l- 1 .k° ""' "*' "''"=''' »"<' «''«»'=<= "f « bright [he cone, whicrhets Lress^of ^T^:^^^^Zu7:iii'zvir'''^'' ^"^r""'"* be seen bv nlacino- onp nf th*. ho„^o I'^evenis ineeje Irom discernms:. This may candle. a„7a.nhldrancef\S;nT:':^th:t\h'el:a .'"'"'f ^''V"^ ""'r '"« yellow flame may be seen and no mnre Ri^:, 1 .^"" •"""' "'^ ""« »P" o*^ ">« will be distinctly' observed close to the a Jx'^of fh^v V' ^'"P' "'. '"* ™""' "^™ "' quarter of an inch in Ie™th ThU ton ifof /,S? '^ • ^I "°™^' {^"^ »" '='''"•' '» » tt^flame^XtlVwry^^^^^ s:'»t^-T^-ror^^^^^^^^^^^ entirely on the appearance which thi^haze assume, i^ T. ^'^"^1^^^, ^^ '"»?^'-^> ^^Pends the proportions of the'a^ious admSes ' "' '"' "'"^ modifications, according to of rd:s"UwrcS! :«? trflt^'tshtt t^nr Vh ^-Ih^^ ^^^ ^'^ -^^^• copious, the flame goes out, and the miSl'rs'immSiaTet reul e "^''"^ ''^^ '"^ ^^^" "^°^« Ms'^an'dleTanT advi'ncTs w^t'™camls°sretV ir^nl"'-^"^^.^^ ^^^ ^-^ ^"- screening 'the flame ^th ^e ri^ht andts'lhe^S^^^^^ rf '^ S!" '^' ^'^ '^"^' ^"^^ gallery next the roof, he holds the candle as low «« il ^ **,' ,'" ^^^ "PP^*" P**"^ **^ ^^^^ the tip, he moves forwards/ If the "as besrilnL^rit^^^ ^''P'"^ ^'l '^' ^^'^ «" without observing any material change in hfsl^h ^But f in hr'7'''^ ?' ^""''^'^ the tip to elongate, and take a bluish-gray color he is n,, t nn h' ^''*!!r ^^. ^^^^^''^^ with much caution ; and if the tip beein?L^n?rI L ^ P"^'"* '''^ »"^"*' ^"'^ ^^^PS on ing the candle near the pavement erSltrW?-* ^'"^P''/^^ «« one knee, and hold- gc^s as it approaches the r"of? ' If thel^Js bTcoP ou^^ the T"''''^ ''' '''^"--^^ ^' ""^^'- spire, as well as the top. It is in -eneral rlrknn»S ^ ' ""T elongates into a sharp the bluish-gray to a fine blue color'accomnW "^^^^ ^^^ ^'P <^h«"?« from rapidly upwari through the Sam^' an"tT"wh"en thTsv^' ""''^'"^ ^^K^' "''^^ P«^» OU8, a sudden movement of the hands or bodv is I^Wp ti^^"^' ^ -^ manifestly danger- of the fire-damp. The experienced minPrihpJ/ /"* V^"""^ *-"'^^°" ^^ agitation candle to the pavement, an^hen tu^ n' rou^^^^^^^^ ^"^ «»"^'°"^Jy ^^^ers his his right hand and extinguishes the flame with ht' I ^' ^'I l^^'^""^ ^^''^^y* ""' «^'P^ "P too far, and approach the tdy of gas In an exnln"?"" and thumb. Should he venture rapidly elongates, and the whole Wsefin a sharn ^n r'""^ condition, the tip of the candle the whole surrounding atmosphere is "„ a b W ?n TT^' '""'*"' ^" ^^"'^^ ' ^"'^ *^^" ravage is the consequence, to an extent proDortlonS f l""""" ^°.'"^'il ^"^ destructive Safety Lamp, and Venti^tion P'-oportioned to the quantity of fire-damp. See Almost every colUery, aAer' having ^:l'Tor^tr''^l ti:;:r^vXec;ri^^ .^S PITCOAL. 425 .he candle ; so that while in one mine liable to fire-damp an explosion will take place with a top less than an inch long, in another mine the top may be two inches high, and yet the air be considerably under the point of accension. These differences depend on several particulars. If the gas has not passed through a long course of ventilation, and is little mixed with air, it will ignite with a very short top ; while, on the other hand, a gas which has run through a ventilation of 20 or 30 miles may cause the production of a long top without hazard. It is hence obvious, that skilful experience, and thorough practical knowledge, are the only sure guides in these cases. We shall now describe briefly the modern modes of working coals a-dipping of, and deeper than, the engine-pit bottom. One of these consists in laying a working pump barrel with a long wind-bore at the bottom of the downset mine, furnished with a smooth rod working through a collar at the top of the working barrel. At one side of this, near the top, a kneed pipe is attached, and from it pipes are carried to the point ol delivery, either at the engine pit bottom or day level, as represented in j?g. 1123. The spears are worked sometimes by rods connected with the machinery at the 1123 1124 ■/ k ^ la a m surface; in which case the spears, if very long, i^re either sus- pended from swing or pendulum rods, or move on friction rollers. But since the action of the spears, running with great velocity the total length of the engine stroke, very soon tears every thing to pieces, the motion of the spears under ground has been reduced from 6 or 8 feet, the length of the engine stroke, to about 15 inches ; and the due speed in the pump is effected by the centring of a beam, and the attachment of the spears to it, as represented in yig. 1124, where a is the working barrel, 6 the beam centred at c, having an arc-head and martingale sinking-chain. The spears d are fastened by a strong bolt, which passes through the beam ; and there are several holes, b> means of which the stroke in the pumps can be lengthened or shortened at convenience. The movement of the spears is regulated by a strong iron quadrant or wheel at the bottom. In level-free coals, these pumps may be worked by a water-wheel, stationed near the bottom of the pit, impelled by water falling down the shaft, to be 'discharged by the level to the day (day-level). But the preferable plan of working under-dip coal, is that recently adopted by the Newcastle engineers ; and consists in running a mine a-dipping of lbs engine-pit, in such direction of the dip as is most convenient; and both coals and water are brought up the rise of the coal by means of high-pressure engines, working with a power of from 30 to 50 pounds on the square inch. These machines are quite under command, and, producing much power in little space, they are the most applicable for underground work. An excavation is made for them in the strata above the coal, and the air used for the furnace under the boiler, is the returned air of the mine ventilation. In the dip-mine a double tram-road is laid; so that while a number of loaded corves are ascending, an equal number of empty ones are going down. Although this improved method has been introduced only a few years back, under-dip workings have been already executed more than an English mile under-dip of the engine-pit bottom, by means of three of these high-pressure engines, placed at equal distances in the under-dip mine. It may hence be inferred, that this mode of working is susceptible of most extensive application ; and in place of sinking pits of excessive depth upon the dip of the coal, at an almost ruinous expense, much of the under-dip coal will in future be worked by means of the actual engine-pits. In the Newcastle district, coals are now working in an engine pit 1 15 fathoms deep under-dip of the engine-pit bottom, above 1600 yards, and fully 80 fathoms of perpendicular depth more than the bottom of the pit. If an engine-pit be sunk to a given coal at a certain depth, all the other coals of the 1125 coal-field, both above and below the coal sunk to, can be drained and worked to the same depth, by driving ^ a level cross-cut mine, both to the dip and rise, till all the coals are in- A k tersected, as represented in fig. 1125 where a is the engine-pit bottom reaching to the coal a ; and 6, c, d, e, /, coals lying above the coal a ; the coals which lie below it, g, A, t ; k is the forehead of the cross-cut mine, intersecting all the lower coals ; and /, the other forehead of the mine, intersecting all the upper coals. In the " Report from the select committee of the House of Lords, appointed to take into consideration the state of the coal trade in the United Kingdom," printed in June, 1829, under the head of Mr. Buddie's evidence we have an excellent description of the Vol. it. 8 I 426 PITCOAL. PITCOAL. 427 i i It nature and progress of creeps, which we have adverted to in the preceding account. The annexed Jig. 869 exhibits the creep in all its progressive stages, from its commence- ment until it has completely closed all the workings, and crushed the pillars of coal. The section of the figures supposes us standing on the level of the different galleries which are opened in the seam. The black is the coal pillars between each gallery ; when these are weakened too much, or, in other words, when their bases become too narrow foi the pavement below, by the pressure of the incumbent stratification, they sink down into the pavement, and the first appeaiance is a little curvature in the bottom of each gallery: that is the first symptom obvious to sight ; but it may generally be heard before it is seen. The next stage is when the pavement begins to open with a crack lonsitudinally. The next stage is when that crack is completed, and it assumes the shape of a metal ridge. The next is when the metal ridge reaches the roof. The next stage is when the peak of the metal ridge becomes flattened by pressure, and forced into a horizontal direction, and becomes quite close; just at this moment the coal pillars berm to sustain part of the pressure. The next is when the coal pillars take part of the pn The beds with which the coal is generally associated in the British islands are various sands and shales (imperfect slaty beds) of different degrees of hardness ; but the actual coal scams themselves often repose directly on clay of peculiar fineness, well adapted for fire bricks, and generally called under clay. The under clay is used in many coal districts for various purposes of pottery. Bands of ironstone (impure argillaceous carbonate of iron) are very abundant in certain coal districts, but are almost absent in others. The Scotch coal fields near Glasgow, the South Welsh and some others, are rich in ironstone, which is the chief source of the vast quantities of iron manufactured in this kingdom. The principal coal-fields of Europe apart from the British Islands are those of France, Belgium, Spain (in the Asturias), Germany (on the Ruhr and Saare), Bohemia, Silesia, and Russia (on the Donetz). Of these the Belgian are the most important, and occupy two districts, that of Li^ge and that of Hainault, the former containing 100,000 and the latter 200,000 acres. In each the number of coal seams is very considerable, but tho beds are thin and so much disturbed as to require special modes of working. The quality of coal is very various, including one peculiar kind, the Flenu coal, unlike any found in Great Britain except at Swansea. It bums rapidly with much flame and smoke, not giving out an intense heat, and having a somewhat disagreeable smell. There are nearly fifty seams of this coal in the Mons district. No iron has been found with the coal of Belgium. The most important coal-fields of France are those of the basin of Loire, and those of St. Etienne are the best known and largest, comprising about 50,000 acres. In this basia are eighteen beds of bituminous coal, and in the immediate neighbourhood several smaller basins containing anthracite. Other valuable localities are in Alsace, several in Bur- gundy much worked by very deep pits, and of considerable extent ; some in Auvergne with coal of various qualities ; some in Languedoc and Provence with good coal ; others at Arveyron ; others at Limosin ; and some in Normandy. Besides these are several others of smaller dimensions and less extent, whose resources have not yet been developed* The total area of coal in France has not been ascertained, but is probably not less than 2,000 square miles. The annual production is now at least 4,000,000 tons. There are four coal districts in Germany of the carboniferous period, besides several districts where more modern lignites occur. The principal localities for true coal are near the banks of the Rhine in Westphalia ; on the Saare, a tributary of the Moselle j in Bohemia and in Silesia, the total annual production exceeds 2,760,000 tons. Of these various localities, Silesia contains very valuable and extensive deposits of coal, which are as yet but little worked. The quality is chiefly bituminous, the beds few in number but very thick, amounting in some cases to 20 feet. Some anthracite is found. Bohemia is even more richly provided than Silesia, the coal measures covering a con- siderable area and occupying several basins. More than 40 seams of coal are worked, and several of these are from 4 to 6 feet thick. The basin of the Saare, a tributary of the Moselle, near the frontier of France, affords a very important and extensive coal field, which has been a good deal worked and is capable of great improvement No less than 103 beds are described, the thickness varying from 18 inches to 15 feet. It is estimated that at the present rate of extraction the basin contains a supply for 60,000 years. On the banks of the Ruhr, a small tributary to the Rhine, entering that river near Dusseldorf, there is another small coal field estimated to yield annually 1,000,000 tons. The whole annual supply from Prussia and the German States of the ZoUverein or Customs' Union, is considered to exceed 2,750,000 tons. Hungary and other countries in the east of Europe contain true coal measures of the carbomferous period ; but the resources of those districts are not at present developed. On the banks of the Donetz in Russia, coal is worked to some extent and is of excellent quality, but it belongs to the other part of the carboniferous period. Spam contains a large quantity of coal, both bituminous and anthracite. The richest beds are in Asturias, andl^the measures are so broken and altered as to be worked by almost vertical shafts through the beds themselves. In one place upwards of 11 distinct seams have been worked, the thickest of which is nearly 14 feet The exact area is not known, but it has been estimated by a French engineer that about 12,000,000 of tons might be readily extracted from one property without touching the portion existing at great depths. In several parts of the province the coal is now worked, and the measures seem to resemble those of the coal districts generally. The whole coal area is said to be the largest in Europe, presenting upwards of 100 workable seams varying from 3 to 12 feet in thickness. There are in North Anaerica four principal coal areas ; compared with which the richest deposits of other countries are comparatively insignificant These are the great central coal-fields of the Alleghanies ; the coal-fields of Illinois, and the basin of the Ohio ; that of the basin of the Missouri ; and those of Nova Scotia, New Brunswick, and Cape Breton. Besides, there are many smaller coal areas which, in other countries, might well take rank as of vast national importance, and which even in North America will one day contribute greatly to the riches of the various States. The Alleghany or Appalachian coal field measures 750 miles in length, with a mean breadth of 85 miles, and traverses eight of the principal States of the American Union. Its whole area is estimated at not less than 65,000 square miles, or upwards of 40,000 Bquare acres. The coal is bituminous and used for gas. In Kentucky both bituminous and cannel coal are worked in seams about 3 or 4 feet deep, the cannel being sometimes associated with the bituminous coal as a portion of the same seam ; and there are in addition valuable bands of iron ore. In Western Virginia there are several coal fields of variable thickness, one, 9i feet ; two others of 6, and others of 3 or 4 feet On the whole there seems to be at least 40 feet of coal distributed in 13 seams. In the Ohio district the whole coal field affords on an average at least 6 feet of coal. The Maryland district is less extensive, but is remarkable as containing the best and most useful coal, which is worked now to some extent at Frostbury. There appears to be about 30 feet of good coal in four seams, besides many others of less importance. Tlie quality is intermediate between bituminous and anthracite, and is considered well adapted for iron making. Lastly, in Pennsylvania, there are generally from two to five workable beds, yielding on an average 10 feet of workable coal, and amongst them is one bed traceable for no less than 450 miles, consisting of bituminous coal, its thickness being from 12 to 14 feet on the south-eastern border, but gradually diminishing to 5 or 6 feet Besides the bitu- minous coal there are in Pennsylvania the largest anthracite deposits in the States, occupying as much as 250,000 acres and divided in three principal districts. The Illinois coal field, in the plane of the Mississippi, is onlj^ second in importance to the vast area already described. There are four principal divisions traceable, of which the first, or Indian district, contains several seams of bituminous coal distributed over an area of nearly 8,000 square miles. It is of excellent quality for many purposes ; one kind burning with much light and very freely, approaching cannel coal in some of its properties ; other kinds consist of caking or splint coaL In addition to the Indian coal- field there appears to be as much as 48,000 square miles of coal area in other divisions of the Illinois district, although these are less known and not at present much worked. 80,000 are in the state of Illinois, which supplies coal of excellent quality, and with great facility. Tlie coal is generally bituminous. The third great coal area of the United States is that of the Missouri, which is little known at present, although certainly of great importance. British America contains coal in the provinces of New Brunswick and Nova Scotia. The former presents three coal-fields, occupying in all no less than 5,000 square miles; but the latter is far larger and exhibits several very distinct localities where the coal abounds. The New Brunswick coal measures include not only shales and sandstones, as is usual with such deposits, but bands of lignite impregnated with various copper ore, and coated by green carbonate of copper. The coal is generally in thin seama lying horizontally. It is chiefly or entirely bituminous. In Nova Scotia there are three coal regions, of which the Northern presents a total thickness of no less than 14,570 feet of measures, having 70 seams, whose aggregate magnitude is only 44 feet, the thickest beds being less than 4 feet The Pictou or central district, has a thickness of 7,590 feet of strata, but the coal is far more abundant, one seam measuring nearly 30 feet ; and part of the coal being of excellent quality and adapted for steam purposes. The southern area is of less importance. Besides the Nova Scotia coal-fields there are three others at Cape Breton, yielding different kinds of coal, of which one, the Sydney coal, is admirably adapted for domestic purposes. There are here 14 seams above 3 teet thick, one being 11, and one 9 feet Coal, existing generally in beds of moderate thickness inclined at a small angle to the horizon and often at a very considerable depth beneath the surface, is extracted most commonly by the aid of pits or shafts sunk to the bed and galleries (levels of drifts), cut horizontally or in the plane of the bed to a certain distance. By a number of such gal- leries cut at right angles to each other , the whole bed, within certain limits, is completely laid open, the overlaying beds being supported by masses of coal (pillars or columns) left untouched between the galleries ; in this way about one third of the coal can be ex- tracted, and afterwards, on the supporting columns being removed, the roof falls in and the work is regarded as finished. This method is called technically the " pillar and stall method," and is adopted in the Newcastle coal-field. In Yorkshire and elsewhere, instead of such columns being left, the coal is removed entirely and at once without columns ; the roof falling behind the work as it advances. This is the long wall method. Other modes are occasionally followed when the condition of the coal requires it Owing to the gaseous substances contained in coal and given off, not only on exposure to heat^ but also, to a certain extent^ by pressure, many kinds of coal cannot safely be left (i 488 PITCOAL. during the process of extraction without some defence from the open lights required by the miner m the mechanical operations of remoYing the coal from its bed and conveyini It to the pit bottom. An explosive gaseous compound is readily produced by the mS ture of the gases given off by the coal, with common air, made to circulate through the workmgs, and if neglected, this compound accumulates, and travels on till it meeta -mth flame, and then explodes, causing frightful destruction not only to the property of the mine owner, but also to the life of the miner. Many contrivances have been suggested from time to time, on one hand to improve the ventilation of the mines, And, on the other, providing means of illumination which would render accidents from explosion less probable, by removing the immediate cause. Examples of both will be found amongst the models and instruments exhibited in this class of the Exhibition. It 18 not likely that any contrivances can render absolutely safe an employment which of necessity involves so many and such serious risks as are connected with coal mining- but much may no doubt be done to diminish the danger both from imperfect venti&^ tion and open light In concluding this notice of mineral fuel, it may be worth while to draw attention to the vast and overwhelming importance of the subject by a reference both to the absolute and relative value of the material, especially in the British Islands. It may be stated as probably within the true limit, if we take the annual produce of the British coal mines at 36,000,000 tons, the value of which is not less than 18,000,000^. steriing, estimated at the place of consumption, and therefore including a certain amount of transport cost necessary to render available the raw material At the pit mouth the value of the coal is probably about half this, or 9,000,000/. sterling, and the capital employed m the coal trade is estimated at 10,000,000/. The average annual value of all the gold and silver produced throughout the worid has been estimated to have amounted in 184*7, to nearly thii-teen millions and three quarters sterling. We haveu thwefore, the following summary, which will not be without interest Value of the coal annually raised in Great Britain, estimated at the pit mouth - - - - . Mean annual value at the place of consumption Capital engaged in the coal trade Mean annual value of the precious metals obtained from North and South America and Russia Total value of precious metals raised throughout the whole world - - - . . Mean annual value at the furnace of iron produced from British coal - - - - 9,000,000 18,000,000 10,000,000 5,000,000 13,000,000 8,000,000 Boghead Coal. — ^At Boghead, near Bathgate, in Scotland, is a very valuable gas coaL The mineral substance so called is a true coal, and belongs to the great coal formation of this island. It differs in no essential respect from the Cannel coal found in the south- west of Scotland, in North Wales, and in many parts of England. It contains the same remains of plants which characterise the coal formation all over the world, that is to say, impressions of sigillarise, stigmariae, Ac In a chemical point of view, the resem- blance becomes much more striking, and is altogether so decisive that I do not hesitate to declare, in the most positive manner, my opinion that the Boghead coal is as much 8 coal as any other coal in the kingdom. The conchoidal fracture, the specific gravity, and the general habitude when burnt are precisely like those of the whole of the coal found in and around the Boghead dis- trict, and many striking points of resemblance maybe noticed in these and other respects between the Boghead and other coals from the south of Scotland, such as the Kirkness, the Arniston, the Wemyss, the Capeldrae, Ac, as well as with many from England, Wales, and even India, as will be shown hereafter. Thus the nature of the gases they evolve by heat is the same,--they are all proof against heated naphtha, oil of turpentme, aether, Ac— they are equally so against dilute alkaline and acid solutions—in -chemical composition they are alike— the ash is the same, and indicates a common origin, whereas, in these respects, all these coals differ totally from every form of bitumen, lignite, retinite, and bituminous shale which has yet come under my notice. It would be a work of supererogation to enter more fully into a detail of these parti- culars, nor is this at all necessary towards the completion of my proof I have asserted that the Boghead coal is a true coal, and belongs to the Cannef variety of that mineral In support of the assertion I append the following table of coals analysed for this pur- pose, and proving beyond all contradiction that it is not even at the extreme limit of the class to which it belongs^ but occupies a central and very unequivocal poaition in the Cannel coal eerie& prrcoAL. 439 Mum of SolMtanc*. New Bnuuwick As- phalt. Indian coal, No. 1. No.l Le>mahago Capeldrae Lockgelly Kirkness Old Wemysa - Boghead Brymbo Canael, Specific Gravity. Sheffield Cannel Portland Shale - No. No. Seyssell Asphalt 1098 1-363 1-290 1-220 1-227 1-320 1-215 1-325 1-223 1-574 1-520 1-526 1-766* 1-780' For Ce.it- •geof Combuiitibte Matters. 99-4 87-5 88- 90-9 89-5 86-9 86-5 84-9 77-2 66-8 68-8 66- 48-9 57-8 Per Cent. at A»h. Nmturaof A^ Silica 19-5 12- 91 10-5 131 135 15 1 228 332 31-2 34- 511 42-2 Trisilicate of alu- mina. Ditto - - - Ditto - - - Ditto . - - Ditto - Ditto - - - Ditto - Ditto - Ditto - Ditto - Ditto - Ditto - Carb,, phosphate, silicate of lime sand. Carbonate of only. Remarks. Largely soluble in naphtha, oil of turps, sther, and sulphuret of carbon. Insoluble in the abore and in dilute acids. Ditto ditto. Ditto ditto. Ditto ditto. Ditto ditto. Ditto ditto. Ditto ditto. Ditto ditto. Ditto ditto. Ditto ditto. -Ditto ditto. and; Slightly soluble, Acted with on with slight effer- Tescence. lime Largely soluble. Ra- pidly acted on with eflfervescence. pnvoAT tExhmi^^^^^^^^^^^ STernrrulte'^urt ;VetXtht^^^^^^ and its miiufacture. Our ancestors were producers ^^ ?<>?J-f7 'J>^^^ ^^l SaI^^^^I of this important agent belongs to the F^^ent century ; and ther^^^^^^^ *The P^duction elastic fluids or gases, with a triflm^ production of tar and ^^P\^^^^^^ however apt to induce some grave inconveniences, as ^"^ aPPf^^^^^^J-^f'^^iSj" i,_^ the gls maker, in ite first process, sails between «^ ^ind «^ ^.th! ^ItZ^ud^^^^^^^^ to dVead an excessive production of tar on the one hand, and the evils ^«^/"^^J^^^ Ihe other. Presuming however that, the P-per temperat^^^^^^^ has leen --red,^^; successful production of good coal gas is not yet ^^^^^^^^^^^^^^^^^ ^^^'^^ conductor introduction into the retort, are free, or neariy so, from water. Coal is a oaa couu ♦ \9tj variable. i I- 440 PITCOAL. of heat; and therefore when a quantity of this substance in a wet condition is throw, .^to a red-hot retort, as precisely by gas manufacturers, the ouTer po^tiorfTws m^ of th'rall'rb'^l'piT?^^^ "^"^ '•'^.^' '''\' long before the ^ater in the ce^^ of the coal has been expelled; consequently, as the heat penetrates through the coaL th^ water 18 vaporized, and driven in the form of steam over the red^b^t coke on tha I^ll^lnTf wh • V^ • '• "? "^ ^l^ ^^^^ "^"' ^^^'•^g-' carbonic oidf and Lr^^^^^^^ acid, all of wh ch are injurious to the gas maker ; the two first by diluting his cas and Wering its illuminating power; the last, by neutralizing the Kcontfined ?n the puriher, and thus needlessly causing an increased consumption o^ that article But the presence of water in coal is also determined in another way^ for teconver^k,n into .team implies the absorption of an immense amount of heat, slice the latent heat o^ steam is upwards of 960°; consequently, as this absorption tikes plLi imL.W.lv previous to the decomposition oflhe bituminous constitutes of the coal a dTsposS r^ults to generate at that time a temperature capable only of producinTtir or S C ?he 12/ briw ^' 'r°^"'^?? "' ^"'^'■^'^ ' */^ ^^"« ^'^''^^^' onl/tends to rS tw^. ^' u *^'*' ^^ lessen the quantity, of gas procurable from any given coal- J^r tTthllt;^^^^^^^^^ "^^^"'^ ^^^ '- P^^P-- «^«^<^ ^-y« ^' '-^aTned We have previously remarked, that too high a temperature ought to be avoided in th« Srh^ ;r!i1 '?^-^"^ ""^'^r ^^^ ^^^ very important reasons. Che Lt place he^^^^ car buretted hydrogen or olefiant gas is decomposed at a white heat, or even under thZ ^rbon th''"°'''''.r r^'^^- f^rburetted hydrogen, and the production of charcoaHJ carbon, thus greatly diminishmg the value of the gas as an illuminating ngent The second reason is still more conclusive. All coals contain iron pyrites, which at a low to a B^ iil T7TV"'' P^«J«,f Ph^'-.^t of iron and free sul^Lr ;lhe lattoi uniting to a portion of the hydrogen of the coal passes off, and is found in the gas in the rfiape of sulphuretted hydrogen, leaving the protJsulphuret of iron fn t^he Retort ohnrlfTf ' ^' ^«°^^°^t>rV^' "/•T^'^^^S «^ '""^^ ^« mentioned that this protos^l- phuret of iron was resolved by a high and long sustained heat into metaUic iron which remained m the coke, and into the bisulphuret of carbon, which escaued Now tl,. application of a high heat in gas makingLs exactly the same etcfas fn coke^^^^^^^^^^ and produces in both cases bisiUphuret of carbon, which, mixing with the coalX can never afterwards be removed. It consequently remainL in th! gas, and when^xis^s burnt m the ordinary way, gives rise to the production of sulphuric acid or oH of vitriol; and this, a though generated by most of the common gai of our street i^ an mfinitesimal quantity, is nevertheless found sufficient, in a few years, to attack and destroy the binding and paper of the books in our public librarie^^an?corrode articles liZ-^' 'r'^' f'"'"' "' ?^f' Th^V">P<>^'t-"t fact has not received a proper simre of consideration from our best gas engineers until within the last few moiths; and hence .riil i^ ^^'''T ^ .^^'^^.^^ ?" ^<^^ ^™i«h books completely discoloured and rotted through a great portion of each page, though in a few years all further traces of this mischievous effect of gas will have vanished. Having thus far commented on the production of coal-gas, we next pass to th« ^mination of the processes emploj^-ed in rendering it pure and fit for the uies to which It IS applied in common hfe. The first process is that of condensation, by wh ch rarl V the whole of the vapours, properiy so termed, are condensed and separatod from the per^ manently elastic gases. l3y this means, tar. water, naplitha, carbonate, muriate! and hydrosulphurate of ammonia, are removed from the ga^the only impurities of wWch now are carbonate of ammonia, carbonic acid, and sulphuretted h/drog1^n. Water alone will remove all three of these impurities ; but its action is weal^ and chiefly exercised upon the fii^t Hence, although usefully employed for attracting carbonat^Tf ammonia (as exemphfied m Lowe's scrubber, it is not used by gas engineers of the present dav with a view to total purification, this being soughti? in thi supW affinity olfml* after the ammonia has been arrested by other means. Coal-gas, after condeLtio^ usually contains about 2 per cent, of carbonic acid, and 1 per cent of sulSetted hydrogen ; but these vary, of course, with the nature of the coal, and also as we have rtated above with the dryness of the coal, which has much to do with the production of carbonic acid. These proportions may, however, be regarded as a fair average of New- castle coal-gas, and would justify the consumption of about 40 lbs. of lime for ev!^ 10,000 cubic feet of ^as ; a quantity which, although far below the propor i^ ex^nde'S m common practice IS really very near the consumption of lime carried out at the Wes^ mmster station of the Chartered Gas Company, by Mr. R J. Evans, during a long course of carefully conducted experiments, and ought, therefore, to bTkept if view J an ultimatum by gas engmeers. Where much more lime than is found in(fi8pensable to good purification, there is reason to suspect either that the coal is damp, or that it con- tains more than an average quantity of sulphur. The amount of sulphS- in good New- eastle coal is as nearly as possible 1 per cent, by weight, and in some of the cLiel c^ PITCOAL, COKING OF. 441 ^1: it is even less ; thus Boghead Cannel, for example, has barely one-half per cent., or 64 of sulphur on an average. How necessary, then, is it that every gas engineer should Se Twe to'determine the quantity of sulph'ur existing in coal! but even th^^^^^^^^o^* other knowledge, is worthfess ani deceptive Sulphur seems to !>; Pf^^^^^^VTbtui two states; the one and most frequent is that m which it is umted to iron ^bisul- phuret of iron or pyrites ; the other is in a doubtful state of combmation, but probably Ft eists conjoined to the bitmninous elements of the coal in the stato of sulphur Jo theTas maker this difference is very important, as in the former case, one-half only of the total sulphur would pass away with the gas and contaminate it, whereas m the second, the whole would be carried to the purify mg vessels; consequently^ in deter^ Sg the amount of sulphur in coal, a gas engineer must ascertain first how much Xhur the pure coal contains, and next how much sulphur remains in an eqmvalent of the coke of such coal ; after which the latter must be deducted from the f^rmey to get at the sulphur contamination of the coal, when its value for gas purposes is sought *^Th\t\Cinf detailed explanation will furnish the gas engineer with a means by which coal ma| be analyze(t with a view to the ob ect in question. Having carefiJly Teduced a VrLmpleof the coal to a very fine powder, mix 100 grains of this powder ^TsO grains of pure and dry carbonate of soda ; after which place the mixture m a dear iron 7id e, aSd roast the whole over a brisk fire, at a good red heat for several minutes, so as to burn off the whole of the coal, or nearly so; then remove the ladle from the fire and when it is cold, add 50 grains of pure and powdered nitre mixing to well wTt'h the residue of the coal and carbonate of soda; after which, place the ladle agai^ on the fire and keep it red hot for a few minutes, wjien it must be agam removeTsuffered to cool, and its soluble contents washed out with water and thrown on a mter. To the filtered liquor an excess of pure nitric acid must be added, and then a solution of nitrate of Lryta dropped in until aU precipitation ceases ;-b«n the sulphate of baryta, thus formed may be allowed to settle, or be thrown on a counterpoise filter, washed, dried, and weighed. Its eqmvalent, or 117 grains, indi "HavinlTliu: dStd the quantity of sulphur in the coal, 100 grains more of «!• powdered coal are to be taken Ind placed in an earthen • The coke being perfectly freed from all fuliginous and volatile matter*! hv » r»ln;n-f:«- of upwards of 40 hours, is cooled down to n.^erale ignition by~ ?n\hetrper^ and sliding up the doors, which had been partially closed during the la ler nart XS process It is now observed to form prismatic concretions, somUha^e fcohii^ mass of basalt These are loosened by iron bars, liAed out upon hovels funi^hS^ with long iron shanks, which are poised upon swing chains with hooked ends and t^ umps are thrown upon the pavement, to be exlin|uished by sprSgTat'er unon oCfn '/• "'''^f ^ watering-can; or, they might be 'transfer e? into a iaree chest of sheet-iron set on wheels, and then covered up! Good coals thus treated vipW SO^per cent, of an excellent compact glistening coke; 'weighing about 14 cwt. per' c'h'aU »nJ!ln.\'''' ^^■T!t^ !" coking in the ordinary ovens is usually reckoned at 25 per cent • and coal, which thus loses one fourth in weight, sains one fourth in bulk ' joy^tTrLably^sSoThe^Th/^"'" ^"'^^^^' ^^ rightly-constructed coke ovens, se.m to en If f/J^ '\^ ti^^ '^-7^ f ^^^ ^ '"'''■'""^ principles detected in wood-tar by Reichenbach 1 IS a dark.blue solid substance, somewhat like indigo, assumes a metallic fie^lustr^^^^^^ f. ct.on, and varies m tint from copper to golden, if is void of taste and smel? not vola lile ; carbonizes at a high heat without emitting an ammoniacal smeH "s sS or ralh.; very dilfusible in water; gives a green solution with a cast of crSi irsuloLnvljH with a cast of red blue, in muriatic acid, and with a cast of aurora red/inace^acT^ ^o^tmordantf'" '' ''" ^ '''' '^"^ "P^" ^^'^^'^ ''' ^««- good^ with Un a'd'alu" PLASTER; S^e Mortar. PLASTER OF PARIS ; see Gvpsum. for\omnf as ft will hn J !lT *^' 1'' ^"u* ^' T^^^ ^^^^^^ «*-^^«^^« ''« ^^e vessel used and drv tL ' L lu "^y* ^""^ ^l^""^ ^^"^ ^^^'^ ^«^ « «bort time ; then withdraw them, ?l?oo^ *''^^''^,^^^^^' continue this until all the articles have been treated h! ^IntTvf'"?''"^' then introduce into the hartshorn water clearwoolLn ra^^^^^^ theTilter"" TU^T'"! "^^^^ i^'T't^' "^*^^ ^^^^^ ^^^ *^«-' -^ "- them for poKg dool Whe? hf«?i^' '^"J'f '"^'^"°r ^?^ .^^^"°^°^ ^''^' «°^ b^^«« handle? of roorf Tsoft IP JvTI t^P^l^^^/^V'^es are perfectly dry, they must be carefully rubbed with ment of Inv J^A '^''^\''^' ^^'^^^°^ ^ "^^^"^°^ ^""^ "^"^^ preferable to the empToy- ^^siWer^IJH^^V ri^^'T^ mercury as mercury has the eflfect of rende^rUig The^vJ^nJf.t^^^^^V^^r^f''*''^^"^ ^ ^^^^-« the copper and XtJ^ct Z town of the metals. The mgot thus prepared is brought to the plating furnace The furnace has an iron door with a small hole to look through ; it if fed ^S'coke PLATED MANUFACTURE. 445 laid upon a grate at a level with the bottom of the - ^^^.^^Ve P^^^^^^^^ "eT- diately upon the cokes, the door is shut, and the P^^^Jd'' D^ n Ah^^^^^ of the silver gtant when the proper soldering temperature is attained. J^^^^fJ^^^^^^^^tact with the and copper, the surface of the former is seen to be ^^^awn into intimate com fattr. ^aSd this species of Hvetting is the signal - removing t^e compound bar i^^^^^^^ from the furnace. Were it to remain a very little longer, the Jil> er wo alloyed with the copper, and the plating be thus completely spoiled Tb^^f hes»«^^^ fac^CcLplished here by the formation of a fihn of true silver-solder at the surfaces of ^^hfineot is next cleaned, and rolled to the proper thinness between cylinders as de- scrM umler Mint; being in its progress of lamination frequently annealed on a srn^l gcrioeu uuuci "* » Aftprthe last annealing, the sheets are immersed in hot dilute TuIpt^raad'Tni^cot^e"^^^^ fini Calais sand ; they are then ready to be fashioned '"V" ''Tii'Jnt onnnpT'wire the «»ilver is first formed into a tubular shape, with one edge pro:. : Jt^n^. s "^ro"^^^^^^ ^»--^ a redhot copper cylinder being somewhat ectmg s^^?*^ y °Jf ' ,"L_, ' closely pressed together with a steel burnisher, whereby w Jprfi'rmW unilei The tube,^ l^^^^^^^ cleaned inside, and put on the prop- they get firmly un led. 1 he tub i ,^ .^ ^^^^ ^ ^.^^^^ ^^^^ .^^ Vu^Zl is torved at hrextrL^^^^ of the klter, so that the silver edges, being worked 1 \he c^meTJrcK>ve, m^^^^^^^ the air from the surface of the rod. The compound TvUnder is now heS redhot, and rubbed briskly over with the steel burnisher in a Ion- ^ndinaldire^^ion whereby the two metals get firmly united, and form a solid rod ready fo Sf drawaTn o wke of any requisite fineness and form ; as flat, half-round, fluted, or ■^ rnrmriincTs accordin- to the figure of the hole in the draw-plale. Such wire is mu^n ITs 5 fT S bre'd-^^^^^^^^ -"ffers, and articles combining elegance with ilthtnt's and economy. The wire must be annealed from lime to lime during ihe draw ;«'« on/1 finnllv cleaned, like the plates, with dilute acid. ^ , , , Xmeriy the tSt sh^ vessels of plated metal were all fashioned b>' the ham me^ but every one of simple form is now made in dies struck with a drop-hammer oi Stamp. Some manufacturers employ 8 or 10 drop machines. Aq. 1135. & 1136. are two views of the stamp ; a is a large stone, the moremassythe better ; b, the anvil on which the die e is secured by four screws, as shown in the ground plan,^^. 1137. Injig, 1136., a a are two upright square prisms, set diagonally with the lis? Ill i n angles opposed to each other ; between whieh the ha™?" "''^XlmeHsSffd K means of nicely fitted angular grooves orreeesses m its s.de^ .^helmmmer is raise j pulling the rope/, which passes over the pulley c, and is I'^f*"/™"* '"f !?, ?„» and according to tEel npulse Squired. Vessels which are less in ^J'^^f ?* J^^rTai °d bottom tLn in theLddle,S.ust either be raised by *« ^t"""?" 7i^Eed»P»" *« by a hand hammer. ThedieUusuallymadeofca«( steel Whenit ifl placea upu li 446 PLATED MANUFACTURE. anyfl, and the plated metal is cut into pieces of prooer mzp fh« fftT% /xf *t,« Ai^ : At. surrounded wi£ a lute made of oil anlclay, forC fnlh^'tt^ abSvf itel^^a^e • tl the cavity ,8 filled with melted lead. The under face of the stamp^mmmer has a pSte of iron called t}\e Itcker-up fitted mto it, about the area of the die^ Whenever the lead has become solid the hammer is raised to a certain height, and droppenown uDonTt • and as the under face of the licker-up is made rough like a raso if^rmW^Si^ * ' the lead so as to Hft it afterwards wfth the hammfr. iSe^aL^d metnsVowXed over the die, and the hammer mounted with its lead is let Lu repeatedly uZ VtiU the impression on the njetal is complete. If the vessel to be struck be Tanv con- siderable depth two or three dies may be used, of progressive sizes in succe^ioiT^ But It occasionally happens that when the vessel has a loi^ conical neck, rrcoTe mnsf be had to an auxiliary operation, called puru:hinr^. See ^e embossing puncher/?^! 138 These are made of cast steel, with their hollows turned out in the lathe. T^Viec^l ^6 are of lead. TJe punching is performed by a series of these tools, of differed Bizes, beginning with the largest, and ending with the least By this means a hoTw cone, 3 or 4 inches deep, and an inch diameter, may be raised out of a flat platl These punches are struck with a hand hammer also, for smaU articles of too ^eat delicacy fof the drop. Indeed it frequently happens that one part of an artide is executed by the stamp and another by the hand. f w an anicie is Cylindncal and conical vessels are mostly formed by bending and soldenng. The bcndms: is performed on blocks of wood, with wooden mallets ; but the machine so much used by the tin-smiths, to form their tubes and cylindric vessels (see the end section """ ' /g«.1139andll40),raightbe employed with advantage! This consists of 3 iron rollers fixed in an iron frame, a, b, c, are the three cylinders, and a, b, c, d, the riband or sheet of metal passed through them to receive the cvlindrical or conical curvature. The upper roller a can be raised or lowered at pleasure, in order to modify the diameter of the tube ; and when one end of the roller is higher than the other, the conical curvature is given. The edges of the plated cylinders or cones are soldered with an alloy composed of silver and brass. An alloy of silver and copper IS somewhat more fusible; but that of brass and silver answers best for plated meial the brass being in very small proportion, lest the color of the plate be aft'ected Calcined borax mixed with sandiver (the salt skimmed from the pots of crown glass) is used alone with the aUoy, in the act of soldering. The seam of the r-iated metal being smeared with that saline mixture made into a pap with water, and the bils of laminated solder, cut small with scissors, laid on, the seam is exposed to the flame of an oil blowpipe, or to that of charcoal urged by bellows in a little for^e-hearth, till the solder melts and flows evenly along the junction. The use of the sandiver seems to be, to prevent the iron wire that binds the plated metal tube from being soldered to it. Mouldings are sometimes formed upon the edges of vessels, which are not merely ornamental, but give strength and stifl*ness. These are fashioned by an instrument called a 5irage, represented in /g5. 1141 and 1142. The part a lifts up by a joint, and the metal lo he swaged is placed between the dies, as shown in the figures ; the tail b being held in the jaws of a vice, while the shear-shaped hammer rests upon it. By striking on the head a, whUe the metal plate is shifted successively forwards, the beadine IS formed In ^g. 1141 the tooth a is a guide to regulate the distance between the bead and the edge. A similar efi'ect is produced of late years in a neater and more expe- 1141 rrn ^^** ^^^^ PLATINUM MOHR. 447 ditious manner by the rollers, ^g». 1142, 1143. Fig. 1145 is a section to show the form of the bead. The two wheels a, a. Jig. 1143 are placed upon axes, two of which are furnished with toothed pinions in their middle j the lower one, being turned by the silver f^^J' J^^rf g^ ^^rface spekily worn ofl", and thus assumed a brassy look. The that the sunk part of ^^^J^ die should be siee^ generally emploved to form these silver or- •Tame^tr ¥hf ;n:rdVstiro"S;:J SSTg^s filled ^ith soft solder, and then bent into the requisite form. ^^^y ^ade in a die by the stamp, as weU as the The base f ^^^^^J^^f »';'„^^ J/^^^^^^ and the tubular stem or pillar. The dif- neck, the dish part of th^ n*^« « /oft and others with hard solder. The branches of whUe the plate is still Bat, and fixed b, burnishing w.th great pressure over « hot "^t JsJ'fiih ^^"'grSiven by bumishing-tools of bloodstone, fix«i in shee.- ""^^r^i:: rir^tS ^St'v^tt ^m^ with advantage by the deHcU 1 Jfi was 338 889/ but the vilue of the plated goods is not given in the tables of lev- ^e M pS' the greyest manufacturer of plated goods in P^MSL^^n ft;„« ZsbusfnessU monopolized by the capital), who makes to the value of , 00,000 fran« mis Dusmess u "'"•' l~ ooo^kid, he savs, is the whole internal consumpUon of the EtL7om"£thattheik^KsumVtlo^^ '^'^^ri^trtoJ^r^ ",^eT^v:r?isti:x„„n fene.3 eUhTampsTbu'r ^X P™\tSr„A wocHoulds in^t^^^^^^^^^^ lathe ^c. Lu ^^.r^ f h3r'strcu^"So":j,rdiSrent"s^i:s^^^^^^^^^^ ^PLATINUM MOHR. This interesting preparation, which so rapidly oxidizes alco- hof^JaSa™ by what has bercalled in ehem stry the ca^^^^^^^^^^ action, is most easily prepared by the fol owing Pro^css of M. f^«,^^\^J '^^^^^^^^ powder of potash-chiarure or ammonia-chlorure of platinum i. to f ^J^^^^^^^f^XJ? LThu He aid io^f^:^:^:!,^ t\lte wated ktt^with^Sfu^^^ S ardXYwi^h wat *^r fin^enl^if ttis powder depends upon that of the S^Une po.^e^/em^^^^^^ make it; so that if these ^t, ^^'^^^^l^T " ^Xm^i SfplaWm mohr wifl be also very fine, and proportionally powerfiil as a chemical ""^The following easy method of preparing igniferous ^^ack platinum, P^^^^^^^^^^ thirty years aL'o by M Descotil, has been recently recommended by M. Dobereiner .-■ ^Md^Dlatina ore with double its weight of zinc, reduce the allojr to powder, and treat it Ct with dilute sulphuric acid, and next with dilute nitric a«d, to oxidize and Sssolve outlll the z!nc, wlSch, contrary to one's expectations, is somewhat difficult to do even at a boS^^^^^^ The insoluble black-gray powder con^ins some osmmret of iridiui^ united w^ith tiie crude platinum. Tliis compound acts like ."°^P^^ Pl^^V^^* blaclTafS'r^t has been purified by digestion in potash Y,^rArmL^°L7dt^1he Its oxidizing power is so great, as to transform not only the /ormic acid into the carbonic, and alcohol into vinegar, but even some osmic acid, from the metallic osmium. The ^bove powder explodes by heat like gunpowder. When the platinaJoAr prepared by means of zinc is moistened Y;^^ al.«*^*>^ ^^^ comes incan/escent, and emits osmic acid; but if it be mixed with alcoho into a past^ and spread upon a watch-glass, nothing but acetic acid will be disengaged ; affording an elegant means of diffusing the odour of vinegar m an apartment bee ^^'^J-ff, ., Platinizing by the moUt way. Manufacturing and operative chemists wiU find it exfeedingly valuable in order'^to produce a covering of platma for Jhen- copper A^ vessels, fhe experiment succeeds ^est when we make use of a dilute s^^V^t^^" ^fJ^J Sle chloride o^f soda and platina. Three immersions suffice ; between ea«h mimersi^^ it is necessary to dry the surface with fine linen, rubbing rather briskly, after which it -"■'^--•iWi 448 PLATINUM. PLATINUM. 449 .toof T. • V^ A T^^ ?f ^ grayish-white color, rcsembJin? in a good measure Dolished steel. It IS harder thah silver, and of about double its density, UToTlT^iirJ^v^ Native Ptatmum.-U the nataral state it is never pure, bein? alloved with sev^ml ^o 1 ^^1°^ ""^ .^^^ ^"^'"^ °^ "''^^^^ platinum is generally a grayish-white like tarnhhpd 2r, orT ' T"'''" "^i'^^ T^^ ^™^"^ ^"-^ «^«^ fi"^d with^rVhy and feV u4ous mal^ ters, or sometimes with small grains of black oxyde of iron, adherinrto the surface of the platmum grains Their specific gravity is also much lower than that of for4d Dur« platinum ; varying from 15 in the small particles to 18-94 in M W,,mh^w.i i ^ ^^ men This relative lightness is owing to'the pre^enVe of il^'c^f;^^ aidTh^o'me: ^ndlr" Jum^*''' ""' lately discovered metalUc constituents, piXm^oslm^h^^^^ Its main localities in the New Continent, are in the three following districts — 1. At Choco, in the neighborhood of Barbacoas, and generally Sn the coa-ts of th« fSS^hf^^J,''? **" the western .lopes of the Cordillera of the A^e., between^^^^^^ and the 6th degrees of north latitude. The gold-washin'-s that fnmAh TJ f J^ I- are those of Condoto, in the province of Novita • Those of w/p"/ t P»atinum, Santa Lucia of the Vavine of Iro" and Cto, betw:eVNovi ta and TaSdJ" Th?.?! ^Ueof gold and platinum grains is founrin^lluvial Vou^taf a dipth ^^^^ amal..«H-?n f ''T^^'? ^'°'" ^^^ -^^^^^"""^ ^^ P^^^'^"? ^''^ »»»« hand, and also by amalgamation ; formerly, when ,t was imagined that platinum might be used to debaS go d, the grams of lhe,former metal were thrown into the rivers, through wikh mistaken opinion an immense quantity of it was lost. misiaKeu 2. Platinum grains are found in Brazil, but always in the alluvial land*! thnf /.nnfo:« From' tC o7Sc!," ^'r ^' ""^'^^T, The ore'of thistum^t soteU'at diff T^iK 1 r ^K • ^^. 'f '" ^'■^'"'' ^^'""^ '^^°» t« ^^ fragments of a spongy substance The whole of the particles are nearly globular, exhibiting a surface formed of small bSlTant ^'''^"^'^^'^^ «^-?Jy ^«^-i"g together, whose interstices .^eclean^nd^^^^^^^ This platinum includes many small particles of gold, but none of the ma^nPtl^ irnn sand or of the small zircons which accompany the Peruvian ore? I is mixed^ w^ smaU grams of native palladium, which may be recognised by their fibrous orrrdktedTruclure and particularly by their chemical characters. ^auiaieu siruciure, 3. Platinum grains are found in Hayti, or Saint Domingo, in the sand of the river Jacky, near the mountains of Sibao. Like those of Choco thev are n sm^lt >.rnr f grains as if polished by friction. The sand containing therisquarrzoseandTer^^^^^^^^^ This native platinum contains, like that of Choco, chromium rnnn^r^ll- •""•?• rhcdiu., palladia., and probably Utaniu.. VaSq'„eIirc3 finT"i g^Td'Ttiillg I^ Platinum has been discovered lately in the Ruscsian f#»rritAi.,-oo ;„ .i, -r of Kuschwa 230werstsfrom Ekateriebo'urg^Td'ccnC^m?^ which seems to be analogous with that of South America geoio^^icai position These auriferous sands are, indeed, almost all superficial; they cover an areillaceon, soil . and include, along with gold and platinum,debrisof doleritc (aS of g"fi^^^^^^^^^^^ protoxyde of iron, grains of corundum, &c. The platinum -rains are not \sn fln^^! i k ^' from Choco, but they are thicker ; they have less'brilCcrand Tore of " feaden hu? This platinum, by M. Laug.er's analysis, is similar in purity to that of Choco but the leaden-gray grains, which were taken for a mixture of osmium and iridium, a^e merely an alloy of platinum, containing 25 per cent, of these metals merely an The mines of Brazil, Columbia, and Saint Domingo furnish altogether only about 400 kilos, ofplatmum ore per annum; but those of Russia produce a£,ve 1800 kilo^ The latter were discovered in 1822, and were first worked in 1824. They are all situated in he Ural mountains. The ore is disseminated in an argillaceous sand, of a greenish-graY color resulting from the disintegration of the surrounding rocks, and constitutes from 1 to 3 parts in 4000 of the sand. Occasionally it has been found in lumps weighing 8 kilo- erammes (16 1bs. !), but it generally occurs in blackish angular grains, which contain 70 per cent, of platinum, and 3 to 5 of iridium. The ore of Goro-Blagodatz is in small flattened grains, which contain 88 per cent, of this precious metal. The osmiure of iri- dium is found upon a great many points of the Urals, throughout a space of 140 leagues, being a product accessor^' to the gold washings. 32 kilogrammes of osmiure are collected there annually, which contain upon an average 2 per cent, of platinum. M. Vauqueiin found nearly ten per cent, of platinum in an ore of argentiferous cop- per which was transmitted to him as coming from Guadalcanal in Spain. This would be thc*only example of platinum existing in a rock, and in a vein. As the same thing has not acrain been met with, even in other specimens from Guadalcanal, we must delay drawing geological inferences, till a new example has confirmed the authenticity of Platinum has been known in Europe only since 1748, though it was noticed by Ulloa in 1741. It was compared at first to gold; and was, in fact, brought into the market under the name of white gold. The term platinum, however, is derived from the Spanish word plata, silver, on account of its resemblance in color to that metal. The whole of the platinum ore from the Urals is sent to St. Petersburg, where it is treated by the following simple process :— ^, - . • • r One part of the ore is put in open platina vessels, capable of containing from 6 to 8 lbs., along with 3 parts of muriatic acid at 25" B. and 1 part^of nitric acid at 40". Thirty of these vessels are placed upon a sand-bath covered with a glazed dome with moveable panes, which is surmounted by a ventilating chimney to carry the vapors out of the laboratory. Heat is applied for 8 or 10 hours, till no more red vapors appear; a proof that the whole nitric acid is decomposed, though some of the muriatic remains. After settling, the supernatant liquid is decanted off into large cylindrical glass vessels, the residuum is washed, and the washing is also decanted off. A fresh quantity of nitro-muriatic acid is now poured upon the residuum. This treatment is repeat- ed till the whole solid matter has eventually disappeared. The ore requires for solution from 10 to 15 times its weight of nitro-muriatic acid, according to the size of iU grains. * ^i. • -j- The solutions thus made are all acid; a circumstance essential to prevent the indium from precipitating with the platinum, by the water of ammonia, which is next added. The deposite being allowed to form, the mother waters are poured off, the precipitate is washed with cold water, dried, and calcined in crucibles of platinum. The mother-waters and the washings are afterwards treated separately. The first oeing concentrated to one twelfth of their bulk in glass retorts, on cooling they let fall the iridium in the state of an ammoniacal chloride, constituting a dark-puqile powder, occasionally crvstallized in regular octahedrons. The washings are evaporated to dryness in porcelain vessels ; the residuum is calcined and treated like fresh ore ; but the platinum it aflords needs a second purification. For agfflomerating the platinum, the spongy mass is pounded in bronze mortars; the powder is passed through a fine sieve, and put into a cylinder of the intended size of the ingot. The cylinder is fitted with a rammer, which is forced in by a coining press, till the powder be much condensed. It is then turned out of the mould, and baked 36 hours in a porcelain kiln, after which it may be readily forged, if it be pure, and may receive any desired form from the hammer. It contracts in volume from l-6th to l-5th during the calcination. The cost of the manufacture of platinum is fixed by the administration at 32 francs the Russian pound ; but so great a sum is never expended upon it. For Dr. Wollaston's process, see Phil. Trans, 1829, Part I, Platinum furnishes most valuable vessels to both analytical and manufacturing chemists. It may be beat out into leaves of such thinness as to be blown about with the breath. This metal is applied to porcelain by two different processes; sometimes in a. rather coarse powder, applied by the brush, like gold, to form ornamental figures; sometimes in a state of extreme division, obtained by decomposing its muriatic solution, by means of an essential oil such as rosemary or lavender. In this case, it must be evenly spread over the whole ground. Both modes of application give rise to a steely lustre. The properties possessed in common by gold and platinum, have several times given occasion to fraudulent admixtures, which have deceived the assayers, M. Vauqueiin having executed a series of experiments to elucidate this subject, drew the following con- clusions : — Vol, XL 8 M ii '•'t-tv 450 PLUMBAGO. If the platinum do not exced 30 or 40 parts in the thousand of the alloy, the gold does not retain any of it when the parting is made with nitric acid in the usual way ; and Avhen the proportion of platinum is greater, the fraud becomes manifest; Jst by the higher temperature required to pass it through the cupel, and to form a round button ; 2. by the absence of the lightning, fulguration, or coruscation; 3. by the dull while color of the button and its crystallized surface ; 4. by the straw-yellow color which platinum communicates to the aquafortis in the parting; 5. by the straw-yellow color, bordering on white, of the comet, after it is annealed. If the platinum amounts to one fourth of the gold, we must add to the alloy at least 3 times its weight of fine silver, laminate it very thin, anneal somewhat strongly, boil it half an hour in the first aquafortis, and at least a quarter of an hour in the second, in order that the acid may dissolve the whole of the platinum. Were it required to determine exactly the proportions of platinum contained in an alloy of copper, silver, gold, and platinum, the amount of the copper may be found In the first place by cupellation, then the respective quantities of the three other metals may be learned by a process founded, 1. upon the property possessed by sulphuric acid of dissolving silver without affecting gold or platinum ; and, 2. upon the property of pla- tinum being soluble in the nitric acid, when it is alloyed with a certain quantity of gold and silver. According to Boussingault, the annual product of platinum in America does not exceed 8| cwts. At Nis»?hne-Tagilsk, in 1824, a lump of native platinum weighing fully 10 lbs. was found ; and in 1830, another lump, of nearly double size, which weighed 35| Prus* fiian marcs; fuUy 18 lbs. avoirdupois. PRODUCTION OF PLATINUM IN THE URAL. From 1822 to 1827 inclusively, 52 puds* and 22* pounds. 1828 94 1829 78 31 J 1830 105 1 1831 to 1833 348 16 AwALTSEs of the Plvtinum Ores of the Urals, and of that from Barbacoas on the Pacific, between the 2d and Hth degrees of northern latitude. From Nischne-Tagilsk. Berzcliiis. Uoroblagodat. BarbacoM. Osann. Berzelius. Magnetic. Not Maapnetic. Platinum 73-58 78-94 83-07 86-50 84-30 Iridium - 2-35 4-97 1-91 , _ 1-46 Rhodium 1-15 0-86 0-59 1-15 3-46 Palladium 0-30 0-28 0-26 MO 1-06 Iron 12-98 11-04 10-79 8-32 5-31 Copper - 5-20 0-70 1-30 0-45 0-74 Undissolved ^ Osmium and > Iridium ^ 2-30 1-96 1-80 1-40 — Osmium ^_ 1-03 Quartz - Lime - ■"" ^a^m — — 0-60 0-12 97-86 98-75 99-72 98-92 98-08 PLUMBAGO. See Graphite, for its mineralogical and chemical characters. The mountain at Borrowdale, in which the black-lead is mined, is 2000 feet high, and the en- trance to the mine is 1000 feet below its summit. This valuable mineral became so com- mon a subject of robbery about a century ago, as to have enriched, it was said, a ereat many persons liymg m the neighborhood. Even the guard stationed over it by the pro- prietors was of little avail against men infuriated with the loveof plunder ; since in those days a body of miners broke into the mine by main force, and held possession of it for a considerable time. The treasure is now protected by a strong building, consisting of four rooms upon the ground floor; and immediately under one of them is the openin?, secured by a trap- door, through which alone workmen can enter the interior of the mountain. In thw anartment, called the dressing-room, the miners change their ordinary clothes for their • One pud =40 Russian pounde, = 69,956 Pruwian marcs (See Silvek) ; 1 pound - 96 lolotnito PORCELAIN. 451 worKing dress, as they come in, and afler their six hours' post or journey, they again change their dress, under the superintendence of the steward, before they are suffered to go out. In the innermost of the four rooms, two men are seated at a large table, sorting and dressing the plumbago, who are locked in while at work, and watched by the steward from an adjoining room, who is armed with two loaded blunderbusses. Such formidable apparatus of security is deemed requisite to check the pilfering spirit of the Cumberland mountaineers. The cleansed black-lead is packed up into strong casks, which hold 1 cwt. each. These are all despatched to the warehouse of the proprietors in London, where the black-lead is sold monthly by auction, at a price of from 35s. to 45s. a pound. In some years, the net produce of the six weeks* annual working of the mine has, it is said, amounted to 30,000Z. or 40,000/. PLUSH (Panne, Peluche, Fr. ; Wollsammety Plmch, Germ.) is a textile fabric, having a sort of velvet nap or shag upon one side. It is composed regularly of a woof of a sinde woollen thread, and a two-fold warp, the one, wool of two threads twisted, the other, goat's or camel's hair. There are also several sorts of plush made entirely of worsted. It is manufactured, like velvet, in a loom with three treadles ; two of which separate and depress the woollen warp, and the third raises the hair-warp, whereupon the weaver, throwing the shuttle, passes the woof between the woollen and hair warp ; afterwards, laying a brass broach or needle under that of the hair, he cuts it with a knife (see Fustian) destined for that use, running its fine slender point alons: in the hollow of the guide-broach, to the end of a piece extended upon a table. Thus the surface of the plush receives its velvety appearance. This stuff is also made of cotton and silk. POINT NET is a style of lace formerly much in vogue, but rtbw superseded by the bobbin-net manufacture. 1X)LYCHR0MATE {Polychromate, or chrysammic acid\ a new compound from which a variety of colours may be prepared. Chrysamraic acid, if such be the acid here alluded to, has been known hitherto only to theehemist as the result of the action of nitric acid upon powdered aloes. Obtained by this process, chrysammic acid appears in golden crystals. The salts of compounds of this acid are remarkable for their brilliancy of colour ; but their application in the arts is perfectly new. . , , PORCELAIN, is the finest kind of pottery-ware. It is considered under that title. The articles in the Exhibition under the head Statuary Porcelain, including Parian, Carrara, (fee, are produced by "casting." As the most direct method of illustrating this process, let us suppose the object under view to be a figure or group, and this we will assume to be 2 feet high in the model. The cl?iy, which is used in a semi-liquid state, about the consistency of cream, and called "slip,"*^is poured into the moulds forming the va- rious parts of the subject (sometimes as many as fifty): the shrinking that occurs before these casts can be taken out of the mould, which is caused by the absorbent nature of the plaster of which the mould is composed, is equal to a reduction of one inch and a half in the height These casts are then put together by the "figure-maker," the seams (consequent upon the marks caused by the subdivisions of the moulds) are then carefully removed, and the whole worked upon to restore the cast to the same degree of finish as the original model. The work is then thoroughly dried, to be in a fit state for firing, as, if put in the oven while damp, the sudden contraction consequent upon the great degree of heat instantaneously applied would be very liable to cause it to crack; in the process it again suffers a further loss of one inch and a half by evaporation, and it is now but 1 foot 9 inches. Again in the "firing" of the bisque oven, its most severe ordeal, it is diminished 3 inches, and is then but 18 inches high, being 6 inches or one fourth less than the original. Now, as the contraction should equally affect every por- tion of the details of the work, in order to realize a faithful copy, and as added to this contingency are the risks in the oven of being " over-fired," by Avliich it would be melted into a mass, and of being "short-fired," by which its surface would be im- perfect, it is readily evident that a series of difficulties present themselves which require considerable practical experience successfully to meet The moulds are made of plaster of Paris, which, when properly prepared, has the property of absorbing water so effectually that the moisture is extracted from the clay, and the ware is enabled to leave the mould, or " deli ver " with care and rapidity. Prior to use the plaster (gypsum) is put into long troughs, having a fire running underneath them, hy which means the water is drawn off, and it remains in a state of soft powder; and if its own proportion of water be again added to it, it will immediately set into a firm compact body, which is the case when it is mixed to form the mould. The following are the degrees of temperature in which the different branches work : — 3M2 IT r. ,^^y|||^ 452 PORCELAIN. PORCELAIN. 453 II IP:., |l/v_-,.; 1*' "i. Plate-makers' hothouse Dish-makers' hothouse I^rinters' shop Throwers* hothouse 108® Fahr. 106 „ 90 98 fi The branches against which the temperature of the hothouse is placed, require that heat for drying their work and getting it oflF their moulds. The outer shops in which they work may be from five to ten degrees less. Variety of vases, garden pots, and articles of ordinary use. Ancient font^ from the original in Winchester Cathedral. The Portland jug. Lily of the valley jug. The acanthus garden vase. Fine porcelain. A vase of Etruscan form, with chased and burnished gold ornaments on a blue ground, decorated with floral wreaths enamelled, in colours, Ac, with pedestal 40 inches high. A variety of ornamental vases, chased and gilded with various designs and otherwise. Verulam bottles, ribbon wreath, and group of flowers, turquoise ribbon, and group of flowers ; and gold lattice. Large tripod for flower stand, blue ground decorated in chased and burnished gold. The Dove tazze and pedestal. The birds and embossments in solid gold, chased turquoise ground and floral wreath, npodtions for glazing earthenware.-The materials eo™Pri«ed »n ^^^.^^\'^^l dazes commonly used for china and earthenware, are Cornish stone, flmt, jtite lead^ llass whiting, L. These having been ground together in proper proportions to the fonltence of 'milk form the glaze. The process is eftected in \«2i!.^t.^3^Tbi « dippine-houses," (china and earthenware bemg kept separate) fatted up with tubes for the glaze, and stages for the reception of the ware when dipped, uix)n which it u dried afd heated, generally by means of a large iron stov;e or "cockle," from which iron ptpes extendiifg in various directions convey the heat throughout the whole extent of the " houses." Each dipper is provided with a tub of glaze, m which he imnaersea the bisque ware. We may note the results of practice and experience in imparting a facility and dexterity of handling so necessary to perfection m this process. The ware is held so that as small a portion as possible shall be covered by the fingers ; it is then plunged in the glaze, which by a dexterous jerk is made not only to cover the entu-e pied but at thi same time so disperses it, that an equal and level portion is disposed Sver the whole surface, which, being porous, imbibes and retains it 1 he ware is handed to the dipper by a boy, and another removes it when dipped to the drymg or hot- house." The glaze is opaque till fired, so that the design of pattern executed on the bisque is completely hid after dipping till they have been submitted to the glost fire. An able workman will dip about 700 plates m a day. In 1751 Dr Wale established a manufactory in Worcester, under the name of the « Worcester Porcelain Company," and to him appears to be due the idea of printing upon porcelain, the transferring of printed patterns to biscuit ware as usually adopted. From a magazine in the Museum of Practical Geology decorated with a portrait of Frederick the Great, the date ofthis process appears to be 17 57. , . , . ;, The original Worcester Company principally confined themselves to making blue and white wai'e in imitation of that of Nankin, and in producing copies of the Japanese ^^Cockwortly of Plymouth appears to have carried on the business of a potter in Worcester until 1783, when the manufactory passed into the possession of Mr. Thomaa Stone china differs from the "tender porcelain," as the English ware is termed, it bein<' a fused body ; the alkali of the clays employed being by the heat of the furnace made to combine "with the silica and alumina. Enamel colours are such as consist of metallic oxides combined with an alkaline flux, which, when exposed to a high tempera ture, forms a perfect glass. . . -^ • • j ^ When the ware leaves the hands of the painters, gildei-s, Ac, it is carried to a receir- ine-room in connexion with the "enamel-kilns." The firemen select the ware frona this room, according to the degree of heat they may require, and place it m that part of the kiln most likely to secure it The different articles are ranged upon stages con- structed of " slabs " or " bats " supported on props all made of fired clay. Tlie time of firing is from 6 to 7 hours according to the size of the kiln, and whether it contains auv articles of unusual size and hazard, in which case the heat is brought forward very gradually The ♦♦groimd-laymg" being executed with colours less fusible than those t n 'Hf^ 456 PORTER. employed by the painters, the ware so decorated is fired in separate kilns at a highei temperature, a level glossy surface being a great desideratum ; and as gold is often used m rehef upon the "grounds," it would be liable to sink and lose its lustre unless the under colour had received a greater degree of heat than is required by the gilding. The kilns are built of large fired clay slabs made expressly for the purpose. They are about 8 feet SIX inches wide, 7 feet 6 inches high, and 6 feet 6 inches long, with circular tops, Jia\ang flues beneath* and around them. The fire-places or "mouths" are at the sides, and the flames passing through the flues, encircle the kiln externally. Great care is taken to prevent the admission of smoke or flame into the body of the kilns, the fronts of which are closed with iron doors having in them small apertures, through which the firemen occasionally^ draw " trails" of colour made upon small pieces of ware, and thus ascertain to a certain extent the progress of the heat. This is a material assistance, but being drawn from one part only, still leaves a task requiring great care and nicety of judgment to manage successfully. Gold, if not sufliciently fired, will wipe off, and if over fired will not " burnish," and the gilding has to be repeated. Penthesilea, Queen of the Amazons, slam, supported hy Achilles, 2'hymhrean Apollo and Cassandra. Iris and Alcuraon. The class of work to which these examples belong may be ranked^under the head of Reproductive Art. The historical, mythical, and domestic events which they illustrate, form vivid and instructive records of the manners and cus- toms of the ancients. The original bases which have formed the material in this series are amougst the earliest memorials of Hellenic civilization. The date of their production extends from the second to the fifth century of the Christian era. The diversity and elegance of their forms bear conclusive evidence of the grace and beauty with which a refined and cultivated intelligence can mould the objects which minister to the humble and familiar purposes of household wants. Their application was chiefly to domestic requirements; and it being a custom con- nected with the right of burial to deposit within the sepulchre such objects as the deceased had most highly valued during life, the interment of a large number of these mortuary treasures, which so graphically illustrate Greek art and life, resulted. To this we owe the preservation of so interesting and numerous a series of these valuable mementos of archaic taste and skill. They are composed of red clay, the figure and ornamental com- position being executed on a dark liquid pigment, worked in quick-drying oils, and submitted to a considerable degree of heat, to secure eff^ectual adhesion. Amongst the earliest designs are placed these in which the black selhouette-like figures are painted upon the red or buff ground. These vases with the figures and ornaments in a red on a black ground mark the period when Greek art was at its zenith. In reference to the forms of these vases it may be instructive to remark that a careful analysis of the best examples in the British Museum proves that every curve is the seg- ment of a circle ; and it has been mathematically demonstrated that even in instances where the most irregular diversity of outline has been presented, that every curve has been circular and none elliptical. PORPHYRY, is a compound mineral or rock, composed essentially of a base of hornstone, interspersed with crj-stals of felspar. It frequently contams also quartz, mica, and hornblende. That most esteemed is the ancient porphyry of Egypt, with a ground of a fine red colour passing into purple, having snow-white crjstals of felspar imbedded in it. Most beautiful specimens of it are to be seen in the antique colossal statues in the British Museum. Porphyry occurs in Arran, and in Perthshire between Dalnacaidoch and Tummel brids:e. It is much used for making slabs, mullers, and mortars. PORTER is a malt liquor, so called from being the favorite beverage of the porters and workpeople of the metropolis and other large towns of the British empire ; it is char- acterized by its dark-brown color, its transparency, its moderately bitter taste, and pecu- liar aromatic flavor, which, along with its tonic and intoxicating qualities, make it be keenly relished by thirsty palates accustomed to its use. At first the essential distinction of porter arose from its wort being made with highly-kilned brown malt, while other kinds of beer and ale were brewed from a paler article ; but of late years, the taste of the public having run in favor of sweeter and lighter beverages, the actual porter is brewed with a less proportion of brown malt, is less strongly hopped, and not allowed to get hard by long keeping in huge ripening tuns. Some brewers color the porter with burnt sugar ; but in general the most respectable concentrate a quantity of their first and best wort to an extract, in an iron pan, and burn this into a coloring stuff, whereby they can lay claim to the merit of using nothing in their manufacture but malt and hops. The singular flavor of good London porter seems to proceed, in a great degree, from that of the old casks and fermenting tuns in which it is prepared. Though not much addicted to vinous potations of any kind, I feel warranted by long experience to opine, that the porter brewed by the eminent London houses, when drunk in moderation, is a far wholesomer beverage for the people than the Ihin acidulous wines of France and Germany. See Beer. POTASH. 457 PORTLAND CEMENT, is formed by calcining together limestone and some ar^l- laceous earth, the result being a mass which most rapidly absorbs a certain quantity of water, and then becomes solid as a hydrous silicate of lime. Tlie advantages oyer natural hydraulic limes consist generally in greater hardness and durability, ansmg from the mixture of material being more perfectly under command. Bricks cemented tocether by it bear a pressure on the outermost brick of 3 tons ; being a beam of cement. A block of this cement tested by the hydraulic press bore a pressure of PORTLAND STONE, is a fine compact oolite, so named from the island wheie it is quarried. It is a convenient but not a durable building stone. POTASH or POTASSA. (Potasse, Fr. ; Kali, Germ.) This substance was so named from beinff prepared for commercial purposes by evaporating in iron pots the lixivium of the ashes of wood fuel. In the crude state called potashes, it consists therefore, of such constituents of burned vegetables as are very soluble in water, and fixed in the fire. The potash salts of plants which originally contained vegetable acids, will be converted into carbonates, the sulphates will become sulphites, sulphurets, or even carbonates, accord- ing to the manner of incineration; the nitrates will be changed into pure carbonates, while the muriates or chlorides will remain unaltered. Should quicklime be added to the solution of the ashes, a corresponding portion of caustic potassa will be introduced into the product, with more or less lime, according to the care taken in decanting ofl the clear ley for evaporation. , , .», -i •» In America, where timber is in many places an incumbrance upon the sod, it » felled, piled up in pyramids, and burned, solely with a view t9 the manufacture of potashes. The ashes are put into wooden cisterns, having a plug at the bottom of one of the sides under a false bottom ; a moderate quantity of water is then poured on the mass, and some quicklime is stirred in. AAer standing for a few hours, so as to take up the soluble matter, the clear liquor is drawn oflT, evaporated to dryness in iron pots, and finally fused at a red heat into compact masses, which are gray on the outside, and pink-colored within. , . v ^v *-n tx,^ «.>>»1a Pearlash is prepared by calcining potashes upon a reverberatory hearth, till the whole oaiboaaceous matter, and the greater part of the sulphur, be dissipal^l : then lixiviatmg the mass, in a cistern having a false bottom covered with slrav, evaporating the clear lye to dryness in flat iron pai^ and stirring it towards the end into white lumpy granu- * 1 fil^d the best pink Canadian potashes, as imported in casks containing about 5 cwts., to contain pretty uniformly 60 per cent, of absolute potassa ; and the best pearlashes to contain 50 per cent.; the alkali in the former being nearly in a caustic state; in the latter, carbonated. j> t. rru^ ^^.^ All kinds of vegetables do not yield the same proportion of potassa Ihe more succulent the plan? the more does it afford ; for it is only in the juices that the vegetable salts reside, which are converted by incineration into alkaline matter. Herbaceous weeds are more productive of potash than the graminiferous species or shrubs, and these than trees- and for a like reason twigs and leaves are more productive than timl)er. But plants in all cases are richest in alkaline salt^ when they have arrived at maturity. The soil in which th«^y grow also influences the quantity of saline matter. The following Table exhibits the average product in potassa of several plants, accord- ing to the researches of Vauquelin, Pertuis, Kirwau, and De Saussure :— In 1000 parts. Pine or &r - Poplar Trefoil - - Beechwood- Oak - - - Boxwood - Willow Elm and Maple - Wlieat straw - Barb of oak twigs Potassa. I In 1000 parts. 0"45 i Thistles - 75 - 075 - l-4i - 1-53 . 2'26 - 2"8.'» 390 390 420 Flax stems Small rushes - Viiie shoots Barley straw - Dry beech bark Fern - T^arge rush Stalk of maize - Bean stalks Potassa. - 500 - 500 - 608 - 5 50 . 5-80 - 6-00 . 6-2G . 722 In 1000 parts. Potassa. Bastard chamomile iAtithe- mis cotula, L.) Sunflower stalks - • - Common nettle Vetch plant ... - Thistles in full growth • Dry straw of wheat before earing i7'5 Wormwood 20'0 1 Fumitory • 196 2000 2503 2750 35-37 4ro 730 79-0 Stalks of tobacco, potatos, chesnuts chesnut husks, broom, heath, furze, tansy, son-el, vine leaves, beet leaves, orach, and many other plants, abound in potash salt*. In Bur- eundv the well known cendres gr^velees are made by incinerating the lees of wine pressed into cakes, and dried in the sun ; the ashes contain fully 16 per cent, of potassa. The purification of pearlash is founded upon the fact of its being more soluble m water than the neutral salts which debase it. Upon any given quantity of that substance, in an iron pot, let one and a half times its weight of water be poured, and let a gentle heat be applied for a short time. When the whole has again cooled, the bottom will be encrusted with the salts, while a solution of nearly pure carbonate of potash will be found floatino- above, which may be drawn off clear by a syphon. The salts may be after- wards thrown upon a filter of gravel If this lye be diluted with 6 times its bulk of water, Vol. IL 3 N Ml: I i 458 POTASH. POTASSIUM. 459 mixed with as much slaked lime as there was pearlash employed, and the mixture be boiled for an hour, the potash will become caustic, by giving up its carbonic acid to the lime. If the clear settled lixivium be now syphoned off, and concentrated by boiling in a covered iron pan, till it assumes the appearance of oil, it will constitute the common caustic of the surgeon, the potassa fusa of the shops. But to obtain potassa chemically pure, recourse must be had to the bicarbonate, nitrate, or tartrate of potassa, salts which, when carefully crystallized, are exempt from any thing to render the potassa derived from them impure. The bicarbonate having been gently ignited in a silver basin, is to be dissolved in 6 times its weicht of water, and the solution is to be boiled for an hour, along with one pound of slaked lime for every pound of the bicarbonate used. The whole must be left to settle without contact of air. The supernataut ley is to be drawn off by a syphon, and evaporatetl in an iron or silver vessel provided with a small orifice in its close cover for the escape of the steam, till it assumes, as above, the appear- ance of oil, or till it be nearly redhot. Let the fused potassa be now poured out upon a bright plate of iron, cut mto pieces as soon as it concretes, and put up immediately in a botlle furnished with a well-ground stopper. It is hydrate of potassa, being composed of 1 atom of potassa 48, -|- 1 atom of water 9, = 57. A pure carbonate of potassa may be also prepared by fusing pure nitre in an earthen crucible, and projecting charcoal into it by small bits at a time, till it ceases to cause deflagration. Or a mixture of 10 parts of nitre and 1 of charcoal may be deflagrated in small successive portions in a redhot deep crucible. When a mixture of 2 parts of tartrate of potassa, or crystals of tartar, and 1 of nitre, is deflagrated, pure carbonate of potassa remams mixed with charcoal, which by lixiviation, and the agency of quick- lime, will afford a pure hydrate. Crystals of tartar calcined alone yield also a pure carbonate. Caustic potassa, as I have said, after being fused in a silver crucible at a red heat, retains 1 prime equivalent of water. Hence its composition in 100 parts is, potassium 70, oxygen 14, water 16. Anhydrous potassa, or the oxyde free from water, can be ob- tained only by the combustion of potassium in the open air. It is composed of 83| of netal, and 16f of oxygen. Berzelius's numbers arc, 8305 and 16-95. Caustic potassa may be crystallized ; but in general it occurs as a white brittle sub- stance of spec. grav. 1*708, which melts at a red heat, evaporates at a white heat, de- liquesces into a liquid in the air, and attracts carbonic acid; is soluble in water and alcohol, forms soft soaps with fat oils, and soapy-looking compounds with resins and wax ; dissolves sulphur, some metallic sulphurets, as those of antimony, arsenic, &.C., as also silica, alumina, and certain other bases; and decomposes animal textures, as hair, wool, silk, horn, skin, &ic. It should never be touched with the tongue or the fingers. The following Table exhibits the quantity oC Fused Potassa in 100 parts oC caustic ley, at the respective densities : — Sf. gr. Pot. in 100. Sp.gr. 1-46 Pot. in 100. I ! Sp. gr. Pot. in 10(i Sp. gr. Pot. in 100. 1 . Sp. gr. Pot.mHiO 1-58 53-06 42-31 1-34 32- 14 1-22 23-14 1-10 11-28 1.56 51-58 1-44 40-17 1-32 30-74 1-20 21-25 1-08 9-20 1-54 50-09 1-42 37-97 1-30 29-34 1-18 19-34 1-06 7-02 1-52 48-40 1-40 35-99 1-28 27-86 1-16 17-40 104 4-77 1-50 46-45 1-38 34-74 1-26 26-34 1-14 15-38 1-02 244 1-48 44-40 1-36 33-46 1-24 21-77 1-12 1330 1-00 0-00 The only certain way of determining the quantity of free potassa in any solid or liquid, is from the quantity of a dilute acid of known strength which it can saturate. The hydrate of potassa, or its ley, often contains a notable quantity of carbonate, the presence of which may be detected by lime water, and its amount be ascertained by the loss of weight which it suffers, when a weighed portion of the lev is poured into a weighed portion of dilute sulphuric acid poised in the scale of a balance. There are two other oxydes of potassium ; the suboxyde, which consists, according to Berzelius, of 90-74 of metal, and 9-26 oxygen ; and the hyperoxyde, an oranee-yellow substance, which gives oft' oxygen in the act of dissolving in water, and becomes potassa. It consists of 62 of metal, and 38 of oxygen. Carbonate of potassa is composed of 48 parts of base, and 22 of acid, according to most British authorities; or, in 100 parts, of 68-57 and 31-43; but according to Berzelius, of 68-09 and 31-91. Carbonate of potassa, as it exists associated with carbon in calcined tartar, passes very readily into the Bicarbonate^ on being moistened with water, and having a current of car- bonic acid gas passed through it. The absorption takes place so rapidly, that the mass becomes hot, and therefore ought to be surrounded with cold water. Tlie salt should then be dissolved in the smallest quantity of water at 120° Fahr., filtered and crvstAiIizGQ Pearl and Pot Ashes imported, in 1850, 184,043 cwts., in 1851, 199,911 cwts. POTASH, BICHROMATE OF. Mr. Charles Kober obtained in 1840 a patent for the use of bichromate of potash as a substitute for copperas, alum, and other mordant* for uniting the colouring ingredients in dyeing with the wool, in consequence of mutual affinity; the ordinary dyeing ingredients'beiug employed in conjunction with the bi- chromate ; he sometimes adds 2 lbs. of argol for 100 lbs. of wool. The chief use of the bichromate seems to be for brightening and fixing the common dyes and mordants. POTASH AND SODA, CAUSTIC. Mix a solution of 1 part of the dry carbonate salt with 1 part freshly prepared dry hydrate of lime, and allowing it to stand in a closed vessel for 24 hoiii-s at a temperature of 68» to 78«» Fahr., frequently shaking it The potash salt should be dissolved in 12 to 15, the soda salt in 7 to 15 parts of water; the carbonate of lime separates in a granulated state, and the clear caustic lye may be decanted. A weaker lye may be obtained from the residue by fresh treatment with water. POTASH, CHLORATE OF. Chlorate of potash may be economically made bj mixing 5^ atoms of quick lime with 1 of caustic potash, and passing a current of chlorine gas through the mixture, in a thin pasty state, with water at a boiling heat Under these conditions, chloride of calcium and chlorate of potash are produced, thus, by the use of lime, the enormous loss of potash, which in the ordinary process is converted into chloride, is avoided ; since, instead of producing 43 grs. for 100 grs. of potasli, 220 grs. may be obtained, Avhich approaches to the theoretical number 2G0. A fact which demonstrates in a remarkable manner how grAitly the chemical af- finity of chlorine for oxygen is increased by heat, is, that a mere trace of chlorate is produced when chlorine is passed into a mixture of lime and caustic potash at the ordi- nary temperature. Another point which results from these experiments is, the influence of the degree of concentration of the liquids. If, for instance, a solution of caustic potash, of 1 -040 spec gr. at 82°, and containing 34 grs. of potash in 1000 gre. of liquid, is mixed with 431 grs. of lime, or 6 equivs., only 131 grs. of chlorate are obtained. Another mixture, made with 1000 grs. of liquid containing 58-75 of potash and 6 equivs. of lime, gave 168 grs. of chlorate of potash. Lastly, by taking a solution of caustic potash of 11 10 sp. gr., and containing 102-33 of potash for 100 grs. of fluid, and adding to it 6 equivs. of caustic lime, heating the whole gradually to 122°, then passing a rapid current of chlorine to saturation (which raises the temperature to about 194°), filtering, evaporat- ing to dryness, redissolving in boiling water, and allowing the whole to cool, 220 gra. of pure chlorate of potash may be obtained. This process has been applied on a large •cale, and has perfectly succeeded. POTASH, PRL'SSIATE OF. See Prussian Blue. POTASSIUM (Eng. and Fr. ; Kalium, Germ.) is a metal deeply interesting, not only from its own marvellous properties, but from its having been the first link in the chain of discovery which conducted Sir H. Davy through many of the formerly mysterious and untrodden labyrinths of chemistry. The easiest and best mode of obtaining this elementary substance, is that contrived by Brunner, which I have often practised upon a considerable scale. Into the orifice of one of the iron bottles, as A,y/g. 889, in which mercury is imported, adapt, by screwing, a piece of gun-barrel lube, 9 inches long ; having brazed into its side, about 3 inches from its outer end, a similar piece of iron tube. Fill this retort two thirds with a mixture of 10 parts of cream of tartar, previously calcined in a covered crucible, and 1 of charcoal, both in powder ; and lay it horizontally in an air-furnace, so that while the screw orifice is at Uic inside waK, ihe extremity of the straight or nozzle tube may project a few inches beyond the brickwork, and the tube brazed into it at right angles may descend pretty close to the outside wall, so as to dip its lower end a quarter of an inch beneath the surface of some rectified naptha contained in a copper bottle surrounded by ice-cold water. By bringing tlie condenser-vessel so near the furnace, the tubes along which the potas- sium vapor requires to pass, run less risk of getting obstructed. The horizontal straight end of the nozzle tube should be shut by screwing a stopcock air-tight into it. Bjr opening the cock momentarily, and thrusting in a hot wire, this tube may be readily kept free, without permitting any considerable waste of potassium. The heat should be slowly applied at first, but eventually urged to whiteness, and continued as lone as potass jreted hydrogen continues to be disengaged. The retort, and the part of the nozzh; lube exposed to the fire, should be covered with a good refractory lute, as described under the article Phosphorus. The joints must be perfectly air-tight ; and the vessel freed from every trace of mercury, by ignition, before it is charged with the tartar-ash. . i l •.. Tartar skilfully treated in this way will afford 3 per cent, of potassium j and when it I ■1 ,M 460 POTASSIUM. it is observed to send forth green fumes, it has commenced the production of the m^y be enTployed ' ^^"^^^^^^^^^ ^^^^^ ^^^^^'^^^^ the following ?orm ofapplj^ A,>> 1146., represents the iron bottle, charged with the incinerated tartar- and r S'the"bot"ltanT?hrh t ^'^f 1 f^f' «'^'^^ '^'^^ *^^ placerbetwl'^tt bo^^^^^^ 01 tHe bottle and the back wall of the furnace, to keep the apparatus steadv during the operation Whenever the moisture is expelled, and the rJ^Trfai^tlv Sed thf tube should be screwed into the mouth of^the bottle, through a sS ifoTelit for H 1146 ^"^ ^^™« ^° apparently dry solid, of specific gravity 1-39. When this is exposed to the heat of 220« it fuses into a liquid nearly as thin as water; on cooling to 150° it takes the consistence of honey, and at 100° F^hr. L^^; f f f \''''\vr'l^- ^\ ""'* ^^ ^^^^ « considerable time at reii before it recovers Its pn tine state. When heated to 270° it boils briskly, gives off one-tenth of its weight liL Wll ^^'^^^.f tr^" '^^^*':^ ^°^^ * ^"e^^ y^"«^' brittle, but deliquescent mass, «a L 1 S ^"^-^/^ V w! P'-^^ ^^ concentrated to a much greater density than 1 34^ as to 1 -362 or if it be left faintly acidulous, in either case it lill not granulate, but wU IIT A ^/l t ''■l^^'^ ™3^^^' ^^ b^<^«"« » concrete mass, which may indeed be pul- verized, though It IS so deliquescent as to be unfit for the adulteratioi of raw sugar. r.lt ii,l •^'"''^ '" '"^ ^^' predicament, and is therefore, in my opinion, hardly Ime- ?pin.].Un^ "r '''^^' ^n"^' ^' '^ "^°^«* ^y «°y °^^«°s t« ^«rie'^^^^^ «^ copper praCtES iv!r.l "°^" T^P^y^^^^\of 100 parts of granular' Itarch sugar.^ Tlius, for Sif Zbftrurine " ^ "'' "^^""^'^ '''' ^^""^ "^ ^"^"^ ^^^ ^« ««timated to thj^«ll!,f Vx^''\ r^^i ^%"'^^ '"^ i^^ "^^''^ experiments, but it is not so good as the sulphate. The chloride of copper does not answer. Specific gravity is also an important criterion applied to sugar; that of the cane and beet root is 1-577, not l-eOfiS as given by Berzelius and other!; that of starch sugar in crystalline tufts, is 1-39, or perhaps 1-40, as it varies a little with its state of dryness. t.J.'^f P'T ^ ""^.^ • ^'^"^^^"s seventy per cent of sugar ; at the same density 2 9L0 /pT ^ '"^f ,^«°^^;«« seventy-five and a half per cent of concrete matter, drieH at 250 (Fahr.), and, therefore, freed from the ten per cent of water which it contains in the granular state. Thus another distinction is obtained between the two sugars in the relative densities of their solutions, at like saccharine contents per cent POTTERY, PORCELAIN. (Eng. and Fr. ; Steingut, Parzellan, Germ.) The French, who are fond of giving far-fetched names to the most ordinary thin?s, have dignified the art of pottery with the title of ceramique, from the Greek noun KepaL an earthen pot, compounded of two words which signify, in that lansjuape, burned clay. ' In relerence to chemical constitution, there are only two genera of baked stoneware The first consists of a fusible earthy mixture, along with an infusible, which when combined are susceptible of becoming semi-vitrified and translucent in the kiln. This constitutes porcelain or china-ware; which is either hard and genuine, or tender and spuriou«! according to the quality and quantity of the fusible ingredient. The second kind con! sists of an infusible mixture of earths, which is refractory in the kiln, and continues opaque. This is pottery, properly so called; but it comprehends several sub- species, which graduate into each other by imperceptible shades of difference. To ^?na &c earthenware, stoneware, flintware, fayence, delft ware, iron-stone The earliest attempts to make a compact stoneware, "with a painted glaze, seem to have originated with the Arabians in Spain, about the 9th century, and to have passed thence into Majorca, in which island they were carried on with no little success. In the 14th century, these articles, and the art of imitating them, were highly prized by the Italians, under the name of Majolica, and ;w)rcc/arw, from the Portuguese word for a cup. 1 he first fabric of stoneware possessed by them was erected at Fayenza, in the ecclesias- tical state, whence the French term faymce is derived. The body of the ware was usu- ally a red clay, and the glaze was opaque, being formed of the oxydes of lead and tin, along with potash and sand. Bernhard de Pallissy, about the middle of the 16th century, man- uiactured the first while /ayencc, at Saintes, in France; and not long afterwards tht Dutch produced a similar article, of substantial make, under the name of delftware, and delft /)orcc/«in, but destitute of those graceful forms and paintings for which the ware of layenza was distinguished. Common fayence may be, therefore, regarded as a strong, well-burned, but rather coarse-grained kind of stoneware. It was in the 17th century that a small work for making earthenware of a coarse description, coated with a common lead glaze, was formed at Burslem, in Staffordshire which may be considered as the germ of the vast potteries now established in that hThl; J °^\""f^<^^«ie was improved about the year 1690, by two Dutchmen, the thr!i K ^ ^'^V'l^'' introduced the mode of glazing ware by the vapor of salt, which they threw by handfuls at a certain period among the ignited goods in the kiln. But these were rude, unscientific, and desultory efforts. It is to the late Josiah Wedgewood, Esq. that this country and the world at large are mainly indebted for the ^eat modem advancement of the ceramic art. It was he who first erected magnificent factories, where every resource of mechanical and ch-mical science was made to co-operate with the arts of painting, sculpture, and statuar/, in perfecting this valuable department of the industry of nations. So sound were his principles, so judicious his plans of procedure. Zi ^rannnn''''^ r^ ^^^" prosecuted by his successors in Staffordshire, that a popula- tion of 60,000 operatives now derives a comfortable subsistence within a district formerly bleak and barren of 8 miles long by 6 broad, which contains 150 kilns, and is signifi- cantly called the Potteries. ' " o "" OF THE MATERIALS OF POTTERY OR PORCELAIN, AND THEIR PREPARATION. 1. CZay.— The best clay from which the Staffordshire ware is made, comes from Dorsetshire ; and a second quality from Devonshire ; but both are well adapted for working, being refractory in the fire, and becoming very white when burnt. The clay •s cleaned as much as possible by hand, and freed from loosely adhering stones at the pits where it is lug. In the factory mounted by Mr. Wedgewood, which may be re garded as a type )f excellence, the clay is cut to pieces, and then kneaded into a palp with water, by engines ; instead of being broken down with pickaxes, and worked wilk water by hand-paddles, in a square pit or water-tank, an old process, called bluu8:ing. The clay is now thrown into a cast-iron cylinder, 20 inches wide, and 4 feet high, or into a cone 2 feet wide at top, and 6 feet deep, in whose axis an upright shaft revolves, bearing knives as radii to the shaft. The knives are so arranged, that their flat sides lie in the plane of a spiral line ; so that by the revolution of the shaft, they not only cut through everything in their way, but constantly press the soft contents of the cylinder or cone obliquely downwards, on the principle of a screw. Another set of knives stands out motionless at right angles from the inner surface of the cylinder, and projects nearly to the central shaft, having their edges looking opposite to the line of motion of the revolving blades. Thus the two sets of slicing implements, the one active, and the other passive, operate like shears in cutting the clay into small pieces, while the active blades, by their spiral form, force the clay in its comminuted state out at an aperture at the bottom of the cylinder or cone, whence it is conveyed into a cylindrical vat, to be worked into a pap with water. This cylinder is tub-shaped, being about 4 limes wider than it is deep. A perpendicular shaft turns also in the axis of this vat, bearing cross spokes one below another, of which the vertical set on each side is connected by upright staves ffiving the moveable arms the appearance of two or four opposite square paddJe- boards' revolving with the shaft. This wooden framework, or large blunger, as it is called, turns round amidst the water and clay lumps, so as to beat them into a fine pap, from which the stony and coarse sandy particles separate, and subside to the bottom. When- ever the pap has acquired a cream-consistenced uniformity, it is run off through a series of wire, lawn, and silk sieves, of different degrees of fineness, which are kept in continual aeitation backwards and forward by a crank mechanism; and thus all the grosser parts are completely separated, and hindered from entering into the composition of the ware. This clay liquor is set aside in proper cisterns, and diluted with water to a standard density. . , ^ _ . 2. But clay alone cannot form a proper material for stoneware, on account of its great contractility by heat, and the consequent cracking and splitting in the kiln of the vessels made of it; for which reason, a silicious substance incapable of contraction must enter into the body of pottery. For this purpose, ground flints, called flint- powder by the potters, is universally preferred. The nodules of flint extracted from the chalk formation are washed, heated redhot in a kiln, like that for burning lime, and thrown in this state into water, by which treatment they lose their translucency, and become exceeding brittle. They are then reduced to a coarse powder in a stamping- mill, similar to that for stamping ores; see Metallurgy. The pieces of flint are laid on a strong grating, and pass through its meshes whenever they are reduced by the stamps to ascertain state of comminution. This granular matter is now transferred to the proper flint-mill, which consists of a strong cylindrical wooden tub, bottomed with flat pieces of massive chertf or hornstone, over which are laid large flat blocks of similar chert, that are moved round over the others by strong iron or wooden arms projecting from an upright shaft made to revolve in the axis of the mill-tub. Sometimes the active blocks are fixed to these cross arms, and thus carried round over the passive blocks at the bot- tom. See infrhf under Porcelain, figures of the flint and feldspar mill. Into this cyl- indrical vessel a small stream of water constantly trickles, which facilitates the grinding motion and action of the stones, and works the flint powder and water into a species of pap. Near the surface of the water there is a plug-hole in the side of the tub, by which the creamy-looking flint liquor is run off from time to time, to be passed through lawn or silk sieves, similar to tn:?e used for the clay liquor; while the particles that remain oa the sieves are returned into the mill. This pap is also reduced to a standard density by dilution with water ; whence the weight of dry silicious earth present, may be deduced from the measure of the liquor. The standard clay and flint liquors are now mixed together, m such proportion by measure, that the flint powder may bear to the dry clay the ratio of one to five, or occa- sionally one to six, according to the richness or plasticity of the clay ; and the liquors are intimately incorporated in a revolving churn, similar to that employed for making the clay- pap. This mixture is next freed from its excess of water, by evaporation in oblong stone troughs, called slip-kilns^ bottomed with fire-tiles, under which a furnace flue runs. The breadth of this evaporating trough varies from 2 to 6 feet ; its length from 20 to 50 ; and its depth from 8 to 12 inches, or more. By the dissipation of the water, and careful agitation of the pap, a uniform doughy mass is obtained; which, being taken out of the trough, is cut into cubical lumps. These are piled in heaps, and left in a damp cellar for a considerable time ; that is, several months, in large manufactories. Here the dough suffers disintegration, pronoted by a kind of fermentative action, due probably to some vegetable matter in the vratei Vol. II 8 466 POTTERY. Hi i- y m m M :, f and the clay ; for it becomes black, and exhales a fetid n/?nr tk mi 3 ^. cious particles get disintegrated also by the action of the wnt.r^ argillaceous and siU. ware made with old paste is found to be more homo^eouT £ "" '"'^* ^^^ '^'^' ^^^ to crack or to get disfigured in the bakinra" the ware S^hh^'"'^ ^""^ ""' '^ ^^^ But this chemical comminution must be aided bTmp^^.- ''^'^''' P^'^^' which is called the potter^s ,/o;,4TlS^; It^on.is^Tn "•''^'•^^^""^ ' the first of the hands, and, with a twist of both atCce tearin^it "nS two '"''"= ^ "'^''•"^ ""^^^ ^" a wire. These are again slapped to-ethe. with fnr.'« V /^ two pieces, or cuttmg it with ia Which they adhered beffe S thfn dasirefd^Tin a Wd'^^^^^^^^ ts^'" '^°"^ ^^«' torn or cut asunder at Hcrht jmcri^o • 1 , " ." woara. ihe mass is once more fixed ones) are minced to ^allmo^^^^^^^ reaction of pressure into an^S" of tTeboXr^^ ^°'''^ ^'l^"^^^^ ^^ '^^ screw-like pipe about 6 inches square proceed TLdnulht'' ''iT"'- ^'""^ ^'^^^'^ ^ ^^«"^«»tal and is then cut into lengths of about* 12 inoh. ^Vk ""^"^.^ ^^ '''"^ *^^'"^"?^ ^^^^ «»tlet, back into the cyIindL,'and subSei to th/;. ^''' '^'^ ^'^^'''' ^' ^"^"^^ ^--^ thrown luinps have their%articies perfec ]> btnde^^^^^ "^^^^" «"^ ^-^"' ^^^ ^he precede their being set aside to ripln L a lamp cd lar In FrZll\r\^^'"''''''r^l IS not worked in such a machine; but aftefbdn' beat with Z. f ^t;;"^^^^^ dough common also in England, it is laid down on a clel„ floor and Iw t °'^"-''' ^ P'"^''^'^^ upon it with naked feet for a considerable time w^lS • ^ '"^^^'^ '« set to tread centre to the circumference and f^om d! .u ' ? " '" * ^^''^^ direction from the and also in China (to jud'eVrom Hp rv ^"^""?^^r^"ce to the centre. In Sweden, ofmakingporSnMheday^sTroSLnt^^^^^^ ^r^'"*'"=' \^^'^ ^^P^^^^"' t^^"" "^^nner' all cases,\neaded like bakers douoh bv foldin " Wt T' 1 ^ "^^"- ^^ ^^ ^^erwards, in it out, aUernatelv. " ' ^ ^''^'^'''^ ^^''^ ^^'^ ^^'^ "!>«» itself, and kneadLg eitre'VXn'b^Lt^ra'n'dtlu^^^^^ ^ l^^^^^- -^'^ ^ -e, lifting up violent treatment of^ laris repea^dS^^^^^^^^^^ ^''"^'"'r' "" ^^^ ^^^^^' ^"^^^^^^^ for the smallest remaining vesicle exnandklTnLL-^^^^ air-bubbles is removed, warts upon the ware expanding in the kiln, would be apt to cause blisters oi ^t^^^:t^tJ^:IZ^^ P--^ - have next to describe con^stroTl^up^trrlTara This " is fixed, by its cent're, a hori^onJardisc or ckf llr nLcn^wniS^^'^ "" '^' ''^ ^^^^^^^^ great for the largest stoneware vessel to sLnduX The o?^^^^^^ ed,and runs in a conical step, and its collar a little hplnJ^Lt u ?^^^. '' P**'"^- turned, is embraced in a socket attached to the wooden f.^r^^^^ r .if ^'^^'i, ^^ing truly a pulley fixed upon it, with grooves for 3 soeedso^^^^^^ ^ ^^'J^'^'u ^^" ^^«^^ ^^ a fly-wheel, by whose^evolut oHny deLedranidi^vof rn .^ '"^^u' ''•^"^ P^^sesfrom and its top-board. This wheeT when sriall Zlfll f /^'^i'^l^ "^^^ ^^^ gi^en to the shaft lathe, and then it is driven by a tTeadle and'o^nl i '1? '^"?'^^'' *^^ '"^ '^^ '^'^^^^ turned by the arms of aUorer ^nlr ^ I "7 Y^^" ""^ ^^"S^"* dimensions, it is* a large thick c^scT Par fp^^^^^^^^^ whTch rw^'tf ' '^"7?"^"'^ plate is replaced by without the interventln of'atu^Iey and fly w^^^^^^^ TnTlff^''' hand of the potter^ power for fashioning small ve^^sels The mlT^^^^^ centrifugal or gauged by an experienced hand The ^0^^? 1° »>« ^^rown, is weighed out centre of the revolving boardTanddiLnc^hrshanrr ""'^ff ^^""^ ^^' ^"°^P «" the water, he works up the clay into a ^Sl Lf^^^^^^ »"*, of alternately, till he has secured the finii /?• , *^>^';^e^ ^nd then down into a cake. proper for'i to the veUTunder a^t spe roTrltn'^'-^^^^^ ^^^^ ^^^ ^^« wooden pegs and gauges. He now cm! Jr^off f .v, u ^'''"' regulating its dimensions by fastened\o\ handle at either end The vesllthtt ^'? w t""''''' ?^«"« brass wire, tuation where it may dry -raduali; to a nif • ! ""^^^^ fashioned is placed in a si- called the green state, iPpLssesses a^l?;^^;' P^!"';^ ^' * ^^''^^^ «»«?« of the dning. It is then tfken to anotheMSe?calfed the turnin//?r ^V'"^.'^^"' ^"* ^* ^^ »>^ked: moisture to the vertical face of kwoodei chuck an'^' ^ '^ '^ ' ^"^'^'"^ ^^ ^ "'"^ with a very sharp tool, which alL s^o"hs^r\fteVth^^^^ '""'"rlTV'' ^^Pf '^''^ ' oth steel surface. ^"^^ ^^^^ *' ? ^^'S^tly burnished with 11 POTTERY. 467 DESCKIPTION OF THE P0TTEB*S LATHE. A, /g. 1148, is the profile of the English potter's lathe, for blocking oot round ware ; c is the table or tray ; a is the head of the lathe, with its horizontal disc ; a, 6, is the upright shaft of the head; d, pulleys with several grooves of dill'erent diameters, fixed upon the shaft, for receiving the driving-cord or band ; fe is a bench upon which the workman sits astride ; «, the treadle fool-board ; Ms a ledge-board, for catching the shavings of clay which fly off from the lathe ; A is an instrument, with a slide-nut i, for measuring the objects in the blocking out; c is the fly-wheel with its winch-handle r, turned by an assistant ; the sole-frame is secured in its place by the heavy stone p ; /is the oblong guide-pulley, having also several grooves for con- verting the vertical movement of the fly-wheel into the horizontal movement of the head of the lathe. D is one of the intermediate forms given by the potter to the ball of clay, as it revolves upon the head of the lathe. In large potteries, the whole of the lathes, both for throwing and turning, are put ia motion by a steam-engine. The vertical spindle of the lathe has a bevel wheel on it, which works in another bevel toothed wheel fixed to a horizontal shaft. This shaft is provided with a long conical wooden drum, from which a strap ascends to a similar co- nical drum on the main lying shaft. The apex of the one cone corresponds to the base of the other, which allows the strap to retain the same degree of tension (see the conical drum apparatus of the Stearinc-press), while it is made to traverse horizontally, in order to vary the speed of the lathe at pleasure. When the belt is at the base of the driving- cone, it works near the vertex of the driven one, so as to give a maximum velocity to the lathe, and vice versa. During the throwing of any article, a separate mechanism is conducted by a boy, which makes the strap move parallel to itself along these conical drums, and nicely re- gulates the speed of the lathe. When the strap runs at the middle of the cones, the velocity of each shaft is equal. By this elegant contrivance of parallel cones revei-se^ the velocity rises gradually to its maximum, and returns to its minimum or slower motion when the workman is about finishing the article thrown. The strap is then transferred to a pair of loose pulleys, and the lathe stops. The vessel is now cut off at the base with small wire ; is dried, turned on a power lathe, and polished as above described. The same degree of dryness which admits of the clay being turned on the laihe, also suits for fixing on the handles and other appendages to the vessels. The parts to be attached, being previously prepared, are joined to the circular work by means of a thin paste which the workmen call slip, and the seams are then smoothed off with a wet sponge. They are now taken to a stove-room heated to 80** or 90** F., and fitted up with a great many shelves. When they are fully dried, they are smoothed over with a small bundle cf hemp, if the articles be fine, and are then ready for the kiln, which is to convert the tender clay into the hard biscuit. A great variety of pottery wares, however, cannot be fashioned on the lathe, as they are not of a circular form. These are made by two different methods, the one called press-work, and the other casting. The press-work is done in moulds made of Paris plaster, the one half of the pattern being formed in the one side of the mould, and the other half in the other side : these moulding-pieces fit accurately together. All vessels of an oval form, and such as have flat sides, are made in this way. Handles of tea- pots, and fluted solid rods of various shapes, are formed by pressure also ; viz., by squeezing the dough contained in a pump-barrel through diflferent shaped orifices at its hot- torn, by working a screw applied to the piston-rod. The worm-shaped dough, as it issues, is cut to proper lengths, and bent into the desired form. Tubes may be also made on the same pressure principle, only a tubular opening must be provided in the bottom plate of the clay-forcing pump. I i I •;i!i 468 FOTTERY. The other method of fashioning earthenware articles is caUed casting, and is, perhaps, the most elegant for such as have an irregular shape. This operation consists in pour, ing the clay, in the state of pap or slip, into plaster moulds, which are kept in Ji desiccated state. These moulds, as well as the pressure ones, are made in halves which nicely correspond together. The slip is poured in till the cavity is quite full, and is left m the mould for a certain time, more or less, according to the intended thickness of the vessel. The absorbent power of the plaster soon abstracts the water, and makes the coat of clay m contact with it quite doughy and stiff; so that the part still liquid being poured out, a hollow shape remains, which when removed from the mould constitutes the half of the vessel, bearing externally the exact impress of the mould. The thickness of the clay varies with the time that the paste has stood upon the plaster. These cast articles are dried to the green slate, like the preceding, and then joined accurately with slip. Imitations of flowers and foliage are elegantly executed in this way. This operation, which is called furnishing, requires very delicate and dexterous manipu- lation. *^ The saggers for the unglazed colored stoneware should be covered inside with a glaze composed of 12 parts of common salt and 30 of potash, or 6 parts of potash and 14 of salt ; which may be mixed with a little of the common enamel for the glazed pottery saggers. The bottom of each sagger has some bits of flints sprinkled upon it, which become so adherent after the first firing as to form a multitude of little promi- nences for setting the ware upon, when this does not consist of plates. It is the dutv of the workmen belonging to the glaze kiln to make the saggers during the intervals of their work j or, if there be a relay of hands, the man who is not firing makes the saggei-s. . The English kilns difler from those of France and Germany, in their construction, in the nature of their fuel, and in the high temperature required to produce a surface suflUciently hard for a perfectly fine glaze. When the ware is sufliciently dry, and in sufllicient quantity to fill a kiln, the next process is placing the various articles in the baked fire-clay vessels, which may be either of a cylindrical or oval shape ; called gazettes, Fr. ; kapseln. Germ. These are from 6 to 8 inches deep, and from 12 to 18 inches in diameter. When packed full of the dry ware, they are piled over each other in the kiln. The bottom of the upper sagger forms the lid of its fellow below ; and the junction of the two is luted with a ring of soft clay applied between them. These dishes protect the ware froin being suddenly and unequally heated, and from being soiled by the smoke and vapors of the fuel. Each pile of saggers is called a bung. POTTERY KILX OF STAFFORDSHIRE, Figs. 1149, 60, 61, 62, 63., represent the kiln for baking the biscuit, and also forrmi- ning the glaze, in the English pottenes. 1160 1161 ■J Uti ii POTTERY. 469 1152 a, «, figs. 1149, 1160.1161. are the furnaces which heat the kiln ; of which h, in^g 1U9 are the upper mouths, and 6' the lower ; the former being closed more or less by the flre-tile z, shown in ^g. 1153. - ,. . x ^^Ko /is one fireplace ; for the manner of distributing the fuel in it, see fig. 115d. It V Hzs 1149 and 1153 are the horizontal and vertical flues and chimneys for con- duSing the'flame and smoke. / is the laboratory, or body of the kiln ; leaving its^oor k sloping sliffhtly downwards from the centre to the circumference, x, V* « ^he slit of the horizontal register, leading to the chimney flue y of the furnace, being the first regu lator; x, «, is the vertical register conduit, leading to the furnace or mouth /, be ng he second regulator; v is the register slit above the furnace and its vertical flue leading into the b^y of the kiln ; v\ c, slit for regulating flue at the shoulder of the kUn ; t ^ an arch which supports the walls of the kUn, when the furnace is ^^^^^H^^^'^ ^"l are small flues in the vault s of the laboratory. h,fig. 1160,is the central flue, called ian«/s./.teries, because it is smooth enough ; but is immediately transported to the place where it is to be dipped in the glaze or enamel tub. A child makes the pieces ring, by striking with the handle of the brush, as he dusts them, and then immerses them into the glaze cream ; from which tub thev are taken out by the enamellcr, and shaken in the air. The tub usually contains no' more than 4 or 5 inches depth of the glaze, to enable the workman to pick out the articles more readily, and to lay them upon a board, whence they are taken by a child to the glaze kiln. Glazing. — A good enamel is an essential element of fine stoneware ; it should experi- ence the same dilatation and contraction by heat and cold as the biscuit which it covers. The English enamels contain nothing prejudicial to health, as many of the foreign glazes do ; no more lead being added to the former than is absolutely necessary to convert the sili'cious and aluminous matters with which it is mixed into a perfectly neutral class. Three kinds of glazes are used in Staflordshire ; one for the common pipe-clay or cream-colored ware; another for the finer pipe-clay ware to receive impressions, called printing body ; a third for the ware which is to be ornamented by painting with the The glaze of the first or common ware is composed of .53 parts of white lead, 16 of Cornish stone, 36 of ground flints, and 4 of flint glass; or of 40 of white lead, 36 of Cor- nish stone, 12 of flints, and 4 of flint or crystal glass. These compositions are not fritted ; but are employed alter being simply triturated with water into a thin paste. The following is the composition of the glaze intended to cover all kinds of figures primed in metallic colors ; 26 parts of white feldspar are fritted with 6 parts of soda, 2 of nitre, and 1 of borax ; to 20 pounds of this frit, 26 parts of feldspar, 20 of white lead, 6 of ground flints, 4 of chalk, 1 of oxyde of tin, and a small quantity of oxyde of cobalt, to take off the brown cast, and give a faint azure tint, are added. The following recipe may also be used. Frit together 20 parts of flint glass, 6 of flints, 2 of nitre, and 1 of br.rax; add to 12 parts of that frit, 40 parts of white lead, 36 of feld spar, 8 of flints, and 6 of flint glass ; then grind the whole together into a uniform cream- consistenced paste. ... j r io As to the stoneware which is to be painted, it is covered with a glaze composed ol 13 parts of the printing-color frit, to which are added 50 parts of red lead, 40 of white lead, and 12 of flint ; the whole having been ground together. The above compositions produce a very hard glaze, which cannot be scratched by the knife, is not acted upon by vegetable acids, and does no injury to potable or edible arti- cles kept in the vessels covered with it. It preserves for an indefinite time the glassy lustre, and is not subject to crack and exfoliate, like most of the Continental stoneware made from common pipe-clay. In order that the saggers in which the articles are baked, after receiving the glaze, may not absorb some of the vitrifying matter, they are themselves coated, as above mentioned, with a glaze composed of 13 parts of common salt, and 30 parts of potash, simply dissolved in water, and brushed over them. Glaze kiln.— This is usually smaller than the biscuit kiln, and contains no more than 40 or 45 bungs or columns, each composed of 16 or 17 saggers. Those of the first bung rest upon round tiles, and are well luted together with a finely ground fire-clay of only moderate cohesion ; those of the second bung are supported by an additional tile. Th€ lower sa^^^ers contain the cream-colored articles, in which the glaze is softer than that which covers the blue printed ware ; this being always placed in the intervals between the furnaces, and in the uppermost saggers of the columns. The bottom of the kiln, where the glazed ware is not baked, is occupied by printed biscuit ware. Pyrometric balls of red clay, coated with a very fusible I'^^d enamel, are employed m. the English potteries to ascertain the temperature of the ^/^^^/^l"^- ^^his enameUs 80 tiM, «nd the clav upon which it is spread is so fine-grained and compact, that even wnen exnosed for th el SoursTo the briskest flame, it does not lose its lustre The color of ^uIZTv «lnne chanee«; wherebv the workman is enabled to udge of the degree of heal •tVn ^he ki?n At f&Uhe b^^^ have a pale red appearance ; but they become browner w!h the inc ease of thf temperature. The balls, when of a slightly dark-red color, indi- Tate the de^Tof^^^^^^^ 1^-d glaze of pipe-clay ware; but if they become dark brown the glaze will be much too hard, being that suited for trmstane ware ; lastl} , when ?he7acqufre an almost black hue, they show a degree of heat suited to the formation of * t^S"^^^ himself at each round with a stock of these ball watckes, reserved from the preceding baking, to serve as objects of comparison; and he never slackens the S- till he has obtained the same depth of shade, or even somewhat more; for t mavCremark^, that the more rounds a glaze kiln has made, the browner tne balk may be remariveu, enamel-ware sooner than an old one ; Z\Z':itleM^n^^^^^^^ The watch-balls of these first rounds Save geTerah not so deep a color as if they were tried m a furnace three or fou^ nTonthf old After this period, cracks begin to appear m the furnaces ; th. horizontal Zes 'ot parttau/ obstructed, 'the joinings of the brickwork become loose; m conse- ."" nV wWh here is a loss of heat and waste of fuel ; the baking of the glaze takes STon'er ime aVd he p^rometrL balls assume a different shade from what they had on a longer time, anu I i watches are of no comparable use after twofnonth^ '"The baking of enamel is commenced at a low temperature, and the heat irnrreWly increased; when it reaches the melting point of the glaze, it must be Ltefed'by :ufhraddmr k fueH afte?which the kiln is allowed from 5 to 6 hours to ^^liump. -The naintin-s and the printed figures applied to the glaze of stone- Muffles.— lhe pamun^t, ^^^^ ^^^ porcelain are baked m muffles of a peculiar form. Fig. 1154. is a lateral elevation of one of these muffles ; yjg.1155 is a front view. The same letters denote the same parts in the two figures. a is the furnace ; 6, the oblong muffle, made of fire-clay, surmounted with a dome pierced with three apertures k, k, k, for the escape of the vaporous matters of the col- ors and volatile oils with which they are ground up ; c is the chimney ; d, d, feed- holes, by which the fuel is introduced ; «, the fire-grate ; /, the ash-pit; channels arc u, . ^ , ^ , .^ . - ■ ,^ ■ left in the bottom of the furnace to facih- tate the passage c^- the flame ^-eath th^ mur^^^^^^^^^^^ thS mt^o^lStX^^^^^^^^ eommunication across the fumace^m^^ ^^ ^,^ ,^.^^ ,, is passing withm ; k, k, are the ^.^^^'^^^J"^^ . f ^^^ chimney to modify its draught, flame; ^ i^ ^n opening ^^X)ped out m the front o^^^^^ placed in the muffle The articles which Y^J^-'^^Zv^lsx^vm^^^ ^^^t. The muffle without saggers, upon tripods, or «^97^^f ^^^/X""^^^^ ^ound its edges. The fuel being charged, its mouth »^<^^«^^d w^^^h a fir^tile well M ^ is then kindled in the f^^^'V^^^^K^; f^^^^ out.tples, and for examining the interior of in which a small openmg is left for .t^^^i^^^^^^^^^o a stron- iron wire, show the progress Xe the muffle on an sides and thence rises «p the cl,^^^^^^^^^ also' to aid in fluxing the cobalt. ■ I . lit I '11 i; m 472 POTTERY. The following are the processes tvsually practised in Staffordshire for printing nndef the glaze. The cobalt, or whatever color is employed, should be ground upon a porphyry slab, with a varnish prepared as follows: — A pint of linseed oil is to be boiled to the consist- ence of thick honey, along with 4 ounces of rosin, half a pound of tar, and half a pint of oil of amber. This is very tenacious, and can be used only when liquefied by heat ; which the printer effects by spreading it upon a hot cast-iron plate. The printing plates are made of copper, engraved with pretty deep lines in the common way. The printer, with a leather muUer, spreads upon the engraved plate, previously heated, his color, mixed up with the above oil varnish, and removes what is superfluous with a pallet knife ; then cleans the plate with a dossil filled with bran, tapping and wiping as if he were removing dust from it. This operation being finished, he takes the paper intended to receive the impression, soaks it with soap-water, and lays it moist upon the copper-plate. The soap makes the paper part more readily from the copper, and the thick ink part more readily from the biscuit. The copper-plate is now passed through the engraver's cylinder press, the proof leaf is lifted off and handed to the women, who cut it into detached pieces, which they apply to the surface of the biscuit. The paper best fitted for this purpose is maJe entirely of linen rags ; it is very thin, of a yellow color, and unsized, like tissue blotting-paper. The stoneware biscuit never receives any preparation before being imprinted, the oil of the color being of such a nature as to fix the figures firmly. The printed paper is pressed and rubbed on with a roll of flannel, about an inch and a half in diameter, and 12 or 15 inches Ions, bound round with twine, like a roll of tobacco. This is used as a burnisher, one end of it being rested against the shoulder, and the other end being rubbed upon the paper ; by which means it transfers all the engraved traces to the biscuit. The piece of biscuit is laid aside for a little, in order that the color may take fast hold ; it is then plunged into water, and the paper is washed away with a sponge. When the paper is detached, the piece of ware is dipped into a caustic alkaline ley to saponify the oil, after which it is immersed in the glaze liquor, with which the printed figures readily adhere. This process, which is easy to execute, and very economical, is much preferable to the old plan of passing the biscuit into the muffle after it had been printed, for the purpose of fixing and volatilizing the oils. When the paper impression is applied to pieces of porcelain, they are heated before, being dipped in the water, be- cause, being already semi-vilnfied, the paper sticks more closely to them than to the bis- cuit, and can be removed only by a hard brush. The impression above the glaze is done by quite a different process, which dispense? with the use of the press. A quantity of fine clean glue is melted and poured hot upon a large flat dish, so as to form a layer about a quarter of an inch thick, and of the consist- ence of jelly. When cold it is divided into cakes of the size of the copper-plates it is in- tended to cover. The operative (a woman) rubs the engraved copper-plate gently over with linseed oil boiled thick, immediately after which she applies the cake of glue, which she presses down with a silk dossil filled with bran. The cake licks up all the oil out of the engraved lines ; it is then cautiously lifted off, and transferred to the surface of the glazed ware which it is intended to print. The glue cake being removed, the enamel surface must be rubbed with a little cotton, whereby the metallic colors are attached only on the lines charged with oil : the piece is then heated under the muffle. The same cake of glue may serve for several impressions. Ornaments and co/ormg.— Common stoneware is colored by means of two kinds of apparatus ; the one called the blowing-pot, the other the worming-pot. The ornaments made in relief in France, are made hollow (intaglio) in England, by means of a mould engraved in relief, which is passed over the article. The impression which it produces is filled with a thick clay paste, which the workman throws on with the blowing-pot. This is a vessel like a tea-pot, having a spout, but it is hermetically sealed at top with a clay plug, after being filled with the pasty liquor. The workman, by blowing in at the spout, causes the liquor to fly out through a quill pipe which goes down through the clay plug into the liquor. The jet is made to play upon the piece while it is being turn- ed upon the lathe ; so that the hollows previously made in it by the mould or stamp are filled with a paste of a color different from that of the body. When the piece has acquired sufficient firmness to bear working, the excess of the paste is removed by an instrument called a tournasiny till the ornamental figure produced by the stamp be laid bare; in which case merely the color appears at the bottom of the impression. By passing in this manner several layers of clay liquor of different colors over each other with the Mowing-pot, net-work, aud decorations of dinereut colors and shades, are very rapiuiy produced. The seri)entine or snake pots, established on the same principle, are made of tin plate In three compartments, each containing a different color. These open at the top cf POTTERY. 473 the vessel in a common orifice, terminated by small quill tubes ^l^^Hfi^e l^d are ^i^t the three colors flow out at once in the same proportion at the one orifice and are lei •all upon the piece while it is being slowly turned upon ^^e lathe ;whereb> c^unousser pent-like ornaments may be readily obtained The clay liquor o^gl^; /^^ Ide wU^ u'?h the stoneware paste. The blues succeed best when the ornaments are made witn ''^iSrf:rf«^^^^^^^ -talUc mstre being applied only to ^:^r «Lz:^!^ iL^:^o^d^of a^;::J^^r^^ ''The'"w;r and platina lustres are usually laid upon a ^ ^^ rcol^red '4orn7' T^ and copper, en account of their transparency succeed only "P?" ^/^^r. .^^^^^^ '••The Stn"ZunXtre is almost always applied lo a paste body made on purpose .nrc:a!:d':Uh 1 a^v^described lead glaze This paste is brown and co„.s^s of 4 nnru nf rlav 4 narts of fliuts, an equal quantity of kaolin (china cla>), ana o pans oi fe£ar To make^b^^^^^ in relief upon a body of white paste, a liquor ,s mixed uf riUhilpa'CwhS ought to weigh 26 ounces per pint, in order to unite weU with ^^^£i;^^^ir ::^:^^^- '^r^ -d then .^^ --^^^^^ fine gold in 288 gfains of an aqua regia, composed of 1 ounce ^^^'bi? and then poTr of muriatic acid; add to that solution 4| gr^^^^^, f §^^»%^'"' ^^^\V^^.,^„^^^^ some of that compound solution into 20 S''^^"'^. ^^ »'^1^'^°\^[ ^"^i*,^"' of oil of turpentine. The balsam of sulphur is P^^P-'-^ed by heating a I^'^* ^n^^^^f^^^^ and 2 ounces of flowers of sulphur, stirring them continually till the J" f ^[^ ^^-["^^^^^ boil • it is then cooled, by setting the vessel in cold water ; after which it »7^»'^'^«^^^*^{;f^^> ^nd 'stfafned through line'n. The above ingredients, after being ^^^^^^^^^^^^ \\l f lowed to settle for a few minutes ; then the remainder of the solution ol gom is lo oc po" ed in and the wioTe is to be 'trituiated till the mass has assumed such a consistence [hat the i;estle will stand upright in it; l^^^^y' ^?^^'^f,°^"^!,t.?reL read, to^rpplie^ grains of oil of turpentine, which being ground m, ^^f ?f^i"/H.". ^ave Lt a su^^^^^^^^ If the lustre is too light or pale, more gold must be added, and if it have not a sumcieni ly viclet or purple tint, more tin must be used. „„i;c>,pH ^terl another ^ Platina lustrl-Or this there are two kinds ; one ^^^'^f^^^^^^fj^^ 111^1° ina lighter and of a silver-white hue. To give stoneware the steel c^orwUii^latia^ this metal must be dissolved in an aqua regia ^J^^P^^^^^^ ^ Parts of muriat c ac^^^ 1 part of nitric. The solution being cooled, and poured »^/° /^^^f ^^J^f'!. ^^^^^^ added to it, drop by drop, with continual stirring with a ?^«VfiuVr J If the platina posed of equal parts of tar and sulphur boiled m l^«f f/^!,^"J,f,^^f/f '^ we^ it must solution be too strone, more spirit of tar must be added to it; but /^^^^u fhe ' miZ?e be concentrated by boiling, Thus being brought to the PX^vm lif the asp^t may be spread over the piece, which being put into the muffle, will take the aspect ""^Th^^oxvde of Dlatina by means of which the silver lustre is given to stoneware, is pre- Theox>deo platina, D) mea s saturation the metal in an aqua regia ST, isVaced upon a sand-bath, and the platina solution l^^-^J P^hf to be washed will fall down in the form of the well-known yellow Precuntate, which is to be washea with cold water till it is perfectly edulcorated, then dried, and put up for use This metallic lustre is applied very smoothly by means of a flat camel's hair brush. It Sc kiln, but they get their proper appearance by being rubbed with cotton. Platina and sold lustre ; by other recipes. ■ r ^a ^r o Txf>rt« nf Pa I/u./re.-Dissolve 1 ounce of platinum in ^^^J J^«.f.^V,<^;,"/f. ,1^:,^^^^^^ muriatic acid and 1 part of nitric acid, with heat upon a sand-bath, till the liquid is reduced Totwo thirds of its v'olume ; let it cool ; ^-^^^ ij\« ;;„\7jrrm^^^^^^^ drop bv drop, with constant atirring, some distilled tar, nnt 1 such a mixture is p as will dve k good result in a trial upon the ware m the kiln. If the l«^trej,yoo in tense, more ta? must be added ; if it be too weak, the mixture must be concentrated by '"tij .X-LTs-solve four shillings' worth of gold in aqua regia with a gentle heaU Vol. IL ^ ^ I n I 1 i '414 POTTERY. POTTERY. 475 I II To the solutior., when cool, add 2 grains of grain tin, which will immediately dissolve. Prepare a mixture of half an ounce of balsam of sulphur with a little essence of turpen- tine, beating them together till they assume the appearance of milk. Pour this mixture into the solution of gold and tin, drop by drop, with continual stirring ; and place the whole in a warm situation for some time. ]t is absolutely necessary to apply this lustre only u )on an enamel or glaze which haa already passed through the fire, otherwise the sulphur yould tarnish the composition. These lustres are applied with most advantage upon chocolate and other dark grounds. Much skill is required in their firing, and a perfect acquaintance with the quality of the glaze on which they are applied. jin iron lustre is obtained by dissolving a bit of steel or iron in muriatic acid, mixing this solution with the spirit of tar, and applyino: it to the surface of the ware. jlventurine glaze. — Mix a certain quantity of silver leaf with the above-described soft glare, grind the mixture alontr with some honey and boiling wat r, till the metal assume the appearance of fine particles of sand. The claze, being natu- liiy of a yellowish hue, gives a t^oMen tint to the small fragments of silver disseminated thiough it. Molybdena may al>o be applied to produce the aventurine aspect. The granite-like gfld lustre is produced by throwing lisfhtly with a brush a few drops of oil of turpentine upon the goods already covered wiih the preparation for gold lustre. These cause it to separate and appear in particles resembling the surface of granite. When marblina: is to be 2:iven to stoneware, the lustres of gold, platir \, and iron are used at once, which blending in the fusion, form veins like those of marble. Pottery aiii slonewtre of the Wedgcivood color. — This is a kind of semi- vitrified ware, called dry bodies, which is not susceptible of receiving a superficial glaze. This pottery is composed in two ways : the first is with barytic earths, which act as fluxes upon the clays, and f )rm enamels : thus the Wediiewoo 1 j-isper ware is made. The white vitrifying pastes, fit for receivinor all sorts of metallic colors, are composed of 47 parts of sulphate of barytes, 15 of feldspar, 26 of Devonshire clay, 6 of sub^hate of lime, 15 of flints, and 10 of sulphate of stronliles. This composition is capable of receiving the tints of the metallic oxydes and of the ochrous metallic earths. Manganese produces the dark purple color; gold precipitated by tin, a rose color ; antimony, orancre; cobalt, diflTcrent shades of blue ; copi)er is employed for the browns and the dead-leaf greens ; nickel ffiv-^es, with potash, ereenish colors. » One p^r cent, of oxyde of cobalt is added ; but one half, or even one quarter, of a per cent, would be sufficient to produce the fine Wedsrewood blue, when the nickel and man- ganese constitute 3 per cent., as well as the carbonate of iron. For the blacks of this kind, some English manufacturers mix black oxyde of manganese with the black oxyde of iron, or with ochre. Nickel and umber allord a fine brown. Carbonate of iron, mix- ed with bole or terra di Sienna, gives a beautiful tint to the paste; as also manganese with cobalt, or cobalt with nickel. Antimony produces a very fine color when combined with the carbonate of iron in the proportion of 2 per cent., along with the ingredients necessary to fjrm the above-described vitrifying paste. The following is another vitrifying paste, of a nmch softer nature than the preceding. Feldspar, 30 parts; sulphate of lime, 23; silex, 17; potter's clay, 15; kaolin of Corn- wall (china clay), 15; sulphate of baryta, 10. • These vitrifying pastes are very plastic, and may be worked with as much facility as English pipe-clay. The round ware is usually turned upon the lathe. It may, however, be moulded, as the oval pieces always are. The more delicate ornaments are cast in hollow moulds of baked clay, by women and children, and applied with remark- able dexterity upon the turned and moulded articles. The colored pastes have such an affinity for each other, that the detached ornaments may be applied not only with a little gum water upon the convex and concave forms, but they may be made to adhere without experiencins: the least cracking or cliinks. The colored pastes receive only one fire, unless the inner surface is to be glazed ; but a gloss is given to the outer sur- face. The enamel for the interior of the black '^'^^direwood ware is composed of 6 parts of red leal, 1 of sijjex, and 2 ounces of manganese, when the mixture is made in pounds* -*"ei?ht. The operation called smearing, consists in giving an external lustre to the un^lazed s,emi-viinf.ed ware. The articles do not in this way receive any immersion, nor even the aid of the brush or pencil of the artist ; but they require a second fire. The saggers are coated with the salt glaze already described. These cases, or saggers, communicate by reverberation the lustre so remarkable on the surface of the English stoneware ; which one misht suppose to be the result of the glaze tub, or of the brush. Occasionally also a very fusible composition is thrown upon the inner surface of the muflSe, and 5 or 6 pieces called refractories are set in the middle of it, coated with the same composition. The intensity of the heat converts the flux into vapor; a part of 6P this is condensed upon the surfaces of the contiguous articles ; so as to give them the de- tired brilliancy. « - , , « r -i « i i ^r Mortar body is a paste composed of 6 parts of clay, 3 of feldspar, 2 of silex, and 1 of ^ While^and yellow fisures upon dark-colored grounds are a good deal employed. Tc produce yellow impressions upon brown stoneware, ochre is ground up with a small quantity of antimony. The flux consists of flint glass and flints m equal weights. The composition for white desi-ns is made by grinding silex up with that flux, and print- ing it on, as for blue colors, upon brown or other colored stoneware, which shows od the li^'ht hifs "EngUsh porcelain or china.-Mosi of this belongs to the class called tender or soft por- celain by the French and German manufacturers. It is not, therefore, composed simply of kaolin and petuntse. The English china is e:enerally baked at a much lower heat than that of Sivres, Dresden, and Berlin; and it is covered with a mere glass Being inanu- factured upon a prodigious scale, with great economy and certainty, and little expenditure of fuel, it is sold at a very moderate price compared with the foreign porcelain, and in external appearance is now not much inferior. rr.u- • a Some of the En-lish porcelain has been called ironstone china. This is composed usu- ally of 60 parts of Cornish stone, 40 of china clay, and 2 of A^t glass ; or of 42 of the feldspar, the same quantity of clay, 10 parts of flints ground, and 8 of Aint glass The ^laze for the first composition is made with 20 parts of feldspar, 15 of flints, 6 of red leal, and 5 of soda, which are fritted together; with 44 parts of the frit, 22 parts of flint slass, and 15 parts of white lead, are ground. rn- ♦ i c qa «r foUc««r The glaze for the second composition is formed of 8 parts of flint glass, 36 of feldspar, 40ofwhitelead, and 20 of silex (ground flints.) . . r ., i • k- The En-lish manufacturers employ three sorts of compositions for the porcelain bis- cuit; namely, two compositions not fritted; one of them for the ordinary table sernce; another for the dessert service and tea dishes; the third, which is fritted corresponds to the paste used in France for sculpture ; and with it all delicate kinds of ornaments are made. Ground flints ■ Calcined bones China clay Clav First composition. 75 180 40 70 Second compisition. I Third composition. Granite 66 100 96 80 Lynn sand 150 - 300 - 100 Potash - 10 The ^laze for the first two of the preceding compositions consists of, feldspar 45, flmls 9, borax 21, flint class 20, nickel 4. After fritting that mixture, add 12 parts of red lead For the third composition, which is the most fusible, the glaze must receive 12 parts of ground flints, instead of 9 ; and there should be only 15 parts of borax, instead of 21. PLAN OF AN ENGLISH POTTERY. A Stoneware manufactory should be placed by the side of a canal or navigable river, because the articles manufa'ctured do not well bear land carriage. A Slaff'ordshire pottery is usually built as a quadrangle, each side being about 100 feel lon<' the walls 10 feet hieh, and the ridge of the roof 5 feet more. The base of the edi- fice'^consists of a bed of bricks, 18 inches high, and 16 inches thick; upon which a mud wall in a wooden frame, called pise, is raised. Cellars are formed m front of the build- ings, as depots for the pastes prepared in the establishment. The wall of the yard or court is 9 feet high, aa 18 inches thick. ^ ii'tg. 1156 A, is the entrance door ; b, the porter's lodge; c, a particular warehousej D, workshop of the plaster-moulder- -., me clay depot; f, f, large gates, 6 feet 8 inches hi<'h ; G, the winter evaporation stove ; h, the shop for sifting the paste liquors ; i, sheds for the paste liquor tubs; J, paste liquor pits; k, workshop for the moulder of hcllow ware ; l, ditto of the dish or plate moulder ; m, the plate drying-stove ; n, workshop oi the biscuit-printers; o, ditto of the biscuit, with o', a long window ; p, passage leading to the paste liquor pits ; q, biscuit warehouse; r, place where the biscuit is cleaned as it comes GUI of the biscuit-kilns, s, s ; t, t, enamel or glaze-kilns ; u, long passage ; v, space left for supplementarv workshops ; x space appointed as a depot for the sagger fire-clay, as also for making the saggers; z, ihe workshop for applying the glaze liquor to the biscuits ; a apartment for cleaning the glazed ware ; b, b, pumps ; c, basin ; d, muffies ; «, ware- house for the finished stoneware; /, that of the glazed goods ; g, g, another warehouse , k a lar^e space for the smith's forge, carpenter's shop, packing room, depot of clays, sL', instead ol the hand. A vertical shaft, with horizontal or oblique paddles, is made to revolve in the vaU for this purpose. , ... • j- _ The small triturating tpAU is represented in fig. 1158, There are three similar fi'^ding- tubs on the same line. The details of the construction are shown in figs. 11^9, 60. where it is seen to consist principally of a revolving millstone a (yig. 1169) of a last or sleeper millstone b', and of a vat c, hooped with iron, with its top raised above the upper millstone. The lower block of hornstone rests upon a very firm basis, 6 ; il is surrounded immediately by the strong wooden circle c, which slopes out funnel-wise above, in order to throw back the earthy matters as they are pushed up by the attrition POTTERY. 481 1159 •f the stones. That piece is hollowed out, partially to admit the key c, opposite to which is the faucet and spigot c', for emptying the tub. When one operation is com- pleted, the key c is lifted out by means of a peg put into the holes at its top ; the spigot it then drawn, and the thin paste is run out into vats. The upper grindstone, b d, like the lower one, is about two feet in diameter, and must be cut in a peculiar manner. At first there is scooped out a hollowing in the form of a sector, denoted b) d ^fyfig'^l^O ; the arc d/ is about one sixth of the circumference, so that the vacuity of the turning grindstone is one sixth of its surface ; moreover, the stone must be channelled, in order to grind or crush the hard gritty substances. For this purpose, a wedge-shaped groove d e g, about an inch and a quarter deep, is made on its under face, whereby the stone, as it turns in the direc- wm/mm/M. tion indicated by the arrow, acts with this inclined plane upon all the particles in its course, crushing them and forcing them in between the stones, till they be tritur\ted to an impalpable powder. When the grindstone wears unequally on its lower surface, it ii useful to trace upon it little furrows, proceeding from the centre to the circumference, like those shown by the dotted lines c' t". It must, moreover, be indented with rough points by the hammer. The turning horn-stone block is set in motion by the vertical shaft h, which is fixed by the clamp-iron cross i to the top of the stone. When the stone is new, its thickness is about 14 inches, and it is made to answer for grinding till it be reduced to about 8 inches, by lowering the clamp i upon the shaft, so that it may continue to keep its hold of the stone. The manner in which the grindstones are turned, is obvious from inspection of ^g. 1168 where the horizontal axis l, which receives its impulsion from the great water-wheel, turns the prolonged shaft l', or leaves it at rest, according as the clutch /, r, is locked or opened. This second shaft bears the three bevel wheels m, m, m. These work in three corresponding bevel wheels m' m' m', made fast respectively to the three vertical shafts of the millstones, which pass through the cast iron guide tubes m" m". These are fixed in a truly vertical position by the collar- bar m", m\fig. 1159. In this figure we see at m how the strong cross-bar of cast iron is made fast to the wooden beams which support all the upper mechan- ism of the mill-work. The bearing m' is disposed in an analogous manner ; but it is supported against two cast iron columns, shown at l" l", in ^g. 1168 The guide tubes m" are bored smooth for a small distance from each of their extremities, and their interjacent calibre is wider, so that the vertical shafts touch only at two places. It is obvious, that when- ever the shaft l' is set a-going, it necessarily turns the wheels m and m', and their guide tubes m"; but the vertical shaft may remain either at rest, or revolve, according to the position of the lever click or catch K, at the top, which is made to slide upon the shaft, and can let fall a finger into a vertical groove cut in the surface of that shaft. The clamp-fork of the click is thus made to catch upon the horizontal bevel- wheel m', or to release it, according as the lev^r k is lowered or lifted up. Thus each millstone may be thrown out of or into gear at pleasure. These stones make upon an average 11 or 12 turns in a minute, corresponding to three revolutions of the water- wheel, which moves through a space of 3 feet 4 inches in the second, its outer circumference being 66 feet. The weight of the upper stone, with its iron mountings, u about 6 cwts., when new. The charge of each mill in dry material is 2 cwts. ; and the water may be estimated at from one half to the whole of this weight ; whence the total load may be reckoned to be at least 3 cwts. ; the stone, by displacement of the magma, loses fully 400 pounds of its weight, and weighs therefore in reality only 2 cwts. It is charged in successive portions, but it is discharged all at once. When the grinding of the silicious or feldspar matters is nearly complete, a remarkable Vol. IL 3 Q 482 POTTERY. POTTERY. 483 phenomenon occurs ; the substance precipitates to the bottom, and assumes in a few seconds so strong a degree of cohesion, that it is haidly possible to restore it again to the pasty or mamga state; hence if a millstone turns too slowly, or if it be accidentally stopped for a few minutes, the upper stone gets so firmly cemented to the under one, that it is difficult to separate them. It has been discovered, but without knowing why, that a little vinegar added to the water of the magma almost infallibly prevents that sudden stiffening of the deposite and stoppage of the stones. If the mills come to be set fast in this way, the shafts or gearing would be certainly broken, were not some safety provision to be made in the machinery against such accidents. Mr. Hall's con- trivance to obviate the above danger is highly ingenious. The clutch /, /',^^. 1158is not a locking ciab, fixed in the common way, upon the shaft l; but it is composed as ''''" "''' shown in^^j. 1161, 62, 63, 64., of a hoop t*, fixed upon the shaft by means of a key, of a collar r, and of a flat ring or washer x, with four projections, which are fitted to the collar r, by four bolts y. Fig. 1162 represents the collar v seen in front ; that is, by the face which carries the clutch teeth ; and^g.1163 rep- resents its other face, which receives the flat ring ar, fig. 1 164 in four notches corresponding to the four pro- jections of the washer-ring. £ince the ring u is fixeil upon the shaft l, and necessarily turns with it, it has the two other pieces at its disposal, namely, the collar , ^^ t?, and the washer X, because they are always connected with It by the four bolts y, so as to turn with the ring 7*, when the resistance they encounter upon the shaft l' is not too great, and to remain at rest, letting the ring u turn by itself, when that resistance increases to a certain pilch. To give this degree of friction, we need only interpose the leather washers z, z',fig. 1161. and now as \i-.<> collar coupling, box, V, slides pretty freely upon the ring «, it is obvious that by tightening more or less the screw bolts y, these washers will become as it were a lateral brake, to lighten more or less the bearing of the ring m, to which thev are applied ; by regulating this pressure, everything may be easily adjusted. When the resistance becomes too great, the leather washers, pressed upon one side by the collar r, of the washer 4-, and rubbed upon the other side by the prominence of the ring n, get heated to such a degree, that they are apt to become carbonized, and require replacement. This safety clutch may be recommended to the notice of mechanicians, as susceptible of beneficial application in a variety of circumstances. GREAT PORCELAIN MILL, The large feldspar and kaolin mill, made by Mr. Hall, for Sevres, has a flat bed of hornstone, in one block, laid at the bottom of a great tub, hooped strongly with iron. In most of the English potteries, however, that bed consists of several flat pieces of chert or hornstone, laid level with each other. There are, as usual, a spigot and faucet at the side, for drawing off the liquid paste. The whole system of the mechanism is very sub- stantial, and is supported by wooden beams. The following is the manner of turning the upper blocks. In ^g. 1157 the main horizontal shaft p bears at one of its extremities a toothed wheel, usually mounted upon 1166 the periphery of the great water-wheel (yig. 1165. shows this toothed wheel by a dotted line) at its other end; p car- ries the fixed portion p of b, coupling-box, similar to the one just described as belonging to the little mill. On the pro- longation of p, there is a second shaft p', which bears the move- able portion of that box, and an upright bevel wheel p" Lastly, in figs. 1161 and 1165 there is shown the vertical shaft Q, which carries at its upper end a large horizontaj ., . . , .^ . 1 -.I.- , cast-iron wheel q', not seen in this view, because 1 is sunk withm the upper surface of the turning hornstone, like the clamp d,f,mfig. 1159. At the lower end of the shaft q, there is the bevel wheel o'\ Fhich receives motion from the wheel f",fig. 1157. ; The shaft p always revolves with the water-wheel j but transmits its motion to the shaft p' only when the latter is thrown into gear with the coupling-box /)', by means of its forked lever. Then the bevel wheel p' turns round with the shaft p', and communicatei its rotation to the bevel wheel q", which transmits it to the shaft Q, and to the large cast iron wheel, which is sunk into the upper surface of the revolving hornstone. The shaft q is supported and centred by a simple and solid adjustment ; at its lower part, it rests in a step r', which is supported upon a cast-iron arch q', seen in profile in fig. 1167. its base is solidly fixed by four strong bolts. Four set screws above R,/g.ll57 serve to set the shaft q truly perpendicular ; thus supported, and held securely at its lower end, in the step at B.,figs. 1157 & 1166 it is embraced near the upper end by a brass bush or collar, composed of two pieces, which moy be drawn closer together by means of a screw. This collar is set into the summit of a great truncated cone of cast-iron, which rises within the tub through two thirds of the thickness of the hornslone bed; having its base firmly fixed by bolts to the bottom of the tub, and having a brass collet to secure its top. The iron cone is cased in wood. When all these pieces are well adjusted and properly screwed up, the shaft q revolves without the least vacillation, and carries round with it the large iron wheel q', cast in one piece, and which consists of an outer rim, three arms or radii, and a strong central nave, made fast by a key to the top of the shaft q, and resting upon a shoulder nicely turned to receive it. Upon each of the three arms, there are adjusted, with bolts, three upright substantial bars of oak, which descend vertically through the body of the revolving mill to within a small distance of the bed-stone ; and upon each of the three arcs of that wheel-ring, comprised between its three strong arms, there are adjusted, in like manner, five similar uprights, which fit into hollows cut in the periphery of the moving stone. They ought to be cut to a level at their lower part, to suit the slope of the bottom of the tub o,figs. 1157 & 1165 so as to glide past it pretty closely, without touching. The speed of this large mill is eight revolutions in the minute. The turning horn- stone describes a mean circumference of 141^ inches (its diameter being 45 inches), and of course moves through about 100 feet per second. The tub o, is 52 inches wide at bottom, 56 at the surface of the sleeper block (which is 16 inches thick), and 64 at top, inside measure. It sometimes happens that the millstone throws the pastj' mixture out of the vessel, though its top is 6 inches under the lip of the tub o; an inconvenience which can be obviated only by making the pap a little thicker ; that is, by allowing only from 25 to 30 per cent, of water ; then its density becomes nearly equal to 2*00, while that of the millstones themselves is only 2*7 ; whence, supposing them to weigh only 2 cwts., there would remain an effective weight of less than \ cwt. for pressing upon the bottom and grinding the granular particles. This weight appears to be somewhat too small to do much work in a short time ; and therefore it would be better to increase the quantity of water, and put covers of some convenient form over the tubs. It is estimated that this mill will grind nearly 5 cwts. of hard kaolin or feldspar gravel, in 24 hours, into a proper pap. To the preceding methodical account of the porcelain manufacture, I shall now sub- join some practical details relative to certain styles of work, with comparisons between the methods pursued in this country and upon the Continent, but chiefly by our jealous rivals the French. The blue printed ware of England has been hitherto a hopeless object of emulation in France. M. Alexandre Brongniart, membre de I'Institut, and director of the Manvfaciure Royal de Sevres, characterizes the French imitations of the Fayence fine, ou ^nglaise, in the following terms : " Les defa-Jts de cette poterie, qui tiennent a sa nature, sonl de ne pouvoir aller sur le feu pour les usages domestiques, et d'avoir un vemis tendre, qui se laisse aisement entamer par les instruments d'acier et de fer. Mais lorsque cette poterie est mal fabriquee, ou fabriquee avec une economic mal entendue, ses defauts deviennenl bien plus graves ; son vemis jaunatre et tendre tressaille souvent ; il se laisse entamer ou user avec la plus grande facilite par les instruments de fer, oupar I'usage ordinaire. Les fissures que ce tressaillement ou ces rayures ouvrent dans le vernis permettent aux matieres grasses de penetrer dans le biscuit, que dans les poteries affectees de ce defaut, a presque toujours une texture lache ; les pieces se salissent, s'empuantissent, et se brisent meme avec la plus grande facilite."* What a slaze, to be scratched or grooved with soft iron ; to fly oflT in scales, so as to let grease soak into the biscuit or body of the ware; to become foul, stink, and break with the utmost ease ! The refuse crockery of the coarsest pottery works in the United King- dom would hardly deserve such censure. In the minutes of evidence of the Enquete MinistMiUe, published in 1835, MM. de Saint Cricq and Lebeuf, large manufacturers of pottery-ware at Creil and Montereau, give a very gratifying account of the English stoneware manufacture. They declare that the Eng- lish possess magnificent mines of potter's clay, many leagues in extent ; while those of the * Diet. Technologique, torn, xrii., article Poteries, p 1U3. 484 POTTERY. I.' «1 French are mere patches or pots. Besides, England, they say, having upwards of 20C potteries, can constantly employ a great many public flint-mills, and thereby obtain thai indispensable material of the best quality, and at the lowest rate. « The mill erected by M. Brongniart, at Sdvres, does its work at twice the price of the English mills The fuel costs in England one fourth of what it does in France. The expense of a kiln-round m the latter country, is 200 francs ; while in the former it is not more than 60 " AAer a two-months tour among the English potteries, these gentlemen made the followine ad- ditional observations to their first official statement :— "The clay, which goes by water carriage from the counties of Devon and Dorset into Staffordshire, to supply more than 200 potteries, clustered together, is delivered to them at a cost of 4 francs (3*. 2d.) the 100 kilosrrammes (2 cwt.) ; at Creil, it costs 4f 50c and at Mintereau, only 2/. 40c. There appears, therefore, to be no essential difference m the price of the clay; but the quality of the English is much superior, being inqon- testably whiter, purer, more homogeneous, and not turning red at a hi^h heat like the French.'' The grinding of the flints costs the English potter 4*^/. per 100 kilos.', and the French 6d. ; but as that of the latter is in general ground dry, it is a coarser article. The kaolin, or chma clay, is imported from Cornwall for the use of many French potteries • but the transport of merchandise is so ill managed in France, that while 2 cwts. cost in Staflordshire only 8/. 7oc. (about 7*. Id.), they cost 12/. at Creil, and 13/. 50c. al Montereau. The white lead and massicot, so much employed for elazes, are 62 per cent dearer to the French potters than the English. As no French mill has succeeded in making unsized paper fit for printing upon stoneware, our potters are under the necessity of fetching it from England ; and, under favor of our own custom-house, are allowed to import it at a duty of 165/ per 100 kilogrammes, or about 8rf. per pound iLnghsh. No large stock of materials need be kept by the English, because everr *''^-**^ !.T^ ^^^ ^^^" wanted from its appropriate wholesale dealers ; but the case is quite different with the French, whose stocks, even in small works, can never safely be less m value than 150,000/ or 200,000/ ; constituting a loss to them, in interest upon their capital, of from 7,500/ to 10,000/ per annum. The capital sunk in buildin^ris lar less in England than in France, in consequence of the different stvles of erectino- stone- ware factories in the two countries. M. de Saint Cricq informs us,' that Mr. Clewes of bhelton, rents his works for 10,000/ (380/.) per annum; while thfe similar ones of Creil and Montereau, m France, have cost each a capital outlay of from 500,000/ to 600 000/* and in which the products are not more than one half of Mr. Clewes'. « This forms a balance against us," says M. St. C, "of about 20,000/ per annum; or nearly 800/ sterling. Finally, we have the most formidable rival to our potteries in the extreme dexterity of the English artisans. An enormous fabrication permits the manufacturers to employ the same workmen during the whole year upon the same piece ; thus I have seen at Shelton a furnisher, for sixpence, turn off 100 pieces, which cost at Creil and Montereau 30 sous (1*. 2^d.) ; yet the English workman cams 18/ 75c. a week, while the French never earns more than 15/ I have likewise seen an English moulder expert enough to make 25 waterpots a day, which, at the rate of 2d. a piece, brin*- him 4*. 2d. of daily wages; while the French moulder, at daily wages also of 4*. 2d "turns out of his hands only 7, or at most 8 pots. In regard to hollow wares, the English may be fairly allowed to have an advantage over us, in the cost of labor, of 100 per cent • which they derive from the circumstance, that there are in Staffordshire 60,000 operatives* men, women, and children, entirely dedicated to the stoneware manufacture ; concentra' ting all their energies within a space of 10 square leagues. Hence a most auspicious choice ol good practical potters, which cannot be found in France." M. Saint Amans, a French gentleman, whp spent some years in Staffordshire, and has lately erected a large pottery in France, says the English surpass all other nations in manufacturing a peculiar stoneware, remarkable for its lightness, strength, and ele<'ance- as also m printing blue figures upon it of every tint, equal to that of the Chinese by processes of singular facility and promptitude. After the biscuit is taken out of 'the kiln, the fresh impression of the engraving is transferred to it from thin unsized paper previously immersed in strong soap water ; the ink for this purpose being a compound of arseniate of cobalt with a flux, ground up with properly boiled linseed oil The copper-plates are formed by the graving tool with deeper or shallower lines, according' to the variable depth of shades in the design. The cobalt pigment, on meltine, spreads" so as to give the soft effect of water^iolor drawing. The paper, being still moist, is readily applied to the slightly rough and adhesive surface of the biscuit, and may be rubbed on more closely by a dossil of flannel. The piece is then dipped in a tub of water whereby the paper gets soft, and may be easily removed, leaving upon the pottery the pig- ment of the engraved impression. After being gently dried, the piece is dipped into the glaze mixture, and put into the enamel oven. POTTER'S OVEN. 285 Composition of the Earthy Mixtures, The basis of the English stoneware is, as formerly stated, a bluish clay, brought from Dorsetshire and Devonshire, which lies at the depth of from 25 to 30 feet beneath tYie surface. It is composed of about 24 parts of alumina, and 76 of silica, with some other ingredients in very small proportions. This clay is very refractory in high heats, a pro- perty which, joined to its whiteness when burned, renders it peculiarly valuable for pot- tery. It is also the basis of all the yellow biscuit-ware called cream color , and in general of what is called the printing body ; as also for the semi-vitiified porcelain of Wedgewood's invention, and of the tender porcelain. The constituents of the stoneware are, that clay, the powder of calcined flints, and of the decomposed feldspar called Cornish stone. The proportions are varied by the difl'erenc manufacturers. The following are those generally adopted in one of the principal estab- lishments of Staffordshire : — For cream color, Silex or ground flints ------ 20 parts Clay 100 Cornish stone ---.---2 Composition of the Paste for receiving the Printing Body under the Glaze. For this purpose the proportions of the flint and the feldspar must be increased. The substances are mixed separately with water into the consistence of a thick cream, which weighs per pint, for the flints 32 ounces, and for the Cornish stone 28. The china clay of Cornwall is added to the same mixture of flint and feldspar, when a finer pottery or porcelain is required. That clay cream weighs 24 ounces per pint. These 24 ounces in weight are reduced to one third of their bulk by evaporation. The pint of dry Cornish clay weighs 17 ounces, and in its first pasty state 24, as just stated. The dry flint powder weighs 14^ ounces per pint ; which when made into a cream weighs 32 ounces. To 40 measures of Devonshire clay-cream there are added, 13 measures of flint liquor. 12 — Cornish clay ditto. 1 — Cornish stone ditto. The whole are well mixed by proper agitation, half dried in the troughs of the slip-kiln, and then subjected to the machine for cutting up the clay into junks. The above paste, when baked, is very white, hard, sonorous, and susceptible of receiving all sorts of im- pressions from the paper engravings. When the silica is mixed with the alumina in the above proportions, it forms a compact ware, and the impression remains fixed between the biscuit and the glaze, without communicating to either any portion of the tint of the me- tallic color employed in the engraver's press. The feldspar gives strength to the biscuit, and renders it sonorous after being baked ; while the china clay has the double advantagt of imparting an agreeable whiteness and great closeness of grain. Dead silver on porcelain is much more easily affected by fuliginous vapours than burnished. It may, however, by the following process be completely protected. The silver must be dissolved in very dilute acid, and slowly precipitated ; and the metallic precipitate well washed. The silver is then laid (in wavy lines?) upon the porcelain pefore being coloured (or if coloured, the colour must not be any preparation of gold) in a pasty state and left for 24 hours, at the expiration of which time the gold is to be laid on and the article placed in a moderate heat The layer of gold must be very thin, and laid on with a brush over the silver before firing it ; when by the aid of a flux and a cherry red heat the two metals are fixed on the porcelain. — NewtorCs Journal, xxxL 128. POTTER'S OVEN. A patent was obtained in August, 1842, by Mr. W. Ridgway for the following construction of oven, in which the flames from the fireplaces are conveyed by parallel flues, both horizontal and vertical, so as to reverberate the whole of the flame and heat upon th6 goods after its ascension from the flues. His oven is built square instead of round, a fire-proof partition wall being built across the middle of it, dividing it into two chambers, which are covered in by two parallel arches. The fireplaces are built in the two sides of the oven opposite to the partition wall; from which fireplaces narrow flues rise in the inner face of the wall, and distribute the flame in a sheet equally over the whole of its surface. The other portion of the heat is conveyed by many parallel or diverging horizontal flues, under and across the floor or hearth of the oven, to the middle or partition wall ; over the surface of which the flame which ascends from the numerous flues in immediate contact with the wall is equally distributed. This sheet of ascending flame strikes the shoulder of the arch, and is reverberated from the seggars beneath, till it meets the flame reverberated from the opposite side of the arch, and both escape at the top of the oven. The same con- struction is also applied to the opposite chamber. In figs, 1166, 67, a, represents the f r 486 PRESS. HYDRAULia I' ,;l 1166 1167 square walls or body of the oven ; b, the partition wall ; c, the fireplaces or fum»cea with their iron boilers ; d, the mouths of the furnaces for introducing the fuel ; /, Ihc ash-pits; g, the horizontal flues under the hearth of the oven; h, the vertical flues; i, the vents in the top of the arches ; and k, the entrances to the chambers of the ovens. PRECIPITATE, is any matter separated in minute particles from the bosom of a fluid, which subsides to the bottom of the vessel in a pulverulent form. PRECIPITATION, is the actual subsidence of a precipitate. PRESS, HYDRAULIC. Though the explanation of the principles of this power- ful machine belongs to a work upon mechanical engineering, ratlier than to one upon 1168 1169 ^ manufactures, yet as it is often referred to in this volume, a brief description of it caz^ not be unacceptable to many of my readers. The framing consists of two stout cast-iron plates a, b, which are strengthened by pro- jecting ribs, not seen in the section, Jl^. 1168. The top or crown plate 6, and the base- plate a, a, are bound most firmly together by 4 cylinders of the best wrought iron, plication to various fabrics. But since chemistry has been allowed to occupy a part of the atten- tion of the manufacturer, a very different result has arisen. The indications of expe- rience are confirmed by the teachings of philosophy, and in a large number of instances a vast economy of material, time and labour has been effected. In addition, chemistry has brought to light new compounds and new means of obtaining dyes and colours of great brilliance from a few simple combinations. It is consequently now almost uni- versal to find that attached to the extensive works of the dyer and colour-printer is a large laboratory fitted up for chemical investigations, and the processes developed in which are often the source of a very great commercial prosperity'. The print works of Lancashire, and particularly of Manchester and its vicinity, form the most extensive sources of printed and dyed articles. Glasgow, Carlisle, Crayford, Paisle}^ and other places, also contain important works of a somewhat similar descrip- tion. The origin of cotton printing appears to have taken place in the vicinity of the metropolis in 1675. During the last half century, a surprising development of printing in colour and dyeing has taken place. It is estimated that^ at its commencement, the annual quantity of cotton printed was 32,869,729 yards. But in 1830, this quantity had attained the enormous increase of 347,450,299 yards; and it has since still further increased. Th« print works of Lancashire, and other places, form a surprising spectacle of the operation of chemical and mechanical forces on the great scale. That which was formerly the labour of weeks is now performed in a day. A piece of cloth is printed at the rate of hundreds of yards in a day. On one side of a machine-room it ascends moist, with colour from the engraved copper c^'linder ; on the other hand it descends dried, ready for the final processes. The printing machines are marvels of ingenuity ; the pattern is applied by the engraved surface of one or more copper cylinders, which have received the pattern from a small steel cylinder, or " mill " capable of impressing several witb the same design, and thus saving the cost of repeated engraving. At firgt only one colour could be applied ; now from six, or even eight and ten colours are applied in constant succession. These machines perform their work with great accuracy and speed, and produce all the commoner patterns seen in daily use ; but hand labour is still employed, even in these works, for fine or complicated work, and more particularly for printing mousseline-de-laine dresses, foreign countries a certain peculiarity of chromatic arrangement is necessary in order to render the articles adapted to the taste of purchasers. The art of the dyer in towns is a manufacture on a smaller scale, and carried on gene- rally in small establishments devoted to that purpose. But extensive dye-works exist, which are employed in imparting various colours to cloth, Ac, on the great scale To the prosperous pursuit of either of these arts it is beginning to be more and more ■widely felt that an enlightened and philosophical mind is of the first consequence Formerly the application of coloured designs to fabrics of various kinds was entirely eflFected by what is called block-printing, and which in fact clr°r^ approxinjating to a natural bllsam, like that of CanadaTwhiSi isll^ one of the best varnishes that can be used for printing ink. ' ^ 6. aoap.^lbis is a most important ingredient in printers' ink, which is not even mentioned m any of the recipes prior to%hat in the Encycloi^irBritannica To? Tn «ftpr T^' »"k a<^c«mulates upon the face of the types, so as^pletely to^W the« alkaHne e."Tnd I't s'kfn:'^"'""""' '^-^^ *^^^" ^^^ ' '' ""^ -' wasVoffTitho^ aiKaiine lejs, and it skins over very soon in the pot. Yellow rosin soao is thp hf»^t far blackinksj for those of light and delicate shadesfwhite curd soaTinrefLable T^ r^tl'^^^^Ti^ ^^' '"'""^"^ '^^ ^'"P^ession irregular, and to prevenrtheink7^^^^^ n4; ;^dT^:ts7o?ra^^^ '^- ^^ '- ^'^ -- - a. Ivory black is too heavy to be used alone as a pigment for i^rinting ink • but it mav be added with advantage by grinding a little of it upon a muller X the lamp black foJ ♦oif* ^"f^u ^I?'"''' "'* "^'^^ *" ^"1"*^ ^^^§^^ of Prussian blue, added in small nronortion takes off he brown tone of certain lamp black inks. Mr. Savage JecommeE7i^t?; Ir^dian r.d to be ground in with the indigo and Prussian blue, to'|wrrrTch?oirti^lh: hvl' cf '''*'''" f ''"^T' *^ ^^^ ^y ^^- A^^e»' Plough-court, Lombard-street mixed, by a stone and a muller, with a due proportion of soap and pigment forms an ^tem poraneous ink, which the printer may employ Very ad?antageoSsl whenTe 4he8 To" execute a job m a peculiarly neat manner, Canada balsam does^ofLswerquUe 12 fKA^fn *^^ "f"^^ ^^^'J"^ *** ""^ ^^**" ^^^ ^«i^i"8^ «'^ a bit of burning paper stuck in he cleft end of a long stick should be applied to the su/face, to set it on fire asl^on ^^ the vapor will burn; and the flame should be allowed to continue (the StXi^ r^r rn''"'^'^'!^'^"', 7^' '^^ fi^^'O-- '^^^'^ t^ken from under the p^ ml fn^ K ^ """"'"''t T^^ "P^'* * pallet-knife, draws out into strings of about ha^ a? inch long between the fingers. To six quarts of linseed oil thus treated six oound. nf rosin should be gradually added, as soon as the froth of the eLmdon hTs ^^^^^^^^^^ Whenever the rosm is dissolved, one pound and three quarters of dry brown soap of t1?« best quality cut into slices, is to be introduced cautiously, for its waterT cZbina Jn^ causes a v^lent intumescence. Both the rosin and soap should be wdl sUrred^ih £e Kl^ionltStle^nr " '^ "^" ''' "^^'^ ''^ ^^^' ^ ^^^ ^« complete tllo^finllSn^? Put next of well ground indigo and Prussian Whp pnnh 91 «»«/.«« • . sufficiently large toLld aU .he^„k.ar„*„"grhipl\tof^^^^^^ «d 3J pounds of good vegelable lamp black; then add the wLm T«nTsh b^oTde^ree/ carefally sUrnng, to produce a perfect incorporation of all the ingre^ents ThTs mS redydc. ^"iwerp oiue, lustie, umber, sepia, browns mixed with Venetian Int'^S'lho'^^^^^^^^ -^'--r' ^'-^ ^-^ckmaschine, Germ.) ^r^orirksl: v^^^^^^^^^ ^h- P^'-l-tive arts, aft^r a long S matter, the contemplative mind can^^^^^^^ some new conquest over the inertia which the'academical philosopher has generS^lnlLj^J^^^ T^ '^^^ insignificant part Eno'rossed with hnriPn Jiw; gen eraUy played m such memorable events. ,rufsrKlisTute';r„\vtfe'MieTsr"the t^^^t' "'^ ""."'>"" «»" disdains to soil his hands with th<«?hSS onl,^,?! . k°[ n ?""'"»««s. """l the arts must necessarily beein. He does It de?m^ - r "^'"^ *" "nprovements i. unit has worked out its own granderand ?„H.^„ r"*^*' !!" "^""^^ .ummate skill. In this spirit thrmerof"„ec,?I»rrl!-" "'"* r^SV'*'"'' *"'' '^• rteamen^neof Newcomen%i:ithc"trsa„ZtUmr^^^^^^^ "^^'^"^ ^'" ^ ^'"?"'" .hey have^never deigned to illustrate br£a^lc:;i-tSf,rs'rf:rrr;:^ I .r., fj ■ 490 PRINTING MACHINE. of Aikwright, yet nothing in the whole compass of art deserves it so well ; and though perfectly aware that revolvency is the leading law in the system of the universe, they have never thought of showing the workman that this was also the true principle of every automatic machine. These remarks seem to be peculiarly applicable to book-printing, an art invented for the honor of learning and the glory of the learned, though they have done nothing for its advancement ; yet by the overruling bounty of Providence it has eventually served as the great teacher and guardian of the whole family of man. It has been justly observed by Mr. Cowper, in his ingenious lecture,* that no improve- ment had been introduced in this important art, from its invention till the year 1798, a period of nearly 350 years. In Dr. Dibdin's interesting account of printing, in the Bibliographical Decameron, may be seen representations of the early printing-presses, which exactly resemble the wooden presses in use at the present day. A new era has, however, now arrived, when the demands for prompt circulation of political intelligence require powers of printing newspapers beyond the reach of the most expeditious hand press work. For the first essential modification of the old press, the world is indebted to the late Earl Stanhope, f His press is formed of iron, without any wood ; the table upon which the form of types is laid, as well as the platen or surface which immediately gives the impression, is of cast iron, made perfectly level ; the platen being large enough to print a whole sheet at one pull. The compression is applied by a beautiful combination of levers, which give motion to the screw, cause the platen to descend with progressively increasing force till it reaches the type, when the power approaches the maximum ; upon the infinite lever principle, the power being applied to straighten an obtuse-angled jointed lever. This press, however, like all its flat-faced predecessors, does not act by a continuous, but a reciprocating motion, and can hardly be made automatic ; nor does it much exceed the old presses in productiveness, since it can turn ofl' only 250 impressions per hour. The first person who publicly projected a self-acting printing-press, was Mr, William Nicholson, the able editor of the Philosophical Journal, who obtained a patent in 1790-1, for imposing types upon a cylindrical surface; this disposition of types, plates, and blocks, being a new invention (see Jig. 1172.); 2, for applying the ink upon the surface of the types, &c., by causing the surface of a cylinder smeared with the coloring-matter to roll over them ; or else causing the types to apply themselves to the said cylinder. For the purpose of spreading the ink evenly over this cylinder, he 11Y2 proposed to apply three or more distributing rollers longitudinally against the inking cy- linder, so that they might be turned by the motion of the latter. 3. " I perform," he says, "all my impressions by the action of a cylinder, or cylindrical surface; that is, I cause the paper to pass between two cylinders, one of which has the form of types attached to it, and forming part of its surface; and the other is faced with cloth, and serves to Nicholson's for Nicholson's for press the paper SO as to take oflT an impres- archedtyi>e. common type. sion of the color previously applied; or otherwise I cause the form of types, previously colored, to pass in close and successive contact with the paper wrapped round a cylinder with woollen." rSee fies. 1172 and 1173.)$ V ^6 In this description Mr. Nicholson indicates pretty plainly the principal parts of modern printing machines ; and had he paid the same attention to any one part of his invention which he fruitlessly bestowed upon attempts to attach types to a cylinder, or had he bethought himself of curving stereotype plates, which were then beginning to be talked of, he would in all probability have realized a working apparatus, instead of scheming merely ideal i)lans. The first operative printing machine was undoubtedly contrived by, and constructed under the direction of, M. KOnig, a clockmaker from Saxony, who, so early as the year 1804, was occupied in improving printing-presses. Having failed to interest the con- tinental printers in his views, he came to London soon after that period, and submitted his plans to Mr. T. Bensley, our celebrated printer, and to Mr. R. Taylor, now one of tke editors of the Philosophical Magazine. ♦ On the recent improvements in printini?. first delivered at the Royal Institution, February 22, 182b 1 If d Stanhope is the only man of learning whose name figures in the annals of typography. t The black parts in these httle diagrams, 913—922, indicate the inking apparatus ,- the diagonal lines tha ^rlinders upon which the paper to be printed is applied ; the perpendicular lines, the plates or types • «iid the arrow* show the track pursued by the sheet of paper. PRINTING MACHINJK. 4M These gentlemen afforded Mr. Konig and his assistant Bauer, a German mechanic, liberal pecuniary support. In 181 1, he obtained a patent for a method of working a com- mon hand-press by power; but after much expense and labor he was glad to renounce the scheme. He then turned his mind to the use of a cylinder for communicating the pressure, instead of a flat plate; and he finally succeeded, some time before the 28th No- Tember, 1814, in completing his printing automaton ; for on that day the editors of the Times informed their readers that they were perusing for the first time a newspaper print- ed by steam-impelled machinery ; it is a day, therefore, which wUl be ever memorable ia the annals of typography. In that machine the form of type was made to traverse horizontally under the pressure cylinder, with which the sheet of paper was held in close embrace by means of a series fljhj^ of endless tapes. The ink was placed in a cylindrical box, ^ from which it was extnided by means of a powerful screw, de- ^^ ^f pressing a well-fitted piston; it then fell between two iron ^1L /^S^ rollers, and was by their rotation transferred to several other • • WmAk^ subjacent rollers, which had not only a motion round their w"© ^^P^ ^^^^'^ ^"* ^"^ alternating traverse motion (endwise). This Limrnii system of equalizing rollers terminated in two which applied Konig's single, for one the ink to the types. (See^g. 1174.) This plan of inking evi- side of tho sheet. dently involved a rather complex mechanism, was hence diflSicult to manage, and sometimes required two hours to get into good working trim. It has been superseded by a happy invention of Mr. Cowper, to be presently described. In order to obtain a great many impressions rapidly from the same form, a paper-con- ducting cylinder (one embraced by the paper) was mounted upon each side of the inkin* apparatus, the form being made to traverse under both of them. This double-action ma' chine threw ofi" 1100 impressions per hour when first finished; and by a subsequent im- provement, no less than 1800. Mr. Konig's next feat was the construction of a machine for printing both sides of 1175 Konig's double, for both sides of the sheet. the newspaper at each complete tra- verse of the forms. This resembled two single machines, placed with their cylinders towards each other, at a dis- tance of two or three feet; the sheet was conveyed from one paper cylinder to another, as before, by means of tapes ; the track of the sheet exactly resembled the letter S laid horizontally, thus, co; and the sheet was turned over or reversed in the course of its passa-e. At the first paper cylinder it received the impression from the first form, and at the second it re- ceived It from the second form; whereby the machine could print 750 sheets of book letler-press on both sides m an hour. This new register apparatus was erected for Mr. r r'.\" ^^^r^""^ ^^^h ^^'""^ *^^ ''"^y machine made by Mr. Kunig for printing npon both sides. See^g. 1175. = r s Messrs. Donkin and Bacon had for some years previous to this date been busily engaged with printing machines, and had indeed, in 1813, obtained a patent for an 11^® apparatus, in which the types were placed upon the sides of a re- vovmg prism ; the ink was applied by a roller, which rose and lell with the eccentricities of the prismatic surface, and the sheet was wrapped upon another prism fashioned so as to coincide with the eccentricities of the type prism. One such machine was erected for the University of Cambridge. (See ^g. 1176.) It was a Deautilul specimen of ingenious contrivance and good workman, snip. 1 hough It was found to be too complicated for common operatives and defective in the mechanism of the inking process ; «r«,i, «« T.- 1 •J^'^'^f^^^^^^'^^o^ the first time the elastic inking rollers, composed of glue combmed with treacle, which alone constitute one of the finest inventi™^^^ modern typography In Konig's machine the rollers were of metal covered w^tMeather and never answered their purpose very well i^niuer. Before proceeding further I may state thit the above elastic composition, which re- scmWes caoutchouc not a little, but is not so firm, is made by dissolving with heatTn tJ^ ^Id wa?er '^ ' °"' '"""'^ "^ ^""^ ^^"^' P^^^^^"^^^ ^^^^^^ during a nightln In the year 1815, Mr. Cowper turned his scientific and inventive mind to the subject IX-'fll^ machines, and has smce, in co-operation with his partner, Mr. Applegith carried them to an unlooked-for degree of perfection. In 1815 Mr. Cowper obtain«l a patent for curving stereotype plates, for the purpose of fixing them oS a cvliidw Pookin and Bacon's for type. M \ • f 492 PRINTING MACHINE. Several machines so mounted, capable of printing 1000 sheets per hour upon both •ides, are at work at the present day ; twelve machines on this principle having been 1177 1178 ».-♦ made for the Di- rectors of the Bank of Eng- land a short time previous to their re-issuing gold. See figs. 1177. and 1178. Cowper's single, for curred Cowper's double, for both sides of the stereotype. sheet. ^^.^, It deserves to be remarked here, that the same object seems to have occupied the attention of Nicholson, Donkin, Bacon, and Cowper ; viz., the revolution of the form of type3. Nicholson sought to effect this by giving to the shank of a type a shape like the stone of an arch; Donkin and Bacon by attaching types to the sides of a revolving pnsm; and Cowper, more successfully, by curving a stereotype plate. (See /^. 1177.) In these machines Mr. Cowper places two paper cylinders side by side, and against each of them a cylinder for holding the plates ; each of these four cylinders is about two feet in diameter. Upon the surface of the stereotype-plate cylinder, four or five inking rollers of about three inches in diameter are placed ; they are kept in their position by a frame at each end of the said cylinder, and the axles of the rolitr*! rest in vertical slots of the frame, whereby, having perfect freedom of motion, they act by their gravity alone, and require no adjustment. The frame which supports the inking rollers, called the wavmg-frame, k attached by hinges to the general framework of the machine; the edge of the stereotype-plate cylin- der is indented, and rubs against the waving-frame, causing it to vibrate to and fro, and consequently to carry the inking rollers with it, so as to give them an unceasing traverse movement. These rollers distribute the ink over three fourths of the surface of the cylinder, the other quarter being occupied by the curved stereotype plates. The ink is contained in a trough, which stands parallel to the said cylinder, and is formed by a metal roller revolving against the edge of a plate of iron ; in its revolution it gets covered with a thin film of ink, which is conveyed to the plate cylinder by a distributing roller vibrating between both. The ink is diffused upon the plate cylinder as before described ; the plates in passing under the inking rollers become charged with the colored varnish ; and as the cylinder continue? to revolve, the plates come into contact with a sheet of paper on the first paper cylinder, which is then carried by means of tapes to the second paper cylinder, where it receives an impression upon its opposite side from the plates upon the second cylinder. Thus the printing of the sheet is completed. Though the above machine be applicable only to stereotype plates, it has been of general importance, because it formed the foun- dation of the future success of Messrs. Cowper and Applegalh's printing machinery, by showing them the best method of serving out, distributing, and applying the colored varnish to the types. In order to adapt this method of inking to a flat type-form machine, it was merely requisite to do the same thing upon an extended flat surface or table, which had been performed upon an extended cylindrical surface. Accordingly, Messrs. Cowper and Applegath constructed a machine for printing both sides of the sheets from type including the inking apparatus, and the mode of conveying the sheet from the one paper cylinder to the other, by means of drums and tapes. It is highly creditable to the scien- tific judgment of these patentees, that in new modelling the printing machine they dis- pensed with forty wheels, which existed in Mr. Konig's apparatus, when Mr. Bensley re- quested them to apply their improvements to it The distinctive advantages of these machines, and which have not hitherto been equalled, are the uniform distribution of the ink, the equality as well as delicacy with which it is laid upon the types, the diminution in its expenditure, amounting to 1^ J 1179 one half upon a given quantity of letter-press, and the facility with ^ it which the whole mechanism is managed. The band inking-roller and distributing-table, now so common in every printing-office in Eu- rope and America, is the invention of Mr. Cowper, and was specified in his patent. The vast superiority of the inking apparatus in his ma- chines, over the balls used of old, induced him' to apply it forthwith to the common press, and most successfully for the public ; but with little or no profit to the inventor, as the plan was unceremoniously in- fringed throughout the kingdom, by such a multitude of printers, whether rich or poor, as to render all attempts at reclaiming his rights by prose- cution hopeless. See fig. 1179. To construct a printing machine which shall throw off two sides at a time with exact register, that is, with the second side placed precisely upon the back of the 66 Cowper's inking table and roller. PRINTING MACHINE. 493 first, is a very difficult problem, which was first practically solved by Messis. Applegati and Cowper. It is comparatively easy to make a machine which shall print the one side of a sheet of paper first, and then the other side, by the removal of one form, and the introduction of another; and thus far did Mr. Konig advance. A correct register requires the sheet, after it has received its first impression from one cylinder, to travel 1180 1181 Applegath and Cowper's sing^le. Applegath and Cowper's double. round the peripheries of the cylinders and drums, at such a rate as to meet the typef of the second side at the exact point which will ensure this side falling with geome- trical nicety upon the back of the first. For this purpose, the cylinders and drums must revolve at the very same speed as the carriage underneath ; hence the least incor- rectness in the workmanship will proiW t»U« t? ^"^"^ '""""S ■•""«>•* "^ which liliewiM r.» and fall about half an Sih? the fet 2^ T^i'"^ ''^"■"''" >• 2- »• ••• »■•« ™^I to and fourth The form of t™', .^pls'n- fro^f .""""''''''•"''""^'y' ■" »'«' ""e ^nd returning from b to a, it prints shee?r»tf.„^^ I',' P"°'» sheets at I and 8 • in to give the imnreesion. anTriles to ^rmit ??e f^^ J?"" ""' ^^^'"^'' «lton,atel/felS Zt\ 'J'?KP""J'''e cvlitlder, and^S uptarda to ; '^ '^^ '»P*' '• ^ parted, and the sheet falls into the bands S »K?» j fv"' "■ »■ ^"""e tbe tapes »• 18 so perfectly equipped, that h^^.r^'i^tl^Tt'^J^^""'^^'"^^'^^ the form « brought into the machine^ZS The "^Jd ^f v'"?'" '"" ■"'■"■t'' «f^ last few years, ^C^Z rmenrStm wlJ'* T^."' «>« ^''- "-tU the dered it necessary to provide a mXe wui "X"* ^T^^ "P"- "» powers rei the paper per hour. '' "™"'° """<* """W "or* off at Ua.t 10,000 co^^ whaf r^tef^aTru^dltC^ r ""'■^ •' » "----y ^ observe that one by one t^ the fingerWf The Machine bv.„P?r''^'" '«P™'*d must iTdel?™^ machine, they are carried through "irktedhf" V ^•'*" ^^^ "^ *° « tU the case of sheets so laree as th th?fet aDoeal (26 X 2 + 4Crx2) , the sin, bTinf iJr !' ! L ^cyande of potassiui, 132,= The crystUs of prusViate „fZ«h Ll Slarl r™ ""'"^ 10 in the seale of equivalent, somewhat bitterish tastVXbte in 4 „ZV ".'"'"""J'if ''"' "'^ « sweetish saliue and water, but insoluble in alcS TV. Tt 1 ""'"■ ?' *^ *"•' """l '" ' !»« of boil'ne l«!ni"t? "^""^'^ ''«™ °to.eIS:r,h.rrt":'lL'"^^^^^^ ""' <"dinar;terapera.:re,! losing their form or cohprpni.*. o«^ v ^ , "" ^^* P^"" cent, of water witimnt PRUSSIAN BLUE. 501 Metallic solutions. Antimony - . . Bismum Cadmiam - _ . Cerium (protoxyde") Cobalt - . Copper (protoxyde) - Do. (peroxyde) Iron (protoxyde) Do. (peroxyde) Lead Manganese (protoxyde) Manganese (deutoxyde) Mercury (protoxyde) - Do (peroxyde) * Molybdenum Nickel (oxyde) Palladium (protoxyde) Silver - . , Tantalum Tin (protoxyde) Do. (peroxyde) Uranium Zinc - . - white. C«Jo''ofP"«Pitate. - white. - white, a Ht.Ie yellowish. - white, soluble in acids. - green, soon turning reddish-gray. - white, changing to red. - brown-red. - "^hite, rapidly turning blue. - dark blue. ^ - white, with a yellowish cast. - white, turning quickly peach or blood-red. - greemsh-gray. - white. - white, turning blue. - dark brown. - white, turning greenish. - green (gelatinous.) - white, turning brown in the light. - yellow, dark burned color. - white, (gelatinous.) - yeJlow, do. - red-brown. - - white. yttri:,^;3t^^^^^^^ or earthy salts, except that of t^e metal thrown lw„rw\"l^ f^'^^.^S^^^^^ with'cy'Sfo? cyanide of potassium and the Deeuli«r^roi?- ^i^ reciprocal decomposition of the cipitate from the sulphate of ^op^Y Tas a fine'Zn' ^''^l'^" '" 'J»^ ^«^"^^"- The pre! pigment; but it is somewhat tSlrent !n^fi,T" T^«'> *«d has been used as a cipitate from the peroxvde s-ltf ^/" ? ^ therefore does r.ot cover well. The Dre continent, Paris bire:X:fbrr2r^^^^^ P^"^-" blue, call J'^the prussiate of peroxyde of iron ; or as'a d^bu ? ^^^P^^jd of prussiate of protoxyde and iron, as the denomination ^JnZfe^r^TfI^:Z''i^^ ^^ the protoxyde and peroxyde of may be therefore stated thus^ pms^^r^vH^^^- *^^"?i^'- ^" '^"mbers, its composition peroxyde of iron, 30-79; or c^yTnogen ifi??^^^ protoxyde of iron, 20-73" sent its constitution when it isforS'bv Zj- T.^ ^^'^^V^^^^^^ ^^'^^ ; which reprel sa t of iron that contains no prSyde ^ Tf th? • ^"*' k V^ '^' ^'""'^^^'^ ^^ P^^ash or a Wit, it will afford a precipitate, at/m'pa e uV'Z^l ?"' ^^'/'^^^^ peroxydized in the swting of a mixture of prussiate of Tro?oxvde aJ '^ ' • ?' ^r"^ ""^ ^ '^^ ^'''> <^«^ white cyanide of iron (the prussiate of the pure ^inJfT\^^ ^^'^^^'de. In fact, the V y ic oi me pure protoxyde), when exposed to the air in a moist condition, becomes, as above stated, dark blue; yet the new combination formed in this case through absorption of oxygen, is essentially different from that resulting from the precipitation by the peroxyde of iron, since it contains an excess of the peroxyde in addition to the usual two cyanides of iron. It has been therefore caUed basic Prussian Wiw, and, from its dissolving in pure water, solitble Prussian blue. Both kinds of Prussian blue agree in being void of taste and smell, in attracting humidity from thj air when they are artificially dried, and being decomposed at a heat above d48 F. The neutral or insoluble Prussian blue is not affected by alcohol; the basic, when dissolved in water, is not precipitated by that liquid. Neither is acted upon by dilute acids ; but they form with concentrated sulphuric acid a white pasty mass. From which they are again reproduced by the action of cold water. They are decom- posed by strong sulphuric acid at a boiling heat, and by strong nitric acid at common temperatures ; but they are hardly affected by the muriatic. They become green with chlorine, but resume their blue color when treated with disoxydizing reagents. When Prussian blue is digested in warm water along with potash, soda, or lime, peroxyde of iron IS separated, and a ferroprussiate of potash, soda, or lime remains in solution. II the Prussian blue has been previously purified by boiling in dilute muriatic acid, and washing with water, it will afford by this treatment a solution of ferrocyanodide of po- tassium, from which by evaporation this salt may be obtained in its purest crystalline state. When the powdered Prussian blue is diffused in boiling water, and digested with red oxyde of mercury, it parts with all its oxyde of iron, and forms a solution of bi-cy- anodide, improperiy called prussiate of mercury ; consisting of 79-33 mercury, and 20-67 cyanogen; or, upon the hydrogen equivalent scale, of 200 mercury, and 52=(26X2) cyanogen. When this salt is gently ignited, it affords gaseous cyanogen. Hydrocyanic or prussic acid, which consists of 1 atom of cyanogen = 26, -f 1 of hydrosen = 1, is prepared by distilling the mercurial bi-cyanide in a glass retort with the satutjiting quan- tity of dilute muriatic acid. Prussic acid may also be obtained by precipitating the mer- cury by sulphureted hydrogen gas from the solution of its cyanide; as also by distilling the ferrocyanide oi potassium along with dilute sulphuric acid. Prussic acid is a very ▼olatile light fluid, eminently poisonous, and is spontaneously decomposed by keeping, es- pecially when somewhat concentrated. Haying expounded the chemical constitution of Prussian blue and prussiate of potash. I shall now treat of their manufacture upon the commercial scale. l.Ofblood-ley, the phlogisticated alkali of Scheele. Among the animal substances nsed for the preparation of this lixivium, blood deserves the preference, where it can be had cheap enough. It must be evaporated to perfect dryness reduced to powder and sifted Hoofs, parings of horns, hides, old woollen rags, and other animal offals, are, however^ generally had recourse to, as condensing most azotized matter in the smaUest bulk. Dried funguses have been also prescribed. These animal matters may either be first carbonized m cast iron cylinders, as for the manufacture of sal ammoniac (which see), and the residual charcoal may be then taken for making the ferroprussiate ; or the dry animal matters may be directly employed. The latter process is apt to be exceedingly offensive to the work- men and neighborhood, from the nauseous vapors that are exhaled in it. Eight pounds of horn (hoofs), or ten pounds of dry blood, afford upon an average one pound of charcoal. This must be mixed well with good peariash, (freed previously from most of the sulphate of potassa, with which it is always contaminated), either in the dry way, or by soakin* the bruised charcoal with a strong solution of the alkali ; the proportion being one pari of carbonate of potassa to from 1^ to 2 parts of charcoal, or to about eight parts of hani animal matter. Gautier has proposed to calcine three parts of dry blood with one of ni tre ; with what advantage to the manufacturer, I cannot discover. The pot for calcining the mixture of animal and alkaline matter is egg-shaped as represented at a, yig. 1188 and is considerably narrowed at the neck «, to facilitate th^ closing of the mouth with a lid i. Ii Ls made of cast iron, about two inches thick in the belly and bottom; this strength being requi- site because the chemical action of the ma- terials wears the metal fast away. It shouki be built into the furnace in a direction sloping downwards, (more than is shown in the figure), and have a strong knob b, projecting from its bottom to support it upon the back wall, while its shoulder is embraced at the arms c, c, by the brickwork in front. The interior of the furnace is so formed as to leave but a space of a few inches round the pot, in order to make the flame play closely over its whole surface. The fire-door/, and the draught- hole Zf of the ash-pit, are placed in the pos- — terior part of the furnace, in order that the workmen may not be incommoded by the heat. The smoke vent o, issues through the 502 PRUSSIAN BLUE. a !•• . .^;! ,^» u "* "^ I'^'^civeu. Ai mis time, the neat should be increased thp mm.fj, «r «k« In^ '^^^^^aaiiy Kept up, the flame becomes less and less each time that the not w on^nli with iron-rust cement, and re-inserted with thpcnnn^ a \,^ ^umace, patched up solution was emploved direotlv fnr tKo «,.o«:,.;t„«- r ^"""^"y/nai very complex impure regulated works, i^rcoTvertVbv evln^^^^^^ of Prussian blue ; but now, in all well of potash. The mother watPrJ«LJ-^ f "? ^°5^'"" '"*° crystallized ferroprussiate inferior ferroprusSate isTbtainid ^=^'" f^^''^'''^ .^"^ crystallized, whereby a somewhat add as much solu on of er"iohrte of^rL'^r/^^ '''i '^' ^'^7^^' '' '^ ^^^^^^^e to tate of cyanide of iron wh'T first fak I idth i ^' ""'" re-d,ssolve the white precipi- which is present in thJl oL fntn f^ f ^^/ *'°''^^.'' ^^^ ^>'*"^^« ^^ potassium, siate of potash may be rendered ciemtT/'"^^' k^ potassium. The commercial prus-' stove, fusing them whh a Ini h-t ^ ^^^'^ ^ " -^ '^' "^'^*^' effloresce in a neutralizin/anyca7Cate^anfcvaniL'%*^.^^l%l''°'''*^'^^^^^^^ '^' "^^'^ ^^ ^«ter, then precipitating the fer oprussia^te o^ r^2? i^?^ ^' S"""'""* ^^^^ «^^»'^ «^iJ alcohol, and finally cryslEn' he nreS^-' ^'* ''' * '"^"'"' ^"'"'^''^ "^ of potassa may be dewmposed bv aopt«?p nf k f ^^ ^wice over in water. The sulphate removed by alcohol. ^ ^ ^''^^^^ *^^ ^^-"y^^' ^"^ ^^^ ''^s^lti"? acetate of potassa ^yle'^^tnZ:^::!^^^^^ -;P»;^te of iron is always employed prussiate, in forming Prussian blue thouah^thP r' ^ f^u '"" "^-'^^ '°^"^^°" «^ ^^^^ ^^"'>' would afford a much richer bhiep^Jment'V^^^ ""''T' ^ '""T^t «^ -oa carefuUy freed from any cupreoL^ i^P-gn^^' T^^ PRUSSIAN BLUE. 503 dirty brownish cast. The green sulphate of iron is the most advantageous precipitant, on account of its affording protoxyde, to convert into ferrocyanide any cyanide of po- Ussium that may happen to be present in the uncryslallized lixivium. The carbonate of potash in that lixivium might be saturated with sulphuric acid before adding the solution of sulphate of iron; but it is more commonly done by adding a certain portion of alum; in which case, alumina falls along with the Prussian blue; and though it renders it somewhat paler, yet it proportionally increases its weight ; whilst the acid of the alum saturates the carbonate of potash, and prevents its throwing down iron-oxyde, to degrade by its brown-red tint the tone of the blue. For every pound of pearlash used in the calcination, from two to three pounds of alum are employed in the precipi- tation. When a rich blue is wished for, the free alkali in the Prussian ley may be partly saturated with sulphuric acid, before adding the mingled solutions of copperas and alum. One part of the sulphate of iron is generally allowed for 15 or 20 parts of dried blood, and 2 or 3 of horn-shavings or hoofs. But the proportion will depend very much upon the manipulations, which, if skilfully conducted, will produce more of the cyanides of iron, and require more copperas to neutralize them. The mixed solutions of alum and copperas should be progressively added to the ley as long as they produce any precipitate. This is not at first a fine blue, but a greenish gray, in consequence of the admixture of some white cyanide of iron ; it becomes gradually blue by the absorption of oxygen from the air, which is favored by agitation of the liquor. Whenever the color seems to be as beautiful as it is likely to become, the liquor is to be run off by a spigot or cock from the bottom of the precipitation vats, into flat cisterns, to settle. The clear supernatant fluid, which is chiefly a solution of sulphate of potash, is then drawn off by a syphon ; more water is run on with agitation to wash it, which after settling is again drawn off; and whenever the washings become tasteless, the sediment is thrown apon filter sieves, and exposed to dry, first in the air of a stove, but finally upon slabs of chalk or Paris plaster. But for several purposes, Prussian blue may be best employed in the fresh pasty state, as it then spreads more evenly over paper and other surfaces. A ffood article is known by the following tests : it feels light in the hand, adheres to the tonffue, has a dark lively blue color, and gives a smooth deep trace; it should not effervesce with acids, as when adulterated with chalk ; nor become pasty with boiling water, as when adulterated with starch. The Paris blue, prepared without alum, with a peroxyde salt of iron, displays, when rubbed, a copper-red lustre, like indigo. Prus- sian blue, detfraded in its color by an admixture of free oxyde of iron, may be im- proved by digestion in dilute sulphuric or muriatic acid, washing, and drying. Its rela- tive richness in the real ferroprussiate of iron may be estimated by the quantity of potash oi soda which a given quantity of it requires to destroy its blue color. Sulphureted hydrogen passed through Prussian blue diffused in water, whitens it; while prussic acid is eliminated, sulphur is thrown down, and the sesquicyanide of iron is converted into the single cyanide. Iron and tin operate in the same way. When Prussian blue is made with two atoms of ferrocyanide of potassium, instead of one, it be- comes soluble in water. For the mode of applying this pigment in dyeing, see Cauco-printing. Sesqui/errocyanate of potash is prepared by passing chlorine gas through a solution d ferrocyanide of potassium, till it becomes red, and ceases to precipitate the peroxyde salts trfiron. The liquor yields, by evaporation, prismatic crystals, of a ruby-red transparency. They are soluble in 38 parts of water, and consist of 40*42 parts of sesquicyanide of iron, and 59'58 of cyanide of potassium. The solution of this salt precipitates the foUowisg metals, as stated in the tablt? ; — Bismuth Cadmium Cobalt Copper (protox3'de) Do. (peroxyde) Iron, protoxyde salts of blue. Manganese - - brown. Mercury (protox^'de) red-brown. Neto process for prussian blue, which deserves peculiar notice, as the first in which thif interesting compound has been made to any extent independently of animal matter. Mr. Lewis Thompson received a well-merited medal from the Society of Arts, in 1837, for this invention. He justly observed that in the common way of manufacturing prussiate of potash, the quantity of nitrogen furnished by a given weight of animal matter is not large, and seldom exceeds 8 per cent. ; and of this small quantity, at leaal one half appears to be dissipated during the ignition. It occurred to him that the atmosphere might be economically made to supply the requisite nitrogen, if caused to Act in favourable circumstances upon a mixture of carbon and potash. He found tb« pale yellow. yellow. dark brown-red. red-brown. yellow-green. Mercury (peroxyde) Molybdenum Nickel Silver Tin (protoxyde) Uranium - Zinc yellow. red-brown. yellow-green. red-brown« white. red-brown. orange-yellow. 504 PRUSSIATE OF POTASH. 1 i: I P 3 ,1' $ foUowing prescription to answer. Take of pearlash and coke each 2 nartg • iron turnings, 1 part; grind them together into a coarse powder plL^ this m an onen crucible, and expose the whole for half an hour to a fSl r.d hW^tlTan opei^ Z Zth occasional stirring of the mixture. During this process, little iet« of puX flame will be observed to rise from the surface of the materials. When these ceShecrucrble must be removed and allowed to cool. The mass is to be lixivfated \lie iSv^ which IS a solution of ferrocyanide of potassium, with excess of potash is to be TreltS m the usual way, and the black matter set aside for a fresh operation ^^th a fresh dose of peariash Mr Thompson states that one pound of peariasrcJ^taininr45 Tabont f *^^"^'' ^''^f^ '^'' e^*^^« «^ P^^^ ^^"««i^^ Wue,^or ferr Van^d',";"\>of . or about 3 ounces avoirdupois. j""iuc ui iiou , PRU^IATE OF POTASH. Leuch's Polytechnic Zeitnng, June, 1837. Manufac tare of Kalium Eisen Cyanure, by Hofflmayr and Prukner.-The potash musfbeire^ from sulphate, for each atom of sulphur destroys an atom of the Eisencyankalium A very s rong heat is advantageous. The addition of from 1 to 3 § of saltpetre is useful when the mass is too long of fusing. A reverberatory furnace (flammofen) is recom-' ^o? r ' .u"* ^.,?u^"^ "''''^ ''^^ ^^^ ^"^ '""^^^ "Pon ^^^ materials, for fear of oxy- genating them. When the smoky red flame ceases, it is useful to throw in from time to t me small portions of uncarbonized animal matter, particularly where the flame first beats upon the mass, whereby the resulting gases prevent oxidation by the air. The «!T!i ?'fu"^"u'^''"^fM"^' ^ ^"^ '""'^^ carbonized, but left somewhat brown-colored, m»v i ino^^ ^ readilj' pulverized. Of uncarbonized animal matters, the proportions may be 100 parts dried blood, to from 28 to 30 of potash (carbonate), and from 2 to 4 of hammerschlag (smithy scales), or iron filings; 2, 100 parts of horns or hoofs ; from 33 Woo5 T,!f V ^ '° ^"*^? ' K^' ^^^ ^"^''^" ' ^^ '^ ^« P«*^«h 5 «»d 2 to 4 iTou. From blood, 8 to 9 per cent, of the prussiate are obtained ; from horns, 9 to 10 ; and from I if'? ''i" ^- T^^ P^*^'^ '^''''^^ ^^ °^'^^^ i^ ^««"^ particles, like peas, with th^ ^n^iu T/^u^ ""^"^V "^^r^ f ^y ^^ ^'^ ^''"^ ^° « revolving pot, containing can- ?rn^ lo t; ^^!^\*"'°^«.^ coal and potash, equal parts may be taken, except with that LnThnrn "''i "^^'VTZ^' ^ ^^^. ^^^^ °**^^ P°^««^ P^' ^^^^^ ^^ ^^^ average, blood 8° bit hv ^oi? t^""^? aff-ord never less than 20 per cent, of prussiate, nor the leather than 8; but by good treatment, they may be made to yield, the first 25, and the last from 10 Reduce charcoal into bits of the size of a walnut, soak them with a solution of car- bonate of potash in urme ; and then pour over them a solution of nitrate or acetate of m>n; dry the whole by a moderate heat, and introduce them into the cast-iron tubes presently to be described. The following proportions of constituents have been found ?^ TZ^' ''^ ^fli?"^, ^T^d^ ^^"^ ' ."''^'^' ^" ' ^*^^*"t« «^ »^«n' 15 ; <^harcoal or coke, Ur t Jhif r^ ^^T^' ^^''J^^ materials, mixed and dried, are put into retorts simi-' T^i Jin w ''?^* P-* ^^^ ^"'"".^^ ^^^^^'' ^"^^^^'^ <^^« ^lo^)> " placed in sepa- rate compartments of pipes connected with the above retorts. The pipes containing the animal matter should be brought to a red heat before any fire is placed under'' the J.^^^lV^^^^i ^» ^» ^» Is a horizontal section of a furnace constructed to receive four elliptical iron pipes. The furnace is arched in the part a, c, b, in order to reverberate the heat, and drive it back on the pipes w, w', w", w'". These pipes are placed on the plane E, r, of the ellipsoid ; a a, represents the grating or bars of the furnace to be heated with coal or coke; i, i, is the pot or retort shown in^g«. 1190, 11 yi 1192 This pot or retort is placed in a separate compartment, as seen in /Iff. 1189 which is a rretrr Cm^^^^^^^^^^^^ T" '' ^'^ ^-^ - ^^ - « — ^-^ tube, from In section. Jig. 1190., the shape of the tube k will be better seen ; also its cocks «. ajad likewise Its connection with the pipes w. I, is a safety valve ; «, the cover of the pot or retort ; i, is the ash-pit ; and 6, the door of the furnace ; x, is an open ST'^tler'' ''''''''' '*'" * ^'^ ^^^^ *'^''^® ^"^ ^^^ furnace, and under it the pipes are The arrows indicate the direction of the current of heat This current traverses the intervals left between the pipes, and ascends behind them, passing through the aperture J, m the brick work, which is provided with a valve or 4mper, for cloliiiij it, AS reqmred. The heat passes through this aperture, and strikes against the sides of the pot when the valve is open. Another valve /. g, must also be open to expose the mto^a chimne n *''^''''' ""^ ^^ ^^* ^^^ '"'''^^ ^^^^^ ^^ * lateral passage It must be remarked that there is a direct communication between the chimney and that compartment of the furnace which contains the pipes, so that the heat, reflected from the part v, strikes on the pot or retort only when the pipes w, w', w". w'". are •omciently heated. *^ , , , , »ic in Jig. 1191. is shown an inclined plane m (also represented in;?^. 1190.) and the juno- PRUSSIATE OF POTASH. 505 1189 1191 tion-tubes which connect the four pipes with their gas-burners z, z, and the cocks m, m'. r, r, are covers, closing the pipes, and having holes formed in them ; these holes are shut by the stoppers e. Whether the pipes are placed in the vertical or horizontal position, it is alwa^'s proper to be able to change the direction of the current of gas ; this is easily done by closing, during one hour (if the operation is to last two hours,) the cocks i, m' and opening those u', m ; then the gas passes through %i\ into the branch k, and entering w , passes through q, into w", through jt>, into w', and through o, and w, and finally escapes by the burner z. During the following or other hour, the cocks u' in, must be closed : the cocks u, m', being opened, the current then goes from u, into k w w' w", w'", and escapes by the burner z', where it may be ignited. ' ' * The changing of the direction of the current dispenses, to a certain degree with the labour required for stirring with a spatula the matters contained in the pipes • never- theless, It IS necessary, from time to time, to pass an iron rod or poker amongst the substances contamed in the pipes. It is for this purpose that apertures are tormed. so as to be easily opened and closed. The patentee remarks, that although this operation is only described with reference to potash, lor obtaining prussiate of potash, it is evident that the same process is applicable to soda: and when the above-mentioned ingredients are employed soda being substituted for potash, the result will be prussiate of Boda.— Newton s Journal C. S. XXI. 96. ' Manv/actiirc of Prussiate of Potash. All things considered, the manufacture of prussiate of potash is, perhaps, less understood, and therefore less perfect, than that of any other chemical substance of equal importance. The conditions requisite to ensure success are totally unknown amongst scientific men, and the manufacturers themselves seem so divided m their opinions respecting the best modes of production, that nothing valuable can be deduced tiom the discordant results of their experience. Thus, whilst some are so careful to avoid the presence of water in the materials they employ that these are highly dried before being cast into the furnace pot, others pay no regard at all Vol. IL 2 T i«M ^^^ •fc»> 506 PRUSSIATE OF POTASH. PRUSSIATE OF POTASH. 607 to this circumstance, or even actually wet the nitrogenised substances, with a view to increase their power. The diflference in theory between these methods is so enormous, that it ought, long ago, to have shown itself in the practical results, if there be not some error in the assertion that prussiate of potash is entirely destroyed by steam at a red heat That such is the case when pure prussiate is thus acted on, no one can doubt for a moment ; but how far this is true with respect to the mixture of carbonaceous and alkaline matters contained in the furnace pot of a prussiate manufacturer, remains still to be investigated. Whatever be the plan adopted, a prodigious waste invariably occurs in making prussiate of potash ; and fully two-thirds of all the nitrogen, exist- ing in the azotised ingredients of the process, are driven off and lost More frequently, indeed, the loss amounts to three-fourths, and even this is sometimes exceeded. The state of the weather, and the temperature of the furnace, also largely affect the production of prussiate of potash, — for damp, foggy weather, and a low, dull heat, are extremely prejudicial. The most favourable indications are, a heat verging on whiteness, and th« production of a clear, bright flame, the moment the materials are thrown into the pot Woollen rags or clippings, and good American potash or pearlash, with an admixture of scrap iron, have given a larger produce than any other substances within the range of our experience, though, even in this instance, two-thirds of the whole nitrogen passed away as ammonia. In general, 1 ton of dried blood, or woollen rags, with about 3 cwts, of good potash, will produce from 2 cwts. to 2^ cwts. of prussiate of potash, and a pro- portionate amount of sulphate of potash. The presence of scrap iron in a proper state of subdivision is, however, necessary to insure the above result ; for when no more is supplied than that which arises accidentally from the iron pot in which the operation is carried on, scarcely half these proportions will be obtained. A very useful mixture may be made of 1 ton of proper nitrogenised matter in a dry condition, with from 3 to 4 cwts. of pearlash in powder, and 50 or 60 lbs. of scrap iron in the form of wire, or thin sheets or clippings. This is to be projected by degrees into a thick iron pot previously brought to a bright cherry-red heat ; and, after each addition, the whole contents of the pot must be well stirred with a heavy iron poker or bar, until the residue becomes pasty ; when more of the mixture must be thrown in and similarly treated, until the pot is about half full; after this, the heat may be maintained for 15 or 20 minutes; and then the charge must be ladled out to make room for another operation. The form and nature of the iron pot are by no means matters of indiflFerence. The form should be such as to prevent the access of air as much as possible, without causing unnecessary labour to the workmen in the charging and emptying of the pot ; and, in consequence of the high temperature employed, the cast-iron should be of the kind called " cold-blast iron ; " for this will resist a much greater application of fire than " hot-blast iron." The old shape of a prussiate of potash pot is almost exactly that of an egg, with its upper part cut off ; and this, in an economical point of view, is scarcely susceptible of improvement ; but the pasty mass, after each operation, can be removed from this pot with great difficulty only ; and the mixing or stirnng is still more open to objection. Nevertheless, many manu- facturers continue to employ this form. More recently, a kind of oblong shallow trough has come into use, which presents every facility for charging and discharging ; but the waste of nitrogen is said to be considerable, and the wear and tear excessive ; so that a middle shape, or combination of the two, appears indicated. We have, however, witnessed the employment of common gas-retorts for this purpose, and with the most unqualified success. In these, the action of the air is entirely prevented, and the stirring process goes on through an opening in the cover, which, being provided with a plug or stopper, permits the occasional condensation of much of the waste ammonia to take place ; or, by the use of what are called " reciprocating retorts," enables the manufac- turer to pass the volatile matters, arising from a recent charge, over the incandescent ma- terials of an old or spent charge, so as to convert the ammonia they contain into cyanogen. The fii-st steps of the operation being finished, the pasty mass is commonly allowed to cool and harden ere it is roughly powdered and boiled in water. Some manufacturers^ however, plunge it at once, whilst still red-hot, into cold water, and fancy that some advantage is thus gained. In a theoretical view, the proper course would be to cover up the red-hot mass, so as to obstruct both the access of air and moisture, and thus prevent the decomposition of the cyanide of potassium during the process of cooling. As the prussiate of potash is extremely soluble in boiling water, the fused mass rapidly disintegrates beneath the action of this fluid ; and, in a short time, the whole is resolved into a solution of the prussiate, carbonate, and sulphate of potash, and into an insoluble magma of carbon and scrap-iron. By filtration, the saline fluid is sepa- rated from the insoluble portion ; and, after evaporation, furnishes crystals of prussiate of potash, mixed with sulphate of potash, which, by re-solution and crystallization, are rendered sufl&ciently pure for the market Some years ago, the Society of Arts presented their gold medal to Mr. L. Thompson, for his discovery of the manufacture of prussiate of potash by means of the nitrogen of the air; and several patents have since been taken out for improvements in the apparatus needed to render this discovery available. The process is at present conducted on a large scale at Newcastle-upon-Tyne, and seems to answer the object contemplated We have not,however,had an opportunity of becoming acquainted with its commercial advantages, though, on sanitary grounds, these are of the highest importance. The fact that atmospheric nitrogen can be brought into chemical union is, nevertheless, thoroughly established by this discovery, — which should therefore stimulate inventors to further efforts for utilising this great storehouse of azote. If nitrogen can be made to unite with carbon, why should it not also be made to combine with hydrogen, and thus pro- duce ammonia ? Twenty years ago the one of these combinations was seemingly as improbable as the other. Much attention has of late been drawn to the cyanogen compounds evolved during the distillation of coal in the manufacture of gas ; and it must be confessed that a wide field for improvement is opened in this direction. The quantity of cyanogen triven off during the decomposition of one ton of common Newcastle coal is sufficient to'producc about 7 pounds of Prussian blue, which, at the existing market-price, would greatly exceed the total value of the coal. The cyanogen is most probably evolved in the fonn of C3'anide of ammonium, and therefore requires protoxide of iron for the purpose of rendering it a fixed and permanent salt. Hence, if either the protoxide or peroxide of iron be placed, so that the gaseous constituents of the coal are made to pass through or over these oxides, a quantity of Prussian blue, and prussiate of ammonia, are generated . and this process may be repeated until almost the whole of the oxide of iron has been converted into ferrocyanic acid and Prussian blue. We have said, that the peroxide of iron will answer this end as well as the protoxide ; but, in reality, it is still the protoxide which acts, for the impure coal-gas always contains sulphuretted hydrogen ; and this, as is well known, has the property of reducing the peroxide of iron to the protoxide ; consequently, both are equally efficacious in the production of ferrocyanic acid. When impure coal-gas, therefore, has been passed, for some time, over either of the oxides of iron, a substance results, from which prussiate of potash may be obtained, at a rate which must, one day, lead to the total suppression of the present mode of making that article. Let us suppose, for example, that a few pounds of oxide of iron have been mingled with sawdust, and subjected to the action of the impure gas arising from the distillation of 50 tons of coal : then sufficient cyanogen must have combined Avith the iron to generate 35 pounds of Prussian blue, and this too without the least expense. Now these 35 pounds of Prussian blue, when treated with caustic lime and sulphate of potash, would afford oxide of iron, sulphate of lime, and prussiate of potash, by double decomposition, — the latter of which would require only to be crystallized from the fluid in which it was dissolved; whilst the sulphate of lime and oxide of iron might be returned again to the position formerly occupied by the oxide of iron alone, and there made to combine with a fresh portion of cyanogen ; and so on, time after time. We have seen some cwts. of prussiate of potash prepared in this way by Mr. Laming, of the Chemical Works, Millwall, and can answer for the purity and value of the article. Mr. Laming has also manufactured, in a similar manner, several beautiful samples of Prussian blue. There is, however, an art connected with the production of Prussian blue, which requires more than mere purity of materials ; for if an inexperienced individual were to attempt to make a good marketable Prussian blue, even though possessed of the purest re-agents, he would certainly fail to bestow upon it the essentml conditions of colour and cohesion, by which alone it attains a commercial value. The old mode of obtaining this article, in a proper state, was by precipitating a solution of common copperas, or protosulphate of iron, by a mixed solution of the carbonate and ferrocyanate of potash, and allowing the mixed precipitate of oxide and prussiate of iron to remain, for three weeks, in contact with the air ; when it was, in technical language, " brightened" by the addition of a dilute acid, generally muriatic. The theory of this process appears to have been this — in the first place, protocyanide and protocarbonate of iron were precipitated together, and these, by exposure to the air, passed into the state of peroxide of iron and Prussian blue ; the peroxide of iron meanwhile acting mechanically, and preventing the particles of Prussian blue from cohering together and becoming one hard mass, as invariably happens when no such impediment to cohesion is present Having attained this end, the dilute muriatic acid was employed to dissolve away the superfluous oxide of iron, and thus bring out the brilliancy of the blue colour, whilst it increased the peculiar spongy and friable nature of the product, and this, after copious ablutions of hot water, was next dried on a stone and sent to market The practice of the present day is, however, much simpler and speedier than this ; for, instead of 3 weeks, scarcely 3 days are now necessary for the production of Prussian blue. The plan generally followed is, to dissolve, in two separate portions of boiling water, exactly as much protosulphate of iron and prussiate of potash as will mutually decom pose each other ; and, for this purpose, nothing but actual experiment must be depended on, as the atomic numbers of these substances do not give a good result Assuming, 8T2 508 PRUSSIC ACID. ^rtfon nf H T ^ ^ ir?*'^T ""^ ^^ • T ^""'^ ^^ ^^«^ f«"°^ equal to a giyen ?«>- portion of tlie other and that, when mixed and thrown on a filter, neither iron nor . Ferrocyanic acid can be detected in the filtered fluid, then the mixture Ts made in the^ proportions, andaquanitv of recently precipitated peroxide of iron havingbeen added the whole IS rapidly, boilea for several minutes ; after which it is allowed U,cooL and U then brightened''' by a dilute acid, copiously washed with warm waterdried on » stove, and rendered fit for the market. Prior to drying, the colour is ^erv often brought down by the addition of inert colourless substances, such as starch! rnX^^^ ^^r^u ''1^7''''' ^^^?*' *«««rding to the object of the manufactured ^ ^ ^ ^ Ihe fabrication of what is termed the red prussiate of potash has now assumed an important position m the arts, and is supposecl by some to constitute a kbd of s^cretlS the trad^ There is, however, in truth, nothing secret about it The first method o1 forming this salt was by transmitting chlorine through a solution of ^he common prussiace of potash, until ft ceased to precipitate the permits of iron ; ^nd, as this rpTied diS^nu'^^r^ "^'^! T '^^ P*""* ^^ '^' "P^^^^«^' '^' r^«<^^«« «««»« to be regarded aXth difficult and secret: for an excess of chlorine not only constituted a waste but. mor^ ove^ actually destroyed the red prussiate when formed, and dius led to a total faTC Now however, this article is manufactured in the dry way, and the ill effects of an exce^ ofchlorine are easily obviated. To prepareita quantity of ordinary yellow pru^iateol? po ash must be reduced to a very fine powder, anil subjected to the a^^L oTcwS Lf Thurn ^^rf^V ^S^t^^r'T?"'^ ^"^^ """T^^' ^' that Aich can be produced in a TOtf^ churn. In this way the clilorme is rapidly absorbed, and chloride of potassium and red prussiate of potash generated. When it is found that the chlorine paLs freely throiSh ^e mixture, without being absorbed, the process must be stopped and the powder he^faZ\ ^^Hr^'^' ^'^ ^r ^ dissolved in the smaUest possible quantity of wlte^ heated to about 18D° Fahr., will produce, on cooling, long ne^e-shaped crystals of the red prussiate ot potash, which may be rendered purS and larger by rec^ySlli^^^^^^^^ tiie usual way; the chloride of potassium, meanwhile, reLiniig Ssolverfn the mother-hquor. It is far from improbable that this salt might be made by means of the permanganate of potash, or chameleon mineral, as the manganesic acid^parts with iU bZfi^J/'^h'''''"'''"'^'^^^^" ^^ ^"'"^^^- I^^^i« Buplosition BhouFd turnout to be correct, then a saving would occur in the process, even independently of the cost of KinnL.f?'' 7^^tu^ "^T"^ ^ '^'■'^^^ investigation by those interested inthisKancI cLiTo prin^r' '"^ ^"""""'^'^ ^ '*P^^^^ '^'^'^^e in use amongst dyers and PRUSSIC ACID; I^iebia's new test for. When some sulphuret of ammonium and caustic ammonia are added to a concentrated aqueous solution of prussie acid, and the Z^TjTi ""'-'^ '^' f 1^''^^" ^.^P^r ^^^^^ of sulphur, the prussie acid is converted in a few minutes into sulphocyanide of ammonium. This metamorphosis dependron the circumstance, that the higher sulphurets of ammonium are instantly deprived by the cyanide of ammonium of the excess of sulphur they contain above the monosulphuret for instance, if a mixture of prussie acid and ammonia be added to the pentasuiphuret wT^r^''"'! 'k' '^.^"?^'' ^^ ""^''^ '' ^^ * ^^^P >'«"«^ <^olo"r, and the whole Ctly heated, the sulphuret of ammonium is soon discolorized, and when the clear colourle^ hquid IS evaporated and the admixture of sulphuret of ammonimn expelled, a white sahni mass IS obtained, which dissolves entirely in alcohol. The solution yields orcoohng oJ evaporation colourless crystals of pure sulphocyanide of ammonium. Only a sm^ quantity of sulphuret of ammonium is requisite to convert, in presence of an excesT^ su phur, unlimited quantities of cyanide of ammonium into sulphocyanide ; because the sulphuret of ammonium when reduced to the state of monosuJphuJet, con'stantly re ac! quires its power of dissolving sulphur, and transferring it to the cy an de of amuYonii^ ll^:Z!^i:ZT:^''' "^ ^^^ 'T^ '^ ^^ advanfageous. 2 Lees of solutionTf' ^usUc ammonia, ot 0-9o specific gravity, are saturated with sulphuretted hydrogen eas • the hydrosulphuret of ammonia thus obtained is mixed with 6 ounces of the erne solution of ammonia, and to this mixture 2 ounces of the flowers of sulphur are addT and then the product resulting from the distillation of 6 ounces of prusCte of ^taslu 3 ounces of the hydrate of sulphuric acid, and 18 ounces of water. Ih s miiTure is digested m the water bath, until the sulphur is seen to be no longer altered and the hqmd has assumed a yellow colour ; it is then heated to boiling, and kept at this temi^! niture until the sulphuret of ammonium has been expelled and the liquor ImsaX become colourless. The deposit, or excess of sulphur, is now removc^d by tiltrat^ion" and the hquid evaporated to crystallization. In this way from 3] to 3i ounces are got of a dazzlmg white dry sulphocyanide of ammonium, whi/h may be employed as a reagent and for he same purposes as the sulphocyanide of potassium : of the 2 ounces of sul- phur added, half an ounce is left undissolved. The habitude of the higher sulphurets of ammonium towards prussie acid, furnishes ftn admirable test for this acid. A couple of drops of a pru.sic acid wliich has ht&i PUDDLING OF IRON. 509 dilated with so much water that it no longer gives any certain reaction with salts of iron by the formation of prussian blue, when mixed with a drop of sulphuret of ammonium, and heated on a watch glass until the mixture has become colourless, yields a liquid containing sulphocyanide of ammonium, which produces with persalts of iron a very deep blood red colour ; and with persalts of copper, in presence of sulphurous acid, white sulphocyanide of copper. PUDDLING OF IRON". This is the usual process employed in Great Britain for converting cast iron into bar or malleable iron — a crude into a more or less pure metal. The following plan of a puddling furnace has been deemed economical, espe- cially with resi ect to fuel, as two furnaces are joined side by side together, and the workmen operate at doors on the opposite sides. Fig. 1193 represents this twin furnace 119S in a side elevation; yig-. 1194in section, according to the line E F, in ^g. 1195 which exhibits a plan of the furnace. The various parts are so clearly shown in form and construction as to require no explanation. The total length outside is I4{ feet ; width, 12f feet : from which the dimensions of the other parts may be measured. Iron is puddled either from cast pigs, or from the plates of the refinery (finery) ftur- iMice. In several iron-works a mixture of these two crude metals is employed. In the refining process, the waste at the excellent establishment of Mr. Jessop, at Codner Park, is from 2^ to 2f cwt. per ton ; on which process the wages are Is. per ton ; and the coke I ton, worth 6«» ; so that the total cost of refining per ton is 15*., when pig-iron is worth 3/. 10*. The puddling is accompanied with a loss of weight of 1| cwt. per ton ; it costs In wages, for puddling refinery plates, 6s. 6d., and for pigs, 8». ; in which 18 cwt. of coal are consumed ; value, 5s. per ton. Shingling (condensing the bloom by the heavy hammer) costs, in wages, la. 9d, per ton ; and rough-rolling, Is. 2d. Cutting and weighing these bars cost 9d. for wages, including their delivery to the mill furnace, where they are reheated and welded together. The mill furnace heating costs 1«. 6d. in wages, and consumes in fuel 12 cwt of coals, at 5«. per ton. The rolling and straightening cost 6«. 6,n \^r.^ • *"*'^^™ "^gative in rela- b,a.t,f„™.ees. is subjected durC^^Lurg'':^^^^^^^^ voltaic electricity, the cliemical affinities bv whioh it* vor,'««c i.l/ poweriui stream of arc firmly associited are immediately sXU^^^ components sulphur, phosphorus, Ac, which destroy or impkiT its tena^^^^^^^^^ T' '^'^ readily separable in the act of puddling. On th 's nrincinll ^I ^"i"'^"^^^'!^*:^' t>ecome ordinary Effect of Mr. Wall's p^atent efectiST^te^^s^red i^t^^ the excellent iron-works of Mr. Jessop, at Codner Park, Derbyshire, where the elec- trised forge pigs discharge those noxious elements so copiously in the puddling fur- nace, as to become after a single re-heating, without piling or fagoting, brilliant bars of the finest fibrous metal. The bars so made have been subjected, under my inspec- tion, to the severest proofs by skilful London blacksmiths, and they have been found to bear piercing, hammering, bending, and twisting, as well as the best iron in the mar- ket I have also analysed the said iron with the utmost minuteness of chemical research, and have ascertained it to be nearly pure metal, containing neither sulphur nor phosphorus, and merely an inappreciable trace of arsenic. I can therefore con- scientiously recommend Mr. Wall's patent process to ironmasters as one of the greatest; easiest, and most economical improvements, which that important art has lately received. The pecuniary advantage of this process, in respect of saving labour and waste of material, has been estimated at one pound sterlmg per ton ; but it is not yet practically worked out. J r J The effect of electrising iron is displayed in a singular manner by the conversion into steel of a soft rod, exposed in contact with coke, for a few hours, to a moderate red heat ; a result which 1 have witnessed and can fully attest PUMICE-STONE {Pierre-ponce^ Fr. ; Bimstein, Germ.), is a spongy, vitreous-loolcing mineral, consisting of fibres of a silky lustre, interlaced with each other in all directions. It floats upon water, is harsh to the touch, having in mass a mean sp. grav. of 0*9 14 ; though brittle, it is hard enough to scratch glass and most metals. Its color is usually grayish white; but it is sometimes bluish, greenish, reddish, or brownish. It fuses without addition at the blowpipe into a white enamel. According to Klaproth, it is composed of, silica, 77-5; alumina, 17-5; oxyde of iron, 2 ; potassa and soda, 3 ; in 100 parts. The acids have hardly any action upon pumice-stone. It is used for polishing ivory, wood, marble, metals, glass, &c.; as also skins and parchment. Pumice-stone is usually reckoned to be a volcanic product, resulting, probably, from the action of fire upon obsidians. The chief localities of this minerafare the islands of Lipari, Ponza, Ischia, and Vulcano. It is also found in the neighborhood of Andernach, upon the banks of the Rhine, in TenerifTe, Iceland, Auvergne, &c. It is sometimes so spongy as to be of specific gravity 0*37. PUOZZOLANA is a volcanic gravelly product, used in making hydraulic mortar. See Cements and Mortabs. PURPLT^. OF CASSIUS, Gold purple {Pourpre de Cassius, Fr. ; Gold-jmrpnr, Germ.), is a vitrifiable pigment, which stains glass and porcelain of a beautiful red or purple hue. Its preparation has been deemed a process of such nicety, as to be liable to fail in the most experienced hands. The following observations will, I hope, place the subject upon a surer footing. The proper pigment can be obtained only by adding to a neutral muriate of gold a naixture of the protochloride and pcrchloride of tin. Everything depends upoii this intermediate state of the tin ; for the protochloride does not afford, even with a con- centrated solution of gold, either a chestnut-brown, a blue, a green, a metallic preci- pitate, or one of a purple tone ; the perchloride occasions no precipitate whatever, whether the solution of gold be strong or dilute; but a properly neutral mixture, pf 1 part of cr)'stallized protochloride of tin, with 2 parts of crystallized perchloride, pro- duces^ with I part of crystallized chloride of gold (all being in solution), a beautiful purple-colored precipitate. An excess of the protosalt of tin gives a vellow, blue, or green cast ; an excess of the persalt gives a red and violet cast ; an excess in the gold ealt occasions, with heat (but not otherwise), a change from the violet and chestnut- bro^yn precipitate into red. According to Fuchs, a solution of the sesquioxyde of tin in muriatic acid, or of the sesquichloride in water, serves the same purpose, when dropped into a very dilute solution of gold. Buisson prepares gold-purple in the following way. He dissolves, first, 1 gramme of the best tin in a sufl[icient quantity of muriatic acid, taking care that the sola tion is neutral ; next, 2 grammes of tin in aqua regia, composed of 3 parts of nitric acid, and 1 part of muriatic, so that the solution can contain no protoxyde ; lastly 7 grammes of fine gold in a mixture of 1 part of nitric acid, and 6 of muriatic, observine to make the solution neutral. This solution of a^old bein? diluted with 3| litres of water (about three quarts), the solution of the perchloride of tin is to be added at once and afterwards that of the protochloride, drop by drop, till the precipitate thereby formed acquires the wished-for tone j afler which it should be edulcorated by washing, as quickly AS pOSSlDlCa Frick gives the following prescription -.—Let tin be set to dissolve in very dilute aqua regia without heat, till the fluid becomes faintly opalescent, when the metal must be taken out, and weighed. The liquor is to be diluted laro:ely with water, and a definite weight of a dilrf^ solution of gold, and dilute sulphuric acid, is to be simultaneously stirred into the nitfo-munate of tin. The quantity of solution of gold to be poured into ^^^ PUTREFACTION. of 36 "Jo r '""'' ^' '"*^^' '^^' '^^ «^^** ^ *^« «"« i« to the tin in the other in the ratic Mu^rS^r/d^ ta^eTtre^^uf ou'f Jfl" 'l '' K ^' ^"' "P^^"^ '''^ ^' ^ dirty-brown powder. t^the seini heTl^''- /" ''' "^'''!"^ ^^^'^ ^^""^ ^^^^ ^^« ^^^^^ o^ Un accord ng of tin U.J ^-^ ^^*'^f.^s a purple oxyde along with the sesquioxyde c/ peroxvde aLoSingto!!"'"''"'^ " differenay reported by different chemist. The eons'tSts , Oberkampf, in the purple precipitate, are - . . 39^82 "^'Kg* Berzelius '''''^^^ ^^""^ .... 20-58 79-42 Buissr - 3<^-725 69-275 GayLussa I I I . I I ' ^^^ till ^ 17-87 82-13 If to a mixture of protochloride of tin, and perehloride of iron, a properlv diluted snln Uon of gold be added, a very beautiful purple precipitate of Cass us w&e^a^^^^^^^ ^P^rln r" ^'^ ^t ^^^- ^5 *^^ ""1"^^ ''' '^^ ''^^^ «^ a protochloride. The^rple thus prepared keeps in the air for a long time without alteration. Mercury doL not au! from It the smallest trace of gold.-^FuchsWmmal fur Chemiet ^y'''''^ "'^^^ "^' ^*^* nitric add ^^^t tf/?fi ' ^^ ^'/^ ''^^^'"l'^ \y ^T.*^**^ ""^ °' ^ithic acid with dilute nitnc acid. It has a fine purple color; but has hitherto been applied to no use in the «J»y7i^?^^^^^^^' """^ *'* -P*-^^'*"'^- The decomposition of animal bodies or of tTev i^e'exn^ed rih;"'" in their composition, which ^kes place sponleously ^hen facti^ V^nt ?J "' ""^^ ^^^- ^'^fl^e^ce, «f "moisture and warmth, is called putre- taction During this process, there is a complete transposition of the proximate nrin ciples, the elementary substances combining in new and principaHy gase^s iomt^unds' ofli!\y^''''^^ ^"^"^ '^^ atmosphere, and converted into carbom^add oneCuon L c^lt''^?J''"T T'' ^it\*^« o^y?en; another portion forms, wiUi Ihe^^ote" the carbon, the phosphorus, and the sulphur respectively, ammonia carburet^ phosphureted, and sulphureted hydrogen gases, which occaSonTe^au4o«s smell evolved by putrefying bodies. There remains a friable earthy-looking res duum Ton- sistmg of rotten mould and charcoal. Vegetables which contain no azote h^i the i^rS'nt'^ plants, suffer their corresponding decomposition mucrmoJe s'owly! and with diflerent modifications, but they are finally converted into vegetable mould In thLs process, the juices with which the plants are filled first enter into the acetous fer ^^ellnrnr^rh 'fi^ ""''"" of heat and moisture; the acid thereby generated destroys Se ^Pcc r t/ ^ / fi^^o"s "matter, and thus reduces the solids to a pulpy state. In the pro! ^cave ^'JlT^^'Tr' " '"j*^'""'" ''. ^^''^^ P^«^"^^^ which resembles oxyd zZ^ teacUve, IS soluble m alkalis, and is sometimes called mould. This decomposition of the plants which contain no azote, goes on without any offensive smell, as no^fof the a W nlhe'd^unTn?' nf 'Z^'^T'"'''^'- - ^^^" ^^^^^'^^^^ ^^''^^ -« -^^ wi h antat as in the dung of cattle, this decomposition proceeds more rapidly, because the animalized Ss aJe'noiTtL'iT'"' * k- '^ ^'^^^"^^J* ^^=^^^^^^ "^''^'^ '''''^'> «^ts, and voktilkS ous, are not of themselves subject to putrefaction. ^hlilf f^^""^ ^^ ^^^ ^''^''^"^ .^'""^^^ ^^ ^° ^^^^^1 ^^« principles and processes, according to rri^pn'tS' ^^"°,f P^'-P^ses in the arts, the destruction of bodies by putrefiction may b2 Rented, and their preservation in a sound state secured for a longer or a STorteJ PUTREFACTION. 511 />- I. COKDinONB OF THE PIlfiVENTION OF PTTTREFACTrOH. The circumstances by which putrefaction is counteracted, are, 1. the chemical change of the azolized juices; 2. the abstraction of the water; 3. the lowering of the tempera* ture; and 4. the exclusion of oxygen. 1. The chemical change of the azotized juices. — The substance which in dead aninoal matter is first attacked with putridity, and which ser\'es to communicate it to the solid fibrous parts, is albumen, as it exists combined with more or less water in all the animal fluids and soft parts. In those vegetables also which putrefy, it is the albumen which first suffers decomposition; and hence those plants which contain most of that proximate principle, are most apt to become putrid, and most resemble, in this respect, animal sub- stances; of which fact, mushrooms, cabbages, coleworts, &c., aflbid illusti aliens. The albumen, when dissolved in water, very readily putrefies in a moderately warm air ; but when coagulated, it seems as little liable to putridity as fibrin itself. By this change, it throws oft" the superfluous water, becomes solid, and may then be easily dried. Hence, those means which by coagulation make the albumen insjoluble, or form with it a new compound, which does not dissolve in water, but which resists putrefaction, are powerful antiseptics. Whenever the albumen is coagulated, the uncombined water may be easily evaporated away, and the residuary solid matter may be readily dried in the air, so as to be rendered unsusceptible of decomposition. In this way acids operate, which combine with the albumen, and fix it in a coagulated state, without separating it from its solution ; such is the effect of vinegar, citric acid, •arlaric aci-. &c Tannin combines with the albuminous and gelatinous parts of animals, and forms insol- uble comiwunds, which resist putrefaction ; on which fact the art of tanning is founded. Alcohol, oil of turpentine, and some other volatile oils, likewise coagulate albumen, and thereby protect it from putrescence. The most remarkable operation of this kind is exhibjled by wood vinegar, in consequence of the creosote contained in it, according to the discovery of Reichenbach. This peculiar volatile oil has so decided a power of coag- ulating albumen, that even the minute portion of it present in pyroligneous vinegar is suf- ficient to preserve animal parts from putrefaction, when they are simply soaked in it. Thus, also, flesh is cured by wood smoke. Wood tar likewise protects animal matter from change, by the creosote it contains. The ordinary pyroligneous acid sometimes coiu tains 5 per cent, of creosote. In circumstances whei-e a stronger impregnation with this antiseptic oil may be neces- saiy, common wood vinegar may be heated to 167° F., and saturated with eflloresced Glauber's saltf^, by which expedient the oil is separated and made to float upon the surface of the warm liquid; whence it should be immediately skimmed off; because, by cooling and crystallizing, the solution would so diminish in density as to allow the oil to sink to the bottom ; for its specific gravity is considerably greater than that of water. This oil, which contains, besides creosote, some other volatile constituents, may be kept dissolved ready for use in strong vinegar or alcohol. Water takes up of pure creosote only If per cent, ; but alcohol dissolves it in every proportion. The earthy and metallic salts afford likewise powerful means for separating albumen from its \vatery solution, their bases having the property of forming insoluble compounds with it. The more completely they produce this separation, the more eftectually do they counteract putrefaction. The alkaline salts also, as common salt, sal ammoniac, saltpetre and tartar, operate against putrescence, though in a smaller degree, because they do not precipitate the albumen ; but, by abstracting a part of its water, they render it less liable to become putrid. Among the earthy salts, alum is the most energetic, as it forms a sub- salt which combines with albumen ; it is three times m.ore antiseptic than common salt, and from seven to eight times more so than saltpetre. MuriatCof soda, however, may be employed along with alum, as is done in the tawing of sheepskins. The metallic salts operate still more effectually as antiseptics, because they form with albumen still more intimate combinations. Under this head we class the green and red sulphates of iron, the chloride of zinc, the acetate of lead, and corrosive sublimate ; the latter, however, from its poisonous qualities, can be employed only on special occasions. Nitrate of silver, though equally noxious to life, is so antiseptic, that a solution containing **"^^ yoo ^^ ^^^ ^*^* ^^ capable of preserving animal matters from corruption. 2. Mfiraciion of xvafer. — Even in those cases where no separation of the albumen takes place in a coagulated form, or as a solid precipitate, by the operation of a substance foreign to the animal juices, putrefaction cannot go on, any more than other kinds of fermentation, in bodies wholly or in a great measure deprived of their water. For the albumen itself runs so much more slowly into putrefaction, the less water it is dissolved in ; and in the desiccated state, it is as little susceptible of alteration as any other dry vegetable or animal matter. Hence, the proper drying of an animal substance ' ecomes a universal preventive of putrescence. In this way fruits, herbs, cabbages, fii^j, flesh. 5U PUTREFACTION. Tvln^ f 7th B , Tr I^*^«"- If ^^^ *'^ ^« »«t cold and dry enonffh to caase the evapoiation of the fluids before putrescence may come on, the organic substance must be dried by ar ificial means, as by being exposed m thin slices in properly constructed air. rir'^h^n hlT![^'"r;°'^''' T ^" '^' ."[^"."^^'^ •^"^^ "P without coagulation, .nd ^.^Lnffi.; f J ■^''r''^'^r"/*'J^. water, with its valuable properties unaltered. By such artificial desiccation, if flesh is to be preserved for cookiJig or boiling, it must not like th'rilkiir''''"'-'" '?P '"^^ ^ ^^'''f *^^"^' ""^^'^ would harden it^ermanentl? ^lll R f "1??";!"^^^ «f ^Sypt. Mere desiccation, indeed, can hardly ever be employ! ^upon flesh. Culinary salt is generally had recourse to, either alone or with the addi- tion of saltpetre or su^ar. These alkaline salts abstract water in their solution, and, consequently, concentrate the aqueous solution of the albumen; whence, by converting the simple watery fluid {hlVni Jwn/' ""au '" ^T'^^ less favorable to the fermentation of animal matter tuJ 7^'^'\""^, by expelling the air, they counteract putridity. On this account, «aUed meat may be dried in the air much more speedily and safely than fresh meat The dr^mg IS promoted by heating the meat merely to such a degree as to consolidate'the al- bumen, and eliminate the superfluous water. Alcohol operates similarly, in abstracting the water essential to the putrefaction of animal substances, taking it not only from the liquid albumen, but counteracting its de- composition, when mixed among the animal solids. Su-ar acts in the same wav, fixing in an unchangeable sirup the water which would otherwise be accessory to the feVmenta- ion of H\e organic bodies. The preserves of fruits and vegetable juices are made upon this principle. When animal substances are rubbed with charcoal powder or i^and, per- feclly dry, and are afterwards freely exposed to the air, they become deprived of their moisture, and will keep for any length of time. 3. Defect ofwarmih.-As a certain degree of heat is requisite for the vinous fermenta- tion, so IS 1 for the putrefactive. In a damp atmos,>here, or in one saturated with mois- ture, if the temperature stand at from 70° to 80° F , the putrefaction goes on most rapidlv ; but n proceeds languidly at a few degrees above freezing, and is supended altogether 'aJ that point. The elephants preserved in the polar ices are proofs of the antiseptic influ- ence of low temperature. In temperate climates, ice-houses sen-e the purpose of keeping meat fresh and sweet for any length of time. ' ^ 4. Mslradion of oxygen' gas.— As the putrefactive decomposition of a body first commences with the absorption of oxygen from the atmosphere, so it may be retarded by the exclusion of this gas. It is not, however, enough to remove the aerial oxygen from the surface of the body, but we must expel all the oxygen that may be diflused among the vessels and other solids, as this portion suffices in general to excite putrefaction if other circumstances be favorable. The expulsion is most readily accomplished by a moderate degree of heat, which, by expanding the air, evolves It in a great measure, and at the same time favors the fixation of the oxygen in the extractive matter, so as to make it no longer available towards the putrefaction of the other substances. Milk soup, solution of gelatine, &c., mav be kept long in a fre«;h state, if they be subjected m an air-tight vessel every other d'ay to a boiling heat Oxv- genation may be prevented in several ways : by burning sulphur or phosphorus in the air of the meat receiver; by filling this with compressed carbonic acid ; or with oils, fats, sirups, &c., and then sealing it hermetically. Charcoal powder recently calcined IS efficacious in preserving meat, as it not only excludes air from the bodies surrounded by It, but ntercepts the oxygen by condensing it. When butcher-meat is enclosed in a Tessel filleu with sulphurous acid, it absorbs the gas, and remains for a considerable time proof against corruption. The same result is obtained if the vessel be filled with ammo- niacal gas. At the end of 76 days such meat has still a fresh look, and may be safely dried in the atmosphere. ' ' oai^ij II. PECULIAR ANTISEPTIC PROCESSES. Upon the preceding principles and experiments depend the several processes er.'ployed for protecting substances from putrescence and corruption. Here we must distinguish between those bodies which may be preserved by any media suitable to the purpose, as •naomical preparations or objects of natural history, and those bodies which, being in- tended for food, cari be cured only by wholesome and agreeable means A common method for preserving animal substances unchanged in property and texture, is to immerse them in a spirituous liquor containing about 65 or 70 per cent of real alcohol. Camphor may also be dissolved in it, and as much common silt as its water will take up. A double fold of ox-bladder should be bound over the mouth of the vessel m order o impede the evaporation of the watery portion of the liquid, and its Tipper surface should be coated with a turpentine varnish. Undoubtedly a little creo- •ote would be of use to counteract the decomposing influence of the alcohol upon *kc PUTREFACTION. 5U . itiimal substances. With such an addition, a weaker spirit, containing no more than 30 per cent, of alcohol, would answer the purpose. Instead of alcohol, a much cheaper vehicle is water saturated with sulphurous acid; and if a few drops of creosote be added, the mixture will become very efficacious. A solution of red sulphate of iron is powerfully antiseptic ; but after some time it gives a deposite of the oxyde, which disguises the preparation in a great degree. According to Tauffier, animal substances may be preserved more permanently by a solution of one part of chloride of tin in 20 parts of water, sharpened with a little muriatic acid, than even by alcohol. For preserving animal bodies in an embalmed form, mummy-like, a solution of chloride of mercury and wood vinegar is most efficacious. As there is danger ia manipulating with that mercurial salt, and as in the present state of our knowledge of creosote we have it in our power to make a suitably strong solution of this substance in vinegar or spirit of wine, I am led to suppose that it will become the basis of most an- tiseptic preparations for the future. From the statements of Pliny, it is plain that wood vinegar was the essential means employed by the ancient Egyptians in preparing their mummies, and that the odoriferous resins were of inferior consequence. ** CURING OF PROVISIONS. Flesh.— The ordinary means employed for preserving butcher meat are, drying, smoking salting, and pickling or souring. ** Drying of animal Jihre.— The best mode of operating is as follows :— The flesh must be cut into slices from 2 to 6 ounces in weight, immersed in boiling water for 5 or 6 minutes, and then laid on open trellis-work in a drying-stove, at a temperature kept steadily about 122° F., with a constant stream of warm dry air. That the boiling water may not dissipate the soluble animal matters, very little of it should be used, just enough for the meat to be immersed by portions in succession, whereby it will speedily become a rich soup, fresh water being added only as evaporation takes place. It is advanta«'e- ous to add a little salt, and some spices, especially coriander seeds, to the water. After the parboiling of the flesh has been completed, the soup should be evaporated to a ffela- tinous consistence, in order to fit it for forming a varnish to the meat after it is dried, which may be completely eflTected within two days in the oven. By this process two thirds of the weight is lost. The perfectly dry flesh must be plunged piece by piece in the fatty gelatinous matter liquefied by a gentle heat ; then placed once more in the stove, to dry the layer of varnish. This operation may be repeated two or three times, in order to render the coat sufficiently uniform and thick. Butcher's meat dried in thS way keeps for a year, affijrds, when cooked, a dish similar to that of fresh meat and is therefore much preferable to salted provisions. The drying may be facUitated, so that larger lumps of flesh may be used, if they be imbued with some common salt immediately after the parboiling process, by stratifying them with salt, and leaving them in a proper pickling-tub for 12 hours before they are transferred to the stove. The first method however, aflfords the more agreeable article. ' 5mofeing.— This process consists in exposing meat previously salted, or merely rubbed over with salt, to wood smoke, in an apartment so distant from the fire as not to be unduly heated by it, and into which the smoke is admitted by flues at the bottom of the side walls. Here the meat combines with the empyreumatic acid of the smoke, and gets dried at the same ime The quality of the wood has an influence upon the smell and taste of the smoke-aried meat; smoke from beech wood and oak being preferable to that froni fir and larch. Smoke from the twigs and berries of juniper, from rosemary. peppermint, &c., imparts somewhat of the aromatic flavor of these plants. A slow smoking With a slender fire is preferable to a rapid and powerful one, as it allows the empyreumatic principles time to penetrate into the interior substance, without drying Si «" n^^ •°*' T.I' ^ir!"^'"' '^^.^ ^•'°'° attaching itself to the provisions, they maf Sf the op^eliron "*' *'''"' ^'^"' "^^^"^ "^^^ ^ easily removed at the end vnlTni:n'I1th''V°" v'k' ^^^^f^ "P^" *^^ ^^^'^"^ «^ ^^^ ^«o^ «cid> or the creosote volatilized with it which operates upon the flesh. The same change may be produced in a much shorter time by immersing the meat for a few hours in pyrSligneous acid, then hanging it up in a diy air, which, though moderately warm, makes it fit for keeping, rj.l^r«n7^;hrrl 'h '"'fr''- i^^^'* ^/^^ ^^^^ ^^-^P^^^"-- ^^ loses the empyreu^atfe smell, and then resembles thoroughly smoked provisions. The meat dried in this way is in general somewhat harder than by the application of smoke, and therefore softens ess when cooked, a diff-erence to be ascribed to the more sudden and concentrated opeim- tion of the wood vinegar, which effects m a few hours what would require smokinrfor several weeks. By the judicious employment of pyroligneous acid diluted to successive degrees, we migU probably succeed in imitating perfectly the eflfect of smoke in curuuf provisiCTis. ^ \r 516 PUTREFACTION. Salting.--.The meat should be rubbed well with common salt, containing about one sixteenth of saltpetre, and one thirty-secondth of sugar, till every crevice has been im- pregnated with Jt; then sprinkled over with salt, laid down for 24 or 48 hours, and, lastly, subjected to pressure. It must next be sprinkled anew with salt, packed into proper vessels, and covered with the brine obtained in the act of pressing, rendered stronger by boiling down. For household purposes it is sufficient to rub the meat well with good salt, to put It into vessels, and load it with heavy weights, in order to squeeze out as much pickle as will cover its surface. If this cannot be had, a pickle must be pour«l on It, composed of 4 pounds of salt, 1 pound of sugar, and 2 oz. of saltpetre, dis- solved in 2 gallons of water. o«» p^w , «*»- Pickling with vinegar.—YinegHT dissolves or coagulates the albumen of flesh, and there- by counteracts Us putrescence. The meat should be washed, dried, and then laid in strong vinegar. Or it may be boiled in the vinegar, allowed to cool in it, and then set aside with It in a cold cellar, where it will keep sound for several months. Fresh meat may be kept for some months in water deprived of its air. If we strew on the bottom of a vessel a mixture of iron filings and flowers of sulphur, and pour over them some water which has been boiled, so as to expel its air, meat immersed in it will ke-p fh- !;° r^ -n^ V^^^. ^ ''^''^^^'^ "^'^^ * ^*y«^ «^ oi'' ^''o°» half an inch to an inS thick. Meat will also keep fresh for a considerable period when surrounded with oil. or lat of any kind, so purified as not to turn rancid of itself, especially if the meat be fowls &J ^^^^^^^ '^ ^*"^*^ potting, and is applied successfuUy to fish, Prechtl says that living fish may be preserved 14 days without water, by stopping their mouths with crumbs of bread steeped in brandy, pouring a little brandy into them, and packing them in this torpid state in straw. When put into fresh water, they comealivc again after a few hours ! Prechtl, Encyclop. Technologisches, art. Faiilniss Mhaliung. Agg*.— These ought to be taken new laid. The essential point towards their pre- servation is the exclusion of the atmospheric oxygen, as their shells are porous, and per- init the external air to pass inwards, and to excite putrefaction in the albumen. There IS also some oxygen always in tlie air-cell of the eggs, which ought to be expelled or ren- dered inoperative, which may be done by plunging Ihem for 5 minutes in water heated to 140" h . The eggs must be then taken out, wiped dry, besmeared with some oil (not apt to turn rancid) or other unctuous matter, packed into a vessel with their narrow ends up- permost, and covered with sawdust, fine sand, or powdered charcoal. Eggs coated with gum arable, and packed in charcoal, will keep fresh for a year. Lime water, or rather mUk of lime, is an excellent vehicle for keeping eggs in, as I have verified by long expe- rience. Some persons coagulate the albumen partially, and also expel the air by boilin- the eggs for 2 minutes, and dnd the method successful. When eggs are intended fo? hatching, they should be kept in a cool cellar ; for example, in a chamber adjoining an ice-house. Eggs exposed, in the holes of perforated shelves, to a constant current of air, lose about | of a gram of their weight daUy, and become concentrated in their albuminous l)art, so as to be little liable to putrefy. For long sea voyages, the surest means of pre- serving eggs, is to dry up the albumen and yolk, by first triturating them into a homoge- neous paste, then evaporating this in an air-slove or a water-bath heated to 125°. and putting up the dried mass in vessels which may be made air-tight. When used, it should be dissolved in three parts of cold or tepid water. • i^!?'". "*[ ^" kinds, as wheat, barley, rye, &c., and their flour, may be preserved for an indefinite lengh of time, if they be kiln-dried, put up in vessels or chambers free from damp and excluded from the air. Well dried grain is not liable to the depredaUons of To preserve fruits in a fresh state, various plans are adopted. Pears, apples, plums, *c. Should be gathered in a sound state, altogether exempt from bruises, and plucked, in dry weather, before they are fully ripe. One mode of preservation is, Xo expose them in an airy place to dry a little for eight or ten days, and then to lay them in dry sawdust or cnoppeu straw, spread upon shelves in a cool apartment, so as not to touch each other. Another method consists in surrounding them with fine dry sand in a vessel which should ^Jv LT 'u'^^""^ ^^P' I" * """^^ »'**"• ^""^ Pe^'sons coat the fruit, including their stalks, with melted wax ; others lay the apples, &c., upon wicker-work shelves in a vault- ed chamber, f^^ smoke them daily during 4 or 5 days with vine branches or juniper wood. Apples thus treated, and afterwards stratified in dry sawdust, without touching each other, will keep fresh for a whole year. The drying of garden fruits in the air, or by a kiln, is a well-known method of preser- vation Apples and peaiy of large size should be cut into thin slices. From 5 to 6 meas. lire? of fresh apples, and from 6 to 7 of pears, affbrd in general one measure of dry fruit, (biffins). Dried plums, grapes, and currants are a common article of commerce. Herbs, cabbages, &c., may be kept a long time in a cool cellar, provided they are eovered with dry sand. Such vegetables are in general preserved for the parpoMS o( PUTREFACTION. 617 food, by means of drying, salting, pickling with vinegar, or beating up with sugar. Cab. bages should be scalded in hot water previously to drying ; and aU such plants, when dned, should be compactly pressed together, and kept in air-tight vessels. Tuberous and other roots are better kept in an airy place, where they may dry a little without being ex- posed to the winter's frost. A partial drying is given to various vegetable juices by evaporating them to the con- sistence of a sirup, called a rob, in which so much of the water is dissipated as to prevent them from running into fermentation. The fruits must be crushed, squeezed in bags tc expel (he juices, which must then be inspissated either over the naked fire, or on a watcx or steam bath, in the air or in vacuo. Sometimes a small proportion of spices is added, which tends to prevent mouldiness. Such extracts may be conveniently mixed with sugar into what are called conserves. Salting is employed for certain fruits, as small cucumbers or gherkins, capers, olives, tc. Even for peas such a method is had recourse to, for preserving them ascertain time. They must be scalded in hot water, put up in bottles, and covered with satuiated brine, having a film of oil on its surface, to exclude the agency of the atmospheric air. Before being used, they must be soaked for a short time in warm water, to extract the salt. The most important article of diet of this class, is the sour kraut of the northern nations of Europe (made from white cabbage), which is prepared simply by salting ; a little vinegar being formed spontaneously by fermentation. The cabbage must be cul into small pieces, stratified in a cask along with salt, to which juniper berries and carui seeds are added, and packed as hard as possible by means of a wooden rammer. The cabbage is then covered with a lid, on which a heavy weight is laid. A fermentation commences, which causes the cabbage to become more compact, while a quantity of juice exudes and floats on the surface, and a sour smell is perceived towards the end of the fermentation. In this condition the cask is transported into a cool cellar, where it is allowed to stand for a year ; and indeed, where, if well made and packed, it may be kept for several years. The excellent process for preserving all kinds of butcher meat, fish, and poultry, first contrived by M. Appert in France, and afterwards successfully practised upon the great commercial scale by Messrs. Donkin and Gamble, for keeping beef, salmon, soups^ &c. perfectly fresh and sweet for exportation from this country, as also turtle for importation thither from the West Indies, deserves a brief description. Let the substance to be preserved be first parboiled, or rather somewhat more, the bones of the meat being previously removed. Put the meat into a tin cylinder, fill up the vessel with seasoned rich soup, and then solder on the lid, pierced with a small hole. When this has been done, let the tin vessel thus prepared be placed in brine and heated to the boiling point, to complete the remainder of the cooking of the meat. The hole «f the lid is now to be closed perfectly by soldering, while the air is rarefied. The vessel it then allowed to cool, and from the diminution of the volume, in consequence of the reduction of temperature, both ends of the cylinder are pressed inwards, and become con- cave. The tin cases, thus hermetically sealed, are exposed in a test-chamber, for at least a month, to a temperature above what they are ever likely to encounter; from 90= to 11(^ of Fahrenheit. If the process has failed, putrefaction takes place, and gas is evolved which, in process of time, will cause both ends of the case to bulge, so as to render them convex, instead of concave. But the contents of those cases which stand the test win infallibly keep perfectly sweet and good in any climate, and for any number of years If there be any taint about the meat when put up, it inevitably ferments, and is detected ia the proving process. Mr. Gamble's turtle is delicious. This preservative process is founded upon the fact, that the small quantity of oxveen contained withm the vessel gets into a state of combination, in consequence of the high temperature to which the animal substances are exposed, and upon the chemical principle, that free oxygen is necessary as a ferment to commence or give birth to the process of putrefaction. I shall conclude this article with some observations upon the means of preserving water fresh on sea voyages. When lone kept in wooden casks, it undergoes a kind of putrefaction, contracts a disagreeable sulphurous smell, and becomes undrinkable. The influence of the external air is by no means necessary to this change, for it happens in close vessels even more readily than when freely exposed to the atmospherical oxveen. The origin of this impurity lies in the animal and vegetable juices which the Water originally contained in the source from which it was drawn, or from the cask, or insects, &c. These matters easily occasion, with a sufficient warmth, fermentation in the stag- nant water, and thereby cause the evolution of oflTensive gases. It would appear that the gypsum of hard waters is decomposed, and gives up its sulphur, which aggravates the disagreeable odor ; for selenitic waters are more apt to take this putrid taint, than those which contain merely carbonate of lime. As the corrupted water has become unfit for use merely in consequence of the admu 518 PYROGALLIC ACID. ^^i^L • TIJ °*"^"' ^?'' '^^*^' ^" ^^^^'^ i« "ot liable to corruption, so it roar on purified again by their separation. This purification may be accomplish^ most eLilr d^J^nTl '\^"'T i!l'-«"^V<^h«'-<^o«I powder, or throu^Hh^powder of rS Sltclt S^fato th; J*"' <^-bon takes away not only the finely diffused coVrnpt Sm about ^0 drnn! "tn T' '""TT'' ■ ^^ ^^^^"^ *° '^^ ^^*^" « ^^^-^ l^^le sulphurk b^iaved Undoubted V f, P°"f ?; L«witz says that tv.o thirds of the charcoal may oe saved. iJndoubtedly the sulphuric acid acts here, as in other similar casp«! hi Lnd r°T'^''"';/"^ '"P"™*^"" '^'''' albuminous matters, combing wiiHfi^^ and rendering them more apt to be seized by the charcoal. A more effectual aS ^ lA'^T^'f '? ^.^ ^^^"^ ^"^^'' ^^ '^ ^' ^«""d »" ^l"'"- A drachm of pound^ a!um should be dissolved with agitation in a gallon of the water, and then left to S"Quie"S may L 'p^'r'ed tfT^^'rHT !""''' '' 'u' "^1^"™' "'L"1^'^ ^"^''^ ^^-'"^^ clea^r atT, and may be poured off. The alum combines here with the substances dissolved in the water as it does with the stuffs in the dyeing copper. In order to decompose any alum w h ch Sd^ to ii." '" ""' ' equivalent quantity of crystals of carbonate o/s^a may ^ The red sulphate of iron acts in the same way as alum. A few drops of its solution are sufficient to purge a pound of foul water. The foreign matters dissofved in the wa^^^^^^^ which occasion putrefaction, become insoluble, in consequence of oxydizement Iike7e-e teble extractive, and are precipitated. On this accounlTalso, foul water may be purifif? frlsh"aT'so'S'.n"r \''r'^' '^ with bellows, or by 'agitating it TLma'ct S fluencP nVll a' ^?'^-^^ *'^ ^""^'^^ *° ^^y^^"' ^^""^ ^« ^^^ explain the in- fluence of streams and winds, m counteracting the corruption of water exposed to them Chlorine acts still more energetically than the air in purifying water. A Httle aqueout* ^l^aTe: itt m^ilTe^"' ^^ ''' ^^^"^"-^ ^' ^ ""^« ^— chlorinelr^o^uTh ?C Water-casks ought to be charred inside, whereby no fermentable stuff will be extract- or Sn'.r^* ,^"'''? '^'P^' ''^^"^^'•' *^^ "°^ ^«"°^«'»^y provided with i^on t?nk; for holdins their water in lonsr vovages. is nSuS' if^oTpt bisulphuretof iron. Copper pyrites, called Culgarly mundick, Jlm'sfGlJi^, ' Tv'";- (f *^-' /'y-^-i^'^^. -Acetone, Fr. ; Brennzlicher Essig. geist Mesit, Germ ) This liquid was discovered and described by Chenevix Ion- before pyrohgmaus spirit was known. It may be obtained by subjecin- to drv disUllf Hon the acetates of copper, lead, alkalis, and earths; and a J it is formed esp7cialydun^ thesecond half of the process, the liquor which comes over then should brset anaJu separated by decantation from the empyreumatic oil, and distilled a second t me by the heat of a water-bath. The fine light fluid which now comes over first, is to be rectified along with carbonate of potassa, or chloride of calcium. As pyro-acetic sniril usually retains, even after repeated distillations, a disagreeable empvreumatic smelf like r^-' H ^'k^'T'^ bone-black should be employed in its final recUfication Tccord ng to Reichenbach, pyro-acetic spirit may be extracted in considerable quantity from beech ?„'• ^f^'i^K""^' T'^'-^ P' '^''"' '•^"^ P^^P^^^^ '^ « ^«l«rl^«s limpid ?"ufd of ^crid and burning taste at first, but afterwards cooling; of a penetrating aromatic smdl, different from that of alcohol ; of the spec, gravity 0-7921 at 60° R.^b^iH^ a^ fA\lo^ remaining fluid at 5°. It consists ultimately of-carbon, 62-148 hvdrL gen, 10-453 ; oxygen 27-329 ; or, of 1 proportion of carbonic acid + 2 prop of o'efian^ f^' t ^'Z ''^^''^''' ?'' ^ P^'^P- ^^ «'"''" ^^'^ - ^ P'-^P- «<• carbonic acid. AccorO^ i^488 TnuZ "'''"' !! •' ^P'^Pf H«f 51-52 parts of concentrated acetic acid, and 48^488 of oil of wine, being double of the quantity in acetic ether. It is very combu^ tible, anu brims with a brilliant flame, without smoke. When treated by chSeU llonl T fif" ''^\''- ^y^'^^^'^' ^"d absorbs 2 atoms of chlorine. It is soluble in watVj alcohol, ether, and is not convertible into ether h,r strong sulphuric acid. It is u.^' luflened ""^ '"''"' commonly called gums, with which the bodies of hats a^ PYROGALLIC ACID, and sotne astringent substances which yield it. To procure the pyrogallic acid for examination, powdered nutgalls are treated with water; which w evaporated until an extract resembling catechu is obtained, which being sublimed in Mohr 8 apparatus gives about 10-3 per cent, of pure crystals of the acid. By aaalvsis It was found that 0-312 yielded 065 carbonic acid, and 0-1345 water; thia would to 8 carbon 4 hydrogen 4 oxygen 611-480 calculated 67-61 49-918 do 4-70 400000 do 87-69 found 57'60 do 4-78 do 37-62 PYROGALLIC ACID. 519 In exanaining the substances which yield pyrogallic acid, Stenhouse states, that he TOuld obtain pure tannin only from nutgalls, let his process be ever so carefully conducted Pure tannm and gallic acid are the only substances which are known, by distillation, to yield pyrcgalhc acid. Taking advantage of this circumstance, he proceeded to test various substances for the presence of gallic acid, and to examine whether the tannin they contain is the same as that of nutgalls. Sumach. Sumach, obtained from the small branches of Rhus coriaria, was digested m hot water, filtered, evaporated, and subjected to distillation. The flqid distilled over into the receiver gave no crystals of pyrogallic acid (owing to the empyreumatic oil and impurities passing over with it); but it evidently contained the acid and tannin, similar to that of nutgalls, an hypothesis which his subsequent analysis verified, for after treating a watery extract with alcohol, and again with ether, he obtained pure colourless crystals, which answered to the qualities of gallic acid, and on distillation yielded pyrogallic acid. The tannin freed from gallic acid, subjected to distillation, yielded as much pyrogallic acid as the same quantity obtained from nutgalls would have given. He also succeeded in converting the tannin of sumach into gallic acid, by boiling it with dilute sulphuric acid. In treating tannin precipitated from sumach by sulphuric acid with alcohol and ether, he procured crystals of gallic acid ; sumach, therefore, most closely resembles nutgall, for which it has long been a substitute in the arts. The quantity of tannin it contains is, however, considerably less. Valonia. The acorn of Quercus cegilops. Dried extract of valonia gave on distilla- tion no signs of pyrogallic acid: a concentrated solution was precipitated by size— the fluid was evaporated— the extract boiled with alcohol— the alcohol distilled over— and the extract treated with ether, yielding a small quantity of crystals having the properties of gallic acid, which, on distillation, gave pyrogallic acid, but in very limited quantity, alwut oiie-thirtieth of that of sumach. The solution of valonia, treated with sulphuric acid, gave but a trifling precipitate of tannin ; distilled, it gave much charcoal, but no empyreumatic products. The fluid in the receiver was colourless, and had no traces of pyrogalhc acid. The tannin of valonia differs materially from that of nutgalla Oak-Bark. The extract, treated as the former, gave no traces of pyrogallic acid • even in subjecting large quantities of a decoction to examination, he could not obtain crystals of gal 10 acid, which he concludes to exist in it in very minute quantities, if it exist in "• ,.,V^^. ^""^? precipitated by sulphuric acid yielded no traces of pyrogallic acid on distillation, and appears, therefore, to differ from that of nutgalls. i>it;t-i>iwi, imported from Carthagena, is the pod of a leguminous shrub, the Ccesal- pima cortaria according to Balfour. The extract, subjected to distillation, yields no traces of pyrogallic acid ; but the fluid, passing over into the receiver, has its character- istic signs By treating m the manner above mentioned, pure crystals of gallic acid may be obtamed from it which, on distillation, yield pyrogallic acid. Sulphuric acid gave^ with a concentrated solution, but a very small precipitate, which, dried and dis- tilled, yielded no trace of pyrogallic acid, but much charcoal. Thence the tannin of divi-divi diff-ers materially from that of nutgall. The quantity of mucilage which it contains prec udes it from the use of dyers; but as it contains much tanninlt is lar-elr used for tanning. ' *~o^»j Kino. From the African kino he could obtain neither gallic acid, nor did the abun- dant precipitate produced by sulphuric acid, on distillation, show any traces of pyro- gallic acid ; nitric acid converted it into oxalic acid. ^^ Catechu Catechu contained no gallic acid, but catechu and a peculiar tannin, which 18 precipitated by sulphuric acid and when boiled with dilute sulphuric acid is of a dark brown colour, ike the tannin of oak-bark. It is insoluble in cold or hot water alcohol, or ether and but trivially soluble in a solution of strong alka Us. DistilT^Ti gave no traces of pyrogallic acid or pyrocatechin xjiBuuea, u cat^echi^? zt'en^^^^ '^'""^^ ''''"^"^^" ^° '"^^ ^^*^'' ^''^^' «° distillation the pyro- Salicin. Charies Gerhardt was induced again to undertake the analvsis of this lllld'strli." '"'"' '^ '^' modification of lie atomic numtr of car£^^by Du^ In 100 parts he found Carbon Hydri^en - Oxygen - I IL 65-28 55-24 6-50 6-63 38-22 38-23 1061-898 100-00 lOOlM) 100-00 10000 m u (If ! i PYROLIGNOtrS ACID. He quotienU of th«« number^ dialed by the .tomic w.ighl^ .„, Carbon Hydrogen Oxygen At 1474 1040 882 48 28 22 in 100 ports 55-3 6-2 S8-5 PTROLTGNITE OF LEAD tk« « r •f sugar of lead, ought to l^ tolerabfv^JJe&L"'''^ ^^^^^^^^ '" *^« manufacfnre Jield a good product^ The manVfacturerrof TrS^'^"^^^^^^^ substances, in order to name of rauriute of lead) a produc^^whTch is ve7v h^^^^^^ ^"'°'^*^ <*^^^«» ""^^^ t^* tares, and which ia prepare/bv satumtW ^tlf ^ brown by these empyreumatic adraix- printing. sugar of iLd'ia lieLu^^tr^^tlT".-''^ T'^' ^'''^^'^- I" clyeing^nd impure sugar of lead is prejuSi^r^ the morH^ ^''''" ?^ *^^*^*^ ^^ alumi/a; but as pared from alcohol vinegar ^aioneLe^^l^^^^^^^ ^" r^^. P^^e sugar of le'ad. pre- yellow. chrome orange, ^ ^ employed for these, as weU as for chrome 4t obSS^p^^Str ^^^^^ f r ^ ^^ -^-»^ the sugar of lead The rough Pyrolignous'^S Ts ^1.6^ h, the t^l ^^^^^^^^ riaked lime, and exposed to the air for V if. i ^ "°^'; .t*"^" supersaturated with frecjuently stirred up^ By the ex^l of 1L.TI *;"°S^,^J'<^J *!««« the mass is to be Jbich forms with the limeVmore or ess^^^^^^^ the empyreumatic matter. The e^Dosure to the air is necesLry Lc^uL Z^ oxidised, assume a deeper colol^rindZZ.LTr^'''^''^!^ "^'^^ers become more brown solution of the acetate of Hmpio^ ^"^^ ?": combination with lime. The precipitate, and heated to £ Ll Xnl^U ""^!r'^ ? " «"'*«*>^« »»«"°«'* ^o^ the W are successively addS rion^asThe l^uTi 'n^^ " clear solution of chloride of evaporatmg to dryness, the yellowTsh Jav S. i!"f ' to become paler. After with a smaU proportion of chloridrnf ii -^ ^ ^ ' ^^'''^' """^^'^^^ «^ "^etate of lime acetate be intenrd to be obtS bv d1 t nTr " t^^^r^^ by sulphuric acid. If^e must be diluted with an equalvoTumLf wat^^^^ ^'""^ ''^" °"'^*"^«' *^« ^^^P^^""^ «<^id -^ff^t^^^^^^^^^ or only very slightly so, and « left standing for a short tim^e U Tthen to Z H 1^ I a ^"^f^^mn of heat. Themixture drawn off from the gypsum. li this case U is nf L^^ • with water, and the clear water phunc ac d with water «<, ♦».« r!t ^ "**' advisable to prev ously dilute the mil with difficulty, an7l:;\:Lf mKu'd*''" "^""^^ ^ crystallioe^oose J,ditLt subsfdi -id"; an5,rtL*treTt:'at"rfr„^^ ^"r*^*y "^ «"--*'« -•<^' -^- -Ip^nrous added and heat applied "KtiVr'acto 7 ^^^^« "^^^^ '^^ »- toZ acid from the gypsum and also «, lr^w Ti !i f* .. Precipitate retains sulphurous acetate of leafylld^a^owi A^^^ and chlori/e of lead. The solutio? of tS Jead but which is gener^^fy s^lXnurl for' 5^"*^"""^ ^ «"^^» Po^tion of chforide of purified by recrystallization ^ ^ '^ ^^^^ *^^^'"^ purposes, and can be still further I Zf ?e^IK^ t^fp'r^^^^^^^^^ ba> been said under Ac... Ac. Manchester. The retortHnf ca^ imn 1^fp?t""i * ^''Vl^l' «^ «" establishment ne^ Two of these cylinders are h^a^LlTy re h.VthVfl^^^^^^ 1 ^"^^^ ^" ^'-"^^e^ and upper surface; but the bottom is shield^ bv firp ,1 7""^ H^^'l^ '"""^ their sid^w fire. 2 cwts. of coals are suffickSt o crmnlet^thpr n ?'''" V^' ^^""^^^ «^»'on o*'
' ^^^^^^^ is rectified by two or tnfee Ji?;a^rJsarut%°,^^^^^^^ -bjeeted to distillation b, quicklime, and subsequent a/itationwitlwa^er^ ^" ^"'''^"^ ^^ re-distillation with whTch%ra'r;^f.pt%^^rtt*:i!!^h%^^^^^^ -'^ - '^ ^-^--pper, up with the heat. Vhe fluidXound ttt pt^:^^^^^^^^ 'j'^f --' - ^^ iVoths* and mixed with a quantity of alum equivalenfto its siSn^pr^ f^"" *"5^'***'' ^^^P*''* liquor, or acetate of alumina, of the cali^nrintPr tII^I*'' '" ^'!^^'' *° ^°™ tbe red alumina and potash, mutually decomno ^rch o.h^r ^k^^^^^ '""^VhRte of lime, M'hich falls immediately to 'heTttom ' ^^^ *^^ formation of sulphate of M. Kestner, of Thann, in Alsace, obtain's, in his manufactory of pyroligneous acid, 6 PYROLIGNOUS ACID. 521 hectolitres (112 gallons imperial, nearly) from a cord containing 93 cnbic feet of wood. The acid is very brown, much loaded w^ith tar, and marks 5° Baume ; 220 kilogrammes of charcoal are left in the cylinders ; 600 litres of that brown acid produce, after several distillations, 375 of the pyroligneous acid of commerce, containing 7 per cent, of acid, with a residuum of 40 kilogrammes of pilch. For the purpose of making a crude acetate of lead (pyrolignile) he dries pyrol ignite cf lime upon iron plates, mixes it with the equivalentdecomposingquantity of sulphuric acid, previously diluted with its own weight of water, and cooled ; and transfers the mixture as quickly as possible into a cast-iron cylindric still, built horizontally in a furnace ; the under half of the moulh of the cylinder being always cast with a semicircle of iron. The acetic acid is received into large salt- glazed stone bottles. From 100 parts of acetate of lime, he obtains 133 of acetic acid, ai 38^ Baume. It contains always a little sulphurous acid from the reaction of the tar and the sulphuric acid. The apparatus represented in/g*. 11 96 and 1197 is a convenient modification of thai exhibited under acetic acid, for producing pyroligneous acid. ii%. 1196 shows the fur nace in a horizontal section drawn through the middle of the flue which leads to the chimney. Fiff. 1197. is a vertical section taken in the dotted line x, x, of /^. 1196. The chest a is constructed with cast-iron plates bolted together, and has a capacity of 100 cubic feet. The wo(k1 is introduced into it through the opening 6, in the cover, for which purpose it is cleft into billets of moderate length. The chest is heated from the subjacent grate c, upon which the fuel is laid, through the fire-door d. The flame ascends spirally through the flues e, e, round the chest, which terminates in tlie chimney/. An iron pipe ^r conveys the vapours and gaseous products from the iron chest to the con- denser. This consists of a series of pipes laid zigzag over each other, M'hich rest upon a framework of wood. The condensing tubes are enclosed in larger pipes f. t; a stream of cold water being caused to circulate in the interstitial spaces between them. The water passes down from a trough k, through a conducting tube /, enters the lowest cylindrical case at m, flows thence along the series of jackets «, t, i, being transmitted from the one row to the next above it, by the junction tubes o, o, o, till at p it runs ofl" in a boiling-hot state. Tlie vapours proceeding downwards in an opposite direc- tion to the cooling stream of water, get condensed into the liquid state, and pass off at y, through a discharge pipe, into the first close receiver r, while the combustible gases flow off through the tube «, which is provided with a stop ci^k to regulate the magnitude of their flame under the chest. As 8ontamed les. real spiri? w^kin-rorLtr.r.I'oVoTn^'^^^^^^ "t'-"' - ^e «verag. tons of wood has only yielded Ifin 3i^J! r another a weekly consumption of 80 gallons have been obt'Li^'from 36 f^s of woS""^''' ''^'"^ ' *"^ '' * '""'^'^ ^^^^ '^ ^^^^elj;7.^:-^^^^^^ acetate of lime is of two saturating with lirae eithe? th^ dis^illpd nnl^ w '"^ ^^^ ' *^^«« ^'^ obtained by after pyrSxylic spirit hTb^en remoy^ by S^^ mentioned, or the undistilled aciS almost to dryness^^or by eyrporatT^Tl^,nf„f "'^ "l ?** ^T^porating the clear solution in the case in which tl^ crEc S\as Wn n^^^ • u^'/^" ^''•"" ^^ ^^«"^ *^« ''^^ lation of the spirituous product TT^i, Z "^"*^^^^^f ^1*^ lime previous to the distil- distillation. or ?he disUll^d acid, or^e unSllTdldd' .^^^*^^?"d- -<^^^ Previous to the same manner. The add linnnr ;« L i • ! *^*^' *^ *" ^^^^^' case performed in capacity say from 5oS to Too^ga^L^^^ or iron yessels o7conven1eit of skked and sifted lime, previous ly ma^^^^ ""^ ^'^^^' powdered chalk or added until the blue ™ W of S,f 1^^ '""^^ the consistence of cream with water is lime is then added. ^Jita ^few To reXthe°'J"°!' reddened ; a slight excess of complete. A portion of the tarry mattolfr ?«P«fation of the oily matters more of tCe chalk ?r lime empW^^^^^^ *" *^ ^'^^ ^ith the impuriti^ floats CHI the surface, and Vremryed^byskim^^^^^^^^^ ^^« ^•'"e. when clear, is ready for the evaporating nn^o ?• u ^^^^^^n of acetate of lime. with lead, and furnished whh coUg oJ^I P^m^^'"^ ?'^ ^'^^^' ^«°<^«" ^^«-^«l« lined boiler, or shallow pans of sheet iron Jt "5 ^ron steani-pipes in connexion with a repeatedly skimmej^ to remrve he terry matL^floTr''^ ^'T'^'' *^"'"^ ^^^^'^n '*« as fixst as formed, is fished out by Ss of W. !?-°^ ''^ ^" ^^''^^^^ ' '^^'^ ^^'^ ««!*. Uskets suspended oyer the pans/so th:?^ ^^ ^^1^^ t^ Jt L^ Z^^ PYROLIGNOUS ACID. 525 allowed to cool. The following practical result was obtained by the use of three sheet iron pans about 18 inches in depth, and capable of containing 450 gallons of acetate of lime liquor each. First six days of 24 hours each, 7020 gallons of liquor were evapo- rated, producing 78 cwt. of diy acetate of lime. Second week, 8060 gallons were evaporated, producing 92 cwt. of dry acetate. Third week, 7000 gallons were evaporated, producing 78 cwt. of dry acetate of lime. Two of the pans contained brown acetate of lime liquor, and the other grey acetate liquor. Tlie next part of the process is the drying of the drained acetate of lime. Tliis is usually effected by placing it on the top of the mass of brickwork in which the retorts, or cylinders, or ovens, are set ; but as there is seldom room to dry the whole of the salt in this way, many works are furnished with a drying house in addition, and, where the lime is made on the spot, the waste heat from the kiln or furnace is made available for drying the acetate, it being made to traverse the flues beneath the floor of the drying house. As a general rule, however, the drying of the acetate of lime is a part of the processes of this manufacture by no means well executed, requiring as it does more attention than the workmen are usually disposed to give to it. Turf forms the best material for fuel, as it does not burn rapidly, and produces a steady and equal temperature. Drying of the acetate of lime. When the furnace is thoroughly and equally heated, the flame of the fire is allowed to subside. If wood is employed as fuel, the sliding door should be opened at the commencement in order to allow the moisture to escape. The salt is transferred from the evaporating vessels to the drying plate, and spread out to the depth of 2 inches ; and after the first portion has become somewhat dry, the depth is increased to 4 or 5 inches ; the heat is preserved at the degree already mentioned for 24 hours, and during this time the salt is turned several times ; subsequently when the mass appears to be becoming dry, the temperature may be increased to 100° (257° R), so as to dry it completely. The mass is dry and properly roasted when it possesses the following characters. It must, before cooling, be brittle, easily crumbled between the fingers, mixed with blackish carbonaceous points or streaks, between which appear pieces of dry salt. A solution of the comminuted salt, in 4 or 6 times its volunae of hot water, possesses a yellowish brown colour with a dark tinge, while previously it had a reddish brown colour. When the heat is increased towards the end of the process, as described, care must be taken to do it gradually, so that no smoke shall rise from the acetate, because it might thus be decomposed. Neither must any spark be permitted to come in contact with the acetate of lime ; because, like sugar of lead, it possesses the property, in these circumstances, of catching fire and burning — by which the whole dry preparation would be completely destroyed. The treatment of the acetate of lime in this manner, by means of gradual drying, as experience has shown, possesses many advantages over the method of drying the salt in an open vessel ; because there is no loss of acetic acid, as always occurs by the latter process. The operator has the prepa- ration C4)mpletely in his power, and with little expense of fuel and time, many hundred- weights of the salt can be prepared at once. This process does not merely extend to the removal of the moisture from the acetate of lime, out a chemical influence is exerted by means of it ; because it is certain that the substances formed by dry distillation, which have been recently distinguished by Reichenbach, are partly dissipated by the heat, and partly decomposed, the acetate of lime possessing very different properties before and after the process. After the process, the salt does not imbibe water so readily as it did previously. After solution, filtration, and evaporation, a much purer product is obtained than liefore, and upon the filter a resinous matter remains, the constituents of which have not yet been examined. Part V. — Manufacture of Pyro-acetic spirit ^ or acetone. The usual mode of obtaining pyro-acetic spirit is by the decomposition of the acetates by means of heat. For this purpose the acetate is submitted to dry distillation in a retort, great attention being paid to the temperature, which should be kept as low as possible, consistent with the decom- position of the acetate employed. The distillation should be conducted with a slowly mcreasing heat, as the quicker the temperature is raised, the larger is vhe quantity of pyro-acetic spirit destroyed ; carbon remains in the retort* and the empyreumatic oil formed renders the spirit impure. In the case of the metallic acetates, water, acetic acid, and pyro-acetic spirit, pass off in a state of vapour, and are condensed ; carbonic acid and carburetted hydrc^en gases are the incondensable products, whilst the metallic base, mixed with some carbonaceous matter, remains in the retort. The metallic base is usually reduced to the metallic state, and the more difficult this reduction is, the greater ia the quantity of pyro-acetic spirit formed. Acetates, tne bases of which contain carbonic acid at a red heat, produce, when heated in close vessels, the carbonate of the base and acetone. This takes place, for example, with the acetates of potassa, soda, and baryta. Where the oxide cannot retain carbonic acid at a red heat, as in the case of acetates of magnesia, zinc, or manganese, tb« phi hf I ! mi 526 PYROLIGNOUS ACID. acetate is accompanied by carbonic acid. If the oxide be easily reducible as in the acetatei of copper, silver and mercury, there are given oflF hydrated^acetlacTd carbonic o^^^ acetates. The following extract shows the quantity of pyro-acetic sp^it oltl^ned Acetate of silver da do. do. copper nickel do. do. da iron lead zinc manganese 0-00 Oil 020 0-24 0-55 0-69 0-94 proportion of pyro- -.^ ^ -f fr P°^^^ f"^^ ^'""^' ^"^ ^"3^** y^^^d a n^uch larger proportion ot pvro. acetic spirit than any of the metallic acetates, and are therefore generally cmpWerf^ this purpose more especially the acetate of lime. It would appear that^the acet^ates of silver and of baryta stand at the two extreme points of the list^f acetates in rl^t^o the production of pyro-acetic spirit ; the former yielding only a concentrated a.^t^acd with not a trace of spirit, wtiilst the latter yields a liquid product a most ertird^ spirituous, with scarcely a trace of acid. The acetate of copper also yields but a smaft Dumas submitted to dry distiUation 100 parts of acetate of baryta, composed of Baryta Acetic acid Water 560 37-4 ' 6-6 1000 The result of and capable, therefore, of yielding 215 per cent, of pyro-acetic spirit several experiments gave the following products :— ^ Carbonate of baryta - - . . Charcoal ----- T Pyro-acetic spirit - ... * Water - - ... I Gas and loss - - - . " 1000 T.«S"nf'r"P^''*''"!**'**.*^° P^'^°^^ o^*^^ ^^^^'•^o^^ "o«e from the decomposition of a C „^J Pyro-acet.c spirit, tfi ere would be about two per cent, of spirit t7l^added tS 1 8 np^.' 7 '^ ^^W g've near about the theoretical quantity. Taking the product at 18 per cent one cwt of acetate of baryta should furni8h^2i gallons of pfro aS sd rft 2.. Z u '\T-^ ^ft""' •' ^^^^'"^^ fro^ *^« o^d'"«»-y «««tate of lime Jrcommerce^nd the results obtained by operating on some tons of this salt did not give evSX amount of produce, no doubt on account of sufficient attention not havinXen Jiven o the due successive distillat ons over quick lime, when a limpid colourlerfluid Ca t-a^ ?92^^ ^^poduced. It IS «,luble in water, alcohol, a'nd ethe., and' bl? wi^l': tS or IVoUnn^ifT^ ""^^^fZ^A' "^ r''^' ^''?«/«<^'«'-'' of the brou,n acetate of leaa '•un in UDon it whilst hnilino- fi^f l^i ^V®'^?'^'^®' about three times its bulk of water ia to tne surface ; when they are removed, the evaporation goes on as before If t e J f, fon t« st.U too much coloured, another dose of "Crater mfst be given A litde p^U^ . - 1 PYROLIGNOUS ACID. 627 toon enables us to know where the evaporation should be checked. The onlinary \iiotb<^d is, to rinse a ladle (which is used to skim off the tar from the solution) through tlu» liquid, and observe how mkny drops of solution fall from it before the solution taki's a stringy appearance ; if only 10 or 12 fall, then it is strong enough. The liquifl is* now ladleU out into malleable iron pans, 5 ft. long, by 3 ft. broad, and about 6 inches deep, the sides being bevelled, or sloping outwards, from below upwards, to crystallize. After l>e- coming sufficiently firm, the sugar of lead is taken out by inverting the pan on a cloth. The pots used in the above process are heated only at the bottom. Manufacture of the white acetate of lead. — This is prepared by dissolving litharge in acetic acid ; the acetic acid is first placed in a vessel, and the litharge added by degrees, well stirring the mixture until the solution does but slightly redden litmus paper; a quantity of water, equal to about one-half of the acid* employed, is then run into the lead solution ; heat is next applied, and the mixture slowly evaporated for about 12 hours, or until it has acquired a density of about 1-600. During evaporation any impurities which rise to the surface are skimmed off, and when the solution has acquired its proper density, it is run off into the crystallizing pans. When the mass of crystals has become sufficiently hard to allow of its removal en masse from the crystallizers, it is drained and placed on wooden racks in the drying house, and when dry, cleaned and broken up into u'agments for the market. The mother liquor, containing neutral and basic acetates of lead and other metallic salts, may either be treated with vinegar, evaporated, recrvstallized, and the residue employed as washings in subsequent operations, or it may be decomposed by carbonate of soda or lime, and used as carbonate of lead, or dissolved in acetic acid, and the superuatent acetate of soda or lime recovered. Tlie vessels employed in the manufacture of acetate of lead are in most cases made of lead. In Wales the mixing pans are of lead f of an inch thick, 7 ft long by ^ ft wide, and 1 foot deep. Those pans are set on iron plates over arches, and the fireplaces are outside the building, m order that the acetate may not be darkened by the sulphurous vap)urs from the coal. The crvstallizing pans are of wood lined with thin copper, and are about 4 ft. long by 2 ft wide, and from 6 to 8 mches deep, sloping inwards at the edges. At Pitchcombe the mixing and crystallizing vessels are both of copper, having a strip of lead soldered down the sides and across the bottom of the vessel to render the copper more electro-negative : there is thus no action on the copper from the acetic acid. Great care is requisite in the drying of the sugar of lead ; the temperature of the drving house should not exceed 90° Fahr. In Wales the heated air of a stove placed outside the drying house is conveyed through pipes passing round the interior ; at other places steam heat is employed for this purpose, which is much to be preferred on account of its being more easily regulated. We now come to speak of the product of sugar of lead from a given quantity of li- tharge. 112 lbs. of good Newcastle litharge should produce 187 lbs. of sugar of lead by the employment of 127 lbs. of acetic acid of spec, grav. 1057, but not more than 180 lbs. is obtained in practice. In one set of works in Wales, a ton of Welsh litharge produces with the acid obtained from 1 ton of acetate of lime, from 28 to 30 cwt. of sugar of lead * and in another manufactory 1 ton of best Newcastle litharge, with the acid from 1 ton and a half of acetate of lime, produced 33 cwt of acetate. ecut The following process with metallic lead, recommended first by Berard is easilv ex- uted and is said by Runge to yield a good product with great economy. ' Granulated lead, the tailings in the white lead manufacture, Ac, are put in several vessels (say eio-ht) one above the other, on steps, so that the liquid may be run from one to the other The upper one is filled with acetic acid, and after half an hour, let oflF into the second after another half hour into the third, « accurately closed ^JiZfZt '^'J'a^ distillatory apparatus, liquid acetic acid (strong or weak, pure or impure) is converted mto vapour, which vapour is conducted by means of a dIm into the convoluted perforated pipe before mentioned, or between the red botZ^f the vessel and the perforated false bottom; hence the vapour passing through theTumLlu^^ perforations of the false bottoms and diaphragms, diSases r^elf^throuTeverriSrt^^^^ the vessel Its acid entering into combination with the base employed, and foTm^f the aceta e which falLs to the bottom of the vessel, and in its descent mLts SthTLsJend! ing streams of vapour, the acid of which renders it perfectly neutral- meanwhile the more aqueous parts of the vapour become liberated, and maintaining their temTrature ascend, and in the.r passage through the successive layers of the base are thereby d^S of their remaining acid. The vapour thus reduced to simple steam is allowed to escIS through one or more pipes at the top of the vessel; and as this stream still maintains a boihng temperature it is conducted through a worm to evaporate the acetate or the mother-liquor, by its heat. The distiUation of the acid is continued until the acetate in the vessel is arrived at the proper degree of concentration for crystallization, which ie easily ascertained by examining a small quantity drawn off by a cick at the bottom of letir' ^^^ ^^*'^'' ^^""^^"^ ^"^ discharged when the operation in com- As the operation draws to its close, by nearly aU the base having combined with the acid, the vapour issues out of the vessel, charged with a certain portion of acid ; and in order that no loss may be sustained by its escape into the atmospEere, it is conducted into another vessel, prepared like the first mentioned, but charged super-abundantly with the ^' ,x h "f ^'^^'^ P^'*'"^^, ^^ *^^ ^"'^ ^««"^S «"t ^^ *^« first vessel, until the opera- tion m that first vessel was ended. As the temperature of the solution of the acctatrcan never exceed that of the vapour, the crystalline product is of fine quality ./a V":-^^^"/^*^^'-^ 0/ acetic acid. In treating of the manufacture of acetic acid, we shall not enter upon any other processes, than those of the decomposition of the acetates, as effected either by heat or by sulphuric acid ^^f'^'^^^fi!'^ ''^^f'^i ^y decomposition of the acetates hy mean» of heat. -^Aromatic vine- gar We have already mentioned, whilst speaking of the produce of pyro acetic soirit that when the acetates are submitted to dry^distiultion, acetk acid is pureed l^rfol-' iZTn^o^f k""".! Z''*'^''^ ^'?^ *^/ 1*^^^ *^^" *1"«*^^' «^°^i°g the quantity of acetic acid obtained by the decomposition of the metallic acetates :— ^ Acetate of silver do. copper do. nickel do. inm do. lead do. zinc do. manganese 107-309 84-868 44-781 27-236 8-045 2268 1-286 The crystallized acetate of copper is the salt most usuaUy employed for this purpose. 20 pounds of the powdered acetate are placed in an earthen retort of the capacity of about two gallons, previously luted and exposed to the action of the fire ; the elongated neck of the retort is connected with a tubulated receiver, and this with a seconi and third the last of which is furnished with a Wetter's safety tube, dipping into water ^^wnK^l^^/^'S^'^!^""^.^??"^^ *^^° gradually Increased, and the operation regulated by the development of the gaseous products, which must not be too S)w or too fast. The receivers must be kept cool. When on increasing the heat it is found tS. .of/fT^^'L^- ^ ?r" °^' *^^.^/^ ^"«* ^ P«* ^"*' "^^ thelpparatus left to cooL TTie acid thus obtained has a greenish colour, its sp. gr. is 1-061. pl-om 20 lbs. of acetate ^I'^ff/nAilK^'T *^*° ^^ ^^^ **^'^"Sh ^^^ ^'•e obtained. The residuum in the retort T?>o i„l ^ ^'S! "^PJ^*: '",* P"^*^"^^ ****«' "^^^ ^^*h a small quantity of charcoal. Sfnf^llif J*^"\«b,t^.ned IS next placed in a glass retort of the^capacity of t^«l i^ ''rK*?u''^rS.^ 'I *^^P*'^ ^ tutulated receiver, and the retort is heated by means of a sand-bath. The first portions which come over are veiy weak, and the product should be kept separate until it comes over of a density of 1072; the whole of the remaining product is now collected together, and the distillation continued to dryness. Jn-! ^ f r' ^ 'P.- ^; °^ 1"^^^ ♦« 1"088. The weaker products are redistilled, and Oie stronger portions mixed with the former. The 9f lbs. of crude acid furnish ii^ ^ 1 n/.^ ^ ^T ^'1^' 'P'.^- ^'^^^' ^ P*»"°^« ** «P- g*-- 1-042, and half a lb. of sp. gr. 1 023. The small portion of acetone which comes over with the acid, imparts £ agreeable aroma to it, and the addition of camphor and essential oils constitutes the aromatic vinegar of commerce. PYROLIGNOUS ACID. 529 Manufacture of acetic acid, bp the decomposition of acetate of »oda hy sulphuric aeid. Any given quantity of crystallized acetate of soda is placed in a copper still, and a hollow place having been made in the mass of the crystals, a quantity of strong sulphuric acid. equivalent to 35 or 36 per cent, of the weight of the acetate of soda employed, is then poured in at once; the crystals forming the sides of the heap in the still are thea pushed down into the acid, and the whole stirred with a long broad wooden spatula; the head is then put on and luted, and the connection made with the refrigerator. Nearly 4 cwt of acetic acid, of sp. gr. 1 060, may thus be obtained from 3 cwt. of acetat* of soda, which only requires to be passed through a calico filter (of the form described in Mohr and Redwood's Practical Pharmacy, page 20Z,fig. 211), on which some animal charcoal has been placed, to fit it for the market. A small quantity of acetic ether is often added to flavour it. The still employed should be of stout copper, (the solder used in its construction should be silver solder), having its lower half set in an iron vessel, which either receive* the high pressure steam to be used as the heating medium, or contains oil. tallow, or fusible metal, according as either of these substances may be preferred for use. In the" former case a cock is placed at the lower part of the casing, to let off the condensed steam from time to time ; and in the latter case the iron jacket is placed over the fire ; the contents of the still receiving sufficient heat from the heated tallow, oil, or metal ■with which the copper still is in contact. A safety tube should be attached' to permit the rise and escape of the heated oil, * then producing a bcauUful blue colour wwTSo • f • ^"^P^""^ acid decomposes it, from the^atmosphe e ^d it Siv Hi « ^ ' '"*? *^!™f "' «« ^he acid attracts water carbon of aXrtv SL^rJlr T ^I'^m^'^ °" Pl«»'>ful dilution with water, leaving yellow a/e toTege't^ble'^r^^^^^^^^ ^^ ^"'T-"*'"^ ^^^^'^ -P-^s a permaneo! Q. «hrl™^?^L" **ha"°fKld ",L^^ "'.^r'f *'>'" ^ *» *« ■^fi-'^- »W with but is now prohibited under s^T^ ^SllU^ i{ Iff '*^^"^"^ > some brewers for hops. or poison fo? flies penalties. It affords a safe and efficacious fly-water, QUEEN'S WARE. See Pottery. me^cuiy ^^^^^ W» « ^ ^«««i "ame of Turbith Minera; or yeUow subsulphate of in S Amer?ca' ^^l ^"^ "* • ***" ^T '^^>«' ^' ^^"o^ ^t> » tree which grows and little in water^ S^lutfrof ^W 5 i ' ^T^^ soluble in alcohol, hardly in ether, QUICKLIME ; see Lme. QUICKSILVER ; «ee Mercury. covery an(f use of SmiSs wJ^ ^1'''''^^''^'"^ ^H^ ^^ «^'*^"»7' " ^« dis. QUICKSILVER. 53^ the gold, and imparts a white colour to it; at the conclusion the metal is volatilized in 4 •mall tube, to obtain it in the state of the characteristic fluid globule. After a comparative examination of the reactions for discovering mercury in its solu- tions, we are satisfied that the galvanic or galvanoplastic action is the most sensitive. We have been able to detect by means of this test the mercury in a solution containing o"ly TmrVmr **»• It is not the galvanic apparatus which Smithson invented that we employed in our researches ; we only preserved its principle. For toxicological researched, this ingenious instrument would have been subject to inconveniences, which we wished to avoid : we sub- stituted for the apparatus of the English chemist one in which the vessel containing the suspected liquid was inverted in a kind of funnel terminating in a tube drawn out to a bore which was almost capillary, so that the liquid might flow out of it at the rate of about a drop in 5 seconds ; it was caught in a capsule. The flow could be regulated by varying the inclination of the apparatus. The electro-positive pole was placed in the capillary tube, the negative in the wide part of the funnel ; they were placed nearly in contact, and both, or at least those parts which touch the liquid, should be made of pure gold. When the pile (Bunsen's), which consists of a single pair of plates, is in action, evolution of gas takes place at both poles, and the mercury contained in the solution is deposited upon the electro-positive pole, which it whitens. To be certain that this effect is produced by mercury, the metal need only be volatilized in a reduction- tube. Being certain of detecting the slightest trace of mercury with this apparatus, we still had to find a suitable process for separating the mercury from the organic matters, and to isolate it from them as far as possible without loss. The Academy approved of the process of carbonization by sulphuric acid proposed by us, and this process is now gene- rally practised in cases of medico-legal inquiry. We tested its application to the detec- tion of mercury, and succeeded in this without having recourse to distillation, as we at first feared we should be obliged to do. After numerous trials we adopted the following process : — At a temperature of about 212° we liquefy the animal matters by one-third or half of their weight of monohydrated sulphuric acid in the ordinary manner. This liquefaction being completed, which requires only an hour and a half, or at the most two hours, the capsule is taken from the fire and left to cool to a certain extent Then, • after having placed the vessel underneath a chimney with a good draught, to protect the operator against the disengagement of vapours, we throw into the black carbonized liquid saturated chloride of lime in separate pieces, stirring the mixture at the same time with a glass rod. By degrees, as the matter thickens, and becomes white, distilled water is added, which favours the action of the chlorine, and this is continued until the liquid to be separated by filtration appears almost colourless. The quantity of chloride of lime must always be very nearly in relation to the amount of sulphuric acid required for the perfect liquefaction of the animal matters. For 3 ounces of silver, on account of the bile and fats which the liver contains, sometimes 1^ ounces of sulphuric acid and H ounces of chloride of lime are necessary ; but it is scarcely ever requisite to exceed this proportion. Tlie substance, which is whitened and rendered of a chalky aspect, is well-moistened whilst cold with absolute alcohol, then diluted with distilled water and filtered, and the precipitate washed repeatedly. The liquid, if too abundant, is concentrated by evapo- ration, after which it is submitted to the action of a galvanic current, in the apparatus described. It was proved by experiment that the voltaic current favoured the precipita- tion of the mercury on the gold wire, and that in all cases it at least possessed the advantage of accelerating an operation, which without the concurrence of tliis action would perhaps require much time to accomplish. Tlie metal being obtained on the electro-positive conductor of the pile, it is necessary to wash the gold wire in boiling aether or alcohol to remove all fatty matter, and to dry it before introducing it into the reducing tube. This should be perfectly free from moisture, which might stain the globule of mercury, which is sometimes extremely small, and must be made perceptible to the eye. The efficacy and sensitiveness of this process has been ascertained by numerous ex- periments. We have required 3 ounces only of the liver of an animal poisoned with corrosive sublimate to obtain an appreciable quantity of mercury from it. In future therefore it will not be more difficult to detect corrosive sublimate than ai-senious acid, or any other metallic compound. — Comptes Rendua, March 31, p. 951, 1845. QUILL. See Feathers. QUINIDINE. — Put 100 grains of sulphate of quinine in a Florence flask with 5 ounces of distilled water ; heat this to brisk ebullition ; the sulphate of ouinine ought not to be entirely dissolved ; add 2 ounces more water, and again heat it to eoullition ; which ought to make a perfectly clear solution. If this be allowed to cool for six hours, and the crystals carefully dried in the open air on blotting paper, they will be found to weigh about 90 gr. ; the mother-liquor may be evaporated and tested with ether, when 534 QUININA. QUININE. 6SS any cinchonine (or ^ quinine) will be easily detected. On examining sulphate of Sln'a .r^;;^Tf ^Th ''"''^^ ^'"^!?^ manufacturera. I have fo^d allVthCgivl, The above quantity of water (7 ounces) readily dissolves 800 grs of sulnhate of qumine; and if 100 grs.. of this salt are dissolved in 1 ounces of wate^ihe cry uds dried J^r^^.Xar^ ^^ ^ '* ^''" ^'^"'''^ '^ ^"' ^" '^^"''"°' ^^^^ead of al^u^ 10 g^^^^^ QUININA. This medicine is now prepared in such quantities as to constitutP a chemical manufacture. Quinina and cin^cho^ina are two vVtab e at'ka^L wh d exi^ m Peruvian bark or cmchona ; the pale or grey bark contains most cbcl7^ ina a^ the yellow bark most qumma The methods of extracting these bases are very va;ious In general, water does not take them out completely, because it transforms th^e neu^m salts m the barks mto more soluble acidulous salts, and into less soluble sub-salts. To exhaust the bark completely, one or other of the following solvents is employed — w«L i. • .• ^^,^?'^^ci ty this menstruum is to be treated with ve;y dilute warm munatic acid, in order to dissolve every thing thus soluble ; the acid liqior is to be saturated with magnesia, by boiling it with an excess of this earth ; the precipitate 18 to be dried, filtered, and then exhausted by boiling-hot alcohol 2 Dilute acids Boil the bark, coarsely pounded, with eight times its weight of water containing 5 per cent, of the weight of the bark of sulphuric acid. Thi?treat- Sf^fiu" A ^ "^P^.^*^^ ^^^»» ? ^'f^ 5"antity of dilute acid. The whole liquors must f S^cX I ^f '^"""? strained, ancf the solution mixed with quicklime, equal to one fourth of the bark employed. This mixture, after having been well stirred, is to be strained, whenever it acquires an alkaline reaction, that is, tinges reddened litmus paper blue, or turmenc brown. Tlie calcareous mass is to be now washed with a little water, and dried and then boiled thrice with spirit of wine of sp. grav. 0835 Thi* solution being filtered, is to be mixed with a little water, and distilled. The bases cinchonina and quinma remain under the form of a brown viscid mass, and must be purified by subsequent crystallization, after being converted into sulphates S. An alkah, and then an acid— The object of this process is, to retain the vegetable alkalis m the bark, while with the alkaline water we dissolve out the acids, the colouring matters, the extractive, the gum. «fec. Boil for an hour one pound of the bark with six pounds of water, adding by degrees a little solution of ^tash, so that the liquor may have still an alkaline taste when the boiling is over. Allow it to cooL filter, wash the residuum with a little water, and squeeze it. Diffuse it next in tepid water, to which add by degrees a little muriatic acid, till after a prolonged digestion the mixture shall perceptibly redden litmus paper. Filter the liquor, and boil it with magnesia. The precipitate being washed and dried, is to be treated with hot alcohol which dissolves the quinina and cinchonina. Obtained by any of the above methods, the quinina and cinchonina are more or less coloured and may be blanched by dissolving them in dilute muriatic acid, and treating the solution with animal charcoal. ^ There are several methods of separating these two vegetable alkalis. 1. When their solution in spirit of wine is evaporated by heat to a certain point, the greater part of the cinchomna crystaUizes on cooling while the quinina remains dissolved 2. Digestion m ether dissolves the quinina, and leaves the cinchonina. 3. We may supersaturate slightly the two bases with sulphuric acid. Now as the eupersulphate of quinina is sparingly soluble, the liquor need only to be evaporated to a proper pomt to crystallize out that salt, while the supersulphate of cinchonina continues in solution with very little of the other salt. Even this may be separated by pre- •cipitating the bases, and treating them, as above prescribed, with alcohol or ether. One pound of bark rarely yields more than 2 drams of the bases. One pound of red bark aflforded, to Pelletier and Caventou, 74 grains of cinchonina, and 107 grains of quinina. » & «» Quinina is composed of 7576 carbon, 7-52 hydrogen, 811 azote, and 8-61 oxygen. 1 he salts of quinina are distinguished by their strong taste of Peruvian bark, and if crystallized by their pearly lustre. Most of them are soluble in water, and some also in ether and alcohol The soluble salts are precipitated by the oxalic, gallic, and tartaric acids, and by the ^Its of these acids. Infusion of nutgalls also precipitates them. The sulphate of quinina is the only object of manufacturing operations. Upon the brownish viscid mass obtained in any of the above processes for obtaining quinina. pour very dilute sulphuric acid in sufficient quantity to produce saturation. The solution must be then treated with animal charcoal, filtered, evaporated, allowed to cor.l, when ik deposits crystals. 1000 parts of bark afford, upon an average, 12 parts of sulphate. The sulphate of cmchonina, which is formed at the same time, remains dissolved in the mother waters. The neutral sulphate of quinina occurs in small transparent right prismatic needles. By spontaneous evaporation of their solution, larger crystals may be procured. They contain 24| per cent, of water ; and, therefore, melt when exposed to heat. They dis- solve in 11 parts of water at ordinary temperatures ; are much more soluble in hot spirit of wine, somewhat dilute, than in cold ; and are nearly insoluble in anhydrous alcohoL If they be well dried, they possess the property of becoming luminous when heated a little above the boiling point of water, especially when they are rubbed. The sulphate is, in this case, charged with vitreous electricity. This is the sub-sulphate of some chemists. There is a sub-sulphate, but it is applied to no use. The effloresced sulphate, called by some bisulphate, is preferred for medical practice. The extensive sale and high price of sulphate of quinina. have given rise to many modes of adulteration. It has been mixed with boracic acid, margaric acid, sugar, sugar of manna, gypsum. d still will shortly begin to crystallize in aZ"r of eS t ii, . '" **"', '"'' ">' 'J'"™'''"' yet n.ore definitively Setected by emfjovb ' insi.-H f ?^ "■"? "' quinidine may be previously saturated with quinidiL? bf Xh me^,s Jl oJX"''""'? ^■""'- '""^ "*« the qumine must remain undissolved^ It is mrUcularlv r„^- '»;"■'.«'■"« contained in fast experiment to observe, after the shaking CheJ an h»?T %'" r/»™i"g *i. Wl^be^dissolved on the addition of proportionatel^l": X willfcL^lne^IlT',^ infl^r^'trth^^rSn'o^a'^Srl-stsltTolit^^^^^ "^="*'' -"•• *"■• >»- >« thesuspected sal, When, if present. It^iuttlt^^^^^^^^^^^^ -it tfm^;7hrk^{wr/rttre t sz.y:? '^'"'"'' "» ^'- ^-'-"^ ^-"v- io point of c^l^ur as the usual artli; of c^^me™.'''""'"* "J""'>"«'». but not so wlit. I RAILWAY TRAIN BREAK. 537 I* You are aware that the whiter salt is brought to its snow white hue by the agency of animal charcoal, the action of sulphuric acid therefore on the lime and lime salts of the charcoal, forming sulphate of lime, is likely to be present in the white kind, unless very carefully prepared. This hospital sulphate runs no chance of such impurities, as the publislied process, when patented, will show. " The price at which it is introduced is perhaps of no moment to you, but it may be interesting to you to know that it will cost consumers about 20 per cent, less than the white kind. Independently, therefore, of its purity, I expect this great saving will not be the least of its recommendations. " The bark is boiled in a solution of caustic soda. This extracts the colouring matter and gum of the bark : it is pressed, washed with cold water, and again boiled with cau8> tic potash — again pressed, washed, and again pressed. The bark is now free of all colouring, and hence obviating the use of animal charcoal, unless the sulphate is required to be quite white — in which case I use pure animal charcoal " The pressed bark is now boiled in acid and water, and this for the first time dissolves the quina. This is precipitated by soda, and thus the pure quina is formed. On treating with acid, sulph., the hospital sulphate of quinine crystallizes at once. You now therefore see by this sketch that no impurity can exist, and* the action of the caustic soda on the bark sufficiently bleaches the quina without the aid of charcoal. The treatn^nt of the soda liquor is rather a troublesome operation, but all of which will ap- pear in the patent." — Extract of a letter. I have found Mr. Herring's hospital sulphate of quinine to be a good article, cont^n- ing within a few per cents, as much base as the whitest in the market. QUINTESSENCE. The alchemists understood by this term, now no longer in scientific use, the solution in alcohol of the principles which this menstruum can extract from aromatic plants or flowers, by digestion, during some days, in the sun, a stove, or upon a sand-bath slightly warmed. A quintessence, therefore, corresponds to the alco- holic tincture or essence (not essential oil) of the present day. See Perfumery. R. RAILWAY TRAIN BREAK. Patent break for railway trains, designed to obviate the serious defects of the common railway break. The first advantage which it presents is an improvement as to the permanent way, which is effected by the use of the long shoe, by having 18 inches of clearing surface upon the rails; it will slide over the soft and bad places hitherto made worse by the application of the ordinary break, the wheels having only about one inch of surface. The ends of the rails will not be jumped up, or flattened by the wheels coming in contact with them, which is now the case, as the wheels, resting upon the shoe, will, in fact, press such irregularities down. • llie second advantage is that in the locomotive department, the wheels' tires are always preserved perfectly circular, and the shoe, by bearing up the wheel when the br^ak is applied, prevents the flat places being formed, and also torsion upon the axles. The wheels, whether of wood or iron, are saved from being strained, and the tires, rivets, bolts, Ac. are not liable to get loose, an evil which is caused by their becoming heated. The carriage frame is also saved from being racked and twisted, as the patent break is suspended from the axle only. This will cause a great saving in the repair of break carriages. By the adoption of this break a power is gained, when applied to 2 wheels only, fully equal to the usual breaks applied to 6, a feature of no slight importance in cases of danger. This power in retarding a train is also always the same, which is not the case with the common break. The different weights with which the carriages are loaded are continually altering the position of the blocks, which varies the number of turns of the screw necessary to apply the ordinary break ; while in wet, greasy weather, it is almost impossible to skid the wheels. The patent break can be applied in less time and with 2 or 3 turns only of the screw, whereas 6 or 7 turns are required with that hitherto in use. It is also free from the usual unpleasant noise, smell, and sensation from friction. Lastly, considerable saving is effected both in the amount of stock required and in the wear and tear of railway apparatus, — Montgomery s patent. The necessity for the introduction of an improved railway break is universally admitted by all engineers and practical men. The breaks in common use are very injurious, both with regard to the duratulity of the wheels and rails. Timber blocks of poplar It 1 i I 1 i '< i 638 RAZORS. wood are made to bear hard upon the peripheries of the wheels, so as to stop their revolution. The result is the grinding of many flat places on the tire of the wheels and the abrasion of the rails, occasioning frequent renewal. RAISINS, are grapes allowed to ripen and dry upon the vine. The best come from the south of Europe, as from Roquevaire in Provence, Calabria, Spain and Por- tugal. Fine raisins are also imported from Smyrna, Damascus, and Egypt. Sweet fleshy grapes are selected for maturing into raisins, and such as grow upon the sunny elopes of hills sheltered from the north winds. The bunches are pruned, and the vine is stripped of its leaves, when the fruit has become ripe; the sun then beaming full upon the grapes completes their saccharification, and expels the superfluous water. Tlie raisins are plucked, cleansed, and dipped for a few seconds in a boiling lye of wood ashes and quicklime, at 12 or 13 degrees of Beaum6's areometer. The wrinkled fruit is lastly drained, dried and exposed in the sun upon hurdles of basket-work during 14 or 15 days. The finest raisins are those of the sun, so called ; being the plumpest bunches, which are left to ripen fully upon the vine, after their stalks have been half cut through. The amount of raisins imported for home consumption was m the year 1850, 218,982 cwts.; in 1851, 208,801 cwts. ; duty received, 1850, 172,260/.; 1851, 164.401/. RAM HYDRAULIC. Originally invented by Montgolfier, in France, and patented by him in 1797. This machine, which is self-acting, is composed of an air vessel and 3 valves, 2* for the water and 1 for keeping up the supply of air. Upon pressing down the valve in the conducting tube, which opens downwards, the water escapes from it, until this momentum is sufficient to overcome the weight, when the valve immediately rises and closes the aperture. The water, having then no other outlet than the inner valve, rushes through it by its general force, compressing the air in the air vessel until equilibrium takes place, when the air reacts by its expansive force, closing the inner valve, which retains the wajter above it, and driving it up the ascending tube. By this reaction the water is forced back along the conducting pipe, producing a partial vacuum beneath the outer valve, which immediately falls by its own weight. The water thus escapes until it has acquired sufficient force to close this, when the action proceeds as before. It is best adapted for raising moderate quantities of water, as for household or farming pur- poses. RAPE-SEED, imported for home consumption in 1850, 107,029 qrs. ; in 1851, 82,394 qrs. See Oils, unctuous. RASP, MECHANICAL, is the name given by the French to an important ma- chine much used for mashing beet-roots. See Sugar. RASPS AND FILES. File-making is a manufacture which is still in a great measure confined to Sheffield. It is remarkable that hitherto no machine has been con- structed capable of producing files which rival those cut by the human hand. Machine- made files have not the " bite " which hand-cut files have : this is accounted for by the peculiar facilities of the human wrist to accommodate itself to the particular angle suitable to produce the proper " cut" *' Small files are made out of the best cast steel; those of a larger size from ordinary steel ; flat files are forged on an ordinary study. Other forms on bolsters, with the intlentature corresponding to the shape required being thereon impressed, a chisel wider than the blank to be cut is used as the only instrument to form the teeth : it is moved by the hand with the greatest nicety. After cutting and previous to hardening, the file is immersed in some adhesive substance, such as ale- grounds, in which salt has been dissolved ; this protects the teeth from the direct action of the fire; it is then immersed perpendicularly in water; cleansed by finishing. RATAFIA, is the generic name, in France, of liqueurs compounded with alcohol, sugar, and the odoriferous or flavouring principles of vegetables. Bruised cherries with their stones are infused in spirit of wine to make the ratafia of Grenoble de Teysskre. The liquor being boiled and filtered, is flavoured, when cold, with spirit of noyeau, made by distilling water off the bruised bitter kernels of apricots, and mixing it with alcohoL Syrup of bay laurel and galango are also added. See Liqueurs. RAZORS. 151. Elliot, J. Towiihead Street, Sheffield — Manufacturer. Pattern razors manufactured of the best steel, exhibited for temper, design and workmanship. Frame back razor, ground exceedingly thin and cannot require to be again ground, thus retaining a fine and durable edge, and increasing greatly the ease of shaving. The gold, silver, steel, german-silver or brass backs, form an elegant contrast to the blade, and enhance the beauty of appearance, as well as afford more opportunity for originality of design and skill in execution. Two workmen are always engaged in razor-making. The rod of steel of which they are made is about half an inch in breadth, and of sufficient thickness to form the back. The stake upon which they are forged is rounded on both sides of the tops, which is instrumental in thinning the edge, and much facilitates the operation of grinding. The blades are then hardened and tempered in the ordinary way, with the exception that RED LIQUOR. 639 they are placed on their back on an iron plate, and the moment they assume a straw colour of a deep shade they are removed. The grinding follows, on a stone revolving in water ; then glazing on a wooden disc. The fine polish is given by a wooden wheel, having its circumference covered with buff leather, which is covered with crocus. The ornamentation of the blade by etching with acid and gilding, if such is required, is the last process. REALGAR, Red Orpiment {Arsenic rouge sulpkure, Fr. ; Rothes schwe/elarsenik. Germ.) This ore occurs in primitive mountains, associated sometimes with native arsenic under the form ot veins, efflorescences, very rarely crystalline ; as also in volcanic districts; for example, at Solfaterra near Naples ; or sublimed in the shape of stalactites, in the rents and craters of Etna, Vesuvius, and other volcanoes. Its spec. grav. varies from 3-3 to 3*6. It has a fine scarlet colour in mass, but orange red in powder, whereby it is distinguishable from cinnabar. It is soft, sectile, readily scratched by' the* nail; its fracture is vitreous and conchoidal. It volatilizes easily before the blowpipe, emitting the garlic smell of arsenic, along with that of burning sulphur. It consists of arsenic 10, sulphur 30 in 100 parts. It is employed sometimes as a pigment. Factitious orpiment IS made by distilling in an earthen retort a mixture of sulphur and arsenic, of orpiment and sulphur, or of arsenious acid, sulphur and charcoal. It has not the rich colour of the native pigment, and is much more poisonous ; since, like factitious orpiment, it always contains more or less arsenious acid. RECTIFICATION, is a second distillation of alcoholic liquors, to free them from whatever impurities may have passed over in the first. RED LIQUOR, is a crude acetate of alumina, employed in calico-printing, and pre- pared from pyrolignous acid ; which see, and Calico Printing. At first sight it would appear that alumina is the intermediate fixing agent. The pyrolignite of alumina, by its easy decomposition into acetic acid and alumina, would be the one preferred ; but practice has shown that a sulpho-acetate of alumina gives the best results, and which is composed as follows : — + SO3, -f 2 C4 H, O,, and prepared by mixing together 453 lbs. of ammoniacal alum. 379 lbs. of acetate of lead, or 315 lbs. of pyrolignite of lead. 1182 lbs. of water. AlaO, or, 383 lbs. of sulphate of alumina. 379 lbs. of acetate of lead, or 315 lbs. of pyrolignite of lead. 1132 lbs. of water. or, or. 463 lbs. of alum, and a quantity of solution of pyrolignite of lime, amounting to 158 IKq. 383 lbs. of sulphate of alumina, with the same amount of pyrolignite of lime. These substances are well stiired together for several hours, complete double decom- position ensues, sulphate of lead is deposited, and sulpho-acetate of alumina remains in solution with one equivalent of sulphate of ammonia, proceeding from the ammoniacal alum employed, as only two equivalents of sulphuric acid are removed from the four which alum contains But as sulphate of ammonia is of no use in the process of mordanting cloth, and as it may be considered as increasing the price of the articles to the manufacturer, a very intelligent firm had the good idea of replacing ammoniacal alum by sulphate of alumina, thus not only rendering the liquor cheaper, but their liquor marks the same strength as that of other manufacturers, — namely, sp. gr. 1 085, or 17 Twaddle. The red mordant D of this firm contains a larger amount of useful agents under the same bulk of fluid. The following analyses clearly show this point : (see next page)— From these results it is easy to perceive that the composition of red liquors varies a great deal m ]JIanchester, and that it is of importance to our extensive calico-printing firms to inouire more than they at present do into the composition of their red mor- dants. By doing so we have no doubt they will arrive at two ends,— viz., account better than they do for the superiority of some prints over others, and discover why certain persons always believe the peculiar red mordant they employ the best, and if results do not come up, attribute failures to the madder, «fec I may mention here a fraud or two which has been discovered in the pyrolignite of iron, or black Uquor, employed by calico printers and dyers for obtaining black erev 8 Z 2 '& ». . — ^ III i i I , , I- ■: . ' 640 REED. OompoHtion of Four MordanU per Gallon. 8alw(«Deet. Alumina - • Sulphuric acid Acetic acid • Aminoaia and water Formnln. ALs O3 8O3 QC. Hs 03 +NH3 8O3 UO. Mordant A. irrains. leso-o 1642-5 •674-1 oz. 8 6 1 1 18 20 807 936 Mordant B. ffraiiis. 1 830-0 2800-0 3670-0 ■9100 oz. 4 6 8 3 gr*- 1« 178 70 36 Fom»n'a. ALiO:.Q803 C4 HsOa + NHsSOs HO. Mordant C. uns. IS39-0 SOI 7-0 1281-7 •6531 oz. 2 1 gn. 865 395 40< 915 Formula, Ala O3 + 8O3 QC« H3O3. Mordant D. gmint, «!«4-4 16616 3679-9 oz. irr*. 4 416 3 333 8 179 mar^n, chocolate, ;^ ' ^^^ '^'-^^ '^ -^^P^-^ ^-'^e Holland reed, being ._J_jth part of 40 inches; the third is i th of 37 inches, and is adapted foi the now almost universal construction of Scotch reeds; and the fourth, being ^-th of ute"mea%u^e"''^^^^^^ ^''"'^ ""'"o^T^V Every thread appearing In thesVr'espec live measures of course represents 200 threads, or J 00 splits in the standnnl S'Vven"tfter \h?clS^ ^' T '^'^'^ '"'^^ '^ ^^'^''^'^^ ^^^ cons!SeUTe"'pr^ iound oT dvfwork Bv .^V""^t'"^^^^ '^P'^^'^ wettins^s, either at the bleach ng. ground oi (l>e.work. By counting the other way, the proportion which the woof bear, to the warp is also known and this forms the chief use of the slass to the maTfacl^re^ o? theTeTd:"^' ^'''^''' """''' °^ ^^°°^ ""'' P^^"^«"^^y ^^^"^"^^«d with the exaclmei^" REFINING OF GOLD AND SILVER. 541 Comparative Table of 37-inch reeds, being the standard used throughout Europe, for linens, with the Lancashire and Cheshire reeds, and the foreign reeds used for holland and cambric. Scotch. Lancashire. Cheshire. Dutch holland. French cambric. 600 20 34 550 653 700 24 38 650 761 800 26 44 740 870 900 30 50 832 979 1000 34 54 925 1089 1100 36 60 1014 1197 2200 40 64 1110 1300 1300 42 70 1202 1414 1400 46 76 1295 1464 1500 50 80 1387 1602 1600 52 86 1480 1752 1700 56 92 1571 1820 1800 58 96 1665 1958 1900 62 104 1757 2067 2000 66 110 1850 2176 In the above table, the 37-inch is placed first. It is called Scotch, net because it cither originated or is exclusively used in that country. It is the general linen reed of all Europe ; but in Scotland it has also been adopted as the regulator of her cotton manuo factures, REFINING OF GOLD AND SILVER; called also Parting. (JJinage d'argent. Depart, Ft. ; Scheidung in die quart. Germ.) For several uses in the arts, these pre- cious metals are required in an absolutely pure state, in which alone they possess their malleability and peculiar properties in the most eminent degree. Thus, for example, neither gold nor silver leaf can be made of the requisite fineness, if the metals contain the smallest portion of copper alloy. Till within these ten or twelve years, the parting of silver from gold ^yas effected everywhere by nitric acid; it is still done so in all the establishments of this country, except the Royal Mint ; and in the small refining-houses abroad. The following appaiatus may be advantageously employed in this operation. It will serve the double purpose of manufacturing nitric acid of the utmost purity, and of separating silver from gold by its means. 1. On procuring mine acid for parting.-'^ is a platinum retort or alembic ; b is Us capital, terminating above in a tubulure, to which a kneed tube of platinum, about 2 feet long, is adapted; c is the tubulure of the retort, for supplying acid diinng the process, and for inspecting its progress. It is furnished with a lid ground air-tight, which may be secured in its place by a weight, c is a stoneware pipe, about two inches diameter, and several feet long, according to the locality in which the operation is to be carried on. It is made in lengths fitted to one another, and secured at the joints with loam-lute. The one bend "of this earthenware hard salt-glazed pipe is adapted to receive the platinum tube, and the other bend is inserted into a tubu- lure in the top of the stoneware drum/. The (.pening /, /, in the middle oC the lop of /, is 542 REFINING OF GOLD AND SILVER. REFINING OF GOLD AND SILVER. 543 t- ■ f for inspecting the progress of the condensation of acid; and the third tubulure tenni nates in a prolonged pipe *, i, consisting of several pieces, each of which enters from above conically into the one below. The joinings of the upper pieces need not be tightjy luted, as it is desirable that some atmospherical oxygen should enter, to convert the relatively light nitrous gas into nitrous or nitric acid vapor, which when supplied with moisture will condense and fall down in a liquid state. To supply this moisture in the most diflusivc form, the upright stoneware pipes t, t, /, /, (at least 3 inches diameter, and 12 feet high), should be obstructed partially with flint nodules, or with siiicious pebbles; and water should be allowed to trickle upon the top pebble from a cistern placed above. Care must be taken to let the water drop so slowly as merely to preserve the pebbles in a state of humidity. A is a stopcock, of glass or stoneware, for drawing off the acid from the cis- tern/, k is a section of a small air-furnace, covered in at top with an iron ring, on which the flat iron ring of the platinum frame rests. g, g, is a tub in which the stoneware cistern stands, surrounded with water, kept con- stantly as cold as possible by passing a stream through it ; the spring water entering by a pipe that dips near to the bottom, and the hot water escajung at the upper edge. With the above apparatus, the manufacture of pure niiric acid is comparatively easy and economical. Into the alembic a, 100 pounds (or thereby) of pure nitre, coarsely bruised if the crystals be large, are to be put ; the capital is then to be adapted, and the platinum tube (the only moveable one) luted into its place. Twenty pounds of strong sulphuric acid are now to be introduced by the tubulure c, and then its lid must be put on. No heat must yet be applied to the alembic. In about an hour, another ten pounds of acid may be poured in, and so every hour, till 60 pounds of acid have been added. A few hours after the affusion of the last portion of acid, a slight fire may be kindled in the furnace k. By judicious regulation of the heat, the whole acid may be drawn off in 24 hours ; its final expulsion being aided by the dexterous introduction of a quart or two of boiling water, in small successive portions, by the tubulure c, whose lid must be instantly shut after every inspersion. The most convenient strength of acid for the parting process, is when its specific gravity is about 1-320, or when a vessel that contains 16 ounces of pure water, will contain 21 1 of the aquafortis. To this strength it should be brought very ex- actly by the aid of a hydrometer. Its purity is easily ascertained by letting fall into it a few drops of solution of silver; and if no perceptible milkiness ensues, it may be accounted good. Should a white cloud appear, a few particles of silver may be introduced, to separate whatever muriatic acid may be present, in the form of chloride of silver. Though a minute quantity of sulphuric acid should exist in the nitric, it will be of no consequence in the operation of parting. 2. On parting by the nitric acid, called by the Mexicans, " II apartado/'— The principle on which this process is founded, is the fact of silver being soluble in nitric acid, while gold is insoluble in that menstruum. If the proportion of gold to that of silver be greater than one to two, then the particles of the former metal so protect or envelop those of the latter, that the nitric acid, even at a boiling heat, remains quite inactive on the alloy. II is indispensable, therefore, that the weight of the silver be at least double that of the gold. 100 pounds of silver take 38 pounds of nitric acid, of specific gravity 1-320, for oxydize. ment, and 111 for solution of the oxyde ; being together 149 ; but the refiner often con- sumes, in acid of the above strength, more than double the weight of silver, which shows great waste, owing to the imperfect means of condensation employed for recovering the vapors of the boiling and very volatile acid. By the apparatus above delineated, the 38 pounds of acid expended in oxydizing the silver, become nitrous gas in the first place, and are afterwards reconverted in a great measure into nitric acid by absorption of atmospherical oxygen ; so that not one fifth need be lost, under good management. As the acid must be boiled on the granulated garble, or alloy, to etiect the solution of the silver, by proper arrangements the vapors may be entirely con- densed, and nearly the whole acid be recovered, except the 111 parts indispensable to con- stitute nitrate of silver. Hence, with economical management, 120 pounds of such acid may be assigned as adequate to dissolve 100 of silver associated with 50 of gold. It must here be particularly observed, that 100 pounds of copper require 130 pounds of the above acid for oxydizement ; and 390 for solution of the oxyde ; being 520 pounds in whole, of which less than | part could be recovered by the above apparatus. It is there- fore manifest that it is desirable to employ silver pretty well freed from copper by a pre- vious process ; and always, if practicable, a silver containing some gold. These data being assumed as the bases of the parting operation, 60 pounds of gold and silver alloy or garble finely granulated, contain ins: not less than 40 pounds of silver, are to be introduced into the ten-gallon alembic of platinum, fig. 931, and 80 pounds of nitric acid, of 1-320, is to be poured over the alloy ; a quantity which will measure 6 gallont Imperial. As for the bulk of the alloy, it is considerably less than half a gallon. Abun dait<;e of space therefore remains in the alembic for effervescence and eballition, provided the fire be rightly tempered. Bv the extent of stoneware conducting pipe e, which should not be less than 40 feet, by the cfimensions and coldness of the cistern/, and by the regenerating influence of the ver- cical aerial pipe filled with moist pebbles i, i, it is clear, that out of the 80 pounds of ni- tric acid, specific gravity 1-320, introduced at first, from 20 to 30 will be recovered. Whenever the effervescence and disengagement of nitrous red fumes no longer appear on opening the orifice c, the fire must be removed, and the vessel may be cooled by the application of moist cloths. The alembic may be then disengaged from the platinum tube, and lifted out of its seat. Its liquid contents must be cautiously decanted off, through the orifice c, into a tub nearly filled with soft water. On the heavy pulverulent gold which remains in the vessel, some more acid should be boiled, to carry off any residuary silver. This metallic powder, after being well washed with water, is to be dried, fused along with a little nitre or borax, and cast into ingots. Plates of copper being immersed in the nitric solution contained in wooden or stone- ware cisterns, will throw metallic silver down, while a solution of nitrate of copper, called blue water, will float above. The pasty silver precipitate is to be freed from the nitrate of copper, first, by washing with soft water, and next, by strong hydraulic pressure in cast iron cylinders. The condensed mass, when now melted in a crucible along with a little nitre and borax, is fine silver. The above apparatus has the further advantage of enabling the operator to recover a great portion of his nitric acid, by evaporating the blue water to a state approaching to dryness, with the orifices at c, and at the top of the capital, open. In the progress of this evaporation, nothing but aqueous vapor escapes. Whenever the whole liquid is dissipated, the pipe d is to be re-adjusted, and the lid applied closely to c. The heat bein;; now continued, and gradually increased, the whole nitric acid will be expelled from the copper oxyde, which will remain in a black mass at the bottom of the alembic. The contrivance for letting water trickle upon the pebbles, must be carefully kept in play, otherwise much of the evolved acid would be dissipated in nitrous fumes. With due attention to the regenerative plan, a great part of the acid may be recovered, at no expense but that of a little fuel. The black oxyde of copper thus obtained, is an economical form of employing thai metal for the production of the sulphate ; 100 pounds of it, with 122| of sulphuric acid diluted with water, produce 312$ pounds of crystallized sulphate of copper. A leaden boiler is best adapted for that operation. 100 pounds of silver are precipitable from its solution in nitric acid, by 29 of copper. If more be needed, it is a proof that a wasteful excess of acid has existed in the solution. In parting by nitric acid, the gold generally retains a little silver ; as is proved by the cloud of chloride of silver which it affords, at the end of some hours, when dissolved in aqua regia. And on the other hand, the silver retains a little gold. These facts indr.ced M. Dize, when he was inspector of the French mint, to adopt some other pro- cess, wnich would give more accurate analytical results ; and after numerous experi- ments, he ascertained that sulphuric acid presented great advantages in this point of view, since with it he succeeded in detecting, in silver, quantities of gold which had eluded the other plan of parting. The suggestion of M. Dize has been since univer- sally adopted in France. M. Costell, about nine or ten years ago, erected in Pomeroy- street. Old Kent-road, a laboratory upon the French plan, for parting by sulphurie acid ; but he was not successful in his enterprise ; and since he relinquished the business, Mr. Matheson introduced the same system into our Royal Mint, under the management of M. Costell's French operatives. In the Parisian refineries, gold, to the amount of one thousandth part of the weight, has been extracted from all the silver which had been previously parted by the nitric acid process ; being 3500 francs in value upon every thou- sand kilogrammes of silver. I shall give first a general outline of the method of parting by sulphuric acid, and then describe its details as I have lately seen them executed upon a magnificent scale in an establishment near Paris. The most suitable alloy for refining gold, by the sulphuric acid process, is the compound of gold, silver, and copper, having a standard quality, by the cupel, of from 900 to 950 milliemes, and containing one fifth of its weight of gold. The best proportions of the three metals are the following :— silver, 725 ; gold, 200 ; copper, 75 ; = 1000. It has been found that alloys which contain more copper, aflibrd solutions that hold some anhydrous sulphate of that metal in solution, which prevents the gold from being readily separated ; and that alloys containing more gold, are not acted on easily by the sulphuric acid. The refiner ought, therefore, when at all convenient, to reduce the alloys that he has to treat to the above-stated proportions. He may effect this purpose either by fusing the coarser alloys with nitre in a crucible, or by adding finer alloy, or even fine silver, or finally, by subjecting the coarser alloys to a previous cupellation with lead on 544 REFINING OF GOLD AND SILVER. I I It I [| I! : 'W.i ,:f • • i t.f^l Tl\ ^ ^""^ *''' ^u'^^' ]'""'''"' '^^'''^ contains Jead and other easily ox> iizable metals besides copper, the refiner uugnt always to avoid treating mem oy siJ phuric acid ; and should separate, first of all, these foreign metals by the agency of nitre if they exist m minute quantity; but if in larger, he should have Tecours? to the cuDeL be refined'.'"''^' '^'"^''' ^ ^'"'"^ ^'""^ '^' ^"^^^'""^ preparation of the aUoytc nf^l^..^ •""^.^^^^.^^''^l^'^^P^'''"'^^'^ P""^''P^^ P*"«^^» refiners are in the halit ^^InW^r"^/*""'^ '^^\^r^^^ °^ '"^P^""^ ^"^' *^ ""'^^^ ^^ «^^«i" * clear solution of sulphate of silver, which does not loo suddenly concrete on eooline, so as to ob^ruct its discharge from the alembic by decantation. A small increase in the quantity of copper! calls for a considerable increase in the quantitv of acid. ^ copper, Generally speaking, one half of the sulphuric acid strictly required for convertine the silver and copper into sulphates, is decomposed into sulphurous acid, which is lost to the manufacturer, unless he has recourse to the agency of nitrous acid. _ The process for silver containing but little gold, consists of five different opera- 1. Upon several furnaces, one foot in diameter, egg-shaped alembics of platinum are mounted, into each of which are put 3 kilogrammes (8 lbs. troy) of the granulated •liver, containing a few grains of gold per pound, and 6 kilogrammes of concentrated sulphuric acid. The alembics are covered with conical capitals, ending in bent tubes Which conduct the acid vapors into lead pipes of condensation; and the furnaces are erected under a proper hood. As the cold acid is inoperative, it must be set a boilin-. at which temperature it gives up one atom of its oxygen to the metal, and is transforme^d into sulphurous acid, which escapes in a gaseous state. Some of the undecomposed sul- phuric acid immediately combines with the oxyde into a sulphate, which subsides, in the state of a crystalline powder, to the bottom of the vessel. The solution goes on vi-or- ously, with a copious disengagement of sulphurous acid gas, only during the two or three first hours ; after which it proceeds slowly, and is not completed till after a digestion of nearly twelve hours more. During the ebullition a considerable quantity of sulphuric acid vapor escapes along with the sulphurous acid gas; the former of which is readily condensed in a large leaden receiver immersed in a cistern of cold water, if need be It has been proposed to condense the sulphurous acid, by leading it over extensive surfaces of Iime-pap, as in the coal-gas purifiers. 2. When the whole silver has been converted into sulphate, this is to be emptied out ?i 7^!ir,"u i"*°. ^^!5^ contamedin a round-bottomed receiver lined with lead, and nflu • /k r^''^'^ ""^u^^ '^^"^^"'I "^^'^^ ^'^^ ^^' *° 20° Baume. The small portion ol gold m the form of a brown powder, which remains undissolved, having been allowed to settle to the bottom, the supernatant solution of silver is to be decanted carefully off into a leaden cistern, and the powder being repeatedly edulcorated with ^ater the wash- ings are to be added to it. The silver is now to be precipitated by plunging plates of copper m the solution, and the magma which falls is to be well washed, and freed from the residuary particles of sulphate of copper by powerful compression. 3. The silver, precipitated and dried as above described, is melted in a crucible and east into an ingot. * ., ^V'T^^ ^^^^ PO^i ' fi ji; ■ fnpernaiant sulphate of copper is then run off into a cistern, upon a somewhat lower ierel, where it is left to settle and become clear. The precipitate of silver, called by the English, water-silver, and by the French, chaus i*argent, is drained, then strongly squeezed in a square box of cast-iron, by the action ol a hydraulic press ; in which 60 pounds of silver are operated upon at once. The silver lumps are dried, melted in black lead crucibles, in a furnace built near the lilver end of the room, where the superintendent sits in his bureaus, closet enclosed by glazed casements, like a green-house. The whole course of the operations is so planned, that they are made to commence near the centre with the mixed metals, and progressive- ly approach towards the office end of the apartment as the parting processes advance. Here the raw material, after being granulated and weighed, was given out, and here the pure gold and silver are finally eliminated in a separate state. In the other half of the hall, the solutions of sulphate of copper are evaporated in large shallow leaden pans, placed over a range of furnaces ; from which, at the proper degree of concentration, they are run off by syphons into crystallizing pans of the same metal. From the mother-waters, duly evaporated, a second crop of crystals is obtained j and also a third, the last being anhydrous, from the great affinity for water possessed by the strong sulphuric acid with which they are now surrounded. The acid m this way parts with almost the whole of the cupreous oxyde, and is then transferred into a large alembic of platinum (value 1000/.), to be rendered fit, by re-conceniration, for acting upon fresh portions of granulated silver. The capital of that alembic is connected with a leaden worm, which traverses an oblong vessel, through which a stream of cola The crystallized sulphate of copper fetched, two years ago, 301. a ton. It is almost all soM to the grocers in the towns of the agricultural districts of France. In the above es- tablishment of M. Poizat, silver to the value of 10,000/. can be operated upon daily. There is a steam engine of 6-horse power placed in a small glazed chamber at one side of the parting hall, which serves to work all his leaden pumps for lifting the dilute sul- phuric acid and acidulous solutions of copper into their appropriate cisterns of concen- tration, as also to grind his old crucibles, and drive his amalgamation mill, consisting of a pair of vertical round-edged wheels, working upon one shaft, in a groove formed round a central hemisphere— of cast-iron. After the mercury has dissolved out of the ground crucibles all the particles of silver which it can find, the residuary earthy matter is sold to the sweep-washers. The floor of the hall around the alembics, pots, and cisterns, is covered with an iron grating, made of bars having one of their angles uppermost, to act as scrapers upon the shoes of the operatives. The dust collects in a vacant space left beneath the gratin?, whence it is taken to the amalgamation mill. The processes are so well arranged and conducted by M. Poizat, that he can execute as much business m bis establishment with 10 workmen as is elsewhere done with from 40 to 50 ; and with less than 3 grains of gold, in one Paris pound or 7561 grains of silver, he can defray the whole expenses of the parting or refining. Since 26 parts of copper afford 100 of the crystallized sulphate, the tenth of coppei present in the dollars, and most foreign coins, will yield nearly four times its weight of blue vitriol; a subsidiary product of considerable value to the refiner. The works of M. Poizat are so judiciously fitted up as to be quite salubrious, and have not those «« very mischievous effects upon the trachea," which Mr. Matheson slates as being common in his refinery works in the Roya. Mint.* But, in fact, as refining by sulphuric acid is always a nuisance to a neighborhood, it is not suffered in the Monnaii Royale of Paris ; but is best and most economically performed by private enterprise and fair competition, which is impossible in London, on account of the anomalous privilege, worth at least 2000/. a year, possessed by Mr. Malheson, who works most extensively for private profit on a public plant, fitted up with a lofty chimney, platinum vessels to the value of 3000/., and other apparatus, at the cost of the government. His charge to the crown for refining gold per lb. troy, is 6«. Qd. ; that of the refiners in London, who are obliged, for fear of prosecution, to employ the more expensive, but more condensable, Bitric acid, is only 4s. That of the Parisian refiners is regulated as follows. For the dealers in the precious metals : — For gold bullion containing silver, and more than ^«-00_ of gold, 6 fr. 12 c. per kilo- gramme, = 2 fr. 29 c. per lb. troy. For silver bullion, containing from ^^1^ to ^y>Oy of gold (called dares)^ 3 fr. 27 c per kilogramme, = 1 fr. 22 c. per lb. troy. For the Monnaie, the charges are — For gold refined by sulphuric acid, when alloyed with copper only, from -f-^^ ^o TT^JHTi C fr. per kilogramme, = 1 fr. 86 c. per lb. troy. For gold alloyed with copper and silver, whatever be the quantity of silver, 5 fr. 75 c* per kilogramme, = 2 fr. 12 c. per lb. troy. * Report of Committee of House of Commona on the Mint, in 1837, p. 91. REFRIGERATION OF WORTS. 547 There arc ab»ut ten bullion refiners by sulphuric acid in the environs of Paris; two of whom,M. Poizat St. Andre, and M. Chauviere, are by far the most considerable: the former working about 300 kilogrammes ( = 804 lbs. troy) daUy,and the latter about two Uiiras 01 that quantity. In former times, when competition was open in Ix>ndon, Messrs. Browne and Bnnde were wont to treat 6 cwts. of sUver, or 9 cwts. of gold alloy, daily, for several months m succession. J» J» The result of /rce/rarfe in refining bullion at Paris is, that the silver bars imported into London from South America, &c., are mostly sent off to Paris to be stripped of the few grams of gold which they may contain, and are then brought back to be sold here. * «?I!**"^ *^. ^""^^ *" """^ ^*"® ^^' ""^ s^*^^'*» P«^y ^^^ "^finers there for taking them out. What a disgrace is thus brought upon our manufacturing industry and skill, by the monopoly charges m refining and assaying granted to two individuals in our Roval Mint. Mr. Bingley's charges for assaying at the Royal Mint in London, are— For an assay of gold, 4s. ; for a parting assay of gold and silver, 6*. ; for a sUver assay 2». brf.— charges which absorb the profits of many a transaction. The charges at the Royal Mint of Paris, for assays made under the following distin- |aished chemical savants— D&rcct, Directeur i Breant, VerijicateHT: Chevillot and Pelouze. iLssayturs; are — y^^y^^ For an assay of gold, or dorc (a parting assay), 3 francs. Ttr n r" ^"T "~, — 0- 80 c. = 8(i. English. M, Cxay Lussac is the assayer 01 the Bureau de Garantie at the Monnaie RoLole, an office which corresponds 10 the Goldsmiths' Hall at London. The silver assays in all the official establishments of Europe, except the two in London, are made by the humid method, and are free from those errors and blunders which daily annoy and despoil the British bullion merchant, who is compelled by the Mint and Bank of England to buy and sellby the c«/)c//a/i(wi assay of Mr. Bindley. See Assay and Silver. REFRIGERATION OF WORTS, &c. In August, 1826, Mr. Yandall obtained a patent *«v^*i ua hP mft ^^% ^?^' ^201 represent different forms in which the apparatus is proposed to ^rvi T? T ^'? ^''''^ ^'^^ V^^^^K^s ; the third, channels running in convolute J.nJfh J^T r*^5 f ^''*^^' *''^ ^^*^^ ^°^*" ^'^P^^^ity in thickness, but of great Jftg. 1202 is the section of a portion of the apparatus shown at figs, 1199 & 1200 upon Sue nSt r?J'rl. '' ? "'^^^ ^y connecting three sheets of copper or any othe thhi S2 tollic plates together, leavi \g parallel spaces between each plate for the passage of ^e fluids, represented by the biack lines. passage oi me ribI\TnoTt?on.' oVmirjrf b^ occasionally introducing between the plates thin straps, S^P rhrnnTthf? •? ' ^ "^^'^^ ?^*"' ^^"^^ thin channels are produced, and throuS !.!^^ and Zl. • K^' ""'^ *"^^"^^ ^° ^^ P^s^^d' ^^^ cold Uquor running in one dirls- Uon, and the hot m the reverse direction. ""cv- Supposing that the passages for the fluids are each one eighth of an inch thick then the entire ength for the run of the fluid should be about 80 feet, the breadth of the ai^ ^Tn ?r/ "y;?^,'^<^c«"*i"^to the quantity of fluid intenTeitoVe pas^J^^roug^^^^^^ shouirbe exienied to I'^Xt """h '""^^ I ^"^^^ «^ ^"^ ^"^^ thicCthen theirWglh Should be extended to 160 feet; and any other dimensions in similar proportions : but a Hrhntrpr nl" T ^"!?''5*! ^"^^'^^« Patentee considei^ wouldTob ectiin^^^^^^^ t on^ thanrp inid/«L^'r^^ 't' ^' ^^'^'^ ^''^ recommended, is under thi considera- i^'fmm a hildtnT /^r^"" ^«>"?\the apparatus by some degree of hydrostatic pres- tTli^Th. nf ivi n ^^^^^fU-^^t^above ; but if the fluids flow without pressure, then me lengths of the passages need not be quite so great In the apparatus constructed as shown in perspective at fig, 1199, and further .1 : If ; ■T- i ; I 348 REFRIGERATION OF WORTS. REFRIGERATION OF WORITS. 549 seveloped by the section, Jig» 1202, cold water is to be introduced at the funnel », whence it passes down the pipe b, and through a long slit or opening in the side of the pipe, into the passage c, c (see fig, 1202), between the plates, where it flows in a horizontal direction through the channel towards the discharge-pipe d. When such a quantity of cold water has passed through the funnel a, as shall have filled the channel c, c, up to the level of the top of the apparatus, the cock e being shut, L'len the hot wort or liquor intended to be cooled, may be introduced at the funnel /, and which, descending in the pipe gj passes in a similar manner to the former, through a long slit or opening in the side of the pipe g, into the extended passage r.,^ (see^g. 1202), and from thence proceeds horizontally into the discharge- pipe i. _ The two cocks c and k, being now opened, the wort or other liquor is drawn off, or otherwise conducted away through the cock fc, and the water through e. If the apertures of the two cocks e and k are equal, and the channels equal also, it follows that the same quantity of wort, &c., will flow through the channel A, h, A, in a given time, as of water through the channel c, c; and by the hot fluid passing through the apertures in contact with the side of the channel which contains the cold fluid, the heat becomes abstracted from the former, and communicated to the latter ; and as the hot fluid enters the apparatus at that part which is in immediate contact with the part where the cooling fluid is discharged, and the cold fluid enters the apparatus at that part where the wort is discharged, the consequence is, that the wort or other hot liquor becomes cooled down towards its exit-pipe nearly to the temperature of cold water ; and the temperature of the water, at the reverse end of the apparatus, be- comes raised nearly to that of the boiling wort. It only remains to observe, that by partially closing either of the exit-cocks, the quan- tity of heat abstracted from one fluid, and communicated to the other, may be regulated ; for instance, if the cock e of the water-passage be partially closed, so as to diminish the quantity of cold water passed through the apparatus, the wort or other hot fluid conducted through the other passages will be discharged at a higher temperature, which in some cases will be desirable, when the refrigerated liquor is to be fermented. J'tg. 1200 exhibits an apparatus precisely similar to the foregoing, but diflferent in its position ; for instance, the zigzag channels are made in obliquely descending planes. a is the funnel for the hot liquor, whence it descends through the pipe d into the channel c, c (see yig. 1202), and ultimately is discharged through the pipe b, at the cock e. The cold water being introduced into the funnel /, and passing down the pipe t, enters the zigzag channel h, h, and, rising throi^h the apparatus, runs ofl* by the pipe g, and is discharged at the cock below. The passages of this apparatus for heating and cooling fluids, may be bent into various contorted figures ; one form found particularly convenient under some applications, is that represented at fig. 1201, which is contained in a cylindrical case. The passages here run in convolute curves, the one winding in a spiral to the centre, the other receding from the centre. The wort or other hot liquor intended to be cooled, is to be introduced at the funnel a, and passing down the pipe b, is delivered into the open passage c, which winds round to the central chamber d, and is thence discharged through the pipe e, at the cock /. The cold water enters the apparatus at the funnel f, and proceeding down the pipe h, enters the 1200 closed channel t, and after traversing round through the apparatus, is in like manner discharged through the pipe fe, at the cock I. Or the hot liquor may be passed through the closed channel, and the cold through the open one ; or these chambers may be both of them open at top, and ihe ap- paratus covered by a lid when at work, the principal design of which is to aflford the convenience of cleaning them more readily than could be done if they were closed ; or they may be both closed. A similar ingenious apparatus for cool- ing brewer's worts, or wash for distillers, and also for condensing spirits, in place of the ordinary worm tub, is called by the inventor, Mr. Wheeler, an Archi- medes condenser, or refrigerator, the pe- culiar novelty of which consists in form- ing the chambers for the passage of the fluids in spiral channels, winding round a central tube, through which spiral channels the hot and cold fluids are to be passed in opposite directions. Fig, 1203 represents the external appearance of the refrigerator, enclosed in a cylin- drical case ; fig, 1204, the same, one half of the case being removed to show the form 1202 of the apparatus within ; and fig. 1205, a section cut through the middle of the appa- ratus perpendicularly, for the purpose of displaying the internal figure of the spiral channels. The apparatus is proposed to be made of sheet copper, tinned on its surface, and is formed by cutting circular pieces of thin cop- „ per, or segments of circles, and connecting ihem together by rivets, solder, or by any other convenient means, as coppersmiths usu- ally do ; these circular pieces of copper being united to one another, in the way of a spiral or screw, form the chambers through which the fluids are to pass within, in an ascending or descending inclined plane. 1203 1204 Inyig*. 1204 , is supported by the two bearers r, made fast to the cross-beam e. There is in the lowest part of the hollow ring at bot- tom, a screw plug, which may be opened when it is desired to discharge the whole con- tents, and to wash it with a stream of water. REGULUS is a term introduced by the alchemists, now nearly obsolete. It means literally a little king, and refers to the metallic slate as one of royalty, compared with the native earthy condition. Antimony is the only metal now known by the name of r^ulus. RENNET. The gastric juice of the stomach of the sucking calf, which, being extracted by infusion immediately after the death of the animal, serves to curdle milk. As the juice passes rapidly into putrefaction, the stomach must be salteil after the outer skin has been scraped off, and all the fat and useless membranes carefully removed. It is only the inner coat which is to be preserved after it is freed from any curd or other extraneous matter in the stomach. The serum left in it should be pressed out with a cloth, and is then to be replaced in the stomach with a large quantity of the best salt. The skins, or veils as they are called, are next put into a pan and covered with a saturated solution of salt and soaked for some hours ; but there should be no more brine than covers the veils. They are afterwards hung up to dry, a piece of wood being put crosswise into each to stretch them out They should be perfectlv iSried and look like parchment. In this state they may be kept in a dry place for any length of time, and are always ready for use. Pieces of veil are cut off and soaked for some hours in wey or water, and the whole is added to the warm milk for curdling it, its strength having been first tested on a small c[uantity. By the rapidity with which it curdles and the form of the flakes, a judgment is formed of its strength and the quantity required for the whole milk. RESINS, (^e«ine«, Fr. ; JIarze, Germ.) ; are proximate principles found in most vege- tables, and in almost every part of them ; but the c«ily resins w^hich merit a particular description, are those which occur naturally in such (quantities as to be easily collected or extracted. They are obtained chiefly in two ways, either by spontaneous exudation from the plants, or by extraction by heat and alcohol. In the first case, the discharge of resin in the liquid state is sometimes promoted by artificial incisions made in summer through the bark into the wood of the tree. Resins possess the following general properties: — They are soluble in alcohol, insoluble in water, and melt by the application of heat, but do not volatilize without partial decom- position. They have rarely a crystalline structure, but, like gums, they seldom affect anv peculiar form. They are almost all translucid, not often colourless, but generally brown, occasionally red or green. Any remarkable taste or smell, which they sometimes possess, may be ascribed to some foreign matter, commonly an essential oil Their specific gravity varies from 092 to 1-2. Their consistence is also very variable. The greater part are hard, with a vitreous fracture, and so brittle as to be readily pulverized in the cold- Some of them are soft, a circumstance probably dependent upon the presence of a heterogeneous substance. The hard resins do not conduct electricity, and they become negatively electrical by friction. When heated they melt more or less easily into a thick viscid liquid, and concrete, on cooling, into a smooth shining mass, of a vitreous fracture, which occasionally flies off into pieces, like Prince Rupert's drops ; especially, after being quickly cooled, and scratched with a sharp point. They take fire by contact of an ignited body, and bum with a bright flame, and the diffusion of much sooty smoke. When distilled by themselves in close vessels, they afford carbonic acid and carburetted gases, erapyreumatic oil of a less disagreeable smell than that emitted by other such oils, a little acidulous water, and a very little shining charcoal See Rosin Gas. Resins are insoluble in water, but dissolve in considerable quantities in alcoliol, both hot and cold. This solution reddens tincture of litmus, but not syrup of violets ; it is decomposed by water, and a milkiness ensues, out of which the particles of the resin gradually agglomerate. In this state it contains water, so as to be soft, and easily kneaded between the fingers; but it becomes hard and brittle again when freed by fusion from the water. The resins dissolve in ether and the volatile oils, and, with tlie aid of heat, combine with the unctuous oils. They may be combined bv fusion with eulphur, and with a little phosphorus. Chlorine water bleaches several coloured resins, if they be diffused in a milky state through water. The carburet of sulphur dissolves them. Resins are little acted upon by acids, except by the nitric, which converts them into artificial tan. They combine readily with the alkalis and alkaline earths, and form what were formerly reckoned soaps; but the resins are not truly saponified; they rather represent the acid constitution themselves, and, as such, saturate the salifi- able bases. Every resin is a natural mixture of several other resins, as is the case also with oils; one prmciple being soluble in cold alcohol, another in hot, a third in ether, a fourth in oil of turpentine, a fifth in naphtha, Ac. Tlie soft resins, which retain a certain portion of volatile oil, constitute what are called balsams. Certain other balsams contain bensoic acid. The solid resins are, amber, anime, benzoin, colophony (common rosin), copal, dammar a, dragon's blood, elemi, guaia/:, lac, resin oi jalap, ladanum, tnastic, tandarack, ftorax, takamahae. An ingenious memoir upon the resins of dammar, copal, and anime, has lately been published by M. Guibourt, aa eminent French pharmacien, from which the following extracts may be found interesting. The hard copal of India and Africa, especially Madagascar, is the product of the Hymenaa verrucosa ; it is transparent and vitreous within, whatever may be its appear- ance outside; nearly colourless, or of a tawny yellow; without taste or smell in the cold, and almost as liard as amber, which it much resembles, but from which it may be distinguished, 1st, by its melting and kindling at a candle-flame, and running down in drops, while amber burns and swells up without flowing; 2dly, this hard copal or anim6 when blown out and still hot, exhales a smell like balsam copaiva or capivi ; while amber exhales an unpleasant bituminous odour; 3dly, when moistened bv alcohol of 85 per cent., copal becomes sticky, and shows after drying a gkzed opaque surfkcei, 662 RESINS. ^ii ii 'If while amber is not affected by alcohol ; 4thly, the copal affords no succinic add, as amber does, on distillation. When the pulverised copal is digested in cold alcohol of 0-830, it leaves a considerable residuum, at first pulverulent, but which swells afterwards, and forms a slightly coherent mass. When this powder is treated with boiling alcohol it assumes the consistence of a thick gluten, like crumbs of bread, but which does not stick to the fingers Thus treated, it affords, ^ ' ^ RHODIUM. 553 Resin soluble in cold alcohol Resin dissolved in boiling alcohol - Resin insoluble in both 81-42 4-00 65-71 100-83 The small excess is due to the adhesion of some of the menstruum to the resins. Ether, boiling hot, dissolves 39-17 per cent, of copal. Essence (spirits) of turpentine does not dissolve any of the copal, but it penetrates and combines with it at a heat of 212° Fahr. The property of swelling, becoming viscid and elastic, which Berzelius assigns to copal belongs not to it, but to the American resin of courbaril, or the occidental anime - and the prooerty of dissolving entirely in ether belongs to the aromatic dammar, a friable and tender resin. 2. Resin of courbaril of Rio Janeiro, the English gum-anira6, and the semi-hard copal of the French. It is characterised by forming, in alcohol, a bulky, tenacious elastic mass. It occurs m rounded tears, has a very pale glassy aspect, transparent within, covered with a thin white powder, which becomes glutinous with alcohol Another variety is soft, and dissolves, for the most part, in alcolK>l • and a third* resembles the oriental copal so much as to indicate that they may both be produced from the same tree. 100 parts of the oriental and the occidental anime yield respec- tively the following residua : — J f Oriental Occidental "With alcohol. 65-71 43-53 With ether. 60-83 27-50 With essence. Ill 75-76 The hard and soft copals possess the remarkable property in common of becoming soluble in alcohol, after being oxygenated in the air. 8. Dammar puti, or dammar batu.— This resin, soft at first, becomes eventually like amber, and as hard. It is little soluble in alcohol and ether, but more so ia essence ef turpentine. 4. Aromatic dammar. — This resin occurs in large orbicular masses. It is pretty soluble in alcohol Only small samples have hitherto been obtained. Of 100 parts, 3 are inso- luble in alcohol, none in ether, and 93 in essence of turpentine. M. Guibourt' thinks that this resin comes from the Molucca isles. Its ready solubility in alcohol, and great hard- ness, render it valuable for varnish-making. 6. Slightly aromatic dammar leaves, after alcohol, 37 per cent. ; and after ether 17 per cent. ; and after essence 87 per cent. ' 6. Tender and friable dammar selan. — Tliis resin occurs in considerable quantity in commerce (at Paris). It is in round or oblong tears, vitreous, nearly colourless and trans- parent within, dull whitish on the surfaces. It exhales an agreeable odour of olibanuin or mastic, when it is heated. It crackles with the heat of the hand, like roll-sulphur. It becomes fluid in boiling water, but brittle when cooled again. It sparkles and burns at the flame of a candle ; but this being the effect of a volatile oil the combustion soon ceases. Resin soluble in cold alcohol Resin insoluble in boiling alcohol 75-28 20-86 It dissolves readily and completely in cold essence of turpentine, and forms a good varmsh. M. Guibourt refers the origin of this resin to the Dammara selanica of Rumphius. Of the preceding resins, 100 parts have left respectively Hard copal, or anime Tender copal Dammar puti Dammar aromatic Dammar austral Dammar slightly aromatic Dammar friable Alcohol of 0-830. - 65-71 - 43-53 3-0 - 43-33 - 37-00 - 20-86 Insoluble In Ether. 60-83 27-50 36-66 17-00 2-00 Essence. Ill 76-76 93 80 87 RESIN, KAURI or COWDEE, is a new and very peculiar substance, recently im- ported in considerable quantities from New Zealand, which promises to be useful in the arts. It oozes from the trunk of a noble tree called Dammara australis, or Pinus kauri, which rises sometimes to the height of 90 feet without a branch, with a diameter of 12 feet, and furnishes a log of heart timber of 11 feet. The resin, which is called Cowdee gum by the importers, is brought to us in pieces varying in size from that of a nutmeg to a block of 2 or 3 cwts. The color varies from milk-white to amber, or even deep brown ; some pieces are transparent and colorless. In hardness it is intermediate between copal and resin. The white milky pieces are somewhat fragrant, like elemi. Specific gravity, 1*04 to 1*06. It is very inflammable, burns all away with a clear bright flame, but does not drop. When cautiously fused, it concretes into a transparent hard tough mass, like shellac. It affords a fine varnish with alcohol, being harder and less colored than mastic, while it is as soluble, and may be had probably at one tenth of the price. A solution in alcohol, mixed with one fourth of its bulk of a solution in oil of turpentine, forms an excellent varnish, which dries quickly, is quite colorless, clear and hard. It is insoluble kn pyro-acetic (pyroxilic ?) spirit. Combined with shellac and turpentine, it forms a good sealine-wax. REVERBERATORY FURNACE ; see Copper, Iron, and Soda. RETORT. For producing coal gas, there are many modifications, varying in dimension and shape with the caprice of the constructor, and in many cases without any definite idea of the principle to be aimed at. They may be divided into three general classes : 1st. The circular retort, from twelve to twenty inches in diameter, and from six to nine feet in length. This retort is used in Manchester and some other places, in gene- ral for the distillation of cannel, or Scotch parrot coal. It answers for the distillation of a coal which retains its form in lumps, and is advantageous only from the facility with which its position is changed, when partially destroyed by the action of fire on the under side. 2d. The small or London d retort, so called in consequence of its having first been nsed by the chartered tnmpany in London, being still in use at their works, and re- commended by their engineer. This retort is 12 inches broad on the base, 11 inches high, and 7 feet long, carbonizing one and a half to two bushels at a charge. 3rd. The York D retort, (so called in consequence of its having been introduced by Mr. Outhit, of York,) and the modifications of it, among which I should include the elliptic retort, as having the same general purpose in view. The difference between the London and York D retorts, consists only in an extension of surface upon which the coal i8 spread. See Gas-light. Clay retorts for gas works. Mr. Joseph Cowan, of Newcastle, has much improved the quality of clay retorts, by mixing in their composition with Newcastle fire clay, or any other good fire clay of the coal measures, sawdust, pulverised coke, or carbon obtained from the inside of gas iron retorts, « pn>d«ced ^^^^^^^ chemical furnace is incapable of fusing il ; and the on y way of giving it cohes ve soad- itvTs to calcine the sulphuret or arseniuret of rhodium man ^P^" vessel at a white hlit till all the sulphur or arsenic be expelled. A bntton may thus be obtained, some- what pon«iy having the color and lustre of silver. Accordmg to ^ oUaston the Toec fie gral ty of rhodium is 1 1. It is insoluble by itself m any acid ; but when an mirofof ft S certain metals, as platinum, copper, bismuth, or lead is trea ed with iaua reoia The rhodium dissolves along with the other metals; but when alloyed with S or lUver it wUl not dissolve along with them. It may, however, be rendered very Sluble by miiinlit in the state of a fine powder with chloride of potassium or sodium Tad heatinnhe mixture to a dulUred heat, in a stream of chlorine gas. t thus forms a Oriole sal very soluble in water. The solutions of rhodium are of a beautiful rose color »wn.!. A nILe In the dry wav, it dissolves by heat in bisulphate of potassa ; and l^eZ^s sTlphuroul\ctd%;7in"theactof solution!. There are '- oxY-^^^^^^^ Rhodium combines with almost all the metals; and, m small quantity, 'n^Ued with stee , ShasTeen supposed to improve the hardness, closeness, and toughness of this metal, rl^hief use atTesent is fo? making the inalterable nibs of the so-named rhodium pens. Ri RRO^ MANUFACTURE, is a modification of Weaving, which see. , , ^ , R CE ?f Cifrolina analyzed by Braconnot, was found to be composed of starch 85^7 of eluteu t^'of^r^^^^^ uncrystallizable sugar 0-29 of a colourless rancid fet iL su^et laf ofVegeW fib;e 4-8. of 'salts with potash and lime bases 04, and 6-0 of water. RIVETTING-MACfflNE. 555 Year. I Imported. 1850 1861 1860 1851 Entered for Home ConsumptioD. cwts. 785,451 745,736 qrs. 37,150 31,481 Rice. cwte. 435,961 399,170 nice in the husk. qre. 86,430 28,291 Duty received. £ 12,789 11,013 £ 1821 1414 Rice Paver as it is called, on which the Chinese and Hindoos paint flowers so prettily. Rtee raper, ^ " »\*'*";, ' . . ,, ^rtocarpus incisifoha of naturalists. ^ "mcTSEVNING^ V^^^^^^^^^ machines halTbe^en contrived for effecting tliis purpose RlCb ULiiiiAiNiiMij. V itriuua jn»^ vf^itril WiUon in 1826. may be regarded of »hich the following secured ^X P»*«"' *" Mr ^eWa ^^^^^^ 8 b, ^j^^ „_^.^.^^_ husks or impurities may adhere to them. A hopper is set above to ever ever iiui>iv3 ui iw.|yu. »-.>- j _ and conduct it down into the cleansing cy mder. ^roiecting so as to reach verv ''t^e?=\rsr;inc«nea in the figure ^^^Z^::^ ^^^ it may le placed also "P"?'"' »' •'"I\^""'*\f"f„"^^id „S' wh»« '>'» """''" framework. The central shaft should be put '" '»P'f '°f ^Sli^d by that ac'tion, U receives a slow motion m the opposite ^''f ''»»•. „^?/;X*?„J„*"tSu,^ (shoot), and i. ^^^^X^. ' Thf ^:J^' ™:;- b^'arW e'l If hanTor by any' other' eonve- ""'SKnlists chiefly of starch, ->erefore «nnpt by itse^^^ fa used in the cotton factnr.es to '"^^^^^/^.''SfitLto fibres and plates, ':t^ t^^ulrlt^' CUtrorr^i':t^Z^^^ relmb^g those of mother-of-pearl. When a decoction of rice is fermented and distilled, it affords the sort of ardent spirit called arrack in the East Indies. RIFLE. See Fire Arms. RINSING MACHINE, is one of those ingenious automatic contrivances for economizing labour, and securing uniformity of action, now so common in the factories of Lancashire. Fig. 1208 is a longitudinal middle section of an approved mechanism for rinsing pieces of calico dyed with spirit or fancy colours, and which require more delicate treatment than is compatible with hand-washing, a e f b is a wooden cistern, about 21 feet long, 4 feet high at one end, 2 feet at the other, and of the ordinary width of calico cloth. It is divided transversely into a series of equal compartments by partitions, de- creasing in height from the upper to the lower end, the top of each of them, however, being an inch at least under the top of the enclosing side at its line of junction. Above the highest end of the trough, a pair of squeezing rollers ia mounted at b ; the lower one having a pulley upon the end of its shaft, for turning it, by- means of a band from one of the driving-shafts of the factory ; and the upper one is pressed down upon it by weightetl levers acting on the ends of its axis. The roller above the second highest partition has also a pair of squeezing rollers, with a weighted lever a The pieces of cloth, stitched endwise, being laid upon a plat- form to the right hand of the cistern, are intro- duced over the roller a, passed down under the roller beneath it, and so up and down in a ser- pent-like path, from the lowest compartment of the cistern to the uppermost, being drawn through the series by the traction of the rotatory roller at b. While the long web is thus pro- ceeding upwards from a to b, a stream of pure water is made to flow along in the opposite di- rection from b to A, running over the top of each partition in a thin sheet. By this contrivance, the goods which enter at a, having much loose colour upon their surfiice, impregnate the water strongly, but as they advance they continually get cleaner by the immersion and pressure of the successive rollers, being exposed to purer water, till at last they reach the limpid stream, and are discharged at b, perfectly bright. The rinsing operation may be modified by varying the quan- tity of water admitted, the speed with which the pieces are drawn through the cells, or the pres- sure upon the series of top rollers. RIVETTING MACHINE of Fairbairn. The invention of the rivetting machine originated in a turn-out of the boiler-makers in the employ of that great engineer about fifteen years ago. On that occasion an attempt was made to rivet two plates together by compres-oing the red-hot rivet in the ordinary punching-press. The success of this experiment immediately led to the construction of the original machine, in which the moveable die was forced upon the rivet by a powerful lever acted upon by a cam. A short experience proved the original machine inadequate to the numerous require- ments of the boiler-maker's trade, and the present form was therefore adopted about twelve years since. The large stem, a, is made of malleable iron, and, having an iron strap b b screwed round the base, it renders the whole perfectly safe in case of the dies coming in contact vith a cold rivet, or any other hard substance, during the process. Its construction also allows the workman to rivet angle iron along the edges, and to finish the corners of boilers, tanks, and cisterns; and the stem being now made 4 feet 6 inches high, it renders the maclime more extensive in its application, and allows of its rivetting the fire- box of a locomotive boiler or any other work within the given depth. In addition to these parts, it has a broad moving slide, c, in which are three dies corre- sponding with others in the wrought iron stem. By using the centre die. everv descrip- tion of flat and circular work can be riveted, and by selecting those on the sides, it wiU rivet the corners, and thus complete vessels of almost every shape. This machine is ia 566 RIVETTING-MACHINE. I v: II t 1 M ' 1^1 ^ m iii ft portable form, and can be moved off raUB with care to suit the article suspended from %heTntroduction of the knee-joint gives to the dies a variable motion and ca^f.^^J;? greatest force to be exerted at a proper time, viz. at the closing of the jomt and finii^hinsr of the head of the rivet. , , . • * „*-„«,«„« in other respects the machine operates as before, effecting by an almost mstantaneouB wessure what is performed in the ordinary mode by a long series of impacts. Ihe machine fiLes in the firmest manner, and completes eight rivets of f inch dianieter in • mbu e wUh the attendance of two men and Uy« to the plates and rivets ; ^ereas the ftver^; work that can be done by two riveters, with one « holder on" and a boy is 40* ROPE-MAKING. 557 inch rivets per hour ; the quantity done in two cases being in the proportion of 40 to 480, or as 1 to 12, exclusive of the saving of one man's labour. The cylinder of an ordinary locomotive engine boiler 8 feet 6 inches long and 3 feet diameter can be riveted and the plates fitted completely by the machine in 4 hours ; whilst to execute the same work by hand would require with an extra man twenty hours. The work produced by the machine is likewise of a superior kind to that made in the ordinary manner ; the rivets being found stronger, and the boilers more free from leakage, and more perfect in every respect. Tlie riveting is done without noise, and thus is almost entirely removed the constant deafening clamour of the boiler-maker's hammer. ROCKETS. M. de Montgery, captain of a frigate in the French service, has written a Traite mr les Fmees de Gtierre, in which he discusses the merits of the Congreve rockets, and describes methods of imitating them. As the subject of military projectiles is foreign to this Dictionary, I refer my readers to the above work, which is commended by the editor of the D'ctionnaire Technologique. ROLLING-MILL. See Iron, Mint, and Plated Manufacture. ROOFING, ASPHALTK Patent asphalte roofing felt, particulariy applicable for warm climates. It is a non-conductor. It is portable, being packed in rolls, and not being liable to damage in carriage, it effects a saving of half the timber usually required. It can be easily applied by any unpractised person. From its lightness, weighing only about 42 lbs. to the square of 100 feet, the cost of cartage is small. The felt can be laid on from gable to gable, or across the roof from eaves to eavea It is essential that it should be stretched tight and smooth, overlapping full one inch at the joinings, and closely nailed through the overlap, with twopenny fine clout nails, (heated in a shovel and thrown when hot into grease to prevent rust,) about 1^ inches apart, but copper nails are preferable. The whole roof must have a good coating of coal-tar and lime, (about two gallons of the former to six pounds of the latter), well boiled together, kept constantly stirring while boiling, and put on hot with a common tar mop, and while it is soft some coarse sharp sand may be sifted over it The coating must be renewed every fourth or fifth year, or more or less frequently according to the climate. The gutters should be made of two folds, one over the other, cemented together with the boiling mixture. ROPE-MAKING. The fibres of hemp which compose a rope, seldom exceed in length three feet and a half, at an average. They must, therefore, be twined together so as to unite them into one ; and this union is effected by the mutual circumtorsion of the two fibres. If the compression thereby produced be too great, the strength of the fibres at the points where they join will be diminished ; so that it becomes a matter of great consequence to give them only such a degree of twist as is essential to their union. The first part of the process of rope-making by hand, is that of spinning the yarns or threads, which is done in a manner analogous to that of ordinary spinning. The spin- ner carries a bundle of dressed hemp round his waist ; the two ends of the bundle being assembled in front. Having drawn out a proper number of fibres with his hand, he twists them with his fingers, and fixing this twisted part to the hook of a whirl, which is driven by a wheel put in motion by an assistant, he walks backwards down the rope> walk, the twisted part always serving to draw out more fibres from the bundle round his waist, as in the flax-spinning wheel. The spinner takes care that these fibres are equably supplied, and that they always enter the twisted parts by their ends, and never by their middle. As soon as he has reached the termination of the walk, a second spin- ner takes the yarn off the whirl, and gives it to another person to put upon a reel, while he himself attaches his own hemp to the whirl hook, and proceeds down the walk. "When the person at the reel begins to turn, the first spinner, who has completed his yarn, holdg it firmly at the end, and advances slowly up the walk, while the reel is turning, keeping it equally tight all the way, till he reaches the reel, where he waits till the second spinner takes his yarn off the whirl hook, and joins it to the end of that of the first spinner, in order that it may follow it on the reel. The next part of the process previous to tarring, is that of warping the yarns, or stretching them all to one length, which is about 200 fathoms in full-length rope-grounds, and also in putting a slight turn or twist into them. The third process in rope-making, is the tarring of the yarn. Sometimes the yams are made to wind off one reel, and, having passed through a vessel of hot tar, are wound upon another, the superfluous tar being removed by causing the yarn to pass through a hole surrounded with spongy oakum ; but the ordinary method is to tar it in skeins or hanks, which are drawn by a capstan with a uniform motion through the lar-keltle. In this process, great care must be taken that the tar is boiling neither too fast nor too slow. Yarn for cables requires more tar than for hawser-laid ropes ; and for standing and run- ning rigging, it requires to be merely well covered. Tarred cordage has been found to be weaker than what is untarred, when it is new ; but the tarred rope is not so easily injured by immersion in water. *IJ ti 'M II: 558 ROPE-MAKING. EOPE-MAKING. The last part of the process of rope-making, is to lay the cordage. For this pnrpora two or more yarns are attached at one end to a hook. The hook is then turned the con- trary way from the twist of the individual yarn, and thus forms what is called a strand. Three strands, sometimes four, besides a central one, are then stretched at length, and attached at one end to three contiguous but separate hooks, but at the other end to a single hook ; and the process of combining them together, which is eflected by turning the single hook in a direction contrary to that of the other three, consists in so regulating the progress of the twists of the strands round their common axis, that the three strands receive separately at their opposite ends just as much twist as is taken out of them by their twisting the contrary way, in the process of combination. Large ropes are distinguished into two main classes, the cable-laid and hawser-laid. The former are composed of nine strands, namely, three great strands, each of these con- sisting of three smaller secondary strands, which are individually formed with an equal number of primitive yarns. A cable-laid rope eight inches in circumference, is made up of 333 yarns or threads, equally divided among the nine secondary strands. A hawser-latd rope consists of only three strands, each composed of a number of primitive yarns, propor- tioned to the size of the rope ; for example, if it be eight inches in circumference, it may have 414 yarns, equally divided among three strands. Thirty fathoms of yarn are reck- oned equivalent in length to eighteen fathoms of rope cable-laid, and to twenty fathoms hawser-laid. Ropes of from one inch to two inches and a half in circumference are usu- ally hawser-laid ; of from three to ten inches, are either hawser or cable-laid j but when more than ten inches, they are always cable-laid. Every hand-spinner in the dock-yard is required to spin, out of the best hemp, six threads, each 160 fathoms long, for a quarter of a day's work. A hawl of yam, in the warping process, contains 336 threads. The following are Captain Huddarl's improved principles of the fope manufacture ^^ 1. To keep the yarns separate from each other, and to draw them from bobbins revolT- ing upon skewers, so as to maintain the twist while the strand or primarj' cord is forming. 2. To pass them through a register, which divides them by circular shells of holes; the number in each concave shell being conformable to the distance from the centre of the strand, and the angle which the yarns make with a line parallel to it, and which gives them a proper position to enter. 3. To employ a tube for compressing the strand, and preserving the cylindrical figure of its surface. 4. To use a gauge for determining the angle which the yarns in the outside shell make with a line parallel to the centre of the strand, when registering ; because accord- ing to the angle made by the yams in this shell, the relative lengths of all the yams in the strand will be determined. 5. To harden up the strand, and thereby increase the angle in the outside shell; which compensates for the stretching of the yarns, and the compression of the strands. A great many patents have been obtained, and worked with various degrees of success, for r;iaking ropes. Messrs. Cartwright, Fothergill, Curr, Chapman, fialfour, and Hud- dart, have been ttie most conspicuous inventors in this country ; but the limits of thii work preclude us doing justice to their respective merits. All the improvements in the manufacture of cordage at present in use, either in her Majesty's yards or in private rope-grounds, owe their superiority over the old method of making cordage to Captain Huddart's invention of the register plate and lube. Mr. Balfour took out a patent for the manufacture of cordage about a month before Captain Huddart; but the formation of his strand was to be accomplished by what he called a top minor (in the form of a common top, with pins to divide the yarns), which upon trial could not make cordage so good as by the common mode. On seeing Cap- tain Huddart's specification, Mr. Balfour, five years after, procured another patent, ia which he included a plate and tube, but which was not sufficiently correct, and ex- perience in the navy proved the insufficiency of the cordage. Captain Huddart'& plate and tube were then adopted in the king's yards, and he gave his assistance for the purpose. Captain Huddart then invented and took a patent for a machine, which by registering the strand at a short length from the tube, and winding it up as made, preserved a uni- formity of twist, or ans^le of formation, from end to end of the rope, which cannot be ac- complished by the method of forming the strands down the ground, where the twist ift communicated from one end to the other of an elastic body upwards of 300 yards in length. This registering-machine was constructed with such correctness, that when some were afterwards required, no alteration could be made with advantage by the most skilful and scientific mechanic of that day, Mr. Rennie. Thus the cold register was car- ried to the greatest perfection. A number of yarns cannot be put together in a cold state, without considerable vacancies, into which water may gain admission ; Captain Huddart, therefore, formed the 559 yams into a strand immediately as they came from the tar-kettle, which he was enabled to do by his registering-machine, and the result was most satisfactory. This combination of yarns was found by experiment to be 14 per cent, stronger than the cold register; it con- stituted a body of hemp and tar impervious to water, and had great advantaee over any other cordage, particularly for shrouds, as after they were settled on the masl-head, and properly set up, they had scarcely any tendency to stretch, effectually secured the mast, and enabled the ship to carry the greatest press of sail. In order more effectually to obtain correctness in the formation of cables and large cordage. Captain Huddart constmcted a laying-machine, which has carried his inventions in rope-making to the greatest perfection, and which, founded on true mathematical prin- ciples, and the most laborious calculations, is one of the noblest monuments of mechanical ability since the improvement of the steam-engine by Mr. Watt. By this machine, the strands receive that degree of twist only which is necessary, and are laid at any angle with the greatest regularity ; the pressure is regulated to give the required elasticity, and all parts of the rope are made to bear equally. In no one instance has a rope or cable thus formed been found defective in the lay, or stiff, or difficult to coil. Such a revolution in the manufacture of cordage could not be accomplished without great expense, as the works at Limehouse fully testify ; and considerable opposition necessarily arose. Captain Huddart's first invention was, however, generally adopted as soon as the patent expired ; and experience has established the great importance of his subsequent improvements. His cordage has been supplied in large quantities to her Majesty's navy, and has re- ceived the most satisfactory reports. The following description of one of the best modern machines for making ropes on Captain Huddart's plan, will gratify the intelligent reader. J'lig. 1211 exhibits a side elevation of the tackle-board and bobbin-frame at the head T of the ropcLV, and also of the carriage or rope-machine in the act of hanlin*' oat^nd twisting the strands. ^ ® i^tg.l212is a front elevation of the carriage. IVg. 1213is a yarn-guide, or board, or plate, with perforated holes for the yams to pan through before entering the nipper. ^^ Figs. 1214 and 1215 are side and front views of the nipper for pressing the rop«i. a is he frame for containing the yarn bobbins. The yarns are brought from tbe frame, and pass through a yarn-guide at b. c is a small roller, under which the rone- yarns pass ; they are then brought over the reel rf, and through another yarn-guide e after which they enter the nippers at v, and are drawn out and formed into strands by the carriage. The roller and reel may be made to traverse up and down, so as to regulati the motion of the yarns. ^ The carriage runs on a railway. /,/, is the frame of the carriage ; g, g, are the smaU wheels on which it is supported ; k, k, is an endless rope, reaching from the head to 1212 the bottom of the railway, and is driven by a steam-engine; wi, nj, IS a wheel with gubs at the back of it, over which the endless rope passes, and gives motion to the machinery- of the oarriage. «, is the ground rope for taking out the carriage, as will be afterwards described. On the shaft of wi, wi, ^e two bevel wheels 3, 3, with a shifting catch between them: these bevel wheels are loose upon the shaft, but when the catch rs put into either of them, this last then keeps motion with the slMft, while the other runs loose. One of these wheels serves to communicate the twist to the strand in drawing out ; the other gives the opposite or after turn to the rope in closing. 4, 4, is a lever for shifting the catch accordingly. 6, is a third bevel wheel, which i eceives its I'^ti I 560 ROPE-MAKING. ROPE-MAKING. Ml H ,!■' ; li! 1 ■ 1213 w^ 1214( D 1215 ! i . motion from either of the other two, and communicates the same to the two spur wheels 6, 6, by means of the shaft x. These can be shifted at pleasure ; so that by applying wheels of a greater or less number of teeth above and beneath, the twist given to the strands can be increased or diminished accordingly. The upper of these two communicates motion, by means of the shaft o, to another spur wheel 8, which working in the three pinions above, 9, 9, gives the twist to the strand hooks. The carriage is drawn out in the following manner. On the end of the shaft of m, w, is the pinion 3, which, working in the large wheel b, gives motion to the ground-rope shaft upon its axis. In the centre of this shaft is a curved pulley or drum /, round which the ground-rope takes one turn. This rope is fixed at the head and foot of the ropery ; so that when the machinery of the carriage is set a-going by the endless rope k, k, and gives motion to the ground-rope shaft, as above described, the carriage will neces- sarily move along the railway ; and the speed may be regulated either by the diameter of the circle formed by the gubs on the wheel »n, tm, or by the number of teeth in the pinion 3. At T, is a small roller, merely for preventing the ground- rope from coming up among the machinery. At the head of the railway, and under the tackle-board, is a wheel and pinion z, with a crank for tightening the ground-rope. The fixed machinery at the head, for hardening or tempering the strands, is similar to that on the carriage, with the ex- ception of the ground-rope gear, which is unnecessary. The motion is communicated by another endless rope (or short band, as it is called, to distinguish it from the other), which passes over gubs at the back of the wheel 1, 1. When the strands are drawn out by the carriage to the requisite length, the spur wheels 3, R, are put out of gear. The strands are cut at the tackle-board, and fixed to the hooks 1, 1, 1 ; after which they are hardened or tempered, being twisted at both ends. When this operation is finished, three strands are united on the large hook h, the top put in, and the rope finished in the usual w^ay. In preparing the hemp for spinning and ordinary thread or rope yarn, it is only heckled over a large keg or clearer, until the fibres are straightened and separated, so as to run freely in the spinning. In this case, the hemp is not stripped of the tow, or cropped, unless it is designed to spin beneath the usual grist, which is about 20 yarns for the strand of a three-inch strap-laid rope. The spinning is still performed by hand, being found not only to be more economical, but also to make a smoother thread, than has yet been effected by machinery. Various ways have been tried for preparing the yams for tarring. That which seems now to be most generally in use, is, to warp the yarns upon the stretch as they are spun. This is accomplished by having a wheel at the foot, as well as the head of the walk, so that the men are able to spin both up and down, and also to splice their threads at both ends. By this means, they are formed into a haul, resemb ing the warp of a common web, and a little turn is hove into the haul, to pre- serve it from getting foul in the tarring. The advantages of warpins: from the spin- ners, as above, instead of winding on winches, as formerly, are, 1st, the saving of this last operation altogether; 2dly, the complete check which the foreman has of the quantity of yarn spun in the day ; Sdly, that the quality of the work can be subjected to the minutest inspection at any time. In tarring the yarn, it is found favorable to the fairness of the strip, to allow it to pass around or under a reel or roller in the bottom of the kettle while boiling, instead of coiling the yarn in by hand. The tar is then pressed from the yarn, by means of a sliding nipper, with a lever over the upper part, and to the end of which the necessary weight is suspended. The usual proportion of tar ia ordinary ropes, is something less than a fifth. In large strap-laid ropes, which are ne- cessarily subjected to a greater press in the laying of them, the quantity of tar can scarcely exceed a sixth, without injuring the appearance of the rope when laid. For a long period, the manner of laying the yams into ropes, was by stretching the haul on the rope-ground, parting the number of yarns required for each strand, and •wisting the strands at both ends, by means of hand-hooks, or cranks. It will be obvious that this method, especially in ropes of any considerable size, is attended with serious disadvantages. The strand must always be very uneven ; but the principal dis- idvantage, and that which gave rise to the many attempts at improvement, was, that She yarns being all of the same length before being twisted, it fc^Jlowed, when the rope was finished, that while those which occupied the circumference of the strand were per- fectly tight, the centre yarns, on the other hand, as they were now greatly slackened by the operation of hardening or twisting the strands, would actually bear little or no part •>f the strain when the rope was stretched, until the foimer gave way. The method lisplayed in the preceding figures and description, is among the latest and most improved. Every yarn is given out from the bobbin frame as it is required in twist* mg the rope ; and the twist communicated in the out-going of the carriage, can be in- creased or diminished at pleasure. In order to obtain a smooth and well-filled strand, It 18 nectary also, in prmmg the yarns through the upper board, to proportion the number of centre to that of outside yams. In ordina^r sfzed ropes, the strand seems to have the fairest appearance, when the outside yarns form from fd to fths of the whole strandF' '" ^ ^"^'"^ ^""^^ ^^ ^^"^ ""^""'^^ "" drawing out and forming the 10?* ^?y'"f/a^les, torsion must be given botli behind and before the laying top. i^«. IZ1», 17, 18. represent the powerful patent apparatus employed for this purpose, j^ia 1216 :t1np;^e?e'n?JL7lT^ ^---ta. beam .. ., and bearing bobbins \!r reels round y^^^thr^rjJ2r^' . °' J"' ^'^ ^'^'^ «^ *^« '^^ee gr^ These are drawn up byTT ro^i^^f ^T^J? ^^T^' ^^^^ ^^^««" ^'^ ^«^"d. over the three guije pulWs k k T towardf^h! 1 "^'"f '*'"^''' '' '' '> ^^^^^ P«>ceed the tube o. to be wounLiSi tWbie rleTo '^li^f'"^ top m and finally pass through do not revolve about the f^p^lkrV^ a im-n?. -'^T! ^^ ^h"^'^^ ^^^^' «» h. h. its own shaft q, which is steadied hf«K^° ^/^' ^"* ^^^^ ^^^"^ revolves roimd bottom. The three ^bbins are n^aced ^If'"'^ "^^l'^ f ^' *"^ ^ <^"i^ Btep at ite JBceives a rotatory motiorupon its^iwrom Z7£X "/ ^'' ^1?^^ ^P^'*' ^^ each by the common central spur^ wheel o Th^s Li rtu '??' ^^^^^ «' ^^^^^ " driven proper degree of twist put into it inoJ^^rJr ^^.^^^^ three secondaiy cords has a suitable digree of twist ki an oppos^^^^ ^re^Tl''nJ^^:^' '^^'^^^' '' ^^'^'^^ Setting a o, G, round two pivot., the one under the nS/ ^J^ f^^olution of the frame or c%6 has thus, like the bobbins h, h, two 2vemen2 ^*^"' "^^'' ^- ^h^ '^^ that upon its axis, produced by thLaSbnTfJ^o' a^ »» common with its frame, and <«e of its ends, and the pulley e' above tscentr'^^^^^^ *^« pulley e, upon the bevel mill-gearing pf p p as alsoX nL ""^ notation. The pulley e is driven^y '¥ -g.'.//l216^hich belr^fhe"^^^^ -.in//l2li istheplaceo?= view of the bobbin h, to show the worm of p??i P""^^' "^ ^ ^- ^^>- ^217 is an end wo snail-toothed whUls, upl theTdTof the fwnTT \?^'^^' ^^'^' ^^'^^'^^ ^'^ '^^ them. The upright shafts of j,/ receive tbp1r^t•'1."'''"''^V '' ^*^^^^ «^'^« *« *««•«» re wi J, J, receive their motion from pulleys and cords near their .it, .11 i I 562 ROPE-MAKING. bottom. Instead of these puDeys, and the others k, «', bevel-T^heel geenng .haa been s^^tu^ted with advantage, not' being liable to slip, like the pulley-band mechamsny Th? axis of the great reel is made twice the length of the bobbin d, in order to allow of the latter moving from right to left, and back again alternately, in winding on thecable with uniformity as it is laid. The traverse mechanism of this part is, for the sake oi TwSiar&'oTe W obtained a patent in May, 1833, for an improve ment' adapted to the ordinary machines employed for twisting hempen yarns into strands, Wording, it is said, a simpler and more eligible mode of accomplishing that object, and also of laying the strands together than has been hitherto effected by machinerv The yarns spun from the fibres of hemp are wound upon bobbins and Jhese bobbins are mounted upon axles, and hung in the frame of the machine, as shown in the elevation, Ha. 1219, from which bobbins the several ends of yarn are passed upwaids tSroucrh slaS^^^ by the rotation of which tubes, and of the carriages in which th^ febbbs are suspended, the yarns become twisted into strands, and also the strands are laid so as to form ropes. . . x. i. ^e His improvements consist, first, in the application of three or more tubes, two of wWch are shown in iq. 1219, placed in inclined positions, so as to receive the strands Trnmedirely Xve t^^^^^ «, -, and nearly'in a line with a, the point of closing "ng the rope. B^nd b^, are opposite side views; B^ ^V'fjrt'f^r th^'tu^a section of the same. He does not claim any exclusive right of patent for the tubes themselves, but only for their fonn and angular position. ^ i oi a f n P«rh Secondly, in attaching two common flat sheaves, or pulleys, c, o, ^. 1219., to eacn ^SM&MmmmmM: of the said tubes nearly round which each strand is lapped or coiled, to prevent it from afippL ^ sW Tnthe section b^ The said sheaves or pulleys are connected by a tw^'or'nte wheel n. loose upon 6, 6. the main or upright axle ; B.|. »« \^f^^ wheel upon each tube, working into the said crown or centre wheel, and fixed upon the ^Tk> a tTothet t sp^r whed, fixed also upon each of the loose boxes ^^^^^^^^^ into a smaller wheel o, upon the axis 2, of each tube ; h, is a bevel whee faxed upon the Sme iTwith G, and woAing into another bevel wheel J, fixed upon the cross axle 3 Tf eac^tube; k, is a spur wheel attached to the same axis with^ at the opposite end ^/working into i, another spur wheel of the same size upon each of the tubes. By wheels thS" arranged and connected with the sheaves or pulleys, as above descnbed, TpeXtly equal strain or tension is put upon each strand as drawn forward over the pulley r ROPE-MAKING. 668 ^ ,^ri/' r invention consists in the introduction of change wheels if . ic, m m Jig 1219., for putting the forehard or proper twist into each strand before the rop^ is laid ; this is effected by smaU spindles on axles 4, 4, placed paraUel with the line of each tube B, Upon the lower end of each spindle the bevel wheels n, n, are attached, and driven t>y other bevel wheels o, o, fixed immediately above each press-block a, a. On the top end of each spindle or axle 4, 4, is attached one of the change wheels, working into the other change wheel fixed upon the bottom end of each of the tubes, whereby the forehard or proper twist in the strands for all sizes of ropes, is at once attained, by simply changing the sizes of those two last described wheels, which can be very readily effected, from the manner in which they are attached to the lubes b, b, and 4, 4. ' ' From the angular position of the tubes towards the centre, the strands are nearly in contact at their upper ends, where the rope is laid, immediately below which the forehard or proper twist is given to the strands. Fourthly, in the application of a press-block p, of metal, in two parts, placed directly above and close down to where the rope :'s laid at a, the inside of which is polished, and the under end is bell-mouthed ; to prevent the rope from being chafed in entering it, a sufficient grip or pressure is put upon the rope by one or two levers and weights 5, 5, acting upon the press-block, so as to adjust any t; ifling irregularity in the strand or m the laying ; the inside of which being polished, gives smoothness, and by the said levers and weights, a proper tension to Ihe rope, as it is drawn forward through the press-block. By the application of this block, ropes may be made at once properly stretched, rendering them decidedly preferable and extremely advantageous, particularly for shipping, inclined planes, mines, &c. The preceding description includes the whole of Mr. Norvell's improvements; the remaining parts of the machine, being similar to those now in use, may be briefly described as follows:— A wheel or pulley c, is fixed independently of the machine, over Which the rope passes to the drawing motion represented at the side ; d, d, is a grooved wheel, round which the rope is passed, and pressed into the groove by means of the lever and weight e, e, acting upon the binding sheaf/, to prevent the rope from slipping. After the rope leaves the said sheave, it is coiled away at pleasure, g, g, are two chan-e wheels, for varying the speed of the grooved wheel rf, rf, to answer the various sizes li ropes; A, is a spiral wheel, driven by the screw fc, fixed upon the axle Z; »n, is a band- wheel, which IS driven by a belt from the shaft of the engine, or any other communicating power ; «, w, is a friction strap and striking clutch. The axle q, is driven by two change wheels />,p; by changing the sizes of those wheels, the different speeds of the drum r/r, for any sizes of ropes, are at once effected. The additional axle «, and wheels /, t, shown in fi^, 1220, are applied occasionally for reversing the motion of the said drums, and making what is usually termed left-hand ropes; r^ fig,. 1219., 1220, show a bevelled pinion, "driving the main crown whiir« which wheel carries and gives motion to the^^drums r, e ; «, «,, is a fixed ^s^n wheel' which gives a reverse motion to the drums, as they revolve round the s^me, by me^s of the mtervemng wheels x x,x, whereby the reverse or retrograding motioi is prXed and which gives to the strands the r ght twist The various retrograding mo ioS^rtht tw St for aU sizes and descriptions of ropes, may be obtained by changing the diaLet'ers of the pinions y, y, y, on the under ends of the drum spindles ; the carriafes of the inte^ vening wheels zxx, being made to slide round the ring z, .;V, w, is tKamewo k of the machine and drawing motion; t.t.'t, are the bobbins containing the vaJr thei number is varied to correspond with the different sizes of the machine! ^ ' thrl^lT "^ 7^ ^"^y^'i' »°.«l^.^*'ion and plan, is calculated to make ropes from three to seven and one-half inches m circumference, and to an indefinite length, W Il'ri5?KT ^^^*^!^^^' to whom the art of rope-making is deeply indebted, hav- ing observed that rope yarn is considerably weakened by passing through the tar-kettle 564 ROSIN. ; Ihat tarred cordage loses ils strength progressively in cold climates, and so rapidly m hot climates as to be scarcely fit for use in three years, discovered that the deterioration was due to the reaction of the mucilage and acid of the tar. They accordingly proposed the followinsj means of amelioration. 1. Boiling it with water, in order to remove these two soluble constituents. 2. Concentrating the washed tar by heat, till it becomes pitcny, and then restoring the plasticity which it thereby loses, by the addition of Ullow, or ani- mal or expressed oils. ,. j r ^.v;^.* » In 1807, the same able engineers obtained a patent for a method of makAng a belt or flat band, of two, three, or more strands of shroud or hawser-laid rope, placea side by side, so as to form a band of any desired breadth, which may be used for hoistmg the kibbles and corves in mine-shafts, without any risk of ils losing twist by rotation. The ropes should be laid with the twist of the one strand directed to the right hand, that of the other to the left, and that of the yarns the opposite way to the strands, whereby perfect flatness is secured to the band. This parallel assemblage of strands has been found also to be stronger than when they are all twisted into one cylinder. The patentees at the same time contrived a mechanism for piercing the strands transversely, in order to brace them firmly together with twine. Flat ropes are usually formed of hawsers wiUi three strands, softly laid, each containing 33 yarns, which with four ropes, compose a cord- age four and a half inches broad, and an inch and a quarter thick, being the ordinary dl- mensions of the grooves in the whim-pulleys round which they pass. Relative Strength of Cordage, shroud laid. Size. Warm Register. 1 Cold Register. Commun Staple. Tons. Cwts. Qrs. Lbs. Tons. Cwts. Qrs. Us. Tons. Cwts. Qrt. Lhs. 3 inches bore - H - 4 — 4J - 5 — H - 6 — 6^ - 7 — n - 8 — 3 5 17 5 — 16 3 4 5 9 3 2 16 21 2 3 9 6 1 1 24 27 6 8 10 12 14 17 13 14 19 15 2 1 2 2 16 8 4 4 24 5 7 9 11 13 17 5 3 1 3 3 1 2 4 1 4 25 8 4 5 6 7 8 5 1 9 12 17 3 2 2 1 6 8 22 20 18 21 2 10 15 17 9 18 1 3 9 8 9 11 16 4 3 1 14 21 24 27 2 8 1 16 26 20 23 11 8 1 1 9 8 12 13 8 2 3 3 6 12 The above statement is the result of several hundred experiments ROPE Exhihition.-S^Qdmem of Smith's patent galvanized and ungalvanized iron and copper wire ropes used for railway inclines, various mming operations including pit guutes, suspensfon bridges, standing rigging, lightning conductors, window and conservatory sashes, fencing, and submarine telegraphs. xi „ • u* Iron wire ropes are of equal strength with a hempen rope of four times the weight, and resist the wear and tear they are subjected to in "running gear twice as long. If the surface of a wire rope be left in any part unprotected by some coating impene- trable to moisture, the internal fibres become in process of time oxidized, and unseen decay goes forward. Iron cleaned by acid, and plunged mto a bath containing melted zinc, bicomes coated with that metal, and the parts left unzmced alone rust Iron thus treated is said to be galvanized. . , - Specimens of subLrine telegraph wire rope. Round wire '«F P'-epared for use The improvement is stated to consist in preventing the wires and strands from being twisted on themselves in the process of laying them round centre cores of hemp m giving an equal tension to eacC individual wire, and in preserving the mterior surface from corrosion by saturating the cores of hemp with tar, Ac, Sample of wire strand, used for fencing, signal cord, Ac Sample of wire rope^ Wire rope for suspension bridges, and cable laid wire ropes. Wire ropes showing the mode of splicing. Patent wire ropes for submarine telegraph; lightning conductor ; copper window-sash cord and picture cord. Patent flat wire rope, and guide rope for coal pits, Ac. Rope which has been at work constantly for five years. ROSIN, or COLOPHANY {Galipot, Fr.; Fichtenharz, Germ.); is the rosm left after distilling off the volatile oil from the different species of turpenUne. Yellow rosm contains some water, which black rosin does not. See Tuopeotinb. ROSIN GAS. 565 raylof 'I'^Martin^/u ^^ZX"/"' ^''''K'f'^ ''' ^PP«"^«g««. " erected by Messrs. Aitviur wiu jnariineau, under the direction of the patentee, Profeslor Daniel F R ™jnon brown rosin of densed from the rosin v-apours in a nrerHIno: i ^^ T^^^ "^'^^ *'^« e^^euimX oil (con- pounds of the former to t^n ^ "o,7ofThe "after^T"-^ fl *'^' proportion of one hunilred air beneath serves to preserve this in a fluid If J i" k"'"^^ ^^ *^" ^*"^« ^"'^ ^^^ated aperture in the chimney, the temp ratufe of ^1'^^ ^^ * t^"^' P^^'"? ^^'^ ^^^ wire-gauze screen at / Reaches to tKoUonf oMhe t.nl™^^^^ "^"''^^ regulated. A or any impurity with which it may iL m xed from .l,ll- ' ^?^ P'^'^^"*' *^^ ^^^'^ ^osin. ITie meTted rosin Imvincr pa^ed bv t f. „/ f ?H"^ ^^^ stopcock, retort, falls on the coke' ind i^t^ pas^I Je th^Klt^' 'Tf ^' "".^ ^^P^^" ^' '"*« '^^ On arriving at the other end of the retort a wJ ^^^"^ "J^"' ^"^"^^ decomposed, the form of condensable vapour s separated ^!ff P?"^'"*" °^ ^^'^ ^'^ «^ turpentiW^ in water from a cistern aboveS the nKilnLhl! refrigerator 5. ; this is sup^ied with and « beneath the surface of the flu?d in h:"^^^^^^ TTif "^^^ *"'^ *' and the gas proceeds in a perfectly pure state hvf hi ^.^'!.««"Pjete8 the condensation ; to the floating reservoir, for use ' ^ ^^^ P'P® ^' *^ ^^^ gasometer, or rather iti i 566 RUM. SABOTIERE. 507 ftf! Hi borne in mind that the tube prevents the escape of the gas, which would otherwise pass awav from the bo»with the essential oil. Another pipe and sjphon w, n, serve to con- vev the condensed essential oil from the top cistern. BOTTEN-STONK See Tripoli. ROUGE. (Fard, Fr.) The only cosmetic which can be applied without injury to brighten a lady's complexion, is that prepared, by the following process, from safflower, {Carthamus tinctoritu.) The flowers, after being washed with pure water till it comes off colorless, are dried, pulverized, and digested with a weak solution of crystals of soda, which assumes thereby a yellow color. Into this liquor a quantity of finely carded white cotton wool is plunged, and then so much lemon juice or pure vinegar is added as to supersaturate the soda. The coloring matter is disengaged, and falls down in an im- palpable powder upon the cotton filaments. The cotton, after being washed in cold water, to remove some yellow coloring particles, is to be treated with a fresh solution of carbo- nate of soda, which takes up the red coloring matter in a state of purity. Before precipitating this pigment a second time by the acid of lemons, some soft powdered talc should be laid in the bottom of the vessel, for the purpose of absorbing the fine rouge, in proportion as it is separated from the carbonate of soda, which now holds it dissolved. The colored mixture must be finally triturated with a few drops of olive oil, in order to make it smooth and marrowy. Upon the fineness of the talc, and the proportion of the safflower precipitate which it contains, depend the beauty and value of the cosmetic. The rouge of the above second precipitation is received sometimes upon bits of fine-twisttd woollen stuff, called crepons, which ladies rub upon their cheeks. RUBY. See Lapidary. RUM, is a variety of ardent spirits, distilled in the West Indies, from the fermented skimmings of the sugar teaches, mixed with molasses, and diluted with water to the proper degree. A sugar plantation in Jamaica or Antigua, which makes 200 hogs- heads of sugar of about 16 cwts. each, requires, for the manufacture of its rum, two cop- per stills ; one of 1000 gallons for the wash, and one of 600 gallons for the low wines, with corresponding worm refrigeratories. It also requires two cisterns, one of 3000 gallons for the lees or spent wash of former distillations, called dunder (Quasi redundar, Span.), another for the skimmings of the clarifiers and teaches of the sugarhouse ; along with twelve, or more, fermenting cisterns or tuns. Lees that have been used more than three or four times, are not considered to be equally fit for exciting fermentation, when mixed with the sweets, as fresher lees. The wort is made, in Jamaica, by adding to 1000 gallons of dunder, 120 gallons of molasses, 720 gallons of skimmings ( = 120 of molasses in sweetness), and 160 gallons of water; so that there may be in the liquid nearly 12 per cent, of solid saccharum. Another proportion, often used, is 100 gallons of molasses, 200 gallons of lees, 300 gallons of skimmings, and 400 of water ; the mixture containing, therefore, 15 per cent, of sweets. These two formulae prescribe so much spent wash, according to my opinion, as would be apt to communicate an unpleasant flavor to the spirits. Both the fermenting and flavor- ing principles reside chiefly in the fresh cane juice, and in the skimmings of the clarifier ; because, after the sirup has been boiled, they are in a great measure dissipated. I have made many experiments upon fermentation and distillation from West India molasses, and always found the spirits to be perfectly exempt from any rum flavor. The fermentation goes on most uniformly and kindly m very large masses, and requires from 9 to 15 days to complete ; the difference of time depending upon the strength of the wort, the condition of its fermentable stuff, and the state of the weather. The progress of the attenuation of the wash should be examined from day to day with a hydrometer, ns 1 have described in the article Distillation. When it has reached nearly to its maxU mum, the wash should be as soon as possible transferred by pumps into the still, and worked off by a properly regulated heat ; for if allowed to stand over, it will deteriorate y acetification. Dr. Higgins's plan, of suspending a basket full of limestone in the wash tuns, to counteract the acidity, has not, I believe, been found to be of much use. It would be better to cover up the wash from the contact of atmospheric air, and to add perhaps a very little sulphite of lime to it, both of which means would tend to arrest the acetous fermentation. But one of the best precautions against the wash becoming sour, is to preserve the utmost cleanliness among all the vessels in the distillery. They should be scalded at the end of every round with boiling water and quicklime. About 115 gallons of proof rum are usually obtained from 1200 gallons of wash. The proportion which the product of rum bears to that of sugar, in very rich moist plantations, is rated, by Edwards, at 82 gallons of the former to 16 cwt. of the latter ; but the more usual ratio is 200 gallons of rum to 3 hogsheads of sugar. But this proportion will ne- cessarily vary with the value of rum and molasses in the market, since whichever fetches the most remunerating price, will be brought forward in the greatest quantity. In one considerable estate in the island of Grenada, 92 gallons of rum were made for eTery hogshead (16 cwts.) of sugar. See Still. Imported. Retained for Oonsamption. Duty received. Gallons. Gallons. £. 1860 4.194,683 2,902,212 1,100,286 1851 4,747,031 2,880,776 1,098,200 RUSSIAN LEATHER, as tanned at Kazan. The hides to be tanned may be either fresh from the animal or dry, no matter which ; they are first laid to soak for 3 days and nights in a solution of potash, to which some quicklime is added. The potash used Is made of the tree called in Russ ilim (the common elm), which sort is said to be preferable to any other, if not essential ; it is not purified, so that it is of a brown colour and of an earthy appearance : about 12 poods of this, (the pood is 86 lbs. English), and 2 poods of lime serve for 100 skins. As they have no way of ascertaining the degree of causticity of the alkali but by its effect upon the tongue, when they find it weak they let the skins lie loDgCT in the solution. When the skins are taken out of this solution they are carried to the river and left under water for a day and a night Next a vedro of dog's dung is boiled in as much water as is enough to soak 60 skins (the vedro is equal to 2696 English imperial gallons), but in the winter time, when the dung is frozen, twice that quantity is found necessary. The skins are put into this solu- tion, not while it is boiling hot, but when at the heat which the hand can bear ; in this they lie one day and one night. The skins are then sewed up so as to leave no hole ; in short, so as to be water-tight ; about one third of what the skin will contain is then filled up with the leaves and small twigs chopped together of the plant called in Russ Toloknanka (Arbutus uvaursi, some- times called bear berry), which is brought from the environs of Solikamskaga, and the skin is then filled up with water. The skins thus filled are laid one on the other in a large trough, and heavy stones upon them, so as by their weight to press the infusion through the pores of the skin in about 4 hours ; yet, as it was said at the same time, that the skins are filled up with the same water which had been pressed out 10 times successively, and that the whole operation takes but one day and one night, this leaves but 2^ hours for each time. The skins are then taken to the river and washed, and are ready for the dyeing. The whitest skins are laid aside for the red and yellow leather. (The operations in dyeing follow, but are here omitted.) To soften the skins after dyeing, they are harassed by a knife, the point of which is curved upwards. RUST, is the orange-yellow coat of jieroxide which forms upon the surface of iron exposed to moist air. Oil-paint, varnish, plumbago, or a film of caoutchouc, may be employed, according to circumstances, to prevent the rusting of iron utensils. RYE, consists, according to the analysis of Einhof, of 242 of husk, 65-6 of flour, and 10-2 of water, in 100 parts. This chemist found in 100 parts of the flour, 61-07 of starch, 9-48 of gluten, 828 of vegetable albumen, 3'28 of uncrystallizable sugar, 1109 of gum, 638 of vegetable fibre, and the loss was 562, including a vegetable acid not yet investi- gated. Some phosphate of lime and magnesia are also present See Gin. , s. SABOTIE^RR The apparatus for making ices, called " sabotiSre," is composed of two principal parts— a pail which is indented towards the top and covered ; and the saboti^re, or inner vessel, slightly conical, which is inserted in a pail, on which it rests by a projecting border or rim ; this vessel is closed at the bottom like a cup, and open at the top to admit the creams to be iced. It is closed at the top by a cover furnished with a handle and a hook, which fastens it to the rim of the vessel. This apparatus works as follows :— The freezing mixture, composed of sulphate of soda pulverized and hydro- chloric acid, IS turned into the pail, and the creams to be iced into the inner vessel ; iU cover is then fastened by the hook, and the vessel is set into the pail among the freezing liquid ; then taking the whole by the handle of the saboti^re, an alternate motion of rotation is given to it for about a quarter of an hour, when the cream is sufficientlv frozen. The cover is opened from time to time, and the mixture well stirred with a spoon adapted for the purpose. The freezing mixture must be removed every 15 or 20 minutes. There is a measure for the freezing mixture, which contains 2 parts of salt and 1 of acid. Tlie pail is furnished with a handle, and is surrounded with thick woollen cloth to exclude the effect of outward air. tf68 SADDLER'S IRONMONGERY. SACCHAROMETER. 569 4i 1 t ' SACCHAROMETER is the name of a hydrometer, adapted by its scale to poin« rder to be taken out by copper rakes and shovels, and thrown into draining- hoppers, plac?a near the edges of the pan. The drained sulphate of soda must be after- wards washed with cold water, to extract all the adhering sal ammoniac. The liquor thus freed from the greater part of the sulphate, when sufliciently concen- trated, IS to be drawn off by a lead syphon, into the crystallizers, where, at the end of 20 or 30 hours, it affords an abundant crop of crystals of sal ammoniac. The mother- water may then be run off, the crystallizers set aslope to drain the salt, and the salt itself must be washed, first by a weak solution of sal ammoniac, and lastly with water. It must be next desiccated, by the apparatus yig. 1228, into a perfectly dry powder, then put^mto the subliming stoneware balloons, by means of a funnel, and well rammed down. The mouth of the bottle is to be closed with a plate or inverted pot of any kind. The fire must be nicely regulated, so as to effect the sublimation of the pure salt from the under part of the bottle, with due regularity, into a white cake in the upper part. The neck of the bottle should be cleared from time to time with a long steel skewer, to 574 SAL AMMONIAC. SALTS. 575 li the internal surface of the pots ; the vapour being received and condetised into cakeSj ^Uh^ bTuoons of green glaTset over thlir mouths. The salt, when taken out and fr^ed bv scraping from any adhering ochreous or other impurities, is ready for the marfee^ b^ine sold in hollow spherical masses. The residuum in the pots or bottles may be partially worked up in another operation. The greatest evil is produced by the mixture or even contact of iron, because its peroxide readily rises in vapour with the sal ammoniac, and tinges it of a red or yellow colour. . , ,. r ^i. v» ;«*^ Tlie most ordinary process for converting the ammomacal liquor of the gas-works into gal ammoniac, is to saturate it with sulphuric acid, and to decompose the sulphate thus formed, by the processes above described. But muriatic acid will be preferred, where it is as cheap as sulphuric of equivalent saturating power; because a tolerably pure sal ammoniac is thereby directly obtained. As the coal-gas liquor contains a good deal of sulphuretted hydrogen, the saturation of it with acid should be so conducted as to burn the disengaged noxious gases in a chimney. Formerly human urine was very extensively employed, both in this Country and in France, in the manufacture of sal ammonmc ; but Bince the general establishment of gas-works it has been, I believe, abandoned, llie pro- cess was exceedingly offensive. * x j- i.„. ♦!,.«« The best white sal ammoniac is in spheroidal cakes of about one foot diameter, three or four inches thick in the middle, somewhat thinner at the edges and is semi-transparent or translucent. Each lump weighs about one quarter of a cwt As it »« easily volatil^ed by heat, it may be readily examined as to its sophistication with other salts. Sal ammonmc hL a certain tenacity, and is flexible under the hammer or pestle. It is principally used in tinning of cast-iron, wrought-iron, copper, brass, and for makmg the various ammomacal ^inScaUacToT/near Glasgow, 7200 gallons of ammoniacal liquor, ^^^f ^"f JTff^'^y from the gas-works, are treated as follows :-The liquor is first 'f.t'fi«^.^y,^'«.Xii.J? from a waggon-shaped wrought-iron boiler, into a square cistern of iron Imed y«h l^^^ 4500 lbs. of sulphuric acid, of specific gravity 1-625. are then slowly added to the sorn^ what concentrate distilled water of ammonia. The produce is 2400 gallons of 8«lphate of ammonia, sUghtly acidulous, of specific gravity 1;150, being of such ftrength as to deposit a few crystals upon the sides of the lead-lined iron tank m which the sahne com- bination is made. It is decomposed by common salt „Vo: Jnn«n From the 7200 gallons of the first crude liquor, 900 gallons of tar are ^ot by subsidence and 200 gallons of petroleum are skimmed oflf the surface. The tar is converted, by a moderate boiling in iron pans, into good pitch. A patent wa? oblaineJin 1840, for improvements m the "'jnujacture of this article, b^ Mr. H. Waterton. Two modes of operating are described ; the first consists fJ^f'^SJ' saturated solution of common salt in water, and mixing with it a quantitjr of finely pul- verised carbonate of ammonia, about equal in weight to the salt contamed in the soluti^ The mixture is agitated in a close vessel for six or eight hours, and as """^^f^'Tbonic^ is infused therein as it will absorb (but the introduction of the gas is not absolutely ne^s- sary, although the patentee prefers it); the liquid is then separated ^^^^^^^ jl'^^^' by filtration and pressure. The solid matter is chiefly bi-carUnate of soda, and the bquid holds in solution muriate and carbonate of ammonia, and common salt, and sometimes a small portion of the bi-carbonate of soda, , ^ r ^- u-;„« ^;-_ The liquid is now placed in a distilling vessel, and the carbonate of ammonia being dis- tiUed ovlr into a suitable receiver, a solution of munate of ammonia and common ^ t remains in the stilL This solution is evaporated, by heat, to such » consistency a^ will cause the separation of the common salt, by-crystallisation, and the salt, thus crystoll^^d U evaporated from the liquid by any convenient method. The liquid ^t^en evaporated until it attains the proper specific gravity for crystallismg, and it is transferred in osmta. ble utensils for th^ purpose. The crystals, produced by these ^f "«'.«•;« "^'^J^iC muriate of ammonia, anS then pressed and dried may be brought to market without further preparation, or they may be sublimed into cake sal ammoniac. The otheV mode of manufacturing sal ammomac consists m takmg * quantity of hquid. containing ammonia, either in the caustic state or combined with carbon, ^^y^'iosulphur.^ or hydrocyanic acid (such as gas ammoniacal liquor, or bone ammomacal l^q^or) aiid rectifying it, bv distillation, until the distilled portion ^ontams from twenty to twenty- five per ?ent of carbonate of ammonia. If the h^quid contains any other ^j^s^an those above mentioned, a sufficient quantity of lime is used in the distillation to decompose the ""iSrih^UleVliquid being now mixed with as large a quantity of powdered common salt as it wiU dissolve, is agitated for several hours, and as °™"<^V ^!^"'^/J;^^/!t is infused into it as it will absorb. The remainder o the operation is the same a^ before described in the first method of manufacturing sal ammomac-^Newton s Jmmal, C. S. xxii. 35 SALAMSTONE. See Lapidabt. SALEP or SALOUP, is the name of the dried tuberous roots of the OrchU,\m' oofttlfrom Pe^^and Asia Minor, which are the product of a great many ?Pecies of the i^rAuZsrJaotZ^n eountry were cleaned, scraped steeped for a short t^e m ^^po^str^rsS'rr.^^^^ J;fS,e terk onL whUe^iUow (Saiix att„)^ wme other willows, and some poplars. It has a very bit er taste. SAL PRUNELLA, is fused nitre cast into cakes or tails. SAL VOLATILE, is sesquicarbonate of ammonia. f^,^^^^6^h^^lt:tS^^li^os,^'^^'> of soda and an»>oni. SALT OF AMBER, is succmic acid. SALT OF LEMONS, is citric acid. SALT OF SATURN, is acetate of lead. SALT OF SODA, is carbonate of soda. SALT OF SORREL, is bi-oxalate of potassa. SALT OF TARTAR, is carbonate of potassa. SALT OF VITRIOL, is sulphate of zinc. SALT PERLATE, is phosphate of soda. SALTPETRE, is nitre, or nitrate of potassa. • 'siL?S,'are1.S^^^^^^^^ compounds, anciently studied under the fireek title of Ha/ur^v. At one period every inorganic substance readily soluble m water was rec-Sdedis a sS ; and'^aflerwaids, every substance soluble in five hundred ti^esitr^i-ht of water. Thus both acid and alkaline bodies cam- to be enrol cd among ^ts. bariatTerly, the combinations of the acids witii alkalis, earths, and metaiuz calces (^ow s?yled ox^^^^^^^ were aloae thought to be entitled to the denominalion of ^Its. m conLuntce of thei resemblance in appearance, and supposed analogy in composiuon, tneuUna^ salt Since Sir H. Davy demonstrated that this substance contain«^ neither icid o^iraYi^e r^^^^^^^^ that it consisted of chlorine and the metal sodium U« JeneraUty of chemists found it impossible to include salts under one categorjr of con»U. tut"ou ; while a few hare rashly offered to cut the knot, by excluding from the saline family, chloride of sodium, the patriarch of the whole. StUts may be justly divided into three orders : ^ ., x. -a «».i«««»-. 1. The binary, consisting of two single members; such as the bromides, cwonaes, cyanides, fiuorides, iodides, carburets, phosphurets, sulphurets, ^-C- 2. The bi-binary, consisting of two double members; such as the borates, bromaie*, carbonates, chlorates, sulphates, sulphites, hyposulphites, sulphohydrates, &c. 3 The ternary, consisting of two single members of one genus, and one member ol an- other ; such as the boro-fluorides, silico-fluorides, sulpho-cyanides, chloriodides, &c. The species of each order may exist in three states, constituting neutral salts, super- salts, and subsalts ; as for example, the chloride of sodium, the bisulphate of potassa, the subnitrate of lead, &c. . , u e In the above arrangement, cyanogen is allowed to represent a simple substance, trom its forming analogous compounds with chlorine and iodine. The neutral state of salts is commonly indicated by their solutions not changing the colors of litmus, violets, or red cabbage ; the sub-state of salts, by their turning the violet and cabbage green ; and the super-state of salts, by their changing the purple of litmus, violets, and cabbage, red; but to the generality of this criterion there are some exceptions. The atomic theory may be advantageously resorted to, in this predicament. 1. When one prime equivalent of the one member (whether single or double) of a salt, combines with one prime of the other member, a neutral salt is the result, as in chloride of sodium or nitrate of potassa. Z. When two primes of the electro-negative member combine with one prune of the electro-positive, a supersalt is formed, as bichloride of tin, or bisulphate of potassa. 3. When one prime of the electro-negative member combines with two or more prim^ of the electro-positive, a subsalt is produced, as the subacetate and subchromate of SALT* The salt manufacture of Droitwich, Worcestershire, existed at a very early period : it is mentioned as in operation at the time of the Roman invasion; then it was 676 m SALT, SEA. madei, „se to .he surface t&'t ^r" ^'^ o^&Ct"'' «''='« o?"^"™ the freshwater spring. ;, *'";™'' '» wo^'e; for in ascend^^ K '^''.'"S- Tliia process tie salt, which wm TOnduXj k ^ ""^ '"'^wed in strenJ^f ^T^'' ""d miiins wUh There has been recently nhi • ^ '«rmerly, it varied between salt: bv usino- T,«. '^^tJUiiJ Obtained a nafon* r . ""cen per annum manufactured „?^l!-l'''''' ""'' ^5"»toI. 11 er' »rl "^ " ""P"--'*! largelv purposes; the rest Is utedil^fl* /"'"«' «<»» are used f.,r I "^^'''''''f '0,000 folS varies from 2 to 2-^ " JP'""' ""d softer than ~lc„rt "'"■* ' " '' ""rly as hard 21 Posure to heat, it coS,o„rdi;.''"'''' '' '» ~'»rlesMrinTce'„f''"- "' 'P^'fl' g™vi? ftsion at an elevated t^^iLlf'*P"».'« ; but some Cdi „r ' ?"■ '™"sparent. On™, been oriyinally subjected to^he*'? '''""'"^'"ce which h J J '*'■ ""'" W^'Ir into According to M/GaTl, ° *c 'mT "^ ^'^- '^"^ '» '^''" !««"«« 35 81 parts of the'sajt .IT "*■ *"'" *"™'ve- 35-88 " 3' •' 'emperature 570» ^r 37- J4 62-5» iwr ,. ^0-38 ~ ]40-0» Jime, niagnesia, soda, muriatlV^? "^""'"^ ^^^ qualities Tho ^^^ '*''"^J"n matters «late of diifusion, fcc! """''* ^^^agnesia and pota h 4u Jen ' vi'' V^^ ^^^^^^^^^ «? Muriate of potash has hpo ^ ""amen, oxyde of iron, clay in a Berchtesgaden in Bavark of R n'-^'-'^' '" the waters of th. • of Rosenheim. ^"^'^^ ^'^H-U-n in the territor? oT&L^^rrr^ •" l'^ ^^^"^^"^ ^^ The more heterogeneous the ..n .u ^i2t>onrg, and m the salt springs different saline constituenTs •L'flV^^ "^^^ . ^ may serve to show approxt'«r.f t"' * ^^"<^ate hyi-imeter ni ""^?P^«^«' affinity of itt of a saturated solution of iTf^^ *^^ ''"^^'^y of the?X T '/i""5^^ ^" saturated brne «>lutio?. ^^ ^^^ ^^-«s and'silin^^ eUit^utn^U^^^ -f«^ VenZi^Y^ the^dri&h^*- ^" ^^^ «>- of this salt th ^' ^'" '' ^^ ^'^ .haped,Thlt?V^e:-^^^^^^ jurface of the saline soS'^-' ? *^ * ^^"ow rec'an"n,« ' *^^"^.^he funnel or hop^r! floating cube, upon wMch r "* I^^ *^0"^se of its evarS"^- ^^'^"^'^^ ^^ich forms a?^* SALT, SEA. 577 A Table of the results of the Analyses of several varieties of Culinary Salt. Chloride Muriate Muriate Sulphate Sulphate Sulphate Clay and Oxyd« | Origin of the Salt. of of Mag- <.f of of Mag- of other ill- of Sodium. nesia. Lime. Soda. nesia. Lime. soluble bodies. iron. Sal-^emofVicJ'^!;^^^ ( red 99-30 99-80 ^^^ — _ — 0005 0-020 0-002 Cheshire, crushed 98-33 0-02 — — — 0-65 — 0-002 Salt from Salt Sprintas : Schonbeck, Westphalia 93-90 0-30 — 1-00 0-80 M-""' V^^"' 97-17 0-25 — 2-00 0-58 93-59 0-61 — 5-55 0-25 Chateau Salins 97-82 2-12 White of Sulz - 96-88 3-12 Ludwisshall, middle grained 99-45 — — 0-05 — 0-28 Koenigsborn, Westphalia 95-90 — 0-27 — — 1-10 Sea salt, half white 97-20 0-064 — — 0-050 0-120 0-070 96- 93-55 0-30 ^_^ 0-45 2-35 Common Scottish salt 2-80 — 1-75 1-50 l.vmirtirton, common - 93-7 l-I — — 3-50 1-50 2-00 9R-8 n.R _ ^^^ , 0-5 0-1 Cheshire, stoved 98-25 0-075 0-025 — 1-55 The geological position of rock salt is between the coal formation and the lias, Th« great rock-salt formation of England occurs within the red marly or new red sandstone, the hunttr-sandstein of the Germans, so called, because its colors vary from red to salmon and chocolate. This mineral stratum frequently presents streaks of light blue, verdigris, buff, or cream color; and is chiefly remarkable for containing considerable masses or beds of gypsum. At Northwich, in the vale of the Weaver, the rock salt consists of two beds, together not less than 60 feet thick, which are supposed to con- stitute large insulated masses, about a mile and a half long, and nearly 1300 yards broad. There are other deposites of rock salt in the same valley, but of inferior im- portance. The uppermost bed occurs at 75 feet beneath the surface, and is covered with many layers of indurated red, blue, and brown clay, inlerstralified more or less with sulphate of lime, and interspersed with arsillacc »us marl. The second bed of rock salt lies 31^ feet below the first, being separated fron it by layers of indurated clay, with veins of rock salt running through them. The lowest ocd of salt was excavated to a depth of 1 10 feet, several years ago. The beds or masses of rock salt are occasionally so thick, that they have not been yet bored through, though mined for many centuries. This is the case with the immense mass of Wieliczka, and the lower bed at Northwich. But in ordinary cases, this thickness varies from an inch or two to 12 or 15 yards. When the strata are thin, they are usually numerous ; but the beds, layers, or masses never exhibit throughout a great extent any more than an illusory appearance of parallelism ; for when they arc explored at several points, enlargements are observed, and such diminutions as cause the salt to disappear sometimes altogether. This mf.neral is not deposited, therefore, in a geolosical stratum, but rather in lenticular masses, of very variable extent and thick- ness, placed alongside of each other at unequal distances, and interposed between the coursec of 'he other formations. Sometimes the rock salt is disseminated in small masses or little veins among the cal- careous and argillaceous marls which accompany or overlie the greater deposites. Bitu- men, in small particles, hardly visible, but distinguishable by the smell, occurs in all the minerals of the saliferous system. It has been remarked, that the plants which grow generally on the sea shores, such as the Triglochinum maritimumj the Salicomia, the Salsola kali, the Jster trif»lium, or fare- well to summer, the Glaux maritima, &c., occur also in the neighborhood of salt mines and salt springs, even of those which are most deeply buried beneath the surface. The interior of rock-salt mines, afler digging through the strata of clay marl, &c. is extremely dry; so that the dust produced in the workings becomes an annoyance to the miners, thouch in other respects the excavations are not at all insalubrious. Salt springs occur nearly in the same circumstances, and in the same geological form. 578 SALT, SEA. SALT, SEA. 579 I m \ ! *tion as the sail rock. It has been noticed that salt spines issne in Mnem! from thm npper portion of the saliferous strata, principally froJS.fS^'cl!rm^sV^^ however occur, where the salt springs are not accompanied by rock salt, and where t^ ^mroTl^T '" "'""^ ^''" '^' "^""^^ themselves, which thus^oistUutrS^e only It has been imagined that there are two other periods of geological formation of this •ubstance ; one much more ancient, belonging to the transition series of rX the othe? relatively modern among secondary strata. To the former has been relrred the salffor! ma .on of Bex, that of Cardonne, Sec. But M. Brongniart assigns valid reasons f^^^ S^%h^'' ^"PPosition. M. Beudant, indeed, refers to the secondary strata a^ve t^^ chalk, the rock-salt formation of Wieliczka, and of the base of the Carpathians placng these among the plastic clay and lignites. p«""ans , piacing The mines of rock salt do not appear to possess any determiftate elevation unon the surface of the earth Immense masses of it are met with at very great depths below the level of the sea, (the mine of Wieliczka is excavated 860 feet beneath the s^nTanS others exis at a considerable altitude, as that of Haliein near Salzbourg, which is 3300 SS^"^j;V h ^^^^.l«^^^^ ''\^^^ '^^ ^«Ii"^ ^ock of Arbonne in Savoy, which is ne^iy 4000 feet higher, situated at the great elevation of 7200 feet above the level of the sea Inh.r'f'^"'"'^^ '"'^^ ^^/io"f P-'-petual snow. Therock is amass of saccharoid and anhjdrous gypsum, imbued with common salt, which is extracted by lixiviation : after which the gypsum remains porous and light. i«"un, aiier The inland seas, salt lakes, and salt marshes, have their several localities obvionslv independent of peculiar geological formations. The ocean is, however, the most maS- cent mine of salt, since this chloride constitutes about one thirtieth part of its weight • ^hL^ ?h'7"''^ ^f""''^ throughout its waters, when no local cause disturbs trequil mao.naJt' ^^'"^f ^\ P^^P^^ion of salt held in solution in the open sea, is 38 parts in 1000, and the smallest 32. In a specimen taken by Mr. Wilkinson, out of the Red Sea at Berenice, I found 43 parts of salt in 1000. The specific gravity of the water was 1035, Were it requisite to extract the chloride of sodium from sea-water bv fuel alone manv countries even maritime, would find the process too costly. The salt is therefore ibuT/- ed from It in two different manners; 1. by natural evaiK)ration alone ; 2. by natural and ti^ffn^ ^^«P«;at.on combined. The first method is employed in w'arm r^ is, under the form of saline tanks, or brine reservoirs, called also brine-pits These are lar^e shaUow basins, the bottom of which is very smooth, and formed of day. They are el! cavated along the sea-shore, and consist of — ^ iney are ex- .nH't^Lll^^VK*^""''"*''' ^^^^^^ ^^*" ^^^ ^^^^^' brine-pits, which is dug between them and the sea. This reservoir communicates with the sea by means of a channel provided with a sluice. On the sea-shore, these reservoirs may be filled at high water, though the tides are rather inconvenient than advantageous to brine-pits. j e luc 2dly. The brine-pits, properiy so called, which are divided into a number of compart- meats by means of little banks. All these compartments have a communication with each other but so that the water frequently has a long circuit to make, from one set to another Sometimes it must flow 400 or 500 yards, before it reaches the extremity of this sort of P.Knf.i!;v Jr ^*''.'7^^*vjJ««ns have a number of singular names, by which they arc techmcally distinguished. They should be exposed to the north, north-east, or nor^ The water of the sea is le* into these reservoirs m the month of March, where it » exposed on a vast surface to eYaporalion. The first reservoir is intended to detain the water till its impurities have subsided, and from it the other reservoirs are supplial as their water evaporates. The salt is considered to be on the point of crystallizing when tiie water begins to groAt rec Soon after this, a pellicle forms on the surface which breaks, and falls to the bottom. Sometimes the salt is allowed to subside in the first com- partment; at others, the strong brine is made to pass on to the others, where a larger ^^ ro dSdVr^r "^- '" ^^^'^^ ^^^^ ^'^ '''' '' ^'^^ -^' -'^ ^^" ^p- '^* The salt thus obtained partakes of the color of the bottom on which it is formed : and IS nence white, red, or gray. t» tl^''^^f' contains, ii, 1000 parts, 25 of chloride of sodium, 6-3 sulphate of magnesia. 3-6 chloride of magnesium, 0-2 carbonate of lime and magnesia, 0-1 sulphate of lime, be- l^^ 5o'oo ^' sulphate and muriate of potash. It also contains iodide of sodium, and bromide of magnesium. Its average spec. grav. is from 1*029 to 1-030 Sea-water and weak brines may be cancentrated either by the addition of rock salt by spontaneous evaporation in brine-pits (see supr^), or by graduation. Houses for the last purpose are extensively employed in France and Germany. The weak brine is pumped into an immense cistern on the top of a tower, and is thence allowed to flow down the surface of bundles of thorns built up in regular walls, between parallel wooden irames. At Saiza, near Schonebeck, the graduation-house is 5817 feet long, the thorn walls are from 33 to 52 feet high, m diflferent parts, and present a total surface ol 25,000 square feet. Under the thorns, a great brine cistern, made of strong woodea planks, is placed, to receive the perpetual shower of water. Upon the ridge of the graduation-house there is a long spout, perforated on each side with numerous holes, and furnished with spigots or stopcocks for distributing the brine, cither over the surface of the thorns, or down through their mass ; the latter method affording larger evaporation. The graduation-house should be built lengthwise in the direction of the prevailing wind, with its ends open. An experience of many years at Salza and Durrenberg has shown, that in the former place graduation can go on 258, and in the latter 207 days, on an average, in the year ; the best season being from May till August. At Diirrenbei^, 3,596,561 cubic feet of water are evaporated annually. According to the weakness of the brine, it must be the more frequently pumped up, and made to flow down over the thorns in different compartments of the building, called the 1st, 2d, and 3d graduation. A deposite of gypsum incrusts the twigs, which requires them to be renewed at the end of a certain time. Figs. 1230 A 1231 represent the graduation-house of the salt-works ftt Durrenberg. o, a, a, are low stone pillars for supporting the brine cistern 6, called 1230 1231 the sooleschiff. c, c are the inner, d, d the outer, walls of thorns ; the first have per- pendicular sides, the last sloping. The spars e, e, which support the thorns, are longer than the interval between two thorn walls from /to g,^g. 1231, whereby they are readily fastened by their tenons and mortises. The spars are laid at a slope of 2 inches in the foot, as shown by the line h, t. The bundles of thorns are each l\ foot thick, from 5 to 7 feet long, and are piled up in the following way : — Guide-bars are first placed in the line fe, /, to define the outer surface of the thorn wall ; the undermost spars m, n, arc fastened upon them ; and the thorns are evenly spread, after the willow-withs of the bundles have been cut. Over the top of the thorn walls arc laid, through the whole length of the graduation-house, the brine spouts o, o, which are secured to the upper beams ; and at both sides of these spouts are the drop-spouts p, p, for discharging the brine by the spigots », *, as shown upon a larger scale in^g. 123'/-. The drop-spouts are 6 feet long, have on each side small notches, 5 inches apart, and are each supplied by a spigot. The space above the ridge of the graduation-house is covered with boards, supported at their ends by binding-beams q. r, r, show the tenons of the thorn-spars. Over the soole- schiff 6, inclined planes of boards are laid for conducting downwards the innumerable showers. The brine, which contains at first 7*692 per cent, of salt, indicates, after the first shower, 11*473 ; after the second, 16*108 ; and after the third, 22. The brine, thus concentrated to such a degree as to be fit for boiling, is kept in great reservoirs, of which the eight at Salza, near Schonebeck, have a capacity of 2,421,720 cubic feet, and are fi- nished with pipes leading to the sheet-iron salt-pans. The capacity of these is very dif- ferent at different works. At Schonebeck there are 22, the smallest having a square surface of 400 feet, the largest of 1250, and are enclosed within walls, to prevent theii being affected by the cold external air. They are covered with a funnel-formed or pyra- midal trunk of deals, ending in a square chimney, to carry off the steam. Figs. 1233, 34, 35, represent the construction of a salt-pan, its furnace, and the ■alt store-room of the works at Durrenberg; /g. 1235 being the ground plan, yig. 1324 ( ' (. i w 580 SALT, SEA. 1283 the longitudinal section, and ^g. 1233 the transverse section, a is the fire-erate which slopes upwards to the back part, and is 31J inches distant from the ^ttom^o7 the pin The ratio of the surface of the grate to that of the bottom of the pa^ is as 1 to 59^^5 * brfck: sm^othl^^^^^^^^^^ ''' ^'-P'V^ ' ''• '''' '^^^ ^^^ under re;ins law w'h bricks, smoothly plastered over, from 6 to c, m Jig. 1234. Upon this bed the pillars d d &c., are bu.lt m a radiated direction, being 6 inches broad at the bottom, and taperinl^' to H inch at top. The pan is so laid that its bottom has a fall towards the Sfe of 2| inches; see «, /, ^g. 1234. The fire diftuses Itself in all directions under the pan, proceeds thence through several holes g, g, g, into flues A, A, A, which run round three sides of the pan ; the burnt air then passes through i, ^g. 1 235, uiv- der other pans, from which it is collected in the chimneys fc, fc, to be conducted into the drying-room. At /, /, there is « A L'!!.'^"u"' "^ ""* '.'''"'' *"" '""'^ " B™''''"' ascent above the level of the fire-orate «g«r<. ll'''rTertai„"',^^^^^^^^^ T "'""f' '° '""^ "« "" smoke.Xhly chance to ttfaVhpU (L firiiaf/iJ^^^^^ ''^''!.'"^r'! "'P^^'"''" "Pon each side of "•« asa pit (see fi gs. 1234 & 1235), into which cold air is admitted by the flue «, r II 1 " TV ^^ Ik ^ ^ II 0* / Jk. SiliS \\aa , I 1"^ 1 — M — : ^ ''T^ IL J^ Z .'^ II- ^ iV ^ r- 1 1235 Tr^n't^^yT'^'''^ ^'^*^x' ^* ^' conducted through iron pipes ,, and thence escanes at L which the pan UsnppuJd^ffiual^ brine' ""*'' ""**• "' "' '"'"' *« P'P" ''^ DacriptimoftkeSteam4ruvk,mfig.nZi thiba'lrl^fu^oZ&nV/'l^ari 'rare-stl C^' Z"" T!"'"' """ '» """^ "^ upon the bearers d d Af\ 7 « J;-« j ^^ , * ^^® PiHars c, c, are sustained for fixing dowrthe L A J'/' kT r^'^T'"^^' S^'^^^^^ " '"^de in the beams, lor nxmg aown ine lour boards which form the bottom of the stpam wnv Tn #*..•: SALT, SEA. 581 two other rows of boards are hooked on so as to cover the pan, as shown at h Whenever the salt is sufficiently drained, the upper shelves are placed in a horizontal position ; the salt is put into small baskets, and carried into the stove-room, t, j^, is the steam-trunk ; l, m, is a tunnel for car- rying off the steam from the middle of the pan, when this is uncovered by lifting the boards. In proportion as the brine becomes con- centrated by evaporation, more is added from the settling reservoir of the gradu- ation-house, till finally small crystals ap- pear on the surface. No more weak brine is now added, but the charge is worked off, care being taken to remove the scum as it appears. In some places the first pan is called a schlot-plan, in which the concentration is carried only so far as to cause the deposition of the sludge, from which the saline solution is run into an- other pan, and gently evaporated, to pro- duce the precipitation of the fine salt. This salt should be continually raked to- wards the cooler and more elevated sides of the pan, and then lifted out with cullender-shovels into large conical baskets, arranged in wooden frames round the border of the pan, so that the drainage may flow back into the boiling liquor. The drained salt is transferred to the hurdles or baskets in the stove- room, which ought to be kept at a temperature of from 120° to 130° Fahr. The salt is then stowed away in the warehouse. The graduation range should be divided lengthwise into several sections ; the first to receive the water of the spring, the lake, or the sea ; the second, the water from the first shower-receiver ; the third, the water from the second receiver; and soon. The pumps are usually placed in the middle of the building, and lift the brine from the several receivers below into the alternate elevated cisterns. The square wooden spouts of distri- bution may be conveniently furnished with a slide-board, attached to each of their sides, to serve as a general valve for opening or shutting many trickling orifices at once. The rate of evaporation at Moutiers is exhibited by the following table : — Number of Showers. 1 and 2 3, 4, 5, 6, 7, 8, and 9 - 10 - - - Total Surface of the Fagfots. 5158 square feet 2720 550 Specific Gravity of the Brine. Water evaporated. 1-010 1-023 1-072 1-140 0-000 0-540 0-333 0-062 Total evaporation Water remaining in the brine at the density of 1-140 Water assigned at the densitv of 1-0 10 0-935 1-065 1000 From the above table it appears that no less than 10 falls of the brine have been required to bring the water from the specific gravity 1-010 to 1-140, or 18° Baume. The t^aporation is found to proceed at nearly the same rate with the weaker water, and with the stronger, within the above limits. When it arrives at a density of from 1*140 to 1-16, it is run off into the settling cisterns. M. Berthier calculates, that upon an average, in ordinary weather, at Moutiers, 60 kilogrammes of water (13 gallons, imp.) are evaporated from the fagots, in the course of 24 hours, for every square foot of their surface. Without the aid of currents of air artificially warmed, such an amount of evaporation could not be reckoned upon in this country. In the schlotiing, or throwing down of the sediment, a little bullock's blood, previously beaten up with some cold brine, promotes the clarifica- tion. When the brine acquires, by brisk ebullition, the density of 1-200, it should be run off from the preparation, to the finishing or salting pans. The mother-water contains a great deal of chloride of magnesium, along with chloride of sodium, and sulphate of magnesia. Since the last two salts mutually decompose each other at a low temperature, and are transformed into sulphate of soda, which trvstallizes, and muriate of magnesia, which remains dissolved, the mother-water witk 582 SAND. SANDAL WOOD. 583 Ihis view may be exposed in tanks to the frost durine winter whpn it nffVirri. th^^ «.- cessive crystamne deposites, the last being sulphate of s^SlrneLly pire '^"^ *""• The chloride of magTiesium, or bittern, not only deteriorates the salt* very much but occasions a considerable loss of weight. It may, however, be most adUntYge^usly eot nd of and converted into chloride of sodium, by the following simple expedfenr-Le quick mie be introduced m equivalent quantity to the magnesia present and i^wilpre cipitale this earth, and form chloride of calcium, which will immediately reac Zon thi sulphate of soda in the mother-water, with the production of sulphate of limeandrhlnrid! of sodium. The former being sparingly soluble, is easily separated iTme Ireover rhwTnf' ^'r'"^ -^^ '^^^"5" of magnesium, but with the effect of merelTsubst tutine fn S! ^^^"7"\^" 't« ^^^ad- B»t in general there is abundance of sulphaie of S in brine springs to decompose the chloride of calcium. A still belter way of proce^^S with sea-water, would be to add to it, in Ihe settling tank, the quantity ^?Ueequh^en? l^T^tTT'-'^^^'^^?/'* ^^^^^'^'^ ^^P°^'t« °^ this earth would be obtained, anhesami {^^Xva»^^^^ '^ ^"^^^^"^- "'^^^^ ^'"^ p^"^^^ '"^y ^ ^^^'y -"eS In suinmer, the saturated boiling brine is crjstallized by passing it over verfcal ronP« • Set7..'m^"'*^f^'^^'Tx.'"^*'-^^ (110,000 yards) are mounted in a" aTaVtmer'i S i- J^??-^^^':^- ^*^^" *^^ ««'t ^^^ ^^'^^^ a crust upon the ropes aW 2* nches thick, It IS broken off, allowed to fall upon the clean floor of the aXtUnt and then gathered up. The salting of a charge, which would lake 5 or 6 days in the nan^s T^:^i^ei:^^sja^^ '^' ''' -^^— - - -- abunrt.%reri The boilers constructed at Rosenheim, in Bavaria, evaporate 3^ T)oiind«c nf «rnfon a>. every pound of wood burned ; which is rWoned a fUraWe esuU ^"1 o^ on described under Evaporation, would throw off much more. °^ «rthi r J*"^- ^^^^"^'"^ and principal brine springs are in Cheshire ; and the chief part ofthe Cheshire salt, both fossil and manufactured, is sent by the river Weaver to Liver ?^1^^J; •"^" proportion of it being conveyed elsewhere, by canal or llnd cardaeT JnH • w '"f «P"»?V" Staffordshire, from which Hull is furnished with whfte sa!t * jnd m Worcestershire, from which Gloucester is supplied. If to the 7uantiTv .hinnil by the Weaver, 100,000 tons of white salt are ad.led annually for nternrcl' utptbl and exports exclusive of Liverpool, the total manufacture will be approached verv near ly ; but as there IS now no check from the excise, it is impossible to Leer tain heLX il't'fi":'''^ '■ '™^V, '^"""'^^'^^ ^' «°°^^ «^ the Cheshire manufactories, to Jtre^^ti^ l«nH "* ' T^ '' principally exported ; some to Ireland, but chiefly to Befeum and Hoi land.«* The average quantity of rock salt sent annually down the rive" Weaver ^^TI^^u'"^' ? Cheshire, between the years 1803 and 1834 inclusive was 86 000 ^Z tt C'lSis'Vhe'L""''"^ '^^"^^ '''/'I'- ^" *'^ y^^' ''''> an7tl^l:L't?7^Vo^^^^^ flJff r T ^. ^^-^'^^^ quantity of white salt sent annually down the Weaver from the manufactories m Cheshire during the same period was 221 q^i Vh!. ^^*7 ' being 383,669, in the year 1832, and the least being 12'o,486; I'the '"^ar 'iLl '' ''''''''' M. Clement-Desormes, engineer and chief adimnaire of the great salt-works of Dienre S>n onn?' '"^''"' "'^ '^l' ^^' ^"'^^"^^ consumption of that kingdom is rl'ier l^eThaS 200,000 tons per annum, being at the rate of 6I kilojrrammes for each individual of^ population estimated at 32,000,000. As the retail price of salt in FranceTs 10 soi n- kilogramme (Of 2i lbs. avoird.), while in this counti^ it is not more fhanTs^us H pennv^ Its consumption per head will be much greater with us ; and, takin/i^o accounT tl^' immense quantity of salted provisions that are used, i may be reckoned at 22 Ihl whence our internal consumption will be 240,000 tons, instU of mOOO as quo^^^ above, from the tables published by the Board of Trade i"",""", as quoted In J836, 9,622,427 bushels, of 56 lbs. z= 240,560 tons of salt, value 173 923/ wer^ exported from the United Kingdom, of which 1,350,849 bushels wentrKusLa Ys^^ ORR to Belgium; 314,132 to the Western coast of Africa • 1293 560 to tL Br I, if^^^^ American colonies; 2,870,808 to the fnited StatesTf Ame'Lf 53 299 t^ Ne^ Wales, Van Diemen's Land, and other Australian settlements 58 735 to thpR^rK West Indies ; and 90,655 to Guernsey, Jersey, Alderney a™d M^n ' m. Zh^L Irlu ^^r;?JM?^^ ^^^« 15,819,664 bushels; in 1851 18 ^5 eQsSiels. ^ *^^ obEL^Llt'n^L^hT"/^'^^- ^'- ,^--andrand'Mr.TFell have lately 8U 8 of a v?rt ca cvliin! '^"^ P^'^^"' ^^'') f ""'^ *« ^^''^ ^^"- ^he apparatus con- WK ♦i. „I K 1 ^ .'^^^^*''',"^'?f^"®^ ^^ horizontal partitions communicating each with the one below it and each with a pipe leading to a condenser. A smce isTeft between the sides of the cylinder and the partitions, to allow of steam citculS freely Khe apparatus from the top, and circulates over the partitions, and the aqueous vapour • Tables of the Keveaue, Population, Commerce, Ac., for 1835, p. 122. arising from it passes oflF to the condenser, and on its way becomes mixed with at- mospheric air, introduced through a suitable pipe, and issues from the condenser in an aerated state, while the water arising from the condensation of the steam admitted into the cylinder is discharged therefrom without being aerated. The apparatus may bo constructed of any suitable materials, but the patentees recommend the use of zinked or galvanized iron. SAND (Eng. and Genn. ; Sable, Fr.) ; is the name given to any mineral substance in a hard granular or pulverulent form, whether strewed upon the surface of the ground, found in strata at a certain depth, forming the beds of rivers, or the shores of the sea The siliceous sands seem to be either original crystalline formations, like the sand of Neuilly, in 6-sided prisms, terminated by two 6 -sided pyramids, or the debris of granitic, schistose, quartzose, or other primitive crystalline rocks, and are abundantly distributed over the globe; as in the immense plains known under the names of downs, deserts, steppes, landes, Ac, which, in Africa, Asia, Europe, and America, are entirely covered with loose sterile sand. Valuable metallic ores, those of gold, platinum, tin, copper, iron, titanium, often occur in the form of sand, or mixed with that earthy substance. Pure siliceous sands are very valuable for the manufacture of glass, for making mortars, filters, ameliorating dense clay soils, and many other purposes. For moulder's sand, see Founding. Lynn and Ryegate furnish our purest siliceous sand. SAND FOR GLASS MAKING. The Great Exhibition was well furnished with specimens of the finer kinds of sand ; some of which, as those from the l3l« of Wight, and the neighbourhood of Lynn, were remarkably white and beautiful By fiir the finest sample of sand ever seen in this country was, however, in the American department of the Crystal Palace, and did not fail to attract the notice of those interested in such matters. This sand was contained in two or three barrels in the southern side of the building, and seems totally free from iron and every other source of contamination. It was positiviely as white as snow, and so far as the making of glass is concerned, may rival or supersede the best flint, even if the high price of this latter article did not form an insuperable obstacle to its employment. It was from T. Gray & Co., Boston, Massachusetts ; but its geological locality was not stated. The principal exhibitors of sand for the ma- nufacture of glass were. Sir T. Mary on Wilson, of Charlton ; J. Rock, jun., of Hastings; Whittaker ath, and then passing it through a boiling balh of sandal wood and sumac Pelletier did noC 584 SCAGLIOLA. SCARLET DYE. 585 il f in 1 I* , ,;fi ! '.11 il I succeed in repeating this experiment. Accordine to Toiler xirnni cJib ^«f*«« - j r mordanted with salt of tin and dipped in a cold' aLfeSe ff\he^ 3^^ same tincture mixed with 8 parts of boiling water, become of a uperb pon^au-r^^^^^^^^ With alum, they took a scarlet-red ; with sulphate of iron, a deep viokt C brotn r^* Unluckily, ihese dyes do not stand exposure to li-ht well. ' brown-red. SANDARACH, is a peculiar resinous substance, the product of the Thuufi nrN.^iJnfn a sma 1 tree of the coniferous family, which grows in [he northern par s^? it^ei pecially round Mount Atlas. ^ Airica, e8- The resin comes to us in pale yellow, transparent, brittle, small tears of a RnliPrIP«l or cyhndr.cal shape It has a faint aromatic smell, does not'sof.en, but bVeLs Liwe^^^^^ ^J ApVt^' different resins ; one soluble in spirit of wine, somewhat resembl n" ;^^^^^^ actd(seeluRPENTiNK); one not soluble in that n>enstruum ; and a third .olubie onlv in alcohol of 90 per cent It is used as pounce-powder for strewing o4r pa/er erasur^^^^^ as incense, and in varnishes. * ^ ciasuree, Tt fAnt^i^I k^?k' 'I* ^Pl"f ^'^ the C^salpinia genus, to which Brazil wood belongs It is so called by the French, because it conies to them from Japan, which thev corrS Euron'I^r "'^^^ Z^ '^""'^ '^"^*"" ''•"' '^'y ^^"''^ "«^ have been used ardye'sTuff; Z Europe before the beginning of the 16th century. Yet the author of the article « Brazil ^ Int Jy^^«P^^'«' ««d Mr. Southey, in his History of Brazil, say that ira^tV wood is aientioned nearly one hundred years before the discoveries of Columbus and VaTcode Garni by Chaucer, who died m 1400 ; that it was known many a?es before his time and that' I^^:: 't 7r'/if '^' T^r^^ T^^^^ ^^ ^^^^ country giWng the name t^the wood as I have stated, with BerthoUet and other writers on dyeinff. The CtBsalmnia,am,nn ^h".? IT:' '^ ^'f Coromandel coast, may possibly iLe been transponrin^'^S other Malabar merchandise to the Mediterranean marts in the middle aees but the inu portation of so lumbering an article in any considerable quanti.v by Iharchan, el^s^ dyers of Europe before the discovery of the New World. ^ SARD ; see Lapidary. SATIN (Eng., Fr., and Germ.), is the name of a silk stuff, first imported from Thin. which IS distinguished by its very smooth, polished, and glossy'surfac"^ i Is wo^e^unon a loom with at least five-leaved healds or heddles, and as many corr^spondi^- tr3« These are so mounted as to rise and fall four at a time, raising and depress ii"\liern«^' \1 four yarns of the warp, across the whole of which the weft is thrXn by il^e 4uttle' 80 as to produce a uniform smooth texture, instead of the checkered work resultin^ZS intermediate decussations, as in common webs. See Textile FABRicr W% ?" woven with the glossy or right side undermost, because the four-fifths of the* war, whkh are alway's left there during the action of the healds, serve to support the shuTt l^Tn Tts ^ce Were they woven in the reverse way, the scanty fifth part of the warp thread J ti TTT^p'■A^'?r^'^P^°'■^? ^' ^°"^^ ^^ ^°« n^"^h worn bv the shultle. ^ *"*' &A1 UKAllON, is the term at which any bodv has taken its full dose or chemical in their teeth very accurately by means of a division plate ; this prevfnts iSa. ly of eize, and imparts smoothness and uniformity of action. The krger sizes Sfccular saws are made m segments and connected together by means o dove au/ A U^^^^^^ are hardened and tempered in oil; their irregularities are removed by hammering o„ ci^'ni' t'^ '^'"^ ^'' '^"^"^"^ ^y g""^^"^- ^'^^« ««veral forms of teefh do nTS'the SrouLh tf/r/r'^Y ''"'^•"'' ^'Pf"^ "P^^ '^'^'^ ^^^ ^'^ *»»««« b-«t fitted ?or 'c^^^t ' ^rough the particular sectiun, quality, or hardness of the material to be cut. The " se"" of the saw consists m inclining the teeth at the particular angle known to be the £t to facilitate the exit of the sawdust, and thereby allow the saw to operate mo'e Sous' ra?e and'i^w' . ^'""SWesented to the saw red hot; the saw rotated at a pro3 - pous rate, and is kept m cutting condition, or cool, by its lower edge bein- immersed ^PAPT TOr^r '''" '"t"' '" diameter is cut throughin a few seconds ° "^ bOALrLlULA, 13 merely ornamental plaster-work, produced by applying a pap madt of finely-ground calcined gypsum, mixed with a weak solution of FlanTer^s' gli^ mx.^rny figure tormed of laths nailed together, or occasionally upon brickwork and b^ uddin^ka surface, while soft, with splinters (^cagliole) of spar, m^rbre.granite bits of cotrete^S ppsum, or v-ems of clay, m a semi-fluid state. The substances employed to colour he spots and patches are the several ochres, boles, terra di Sienna, chrome yellow. . oc 8 11 4 8 4 12 8 he eight pints of decoction, thickr.hV„pr„S ^^h .^^^^^ "'T '''« '•««»« of "i'ric acid, of The tin is to bi divided in o eight lrtion"and?ne oTr"'"' '. '?"' """«' "' f^™'" «'»• ture every quarter of an hour. ' ™' ""^ ""^ '" "> "« P"' '"lo Ihe acid mix- mafkabfrnner?"""' "' '"'«^^' '"""* '> ^ -"• '» ''e-tify scarlet cloth in . re »«tra^dTE?s::,vi:;rtinTbua si'statt-su'^ rr- »^ -'->"™ ""o ayers to adopt his plans. l'„ fac^ the prZr bZ s n mv"^-''"' '" Pr^""*!"? scarlet- oxyde and pcroxyde of tin : and this canimi h.^M» • ' a u^ "P'.""'". » ""Jtlure of Ihe prot- murio-sulphuric acid. He also p escr brf ?he e^Hl^^ ""7 T" "'" ■"''»' '>"^"« change the natural crimson of the cochneal into scar i^th-^^^^^ ''""■'"'■™ ''"'"' '" ty of this expensive dye-stuff. See Lac Dve ^ econoroizing the quanti- ac,d to 2 pounds of carbonate of potaSrdTsid i^i^fo^'^''"!^"^ ^^ «""<=«« of arsrnious disso ve 2 pounds of crystallized sulphate o?c^^^^^^^^^ ^'^'"^ ^^^^^^ ^ «ext, solution, then pour the first pro-ressivelv into fhp .^LnH P^^^^^ ''^ water ; filter each grass-green precipitate. This beinrthiwn unonTfiu' ^V??" ^l^' Produces a rich warm water, will afford 1 pound 6 ounceronhisTautif^i^^nF; i ^"? edulcorated with oi copper 28-51, and of arsenious ac"d 7l'46 T^fs '^^^^^^^^^^ It consists of, oxyde SCHWfX^'tILT^^^^^ See CALico.p;rNTmc.^"'" '' ^PPHed by an analogous procedin,S''™dS^din^8HV™^^^ ^^- '^^ and remained for many years a profitable .errPt in iK -if ?^ ^.","'^''' *^ Schweinfurth, gs composition known; in 182?, rhafbLn Tncrnr.nnrJt"'''- ^' ^'^^'^ ^^^'"? "^^de Braconnot puk/ished, about the same time another To 'L'"r^ ^"'^' ?""^ color-works, pigment. Us preparation is very simple buHtsforrTnTon- '"^""^"^'"ring the same teresting circumstances. On mixin^^ukl narts of «^^ i? is accompanied with some in- each in a boiling concentrated solution a'buk/oli^^^^ "'''''' ""^ ^""^^"'^"^ ^<^i^> produced; while much acetic acid is itfilThpn^^^^^^ is immediately a compound of arsenious acid and oxyde of cooner n « n *^•' °^'^'"^'^' ^^^'^'^ ^o bj composed by sulphuric acid, no aceUc o^r is exhaied Nr."^/"-''"'' ' f'"<^e when de- in?, by exposure to air, or b^ being heatS in water but f^tt K "i"'. -^'^^ ^^ ^'7- liquor from which it was precipitated it soon rh^nlii •» ,' ^ ^^ '*°*^^*^ *" ^he acidulous gation, and forms a new denSin \ip X^^^^ its color, as well as its state of a^^re- As fine a color is produced 'bTrbumbndu'n'fivlrsrr ^^^^" ^ow^er. end of several hours by mixin ^"^ » prl^^ci::^^^^^^ be corrected by ap, acid, the stain is best counteracted bv the annl.vJ. "r ^''''^'' *^^«^*^ '« reddened by an Silk colors are injured by soapror alkaline'^^at p?. 1 ''^''' «*' ^'""^onia. If delicate colorless vinegar of moderate force An rrt,?v. ' ' ^^ r^*"' "^"^^ ^« ^^^ted with made as follows : - Take f"ller%e;rth^ freest VoTnT^^^^^ '""""^"^ ^''^'' «P«^« « water ; mix with half a pound of threa th%o ' eLri^h 2^ matter by elulrialion with «oap and eight yolks of eggs well beafu , whh Zf^' ""^^ T""^ ""^ ^«^«' «« »«"<^h whole must be carefully triturated upon a'poZy.^ ih T."'' ^'^i ^""'^^^ «^-?^^^- The same manner as colors are ground, mix"n^ in Sad Inl ^k' ^^^ '"^^ "^'^^ *^^ ^^«^P ''^ the ly beat together. Incorporate neirthe foft earfh k/ . ^T ^"^ '^^ ^^-"«" P^^^i««^ paste be formed, which should be made into hTnln ^ 5^°''' ?^^'^^'' *'" ^ ""^^orm thick out to dry. A little of this determent beTn° tr! a ""1^^^ ^[^ convenient size, and laid with water, and applied to the stafn^wHl remove 7t " p'^'i / ^""'' '"''^*^ ^"^° ^ ^^^^^^ through Its own bulk of water, appli^^to thesnot. n,hhT^1. •'■^'" ^' ^« ^'^ ^'^^^^^ till they disappear, after which the stuff is tote w«?h 1 "^k" 'T ^^"°^ ^^^^ the hands substance for removing stains on woollen clothes "* ""''^ '"" ^^'"^- ^^ ^« ^^e best or a tXot:11.^ir^^^^^^^^^^^^^ "Pon the dry clothes with a sponge with some plastic clay rediced lo^'.wder WiE Jh^r'" ''-^'"""'^'^ formed round the stain, as large a. i/ie part mn/C i ''u^'u"^^"^*^"* * *^^«"d would be Oxalic acid may be applied in nowul Tri ?i^^"^^ "^'^^ *^^ turpentine, well rubbed on, a'nd ihelZ.'^^Tor::^^^^^^^^^ ^'^^--^y -oi^tened with watei, Sulphurous acid is best ffpnpmt*..! «» »k ^aier. stained, they should be susSdt' a' oV"di„TrvTmilr""\"- J' ^^^ ^'«^^- ^^ -"- the sulphur may be burned under the w de e7d of 1"^'"?, "^^'?^''' ^"^ ^"«'"^ ^^^ms, upper orifice is applied near the cloth ^ ^ '"^" ^^'^ °' P^P^'' ^""nel, whose Manipulations of the sccmrer —ThPQP /.nn.- ♦ « . • water, or in soap-water. The cloth must hf' f ' '" "^l'^'"" ^^^ ^^"^^^^^ '" clear soft rubbed with the appropriate reageitraLve "d'es ritf '?? °"k " ^^^'''"^ ho^r^.^nl hard brush. The application of a redStTon a HUle wl'^'ilf' ^"^ * ?P^"^« «^ « ^mall volatilizes the greasy matter out of it Stl'n" of n t^h t{ ^i!" * moistened spot often become dry. must first be softened with a ifttt K' uT' T'\ P*''?*' ^^^'^^^ »^«^« with the powder of the scouring ball Whe, p l\ \^ u"" ""^ ^^'■^' *"^ ^hen treated be restored by applying the fiterld m^cuLe of tm f^^^^^^^^ 'f^" ^^""^ «'^^'' ^^ "^^^ a frame to dry. Ribbo^ns are glossed with¥nglasfTpT'^"'' ' stretching it „poi SCR W' M "■ *^'^ ^^""^ ^""" cleane l! ^ ^'"^"" J"''^ ^« "^^^ ^o brighten Taper wckkI sc/ewJhHron.f;:^, fi^dtoS'- l;'^', ^--'^/— i»^-v/a..«r^. description, and for stoves grate, etc ^^ ^""^ "^'^"^^ ^«'' machinery of every SSr L"'te^:^;;t^^^^^ «- cabinetwork, making machine, a pLe suffictnrt" fTrmtscretT'^'l' '^^ '"^''.^"^^^ '"*" «>« '^^^rew- is to say, the portion which forms the head if. '"S'^^' '^""^^ "P ^"^ ^^a^ed, that ♦' blank" is dropped into a receXlf Llow ' n P •'''''*^ '"*" ^'^^P^ ^"'^ the now caUed and smoothing the counteS which i7npr?P^^^^^^ 2 consists in flatteaiing the head clams and having a cutLr revoTv^nl in ^tJlT''^ ^^ '^l "^'*"'^" ^^'"^ ''^I^ ''" both " blank" is placecl in a pair of nTpner? whirhT' """"^ u?"^^^'" *'"^'"^- ^' ««"i"^: th* action ; the head is pre^seS ISt a smaU rplir''^''-""^"''""'' ^^ "^'^^"=' "^ « ^^^o^ i' against a small revolving circular saw, and the slit made 1238 1239 1240 4. Threading is effected by the " blank" being introduced into a pair of clams which is attached to a spindle, the back part of which is cut with a wonn or thread corresponding to that of the screw to be cut, and which propels forward the clams and the " blank" against small toothed cutters, which groove out the thread ; three runnings down are suf- ficient to complete the manufacture of an ordinary sized screw. The diflference in the fineness of the threads arises from the shape of the cutters. SEAL ENGRAVING. Tlie art of engraving genis is one of extreme nicety. The stone having received its desired form from the lapidary, the engraver fixes it by cement to the end of a wooden handle, and then draws the outline of his subject with a brass needle or a diamond, upon its smooth surface. FHg. 1237. represents the whole of the seal engraver's lathe. It consists of a table on which is fixed the mill, a small horizontal cylinder of steel, into one of whose extremi- ties the tool is inserted, and which is made to revolve by the usual fly-wlieel, driven by a treddle. Tlie tools that may be fitted to the mill-cylinder, are the following : Jig. 1238. a hollow cylinder, for describing circles, and for boring; Jig. 1239. a knobbed tool, or rod terminated by a small ball ; Jig. 1240. a stem terminated with a cutting disc, whose edge may be either rounded, square, or sharp ; being in the last case called a saw. Having fixed the tool best adapted to his style of work in the mill, the artist applies to its cutting point, or edge, some diamond powder, mixed up with olive oil ; and turn- ing the wheel, he holds the stone against the tool, so as to produce the wished-for delinea- tion and erosion. A similar apparatus is used for engraving on glass. In order to give the highest degree of polish to the engraving, tools of boxwood, pewter, or copper, bedaubed with moistened tripoli or rotten stone, and lastly, a brush, are f,istened to the mill. These are worked Like the above steel instruments. Modern engravings on precious stones, have not in general the same fine polish as the ancient The article Gems, in Bees' Cyclopcedia, contains a variety of valuable information on tliia eubject, equally interesting to the artist and the scholar. SEAL FISHERY. The seal fishery of Newfoundland has now become the most important part of the trade of that colony. Although not so extensive a staple, or so generally followed as the cod fishery, yet when the capital and time employed, and the almost certain and immediate return for investment, are taken into consideration, it is by far the most profitable part of the business of that colony, or perhaps of any otUer part of the British empire. A quarter of a century ago, there were only about 50 vessels, varying from 30 to 60 tons burthen, engaged in this branch of trade ; but within that period it has been gradu- ally increasing. In the year 1860, the outfit for this fishery from Newfoundland consisted of 229 vessels, of 20,581 tons, employing 7,919 men. The number oi seals taken was 440,828. According to the custom-house returns for that year, the total value of skins and oil produced from the sale amounted to 298,796/. In the present year, 1852, the outfit consisted of 3G7 vessels, of 35,760 tons, employing about 13,000 men. The returns and value of this year's fishery have not yet been ascertained. Although it was a disastrous season, in respect to loss of vessels, yet the catch of seals upon the whole was above an average one, there being from half to three-quarters of a millioa seals captured. The vessels engaged in this business are from 75 to 200 tons burthen. Tliose lately added to the sailing fleet, and which are now considered of the most suitable sizes, range from 130 to 160 tons. Vessels of this size carry from 40 to 50 men. The season of embarking for the voyage is from the 1st to the 15th of March. The voyage seldom exceeds two months, and is often performed in two or three weeks. Several vessels make two voyages in the season, and some perform the third voyage within the space of two months and a half The seals frequenting the coast of Newfoundland are supposed to whelp their young in the months of January and February ; this they do upon pans and fields of ice, on the coast, and to the northward of Labrador. This ice, or the whelping ice, as it is termed, from the currents and prevailing northerly and north-east winds, trends towanla h 690 SEAL FISHERY. SEALING-WAX. the east and north-east coast of Newfoundland, and is alwavs in Ko a.««j «« -««« —a of the coast after the middle of March, before Xhlime'TSy^u^g'^L^^^ Z ^^o^n"^ to be profitable. The young seal does not take to the water until his three month! o^d. They are often discovered in such numbers within a day" s^l of the porTthaJ tTr 7 ^:ru^7lJ'^} '."^"^ *« ^^^ » ^««««1 ^it»» the pelt,, Xrconlist of^he Ikfn novIt'"stftoi';L''^^ 'th'" off while the animal ?s wirmrL'^'^l^lLXo? f-V / !V **° ^°® **^- ^^'^ y°""? seals are accompanied by the old ones which take to the water on the approach of danger. When the ice is jammed and the;e is no open water, large numbers of the old seals are shot The youngTaU are e^ilv VZ 1^:1' IZfLVJtJT'iT^ ' slight stroke of a bat o^ V^ead rea'^Vd'te nnAlrV T^K P!i ^'^^^ *^^'^" °° ^^^^' suflScjent time is aUowed for them to cool ?he market at%t'joW° ''7'.t *^^V".^""^ ^^/^^ ^-^<^' ^nd in this state th"yre^h r^Lh ^tllf T ^ . " ^, *""* ""i^^f P^''* '° ^^^ •«^*°^- Five-sevenths of the whole catch W fhl •• "^.f " « °^f ket. A thousand seals are considered as a remuneratirnumber 6 000 IT'"'^ "• K^' ^"''"^' ^^'""^ ^'^^ "P^^^^d^ «f 3,000, many with IS^and h^i.L i '"""^ "^"^^ ^, "'^^y ^ '^'^«^' S'^^^' *°^ »'000- Seals were formerly soM by tale ; they are now all sold by weight,-that is, so much per cwt. for fat anTsWa cond . P7*r^ 'P'"^"' '^P'"^"^ ^••^ '^« *^««d *°d harp seal. The bu k of the ^atch consists of the young hood and harp in nearly equal proportions, lie be. and most productive seal taken is the young harp. There are generally four different a uaimes at?p^^^;^^''^^'^?f"^^r*^"y°"°^ harp, young ho^, old harp anri^dlarr the It V. ^V^^u "i^ ^^°«<^)'.«"J ^e old hood. There is a difference of 2? per cw in the value of each denomination. P * *° from th^/'irfhh ^^''' ^^"ff and weighing is the skimming, or separating the fat irom the skip ; this is speedily done, for an expert skinner will skin from 300 to 400 young pelts in a day. After being dry-salted in bulk for about a month ^he skins are sufficiently cured for shipment the chief market for them being Grelt Brit^ m fet is then cut up and put into the seal- vats. ^"lam. ine The seal-vat consists of what are termed the crib and pan. The crib is a strong, wooden erection, from 20 to 30 feet square, and 20 to 25 feet q height It is firmlv secured with iron camps, and the interstices between the upright posts are filled S tont ' Th! :T ^ Pt" ^' .^^ " ^*^^°^ *'^^^^ fl^"-' capable^of^usLinTng 300 or 4oS tons. The crib stands in a strong wooden pan 3 or 4 feet larger than the square of thp crib, so as to catch all the drippings. The^^pan is about 3 fee? deep and tiSuyc^^^^^^^^ A small quan.t;jr of water is kept on the bottom of the pan, for the douT purZe of fnr^^ '.r^ '^ '^'^ ^^ ^ ^"^^' ^^ ^°^ P""^^'^"^ it fro^ the bl<^ and^anTother ^ ifiln^"r- °^ '7'?^' ^'^'''^- ^^ '^^^^^^^ ^y *W« P'«^««« i« aU cold-drawn no Whtfl ^'^^\''^PP}'^^ ^» any way, which accounts fir the unpleasant smell of TeaUa When the vats begin to run, the oil drops from the crib upon the water in he p^ whlh 5 ««^»"1"^^*"' ^* ''-"^^^^ °^' ^°^ '^^^y f«^ shipment The first runnhfc' which IS caused by compression from its own weight, begins about the 10th of May ^ni in T^T' *^ ^'^\^ ^>\^ '' *"^"^"^ P""^' ''^^^^^ fro«^ two to three months, S from 60 to 70 per cent, of the quantity is drawn off, according to the season or in fhTsTs'noT «?f ?/ ^""t '^ '^ °^^ ''^^ ^"' ^^ P"^ ^^*« '^' ^**«- ^'o™ beingToughe ° this IS not acted upon by compression, nor does it yield its oil until decomposition takes from he vats is much freer from smeU than tfe latter!^ As decomposition takes dE darketanH rf ' *" «traw becoming every day, as the season advances, darker a?d slackens^t Cn K^ """""'^ ^°^ ^''''^' "°*^^ '' ^"^^^^^ ^""^ ^'"^^^ «il- A« this running slackens, it then becomes necessary to turn over what remains in the vats. The crib being generally divided into nine apartments or pounds, this operation is performed by first emptying one of the pounds, and dispersing the contents over the others aTd then filling and emptying them alternately until the entire residue, by this time a comDlete S,t1n'//"'^^"'"""' -^^ *""^«^ o^er By this process a furthe; rLning rbrown oTi! ?h. "k i ^^ '"""^'"f *'^*^^" ^°*"^ ^^^^ «"t in large iron poU, which duHng the whole season are kept in pretty constant requisition for boiling out the cutt'^^s and clippings of the skinning and other parts^f the pelts, whifh H is not fS advisable to put into the vats. The produce of this, and t^he remains of the vats are what IS termed the boiled seal oil. These operations occupy about six mon hs and ter^ mmate towards the end of September. ^^ "iuuuis, ana ter- v^f^'^jiw^W "'''''*^' ?? '^"^^' ^"S"«t, and September, the smell and effluvia from the vats and boiling operation are almost insufferable. The healthy situation of St John's fn>m Its proximi y to the sea, and the high and frequent lo J winds, is doub tles^ the cause of preventing much sickness at this season of the year. I have never known any d^se or epidemic attributable to such a cause. The m^n more immediately employed about the seal-vats have a healthy and vigorous appearance. employed Some improvement has taken place since the great fire of 1846, when all the seal-yata 691 in the town were destroyed. Many of the manufacturers have erected their new vats on the south or opposite side of the harbour ; but there still remains suflicient vestiges of the seal trade to cause a summer residence in the town of St. John's anything but desirable. Even the country for several miles around St John's affords no protection from these horrible stenches. The animal remains from the vats, and the offal from the codfish, are found to be such a valuable manure, that they are readily purchased by the farmers in the neighbourhood ; and from whatever quarter the wind blows, the pedestrian in his rural walk has little chance of breathing a genial atmosphere. After a year's residence in Newfoundland, the attention of the author was turned to some mode of improving the manufacture of the seal oil. The result of several exj>eri- meuts upon the different qualities of seal's fat satisfied him that the whole produce of the fishery, if taken while the material is fresh, as it generally arrives in the market, and subjected to a process of artificial heat, was capable of j'ielding, not only a uniform quality of oil, but the oil so produced was much better in quality than the best prepared by the old process, and free from the unpleasant smell common to all seal oil. His subsequent experiments resulted in the invention of a steam apparatus for rendering seal and other oils, which has been found to answer an admirable purpose, and for which he has received letters-patent under the Great Seal of the Island of Newfoundland, securing to him the right of his invention for fourteen years. The advantage of this process must be manifest, when it is understood that twelve hours suffice to render the oil, which by the old process requires about six months ; that a uniform quality of oil is produced superior to the best pale by the old process, and free from smell ; that a considerable per-centage is saved in the yield, and what is termed pale seal, produced from the old as well as from the young seal. (The sample herewith sent Dr. Ure is from the old hood seal.) Besides, if this process were universally adopted, the manufacturing season woujd cease by the 31st of May, and the community would be saved from the annoyance attending the old process. The chief market for seal oil and skins has hitherto been Great Britain and Ireland : a few cargoes occasionally go to the continental cities. This year, for the first time, a new- market for seal oil has been opened in the United States, owing to the greatly increased consumption of oil in that country, together with the failure of their whale fishery. Upwards of 2000 tons of this year's produce have already been shipped to that country. The latter shipments, however, have not realised to the shippers the prices of the first, from the fact that, upon the trial of this oil, although it was found to be valuable for its combustible qualities, yet in a hot climate it was altogether unfit for domestic purposes, on account of its singularly offensive smell. In the United States the great consumption of oil is for domestic purposes ; the chief dties only as yet being lighted with gas, and that but partially, from their constant in- crease. Candles, unless of the most expensive kind, will not suit that climate, particu- larly in the summer season ; and hence oil and camphene, where gas is not used, are the chief ingredients for lamps. All animal oils used in that country, whether of sperm, right whales, or lard, are rendered by artificial heat, and in consequence free from the un- pleasant smell of our cold-drawn seal oil From his having exhibited samples of his oil in America, the subscriber has fully ascertained that, on account of its yielding so brilliant a light, and producing no offensive smell, it will command a much higher price than the best pale, prepared by the cold- drawn process. — 8. G. Archibald, St. John's^ Newfoundland. SEALING-WAX.— (Circa cacA^°y. li «- cinnabar, b,af LigtirhlaTf-tlr^/n't IsTuoltlsV^^r"''^ * "^- -<""«»'y- -P" oaTt'^^enZe ''""'"'" '"'P'"""'' * ""• *'"-'^'=- « "^ ""ophooj, Ump-bUck, and 4tUarn,r;net°an^Toft"uVnre^'^"-'^ ^* "^- "''"P^-^' * - '""S'' ear^hti^^rL^er Jrr '"''"'''°^' '* ""• **"•■-• '* '- •"o™ English ear^hl^^ii^^xtaglr rawr'"'- ' °^'- ^'"'"■"^ " ""■ «>'''?■-?. H <>- EngU.h 4;«~prdIhTlfr„"a^r^^^^ ^-^"-'-^ ' o^-O-wn earth. *o. ».i^::;fbfi::^4:::iaLTre *"'""''''''' ' "^ *■«' '"'"'■''"=■ ^ <»• ""opw. i <.. ye.t;Toiroirt"e,!::p^::iritc ^'"''-'^ '* »^- '"'»p'-<'"^- * - >^-8'» ch|r;:d,ttr^rgoTra.''j;^VKf"t%tt^- '-^"-'^ ^ - -•"p-'-^- ^ »- brot??tri^'et'':Sunu?p:X'^"-^"^ " »"-'' of S-"- '-^Sold. ioz. ihf^n'l^^'^^-^' '^^^TP""'^^ ^ ^«"«^^' according to the author of the artirlo ^.;-„ • the Dictionnaire Technologique .-—Chloride of sodium OKn m j ? ^<'^»'*<^*. >" 0-35 ; sulphate of magnesia 0-58 • carbonatprnf^mo ' a^ ' ^'^^^"^^ ""^ magnesium, limo, 001? water, 96^ri00 paVtT Se^^^^^^^^^ LT "^ '°'^°""' '•'' ' ^"^P^^^« ^^ bea-water, distillation of. ITiree of TTpr Mai'oo^^'.. ^i.- a^ Fitzroy. the Plumper, l^ cl^^JeJ^LuoTi:^^^^^^ ?^^^P*r Crawcroft, have been furnished with the Government di^trnfr:! ' ,9«°^°^ander constructed by Mr. Grant: other gaUeys of t^,e s™me kind I^! ^ ^""^ ^^^''"^ ^^"^y* facture for the largest class of ^essL. The iSunUess 1496 ?on" T' t °^ °^"""- 1.556 tons, and the Encounter, 906 tons, all Lw shins on tL«^' ^ Termagant, ordered to have first class machines of the aW descriDt^on L I^ .P"°^'P'«' ^^ made smce the introduction of the galleys into the nfv/l P^^J" I *^® ""P'-ovements water obtained by the distillation o^f saTwater durin^^^^^^^ quanity of fresh the fires alight in the gallev for the purDoses ofT?- P-n"*^ '^ l^ required to keep each individual on boarl the^veLels wi?h Te ' ^^^^^^ «" ^^e average, suppl^ latter kind of water continues to be preferred^for ^^^^^^ "^^'^ ^^y ' ^ho water usually supplied to the shins • it casses mnlT . ¥ r^ ^"V""^ purposes to the water tanks^it t£e same ter^Sure ^^ th^r^ *^^ condenser into the becomes perfectly aeraJ^^loX aWether^L vT^^ '^''^°- ^° *^^«^ *^»^^« ^^ water in the course of a few hfurs without tJP-^^7"^^^^^ *« *" ^»«tilled mechanical arrangement, br^eZnle fact of It ^T-"^ ^^ "^^"'^^^ preparation or motion of the shiS when'at^se" Tsties of vert LprlT '"P";'-"^ *^ '^' ^"^^ ^^ *»»« have, however, been made, and are still i^U^f^^ ^u^ '?P°'*^"^ ^^P""'^^"*^ Captain Yat.; bearing the f^V ^ Z^S{^^Z,''c^t KhiS, l^' SEWING BY MACHINERY. 693 Mr. Cross, with the view of imparting at the moment of distillation the oxygen of which the water is deprived in the process, and giving to it that briskness which is found in epring water This is effected by passing a proportionate current of electricity through the oarticles of water by means of an extremely simple and self-acting apparatus. The results ()f tlie experiments made have been highly satisfactory. The only point to be determined is, whether any artificial means, either chemical or mechanical, are required for aerated distilled water on board ship, as it is found that such water becomes sufficiently aerated in a few hours by the motion imparted to it by the ship; but if the water is required for immediate use, Mr. Cross's application produces the object desired most effectually. SEGGAR, or SAGGER, is the cylindric or oval case of fire-clay, in which fine stoneware is enclosed while being baked in the kiln. SELENIUM, from IieXijvT}, the moon, is a metalloid principle, discovered by Berze- lius, in 1817. It occurs sparingly in combination with several metals, as lead, cobalt, copper, and quicksilver, in the Harz, at Tilkerode ; with copper and silver (Eukairite) in Sweden, with tellurium and bismuth in Norway, with tellurium and gold in Siebenbiirgen ; in several copper and iron pyrites, and with sulphur in the volcanic pro- ducts of the Lipari Islands, Selenium has been found likewise in a red sediment which forms upon the bottoms of the lead chambers in which oil of vitriol has been made from a peculiar pyrites, or pyritous sulphur. The extraction of selenium from that deposit is a very complex process. Selenium, after being fused and slowly cooled, appears of a bluish-gray colour, with a f listening surface ; but it is reddish brown, and of metallic lustre when quickly cooled. t is brittle, not very hard, and has little tendency to assume the crystalline state. Selenium is dark-red in powder, and transparent, with a ruby cast, in thin scales. Its specific gravity is 4'30. It softens at the temperature of 176° P., is of a pasty con- sistence at 212°, becomes liquid at a somewhat higher heat, forming in close vessels dark- yellow vapours, which condense into black drops; but in the air, the fumes have a dn- nabar-red colour. This singular substance, apparently intermediate in its constitution between sulphur and metals, has not hitherto been applied to any use in the aits. SELF-ACTING MACHINES. See Machines. SELTZER WATER. See Soda-water, and Watees, Minkeal. SEMOULE. The name given in France, and used in. this country, to denote the large hard grains of wheat flour retained in the bolting machine after the fine flour has been passed through its meshes. The best semoule is obtained from the wheat of the southern parts of Europe. With the semoule, the fine white Parisian bread called ffruau is baked. Skilful millers contrive to produce a great proportion of semoule from the large -grained wiieat of Naples and Odessa. SEPIA, is a pigment prepared rrom a black juice secreted by certain glands of the cuttle-fish, which the animal ejects to darken the water when it is pursued. One part of it is capable of making 1000 parts of water nearly opaque. All the varieties of thia mollusca secrete the same juice; but the Sepia officinalis, the Sepia ioligo, and the Sepia tunicata, are chiefly sought after for making the pigment. " The first, which occurs abun- dantly in the Mediterranean, affords most color ; the sac containing it being extracted the juice is to be dried as quickly as possible, because it runs rapidly into putrefaction! Though insoluble in water, it is extremely diffusible through it, and is very slowly de- posited. Caustic alkalis dissolve the sepia, and turn it brown ; but in proportion as the alkali becomes carbonated by exposure to air, the sepia falls to the bottom of the vesseL Chlorine blanches it slowly. It consists of carbon in an extremely divided state alons with albumine, gelatine, and phosphate of lime. * The dried native sepia is prepared for the painter, by first triturating it with a little caustic ley, then adding more ley, boiling the liquid for half an hour, filtering next saturating the alkali with an acid, separating the precipitate, washing it with water, and ^'^oi^J.i^i??**' ^^1^* ^^?^^^ ^^^^' ^^^ pigment is of a brown color, and a fine grain. SEPIARIA, called anciently Indus Hehnantii, (the quoits of Van Helmont, from their form,) are lenticular concretions of clay ironstone, intersected by veins of calc-spar which, when calcined, and ground to powder, form an excellent hydraulic cement. See MoktI^ HrDRAULic. ■^ SERPENTINE, is a mineral of the magnesian family, of a green color : it is scratched by calcareous spar, is sectile, tough, and therefore easily cut into ornamental forms. It o«curs in Unst and Fetlar,in Shetland; at Portsoy, in Banffshire; in Cornwall; and the Isle of Holyhead. The floors of bakers' ovens are advantageously laid with slabs of terpentine. SEWING BY MACHINERY. The Wilson machine is in our opinion a great triumph of American genius ; it is no larger than a neat small work-box, very portable 694 SHAGREEN. Ai «nd convenient, and we have seen fine shirt bosoms and collars stitched by it in a more perfect and accurate niauner than any we have ever seen done bj hand-work me™ we first noticed How's Sewing-machmerj, in 1847, there was not a solitary machine of the kind m active operation, m our whole country, if in the world There are now wa beheve. about 500 m opeijtion. and we have bei, told by Mr Wilson thaUheordera for his machines cannot be supplied fast enouffh There arp «f r^ri-l^f II a i machines about finished at the Company's ^oT-WhZL wtLrZ Co wtf town, Connecticut, and these are all engaged *^°eeier, wiiaon, and Co.. Water- asrcLTreToSntyr': To^w'^tttillt^^^ ^« -^ .titching by one of Wi Jn's little machines L' algl tu^. 'Th^tLe'^^^^^^^^^ wives tailors, and sempstresses of every description, il of incalculable TrnpoHance for i? T^Vlr *^'" ■?^.iZ^^^ ^^^^ ^>*"°'^«" *« «*»^^^ ^^^SB, during the Ze whTch u'ed to be taken up with dull seam-sewing. Youne ladies will have mopp Hmo +r!i * ! ornamental work, (it would be bette°r for the^i afu? They Sfd more o^U) Ind fln^He: m which here are a number of children, which require a continual st tch ^g in ^^^^^ machre" "^ ""^ '°'""^ ''^^ "'^''' ^^" ^'' ^ ^1^«*«^ by the improv^ei s^wbg^ ?S A p Rir^i?''''JWl ^'^'^^^ * perpendicular or slightly inclined pit. ^•ff 7? 1*, ^^J^^Sriny Fr. and Germ.) The true oriental shagreen is essentiallv different from all modifications of leather and parchment. It approachertLlaUer som/ what, indeed m its nature, since it consists of a dried skin, not combined wfih an tannTne or foreign njatter whatever. Its distinguishing character stic is havTn- iTe 47n or S side covered over with small rough round specks or granulations. " .hfii'/'^^^K ^T/^^ skins of horses, wild asses, and camels ; of strips cut alon- the Sn nV ir It- "?^^»,^Tl'^« ^*i« tail, apparently because this st^on^; and Uncker^'por! Uon of the skm IS best adapted to the operations about to be described. These fineti mrc to be steeped in water l 11 the epidermis becomes loose, and the hairs easi y come away by the roots ; after which they are to be stretched upon^ board/anddrested with the f ffS ?'^^ -'^■^."'^'- ?^?"y "™"^* b^^^Pt continually moist, and extend;rbvcorf8 attached to their edges, with the flesh side uppermost upon the board. Each strin now resembles a wet bladder, and is to be stretched in an open square woS;n frame bv meanT of strings tied to its edges, till it be as smooth and tense as a drurhead For thiTnur pose it must be moistened and extended from time to time in the frame ^ l,;n^V**i? *'^,^*^»^f °^ ^^^ "^""'^^ ^^"P «^ skin must next be sprinkled over with a wUh ?hfrf t *=^"^.,f ^«^'«> ^'-'hich are to be forced into its surface^Xr by tramping ThX^X T^i:^ A kT^^" P'Tv? P'"^" ^^ ^^^' «^ ^'^^' thick stuff- being^aid u^I {^«T^ ; c J • tf **f b^'r? P'-?^ai>Iy to the Chenapodium album. They are lenticXr hard of a shining black color, farinaceous within, about the size of poppy seed and «« sometimes used to represent the eyes in wax fi^-ures ' ^K^Ilf f •''r' ^'PP'^1° dry in the shade, with the "seeds indented into its surface • after ?hl nntVl 'm1 kTk^^'^ ^y '^^^^"» ''> ^"^ b^^ting upon its other s de with a 's?k? and number ^fre^seeS. '""'' **"' ^^"^' "^^' ^"^" ^°"^- corresponding toVe st^ In order to make the next process intelligible, we must advert tn »n«fi,o, i .nd well-known operation. When we make' impr^siorfn fin^^rlreSt: w^Tft p::iinr..fw\^r^;T.isrr2^^^^^^^^ The strip of skin is stretched in an incUned plane, witn its upper ed<'e attached to hook«- semitr^^' T 'w ^'^ "''' \^^="'^^' ^" ^"^•^'^ P^^^tion it is'thinn^ 'rwith a prop5 semi-lunar knife, but not so much as to touch the bottom of the seed-nits orienrrS/ oLTTe'TV: XT ?d T '' l'^".nV° ^"^"' -^ thVKco'L'To^^^^^^^^^^ over the surface which had been shaved. The swelling is completed bv steenine the aStherdy"^:" '''"'"" °^^^"^''^'^' "'^^^ In the East the following processes arc pursued. Entirely white shaereen is obtainpd kev' wheaTlnd lfte"/^r " ''''''r ^'k^^""' ^«^^""^" '' -'^h the dough^LadV^^^^^^^^^ «^L Si^ s?"^^ * ^'°*^ washing this away with a solution of alum. The strins are TaTer turlrwithTbTun'JrT' '' ?T'^' *!^^^^ '•'^•^^^^' ^^^ --^^ <^-''-" ^^ ho water curried with a blunt knife, and afterwards dried. They are died red with decoc l^on oHMrsTl Lt'r? ^"^,^r" -ith fine copper filings Ld sal ammonracthe^ mnlfJ inf/ if fif^i ^PPl^^d, then the filings being strewed upon the skin, which must be rolled up and loaded with weights for some time ; blue is given with indigo auiJk. hme, soda, and honey j and black, with gaUs and copperas. ° * ^ fcjHEATHING OF SHU>S. 595 SHALE, or SLATE- CLAY, is an important stratiform member of the coal- measures. See PiTcoAL. SHAMOY LEATHER See Leather. * SHAWL MANUFACTURE. Shawls were originally woven in the heart of India, from the fine silky wool of the Thibet goat ; and the most precious of them still come from Cashmere. The wool of which these articles are manufactured consists of two dis- tinct sorts, called wool and kemp. The wool is beautifully rich and soft to the touch, and is probably superior in this respect to the finest continental lamb's wool, and equal in richness to the Thibet wool It is also divisible into qualities. The kemp presents the appearance of a coarse rough hair, such as is avoided by the manufacturer in all pur- chases of wools, deteriorating as it does the appearance of even common fabrics by its inferiority and harshness. The two wools as shorn from the goat are closely intermingled, and present the ap- pearance of a coarse hairy wool of a very low character, but a minute inspection shows that part of it is of a very fine quality. In order to separate this fine quality from the coarse, it is necessary to do so fibre by fibre, and this has to be effected entirely by hand, no machinery having as yet been applied to this purpose. The process is both difficult and tedious, one person not being able to separate more than half an ounce in twelve hours. After the separation of the qualities it is desirable further to divide it, in order to make a warp yarn for fabrics like the shawls ; but this was impossible in the present instance, owing to the small quantity produced, otherwise the fabric would have been much finer. In the dresses this result has been achieved, because the warp is of silk, and the quantity required for the weft was therefore not so great in proportion. The specimen of coarse cloth in the Great Exhibition was entirely manufactured of coarse hairs or kemp after it was assorted from the finer material of the wool In a ge- neral way this is considered worthless. SHEATHING OF SHIPS. For this purpose many different metals and metalUc alloys have been lately proposed. From a train of researches which I made for an eminent copper company, a few years ago, upon various specimens of sheathing which had been exposed upon ships during many voyages, it appeared that copper containing a minute, but definite, proportion of tin, was by far the most durable. The process of coppering vessels, which has of late years been generally adopted, in order to protect their bottoms from the injurious effects of insects m hot countries, and prevent the adherence of barnacles, *»y the same invention ks that which the plfintTclaTmed M iWs"^^^^^^^^ ^'a: *^« y^"- sheat?iing (the si'arhin'^ ♦lloJ !; * ^ consists chiefly of zmc and copper. The compound must be heated and in ^t state rolled; 100 parts of copper anS 80 of zinc afford a ^rd com posit bn^^^^ ^e proportions may be varied, or other metallic substances added.^videTthe proiertv of bearing the mechanical process, when added, is not destroyed." ^Ev dence was Sfven S; th:n te'r Aprif mt wi:' «^«V'^Sr^ ^^^'^ °^^*^"^^ sheathing m^ufXe" Sll^oi * ^ ' ^.' ^^ "^^de from the specificat on in CoUins's patent alone and several witnesses were also called to prove, on their behalf, that a comp^ositioo or^^^^^ The Lord Chief Justice, before proceeding to charge the iurr told them fliAf if tt.^ ^o'thffr"', '[uT'"^ ""^ "'■"^^ °f «"= "idenceWoie^he should wh to t^ ttat t,i,?^„^/i^*' PTrr ' *"" "• """"B ''=«'» the eridence, they did not r^'re thel w™1l T" ''^^'»•.''^ <'\«^^ P"<»ed to call their attention to the points on whWk the ?nm^n?r P f J^as sufficiently plain and intelligible to enable other peVsons to make nr^ni^P "lu ^'"' ^^'""^ f.^ P**^"' ^^d been granted. His Lordship also Tve h T^ Son w.;Tn A^ "'•K '^v^^ l^^ ^"^^'"^ ^" ^'^^ ^^^^«' that the nature of tL p?aS's i^v^ «WpT f K f,!''".^^^'^ *^" *'^^" «^ ^^^ patent,-" An improved manuCture of metal gates for sheathmg the bottoms of ships or other such vessels ;" that neXr " Lst selS S^a^comZi •^°'' f ^" r'l'^r^ P^^^ «^ *^« i"^^"*i«°. ^hiih consisted in th^ discovery no morTtir ^v ^^eathmg by which a proper degree of oxidation was obtabed ^3 andXf 'fli • "*-"^ ??^i """^^ ^^ * '^d heat was not claimed as part of the invention SS^i,^^- See Lac, and Sealing-wax. SHOE-BLACKING. Ivory black - - . , Treacle - . . ^ Vinegar - . . " Oil of vitriol - . . Sperm oil . . . * To be mixed in the above order in a mortar Ivory black . ^ ^^-ckir^ (paste). Oil of vitriol - , . Treacle - • - I " Sweet oil - . . * Vinegar . . J J " Sulphate of iron - . " ' Gumarabic - *'»a sometimes confounded ; though the feldspar, which is generally red, is the more abu.i- dant constituent. The Egj'ptian sienite, containing but little hornblende, with a good deal of quartz and mica, approaches most nearly to granite. It is equally metalliferoui with porphyry ; in the island of Cyprus, it is rich in copper ; and in Hungary, it contains many valuable gold and silver mines. Sienite forms a considerable part of the Criffle, a hill in Galloway. It takes its name from the city of -Syene, in the Thebaid, near the cataracts of the Nile, where this rock abounds. It is an excellent building-stone, and was imported in large quantities from Egypt by the Romans, for the architectural and statuary decorations of theii capital. SILESIAN LINENS. The manufacture of linens is carried on in Bohemia, Moravia, Silesia, and Galicia on the largest scale. Of the entire production about five-twelfths are brought into the market, and of this quantity the bulk must be of domestic manufacture, since few great linen manufactories exist in Austria. Among the linen fabrics, table- cloths and napkins, veils, cambrics, dimities, twills, and drills are important articles. Ii^ the next rank we must place the manufacture of thread, especially in Bohemia, Moravia, and Lombardy. The tape manufacture is of less consequence ; and as to the business of dying and printing, that has been almost entirely absorbed by the cotton manufacture, and is now m requisition for thread and handkerchiefs only. As the loss resulting from the processes of weaving, bleaching, ,o ^:^t\, Bonks, who brought some eggs of the silkwormTom C ina or IndiaToS,,!: f" T were encouraged to breed the insect and ■.nli,„iT-. mjia to Constantinople, «ian^ Several' silk man^Jactu'rer^el^et c» "q'nen e eT.S'e ' i^Afh^eSr x/r '" " and Corinth, not only for rearing the worm «pon mulb^rnMeafes bnt for tn-L?^ riches from the trade J^urope Miin siJk goods, and derived great ^^^^^zf^^!^:i.:, ^\rs"etnnd" '»'tv"^ Mopnd-s:^;iL-d^-;xr-^^^^^^^^^ =prst-n-:v^^Xe-ii:a^^^^^^^^^ l^J.1 ,'•^^^^"°"«' '» r''*^"'^ "'^■» -"'" ^^^y of the southern ZyTnces of Fr.n» t^Hr„iyTr^d'"si;i:^bt"^vi^:e'"S^^^^^ •objects to p,ant'^lK;?rtT;VurhMe worms «ade great prosress^duHngThark?ni'rpe;ceft.f a^J"^^^^^^^^ '^''^^ ^^"^h ^'""'^''^ become so considerable in London that !?.[ I ?^^ ^" ^^^9 il had were formed into a public corporat^n So earlv a. Jfi'jT' "^ '^ 'I'lA''^ ^"^"'^ The revocation of the edict of Nantes inUS^cnJr^^A^^' '""^^''•'1 ^?.'^^ ^"••'°"^- the increase of the En-lish .ik trade W til ' ^^'^^^'^^^.^ »" * remarkable manner to SILK MANUFACTURE. 599 afterwards, in the year 1730, the English silk goods bore a higher price in Italy thaa those made by the Italians, according to the testimony of Keysler. Till the year 1826, however, our silk manufactures in general labored under very grievous fiscal burdcRS. Foreign organzine, or twisted raw silk, paid an import duty of 14a. 7|i. per pound ; Raw Bengal silk, 4«. ; and that from other places, 55. 7|rf. Mr. Huskisson introduced a bill at that time, reducing the duty on organzine to 5*., and the duty on other raw silk to 3d. per pound. The total prohibition of the import of French manufactured silks, which gave rise to so much contraband trade, was also converted into a duty of 30 per cent, ad valorem. During the reign of the prohibitory system, when our silk weavers had no variety of patterns to imitate, and no adequate stimulus to excel, on account of the monopoly which they possessed in the home market, the inferiority of their productions was a subject of constant pride and congratulation among the Lyonnais; and accordingly the English could not stand their competition any where. At that time, the disadvantage on English silk goods, compared to French, was estimated in foreign markets at 40 per cent. ; of late years it certainly does not ex- ceed 20, notwithstanding the many peculiar facilities which France enjoys for this her favorite staple. The silkworm, called by entomologists Phaloena bombyx nzon, is, like its kindred species, subject to four metamorphoses. The egg, fostered by the gen.'/U warmth of spring, sends forth a caterpillar, which, in its progressive enlargement, ca&ts its skin either three or four times, according to the variety of the insect. Having acquired its full size in the course of 25 or 30 days, and ceasing to eat during the remainder of its life, it begins to discharge a viscid secretion, in the form c' pulpy twin filaments, from its nose, which harden in the air. These threads are instinctively coiled into an ovoid nest round itself, called a cocoon, which serves as a defence against living enemies and changes of temperature. Here it soon changes into the chrvsalis or nymph state, in which it lies swaddled, as it were, for about 15 or 20 days. Then it bursts its cerements, and comes forth furnished with appropriate wings, antennae, and feet, for living in its new element, the atmosphere. The male and the female moths couple together at this time, and terminate their union by a speedy death, their whole existence being limited to two months. The cocoons are completely formed in the course of three or four days ; the finest being reserved as seed worms. From these cocoons, after an interval of 18 or 20 days, the moth makes its appearance, perforating its tomb by knocking with its head against one end of the cocoon, after softening it with saliva, and thus rendering the filaments more easily torn asunder by its claws. Such moths or aurelias are collected and placed upon a piece of soft cloth, where they couple and lay their eggs. The eggs, or grains, as they are usually termed, are enveloped in a liquid which causes them to adhere to the piece of cloth or paper on which the female lays them. From this glue they are readily freed, by dipping them in cold water, and wiping them dry. They are best preserved in the ovum state at a temperature of about 55° F. If the heat of spring advances rapidly in April, it must not be suffered to act on the eggs, otherwise it might hatch the caterpillars long before the mulberry has sent forth its leaves to nourish them. Another reason for keeping back their incubation is, that they may be hatched together in large broods, and not by small numbers in succession. The eggs are made up into small packets, of an ounce, or somewhat more, which in the south of France are generally attached to the girdles of the women during the day, and placed under their pillows at night. They are, of course, carefully examined from lime to time. In large establishments, they are placed in an appropriate stove-room, where they are exposed to a temperature gradually increased till it reaches the 86th degree of Fahren- heit's scale, which term it must not exceed. Aided by this heat, nature completes her mysterious work of incubation in eight or ten days. The teeming eggs are now covered with a sheet of paper pierced with numerous holes, about one twelfth of an inch in diameter. Through these apertures the new-hatched worms creep upwards instinctively, to get at the tender mulberry leaves strewed over the paper. The nursery where the worms are reared is called by the French a magnanilre ; it ought to be a well-aired chamber, free from damp, excess of cold or heat, rats, and other vermin. It should be ventilated occasionally, to purify the atmosphere from the noisome emanations produced by the excrements of the caterpillars and the decayed caves. The scaffolding of the wicker-work shelves should be substantial ; and they snould be from 15 to 18 inches apart. A separate small apartment should be allotted to the sickly worms. Immediately before each moulting, the appetite of the worms begins to flag ; it ceases altogether at that period of cutaneous metamorphosis, but revives speedily after the skin is fairly cast, because the internal parts of the animal are thereby allowed freely to develop themselves. At the end of the second age, the worms are half an inch long ; and then should be transferred from the small room in which they were first hatched, into the proper apartment where they are to 600 SILK MANUFACTURE. i' ■ :1 !>:. 4i •be brouj,ht to maturity and set to snin their hall« n« «- • ^ ^ abode, t].ey mast be well cleansed froT the litter Ldu^^^^ ^^^ supplied with an abundance of food e^ery six hou s 1 T ^'^^ ""^ ^^^ ^'^^^^' *»« bed, a piece of network being laid over the 4^0^ n l es ZT"'''''' /" l^^^*"^ ^^^" worms will creep up over them • whpn tVo« v P;*^^%«»d covered with leaves, the The litter, as well L [he Sv' ZrZ tl^^L^ transferred in a body upon the'net! .single hUhy one"" AfleTthl rr^^^^^^^^ they are now exceedin^^lv voracioiiQ »nA 1,L ^* t f *^ ^"**^^ ^^^^^s; because diet. The exposure of chloride of limP T.-H t'h- ^' ^"^«^^»^"«Iy stinted in their magnanrere, has been found useful L rnteTactit tlTe tS ^^""''Vl '''' ^'^ ^^ ^^« pears^of an epidemic disease ^on^l^^S^^^ ^^ «nh^^l^ ^^K^ """f "^^^ '" *»•' «'">" in "hf fourth or fifth ."e aereeahlv .„ .k work ,vhieh cons.i.u.es ,he ij7^ Sk fo^e Xg andl^i * r."'' " ""'" ""*" "«'• Jt:rXe'':s■l^ht*'r:h„r r '^ -Vi '°"?^ •■- -^ -^^^^ -* «.n.e out, .he filaments at 0"^ e^5 woS d be cut Slh Yn^l r^', '" ^^ '"'''"^' «' Talue. It is therefore nece««arv to extinlnith ,ki rr r fu '^"* '*"' "'""'«' »" 'heir done either by exposing he~cocoo^"fo 'a ftwd«s to su°n,htf/r'',' "^ ''T' *"''" » OTen, or in the steam of boiling water A W of 202" p' Z '?''""°/ "■'"■ '" » ""o' porpose and it may be best admin^ed b^nginAi^casesS w^h^fr'" ""» into water heated to that pitch i'^""S"»o iin cases njled with the cocoons J^X"»C'a'rhe± l^^^^^^ ^^ -ks from iazardous period in the prSsof breedintfhe w^ms I ». fr.V^^'^";?"'- T*' »»«« for upon the sixth day of the ihirH »"„ -^i .if *"'™«' '» /' "he third and fourth moulting j ..t nothing a. all. On the first dayWe fourth?! n '' "'"" '"°"'-"'' ""^^ '" "^"'^ ounce of eggs will, accordin "to BnnJll ^ ' "'* ™™« proceeding from one «.d a quartfr of llberry lelve^^^ firs.'T ZT,?" "'"!!«' '"^ty-thVee pounds two pounds J and on the sSh dav of h! 1 ^?'^"' "«^' ""y "'" consume forty, dty, devour ng no less than 223 i^uLIf T' i*"^ acquire their maximum vori, SV"' ™ '"^ '-'^ 2"y 0^'-'^ a1e%heXf„L'ri;Xr^:dT"''^ "- JLtte^:^e:3];ii^''97ee5^%r*';xs'mtffrd'J^^^ they produce. general, the more food they consume, the more silk will BulT;i'"fo'u™ X.^'ilZZl't'^'''?-''' I''''' ' ^'^ ^« P^-^ed out of the increasing crop oHeaves til 'the weniith if !'Tf '" l^' ^^^ y^^''' «"d affords an according^to iVs ina.^hud a^d mLe ^f c'-ltfv^^^^^^^^^^^ oTe V"'' ^^',7^^- ^^ ^«^^^«' worth in France about 2Krancs it renuire^^^^^^ ounce of silkworm eggs is 15 cwts. of mulberry leaverXch co.TZ an «vt development into cocoons about reason. One ounS of Ssls calcu ated as ? hlv.'^' '/?"'' ^'' '^'' ^" * ^^^«^*^^« poundsofcocoons,of the v^ueof 1 fr 5^^^^^^ '5 ^'"^""^ ^'^°^ «« t° ^00 About 8 pounds of reeled raw ^Ik wo^fh 18 f^anof' ^*'""^.' ""' ^^5 francs in whole. 100 pounds of cocoons. ' ^'^'' * P^""^' ^^^ ^^lai'^ed from these Jo^'^Sr^;^^^^^^^^^ tram ,s made usually from inferior si^krand irvery .lithifvCi^tS '• "'^^^^^^ ^^^^^^^ > spread more, and cover better in the weft tt^ Zrhn,. ^ '^^"'^ *." ^"""^^^ ^^^^ it may •ilk, which is carded and spun 1 ke Totton Orln^ ' T''''^ °^^^^ ^^'""'^^^ t^^o^^eJ to 30 twin filaments of the worm • the^rmePrr'"^ ^""^ ''vf^^ '"^^ ^^^^'^'^ ^''O'" 3 filaments being fipst twis ed Tn one direction Id ff''"' * ^""i*^" ^^^^^' *^« component the latter receives merira sULsTng^t^i^^^^ the compound thread in theop^c^ite, ishes in thickness and slren-th from Ihi ^ ^^9 1""'" ^^^""^"t gradually dimin* begins its work in a state 7v^or Tthl J«t '%*'^ the cocoon, where the animal biJity and exhaustion Tbecau.e f cin receivp n^'f ""^T " ^^'^"^ ^^> ^" * ^^^ate of de- to spin by spouting forth iSslk^ubstinceTh/w' I"^^ '^' "^°'"""' ^^ ^'^ »>^Si»««8 attenuation, and introduces tbe^lrnJ^^elt^^f^te^rorr^^^^^^^^ SILK MANUFACTURE. 601 Imnination of others. The quality of raw silk depends, therefore, very much upon the skill and care bestowed upon its filature. The soi^lest and purest water should be used in the cocoon kettle. The quality of the raw silk is determined by first winding off 400 ells of it, equal to 475 metres, round a drum one ell in circumference, and then weighing that length* The weight is expressed in grains, 24 of which constitute one denier ; 24 deniers con- stitute one ounce; and 16 ounces make one pound, poids de inarc. This is the Lyons rule for valuing silk. The weight of a thread of raw silk 400 ells long, is two grains and « half, when five twin filaments have been reeled and associated together. Raw silk is so absorbent of moisture, that it may be increased ten per cent, in weight by this means. This property has led to falsifications; which are detected by enclosing weighed portions of the suspecte 5 in fhro.fT wVM .r"«!" ^^^ ^^"'^- ^' ^' ^'^ ""''^^ ^^th hooks or eyelets at their ends, Ih^r^^h.fiV^ ? filaments run apart, and are kept from ravelling, c, c, the point! where he filaments cross and rub each other, on purpose to clean their surfaces, rf, is LTTiMTV^K*!! T" 5 P'" P°^"^' ^"^ ^^^^ the traverse molion alternately lo right and left, whereby the thread is spread evenly over the surface of the reel e. /,/, are the pulleys, which by means of cords transmit the rotatory movement of the cylinder rf. to the reel e. g, is a friction lever or tumbler, for lightening or slackening the endlesi SILK MANUFACTURE. 603 cord, in the act of starting or stopping the winding operation. Every apartment of a large filature contains usually a series of such reels as the above, all driven by one prime mover ; each of which, however, may by means of the tumbling lever be stopped at 1241 pleasure. The reeler is careful lo remove any slight adhesions, by the application of a brush in the progress of her work. The expense of reeling the excellent Cevennes silk is only 3 francs and 50 centimes per Alais pound ; from 4 to 5 cocoons going lo one thread. That pound is 92 hun- dredths of our avoirdupois pound. In Italy, the cost of reeling silk is much higher, being 7 Italian livres per pound, when 3 to 4 cocoons go to the formation of one thread ; and 6 livres when there are from 4 to 5 cocoons. The first of these raw silk& will have a tiire of 20 lo 24 deniers ; the last, of 24 lo 28. If 5 lo 6 cocoons go to one thread, the litre will be from 26 to 32 deniers, according to the quality of the co- coons. The Italian livre is worth 7|(i. English. The woman employed at the kettle receives one livre and five sous per day ; and the girl who turns the reel, gets thirteen sous a day ; both receiving board and lodging in addition. In June, July, and August, they work 16 hours a day, and then they wind a rubo or ten pounds weight of cocoons, which yield from l-5th to l-6th of silk, when the quality is good. The whole expenses amount to from 6 lo 7 livres upon every ten pounds of cocoons : which is about 2*. 8d per English pound of raw silk. The raw silk, as imported into this country in hanks from the filatures, requires lo be regularly wound upon bobbins, doubled, twisted, and reeled in our silk-mills. These pro- cesses are called throwing silk, and their proprietors are called silk ^Arotf^/ers ; terms pro- bably derived from the appearance of swinging or tossing which the silk threads exhibit during their rapid movements among the machinery of the mills. A representation of a French mill for throwing silk, is given in the Dictionnairt Technologique, under the article Moulinage de Soie. But it is a most awkward, operose, and defective piece of machinery, quite unworthy of being presented to my readers. It was in Manchester that throwing-mills received the grand improvement upon the ancient Italian plan, which had been originally introduced into this country by Sir Thomas Lombe, and erected at Derby. That improvement is chiefly due lo the eminent factory engineers, Messrs. Fairbairn and Lillie, who transferred to silk the elegant mechanism of the throstle, so well known in the cotton trade. Still, throughout the silk districts of France, the throwing mills are generally small, not many of them turning off more than 1000 pounds of organzine per annum, and not involving 5000/. of capital. The average price of throwing organzine in that country, where the throwster is not answerable for lass, is 7 francs ; of throwing trame, from 4 fr. lo 5 fr. (per kilogramme 7) Where the throwsfer is accountable for loss, the price is from 10 fr. to 11 fr. for organzine, and from 6 to 7 for trame. In Italy, throwing adds 3«. 9d. to the price of raw silk, upon an average. I should imagine, from the perfection and speed of the silk-throwing machinery in this eountry, as about to be described, that the cost of converting a pound of raw silk either into organzine or trame must be considerably under any of the above sums. SILK-THROWING MILL. The first process to which the silk is subjected, is winding the skeins, as imported, off npon bobbins. The mechanism which effects this winding off and on, is technicallf called the engine, or swift. The bobbins to which the silk is transferred^ are woodei %M 604 SILK MANUFACTURE. !i « cylinders, of such thickness as may not injure the silk by sudden flexure, and which may also receive a great length of thread without having their diameter materiallv increased, or their surface velocity changed. Fig. 1243, is an end view of the silk throwing machine, or engine, m which the two large hexagonal reels, called swifts, are 1243 Si"nfra?raulctd'' T^^ them, to which the bobbins and impelling «e frequently changed. The motion is communicated ,„ th^.'end onhrengTne sWn Si.' ..„^''* ^^" '''■''' '*' '^'X'™ •>«■•« '" "OSS section, is sometime^ of ereat Ien».), .^ tending 20 feet or more, according to the size of the apartment Uwn This ih." i'.?^; etym«,c^c''a',Ta'su\Y;Ts''j;ra JJirj^.'^ 7.%' trf^irreSnY.''! "■"' gular sowness, yet they do their work mnk quicker han ,„y of 'he "m anoa^J^t and ,n th,s respect may deserve their name. At every ei.hth or Li.h w?f.^. • '^ projecting horizontal piece l,, which carries at its end Sl,er"horizo„ tal bar? tiZ'kt iS«s™f''th: t'::^ " "" ""•""■ ™^ -""''='■' "■' sIender'ree;s°'or rwU^^ti^^ Z 1244 thestrucfireof the swifts will be fully understood. From the wo«itn shaft 6 ^j:^rt a ^l/f ^aJ' L« :'^:-:t^ Ira^e^i^ SILK MANUFACTURE. 605 ■re set between each pair of spokes, to stay them, and to keep the cord tight, e is one of the two horizonul shafts, placed upon each side of the engine, to which are afiixed a number of light iron pulleys g, g (shown on a double scale in^ig. 1245. (These serve, by friction, to drive the bobbins which rest upon their peripheries. To the Uble A,^g.l24.S,are screwed the light cast-iron slot-bearings i, i, wherein the horizontal spindles or skewers rest, upon which the bobbins revolve. The spindles (sec Fj^g. 1249.) carry upon one end a little wooden pulley A, whereby they press and revolve upon the larger driving pulleys g, of the shaft e. These pulleys are called $tars by our workmen. The other ends of the spindles, or skewers, are cut into screws, for attaching the swivel nuts i (Jig, 1249.) by which the bobbins k, k, are made fast to their respective spindles. . f..^ f.j^-^ I G * Besides the slots, above de- ^ //>.-^ H ™.,^r> scribed, in which the spin- dles rest when their friction pulleys A, are in contact with the moving stars g, there is another set of slots in the bearings, into which the ends of the spindles may be occasionally laid, so as to be above the line of coll- ect of the rubbing periphery of the star g, in case the thread of any bobbin breaks. When- ever the girl has mended the thread, she replaces the bobbin-spindle in its deeper slot-bear- ings, thereby bringing 1249 1246 its pulley once more into contact with the star, and causing it to revolre. 6 is a long ruler or bar of wood, which is supported upon every eighth or twelfth leg b, B. (The figure being, for convenience of the page, contracted in length, shows it at every sixth leg.) To the edge of that bar the smooth l^ass rods Jt, are made fast, over which the threads glide from the swifts, in M. I W ■ ii a i r ■ i 1 !ii ; «06 SILK MANUFACTURE, 1247 their way to the bobbins, h is the guide bar, which has a slow traverse or seesaw rot tion, sliding m slots at the top of the legs b, where they support the bars g. Upon th« guide bar h, the guide pieces /, I, are made fast. These consist of two narrow, thin, up. right plates of iron, placed endwise together, their contiguous edges being smooth, piral- leJ, and capable of approximation to any degree by a screw, so as to increase or diminish at pleasure the ordinary width of the vertical slit that separates them. Through this slii the silk thread must pass, and, if rough or knotty, will be either cleaned or broken ; in tne latter case, it is neatly mended by the attendant girl. The niotions of the various parts of the engine are given as follows. Upon the end of the machme, represented in fig. 1243 there are attached to the shafts e (fig 1244) the bevel wheels 1 and 2, which are set in motion by the bevel wheels 3 and 4, rJsnectivelv These latter wheels are fixed upon the shaft m,fig. 1243. m is moved by the main steam shaft which runs parallel to it, and at the same height, through the length of the enein* apartment, so as to drive the whole ran^e of the machines. 5 is a loose wheel or pulley upon the shaft rn, working in gear with a wheel upon the steam shaft, and which mav ^L?^""u .^^^^^*^^''^''^'*'^^"'°""^ ^^^ ^^"'^ lever or gearing rod o (/ig«. 1 243 and u- u u " ^^ ^""^"^ *^ ^** ^^ ^^^ ** ^^°''^- ^ »s * SP">^ w^eel upon the shaft n>, by Which the stud wheel 7 is driven, in order to give the traverse motion to the guide bar ?<;.o -l^^^^ *^ represented, with its appendages, in double size, ^g*. 1247 and 1J48 with Its boss upon a stud p, secured to the bracket q. In an eccentric hole 1248 t ^ .n -J ^oA^^ of the same boss, another stud r, revolvcs. Upon which the little wheeU, is fixed. This wheel *, is in gear with a pinion cut upon the end of the fixed stud p ; and upon it is screwed the little crank t, whose collar is connected by two rods u (figs. 1243 and 1244), to a cross-piece v v/hich unites the two arms w, that are fixed upon the guide bar h, on both sides of the machine. By the revolution of wheel 7, the wheel s will cause the pinion of the fixed stud p to turn - ^ , , , round. If that wheel bear to the pinion the proportion of 4 to 1, then the wheel s will make, at each revolution of the wheel 7 one fourth of a revolution ; whereby the crank t will also rotate through one fourth of a turn so as to be brought nearer to the centre of the stud, and to draw the guide bar so much Jess to one side of its mean position. At the next revolution of wheel 7, the crank / will move through another quadrant, and come still nearer to the central position, drawing the guide bars still less aside, and therefore causing the bobbins to wind on more thread in their middle than towards their ends. The contrary eifect would ensue were the guide bars moved by a single or simple crank. After four revolutions of the wheel 7 the crank t will stand once more as shown in^g. 1248 having moved the bar h through the whole extent of its traverse. The bobbins, when filled, have the appearance renre sented in^g. 1250 ; the thread having been laid on them all the time in diagonal lines so as never to coincide with each other. " ' Doubling is the next operation of the silk throwster. In this process, the threads ol two or three of the bobbins, filled as above, are wound together in contact upon a single bobbin An ingenious device is here employed to stop the winding-on the moment that one of these parallel threads happens to break. Instead of the swifts or reels, a creel is here mounted for receiving the bobbins from the former machine, two or three beinff placed in one line over each other, according as the threads are to be doubled or trebled iv.u lu^J?"?^^"'^ *^ '" ""*"y respects like the engim, it has some additional parts! whereby the bobbins are set at rest, as above mentioned, when one of the doubling threadt gels broken. =• "'tcauB -Ftg.l251is an end View from which it will be perceived that the machine is, like the preceding, a double one, with two working sides. ' ^ig.l252is a front view of a considerable portion of the machine, i'ngff bobbin^°^^ part of a cross section, to explain minutely the m^e of winding upon • Fig. 1254is the plan of the parts shown in^g. 1253 ; these two figures being drawn to double the scale ofylg*. 125 land 1252. ««" w A, A, figs. 1251 ^1262, are the end frames, connected at their tops by a wooden stretcher or bar^eam, «, which extends through the whole length of the machine ; this bar is shown also in/g«. 1253 and 12o4. B B, are the creels upon each side of the machine, or bobbin bearers, resting upon wooden beams or boards, made fast to the arms or brackets c, about the middle of th« frames a. D, D, are two horizontal iron shafts, which pervade the whole machine, and carry a •enes of light moveable pulleys, called stars, c, c, (figs 1 253,1 254.)which serve to drive tht t>n.K MANUFACTUllE. 607 bobbins e, e, whose fixed pulleys rest upon their peripheries, and are therefore tomed wnply by friction. These bobbins are screwed by swivel nuts «, c, upon spindles, as m the silk engine. Be. sides the small friction pulley or boss, d, seen best in fig. 1254, by which they rest upon the star pulleys c, c, a little ratchet wheel /, is attached to the other end of each bobbin. This is also shown by itself at/, in ^g. 1255. The spindles with their bobbins revolve in two slot-bearings F, F, fig. 1254, screwed to the bar-beam a, which is supported by two or three interme- diate upright frames, such as a'. The slot bearings f, have also a second slot, in which the spindle with the bobbin is laid at rest, out of contact of the star wheel, while its broken thread is being mended, g is the g-uide bar (to which the cleaner slit pieces g, g, are attached), for H 1252 i ^=q^^^^jg^ frT~r^ ^p=!^ *^m '^1 n II II II i( II II N ^™™ ^^^*^^^ making the thread trayerse to the right and the left, for its proper distribution over the surface of the bobbin. The guide bar of the doubling machine is moved with a slower traverse than m the engine ; otherwise, in consequence of the difl^erent obliquities of the paths, the single threads would be readily broken, h, h, is a pair of smooth rods of iron or brass, placed parallel to each of the two sides of the machine, and made fast to the standards H, h, which are screwed to brackets projecting from the frames a, a'. Over these rods the silk threads glide, in their passage to the guide wires g, g, and the bobbins e, e. I, I, is the lever board upon each side of the machine, upon which the slight brass beanngs or fulcrums t, t, one for each bobbin in the creel, are made fast. This board bears the balance-lever k I, with the falters n, n, n, which act as dexterous fingers, and Btop the bobbin from wmdmg-on the instant a thread may chance to break. The levers ft, /, swing upon a fine wire axis, which passes through their props t, t, their arms being shaped rectangularly, as shown at fc, fc',yig. 1254. The arm /, being heavier than the arm fc, naturally rests upon the ridge bar w?, of the lever board r. «, «, «, are three wii es, resting at one of their ends upon the axis of the fulcrum t, i, and having each of their other hooked ends suspended by one of the silk threads, as it passes over the front steel rod h. and undei III! \ S 608 SILK MANUFACTURE. iriti.^ ^ ^^'^K'^''*^,'*^''**^^**"^^'!'*r« ^""'^^ truly in their up-and-down motioni with the thread, by a cleaner-plate o, having a vertical slit in its middle. Hence, when- ever any thread happens to break, in its way to a winding-on bobbin k the wfre n^ 1258 ^ I which hung by its eyelet end to that thread, as it passed through between the steel rods in the line of A, A', falls upon the lighter arm of the balance lever fc, /, weighs down that arm fc, consequently jerks up the arm /, which pitches its tip or end into one of the three notches of the ratchet or catch wheel / (Jigs. 1254 & 1255), fixed to the end of the bobbin. Thus its motion is instantane- ously arrested, till the girl has had leisure to mend the thread, when she again hangs up the faller wire n, and restores the tJnn TP ^o««^k-i I. . 1 . leverfe,/, to its horizontal posi- t on. If; meanwhile, she took occasion to remove the winding bobbin out of the sunk slot-bearing, where pulley d touches the star wheel ., into the right-hand upper slot of repose, she must now shift it into its slot of rotation. ^^ The motions are given to the doubling machine in a very simple way. Upon the end of the framing, represented in^g 1251, the shafts d, d, bear two spur wheels 1 and 2, which work into each other. To the wheel 1, is attached the bevel wheel 3, driven by another bevel wheel 4 (Jig. 1252), fixed to a shaft that extends the whole length of the apartment, and serves, therefore, to drive a whole range of ma- chines. The wheel 4 may be put in gear with the shaft, by a clutch and g'ear- handle, as in the silk engine, and thereby it drives two shafts, by the one transmitting Its movement to the other. js effected as follows = -iT^n one of ,he shafts .^'.L'r^l^TbTrwhed 5 'dtl„1",h°^ S^-Jlr >. ' "IT ""f- '"? °^ 'he upright shaft p (fig. 1252, to the ri-hrof the .Jailer which is fixed to the e'„d of ':h:^fve'^';';Ue\ Ki^ f t^TT^r'^Ihe' rrb^^s^e^-^rehioirtre^.V/zr t7^f:ttr"^ji whTi?tCrsr;rt tJ:^!^^ i^ ^rhKnt"; .^e^:fdi^:/thfp^«^sP^^ The motion is given to this shaft in the following w«v TTr,«« ♦!,« u • . • AaO J, there is a bevel wheel g (fig,. 1252 and 125^ "v\ie?'dVi,eYKe ^LlToT^l the shaft a:; on whose upper end, the worm v work-in ih» «ill i 11 ^ r ^/."P?" JJi: r=eS'tt'-irclli:dTe'''^pi„t'f ^r^ i^X"-"'' '^r - '5'" twisted in one direction, next doubled and tl^ln%w!*P^ t »^^^ -^ u^"^ singles are first an exceedingly wiry, compact thread, Co^^^^^^^^ theopposite direction, either the singles or the doubled silk whilTbei?^ unwoS ?ror*nnJ . VC!l'"""''"i wound upon another set, is subjected to a reef, W ^LI^" '^^°™ °"^ ^^f °^ bobbms, and the thread is conducted ^s usuathrouSi -aides ^^^^^ S?**"*''"n ' *" "^^['^ ^^'^^^^^ by a proper mechanism. ^ " ^''' *"^ "''^^^ diagonally upon the bobbins J't^. 1256 exhibits an end view of the soinninw t«:n . :« ^u-^x, r i • ». .re shown ; two tiers upon each side, one Xv^e Vler*"^ w\JZin7 mlSf Lav" SILK MANUFAGTC/RE. 609 1266 Ihicc working tiers upon each side; but as the highest tier must be reached by a laddex or platform, this construction is considered by many to be injudicious. J^iff. 1267, ia a front view, where, as in the former figure, the two working lines are shown. Ficf. 1258, is a cross section of a part of the machine, to illustrate the cod- struction and play of the working parts ; ^gs. 1264, 1265, are other views of J^. 1258. Fir/. 1259, shows a single part of the machine, by which the bobbins are made to revolve. Figs. 1260, and 1261, sliow a dif- ferent mode of giving the traverse to the guide bars, than that represented in Jig. 1268. Figs, 1262, and 1263, show the shape of the full bobbins, produce! by the action of these two different traverse motions. The upper part of the machine oeing exactly the same as the under part, it will be sufficient to explain the construction anii operation of one of them. A, A, are the end upright frames or standards, between which are two or three intermediate standards, accord- ing to the length of the machine. They are all connected at their sides by beams b and c, which extend the whole length of the machines, d. d, made fast to the beams b, and their These two bars together are «re the spindles, whose top bearings o, a, are bottoms turn in hard brass steps, fixed to the bar c. ^ 1257 Wi 610 SILK MANUFACTURE. 4. called, by the workmen, the spindle box. The standards A, a, are bound with cwbb Wun Mm. Urn SILK MANUFACIURE. 611 Vj N. the' Unll'of^E r Y/?256 1 W ^f J 'Z'^ ^V r'"^ x^^^'" '^' ^«"^«»t*l ^in cylinder in the J nes ol e, e, Jig. 1256 lying m the middle line between the two oarallel rows of spindles D, D F, F, are the bobbins containing the untwisted doXd sS wh'ch a^ simply pressed down upon the taper end of the spindles, d, d, are Uuie fl^ers,^ forked wings of wire, attached to washers of wood, which revolve W upon the^ops of the said bobbins f, and round the spindles. One of the wings is somethn^ S upwards to serve as a guide to the silk, as shown by dotted lines in fig. U 58 TiZTe pieces of wood pressed upon the tops of the spindles, to prevent the flfers froin ttartLg off by the centrifugal force, g, are horizontal shafts bearing a number of Tittle sou? ?^ff I' ¥' !!' ""'1 slot-bearings, similar to those of the doubling-mSne wh ch S^e fixed to the end and middle frames. In these slots, the li^ht square casi-iron shafts ^J spindles g,/.g. 1257 are laid, on whose end the spur wheel h is Sst ; and when the shaft ^ lies in he front slot of its bearing, it is in gear with the wheel /, upon the snaft g bu^ when It IS laid m he back slot, it is out of ^ear. and at rest. See f, f, fiTlo^l ' Upon these Jittle cast-iron shafts or spindles g.fig. 1259. the bobbins or blocks i, are thrust, for receiving, by winding-on, the twisted or spun silk. These blocks are made of a large diameter, in order that the silk fibres may not be too much bent ; and they are but slightly fillevL at each successive charge, lest, by increasing their diameter too much, they should produce too rapid an increase in the rate of winding, with propor- tional diminution in the twist, and risk of stxetch- mg or tearing the silk. They are therefore the more frequently changed, k, k, are the guide bars, with the guides i, t, through which the silk passes, being drawn by the revolving bobbins i, and delivered or laid on by the fliers d, d, from the rotatory twisting bobbins f. The operation of the ma- chine IS therefore simple, and the motions are given to the parts in a manner equally so. Upon the shaft of the tin cylinder or drum, exterior to the frame, the usual fast and loose pulleys, or riggers, l, l', are mounted, for driving the whole machine. These riggers are often called steam-pulleys by the workmen, from their being connected by bands w;ith the steam-driven shaft of the factory. In order to allow the riggers upon the shafts of the upper and the under drums to be driven from the same pulley upon the main shaft, the axis of the under drum is prolonged at r, L', and supported at its end, directly from the floor, by an upright bearing. Upon the shafts of the tin cylinders there is also a fly-wheel m, to equalize ihe motion. Upon the other ends of these shafts, namely, at the end of the spinning- mill, represented in ;?g. 1256, the pinions 1 are fixed, which drive the wheels 3, by means of the intermediate or carrier wheel 2; called also the p ate wheel, from its being hollowed somewhat like a trencher. 1, is called the change-pinion, be- cause It IS changed for another, of a different size Uieveloc-tvnf wV,«-ro A o ' . i. *"^ ^^fferent number of teeth, when a change in be alSt 1 thf th ^"9 • '' ^"^ ^ r^'^'' ^"^ ""^^ * ^'^^'' «^ ^"^^"er pinion to DC applied at 1, the wheel 2 is mounted upon a stud fe, which is moveable in n «lnt /.nrT t^^ZT 'l" "^'^ ef.'he.^hed 3. Tu! sM is a brin^hfrom ThJ cr^'bar t n'e smaller he change-pnuon is, the nearer will the stud k approach to the vertical Ine iZH^ T. T'"' "^ I^^V ""u" ^ \ """ '"« "">« slowly will the pUte wherf 2l^ driven. To the spur wheel 3, a bevel wheel 4, is fixed, with which the other also revolves loose upon the stud. The bevel wheel 5 upon the shaft ;,is driven by the wS whee 4; and .t communicates motion, by the bevel wheels 6 and 7, to each of the Wi- .ontal shafts g c extending alon? the upper and under tiers of the machine. A, .he o ,tw ,r ^ °'^ • " '°? T l^-^^- '-^^-'''^ '"» ''''«'« 6 «»d 7 are omitted, on purpos^ itrs'of%'e™b;;£:.' '" ^""^ "• "^ "^ "^ ^'"'-'-""'^ «" ««^'"s '^« ^^•^ If it be desired to communicate twist in the opposite direction to that which would be given by the actual arrangement of the wheels, it is necessary merely to transpose the carrier wheel 2, from its i)resent position on the right hand of pinion 1, to the left o'f it, and to drive the tin cyliuder by a crossed or close strap, instead of a straight or open one. The traverse motion of the guide is given here in a similar way to that of the engine, (fig' 1243.) Near one of the middle or cross-frames of the machine (see fig. 1258) the wheel /, in gear with a spur wheel /i, upon one of the block-shafts, drives also a spur wheel m, that revolves upon a stud, to which wheel is fixed a bevel wheel n, in gear with the bevel wheel o. To wheel o, the same mechanism is attached as was described under/g«. 1247 and 1248, and which is here marked with the same letters. To the crank-knob r,j^^. 1269,a rod ar, is attached, which moves or traverses the guide bar belonging to that part of the machine ; to each ma- chine one such apparatus is fitted. In ^g«. 1260 and 1261 another mode of traversing the guide bar is shown, which is generally used for the coarser qualities of silk. Near to one of the middle frames, one of the wheels fy in gear with the spur wheel m, and the bevel wheel «, both revolving on one stud, gives motion also to the wheel 0, fixed upon a shaft -, a', at whose other end the elliptical wheel 6' is fixed, which drives a second elliptical wheel c', in such a way that the larger diameter of the one plays in gear with the smaller diameter of the other ; the teeth being so cut as to take into each other in all positions. The crank-piece d' is screwed 1262 1263 upon the face of the wheel c', at such a distance from its centre as may be necessary to give the desired length of traverse motion to the guide bar for laying the silk spirallv upon the blocks. The purpose of the elliptical wheel is to mod'ii'y the simple crank motion, which would wind on more silk at the ends of the bob- bins than in their middle, and to effect an equality of winding- on over the whole surface of the blocks. In ^g-.1261 the elliptical wheels are shown in front, to illustrate their mode of operating upon each other. Fig. 1262 is a block filled by the motion of the eccentric, fig. 1258; and fig, 1263 is a block filled by the ellip- tical mechanism. As the length of the motions of the bar in the latter construction re- mains the same during the whole operation, the silk, as it is wound on the blocks, will slide over the edges, and thereby produce the flat ends of the barrel in fig. 1263. The conical ends of the block (fig. 1262) are produced by the con- tinually shortened motions of the guide bar, as the stud ap- proaches, in its sun-and-planet rotation, nearer to the genera] centre. i''tg».l 264,1 265 are two different views of the differential me- chanism described under yig. 1258, The bent wire x, ^g. 1258, is called the guider iron. It is attached at one end to the pivot of the sun-and-planet wheel- 7 work /, 4, 0, and tt 1264 K i 1265 cm H umik ^ W '6 the other to the guide bar /, /, fig. 1257, The silk threads pass through the guides, as already explained. By the motion communicated to the guide bar (gvtder), the diamond pattern is produced, as shown in^g. 1262. — ":-i" I—" fi ■■ TCi "=' ■ - - ;-t~^" T "^ i I -A I w mi 612 SILK MANUFACTURE. THE SILK AUTOMATIC BE£L. In this machine, the silk is unwound from the blocks of the throwing-mill, and formed into hanks for the market. The blocks being of a large size, would be productive of much friction, if made to revolve upon skewers thrust through them, and would cause frequent breakage of the silk. They are, therefore, set with their axes upright upon a board, and the silk is drawn from their surface, just as the weft is from a cop in the shuttle. On this account the previous winding-on must be executed in n very regular manner; and preferably as represented in fig. 1'1&2, fig.l266isafront viewof the reel; little more than one half of it being shown. Fig. 1267 is an end view. Here the steam pulleys are omitted, for fear of obstructing th« D 1266 view of the more essential parts, a, a, are the two end framings, connected by mahogany stretchers, which form the table b, for receiving the bobbins c, c, which are sometimes "weighted at top with a lump of lead, to prevent their tumbling, d is the reel, consisting of four long laths of wood, which are fixed upon iron frames, attached to an octagonal wooden shaft. The arm which sustains one of these laths is capable of being bent in- wards, by loosening a tightening hook, so as to permit the hanks, when finished, to be taken oflT, as in every common reel. The machine consists of two equal parts, coupled together at a, to facilitate the removal of the silk from either half of the reel ; the attendant first lifting the one part, and then the other, b is the guide bar, which by a traverse motion causes the silk to be wound on in a cross direction. 6 and c are the wire guides, and d are little levers lying upon the cloth covered guide bar e. TTie silk, in its way from the block to the reel, passes under these levers, by which it is cleaned from loose fibres. ^^ ^ On the other end of the shaft of the reel, the spur wheel 1 is fixed, which derives mo tion from wheel 2, attached to the shaft of the steam-pulley f. Upon the same shaft there is a bevel wheel 3, which impels the wheel 4 upon the shaft «; to whose end a plate 18 attached, to which the crank /is screwed, in such a way as to give the proper length of traverse motion to the guide bar e, connected to that crank or eccentric stud by the jomted rod g. Upon the^shaft of the steam-pulleys f, there is a worm or endless I^a"^' IV %^..?^-C'H'^^^l''^^'^^ ^°'^^ ^" » ^^*^el 5> attached to the short upright shaft /t (fig. 1266). At the end of A, there is another worm, which works in a wheel 6 • at whose circumterence there is a stud i, which strikes once at every revolution a^'ainst an arm attached to a bell, seen to the left of g ; thus announcing to the reel tente'r that a measured length of silk has been wound upon her reel, e is a rod or handle, by which the fork /, with the strap, may be moved upon the fast or loose pulley, so as to set on or arrest the motion at pleasure. Throwsters submit their silk to scouring and steaming processes. They soak the SILK. 613 hankS; as imported, in lukewarm soap-water in a tub ; but the bobbins of the twisted single silk from the spinning mill are enclosed within a w^ooden chest, and exposed to the opening action of steam for about ten minutes. They are then immersed in a cistern of warm water, from which they are transferred to the doubling frame. The wages of the workpeople in the silk-throw- ing mills of Italy are about one half of their wages in Manchester; but this difference is much more than counterbalanced by the protecting duty of 2s, lOd. a pound upon thrown silk, and the superior machinery of our mills. In 1832, there was a power equal to 342 horses engaged in the silk-* throwing mills of Manchester, and of about 100 ia the mills of Derby. The power employed in the other silk mills of England and Scotland has not been recorded. r ^ ; • i : , There is a peculiar kind of silk called marabouty containing generally three threads, made from the white Novi raw silk. From its whiteness, it takes the most lively and delicate colors without thc' discharge of its gum. After being made into tram by the single twist upon the spinning mill, it is reeled into hanks, and sent to the dyer without fur- ther preparation. After being dyed, the throwster re- winds and re-twists it ui>on the spinning mill, in order to give it the whipcord hardness which consti- tutes the peculiar feature of marabout. The cost of the raw Novi silk is I9s. 6d. a pound; of throw- , „ _.>^.\ ^'^o ^^ ^^^^ tram, 2s. 6d. ; of dyeing, 2*. •, jf re-wind- ■H i i' '^ m m ing and re-twisting, after it has been dyed, about 5«.; of waste, 2a., or 10 per cent. : the total of which sum is 31 a. ; being the price of one pound of marabout in 1832. SILK. Several pieces of silk were put into my hands, for analysis, on the I8th of February, after I had, on tht preceding 12th of the month, visited the St. Katharine's Dock warehouses, in New street, Bishopsgate street, for the purpose of inspecting a ' large package of the Corahs, per Colonist. I was convinced, by this inspection, that,' notwithstanding the apparent pains bestowed upon the tin plate and teakwood packing- cases, certain fissures existed in them, through which the atmospheric air had found access, and had caused iron-mould spots upon the gunny wrapper, from the rusting or ' oxidizement of the tinned iron. I commenced my course of analysis upon some of the pieces which were most damaged, as I thought they were most likely to lead me to an exact appreciation of the cause of the mischief; and I pursued the following general train of research : — 1. The piece of silk, measuring from 6 to 7 yards, was freely exposed to the air, then weighed, afterward dried near a fire, and weighed again, in order to determine its hygrometric property, or its quality of becoming damp by absorbing atmospheric vapor. Many of the pieces absorbed, in this way, from one tenth to one eighth of their whole weight; that is, from 1 oz to 1| oz. upon 13 oz. This fact is very instructive, anU shows that the goods had been dressed in the loom, or imbued subsequently, with some very deliquescent pasty matter. 2. I next subjected the piece to the action of distilled water, at a boiling tempera- ture, till the whole glutinous matter was extracted ; five pints of water were employed for this purpose, the fifth being used in rinsing out the residuum. The liquid wrung out from the silk was evaporated first over the fire, but toward the end over a steam bath, till it became a dry extract; which in the damaged pieces was black, like extract" of liquorice, but in the sound pieces was brown. In all cases the extract so obtained absorbed moisture with great avidity. The extract was weighed in its driest slate, and the weight noted, which showed the addition made, by the dressing to the weight of the silk. The piece of silk was occasionally weighed in its cleansed state, when dry, as a check upon the preceding experiment. 3. The dry extract was now subjected to a regular chemical analysis, which was mollified according to circumsUnces, as follows : 100 parts of it were carefully igni/ ted in a platinum capsule ; during which a considerable flame and fetid smoke were disengaged. The ashes or incombustible residuum were examined by the action of dis- tilled water, filtration, as also by that of acids, and other chemical tests, whereby thc constituents of these ashes were ascertained. In the course of the incineration or cal- cination of the extract from the several samples, I never observed any sparkling or scintillation ; whence I inferred that no nitre ha4 been used in the dressing of the goods, as some persons suggested. 614 SILK. Wing minute course of researches, in order to discover whether the urine of man had of"the"rd'«tlct In alcoholTo^ '''''' f ^'^ ^"^^ T^' ' ^^'^ ^^^ aTrtlTortioa ot the said extract m alcohol, 60 per cent, over proof, which is incapable of dissolvine the nee water or other starchy matter, which might be properly appM ?o the sHk ?f the loom. The alcohol, however, especially when aided by a moderate hear^^^^^^ of tZnTrin: "ThrrlolTf "^ ^r^' "'^^\^^ ^^' characteristic constituti^ 01 numan urine. The alcohol took a yellow tint, and being, after subsidpnop nf thp lt^Z^\fA"%'i '^'" f ^"^^ ^ ^^^^^ '^^«^' and 'exposed to^hTgentle hea^of a w^^^ nn» ^^^^ Vk '^'"^^ ''■^' ^i^*' '^*° ^^« receiver, and left a residuum in the retort which hpft n?99noV'''P^'''' ''^^'^^'. ^^'' ^"^«^^^^^ ^^« ««lid when cold, Wt mehed at a heat of 220^ F.; and at a heat of about 245^ it decomposed with the producUon of wa Tir.L'^^^'^^V^ ammonia-the well-known products of urea at S^fmpei^^ture' lan.fp,^ w^K''^*°^^"^^7^' ^"^ ^^'^^^"^ ^« the smell, and was made^S ariy manifest by its browning yellow turmeric paper, exposed in a moist state to the fump/ ^ffectTd^TttusTbt '•' T' V^^'^.?^^^ ^'^' ^^ -^-h th^ decomVoshion'wL uta^'; ettected. I thus obtained perfect evidence that urine had been employed in India in KnwiT '^' P^'" "" '^ ^i^'^ ^ ^^^^t °^«^y «^ th« pieces had beenX sed it S known to every experienced chemist, that one of the most fermentative or pitrefai TtllhT^'^''^^' ''^''^ "^^ ^' °^^^^' ^^«^t« fr«°» the mixture of humL urfne w^^^ starchy or gummy matter, such as rice water ; a substance which, by the test of iodine ne'^n^cSn^^retusr^^^^^'' " ' ^'^"^' ^° ^^^ ^^"^^^^ present?l\^^rvtt ' 5. On incinerating the extract of the Corahs, I obtained, in the residuum » nnt«Kio Z^Vj.f ''T "'^"'^ S7^^^'' ^y ^h*' ^^«t of chloride of plaCm,prov^^^^^^ potS But, as the extract itself was neutral to the tests of litmus and turmeric naneri™ D?Z?pTh?tw' ^'^^??"' '5*^ ^^^ ^^tract contained some vegetaT acTprobnZ produced by the fermentation of the weaver's dressing, in the hot climate of HiEan Lnl i?t'v ^^^' examined the nature of this acid, by distilling a portbn of the extraci along witv some very dilute sulphuric acid, and obtained in the receiver a notablp quantity of the volatilized acid condensed. This acid might be the acelic Cvinelarl the result of fermentation, or it might be the formic orTcId of ants the result of ThP ;fi;n?pf '"\P^"::L' ^^'^ ^P.^^ ^^^^^^y ^^"er. to decide this pLt^lUturated the saM m, " ?/''.^'''^r "^^g'^^^}^' a°d obtained on evaporaUon the characteri tic gum^^^ mass of acetate of magnesia, soluble in alcohol, but none of the cnstals of forn^X of froT thP Nn°'"^"^\' '^ *l'"^'- ^'""^ the quantity of alkali (p^tSa whkh"^^^ from the incineration of the extract of one piece of the damaged silk and whioh ZZffZ '^- r'^'V ^""^^ ^ ^"^ ^^•^^^"^^'l that wood astThad be^n addl^ n India, to the mix ure of sour rice water and urine, which would therefore constitute a compound remarkably hygrometric, and well qualified to keep the wa% of the web t"kintTpon^t Thi'tTr^^^ ^'^ '^^^ ^^«* the Tantyo? weaver™ m«fr!? r P \ ., *^^tate of potassa, present in the said Corahs, is one of thP most deliquescent salts known to the chemist : and, when mixed with femented urine ^JZ^T"^ ^'^'''' hygrometric dressing-one, likewise, which wUl readUy generate 6. That the dressing applied to the webs is not simolv a dPP«nt.«« «r • v very manifest, by comparing the incinerated res dCrnVrice w'^^^^^ siduum of the extract of the said Corahs. I find that 100 CTainTnf tl *?"?^^^ted re- a platinum capsule, leave only about one fifth of a Jain ?r ifn ^on ^f • "'"T^'^i" matter, which is chiefly silicious sand; whereas when 100^ Jn. r «^^^<^«°^bustible of several of these Corihs were similariy incSerthey feft nlT^r ""''"'* busUb e matter. This consisted chiefly of alumina or S of clavUIh^i-' ""^ '"'^°'' and a litUe common or culinary salt. (Has the cUbe^n added ^n,-^''^'''''- ^^^S?'** Chester, to give apparent substance to the thin siJk leb ?) ' ' " ^''''^ '^ ^*^- staXuringtp'eVoforf^u^^^^^^^^^^ f w^^uT^^^' 4i^ ^^^-^ - ^^-ost con- J^e of the sai'd go'ods had bee\' -rasionerby'Th^e'vU^^ ^ the dam, them in India; which, as I have said under thpJfl, ^'^essing which had been put into them to become more or lesr^ldeTed^n nrnnLr ?'!u^^^ ^^^^ ^^^ ^''^ ^""^ ^^"^ed packed at Calcutta, and to thraSal iH^^^ ^ "^'^ ^"^'-"^^ ^^°^P°^«« ^^^^ ring the voyage from Calcutta toLSon ^^'''' "^ atmospheric au: into the cases du. The following is the list of Corahs which I chemically examined :- SILK. 615 1 and 2, per Colonic, from Calcutta, 2 pieces, sound. — ^These two pieces had been dressed with a sweet viscid matter, like jaggery or goor (molassy sugar), mixed with the rice water. This extract contained no urine, but emitted a smell of caramel or burned sugar, when ignited. It amounted to 270 grains in the one, and 370 in the other. 3, ditto, 1 piece, mildewed, 1st degree. — ^This piece had been dressed like No. 5, and contained no trace of urine. It aflbrded 400 grains of a most deliquescent sweetish glutinous matter. 4, ditto, 1 piece, mildewed, 1st degree, as No. 3. 5, ditto, 1 piece, mildewed, 3d degree. — This piece contained no trace of urine, but it afforded 210 grains of a light brown extract, being rice water, mixed with something like jaggery. 6, ditto, 1 piece, 3d degree, mildewed. — This piece aflbrded evidence of urine in it, by test of carbonate of ammonia. The extract amounted to 320 grains. 8, ditto, 2 pieces, damaged in the 3d degree. — The total weight of one of these pie- ces, after exposure to air, was 4,610 grains, and it lost 440 grains by drjing. The total weight of the other was 4,950 grains, and it lost 320 grains by drying. The weight of extract was, in one piece, 210 grains ; and both pieces contained abundant traces of urine, as well as of potash. These constituents, along with the rice water, accounted sufliciently for the great damage of these two pieces by mildew. 10, ditto, 2 pieces, sound. — These contained no urea. Each afl"orded from 300 to 600 grains of a light brown vegetable extract. 12, ditto, 2 pieces. — The extract in the one amounted to 222 grains, and in the other to 330. Both contained urea, and had, therefore, been imbued with urine. 14, ditto, 2 pieces, mildewed, 3d degree. — There was no urea in the extracts from these two pieces ; but they aflforded, the one 300 grains of extract, and the other 750. But this extract was a saccharine molassy matter, impossible to dry over a steam heat. The same quantity as the last, if dried by stronger means, would have weighed proba- bly 600 grains. Its extraordinary deliquescence kept the pieces very moist, and there- by caused the mildewing of them. With the saccharine matter, four per cent, of culi- nary salt was mixed in one of these extracts. 16, ditto, 2 pieces, 3d degree of mildew. — ^The extract, about 200 grains, contained abun 'ant evidence of urea, and, consequently of urine. 18, ditto, 2 pieces, sound. — Both these contained some traces ot urea ; but the one yielded only 102 grains of extract, and the other 370 grains. They must have been well screened from the air to have resisted the action of the urine. 20, ditto, 2 pieces, damaged, 1st degree. — No urea. The extract of the one was 320 grains ; of the other piece 380 ; and it had a light brown color, being a sacchanne mucilage. 22, ditto, 2 pieces, 3d degree mildew. — 200 grains of extract in the one, and 210 io the other : they contained urea. 24, 2 pieces, 3d degree of mildew. — 310 grains of extract in the one, and 180 grains in the other. Both were impregnated with urea, and consequently with urine. Having in the preceding report demonstrated, by the clearest processes of chemical research, that the above mildewed Corahs had been damaged by the fermentative de- composition of the dressing paste with which they had been so abundantly impregnated, I would recommend tne importers of such goods to cause the whole of the dressing to be washeJ out of them, and the pieces to be thoroughly dried, before being packed up. I believe that clean silk may be kept and transported, even in the most humid atmo- sphere, without undergoing any change, if it be not imbued with fermentative paste. I examined eight other pieces of a different mark, imported by another mercantQe house,. per Colonist, and they afforded results similar to the above. The beautiful and artistic silk trophy, occupying the entrance to the "Western Nave of the Exhibition, did not fail to attract notice. This trophy consisted of an elegant arrangement of rich tissues, brocades, damasks, and other fumitm'e, silks, the whole of ■which had been manufactured by Messrs. Keith & Co., and was surmounted by a silken banner. A variety of rich and costly productions of the Spitalfields loom were exhibited in the Galleries. The colours and textures of these fabrics were of great brilliancy and finish. An in- teresting collection of specimens of the raw and manufactured material was also exhibited Specimens of silk-plush for various purposes and in imitation of furs were likewise found among these articles. The ribands of Coventry^ have acquired a universal reputation ; and this characteristic manufacture was well represented in the number and variety of the articles exhibited. The application of steam power as a substitute for hand-weaving in this manufacture is making rapid progress, and some of its results were apparent. At present the United Kingdom draws its supply of the raw material for manufac- ture principally from the East Indies; and France, Italy, Turkey, and China, also- 616 SILK. liii m ! this vase quantity of textill fibJTis the r^uU of rte J^Z'tA «"«°''>e.r<>d that aU guned of the importance of things seemingly in° igJUfirnt "^ ^*' "" '** "^^ ** Manchester exhibited Gros de Nanles a-ovince of Venice The Tyrol - The other provinces - to 250,000 cwt 200,000 28,000 12,000 Or, in round numbers, 500,000 cwt. ^""^^ ^^^'^^^ *'^*- The cocoons are prepared at the reeling establishment into raw sHkr FrnT« f>, i* of mquines, it wou d appear that Lombardy comprises sofioTp!^?; ^V\^ ""^^^ which employ 79 500 workneonlp wWlim^fVoi? '^°™P"^^^ ^'06') reehng establisliments, ments, whIchVre noi taSd'^L^Ws enumeratto"^"^^^^^ the smaller establish-' 8,612 000 Vienna lbs. ; and sinc^ 12 lirof c^t^^VieU iTh „f P'-'>^"«'»\'»n<'"nts to qmred for this aggregate of raw silk 3(X)4(K)cwrof S„„ meZ„7^ "j"" "" "" qnired ,n e^ess of the quantity produced, an excS of LarivSn^f^"^""'' '^' ^w';?rt'"=*'°" ni^ 6,410 Do. 2.650 Do. none. Raw Silk 48-2,643 Thrown Silk 66,560 The Imports warehoused in December were — China - - 1,877 bales Bengal - 1,262 bales Chinese Thrown 20 bales Italian Raw - 204 Brutia - 86 Persian - - 858 Italian Thrown 107 Greek - - 6 Canton - - 1414 Of tlie above, 237 bales China were at the port of Liverpool B! ■ I n ;'i!! 618 SILK. An Account of the Imports, Consumption, and Stock of Silb: in 1860 and 1851. Deieription. Imports 1850. Imports I85I. Kxtreme Prices during 1850. Extreme Prices during 1851. Consump- tion. 1850. CoDsiunp- tion. 1851. Stock aisc Dec. 1850. Stock 3Ut Dec. 1851. Prices 1st JiUI. 1851. 1 Prices 1st Jan. 1859. CHINA—* Ts^ttlee Tuyssam Coiitun Chin Chew Thrown BENGAL " BRHTIA PERSIAN GREEK SYRIAN riAUAN— Raw Thrown lbs. 1,325,082 611,836 llu,16ij ll.8;« 66.:84 1,510,350 443,410 210,435 21.15U 1,140 629,300 440,800 lbs. 1,219,488 621,810 361,119 32,088 56 000 1,233,810 186,600 226,950 13,200 10,850 562.310 363,080 «. d. t.d. 14 6®22 9 6 n 6 8 6 13 9 15 8 16 6 19 6 5 6 19 6 11 18 8 6 11 13 21 20 9 26 16 28 6 18 6 31 «. d. i.d. 14 6® 22 10 11 6 10 14 4 6 10 15 6 18 6 5 19 11 18 8 6 no 12 21 18 9 22 11 28 6 19 80 6 lbs. 1,453,500 423.198 311.2 21,248 21,198 1.393.050 394.040 253,650 23.100 1,140 699.480 542,o00 lbs. 1,238,994 691.182 282,401 40.606 61,160 1,25^,340 216,0 '0 289.500 13.650 10,850 631.130 41)6,580 lU. 681.156 301,134 19,9- .8 11,424 31.856 1,000.350 113.600 18.000 4,500 none 306. Sio 159,5(10 Ibi. 191,660 9;n,16;i 165,286 2.85A 26,096 981,ShO 94.300 15,450 4,1)50 none 232,000 U6,000 t. d. #. d, 18 6@22 19 116 10 18 6 56 80 18 18 6 5 6 19 13 10 90 106 14 21 00 000 19 28 6 19 6 30 6 *.d. I.d. 16 0@20 10 6 16 6 8 6 14 60 10 18 — 6 16 116 18 96 11 12 6 19 6 21 32 200 96 19 99 Total. 6,383,3^9 4,969,915 5,280,226 5,213,593 2,180,908 2,521,230 •_« Average net weight of » bale of Bengal 150 lbs. ; China Raw 102 lbs. ; Chinese Thrown 119 lbs Italian V90 lbs. ; and a ballot of Pertiao 15 Ibe. Brutia 300 lbs. ; • Ist January 1851- du. 1859 -The Stock of China of 1,118.138 lbs. is estim.-»fed at 119,112 lbs. sold, and 33^966 lbs. unsold, do. do. 1,153,650 lbs. 964,128 lbs. 198|922 lb*. la the Import of Brutia are included 19,260 lb. of a superior sort, from 19*. 6rf to 91* M do. Chm Chew are included 6,080 ofKohratsilk 4 a — * do. do. do. 9,600 of China Tusah 6 — Unsold 8,460 Iba. do. none. do. none. An Estimate of the Annual Quantities of Silk produced or exported from the several Countries in the World, exhibiting also the Countries to which exported. iVb^c— These estimates exclude the silk manufactured in Italy. Countries whence exported. Italy exports - - . . France produces - - . India and Bengal export Persia " China " Asia Minor " Levant, Turkey, and Ar- chipelago export - - Spain " Total . - Quantities. « ( n^ kils., or ( 128^ Vienna lbs. 162 lbs. English. 34,000 bales of 225 small lbs. 10,500 9,500 7,500 4,000 3,500 8,500 1,500 Countries to which exported. 74,000 bales. ) England - 5 France - - Prussia - - Russia - . Austria and Germany Switzerland Total - Qnantitiee. Bales. 28,000 22,000 7,600 6,400 5,000 6,000 74"^" State of the "Warehouses in London, ending December 31, 1850 and 1851. Bengal ...... " Liverpool ... China " Liverpool - . . Canton " Liverpool ... Chinese Thrown .... " Liverpool ... Total - * Included in China, but the quan- tity very small. Sold Stock. Unsold Stock. 1 Delivered in Dec. 1850. 1851. 1850. 1851. 1850. 1851. Bales. 4,286 7,376 • » 234 Bales. 3,067 7,698 25 1,134 233 Bales. 2,3W 13 3.157 52 • lo4 Bales. 3,715 1,675 232 Bales. 683 1,542 * 32 Bales. 608 1,752 92 185 138 11,896 12,157 5,696 5,622 2,257 2,775 snx 619 Average Monthly Deliveries from the Warehouses in London, from Ist Jan. to Slst Dec xn the Years 1849, 1850, and 1851 (including Liverpool). Bengal - - - China - - . China Thrown 1849. 715 Bales per Month 72 " " 46 " " 1850. 780 Bales per Month 1608 " " 81 " " 1851. 718 Bales per Month 1784 " « 60 " ** The following is an Account of the Exports of Silk of British Produce and Manufacture. Quantities. Declared Value. 1850. 1861. 1860. 185L Manufactures of silk only : — Stuffs, handkerchiefs, and ribbons .... lbs. Stockings doz. pair All other descriptions - value Of silk mixed with other materials : — Stuffs, handkerchiefs, and ribbons . - - - lbs. Stockings doz. pair All other descriptions - value 419,366 12,269 766,358 4,143 436,301 15,986 748,694 4,971 £ 487,450 20,261 174,879 832,140 8,153 23,102 £ 534,418 26,557 194,987 847,886 4,651 26,432 Total ....... Silk thrown .... lbs. Silk twiat and yam . . lbs. 69,993 474,349 72,460 389,901 1,040,985 63,278 161,883 1,134,931 67,803 138,685 Total • . 1,255,641 1,881,369 V. * ,1^ . ^yT, for angling, is made as follows .--Select a number of the best and largest silkworms, just when they are beginning to spin; which is known by their refusing to eat, and havmg a fine silk thread hangbg from their mouthi Immerse them m strong vinegar, and cover them closely for twelve hours, if the weather be warm, but two or three hours longer, if it be 6ooL When taken ou tod 1268 (XSIimilQD ^^SBfiHElID / / o o u o- .a O o / / y /I / / \ \ s =7Nk s. pulled asunder, two transparent guts will be observed, of a yellow green colour aa fhlr-V a. a small straw, bent double. The rest of the entr'aUs reCbTes^Sfled sp^^^ therefore can occasion no mistake as to the silk-gut. If this be soft, or break u^n I i . , 620 SILVER i i stretdiing it. it w a pm>f that the worm has not been long enough under the influence of the vinegar When the gut 18 fit to draw out. the end of it fa to be dipped into the vinegar, and the other end is to be stretched gently to the proper length^^When thus ?n'ni.^,"in fhf "ni ^^ f ^K^^ '^^f ^'^. ^^ a thin piece of boarcf by putting its extremities n^rv Tl!«l!n • u "^T^' ""' ^'•^"o"^ ^^^'V^ P'°'' ^"^ ^hen exjosed in the sun iLZ'd. I!p X« "^ ' ^"^f " ""^^^ '" ^Pf °- ^'•^"^ ^^ °^*°°^^ i" ^hict it is dried, the ends are always more or. less compressed or attenuated.* Fia. 1268 a is the silk- Z^t'^n'L Vf'^ *T° ^r^"' '. ^' '' *^^ ^"^' ' ^ ^' * ^^^^ «"t ^t the ends, with th. ^oTrVrS^' Z'-^' ^^^"^^ ^'^^ wooden pegs, for the same purpose. blLVER (Argent, Fr. ; /Si/6er. Germ. ;) was formerly called a perfect metal because heat alone revived its oxide, and because it could pass unchangoj through fiery tS which apparently destroyed most other metals, the distinctions, perfect ir^perfec?' and noble, are now justly rejected. The bodies of this class are all equal in nSuc wh,Vh^'^'\^T^ ""^"^"^ merely with different relations to otlier forms of mluen which serve to characterize it, and to give it a peculiar value. ' \yhen pure and planished, silver is the brightest of the metals. Its specific cravitv in the ingot is 10-47 ; but, when condensed under the hammer or !n the coining pfe^H ^Trcp vf ^Tt^'' ^l ^ ^"^^^ '"^ ^'^'^ " temperature estimated by somf a's eq^ii L «^- f f.^'^-,^'^^ ^y «^^^^s to 22° Wedgewood. It is exceedingly malleable and Zt^ h^ufl^u' "'' °^'' '''" tWo ^^ ^ ^"^^ ^^^^^' «"d ^^^ f^ fi»er than a W«^'J.; r ■ ^ ' i'"" *^^* '^J^^' ^fl '"termediate strength between these two metals. .!^^ T^^"*" ^'' ^^''^^ """t affect silver, but that of houses impregnated with sulrhurl eted hydrogen, soon tarnishes it with a film of brown sulphuret. It is distinguished ^iZhfrlZ^ f ' r*^' platinum by its ready solubility in nitric acid, and frolJl'aW all other metals, by its sahne solutions affording a curdy precipitate with a most minute quantity of sea salt, or any soluble chloride. / f i^ c wim a most minute Silver occurs under many forms in nature : — J. Native silver possesses the greater part of the fcbove properties; yet, on account of Its being^more or less alloyed with other metals, it diff-ers a litUe in malkabiUty Tstre pnli'^'^'J""-, Jt/«°^^tim^s occurs crystallized in wedge-form octahedrons, ncub^? ^^J}'^^^^^^/ons. At other times it is found in dendritic shapes, or arWescence? resulting from minute crystals implanted upon each other. But more usually it preS Inagnimde ^'''"' ''"^'"' determinable form, or in amorphous masses of wfoul The gar/gtt« (mineral matrices) of native silver are so numerous, that it may be said S nS '" ^" .^'"^' °^ '^'^'•. ^^ T".'^^ '' "PP^«^^ ^^ i^ filtered' into thdrfissures; at another as having vegetated on their surface, and at a third, as if impasted in thS substance. Such varieties are met with principally in the mines of Peru fh«t nf^T^Un® metal is found in almost all the sUver mines now worked; but especially ia that of Kongsberg in Norway, m carbonate and fluate of lime, &c. ; at Schl^genl^£ m Siberia, m a sulphate of baryles; at Allemont, in a ferruginous clay, &c.i^ljf article Mines, I have mentioned several large masses of native silver that have been discovered m various localities. i*iai imvc u^r The metals most usually associated with silver in the native alloy are cold conner arsenic, and iron. At Andreasberg and Guadalcanal it is alloyed with about 5 ner J^? of arsenic. The auriferous native silver is the rarest ; it has I brals-Jeffow coW ^ 2. ^nhnjoniaZ «/rer.-This rare ore is yellowish-blue ; destitute of malleability • even very brittle; spec. grav. 9-5. It melts before the blowpipe, and afl-ords whhe fumeso? o^de of antmiony ; being readily distinguished from arsenical iron anTarsenicayTobalt antimoir '"^' ""^ ^^'^ ^^ ^"^ ^ ""^ '^^^'' «"^ from 24 to 16 of 3. Mixed aniimonial saver.^At the blowpipe it emits a strong garlic smell Its con 4. Sulphuret 0/ stlver.^This is an opaque substance, of a dark-gray or leaden hue- •hghUy malleable, and easily cut with a knife. wL.;i it' betrays a meSbc lustre The bl7xplHrn[-Tr87 aJe?h T'T " """^^^ ''^ '' '' sulphur ?o 89 of silver Dy experiment , 13 to 87 are the theoretic proportions. Its spec. grav. is 69 It occurs cjTstallized m most sdver mine«, but especially in thoee of Frefberg Jo^himsthd " Bohemia, Scheranitz in Hungary, and Mexico. J' "^'^> ^oacnimstnai m 86^of1uver^^^"''^ '•^"^'"'''' '^^"^ ^^'^'-^^ «Pec. gray, is 6-7. It contains from 84 to i'i^;.f'';?'^T/"''^*f*^*'r..V'''-* *»*^f ^'~It9 constituents are, lead 36, bismuth 27 silver 15, sulphur 16, with a httle iron and copper. It ia rare. "'»"*uia ^<, aiiver • Nobb's Art of Trolling. SILVER. 621 7. ^niimoniated sulphuret of stiver, the red silver of many mineralogists, is an ore remarkable for its lustre, color, and the vanety of its forms. It is friable, easily scraped by the knife, and affords a powder of a lively crimson red. Its color in mass is brilliant red, dark red, or even metallic reddish-black. Jt crystallizes in a variety of forms. Its constituents are, — silver from 56 to 32 ; antimony from 16 to 20 ; sulphur from 11 to 14 ; and oxygen from 8 to 10. The antimony being in the state of a purple oxyde in this ore, is reckoned to be its coloring ))rinciple. It is found in almost all silver mines; but principally in those of I'reyberg, Sainte-Marie-aux- Mines, and Gua- dalcanal. 8. Black sulphuret of silver, is blackish, brittle, cellular, affording globules of silver at the blowpipe. It is found only in certain mines, at Allemont, Freyberg ; more abun- dantly in the silver mines of Peru and Mexico. The Spaniards call it iiegrillo. .. 9. Chloride of silver, or horn silver. — In consequence of its semi-transparent aspect, its 'Yellowish or greenish color, and such softness that it may be cut with the nail, this ore has been compared to horn, and may be easily recognised. It melts at the flame of a candle, and may be reduced when heated along with iron or black flux, which are distinctive characters. It is seldom crystallized ; but occurs chiefly in irregular forms, sometimes covering the native silver as with a thick crust, as in Peru and Mexico. Its density is only 4*74. Chloride of silver sometimes contains 60 or 70 per cent, of clay ; and is then called butter-milk ore, by the German miners. The blowpipe causes globules of silver to sweat out of it. This ore is rather rare. It occurs in the mines of Potosi, of Annaberg, Frey- berg, AIMmont, Schlangenberg, in Siberia, &c. Mix 1 part ot it, with 1 o! powdered charcoal, and 2 of nitre, and project the mixture fapidl^ i» small successive portions into a redhot crucible, and maintain the fused metal in ignition for a quarter of an hour. 10. Carbonate of silver, a species little known, has been found hitherto only in tht mine of S. Wenceslas^ near Wolfache. Table of the Quantities of Silver brought into the Market every year, on an average, from 1790 to 1802. Old Continent. Lbs. Avoird. New Continent. Lbs. AToird. ASIA. Siberia - . 38,500 Central America - 1,320,000 EUROPE. Hunarary . 44,000 South America - 605,000 Austrian States - . 11,000 Hartz and Hessia • 11,000 Saxony - . 22,000 Norway - - 22,000 Sweden - -) France - -> 11,000 Spain - - - ) Total of the Old Continent Total of the New Continent 159,500 1,925,000 Thus the New Continent furnished twelve times more silver than the old. For more detailed statistics of silver, see the end of the article. The following is Mr. Ward's description of the treatment of silver ores in Mexico:— " After returning from San Augustin," says he, " I passed the whole of the after noon at the hacienda (melallurgic works) of Salgado, in which the ores of the Valenciana mine are reduced. The hacienda, of which a representation is given below, fg. 1001, contains forty-two crushing-mills, called arrastres, and thirty-six stampers. The ore, on being extracted from the mine, is placed in the hands of the pepenadores, men and women, who break all the larger pieces with hammers, and after rejecting those in which no metallic particles are contained, divide the rest into three classes" (inferior, middling, and rich). "These are submitted to the action of the morteros (stamps), one of which, of eight stampers, is capable of reducing to powder ten cargas of ore (each of 350 lbs.) in twenty-four hours. This powder not being thought sufficiently fine for the quicksilver to act upon with proper effect, it is transferred from the morteros to the arra^tres (crushing-mills, see wood-cut), in which water is used. Each of these reduces to a fine impalpable metalliferous mud, six quintals (600 lbs.) of powder in !' X 622 SILVER. 24 hours. At Guknajuato, where water-power cannot be obtained, the arrastrea are worked by mules (see yi^ 1001), which are kept constantly in mot on a^T^Iow pace, and are changed every 6 hours The grinding-stones, as well as the sides ^d bottom of the mni itself, are composed of granite; four blocks of which revolve in each crushmg-mill, attached to cross-bars of wood. This part of the operation is thought of great importance, for it is upon the perfection of the grinding that the sav n- of fhe quicks.lver is supposed in a great measure to depend, in the subsequent amal "amation! The |rmd.ng is performed usually in a covered shed or gallery, which in a lar^e Aa"S 1269 The Gallera of the Hacienda of Salgado, in C^Si^*^ T J?Jr^"* 1 ^^^r"^^ ^""'^^"^ apparatus used at the lavaderos, or gold washings, m Chile. The streamlet of water conveyed to the hut of the gold washer, is received upon a large rude stone, whose flat sur- face has been hollowed out into a shallow basin, and in the same manner into 3 or 4 others in suc- cession ; the auriferous particles are thus allowed to deposite them- selves in these receptacles, while the lighter earthy atoms, still .bom three feet in diameter, \u^i\.^^^^,f'^-?^Tlf:^^'''^''^"'""' ^""' spherical boulder of syenitic eranite alSjut twn r^.. ■ / ^^V ?'""* '* " '"«* i«rt two iron Dlii»q flT.H ™„ ". i' . l-v •'"' '" d'ameter, havinij on its upper ^^r^'hTrirn^'^! lttxr^^^ZT^vc::f,'t\ !""""? °^ ""'^' » ^t"- Ihe extremities of this lever, work it ud andTwn =i? , (°*' '""^ ' '"" '"'^" '^^'^ '"' rollin" motion whi^h !.»,;?[:!!•. I "^ u T" ^"erna'elv, so as to give to the stone a ?he' washes lh"s,?ord!trsl:cS tZ'^.V"' "r^ """•"""' ^"""^ '•■'"•™','' "i 3 ucu ucAieriiy , ana it there were much gold to be separated, it SILVER. 623 1271 would afford very profitable employment; but generally the small quantity collected is sufficient only to afford subsistence to a few miserable families. The trapichCj ingenio, or mill, for grinding the ores of silver, is a verj- simple piece of mechanism. A place is chosen where a small current of water, whose section wiU present a surface of six inches diameter, can be brought to a spot where it can fall per- pendiculariy ten or twelve feet; at this place a well is built of this depth, about 6 feet in diameter ; m its centre is fixed an upright shaft, upon a central brass pin ; it is con- fined above by a wooden collar. A little above its foot, the shaft has a small wheel affix- cd to It, round which are fixed a number of radiating spokes, shaped at the end somewhat like cups, and forming altogether a horizontal wheel, four feet in diameter. Upon the slanting edges of the cups, the water is made to strike with the force it has acquired in felling down a neariy perpendicular trough, scooped out of the solid trunk of a tree This impression makes the wheel turn with a quick rotatory motion. The upri'^ht axis rises about 6 feet above the top of the well, at about half which heisbt is inserted^ small horizontal arm, four feet long, which serves as an axle to a ponderous mi. -stone of granite of from four to six feet diameter, which is made to roll on its edge in a circular trough! somt»limes made of the same material, and sometimes of hard wood. The weight of this quickly roUing stone effects the pulverization of the ore. In some cases. It is taken out in the dry state, and sifted ; but more generally the separation of tfee finely ground particles is accomplished by the action of running water. For this pjrpose a small stream is made to trickle into the circular trough, by which the jounded ore is worked up into a muddy consistence, and the finer particles flow off with lie excess of water, through a notch cut in the margin of the trough. This fine matter -» received m little pools, where tjie pounded ore is left to settle ; and the clear water being run off, the powder is re moved from the bottom, and car ried to the place of amalgamation. The ingeniosy or stamping-mills, are driven by a small breast water wheel, of five feet diameter, and one foot broad. Fig. 1003 will give a sufl5cient idea of their con- struction. The long horizontal shaft, fixed on the axis of the wheel, is furnished with 5 or 6 cams placed at different situations round the shaft, so as to act in succession on the projecting teeth of the upright rods or pestles. Each of these weighs 200 pounds, and works in a corresponding oblong mortar of stone or wood. The ;>a Tm f 624 SILVER. fine paste, is poured in. When the last or 6Uth monton is delivered, the saltierrait shovelled down and well mixed with the lama, by treading it with horses, and turning it • with shovels ; after which the preparation is left at rest for the remainder of the day. Ob the following day comes the el incorporo. After about one hour's treading by horses, the magistral or roasted and pulverized copper ore is mixed with the lama* (the repaso or ireading-mill still continuing,) in summer in the proportion of 15 cargas of 12 arrobas (25 lbs. each) to the torta, if the ore be of 6 marcs to the monton, and in winter in only half the quantity. For it is a sinrrular fact, that in summer the mixturr cools, and equires more warmth; while in \ r.Ler it acquires of itself ad'iiior ! heat. With jiooier ores, as for instance those ol 4 marcs to the monton, 12 carg;i> uio applied in summer, and 6 m wmter. From November to February, lime is also occasionally used to cool the lama, m the proportion of about a peck per monton. The repaso, or treading out, is continued by six horses, which are guided by one man, who stands in the lama, and directs them all by holding all their long halters. This operation is much more eflectual in a morning than an evening, and occupies about five or six hours. When the magistral is well mixed, the quicksilver is applied by being sprinkled through pieces of coarse cloth doubled up like a bag, so that it spurts out in very minute particles. The second treading of the horses then follows; after which the whole mixture is turned over by six men with wooden shovels, who perform the opera- tion m an hour. The torta is then smoothed and left at rest for one entire day, to allow the incorporation to take place. It unaergoes the turning by shovels and treading by horses every other day, until the amalgamator ascertains that the first admixture of quick. „ silver is found to be all taken up by the silver ; and this he does by vanning or washing a small quantity of the torta in a little bowl. A new supply is then added, and when this has done its duty, another is applied to catch any stray particles of silver. On the same day, after a good repaso, the torta is removed on hand-barrows by the laborers, to the lavaderosy in order that it may receive its final cleansins. The general method of proportioning the quicksilver to the tortas, is by allowing that every marco of silver which is promised by trial of the ores as the probable produce of a monton, will require in the whole process 4 lbs. In metals of five to six marcs and a half per monton (of the average richness of Zacate- cas), 16 lbs. of quicksilver were incorporated for every monton, = 900 lbs. for the torta. On the day of the second addition, the proportion is 5 lbs. the monton ; and when the torta IS ready to receive the last dose of quicksilver, it is applied at the rate of 7 lbs. the monton, = 420 lbs. ; making a total of 1620 lbs. of quicksilver. With poorer ores, less quicksilver and less magistral are required. ^ The usual time for the completion of the process of amalgamation, is from 12 to 19 days m the summer, and 20 to 25 in the winter. This is less than a third of the time taken at some other mines in Mexico. This rapidity is owing to the tortas being spread very flat, and receiving thereby the stronger influence of the sun. In the Mexican mines, only one monton is commonly mbced at a time ; and the lama is then piled in a small conical heap or monton. Lavadero, or washing m^.— Here the prepared tortas are washed, in order to carry off the earthy matters, and favor the deposition of the amalgam at the bottom. Each vat is about 8 feet deep, and 9 in diameter; and solidly built in masonry. A large horizontal wheel, worked by mules, drives a vertical one, which turns a horU Eontal wheel fitted round a perpendicular wooden shaft, revolving upon an iron pivot at the bottom of the vat. To the lower end of this shaft, four cross-beams are fitted, from which long wooden teeth rise to the height of 5 fetU Their motion through the water being rapid, keeps all the lighter particles afloat, while the heavier sink to the bottom. Ihe large wheel is worked by four mules, two at each extremity of the cross-beam. Water is supplied from an elevated tank. It requires 12 hours' work of one tub to wash a torta. Eight porters are employed in carrying the prepared lama of the torta in hand- barrows to the vats. The earthy matter receives a second washin<'. The amalgam is carried in bowls into the azoguena, where it is'subjected to straining tbrough the strong canvass bottom of a leather bag. The hard mass left in the bag is 12*1^3 moulded into wedge-shaped masses of 30 lbs., which are arranged in the burning- house, ( /ig. 1273), to the number of JI, upon a solid copper stand, called hasOy hav- ing a round hole in its centre. Over this row of wedges several others are built ; and th e whole pile is called pina. Each circu- lar range is firmly bound round with a rope. The base is placed over a pipe which , . , . , ., ,. , . Jeads to a small tank of water for con- di'nsmg the quicksilver; a cylindrical space being left in the middle of theptna, to give btt egress to the mercurial vapors. SILVER. 625 A large bell-shaped cover, called capellina, is now hoisted up, and carefully .owered over the pina, by means of pulleys. A strong lute of ashes, saltierra, and lama is applied to its lower edge, and made to fit very closely to the plate on which the base stands. A wall of fire-bricks is then built loosely round the capellina, and this space is filled with burning charcoal, which is thrice replenished, to keep it burning all night. After the heat has been applied 20 hours, the bricks and ashes are removed, the luting broken, and the capellina hoisted up. The burned silver is then found in a hard mass, which is broken up, weighed, and carried to the casting-house, to be formed into bars of about 1080 ounces each. The loss of silver in burning is about 5 ounces to each bar (barra), and the loss of quicksilver, from 2| upon the good metals, to 9 upon the coarse. Molina told Mr. Miers, that the produce of the galena ores of Uspaltata did not average more than 2 marcs per caxon of 5000 lbs., which is an excessively poor ore. The argen- tiferous galena ores of Cumberland afford 11 marcs per caxon ; while tlie average produce of the Potosi silver ores is only 5 or 6 marcs in the same quantity. These comparisons afibrd the clearest evidence that the English mode of smelling can never be brought into com petition with the process of amalgamation as practised in America. Humboldt, Gay Lussac, Boussingault, Karsten, and several other chemists of note, have offered solutions of the amalgamation enigma of Mexico and Peru. The following seems to be the most probable rationale of the successive steps of the process : — The addition of the magistral (powder of the roasted copper pyrites), is not for the purpose of disengaging muriatic acid from the sea salt {saltierra), as has ^^een supposed, since nothing of the kind actually takes place; but, by reciprocal or compound affinity, is serves to fbrm chloride of copper, and chloride of iron, upon the one hand, and sulphate of soda, upon the other. Were sulphuric acid to be a«««l instead of the magistral, as certain novices have prescribed, it would certainly prove injurious, by causing muriatic acJJ to exhale. Since the ores contain only at times oxyde of silver, but always a great abundance of oxyde of iron, the acid would carry off both partly, but leave the chloride of silver in a freer state. A magistral, such as sulphate of iron, which is not in a condition to generate the chlorides, will not suit the present purpose ; only such metallic sulphates are useful as are ready to be transformed into chlorides by the saltierra. This is pe- culiarly the case with sulphate of copper. Its deuto-chloride gives up chlorine to the silver, becomes in consequence a protochloride, while the chloride of silver, thus formed, is revived, and amalgamated with the quicksilver present, by electro-chemical agency which is excited by the saline menstruum; just as the voltaic pile of copper and silver is rendered active by a solution of sea salt. A portion of chloride of mercuiy will be simul- taneously formed, to be decomposed in its turn by the sulphate of silver resulting from the mutual action of the acidified pyrites, and the silver or its oxyde in the ore. An addition of quicklime counteracts the injurious efl'ect of too much magistral, by decom- posing the resulting sulphate of copper. Quicksilver being an excellent conductor of heat, when introduced in too great quantities, is apt to cool the mass too much, aad thereby enfeebles the operation of the deuto-chloride of copper upon the silver. There is a method of extracting silver from its ores by what is called imhibitum. This is exceedingly simple, consisting in depriving, as far as possible, the silver of its gangue, then melting it with about its own weight of lead. The alloy thus procured, contains from 30 to 35 per cent, of silver, which is separated by cupellation on the great scale, as described under ores of lead. In this way the silver is obtained at Kongsberg in Norway. The amalgamation works at Halsbriicke, near Freyberg, for the treatment of silver ores by mercury, have been justly admired as a model of arrangement, convenience, and regu- larity ; and I shall conclude this subject with a sketch of their general distribution. Fig, 1274 presents a vertical section of this great tisine or hiittemverk, subdivided into 1274 5. y./-A/- ^ ^^^^^'''^^ i^mm four main departments. The first, a, b, is devoted to the preparation and roasting of Ae matters intended for amalgamation. The second, b, c, is occupied with two successive 626 SILVER. p.ra.us is placed, where ii.el^"Z.MyVi.'eJ' '^""'' "' "- ""^ ■"='"""« "^ chambers of sublimaK 4 / r ^^^'^^>.^^ ^^« calcmmg area. Above the furnace ar« thp^fin« *''^ *^ivision B, c, we have rf, the floor for the coarse siftin«' • beneath that fnr At D th. rr.n!. ., J r ^ ■■ "'".'^ ''™''' '" ""^ transported to the amaJsamation casks, Sinner iron l!^ A 7 'TT^^ u^fx" (ppeissglanzsilber), bismuth, sulphurets of arsen'l ih^f^th ' : r^ ^''?^^^' ''°^'*^^>' ^^"<^* w^^h several earthy m nerals. It is essentS !£a h^v""''' *^**' amalgamated shall contain a certain proporSn of silphur In order that they may decompose enough of sea salt in the roast n- to di4n4 "e as mnrh chlorine as to convert all the silver present into a chloride Wit! ths^ew ores no^r ThP n^r"n T TA^ ""''^ .'^^^" ^''^^ ^'^ "<^^^^' ^o make upa detemSe avem^e HelZlCm^lLZZ ^i? ''^■'?'"^' '\'' rectangular heap', aboutTr efls lonTa'nd hJ^I r ?, ^ n ^ . ^^^ ^^^' a"^ "PO'^ tJ^at layer the requisite quantitv of salt i^ }Jt 4SS^L'rof'rre'"Vhe7:an'^^^ %"^"'^"- 1""^^ •' '' '^'- ofsalttlif, aTlott d t'o mast be ihPn will 1^ ^J^ap being made up with alternate strata to the desired magnitude from 3Mo dLw^ T^' ^""^ ^T"^ ^"'° ?"'"". *^'"^^' ^«"^^ ro«,^po,/,, weighing each ^VbylhrPri^^^^^^^^^^ ^' ^'' ^' Halsbrucke^ 6000 cwts.^, it iS Ihe^Te n?s^lt^7?hf '"'''T ^^^*— ^he furnaces appropriated to the roasting of ine ore-posts are of the reverberatory class, prov ded with soot chambers Th^v .rl built up alongside of the bed-Jioor, and connected with i^ b^ a br ck unnd Vh^ fuTr^rivrthen^thi^^^^^^^^ n^rV^^ helnSfandSwi^htcesJan lurmn^ over , men the hre is raised so as to kindle the sulphur, and keen the nrp rpdhnt I^d w^r re Sd'Thl d'^^f i''"^; '"" -5i^-^-y -^^^^^^ fl«m7 Thf/ exhaled. The desulphuration next begins, with the appearance of a blue m^s is Jmoerv ?u7nef n''''' ''T' t'""^^ ^'^^^ ^"^^ ^^^^^'^^ is kept up ; and he ^l^L w! ^ turned over, m order to present new surfaces, and to prevent anv ^king. Whenever sulphurous acid ceases to be formed, the finishin^^calcinat^on is^J be commenced with increased firing ; the object being now to decompose thesea salt b? means of the metallic sulphates that have been generated, to converT?hem into ebbtides' iml^he Vrfs tXX'^^^^^^ T»^^ stirring isl'becoSS of m„HrH?li Tk-^ ^^*'*'' ""* ^°"^^'' betray the smell of sulphurous, but only of muna ic acid gas. This roasting stage lasts commonly three quarters of an hour 13 or 14 furnaces are worked at the same time at Halsbrucke j and each turns out in a SILVER. 627 week 5 tons upon an average. Out of the nichi chambers or soot vaults of the furnaces, from 96 to 100 cwts. of ore-dust are obtained, containing 32 marcs (16 lbs.) of silver. This dust is to be treated like unroasted ore. The fuel of the first fire is pitcoal ; of the finishiag one, fir-wood. Of the former 115^^ cubic feet, and of the latter, 294^, are, upon an average, consumed for every 100 cwts. of ore. During the last roasting, the ore increases in bulk by one fourth, becomes in conse* quence a lighter powder, and of a brown color. When this process is completed, the ore is raked out upon the stone pavement, allowed to cool, then screened in close sieve-boxes, in order to separate the finer powder from the lumps. These are to be bruised, mixed with sea salt, and subjected to another calcination. The finer powder alone is taken lo the millstones, of which there are 14 pairs in the establishment. The stones are of gra- nite, and make from 100 to 120 revolutions per minute. The roasted ore, after it has passed through the bolter of the mill, must be t£ impalpable as the finest flour. The Amalgamation. — This (the verquicken) is performed in 20 horizontal casks, arranged in 4 rows, each turning upon a shaft which passes through its axis ; and all driven by the water-wheel shown in the middle of ^g. 1006. The ca^s are 2 feet 10 inches long, 2 feet 8 inches wide, inside measure, and are provided with iron ends. The staves are 3| inches thick, and are bound together with iron hoops. They have a double bung-hole, one formed within the other, secured by an iron plug fastened with screws. They are filled by means of a wooden spout terminated by a canvass hose ; through which 10 cwts. of the bolted ore-flour (erzmehl) are introduced after 3 cwts. of watei have been poured in. To this mixture, from | to | of a cwt. of pieces of iron, l^ inch square, and | thick, are added. When these pieces get dissolved, they are replaced by others from time to time. The casks being two thirds full, are set to revc^ve for If or 2 hours, till the ore-powder and water become a uniform pap ; when 5 cwts. of Quicb> silver are poured into each of them. The casks being again made tight, are put in gear with the driving machinery, and kept constantly revolving for 14 or 16 hours, at the rate of 20 or 22 turns in the minute. During this time they are twice stopped and opened, in order to see whether the pap be of the proper consistence ; for if too thick, the globules of quicksilver do not readily combine with the particles of ore ; and if too thin, they fall and rest at the bottom. In the first case, some water must be added ; in the second, some ore. During the rotation, the temperature rises, so that even in winter it some- times stands so high as 104® F. The chemical changes which occur in the casks are the following : — The metallic chlorides present in the roasted ore are decomposed by the iron, whence results muriate of iron, whilst the deutochloride of copper is reduced partly to protochloride, and partly to metallic copper, which throw down metallic silver. The mercury dissolves the silver, copper, lead, antimony, into a complex amalgam. If the iron is not present in sufficient quantity, or if it has not been worked with the ore long enough to convert the copper deutochloride into a protochloride, previously to the addition of the mercury, more or less of the last metal will be wasted by its conversion into protochloride (calomel.) The water holds in solution sulphate of soda, undecomposed sea salt, with chlorides of iron, manganese, &c. As soon as the revivification is complete, the casks must be filled with water, set to revolve slowly (about 6 or 8 times in the minute), whereby in the course of an hour, or an hour and a half at most, a great part of the amalgam will have collected at the bot- tom ; and in consequence of the dilution, the portion of horn silver held in solution by the sea salt will fall down and be decomposed. Into the small plug in the centre of the bung, a small tube with a stopcock is now to be inserted, to discharge the amalgam into its appropriate chamber. The cock must be stopped whenever the brown muddy residuum begins to flow. The main bung being then opened, the remaining contents of the casks are emptied into the wash-tun, while the pieces of iron are kept back. The residuary ore is found to be stripped of its silver within s or _I- of an ounce per cwt. The emptying of all the casks, and charging them again, takes 2 hoars ; and the whole process is finished within 18 or 20 hours ; namely, 1 hour for charging, 14 to 16 nours for amalgamating, I^ hour for diluting, 1 hour for emptying. In 14 days, 3200 cwts. of ore are amalgamated. For working 100 cwts. of ore, 14^ lbs. of iron, and 2 lbs. 121 ounces of mercury are required ; whence, for every pound of silver obtained, 0*95 of an ounce of mercury are consumed. Trials have been made to conduct the amalgamation process in iron casks, heated to 150° or 160° Fahrenheit, over a fire ; but, though the de-silvering was more complete, the loss by mercury was so much greater as to more than counterbalance that advantage. Treatment ^ of the jlmalgam. — It is first received in a moist canvass bag, through which the thin uncombined quicksilver spontaneously passes. The bag is then tied up and subjected to pressure Out of 20 casks, from 3 to 3i cwts. of solid amalgam are thus procured, which usually consist of 1 part of an alloy, containing silver of 12 or 13 loths (in J 6), and 6 parts of quicksilver. The foreign metals in that alloy are, copper, lead. u 628 SILVER. Wv. i i gold, antimony, cobalt, nickel, bismuth, zinc, arsenic nnil ir«n tv cu j j i n contains moreover 2 ti 3 loths of siJverIn the c^ ' "' ^^® ^^^'^ qnicMref 1275 A basis ^; b is an open basin or box of '"* fast iron, laid in the wooden drawer ; y is a kind of iron candelabra, sapported upon four feet, and set in the basin £ s under d are five dishes, or plates of wrought iron, with a hole in the centre of each, whereby they are fitted upon the stem of the candelabra, 3 inches apart, each plate being successively smaller than the one below it. 3 indi- cates a cast-iron bell, furnished with a wrought-iron frame and hook, for rais- L- mg it by means of a pulley and cord. ** Th' Tl;'*"^^^^- ^^^ ^e" has been set in its place* '" * ^^^^^^-iron door for closing the renewed'r^hrgh a'^ipeln ifZl !!f Z w^""! "^^^^' T^^^'' "^"^* ^^ -"^'"-"^ kept always submerseVand cool. The d awer . be.^n'"' '" '""T '\' 'T ^"^^" "^^^ ^ under d being char-ed with \Zu nf »^oi /' • J"^ properly placed, and the plates is to be let dolnTnto thrwater ^^ 'a^ Tand rT.,t^':^^''"fK' i°"'^*^^' ^ ^^^^'^^ '^' ^^" 3 Upon the ledge 1, which defines the boUom n/ th^r 'V ^«^^^P«'! ^^'^^ candelabra. laid, having a ho e in its middle fnrthphiT. *^^ ^f^-P^ace, a circular plate of iron is fir-wood ar'e kindled thl the dlrV'^^^^^ 'V^'f '^T^^' ^P^" ^his plate chips of The fuel is now placed i^tieva^an?^^^^^^^^^ T^ "^^^^ ^^ ^H^l «"^ J"»^^ '^^^ht. must be fed in most gradually first witrt„rf\h?nw-tK^ l^^^' y*'^ f ^^^ ^'"- "^^^ ^« red, the mercury volatilize "and ronii'-^^ v '^ charcoal ; whenever the bell gets At 'the end orS^hourshoSd n^ ^ m globules into the bottom of the basin b. the fire is stopped When "he bell has b/onL' '^ °?'^f ^"T.^i^T^ '^ ^«» ^"^^ t^** ^ater, from the candelabra d^^and this be^ ' taken ouT hi' '/ ^'^'^ '^' i^/ ""^^'''Z'' '^'""^"^ nace. The mercury s drained dr^Pd «n^ c % ^ '^•'^'^" " '' '^'^ ^^^^ ^'"^^^ ^^^ fur- The saver is fused and refinerbfc^pe^^^^^^^^ ''"' "^^''^ '"'" '^^ amalgamation works. proma^Ty'outTlrt^^yfsiu apparatus, would be distilled more 815, 816: ^ '" ^^^ mercurial retorts described and figured in pages of 16 ; one fifth paTof^h mS befng'c^^^^^^^^^^ ^-""'''f |"^ ^"^^^ «"t Of 160 or 170 marcs, in black-lead rrudEfifledwf.h-t ^^'V '^5"t^/° quantities submitted to brisk ignition Th^ ^^i? T *"'" ^^° ^^^^^^^ <^^ ^heir brims, and liquid slag, whicrbelnrskimmed off ^" ""'r ''^•^^"' f °^" ^«P^^«' ^^^^ t^^-o^s ^P a Ader, and covered wi?h a H^^ 't *° ^^ '^'^^^^ over with charcoal the charcoal LXn rrmoVed aionlw^^ been briskly urged for a short time, observe whether the vap^have of aled If n ^ fil? ^' ""V ^•^^^^'^^"^ ^^ order to the crucible must be co?erKth^^^^^^^ ""'* '^ '^^^^^ ^PP"^^' and the surface of the silver becomes tranmiirS Ik n^ ^""^^P ^°""^r produced, gold and much coppe;, beTng now frirn ^ if Z^S th f P\^?J?h <^°"t->*"« * ""le maUon,\'S?4"u^^^^^^^ being "submitted to a second amalg, with three or four per cent of a mktLl Af / ''^T' 7^'' '^ ^''^ ^"^^^ a^^"? sulphate of soda), aSd then refined Thl I ^""^^t"' ^?^'^ '^^*^^"^^ quicksalz (impure tanks in which the contents of the casks are niw!!^ ^T""' '**?' ^' '^^^^'^ ^'"^ «^ ^^^ of soda, along with some common salt sulnhitr J"'''''^'' T''''' '^''^^ of sulphate Dhosphate, a?seniate, and fluatTof soda Th! ^l 'T" ^"^ inanganese, and a litUe «f « 7n/A «r -1 . ^ ^^^ ^^r^by deposite contains from i to » LVSi^einlZZ''^'- '"' "" *"■««"-' -'">«) of extracting thi, s.,.! ,Va„u¥, •^* ' ^"' *^'°» ana iJ7y. These figures exhibit the cupellatioi SILVER. 629 furnace of the principal smelting works in the Hartz, where the following parts must be distinguished} ifig* 1278); 1. masonry of the foundation; 2. flues for the escape of moisture ; 3. stone covers of the flues ; 4. bed of hard rammed scoriae ; 5. bricks set on edge, to form the permanent area of the furnace ; 6. the sole, formed of wood ashes, washed, dried, and beaten down ; k, dome of iron plate, moveable by a crane, and sus- ceptible of being lined two inches thick with loam; w, n, tuyeres for two bellows •; having valves suspended before their orifices to break and spread the blast ; j, door for introducing into the furnace the charge of lead, equal to 84 quintals at a time; s,Jig. 1279 1279, two bellows, like those of a smith's forge ; y, door of the fireplace, through which billets of wood are thrown on the grate; x, small aperture or door, for giving issue to the frothy scum of the cupellation, and the litharge; z, basin of safety, usually covered with a stone slab, ovei which the litharge falls; in case of accident the basin is laid open to ad- mit the rich lead. The following is the mode of con- ducting the cupellation. Before put- ting the lead into the furnace, a flooi is made in it of ashes beat carefully down (see 6, Jig. 1278); and there is left in the centre of this floor a circulai space, somewhat lower than the rest of the hearth, where the silver ought to gather at the end of the operation. The cupel is fully six feet in diameter. In forming the floor of a cupel, 35 cubic feet of washed wood ashes, usually got from the soap works, are employed. The pre- paration of the floor requires two and a half hours' work ; and when it is completed, and the moveable dome of iron plate has been lined with loam, 84 quintals (cwts.) of lead are laid on the floor, 42 quintals being placed in the part of the furnace farthest from the bellows, and 42 near to the fire-bridge ; to these, scoriae containing lead and silver are added, in order to lose nothing. The moveable lid is now luted on the furnace, and heat is slowly applied in the fireplace, by burning fagots of fir-wood, which is gradually raised. Section 1278 is in the line c, D, of 1277. At the end of three hours, the whole lead being melted, the instant is watched for when n3 more ebullition can be perceived on the surface of the bath or melted metal; then, but not sooner, the bellows are set a playing on the surface at the rate of 4 or 5 strokes per minute, to favor the oxydizement. In five hours, reckoned from the commencement of the process, the fire is smartly raised ; when a grayish froth (abstrich) is made to issue from the small aperture x of the furnace. This is found to be a brittle mixture of oxydized metals and impurities. The workman now glides the rake over the surface of the bath, so as to draw the froth out of the furnace ; and, as it issues, powdered charcoal is strewed upon it, at the aperture r, to cause its coagulation. The froth skimming lasts for about an hour and a half. 630 SILVER. %§i After this time, the litharge he eins to form -«^ •» • i t x; its issue being aided by a hook In n^n' ? '' '^ ''^^'J^^ ""^ ^r ^^^ ^^'^^ openiDji pregnated with litharge, the woTktan d.V^T/*-?" "' .!^%^°^' «^ ^»»« f«™«<^e 8^^ >«n litharge; it falls in from' of the smXapertSe^l^^ the escape of thi liouid By means of the two moveable vaJve^ l!,.«l'nH» 1 ^.^""^^^^j" stalactitic forms. should be made to cause a slight curl on ihJ Kn, • i ^^ ^^^ '"«t«^- The wind lations, and gradually propel a portion of the b.h^' '"^ ^' to produce circular undu- the cupel, and allow this ?o ret^rtsshlpeur^ ^^^^rds the edges of of air should drive the greater part of the lifh«rl. . I ^u ^P^^»tion. The stream the workman deepens the ouUeffor k in nJononf 'T'n' ?^' ^:°^?" ^P^"^"^ ^> ^^ere scends, and the bottom of theToor\\tt\^?^J^ ^^- the level of the metal bath de- tharge'is thus obtained during about 2 honr^ nJ^'^^^'i'^ k ""^ '^l ^"^«^^^ ^"^'^^ ^^' gins to take shape in the cent^re of the eupel ' '"'' ^'"'^ '^' '"^^ «^ "»^'^' ^^ •lithaTcaVbe "oked for, a^ wL^n "trmTsST •''\^ '°"' .^^^^'^^'^^^ '^-'"^als of cake in the middle of the floor gTeatc^eZ/t iJfV' !^^ "^^^h^orhood of the silver because they contain silver \C thT Sd^i^^^^^^^^^^ apart the latter portions, places before the little opening x a brick inilt ^ '' ^creased, and the workman The use of this brick is i f« k- V .7 ^ ^^"^ ^^ * »""""^ to the efflux of lithar-e for example, shouWan^;;t on t^a^^^^^^ f '^' ^"^„" '" '''' '^ «"y aS-n^ i litharge, should that still cSatin^ro,n/t^ ^'^ ^"'"^'' \^' **^ '"'''"^^ « 'magazine of cupel, for in this dilemma reS/eT^^^^^^^ rakpH TX^' 'f"^'-"!^' '^^^^^^^^ ^^ the the escape of the water that Lst b^^thm^n . .if^M ^^""^ *"." *^*^ "^'^^^J 3. to prevent When^he argentif^^ouf lirarge ^^^^^^^ '^'T'^ ^^^^e procnfs. moved, it is let out in the form of a jet bv the Lit Prn^ 'V^l "?°-«^i"^' is to be re- Lastly, after 20 hours the Rllvpr S • dexterous use of the iron hook. The moment for stoppYng the fi randlhe'beTnw ' • '•' J^'l ^7^^l""^ "^^^^^ <^'^^"^". ance of the colored particles of or vdenflLHTi!' .'"^i.'^^l^^ »>y the sudden disappear- undulate with extrerrapidi?y o7er ife sll^htTv 1' '" '^' T'' T''''''' ^^ «^>'^^'ion, ing from the centre to the circumference fhJrlZ "" surface of the silver bath, mov- is called the lightning, or fiStTon Wh^n^r^^^^^ ""^ ^v^" ^^''^^ 'Jisappearance perfectly clean, there is introducedTnto th^ furnlce ^'.^7''' *^" ^^^'^ "^ ^^^^^^'^ ^^'^^ "TtrpXirn7ft'-i%^'f^^^^^^^ woTkTng 'Tie pr^^^^^^ Z'^'^f'^'T ^^!? ^^^^^ ^" ^— ^ ^^ or 20 hours' leads employed, SndSn the acre's oHe'Ltr^' Z '""t ^^^T^ ^^ Parity of tlTc of fuel. A'go'od workman co^Te es the cu'npnI?L'''r\f '"? ^'f "^^ *^^ ^^^^^'^T at.e.t^e^ofS4.uintalcha;g-oS^^^^^ The products of the charge are as follows :~ 2 Pnlfi,t>, ^"^ '" ^^9 ?""^'» "^ '"^^^^ «"d 3 loths of alloy - 2. Pure litharge, containing from 88 to 90 per cent, of lead - 3. Impure litharge, holding a little silver . 4. Skimmings of the cupellation . . ' " 5. Floor of the furnace impregnated with litharge '. I aboK quintal amiaim 116 Colopu: poundl ^ i03 pound, ttvoirdupous and ilu From numerous experiments inihe i»rpnt\r«t •. ». ' v /^^ ^" * ^°^«"" -"^ale. 100 quintals of lead can be profitlblv culTJ^^^^^ "' ^''" ^^^"'^ *^^^ "«' "^«^^ than furnace, and however pLerfufandmultS '^'T/'"^' ^"^^^'^'' '«^^^ ^^^ loss on eilher the lead or the silver or on both t i T ^""^ *"^'^','' "^^^ ^^5 for the no less than 500 quintals were acted on in ^ ^r^li^lsrr''^^' \" «"« "^^'"Pt, W«ono/ M.Z..4^^5iis r:^a-i-la-eaTJ^;;r^^^^^^^^^ Such is the train of operations by which the cupriferous galena schlich, or ground oit 24 to 30 marcs. 50 - 60 quintals. 2-6 — 4-8 — 22-30 — SILVER. 631 is reduced, in the district of Clausthal, into lead, copper, and silver. The workt of Fmnkenscharn have a front fully 400 feet long. Ftg. 1279, exhibits the plan and elevation of these sraelting-works, near Clausthal, is the Hartz, for lead ores containing copper and silver, where about 84,000 cwts. oftdUick Silver-smelting Works of Frankenacham^ near Clausthal. 128C (each of 123 Cologne pounds) are treated every year. This quantity is the prodir* of thirty distinct mines, as also of nearly as many stamp and preparation works. All these different schlichs, which belong to so many different joint-stock companies, are confound- ed and worked up together in the same series of metallurgic operations; the resulting mixture being considered as one and the same ore belonging to a single undertaking; but in virtue of the order which prevails in this royal establishment, the rights of eacn of the companies, and consequently of each shareholder, are equitably regulated. A vigorous control is exercised between the mines and the stamps, as also between the stamps and the smelting-houses ; while the cost of the metallurgic operations is placed under the ofli- cers of the crown, and distributed, upon just principles, among the several mines, ac- cording to the quantities of metal furnished by each. From these arrangements, the following important advantages flow : — 1. The poor ores may be smelted with profit, without putting the companies to any risk or expense in the erection of new works ; 2, by the mixture of many different ores, the smelting and metallic product become more easy and abundant; 3, the train of the operations is conducted with all the lights and resources of science ; and 4, the amount of metal brought into the market is not subject to such fluctuations as might prove inju- rious to their sale. The following is the series of operations; — 1. The fusion of the schlich (sludge) ; 2, the roasting of the mattes under a shed, and their treatment by four successive re-meltings ; 3, the treatment of the resulting black copper; 4, the liquation ; 5, the re-liquation iressjias;e) ; 6, the refining of the copper ; 7, the cupellation of the silver; 8, the reduction of the litharge into lead. The 5th and 6th processes are carried on at the smelting works of Altenau. The buildings are shown at a, b, c, and the impelling stream of water at d ; the upper figure being the elevation ; the lower, the plan of the works. a, is the melting furnace, with a cylinder bellows behind it ; 6, c, d, furnaces similar to the preceding, with wooden bellows, such as yig. 1281 ; «, is a furnace for the same purpose, with three tuyeres, and a cylinder bellows ; /, the large furnace of fusion, also with three tuyeres; g, a furnace with seven tuyeres, now seldom used ; A, low furnaces, like the English slag- hearths, {krummofen,) employed for working the last mattes ; fc, slag-hearths for reducing the li- tharge ; m, the area of the liqua^ tion ; n, p, cupellation furnaces. Xy y, a floor which separates the principal smelting-house into 632 SILVER. two stories; the materials acstined for charpinir «i,. r„ * . , Copper, (finally purified in the works of Alten.n,) " . " ^ Total product. - 28,564 e^ab,rhfe'nt~ht';ar"t SVu^n sh"'"" ••"^'" ""^"^^ ''^'^ '- ">« «™« ofh. bellows are constru'ctXToSy of w3t'iZm/''T',!' """"" ""' «f ■'^'h"'^''- Th« a bishop of Bamberg, a Ju, ihl yerr^'O Aflnr ^^'-''''''''ir i-nprovemen, n.ade b, were adopted, towards i730, fn^Ymos a^t^he iLeltTne wS, l!",?"' "'""fi""-^. "4 a few places, as Carniola wherp Inrai ^1 smelling- woi ks ol ihe co* jnent, except in to he erected. Thes^p C'^/a XpeTreCs"'e"^\r 'r?!-^ water blowinVmac'hi^: have, however, many imperfections • theiV size m?,T'X u "^^^*^«^'« wooden boxes, order to furnish an adequate stream nfifr fi T ^^" ^^ inconveniently larj?e, in -^^^^ l9fiQ u __^.™.^_ the seal, (^ite.) In the bottom of the p/e, there is an orifice furnish- ed with a clack-valve rf, opening inwards when the/y is raised, and shutting when it falls. In order that the air included in the capaci- ty of the two chests may have no other outlet than the nose-pipe w. the upper portion of the gi/e is pro- vided at its four sides with small square slips ofwood,c,c,c, which ^_ ^ are pressed against the sides of the b,byb, while they are retained upon the eife hv mp.nc r ^ ^V°"^ springs of iron wire, a, a, a. The latter a, a, are SratS i„ thp . . '""^^ T^'^ ^'^'^^ "^'wood, a. Stems, called bucheaes /they are'atthed, aUhefr [owe^^ ^o'^h'^^' "?^? rectanguW r/6 G. P, IS the driving-shaA of a water'wheel wMHi hv 1 ' ^^J? "^""^'^ ^^^^^ «^ the lurZes^e'i^'pioy^^^^^^ lead ores extracted from the mine of RammelsberT' See .^"^^ "i'' ^"'-^"^^^^'"^ ^^^ silvery Pig. 1283, is the front elevation of theTw in fuT;aces bun» • ""^ *" P-.^^^, Vol. 1L n,. 1284, IS a plan taken at the level of T^^i^t^ ^^/^ 't of .Tml* ^2®^ ^f*. 1285 aid 1286, exhi! bit two vertical sections? the former in the line a, b, the latter in the line c, d, of fig, 1284. In these four figures the following oh. jects may be distinguished, a, by c, dy a balcony or platform which leads to the place of charging, n ; «,/; wooden stairs, by which the charging workmen mount from the ground ;>,^, of the works, to the plat- form ; gy hy brick-work o| the furnaces; t, /c, wall -,f.^ . ■■ ■ - J ^ the smelting- worki^ OTpported J ly upper basin of reception, hollowed out of th^ h.?^***"^! "^^'""^ /^^>' "« bed,) 6; m, arch of the tuydre v. by which mcK f ^ brasqru, (ci rround charcoal »u,cic V, oy wmcli each furnace receives the blast of two SILVER. 633 bellows; n, place of charging, which takes place through the upper orifice n, o, of the basjn w, o, v, t, of the furnace; /, a slab of clay, placed in such a way that, during the ^ 1284 treatment of the lead, a liitle metallic zinc may run together in a sloping gutter, seen m fig. 1269, formed of slates ce- mented together with clay. In^gs. 1283 and 1285, 1,2-, is the brick-work of the fcon- dations; »n, conduits (called evaporatory)for the exhalation of the moisture ; 4, a layer of slags, rammed above ; 5, a bed of clay, rammed above the . . ^ , ~ J * . ^'^"^ ' ^> ^ brasque, composed •)! one part of clay, and two parts of ground charcoal, which forms the sole of the furnace. The excellent refinery furnace, or treibheerd, of Kre.leiickshutte, near Tarnowitz, in Upper Silesia, is represented in fig? 1287 and 1288. a, is the bottom, made ol slag or cinders ; b, the foundation of fire-bricks ; f, the body of the hearth prcner, composed of a mixture of 7 parts of doiomite, and 1 of fire-clay, in bulk; d, the grate of the air furnace; e, the fire-bridge; /, the dome or cap, made of iron plate strengthened with bars, and lined with clay-lute, to protect the metal from burning ; g, the door of the fireplace; h, the ash-pit; i, the tap-hole; ky ky the flue, which is divided by partition! into several channels ; Z, the chimney ; m, a damper-plate for regulating the draught ; n, a back valve, for admitting air to cool the furnace, and brushes to sweep the flues; o, tuyere of copper, which by means of an iron wedge may be sloped more or less to- wards the hearth; />, ihe schneppety a round 1286 piece of sheet iron, hung before the eye of the tuyere, to break and spread the blast; 9, the outlet for the glassy litharge. Lime-marl has been found to answer well foi making the body of the hearth-sole, as it ab- sorbs the vitrified litharge freely, without com- bining with it. A basin-shaped hollow is form- ed in the centre, for receiving the silver at the end of the process ; and a gutter is made across the hearth for running off the glatte or fluid litharge. ir"^TooP®^' ^^^^' represent the eliquation hearth of Neustadt. /• -.J- *^'* *^''°^^ ^^*^^^°" 5 fiS' 1290 is a front view; and^g. 1 291. a longitudinal section. It is formed by two walls «, a, ^ feet hi-h placed from I to 1 foot apart, sloped off at top with iron plates, three inches thick, and 18 inches broad, called saigers-char" teUy or refining plates, by by inclin- ed three inches to- wards each other in the middle, so as to leave at the low- est point a slit two and a half inches wide between them, through which the leed, as it sweats out by the heat, is allowed to fell into *"""■■""■"■"■" 634 SILVER. the space between the two walls c, called the jt/»»v#^«.«..- , a crucible or poi. Up- on one of the long sides, and each of the shorter ones, of the heartli, the walls rf, d, are raised two feet high, and up- on these the liquation lumps rest; upon the other long side, where there is no wall, there is an opening for ad- mitting these jumps in- lo the hearth. The openings are then shut with a sheet or cast iron plate «, which, by _ means of a chain, pul- may be easily raised and lowered r J= « «» r • . ^^^' *"^ counterweight, . \ ""* r^r . oo/' ^ ? passage for increasing the draught of air. rickshut e by Tarnowilz; a, is the fire door; 6, the grate- r The door for introducing the silver; d, the inoveable\est,festing ipon but thki AnJ -^ ^'\ ^""^^^ ^^^" ^^"'^ ^^^»" to be necessary ; bu this IS done in order to be able to place the surface of the if A/^l M* ^'^rT^y^ ^^ ^"^' ^'^^' For Ihi'refinins of JOO marks cubic feet of pit-coal are rlqS ' The 11"'"'^' ^', '"' ^°i^^ (half ounces) per cw^S silver and soft lead are pinntoii '"' '"^'^ "'"'^ '^^ ^"^^^'^ ^^^°^^ ^^"^ ^'"P"^ At these smelting-houses, from 150 to 160 cwts. of very pure v^UW lead (lead con- ^_I290 ^ J291 SILVER. 63S .Uoy containing f„n. uj lo-'lsT.Tr ff iLtXr ""efcm.'Js S„T ""'' ""'" '" 1292 1293 fireplace is 22 inches squarerrnd s «™ratS Z„ r"''/.«'- ^P* ""^ !-«». ^"h"* in breadth. The flame, after having S3 o^er .h^ ""r '"'* X» fi"-Wdge, 14 inche. ters two flues e, e, on the onTO^he s?de o^lh. f^^ ^"'i^'v '"^"'* '«»'' '"">« «"Pel, en- f, .-, 40 feet high. At the bK nf ,h! lill "=^' "^""' '«™i"»'e '" a chimney t L Ulfic dust de^sited withiSr'%"hefe „pen'r47re"irduri^^{i,''' *■"' """"'»"' '"^ "»^ The cupel or test, which constitulL, n' fact* fhe ™"e oY Jh7 ll"?.; • ... operatton take, place, is moveable. I, consi:^", "S Tver Li' d 1;^ rinf^f'^ n *u««jca* .fc . TOUT iron oars (a, d, m, m, b, c, n, n) are fixed across iti 1294 u-^ „„H ,m,i . bottom, which are also 3| inches broad, and an inch thick. The first of these bars is placed 9 inches from the end of the elliptic ring nearest the fireplace, and the three others ai2 equally distributed be- tween this bar and the back end. In forming the cupel, several layers of a mixture of moist- ened bone ashes, and fern ashes, in very fine powder, are put into the test-frame. The bone ash con- stitutes from I to 1 of the bulk of the mixture, according r I- ,,..,, to the purity of the rem ashes employed, estimated by the proportion of potash they contain, which has the property of semi-vitrifying the powder of burnt bones, of thus removing its friability, and 1296 „ _!* .m_ „ joqY C ^_ Vi. renderms It more durable. The layers of ashes are strongly beat down, till the frame is entirely filled. The mass thus formed is then hollowed out by means of a little snade made on purpose, till it is only three quarters of an inch thick above the iron bars near the centre of the bottom. A flange, 2 inches broad, is made at the upper part, and 2i inches at the lower part, except on the front or breast, which is 5 inches thick In thb anterior part, there is hollowed out an opening of an inch and a quarter bro'ad, and 6 inches long, with which the outlet or gateway of the litharge communicates The cupel thus prepared is placed in the refining furnace\ It rests in an iron ring buUt into the brickwork. The arched roof of the furnace is 12 inches above the cupel n?ar"he fire-bridge, and 9 inches near the flue at the other end is JlL^rdlroV^K '" '*"" ^''^ "^ '^' ^''™^''' °^P"'^'" '^ '^' '^' *' ^^'^^^ '^' ^'^^S^ dud^gldted kid"" ^'^ *' '^' '^'' ""^ '^"^ '"P'^' '^'^'' ^'' ^"""^'^^ ««" ^' ^^' ^""^ Refining of lead to extract its silver.--This operation, which the leadof Derbvshirecan- not be submitted to with advantage, is performed in a certain number of the smelting- houses at Alston-moor, and always upon leads reduced in the Scotch furnace The cupel furnace above described must be slowly heated, in order to drv the cunel '^tHe'JZi:iVL%''"^xk'^^^\'^''''i:^ infallibly be produced by sudden 7vaporati^ of the moisture m it. ^ Whenjt has been thus slowly brought to the verge of a red heat. It IS almost completely filled with lead previously melted in an iron pot. The cupel may be charged with about 5 cwts. At the temperature at whicn the lead is in- troduced. It IS immediately covered with a gray pellicle of oxyde; but when the heat of the furnace has been progressively raised to the proper pitch, -t becomes whitish-rcU, and has its surface covered over with litharge. Now is the time to set in action the blowing-machine, the blast ot which, impelled in the direction oi u.e crcat axis ol th* cupel, drives the litharge towards the breast of the cupel, and makes it flow out by the 7t li 636 SILVER. ?2.^r ??^ ^' '^' l^^^J^ 7^'^^ 'i ^^"' ''^'' "" *^^^*-»^«" P'«te, on a level with th« floor of the apartment, and is dispersed into tears. It is carried in this state to the fur- nace of reduction and revived. As by the effect of the continual oxydization which it anderg^oes, the surface of the metal necessarily falls below the level ofThegat^iy of the litharge, melted lead must be added anew by ladling it into the furnacffSL ^he iron boiler, as occasion may require. The operation is carried on in this manner till 84 cwts or 4 Newcastle /od^ier, of lead have been introduced, which S.es from 16 to 8 hours, if the tuyere has been properly set. The whole quantity of^ilver wh ch th^ mass of lead contams, s left in combination with about 1 cwt. of Lad, which uider the name of nch lead, is taken out of the cupel. * ' * When a sufficient number of these pieces of rich lead have been procured, so that br 2M0 on n^Z" r T^^'^l^^' determined by assaying, they contain in whole from 1000 to 2000 ounces of silver, they are re-melted to extract their silver, in the same furnace but ma cupel which differs from the former in having at its bottoi a depression capable of receiving at the end of the process the cake of silver. In this case a portion of Te hot- th"ed1I^s'onre*'snver '''' ^ ^^^ '*'''"* ""^^ ^^ ^"'^"^ ^'''^^ "^'^^ * ""^^ rake, from The experiments of MM. Lucas and Gay Lussac have proved that fine silver, exoosed to the air in a state of fusion, absorbs oxygen gas, and gives it out again in the act^ consolidation The quantity of oxygen thus absorbed may amount to%wen?y.two tiLei the volume of the silver. The following phenomena are observed when the mass of mTtS IS considerable ; for example, from 40 to 50 pounds. The solidification commences at the edges, and advances towards the centre The liquid silver, at the moment of its passage to the solid state, experiences a slight agination and then becomes motionless. The surface, after remaining thus tranquil for a mtle' flow fn H-f?"'" ,T^"1^''^ perturbed, fissures appear in one or several lines, from wh ch ^Jnn ^J.f '•f ^^7^-^'°^ > st'-eams of very fluid silver, which increase the original ad- tation The firs stage does not yet clearly manifest the presence of gas, and seems to arise from some intestine motion of the particles in their tendency to groip, on entmn? upon the process of crystaUization, and thus causing the rupture of the Invelop or ex S crust, and the ejection of some liquid portions. ^ exiernai .r.t^^'' remaining some time tranquil, the metal presents a fresh appearance, precisely ^;?l!f ? to volcanic phenomena. As the crystallization continues the oxy^n gas J fnTeTr nfThl^c/'?^"'''" ^' ^ • ' ""' °^°.'" C^^"^^^' ^"''^^'^S ^'^'^ ^' '^^^^^ silver from he interior of the surface, producing a series of cones, generally surmounted by a small crater vomiting out streams of the metal, which may be seen boiling violently within them ' «n J tw ^Jh-^l g'-a'l^ally increase in height by the accumulation of metal throwi up. and that which becomes consolidated on their sloping sides. The thin crust of metS on which they rest, consequently experiences violent impulses, being alternately raised and depressed by such violent agitation, that were it not for the tenacity and elasTicity fjA^'^^'^h here would evidently arise dislocation, fissures, and other anaToious accidents. At length several of the craters permanently close, while others cont!nu'e to allow the gas a passage. The more difficult this is, the more the craters become elevated, and the more their funnels contract by the adhesion or coa^u at on of a fZ\Z °^w' °''''^: J^' P^'^J^^^^'^" «*' ^^°*»"'^^ °^ «"^«^ "o^ »>ecomes more violent* i Ir^l^'r 1 ' -'"^^ ^"^ ^'^^l distances, even beyond the furnace, and accompanied by a series of explosions, repeated at short intervals. It is t^enerally the last of these little J^l'tZZ '^' '^"ains the greatest altitude, and exhibits the foregoing phenomena w"h the greatest energy. Jt is, moreover, observable, that these cones do Jot all arise at the nZl ™^'''™' ^n^ T^^^^^f' ^°'''^"' ^^^'^ others commence forming at other ppmts Some reach the height of an inch, forming bases of two or three inches in of'aTlToir. ' """''''"^ ^^ '^'' "^^•^^'^'"'^ ^^ "' ^'^'' ^'•^"^ ^^^^ »« three quJte« .K^y'lf *hf /;j™ation of these cones, by the evolution of gas, portions of silver are shot forth, which assume, on induration, a form somewhat cylindrical, and often ve^ fantastic notwithstanding the incompatibility which appears to ex trbetween th^ fluidity of the silver and these elongated figures. Their appearance is momenlarv and w.lho.rt any symptoms of gas, although it is impossible to decide whetheT they mly no' Jrar^'peiiod."'""''' '''^' ^*^^"' " ^'^^' '' ^-^^^'""^ ^^«^ P^^»°°^-- of theTj Till very recently, the only operations employed for separating silver from lead in the English smelting-works, were the following •— o * ^^ »»""i icau m loie llJ;.?Tr^^*'";i'" '^r'''^ ^^l leadvr^s converted into a vitreous oxyde, which w Ooated oH from the surface of the silver. 2. Reduction of that oxyde, commonly called lithart'e J SILVER. 637 Cupellation and its two complementary operations were, in many respects, objectiona* blc processes j from the injurious effects of the lead vapors upon the health of the work, men ; from the very considerable loss of metallic lead, amounting to 7 per cent, at least ; and, lastly, from the immense consumption of fuel, as well as from tne vast amount of manual labor incurred in such complicated operations. Hence, unless the lead were tolerably rich in silver, it would not bear the expense of cupellation. The patent process lately introduced by Mr. Paltinson, of Newcastle, is not at all pre- judicial to the health of workmen; it does not occasion more than 2 per cent, of loss ot lead, and in other respects it is so economical, that it is now profitably applied in Nor- thumberland to alloys too poor in silver to be treated by cupellation. This process if founded upon the following phenomena. After melting completely an alloy of lead and silver, if we allow it to cool very slowly, continually stirring it meanwhile with a rake, we shall observe at a certain period a continually increasing number of imperfect little crj-stals, which may be taken out with a drainer, exactly as we may remove the crystals of sea salt deposited during the concen- tration of brine, or those of sulphate of soda, as its agitated solution cools. On submit- ting to analysis the metallic crystals thus separated, and also the liquid metal deprived ol them, we find the former to be lead almost alone, but the latter to be rich in silver, when compared with the original alloy. The more of the crystalline particles are drained from the metallic bath, the richer does the mother liquid become in silver. In practice, the poor lead is raised by this means to the standard of the ordinary lead of the litharge works ; and the better lead is made ten times richer. This very valuable alloy is then submitted to cupellation ; but as it contains only a tenth part of the quantity of lead sub- jected to crystallization, the loss in the cupel will be obviously reduced to one tenth of what it was by the former process; that is, seven tenths of a per cent., instead of seven. These nine tenths of the lead separated by the drainer, are immediately sent into the market, without other loss than the trifling one, of about one half per cent., involved in reviving a little dross skimmed off the surface of the melted metal at the beginning of .he operation. Hence the total waste of lead in this method does not exceed two per cent. And as only a small quantity of lead requires to be cupelled, this may be done with the utmost slowness and circumspection ; where'by loss of the precious metal, and injury to the health of the work-people, are equally avoided. The crystallization refinery of Mr. Pattinson is an extremely simple smelting-house. It contains 3 hemispherical cast-iron pans, 41 inches in diameter, and | of an inch thick. The 3 pans are built in one straight line, the broad flange at their edge being supported upon brick-work. Each pan has a discharge pipe, proceeding laterally from one side of its bottom, by which the melted metal may be run out when a plug is withdrawn, and each is heated by a small separate fire. Three tons of the argentiferous lead constitute one charge of each pan; and as soon as it is melted, the fire is withdrawn ; the flue, grate-door, and ash-pit, are immediately closed, and made air-tight with bricks and clay-lute. The agitation is now commenced, with a round bar of iron, terminated with a chisel-point, the workman being instructed merely to keep moving that simple rake constantly in the pan, but more especially towards the edges, where the solidification is apt to begin. He must be careful to take out the crystals, progressively as they appear, with an iron drainer, heated a little higher than the temperature of the metal bath. The liquid metal lifted in the drainer, flows readily back through its perforations, and may be at any rate effectually detached by giv- ing the ladle two or three jogs. The solid portion remains in the form of a spongy, semi- crystalline, semi-pasty mass. The proportion of crystals separated at each melting, depends upon the original quality of the alloy. If it be poor, it is usually divided in the proportion of two thirds of poor crystals, and one third of rich liquid metal ; but this proportion is reversed if the alloy contain a good deal of silver. Let us exemplify, by the common case of a lead containing 10 ounces of silver per toa. Operating upon 3 tons of this alloy, or 60 cwts., containing 30 oz. of silver, there will be obtained in the first operation — (o) 40 cwts. at 4 J ounces of silver per ton ; in whole 9 oz. > on (6) 20 cwts. at 21 — -_ gl 5^"°^' Each of these alloys, (a) and (6), will be joined to alloys of like quality obtained in the treatment of one or several other portions of three tons of the primitive allov. Agaia, three tons of each of these rich alloys are subjected to the crjstallization process, and thus in succession. Thus poorer and poorer lead is got on the one hand, and richer and richer alloys on the other. Sometimes the mother metal is parted from a great body of poor crystals, by opening the discharge-pipe, and running off the liquid, while the work- man keeps stirring, to facilitate the separation of the two. 25 fodders, 15 cwts., 49 lbs. — 540 cwts., 49 lbs. of alloy, holding 5 oz. of silver per fodder, in the whole 130 oz., afforded, after three successive crystallizations, — \ t t ! 638 SILVER. 440 cwts. of poor lead, holding | oz. of silver per fodder; in aU I5cwts.49 — holding the original quantity, nearly - 84 cwts. oflead for the cupel, holding 29 oz. ... 116 Total J3Q 1 cwt. of loss, principally in the reduction of dross. The expenses of the new method altogether, including 3«. per fodder of natent dues in^eipenlesl-"''' "^""^ '**^^'^' *^^ treatment of argentiferous le«d occasions the follow- FOR ONE FODDER. £ ,. d. ay tne new process - - - . . . . 13 7 By the old process - - . . . . -222 tK^«°'fiI'"" ^^^\^^^ treatment of sUver holding lead is economically possible only when St/w-^^'f.'^''^^ to one tenth of the gross expenses of the process, wVn.ay easily cllcu. tentsTn silve^r?-*" ' ' ^ sufficient for the leiid to have the foUowing coS With the new process, 3 ounces per fodder; or, - - 0*000078 With the old process, 8_4_ ounces per fodder ; or, - - 0000218 To conclude, the refining by crystallization reduces the cost of the partin- of lead and silver, m the proportion of three to one; and allowsof extracting silverfom\ lead which contains only about three oz. per ton. In England, the new method produces at p^sint IZed "tires' rr'''' Vr'f'/ '^ ^^'^^"^^ '^ '"^^ --^^ --»«-« ^^ ^^7^ l ^aTbe V^lfnln h.H iL * ^ '^"^"^'^^ ""^ "^^ ^''""^"y ^-^^'•^^t^^ ^'^"^ the mines in the United Kingdom had been progressively raised to 47,000 tons. Reduced almost to one half of this amount m 1832, by the competition of the mines of la Sierra de Gador, the En^Ush r. h«Tnrl'^ K ^^r V" •""""'" ^" ^^^^' ^" ^«3^' 35,000 tons of lead were oSS, one half of which only having a mean content of eiaht and a half ounces of silver per ton ^tlL"ffit?oVa?e^'''°"' '"' "'"'"'^ '''"'" °" ^' ^"^ P^^"«"^ -etal!' xLTetaUs SUver extracted from 17,500 Ions oflead, holding upon the average ei-ht > and a half ounces per ton, - . . . . - . (140,000 02. SUver extracted from sUver ores, properly so caUed, in Cornwall, " - 36,000 176,000 See Smelting of Lead. • I^}^V' *f production of lead amounted probably to 40,000 tons: upon which the introduction of the new method would have the effect not only of reducin/consideraWr the cost of partmg the 20,000 tons of lead containing 8 oz. of silver, per ton bu of ^? mittiDg the extraction of 4 or 6 oz. of silver, which may be supposerto eist upol^ VZT. '^ \ 1 g'-eater portion of the remaining 20,000 tons. Otterwiae. this mass of the precious metal would have had no value, or have been unproductive rJ.Jr'^''^'^^''i? apparatus of Locke, Blacket and Co., consists of seven crystallizini? pots, and one smaller pot for receiving the desilverized lead. They are aU made of S iron, and arranged m a straight line. The lead in each pot varies in its contents of silver. The first containing 86 cwt lead at about 60 oz. of silver, or ^t. per ton Is divided into 55 cwt. crystals carried to second pot, at 36 o^pirton 18 cwt. do. to be put in first pot again, at 64 oz. per ton and 12 cwt rich lead to be cupelled, at 170 oz. per ton The second pot containing 90 cwt lead, at about 35 oz. silver per ton Is divided mto 60 cwt crystals carried to third pot, at 20 oz. per ton and 80 cwt. lead put into first pot, at 66 oz. per ton oz. oz. • 256 • 96 - 67 - 102 265 . 167 - 60 - 97 w SILVER. The third pot containing 90 cwts. of lead, at about 20 oz. per ton Is divided into 55 cwts. crystals carried to fourth pot, at 10 oz. per ton - and 25 cwts. lead put into second pot, at 36 oz. per ton - The fourth pot containing 80 cwts. lead, at about 10 oz. per ton Is divided mto 55 cwts. crystals, carried to fifth pot, at 5| oz. per ton and 25 cwts. lead put into third pot, at 20 oz. per ton The fifth pot containing 80 cwts. lead, at about 5| oz. silver per ton - Is divided into 55 cwts. crystals, put into sixth pot, at 3 oz. per ton - and 25 cwts. lead, put into fourth pot, at 11 oz. per ton - The sixth pot containing 80 cwts. lead, at about 3 oz. per ton - - . Is divided into 55 cwts. crystals, carried to seventh pot, at 1| oz. per ton - and 25 cwts. lead, put into fifth pot, at 6 oz. per ton - The seventh pot containing 55 cwts. lead, at about 1| oz. per ton - Is divided into 25 cwts. crystals, carried to small pot, at 1| oz. per ton - and 30 cwts. lead, put into sixth pot, at 2| oz. per ton 27 63 15 25 4| 639 90 90 40 40 22 22 12 12 4 The above 25 cwts. of crystals are melted and cast into pigs and sent to the market. in operating upon lead containing about 10 oz. per ton, the fourth pot is filled with It; It It should contain 20 oz., or thereabouts, it is put into the third pot: and so of any other. fig. 1298 represents the arrangement of the iron pots or caldrons, in their order. The desilvermg apparatus represented m;2g.l298is composed of five caldrons of cast iron, each heated by its own fire, besides two smaller pots, similarly heated The caldrons rest by their upper flange and surface upon bricks property fomk and arranged. Theur shape is not hemispherical; their mouth is 40 inches in len^ hm only 26 inches in width Over the door of the fireplace, the moutIS stendfsVeet 4 inches above the ground or bottom of the ash-pit, of which space, 18 inchS^iL™« wtwecn the grate and the brun. The grate is 2 feet long and 8f Lches ^de Tfl ThV?fth~«w*-' ^^%'!^t«»ipt.i<^ form, with a bottom like the smiu end ^L e« ^nf ^ ? v^ •? smaller, but this one serves merely to melt the lead which hMbefn •tnpped of Its silver, in order to be cast into salmons or blocks. ^^ The charge consists of 64 or 65 salmons, each weighing from 120 to 140 lbs Wl,pn they are well melted, the fire is removed from the grate, as well m thp LSi' fii ? posture m this plane. During this operation, intended to establisra un^or^^mnei ture throughout the mass, a second workman heats in the smaUe? pot XiS to No. 1 a large skimmer at the end of a long wooden handle, and next proceeds to^fish out the crystals, taking care to let them drain off for a few seconds aU The lloud leS «nong them, and then turns ont the crystah, slowly into the next ca?dron. No 2^ the second workman meanwhile adds the metal solidifi'ed round the s dS, and stiS all together to equalise the temperature. These two-fold operations occ^pV about fifty ,' i ; 640 SILVER. mmxxtea j by which time, there remains in the caldron about 16 salmons. The workman now lifts out the crystals, as before, with the drainer, and throws them upon the ground in two heaps. His assistant takes them up a little while afterward, and puts them away to make room for fresh crystals, which the first workman continues to throw ^^-"^^ J^ ^•°*'^'^ ^r- T *'" ^''^y ® ^^°°^ '^"^^^^ i° the caldron, a point ascer- tained by gauging the height to the bath. The fire being at this time reioy«i from cauldron No. 2 into the grate of No. I, the 8 salmons of lead enriched with silve^ which remain at the bottom of the caldron, are run out into movable moulds ; and the 8 salmons which were thrown upon the ground are put into it ; the full charce beinc then made up with salmons of the same richness as those previously used While this mass is melting in No. 1 the process just finished in it is repeated in No. 2. About three fourths of the metallic mass is next separated in the state of crystals, which are transferred to No. 3, and also one eighth of crystals thrown on the ground, after pouring the remaining one eighth at the bottom of caldron No. 2 not into moulds, but into No. 1. », ^ uu^ A like process is performed in caldrons 3 and 4; and the poor lead taken out of 4 is transferred to 5 to be melted, and run into salmons, which are submitted afresh to the preceding senes of crystallizations, provided the lead still contains a sufficient proportion The following Table will place the results of the above successive operations in a clear light : — Original lead ---•._ 1. Rich crystals ---«.. 2. Poor ditto ----.. — Rich ditto > proceeding from the treatment of the prece- 3. Poor ditto $ ine No. 2 poor crystals 4. Rich ) proceeding from the treatment of No. 3 poor crvs- — Poor Stals r-j (Lead)poor l as above fitim No. 4 Silver in 1 Ton of Lead. 0-001153 0-003324 0-000933 0-0020802 0-0007021 0-001399 0-0004569 0-0008135 0-0001128 We thus see, that four crystallizations, repeated upon the original lead from the smelting furnace, of the above richness, will afford a lead ten times poorer. With a lead originally containing only 0-0002248 in silver, three crystallizations would suffice to make It ten times poorer. In general, the poorer the lead, within certain limits, the better adapted is it to this process. 1 TK^'fl T- *I? ^""'au ''^J^''^'' ', ^^^^^ *'^^°*^^ ^^'^^' »°d suroxide, by Berzelius 1 The first IS obiamed by adding solution of caustic potassa. or lime-water, to a solutbn of nitrate of silver. The precipitate has a browhish-gray colour, which darkens wheS dried, and contains no combined water. Its specific gravity is Y-143. On exoosure to the sun, It gives out a certain (Quantity of oxygen, and becomes a black powder This oxide 18 an energetic base ; being slightly soluble in pure water, reacting fike the a kalis, upon reddened litmus I>aper and displacing, from their combinations with the alkalis, a portion of the acids, with which it forms insoluble compounds. It is iosolub e m the caustic yes of potassa or soda. By combination with caustic ammonia, it forms fulminating silver. This formidable substance may be prepared by DreciDitatin^ thp nitrate of silver with lime-water, washing the oxide^upon^a £ter, anLpreX^ i^^upon gray paper, to make it nearly dry Upon the oxide, still moist, water of ammonia isT be poured, and^allowed to remain for several hours. The powder, which becomes black, w to be freed from the supernatant liquor by decantation, divided into small portion while moist, and set aside to dry upon bits of porous paper. Fulminating silver may be made more expeditiously by dissolving the nitrate in water of pure ammonia, and I)recipitating by the addition of caustic potassa lye in slight excess. If fulminating silver be pressed with a hard body m its moist state, it detonates with unparalleled violence; nay, When touched even w th a feather, in its dry state, it frequentl^exp odes As many persons have been seriously wounded, and some have been killed, by these explosions, the utmost precaution should be taken, especially by young chemiste, in its preparation. This violent phenomenon is caused by the sudden production of water and mtrog^, at the instant when the metallic oxidfe is reduced. ^The quiescent and r'^tl "iVf-^" i!^' '^•°' *i^^ ''' °'^^^7 ^a^a^ced in this curious compound/that the slightest disturbance is sufficient to incite the hydrogen of the ammonia to snatch the oxygen from the silver. The oxide of silver dissolves in glassy fluxes, and renders them yellow. It consists, according to Berzehus, of 6311 parts of silver, and 9-89 of oxygen. 2. The suroxide of silver is obtained by passing a voltaic current through a weak solu- tion of the nitrate- It being deposited, of course, at the positive or oxygenating pole It 18 said to ciystaUize m needles of a metalUc lustre, interlacing one another, whicharo SILVER. 641 one-third of an inch long. When thrown into muriatic acid, it causes the disengage- ment of chlorine, and the formation of chloride of silver ; into water of amsionia, it occasions such a rapid production of nitrogen gas, with a Iiissing sound, as to convert the whole liquid into froth. If a little of it, mixed with phosphorus, be struck with a hammer, a loud detonation ensues. With heat it depreciates, and becomes metallic silver. Sulphuret of silver, which exists native, may be readily prepared by fusing the constituents toorether; and it forms spontaneously upon the surface of silver exposed to the air of inhabited places, or plunged into eggs, especially rotten ones. The tarnish may be easily removed, by rubbing the metal with a solution of catneleon mineral^ jM-epared by calcining peroxide of manganese with nitre. Sulphuret of silver is a powerful sulpho-base ; since though it be heated to redness in close vessels, it retains the volatile sulphides, whose combinations with the alkalis are decomposed at that temperature. It consists of 87-04 of silver, and 1296 of oxygen. A small quantity of tin, alloyed with silver, destroys its ductility. The best method of separating these two metals, is to laminate the alloy into thin plates, and distil them along with corrosive sublimate. The bichloride of tin comes over in vapours, and condenses in the receiver. Silver and lead, when combined, are separated by heat alone in the process of cupellation, as described in the article Assay, and in the reduction of silver ores. See suprd. An alloy, containing from one-twelfth to one-tenth of copper, constitutes the silver coin of most nations ; being a harder and more durable metal under friction than pure silver. When this alloy is boiled with a solution of cream of tartar and sea-salt, or scrubbed with water of ammonia, the superficial particles of copper are removed, and a surface of fine silver is left Oliloiide of silver is obtained by adding muriatic acid, or any soluble muriate, to a solution of nitrate of silver. A curdy precipitate falls, quite insoluble in water, whidi being dried and heated to dull redness, fuses into a semi-transparent gray mass, called, from its appearance, horn-silver. Chloride of silver dissolves readily in water of ammonia, and crystallizes in proportion as the ammonia evaporates. It is not decom- posed by a red heat, even when mixed with calcined charcoal ; but when hydrogen or steam is passed over the fused chloride, muriatic acid exhales, and silver remains. When fused along with potassa (or its carbonate), the silver is also revived ; while oxygen (or also carbonic acid) gas is liberated, and chloride of potassium is formed. Alkaline solutions do not decompose chloride of silver. When this compound is exposed to light, it suffers a partial decomposition, muriatic acid being disengaged. See Assay by the humid method. The best way of reducing the chloride of silver, says Mohr, is to mix it with one-third of its weight of colophony (black rosin), and to heat the mixture moderately in a crucible till the flame ceases to have a greenish-blue colour ; then suddenly to increase the fire, so as to melt the metal into an ingot The subchloride may be directly formed, by pouring a solution of deuto-chloride of copper or iron upon silver leaf. The metal is speedily changed into black spangles, which, being immediately washed and dried, constitute subchloride of silver. If the contact of the solutions be prolonged, chloride would be formed. The bromide, cyanide, fluoride, and iodide of silver, have not been applied to any use in the arts. Sulphate of silver may be prepared by boiUag sulphuric acid upon the metal. See Refinikg of Gold and Silver. It dissolves in 88 parts of boiling water, but the greater part of the salt crystallizes in small needles as the solution cools. It consists of 118 parts of oxide, combined with 40 parts of dry acid. Solutions of the hyposulphite of potassa, soda, and lime, whidi are bitter salts, dissolve chloride of silver, a tasteless substance, into liquids possessed of the most palling sweetness, but not at all of any metallic taste. The iodide of silver is remarkable, like some other metallic compounds, for changing its colour alternately with heat and cold. If a sheet of white paper be washed over with a solution of nitrate of silver, and afterwards with a somewhat dilute solution of hydrio- date of potash, it will immediately assume the pale yellow tint of the cold silver iodide. On placing the paper before the fire, it will change colour from a pale primrose to a gaudy brilliant yellow, like the sun-flower ; and on being cooled, it will again resume the primrose hue. These alternations may be repeated indefinitely, like those with the salts of cobalt, provided too great a heat be not applied. The pressure of a finger upon the hot yellow paper makes a white spot, by cooling it quickly. Fulminate of silver is prepared in the same way as Fulminate of Mercwry, which see. On 'the 10th of February, 1798, the Lords of the Privy Council appointed the Hoc Charles Cavendish, F. R. S., and Charles Hatchett, Esq., F. R. S., to make investigation* upon the wear of gold coin by friction. Their admirable experiments were begun in the latter end of 1798, and completed in April, 1801, having been instituted and coa- 41 h I! iM' 642 SILVER. ducted with every mechanical aid aa r]ev;««>/l kx, *i.^ phers.and provided, at no stall ex^nse^ the ^^^^^^^^^ ^^'^"^ important conclusions of their officialVeport :—* S^^^ernment. The following are the " Gold made standard bv a mixture of pnnnl rka-*- ^t m as gold alloyed only with silveT^Ser is t so^nat f "•!"'' *"^ "°PP^'' '' °«' «> «oft and stamped with great facilitv- «n!i ,VnJ ^ ^"'PP'^''- ^* "^^y also be rolled le,«by friction than |;i5'afq;!:7by'^u;:rtrp*;:^a'ire'"'^""'- " ''^^"' '» "^'' Of ete.fe^r„ rtU*";:^^^ f- the s„rfa« be preferred for coin." ^^ "^^^"^ *°^ copper is rather to any scientific reason or resS anLrendv fo? rhJ ^°*""^l^ '^' ** °°"-»^^' ^^^hout in our mint a good job^n sw^aU^^^^^^^ ^^ ^'^'"^ ^ ^^'"tain official it. in the newloina^e. With Top^^^^^lf o ,11^^^^^ ^^ -PJ-ng ounce of our excellent gold cdn and charging tKunirvS/f!' ''"\^^ '?'*' besides the very considerable exDen«;e in nrnviHmiV ^ ^ ^""^ '^^ extraction. The pretence s-^t up for ISs "rt^rd n^^^^ ^P^-^ *'-, -l-er coin might peradventure be exported in ord^r tn k1 ^ i ^ ?*".' '^^'' ^^^^ <>"' which could have been most readilv avert^l L ?.o^ de-si vered abroad, a danger sovereign as was equivalenTtoX s^lvVr ntldu^ed^^^^^^^^^ n^^.""'' ^"^ ''' ""'^^ value m precious metal. When the film of fina S u- u P^^^serving its intrinsic pieces has^ been rubbed offfrom tie prLfnent n!r f 7h '^ '^'f ' '^^ "^ ^"^ P''^^^"' ferent and deeper colour tlian thr/at Tr! ^ ' ^^^^o^^st appear of a very dif- therefore, is suLently appa'en '"^ ^^ '^?. ^^ " T^^« '^^^^^ ailver only, cannot be hab?e^ to thisUmUh '^a^H i'^^ '^ ^""^^^ with .be much jess liable to it, thaV wu"; alol"^ ^rdrd thl -IV ^^' ^' ""«^ m a late Committee of the House of Common, on ?L m- ^* k,- J^^e pohtical economista lie economy and expediency ? Commons on the Mint blink this question of pub- Gold, as imported from America Asia anA Af-Uo ^ x • right proportion of silver for mScMhe £t t^^'.T^ ? n" ''^?'"^-" "^"^^ ^^ standard, of 22 parts of gold 1 orsilver and In? '/ ^ere it alloved to our national dish and Hatchett, then by aim pi v adding Z ifi.' P^'' ^ ^^^""^^ ^^ ^^'''^ ^aven- metals, by the rulk of allSn the very consfd^^^^^^^^^^^ ^"""*'*'"^ "^ ?^\^' *^« ^^ th^^^ nation, a/d sulphureous n^is^nce to the VoZ H^m^^^^^^^ ^ ^^^^^ *« *»^« silvering and cuprifying sovereigns at the Rojal Mir ' ^°^'^'^ '^'"'"'""^ ^" **«- Mexico amounts only £, from 8 to O^fof a ' ; f, ^^f^.T' T"'"L''^"^^^ ^" m 100 lbs.; the true'average being, perhaps, no? Tore than 2^ U L'ZV''-^ 'T^' silvW cCTs^^^ttd'^td'r tt ftlfe 'oVchrf ^ ''^' {' -^«- ^/ -^- ^e thus ascertained; the eh" IfteV h^W^g tet' wd^^ f "'^ -"^^ IS to be put into a stoppered wide-necked bottle a 01^1 v of rpfinl^ ^''''^ ^^PP^'' candy, is then added, equal in weight to the -illov * ^"?".^'*y .^^ ,^6^^?^ ^"gar, or sugar- of a solution, composed^ 60 JaSs of ^o^ L/^ 1 mixed with an equal volSme distilled water, which will vYdS^^lution^ o1^ n^tf h^ f J^o^^^' *"^ ^^^ ^''^'^^^^ «f after closing the bottle the mixture i^ to ^^ ^^u^ ,^.^T^' ""' t^^ereabouts : it occasionSly, to favour thrreacUon After^thU ' ^"f l^'° '^' ^^ ^^ hours, shaking several times, until the last wa^h n^^^^^ ^l Z"'"^ ^1 "J"P'-'^' '^ '« *« ^ ^^^^ed which should be preceded b;tn^'iSurpaT ^l" ct ot^^^^^^^^^ l}^^^ or show any change whatever Thl, dnnp tho /.«JU * Y"'<^^ ought not to become blue, to a porce/ain capsule, byThe he?; of ri it 'rt^nr/ waVer^t^^^ t"^ '\T''T^ deposit the excess of licuid is poured off, and tfetlveT d^Ted ^^^^^ 's""^ ""'^'^ *^ By these means we o\tam that to which I have given the name of^y ,Uver. Thi. ♦ It Is inserted in the PhUoeophical TramacUom for 1808L SILVER. 643 silver consists of some bright spangles, which become more brilliant on friction. It does not contain any impurities, with the exception of a small quantity of oxide, and a few atoms of chloride of silver. This latter produces a slight turbidity in the liquor, when dissolved in perfectly pure nitric acid, and diluted with distilled water. Thia turbidity does not, however, prevent the formation of pure nitrate of silver: as the Chloride being only m suspension in the liquid, it is sufficient to filter it on a small portion of well washed asbestos, in order to obtain an unobjectionable liquor. The nitrate of silver will not contain any trace of other metals, as none are used in the reduction of the chloride of silver, and by the reduction of this salt, the silver is com- pletely separated from the iron and copper which the solution might contain. Thus the nitric acid of commerce may be employed, without inconvenience, for dissolving the The grey «7»ct- almost always contains a small quantity of oxide ; this is easily verified by the addition of ammonia, which, after digestion on the metal and filtration, produces a slight turbidity on adding mtric acid, which is caused by the separation of the dissolved chloride of silver; the turbidity is then increased by the addition of a small quantity of chloride of sodium to the nitrate of ammonia previously formed ; thus, then, is the oxide of Sliver dissolved m the liquor m the state of ammoniacal nitrate, which is precipiuted m the form of insoluble chloride. *^ Oxide of silver not being an impurity in the uses to which pure silver is applied in laboratories, we may consider the grey silver obtained in the manner above descnbed as more pure, and with less loss, than any of those prepared up to the present time, by the reduction of chloride of silver ; and without the necessity of melting, a troublesome operation ana one of much inconvenience in a laboratory. «i.f '*°°"i T^.r''^'' ^°"*' Spanish franc), the weight of which was 5759 grammes, I ^l^'^^t t • /'S"?''' ""^J""'^ *'''^''"' ^"^ supposing that the standard wal at 90 ^r cent, which IS doubtful as the money of Seville has often an infenor standard, I obtained ^Jj^'fT' ""^ ??^ '"'''-^T contained in the alloy; but the remainder is not lost, as the waters of the washing acidulated by nitric acid are poured into the vessel on the precipi- tates of silver, and form a fresh chloride. ^ ^ *dt fT'''"n \^'^ mixture for the purpose of obtaining the grey silver, it will be observed irnln i'*"^'^^^^^' ^'"*=^; ^« ^^6 first instauce is white, changes to a dirty reddish- I^r?, ^Z'\ ^,f """^yt \^ \'o^\-}^^ted grey ; and, finally, to a blackish-brown. It ^?vtM? 11 K "^i"^' !""' *>","^ '^^^^ ""^ *'«"'■' ^' *^« e"d «^ ^hich time, the whole of tm^l ^r ^- ^T^- ^"tirely covered with a thin layer of brilliant silver, forming a ^mplete cyhndrical mirror. This layer wiU remain as long as the liquid is not much ^J^^ Z^u^ ''^''•'''- «^^hich I treat in the memoir from whence this note is extracted, is obtained by precpitatir.g oxide of silver, and oxide of copper, by potash, then reducing oxide of silver by sugar, taking certain precautions ; but, from the alloy only 46 per cent of SI yens obtained. In the state of dead silver, it is as white as pumice stone ; and, by simple friction with a g ass rod it assumes considerable briUiancy. The white silver is free from oxide or chloride— it is chemically picre. ^ Production of silver in Spain, by Frederick Burr, Esq., Mining Engineer. In the earliest ages of authentic history, Spain was one of the countries most cdebrated for the pr^ ^^^'ZlJin r ^ " '^^'.f 5^i""y *J" ^"**«^- ^' PhcEnicians and Cartha^ n ansC said indeed to have freighted their ships with these metals, and even tohfveformid their anchors of them. On the subject of ancient mining ii Spain T Spanllh wrher fio onn^K P 7' X?P^'^" °^**^?"^ ^"""^"3^ f""""* «*!"«». the Asturias and Lusi S ♦h;?p «./p'- ""^ f ^1' f we are informed by Pliny, who extols the quanUty of gold S ISS^^i!rHP^'f 1^'^^ '" ^"^^ ^''""^'- '^'^^ «"^«^ «f Spain was found in such quantity that, according to the same author, Hannibal in a mine worked by him nearCartTena extracted daily a quantity which exceeded 80.000 reals (300/.) of ™ur money Cato 4SoTi:L of'lV a'll'TwZh?'?: '^- °' '""r ^" ^^^« *"^ 120.00oTn money'^-besidt 400 Itw. ot gold all of which he had accumulated in Spain. Helvetiu<» who was onlv governor of Andalusia, delivered 3Y,000 lbs. of silver in ^in, and 40.00^ C of Tver In rpmorW?«fTif '"" • '^''''^' of the production of the precious metals in Spain. I would diSo er L of s^e?^ t"^' their coiTectne^ss. both from the resuTt of mo ^"^"t Sierra Almagrcra, in the province ofAWrU i r 1839 the celebrated mines of the recent and minor disLe iea I m^^ta 'e tha^w?tWn7l, P'"^."?'™- P'^'ng over more of Mr. Pattinson'a desilverizinR processhas hLrl. ^', f*'' /«"« "« introduction prl^e^lrof^^|[5S£H=^^^^^^^ of the Sierra /imagrmTnT MnrSt Z ^nf thi yt^ C""l''8'i;*'"'i"'T' '''"™'" Srre^LfLsr^Tootd^-f^^^^^^^^^ theSierra A.ma/era-2t:^ S^ o^^eSt^ Hrrnt^^K^r^ Tear& Silver, in marca* 1841 1842 1848 1844 1846 1846 1841 Total in the seven years. 10,178 56,676 143,331 159,285 144,829 185,141 103,985 752,926 marc5. have declined considerTbW 3Cd fcount of th^? ft. "'"' ""'"•''' »"<' Foduclion level, and partly from harinVml^ wi.^ wL° ■ ¥ 'f^" ^"""'"g Poorer below a certain have neces Vbeen^ns^n^r' rs'jm'4 ^nf C-hrvIr'^at len'^ T ^*"^^'!? mines in the year 1850 wm 40 m? r^tt.! ^r ^:?*'^<^*^«n- The produce of the Almagrera about the saL ; for aUrugh 1L rk^mfnes JiL"^^ ^'^^^^ ^'"^^ *^^" '^^^-^^ other discoveries have been madp in tL^" ai '^^*'^'' ^^^^ continued to decline, ward, which will ha;;Sribufed ?o W u^^^^^^^^^ ^V^"^*^" ^"^^ ^^ ^^^ ^e^t-' Of the produce of the m^«s nf w;!? i^ ■ /T^"* P'-^'l^ction of silver. although Lre uniform thrtUoMhfLTerr^^^^^ ""\T° 1°^ «^*^°^^"*' ^* inferior to it ^ ^'®'^'^* Almagrera, it has been considerably gm^eVSl^jItea\n'''^^e'3';?es™"C^^^^^ ""^ *™™- «-'/ traordinary size, being in places 6 or R to, i ^ '^'^^ "/ *^® '^^^''^^ '"'"es is of ex, Cbiefl, argWo. WK^idUr^re^rur^^b-uV^^^f*.^^^^^^^ • Tb« oonees havo bean hare omitted. SILVERING OF GLASS. 6^ rate state. The lodes of Hiendelencina run nearly east and west ; they seldom exceed 3 feet iu width, and are properly silver lodes, as they produce the ores of silver, ss chlorides and sulphurets, but unmixed with any ores of lead. The Silver of the Sierra Almagrera has been almost entirely exported to Marseilles— that of Hiendelencina is •ent to Madrid. The silver coinage of Spain has not been therefore by any means so considerable as might be inferred from her large production of that metal. It is stated, however, that in the year 1850, the total quantity of silver coined in Spain, in the three mints of Madrid, Barcelona, and Seville, amounted to the value of 27,780,319 reals, or, in round numbers, about 280,000/. sterling ; the silver proceeded chiefly from the mines of Hiendelencina and Sierra Almagrera, exclusive of course of the bar silver which was exported. Mr. R H. "Wilson, Consul for Peru, estimates the produce of the Peruvian mines at about 5,210,000 dollars a-year; about 3,500,000 dollars of this amount are exported on English, French, German, and Spanish account The whole annual production of Europe and Asiatic Russia, has been rated by Humboldt at 292,000 marcs ; by other authorities, at 810,000 ; while at the beginning of the present century, that of the Spanish colonies in America was 3,849,160 marcs, or nearly twelve times as much. The sum total is 3,704,160 marcs, of 3609 grains troy each ; which is nearly 1,900,000 lbs. avoirdupois ; that is, little less than 9000 tons. The whole of the mines of the Zmeinsgorsk Circle have yielded an aggregate of 183,884,116 poods of ores, from which have been extracted 69,708 poods of silver, con- taining a quantity of gold estimated at 1,900 poods. We are indebted for the following valuable tables to M. Michel Chevalier's Remark* on the Production of the Precious Metals, translated by D. Forbes Campbell, Esq. Comparative Table, showing the annual Produce (approximate Calculation) in value of fine Gold and Silver, for 1846 and 1850, the former being Two Years before, the latter Two Years after the Discovery of the Gold Mines in California. California - - United States Mexico - - - New Grenada Peru - - - . Bolivia - - - Chili- - - . BfHzil - - - Total of North and South America - 1846. Gold. 237,336 249,7.W 252,407 96,24 1 60,337 145,585 259,871 Silver. 1,864 3,457,020 42,929 1,000,583 460,191 297,029 2,003 Total. 1,301,560 Russia - - - - Norway - - - - North Germany - Siixony - - - . Austria - - - . Piedmont - - - Spain - - - - . United Kingdom ' Africa . - - . . Borneo - - • - . Ava .----, Malacca - - . , Sumatra • ■ . . Annan or Tonquin Various countries* ■ Total of Europe, AOica, and Asia - Total of North and South America - 3,414,427 357 5,261,619 282,750 17,841 3,498 203.900 305,900 100,000 72,240 63,719 30,585 50,975 4,545,192 1,301,560 Total 5,846,752 167,831 32.346 138,022 198,200 282,654 7,444 227,499 109,989 1,056 1,584 517 374 330 53,460 33,000 239,230 3,706,773 295,336 1,096,824 520,548 442,614 261,874 1830. Gold. 6,563,179 1,254,306 5,261,619 3,582,258 32,346 138.379 198,200 565,404 25.285 229,997 109,989 204,956 307,484 100,517 72,614 64,049 84,045 83,975 6,515,925 5,799,498 6,563,179 £ 12,000,000 115,430 382,901 252,407 96,241 60,357 145,5p5 289,068 Silver. 13,341,989 4,175,860 357 288.708 17,841 2,498 203,900 305,850 100,000 72,240 63,719 30,585 50,975 5,312,533 13,341,989 12,362,677 18,654,522 £ 62,088 11,444 5,383,333 42,929 1,000,583 460.191 297,029 2,227 Totel. 7,259.824 171,817 35,607 138.022 198,200 286,971 7,444 440,210 160.000 1,056 1,584 517 374 330 53,460 33,000 1,528,592 7,259,824 £ 12,062,088 126,874 5,766,234 295,336 1,096.824 520,548 442,614 291,295 20,601,813 4,347,477 35,607 138,379 198,200 575,679 25.285 442,708 160,000 204,956 307.484 100,517 72,614 64,049 64,045 83,975 6,840,975 20,601.813 8,788,416 27,442,788 * Exclusive of China and Japan, which produce large quanUties of gold and silver, the amount of which 18 quite unknown to Europeans. * «"•»", «jc ouiuunk ui n ???^■i;^.hi^i^n!f'^r'"/ f '?v'^.K ''^i'^S'^' ."*'*»° Humboldt's estimate (Sssai PolUiqus, tome ii , SAih inH ^Sl^iTiJ^r^^''^*' ?%\^^^^ America was 17,591 kilogrammes - 46,331 lbs. troy of ra V^J ^h ''''oerammes-. 2,131 770 lbs. of silver ; value of both metals in dollars, 43,500.00ol to V^i^Lh ^,K® produce of Europe and Northern Asia at the same time was 4,916 lbs. of gold, 250,593i • Korth^ Arii'io 152 OaS ' °^ ^^ ^'^^°"' ""^^^ raised in Americ^ K^rop;/^;^ 646 M ■ .' ■H SILVER. The following table is similar to the ahovA nrl*\> ♦u- ^ i- eubstituted for values. ®' ^'^^ *^® exception that quantuea art •California United States •---. ^flnL*^oki!° ^^' ^^ *^® ^"'"^ washing 98o"lbs. *VoW^' ''^ "P®*^"**" °^ parting, 3,920 lbs. fine ^lT«n r"^ ^■~*° *^^' '^y ^''e English Colom-i In ll^ K** Company. 343 lbs. fine gold. J^'.7'*/.K^ « ^"^'i^'^ Marmato Gold Com- Pe?r - - - . ® *. **: *"** ^^ ''^ ^°« »"^er. J Bolivia ".""""'" ^abou?n^; fl^ '^^ .?"«''i^ ^"«Po" Compa'ny; • Rr^rn 1^ iflr^^l^'"*' '^^ T.oodlbs. fine silver rTv r"Ti"p^^^' ^^ ^,^« En?ri9h St. John d'eH 5» L? J^ Company, 1425 lbs. gold, containing •«o per cent, silver. * 1850, by ditto, 2,517 lbs. gold, containing 20 per cent, silver. *^ 1846, by the English Imperial Brazilian Gold S^r^cffiiJ^eV" ^°''' ^^''^"'°« '^^^^ " 1850, by ditto, 379 lbs. gold, containing about 14 per cent, silver. 1846, by the English National Brazilian Gold Company, 89 lbs. gold, containing about 14 per Ociii* Silver* 1850, by ditto, 120 lbs. gold, containing about 14 per cent, silver. I'otal of North and South America Russia:— 1846, by private mines in the J Ural 8,125 lbs. Public ditto- - - 5,672 lbs. Private. Siberia - 57,235 lbs. Public ditto- - - 2,555 lbs., 73,587 lbs. 9 per cent } alloy. J Norway (Kongsberg silver mines) North Germany (Hartz Mountains) - - - . Saxony ' Austria, in 1846, by private mines, about 4,100 lbs. pure gold, and 34,400 lbs. pure silver Bv fi!H®^S^",K™'"*'^' "**«"* ^'*^^ 'bs. pure gold, and 51,200 lbs. pure silver - - - - . .* ' Piedmont ---------..,.* Spain -------....I"'*" United Kingdom -----.1111" •Africa ------.-. .11*3" * Borneo ------.••111"'" *Ava --- -Ill*'* * Malacca- -------.III''" •Sumatra -------IIIII^' Annan or Tonqnin --~...ll''' Various countries - ---.-..'"" TotalofEurope, Africa, and Asia- - - Total of North and South America - - - Grand Total 184& Pur* Gold. Lbf. Troy. 4,625 4,900 4,954 1,888 1,184 2,856 5,096 25,503 66,985 5,549 350 49 4,000 6,000 1,961 1,420 1,250 600 1.000 89,171 25,503 Put* tr.lrer. Lbt. Troy. 565 1,047,582 13,009 303.207 139.452 90,009 1850. Pure Gold. Lb«. Trey. 235.409 2,263 7,509 4,954 1,888 1,184 2,856 Pur« Silver. Lb«. Troy. 18.814 3,165 1,631,313 13,009 303,207 139,452 90,009 607 5,668 675 1,594.431 261,731 50,858 9.802 41,825 60,606 85,653 2,2.56 68,953 33,330 320 480 157 113 100 16.200 10,000 2,199,644 81,919 384.653 1,594,431 5,663 350 49 4,000 6,000 1,961 1,420 1,250 600 1,000 52,053 10,790 41.825 60,606 86.961 2.256 133.397 48,484 320 480 157 113 100 16,200 10,000 Enrope, Africa, and Asia 247 lbs. British standard gold - 18,654,322^. ^ ^' ' ''*'• ' ^^^ Produce, 365,950 lbs. - 399, • Those countries marked thus C*i havn *,« o«i..« having existed in the native gold.'^to We JJI^a^e aSoSntTs" "I I^Ji'' ' '"^^ «" average amount of 8 per cent. Iver stated is estimated SILVER. 64*) Total Production of the Silver and Gold Mines of America prior to the Discovery of th« Gold Mines of California. Ootmtriei. United States - - - Mexico ------ New Grenada - - - Peru ; Bolivia ) - - - - - Brazil -...-- Chili Totals Silver. Weight in Kilogramme*. 61,985,522 259,774 58,765,244 1,040,184 122,050,724 V»lne in Miliiona of FrHDcs. V3,774 58 13,059 251 27,122 Gold. Weight in Kilogrammes. 22,125 389,269 566,748 340,393 1,342.300 250,142 2,940,977 Value in Milliotu of Fraoc*. 76 1,341 1,952 1,172 4,623 862 10,026 ToUl for each Country in Miliiooa of Francs. 76 15.115 2,010 14.331 4.623 1,093 37,148 ' (I Quantities of Gold and Silver supplied to the European Markets by the undermentioned Countries during three Centuriies ending in 1848. Countries. Silver. Gold. Weight in Kilogramme!. Value in Millions of Francs. Weight in Kilogrammes. Valne in Miliiona of Franca. Europe, exclusive of Russia Russia -.- Africa, and the Islands of the Malay Archi- pelago, Sec. --.-----.- 9.000.000 1,485,000 2,000 300 445,1.50 319.330 725,750 1,500 1.100 2,500 Totals 10,485,000 2,330 1,490,230 5,100 Gold and Silver produced in Forty Years, from 1790 to 1830. Mexico, ChUe, Buenos Ayres, Russia, Gold. £6,436,453 2,768,488 4,024,895 3,703,743 Sihrer. ;£ 139,8 18,032 1,822,924 27,182,673 1,502,981 Returns of the Dollars coined at the different Mints in Mexico. Mexico Guanajuato Zacatecas Guadalaxara - Durans^o San Luis Ilalpan Total 1829. 1830. 1831. 1834. 1,280,000 2,406,000 4,505,000 596,000 659,000 1,613,000 728,000 1,090,000 2,560,000 5,190,000 592,000 453,000 1,320,000 90,000 1,386,000 2,603,000 4,965,000 590,000 358,000 1,497,000 323,000 952,000 2,703,000 5,527,000 715,000 1,215,000 928,000 11,787,000 11,295,000 1 1,722,000 12,040,000 The English Mint silver contains 222 pennyweights of fine silver, and 18 of copper, m the troy pound of 240 pennyweights : or 92-5 in 100 parts. 1 pound troy = 6760 grains, •ontains 65-8 shillings, each weighing 87-55 grains. The French silver coin contains H$ SILVERING OF GLASS. ^M&l^^f ^^a^^l^^Srr^V^f ^-^- ^-y- ^e Prussian 343-7 grans troy, and contains 257-9 ^J^^Z'tJ 'T'' ^^"^« ^ '^^^^ ^-gh» ^ h^ "^ r"^^' '^^^ ^"«t"«" *^oin Sains ^"ofj' ^'"^ '^^ P^"" ^^"^- ^^ silver. i?ri?r?2^^rti per cent. "''""' ^*8 of alloy, according to Wasserburg SILVER LEAF is made in precisely the «.m. """s/r vrmv'/^^^'- ^^^ ^^«^^'- '^ "^ *^''^ ''«-^' *« ^»''<=h article 1 "■'"•.f-^'-by fheFr„ci;"aS "*'"' '"" """■'"»« "- -*« of .he copper, rteel, of various forms. The workman hi- v' ^^^T ^" "' ««'-<'ace bv burnisher, nf any part darken i„ the hea J^lJ^rbe^S^^^^ ^'^ ^^^^ do«ble"^'''|i^,^S The silverer always works two piece! «nn^« ^ »>yihe scratch-brush. ^'^ bomishing the other. After apT^yin'two sZ/i '" ^^l ^^ "^^^ ^^^' ^he one while the same degree as at first, and he tien fixes on withTh'^k^" '"."^^ ^'^' "P the pieTe to nas applied, one over another, 30 40 50 nr fin i ' ' " * leaves at a time till h. of the silverins. He then burnfahes do^n J?i. t"""?' '""'''"''« '» the dJZ'sMikt ''sX'^'"L'''?/""'^°™'''«^»'p«""^ ^ P«s.areand address, fVhthiJ ShftlnT «J "-is powder is toT mLS w ,h 3 plrS'of ^U' "''! "«"«" «'"l driei whiting, and one and a half of sea salt Aft.r m. ■ ?v ^"^ Peariash, one of washeH net.lrr°" ?""'■""■' 3 Po^nrolsuUT^ JfTn? °^.""""^''^« 'Sa'te, 3 1 he buttons being cleaned, are smeared over wirh tl,», • ' '""' *"e'. '"to a paste. T^^r button t.us acquires a silvery ^ " w£l^ t^^^^ ^^^^ ..;r;;h':n1h7X^r^S^^^trnrr ^' ^^-^'^-^^ »-^ - «Pmt .amish to th^ SILVER^G OF GL \SS A P'^^f «"»•«. *^ ^^'^n'sh, to the But. mirrors, is deposited on glass by Vhe'' fo lofvil '' l''^'"' "^'J ^I *'" ""^^^am as on ,-.ommon n»Tounded with a raise^d bord^er of g Ws^ i^^;?rf ^. ^^^ The plated ng u.trat« of sdver, with which a little alXl 'vaTe/^f f '" -"^'^'^l ^^''^ * ^"'"^^on of doves, have been mixed. The silver is precin t [ted h T"'*' '^^ -•'"^ ^'^ «^ ^''^'» a«4 oik m a metallic state. This method wi^et s^^^^^^^ 'T*'"" 1 '^'' ^^^^hol and Be^ve 10 sUver sraaU irregular and polygooal SINGEING OF WEBS. ea TOTfaces of glass very conveniently ; but the cost of the precious metal, Ac. will preclude Its application to large mirrors. Mr. Dmy ton has patented a plan of making looking glasses and omameutal mirrors by «oatiug gl^s with silver mstead of mercury. He makes a mixture of nitrate of silvw (1 oz.), with half an ounce of water of ammonia and 2 oz. of water, which after atanding for 24 houi^ IS filtered ; (the deposit upon the filter, which is silver, being preserved^ *nd an addition is made thereto of 3 oz. of spirit, (by preference of spirit of wine), at 60 above proof, or wood-spirit ; from 20 to 30 drops of oil of cassia are then added, and after remain.ng for about 6 hours longer, the solution is ready for use. The glas.«. to be silvered with this mixture must have a clean and polished surface; it is to be placed in a borizontal position, and a wall of putty or other suitable material formed round it- so that the solution may cover the surface of the glass, to the depth of from an ei<'hth to a quarter of an inch. After the solution has been poured on the glass, from 6 to°12 droos of a mixture of oil of cloves and spirit of wine, (in the proportion of one part by measure of oil of cloves to three of spirit of wine), are dropped into it at diflFerent places, or the diluted oil of cloves may be nuxed with the solution before it is poured on the gl^s • the more oil of cloves is used, the more rapid will be the decomposition of the silver but it Is preferable to effect it in 2 hours at soonest. When that has taken place, the si>lution IS poured off, and as soon as the silver on the glass is quite dry, it is varnished with a composition formed by melting together equal parts of bee's wax and tallow The solu- tion after being poured off is allowed to stand for 3 or 4 days in a close vessel - as it still contanis silver it may again be employed after filtration, and the addition of k sufficient supply of fresh ingredients to replace those which have been used. The patentee states that he has found that about 18 grains of nitrate of silver are needed foT each «;quare foot of glass ; but the quantity of spirit varies, from evaporation, with the temperature ot the air and the duration of the process. If the glass be placed in an inclined or even .in a vertical position, and the surface covered over, leaving a narrow space for the solution between the surface of the glass and the cover which fits close, then by using spirit without water in the mixture, the object will be accomplished. The colour of the sQvcr may be varied by adding a little oil of thyme or carui. j & ^ Oil of cassia varies much in quality as found in different shops; and if when mixed with the solution, it becomes flaky, the solution must be filtered before being applied SILVERSMITH'S STRIPPING LIQUID, consists of 8 parts of sulphuric acid and 1 part of nitre. r r SIMILOR, is a golden-coloured yariety of brass. SINGEING OF WEBS. The old furnace for singeing cotton goods is represented to longitudinal section,/^. 1299., and in a transverse one in ^. 1300. a is the fire- door , b, the grate ; c, the ashpit ; d, a flue, 6 inches broad, and 2^ high, over which a hoi- low semi-cylindrical mass of cast iron e, is laid, one inch thick at the sides and 2^ thick at the top curvature. The flame passes along the fire flue d, into a side opening /; in the chimney. The goods are swept swiftly over this ignited piece of iron, with con- siderable friction, by means of a wooden roller, and a swing frame for raising them at anv moment out of contact. ° ^ In some shops, semi-cylinders of copper, three quarters of an inch thick, have been sub- stituted for those of iron, m singeing goods prior to bleaching them. The former last three months and do 1500 pieces with one ton of coal ; while the latter, which are an mch and a half thick, wear out in a week, and do no more than from 500 to 600 pieces with the same weight of fuel. '^ In the early part of the year 1818, Mr. Samuel Hall enrolled the specification of a patent for removing the downy fibres of the cotton thread from the interstices of bobU- net lace, or muilins, which he effected by singeing the lace with the flame of a gaa- 960 SINGEING OP WEBS. feabo':': pr:'a;^:^:LS^^^^^ f^^J^, ^V-lms. L, for an improvement through the interstice; of thri^^^as itTL« ♦u^ J'*" ^ ^'"^^ ^^^ A^^e of the gas in a.tSbe placed immediately a^VeX^rr^SL^^^^ ^'^''''' «^ ^ ^P^*^ an air-pump or exhauster. gas-jete, which tube communicates with -%. 1301. shows the construction of the aDDaratna Anmr.i«# opera.. ; „. a, . a ga^pipe. .applied by LS^^Slt ,"?l"T/;ilt'^' loOl r a Tnr fa fcfrf a passes; and when it is ignited the tobbine. ff-T "It' """"S'' "'''<=''■ "' J'*'. the «S . emended. da.wnfapid,>„^e^tl^^^^^^^^ cat!^ Hotd^-^TI^^tif^-eTeV^iol^^^^^^^^^ '? '»« ^om-e. speeifi- ^t1'bjrj'„^r--'-^iri^^^^^^ exhausting apparatua communicates with the pipe e, e, e, which leads to the .nJ?J^t;en^^^ filled with water, beam fe; each of the boxes is furnished wilh a valve nnl' ^^ '^^i **" *^' ^^^^''^""^ extending from the horizontal part of thelipe/up inTthp^iJJP^"'^' ' ^',arepip4 which p,pes have valves at their tops, alsoTpeiing ipwald mL^'t."^''''^' ^."i ^ scends, the water in the tank forces ou the air containSTwrt**.; .t^ the vessel h de- m ; but when that vessel rises again, the valve ^bp^^ m ? lu^ ""^'"^^ «' *^« ^^^^e the pipe e, through the pipe /. The same take^^l.^^^ ]u^^^' *^^ ^^' ^^ ^'"^^^n from .ir in its descent is expelled through "Lvalve^lnnS '^^.r'^'^ »'» ^^^^ which the through the pipe /, from the Di^eL^hJ^\^J' "^' '" •**,' *'<^^"t' ^''^ws the ait in the pipe .,., and the tube J c to sunnlv wWh" *V* PP^^^l ?J»«««tion is effected force through the long opening of ihe Zlfl ^\ ^^^ ^'' '"'^^« ^'^^ considerable gas-burners! The bobbfnet ifce or Xr ^rS^f ! •""'' ^^'^ ^* *»^^ ^^^^^ «f *»>« between the burner 6, 6, an? the eihauste^^^^^^ h'"" "«^ j^^^wn over the flame the flame of the gas is foLd through L'^.' '.'■ ^^ "/*"' of rollers, as above said, filaments and loose fibres of the hiead arl burn 'nT''-.K^ '^' ^^^"^' ^"'^ ^" »^« fi"« the goods. *'''^^*'' ^^^ *"""* °ff» without damaging the substance of suspended by a cord or chaln^'ssU ov-^^^^^^^^ ^" ^.l^ ^^"^^ ^^ ^ IS also a scraper introduced inio the lube c which k m«2 I ^^ ^ ^^'^^^ P' There to revolve and slide backwards and forwardrfor th.T*^^' ^^ *7 convenient contrivance, ler that may arise from the /oX^sinTed aj^d ' l^^.V^^^^^^^^ of removing any light mat! passage. Two of these draught tubes rmav Zlf ^^^ otherwise obstruct the air apparatus, when a double row of burners T/emni^?^ .*"? ""^^"^ ^« '^^ exhausting may be directed upwards, downward or ./I?^^''^''^' ^5? ^^' inclination of the flame in the draft tube, by which ransaS'^i^^^^^^^^ ' -'^' '''''''" "^ '^' '^^ both sides at one operation ^ description of goods may, if required, be singed oq The greater part of the bobbinet lace made in England, is sent to Mr. HaU's work^ SLATES, w™'!^!"^" ^*\"^°«H°^ t? ^ singed; and at a reduction of prices truly wonderfiil SKIN (Peau, Ft. ; /fatt/, Germ.), the external membrane of animal bodies, consists of three layers : 1. the epidermis, scarf-skin, (Oberhauty Germ.) ; 2. the vascular organ, or papillary body, which performs the secretions ; and 3. the true skin, (Lederhaut, Geri.), of which leather is made. The skin proper, or dermoid substance, is a tissue of innumer- anie very delicate fibres, crossing each other in every possible direction, with smaU orifices between them, which are larger on its internal than on its external surface. The conical channels thus produced are not straight, but oblique, and filled with cellular mem- brane ; they receive vessels and nerves which pass out through the skin (cutis vera), and are distributed upon the secretory organ. The fibrous texture of the skin is composed oi the same animal matter as the serous membranes, the carlilases, and the cellular tissue ; the whole possessing the property of dissolving in boiling water, and being, there- by, converted into glue. See Glue, Leather, and Tan. SLAG (Laitier, Ft. ; Schlacke, Germ.), is the vitreous mass which covers the fused metals m the sroellmg-hearths. In the iron-works it is commonly called cinder. Slan consist, m general, of] bi-silicates of lime and magnesia, along with the oxydes of ir^ and other metals ; being analogous in composition, and having the same crystalline form as the mineral, pyroxene. See Copper and Iron. SLATES (.^rdoises. Ft. ; Schiefem, Germ.) The substances belonging to this clan may be distributed into the following species : — 5 6 uus cia» 1. Mica-slate, occasionally used for co- 5. Drawing-slate, or black chalk. 6. Adhesive slate. 7. Bituminous shale. 8. Slate-clay. vering houses. 2. Clay-slate, the proper roofing-slate. 3. Whet-slate. 4. Polish ing-slate. 1. Mica-slate. —This is a mountain rock of vast continuity and extent, of a schistOM domi'na!! *^^'°P®^^'* °' *^® minerals mica and quartz, the mica being generally pre- 2. C/ay-5/a^c._. This substance is closely connected with mica ; so that uninterrupted transitions may be found between these two rocks in many mountain chains. It is a simple schistose mass, of a bluish-gray or grayish-black color, of various shades, and a ahinmg, somewhat pearly internal lustre on the faces, but of a dead color in the cross Iracture. Clay-slate is extensively distributed in Great Britain. It skirts the Highlands of Scotland, from Lochlomond by Callender, Comrie, and Dunkeld j resting on, and r^dually passing into mica-slate throughout the whole of that territory. KcifinR- slate occurs, on the western side of England, in the counties of Cornwall and Devon • in various parts of North Wales and Anglesea ; in the north-east parts of Yorkshire! near Ingleton, and in Swaledale ; as also in the counties of Cumberland and Westmore! land. It IS likewise met with in the cqunty of Wicklow and other mountainous distrieU OI Ireland. All the best beds of roofing-slate improve in quality as they lie deeper under the suit face ; near to which, indeed, they have little value. A good roofing-slate should split readily into thin even lamince ; it should not be absorbent of; water either on its face or endwise, a property evinced by its not increasing perceptibly in weight after immersion in water; and it should be sound, compact, and not apt to disintegrate in the air. The slate raised at Eisdale, on the west coast of Argyllshire, is very durable. CUaving and dressing of the slates.— The splitter begins by dividing the block, cut lengthwise, to a proper size, which he rests on end, and steadies between his knees. He uses a mallet and a chisel, which he introduces inio the stone in a direction parallel Ic thejolia. By this means he reduces it into several manageable pieces, and he gives to each the requisite length, by cutting cross grooves on the flat face, and then striking the Slab with the chisel. It is afterwards split into thinner sections, by finer chisels dex- terously applied to the edges. The slate is then dressed to the proper shape, by being laid on a block of wood, and having its projecting parts at the ends and sides cut off with a species of hatchet or chopping-knife. It deserves to be noticed, that blocks of Hate may lose their property of divisibility into thin laminae. This happens from long exposure to the air, after they have been quarried. The workmen say, then, that they have lost their waters. For this reason, the number of splitters ought to be always proportioned to the number of block-hewers. Frost renders the blocks more fissile; but a supervening thaw renders them quite refractory. A new frost restores the faculty w splitting, though not to the same degree; and the workmen therefore avail themselves ! (I W52 SjVIELTING fllj I ktrtTawr^ ^^^""^^ ^ Succession of frosts and thaws renders the qoarried Hoclfs quit* k» ti^'lf ''^'^ *"" '^'''^^ ^"^^^ '^ * ^^^*y ^«ck, containing a great proportion of ouartz te which the component particles, the same as in clay-sllte Sd m^aSate Imt in^' Cerent proportions, are so very small as to be indiscernible. ' imti^. w *"^''"'^-, r^'^'''"' c^a«»-yellow, in alternate stripes ; massive • composition «npalpable ; principal fracture, slaty, thin, and straight ; cross fracture fine ewS^ S ft^Ki "'T'' ^^^"^^' little, if at all, to the tongue; is VCTy%oft Sn«^ into til LT't^"" ^i^""'^^ }"" ^^^ ^^y state, 0-6; when imbued with moSureiT' It S •apposed to have been formed from the ashes of burnt coal. It S foun d'at Pl«nit? •ear Zwickau, and at Kutschlin near Bilin in Bohemia? "^ "^ ^^^"'^^ ^c;i„ K T'"''"*^'']''' ?/■ ^''''*' ^^"'*= ' ^«s » grayish-black color : is very soft sectile easily broken, and adheres slightly to the tongue; spec, ffrav 2^1 The .tr?«b 5 glistening. It occurs in beds in primitive and tranWirclf^slkte alsJL seco\^^^^^ iZTlZ ' ^' '"^ ^^^- ^°^l-^^as«'-es of most countries. It is used n cmyon drawing Us trace upon paper is regular and black. The best kinds are found in SpaTn Italy and ^ ^/''"'/^r^.^'^'V^'^^ "^^"^^ ^^'^ '" Caernarvonshire and in "hSid of Islay ashinfn^s'jrk 11^'' *>"^' peenish-gray color, is easily broken or exfoliated, h« a stimmg streak, adheres strongly to the tongue, and absorbs water raoidlv with th^ emission of air-bubbles and a crackling sound. ^ ^' ^^^ Kit;;rr,o''"'"uT* '^""^^^M » species of soft, sectile slate-clay, much impregnated with bitumen, which occurs in the coal-measures. impregnaiea wiin inhfJft'f''^'^^^ a gray or grayish-yellow color; is massive, with a dull glimmer- ing lustre from spangles of mica interspersed. Its slaty fracture approaches at tCTto earthy; fragments, tabular ; soft, sectile, and very frangible; speciKravit^ L-fi I? ?s ?S '" ''' 'T^"'' ""' f""^'^^ ^°^" when immer'sedfor some ti^rii^waln nnSer"pxTco" t''Th?n^r^^ coal-measures. (See the sections of 7hesirata fi^efrom w:L .^*^^" 5'^eathed upon, it emits a strong argillaceous odor. When free from lime and iron, it forms an excellent material for making refractory fire-bricks ^mg an infusible compound of alumina and silica; one of the best exSefof wh^^^^^ •^UT Tni^a'' Hn?"^" ^^ ^^ "«°^^ of Stourbridge clay. examples oi wnich fomiati^n "^""^ ^'""'' ^^ **"" ^^"""^'^ "^°^" ^ ^^^^^ ^^^' of more modern SMALL WARES, is the name given in this country to textile articles of the tane fand narrow bmdmgs of cotton, linen, silk, or woollen fabric; plaited S!h ^rdbm? Ac. Tapes are woven upon a loom like that for weaving ribl^ns, wh^ isTow J^t rally dnven by mechanical power. Messrs. Worthington and Mulliner o£"ed a pftent 2:^^V 'f"' "' '^Pro^-rnents in such a loom, which have answered the pu^^^^^^^ then- large factory ,n Manchester very well; and in May, 1831 Mr WhiteheaTof th* «me town patented certain improvements in the manufacture of Jalwar^' '^'^ ^bjects of the latter patent are, the regular taking up of the tap^or cbS as it ij woven, a greater facility of varying the vibration of the lay. togethe? whh the ivhi^ of tsMALT, see Azuee and Cobalt. SMELTING, is the operation by which the ores of iron, copper, lead ft and adhere slightirto tlie t3 m which state it is withdrawn from the furnace. The roasting pror tL poC?M T^ hl^il blast would not excite the requisite heat to reduce the ore? and onrtl^TwerM has the effect of fusing the contents of the hearth into slags. In ihis pardc^ar^no cer ta.n rules can be given ; for the same blast is not suitable for every L?etrof ore Soft free-grained galena, of great specific gravity, bein? verv fuaiblp La TS J j quires a moderate blast ; while the hLer a^Syer WiS In all cases, it is most essential, that the blast should Se no more than sufficient tnr?l!.o -The blast should be as much divided as possible, and made to pass throu.^h ever^Dart nlrt nf ^r"'% ^^"•^— The hearth should be vigorously stirred, at due fntervall ^nd lit U K J^"^^'^*^ «^P«««^, "P«" the workstone ; when the partially fused lumns should pfcS out Thi'^s tS ""? ''• " "*^"^. ''' '"'■*^^'' -t"fied.^so as to^form slag"^^^^^^^^^^ So ^ L- ; u ^^^^^'""S^ Pjeces, and exposure of the hottest part of the br. uze u^n itr^ """f ' ^^- ^ "^f' ^""^"'^^ ^^^^t i° promoting its reductionlto lead for C atmospherical a.r immediately acts upon it, ancf in that heated state the sdohur is r.lmt ItT^^fZ '"T^'f^ ^"i" f "^P^T""^ acid, leaving the lead in £ metal icstlte het^ It IS that the reduced lead always flows most abund^tly out of the hearth irrnnedSv take place, when it is considered, that n smelting bv means of thp orl v.o{.!i •! f ^n,ai„, impedes the smelting procesa. and in™ tL quiw;':fICs ^;e^J^ difference of composition of perfectly dressed ore ma^ rp^,in« ki ? ^!* j ^®1 *"^"^ reducibility; and hence it is, Wore froTdlffereH^^^^^ ^^ f :^"' '''' strata, as before observed s freauentlv fo3 to J!l ' the same vein m different singly in the hearth. It ha^peLTherl^^^^^ ^**«" «'"«'t^ of ore require more coal anTlim;, and a ^^^^^^^^^^ Cee oftatThan^'othp""' 'T^'' for this reason that the forestone is made moyeabirS 1 eitW 'tn ! 7 ' """^ t ? works with a large or small quantity of brouze ' ^''^'^^' ^'"' ""'^ ""^'^^ en^or.^^:l^:':^ety^^^^^ 'o 15 hours, at the necessary to stop for some tlV^oTder^^^^^^^^ ^^t. and it is shift is 12 hours, the hearths usually go on 12 houM ^d .t ZVt ^^/ smohmg half or five bings of ore (36 to 40 cwU are smpUp/S «"«pended 5 ; four and a who manage the hearth each work fo,7r«h?ft! n^ ^, ^"/'"^.^ «hift, and the two men at 8 o'clock on Wednesly aftr^tn^^^^^^^^^ terminating their week's work also work four 12 hour shifts ThTla«tnfU-wf''^l^^ ^^ *^^ «*^«'' ^"^kmen. who In these eight shifts, from' t toto btgsVo'r tll^^tef w'Lic^ 7 "r'^T- ity, produce from 9 to 10 fodders of lead At JhL ^^^ J^^^^i ^'^^n «f S^^^^ qual- hours, the furnace is kindled at 4 o'clock in tl ^1"- '"'"" J^^""^ *1^« ^^'^^ ^^ 1* or 15 evening, each day, six days in the wee^ t-^g th^^^^ lftT''''*KrK- ' °^' '" **^« smelted, and two men at one hearth in the elrW *«! r ' ? *"" ^f ^'"8^' ""^ ""'^ *™ SMELTING. 655 ^ii^T"^!-^^' '^ P""?^^ •' 'P. «*>°»e cases the quantity of ores melted in one hearth, ia a week, by four men, is 40 bings; but a fair rate of forking is from 30 to 35 bings per ^J^t '^•'Jw^K*^ °^ ^^^ required to smelt a fodder of lead, as has been already stated. ter b^i;^^ nt T'^l^ "^ h ''': ^*^"" t^- ^^"^^ i^ «f °^«d«rat« goodness, 8 Winches: ter bushels, or 6 cwt. avoirdupois, are sufficient to smelt 18 or 20 bings: but when the Tto lVw?nfhp7tp I' \T'''/ ''r''i '' ''"^ considerably greater. ^In general, from W shifts 19 1 ^u ^^/''^^ «•• fr«°» ? to 9 cwt., are consumed during four ^melt- {o^stdder^ fl^ri'^'^' ^°^'.^ ^^f ^"^?^^'^ ^^ ^^^^ "^^^^^ d»^""g this tim°e is from 4^ to 5 fodders, the coal consumed is after the rate of from U to 2 cwt per fodder The quantity of peats used in the same time is about four small cart Gs, being som^^^ fchl^" ^ eart load per fodder of lead. The lime expended is aboit 12Vrchestef bushels, or something below 3 bushels per fodder of lead. mcnesier otoTeteZhliil^^'"^ ^'"^K-^T?.^ slags picked out of the brouze during the process ?; ?;^P^^^^ smelting are subjected to another operation, in what is caUed a slag hearth It 18 simply a square furnace, open towards the bottom of the front side. Its d^ensfons are various, but a common size is 26 inches from back to front, 22 inches broad and sl nches deep, inside measure. The blast enters through the back wTaW 12 or it mches from the top, and below this, as the heat is incoSiderable. the sides o^^he^urn^ SLrts nf ^ T'^'.f "^^ "'^'^ (at.working smelting-houses old bearers, or other w^ &tensP fhp r^^'' f ' econonucally used), but above the blast, where the heat S Plate 2 inchP« fhJ.r ^?'°''/ f '^\^ .^^1 '^^'^'^'''^ ^'^'''>''^ ^' ^••^^"^k. A cast-ircJS A (Lst iron ^L . ^ Pr'^i *t a sbght slope outwards, forms the bottom of the hearth. thZh 5 ; ^ P^-^"^'^' ^''"°' '" P^^^^'* «PP««i^« to the opening in front, one lip of Jhich ,s made to project inwards towards the furnace, and to extend a little befo^the trSn rpt°^ "^ '^' ?T'-; J^'' P"" '« ^'^'^^^ ^'th two compartmen s!by an iron partition, reaching nearly to its bottom, and is kept hot by a small fire underneath Below the front of this pan, a square pit, 6 or 8 feet long, and 4 or 6 feet broad and deep is duff P pes to convey water are lafd to this pit, by which it can be kept constaDtfy^^^^^ Within a few inches of the top, when the hearth is at work. ^ follows :-^ "'""^ ^* *^^ '^*^ ^'^''^ ^' "^^'^ ^°^ ^^^ '"^thod of working it is as ♦I, J^^u^'"^u- u'^'iu °\*i^ t^® ''■°" P^'^' *"^ the whole space of the hearth below the orifice itepH?*'''^?' ^}^' ^"'"^^' '' fi"^^ ^^th cincfers of a moderate sizi, genemlly obtained from below the grate of an adjacent reverberatory furnace. Upon the top of whlTf r '"^ «PP««'te to the nozzle-'of the bellows, a kYndled peat is K and^hl supplied l^thT£f' L^v °^ '?' ^"'^> ^"^^ ^''^ P^^* ^"d ««i ^^"<=h is continually du^A ania ho5v of f '^1?/ '^^^ fJ^' ^^ ^'^' ^«"^^' ""^11 an intense heat is pro^ duced, and a body of fuel obtained, filling the upper part of the hearth Some of the g-ey slags from the smelting hearth, untroken, Tpik'ed out of the brouze are now i^inr^ T J'^' «r rather round the edges of the fire, which fuses them rar^dW^nto a hquid glass and any lead they contain is set at liberty ; the blast at the sSne time h?ih^ t/1"'5 -»7 P.-'-tieles of ore which may have escaped the action Tthe ore Sprf i«. H • tu^^^''^ '^' ™"^'"^ ^^^'« ^th sink down through the porous maL of c^! tZ ^r f -r ""^r P^^' ^^ V^^ *^^*'th; the lead descending more rapidly l^th on account of its greater tenuity and superior specific gravity, very soon collect below the cinders, m the metal pan placed to receive itfand filtering^\hrougMsTSed without much impurity, out of which it is cast into pigs. The thick fluid XHrrfllpJ WaS a 5ftu:'do;sTo iktxf rt '^"^'^:, i '^^'^-r^' ^-^nX^^^^ a uttie does not sink further, but is made to issue through a small taphole and flow stream ' By'riliS^:hire ti^'^'t' ""^^ ''^^ ^^^ P^* ^^'^^ ^^^ ^^^^^ "°tinu^ ol.on % i? ^""® ,*t »"to cold water, the black slag is granulated and. aa small particles of lead may be carried over with it, through inattention on the Srt o7 mmrw'"^°>; •' *'^,?^'-^»««' the granulated slags ar^ carefdly washed at most s^eltinl earthy matter contained m the ore and coal, which the metalUc^oxides Tnvert bto a In workinjaslag hearth, the workman's attention is principally required to .upply gray slag an J fuel as it is melted down and consumed, to keep the Lzz^e of the iSlows clear, and to guard agamst the metallic lead running 'along wVthe sl^ Tnto the pit Tf « K^r^rTlt'lT" ffl^ r°»Pj«yed to work a slag hearth, but, at some mills, a man and Jt^J« V t «"^''«"*' the attention of one is wholly given to the fir; while the other supplies coke and gray slag. The length of a shift is' 14 or 16 hours, during which ' Ill 656 SMELTING. 8lag lead made in smelting. alWbL conceived i^^ ^ v.'^"^' ^^ q"»ntity?f refractory than in rich anlfree-mn^ninl orel hJ' t '^f^^^'^Wv greater in poor and thirteentii of the lead yielded at theTe^Itinff hearth so S ^,/*"'i .^""^"^ ^* «°«- transactions. 13 twelve-stone pigs of commof lead and 1 rJ j! '', "'?^ ^ f ^"''«°' '" W« . i^.«r^A JEnds and Smelter sl^e.l-^Z oner'at^on of Ir^^- ^'^''' *^*'^" ^°^^^^- it happens that particles of unreduced and «!mF!I3 L smelting, as already described, the fe^rth, partly by the W o't'SLrb^^^^^^^^^ ore on the application of heat Thi«, ^ITL ^- P""*^!P~^y ^7 t«e decrepitation of the made use of m^meltingauS which arTd^^^^^^^^ ^r'''''. \^ ^^^ ^"^^ «"d ^^^^ and are called hearth-^ds. It -^cusiZlrfrre^^^^^ ,1 }^f '"^'''^^^ ^'^^'^ and deposit them in a convenient place Si the Tnd of the vilr 1, ^ ^'"'"V"'^^ ^« ^'"^"^ when they are washed to get rid of the ear hv m^fl !k1 ^ ' .^""^ '^"'■^^^'^ P«"H portion is roasted at a strong heat untini hL^- . they may contain, and the metaffic Afterwards smelted in th^ofeheaVtrexa^^ ^°^ ""^^^^ ^"*« ^""^P«. and operation, for the first time already des^S '"^ ""^^ ^' ^""^ undergoing that giv^n\1fntUy oro*^%ttrL\^°1:iyi^^^^^^^^^ T^^^ ^J t^e smelting of a biBgs. on being roasted and reduLdTthe orp hp«r^^^^^ produced in smelting 9^51 and the gray stags separated L th" p ^t ^ve by tr^Sme^^^^^^ of slag lead ; making the total quantitv of lead '^fi9 Zi^^^ I- * ! '!^ ^'^^'"*^' ^^ ""^^ qrs. 23 lbs. from the smelting oriJSbfngs o^^^^^^^ ^^" ^^''^ " ^^ *^" '^^^ «^ ^ cwt 3 frollhl'rLtTfltfo'r^^^^^^^^^ ^\"'^^:: ^^•^ «°^«^« -°d metallic vapours, of some time, a fo'^ourd^"^^^^^^^^^ ""'^^T'^^'^ ^^"^^'^' ^^ *^^-^ and. probably, also of sulpKate of ead whi.h L^f k 'i ^" v ^ ?''"'''*^ °^ sulphuret. cesses, mixed, like hearth-ends with a n^kv nf ^f"" ^°^f Jihzed in the diflFerelit pro! used in smelting. It is eenerX sufferS^^ ^ ^ earthy njatter, from the Ume and coal until the end of^ he yea?Xn^t7s wSLeS ^""^^^^^^"ther in or out of the chimneys^ residue is roasted unti? H^heres Tnt^lumns «nT^^^ u^a ^^'^J^ T^^''^ ^"^ ^^^ ^^^^7 the same way as gray slags t£ quint tvo^fLl^^ln '" ?f '^^ ^'""'^^ ^^^"y ii deposited in Wltin|975Vbi^8 of ore %^ t^l^f ^w "''^. [T '^' '"^'^''''^ ^""^^ 14 lbs. of lead per 100 bings of or^ ' ^ ^^^ '''*•' ^^"^ ^* ^^^ '^^ ^^ 5 cwt qrS quInUtro^^eXS :^::^^^^^^^^^^^ ^« considered invariable, for the ends a/d smelter's fume, from a S^e^^f^^Xt^^^^^^^^^ ^^"^ '^^^^ *« time by the hearth- d^p^s .Oder c„.ide.tio„ „« ,U.e., to^g^.^LiLt ^Z% 'L?S iSIS^' Correspmdenet of Proiwe with Atsav.—As the amrftino. . • •• i, m.sm^agement. through inexperience ofimuLtil TThe laHf V^™ ' *" ^*S' men, it is a matter of eome conseouence to l-r,^^ K^ ^ .1 ^ ,. ® *«''"'' ""■ ^o''k- by smeltiug in the laree A cSotdcTs with Z„ .^ f ! ^ '^'^^^'^^ "^ '""• °'*»i°«J o|^ra^d uV, and/r thia'puTpS^Tu ra'.^*ro'^^^ro°hl^ve~rtl^ sampled and aesajed prior to smelting. The pureet ^lena?a a eom7o™d?f ""'''' 1 atom lead, 1 atom sulphur, - 13 2 15 86-66 13-33 99-99 Wr^e^tTfir^slTr Sr^'r'l-n^'Tl^iT a"^ T^''^^" *" '^ ^^r- piece of cubical galena, by treatLent^th bi™^ Id ,»h ^ ^,i^r^ "■"" » ""^ P»" awayer. In the large 4y leaTore if seE^l In ' '-1 ""^ ''""'' "^ *" «peflenced yield more lead to the assay tton 77 or 78 ner cenr n "^ P"T' "'"' '''"^' ■"" "f*" of lead, contains, besides, protebly, 4 oje'^^r «„t ^L^^^^^-^ ^J'" " P*"- ««■"■ before reduction in the prOTesa of a,«vlna.TrL.-;f "oxidized, or volatilized, is only made to its absofute p^oSnceX ^y no ,S^ d"L'''' "^^'^'a f V'""P'<'' '"^""'"^ tity of lead it may contain ll^jond IhT^ST/p^duT ^"^ P'"* '° "" f°'"'"« I"*"" asiXrs^i^^Jrtli'e'ltii^aS^ru*^ l-flj "^ "l"" '"'"-'^'^ "^ the allowance is to deduct 6 parrffoKe^ro^S^rV?^ ""^ "?"'• ^ «-"t<'«'"y alent to making an allowaniTl cwtT^Kr ."""? P"',' "^ ^ V''''='' " ^q"'''- -lowance of /or 3 per cent.. orUrT^ ll^^'e/^rSIstt lrfor"mSU''S.hS SMELTING. 657 •r«i, when weighed over at the mine, as the sample assayed is, in all cases, perfectly dry It is found, in practice, in almost every case where a large quantity of well-dressed ore is skilfully and carefully smelted, that the allowance of 5 parts of lead from the assay, or 1 cwt of lead for every ton of ore, is rather more than sufficient to cover the loss in the smelting process, without taking into account the lead obtained from the hearths end« and smelter's fume Refining of Lead. — The quantity of silver contained in the greater part of the lead raised in the northern mining district is sufficient to render its extraction profitable, and it is of the greatest importance that the process of refining should be performed in the most perfect and economical manner, in consequence of the enormous quantity of lead continually submitted to this operation. It is well known that the separation of lead and silver is eifected through the difference of oxidability between these two metals, silver remaining unaltered when exposed to the air ot the atmosphere at a high temperature, and lead, wider the same circumstances, becoming rapidly converted into the state of a protoxide ; which, when formed in the large way, is called litharge. The refining pro- cess is therefore performed by exposing the lead containing silver to a strong btast of air, at a high temperature, in a furnace properly constructed to allow the iftharge to separate as it is formed, and to admit of the continual introduction of lead as the operation proceeds, and the ready removal of the cake of silver obtained at the end of the process. The furnace for this purpose is called a refining-fumace. It is a small reverberatory furnace, the fire place of which is very large compared to the size of its body, rendering it capable of exciting an intense heat Some of the objects to be attained in the con. struction of this furnace already stated, render it necessary that its bottom should be moveable, in consequence of which an open space is left quite through under the body of the furnace, from back to front, which is formed by two walls of brickwork. The distance of these walls in front is 36 inches ; but they approach together at the back of the furnace, and the space between them is but 28 inches, which, to prevent a draught of cold air underneath the furnace bottom, is closed with iron doors. At the height of 16 or 17 inches from the floor two strong iron bars are laid across between these walls and firmly secured in the brickwork at each end. Above these bars, and at the height of 27 inches from the floor, a plate of cast-iron, having an elliptical opening in the middle, the transverse and conjugate diameters of which are 46 and 28 inches respectively, is laid across, from wall to wall. Instead of a square plate, a broad elliptical ring, supported by bearers, is sometimes used; but, in either case, the brickwork forming the body of the furnace, is built upon this plate, and is made to extend to, and surround, the edge of the elliptical opening; except a small aperture in front, 6 inches wide by 9 inches high. The two flues communicate with the chimney, and in other respects, except those to be after* wards noticed, the furnace is finished in the usual manner. The bed or bottom of the furnace, when in operation, is formed by a shallow elliptical vessel, called a test or test-bottotn, the construction of which merits particular attention, as it is an important part of the refining apparatus. An elliptical iron ring, 4 feet long 2 feet 6 inches broad, and 4 inches deep, outside measure. The thickness of the iron ii 1^ of an inch, and across the bottom of the ring are five bars, each 8^ or 4 inches broad, and i an inch thick, firmly rivetted into the ring, with the under surface of each level with its lower edge. The ring is filled with a mixture of one part by measure of fern ashes, and ten parts of ground bone ashes, well incorporated and moistened with a little water, until a small quantity, when compressed in the hand, is found to cohere slightly together. In filling the test ring, it is placed upon a level floor, and this composition strongly beat into it, with an iron rammer 5 or 6 lbs. weight (similar to those used by founders for compressing sand into moulds), until it is quite full, and the surface of the mixture perfectly level with the upper edge of the rin^. A sharp spade is then taken, with which a part of the composition is removed, so as to form the test into a flat dish. The bottom of this dish is about If inch thick between the bars, and the breast of the test is 5 inches thick, the remainder of the circumference being 2 inches thick, and sloping inwards to increase its strength. Across the breast of the test, a furrow or small channel, called a gateway, is cut diagonally, 1 inch wide, and | of an inch deep, as a passage for the litharge ; and it is made near one side of the breast, in order that a simiUr passage may be cut on the other side, after the test has been some time in operation, and the first gateway has become worn down by the stream of litharge. A space 1^ inch wide, and 7 or 8 inches long, is cut out between the front of the breast and the test ring, in order that the litharge may flow down from the test, without coming in contact wiS the iron. Instead of bone and fern ashes, mixed together in the proportion stated, it is a better practice, and one gradually coming into general use, to make the tests of a mixture of one part of the best American pearl ashes, to forty parts of bone ashes, by weight Tbe pearl ashes, reduced to fine powder, and perfectly dry, are thoroughly incorporated wi'k 24 rn 658 SMELTING. Uie Done ashes, and the compound is then moistened to the proper dcCTee with wat«r after which the test ring is filled in the usual manner. FroHTo F^Tunds orue^rl Tlie test, thus constructed, is apDlied to the onpnm>* ;« ^v^ • i x When the test is properly fixed in this situation, and thorouffhlv dried hv the applicatmn of a gentle Ut, it is ready for the reception of lead, which s poured into it with aniron ladle, through the chaimel. being previously melted mid kepT nearly at a etl A mode" o'fleedt ''"tl ' r." -^^ '^^^ '' '^^"^^^^ *« «" ^ "^^ ^-^ to t^e wo^rk „^ a P^ of lead or 1 it„ 3 K? J^'' '' f "betimes practised, which consists in suspending t^Jlu ■ ^/.^ V°° Y^'^}"^' ^^"""^ * ^^"^ »^^e the melting pot, by means of a chain and a owing ,t to dip into the melted lead when made to dfsSnd, lo ^^o W^ ?S ead displaced by its introduction directly into the test through the 4an^el wL^hi^ that case must be a little lower than the lid of the melting pot Some ^fin n/furnaces a e not constructed with the channel; but, instead of it,^hayinc. an openL [nX buck- work of the furnace, on each side of the test, through one of whtch aChol! nl^? kad IS introduced and gradually melted down into the test by the heat of the^L ^S^slTe of i;r*;'V"' ^-«^.^r« *» t^^^. - the lead is consLed. An op^ Jnf^n fnTrod^ cpd nn^^ J " considered necessary, in order that the lead may he always !.nL^?if '^°.*v^"'^^ ''PP?!*^ *^ *^^ gateway working at the time to prevent the Ent ^t: te a^d"!n"om' ' ^^'^ ^*TT' f '"^^ ^^^ '"^^ breaTt ofXtest n t ^uant vnflln'^^ 'fi A^^ instances, to be afterwards mentioned, where so large a 2.oT- ^ ? A^^^^ P^°^^ *" * *^^*' ^ *« '■^n^Jer it necessary to have three ffatewavs the L at wort "''^ '''"^'^ '° "P^""^ ^^""^' ^"""S *^^ *^^« that tie mifSirga^eway The last part of the refining furnace to be noticed is the aperture behind for the maXneTv tSi^^'^T '• f Tf^^^^ ^^' ^ P*>"«^^"1 ^oub^e l^Uows, worked by machinery. This aperture is formed by a conical iron tube called a muzzle walled into ll 1 "fr'Lfr"''"^ '^" ^^^ "^ '^' ^"'^^^«' its larger end our^rt^eS es The of the It is^nTl' "'^ ;^^^,T'"'^'"^ P^^J^''"» ^^^^ ^^« fumace,ove the inner ed.e A J r 'uf bent down slightly, and its orifice compressed into an oval form so m tn deliver the blast with sufficient force upon the surface of the lead and at the same Tin^ to spread It out towards the sides of thftest. Much care is usSSly^rtowed upon the construction of the muzzle as the proper direction and distribution of ^e blast i/a po\nt of great consequence to the working of the furnace * ^ Refining furnaces are generally built double, that is one on each side of the upright tTZV ^j;*' ^^.^^P^'"^^" t»^« d'r<^tion of the draught, and consequent sLLfffhe fire-places, there is no difference whatever between them. The fume\nd smoke from b^th from Th?^'^ r*" ? ^^^'''"^ "^ ^}' ^^^'•^^^"^^ fl"^' «^P^^te from that con^g theTmoke fo mil He?/ h ^ ^r^"": T ^'^'*^' ^^ '^^ ^''^^^^ ^i*^ ^^i^^h they are n^ot suffered • oxide of Tead. ^ ^^' ^ ^^''^ ^'^^ P^^^"'' "^^^"^ '"^""^'^ ^"'"^' ^^<^»^ " principally .Jo*f! *5^t j)emg properly placed in its situation, cautiously dried, and filled with lead as already detai ed, is exposed with its contents to the flame passUig over ^ ^til tS« lead attains a bright red fcat, at which period the blast of air ifm^e to plLv^pon^t^ rnronp/J'r oxygen thus supplied rapfdly produces a stratum STuid li&eThich 18 propelled forwards by the tlast. and forced through the gateway, over tKre^t of tream' ' C fc^"^ supplied by a fresh quan^tity. so\s to ^e^rup a conUnuaf time W thVt I ^ • ^';?''^*f« »"*° 1"°^P« ^ »t falls, which are removecf from time to of ll^T ! 1 workmen in attendance, who take care, by the addition of fresh quaiTitie^ of lead, to keep Its surface in the test always at the proper working level UZwa^ the operation proceeds ; but as the hot litharge gradualirwears down tC^atewlv Jt^ t ^Tuf '?' ':'' r^P"^^^ '^ ^«^^'°S * «"ffi<^'«"t quantity of eaH b^^omes ne^;rar^ to make a fresh gateway, generally after two fodders of lead have been refined wS ^js IS done, the blast is suspended^ the old gateway is topped up^^th a p^t of^ne ashes, a fresh channel made on the other side of the breast and the test fiutr? ,?« w^?K mnre'%'l ' T^' K^'^' "^? ^"^^ ^^' ^'^'^ then proce^^agLIn, un^ more of lead have been oxidised, when the second gateway being also worn down „ntfl the test does not contain more than one cwt. of lefd. the Wge^s T^po^n^ ^b^^^^^^^ are slackened, and those in front taken away, and the fluid Wrcalfe^^lSi^Uv rich four' whLT'^ Th° "\T r' '^ ^"^^^^ ^» ^i^«^«^' r-"i4' upo;\'':LX^e^;^S four wheels. This rich leaJ, containing the silver of four fodders of oriS T^«A (usually from 30 to 4o ozs.) is cast into a pig and taken awa^ : a fresh test is aT^^ the furnace, and 4 fodders of lead worke/in it, in the manner described! VntiW or lo SMELTING. 659 pieces of rich lead are obtained. A test is then made, the bottom of which is somewhat concave, instead of being flat like those already mentioned, and in this the rich lead is carefully refined, yi;eWin^. at the end of the proce8^ a cake of silver weighing from 1200 to 1800 ounces. IJe rich lead is treated in the same way as ordinary fcad, except perhaps more carefully, and after the last piece is introduced, the gatewayis made deeper with an iron tool, from time to time, as the surface of the lead subsides by its gradual conversion mto litharge ; and, from this period untU the cake of silver is rendered pure aU the itharge then flowing is kept separate, as it ia apt to carry along • with It a portion of silver. The part received is caUed rich litharge, and may contain on an average 20 oz. of silver per ton ; it is generally worked up at the end of the year by being reduced into lead and again refined. As the cake of silver becomes nearly pure, It is most essential to keep it constantly in fusion, for if ooce suffered to solidify It 18 very difficult to excite a sufficient heat to melt it again. The fire is therefore urged with great violence, untU at length the whole of the lead being oxidized the formation of litharge ceases, and the mass of melted silver appears pure and beautifuUy resplendent At this stage, it sometimes happens that drops of melted slag from the rurnace roof fall down upon the fluid silver, in which case they are carefuUybrouffht to the edge of the melted metal, and raked off upon the naked part of the test The blast from the bellows is now stopped, the fire is slacked, and the silver suffered to cool • winch it does, very gradually, first at the surface, forming a solid crust over, a portion remammg fluid below. When the temperature has fallen sufficiently, this also becomes 8oad, and in the act of doing so. a large quantity of nearly pure oxygen gas is expelled irom It, and at the same instant its particles expand considerably, so as to break the crust already formed, and force out a portion of silver, to the height of 3 or 4 inches above the rest of the cake. Occasionally particles of melted silver are projected out of this mass, to a distance over the naked part of the test, and the sides of the furnace, by wl^ch a loss of the precious metal is sometimes sustained. After having cooled sufficiently, the cake of silver is removed from the furnace along with the test from Which It IS then separated without difficulty ; and if any slag or portions of the test are lound to adhere to it, they are cleaned off, and it is ready for sale. During the working of each test it gradually absorbs litharge until saturated and the portion thus combined is sufficient to pay the cost of extraction. For this purpose the o d tests are broken to pieces, and smelted in the slag hearth, mixed with a portion of black slag, m order to render the bone ashes more fusible ; the black slag used beinff run into lumps for the purpose, and not granulated in the ordinary way. The produce of this fusion IB a description of lead called test-bottom lead, which is very hard and of mferior quality. j ^ » »i The deposit called refiner's fume is removed from the horiiontal flues from time to time, and is frequently ground up with oil, forming a very cheap and durable paint but the quantity produced is generally too considerable to admit of the whole being disposed of in this way, and the surplus is reduced by being roasted almost to fusion and then worked in the slag hearth, in the same manner as gray slags As mieht be expected, the lead obtained from the test bottoms and refiner's fume contains but a verv email portion of silver. ^ Instead of converting into litharge but 4 fodders of lead in each test, as already mentioned, some refiners are in the habit of working 12 or 13; but, in this case the tests are constructed with peculiar care, and the bottom, sides, and breasts are liiade thicker than usual. The litharge from 4 fodders of lead flows through the first gate- way made on one side of the breast, and when the quantity of lead in the test is reduced to about a cwt, it is cast into a rich pig ; 4 fodders of lead are then worked through another gateway, on the opposite side of the breast, yielding a pig of rich lead m the same manner ; and, for the remaining 4 fodders, a gateway is made across the °J! u j't the breast By adopting this method of working, the loss from the lead absorbed by the test bottoms is considerably lessened, and a great saving is made in the expense of tests ; but the process is rendered slower, as it is necessary to work at a low degree of heat. The saving in tests is not what it appears to be at first sight ; for those made to refine the larger quantity of lead, being thicker and stronger than the others, reauire a larger quantity of bone ashes. vjuuco, I A "^^^'A-^ '^^^"'"^ ''*'^''*? * ""^^' ^^^"^ *^® «^"8e just stated. When 4 fodders of lead are oxidized in a test, it is usual to accomplish this in from 16 to 18 hours ; and 6 tests, or 24 fodders of lead, can be very easily converted into litharge, in one furnace, by 3 men in a week. The quantity of coal consumed is about 4 Winchester bushels, or 3 cwt avoirdupois, per fodder of lead. In cases where 12 or 13 fodders of lead are refined in a test, it is customary to work but one test in a week, in one furnace, which is only Sf^: n.^"j?*''y ®.*?^®1 ^^^® ■' ^"' ^^^^ *^«0' t^'^ee men by managing 2 furnaces refine 24 to 26 fodders of lead per week. Reducing of Litharge.— The reduction of litharge into lead ia an easy process and in 660 SMELTING. being flat, is niade to^lope towards an^ o^nTng Tn SL thVc^^^^^^^^^^^^ r'ff ^i 18 conveved, bj means of a cast-iron channel into a not fn Ko f Ti 5^ reduced lead sale. The inside of a roasting furnace is Venerallv ml'dl ]L ^k ^. ""S?^ ?"*° P'^« ^^'• feet long and 5^ broad, and 1 furnace V^rS ^orLnrtSrL'"'^*^'"!' ?^"' ' shifts each, is capable of reducing, without difficilty^ the iL n^^-'^^T' ^\ ^ ^T' ing furnaces, each working six teste, or 24 fodders ^^r' week After S^r!^ ' • ^^^ ''^' has been properly heated, the Droceas io nnmmo!!nli i! -^"er the reducing furnace stratum of coal, which taking fir?^^ sL form?f 1^^ T'T^. j^^bottom with a thicknesa Upon this the chaLe of SffT^ed „n wfftf °^ '^T"^ ^"'? '""« '"^^^^ '^ is thrown, an^ a furnace of the sizfrneftio^ wm^i, u^ '"'*" ^"^^^'^^ «^ ^^sh coal reduction goes on rapidly and the ?^^T^ T"^ ^i^ i^°°^ ^.^^ ^^ three tons. The litharge, until the quant [y adld L S as wilT^^^^^^ T '^f *" *^'°^' ^^^^ fresh the charge is then suffere/ to run down wfthThl ?d^? %T V^ ^ /^^^^^ ^^ ^^^d; reduction, as it seems to ^ reoTred At th« ^A «? • ""^ ''^/'■^? *^°^^' *^ P'-^™^*^ the litharge is reduced, and S thrboln, of theTurnac^^^^^^^ '\' ^^«^« 9^*^^ s^,^called litharge slag, which is raked o'ul 'XTs^irh^tT^l^^/r °n"^^ is afterwards worked iver n the sSearth t^th W^ unavoidably united with it, it bottoms, yielding what ircaUed ffim? «w i ^ "?• u^?\ '" *^^ ^""^ ^^^^ as the test- ferior qiiity an^dlnta nsSe Jlv^^^^^^^^ ^'^' test^bottom fead. is of in- naed to mix with the lithLte in o^^^^^^ that th/ ^^ f^^°'^ *^^* l^^ ^^'^ ^^^^ «^«"^d be -nounted U, one thirtyseeond part oHhe o?§naI leld ^fi^ed "' ""'^ '"'"' '"S""""' undergoing the reYnbL S^^ts but' ?^ i"^° ^^ ''iK'^ *' *<"»' I"""'"? »' k»d the helrth%nda and" ^U?S^™'e W tt dee?^e If w't ^ ^K^^. T** i"?*fi«^ ''''« are worked ; it is therefore imDoJ blf ^rhf^IL > '■\'^^'^ *e refining furnaces ^.rrespond with experien^ r^^^^/^eTtlfeMUht ^^^ "''°'' ^'" «-«? to the profess, by tEg a Sip fr^ieJh „,V 3'"^.?* 'fl *° '^ '^^"'^ ?'«"<»>' ting a known 'weVt to^cupdfatiT UtZtZyhL^L'^t^^i^''^"' »■«' '"bmit- obtained in the large way isVater than thalSi»t.yr?.. *■"" «''\q"»""'y of silver is. that the lithargf, aa It sinfettotre smalt Pelea,?;^^^^^^ -"T" '"^'"='' •liver, rendering the button obtained rather le„flf.'„?r T. f v " ?'°"'* P""^'"" »' the litharge ab^rbed by the ^^McupSZlkZ^Z^'^^A'i^.^t;- *"" ^11"^'"'"^ refining this lead a second time, anothS minute bu«o?„'fTi* ''\^\^^^ ^ .bor", and to the first button, generally indicX a oZ,Htv „f .ii ■ fl ", °'''"°H which added with which its produce ta^rCTeat way^rhin^car^^^^^^^^ under examination, taking into account the sLu pSriiW unavoffl?^"*^^' ""^ ''-T'^ ""'""^es and found in all samples of XnedLad to tireXt^^f "f'.r^'' """^ "'« ^'^^"e"' per fodder. It will easily be «n<«ived that if the , In ^"K *" """'=« "> »'' »""<=« carefully performed at firsrwl^h" due deCT« of he^? Jr''' "' <="P«'l»«on has been theptMteS ^Llrfh-^uldt'^^ednr^ta-sf^ei'" ""^rr or 1 cwt. of lead for everv ton of oro a«^ w«r,u- V • if ^ ° P**^*^ '^^o"* the assay, e?err.7.r ■ ^/-^p"^- o-nr;^a§ teaVtiriry^^i firs?,Urc:f irli"welftrof?eZi.«^^^^^^^^ 'l "T''^ ^»«««"«'J- '■> ft" fume is melted up. and the fead extrS from the / ^.i.T''*'' *''« deposit of refiner's ultimate loss becSmes not more thS onelS^Sh a„d wiS? 1°""' »"d 'fthai^e slag, th. heat at which'The o,idatic„ wiSl t '^t^ V:^. t tiLVt.^^Tr^^-, "J SMELTING. 661 ind^TmW w!fh\t'f '''''?^ ^i^ i^ ^^^^ the particles of silver to separate from it. and combme with the remaming lead in the cupef; they are thus, as it were entangled ll'riaUySir™''''* ''"'" '"^ "'-'' "/"'"='' ""« P™0-i/slM SMKLTING IRON FURNACES, commonly called BLAST FURNACKS Several of these furnaces, a, mounted near Glasgow.^deserve to be made known on SSu olttirTem*"' "'"'""'"»"• '"* '«'^'-"^- of *'- fo-. -d'th" a^S^u^St ^^r. 1302 represents one of the smallest of these, which measures from thp Un^ of *».^ bottom to the top 48 feet, from which all the oth^r d meSs may b^ estimated U Tm'ZWil T"'''' I'' '""'^f into moulds and for melting?7the cu^ >V '* 1803. and 1304, represent a much larger furnace, being from the top to the liSe a b c d «0 feet high. A few have been built still larger. This furnace has a double case, each of which consists of fire-bricks. This case is enclosed by common bricks, and these by a wall of stone masonry, llie successive rows of bricks are laid stair-wise, having the aiiijular retreat filled up with fire clay. Fiff. 1307. is a modern furnace of verylaree cumeiisioas, as the numbers upon it show. ® ;n ^ If I,- "^P' ?^"V''^ «f the great iron works of Butterly and Codner Park in Derbyshire, has invented a very elegant and eflFective apparatus for fSngWs ^idLlirvHlJrl^/T^ mm. (cacined ironstone), and limes^tone Tdue prSon^ ?^d arJ itu ^i 130^^^^^^^ T^' "^ 'K ^"'•"^- ^^*- 1308. 09. rep^res^ this feed-apparatus, /^t^r. 1308. shows at a an outline of the furnace, and at b, the line of barrnl" n ^ n ^^ "' '' '^' ^^«^,°^«<^hanism. It coDsists of'a loug bilance lever a^ 2rfe«t in'hpia^r?n ^ ":°".^^yl^°d«»-' «pen at top and bottom. 4 feet in diameter »nd 2i feet m height, m the mside of which a hoUow cone of iron is suspended, with 662 SMELTING. It ^;m l! I SMOKE PREVENTION. 663 never, d, e. is seen m profile or vertical section; a, is the fulcrum wheel, upon which the lever is m equihbno when 9 cwt. of coals are put into the cylinder; thena weight IS hung on, near the end, e, of the lever, as an equipoise either to 9 or 12 cwt. of mme according to circumstances; and next a weight to balance one-third of that weight of limestone. These weights of materials being introduced into the cylinder, while the barrow rests upon a level with the line e d, it is then rolled forward into its place as shown in the figure upon the wheels, b 6, upon a platform sustained on the top of an inverted cylinder within the cast-iron column, into which cylinder air is admitted (through a valve opened by the workman) from the furnace blast, the air passincr up the tube seen m the axis of f. The inverted air-cylinder is 8 J feet in diameter? 36 feet long, and rises 25 feet; being made air-tight with water, it ascends in its columnar case which IS 4 feet in diameter, without friction. Tlie space, o h. Jig. 1309, is 36 feet The iron cone, which serves as a valve to the charging-drum or cylinder, is raised and lowered by means of a chain passing round a worm-wheel, which is turned round by an endless screw, acted upon by the long rod at c, which the workman can move bv hand at pleasure, thereby lowering or raising the end of the short lever d to which the valve cone is suspended. The cord by which the workman opens or shuts the air piston-valve is seen at «, / I have viewed with much pleasure the precise and easv movements of this feed-apparatus, at an excellent blast furnace in Codner Park iron works. SMOKE PREVENTION. Among the fifty several inventions which have been patented for ell ecting this purpose, with regard to steam-boiler and other lar^-e furnaces very few are sufficiently economical or effective. The first person who investigated this subject m a truly philosophical manner was Mr. Charles Wye WUliams, managing director of the Dublin and Liverpool Steam Navigation company, and he also has had the merit of constructing many furnaces both for marine and land steam-engines, which thoroughly prevent the production of smoke, with increased energy of combustion, and a more or less considerable saving of fuel, according to the care of the stoker. The specific inven- tion, for which he obtained a patent in 1840, consists in the introduction of a proper quantity of atmospheric air to the bridges and flame-beds of the furnaces, througha great number of small orifices, connected with a common pipe or canal, whose aitacan be increased or diminished, according as the circumstances of complete combustion mar require, by means of an external valve. The operation of air thus entering in smaU jets into the half-burned hydro-carburetted gases over the fires, and in the first flue, is their perfect oxygenation, the development of all the heat which that can produce, and £® ^^^11^ prevention of smoke. One of the many ingenious methods in which Mr. Williams has carried out the principle of what he justly calls his Argand furnace. la represented in ;Jg. 1310, where a is the ash-pit of a steam boiler furnace; b, is the c • • • •- . • •••••# • • • •- • • » • • • • • mouth of a tube which admits the externa! air into the chamber or iron box of distri- buuon, c, placed immediately beyond the fire-bridge, g, and before the diffusion or 664 SOAP. S^era'^Tht/in I'^^Z^^T.^J,^^^^^^ -'t^er with round or oblon, which may have its fire-brick lin^g alL perforat^ 1^ ^^' ^^^' '^^ '' '^' ^''-^^^^ )ects in front, and it, as well as the sidw andaTh^H** ^" f^P^^ /ases, the fire-door pro- of perforated fire-tiles, enclosed in common bS^^rk^^^ ^'''''"^^' ^^^ ^^"^tnicted which the air may be admitted in Te^n]atldZsnih.\^T ^"^^^"^ediate space, into X^^if e^Sc£^^^^ t^rsSter '^ -^-^"^ • of the house of cimrns of t^eTue^^^^^^^^^^ fnnlTr" ^^ S?°H^ ^'^^^^^i^'* <^ommitt«i Uoa to many furnaces of the largest S^^^ f ^r- Wmiam^,^ p,^,^^ j„^^„. worth, of Manchester, who, mountini^n the fii^sfSf,!. '^^"'^"^ ^y ^'' HenryHoulas- jn an external dial index, succeeded In observi^^ ^Z^^"''^^''^'^!^ ''^> ^^ich act^ duced by varying the introduction of he aiHe s Infn ,7 ^"^*^^*>» oftemperature, pro- out of the furnace. He thereby demons rati that 20 T' "^^^"''^^ ^^«« P«««i«8 easily obtained from the fuel when Mr wni: ,^ ?^ ^^^ ^^^^' ^^^^ ^eat could be the fire was left to burn in ^re'usu'^rr^rd tf^^^r^' "^^^^^^ volumes of smoke. It is to be hoped, that a kw win k« ^ P«>duction of the usual parliament for the suppression,or aneast aLtement nf th''^''"^ '° '^"""^* session of disfigures and pollutes many Darts of TnnHnnS?^^^" nuisance, which so greatlv while it acts i^^juriously oV^nTm^l^^nd ve"etX^^^^ '^"^"'^ manufacturing low "s' Williams for his indefatigable and d sLterlstfd 1« w -^ ^Much praise is due to Mr faSoJ/L &nr -'- -' --- o^o^lTyt^^^^^^^ - oilf w^fh te !:-lJtiJ^ Vo^ t\etS::L-T""1'- ^^ -^"^«ed fats or matters, when subjeoeed to the^acUon of alk^lfT "^^^^»^'"g l^nen, ^he olive, butter, are most easily 'saponified. Acco^din/ ^o the n Ir ''' 'fV' *^"^ grease, and SIX or seven days are required to comnCrfhp ro.^»/?'^'^V'^ ^^ ^^^ ^^^^^^ Kingdom, day or two more for settling the imS.es f It .n^f ^^" °^ ^ P"" °^ ^^'^ soap,;nd a of tallow are estimated to VoduJ? one toi of --^ ' '"''•J"* ^'*'"' ^^ ^^ ^ ^^^^ manufactories the tallow usK be ^ai^nmed w1^^^^^ i ^"^" ^^^^^^ ^^^ i" miny soap was converted, in the course of t^e process i Jin \'^ i'^'' *°^ '^^ ''^^^Jt^^? ^ft of muriate of soda, or weak kelp levs in suffip.Vn, ' ? ^^'^ ^^'^P' *>y ^^^ introduction of soda by the reaction of the potSh uno^ tZ n ?'f '? ^"™^^^ the proper quan^Sy potash, and the diminished price Is weU as imnrnv^i'^ 'f '* .^"^ ^« ^4^ prfce of led to their general adoption in soaiS. improved quality of the crude sodas, have tains in general about 36 per cem of rp«1 ^n/ !^*"^'^ "'^^ ^^^ ^^^ soap-boiler con muriate of soda, and more^or fess undecornnniH'" ^^l ^^ateof dry carbonat^, mS with ash, made from sulphate of sodl in whiT^K^'^ sulphate. I have met lately with s^l jnperfectlydecompSsed?af ^^ii^ai^'r^^^^^^^^ J-- - '" woJkrd^a^S"^- TenSl"'''V- T ^"'"«"« to the sciaranulctu^^^^^^^ circumstance equally lenerifl^e contain from 18 to 24 npr /.^.m^r i ? ' ^"^ barillas from Spain and employed in England; l^iHa bein/ suono.Pd'^^^^ '^^' ^^' ^^^^'^ i" both s^a^es^s %P> - ^^^^''''''''''''^-^^om^^^^ '"""' '" ''''' • ^"^' white or cLS ine crude soda of eithpr n«j v • cylindrical cast-iron vats,7roL g to T^^ftet w^Tan'd f '%^ ^^^^^^^^ ^^^^ ^-« « kyer consisting, of course, of unslaked or^hpiiS^^^^^ 4 to 5 feet deep; the lowest perforated with holes, and a lateral tb^lur^^^^^^^ The vats have a false botro^' laug, similar to the S,ine of the Frents^ ""^^^^ i^ t£ 'lin^rtri^LVcrcreB SOAP. 665 mid caustic, arter infiltration through the beds of lime. The quantity of lime must be proportional to the carbonic acid in the soda. Upon 1 ton of tallow put into the soap pan, about 200 gallons of soda ley, of •pecific gravity 1-040, being poured, heat is applied, and after a very gentle ebullition of about 4 hours, the fat will be found to be completely saponified, by the test of the ^atula, trowel, or pallet knife; for the fluid ley will be seen to separate at once upon the steel blade, from the soapy paste. Such leys, if composed of pure caustic soda, would contain 4 per cent, of alkali ; but from the presence of neutro-saline matter, they ■eldom contain so much as 2 per cent. ; in fact, a gallon may be estimated to contain not more than 2 ounces ; so that 200 gallons contain 25 pounds of real soda. The fire being withdrawn from the soap pan, the mass is allowed to cool during one hour, or a little more, after which the spent leys, which are not at all alkaline, are run off by a spigot below, or pumped off above, by a pump set into the pan. A second similar charge of ley is now introduced into the pan, and a similar boiling process is renewed. Three such boils may be given in the course of one day's work, by an active soap-maker. Next day the same routine is resumed with somewhat stronger leys, and so progressively, till, towards the sixth day, the ley may have the density of M60, and will be found to contain 6 per cent, of real 8oda.» Were the ley a solution of pure caustic soda, it would contain at this density no less than 14f per cent, of alkali. The neutro-saline matter present in the spent l»y is essential to the proper granulation and separation of the saponaceous compound ; for otherwise the watery menstruum would dilute end even liquefy the soap. Supposintr 12J cwts. of tallow to yield upon an average 20 cwts. of hard soap, then 20 cwts. of tallow will produce 32 cwts. ; and as its average contents in soda are 6 per cent., these 32 cwts. should require 1-52 cwts. of real soda for their production. If barilla at 20 per cent, be the alkaii employed, then 7-6 cwts. of barilla must be consumed in the said process. 11 the alkali be soda-ash of 40 per cent., half the weight will of course suffice. I have reason to believe that there is great waste of alkali incurred in many soap-works, as 6 cwts. 01 soda-ash, of at least 30 per cent., are often expended in making 1 ton of soap, being 50 per cent, more than really enters into the composition of the soap. ^ The barillas always contain a small proportion of potash, to which their peculiar value, in makmgaless brittle or more plastic hard soap than the factitious sodas, may with great probability be ascribed. Chemistry affords many analogies, especially in mineral waters, where salts, apparently incompatible, co-exist in dilute solutions. We may thus conceive how a small quantity of stearate or oleate of potash may resist the decomposing action of the soda salts. The same modification of the consistence of hard soap may. However, be always more conveniently produced by a proper admixture of oleine with stearin e. Soda which contains sulphurets is preferred for making the mottled or marbled soap, whereas the desulphureted soda makes the best white curd soap. Mottling is usually given in the London soap-works, by introducing into the neariy finished soap in the pan a certain quantity of the strong ley of crude soda, throush the rose spout of a waterinj-can. The dense sulphureted liquor, in descending through the pasty mass, causes the marbled appearance. In France a small quantity of solution of sulphate ot iron is added during the boiling of the soap, or rather with the first service of the leys. The alkali seizes the acid of the sulphate, and sets the protoxyde of iron free, to mingle with the paste, to absorb more or less oxygen, and to produce thereby a variety of tints. A portion of oxyde combines also with the stearine to form a meta he soap. When the oxyde passes into the red state, it Rives the tint called maiUeau Isabelk. As soon as the mottl^r has broken the paste, and made it pervious in all directions, he ceases to push his rake from right to left, but only plunges it perpendiculariy, till he reaches the ley; then he raises it suddenly in a vertical line, making it act like the stroke of a piston in a pump, whereby he lifts some of the ley, and spreads it over the surface ol the paste. In its subsequent descent through the numerous fissures and chan- nels, on Its way to the bottom of the pan, the colored ley impregnates the soapy particles in various forms and degrees, whence a varied marblin? results"^ Three pounds of olive oil afford five pounds of marbled Marseilles soap of good qua- lity, and only four pounds four ounces of white soap; showin- that more water is retained by the former than the latter. Oils of grains, as linseed and rapeseed, do not afford so solid a soda soap as oil of olives; but tallow affords a still harder soap with soda Some of the best Windsor soap made in London contains one part of olive oU (callipoli) for every nine parts of tallow. Much of the English hard soap is made with kitchen and bone fat, of a very coarse quality ; the washing of the numerous successive leys, however, purifies the foul fats, and deprives them of their offensive smell in a great decree. It is common now at Marseilles to mix ten per cent, of the oil of grains with olive oil ; for which purpose a large proportion of the oils extracted from seeds • According to my own ezperimenta upon the soda ley used in the London s(«p-works. »!•. I 666 SOAP. washing ; because Che t.o^p«i« of ft/?Ise to .mllX"'"" """^ '"'' ""*' *■" temperature, and letTcoolTo he^^i„, ii„r .r °!f ' '*."°" " "'e '""«' I^s^iWe •nenon to be due toSfcalStracHon r„ , . "f '!.T-"?'."^«' P™"'"? "-e pheno-' risen from 54» to 140» P^ attraction. In some trials of this kind, the themomeler hat When four pans of cSi™ nil »~ V.vJ. „-.k * '""" """i*' ""^ ''"^"J^ " <■""» '0° to 1 1'. is now the^eLral pracfe arCl^s .rn^:'°^'"-P''^'"'*'°^ linseed oil, m tTTd^;i^^r;^;;^ersi4tatv^^^^^^^ leys should not be caustic .arextr^ord?n«rt I .-"^^P '" ^"^"'^ ^^^^^^^ "^^ that the fairly established, to™t?^u"rthe "t'o'ngtty '"° ''"' '"'' '"'" '"^ ^PonihcaUo. i. in.^:h^rsn::haT;irLTat"i^^^ SrelTa LtSr5J:„^r!^;?o^ n"crS«' ^"/-Ufe'ptii'SrcTri water directly. ^ * ^*'* ^ '^ "^^^ ^^^ '^«'«'- ^^t, because it receives the . 144 pounds of o°l viTld « M.'rJ^nl! ^'"* """ "'™"«'' "' '^ "■™™ upon No. I. poundsof soap™ IM S'^uS;onri"68*" ^Tf' ""'?"' "■"" '"'•o" ^^0 to 244 this rate nearly'eo ponnd^oJoU «e consle^ ' " ""' '" ""^"^ '»« J"""-^ "^^J'' « . OF YELLOW OR ROSIN SOAP. of?^Sg\ransSji*^.rin''!.dd" a'dtmnTofr' " ""' ""T"" susceptible, lilce fa... itself The more caustctSe alMrt2e7lcl[^^^^^^^^^^^ IS made with it. Hence fat of 3p Wi„!l i„ . j v, * ""* resinous compound which with the rosin, themZ,ultl^rA^ru'^i?y^^'?^'''"'^\"'r ^ ""^ "'»»« As alkaline matter cannot be nSi^S by^;i„ ?. '^Zl" "^f " '^T/™"' **'"« S"""- «o«p poor in fat, and is r^irto »m .!i L^ r' ,. P'^««"'<» 'ts peculiar acrimony in a fibres So which it is appM^^R fe sad^afrZla ^i"'"'' '"^""' ""'' "" »"'«'• »"'"»» of rosin in soap moJ? than an^^'a t'^olr^t i^l „7 ftY'Tromwh '^ ^T^*^" said, It IS obviously needlpcs tn moL-^ .k^ ,^o- ** j^'/^ "^ ^^'- irom what we have just io., therefore, is fir.tr31^rLrtfer:lSXTnl^^uUtS;r^^ SOAP. 667 service or chaise of ley, namely, when this ceases to be absorbed, and presenres in the boiling-pan its entire causticity, to add the proportion of rosin intended for the soap. In order to facilitate the solution of the rosin in the soap, it should be reduced to coarse powder, and well incorporated by stirring with the rake. The proportion of rosin is usually from one third to one fourth the weight of the tallow. The boil must be kept up for some time with an excess of caustic ley; and when the paste is found, on cooling m sample of i^ to acquire a solid consistence, and when diffused in a little water, not to leave a resinous varnish on the skin, we may consider the soap to be finished. We next proceed to draw off the superfluous leys, and to purify the paste. For this purpose, a quantity of leys at 80° B. being poured in, the mass is heated, worked well with a rake, then allowed to settle, and drained of its leys. A second service of leys, at 4° B., is now introduced, and finally one at 2°; after each of which, there is the usual agitation and period of repose. The pan being now skimmed, and the scum re- moved for another operation, the soap is laded off by hand-pails into its frame-moulds. A little palm oil is usually employed in the manufacture of yellow soap, in order to correct the flavor of the rosin, and brighten the color. This soap, when well made, ought to be of a fine wax-yellow hue, be transparent upon the edges of the bars, dissolve readily in water, and afford, even with hard pump-^ater, an excellent lather. The frame-moulds for hard soap are composed of strong wooden bars, made into the form of a parallelogram, which are piled over each other, and bound togelher by screwed iron rods, that pass down through them. A square well is thus formed, which in large soap lactories is sometimes 10 feet deep, and capable of containing a ccuple of tons of soap. Mr. Sheridan some time since obtained a patent for combining silicate of soda witk hard soap, by triturating them together in the hot and pasty state with a crutch in •n iron pan. In this way from 10 to 30 per cent, of the silicate may be introduced. Such soap possesses very powerful detergent qualities, but it is apt to feel hard and be •omewhat gritty in use. The silicated soda is prepared by boiling ground flints in « •trong caustic ley, till the specific gravity of the compound rises to nearly double the density of water. It then contains about 35 grains of silica, and 46 of soda-hydrate, u 100 grains.* Hard soap, after remaining two days in the frames, is at first divided horizontally into parallel tablets, 3 or 4 inches thick, by a brass wire ; and these tablets are again cut vertically into oblong nearly square bars, called wedges in Scotland. The soap-pans used in the United Kingdom are made of cast iron, and in three sepa- rate pieces joined together by iron-rust cement. The following is their general form : — The two upper frusta of cones are called curbs ; the third, or undermost, is the pan, to which alone the heat is applied, and which, if it gets cracked in the course of boiling, may easily be lifted up within the conical pieces, by attaching chains or cords for raising it, without disturbing the masonry, in which the curbs are firmly set. The surface of the hemispherical pan at the bottom, is in general about one tenth part of the surface of the conical sides. The white ordinary tallow soap of the London manufacturers, called curd soap, con- eists, by my experiments, of — fat, 62 ; soda, 6 ; water, 42 ; = 100. Nine tenths of the fat, at least, is tallow. I have examined several other soaps, and have found their composition somewhat different. The foreign Castile soap of the apothe- A perfumer's white soap was found to cary has a specific gravity of 1'0705, and consists of — Soda ... Oily fat - - - Water and coloring-matter 100-0 English imitation of Castile soap, spec, grav. 0-9669, consists of— Soda - - - - 10-5 Pasty consistenced fat - - 75-2 Water, with a little coloring- - matter ... 14*3 100-0 A perfumer's white consist of — soap was found Soda . - 9 Fatty matter Water - - - 76 . 16 100 Glasgow white soap- Soda . . 6*4 Tallow - . - 600 Water - - - 33-6 lOO-O e By my own experiments upon the Uquld silicate made at Mr. Gibbs's excellent soap tetoqr. 668 Glasgow brown rosin soap^. Soda - . . Fat and rosin Water SOAP. 100*0 A London cocoa-D'it oil soap was found to consist of— *"uau Soda - , ^ - coc„.„u, ,aM : : 2,: • - 73*5 A poppy-nut-oil of— Soda OU Water 100-0 ^lli''*^''!"^'"^.^^^^ ^°*P ^«8 sufficiently •olid ; but It dissolved in hot water w th Zl'""' ^r^'^'l- It is called marine slap, because it washes linen with sea water. hard soap consisted - 7 - 76 - 17 _ 100 rhe soap known in France by the name of soap tn tables, consists, according to M. Thenard's analysis, of— ^ Soda - . . 4.g Fatty matter . . 50.2 Water . . . ^^.^ JOO-0 M. D'Arcet states the analysis of M«iu seilles soap at— Soda - - - fi Water - - - 34 loo SOFT SOAP. quantity of it, and become solid • th^v Tr« T ■ ^ T .. * ^® ^°"°^^ ^^^^^ » large .;.h.eblerWiveXa^lV^^^^^^ mcKlerate consist'ence. This feeble7l:sW;^o^^^^^^^^^ ^^^fj' P«^*^^ «-P of if there be a small excess of the alkali Tt iJthlt^r ? ^ to deliquesce, especially the leys ; and the washing or r'Lg^^^^^^^ '^ ^^P^-'ate it frsm ble in the soft. Perhans howpvpr tific P^^^^^'^f °? *^« hard-soap process, is inadmis&J effected by usingTensr'leys of m^^^^^^^ or abstraction of water mi^ht be wda change the pS intraso^aTan Iv '^^^^^^^ Those of muriate or sulphate of solubility, more aUcaline reactlonT^nriower pd^^^ ^7^ ^'' ""P^rior purposes, and especially for scoudng wX y'arnl^d 1 '^7' " '"'^""* '^^ ""^^ Soft soaps are usually made in this country with whalp Jp«1 «r j r . and a cerla n quantity of tallow • on thp nnnL l .u .' ^^*'' °^^^^' »"<^ Imseed oUs, rapeseed, linseed, poppy-sej?, a„VcoLa^^^^^^^^^^^ ^^' ""' "^ ^^°^P««^d' ^^^same^ tallow is added, ;s^nGrea7 Britain, th^ ob7ecf ^To nr^H ''T"/ "^ ^^^^^ o"^' ^hen grains of stearic soap in the transparent mass call S ^fi^ '^ l^'^^ ^"^ somewhat solid •embles the granular texture of a fi| ^^""^^ ^'^'^ ^^^^ ^*P ^^^"^ ^^ The potash leys should be made perfectlv can«t.\. o«,i r . , strengths ; the weakest being of speci^c eravitv iT ' a .u^ *' ^^^'' ^^° ^^^^^^n* 1-25. Being made from the potasres of comlrcf th^K *^^ ^^^^^^^^t' ^'20, or even 60 per cent., and often less, of real alkali th^ lev.' T. '^ '^1'^- " '^^'^""^ "'^'^^ ^^^^ double their alkaline strength tha\ 's '^saJ a Jola^^^^^^^ '" specific gravity to density, would be fully twice as strong THp fXn ^^r^^^."^ of pure potash, of the same .pectable manufacturers of sol IZ^lsaJor^eTT^ '' '^" F'""'^'' ^°"°^«J ^y re. upon the continent. ^ ^ " *"'^'' ^"^'"^ naturally or artificially green) A portion of the oil being poured into the pan, and heated ir^ n«o 1 .u u •,• of water, a certain quantity of the weaker lev k fntrJ !^ ^? ^^T^^ *^^ ^o»'*"S P«'nt as to bring the mixfure to a boiUngstate Then .n '''^' *^^ ^'^ being kept up so jernately, till the whole quanUty of oLin^^^^^^^ *"^. ley are added al- lilion is kept up in the gentlest manner oossiblP IJ ^^'^ *' introduced. The ebul- ndded, till the workman'judgel trs^ponEuirto^be"?^^^^^^^^^^^ progressively less tumultuous, the frothy mass sub^irL .k^ ♦ ^^^ ^^''"'^ becomes it gradually thickens. The operatin is considered fn hi fi P^f ^.^T' transparent, and to affect the tongue with an acrid plgenc/t^^^^^ IntM^""^"^ ""^'^ '^^ ^^''^ ^'^'^ •nd when a little of the soap placed to coo7 ur^n 1 *" '^*"^f *"d opacity disappear, consistency. ^ ^ '*'*^ "P""* * ?lass plate, assumes the proper A peculiar phenomenon may beremarkpd in «}»o/.«^i- 1.. , « of the quality of the soap. wLn iSe^rformed .Z '^"fl^^i ''? *^^"^' * ^^"^ *^"^^"on . fraction of an inch broaJ, this is up 'Ud "o In^^ the htlle patch, an opaque zone, caUed the */ren^f A; when it is absent lhr«n»n-f^ *'°"'P'^'^ saponification, and 1^ .one soon vanifheJ after be ng disSt y seen thf 1'" T "^J^^ ''r^''' ^'^^'^ '"^^ When it occurs in the best ^U the 1^ TV^rLTa^^^^^^^^^^^^ SOAP. 669 by removing the fire, and then adding some good soap of a previous round, to cool it down^ and prevent further change by evaporation. 200 pounds of oil require for their saponification — 72 pounds of American potash of moderate quality, in leys at 15® B. ; and the product is 460 pounds of well-boiled soap. If hempseed oil have not been employed, the soap will have a yellow color, instead of the green, so much in request on the continent. This tint is then given by the ad- dition of a little indigo. This dye-stuff is reduced to fine powder, and boiled for some hours in a considerable quantity of water, till the stick with which the water is stirred presents, on withdrawing it, a gilded pellicle over its whole surface. The indigo paste dififused through the liquid, is now ready to be incorporated with the soap in the pan, before it stiffens by cooling. M. Thenard states the composition of soft soap at — potash 9-5, 4- oil 44*0, 4- water 46-5, = 100. Good soft soap of London manufacture, yielded to me — potash 8*5, -{- oil and tallow 45, -j- water 46*5. Belgian soft or green soap afforded me — potash 7, -(- oil 36, -|- water 57, = 100. Scotch soft soap, being analyzed, gave me — potash 8, -j- oil and tallow 47, -j- water 45w Another well-made soap — potash 9, -f- oil and fat 34, -j- water 57. A rapeseed-oil soft soap, from Scotland, consisted of — potash 10, + oil 51-66, -4- water 38-33. An olive-oil (gallipoli) soft soap, from ditto, contained — potash with a good deal of carbonic acid 10, oil 48, water 42, = 100. A semi-hard soap, from Verviers, for fulling woollen cloth, called savon economiqut, consisted of, potash 11-5, -{- fat (solid) 62, -|- water 26-5, = 100. The following is a common process, in Scotland, by which good soft soap is made :— 273 gallons of whale or cod oil, and 4 cwts. of tallow, are put into the soap-pan, witu 250 gallons of ley from American potash, of such alkaline strength that 1 gallon con- tains 6600 grains of real potash. Heat being applied to the bottom pan, the mixture froths up very much as it approaches the boiling temperature, but is prevented from boiling over by being beat down on the surface, within the iron curb or crib which sur* mounts the caldron. Should it soon subside into a doughy-looking paste, we may infer that the ley has been too strong. Its proper appearance is that of a thin glue. We « should now introduce about 42 gallons of a stronger ley, equivalent to 8700 gr. of pot- ash per gallon ; and after a short interval, an additional 42 gallons ; and thus suc- cessively till nearly 600 such gallons have been added in the whole. After suitable boil- ing to saponify the fats, the proper quality of soap will be obtained, amounting in quan- tity to 100 firkins of 64 pounds each, from the above quantity of materials. It is generally supposed, and I believe it to be true, from my own numerous experi- ments upon the subject, that it is a more difficult and delicate operation to make a fine •oft soap of glassy transparency, interspersed with the figged granulations of stearate of potash, than to make hard soap of any kind. Soft soap is made in Belgium as follows :— For a boil of 18 or 20 tons, of 100 kilo- ^ammes each, there is employed for the leys — 1500 pounds of American potashes, and 600 to 600 pounds of quicklime. The ley is prepared cold in cisterns of hewn stone, of which there are usually five in « range. The first contains the materials nearly exhausted of their alkali ; and the last the potash in its entire state. The ley run off from the first, is transferred into the se- cond ; that of the second into the third ; and so on to the fifth. In conducting the empatage of the soap, they put into the pan, on the eve of the boil- ing-day, 6 aimes (1 ohm, = 30 gallons imperial) of oil of colza, in summer, but a mixture of that oil with linseed oil in winter, along with 2 aimes of potash ley at 13° B., and leave the mixture without heat during eight hours. After applying the fire, they con- tinue to boil gently till the materials cease to swell up with the heat ; after which, ley of 16° or 17® must be introduced successively, in quantities off of an aime after another, till from 2 to 4 aimes be used. The boil is finished by pouring some ley of 20° B., so that the whole quantity may amount to 9| aimes. It is considered that the operation will be successful, if from the time of kindling the fire till the finish of the boil, only five hours elapse. In order to prevent the soap from boiling over, a wheel is kept revolving in the pan. The operative considers the soap to be finished, when it can no longer be drawn out into threads between the finger and thumb. He determines if it contains an excess of alkali, by taking a sample out daring the boil, which he puts into a tin dish ; where if ,it gets covered with a skin, he pours fresh oil into the pan, and continues the boil till the soap be perfect. No wonder the Belgian soap is bad, amid such groping in the dark, without one ray of science ! SOFT TOILET SOAPS. The soft fancy toilet soaps are divisible into two classes : 1. good potash soap, colored and scented in various ways, forms the basis of the Naples and other ordinary soft 8o«p« i 'i ■f!l 670 SOAP. of the perfbmer; 2. pearl soapy (savon nacrcy') which differs from the other both in phy^ leal aspect and in mode of preparation. Ordinary soft Toilet Soap. — Its manufactare being conducted on the principles already ' laid down, presents no difficulty to a man of ordinary skill and experience ; the only point to be strictly attended to, is the degree of evaporation, so as to obtain soap always of uniform consistence. The fat generally preferred is good hog's lard j of which thirty pounds are to be mixed with forty-five pounds of a caustic ley marking IT* on Baume*8 scale; the temperature is to be gradually raised to ebullition, but the boil must not be kept up too long or too briskly, till after the empatage or saponification is completed, and the whole of the ley intimately combined with the fatty particles; after this, the evapora- tion of the water may be pushed pretty quickly, by a steady boil, till copious vapors cease to rise. This criterion is observed when the paste has become too stiff to be stirred free- ly. The soap should have a dazzling snowy whiteness, provided the lard has been well refined, by being previously triturated in a mortar, melted by a steam heat, and then strained. The lard soap so prepared, is semi-solid, and preserves always the same ap- pearance. If the paste is not sufficiently boiled, however, it will show the circumstance very soon ; for in a few days the soap will become gluey and stringy, like a tenacious mass of birdlime. This defect may not only be easily avoided, but easily remedied, by subjecting the paste to an adequate evaporation. Such soaps are in great request for shaving, and are most convenient in use, especially for travellers. Hence their sale has become very considerable. Pearl soft Soap. — It is only a few years since the process for making this elegant soap became known in France. It differs little from the preceding, and owes its beautiful aspect merely to minute manipulations, about to be described. Weigh out 20 pounds of purified hog's lard on the one hand, and 10 pounds of potash ley at 36* B. on the other. Put the lard into a porcelain capsule, gently heated upon a sand-bath, stirring ^ constantly with a wooden spatula; and when it is half melted, and has a milky appearance, pour into it only one half of the ley, still stirring, and keeping up the same temperature, with as little variation as possible. While the saponification advances gradually, we shall perceive, after an hour, some fat floating on the surface, like a film of oil, and at the same time the soapy granulations falling to the bottom. We must then add the second portion of the lev; whereon the granulations immediately disappeai and the paste is formed. After conducting this operation during four hours, the past* becomes so stiff and compact, that it cannot be stirred ; and must then be lightly beaten. At this time the capsule must be transferred from the sand-bath into a basin of warm water, and allowed to cool very slowly. The soap, though completely made, has yet no pearly appearance. This physical property is developed only by pounding it strongly in a marble mortar ; whereby all its particles, which seemed previously separated, combine to form a homogeneous paste. The perfume given to it, is always essence of bitter almonds ; on which account the soap is called almond creartiy crcme d*amandes. HARD SOATS FOR THE TOILET. The soaps prepared for the perfumer, are distinguished into different species, according to the fat which forms their basis. Thus there is soap of tallow, of hog's Iturd, of oil of olives, of almonds, and palm oil. It is from the combination of these different sorts, mingled in various proportions, and perfumed agreeably to the taste of the consumer, that we owe the vast number of toilet soaps sold under so many fantastic names. One sort is rarely scented by itself, as a mix- ture of several is generally preferred; in which respect every perfumer has his peculiar secret. Some toilet soaps, however, require the employment of one kind more than of another. Formerly the Windsor soap was made in France, wholly with mutton suet ; and it was accordingly of inferior value. Now, by mixing son^ olive oil or lard with the suet, a vei7 good Windsor soap is produced. I have already stated, that the fat of the London Windsor is, nine parts of good ox tallow, and one of olive oil. A soap made entirely with oil and soda, does not afford so good a lather as when it contains a considerable proportion of tallow. The soaps made with palm oil are much used ; when well made, they are of excellent quality, and ought to enter largely into all the colored sorts. They naturally possess the odor of violets. The soaps made with oil of almonds are very beautiful, and preserve the agreeable smell of their perfume ; but being expensive, are introduced sparingly into the mixtures by most manufacturers. Some perfumers are in the habit of making what may be called extempore soaps, em- ploying leys at 36P Baume in their formation. This method, however, ought never to be adopted by any person who prefers quality to beauty of appearance. Such soap is, indeed, admirably white, glistening, contains no more water than is necessary to its con* SOAP. 671 Btltntion, and may therefore be sold the day after it is made. But it has counter-Daian- cing disadvantages. It becomes soon very hard, is difficultly soluble in water, and, if not made with tallow, does not lather well. Hog's lard is very commonly used for ma- king that soap. Twenty kilogrammes of the fat are taken, to ten kilogrammes of soda lej', at 36° B. (specific gravity 1-324) ; as soon as the former is nearly fluid, five kilo- grammes of the ley are introduced, and the mixture is continually agitated during an hour with a wooden spatula. The temperature should never be raised above 150° Fahr. at the commencement of the operation ; at the end of one hour, five other kilogrammes of ley are to be added, with careful regulation of the heat. The paste thus formed by the onion of the fat and alkali, ought to be perfectly homogeneous, and should increase in consistence every hour, till it tecomes firm enough to be poured into the frame ; during wklch transfer, the essential oils destined to scent it, should be introduced. Next day the soap is hard enough; nor does it differ in appearance from ordinary soap, only it requires prompt manipulation to be cut into bars and cakes ; for when neglected a day or two, it may become too brittle for that purpose, and too hard to take the impression of the stamps in relief. Such an article gets the name of little-pan soap, on account of the small quantity in which it is usually manufactured. Hard soap, made in the com- mon way, is, on the contrary, called large-pan soap. This extemporaneous compound is now seldom or never made by respectable manufacturers. In making Windsor soap, the admixture of olive oil is advantageous ; because, being richer in oleine than suet, it sa- ponifies less readily than it, and thus favors the formation of a more perfect neutral com- bination. When the soap cuts, or parts from the ley, when the paste becomes clotty, or. In the language of the operative, when the grain makes its appearance, the fire should be immediately withdrawn, that the impurities may be allowed to subside. This part of the operation lasts twelve hours at least ; after which, the soap, still hot, becomes alto- gether fluid and perfectly neutral. For every 1000 pounds of the paste, there must be introduced nine pounds of essences, mingled in the following proportions: — six pounds of essence of carui ; one and a half ditto lavender, (finest) ; one and a half ditto rosemary. The mixture must be well stirred, in order to get completely saturated with the perfumes; and this may be readily done without at all touching or stirring up the subjacent leys ; m the course of two hours, the soap may be transferred into the ordinary frames. In twenty-four hours, the mass is usually solidified enough for cutting into bars and cakes, ready to be stamped for sale. The above method of scenting Windsor soap is practised only in the largest establish- ments ; in the smaller, the soap is pailed out of the soap-pans, into a pan provided with a steam case or jacket, and there mixed with the essential oils, by means of appropriate beat and agitation. The most fashionable toilet soaps are, the rose, the bouquety the cinnamon, the orange- flower, the musk, and the bitter almond or peach blossom. Soap d la rose. — This is made of the following ingredients : 30 pounds of olive-oil soap ; 20 of good tallow soap. Toilet soaps must be reduced to thin shavings, by zr/eans of a plane, with its undei face turned up, so that the bars may be slid along it. These shavings must be put into an unlinned copper pan, which is ^rrounded by a water-bath, or steam. If the soap be old and hard, 5 pounds of water must be added to them ; but it is preferable to take fresh-made soaps, which may melt without addition, as soap some time kept does not readily form a homogeneous paste. The fusion is commonly completed in an hour, or thereby, the heat being applied at 212° F., to accelerate the progress, and prevent the dissolution of the constituent water of the soap. For this purpose the interior pan may be covered. Whenever the mass is sufficiently liquefied, 1| ounces of finely groiad ver- milion are to be introduced, and thoroughly mixed, after which the heal may be taken off the pan ; when the following perfumes may be added with due trituration :— 3 ounces of essence of rose ; 1 ditto cloves ; J ditto cinnamon ; 2| ditto bergamot ; = 7f . The scented soap being put into ihe frames, speedily consolidates. Some recommend to pass the finished fused soap through a tammy cloth, in order to free it from all clots and impurities ; a very proper precaution in the act of transferring it to the frame. If the preceding instructions be observed, we obtain a soap perfect in ever)' point of view; possessing a delicious fragrance, equally rich and agreeable, a beautiful roseate hue, and the softest detergent qualities, which keeping cannot impair. Such a soap has, in fact, been known to retain every property in perfection during four or five years. When the essential oils are particularly volatile, they should not be added to the soap till its tem- perature has fallen to about 140° Fahr. ; but in this case a more careful trituration is required. The economy is, however, ill bestowed ; for the cakes made of such cooler soap are never so homogeneous and glossy. ^ Soap au bouquet. — 30 pounds of good tallow soap ; 4 ounces of essence of bergamot ; oil of cloves, sassafras, and thyme, 1 ounce each ; neroli, | ounce. The color is given with 7 ounces of brown ochre. 672 SOAP. SOAP. 673 Cinnamon Soap. — 30 ponnds of good tallow soap ; 20 ditto of palm-oil soap. Per fumes: — 7 ounces of eseence of cinnamon; 1| ditto sassafras; jj ditto bcrgamot. Color : — 1 pound of yellow ochre. Orange-jlofwer Soap. — 30 pounds of good tallow soap ; 20 ditto palm-oil soap. Per ftimes :— 7| ounces essence of Portugal ; 7^ ditto amber. Color : — 9i ounces, consisting of 8J of a yellow-green pigment, and Ij of red lead. Mtisk Soap. — 30 pounds of good tallow soap ; 20 ditto palm-oil soap. Perfumes : Powder of cloves, of pale roses, gilliflower, each 4h ounces ; essence of bergamot, and essence of musk, each 3h ounces. Color : — 4 ounces of brown ochre, or Spanish brown. Bitter Almxmd Soap — Is made by compounding, with 60 pounds of the best white soap, 10 ounces of the essence ol bitter almonds. LIGHT SOAPS. The apparatus employed for making these soaps is a copper pan, heated by a wateN bath ; in the bottom of the pan there is a step, to receive the lower end of a vertical shaft, to which arms or paddles are attached, for producing constant agitation, by causing them to revolve among the liquefied mass. Inio a pan so mounted, 50 pounds of good oil soap of any kind are put (for a tallow soap does not become frothy enough), and melted by proper heat, with the addition of 3 or 4 pounds of water. By the rapid rotation of the machine, an abundant thick lather is produced, beginning first at the bottom, and creep- ing gradually upwards to the top of the pan, when the operation should be stopped ; the soap having by this time doubled its volume. It must now be pailed off into the frame, allowed to cool, and then cut into cakes. Such soap is exceedingly pleasant at the wash- stand, feeling very soft upon the skin, affording a copious thick lather, and dissolving with the greatest ease. TRANSPARENT SOAPS. These soaps were for a long time manufactured only in England, where the process was kept a profound secret. They are now made every where. Equal parts of tallow soap, made perfectly dry, and spirit of wine, are to be put into a copper still, which is plunged in a water-bath, and furnished with its capital and refrigeratory. The heat applied to effect the solution should be as slight as possible, to avoid evaporating too much of the alcohol. The solution being effected, must be suf- fered to settle ; and after a few hours* repose, the clear supernatant liquid is drawn off into tin frames, of the form desired for the cakes of soap. These bars do not acquire their proper degree of transparency till after a few weeks' exposure to dry air. They are now planed, and subjected to the proper mechanical treatment for making cakes of any form. The soap is colored with strong alcoholic solution of archil for the rose tint, and of turmeric for the deep yellow. Transparent soaps, however pleasing to the eye. are always of indifferent quality ; they are never so detergent as ordinary soaps, ana they eventually acquire a disagreeable smell. Tlie exports of soap from this country during the last 9 months, (November 1862), wen 117,623 cwt. against 99,983 cwt. in 1851, and 96,123 in 1850. The following is an invention for which Dr. Normandy obtained a patent. When yellow soap is made with the cheaper kinds of fat, tt will hardly acquire a sufficient degree of firmness or hardness to satisfy the thrifty washerwoman. It melts away too rapidly in hot water ; a defect which may be well remedied by the introduction into the soap of a little fused sulphate of soda ; and the salt concreting gives the soap a desirable hardness, while it improves its colour, and renders it a more economical article for the washing-tub. In a trial recently before the Court of Common Pleas, it was proved that the soap made according to Dr. Normandy's patent was worth fully 21. a ton more than the original soap, without the sulphate of soda. Soda-ash is the substance employed in the manufacture of soap, and varies in the amount of soda it contains to the extent of from S§ to 50 per cent, according to the mode of its formation. A small quantity of this soda is occasionally in the caustic state ; but the great bulk is combined with carbonic acid, as carbonarte of soda, and variable proportions of chloride of sodium and sulphate of soda exist with it in the soda ash. The fabrication of soap is under the surveillance of the excise, and conse- quently there is little or no scope for improvement, — an assertion well supported by the notorious fact, that no alteration baa taken place in it since the reign of Queen Anne. Yet, looking upon the innumerable changes and metamorphoses which the fats and oils are capable of undergoing through the agency of chemistry, there is no subject which offers a- fairer field for the labours of inventive genius than this very manufacture. The elements united together in the class of animal and vegetable oils of fats are not numerous, but seemingly fitted for displaying an endless mutability ; and no doubt the day- will come, when, from perhaps the cheapest and most worthless of these substances, we shall be able to form every other variety, or, even from wood and coal extract substances of this kind to rival and supersede tallow, wax, or spermaceti. At present, however, tlie i. prmcipal manufacturer mterested in the working out of such questions lies under the inquisitorial power of our great fiscal harpy. Improvement under such an influence loses Its reward; for concealment is impossible, not only for the period required to seal a patent, but even for a day or an hour. The excise officer is omnipotent in a soap work, for he carries the master key of every lock on the premises : all must open wheh he knocks : all must explain when he questions. In spite, therefore, of the thousands ^.nf-T.r^ discoveries which have been made within the last twenty years in depart- S!" ^;^ ^'^ ""r^^^ *"'^^.*** soap-making, this manufacture has stood still for more SjrH^^.r^"' ? ^'^'^"*' 9"^ "^""'^ remarkable proofs of the unwholesome and im- S^ M t« ir ap-™aker like the water bubbling in down hi r J I r "'*^ ?\^"^ r""°^ ^"J^^' *^^ V^^^^re^ boon, for he is tied hZ »f Th !"TaP'^'''?^'^ ^"^ 5?""^ ^'''' necessary for the social status of this kinff- nZfll hi r ^"T ^T: ^"I '!r'^' "P^" *^« ^»P n^anufiicture will con^ quently bear no proportion whatever to the importance of the subject or to the position wS LTV ^''"T *«Tr^''^ 'f^""'^ /'"™ ^^^'- restrictions: the L:un which has so ong restrained the wmg of invention would laugh at our efforts to raise the victim of his oppression. ^ "*'** In this department of industry, improvement has therefore, of necessity a foreiffn origin and hence we regard it as a mere matter of course that the Exhibition pr^ ?nl„ iV.wV T f fr P^'"^ ':i^" *^^ ^^"?' ^^ ^° American. Mr. John Ransom St John, of New \ ork, for the soap made under whose process a prize medal has been most justly awarded, has, we see, secured his process in this country by letters patent vet .t will not surprise us m the least to find that Mr. St. John is prevented brtheexcbe from fol owing out h.s invention here. A circumstance exactly parallel to this assunintTon occurred a few years ago to another foreigner, Dr. Normandy, who had taken oui patent for improvements m soap-making, but was ruinously in erfered with and u Iti mately stopped by the excise. In wishing Mr. St John, therefore, all tie sucSe^ hb extremely mgenious invention merits, we warn him that he may yet fal b^nSth ttie cnishmg influence of the Broad Street authorities ^ ^ neneatn the viously spoken of is mixe^d with an amSunroTVe^lntTy^lTeXe U^^^^^^^^^^ previously ascertained strength of the soda-ash; with^these a c^rtaTnTulHf s^^^^^^^ generally mixed, for the purpose of facilitating the subsequent process of fili^tl^ The entire mixture is now placed, layer by layer in a tank !imil^r t^^K . 5 -u ",' for lixiviating the ball-soda'^n soda iorkl X^ayers of ^ L- ^rJ^JlX layers of rush-matting from each other, and a plu- l^inc. driven into f»fa^!fwl •« ^ of the tank this lattef is filled full of wkter an/alfo^d to s"an3 frtwelve oT eiZt"^ hours. The plug be ng then withdrawn, the saturated solution of cTustL sodTflows down into a reservoir placed beneath; after which, the plug is again replS mZl water applied, and this operation is repeated five or six times"; the fariou" iSsThu* obtained being conveyed into separate reservoirs, and distinguished from eac2 other by ^e names first running, second running, and so on, the last lling of course tte wSesf When weak soda-ash is employed little or no common salt need be addpd f n Thfr^' ture m the lime vat; but when soda-ash of great stren-th is used it i, np.if f ^^i a considerable quantity of common salt to it for a DurnosP whtl^ '' "^^1^,7 *« ^^ plained. Having in this way produced a series of cSc Ivis of dTi 'Y."^ ^ ^^Z strength, the weakest is pumped up into a b^i er cop^^asT^^^ ^T'' ""^ ally made of cast-iron. To this lye a quantity of tallow^««?^oi 5 .i '^' ^^^^J' .^^"^'- some time, or until, upon testing it tTeTe is fonnZn ifi^ i' ^"l*^^ ""^^^ ^'^^^ *"«' The whole is now klloVed to ccSl and remain aUest untU tLT' ''" '*!J''^"- n^/"^' alkali, settles to the bottom of the copper whence ft i. n Ln!J^^%"r ^t^'T^ 2^ '^ pump, as the excise regulations do noTpermitTto t wS^i^^^^^ "^. ^^""^ other countries, from the bottom' of the boiler Thf, fl„^f ^T "" ?^1 ^ *' ** ^^ and contains a portion of glycerine derived from ThL f^f \ ^f"«°""ated spent lye. flulphate and muViate of soda of he soda-ash and In .HWr ' *f^^«^' *?g«*^«»' ^^th the soda added by the soap-maker. Sie presence of hi *^,^'.*7*1 q"^"*' y of muriate of for otherwise the taUow and lye wouTd Se L o 1 ^nf^^^^^ "^^ « mdispensable, would be impossible afterwards^toleparate he Slnt Ive h.^ T^^''^"' ^T ^.t'"^^* soluble in a solution of common salt the partialinlnJff^^^ '°*5 •' '']^'^^^^^^ '^^ to float on the surface, and permits of th^e^Slv?nrl?^^ I*'"' ^•■°"^*^* whence as we have seen it ia n.Tna^ « spent lye precipitating to the bottom, fron» wn^ce, as we nave seen, it is pumped away and lost, being of no value mive. at wbicU the grease u'said to^.^ "4^^»"^f roThTloXfie UlCt 4« «74 SOAP. •aponified, or combined with ite full equivalent ot soda. This point is well known to the workmen by the consjstence of the compound, when a little of it is squeezed between the finger and thumb and allowed to cool; if finished, it readily separates from the skin as a hard cake and, moreover, has no longer the taste peculiar to grease ; if, on the con- trary, any ^^l^/^^J^'" . ^^«*P<>f »fied, this oozes out by the pressure, and becomes perceptible both to the sight and taste. A more certain mode, however, is to decom- pose a portion of the suspected soap by means of an acid, and ascertain whether the resultnig grease is wholly soluble in boihng spirits of wine, for, if not, the saponification has been imperfect. Presummg, however, that a perfect result has been secured, the soap has now to be brought into a marketable condition, and, for this purposeTit is fused with a quantity of weak lye or water. So soon as combination lias takeVplkce a quantity of very strong lye is added, until an incipient separation begins to show itself The heat is now increased, and the boiling continued for a considerable time the mass being prevented from boiling out of the vessel by workmen, armed with shovels who dash the soap to and fro, so as to break the froth upon the surface, and fkvour evapomtion. At first the soap is divided into an innumerable number of small globules each separate and distinct from its fellow; but, as the boiling goes on, those graduallv' run together into larger and larger globules, till at last the soap is seen to assume a pasty consistence, and to unite in one uniform mass, through which the steam from below slowly forces its way in a series of bursts or little explosions. The process is now tmished and all that remains to be done is to shut down the Ud of the copper, havintr previously extmguished the fire. In from one to two or three days, accordincr to the nature and quantity of the soap in question, the lid is again raised, and tire semifluid soap ladled from the precipitated lye by means of ladles; the product being thrown into a wooden or iron frame, of specific dimensions, where its weight is estimated by measurement, and the duty charged upon it. In making common yellow or resin soap, the resm is usually added after the saponification of the tallow, in the proportion of on4- third or one-fourth of the tallow employed. The subsequent operations are much about the same as those above described ; but, in addition, just before closing the lid of ^e copper, a quantity of water or weak lye is sprinkled over the melted soap, which carries down with it the mechanical impurities of the resin ; and these constitute a dark layer of soap restmg upon the lye, which is not poured into the frame with the rest, but 18 placed apart under the name " nigerr and brings a less price. Good curd or white soap should cont^n of or « w >»*"»« Orease Soda Water or consist of Grease acid Soda Water - - 61*0 parts 6-2 " - 32-8 •* 100 1 atom=816 1 atom= 32 17 atom8=153 Resin soap has a more variable composiUon, but, when not adulterated with water •nould contain about as follows : — Grease and resin Soda Water 60 84 100 ^e manufacture of soft soap differs greatly from that of hard soap; as, in this case Snd 3'' ^'P"' T^ ^'•^'^ t^^™''^^"--? i« tl^e boiler; and the alkali employed is IS] and not soda. The mode of obtaining a caustic lye of potash is exActfy the simc as with soda, except that the weak lyes are used in place of water for V subTequeSJ operation, and not pumped up into the boiler. The materials employed as fats a?e mixturesofthe vegetable and animal oils, as rape, and the fish-oil ^lled "Southern " For the best kinds of soft soap, a little tallow is added to these, which prXces a S^n ft' Thlf T^'^'1^ ^^ crystallization in the soap, that conf;rs add itfonal value upon It. These oils or fats are merely boiled with the strong caustic potash-lye, until thorough combination has taken place, and so much of the watir of the lye is evaporated, that, when a portion of the soap is poured upon a cold slab, and allowed to rekt for a few mmutes, it assumes the consistence of soft butter. As soon as this happens, the whole is run out into little casks, where it cools; and is thus sent into the market. Of course no atomic arrangement can be traced in so variable a compound; and hence iU SOAP. 675 mni^fnJ'I^nrr "W'"a*'C'"'***'^'*- ^^ employment of soft soap is daily becoming more and more bmited. Soft soap usually contains as under ^ Fatty oils - - . . - 48 Potash - . . . - 10 Water - . . . - 47 bat its composition differs greatly. fatfv 3V^i W^^'^i^iir^t PTr'^ '° ^ P?*^"* &'^°*«^ »» 1845 to make soap from wSe otl arc nuf fnl^^"'^^^^ ™'*"' of sulphuric acid. 10 tons of palm oil or wnaie oil are put into a wrought-iron vessel provided with a perforated steam worm- through which steam is admitted till the temperature rises to 350^ F the ili^Z^^r ¥he tanr?i.'s?st\*""'-'""'^ of brick lined with lead and sunkt the^^ou"d Ihe tank has a steam pipe inserted into it, and has a wooden cover lined with lead, having two manholes in it. It is closed by an oil joint about 8 inches deen Thro^h the c^ver a pme passes connected with a high shaft for the escape of offensWe vaSs and their concfensation by a jet of cold water. 2000 lbs. of sulfuric acifof 18 s^E^^^^ gravity are poured into the tank ; the temoerature of the mas^s b^rng meaLwhili^^ fully watched hj a thermometer and not allowed to exceed SSO^ pihl TTe admis^c^ of steam IS continued wh.le the acid is being slowly poured in. When this is do"e thS fire IS extinguished But steam is admitted for 4 hmiVs afterwards King heated btwy by passing through pipes placed over a ^re. The steam being stopped, and the mai somewhat cooled, a large pump is introduced, and the product is^ turned out into^ wooden vessel lined with lead and provided with a steam worm. In thrveLlthe f^ttv Tpn l/' T^"* by n^eans of free steam with half its bulk of water f^ 2 h^irs an^^^^^ then allowed to rest for 12 hours. The product thus obtained can be made into Un b the ordinary way ; but it is better to distil it first See Fat ^ *r«X'^o^T-^'^'i"'^ ''^'^'''^^'f ^ our E^ise LarcH.-ln 1831, the candle makine trade was, after a long reign of oppression, emancipated from the odious exc^ hTrpies^ and, says the patno ic Mr. G. F. Wilson, "those only know their crai^pfng inflTen« who have worked under them. Our neighbour trade, soap making, sho^'^^ts in?urv b^ he fiict that the German soap makers are so far in advance of oufi thai theVbiy from cha rs^'tile En"Lh «t^^ '"'1; '" ^^'V^^l V^^ freight, commission^aid^the" cnarges. while English soap makers cannot use it, though at their own doors. Tn HerpTh^TP ^^'•^f^^ol^^^cid forms a part of llmost every ste^icTndtfectory Here the nuisance of being subject to fixed times and rules of work, and to prvinriJ' cisemen m most cases prevents the business."- On ^A. Stearic CalkMLu}J^reLG ^iS^' ^c^?;\^ZT'^J^''''^^''^ ^fP^^^^'^ Candle Company. 1852. ^ ^ SOAPS QUALITY OF. To determine the quantity of water, thin slices are cut from the edges and from the centre of the bars. A portion is then weig^^^^^^^ 6 grammes (60 o 70 gmins), and exposed to a curre^of air heated t^ 212-' Fahr or k J^if bath^^ntil It ceases to lose weight Tlie dry substance is then weLhed X difference between che first and last weighing will indicate the quantity of wafer e;a^ rated If it be a soft soap, it is weighed in a counterpoised shallow ^psuTeln^ ^Xll ;"rrnt.°' "^'^'' ^"^^^ ''•^'^ '' "- '' P- -'^' - -ottled anTsoft'oa';^ gS^ The purity of soap may be ascertained by treating it with hot alcohol- if the soan b« wh e and without admixture, the portion Remaining undissolved is verV m^nte aL a mottle soap of good quality does not leave, when oLratinHn 5 ^aLZs Z^'thnn S centigrammes, or about 1 per cent i^i«tiiig ou o grammes, more than 5 If there should be a sensible amount of residue from white soap, or more than 1 n*.r cent from mottled soap, some accidental or fraudulent admixtur^e may b^ su^ecSi ^^naTyst""'' '''^*"^' *"'*'^ ^"^"^^^^ ^"^ ^^^^ ^' ^^^^ m"7be''d:Sfned alkdLt"'^'^ '^ '^^'^^ '''*"^"^^ ^° '^' ««*P ^« ^^y d-^-^^i^ed by means of the 10 grammes in thin slices are taken, for instance, and dissolved in 150 grammes of boiling water •, and this solut on is saturated with a normal M^.Z^ !.^J- e^*°**°^® of of water 100 grammes of sulphuric JtdXecTiTsl^Tv^^^^^ *° f' ^T' Tl. volume of this l^uor^equired fo~lft""^^^^^ T^r^lrZte I'f'X'"''' ^^^ ^'^^' '' ''''^' ^^^^ ^^^^^^ ^o ^i^^ulS wTigh^ The quantity^ pure potash or soda may be thus deduced. There is no difficulty m ascertaining in the same assay the quantity of the fatty sub- stance. For this purpose 10 grammes of pure white wax free from water are adJed to hiT-l • ^1!" '^%'^''^:^ r'^ sulphuric acid, and the whole heated to completrHque faction : it is then allowed to cool, and when it has become solid, the cake of wlx ^^d 676 SODA. fatty matter -which have united is removed, and "washed, dried and weighed ; the augmentation in weight beyond the 10 grammes employed will give the weight of the fatty matter. The liquid decanted from the solidified wax may afterwards be tested, to ascertain the purity of the base. The solution of the sulphate may also be evaporated, and, by an examination of ita crystalline form, or by means of chloride of platinum, it may be ascertained whether the base be soda or potash, or a mixture of the two. As to the nature of the fatty substance, it is ascertained with more or less certainty, by saturating the solution of the soap with tartaric acid, collecting the fat acids, and taking their point of fusioa It is possible, at least, by this to prove the identity or the absence of identity with the sample in the soap supplied ; for instance, whether it is made from oil or tallow, is an alkaline sub StEQce, used in chemical researches, in bleachine, and in the manufacture of soap. It i^ prepared by boiling a solution of crystallized carbonate of soda in 4 or 5 parts of water, with half its weight of recently slaked and sifted lime. At the end of half an hour, the Tessel of iron, porcelain, or preferably silver, may be removed from the fire, and covered carefully, till the calcareous matter has settled into a solid magma at the bottom. The clear supernatant ley may be then decanted into bottles for use in the liquid state, or evaporated, out of contact of air, till it assumes an oily appearance, then poured upon an iron or marble slab, broken into pieces, and put up in vials secured with greased stop- pers or corks. Caustic soda is a white brittle mass, of a fibrous texture, a specific gravity of 1*536, melting at a heat under redness, having a most corrosive taste and action upon animal matters, dissolving readily in both water and alcohol, attracting carbonic acid when exposed to the atmosphere, but hardly any water, and falling thereby into an eflaorescent carbonate ; it forms soaps with tallow, oils, wax, rosin ; dissolves wool, hair, silk, horn, alumina, silica, sulphur, and some metallic sulphurets. It consists of 77*66 soda, and 22*34 water. A solution of caustic soda affords no precipitate with solution of chloride of platinum, or tartaric acid, as a solution of caustic potash never fails to do. The following Table of the quantity of Caustic Soda contained in Leys of different densities, has been given by Richter : — 1 Spec. Soda Spec. Soda Spec. Soda Spec. Soda grav. per ceut. grav. per cent. grav. per cent. giav. per cent. 1*00 0-00 1*12 11-10 1*22 20*66 1*32 29*96 1*02 2-07 1*14 12*81 1*24 22*58 1-34 31*67 1«04 4*02 1*]6 14*73 1*26 24*47 1*35 32*40 1-06 6*89 M8 16*73 1*28 26*33 1-36 33-08 1*08 7*69 1-20 18-71 1*30 28*16 1*38 34*41 MO 9-43 Soda free from water can be obtained only by the combustion of sodium, which see. On the 30th of June, 1838, Messrs. Dyars and Hemmings obtained a patent for manufacturing soda by the decomposition of sea-salt with sesquicarbt^nate or bicarbonate of ammonia. Equal parts of the chloride of sodium and sesquicarbonate are pres- cribed, being very nearly the equivalent decomposing proportions, and the ammonia salt is recommended to be added in powder to a saturated solution of the sea salt, and the mixture to be stirred, and then set aside till the mutual action and decomposition be effected. Having been employed to examine this process for a gentleman who wished to adopt it on a manufacturing scale, I obtained tlic following results. On SODA. 677 ^r -r making the prescribed mixture in the cold, brisk effervescence takes place, because the quantitv of carbonic acid combined with the ammonia is greater than the resulting soda can readily absorb, even to form its bicarbonate, and this extrication of gas carries off with it more or less ammonia, amounting, in carefully conducted experiments, to no less than 27 per cent, of the sesqui-carbonate employed ; though the magma deposited from the mixture was drained in vessels nearly close, and though the ammonia which adhered to it, as well as that in the drained mother liquors, was recovered by distilla* tion in vessels connected with aWoulfe's apparatus. Moreover, the utmost amount of soda-ash (not pure carbonate) which was obtained, was only 37*5 for 100 of sea salt used, whereas 90 of carbonate should result from 100 of the sea salt, with the above equivalent dose of sesqui-carbonate of ammonia. This latter salt contains about one ^ half more carbonic acid than is required by the soda to become a carbonate. A good illustration of the loss of ammonia in a similar case is afforded by the decomposition of chloride of calcium in solution, by adding to it the equivalent dose of pulverized ammonia carbonate ; viz., 56 of the former and 59 of the latter. The rapid extrication of the carbonic acid on making this mixture, causes such a waste of ammonia, that more of the sesqui-carbonate must be afterward introduced, to complete the decompo- sition of the chloride ; the stronger the solution of the chloride the greater is the loss of ammonia. In one of my experiments where were employed 3500 grains =half a pound avoir dupois, of each ingredient, the following were the products : — 1. Ammonia recovered by distillation from the drained magma, equivalent in sesqui-carbonate to - - - - - 2. Ammonia as carbonate, from the remaining liquid, sucked into a vacuous apparatus and distilled - - - - - 3. Additional ammonia as carbonate, obtained from the cold mother liquors, by distillation with quicklime, and out of the sal ammoniac formed -------- Grains. 257 1509 Sesqui carbonate employed 775 2541 3500 4 Loss .... - 959 or 27-4 per cent. The product from this experiment in dry soda ash was only 1500 grains, which were found to contain only 1312 of pure carbonate, or 87*6 per cent, of the whole. Here is a deficiency of soda carbonate, upon the quantity of the chloride used, of no less than 68^ per cent, for only 1312 grains are obtained instead of 3150. Subsequently a method occurred to me, whereby this process, elegant in a scientific point of view, might possibly be executed with advantage upon the commercial scale ; out it would require a very peculiar apparatus, though not nearly so costly as what was erected by Mr. Cooper, under the direction of the patentees, at Battersea and in Brussels. SODA, CARBONATE OF {Kohlemaures natron^ Germ.) ; is the soda of commerce in various states, either crystallized, in lumps, or in a crude powder called soda-ash. It exists in small quantities in certain mineral waters ; as, for example, in those of Seltzer, Seydschutz, Carlsbad, and the volcanic springs of Iceland, especially the Geyser ; it fre- quently occurs as an efflorescence in slender needles upon damp walls, being produced by the action of the lime upon the sea salt present in the mortar. The mineral soda is the sesquicarbonate, to be afterwards described. Of manufactured soda, the variety most antiently known is barilla, the incinerated ash of the Sahola soda. This plant is cultivated with great care by the Spaniards, especially in the vicinity of Alicant The seed is sown in light low soils, which are embanked towards the sea shore, and furnished with sluices, for admitting an occasional overflow of salt water. When tlie plants are ripe, the crop is cut down and dried ; the seeds are rubbed out and preserved ; the rest of the plant is burned in rude furnaces, at a temperature just sufficient to cause the ashes to enter into a state of semi-fusion, so as to concrete on cooling into cellular masses moderately compact. The most valuable variety of this article is called sweet barilla. It has a grayish-blue colour, and gets covered with a saline efflorescence when exposed for some time to the air. It is hard and difficult to break ; when applied to the tongue, it excites a pungent alkaline taste. I have analysed many varieties of barilla. Their average quantity of free or alkali- metrical soda is about 17 per cent; though several con tarn only 14 parts in the hundred, and a few upwards of 20. This soda is chiefly a carbonate, with a little Bulphuret and sulphate ; and is mixed with sulphate and muriate of soda, carbonate of lime, vegetable carbon, Ac. 678 SODA. SODA. «rf Another mode of manufacturing crude soda is by burning sea- weed into kelp. For merly very large revenues were derived by the proprietors of the shores of the Scottish islands and Highlands^ from the incineration of sea-weed by their tenants, who usually paid tlieir rents in kelp; but since the tax has been taken off salt, and the manufactur* of a crude soda from it has been generally established, the price of kelp has fallen extremely low. The crystals of soda-carbonate, as well as the soda-ash of British commerce, are now made altogether by the decomposition of sea-salt. SODA MANUFACTURE. The manufacture divides itself into three branches : — 1. The conversion of sea sail or chloride of sodium, into sulphate of soda. 2. The decomposition of this sulphate into crude soda, called black balls by the workmen. 3. The purification of these balls either into a dry while soda-ash or into crystals. ' 1. The preparation of the sulphate of aoda.—Figs. 1311, 1312, 1313, represent the furnace for converting the muriate of soda into the sulphate. The furnace must be built interiorly of the most refractory fire-bricks, such as are used for glasshouses, but of the ordinary brick size ; except the bridges c, g, n, which should be formed of one mass, such as what is called a Welsh lump, a is the ash-pit ; b, the grate ; c the first bridge, between the fire and the first calcining hearth d, d ; f, f, is its roof;' g' the second bridge, between the calcining hearth and the decomposing hearth i, i,* i ; ' the roof of which is k, k. This hearth i, i, is lined with a lead square pan, 5 or 6 inches deep, sloped at the back opening, in fig. 1313, marked m'; which deficient part of the upright side is filled up with two bricks placed one over the other, as shown at m, m fig. 1312, and luted with clay, to confine the semi-liquid mass in the pan, i, i. Some manufacturers make this pan 8 inches deep, and hne its bottom and sides with bricks "^ or silicious sandstone, to protect the lead from the corrosive action of the acid. There are others who consider this precaution troublesome, as the points of the pan which become leaky are thereby concealed. In the roof of the decomposing hearth, one or two syphon funnels r, of lead, are in- serted when the charge of acid (sul- phuric) is to be poured down upon — — ;; s ^^^ ^^'* ^^ '» '» to save the risk of any annoyance from the fumes of the muriatic acid, o, o, is a chimney filled with round flint nodules, which are kept continually moist by the trickling of a streamlet of water upon the topmost layer. The muriatic gas, meeting this descending film of water upon so extensive a surface, becomes absorbed, and runs out below in a liquid form. When the acid is required in a somewhat concentrated state, this chimney should be made both high and capacious. Such a plan, moreover, is very valuable for abating the nuisance caused by the disengagement of the muriatic acid ■^ 1812 M El _ gas; which is otherwise apt to sterilize the surrounding vegetation A fire being kindled in the grate B,figs. 1311. and 1312, 3 cwts. of salt in powder are to be thrown by a shovel into the pan i, through the door M,fig. 1813, or m.m fig 1312. Two hundred weights and a half of oil of vitriol, of specific gravity 1-844 havini been diluted with from 25 to 30 per cent, of water, and well mixed, or 3 cwts. at 56^ Baume, are to be slowly poured in by the funnel, and diffused among the muriate of soda, by an occasional stir with an iron rake cased with sheet lead. Fumes of muriatic acid will now plentifully escape, and, passing up the condensing-shaft o, will flow down .n the form of hquid spirit of salt, and escape by the stoneware stopcock p, mto tlie pipe of a sunk cistern. The fire having been steadily kept up at a moderate degree, the chemical reaction wdl be tolerably complete in the course of two hours ; but as this is relative to the nature of the fuel, and the draught of the furnace, no very precise rule in point of time can be laid down ; but it is sufficient for this stage of the process when the fumes cease to be very dense and copious, as may be ascertained by opening the door M, and looking in, or by the appearance at the lop of the shaft o. Over the door m' in the opposite side of the decomposing hearth, /ig. 1313, there must be an arch or hood terminating in a small chimney, 15 or 20 feet high, for the ascent of the muriatic vapors. '' i 1313 O l .'fr ,5| , , , , ^P 1.5 . . -f'tajo 1314 when the charge Is drawn or mn out of the hearth, and allowed to fall into a «innre shallow iron tray, placed on the ground at the back of the furnace, /or this discharge, the two bricks which serve as stoppers to that orifice, must be unluted and r^emovea. As soon as that charge is taken out, (the fire being meanwhile checked by opening the door T,fig. 1312, and shutting partially the ash-pit opening at a,) a Iresh charge must be introduced as above described. The nearly decomposed saline matter, during the second charging of the hearth i, will have grown cool and concrete. It must be shovelled into the calcining hearth d, D.fig. 1311, by the back door Q,;ig. 1813, where it will receive a higher degree of heat; and, by the expulsion of the remaining part ot the muriatic acid, it will become a perfect sulphate of soda. It should be finally brought into a state of semi- fusion. When a sample of it, taken out on \he end of the rake or trowel- shaped scraper, emits no fumes, the con- version is accomplished. From 3 cwts. of common salt, or mu- , , 1 , 1^1 I V T'| o riate of soda, rather more than 3i cwts. of perfect sulphate should be obtained, quite free Uvm metallic impurity. The next step is the conversion of the sulphate into a crude soda. One of the most improved soda furnaces is that employed in a few factories, repre- sented in figf. 1314, 1316, and 1316. In the section fig. 1315, there are two hearths in one furnace, the one elevated above the level of the other by the thickness of a brick, or about 3 inches, a is the preparatory shelf, where the mixture to be decomposed is first laid in order to be thoroughly heated, so that when transferred to the lower or decomposing hearth b, it may not essentially chill it, and throw back the operation. c is the fire-bridge, and d is the grate. In the horizontal section, or ground plan, /ig. 1316, we see an opening in the front corresponding to each hearth. This is a door, as shown in the side view or elevation of the furnace, fig. 1314; and each door is shut by an iron square frame filled with a fire-tile or bricks, and suspended by a chain over a pulley fixed in any convenient place. See Pitcoal, COKING OF, p. 1047. The workman, on pushing up the door lightly, makes it rise, because there is a coun- terweight at the other end of each chain, which balances the weight of the frame and bricks. In the ground plan, only one smoke-flue is shown; and this construction is preferred by many manufacturers ; bat others choose to have two flues, one from each shoulder, as at a, 6 ; which two flues afterwards unite in one vertical chimney, from 25 to 40 feet high ; because the draught of a soda-furnace must be very sharp. Having sufliciently explained the construction of this improved fur- nace, I shall now proceed to describe the mode of makin? soda with it. I xi: L III I ^ £ESE I 1 I L J L *■*> ^^t. The materials with which the sulphate is decomposed into a rough carbonate of soda, are chalk or ground limestone, and ground coal or charcoal. The proportions in which these three substances are mixed, influence in a remarkable degree the success of the dfccomposing process. I have known a lalse proportion introauced, and persevered in, at a factory, with the most prejudicial effect to the product; the soda-ash produced being in a small quantity relatively to the sulphate employed, and being much charged with sulphur. After very numerous trials which I have made on the great scale, anu many in(|uiries at the most successful soda-woi-ks, both in this country and abroad, I am war- ranted to offer the following pro|)ortions as the most profitable : — Sulphate of soda, 100 parts; carbonate of lime (chalk or limestone), from 110 to 120 parts; if pure, 110; if a little impure or ilanip, 120; pitcoal, 50 oarts. li I 1 680 SODA. These materials must be separately ground by an edge-stone mill, and siAed into • tolerably fine powder. They must be then very carefully mixed. Attention to these par- ticulars is of no little importance to the success of the soda process. One hundred parts or pounds of sulphate of soda are equivalent to 75 parts of car- bonate, and when skilfully decomposed, will generally yield fully 70 pounds. A charge for the decomposing; furnace with the preparatory shelf should not exceed 200 lbs. or perhaps 180 ; therefore if 75 pounds of ground sulphate of soda, with 80 pounds of chalk or limestone (ground), and 37 pounds of ground coal, be well mixed, they will constitute one charge. This charge must be shovelled in upon the hearth a, or shelf of preparation (fig. 1031) ; and whenever it has become hot (the furnace having been previously brought to bright ignition), it is to be transferred to the decomposing hearth or laboratory b by - an iron tool, shaped exactly like an oar, called the spreader. This tool has the flattened part from 2 to 3 feet long, and the round part, for laying hold of and working by, from 6 to 7 feet long. Two other tools are used ; one, a rake, bent down like a garden hoe at the end ; and another, a small shovel, consisting of a long iron rod terminated with a piece of iron plate, about 6 inches long, 4 broad, sharpened and tipped with steel, for cleaning the bottom of the hearth from adhering cakes or crusts. Whenever the charge is shoved by the sliding motion of the oar down upon the working hearth, a fresh charge should be thrown into the preparation shelf, and evenly spread over its surface. The hot and partially carbonized charge being also evenly spread upon the hearth b, is to be left untouched for about ten minutes, during which time it becomes ignited, and begins to fuse upon the surface. A view may be taken of it through a peep-hole in the door, which should be shut immediately, in order to prevent the^reduction of the temperature. When the mass is seen to be in a state of incipient fusion, the workman takes the oar and turns it over breadth by breadth in regular layers, till h- has reversed the position of the whole mass, placing on the surface the particles which were formerly in contact with the hearth. Having done this, he immediately shuts the door, and lets the whole get another decomposing heat. After five or six minutes, jets of flame begin to issue from various parts of the pasty-consistenced mass. Now is the time to incoi^ rate the materials together, turning and spreading by the oar, gathering them together by the rake, and then distributing them on the reverse part of the hearth; that is, the oar should transfer to the part next the fire-bridge the portion of the mass lying next the shelf, and vice versa. The dexterous management of this transposition characterizes a good soda-furnacer. A little practice and instruction will render this operation easy to a robust clever workman. After this transposition, incorporation, and spreadins, the door may be shut again for a few minutes, to raise the heat for the finishing off. Lastly, the rake must be dexterously employed to mix, shift, spread, and incorporate. The jets, called candles, are very numerous, and bright at first ; and whenever they begin to fade the mass must be raked out into cast-iron moulds, placed under the door of the labonu tory to receive the ignited paste. One batch being thus worked off, the other, which has lain undisturbed on the shelt IS to be shoved down from a to b, and spread equally upon it, in order to be treated as above described. A third batch is then to be placed on the shelf. The article thus ootained should contain at least 22 per cent, of real soda, equivalent to 37 per cent, of dry carbonate, or to 100 of crystals. A skilful workman can turn out a batch in from three quarters of an hour to an hour, producing a perfect carbonate, which yields on solution an almost colorless liquid, nearly destitute of sulphur, and con- taining hard}}' any decomposed sulphate. In some soda-works, where the decomposing furnace is very large, and is charged with a ton of materials at a time, it takes two men to work it, and from five to six hours to complete a batch. Having superintended the operation of the above-described small fur- nace, and examined its products, I feel warranted to recommend its adoption. The followiDET materials and products show the average state of this soda process — Materials.— m parts of sulphate of soda, ground, equivalent to 75 of carbonate; 1 10 of chalk or ground limestone ; 55 of ground coal ; in the whole, 265. Products.— \6S parts of crude soda, at 33 per cent. = 55-5 of dry carbonate. Or, J ^?!? "■ crystals of carbonate of soda = 48 of dry carbonate ; aiii! ' ^100 — msoluble matter. But these products necessarily vary with the skill of the workman. In anotner manufactory the following proportions are used :— Six stones, of 14 lbs, each, of dry ground sulphate of soda, are mixed with 3 of chalk and 3 of coal. This noixtnre, weighing U cwt., forms a batch, which is spread upon the preparation shelf of the furnace (figs. 1037 and 1038), as above described, and gradually heated to inci- picLt Ignition. It is then swept forwards to the lower area b, ly the iron oar, and spread evenly by the rake. Whenever it begins to soften under the rising heat of the SODA 681 laboratory (the side doors being meanwhile shut), the mnss must be laboriously turned over and incorporated ; the small shovel, or paddle, being employed to Iransler, by tne interchange of small portions at a time, in rapid but orderly succession, the whole mate- rials from the colder to the hotter, and from the hotter to the colder pw-ts of the hearin. The process of working one batch takes about an hour, during the first hall ol wbicn period it remains upon the preparation shelf. The average weight of the finished baU is 1 cwt., and its contents in alkalimelrical soda are 33 pounds. , Where the acidulous sulphate of iron from pyrites may be had at a cheap rate, " Has been long ago employed, as at Hurlett in Scotland, instead of sulphuric acid, for decom- posing the chloride of sodium. Mr. Turner's process of preparing soda, by decomposing sea salt with litharge and quicklime, has been long abandoned, the resulting patent yel- low, or sub-chloride of lead, having a very limited sale. ^, , , „ 2. The extraciimi of pure soda from the crude article.— The black balls must be broken into fragments, and thrown into large square iron cisterns, furnished with false bottoms of wooden spars; when the cisterns are nearly full of these lum^ water is pumped in upon them, till they are all covered. After a few days, the lixivialion is effected, and the ley is drawn off either by a syphon or by a plug-hole near the bottom of the cistern, and run into evaporating vessels. These may be of two kinds. The surface-evaporating furnace, shown in fig. 1317, is a very admirable invention for economizing vessels, lime, and fuel. The grate a, and fireplace, are separated from the evaporating laboratory d, by a double fire-bridge b, c, having an interstitial space in the middle, to arrest the communication of a melting or ig- niting heat towards the lead-lined cistern d. This cistern may be 8, 10, or 20 feet long, according to the magnitude of the soda-work, and 4 feet or more wide. Its depth should be about 4 feet. It consists of sheet lead, of about 6 pounds weight to the square foot, and it is lined with one layer of bricks, set in Roman or hydraulic cement, both along the bottom and up the sides and ends. The lead comes up to the top of c, and the liquor, or ley, may be filled in to nearly that height. Things being thus arranged, a tire is kindled upon the grate A ; the flame and hot air sweep along the surface of the liquor, raise its temperature there rapidly to the boiling point, and carry ofl' the watery parts in vapor up the chimney e, which should be 15 or 20 feet high, to command a good draught. But, indeed, it will be most economical to build one high capacious chimney stalk, as is now done at Glasgow, Manchester, and Newcastle, and to lead the flues of the several furnaces above described into it. In this evaporating furnace the heavier and stronger ley goes to the bottom, as well as the impurities, where they remain undisturbed. Whenever the liquor has attained to the density of 1-3, or thereby, it is pumped up into evaporating cast-iron pans, of a flattened somewhat hemi- spherical shape, and evaporated to dryness while being diligently stirred with an iron rake and iron scraper. This alkali gets partially carbonated by the above surface-evaporating furnace, and is an excellent article. When pure carbonate is wanted, that dry mass mu»t be mixed with its own bulk of ground coal, sawdust, or charcoal, and thrown into a reverberatory furnace, like^g. 1316, but with the sole all upon one level. Here it must be exposed to a heat not exceeding 650O or 700° F. ; that is, a little above the melting heat of lead ; the only object being to volatilize the sulphur present in the mass, and carbonate the alkali. Now, it has been found, that if the heat be raised to distinct redness, the sulphur will not go off, but wiU continue in intimate union with the soda. This process is called calking, and the fur- nace is called a calker furnace. It may be six or eight feet long, and four or five feet broad in the hearth, and requires only one door in its side, with a hanging iron frame filled with a fire-tile or bricks, as above described. This carbonating process may be performed upon several cwts. of the impure soda, mixed with sawdust, at a lime. It takes three or four hours to finish the desulphuration ; and it must be carefully turned over by the oar and the rake, in order to bum the coal into carbonic acid, and to present the carbonic acid to the particles of caustic soda diffu- sed through the mass, so that it may combine with them. \Vhen the blue flames cease, and the saline matters become white, in the midst of the 9oaly matter, the batch may be considered as completed. It is raked out, and when cooled, lixiviated in great iron cisterns with false bottoms, covered with mats. The watery solution being drawn off" clear by a plug-hole, is evaiwrated either to dryness, in hemisjherical cast-iron i)ans, as above described, or only to such a strength that it showt 662 SODA a pellicle upon its surface, when it may be run off into crystaUizing cisterns of cast iron, or lead-lined wooden cisterns. The above dry carbonate is the best article for the elast manufJEicture. ** Crystallized carbonate of soda contains 62f per cent, of water. The crystals are colorlesi transparent rhomboids, which readily effloresce in the air, and melt in their own water of crystallization. On decanting the liquid from the fused mass, it is found that one part of the sa t has given up its water of crystallization to another. By evaporation of that fluid, crystals containing one fifth less water than the common carbonate are obtained. These do not effloresce in the air. Mineral soda, the sesquicarbonate {Anderthalb kohlensaures natrm. Germ ) is found m the province of Sukena, in Africa, between Tripoli and Fezzan. It forms a stratum no more than an inch thick, just below the surface of the soil. Its texture is striated crystalline, like fibrous gypsum. Several hundred tons of it are collected annually which are chiefly consumed in Africa. This species of soda does not effloresce like the Egyptian, or the manufactured soda crystals, owing to its peculiar state of composition and density. It was analyzed by Klaproth, under its native name of trcma, and was found to consist, m 100 parts, of— soda, 37 ; carbonic acid, 38 ; sulphate of soda, 25 : water. 22*5, in 100. * This soda is, therefore, composed of— 3 atoms of carbonic acid, associated with 2 atoms of soda, and 4 of water ; while our commercial soda crystals are composed of— 1 atom of carbonic acid, 1 atom of soda, and 10 atoms of water. There are six natron lakes in Egypt. They are situated in a barren valley, called Bahr- bela-ma, about thirty miles to the west of the Delta. There are natron lakes also in Hungary, which afford in summer a white saline efflo- rescent crust of carbonate of soda, mixed with a little sulphate. There are several soda lakes in Mexico, especially to the north of Zacatecas, as also in many other provinces. In Columbia, 48 English miles from Merida, mineral soda is ex. Iracted from the earth in great abundance, under the name of ttrao. Bicarbonate, of soda (Doppelt kohlensaures natrmy Germ.), is prepared, like bicarbonate of potassa,by transmitting carbonic acid gas through a cold saturated solution of pure carbonate of soda, till crystalline crusts be formed. The bicarbonate may also be obtained m four-sided tables grouped together. It has an alkaline taste and reaction upon litmus paper, dissolves in 13 parts of cold water, and is converted by boiling water into the sesquicarbonate, with the disengagement of one fourth of its carbonic acid. It consists of— 37 of soda, 62-35 carbonic acid, and 10-65 water. Soda Manufacture Improved. In carying on this process on the great scale it was long customary to permit the escape of the hydrochloric acid in the decomposition of the muriate of soda by sulphuric acid as a waste product ; and this is done in some localities at the present day. But independently of the actual loss thus caused, the in- jurious action of the acid fumes upon every form of vegetation, for many miles around the manufactory, has compelled the maker of soda to condense this hydrochloric acid, by passing it through flues filled with coke ; over the cavernous surface of which a sraaU stream of water constantly flows. In this way, a large quantity of liquid muriatic acid IS procured, which, though too impure for many of the ordinary requirements of the arta *r^f 1 »?f"ably adapted for the generation of chlorine, and the subsequent manufacture* of chloride of lime. The total worth of this waste product may be gathered from the fact, that in one set of large soda works near Glasgow, sufficient muriatic acid is collected to yield 8,000 tons of chloride of lime per annum, and yet this scarcely represents one- twentieth of the soda manufacture of Great Britain. Having in this way obtained a quantity of sulphate of soda, the soda maker now proceeds to his next operation Here however, it may be as well to remark, that the sulphate of soda in question is not nearly pure, but usually contams from five to ten per cent, of common salt, which has escape'd decomposition in the sulphate furnace ; as it is more economical to leave a small excess of chloride of sodium than to add a superfluity of sulphuric acid,— since this latter is vastly more expensive than the former; and the presence of common salt is rather be- neficial than otherwise during the subsequent process. To convert this impure sulphate of soda into carbonate of soda, it is mixed in about equal proportions with chalk or car- bonate of lime, and small coals, all in a state of rough powder. The mixture, merely thrown togetJier with shovels, is projected into a reverberating furnace called the ball- furnace, where it IS stirred about with a long iron paddle, until it undergoes an imper- feet fusion; and long jets of yellow flame, technically called "candles," burst out from various parts of the mass, which, for an ordinary charge of 3 cwt. or 4 cwt will re- quire about three hours. The whole is then raked out, and allowed to cool, the furnace being supplied, as before, with a fresh charge of materials. The product of this opera- tion IS known as ball-soda, and it consists of carbonate of soda, sulphuret of sodium, chloride of sodium, undecomposed sulphate of soda, carbonate of lime, sulphuret of calcium, and carbon of coke. We have had an opportunity of examining seyeral SODA MANUFACTURE. 683 specimens from the largest manufactories in the kingdom, and find no great difference in the results. The average composition appears to be as under : — Soda Carbonic acid Sulphuret of sodium Chloride of sodium Sulphate of soda Sulphate of calcium Carbonate of lime Coke 19-80 9-24 2-64 6-22 610 29-40 21-70 6-90 100 We shall describe the mode of analyzing this compound a little further on, but at this moment it will be more advantageous to pursue the remainder of the operation for procuring carbonate of soda from the cooled product of the ball-furnace. This substance, under the name ball-soda, is roughly broken to pieces, and piled up in alarge iron tank, provided with a false bottom or grating, and having an aperture near the bottom. When the tank is full, the aperture near the bottom is plugged up, and hot water run upon the ball-soda to within an inch or two of the top of the tank. The whole is allowed to remain for several hours ; by which the salts of soda, consisting, as we have seen, of carbonate and sulphate of soda, with the chloride and sulphuret of sodium, are dissolved ; the plug is then withdrawn, and the soluble matters are allowed to flow away from the carbonate of lime, sulphuret of calcium, and coke, whicli are insoluble. Upon these latter a fresh portion of hot water is poured, so as thoroughly to remove the soda salts ; and this last solution is commonly applied to a quantity of new ball-soda, in order to economize the cost of evaporation. The first fluid from the tank is conducted at once into a reverbera- tory furnace, where the water is rapidly expelled, and a dry saline product obtained. This is immediately transferred to what is called the carbonating furnace, where the sul- phuret of sodium is partly decomposed by the carbonic acid of the furnace, and partly reconverted into sulphate of soda by the oxygen of the air. Meantime, the portion of soda existing in the mass as caustic soda becomes carbonated by the carbonic acid of the fire ; and hence the name of this particular furnace. Having been kept at a dull red heat, but short of that required for actual fusion, the whole is withdrawn and cooled ; after which, it is boiled in water, and the concentrated solu- tion run off into shallow coolers to crystallize. As the saline constituents now consist almost entirely of carbonate of soda, with a little sulphate of soda and chloride of sodium, the former salt crystallizes and becomes solid ; leaving the two latter with a portion of carbonate of soda, in solution. The crystals are taken out, dried, and packed for the market ; whilst the residuary solution is evaporated to dryness, and the result sold under the name of soda-ash : though this name is sometimes also applied to the direct product of the carbonating furnace. The nature of the decomposition which takes 5 lace in the ball-furnace may be very correctly inferred from the composition of the pro- ucts thence ensuing. We have seen that the primary mixture is composed of sulphate of soda, carbonate of lime, and carbon. On exposing these to a red heat, sulphuret of sodium is generated, which immediately acts upon the carbonate of lime, producing sul-'^ phuret of calcium and carbonate of soda. As, however, during the reduction of the sulphate of soda, part of the carbonate of lime is rendered caustic by the expulsion of its carbonic acid, this caustic lime makes its appearance in the ball soda tank, and converts a portion of the carbonate of soda into caustic soda; hence the necessity for the carbonating furnace, which is, moreover, useful in destroying the sulphuret of sodium. We shall now proceed to describe the mode of analyzing ball-soda ; after which it will be necessary to review the whole process of soda-making, with a view to the possibility of improvement. Having selected a fair sample of the ball soda to be examined, this must be reduced to an extremely fine powder, and a given weight of it — stiy 100 grains, digested in two ounces of hot water for ten or fifteen minutes; then throw the whole on a filter, and wash this gradually with 3 ounces of boiling water, taking care to add these washings to the first liquid which passes through the filter. The filter, with its insoluble contents, may now be set in a warm place to dry. Meanwhile, the clear solutions being mixed, are to be tested with finely powdered carbonate of lead, until this ceases to be blackened : when this occurs, the heavy black precipitate of sulphuret of lead is allowed to settle, and the clear colourless solution is poured off iirto a porcelain basin. This being gently heated, is now to be thrown upon the sulphuret of lead ; and, when this has again settled, the clear fluid must be withdrawn and added to that in the porcelain basin. This, being gently heated, must next be treated by a dilute acid of a determinate strength, (stw Aikalimetry), until litmus paper, on being dipped into it, becomes slightly reddened; 684 SODA MANUFACTURE. "whea the amount of soda present, or of carbonate of soda, may be inferred, in the usual way, from the composition of dilute acid. The sulphuret of lead remaining from this operation is now to be supersaturated with acetic acid, and slightly heated, for the pur- pose of removing from it any excess of carbonate of lead that may have been added in the first instance ; the sulphuret of lead must then be well washed with hot water, dried and weighed. Every 120 grains represent 40 grains of sulphuret of sodium, and for this 32 grains of soda must be deducted from the result of the acidulous assay. The m- Boluble matter remaining on the filter is now to be transferred to a double-necked bottle provided with a bent tube, for passing the evolved gases through a solution of the acetate of lead in weak acetic acid. This insoluble matter consists of carbonate of lime, sulphuret of calcium, and coke ; if, therefore, diluted muriatic acid is poured upon it, the two former substances will be decomposed with the evolution of carbonic acid and sulphuretted hydrogen, the latter of which is absorbed by the acidulous solution of the acetate of lead ; whilst the carbonic acid passes on and escapes. In combining with the solution of acetate of lead, the sulphuretted hydrogen gives rise to the formation of sul- phuret of lead, which, being well washed with hot water, then dried and weighed, gives the amount of sulphuret of calcium existing in the residue : for every 1 20 grains of sul- phuret of lead indicates 34 of sulphuret of calcium. The fluid in the two-necked flask consists of chloride of calcium, with the coke of the ball-ash. Tliis must, therefore, be thrown on a filter, and well washed with hot water, and dried : the coke may then be separated and weighed. As from the existence of carbonate of soda in the first solution neither lime nor its sulphate could exist in the insoluble matter, if this had been weighed previously to these latter experiments, the difference in weight, after deducting the sulphuret of calcium and the coke, will be that of the carbonate of lime ; and this, under the circumstances, is suflBciently correct in moderately skilful hands. It now remains, therefore, only to determine the quantity of chloride of sodium and sulphate of soda present in the ball-soda. For this purpose, 100 grains of the finely powdered compound are to be treated exactly as before, with hot water and carbonate of lead. In this case, however, the resulting alkaline solution must be supersaturated with pure nitric acid, and to this an excess of nitrate of silver must be added, and the mixture warmed. A dense coagulated precipitate will fall, from which the clear solution being poured off into a proper vessel, the precipitate is to be washed with a little boiling distilled water, and the washings added to the clear solution before mentioned. The precipitate being now well dried in a dark place must be weighed; and for every 144 grains of this pre cipitate, 60 grains of chloride of sodium must be assumed. To the clear solution result- ing from this operation, an excess of nitrate of baryta must be thrown in, and the mixture slightly heated as before, and then thrown on a previously weighed filter. This filter, when the solution has passed, is to be repeatedly washed with boiling distilled water, until this fluid passes through pure ; the filter is then to be well dried and weighed, to ascertain its increase of weight. This increase is due to the presence of sulphate of baryta, for every 117 grains of which 12 grains of sulphate of soda must have existed in the portion of ball-soda examined. To determine the amount of carbonic acid com- bined with the soda, a given quantity (and for this purpose 50 grains is enough) of the finely-powdered ball-soda must be lixiviated as before, and the clear solution boiled down to dryness with an excess of pure peroxide of manganese, — the whole being at last slightly heated over the fire. By the action of the manganese at this heat, the sulphuret of sodium is converted into sulphate of soda ; and if the soda salts be now dissolved in a small quantity of water, and the solution placed in a proper flask, provided with a bent tube containing chloride of calcium, to arrest moisture, the carbonic acid may be expelled by a known weight of diluted sulphuric acid ; and presuming tlie flask and the vessel containing the dilute acid to have been carefully weighed before and after the experi- ment, the loss gives at once the weight of the carbonic acid united to the soda. This appears never to be equivalent to the amount of soda. There is a circumstance connected with the lixiviation of ball-ash, on the large scale, which has probably escaped the atten- tion of manufacturers, but is of considerable importance towards securing a successful result. The general practice is to employ hot water for dissolving out the soda salts, and to retain this solution in contact with the insoluble residue for several hours. Theo- retically, this is incorrect, and, practically, we have found it injurious. Sulphuret of calcium, though an insoluble salt, is not absolutely so ; and the moment this substance in solution comes in contact with carbonate of soda, double decomposition ensues, attended with the production of carbonate of lime and sulphuret of sodium — a process exactly the reverse of that which happens under the influence of a red heat, and of which, in chemistry, there are many other examples. Thus it constantly happens that sulphuret of sodium is found in the lixiviated products of ball-soda. If, however, cold water be employed, and the contact of the carbonate of soda with the sulphuret of calcium be considerably diminished, as with great ease may be done, by coarsely powdering the ball-soda, instead of employing it in lumos, then the clear solution is almost entirely SODA MANUFACTURE. es§ free from sulphuret or sodium, and is devoid of colour; whereas, by the hot water pit>- Cii^, this fluid is invariably of a dirty-green hue, and has an offensive odour of sulphu- retted hydrogen. Now, remembering that the sulphuret of sodium is a dead loss to the manufacturers, and moreover diminishes the market value of the rest of his produce, the question of hot or cold water, with or without proper pulverization of the ball-soda, is in reality a very important affair. By the afore-recited analysis, it appears that, out of 22-91 parts of soda, 2*11 were combined with sulphuretted hydrogen; this is at the rate of more than 9 per cent., and would form a handsome addition to the usual profits of the manufacturer. One of the great drawbacks upon the manufacture of soda is the difficulty of disposing of the inso- luble residue. This contains more than half its weight of sulphuret of calcium, a sub- stance which, in the wet state, is rapidly decomposed by the carbonic acid of the air with the evolution of sulphuretted hydrogen gas, and, if moderately dry, is almost certain to take fire by contact with the atmosphere, and thus taint the surrounding neighbour- hood with its sulphurous emanations. It is extremely likely that this refuse product would answer the purpose of lime for all agricultural uses, and also furnish sulphur to such crops as require this element, — plants of the natural order cruciferae for example. Gas lime is in great measure a perfectly analogous compound, and this is largely used in some of our inland counties, and found to be an extremely beneficial application. The refuse of soda-works has not, however, assumed a similarly favourable character amongst farmers; and it is now a real and growing nuisance to the manufacturer of Boda. Perhaps, after all, it would be better to think of devising a remedy for preventing the formation of this residuum than seek an outlet for its consumption. With tliis view, we venture to lay the following process before our readers, embracing within itself what may be termed the perfection of soda-making. How far on a large scale the difficul- ties might increase beyond the advantage, our experience will not enable us to judge ; but in a moderate way, the whole of the operations have been consecutively tried and found satisfactory. The key to the ultimate decomposition turns upon a circumstance in chemistry which is, for the most part, but little known : and that is, the ease with which the hydrosulphates of the alkalis, when slightly moistened, are converted into carbonates by the action of carbonic acid. If much water be present, the decomposition goes on languidly, and is never perfect ; if too little water, the decomposition is speedily arrested by the formation of a crust of alkaline carbonate. It is the middle state, between these two conditions, which must be aimed at, and which we will now proceed to describe in a condensed account of the proposed method : — With a precisely similar form of apparatus to that now in use for preparing sulphate of soda, and condensing muriatic acid, but with some little additional care, a given weight of common salt might be converted into sulphate of soda, and the whole of its muriatic condensed, which, of course, would be an exact equivalent of the soda present in the sulphate of soda ; that is to say, 60 parts of chloride of sodium and 49 parts of pure hydrated sulplmric acid would produce 72 parts of dry sulphate of soda, and 37 parts of anhy- drous muriatic acid. These relative proportions must be borne in mind to facilitate the comprehension of the ultimate process. Having placed the muriatic acid on one side for the present, we proceed to conv^t the sulphate of soda into sulphuret of sodium, by mixing it with its own weight of coarsely powdered coal or coke, and exposing the mixture to a red heat in a proper furnace for an hour or two. At this temperature the carbon of the coal unites with the oxygen of the sulphate of soda, and flies off as car- bonic oxide gas, leaving the sulphur and sodium combined together as sulphuret of sodium, with the excess of small coal or coke employed. As soon as this mixture is sufficiently cool, it should be broken or pounded into a rough powder, which must now be moistened with water to the consistence of damp sand, or until a handful tightly squeezed in the hand adheres together as a ball or lump. Wlien this is the case, the whole should be placed in a vessel, or set of vessels, similar to those used for the purifi- cation of coal-gas by means of slaked lime. It is best to have four of these vessels, three of which are to be continually in action. The moistened sulphuret of sodium or hydrosulphate of soda being duly an-anged, a stream of carbonic acid is made to traverse the three vessels in action, by which the hydrosulphate of soda is converted into carbonate of soda, and the hydrosulphuric acid, or sulphuretted hydrogen, being expelled in a pure state, may readily be burnt at a jet in a common sulphuric acid cham- ber, with the usual dose of nitrate of soda for its acidification. Thus the quantity of sulphuric acid originally employed to decompose the salt would be constantly regenerated and used over again. The requisite carbonic acid would also be easily procured by acting upon chalk with the muriatic acid condensed in the first instance. Some fear might seem to be justified by the possibility of the carbonic acid passing off with the sulphuretted hydrogen ; but, under common care, guided by experience, this could never occur. So long as any considerable quantity of hydrosulphate of 686 SODA WATER soda remained in the second and third vesaeb, no carbonic acid could pass throuffh them • and as soon as No. 1 was discoyered to be saturated, this might be tfcrown ou?!f ^0' and the fourth vessel employed; meanwhile No. 1. might be emptied and refiSed w?th ^^luali; '''''"" °" "''" """• '•' ^^'° *'^ ^^^^'^ ^^«^^ ™ luxated ; and rhu. In comniencing this description we assumed at first 60 parts of common salt and 49 of hydrated sulphuric acid, which would give 72 of sulphate of soda 3 87 of muriafic acid Now these 72 of sulphate of soda would form 49 of hydrosulphate of soda wS 37 of muriatic acid by acting upon chalk, would furnish exactly sufficient ir^nir acid to convert the 49 of hydrosulphate of soda into 54 of carbonate of soda^ a^d T 7Tf sul- phuretted hydrogen. But this sulphuretted hydrogen, when carefully consumed woula regenerate 49 parts of sulphuric acid, to be again used in decomposing 60 pa™ s of Zi mon salt, and so on in continual rotation. The only resulting product? wouW therefore be carbonate of soda and muriate of lime; the silphuric acid merely perforS the part of a vehicle for effecting the decomposition. ^As regards the economy of thit process. It seems m no way doubtful ; and, viewed in a practical light, there is no insT mountable or even probable difficulty in the way of ite immediate and successful adop ion: necessarily there would arise some loss from waste and commercial inTpuritfes Zv h! "^T A 'Pf^pl^t^^^ '"^ustry is very large, and all risk of much loss by failun; D ext/ndirlr''^'" reasonable limits by beginning upon a very small scale at firs^ and extending the manufacture m proportion to the success of the enterprise The ?3nTTJ^'°' «^.f "^P^V«* «f. <^^><^i"°i ^^"ch arise under the present system, and con- ^T.aV^^ ^J' ^^^^tj^^'^ pestiferous exhalations, proclaim too obviously that a change {llfK 'a^I^ '°??® 'r^^. ""{ *^^ enormous mass of matter thus daily accumulating may ^rod^cZf f°S;'^'' ^-f' ^^^ °"" soda-maker alone admitted to us that his afer^^ £;nur-:!y.'i^7?;^",;r "' ''^ "'^ ^' ''' ^°^ ^' "•^^^ ^^ '''''' *«- ^' « ??.? Ki"^^^^^' ^® ?® "*°^® ^^^®" *° ^»t" containing a minute quantity of soda and highly charged with carbonic acid gas, whereby it acquires a sparkHng anpeara^e' ILlutZ^LZ^'T'^r'^^^ exhilarating quality, and certain m'l^icina^l powers iJ constitutes a considerable object of manufacture in this kingdom. The followin- fi-ure represents I understand, the best system of apparatus for preparing it. A ven- dilule IlieXi^fdTxXuon!"""^ ^"^^'"^ P"'"^-^^^' - -" beUerstood from' nf Ji'v n^T *PP*™^''« '"fy ^^^^. **»'• "taking any species of aerated water, in imitation IT. iTt 'f""^- ^" ^^^^ i' necessary for this purpose, is to put inti the cistern Q, the neutro-salme matter, earths, metallic oxydes, pure water, &c., each in due pro- Sr'thT'^T '" I^' T^ ".'"'^'^^ *""^>'^'^ «^*^« ^i"«^«l ^«te; to be imitated'^ t^ nfiln.tP h f^lh T '°. '"'^ 'l'"'^ '^". "'"?^^"'"' «' *»>^°^§»» ^^« pipe «» «"d then to \m. Se gasometer F ^^''^' ^ ^""^^ '^' appropriate gas, previously contained in , Thus, to make Seltzer water, for each 12 pounds troy, = 69,120 grains, or 1 eallon l«^nT.t^^"T^^' '*^'. ^%rrf *^^ ^^^^"^ie ^^^^> 57 of ^rbo^ate of Hme^ 1?^ nf !h^"V^ of magnesia, 3| of subphosphate of llumina, 3 of chloride of potassium Ih^oLl^f^ i ^?^^"">,;"d 3 of finely precipitated silica. Put these materials inTo ThP^ tn?Wh^"*^ ""l-'^V^l gasometer F with 353 cubic inches of carbonic acid eas. Then work the machine by the handle of the wheel x, as explained below, and reeulate the introduction of the liquid and the gas in aliquot portions; for ex;mple'T the ri'^' w?hf7«''' v'^^ V^"??5 "^'l'^' ^ '^'^ '^^' ^"^'^tity of liquid'^should b^ ^i ^!i ' ^ ^^? *'"*''^ ^"''^^^ f ^^^ »*"' ^ei'^- «^e half of the whole quan ity. The sul! phureted mineral waters may be imitated in like manner, by taking the nro^rtion/oJ Aeir constituents, as given in Table 11. of Wateks, MikeraL ^ Proportions of of Mr^F V^^p/J"*^' n ''V'^ <^«"J«ine^d series of Newton's Journal, the patent apparatus Of Mr. F. C. Bakewell, of Hampstead, for making soda water is well descrihpVl Ji*h Illustrative figures. The patent^was obtained in krch, 1882 'but how far h^ ^en introduced into practice I have not heard. Its arrangement discovers ingenuity bu?^? no o'j^t ^'tf/ *° P""^^" ^"""^^^^ '^"" '^' P^*^"^ ^PP^^atus of Mr. Tyler. wLh^;* 1320. m the following page represents, according to his latest specification a is the S^' generator, where the chalk and sulphuric acid are mixed; b, the gasometer- c the soda! water pump for forcing the gas; d. the condenser; e, the 8olutioT^(ot Todaj pan f, the bot 1 ng cork; g, the acid bottle, at the right hand shoulder of a- h the wheels fo? working the agitator n the condenser ; i, th^e pipe, for conveying the Vs toThe^ump- rh/ ,^, n.''''"^^" *^^ ?^"*-^" V^^- P"™P' ^' *^^« f°^ regulating the admisdon of the gas into solution ; m drawmg-off pipe leading to the bottling cSrk ; n, the forcing pipe from the pump to the condenser. . ^"rcing The vessel in which the soda water is condensed is lined with silver in order to resist SODA-WATER, ^ ggT IMPROVED SODA-WATER APPARATUS, AS MADE BY MR. HAYWARD TYLER, OF MILTON STREET, Fig. 1318, front view of the soda water machine. Fig, 1319, end view of the sam« f ss"-? Sao •jest: z-ti i^-sx: • r,*' % m ^ s » l2s 8.. •« I. ^ s « «-5 X o *- «£ £ >- S . S ** *i * i o,-"^ S «' S 2 2 3 bc2 hog a o •> i. p 2 w • - o tt> k. 09 n ^ 2 P Sf' a ^^ bo fit)*' 7i O S 1. S3 S C _ _ o '^ c « .o . C 2 €8 ® '^ g c fa-c jg C »=<« C -r— », « s o * CO o «^ g-s-S Q a 5 5S ^ ■** *n -^ -i- a g^^ S=S?"*«t^SP bo»^ ■ J3 ?k"§ •a eg « X «> C S, 5 gc<^ s: >, o " _jae?ct»t — •'«2"o ~- g=5i gl^.^.2^«2 ^^ >.J o^- Sjt fi)fcrr 2 t «.££ ? U3 aea B 3 he a; k. n-l -, n gsTC » -sj^^^sr-^^s^-^^.o 00 'r ^ cS-^ S « = J 1* ^"3 &B c|<^-2 ^25 Sacho«S.ao^5b£-o.a 688 SODIUM. SODIUM, the metallic basis of soda, is obtained by processes similar to those by which potassium is prcjcured. By fusing hydrate of soda with a little hydrate of potassa, a mix- ture is obtained, which yields more readily than soda by itself to the decomposing action of iron-turnings at a high heat, in a bent gun-barrel. The portion of potassium pro- duced may be got rid of, by digesting the alloy for a few days in some naplha or oil of turpentine contained in an open vessel. The sodium remains at the bottom of the liquid. Pure sodium may, however, be prepared at once, by subjecting incinerated tar- trate of soda to heat in the apparatus of Brunner, described under Potassium. It is white, like silver ; softer and more malleable than any other metal, and may be readily reduced into very thin leaves. It preserves its malleability till it approaches the melting point. Its specific gravity is 0'970. It softens at the temperature of 122° F., and at 200° it is perfectly fluid ; but it will not rise in vapor until heated to nearly the melting point of glass. In the air it oxydizcs slowly, and gets covered with a crust of soda; but it does not take fire til! it is made nearly red-hot ; and then it emits brilliant scintilla- tions. When thrown upon water, it is rapidly oxydized, but without kindling, like potassium. If a drop of water be thrown upon it, it becomes so hot by the chemical ae- SOILS, ANALYSIS OF. 689 Jl? i^*jr ^^^t'^' '^T^ ^'^i ^"^ ^^^ °^ «^"" ; >• *»^« «"^»d« ; 2. the oxide, or the basa of common soda; and. 3. the suroxide; the list being formed when eodiuii k • heated to redness upon a plate of silver. «»*^um » -^?2?n^of;«;^^^lP J^r ,• ^^"»g been some time ago engaged in a minute chemical tZetZ lli ?r^ l'^^ ^^'^^ farm, remarkable for perennial fertility without manur^ extent ^ orJ^ied hv'^.r^'^"'" T^^'^'^ T^°^« of analysis, which may to a certaii^ extent be practised by ordinary farmers, and may throw some %ht on the means of miproymg permanently the composition of their lands. The fidd from whic^ thT^p^. subject of analysis was taken, is situated on Marsh Farm, in HrelinTle^eL h, theTrS R M Kerd^u C'^'m d'% rT t' ^'^^* *^^ '^*^---' ^^ neafl^p?o"tl toS Ln app i^^tl?s'fa;m'o^-^n^n' ^' proprietor, informs me that no minure has ever oeen appiieu to this farm of 200 acres, durmg a period of at least fiftv vears exceot once ; and in that season the wheat became so heavy as to be in a^reat meLu^'sSu It produces every variety of crop most abundantly '" ^ *° » ^rent measure spoiled. The substratum, which lies beneath a three-feet bed of the soil is an alluvial denoait replete with decaying vegetable matter; the remains prol^blTof s^e ance^^^ hLdtu^JTed^Jirr.e^^'^^^^^^^^^ 1 *'^ ^f ^^l-- B^^b^LlThVS^^^ aS^Then it w^^stoDPed nL T 11' ^^^T '' «"bmerged till about two centuries uniform texture and appearance; being a finely comminuted friable loam, quite frS from stones, consisting of a fortunate mixture of fine siliceous sand, clay, oxide of iron, and carbonate of lime, with minute proportions of phosphate of lime and magnesia, but very little organic matter. It would seem, there- fore, to derive its principles of fertility chiefly from the atmosphere, and tiie emanations from the subsoil. The specific gravity of the soil, in its average state of dryness, is 2-2 to water called 10; indicating the presence of but little vegetable mater. 100 parts of it collected after a period of ordinary drv weather lose 112 by a steam heat of 212°, and readily re-absorb that por- tion of moisture when again exposed to damp air. When the dried residuum is calcined at a dull red heat, six parts of vegetable substance are burned away; at a higher temperature the carbonate of lime would become calcined, and cause an additional loss of weight, which might inconsiderately be misti^en for organic matter. The first problem in an agricultural analysis, is to find the proportion of calcareous matter, as carbonate and phosphate of lime. Thia may be easily solved with the aid of the fol- lowing instrument {Jiff. 1321.), which may be called the Limestone Meter, one of which was presented and explained by me to the Council of the Royal Society of Agriculture on the 29th of May, 1848. A, is a cylinder of glass, two inches in diameter, and fourteen inches long, graduated on one side with a scale, into spaces of 100 water -grain measures from to 12,000, marked 10, 20, 80, Ac.; and graduated on the other side into spaces of 240 water grain-measures, each. The former scale is used for the analysis of all sorts of alkaline carbonates, and also of acids ; the latter is adapted to the direct analysis of carbonate of lime and marls ; and indirectly to that of phosphate of lime and carbonate of magnesia. • AU the RtsWe-yard dung is sold by the farmer. W{) SOILS, ANALYSIS OP. The cylinder a, has a tubulure in its side near the bottom ; this is closed with a cork, m the axis of which a short glass tube is cemented, hooped externally to a collar of caoutchouc E, which serves as a joint to the upright long glass tube b, heM near its upper - recurved end m a hooked wire. . *^^ The top of the cylinder a is closed with an elastic cork, through a perforation in which the taper tail of the little phial c passes air-tight. The small tube f, open at both its ends, IS cemented on its outer surface, into the bottom of the phial c, so as to close it, whUc the tube itself opens a free passage to gaa, from the shoulder of the phial down mto the cylinder a. ^ The mouth of the phial c is shut with a cork, through which the small end of the tube 1) passes air- tight. The tube d is graduated into spaces of 10, 20, Ac. water-grain measures up to 250, and is closed at top with a stopcock. Its lower and capillary extremity is recurved. In ascertaining with this instrument the proportion of real carbonate of lime, in any lime-stone, marl, or soil, proceed as follows : — Lift out the phial c, and pour water into the cylinder a till it stands about half an inch below the line marked o, and fill up this space with common linseed-oil. Restore the phial c to its place, pressing it in air tight. Then take out its cork with its* graduated tube, and introduce into the phial as many grains weight of the soil or marl as it is proper to operate upon. Of an average limestone 50 grains are sufficient, because the magnified scale of the lime- proof is adapted to the analysis of 50 grains of pure carbonate of lime. Of soils and marls, 100, 200, or even 500 grains, may be taken, because these sub- Btances will rarely contain one- tenth their weight of carbonate of lime. But as the result may always be obtained within five minutes, at the cost of half a farthing, several successive experiments may be made on diflFerent weights of the sample! Having introduced the proper weight of the object into the phial, cover it with water, till this stands a little above the point to which the recurved tube descends. Holding D in the hand, dip its bent point into a phial containing ordinary muriatic (hydrochloric) acid, diluted with its own bulk of water, and applying the mouth to the opened stop-cock, suck up the acid into the tube till this be about two-thirds full, then turn the key of the cock before it is taken from the lip, and the acid will not drop out when the tube is held upright. Replace the cork with its tube d in the phial c. Detach the long tube, b, from its wire-rest with the left hand, and hold its curved extremity above an empty basin ; then with the right hand open the stop cock of d, to let a little acid run down upon the marl, but shut it almost instantly again, lest too much acid should escape, and cause so brisk an effervescence as to occasion an overflow of the mix- ture into the small tube f. The disengaged carbonic acid escapes through the tube f, presses on the surface of the oil in a, and causes a stream of water to flow from the tube B, into the subjacent basin. "When the water ceases to run, open the stop-cock again, when more acid will descend, cause a fresh extrication of gas, and a further flow of water. The curved end of the tube b should be progressively lowered, as the oil falls in a, so as to maintain its level and that in the tube, in the same horizontal plane. When- ever gas ceases to be extricated by the muriatic acid, the experiment is completed, and the number on the lime-meter scale opposite to the upper surface of the oil, denotes the number of grains of carbonate of lime in the quantity of limestone, marl, or soil, put into the phial c for experiment. A little carbonic acid gas remains condensed in the muriatic solution, but tliis is not more than equivalent to the bulk of liquid acid intro- duced into the capacity of the apparatus ; so that no compensation need be made on this account. For the purpose of minute chemical research, that portion of gas may be expelled by surrounding the phial c with a cloth wrung out of hot water, and the volume of dilute acid added may also be taken into the account. Thus the composition of carbo- nates by an acid, and of acids by a bi-carbonate, may be determined by means of this instrument with equal rapidity and precision. The contents of thephial may be poured out into a porcelain capsule, gently heated, and thrown on a filter. The lime of the carbonate, as well as the phosphate of lime and the magnesia, will pass through in solution along with a very little iron. On super-saturating the acidulous liquor with water of pure ammonia, phosphate of lime (if present, will fjill, and may be drained on a filter and dried. Taken off the dried filter, and digested with a little dilute sulphuric acid, sulphate of lime will result, characterized by its entire insolubility in dilute alcohol. Hence the sulphate washed with vinous spirits, dried and calcined, will repre- sent by its weight one-fifth more than the original weight of the phosphate. By the action of the sulphuric acid, the iron precipitated by the ammonia with the phosphate is got rid of The magnesia, unless its proportion has been very great, will all remain dissolved as ammonia-muriate, and its quantity may be ascertained by precipitating it either vith soda, or phosphate of soda. In the former case, the substance obtained, when wa^ed on a filter, dried and ignited, is pure magnesia; in the latter, it is the ammonia- machine. SOILS, ANALYSIS OF. 591 Cv''jf!^t^^°lf'T!''!'* : ^"^ "^^^^ ^"^^ ^t t»>e moderate heat of 120° Fahr it represents ma^esl^ "^"' '"^ '^"^' *'"' "^ *^^ ^^^«'^ P^«««"t; or for 100 parTs^lTi of YenTent:-* '^"^^'*' ^*^^"' ^^ '^" " *^ ^ ™»^«' ^^^ following apparatus is con- hoW iTfels^/rou^rhf' "'f"^"'' f\^ '"J^"^.i" ""' *^^"^^« t»^'n ^^'^^' Tl.is should yl r.u.f} quart of water; and when the soil and dilute acid are introduced it is to this way til every constituent of the soil, except the silicaT becomes duL.lvS ^M , quaatitTlha1,re".i"^ preferred for the analyjis of soils, »d^rJwhat'^''greatr quantity than the bases in the given weight of soil can npufralio- Tn,« f ^1 j Fg™ ™i.ytlu'roo^™iror% rrn-^^? -^"^^f " ^:J!zrl::a fnr «f q\ -^ x^/^^*^*?^ ^^ ^^'^ *° *^® *<^^»o» of boiling dilute acid in this wav rfiit:^\'irsi;:r^^r^i rsL'TJi'^njr:^^^^^^^ |*.ai„s » the "filter having been washed' i'n 2' p" 'ts dr^d! i^^ed:'^ The alumina, iron-oxide, and phosphate of lime thrown Hnwn l,«^ ♦!,« „ being washed in the filter,'and dr?ed I a cheesy TonsiSce? a^eT^moU :ith a™Ze potSThettv 'tt''.r^^ -^^^ ^-* in ai:rutTon\'f p^u^e fw K iu ^ ^u ^^"""'"^ IS dissolved, when its alkaline solution is to be oassed through a filter, then saturated with muriatic acid, and next supersaturated^ wTth action of dilute alcohol, acidulated ^ith sulphuric acid afag^^^^^^^^ heat ftiul h^ iron oxide will be dissolved, and its solution may be passed through a fiher wh^le h! sulphate of lime will remain upon it, to be dried, ignited, and weighed FT;e parts of of «Z?'P"^l5u'' f-""' ^^ P^o«Phate. The iron is obtained by predpUation with water Tr W fi ''*7'r^"^ ^Sniiion.-For phosphoric add, see thfseguel Ihe tirst filtered hquor, with excess of ammonia, contains the lime of the car bonate, and the magnesia. The former is separated by a solution of oxalate of Tm iSonT>f f.^'^'^'r.'". " "^"^r^^ "^^"^*^ ^«^ * ^«- h°"^«' filtratln and very genUe" TJl ■ t^^y^'^.ed dry powder, when the pure carbonate of lime is obtained The magnesia exis ing in the filtered liquor as an amnion ia-muriate, may l^ oEed hv precipitation with soda, or phosphate of soda, as already described ^ ^ it Wnn?*"^ refractory soils, in which the alumina exists as a double or triple silicate t m^,T, t "Tf %*'* ^"'l^^ ^'^'"^ °^ '^^ «^™P^^' i" fi"« powder, mixeS with foS r S! „i 1^^/^ '* ''^•?'*^ carbonate of soda, the mixture being put into a platilim cr^ The ^rnoihrr-"'^ 7 ''? Centre 50 grains of hydrate of ^tash being 1^ The crucible being slowly raised to a red-white heat, affords a fufed liauid nnit^ homogeneous, of a grey or brown colour according to th^ metals present n i M«n ganese gives a purple tint; and iron a reddish brown '^^fLd matter ^hm^lS^" trelt:d "ad^Y; rS""" '"' """""'"^ '=»'""'"«'"' "' *" -'• -d U to be , J- 692 SOILS, ANALYSIS OP. 1 1 ^hiskey (11 per cent, overproof). The whole sulphate of lime will be now separated from the fluid, and after being drained on a filter, may be dried, ignited, and weighed. '' » o » For determining the alkaline salts, the water filtered from the 100 grains of the BoU should be evaporated down to one-fifth of its bulk, and then treated— Ist, with nitrate of barytes, for the sulphates; 2d, with nitrate of silver for the muriates: 3d, with oxalate of ammonia, for the nitrate or muriate of lime (provided no sulphate of ;\?® 18 indicated by the first test); 4th, with litmus paper, for alkaline or acid reaction ; oth, with soda-chlonde of platinum for potash salts, which are very valuable for the growth of many plants. The portion of soil tested for potash salts should, before being digested in water be gently calcined, to insure the expulsion of ever^ particle of ammoniacal salt, otherwise the precipitate afforded by soda-chloride of platinum would be fallacious. Another peculiar research of great importance is that which determines the amount of ammonia in a soil ; and which may exist either ready formed, or in its elements, capable of affording a portion of the azotic food so indispensable to vigorous vegetation. The actual ammonia is easily obtained by distilling the soil along with some "milk of lime. The distilled water will contam all the volatile alkali, which may be measured by the number of drops of a standard dilute acid which it will saturate. The ;)0igest in inixture upon a filteJ, and weSh ^e srinLfift^^S ^''^'- .^^^ , alcohol, throw the this weighMhat of the oxil ?f U^A ^^ ?^ ^^^^ remaining left upon it From contain 112 of oxide Z nnL t ^"^Tx' ^.°«^°.; «i"ce 152 of sulphate of TiS in apother equal portion ofthTtTU^ '"i^''!!"^ *?^ ^*^°°^ ^J ^^^^^ of ^ryt^ n^ea^nstf ThTstSf-chS o^f' fit ''?lif S^" ^' ^"^^ \^ ^^^ <»-% by «nine the quantity of that impoK aTkali as weU iVl^^ 1*^*?^^ ^ ^^^^'^ •oil m hydrochloric acid is to V« troaSS tu I ^^ ^^^ ^« solution of the reddened litmus papT t il then hfff^ ^'^} ^^^'^ ^a*«' ^^^ the hquid blue! the whole of the^sSf^hu c anS ph,^^^^^^^^^^^^ "Pon a filter. By ^s^^^l n.agnesia..and the lim^e that was^cZw" S w th 'tlTe ph'^snh '^' °^i?^°' '^"^ *»>« The precipitate is to be washed till the wallr l^ I Phosphoric acid, is separated, by nitrate of silver To the rW i: f 7^^^^ P*®^» ^^ases to be affected w^th caustic ammonia is \o MrtoXl'^ow'' T*^^*? ^' ammonia mtel is to be left in repose for a Httl^fni - ^7 ^""^^ *" ***« barytes. The whole be thrown upon a fi^e" and washed ke lltrerir^'P^'*' '^"«' ^"^ ^' '^ ^^^'o the residuum is to be ignited in a platinum orlT ^"^"«^^'nff evaporated to dryness, when it can contain oX thralkalfne m...^ T ^^P'"^^' ^ expeVall the amSo^ chlorides. After being'UXd.'ft is tr^^^^oS"^ '"^ ""^r? ^° '^' «** "^ trace of magnesia miy appear (which Sn iT r •'^^''^''^ ^"^« "^^^'^ when a amount of potash is to^be^eSimatlr rL the^eilT'n^^^^ ^^ ^^i^^^^^' ^^ '^ •oda-chloride of platinum. The differenc^ „f t^o^ • l[ *^^ P'^^P'tate produced by of that corresponding to the potash ius^LnV^ "^T^* **^ ^^^ ^^°^« ^"oride an3 and of course ^soda in the b^ ^ """^ ^'^^ ^^^ ^l"*"^'*^ of sodium chloride, of^SX^fn^^^^ ;«JHe p^ss of uniting the surfaces surface, serves, partly hy chemical attracUo^^'d^ ^^ ^,^ ^h^^f .^^^^ ^^ -^ 694 SOY. I .- together. The metals thus united may be either the same or dissimilar ; but the uniting metal must always have an affinity for both. Solders must be, therefore, selected m reference to their appropriate metals. Thus tin-plates are soldered with an alloy con- sisting of from 1 to 2 parts of tin, with 1 of lead ; pewter is soldered with a more fusible alloy, containing a certain proportion of bismuth added to the lead and tin ; iron, copper, and brass are soldered with spelter, an alloy of zinc and copper, in nearly equal parts ; silver, sometimes with pure tin, but generally with sUver-solder, an alloy consisting of 5 parts of silver, 6 of brass, and 2 of zinc ; zinc and lead, with an alloy of from 1 to 2 parts of lead with 1 of tin ; platinum, with fine gold j gold, with an alloy of silver and gold, or of copper and gold ; &c. In all soldering processes, the following conditions must be observed ; 1. the surfaces to be united must be entirely free from oxyde, bright, smooth, and level ; 2. the contact of air must be excluded during the soldering, because it is apt to oxydize one or other of the surfaces, and thus to prevent the formation of an alloy at the points of union. This exclusion of air is effected in various ways. The locksmith encases in loam the objects of iron, or brass, that he wishes to subject to a soldering heat ; the silversmith ajid brasier mix their respective solders with moistened borax powder ; the coppersmith and tinman apply sal ammoniac, rosin, or both, to the cleaned metallic surfaces, before using the soldering-iron to fuse them together with the tin alloy. The strong solder of the coppersmith consists of 8 parts of brass and 1 of zinc ; the latter being added to the former, previously brought into a state of fusion. The crucible must be immediately covered up for two minutes till the combination be completed. The melted alloy is to be then poured out upon a bundle of twigs held over a tub of water, into which it falla in granulations. An alloy of 3 parts of copper and 1 of zinc forms a still stronger solder for the coppersmiths. When several parts are to be soldered successively upon the same piece, the more fusible alloys, containing more zinc, should be used first. A soiler solder for coppersmiths is made with 6 parts of brass, 1 of tin, and 1 of zinc ; the tin being first added to the melted brass, then the zinc ; and the whole well incorporated by stirring. The edges of sheet lead for sulphuric acid chambers, and its concentration pans, arc joined together by melted lead itself, because any solder containing tin would soon be corroded. With this view, the two edges being placed in contact, are flattened down into a long wooden groove, and secured in their situation by a few brass pins driven into the wood. The surfaces are next brightened with a triangular scraper, rubbed over with candle grease, and then covered with a stream of hot melted lead. The riband of lead thus applied is finally equalized by being brought into partial fusion with the plum- ber's conical iron heated to redness ; the contact of air being prevented by sprinkling rosin over the surface. The sheets of lead are thus burned together, in the language of the workmen. • SOLDERING OF LEAD, cuid other metals, is called by ita inventor, M. de Richemont, autogenioua, because it takes place by the fusion of the two edges of the metals them- selves, without interposing another metallic alloy, as a bond of union. He eflFects this purpose, by directing a jet of burning hydrogen gas, from a small moveable beak, upon the two surfaces or edges to be soldered together. Metals thus joined are much less apt to crack asunder at the line of union, by differences of temperature, flexure, dec, than when the common soldering processes are employed. The fusing together the edges of lead sheets, for making sulphuric acid chambers, has been long practised in this country, but it was performed by pouring some of the melted metal along the line of junction, and afterwards removing its excess by means of a plumber's soldering iron. The method of M. Richemont is a great improvement upon that old practice. It is much quicker and more convenient. SOOT (JVbtr defun^e, Suie, Fr. ; Jius, Flatterrus, Germ.) ; is the pulverulent charcoal condensed from the smoke of wood or coal fuel. A watery infusion of the former is said to be antiseptic, probably from its containing some creosote. The soot of pitcoal has not been analyzed with any minuteness. It contains some sul- phate and carbonate of anmiouia, along with bituminous matter. SORBIC ACID, is the same with malic acid ; which sec. SOY, is a liquid condiment, or sauce, imported chiefly from China. It is preparer with a species of white haricots, wheat flour, common salt, and water ; in the propor- tions respectively of 50, 60, 50, and 250 pounds. The haricots are washed, and boiled in water till they become so soft as to yield to the fingers. They are then laid in a flat dish to cool, and kneaded along with the flour, a little of the hot water of the decoctioa being added from time to time. This dough is next spread an inch or an inch and a half thick upon the flat vessel (made of thin staves of bamboo), and when it becomes hoi and mouldy, in two or three days, the cover is raised upon bits of stick, to give free access of air. If a rancid odor is exhaled, and the mass grows green, the process goes on wellj but if it grows black, it must be more freely exposed to the air. As soon as all the sor* SPINNIJ^G. 595 ftce IS covered with green mouldiness, which usually happens in eignt or ten days, the SI W ''"'''''k'!.''^ ^^' °^*""'* ^^ P^*^^ i» t^« ««»«hine for several davs When il J^se^ andVover^d wltVt^^^^^^ ^' T f'"" ^^" ^^«^°^^"^«> ^^^^ info an eaAheS wholhr.drrpH toiThl %^ r"1^' ""^ '^**^'' ^*^^"S the salt dissolved in it. The h^inl nl«!2; f ^T ^^'' "^""^ *^^ ^^'-^^ *' "^^'^^ 'he water stands is noted. The vessd Jjieffs a^lildi^^^^^^^^ "P^^^^y "^^'•^"S ^^^ evening; anl!^ cover IS applied at night, to keep it warm and exclude rain. The more nowprfnl thm •ni »kI ^- 5 "?"'"s- . -As the mass diminishes by evaporation, well water is added • and the digestion i. continued till the salt water has dissolved the whole Tf the flourTnd the haricots ; after which the vessel is left in the sun for a few da7s! as the r^ ouamv .tiri?n/'^WHP'">\"" '^" ^TP^^^""^^^ «f '^' ^«^"tion, whichTpromoted^^rrJiJ stS ^tlil h\^^V^"?th assumed an oily appearance, it is poured nto ba^:^ strained. The clear black liquid is the soy, ready for use. It is not boiled h..f ,« nnt n« SPARRY IRON ORPTI,? """" ''f-^'?^'"V0/ Science, of Stockholm [or 1803. .Ja.u ■ ■■ ™^ 'P"'y '""■ <"■« '5 '^««<' fof the manufacture of oie iron and changes m roasting into magnetic ironstones, discernible by theTvS The m^' f«ture of iron mto bars by mean, of gas, is but in its infanc/; butX iron pT^du^ta ^rSn •' "-""if «<» '» be preferable to that produced by means of XiS^^ to thepuddled iron in bars made by pitcoaL wiaicom, ana w) Jrnn ^i!'^'*^^ •**( ^"""^^^y »^a^« no*- teen found favourable to the production of ^ood iron ; the prmc.ple has therefore been introduced, of distilling the fueTScC vJ^ and usmg the resulting gases, in a state of combustion in the furnace aa^ SHou^ of ^^^ ^ J?,^^ ''*°°- J^^ '■^^"^'«' ^' ^^' ^' *^^ experiment has yet S'trTed are sat^f^ r^^tive vatVo7 ?L^T ^'^f^'''^ e-tendingy the iron distrits of the ContTneut 'S^ ret^Tob^^^^^^^^ ''''''' '' ^"^P« "^^y ^ -f-«<^ fro- the following £ 2.000,000 502,000 448,000 400,000 800,000 190,000 150,000 145,000 76,000 Great Britain - - . United States - - - . France - - . Russia - - - » . Prussian Zolverein - - . I Austria • • - - . Belgium .... * Sweden - - . . . All the other European States - - /e uw .a^^hlJil^^^h,?^^^?^; designates the relative weights of different' bodies under the fame bulk ; thus a cubic foot of water weighs 1000 ounces avoirdupois ; a cubic foot of coal, J350 ; a cubic foot of cast iron, 7280 ; a cubic foot of silver, 10 400 • and a cnW* foot of pure gold, 19,200 ; numbers which represent the specific gravi^^^^ substances, compared to water = 1-000. See Alloy. S'^aviiies oi ine respecUve SPESMArPT^^tT^kJ- ^""fnJ ''^'?P%' ^"'^ *^"' ^^<^'^^ "nder Copper. •I.O PA 7 ' \ F^^'"^ °r Chevreul. In certain species of the cachalot whale ai the Physeter macrocephalus, ursio, mtcrop,, and orthodon, is also the Delph^us S«zJ? eed Th/r^r-'' JV'^"^'^ "^^'^ ^°"^*^"^ * peculiar' kind of stLriuVcaHeJ^r^^ thJ'riJ f ?»' ??>tamed from cavities in the bones of the cranium of the above ceS?^ the richest m this kind of stearine. This being thrown into great filter-Ws the ^r maceti oil i>asses through, and s subsequentlv nurified bv thP^.i^uLr! ^r- i. ^ of potash ley, which precipitates certain i^K by t^rin^^^^^^^^^ in solution. The solid which remains on the filter "rnSt ^u\ez^^^^^^ hie k ^" m^^^t::^\^^b^e:,^rTs^,T^it^ r„zr' ^^ »"-- »« cooiing. wh.. the eeUrn of Chevreul, or pure SMraTace i I ,t° ."'^" '• «?<•"«'')'.«''«« ■'•""ins « msd its hoilinir noini Bi«. p .. »i- V *! j- ..' ■»«'•">« Pomt has now become llfi» F- J^s';a^l^"1twi?M*tt '^"" "*""' •"*""""•• *'•"'"'= •"^« SPINNING. The greatest improvement hitherto made in formine textile fabri«L •mce the era of Arkwright, is due to Mr. G. Bodmer. of Manchestef. ByL^iS 996 SPINNING. waa obuined m 1»24' *"J ?" „eriS rf 14 Teare was expired. It contained the Council, for 7 ye^ '^" ^ ^^^ fibr« oflotton, flax, &c., were Upped and fcrt development of a P'»^J'T''''S%°?2' ,nd blomng, cardii«, drawing, roving, nnlapped through aU the opemtwns of deam^^^^ ^S,^^^^ ^j. ^^^^._^ .^ :^rTh^e^rppturth''e=°^.jnnot^j^.^ Patent of 1835. «. 1 «j TT.*. mrthod aDDlied through aU the foDowing operations ^ th» Vl^:^'^ '^^T^ SrUU^^ma, WS38. lia 18«. of Mr. Botliner. „ ,, , . „„;, ., Onener (" Wolf," in German), which By . roachine g'"!™"^ .''^I'f » ?7„'J a roUer covered with spikes (see^g. 1828) rro;'sstertrurhe'a^|:^g^^^^^^^ rp^irn:,rd°'sp"j^ruVVsrKri^;srfjh^'^^ behind the first blower. without teeth, and over this plate the The first blower has a feeding-plate Uke^g.^^^^^^ .^ . ^ ^^^^^^^ cotton is delivered to the operation of the common b^s, irom wui Paiwi of 1835. Patents of 1824 and 1835. «to a narrow compartment of 4| or 5 inch.. ,^-^' «j^^^^^^^^^^^ lu^Z machines, upon rollers in beautifully level ^.^^ well-cleaned lap^^^^S^ ^^ ^^^ narrow laps are then placed behind a ^f^^f^^^^^S.^^'^^f,^^^^^ edges is first. Instead of the common beater, »^°^«^!.^[> ^^^^^^^ the fibres from on© ased (see/ig. 1824), which opens the cotton still more, and separates ui SPINNING. 69T toother. The cotton is again formed into similar narrow laps, which arc still more equal than the preceding ones, and eight of these laps are then placed behind the carding engines. It was only by applying his lap-machine, patented in 1842, that he succeeded In forming small laps on the blower; without this he could not perform the doffing of the laps without stopping the wire-cloth, and in doing this, an irregular lap would be formed because of the accumulating of the falling cotton in one place while the wire- cloth was standing. Carding Engine.— His patent of 1824 showed a mode of coupling a number of carding engines, the product of which was delivered upon an endless belt or a trough, and at the end of this trough was wound upon a roller. This arrangement Awants no description, •8 it is generally known. I have seen it in use on the Continent. When a set of cards work together, any interruption or stoppage of a single carding engine causes a defect in the produce of the whole lap. Interruption occurred several times a day by the stripping of the main cylinder, and during this operation the missing band or sliver was supplied out of a can, being the produce of a single carding engine working into cans (a spare card). The more objectionable defect was, however, the difference of the product of the carding engine after the main cylinder had been •tripped ; the band or sliver from it will be thin and light until the cards of the main cylinder are again sufficiently filled with cotton, when the band will again assume its proper thickness. Another irregularity was caused by the stripping of the flats or top cards, but was not so fatal as the first one. These defects were of course a serious drawoack in his system of working, the latter of which he provided against in his first patent by stripping the top cards by mechanism ; the former, however, was only conquered by Us invention of the self-strippers for the main cylinders; thus the carding engine may now work from Monday morning till Saturday night without interruption, the cylinders requiring only to be brushed out every evening; the coiir sequence is, that much time is gained, and a very equal, clean, and clear product is obtained. Old carding engines to which he applied his feeders (see ^g.l325).and main cylinder-clearers produce much superior work, and increase the production from 18 to 24 per cent. The main cylinder-clearer consists of a very light cast iron cylinder upon which five, six, or more sets of wire brushes are fixed, which are caused to travel to and frc across the main cylinder ; the surface or periphery of the brushes overrunning the surface or periphery of the main cylinder by 8 or 10 per cent., the brushos thus lifling the cotton out of the teeth of the cards of the main cylinder, and causing the dirt and lumps to fall. As the brushes are not above a quarter-inch in breadth, and travel to and fro, it is clear that no irregularity can take place in the fleece which comes from the doffer; not more than 1 40th part of the breadth of the cylinder being acted upon at the same time. Figs. 1326, 1327. give an idea of the clearer : the mechanism within the clearer, 1325 Patents of 1838 and 1842. ind by which the brushes, a, are caused to travel, is simple and solid. The mam cylinders for the carding engines are made of cast iron, the two sets of arms and rim are cast in the same piece ; when complete, they weigh 50 lbs. less than those made of wood. 698 SPINNING. Th« new lap machine connected with these engines is almost self-acting ; a girl haf only to turn a crank when the lap is full ; by this turn, the full lap is removed and an empty roller put in its place, the band of cotton is cut, and no waste is made. Drawing Frame. — The drawing frame of 1824 was improved, and the improvements patented, in 1835, and others again in 1842. That of 1824 is known in Germany and France, and generally in use. The laps from the carding engine lap-machine are put upon delivering rollers, behind a set of drawing rollers, and from them delivered upon a belt or trough, and again formed into laps similar to those from the carding engines. The next operation formed the laps into untwisted rovings, and the next again into umaller untwisted rovings, or rovings with false twist in them, as infringed upon by Dyer. The false twist was rather objectionable, and in his patent of 1835 he put a number of rovings on the same bobbin, with left and right permanent twist in them. This does very well; there is, however, a little objection to that place in which the twist changes from right to left when it comes to the last operation before spinning. In his patent of 1838, and particularly in that of 1842, he confined the left and right- hand twist to the drawing frame, when he converts two laps into one roving, and forms a roller or bobbin of 14 inches diameter and 15 inches broad, with six separate and twisted rovings wound upon it. {See Jigs. 1328. and 1329.) The twist is given by tubes in two directions, so that it remains in it (see ^g.l329), the tube turns in the same direction, while the roving advances 4 or 5 inches, and then turns in the other direction. These laps or bobbins are then placed behind a machine, which he calls a coil-frame, the most important arrangement of which he claimed already in his patent of 1835. It consists of a slot with a travelling spout, without which the coils can not be formed under pres- sure. Coiling in cotton can not be claimed, as it was done in the first system of cotton spinning. Coil Frame.— The bobbins (^g.l328), are placed behind this machine, and two ends from the bobbin are passed through the drawing rollers and formed into one untwisted sliver or roving in the following manner : When the cotton has passed through the drawing rollers (see ^g. 1330), and calender rollers. A, it is passed through the tube,B, ind the finger, C ; the spindle with its disc, D, revolves in such a proportion as to tak« up the cotton which proceeds from the calender rollers. A, and cause the rovinpi .o be laid down in a spiral line closely one by one, and as the rollers. A, work at a "regular 1328 1329 Patents of 1835, 1838, and 1842, •peed, it is evident that the motion of the finger, C, and the speed of the tube, B, must vary accordingly. The coil, E, is stationary, and is pressed by the lid or lop, F, which slides up the spindle, G, made of tin plate. The cotton enters, through the slot, X, in M' D- It IS quite evident that the finger, C, and spindle, G, only perform one and the ?Zf hpr'^'^r ^"1;''?«*'- ^V^P««^^^.^' ^""^'^ ^'^'^ ^^5^^^' «"d the coil is thus built from below; t is about 8 inches m diameter and 18 inches high when compressed and contains 4| lbs. of cotton. Mr. Bodmer has several modes of farming th^secoSs' but one only is shown here. These coils are placed behind the twist coil frImesTn hatf ^^on TnK^ T\ ''''•? « Vf ''"^J'' ?^ ^^^^"^ * ^^"'^^'^S machine, where they are wound upon rollers side by side, like the lap or bobbin shown in the drawing frame and placed behind the twist coil frame in this state. urawing irame, ana TtTM^ C(n7£rarne.-This frame forms rovings into coils simUar to those above explained, with this diflerence, that the rovings are fine, say, from 1 to 10 hanks per pound, and regularly twisted : their diameter varies from 2| to 5 inches. The saL« machine produces rovings more or less fine, but the diameter of the coils does not differ. i SPINNING. 699 ■ntmnnj k Patents of 1838 and 1842. -88-8 Paindi of 1838 awi 1842. The difference of this machine from that above described consists in the dimensions of their parts, and in its having the spindle, o, and the lid or top, f, revolving, as well as the tube, b. (See Jig. 1331.) In this machine the motion of the spindle, b, is uniform : the spindle, o, however, is connected by the bevel wheels h and i, with a differential motion at the end of the frame, with which the motion of the finger, c, corresponds. The skew wheels, k and l, are connected with the drawing rollers, a. The speed of the tube, b, and the spindle, g, are so proportioned, that while the spindle, g, performs one revolution, and therefore puts one twist into the roving, the tube, b, also performs one revolution, missing so much as will be required to pass through the slot in the cap or disc, d, and lay on it as much of the roving as proceeds from the rollers, a, and in which one twist is contained. Of course the twist of these rovings can be adapted to their fineness aud varied ; but it is evident that, on account of the regularity of the machine and its sim- plicity of movement, the rovings can never be stretched, and much less twist can be put into thera than can be put in the common fly frames. These coils are put behind the spinning machines on shelves or in small cans, open in front ; or they are wound from 24 to 72 ends upon bobbins, and placed upon unlap rollers behind the spinning frames. Coifing Machine for Cardina Engines and Drawing Frames. — These are simple machines, which may be applied to carding engines or drawing frames of any descrip- tion. They form largft coils, 9 inches in diameter and 22 inches long, when on the 700 SPINNING. machine. ^ There are two spindles, a, (see jig. 1382.) on each machine, for the purpose of doffiog; withont stopping the drawing frame and caraing engines. When one eoil it Vattfids of J 849 filled, the finger, h, is just brought over to the other spindle, so that the full coil is stopped and the new one begins to be formed without the slightest interruption of the machine. Mr. B. forms coils in various ways, also in cans ; but this description is suflRcient to show the application of this mode of winding up bands or rovings. Several of the above- described machines are adopted with equal success to wool and flax. In his patents of 1835, 1837, and 1838, he shows several modes of applying his system to cotton and other machinery. He winds directly from the carding engines the slivers separately upon long bobbins, and he gives them twist in two directions, for the purpose of uniting the fibres to some extent, so that they not only come off the bobbins without sticking to one another, but also that they may draw smoother. He also showed a machine, by which several rovings, say 4 or more, are put upon the same bobbin with conical ends; these bobbins are placed behind the mules or throstles, and are unwound by a belt or strap running parallel with the fluted rollers of the spinning machine as seen in^^. 1338. The belt or band a, is worked in a similar way to that described in his former patent, and the bobbins, b, rest upon and revolve upon their surface, exactly according to the speed of the belt. It is auite evident that the whole set of rovings must be unwound exactly at the same speed, and that no stretching can take place. He can put real and reversed twist in these rovings as well as fabe twist only. The most important feature in the roving machine is a metal plate, in which a slot is formed through which the rovings pass; this slot is seen in jigi, 1334, 1835, and 1336. The cotton when coming from the drawing rollers is passed through the twisters, c, and through the slot in the plate, D. Thus he is enabled to put any convenient number of neatly formed and per- fectly separate coils upon the wooden barrel or bobbin. The bobbin formed upon these machines is represented vajig. 1337., and the conical ends are formed by a mechanism, by which the twisters, c, are caused to approach a little more to one another, after each layer of rovings has been coiled round the barrel : the section of the bobbin is therefore like that shown in fig. 1337. He makes use of exactly the same arrangements, viz., a finger trayelling along a slot in a plate, for the purpose of forming the coils, which has Deen already described. Bovings wound upon bobbins by means of tubes revolving in one direction are cer* SPINNING. 701 1JjS4 ■ ■■ Till II H Ihl III! ii Ttra^ AAAiS 1336 1336 W^ty^yg: PatMi of 1835. fi1=F 1 — V ^^ ^ 1 / -IT ^ 1837 teinly not so fit for spinning as rovings into which a smaU degree of twist is put. The tube by which a twist is put in on one side and taken out at the othercuSs ^ ruffleS ^th Sr*^ '*^'''.'' '? ^^^^^ °"^ ^« "^ P^««^^ between he rolSs, wWIe r^« with a httle permanent twist in them are held together in the nrnPP« nf^ri^lv^ ^ thus produce smooth yam. To remedy the evU above described when ^inLI^J^J^' ^ There is a little defect in the working of the rovings with rever«.i»d twict «Ko- ♦^ SS'er ''^s^d!? eir ^' '' ^"; ^? *' V^ "^^^ "^« win^g mach^et nTkep'^'i^^^ ^\\^?^^.w y proceeds from the change in the twist of the roving seen at A H^ 1338 ; in this place the twist is not like that at B, and it would, in some S Sf the 1338 " ' — ^-^ ^<^J^^ ^ B S yam, be detected under circumstances lust descrihp/? Tn *.«««» «a j . , are used, the twisters are so arranged i^to pnt'hftWi.t in^^^ double rovings Jig. 1339 ; in this case the reversing place of one rovW mi?t!*'tt '*"♦!? f '/'. ^^""^^ ^^ Other, and the fault is completely rectified. ^ ^^ ^® ^""^^ P^*^^ *»^ ^« 1339 SPIRITS. SPIRITS. 703 702 W with the xnule arc contained in the --^^^^^^^^^^^^ LtrfVw^TmVe:' ^f. i;Slcs,as seen in fig- l^^O « and &, the ^elf-actors to e ^^ ^^.^^ ^^^ ^^^ ^^ 1340 bands and shaftswith the self-actor, or rather partly self-actor. A girl of fifteen or sixteen years old stands at X between a and &, and never leaves her place except, perhaps, for aiding in doffing or in banding the spindles. The gearing of the room acts by means of straps upon the machines a and 6, and from these machines all the movements axe given to the six mules, namely, the motion of the rollers, the spmdles, the drawing out of the carnage, the after draft, &c. When the carnages are to be put up, the girl takes hold of two levers of the machine a, and by moving them in certain pr(^ portions, mcts upon two cones and pulleys, and thus causes, m the most easy and certain manner, the car- riages to run in and the yarn to be wound on the spindles The first machine Mr. B. made for this pur pose was completely self-acting, but he found very soon that the me- chanism was more complicated and apt to go out of order than that of . the above-described machine ; and as it is necessary to have a girl of a certain ay to watc^^ over the Piece- [^^^^^^^ dumber of mules, he prefenred the simplified maclnne , P ^c^ JgJ ^^^ ^,, overlooked machines, from whence the yl^^^J «^^°f ^^^fed ^^ this impediment to the as the creeis behind tne mules are n^^^^^J^^^^'^i^ege machines for the purpose of ^l-.f.'l:fim^elUnZ^eI^^^ self-actors; they are equally ^i^^T^z^^"^^ ^^.S wih^i; :;X tmtT^t asi; Tcry simple bastard fr^'^^" H fhVthev can JL handled about without any danger of in jig.l34l,and wound so hard hat they can ^^ hanai ^^^^^ one third •^ 1341 spoiling them; \^f ^ l^^^J^^f self-actors. The machme la "^o'^e yarn than the best cops oi s circumstances in the /r: U-r^^--, extremely simple; but ^^^^^^S^^^f* ^^°J^^ "e has not been able QX -'b :^^-^ constniction of the wmders and P**^^/' f^^^^'^A^^ no. 20's. "^^^ U) spin fvantageously upon large mac^^^^^^^ He has spun on it No. 56 and most ^^autiful y^n The quani y ^^ ^^^^^^ ^^ produces is nearly one third more ^^^^^^^^^^^^^/^^^^^^^^ the?e is a copping Spindles, and the yarn and cops are much superior. J^ . continuous, as weU motion connected with the machine: ^^ ^^^^^^i^f'^S^^^ Jhe '"spirit of ammonia, is, property speaking, alcohol combined .ith ammon.a gaa; nr checks the fermenting process, though a gi^^at aeai oi i ^^^^^^^. "uLtnged. Mr. Sheruian '- -S^,'" "^.X '^^' ^1^ 's^^rU^i"" i^forn,ed. For Z tj;£TlT:Z ITiXth-i ; ^L'U 'connected U. a 50-^^^^^, lorked by machinery, thus continually ^«";°""J.'^ '"Sol readily distils at » ^^ZtS\^^^^. ^Sr^^Vilur dt^^f tat is not injurious to th. W( B Patents of 1888 and 1842. fermentation, provided that it be communicated by the air of a stove-room, and not by water or steam pipes traversing the liquid, which would inevitably scald or seeth the particles in succession, and thereby extinguish the fermenting principle. By the above ingenious plan, Mr. Sheridan tells me he has obtained 28 gallons of proof spirit from a quarter of grain, instead of the average product, 21, being an increase of 25 per cent. The experiment was tried upon a considerable scale at Messrs. Currie'a great distillery near London ; but could not be established as a mode of manufacture, on account of the excise laws, which prohibit the distillers from carrying on the two pro- cesses of fermentation and distillation at the same time. Consumption of Spirits— According to a return recently made, the total number of gallons of proof spirits distilled in the United Kingdom during the year ending January 5, 1860, was 24,775,128, distributed among the three kingdoms thus : — England, 6,573,411 gallons, of which 5,865,600 were from raalt with unmalted grain 17 837 from sugar or molasses with unmalted grain, 13,941 from sugar, and 176,553 from molasses; Scotland 10,846,634 gallons, of which 6,058,086 were from malt only, and 4,788,554 from malt with unmalted grain; Ireland, 8,355,883 gallons, of whicli 85,756 were from malt only, 8,047,077 from malt with unmalted grain, and 222,250 from sugar or molasses with unmalted grain. The number of gallons of proof spirits on which duty was paid for home consumption in the United Kingdom was 22,962,012. the total amount of duty , ^o^;2fo'oPi: ^*' distributed as follows : — England, 676,036 gaUons from malt only, 8,166,226 from malt mixed with unmalted grain, 14,740 from sugar, and 177,052 from molasses; total. 9,053,676 gallons, on which 3,546,023/. 2s. duty was paid, at the rate of Is. lOd per gallon ; Scotland, 4,950,736 gallons from malt only; 1,984,115 from malt mixed with unmalted grain, and 152 from sugar; total. 6,936,003 gallons, on which the duty, at 3s. Sd. per gallon, amounted to 1,271,417/. 4«. 4d ; Ireland, 452,468 gallons from malt only, 6,404,770 from malt mixed with unmalted grain, 112,308 from sugar or molasses with unmalted grain, and 3,787 from sugar; total, 6.973,833 gallons, yieldmg, at the rate of 2a. 8d. per gallon, an amount of duty equal to 929,777/. 14«. Sd. Y04 SPIRITS. SPIRITS. 705 SPIRITS. Correspondence between Specific Gravity and per Centa. over Proof at «f P Specific ] OraTtij. C Per Cent. Specific Per Cent. Specific »ver Proof. Gravity. ver Proof. Gravity. 0-8890 67-0 •8455 517 •8748 •8160 668 •8459 515 •8751 •8163 66^fi •8463 51-3 •8755 •8167 66' 5 •8465 511 •8758 •8170 66 3 •8469 509 •6762 •8174 66' 1 •8472 50-7 •8765 •8178 65-6 ■8476 50-5 •8769 •8181 658 •8480 50-3 ■8773 •8185 65-6 •8483 501 •8776 •8188 655 •8486 49-9 •8779 •8I0S 65-3 •8490 49^7 •8783 •8196 65 1 •8493 495 -8786 •8199 650 •8496 49*3 •8790 •8203 648 •8499 49-1 •8793 •8306 64-7 •8503 489 •8797 •8310 64-5 •8506 487 •8800 -BM 643 •8510 48-5 •8804 8318 64 1 •8513 48-3 •8807 •8221 64 •8516 480 '8811 •8334 638 •8520 47-8 •8814 •6337 636 •8523 476 •8818 •8331 634 •8527 474 -8822 •8334 633 •8530 473 •8825 8338 63.1 •8533 470 •8829 •8S4S 63-9 •8537 468 •8833 •8345 63-7 •8540 466 •8836 •8249 63-5 •8543 464 •8840 •8252 633 •8547 46-3 •8843 •8256 63-3 •8550 460 •8847 •8259 630 •8553 45-8 •8850 •8363 618 •8556 456 -8854 •8260 616 •8560 45'4 •8858 •8370 61*4 •8563 453 •8861 •8373 613 •8566 450 •8865 •8277 61-1 •8570 44-8 •8869 •8280 609 •8573 446 •8873 •8284 60-7 •8577 444 •8876 •8387 60-5 •8581 44-3 •8879 •8391 604 •8583 439 •8883 '8394 603 •8587 43-7 •8886 •8398 600 •8590 435 •8890 •8301 59-8 •8594 433 '8894 •8305 596 •8597 431 •8897 •8308 595 •8601 438 •8901 ■8313 69-3 •8604 43*6 •8904 •8315 591 •8608 434 •8908 •8319 58-9 •8611 43-3 •8913 •8333 58-7 •8615 420 •8915 •8336 586 •8618 417 •8919 •8339 58-4 •8023 41-5 •8923 •8333 583 •8625 41-3 •8926 •8336 580 •8629 41-1 •8930 •8340 57-8 •8633 40-9 •8933 •8344 577 '8636 400 •8937 •8347 67-5 •8639 404 •8940 •8351 57-3 '8643 403 •8944 •8S54 671 •8646 400 •8948 •8158 56'9 '8650 398 •8951 •8363 568 •8653 39-5 •8955 •8365 566 •8657 393 •8959 •8369 564 •8660 391 •8963 •8373 563 •8664 38 9 •8966 •8376 56-0 •8667 38-7 •6970 1 *• — ^ •8379 559 •8671 38-4 •8974 •8383 55-7 •8674 38-3 •8977 •8380 555 •8678 380 •8981 '8390 55-3 •8681 37 8 •8985 '8393 551 •8685 376 •8989 •8396 55-0 '8688 373 •8993 •8400 548 •8699 371 •8996 •8403 54-6 •8695 369 •9000 •8407 54-4 •8699 367 •9004 •8410 543 '8703 364 •9008 •8413 541 •8706 362 •9011 •8417 53-9 •8709 359 •9015 •8420 53-7 •8713 35-7 •9019 •8434 535 •8716 355 •9023 •8437 53-3 •8720 352 •9026 •8431 53-1 •8733 350 •9030 '8434 52-9 •8727 847 •9034 8438 537 -8730 34-5 •9038 '8441 535 -8734 343 •9041 '£445 533 -8737 34 1 •9045 ■8448 531 •8741 33-8 •9049 •845t ftl9 -8744 336 •MSt Per Cent Over Proof. 334 333 339 337 334 33-3 330 317 315 31-3 310 308 305 30-3 300 39-8 295 39 3 290 288 385 283 28-0 37-8 275 37-3 370 368 365 363 360 358 355 35-3 350 348 345 34-3 34*0 33-8 23-5 232 23-0 22-7 225 232 219 217 21*4 21-3 20-9 306 90*4 201 19-9 196 19-3 191 188 186 18 3 180 17-7 175 17 9 16^9 16-6 16-4 16-1 15^9 15-6 15-3 150 148 145 143 139 13-6 13*4 131 13-8 13-5 13-3 ISO 11-7 Specific Gravity. Per Cent Over Proof. ■9056 ■9060 ■9064 •9067 •9071 •9075 •9079 •9083 •9085 •9089 •9093 •9097 •9000 •9104 •9107 •9111 •9115 •9118 •9133 •9136 •9130 •9134 •9137 •9141 •9145 •9148 •9153 •9156 9159 •9163 ♦9167 •9170 •9174 •9178 •9183 •9185 •9189 •9193 •9196 •9200 Under •9204 •9207 •9210 •9314 •9218 9223 •9336 9939 •9333 9237 •9341 •9344 •9348 •9259 •9855 •9959 ■9963 •9267 •9370 •9274 •9378 •9383 •9386 •9991 •9295 •9299 '9309 •9306 •9310 •9314 •9318 •9329 •9336 •9339 •9333 •9337 •9341 •9345 •9349 •9353 •9357 •9360 •9364 •9368 114 HI 108 106 10-3 100 97 9-4 99 89 86 8S 80 77 7^4 71 66 6-5 6-9 5-9 I 56 5-3 50 48 45 49 i'9 S-6 33 30 97 3-4 31 1-9 16 1-3 10 0-7 03 Proof Proof. 0^3 0-6 09 13 1-6 19 99 95 9-8 31 34 17 40 4-4 47 SO 5S 67 60 64 6-7 70 7-S 7-7 80 8-3 86 90 93 97 loo lOS lO^T 110 ir4 irt I9^1 134 13-S 131 IS'6 13-0 ^•t 14-t \ Table — continued. I Specific Per Cent. Specific Per Cent. Specific Per Cent. Specific PerCoKt 1 Gravity. Under Prf. Gravity. Under Prf. Gravity. Under Prf. Gravity. Under Prf. 1 •9373 14-9 9530 310 •9685 522 •9846 79-3 1 -9376 1 •9380 15 3 •9534 31-4 •9689 529 •9850 798 15-7 •9539 311 •9693 533 •9854 80-4 1 •9384 160 9542 32-8 •9697 542 •9858 81 1 •9388 16-4 -9546 32-8 •9701 54^8 -9862 817 •9392 167 -9550 332 •9705 555 ■9866 823 •9396 171 •9553 33 7 •9709 56 2 •9&70 829 •9399 175 -9557 34-2 •9713 569 •9874 83-5 •0403 178 •9561 34 6 •9718 576 •9878 840 •9407 182 •9565 35 1 •9722 58-3 •9882 84-6 •9411 185 •9569 356 •9726 590 •9886 858 •9415 18-9 •9573 361 •9730 59-7 •9890 85*8 •9419 19 3 •9577 866 •9734 60-4 •9894 863 ■9422 197 •9580 371 •9738 611 -9698 869 -9425 20 •9584 376 •9742 61-8 •9902 87 4 •9430 304 •9588 381 •9746 62-5 •9906 880 •9434 208 •9592 386 •9750 632 •9910 885 -9437 21 2 •9596 39 1 •9754 639 •9914 891 I -9441 216 •9599 396 •9758 64 6 •9918 896 •9445 21 9 •9eo3 401 •9762 653 •9922 90.3 •9148 223 •9607 406 •9766 660 9926 90-7 -9452 22 7 •9611 411 •9770 667 •9930 91-2 ■9456 23-1 •9615 417 •9774 674 •9934 917 • •9460 235 •9619 422 •9778 68-0 ■9938 923 9464 239 •9623 42-8 •9782 68^7 •9942 92-8 , -9468 243 •96«7 433 •9786 694 •9946 933 •9 172 247 •9631 43 9 •9790 701 •9950 938 ■»476 25 1 •9635 444 ■9794 708 •9954 943 •9480 25 5 •9638 450 •9798 714 •9958 94 9 •9484 25-9 •9642 455 9802 72-1 ♦9963 95-4 •9488 26-3 •9646 4«1 •9806 728 •9966 959 •9492 267 •9650 46-7 '9810 735 •9970 96.4 ■9496 271 •9654 473 ■9814 741 •9974 968 •9i99 •95(13 875 -9657 479 ■9816 74^8 •9978 97 1 28-0 •9661 485 •9822 754 •9983 97-7 •9507 284 •9665 491 •9826 7«1 •9986 983 •9511 •9515 28^8 •9669 497 •9830 76-7 •9990 98-7 29-2 •9674 50-3 •9834 773 •9993 99-1 •9519 •9522 •9526 29-7 301 30iJ •9677 •9661 510 516 •9838 •9842 78-0 786 -9997 10000 91.6 lOOO The total number of gallons of proof spirits imported into England in the year ending January 6, 1850, from Scotland, amounted to 2,651,529 gallons, of which 678,342 were distilled from malt only, and 1,978,187 from a mixture of malt with unmalted grain ; and the total amount of duty paid thereon, at the rate of Is. lOd. per gallon, was 1,038,'5164 10«. 6rf., being 513,3.30/. 8«. on removal from bond, and 525,185/. 2«. 6«i after arrival at the place of destination. The number of gallons imported from Ireland was 890 021 of which 1,694 were from malt only, 884,772 from malt with unmalted grain, 3,285 firom sugar or molasses with grain, and 270 from sugar ; and the total amount of duty paid was 348,591/. 11«. 2d., being 118,912/. Is. 6d. on removal from bond, and 229,679/. 3^8dL after arrival at the place of destination. The number of gallons imported from Scotland mto Ireland was 766,405, of which 396,064 were from malt only, 370,205 from malt mixed with gram, and 136 from sugar, the amount of duty paid, at the rate of 2*. 8^^g exposed to the heat of a glass-kiln, preserves its color unimpaireJ. while the modern suffers considerable injury, and in ^^^^^^ fi*^Tp'"ffp\hrior ^ Hence the latter cannot be painted upon, as the heat requir^ to fix the fresh color would destroy the beauty of the original basis. To obviate this difficulty, the artist paints uj^n a piece of plain glass the tints and shadows necessary for blending the rich ruby g.ow whh the other pirts of his picture, leaving those parts untouched where he wishes he ruby to appear in undiminished brilliancy, and fixes the ^J^hyglassjn the picture b^^^^^^^ the painted piece, so that in such parts the window is double S^f^^.^' ^f* ^f " '^^^ ploys, as did the late Mr. Muss, chrome oxyde alone for greens ; and he rejects the use ofiron and manganese in his enamel colors. , . ., , „„m wvo«/*w* nr^ Colored transparent glass is applied as enamel in silver and ^^^^^^^^^e^n's viously bright-cut in the metal with the graver or the rose-engine The c^ts, reflectin| the rays of light from their numerous surfaces, exhibit through the glass, "chly stained with gold, silfer, copper, cobalt, &c., a gorgeous play of P"sn^atic co ors varied with every change of aspect. When the enamel is to be painted on it should be made opal- e»cent by oxyde of arsenic, in order to produce the most agreeable eflect. The artist in enamel has obtained from modern chemistry, preparations of the metali platinum, uranium, and chromium, which furnish four of the richest and most useful colors of his palette. Oxyde of platinum produces a substantive "c^ h^^o^^Jormerl; unknown in enamel painting; a beautiful transparent tmt, which no intensity or repeti- tion of fire can injure. Colors proper for enamel pamting, he says, are not to be pur- chased ; those sold for the purpose, are adapted only for painting upon clnna The con- stituents of the green enamel used by his brother, Mr. W. Essex, are, silica, borax, oxyde °'»s:fx?s%t^m^^^^^^^^ is a cubic space of about ,2 inches -d contains fire-clay muffle, without either bottom or back, which is surrounded ^^th coke, except i» front. The entire draught of air which suppUes the furnace, passes through the muffle; the plates and paintings being placed ««, V';%'^'t "J^.f AsTe .r^^^^^^^^^ clay, technically termed planche, which rests on the bed of coke-fuel. As the greatest heat is at the back of the muffle, the picture must be turned round ^hUc in the fire, bv means of a pair of spring tongs. The above furnace serves for objects up to tve S^cSSSid^e^ter; butV larger works a different furnace is required, for the descnp. tionofwhich I must refer to the original paper. ijr^^ «„ „!««» Relatively to the receipts for enamel colors, and for staining and g'^ing on glas^ for 1th twenty guineas were voted by the Society for the Encouragement of Art^m the session of 1817, to Mr. R. Wynn, Mr. A. Essex says, in p. 446 of his essay J^heunrtunaJe artist who shall aUempt to make colors for the V-rvo.eo^v^rnU^^^^^^ enamel from these receipts, will assuredly find, to his disappointment that they ar^^ut^ terlv useless." In page 449 he institutes a comparison between Mr. Wynn s complex frrrlgofbr green" as^ublished in the Transactions of the Society, ^^/th the simple reS of hi! brother, as given above. It is a remarkable circumstance, that not one of cur enamel artists, dJirin| a period of twenty years, should have denounced Uie falUc, of these receipts, and the folly of sanctioning imposture hy a public reward. Should Sir. Essex's animidversions be just, the well-intentioned Soc ety H^^^^^ ^ddphi^^^^^^ the negligence of its committee, come to merit the sobnquety « For the Discouragemem "^Ae^'blues of vitrified colours are all obtained from the oxide of cobalt Cobalt ore (Bulph^et) being weU roasted at a dull red heat, to dissipate all the sul- ^m^dZ^uxc iflllissolved.in somewhat dilute nitric acid, and after the addi tion of much water to the saturated solution, the oxide is precipitated by carbonate of soda, then washed upon a filter, and dried. The powder is to be mixed with thrice its weight of saltpetre ; the mixture is to be deflagrated in a crucible, by applying a red hot cinder to it, then exposed to the heat of ignition, washed, and dried. Three parts of this oxide are to be mixed vrith a flux, consisting of white sand, borax, nitre, and a little chalk, subjected to fusion for an hour, and then ground down into an enamel powder for use. Blues of any shade or intensity may be obtained from the above, by mixing it with more or less flux. The beautiful greenish yellow, of which color so many ornamental glass vessels have been lately imported from Germany, is made in Bohemia by the following process. Ore of uranium, Uran-ochre, or Uran-glimmer, in fine powder, being roasted, and dissolved in nitric acid ; the filtered solution is to be freed from any lead present in it, by the cautious addition of dilute sulphuric acid. The clear green solution is to be evapora- ted to dryness, and the mass ignited till it becomes yellow. One part of this oxide is to be mixed with 3 or more parts of a flux, consisting of 4 parts of red lead and 1 of ground flints ; the whole fused together and then reduced to powder. Chrome Green. Triturate together in a mortar equal parts of chromate of potash and flowers of sulphur : put the mixture into a crucible and fuse. Pour out the fluid mass ; when cool, grind and wash well with water to remove the sulphuret of potash and to leave the beautiful green oxide of chrome. This is to be collected upon a filter, dried, rubbed down along with thrice its weight of a flux, consisting of 4 parts of red lead and 1 part of ground flints fused into a transparent glass ; the whole is now to be melted and afterward reduced to a fine powder. Violet. One part of calcined black oxide of manganese, one of zaffre, ten parts of white glass pounded, and one of red lead, mixed, fused, and ground. Or gold purple (Cassius's purple precipitate) with chlorsilver previously fused, with ten times its weight of a flux, consisting of ground quartz, borax, and red lead, all melted together; solution of tin being dropped into a large qua titv of water, solution of nitrate of silver may be first added, and then solution of gold in agua regia, in proper proportion* .The precipitate to be mixed with flux and fused. Exhibition Stained Glass Windows. — Leaded work with medallions and ornamental work of the early Gothic style ; and in the style of the fourteenth century, the figures being St. Peter and St. Paul, St. George and Britannia; armorial decoration; a land- scape and ornamental work suitable for a dwelling house. Flowers painted and enamelled on a large plate of glass, with borders ; the glass having been burnt in a kiln four times. The interest attached to this beautiful art, and its comparatively recent revival, calls for a few remarks. Its antiquity is undoubted. Pliny speaks of " coloured glasses made to imitate precious stones and gems," and painted glass in the church of Notre Darae at Paris is described as early as the sixth centurv. To Suggerius Abbot of St Denis, in 1150, is probably owing the reintroWuction of painted glasses in churches. How rapidly his example was followed, is proved by the magnificent glass of the thirteenth century abounding on the continent, and partially existing in this country, the oldest examples we have being in Canterbury Cathedral. At first the ornaments consisted of a mere drapering ; then rude representations of saints and kings; then panels of various forms, with subjects from the Testaments, on grounds of blue or ruby, the intermediate parts filled with Mosaic patterns in rich colours, and the whole enclosed within a coloured border. In later styles single figures predominated, with flowing patterns of foliage and later still, with canopies over them. Some of the finest works are by French and Flemish artists ; and this art was traditionally known to the early Florentine painter Cimabue who is said to have introduced it into Italy. Probably our actual obligations are due to our Norman neighbours, as a necessary appendage to their architecture. It has been a popular notion thjtt this art was lost to us ; such is not the case ; it has indeed been dormant, but nevei extinct. STAMPING OF METALS. The following ingenious machine for manufacturing metal spoons, forks, and other articles, was made the subject of a patent by Jonathan Hayne, of Clerkenwell, in May, 1833. He employs a stamping-machine with dies, ia which the hammer is raised to a height between guides, and is let fall by a trigger. He prefers fixing the protuberant or relief portion of the die to the stationary block or bed of the staropmg-machine, and the counterpart or intaglio to the falling hammer or ram. The peculiar feature of improvement in this manufacture consists in producing the spoon, ladle, or fork perfect at one blow in the stamping-machine, and requiring no further manipulation of shaping, but simply trimming off the barb or fin, and polishing the surface, to render the article perfect and finished. Heretofore, in employing a stamping-machine, or fly-press, for manufacturing spoons, ladles, and forks, it has been the practice to give the impressions to the handles, and to 719 STAMPING OF METALS. the bowls or prongs, by distinct operations of different dies, and aAer having so par. tially produced the pattern upon the article, the handles had to be bent and formed by the operations of filing and hammering. ^ ^ » j j ii«— By his improved form of dies, which, having curved surfaces and bevelled edges, allow of no parts of the faces of the die and counter^ie to come into contact, he is enabled to produce considerable elevaUons of pattern and form, and to bring up the article pertecl at one blow, with only a slight barb or fin upon its edge. , ,. /. . • In the accompanying drawings, fig. 1344 is the lower or bed die for producing m •peon, seen edgewise j fig. 1345 is the face of the upper or counter^ie, corresponding ; 1345 Jig. 1846. IS a section, taken through the middle of the pair of dies, showing the space in which the metal is pressed to form the spoon. . ^^ To manufacture spoons, ladles, or forks according to his improved process, he first forffea out the ingot into flat pieces, of the shape and dimension of the die of the intended article ; and if a spoon or ladle is to be made, gives a slight degree of concavity to the bowl part ; but, if necessary, bends the back, in order that it may lie more steadily and bend more accurately, upon the lower die ; if a fork, he cuts or otherwise remove portions of the metal at those parts which will intervene between the prongs ; and, Kving thus produced the rude embryo of the intended article, scrapes its entire surface clean and free from oxidation-scale or fire-strain, when it is ready to be introduced mto the stamping-machine. , . , . , ^ ■ ax. He now fixes the lower die in the bed of the stampmg-machme, shown at a, a, in the elevations figs. 1347. and 1348., and fixes, in the hammer b, the upper or counter-dw c, accurately adjusting ti.om both, so that they may correspond exactly when brought loeether. He then places the rudely-formed article above described upon the lower ^ die, and having drawn up the 1347 hammer to a sufficient elevation by a windlass and rope, or othei ordinary means, lets go the trigger, and allows the hammer with the counter-die to fall upon the undei die, on which the article is placed ; when, by the blow thus given to the metal, the true and perfect figure and pattern of the spoon, ladle, or fork is produced, and which, as before said, will only require the removal of the slight edging of barb or fin, with polish- ing, to finish it. On striking the blow, in the operation of stamping the article, the hammer will recoil and fly up some distance, and if allowed 16 fall again with reiterated blows, would injure both the article and the dies; therefore, to avoid this inconvenience, he causes the ham- mer on recoiling to be caught by a pair of palls locking into rack* I on the face of the standards, seen in figsVlUl and 1348^ In fig. 1347 the hammer 6. of the stamping-machine, is seen STARCH. 711 raised and suspended by a rope attached to a pair of jointed hooks or holders d, J, the lower ends of which pass into eyes «, «, extending from the top of the hammer. When the lever or trigger t is drawn forward, as in^fg. 1046, the two inclined planes g, g, on the axle A, press the two legs of the holders d, rf, inward, and cause their hooks or lower ends to be withdrawn from the eyes e, e, when the hammer instantly falls, and brings the dies together : such is the ordinary construction of the stamping-machine. On the hammer falling from a considerable elevation, the violence of the blow causes it to recoil and bound upwards, as before mentioned ; it therefore becomes necessary to catch the hammer when it has rebounded, in order to prevent the dies coming again to- gether; this is done by the following mechanism: — Two latch levers t, i, are connected by joints to the upper part of the hammer, and two pall levers k, k, turning upon pins, are mounted in the bridge /, afiixed to the ham- mer. Two springs m, m, act against the lower arms of these levers, and press them outwards, for the purpose of throwing the palls at the lower ends of the levers into the teeth of the ratchet racks n, n, fixed on the sides of the upright standards. Previously to raising the hammer, the upper ends of the pall levers fr, are drawn back, and the latches t, being brought down upon them, as in fig. 1045, the levers k are con- fined, and their palls prevented from striking into the side racks ; but as the hammer falls, the ends of the latches t strike upon the fingers o, o, fixed to the side standards, and liberate the palls, the lower ends of which, when the hammer rebounds, after stamping, catch into the teeth of the racks, as in fig. 1046, and thereby prevent the hammer from again descending. STANNATE OR STANNITE OF POTASH AND SODA. Stannates and stannitea of alkalis are valuable mordants in calico printing, and are prepared by the patented plan of Messrs. Greenwood, Church and Barnes, as foUowa For the staunate of soda: 2S pounds of caustic soda are first put into an iron crucible, heated to a low red heat, till the hydrate be produced ; to which 8 pounds of nitrate of soda and 4 pounds of common salt are introduced. When the mixture is at a ^uxing heat, 10 pounds of feathered block tin are added, and it is stirred with an iron rod. The mass now becomes dark coloured, and pasty, and ammonia is given off (the tin decomposing the water of the hydrated soda and part of the nitrate of soda.) The stirring is continued, as well as the heat, till deflagra- tion takes place, and the mass becomes redhot, and pasty. Tliis product is stannate of eoda. It may be purified by solution and crystallization. Stannite of soda is made by putting 4 pounds of common salt, 13^^ pounds of caustic soda, and 4 pounds of feathered block tin into a hot iron crucible over a fire, and stirring and boiling to dryness, and as long as ammonia is given off What remains is stannite of soda. To produce the tin preparing Hqnor, 3 pounds of stannate of soda are dissolved in one gallon of boiling water, and 3 gallons or more of cold water, to bring it to the required strength. The stannite of soda is treated in the same way. The potash-stannate and stannite are prepared in like manner. These dilute liquors are thus prepared (or the dyers and printers. STARCH (jlmidorij Fecule, Fr; Starke, Germ.), is a white pulverulent substance, composed of microscopic spheroids, which are bags containing the amylaceous matter. It exists in a great many different plants, and varies merely in the form and size of its microscopic particles ; as found in some plants, it consists of spherical particles i of an inch in diameter; and in others, of ovoid particles, of ^i_ or -i_ of an inch. It oc- curs, 1. in the seeds of all the acotyiedinous plants, among which are the several species of corns, and those of other graminea ; 2. in the round perennial tap roots, which shoot np an annual stem ; in the tuberose roots, such as potatoes, the Convolvulus batatas and edulitfihe HeliatUhus ivherosus, the Jatropha tnanihot, &c., which contain a great quantity of it ; 3. in the stems of several monocotyledinous plants, especially of the palm tribe, whence sago comes ; but it is very rarely found in the stems and branches of the dicotyledinous plants; 4. it occurs in many species of lichen. Three kinds of starch have been distinguished by chemists ; that of wheat, that called inuline, and lichen starch. These three agree in being insoluble in cold water, alcohol, ether, and oils, and in being converted into sugar by either dilute sulphuric acid or diastase. The main difference between (hem consists in their habitudes with water and iodine. The first forms with hot water a mucilaginous solution, which constitutes, when cold, the paste of the laundress, and is tinged blue by iodine; the second forms a granular precipitate, when its solution in boiling-hot water issuflered to cool, which is tinged yellow by iodine; the third affords, by cooling the concentrated solution, a gelatinous mass, with a clear liquoi floating over it, that contains little starch. Its jelly becomes brown-gray with iwJine. 1. Ordinary starch. — This may be extracted from the following grains : — wheat, rve^ 712 STARCH. l».rlpv oftts buckwheat, rice, maize, miUet, spelt ; from the siliquosc seeds, as peas beans, S^fle's Ic' ^STtuSeVous knd taproots, as those of the potato, the orchis, manioc, arrojjr «St bimti ic. Different kinds of corn yield very variable quantities of starch* Wh^aSe/s 1^ ihis respect, according to the varieties of the plant, as well as the soil '^z:Lrp^;^^:!T^ ^,-p^r' Sid\tTavr fiicture of starch, as this constituent suffers less injury than the gluten ; and it may be ^f '^l'::XS''Z^^^^^^^ siAed clean, is to be put into cistern^ eovered with soft water, and left to steep till it becomes swollen and so soft as to be Slfly crushed between Jhe fingers. It is now to be taken out, and ""«^^«^^ - ^ ^^ water of a temperature equal to that of malting-barley, whence it is to be transferred Jto Lgs. whXare placed in a wooden chest containing so.e water, and exposed to Srono^prersure. The water rendered milky by the starch being drawn off by a ap, feshwaler I poured in, and the pressure is repeated. Instead of putting the swollen «^iT»rnto bairsome prefer to griid it under vertical edge-stones, or between a pair of &ntal roflers, and'then to lly it in a cistern and separate the ^tarchj liqj^^^^^^^^ triation with successive quantities of water well stirred up with it. Ihe '^f »d"*7 "">^ iS- n the sacks or cisterns contains much vegetable albumen and gluten, along with the husS; when exposed to fermentation, it affords a small quantity of starch of rather in- '^ Th^abovImiJky liquor, obtained by expression or elutriation, is run into large CKtem^s where it deposits stanch in layers successively less and less dense; the upperm^t Iwitalnine a considerable proportion of gluten. The supernatant liquor being drawn X aid fresh water poured oi it, the whole must be well str red up allowed again to ^ttle and the surface- liquor again withdrawn. This washing should be repeated as toie as the watef takes any perceptible color. As the first turbid liquor contains a Sture of gluten, suRar! gum, albumen, &c., it ferments readily, and produces a certain Sn of finS^^ to dissolve out the rest of the mingled gluten, and thu. S?bWh the starch It is, in fact, by the action of this fermented or soured water, and Ltted wasS^^^^^^^^^ After the last deposition and decantation there Ip^^ars on the surface of the starch a thin layer of a slimy mixture of gluten and albu- me^ which being scraped off, serves for feeding pigs or oxen ; underneath will be found Tsurlh of goS quality Th^ layers of different sorts are then taken up with a wooden Jhovel tmnsfe^^ into separate cisterns, where they are agitated with water and passed Srough fine s Jv^^ After this pap is once more well settled, the clear water is drawn Sff the stLchy m^^^ is taken out, and laid on linen cloths in wicker baskets, to drain and Seiome partially dry. When sufficiently firm, it is cut nto pieces, which are spread upon other cloths, and thoroughly desiccated in a proper drying-room, which in winter is heat. Sbv stoves The upper surface of the starch is generally scraped, o remove any fusty' matler and the Resulting powder is sold in that state. , Wheat yields upon an average, only from 35 to 40 per cent, of good starch. It should afford more by skilful "Tirthil'country, wheat crushed between iron rollers is laid to steep in as much water as will wet it 'thoroughly ; in four or five days the mixture ferments, soon afterwards IS ties a^d sTeady to be washed out with a quantity of water into the proper ferment- Sgvas The common time allowed for the steep, is from 14 to 20 days The nex SIcess consists in removing the .stuff from the vats into a ^tout round basket set Lross a back below a pump. One or two men keep going round the bask e stirring up the stuff with strong wooden shovels, while another keeps P^^^J^.'^g J^^^V^'?/" /ij firina is completely washed from the bran. Whenever the subjacent t>ack is fille^ the liquor is taken out and strained through hair sieves into square frames or m^ni^ where it is allowed to settle for 24 hours; after which ^^^^ wa^er is run off from^^^^^ deposited starch by plug taps at different levels m the side. The thin stuff called ,^^". IZn the surface of the starch, is removed by a tray of a peculiar form. Fresh water is now introduced, and the whole being well mixed by proper agitation, is then poured npon fine silk sieves. What passes through is allowed to settle for 24 hours; the liquor being withdrawn, and then the slimes, as before, more water *« «f '" J/ff^ "' with agitatfon, when the mixture is again thrown upon the silk sieve. The milky liquor I now suffered to rest for several days, 4 or 5, till the starch becomes settled pretty firmly at the bottom of the square cistern. If the starch is to have the blue tint, called Poland, fine smalt must be mixed in the liquor of the last sieve, in the proportion of two or three pounds to the cwt. A considerable portion of these shnes may, by good manao^ement, be worked up into starch by elutriation and straining. The starch is now fit for fcoxrng, by shovelling the cleaned deposite into wooden chests. STARCH. 713 about 4 feet long, 12 inches broad, and 6 inches deep, perforated throughout, and lined with Ihin canvass. When it is drained and dried into a compact mass, it is turned out by inverting the chests upon a clean table, where it is broken into pieces four or five inches square, by laying a ruler underneath the cake, and giving its surface a cut with a knife, after which the slightest pressure with the hand will make the fracture. These pieces are set upon half-burned bricks, which by their porous capillarity imbibe the moisture of the starch, so that its under surface may not become hard and horny. When sufficiently dried upon the bricks, it is put into a stove, (which resembles that of a sugar refinery,) and left there till tolerably dry. It is now removed to a table, when all the sides are carefully scraped with a knife ; it is next packed up in the papers in which it is sold ; these packages are returned into the stove, and subjected to a gentle heat during some days ; a point which requires to be skilfully regulated. Mr. Samuel Hall obtained a patent for bleaching starch by chloride of lime in 1821. Chlorine water would probably be preferable, and might prove useful in operating upon damaged wheat. The sour water of the starch manufacture contains, according to Vauquelin, acetic acid, acetate of ammonia, alcohol, phosphate of lime, and gluten. During the drying, starch splits into small prismatic columns, of considerable regulari- ty. When kept dry, it remains unaltered for a very long period. When it is heated to a certain decree in water, the envelopes of its spheroidal particler burst, and the farina forms a mucilaginous emulsion, magma, or paste. When this apparent solution is eva- porated to dryness, a brittle horny-looking substance is obtained, quite different in aspect from starch, but similar in chemical habitudes. When the moist paste is exposed for two or three months to the air in summer, the starch is converted into sugar to the amount of one third or one half of its weight, into gum, and gelatinous starch called amidine by De Saussure, with occasionally a resinous matter. This curious change goes on even in close vessels. Starch from poiatoes.-^From the following table of analyses, it appears that potatoes contain from 24 to 30 per cent, of dry substance : — Red potatoes, - Germinating potatoes, - Kidney potatoes. Large red potatoes, Sweet potatoes, Peruvian potatoes, English potatoes, Parisian potatoes. fitow^Vi Fihrons Pa- Vegetable renchyma. Albumen 150 7-0 1-4 15-2 6-8 1-3 9-1 8-8 0-8 12-9 6-0 0-7 15-1 8-2 0-8 150 5-2 1-9 12-9 6-8 M 13-3 6-8 0-9 Gum, Sui^ar, and Salts. Water 9-2 75-0 3-7 730 — 81-3 — 780 — 74-3 1-9 760 1-7 77-5 4-8 73-1 Manufacture of potato starch.— The potatoes are first washed in a cylindrical cage formed of wooden spars, made to revolve upon a horizontal axis, in a trough fiJled with water to the level of the axis. They are then reduced to a pulp by a rasping machine similar to that represented in Jigs. 1047, 1048, where a is a wooden drum covered with sheet-iron, roughened outside with numerous prominences, made by punching out holes from the opposite side. It is turned by a winch fixed upon each end of the shaft. The drum is enclosed in a square wooden box, to prevent the potato-mash from being scatter- cd alwut. The hopper b is attached to the upper frame, has its bottom concentric with the rasp-drum, and nearly in contact with it. The pulp chest c is made to slide out, so as when full to be readily replaced by another. The two slanting boards d, d, conduct 'the pulp into it. A moderate stream of water should be made to play into the hopper upon the potatoes, to prevent the surface of the rasp from getting foul with fibrous matter. Two men, with one for a relay, will rasp, with such a machine, from 2* to 3 tons of po- tatoes in 12 hours. ^^ The potato pulp must be now elutriated upon a fine wire or hair seive, which is set npon a frame in the mouth of a large vat, while water is made to flow upon it from a spout with many jets. The pulp meanwhile must be stirred and kneaded by the hand, or by a mechanical brush-agitator, till almost nothing but fibrous particles are left upon the sieve. These, however, generally retain about five per cent, of starch, which cannot be separated in this way. This parenchyma should therefore be subjected to a separate rasping upon another cylinder. The water turbid with starch is allowed to settle for some time in a back ; the supernatant liquor is then run bj a cock into a second back, and aftef it 714 STARCH. 1349 1350 some time into a tnird, whereby the whole starch will be precipitated. The finest powder collects in the last vessel. The starch thus obtained, containing 33 per cent, of water, may be used either in th« moist state, under the name of green /eat- la, for various purposes, as for the prepa- ration of dextrine, and starch sirup ; or it may be preserved under a thin layer of water, which must be renewed from time to time, to prevent fermentation ; or last- ly, it may be taken out and dried. In trials made with St. Etienne's rasp and starch machinery, in Paris, which was driven by two horses, nearly 18 cwtg. of potatoes were put through all the re- quisite operations in one hour, including the pumping of the water. The product in starch amounted to from 17 to 18 per cent, of the potatoes. The quicker the process of potato-starch making, the bet- ter is its quality. Starch from certain foreign plants.--l. From the pith of the sago palm. See Saoo. 2 From Xe roots of the Maranta arundinacea, of Jamaica the Bahamas, and other wSt IndS islands, the powder called arrow-root is obtained, by a process analogous to '^'i'YZ^^r^^'^T Manioc, ^l^^^ also grows in the West Indies as well as in Africa, Te cLava is procured by i similar process. The juice of this plant is poison- ^s f^om whTch the wholesome starch is deposited. When dried with stirrmg upon hot Ton Dlales it a-glomerates into small lumps, called tapioca ; being a gummy fecula. Z characters of the different varieties of starch can be learned only from microscopic observation; by which means also their sophistication or admixture maybe readily as- ^^sStfrom whatever source obtained, is a white soft po^^er, which feels crispy, like flowe s of sXhur, when pressed between the fingers; it is destitute of taste and smell, nndian-eable in the atmosphere, and has a specific gravity of 1-53. I have already de- wr'bed'the particles as spheroid^ enclosed in a membrane. The potato contains some of he lar'e^st, and the millet the smallest. Potato starch consists of truncated ovoids^ rai^lngln'siz^from^ to^V^ofaninch; arrow-root, of ovoids varying m size from 1 to J— of an i2; flowerstarch, of insulated globules about ^^o «" "^ '"'^' ea^ava ^'^simular globules assembled in groups. These measurements I have made ^trrioodTCmftic microscope, and a divided glass-slip micrometer of TuUy For the saccharine changes which starch undergoes by the action oMiastase, see Fer- ■^^.S; a species of starch obtained ^^om Iceland moss, (Ce/rarm^^^^^^^^ as in-line, from elecampane, (Inula Helmium,) are rather objects of chemical curiosity, "^ T^lTalTnd o7;tarch made in order to be converted into gum for the calico-printer. This conversion having been first made upon the great scale in this country, has occa- sioied the pr^uct to be called British gum. The following is the process pursued m • Trge and wdl conducted establishment near Manchester. A range of four wooden cis- SrSs each about 7 or 8 feet square, and 4 feet deep, is provided. Into each of them 2000 gallons of waTer being introduced, 12i loads of flour are stirred in. This mixture is set to ferment upon old leaven left at the bottom of the backs, during 2 or 3 days. Thj intents are?hen stirred up, and pumped off into 3 stone cisterns 7 feet square and 4 feet deep ; as much water being added, with agitation, as will fill the cisterns to the brim. In the course of 24 hours the starch forms a firm depos.te at the bottom ; and the water is then svphoned off. The gluten is next scraped from the surface and the starch if transferred into wooden boxes pierced with holes, which may be lined with coarse cloth, or not, at the pleasure of the operator. ^ .* j • „ i„«i,- The starch, cut into cubical masses, is put into iron trays, and set to dry m a large apartment, two stories high, heated by a horizontal cylinder of cast iron traversed by he flame of a furnace. The drying occupies two days. It is now ready for eonvers ja fnto -urn for which purpose it is put into oblong trays of sheet iron, and heated to the lemperrii e of 300° F. in a cast-iron oven, which holds four of these trays. Here ,t Srete«r^nto irregular semi-transparent yellow-brown lumps, which are ground into fiTfloTr between mill stones, and in this state brought to the market ^n this roasted starch, tbe vesicles being burst, their contents become soluble m cold water, iiritiali STARCH. 716 ^m is not convertible into sugar, as starch is, by the action of dilute sulphuric acid ; oor into mucic acid, hj nitric acid ; but into the oxalic ; and it is tinged purple-red by iodine. It is composed, m 100 parts, of 35*7 carbon, 6'2 hydrogen, and 58*1 oxygen; while starch is composed of, 43'5 carbon, 6-8 hydrogen, and 49'7 oxygen. To prove whether starch be quite free from gluten, or whether it be mixed with any wheat flour, diffuse 12 grains of it through six ounces of water, heat the mixture to boiling, stirring it meanwhile with a glass slip. If the starch be pure, no froth will be seen upon the surface of the pasty fluid ; or if any be produced during the stirring, it will immediately subside after it ; but if the smallest portion of gluten be present, much froth will be permanently formed, which may be raised by stirring into the appearance of soap-suds. Starch has been made the subject of a patent by Mr. Thomas Berger, of Hack- ney, under which he soaks rice in caustic alkali, as Mr. Wickham did in 1824, at successive times, levigates it into a cream, adds one part of oil of turpentine to 2000 gallons of the cold mash, stirs the mixture, filters or strains through fine lawn sieves, settles, neutralizes with dilute sulphuric acid, and adding 8 oz, of sulphate of zinc to each cwt. of starch, stirs, boxes, and finishes as usual. One is apt to ask what purpose the spirits of turpentine can serve in such a small quantity, except it be to prevent ferment- ation. He also suggests electricity ; but how to use it he says not. In June, 1841, Mr. W. T. Berger obtained a patent for manufacturing starch by the agency of an alkaline salt upon rice. He prefers the carbonates of potash and soda. In January, 1839, M. Pierre Isidore Verdure obtained a patent for making starch, the chief object of which was to obtain the gluten of the wheat in a pure state, as a suitable ingredient in making bread, biscuits, *" ^^"* 206^0, and in this fondition H remains, undergoing slow evaporation, until the metal becomes so far cooled as to admit of the water coming into contact with it; when this occurs, the water loses its sphericJ ircoZct ZVr '^' TT'^'A'- ''''' "'^'^^ ^^^*^^ -^*^1' with which Tnowt m contact, and it is instantly dissipated m vapour. ««i^ ^rf 'l?'''^^^^ interesting experiments have been made in connection with this cL^^of LL^r'r^' ^"^,n*^' '''''^1' ^r ^^^" f«""^^ «" explanatio^of thai W- T/k^ kJ^P^"''?'. '""^'^^ ""T' "^^' b»^ not «' '^ ^om^nt of, the excessive heatmg of the boiler. It is assumed that in these cases the boiler becomes heated to a temperature at which the water is thrown into the spherical condl^Twhile in this s^a every lit le steam IS generated but as soon as the'^boiler has cooled to a p^"nt at Txpltr ^ "'"' '^' '"^^'" ^"'"^"'^"^ "^ " ^*^S« ^^^""^^ of steam caS the It has been found that other volatile bodies besides water are similarlv affected under like circumstances. Thus, ether, alcohol, iodine, 'lecting t^he^ro^luTin a sn«U tube sealed at one end, also surrounded with a freeyinir m.'vfnri ThL i:^.,!^ !i »lph«rous acid Ms at 14= Fahr and therefore. iHtTS T^ Ja "v iZt^t time the mouth of the tube must be sealed at the blowpipe flame. '^A thick platinum ^S .l^^JT?- "fT'^?^''"'" '?i .'' *° ^ '■««'«'? ^ redness, and whil^ in thU •t.te, about f 5 J of the sulphurous acd is to be rapidly projected out of the tube into 720 STEARIC ACID. \ 5 the crucible. The add assumes the spherical condition, and while in this state undergoes comparatively slow evaporation ; the lamp is now quickly withdrawn, and a small quan- tity of water thrown into the crucible with a syringe. The temperature of the crucible is reduced by the introduction of the water, so as to cause the contact, and conseauently .he instantaneous vaporization, of the sulphurous acid, which during its evaponzatioo, robs the water of its heat and reduces it to the state of ice. STEARIC ACID, improperly called Stearine {Talgsaure, Germ.), is the solid con- stituent of fatty substances, as of tallow and olive oil, converted into a crystalline mass by saponification with alkaline matter, and abstraction of the alkali by an acid. By this process, fats are convertible into three acids, called Stearic, Margaric, and Oleic ; the first two being solid, and the last liquid. The stearine, of which factitious wax candles are made, consists of the stearic and margaric acids combined. These can be separated from each other only by the agency of alcohol, which holds the margaric acid in solution after it has deposited the stearic in crystals. Pure stearic acid is prepared, according to its discoverer, Chevreul, in the following way : — Make a soap, by boiling a solution of potash and mutton-suet in the proper equivalent proportions (see Soap); dissolve one part of that soap in 6 parts of hot water, then add to the solution 40 or 50 parts of cold water, and set the whole into a place whose temperature is about 52" Fahrenheit. A substance falls to the bottom, possessed of pearly lustre, consisting of the bi-stearate and bi-margarate of potash ; which is to be drained and washed upon a filter. The filtered liquor is to be evaporated, and mixed with the small quantity of acid necessary to saturate the alkali left free by the precipitation of the above bi-salts. On adding water to it afterwards, the liquor aflTords a fresh quantity of bi-stearate and bi-margarate. By repeating this operation with precaution, we finally arrive at a point when the solution contains no more of these solid acids, but only the oleic. The pre- cipitated bi-salts are to be washed and dissolved in hot alcohol, of specific gravity 0*820, of which they require about 24 times their weight. During the cooling of the solution, the bi-stearate falls down, while the greater part of the bi-margarate, and the remainder of the oleate, remain dissolved. By once more dissolving in alcohol, and cr^^stallizing, the bi-stearate will be obtained alone ; as may be proved by decomposing a little of it in water at a boiling heat, with muriatic acid, letting it cool, washing the stearic acid obtained, and exposing it to heat, when, if pure, it will not fuse in water under the 158th degree of Fahrenheit's scale. If it melts at a lower heat, it contains more or less mar- garic acid. The purified bi-stearate being decomposed by boiling in water along with any apid, as the muriatic, the disengaged stearic acid is to be washed by melting in water, then cooled and dried. Stearic acid, prepared by the above process, contains combined water, from which it cannot be freed. It is insipid and inodorous. After being melted by heat, it solidifies at the temperature of 158° Fahrenheit, and affects the form of white brilliant needles grouped together. It is insoluble in water, but dissolves in all proportions in boiling anhydrous alcohol, and on cooling to 122°, crystallizes therefrom, in pearly plates; but if the concentrated solution be quickly cooled to 112°, it forms a crystalline mass. A dilute solution affords the acid crystallized in large white brilliant scales. It di». solves in its own weight of boiling ether of 0'727, and crystallizes on cooling in beau- tiful scales, of changing colors. It distils over in vacuo without alteration ; but if the retort contains a little atmospheric air, a small portion of the acid is decomposed during the distillation; while the greater part passes over unchanged, but slightly tinged brown, and mixed with traces of empyreumalic oil. When heated in the open air, and kindled, stearic acid burns like wax. It contains 3*4 per cent, of water, from which it may be freed by combining it with oxyde of lead. When this anhydrous acid is sub- jected to ultimate analysis, it is found to consist of — 80 of carbon, 12-5 hydrogen, and 7-5 oxygen, in 100 parts. Stearic acid displaces, at a boiling heat in water, carbonic acid from its combinations with the bases ; but in operating upon an alka- line carbonate, a portion of the stearic acid is dissolved in the liquor before the carbonic acid is expelled. This decomposition is founded upon the principle, that the stearic acid transforms the salt into a bicarbonate, which is decomposed by the ebullition. Stearic acid put into a strong watery infusion of litmus, has no action upon it in the cold ; but when hot, the acid combines with the alkali of the litmus, and changes its blue color to red ; so that it has sufficient energy to abstract from the concentrated tincture all the alkali required for its neutralization. If we dissolve bi-stearate of potash in weak alcohol, and pour litmus water, drop by drop, into the solution, this will become red, because the litmus will give up its alkali to a portion of the bi-stearate, and will con- vert it into neutral stearate. If we now add cold water, the reddened mixture will re- sume its blue tint, and will deposite bi-stearate of potash in small spangles. In order that the alcoholic solution of th^ bi-stearate may redden the litmus, the alcohol should not be very strong. m STEARINE COLD PRESS. 721 From the composition of stearate of potash, the atomic weight of the acid appears to be 106-6 ; hydrogen being 1 ; for 18 : 48 X 2 :: 100 : 533-3 = 5 atoms of acid. From the stearate of soda, it appears to be 104 ; and from that of lime, 102. The stearate of lead, by Chevreul, gives 109 for the atomic weight of the acid. The margaric and oleic acids seem to have the same neutralizing power, and the same atomic weight. The preceding numbers will serve to regulate the manufacture of aCearic acid for the purpose of makin? candles. Potash and soda were first prescribed for saponifying fat, as may be seen in M. Gay Lussac's patent, under the article Candle ; and were it not for the cost of these articles, they are undoubtedly preferable to all others in a chemical point of view. Of late years lime has been had recourse to, with perfect success, and has be- come subservient to a great improvement in candle-making. The stearine block now made by many London houses, though containing not more than 2 or 3 per cent, of wax, is hardly to be distinguished from the purified produce of the bee. The first process is to bod the fat with quicklime and water in a large tub, by means of perforated steam pipes distributed over its bottom. From the above statements we see that about 11 parts of dry lime are fully equivalent to 100 of stearine and oleine mixed : but as the lime is in the state of hydrate, 14 parts of it will be required when it is perfectly pure; in the ordi- nary state, however, as made from average good limestone, 16 parts may be allowed. After a vigorous ebullition of 3 or 4 hours, the combination is pretty complete. The stearate being allowed to cool to such a degree as to allow of its being handled, becomes a coricrete mass, which must be dug out with a spade, and transferred into a contiguous tub, m order to be decomposed with the equivalent quantity of sulphuric acid diluted With water, and also heated with steam. Four parts of concentrated acid will be sufll- cient to neutralize three parts of slaked lime. The saponified fat now liberated from the hme, which is thrown down to the bottom of the tub in the state of sulphate, is skimmed off the surface of the watery menstruum into a third contiguous tub, where it is washed with water and steam. The washed mixture of stearic, margaric, and oleic acids, is next cooled in tin pans ; then shaved by large knives, fixed on the face of a fly-wheel, called a tallow cutter, pre- paratory to its being subjected in canvass or caya bags to the action of a powerful hydrau- lic press. Here a large portion of the oleic acid is expelled, carrying with it a little of the margaric. The pressed cakes are now subjected to the action of water and steam once more, after which the supernatant stearic acid is run off, and cooled in moulds. The cakes are then ground by a rotatory rasping-machine to a sort of mealy powder, which is put into canvass bags, and subjected to the joint action of steam and pressure in a hori- zontal hydraulic press of a peculiar construction, somewhat similar to that which has been long used in London for pressing spermaceti. The cakes of stearic acid thus freed completely from the margaric and oleic acids, are subjected to a final cleansing in a tub with steam, and then melted into hemispherical masses called blocks. When these blocks are broken, they display a highly crystalline texture, which would render them unfit for making candles. This texture is therefore broken down or comminuted by fusin<' the stearme in a plated copper pan, along with one thousandth part of pulverized arsenious *"oJ.^ » i^rTJii^^^'^ '^ ^^^^^' *° ^^ '^^^^ '"^o candles in appropriate moulds. See Candlk. SrEARINE COLD PRESS. The cold hydraulic press, as mounted by Messrs. Maudslay and Fm^, for squeezing out the oleic acid from saponified fat, or the oleine Scale Z-1QtKs of an inch to the foot. 1354 -722 STEARINE COLD PRESS. »l 1355 Uuuuuiuy frwn 4x>coa-nut lard, is represented in plan in fig. 1854. ; in side viexr of pump in fi^. 1355. ; and in elevation, /^r. 1356. ; where the same letters refer to like objects. A, L, are two hydraulic presses ; b, the frame ; c, the cylinder ; d, the piston or ram ; K, the follower ; f, the recess in the bottom to receive the oil ; g, twilled woollen bags ; with the material to be pressed, having a thin plate of wrought iron between each ; h, apertures for the discharge of the oil ; i, cistern in which the pumps are fixed ; k, fram- ing for machinery to work in; l, two pumps, large and small, to inject the water into the cylinders ; m, a frame con- taining three double branches; n, three branches, each having two stops or plugs, by which the ac- tion of one of the pumps may be intercepted from, or communicated to, one or both of the presses ; the large pump is worked at the be- ginning of the operation, and the small one towards the end; by these branches, one or both presses may be discharged when the opera- tion is finished ; o, two pipes from the pumps to the branches ; p, pipe to return the water from the cyhn- ders to the cisterns ; q, pipes lead- ing from the pumps through the branches to the cylinders; e, coni- cal drum, fixed upon the main shaft ] Y, driven by the steam-engine of the factory ; s, a like conic^ drum to work the pumps ; t, a narrow leather strap to communicate the motion from r to s ; u, a long screw bearing a nut, which works along the whole length of the drum ; v, the fork or guide for moving the strap t ; w, w, two hanging bearings to carry the drum s; X, a pulley on the spindle of the drum s ; y, the main shaft ; z, fly-wheel with groove on the edge, driven by the pulley x ; on the axis of s, is a double crank, which works the two pumps L. a, is a pulley on the end of the long screw u ; an endless cord passes twice round this pulley, and under a pulley fixed in the weight h ; by layiiig hold of both sides of this cord, and raising or lowering it, the forked guide v, and the lea- ther strap T, are moved backwards or forwards, by means of the nut fixed in the guide, 80 as to accelerate or retard at pleasure the speed of the working of the pumps ; c, is a piece of iron, with a long slit, in which a pin, attached to Uie fork v travels, to keep it in the vertical position. STEATITE. 723 STEARINE. Fig 1367. is a view of both the exterior and interior of the saponi- iii\\v 1^7 u ^ng tun of a stearine factory; where the constituents of the tallow are combined with juicklime, by the intervention of water and steam: a, is the upriSt shSK i^n nimed by tiie bevel wheel above, in gear with anoth in Shetland, in the limestone of Icolmkiln, in the serpentine of CornwaU, in Anglesey ji .am It makes the buiscuit semi-transparent, but rather brjtle, and ant to crack with slight changes of heat. It is employed for polishing serpentine, marble^gVisers alalas^ ter, and mirror glass ; as the basis of cosmetic powders ; as an inoredient [rant attrition pastes; it is dusted in powder upon the inside of boots, 'to mak^ttfeet gHde e^^^^^^^^^^^^ them; when rubbed upon grease-spots in silk and wooUen clothes, it renfoves the stains by absorption ; it enters into the composition of certain crayons, andT used Use^ for making traces upon glass, silk, &c. The spotted steatite, cut into'cameos and ^alc ned assumes an onyx aspect. Soft steatite forms exceUent stoppers for the chemical apDam ST'i?rr.^i'''^^'"# «^ «"Wiming corrosive vapors. Lamellar steatite is Talc ^"^ bTEEL (^cier, Fr. ; Stahl, Germ.), as a carburet of iron, has already been considered "ch^ical rS:lts.' '''" '"'' " ''" "^^^^^ "^" '"^'''^^''^ '' ''' manXrre ani 1. Steel of cemmtation, bar or blistered steel.-With the exception of the Ulverstone charcoal iron, no bars are manufactured in Great Britain capable of conversion inti steel at all approaching m quality to that made from the Madras, Swedish, and Russian irons so largely imported for that purpose. The first rank is assigned to the SwXh Tron W^of Z m''"^^ f"'^°'V"? '^' ^''''' ^ (^^"^^^ ^«"^d hoopl) ; which fetches he igS Sp nriL T>?/- r T' J^u^- '^''"'"* ^""^^''^ ^^^^'^^^'^ "^^^ ^e had for one fifth of mZr ; A- ?i*'^' ^"^^^''^ ''^"Z ^'^ '^^'^ ^* ^ "^"<=^ l«^er rate, though said to be manufactured m the same way ; and therefore the superiority of the Dannemora iron must be owing to some peculiarity m the ore from which it is smelted. The steel recentlv Som tie ""' '''''■"'''' '^ '^'''^^^' ^''"^ '''' «^^^^'« Madras iron, rivals^^^^^^^^ The Sheffield furnace for making bar or blistered steel, called the furnace of cementa- Uon, IS represented m ^g. 1359, in a cross section, and in Jig. laeo, in a ground pkS. 1J^59 . 1360 STEEL. 725 Of chimnev from ?ft *„ Kn^Tu°u t °. ,?"™«e »« b"il' under a conical hood amoke ^' ^^ *° ^^ ^'" ''«'•• f"' ^^^ the draught, and carrying off the The two chests are built of fire-stone grit. Thev are 8 1ft a, •„=„ i k <• . i j from 26 to 36 inches in wi<1th ..n^ j.^fi, \\. V ' ', • *" *'^^° '* '^et long, and uniform will the quali? rf tte 8?eel l£ 'a * 'Tk '^i^Y' ^'^ "«• "'«""'" incompaUble withlqSlUy of'th tm'^ntint ^^'"T^^^^, ^fs"" "' V""^' T thick. The space teween them is at lo»f» - r? • j ""1 '""'" "^ * ^^"^ '""=''«' directly upon the sole of the ZJLf w " ?l' '"<'*■ ^'7 «'«»'W "«''"• "-es' upon gy tL arme,^ weU L [^^^3 a^n"^"'' ^^^ ^Y" '""'>'° f'^^'? P'*?"! bropenings in the Mcror^non lh» fn^ jP" A* •''K'*^ "' •"'»' » regula'ted PoillKiv »h?c 'u *''*'*'""^ ?^.i^^ ""^P^"*"* ^^'^'^^^ »"^ <^^ay, which it penerally contains. Possibly the salt serves to vitrify the particles of silica in the charcoa"], and thus to pre- df^ni^r Y^ ""^ *"JSu ^r^'"**^''" ^'^^ ^^^ ^t^^'- As for the ashes, it is difficult to discover their use. The best steel may be made without their presence. The bottom of lill^"^-^ " T^""^ ^'"^^^ t^« ^"<^*^^« ^^t'^e PO^vder of cementation, the bars are laid ^ic^r" V"^" their narrow edge, the side bar being one inch from the trough, and the Zl Zl IZ '"' ^'f.'" 'u''; ?"^'^' ^^ ^" ^"^^ ^P*^^- A^«^e this first layer of iron bars, fully half an inch depth of the powder is spread, then a new series of bars is strali- fin^^ w;t1? n?^ ^ ?'*""\'' ^"^'i '^'^^''^ '^'^ ^"'^^^ °^ the top. This space is partially filled with old cement powder, and is covered with refractory damp sand. Sometimes nL t\ 't l.*^^^^ '"'^^'^^ "^"h the old cement, and then closely covered with fire- uies. Ihe bars should never be allowed to touch each other, or the trough. The A-e ?or? w^'^' ""/ "^^i ^'^"^ \;^° *^ ^°"' ^^^^^ *tH it acquires the temperature ^f 100«Wedgewood; which must be steadily maintained during the four, six, eight oi ten days requisite for the cementation ; a period dependant on the size of the furnace, and which is determined by the examination of the proof pieces, taken out from time to In the front or remote end of the furnace,./Zg. 1054, a door is left in the outer buildin.^, corresponding to a similar one in the end of the interior vault, through which the work! man enters for charging the furnace with charcoal and iron bars, as also for taking out the steel after the conversion. Small openings are likewise .-sde in the ends of the chests, through which the extremities of a few bars are left projecting, so that thev raav be pulled out and examined, through small doors opposite to them in the exterior wail/. These tap holes, as they are called, ohould be placed near the centre of the end stones of the chests, that the bars may indicate the average state of the process. The joiain'-s of the fire-stones are secured with a finely ground Stourbridge clay "* The interval between the two chests (in furnaces containing 'two, for many have only one) being covered with an iron platform, the workman stands on it, and sifts a layer of charcoal on the bottom of the chests evenly, about half an inch thick; he then lays a row of bars, cut to the proper length, over the charcoal, about an inch from each other- he next sifts on a second stratum of charcoal-dust, which, as it must serve for the bars abive, fi?i^ SK-^ '• '"u^^'^r T '"''^ ^^'f 5 thus, he continues to stratify, till the chest be f f^ J!^."" ^"^^ '"^^^' ""^ ^^^ ^""P ' *"^ ^^ '^"^^'■^ the whole with the earthy detritus found at the bottom of grindstone troughs, or any convenient fire-loam. It is obvious that the second series of bars should correspond vertically with the interstices between the first senes, and so m succession. The trial-rods are left longer than the others, and their projecting ends are incrusted with fire-clay, or imbedded in sand. The iron platform being removed, and all the openmgs into the vault closed, the fire is lighted, and very gradually increased to avoid every risk of cracking the grit-stone bv too sudden a chan4 ol temperature; and the ignition being finally raised to about JOO^'Wedgewood, but not higher, for fear of melting the metal, must be maintained at a uniform pitch, till the iron have absorbed the desired quantity of carbon, and have been converted as highly as the manufacturer intends for his peculiar object. From six to eight days may be reckoned a sufficient period for the production of steel of moderate hardness, and fit for tUting into I^A T]\ ^ f'^'l''^}> ^- i^^« -»d «P"n?^. takes a shorter period and a ha Se? charcoal B^ItT^ '^r ''' "'^^ ^" "'^"^"! ^'■""' ^'" "^^^ ^""^^^ ^^P^^^^e to the ignuS charcoal But, for a few purposes, such as the bits for boring cast iron, the bar«; arc exposed o two or three successive processes of cementation, and are hence said to b^ twice or thrice converted into steels. The higher the heat of the furnace, the quicker i^ Uie process of conversion. ' quicucr is The furnaoe being suffered to cool, the workman enters it again, and hands out the steel bars, which being covered with blisters, from the formation and bursting of vesicles on the surface filled with gaseous carbon, is called bmered steel. This steel t veA irreeu^ lar m its interior texture has a white color, like frosted silver, and di 'plays cn'sta^fnc angles and facettes which are larger the further the cementation has been urgS or he fhTsurflc: ofThelT"^"- ^'^ ^^^^^'^ ^^^^^^^ ^^ ^'^^^^ -^"^r than fhte'nlL^ In such a furnace as the above, twelve tons of bar iron may be converted at a charge But other furnaces are constructed with one chest, which receives six or eight tons af a time ; the small furnaces, however, consume more fuel in proportion than the arger The absorption and action of the carbonaceous matter, to the amount of about a half per cent., occasions fissures and cavities in the substance of the blistered bTs whrch render the steel unfit for any useful purpose in tool-making, till it be cSsed a^Ire^^^^ foe'lRON!^'''"' ""^ "" "'^' ""'''' ^ P«^^r^«l h^'^nier driven by macMnerJ. * For minute details of the parts, aee the excellent article T.ltino-h^mm.r. in Ree,U Cyclop^i^ 726 STEEL. STEEL. 727 I i The heads of the iflt-hammers for steel weigh from one and a half to two hundred pounds. Those in the neighborhood of Sheffield are much simpler than the one referred to in the note. They are worked by a small water-wheel, on whose axis is another wheel, bearing a great number of cams or wipers on its circumference, which strike the tail of the hammer in rapid succession, raise its head, and then let it fall smartly on the hot metal rod, dexterously presented on its several parts to the anvil beneath it, by the workman. The machinery is adapted to produce from 300 to 400 blows per minute ; which on this plan requires an undue and wasteful velocity of the float-boards. Were an intermediate toothed wheel substituted between the water-wheel and the wiper- wheel, so that while the former made one turn, the latter might make three, a much smaller force of water would do the work. The anvils of the tilt-hammer are placed nearly on a level with the floor of the mill-house ; and the workman sits in a fosse, dug on purpose, in a direction perpendicular to the line of the helve, on a board suspended from the roof of the building by a couple of iron rods. On this swinging seat, he can advance or retire with the least impulse of his feet, pushing forward the steel bar, or drawing it back with equal rapidity and convenience. At a small distance from each tilt, stands the forge-hearth, for heating the steel. The bellows for blowing the fire are placed above-head, and are worked by a small crank fixed on the end of the axis of the wheel, the air being conveyed by a copper pipe down to the nozzle. Each workman at the tilt has two boys in attendance, to serve him with hot rods, and to take them away after they are hammered. In small rods, the bright ignition originally given at the forge soon declines to darkness; but the rapid impulsions of the tilt revive the redness again in all the points near the hammer ; so that the rod, skilfully handled by the workman, progressively ignites where it advances to the strokes. Personal inspection alone can communicate an adequate idea of the precision and cele- rity with which a rude steel rod is stretched and fashioned into an even, smooth, and sharp-edged prism, under the operation of the tilt-hammer. The heat may be clearly referred to the prodigious friction among the particles of so cohesive a metal, when they are made to slide so rapidly over each other in every direction during the elongation and squaring of the rod. 2. Shear steel derives its name from the accidental circumstance of the shears for dressing woollen cloth being usually forged from it. It is made by binding into a bundle, with a slender steel rod, four parallel bars of blistered steel, previously broken into lengths of about 18 inches, including a fifth of double length, whose projecting end may serve as a handle. This fagot, as it is called, is then heated in the forge-hearth to a good welding-heat, being sprinkled over with sand to form a protecting film of iron slag, carried forthwith to the tilt, and notched down on both sides to unite all the bars to- gether, and close up every internal flaw or fissure. The mass being again heated, and the binding rings knocked ofiT it, is drawn out into a uniform rod of the size required. Manufacturers of cutlery are in the habit of purchasing the blistered bars at the con- version furnaces, and sending them to tilt-mills to have them drawn out to the proper size, which is done at regular prices to the trade ; from 5 to 8 per cent, discount being allowed on the rude bars for waste in the tilting. The metal is rendered so compact by the welding and hammering, as to become susceptible of a much finer polish than blis- tered steel can take ; while the uniformity of its body, tenacity, and malleability are at the same time much increased ; by which properties it becomes well adapted for making table knives and powerful springs, such as those of gun-locks. The steel is also softened down by this process, probably from the expulsion of a portion of its carbon during the welding and subsequent heats ; and if these be frequently or awkwardly applied, it may pass back into common iron. 3. Cast steel is made by melting, in the best fire-clay crucibles, blistered steel, broken down into small pieces of convenient size for packing; and as some carbon is always dissipated in the fusion, a somewhat highly converted steel is used for this purpose. The furnace is a square prismatic cavity, lined with fire-bricks, 12 inches in each side, and 24 deep, with a flue immediately under the cover, 3| inches by 6, for conducting the smoke into an adjoining chimney of considerable height. In some establishments a dozen such furnaces are constructed in one or two ranges, their tops being on a level with the floor of -the laboratory, as in brass-foundries, for enabling the workmen more conveniently to inspect, and lift out, the crucibles with tongs. The ash-pits terminate in a subterraneous passage, which supplies the grate with a current of cool air, and serves for emptying out the ashes. The crucible stands, of course, on a sole piece of baked fire-clay; and its mouth is closed with a well-fitted lid. Sometimes a little bottle-glass, or blast-furnace slag, is put into the crucible, above the steel pieces, to form a vitreous coating, that may thoroughly exclude the air from oxidising the metal The fuel employed in the cast-steel furnace is a dense coke, brilliant and sonorous, broken into pieces about the size of an egg, one good charge of which is sufficient. The tongs are furnished at the fire end with a pair of concave jaws, for embracing the cttrvature of the crucible, and lifting it out whenever the fusion is complete. The lid is then lemoved, the slag or scoriae cleared away, and the liquid metal poured Into east-iron octagonal or rectangular moulds, during which it throws out brilliant scintil- lations. Cast-steel works much harder under the hammer than shear steel, and will not, in its usual state, bear much more than a cherrj-red heat without becoming brittle ; nor can it beeur the fatigue incident to the welding operation. It may, however, be firmly welded to iron, through the intervention of a thin film of vitreous boracic acid, at a moderate de- gree of ignition. Cast steel, indeed, made from a less carbureted bar steel, would be sus- ceptible of welding and hammering at a higher temperature ; but it would require a very high heat for its preparation in the crucible. Iron may be very elegantly plated with cast steel, by pouring the liquid metal from the crucible into a mould containing a bar of iron polished on one face. In this cir- cumstance the adhesion is so perfect as to admit of the two metals being rolled out to- gether ; and in this way the chisels of planes and other tools may be made, at a moderate rate and of excellent quality, the cutting-edge being formed in the steel side. Such instruments combine the toughness of iron with the hardness of steel. For correcting the too high carbonization of steel, or equalizing the too highly cott- verted exterior of a bar with the softer steel of the interior, the metal requires merely to be imbedded, at a cementing heat, in oxyde of iron or manganese ; the oxygen of whi^ soon abstracts the injurious excess of carbon, so that the outer layers may be even con- verted into soft iron, while the axis continues steely ; because the decarbonizing advancei far more rapidly than the carbonizing. Fig. 1361 represents the mould for making crucibles ior the cast-steel works, m bc, is a solid block of wood, to support the two-handled outside mould n, n. This being rammed full of the proper clay dough or compost (see Cbuci- ble), the inner mould is to be then pressed vertically ' into it, till it reaches the bottom f, being directed and facilitated in its descent by the point k. A cord passes through o, by which the inner mould is suspended over a pulley, and gviided in its motions. When a plate of polished steel is exposed to a progressive heat, it takes the following colors in succession : 1 , a faint yellow ; 2, a pale straw-color ; 3, a full yellow ; 4, a brown yellow ; 5, a brown with purple spots ; 6, a purple ; 7, a br^ht blue ; 8, a full blue ; 9, a dark blue, verging on black ; after which the approach to ignition supersedes all these colors. If the steel plate has been previously hardened by being dipped in cold water or mercury when red-hot, then those successive shades indicate or correspond to successive degrees of softening or tempering. Thus, No. 1 suits the hard temper of a lancet, which requires the finest edgCf but little strength of metal ; No. 2 a little softer, for razors and surgeons' ampu- tating instruments ; No. 3, somewhat more toughness, for penknives ; No. 4, for cold chisels and shears for cutting iron ; No. 5, for axes and plane-irons ; No. 6, for table knives and cloth shears ; No. 7, for swords and watch-springs ; No. 8, for small fine saws and diggers ; No. 9, for large saws, whose teeth need to be set with pliers, and sharpened with a file. After ignition, if the steel be very slowly cooled, it becomes exceedingly soft, and fit for the engraver's purposes. Hardened steel may be tempered to the desired pitch, by plungin? it in metallic baths heated to the proper thermometric degree, as fol- lows : for No. 1, 430° Fahr. ; No. 2, 450° ; No. 3, 470° ; No. 4, 490° ; No. 5, 510° j No, 6, 530° ; No. 7, 550°; No. 8, 560° ; No. 9, 600°. Small steel tools are most frequently tempered, after hardening, by covering their surface with a thin coat of tallow, and heating them in the flame of a candle till the tallow diffuses a faint smoke, and then thrusting them into the cold tallow. Rinman long ago defined steel to be any kind of iron which, when heated to redness, and then plung^ m cold water, becomes harder. But several kinds of cast iron are susceptible of such hardening. Every malleable and flexible iron, however, which may be hardened in that way is a steel. Moreover, steel may be distinguished from pure iron by its giving a dark-gray spot when a drop of dilute nitric acid is let fall on its surface, while iroi affords a green one. Exposed to the air, steel rusts less rapidly than iron ; and the more highly carbureted, the more slowly does it rust, and the blacker is the spot left bt an acid. After hardening, steel seems to be quite a diflTerent body; even its granular texture becomes coarser or finer, according to the degree of heat to which it was raised ; it grows so hard as to scratch gla$s, and resist the keenest file, while it turns exceedingly brittle. 728 STEEL. STEEL. 720 it i When a slowly cooled steel rod is forged and filed, it becomes capable of affording agreeable and harmonious sounds by its vibrations; but hard-tempered steel affordi only dull deafened tones, like those emitted by a cracked instrument The good quality of steel is shown by its being homogeneous ; being easily worked at the forge; by its hardening and tempering well; by its resisting or overcoming forces; and by its elasticity. To ascertain the first point, the surface should be ground and po- lished on the wheel ; when its lustre and texture will appear. The second test require? a skilful workman to give it a heat suitable to its nature and state of conversion. Th« size and color of the grain are best shown by taking a bar forged into a razor form ; har. dening and tempering it; and then breaking off the thin edge in successive bits with hammer and anvil. If it had been fully ignited only at the end, then, after the harden ing, it will display, on fracture, a succession in the aspect of its grains from that extra mity to the other; as they are whiter and larger at the former than the latter. The othei qualities become manifest on filing the steel; using it as a chisel for cutting iron; d bending it under a heavy weight. Much interest was excited a few years back by the experiments of Messrs. Stodart and Faraday on the alloys of steel with silver, platinum, rhodium, and iridium. Steel refusei to take up in fusion more than one five-hundredth part of silver; but with this minute quantity of alloy, it is said to bear a harder temper, without losing its tenacity. When pure iron is substituted for steel, the alloys so formed are much less subject to oxydation in damp air than before. With three per cent, of iridium and osmium, an alloy was ob- tained which had the property of tempering like steel, and of remaining clean and bright, in circumstances when simple iron became covered with rusi. »*Upon the whole," says the editor of the Quarterly Journal of Science, giving a report of these experiments in his 14th volume, p. 378, "though we consider these researches upon the alloys of steel as very interesting, we are not sanguine as to their important influence upon the improve- ment of the manufacture of cutlery, and suspect that a bar of the best ordinary steel, s©. lected with precaution, and most carefully forged, wrought, and tempered, under the im- mediate impedion of the master, would afford cutting instruments as perfect and excellent as those composed of wootz, or of the alloys." The patent plan of Mr. William Onions of making cast steel seems worthy of adop- tion. He takes two parts by weight of haematite ore (such as that of Cumberland) reduced to a state of coarse powder, and puts them into a crucible ; he then adds thereto four parts, by weight, of steel, made in the ordinary way, and ninety-four parts of iron, broken into small pieces, the iron used being that made from Cumber- land ore, or other iron which can be rendered malleable by annealing ; and he melts these materials together. Instead of first running the metal into ingots or bars, and then remelting it, he casts it at once in sand moulds, into the articles required to be formed of cast steel. These castings are rendered malleable by the process of anneal- ing, and may be tempered in the same way as articles made of ordinary steel. The annealing process employed is that by which castings of iron, made from Cumberland and like ores, are rendered malleable. The articles are put into pots or boxes with pulverized Cumberland ore, or other matter usually employed and subjected to heat, in an annealing oven, for a time dependent upon the thickness or substance of the articles, under treatment. The articles which are annealing at the same time should therefore be as nearly as possible of the same thickness; and the heat should not be permitted to increase rapidly, nor to attain too high a temperature. The time required for the an- nealing processes will be ascertained by practice. To anneal articles about an inch square (supposing the metal to be in bars of that thickness) they should be kept at a red heat for 120 hours; the time occupied in raising them to that heat should be 14 hours, and after they have been kept at a red heat for 10 hours, they should be allowed to cool down very gradually, say in not less than 24 hours. The articles thus annealed may be turned or otherwise reduced to the desired shape by the ordinary tools, and may be tempered in the same manner as articles made of common cast steel. The patentee does not confine himself to the above details; but he claims the mode of manufacturing cast-steel by melting matters together apd annealing the products, fts above described. Case-hardening of iron, is a process for converting a thin film of the outer surface into steel, while the interior remains as before. Fine keys are generally finished in this way. See Case-hardening. So great is the affinity of iron for carbon, that, in certain circumstances, it will absorb it from carburetted hydrogen, or coal-gas, and thus become converted into steel. On this principle, Mr. Mackintosh of Glasgow obtained a patent for making steel. His furnace consists of one cylinder of bricks built concentrically within another. The bars of iron are suspended in the innermost, from the top; a stream of purified coal-gas circulates freely round them, entering below and escaping slowly above, while the bars are main- tained in a state of bright ignition by a fire burning in the annular space between the cylinders. The steel so produced is of excellent quality; but the process does not seem to be so economical as the ordinary cementation with charcoal powder. Damasking of steel, is the art of giving to sabre blades a variety of figures in the stylf of watering. See Damascus Blades. Several explanations have been offered of the change in the constitution of steel, which accompanies the tempering operation ; but none of them seems quite satisfactory. It seems to be probable that the ultimate molecules are thrown by the sudden cooling into a constrained state, so that their poles are not allowed to take the position of strong* est attraction and greatest proximity ; and hence the mass becomes hard, brittle, and somewhat less dense. An analogous condition may be justly imputed to hastily cooled glass, which, like hardened steel, requires to be annealed by a sul^jequent nicely gradua- ted heat, under the influence of which the particles assume the position of repose, and constitute a denser, softer, and more tenacious body. The more sudden the cooling oi ignited steel, the more unnatural and constrained will be the distribution of its particles, and also the more refractory, an effect produced by plunging it into cold mercury. This excess of hardness is removed in any required degree by judicious annealing or temper* ing. The state of the carbon present in the steel may also be modified by the rate oj refrigeration, as Mr. Karslen and M. Breant conceive happens with cast iron and the damask metal. If the uniform distribution and combination of the carbon through the mass, determine the peculiarity of white cast iron, which is a hard and brittle substance and if its transition to the dark-gray and softer cast metal be effected by a partial form* tion of plumbago during slow cooling, why may not something similar be supposed to oc- cur with steel, an analogous compound ? Mr. Oldham, printing engineer of the Bank of England, who has had great experience in the treatment of steel for dies and mills, says that, for hardening it, the fire should never be heated above the redness of sealing-wax, and kept at that pitch for a sufficient time. On taking it out, he hardens it by plunging it, not in water, but in olive oil, o. rather naptha, previously heated to 200*^ F. It is kept immersed only till the ebullition ceases, then instantly transferred into cold spring water, and kept there till quite cold. By this treatment the tools come out perfectly clean, and as hard as it is possible to make cast-steel, while they are perfectly free from cracks, flaws, or twist. Large tools are readily brought down in temper by being suspended in the red-hot muffle till they show a straw color ; but for small tools, he prefers plunging them in the oil heated to 400 de- grees ; and leaves them in till they become cold. Mr. Oldham softens his steel dies by exposing them to ignition for rtie requisite time, imbedded in a nixture of chalk and charcoal. "The common mode of softening steel," says Mr. Baynes, "is to put it into an iron case, surrounded with a paste made of lime, cow's gall, and a little nitre and water; then to expose the case to a slow fire, which is gradually increased to a considerable heat, and afterwards allowed to go out, when the steel is found to be soft and ready for the engraver."* Steel, manufacture of. — Iron in the composition of which a portion of the silica is re- placed by manganese, will while being smelted rather part with the latter than the former. From this it follows, that at the moment when the iron is on the point of pass- ing from a liquid to a solid state it will retain sufficient silica to form steel. For this reason, during the whole process of refining, the current of air is caused to act rather upon the surface of the metal than through the interior of the fluid mass, in order to avoid the combustion of too much carbon and silica ; from which it follows that the casting becomes malleable without losing a suflScient quantity of silica to constitute iron, prop» erly so called, and the product is raw or blistered steel. The casting which does not contain any manganese loses by the effect of combustion a portion of silica proportion- able to the quantity of carbon burnt, and furnishes iron only as definite product It is simply to the mechanical action of the hammer, that the distinctive features of bar steel, as compared with that of cast steel, are due. In order to effect this change, the blistered steel is broken into pieces and melted down ; they are afterward tem- pered, again broken into pieces, and welded together at a good welding heat The steel will be the more malleable, and possesses more tenacity and uniformity of texture, in proportion to the number of times these operations are repeated. The product is called " wrought or shear steel." Steel of cementation and cant steel. — When bar iron is heated to a white heat, or even melted in close vessels containing coal or carbonaceous substances, it takes up a certain quantity of carbon, and is transformed into cast-steel of various kinds. If the iron contains together with silica, phosphorus and arsenic in proportions suit- * History of the Cotton Manufacture, p. 269. If that strange farrago be employed by Mr. Locket of Maiichoetor, for softening liis dice and mills, it deserves consideration. Should the nitre be used in too Seat quantity to be all carbonated by the gall, its oxygen may serve to consume some of the carbon of 9 steel, aod thus bring it nearer to iron. The recipe may be old, but it is a novelty to me. fm STEEL. STEEL. 731 abl« for softening the granular particles of iron during their combination with the carbon, by keeping it for a certain time at a red heat with powdered charoool, a casting is obtained, which, when submitted to the action of the hammer or rollers, furnislies a product known as "steel of cementation." During this operation the stratum of oxide which covers the particles of iron inside loses its oxygen, and passes again into a me- tallic state ; but the vacant spaces occasioned by this are filled up, as the ferruginous particles, which are in a semi-fluid state, reassumes the crystalline form. The carbonic acid (oxide f ) gas in escaping forms lar^e blisters on the surface of the metal, under which Uie softened mass crystallizes. On being broken, the interior of these blisters, instead of appearing of a dark color, indicating the presence of a stratum of protoxide, presents 8 brilliant and rainbow-tinted appearance, the yellowish and bluish tints distinguisJiing bronzed steel being observable. If this steel be wrought at a white heat> these blisters will weld in with the mass with the greatest facility. During cementation the carbon combines with the component particles of the iron in various proportions, depending in a great degree upon the chemical composition of those particles. It is therefore a vul- gar eiTor to suppose that steel of cementation contains more carbon at the surface than in the interior, as stated in all technological treatises. Thus, in the best Dannemora steel, it very frequently happens, when the cementation is finished, that the centre of the metal contains a much greater quantity of carbon than in the superficial portions It may also happen that steel produced from the best Dannemora bar iron will differ in an extraordinary manner as regards hardness in various portions of the bar; and for this reason, in steel works in England, the bars of steel are always broken into several pieces, in order to class those pieces together which are the most similar in quality. If ordinary iron be submitted to cementation, that is to say, iron in which the propor- tion of silica is ordinarily insignificant when compared with that of carbon, and if inde- pendently of this the iron is deficient in the quantity of phosphorus and arsenic necessary for easily softening the metallic molecules, only carburet oi iron and a little siliciuret of iron are produced, but the carbon does not combine with the silica. In this case the steel is aeficient in malleability and tenacity, for this reason, that the molecules will not unite or crystallize until they have taken up a quantity of carbon more than sufficient to produce steel. With regard to simple carburetted iron (when it contains more carbon), it either will not harden at all when tempered, or becomes friable and brittle when heated to redness, even when it does not contain more carbon than steel of good quality. The fracture of the steel of cementation, now under notice, is gray and dull, while steel of good quality is of a silvery aspect, and presents cubical crystals. The best steel can only be obtained by the cementation of forged iron ; whilst the Boetal is combining with the carbon, the iron must not enter into a complete state of fusion, as in that ease groups of crystals, each possessing a diff^erent degree of ^carbon- ization, would be formed; even the best Dannemora iron will not furnish a uniform froduct, fit for purposes of commerce, when melted with substances containing carbon, am well aware that the experiments of Clouet, Hachettc, and Breant, may be opposed to me, as set forth in various treatises on chemistry ; but these are unfortunately mere laboratory experiments, the authors of which have prudently concealed, or passed over in silence, all those which were unsuccessful. When the operator has obtained a regulus at the bottom of his crucible, and when, after immense trouble, he has succeeded in extracting a small portion of steel capable of being worked, he immediately hastens to publish his pretended discovery in some journal, of which others become faithful and credulous echoes : thus, since the manufacture of steel has become the subject of chemical inquiry, complaints are daily becoming more frequent upon the difficulty of obtaining steel capable of resisting the treatment to which it is subjected in the arts. If th^j persons who preside over the coining department either at London or Munich were consiilted, they would all agree in saying that it is now very difficult to meet with the quality of steel necessary for making the dies. Even in England good steel becomes more and more scarce. With regard to the manufactories of cemented or cast steel established upon the Continent, they furnish products the quality of which is so uncer- tain that the workman is often reduced, after having lost his time and trouble, to throw certain portions away, as they want the necessary uniformity and tenacity. All the artificial alloys of silver with steel, of which so much has been said, are not fit for anything, and are never met with in commerce. When the steel has been withdrawn from the cementing furnace, and after it has been broken and the pieces drawn out, they are submitted to one of the two following operations :-— The pieces, after being sorted, are piled one upon the other and welded together (this is called iPaggoting the steel) ; or the sorted pieces are placed in clay crucibles of a nearly cylindrical form, and cast in a reverberatory furnace, in which two crucibles are placed, one behind the other upon cakes of fire clay ; the orifice of these crucibles is closed by a flat cake of fire clay. The bars of cemented steel, as above mentioned, arc divided into pieces of one or two inches in length ; these pieces are distributed, according to their degree of carbonization, in vessels fixed to the walls ol the place in which the melting is carried on. . These diflferent qualities of steel are generally combined in such a manner as to obtain a product the best suited for the purposes to which cast steel is ordinarily applied. ^ In all treatises on practical chemistry it is asserted that, in order to melt steel, it is to be covered with a layer of glass or blast furnace slag; that the opening of the crucible is luted, or at least becomes firmly fixed during the operation; these assertions are however erroneous. In the first steel manufactories in Sheffield, steel only is put into the crucibles. With regard to the cover it is evident that it must adhere to the crucible, as it is necessary the operator should remove it from time to time with a bar of iron in order to ascertain the etate of the metal. ' In order to obtain steel of the first quality, it is not sufficient that the melted mass be run into moulds; the most essential point is to make the casting at the proper time, and for this purpose the operator must be guided by the quality of the steel. This is the duty of the workman, who from long practice can tell the suitable point of fusion, either by simple inspection, or by means of his bar of iron, with which he merely touches the sur^ce of the metal, being most careful not to plunge it into the melted mass. As the quality and uniformity of the steel depend in a great measure upon the experience and judgment of the workman who directs the casting, it follows that^ even in England, a good caster is much sought after and well paid. It is not difficult, therefore, to explain why so many of the attempts made to establish manufactories of cast steel in Germany have failed, and will again fail. Thanks to the errors propagated by technical works, and by the assertions of superficially informed travellers, who had frequently been purposely deceived, it was imagined that in order to obtain English steel of good quality, it was only necessary to melt cemented steel in a crucible, and afterward pour it into moulds when in a state of fusion. As soon as a crucible is emptied, it is replaced in the oven ; each crucible serves for one day's work, i.e. four or five castings, after which it is thrown aside. For ordinary purposes, the steel is run into cast-iron moulds of a prismatic form, previousljr heated and closed. When the steel is required for making saw-blades, plates, Ac, it is run into large moulds of a parallelopiped form. Steel which is very hard and highly car- bonized, contracts considerably in the moulds ; great skill is therefore required to run it into the moulds in such a manner that no vacuum may be produced. In that part of the prism corresponding to the jet, a funnel-shaped aperture from 1 to 2 inches deep is formed ; this is detached and melted down with other pieces of steel. ' The transverse fracture of a prism of hard steel is silvery, and has a number of rays radiating from the centre ; steel less hard is, on the contrary, of a uniform granular and crystalline texture. This steel possesses all the brittleness of cast metal. By fusion, steel of cementation acquires peculiar properties, and does not sweat so much as before casting. When steel is produced from iron of bad quality, and carburets of a different nature are produced during cementation, the melting, instead of improving it, renders it much •worse ; as, in that case, the different carburets of iron, which are of inferior quality, separate still more during cooling. This has given rise to an old saying, well known among English founders, that "when the devil is put into the crucible, nothing but the devil will come out" It is to the existence of these heterogeneous metallic carburets, which are produced during cementation in iron of inferior quality, and which forms new combinations during the fusion of the metal, that the complaints of workmen working in steel are to be attributed. In fact, these carburets being only, so to speak, agglutinated, even in bars of forged steel, each of them at the moment of tempering is contracted or dilated more or less than the one immediately adjoining it, so that from that time a separation cona- mences between the unequally carbonized layers ; in other words a flaw or crack is produced, which may be distinguished by a peculiar noise at the moment when the steel is plunged in the water, or at least there is a tendency to separation, which only requires the cooperation of an exterior cause, such as a shock, to effect This is often observed in razors, &c. The transverse fracture of cast steel ought to present a perfectly homogeneous surface when the bar is broken by a sharp blow, after being cut or marked with a chisel. The slight inequalities which are perceptible ought to be undulating, and to blend insensibly at their bases with the rest of the metallic surface. When, on the contrary, they stand out perpendicularly, the conclusion may be arrived at, that this portion of the bar was the point of contact of two unequally-carbonized layers, which, by separating either at the moment of tempering or at a later period, had inevitably given rise to this rupture. Indian steel, or wootz. — ^The wootz ore consists of the magnetic oxide of iron, united with quartz, in proportions which do not seem to differ much, being generally about 42 732 STEEL. STEEL. 733 4 ■ill of quartz, and 58 of magnetic oxyde. Its grains are of various size, down to a sandy tex^ ture. The natives prepare it for smeltins: by pounding the ore, and winnowin* away the stony matrix, a task at which the Hindoo females are very dexterous. The manner in which iron ore is smelted and converted into wootz or Indian steel, by the natives at the present day, is probably the very same that was practised by them at the time of the invasion of Alexander; and it is a uniform process, from the Himalaya mountains to Cap€ Comorin. The furnace or bloomery in which the ore is smelted, is from four to five feel high; It is somewhat pear-shaped, being about two feet wide at bottom, and one foot af top; It IS built entirely of clay, so that a couple of men can finish its erection in a few hours, and have it ready for use the next day. There is an opening in front about a foot or more m height, which is built up with clay at the commencement, and broken down at the end, of each smelting operation. The bellows are usually made of a goat's skin, which has been stripped from the animal without ripping open the part covering the belly. The apertures at the legs are tied up, and a nozzle of bamboo is fastened in the opening formed by the neck. The orifice of the tail is enlarged and distended by two slips of bamboo. These are grasped in the hand, and kept close together in making the stroke for the blast; in the returning stroke they are separated to admit the air. By working a bellows of this kind with each hand, making alternate strokes, a pretty uniform blast IS produced. The bamboo nozzles of the bellows are inserted into tubes of clay, which pass into the furnace at the bottom corners of the temporary wall in front. The furnace IS filled with charcoal, and a lighted coal heinjj introduced before the nozzles, the mass in the interior is soon kindled. As soon as this is accomplished, a small portion of the ore, previously moistened with water, to prevent it from running through the charcoal, but without any flux whatever, is laid on the top of the coals, and covered with charcoal to fill up the furnace. In this manner ore and fuel are supplied; and the bellows are urged for 3 or 4 hours, when the process is stopped; and the temporary waU in front being broken down, the bloom IS removed by a pair of tongs from the bottom of the furnace. It is then beaten with a wooden mallet, to separate as much of the scoriae as possible from it, and, while Btill red-hot, it is cut through the middle, but not separated, in order merely to show Ihe quality of the interior of the mass. In this state it is sold to the blacksmiths, who make it mto bar iron. The proportion of such iron made by the natives from 100 parts of ore, is about 15 parts. In converting the iron into steel, the natives cut it into pieces, to enable it to pack better in the crucible, which is formed of refractory clay, mixed with a large quantity of charred husk of rice. It is seldom charged with more than a pound of iron, which is put in with a proper weight of dried wood chopped small, and both are covered with one or two green leaves ; the proportions being in general 10 parts of iron to 1 of wood and leaves. The mouth of the crucible is then stopped with a handful of tempered clay, rammed in very closely, to exclude the air. Th« wood preferred is the Cassia anriculata, and the leaf that of the ^sckpias zieanteay or the Convolmilus laurifolius. As soon as the clay plugs of the crucibles are Ur>', from 20 to J4 of them are built up in the form of an arch, in a small blast furnace; they are icept covered with charcoal, and subjected to heat urged by a blast for about two hours and a half, when the process is considered to be complete. The crucibles beino- now taken out of the furnace and allowed to cool, are broken, and the steel is foSnd in theform of a cake, rounded by the bottom of the crucible. When the fusion has been perfect, the top of the cake is covered wirh striae, radiating from the centre, and is free from holes and rough projections ; but if the fusion has been imperfect, the surface of the cake has a honeycomb appearance, with projecting lumps of malleable iron. On un average, four out of five cakes are more or less defective. These imperfections have been tried to be corrected in London by re-melting the cakes, and running them into ingots ; but it is obvious, that when the cakes consist partially of malleable iron and of unreduced oxyde, simple fusion cannot convert them into good steel. When care is taken however, to select ouly such cakes as are perfect, to re-melt them thoroughly, and tilt them carefully into rods, an article has been produced which possesses all the re- quisites of fine steel m an eminent degree. In the Supplement to the Encyclopaedia Britannica, article Cutlery, the late Mr. Stodart, of the Strand, a very competent jud-e, has declared « that for the purposes of fine cutlery, it is infinitely superior to the best English cast steel." The natives prepare the cakes for being drawn into bars by annealing them for several Hours m a small charcoal furnace, actuated by bellows ; the current of air beino- made to play upon the cakes while turned over before it ; whereby a portion of the combined carbon is probably dissipated, and the steel is softened ; without which operation the cakes would break in the attempt to draw them. They are drawn by a hammer of a lew pounds weight. The natives weld two pieces of cast steel, by giving to each a sloping face jagged all ever with a small chisel ; then applying them with some calcined borax between, and tying them together with a wire, they are brought to a full red heat, and united by a few smart blows of a hammer. The ordinary bar iron of Sweden and England, when converted by cementation into Bteel, exhibits upon its surface numerous small warty points, but few or no distinct vesicular eruptions ; whereas the Dannemora and the Ulverston steels present, all over the surface of the bare, well raised blisters, upwards of three-eighths of an inch in di- ameter horizontally, but somewhat flattened at top. Iron of an inferior description, when highly converted in the cementing-chest, becomes gray on the outer edges of the fracture; while that of Dannemora acquires a silvery color and lustre on the edges, with crystalline facets within. The highly converted steel is used for tools that re- quire to be made very hard ; the slightly converted, for softer and more elastic articles> such as springs and sword blades. One of the greatest improvements which this valuable modification of iron has ever received is due to the late Mr. Josiah M. Heath, who, after many elaborate and costly researches, upon both the small and the great scale, discovered that by the introduction of 1362 1863 1864 annall portion, 1 per cent, and even less, of carburet of manganese into the melting-pot along with the usual broken bars of blistered steel, a cast steel was obtained, after f usioD,of 734 STEEL. STEREOTYPE PRINTING. 735 I iiSI ! a quality very superior to "wrhat the bar steel would have yielded without the manganese, and moreover possessed of the new and peculiar property of being weldable either to itself or to wrought iron. He also found that a common bar-steel, made from an in- ferior mark or quality of Swedish or Russian iron, would, when so treated, produce an excellent cast steel. One immediate consequence of this discovery has been the re- , duction of the price of good steel in the Sheffield market by from 30 to 40 per cent., and likewise the manufacture of table-knives of cast steel with iron tangs welded to them ; whereas, till Mr. Heath's invention, table-knives were necessarily made of sheer- steel, with unseemly wavy lines in them, because cast steel could not be welded to the tangs. Mr. Heath obtained a patent for this and other kindred meritorious in- ventions on the 5th of April, 1889; but, strange and melancholy to say, he never de- rived any thing from his acknowledged improvement but vexation and loss, in con- sequence of a numerous body of Sheffield steel manufacturers having banded together to pirate his patent., and to baffle him in our complex law courts. I hppe, however, that eventually justice will have its own, and the ridiculously unfounded pretences of the pirates to the prior use of carburet of manganese will be set finally at rest. It is supposed that fifty persons at least embarked in this pilfering conspiracy. By a re- cent decision of the Judicial Committee of the Privy Council, the heirs of Mr. Heath have obtained a prolongation of the term of the patent for seven years from this date, February, 1853. The furnace of cementation in which bar-iron is converted into bar or blistered steel is represented in Jigs. 1362,68,64. It is rectangular and covered in by a groined or cloister arch : it contains two cementing chests, or sarcophaguses, c, c, made either of fire-stone of fire-bricks : each is 2^ feet wide, 3 feet deep, and 12 long; the one being placed on the one side, and the other on the other of the grate, a, b, which occupies the whole length of the furnace, and is from 13 to 14 feet long. The grate is 14 inches broad, and rests from 10 to 12 inches below the inferior plane or bottom level of the chests; the height of the top of the arch above the chests is 5| feet ; the bottom of the chests is nearly on a level with the ground, so that the bars do not need to be lifted high in charging the furnace. The flame rises between the two chests, passes also below and round them through the horizontal and vertical flues, d, and issues from the furnace by an opening, h, in the top of the vault, and by orifices, t, which communicate with the chimneys placed in the angles. The whole is placed within a large cone of bricks, 25 or 30 feet high, and open at top : this cone increases the draught, makes it more regular, and carries off the smoke away from the establishment. The furnace has three doors; two, t (fg. 1363), above the chests, serve to admit and to remove the bars ; they are about 7 or 8 inches square : in each of them a piece of sheet-iron is put, folded back on its edges; upon which the bars are made to slide, so as to save the wall. A workman enters by the middle door, p, to arrange the bars ; the trial bars are taken out from time to time by the apertures, s, (fg. 1362.) left in the sides of the chests. The bars are laid in strata, along with wood charcoal in powder, in the said chests; they are about three inches broad, and one-third of an inch thick ; they must not be placed too near each other, lest they should get welded together; the air or uppermost layer is covered with a stratum of loamy matter from 4 to 6 inches thick. The furnace must be gradually heated, not reaching its maximum temperature before 8 or 9 days, and the cooling lasts 5 or 6 days; the whole operation 18 or 20 days, and sometimes more, according to the quality of the steel to be cemented. About 13 tons of coals are consumed in this period. It is of consequence that the refrigeration be slow, to favor the crystallization of the metal. The grain of the steel varies with the rate of cooling, the largest and whitest grain denoting the most fusible steel. Heavy Steel. E. Thomas, JcTcnield works, Birminqham, manufacturer. The articles exhibited illustrated the heavy steel " toy" trade of Birmingham. Brazil axes ; Ame- rican wedge axes, and hand hatchet ; shingling hatchets, assorted patterns ; coopers* adze and axe; round and square eye adze; mahogany squaring axe; English car- penter's axe; eyed shell and screw auger; double plane iron; socket chisel; trowel; gun and hand harpoons; improved grass shears; and a variety of garden tools, to screw into one handle. The manufacture of the axe used by the backwoods-men, of the hoe used in the agriculture of the tropics, the pick used by the Caffirs of the Cape, and the harpoon of the whale-fisher, give employment to many artizans of its vicinity. In order to convey a general idea of the process by which these articles are "got up," the manufacture of an ordinary axe may be selected. A piece of iron is taken, and after being heated is doubled over a piece of steel, corresponding in form to the future eye which is to hold the shank; is not then welded together. A small piece of steel which is intended to form the future cutting edge, is heated along with the iron back to a welding heat, and is passed under a tilt hammer (that is, a large hammer driven by steam or water), which speedily flattens it out ; it is then exposed to another heat, and the eye is completed with the small hammer. The superfluous iron or steel is removed by a pair of lai^e scissors. The the process of hardening and tempering follow ; the grinding is performed on stones which out away the iron and disclose the steel edge. The "glazing" on emery "bobs" or wheels succeeds, and the polishing is effected by means of emery and oil on a similar tool. Considerable improvement in appearance is imparted by the use of a blue var nish which is applied to the axe, and drying in a small stove. "Toy" is a technical term applied to an anvil, a hammer, and various other objects which are comprised under the term " heavy steel" In the year 1843, 25,000 tons of steel were annually converted in this country, and of that quantity not more than 2,500 were made from the best Swedish iron. For the remainder, inferior qualities of iron, such as the Russian iron marked CCND, from the foiges of Count Demidoff, were used ; that iron was made with charcoal, and could be caUed inferior only when compared with that made from the Dannemora ore. STEEL PLATE ENGRAVING. An entire change in engraving has taken place by the substitution of steel for copper plates. An engraving made upon copper is speedily rendered useless by the process of jnking, and the friction necessary to remove the sn- perfluous ink. The rubbing with whitening to clean the face of the plate wears away the surface and renders it valueless after a few thousand impressions. The Queen's head on the postage stamp has been only once engraved. It had, in 1842, been multiplied 6,000 times — that is to say, the original produced 6,000 plates, which printed all the postage stamps of the above kind which had been used since the introduction of Rowland Hill's measure up to the period stated. The multiplication of a steel plate is a feature of some importance : a plate is en- graved and hardened ; from this an impression is taken upon a softened steel roller ; Siis steel roller is then hardened, and softened steel plates being passed under it, an impression is imparted to them ; they are then hardened, and are equal to the origioaj as to their impressions. This method is adopted in bank-note engraving ; and the postage stamp plates are produced by the same meana STEREOTYPE PRINTING signifies printing by fixed types, or by a cast typo- graphic plate. This plate is made as follows : — The form, composed in ordinary types, and containing one, two, three, or more pages, inversely as the size of the book, being laid flat upon a slab, with the letters looking upwards, the faces of the types are brushed over with oil, or preferably, with plumbago (black lead.) A heavy brass rectangulal fratne of three sides, with bevelled borders, adapted exactly to the size of the pages, it then laid down upon the chase,* to circumscribe three sides of its typography ; but Iha fourth side, which is one end of the rectangle, is formed by placing near the types, and over the hollows of the chase, a single brass bar, having the same inwards sloping bevel as the other three sides. The complete frame resembles that of a picture, and serves to define the area and thickness of the cast, which is made. by pouring the pap of Paris plaster into its interior space, up to a given line on its edges. The plaster mould, which soon sets, or becomes concrete, is lifted gently oflf the types, and inmiediately placed upright on its edge in one of the cells of a sheet-iron rack, mounted within the cast-iron oven. An able workman will mould ten sheets octavo in a day, or 160 pages. The moulds are here exposed to air heated to fully 400° F., and become perfectly dry in the course of two hours. As they are now friable and porous, they require to be delicately handled. Each mould, containing generally two pages octavo, is laid, with the im- pression downwards, upon a flat cast-iron plate, called the floating-plate ; this plate being itself laid on the bottom of the dipping-pan, which is a cast-iron square tray. With its upright edges sloping outwards. A cast-iron lid is applied to the dipping-pan, and secured in its place by a screw. The pan having been heated to 400° in a cell of the oven, under the mould-rack, previous to receiving the hot mould, is ready to be plunged into the bath of melted alloy contained in an iron pot placed over a furnace, .Jind it is dipped with a slight deviation from the horizontal plane, in order to facilitate the escape of the air. As there is a minute space between the back or top surface of the mould and the lid of the dipping-pan, the liquid metal, on entering into the pan through the orifices in its corners, floats up the plaster along with the iron plate on which it had been laid, thence called the floating-plate, whereby it flows freely into every line of the mould, through notches cut in its edge, and forms a layer or lamina upon ite face, of a thickness corresponding to the depth of the border. Only a thin metal film is left upon the back of the mould. The dipping-pan is suspended, plunged, and removed by means of a powerful crane, susceptible of vertical and horizontal motions in all direc- tions. "When lifted out of the bath, it is set in a water-cistern, upon bearers so placed as to allow its bottom only to touch the surface. Thus the metal first concretes below, * Chase {ckoBait, frame, Fr.), quoin Uoin, wedge, Kr.) are terms which show that the art of printixig came directly from France to Eiigland. 736 STEVENSON'S REVOLVING LIGHTHOUSE. STEVENSON'S REVOLVING LIGHTHOUSE. 737 ''isn I fil! while by remaining fluid above, it continues to impart hydrostatic pressure during the shrinkage attendant upon refrigeration. As it thus progressively contracts in volume, more melted metal is fed into the corners of the pan by a ladle, in order to keep up the hydrostatic pressure upon the mould, and to secure a perfect impression, as well as a solid cast Were the pan more slowly and equably cooled, by being left in the air, the thin film of metal upon the back of the inverted plaster cake would be apt to solidify firsts and intercept the hydrostatic action indispensable to the purpose of filling all the lines in its face. A skilful workman makes five dips, containing two pages octavo each in the course of an hour, or about nine and a half octavo sheets per day. The pan being taken asunder, the compound cake of mould and metal is removed, and beat upon ite edges with a wooden mallet, to detach the superfluous metaL The stereotype plate is then handed over to the picker, who planes its edges truly square, turns its back flat upon a lathe to a determinate thickness, and carefully removes the little imperfections occasioned by dirt or air left among the letters when the mould was cast Should any of them be damaged in the course of the operation, they must be cut out> and replaced by soldering in separate types of the same size and form. STEVENSON'S REVOLVING LIGHTHOUSE. This apparatus consists of two parts. The principal part is a right octagonal hollow prism composed of eight large lenses, which throw out a powerful beam of light whenever the axis of a single lens comes in the line between the observer and the focus. This occurs once in a minute, as the frame which bears the lense revolves in eight minutes on the rollers place be- neath. The subsidiary parts consist of eight pyramidal lenses inclined at an angle of 80° to the horizon, and forming together a hollow truncated cone, which rests above the flame like a cap. Above these smaller lenses (which can only be seen by looking from below) are placed eight plain mirrors, whose surfaces being inclined to the horizon at 60° in the direction opposite to that of the pyramidal lenses, finally causes all the Mght made parallel by the refraction of these lenses to leave the mirror in a horizontal direction. The only object of this part is to turn to useful account, by prolonging the duration of the flash, that part of the light which would otherwise escape into the at- mosphere above the main lenses. This is effected by giving to the upper lenses a slight horizontal divergence from the vertical plane of the principal lenses. Below are five tiers of totally reflecting prisms, which intercept the light that passes below the great lenses, and by means of two reflections and an intermediate refraction project them in the shape of a flat ring to the horizon. Fixed dioptric apparatus of the first order (same as that at the Isle of May, with va- rious improvements). The principal part consists of a cylindric belt of glass which surrounds the flame in the centre, and by its action refracts the light in a vertical di- rection upward and downward, so as to be parallel with the focal plane of the system. In this way it throws out a«at ring of light equally intense in every direction. To near observers, this action presents a narrow vertical band of light depending for its breadth on the extent of the horizontal angle embraced by the eye. This arrangement therefore fulfils all the conditions of a fixed lights and surpasses in effect any arrangement of par- abolic reflectors. In order to save the light which would be lost in passin*^ above and below the cylindrical belt, curved mirrors with their common focus in the lamp were formerly used; but by the present engineer, the adaptation oi catadioptric zouqs, to this part of the apparatus was, after much labor, successfully carried out These zones are triangular, and act by a total reflexion, the inner face refracting, the second totally re- flecting, and the third or outer face, a second time refracting, so as to cause the light to emerge horizontally. The apparatus has received many smaller changes by the intro- duction of a new mode of grouping the various parts of the frame work, by which the passage of the light is less obscured in every azimuth. During the last four years these improvements have been introduced into the lighthouses of Scotland. Mechanical lamps of four wicks, in which the oil is kept continually overflowing by means of pumps which raise it from the cistern below ; the rapid carbonization of the wicks, which would be caused by the great heat is thus avoided. The flames of the lamp reach their best effect in three hours after lighting, i. e. after the whole of the oil in tho cistern, by passing and repassing over the wicks repeatedly, has reached its maximum temperature. After this the lamp often burns 14 hours without sensible diminution of the light, and then rapidly falls. The height varies from 16 to 20 times that of the Argand flame of an inch in diameter; and the quantity of oil consumed by it is greater nearly in the same proportion. ./ o j Revolving light with axial rotation, by which one half the number of reflectors and one half the quantity of oil are designed to be saved. Intended for illuminating any arch of not more than 180°. The intervals of time of illumination are equal within the whole of the illuminated arch, instead of unequal as in the reciprocating light The reflectors are also of a new form consisting of parabolic strips of different focal diatancea; Ordinary parabolic reflector rendered holophotal (where the entire light is parallel- ieed) by a portion of a catadioptric annular lens. The back part of the parabolic conoid is cut off, and a portion of a spherical mirror substituted, so as to send the rays again through the flame. All the light intercepted by the annular lens is lost in the ordinary reflector. Holophotal catadioptric annular lens apparatus (unfinished). This is a combination ot a hemispherical mirror, and a lens with totally rellecting zones ; the peculiarity of this arrangement is, that the catadioptric zones, instead of transmitting the light in parallel horizontal j)late8, as in Fresnel's apparatus, produces, as it were, an extension of the lenticular or quaquaversal action of the central lens by assembling the light around its axis in the form of concentric hollow cylinders. (The above instruments belong to the Board of Northern Lights.) The early method of illuminating lighthouses was by coal or wood fires contained in " chauffers." The Isle of Man light was of this kind until 1816. The first decided im- provement was made by Argand, in 1784, who invented a lamp with a circular wick, the flame being supplied by an external and internal current of air. To make these lamps more effective for lighthouse illumination, and prevent the ray of light escaping on all sides, a reflector was afterward added ; this threw the light forward in parallel rays toward such points of the horizon as would be useful to the mariner. Good reflectors increase the luminous effect of a lamp about 400 times; this is the "catoptric" system of lighting. When reflectors are used, there is a certain quantity of light lost^ and the ** dioptric" or refracting system, invented by the late M. Augustm Fresnel, is designed to obviate. this effect to some extent: the "catadioptric" system is a still further im- provement and acts both by refraction and reflexion. Lights of the first order have aa interior radius or focal distance of 36*22 inches, and are lighted by a lamp of four con- centric wicks, consuming 570 gallons of oil per annum. The appearance of light called short eclipses has hitherto been obtained by the fol- lowing arrangement: — An apparatus for a fixed light being provided, composed of a central cylinder and two zones of catadioptric rings forming a cupola and lower part^ a certain number of lenses are arranged at equal distances from each other, placed upon an exterior move- able frame making its revolution around the apparatus in a given period. These lenses, composed of vertical prisms, are of the same altitude as the cylinder, and the radius of their curves is in opposite directions to those of the cylinder, in such a manner that at their passage they converge into a parallel pencil of light, all the divergent rays emit- ted horizontally from the cylinder producing a brilliant effect^ like that obtained by the use of annular lenses at the revolving lighthouses. The first improvement exhibited has special reference to the light, and produces a considerable increase in its power, while the simplicity of the optical arrangements is also regarded. It consists, firstly, in completely dispensing with the moveable central cylindrical lenses ; secondly, it replaces these by a single revolving cylinder composed of four annular lenses and four lenses of a fixed light introduced between them; but the number of each varying according to the succession of flashes to be produced in the period of revolution. The second improvement, of which already some applications that have been made serve to show the importance, consists in a new method of arranging the revolving parts, experience having shown that the arrangements at present in use are not very faulty A short time is suflBcient for the action of the friction rollers, revolving on two parallel planes, to produce by a succession of cuttings a sufficiently deep groove to destroy the regularity of the rotatory movement To obviate this great inconvenience the friction rollers are so placed and fitted, on an iron axis with regulating screws and traversing between two bevelled surfaces, that when an indentation is made in one place they can be adjusted to another part of the plates which is not so worn. The third improvement produces the result of an increase of the power of the flashes in revolving lighthouse apparatus to double what has been obtained hitherto. By means of lenses of vertical prisms placed in the prolongation of the central annular lenses, the divergent rays emerging from the catadioptric zone are brought into a straight line, and a coincidence of the three lenses is obtained. The whole of the prisms, lenses, and zones, are mounted with strength and simplicily, accurately ground and polished to the correct curves according to their respective positions, so as to properly develope this beautiful system of Fresnel. The glass of which they are composed is of the clearest crystal color, and free from that green hue which so materially reduces the power of the lights and is considered objectionable for apparatus of this kind. The lamp by which tlie apparatus is to be lighted consists of a concentric burner with four circular wicks attached to a lamp of simple construe tion, the oil being forced up to the burner by atmospheric pressure only, so that ther« are no delicate pumps or machinery to become deranged. 738 STILL. iui; i i Improved lantern and revolvmg apparatus for a light vessel. The principal improTe- ment consists in constructing the nnachinery to work beneath the dect, instead of In tha lantern as formerly. A vertical rod working in metal beariues is attached to the masL with a large gnn-metal pinion fixed to the top of the rod/Ttrfadphrto whichT^. necessary to hoist the lantern, wherein a train of cog-wheels is pL^to co^ect w t" the pinion and communicate the motion obtained therefrom to trtraversinA^^^^^^ tha supporte the lamps and reflectors. The advantages of this arrZeSTe ?h^ the lanterns can be made much lighter, the rolling of thTvessel caused SX^reatrweght at the mast head is greatly diminished, and the machinery being more under oTS and better protected works with greater regularity and precision. An idea of the utility of these improvements may be gained by reflecting thnf th* TtlTmv r %"'" V' light-vessels a're placed are at^all tLes diS^ult oft^^^^^^^^ stormy weather, when accidents are most likely to occur, quite unapproachable ; so that t^Ie apprSt'd. "'' ''''"'"° ^'''' '^'"^^^ ^'^ "^^^"^^ '^ de^Lgement is greatly aimh^rJn.t"'' t" ^^r^'^S^ <^«"^«^ fr«™ the novel construction of the lamps and gimbal work, which, by a movement exactly coinciding with the motion of the vessel causes a perfect level to be always maintained, and enfures the pTopTflow of oS the burners, however irregular that motion ma^ be. This improvement is not of so re- cent an introduction as the former, but when It was first invented by one of the ex- .wiriL K^'^^^-n a"" '^°]P^^^ revolution in the apparatus for floating lights, and en- ^ut^^ ^.K^'^"^ ^"^r.^ '^'VP^ ^'^^ parabolic reflectors, to be used inst^d of the old lamps with smoky flat wicks. hv^h?^^ (-^^^^ftic. Fr. -Blase, Germ.), is a chemical apparatus, for vaporizing liquid, by heat in one part called the cucurbit, and condensing the vapors into liquids in anotheJ jmrt, called the refrigeratory ; the general purpose of both combined being to separate the more volatile fluid particles from the less volatile. In its simpleslTrm, it consTsi; InHnlTh'"/ ^ 'T'T' "^ "^ ^ r^'-'^^/P^d matrass and a capital, furnis'hed whh a Jianting tube for conducting away the condensed vapors in drops: wheice the term stiU from the Latin verb stillare to drop. Its chief employment in this count.^ being to elim! mate alcohol, of greater or less strength, from fermented wash, I shall devote this article to a description of the stills best adapted to the manufacture of British spirits riferrini to chemical authors* for those fitted for peculiar objects reierring In respect of rapjdity and extent of work, stills had Attained to an extraordinary pitcli of perfection in Scotland about thirty years ago, when legislative wisdom thoueht fit to levy the spirits duty, per annum, from each distiller, according to the capacity of hii still. It having been shown, m a report presented to the House of Commons in 1799 that an SO-gallon still could be worked ofl-in eight minutes, this fact was made the basis' of a new fiscal law on the supposition that the maximum of velocity had been reached But, instigated by the hopes of enormous gains at the expense of the revenue, the distill- ers soon contrived to do the same thing in three minutes, by means of broad-bottomed shal ow stills, with stirring-chains, and lofty capitals. In the year 1815, that preposter- ous law, which encouraged fraud and deteriorated the manufacture, was repealed The whiskey duties having been since levied, independently of the capacity of the still, upon the quantity produced, such rapid operations have been abandoned, and processes of econ- omy in fuel, and purity m product, have been sought after. One of the greatest improvements in modern distilleries, is completing the analysis rS?" l/^r ?' '•''^ operation. Chemists had been long familiar with the contrivance of Woulfe, for impregnating with gaseous matter, water contained in a range of bottles • but they had not thought of applying that plan to distillation, when Edouard Adam' an illiterate workman of Montpellier, after hearing accidentally a chemical lecture upon that apparatus, bethought himself of converting it into a still He caused the boiling-hot vapors to chase the spirits successively out of one bottle' into another so as to obtain m the successive vessels alcohol of any desired strength and purity, « oJ am and the same heat "He obtained a patent for this invention in 1801, and was soon afterwards enabled, by his success on the small scale, to set up in his native city a mag- mficent distillery which excited the admiration of all the practical chemists of thft day In November, 1805, he obtained a certificate of certain improvements for ex- tractmg from wine, at one process, the whole of its alcohol. Adam was so ovenoyed. after making his first experiments, that he ran about the streets of Montpellier, telling everybody of the surprising results of his invention. Several competitors soon entered the lists with him, especially Solimani, professor of chemistry in that city, and Isaae ♦ The treatises of LeNormand and Dubruiifaut may also be consulted. The French stills are in nn»tml SiTof ^S ' *"** ""^ """^^ ^'^" ""^ P^"""^"' " »° ^ «nfit for filing Se glSSSS STILL. 739 Berard, distiller in the department of Gard ; who, having contrived ether forms of cos tinuous stills, divided the profits with the first inventor. The principles of spirituous distillation may be stated as follows :— The boiling point oC' alcohol varies with its density or strength, in conformity with the numbers in the fol- lowing table: — Speafic grtLYity. Boiling^ point, by Fahrenheit's scale. Specific gfravity. Boiling point, bj Fahr«nheit% male. 0-7939 168-5® 0-8875 181-0" 0-8034 168-0 0-8631 1830 0-8118 168-5 0-8765 187-0 0-8194 1690 0-8892 190-0 0-8265 172-5 0-9013 194-0 0-8332 173-5 0-9126 197-0 0-8397 175-0 0-9234 199-0 0-8458 177-0 0-9335 201-0 0-8518 179-0 See also the table under Alcohol, page 22. Hence, the lower the temperature of the spirituous vapor whsch enters the refti- geratory apparatus, the stronger and purer will the condensed spirit be ; because the oflensive oils, which are present in the wash or wine, are less volatile than alcohol, and are brought over chiefly with the aqueous vapor. A perfect still should, therefore, consist of three distinct members ; first, the cucurbit, or kettle ; second, the rectifier, for inter- cepting more or less of the watery and oily particles ; and third, the refrigerator, or conden- ser of the alcoholic vapors. These principles are illustrated in the construction of the still represented in^g». 1365, 1366, 1367, 1368, 1369 ; in which the resources of the most refined French stills are combined with a simplicity and solidity suited to the grain distilleries of the United Kingdom. Three principal objects are obtained by the arrangement here shown; first, the extraction from fermented wort or wine, at one operation, of a spirit of any desired cleanness and strength ; second, great economy of time, labor, and fuel ; third, freedom from all danger of blowing up or boiling over, by mismanaged firing. When a com- bination of water, alcohol, and essential oil, in the state of vapor, is passed upwards through a series of winding passages, maintained at a determinate degree of heat, between 170° and 180°, the alcohol alone, in any notable proportion, will retain the elastic form, and will proceed onwards into the refrigeratory tube, in which the said passages terminate ; while the water and the oil will be in a great measure condensed, arrested, and thrown back into the body of the still, to be discharged with the efiete residuum. The system of passages or channels, represented in^g. 1366, is so contrived as to bring the mingled vapors which rise from the alembic a, into ample and intimate contact with metallic surfaces, maintained, in a water-bath, at a temperature self-regulated by a heat- governor. See Thermostat. The neck of the alembic tapers upwards, as shown at 6, fig. 1365 ; and at c,fig, 1366, it enters the bottom, or ingress vestibule, of the rectifier c,/. /is its top or egress vestibule, which communicates with the bottom one by parallel cases or rectangular channels d, <£, d, of which the width is small, compared with the length and height. These cases are open at top and bottom, where they are soldered or rivet«l into a genenu frame within the cavity, enclosed by the two covers /, c, which are secured round their edges e, e, e, e, with bolts and packing. Each case is occupied with a numerous series of shelves or trays, placed at small distances over each other, in a horizontal or slightly inclined position, of which a side view is given in fig. 1367, and cross sections at d, d, J^ fig. 1366. Each shelf is turned up a little at the two edges, and at one end, but slop^d down at the other end, that the liquor admitted at the top may be made to flow slowly backwards and forwards in its descent through the system of shelves or trays, as in- dicated by the darts and spouts in fig. 1367. The shelves of each case are framed together by two or more vertical metallic rods, which pass down through them, and are fixed to each shelf by solder, or by screw-nuts. By this means, if the cover/, be removed, the sets of shelves may be readily lifted out of the cases and cleaned ; for which reason they are called moveabU. The intervals i, i, i,fig. 1366, between the cases, are left for the free circulation of the water contained in the bath-vessel g, g ; these intervals being considerably narrower tha* the cases. • Fig. 1368 represents in plan the surface of the rectifying cistern, shown in two different sections in^ig*. 1366 and 1367. h,k,fig$, 1366 and 1368, is the heat-governor. 740 STILL. STILL. 741 P' lii. I iii i it i shaped somewhat like a pair of tongs. Each leg is a compound bar, consisting of • flat bar or ruler of steel and one of bmss alloy, riveted facewise together having I?e5 -h?.rP '"? ^T- ^^" ^^"^'' ^' ^> "^ J«'"^d '^ '^' fr«« ends of tSese coCun^^ bar^ Which, receding by increase and approaching by decrease of temperature, act by a ?ey« 2 the stopcock /, fixed to the pipe of a cold-water back, and are so adjusted by a screw-nut. that whenever the water in the bath vessel g, g, rises above the desired temperature! cold water will be admitted, through the stopcock /, and pipe n, into the bottom of the cistern, and will displace the over-heated water by the overflow-pipe m. Thus a perfect equihbnum of caloric may be maintained, and alcoholic vapor of correspondent uniformity transmitted to the refrigeratory. ' if'ig. 1369 is the cold condenser, of similar construction to the rectifier, /ig. 1366; only the water cells should be here larger in proportion to the vapor channels d, d. This refrigeratory system will be found very powerful, and it presents the great advantage of perniitting its intenor to be readily inspected and cleansed. It is best made of laminated tin, hardened with a little copper alloy. The mode of working the preceding apparatus will be understood by the following instructions. Into the alembic, a, let as much fermented liquor be admitted as will pr(^ tect Its bottom from being injured by the fire, reserving the main body in the charging- back. Whenever the ebullition in the alembic has raised the temperature of the water- Wr/' ^\^ the desired pitch, whether that be 170°, 175o, or 180°, the thermostatic instrument is to be adjusted by its screw-nut, and then the communication with the chargmg-back is to be opened by moving the index of the stopcock o, over a proper portion of its quadrantal arch. The wash will now descend in a slender equable stream, through the pipe o, /, thence spread into the horizontal tube p, p, and issue trom the orifices of distribution, as seen in the figure, into the respective flat trays or spouts. 1 he manner of its progress is seen for one set of trays, in fig. 1059. The direc tion of the stream in each shelf is evidently the reverse of that in the shelf above and wi hbiV ^"^»^-"P end of one shelf corresponding to the discharge slope of iU By diffusmg the cool wash or wine in a thin film over such an ample range of sur- faces, the constant tendency of the bath to exceed the proper limit of temperature is counteracted to the utmost, without waste of time or fuel; for the wash itself, in transitu, becomes boilmg-hot, and experiences a powerful steam distillation. By this arrangement a very moderate influx of cold water, through the thermostatic stopcock, suffices to temper the bathj such an extensive vaporization of the wash producing a far more powerful refrigerant influence than its simple heating to ebullition. It deserves to be remarked; that the maximum distillatory effect, or the bringing over the greatest quantity of pure spintsm the least time, and with the least labor and fuel, is here accomplished without the least steam pressure in the alembic ; for the passages are ill pervious to the vapor; whereas, in almost every wash-still heretofore contrived fbr similar purposes, the spirituous vapors must force their way through successive layert of liquid, the total pressure produced by which causes undue elevation of temperature, and obstruction to the process. Whatever supplementary refrigeration of the vapors in their passage through the bath may be deemed proper, wUl be administered by the ther- mostatic regulator. Towards the end of the process, after all the wasli has entered the alembic, it may be sometimes desirable, for the sake of despatch, to modify the thermostat, by its adjusting- screw, so that the bath may take a higher temperature, and allow the residuary feints to run rapidly over, into a separate cistern. This weak fluid may be pumped back into the alembic, as the preliminary charge of a fresh operation. The above plan of a water-bath regulated by the thermostat, may be used simply as a rectifying cistern, without transmitting the spirit or wash down through it. The series of shelves will cause the vapors from the still to impinge against a most ex- tensive system of metallic surfaces, maintained at a steady temperature, whereby their watery and crude constituents will be condensed and thrown back, while their fine alcoholic particles will proceed forwards to the refrigeratory. Any ordinary still may be readily converted into this self-rectifying form, by merely interposing the cistern, fig. 1366, between the alembic and the worm-tub. The leading novelty of the present invention is the moveable system of shelves or trays, enclosed in metallic cases, separated by water, combined with the thermostatic regulator. By this combination, any quality of spii'its may be procured at one step from wash or wine, by an apparatus, simple, strong, and easily kept in order. The empyreumatic taint which spirits are apt to contract from the action of the naked fire on the bottom of the still, may be entirely prevented by the use of a bath of potash ley, p, py fig. 1365 ; for thus a safe and effectual range of temperature, of 300° F., may be conveniently obtained. The still may also be used without the bath vessel. Mr. D. T. Shears, of Southwark, obtained a patent in March, 1830, for certain im- provements and additions to stills, which are ingenious. They are founded upon a previous patent, granted to Joseph Corty, in 1818 ; a section of whose contrivance is •hown in fig, 1370, consisting of a first still a, a second still 6, a connecting tube c, from the one end to the other, and the tube d, which leads 1370 from the second still-head down through the bent tube / f'TU^f****^ *» *' '® ^^* lower part of the condensing apparatus. ' ^ The original improvements described under Corty's patent, consisted further, in placing boxes /,/,/> of the condensing apparatus in horizontal positions, and at a distance from each other, in order that the vapor might ascend through them, for the purpose of discharging the spirit by the top tube g, and pipe /i, into the worm, in a highly recti- fied or concentrated state. In each of the boxes/, there is a convex plate or inverted dish t, t, i, and the vapor ia rising from the tube 4^ strikes against the con- cave or under part of the first dish, and then escapes round its edges, and over its convex sur- face, to the under part of the second dish, and so on to the top, the eondeased part of the vapor flowing down again into the still, and the spirit passing oflT by the pipe h, at top ; and as the process of condensation will be assisted by cooling the Tapor as it rises, cold water is made to flow over the tops of the boxes /, from a cock k, and through small channels or tubes on the sides of the boxes, and is ultimately discharged by the pipe I, at bottom. Fig. 1371 represents a peculiarly shaped tube a, through which the spirit is described as passing after leaving the end of the worm at 6, which tube is open to the atmospheric 742 STILL. STILL. 743 # Now the improvements claimed under the present oatent are PTh;K;»«^ ;„ ^^. iiro 1373 and 1374 Fig. 1372. represents the 'externaftpearincT'o^a stUl^t^he h^S of Str.X l^TirZT'^'' guard against over-boiJing by any mislnagemenl ? J^ .if'^*^:i ^i^j^® same, partly m section. On the top of the still-head is formed the first^escribed rectifying apparatus, or series of condensing £^esTh" vapor from the body of the still filling the head, meets with the first check fr^m !he Sh or lower vessel i, and aUer passing under its edges, ascends and strikes SainTt^helowe- ^pl tZ " ''"'' '' '"' '' "* '^ it ultimately leal; tLft""tadbyT^^^^ This part of the apparatus is slightly altered from the former, by the substitution ol hollow convex vessels, instead of the inverted dishes before described, whicrveselsLv nms descending from their under surfaces, for the purpose of r^tainfng the va^r The cold water, which, as above described, flowed over the tops of the bofes/ forThe purpose of cooling them, now flows also through the hollow convex vessels t^^j^'thin the boxes, and by that means greatly assists the refrigerating process^by which thTaqueiSs ?^'^\^^'^Y^l^l^remore readily condensed, and made to fall do^na^d flow back a^L^ Lthttrof^i^^riii^^'"^ ''' ''''^^- ^-'' ^- «^- -p - ^'^ wr.! inVi:;? rntfthesUlV ^!|f,'^^'.^^^--^^ in which the wash is placed ^ei^ouITntr^^^^^^^^^ Sit h! K ; 7^^ P'P^ '"^ " *^^'^'^ "''""^ *" *^^ ^°we^ part of the vessel «, in order heat hv ^nni'** "^f^'' may communicate its caloric to the wash, instead VlUUThc heat by allowing the water to flow away. After the heated water has made several turns round the wash heater, it passes out at the curved pipe o which iTbentunh^ order to keep the coils of the pipe within always full of water ^' the horwater'?n,nf 1 ^'f "? ^^^ described the patentee pr'oposes sometimes to pass w!ch . T t Ta ^ «*'*'P'>«';i» a tub or wooden vessel, as at n, in fig. 1369, in which the ;;rn\^''htrx"ra«i;L^„"''^' ^''" •"■""= --' «»" *» -p-'^i '^»'» ""= -owe: The swan-neck h, fig, 1372 and 1373, which leads from Ihe head of the still conduct. spirit passes to the worm tub, and being finally con- ^ — T^ ^t^ densed, is passed through a safety tube, as (fig. 1366) / \y\ ^u ^372 before described, and by the funnel is conducted into ^ ^"''^ the cask below. Should any spirit nse m the wash-heater during the above operation, it will be carried down to the worm by the neck ;,, and coiled pipe, and discharged at its lower end^o^k may be passed into the still-head, as shown in^g! 1370. * ' ** Coffejf^i Still This ingenious, ori^ginal and powerful apparatus for distilling spirits from fermented worts or wash of all kinds, is, after many^^struggles with the illiberS prejudices of the Excise now universally recognized as the besfraost economica and surest m a revenue point of view, of all the contrivances of eliminating the alcohil in the purest state, and of any desired strength, at one operation. Its outer form ind internal structure differ essentially from those of all the old stills, though it possesses some of the good principles of Derosnes, m continuity of action, and in causing a currenl of spirituous vapor to ascend, and a current of wash deprived of its alcohol to descend in one system of continuous cells. Its main structure consists of a series of wooden planks, 6 or 6 inches thick, fixed over one another, the joints being covered, or the whole being lined with sheet copper; so that the apparatus resembles a great ches^ to which is attached the induction pipe of a steam boiler, as the active principle of the whole. The essential apparatus consists of three main parts; the wash collector a, a, a, and the two rectangular columns or uprights. The front column d, d, d, or the analyser, is for rectifying the wash, the other column is intended for warming the wash ; the under part f, f, f, of the forewarraer serves as ft dephlegmator and for the rectification of the feints; the upper part e, b, Ki serves to condense the strong spirituous vapor. 1376 The wash collector a, is divided into two compartments b and o, by means of the copper plate c c; this plate c c, is pierced with a drainer, with a number of small holes, and is provided also with a t shaped valve o o o. The wash rectifier d is divided by the plates r, r, of a like drainer construction into 12 chambers, and the feint rectifier F f, into 10 chambers by similar plates s, «, «. These orifices are so narrow as to allow the passage of the rising vapor, but to prevent the downward passage of the liquid resting on the plates, which passes downwards through the adjunct tubes, viz., d, into the wash collector b, v, into the rectifier d, and likewise into the dephlegmator f, pass- ing from each upper into the next under chamber. When the steam pressure is too strong, the valves o, o, give it vent When the apparatus is in action, a continuous stream of wash is raised out of o, by means of the pump k, into the tube t, which feeds the still. This current must be re- gulated very nicely, so as just to feed the tube », allowing the excess to return through the stop-cock ar, and the tube I, into the wash-cistern a The tube t enters into the uppermost partition of e, forming 7 zig-zag bendings in this space, and through f, and then mounts upwards from that chamber into the top chamber of d. Thence the wash flows down from chamber to chamber, and arrives through d into c, and finally in a similar way into b, where it is fully deprived of spirit, and is from time to time run off through t. It is necessary throughout that the wash in this passage into d and b should stand about an inch high upon each plate r r, for which purpose the adjunct tubes • 744 STILL. STILL. should stand an inch aboye the plate, and thus give the vapor no indirect passage, aa the under end of each tube v dips into a shallow cup, and is thus shut in by the wash remaining in it The tube d, which leads the wash from the plate c c into c, serves a Jike purpose. As soon as it has risen up in it to the upper orifice of the glass tube y. the valve 6 is to be opened, to allow it to flow off into b through the tube 6 Here into b the very hot and nearly spent wash comes into contact with' the steam issuing fi-om the steam boiler through tlie steam tube a, a. It rushes through it. and carries <>ff from it the spirit through the small orifices of the plate c, expands thus into the whole breadth of this chamber through the wash standing in it, and deprives this at once of every trace of spirit^ then collects over the fluid, and enters through the connec- tion tube c, into the undermost chamber of d, and thence into the following in succession always through the orifices of the plate r r. Whilst the steam meets the wash in even? •hamber and becomes more spirituous the higher it mounts, it at the same time becomes cooler, and deposites the watery part, absorbing more alcohol, so that after this compli- cated rectification it passes on through the tube m, wi, into the lowest chamber of the lorewarmer r It here pursues a like path upwards through the plates », «, where the feints are at the same time rectified by the dephlegmation of the vapor. The steam flows through the different junction tubes into f, and its subdivisions, whereby (as the wash in D) forms upon each plate a layer an inch thick to be penetrated by tlie steam. Ihe remainder passes out of the undermost plate through the tube g g, into g, where it 18 carried on by the pump with fresh wash into circulation in the apparatus. Ihe alcoholic vapors reaches now b. The plate which separates b and f is not per- forated ; it lets the vapor merely pass through the short and wide junction tube w, into tne condenser e, where in like manner the non-perforated plates w, w, compel it to fol- low the zig-zag bendings of i, i, so as to complete its condensation and the heating of llie wash in r. The completely condensed vapor is collected on the bottom of e, and 18 conducted out of the cup of the junction tube there, which is larger) through the annexed tube sideways at p, into the refrigerator, (not shown in the figure! 1 shall conclude this article with a description of two stills, the first of which is com- monly employed by the chemists in Berlin for rectifying alcohol, a, is the ash-pit; b. the fireplace ; c, c, the flues, which go spirally round the sides of the cucurbit , a. & b. of /£aLes a^^3ng t^e sfrai^h^SS'^'S^^ ^V?";."^x^ the second annular flue a a, as also in thTthird ? / th?fl« J /^l-O' *?^/»'/*- I" being separated from th?' fdjoinirg."; tL''st^^^^^^^^^ ^^^^ Wh'flt :iCe flames again come together, as also in o, and ascend by t^e middle oSnirB^sidp! ^^^^ 1380 flames into the upper space u which is usually left empty. These vents can be closed by iron damper-plates, pushed in through the slide-slits of the dome, t, t, are peei> ttkid'un X"?4^l''''''1-'^r^^^^^ ^"^ '^^y^^' mo'st'comn^^n^ bricked up. Mff. 381 is a vertical section, and Jig. 1382 a plan, o( an excellent kiln for baking clay to a stony consistence, for the above purpose, or for burning fire briok^ 1881 1882 ch mney kT a\te™^^^^^^^^^ ^°?. ^' *^« ^-^. terminating in the with a/iron doo; c. d, L tfe peep ho e fiZ"J' ^f.'"^?^ ""' '^' ^'^''' ^' >'« ^«^ered /,/ a vent in the middle of earha^rch^ifl with a clay stopper; ., is the fire-place; tween the two fireplaces i if ^11 .J'/' ^"f ^^ *^^ ^'^^« ^^ ^^^ a*"«he8. situated be- ;, a grate f^r the^ll^he^^^^^^^^^ to be baked; ings through which the flamesof a second fiL^Ufk *^^"P^' '*' ^h^ fire-door; o, open- kiln . . fifed. wUa deft biUets of ^CwVoS! traS Tt thto^l^S^^rrt^K STOVE. 749 Ib finished, the second is fired ; and then the third in like manner. This kiln is very like the porcelain kiln of Sevres, and is employed in many cases for baking stoneware. Mr. Keene obtained a patent a few years ago, for making a factitious stone-paste in the following way: — He dissolves one pound of alum in a gallon of water, and in this solution he soaks 84 pounds of gypsum calcined in small lumps. He exposes these lumps in the open air for about eight days, till they became apparently dry and then calcines them in an oven at a dull-red heat The waste-heat of a coke oven ia well adapted for this purpose. (See Pitcoal, coking of.) These lumps, being ground and sifted, afford a fine powder, which, when made up into a paste with the proper quantity of water, forms the petrifying ground. The mass soon concretes, and after being brushed over with a thin layer of the petrifying paste, may be polished with Eumice, Ac, in the usual way. It then affords a body of great compactness and dura- ility. If half a pound of copperas be added to the solution of the alum, the gypsum paste, treated as above, has a fine cream or yellow color. This stone stands the weather tolerably well. STONEWARE {Fayence Fr. ; Steingut Germ.) See Pottery. STORAX, STYRAX, flows from the twigs and the trunk of the Liquidamher ityracijlua, a tree which grows in Louisiana, Virginia, and Mexico. Liquidamber, aa this resin is also called, is a brown or ash-gray substance, of the consistence of turpen- tine, which dries up rapidly, has an agreeable smell, like benzoin, and a bitterish, sharp, burning taste. It dissolves in four parts of alcohol, and affords 1-4 per cent of benzoic acid. STOVE (Poelej Calorifdre, Fr. ; O/en^ Germ.), is a fire-place, more or less close, foi warming apartments. When it allows the burning coals to be seen, it is called a stove- grate. Hitherto stoves have rarely been had recourse to in this country for heating our sitting-rooms ; the cheerful blaze and ventilation of an open fire being generally prefer* red. But last winter, by its inclemency, gave birth to a vast multitude of projects for increasing warmth and economizing fuel, many of them eminently insalubrious, by pre- senting due renewal of the air, and by the introduction of noxious fumes into it. When coke is burned very slowly in an iron box, the carbonic acid gas which is generated, being half as heavy again as the atmospherical air, cannot ascend in the chimney at the temperature of 300° F. ; but regurgitates into the apartment through every pore of the stove, and poisons the atmosphere. The large stoneware stoves of France and Germany are free from this vice ; because, being fed with fuel from the outside, they cannot pro- duce a reflux of carbonic acid into the apartment, when their draught becomes feeble, as inevitably results from the obscurely burning stoves which have the doors of the fire-place and ash-pit immediately above the hearth-stone. I have recently performed some careful experiments upon this subject, and find that when the fuel is burning so slowly in the stove as not to heat the iron surface above the 250th or 300th degree of Fahr., there is a constant deflux of carbonic acid gas from the ash-pit into the room. This noxious emanation is most easily evinced by applying the beak of a matrass, containing a little Goulard's extract (solution of subacetate of lead), to a round hole in the door of the ash-pit of a stove in this languid state of combustion. In a few seconds the liquid will become milky, by the reception of carbonic acid gas. I shall be happy to afford ocular demonstration of this fact to any incredulous votary of the pseudo-economical, anti-ventilation stoves, now so much in vogue. There is no mode in which the health and life of a person can be placed in more insidious jeopardy, than by sitting in a room with its chimney closed up with such a choke-damp-vomiting stove. That fuel may be consumed by an obscure species of combustion, with the emission of very little heat, was clearly shown in Sir H. Davy's Researches on Flame, « The facts detailed on insensible combustion," says he, " explain why so much more heat is obtained from fuel when it is burned quickly, than slowly ; and they show that, in all cases, the temperature of the acting bodies should be kept as high as possible ; not only because the general increment of heat is greater, but likewise because those combinations are prevented, which, at lower temperatures, take place without any considerable production of heat. These facts likewise indicate the source of the great error into which experi- menters have fallen, in estimating the heat given out in the combustion of charcoal ; and they indicate methods by which the temperature may be increased, and the limits to certain methods." These conclusions are placed in a strong practical light by the follow- ing simple experiments:—! set upon the top orificeof a small cylindrical stove, a hemis- pherical copper pan, containing six pounds of water, at 60° F., and burned briskly under it three and a half pounds of coke in an hour; at the end of which time, four and a half pounds of water were boiled off. On burning the same weight of coke slowly in the same furnace, mounted by the same pan, in the course of twelve hours, little more than one half the quantity of water was exhaled. Yet, in the first case, the aerial products - ■ l^J! I , 750 1883 STOVE. of combustion swept so rapidly over the bottom of tb« pan, as to communicate to it not more than one-fourth of the effective heat which might have been obtained by one of the plans described in the article Evaporation ; while in the second case, these products moved at least twelve times more slowly across the bottom of the pan, and ought therefore to have been so much the more effective in eva- poration, had they possessed the same power or quantity of heat. Stoves, when properly constructed, may be employed both safely and advantageously to heat entrance-halls upon the ground story of a house ; but care should be taken not to vitiate the air by passing it over ignited surfaces, as is the case with most of the patent stoves now foisted upon the public. Fig. 1383 exhibits a vertical section of a stove which has been recommended for power and econo- my; but it is highly objectionable, as being apt to scorch STOVE. 751 the air. The flame of the fire a, the horizontal pipes of cast-iron, 6, 6, c, c, (2, d. circulates round e, e, which receive the external air at the orifice b, and conduct it up through the series, till it issues highly heated at k, l, and may be thence eonducted wherever it is wanted. The smoke escapes through the chimney b. This ttove has evidently two prominent faults; first, it heats the air-pipes very unequally, and the undermost far too much ; secondly, the air, by the time it has ascended through the zigzag range to the pipe e e, will be nearly of the same temperature with it, and will therefore abstract none of its heat. Thus the upper pipes, if there be several in the range^ will be quite inoperative, wasting their warmth upon the sooty air. Fig, 1074 exhibits a transverse vertical section of a far more economical and powerful Itove, in which the above evils are avoided. The products of combustion of the fire a, 1383 ^..,r-^sg; ^^' to dyeing. Blue is given by a boiling-hot solution of indigo in sulphuric acid, called Saxon bitte, diluted to the desired shade ; yellow, by de- coction of turmeric ; red, by boiling hanks of coarse scarlet wool in a bath of weak alum water, containing the straw ; or directly, by cochineal, salt of tin, and tartar. Brazil wood and archil are also employed for dyeing straw. For the other colors, see their re- spective titles in this Dictionary. STREAM-WORKS. The name given by the Cornish miners to alluvial deposits cf tin ore, usually worked in the open air. STRETCHING MACHINR Cotton goods and other textile fabrics, either white or t)rinted, are prepared for the market by being stretched in a proper machine, which ays all their warp and woof yarns in truly parallel positions. A very ingenious and effective mechanism of this kind was made the subject of a patent by Mr. Samuel Mo- rand, of Manchester, in April, 1834, which serves to extend the width of calico piecei^ or of other cloths woven of cotton, wool, silk, or flax, after they have become shrunk in the processes of bleaching, dyeing, >? '"'''=" ">e ™latile pariides are raised bv h».t «.d condensed into . crjstalline mass. See CAWM^t and slr I^otrAc! for^JlSI: leaT^^"' '' " "" '" "'■'"' "" ■"'* '^ "»' «"»"'«' "i* «Wi as subacetate d pj?;=^ ''^-rrb itrr^fe dts:l ?Sr iS5 nr^n.u 7^^'* f""*,'- ^'''^'.\^f':^-)y is the sweet constituent of vegetable and animal products. It may be distinguished into two nrincinal «;npriP«! Th^ fi «♦«,>.• T *"™r SUGAR. 755 by 100 ; and in circumpolarization it bends the luminous rays to the right The second occurs ready formed in ripe grapes and other fruits; it is also produced by treating starch with diastase or sulphuric acid. This species forms cauliflower concretions, but not true crystals; it has a sweetening power which may be represented by 60, and in circumpolarization it bends the rays to the left Besides these two principal kinds of sugar, some others are distinguished by chemists ; as the sugar of milk, of manna, of certain mushrooms, of liquorice-root, and that obtained from sawdust and glue by the action of sulphuric acid ; but they have no importance in a manufacturing point of view. Sugar, extracted either from the cane, the beet, or the maple, is identical in its pro- perties and composition, when refinti to the same pitch of purity ; only that of the beet seems to surpass the other two in col esive force, since larger and firmer crystals of it are obtained from a clarified solution of equal density. It contains 5*3 per cent, of combined water, which can be separated only by uniting it with oxyde of lead, into what has been called a saccharale; made by mixing sirup with finely ground litharge, and evaporating the mixture to dryness upon a steam-bath. When sugar is exposed to a heat of 400* F., it melts into a brown pasty mass, but still retains its water of composition. Sugai thus fused is no longer capable of crystallization, and is called caramel by the French. It is used for coloring liqueurs. Indeed, sugar is so susceptible of change by heat, that if a colorless solution of it be exposed for some time to the temperature of boiling wa- ter, it becomes brown and partially uncrystallizable. Acids exercise such an injurious influence upon sugar, that after remaining in contact with it for a little while, though they be rendered thoroughly neutral, a great part of the sugar will refuse to crystallize. Thus, if three parts of oxalic or tartaric acid be added to sugar in solution, no crys- tals of sugar can be obtained by evaporation, even though the acids be neutralized by chalk or carbonate of lime. By boiling cane sugar with dilute sulphuric acid, it is changed into starch sugar. Manufacturers of sugar should be, therefore, particularly watchful against every acidulous taint or impregnation. Nitric acid converts sugar into oxalic and malic acids. Alkaline matter is likewise most detrimental to the grain of •ugar ; as is always evinced by the large quantity of molasses formed, when an excess oi temper lime has been used in clarifying the juice of the cane or the beet. When one piece of lump sugar is rubbed against another in the dark, a phosphorescent light is emitted. Sugar is soluble in all proportions in water ; but it takes four parts of spirits of wine, of spec. grav. 0-830, and eighty of absolute alcohol, to dissolve it, both being at a boiling temperature. As the alcohol cools, it deposites the sugar in small crystals. Caramelized and uncrystallizable sugar dissolves readily in alcohol. Pure sugar is unchangeable in the air, even when dissolved in a &Jod deal of water, if the solution be kept covered and in the dark ; but with a very small addition of gluten, the solution soon begins to fer- ment, whereby the sugar is decomposed into alcohol and carbonic acid, and ultimately into acetic acid. Sugar forms chemical compounds with the salifiable bases. It dissolves readily ii caustic potash ley, whereby it loses its sweet taste, and aflbrds on evaporation a mast which is insoluble in alcohol. When the ley is neutralized by sulphuric acid, the sugar recovers its sweet taste, and may be separated from the sulphate of potash by alcohol, but it will no longer crystallize. That sirup possesses the property of dissolving the alkaline earths, lime, magnesia, Btrontites, barytes, was demonstrated long ago by Mr. Ramsay of Glasgow, by experi- ments published in Nicholson's Journal, volume xviii. page 9, for September, 1807. He found that sirup is capable of dissolving half as much lime as it contains of sugar ; and as much strontites as sugar. Magnesia dissolved in much smaller quantity, and barytes, seemed to decompose the sugar entirely. These results have been since confirmed by Professor Daniell. Mr. Ramsay characterized sugar treated with lime as weak, from its sweetening power being impaired; from its solution he obtained, after some time, a deposite of calcareous carbonate. M. Pelouze has lately shown, that the carbonic acid in this case is derived from the atmosphere, and is not formed at the expense of the ele- ments of the sugar, as Mr. Daniell had asserted. Sugar fornus with oxyde of lead two combinations ; the one soluble, the other insolu- ble. Oxyde of leau digested in sirup dissolves to a certain amount^ forms a yellowish liquor, which possesses an alkaline reaction, and leaves after evaporation an uncrystalli- zable, viscid, deliquescent mass. If sirup be boiled with oxyde of lead in excess, if the solution be filtered boiling hot, and if the vial be corked in which it is received, white bulky flocks will fall to its bottom in the course of 24 hours. This compound is best dried in vacuo. It is in both cases' light, tasteless, and insoluble in cold and boiling water ; it takes fire like German tinder, (Amadou,) when touched at one point with an ignited body, and burns away, leaving small globules of lead. It dissolves in acids, and also in neutral acetate of lead, which forms with the oxyde a subsalt, and sets the sugar 756 SUGAK. SUGAR. 757 free. Carbonic acid gas passed through water in which the above saccharate is diffused, decomposes it, with precipitation of carbonate of lead. It consists of 58*26 parU of oxide of lead, and 41-74 sugar, in 100 parts. From the powerful action exercised upon sugar by acids and oxyde of lead, we may see the fallacy and danger of using these chemical reagents m sugar-refining. Sugar possesses the remarkable property of dissolving the oxyde, as well as the subacetate of copper, (verdigris,) and of counteracting their pois( ous operation. Orfila found that a dose of verdigris, which would kill a do«' in an bo or two, might be swallowed with impunity, provided it was mixed with a considera) quantity of sugar. When a solution of sugar is boiled with the acetate of copper, it caus an abundant precipitate of protoxyde of copper ; when boiled with the nitrates of mercu •nd silver, or the chloride of gold, it reduces the respective bases to the metallic state. The following Table shows the quantities of Sugar contained in Sirups of the annexe ipecific gravities.* It was the result of experiments carefully made. Experimental specific ^ra- Tity of solution at 60' F. Sugar in 100, by weight. Experimental specific gra- vity of solution at 60° F. Sugar in 100, by weight. 1-3260 1-2310 1-1777 1-4400 1-1340 M250 1-1110 66-666 50000 40-000 33-333 31-250 29-412 26-316 1-1045 1-0905 1-0820 1-0685 1-0500 1-0395 25-000 21-740 20-000 16-666 12-500 10000 If the decimal part of the number denoting the specific gravity of sirup be multiplied by 26, the product will denote very nearly the quantity of sugar per gallon in pounds weight, at the given specific gravity .f Sugar has been analyzed by several chemists; the following Table exhibits some of Iheir results : — Gay Lussac and Thenard. Berzelius. Prout. Ure. Oxygen, - - Carbon, - - - Hydrogen, - - 56-63 42-47 6-90 49-856 43-265 6-875 53-35 39-99 6-66 50-33 43-38 6-29 in 100. Of the mpar cane, and the extraction of sugar from it. — Humboldt, after the most elaborate historical and botanical researches in the New World, has arrived at the con- clusion, that before America was discovered by the Spaniards, the inhabitants of that continent and the adjacent islands were entirely unacquainted with the sugar can^, with any of our corn plants, and with rice. The progressive diffusion of the cane has been thus traced out by the partisans of its oriental origin. From the interior of Asia it wat transplanted first into Cyprus, and thence into Sicily, or possibly by the Saracens di- rectly into the latter island, in which a large quantity of sugar was manufactured iu the year 1 148. Lafitau relates the donation made by William the Second, king of Sicily, to the convent of St Benoit, of a mill for crushing sugar canes, along with all its priv- il^es, workmen, and dependencies: which remarkable gift bears the date of 1166. According to this author, the sugar cane must have been imported into Europe at the period of the Crusades. The monk Albertus Aquensis, in the description which he has given of the processes employed at Acre and at Tripoli to extract sugar, says, that in the Holy Land, the Christian soldiers being short of provisions, had recourse to sugar canes, which they chewed for subsistence. Toward the year 1420, Dom Henry, regent of Portugal, caused the sugar cane to be imported into Madeira from Sicily. This plant succeeded perfectly in Madeira and the Canaries ; and until the discovery of America these islands supplied Europe with the greater portion of the sugar which it consumed. The cane is said by some to have passed from the Canaries into the Brazils; but by others, from the coast of Angola in Africa, where the Portuguese had a sugar colony. It was transported in 1506, from the Brazils and the Canaries, into Hispaniolaor Haytij where several crushing-mills were constructed in a short time. It would appear, * ^? author, in minutes of evidence of Molasses Committee of the House of Commons, 1831, p. 143L t This rule was annexed to an extensive table, representing the quantity of sugar per gallon corre. spondmg to the specific gravities of the syrup, constructed by the author of the Excise, in subserviency to the Bee^root Kll. "' moreover, from the statement of Peter Martyr, in the third book of his first Decade, written during the second expedition of Christopher Columbus, which happened between 1493 and 1495, that even at this date the cultivation of the sugar cane was widely spread in St. Domingo. It may therefore be supposed to have been introduced here by Co- lumbus himself, at his first voyage, along with other productions of Spain and the Canaries, and that its cultivation had come into considerable activity at the period of his second expedition. Towards the middle of the 17th century, the sugar cane was imported into Barbadoes from Brazil, then into the other English West Indian possessions, into the Spanish Islands on the coast of America, into Mexico, Peru, Chile, and, last of all, into the French, Dutch, and Danish colonies. The sugar cane, jirundo saccharifera, is a plant of the graminiferous family, which varies in height from 8 to 10, or even to 20 feet. Its diameter is about an inch and a half; its stem is dense, brittle, and of a green hue, which verges to yellow at the approach of maturity. It is divided by prominent annular joints of a whitish-yellow color, the plane of which is perpendicular to the axis of the stem. These joints are placed about 3 inches apart ; and send forth leaves, which fall off with the ripening of the plant. The leaves are 3 or 4 feet long, flat, straight, pointed, from 1 to 2 inches in breadth, of a sea- green tint, striated in their length, alternate, embracing the stem by their base. They are marked along their edges with almost imperceptible teeth. In the 11th or 12th month of their growth, the canes push forth at their top a sprout 7 or 8 feet in height, nearly half an inch in diameter, smooth, and without joints, to which the name arrow is given. This is terminated by an ample panicle, about 2 feet long, divided into several knotty ramifications, composed of very numerous flowers, of a while color, ajvetalous, and furnished with 3 stamens, the anthers of which are a little oblong. The roots of the sugar cane are jointed and nearly cylindrical; in diameter they are about one twelfth of an inch ; in their utmost length 1 foot, presenting over their surface a few short radicles. The stem of the cane in its ripe state is heavy, very smooth, brittle, of a yellowish- violet, or whitish color, according to the variety. It is filled with a fibrous, Spongy, dirty-white pith, which contains very abundant sweet juice. This juice is elaborated separately in each internodary portion, the functions of which are in this respect inde- pendent of the portions above and below. The cane may be propagated by seeds of buds with equal facility; but it is usually done by cuttings or joints of proper lengths, from 15 to 20 inches, in proportion to the nearness of the joints, which are generally taken from the tops of the canes, just below the leaves. There are several varieties of the sugar-cane plant. The first, and longest known, if the Creole, or common sugar cane, which was originally introduced at Madeira. It grows freely in every region within the tropics, on a moist soil, even at an elevation of 3000 feet above the level of the sea. In Mexico, among the mountains of Caudina- Masca, it is cultivated to a height of more than 5000 feet. The quantity and quality of sugar which it yields, is proportional to the heat of the place where it grows, provided it be not too moist and marshy. The second variety of this plant is the Otaheilan cane. It was introduced mto the West Indies about the end of the 18th century. This variety, stronger, taller, with longer spaces between the joints, quicker in its growth, and much more productive in susar, succeeds perfectly well in lands which seem too much impoverished to grow the ordinary cane. It sends forth shoots at temperatures which chill the growth and develop- ment of the Creole plant. Its maturation does not take more than a year, and is accom- plished sometimes in nine months. From the strength of its stem, and the woodiness of its fibres, it better resists the storms. It displays a better inflorescence, weighs a third more, affords a sixth more juice, and a fourth more sugar, than the common variety. Its main advantage, however, is to yield four crops in the same time that the creole cane yields only three. Its juice contains less feculency and mucilage, whence its sugar is more easily cr^'stallized, and of a fairer color. Besides these two varieties, another kind is described by Humboldt and Bonpland, under the name of the violet sugar-cane, for its haum and leaves are of this color. It was transported from Batavia in 1782. It flowers a month sooner than the rest, that is, in August, but it yields less solid sugar, and more liquid, both of which have a violet tint. In saying that the cane may be propagated by seeds as well as buds, we must remark that in all the colonies of the New World, the plant flowers, indeed, but it then sends forth a shoot (arrow), that is, its stem elongates, and the seed-vessel proves abortive. For this reason, the bud-joints must there be used for its propagation. It grows to seed, however, in India. This circumstance occurs with some other plants, which, when pro- pagated by their roots, cease to yield fertile seeds ; such as the banana, the bread-fruit, the lily, and the tulip. In the proper season for planting, the ground is marked out by a line into rows three or four feet asunder, in which rows the canes are planted about two feet apart. The r58 SUGAR. f !l ! lll^V/ ^ir^^^ "'**'. P'®''^^ ""^ ^^"^ 60 or 70 feet broad, learing spaces of about 20 feet, for the convenience of passage, and for the admission of sun and air between the stems. Canes are usuaUy planted in trenches, about 6 or 8 inches deep, made with the hand-hoe, the raised soil being heaped lo one side, for covering-in tht WrLTifJ A^ • *^\^°^^* ^ negro drops the number of cuttings intended to be IZf. .kA-11 ^^if*"^ ^k";? Pf ^°""^,.by other negroes. The earth is then drawn about the hillocks with the hoe. This labor has been, however, in many places better and more cheaply performed by the plough ; a deep furrow being made, into which the cuttings are regularly planted, and the mould then properly turned in. !L M if '*""? »'' *** }^ afterwards kept clear by the horse-hoe, the rows of canes should be feet asunder, and the hillocks 2$ feet distant, with only one cane left in one hillock. After some shoots appear, the sooner the horse-hoe is used, the more wiU the plants thrive by keeping the weeds under, and stirring up the soil. Plant-canes 01 the first growth have been known to yield, on the brick-mould of Jamaica, in very fine seasons 2i tons of sugar per acre. The proper season for planting the cane slips, containing he buds, namely, the top part of the cane, stripped of its leaves, and the two or three upper joints, is m the interval between August and the beginning of ^nnlfJ? tn'*>, ^*''?K^ ^^ the autumnal weather, the young plants become luxuriant enough to shade the ground before the dry season sets in; thereby keeping the roots cool and moderately moist. By this arrangement the Creole canes are ripe for the miU in the beginning of the second year, so as to enable the manaser to finish his crop early ^J.l^^:r I '^ ""u ^""f ^l' ^"■°'" '"^ ^^^ *^°^«"»^^ ^^*^ Pl«"ting canes at an improper season of the year, whereby his whole system of operations becomes disturbed, and, in « certain degree, abortive. > * ^ The withering and fall of a leaf aflford a good criterion of the maturity of the cane- joint to which It belonged ; so that the eight last leafless joints of two canes, which are cut the same day have e:cactly the same age and the same ripeness, though one of the canes be 15 and the other only 10 months old. Those, however, cut towaAs the end of the dry season, before the rains begin to fall, produce better sugar than those cut in the rainy season as they are then somewhat diluted with watery juice, and require more eva- poration to form sugar. It may be reckoned a fair averaee product, when one pound of sugar is obtained from one gallon (English) of juice. - *- ' r- u. Rattoons (a word corrupted from rejettons) are the sprouts or suckers that spring from the roots or stoles of the canes that have been previously cut for sugar. They are thTrr"Jf "PJ '"^ 12 months ; but canes of the first growth are called plant-canes, being Innir ntvl?^^ • '^^ ^"^'"^^ '""-'"^^ "'' ^^™^ P^^^^^ ^^ ^he grouud, and require I lrP^.,7n ^«*>""?;h/™ to maturity. The first yearly return from the roofs that nn ,. nrT^"' T fh • ^''^ rf toons; the second year's growth, second rattoons; and so on, according to their aije. Instead of stocking up his rattoons, holing, and planting ^^.^k\VZ''^'"''I^T^'''^'\^^ ^i°'"^ *° continue in the 'ground/ and SenJ himself, as the cane fields become thin and impoverished, with supplying the vacant nlacei With fresh plants. By these means, and with the aid V manure,\he pr^uce of su 'S per acre, if not apparently equal to that from plant-canes, gives perhaps in the Ion- run as great returns to the owner, considering the relative proportion of the labor and expense attending the different systems. The common yielding on proper land, such as the rS soil of Trelawney, m Jamaica, is 7 hogsheads, of 1 6 cwts. each, to 10 acres of rattoong cZ annually ; and such a plantation lasts from 6 to 10 years. *«iioon8cui When the planted canes are ripe, they are cut close above the ground, by an oblique sec ion, into lengths of 3 or 4 feet, and transported in bundles to the mill-house Iflhe roots be then cut ofi; a few inches below the surface of the soil, and covered up with fine mould, they will push forth more prolific oflsets or rattoons, than when left projectinc in he common way. ^ "jc^^wug la The recent researches of the eminent French chemist, M. Casaseca, upon cane iuice «. fST"*K ' • ^"^'r ^r""^ demonstrated clearly the enormous loss which sugar-plan tew suffer by the imperfection of their manufacturing processes. His results confirm those previously obtained by M. Peligot in Paris, and^ Ihow that cane juice evatrTtedi^ \acuo at the atmospheric temperature yields, in 100 parts,— i^rateu la Crystalline white sugar - , . 20'94 Water - - . . - 78'80 Mineral substances - . . . q.-,a Organic matter, different from sugar - 0*12 The cane from which the above juice was drawn is called canade la tierra in Cuba. The juice of the Otaheite cane ,s identical with the preceding. But the proportions o^ Igneous fibres m the two canes are very different ; that of la tierra containing according to M. Casaseca, 16-4 per cent, while that of Otaheite contains only 10. (Hher canef however, differ in this respect considerably from these two varieties. The averaS quantity of grained sugar obtained from cane juice in our colonial plantations is proba Wy not more than one-third of the quantity of crystalline sugar in the juice which they boif SUGAR. 759 The following analysis of cane juice, performed by a French chemist, was given me by Mr. Forstall of New Orleans. In 10 English gallons, of 231 cubic inches each of juice making 8i° Baum6, there are 6f ounces English of salts, which consist of— Sulphate of potash - - 17*840 grammes— 16'44 grains each. Phosphate of potash - - 16-028 C^lorure of potassium - - 8"355 Acetate of potash - • - 63*760 Acetate of lime - - - 36*010 Gelatinous silica ... 15*270 167*153 ■«= 5*57 ounces avoirdupois To the large proportion of deliquescent saline matter, of which one half he says remains in the sugar, the analyst ascribes very properly the deliquescence and dete- rioration of the sugar when kept for some time or transported. It was probably the juice of the cane grown in the rich alluvial soil of Louisiana, and therefore more abun- dant in saline matter than the average soil of our West India Islands. The Demerara cane-juice has perhaps the above saline constitution, as it suffers much loss of weight by drainage in the home voyage. OF SUGAR MILLS. The first machines employed to squeeze the canes, were mills similar to those which serve to crush apples in some cider districts, or somewhat like tan-mills. In the centre of a circular area of about 7 or 8 feet in diameter, a vertical heavy wheel was made to revolve on its edge, by attaching a horse to a cross beam projecting horizontally from it and making it move in a circular path. The cane pieces were strewed on the some- what concave bed in the path of the wheel, and the juice expressed flowed away through a channel or gutter in the lowest part This machine was tedious and unpro- ductive. It was replaced by the vertical cylinder-mill of Gonzales de Velosa ; which has continued till modern times, with little variation of external form, but is now gen- erally superseded by the sugar-mill with horizontal cylinders. SpeciJicatioH of, and Observations on the Construction and Use of the best Horizontal Sugar-mill. Fly. 1385. Front elevation of the entire mill. Fig. 1386. Horizontal plan. Fig. 1387. End elevation. Fig. 1388. Diagram, showing the dispositions of the feeding and delivering rollers, feeding board, returner, and delivering board. Fig. 1385. a, a, solid foundation of masonry; b, b, bed plate: o, c, headstocks or standards; d, main 8haft(seenonly in/^. 1386); b, intermediate shaft ; f, f, plummer- blocks of main shaft d (seen only \v\jig. 1386); h driving pinion on the fly-wheel shaft of engine ; i, first motion mortise wheel, driven by the pinion ; k, second motion pinion, on the same shaft; l, second motion mortise-wheel, on the main shaft; m, brays of wood, holding the plummer-blocks for shaft d ; n, wrough^iron straps connecting the brays of the standards c, c; o, o. regulating screws for the brays; p, top roller and gudgeons; q and k, the lower or feeding and delivering rollers; s, clutch for the con- nection of the side of lower rollers q and r, to the main shaft (seen only mjig. 1386) ; T, T, the drain gutters of the mill-bed (seen only in^^. 1386). The same letters of reference are placed respectively on the same parts of the mill in each oijigs. 1385, 1386, and 1387. The relative disposition of the rollers is shown in the diagram,^. 1388, in which a is the top roller; b, the feeding roller; c, the delivering roller; d, the returner; e, the feed board ; f, the delivering board. The rollers are made 2^ inches to 2^ inches thick, and ribbed in the centre. The feeding and delivering rollers have small flanges at their ends (as shown in Jig 1385) between which the top roller is placed ; these flanges prevent the pressed canes or begass from working into the mill-bed. The feeding and top rollers are generally fluted, and sometimes diagonally, enabling them the better to seize the canes from the feed-board. It is, however, on the whole, considered better to flute the feeding roller onlv, leaving the top and delivery rollers plane; when the top roller is fluted, it should be very slightly, for, after the work of a few weeks, its surface becomes sufficiently rough to- bito the canes effectively. The practical disadvantage of fluting the delivering rollers; is in the groves carrying round a portion of liquor, which is speedily absorbed by the spongy begass, as well as in breaking the begass itself, and thus causing great waste. The feed board is now generally made of cast iron, and is placed at a considerable inclination, to allow the canes to slip the more easily down to the rollera The returner is also of cast iron, serrated on the edge, to admit the free flowing of the liquor to the mill-bed. The concave returner, formerly used, was pierced with holes to drain off the liquor, but it had the serious disadvantage of the holes choking up with the splinters of the cane, and has therefore been discarded. The delivering board is of cast iron, fitted close to the roller, to detach any begass that may adhere to it, and otherwise mix with the liquor. reei SUGAR. SUGAR. 761 r . J^^.^'^k'^™',,®"?"*"' Cayenne, and the alluvial district of Trinidad, it is oraal to ittacii to the mill a liquor-pump, with two barrels and three adjustments of stroke. Thit ffl! ■M b worked from the gudgeon of the top roller. In action, the liquor from the eutter of whicT eads toThVt -fi' '''''"^ '' ^'^ ^T *"^ '^' '^^'^ by ?he pump to thTgutti rarsinrDfnes arVl f S ""'.f^^^^''' ?"«»» P"^PS have brass barrels and copper dis- charging pipes, are worked with a very slow motion, and require to be carefully adiusted ^«.ffl?"^" f^ ''^■^T'" .'^ ^" '""'''^ ^^^'^h' ^ithou[ such p'ecaution% Slher not drall JuXuZi^y mill, the feeding roller is kept about half an inch distant from the upper •iher as little as possible. They are taken in by the feed rollers, which split and sHgh^ press them ; the liquor flows down, and, the returner guiding the canes between ine wp and delivering rollers, they receive the final pressure, and are turned out on the mill-floor, while the liquor runs back and falls into the mill-bed. The begass, then m the state of pithy adhering to the skin of the cane, is tied up in bundles, and after being exposed a short time to the sun, is finally stored in the begass-house for fuel. By an important improvement in this stage of the process, recently introduced, the begass is carried to the begass-house by a carrier chain, worked by the engine. The relative merits of horizontal and vertical sugar-mills on this construction may be thus slated:— The horizontal mill is cheaper in construction, and is more easily fixed; the process of feeding is performed at about one half of the labor, and in a much supe- rior manner; the returner guides the canes to receive the last pressure more perfectly; and the begass is not so much broken as in the vertical mill, but left tolerably entire, so as to be tied, dried, and stored, with less trouble and waste. The vertical mill has a considerable advantage, in being more easily washed ; and it can be readily and cheaply mounted in wooden framing ; but the great labor of feeding the vertical mill renders it nearly inapplicable to any higher power than that of about ten horses. In situations where the moving power is a windmill, or a cattle-gin, the vertical mill may be preferred. The scale of produce of such mills varies according to the climate and soil. In Deme- rara, a well-constructed engine and mill will produce about 100 gallons of liquor per hour for each horse power. The dimensions of the most approved horizontal mills are these : — Horae-powcr of Engine. Leng:th of Rollers. Diameter of Rollers. 8 10 12 ft. in, 4 4 6 4 8 , inches, 25 27 28 The surface speed of the rollers is 3*4 or 3*6 feet per minute ; and to provide for th« varying resistance arising from irregular feeding, or the accidental crossing of the canes, by which the engine is often brought up so suddenly as to break the fly-wheel shaft, it is necessary to make both the shaft and the fly-wheel of unusual strength and weight. Sugar is manufactured in the East Indies by two distinct classes of persons ; the ryoiSf who raise the sugar cane, extract its juice, and inspissate it to a sirupy consistence; and the goldarsy who complete the conversion into sugar. The ryots are the farmers, or actual cultivators of the soil ; but, properly speaking, they are merely peasants, toiling under oppressive landlords, and miserably ^ poor. After they cut the canes, they extract the juice by one ci other of the rude mills or mortars presently to be described, and boil it down to an entire mass, which is gene- rally called gooTf without making any attempt to clarify it, or separate the granular sugar from the uncrystallizable molasses. This goor is of various qualities ; one of 762 SUGAR. SUGAR. 763 i i« 1389 1 1 1 which, in roost common nse for making sugar, is known amongst the English settlert under the name of jaggery. There is a caste in Ceylon, called jaggeraros, whc make sugar from the produce of the Caryota t*re»w, or Kitui tree ; and the sugar if styled jaggery. Sugar is not usually made in Ceylon from the sugar cane ; but either from the juice of the Kitul, from the Cocos nuciferaf or the Borassus Jlabelliformis (the Palmyra tree.) Several sorts of cane are cultivated in India. The Cadjoolee (fig. 1389) is a purple-colored cane ; yields a sweeter and richer juice than the yellow or light-colored, but in less quantities, and is harder to press. It ?row8 in dry lands. When eaten raw, it is somewhat dry and pithy in the mouth, but is esteemed very good for making sugar. It is not known to the West India planter. The leaves rise from a point 6 feet above the ground. An oblique and transverse section of the cane is repre- sented by the parts near the bottom of the figure. The Pooree is a light-colored cane, yellow, inclining to white, deeper yellow when ripe and on rich ground. West India planters consider it the same sort as one of theirs. It is softer and more juicy than the preceding, but the juice is less rich, and produces a weaker sugar. It requires seven parts of pooree juice to make as much goor as is pro- duced from six of the cadjoolee. Much of this cane is brought to the Calcutta market, and eaten raw. The CuUorah thrives in swampy lands, is light-colored, and grows to a great height. Its juice is more watery, and yields a weaker sugar also than the cadjoolee. However, since much of Bengal consists of low grounds, and since the upland canes are apt to suffer from drought, it deserves encouragement in certain localities. It is only large farms that cut an acre of cane in a year ; one mill, therefore, and one set of the implements used in inspissating the juice, although very rude and simple, serve for several farms, and generally belong to some wealthy man, who lets them out for hire to his poorer neighbors, the whole of whom unite to clear each other*i fields by turns ; so that though many people and cattle are employed j T^f |IV \ at one of these miserable sets of works, very few indeed are hired* and the greater part of the labor is performed by the common stock of the farms. The inspissated juice, or extract of cane, called by the natives goor is of two kinds ; one of which may be termed cake extract, and the other pot extract ; both being often denominated jaggery, as above stated, by the English residents. One third of an acre of good land in the southern districts, is reckoned by the farmers to produce 18,891 pounds of cane, and 1,169 pounds of pot extract. Its produce in cake extract is about 952 pounds. I shall now describe the primitive rude mill and boi- ler used in preparing the extract of sugar cane, and which are usually let to the ryots by the day. The mill in Dinajpur,/g. 1080, is on the principle of a pestle and mortar. The pestle, how- ever, does not beat the canes, but is rubbed against them, as is done in DHiny chemical triturations ; and the moving force is two oxen. The mortar is gene- rally a tamarind tree, one end of which is sunk deep in the ground, to give it firmness. The part pro- , ^ , . . , jecting, a, a, a. a, mar be about two feet high, and a foot and a half in diameter ; and in the upper end » hollow is cut, like the small segment of a sphere. In the centre of this, a channel descends a little way perpendicularly, and then obliquely to one side of the mortar, 80 that the juice, as squeezed from the cane, runs oflT, by means of a spout 6, into a strainer c, through which it falls into an earthen pot, that stands in a hole d, under the spout. The pestle e, is a tree about 18 feet in length, and 1 foot in diameter, rounded at its bottom, which rubs against the mortar, and which is se- cured in its place by a button or knob, that goes into the channel of the mortar. The moving force is applied to a horizontal beam /, about 16 feet in length, which turns round about the mortar, and is fastened to it by a bent bamboo^ b. It is suspended from the upper end of the pestle by a bamboo g, which has been cut with part of the root, in which is formed a pivot that hangs on the upper point of the pestle. The cattle are yoked to the horizontal beam, at about ten feet from the mortar, move round it in a circle, and are driven by a man, who sits on the beam, to increase the weight of the triturating power. Scarcely any machine more miserable can be con- ceived ; and it would be totally ineffectual, were not the cane cut into thin slices. This is a troublesome part of the operation. The grinder sits on the ground, having before him a bamboo stake, which is driven into the earth, with a deep notch formed in its up- per end. He passes the canes gradually through this notch, and at the same time cuts oflf the slices with a kind of rude chopper. The boiling apparatus is somewhat better contrived, and is placed under a shed, though the mill is without shelter. The fireplace is a considerable cavity dug in the ground, and covered with an iron boiler p,fig. 1391. At one side of this, is an opening q, for throwing in fuel ; and opposite to this, is another opening, which communicates 1391 with the horizontal flue. This is formed by two parallel mud walls r, r, a, s, about 20 feet long, 2 feet high, and 18 inches distant from each other. A row of eleven earthen boilei s t, is placed on these walls, and the interstices «, are filled with clay, which completes the furnace-flue, an opening r, being left at the end, for giving vent to the smoke. The juice, as it comes from the mill, is first put into the earthen boiler that is most distant from the fire, and is gradually removed from one boiler to another, until it reaches the iron one, where the process is completed. The fireplace is manifestly on the same model as the boiler range in the West Indies, and may possibly have suggested it, since the Hindostan furnace is, no doubt, of immemorial usage. The execution of its parts is very rude and imperfect. The inspissated juice that can be prepared in 24 hours by such a mill, with 16 men and 20 oxen, amounts to no more than 476 lbs. ; and it is only in the southern parts of the district, where the people work night and day, that the sugar-works are so productive. In the northern districts, the people work only during the day, and inspissate about one half the quantity of juice. The average daily make of a AVest India sugar-house, is from 2 to 3 hogsheads, of 16 cwts. each. The Indian manufacturers of sugar purchase the above inspissated juice or goor from the farmers, and generally prefer that of a granular honey consistence, which is offered for sale in pots. As this, however, cannot conveniently be brought from a distance, some of the cake kind is also employed. The boilers are of two sizes ; one adapted for making at each operation about ten cwts. ; the other, about eight and a half. The latter is the segment of a sphere, nine feet diameter at the mouth ; the former is larger. The boiler is sunk into a cylindrical cavity in the ground, which serves as a fireplace, so that its edge is just above the floor of the boiling-house. The fuel is thrown in by an aperture close to one side of the boiler, and the smoke escapes by a horizontal chimney that passes out on the opposite side of the hut, and has a small round aperture, about ten feet distant from tb i wall, in order to lessen the danger from fire. Some manufac- turers have only one boiler ; others as many as four ; but each boiler has a separate hut, in one end of which is some spare fuel; and in the other, some bamboo stages, which support cloth strainers, that are used in the operation. This hut is about twenty-four cubits long, and ten broad ; has mnC walls,*ix cubits high ; and is raised about one cubit a1)ove the ground. For each boiler, two other houses are required : one in which the cane extract is separated by straining from the molasses, is about twenty cubits long by ten wide ; an- other, about thirty cubits long, by eight wide, is that in which, after the extract has been strained, boiled, and clarified, the treaciC is separated from the sugar by an operation an. alogous to claying. 764 SUGAR. SUGAR. 765 :iil{ ., bef ;? hiXleTr'^"'''''"' ^^ ^ """^'^""'^ ^''^''' "*' * ^^« proportional to the nam. About 960 pounds of pot extract being divided into four parts, each is nut into a ba< • ^r"'-' iff^^'^°>K' ^';"^. ^^^' ^"^ ^^"^^ """^^^^ °^ wide-mouthV earthen ie^els a3 ,s besprinkled with a htl e water. These drain from the bags about 24? noTnds ofl substance analogous to West Indian molasses. The remainde? in the ba-s La kind of coarse muscovado sugar; but is far from beine so well drainpH «n^ a. i^^r , »«! that nfthp. Antni^r Vk^ -yon i WliT-^ &" well arainea and freed from molasses as tnat ot the Antilles. The 720 pounds of this substance are then put into a boiler with 270 pounds of water, and the mixture is boiled briskly for n/minutes when 180 additional pounds of water are added, and the boiling is continued for 48 mtnules mor^ An alkaline solution is prepared from the ashes of the plantain tree, strewed over Zw placed in the bottom of an earthen pot perforated with holes. Ninety Sds of J^7r are passed through; and 6 pounds of the clear lixivium are added to th^l^ninJ 7w^ whereby a thick scum is raised which is removed. After 24 minuTe , fou? and a ha J' pounds of a kalme solution and about two fifths of a pound of raw mUk, a?e added • after which the boilmg and skimming are continued 24 minutes. This Tust be repeated IZ/ th ' 1- '''^"' T't ^"'" r ^""'^ ^^""^ ^^^'^''- 240 pounds of water be ng now added, the hquor is to be poured into a number of strainers. These are ba^^ of rn«rc! cotton cloth, in the form of inverted quadrangular pyramids, each of whkMs suspend^ from a frame of wood, about two feet square. The operation of straining occupres^Ib^m 96 minutes The strained liquor is divided into three parts : one of theselput ini^ a boiler, with from half a pound to a pound and a half of alkaline solution!one twelfth of a pound of milk, and 12 pounds of water. After having boiled for between 48 and 72 minutes, three quarters of a pound of milk are added, and the liquor rrourefin equ^ portions, into four refining pots. These are wide at the mouth, and pointed a heff torn ; but are not conical, for the sides are curved. The bottim is nerforat^ anH thZ' stem of a plantain leaf forms a plug for closing theaperture. The^J^^remSni^^'p'rU^^^^^ of the strained hquor are managed in exactly the same manner; so that eich reS pot has its share of each portion. When they have cooled a ittle, the refinin"To! IS removed to the curing-house, and placed on the ground for 24 hours; next=' C t'l ^'' P.w ^ "^^ ^ ^''T' ''}'''^ ^"PP«^^ ^^'"^ ^t '^^^ distance from the^ound A Tht''^^'^"^, ""T"} '' Pl«^^.^"d^r each, to receive the viscid liquor that E from them In order to draw off this more completely, moist leaves of the ValisneHaTvira^ are placed over the mouth of the pot, to the thickness of two inches -X? 10 or 12 days, these are removed ; when a crust of sugar, about half an inch in thickness is found on the surface of the boiled liquor. The crust being broken and removeTfresV lea^^^^^ are repeatedly added, until the whole sugar has formed; which requires from 75 to^ ^Tboile^. ' '"''"'' ^' "''^' '' ^"'' "°^ '^'^^ ^ ^' strained'before it £ putlnto rpl'lic^ aWye-described operose and preposterous process, it is needless to make any remarks. While it is adhered to with the tenacity of Hindoo habit, the West Ind^a has no reason to fear the competition of the East, in the manufacture of sugar, provwS lo sippTy.' th^^selves of the aids which chemical and mechanical sdel^'a^eT^^ In every part of the Behar and Putna districts, several of the confeetionprs nro«.«i. the coarse article called shukkur, which is entirely^imUa? in ap^aranc^^^^^^ LTeriJJ Jamaica sugars. They prepare it by putting some of the thii extract of suVar.™ into coarse sackcloth bags, and by laying weigSts on them, tLy squeezrout th^^ a process perfectly analogous to that contemplated in several English pat- ents, ' , The sugar-mill at Chica Ballapur* IS worked by a single pair of buffaloes or oxen, fig. 1392, going round with the lever a, which is fixed on the top •f the right-hand roller. The two rollers have endless screw heads b, which are formed of 4 spiral grooves and 4 spiral ridges, cut in opposite directions, which turn into one an- other, when the mill is working. These rollers and their heads are of one piece, made of the toughest and ts will not impart any bad taste to the iuice ThtTJJ^ ^^^l ?° ^^ K'-' f "'^ '"^^ wooden frame and their r1i<=f«n«r^r ^ I' f"®^ ^'^^ supported m a thick strong wooden trame, and the r dis ance from each other is regulated by means of wedffef Vhich pass through mortises m the frame planks, and a |roove mad?fn a bit oTS 1393 sort of hard wood, and press upon the axis of one of the rollers. The axis of the other presses against the left-hand side of the hole in the frame-boards. The cane juice runs down the rollers, and through a hole in the lower frame-board, into a wooden conductor, which carries it into an earthen ix»t. Two long-pointed stakes or piles are driven into the earth, to keep the mill steady, which is all the fixing it requires. The tinder part of the lowermost plank of the frame rests upon the surface of the ground, which is chosen level and very firm, that the piles may hold the faster. A hole is dug in the earth, im • mediately below the spout of the conductor, to receive the pot. The mill used in Burdwan and near Calcutta, is simply two small wooden cylinders, grooved, placed horizontally, close to each other, and turned by two men, one at each end. This simple engine is said completely, but slowly, to express the juice. It is very cheap, the prime cost not beinar two rupees ; and being easily moved from field to field, it saves much labor in the carriage of the cane. Notwithstanding this advantage, so rude a machine must leave a large proportion of the richest juice in the cane-trash. It is curious to find in the ancient arts of Hindostan exact prototypes of the sugar-roll- ers, horizontal and upright, of relatively modern invention in the New World. The sugar-mill of Chinapatam, fig. 1393, consists of a mortar, lever, pestle, and regu- lator. The mortar is a tree about 10 feet in length, and 14 inches in diameter : a is a plan of its upper end ; 6 is an outside view ; and c is a vertical section. It is sunk perpendicu- larly into the earth, leav- ing one end 2 feet above the surface. The hol- low is conical, tnncated downwards, and then becomes cylindrical, with a hemispherical projection in its bottom, to allow the juice to run freely to the small open- ing that conveys it to a spout, from which it falls into an earthen pot. Round the upper mouth of the cone is a circular cavity, which collects any of the juice that may run over from the upper ends of the pie- ces of cane; and thence a canal conveys this juice, down the outside of the mortar, to the spout. The beam d, is about 16 feet in length, and 6 inches in thickness, being cut out from a large tree that is divided by a fork into two arms. In the fork an excavation is made for the mortar 6, round which the beam turns horizontally. The surface of this excavation is secured by a semi-circle of strong wood. The end towards the fork is quite open, for changing the beam without trouble. On the undivided end of the beam sits the bullock-driver c, whose cattle are yoked by a rope which comes from the end of the beam ; and they are prevented from dragging out of the circle by another rope, which passes from the yoke to the forked end of the beam. On the arms /, a basket is placed, to hold the cuttings of cane; and between this and the mortar sits the man who feeds the mill. Just as the pestle comes round, he places the pieces of cane sloping down into the cavity of the mortar ; and after the pestle has passed, he removes those that have beea squeezed. or THE MANUFACTURE OF SUGAR IN THE WEST INDIES. Cane-juice varies exceedingly in Hchness, with the nature of the soil, the culture the season, and variety of the plant. It is an opaque fluid, of a dull gray, olive, or olive- green color ; in taste, balmy and saccharine ; exhaling the balsamic odor of the cane ; slightly viscid; and of a specific gravity varying from 1-033 to M06, according to cir- cumstances. When fresh, it consists of two parts; the one liquid, the other solid; the latter of which being merely suspended in the former, and, therefore, separable in a great measure by filtration or repose. The solid matter consists of fragments of the cellular parenchyma of the cane, its fibres, and bark, mechanically protruded through the mill; mixed with a very abundant greenish substance, like that called chlaroj^yle by che- mists. When left to itself in the colonial climates, the juice runs rapidly into the acetous fermentation; twenty minutes being, in many cases, sufllcient to bring on this destruc- bve change. Hence arises the necessity of subjecting it immediately to clarifying pro- 766 SUGAR. SUGAR. 767 eesses, speedy in their action. When deprived of its green fecula and glutinous extrac- tive, It IS still subject to fermentation J but this is now of the vinous kind. The juice flows from the mill through a wooden gutter lined with lead, and being conducted into the sugar-house, is received m a set of large pans or caldrons, called clarifiers. On es- tales which make on an average, during crop time, from 15 to 20 hogsheads of sugar a week, three clanfiers, of from 300 to 400 gallons' capacity each, are sufficient. With pans of his dimension, the liquor may be drawn off at once by a stop-cock or syphon, without disturbing the feculencies after they subside. Each clarifier is hung over a separate fire, the tiue being furnished with a damper for checking th« combustion, or cxiinguishine it altogether. The clarifiers are sometimes placed at one end, and sometimes in the middle ot the house, particularly if it possesses a double set of evaporating pans. Whenever the stream from the mill cistern has filled the clarifier with fresh juice the fire is lighted, and the temper, or dose of slaked lime, diffused uniformly through a little juice, IS added. If an albuminous emulsion be used to promote the clarifyin«', very little lime will be required; for recent cane-lujuor contains no appreciable portion of acid to be saturated. In fact, the lime and alkalis in general, when used in small quantity, seem U» coagulate the glutinous extractive matter of ihe juice, and thus tend to bric'hten it up But il an excess of temper be used, the gluten is taken up again by the strong affinity which is known to exist between sugar and lime. Excess of lime may always be cor- rected by a little alum-water. Where canes grow on a calcareous marly soil, in a favor- able season, the saccharine matter gets so thoroughly elaborated, and the glutinous mu- cilage so completely condensed, that a clear juice and a fine sugar may be obtained Without the use of lime. « *cu 1 A^ r^^ l''^""" ^^?.\^ ^^^ ^^ ^^^ clarifier, a scum is thrown up, consisting of the coagu- lated feculencies of the cane-juice. The fire is now gradually urged till the temperature approaches the boiling point ; to which, however, it must not be suffered to rise. It is tnown to be sufficiently heated, when the scum rises in blisters, which break into white a-oth; an appearance observable in about forty minutes after kindlin*' the fire The damper being shut down, the fire dies out ; and after an hour's repose, the clarified liquor is ready to be drawn off into the last and largest in the series of evaporating pans. In the British colonies, these are merely numbered 1, 2, 3, 4, 5, beginning at the smallest, which hangs right over the fire, and is called the teache ; because in it the trial of the Sirup by touch, is made. The flame and smoke proceed in a straight line along a flue to the chimney-stalk at the other end of the furnace. The area of this flue proceeds, with a slight ascent from the fire to the aperture at the bottom of the chimney; so that be- iween the surface of the grate and the bottom of the teache, there is a distance of 28 inches ; while between the bottom of the flue and that of the grand, No. 5, at the other end of the range, there are barely 18 inches. In some sugar-houses there is planted, in the angular space between each boiler, a basin, one foot wide and a few inches deep, for the purpose of receiving the scum which thence flows off into the grand copper, along a gutter scooped out on the margin of the brick-work. The skimmings of the grand are thrown into a separate pan, placed at its side. A large cylindrical cooler, about six feet wide and two feet deep, has been nlaced in certain sugar-works near the teache, for receiving successive charges of its insnissated sirup Each finished charge is called a skipping,^ because it is skfpp^ or laded out The term striking is also applied to the act of emptying the teache. When upon one skiiv ping of sirup in a state of incipient granulation in the cooler, a second skipping is poorl ed, this second congeries of saccharine particles agglomerates round the first as nuclei o{ crystallization, and produces a larger grain ; a result improved by each successive skip- pmg. This principle has been long known to the chemist, but does not seem to ha^ been always properly considered or appreciated by the sugar-planter n Jn^'T/^^ above described cooler the sirup is transferred into woiden chests or boxes, open at top, and of a rectangular shape ; also called coolers, but which are more proneS crystalhzersorgranulators. These are commonly six in number; each Wng aCt o„e Sr «. t?ff "^'"Z''' ^" r^' ^"'^ f ^' "' ''" ^''' ''''^'- When filled such a mals is coll^u ed, as to favor slow cooling, and consequent large-grained crystall zation. If these boxM be too shallow, the grain is exceedingly injured, as may be easily shown by pouring m^ ^ft san^ '''"^ "'' * '""'" '"^^ ' ^^'"' "" '^""^^"^' '^^' ^^?*'^"^ appear mce a m^d^ in yJ'^"'t"*' • ^^-^^if ^^l "^^.'L^ ^"^"^ J"^?^ «^ the due concentration of the simp in the teache IS difficult to describe, and depends almost entirely on the sacacitv and S'rthfhl'^W nfVh'^^'^S- "^n,^' l'^"^ J"^-^^ "^y ^^« appeaLce of tKdpient grain on the back of the cooling ladle ; but most decide by «/!« /ottcA," that is the fee' and appearance of a drop of the sirup pressed and then drawn into a thread bet we« the thumb and fore-finger. The thread eventually break*, at a certain Hmit of ext^n ion, shrinking from the thumb to the suspended LserXlnX^^^^^^ tional to the inspissation of the sirup. But the appearance of granulation in the thread must also be considered ; for a viscid and damaged sirup may give a long enough thread, and yet yield almost no crystalline grains when cooled. Tenacity and granular aspect must, therefore, be both taken into the account, and will continue to constitute the prac- tical guides to the negro boiler, till a less barbarous mode of concentrating cane-juice be substituted for the present naked teache, or sugar frying-pan. That weak sugars are such as contain an inferior proportion of carbon in their com- position, was first deduced by me from my experiments on the ultimate analysis of vege- table and animal bodies ; an account of which was published in the Philosophical Trans- actions of the Royal Society for 1822. Since then. Dr. Prout has arrived at results confirmatory of my views. See Philosophical Transactions for 1827. Thus, he found pure suifar-candy, and the best refined sugar, to contain 42-85 parts of carbon per cent ; East India susar-candy, 41*9 parts; East India raw sugar in a thoroughly dry state, but of a low quality, 40-88 ; manna sugar, well refined, 28-7 ; sugar from Karbonne honey, 36*36 ; sugar from starch, 36*2. Hence, by caramelizing the sirup in the teache, not only is the crystallizable sugar blackened, but its faculty of crystallizing impaired, and the granular portion rendered weaker. A viscous sirup containing much gluten and sugar, altered by lime, requires a higher temperature to enable it to granulate than a pure saccharine simp ; and therefore the thermometer, though a useful adjuvant, can by no means be regarded as a sure guide, in determining the proper instant for striking the teache. The colonial curing-house is a capacious building, of which the earthen floor is exca- vated to form the molasses reservoir. This is lined with sheet lead, boards, tarras, or other retentive cement ; its bottom slopes a little, and it is partially covered by an open massive frame of joist-work, on which the potting casks are set upright. These arc merely empty sugar hogsheads, without headings, having 8 or 10 holes bored in their bottoms, through each of which the stalk of a plantain leaf is stuck, so as to protrude downwards 6 or 8 inches below the level of the joists, and to rise above the top of the cask. The act of transferring the crude concrete sugar from the crystallizers into these hogsheads is called potting. The bottom holes, and the spongy stalks stuck in them, allow the molasses to drain slowly downwards into the sunk cistern. In the common mode of procedure, sugar of average quality is kept from 3 to 4 weeks in the curing- house; that which is, soft-grained and glutinous must remain 5 or 6 weeks. The curing- house should be close and warm, to favor the liquefaction and drainage of the viscid caramel. Out of 120 millions of pounds of raw sugar, which used to be annually shipped by the St, Domingo planters, only 96 millions were landed in France, according to the authority of Dutrone, constituting a loss by drainage in the ships of 20 per cent. The average transport waste at present in the sugars of the British colonies cannot be estimated at less than 12 per cent., or altogether upwards of 27,000 tons ! What a tremendous sacri- fice of property ! Within these few years a very considerable quantity of sugar has been imported into Great Britain in the state of concentrated cane-juice, containing nearly half its weight of granular sugar, along with more or less molasses, according to the care taken in the boiling operations. I was at first apprehensive that the sirup might undergo some change on the voyage ; but among more than a hundred samples which I have analyzed for the custom-house, I have not perceived any traces of fermentation. Since sugar softens in its grain at each successive solution, whatever portion of the crop may be destined for the refiner, should upon no account be granulated in the colonies ; but should be transported in the state of a rich cane-sirup to Europe, transferred at once into the blowing-up cistern, subjected there to the reaction of bone black, and passed through bag-filters, or through layers of the coarsely ground black, previously to its final concen- tration in the vacuum pan. Were this means generally adopted, I am convinced that 30 per cent, would be added to the amount of home-made sugar loaves corresponding to a given quantity of average cane-juice ; while 30 per cent, would be taken from the amount of molasses. The saccharine matter now lost by drainage from the hogsheads in the ships, amounting to from 10 to 15 per cent., would also be saved. The produce of the cane would, on this plan, require less labor in the colonies, and might be exported 5 or 6 weeks earlier than at present, because the period of drainage in the curing-house -would be spared. It does not appear that our sugar colonists have availed themselves of the proper chemical method of counteracting that incipient fermentation of the cane-juice, which sometimes supervenes, and proves so injurious to their products. It is known that grape- must, feebly impregnated with sulphurous acid, by running it slowly into a cask in which a few sulphur matches have been burned, will keep without alteration for a year; and if must, so muted, is boiled into a sirup within a week or ten days, it retains no sulphureous odor. A very slight muting would suffice for the most fermenta?>le cane- I IH 768 SUGAR. II ;|uice; and it could be easily given, by burning a sulphur match within the cistern immediately before charging it from the mill. The cane juice should, in this case, be heated m the clarifier, so as to expel the sulphurous acid, before adding the temper lime* for otherwise a little calcareous sulphite might be introduced into the suo-ar Thus the acescence so prejudicial to the saccharine granulation would be certainly prevented. Sirup intended for formmg c.ayea sugar must be somewhat more concentrated in the .cache, and run off into a copper cooler, capable of receiving three or four successive skippings. Here it is stirred to ensure uniformity of product, and is then transferred bt ladles into conical moulds, or formes, made of coarse pottery, having a small orifice at the apex, which is stopped with a plug of wood wrapped in a leaf of maize. Thesfl pots are arranged with the base upwards. As their capacity, when largest is sreatlf less than that of the smallest potting-casks, and as the process lasts severalweeks the claying-house requires to have very considerable dimensions. Whenever the sirup is properly granulated, which happens usually in about 18 or 20 hours, the plugs are removed from the apices of the cones, and each is set on an earthen pot to receive the drainings. At the end of 24 hours, the cones are transferred over empty pots, and the molasses contained in the former ones is either sent to the fermenting-house or sold. The claying now begins, which consists in applying to the smoothed surface of the sugar at the base of the cone, a plaster of argillaceous earth, or tolerably tenacious loam in a pasty state. The water diffused among the clay escapes from it by slow infiltra- tion, and descending with like slowness through the body of the sugar, carries along with it the residuary viscid sirup which is more readily soluble than the granulated particles. Whenever the first magma of clay has become dry, it is replaced by a second • and this occasionally in its turn by a third, whereby the sugar cone gets tolerably white and clean. It is then dried in a stove, cut transversely into frusta, crushed into a coarse powder, on wooden trays, and shipped off for Europe. Clayed sugars are sorted into different shades of color, according to the part of the cone from which they were cut • under the denomination in French commerce or premier, second, iroisieme, petit, commun and tete ; the last or the tip being an indifferent article. The clayed sugar of Cuba is called Havana sugar, from the name of the shipping port. Clajed sugar can be made only from the ripest cane-juice, for that which contains much gluten would be apt to get too much burned by the ordinary process of boiling to bear the claying operation. The sirups that run off from the second, third, and fourth applications of the clay-paste, are concentrated afresh in a small building apart, called the refinery, and yield tolerable sugars. Their draininsjs go to the molasses cistern. The cones remain for 20 days in the claying-house, before the sugar is taken out of them. ^ Claying is seldom had recourse to in the British plantations, on account of the increase of labor, and diminution of weight in the produce, for which the improvement in quahty yields no adequate compensation. Such, however, was the esteem in which Ihe French consumers held clayed sugar, that it was prepared in 400 plantations of St. Domingo alone. *^ SUGAR REFINING. Raw, or muscovado sugar, as imported from the colonies, is contaminated more or less with gluten, lune, but particularly caramel, which give its grains a yellow brown tint, an empyreumatic odor, and a soft clammy feel in the hand. If such sugar be dis- solved in water, and the sirup be evaporated by a gentle heat, it wiU afford a sugar of still inferior quality and appearance. This rapid deterioration is in some measure owing to the injurious operation of a prolonged ^^eat upon the crystalline structure, but ^lefly to the chemical reaction of the glutinous ferment and lime upon the sugar. The first care of the refiner should therefore be the immediate abstraction of these noxious alteratives, which he effects by the process called meltings; that is, mixing up the sugar m a pan with hot water or steam into a pap, and transferring this pap into large sugar-moulds. Whenever these become cool, their points are unplugged, and they are set tc Irain for a few days in a warm apartment. Sugar thus cleansed is well pre- pared tor the next refining process ; which consists in putting it into a large square copper cistern along with some lime-water, (a little bullock's blood,) and from 5 to 20 per cent, of bone black, and blowing it up with steam ; or, in other words, injecting steam through the mixture from numerous orifices in copper pipes laid along the bottom and sides of the vessel. Under the influence of the heat and agitation thus occasioned, the saccharine matter is perfectly dissolved and incorporated with the albumen of the blood and the bone black. Instead of the blood, many refiners employ a mixture of gelatinous alumina and gypsum, caUed^ntng*, prepared by adding a solution of alum to a body of lime-water, coUecting, washing, and draimng the precipitate upon a filter. SUGAR. 769 1894 Other refiners nse both the blood and finings with advantage iJone DlacK is now very frequently employed by the sugar-renner, not in a fine meal, but in a granular state, like corned gunpowder, for the purpose of decoloring his sirups ; in which case, he places it in a box, in a stratum 8 or 10 inches thick, and makes the sirup percolate downwards through it, into a cistern placed be. neath. By this means it is deprived of color, and forms th« clairce of the French refiner. When the blowing up cistern ii charged with sugar, finely ground bone black, and blood, the mix. ture must be passed through a proper system of filters. Thai now most in use is the creased bag filter, represented in fies. 1394 1395, 1396. "^ * The apparatus consists of an upright square wooden case o, a, about 6 or 8 feet high, furnished with a door of admission to arrange the interior objects ; beneath is a cistern with an educting-pipe for receiving and carrjing off the filtered liquor; and above the case is another cistern e, which, like the rest, is lined with tinned sheet copper. Into the upper cistern, the sirup mixed with animal charcoal is introduced, and passes thence into the mouths «, e, of the several filters d, d. These consist each of a bag of thick tweeled cotton cloth, about 12 or 15 inches in diameter, and 6 or 8 feet long, which is inserted into a narrow bottomless bag of canvass, about 5 inches in diameter, for the purpose of folding the filter-bag up into a small space, and thus enabling a great extent of filtering surfaces to be compressed into one box. The orifice of each compound bag is tied round a conical brass mouth-piece or nozzle e, which screws tight into a corresponding opening in the copper bottom of the upper cistern. From 40 to 60 bags are mounted in each filter case. The liquor which first passes is generally tinged a httle with the bone black, and must be pumped back into the upper cistern, for refil- tration. In cold weather the interior of the case may be kept warm by a proper dis- tribution of steam-pipes. Fig. 1395 shows one mode of forming the funnel-shaped nozzles of the bags, in which they are fixed by a bayonet catch. Fig. 1396 shows the same made fast by means of a screwed cap, which is more secure. The next process in sugar-refining is the evaporation of the clarified sirup to the granulating or crystallizing pitch. The more rapidly this is effected, and with the less scorching injury from fire, the better and greater is the product in sugar-loaves. No apparatus answers the refiner's double purpose of safety and expedition so well as the •cuum-pan of Howard. F^. 189Y shows the structure of a single vacuum-pan. The horizontal diameter of the copper spheroid a is not less than 5 feet; the depth of the under hemisphere is at Ijeast 18 mch€« from the level of the plane; and the height of the dome-cover is 2 feet Ihe two hemispheres (of which the inferior one is double, or has a steam-jacket) ars f.'in^'f ?f ^^ ^?'^! *"*^ f""^^^^ "^''^^ P^«^'"g b^t^«^« ^^^ fla"g«« to preserve ths joints tight against atmospheric pressure. The jacket of the lower hemisphere forms the case of the steam, which communicates heat to the syrup enclosed in the innef hemisphere. In general, the pans contain, when filled to the flange, 100 gallons of syrup, and yield about 11 cwt of granulated sugar at every charge ^ r.\t "P'"*'^'?^, the vacuum spheriod ; b, the neck with the lid. From the side of b, a ve?ticTr>TJ K connirr TT^^ ^^ ^" ^?"' .P^P^ ^' ^' ^»»i«^ terminates in V, vertical pipe k, connected with the vacuum main-pipe k, proceeding horizontally from ^is'l^o^d ? ^""'/mT- ^^ '^' ^^^''^ ^' '^' toVof ^^a valve, movablT by a sc^ Lhi?i . i .1''^^^^"'''°^.^' '"^'>^ ^^ ^^^ connection with the air-pump at pleasSI fhfZi • T. '^^ ™'*'"'.^ S?,^^'°' ^'•«'" ^^''^^ ^^^ successive charges are a^dmitted into D^ne^und.r?h' "'f'"'' \^l'^ ^^'^ ^^' '^'^' '^'''^' ^^^ opening the stopcock "on aJ pipe under the ceiling, which communicates with the filter-cistern placed above ois ThiJnw'r P^"^'.^k'' *' '^' ^/''"™ ^^ '^' P^°' ^^^^ discharging the^granulatfng syru^ It 1^1 lL??rnrlvi^ T • \"^ " P"^/'^"^ '"^r \^**^»»^^ "^^^ '''^^ connection litlth^ theS ^I/ZouT^ intercepted, i, is the barometer, or manometer, for showing reeeiv?n^ /nv llJl? corresponding to the temnerature. n, k, is a cistern-pipe for Ze ill off h^l^nJT .""-^ K T^ ^r'^^^^^^y boil over the neck b. Its ^ntenU Zj^\ri.^ • '^°P9°^^^^ »t8 bottom from time to time, m shows the place of the £r! -^See t/ra °^''''''"' '"^ ^''" ^^^^ ^"^ * «""P^^ ^^ ^^^^P ^^t^^^"* ^^"^^^S »A^ff^A^T^V''^Z ?'*°**'"l ^^^"^ 2? ^*"«°«- This quantity of syrup being first S?,r.i !J' • • T-^^^ ^ \''r^^^" P'^^^ *^^ concentratioS. a second measure is in™ duced, the inspissation of which is supposed by some refinera to cause an agglomeration T70 SUGAK. 1397 I I of sacchanne matter round the first crystalline particles. The repetition of tnis proeeM for two or three times is imagined to produce the large brilliant grain of vacuum-pan sugar. This hypothesis is more specious than sound, because the granulating syrup discharged from the pan is subjected to a heat of 180° or 190° in the subjacent steam- cased receiver, whereby the granulations are again reduced to a very small size. Into this receiver, two or three skippings or discharges of the pan are admitted in succesaion, and the whole are diligently mixed and agitated by a stirring oar. It is by this proceae that the granulating tendency is promoted and determined. From this receiver (absurdly enough called a cooler) the moulds are filled in the usual way, by means of copper basins or large ladles. The case of the under hemisphere of the vacuum-pan is filled with steam, generated under a pressure of 4 or 6 pounds on the square inch ; the heat of which causes the interior syrup to boil rapidly while the air-pump is kept in action. A small escape-pipe for -waste steam must be placed at the opposite side of the case or jacket, to ensure its equal distribution ; as also a stopcock below, to let oflf the water of condensation. The paos «re mounted on iron feet, or short pillars, which insulate them from the floor, and allow their whole surface to be inspected, and any flaw to be repaired. The air-pump usually stands in a cold-water cistern, to favor the condensation of the aqueous vapor, which It draws out of the pans; and it is kept in constant action by the steam-engine, being attached to the working-beam of its piston. Mg. 1398 exhibits the general arrangement of the vacuum-pans, and their subsidiary apparatus. Here are shown, on the ground floor, the heaters e, e (miscalled coolers), into which the concentrated syrup is let down. These heaters are made of copper, in one piece, surrounded with a cast-iron jackets bolted at the flange or brim to it Each pan contains, when full, about 350 gallons, equivalent to nearly 86 cwt. of crystallized sugar. They are furnished with steam-cocks and waste steam-pipes. Under the level of the spheroiA d,d, the horizontal main pipe is seen, for supplying the cases with steam. In the face of each pan, above the line b, b, the handle of the proof-stick appears, like that of a stop- cock. The distribution of the measure cisterns, and some other parts of the pans^ w slightly varied in this representation from the former. From the bottom of the liquor cisterns c, c, pipes descend to the charging measures a, a, below. The cisterns c, c, are made of copper, and contain each about 400 gallons. Six tons of refined sugar can be turned out daily in a three-pan house. Fig. 1399 represents in section another form of the vacuum-pan. a is the spheroidal eopper vessel, supported by four iron columns 6, 6. It may be discharged by meant of Ike pipe c, which is secured with a conical valve d. This may be opened or shot, bf acting on the lever e. The lower of the two hemispheres of which the pan is composed IS double, and the interstitial space/,/, is filled with steam by the pipe g, as the heetduT and evaporating agent, h, is the steam valve ; i, the pipe for the efflux of the condensed water, /c, a tube for the escape of the air at the commencement of the operation. L is an apparatus inserted air-tight into the cover of the vacuum-pan, and which dips down into the sirup; serving to take out a sample of it, without allowmg air to enter, and 1 Jm^ 1*"?^ lino P/i!?^^fn; ?\^ construction of this instrument is exhibited in Jigs. ll:Ik '^' ^' ^^A^- ^^^?' '^^'''^ "^'^ ^^ presently explained, tn, is the thermometer, ^ut v.±? ^^uT^ ■lltV^t.^"'^^! '. ^^^^"^ ^^' »^ ^»»« barometer. «, is the charger o^ gauge-vessel, fi»ed with the filtered sirup, which it discharges by the pipe «'. o, is the cover or capital of the vacuum-pan. o', is a safety-valve, through which the air may be admitted ail er the completion of the process, p, is a bent pipe, slanting downwirds with a stopcock 9 at its end, to receive the superfluous sirup. The vapor, which is disengaged from the sirup during its concentration, is extracted from the top of the pan into the pipe r, passes from this into the vessel *, which is divided by a plate of T72 SUGAR. SUGAR. 773 copper into two compartments. The syrap forced over aecidentallj in the ebullition, goes into the vessel », and passes by the glass tube t, into the pipe p. The glass tube serves to show the quantity of the sirup that has boiled over, so that it may be drawn off when necessary. For this purpose, the stopcock «, of the vessel v, must be closed, and q must be opened, in order to fill r, while the air contained in it escapes into the pan. The stopcock q, being then shut, and u, with the little air-cock a:, opened, the sirup will flow into the large receiver placed beneath it, commonly but erroneously called a cooler; because it is a double copper basin, with steam in the interstitial space. The hot steam rushes from a, into the cast-iron vessel y, where it is condensed. «, is a pipe for introducing the water of condensation through the copper rose a\ The condensed water flows through the pipe b', and the valve e', to the air-pump, which receives motion from the shaA of the steam-engine. The vacuum-pan was originally heated solely by the admission of steam between the 1400 double bottom ; but of late years the heat has been also applied to the simp through several coils of pipe placed within the pan, filled with steam at a temperature many degrees above 212° F., sometimes so high as 250°. By this double application of heat, the evaporating power of a pan has been vastly increased. The latest made pans have a considerably flat bottom, fig, 1400 ; a spiral pipe, laid close upon it ; and between the under hemisphere and the upper one, there is a space a, a, 2^ feet high, to give the sirup room for frothing up without boiling over. The space b, of the bottom receives steam of common pressure, and the spiral tubes, of high pressure. A pan like this is now making for a house in London, which is to work off 16 tons of sugar-loaves daily. The proof-stick, ^g. 1405, consists of a cylindrical rod, capable of being screwed air- tight into the pan in an oblique direction downwards. The upper or exterior end is open ; the under, which dips into the sirup, is closed, and has on one side a slit a (figs. 1401, 1402) cr notch, about | inch wide. In this external tube, there is another shorter tube 6, capable 1402 1401 m of moving round in it, through an arc of 180°. An opening upon the under end «, corre- sponds with the slit in the outer tube, so that both may be made to coincide, fig. 1401, A. A wooden plug d, is put in the interior tube, but so as not to shut it entirely. Upon the upper end there is a projection or pin, which catches in a slit of the inner tube, by which this may be turned round at pleasure. In the lower end of the plug there is a hole e, which can be placed in communication with the lateral openings in both tubes. Hence it if possible, when the plug and the inner tube are brought into the proper position, a, fig, 1401, to fill the cavity of the wooden rod with the sirup, and to take it out without allowing any air to enter. In order to facilitate the turning of the inner tube within the outer, there is a groove in the under part, into which a little grease may be introduced. Whenever a proof has been taken, the wooden plug must be placed in reference to the mner tube, as shown in fig. 1401, c, and then be turned into the position a ; when the cavity of the plug will again be filled with sirup, c must be now turned back to the for- mer position, whereby all intercourse with the vacuum-pan is cut off; the plug being drawn «fut a little, and placed out of communication with the inner tube. The plug is then turned into the position b, drawn out, and the proof examined by the fingers. Table showing the boiling point of sirup, at the corresponding atmospheric pressure within the vacuum-pan : — Height of the mercury (iachei) in oae leg of the syphon, abore that in the other— 0-74 0»86 1-01 M7 1-36 1-57 1-80 205 2-36 2-72 3- 10 3-52 4-OU. *^ a 1407 Boiling point, Fahr.— 116° 120^ 126° 130° 135° 140° 145° 150° 165° 160° 165° 170° HS®. The large double steam-basin, which receives several successive skippings of the concentrated granulating sirup, serves to heat it from the temperature of 160® or 170°, at which it leaves the vacuum-pan, up to 200° or thereby, before it is filled out into the moulds ; for were it introduced in the cooler state, it would not concrete into sufliciently compact loaves. The following apparatus is used in many French sugar-houses, for concentrating sirups, called the sioing pan, or chavdilre H bascule. It is represented in fig, 1406, in 1406 elevation, and in^g. 1407, in ground plan, a, is the pan; bj its spout ; c, the axis or pivot round which it swings, so as to empty itself, when raised behind by the chain d ; e, is the furnace door ; /, the passage to the fireplace and grate g ; A, A, A, side flues for conducting the smoke into the chimney. The duly clarified, concentrated, granulated, and re- heated sirup, is transferred, by means of copper basins, from the coolers into conical moulds, made either of brown and somewhat porous earthenware, or of sheet iron, strongly painted. The sizes of the moulds vary, from a capacity of 10 pound loaves, to that of 56 pound bastards — a kind of soft brown sugar obtained by tbe concentration of the inferior sirups. These moulds have the orifices at their tips closed with bits of twisted paper, and arc set up in rows close to each other, in an airy apartment adjoining the coolers. Here they are left several hours, commonly the whole night, after being filled, till their contents become solid, and they are lifted next morning into an upper floor, kept at a temperature of about 80° by means of ^♦•'am pipes, and placed each over a pot to receive the sirup draining^ — the paper plug being first removed, and a steel wire, called a piercer, being thrust up to clear away any concretion firom the tip. Instead of setting the lower portion of the inverted cones in pots, some refiners arrange them in wooden racks, with their apiees suspended over longitudinal gutters of lead or zinc, laM with a slight slope upon the floor, and terminating in a sunk cistern. The sirup which flows off spon- taneously is called green sirup. It is kept separate. In the course of two or three days, when the drainage is nearly complete, some finely clarified sirup, made from loaf sugar, called liqtior by the refiners, is poured to the depth of about an inch upon the base of each cone, the surface having been previously rendered level and solid by an iron tool, called a bottoming trowel. The liquor, in percolating downwards, being already a saturated sirup, can dissolve none of the crystalline sugar, but only the colored molassy matter ; whereby, at each successive liquoring, the loaf becomes whiter, from the base to the apex. A few moulds, taken promiscuously, are emptied from time to time, to inspect the progress of the blanching operation ; and when the loaves appear to have acquired as much cotor, according to the language of refiners, as is wanted for the particular market, they are removed from the moulds, turned on a lathe at the tips, if necessary, set for a short time upon their bases, to diffuse their moisture equally through them, and then transferred into a stove heated to 130° or 140° by steam pipes, where they •re allowed to remain for two or three days, till they be baked thoroughly dry. They are then taken out of the stove, and put up in blue paper for sale. In the above description of sugar-refining, I have said nothing of the process of clay- ing the loaves, because it is now nearly obsolete, and abandoned in all well-appointed sugar-bouses. Those of my readers who desire to become acquainted with sugar- refining upon the old plan, may consult my Report made upon the subject to the Honorable Housb of Commons in July, 1833; where they will find every step detailed, and the numercial results stated with minute accuracy. The experiments subservient to that oflUcial report were instituted purposely to determine the average yield or pro- duct, in double and single refined loaves, lumps, bastards, and treacle, which different kinds of sugar would afford per cwt, when refined by decoloring with not more than 5 per cent of bone black, boiling in an open pan, and clearing the loaves with clay-pap. Centrifugal action has been of late years had recourse to for separating the uncryst^- lizable from the granular portion of sugar ; and the following mode of applying it seems to be one of the most efficacious. It was patented in October 1849, by Mr. C. W. Finzel, of Bristol. Fia. 1408 is an elevation, partly in section ; fiff. 1409 is a vertical section, and^. 1410 a front view (both on a larger scale than/^. 1408) of the perforated box, by I mm 774 SUGAR. SUGAR. 775 mm Hi 1411 1413 which steam is caused to act against the periphery of the cylinder or drum of the machine. In the outer ease a, a narrow recess b, of nearly the same height as the revolving cylinder c is formed ; and in this recess is placed the steam box d, connected by a pipe e, with a steam boiler. The side of the box d, which is nearest to the cylinder «, is per- forated with small holes, through which the steam rushes in numerous jets against the periphery of the cylinder c ; and such steam is prevented from escaping from the machine by the application of lids/, to the top of the case a. The mode of operating with the machine is as follows: — The sugar having been mixed with molasses or syrup, to bring it to the proper con- sistency, is put in the cylinder c, which is then caused to rotate ; and after the cylinder has made a few turns, the steam is let on (by turning a cock on the pipe c), and per- mitted to issue freely through the holes in the box d, against the periphery of the cylinder for about a minute, which has the effect of clearing the meshea The state of the sugar may be ascertained, from time to time, without stopping the machine, by raising the lids /; and if the extraction of the moisture therefrom appears to be impeded, steam is to be again let on for a short time, in order to clear the meshes. The cylinder c is to be kept rotating, and the steaming repeated occasionally (if required) until the whole or nearly the whole of the syrup or fluid is extracted from the sugar; and this, when operating upon ordinary sugar, will generally be effected in a few minutea Sugars taken from the evaporating pan, after partial cooling, may be put into the machine, and operated upon directly, as above. The apparatus, ^^. 1411, is for working such sugars as require to be previously mixed with liquid. It consists of a vessel with a series of steam-pipes fixed in it ; and of a cen- trifugal sieve and centrifugal drum, both fixed upon the same shaft, which revolves in the vessel, a is the vessel, in the centre of which a vertical shaft 6, is mounted. This shaft for about two thirds of its length from the top is made hollow ; and upon it is fixed a small centrifugal drum c, having a perforated periphery, and furnished with divisions or leaves, projecting inward, to impart to the fluid (which enters it through openings in the shaft 6), the centrifugal speed of the shaft The shaft h also carries a sieve d, the meshes of which are made coarser or finer at pleasure ; and for breaking any accretions of crystals the sieve is furnished with a number of metal points. A receptacle «, is formed at the upper part of the vessel, to receive any lumps that may happen to be thrown over the top of the sieve. Beneath the sieve several perforated steam pipes/, are fixed for the purpose of causing steam to be brought in contact with the particles of sugar which pass through the sieve. Thus: — Communicate motion to the shaft 6, and admit steam to the pipes/, through the pipe/, then introduce the syrup with which the sugar is to be mixed into the drum c, through the shaft h. The sugar which has been prepared by crushing is deposited in the centre of the sieve, whence it is thrown by the centrifugal action through the meshes of the sieve ; it then descends through the steam that issues from the pipes / whereby it is moistened and prepared to receive the syrup, which is thrown from the drum c, and thus become mixed with the sugar. Fig. 1412, is an elevation, partly in section, of a vacuum-pan, with the improved ftp* paratus applied thereto, a, is the vacuum-pan^ the head h, of which is connected by ft copper pipe c^ with a condenser d — shown in vertical section at Jig. 1413. The con- denser consists of a metal cylinder with conical ends, which are separated from the body of the cylinder by plates e ; but a communication is established between the two ends by a series of copper pipes/ which are inserted at top and bottom into the plates «, At the bottom of the cylinaer there is a pipe g, by which cold water is admitted into it ; and at the top there is a pipe A, through which the water flows away. The bottom of the condenser is connected with a receiver i, by a pipe^', provided with a stop- valve, which can be worked by means of the crank-handle *:. The receiver is furnished with steam-pipes t^, for evaporating the water of condensation, as represented in Jig. 1414 — which is a plan-view of the receiver «, with the top removed. The receiver is con- nected by a pipe I, with a second condensing vessel in, which is divided longitudinally, near the top, by a perforated plate n supported by vertial bearers o. There is a per- forated pipe p, at the top of the condenser m, by which cold water is supplied to the upper compartment thereof, whence it descends in a shower through the perforations in the plate ti, and condenses the aqueous vapor in the lower compartment The con- denser m, is connected with the exhausting pumps by the pipe q. The progress of the operation is as follows : — As the vapor from the vacuum-pan Products of refining in Bond. Rejinery A. Foreign sugar received into finery ... Brltiah refined, ditto 28993 1 10 7306 1 27 9644 2 8 re- Cwt. qr. 47,479 3 240 lb. 14 47,719 3 14 45944 1 17 45944 1 17 946 46890 1 17 240 47130 1 17 Delivered for exportation atores, tc. : — Refined sugar • • Bastards - • Treacle Raw sugar removed to other re. finery ... Syrup, ditto . . - Scrapings, ditto Samples ... Total • Deficiency Balance CwL qr. lb. 28,993 1 7,306 1 9,644 2 10 27 8 385 2 284 1 145 14 14 7 10 23 46,773 2 946 15 27 47,719 3 14 Refinery B. Foreign sugar received into re. finery .... British refined (bastard) • 56800)41770 ( 73-5 39760 25 Cwt. qr. lb. 56,485 1 22 314 21 Delivered for exportation stores, tc.:— Refined sugar ... Bastards ... Treacld ... Total Deficiency Balance > Cwt qr. lb. 41,770 26 1,425 3 4 12,194 2 4 66,799 2 15 ■ 55,390 2 6 1,409 9 20100 21-5 17040 100-0 3060 56800)1426 (2-5 1136 56,799 2 15 2900 56800)121950 (21-4 or 5 113600 83500 56800 26700 A»00)140900 (2-5 11360 27300 776 SUGAR. SUGAR. 777 "pMses through the condenser d, a portion of it is condensed in the pipes/ together with the saccharine matters, and flows from the bottom of the condenser into the re» eeiver «, in the state of a weak solution of sugar. Steam being admitted into the pipes t^, the heat thereof (in combination with the action of the exhausting pumps) evaporatet the solution to a more concentrated state; and then it may be drawn off through the pipe r; — air being at the same time admitted into the receiver through a cock at i; to supply the place with liquor as it flows away. If the pumps are kept in action during this part of the process, a throttle yalye must be used to close the pipe /. Refinery C. flareign sugur received 44)54-7 22- 10-7 Cwt. qr. lb. 8,074 3 Delivered for exportation stores, tc. :— Refined sugar • Bastards Treacle Samples Total Deficiency* Balance • CwL qr. lb. 4,396 1 1,775 1 8.V> 3 2 11 15 7 21 7,080 1.043 3 26 5 8,074 3 * Mem. — An accident happened by tlie bursting of a boiler BEET-ROOT SU6AK. The physical characters which serve to show that a beet-root is of good quality, are its being firm, brittle, emitting a creaking noise when cut, and being perfectly sound within; the degree of sweetness is also a good indication. The 45th degree of latitude appears to be the southern limit of the successful growth of beet in reference to the extraction of sugar. Extraction of Sugar from the Beet. — The first manipulations to which the beets are exposed, are intended to clear them from the adhering earth and stones, as well as the fibrous roots and portions of the neck. It is desirable to expose the roots, aAer this operation, to the action of a cylinder washing-machine. The parenchyma of the beet is a spongy mass, whose cells are filled with juice. The cellular tissue itself, which forms usually only a twentieth or twenty-fifth of the whoje weight, consists of ligneous fibre. Compression alone, however powerful, is inadequate 10 force out all the liquor which this tissue contains. To efiect this object, the roots must be subjected to the action of an instrument which will tear and open up the greatest possible number of these cells. Experiments have, indeed, proved, that by the most considerable pressure, not more than 40 or 50 per cent, in juice from the beet can be obtained ; whilst the pulp procured by the action of a grater produces from 75 to 80 percent. 1416 n 1415 The beet-root rasp of Moulfarine is represented in^gx. 1415, 1416- a, a, is the frame- work of the machine ; 6, the feed-plate, made of cast iron, divided by a ridge into two parts ; c, the hollow drum ; d, its shaft, upon either side of whose peripheiy nuts are screwed for securing the saw blades e, e, which are packed tight againrt each other by means of laths of wood ; /, is a pinion upon the shaft of the drum, into which the whed g works, and which is keyed upon the shaft A; t, is the driving rigger ; Ar, piller of sup- port; /, blocks of wood, with which the workman pushes the beet-roots against the re- volving-rasp : m, the chest for receiving the beet-pap ; n, the wooden cover of the dram, lined with sheet iron. The drum should make 500 or 600 turns in a minute. A few years ago, M. Dombasle introduced a process of extracting the juice from the beet without either rasping or hydraulic pressure. The beets were cut into thin slices by a proper rotatory blade machine; these slices were put into a macerating cistern, with about their own bulk of water, at a temperature of 212° F. After half an bourns maceration, the liquor was said to have a density of 2° B., when it was run off into a second similar cistern, upon other beet-roots; from the second it was let into a third, and so on to a fifth ; by which time, its density having risen to 5|°, it was ready for tte {>roce88 of defecation. Juice produced in this way is transparent, and requires littlw ime for its purification ; but it is apt to ferment, or to have its granulating power im- paired by the watery dilution. The process has been accordingly abandoned in most establishments. I have seen the following operations successfully executed in a beet-root factory near Lille, and have since verified their propriety in my own laboratory upon white beets, grown near Mitcham in Surrey. My product was nearly 5 per cent. ; it was very fair, and large grained, like the vacuum-pan sugar of Demerara, but w^ithout its clamminess. The roots were washed by a rotatory movement upon a grating made like an Archime* des' screw, formed round the axis of a squirrel-cage cylinder, which was laid horizontally beneath the surface of water in an oblong trough. It was turned by hand rapidly, witk the intervention of a toothed wheel and pinion. The roots, after being sufficiently agitated in the water, were tossed out by the rotation at the end of the cyliirfer farthest from the winch. They were next hoisted in a basket up through a vr^p-hole into the floor above, by means of a cord and pulley moved by mechanical power; a six-horse steam engine, upon Woolfe's expansive principle, being employed to do all the heavy work. They were here subjected to the mechanical grater (raj?e mecontgttg), &ee^g». 1098, 1099, which had, upon its sloping feed-table, two square holes for receivin? at least two beets at a time, which were pushed forwards by a square block of wood held in the workman's hand by means of a strap. The rasp was a drum, having rows of straight saws placed half an inch apart round its periphery, parallel to the axis, with teeth projecting about I of an inch. The space between each pair of saws was filled with a wedge of wood. The steel slips, or saw plates, were half an inch broad, twelve inches long, and serrated on both their longitudinal edges, so that when the one line of teeth was blunted, the other could be turned out. The drum made 750 turns per minute. The pulp from the rasp fell into a flat trough placed beneath, whence it was shovelled into small bags. Each bag had its mouth folded over, was laid upon a wicker plate, and spread flat with a rolling-pin. The bags and hurdles were then piled in the hydraulic press. There were three presses, of which the two allotted to the first pressure were charged alternately, and the third was reserved for a final and more durable pressure of the marc. See Press, hydraulic, and Stearine Press. The juice flowed over the edges of the wicker plates, and fell into the sill-plate of the press, which was furnished with upright borders, like a tray, through whose front side a pipe issued, that terminated in a leathern hose, for conducting the juice into an elevatea cistern in the boiling-house. Here one pound of slaked lime was mixed with every four hectolitres (about 88 gallons imp.) of juice. The mixture was made to boil for a little while in a round pan alongside, whence it was decanted into oblong flat filters, of blanket stuff". The filtered liquor, which had in general a spec, gravity of 15<* £aume (about double that of the fresh juice), was now briskly concentrated by boiling, in an oblong pan, till it acquired the density of 28° B. The fire being damped with raw coal, the sirup was run off" rapidly by a stopcock into a large basin with a swing handle, and immediately replaced by fresh defecated liquor. The basin was carried by two men to the opposite side of the boiling-house, and emptied into a cistern set on a high platform, whose horizontal discharge-pipe was provided with a series (five) of stopcocks, placed respectively over five copper chests (inverted truncated pyramids), containing a thick bed of granular bone black, covered with a perforated copper plate. The hot sirup thus filtered had a pale straw-color, and was subsequently evaporated in swing pans,^g«. 1406, 1407, over a brisk fire, in quantities equivalent to half a cwt. of sugar, or four hectolitres of average juice. MAPLE SUGAR. The manufacture of sugar from the juice of a species of maple tree, which grows 778 SUGAR. SUGAR. 779 spontaneously in many of the uncultivated parts of North America, appears to hare been first attempted about 1752, by some of the farmers of New England, as a branch Df rural economy. The sugar maple, the Jicer sacc^annttm of LinnsBus, thrives especially in the States of New York and Pennsylvania, and yields a larger proportion of sugar than that which grows upon the Ohio. It is found sometimes in thickets which cover five or six acrei of land; but it is more usually interspersed among other trees. They are supposed to arrive at perfection in forty years. The extraction of maple sugar is a great resource to the inhabitants of districts far removed from the sea; and the process is very simple. After selecting a spot among surrounding maple trees, a shed is erected, called the sugar-camp^ to protect the boilers and the operators from the vicissitudes of the weather. One or more augers, three fourths of an inch in diameter ; small troughs for receiving the sap ; tubes of elder or sumach, 8 or 10 inches long, laid open through two thirds of their length, and corres- ponding in size to the auger-bits; pails for emptying the troughs, and carrying the sap to the camp; boilers capable of holding 15 or 16 gallons; moulds for receiving the sirup inspissated to the proper consistence for concreting into a loaf of sugar ; and) lastly, hatchets to cut and cleave the fuel, are the principal utensils requisite for this manufacture. The whole of February and beginning of March are the sugar season. The trees are bored obliquely from below upwards, at 18 or 20 inches above the ground, with two holes 4 or 5 inches asunder. Care must be taken that the auger penetrates no more than half an inch into the alburnum, or white bark ; as experience has proved that a greater discharge of sap takes place at this depth than at any other. It is also advisa- ble to perforate in the south face of the trunk. The trough, which contains from two to three gallons, and is made commonly dt white pine, is set on the ground at the foot of each tree, to receive the sap which flowi through the two tubes inserted into the holes made with the auger ; it is collected together daily, and carried to the camp, where it is poured into casks, out of which the boilers are supplied. In every case, it ought to be boiled within the course of two or three days from flowing out of the tree, as it is liable to run quickly into fermentation, if the weather become mild. The evaporation is urged by an active fire, with careful skimming during the boiling ; and the pot is continually replenished with more sap, till a large body has at length assumed a sirupy consistence. It is then allowed to cool, and passed through a woollen cloth, to free it from impurities. The sirup is transferred into a boiler t* three fourths of its capacity, and it is urged with a brisk fire, till it acquires the requisite consistence for being poured into the moulds or troughs prepared to receive it. This point is ascertained, as usual, by its exhibiting a granular aspect, when a few drops are drawn out into a thread between the finger and the thumb. If in the course of the last boiling, the liquor froth up considerably, a small bit of butter or fat is thrown into it. After the molasses have been drained from the con- creted loaves, the sugar is not at all deliquescent, like equally brown sugar from the cane. Maple sugar is in ta^^te equally agreeable with cane sugar, and it sweetens as well. When refined, it is equally fair with the loaf sugar of Europe. The period during which the trees discharge their juices is limited to about six weeks. Towards the end of the flow, it is less abundant, less saccharine, and "Eoro difiicult to be crystallized. Sugar op potatoes, grapes, or starch. About eight years ago a sample of sweet mucilaginous liquid was sent to me for analysis, by the Honorable the Commissioners of Customs. It was part of a quantity imported in casks at Hull, from Rotterdam. It was called by the importers, " Vegetable Juice." I found it to be imperfectly sacchari- fiied starch or fecula ; and, on my reporting it as such, it was admitted at a moderate rate of duty. Some months after I received a sample of a similar liquid from the importer at Hull, with a request that I would examine it chemically. He informed me, that an im- portation, just made by him of 30 casks of it, had been detained by orders of the Excise, till the sugar duty of 25«. per cwt of solid matter it contained was paid upon it It was of specific gravity 1*362, and contained SO per cent of ill-saccharified fecula. In the interval between the first importation and the second, an Act of Parliament had been obtained for placing every kind of sugar, from whatever material it was formed, under the provisions of the " Beet-root Sugar Bill." As the saccharometer tables, subservient to the levying of the excise duties, under this Act, were constructed by me, at the request of the President of the Board of Trade, I well know that 50 per cent of the syrup of the beet-root was deducted as a waste product because beet-root molasses is too crude an article for the use of man. Well saccharified starch paste, however, constitutes a syrup, poor indeed in sweetness when compared with cane syrup, or that of the beet-root \ but then it does not spontaneously blacken into molasses, by eyaporation, as solutions of ordinary sugar never fail to do when iJiey are eoneentrated, even with great care. Hence tlje residuary syrups of saccharified fecula may be all worked up into a tolerably white granular mass, which, being crushed, is used by greedy grocers to mix with dark-brown bastard sugars, to improve their color. It ie only within a few years that sugar has been in this country manufactured from potato starch to any extent though it has been long an object of commercial enterprise in France, Belgium, and Holland, where the large coarse potatoes are used for this purpose. The raw material must be very cheap there, as well as the labor ; for potato flour or starch, for conversion into sugar, has been imported from the continent into this country in large quantities, and sold in London at the low price of 10*. per cwt. The process usually followed by the potato-sugar makers, is to mix 100 gallons of boiling water with every 112 lbs. of the fecula, and 2 lbs. of the strongest sulphuric acid. This mixture is boiled about 12 hours in a large vat, made of white deal, having pipes laid along its bottom, which are connected with a high pressure steam-boiler. After being thus saccharified, the acid liquid is neutralized with chalk, filtered, and then evaporated to the density of about 1 -300, at the boiling temperature, or exactly 1*342, when cooled to 60^. When syrup of this density is left in repose for some days, it concretes altogether into crystalline tufts, and forms an apparently dry solid, of spe- cific gravity 1*39. When this is exposed to the heat of 220°, it fuses into a liquid nearly as thin as water; on cooling to 150°, it takes the consistence of honey, and at 100** F. it has that of a viscid varnish. It must be left a considerable time at rest be- fore it recovers its granular state. When heated to 270°, it boils briskly, gives ofi" one tenth of its weight of water, and concretes, on cooling, into a bright yellow, brittle, but very deliquescent mass, like barley sugar. If the syrup be concentrated to a much greater density than 1*340, as to 1*362, or if it be left faintly acidulous, in eithet tase it will not granulate, but will remain either a viscid magma or become a con<*;ete mass, which may indeed be pulverized, though it is so deliquescent as to be unfit for the adulteration of raw sugar. The Hull juice is in this predicament, and is therefore, in my opinion, hardly amenable to the new sugar law, as it can not by any means be worked up into even the semblance of sugar. Good Muscovado sugar, from Jamaica, fuses only when heated to 280°, but it tarns immediately dark brown, from the disengagement of some of its carbon, at that tem- perature, and becomes, in fact, the substances called " caramel" by the French, which is used for coloring brandies, white wines, and liqueurs. Thus we see that starch or grape-sugar is well distinguished from cane-sugar, by its fusibility, at a moderate heat, and its inalterability at a pretty high heat. Its sweet- ening power is only two fifths of that of ordinary sugar. A good criterion of incom- pletely formed starch-sugar is, its resisting the action oi sulphuric acid, while perfectly saccharified starch or cane-sugar is readily decomposed by it. If, to a strong solution of imperfectly saccharified grape-sugar, nearly boiling hot, one drop of strong sulphuric acid be let fall, no perceptible change will ensue, but if the acid be dropped into solu- tions of either of the other two sugars, black carbonaceous particles will make theii appearance. The article which was lately detained by the Excise, for the high duties, at Hull, is not affected by sulphuric acid, like the solutions of cane-sugar, and of the weU-made potato-sugar of London ; and for this reason I gave my opinion in favor of admitting the so-called vegetable juice at a moderate rate of duty. I submitted the solid matter, obtained by evaporating the Hull juice, to nltimate analysis, by peroxide of copper, in a combustion tube, with all the requisite precau- tions, and obtained, in one experiment, 37 per cent, of carbon ; and in another 38 per, cent., when the substance had been dried in an air bath, heated to 275°. The differ- ence to 100, is hydrogen and oxygen, in the proportion to form water. Now this is nearly the constitution of starch. Cane-sugar contains about 5 per cent, more carbon, whereby it readily evolves this black element, by the action of heat or sulphuric acid. An ingenious memoir, by Mr. Trommer, upon the distinguishing criteria of gum, dextrine, grape-sugar, ar.l cane-sugar, has been published in the 39th volume of the " Annalen der Chemie und Pharmacie." I have repeated his experiments, and find them to give correct results, when modified in a certain way. His general plan is to expose the hydrate of copper to the action of solutions of the above-mentioned vege- table products. He first renders the solution alkaline, then adds solution of sulphate of copper to it, and either heats the mixture or leaves it for some time in the cold. By pursuing his directions, I encountered contradictory results ; but, by the following method, I have secured uniform success, in applying the criteria, and have even arrived at a method of determining, by a direct test, the quantity of sugar in diabetic urine. I dissolve a weighed portion of sulphate of copper in a measured quantity of water, and make the solution faintly alkaline, as tested with turmeric paper, by the addition 7^ SUGAR. of potash Ije, in the cold; for if the mixture be hot, a portion of the disengaged green hydrate of copper is converted into black oxide. This mixture being always agitated before applying it, forms the test liquor. If a few drops of it be introduced into a lolution of gum, no change ensues on the hydrate of copper, even at a boiling heat, which 9how8 that a gummate of copper is formed, which resists decomposition ; but the cupreous mixture, without the gum, is rapidly blackened at the boiling tempera- ture. I do not find that the gummate is re-dissolved by an excess of water, as 'fi'om- mer affirms. Starch and tragacants comport like gnm, in which respect I agree with Trommer. Starch, however, possesses already a perfect criterion, in iodine water. Mr. Trommer Bays, that solution of dextrine affords a deep glue-colored liquid, without a trace of precipitate ; and that when his mixture is heated to 85° C, it deposites red grains of protoxide of copper, soluble in muriatic acid. I think these phenomena are dependant, in some measure, upon the degree of alkaline excess in the mixture. I find, the solu- tion of dextrine, treated in my way, hardly changes in the cold ; but when heated slightly, it becomes green, and by brisk boiling an olive tint is produced. It thus be- trays its tendency of transition into sugar. Solution of cane-sugar, similarly treated, undergoes no change in the cold at the end of two days ; and very little change of color even at a boiling heat, if not too concen- trated. Cane-sugar, treated by Trommer in his way, becomes of a deep blue; it can be boiled by potash in excess, without any separation of orange-red oxide of copper. Starch or grape-sugar has a marvellous power of reducing the green hydrate of copper to the orange oxide. I find, however, that it will not act upon the pure blue hydrate, even when recently precipitated ; it needs the addition, in every case, of a small portion of alkali. Yet ammonia does not seem to serve the purpose; for, in using the ammonia-sulphate of copper, in solution, I obtained unsatisfactory results with the above vegetable products. The black oxide of copper is not affected by being boiled in solution of starch-sugai. ** If solution of grape-sugar," says Trommer, " and potash, be treated with a solution of sulphate of copper, till the separated hydrate is redissolved, a precipitate of red oxide will soon take place, at common temperatures, but it immediately forms, if the mixture is heated. A liquid containing of grape-sugar, even one millionth „ , . 100 0^ part," says he, " gives a perceptible tinge (orange), if the light is let fall upon it." To obtain such a minute result, very great nicety must be used in the dose of alkali, which I have found it extremely difficult to hit. With my regulated alkaline mixture, how- ever, I never fail of discovering an exceedingly small proportion of starch-sugar, even when mixed with Muscovado sugar; and thus an excellent method is afforded of de- tecting the frauds of the grocers. I find that manna deoxidizes the green hydrate of copper slowly when heated, but not nearly to the same extent as grape-sugai*, which reduces it rapidly to the orarge oxide. If an excess of the hydrate of copper test be used, there will he a deposite of green hydrate at the bottom of the vessel, under the orange oxide. To apply these researches to the sugar of diabetic urine : This should first be boiled briskly to decompose the urea, and to dissipate its elements in the form of am- monia, as well as to concentrate the saccharine matter, whereby the test becomes more efficacious. Then add to the boiling urine, in a few drops at a time, the cupreous mixture, containing a known quantity of sulphate of copper, till the whole assumes a greenish tint, and continue the heat until the color becomes bright orange. Should it remain green, it is a proof that more hydrate of copper has been introduced than has been equivalent to the deoxidizing power of the starch-sugar. I have found that one grain of sulphate of copper in solution, supersaturated very slightly with potash, is de- composed with the production of orange protoxide, by about 3 grains of potato-sugar; or, more exactly, 30 parts of the said sulphate, in the state of an alkaline hydrate of copper, pass altogether into the state of orange oxide, by means of 100 parts of granular •tarch-sugar. Thus, for every 3 grains of sulphate so changed, 10 grains of sugar may be estimated to exist in diabetic urine. Acetate of copper may be used in the above experiments, but it is not so good as the sulphate. The chloride of copper does not answer. Specific gravity is also an important criterion, applied to sugars ; that of the cant and beet-root is 1-577 ; that of starch-sugar, in crystalline tufts, is 1-39, or perhaps 1-40, as it varies a little with its state of dryness. At 1-342, syrup of the cane contains 70 per cent, of sugar ; at the same density, syrup of starch-sugar contains 75| per cent, of concrete matter, dried at 260° F., and therefore freed from the 10 per cent, of water which it contains in the granular state. Thus, another distinction is obtained between the two sugars, in the relative densities of their solutions, at like saccharine contents per cent. SUGAR. 781 A very simple method of improving the quality of sugar has been proposed by Messrs. Oxland, of Plymouth, chemists, for defecating the juice of beet-root and of the cane. It consists in the use of acetate of alumina, of which they say that four pounds of the earth dissolved in acetic acid are sufficient for one ton of Jamaica sugar, without any peculiarity of treatment in the boiling or filtration. I should fear that the acid might be apt to weaken the grain or crystalline force of the sugar. When nearly all the acetic acid is driven off by the boiling of the syrup, a solution of tan, made by digesting 1 pound of crushed valonia in 2 gallons of hot water, is filtered hot into the syrup. Fermentable property of different kinds of Sugar. There is a remarkable difference between the fermentable property of cane sugar and grape sugar, which has not hitherto been sufficiently noticed, no mention being made of it in chemical works. It is, that s solution of grape sugar requires but a very small quantity of ferment to induce alcoholic fermentation, while solution of cane sugar requires a large quantity. When a solution is made of the same quantities of cane sugar and grape sugar in equal proportions of distilled water, it will be necessary to add at least eight times as much of the same ferment to induce alcoholic fermentation in the solution of cane sugar as in that of grape sugar. Under the action of a larger quantity of ferment, cane sugar is transformed into grape susar, and this latter appears to be the only substance susceptible of being de- composed by ferment into carbonic acid and alcohol. If a solution of cane sugar be brought into the state of alcoholic fermentation, and the action be stopped some time before the decomposition of the sugar is completed, by the addition of a large quantity of strong alcohol, it will be found that the remaining undecomposed sugar has been transformed into grape sugar. The fermentable property of sugar depends then upon the same causes as that of starch, several kinds of gum, and sugar of milk. These substances are transformed into grape sugar under the influence of different agents ; but of all vegetable matters susceptible of undergoing this transformation, grape sugar is undoubtedly that in which the change is eflfected with the greatest ease and promptitude. Indeed, it so readily undergoes the alcoholic fermentation that it has been classed among fermentable sugars, but it has no more right to this title than starch, several kinds of gum, and sugar of milk. Another invention of Messrs. Oxland for improvements in the manufacture and re- fining of sugar (patented in May, 1851), consists in the use of phosphoric acid in a com- bined state for defecating saccharine liquids, or solutions of sugar, and removing the color of the same. On the 26th of April, 1849, the present patentees obtained a patent for defecating and removing the color from solutions of sugar by the employment of acetate of alumina. In the specification of such patent, lime was directed to be used for effecting the separation of the alumina ; but it has been found that, even when care is observed, some alumina is liable to be left in solution. When acetate of alumina and lime have been used, the patentees effect the removal of the remaining alumina by the use of superphosphate of alumina or superphosphate of lime, by simply adding a small quantity of either of these substances to the syrup after the completion of the process with acetate of alumina, as described in the former specification, then boiling for two or three minutes, carefully neutralizing the excess of acid, by the addition of aluminate of lime, saccharate of lime, lime of water, or milk of lime ; and, when it has been ascertained that alumina is completely separated, completing the process in the manner described in the former specification. In place of using acetate of alumina, either alone or combined with phosphoric acid, a6 above explained, phosphates may be employed directly ; and they are capable of pro- ducing similar effects to those resulting from the use of acetate of alumina, with the advantage that the whole of the agent employed is separated from the saccharine matters. In treating a saccharine liquid, or solution of sugar, (say, for example, an ordinary sample of Mauritius sugar), the patentees dissolve it by blowing-up with steam in the usual wav, but avoiding the use of blood, and adding a soluble phosphate to the water employea ; if crystallized phosphate of soda be used, it should be in the f)roportion of one pound ana a half thereof for each ton of sugar. The saccharine iquid is brought to the boiling point, — any acidity being neutralized with aluminate of lime, saccharate of lime, lime water, or milk of lime ; and then the syrup thus obtained (which will be of the specific gravity of from 25** to 30** Baum^) is passed through the ordinary bag-filters. The sugar is, by this means, thoroughly defe- cated, — the feculent matters being left in the bags, from which the last trace of sugar may be removed by passing clean water through them. The weak solutions obtained in this way may be used for blowing up fresh quantities of raw sugar. As part of the color is removed from the syrup by the above described operation, it may be considered sufficient treatment previous to boiling in the vacuum-pan, or otherwise, for crystalliza- 782 SUGAR. SUGAR. 783 tl 1 tion ; but a farther amount of color may be removed by the use of from 6 to 8 per cent, or more, of hydrate of alumina (which has been dried at a temperature of 212° Fahr.,) diffused through the water used in blowing up the sugar ; and, by this means, the use of animal charcoal will be rendered unnecessary. The residuary alumina left in the filter bags, after the whole of the saccharine matter has been washed out, may be dried, and the organic matter removed by ignition ; and, after further washing, to remove any residuary soluble saline substance, it may be employed for manufacturing hydrate or superphosphate of alumina ; or, after the first-mentioned washing, previous to ignition, it may be used over again, with the addition of a further quantity of hy- drate of alumina. When superphosphate of alumina is used, it is mixed, in solution, with the water Tised in blowing-up the raw sugar, in the proportion of six pounds of alumina dissolved in phosphoric acid for each ton of sugar; and while the syrup (at from 25^ to 30° Baume), is being brought to the boiling point, any acidity is neutralized by the addition of aluminate of lime, saccharate of lime, lime water, or milk of lime. The syrup is then passed through the bag-filters, and the clear syrup conducted into the receiver that supplies the vacuum or other boiling pan. The subsequent operations are the same as in the old plan of working. The matters left in the filter-bags are treated aa above described, to remove any remaining saccharine matter. The patentees prepare the superphosphate of alumina by dissolving alumina in phosphoric acid, in the following manner: — They burn bones white, grind them to fine powder, and digest the product in sufiicient muriatic acid for the solution of the car- bonate of lime only ; and then they dry the residue, after carefully washing it, to remove every trace of soluble matter. To a given weight of this residue, mixed with enough "Water to make a thin paste (in a shallow earthenware tank or vessel), they add a quantity of pure sulphuric acid, sufficient to combine with nearly all the lime present, «. e., all except 2 or 3 per cent. ; stirring the mixture well and keeping it warm (say above 90° Fahr.), for about 24 hours, and after this they lixiviate the mass with water until all the soluble matters are separated from the sulphate of lime. The strong liquors, obtained in this way, may be used for combining with alumina, and the weak solutions for lixiviating fresh quantities of phosphoric acid in course of manufacture. When alumina is digested in the phosphoric acid, produced in the manner above de- scribed, phosphate of alumina, insoluble in water, is first formed; and by dissolving this in a quantity of phosphoric acid sufficient only for that purpose, superphosphate of alumina is obtained, which should be filtered previous to use. Aluminate of lime is prepared by dissolving alumina in caustic potash or soda, and then hy the addition of lime water or milk of lime, precipitating aluminate of lime, which is to be carefully washed. When required for use, the patentees diffuse the aluminate of lime through water, and they prefer to employ it instead of saccharate of lime, or milk of lime or lime water. When making sugar from the cane, they defecate the juice with aluminate of lime in the usual way, neutralizing any excess of lime with superphosphate of alumina or superphosphate of lime ; then, after filtering and concentrating the filtered liquid to firom 25° to 30° Baume, they treat the syrup with phosphate of soda in the same man- ner as described with respect to raw sugars; and after a second filtration, they boil in the usual way. In the manufacture and refining of beet-root sugar, they proceed as above described for cane sugar, only using a larger quantity of aluminate of lime or milk of lime in the first defecation. The patentees state that thev do not confine themselves to the details above given, Dr to the phosphates mentioned, as others may be substituted; but what they claim is, the employment of phosphoric acid in a combined state, as above described.— -i^ew- ton s Journal, vol xl., p. 27. Sugar tested hy bichromate of potash. If a thick pure cane sugar syrup be mixed w-ith a boiling solution of bichromate of potash in a test tube, and then withdrawn from the heat, a deep green color will appear, especially on dilution with water. Other kinds of sugar remain indifferent to the bichromate. No change takes place in It with starch sugar, and if this be mixed with cane sugar, it protects the latter from being colored a dark green. Nitrate of cobalt added to cane sugar alkalized produces a bluish violate precipitate ; but not with an alkalized (potash) grape 8ugar.--i2«.'A. SvoAB in Four Ports of Gbkat BarrAm, for the Ten Months ending Slst October, 1851 and 1852.* British Plantation. West India • . . Mauritius East Indta • Total British Plantation - Foreign. Manilla, &c. ... Brazil . . . . Cuba . . . . Porto Rico, tc. Total Foreign Total British Plantation Total Sugar ... Molasses (reduced to Sugar) Total - . . . Import. | Duty Paid. j Export. Stock. | 1851. 1852. 1851. 1852. 1851. 1&52. 1851. 1852. Tons. 120,800 45,400 54,600 Tons. 143,300 49,000 49,500 Tons. 93,800 38,400 50,300 Tons. 136,400 47,100 61,800 Tons. Tons. Tons. 41,000 14,700 28,800 Tons. 40,100 14,700 24,900 220,800 241,800 187,500 245,300 — — 84,500 79,100 12,700 34,500 38,800 17,300 5,800 11,400 20,400 6,600 3,300 11,600 25.100 15,700 1,000 1,900 15,2(t0 7,000 5,600 7,000 4,800 1,400 4,100 8,600 9,400 3,100 11,200 25.100 27.500 6,800 8,500 16,600 20,700 3,500 103,300 220,800 44,200 241,800 55,700 187,500 2.5,100 245,300 270,400 14,600 18,800 25,200 70,600 84,500 49,300 79,100 324,100 16,300 286,000 11,300 243,200 15,500 18,800 25,200 155,100 11,800 128,400 6,000 340,400 297,300 258,700 285,000 18,800 25,200 166,900 134,400 SuOAB in EuROPr^ including Gbkat Betfain, for the Ten Months ending 3l8t October, 1860, 1851, and 1852. Holland . . . Antwerp . . . Hamburgh . . • Bremen . . . Havre . . . . Trieste . . . . Genua . . . . Leghorn . . . Total Continent . Great Britain Total Europe • Import. Stock. 1850. 1851. 1852. 1850. 1851. 1352. Tons. Tons. Tons. Tons. Tons. Tons. 95,600 97,660 86,100 8,400 13.710 6,400 30,720 13,660 19,540 2,060 3,870 2,080 25,250 23,500 20,250 5,750 8,750 4,250 6.500 7,750 4,460 300 1,300 300 23,650 20,360 37,120 4,770 2,830 10,670 43,870 26,490 39,270 18,810 10,310 10,410 17,230 8,290 14,630 4.690 3,300 2,780 7,050 3,540 7,330 1,360 810 850 249,870 201,250 228.700 46,140 44.880 37,740 290,780 340,400 297,300 118,540 166,900 134,400 540,650 541,650 ' 526,000 164,680 211,780 172,140 Sugar in United Kingdom (refined, or equal to refined). Years. Import. Consumption. Export Tons. Tons. Tons. 1847 4,820 1,260 2,930 1848 11,040 2,220 6,130 1849 15.220 8,070 9,900 1850 17,890 5,8^40 4,620 1851 21,930 16,930 2,650 Molasses. Years. Import Consumption. Export 1847 1848 1849 1860 1851 Tons. 47,490 25,890 63.130 45,250 89,560 Tons. 31,930 31,850 40,620 45,880 33,650 The exports of mo- lasses are very in- significant. * For these important tables, I am indebted to James Cook, Esq., of Mbicing Lane. 784 SUGAR. SUGAR. 785 III ^mmm 00 r4 »-H cc * CO -* • 00 I-H l-H _ o «o o >o o o © © © 9 © r1 i Jtr- 1— • CO t- CO (N to CO l-H •^ CO *-H to l-H to l-H t 1 00 00 CO CO © to -* •^ © * o CO CO I-l CO o t- o (N r- © CO l-H (N CO I i o 1-^ CO .-H l-H l-H l-H OQ o • t- "«*< © to CO r-i l-H CO l-H rH ett d l-H l-H »•< to 00 a» on t- «-l o Tt< t^ © OS (N I-H l-H os I t i 1 i:— "«*< f-H CO 00 00 OS © 00 l-H l-H 09 © 00 I-l l-t I-H 97 OS Tt* O 00 to © l-H © (M to © s 1— 1 ■ »o CO t- 00 00 © 00 (M CO &• ^ o t- .t- CO o (N CO OS to © 1-t 1 o CO T^ O to to 00 CO CO © to ^d l-H • (M :. ■ i. 1 « 1 a 9 »0 CO a a a o a a 1 a s t § I o • OQ 00 o 1?> B2 cl a S o •s c8 1^ J3 3 C8 3 00 <8 •3 o 2 Hi HJ 3 m n n EcH c:) o QO « ^ PQ 786 SUGAR OF LEAD. Sugar in United Kingdom (unrefined, or not equal to refined). SULPHATE OF IRON. 787 Year*. Imports. Consumption. Exports Baw. Refined in Bond. Tons. Tons. Tons. Tona 1840 201,790 179,740 11,480 11,760 1841 245,260 202,880 21,270 15,610 1842 237,800 193,420 20,090 13,740 1843 261,030 201,410 28,680 13,000 1844 244,000 206,470 16,690 10,960 1845 291,040 242,830 30,800 13,690 1846 281,130 261,010 12,040 11,880 1847 410,480 288,980 40,200 11,460 1848 343,600 307,120 16,630 12,440 1849 346,290 296,110 27,930 11,160 1850 314,570 804,570 18,490 10,460 1851 397,010 312,770 15,340 12,930 Months 1852. England. Hamburg. France. United States. Holland. West Indies. ChilL Callao. Total. January February March April May June July August September Ql9. 37,141 19,527 22,065 46,493 5,500 42,169 64,096 14,777 Qls. 4,002 7,040 25,130 2,000 14,628 Qls. 4,211 11,000 12,570 6,029 7.000 5,600 Qk 6,126 17,633 11,180 Qls. 7,499 5,473 ~ ~ 6,500 Qls. 2,287 Qls. 1,100 Qls. 837 900 Qls. 51,866 29,594 45,709 29,095 84,193 14,000 62,826 71,933 21,277 251,758 62,800 46,410 34,939 19,472 2,287 1,100 1,737 410,493 SUGAR OF LEAD, properly jJcetate of lead (Jcetate de plomb ; Sel de SatumBf Fr. ; Essigsaures Bleioxyd, Bleizucker, Germ.), is prepared by dissolving pure litharge, with heat, in strong vinegar, made of malt, wood, or wine, till the acid be saturated. A copper boiler, rendered negatively electrical by soldering a strap of lead within it, is the best adapted to this process on the great scale, 325 parts of finely ground and sifted oxyde of lead, require 575 parts of strong acetic acid, of spec. grav. 7** Baume, for neutralization, and afford 960 parts of crystallized sugar of lead. The oxyde should be gradually sprinkled into the moderately hot vinegar, with constant stirring, to pre- vent adhesion to the bottom ; and when the proper quantity is dissolved, the solution may be weakened with some of the washings of a preceding process, to dilute the acetate, after which the whole should be heated to the boiling point, and allowed to cool slowly, in order to settle. The limpid solution is to be drawn off by a syphon, concentrated by boiling to the density of 32° B., taking care that there be always a faint excess of acid, to prevent the possibility of any basic salt being formed, which would interfere with the formation of regular crystals. Should the concentrated liquor be colored, it may be whitened by filtration through granular bone black. Stoneware vessels, with salt glaze, answer best for cry stall izers. Their edges should be smeared with candle-grease, to prevent the salt creeping over them by efflortscent vegetation. The crystals are to be drained, and dried in a stove-room very slightly heated. It deserves remark, that linen, mats, wood, and paper, imbued with sugar of lead, and strongly dried, readily take fire, and burn away like tinder. When the mother waters cease to aflTord good crystals, they should be decomposed by carbonate of «oda, or by lime skilfully applied, when a carbonate or an oxyde will be obtained, fit for treating with fresh vinegar. The supernatant acetate of soda may be employed for the extraction of pure acetic acid. A main point in the preparation of sugar of lead, is to use a strong acid ; otherwise much time and acid are wasted in concentrating the solution. Tliis salt crystallizes in colorless, transparent, four and six-sided prisms, from a moderately concentrated solution; but from a stronger solution, in small needles, which have a yellow cast if the acid has been slightly impure. It has no smell, a sweetish astringent metallic taste, a specific fravity of 2*345; it is permanent in the air at ordinary temperatures, but efl3oresces when heated to 95®, with the loss of its water of crj'stailization and some acid, falling into a powder, which passes, in the air, slowly into carbonate of lead. The crystals dissolve in Ij times their weight of water at 60®, but in much less of boiling water, and in 8 parts of alcohol. The solution feebly reddens litmus paper, but has an alkaline reaction upon the colors of violets and turmeric. The constituents of the salt are, 58-71 oxyde of lea^ 27'08 acetic acid, and 14*21 water, in 100. Acetate of lead is much used in calico-printing. It is poisonous, and ought to be pre- pared and handled with attention to this circumstance. There are two subacetates of lead ; the first of which, the ter-subacetate, has three atoms of base to one of acid, and is the substance long known by the name of Grouiard's extract. It may be obtained by digesting with heat a solution of the neutral acetate, upon pure litharge or massicot. The solution affords white crystalline scales, which do not taste so sweet as sugar of lead, dissolve in not less than 30 parts of water, are insolu- ble in alcohol, and have a decided alkaline reaction upon test paper. Carbonic acid, transmitted through the solution, precipitates the excess of the oxyde of lead, in the state of a carbonate, a process long ago prescribed by Thenard for making white-lead. This subacetate consists of 88-66 of oxyde, and 13-34 acid, in 100 parts. It is employed for making the orange sub-chromate of lead, as also sometimes in surgery. A sex-subacetatey containing 6 atoms of base, may be obtained by adding ammonia in excess to a solution of the preceding salt, and washing the precipitate with dilute water of ammonia. A white powder is thus formed, that dissolves sparingly in cold water, but gives a solution in boiling water, from which white silky needles are de- posited. It consists of 92-86 oxyde, and 7-14 acid. SULPHATES, are saline compounds of sulphuric acid with oxydized bases. The ininutest quantity of them present in any solution, may be detected by the precipitate, insoluble in nitric or muriatic acid, which they afford with nitrate or muriate of baryta. They are mostly insoluble in alcohol. SULPHATE OF ALUMINA AND POTASSA, is alum. SULPHATE OF AMMONIA, is a salt sometimes formed by saturating the ammonia liquor of the gas-works with sulphuric acid ; and it is employed for making carbonate of ammonia. See Ammonia and Sal Ammoniac This salt, now so extensively used in preparing artificial manures and imitations of guano, for farmers, is made of great purity, and at an economical rate, by the patent process of Mr. Evans, described under the article Gas. A mixture of 10 per cent of this sulj)hate with 20 of bone-dust, some gypsum and farmyard manure, will form a very fertilizing composts applicable to a great variety of soils. SULPHATE OF BARYTA, is the mineral called heavy-spar, which frequently forms the gangue or vein-stone of lead and other metallic oreai SULPHATE OF COPPER, Roman or Blue Vitriol (Vitriol de Chypre, Fr. ; Kmp~ fervitriol, Germ.), is a salt composed of sulphuric acid and oxyde of copper, and may be formed by boiling the concentrated acid upon the metal, in an iron pot. It is, how- ever, a natural product of many copper mines, from which it flows out in the form of a blue water, being the result of the infiltration of water over copper pyrites, which has become oxygenated by long exposure to the air in subterranean excavations. The liquid is concentrated by heat in copper vessels, then set aside to crystallize. The salt forms in oblique four-sided tables, of a fine blue color; has a spec, gravity of 2*104; an acerb, disagreeable, metallic taste ; and, when swallowed, it causes violent vomiting. It be- comes of a pale dirty blue, and effloresces slightly, on long exposure to the air; when moderately heated, it loses 36 per cent, of water, and faHs into a white powder. It dis- solves in 4 parts of water, at 60°, and in 2 of boiling water, but not in alcohol ; the solu- tion has an acid reaction upon litmus paper. When strongly ignited, the acid flies off, and the black oxyde of copper remains. The constituents of crystallized sulphate of copper are— oxyde, 31-80; acid, 32*14; and water, 36-06. Its chief employment in this country is in dyeing, and for preparing certain green pigments. See Scheele's and ScHWEiNFURTH Green. In Fraucc, the farmers sprinkle a weak solution of it upon their grains and seeds before sowing them, to prevent their being attacked by biids and insects. SULPHATE OF IRON, Green vitriol, Copperas {Couperose verte, Fr. ; Eisen-vitriol, Schwefelsures Eisenoxydul, Germ.), is a crystalline compound of sulphuric acid and protoxyde of iron; hence called, by chemists, the protosulphate ; consisting of, 26-10 of base, 29*90 of acid, and 44*00 of water, in 100 parts; or of 1 prime equivalent of protoxyde, 36, -|- 1 of acid, 40, -|- 7 of water, 63,= 139. It may be prepared by dis- solving iron to saturation in dilute sulphuric acid, evaporating the solution till a pel- h'cle forms upon its surface, and setting it aside to crystallize. The copperas of eommerce is made m a much cheaper way, by stratifying the pyrites found in the eoal 788 SULPHATE OF IRON. SULPHOSELS. 789 iii i I ineasiires (VUridkies and SlrahVcies of the Germans), upon a sloping puddled platform of stone, leaving the sulphuret exposed to the weather, till, by the absorption of oxygen, il effloresces, lixiviating with water the supersulphate of iron thus formed, saturating thi* excess of acid with plates of old iron, then evaporating and crystallizing. The other pyrites, which occurs often crystallized, called by the Germans Schwefelkies or EisenkieSf must be deprived of a part of its sulphur by calcination, before it acquires the property of absorbing oxygen from the atmosphere, and thereby passing from a bisulphuret into a bisulphate. Alum schist very commonly contains vitriolkies, and affords, after being roasted and weather-worn, a considerable quantity of copperas, which must be carefully •eparated by crystallization from the alum. This liquor used formerly to be concentrated directly in leaden vessels; but the first stage of the operation is now carried on in stone canals of considerable length, vaulted over with bricks, into which the liquor is admitted, and subjected at the surface to the action of flame and heated air, from a furnace of the reverberatory kind, constructed at one end, and discharging its smoke by a high chimney raised at the other. See Soda Manufacture. Into this oblong trough, resting on dense clay, and rendered tight in the joints by water-cement, old iron is mixed with the liquor, to neutralize the excess of acid generated from the pyrites, as also to correct the tendency to superoxydizement in copperas, which would injure the fine green color of the crystals. After due concen- tration and saturation in this surface evaporator, the solution is run off into leaden boilers, where it is brought to the proper density for afibrding regular crystals, which it does by slow cooling, in stone cisterns. Copperas forms sea-green, transparent, rhoroboidal prisms, which are without smell, but have an astringent, acerb, inky taste ; they speedily become yellowish-brown in the air, by peroxydizement of the iron, and effloresce in a warm atmosphere : they dissolve in 1'43 parts of water at 60°, in 0*27 at 190°, and in their own water cf crystal- lization at a higher heat. This salt is extensively used in dyeing black, efei>ecially hats, in making ink and Prussian blue, for reducing indigo in the blue vat, in the China blue dye, for making the German oil of vitriol, and in many chemical and medicinal preparations. There is a persulphate and subpersulphate of iron, but they belong to the domain of chemistry. The first may be formed, either by dissolving with heat one part of red oxyde of iron (colcothar) in one and a half of concentrated sulphuric acid, or by adding some nitric acid to a boiling>hot solution of copperas. It forms with galls and logwood a very black ink, which is apt to become brown-black. When evaporated to dryness, it appears as a dirty white pulverulent substance, which is soluble in alcohol. Il con- sists, in 100 parts, of 39*42 of red oxyde of iron, and 60*58 sulphuric acid. Hydrated peroxyde of iron, prepared by precipitation with alkali from solution of the persulphate, is an excellent antidote against poisoning by arsenic. A Trench perruquier, who had swallowed two drachms of arsenious acid, was, after an interval of twenty minutes, treated with the oxyde precipitated from 6 ounces of that salt by caustic potash. It was diffused in 20 quarts of weak sirup, and administered in successive doses. After repeat* ed vomiting and purging, the patient felt no more pain, and was pronounced by the phy- sician to be quite convalescent. In the copperas and alum works, a very large quantity of ochrey sediment is obtained; which is a peroxyde of iron, containing a little sulphuric acid and alumina. This de- posite, calcined in reverberatory hearths, becomes of a bright-red color ; and when ground and elutriated, in the same way as is described under uhite lead, forms a cheap pigment, in very considerable demand, called English red, in the French market. Colcothar of Vitriol, and Crocus of Mars, are old names for red oxyde of iron. Thi» brown-red powder is obtained in its purest state, by calcining dried sulphate of iron in a furnace till all its acid be expelled, and its base become peroxydized. It must be levi- gated, elutriated, and dried. This powder is employed extensively in the steel manufac- ture, for giving the finishing lustre to fine articles ; it is used by silversmiths under the name of plate powder and rouge ; and by the opticians for polishing the specula of reflecting telescopes. Much of the crocus in the market, is made, however, from the cop- peras and alum sediments, and is greatly inferior to the article prepared by the last pro- cess. The finest rou^z is made by precipitating the oxyde with soda, then washing and calcining the powder. An excellent powder for applying to razor-strops, is made by igniting together in a crucible equal parts of well-dried copperas and sea salt. The heat must be slowly raised and well regulated, otherwise the materials will boil over in a pasty state, and the product will be in a great measure lost. When well made, out of contact of air, it has the brilliant^pect of plumbago. It has a satiny feel, and is a true fer olegisUf similar in composition to the Elba iron ore. It requires to be ground and elutriated { after which it afl^ords, on drying, an impalpable powder, that may be either rubbed on a strop of smooth bufif leather, or mixed up with hog's-lard or tallow into a stifi cerate. SULPHATE OF LIME. See Gypsum. SULPHATE OF MAGNESIA, Epsom Salt (Sel amer, Fr. ; Bittersatz, Germ.), exists in sea-water, as also in the waters of Saidschiitz, Sedlitz, and PiiHna; and in many saline springs, besides Epsom in Surrey, whence it has derived its trivial name, and from which It was first extracted, in the year 1695, and continued to be so, till modem chem- istry pointed out cheaper and more abundant sources of this useful purgative salt. The sulphate of magnesia, occasionally found effloresced on the surface of minerals in crystalhne filaments, was called haarsalz (hair salt) by the older writers. The bittern of the Scotch sea-salt works is muriate of magnesia, mixed with a little sulphate of magnesia and chloride of sodium. If the proper decomposing quantity (found by trial) of sulphate of soda be added to it, and the mixed solution be evaporated at the tem- perature of 122° F., chloride of sodium will form by double affinity, and fall down in cubical crystals; while the solution of sulphate of magnesia which remains, being evaporated to the proper point, will afford regular crystals in four-sided prisms with four-sided acummations. Or, if bittern be treated in a retort with the equivalent quantity of sulphuric acid, the muriatic acid may be distilled oflfinto a series of Woulfe's bottles, and the, sulphate of magnesia, soda, and lime, wiU remain in the retort, from which mixture the sulphate of magnesia may be separated by filtration and crystalliza- tion. ^ Magnesian limestone being digested with as much muriatic acid as will dissolve out its lime only, will, after washing, afl'ord, with the equivalent quantity of sulphuric acid a pure sulphate of magnesia ; and this is certainly the simplest and most profitable procesc for manufacturing this salt upon the great scale. Many prepare it directly, by di<»esting upon magnesian limestone the equivalent saturating quantity of dilute sulphuric acid. The sulphate of lime being separated by subsidence, the supernatant solution of sulphate of magnesia is evaporated and crystallized. This salt is composed of, magnesia 16*72, sulphuric acid 32*39, and water 50-89 When free from muriate, it tends to effloresce in the air. It dissolves in four parts of water at 32°, in 3 parts at 60°, in 1*4 at 200°, and in its own water of crystallization at a higher heat. SULPHATE OF MANGANESE is prepared on the great scale for the calico- pnnters, by exposing the peroxyde of the metal and pitcoal ground together, and made into a paste with sulphuric acid to a heat of 400° F. On lixiviating the calcined mass, a solution of the salt is obtained, which is to be evaporated and crystallized. It forms pale amethyst-colored prisms, which have an astringent bitter taste, dissolve in 2i parU So o^^^"*' ^^^ ^^^^^^^ ®^' protoxyde of manganese 31*93, sulphuric acid 35*87, and water 32*20, m 100 parts. ' SULPHATE OF MERCURY is a white salt which is used in making corrosive sublimate. See Mercury. The subsulphate, called Turbith Mineral, is a pale yeUow pigment, and may be prepared by washing the white sulphated peroxyde with hot water which resolves It into the soluble supersulphate, and the insoluble subsulphate, or Turirith It IS poisonous. ' SULPHATE OF POTASSA is obtained by first igniting and then crystalUzing the residuum of the distillation of nitric acid from nitre. SULPHATE OF SODA is commonly called Glauber's salt, from the name of the chemist who first prepared it. It is obtained by igniting and then crystallizing the resi- duum of the distillation of muriatic acid from common salt. It crystallizes in channeUed 6-sided prisms. See Soda Manufacture. SULPHATE OF ZINC, called also White Vitriol, is commonly prepared in the Harz, by washmg the ca cmed and effloresced sulphuret of zinc or blende, on the same principle as green and blue vitriol are obtained from the sulphurets of iroi and coddct Pure sulphate of zmc may be made most readily by dissolving the metal in dilute sulphni nc acid, evaporating and crystallizing the solution. It forms prismatic crystals which SULPHITES are a class of salts, consisting of sulphurous acid, combined in eauivalent proportions with the oxydized bases. a f » «t,iu, comoinea in equivalent SULPHOSELS is the name given by Berzelius to a class of salts which mar be rrverv'S'n^:;!-. ^T^^/ «*»' P-^^i^^ing of an oxydT and an LIJ (an o^Lo S.„r.tp7hvTniprrn V^ ''^^?''' *"^, ^T^ ^*^^«»g^ t»»« solution a stream 3^ sail phureted hydrogen, till the sa t be entirely decomposed. In this operation, the oxysaU firtlTlr.K ^'^^^^*«^^*>y the sulphur of the compound gas ; while its hydSg^ forms water with the oxygen of the saline base. This process is applicable only to the Xr 'LfhS'nrV""'-^ these not to the nitrates, carbonates, or phosphates. 2. Tn. other method of preparing sulphxtsalts is, to add to a watery solution of sulphuret of 790 SULPHUR. potassium, an electro-negative metallic sulphuret, which will dissolve in the liquid tii the sulphuret of potassium be saturated. This saline compound is to be employed to effect double decompositions with the oxysalts ; that is, to convert the radical of another b«se, combined with an oxacid^ into a sulphosalt. 3. If the electro-negative sulphuret be put in powder into a solution of the hydrosulphuret of potassa, it will dis- solve and expel the sulphureted hydrogen with effervescence : just as carbonic acid is displaced by a stronger acid. For his other three methods of preparing sulphosalts, see his ElementSy vol. iii. p. 336, Fr. translation. SULPHUR, Brimstone (Sou/re, Fr. ; Sckwe/el, Germ.), is a simple combustible, solid, non-metallic, of a peculiar yellow color, very brittle, melting at the temperature of 226* Fahr., and possessing, after it has been fused, a specific gravity of 1'99. M'hen held in a warm hand, a roll of sulphur emits a crackling sound, by the fracture of its interior parts; and when it is rubbed, it emits a peculiar well-known smell, and acquires vt the same time negative electricity. When heated to the temperature of 660° F. it takes fire, burns away with a dull blue flame of a suffocating odor, and leaves no residuum. When naore strongly heated, sulphur burns with a vivid white flame. It is not afl'ected by air T water. Sulphur is an abundant product of nature ; existing sometimes pure or merely mixed, and at others in intimate chemical combination with oxygen, and various metals, form- ing sulphates and sulphurets. See ores of Copper, Iron, Lead, &c., under these metals. Fig. 1417 represents one of the cast-iron retorts used at Marseilles for refining sul- phur, wherein it is melted and converted into vapors, which are led into a large chamber for condensation. The body a, of the retort is an iron pot, 3 feet in diameter outside, 22 inches deep, half an inch thick, which weighs 14 cwts., and receives a charge of 8 cwts. of crude sulphur. The grate is 8 inches under its bottom, whence the flame rises and plays round its sides. A cast-iron capital b, being luted to the pot, and coverei'wiih sand, the opening in front is shut with an iron plate. The chamber d, is 23 feet long, 11 feet wide, and 13 feet high, with walls 32 inches thick. In the roof, at each gable, valves or flap- doors, e, 10 inches square, are placed at the bottom of the chimney c. The cords for open- ing the valves are led down to the side of the furnace. The entrance to the chamber is shut with an iron door. In the wall opposite to the retorts, there are two apertures near the floor, for taking out the sulphur. Each of the two retorts belonging to a chamber is charged with 7^ or 8 cwts. of sulphur ; but one is fired first, and with a gentle heat, lest the brimstone froth should overflow; but when the fumes begin to rise copiously, with a stronger flame. The dis- tillation commences within an hour of kindling the fire, and is eompleted in six hours. Three hours after putting fire to the first retort, the second is in like manner set in operation. When the process of distillation is resumed, after having been some time suspended, explosions may be apprehended, from the presence of atmospherical air ; to obviate the danger of which, the flap-doors must be opened every ten minutes; but they should remain closed during the setting of the retorts, and the reflux of sulphurous fumes or acid should be carried off by a draught-hood over the retorts. The distillation is carried on without interruption daring the week, the charges being repeated four times in the day. By the third day, the chamber acquires such a degree of heat as to preserve the sulphur in a liquid state; on the sixth, its temperature becoming nearly 300° F., gives the sulphur a dark hue, on which account the furnace is allowed to cool on the Sunday. The fittest distilling temperature is about 248°. The sulphur is drawn off through two iron pipes cast in the iron doors of the orifices on the side of the chamber opposite to the furnace. The iron stoppers being taken out of the mouths of the pipes, the sulphur is allowed to run along an iron spout placed over red-hot charcoal, into the appropriate wooden moulds. Native stUphnr in its pure state is solid, brittle, transparent, yellow, or yellow bordei>^ SULPHUR. 791 inf on green, and of a glassy lustre when newly broken. It occurs frequently in crys- talline masses, and sometimes in complete and regular crystals, which are all derivaWe ' from the rhomboidai octahedron. The fracture is usually conchoidal and shining. Its specific gravity is 2*072, exceeding somewhat the density of melted sulphur. It possesses a very considerable refractive power ; and doubles the images of objects even across two parallel faces. Sulphur, crystallized by artificial means, presents a very remarkable phe- nomenon; for by varying the processes, crystals are obtained whose forms belong to two different systems of crystallization. The red tint, so common in the crystals of Sicily, and of volcanic districts, has been ascribed by some mineralogists to the presence of real- g€U", and by others to iron; but Stromeyer has found the sublimed orange-red sulphur of Vulcano, one of the Lipari islands, to result from a natural combination of sulphur and selenium. It is extracted from the minerals containing it, at Solfatara, by the following pro cess: — Ten earthen pots, of about a yard in height, and four and a half gallons imperial in o» pacity, bulging in the middle, are ranged in a furnace called a gallery; five being set on th^ one side, and five on the other. These are so distributed in the body of the walls of thj gallery, that their belly projects partly without, and partly within, while their top riset out of the vault of the roof. The pots are filled with lumps of the sulphur ore of the size of the fist; their tops are closed with earthenware lids, and from their shoulder proceeds a pipe of about two inches diameter, which bends down, and enters into another covered pot, with a hole in its bottom, standing over a tub filled with water. On applying heat to the gallery, the sulphur melts, volatilizes, and runs down in a liquid state into the tubs, where it congeals. When one operation is finished, the pots are re-charged, and the pro- cess is repeated. In Saxony and Bohemia, the sulphurets of iron and copper are introduced into lai^e earthenware pipes, which traverse a furnace-gallery ; and the sulphur exhaled flows into pipes filled with cold water, on the outside of the furnace. 900 parts of sulphuret afford from 100 to 150 of sulphur, and a residuum of metallic protosulphuret. See METAJXua ov and Copper. Volcanic sulphur is purer than that extracted from pyrites ; and as the latter is com- monly mixed with arsenic, and some other metallic impregnations, sulphuric acid made of it would not answer for many purposes of the arts; though a tolerably good sulphuric acid may be made directly from the combustion of pyrites, instead of sul[«/iur, in the lead chambers. The present high price of the Sicilian sulphur is a great encouragement to its extraction from pyrites. It is said that the common English brimstone, such as was extracted from the copper pyrites of the Parys mine of Anglesey, contained fully a fif- teenth of residuum, insoluble in boiling oil of turpentine, which was chiefly orpiment ; while the fine Sicilian sulphur, now imported in vast quantities by the manufacturers of oil of vitriol, contains not more than three per cent, of foreign matter, chiefly earthy, but not at all arsenical. Sulphur has been known from the most remote antiquity. From its kindling at a mo- derate temperature, it is employed for readily procuring fire, and lighting by its flame other bodies not so combustible. At Paris, the preparation of sulphur matches constitutes a considerable branch of industry. The sulphurous acid formed by the combustion of sulphur in the atmospheric air, is employed to bleach woollen and silken goods, as also cotton stockings; to disinfect vitiated air, though it is inferior in power to nitric acid vapor and chlorine ; to kill mites, moths, and other destructive insects in collections of zoology ; and to counteract too rapid fermentation in wine-vats, &.c. As the same acid gas has the property of suddenly extinguishing flame, sulphur has been thrown into a chimney on fire, with the best effect; a handful / •*» being sometimes suflUcient. Sulphur is also employed for cementing iron bars in stone-, for taking impressions from seals and cameos, for which purpose it is kept previously melted for some time, to give the casts an appearance of bronze. Its principal uses, however, are for the manufactures of vermil- ion, or cinnabar, gunpowder, and sulphuric acid. See Metallurgy, page 157, for the description of Gahn's furnace for extracting sul- phur from pyrites. Pyrites as a bi-sulphuret, consisting of 45*5 parts of iron, and 54*5 of sulphur, may, by proper chemical means, be made to give oft" one half of its sulphur, or about 27 per cent, j but great care must be taken not to generate sulphurous acid, as is done very wastefulljr by the Fahlun and the Groslar processes. By the latter, indeed, not more than one or two parts of sulphur are obtained, by roasting 100 part: of the pyritous ores of the Rammels- berg mines. In these cases, the sulphur is burned, instead of being sublimed. The re- siduum of the operation, when it is well conducted, is black sulphuret of iron, which may be profitably employed for making copperas. The apparatus for extracting sulphur from pyrites should admit no more air than is barely necessary to promote the sublimation. Sicily produced last year 70,000 tons of sulphur, and Tuscany 1200; of which Great BriU 788 SULPHURIC ACID I i ■ ( I ^rnXnlTsVooTon;/""''' ''''^' other places, 6,000. In 1820, Great irJtafn «» SULPHURATION, is the process by which woollen, silk, and cotton eoods are ex, posed to the vapors of burning sulphur, or to sulphurous acid gas InTe aS Straw ot^r^"^""""' ' '"' '"'"''' ' '^"^^^ '''' ^^^^P api^atu^ well Spt^^^^^^^^ Sulphuring-rooms are sometimes constructed upon a great scale, in which blankets. stdd\:fla.":S"wrth'^''l""^^ '^ ^"^P^'^^^' ^^^^^y"P«" poles ;,rco^sTK^^^ should be flagged with a sloping pavement, to favor the drainage of the water that drops down from the moistened cloth. The iron or stoneware vessels, in which the sutphur ^ cordit'to thfH*" the corners of the apartment. They should be increased n number a" cord ng to he dimensions of the place, and distributed uniformly over it. The windo^ dZ- thPr? Jif "Ti i^"" """'n^^ ""^^^ *° '^"^ hermetically close. In the lower part of the e^ iv th.l..h • ^ T" ^P^"'"-.^'th a sliding shutter, which may be raised or low- ered by the mechanism of a cord passing over a pulley. iJrv^on^.h?r K^ "^r"'^ ?' sulphurous acid and azotic gases are let off, in order to W^.hL *^«"^"sl»«n. should be somewhat larger than the opening at the bottom. A InaL I W ^ '^'■"^' the noxious gases above the building, and diffuses them over a widi TathlnZ T^"''^" ^5;"| promoted by means of a draught-pipe of iron,- connected with an ordinary stove, provided with a valve to close its orifice when not kindled. nans ,t U kin^^^^^^^^ J proper quantity of sulphur being next put into the shallow lllr thV c ! '• ^ ^""^T^^ 1''°'' '' '^^'"^' «^ ^^" «« its shutter, while a vent-hole f!^l- F i '^ T"^ ^^ drawing its cord, which passes over a pulley. After a few minutes, when the sulphur is fully kindled, that vent-hole must be almost entirely ^t, by relaxing the cord ; when the whole apparatus is to be let alone for a sufficient fr«I!*fho^^r* K^ ^^v P*':'*'^^'"^ precautions is to prevent the sulphurous acid gas escaping from the chamber by the seams of the principal doorway. Tnis is secured by closing i1 imperfectly, so that it may admit of the passage of somewhat more air than can enter by Uie upper seanjs, and the smallest quantity of fresh air that can support the combustion. t.nf Zr ^ ^i?n *^ T'""^"; °^ ^'' "^y ^^ increased at pleasure, by enlarging the under vent-hole a httle, and quickening the fire of the drauffht-stove. «m«» fil^'^^^JI^ the entrance door of the apartment, for the discharge of the goods, a o^r f n^ r 1^^- ^'^K^^ '" 'i^ ^""^"-^^ ^"""«^^' *^^ vent-hole must be thrown entirely open and the sliding shutter of the door must be slid up, gradually more and more every 2?Thf f T ^'""•V, ?"^ ^"^"y ^'^ "^'"^^ ^P^» ^^^ * P^«P«^ time. By this me^s the a^ of the chamber will become soon respirable. . jy^^f^?^TF HYDROGEN, is a gas, composed of one part of hydrogen and six- teen parts of sulphur, by weight. Its specific gravity is M912, compared to air=l-0O0O. It is the active constituent of the sulphurous mineral waters. When breathed, it is very deleterious to animal life ; and being nearly twice as dense as air, it may be poured from us generating bottle into cavities; a scheme successfully employed by M. Thenard to de- stroy rats m their holes. SULPHURIC ACID, Vitriolic ^cid, or Oil of Vitriol, (^cide sul/urique, Fr. ; HnnT"^ T' ^T*^ ^^'f important product, the agent of many chemical operal tions, was formerly procured by the distillation of dried sulphate of iron, called green Jlni • "^f "^«. the corrosive liquid which came over, having an oily consistence, was denominated oil of vitriol. This method has been superseded in Great Britain, France! and most other countries, by the cox;.-,L-tion o^ sulphur along with nitre, in large InH M««!r ""^ ' • ^"o *^ ^^ ^°''"'^'" P''^*'^^s> ^h^'^" 's still practised at Bleyl in Bohemia, Md Nordhausen m Saxony, gives birth to some interesting results, I shall describe it Into a long horizontal furnace, or gallery of brickwork, a series of earthenware retorts. 01 a pear shape, is arranged, with curved necks fitted into stoneware bottles or conden- J!^*^» , ""^ ""^ *^ ^J}^^^^ "^ith sulphate of iron, which has been previously heated to mo-Jerate redness. The first product of the distillation, a slightly acidulous phlegm, is allowed to escape ; then the retort and receiver are securely luted together. The fire is •^LfL''^\l /""^^"^r 5"'^^^ ^°': ^^^'^y-^'* ^°""s, whereby the strong sulphuric acid is expelled, w the form of heavy white vapors, which condense in the cold receiver into an oily-looking liquid. The latter portions, when received in a separate refrigerator, fre- quently concrete into a crystalline mass, formerly called glacial oil of vitriol. About six. ty four pounds of strong acid may be obtained from six hundred pounds of copperas. It 18 brown-colored ; and varies in specific gravity from 1-842 to 1-896. Its boiling point 18 so low as 120° Fahr. When re-distilled in a glass retort, into a receiver surrounded with ice, a very moderate heat sends over white fumes, which condense into a soft solid. IB silky filaments, like asbestos, tough, and difficult fo cut. When this is exposed tf SULPHURIC ACID. 793 the air, it emits copious fumes of sulphuric (not sulphurous) acid. It bums holes m paper as rapidly as a red-hot iron. Dropped in small quantities into water, it excites a hissing noise, like ignited metal ; and in larger quantities, it occasions an explosion. By dropping a fragment of it into a poised vial containing water, and stoppering in- stantly, to prevent the ejection of liquid, by the ebullition which always ensues, I got a dilute acid, containing a known portion of the solid acid, from the specific gravity of which, as well as from its saturating power, I ascertained that the above solid sulphuric acid was truly anhydrous (void of water), consisting of 1 equivalent proportion of sul- phur, and 3 of oxygen ; or, by weight, of 16 of the A)rmer, and 24 of the latter. Thit acid makes a red solution of indigo. The production of sulphuric acid from sulphur and nitre may be elegantly illustrated by means of a glass globe with a stoppered hole at its side, and four bent glass tubes in- sened into a leaden cap in its upper orifice. The first tube is to be connected with a heated matrass, disengaging sulphurous acid from copper filings and sulphuric acid ; the second with a retort, disensraging more slowly deutoxyde of azote (nitric oxyde) from copper filings and nitric acid ; the third with a vessel for furnishing steam in a moderate current towards the end of the process, when no water has been previously admitted into the balloon ; the fourth tube may be upright, and terminate in a small funnel. Through the opening in the side of the globe, atmospherical air is to be admitted from lime tc ♦kne, by removing the stopper ; after which, the residuary lighter azote may be allowed to escape by the funnel orifice. The nitric oxyde first absorbs oxygen from the air, becomes, in consequence, nitrous acid vapor, which giving up one third of its oxygen to the sulphurous acid, converts this, with the aid of water, into sulphuric acid, while itself returning to the slate of nitric oxyde, is again qualified to take oxygen from the air, and to transfer it to the sulpharous acid gas; and thus in perpetual rotation. These oxygenating and disoxygenating pro- cesses continue until nearly the whole oxygen of the atmospheric air contained in the globe is consumed. Were there liitle aqueous vapor present, those gases would soon cease to operate upon each other ; for though the nitric oxyde became^ nitrous acid, this would oxygenate little of the sulphurous acid, because the three substances would con- dense into white crystals upon the sides of the balloon, like hoar frost upon a window- pane in winter. These indicate a deficiency of aqueous vapor, and an excess of nitrous acid. On the admission of steam, the crystals disappear, the sulphuric acid is liquefied, the nitrous acid is converted into nitric acid and nitric oxyde ; the former of which com- bines with the water, while the latter is converted by the atmospheric oxygen into nitrous acid vapor. A certain quantity of water is therefore requisite to prevent the formation of that crystalline compound, which condenses the nitrous acid, and renders it inoperative in transforming fresh portions of sulphurous acid into sulphuric. On these principles alone is it possible to oxygenate the sulphurous acid, by the nitrous acid resuming and surrendering a dose of oxygen. In perpetual alternation. It was MM. Clement and Desormes who first had the sagacity to trace these compli- cated changes. They showed that nitrous acid gas and sulphurous acid gas mixed, react on each other through the intervention of moisture ; that there resulted thence a combina- tion of sulphuric acid, deutoxyde of azote (nitrous gas), and water; that this crystalline Compound was instantly destroyed by more water, with the separation of the sulphuric acid in a liquid state, and the disengagement of nitrous gas; that this gas re-constituted nitrous acid at the expense of the atmospheric oxygen of the leaden chamber, and thus brought matters to their primary condition. From this point, starting again, the particles of sulphur in the sulphurous acid, through the agency of water, became fully oxygenated by the nitrous acid, and fell down in heavy drops of sulphuric acid, while the nitrous gas derived from the nitrous acid, had again recourse to the air for its lost dose of oxygen. This beautiful interchange of the oxygenous principle was found to eo on, in their ex- periments, till either the sulphurous acid, or oxygen in the air, was exhausted. They verified this proposition, with regard to what occurs in sulphuric acid chambers, by mixing m a crystal globe the three substances, deutoxyde of azote, sulphurous acid, and atmospheric air. The immediate production of red vapors indicated the transforma- tion of the deutoxyde into nitrous acid gas; and now the introduction of a very little water caused the proper reaction, for opaque vapors rose, which deposited white star- form cr>'slals on the surface of the glass. The gases were once more transparent and color- less; but another addition of water melted these crystals with effervescence, when ruddy rapors appeared. In this manner the phenomena were made to alternate, till the oxygen ofthe included air was expended, or all the sulphurous acid was converted into sul- phuric. The residuaiy gases were found to be nitrous acid gas and azote, without sul- phurous acid gis ; while unctuous sulphuric acid bedewed the inner surface ofthe globe. Hence, Ihey justly concluded their new theory of the manufacture of oil of vitriol to be demonstrated. In consequence of their discovery, the manufacture of this acid has received suck 794 SULPHURIC ACID. improvements, that a nearly double product of it may now be obtained from the same weight of materials. Indeed, the economy may be reckoned to be much greater; for one half of the more cosily ingredient, the nitre, formerly employed with a given weight of •alphur, suffices at present. ^ In the manufacture of sulphuric acid upon the great scale, two different systems of working were long prevalent ; the intermittent or periodical, and the continuous or uniform. Both were carried on in large leaden chambers. In the former, the cham- bers were closed during the period of combustion and gaseous combination, but were opened from lime to time to introduce fresh atmospheric air. This method is, I believe, generally abandoned now, on account of the difficulties and delays attending it, though it afforded large products in skilful hands. In the latter, a continuous current of air is allowed to enter at the oven in front of the chamber for the combustion of the sulphur, and there is a constant escape of nitrogen gas, with a little sulphurous acid gas, at the remote end of the roof. Fig. 1418 represents a sulphuric acid chamber, a, a, are the bi ick or j^one pillars upon which it rests ; fr, 6, are the sustaining wooden beams or joists ; c, is the chimney for the discharge of the nitrogen ; rf, is the roof, and c, the sole of the hearth for the combustion of the sulphur; /, is the cylindrical tunnel, or pipe of lead or cast iron, for conducting the gasiform materials into the chamber ; g, is the steam boiler ; and hy the steam-pipe. That plan is variously modified, by different oil of vitriol makers in this country and in France. Very frequently, the oven e, d, is not situated under the chamber, but is built at the end of it, as at t, and arched over with brick, the crown being 9 inches thick. The pipe/, 18 inches in diameter, is then placed outside of the chamber, being inserted into a brick chimney, and, turning rectangularly, enters it opposite k. The sole of the hearth e, is a thick plate of cast iron (not hollowed as shown in the figure), 5 or 6 feet long, and 3 or 4 broad, with a small fireplace constructed beneath it, whose smoke-flue runs outwards, under the floor, to the side wall of the building. The oven is in this case about 2 feet in height, from the sole to the roof; and it hat an iron door, about 12 inches by 15, which slides up and down in a tightly-fitted iron frame. This door is frequent- ly placed in the side of the oven, parallel to the long side of the leaden chamber. A stout collar of lead is bolted to the chamber, where the pipe enters it. A the middle of the side of the chamber, about 2 feet above the ground, a leaden trough is fixed, which serves as a syphon-funnel and water-trap for introducing water to the acid gases. Several manufacturers divide the chamber into a series of rectangular compartments, by parallel leaden screens, 10 or 12 feet asunder, and allow these compartments to com- municate by a narrow opening, or a hole 1 foot square, in the top and bottom of each screen alternately. Thus the fumes, which enter from the chimney-pipe over A:, will be forced, by the screen at 6, to descend to 1, and pass through the opening there, to get into the second compartment, whence Ihey will escape near the top at 2, thus circulating up and down, so as to occasion a complete agitation and intermixture of their hetero- geneous particles. Into the side of the chamber, opposite to the centre of each com- partment, a lead pipe enters, and proceeds towards the middle of the area, terminating in a narrow orifice, for discharging a jet of high-pressure steam from a boiler loaded with 40 pounds upon the square inch. This boiler should be placed under a shed exterior to the building. It deserves lo be noted, that the incessant tremors produced in this pipe by the escape of the steam, cause the orifice to contract, and eventually to close almost entirely, just as the point of a glass tube does when exposed directly to the flame of a blowpipe. Provision should therefore be made against this event, by the chemical engineer. Equidistant between the middle point and each end of the chamber, two round holet are cut out in its side, about 16 inches in diameter, and 2 feet from the floor ; the sheet SULPHURIC ACID. 795 %ad being folded back over the face of the strong deals which strengthen the chamber in that place. The edges of the holes are bevelled outwards, so as to fit a large conical plug of wood faced with lead, called a man-hole door. One or other of these doors is opened from tune to time, to allow the superintendent to inspect the process, or work- men to enter, after the chamber is well ventilated, for the purpose of making repairs. 1 he joists or tie-beams, that bind the rafters of the roof of both the leaden chamber and the house, must be at least 7 inches deep, by 3 broad, and of such length as to have tneir ends supported upon the outer waU, or the columnar supports of the roof, in case a number of chambers are enclosed together in parallel ranges under a vast shed. These beams, which lie two feet apart, suspend the leaden roof, by means of leaden straps soldered to its upper surface and edges. The sides of the chamber are sustained by means of similar leaden straps affixed to the wooden posts (uprights), 4 inches broad by 3 thick, placed two or three feet apart along the sides of the chamber ; resting on the ground Jjelow, and mortised into the tie-beams above. Some chambers rest upon a sand-floor; but they are preferably placed upon wooden joists, supported by pillars stretching over an open irea, as shown in the figure, into which the workmen may descend readily, to examine the bottona. . ' The outlet c, on the top of the chamber, is sometimes joined to a long pipe of lead laid nearly horizontally, with a slight inclination upwards, along the roof, for favoring the condensation and return of acid matter. „J^^ *^® extremity /, of the chamber, which, having a downward slope of 1 inch in every 20 feet, should stand from 3 to 6 inches (according to its length) lower than t, one leg of an inverted syphon pipe is fixed by fusion, into which the liquid of the chamber passing, wilJ show by Its altitude the depth on the bottom within. From the cup-shaped orifice of that bent-up pipe, the acid of the chamber is drawn off by an ordinary leaden syphon into the concentration pans. The sheet lead of which the sides and top are made should weigh from 5 to 6 pounds per square foot; that of the bottom should be nearly of double thickness. Having now detailed, with sufficient minuteness, the construction of the chamber, I shall next describe the mode of operating with it. There are at least two plans at present m use for burning the sulphur coutinuously in the oven. In the one, the sulphur is laid ?" i, ^ u **"* f.' ^P^9*=- 796 SULPHURIC ACID. SULPHURIC ACID. 797 I rni' M. Clement- Desormej. demonstrated the proposition relative to the influence of temnef^ tture l^ a decisive experiment. He took a glass globe, furnished with three twi^X and put a bH of ice into it. Through the first opening he then introducedsulnhuro^ «cid gas; through the second, oxygen ; and through thi third, nitrius gas (de""^^^^^^^ azote). VVhile the globe was kept cool, by being plunged in i'ced waterfno sulphuric acW was formed, though all the ingredients essential to its production were present Buron exposing the globe to a temperature of 100- Fahr., the four bodies began i^ediaTelvtS react on each other, and oil of vitriol was condens^ in visible stride "^^'^^^^^ ^^ The introduction of steam is a modern invention, which has vastly facilitated and increased the production of oil of vitriol. It serves, by powerful T«^ftation not o^^^^ to mix the different gaseous molecules intimately togelLl; but to impel Tern a^^^^^^^ each other, and thus bring them within the sphere of their mutual S icll StraS This ,s Its mechanical effect. Its chemical agency is still more important VsupplyTni; moisture a every point of the immense included space, it determines the forman\,n of hydrous sulphuric acid, from the compound of nitric, nitrous, sulphurous and Srv sul- phunc acids. No sooner is this reaction accomplished, than the nitrous gis resumes iU tlT' ^n '^^ ^^"^'""^"^ atmospherical current, and becomes a^a^ fiTto operate a like round of transmutations with sulphurous acid, steam, and oxygen. The ni ro-enSte^ which ough to be the only residuum in a perfectly regulated vifrio chambri^escapes bj Its relative lightness at the opening c, in the roof, or, more properly speaking is dfficed by the influx of the heavier gases at the entrance-pipe. ^PeaKing, is aisplaced On the intermittent plan, after the consumption of each charge, and condensation of Jhe product, the chamber was opened, and freely ventilated, so as VexpeHhe res duary azote, and replenish it with fresh atmospheric air. In this system there were four dS stages or periods:- J. Combustion for two hours; 2. Admission of sLam a nT^Sa for an hour and a half; 3. Conversion, for three hoursf duiinT wh cMnt'^val the ^ro^^^ fhZZf T^r'^ ^'^'^ ^^"i"" "'^^ *^"^^ ^*^^^^«"^« ^^ the bottom ; 4 Purging of ?he chamber, for three quarters of an hour. •«^"*g*"5 "i lac By the continuous method, sulphuric acid may be currently obtained in the chambers of the specific gravity 1-350, or 1-450 at most ; for, when stronger, it absorbs and r^talS permanently much nitrous acid gas; but by the int'ermittent, so^dense as 550^^^^^ 1-620 ; whence in a district where fuel is hi^h priced as near P.rio ♦»,; »k ^ mended itself by economy in the concentratio^n oKe a'c"."^' IT^{ B^^.l'Ta Jv'enTn" most parts of France however, where time, workmen's wages, an^nteres of caniLTaiS the paramoun considerations, manufacturers do not find it for their "nLSstneener^^^^ raise the density of the acid in the chambers above 1-400, or at most 1500 as the further increase goes on at a retarded rate, and its concentration from 1 400^1^600 Vnkiea pans, costs very little. " ' *" leaaen «/k ^^u""^ ^^l '^"^^j^^ ^^^'^"y ""^ ^'^^' '" ^'^^^ Britain, the liquid of the chambers is run ofl, by the syphon above described, into a leaden gutter or spout, which dSr'es it i^to a series of rectangular vessels made of large sheets of lead, of 12^14 lbs to the sL^e foot, simply folded up at the angles into pans 8 or 10 inches deep/restin- upon aTrSe made of a pretty close row of wrought-iron bars of considerable^rength, under wh7^ tllT ^'k ^ ^" k"^'^ f ^*^''- "^^^'^ *^°^'^ ^'•^ ^^»y <=heap, each pan ma^ have a^epk- If,n nfX ^^ ^*^^^t hey are somewhat dear, the flame, after passing under the lowest pan of the range, which contains the strongest acid (at about 1-600) pmceedsunwirds with a slight slope to heat the pans of weaker acid, which, as it concent?a?eTrs gmdu^^^^ diSMpated. The 3 or 4 pans constituting the range are thus placed in a straiaht Zp w each at a different level, terrace like; en gradins^s the French sS ^ ' **"^' *""' Platinu'ni^retorts, to u^derg'oTlrirncenfr^^^^^^^ Zl tt"speS"vitJt tsll Z ZrZTrtZfLlZhr^^^^^^^ -'^- -P-'t'f Xn%fass reform Tderthira Zl^f^ flVm^^pfatfrd Zl,\ fl^^'^adtra^^^rfrrmt '^ place, near to which it is most distant from the tLs L the relt^r PnH^ flTh^'. ^T with tolerable equality on the first and last retort in\he range When natin^ir^.f-n'' causes a safe, rapid, anS. ecrorif^con^e^tf^tlon'^o? ^Xt''^e\l' Z^ 7k^ '^":' /'u '^"™ '"'"r'"' ^""^ ^'^^ concentrated boilL-hot oil of vUrk)l ^re osier baskets lined with straw. Sometimes, however, the acid is cooled by running 5 •lowly off through a long platinum syphon, surrounded by another pipe filled with cold vater. Fig. 1419 shows my contrivance for this purpose. The under stopcock a, being shut, and the leg 6, being plunged to nearly the bottom of the still, the worm is to be filled with concentrated cold acid through the funnel c. If that stopcock is now shut, and a opened, the acid will flow out in such quantity as to rarefy the small portion of air in the 4^ ^^^^^^"^^^^^^Z ~F^ e "PP^*^ P*''^ °^ the pipe 6, suflSciently to make the ff \ J"^ \ 3 ^^t acid rise up over the bend, and set the syphon ^ inaction. The flow of the fluid is to be so regu- lated by the stopcock a, that it may be greatly cooled in its passage by the surrounding cold water in the vessel /, which may be replenished by means of the tube and funnel rf, and overflow at «. A manufacturer of acid in Scotland, who buiTH in each chamber 210 pounds of sulphur in 24 hours, being at the rate of 420 pounds lor 20,000 cubic feet (= nearly 2000 metres cube), has a product ol nearly 3 pounds of concentrated oil of vitriol foi every pound of sulphur and twelfth of a pound of nitre. The advantage of his process results, I con ceive, from the lower concentration of the acid in the chambers, which favors its more rapid produc- tion. The platinum retort admits of from 4 to 6 opera- lions in a day, when it is well mounted and man- aged. It has a capital of platinum, furnished with a short neck, which conducts the disengaged vapors into a lead worm of condensation ; and the liquid thus obtained is returned into the lead pans. Great care must be taken to prevent any particles of lead from getting into the platinum vessel, since at the tem- perature of boiling sulphuric acid, the lead unites with the precious metal, and thus causes holes in the retort. These must be repaired by soldering-on a plate of platinum with gold. Before the separate oven or hearth for burning the sulphur in contact with the nitr« was adopted, this combustible mixture was introduced into the chamber itself, spread oa iron trays or earthen pans, supported above the water on iron stands. But this plan was very laborious and unproductive. It is no longer followed. One of the characters of the good quality of sulphuric acid, is its dissolving indigo without altering its fine blue color. Sulphuric acid, when well prepared, is a colorless and inodorous liquid, of an oily aspect, possessing a specific gravity, in its most concentrated state, of 1*842, when re- distilled, but as found in commerce, of 1-845. It is eminently acid and corrosive, so that a single drop will communicate the power of reddening litmus to a gallon of water, and will produce an ulcer of the skin when allowed to remain upon it. If swallowed in its strongest state, in even a small quantity, it acts so furiously on the throat and stomach as to cause intolerable agony and speedy death. Watery diluents, mixed with chalk or magnesia, are the readiest antidotes. At a temperature of about 600** F., or a few de- grees below the melting point of lead, it boils and distils over like water. This is the best method of procuring sulphuric acid free from the saline and metallic matters with which it is sometimes contaminated. The afl5nity of sulphuric acid for water is so strong, that when exposed in an open saucer, it imbibes one-third of its weight from the atmosphere in 24 hours, and fully six times its weight in a few months. Hence it should be kept excluded from the air. If four parts, by weight, of the strongest acid be suddenly mixed with one part of water, both being at 50** F., the temperature of the mixture will rise to 300**; while, on the other hand, if four parts of ice be mixed with one of sulphuric acid, they immediately liquefy and sink the thermometer to 4° below zero. From the great attraction existing between this acid and water, a saucer of it is employed to effect the rapid condensation of aqueous vapor as it exhales from a cup of water placed over it ; both standing under the exhausted receiver of an air-pump. By the cold produced by this unchecked evapo- ration in vacuo, the water is speedily frozen. To determine the purity of sulphuric acid, let it be slowly heated to the boiling point of water, and if any volatile acid matter be present, it will evaporate, with its character- istic smell. The presence of saline impurity, which is the common one, is discovered by evaporating a given weight of it in a small capsule of platinum placed on red-hot cinders. If more than two grains remain out of 500, the acid may be reckoned to be \ 798 SULPHURIC ACID. 'I 1 impure. The best test for sulphuric acid, and the soluble salts into which it cnten, Ji the nitrate of baryta, of which 182 parts are equivalent to 49 of the strongest liquid acid, or to 40 of the dry, as it exists in crystallized sulphate of potassa. Oiie twenty thou- sandth part of a grain of the acid may be detected by the grayish-white cloud which baryta forms with it. 100 parts of the concentrated acid are neutralized by 143 parts of dry carbonate of potassa, and by 1 10 of dry carbonate of soda, both perfectly pure. Of all the acids, the sulphuric is most extensively used in the arts, and is, in fact, the primary agent for obtaining almost all the others, by disengaging them from their saline combinations. In this way, nitric, muriatic, tartaric, acetic, and many other acids, are procured. It is employed in the direct formation of alum, of the sulphates of copper, zinc, potassa, soda; in that of sulphuric ether, of sugar by the saccharification of starch, and in the preparation of phosphorus, &c. It serves also for opening the pores of skins in tanning, for clearing the surfaces of metals, for determining the nature of several salts by the acid characters that are disengaged, &c. Acconling to the analysis of Dr. Thomson, the crystalline compound deposited occa- sionally in the leaden chambers above described consists of Sulphurous acid, 0*6387, or 3 atoms. Water - - 0'073?, or 1 atom. Sulphuric acid, 0-5290 2 Sulphate of lead, 00140.' Nitric acid - 0-3450 1 atom. He admits that the proportion of water is a little uncertain ; and that the prese&oe of sulphurous acid was not proved by direct analysis. When heated with water, the crys- talline matter disengages nitrous gas in abundance ; lets fall some sulphate of lead ; and the liquid is found to be sulphuric acid. When heated without water, it is decomposed with emission of nitrous gas and fuming nitric acid ; leaving a liquid which, mixed with water, produces a brisk effervescence, consisting chipfly of nitrous gas. A valuable improvement of the process for manufacturing this fundamental chemical agent has been contrived by M. Gay Lussac, and made the subject of a patent in this country by his agent M. Sautter. It consists in causing the waste gas of the vitriol chamber to ascend through the chemical cascade of M. Clement Desormes, and to en- counter there a stream of sulphuric acid of specific gravity 1-760. The nitrous acid gas, which is in a well regulated chamber always slightly redundant, is perfectly ab- sorbed by the said sulphuric acid ; which, thus impregnated, is made to trickle down through another cascade, up through which passes a current of sulphurous acid, from the combustion of sulphur in a little adjoining chamber. The condensed nitrous acid gas is thereby immediately transformed into nitrous gas (deutoxide of azote), which is transmitted from this second cascade into the large vitriol chamber, and there exercises its well-known reaction upon its aeriform contents. The economy thus effected in the sulphuric acid manufacture is such that for 100 parts of sulphur 3 of nitrate of soda will suflSce, instead of 9 or 10 as usually consumed. Upon the formation of sulphated nitrous gas (N 0«, 8 S 0^, 2 H OX and its combina- tion with the oil of vitriol, the manufacture of hydrated sulphuric acid is founded. Either sulphur is burned in mixture with about one-ninth of saltpetre : whence along with sulphuric acid gas, nitrous oxide gas is disengaged, while sulphate of potash re- mains ; thus K 0, N 0« + S — S 03 -f- N O", K O. 2. Or, nitric acid in the fluid or vaporous form may be present in the lead-chamber, into which the sulphurous acid gas passes, m consequence of placing in the flames of the sulphur a pan charged with a mixture of sulphuric acid and nitre, or nitrate of soda. This nitric acid being decomposed by a portion of the sulphurous acid, there will result sulphuric acid and nitrous gas. By the mutual re-action of the sulphurous and nitric acids, sulphuric acid and nitrous gas will be produced ; N O'* -f- 3 S — N 0' -j- 3 S O-"'. 3. Or, by heating sugar or starch with nitric acid, the mixture of nitrous gas and nitrous acid vapor which results may be thrown into the chamber among the sulphurous acid. In any one of these three cases, sulphurous acid gas, nitrous acid vapors (pro- ceeding from the mixture of nitrous oxide and atmospherical oxygen) and steam are mingled together; whence arises the crystalline compound of sulphated nitrous oxide w-ith sulphuric acid, which compound subsides in white clouds to the bottom of the chamber, and dissolves in the dilute oil of vitriol placed there, into sulphuric acid, with disengagement of nitrous gas. This gas now forms, with the remaining atmo- spherical oxygen, nitrous acid vapors once more, which condense a fresh portion of sulphurous acid gas into the above crystalline compound; and thus in perpetual al- Sulphurous acid gas does not act upon nitrous gas, not even upon the nitrous acid yapor produced by the admission of oxygen, if water be absent; but the moment that a little steam is admitted the crystalline compound is condensed. The presence of ^ SULPHURIC ACID. 799 much sulphuric acid favors the formation of the sulphated nitrous gas. These crystal. rvJinTr''. I k'P'^ ^^^"^^ ^'^^ disengagement of nitrous ga^s, which sei^ S^ oxygen present and becomes nitrous acid (hyponitric of many chemists). acid ?n^hT Sl^Mn«f ^^°^ .'u'^^'^wu^*'^ "^^H^ «^«°^* ^« condense their waste muriatic J^Pcrh f in r ' ^""^ r" u '^^^ "S^^° '"^""° ^ ^^« nuisance-creating system if they might In time, no doubt, the copper smelter will also be compelled to arrest the poisonous fumes now so wantonly evolved ; and then he too will G a profiTin that which, at present, only injures his neighbor. It is with individual intereste as wiS physical bodies, the largest are the most difficult to move from any estabHshed tS^iuia l^oL"-'a{/TH"^"H""-''!f P^""r?^ "?^^ ^° '"^^ country wL made from^ul^^^^^ alone, and, although scientific men had pointed out iron p/rites as an abundant in. dipnous source for the generation of this acid, yet no attention whatever was g^^en to this seenimgly value ess information. Folly, however, achieved that which w™om could no reach ; and the infatuated cupidity of a Sicilian king compelled our manufacture™ p^ f / r'"'"^ ^""^ ^ !:^^ ^V""^ ^^ «"^«°«^' *°^ «^«k at home that which aTohiWtiy^ export duty prevented them from obtaining abroad. Their eves were at lpn£h nl.^n^ and too late, the King of Sicily saw his error; for, th^grtL exces^^^^^^^^ sulphur has since been removed, it has not only' failed to put down thT use oMrnn pyrites, but the best informed authorities are decidedly of o&nion That this Ttfpr wm furnish the essential element for the fabrication of nearly all our sulphuriracid ThlrA 11^^ however one very serious drawback to the generaf use of iron pyrtes for su^^^^^ purpose, and that is, the presence of arsenic in all the acid thus madl^ tL obSon ^.n i! -^^ Pf.!-"- *^ ^"^ '^' "^"^^'"^^ «^^"«^ of mechanical and chemical gSiS alone Wn i''"^' f'J" important manufacture from so great an obstacle. Means^have inS b«rfll'«r'^ ^''- ?'3^'^-\^ V^^ ^''""^" ^"^"^ *^« ««'^ ^f<^r the formation of the atte^ a prSirfS.^^^^^^ ^''^ the practical working of sulphuric acid well know that such XTnVwith thrdlrfr^l' ^^^ '\' ^^^^ ''"^"- '^^^'^ ^^^^ ^^ ^^^^ ^ut two mode, at all KvJn fl ^"^^' ^^l"""^ ^^'°^ ^ P^^^'^^t the volatilization of the arsenic at all, by mixing the pyrites with some suitable ingredient ere it is thrown into fh« furnace ; and the other, to remove the arsenic from the sulphurou acid Wo^e it reache! tl f^T^f ""^ condensation. The first would be the simplest plan ; b^t Tn the e^? bevotl f h""/ ''''°''f '"° ""^'"'^^ ^" *i°P^^ ^^^- The last, howeve?, is iot by any mTn^ thHrsPni K -P' ""' Pt"7«»-*°arkable success by Sir William John Newton, Knt, I have great pleasure in transferring into this Dictionary the very specific instructions which he has published 00 the subject in the first number of the " Photc^raphic Journal." To iodize the Paper. — Ist* Brush your paper over with muriate of barytes (half ain ounce, dissolved in nearly a wine-bottle of distilled water) : lay it flat to dry. 2d. Dissolve sixty grains of nitrate of silver in about an ounce of distilled water. Ditto sixty grains of iodide of potassium in another bottle with the like quantity of water. Mix them together and shake well : let it subside : pour off the water, and then add hot water : shake it well : let it subside : pour off the water, and then add three ounces of distilled water, and afterward as much iodide of potassium as will redissolve the iodido of silver. Brush your previously-prepared paper well with this, and let dry ; then place them in water, one by one, for about one hour and a half or two hours, constantly agitating the water. As many as a dozen pieces may be put into the water, one after the other, taking care that there are no air bubbles ; take them out, and pin to the edge of a board at one corner. When dry they will be ready for exciting for the camera by the following process : 1 drachm of No. 4. 6 drachms of distilled water. 4 25 grains of nitrate of sil- ver to half an ounce of water. Add 45 minims of glacial acetic acid. 2 20 min. of No. 8, 6 drachms of distilled water. 2 drachms of No. 4, 6 drs. of water. A saturated solution of gal- lic acid. Equal parts of Nos. 1 and 2. N. B. — This must be mixed just before using, and the bottle cleaned af- terward. (These are supposed to be in six 1-ounce bottles with glass stoppers.) To excite for the Camera. — Mix equal parts of Nos. 1 and 2, and with a glass rod excite the iodized paper and blot off ; and it may be put in the slide at once, or the number you require may be excited, and put into a blotting-paper book, one between each leaf, and allowed to remain until required to be placed in the slide. 2Kme of Expomre. — ^The time varies from three minutes to a quarter of an hour, according to the nature of the subject and the power of the sun ; out five minutes is generally the proper time. To bring out. — ^Bring out with No. 8, and when the subject begins to appear, add Na 5 ; and when sufficiently developed hold it up, and pour water upon it ; and then put it into hyposulphite of soda to nx it, for about half an hour or more, and then into water : this is merely to fix it for the after process at your leisure. To clean the Negative. — Get a zinc tray about three or four inches deep, with another tray to fit in at the top, about one inch deep ; fill the lower tray with boiling water, so that the upper tray may touch the water ; put your solution of hyposulphite of soda, not strong in the upper tray, and then your negatives one by one, watching them with care until the iodine is removed ; then put them in hot water, containing a small piece of common soda (the size of a nutmeg to about two quarts of waterl for about ten minutes; pour off the dirty water, and then add more hot water, shaking them gently for a short time; pour off the water again, and then add fresh hot water, and let it re- main until it is cold, after which take them out carefully one by one, and put them in clean cold water for an hour or two; then take them all out together, and hold np to drain for a short time, and then put them between three or four thicknesses of linei^ and press as much of the water out as you can ; then carefully (for now all the sizo is removed) lay them out flat separately upon linen to dry. SUN PAINTING. 803 Mode of Waxing the Negative*, — Melt the pure white wax over a lamp of moderate heat, just merely^ to keep it in a liquid state ; then fill the same deep tray as above de- scribed with boiling water, and with another similar to the upper one before described (which must be kept for this purpose only) ; put a clean piece of blotting-paper in this tray, and lay your negative face downwards, and with a soft flat hog's hair-brush, about an inch wide, dip it into the liquid wax, and brush the negative over, when it will be immediately transparent, and it can be done so that there is very little redundant wax, after which it may be put between two or three thicknesses of blotting-paper and ironed, if necessary, which should not be very hot, when it is ready to take positives from. Positives on Negative Paper. — ^Take one part of the iodide of silver before described and add two parts of water ; then add as much iodide of potassium as will redissolre it Brush your paper with the foregoing, let dry, put into water, and proceed in all re- spects, as above described for the negatives. Excite for positives. — Excite with No. 1; blot off; lay it in your press, place the negative face downwards ; expose to the light from ten seconds to half a minute, or more according to the light (not in the sun), and bring out with No. 3 ; and when it is nearly developed add No. 1 ; then take it up and pour water upon it, and then place it in hyposulphite of soda (cold) until the iodide is removed ; after which put it into alum water, about half a teaspoonful of powdered alum in two quarts of water ; this will readily remove the hyposulphite, and also fix the positive more particularly ; it will also take away any impurities which there may be in the paper, alter which put it into clean cold water, and change two or three times. I have been thus particular in describing the process which I have adopted, more especially for beginners ; and with great cleanliness and care in each process, and especially in keeping all the bottles with the chemicals free from dirt of every kind, the foregoing will lead to favorable results. Motive for washing the paper over with chloride of barium previous to iodizing. — In the first place, I find that it appears to give strength to the paper. Secondly, that the action in the camera is better and more certain. Thirdly, it keeps cleaner in the bringing-out process, thereby allowing a longer time for a more complete development. Fourthly, I have never found any solarizing take place since I have used it (about three years) ; and, fifthly, I find that it keeps longer and better after it is excited for the eamera. From the observations which I have made since I have made use of chloride of bari- um, I conclude that it has the effect of destroying any injurious properties which may be in the paper, and more especially with respect to the size ; and besides which, when combined with iodide of silver, greater intensity is obtained in the negative. I have occasionally prepared paper without chloride of barium, but I have always found (except for positives) that I could not rely upon it with the same degree of cer- tainty. I need scarcely add that throughout the whole of this process the greatest care and attention are required, and that the water should be constantly agitated while the paper is in it, and that the water should be once changed. Rationale of the action of the common soda and powdered alum^ dsc. — ^My motive for nsing common soda to cleanse the negatives is, that it not only removes tiie hypo- sulphite of soda more readily, but any impurities which may be in the paper, as well as the whole of the size, such being absolutely necessary for the after waxing process ; which, when done, the negative should appear nearly as transparent as glass. Tho reason why I prefer alum for the positives is, that while it has the effect of re- moving the hyposulphite (A soda and other impurities in the paper, it does not act upon the size, which in this instance it is desirous to retain. I have been induced to make a series of experiments, with a view to prevent the fading of the positives, or, indeed, that any portion should be, as it were eaten away in parts; and since I have adopted the foregoing in no one instance has any change tAcen place whatever. — Sir W. J. Newton. Mr. Fenton, one of the most expert and successful heliographers, recommends for pi^r to be used the same day that it is excited, two grammes of common salt to be added to the iodizing solution. This addition increased the rapidity of the formation of the picture, but much lessened the time during which the paper could be kept in a sensitive state uninjured. The solution for exciting the paper was the usual one of SO grammes of nitrate of silver, and half a drachm of acetic acid to the ounce of water. The paper on which the greater part of Mr. Fenton's negatives were taken was iodized by the following preparation : — Rice water - - - . looo gramme* Iodide of potassium . . SO Bromide of potassium - - 8 Cvanide of potassium - - 2 Fluoride of potassium - • li I 804 SYRUP. An even film of collodion may be obtained by the following means. Represent tlie plate of glass by the following figure : — Hold the plate with the left hand at 1, pour a body of collodion in the centre, tilt towards 1 (being careful not to let it touch the thumb), incline towards 2, run into 8, and pour oflf at 4. Then hold the plate vertically (resting the corner 4 on the neck of the collodion bottle) to drain ; incline it first to the right and then to the left^ repeating this several times until the ridges are removed. By these means an even film may be produced without a thick ridge from 2 to 4. The time it may be left without plunging into the silver bath will depend upon the temperature (about half a minute). Dip evenly into the bath, lifting up and down to allow the evaporation of the ether; the film will also saturate more rapidly. When the greasy appearance is gone, it is ready for the camera. Sometimes the film is nearly transparent and bluish, not having suf- ficient iodide of silver ; or it may contain too much iodide, the greater part flaking oflf in the bath, leaving the collodion with very little, and that patchy ; or from being placed in the bath too quick, the lower corner will present a reticulated appearance, which of course renders it useless. Having exposed the plate the necessary time, the next step is the development The solution employed by some is prepared with protosulphate of iron. The proportions are,— "Water Acetic acid {Beaufoy'i) Protosulphate of iron Nitric acid - 2 oz^ - 1 drachm - 8 grains - 2 drops. Mix the water and acetic acid first ; then dissolve the sulphate of iron, and, lastly, add the nitric acid, which, by varying the quantity, produces different effects. On pouring the solution over the plate, there is sometimes a difficulty experienced in causing it to flow evenly. Sometimes a little more acetic acid in the developing solution, or, if the plate has been out of the bath for some time, redipping it, will prevent this ; but if this does not remove it, and the resulting picture is hard and unpleasant in tone, anew bath is necessary. For positives the resulting picture is more pleasing and delicate, by using the developing agent rather weak. After it has remained on sufficiently long to bring out the image, the undecompounded iodide is to be removed by hyposulphate of soda. SUSPENSION BRIDGES. Suspension bridges of iron were introduced about the year 1741, at which date one of 70 feet span was thrown over the river Tees. Sca- mozzi, Del Idea Archi, published 1615, conveys some notion of these structures; but Bernouilli first explained their true principles. The Union bridge over the Tweed 449 feet span, constructed by Captain Sir S. Brown, in 1820, was the first large bar chain bridge erected in Britain. The Newhaven and Brighton suspension piers were also erected by the same engineer. The great bridge by Telford, across the Menai Straits, is 670 feet span; it was commenced in May, 1819, and completed in December, 1826. The Hammersmith bridge, 422 feet span, by Tierney Clark, was completed in 1824. The Montrose bridge, by Rendel, 412 feet span, was erected in 1829 ; and the Hunger- ford bridge over the Thames, 67 6i feet span, by Brunei, was built in 1844. The wire- rope bridge of Freiburg is 820 feet span. The road-ways of suspension bridges must not merely be hung from the chains, but be rendered stiff, to resist the undulatory mo- tion caused by the wind. See Minutes of Proceedings of the Institution of Civil Engi- neers, Feb. 16, 1841, on this subject SWEEP- WASHER, is the person who extracts from the sweeping, potsherds, Ac, of refineries of silver and gold, the small residuum of precious metal. SYNTHESIS, is a Greek word, which signifies combination, and is applied to the chemical action which unites dissimilar bodies into a uniform compound ; as sulphurio acid and lime into gypsum ; or chlorine and sodium into culinary salt SYRUP, is a solution of sugar in water. Cane-juice, concentrated to a density of 1*800, forms a syrup which does not ferment in the transport home from the West Indies, and may be boiled and refined at one step into superior sugar-loaves, with emi- nent advantage to the planter, the refiner, and the revenue. Syrup, juration of, through beds of bone black, has been prescribed as follows by Messrs Greenwood and Parker. Suppose 5 filter beds, Nos. 1, 2, 8, 4, 5, to be in action, TANNIN, PREPARATION OF. 805 of which Na 1 has been longest in use ; No. 2 the next longest, and so on. As soon as No. 1 has become too impure to be used any longer, it is thrown out of action, No. 2 becomes the first of the series, and No. 6 is brought into use as the last of the seriea The process of filtration goes on until No. 2 becomes too impure to be longer employed ; it is then thrown out of action, and No. 3 becomes the first in the series; and No. 1 (which has been supplied with fresh filtering materials in the meanwhile) is brought into use as the last of the series. The several filter beds are connected together by pipes (provided with stopcocks), in such a manner that the filtered syrup will pass from the lower part of No. 1 into the upper part of Na 2, and from the lower part of No. 2 into the upper part of No. 3, and so on. T. TABBYING, or WATERING, is the process of giving stuffs a wavy appearance with the calender. TACAMAHAC is a resin obtained from the Fagura octandra, a tree which grows in Mexico and the West Indies. It occurs in yellowish pieces, of a strong smell, and a bitterish aromatic taste. That from the island of Madagascar has a greenish tint. TAFFETA is a light silk fabric, with a considerable lustre or gloss. TAFIA is a variety of rum. TALC is a mineral genus, which is divided into two species, the common and the indurated. The first occurs massive, disseminated in plates, imitative, or crystallized in small six-sided tables. It is splendent, pearly, or semi-metallic, translucent, flexible, but not elastic. It yields to the nail ; spec. grav. 2*77. Before the blowpipe, it first whitens and then fuses into an enamel globule. It consists of— silica, 62 ; magnesia, 27 ; alu- mina, 1'5; oxyde of iron, 3*5; water, 6. Klaproth found 2| per cent, of potash in it. It is found in beds of clay-slate and mica slate, in Aberdeenshire, Banffshire, Perthshire, Salzburg, the Tyrol, and St. Gothard. It is an ingredient in rouge for the toilette, com> municating softness to the skin. It gives the flesh polish to soft alabaster figures, and is also used in porcelain paste. The second species, or talc-slate, has a greenish-gray color ; is massive, with tabular fragments, translucent on the edges, soft, with a white streak ; easily cut or broken, but is not flexible ; and has a greasy feel. It occurs in the same localities as the preceding. It is employed in the porcelain and crayon manufactures ; as also as a crayon itself, by carpenters, tailors, and glaziers. TALLOW (Suify Fr. ; Talgj Germ.) is the concrete fat of quadrupeds and man. That of the ox consists of 76 parts of stearine, and 24 of oleine; that of the sheep contains somewhat more stearine. See Fat and Stearine. Tallow imported into the United Kingdom, in 1836, 1,186,364 cwts. 1 qr. 4 lbs.; m 1837, 1,308,734 cwts. 1 qr. 4 lbs. Retained for home consumption, in 1836, 1,318,678 cwts. 1 qr. 25 lbs. ; in 1837, 1,294,009 cwts. 2 qrs. 21 lbs. Duty received, in 1836, £208,284 ; in 1837, £204,377. TALLOW, PINEY. See Piney Tallow. TAMPING is a term used by miners to express the filling up of the hole which they have bored in a rock, for the purpose of blasting it with gunpowder. See Mines. TAN, or TANNIC ACID. (Tannin^ Fr. ; Gerbstoff, (Germ.) See its preparation and properties described under Galls. The barks replete with this principle should be stripped with hatchets and bills, from the trunk and branches of trees, not less than 30 years of age, in sprine, when their sap flows most freely. Trees are also sometimes barked in autumn, and left standing, whereby they cease to vegetate, and perish ere long ; but afford, it is thought, a more compact timber. This operation is, however, too troublesome to be generally practised, and therefore the bark is commonly obtained from felled trees ; and it is richer in tannia Ibe older they are. The bark mill is described in Gregory's Mechanics, and other similai Vorks. TANNIN, PREPARATION OF. The substance from which tannin is most fre- ?uently obtained is nutgalls, of which it constitutes about 40 per cent of their weight t may be procured also from several other sources, such as oak, horse chestnut, sumach, and cinchona barks, catechu, kino, ^'^^ ''S^^'' ^ ^*^ l»appened in tlie portion touching the basin itself. TANNING (banner, Fr.; G drberei, Germ.) is the art of converting skin into Lkathkr which see. It has been ascertained, beyond a doubt, that " the saturated infusions of astringent harks contain much less extractive matter, in proportion to their tannin, than the weak infusions; and when skin is quickly tanned (in the former), cowmon expe- nence shows that it produces leather less durable than leather slowly formed."* The older tanners who prided themselves on producing a substantial article, were so much impressed with the advantages of slowly impre-natin? skin with astringent matter, that they employed no concentrated infusion (ooze) in their pits, but stratified the skins with abundance of ground bark, and covered them with soft water, knowing that its active principles are very soluble, and that, by being gradually extracted, they would penetrate uniformly the whole of the animal fibres, instead of acting chiefly upon the surface, and making brittle leather, as the strong infusions never fail to do. In fact, 100 pounds of «kin, quickly tanned in a strong infusion of bark, produce 137 of leather • while 100 pounds, slowly tanned in a weak infusion, produce only 1 17|. The additional'l9* pounds weight in the former case serve merely to swell the tanner's bill, while they deteriorate his leather, and cause it to contain much less of the textile animal solid. Leather thu« highly charged with tannin is, moreover, so spongy as to allow moisture to pass readilr through Its pores, to the great discomfort and danger of persons who wear shoes made uT -^^^ ^^^*"" of time, and the increase of product, are temptations strong enough to induce many modern tanners to steep their skins in a succession of stron- irJ fusions of bark, is sufficiently intelligible; but that any shoemaker should he so i?nomnl or so foolish as to proclaim that his leather is made by a process so injurious to its quality, is unaccountably stupid. j "u. lo w TANTALUM is the rare metal, also called Columbium. TAPESTRY is an ornamental figured textile fabric of worsted or silk, for lining the walls of apartments ; of which the most famous is that of the Gobelins Royal Manufao- iory) iiccLr i siris* TAPESTRY AND LACE. Some of the objects included in this claes in the Exhi- bition presented, from their remarkable disposition in the building, a highly attractive and interesting appearance, suspended from the girders over the galleries, and thus dis- played to the best advantage, and under circumstances the most highly calculated to develop their peculiar beauties; the specimens of carpets, oil-cloths, and tapestry, must be considered as having occupied a very prominent space in the Exhibition^ The following sub-classes had a place under the general classes, inclusive of these and other articles : A, tapestry, as carpets of all kinds, Axminster, Brussels, Kidderminster, &c, matting, oi -cloth, counterpanes, and ornamental tapestry of different materials; B lace as pillow- ace, made wholly by hand, and machine-wrought lace; C, sewed and temboured muslins ; D, embroidery by hand and machinery, and in different materials; £, fringes, tassels, ^ contain extensive factories solely engaged in the production of the various descriptions of carpets in ordinary domestic use. The application of the power-loom to the carpet manufacture is recent, and its use is extending. A great variety of combina- tion of materials was exhibited, many of which indicated a remarkable departure from the ordinary method of manufacturing carpets and similar objects. One of these was a species of mosaic tapestry, where the cut wool was fixed to a ground or foundation of caoutchouc. ° The lace productions of Honiton and Buckinghamshire have long attained universal renown. These laces are chiefly wrought by hand at the houses of the persons concerned in their manufacture ; but recently a combination of machine-made lace and pillow-made * Sir H. Davy, on the Operation of Aatringent Vegetables in Tanning.-PAiZ. Trans. 1803. TAR (COAL). 809 (jmament has been introduced, under the title of "appliqu^e lace." The machine lace of Nottingham has scarcely an inferior degree of celebrity : in that town factories are in almost constant work, producing by the aid of a large number of the most delicate and costly automatic engines this splendid fabric. In a preceding class these machines were described, and were exhibited in motion in another part of the building. In the south central gallery were some beautiful specimens of the intricate and elegant orna- mentation capable of being imparted by these machines. Of the lace made bv hand various interesting specimens were shown, which represented much patient e&brt in the instruction of the poor in this art and considerable taste in design. Few departments of ornamental industry have experienced so many vicissitudes, in consequence of the introduction of mechanical power, as that of the lace manufacture. The lace of Honiton in Devon has long rivalled the most beautiful and costly produc- tions of the continent At one period during the last war, veils of Honiton lace sold for very large sums, as much as 100 guineas having been paid for fine specimens: Honiton lace is entirely made on the pillow by hand labor. ^^ The application of machinery to the production of lace is very remarkable and interesting, as probably few introductions of machinery to textile manufactures pro- duced so sudden an alteration on the expiration of the patent protecting it, in the or- dinary course of fabrication. The bobbin-net machine was invented in 1809; it came into general use in 1823, and an immense stimulus was communicated to the manufacture. The power of production of this machine are to hand labor nearly as 80,000 to 6, and the lace production by it has, in plain articles, wholly superseded that made by hand. See Bobbinet. TAPIOCA, is a modification of starch, partially converted into gum, by heating and stirring cassava upon iron platea See Cassava andi Starch. TAR of ioood{Goitdron.; Fr. ; Ther, Germ.); is the viscid, brown-black, resino-oleagi- nous compound, obtained by distilling wood in close vessels, or in ovens of a peculiar con- struction. See Charcoal, PrrcoAL, coking of, and Ptrolignous Acid. According to Reichenbach, tar contains the peculiar proximate principles, parajine, eupion, creosote^ picamar, pittacall, besides pyrogenous resin, or pi/retine, pryogenous oil, or pyroleiiie, and yinegar. The resin, oil, and vinegar are called empyreumatic, in common language. TAR (COAL). There is not perhaps any waste article of our manufacturing indus- try which has been so singularly neglected as coal-tar, and yet there can be but veiy few which offer anything like so fair a field of remuneration for the exercise of skiU and ingenuity. To begin : the article has hitherto been, and still in great measure con- tinues, entirely valueless; it has in fact only a nominal price in the market, as is evi- denced by the circumstance that it is consumed as fuel at many of our large metropoli- tan gas works, and at others is sold as low as at the rate of one penny for 6 gallons. This latter is however far from its real value even as fuel, for it has been found in prac- tice that the average heating power of tar, as compared with coke, upon a long series of workings, is as more than two to one, or in other words that a gallon of tar weigh- ing about 10| lbs. affords as much heat as half a bushel or 22 lbs. of coke, and this too although the tar contains about one pound of water entangled in its substance or chemi- cally combined, so as not to be separable by long standing. As we have before said, the tar thus adulterated with water is still equal to more than double its weight of good coke as a heating agent, when tested upon a large working scale for many months in succession. This fact ought to convince us, if any doubt yet remains, of the folly and ig- norance of those persons who assert that the value of coal as a calorific substance de- pends solely upon the amount of carbon or coke which it contains, and is in no way proportioned to or affected by the quantity of its tarry or volatile products. The truth would appear to be, that where a coal affords by distillation 30 per cent of these tarry products, its heating power is exactly double of that which the residuary carbon or coke 18 able to produce ; and this proportion of volatile to fixed matter is just about the ratio existing in most bituminous coals, so that^ as a general rule, the advocates of the above hypothesis are wrong to the extent of one half. The high heating power of coal-tar ought to induce the managers of gas works either to use it themselves, or, where this cannot be done, to vend it at a price proportioned to its value in coke ; thus, presuming a bushel of coke to be worth 4 Acid eas is diseneaeed. Potash. * * A preeipitote soluble in The a great excess of pre- cipitont. A white preeipitote, soluble in excess. A white preeipitote, slightly soluble in a great excess. A white precipitate, slightly soluble in a great excess. A white precipi tot , slightly soluble in ex- A green preeipitote, insoluble in excess, turning brown at the Mirfisoe. The same. A permanent white precipitate. sHghtly soluble in Muriate of Ammonia. A brown voluminous preeipitote. A white precipitate, insoluble in excess, but soluble in Muriate of Ammonia or Caus- tic Alkalies. A red preeipitote which boiling renders blue A lighter green preeipi- tote. The The same ; completely soluble m a great ex cess. nnlMiveiy A white preeipitote, soluble in Muriate of Ammooia. A lighter brown preei- pitote. The same. The The sanu dilute. The A white preeipitote which behaves m thft same manner. A red preeipitote. The same ^ Carbonic Acid gas u given oS. The The same ; Carbonia Acid is disengaged [821] ANALYTICAL CHEMISTRY PESTALOZZIAN INSTITUTION, WORKSOP, BY JAMES HAYWOOD. Eeagents in the horizontal, arc generally of so characteristic a nature as not to be mistalcen by the youngest Assistant to the proficient in Chemistry in conducting an analysis, or in general experimental researcn. CARBONATE OF AMMQNIA. SULPHURETTED HYDROGEN. No preeipitote. The HUM. The The Same at the Bicarbonate of Potash, soluble in Muriate of Ammonia. The tame. A white preeipitote, sol- able in excess. The The same. The same; more easily soluble in excess. Thesama. TheaaoM. The same. A white preeipitote, sol- uble in excess. No preeipitote. No precipitate. No preeipitote. No precipitate. HYDROSULPHATE OF AMMONIA. YELLOW PRUSSIATE RED PRUSSIATE OF OF POTASH. i POTASH. No preeipitote in any solution. No preeipitote. No preeipitote. No preeipitote. No preeipitote. No preeipitote. No preeipitote nnless Ammonia l>e added. A milk-white preeipitote of Sulphur ; solution then contoins a Frote- salt. No preeipitote if the test is pure. A white preeipitote of Alumina, soluble in Potash. A white preeipitote, sol- uble in PotasD. A white predpitote of Thorina. A preeipitote of Yttria. No preeipitote. No precipitate. A white heavy preeipi- tote, soluble m acids. A white preeipitote. No precipitate. A voluminous preeipitote. A white preeipitote. A white preeipitote of Protoxide. A flesh-red preeipitote, turning brownish in contoct with the air. The flesh-red preeipi- tote — the preeipitote by Ammonia is turned flesh-red by it. A white preeipitote if A white preeipitote, in- neutral, but none if soluble m excess, acid. A red preeipitote, solu- No preeipitote ; solution ble in Muriate of Am- turns darker. A green precipitate, sol- uble in excess, forming a bluish solution. Thesame. A light brown preeipi- tote. No preeipitote ; solution turns darker. No preeipitote. A milk-white preeipitote of Sulphur; solution then contains Protoxide, A black precipitate, in- soluble m excess. A black preeipitote and color, slightly soluble in excess. A black precipitate, turn- ing brown at the surface. A black preeipitote — same as tae Protoxide. A white preeipitote. A pale red preeipitote, soluble in uee acida. A grayish green preei- pitote. A gelatinous white pre- eipitote, insoluble in Muriatic Acid. A green preeipitote, turning gray, insoluble in Muriatic Acid. A white preeipitote — tilightly tending to green, insoluble in Mu- riatic Acid. A light blue preeipitote, turning darlcer, insolu- ble in Muriatic Acid. An immediate dark blue Srecipitote, insoluble in luriatie Acid. No precipitate. No preeipitote. No precipitate. No precipitate. A brown preeipitote, in- soluble m free acida. The same as tlie Protox- ide. A yellowish red predpi- tote, soluble in Muria- tic Acid. A reddish brown pred- Sitote, insoluble in luriatie Acid. A yellowish green pre- cipitate, insoluble in Munatic Acid. An immediate dark bln« preeipitote, insolnble m acids. No preeipitote. 822] A TABLE OF ANALYTICAL CHEMISTRY— Continued. [823 SALTS OF POTASH •• SODA UTHIA . BARYTA. STRONTLA LUIE liAGNESU . ALUMINA GLUCINA THORINA YTTRIA . ZIRCONIA • • • CKRIUM . j PROTOXIDE 1 PEROXIDE MANGAXESE, PROTOXIDE . (SESQUIOXIDE MANGANESE ■{ and ( PEROXIDE ZINC. COBALT mCKEL (PROTOXIDE -{ and I PEROXIDE (PROTOXIDE < and ( PEROXIDE IRON, PROTOXIDE IRON i (SKSQUIXODE < and (PEROXIDE OXALIC ACED. No preeipiUta. No precipitate unlet left for some day«. A troubling in strong •olutiona; if Ammo- nia be added a pre- cipitate. An immediate preci- pitate, soluble m Ni- tric or Muriatic Acid. No precipitAt« unleM Ammonia be added. No precipitate. No precipitate. A white precipitate, ioaoluble in exceu. A white precipitate, soluble in Muriatic Acid. A white precipitate, soluble m a great excess or in Muriatic Acid. A white precipitate, even in acid solu- tions, sparingly solu- ble in Muriatic Acid. A white crystallme deposit, onlesa very dilute. 'So precipitate, bat the solution is soon rendered colorless. A white precipitate, soluble in free Acids and Alkalies. A slight troubling and shortly a pale red precipitate. No immediate precipi- tate, but a slow de- posit. A yellow color, and shortly a precipitate. No precipitate ; solu- tion turns yellowish. IODIDE OF POTASSIUM. SULPHATR OF POTASH. PHOSPHATE OF SODA. No precipitate. No precipitate. No precipitate. A white precipitate, if Ammonia be add- A voluminous white precipitate, insoluble in strong acids. The same as Baryta ; rather more soluble in water. No precipitate in di- lute solutions, but a white one if strong. No precipitate. After a time Crystals of Alum are formed. No precipitate ; but if Aiuinonia be added, a strong one. A white precipitate, aoluble in free acids. Same as Baryta. Same aa Baryta. A white precipitate, particularly if Am- monia be added. A white precipitate, soluble in Acids or Potash. No erystala are formed. A voluminoua precipi- tate. Thrown down aa a double salt, insoluble in excess. After a time a precipi- tate is formed, but is easily soluble is an excess. A white precipitate, almost insoluble in water and acids. After a time a precipi- tate insoluble in ex- cess. No precipitate. No precipitato. No precipitate. No precipitate. No precipitate. A white flaky precipi- tate. A white precipitate, soluble in acids, but is Again precipitated by boiling. A voluminous precipi- tate. A white precipitate. A permanent white precipitate. A brown precipitate in neutral solutions. A white precipitate, soluble in free Acids and Alkalies. A blue precipitate. A white precipitate, slightly tendmg to green. A white precipitate, turning green. A white precipitate, which Ammonia tnrnH brown, and at length dissolves. .^p BEFORE THE BLOWPIPE. Ko pndpitaU, OBSERVATIONS. On Platinnm wire tinges outer flame violet : with Borax and Oxide of Nickel, a blue l>ead. The bead of Nickel and Borax is not changed by Soda; heated on Pla- tinum wire tinges outer flame yel- k)w. Tinges outer flame of a carmine color ; the double phosphate is fusible. Cannot easily be distinguished ; the Chloride tinges outer flame green- ish; infusible alone; fusible with flaxes. Tinges outer flame carmine red when heated on Platinum wire. Same as Strontia, only not so bright ; gives a powerful white light when strongly heated. When ft Salt of Magnesia that hae been heated, is moistened with Nitrate of Cobalt, it acquires a pale red color. Treated as the above on Charcoal, a fine blue color is communicated to the assay. Gives a white precipitate with Tartanc Acd, a yeUowow with Chloride of Pfatinum, and a golatmous one ^^J^»y^ fluosilicic Acid, which distinguishes it from other subetancea. Gives no precipitate with Tartaric Acid, or Chbride of Flftti- nam, by which it may be diitingiufthed. No precipitate with Chloride of Plfttinwn ; can ea«ly be di»- tinguished firom the former. Easily distinguished by forminje • white precipiute with Sulphates LxA Carbonates. The Chloride is msoluUe u» AlcohoL Distinguished from Baryta by giving a precipitate yi}l« Hydro- fluosnicic Acid, and by the filtered liquid of the still Alkaline Sulphate giving a precipiUte with BaryU water. DlBtiniruiBhed from Baryta and Strontia by giving no prwdpi tate with Sulphates when diluted, separated m the sUte ot Nitrates and Chlorides by AlcohoL EasUy distinguished and separated by Sulphates from the above, or by the precipiUtes being all soluble m MunaU of Ammonia. Distinguished f^m the Alkalis by givme a white precipiUte with Ammonia, and may be separated from most other sub- stances by Caustic Potash. When moistened with Nitrate of Co- balt, becomes dark gray, or nearly bladL. Not easily distinguished ; produces a colorless bead with Borax. Yttria behaves in the same manner MGlncina. Cannot easily be distingoished from similar substances. Converted to peroxide, soluble m Borax, producing a red bead, color flies on cooling. Produces a bead of an amethyst col- or in the outer flame with Borax, which disappears in the inner flame. Same as Protoxide. On Charcoal with Soda a coat of white Oxide is formed; with Ni- trate of Cobalt they aaeume a green color. The smallest portion colors Borax strongly blue ; reduced to a metallic aUte with Soda; magnetic With Borax in the outer flame, a reddish color, which disappeara when cold ; with Soda, a white magnetic powder. With Borax in the outer flame, a red bead, turning lighter as it cools; mterior flame a green bead, turning lighter on cooling. Peroxide behaves b the same man- ner ; with Soda, a magnetic powder is obtained. Maybe distinguUhed from Alumina by the Cwbonates, from aiagnesia by being insoluble in Muriate of Ammonia, ana from Lime and the Alkalis by Ammonia. Thorina may be distinguished and senarated from the abovjs substances, as it is perfecUy insoluble alter igmUon m all acids except the Sulphuric Distinguished from Thorina by Sulphate of Potash, and f^m the other suUtanoes described by the same means as Thorma. Distinguished from Thorma by Sulphate of Potash and Oxalic Acidfand from Yttria by its Oxide, after igmUon, bemg insol- table in all Acids, except the Sulphuric Distinguished from other substances previoosly described by tummg into a red Peroxide when heated m contact ^ith the atmosphere. The reaction of these salU with Hydroaulphate of Ammonia is to well chaiacterixed that they cannot be mistaken. The Peroxide is alwavs converted into the Deutoxide by solo- tion in an Acid. MuriaUc Acid converU it mto Protoxide by boiling. The solution in Potash is precipitated by Hyd. Sal. Am. which distinguishes it from earthy salts, and may easUy be lep^ rated from other metals by Ammonia. Easily distinguUhed from all other salU by their behavior wiu Hydroeolphate of Ammo nia. Distinguished from Cobalt by Ammonia and Potash, and from other subetanoes in the aame way aa Cobalt. The Salta of Iron are easily distinguished ^J *«^^^^ with the Prussiates ; may be separated from Manganese by Succinate of Soda. Peroxide if distinguished and separated from Protoxide by Red Pmssiate of Potash and Ammonia. 824] A TABLE OF ANALYTICAL CHEMISTEY— CoNTnnjED. [825 i CADMIUM LEAD BISMUTH j PROTOXIDE ( PEROXIDE COPPER, DEUTOXIDE . SlliV EIR « • • • MERCURY, PROTOXIDE MERCURY, PEROXIDE PLATDTA GOLD . . TXN.PROTOXTOE TIN, PEROXIDB ANTIMONY . CHROMIUM . TANADIUM . COLUMBIUM . IRIDIUM. . RHODIUM . PALLADIUM . OSMIUM . TELLURIUM . TTIAimTM . TUNGSTEN . URANIUM . MOLYBDENUM AMMONIA. A white preeipitAt«, •olubl« m ft slight ezceu. A white precipitate, inaoluble in an ez- cesa, except with the Acetate. A white precipitate, inaoluble in excess. A green precipitate, and deep purple solu- tion ; again precipitat- ed by Potash if boiled. A brown precipitate, ▼ery soluble in ex- cess, but is repreci- pitated by Potash. A black precipitate, insoluble in excess. A white precipitate, insoluble in an excess. A yellow precipitate, soluble in excess, in- soluble m free acids. A yellow precipitate. A white precipitate, insoluble in excess. A white precipitate, soluble in acids and in an excess. A white precipitate insoluble in excess and in Muriatic Acid. A ^eenish blue preci- pitate, insoluble in excess. A grayish white pre- cipitiite, turning red and dissolving. Is readily dissolved, and may be again precipitated by acids. A brown precipitate, partly soluble, form- ing a purple solution. Shortly a lemon yel- low color. A yellowish precipi- tate, slightly soluble in excess. No precipitate; solu- tion turns yellow. A white precipitate, soluble in excess. A white precipitate, insoluble in excess. The Acid dissolves, but is again precipitated by stronger acids. A brown flaky preci- pitate, insoluble in excess. The Acid is dissolved, and the Protoxide forms a brown preci- pitate. POTASH. A white precipitate, insoluble in excess. A white precipitate, soluble in a great ex- cess. The same. A fp-een precipitate, which boiling renders black. A brown precipitate, insoluble in excess, but soluble in Am- monia. A black precipitate, soluble in an excess. A yellow or white pre- cipitate, insoluble in excess. A yellow precipitate, soluble in e xcesa when boiled ; and again pre- cipitated by acids. At first no precipitate, but shortly a black one. A white precipitate, soluble in excess ; de- composed by boiling. The same, soluble in excess. The same, soluble in Muriatic Acid. A green precipitate, sol- uble in excess ; again thrown down by boil- ing. The same. The same, insoluble in strong acids. A dark brown preci- pitate. A yellow precipitate, soluble in acids. An orange colored pre- cipitate from the Ni- trate. Fused with it, the whole is soluble in water. A white precipitate, soluble m excess ; re- precipitated by acids. The same. The same. A yellowish precipi- tate, insoluble in ex- cess. llie same ; precipitate insoluble m excess. CARBONATE OF POTASH. A white precipitate, insoluble m excess. A white precipitate, inaoluble in excess ; but soluble in Potash. The A green precipitate, which boiling renders black. BICARBONATE OF POTASH. soluble _ precipitate, ill Ammonia. A dirty yellow preci- pitate, which boiling renders black. A reddish brown pre- cijpitate ; if it contains Muriate of Ammonia a white one. A yellow precipitate, insoluble va excess. No precipitate. A white precipitate, insoluble in excess. The same; deposits slowly again after solution. The same. A green precipitate, slightly soluble in excess. A grayish white pre- cipitate, soluble in The same, and may be dissolved by Ace- tic Acid. No precipitate ; color destroyed. A gelatinous precipi- tate when boiled with the double Chloride. A deep brown precipi- tate, insoluble in ex- cess. No precipitate ; solu- tion turns yellowish. The same. The same. Is insoluble in water when fused with it. The same, slightly sol- uble. A brown precipitate, soluble in excess. A white precipitate. Carbonic Acid is dis- engaged. A similar precipitate, with an evolution of The same. A light green preci- pitate, soluble m an excess. The same. A white precipitate, rendered black by boiling. A reddish brown pre- cipitate, either imme- diate or after a time. The same ; Muriatic Acid must be added in all cases. No precipitate. The same. A white precipitate, insoluble ia excess. The same. The same ; rather lighter. The same. The same. The same. No precipiteto. The same. The same. The same. The The The . CARBONATE OF AMMONIA. A white precipitate, in- solnble m excess. The same. ®"hySS^?J^^ I HTOROSULPHATE HYDROGEN. OF AMMONIA. The same. A green precipitate, sol- uble in excess, same as Ammonia. A white precipitate, sol- nble in excess. A gray or black precipi- tate. A white precipitate. A yellow precipitate. A yellow precipitate, if neutral. The same. Tbeiune. The same. A yellow precipitate. A black precipitate, in both neutral and acid solutions. A black precipiute, in both neutral and acid solutions. A black or dark brown precipitate, in both neutral and acid solu- tions. A black precipitate, in both neutral and acid solutions. A black precipitate, in acid and neutral solu- tions. A black precipitate, turn- ing white, and again black by an excess, soluble in Potash. A brown color and short- ly a precipitate. YELLOW PRUSSIATE OF POTASH. A yellowish precipitate, insoluble in excess. A black precipitate, in- soluble m excess. A black precipitate, in- soluble IB excess. The same ; insoluble in excess. A black precipitate, in- soluble m excess. RED PRUSSIATE OF POTASH. A slightly yellow preci- pitate, soluble in Muri- atic Acid. A white precipitate. A white precipitate, sol- uble in Muriatic Acid. A reddish brown preci- pitate, insoluble in Mu- riatic Acid. A white precipitate. A black precipitate, in both acid and neutral solutions. A dark brown precipi- tate, in both acid and neutral solutions. No immediate precipi- tate, but shortly a yel- low one. A red precipitate in acid solutions. A black precipitate, in- soluble in excess, part- ly soluble in Potash. The same ; solution must be neutral. A brown precipitate, sol- A yellow precipitate, so- uble m a large excess. lution tujrns ^ker. A white gelatinous pre- cipitate. A white precipitate, turning blue. The same ; approaching to violet. The same, insoluble in excess. The same. The same. No precipitate. Tliesame. The same. The same. The same. No precipitate in any so- lutions. Generally a brown pre- cipiute, in ether, acid, or neutral solutions. A dark brown precipi- tate. "^ A dark brown precipi- A brown precipitate, sol- uble in excess. A brown precipitate, sol- uble in excess, repre- cipitated by Muriatic Acid. A yellow precipitate, sol- uble in excess. A red precipitate, solu- ble in an excess. An emerald green color. A white gelatinous pre- cipitate. ; No precipitate at first, but shortly the whole I forms a thick jelly. A white precipitate, in- soluble in AlnnaUc Acid. A yellow precipitate, soluble in Muriatic Acid. No precipitate. A pale yellow precipi- tate, soluble in Muria- tic Acid. A yellowish green pre- cipitate, insoluble in Muriatic Acid. A reddish brown preci- piUte. A reddish brown preci- pitate, turning wnite. A yellow in most eola- tions, but none with the Perchloride. The same. No precipitate. A white precipitate, sol- uble in Munaiic Acid. A greenish precipitate, j No precipitate. A brown precipitate. A black precipitate, sol- uble in Potash. No precipitate. A grayish white preci- pitate. No action with the Acid, but a brown precipitate with the Oxide. The same ; soluble in excess. No precipitate. No precipitate. No precipitate, but short, ly a slight opacity. 11 No precipitate. A yellowish precipitate, ■olnble in ezcees. The tame. No precipitate. No precipiute. A brown precipitate, in Alkaline solutions. The same. The same; solnble in excess. The same, or in excess. A dirty green precipitate, unless Tartaric Acid be present, then no preci- pitate. A precipitate, soluble in excess. A black precipitate, slightly soluble in ex- cess. The same, if Muriatic Acid be added. A yellowish green pre- cipitate. No precipiute. No precipiute. An orange or olive yel- low precipitate. No precipitate. No precipitate. •A|^eep orange prccipi- No precipitate. No predpiUto. The same. A brownish red precipi- tate. ^ A brown precipiute. The same. i 826] A TABLE OF ANALYTICAL CADMIUM LEAD BISMUTH r PROTOXIDE ( PEROXIDE COPPER, DEUTOXIDE . SILVER .... MERCURY, PROTOXIDE MERCURY, PEROXIDE PLATINA GOLD . . TIN, PROTOXIDE TIN, PEROXIDE ANTIMONY . CHROMIUM . VANADIUM . COLUMBIUM . IRIDIUM . . RHODIUM . PALLADIUM . OSinUM . . TEU.URIUM . TITANIUM . TUNGSTEN . CHANIUM • MOLYBDENBM r OXALIC ACID. An immedUta preci- pitate, soluble in Ammonia. An immediate fihUe precipitate. No imm6diftt« preeipi- tat«, but after a time a granular one. IODIDE OF POTASSIUM. A yellow precipitate, ■oluble in a great ex- cess. A brown precipitate, soluble in excess. A greenish precipi- A while precipiUte, late. soluble in a great ex- A white precipitate, ■oluble in Ammonia, A white precipitate. A white precipitate, but none m the Per- chloride. No precipitate. A dark color, and shortly the Gold is precipitated. A white precipitate. No precipitate. A white preeipitato, caused by water. No preeipitata. eesa. A yellowish precipi- tate, soluble in excess. SULPHATE OF POTASH. A white precipitate, Tery insoluble. No precipitate, except from the water of so- Intion. No precipitate. A white precipitate, unless the solution be diluted ; soluble in water. PHOSPHATE OF SODA. A greenish yellow pre- 1 A white precipitate, cipitate, rendered black by an excess and at length diasolres. A fine scarlet precipi- tate, soluble in excess and in Muriatic Acid. A deep brown color, and precipitale,which boiling reduces. A dark color, and a yellowish precipitate. A yellowish precipi- tate, turning red, soluble in excess. No precipitate. The same. A greenish precipi- tate, eoluble m Moiri- stie Acid. Dissolves the Ozirde. Noaetioo. Tnms darker, but ia not precipitated. A white floeculeatyr*- upitate. A white precipitate. No precipitate. No predpitate. A white precipitate, partial. No precipitate. The same. No precipitate. No precipitate. Fused with it, the Oz> ide remains after boiling. No precipitate or ac- tion. Fused with the BisnI- phate, the whole dia- . solves in water. An orange yellow pre- cipitate. No precipitate or ao- twn. A white precipitate. A white precipitate, soluble in Potish. A white precipitate. A greenish white prjB- cipitate, soluble in Ammonia. A yellow predpitate, soluble in Ammonia. A. white precipitate. A white precipitate in most, but none in the Percnloride. No precipitate. No precipitate. A white precipitate. A white precipitate. The same. A light green precipi- tate. No precipitate. Does not form a doable ■alt. No doable salt. CHEMISTRY— Continued. [827 METALUC ZINC. Is precipitated as small metallic spangles. Precipitates in a crystal- line metallic state. Precipitates it from the milky soliilion even as a spongy mass. Zinc and Iron both preci- pitate nietallic copper Irom all its solutions. Is precipitated in a metal- Uc state. Forms a gray coating, which is an amalgam. Same aa Protoxide. A black metallic powder. BEFORE THE BLOWPIPE. Heated with Soda on charcoal, in the inner flame a brownish red powder sublimes. Heated on charcoal with Soda, ia re- duced to metallic globules, which are malleable, a yellow powder sublimes —produces clear glass with Borax. On charcoal are easily reduced to brittle nietallic f^lnbulea— a yellow Oxide sublimes ; with Borax, a clear glass. Outer flame with Borax, a fine green bead ; inner flame dirty red ; with Soda is reduced. With Borax in the outer flame a milky glass; with Soda is easily reduced. Heated in a glass tube with a little Soda, Mercury sublimes and con- denses m small globules. OBSERVATIONS. A brown boiky coating. Small grayish white span- gles of Tin. A white jelly. Hydrogen Gas is disengaged. Precipitated in the form of a black powder. Same aa Protoxide. Completelr reduced, but gives no color to fluxes or flame. No precipitate. Precipitated aa a dark powder. Precipitated firom the dou- ble Chloride of Rhodium and Soda. Precipitated in a metallic Same as Platina, insoluble in all acids except Nitro-Muriatio. Easily reduced with Soda: deprives a bead of Copper and Microcosmic Salt of its green color. Reduced on charcoal ; forms a white enamel with glass ; does not dissolve easily m Borax. Reduced with Soda, rapidly oxidizes and sublimes in the outer flame as a thick white smoke. A fine emerald green bead, both in the inner and outer flame, with fluxes. I In the inner flame, with Borax, a green glass • outer becomes yellow. Effervercei with Soda ; a clear jrlass with Borax, ol the Phosphoric Salt. Distinguished by Sulphuretted Hydrogen, and may be sepa- rated from all the above by a bar of Zinc. Solutions of Lewi give a precipitate with Sulphuric Acid and ^ulpbate8, and therefore may be distinguished frcm most other metals. Muriatic Acid also precipiutes Lead, but wa- ter dissolves the precipitate. May be detected by giving a precipitate with waUr alone, and by lU reaction with Potash and Sulphuretted Hydrogen. ^their hfhfr' can b«/««ily distinguished from other salU by their behavior with Ammonia and Potash. ^sIirdlJ'w'.''^i \V°'^\*'"'*° ?*''"« P'«ipit*te insoluble in SiLuJi^'s! '" '"""'"•^ ^^'"^ distinVishes it {^^ ^^i^^h^A^"''^ ^'**? '"''"« Precipitate insoluble in acids. ^uT^lfuZ'^arof^T^Z^^' by S'phnrettad Easily recognized by its behavior with Potash and Ammonl. • may be separated by Muriate of Potash. Ammoma , Protochloride of Tin gives a deep purple color and precipitate »m"r»VX^r'Sl^'^'^ ''" ^""' which dStin'^it; ""J-'SSh^k^Jr ^"'^ "'^ ^''''' " "--. » •"-w-t The Peroxide is insoluble in all acids after ienition • Nitri* Acid oxidixea Tin, but does not dissolve the Sr ' The Oxide is volatile and insoluble in Nitric Acid : mav be di. »;^'ut/-^t^o^tS^ffir«^'«<^H^«^-^en^ Its solutions are W"*"/ ^en and may be distinguished from tions by Sulphuretted >Iydrogen: ..a iTuiuuuuB are usuaii most other solutions 1 ^^liiuSK^AlLSli;^.'"' ^f^^ ^-I~n by Hy- ^Vuble'i^ waS.^""""' "' Carbonated AlkaU. the whole iM Precipitated aa a dark powder. Ta precipitated as a black powder. A deep blue color is pro- In Muriatic Acid a bine Oxide is formed. In a Muriatic solution of the acid a blue and red powder. No action with fluxes ; no odor ; may be cupelled with lead. No action with fluxes. Same as Rhodium. Gives a strong odor of Chlorine ; has no action with fluxes; maybe cu- pelled with lead. A white glass when cold, with flux- es ; fumes when heated alone. With Soda, a yellow glass, opaque when cold, with Borax, and inner name a blue glass. With Borax, a clear glass in the outer flame, yellow in the inner ; blood- red with Iron and Phosphorous Salt. On Platinum with Borax, a clear yel- low glass, outer flame dirty crreen • not volatile. ' Sublimes aa a white powder : a clear glass with Borax. ^watlr^'but^rfi!;^?''* of Potash, the result is not *>luble in Tott ^^^^'''' "* ^"'■"'^*' '^"«'' producing v«io«« Insoluble in acids a^r ienition; distinguished and separated iiohoK^ ^ '"^' '^^ "l^^We t-Woride is soffii^ TheCyanideof Mercury will easily separate Palladium as a yellow precipitate ; the Chloride Is soluble in AIcohoL '^SllatioJ.*^*^ ^^'' * ^"^^^ precipitate; «.p.rated by »Iay be sepamted from most other metals, combined with Chlorme or Hydrogen-both compounds being volatile. ''i.'S'^if '*^**'^ ^y^^""** '. distinguished from other metals by moS '"""^ "^ ^"'* "•* Hydrosulphate of Am- Sulnhuric, Nitric, and Muriatic Acids precipitate its Alkaline mSc Ac^d *""^^ ^'*"'"^ *'^^° *^*^*'* *'*^ ^''*^ Separated from most metals by dissolving in CWrbooate of Ammonia or Soda ; its solutions are green. Distinguished by Carbonates, but separated by Hydroaulithata ofAmmoma. * IRREGULAR PAGINATION 820 TESTS. TEXTILE FABRICS. 821 until it is released. The motion of the armature is transferred to a notched wheel, the Bpindle of which carries the hand on the dial. In the same case with each telegraph is an alarum which is also worked by the electric circuit, only at the time when the com- mutator arm is placed in the position of "rest," and that of another station is moved on "telegraphs." The alarum continues to sound until the arm of the telegraph, which is to receive a message, is also placed on the telegraph, when the instruments begm to work, making about 35 revolutions, or 1,060 double strokes of the armature per Printing telegraphs are also worked by the electric current only, without the aid of clockwork Their arrangement is similar to that of the indicating telegraph. In place of the hand on the dial, there is a type wheel with 30 springs, each carrymg a type; it stops with the hand of the indicating telegraph, at which moment a hammer placed below the wheel strikes against it, and prints the letter on a strip of paper, which passes over a blackened roller turning round with it so as always to oflfer new surfaces to the hammer. The hammer is worked by a magnet, which is excited by the same battery which works the type wheel : its current is continually broken and restored by the movements of the armature of the type wheel ; but as the type wheel stops, the current becomes permanent, and accumulates sufficient power to raise the hammer, which in so doing breaks its own current and falls back again. ,,.,.,. ^, v -„^ The printing telegraph is placed always by the side of the indicating telegraph, and records each message on both or all stations. . By this means mistakes in the transmission of the messages are made morally im possible. The current being always broken on both or all the stations, currents arising from bad insulation of the line wire will not influence the harmonious working ot the instruments, as long as these currents are not strong enough to work one or the other instruments by their own action, and the receiver of the message will always be able to interrupt and speak to the communicator. Besides, an unlimited number <>» telegraphs and other instruments for communicating particular signals may be included in the circuit of the same line-wire. , ., . x- i.i. 2. Another telegraph is peculiarly adapted to record on both stations the message delivered by the common English needle telegraph. Two magnets by naeans of two pins make dots in two different lines on a strip of paper which is nioved by clockwork. Dots on the upper line correspond with a movement of the needle to the right, and dots on the lower line correspond with that to the left . i. j Instead of needle telegraphs peculiar communicating instruments nnay be used con- sisting either of a pair of keys onTy, or of a complete key-board, which by pressing down one of them causes the conventional sign representing the letter marked on it to be orinted in a double line of dots. , , , t. *^ 3. A double needle telegraph, with electro-magnets and worked ^7 one line-wire. 4. An alarum, by which intermediate stations, when excluded from the line-wire, may be called into the circuit , . , , _ . , • « j,« 6. An alarum with two large cast-iron bells, which are placed on evel crossings, Ac., along railways and serve to announce the departure of each tram along the line. Ihe ffare surrounded by clockwork, which is released by a current of longer duration than is required to work the telegraphs. , . , . . .t .^ u„ ««„*oil 6. An instrument which is used to detect bad insulation in the gutta percha coated 7 Y galvanometer to test the insulation of the line-wire, and another by which defects in the line-wire may be pointed out, without leaving the end stations. 8. Gutta percha coated electric line-wire, which was first invented by Mr. Sumens, and applied by him on a large scale, since 1847. 9. An improved Morse's telegraph worked by secondary power. TELLURIUM, is a metal too rare and high-priced to be used in the arts. TERRA-COTTA, literally baked clay, is the name give to statues, architectural decorations, figures, vases. Ac., modelled or cast in a paste made of pipe or potter s cla^ and a fine-grained colorless sand, from Ryegate, with pulverized potsherds^ slowly dried in the air and afterward fired to a stony hardness in a proper kiln. See Stonb, Amificiai. TERRA DI SIENA, is a brown ferruginous ochre, employed m painting. TEST LIQUORS. To reduce an alkaline, acid, or a neutral saline solution ot a certain strength to one of any other strength. Let a =- the given strength per cent of S ouid • 6 - 100 ; - the desired strength ;x^the volume of the (Tiluted solution Example. Let an alkaline solution contain 40 per cent of alkali : if it is to be reduced , - . ao 4000 iRR.fl. to one containing 24 per cent, then the above formula gives - a; — — — lot) o, hence if 100 measures of the liquid a be diluted into 166 measures, it will then contain ^VfiS-STwe chemical reagents of any kind, which indicate, by special characten, 1421 r -- _ - r o --- 1 1 c 1 I f 1 < c ' 1 ' 1 c 1 1 a_u ■ - 1 1 - °J • _ . --&, .rzs the nature of any substance, simple or compound. See Assay, the several metal^ acids, Ac TEXTILE FABRICS. The first business of the weaver is to adapt those parts of his loom which move the warp, to the formation of the various kinds of ornamental figures which the cloth is intended to exhibit This subject is called the draught, drawing or read- ing in, and the cording of looms. In every species of weaving, whether direct or cross, ^e whole difference of pattern or effect is produced, either by the succession in which the threads of warp are introduced into the heddles, or by the succession in which thoie heddlos are moved in the working. The heddles being stretched between two shafts of wood, all the heddles connected by the same shafts are called a leaf; and as the operation of in- troducing the warp into any number of leaves is called drawing a warp, the plan of suc- cession is called the draught. When this operation has been performed correctly, the next part of the weaver's business is to connect the different leaves with the levers or treddles by which they are to be moved, so that one or more may be raised or sunk by every treddle successively, as may be required to produce the peculiar pattern. These connex- ions being made by coupling the different parts of the apparatus by cords, this opei'ation is called the cording. In order to direct the operator in this part of his business, especially if previously unacquainted with the particular pattern upon which he isemployed, plans are drawn upon paper, specimens of which will be found in figs. 1420, 1421, &.c. 2^20 /J These plans are horizontal sections of a loom, the j jillgM^ ^ heddles being represented across the paper at a, and "^'^''^^^^^ the treddles under them, and crossing them at right angles, at b. In figs. 1420 and 1421, they are re- presented as if they were distinct pieces of wood, those across being the under shaft of each leaf of heddles, and those at the left hand the treddles. See Weaving. In actual weaving, the treddles are placed at right angles to the heddles, the sinking cords descending perpendicularly as nearly as pos- sible to the centre of the latter. Placing them at the left hand, therefore, is only for ready inspection, and for practical convenience. At c a few threads of warp 45 GIB are shown as they pass through the heddles, and the thick lines denote the leaf with which each thread is connected. Thus, in fig. 1420, the right-hand thread, next to a, passes through the eye of a heddle upon the back leaf, and is disconnected with all the other leaves; the next thread passes through a heddle on the second leaf; the third, through the third leaf; the fourth, through the fourth leaf; and the fifth, through the fifth or front leaf. One set of the draught being now completed, the weaver recommences with the back leaf, and proceeds in the same succession again to the front. Two sets of the draught are represented in this figure, and the same succession, it is understood by weavers (who seldom draw more than one set), must be repeated until all the warp is included. When they proceed to apply the cords, the right-hand part of the plan at h serves as a guide. In all the plans shown by these figures, excepting one which shall be noticed, a connexion must be formed, by cording, between every leaf of heddles and every treddle ; for all the leaves must either rise or sink. The raising motion is effected by coupling the leaf to one end of its correspondent top lever ; the other end of this lever is tied to the long march below, and this to the treddle. The sinking connexion is carried directly from under the leaf to the treddle. To direct a weaver which of these connexions is to be formed with each treddle, a black spot is placed when a leaf is to be raised, where the leaf and treddle intersect each other upon the plan, and the sinking connexions are left blank. For example, to cord the treddle 1, to the back leaf, put a raising cord, and to each of the other four, sinking cords ; for the treddle 2, raise the second leaf, and sink the remaining four, and so of the rest ; the spot always denoting the leaf or leaves to be raised. The figs. 1420, and 1421, are drawn for the purpose of rendering the general principle of this kind of plans familiar to those who have not been previously acquainted with them ; but those who have been accustomed to manufacture and weave ornamented cloths, never consume time by representing cither heddles or treddles as solid or distinct bodies. They content themselves with ruling a number of lines across a piece of paper, sufficient to make the intervals between these lines represent the number of leaves required. Upon these intervals, they merely mark the succession of the draught, without producing every line to resemble a thread of warp. At the left hand, they draw as many lines across the former as will afford «« interval for each treddle ; and in the squares produced by the intersections of these linet, they place the dots, spots, or ciphers which denote the raising cords. It is also commoa to continue the cross lines which denote the treddle a considerable length beyond the intersections, and to mark by dots, placed diagonally in the intervals, the order or sne- fi ^^ TEXTILE FABRICS. oeaaion in which the treddlea are to be pressed down in weaving. The foracr of theit modes has been adopted in the remaining fig». to 1429; but to save room, the latter has been avoided, and the succession marked by the order of the figures under the intervals which denote the treddles. .<.,,, . ^ i. .i. ^ Some explanation of the various kinds of fanciful cloths represented by these plana, mav serve further to illustrate this subject, which is, perhaps, the most important of any connected with the manufacture of cloth, and will also enable a person who thoroughly studies them, readily to acquire a competent knowledge of the other varieties in weaving, which are boundless. Fig>^. 1420 and 1421 represent the draught and cording of th« two varieties of tweeled cloth wrought with five leaves of heddles. The first is tne re- eular or run tweel, which, as every leaf rises in regular succession, while the rest arc funk, interweaves the warp and woof only at every fifth interval, and as the successioa is uniform, the cloth, when woven, presents the appearance of parallel diagonal ines, at an aa-le of about 45° over the whole surface. A tweel may have the regularity ol its diagonal lines broken by applying the cording as in fig, 1421. It wil be observed ^at in ^Ih figures the draught of the warp is precisely the same, and that the whole differ- ence of the two plans consists in the order of placing the spots denoting the raising cords, the first being regular and successive, and the second alternate. , , , „..v Fies 1422 and 1423 are the regular and broken Iweels which may be produced with eight leaves. This properly is the tweel denominated satin in ^^e^ silk^manu^^^ 1422 1423 r 1 o \ ' 1 > 1 ' ' 1 1 o 1 1 o 1 I , __o U 1 1 c m!'^5d7ff 11346 although many webi of silk wrought with only five leaves re- ceive that appella- tion. Some of the finest Florentine silks are tweelei with sixteen leaves. When the broken tweel of eight leaves is used, the effect is much superior to what couU be produced by a smaller number; for in this, two leaves are passed in every in- terval which gives a much nearer resemblance to plain cloth than the others, /or this reason it is preferred in weaving the finest damasks. The draught of the eight-leaf tweel differs in nothing from the others, excepting in the number of leaves. Ihe diHer- ence of the cording in the broken tweel, will appear by inspecting the ciphers which mark the raising cords, and comparing them with those of the broken tweel of five leaves Fit;. 1424 represents the draught and cording of striped dimity of a tweel of five leaves. This is the most simple species of fanciful iweeling. It consists of ten 1424 leaves, or double the number of the common tweel. These ten leaves are moved by only five treddles, in the same manner as a common tweel. The stripe is formed by one set of the leaves flushing the warp, I - — 1— - fn M | | °|"i;l°L I and the other set, the woof. The figure represents i ' I : -pet-- "^11 a stripe formed by ten threads, alternately drawn '■ 1 11 rUiry °lll3 through each ofthe two sets of leaves. In this case, ,M94,si22^^ ^^^ ^^^.p^ ^j ^^^ intervals will be equally broad, and what is the stripe upon one side of the cloth, will be the interval upon the other, and rice versa. But great variety of patterns may be introduced by drawing the warp in greater or smaller portions through either set. The tweel is of the regular kind, but may be broken by placing the cording as in fig. 1421. It will be observed that the cording-maiks of the lower or front leaves are exactly the converse of the other set- for where a raising mark is placed upon one, it is marked for smkmg in the other; that is to say, the mark is omitted ; and all leaves which sink m the one, are marked for raising in the other: thus, one thread rises in succession m the back set, and 1425 four sink ; but in the front set, four rise, and only one sinks. The woof, of course, passing over the four sunk threads, and under the raised one, in the first instance, is flushed above ; but where the re- verse takes place, as in the second, it is flushed below ; and thus the appearance of a stripe is formed. The analogy subsisting between striped dimity and dornock is so great, that before noticing the plan for fancy dimity, it may be proper to allude to the dornock, the pUn of which is represented The drau«^ht of dornock is precisely the same in every respect with that of striped dimitv It ''also consists of two sets of tweeling-heddles, whether three, four, or hve leav-es are used for each set. The right hand set of treddles is also corded exactly in the same way as will appear by comparing them. But as the dimity is a continued stripe i ^ .3 ^ J TEXTILE FABRICS. from the be^nning to the end of the web, only five treddles are required to move tea leave* The dornock being checker-work, the weaver must possess the power of pe- Tersing this at pleasure. He therefore adds five more treddles, the cording of which i« exactly the reverse of the former; that is to say, the back leaves, in the former case, having one leaf raised, and four sunk, have, by working with these additional treddles, one leaf sunk and four leaves raised. The front leaves are in the same manner reversed, and the mounting is complete. So long as the weaver continues to work with either •ct, a stripe will be formed, as in the dimity; but when he changes his feet, from one set to the other, the whole effect is reversed, and the checkers formed. The dornock paU tern upon the design-paper, yig. 1425, may be thus explained: let every square of the design represent five threads upon either set of the heddles, which are said by weavers to be once over the draught, supposing the tweel to be one of five leaves; draw three parallel lines, as under, to form two intervals, each representing one of the sets ; the draught will then be as follows : — 1 The above is exactly so much of the pattern as is there laid down, to show its ap- pearance ; but one whole range of the pattern is completed by the figure 1, nearest to the right hand upon the lower interval between the lines, and the remaining fic^ures, nearer to the right, form the beginning of a second range or set. These are to be re- peated in the same way across the whole warp. The lower interval represents (he five front leaves ; the upper interval, the five back ones. The first figure 4, denotes that five threads are to be successively drawn upon the back leaves, and this operation repeated four times. The first figure 4, in the lower interval, expresses that the same is to be done upon the front leaves; and each figure, by its diagonal position, shows how often, and m what succession, five threads are to be drawn upon the leaves which the interval in which it is placed represents. Dornocks of more extensive patterns are sometimes woven with 3, 4, 5, and even 6 sets of leaves; but after the leaves exceed 15 in number, they both occupy an incon- venient space, and are very unwieldy to work. For these reasons the diaper harness ia m almost every instance preferred. Fig. 1426 represents the draugj;it and cording of a fartciful species of dimity in which it will be observed that the warp is not drawn directly from the back J426 to the front leaf, as in the former examples; bul when it has arrived at either external leaf, the draught is reversed, and returns gradually to the other. The same draught is frequently used in tweeling, when it is wished that the diagonal lines should appear upon the cloth in a zigzag direction. This plan exhibits the draught and cording which will produce the pat- ti.o o«.,o..o 1 J u .u • *^^" "P®'* ^^^ design-paper in fig. 1420, a. Were all the squares produced by the intersection of the lines denoting the leaves and treddles vvhere the raised dots are placed, filled the same as on the design, they would produce the effect of exactly one fourth of that pattern. This is caused by the reversing of the draught, which gives the other side reversed as on the design ; and when all the treddles fi-om 1 to 16, have been successively used in the working, one half of the pattern will become complete The weaver then goes again over his treddles, in the reversed order Fri^PwT-\T V^.K^" ^^'7"^" '^'^ other half of the pattern will be completed. iZ ^, th } '^L""^ ^A^ ^";^^"- *^ ^^^ ^^'»^"' '^ '' ^^^y* ^»»^" * which includes half of the warp, and sinks all the rest ; while a exactly reverses t^e opera- lion. The spol-lreddles on the right hand work Uie row contained in the first six-spot leaves ; and those upon the left hand, the row contained in the second six. In working spots, one thread, or shot of si)Olling- woof, and two of plain, are successively inserted, by means of two separate shuttles. Dissimilar spots, are those whose sides are q.*ile different from each other. The draught only of these is represented by Jig. 1429. The cordin? depends entirely upon the figure. , r j » „„.>,or if thP Fig. 1430 represents any solid body composed of parts lashed together. 11 tne darkened squares be supposed to be beams of wool, connected by cordage, they wi 1 give a precipe idea of textile fabric. The beams cannot come into aciua contact, because, if the lashmg cords were as fine even as human hairs, they must still require ' 1430 space. The thickness is that of one beam and one cord; but if the cords touch each other, it may then be one beam and two cords; but it is not possible in practical weaving to bring every thread of weft into actual contact. Il may therefore be assumed, that the thickness is equal to the diameter of one thread ot the warp, added to that of one yarn of the weft ; and when these are equal, the thick- - .„. ness of the cloth is double of that diame- ^^^^ ler. Denser cloth woukl not be suffi- ^ ciently pliant or flexible. ^ Fig. 1431 is a representation of a sec- lion of cloth of an open fabric, where the round dots whicn represent the warp are placed at a considerable distance from each other. Fig. 1432 may be supposed a plain fabric of that description which approaches the most nearly to any idea we can form of the most dense or close contact of which yarn can be made susceptible. Here the warp is supposed to be so tightly stretched in ]432 the loom as to retain entirely the ^^^-r^^^-^ parallel state, without any curvature, ^^^Mi and the whole flexure is therefore given to the woof. This mode of weaving can never reallv exist ; but if the warp be sufficiently strong to bear any tight stretching, and the woof be spun very soft and flexible, something very near it may be produced. This way of making cloth is well fitted for those goods which require to give considerable warmth ; but they are sometimes the means of very gross fraud and imposition; for if the warp is made of very slender threads, and the woof of slackly twisted cotton or woollen yarn, where the fibrils of the stuff, being but slightly brought into contact, are rough and oozy, a great appearance of thickness and strength may be given to the eye, when the cloth is absolutely so flimsy, that it may be torn asunder as easily as a sheet of writing-paper. Many frauds of this kind are practised; TEXTILE FABRICS. 825 .. f'J/5'- 1433 13 given a representation of the position of a fabric of cloth in section, as It IS in the loom before the warp has been closed upon the woof, which still appears as a I'^^S straight line. This figure may use- A a /^ f**''y illustrate the direction and ratio ■^^^=^ of contraction which must unavoidably "V take place in every kind of cloth, ac- ,. ,. . ^ , irf is '• cording to the density of the texture, the dimensions of the threads, and the description of the cloth. Let a, b, represent on« thread of woof completely stretched by the velocity of the shuttle in passing between ine inreaos of warp which are represented by the round dots I, 2. Ac, and those distinguished by 8, 9, &c. When these threads are closed by the operation of the neuaies to form the inner texture, the first tendency will be to move in the direction i, 0, I, b, &c., for those above, and in that of 8 a, 9 a, &c., for those below ; but the contraction for a, b, by its deviation from a straight to a curved line, in consequence 01 the compression of the warp threads 1 6, 2 6, &c., and 1 a, 2 a, &c., in closin?, will produce, by the action of the two powers at right angles to each other, the oblique or diagonal direction denoted by the lines 1, 8— 2, 9, to^the left, for the threads above and that expressed by the lines 2, 8—3, 9, &c., to the right, for the threads below' xxow, as the whole deviation is produced by the flexure of the thread a, b, if a is sup- posed to be placed at the middle of the clolh, equidistant from the two extremities or selvages, as they are called by weavers, the thread at 1 may be supposed to move really m the direction 1 b, and all the others lo ai)proach to it in the directions represented Whilst those to the right would apjiroach in the same ratio, but the line of approxima- 1434 lion would be inverted. Fig. 1434 9'm^W^^W^^^^ii^^^0^i:^^%^<^^^^^ for lawns, muslins, and the middle kinu ol goods, the excellence of whicli neither consists m the greatest strength, nor in the greai?<;t lransi)arency. It is entirely a medium bet ween ^g.~ 1431 andyjg.^1432. In the eflbit? to give great strength and thickness lo cloth, it will be obvious that the common mode of ^vavinff, by c<»nstant intersection of warp and woof, although it may be perhaps the best which can be devised for the former, presents invincible obstruc- tions to the latter, beyond a certain limit. To remedy this, two modes of weavin*' are in conrimori use, which, while they add to the power of compressing a great quantify of materials in a small compass, possess the additional advantage of affording much facility for adding ornament to the superficies of the fabric. The first of these is double cloth or two webs woven together, and joined by the oi>eiation. This is chiefly used for 1435 carpets; and its geometrical prin- ciples aie entirely the same as those , . , . . * ....,, °^ P^^'** Q\oih, supposing the webs to be sewed together. A section of the cloth will be found in^ig. 1435. See Carpet Of the simplest kind of iweeled fabrics, a section is given in fig. 1436 The great and prominent advantage of the tweeled fabric, in 'point of texture, arises f rom the fa cility with which a very great quantity of materials may be put closely to- gether. In the figure, the warp is represented by ihe dots in the same slraiffht line as in the plain fabrics ; but if we consider the direction and ratio of contraction, upon principles h 1436 sunilar to those laid down in the explanation given of;^g. TlierwrslTall rea^iirdTscovS the very diflerenl way in which the tweeled fabric is affected ^ discover When the doited lines are drawn at a, b, c, d, their direction of contraction, instead ?h. "'r ??" r''^ '"'''?? ^' °^^^''"^^" ^^''''^' '' «"^y "P«" every fifth thread, and Ipnt^ r .k'"?'"*^^' T".^^ consequently be, to bring the whole into the form repr^ sented by the lines and dotted circles at a, 6, c, d. In point, then, of thickness from the upper to the under superficies, it is evident that the whol'e fabHc has increased S the ratio of nearly three to one. On the other hand, it will appear, that four thread or cylinders being thus put together in one solid mass, mighl be supposed only onj £ nt S r»ii ^ ^ strands of a rope before it is twisted; but, to remedy this, the thread being shifted every time, the whole forms a body in which much aggregate matter is compressed; but where, being less firmly united, the accession of strength acquired by the accumulation of materials is partially counteracted by the want of equal firmness of junction. The second quality of the Iweeled fabric, susceptibility' of receiving ornament, arises 1437 from its capability of being inverted at m pleasure, as in fig. 1437. In this figure ^^ we have, as before, four threads, and one alternately intersected; but here the TEXTILE FABRICS. W li and adds even ength 1488 89& ib«r tbreads marked 1 and i are under the woo^ whUe those marked 8 and 4 art above. , . , - tweeled work which produces an ornamental effect, m 1438 '«Pf«««^^^t**i'?^f .^^^^^ for BB nccumulation of matter can be r.d «dds even to the strength of a fabric, in ^^^^.^^^^^ -^ ^^^^ ^-^y^^^ The figure represents a piece of velvet cut m section, and of that kind which, be- . -^ ^ ^ ,- ing woven upon a tweeled ground, k known by the name of Genoa velvet 1st, Because, by combining a great quantitj rf matrrfal in a small compass, they afford great warmth. ^2d. From the great resist- L^TwhTch hey oTpose to Sternal friction, they are very durable. And 3d. Because ^^m The very natur^of the texture, they afford the finest means of rich ornamental dec»>. '^tZ use of velvet cloths in cold weather is a sufficient proof of the truth of the first. Th?manufacture of pl^^^^^^^ corduroy, and other stuffs for the dress of those exposed to the IddTnts of la^^^^^^^^^^^ the second; and the ornamented velvets and Wilton caroetins are demonstrative of the third of these positions. In tie figure the diagonal form which both the warp and woof of cloth assume, is very a^rttf?omlhe illness of the scale. Besides what this adds to Jhe Jtrength of^he S, the flushed part, which appears interwoven at the ^^^^ly shaded int^^^^^^ 1^ 2 &c., forms, when finished, the whole covering or upper surface. The prmciple, in so lar as regards texture, is entirely the same as any other tweeled fabric. fS. 1122, which represents corduroy, or king's cord, ;s merely f"ped velvet The princfple is the same, and the figure shows that t;^^ ^ ^^^^^^^^^ S^; 1439 ^^^^ ^Yilch are of the most flimsy and ,open description of texture; those in which neither strength, warmth, nor du- rability is much required, and of which nnenness and transparency are the chiel recommendations. ^T^^riS r^prese^nts colimon .auze,^_or /».u a -^f-ce very ^^^^^^^^^^^ TEXTILE FABRICS. 827 purposes. The essential difference between this description of cloth and all others, con- ine essenu ^.^^^ .^ ^^^ ^^^^ ^^.^^ ^^^^^^ ^^ twisted 1440 like a rope during the operation of weav- and hence it bears a considerable The twining of gauze is ing, analogy to lace. not continued in the same direction, but is alternately from right to left, ^nd vice versa, Mween every intersection of the woof. The fabric of gauze is always open, flimsy, and Uarparent;^but, from the turning of the warp, it possesses a.^.uncommon degree of strength and tenacity in proportion to the quantity of material which i contains. This qualify, together with the' transparency of the fabric, renders it Peculiarly adapted for or- Samental purposes of various kinds, particularly for flowering or figuring, fi her in the him, or by the needle. In the warp of gauze, there arises a much greater degree of c^nT action during the weavinsr, than in any other species of cloth ; and this »s produced i^ the turning, the twisting between every intersection of weft amounts precisely to one Slee revolution of both Threads ; hence this difference exists between ih^f and every other species of weaving, namely, that the one l'*'*^ thread of warp is always above the woof, and rf^^ sa^^es^aa^^s^pss^sa^^ jj^g contiguous thread is always below. Fig. 1124 represents a section of another species of twisted cloth, which is known by the name of catgut, and which differs from the gauze on y by being ^"^jected to a greater degree of twine in Weaving; for in place of one revolution between fa^h intersection a resolution and a half is always given; and thus the warp is alternately above and below, '^Fie^lk is"a\Sp^ficIarrepresentation of the most simple kind of ornamental net-work produced in the loom. It is called a whip-net by weavers, who use the terra whip for *^* any substance interwoven in cloth for ornamental purposes, when It is dis- tinct from the ground of the fabric. In this, the difference is merely ia the crossing of the warp; for it is very evident that the crossings at 1, 2, 3, 4, and 5, are of different threads from those at 6, 7, 8, and 9. Fiit 1126 represents, superficially, what is called the mail-net, and is merely a combi- ItuiLf conJSrgauze ^^ the whip-net in the same fabric. The gauze here beang in 1^^ the same direction as the dotted line in the former figure, the whole fabric is evidently a continued succession of right-angled triangles, of which the woof forms the basis, the gauze part , the perpendiculars, and the whip part the hypotenuaea The contraction here being very different, it is necessary that the gauze and whip parts should be stretched upon separate beams. In order to design ornamental figures upon cloths, the lines which are drawn from the top to the bottom of the paper may be supposed to represent the warp ; and those drawa Across the woof of the web ; any number of threads being supposed to be included be- tween every two lines. The paper thus forms a double scale, by which, in the first in- stance, the size and form of the pattern may be determined with great precision • and the whole subsequent operations of the weaver regulated, both in mounting and working his loom. To enable the projector of a new pattern to judge properly of its effect? when transferred from the paper to the cloth, it will be essentially necessary that he Bhould bear constantly in his view the comparative scale of magnitude which the design will bear m each, regulating his ideas always by square or superficial measuremenL Ahus, in the large design, fg. 1444, representing a bird perched upon the branch of a tree It will be proper, m the first place, to count the number of spaces from the point of the bill to the extremity of the tail ; and to render this the more easy it is to be observed that every tenth line is drawn considerably bolder than the others. This number in the design is 135 spaces. Counting again from the stem of the branch to the upper part of the bird's head, he will find 76 spaces. Between these spaces, there- 1444 fore, the whole superficial measure of the pattern is contained. By the measure of the lT\nlt\ lVM7\'r^ ""l'^ ^ ^r""! «^"^P^^^«' -^<^ ^"^ ^^ foundTbe nearly 6^«j inches in length by 8/_ inches in breadth. Now, if this is to be woven in a reed containing 800 intervals in 37 inches, and if every interval contains five threads sup- Td ?h^htT»,^<;°.l^-^'^'"^ ^V'y ^^^ P*^^"^^ '^^^^^ the length will be 624 £ch£ nLrlv nf th! i ^^A' ""''^'' °'*'^^ ' '^ ^^^^ ^^^ %"»"^ "P«° ^he cloth Would be ve^ Lstea^d of an IZ'ttZT'"''' "' '^^' T^ '^' P"P^^ ' ^"^ ^^ » ' 200 reed were ^ instead of an 800, the dimensions would be proportionally contracted. A correct idea being formed of the design, the weaver may proceed to mount his loom according t« he pattern ; and this is done by two perso^nfre of whTm tok^ T ^^tAT^"" instructions necessary for the other to follow in tying hfs clrds. rzg. 1445 IS a representation of the most simple species of table-line^n. wS merely 1446 an imitation of checker-work of various sizes : and is known in Scotland where ihm 828 TEXTILE FABRICS. TEXTILE MANUFACTURES. 829 \ ! 1446 extent of the design, and the means by which it is executed. Fig. 1446 is a design fvf a border of a handkerchief or napkin, which may be executed either in the manner ^J damask, or as the spotting is practised in the lighter fabrics. Textile fibres condensed. Mr. John Mercer's novel plan of transforming cotton and flax into fibres of a fine silky texture, while their strength and substance are increased, has recently excited much interest. He subjects them to the action of caustic alkaline lye, sulphuric acid, or to solution of chloride of zinc, of such strength and at such a temperature as produces certain remarkable changes in them, quite the reverse of what most people would have expected. The mode of operating according to this invention, upon cloth made wholly or partially of any vegetable fibres and bleached, is as follows: — The cloth is passed through a padding machine charged with caustic soda or caustic potash at 60° or 70° of Twaddle's hydrometer, at the common temperature of the atmo- sphere (say 60° Fahr. or under) ; then, without being dried, it is washed in water; and, after this, it is passed through dilute sulphuric acid, and washed again. Or the cloth Is conducted over and under a series of rollers in a cistern containing caustic soda or caustic potash at 40° to 50° Twaddle, at the ordinary temperature (the last two rollers being set so as to squeeze the excess of soda or potash back into the cistern) ; and then it is passed over and under rollers placed in a series of cisterns, which are charged at the commencement of the operation with water only ; so that when the cloth arrives at the last cistern, nearly all the alkali has been washed out of it After the cloth has either gone through the padding machine or through the cisterns, it is washed in water, passed through dilute sulphuric acid, and again washed in water. When grey or unbleached cloth, made from the above mentioned fibrous material, is to be treated, it is first boiled or steeped in water, so as to wet it thoroughly ; then most of the water is removed by the squeezer or hydro-extractor; and, after this, it is passed through the soda or potash solution, erature, and showing such till the instrument is disturbed. ° ° & To prepare the instrument for future observation, it is simply necessary to remoye 836 THERMOMETER. that end from its hook which is the farthest from the bulb ; to raise it^ till the instru- ment is nearly perpendicular; and then to slightly agitate it while the brass plate the nearest to the bulb is still suspended from its hook. The mercury will descend in the tube, and indicate the temperature of the air at that time, and when again suspended from its hook, is prepared for future observation. For determination of the solar radiation,— The instrument for this purpose must have a black bulb ; it should be placed nearly horizontal, with its bulb in the full rays of the sun, and if possible, so that lateral wind should not strike the bulb. The direc- tions for use are identical with that for the determination of the temperature of the air. THERMOMETER, SELF-REGISTERING, by Mr. Brooke. The Exhibition con- tained a wet and dry bulb thermometer, and apparatus for registering the tempera- ture they indicate. The registering apparatus consists of a pair of vertical concentric cylindei-8, supported on a table. The bulbs of the thermometers are underneath the table, through which the stems pass vertically, and are placed between the opposite sides of the cylinders and two lights. A narrow vertical hne of light brought to a focus by a cylindrical lens falls on the stem of the thermometer, and passing through the empty portion of the bore affects the paper. The boundary between the darkened and undarkened portion indicates the position of the mercury in the stem of the ther- mometer. Fine wires are placed across the slit in the frame, through which light falls on the stem. They intercept narrow portions of the light, and thus the scale of the thermometer is continuously impressed on the register, as well as the tempera- ture, a, 6, Jig. 144*7, are campliine lamps; 1447 c, d^ cylindrical lenses, by which a bright focal line of light is obtained ; e, the psyehro- meter, or wet bulb thermometer ; /, the dry bulb thermometer; g, two concentric cylin- ders, between which the photographic paper is placed ; A, the register, as it appears after the impression is developed; i, one of the rollers of a turn-table, on which the cylinders rest; j, the frame which contains the time- piece; k, a bent pin, or carrier, attached to the axis of the cylinders; this is carried round by a fork at the end of the hour hand of the time-piece. As this apparatus is necessarily placed in the open air, when in actual opera- tion it is provided with, 1, an inner cylin- drical zinc case, with sliding doors, to protect the sensitive paper from light, when the cy- ^ linder is removed from, and brought back to the photographic room; 2, an outer wind and water-tight zinc case, with water-tight doors for removing and replacing the cylin- ders, and for trimming the lamps, if lamps are used. The skilful application of photography by Mr. Brooke to register natural phenomena, with no more labor than that of supplying the cylinder punctually with prepared pa- per, is one of the most useful and beautiful uses to which photography has as yet been applied. Tlie paper is prepared so as to render it extremely sensitive to light, being first washed with a solution of isinglass, bromide of potassium and iodide of potassium, in the proportion of 1, 3, and 2, respectively ; and when required for use, it is washed with an aqueous solution of nitrate of silver, which causes the paper to be sufficiently sen- sitive to the action of light, so that if a beam of light be allowed to fall upon it^ an im- pression is made upon that part where the light falls, which becomes visible on being washed with a solution of gallic acid, with a small admixture of acetic acid. A light is placed near a small aperture, through which rays pass and fall upon a concave mirror carried by a part of the suspension apparatus of the magnet, and this reflection falls upon a piano-cylindrical lens of glass placed at the distance of its focal length from the paper on the cylinder. As the magnet is ever varying and making small excursions on one or other side of its mean position, the point of light traces a corresponding zigzag on the paper. The thermometer apparatus has no mirror and no reflector, the mercury in the tubes themselves, intercepting the pencils of light ; and thus this apparatus, throughout the day and nighty is constantly recording the slightest change of position of the magnets and the smallest changes of temperature. The object of this self-registering magnetometer above described is to determine the THERMOMETER. 837 direction and intensity of the earth's magnetism. Its direction is generally found by suspending a piece of steel previously magnetized, or in other words a magnet, by parallel threads of untwisted silk, and the bar settles in that position in which mag- netism causes it to rest, and which is called the magnetic meridian. The angle between the astronomical meridian and the magnetic meridian gives the magnetic declination which is the subject of research with the declination magnetometer; at present^ this value m London is about 22^° west of the astronomical meridian. Having determined the declination, the vertical plane is determined in which the force of magnetism is exerted. The angle which the magnet makes when freely suspended on this plane from the horizon is termed the dip. At present the dip at London is about 68° 40'. The force of magnetism exerted in this inclined direction can be resolved into two forces, the one acting in a horizontal direction, the other in a vertical direction, so that conjointly they shall produce exactljp^ the same force as the single force. The biplar, or horizontal force magnetometer is intended for measuring the variations of the horizontal com- Eonent of the variations of the force of magnetism. It consists of a magnet suspended y two halves of a skein of untwisted silk, kept at a certain distance apart If an un- magnetized bar were thus suspended, it would remain at rest only in that position ir. which the two parts of the suspension skein were without twist, and if it were turned out of this position, it would endeavor to resume its former position with a force pro- portionate to its weighty and the angle through which it had been turned. This prin- ciple is made the means of measuring the force of magnetism. A freely suspended magnet alwaj^s endeavors to rest in the magnetic meridian. The variations in the vertical component of the magnetic dip are the subjects of in- vestigation with the vertical force magnet, which is a magnet placed nearly at right angles to the magnetic meridian. It is kept horizontal, or nearly so, by weights balanced with extreme accuracy, and made to vibrate like a balance; and from its diflferent in- clination the variation of the vertical force of magnetism is determined. Thermoynetrical Table, by Alfred S. Taylor, Esq.— The accompanying therm ometrical table of Mr. A. Taylor, has been copied from a thermometer in his possession, graduated on the scales of Fahrenheit and Celsius. It has been designed to obviate the necessity f6r those perplexing calculations, so often rendered necessary by the use of different methods of graduation in England and on the Continent In most chemical works, we find, besides the rules given for the conversion of the degrees of one scale into those of another, comparative tables, which, however, convey no information beyond the bare fact of the correspondence of certain degrees. In this table, the attempt has been made to make it convey information on numerous interesting points, connected with temper- ature in relation to climatology, physical geography, chemistry, and physiology. There is another advantage which a table of this kind must possess over those hitherto published m works on chemistry. In the latter, the degrees on one scale only run in arithmetical progression, while the corresponding degrees on the other scale, are neces- sarily given m fractional or decimal parts, and at unequal intervals. Thus, in some of the best works on chemistry, a comparative table is printed, which is only fitted for the conversion of the Centigrade into Fahrenheit degrees, so that a person wishing to convert the Fahrenheit into Centigrade degrees, would have to revert to one of the old formula of conversion. This process must also be adopted whenever the Centigrade degrees are given in decimal parts, for all the tables yet published in English works, wrongly assume that the Centigrade degrees are always given in whole numbera The present table renders such calculations unnecessary, since the value of any degree, or of any part of a degree on one scale, i« immediately found on the other by looking at the degree m a paralle line with it The main divisions will, I believe, be found perfecUy occurate:-in single degrees a little inequality may be occasionally detected; but I have not found the error to be such as to affect the calculated temperature. Although the Fahrenheit and Centigrade scales are the two which are chiefly used in Europe, it has been thought advisable to carry out the parallel degrees of Reaumur's scale, by dote on the drawing of the tube. This table, therefore comprises in itself BIX distinct tables, assuming the necessity for each scale to be represented in whole degrees-with the additional advantages: Ist, that the space occupied is smaller, and the othLTwIf sclfel^ fractional part of a degree on one may be at once determined on ^ It is extraordinary, considering the great advances which have been recently made in physical science, and in the manufacture of philosophical instruments, that the makers of thermometers should still adhere to the ofd and absurd practice of marking on the Farenheit scale, the unmeaning words Temperate, Summer-heat, Blood-heat, Fever- heat, Spirits boil, Ac, when the instrument might be easily made to convey a large amount of information in respect to climate, as it is dependent on temperature. Thus the mean temperature of England, Ireland, and Scotland, with the maxima and minima, m B3a THERMOMETER. THERMOMETER. 839 CENTIGRADR REAUMUR. FAHRENHEIT. CENTIGRADE. REAUMUR FAHRENHEIT. Cblor. Cyanogen toL 190 Tte and Imd, p. c m. ; also Alloy 18 T. 4 L. (Phunben' solder). dat. loL Chloride zinc boila. Alloy 4 T. 1 L. m. Oxalic etlier, b. 1 -09. Salphuric acid, 1*67 boila. pr. steam, 10 at Pannaphthallne, m., aHoy 13 T. 4 L. melts. Oil of oranges, b. 0-835. Starch converted to dextrine. 180 pr. steam, 9 at. Tup., ▼. 63-8> Salphuric acid 165 binls. AUoy 10 T. 4 L. m. AHoy 9 T. 4 L. m. pr. steam, 8 at AHoy 8 T. 4 L. m. Alloy 7 T. 4 L. m. yjQ pr. steam 7 '6 at. Alloy I B. 3 T. m. pr. steam, 7 at AUoy 8 B. 38 L. 34 T. m. Oil elemi, b. 0-853. pr. steam, 6.5 at yg. ttetm, at Fusible; Elast, A. V. 137. 38. Alloy 8 B. 33 L. 36 T. m. 1 gn AUoy 8 B. 33 L. 34 T. m. Elaat A. V. 131 -67. Fulminating silver explodes. pr. steam, 6*6 at Zlast A. V. 126.86. Elast Turp. v. 33-6. pr. steam, 6 at. Elast A.V. UO.OS. Slaat Turp. ▼. 30. Sat. nit lime boils. Sulphur bums feebly. Elast A. V. 114-l.V IRQ , Terbromide Silicon, b. 4 pta, Nlphnrie add, aad 1 pt water mixed ; pr. steam, 4-5 at Mastich resin, m. Alloy 8 B. 16 L. 18 T. m. Kut A. y. 108*31 ; Temp, of certain factories. Nicotine distils. pr. steam, 4 at Elast A. v. 103.45. Fulminating gold explodes. AUoy 8 B. 16 L. 14 T. m. pr. steam, 3*6 at Cblor. cyanogen, m. : S. G. t -33. i^q Grape sugar to Caramel. Elaat A. V. 90.99. Sat oit ammonia boils. pr. steam, 3 at Pimeiic acid, m. ; Xlast A. T. 79-94. pr. steam, IS at 372 Zinc pnlTerirabie. ArseniouB acid vol : Saliculous acid k Dichlor. carbon, b. d. ■». 4"7. pr. steam, 1 1 at Fulminating mercury explodes. AUoy 16 T. 4 L. m. 362 Alloy 14 T. 4 L. m. Elast Turp. V. 60.8. Alloy 13 T. 4 L. m. Arsenic vol. : sugar melts ; hydrnret of bentule i Succinic acid meiU. Chloride benzole, m. 352 Alloy 8 B. 33 L. 84 T. m. ; Citrilene b. 0- AUoys 6 T. 4 L., and ] 1 T. 4 L. m. Sulphuret solid; iodine boils, d. r. 8*69. Malic acid m. Alloy 8 B. 33 L. 36 T. m. Oil of lemons boils, 0-848. Oil of Cascarilla b. 938. Alloy 8 B. 30 L. 34 T. m. . 342 Caoutcboucine boils. Elast Turp. V. 47*3. Sat acet potash boils; enpion b. Alloy 6 T. 4 L. m. 222 •A.lloy 8 B, 33 L. 38 T. m. Oxalic acid vol.; elast turp. V. 43*1 Alloy 8 B. 33 L. 30 T. m. 322 AUoy 8 B. 33 L. 40 T. m. AUoy 8 B. 33 L. 38 T. m Naphtha boils ; aUoy 8 B. 36 L. 24 T. m., alao 8 B. 99 1. 9S T. Prussian blue decomposed. AUoy 8 B. 16 L. 34 T. m. Oil of turpentine boils 0*86 ; dens. Y. 4*7. „ Alloy 8 B. 16 L. 33 T. m. viii Quinine m. Alloy 8 B. 30 L. 34 T. m. J oU juniper b AUoy 8 B. 32 L. 34 T. m. Rect petroleum b. Carb not sat boHa J ^ "*'>'■ « B. 16 L. 10 T. carb. pot sat. boils, j ^^j g g jg l. go T. m. 202 ETHERIFICATION ends; latent heat; tAhn rap. Alloy 8 B. 16 L. 8 T. m. ; camphilene b. 86. ; tngu of milk m Asphaltum melts; camphor melts, d. t. 6*31. Zinc malleable. AUoy 8 B. 16 L. 13 T. m. 292 Alloy 8 B. 16 L. 16 T. m. Gypsum converted to plaster. Sulphuric acid, 1*53 b. Elast A. V. 96*64. Tin and bismuth, p. r. melt; ancc. acid toU pr. steam locomotive boilers. 2g2 ETHERIFICATION begins. Cholesterine mehsk Elast A. V. 86-47. Oil black mustard b. ; maleic acid m. Peucyl b. 0*80. b-.272 PUoridaina solid. AUoy, 8 B. 10 L. 8. T. m. ,»«. Camphoric acid r. pr. steam, 3-6 at Elast A. V. 69*73. Sabacic acid m.; Elast. alch. r. 166*3. Sat mur. ammonia boils. Sat acet soda boils. Pyromeconic acid m. Elast A. V. 60-06. pr. steam, 3. at ' Sat nit soda boils. Cinnamic acid m.; caoutchouc melts. 120 ■ Alloy 6 B. I L. 4 T. m. Sat cblor. strontium boils. Elast A. V. 61*34. Byrvp boils 86 per cent ; chlor. calcium sat boils. Elast A, V. 47*3, Alloy 8 B. 8 L. 4 T. m. Chloric ether 1,837 boils; pr. steam, 1 -6 at Elast A. y. 43-34. Xlaene b.; Elast alch. t. 94*1. HO Phloridzine m. Elast A. V. 39*69. Alloy, 8 B. 8 L. 3 T. m. Oxalhydric acid, b. 1 -375. Water of the Dead Sea boils. carb. aoda, chlor. of barium, and chlorate potash boil. Salicioe m.; nitric acid, I'lSb. Hur. acid, 1*136 b. ' Sjrrup boils 63 per cent sugar. Chlor. alumina boils; water boils, bar. 31 313*76. Glauber salt sat boils. el 1 pt ice; 4 sulphuric acid; pr. steam, 1 at. inn. 100airat33«'=137-6.] ■*"" Elast A. ¥.=30 S. G. 636.] Water boils bar. 39 in. Perox. chlor. explodes. W. B. MADRID. W. B. EL SATTRE (between Dead Sea and Akabah.) COMAGILLAS. Mexican Springs. W. B. GAVARNIE PYRENEES. ▼olcanic mud; JORULLO, S. AMERICA. Oxychlorocarbonic ether b. Elast ether vap. 166; Elast A. V, 23-64. W. B. MEXICO. 7471 ft. eL W. B. SANTA FE BE BOGOTA. 8730 ft el. 90—1 Water boils ; CONVENT ST. BERNAND. 9734 ft. d. W B. FARM OF ANTI8ANA Andes, 13,000 ft. eL Chloric ether b. I ■34. W. B. aource of Oxus, CENTRAL ASIA. (16,600 ft. elev.) Elast A. V. 16*16. G«yier Springs, Ireland. Xlast A. V. 14-8. Syrup sat boils. Corrosive sublimate rolatilised. Elast A, V. 74-79. Margaritic acid ; castor oil m. Elast alch. V. 166-1. Syrup boils 80 per cent sugar. . 262 ^*'*- tartrate potass boils. Sat nitrate potass boils; heat borne by Sir J. Banks and Dr. Hydriodic acid boils 1 -7 ; also hydrobrom. acid 1'6. '*•■•* Elast A. V. 64*83; pimaric acid m. AUoy 8 B. 8 L. 6 T. m. ■ 252 ^'^"'^ ■*^"' ''*2 '»<>''•■ Elast alch. V. 133-3. ; dichL carbon t. Benzine melts ; hyd. acet acid boils (Tomar). Elast A. V. 66-64. Heavy muriatic ether b. Elast alch. V. 118-8. -242 Heat of fluid, beeswax. 80' Xltat alch. Tap. 30 is. S. G. 0-SlX Alloy 8 B. 8 L. 6 T. m. Sulphuric acid 1 -30 b. ; pyrogaUic acid m. Veratrine and benzaraide m. Accumulated temp, of air, EDINBURGH Acet acid 1*063 boils; nit. acid 1-30 b. Syrup boils 84 per cent sugar. '232 Sulphur melts, d. t. 6-65; bensoine m. Benzoic acid melts, d. v. 4-37. Salicine m. Zinc malleable; heat borne by Delaroch*. Sat chlor. sod. boils. Sat chlor. pot boila. Sat phos. soda boils. -non Muriatic acid 1 047 b. ; Elast A. T. 36*86. XCi Accumulated temp, of air, GENEVA. Asphaltum soft; iodine melts; elast ether V. S4a Elast A. V. 33*09 inches mercuiy; grape sugar m. Osmic acid volatilised. Sylvic acid m. Water boils lOM ft. dep. ; se1eni-im melts; water boils Kar. SL Water boils, 328 dep. ; W. B. DEAD SEA and SEA of TlBX- •01 9 Water boils bar. 30. rRIASL *^'« Water boils 631 ft. elevation. l»»«»* Water boils 1064 ft. elevation; osmic acid melta. Water boils 1600 ft. elevation; Reikiavik spr. Water boils 2138 ft. elevation. Water boils 2678 ft. elevation ; aUoy 8 B. 6 L. 3 T. ■. Water boils 3221 ft elevation. Water boils 3766 ft. e!e-/ation. Water boils 4313 ft. elevation. Water boils 4863 ft elevation. •202 Water boils 6415 ft. elevation. Fusible metel, 8 R 6 L. 3 T. m. ; chloral b. d. t. S. - Elast alcb. Taps. 63. I^j W. B. St Gothard, 6807 ft. elevation. W. B. Mt WUUam, AUSTRALLl, 8300 ft. eL Water boils at Quito, 9341 ft. el Sodium melts; Trinchera springs S. AMERICA. • 192 Water boils summit of Etna, 10,955 ft. eleT. Elast ether vap. 134*8 ; akh. Tap. 43*8. Alcohol b. 0*967, 85 per cent Nitric acid 1 *638 boils ; alcohol b. 0*968, 30 pr. e. Ozokerite ni. 182 Water boils Mont Blanc summit, 16,630 ft. eL San Germano bath, NAPLES. Starch dissolves ; alch. b. 0-870, 71 per cent AIX LA CHAPELLE, spr. max. t Latent heat, petroleum Tap., also oil Pajf. |— Alcohol boils, 0-736, 86 per cent Tliermal spr., I. LUCON. Alcohol boils, 0-794, also 0*818, 94 per oeofc to Iflft ■ 173 Naphthaline melts. 840 CENTIGRADEL THERMOMETER. REAUMUR. FAHRENHEIT. THERMOMETER. 841 Pitch melta. Tapor bath, FINLAND, max. t. Fercblor. carbon rap. l-Sft. Uelenine in. lUat A. V. 9*4«j ether Tap. 80.3. Starch converted to sugar. 70 _I Baden Baden Springs, max. C CALPEE, 1NI>IES, max. t BAGNKRES DE LUGHON, epr. Ihwt A. V. 7-48., S. O. 017; ether, rap. 67& H Albnraen opaline. Elast A. V. 6-87. , Heat of fluidity Spermaceti .-I Heat of fluidity nulphur. Vapor bath, RUSSIA. Chloroform, b. d. v. 4-3. Htele Mid {1-6) 68 pts. water, 13 pU. from 60«. 60— | Mariana aprings, S. AMERICA. Zlaat ether. Tap. 61.9. I •"I BARBARY, max. t, Abietic arid m. Ammonia 0-936 b. Elaat, A, V. 43. OASIS OF MOORZOUK, max. t. FEZZAN, AFRICA, max. t. Terchlor. silicon, b. BAGNERES DE BIGORRE, apr. Amalgam 8 B. 6 L. 3 T. and 3 mercury m. 50~| Concent, sulphuric acid evaporates. Palmitic acid no. Hamman Ali springs, BARBART. PAMPAS, SOUTH AMERICA. CXNTRAL AFRICA, «, t; BASSORA, max, t ' PONDICHERRY max. t -,,, ■ Chloronapbthalese m. PHILOX, EGYPT, CAPE OF GOOD HOPE, max. t. Myrtle wax m. SENEGAL, 8. t. ^1 BAREGE, spr. ' MADRAS, CAIRO, max. t Onmartoi spring, GREENLAND. GUADALOUPE, max. t PARIS 1793, EQUATOR, max. t. _ Eupion, b 0"%. - • OUAHAXUATO MINES, 1700 ft. deep, 7034 ft el. I MEXICAN MINES, max. t "' 8TRA3BURG, VIENNA, max. t *Man, min. t. TE.XAS, 8. t. , MARTINIQUE, max. t — I STOCKHOLM, max. t 1 Consol mines. CORNWALL, 1740 ft. COPENHAGEN, WARSAW, max. t. EAUX BONNES, Pyrenees. max. t. o«" SURINAM, ROCHAT, spr. CAIRO, s. t. H IS. MALTA, EGYPT, m. s. t. on PONDICHERRY, m. t '^' Schlangenbad Spa, CUMANA, m. t BRAZILS, m. t ; BARBARY m. s. t. CEYLON, SENEGAL, BATAVIA,m. t MADRAS m. t. ■ CONGO, MANILLA, BENARES, HAVANNA, m. t. J BOMBAY, m. t; ITALY, ro. a. t Date tree, VERA CRUZ. "" Artasian well (300 ft.), BRAZILS, JAMAICA, m. t. RIO JANEIRO, m. t. CANTON, MACAO, m. t. BAGDAD, m. t —I AMebyde, b.; CARACCAS, CAIRO, m, t. Sqrcbellet, rati, t Ehut. ether vap. 93-«, alch. b. 92 per cent -SIT Elast. A. V. ll-fi. Phoaphorus bnma violently ; acetic ether U OU of cedar melu, Carlsbad Spa. Elast. A. V. 10-4. 162 H^t of fluidity lead. Albumen coaguL; acetic ether boils; Pisciarelli ipriqp.NAPLCi Kochbrunnen, Wisbaden. Stearic acid melts. Elast. A. V. 8-4. STEAMBOAT'S ENGINE ROOM, W. INDIES. HECLA, EARTH AT SUMMIT. 252 Thermal epr., TAJURAH AND SHOA. White wax melU; pyrox. spirit boils. Wiesbaden Spa; hydriod ether b., S. G. 1-93. Plombieres spr. Ambergris spr. Ischla springs, NAPLES; Leaker spr. 6000 ft. eL __ Aix-Ia-Cliapello Spa. I ", J42 ^*"o* "fax melts. Ammonia 0-94 boils; pyroxylic sp. h. 0-833 ; elast A. V. ••»4 Bluriatic acid 1-19 boils. UPPER EGYPT, in a tent; Aries spr. Elast A, V. 6-14. Margaric acid melts. Formic ether b. S. G. 916. J32 Atelone boils (pyroacetic spirit). Oleene boils. Potassinm melts; vapor bath ends. Berger in vapor bath 13 min. Jorullo springs, S. AMERICA; MYNPOOREE, max t. Sands at S. Fernando, S. AMERICA, air lOl* Stearic and oleic acids (mixed) melt, BELBEIS, XGYPV Mutton suet melts; Cauterets spr. Kntakekaumene spr. 122 Styracine m. Stearine and cetine melt; myristic acid m.; elaat A. V. 3*38. Palmitic acid m. Bath springs, max. t; supposed depth 3,360 ft. *Lark. Bromine boils ; hot pump at Bath, dens. Br, V. 6'64. Elms Si)r. max. t King's bath at Bath, laurine m. Sol. ammonia boils 0*91. 112 Spermaceti melts ; Muscat eprings. ♦Duck, *guinea fowl, *raTen. "^Pigeon; PEKIN, max. t. ; Vichy apr. max. t C. fowl ; Cross bath at Bath. *Bird», lOS-*, lU". Sulpli. carbon boils. Coldblooded animals die. Temp, for incubation; elast. ether van. 30 inches "^Slieep and pig, owl ; pliosjihorus melts. 102 *■*!'*• "^"S" P"»t» artificial mcubation. * '*Animal8, man, max- t ; ox, infant child. ^Squirrel, rat, cat, jackal, panther. *Bat, liare, tiger, horse, elephant; elast A. V, I'M. Warm bath ends, vapor batli commences. '*Temp. man, kite (birds). Blood heat, hedgehog, dnrmou.<>e. [V. a^flg. Tepid bath ends, warm bath begins; Ether boils 0*734; dena. Oil of roses melts ; cocoic acid m. ^ PUTREFACTION rapid. Old palm oil m. 92 VALENCIANA MINE, MEXICO; Grenelle well, 1,794 ft. Elast A. V. 1-36; Pold ice mine. Tallow melts. ACETOUS FERMENTATION, PETERS B URG, max. t ; oil nutmegs m. Kaisareyeh. ASIA MINOR. 4,200 ft. el. Tepid bath begins. Cacao butter m. [1498 fV *Tortoise, Cornish mines, Buxton Spa, DALCOATH MINM "Serpents, SEA EQUATOR, 83-7. on Nitrous acid 1-42 boils; Buxton bath, ALGIERS, s. t •S^ EQUATOR, m. t 81-6 1 *oy9ter, snail (Tropics). Phosphorus luminous in pure oxygen; NAPLES, s. t Prussic acid boils 0-69, [£|, A. ▼. 1 Prog, shark, flying fish, scorpion (Tropics). Insect!!, silk wo.-ms hatched, germination. Bristol Spa, temp., wasp. MEXICAN MINES 1,650 ft. deep; SYDNEY, a. t Glow worm, cricket ; PRUSSIAN MINES, 880 ft. Artesian well, GRENELLE, 1,300 ft. deep. 72 MONKWEARMOUTH MINE. 1,600 ft, deep. CENTIGRADE. REAUMUR. FAHRENHEIT. 20- SANTA CRUZ, TENERIFFE. Hypon. ether b. ; iodine vaporised. Elast. A. V. 0-731, Cotton tree; ALGIERS, m. t Gipps land, AUSTRALIA, MALTA, m. t. CAPE OF GOOD HOPE, FUNCHAL, m. t Elast A. V. 0*616. CultiTation of Tine ends, ENGLAND, m. b. t 63-6. TOULON, m. t Elast A. V.0-S2; ROME, NICE, m.t tflLTILLS, I. (max, t) NISMES, GENOA, LUCCA, m. t PERPIGNAN, MONTPELIER, m. t Waterford mines, 774 ft. dep. MARSEILLES, m. t LISBON, BOLOGNA, BORDEAUX. AIX, VENICE, m. t LYONS, VERONA, MILAN, m. t PAU, in. t LOWER EGYPT, w. t AMSTERDAM, PEKIN, NEW YORK, m. t m. t NANTES, ST. MALO, MALTA, w. t ; m. t BRUSSELS. PENZANCE, m t in Cultivation of vine begms, PARIS, LONDON, m. t ■"■"' Elast A. V. 0-37., S. O. 01. Salt nriines CRACOW, 730 ft. ; Muriatic acid, 40 at Liq, ) Sulphur, hyd. 17 at ; ammonia, 6*6 at ) EDINKURGH, BERLIN, DUBLIN, m. t INVERNESS, COPENHAGEN, m. t COVE CORK, w. t, m. t TORONTO, MONT PERDU, PYRENEES, II. -265 ft eL UPSAL, STOCKHOLM, QUEBEC, m. t CANADA, m. t E List A. V. 0-263. CHRISTIANIA, DRONTHEIM.m t Hybernation of animiils. PETERSBURG, m. t; Etna sum. 10.956 ft. el. KASAN, ni. t POLAR SEAS 360 ft deep. BERGEN, PADUA, COLUMBIA, r. w. t MOSCOW, m. t ; oils freere. ALTEN, NORWAY, m. t (Carbonic acid hq. 36 at), N.CAPE LAPLAND, LABRADOR, Elast A. V. 2 inclies, S. G. 005. CUMBERLAND, HO. N. A. m. t Eartli, YAKUTSK. 3.M) to 38-2 ft dep. CHIMBORAZO, 18,6fl0 ft el, MONT BLANC, if> fi'M ft. HIMALAYAS, 18,01)0 ft el. IRKUTSK, m. t SIBERIA, m. t. Earth YAKUTSK, 77 ft. dep AIR. m t POLAR SEA NOYA ZEMBLA, m, t, PORT ENTERPRISE, w, t Aniiyd. sulphitrous acid boils. Oil of turpentine freezes, JQ • LoTest natural temperature at YAKUTSK in Siberia. — 72=84'' below this scale. CENTIGRADE TO FAHRENHEIT. Above Ice. Between Ice and Zero. CXl'8+33. 33 (CXl'S). Below Zero. Cxt'S— 32. Water boile in vacuo, *crab. VINOUS FERMENTATION, butyrine melta, CAIRO WELL DURHAM COAL MINES, 'MfO ft. [310 ft. im^. Cocoa nut oil liquid, Matlock bath. Grotto del Cane. CORDILLERAS, ANDES, m. t ."i.OOO ft. el. Matlock springs, CUMBERLAND COAL MINES, 600 ft. SAXON MINES, 1,246 ft ; Bakewell spring*. [it- i MADEIRA, m. w. t; air centre of Atl. waters of the ScajBa» NAPLES, m. t Temp, for sick rooaxg. ^ DEEP MINES, EUROPE; sea bnuk of AguiUas. ■02 PARAMATTA, N. S. W. m. t ; ALGIERS, w, t ; aea Aaoras. Fluoric acid boils, anhyd. chlorine liqfd. 4 at Acetic add cryst ; Puy de Dome, 3,600 ft. CAIRO w. t. MINES OF BRITTANY 500 ft., BEKGEN •■ t *Trout, MEDITERRANEAN SEA 2,000 ft, decfk Vaucluse fountain, StiO ft el. Artesian well VIENNA, 200 ft. ; Hanwell,390 ft. Camphor floats, elast A. V. 44. PIC DU MIDI, 9,660 ft. ; JERSEY, m. t ■52 ^'' ^^ aniseed solid, muriatic ether boils. CLER.MONT, m. t ; Columbia r. m. t [beipae. ITALY, m. w. t ; VIENNA, m. t 60 6; PUTREFACTION Liq. ammon. boils, Sat at 32; STRASBURG, m. t WARSAW, BERNE, m. t [PRAGUE, GENEVA, aa. t TENERIFFE PEAK, 12,072 ft. el. ZURICH, GOTTINGEN, LABRADOR, s. t Sulphurous acid liqfd. 8 at ; protox. nit 50 at; Cyanogen, 30 at SEA EQUATOR, 3.400 ft deep. 4n DEEP SEA, common springs, HASTINGS, w. t ■*•* LAKE OF GENEVA, 1,0(»0 ft. deep ; ROME, w. t LAKE LUCERNE, fi.=S0 ft. deep ; *beetle, PAU, w. t St acid freeze.s; CARPATH. MOUNTAINS: mercury evap. CAPE HORN SURFACE OF SEA, max. density of water. EDINBURGH, w.t ENGLAND, m. w. t 37-8. [w. ^ Alcohol boils in vacuo; NOVA ZEMBLA s. t, SHETLAND Fixed oils freeze; SOUTH SEA. 1-J,420 ft. deep. CAPE HORN SEA, 6,400 ft deep. Mount Argaeus, ASIA MINOR, 10,300 ft. eL .32 ICE, chlor wr. freexee, sc. ad. 3rd., hydr. freei£t I'OLAK SEA, 3,300 ft. deep; earth YAKUTSK, 383 ft. deep. Milk freezes. CAKTHAGENA, SPAIN, w. t Salt water freezes, 1,0-26 ; vinegar freexes; formic acid freeew Earth YAKUTSK, 217 ft. deep. JUNGFRAU, summit, I2.72.i ft. Blood freezes, earth YAKUTSK, 119 ft. deep. Eliiin freezes, HECLA (Air) at summit, 6,110 ft. A ^22 O'' bergamot freezes. Oil cinnamon freezes, oleic acid (castor oil) frnaaw Wine IVeesea, Earth YAKUTSK, 60 ft, dep. GUI.FBOTHNIA AIR, m. w. t : Great Bear Lake, m t AIR -23,000 feet elevation above PARIS (at surface SVi. Salt water freezes, 1-104. ,„ RUSSIA, m. w.t • I* Prussic acid cryst 69 S. O. ALTEN, NORWAY, w. t N. POLE, m. t 13 below zero (calc). Mercury freezes. I 40" below zero, m. w. t.. at KOTi Ether Ik>iIb in vacuo. ) ZEMBLA AND YAKUTSE. Carbouic acid freezes 148" below zero. Lowest artificial cold 187" below zero. FAHRENHEIT TO CENTIGRADE. Above Ice. Between Ice and Zeio F-33 32-F 1-8 !•• Below Zero F+W ABBREVIATIONS. m. melts, m. t mean temperature, w, winter, a. eummpr. at. atmosphere, b, boils, v. rolatilized, liq. liqtiid, liqfd. liquefied. Ad. acid. max. maximum, min. minimum. Sol. solution, W. B. water boils, el. elevation. In reference to fusible alloys. B. Bismuth. T. tin. L. lead. pr. pressure, dep. dej)re88ion. I. Island. Vapr. Vapoc Elast Elasticity. Fluid. Fluidity. Alch, Alcohol, Turp. Turpentine, dens, aensity. In regard to places meaa temp, is implied where not expressly stated, r. river, spr, spring, fr, freezes, A. V, Aqueous vapor, d. ▼ density of vapor. S. G, specific gravity. The Elasticity of Vapors is given in inches of Mercuiy. TEMPERATURES ABOVE THE SCALE. Tin and Cadmium m. 442«». Tempered Steel (straw color) 460°. Sc. ad. 1-78 b. 467o, Bismnth m. 476*. Tempered Steel (brown) 500° Fixed Oils b. SJO*. Tempered Steel (red and purple) 550". The same (blue) 600*. Leadm. 612*>. Sc. ad. 1-85 b, 648^ Mercury b. 602*. Zinc m. 680«». Gunpowder explodes 700®. Antimony m. 8I0», Red heat 980«». FKnt glass m, 1000^. Heat of common fire 1141o, Brass m. 1869® Silver m. 1873<». Copper m. 1996^. Gold m. 8016*. Cast Iron 2786*. Pure iron and Platina m. 3-380*. Wind furnace white heat 3300®. l( J» 84!^ THERMOMETER. II well as the mean range of the thermometer throughout the year, might easily find a place in all the common scales. When the length of the scale would admit of such an arrangement the mean temperatures of the principal cities and towns of Great Britain as well as of foreign climates, might be attached, with many interesting points in ani- mal and vegetable physiology. The extensive tables on temperature, collected and arranged by Sir James Clark, in hia excellent treatise on Climate, would here serve as a useful guide. It will be seen that the table now for the first time published, ranges from 12*^ to Z*I4P Fahr., from— 11° to -j- 190° Centigrade, and from -9° to -j- 162'^ Reaumur. It might have been extended, but this, it was considered, would have rendered it of very inconvenient size ; and besides, the range here selected comprises all the most remark- able phenomena connected with heat The more important facts relating to tempera- ture above and below this range, will be found inserted in distinct paragraphs, on the table, with formula for the conversion of the degrees of Centigrade into those of Fah- renheit, and vice versa. It will be only necessanr to state generally those facts which the table is intended to illustrate. They will be found arranged opposite to their respective degrees, either on the Centigrade or Fahrenheit side, according to the space afforded. Some points have been necessarily omitted, in order not to render the table confused. Thus it has been impossible to introduce all the maxima and minima of temperature in respect to climate, owing to the spaces being already occupied, but a selection hae been made of some of the most important of these. The facts connected with tempera- ture, placed on the scale, may be arranged under the heads of Climatology, Physical Geography, Chemistry, and Physiology. Climatology. 1. The mean temperatures of the principal countries, towns, and cities in the world, with the maxima and minima, as well as the mean summer and winter temperature of some of the most important localities. 2. The maximum degrees of heat, and the minimum degrees of cold, observed on the surface of the globe, including the accumulated temperatures of air at Edinbui^h and Geneva. , Physical Geography. 1. The temperature of the atmosphere, as observed on the summits of the principal mountains of the Old and New World, with the respective elevation attached — at the sea level in various latitudes, from the Arctic to the An- tartic seas, as well as in deep mines and other excavations in Europe and America. 2. The temperature of the ocean at the surface, and at various depths 12,420 feet, including the temperature of the Polar Seas, of the Mediterranean, Atlantic, and Pacific^ with the temperature of the Gulf stream. 8. The temperature of the waters of lakes and rivers at various depths, with the re- spective fathomings attached. 4. The temperature of the strata of the earth at various depths, observed in some of the deepest mines in the Old and New World. 6. The temperature of water raised in Artesian wells in Europe, from deptha varying from 250 to 1*794 feet. 6. T^e temperature of the principal thermal springs and baths observed in Europe, Africa, the West Indies, and South America. 7. The temperature at which water boils at all the elevated and inhabited spots in the world, including the summits of the mountains of Switzerland, South America, and Central Asia; the boiling point for all elevations up to 5416 feet, and for 1064 feet de- pression below the level of the sea. Chemistry. 1. The evaporating, boiling, fusing, melting, subliming, and congealing points of all solids and liquids in chemistry, from 12** to 374' Fahr., from — 11° to -|-190° Cent and from — 9 to -f 155° Reau., including the boiling points of the saturated solutions of numerous salts, and the melting points of a large number of alloya 2. The temperature for fermentation of various kinds, malting, putrefaction, etherifi* cation, and other chemical processes. . 3. The boiling points of alcohol and acids of various specific gravities, with the re- spective densities of the vapors. 4. The pressure or elastic force of the vapor of water, alcohol, oil of turpentine and "ether, at various temperatures. 6. The temperatures, with the corresponding pressures required for the liqnefactioB of the gases. 6. l!he temperature for the explosion and ignition of fulminating and combustible labstances. Physiology. 1. The maximum degrees of natural and artificial heat^ and minim n m degrees of cdd, borne bj man and animals. THERMOSTAT. 843 2. The temperature of the body in man, mammalia, birds, reptiles, fishes, and insects. '^ 3. The temperature at which hybernation takes' place in certain animals. 4. The temperature for the germination of seeds, incubation, the artificial hatching of the ova of birds, fishes and insects. 6. The temperature for the growth of the sugar-cane, date, indigo, cotton tree, and for the cultivation of the vine. 6. The temperature for warm, tepid, and vapor baths; the vapor baths of Russia and Finland. As the value of a table of this kind, depends less on the compiler than on the observers on whom he relies, I feel bound to state that I am chiefly indebted to the following authorities:— for Climatology and Physical Geography; to Humboldt,. Bonpland, Saussure, Boussingault, Rose, Ermann, Baer, Von Wrangell, Breislak, Phipps, Scoresby, Franklin, Parry, Back, Ross, Pachtusoff, Zivolka, Cordier, Gay- Lussae, Pouillet, Biot, Arago, Bertrand, Desfontainos, Gerard, Lhotsky, Schomburgk, Davidson, Forbes, Brewster, D'Abbadie, Moore, and Beke;— for Chemistry and Physi- ology; to Berzelius, Dumas, Mitscherlich, Gaultier de Claubry, Peligot, Davy, Fara- day, Ure, Brande, Graham, Turner, Dr. Davy, and Liebig. In respect to the department of Physical Geography, I am much indebted to the foreign correspondence of the Athenaeum. ^ Many of the facts I was enabled to collect or verify by personal observation during a iourney through France, Italy, and Switzerland. Some of the chemical phenomena have also been derived from direct experiment It is very probable that a few of the temperatures, in each department, will be found to differ from those given in some works on Chemistry ; and, on this point, I have one remark to make, namely, that the greatest discrepancies will often be found among respectable authorities in regard to temperature. It is impossible here to enter into the causes of these discrepancies. I have invariably acted on the principle of selecting the best authorities ; and where these differed, I have endeavored to arrive at an approximation to the truth by experiment, or where this was impossible, by seeking for corroborative circumstances. A large number of observations, made by travellers, I have been obliged to reject, in some instances, owing to the omission or confusion of the -}- and — signs ; and in others, owing to the observers having omitted to state what thermometers they employed. During the researches into which the compilation of this table has led me — occupying as it has done the occasional leisure of four years— mj^ mind has been strongly impressed with the benefits which would accrue to science, if the philosophers of Europe would agree to employ only one scale, with small degrees, and so adjusted as to render entirely un- necessary the use of the -|- and — signs. THERMOSTAT, is the name of an apparatus for regulating temperature, in va- porization, distillation, heating baths or hothouses, and ventilating apartments, Ac.; for which I obtained a patent in the year 1881.* It operates upon the physical principle, that when two thin metallic bars of different expansi- bilities are riveted or soldered f&cewise together, any change of temperature in them will cause a sensible movement of flexure in the compound bar, to one side or other; which movement may be made to operate, by the intervention of levers, Ac, in any desired degree, upon valves, stopcocks, stove-registers, air-ventilators, Ac. ; so as to regu- late the temperature of the media in which the said compound bars are placed. Two long rulers, one of steel, and one of hard hammered brassy riveted together, answer very well; the object being not simply to indicate, but to control or modify temperature. The following diagrams will illustrate a few out of the numerous appli- cations of this instrument :— i%. 1448 a, 6, is a single thermostatic bar, consisting of two or more bars or rulers of differently expansible solids (of which, in certain cases, wood may be one): these bars or rulers are firmly riveted or soldered together, face to face. One end of the compound bar is fixed . . ... _, ^ , y^y ^^^^ at a, to the interior of the containinfir Cistern, boiler, or apartments, almb, whereof the temperature has to be regulate^ 844 THERMOSTAT. THIMBLE. 845 , 1 1451 and the other end of the compound bar at 6, is left free to move down toward e, hy the flexure which will take place when its temperature is raised. The end 6, is connected by a link, h d, with a lever d e, which is moved by the flexure into the dotted position 6 g, causing the turning-valve, air-ventilator, or re- gister, o n, to revolve with a corresponding angular motion, whereby the lever will raise the equipoised slide-damper k t, which is suspended by a link from the end e, of the lever e cl, into the position k h. Thus a hothouse or a water-bath may have its temperature regulated by the contemporaneous admission of warm, and dischai^e ->f cold air, or water. Fig. 1449 a 6 c is a thermostatic hoop, immersed horizontally beneath the surface of the water-bath of a still. The hoop is fixed at a, and the two ends 6, c, are connected by two links hd,cd, with a straight sliding rod d h, to which the hoop will give an endwiso motion, when its temperature is altered ; e, is an adjusting screw-nut on the rod d h, for setting the lever / g, which is fixed on the axis of the turning-valve or cock /, at any desired position, so that the valve may be opened or shut at any desired temperature, corresponding to the widening of the points b, c, and the consentaneous retraction of the point d, toward the circumference a 6 c of the hoop, g h, is an arc graduated by a thermometer, after the screw-piece e has been adjusted. Through a hole at h, the guide- rod passes; «, is the cold-water cistern ; ifk, the pipe to admit cold water; I, the over- flow pipe, at which the excess of hot water runs ofi; Mg. 1450 shows a pair of thermostatic bars, bolted fast together at the ends a. The free ends 6, c, are of unequal lengths, so as to act by the cross links d, f, on the stopcock e. The links are jointed to the handle of the turning plug of the cock, on opposite sides of its centre ; whereby that plug will be turned round in proportion to the widening of the points be. h g a the pipe communicating with the stopcock. Suppose that for certain purposes in pharmacy, dyeing, or any other chemical art, a water-bath is required to be maintained steadily at a temperature of 150° F. ; let the combined thermostatic bars, hinged together at e, /, fig. 1451, be placed in the bath, be tween the outer and inner vessels a, 6, c, d, being bolted fast to the inner vessel at g ; and have their sliding rod k, connected by a link with a lever fixed upon the turning plug of the stop-cock t, which introduces cold water from a cistern m, through a pipe m, i, n, into the bottom part of the bath. The length of the link must be so adjusted that the flexure of the bars, when they are at a temperature of 150°, will open the said stop- cock, and admit cold water to pass into the bottom of the bath through the pipe i, n, whereby hot water will be displaced at the top of the bath through an open overflow- pipe at q. An oil bath may be regulated on the same plan ; the hot oil overflowing from 5, into a refrigeratory worm, from which it may be restored to the cistern m. When a water bath is heated by the distribution of a tortuous steam pipe through it, as i, n, o^p, it will be necessary to connect the link of the thermostatic bars with the lever of the turning plug of the steam-cock, or of the throttle valve i, in order that the bars, by their flexure, may shut or open the steam passage more or less, according as the temperature of the water in the bath shall tend more or less to deviate from the pitch to which the apparatus has been adjusted. The water of the condensed steam will pass off from the sloping winding-pipe i, n, o, p, through the sloping orifice p, A saline, acid, or alkaline bath has a boiling temperature proportional to its degree of concentration, and may therefore have its heat regulated by immersing a thermostat in it, and connecting the working part of the instrument with a stop-cock t, which will admit water to dilute the bath whenever by evaporation it has become concen- trated, and has acquired a higher boiling point. The space for the bath, between the outer and inner pans, should communicate by one pipe with the water-cistern m ; and by another pipe, with a safety cistern r, into which the bath may be allowed to overflow du- ring any sudden excess of ebullition. Mg. 1454 is a thermostatic apparatus, composed of three pairs of bars, d, d, d, which are represented in a state of flexure by heat ; but they become nearly straight and parallel when cold, a 6 c is a guide rod, fixed at one end by an adjusting screw e, in the strong frame / «, having deep guide grooves at the sides. / g, is the working-rod, which moves endways when the bars d, d, d, operate by heat or cold. A square re- gister-plate h g, may be affixed to the rod f g, so as to be removed backward and for- 1453 1454 ward thereby, according to the variations of temperature; or the rod / g, may cause the circular turning air-register, i, to re- volve by rack and wheel-work, or by a chain and pulley. The register-plate h g, or turning register t, is situated at the ceiling or upper part of the chamber, and serves to let out hot air. k, is a pulley, over which a cord runs to raise or lower a hot-air register I, which may be situated near the floor of the apartment or hot-house, to admit hot air into the room, r, is a milled head, for adjusting the thermostat, by means of the screw at e, in order that it may regulate the temperature to any degree. Fig. 1455 represents a chimney, furnished with a pyrostat a b c, acting by the links o, d, e, c, on a damper / h g. The more supposed to be on the outside. The plan? Ttt'irp:Ula^ till'^hlsTar 7trmVerurt:"^'^ ''''' ^'^ ^^^^^^^ '' '"^^ ^-"^^^ ^'^^^^^^^ criTyt in^eJ^: Fig. 1453 represents a circular turning register, such as is used for a stove or stove- grate, or lor ventjlatmg apartments ; it is furnished with a series of spiral Th'ermosS^Tc bars e^ch bar being fixed fast at the circumference of the circle 6, c, of the fixeT nlate "55 of the air-register ; and all the bars act in concert at the centre a, of the LTh nl ^* ?f '^^- '^^'T' ^^ ^^^'" ^"^^ ^""S inserted between the nt 1 . K™^^^ ^1"'^"' ''' ^y bemg jointed to the central part of the turn- ing plate by small pms. ^J'vh ^.^^2 represents another arrangement of my thermostatic apparatus applied to a circular turning register, like the preceding, for veXS bv meT.'of 7rvT' «^^r P-"d b-r« are appfied so as7o actrconce^ by means of the links a c,b c, on the opposite ends of a short lever which IS fixed on the central part of the turning plate of the air-reS The Z\lX^LTZf '"' «^-\^-tened to the circ^flrence^o? the faxed plate of the turning register, by two sliding rods ad, be, which are furnished with adjusting screws. Their motion or flexure is Trwis^ muted by the links a c, and b c, to the turning plate, about its centre^o^ tnnr. ,^ the purpose of shutting or opening the venUkting* sectorial a^Jres more or less, according to the temperature of the air which surrounds he thermosteS urning register. By adjusting the screws a rf, and 6 c, the turninrre%sterTs^^^^ to close all its apertures at any desired degree of temperature : but whenever the ^?l! THIMRrT?^'''"'"' '"f "^^'^2,^'^- <^«'nP<'»nd bars will open t^e apertures IHIMBLE (-De a coudre.Fv.i Fineerhut ( Untrprhnt^ r^r.J.\ • ^ "Hciiuiej*. metallic cone deviating little froi a ^^Ser,^^^^^^^^^^^^ middt fiT efofr ^'Cc::z'i^s't7:ii^ : r «-?<>' "^^ through uoth or leather, in the act of sewin^ Th^? lim! ff^ readily and safely two ways; either with a pitted round erdTr^'withoit one he l^n'"' »^,S'^i«"ed in thimble, being employed by tailors, uphols erers and Uner^lvlp^ ""^^^ '^.1 ^P^"" The following ingenious process for makinl S pJllnf ? • V ^P^^^^"?' ^^ needle-men, MM. Rouy and'Berthier,Tf Paris ha h^^^^^^^ '}^ contrivance of Sheet-iron, one twenty-fourth of an inoh tM^l ?»ch celebrated, and very successful. to the intended size^ thrthYmbles T^e^e 'Jrin? '"'"^ ^^"P/» o^ dimensions suited whereby they are cut into LcsTrb^ut 2lLS.?^ .^^''^ ^"^"'' * P^^^h-press, Each strip contains one dozen of these Inkr^f 'l^'f '''^''^'' ^^ * ^*«- hot, and to lay them on a mand/ilnfcely fitted* tolhei i'e '"rh'/w 'l °^"''' '""'"^ '.'^' the middle of each with a round-faced Lnoh«hn„t/h 1\ ^^^ workman now strikes sinks it into the concavity of the first manSril He ^l /'^"f '• ^'' ^""^''^ *"^ ^^" other mandril, which has five hollows ^f^nrL.^^^ - *'^"'^"/ *' successively to an- it into them, brings it to the proper Iha^!^ mcreasmg depth; and, by striking A second workman takes this rude thimble stiVVc-t ;n fK.» «i. i /-l- . .. . to polish it within, then turns it outside maVK the .r^ ? "»f ""^^llf '^^^^' '" ""'^ united to the surface of fhe i.^^^ by re^l^TLtf i? tf^Z'l^^^J^ 846 THREAD MANUFACTURE. dril. A gold fillet is applied to the outside, in an annular space turned to receive it» >»eing fixed, by pressure at the edges, into a minute groove formed on the lathe. Thimbles are made in this country by means of moulds in the stamping-machine. See Stamping of Metals. THORINA is a primitive earth, with a metallic basis, discovered in 1828, by Ber- xelius. It was extracted from the mineral thorite, of which it constitutes 58 per cent., and where it is associated with the oxydes of iron, lead, manganese, tin, and uranium, besides earths and alkalis, in all 12 substances. Pure thorina is a white powder, without taste, smell, or alkaline reaction on litmus. When dried and calcined, it is not affected ly either the nitric or muriatic acid. It may be fused with borax into a transparent glass, but not with potash or soda. Fresh precipitated thorina is a hydrate, which dis- solves readily in the above acids, as well as in solutions of the carbonates of potash, soda, and ammonia, but not in these alkalis in a pure state. This earth consists of 74-5 parts of the metal thorinum, combined with 100 of oxygen. Its hydrate contains one equiva- lent prime of water. It is hitherto merely a chemical curiosity, remarkable chiefly for a density of 9-402, far greater than that of all the earths, and even of copper. THREAD MANUFACTURE. The doubling and twisting of cotton or linen yarn into a compact thread, for weaving bobbinet, or for sewing garments, is performed by a machine resembling the throstle of the cotton-spinner. Fig. 1138 shows the thread-frame in a transverse section, perpendicular to its length, a, is the strong framing of cast-iron ; 6, is the creel, or shelf, in which the bobbins of yam I, I, are set loosely upon their respective skewers, along the whole line of the machine, their lowei ends turning in oiled steps, and their upper in wire eyes ; c, is a glass rod, across which the yarn runs as it is unwound ; d, d, are oblong narrow troughs, lined with lead, and filled with water, for moistening the thread during its torsion ; the threads being made to pass through eyes at the bottom of the fork e, which has an upright stem for lifting it out, without wetting the fingers, when anything goes amiss ; /, /, are the pressing rollers, the under one g, being of smooth iron, and the upper one h, of box-wood; the former extends from end to end of the frame, in lengths comprehending 18 threads, which are joined by square pieces, as in the drawing-rollers of the mule-jenny. The necks of the under rollers are supported, at the ends and the middle, by the standards % secured to square bases j, both made of cast iron. The upper cylinder has an iron axis, and is formed of as many rollers as there are threads; each roller being kept in its place upon the lower one by the guides k, whose verticle slots receive the ends of the axes. The yarn delivered by the bobbin /, glides over the rod c, and descends into the trough d e, where it gets wetted : on emerging, it goes along the bottom of the roller g, turns up, so as to pass between it and h, then turns round the top of A, and finally proceeds obliquely downward, to be wound upon the bobbin m, after traversing the guide-eye n. These guides are fixed to the end of a plate which may be turned up by a hinge-joint at 0, to make room for the bobbins to be changed. There are three distinct simultaneous movements to be considered in this machine 1, that of the rollers, or rather of the under roller, for the upper one revolves merely by friction ; 2, that of the spindles w, «'; 3, the up-and-down motion of the bobbins upon the spindles. The first of these motions is produced by means of toothed wheels, upon the right hand of the under set of rollers. The second motion, that of the spindles, is effected by the drum z, which extends the whole length of the frame, turning upon the shaft v, and communicating its rotary movement (derived from the steam pulley) to the whorl b' of the spmdles, by means of the endless band or cord a\ Each of these cords turns four spindles, two upon each side of the frame. They are kept in a proper state of tension by the weights e\ which act tangentially upon the circular arc This ore has been found in few countries in a workable quantity. Its principal locali- ties are, Cornwall Bohemia, Saxony, in Europe ; and Malacca and Banca, in Asia. Ihe tin-mines of the Malay peninsula lie between the 10th and 6th degree of south lati- tude ; and are most productive in the island of Junck-Ceylon, where they yield sometimes aoo tons per annum, which are sold at the rate of 48/. each. The ores are found in lar<-e caves near the surface ; and though actively mined for many centuries, still there is easy access to the unexhausted parts. The mines in the island of Banca, to the east of Smatra discovered in 1710, are said to have furnished, in some years, nearly 3500 tons of tin. Small quantities occur in Gallicia in Spain, in the department of Haute Vienne inlrance, andin the mountain chains of the Fichtel and Riesen^eburge in Germany. The columnar pieces of pyramidal tin-ore from Mexico and Chile, are products of stream- works. Small groups of black twin crystals have been lately discovered in the albite rock of Chesterfield in Massachusetts. The Cornish ores occur— 1 in small strata or veins, or in masses ; 2. in stockwerks, or congeries of small veins ; 3. m large veins ; 4. disseminated in alluvial deposites. The stanniferous small veins, or thin flat masses, though of small extent, are somt- Umes very numerous, mterposed between certain rocks, parallel to their beds, and zte commonly caUed Un-floors. The same name is occasionally given to stockwerks. In 849 Sh-tv six flthorit b!^ fi "f^,^^ .^"^" ^^""^ ''' the killas (primitive schistose rock), Shi .nnr-P h , ^""^ ^^'^ -^""^^ ""^ ^^^ ^^^ 5 it is about a foot and a half thick, and occu' cinnexLn TeLeP^^^^^^^^ principal vein and its ramification ; but there seems to be no connexion between iha Jloor and the great vein. •Z^tnThr^ .***'*'"*' /" ^'^"^^^ ^"^ '^ ^he feldspar porphyry, called in ComwalJ. S^^ar%/!^.Lr'Tr''^^''°^'^'^^-^? *^^ granite, is Vthe'lin-mine of Carcli^ t^^ni.J'fu \-^-^^ ''''''■^^ ^^^ ^^^"^d 0" i*! the open air, in a friable granite, con! Sinv ?S'r ^'''''''^'^'f V"to kaolin, or china cla^ which is traversed^by a%reat S/eadoni InLT'^'f.fTl'^^^'''''^ ^'^^^^"^ ^"^ ^ ^^''^^ ^'^^-^tone, that form black ra dy iceeds fi inlr ""■ ^^e light-gray granite. The thickness of Ihese little veins mich less Sol nrf^' ^"'^^'^^^"- ^he adhering solidified granite, and is occasionally mhcrs with fhP«J H^°\'"''"1^''^ ^^? ^"^ ^^'t' '^''th an almost vertical dip; degrees. direction, incline to the south at an angle with the horizon of 70 mJn!fn?''5^''''"^//*'''u'\f J"^ ^'■^ '""*''' "'"^^ frequent in tfieelvan (porphyry), of which the mine of Trewidden-ball is a remarkable example. It is worked among flattened masses anS^'STno?' '''''''' ^'^l^' ^''^' ''^ '' ^^^ -st-north-east V a consid^rS gkche/wh.Vh Z ^*^^""^^" '""^^ ^^^"«' 7*^y»"? i" thickness from half an inch to 8 or eitrtL^tect^VoT^^^^^^^^^ interrupted, that it is difficult to determine of Co Jn w Jl 17t"i? ^'T' P^talliferous veins are not equally distributed over the surface 01 Cornwall and the adjoining part of Devonshire; but are grouped into three districts • namely 1. in the south-west of Cornwall, beyond Truro; 2. inhHeic^h^^^^^^ St. AusUe ; and 3. In the neighborhood of Tavistock in D^vonshL. ""^'^^^'^"^ ^^ «hnn JL P-^ f-'"''^ •' ^^- ^^^ t^^ "*^^^'t, and the best explored. The formation most abnndan m m mines is principally granitic; whilst tha of the copper iSnes ?s m^t fiequently schistose or killas; though with numerous exceptions. The great tiiv«^s are the mos ancient metalliferous veins in Cornwall ; yet they are not aU orone for^f buTi^rT '" T ^"^^^?' ^y^^^°^^- Their direction is, hUever, nearly the s^e" ollr tT "^f.^^"" ^? 1°'^^'*^' ^^^ "«^^^' «"d ^ll^ers towards the south. The firstTe tip on ^V- K '!'^"^ ' [""' ^" ^" '^^ °^*»^« ^^^^^ t^^ese two sets of vein; are assodltS of ^ip^'I?""^"*' • mines, the two systems of tin veins are both intersected by the oldest of the copper veins; indicating the prior existence of the tin veins. In )g! 1457 ' *^' ^ marks the first system of tin veins ; c, the second ; and d, the east and west copper veins. Some of these tin veins, as at Poldice, have been traced over an extent of two miles ; and they vary in thickness from a small fraction of an inch to several feet, the average width being from 2 to 4 feet; though this does not continue uniform for any length, as these veins are subject to continual narrowings and expansions. The gangue is quartz chlorite, tourmaline, and sometimes decomposed A aij • 1 ^' . granite and fluor spar. trntpr ?c Z • • 1 *"*^ ^*- ^^^^^^ 5 w^ere they are called stream-works • because wat^er IS the prmcipal agent employed to sepamte the metalUc oxyde froTthe'sand and Dla^eVatini"?rnL^il"^/^' in Saxony (fig. 1458, which is a vertical projection in a tte wortoea zu,ater,or ambiguou,. In ,620, the mini w^wo Jd by 21 indSeS companies in a most irregular manner, whereby it was damaged toadepihof 170^^ hja dreadful downfall of the roofs. This happened on a Sunday, providentially'wh^X pious mmers were all at church. The depth of this abyss, mwked by the cimTun. 850 TIN. ft, I, I, is 66 fathoms ; but the devastation is manifest to a depth of 95 fathoms below thai tJuyCy and 35 fathoms below the actual workings, represented at the bottom of the shaft under b. The parts excavated are shaded black in the figure. There are two masses of ore, one under the shaft B, and another under the shaft c ; which at the levels 5 and 10 are in communication, but not at 6, 7. There is a direct descent from 8 to 9. The deposites are by no means in one vertical plane, but at a consider- able horizontal distance from each other, a is the de- scending shaft ; B is tlie extraction shaft, near the mouth of which there is a water-wheel; c is another extraction shaft, worked also by means of a water-wheel, a and c are furnished with ladders, but for b the ladders are placed in an accessory shaft b' j under d a shaft is sunk for pumping out the water, by means of an hydraulic wheel at D ; E is the gallery or drift for admitting the water which drives the wheels. This falls 300 feet, and ought to be applied to a water-pressure engine, instead of the paddles of a wheel. At d is the gallery of dis- charge for the waters, which serves also to ventilate the mine, being cut to the day, through 936 toises of syenitic ^ porphyry and gneiss. J is a great vaulted excavation. The mine has 13 stages of galleries, of which 11 serve for extracting the ore; 1 is the mill-course; the rest are marked with the numbers 2, 3, 4, &c. ; each having besides a characteristic German name. The rare mineral called topaz pycnite is found in this mine, above 10, between the shafts c and d. The only rule observed in taking ore from this mine has been to work as much out of each of these levels as is possible, without endangering the super- incumbent or collateral galleries; on which account many pillars are constructed to support the roofs. The mine yields annually 1600 quintals (Leipzick) of tin, being four fifths of the whole furnished by the district of Allenberg ; to produce which, 400,000 quintals of ore are raised. 1000 parts of the rock yield 8 of concentrated schlich, equivalent to only 4 of metal ; being only 1 in 250 parts. Bnt the most extensive and productive stream-works are those of Pentowan, near St. Austle. Fig. 1459 represents a vertical section of the Pentowan mine, taken from the stream-uo)kf Happy Union. A vast excavation, r, t, u, », has been hollowed out in TIN. 851 1459 the open air, in quest of the alluvial tin ore, T, which occurs here at an unusual depth, below the level of the strata r, s. Before getting at this deposite, several successive layers had to be sunk through j namely, 1, 2, 3 ; the gravel, containing in its middle a band of ochreous earth 2, or ferruginous clay ; 4, a black peat, per- fectly combustible, of a coarse texture, composed of reeds and woody fibres, ce- mented into a mass by a fine loam ; 5, coarse sea-sand, mingled with marine shells ; 6, a blackish marine mud, filled with shells. Below these the deposite of tin-stone occurs, including fragments of various size, of clay slate, flinty slate, quartz, iron ore, jasper ; in a word, of all the rocks and gangues to be met with in the surrounding territory, with the exception of granite. Among these fragments there occur, in rounded particles, » coarse quartzose sand, and the tin-stone, commonly in smal grains and crystals. Beneath the bed t, the clay slate occurs, called killas, (a, x, y,) which supports all the depositee of more recent formation. The systeii of mining is very simple. The successive beds, whose thickness is shown in the figure, are visibly cut out into steps or platforms. By a level or gallery of efflux, fc, the waters flow into the bottom of the well Z, m, which contains the drainage pumps; •nd these are put in action by a machine, ;, moved by a water-wheel. The extraction c/ the ore is effected by an inclined plane, i, cut out of one of the sides of the excavation, at an angle of about 45 degrees. At the lower end of this sloping pathway there is a fht^Vo^wul? ' ^''i^^ '^.' "PP^' ^"^ ^^ ^ horse-gm, for alternately raising and lowenng the two baskets of extraction on the pathway t. g«u«iuwcnng ^^nt"lAl '"^^'"'"^^ P^^."li*' ''"^ '" *^s mechanical preparation or dressing, on ac hft ^''''"'' '^ ^"''^^" °^^^^' ^^"" '^^'^> ^' ^^ h»^« stated, the s^ieam tS niniVk^ the mine tin is for the most part extremely dispersed through the ganffue it IZ^LT^ICLt^^^Z^ ^"^ «"^ ^^'"' '" -'- "•« -WicXS' i' is lesAnt"!^ ™f^!r ■°^'i°"°T'' """^. «"*'" """> *■>«' <"■ ■»««» o'her metallic ores, it ^^'in^ytzn^^a^s^"'''''' "^ '''-''' - -^ '° •« -""^'-'^ ^ 3. As the peroxyde of tin is not afifected by a moderate heat it mav be exno^nl tn p«1 We may therefore conclude, that tin ore should be first of all pounded verv fine in the foil: ^^''''''''S the ore.— This is usually done at the mouth of the gallery of efflux bv a-i- r;i* f''''l}''S---The ore thus cleaned, is sorted on the grate, into four heaps : 1. stones rich m tin; 2. s ones containing both tin and copper ore; 3. copper ore- 4 senile pieces, composed ma great measure of stony gangue with iroi and arsenical pyrites la WheVresen^Thp'r ^' ^^^^PP- ^^ t|ie seco^kd 'and third heaps are obvtuTaLnu fra^m^en^are'^orte'drer "' " '"'^" "^^ ^"^"^^ ^'^^^^ "^^^ ^ -'^^^^^ -^ the 3. Stumping.— The stanniferous fragments (No. 1) are stamped into a sand of greater or less fineness, according to the dissemination of the tin-stone in he gan^c TheT- termination of the size of the sand is an object of great importance ItTreVulafed bv a copper plate pierced with small holes, through which every thing from the s^a^nin/ Several years ago, all the stamp-mills were driven by water-wheels which limited the quantity of ore that could be worked to the hydraulic power of iKre^m or water^^^^^^ but since the steam engine has been applied to this purpose, thrLnualpr^rt of tii has been greatly increased. On the mine of Huel Vor, there are "hree ste^ eneinS appropriated to the stamping-mills. Their force is 25 horses at least? O^of Sese llLrJni • \ The weight of these pestles varies from 370 to 387 pounds ; and they generally rise through a space of 10| inches. The machine called south stamvs thl strongest of the three, gives I7| blows in the minute, each pestle beinrMedtTc; ^^^^^ ft^'nL'''"'''il?'K ^'fT- r '^^^ '"'^"^ '^^^^' «^ this ^iU has a power Sf 25 hordes and itamp-rx!" "^"^" "^ '°"^' ^" '^' °^"'^'^- T^^^^ P^^^^^ Constitute a Se^, or Washing and stamping 0/ tin ores at Polgooth, near St. jSustle.-The stamps or pesUes 1460 1.^5 "'"''^^ ^ '''''^J ^y ^^ i" the square : they carry lifting bars 6, secured iTmn^nr"^'" "^'^^^ ,?.^ " ^'^' "^ ^^«"> «"d ^^cy terminate belowTa lump of cast iron a, called the head, which is fastened to them by a taU and weighs about 2| cwts The shank of the pestle is strengthened wiTh ZJrT.', '^ ^F"^"&/S^^ft communicates motion to the stamps by cams stuck round its circumference, so arranged that the second falls while the fin r^ 'i^'n ^^r^V^' are uplifted. There are 4 cams on one p^riphei;! and the shaft makes 7 turns in the minute. Each stamp, therefore, givTs lle^ttZr\TT «»\f^"V^ro«gh a space of 7i inches. The sfiLp chest s open behind so that the ore slips away under the pestles, by its trti^"^ '^- r^r^ ^^^T ^^^^ '^^ ^^^^^ «f ^^ter. The Wtom ol I 1 Pnii- ^ ^TT u^ '^'"P^^ °'*^^- With 6 batteries of 6 pesUes each, at A P«W»ce, near Redruth, 120 bags of ore are stamped in 12 hours ; each bag ' ' feTaTl6fcfbi;rrher ^"^ measuring altogethe; 352 cubil The openings in the front sides of the troughs are neariv ei«»ht inches hv rpvph nnrl . S ^^^y.^f "^^ ^^^^ ^l T'^ f--e, which b closed wih sK i ^nS^ w' th al^ut dels Jlc'^rf ^''^r '> ^T^- '""^'.^'.'5^' ^^^"S "*"«^«^ ^'thin. The ore7« issuing wS • I ^^^ V" ^^/ ^''^ ^^'"1' ^"^ '^^ ^^^^^« i« the following basins. The rough S n k?n!? ^'' f 'm ^'^^; P/^' f ^^; *"^ ^" tossing.tubs ; the slimes in tru'nks, and n? on a kind of twin tables, called racks. Into the tossing4ub, or dolly, fig. 1461, the stamS ed ore is thrown, along with a certain quantity of water, 'and a worLan s ti« it SSJl \l 852 TIN. I ^^W^^^^^^5^^»^m^WM?5^^^ "With an iron shovel for three or four minutes. He then removes a little of the water with a handled pitcher, and strikes the sides of the tub for 8 or 10 minutes with a hammer, which hastens the subsidence of the denser parts. The water is next poured off by inclining the tub to one side. In one operation of this kind, four distinct strata of the ores may be procured, as indicated by the lines a b, c d, e f g,hiky in the figure. The portion b is to be washed again in the trunking^x, figs. 1462, 1463 ; b is to be washed upon the German chests or racks, fig, 1464 ; c, the most considerable, js put aside, as schlich fit for the market ; d, forming a nucleus in the centre of the tub, is to be passed through sieves of copper wire, having 18 meshes in the square inch. This , „ , . . . Prtxluct thus affords a portion D', which passes through the sieve, and d which remams upon it ; the latter is sometimes thrown away, and at others is loniTrou-h" °P^''***®" ""^^^^ the He, viz., a washing upon the sloping bottom of a The slimes are freed from the lighter mud in the tiunking-box, /iff*. 1462,1463: which IS from 7 to 8 feet long. Being accumulated at m, the workmf n pushes them _^ ^ back with a shovel from a towards b. The metallic portion is carried off, and deposited by the stream of water upon the table ; but the earthy matters are floated along into a basin beyond it. The product collected in the chest is di- vided into two portions; the one of which is washed once, and the other twice, upon the rack, fig. 1464. Thii is composed of a frame c, which carries a sloping board or table, susceptible of turning round to the right or left upon two pivots, K, K. The head of the table is the inclined plane t. A small ^P . ,, - ,,.,„,... board p, which is attached by a band 01 leather l, forms the communication with the lower table c, whose slope is generally 5 inches m its whole length of 9 feet; but this may vary with the natire of the ore, bemg somewhat less when it is finely pulverized. The ore is thrown upon t, in small portions of 20 or 25 lbs. A woman spreads it with a rake, while a stream of water sweeps a part of it upon the table, where it gets washed. The fine mud falls through a cross slit near the lower end. After working for a few minutP*! «wi7T>I ZTT "^^^^^ ^^^^ ^ ^^^^^ ^* turns the t^hle ronldTs ^Tltl^tnf ''k''^. '"""^ 1°^"'^"^ ""^' ^^^ ^P^^^^ive is in B ; an impure schich^n ^'\^ S ^"^^^^ '' '"^° '^^ ^^^^^^ ^e^«^- The mud schlich fit for rSing in B- ' "''''' ^^ ""^^^"^ *^*^ "P°" *^^ ^""'^ ' ^""^^ ^Jhe slope of the raVtabie for washing the roasted tin ore, is Tf inches in the nine rop'eT^iS'ir^r^e' to\f SStd'^;^^^^^^^ ''T' ^'^ ^ ^^-^ ^^ - -'^^-^ A trap bling opened in t^e sMe of T. - l'^^ T' ^^^^^'^^^ «^«^^ in ;?g. 1465. It passes directly between thPtJn ^^,.^*S°'^' ^he ore falls into the hopper t, whence receives a see L mot?on h^^^^^^ "^^^ ^P<>^ '^^ sieve i, which TIN. 853 receives a seesaw motion hnr.Vnn7oiT;,T ' ' r* , "^^' "P®^ '^® sieve d, which upright turning-shar Ve fine/ .S^.^^ °lf^^ «^ i^« '^ ^> ^nd the crank of the forms the heap 8. tL coarser^^^^^^ ""^^"^^ P«^^^« ^^^^^^ that sieve, between the cyuJrT ^T^Zo^TZ:" llvef anT/ *'^ t^'' °' ^^A^^^^^' ^^^ '^ and s" of unsifted, ore ' ^"" * ^^^^r level, and forms the second heap s' of sifted, fin^e'ss'.°'?4^S^^ rr^^> ''^ p'^r ^^^^ -^ °^^^^ »- limps from the wagons. ' ^ ^^ uppermost hopper t, along with tht The diameter and length of the under rolls (see fig. 1466) are each 16 incnca. • 6, is the square end of the gudgeon t, which prevents the shaft shifting laterally on of its place. The di- ameter of the upper rolls is 18 inches, but their length is the same. Both are made of white cast iron, chilled or case-harden- ed by being cast in iron moulds instead of sand; and they last a month, at least, when of good quality. They make from 10 to 15 turns in a minute, ac- cording to the hard- ness of the ores of tin or copper; and can grind about 50 tons of rich copper ore in 12 hours ; but less of the poorer sort. * The next process is the calcination in the burning-house; which includes 1466 several reverberatory furnaces. At the mine of Poldice, they are 4 or 5 yards long, by from 2§ to 3 yards wide. Their hearth is hori- zontal ; the elevation, about 26 inches high near the fireplace, sinks slightly towards the chimney. There is but one opening, which is in the front; it is closed by a plate-iron door, turning on hinges. Above the door there is a chimney, to let the sulphurous and arsenical vapors fly off, which escape out of the hearth, without annoying the workmen. This chimney leads to horizontal flues, in which the arsenious acid is condensed. Six hundred weights of ore are introduced; the calcination of which takes from 12 to 18 hours, according to the quantity of pyrites contained in the ore. At the beginning of the operation, a moderate heat is applied ; after which it is pushed to a dull red, and kept so during several hours. The door is shut ; the materials are stirred from time to time with an iron rake, to expose new surfaces, and prevent them from agglutinating or kerning, as the workmen say. The more pyrites is present, the more turning is neces- sary. Should the ore contain black oxyde of iron, it becomes peroxydized, and is then easily removed by a subsequent washing. Figs. 1467, 1468 represent the furnace employed at Altenberg, in Saxony, for roasting tin ores, a is the grate ; b, the sole of the roasting hearth ; c, an opening in the arched 1467 roof for introducing the dried schlich (the ground and elutriated ore) ; d, is the smoke-mantle or chimney-hood, at the end of the furnace, under which the workmen turn over the spread schlich, with long iron rods bent at their ends ; e, is the poison vent, which conducts the arsenical vapors to the poison chamber (gifthaus) of condensa- tion. When the ore is sufllciently calcined, as is shown by its ceasing to exhale vapors, it is taken out, and exposed for some days to the action of the air, which decomposes the sul- phurets, or changes them into sulphates. The ore is next put into a tub filled with water, stirred up with a wooden rake, and left to settle ; by which means the sulphate of copper that may have been formed, is dissolved out. After some time, this water is drawn off into a large tank, and its copper recovered by precipitation with pieces of old iron. In this way, almost all the copper contained in the tin ore is extracted. The calcined ore is sifted, and treated again on the racks, as above described. The pure schlich, called black tin, is sold under this name to the smelters ; and that which collects on the middle part of the inclined wash-tables, being much mixed with wolfram, is caJled mock lead. This is passed once more through the stamps, and washed; when it also is sold as bla^k tin. Stream tin is dressed by similar methods; 1. by washing in a trunking-box, of such iimensions that the workman stands upon it in thick boots, and makes a skilful ust ■■ai 854 TIN. TIN. 855 'l!il >f the rake; 2, by separating the larger conglomerate pebbles from the smaller pure jig? 910^1 if '^^""P'"^' ^""^ washing, on a kind of sleeping-table, . See Metallurgy, thI^"jL-^lS' ^^^°',^^^" and Devonshire are all reduced within the counties where fer nn?nJnrvf ' tv^ laws prohibit Uieir exportation out of them. Private interests suf- ter no injury from this prohibition ; because the vessels which bring the fuel from Wales, for smelting these or«, return to Swansea and Neath loaded with copper ores The smelting-works belong in general to individuals who possess "no tin mines, but who purchase at the cheapest rate the ores from the mining proprietors. Th7 ores are S'rn/h'Th^'?^/" '^'^' ^r^";^ ^^ "^''^^^ ^"^ ''' fineness? condition whrchth^y determine by the following mode of assay :-When a certain number of bags of ore, of nearly the same quality, are brought to the works, a small sample is taken frSm each bae four n'pr^^pt '7 """^ ^i'^^l* ^^-^ """^^^ °^ ^^'^ average ore are mixed wifhaboS fnrn J V P""*^ ^''.^^' P"* ^''^'^ *" **P^" ^^'"^^^^ cfucible, and heated in an air verv hn/whpTK *^"^A^^ mches square) till reduction takes place. As the furnace is W t11 ftr''^^''':i".''^'^'^^^ «"'^^^J i" about a quarte, of an o }a- ^^*^ ^^"^ ^^^'^^^ *^ P®"*"^ *"*o * "^ould, and what remains in the crucible IS pounded m a mortar, that the grains of tin may be added to the in^ot. T.ni oo™f ^^ 'i^u""^ imperfect in a chemical point of view, serves the smelter's pur- pose, as It affords him a similar result to what he would get on the sreat scale A more thplT' r"^. '/ '^^'^"'^ ^y !:"^^"- ^" ^ ""^'We lined with hard rammS charToal! the ore mixed with five per cent, of ground glass of borax. To the crucible a gentle hea hould be applied during the first hour, then a strong heat during the second hour! and lastly, an intense heat for a quarter of an hour. This process brings out from four o five per cent, more tm than the other ; but it has the inconvenience of reducing the iron should asTavT«l!f ho t^n !'^^^ subsequent solution in nitrie acid will be readily shown. This saSpkTi^ one day. '' "^^ ^^''' ^'''^'^^ '"^ '"^ ^ ^'"^^ "^^"^ The smelting of tin ores is effected by two difi*erent methods — In the first, a mixture of the ore with charcoal is exposed to heat on the hearth of a reverberatory furnace fired with coal. °' * In the second, the tin ore is fused in a blast furnace, called a blowin^-house sunnlied with wood charcoal This method is practised in onl/a few works, in order to obtSI very pure quality of tin, called grain tin in England and etain en'/armS?n France a metal required for certain arts, as dyeing. Sec, This method is applied merely to stream In the smelting-hmses, where the tin is worked in reverberatories, two kinds of furna ces are employed ; the reduction and the refining furnaces. Figs. 1469, 1470, represent the furnaces for smelting tin at St. Austle, in Cornwall; the former being a longitudinal section! the latter a ground plan, a, is the fire- door, through which pitcoal is laid upon the grate 6; c, is the fire-bridge; er. — Now begins the second part of the process. Into the tin-bath, billets of green wood are plunged, by aid of the gibbet above described. The dis engagement of gas from the green wood produces a constant ebullition in the tin : bringing up to its surface a species of froth, and causing the impurest and densest parts to fall to the bottom. That froth, composed almost wholly of the oxydes of tin and foreign metals, is successively skimmed oft', and thrown back into the furnace. When it is judged that the tin has boiled long enough, the green wood is lifted out, and the bath is allowed to settle. It separates into diflerent zones, the upper being the purest ; those of the middle are charged with a little of the foreign metals ; and the lower are much contaminated with them. When the tin begins to cool, and when a more complete separation of its diflerent qualities cannot be looked for, it is lifted out in ladles, and poured into cast-iron moulds. It is obvious, that the order in which the suc- cessive blocks are obtained, is that of their purity ; those formed from the bottom of the basin being usually so impure, that they must be subjected anew to the refining process, as if they had been directly smelted from the ore. The refining operation lakes 5 or 6 hours ; namely, an hour to fill the basin, three hours to boil the tin with the green wood, and from one to two hours for the subsidence. Sometimes a simpler operation, called tossing^ is substituted for the above artificial ebullition. To eflect it, a workman lifts some tin in a ladle, and lets it fall back into the boiler, from a considerable height, so as to agitate the whole mass. He continues this manipulation for a certain time ; after which, he skims with care the surface of the bath. The tin is afterwards poured into moulds, unless it be still impure. In this case, the separation of the metals is completed by keeping the tin in a fused state in the boiler for a certain period, without agitation ; whereby the upper portion of the bath (at least one halO is pure enough for the market. The moulds into which the tin blocks are cast, are usually made of granite. Their capacity is such, that each block shall weigh a little more than three hundred weights. This metal is called block tin. The law requires them to be stamped or coined by public officers, before being exposed to sale. . The purest block tin is called refined tin. The treatment just detailed gives rise to two stanniferous residuums, which have te be smelted again. These are — 1. The scoriae b and c, which contain some granulated particles of tin. 2. The dross found on the bottom of the reverberatory furnace, after re-melting the tin to refine it. The scoriae c, are smelted without any preparation ; but those marked b, are stamped in the mill, and washed, to concentrate the tin grains ; and from this rich mixture, called frillion, smelted by itself, a tin is procured of very inferior quality. This may be readily imagined, since the metal which forms these granulations is what, being less fusible than the pure tin, solidified quickly, and could not flow off into the metallic bath. Whenever all the tin blocks have thoroughly undergone the process of liquation, the fire is increased, to melt the less fusible residuary alloy of tin with iron and some other metals, and this is run out into a small basin, totally distinct from the refining basin. After this alloy has reposed for some time, the upper portion is lifted out into block moulds, as impure tin, which needs to be refined anew. On the bottom and sides of the basin there is deposited a white, brittle alloy, with a crysUUine fracture, which contains so great a proportion of foreign metals, that no use can be made of it. About three au^ a half tons of coal are consumed in producing 2 of tin. Smelting of tin by the blast /umace.— This mode of reduction employs only wood 857 charcoal, and its object is to obtain tin of the maximum purity to which it can be broueh by man ufacturmg processes. The better ores of the stream-works, and the finer tin sands, are selected for this operation. The washings being always well performed, the oxyde Slinl^ilf .^fi>F/ k""™ ^^""'y arsenical or sulphurous impurity, and is associated with no- thing but a little hematite. It is therefore never calcined. The smelting is effected without addition; only, in a few cases, some of the reeiduary matters of a former operation are added to the ore. About a ton and six tenths of wood charcoal are burned for one ton of fine smelted tin. The only rule is, to keep the furnace always full of charcoal and ore. The revived tin is received immediately in the first basin ; then run off into the second, where it is allowed to settle for some time The scoriae that run off into the first basin, are removed as soon as they fix. These «5coriiB are divided m to two classes; namely, such as still retain tin oxyde, and sucll as hold none oi the metal m that state, but only in granulations. The metallic bath is divided by repose, into horizontal zones, of different degrees of purity ; the more compound and denser matters falling naturally to the bottom of the basin. The tin which forms the su perior zones, being judged to be pure enough, is transvased by ladles into the refining basin, previously heated, and under which, if it is of cast-iron, a moderate fire is applied 1 he tin near the bottom of the receiving basin is always laded out apart, to be aeaiiJ smelted ; sometimes, indeed, when the furnace is turning out very impure tin none of it is transvased into the second basin ; but the whole is cast into moulds, to be again treated m the blast furnace. In general they receive no other preparation, but the green wood ebullition, before passing into the market. Sometimes, however, the block of metal is j eated till it be- comes brittle when it is lifted to a considerable height, and let fall, by which it is broken to pieces, and presents an agglomeration of elongated grains or tears: whence it is called gram tin. On making a comparative estimate of the expense by the blowing-hcuse process, and by the reverberatory furnace, it has been found that the former yields about 66 per cent of tm, m smelting the stream or alluvial ore, whose absolute contents are from 76 to 78 parts of metal in llie hundred. One ton of tin consumes a ton and six tenths of wood charcoal, and suflers a loss of 15 per cent. In working with the reverberatory furnace It IS calculated that ore whose mean contents by an exact analysis are 70 per cent., yields 65 per cent, on the great scale. The average value of tin ore, as sold to the smelir, is 60 pounds sterling per ton ; but it fluctuates, of course, with the market prices. In 1 824, the ore of inferior quahty cost 30/., while the purest sold for 60/. One ton of tin, ob- tained from the reverberatory furnace, cost— 1 J tons of ore, worth ---.-. £J5 q q If tons of coals, at 10s. per ton - - . . 17 6 Wages of labor, interest on capital, &,c. - - - 3 78 17 6 On comparing these results with the former, we perceive that in a blowing-house the loss of tm IS 15 per cent.; whereas it is only 5 in the reverberatory furnace The ex- pense m fuel IS likewise much less relatively in the latter process; for only'lf tons of coals are consumed for one ton of tin ; while a ton and six tenths of wood charcoal are burned to obtain the same quantity of tin in the blowing-house; and it is admitted that one ton of wood charcoal is equivalent to two tons of coal, in calorific effect. Hence everv thing conspires to turn the balance in favor of the reverberatory plan. The operation is also, m this way, much simpler, and may be carried on by itself. The scoria, besides, from the reverberatory hearth, contain less tin than those derived from the same or« Ueated with charcoal by the blast, as is done at Altenberg. It must be remembered, how- ever, that the gram tm procured by the charcoal process is reckoned to be finer, and fetches a higher price ; a superiority partly due to the purity of the ore reduced and partly to the purity of the fuel. ' ^^ To test the quality of tin, dissolve a certain weight of it with heat in muriatic acid : Should It contain arsenic, brown-black flocks will be separated during the solution, and arseniureted hydrogen gas will be disengaged, which, on being burned at a jet, will fwlthlfl "'"^V?f^^^ film of metallic arsenic upon a white saucer held a little way above the flame. Other metals present m the tin are to be sought for, by treating thj above solution with nit"P/cid of spec. grav. M6, first in the cold, and it last with heat and a small excess of acid. When the action is over, the supernatant liquid is to be de- canted off the peroxydized tin, which is to be washed with very dilute nitric acid, and both Uquors are to be evaporated to dissipate the acid excess. If, on the addition of water to the concentrated liquor, a white powder falls, it is a proof that the tin contains bismuth; if on adding sulphate of ammonia, a white precipitate appears, the tin con- lams lead j water of ammonia added to supersaturation, will occasion reddish-brown :| 858 TIN. TIN. A. flocks, if iron is present; and on evaporating the anpernatant liquid to dryness, the copper will be obtained. 'Ae uses of tin are very numerous. Combined with copper, in diflferent proportions, it forms bronze, and a series of other useful alloys ; for an account of which see Odppeb. With iron, it forms tin-plate ; with lead, it constitutes pewter, and solder of various kinds (see Lead). Tin-foil coated with quicksilver makes the reflecting surface of glass mirrors. (See Glass.) Nitrate of tin att'ords the basis of the scarlet dye on wool, and of many bright colors to the calico-printer and the cotton-dyer. (See Scarlet and Tin Mordants.) A compound of tin with gold gives the fine crimson and purple colors to stained glass and artificial gems. See Purple of Cassius. Enamel is made by fusing oxide of tin with the materials of flint glass. This oxide is also an ingredient in the white a«d yellow glazes of potters-ware. The Exhibition contained a series of specimens, illustrative of an improved process for dressing ores of tin containing wolfram (the tungstate of iron and manganese, in- vented by Mr. R. Oxland, of Plymouth, for the separation of the wolfram from the ores of the Drake Walls tin mine, on the Cornish side c the river Tamar. This process is now in regular operation at the mine. In consequence of the specific gravity of wolf- ram, which is from 7100 to 7-600, being greater than that of the black tin of the mines or the pure native oxide of tin, which is only from 6'3 to 7*0, it has been found impos- sible to separate the wolfram from the tin oxide by the usual mechanical process of washing in a stream of water. This led to the necessity of adopting the patent chemi- cal process explained, with the description of the series of specimens. No. 1, "Tin witts:" the ore obtained from the stamp-floors, where, subsequentiy to its having been crushed or stamped down to a suitable size, it has been washed in a stream of water, in order to separate the earthy particles with which it was associated. The clean " witts" contain the native oxide of tin ; black tin or resin tin, and wolfram with iron and arsenical pyrites, generally containing some copper. In the course of washing, the " witts" are sorted into different parcels, according to the size of the particles, and are known as jigged, marked A; flucan, B; smalls, or "8male8,"C: slime, D ; roughs or rows, R The " witts" are calcined in a reverberatory furnace, usually constructed of fire-bricks throughout The calcination is continued until all the sulphur and arsenic is evolved. The residue of No. 2 contains black tin or native tin oxide, peroxide of iron, wolfram, some sulphate of copper, and a small quantity of earthy matter. By a series of wash- ing operations on the burning house floors, the peroxide of iron, sulphate of copper, and earthy matters, are removed, and the product obtained is No. 3, which consists of oxide of tin, with most of the wolfram. The process is in the next place employed for the removal of the wolfram. Its proportion having been ascertained by analysis, a quantity of sulphate of soda or salt cake is mixed with the ore, suflBcient to supply a slight excess equivalent of soda for the quantity of tungstic acid present ; but with the sulphate of soda must be mixed suflBcient coal dust or charcoal to afford carbon or car- buretted hydrogen, for the decomposition of the sulphuric acid and the conversion of sulphate of soda into sulphide of sodium. The mixture is exposed to heat on the bed of the furnace described below ; a smoky or reducing flame is at first employed, but after the whole of the chaise has been at a red heat for some time an oxidating flame is necessary to complete the operation. Thus the sulphate of soda is first converted into sulphide of sodium, then the tungstic acid of the wolfram combines with the soda, producing tungstite of soda, setting the sulphur free as sulphurous acid, and leaving the iron in the condition of a light, finely divided peroxide. The product No. 4 is drawn from the furnace into the wrinkle or chamber beneath, and is thence removed whilst still hot into tanks containing water, which quickly di»« solves the tungstate of soda. The solution is run off into receivers, and the residue is removed to the burning house floors, where by a series of washings the peroxide is re- moved, and the native oxides of tin obtained pure and ready for the smelting house as seen in No. 5 : an ore which had fetched only 42^. per ton has by this operation been BO much improved in quality as to obtain 56/. per ton. The tungstate of soda. No. 6, is obtained in the crystalline form by the evaporation to the crystallizing point of the solution in which it was separated from the tin. It is proposed to be used as a substitute for stannite of soda, a mordant for dyeing purposea Tungstic acid, No. 7, may be employed for the same purpose or for the manu- facture of tungstate of the tungstous oxide with soda, a compound much resembling gold. The tungstate of lead. No. 8, and tungstate of lime. No. 9, are good white pigments (manufactured from the tungstate of soda), from which was also obtained the metallic tungsten. No. 10, and sulphuret of tungsten, No. 11. The former is for use in the manufacture of metallic alloys; the latter has been proposed as a substitute for black 859 lead. The fiimace is composed in the usual manner, excepting that a cast-iron bed has been emp oyed to prevent the loss that would arise from the reaction of the silica of the bricks the soda and the tin oxide on each other. The fire after passing over the bed IS made to circulate beneatii it before passing away to the chimney. .liiSflt «r^^^'"!u'°^ ^*'''^'' ^^ *^^' ""^"^ ^^« ^'"o^^ «"«'ng from Uie furnace is Sf T ^^J^^^^^^th noxious vapors, containing besides other poisonous matters a large ?vT^ L tfl "^1^^ l^^'"'P*' ^^^^ ^^*° "^^^^ *« «^^«t« this nuisance; and the system adopted by the exhibitor has been found to be very successful tinn JliT • ^. building in solid masonry, about 80 feet in height, is divided by a parti- tion wall into two chambers, having a tall chimney or towSr adjoining, which com- municates with one of the chambers at the bottom. The smoke froS The varTo^ furnaces, 8 in number and about 100 yards distance from the condenser, is cafried by separate flues into a large chamber; from thence by a large flue it ekters the first chamber of the condenser at the very bottom, and is forced upward in a zigzag coui^ towards the top, passing four times through a shower of water, constantly percolating IZr \ £ff W- '•^!t™ V<^ the summit of the tower. The smoke is again compeUed to hlter a fifth time through a cube of coke some two feet square, tiirough wkich a stream gLTng of woo'd ^"^°^"^^^' «°^ ^^'^^ '' «°"fi°^^ to iS proper liSte by a verticS The smoke having reached the top is now opposite the passage into the second or vacuum chamber This is termed the exhaustiJJg chambe?, anf is abou^VfTby 7 feet mside, and 30 or more feet in height On its summit is fixed a large reservoir ^ttnf^ ^" ample stream of water, always maintaining a depth of 6 to 10 inches. Ihe bottom of this tank is of iron having several openings or slots, 12 in number and about an inch in width, and extending across the whole area of the reservorcommu- mcating directly with the chamber beneath. On this iron plate workra hyXX side-plate with openings corresponding in one position with those in the reservoir. This plate receives a horizontal reciprocating motion from a water wheel or other powS driven by means of a connecting rod and crank. power. In the middle of every stroke the openings in the plate correspond with those in the bottom ot the reservoir, and a powerful body of water falls as a shower bath the whole length of the vacuum chamber, and in doing so sweeps the entire inside area ca^yW Se furnareZ ^ " "' "'''"^'' "''''' ^'^^ ^"^^^"^^^ ^^ '^' y^V-^^^^^^l^l The atmospheric pressure of course acts in alternate strokes, as a blast at the furnace rHon^" T^ '^?'-' * ^''"^^' sufficiently strong to force the impure vapors through the var ous channels in connection wi^th the water, the wet coke, and exhausting chamber until It passes purified and inert, into the atmosphere. ^ ' n«S! w ^'' «at»rated witii particles of lead, Ac, held in mechanical solution, finally ScrcVa^g^^/tta^'" ^^ ^"^^^^"^ '^'^^^''^ ^- ^^^ P-P-' -^ there depo^U iS « Jtl^T^^I *^^i^'^ arrangement are most apparent and beneficial to the surroundincr neighborhood. Formerly the noxious fumes passing from the shaf^ of th?^,^o.i poisoned the neighborhood ; the heather wasVirnt^p vegeLttn desLoved a^^^^^ animal could graze, or bird feed near the spot Now the heftherX seen in^fuixfr^f nn^ halrb'er^rrcIpS^i/ ofEngland appear to been verv erudp nn/l fy,oi-». t«..*„ii • i ^^^ modes of working must have ^ Till a comparatively recent date, tin was the only metal which was souSt for • ar,^ !^ r.°J.llT n' rn' r' abandoned when the miner' cime to t^e ">eIlo^^^^^^ thai ^sti^aSvl l«r* "^.rPP?- . The greatest quantity of tin has been prol^ced by streaming (as washing the debris in the valleys is termed) ; and this variety callSl "stream tin," produces the highest price in the market ^' The conditions under which these deposites occur are curious and instructiye. At the 860 TIN. TIN. 861 IHPf nff tei Carnon Tin Stream Works, near of Falmouth, the rotnded pebbles of tin are found at a depth of about 60 feet from the surface, beneath the bottom of an estuary, where trees are discovered in their place of growth, together with human skulls, and the remains of deer, amidst the vegetable accumulation which immediately covers the stanniferous bed& According to Mr. Kenwood's measurement, the section presents first about 50 feet of schlieh and gravel; then a bed of 18 inches m thickness of wood, leaves, nuts, &c., restmg on the tin ground, composed of the debris of quartz, slate, and granite, and the tin ore. At the Pentuan Works, near St Austell, similar deposits, occur, proving a material alteration in the level, during the period expended m the formation of this deposit Tin is also worked out of the lode in many parts, the ore occurring both in the slate and granite formations. The modes of •' dressing the tin ore, jpreparing it for the smelter, and the process of smelting, were illustrated in the Ex- hibition. There has been a remarkable uniformity in the quantity of tin produced in Cornwall, during a long period, as will be seen from the following table : — Yean. Tons. Prices per cwt & s. 1750 1,600 1760 1,800 1770 2,000 1780 1,800 S 1790 2,000 8 15 1800 1,500 5 1810 1,400 7 1820 1,700 8 6 1830 8,500 8 1840 6,000 8 15 The produce of this metal within the last few years has been as follows :— Years. Tons. 1844 7,507 1845 7,739 1846 8,945 1847 10,072 1848 10,176 1849 10,719 Since 1838 the quantity cannot be accurately ascertained, the trade in tin being in the hands of a few, and the purchase of ore being usually made by private contract— See Metallic Statistics. Tin coating of iron and zinc, by Mr, Morries Sterling's patent process. Th% first improvement in coating metals or alloys of metals with other metals or their alloys^ relates to coating iron with tin or its alloys after the- iron has been coated with zinc. For this purpose the sheet, plate, or other form of iron, previously coated with zdnc^ either by dipping or by depositing from solutions of zinc, is taken, and after cleaning the surface by washing in acid or otherwise, so as to remove any oxide or foreign mat- ter which would interfere with the perfect and equal adhesion of the more fusible metal or alloy with which it is to be coated, it is dipped into melted tin, or an^ suita- ble alloy thereof in perfectly fluid state, the surface of which is covered with any suitable material such as fatty or oily matters, or the chloride of tin, so as to keep the surface of the metal from oxidation ; and such dipping is to be conducted in a like manner to the process of making tin plate or of coating iron with zinc. When a fine surface is required, the plates or sheets of iron coated with zinc may be passed between polished rolls (as already described) before and after, or either before or after they are coated with tin or other alloy thereof. It is preferred in all cases to use for the coat- ing pure tin of the description known as grain tin. Another part of the invention consists in covering either (wholly or in part) zinc and its alloys with tin, and such of its alloys as are sufficiently fusible. To effect this, the following is the process adopted :— A sheet or plate of zinc (by preference such as has been previously rolled, both on account of its ductility and smoothness) is taken, and after cleaning ita surface by hydrochloric or other acid, or otherwise, it is dried, and then dipped or passed in any convenient manner through the melted tin, or fusible alloy of tin. It is found desirable to heat the zinc, as nearly as may be, to the temper- ature of the melted metal, previous to dipping it, and to conduct the dipping, or passing through, as rapidly as is consistent with thorough coating of the zinc, to prevent as much as possible the zinc becoming alloyed with the tin. It is recommended also that the tin or alloy of tin should not be heated to a higher temperature than is necessary for its proper fluidity. The metal thus coated, if in the form of sheet, plate, or cake, can then be rolled down to the required thickness; and should the coating of tin or alloy be found insufficient or imperfect, the dipping is to be repeated as above described, and the rolling also if desired, either for smoothing the surface or further reducing the thickness. Another part of the invention consists in coating lead or its alloys with tin or alloys thereof. The process is to be conducted as before described for the coating of zinc, and the surface of lead is to be perfectly clean. The lead may, like the zinc, be dipped more than once, either before or after being reduced in thickness by rolling. The hydraulic press may be advantageously employed in the process of coating lead or its alloys with tm or its alloys; and this process is already practised and well understood, as applied to the coating of lead pipe with tin; it is only necessary to remark that a die or orifice must be used of such length and width as will allow an ingot cake or sheet to be formed. On both sides of this cake or sheet, melted tin is to be poured into a suitable receptacle, as is well understood in the making of pipe ; but where only one side or portion of the cake, ingot, or sheets is to be tinned, a partition or division should be placed to confine the melted tin, so that it shall only be applied to that portion of the lead which is re- quired to be tinned. Where a smooth surface is required, the cake or other form of lead 18 to be passed, while in a heated state, through a collar of suitable hard and smooth material, such as hardened steel or iron, kept as cool as may be. Where a strong coating of tin is required, the lead so coated is to be passed through melted tin. Such coated lead, or its alloys, may be reduced by rolling; and where the lead so coated 18 to be reduced to extreme thickness, the further coating is advantageously given after the coated metal has been reduced to some extent by rolling. Any number of addi- tional coatings may, in a similar manner, be given, according to the purpose for which the coated lead is required. In coating lead or its alloys with tin, it is recommended wk 1 PTO^f ^ ^^«^® a surface of lead is to be avoided, pure tin should be used. When lead is alloyed with antimony, zinc, tin, or any other metal, to render the lead more hard than lead m its ordinary state, the tin coating may also be somewhat hard- ened by alloying with zinc or other suitable hardening metal. Lead and its alloys may also be coated with tin or its alloys of greater fusibility than the metal to be coated as follows :— The cake, or other form to be coated, is to be placed as soon after casting as mav be in an iron, gun metal or other suitable mould, or if thia can not be conveniently done, the surfaces are to be cleansed and prepared, for the reception of the coating metal, either by previously tinning the surface, or by applying other suiteble material to facilitate the union, as heretofore practised. At one end of the mould 18 to be attached chambers, of more than sufficient capacity to contain the quantity of metal to be used for coating, which may with advantage form an integral part of the mould, or such chamber may surround the mould, and by one or more sluices or valves in such chamber or chambers, the melted metal is to be allowed to run on to the surface of the metal to be coated, when the metal is to be coated on one side only. When It IS mtended to coat the metal on both sides, the vertical position will be found convement^ and the coating metal is to be formed into a chamber or chambers attached to the mouldy and to be introduced into the lower part of the mould by opening a sluice or valv^ sufficient space being left on each side of the cake or other form to alfow of the coating being of the required thickness ; the sluice or valve should be of nearly the width fLl"?. tbe cake or other form, and the melted metal should be aUowed to flow into toe bottom of the mould (Mr. Stirling here observes, that he is aware that lead has S!!f if T""^^ ^A'i?*^'^'^'^^ ^''^ ^7 P^"^^"g ^i'l "P«° ^^^ lead, and also by pressure, and toat he does not therefore claim the coating of lead by such means). The surface of the plate or cake ought to be smooth and true, and the mould, if horizontal, to be perfocUy 80^ and If upright, quite perpendicular, so as to insure in either case an equal footing. The surface of the lead should also be clean, and it wiU be found advantageous to rai^ Its temperature to a pomt somewhat approaching the melting point of tin?r of the alloy employed for coating, as by this means the union of the two metals is facilitated. It ik recommended also that a somewhat larger quantity of the tin or alloy than is necessary for the coating of the lead or other metal, or alloy, should be emploved, and that when the requisite thickness of coating has been given, the flow of Uie coating metal be stopped, •8 by this means the impurities on the surface of the tin wiU be prevented passing 862 TIN-PLATE. il m%\ K tiirongh the opening on to the surface of the cate: the chamber or chambers should be kept at such temperature as to ensure the proper fluidity of the coating metal Zinc and its alloys may m like manner be coated with tin and its alloys, by employing a bke apparatus to that just described for coating lead and its alloys, knd it constitutJ a part of this invention thus to coat zinc. The coating of zinc with tin, however, is not claimed, that having been done by pouring on tin. Another part of the invention consists in coating zinc and its alloys with tin and its a oys by pressure. For this purpose Mr. Stirling takes a suitable piece of zinc or alloyed zmc (by preference previously rolled), and when it is desired to coat it on both sides with tin or alloyed tin, of sufficient dimensions to completely cover the zinc. He then subjects the metal so placed to pressure, to obtain perfect contact- and for this purpose when making shee^ he employs rolls, and rolls out the two metkls to the extent desired. The last part of the invention relates to the employment of zinc when welding to- gether plates or other forms of iron, which is principally applicable when piling Iron, Thm sheet zinc, placed between the layers, has been found to answer well; but the use of calamine, m the form of powder or paste, is preferred. In the latter case the paste may be formed with water, to which a small quantity of borax may be added • the paste can be then applied with a brush or otherwise, to the surface of the plates or other forms of iron. Additional stiffness and toughness are produced by this process. ^tatVi A?^^^ ^^^^V^ believed to be more particularly benefited thereby. 1 INC AL, crude borax. ^ TINCTORIAL MATTER. One of the most curious and valuable facts ascertained mpon this subject, is, that madder kept in casks, in a warm place, undergoes a species of lermenlation, which, by ripening, or rather deoxydizing the coloring-matter, increases its dyeing power by no less than from 20 to 50 per cent. See M. H. Schlumberger's memoir read to the Societe Indusinelle de Mulhausen, 24 November, 1837. riNCTURE is a title used by apothecaries to designate alcohol, in a somewhat substlnce*^ ' impregnated with the active principles of either vegetable or animal TIN-GLASS is a name of bismuth. TIN MORDANTS, for dyeing scarlet :— M(yrdant a, as commonly made by the dyers, is composed of 8 parts of aquafonis, Sncertair™"*''' ' '''" ammoniac, and 1 of granulated tin. This preparation it ver^ M^dant B.-Pour into a glass globe, with a long neck, 3 parts of pure nitric acid at Z.J ^ f ^ ""^ T"^^'"" ^""'^ ^^ ^'^° 5 shake the globe gently, avoiding the corro- sive vapors, and put a loose stopper in its mouth. Throw into this nitro-muriatic acid one eighth of its weight of pure tin, in small bits at a time. When the solution is com- plete and settled, decant it into bottles, and close them with ground stoppers. It should be diluted only when about to be used. .J!rfr^ ""'■ ^^ ?ambourney.-In two drachms Fr. (144 grs.) of pure muriatic acid,dis. solve 18 grains of Malacca tin. This is reckoned a good mordant for brightening or hxing the color of peachwood. ^ ^ ^J^<^dant^ by Hellot.— Take 8 ounces of nitric acid, diluted with as much water; disso ve m it half an ounce of sal ammoniac, and 2 drachms of nitre. In this acid solution mt:^::eZry>:i^^t' '" '' "^"""^"^ ^'"^"^"^ "°^ ^° ^^^ ^^ ^ ^^^^^ p^^- Mwdant e, by Scheffer.— Dissolve one part of tin in four of a nitro-muriatic acid, nre- sa/ammonia"c^'"''' ^""'^ ^^^""^^^ ^'^^^ '^^ °'^'' ^^'^^^ ""^ '^**"' ^^ """^ thirty-secondth of JfordantF by Poerner.--Mix one pound of nitric acid with one pound of water, and dissolve m it an ounce and a half of sal ammoniac. Stir it well, and add, by very slow degrees two ounces of tin turned into thin ribands upon the lathe. Mordant g, by Berthollet.-Dissolve in nitric acid of 30° B. one eighth of its weight tinnlT^''" r"' ^^uV^^ by degrees one eighth of its weight of tin, and dilute the soln- tion with one fourth of its weight of water. Mordant k, by Dambourney.— In one drachm (72 grs.) of muriatic acid at 17°, one of of fine^Malacca tin^ ^'^'"^ ""^ ^^^''''' dissolve, slowly and with some heat, 18 grains Mordant L is the birch bark prescribed by Dambourney.— This bark, dried and ground, iS said to be a very valuable substance for fixing the otherwise fugitive colors pfoduced by woods, roots, archil, &c. * wu^^ou TIN-PLATE. The only alloy of iron interesting to the arts is that with tin, in the formation of tin-plate or whtte-ir&n, ' The sheet iron intended for this manufacture is refined with charcoal instead of coke. subsequently roUed to various degrees of thinness, and cut into rectangles of different TIN-PLATE. 863 bo2s^/dT°or fo^Hm^1?^^^^ ^'^'l \ * water-^heel, which will turn out 100 ninff is to free thl mP in- ^^V'^'^^J'^^ <5°fc by hand labor. The first step toward tin- «r,fii • -fVi "^^^^^<^ surface from every particle of oxyde or impurity, for any sneh se^JitS^^^^^^^ *'Lr '""i ^"°^'^"5 -^^^ ^^^ ^-- TheTates are ne7t beS IhTflame mav nil ? T^**^^ *"* ^u'^'^P^' ^"'^ '^"^^^ ^^ « reverberatory oven, so that ninna!J^^ f ^^.^!t^ ^'^^^^ ^"°"^ ^^^°^» ^""^ ^^at them to redness. They are then plunged into a bath, composed of four pounds of muriatic acid diluted with three laUons to fl. ' ^-^ * ^r "''""*"'' '^^"" «"* ^"d '^^^i^ed «" the floor, and once more elpo^^ to Ignition m a furnace, whereby they are scaled, that is to say, cast IheTr Tcales '^ «t°ooth ''^ ""'" '"?'' ^'^. ^^"^^"^ ^^^^ P'^^^«- When takenl', they arTbeafL^el lid smooth on a cast-iron block, after which they appear mottled blue and whie if the Lon o?1 If ^''" i^°T^^^^ ?""!• ^^'^ «^^ next passed through chmed Tolls or ciS^ Xtilid hvT^'S'tl r^^"^.^y ^"^"^ '^'' ^" '^''^ i^«" °^«"Ws, as has been ^ pract sed by the Scotch founders in casting bushes for cart-wheels After Oii^nrripJ of co/d ro//mg, the plates are immersed, for ten or twelv" Tours in aif acSSoSs^ef Jjade by fermenting bran-water, taking care to set them separa"e^y on ^ge and to t„m them at least once, so that each may receive a due share of the oneraUon From th^ ley-steep they are transferred -into a leaden trough, divided by parUtioTandchar^Jd ^A diute sulphuric acid. Each compartment is called a hole by ^hrCkmen and is caTc? }SUr''T7.'^^°"' ^^^ plates, the number afterwards packerupTogether in TiS' f^m . rt ' u'^ ^'^ ^^'^^^ *^"' ^"^ ^^"'■^ *•» they becoL perfectly bright Lnd ^ from such black spots as might stain their surface at the time of unmSsion Thi, n^ rumsLcf '" ^'^^""'^ ^"' '■™'" ™^' f" "■"-y months, a ver?remriablec" are thence removed, with the Zherine '"ease int^ tt%i ,"^^7" i""- ^^I the superflu^metal^S -^ - -^ Z^^^^S^ ^^ ^^^^^ plie^ltr?tt^hU^°cieL^^^^^^^ tin the workman puts the above in it, for keeping the droTof tin ^h J r L • '"""^b ^r^'^ '' * longitudinal partiUon the ast dip is grven Inde^ the iL ' \l u^ ^'^^ "^"'"""^ '^'^ ^^^^^^ ^^^re 70 boxes, becomes so foul that th^wpiih/r ^^^T\^J^^' ^^^^"^ ^'''^ «« 6^ or into the lin-pot, No. 1, and rep aceS Tv f frplh^K f^^ ^"^'^^ V '' transferred lifted out of ihe wash-pot7w[th tont heVin the left h^l^n^T ''"* ^ ^^' ^^^''' ^'^^ on each side with a neculiar hVm«^„ T u V ,J • . "^ °^ ^^^ workman, are scrubbed moment in Ihriot tin aS forthwhhL "'^'i'"^'^ i" ^^- '^'^^'' *^^"^' ^^^^ ^^^PPed for a requires manual dexterity ;an5lhou^^^^^^^^^^ ^"^'T^^ ^rease.j^oU No" 3. This washing 225 plates, yet a good wSan cl^tT^^^^^ ^^Vl' ^'^'^''^ ^"^ ^^' hours, by putting 5625 pktes trro^TXis hand" Thl &• "^'^-''n"? ^'^ '^^^^« the marks of the brush and to Zlo tl r ^^^^..^^^l tm-dip is useful to remove temperature of the allow-^t Ind^Lf. • "'^^l' Tf"^}^ ^'''^^'' ^o regulate the great skill and circSnspLS on thrn«rf.^^^^ ^^^If ^'^ ^^" ^^ it, requires would be deprived, t^a^ certain exten? of 1 ^^^ ^°^^°^f "' ^^ kept in it too long, they Of tin would disfigure their surface V/^th- f''^^ ^"'''^.' ^'^^ '^ ^^ '^""''^ '^'^^^ lifted out of the washina pot Tream-rp^ « *^^*^^ P^^^^/^tains more heat after being has pins fixed within it! to keenX nl„^.P'''P°?^"^"^^°*'^^^ grease-pot. This p?t transferred five plates to i a W^iftsthlT.^'"''^^^ and whenever the workman has soon as the wofkmTntransfe^V sixth nl.?. T T '^' '"^^ ^^J^^*^^"' P^°' No. 4;^ The manufacture is compS by remo^^^^^^^ boy removes the second ; and so on. plates, in consequence of their veS Josh n„ Tth ""^ *'" r^' ""^ '^' "'^^"^ "^"^ «^ '^^ H c ui lucir venicai position m the preceding operations. This is the li 864 TIN-PLATE. TOBACCO. 86f litiiifi business of the list-hoy, who seizes the plates when they are cool enough to handle, and puts the lower edge of each, one by one, into the list-pot, No. 5, which contains a very little melted tin, not exceeding a quarter of an inch in depth. When he observes the wire-edge to be melted, he takes out the plate, and, striking it smartly with a thin stick, detaches the superfluous metal, which leaves merely a faint stripe where it lay. This mark may be perceived on every tin-plate in the market. The plates are finally prepared for packing up in their boxes, by being well cleansed from the tallow, by friction with bran. Mr. Thomas Morgan obtained a patent, in September, 1829, for clearing the sheet-iron plates with dilute sulphuric acid in a hole, instead of scaling them in the usual way, pre- vious to their being cold rolled, annealed, and tinned ; whereby, he says, a better article is produced at a cheaper rate. Crystallized tin-plate, see Moiree Metallique. It would seem that the acid merely lays bare the crystalline structure really present on every sheet, but masked by a film of redundant tin. Though this showy article has become of late years vulgarized by its dieapness, it is still interesting in the eyes of the practical chemist. The English tin- f^tes marked f answer well for producing the Moiree, by the following process. Place tke tin-plate, slightly heated, over a tub of water, and rub its surface with a sponge dipped in a liquor ccnnposed of four parts of aquafortis, and two of distilled water, holding one part of common salt or sal ammoniac in solution. Whenever the crystal- lint ipangles seem to be thoroughly brought out, the plate must be inunersed in water, washed either with a feather or a little cotton (taking care not to rub off" the film of tm Chat forms the feathering), forthwith dried with a low heat, and coated with a lacker varnish, otherwise it loses its lustre in the air. If the whole surface is not plunged at once in cold water, but if it be partially cooled by sprinkling water on it, the crystalli- zation will be finely variegated with large and small figures. Similar results will be obtained by blowing cold air through a pipe on the tinned surface, while it is just passing frcHu the fused to the solid state; or a variety of delineations may be traced, by playing over the surface of the plate with the pointed flame of a blowpipe. The following Table shows the several sizes of tin-plates, the marks by which they are distinguished, and their current wholesale prices in London : — Names. Sizes. No. in a box Weight of each box. Marks on the boxes. Prices per box, in 1 1823. 1838. Inches. cwt. qrs. lbs. a. 9. d. Common, No. 1 13| by 10 226 1 CI. 47 35 Ditto 2 - I3i-- 9i . 3 21 CII. 45 33 6 Ditto 3 121— 9i - 3 16 cm. 43 32 9 Cross, No. 1 131—10 . 1 1 XI. 53 40 2 Two crosses, 1 - . 1 1 21 XXI. 58 43 2 Three crosses, 1 . 1 2 14 XXX. I. 63 47 Four crosses, 1 . . 1 3 7 XXXX. I. Common doubles - 16J — 12| 100 3 21 CD. 64-61 .50 48 6 Cross doubles . . 1 14 X7^. 73-6 sheets 66 Two cross do. . . 1 1 7 XXD. 81 > m 60 6 Three cross do. . . 1 2 XXXD. sjuej each. 66 Four cross do. . . 1 2 21 XXXXD. Com. small doubles - 6—11 200 1 2 CSD. 69 51 6 Cross do. do. - . «• 1 2 21 XSD. 75 56 Two cross do. . . 1 3 14 XXSD. 80 59 6 Three do. do. . • 2 7 XXXSD. Four do. do. - _ _ 2 1 XXXX80. / Waster's com. No. 1 3f— 10 225 1 WCI. 44 32 9 Ditto cross, 1 ditto - 1 1 WXI. 50 47 3 These are the cash prices of one wholesale warehouse in Thames street ; an imme- diately adjoining warehouse charges fully Is. more upon the standard ci, and propor- tionally upon othera Tin plate working in the Exhibition. Jackson, W., Birmingham, manufacturer. Anvil for planishing tin plate. Hammers assorted for tin and copper work. Crease-iron or wireing stake for tin. General swage to hold diflferent tools, for beading tin. Bick- iron for tin plate, and side stake for tin or copper work. Bottom stake, for planishing copper. Pair of stock shears and hand shears for cutting tin,' copper, Ac Model of a raising machine for raising dish covers, \\ inch in scale. oi^Zt td tCh .r'' -^"'M P'^^' "^^^^^ ''' enumerated in the above colleetio. eL^n su^?8eded th! n/r'''"C ^J "'r'?' ^? "spinning" and stamping has Uy a great bSk ronTith th.tVi'' ""^^°^' f V""^ ^^'•^^"^' ^^« P^J'^»»«d «nvil stakes or y^ he dispentd Witt 7^^^^^^ plan.sh.ng-faced hammers of various forms, cannot Avoided Sni.minJ^n ! ^\^ n«w mode of production seam-soldering is entirely w^U. densen^erof ix^ M '^n^'"^' ^9^''^^^''^^' ^'^'^ «^ firmness and solid!^ I^-ticles to effecf fh'uW ^^^"^^^/"g 'V^*'^ necessary in the manufacture of certain TOBACCO. It IS said that the name tobacco was ^iven by the SnaniardsVo ihl l^l* because it was first observed by them at Tabasrn or T«KL-^i o ^P^P^*™^^*'*^ ^^^^^ «ml „„ ,,k return i„,o France,' ,o Catherine orMXisrtent'i "has b^en S plant was cultivated in Britain before the rear loTO • «nH ^^1 ^^^^^"^'"f }^ ^-^^el, this covered up, and left to swLt forTweek orT«4 aceord^ni" o Z"''' 'I"'"'*^ Z^''^ of the season; durins which time thev n,„ J k'« 1 •^j^'*'^''^ ''''''''>' '"^ 'he state ^"hrpro-^S t^^^-B Si \S "~- pSSelt.^ d^riro^rhLr^"''-"--^^^^^ kZ^I l"^^"' M "? V"P^'^' <"■ ""«" Without fermentation, is sent into the market ■ but q::^u\^:^x^ fft^^L^itTst^^r ""'"■' ='" '""•™''""' "-•> •"»- '«« thev nr!;?ifp'','°'ll'' '.''''■"=<=<'"'^'? "'e very careful to separate all the damaged leaves, before ^t^Z, wafer nt'LTch";:'"'™' "'■''" ."'^y <*» byspreading them in a heap upon'asto« l«vcracnt,\vaicung each layer in succession with a solution ofsea salt, of soec .rav I-im 1^„!. n .u . ' ' ^""f"!'"? to the temperature, and the nature of the tobacco It is hi^hw rttw': atrk'if af T'""'"? r?"" ""^"^ odors, anV^^p^^Mlyof'^l^ «mi.< m„r^l!. .. ,i ^'^^'' Si^een leaf of tobacco be crushed between the fin^ersTtt ^cutiarodorofnuH- itva„',l"!f "^"T •""*'"'" "'» ™'»«liately exhale thj .rSuc:rabuXnce%?amm^^^ "-^"^'^^^ principle, which by fermentai^n chiefly in mode 'tint the ?prml t .' ' ^^« 5>dorous principles. The salt water is useful factive srni^ Tus a', nft [ff ""'?^'°"' ^"f preventing it from passing into the putre- rtemne rheVeimenta iv^ n sometirnes added to saccharine worts in tropical countries, l^ns some Ll^P^^^^^^^^^^^^ . ?' ''V''^^' «^ concentrated sea water, which con! tTpure chlodSe of sod i^^^^^^^ '^ ^''^ the tobacco moist, and is therefore preferable salt LLf ^d L/rih. n^h ^V?.?"'PT^- ^'""^ tobacconists mix molasses with the salt sauce, and ascribe to this addition the violet color of the macouba snuff of Mar! 866 TOBACCO. tiniqiie ; and others add a solution of extract of liquorice. Tlie following prescription » that used by a skilful niaiiufacturei:--In a solution of the liquorice juice a few figs are to be boiled for a couple of hours ; lo the decoction, while hot, a few bruised anise-seeds mre to be added, and when cold, common salt to saturation. A little silent spirit of wine being poured m, the mixture is lo be equably, but sparingly, sprinkled with the rose of a watering-pot, over the leaves of the tobacco, as they are successively stratified upon the preparation floor. * The fermented leaves, bein? next stripped of their middle ribs bv the hands of chil- dren, are sorted anew, and the larjje ones are set apart for making cisars. Mo^t of the tobaccos on sale in our shops are mixtures of different growths: one kind of smokin«' tobacco, for example, consists of 70 parts of Maryland, and 30 of meager Virginia ; and one kind of snufl consists of 80 parts of Virginia, and 30 parts of either Humesfort or Warwick. The Maryland is a very light tobacco, in thin yellow leaves; that of Vir- ginia IS m large brown leaves, unctuous or somewhat gluey on the surface, having a smell somewhat like the figs of Malaga ; thai of Havana is in brownish, light leaves, of an agreeable and rather spicy smell ; it forms the best cigars. The Carolina tobacco IS less unctuous than the Virginian ; but in the United States it ranks next to the Maryland. The shag tobacco is dried to the proper point upon sheets of copper. Tobacco is cut into what is called sha? tobacco by knife-edged chopping stamps, a ma- chine somewhat similar to that represented under METALLURGY,y^g. 670.^ For grinding the tobacco leaves into snuff, conical mortars are employed, somewhat like that used by the Hindoos for grinding sugar-canes, fig. 1080; but the sides of the snuff-mill have sharp ndifes from the top to near the bottom. J^u 1^' ^* ^"^^^ obtained a patent in August, 1827, for a tobacco-cutting machine, which bears a close resemblance to the well-known machines with revolving knives, for cutting straw into chaff. The tobacco, after being squeezed into cakes, is placed upon a smooth bed within a horizontal trough, and pressed by a follower and screws to keep it compact. These cakes are progressively advanced upon the bed, or fed in, to meet the revolving blades. The speed of the feeding-screw determines the degree of fineness of the sections or particles into which the tobacco is cut. I was employed some years ago by the Excise lo analyze a quantity of snuff seized on suspicion of having been adulterated by the manufacturer. I found it to be largely drugged witli pearl ashes, and lo be thereby rendered very punsent, and absorbent of moisture ; an economical method of rendering an effete article at the same time active aad aqueous. According to the recent analysis of Possett and Reimann, 10,000 parts of tobacco. leaves contain — 6 of the peculiar chemical principle nicotine ; 1. of nicotianine ; 287 of llightly bitter extractive; 174 of gum, mixed with a little malic acid; 26-7 of a green resin ; 26 of vegetable albumen ; 104-8 of a substance analogous to gluten ; 51 of malic acid; 12 of malate of ammonia; 4*8 of sulphate of potassa; 6*8 of chloride of potassium; 95 of potassa, which had been combined with malic and nitric acids* 16-6 of phosphate of lime; 24-2 of lime, which had been combined with malic acid; 8-8 of sihca; 496.9 of fibrous or ligneous matter; traces of starch; and 8828 of water' Nicotine is a transparent colorless liquid, of an alkaline nature. It may be dis- tilled ma retort plunged into a bath heated to 290° Fahr. It has a pricking, burninff taste, which is very durable ; and a pungent disagreeable smell. It burns by means of a wiek, with the diffusion of a vivid light, and much smoke. It may be mixed with water in all proportions. It is soluble also in acetic acid, oil of almonds, alcohol and etfier, but not in oil of turpentine. It acts upon the animal economy with extreme violence; and in the dose of one drop it kills a dog. It forms salts with the acids. About one part of it may be obtained by very skilful treatment from one thousand of good tobacco. Virginia leaf costs in bond ^d. per lb., the duty is 1,100 per cent Ditlo strips " 5\d. " 700 " Ditto strips Kentucky leaf Ditto strips Havanna cigars Manilla cheroots East India cheroots 5; sU 8*. G«. If. Negrohead and Cavendish 6d. Bates of duty on tobacco in foreign countries:— 700 1,200 800 112 150 900 1,800 <« M « Austria— leaf tobacco Belgium ditto ... Bremen ditto, ^ per cent, ad valorem Denmark leaves and stems Prussia Saxuny Bavaria j Zoll-Verein) Brunswick ) States. ) Wirtemberg Frankfort on the Maine Per EiiKliab Pound. • 3d. - id. 2d Tn Englisk Pound. Other German States Hamburgh § per cent, ad valorem. Holland 2 per cent, ad valorem. Ditto, cigars .... Ionian islands, leaf stems Ditto manufactured Rassia 30 per cent, ad valorem on foreign. Sweden imd Norway - about IdL 2dL Sd TOBACCO-PIPES. 867 A f^tnet royal monoply {r^gie) exists in Austria Proper, France, Sardinia, the Duchies of 1 at-ma and Lucca, and the Grand Duchy of Tuscany ; and in Portugal, Spain, Naples, and the States of the Church, the license to manufacture is periodically sold to com- panies, which regulate the price of tobacco as they please. It will be found that the situation of all these countries where the monopolies and high prices are kept up, is neariy the same, as to illicit trade in tobacco, as in England. No measure short of a reduction of the duty to U. per lb. can put a stop to it The following analysis of 10,000 parts of fresh tobacco, by Posselt and Reimann. will show the exceeding complexity of this substance : — Nicotine . . . . Nicotianine - . . . Extractive matter, slightly bitter Oum with a little malate of lime Oreen resin ... Vegetable albumen Substances analogous to gluten - Malic acid .... Malate of ammonia Sulphate of potash 6 1 287 174 26-7 260 104-8 510 120 4-8 Chloride of potassium - - . Potash combined with melic and nitric acids Phosphate of lime - •• . Lime in union with malic acid Silica ..... Woody fibre Water (traces of starch) 6-3 95 16C 24-2 88 496-9 - 8,828-0 10,000-0 In Silliman's Journal, vol. vii. p. 2, a chemicnl examination of tobacco is given by Dr Covell, which shows its components to have been but imperfectly represented in the above Gerinan analysis. He found, 1, gum ; 2, a viscid slime, equally soluble in water and alcohol, and perceptible from both by subacctate of lead ; 3, tannin- 4 gallic acid- 5, chlorophyle (leaf-green); 6, a green pulverulent matter, which dissolves in boiling water, but falls down again when the water cools; 7, a yellow oil, possessing the smell taste, and poisonous qualities of tobacco; 8, a large quantitv of a pale yellow resin- 9, nicotine; 10, a white substance, analogous to morphia, soluble in hot, but hardly m cold, alcohol ; 11, a beautiful orange-red dye stuff, soluble only in acids: it defla- CTates in the fire, and seems to possess neutral properties; 12, nicotianine. In the infusion and decoction of the leaves of tobacco, little of this substance is found - but after they are exhausted with ether, alcohol, and water, if they be treated with sul- phuric acid, and evaporated near to dryness, crystals of sulphate of nicotianine are ob- tamed. Ammonia precipitates the nicotianine from the solution in the state of a yel- lowish white, mit powdering r«atter, which may be kneaded into a lump, and is void Of taste and smell, as all its neutral saline combinations also are: its most characteristic fd/a^ ^* forming soluble and uncrystallisable compounds with vegeUble According to Buchner, the seeds of tobacco yield a pale yellow extract to alcohol which contains a compound of nicotine and sugar. Kepertorium fur die Pharmacil MM. Henry and Boutron Charlard found in 1000 parts of Cuba tobacco Maryland - Virginia He et Vilaine Lot et Garonne more than were obtained by Posselt and Reimann. 1 *,*l^J'^*""^'^® of tobacco retained for home consumption in 1842, amounted to nearly 17,000,000 pounds. Professor Schleiden gives a sfngular illustratTon of the iroclS^OOOntr^r^^ri!^- North America alone produces annually upwards of 200,000,000 of pounds of tobacco. The combustion of this mass of vegeteble material would yield about 840,000,000 pounds of carbonic acid gas, so that thf yearly produce foSSoooooo';:^,^'.''^'T ^b««««T"^^"S alone, canlot be estimat^ atiL than ino^fb. '«f P I "^'i \l"^^^ contribution to the annual demand for this gas made upon the atmosphere by the vegetation of the worid. ^ SfiTfifi^'S 'ihf^'^-^ il^?/^o^, .^?^^"^ Kingdom, viz.: -unmanufactured, in 1850. ffiJ?M«lJ •' ,'?«i^o\\,^^'^^ '^^^ lbs.; -manufactured, and snu^ in 1850 tSYn 18.o' 9? ?«\'n!'^K^'^'' ^^'- ^^'^'"^^ f^^ ^^"'^ consumption, unmanufael S'i?A A«i 'iK '^^^'loti^ol'" ^^?^' 27,863.390 lbs. ;-manufactured, and snuff, in in 1 85^ 4 33J 2.8/' '"in 1 «^.'iT^/A\'^n^ ^"'^ receiTed,-on unmanufactured tobacco! 92,8?3?;;1'nT851 '9^.858^'^' '''''''''' ' ^° "«-^««tured (.bacco. and snuff, in 1850.' nia^^ntt^nn^;ri^^- 7»^^J>^««tice of smoking tobacco has become so general in Strv Snr?.^ T^V^. the manufacture of tobacco-pipes a considerable branch of WJnTW f. K K « "• ^w ^"f^^on of tobacco-smoke a p'leasurable narcotism ; others ^ZrZ inW '""'^''^^ *^'t'''• ^'".^^^ ' ^""^ ^° general, smoking is merely a dreamy resource against ennui, which ere long becomes an indispen^ble stimulus. The 8*64 of nicotine; 6-28 10-00 11-20 8-20 ; quantities from 12 to 19 times Hi i I i 868 TOBACCO-PIPES. iiih!! filthiness of this habit, the offensive odor which persons under its influence emit from their mouths and clothes, the stupor it too often occasions, as well as the sallow complexion, black or carious teeth, and impaired digestion, all prove the great consumption of tobacco to be akin in evil influence upon mankind to the use of ardent spirits. Tobacco-pipes are made of a fine-grained plastic white clay, to which they have given the name. It is worked with water into a thin paste, which is allowed to settle in pits, or it may be passed through a sieve, to separate the silicious or other stony impurities ; the water is afterwards evaporated till the clay becomes of a doughy consistence, when it must be well kneaded to make it uniform. Pipe-clay is found chiefly in the isle of Purbeck and Dorsetshire. It is distinguished by its perfectly white color, and its great adhesion to the tongue after it is baked; owing to the large proportion of alumina which it contains. A child fashions a ball of clay from the heap, rolls it out into a slender cylinder upon a plank, with the palms of his hands, in order to form the stem of the pipe. He sticks a small lump to the end of the cylinder for forming the bowl ; which having done, he lays the pieces aside for a day or two, to get more consistence. In proportion as he makes these rough figures, he arranges them by dozens on a board, and hands them to the pipemaker. The pipe is finished by means of a folding brass or iron mould, channelled inside of the shape of the stem and the bowl, and capable of being opened at the two ends. It is formed of two pieces, each hollowed out like a half-pipe, cut as it were lengthwise ; and these two jaws, when brought together, constitute the exact space for making one pipe. There are small pins in one sidfi of the mould, corresponding to holes in the other, which serve as guides for applying the two together with precision. The workman takes a long iron wire, with its end oiled, and pushes it through the soft clay in the direction of the stem, to form the bore, and he directs the wire by feeling with his left hand the progress of its point. He lays the pipe in the groove of one of the jaws of the mould, with the wire sticking in it ; applies the other jaw, brings them smartly together, and unites them by a clamp or vice, which produces the external form. A lever is now brought down, which presses an oiled stopper into the bowl of the pipe, while it is in the mould, forcing it sufficiently down to form the cavity ; the wire being meanwhile thrust backwards and forwards so as to pierce the tube completely through. The wire must become visible at the bottom of the bowl, otherwise the pipe will be imperfect. The wire is now withdrawn, the jaws of the mould opened, the pipe taken out, and the redundant clay removed with a knife. After drying for a day or two, the pipes are scraped, polished with a piece of hard wood, and the stems being b-nt into the desired form, they are carried to the baking kiln, wnich is cfipaWe of firing f.fty gross in from 8 to 12 hours. A workman and a child can easily make five gross of pipes in a day. No tobacco-pipes are so highly prized as those made in Natolia, in Turkey, out of meerschaum, a somewhat plastic magnesian stone, of a soft greasy feel, which is formed into pipes after having been softened with water. It becomes white and hard in the kiln A tobacco-pipe kiln should diffuse an equal heat tc every part of its interior, while it excludes the smoke of the fire. The crucible, or large sagger, a, a, figs. 1473 and 1474, is a cylinder, covered in with a dome. It is placed over the fireplace b, and enclosed within a furnace of ordinary brickwork d, d, lined with fire-bricks e, e. Between this lining and the cylinder, a space of about 4 inches all round is left for the circulation of the flame. There are 12 supports or ribs between the cylinder and the furnace lining, which form so many flues, indicated by the dotted lines a*, in Jig. 1474 (the dotted circle representing the cylinder). These ribs are perforated with occasional apertures, as shown in Jig. 1473, for the purpose of connecting the adjoining flues ; but the main 1474 bearing of the hollow cylinder is given by five piers, 6, b, c, formed of bricks projecting over and beyond each other. One of these piers c, is placed at the back uf the fireplace, and the other four at the sides b, b. These project nearly into the centre, in order to support and strengthen the bottom ; while the flues pass up between them, unite at the top of the cylinder in the dome l, and dis- charge the smoke by the chimney n. The lining F, E, E, of the chimney is TOOTH FACTORY. •Den on one side to form the door, by which the cylinder is charged and discharged, ^h ZT^ « permanently closed as high as k, /g. 1473. by an iron plate plastered 3hltTpr^' ^^"^^ ^-^''" '^^^^ open, and shut merely with temporary brick-work tTrnll rh ''''*''^'' ^T^' y^^^"" ^^^^ i^ removed, the furnace can be filled or emptied whTa ?« I T"*"l' '^^ cyhndric crucible having a correspondent aperture in its side, wo kman fi?f '" ^^' ^?"°^^"p ^"^^'^'^"^ ^^^^ "^^^^ '^^ ^^^uace is in action. The ^em, nf w? '^''^- ' * ^^^^'f ""^^^ '*°"'*^ '^^ ^^?« °^ ^^^ opening, he then sticks the wffh Hw Iv M ^,T' across from one side to the other, and plasters up the interstices with clay, exactly like the lath-and-plaster work of a ceiling. The whole of the cylinder, indeed, is constructed in this manner, the bottom being composed of a great many w?rh"!ffM ^r^^ ''^™?' radiating to the centre; these are coated at the circumference 7hlt ly^'" ?^<^^ay- A number of bowls of broken pipes are inserted in the clav: in r«.?n!i ?K f'-a^ments are placed upright, to form the sides of the cylinder. The ribs r. Kv 'i^°"^^''^^' ^'"/=»^ ^o™ the flues, are made in the same way, as well as the dome iJnnlZl'^r T'"''-^ !u^ J^V"^"*^ ^^^^ T^ b^ "^ade very strong, and yet so thin as to a!^n P. T. ^^ "" ^^^ ^'"''^'"'^ * "^^^^'^^^ fi'-e to heat it, while it is not apt to spUt ?„r,c •• .Tk^ ^'P^' ^/^ arranged within, as shown in the figure, with their bowls rest- ing agamst the circumference, and their ends supported on circular pieces of clay r, which ^ln^\u^ '" ^''m ^'^""■t ^""^ ^^*' purpose. Six small ribs are made to project inwards all round the crucible, at the proper heights, to support the different ranges of pipes, withou navmg so many resting on each other as to endanger their being crushed by the weight. withii'sTr q Innr'^'TT' u"' ^"'"^T V^ ^^"^^''^ ^^ ^'^''^ ^' ^^^O pipes, all baked r»r.l«n! T ? !e ^^t-^'^ ^^'"^ gradually raised, or damped if occasion be, by a plate partially slid over the chimney top. > / " I'^^^c TODDY, Sura, 3fee.ru, sweet juice.— The proprietors of cocoa-nut plantations m the peninsula of India, and in the Island of Ceylon, instead of collecting a crop of nuS stalk' Wh^'^h^'!? produce of the trees by extracting sweet juice from the flowed w?fh o flowering branch is half shot, the toddy-drawers bind the stock round With a yming cocoa-nut leaf in several places, and heat the spadix with a short baton of S-a ^o^^o^^fheT^^^^^ ^ff^ '\^:^s.::i:^-:\^^ tt::i rjy thVE^^pltTc^^^^ l^-" '- -'^-'^ -^- '> ^^ --^- ^^^i"^-> w^ieS A tlt''j!!''r '' ^^^f " ^T '^^ '^"""P ^^'^y* ^"'^ *^« to^'Jy « removed twice a day. h^. „? ; K. ^'"J'^Vf^tly Pushes out a new spadix once a month; and after each spadS t^^ns to bleed. It continues to produce freely for a month, b^ which time another S ready to supply its place. The old spadix continues to give a little juice for another ft ^„^.^i!'^''^'^ '' "'^"*'''^' i^^ ^^^' '^-'^ ^"-^ sometimes two pots attached to a tr^ dnce .Z' K f""''. T'"- ^^'^ "^ ^^'""'^ 'P^^'*^^^' '^ *"«^^ t« ^row, would pro- duce a bunch of nuts from two to twenty. Trees in a good soil produce twelve thr.fvK" '\'y'^'^,^^' ^^^!» ^r ^""^^'^^^y situated, they%ften do Z gTve mor! 1 tree daUv" '• "^ '^ ""^ ''^ ^"^^''^ P^°'' °^ ^^^^ ^^ sometimes yielded b^ ^;Ji*'*^'^^K '^ "V"^^ '° demand as a beverage in the neighborhood of villages, esoe- Zll^Z^""" ^^'T^^^'oops are stationed! When it is drunk before simrUe it is t cool delicious, and particularly wholesome beverage; but by eight or nia^ o'clock fe^. mentation has made some progress, and it is then highly intoxicating % lULlJ, 18 a brownish-red balsam, extracted from the stem of the Mvroxilon tolmferum, a tree which grows in South America. It is compo ed of ISin oil and benzoic acid Having an agreeable odor, it is sometimes Ssed in perfumery ''^^^^:^:X^t;i^ ^- -^-^ ^-^ --- 1 knotVoi ^^^^"°^^^^- ^Jo?;f ^^1 ??^^' !^\^''"i^ ^^ "'^ Dlpterix odorata, affords a concrete crystalline tTon tth' a cthTt^^^^^^^^^^^^^ ^^ ^^^ F--'-- I^ - exTr^cfedTy d^g^^^ «r.JKi. *^^^,*'^'' 7'»<^l^ dissolves the stearoptene and leaves a fat oil It has an Sgher llLl^'"' ""' " "^^" ^^^^ ^' '^ '-^'^'^ -' 1220 Fahrenhef^ and volatfle at mfn^tlken^^om'Jhe^fi^ ^^^ ^« ««^«'"^ «W™te tinctares mast U Almost all IZZ^TttZni'^'T^ -dissolv^rcopa^r '" " """^ "' ^'™""='' «.pal, before adding the oil of tureen n^K'T"'"''.'? '» """''ine the dryin^ oil with th. t»rpe„t.„e „„bi„es very readUyTvUh ?u ' d "' '", ""' '!"' "^ "islaken Cl „" oU of ra^t Se""' '""""'^^ '" " leSs by'Sr'"r7''' "«'.''«"e„s the vrrSi.:^ ""^ "rying the proporlioos of the inTe,);.™.. .J"'^"- "s consistence may be varie,) h. d".^ "PO" fe walls of ^ereuLfel" aT P^p^ i teXT'fl'e^i'''^ «-?"-- The Jfeshness at the present ee months. The magnesia will absorb alJ the ac J li/^"'*''? ^« settle for at least ""^ **''** *«d mucilage from the oil, and VAllNISH. 883 fill to the bottom of the cistern, leaving the oil clear and transparent, and fit for nae. Recollect, when the oil is taken out, not to disturb the bottoms, which are only fit foi black paint. GENERAL OBSERVATIONS AND PRECAUTIONS TO BE OBSERVED IN MAKING VARNISHES. Set on the boiling-pot with 8 gallons of oil ; kindle the fire ; then lay the fire in the gum-furnace; have as many 81b. bags of gum-copal all ready weighed up, as will be wanted; put one 81b. into the pot, put fire to the furnace, set on the gum-pot; in three minutes (if the fire is brisk) the gum will begin to fuse and give out its gas, steam, and acid; stir and divide the gum, and attend to the rising of it, as before directed. Eight pounds of copal take in general from sixteen to twenty minutes in fusing, from the beginning till it gets clear like oil, but the time depends very much on the heat of the fire, and the attention of the operator. During the first twelve minutes, while the gum is fusing, the assistant must look to the oil, and bring it to a smart simmer ; for it ought to be neither too hot, nor yet loo cold, but in appearance beginning to boil, which he is strictly to observe, and, when ready, to call out, " Bear a hand !" Then immediately both lay hold of a handle of the boiling-pot, lift it right up, so as to clear the plate, carry it out and place it on the ash-bed, the maker instantly returning to the gum-pot, while the assistant puts three copper ladlefiils of oil into the copper pouring-jack, bringing it in and placing it on the iron plate at the back of the gum-pot to keep hot until wanted. When the maker finds the gum is nearly all completely fused, and that it will in a few minutes be ready for the oil, let him call out, " Ready oil !'* The assist- ant is then to lift up the oil-jack with both hands ; one under the bottom and the other on the handle, laying the spout over the edge of the pot, and wait until the maker calls out, " Oil !" The assistant is then to pour in the oil as before directed, and the boiling to be continued until the oil and gum become concentrated, and the mixture looks clear on the glass; the gum pot is now to be set upon the brick-stand until the assistant puts three more ladlefuls of hot oil into the pouring-jack, and three more into a spare tin for the third run of gum. There will remain in the boiling-pot still 3| gallons of oil. Let the maker put his right hand down the handle of the gum-pot near to the side, with his left hand near the end of the handle, and with a firm grip lift the gum-pot, and deliberately lay the edge of the gum-pot over the edge of the boiling-pot until all its contents run into the boiling pot. Let the gum-pot be held, with its bottom turned upwards, for a minute right over the boiling-pot. Observe, that when- ever the maker is beginning to pour, the assistant stands ready with a thick piece of old carpet, without holes, and sufficiently large to cover the mouth of the boiling-pot should it catch fire during the pouring, which will sometimes happen if the gum-pot is very hot ; should the gum-pot fire, it has only to be kept bottom upwards, and it will go out of itself; but if the boiling-pot should catch fire, during the pouring, let the assistant throw the piece of carpet quickly over the blazing pot, holding it down all round the edges ; in a few minutes it will be smothered. The moment the maker has emptied the gum-pot, he throws into it half a gallon of turpentine, and with the sivish immediately washes it from top to bottom, and instantly empties it into the flat tin jack : he wipes the pot dry, and puts in 8 pounds more gum, and sets it upon the furnace ; pro- ceeding with this run exactly as with the last, and afterwards with the third run. There will then be 8 gallons of oil and 24 pounds of gum in the boiling-oot, under which keep up a brisk strong fire until a scum or froth rises and covers allthe surface of the contents, when it will begin to rise rapidly. Observe, when it rises near the rivets of the handles, carry it from the fire, and set it on the ash-bed, stir it down again, and scatter in the driers by a little at a time ; keep stirring, and il the frothy head goes down, put it upon the furnace, and introduce gradually the remainder of the driers, always carrying out the pot when the froth rises near the" rivets. In general, if the fire be good, all the time a pot requires to boil, from the time of the last gum being poured in, is about three and a half or four hours ; but time is no criterion for a beginner to ju^dge by, as it may vary according to the weather, the quality of the oil, the quality of the gum, the driers, or the heat of the fire, &c.; therefore, about the third hour of boihng, try it on a bit of glass, and keep it boiling until it feels strong and stringy be- tween the fingers; it is then boiled sufficiently to carry it on the ash-bed, and to be stirred down until it is cold enough to mix, which will depend much on the weather, vary- ing from half an hour, in dry frosty weather, to one hour in warm summer weather. Previous to beginning to mix, have a sufficient quantity of turpentine ready, fill the pot, and pour in, stirring all the time at the top or surface, as before directed, until there are fifteen gallons, or five tins of oil of turpentine introduced, which will leave it quite thick enough if the gum is goo«l, and has been well run; but if the gum was of a weak quality, and has not been well fused, there ought to be no more than twelve gallons of turpentine mixed, and even thai may be too much. Therefore, when twelve gallons of turpentine have been introdused, have a flat saucer at hand, ad pour into it 884 VARNrSH. a portion of the varnish, and in two or three minutes it will show whether it is too thick ; if not sufficiently thin, add a little more turpentine, and strain it ofl" quickly. As soon as the whole is stored away, pour in the turpentine washings, with which the gum-pots have been washed, into the boiling-pot, and with the swish quickly wash down all the varnish from the pot sides ; afterwards, with a large piece of woollen rag dipped in pumice-powder, wash and polish every part of the inside of the boiling-pot, performing the same operation on the ladle and stirrers ; rinse them with the turpen- tine washings, and at last rinse them altogether in clean turpentine, which also put to the washings ; wipe dry with a clean soft rag the pot, ladle, stirrer, and funnels, and lay the sieve so as to be completely covered with turpentine, which will always keep it Irom gumming up. The foregoing directions concerning running the gum, and pouring in the oil, and also boiling ofl' and mixing, are, with very little difference, to be observed in the making of all sorts of copal varnishes, except the differences of the quantities of oil, gum, &c., which will be found under the various descriptions by name, which will be hereafter described. The choice of linseed oil is of peculiar consequence to the varnish-maker. Oil from fine full-grown ripe seed, when viewed in a vial, will appear limpid, pale, and brilliant; it is mellow and sweet to the taste, has very little smell, is specifically lighter than im- pure oil, and, when clarified, dries quickly and firmly, and does not materially change the color of the varnish when made, but appears limpid and brilliant. Copal varnishes for fine paintings^ ^c. — Fuse 8 pounds of the very cleanest pale African gum copal, and, when completely run fluid, pour in two jjallons of hot oil, old measure; let it boil until it will string very strong; and in about fifteen minutes, or while it is yet very hot, pour in three gallons of turpentine, old measure, and got from the top of a cistern. Perhaps, during the mixing, a considerable quantity of the turpentine will escape ; but the varnish will be so much the brighter, transparent, and fluid; and will work freer, dry more quickly, and be very solid and durable when dry. After the varnish has been strained, if it is fbund too thick, before it is quite cold, heat as much turpentine, and mix with it, as will bring it to a proper consistence. Cabinet varnish — Fuse 7 pounds of very fine African gum copal, and pour in half a gallon of pale clarified oil ; in three or four minutes after, if it feel stringy, take it out of doors, or into another building where there is no fire, and mix with it three gallons of turpentine ; afterwards strain it, and put it aside for use. This, if properly boiled, will dry in ten minutes ; but if too strongly boiled, will not mix at all with the turpen- tine; and somefiines, when boiled with the turpentine, will mix, and yet refuse to incor- porate with any other varnish less boiled than itself: therefore it requires a nicety which is only to be learned from practice. This varnish is chiefly intended for the use of ja- panners, cabinet-painters, coach-painters, &c. Best body copal varnish for coach-makersy 4rc. — This is intended for the body parts of coaches and other similar vehicles, intended for polishing. Fuse 8 lbs. of fine African gum copal ; add two gallons of clarified oil (old measure) ; boil it very slowly for four or five hours, until quite stringy; mix with three gallons and a half of turpentine ; strain off, and pour it into a cistern. As they are too slow in dry- ing, coach-makers, painters, and varnish-makers, have introduced to two pots of the ore- ceding varnish, one made as follows : — 8 lbs. of fine pale gum animej I 3h gallons of turpentine. 2 gallons of clarified oil; ( "To be boiled four hours. Quick drying hodg copal varnish, for coaches, ^c. (1.) 8 lbs. of the best African copal ; 2 gallons of clarified oil ; J lb. of dried sugar of lead; 3| gallons of turpentine. Boiled till stringy, and mixed and strained. To be mixed and strained while hot into the other pot. These two pots mixed togetn«» will dry in six hours in winter, and in four in summer ; it is very useful for varnishlBf old work on dark colors, &c. (2.) 8 lbs. of fine gum anime; 2 gallons of clarified oil ; \ lb. of white copperas ; 3§ gallons of turpentine. Boiled as before. Best pale carriage varnish, (1.) 8 lbs. 2d sorted African copal; 2| gallons of clarified oil. Boiled till very stringy. I lb. of dried copperas ; J lb. of litharge; 5| gallons of turpentine. Strained ft.r.. (2.) 8 lbs. of 2d sorted gum anim^ { 24 gallons of clarified oil ; f lb. of dried sugar of lead ; I lb. of litharge; 5^ gallons of turpentine. Mix this to the first while hot. VARNISH. 885 This varnish will dry hard, if well boiled, in four hours in summer, and in six ia win. ler. As the name denotes, it is intended for the varnishing of the wheels, springs, and carriage parts of coaches, chaises, &c. ; also, it is that description of varnish which is generally sold to and used by house-painters, decorators, &,c. ; as from its drying quality an^. strong gloss, it suits their general purposes well. 8 lbs. of 2d sorted gum anime ; 2| gallons of fine clarified oil ; 5^ gallons of turpentine ; i lb. of litharge ; Second carriage varnish. I lb. of dried sugar of lead; J lb. of dried copperas. Boiled'and mixed as before. Wainscot varnish. 8 lbs. of 2d sorted gum anime ; 3 gallons of clarified oil ; i lb. of litharge j J lb. of dried sugar of lead ; 5k gallons of turpentine. To be well boiled until it strings very strong, and then mixed and strained. Mahogany varnish is made either with the same proportions, with a little darker gum ; otherwise it is wainscot varnish, with a small portion of gold size. Black japan is made by putting into the set-pot 48 pounds of Naples, or any other of the foreign asphaltums, (except the Egyptian.) As soon as it is melted, pour in 10 gal- lons of raw linseed oil; keep a moderate fire, and fuse 8 pounds of dark gum anime in tlie gum-pot ; mix it with 2 gallons of hot oil, and pour it into the set-pot. Afterwards fuse 10 pounds of dark or sea amber in the 10 gallon iron pot; keep stirring it while fusing ; and whenever it appears to be overheated, and rising too high in the pot, lift it from the fire for a few minutes. When it appears completely fused, mix in 2 gallons of hot oil, and pour the mixture into the set-pot ; continue the boiling for 3 hours longer, and during that thne introduce the same quantity of driers as before directed ; draw out the fire, and let it remain until morning ; then boil it until it rolls hard, as before directed ; leave it to cool, and afterwards mix with turpentine. Pale amber varnish. — Fuse 6 pounds of fine picked very pale transparent amber in the gum-pot, and pour in 2 gallons of hot clarified oil. Boil it until it strings very strong. Mix with 4 gallons of turpentine. This will be as fine as body copal, will work very free, and flow well upon any work it is applied to; it becomes very hard, and is the most durable of all varnishes ; it is very excellent to mix in copal varnishes, to give them a hard and durable quality. Observe; amber varnish will always require a long time be- fore it is ready for polishing. Best Brunswick black. — In an iron pot, over a slow fire, boil 45 pounds of foreign asphaltum for at least 6 hours ; and during the same time boil in another iron pot 6 gal- lons of oil which has been previously boiled. During the boiling of the 6 gallons, intro- duce 6 pounds'of litharge gradually, and boil until it feels stringy between the fingers; then ladle or pour it into the pot containing the boiling asphaltum. Let the mixture boil until, upon trial, it will roll into hard pills ; then let it cool, and mix it with 25 gallons of turpentine, or until it is of a proper consistence. Iron-work black. — Put 48 pounds of foreign asphaltum into an iron pot, and boil for 4 hours. During the first 2 hours, introduce 7 pounds of red lead, 7 pounds of litharge, 3 pounds of dried copperas, and 10 gallons of boiled oil ; add 1 eight-pound run of dark gum, with 2 gallons of hot oil. After pouring the oil and gum, continue the boiling two hours, or until it will roll into hard pills like japan. When cool, thin it off with thirty gallons of turpentine, or until it is of^a proper consistence. This varnish is intended for blacking the iron-work of coaches and other carriages, &c. Jl cheap Brunswick black. — Put 28 pounds of common black pitch, and 28 pounds of common asphaltum made from gas tar, into an iron pot ; boil both for 8 or 10 hours, which will evaporate the gas and moisture ; let it stand all night, and early next morn- ing; as soon as it boils, put in 8 gallons of boiled oil ; then introduce, gradually, iO pounds of red lead, and 10 pounds of litharge, and boil for 3 hours, or until it will roll very hard. When ready for mixing, introduce 20 gallons of turpentine, or more, until of a proper consistence. This is intended for engineers, founders, ironmongers, &,c. ; it will dry in half an hour, or less, if properly boiled. Jxioms observed in the making of copal varnishes. — The more minutely the gum is run, or fused, the greater the quantity, and the stronger the produce. The more regular and longer the boiling of the oil and gum together is continued, the more fluid or free the varnish will extend on whatever it is applied to. When the mixture of oil and gum is too suddenly brought to string by too strong a heat, the varnish requires more than its just proportion of turpentine to thin it, whereby its oily and gummy quality is reduced, which renders it less durable ; neither will it flow so well in laying on. The greater proportion of oil there is used in varnishes, the less they are liable to crack, because the tougher and softer they are. By increasing the proportion of gum in varnishes, ■p*' 886 VARNISH. the thicker -will be the stratum, the firmer they will set solid, and the quicker they will dry. When varnishes are quite new made, and must be sent out for use before they are of sufficient age, they must always be left thicker than if they were to be kept the proper time. Varnish made from African copal alone possesses the most elasticity and transpa- rency. Too much driers in varnish render it opaque and unfit for delicate colors. Cop- peras does not combine with varnish, but only hardens it. Sugar of lead does combine with varnish. Turpentine improves by age; and varnish by being kept in a warm place. All copal or oil varnishes require age before they are used. Cmcluding observaliom,—A\\ body varnishes are intended and ought to have l\ lbs. cf gum to each gallon of varnish, when the varnish is strained off, and cold ; but as the thin- ning up, or quantity of turpentine required to bring it to its proper consistence, depends verj' much upon the degree of boiling the varnish has undergone, therefore, when Ihe gum and oil have not been strongly boiled, it requires less turpentine for that purpose ; whereas, when ihe gum and oil are very strongly boiled together, a pot of 20 gallons will require perhaps 3 gallons above the regular proportionate quantity ; and if mixin? the turpentine is commenced too soon, and the pot not sufficiently cool, there will be frequently above a gallon and a half of turpentine lost by evaporation. All carriage, wainscot, and mahogany varnish ought to have fully one pound of gum for each gallon, when strained and cold ; and should one pot require more than its proportion of turpentine, the following pot can easily be leA not quite so strongly boiled ; then it will require less turpentine to thin it up. Gold sizes, whether pale or dark, ought to have fully half a pound of good gum copal to each gallon, when it is finished ; and the best black japan, to have half a pound of eood gum, o> upwards, besides the quantity of asphaltum. Fine mattic, or picture varnish. — Put 5 pounds of fine picked gum mastic into a new four-gallon tin botile; get ready 2 pounds of glass, bruised as small as barley; wash it several times; afterwards dry it perfectly, and put it into the bottle with 2 gallons of tur- pentine that has settled some time ; put a piece of soft leather under the bung ; lay the tin on a sack upon ihe counter, table, or any thing that stands solid ; begin to agitate the tin, smartly rolling it backward and forward, causing the gum, glass, and turpentine, to work as if in a barrel churn for at least 4 hours, when the varnish may be emptied out into any thing sufficiently clean, and large enough to hold it. If the sum is not all dissolved, return the whole into the bottle, and agitate as before, until all the gum is dissolved ; then strain it through fine thin muslin into a clean tin botile: leave it uncorked, so that the air can get in, but no dust ; let it stand for 9 months, at least, before it is userl ; for the longer it is kept, the tougher it will be, and less liable to chill or bloom. To prevent mastic varnish from chillins, boil one quart of river sand with two ounces of pearl-ashes; afterwards wash the sand three or four times with hot water, straining it each time ; put the sand on a soup-plate to dry, in an oven ; and when it is of a good heat, pour half a pint of hot sand into each gallon of varnish, and shake it well for five minutes; it will soon settle, and carry down the moisture of the gum and turpentine, which is the general cause of mastic varnish chilling on paintings. Common mastic varnish. — Put as much gum mastic, unpicked, into the gurn-pot as may be required, and to every 2f pounds of ?um pour in 1 gallon of cold turpentine ; set the pot over a very moderate fire, and stir it with the stirrer; be careful, when the steam of the turpentine rises near the mouth of the pot, to cover it with the carpet, and carry it out of doors, as the vapor is very apt to catch fire. A few minutes' low h^eat will perfectly dissolve 8 pounds of gum, which will, with 4 gallons of turpentine, produce, when strain- ed, 4^ gallons of varnish; to which add, while yet hot, 5 pints of pale turpentine varnish, which improves the body and hardness of the mastic varnish. Crystal varnish, may he made either in the varnish-house, drawing-room, or parlor. Procure a bottle of Canada balsam, which can be had at any druggist's ; draw out the cork, and set the botile of balsam at a little distance from the fire, turning it round several times, until the heat has thinned it ; then have something that will hold as much as double the quantity of balsam ; carry the balsam from the fire, and, while fluid, mix it Jvith the same quantity of good turpentine, and shake them together until they are well incorpora- ted; in a lew days the varnish is fit for use, particularly if it is poured into a half-gallon glass or stone bottle, and kept in a gentle warmth. This varnish is used for maps, prints, charts, drawings, paper ornaments, &c. ; and when made upon a larger scale, requires only warming the balsam to mix with the turpentine. White hard spirit-of-wine varnish.— ?ui 5 pounds of gum sandarach into a four-gallon tin bottle, with 2 gallons of spirits of wine, 60 over proof, and agitate it until dissolved, exactly as directed for the best mastic varnish, recollecting, if washed glass is used, that it is convenient to dip the bottle containing the gum and spirits into a copperful of hot water every 10 minutes— the bottle to be immersed only 2 minutes at a time— which will greatly assist the dissolving of the gum ; but, above all, be careful to keep a firm hold over the cork of the bo»»le, otherwise the rarefaction will drive the cork out with tbt VARNISH. 887 foice of a shot, and perhaps set fire to the place. The bottle, every time it is heated, ought to be carried away from the fire ; the cork should be eased a little, to allow the rarefied air to escape ; then driven tight, and the agitation continued in this manner until all the gum is properly dissolved; which is easily known by having an empty tin can to pour the varnish into, until near the last, which is to be poured into a gallon mea- sure. If the gum is not all dissolved, leturn the whole into the four-gallon tin, and con- tinue the agitation until it is ready to be strained, when every thing ought to be quite ready, and perfectly clean and dry, as oily fins, funnels, strainers, or any thing damp, or even cold weather, will chill and spoil the varnish. After it is strained off, put into the varnish one quart of very pale turpentine varnish, and shake and mix the two well together. Spirit varnishes should be kept well corked ; they are fit to use the day after being made. Brown hard spirit varnish, is made by putting into a bottle 3 pounds of gum sandarach, with 2 pounds of shellac, and 2 gallons of spirits of wine, 60 over proof; proceeding exactly as before directed for the white hard varnish, and agitating it when cold, which requires about 4 hours* time, without any danger of fire; whereas, making any spirit varnish by heat is always attended with danger. No spirit varnish ought to be made either near a fire or by candle light. When this brown hard is strained, add one quart of turpentine varnish, and shake and mix it well : next day it is fit for use. The Chinese varnish, comes from a tree which grows in Cochin-China, China, and Siam. It forms the best of all varnishes. Gold lacker. — Put into a clean four-gallon tin, 1 pound of ground turmeric, 1| ounces of powdered gamboge, 3| pounds of powdered gum sandarach, f of a pound of shellac, and 2 gallons of spirits of wine. After being agitated, dissolved, and strained, add 1 pint ol turpentine varnish, well mixed. Red spirit lacker. 2 gallons of spirits of wine ; 1 pound of dragoi's blood; 3 pounds of Spanish annotto ; 3| pounds of gum sandarach; 2 pints of turpentine. Made exactly as the yellow gold lacker. Pale brass lacker, 2 gallons of spirits of wine ; 3 ounces of Cape aloes, cut small ; I pound of fine pale shellac ; 1 ounce gamboge, cut small. No turpentine varnish. Made exactly before. as But observe, that those who make lackers, frequently want some paler, and some darker, and sometimes inclining more to the particular tint of certain of the component ingredir ents. Therefore, if a four-ounce vial of a strong solution of each ingredient be prepared, a lacker of any tint can be produced at any time. Preparation of linseed oil for making varnishes. — Put 25 gallons of linseed oil into an iron or copper pot that will hold at least 30 gallons; put a fire under, and gradually in- crease the heat, so that the oil may only simmer, for 2 hours ; during that time the great- est part of its moisture evaporates; if any scum arises on the surface, skim it off, and put that aside for inferior purposes. Then increase the fire gradually, and sprinkle in, by a little at a lime, 3 lbs. of scale litharge, 3 lbs. of good red lead, and 2 lbs. of Turkey umber, all well dried and free from moisture. If any moist driers are added, they will cause the oil to tumefy ; and, at the same time, darken it, causing it to look opaque and thick, ropy and clammy, and hindering it from drying and hardening in proper time ; be- sides, it will lie on the working painting like a piece of bladder skin, and be very apt to rise in blisters. As soon as all the driers are added to the oil, keep quietly stirring the driers from the bottom of the pot ; otherwise they will burn, which will cause the oil to blacken and thicken before it is boiled enough. Let the fire be so regulated that the oil shall only boil slowly for three hours from the time all the driers were added; if it then ceases to throw up any scum, and emits little or no smoke, it is necessary to test its tem- perature by a few quill tops or feathers. Dip a quill top in the oil every two minutes, for when the oil is boiled enough, the quill top will crackle or curl up quite burnt; if so, draw out the fire immediately, and let the oil remain in the pot at least from 10 to 24 hours, or longer if convenient, for the driers settle much sooner when the oil is It ft to cool in the pot, than when it is immediately taken out. Poppy oil. — Into four pints of pure soft water, put two ounces of foreign white vitriol g warm the water in a clean copper pan, or glazed earthen jar, until the vitriol is dissolv- ed ; pour the mixture into a clean glass or stone bottle, large enough to contain three gallons; then add to the solution of vitriol one gallon and a half of poppy oil, cork and agitate the bottle regularly and smartly for at least two hours ; then pour out the contents into a wide earthenware dish : leave it at rest for eight days, when the oil will be clea» and brilliant on the surface, and may be taken off with a spoon or flat* skimmer, and pu* up in a glass bottle and exposed to the light, which in a few weeks renders the oil exceed- ingly limpid and colorless. 888 VENTILATION. VENTILATION. 889 iVi<^o^/ or oil of walnutu, is extracted by expression ; and that which is extracted without healv is certainly the most pale, pure, and nutritive seasoning, and retains an exquisite taste of the fruit That designed for the arts is of inferior quality, and is plentifully imported to us from France; the heat it undergoes in its ton-efaction, pre- vious to its expression, disposes it to dry more quickly than that expressed by the cold process; but, at the same time, the heat, though it frees it from its unctuous quality gives It more color. When it has been extracted by the cold process, it may be pre- pared m the same way as directed for the poppy oil. In the above article I have retained the workmen's names— gum, white vitriol Ac. instead of resin, sulphate of zinc, f his furnace, all the vitiated current to a mere gas-pipe or drift, and direct it wholly hrough the dumb fur- nace. During a practice of twenty years. Mr. Buddie has not met with any accident IB consequence of a defect in the stoppings preventing the complete division of the air. The engineer has it thus within his power to detach or insulate those portions of the mine in which there is a great exudation of gas, from the rest ; and, indeed, he is con- tinually making changes, borrowing and lending currents, so to speak ; sometimes laying one division or panel upon the one air-course, and sometimes upon the other, just to suit the immediate emergency. As soon as any district has ceased to be dangerous, by the exhaustion of the gas-blowers, it is transferred from the foul to the pure air course, where gunpowder may be safely used, as also candles, instead of Davy's lamps, which give less light. The quantity of air put down into the Wallsend ».olliery, at the timeof the last dreadful iccident, l8th June, 1835, was not less than 5000 cubic feet per minute, whence it has been justly inferred that the explosion was caused by the rashness of a wasteman carrying a light through a door into a foul drift. Till the cutting out of the pillars commences (see the risrht end of the diagram), the ▼enlilation of the several passages, boards, &c., may be kept perfect, supposing the working extended no furlher than o, or b; because, as long as there are pillars standing^ every passage may be converted into an air-conduit, for leading a current of air in any direction, either to c, the burning, or d, the dumb furnace. But the first pillar that is removed deranges the ventilation at that spot, and takes away the means of carrying the air into the further recess towards c. In taking: out the pillars, the miners always work to windward, that is to say, against the stream of air; so that whatever gas may be evolved shall be immediately carried ofl' from the people at work. When a range of pillars has msSBm 890 VENTILATION. been removed, as at 4 «,/, no power remains of dislodging the gas from the section Of the mine beyond a, b; and as the pillars are successively cut away to the left hand of the line a, b, the size of the poaf, or void, is increased. This vacuity is a true gas-holder, or reservoir continually discharging itself at the points a, fC L into the circulating current, to be carried off by the gas-pipe drift at the dumb furnace, but not to be suffered ever to come in contact with flame of any description. The next range of working is the line of pillars to the left of a. 6 ; the coal having been entirely cleared out of the space to the right, where the place of the pillars is marked by dotted lines. The roof in the waste soon falls down, and gets fractured up to the next seam of coal called the yard-coal seam, which, abounding in gas, sends it down in laree ^^e^STOVR immense gasometer, or goaf below, continually replenished, . '^f^^ ?f« two general plans in use for at once diffusing heat and renewing the air m extensive bii'Idings, which plans differ essentially in their principles, modes of action, and effects. The oldest, and what may be called, the vulgar method, consists in planting stoves in the pas-ages or rooms to give warmth in cold weather, and in construetinS large and lofty chimney-stalks, to draw air in hot weather out of the house by suctiob. «o to speak, whereby fresh air flows in to maintain, though imperfectly, an equilibrium of pressure. In apartments, thus warmed and ventilated, the atmosphere is necessarily rarer than it is out of doors, while, in cold weather, the external air rushes in at every opening and crevice of door, window, or chimney— the fruitful source of indisposition to the inmates. *^ The evils resulting from the etove-heating and air-rarefying system were, a few years *^v,'-TT^'^^^ ^^™^' '" * ^^^^^ ^^^^ before the Royal Society,* and afterward published in several scientific and technological journals. It is there said that the ob servations of Saussure, and other scientific travellers in mountainous regions, demon- strate how difficult and painful it is to make muscular or mental exertions in rarefied air. Even the slight rarefaction of the atmosphere, corresponding to a low state of the bar- ometer, at the level of the sea, is sufficient to occasion languor, lassitude, and uneasi- ness, m persons of delicate nerves ; while the opposite condition of increased pressure as indicated by a high state of the barometer, has a bracing effect upon both body and mmd. Thus, we see how ventilation, by the powerful draught of a high chimney-stalk as It operates by pumping out, exhausting and attenuating the air, may prove detriment talto vivacity and health ; and how ventilation, by forcing in air with a fan or a pump, IS greatly to be preferred, not only for the reason above assigned, but because it pre' vents all regurgitation of foul air down the chimneys, an accident sure to happen in the former method. Genial air thrown in by a fan, in the basement story of a building also prevents the stagnation of vapors from damp and miasmata, which lurk about the loundation of buildings and in sewers, and which are sucked in by the rarefyin*' plan. Many a lordly mansion is rendered hardly tenantable from such a cause, durin«' certain vicissitudes of wind and weather. The condensing plan, as executed by the engineers, Messrs. Easton and Amos, at the Ketorm Club House, consists of a large fan, revolving rapidly in a cylindrical case, and is capable of throwing 11,000 cubic feet of air per minute, into a spacious subterranean tunnel, under the basement story. The fan is driven by an elegant steam-engine, worked on the expansion principle, of 5 horses' power. It is placed in a vault, under the flag- pavement, in front of the building ; and as it moves very smoothly, and burns merely cinders Irom the house fires, along with some anthracite, it occasions no nuisance of any kind. The steam of condensation of the engine supplies 3 cast-iron chests with the requisite heat for warming the whole of the building. Each of these c^iests is a cube 01 3 feet externally, and is distributed internally into 7 parallel cast-imn cases, I486 1487 VENTILATION. 891 r ^ i 1485 —^ •1 ir — — —m- ii ); :lL. ,; !i IJ ■1 i- ■1 = — i: ^^ISr-^"^^^^^ ^^v\s£?.- n.-f„%To„t-u.Tru5rJi5ri each about 8 inches wide, which are separated by parallel alternate spaces, of the same width, for the passage of the air transversely, as it is impelled by the fan. Mg. 1485 is a transverse vertical section of the steam chest, for heating the air; ^g. 1486 is a plan of the same; and Jig. 1487 is a perspective view, showing the outside casing, also the pipe a, for admitting the steam, and the stop-cock 6, for allowing the condensed water to escape. This arrangement is most judicious, economizing fuel to the utmost degree; becatisfl the steam of condensation which, in a Watt's engine, would be absorbed and carried off by the air-pump, is here turned to good account, in warming the air of ventilation du- ring the winter months. Two hundred weight of fuel suffice for working this steam- engine during twelve hours. It pumps water for household purposes, raises the coals to the several apartments on the upper floors, and drives the fan ventilator. The air, in flowing rapidly through the series of cells, placed alternately between the steam- cases, can not be scorched, as it is generally with air stoves ; but it is heated only to the genial temperature of from 75° to 85** Fahr., and it thence enters a common chamber of brickwork in the basement story, from which it is let off into a series of distinct flues, governed by dialled valves or registers, whereby it is conducted in regulated quantities to the several apartments of the building. I am of opinion that it would not be easy to devise a better plan for the purpose of warming and ventilating a large house ; and I tm only sorry to observe, that the plan projected by the engineers has been injudiciously counteracted in two particulars. The first of these is, that the external air, which supplies the fan, is made to traverse a great heap of coke before it can enter that apparatus, whereby it suffers such friction as materially to obstruct the ventilation of the house. The following experiments, which I made recently upon this point, will place the evil in a proper light : Having fitted up Dr. Wollaston's differential barometer, as an anemometer, with f il, of specific gravity 0*900 in one leg of its syphon, and water of 1*000 in the other, covered with the said ofl .n the two cisterns at top, I found that the stream of air produced by the fan, in a ce» tain pait of the flue, had a velocity only as the number 8, while the air was drawn through the coke, but that it had a velocity in the same place as the number 11, when- ever the air was freely admitted to the fan by opening a side door. Thus, three elevenths, both of the ventilating and warming effect of the fan, are lost. I can not divine any good reason for making the members of the Reform Club breathe an atmo- sphere, certainly not improved, but most probably vitiated, by being passed in a moist state through a porous sulphurous carbon, whereby it will tend to generate the two deleterious gases, carbonic oxide and sulphuretted hydrogen, in a greater or less de- gree. It is vain to allege that these gases may not be discoverable by chemical analy- sis — can the gaseous matters, which generate cholera, yellow fever, or ague, be detected by chemical reagents ? No, truly ; yet every one admits the reality of their specific virus. I shoiild propose that the air be transmitted through a large sheet of wire-cloth before it reaches the fan, whereby it would be freed from the grosser particles of soot that pollute the atmosphere of London. The wire-cloth should be brushed every morning The second particular, which counteracts in some measure the good effects of the fan in steam ventilation, is the huge stove placed in the top story of the building. This potent furnace, consuming, when in action, 3 cwt. of coals per day, tends to drawdown foul air, for its own supply, from the chimneys of the adjoining rooms, and thus to impede the upward current created by the fan. I have measured, by Dr. Wollaston's differential barometer, the ventilating influence of the said furnace stove, and find it to be perfectly insignificant— nay, most absurdly so— when compared with the fan, as to the quantity of fuel which each requires per day. The rarefaction of air in the stove chamber, in reference to the external air, was indicated by a quarter of an inch differ- ence of level in the legs of the oil and water syphon, and this when the door of the stove-room was shut, as it usually is ; the tube of the differential barometer being inserted in a hole in the door. The fan indicates a ventilating force equal to 2 inches of the water syphon, which is 20 inches of the above oil and water syphon, and there- fore 80 times greater than that of the stove furnace ; so that, taking into view the smaller quantity of fuel which the fan requires, the advantage in ventilation, in favor of the fan, m the enormous ratio of 120 to 1, at the lowest estimate. The said stove, in the attic, seems to me to be not only futile, but dangerous. It is a huge rectangular cast-iron chest, having a large hopper in front, kept full of coals, and il is contracted above into a round pipe, which discharges the burnt air and smoke into a series of hori- zontal pipes of cast-iron, about 4 inches diameter, which traverse the room under the ceiling, and terminate in a brick chimney. In consequence of this obstruction, the draught through the furnace is so feeble, that no rush of air can be perceived in its ash- pit, even when this is contracted to an area of 6 inches square : nav, when the ash-pit was momentarily luted with bricks and clay, and the tube of the differential barometer 892 VENTILATION. was introduced a little way under the grate, the level of the oil and water svDhon in that instrument was d.splaeed by no more than one-tenth of an ineh. which is itone W dredth of an inch of water-a most impotent effect under a daily consumption of 3 c^. of coals. In fact this stove may be fitly styled an incendiary coaUdev^rn as it has already set fire to the house; and though now laid upon a new floor of CTifters ^d stone flags, it stUl oflers so much danger from its outlet iron pipes, shouirthey become pited from the combustion of charcoal deposited in them, that I think no premium 7 insurance adequate to cover the imminent risk of fire. The stove being, theSe a superfluous and dangerous nuisance, should be turned out of doors as spVedily as pos! tt\y.^VT\T'T^ ^^^' ?^"«^^"«^ i« the basement story, can not bemuch kss Wurtenances ^^^"°^-^"-^^°^' ^^^^ ^^ '^'^ '^y ^ff^^tual warming and ventllaUng .J If ^^^ J^\? ^"^ "^^f'^^' ^^""^ ^^^ ^y«^^"^ o^ ^^^ting and ventilating apparatus, con- ■^ucted by Messrs. Easton and Amos, in the Reform Club House, offers one s^kT"; and peculiar advantage It may be modified at little expense, so as to become the read? Sure o? 10 20"'^^' """^ '""LT'"''' ^°^.-^'>"^' refreshingcurrentsof air,at atem! ?hTl ? ?: u' ? ' *'''.^7'' ^^ ^^"^^""^ ^°^^^ that of atmosphere. An apparatus of ? • ^^ture attached to the houses of parliament and courts of law, would prove an in- estimable blessing to our legislators, lawyers, judges, and juries. Of sudi coofiJ a very gentle stream would suffice to make the molt crowded apartments eom?ortrble J^&:l'd"roor"' ''' ''''*' °' ^'"^ '^^^^^ "^^^ ^^^^^ «^-"^ throughTdooi:; -«?ii' J^tK-^"^''r ^^ ^ • ""^H^ *'°'^. ^^"^^ ^^' ^'^^^ '^^"^ ^«>- the well-being of the sentient and breathing functions of man in the public buildings of the metropolfs, notwithstand. ^ZZ^T%iT'\^^'T^^'''^ ""^ ^^«*"^'«'^ «^ "^^^"1 knowledge. Almost a^^^^^^^^ churches are filled on Sundays with stove-roasted air; and even the House of Commons has Its atmosphere exhausted by the suction of a huge chimney-stalk, with a furnace equal, I 13 said to that of a 40-horse steam-boiler. To gentlemen plunged in ir m Sf the'da?:'" ''''^''^''^^'^''"^^' and terseness of expression can hardly be toe^Jd« Nearly seven years have elapsed since I endeavored to point public attention to thin important subject in the following terms : « Our legislatoS^ wh^n bewa" ago, the fate of their fellow-creatures, doomed to breathe the polluted air of a facto^ were httle aware how superior the system of ventilation adopSU many co"onS was to that employed for their own comfort in either house of parliament! The eTi ! neers cf Manchester do not, like those of the metropolis, trust for a sufficient suppIv of I^fftZ: ?r^ ''T'*'^ ^^?^'° ^^^'"^^^ physically created in the atmosphere by^^^^ difference of temperature excited by chimney-draughts, because they know them LhP ineffectual to remove with requisite rapidit/, the dense carboniVacTd gas gener^t^ bv many hundred powerful lungs."* At page 382 of the work just quoted, S^ ^ exact drawing and description of the factory ventilatin- fan On the 6th of June, 1836, I took occasion again, in a paper read before the Roval Society, upon the subject of the malaria which then prevailed in the customhouse to investigate the principles of ventilation by the fan, and to demonstrate, ^a numerous tram of experiments the great preference due to it, as to effect, economy, and rmfort over chimney-draught ventilation. Yet at this very time, the litter Cs^oWecUonabVe Abou7?h;" r^'"'' f T'''^''^^^' «Po^ ^ colossal scale, for the H?use of Commons About the same period, however, the late ingenious Mr. Oldham, engineer of the^ank of England, mounted a mechanical ventilator and steam-chest heater f^r supply int a copious current of warm air to the rooms of the engraving and prin L- depar^meits'of that establishment. Instead of a fan, Mr. Oldham^-mployed a farge pump^o forc^^^^^^^ Znf'rt 1^%'t'?^'I '!"^ ^^ ^'' steam-chest. He had introdu^ced a siiiuar system into the bank of Ireland about ten years before, which is now in full action About two years ag^ Messrs. Easton and Amos were employed to ventilate the letter earners' and inland office departments of the general post-office, of whththe^ spnere was rendered not only uncomfortable but insalubrious by the numerous iT lights required there in the evenings. This task has been execuKo tLTnTe s^^^^^ faction of their employers, by means of fans driven by steam-engne power The saS ba^k^r/r^'f '^^r°''' '^" '^"^^ '''^'' ^ ''' «^ machinery simfla? to tCer'ect Jd at the ^ndn5t ?f^^''^>' rj"""-"^ ?^ ventilating the bank of Vienna. They are Justly enmled to the credit of having been the first to execute, in all its bearin4 the sjstem whirrs^^ru^r^^^^^ As fans of sufficient size, driven by steam powe? with sufficient velocity to warm in winter, and ventilate at all times, the most extensive buildings, may be Sed upon the * Philosophy of ManufHctures, p. 380. published by diaries Knight-London, 1835. m VENTILATION. 89o principles above described, without causing any nuisance from smoke, it is be hoped that the Chapel of Henry VII. will not be desecrated by having a factory Vesuvius reared in its classical precincts, and that the noble pile of architecture of the new houses of parliament will not be disfigured with such a foul phenomenon. ^ The cheering and bracing action of condensed air, and the opposite effects of rarefied air upon human beings, formed the subject of several fine physiological experiments, made a few years ago by M. Junot, and described by him in the ninth volume of the Archives Generales de Medecine : " When a person is placed,'* says he, " in condensed air, he breathes with a new facility ; he feels as if the capacity of his lungs was en- larged ; his respirations become deeper and less frequent ; he experiences, in the course of a short time, an agreeable glow in his chest, as if the pulmonary cells were becoming dilated with an elastic spirit, while the whole frame receives, at each inspiration, fresh vital impulsion. The functions of the brain get excited, the imagination becomes vivid, and the ideas flow with a delightful facility ; digestion is rendered more active, as after gentle exercise in the air, because the secretory organs participate immediately in the increased energy of the arterial system, and there is therefore no thirst." In rarefied air the effects on the living functions are just the reverse. The breathing is difficult, feeble, frequent, and terminates in an asthmatic paroxysm ; the pulse is quick and most compressible; hoemorrhages often occur, with a tendency to fainting; the secretions are scanty or totally suppressed, and at length apathy supervenes. These striking results obtained on one individual at a time, with a small experimental apparatus, have been recently reproduced, on a working scale, with many persons at once enclosed in a mining-shaft, encased with strong tubbing, formed of a series of large sheet-iron cylinders, riveted together, and sunk to a great depth through the bed of the river Loire, near Languin. The seams of coal, in this district of France, lie under a stratum of quicksand, from 18 to 20 metres thick (20 to 22 yards), and they had been found to be inaccessible by all the ordinary modes of mining previously prac- tised. The obstacle had been regarded to be so perfectly insurmountable, that every portion of the great coa^-basin, that extends under these alluvial deposites, though we| known for centuries, had remained untouched. To endeavor, by the usual workings, to penetrate through these semi-fluid quicksands, which communicate with the waters of the Loire, was, in fact, nothing less than to try to sink a shaft in that river, or to drain the river itself. But this difficulty has been successfully grappled with, through the resources of science, boldly applied by M. Triger, an able civil engineer. By means of the above frame of iron tubbing, furnished with an air-tight ante- chamber at its top, he has contrived to keep his workmen immersed in air, sufficiently condensed by forcing-pumps, to repel the water from the bottom of the iron cylinders, and thereby to enable them to excavate the gravel and stones to a great depth. The compartment at top has a man-hole door in its cover, and another in its floor. The men, after being introduced into it, shut the door over their heads, and then turn the stop-cock upon a pipe, in connexion with the condensed air in the under shaft. An equilibrium of pressure is soon established in the ante-chamber, by the influx of the dense air from below, whereby the man-hole door in the floor may be readily opened, to allow the men to descend. Here they work in air, maintained at a pressure of three atmospheres, by the incessant action of leathern-valved pumps, driven by a steam-eneine. While the densj air thus drives the waters of the quicksand, communicating with the Loire, out of the shaft, it infuses at the same time such energy into the miners, that they can easily excavate double the work without fatigue which they could do in the open air. Upon many of them the first sensations are painful, especially upon the ears and eyes, but ere long they get quite reconciled to the bracing element. Old asthmatic men become here effective operatives ; deaf persons recover their hearing, while others are sensible to the slightest whisper. The latter phenomenon proceeds from the stronger pulses of the dense air upon the membrane of the drum of the ear. Much annoyance was at first experienced from the rapid combustion of the candles, but this was obviated by the substitution of flax for cotton thread in the wicks. The temperature of the air is raised a few degrees by the condensation. Men who descend to considerable depths in diving-bells, experience an augmentation of muscular energy, similar to that above described. They thereby acquire the power of bending over their knees strong bars of iron, which they would find quite inflexible by their utmost efforts when drawn up to the surface. These curious facts clearly illustrate and strongly enforce the propriety of ventilating apartments by means of condensed air, and not by air rarefied with large chimney- draughts, as ha^ been hitherto most injudiciously, wastefully, and filthily done, in too many cases. As the subject of Tentilating and warnrting the public buildings in Liverpool, and particularly the new Custom-house, has been imder discussion, we extract from the Architectural Journal the following paper hv Mr. C. W. Williams. "Doctor Ure, in his inquiry into the modes of warming and ventilating, oUerves, m 894 VENUS. i 4 that the great principle of ventilation is, never to present the same portion of M*r twice over to the human lungs^ but to supply them at each fresh inspiration with pure aerial particles in a genial thermometric and hygrometric condition/ " Where heating is alone attended to, as in the case of heat conveyed by steam in metal pipes, it becomes necessary to provide currents of cold air, to supply the required continued change in the apartments for the purposes of ventilation. It is manifest then, that the best principle must be, first, to heat the required volume of fresh air and then to introduce it to the apartments to be heated and ventilated, instead of effecting this double object by two distinct processes. The modus operandi is as follows :— A body of pure air, of any required volume, and passing at any required velocity, is forced, by the aid of an air-condensing pump, into a chamber or chest, where it is heated in an ingeni- ously contrived, but extremely simple apparatus, by means of cross currents of steam. Ibe peculiarity of this contrivance is, that an ascending body of air, on entering this chest, divides itself spontaneously into any required number of thin horizontal films, by which a very extending surface is exposed to corresponding steam-heated metal surfacea Instead, therefore, of passing the steam through a series of pipes, along Which, but in an opposite direction, the condensed water has to return, it is conveyed at once from the boiler into the chest, or condenser, which, in fact, it is,) where, on having parted with its heat to the air as above described, it is condensed, and returned directly to the boiler. The chest or condenser, in the apparatus at the Bank of England, 18 but 3 feet square, yet the body of air to be heated, while passing over but 3 lineal feet, spreads itself oner no less than 164 superficial feet, and, coming in contact with a corresponding superficies, heated by the steam, it necessarily receives a very large sup- ply of heat in a short space of time. J & r- " The apparatus in the Bank of England, independently of heating and ventilating several large apartments, is put to the severest test, namely, that of evaporatinir the moisture from a series of 400 large mill-boards, with a surface of 1600 feet, and which moisture they have absorbed from the fresh printed bank notes which are dailv dried by this process. •' "With respect to the quantity of heat which this small apparatus is capable of im- parting to the air, this is accurately tested by the quantity of water which is con- aensed, and which amounts hourly to twelve gallons. "Of the efficacy of an artificial current produced by means of a fan or cylinder, Dr. Ure observes, that 'it has been ascertained that a power equivalent to one horse, in a steam engine, will drive at the rate of 80 feet per second a fan, the effective surfaces of whose vanes, and whose inhaling conduits, have each an area of 18 inches square, equal to that of a large steam boiler chimney. The velocity of air in the chimney, produced by a consumption of fuel equivalent to the power of twenty horses was no more than 86 feet per second; while that of the fan, as impelled by the power of one horse, was 66 feet per second. Hence it appears that the economy of ventilation by the fan is to that by the chimney draught, as 66 X 20 is to 35, or 88 to 1. It is obvious, therefore, that, with one bushel of coals consumed in working a steam-impelled eccentric fan, we can obtain as great a degree of ventilation, or we can displace as great a volume of air, as we could with 38 bushels of coals consumed in creating a chimney draught Econo- ™?' u T^^"^^^ *"*^ compactness of construction, are not^ however, the sole advantages which the mechanical system of ventilation possesses over the physical. It is infallible, even under such vicissitudes of wind and weather as would essentially obstruct any chimney draught ventilation, because it discharges the air with a momentum quite eddy proof; and it may be increased, diminished, or stopped altogether, in the twink- ling ot an eye, by the mere shifting of a band from one pulley to another. No state of atmospher*} without, no humidity of air within, can resist its power. It will impel the air of a crowded room, loaded with the vesicular vapors of perspiration, with equal certainty as the driest and most expansive." After so clear and practical an exposition of the advantages of a current^ mechani- caLy created, nothing further need be said of natural currents arising from mere in- crease of temperature, excepting that, by the adoption of the pump instead of the fan, a very considerable power is saved, and the operation performed much more effectively. Another peculiarity of Mr. Oldham's apparatus here merits attention. The large volume of air heated and passed off to the required apartments is, previously to iU being received into the heating chest, filtered and purified, by being deprived of all that noxious floating matter with which the atmosphere, particularly that of London, IS at all times charged, and which, if heated and sent into the apartments with the air, would but increase that noxious character, and render it still more injurious to the res- piration of human beings. Not only, indeed, are these offensive impurities which are floating in the atmosphere effectually separated, but a power is given of charging it with aromatic or antiseptic matter, thus rendering it not only the medium of warmth and ventilation, but of purifying and healthful influences. VENUS, is the mythological name of copper. VERDIGRIS. 895 VERATRINE, is a vegetable alkali, of a poisonous nature, extracted from the seeds of the Veratrum sabadilla, the roots of the Veratrum album, or while hellebore, and of Colchicum autumnale, or meadow saffron, in which plants it exists combined chiefly with gallic acid. It is obtained in the form of a white powder. It has an acrid, burning taste, but without any bitterness; it has no smell; but when snuffed into the nostrils, it excites violent and dangerous sneezing. It melts at a heat of 122'^ F., and concretes, on cooling, into a transparent yellowish mass. It restores the blue color of reddened litmus paper. It is hardly soluble in water or ether, but abundantly in alcohol. It consists of— carbon 66-76, hydrogen 8*54, nitrogen 5*04, and oxygen 19-60. Its saline compounds have an acrid and burning taste. Veratrine resembles strychnine and brucine, in its effects upon living bodies, producing tetanus and death in a moderate dose; not- withstanding whicli, it has been prescribed by some of our poison doctors, especially mixed with hog's lard, in the form of frictions on the forehead, for nervous maladies; but seldom, I believe, with any good effects. VERDIGRIS. {Vert-de-gris, Ft.; Grunspariy Germ.) The copper used in this manufacture, is formed into round sheets, from 20 to 25 inches diameter by one Iwenty- foartli of an inch in thickness. Each sheet is then divided into oblontf squares, from 4 to 6 inches in length, by 3 broad ; and weighing about 4 ounces. They are separately beaten upon an anvil, to smooth their surfaces, to consolidate the metal, and to free it from scales. The refuse of the grapes, after the extraction of their juice, formerly thrown on to the dunghill, is now preserved for the purpose of making verdigris. It is put loosely into earthen vessels, which are usually 16 inches high, 14 in diameter at the widest part, and about 12 at the mouth. The vessels are then covered with lids, which are surrounded by straw mats. In this situation the materials soon become heated, and exhale an acid odor; the fermentation beginning at the bottom of the cask, and gradually rising till it actuate the whole mass. At the end of two or three days, the manufacturer removes the fermenting materials into other vessels, in order to check the process, lest putrefaction should ensue. The copper plates, if new, are now pre- pared, by rubbing them over with a linen cloth dipped in a solution of verdigris; and they are laid up alongside of one another to dry. If the plates are not subjected to this kind of preparation, they will become black, instead of green, by the first operation. When the plates are ready, and the materials in a fermenting state, one of them is put into the earthen vessel for 24 hours, in order to ascertain whether it be a proper period to proceed to the remaining part of the process. If, at the end of this period, the plate be covered with a uniform green layer, concealing the whole copper, everything is right; but if, on the contrary, liquid drops hang on the surface ©f the metal, the work- nen say the plates are sweating, and conclude that the heat of the fermented mass has been inadequate ; on which account another day is allowed to pass before makin? a simi- lar trial. When the materials are finally found to be ready, the strata are formed in the following manner. The plates are laid on a horizontal wooden gratin?, fixed in the middle of a vat, on whose bottom a pan full of burning charcoal is placed, which heats them to such a degree, that the women who manasfe this work are obliged to lay hold of them frequently with a cloth when they lift them out. Ther are in this state put into earthen vessels, in alternate strata with the fermented m'aterials, the uppermost and undermost layers being composed of the expressed grapes. The vessels are covered with their straw mats, and left at rest. From 30 to 40 pounds of copper are put into one vessel. At the end of 10, 12, 15, or 20 days the vessels are opened, to ascertain, by the materials having become white, if the operation be completed. Detached glossy crystals will be perceived on the surface of the plates ; in which case the grapes are thrown away, and the plates are placed upright in a corner of the verdisris cellar, one against the other, upon pieces of wood laid on the ground. At the end of two or three days they are moistened by dipping in a vessel of water, after which they are replaced m their former situation, where they remain seven or eight days, and are then subjected to momentary immersion, as before. This alternate moistening and exposure to air is performed six or eight times, at regular intervals of about a week. As these plates are sometimes dipped into damaged wine, the workmen term these immer- sions, otie wine, two winesy &c. By this treatment, the plates swell, become green, and covered with a stratum of verdigris, which is readily scraped off with a knife. At each operation every vessel yields from nve to six pounds of verdigris, in a fresh or humid state; which is sold to whole- sale dealers, who dry it for exportation. For this purpose, they knead the paste ia wooden troughs, and then transfer it to leathern bags, a foot and a half long, and ten inches in diameter. These bags are exposed to the sun and air till the verdigris has at- tained a sufficient degree of hardness. It loses about half its weight in this operation; and It IS said to be knife-proof, when this instrument, plunged through the leathern bag, cannot penetrate the loaf of verdigris. 896 VTERDITER. The manufacture of verdigris at Montpellier is altogether domestic. In most vnnt farm-houses there is a verdigris celJar; and its principal operations are conducted by the females of the family They consider the forming the strata, and scraping off the ver- digris^ the most troublesome part Chaptal says that this mode of nTakin^ verdigris would admit of some improvements: for example, the acetification requires a warmer temperature than what usually rises in the earthen vessels; and the plates, when set aside to generate the coat of verdigris, require a different degree of heat and moisture from that re(juisite for the other operations. Verdigris is a mixture of the crystallized acetate of copper and the sub-acetate in varying proportions. According to Vauqnelin's researches, there are three compounds of oxide of copper and acetic acid ; 1, a subacetate, insoluble in water, but decomposinj? in that fluid, at common temperatures changing into peroxide and acetate; 2, a neutral acetate the solution of which is not altered at common temperatures, but is decomposed uy ebullition, becoming peroxide and superacetate; and, 3, superacetate, which in solution IS not decomposed, either at common temperatures or at the boilm.? point j and which caanot be obtained in crystals, except by slow spontaneous evaporation, in air or m vacuo The iiri>i salt, in the dry slate, contains 66-ol of oxyde; the second, 44-44 j Mr. Phillips has given the following analyses of French and English verdierii: Mnals 0/ Philosophy, No. 21.— ^ ^ French Veidigris. English Venligrifc Acetic acid - 29-3 29*62 Peroxyde of copper 4o'd 44'2o Water - - 25-2 25-51 Impurity - - 20 62 100-0 10000 Distilled verdigris, as it was long erroneously called, is merely a binaceiate or supei». acetate of copper, made by dissolving, in a copper kettle, one part of verdigris in two of distilled vinegar ; aiding the mutual action by slis;ht heat and agitation with a wooden spatula. When the liquor has taken its utmost depth of color, it is allowed to settle, and the clear portion is decanted off into well-glazed earthen vessels. Fresh vinegar is poured on the residuum, and if its color does not become deep enough, more verdigris is added. The clear and saturated solution is then slowly evaporated, in a vessef kept uniformly filled, till it acquires the consistence of sirup, and shows a pellicle on its sur- face ,- when it is transferred into glazed earthen pans, called oulas in the country. In eachof these dishes, two or three sticks are placed, about a foot Ions, cleft till within two inches of their upper end, and having the base of the cleft kept asunder by a bit of wood. This kind of pyramid is suspended by its summit in the liquid. AH these vessels are transported into crystallizing rooms, moderately heated with a stove, and left in the same state for 15 days, taking care to maintain a uniform temperature. Thus are ob- tained very fine groups of crystals of acetate of copper, clustered round the wooden rods; on which they are dried, taken off; and sent into the market. They are distinctly rhom^ boidal in form, and of a lively deep blue color. Each cluster of crystals weighs from five to six pounds ; and, in general, their total weight is equal to about one third of the verdigris employed. The crystallized binacetate of commerce consists, by my analysis, of— acetic acid, 62 ; oxyde of copper, 39-6 ; water, 8-4, in 100. I have prepared crystals which contain no water. There is a triple acetate off copper and lime, which resembles distilled verdigris in color. It was manufactured pretty extensively in Scotland some years aso, and fetched a high price, till I published an analysis of it in the Edinburgh Philosophical Journal. It IS much inferior, for all uses in the arts, to the proper binacetate. VERDITER, 01 BLUE VERDITER. This is a precipitate of oxyde of copper with lime, made by adding that earth, in its purest state, to the solution of nitrate of copper, obtained in quantities by the refiners, in parting gold and silver from copper by nitric acid. The cupreous precipitate must be triturated with lime, after it is nearly dry, to bring out the fine velvety blue color. The process is delicate, and readily misgives in unskilful hands. The ceTidres bleues en pate of the French, though analogous, arc in some respects a dif- ferent preparation. To make it, dissolve sulphate of copper in hot water, in such pro- portions that the liquid may have a density of 1-3. Take 240 pound measures of this so- lution, and divide it equally into 4 open-headed casks; add to each of these 45 pound measures of a boiling-hot solution of muriate of lime, of specific gravity, 1-317, whereby a double decomposition will ensue ; with the formation of muriate of copper and sulphate of lime, which precipitates. It is of consequence to work the materials well together at the moment of mixture, to prevent the precipitate agglomerating in unequal masses. VERDITER. 897 Lch preciSn soZ nf ?h "^K^ '""^nV' '""^'^^^ ^^ ^''^'' ^houl/ eithe'r caiaS Meanwhile, a magna of lime is to be prepared as follows-— Ifift nmin^- «<• • i furnish from 5»0 to 540 pounds rflrecn pas'e^ """''''""' "'^ """"'""' P"^"'"""" ■"»'«• deferLTi^erbfd'rjtilSo"" 2^"^^,"' J!!^,''"'"'"'^ ' •'^'"^'^- The cork mus Tow te Jmer an^elTfrfri ' ^' '^P?'^^'^^^ ^mid is run off; when it is fiUed up aLrwith provided it has not been lonJandlarlfnnv 7- h "a '''*^ '"v"' '™'' " '* «»*"» «ff««'«i. and gives it a bro,vn or blackishireefS ^ """'^ "'" """'"'^ '' »'" "^ '"^''«^ Calsel Euraci"iS''t '°-5- '^ "^ '^'"«'*' '"« P"'"^^ «f fabrication in Bretne.. dr;;a^/tt«tr^''te^;;Jefn'n;i'itr^s";T;r;'^.n 6. 225 lbs. of plates of old copper are^u by scUs^rs nto bi'ts o^T^T"' ""^'tk ward, washed -ulf ptr^-;;.?^^ sK:d%1„Tvre"I^S S "'^'^ "^ ■^^'- eo^mTn^sa'lfand'bKtr^fp^reJSy ISf !"%"='? and those who are to slir (/), must be placed alongside of each. The first set transfer the schlam rapidly into the latter back ; where the second set mix and agitate it all the time requisite to convert the mass into a consistent stale, and then leave it at rest from 36 to 48 hours. The whole mass is to be now washed ; with which view it is to be stirred about with the affusion of water, allowed to settle, and the supernatant liquor is drawn otf. This process is to be repeated till no more traces of potash remain among the blue. The deposiie must be then thrown upon a filter, where it is to be kept moist, and exposed freely to the air. The pigment is now squeezed in the filler-bags, cut into bits, and dried m the atmosphere, or at a temperature not exceeding 78° Fahr. It is only after the most coniplfte desiccation that the color acquires its greatest lustre. VERMICELLI, is a paste of wheat flour, drawn out and dried in slender cylinders, more or less tortuous, like worms, whence the Italian name. The gruau of the French is wheat coarsely ground, so as to free it from the husk ; the hardest and whitest part, being separated by sifting, is preferred for making the finest bread. When this gruau is a little more ground, and the dust separated from it by the bolting-machine, the granular substance called semoule is obtained, which is the basis of the best pastes. The softest and purest water is said to be necessaiy for making the most plastic ver- micelli dough ; 12 pounds of it being usually added to 50 pounds of semoule. It is better to add more semoule to the water, than water to the semoule, in the act of kneading. The water should be hot, and the dough briskly worked while still warm. The Italians pile one piece of this dough upon another, and then tread it well with their feet for two or three minutes. They afterwards work it for two hours with a powerful rolling-pin, a bar of wood from 10 to 12 feet long, larger at the one end than the other, having a sharp cutting edge at the extremity, attached to the large kneading- trough. When the dough is properly prepared, it is reduced to thin ribands, cylinders, or tubes, to form vermicelli and macaroni of different kinds. This operation is performed by means of a powerful press. This is vertical, and the iron plate or follower carried by the end of the screw fits exactly into a cast-iron cylinder, called the hell, like a sausage- machine, of which the bottom is perforated with small holes, of the shape and size in- tended for Ihe vermicelli. The hell being filled, and warmed with a charcoal fire to thin the dough into a paste, this is forced slowly through the holes, and is immediately cooled and dried by a fanner as it protrudes. When the threads or fillets have acquired the length of a foot, they are grasped by the hand, broken off, and twisted, while still flexi- ble, into any desired shape upon a piece of paper. The macaroni requires to be made of a less compact dough than the vermicelli. The former is forced through the perforated bottom, usually in fillets, which are afterwards formed into tubes by joining their edges together before they have had lime to become dry. The lazagms are macaroni left in the fillet or riband shape. Vermicelli is made with most advantage from the flour of southern countries, which IB richest in gluten. It may also be made from our ordinary flour, provided an addition of gluten be made to the flour paste. Vermicelli prepared from ordinary flour is apt VERMILLION. 899 \.. \ to melt into a paste when boiled in soups. It may, however, be weU made economicaUy by the following prescription :— ' Vermicelli or Naples flour - - - 21 Iba White potato flour - - . Boiling water. - - . - 14 — - 12 — Total 47 lbs. Affording 45 lbs. of dough, and 30 of dry vermicelli With gluten, made from common Hour, the proportions are : — Flour as before Fresh gluten - Water - 80 lbs. - 10 — - 7 — Total 41 lbs. Affording 30 lbs. of dry vermicelli or macaroni. r.f y^^^^^^^l^^ ?** 6'mna6ar, is a compound of mercury and sulphur in the proportion of 100 parts of the former to 1 6 of the latter, which occurs in nature as a common ore of quicKsiiver, and is prepared by the chemist as a pigment, under the name of VermiUon It is, properly speakmg, a bisulphuret of mercury. This artificial compound being ex- tensively employed on account of the beauty of its color, in painting, for making red sealing-wax, and other purposes, is the object of an important manufacture. When ver- miUon is prepared by means of sublimation, it concretes in masses of considerable thickness, concave on one side, convex on the other, of a needle-form texture; brown- jsh-red m the lump, but when reduced to powder, of a lively red color. On exposure to a moderate heat, it evaporates without leaving a residuum, if it be not contaminated flame *" *' * ^^""^^ ^' *^^* ^''^' *''*^ ^""""^ enUrely away, with a blue Holland long kept a monopoly of the manufacture of vermilion, from being alone in possession of the art of giving it a fine flame color. Meanwhile the French chemists examined this product with great care, under an idea that the failure of other nations to rival the Dutch arose from ignorance of its true composition ; some, with BertholleU imagined that it contained a little hydrogen ; and others, with Fourcroy, believed that the mercury contained in it was oxydized ; but, eventually, Seguin proved that both of these opinions were erroneous; having ascertained, on the Jne hand, that no hydro- fenous matter was given out in the decomposition of cinnabar, and on the other that sulphur and mercury, by combining, were transformed into the red sulphuret in close vessels without the access of any oxygen whatever. It was likewise supposed that the solution of the problem might be found in the difference of compositiorbetween v:L 1* ^ , /"'f!'"J'^''''^"^/''"''>'5 *"^ many conjectures were made with this view, the whole of which were refuted by Seguin. He demonstrated, in fact, that a mere change of temperature was sufficient to convert the one sulphuret into the other, withou occasioning any variation in the proportion of the two elements. Cinnabar r„rn I k"^ '" *-^'^l' '"^?^' convertible into elhiops, which in its turn ischan^ ilil h«Mh' ^^/''^''"''f !^' '""^l '^ ^ ^''^^'' temperature; and thence he was led to l7 elude that the difference between these two sulphurets was owing principally to the state of Sat Znr ''" "V^" ^«"^lit«ents. It would seem to result,'from all these research^ hat cinnabar is only an intimate compound of pure sulphur and mercury, in the pron^ tn^fp'^fi"^ '"' by analysis; and it is therefore reasonable to conclude, that in^X; to make fine vermilion, it should be sufficient to effect the union of its element^, at i high enough temperature, and to exclude the influence of all foreign matTCs buj notwithstanding these discoveries, the art of making good vermilion ?s near'lv i^ much a mystery as ever. M. Seguin, indeed, announced in his Memoks, tha" he ha^ succeeded m obtaming, m his laboratory, as good a cinnabar as that of HoUand and muchThTanfhn'' ""''V '^"JL^^*"^^-^^^ truth may be in this assertion, or however much the author may have been excited by the love of honor and profit, no manu- evt"To"foreta'Z\rnfr''r' 7 "'^^?^ his auspices. France is stilf as tributary i ever to foreign nations for this chemical product. At an exoosition some vears LrT indeed, a sample of good French vermilion was brought fXaTto pTove that tlie problem was nearly solved ; but that it is not so completely, may be inf^r?Id from the silence on this subject in M. Dupin's report of the last exposhion in ISsT w 1^^^ we .Tow "Sptr?' '"'^^ '^"""'^ "'^^ eulogiums anrSlsVthe jud^^^^^^^^^ of'r;iing.wai^ "''' '" "''^ '""'' ^^'^'y P"^^^ ^y '^^ ^'^»<^^ manufacturer CA^ J^nl'^v' XTT^ ""^ ^^ ^"^'? '°"'"*' published, long ago, in the ^rmales de Vhimie, vol. IV., the best account we yet have of the manufacture of vermilion in HoUand j 900 VERMILLION. one which has been since verified by M. Payss^, who saw the process practised on th« great scale with success. " The establishment in which 1 saw, several times, the fabrication of sublimed sul- phuret of mercury," says M. Tuckert, " was that of Mr. Brand, at Amsterdam, beyond the gate of Utrecht ; it is one of the most considerable in Holland, producing annually, from three furnaces, by means of four workmen, 48,000 pounds of cinnabar, besides other mercurial preparations* The following process is pursued here : — "The ethiops is first prepared by mixing together 150 pounds of sulphur, with 1080 pounds of pure mercury, and exposing this mixture to a moderate heat in a flat polished iron pot, one foot deep, and two feet and a half in diameter. It never takes fire, pro- vided the workman understands his business. The black sulphuret, thus prepared, is ground, to facilitate the filling with it of small earthen bottles capable of holding about 24 ounces of water ; from 30 to 40 of which bottles are filled beforehand, to be ready when wanted. " Three great subliming pots or vessels, made of very pure clay and sand, have been previously coated over with a proper lute, and allowed to dry slowly. These pots are set upon three furnaces bound with iron hoops, and they are covered with a kind of iron dome. The furnaces are constructed so that the flame may freely circulate and play upon the pots, over two thirds of their height. *' The subliming vessels having been set in their places, a moderate fire is kindled in the evening, which is gradually augmented till the pots become red. A bottle of the black sulphuret is then poured into the first in the series, next into the second and third, in succession; but eventually, two, three, or even more, bottles may be emptied in at once; this circumstance depends on the stronger or weaker combustion of the sulphuret of mercury thus projected. After its introduction, the flame rises 4 and sometimes 6 feet high ; when it has diminished a little, the vessels are covered with a plate of iron, a foot square, and an inch and a half thick, made to fit perfectly close. In this manner, the whole materials which have been prepared are introduced, in the course of 34 hours, into the three pots ; being for each pot 360 pounds of mercury, and 50 of sulphur ; in all, 410 pounds." The degree of firing is judged of, from time to time, by lifting oflf the cover ; for if the flame rise several feet above the mouth of the pot, the heat is too great ; if it be hardly visible, the heat is too low. The proper criterion being a vigorous flame play- ing a few inches above the vessel. In the last of the 36 hours* process, the mass should be dexterously stirred up every 15 or 20 minutes, to quicken the sublimation. The subliming pots are then allowed to cool, and broken to pieces in order to collect all the Termilion incrusted within them ; and which usually amounts to 400 lbs., being a loss of only 60 on each vessel. The lumps are to be ground along with water between honzonta. stones, elutriated, passed through sieves, and dried. It is said that the rich tone of the Chinese vermilion may be imitated by adding to the materials for subliming one per cent, of sulphuret of antimony, and by digesting the ground article first in a solution of sulphuret of potassa, and, finally, in diluted muriatic acid. The humid process of Kirchoft* has of late years been so much improved, as to furnish a vermilion quite equal in brilliancy to the Chinese. The following process has been recommended. Mercury is triturated for several hours with sulphur, in the cold, till a perfect ethiops is formed ; potash ley is then added, and the trituration is continued for some time. The mixture is now heated in iron vessels, Aviih constant stirring at first, but afterwards only from time to time. The temperature must be kept up as steadily as possible at 130° Fahr., adding fresh supplies of water as it eva- porates. When the mixture which was black, becomes, at the end of some hours, brown-red, the greatest caution is requisite, to prevent the temperature from being raised above 1 14°, and to preserve the mixture quite liquid, while the compound of sulphur and mercury should always be pulverulent. The color becomes red, and brightens in its hue, often with surprising rapidity. When the tint is nearly fine, the process should be continued at a gentler heat, during some hours. Finally, the vermilion is to be elutri- ated, in order to separate any particles of running mercury. The three ingredients should be very pure. The proportion of product varies with that of the constituents, as we see from the following results of experiments, in which 300 parts of mercury were always ero ployed, and from 400 to 450 of water : — Sulphur. Potash. Vermilion obtained. 114 76 330 115 75 331 120 120 321 150 152 382 120 180 245 100 180 244 60 180 142 I— ^ VINEGAR. 901 The first proportions are therefore the most advantageous; the lasf^ which are those of M. Kirchofi^ himself, are not so good. r ^'^^^'^ ^^^^^ ^^*' ^^ P**"^ of quicksilver, 114 of sulphur, 75 of caustic potassa, and from 400 to 4o0 of water, form very suitable proportions for the moist process : that the best temperature was 113° F.; and that 122° was the highest limit of heat compatible With the production of a fine color. The theory of this process is by no means clear. We may suppose that a sulphuret of potassium and mercury is first formed, which is eventually destroyed, in proportion as the oxygen of the air acts upon the sulphuret of potassium itself. There may also be p duced some hyposulphite of mercury, which, under the same influence, would be tr formed into sulphuret of mercury and sulphate of potash. Sulphuret of potassium and mercury furnish also vermilion, but it is notbeaui».^ Red oxyde of mercury, calomel, turbith mineral, and the soluble mercury of Hahnemann, treated with the sulphuret of potassium, or the hydrosulphuret of ammonia, are all capa- ble of giving birth to vermilion by the humid way. The vermilion of commerce is often adulterated with red lead, brickdust, dragon's blood, and realgar. The first two, not being volatile, remain when the vermilion is heated to its subliming point ; the third gives a red tincture to alcohol ; the fourth exhales its peculiar garlic smell with heat; and when calcined in a crucible with carbon- ate of soda, and nitre in excess, aflfords arsenic acid, which may be detected by the usual cliemical tests. VINEGAR The gross revenue derived from vinegar manufactured in England in the year 1845, amounted to 284,817/. yielding a nett revenue of 67,182/. The eross revenue from vinegar manufactured in the United Kingdom, in the same year, amounted to 311,61 1/., producing a nett revenue of 62,936/. Vinegar; to detect sulphuric acid in.— Add a few drops of a concentrated solution of chloride of calcium (muriate of lime) to the vinegar in question, not the least turbid- ness will ensue, even at a boiling heat But if free sulphuric acid be present in the vinegar, a very considerable turbidness will appear, followed by a precipitate of sulphate of lime. If the proportion of the sulphuric acid in the vinegar is larger than J part, the precipitate will appear even before it has become perfectly cold. ^^^^ ^ In addition to the article Acetic Acid, I avail myself of this opportunity of describ- ing the recent invention of Anhydrous Acetic acid as made by Mr Gerhardt It is obtained by mixing perfectly dry fused acetate of potash with about half its weight of chloride of benzoyle and applying a gentle heat; when a liquid distils over, which, after being rectified, has a constant boiling point of 279^ F., is heavier than water with which it does not mix until after it has been agitated with it for some time. It dis- solves at once in hot water, forming acetic acid. Chlorbenzoyle,. is prepared by transmitting dry chlore gas through pure oil of bitter almonds, till this at a boiling heat affords no more hydrochloric acid. The chlor- benzoyle is a limpid colorless fluid of 11 96 specific gravity. It has a peculiar very penetrating smell, drawing tears from the eyes, as horseradish does. It has a hieh boiling pointy and burns with a smoky flame. It dissolves sulphur and phosphorus with the aid of heat, and combines with sulphuret of carbon in all proportions Vinegar; new Method for manufacturing pure.— The decomposition of acetate of lime or lead by means of sulphuric acid has many inconveniences, and there is danger of the product being contaminated with sulphuric acid. Christl* was therefore induced to employ hydrochloric acid as a decomposing agent, and has found that when this acid 18 not used m excess, the distillate contains scarcely an appreciable trace of chlorine. A mixture of 100 lb& of raw acetate of lime, obtained from the distiUation of wood and containing 90 per cent of neutral acetate, with 120 lbs. of hydrochloric acid (20° Baum6) IS allowed to stand during a night, and then distilled in a copper vessel. The application of heat requires to be gradual, in order to prevent the somewhat thick liquor from running over. The product of acetic acid amounted to 100 lbs. of 8° Baum6- it had a faint yellow color and empyreumatic odor, which may be perfectly removed by ti-eatment with wood-charcoal and subsequent rectification. ir j j In order to obtain the acetate of lime sufficiently pure, Volckelf adopts the following process :---The raw pyrolignous acid is saturated with lime without previous distil- lation. A part of the resinous substances dissolved in the acid are thus separated in combination with lime. The solution of impure acetate of lime is either allowed to stand until it becomes clear or filtered, t then evaporated in an iron pan to about one half, and hydrochloric acid added until a drop of the cooled liquid distinctly reddens htmus-paper. The addition of acid serves to separate great part of the resin still held * Dingler's Polytech. Joum. t Ann. der Chem, und Pharm. i A part ifi distilled off in a copper etill in order to obtain wood-epirit 902 VINEGAR. in solution, which collects together in the boiling liquid, and may be skimmed off, and likewise decomposes the compounds of lime with creosote, and some other imperfectly- known volatile substances, which are driven off by further evaporation. As these vol- atile substances have little or no action upon litmus-paper, it being reddened by the liquor is a sign that not only are the lime compounds of these substances decomposed, but also a small quantity of acetate of lime. The quantity of acid necessary for this purpose varies, and depends upon the nature of the pyrolignous acid, which is again dependent upon the quantity of water in the wood from which it is obtained. 160 litres of wood-liquor require from 4 to 6 lbs. of hydrochloric acid. Tlie solution of acetate of lime is evaporated to dryness, and a tolerably strong heat applied at last, in order to remove all volatile substances. Both operations may be performed in the same iron pans; but when the quantity of salt is large, the latter may be more advantageously effected upon cast-iron plates. The drying of the salt requires very great care, for the empyreumatic substances adhere very strongly to the acetate of lime, as well as to the compound of resin and acetic acid mixed with it, and when not perfectly separated, pass over with the acetic acid in the subsequent distillation with an acid, commimicating to it a disagreeable odor. The drying must therefore be continued until upon cooling the acetate does not smell at all, or but very slightly. Ik then has a dirty brown color. The acetic acid is obtained by distillation with hydro- chloric acid in a still with a copper head and leaden condenser ; when proper precau- tions are taken, the acetic acid does not contain a trace of either metal. The quan- tity of hydrochloric acid required cannot be exactly stated, because the acetate of lime 18 mixed with resin, and already formed chloride of calcium. In most instances 90 or 95 parts by weight of acid, 1-16 spec, grav., are sufficient to decompose completely 100 parts of the salt, without introducing much hydrochloric acid into the distillate. The distilled acetic acid possesses only a very faint empyreumatic odor, very different from that of the raw pyrolignous acid ; it is perfectly colorless, and should only become slightly turbid on the addition of nitrate of silver. If the acid has a yellowish color, this is owing to resin having been spirted over in the distillation. It is therefore ad- visable to remove the resin, which is separated on the addition of hydrochloric acid, and floats upon the surface of the liquid, either by skimming or filtration through a linen cloth. The distilled acid has a specific gravity ranging between 1058 and 1-061, containing upwards of 40 per cent of anhydrous acetic acid. It is rarely that acid of this strength is required ; and as the distillation is easier when the mixture is less con- centrated, water may be added before or towards the end of the distillation. Volckel recommends as convenient proportions — 100 parts of acetate of lime, 90 to 95 hydrochloric acid, 25 parts of water, which yield from 95 to 100 parts of acetic acid of M05 spec. grav. ; 150 litres of raw pyrolignous acid yield about 60 lbs. of acetic acid of the above specific gravity. The acid prepared in this way may be still further purified by adding a small quan- tity of carbonate of soda and redistilling; it is thus rendered quite free from chlorine, and any remaining trace of color is likewise removed. The slight empyreumatic smell may be removed by distilling the acid with about 2 or 3 per cent of acid of chromate of potash. Oxide of manganese is less efficacious as a purifying agent Although pure acetic acid may be procured by the distillation of vinegar, the whole of the acid cannot be obtained except by distilling to dryness, by which means the ex- tractive substances are burnt, and the distillate rendered impure. In order to obviate this difficulty. Stein* proposes to add 30 lbs. of salt to every 100 lbs. of vinegar; the boiling-pomt is thus raised, and the acid passes over completely. By the quick process of Ham, when the fermentation is finished, the greatest care ought to be taken that all access of air is excluded from the wash, and that its tempe- rature be reduced to, and maintained at a heat below the point where acetification com- mences. Those who, like Messrs. Evans, Hill, & Co., of Worcester, attach great im- portance to the fabrication of the best keeping vinegars, are in the habit of filtering the fermented wash, and also of stowing it away for many months in a cool situation ere It 18 passed through the acetifier: and there cannot be a moment's doubt concerning the great value of this practice, not only as regards the appearance and flavor of the resulting vinegar, but also in respect to its dietetic and sanitary properties. All recently fermented wash contains a quantity of partially decomposed gluten, some of which is mechanically suspended merely, but by far the larger portion exists m a state of solution through the agency of carbonic acid gas. * Polytech. Centralblatt, 1852, p. 395. V^ /. VINEGAR. 903 A filter will remove the former, but time alone can dissipate the carbonic acid and lead to the deposition of the latter. At all events, time is the only available remedy, for though heat would expel the carbonic acid, yet it would at the same time drive oflF the alcohol; and agitation in contact with air, though it removed the carbonic acid, would tend to the formation of acetic acid, by which the gluten would be kept in solu- tion more decidedly than before, and thus lead to the production of a turbid, ropy and impure vinegar, extremely liable to decompose and undergo the putrefactive fermenta- tion. It is obvious therefore that the theoretical conditions needed in the treatment of fermented wort by the vinegar-maker are precisely those which we have shown to be in use at Worcester. That is to say, the gluten, when insoluble, should be removed by a filter, and when held in solution by carbonic acid, this must be slowly expelled by keeping at a temperature too low for acetification to take place, and which may be as- sumed at less than 55^^ Fahr. Fermented wort stowed away at this temperature for six months will flow to the acetifier perfectly limpid and bright; it will cause no de- position of gluten upon the birch twigs, and thus secure complete oxidation; it will rapidly take on the grateful flavor of acetic ether, and never beeome tainted by the formation of that nauseous and noxious product aldehyde, which so frequently con- taminates ill-made vinegar. Presuming, however, that all the necessary precautions, with respect to care in wash- ing, fermenting, and keeping the wort, have been attended to, we may now pass on to the acetifier, that is to say Ham's acetifier. This is a wooden vat or vessel (see sketch) about 12 feet in height, and from Y to 8 1488 DM § mSM yijij I e m oiei«f«f« tu'.WI , , 1 'IJi/ I^hT M m L / feet in diameter, closed at top and bottom, except at the openings for the introduction of the wash and the exit of the vinegar. The sides are perforated by a few small holes for the admission of air, and within are three floors or partitions perforated with nu- merous holes for the passage of the wash through them. Upon these floors are laid bundles of birch twigs, to favor the dispersion and division of the fluid which passes through the acetifier, and is thus brought into the most intimate contact with the oxy- gen contained in the vessel, or admitted through the openings in its sides. The fluid or wash is of course admitted at the top of the acetifier, and suffered to trickle slowly through the masses of birch twigs and through the partitions, thus causing a rapid ab- sorption of oxygen, and consequent production of vinegar, which with any undecora- posed wash flows out at the bottom of the vessel, and is again pumped up to the top, and so on until the process is finished. If we examine the circumstances connected with the formation of vinegar in this way, we shall perceive at once, that it is a case of par- tial combustion, or, in other words, an example in which an organic compound is oxi- dized at a temperature and under conditions which prevent complete oxidation. Every one must have observed that when common coals are thrown upon afire, a part immediately bursts into flame, from which copious particles of soot or carbon are thrown off unburnt, though of the other constituent of the coal, that is to say, the hydrogen gat 904 VINEGAR. no particle escapes unoxidized. This arises from the fact that, except at very high temperatures, hydrogen has a greater affinity for oxygen than carbon has; consequent- ly, as the supply of oxygen from the atmospheric air in the immediate neighborhood is limited, the hydrogen seizes upon its equivalent to the exclusion of the carbon which, therefore remains and constitutes soot Exactly in the same way the hydrogen of the alcohol in the wash oxidizes to the exclusion of the carbon, and vinegar is formed from the remaining or carbonaceous element, which becomes itself slightly oxidized. Thus 2 atoms of alcohol are composed of: — Carbon - - - . . Hydrogen - - - - . Oxygen - - - . . whilst acetic acid or pure radical vinegar contains of — Carbon Hydrogen Oxygen atoms. - 4 - 6 • 2 atoms. - 4 - 3 - 3 I^ therefore, we suppose the contact of air with alcohol to have led to the absorption of oxygen, so as to have oxidized three atoms of hydrogen, and thus produced three atoms of water, we have left Carbon ----.. Hydrogen ----.. Oxygen ----.. which, by the mere absorption of another atom of oxygen, becomes Carbon Hydrogen - Oxygen atoms. - 4 • 8 - 8 atoms. - 4 - 8 - 8 or pure acetic acid, with which the water produced from the hydrogen remains in union and forms vinegar. From the above it follows, that as the oxidization of hydrogen generates heat or caloric, there ought to be a very appreciable rise in temperature during the passage of the wort through the acetifier. And, in practice, this is found to be the case; so that precautions are needed to prevent the heat from rising so high as to vaporise the remaining alcohol of the wash. The temperature sought to be obtained 18 about 90° or 92° Fahr., at which oxidation goes on freely, and the loss of alcohol is moderate. In using the word moderate, we speak practically rather than chemically for m reality the loss is very serious with strong worta From practical results, con- ducted with more than ordinary care, we have ascertained that about one-third of all the extractive matter of the malt and grain is lost or dissipated during the processes of fermentation and acetificatiou. Thus, a wort having a specific gravity of 1072 or in technical language, weighing about 26 lbs. per barrel, afforded a vinegar containing'5-4 per cent of pure acetic acid, and a residuary extract of 10 lbs. from 36 gallons. The former of these would indicate 35 lbs. of sugar, or 13-7 lbs. per barrel of gravity whilst the latter shows 3-8 lbs. per barrel; the two united being only 17-6 lbs. instead of 26, the original weight The loss, therefore, has been 8-6 lbs., or from a specific gravity of 1072 to less than 1-050. The prodigious destruction of extract seems to im- ply that great improvements may yet take place in the manufacture of vinegar. The manufacture of vinegar, by Ham's process, is an extremely interesting operation, and when conducted with proper care furnishes results of the most satisfactory and uniform character. These, however, are not to be obtained without a vast amount of e^erience and the most vigilant attention on the part of the manufacturer. Thus a difference in the water, in the maU, in the mode of washing, in the cooling of the wort or in the fermentation of the wort, will each give rise to modifications in the acetifying process which no subsequent skill or labor can afterwards rectify. There seems no doubt that the most important points in Ham's method are the cooling and fermentation of the wort, though, where perfection is sought for, no one of the other conditions can be omitted or neglected with impunity. We shall, therefore, proceed to treat of these conditions seriatim, rather than m the order of their importance. At first sight it might be supposed that the purer the water the better, that is to say, the less the amount of -*=i «_.- L VIOLET BYE. 905 earthy or saline constituents the more valuable the water would be for making vinegar. Experience, however, teaches us the contrary, and science confirms the truth of this teaching, by pointing out the real nature of the operation. When pure water is made to act at a high temperature upon the ordinary ingredients of a vinegar-maker's mash tun, it is not alone the sugar, gum, and starch of the grain which enters into solution, for under such circumstances the gluten is also dissolved. But this gluten is composed of vegetable albumen and vegetable gelatine, the former of which, as is well known, is capable of being decomposed and precipitated by many earthy and metallic salts, of which the sulphate of lime is one. If, therefore, this salt exists in the water employed for the fabrication of vinegar or of ale or beer, the wort will contain little or no vegeta- ble albumen; consequently, the vinegar or beer made with such water never becomes cloudy or roapy, as happens when pure water is used, for these defects arise from an excess of albuminous matter. The water used for making the celebrated Burton ale contains a great deal of sulphate of lime, and the spring water of Worcester, which is employed by the extensive firm of Hill, Evans and Co., in that city, vinegar-makers, contains also a very large amount of sulphate of lime, and no doubt contributes much toward maintaining the well-established reputation of that firm. Whenever, therefore, much sulphate of lime exists in water, without the presence of any noxious ingredient, such water may always be relied upon as favorable for the production of good beer and vinegar. As regards the malt, or rather the mixture of malt and grain, employed for the pro- duction of wort, the common Scotch distiller's formula is the best, containing, as it always does> a considerable per-centage of oats, for the long husk of the oat greatly facilitates the operation of draining, and thus secures the thorough separation of the wort from tie spent grains. In practice it is found necessary to ferment only two gravities, a high and a low, all the other qualities of vinegar being made by mixing or diluting these after acetificatiou. The most common, and unquestionably the best gravity for fermentation is that which in technieal language weighs about 20 lbs,, or has a specific gravity of 1*056 ; the other, or that intended for strong or proof vinegar, being of spec. grav. l.o72 ; this latter affords a vinegar containing about 5^ per cent of anhydrous acetic acid. In every instance the fermentation must be carried to its utmost limit or to zero at least, and in cooling the wort prior to fermentation, great care must be used to prevent the accession of the acetous fermentation before the yeast is added ; for if this happens to any considerable extent the nitrogenized matter of the yeast is then permanently retained in solution by the acetic acid, and this may give rise to the inconvenience called the " mother." To secure a perfect vinegar by Ham's process, as much attention is required, during the cooling and fermentation, as for the finest ale, and this axiom cannot be too strongly inculcated into the minds of vinegar-makers. The heat of the fermenting tun should not exceed 75° Fahr., as the alcohol formed by the process is apt at higher temperatures to pass off in considerable quantity with the carbonic acid, and thus give rise to a loss of vinegar. Presuming that the fermentation has been well conducted, and that the specific gravity of the wash is as low as water, or 1*000, the next step is to pass it through that apparatus which constitutes the great peculiarity of Ham's process. This apparatus is ciilled tiie acetifier. See Acetic Acid. VIOLET DYE, is produced by a mixture of red and blue coloiin?-matters, which are applied in succession. Silk is dyed a fugitive violet with either archil or Brazil wood ; but a fine fast violet, first by a crimson with cochineal, without tartar or tin mordant, and after wasliinar, it is dipped in the indigo vat. A finish is sometimes given with archil. A violet is also given to silk, by passing it through a solution of verdigris, then through a bath of logwood, and, lastly, through alum water. A more beautiful violet may be communicated by passing the alumed silk through a bath of Brazil wood, and after wash- ing it in the river, through a bath of archil. To produce violets on printed calicoes, a dilute acetate of iron is the mordant, and the dye is madder. The mordanted goods should be well dunged. A good process for dyein? cottons violet, is— first, to gall, with 18 or 20 pounds of nut- galls for every 100 |>ounds of cotton ; second, to pass the stuff, still hot, through a mordant composed of— alum, 10 pounds; iron-liquor, at 1^° B., and sulpnate of copper, each 5 or 6 pounds ; water, from 24 to 28 gallons; working it well, with alternate steeping, squeez- ing, airing, dipping, squeezing, and washing; third, to madder, with its own weight of the root ; and fourth, to brighten with soap. If soda be used at the end, instead of soap, the color called prune de monsieur will be produced ; and by varying the doses of the in gredients, a variety of violet tints may be given. The best violets are produced by dyeing yarn or cloth which has been prepared with oil as for the Turkey-red process. See Madder. For the violet pruneau a little nitrate of iron is mixed with the alum mordant, which 906 VITRIFIABLE PIGMENTS. VITRIFIABLE PIGMENTS. 907 !ii; makes a black; but this is changed into violet pnmeau, by a madder-bath, followed by a brightening with soap. VITRIFIABLE COLORS ; see Enamels, Pastes, Pottery, and Stained Glass. VITRIFIABLE PIGMENTS. The art of painting with vitrifiable pigments has not kept pace with the progress of science, and is far from having attained that degree of perfection of which it is capable. It still presents too many difficulties to prove a fertile field to the artist for his labors : and its products have, for this reason, never held that rank in art which is due to them from the indestructibility and brilliancy of the colors. The reason of this is attributable to the circumstance that the production of good vitrifiable pigments is mere chance work; and notwithstanding the numerous f)apers published on this subject, is still the secret of the few. The directions given ia arger works and periodicals are very incomplete and indefinite ; and even in the other- wise highly valuable Traite des Arts Ceramiques of Brongniart, the chapter on the preparation of colors is far from satisfactory, and is certainly no frank communication of the experience gathered in the royal manufactory of Sevres. Now it is equally important to art and science that as many persons as possible should contribute to develop this art: but so long as every individual about to engage in the subject finds himself compelled, as I was on commencing, to discover the knowledge al- ready acquired by others, but kept secret, the cost of time and trouble requisite is suf- ficient to frighten most persons, and, what is of greatest injury to the art, especially the scientific chemist, from working on the subject The branch of painting with vitrifiable pigments which has acquired its greatest de- velopment is the art of painting on porcelain. The glaze of hard felspar porcelain, owing to its difficult fusion, produces less alteration upon the tone of a color of the easily fusible pigments than is the case in painting upon glass, enamel, fayence, Ac. The colors for painting upon porcelain are all of them, after the firing, colored lead- glasses throughout ; but before this operation, most of them are mere mixtures of col- orless lead-glass, the^wx, and a pigment. In the so-called gold colors, purple, violet, and piuk, the pigments are preparations of gold, the productions of which has hitherto been considered as especially difficult and uncertain. The following are the processes which I employ : — Light Purple. — 5 grammes of tin turnings are dissolved in boiling nitromuriatic acid, the solution concentrated in the water bath until it solidifies on cooling. The per- chloride of tin prepared in this manner, and which still contains a slight excess of mu- riatic acid, is dissolved in a little distilled water, and mixed with two grammes of so- lution of protochloride of tin of 1*700 sp. gr., obtained by boiling tin turnings in excess with muriatic acid to the required degree of concentration. Tliis mixed solution of tin is poured into a glass vessel, and gradually mixed with 10 litres of distilled water. It must still contain just so much acid that no turbidness results from the separation of oxide of tin ; this may be ascertained previously by taking a drop of the concentrated solution of tin upon a glass rod, and mixing it in a watch glass with distilled water. A clear solution of 0'5 grammes gold in nitromuriatic acid, which must be as neutral as possible, is poured into the solution of tin diluted with 10 litres of water, constantly agitating the whole time. The gold solution should have been previously evaporated nearly to dryness in the water bath, then diluted with water, and filtered in the dark. On adding the gold solution, the whole liquid acquires a deep red color, without, however, any precipitate being formed ; this instantly separates upon the addition of 60 grammes of solution of ammonia. But if no precipitate should result, which may happen if the amount of ammonia was too great in proportion to the acid contained in the liquid, and in which case the liquid forms a deep red solution, the precipitate im- mediately results upon the addition of a few drops of concentrated sulphuric acid. It subsides very quickly. The supernatant liquid should be poured off from it as soon as possible, and replaced 5 or 6 times successively by an equal quantity of fresh spring water. When the precipitate has been thus sufficiently washed, it is collected upon a filter; and as soon as the water has drained off completely, removed while still moist with a silver spatula, and mixed intimately upon a ground plate of glass by means of a spatula and grinder with 20 grammes of lead-glass, previously ground very fine upon the same plate with water. The lead-glass is obtained by fusing together 2 parts of minium with 1 part of quartz sand, and 1 part of calcined borax. The intimate mixture of gold-purple and lead-glass is slowly dried upon the same glass plate upon which it had been mixed in a moderately warm room, carefully pro- tected from dust, and when dry, rubbed to a fine powder, and mixed with three grammes of carbonate of silver. In this manner we obtain 33 grammes of light purple pigments from 0"6 gramme gold. The above proportion of lead-glass and carbonate of silver to the gold precipitate holds good only for a certain temperature, at which the color must be burnt-in npon the por- celain, and which is situated very near the fusing point of silver. To obtain the color with a less degree of heat, the amount of lead-glass added to the gold must be greater, but that of the carbonate of silver lesa The same holds good with respect to the preparation of the purple pigment for glass painting. The best purple may be spoiled in the baking in the muffle. When this is done at too low a temperature, the color remains brown and dull ; but if the right degree of temperature has been exceeded, it appears pale and bluish. Reducing, and especially acid, vapors, vapors of oxide of bismuth, » dipping is eompleted, T sh^'e^Uy" to K^t^V „ r^'^^"^^^^ ^ ^'"" '"'* '"' each fibre of the fleece willXSfhe oiol.Cof t Jir Pf'^''/''^^ P"'"™'* will be keptdrv the an^»l E..lT„ . i^ r^ . urP'"',''S -"ater, and thus the wool factnring purples! ^ ""' eomfortable, and the wool improved for manu- emX"l"a.t;i:':'rplZLost''r,°' t' "' t'^ s*''"--' """^ '-v ^ in conjunction with tKrorr«lif''"n '"! "P,!"'"« 'T'*"' ■""? ''« '"P'-'W The at4e invention is patented f„7he„amtn?^l/J'".''*''>- °' T'^''' »<«**«• l»51.-Neu,lm; Journal, ^lui ° Alexander Me.n. and enrolled Jun«i sitK^e rt"lt'tratJ^M±t"^al^^^^^^^ '^^T ^ .^T" Analyses. The symbol N iUnnfl. k'\ ^®^®^^ °[ ^^ermany, according to the best OQ O 3 H S ^ Eh El ^ a m O ^ 4!Ji) i DQ s r »4 s JS „ s < ^^ 1 1 i ; 1 jg e 6 6 ;5« s 9 ia § 2 § 1^3 W'u dm m CO 0] I s s 3 S ! 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Mineral waters may, m most cases, be artificially prepared, by the skilful application of the knowledge derived from analysis, with such precision as to imitate yery closely the native springs. When the various earthy or metallic constituents are held in solu- tion by carbonic acid, or sulphuretted hydrogen, they should be placed along with their due proportions of water, in the receiver of the aerating machine (see Soda WatebI and then the proper quantity of gas should be injected into the water. Sufficient agi- tation will be given by the action of the forcing pump to promote their solution P^a^r^Yi^ u'j 'TJ^^Z''''^ S'"*''^ ^ ^^'^^ ofTenhury, Worcestershire, the Froperty of 8. Holmes Godson, Esq. By methods somewhat similar to those described in my paper on the "Analysis of the Moira Brine Spring." which the Royal Society honored with a place in their Transactions for 1834, part ii., I obtained the foUowing results from one gallon— Y0,0'>0 water-grain measuresLl gallon :— 1. Chlorsodium (muriate of soda) 2. Chlorcalcium (muriate of lime) - 3. Chlormagnesium (muriate of magnesia) 4. Sulphate of lime - . ^ . ' 6. Protocarbonate of iron 6. Bromide of sodium (bromsodium) graini. 1801-4 425-6 61-3 6-0 1-6 16-2 Total saline contents— .1802-0 Specific gravity of the water at 60° F.—1-0208 Taste, bitter saline, but not unpleasantly so. ..f^'" ^t^^fu^u ^^^"^ ^"""^ P"'^^*^ ^""^ '^'^ medicinal virtues as a deobstruent In reference to the bromine constituent, it is doubly richer than the Moira spring water, -olln ^^^.^^^^^^J'^'n of the presence and approximate proportion of bromine in such a saline water is attended with no difficulty. Having concentrated a considerable quan- «lZ.f ir ^7 ev*P<>ration to so such a pitch as to separate the greater part of the readily crystallizable muriate of soda, add to the filtered mother-water a small portion of pretty strong chlorine- water. The bright golden yellow color immediately produced indicates in^ th.TnHr'' ' •"1!""^??/''^"?.*^ «^'^ ^^ hydrobromic acid. Ether being poured into the bottle partially filled with the saline solution, and agitated therewith seizes il nf .T'°^' *°i "*? v^P"*'* "'*'* ^^^^ ^*^ «°^ ^««^ i'l a rich crimson solution on the ivLi ^^;j,^««?^«red hquor. Care must be taken that chlorine has not been used in tho!S. ^^^^""^^'^ ^^^ ""T^ Pr«<^^«« wo»W be vitiated, which consist, first, in decanting of nof/Jh?r *'7P<>"'1<3'?«<^ saturating it with pure potash lye, so^as to form bromidi •IS wifh ^; • T^'« «*>l"t»r ^^^°^ evaporated, and gently ignited, is to be supersatur- «^wl hi i ^K^*^i ^^""TT precipitated with nitratS of silver, and the brown r^Z^T^tl T K^'^'- filtered, dried, and gently ignited. 100 parts of that bromide IS f K ^ of bromine In Mr. Godson's mineral spring, there are very nearly 12* from the warr'""^ ^''* ^ ' ""^ "^ *^'''^^'"' "^^^^^ eitracUng on the large^cia! ra^t.^^?^'"'-!!^'''^ ^^^ ^^^"^ stripped of its bromine by potash lye, may be nearly all Tfehlnr^^Jm ♦r°P'^P'''T/^r'^'^ ^' **^ ^^ repeatedfy applied to fresh quantities t.t^if ? rnother-water. If the bromide of potaLium be mixed with one-tliird of its Sio .2Tf'?7^^rt.^^??''' ^°^ *^" ™^'^^"'-« ^i«ti"«^ ^ith its own weight of sul- ?i.;l' fl"^' 1'^-''^."^ ""'^^ ^^^i'^ "^^'S^^ ^^ ^ater, from a retort whose beak dips into a maX ent?rl" ."^'"5''';' i^J ^^"T^^^ ^^''^ ««™^« ^^^^ f«"« ^o the bottom, and hme) ^ de-hydrated by re-distillation over-chlorcalcium (calcined muriate of .hwffiflJiT'ri! °^*y »1«<> be extracted, and that very economically, by distilling the Thpfrol^^ IT-T^'' ^^ *^' 'P""S ^^^^ ^^' mixture of manganese an^d oil of vftrbL Id thThv I ^^ passes over may be afterwards purified by washing with water, and then by the process above described, with potash, nitric acid Ac -Dr Ureii, PharmaceuticalJournal, 1848, vol. viii. Na 4. Nanheim a spa recently discovered'on the south-eastern declivity of Johannisbenr tTlr r ^ST Frankfort-on-the-Mayne by railway, displays^ the phenomen^ l^h ofrbnni^'riiit^' °' '±T^''t^' * ^^1"™° ^^ white Lm Lb^bling ur2 "r 3 feet! with carbonic acid gas, 670 feet above the level of the sea. It is an Artesian well- murilte of «od/Jr'^° gravity of 1-007 at 72-50 Fahr. Ite chief constituentrare rtrb:omid:':h:fur' """^^ ^^ p^^^^^' ^^--^ -^ ^-^^ ^^« ^-^ ^^^-^-t. wifh^linL?I'''f ^°°^^^^'"& ^'i J.6 «^ 256 grains of sea salt, 8} of muriate of magnesia, b^fh !nP f of magnesia and lime in considerable quantity, and of spec, gravel -01? L fn thri'Jr/.'r .^?^.,^^«^r' -^ "' Oeynhausen, Sear Miiden upon^he We er I 18 in the immediate vicinity of an immense brine spring which throws up 64 cubic feet mm WAX. 929 of salt water containing 416 grains in 10.000 of saline matter at a temperature of 96° Fahr. This spring contains also some bromine, and throws out jets of carbonic acid gas. This well has the prodigious depth of 1994 feet below the level of the sea ; and its mouth is 217 feet above it* Here there have been 67 baths of different classes established. The whole has been well investigated and placed under the superintendence of Dr. Bischofl^ Professor of Chemistry in Bonn. WAX (Cire, Fr. ; Wachs, Germ.), is the substance which forms the cells of bees. It was long supposed to be derived from the pollen of plants, swallowed by these insects, and merely voided under this new form ; but it has been proved by the experi- ments, first of Mr. Hunter, and more especially of M. Huber, to be the peculiar secretion of a certain organ, which forms a part of the small sacs, situated on the sides of the median line of the abdomen of the bee. On raising the lower segments of the abdomen, these sacs may be observed, as also scales or spangles of wax, arranged in pairs upon each segment. There are none, however, under the rings of the males and the queen. Each individual has only eight wax sacs, or pouches; for the first and the last ring are not provided with them. M. Huber satisfied himself by precise experi- ments that bees, though fed with honey, or sugar alone, produced nevertheless a very considerable quantity of wax ; thus proving that they were not mere collectors of this substance from the vegetable kingdom. The pollen of plants serves for the nourishment of the larvae. But wax exists also as a vegetable product, and may, in this point of view, be regarded as a concrete fixed oil. It forms a part of the green fecula of many plants, particularly of the cabbage ; it may be extracted from the pollen of most flowers ; as also from the skins of plums, and many stone fruits. It constitutes a varnish upon the upper surface of the leaves of many trees, and it has been observed in the juice of the cow-tree. The berries of the Mxjrica angustifoliay latifoliay as well as the ceriferay afford abundance of wax. Bees* wax, as obtained by washing and melting the comb, is yellow. It has a peculiar smell, resembling honey, and derived from it, for the cells in which no honey has been de- posited, yield a scentless white wax. Wax is freed from its impurities, and bleached, by melting it with hot water or steam, in a tinned copper or wooden vessel, letting it settle, running oflf the clear supernatant oily-looking liquid into an oblong trough with a line of holes in its bottom, so as to distribute it upon horizontal wooden cylinders^ made to revolve half immersed in cold water, and then exposing the thin ribands of films thus obtained to the blanching action of air, light, and moisture. For this pur- pose, the ribands are laid upon long webs of canvass stretched horizontally between standards, two feet above the surface of a sheltered field, having a free exposure to the sunbeams. H6re they are frequently turned over, then covered by nets to prevent their being blown away by winds, and watered from time to time, like linen upon the grass field in the oU method of bleaching. Whenever the color of the wax seems station- ary, it is collected, remelted, and thrown again into ribands upon the wet cylinder, in order to expose new surfaces to the blanching operation. By several repetitions of these processes, if the weather proves favorable, the wax eventually loses its yellow tint entirely, and becomes fit for forming white candles. If it be finished under rain, it will become gray on keeping, and also lose in weight. In France, where the purification of wax isaconsiderableobjectof manufacture, about four ounces of cream of tartar, or alum, are added to the water in the first melting- copper, and the solution is incorporated with the wax by diligent manipulation. The whole is left at rest for some time, and then the supernatant wax is run ofi" into a settling cistern, whence it is discharged by a stopcock or tap, over the wooden cylinder revolving at the surface of a large water-cistern, kept cool by passing a stream con- tinually through it. The bleached wax is finally melted, strained through silk sieves, and then run into circular cavities in a moistened table, to be cast or moulded into thin disc pieces, weigh- ing from two to three ounces each, and three or four inches in diameter. Neither chlorine, nor even the chlorides of lime and alkalis, can be employed with any advantage to bleach wax, because they render it brittle, and impair its burning quality. Wax purified, as above, is white and translucent in thin segments ; it has neither taste nor smell ; it has a specific gravity of from 0-960 to 0-966 ; it does not liquefy till it be heated to 154|° F. ; but it softens at 86°, becoming so plastic, that it may be moulded by the hand into any form. At 32P it is hard and brittle. It is not a simple substance, but consists of two species of wax, which may be easily separated by boiling alcohol. The resulting solution deposites, on cooling, the waxy body called cerine. The undissolved wax, being once and again treated with boiling alcohol, finally affords from 70 to 90 per cent. V its weight of cerine. The insoluble residuum is the myricine of Dr. John, so called because it exists in a much larger pro- -■■^■T"Mj'.#lk-^Ft-.--jO>.-^s^^., ,_^ I 930 WEAVING. I ^s,tl%:x^^i^r'tnTt,'L a"s,s»"i ''^f ' '*»» "«"' ""-s of .h. undergoes. &e th«e two anicl« ' """^ ""''™' """'-Position, which cerin« .inrwVi'ch d^Sr .rer^r! a^nilVrAw' K S '^•"'"'h •"• »" «' '"'>«"- with mutton suet This fr«nH mo,, i r ^aji" substance ; and more frequently .hereby .tfcd, it Ju^wfTete^d XTc^ whSi^'l'^ir^ Ir '" ^"'^^ ""' " WAV '\u vi'LT^'^^'""'- «>'-• f™"foretin!3«r'-' *"'"'"'''' '^' '""'■ ""'"• texture, . conchoidal (r^ciu^Xy>tT.mt' l^TTZtV'' T"' "^ ' !■""." "* a mortar. Its specific gravity varierS'u'snnl' «2« S^' T ^ P"'«"«^'l«^l^e'!'T:^::^uTci:S^^^^^^^^^ ^ will furnish the qHantity required foV tl^^e Ln j^h ^ .V "' ""J""! therefore be taken as sixth of that number of bobbins is usuall mounL I '"'•'"^t'^ P''*^^ ^^ *=^«'^- ^ne loosely in a horizontal dTectJon u^t^^rrs^^^^^^^^ ""'' 5^^? ««' that they may revolve, and give off the yarn fr^elv Th^^ ' '" •Z'^"*'^ ^'*°'^' ^*» and causes the reel b Jo revo^ by tur:iir?o::rdtith\l^ ^aXhe ^Jef 'c,^^f itl't'h'e' endless rope or band d. The bobbins filled with yarn are placed in the frame e. There is a sliding piece at f, called the heck box, which rises and falls by the coiling and uncoil- ing of the cord g, round the central shaft of the reel H. By this simple contri* Vance, the band of warp- yarns is wound spirally, from top to bottom, upon the reel, i, i, i, are wood- en pins which separate the different bands. Most warping mills are of a prismatic form ; having twelve, eighteen, or more sides. The reel is com- monly about six feet in m height, so as to serve for measurin*' Pxartlr ,in«« •» <^?a™eter, and seven feet the warp. All the threadrfrmn f^f / ^ ^^. **^ periphery the total length of of a series of lely.roHshe^^ ^^^^^f the heck r, which consists • part of each, to receive and S'eoTe thread The'hT'iJ ' T"^} ^''' ^' '^^ "PP" either of which may be lifted by a small handlp hL km ^'^u^-^ ^"'° ^^^ P^'^^' alternately. Hence; when one of them t raised a mtr«v'' *^-' P'' f" P^*^^^ the two bands of the warp • but when^h! nfl ■ \^ vacuity is formed between this way, the lease is Troduced aT each end of the warn 'and'-r-'"''^ ^' 'Tl''"^' ^"^ ri:^:ShiSe.s: x^^iS^V^??^^^^ and from left to right, tiU^ ^^2^ J^ Zfj^^^S:^^ ^ WEAVING, BY HAND. 931 breadth that is wanted ; the warper's principal care being to tie immediately every thread as it breaks, otherwise deficiencies would be occasioned in the chain, injurious to the ap- pearance of the web, or productive of much annoyance to the weaver. The simplest and probably the most ancient of looms, now to be seen in action, i« that of the Hindoo tanty, shown in Jig. 1494. It consists of two bamboo rollers; one for the warp, and another for the woven cloth ; with a pair of heddles, for parting the warp, to permit the weft to be drawn across between its upper and under threads. The shuttle is a slender rod, like a large net- ting needle, rather longer than the web is broad, and is made use of as a batten or lay, to strike home or tondense each successive thread of weft, against the closed fabric. The Hindoo carries this simple im- plement, with his water pitcher, rice pot, and hooka, to the foot of any tree which can afford him a comfortable shade ; he there digs a large hole, to receive his legs, along with the treddles or lower part of the harness ; he next extends his warp, by fastening his two bamboo rollers, at a proper distance from each other, with pins, into the sward ; he attaches the heddles to a convenient branch of the tree overhead ; inserts his great toes into two loops under the gear, to serve him for treddles ; lastly, he sheds the warp, draws through the weft, and beats it close up to the web with his rodshullle or batten. . • . j r i The European loom is represented in its plainest state, as it has existed for several centuries, in fig. 1495. a is the warp-beam, round which the chain has been wound ; b represents the flat rods, usually three in number, which pass across between its threads, to preserve the lease, or the plane of decussation for the weft ; c shows the heddles or healds, consisting of twines looped in the middle, through which loops the warp yarns are drawn one half through the front heddle, and the other through the back one ; by 1495 moving which, the decussation is readily effected. The yarns then pass through the dents of the beed under d, which is set in a moveable swing-frame e, called the lathe, lay, and also batten, because it beats home the weft to the web. The lay is freely suspended to a cross-bar f, attached by rulers, called the swords, to the top of the lateral standards of the loom, so as to oscillate upon it. The weaver, sitting on the bench g, presses down one of the tred- dles at H, with one of his feet, whereby he raises the corresponding heddle, but sinks the alternate one ; thus sheds the warp, by lifting and depressing each alternate thread, through a little space, and opens a pathway or race-course for the shuttle to traverse the middle of the warp, upon its two friction rollers m, m. For this purpose, he lays hold of the picking-peg in his right hand, and, with a smart jerk of his wrist, drives the fly-shuttle swiftly from one side of the loom to the other, between the shed warp yarns. The shoot of weft being thereby left behind from the shuttle pirn or cop, the weaver brings home, by pulling, the lay with its reed towards him by his left hand, with such force as the closeness of the texture requires. The web, as thus woven, is wound up by turning round the cloth beam i, furnished with a ratchet-wheel, which takes into a holding tooth. The plan of throwing the shuttle by the picking-peg and cord, is a great improvement upon the old way of throwing it by hand. It was contrived exactly a century ago, by John Kay, of Bury in Lancashire, but then resident in Colchester, and was called the fly-shuttle, from its speed, as it enabled the weaver to make double the quantity of narrow cloth, and much more hroadcloth, in the same time. The cloth is kept distended, during the operation of weaving, by means of two piecet 932 WEAVING, BY POWER. The gr ater part of plain weaving, and much even of the figured, is now performed b. ^^^° 1496 WEAVING, BY POWER. 933 the power loom, caUed mifier mScanique d tisser, in Frencli F,v ^aq^ cast-iron power loom of Sharp and Roberts a a' «?: I^l 1496, repreBenls the standards, on the front of the loom, d, is thi ^rel't «;r? nf %*^'* side uprights, or two sides together. ., is the front cross-te^i^lt T^^rorl^teTilZt ends are bolted to the opposite standards a, a', so as to bind the framework most firmly together, g', ig the breast beam, of wood, nearly square ; its upper surface is sloped a little towards the front, and its edge rounded ofl^", for the web to slide smoothly over it, in its progress to the cloth beam. The beam is supported at its end upon brackets, and is secured by the bolts g', g'. H, is the cloth beam, a wooden cylinder, mounted with iron gudgeons at its ends, that on the right hand being prolonged to carry the toothed winding wheel h'. fc', is a pinion in gear with h'. h", is a ratchet wheel, mounted upon the same shaft h"', as the pinion h'. h', is the click of the ratchet wheel h". A'", is a long bolt fixed to the frame, serving as a shaft to the ratchet wheel h", and the pinion h'. i, is the front heddle-leaf, and i', the back one. J, J, j', j', jacks or pulleys and straps, for raising and depressing the leaves of the heddles. 3'\ is the iron shsdl which carries the jacks or system of pulleys j, j, j', j'. k, a strong wooden ruler, con- necting the front heddle with its treddle. l, l', the front and rear marches or treddle- pieces, for depressing the heddle leaves alternately, by the intervention of the rods fe, (and k\ hid behind k). m, m, are the two swords (swing bars) of the lay or batten, n, is the upper cross-bar of the lay, made of wood, and supported upon the squares of the levers n,'w', to which it is firmly bolted, n', is the lay-cap, which is placed higher or lower, according to the breadth of the reed; it is the part of the lay which the hand- loom weaver seizes with his hand, in order to swing it towards him. n' is the reed contained between the bar n, and the lay-cap n'. o, o, are two rods of iron, perfectly round and straight, mounted near the ends of the batten-bar n, which serve as guides to the drivers or peckers o, o, which impel the shuttle. These are made of bufl'alo hide, and should slide freely on their guide-rods, o', o', are the fronts of the shuttle-boxes ; they have a slight inclination backwards, p, is the back of them. See figs, 1497 and 1498. o", o", are iron plates, forming the bottoms of the shuttle-boxes, p, small pegs or pins, planted in the posterior faces p (fig. 1498) of the boxes, round which the levers p' turn. These levers are sunk in the substance of the faces p, turn round pegs p, being pressed from without inwards, by the springs p'. p'',fig. 1496, (to the right of k,) is the whip or lever, (and q", its centre of motion, corresponding to the right arm and elbow of the weaver,) which serves to throw the shuttle, by means of the pecking-cord p"y attached at its other end to the drivers o, o. On the axis of q", a kind of eccentric or heart wheel is mounted, to whose concave part, the middle of the double band or strap r, being attached, receives impulsion ; its two ends are attached to the heads of the bolts r', which carry the stirrups r", that may be adjusted at any suitable height, by set screws. s (see the left-hand side of^g. 1496) is the moving shaft, of wrought iron, resting on the two ends of the frame, s' (see the right-hand side) is a toothed wheel, mounted ex- teriorly to the frame, upon the end of the shaft s. s" (near s') are two equal elbows, in the same direction, and in the same plane, as the shaft s, opposite to the swords m, m, of the lay. z, is the loose, and z', the fast pulley, or riggers, which receive motion from the steam- shaft of the factory, z", a small fly-wheel, to regulate the movements of the main shaft of the loom. T, is the shaft of the eccentric tappets, cams, or wipers, which press the treddle levers alternately up and down ; on its right end is mounted t', a toothed wheel in gear with the wheel s', of one haif its diameter, t", is a cleft clamping collar, which serves to sup- port the shaft t. u, is a lever, which turns round the bolt w, as well as the click h'\ u', is the click of traction, for turning round the cloth beam, jointed to the upper extremity of the lever u ; its tooth tt', catches in the teeth of the ratchet wheel h". tt", is a long slender rod, fixed to one of the swords of the lay m, serving to push the lower end of the lever u, when the lay retires towards the heddle leaves. X, is a wrought-iron shaft, extending from the one shuttle-box to the other, supported at its ends by the bearings x, x. Y, is a bearing, affixed exteriorly to the frame, against which the spring bar z, rests, near its top, but is fixed to the frame at its bottom. The spring falls into a notch in the bar Y, and is thereby held at a distance from the upright a, as long as the band is upon the loose pulley z' ; but when the spring bar is disengaged, it falls towards a, and carries the band upon the fast pulley z, so as to put the loom in gear with the steam-shaft of the factory. Weaving, by this powerful machine, consists of four operations : 1. to shed the warp" by means of the heddle leaves, actuated by the tappet wheels upon the axis q', the rods fe, fe', the cross-bar e, and the eyes of the heddle leaves i, i' ; 2. to throw the shuttle (see fig, 1495), by means of the whip lever p", the driver cord jt>, and the pecker o; 3. to drive home the weft by the batten n, n'; 4. to unwind the chain from the warp beam, and io draw it progressively forwards, and wind the finished web upon the cloth beam H, by the click and toothed wheel mechanism at the right-hand side of the frame. For i ! i 934 WELD. rh,;**L r ° *^t ^'^^^lonary, I shaU give here a short notice of the best kind^ •hutUe for weaving hair. Fig. 1499,shows in plan A, and in longitudinal sectioaB,, or mouth, wheaee i^e^t^i:^'°I^^lt'':^'':SlLi ''■'^' '°^«"t" "« «""«« «V i"' mouth, and removing L ThLb lets ?L L^r K "^i' k"* ^/ ^^'' "^°*^> ^"*° ^^^ rollers, x, x. are likp thn«P nf flir „k„+*i v 7 ^ weaver s leii nana. Ihelriction sbuttle c'an'n'ot be^l™r ' w'4 ftoS'sWe' ZZ'" Th?!'"? -"venience, a, .he shuttle opens at the same time iL tr>,f if 3 . ■ ^ '"""' "'"'='» receives the 5^»tt-d.t^o-ES£S^ S^^^w ^i?^z^ - » S^ ?=^ a^ir-ii^i^dij^ifS^^ They are the'drp Sb'eL end. remain, when one or more are drawn on/ h^^ Indian rubber, so that the others flat where the Indian rrbersDr?n^ exert. L.r/'- ^K ^°^\°^ ^^^ ^'^^^^s are F. The spring is formed by S^ o^ft 1 i^^^^ f' '^T^ ^^ ^he dotted line at of a caoutehoSe bouiror flask falniLtK^^^^ ^'^T ^cT ^^^ ^"•'^ature of the neck the groove of the shmt?e whLbv the "th- **'"'? ^'"^''1^ ^?' ^'"'^ ^"^ * ^^'^ ^'^P^^ ^" Ihe inlaid hairs, w" e s^les liL /^^^^^^ ^^°"^ ^^'^ y^^ld, presses upon two places of the groove Tgutter to nreUt t^P ^^^^^^ ^? ^'' P^''"-^ ^^^^^^^^ ^^^«»gh of the s)-;ttle, which is s"Srchar^.T;hh t^^^^^^^^ '^""-"'"^ "J ^'^ ^^^ midle across th. Vened warn with thp nnp Ln^ '■• u .^ workman shoves the tool of hairs b> e pro^^ctfnrends and hnlH^r'"'? T'^ ^}? °^^'' ^^^ requisite number more through the Xr^The r'emLni hi «Tr ^^'l' ^^'J^^ K^'^"^' '^^ «^"ttle once and only those for the single dec^sat^^^^^^^^ I'' *^' ^'^^"^^ ^^ ^^' «P"»^«' on either side. A weaver with th?s ton? pT? '° ^^ ^^\,*° ^'^ ^^cured to the lis he could do with the mouth-Ihuttle "™ ^'^^ ^ **°""" ^""^th of cloth of what run^Kl^::.rti^^^ ^^ ^^^ — ^^ the yarns or threads whici ^^cuZ^^To^I/'^u^^^^^^ -"-1 J'-baceous plant, leaves dye yellow and aS^' the di p. of •*' ^"'^'^ '"'''''''• "^'^^ stems and the which period its dyeing power is ereateTt • /n/l oO t ^^"^*^ "^f^^P^^ ^^^n in seed, at the market. ^ ^ * ' ^''^ ^^^^'^ ^^ing simply dried, is brought into Chevreul has discovered a yellow coloring principle in weld, which he has called WELLS, ARTESIAN. 935 luteoline. It may be sublimed, and thus obtained in long needle-form, transparent, yellow crystals. Luteoline is but sparingly soluble in water; but it nevertheless dyes alumed silk and wool of a fine jonquil color. It is soluble in alcohol and ether; it com- bines with acids, and especially with bases. When weld is to be employed in the dye-bath, it should be boiled for three quarien of an hour; after which the exhausted plant is taken out, because it occupies too much room. The decoction is rapidly decomposed in the air, and ought therefore to be made only when it is wanted. It produces, with Solution of ising-glass Litmus paper Potash ley - Solution of alum - Protoxyde salts of tin Acetate of lead Salts of copper Sulphate of red oxyde of iron a slight turbidity. a faint reddening, a golden yellow tint, a faint yellow. a rich yellow ditto a dirty yellow-brown a brown, passing into olive. precipitation. A lack is made from decoction of weld with alum, precipitated by carbonate of saicja or potassa. See Yellow Dye. . WELDING (Souder, Fr. ; Sckweissen, Germ.), is the property which pieces of wrought iron possess, when heated to whiteness, of uniting intimately and permanently under the hammer, into one body, without any appearance of junction. The welding temperature is usually estimated at from 60° to 90° of AVedgewood. When a skilful blacksmith is about to perform the welding operation, he watches minutely the eflfect of the heat in his forge-fire upon the two iron bars; and if he perceives them beginning to burn, he pulls them out, rolls them in sand, which forms a glassy silicate of iron upon the surface, so as to prevent further oxydizement ; and then laying the one pro- perly upon the other, he incorporates them by his right-hand hammer, being assisted by another workman, who strikes the metal at the same lime with a heavy forge- hammer. Platinum is not susceptible of being welded, as many chemical authors have erroneous- ly asserted. Mr. T. H. Russell, of Handsworth, near Birmingham, obtained a patent, in May, 1836J for manufacturing welded iron tubes, by drawing or passing the skelp, or fillet of sheet iron, five feet long, between dies or holes, formed by a pair of grooved rollers, placed with their sides contiguous ; for which process, he does not previously turn up the skelp from end to end, but he does this so as to bring the edges together at the lime when the welding is performed. He draws the skelp through two or more pairs of the above pincers or dies, each of less dimension than the preceding. In making tubes of an inch of internal diameter, a skelp four inches and a half broad is employed. The twin rollers revolve on vertical axes, which may be made to approach each other to give j)ressure ; and they are kept cool by a stream of water, while the skelp, ignited to the welding heat, is passed between them. They are affixed at about a foot in front of the mouth of the furnace, on a draw-bench ; there being a suitable stop within a few inches of the rollers, against which the workman may place a pair of pincers, having a beU- mouthed hole or die, for welding and shaping the tube. In the first passage between the rollers, a circular revolving plate of iron is let down vertically between them, to prevent the edges of the skelp from overlapping, or even meeting. The welding is performed at the last passage. WELLS, ARTESIAN. See also Artesian Wells. The following account of a successful operation of this kind, lately performed at Mortlake, in Surrey, deserves to be recorded. The spot at which this undertaking was begun, is within 100 feet of the Thames. In the first instance, an auger, seven inches in diameter, was used in pene- trating 20 feet of superficial detritus, and 200 feet of London clay. An iron lube, 8 inches in diameter, was then driven into the opening, to dam out the land-sprinqs and the percolation from the river. A 4-inch auger was next introduced through the iron tube, and tlie boring was continued until, the London clay having been perforated to the depth of 240 feet, the sands of the plastic clay were reached, and water of the softest and purest nature was obtained ,- but the supply was not suflBcient, and it did not reach the surface. The work was proceeded with accordingly ; and after 55 feet of alternating beds of sand and clay had been penetrated, ihe chalk was touched upon. A second tube, 4| inches in diameter, was then driven into the chalk, to stop out the water of the plastic sands; and through this tube an auger, 3^ inches in diameter, was introduced, and worked down through 35 feet of hard chalk, aboundinj? with flints. To this succeeded a bed of soft chalk, into which the instrument suddenly penetrated to the depth of 15 feet. On the auger being withdrawn, water gradually rose to the surface, and overflowed. The expense of the work did not exceed 300/. The general summary of the strata pene- mmmr fl- 936 WHALEBONE. i!l : lamipa., consisting oUbreriaidlVag^^^^^^^^^ ^« 1^%-^' '' '"^^ ^^^^J thcfringes upon their edges, enable the anTmi^^n ^ii ^''f "^'^^^ ""^ ^he whale, which, by rows of teeth (which il wants) forbehveen ^r ' '""'"' '" ^^^ ^^^'^^ throigh detam the minute creatures upon Xh it S 'C^fiT"' i^^""?,^"^ ^^ *^^'^h and lateral cohesion, as they are nil transverse vd?p„/«^^^^^ ^^ whalebone have little detached .n the form of Ion? filamentrorXis.ies ^.ll?,^^*^ """^^ '^'''^''''' ^ ^'^^'^^7 are externally compact, smooth and ^.^L.!, li r ^ f>J<^»y or scythe-shaped plate/ ma parallel series, by ^hat is caS tTe^^^^'o^l^jr^ P^'jf^' ^hey are'conn'ec^; side of Its mouth, to the number of about ^M -f-h ^"/"^^'' ^^^ ^'^ arranged along each is usually found near the middle of TeleT.' i.Th ^""""'^ f '^^ '""^^^^ Wo^, which designate the size of the fish. tL greatest ieni.h S".'",^^?''''^ ^^ '^' ^'^^'^^^ to but It rarely exceeds 12 or 13 Th^t } u^^^. hitherto known has been 15 feet and the average thicknes: f'm fiS to%tV„\^ 7^^ en^,ls fron. 10 to 12 Inched; altogether in the mouth of the whale resemble 1 '1 '", T^' J^' ''''''> ^^^^^d They are cleansed and soAened befm-P nn?r ' u ^V^'^^ *^'""' ^he roof of a house, ewer. ^"^ ^^*^'e cutting, by boiling for two hours in a long Whalebone, as brought from Pro i j • pieces, comprising ten Ir twelve bTade."il' '' commonly divided into portable junks or separate blades, the gum ard'he ha^J^frL^'l' ^^'^ »« occasionally subdivided into daring the voyage. The pric^^ whLetTfl,^.^.» ? **^'" '!T"^ ^^ '^^ ^'^^o^ WHEEL CARRIAGES.. a carpenter's bench, and is then man, takin*' hold of th*. h^r^At ^ ' ^"^ ^^^^' Mn.. and .U. ..-. ..„ i:;;;^ ^^^^^f^^^^^^ rection of the fibres ; bein "careful to cut noL Lr Vk'" ^' ^° ''^^"^ ««" « ^^''^^ i" the di- arethen dried, and plinedle^elupo the "o^ J^'ese prismatic slips •n this operation, is used, instead of hair for sLffinr'^nf* ^^^^*>'-«"s matter detached From Its flexibili^, stren-th elasiirftv In/vu," mattresses. purposes : for ribs to'umbrdlas o ''j^ra Jol^^^^^^^^^ ^-P'^^ed for many hats, &c. When heated by steam, or a sand bath f LT^ ''^^'V ^^^ ^^^ f'^me-work of like horn, into various shapes, wSch it retainrj^T ; " 'f ^"> ^"^ ™ay be bent or moulded, Snuff-boxes, and knobs of wa^kir.sticL marbe^^^^^ ""'^"^ compression. In this way The surface is polished at first wifh grind' pumice stonT feh '''f '^ ^^^^^ '^ ''' ^'^^'• with dry quicklime, spontaneously slaked and S' ^"' °"^ '^^*^'' «»d finished increase their thickness, so as' Trender the mateZr''"i^ *?? ''/'^' ^^ ^'^^'^ ^ sticks, whip handles, parasol and umbrella stiTk-^r^i ^^/''^^\^ ^^'^^ir^g walking, accomplishes this by bending the stnl to'ether^ntroT •'^'' .r''"-"^ ^«^'«' *<^ H^ thereby softening them, and in that staTe coCre JnTth^^^^^ '"'^ ^ ^^^^"^ «»»e«t^ propriate^machinery ; for a description. ^^.'^.T^o^ZZ:, Sn'Vr.'j, ^ f ^ '^r u'™.' ^"^ ^"« ^^^ ^pace b, left afterwards replaced, keeps a f tVht /„ nmtit nn'?>,°^'^^ ^?^' ""^ ^'^^ ^^"^^» being put into the space betwixt tne collet- p s aC th^e l«rl ' ''^.:'^' *i""" «" «"«»»' '<> be moveable round the axletree ara,, and Vein. maSe /ast^to ,'h"^'^ k ?' """" ^> ^'' ^'^^S pins 5, ^, revolves along with the bush, actfn^aaain.rthVr^'n^-'' '"^^"^ °^ ^^^ ^wo keeps the wheel fast to the axletree, untH bv "reSnl n '""^'^ ?u^' ^' ^^ ^''^ «™> *"' I"" «" S" ">« win run a thousand miles without requTrinrfrlsTo ,1^.'^ '"""" '" ^ ""''» ""^ ^'^ "»«/ sX:wh':hti^s,TeU;'aitn HHr^^^^^^^^^^^ together by rivets through them The sna.i h'?'^^ /u^^ ^*'"'!^'' ^"'^ ^" ^'^-^^ are attached Should be filled up with^light Tv^od the Ure the7nu^"o^ '''?r" "T ^^^'"'"^ ^^^ ^^^^oet and glands clasping both felloes ^ ' '^"'^ fastened to the felloes by bolts .vp?ne :s;tt; rhr;'r;o7.'hXri^,-t" ^t' "^^"^ '''"^- " '^. « « pre^tettfni^'^Vla^re^K"^^^^^^^ in the boxes of the wheels Ssob^ectTseffeS'hv',!," "■"',"1'' ""''"" '^"'- ^hl.kin1 in certain parts of the box, and brfcontnt,^! • '^ ',''\'" V''^'''''™ '''" '^"h'' «>»»» so as to bear against the end of the axTeJee wUh',!* '"" '^""'1' "'"' '" ""'""i »p! that situation, without the possibility of turnin^lnd\r'5'if' "-^ 'f^""?' ""^ '^ "-^W i» loose. ' "' '■"""'•= found, or allowing the axletree to become Mff. 1608 shows the section of the hn^, «f » 1.1 • ■ . secured in it The general form of the box andTf tt T?" w, '"^ ^^ ^^' '^^^^tree axles, there being recesses in the box for th; reeenLn f '{ '' ^!' f '"^" ^' ^^^'' "^^^ a cap « is inserted, with a leather col laJ enclosed^n^? k/'!' ^^ ^^^ ^"^ «^ ^^e axle, axle; which cap, when screwed up sufficient vtthf t l m -^ *l^'^"?' *^« ^"<^ «^ ^he or screw passed through the cap a, into the e"^ of the '1^ '^ *^'^ '^^""^^^" ^^ « P^" end of the iron box being shown at/y. I609 '*''' * representation of thi« 1508 1609 Jn the can a, there is also a groove for conducting the oil to the interior of the box, wilk a screw at the opening, to prevent it running out as the wheel goes round. The particular claims of improvement are, the leather collar aarainst the end of the axle ; the pin going through one of the holes in the end of the box, to fix it ; and the channel for conducting the oil. Mr. Mason's patent, of August, 1830, applies also to the boxes and axles of that con- struction of carriage wheels which are fitted with the so called mail-boxes ; but part of the invention applies to other axles. Fig. 1510, represents the nave of a wheel, with the box for the axle within it, both shown in section longitudinally; fig. 1511, is a section of the axle, taken in the same direction ; andyig. 1512, represents the screw cap and oil-box, which attaches to the outer extremity of the axle-box. Supposing the parts were put together, that is, the axle inserted into the box, then the intention of the different parts Avill be perceived. The cylindrical recess a, in the box of the nave, is designed to fit the cylindrical part of the axle 6 ; and the conical part c, of the axle, to shoulder up against a corresponding conical cavity in the box, with a washer of leather lo prevent its shaking. A collar d, formed by a metallic ring, fits loosely upon a cylindrical part of the axle, and is kept there by a flange or rim, fixed behind the cone c. Several strong pins /,/, are cast into the back part of the box ; which pins, when the wheel is attached, pass through corresponding holes in the collar d ; and nuts being screwed on to the ends of the pins/, behind the collar, keep the wheef securely attached to the axle. The screw-cap g, is then inserted into the recess h, at the outer part of the box, its conical end and small tube i, passing into the recess fe, in the end of the axle. The parts being thus connected, the oil contained within the cap g, will flow through the small tube t, in its end, into the recess or cylindrical channel /, within the axle, and will thence pass through a small hole in the side of the axle, into the cylindrical recess a, of the box ; and then lodging in the groove and other cavities within the box, will lu- bricate the axle as the wheel goes round. There is also a small groove cut on the out- side of the axle, for conducting the oil, in order that it may be more equally dis- tributed over the surface and the bear- ings. This construction of the box and axle, as far as the lubrication goes, may be applied to the axles of w^heels in general ; but that part of the invention which is designed to give greater secu- rity in the attachment of the wheel to the carriage, applies particularly to mail axles. Mr. William Mason's patent in- vention for wheel carriages, of August, 1831, will be understood by reference to the annexed figures. Fig. 1513, is a plan showing the fore-axlelree bed a, a, of a four-wheeled carriage, to which the axletrees 6, 6, are jointed at each end ; fig. 1514 is an enlarged plan ; and fig. 1515 an elevation, or side view of one end of the said fore-axletree bed, having a Collinge's axletree jointed lo the axletree bed, by means of the cylindrical pin or bolt e, which passes through and turns in a cylindrical hole d, formed at the end of the axletree bed, shown also in the plan view,/5f. 1516, and section, /^r. 1517. The axletree 6, is firmly united with the upper end e, of the pin or bolt c ; and to the lower end of it, which is squared, the guide piece /, is also fitted, and secured by the screw ^r, and cap or nut h, seen \nfig. 1515, and in section in fig. 1518. There are leather washers i, i, let into recesses made to receive them in the parts a, b, and/, the intent of 1510 ■ HQ U22> WHEEL CARRIAGES. 1^8 1517 1616 1614 po8iteforeaxIetree?r iSlV^ -''^^ fore-axletree bed T In L7Zl \^i.°^^ ^' jser^w^ O.J " -*^^. T^^ ^^« gu'de piece f. tnrna n.^ fi similar mannef "^ Th. tV^'i ^^PP^^'^^ ^"^ «f the TXte^^ The^axletree may be incased in th. . . ' ' "' '''"^^ ^'^ Til WHEEL CARRIAGES. 941 small compass, by throwing the axles of all the four wheels simultaneously into different positions. They effect this object by mounting each wheel upon a separate jointed axle, and by connecting the free ends of the four axles by jointed rods or chains, wiih the pole and splinter- bar in front of the carriage. To fix the ends of the spokes of wheels to the felloe or rim, with greater security than had been ef- fected by previous methods, is the object of a contrivance for which William Howard obtained a patent, in February, 1830. Fig. 1527 shows a portion of a wheel constructed on this new method ; a, is the nave, of wood ; 6, 6, 6, wooden spokes, inserted into the nave in the usual , way ; c, c, is the rim or felloe, in- tended to be formed by one entire circle of wrought iron; d, and e, e, are the shoes or blocks, of cast iron, for receiving the ends of the spokes, which are secured by bolts to the nm on the inner circumference. The cap of the block d, is removed, for the purpose of showing the internal form of the block ; e, e, have their caps fixed on, as they would appear when the spokes are fitted in. One of the caps or shoes is shown detached, upon a larger scale, at Jig. 1528, by which it will be perceived that the end 1528 of the spoke is introduced into the shoe on the side. It is proposed that the end of the spoke shall not reach quite to the end of the recess formed in the block, and that it shall be made tis[ht by a wedge driven in. The wedge piece is to be of wood, as fig. 1193, with a small slip of iron within it ; and a hole is perforat^ in the Uck of the block or shoe, for the wedge to be driven through. When this is done, the ends of the spokes become confined and tight ; and the projecting extremities of the 1529 wedges being cut off, the caps are then attached on the face of the block, as at f":g €, e, by pins riveted at their ends, which secures the spokes, and renders it ■—-^ impossible for them to be loosened by the vibrations as the wheel passes over the ground. One important use of the wedges, is to correct the eccentric figure of the wheel, which may be readily forced out in any part that may be out of the true form, by driving the wedffe up further ; and this, it is considered, will be a very im- portant advantage, as the nearer a wheel can be brought to a true circle, the easier it will run upon the road. The periphery of the wheel is to be protected by a tire, which may be put on in pieces, and bolted through the felloe; or it may be made in one ring, and attached, while hot, in the usual way. Mr. Reedhead's patent improvements in the construction of carriages, are represented in the following figures. They were specified in July, 1833. Fig. 1530, is a plan or horizontal view of the fore part of a carriage, intended to be drawn by horses, showing the fore wheels in their position when running in a straight course; fig. 1531, is a similar view, showing the wheels as locked, whei. in the act of 1530 1531 I turning; fig. 1532, is a front end elevation of the same ; fig. 1533, is a section taken through the centre of the fore axletree ; and fig. 1534, is a side elevation of the general 942 WHEEL CARRIAGES. WHEEL CARRIAGES. 943 m^ appearance of a stage-coach, with the improvements appended ; a, a, are two splinter- bars, with their roller bolts, for connecting the traces of the harness ; these splinter bars ire atlached, by the bent irons b, b, to two short axletrees or axle-boxes c, c, which carry Ihe axles of the fore wheels rf, d, and turn upon vertical pins or bolts «, «, passed through the fore axletree /, the splinter-bars and axle-boxes being mounted so as to move parallel to each other, the latter partaking of any motion given to the splinter-bars by the horses in drawing the carriage forward, and thereby producing the locking of the wheels, as shown in Jig. 1531 ; and in order that the two wheels, and their axles and axle-boxes, together with the splinter-bars a, "ted with water as soon as it is formed, and bein? decanted ofF quite hmpid, is exposed to a current of carbonic acid gas, which, uniting wiFh the two "r^i^y'T^'T "^M'^^lf f '"^V" '^' subacetate, precipitates them in^he form of a Iv hp .vt • t^'iT ''' '\^ r'^ ^r "'^^ ^ ^^'"^*y ^^^^"'°"s ^<^^tate. The carbonTc acid T^l Lit rTt T f ^-^'^/i ''\'''^'' compounds, or venerated bv combustion of cha i- IZt'.tlln . K ?' T- '" '^r >'i'r ^^^^> it must be transmitted through a solution cl acetate of lead before being admitted into the subacetate, to deprive it of anv particles o wXettl^ do'w^t^^^^^ ^'''' l'' precipitation of the car'bonate of lead is completed;Ld well settled down, the supernatant acetate is decanted off, and made to act on anithei WHITE LEAD. 947 dose of litharge. The deposit being first rinsed with a little water, this washing is added to the acetate; after which the white lead is thoroughly elutriated. This repe- tition of the process may be indefinitely made; but there is always a small loss of acetate, which must be repaired, either directly or by adding some vinegar. In order to obtain the nnest white lead by the process with earthen pots containing vinegar buried in fermenting tan, and covered by a grating of lead, the metal should be so thin as to be entirely convertible into carbonate; for whenever any of it remains, it is apt to give a gray tint to the product: if the temperature of the fermenting mass is less than 90*^ Fahr., some particles of the metal will resist the action of the vinegar, and degrade the color; and if it exceeds 122°, the white verges into yellow, in consequence of some carbonaceous compound being developed from the principles of the acetic acid. The dung and tan have been generally supposed to act in this process by supplying carbonic acid, the result of their fermentation ; but it is now said that this explanation is inexact, because the best white lead can be obtained by the entire exclusion of air from the pots in which the carbonation of the metal is carried on. We are thence led to conclude that the lead is oxidized at the expense of the oxygen of the vinegar, and carbonated by the agency of its oxygen and carbon ; the hydrogen of the acid being left to associate itself with the remiining oxygen and carbon, so as to con- stitute an ethereous cotnpoani: thus, supposing the three atoms of oxvgen to form, with one of lead and one of carban, an atom of carbonate, then tl"»e remaining three atoms of carbon and three of hydrogen would compose oletiant gas. It is customary on the continent to mould the white lead into coni^'^ "^^""^te of lea* neutral nitrate, by thi agency of Jhe cVrbon c add JI V^jnsformed into carbonate anA of white lead produced by precinUa^^^^^^ f a '^''- ^^^^^^^^''ed that all sortw dition ; appear.^therefore, sLfi^C ^nL Xn y]Xd^ '" • ««'"^-<^^^«t«"'ne con- cover so well as white lead made by lie tnof.^ 1^7' ^'^^ J">croscope ; and do not has remained always solid durinl its tranC'nn f ?u^^^\ ^""^ ^«"' ^" ^^'^^' the lead hence consists of opaque parSf ''""'^''^^ ^^"^ ^he blue to the white state; and anto?h1:rfoTL\t^:£;^^:rbvriiJa't''' ^^/^^^ ^,^P^'«^^ ^-^^-^ine Torassa or barrels.' along with^^ate;. and e/posin' th^mLf^ "V' I'^T'*^ «'' «^-^> '" ^r^yi air, to be oxidised and carbonate?^ It"? said ^w^^^ water to the expended at Chelsea, by a joint stock comZ :*„^f "^^"'"^ "^ 100.000/. have been the nreceding most opilose'and d:tuvT7oi; "-'J?^^ ^^ --"^ing tried without success in Germanv T amLn,,; i n l!t ^^ *'®^"' ^""7 Jeara ago. jects for preparing white lead ar; inferL^n . ^'^"^ *^/ ^^^^^ ^^ these^-ecent p?o: old Dutch pWs^s which r^arb so ara^^^^^^^ q^^^ty of produce, to^the thoroughly into the best white lU.w thin £~ ^^ ^'"« ^^^^ than by any other plan. ^^^^ ^*^ ^^ ^«3'«> at less expense of labor is a''tt'^rb;>rat:'^Ie'i;{t!:.'tl?t::7„"l!''' ?-t»tV-baoetate. and subnitrat, oxygon 8 and one of csrboTJ'Sl^-^^llZ^^^, IZ'TV^ !"'"' '"*• »"* <>' compound; or, of lead, 77-6- oxvfen «• 1,1 • 'o *' "'* «'»""<= height of the been supposed, by so^; auth'orftfat' thi de„r«„^'t' , '''= '" ^'^ P""^' '' h"' Krems and Holland is a kind of subearbon-te con^nin- iT"'"^ *'"" '"''d »' preparation of sulphate of leadfaTplS^^ Tit""' ^" ^^^^'"^^^' ^839. for a bonate is applied. His plan is to put 56 L n/= ^fl i *^.\P"'P««^« to which the car- with one pound of acetic Lid (and water^n^r.-fi ^''^- ^'^^^'-^ '"^to a tub, to mix it ture till the oxide of lead becomes LLcetaL "^ Bat IT''^' ' '^t^' ^'^^ *« ^^^^^te the mix- fected, he pours into the tub, t ^ra pfDe siifnhn^^ "^rV^'' "-^^"^^ ^« P^tially ef. the rate of about 1 pound per m?nutP Si ' ^i ^^ ^cidof specific gravity 1-5975, at been added to convert aUthrie^d into T . n"^ 't T"^ ^"?:"^"3^ «^ ^^P^^^c acid has of the litharge. The sulnhate if^ftor !i ^''''i^ !. ^^'°= «^°"t 20 parts of acid to 1 12 I have examined {he parties of thYsThtrT^^^ "f ^"^^> «*«^^« ^°^ the market and found them to be sem ^crysUll ne nndJZf. "'"'^ ^ good achromatic microscope carbonate.precipitated from sSine'tl^urns ofThe meTa?""^' ^^'^ ""'' ^^^ ^"^^^^ '^ a earion:rCmTs^oliL?or'tr^^^^^^^^ tKT^T^^^^ ^^^^ ^^ P-^P^tatin. ammonia. On this process in » ™ • , • the metal by means of carbonate of In Liebig ^n,w:e^:Xy:n:^:ZTM^^^^^^^^ »>e-dt investigation of two sorts of lead prepared in th' n / k^'"^ ^t' communicated his vinegar and carbonic acid upon metallic IphH ,ni *?"^^ "^^^^ ^^ ^^^ «^«^^ action of The one sort was manXt^rpTlJ^ ' u^"" *^^ ^^^* ^^^^^^"ti He also examined 3 rpedmensoA ^^ ^lagenfurth of xlemf * position; affording Harper cent of cSn'^ '^^^^^^ ^S'-eed in com ing to the formula, 2 (PbOrco'Up^O h'(^^^ correspond- carb onate of lead with 1 atom of oxide and ?' / ^V ''' '" ^°"^^' ^ atoms of thus,¥3rmH-112-f-9. ^ ''^°"' of water-in round numbers, Mulder observed specimens of whii*. i^-^ r j/». bonate, oxide, and water/from the T^ve if^' f ^'A^rent atomic proportions of car. the carbonate increased. The whhe lead bv thTnT'i **^^' '^^ ^""^'ty improved a. Blackett of Newcastle, is certaTniy suSor Is « ''^ P'^'T^ made by Messrs. Its particles are amorphous and opaque covering oil pigment to all others. inthrrnSt^erj^^^^^^^^^^^ of magnesia in water impregnated wi\h carWc " Hd\'''''T^' m dissolving carbonate limestone or other earthy substances conSJirng m^^nfS IS' a^^^^^^^ WHITE LEAD. 949 rough hydrate of magnesia in the mode hereafter described, and in applying this solu- tion to the manufacture of magnesia and its salts, and the precipitation of carbonate of lead from any of the soluble salts of lead, but particularly the chloride of lead; in which latter case the carbonate of lead, so precipitated, is triturated with a solution of caustic potash or soda, by which a small quantity of chloride of lead contained in it is converted into hydrated oxide of lead, and the whole rendered similar in composition to the best white lead of commerce. The manner in which these improvements are carried into effect is thus described by the patentee : I take magnesian limestone, \v1iich is well known to be a mixture of carbonate of lime and carbonate of magnesia, in proportions varying at different localities; and on this account I am careful tc procure it from places where the stone is rich in magnesia. This I reduce to powder, and sift it through a sieve of forty or fifty apertures to the linear inch. I then heat it red hot, in an iron retort or reverberatory furnace, for two or three hours, when, the carbonic acid being expelled from the carbonate of magnesia, but not from the car- bonate of lime, I withdraw the whole from the retort or furnace, and suffer it to cool. The magnesia contained in the limestone is now soluble in water impregnated with carbonic acid gas, and to dissolve it I proceed as follows : I am provided with an iron cylinder, lined with lead, which may be of any convenient size, say 4 feet long by 2^ feet in diameter ; it is furnished with a safety-valve and an agitator, which latter may be an axis in the centre of the cylinder, with arms reaching nearly to the circum- ference, all made of iron and covered with lead. The cylinder is placed horizontally, and one extremity of this axis is supported within it by a proper carriage, the other extremity being prolonged, and passing through a stufling-box at the other end of the cylinder, so that the agitator may be turned round by applying manual or other power to its projecting end. A pipe, leading from a force-pump, is connected with the under side of the cylinder, through which carbonic acid gas may be forced from a gasometer in communication with the pump, and a mercurial gauge is attached, to show at all times the amount of pressure within the cylinder, independently of the safety-valve. Into a cylinder of the size given I introduce from 100 to 120 lbs. of the calcined lune- stone, with a quantity of pure water, nearly filling the cylinder ; I then pump in car- bonic acid gas, constantly turning the agitator, and forcing in more and more gas, till absorption ceases, under a pressure of five atmospheres. I suffer it to stand in this condition three or four hours, and then run off the contents of the cvlinder into a cistern, and allow it to settle. The clear liquor is now a solution of carbonate oi magnesia in water impregnated with carbonic acid gas, or, as I shall hereafler call it, a solution of bicarbonate of magnesia, having a specific gravity of about 1*028, and containing about 1,600 grains of carbonate of magnesia to the imperial gallon. I consider it the best mode of obtaining a solution of bicarbonate of magnesia from magnesian limestone, to operate upon the limestone after being calcined at a red heat in the way described ; but the process may be varied by using in the cylinder the mixed hydrates of lime and magnesia, obtained by completely burning ma?nesian limestone in a kiln, as commonly practised, and slaking it with water in the^ usual manner ; or, to lessen the expenditure of carbonic acid gas, the mixed hydrates may be exposed to the air a few weeks till the lime has become less caustic by the absorp- tion of carbonic acid from the atmosphere. Or the mixed hydrates may be treated with water, as practised by some manufacturers of Epsom salts, till the lime is wholly or principally removed ; after which the residual rough hydrate of magnesia may be acted upon in the cylinder, as described ; or hydrate of magnesia may be prepared for solution, in the cylinder, by dissolving magnesian limestone in hydrochloric acid, and treating the solution, or a solution of chloride of magnesium, obtained from sea-water by salt-makers in the form of bittern, with its equivalent quantity of hydrate of lime, or of the mixed hydrates of lime and magnesia, obtained by completely burning magnesian limestone, and slaking it as above. When I use this solution of bicarbonate of magnesia for the purpose of preparing magnesia and its salts, I evaporate it to drjness, by which a pure carbonate of magnesia is at once obtained, without the necessity of using a carbonated alkali, as in the old process ; and from this I prepare pure magnesia by calcination in the usual manner ; or, instead of boiling to dryness, I merely heat the solutcn for some time to the boiling point, by which the excess of carbonic acid is partly driven off, and pure carbonate of magnesia is precipitated, which may then be collected, and dried in the same way as if precipitated by a carbonated alkali. If I require sulphate of maimesia, I neutralize the solution of bicarbonate of magnesia with sulphuric acid, boil down, and crystallize ; or I mix the solution with its e^ivalent quantity of sulphate of iron, dissolved m water, heated to the boiling point, and then suffer the precipitated car- bonate of iron to subside; after which I decant the clear solution of sulphate of mag- nesia, boil down, and crystallize as before. When using this solution of bicarbonate of magnesia for the purpose of preparing carbonate of lead, I make a saturated solution of chloride of lead m water, which, at the temperature of 50* or 60» Fahr., has a specifi- 950 WHITE LEAD. dktdvDLiLatP?^Tt^^^^^^ when carbonate of lead is imme- aiately precipitated; but in this operation I find it necessary to use certain wecautiona T^rtZZ ^ ^^r'^"'^^^" ^'?^"''*5^ °^ '^^"""^^ «^ ^^^d is carried down a"onc. wiUthe ^^d r.n;.n /'^ precautions are, first, to use an excess of the solutioh of mitnesil and secondly to mix the two solutions together as rapidly as possible Aslo the first, when using a magnesian solution, containing 1,600 grs VcaKate of maone^a r^^^^^r^V^.;""?' ^^'^ ^ f.^"^^^'^ «^ ^^^""'i^ «^ ^^^^ saturated at 550 or erfahr 1 measure of the former to 8| of the latter is a proper proportion ; in which case thprp LIL'^^'T. ""^ 'f ^'"f ? ^^ '^^^"^^^^ ^™P^«y^d> amounting to about an eUTof the Ota quantity contained in the solution. When either one or both the solutions vlr^ preliminary trials. It js not, however, necessary to be very exact, provided thern ii twTml o^w'tf '"^"""'^ of magnesia amounting to^froronTI^hl to^^^^^ Su^ wm rLirLc^';!'"^"^''''- '^''^ ''.^''' ''F''^''' than oSe eighth no T; f7*i, A ^^P^ ^^^ unnecessan' expenditure of the magnesian solution til *^\'T"^ precaution, of mixing the two solutions rapidly to|ethS it mav be accomplished variously; but I have found it a good method to run them S two 'r^Z^f'^'^'TiV'^l''''^ ^" quantity, into a small cistern Tn which they are to Te rapidly blended together by brisk stirring, before passing out, through a hole In the XZl thn^ ^^kP- 'T^"" ^^ *""^' ^^^^« '^' precipitate finally settles. The pre! if i a c^Jbonat n?1 '', '" ^' '''^\''''^' ^^^^^^ ^"^ ^^^^^ ^^ ^^^ usual manSS ilJL«T ♦ ^ lead, very nearly pure, and suitable for most purposes: but it SJZf t T'""' ^ «°^a» portion of chloride of lead, seldom less than from 1 to 2 Tthe olo?%rbX o'f Th"'';r. ". 'Vr'' ^ ^'^'^"^^^y^ ^^ somewhaJTnjirious it into TLa . A ^'f V^^, "^l"'^^ ^^^*^- ^ decompose this chloride, and convert of caustic aka^'ln'f 'n^ni '-^ ''^ ^^^^'^^^ ]!»^ ^^ P-<^^Pitate wiih a so'utfon Ip-.lwfth .fi ir • ""'" ^'™'^^'" ^'^ ^^^ ordmary mill used in grinding white le-.d with oil, adding just so much of the ley as may be required to convert the nip nf wf ilT'*' ^ '''? ^"''"- ^ ^"°^ ^^'« P^^te to lie a few da?s, after whTch! the chlo?[de' formed ^i" th?'''' V' "' ^^TV^"-*'^^^^ decomposed, I wash 'out the alkal ne chlor de whhe le^d l^^'''*^^'^"' *^d obtain a white lead, similar in composition to the best I« J of commerce I prepare the caustic alkaline ley by boiling together in a the sediment, must be kept in a close vessel for use As we have before hinted, the manufiicture of white lead bv the Dutch process is one the nature of wh.ch seems yet enveloped in considerable obscurity. So far asT^^^^^ go the action wou d seem to consist; first, in the oxidation of metallic lead by ?he atml sphere, under the influence of the vapor of acetic acid; secondlv. in thrpri^uction o7 acetate of lead, by the combination of the oxide of lead w th the acVticacid- and t h-dlJ m the displacement of the acetic acid from its union with the ^xide of lead by th^^ action of carbonic acid, and the consequent formation of white lead But thisin no w^v accounts for the fact, that, when acetate of lead is decomposed bj'trbonL ac d it Ca^ bonat^e of lead and not white lead, which is formed. Nor can we conceive how ^ another acid incapable of completely saturating the oxide. In other worS^ L^wh"tf I^ uoL leinain uimea to this if We confess our inability to reconcile the facts nf tb^ n«^tvnor,r!r:^ftu'..u P"^**^"*^^'?" and the formation of whit^ lead. "'^ '^''^' "'^'*'" ""^ ^^'^ ^^ eremacausis. The apparatus employed in the manufacture of white lead is extremely simple and consists merely of certain large enclosures or spaces, called beds, in wS t^he sUcU are bu.lt up; together with the earthenware pots needed for holding tWe >regarand the msi ■Akrtk^Hata tfUi WHITE LEAD. 951 machinery used in casting the lead and grinding the white lead, so as to fit it for the market. The metallic lead was formerly used in the shape of sheets or coils, which were placed perpendicularly over the vinegar pots ; but this practice has been almost everywhere abandoned, and at present the lead is generally cast into what are called "crates" or "grates," of about 9 inches square, and having the appearance of lattice* work; the object being to expose as large a surface as possible of metallic lead to the action of the vapor of the vinegar. The beds are of considerable size; and, in this re- spect, some diversity of opinion prevails amongst practical men ; but it seems pretty certain that no advantage is gained when the area of a bed comes to exceed 300 square feet; and there are many reasons for believing, that, with beds of twice this area, the gain, in point of diminished labor, is much more than compensated for by the reduced produce in white lead. Nevertheless, each manufacturer seems to entertain an opinion of his own in respect to tliis matter ; and there are even some pretensions to secresy concerning it In fact, everything depends upon the construction of the bed, for it is this which regulates the production of white lead; and as a proof of the great im- portance connected with this circumstance, we may here mention, that, \vhilst one manufacturer has produced as much as 65 per cent, of corrosion during a long course of years, anoUier in his immediate neighborhood has never been abled to exceed 52 per cent The beds of the former are 16 feet square, whilst those of the latter are 19| feet square; and, in dwelling upon the details of this operation, we shall find tliat theo- retically, a bed may be tx>o large, as the above practical fact indicates. Similarly it can be shown that a stack (which is merely a series of beds) may be too large; and ex- Seri^-nce has convinced us that a stack containing more than eight beds is to be con- emned ; and, as a general rule, six should be preferred, except where want of space renders a different line of manufacture indispensable. In forming a stack, it is necessary to begin by laying, in the first instance, a bed of spent tanner's bark, 3 feet in thickness, over the surface of the bed ; and upon this are placed the eartlienware pots containing the vinegar. These are arranged, side by side, and filled to about one-third of their contents with vinegar, of a strength equal to 6 per cent of anhydrous acetate acid. Upon these pots are placed the crates of lead, and over all a series of boards are arranged, which form a floor for the next layer of spent tan.* Such an arrangement as we have described, is denominated "a bed," but there is this difference between the beds, viz., that the lowest or bottom bed has a bed of tan 3 feet in thickness, whereas but 1 foot is needed in the others. Having finished the lowest bed, 12 inches of spent tan are now placed upon the bo-^rds, and a similar arrangement of pots, crates, and boards, takes place, which constitutes the second bed; this is fol- lowed by a third, a fourth, and so on, until at last the uppermost bed is finished ; when a layer of spent tan, 30 inches in thickness, is placed over the whole, and the operation may be said to commence. In six or eight days the tan begins to ferment and evolve heat; and this goes on increasing for some weeks, when it gradually diminislies, and at the end of about three months the whole has become cool, and the stack is fit to be taken down. When examined, the pots, which formerly contained vinegar, will now be found to be quite empty, or to hold a little water merely, but no acetic acid; the leaden crates will be discovered to have increased sensibly in bulk, to have become coated with a thick and dense incrustation of white lead, and in some places even to have become altogether converted into this substance ; w^hilst the tan, having lost its fermentative quality, is now useless, except for fuel. The successive beds constituting the entire stack are next carefully removed, so as to obtain the white lead with the least possible admixture of the tan; and as a portion of this substance always adheres to the crates, these are washed in a kind of wear or trough, by which the whole of the tan is thoroughly separated. When this is seen to be com- plete, the corroded part of the plat^ or "white lead" is detached from the uncorroded or "blue lead," by means of slight taps or blows with a mallet The blue lead is weighed, and, for the most part, remelted and again cast into crates; whilst the white lead is first crushed, and afterwards ground in wat^r into a fine powder, when it is col- lected by elutriation and deposition, and dried in stoves, a little below the boiling heat of water. Formerly this grinding was performed in the dry way, and much injury to the health of the workmen thus resulted; but, during the last 20 years, the wet mode of grinding has become general, and is greatly to be preferred. The conversion of white lead into paint is a simple mechanical operation, though, as we have before remarked, it is followed by chemical results; for there can be no doubt that the surplus oxide in the white lead combines with part of the oil employed to form the paint, and gives rise to a true plaster or metallic soap. The proportions of oil and white lead vary with different manufacturers; nor does it matter much what these proportions are: the principal point is to obtain a thorough intermixture of the two ingredients; and this is done by grinding them together beneath heavy stones or " runners," for several hou»-s, at the end of which time the mixture wUl be found oomogeuoua T 952 WINDLASSES. The most probable explanation is cerUiin v tl^i? no sal.ent feature to guide our inquirf pre-existence of sex-basic acetate of [e^d ^1 tL«l"'' r^"' f"^ ^'"^^^ supposes tb^ which prove that this substance is canabie nfnn ^^ *V™^ ^''^''^ «'* "<> experiments to complete the argument But then thL i^s n "/n" T'?F ^^" ^'^^ ^^ombustion^reS sohuion; and there are many LaWour/aerf^^^^^^ eremacausis or combustion heVe hintfnf Ta ^'''^'"^f^^y ^hat warrant the kind of atom of the sex-basic acetate of ead and eitu r'""'^"^ '^"'^ ^^ be correct, th„ one unite as in the following diac^ram and nrod!,./f "' ?^ atmospheric oxygen, wouM atoms ofwater.twoatom^sof^whl^Lwlf;^^^^^^^^^^ consisfa /\f WINES. 953 sex-basic 1 -i acetate of lead i consists of 6 oxide of lead 4 earlon 3 hydrogen 3 oxygen 8 oxygen 2 hydrated basic carbonate of lead or white lead 4 carbonic acid. :sf "F'X '"^^""'■^'•-^^ kind oT IL^eato of lead, under the influence of a gentle hpn/ K?/ .. * ^'^'' " '"''^e excess of litharge oan , Connected with this siS is th« K^^/"^, /'»"«/<>" verted into white lead ^ ' "' lead or oxychloride, which^ s nov. eont^f^^^^^ "''''^' """'^ '^'' «ub cM,,;^, ^f oxychloride is so constituted. tTaTJ^for fw"^:,"'" as a substitute for white lead The we substitute two atoms of c'hloride oM^nTn ' f ^"'"bonate of lead in white lead which has been made the sub l^'o :Utenttv Mr" H"p^^^ ^'" "^^^ eompound. and T^ne. Xow ,t is a very remarkable flfand .JonJw ' ^«"'"««'». of Ne wcastle-upon- we have here advanced, that the nerpkfnt "cov^6^ corroborative of the views which lead, just as its basic composition woi^d fn l«f ^ ^ T""^ '''^" ^'^h the best white of Jead contained in it uniTes to pm of th. In V.k "^ ^^' probability is, that the oxide Boap ; whilst the chloride of lead remains in ^' ^1"'"^' ^^^''"'"^ «« before a meta lie opacty and whiteness. An observaTonUl"^:^^ '" ''''' T": ^"^ eommuni cat . Ure. shows the correctness of such a conclut^An f 7f' '" ^^^ ^''^ '"«tance by Dr chloride of lead be quite insoluble in wate'vI?aV.?;' S''^""^^' ^''^" «J«°-. ^heUy readi y dissolves from the mass the chbr Je ohII "^/"'^ture with oil, boiling watfr ^at paint made with an insoluble salt, like carboLln'^^'*"^' '"""^^ "'«<> *« «bow. with a soluble salt, like the chloride Exoprlpn? ^^"^' '' P'-^^'erable to one madi cotton threads, which b/ctpilfary alL'on drawTm^fhr-,' "'r"^ '"^^^ ^^ ^o^ «P"n W, or wax in candles, in small successive port on! fn7 'I ^"'"'1^'' °^ ^be melted tal- and tallow candles, the wick is formed o^parX X'i^ ^ ^''T'^' ^" «^"^"^'>" wax Wick isp aited upon the braiding machrnp'^ml'!f "T^'^V "> the stearine candles the and dried, whereby, as it burnsjt fait to or.rr'^'"'''' " ^^''^^"^ l".r^fK '" '^^ P«^^"^ ««ndl so Mr Palmer on'pf T^r^ ^'^^-'^ requiring ^ With subnitrate of bismuth ground ud wiVh ^f'^ *t"^,^ ""^ ^be wick is first imbLd tTi:r;r"^? ^•-i>%; anf^rthis^wrci tw Lv he'i'^^'n'' v'^? '^^"^^ rounJTn td twisted double round a rod, like the Z^.2^.^^lfxr ^^"^^b of the intended candle la inserted in the axis of the eandle moujd Ts^K^^^^r ™^ ^''^ ^^tb its c^il bein ' low; and when the tallow is set tL J.^' ' . u^ enclosed by pouring in the melted fT U.e candle. As this candTeL burned the end, %^m ^5 ''t ^' ^«P' braving tS^Bw^k^" beyond the flame; and the bisSh attachpd f I "'' ^^"^^" "^'^^ ^^and out siJewava T?^ 't «^™««Pbere, causes the wic "tote co'l'tT'''" ^'*"^ «^^^^ ^" by the oxy! '^'wr'ei'H^^ ^^ «""ffi"^ it- completely consumed, and, therefore s^vei, WIXCING-MACHINE is iha v v x. horizontaUy by the endtontTLf fx;:^n Crfn^^^^ ^^^^? '^^^' ^bich he suspends the hue of the axis, being placed ovp^fj, . ?I "^S^' ^^er the edge of his vat sTt^of the pie«e of cloth ^hich fs Cunl Ton the rl': ' ^''''T '"^ ^bfcoppe w i ', t^rmi partment of the bath, according as i^ turned bv^ descend alternatel/fnto ei &„ having the windlass upset With this mr.K; ^^^ 'bip without the possibilitv nf beam, polygonal in transverse section, acting horizontally at right angles to a line bi- secting the ship from stem to stern, and working in, and bearing upon, stancheons, called "knight-heads," strongly fixed to the ship's deck and deck-timbers immediately abaft the foremast The use of the windlass is to raise or weigh the anchor, by means of the cable, which is made to take a turn round the windlass beam, whose spindle shape enables it to present itself at right angles to a line drawn from either hawshole, under which the anchor may lie, for the ship is hove short upon her anchor by means of the more quickly moving, but less powerful capstan, before the windlass is called into action. The "purchase" of a windlass is the power applicable to work it, or rather the means provided, as the handspike levers in ordinary use, of applying the power of the men to turn the beam, and wind or hoist up the anchor by its cable. Nothing can exceed the simplicity or strength of the ordinary ship's windlass, having regard to the size and strength of the ship herself: but there is room for improvement in the power and in the speed of a windlass, and the means of doing the same work with fewer hands would be a great advantage. A^INE, is the fermented juice of the grape. In the more southern states of Europe, the grapes, being more saccharine, aflbrd a more abundant production of alcohol, and slronajer wines, as exemplified in the best port, sherry, and madeira. The influence of solar heat upon the vines may, however, be mitigated by growing them to moderate heights on level ground, and by training them in festoons under the shelter of trees. In the more temperate climates, such as the district of Burgundy, the finer flavored wines are produced ; and there the vines are usually grown upon hilly slopes front- ins the south, with more or less of an easterly or westerly direction, as on the Cote d'Or, at a distance from marshes, forests, and rivers, whose vapors might deteriorate the air. The plains of this district, even when possessing a similar or analogous soil, do not produce wines of so agreeable a flavor. The influence of temperature be- comes very manifest in countries furiher north, where, in consequence of a few de- grees of thermometric depression, the production of generous agreeable wine becomes impossible. The land most favorable to the vine is light, easily permeable to water, but some- what retentive by its composition ; with a sandy subsoil, to allow the excess of moisture 10 drain readily ofl". Calcareous soils produce the highly esteemed wines of the Cote d'Or ; a s;ranite debris forms the foundations of the lands where the Hermitage wines are grown ; silicious soil interspersed with flints furnishes the celebrated wines of Chateau-Nv,uf, Ferte, and La Gaude ; schistose districts aflTord also good wine, as that called la Malgue. Thus we see that lands difl'ering in chemical composition, but possesse 1 of the proper physical qualities, may produce most agreeable wines ; and so also may lands of like chemical and physical constitution produce various kinds of wme, according to their varied exposure. As a striking example of these effects, we may adduce the slopes of the hills which grow the wines of Montrachet. The insulated ,>art towards the top furnishes the wine called Chevalier Montrachet^ which is less esteern«;d, and sells at a much lower price, than the delicious wine grown on the middle height, called true Montrachet. Beneath this district, and in the surrounding plains. Che vines aflford a far inferior article, called bastard Montrachet. The opposite side of the hills produces very indilfereni wine. Similar differences, in a greater or less degree, are observable relatively to the districts which grow thePomard, Volnay, Beaune, Nuits. Vougeol, Chamberlin, Romance, &c. Everywhere it is found, that the reverse side 01 the hill, the summit, and the plain, although generally consisting of like soil, afford infe- rior wine to the middle southern slopes. Amelioration of the soil. — When the vine lands are too light or too dense, they may be modified, within certain limits, by introducing into them either argillaceous or sili- cious matter. Marl is excellent for almost all grounds which are not previously too calcareous, being alike useful to open dense soils, and to render porous ones more reten- tive. Manure. — Fcr the vine, as well as all cultivated plants, a manure supplying azotized or animal nutriment may be used with great advantage, provided care be taken to ripen it by previous ferinenlalion, so that it may not, by absorption in too crude a state, impart any disagreeable odor to the grape; as sometimes happens to the vines grown in the vicinity of great towns, like Paris, and near Argenteuil. There is a com- post used in France, called animalized ft/ac/f, of which from one fifth to one half of a litre (old En^:lish quart) serves sufficiently to fertilize the root of one vine, when applied every year, or two years. An excess of manure, in rainy seasons especially, has the effect of rendering the grapes large and insipid. The ground is tilled at the same time as the manure is applied, towards the month of March; the plants are then dressed, and the props are inserted. The weakness of the plants renders this practice useful; but in some southern districts, the stem of the vine, when supported at a proper height, acpuires after a while sufficient size and strength to ===3= i 'I i 954 WINES. the spring rains hare washed it down Thl r. • " , ^^ ^'^^^^^^ over with soiJ aft^r repealed after maceialin" the J»iU> "^«»'''"?. "Peralion beains, which is nsS has softened the texture of the sS 1,1 .k""?'' "■'""' "■""» «" "'= Pie "t Lmentaill^ grapes are collected i^ the va, ,he „ice h-? '"" ''<■'"• ^^^"^ '"« whole bS M s.h-n'^V" ^""^^ "Wtoas, were the mo» hs «? .h.f'"' '" ""* '"Pi '>'" '' »'ou|<| M. Sebille Attger introduced with ^ucces, hT.^L ,■ u""' "?'' ■=<""«•• With this view wtrT'"' "'■"'" Maine-et-Loire '^"" """" '" ">« ■""""fecture of wineTa « it eea«st;Tttm'ltuo"„fS"he''wif "'"'"'■■"" ""'^ »•"« >««» 'e.ula,ed as soon be racked off from the lees" by means oH V "",' ""I'"'''' ^-'-^h^rine or'muddy' "S marc being then gently scueeLn In . -'l"?"'. an tHe casl. . . a proof of th. uniform temperature in summer aadwter and biaTsLh^Tn"^ '' V""''''' «*»-«••'' highway or street as not to suffer vibration from .. f-^ a distance from a frequented Wines should be racked off in ^Ini .k ^.'''^ "'*'^"'" o^carria-es. ^ ^ for light wines. St."n"s ^r^^^^^^^ off^ml^'^h^'"^^^ 'f^^^ ^^^ «»-» time months upon the lees, to promote the' slow ort,ensihl7r "^^ '^"^^ ^ ^'^^^ ^'^ ^'?»»teen managed serves beiter than a faucet to draVoff wrnf ll'T'^^''^^"' ^ ^>'P^«" ^^e" wines, before being bottled, should be fined wi^hi.Tn".! ^T '-^^ s^^i^^ent. White with whites of eggs beat um into a n-nt h !n i • '^'"":"Jass ; red wines are usually fined water. But sonTe^trong wine ^ ^h e tare"a iTtlLl ^'^^^ ^j'"^^ '"^^^ ^""^ «? sho^w{f :Si;t^^^^^ "^ ^^^^^'^ ^^*"^^^ °t^^.cary of Nantes, demon- fact it is the white wines, especially hose wS con ^^^i;' '^ ^'^"''^'^^ (^^"^^») «nd in ject to this malady. He' also poin ed out tT^n oTr ^I'^T ^''>'' V«""'"> w'^'<='' «re sub- under a rather agreeable form, nan:ely, U.e bruhTh.. ri? >\/" '^^ "^^'^^«" «^ ^«»«i*-» in a somewhat unripe state ; of which'in po ^tel^^^i^S^^^ n'i"^'"^'"-'^^? ^'""''''^^ After agitation, the wine is to be left in reLe for « di ' , ' sufficient for a barrel. The tannin by this time will have separated ihp„Lf- ,-' "' •'^°' ^"d t^^en racked off. moved , he ropiness. The wine il to^'b^red 'rndTS oil"" '^^" ^'^ "^""^> ^^ - ^«3r^LS?:tSSt^!;:i^ ^-^ --^ -i- had re. :ii:^:d ^;s ^i^rihii^-^^ eausj of t rr i^st::'^^;^-!;. f r s Accordin? to a statement in the Dirfinnttni^^ 'r i 7 . hectare of vineyard, upon tl/e averagf rnryTa^fl^^^^^^^ ^"""^^ P^^-^ ^^ a litres, which fetch 0-877 francs each, or 200 fraJcs .L .' r'noo ^ °^ ^^^"«>'' ^^ ^779 all to 1672 francs. Deducting for expenses and Mv!/^°^.^^.^ ^•^'^^' amounting in remain 1,100 francs of net proceeds tand as thev-^'- ^7'"'^^^^^*^ ^'^ ''^^ncs, there 23,000 francs, the profit tuJns out ti be no'no^e than% n'' '"''''"' "^^^ ^^ ^''^^^'^ at the growths of Beaune, Nuits, &c., does not excet 600 7 ''"'' \^" "^' ^''^^^^^^ ^« and therefore is equivalent to only 2h per cent unn^.n ^'^-"'f ^^' ^^^^are (2-4 acres). The quantity of alcohol contained inTfferem wines l^?!;""'* , k ' borate experiments by Brande and FontenelleV but as i r^n^" T'^'/^' '"^'J"*^^ «'' ^^«- , out as It must evidently vary with difler- WINES. 957 ent seasons, the results can be received merely as approximate. The only apparatus required for this research is a small still and refrigeratory, so well fitted up as to permit none of the spirituous vapors to be dissipated. The distilled liquor should be received in a glass tube, graduated into one hundred measures, of such capacity as to contain the whole of the alcohol which the given measure of wine employed is capable of yielding. In the successive experiments, the quantity of wine used, and of spirit distilled over, be- ing the same in volume, the relative densities of the latter will show at once the relative stren^tlis of the wines. A very neat small apparatus has been contrived for the purpose of analyzing wines in this manner, by M. Gay Lussac. It is constructed, and sold at a moderate price, by M. Collardeau, No. 56", Rue Faubourg St. Martin, Paris. The pro- portion given by Brande (Table I.), has been reduced to the standard of absolute alcohol by Fesser; and* that by Fontenelle (Table II.), to the same standard by Schubarthj ai in the following tables : — Table I. Name of the wine. Port Wine, Port Wine, Mean, Madeira Madeira, Sherry, Sherrj- Bordeaux, Claret, . . . Bordeaux, Claret, . . . Ca1ca\'ella, Lisbon, Malaofa, Bucellas, Red Madeira, Malmsey, Marsala, Mareala, Champagne, [rose],. . Champagne, [white], Burgundy, Burgundy, White Hermitage,.. . Red Hermitage, H«ck, Hock Vin de Grave 100 measures Sp. grav. contain at 00° F. Alcohol Absolute of 0-825. alcohol. 0-97616 21-40 19-82 0-97200 2583 2392 0-97460 23 49 21 75 0-97810 1934 1791 097333 21-42 22-61 0-97913 18-25 17-00 0-97700 1983 18-37 0-97410 12-9! 11-95 0-97092 16 32 15-11 0-97920 18 10 16-76 0-97846 18-94 1745 98000 17-26 15-98 0-97690 18-49 17-22 0-97899 18-40 17-04 0-98090 1640 15-91 0-98190 15-26 14-31 0-98000 17-26 15-98 0-98608 11 30 1046 0-98450 12-80 11-84 0-98300 14-53 13-34 0-98540 11-95 HOG C-9799C 1743 16-14 '3-9S495 12-32 11-40 0-98290 14-37 1331 0-98873 8-68 800 0-9S450 12fc0 1184 Name of the wine. Frontignac, Cote-Roti, Roussillun Cape Madeira, iTi uscai . ••.•»•«•. 9. ... Constantia, Tinto Schiraz, Syracuse, Nice, M. OlLo Vf ■■• •••• •••••••• Raisin Wine, Drained grape Wine,.. Lachryniae Cliristi, . . . . Currant Wine, Gooseberry Wine, Elder Wine, \ Cider, .,.,. > Perry, ) Brown Stout, ^V16f ••■•••••••••••«••• I oin6i f ••• ■••• •••••• •■ Rum, Hollands, Scotch Whiskey Irish Whiskey, Sp. grav, 0-98452 0-9S495 0-98005 0-97924 0-97913 0-97770 98399 0-98176 0-98200 0-98263 0-98760 0-97205 0-97925 0-97696 0-9S550 0-98760 98116 0-98873 0-93454 0-93855 100 measures contain at 60° F. Alcohol of 0-825. 17-79 12-27 1724 1811 Absolute alcohol. 16-25 19-75 13-30 1552 15-28 14-63 9-88 25-77 18-11 19 70 20-55 11-84 9-87 6-SO fees 4-20 5368 51-60 54-32 53 90 1184 11-36 15-96 16-77 17-00 1829 12 32 1435 14 15 1364 915 23 86 16-77 18 24 1903 1096 914 6-30 6-00 3«!9 4971 47-77 50 20 4991 Table II. Name of the Wine. Absolute alcohol. Name of the Wine. Absolute alcohol. Name of the Wine. Absolute alcohol. Routnllon {Eastern Pyrenees.) Rive-saltes 18 yrs. old BanvuUs 18 » Collyouvre 15 " Salces 10 " Department of the Aude. Fitoa and Lcu- catg 10 yrs. old 1 Lapalme 10 " 9-156 9-2-23 9080 8-680 8-568 8-790 Sijeau 8 yrs. old Narbonne 8 " Lezignan 10 " Mirepeisset 10 " Carcasonne 8 " Department of VHe- rault. Nissau 9 " neziers 8 " Montagnac 10 " Meze 10 " 8035 8-379 8-173 8-589 7-190 7-896 7-728 8-108 7-812 Montpellier 5 yrs. old Lunel 8 " Frontignan 5 " Red Hermitage 4 " White do. Burgundy 4 '• Grave 3 " Champagne (sparkling) Do. white do. Do. rose Bordeaux Toulouse 7413 7-564 7-098 6-838 7 056 6-195 5-638 5-680 5145 4-956 6-186 5027 WINES. In a case tried before the Court of Exchequer, at the instance of the Board of Customs, in December, 1843, of an attempt to obtain the drawback upon a large quantity of damaged claret offered for exportation, I had observed, in my examin- ation of the wine, that on the addition to it of water of ammonia to supersaturate its acidity, a lai^e flocculent precipitate of decomposed gluten fell, and the supernatant liquor lost its ruby color, and became yellow-brown. I have tried sound samples of genuine claret, very old, as well as new, by the same test, and I have found the ruby color to remain but little impaired ; contrary to the allegation oi the chemist of the 958 WINES. forfeited to the Crown. ^ ° admitted for drawback, and therefore ii^'J^SlZ, "^^1^:^^- ^' ''''' ^-^P- (-«-) or from langunge of the Excise, imder wS .,mpt?fS ^^t "^'"^^ «»•« ««^'ed *«r^i, in the the duties upon them ^e,^ replied asC^ro'st^the VV^'^P^'*^^^ '^' 1834, when revenue. The raisins called Lexiai are saTtonrod.'^' "S^ unproductive to the Denias a sweet wine- the Rln/^t ir^ s^'^ /<> produce a drj flavored wine- thfl andValeneias a Hch Td f^ tine 'yhe%?r ^^^^^^^^^ the red Sm^rt' the wine manufacture. The m^se^'of rlL ^ T -"^ ""P"^^" «'« ^^« Attest time for either beaten with mallets or crS./l/' ^^ bemg taken out of the packagca. Z then steeped in water in far'e vats ttw In l^?r^^^°^ ^ ^««-" t^m.^d^r! at top. The water being after some time drawn off^K ^T^ ".' *^^"om and another sure IS applied to the upper board to extract Xh V 1^^"" "°^ '"^^""^^ ^^"'^ Pre^ down through the false bottom, and flows oVLan'l"^^' '^''' "?""'''' which passes tuns. 'The residuary fruit is infused T.Ta^I-r^ i ^PP^^P^-^^te pipe into fermenting cess which is repeated till all ?hp!l «<^^'t'?nal water, and then squeezed- a m^ jected to severe^retr" fn^a^'srw^or^ Ty.t^f.^l'^:'^^^^^ ^^' "-P<^''' ^^-^ the vmous fermentation is occasionnllv L=LJf? ^i ^**® ^*°^' >^ the process of p>rove its flavor, and also trmS t'^^P?;;!'^^^^^^^^^^^ ^^f[-t body of the ra^pe to im Pm.JA.^^^''^^' «^«'''fi^d by being repeated vrT.^'ff aT'.'^ ?' afterwards set to . WINES, DEACIDIFICATICKV OF liL "" ' *°'^. ^°^^ ^'^'^ isinglass. Liebig* p«M|,hed in his^^n for* te March .^^^^^J /'.'""ar tiSe. Professor that ^^^uable object on old stored J?fal/w.M pf?'^ i^.n mitlel) for effecting wines," he says, "even of the mZtJT^l-^^l^ ^^'""® ^'"««- "Most of these tain a certain quanti; of free SrarK^'I^LT^^^^ "°^ ^"^ '*^^ ^^^^ condition, con properties depend T^ie iuicp nf llf ^'''^• ^^ ^ho8« presence many of their essential that of those of the youni Toots n Ta ""^ ^'^^^' ^^'^^^'"^ bitartr^te of potasT and of these sorts of grapes %ecom' erme'n .0^^? '\ T'^'J"^ ^'''^' ^^ ^he^n th 'must portionally as the alcohol increases a^fan^^ diminishes in solubility pro! deposit of tartar increases dtiringtL first year of 1 '"' .! ""^ V'^ '^' ^^^^^ ^W« becoming encrusted more and more w^th ils crvll ' "^^ ^^' ^^'' ''^'' *'^ ^^' ^*«^'» addition of the new wine to reXe^^at of tK ^-Ji"- T'T^""^ ^f the continual thereby acqVire\ a a^"e^\a?^ S^oTr^L' ."r ''^T.^^^J^^^^^^^ tarSc S? and deposited tartar. In the 8toHn|of many of th^^^^^^^^^ ^T^'^ "^ re-dissolving the at a certain period. By progfe^ivTfimnl nn fh '"^"^\f^^« '«rtar again disappears augment^ the taste and'^iaUfTthe ^ i'e^^^faLr^^^^^^^^^^ '^^^ proportiSSally ^me less af^reeablp in 11=0 a l ^ exalted, but the acid contents makp th^ mean of t^&:gt7riretZlZ: ^^a wXtfir "'"?"" "•ereforrweict::': of the wme. This mean is Dure nlnfr^f ... altering in any respect the quality centrated solution, is added tHnph^fl -^ ''^'' ""{ P^^^^' "^^^^ *'»« «alt, ?n con soluble tartar (one Dart of wh.-K -^"'"J as the above, there results the sparinZ temperature foH^ ai)thf^^^^^^^^^^ ^«, ^00 parts of water IZTnU'y as bitartrate from the liquid If we add to 10^^^^^^^^^ ' °^"^r«^««i<^ «"ears chiefly to be determined by the soil, and the condition and locality of the vineyard; and it is obvious that the qualities dependent upon these extractive matters cannot be replaced by sugar. It is of importance that the free acid be not removed before the fermentation, because on its presence during this process, as well as during the storing, depend the taste and principal qualities. WINE, FAMILY, may be made by the following recipe: — ^Take black, red, white currants, ripe cherries (black hearts are the best), and raspberries, of each an equal quantity. To 4 pounds of the mixed fruit, well bruised, put 1 gallon of clear soft water; steep three days and nights, in open vessels, frequently stirring up the magma; then strain through a hair sieve ; press the residuary pulp to dryness, and add its juice f 960 ¥ WIRE-DRAWING. s'«-t"i '^z[ rr rj: '"S3'' f T--- ^^^^^^^^^^ Cognac brandy, (but not the druled imka fon^n !f^-^ f "°."'' P"^ ^ q"«rt of g^oof and bung down. If it does not Hon be ome fine a s?.l? '^^"^r •^- ^j^'^ ^•«'" whiskey) into the hquid, in the proportion of VhTfiir' ^^^^P^"g of isinglass may be stirred that the addition of 1 o'. oHit™ of'LHl\f eT "^ '^ ? f"?"" ^ l-ve^fouol improves the quality of the wine and ZhL V ^,^"^° ^^ *'»^ fermentable liquor the grape. ^ "^ ^'^^' ^"^ '"^^^s it resemble more nearly the produce of Description. 1850. galls. alls. Cape French - .p. Canary, Fayal, Madeira, Portugal, Rbenieb, and Spanish • Total 234,779 600,243 8|469,290 1851. 407,158 764,931 7,836,336 Retained for Consumj.tion. Duty received. 1850. 9,304,312 9,008,420 246,498 363,483 6,072,637 1851. 234,794 -168,486 5,851,149 1850. £ a5,606 105,277 1351. 33,914 134,812 1,752,033 1,687,605 6,684.668 j 6,551,429 1,892.916 | ,,856,331 .n^bo'JL'Jof^v^in^' JaLt'"^^^^^^^^^^^^ obirS''.S^^^ ^-Y'-/, GciTn.) When an a steel plate so as to assume in its cross StlThrfor'" dim nishing apertures in hole, and to be augmented in length at the expense of i,f T T'^ dimensions of the last drawn The piece of steel called the Tl X//f. n" Y^""^''' '^ '^ ^^''^ *« ^^ wire. Jioles from the largest to the smallest • and he Lchrne for "^''^ '^ ^'^"^^^* ^'•«^^^^°» ^^ sion of the metallic particles to one another i. r^i.^r I ^^i" overcoming the lateral adhcv lay hold of the extremity of the wfre to null It .h ^5' ^raw^^nch. The pincers which to bite it firmly, by having the n^de'of tfe a v 'cm lil- '^^"^^^^^'^^^^^^' ^^^^ ^dlp S of giJt Silver down into stout wire, the hjS c pre t ^f ^^ For drawing thick tods advantage. ' ^ ^^^^^ ^^s been had recourse to with ■'^^^' 1540 represents a convenient form nff ho ^ i. by a ,„„„.e. „^ee,, p.-„.„, a„a ^XCrCL'^l^^^'iTill^^t,^^^^^^^^^^^^^ "" ing at a winch J the motion being so regulated by a fly-wheel, that it does not proceed in fits and stans, and cause mequahiies in the wire. The mTaJ requires to be annealed, now and the^ between successive drawings, other-' brittle for further extension. The reel r^ntTd'^'^'^^^^^^^^^^o^^etimel Deer, tor the purpose of clearing off' oxyde formed in the annealing, before the wire enters the dm^nln! ^'''*' ^"^ ""^^ «f' When, for very accurate purposes of science or thp L^fe ^"^'^l^- form wire is to be drawn, a Vlafe with one or Lretwe^edVn^ ^^"^'^ ^^ "«i- or more perforated rubies, sapphires, or chrysSues Jn !i v '' ^^^* ^'''' ^^'^^ ^^'tb one holes even in the best steel become Cidly wTder hv ?1 k""^ ^^ *''"''*^^ *«' ^^^^^^^ the ruby, 0.0033 of an inch in diameter, a'sH^er ^Tre ?70 mlln ^""1 l*''""^^ ^ ^"^^^ '"« « possessed at the end the very same section arLt til u"^' °"- ^^^ ^^^^ drawn, which weighing portions of equal length, as als'bv me^Uri^i'If;^^^^^^^ ^ ''^«"^t determined Ty an ordinary draw-plate of soft steel becomes so w^dp hv iT ^ micrometer. The hole in wire th«t it requires to be narrowed befoTe the oT ofnnf.l T'"" ^^'^^^ ^"^^°"^^ ^^ brass U n-e, by boir.g din.inlshe.l one half, one thirf ono ff'T ""^ ^^ "^^^" ^^^^'^ed! mented m length respectively, f.„„. ni .^ sKtt 'thnL "i" '4''' '" ^^^rr^^ter, is nu^r- may be prudently drawn ouCd.pends up^^ ^^du^^ ^ l^i^J^^thrt^^^lt; WOLFRAM. ;^1 may be always increased the more the wire becomes attenuated, because **t8 particlea progressively assume more and more of the filamentous form, and accommodate them- selves more readily to the extending force. Iron and brass wires, of 0-3 inch in diame- ter, bear drawing at the rate of from 12 to 15 inches per second; but when of 0-025 ( i ) of an inch, at the rate of from 40 to 45 inches in the same time. Finer silver and cop- per wire may be extended from 60 to 70 inches per second. By enclosing a wire of platinum within one of silver ten times thicker, and drawing down the compound wire till it be ^1^ of an inch, a wire of platinum of « _ of an inch will exist in its centre, which may be obtained apart, by dissolving the sflver away m nitric acid. This pretty experiment was first made by Dr. WoUaston. The French draw-plates are so much esteemed, that one of the best of them used to be sold in this country, during the late war, for its weight in silver. The holes are formed with a steel punch ; being made large on that side where the wire enters, and diminishing with a regular taper to the other side. In the act of drawinff, they must be well supplied with grease for the larger kinds of wire, and with wax for the smaller. WOAD (FoMerfe, Pastel, Fr. ; Waid, Germ.; Isatis tinctoria, Linn.), the glastum of the ancient Gauls and Germans, is an herbaceous plant which was formerly much cuiti rated, as affording a permanent blue dye, but it has been in modern times well nigh superseded by indigo. Pliny says, « A certain plant which resembles plantago, called glastum, is employed by the women and girls in Great Britain for dyeing their bodies all over, when they assist at certain religious ceremonies; they have then the color of Ethiopians." — Hist. Nat. cap. xxii. § 2. When the arts, which had perished with the Roman empire, were revived, in the middle ages, woad began to be generally used for dyeing blue, and became an object of most extensive cultivation in many countries of Europe. The environs of Toulouse and Miiepoix, ill Upper Languedoc, produced annually 40,000,000 pounds of the prepared woad, or pastel, of which 200,000 bales were consumed at Bordeaux. Beruni, a rich manufacturer of this drug, became surety for the payment of the ransom of his kinir Francis I., then the prisoner of Charles V. in Spain. ^ The leaves of woad are fermented in heaps, to destroy certain vegetable principles injurious to the beauty of the dye, as also to elaborate the indigoferous matter present, before they are brought into the market ; but they should be carefully watched during this process. Whenever the leaves have arrived at maturity, a point judged of very dif- ferently in different countries, they are stripped off the plant, a cropping which is repealed as ofien as they shoot, being three or four times in Germany, and eight or ten times in Italy. The leaves are dried as quickly as possible, but not so much as to become black ; and they are ground before they get quite dry. The resulting paste is laid upon a sloping pavement, with gutters for conducting the juice, which exudes into a tank ; the heap being tramped from time to lime, to promote the discharge of the juice. The woad fer- ments, swells, and cracks in many places, which fissures must be closed ; the whole being occasionally watered. The fermentation is continued for twenty or thirty days, in cold weather; and if the leaves have been gathered dry, as in Italy, for four months. When the fermented heap has become moderately dry, it is ground again, and put up in cakes of from one lo three pounds ; which are then fully dried, and packed up in bundles for the market. Many dyers subject the pastel to a second fermentation. 1,600 square toises (fathoms) of land afford in two cuttings at least 19,000 pounds of leaves, of which weight four fifths are lost in the fermentation, leaving 3,880 pounds of pastel, in loaves or cakes. When good, it has rather a yellow, or greenish-yellow, than a blue color ; it is light, and slightly humid ; it gives to paper a pale-green trace*; and improves by age, in consequence of an obscure fermentation ; for if kept four years it dyes twice as much as after two years. According to Hellot, 4 pounds of Guatimala in- digo produce the same effect as 210 pounds of the pastel of Albi. At Quins, in Pied- mont, the dyers estimate that 6 pounds of indigo are equivalent to 300 of pastel ; bnt Chaplal thinks the indigo underrated. Pastel will dye blue of itself, but it is commonly employed as a fermentative addition to the proper blue vat, as described under Indigo. Fresh woad, analyzed by Chevreul, afforded, in 100 parts, 65-4 of juice. After being steeped in water, the remaining mass yielded, on expression, 29-65 of liquid ; being in whole, 95-05 parts, leaving 4-95 of ligneous fibre. The juice, by filtration, gave 1-95 of green fecula. 100 parts of fresh woad, when dried, are reduced to 13-76 parts. Alco- hol, boiled upon dry woad, deposites, after cooling, indigo in microscopic needles ; but these cannot be separated from the vegetable albumine, which retains a greenish-gray color. WOLFRAM is the native tungsiate of iron and manganese, a mineral which occurs in primitive formations, along with the ores of tin, antimony, and lead, in the Bohemian Erzegebirge, in Cornwall, Switzerland, North America &c. It is used by chemists for obtaining tungstic acid and tungsten. 962 WOOD. ducted from the root towards the bran^hfsar^^^^^^^ tf ^Vu' ""l'^' J"^^^« ^ «>»- The ligneous fibre is the substance Xch remains Sth^^^ '^' ^'^^^^^^'^ the solvent action of ether alcohol wnt pt ^n.fto ' -i . ^^^^^ ^*^ ^^'^ subjected to considered by chemists thitd^tJrnT!' • !^ *^'^'' *"^ ^^'^^^^'^ ^^kaline leys. It S and 4 of soluble ma S t 00^ hm^itZT''"' *"" *" ^^^"""^^^ «^ ^^ P^^^^ of fibrou^ wns, the soil, and the Plant All JilS r f ^PfV^^^ ^^^ somewhat with the ^a^ of it under the exhaust^ receiti oft ""' "^"^ ''"^u ^" .^«*"''' ^^«" P^^^^^d in a bSfn mto a pulverulent mass, but eveSlv Hk^S ^T^ ^^"""^^ i""'^^ **^ cohefcnce, falls strong caustic alkaline leys 7n a W sta^^^ into oxalic acid; 'with Carbon - . . Sj,% Beech. s^;:r. : - ■ f i 'i:ll _^W of the DiST.u,AT.oN of 0»E Ponm of Wood, dried, at m Fahr. r Name of the wood. White birch - Red beech - . . Prick wood (spindle tree) Large leaved linden - Bed or scarlet oak White beech - . . Common ash Horse chestnut - - . Italian poplar Silver poplar White willow Root of the sassafras laurel Wild service tree - Basket willow - . Dogberry tree Buckthorn ... Logwood Alder . . . Juniper - . , ' White fir (deal) Common pine wood Savine tree - - . Red deal (pine) - - * Guiac wood - . . Weight of wood acid One ounce of the acid saturates of carlxinate of potash. Welphtofthe combustible oU. Weight of the charcoal. • /I ?^°l ***® ■™*^^ difference found I«i «I'47). I am inclined to think that lOiopAy of Miomfacturti, 2d edition, pp, 97, 98, 99? ^ """y ^ conwdered to be equd," 50) and of cot Of 1-50.— PW H WOOLLEN MANUFACTURE. 963 mixed with a sufficient quantity of wheat flour, made a coherent dough with water, •which formed an excellent food for pigs; apparently showing that the digestive organs of the animal could operate the same sort of change upon wood as sulphuric acid does. WOOD-PRESERVING. Mr. Bethell's invention consists in impregnaung wood throughout with oil of tar and other bituminous matters, containing creosote, and also with pyrolignite of iron, which holds more creosote in solution than any other watery menstruum. The wood is put in a close iron tank, like a high-pressure steam-boiler, which is then closed and filled with the tar oil or pyrolignite. The air is then exhausted by air- pumps, and afterward more oil or pyrolignite is forced in by hydrostatic pumps, until a pressure equal to from 100 to 150 pounds to the inch is obtained. This pressure is kept up by the frequent working of the pumps during six or seven hours, whereby the wood becomes thoroughly saturated with the tar oil, or the pyrolignite of iron, and "Will be found to weigh from 8 to 12 pounds per cube foot heavier than before. In a large tank, like one of those used on the Bristol and Exeter railway, 20 loads of timber per day can be prepared. The effect produced is that of perfectly coagulating the albumen in the sap, thus pre- ventmg its putrefaction. For wood that will be much exposed to the weather, and al- ternately wet and dry, the mere coagulation of the sap is not sufficient ; for although the albumen contained in the sap of the wood is the most liable and the first to pu- trefy, yet the ligneous fibre itself, after it has been deprived of all sap, will, when ex- posed m a warm damp situation, rot and crumble into dust. To piv^erve wood, there- fore, that will be much exposed to the weather, it is not only necessary that the sap should be coagulated, but that the fibres should be protected from moisture, which is effectually done by this process. The atmospheric action on wood thus prepared renders it tougher, and infinitely stronger. A post made of beech, or even of Scotch fir, is rendered more durable, and as strong as one made of the best oak; the bituminous mixture with which all its pores are filled acting as a cement to bind the fibres together in a close tough mass ; and the more porous the wood is, the more durable and tough it becomes, as it imbibes a greater quantity of the bituminous oil, which is proved by its increased weight. The materials which are injected preserve iron and metals from corrosion ; and an iron bolt driven into wood so saturated, remains perfectly sound and free from rust. It also resists the attack of insects ; and it has been proved by Mr. Pritchard, at Shoreham Har- bor, that the teredo navalisy or naval worm, will not touch it. Wood thus prepared for sleepers, piles, post, fencing, &c., is not at all affected by alternate exposure to wet and dry ; it requires no painting, and after it has been ex- posed to the air for some days it loses every unpleasant smell. This process has been adopted by the following eminent engineers, viz. : Mr. Robert Stephenson, Mr. Brunei, Mr. Bidder, Mr. Brathwaite, Mr. Buck, Mr. Harris, Mr. Wick- stead, Mr. Pritchard, and others ; and has been used with the greatest success on the Great Western railway, the Bristol and Exeter railway, the Manchester and Birming- ham railway, the North Eastern, the South Eastern, the Stockton and Darlington, and at Shoreham Harbor ; and lately, in consequence of the excellent appearance of the prepared sleepers, after three years' exposure to the weather, an order has been issued by Mr. Robert Stephenson, that the sleepers hereafter to be used on the London and Bir- mingham railway are to be prepared with it before being put down. The expense of preparing the wood varies from 10*. to 15*. per load, according tc situation, and the distance from the manufactories where the material is made. Mr. Bethell supplies the material at a low price from his manufactories, either at Nine Elms, Vauxhall ; Bow Common ; or Birmingham ; and parties prepare the timber themselves. For railway sleepers it is highly useful, as the commonest Scotch fir sleeper, when thus prepared, will last fo ce?ituries. Those which have been in use 3 years and up- ward, look much belter now than when first laid down, having become harder, more consolidated, and perfectly waterproof; which qualities, combined with that of per- fectly resisting the worm, render this process eminently useful for piles, and all other woodwork placed under water. Posts for gates or fencing, if prepared in this manner, may be made of Scotch fir, or the cheapest wood that can be obtained, and will not de- *^^tK^^*!^ P®^^^' ^^^^^ invariably become rotten near the earth after a few years. WOOF, 18 the same as Weft. WOOLLEN MANUFACTURE In reference to textile fabrics, sheep's wool » of two different sorts, the short and the long-stapled ; each of which requires different modes of manufacture in the preparation and spinning processes, as also in the treatment of the cloth after it is woven, to fit it for the market Each of these is, moreover dis- tinguished in commerce by the names of fleece wools and dead wools, according as 'they w mwm «i I I 964 WOOLLEN MANUFACTURE. have been shorn at the usual annual period from the living animal, or are cut from ill skin after death. The latter are comparatively harsh, weak, and incapable of imbibinff the dyemg principles, more especially if the sheep has died of some malignant distemper The annular pores, leading into the tubular cavities of the filaments, seem, in this case* to have shrunk and become obstructed. The time of year for sheep-shearing most favor- able to the quality of the wool, and the comfort of the animal, is towards' the end of June and beginning of July ;— the period when Lord Leicester holds his celebrated rural tete for that interesting purpose. The wool of the sheep has been surprisingly improved by its domestic culture. The mouflon (Ovis aries), the parent stock from which our sheep is undoubtedly derived and which is still found in a wild aate upon the mountains of Sardinia, Corsica, Barbary' Greece, and Asia Minor, has a very short and coarse fleece, more like hair than wool. When this animal is brought under the fostering care of man, the rank fibres gradually disappear; while the soft wool round their roots, little conspicuous in the wild animal, becomes singularly developed. The male most speedily undergoes this chan?e, and con- tinues ever afterwards to possess far more power in modifying the fleece of the oflspring than the female parent. The produce of a breed from a coaVse-woolled ewe and a fine- woolled ram is not of a mean quality between the two, but half-way nearer that of the fire. By coupling the female thus generated with such a male as the fonner, another improvement of one half will be obtained, affording a staple three fourths finer than that of the grandam. By proceeding inversely, the wool would be as rapidly deteriorated. It IS, therefore, a matter of the first consequence in wool husbandrj-, to exclude from the flock all coarse-fleeced rams. Long wool is the produce of a peculiar variety of sheep, and varies in the length of Its fibres from 3 to 8 inches. Such wool is not carded like cotton, but combed like flax, either by hand or appropriate machinery. Short wool is seldom longer than 3 or 4 inches; it is susceptible of carding and feltin?, by which processes the filaments become first convoluted, and then densely matted together. The shorter sorts of the combine wool are used principally for hosiery, though of late years the finer kinds have been extensively worked up into Merino and mousseline-de-laine fabrics. The longer wools of the Leicestershire breed are manufactured into hard yarns, for worsted pieces such as waistcoats, carpets, bombazines, poplins, crapes, &c. * " The wool of which good broadcloth is made should be not only shorter, but generallr speaking, finer and softer than the worsted wools, in order to fit them for the fillin*' pro- cess. Some wool-sorters and wool-staplers acquire by practice great nicety of discern- ment in judging of wools by the touch and traction of the fingers. Two years ago I made a series of observations upon different wools, and published the results Vhe filaments of the finer qualities varied in thickness from -^L_ to i _ of an inch; their •tructure is very curious, exhibiting, in a good achromatic m?croscope,\°t intervals of about jJ^of an inch, a series of serrated rings, imbricated towards each other, like the joints of Equisetum, or rather like the scaly zones of a serpent's skin. See Philosophy of Manufactures, gs. 11, 12, page 9 J, second edition. ^ » ./ There are four distinct qualities of wool upon every sheep ; the finest being upon the spme, from the neck to within 6 inches of the tail, including one third of the breadth of the back; the second covers the flanks between the thighs and the shoulders; the third clothes the neck and the rump ; and the fourth extends upon the lower part of the neck and breast down to the feet, as also upon a part of the shoulders and the thighs, to the bottom of the hmd quarter. These should be torn asunder, and sorted, immediately after the shearing. ' The harshness of wools is dependant not solely upon the breed of the animal or the clunate, but is owing to certain peculiarities in the pasture, derived from the soil. It is known, that m sheep fed upon chalky districts, wool is apt to get coarse; but in those upon a rich loamy soil, it becomes soft and silky. The ardent sun of Spain renders the fleece of the Merino breed harsher than it is in the milder climate of Saxony. Smearing sheep with a mixture of tar and butter is deemed favorable to the softness o^ the'a wool. All wool, in its natural state, contains a quantity of a peculiar potash-sGap, secreted by the animal, called m this country the yolk; which may be washed out by water alone with which It forms a sort of lather. It constitutes from 25 to 50 per cent, of the wool being most abundant m the Merino breed of sheep; and however favorable to the growth of the wool on the living animal, should be taken out soon after it is shorn, lest it injure the fibres by fermentation, and cause them to become hard and brittle. After being washed m water, somewhat more than lukewarm, the wool should be well Dressed and carefully dried. *^ * Mr. Hicks, of Huddersfield, obtained a patent some years ago for a machine for cleaning wool from burs. It consists of 4 rotary beaters, which act in succession. The wool having been opened and spread upon a feeding cloth is carried by it to the drawing rollera^ WOOLLEN MANUFACTURE. 965 and is then delivered to the action of the beater, by which it is carried along a curved grating to the feed cloth of another beater, so as to be made eventually quite clean. England grows annually about 1,000,000 packs of' wool. The quantity imported into the United Kingdom, in 1850, was 72,674,483 lbs.; in 1861, 81,063,679 lb& ; of which, 48,240,529 lbs. and 51,993,463 lbs. respectively were from British possessions. Having premised these general observations on wool, I shall now proceed to treat of its manufacture, beginning with that of wool-combing, or THE WORSTED MANUFACTURE. In this branch of business, a long stapled and firm fibre is required to form a smooth level yarn, little liable to shrink, curl, or felt in weaving and finishing the cloth. It must not be entangled by carding, but stretched in lines as parallel as possible, by a suitable system of combing, manual or mechanical. When the long wool is brought into the worsted factor)', it is first of all washed by men with soap and water, who are paid for their labor by the piece, and are each assisted by a boy, who receives the wool as it issues from between the drying squeezers, (see Bleach- ing.) The boy carries off the wool in baskets, and spreads it evenly upon the floor of the drying-room, usually an apartment over the boilers of the steam-engine, which is thus economically heated to the proper temperature. The health of the boys employed in this business is found to be not at all injured. The wool, when properly dried, is transferred to a machine called the plucker, which is always superintended by a bvy of 12 or 14 years of age, being very light work. He lays the tresses of wool pretty evenly upon the feed-apron, or table covered with an endless moving web of canvass, which, as it advances, delivers the ends of the long tufts to a pair of fluted rollers, whence it is introduced into a fanning apparatus, somewhat similar to the wUlow employed in the cotton manufacture, which see. The filaments are turned out, at the opposite end of this winnowing machine, straightened, cleaned, and ready for the combing operation. According to the old practice of the trade, and still 1541 for the finer descriptions of the long staple, according to the present practice, the wool is carded by hand. This is far more severe labor than any subservient to machinery, and is carried on in rooms rendered close and hot by the number of stoves requisite to heat the combs, and so enable them to render the fibres soft, flexible, and elastic. This is a task at which only robust men are engaged. They use three implements ; 1. a pair of combs for each person ; 2. a post, to which one of the combs can be fixed ; 3. a comb-pot,,or small stove for heating the teeth of the combs. Each comb is composed 1542 n either of two or three rows of pointed tapering steel teeth 6, fig. 1541, disposed in two or three parallel planes, each row being a little longer than the preceding. They are made fast at the roots to a wooden slock or head t, which is covered with horn, and has a handle d, fixed into it at right angles to the lines of the teeth. The spaces between these two or three planes of teeth, is about one third of an inch at their bottoms, but somewhat more at their tips. The first combing, when the fibres are most entangled, is performed with the two-row toothed combs ; the second, or finishing combing, with the three-row toothed. In the workshop a post is planted {fig. 1542), upright, for resting the combs occasionally upon, during the operation. An iron stem g, projects from it horizontally, having its end turned up, so as to pass through a hole in the handle of the comb. Near its point of insertion into the post, there is an- other staple point A, which enters into the hollow end of the handle ; which, between these two catches, is firmly secured to the post. The stove is a very simple affair, consisting merely ol a flat iron plate, heated by fire or steam, and surmounted with a similar plate, at an interval sufiicient to allow the teeth to be inserted between them at one side, which is left open, while the space between their edges, on the other sides, is closed to confine the heat, in combing the wool, the workman takes it up in tresses of about four ounces each, sprinkles it with oil, and rolls it about in his hands, to render all the filaments equally 966 WOOLLEN MANUFACTURE. r/eT; a t'L^'k^'exT^f^^^^^^^ /h'^ -'^^^ of oil, others no upwards, seizes one half of th I t ess of wooT r^h?,^!^'' '^t ^^''^."^^'^ ^^^ teeth pointed draws it 'through them, and thus re^teSly^ lei W a ^ew st;^/h7fil'i^^^^^^ ^'V^-^^^' *'^» the comb. When the comb has in thds wav collerT^ **°^« "P®" introducing the feelh oHne comb ntn ^ril "^' ^I'^ combs the wool upon the first, by «lvaL"ressfve|v horn .foTenH ,'«°'",'>y "-"tJ-S 'he lips of the tri^Zli worked wi.K ire r t«ihTclc^er.L«w ■'' ">\?">".' '"' »' "e"«h the coibs are «>*/». Thev ire nnfif f„r y. X . J^' """'''" '" P'^P ""^ '» ••'» ''»>"). are called combing heat. The comb form« » ^jUio rTf ^ jeep me whole apparatus at a proper .ee.h b?ing a.' ritu.T^^. to™e pknetf'.re the'"' '^ sh'aZof rV"' "il"','' "■« ever the wheel is dressed, the machine is made to reVre morf rapidTrbv .hiftL'?" dnving-band on another pulley; and it is beautiful to observTthe deSrv /nfl n^ ^ with which it smooths the tangled tress. When thrwooTs Ire set fn rnn? . 1 Pf^*^'«»?» l^'ltVt "•' whole leng'th of its fibres, ^^e mch Lstin^.Ln Ih i^^^^^ The following machine, patented by James IVohlP nF Woi;ro» «,« ♦ ^ • of th s cam or heart-wheel a lever rf i iT. ' "" "»e upper part of the periphery wHch lever is cor„ectTd by\ jl7 o ihe^^rke^'Bv'.he'riS.^^'J^i.™' *"j' "f WOOLLEN ^LA.NUFACTUEE. 967 1543 tiM upper or working comb or needle-points /, as it moves, performing an elliptic^ curve, which curve will be dependant upon the petition of the heart-wheel cam c, that guides it. A moveable frame g, carries a series of points hf which are to con- stitute the lower comb or frame of needles. Into these lower needles the rough uncombed wool is to be fed by hand, and to be drawn out and combed straight by the movements of the upper or working comb. As It is important, in order to prevent waste, that the ends of the wool should be first combed out, and that the needle-points should be made to penetrate the wool pro- gressively, the moveable frame g, is in the first instance placed as far back as possible ; and the action of the lever d, during the whole operation, is so directed by the varying positions of the cam-wheel, as to allow the upper comb to enter at first a very little way only into the wool ; but as the operation of combing goes on, the frame with the lower combs is made to advance gradually, and the relative positions of the revolving heart cam- wheel c, being also gradually changed, the upper or working needles are at length allowed to be drawn completely through the wool, for the purpose of combing out straight the whole length of its fibre. In order to give to the machine the necessary movements, a train of toothed wheels and pinions is mounted, mostly on studs attached to the side of the frame; which train of wheels and pinions is shown by dots in the figure, to avoid confusion. The driving power, a horse or steam-engine, is communicated by a band to a rigger on the short axle i ; which axle carries a pinion, taking into one of the wheels of the train. From this wheel the crank e, that works the lever d, is driven ; and also by gear from the same pinion, the axle of the wheel 6, carrying the eccentric or heart-wheel cam, is also actuated, but slower than the crank-axle. At the end of the axlo of the wheel 6, and cam c, a bevel pinion is afiixed, which gears into a corresponding bevel pinion on the end of the lateral shaft k. The reverse end of this shaft has a worm or endless screw /, taking into a toothed wheel m; and this last-mentioned toothed wheel gears into a rack at the under part of the frame g. It will hence be perceived, that by the movements of the train of wheels, a slow motion is given to the frame g, by which the lower needles carrying the wool are progressively ad- vanced as the operation goes on ; and also, that by the other wheels of the train, the heart-wheel cam is made to rotate, for the purpose of giving such varying directions to the stroke of the lever which slides upon its periphery, and to the working comb, as shall cause the comb to operate gradual- ly upon the wool as it is brought forward. The construction of the frames which hold the needles, and the manner of fixing them in the machine, pre- sent no features of importance ; it is therefore un- necessary to describe them farther, than to say, that the heckles are to be heated when used for combing wool. Instead of introducing the wool to be combed into the lower needles by hand, it is sometimes fed in, by means of an endless feeding- cloth, as shown in^g. 1544. This endless cloth is distended over two rollers, which are made to re- volve, for the purpose of carrying the cloth with the wool forward, by means of the endless screw and pinions. A slight variation in the machine is shown at fig. 1545, for the purpose of combing wool of long fibre, which dififers from the former only in placing the combs or needle points upon a revolving cy- linder or shaft. At the end of the axle of this shaft there is a toothed wheel, which is actuated by an ■fMMa 968 WOOLLEN MANUFACTURE. endless screw upon a lateral shaft. The axle of the cylinder on which the needle. »« .gency of the endless screw on'^^e'tS's^^^ltrr^^^ effected by th. f«r.hrd;a:i'Xme''"b"t7he"l^r.%r' '"•»«-"''"»<»" ''""' "■-" « ««»» and contains the longer fibres the^hort i. th J wh' T" ^'^""^ ""^ ^''' ^^""^ '^' ^^'^^^ « begun at the short ends; but if they are iirst parted atThe W en^/tVey^X^S? oh^^J^l'^^ilnf'lT^^^^^^ Donisthorpe and Rawson eu a paieni in Apnl, 1835, has been found to work well, and therefore merits a detailed description : — f^S' 1546, is an elevation ; ^g. 1547 an end view ; and Jig. 1548 a plan; in which «, a, is the framing ; 6, the main shaft, bear- ing a pinion which drives the wheel and shaft r, in gear with the wheel rf, on the shaft e. Upon each of the wheels c and d, there are two projections or studs /, which cause the action of the combs g, g, of which A, h, are the tables or carriages. These are ca- pable of sliding along the upper guide rails of the framing a. Through ihese carriages or tables A, A, there are openings or slits, shown by dotted lines," which act as guides to the holders i, t, of the combs g, g, rendering the holders susceptible of motion at right which turning on the axis'^o? shaft / / is cau4d toTihril' '' ''^^"^ '\^'^'^' ^> ^' arms m, mov^d by the eccentric groove n,^^^^^^^^ ^^^^ £«> ^^ ^^^ drawn inwards, by weights suspended on cords or 'train nlv V ^ t^^es A, are pulleys p, p , whereby The weights have r constant tlnf ' .' ^^"^ P'' **^^^ '^^^^^^'^n centre of The machine, as lo^ as it IsrelS^ T^^^^^^ i«'o the projecting arms ?, on the tables 0„ the shaft -^^^^^ *^^ ^^^'^""^ ^^"^ which ta'kes into the ratchet wheel " and Prooels JZTP7V\ '""''^ '^ '' ^^^^ of the shaft .. This ratchet wheel turns on an ax^ Zt tlM^^'\''l ^^V ^^^«^"tion made fast, to which the cord or bandTis secured as aho ?n ,hp'n i.^'' '^^ P"^^'' ^** y. On the shaft y, there are two other nullevs ^ t kII- t ^""7 ^' °" *^^ ^^^ made fast to the^m, and also to the end of t?e fau\ p^^^^^^ bands a, >., ated steps, against which the tables A, A are drawTn/fi » t ' f"rn>shed with graau- In proportion as these gauge-plates a^e raTsed thTnfarl th '^''''•'" '^ the machine. be able to advance to the centre of the mchinr anJ S *'*'"'^.'' ""l ^^^^^^ ^' ^"^ tolay hold of, and comb, additional lengths of the Woollv ''' '°"^'i' ^' ^' are guided up by the bars c which naL thrnn Jif • f* ^^^ gauge-plates b, the framiug o, as sho^ bj r!' ^ ^^ o^^mngs, slots, or guides, made i^ WOOLLEN MANUFACTURE. 969 To the ratchet wheel s, an inclined projection e, is made fast, which in the course of ^ rotation of the ratchet wheel, comes under the lever f, fixed to the shaft g, that turns in bearings h. To this shaft the levers i and J, are also fixed ; i serv- ing to throw out the click or catch k, from the ratchet wheel, by which the parts of the machine will be released, and restoried to positions ready for starting again. The lever j, serves to slide the drum upon the driving shaft 6, out of gear, by means of the forked hancUe l, when the machine is to be stopped, whenever it has finished commng a cer- tain quantity of wool. The combs which hold the wool have a motion upwards, in order to take the wool out of the way of the combs g, g, as these are drawn into the centre of the machine; while the holding combs descend to lay the wool among the points of the combs g, g. For obtaining this upward and downward motion, the combs m, m, are placed upon the frame n, and retained there just as the combs g, g, are upon the holders t, i. The framing n is made fast to the ba* or spindle o> which moves vertically through open- ings in the cross-head p, and the cross-framing of the machine q ; from the top of which, there is a strap passes over pulleys with a weight suspended to it ; the cross-head being supported by the two guide-rods r, fixed to the cross-framing q. It is by the guide-rods r, and the spindle o, that the frame N is made to move up and down ; while the spindle is made to rise by the studs/, as the wheels c and d come successively under the studs a, on the spin- dle o. A quantity of wool is to be placed on each of the combs g, g, and m, m, the machine being in the po- sition shown in fig. 1548. When the main shaft 6, is set in motion, it will drive by its pinion the tooth- ed wheel c, and therefrom the remaining parts of the machine. The first effect of the movement will be to raise the combs m, m, sufiiciently high to remove the wood out of the way of the combs g, g, which will be drawn towards the centre of the machine, as soon as they are re- leased by the studs/, passing the projecting arms q, on the tables A ; but the distance between the combs g, g, and the combs h, h, will depend on the height to which the gauge-plates b, have been raised. These plates are raised one step at each revolu- tion of the shaft c ; the combs g, g, will therefore be continually approaching more nearly to the as to permit the tables A, to ap- eombs m, m proach the , till the plates B, plates B, are so much raised below the lowest step or graduation, when the machine will continue to work. Notwithstanding the plates parallel surfaces against which the tables come, B, continuing to rise, there being only the combs g, g, will successively come to the same position, till the inclined projection e, on the ratchet wheel «, comes under the lever f, which will stop the machine. The wool which has been combed is then to be removed, and a fresh quantity introduced. It should be remarked, that the combs g, g, are continually moving from side to side of the machine, at the same time that they are combing out the wool. The chief object of the invention is obviously to give the above peculiar motions to the combs g, g, and m, m ; which may be applied also to combing goat- hair. For the ])urposes of the worsted manufacture, \iiool should be rendered inelastic to a considerable degree, so that its fibres may form long lines, capable of being twisted into straight level yarn. Mr. Bayliffe, of Kendal, has sought to accomplish this object, first, by introducing into the drawing machine a rapidly revolving wheel, in contact with the front drawing roller, by whose friction the filaments are heated, and at the same time deprived of their curling elasticity ; secondly, by employing a moveable regulating roller, by which the extent of surface on the periphery of the wheel that the lengths ol I i 970 WOOLLEN MANUFACTURE. Mi wool IS l^ act upon, Aay be increased or diminished at pleasure, and, consequently the effect regulated or tempered as the quahty of the wool may require; Sy,thl' em! 1549 ployment of steam in a rotatory drum, or hol- lowed wheel, in place of the wheel first de- scribed, for the purpose of heating the wool, m the process of drawing, in order to facili- tate the operation of straighteninir the fibres. These objects may be effected in several ways ; that is, the machinery may be vari- ously constructed, and still embrace the principles proposed. Fig. 1549, shows one mode: — a, is the friction wheel; 6, the front drawing roller, placed in the drawing frame in the same way as usual ; the larger wheel a, constituting the lower roller of the pair of front drawing rollers; c, and rf, are the pair of back drawing rollers, which are actuated by gear connected to the front roll- inff machi'npc fh^ rr««t ^«ii«- • ers, as in the ordinary construction of draw- r»Jn L T ' ' i. *u^"*''^ ^®"^''' *>ea«'ing upon the periphery of the lar?e wheel- f k « tension roller, which presses the fibres of the wool down upon the wheel a "^^ fJnt^'uZT^^^^' ^'''^ ^""^^^ ' «"^ ^ ^« be turned wira givrveh^ity and the ^t?n Jth r '"^ ^' ^"^^" T"'^ ^^''^'' ^^^ '^''' ^^«»Jd be, that thrfiXes of w^J consU |»vi^. dowa .0 the spindie L flier *, wh^eil T^J^ 7^,!? 1"^^^ ,r TIZ'^ ♦V 1 . , • . — '-'"*-« "1 u^i^icasru oy a racK and a winch not « the rack taking mto teeth on the periphery of the circular arrn^ " jrceived, that bv ra sin? thp n.rn„io. „.J1 .L __, '''^'^"/,?\ *^™-''-. uJt^.eans,commJ::;^t:t^^^^^^^^ tofhrsh;T{ndTf Tnot^^^ together, the long end of one of the breakine-frUe A skpVph ^f v ^ '^ •'^'T" «"t and extended by the rollers 4 pairs of roUers A b' c d ThJ fr ^^^^^^^^^^^ '« given in Jig- 1550. It consists of E,'which isTirplank^.Stable'^'Vhfs^vTr^ "^if'-^'i^K^ ^"^""^^ t-"^»> a pin, in reach of the attendant, who takis a sliver «ni1^ ^^?^\ and hung loosely over end is presented to the rollers a, whkh bein.'t mnifn %V.^ ^** u *^^ *~"=^' *"^ ^^^ is then conduct:vl through the o h^^roller L sh^wn ?^ 7h" fi*^^ T"^^ ^"' '^' ^^'^^ passed half through, the end of anoSiver is rZ^d , T^'' TJl'" i^^ '^'''''' ^^ they pass throu-h tooether- x^hel t hi* Jlli ■ ^ ^^? ."P°" ^^^ ^'^^^^ ^^^^^ fi^-st, and is 7pp'lied upon ^tSe ^ddle ift "nd^•^ h s' way tCltrt^T^'""'^!:;, ^'L^"k^ '' ^ '""'^ ing are joined into one regular and even slTv^r! " P'*^"^^ ^^^ *^^ ~°*^ The lower roller c receives its motion from thp m;n w », i. end of its axis, and an endless strap. The" ler whic'h^s Z^"^- f ,' """"?' "I"" «"• down by a heavy weisht «ii«iiPnrl<.H fm-, i. ™""J^'''<:'> « immediately over it, is borne V ui rollers p, moves with the same velocity as c, being turned 1 WOOLLEN MANUFACTURE. 971 fcy means of a small wheel upon the end of the axis of the roller c, which turns a wheel of the same size upon the axis of the roller d, by means of an intermediate wheel d, which makes both rollers turn the same way round. The first and second pairs of rollers, a and % move only one third as quick as c and D, in order to draw out the sliver between b and c to three times the length it was when pat on the planking« table, 'fhe slow motion of the roll- ers IS given by a large wheel o, fixed upon the axis of ihe roller A, and turned by the intermediate cog-wheels 6, c, and d ; the latter communicates between the rollers c and d. The pinions on the rollers c and d being only one third the size of the wheel a, c and d turn three times as fast as a, for 6, c, and d, are only intermediate wheels. The rollers b turn at the same rate as a. The upper roller e is loaded with a heavy weight, similar to the rollers a ; but the other rollers, b and d, are no further loaded than the weight of the rollers. The two pairs of rollers A, b, and c, d, are mounted in separate frames ; and that frame which contains the third and fourth pairs c, d, slides upon the cast-iron frame f, which supports the machine, in order to increase or diminish the distance between the rollers B and c. There is a screw/, by which the frame of the rollers is moved, so as to adjust the machine according to the length of the fibre of the wool. The space between b and c should be rather more than the length of the fibres of the wool. The intermediate wheels b and c, are supported upon pieces of iron, which are moveable on centres ; the centre for the piece which supports the wheel 6 is concentric with the axis of the roller A ; and the supporting piece for the wheel c is fitted on the centre of the wheel d. By moving these pieces the intermediate wheels b and c can be always kept in contact, al- though the distance between the rollers is varied at times. By means of this breaking- frame, the perpetual sliver, which is made up by planking the sliver together, is equal- ized, and drawn out three times in length, and delivered into the can g. Drawing-frame. — Three of these cans are removed to the drawing-frame, which is similar to the breaking-frame, except that there is no planking-table e. There are five sets of rollers, all fixed upon one common frame f, the breaking-frame, which we have described, being the first. As fast as the sliver comes through one set of rollers, it is received into a can, and then three of these cans are put together, and passed again through another set of rollers. In the whole, the wool must pass through the breaker and four drawing-frames before the roving is begun. The draught being usually four times at each operation of drawing, and three times in the breaking, the whole will be 3X4X4X4X4=1 768 ; but to suit different sorts of wool, the three last drawing- frames at 5 capable of making a greater draught, even to five limes, by changing the pin- ions ; acct'dingly the draught will be 3X4X5X5X5 = 1500 times. The size of the sliver is diminished by these repeated drawings, because only three slivers are put together, and they are drawn out four times ; so that, in the whole, the sliver is reduced to a fourth or a ninth of its original bulk. The breaking-frame and drawing-frame which are used when the slivers are pre- pared by the combing-machines, are differently constructed ; they have no planking- table, but receive three of the perpetual slivers of the combing-machine from as many tin cans, and draw them out from ten to twelve times. In this case, all the four rollers contribute to the operation of drawing: thus the second rollers b, move 24 times as fast as the rollers a ; the third rollers c, move 8 times as fast as a ; and the fourth rollers £, move lOi times as fast as a. In this case, the motion is given to the different rollers by means of bevelled wheels, and a horizontal axis, which extends across the ends of all the four rollers, to communicate motion from one pair of rollers to another. There are three of these systems of rollers, which are all mounted on tne same frame ; and the first one through which the wool passes, is called the breaking-frame *; ill ■ -J 972 WOOLLEN MANUFACTURE. wh.Vhh * 'Jiffer from the others, which are called drawing-frames. The slivcn which have passed through one system of rollers, are collected four or fiv; together an^ £1 w^T'^ .'^^ /Irawmg-rollers. In all, the sliiers pass through tl^ee drawings' and bvl^ifn^^!'^'^'^^"? ""^ ^^^ '^^^^" ^^ fi'^'^^e^* a pound weight is talien, and is measured by means ol a cylmder, in order to ascertain if the drawing has been properly c#nducted^ 1^ mendld't^^h.' "°' nr '• -^^ ^'T^ ^'""^''^^ *^^«^^i«^ '^ ^h« «i'« oTworsted wS IS intended to be spun, the pinions of some of the drawing-frames are changed to maW^ shver become so small, that it would break with the slightest foreland U is th«efo« wi«''bntffl^ir„T-^T!;'' !%f "■"'='' "''^"',<' '»»i"S-f™me, that a short deseriptioB fV.™. t .V ' * '«'.'''"'>'. ^"hich are 'aken ofl' from the spindles of the rovine^ rcom,\7^'- ""''v''" l."'^' ^""' "' ''"* "P"" *''««'"*. »■»' Ihe Ling whieh proceed from them is eonJucted between the rollers. The back pair turns rSund slowly Se middle pair turns about twice for once of the back rolle s; and the front paTm'akeS ernr„":h^hTr■^^u^"r " "" ""^ '"™ " '"* "'"' ™""' --"'"^ '» "•^^»«- «" r.J'?^-.''!i"'^^^^ T^' .'■^''''^''^ ''^''y ^"'*^^'y ^'" t*»e spinning-frame, in order to give the ^^TlnP^r^^^^^^^ to the worsted The hardest twisted worsted Is c2d tammy weight fhP w ? .^^^ J'^^,l^^^« ^^orsted IS such as to be 20 or 24 hanks to the pound tTe wo'rJted for finl ^.^ •' ^^ '?•"? ^" ?^'^ ^"*^^ ^^ ^^"S^*'' ^he least twist is given to fromTt ft / ^ hosiery', which is from 18 to 24 hanks to the pound. The twist is S^ilkvs unon r ^ H?'^' 7t^ If ^'"t °^, ^^^^' '^ ^■^-""'^^^'^ »>y ^^e size of the wSls or front ronilcV ♦t'^K^'.^^l^y, ^^^ wheel- work which communicates the motion to the Iront rollers from the band-wheel, which turns the spindles. Won^ "fediess to enter more minutely into the description of the spinning machinery ^nder'ci™ " m/v"'' construction, invented by Sir Richard Arkwright, fu^ll^es rS fwpfn ,^°™^.M^^^^^^CTURE, is equally applicable to worsted. The difference be- s canable nTV' "^'-^^ ^" '^f distance between the rollers, which, in the worsted-^rame fihrorr fu ^^'?" increased or diminished at pleasure, according to the length of the cotton ' ^""^ '^' '^"'"^^' ""' "'^'""'^°" ^^ '^^ '«^^"S is for greater than in the » wT"~'^^^,*'°^^'"^ ""/ !^^ spinning-frame are placed in a row upon wires before a long horizontal reel, and the threads from 20 bobbins are wound off togelhe^ The reel is exactly a yard in circumference, and when it has wound off 80 turns, it rinos a nffu^ ?^K°" ^5 '\^ '^f '' *^^" «^«PP^^' ««d ^ thread is passed round the 80 ?u'rns Jartts wotd'off w^'?^- '? "'^'- '^^/-•-g - then 'continued till anothlr 80 yaras is wound off, which is also separated by interweaving the same thread • each of these separate parcels is called a ley, and when 7 such leys are reeled, it is caled a hank which contains 560 yards. When this quantity is reeled off, the ends of the hS^ bread are tied together, to bind each hank fast, and one of the rails of the reel is struck to loosen the hanks, and they are drawn off at the end of the reel. The'e hanks are ZTJa? "r ^ ^""'5' «nd twisted up hard by a stick ; then doubled, and he two parts X 1 'f '^"" 'IT\' ^ ^"" ^r^^'' ^" '^''' ^^^^^' '^' ^«»k« are^veighed by a smSI index machine, which denotes what number of the hanks will weigh a pound and ther woVT^K ^''''f'}^'y into different parcels. It is by this means tlfat thrnumber of the worsted IS asceitained as the denomination for its fineness : thus No. 24 means that 24 hanks, each containing 560 yards, will weigh a pound, and so on. ' comaiL fiSr « ^h'"" • 't ^!f'r'".ln''T '^^'' "'^ ^"' ^^"«"' ^'^^"^^ the hank of cotton ^me Pnf,t ' tK ' '"*f ^"^ ""^ ^^ ' **"' '"^ '^"^^ P'^^^^ the worsted hank is made of the same length as the cotton. . n^?, ^f"^ "P i^^ worsted for market, the proper number of hanks is collected to make a pound, according to the number which has been ascertained ; these are weighed as a fn^nfiu l°""5f »^«« «^ the sorting, then tied up in bundles of one pound each, and IZJ ,-^ ^'""u'?^ are again tied together. Then 60 such bundles are packed up in • sheet, making a bale of 240 pounds, ready for market. «* up m • not^f r.!/'*''''T*' °-^'^''''^ '^^. -^"i: '^' ''^''^^ manufaciure.-Short wool resembles cotton thl . ; "" the structure of its filaments, and is cleaned by the willy, as cotton is by ^liZ'l7'- "" '"^ '"'^If.^P }^^ ""f ^i'^ ^""'" °^ ^^^ wool-stapler, and cleans it from accidental impurities. Sheep's wool for working into coarse goodJ, must be passed re- iv ^> j »» nl WOOLLEN MANUFACTURE. 973 peatedly through this machine, both before and af\er it is dyed ; the second last time for the purpose of blending the different sorts together, and the last for imbuing the fibres intimately with oil. The oiled wool is next subjected to a first carding operation called tcribblingy whereby it is converted into a broad thin fleece or lap, as cotton is by the breaker-cards of a cotton mill. The woollen lap is then worked by the cards proper, which deliver it in a narrow band or sliver. By this process the wool expands greatly in all its dimensions ; while the broken or short filaments get entangled by crossing in every possible direction, which prepares them for the fulling operation. See Carding, under Cotton Manufacture. The slvbbing machine, or billy, reduces the separate rolls of cardings into a continuous slightly twisted spongy cord, which is sometimes called a roving. Fig. 1551 is a per- spective representation of the slubbing machine in most common use. A, a, is the wooden frame ; within which is the moveable carriage d, d, which runs upon the lower side rails at a, o, on friction wheels at 1, 2, to make it move easily backwards and for- wards from one end of the frame to the other. The carriage contains a series of steel spindles, marked 3, 3, which receive rapid rotation from a long tin drum f, by means of a series of cords passing round the pulley or whorl of each spindle. This drum, 6 inches in diameter, is covered with paper, and extends across the whole breadth of the carriage. The spindles are set nearly upright in a frame, and about 4 inches apart ; their under ends being pointed conically, turn in brass sockets called steps, and are retained in their position by a small brass collet, which embraces each spindle at about the middle of its length. The upper half of each spindle projects above the top of the frame. The drum revolves horizontally before the spindles, having its axis a little below the line of the whorls; and receives* motion, by a pulley at one of its ends, from an endless band which passes round a wheel e, like the large domestic wheel formerly used in spinning wool by hand, and of similar dimensions. This wheel is placed upon the outside of the main frame of the machine, and has its shafts supported by upright standards upon the carriage d. It is turned by the spinner placed at q, with his right hand applied to a winch R, which gives motion to the drum, and thereby causes the spindles to revolve with great velocity. Each spindle receives a soft cylinder or carding of wool, which comes through beneath ft wooden roller c, c, at the one end of the frame. This is the billy roller, so much talked of in the controversies between the operatives and masters in the cotton factories, as an instrument of cruel punishment to children, though no such machine has been used in cotton mills for half a century at least. These woollen rolls proceed to the series of spindles, standing in the carriage, in nearly a horizontal plane. By the alternate advance and retreat of the carriage upon its railway, the spindles are made to approach to, and recede from, the roller c, with the effect of drawing out a given length of the soft cord, with any desired degree of twist, in the following manner : — The carding rolls are laid down straight, side by side, upon the endless cloth. Strained in an inclined direction between two rollers, one of which is seen at b, and thf i 974 WOOLLEN MANUFACTURE. 'i! ^ •I I' '\ ' 1 mi Other lies behind c. One carding is allotted to » mm,!!- ♦!.*., one machine being from 50 to 100. T^ roller co?^Atwn^^ "'^*^^' ""^ ~*^'»> Its weight upon the cardings, while they move onwards ove 7^J T''^\ ^f"^^5^ ^^^ running out of the spindle ^cirriage. llZZiZt^LZX^^ horizontal wooden rail or bar g, with another bpnpaih t lu Ji ?"^'^' ^^^'"^ '^ » carding is conducted through belween Zse two W^.f^ ^"T '^^ ^''''^^' ^he raised to let any aliquot portior^f the rSf pals fe^^^^^^^^^^ k^'''' '"' **"^"^ down, it pinches the spongy carding fast -whence thkm..^o- ?' *^n 'I *^»'" ^«« It is in fact the clove, originally used bv Har^rervP. in h ^*"'''" " ^*"^ ^^'^ <^^«sp. upper rail ojs guided between "Hders,'ln^^^ from the inclined plane b,c There^h a s^/rS^^^^^^ ""^J"^' ^""^'"^^ ^^"^^^ of the clasp G, and hiude^ i from falHn^ tm If '•'"^'"w^ ^^^' ^""'^ «^ ^^« "PP^^ ^^ tance, and has therebralTowed f"m " ?o g ^n Je^^^^^^^^^^ **f- '"'"^"^ '^ ^ ^«^^^^^" <"«" stop upon the carriage then comesTaainst the catch n ^ 'f.l'"^' '-^ **^ '^•^^" ««^- ^ upper rail to fall and pincrthrcardfnrwhil fht ^ ^ withdraws it ; thus allowing the out or stretches that po'rUon of the'r^H ^.JhTcUs b'e w^T^e^rasrandThe^rHf ^ '^'^"» But during this time the wheel has been turned to keen tht .n nHi , -^'"^^^ P*""*^** eating the proper degree of twist to thp V^rHinL ;„ ^ the spindles revolving, communi- prevent them from breaking. "^' '" Proportion to their extension, so as to It might be imagined that the slubbing cords would hp •«♦ t^ i j i^ . but as they proceed in a somewhat inclined dTrect'oi to the' cl^^^^ ^^' ^P^"*^!"' twisting motion, continually slipping over the noints of thi ?'• V ^^^'P "^'"^^^ * wound upon them. Whenever the onpnitivp or Ti ,kk I ^. ^P'^^^^^^, without getting to the roWngs, he set^ a^urwindinT^erunon^^^^^^^ '^'i ^''''^ * "^"^ ^'^''' ""^ ^^'^^ which purpose he presses dowT^hefaller-wire'^S^^h hisleft'h '"i" ' """'"l^ ^^«P^' ^°' from the points of {he spindles, and placTit onnositTto thlill^-^^!'^' '''. ^' S ^^^' '' ^*^^" the spindles revolve, whUe he pushes in the carH j! ^^^"^^^^^^^'e part. He next makes upon the spindle into a conical corThewireTre^u^^^^^ V '"" V^Vl"l>Wng series of slubbings at once and receivpritlmnnc^ , V^® winding-on of the whole from the horizonral rail f which tur^^^^^ ^""^? °^ depression for this purpose standards, which rise f om 7he carrlg^ B^vTurnii". tV '""^-l' '" ^'""'f'' fixed on the may be raised or lowered in an v decree THp^^kk^ ^^-^ '*u ""^ '^^ P^^^^s, the wire 8 to draw the carriagrou^ but ^n rfturnin- ^t hl^ ' seizes the rail 4 in his left hand, lime that he pushes the cirrt^befS^ ''"'""" '" faller-wire, at the same ^^''^^:^^ pulleys, as shown in^ri^re, rhas a heaU w^^^^^ roller and after passing over weight at the other, to kefp i tnsta„tfy ex^te^ed^U^^^^^ ^"^^' turn the rollers with their endless clot^ round In suVadirfction^^^^^ r"^' !S the rovmgs, without puttin*' anv strain nnnn tLl v a»rection as to bring forward pushed hom'e, the "ar|er wc%h74ts Lun^^^ Z^" ^^?' ^^^ ^^^^^^^ « the greater weight turns iTe ro lle'r anradvan?p; ?h J*,'" ^^^ '^"'"'^^^ ^^ *^^«^^ <>««> carding at the skme rate Tt^e carriat runs o^^^^^ T""' ^ *^ '" '^^"^^^ ^he livered, a knot in the roprarrives at a^xed Inn Lv ». i"^" ^^^ P'^'P" ^"^"^^1^ »s de- further'; while at the same Sn the roller stuU^lhe'L^^^^^^^ "°?T'' * V° '"""^ "^^ G, of the clasp to fall, and pinch the Sn^ fas? the wW? t' VI' *"r' ^^^ ^^^^^ '"^ makes the spindles revolve • and tL rSal k '• ^ ,^ ^' ^'"^ *^^" ^et in motion, the slubbings whiLuXtW influence r^^^^ simultaneously dmwn out, extendi operative m'ust take care to pu h in "re cLr7a^^^^^^^ tn?"^'",? "^u'^f slubbings, the rates that the spindles will not lake up fa fer^than thl p. ™ ^^' ""^'^^ ™""^ *** ^"^^ or he would injure the slubbings Thp\Ll!v ? carnage moves on its railway, bring the carding^Lm the cardln«^i Je toX^^^^ '^^"''^^ 'u^ attendance of a child, to joinlhe ends of 'the ?r^sh Les care^^^^^^ ^t^ CendsTfXoth p'^'^'f '^^'^'-^^^-^ to roller. Slubbings intended for war^^arn must be mor ° -c^iiTJ^ ^T" "/^" ^^« but each must receive a degree of "r^,^,„ rekt"ve to tZLlTH '*'^" '^^'S^"'' ""^^'^ intended to be made. In general however no mnl^ ^T^l^^ of wool and of the cloth I may here remark, that various machines have been constracted of late year, fr. ■^ ^^ WOOLLEN MANUFACTURE. 975 making continuous card-ends, and slubbings, in imitation of the carding and roving of the Cotton Manufacture ; to which article I therefore refer my readers. The wool slubbings are now spun into yarn, in many factories, by means of the mule. Indeed, I have seen in France the finest yarn, for the mousseline-de'laine fabrics, beautifully spun upon the self-actor mule of Sharp and Roberts.* rew/mng.— When the cloth is returned from the fulling-mill (which see), it is stretched upon the tenter-frame, and left in the open air till dry. In the woollen manufacture, as the cloth suffers, by the operation of the fulling-miU, a •hrinkage of its breadth to well nigh one half, it must at first be woven of neadv double Its intended width when finished. Superfine six-quarter broad cloths must therefore be . turned out of the loom twelve quarters wide. Burling is the name of a process, in which the dried cloth is examined minutely in every part, freed from knots or uneven threads, and repaired by sewing any little rents, or in- serting sound yarns in the place of defective ones. Teasling.— The object of this operation is to raise up the loose filaments of the woollen yarn into a nap upon one of the surfaces of the cloth, by scratching it either with thistle-heads, called teasels, or with teasling-cards or brushes, made of wire The natural teasels are the balls which contain the seeds of the plant called DipsaaufuU lorum ; the scales which form the balls project on all sides, and end in sharp elitic points, that turn downwards like hooks. In teasling by hand, a number of these baUs are put into a small wooden frame, having crossed handles, eight or ten inches long : and when thus filled, form an implement not unlike a curry-comb, which is used by two men, who seize the teasel-frame by the handles, and scrub the face of the cloth hung m a vertical position from two horizontal rails, made fast to the ceiling of the workshop. First, they wet the cloth, and work three times over, by strokes in the direction of the warp, and next of that of the weft, so as to raise all the loose fibres from the felt, and to prepare it for shearing. In large manufactories, this dressing operation is performed by a machine called a gig-mill, which originally con- sisted, and in most places still consists, of a cylinder bristled all over with the thistle- kaads, and made to revolve rapidly while the cloth is drawn over it in a variety of directions. If the thistle be drawn in the line of the warp, the points act more eflS- caciously upon the weft, being perpendicular to its softer spun yarns. Inventors who have tried to give the points a circular or oblique action between the warp and the weft, proceed apparently upon a false principle, as if the cloth were like a plate of metal, whose substance could be pushed in any direction. Teasling really consists in drawing out one end of the filaments, and leaving the body of them entangled in the cloth ; and it should seize and pull them perpendicularly to their length, because in Uiis way It acts upon the ends, which being least implicated, may be most readily disengaged. ' When the hooks of the thistles become clogged with flocks of wool, they must be taken out of the frame or cylinder, and cleaned by children with a small comb. Moisture moreover, softens their points, and impairs their teasling powers; an effect which needs to be counterbalanced, by taking them out, and drying them from time to time Many contrivances have, therefore, been proposed in which metallic teasels of an unchan'^eable na- ture, mounted m rotatory machines, driven by power, have been substituted for the vege- table, which being required in prodigious quantities, becomes sometimes excessively scarce and dear in the clothing districts. In 1818, several schemes of that kind were patented in France, of which those of M. Arnold-Merick, and of MM. Taurin freres, of Elbceuf, are described in the 16th volume of Brevets dUnvention expires. Mr. Daniell, cloth manikc- turer in Wills, renewed this invention under another form, by making his rotatory cards with two kinds of metallic wires, of unequal length ; the one set, long, thin, and delicate representing the points of the thistle; the other, shorter, stiffer, and blunter, being in- tended to stay the cloth, and to hinder the former from entering too far into it. But none ot these processes have succeeded in discarding the natural teasel from the most eminent manufactories. *««.» The French government purchased, in 1807, the patent of Douglas, an English me- chanist, who had, in 1802, imported into France the best system of gig-mills then used in the west of England. A working set of his machines having been placed in the Con^ ttrvatotre deserts, for public inspection, they were soon introduced into most of the l?rench establishments, so as generally to supersede teasling (lainage) by hand. A de- scnption of them was published in the third volume of the Brevets d'Inveniion. The follow- ing IS an outline of some subsequent improvements : 1. As it was imagined that the seesaw action of the hand operative was in some re- spects more effectual than the uniform rotation of a gig-mill, this was attempted to b« imitated by an alternating movement. ^ U9 thii admirabla machiM fully dmribed uid deUneated in my Ctttom Manu/aeture of Grtat 976 WOOLLEN MANUFACTURE. i !; Xi i m ♦»f: ^^^"^ conceived that the seesaw motion was not essential, but that it was advan- apous to make the teasels or cards act in a rectilinear direction, ks in wo k nX haT* his acfon was attempted by placing the two ends of the teasel-frame in grooves formed Hke hW rf/rf' V^V^"; ^^^«^' should act on the cloth only when it caCInto tLT fectU. lhrcons[rucli^n. ^'"'' "-^^"^^-maker, of Manchester, obtained a patent, in 1I32, for ^J:J\'^^^ supposed that the teasels should not act perpendicularly to the weft but ed n i/lO^T^"''^ rT" J!^'/"^^ '!■ '^^ '^''^' ^'- ^^ '^^^ee, of Gloucester pa'tent! ed, m 1830, a scheme of this kind, m which the teasels are mounted upon two endless chains which traverse from the middle of the web to the selvase or list, oneTrthe rl^ht Ind Z the effect 'ol" ''"t' ^'^^^ ^*^^.-^'°^' \''''' ^^'^'^ ^^^ ^^^^ -^" such a v^lodty^ antlefoS^^^^ action, dividing into two equal parts the reS and ft Tr t ■ ^S'^rl ^"^ '""^l^ y Y"'- ^^'^^ P^^^"^ machines of Mr! George Old- InthTfi^/lVtV f''^'''^^^^^ inl832-all proceed upon this prhiciple i?n h ^'"V ^^^^f^ ^'^ mounted upon discs made to turn flat upon the surface of the ?ie cloth wh- r- '*^' "'' 'T^""^ ^''''' ^'' ^'''''^ ^y corkscrew spiral springs against sprinis 'aLTn thVth'T''^ k^ ^\'^^''''' «"^hi«"> «1^« Pressed igainst' the discs by turn lot fn 1 L^ third machine, the revolving discs have a larger diameter, and theV lurn, not m a horizontal, but a vertical plane bv^flat^h.'rH ^"r'''^ '^V^ '"^"f'^ ^' beneficial to support the reverse side of the cloth CUseld Kpi^lf'''' '''^''' l''\"^. "P^"^ '^^ ^'^^^ '"^''^ ^^^^«' or teasels. Mr. Joseph hind ? mJ : r^ f^''^'^ '''S *=^"'^ "P°" ^™°°^^ ^^^^1 stones, teasels them by ?he bacLMhT;i.Ph "''f^T'^-^"^ ^"""^ "''^^^"^'^ ^ P*^«"t' i*^ ^829, for supporting acLn 6 Ph J^ with elastic surfaces, while the part was exposed to the teaslini tTons oV Mr Spv I M i «J?« l>^^",J"Parted to the teasels, in the three patent inven: u.Pn,l to ci V L^': ^' F; ^^"'^"' ^"^ ^'- ^- Atkinson. 7. It has been thought usefu to separate the teasel-frames upon the drum of the gig-mill, by simple rollers or aLSin'/'^'^ with steam, in order to obtain the combined klct of caleSng and teaslmg. Mr. J. C. Darnell, Mr. G. Haden, and Mr. J. Rayner, have obtained for mlin"' t^-lT"' '^t '"^^ ^^J^' ^' ^'^'^^^ ^^^"^^^ schemes'have been mount^S on t^fsame ma?h;^e."°' "'°" " '""" '''^'' ^^'^" '^''^' "^ ^"^'^ ^^ "^«""^ *^° ^^^ to^rPVPn^th/r^^^^.-' ^"""r"/?? ^ ^^'"^ excellent method of stretching the cloth, so as ,Wn J'^ n^ Mr. Collier, of Pans, obtained a patent, in 1830, for a greitly do?Mer« ^V^h^f n"^^" Douglas's plan, which is now much esteemed by the French dothiers. The following figures and description exhibit one of the latest and best teasline ?pW "'• 1.^- V^f 'Vt"'^"". ^^^- ^"^^^^ ^"'^ C«" «f I^o"viers, and is nov^dofn ' ex! cellent work ,n that celebrated seat of the cloth manufacture. ° its othlr^fmlll!?'"''"' r^\'^°''"? "?** ^"'l"^'"^' ^^y^"d thickness, at the expense of n breadth TkT?' '' ^'"'w'' •"? I,'''/'^^ '"^"'"^ ^^^^^^ ""'^ ^^^^d in length, and one half l^H f. t ' »' J surface is diminished to one third of its size as it comes out of the loom- Sv tea^lint' tZT"' '^^''^'^^^^^^^^old in thickness. As the filaments drawn forth with d ffpfpn, h1 ^'^ TT^^ ^'""'^'' '^'y '""^^ ^ '^^'^ to make them level, and with diflTerent degrees of closeness, according to the quality of th- stuff and the an pearance it is desired to have. But, in general, a single opemt on of each kind is Z sufficien ; whence, after having passed the cloth once through the 4-mill and on^ h'irthVtf rnrrnt^suff^'"^""^' '^ I' "^'^ ^^^'^^^^ ^ seco\d'?e"^^g,lrp« of these processes as nftp„' f •' ? ''"T '^"^''"f' ?^^"'' ^^ *^« ^^^^^"^te fepetition aoDearance S nf ih *' f-^^""^** P'^'P^'"' ^^^ ^^^^^ ^"^"y acquires its wished-foi beTconducted he cloth t "P^^^^'°"f ^'^ ^^^^ ^^^li^^te, especially the first ; and if the, ^^S^l^t^t:^^:^^ ''-'-' ^-^-=-^ --^ species^f furl^hfct upon a wrought-iron shaft k, which hLj .titll^^^t'^nd' (M T^3) exterloTto'^ frame, the usual riggers, or fast and loose oullev /-j*' /* wKf:*.h -^^ exterior to the machine by a band from the main shaft of the mil ^'£itf ri^h end'wifr„ t? r^ '^* —■v WOOLLEN MANUFACTURE. 977 II 578 WOOLLEN MANUFACl (JRE. other two, towards its extremities. Their sTzemavh2 •^', ""f '^i^ ?^ ^^^ ^^^^ r, and the 1552. After havingset them so hat alUhefr sSs or'r^^^^^^^ "^' ^'""^ \"^P^^^'^" ^^fiS' Sides H, are made fast to the 16 portions of theTeHnh/ '^'^''Jl^^^Pond exactly, the 16 wheels. These sides are made of sheet^ronr.irv.^^^^^^ '^^''^J' correspond in the three ed o/f at the end, fig. 1553, and^ach J^h^m IIp;"; \f "f ^"""'•^^- ^•''>^2, butround! three bolts h, The%lastic^art 7tL plate^ron a^^^^^^^^ n^-"t ^^^^''' '^'^' ^^^^^^ »> i6 frames bearing the teasels which are to J., ^ ^^{"^^^ed, with proper precaution^ follows :_Each has the shape of a rectan^'^^ .^hese are fitted in as but their breadth only We enouoh in "n^'. • * ^^"^'^ ^^"«* to that of the drum, thus making two rows of Sel teasels thr^^^^^^^ th stle-heads set end to end in M 1552 ) A portion of ie Cnt is reJe""^^^^^^^ il"/^^' <«-« the contouJ a..nst Which the tops of the teasels^^est, IStl :::/L:fL^J^-^^^ ' ^ ' '-^^^ Ef ' ''^" ^'. '^'^ throughout its whole i hfi ' '^^'^^'i''^ ^^^ tails of the teasels, Avhich are seated and compressed in it. There are, moreover, cross-bars t, which serve to ^^____^^ maintain the sides of the frame i, at an inva- rBWnmTT- "^^^ d'stance, and to form short compart- ends are fortified by stronger bars k k ^"fJ^^'f^r ^f.^Pi"f tjie thistles compact. The between the ribs. The distance of th/iwir r^u^T'"" ^^^' to fasten the frames other .ee fil 1^ ^^Sl :^^-t^^^^ -n - ^cli^d pl.e of | 1555 r=,^ rest upon the flat parts of the ribs themselves. T^i fhTl ?"A'''"'^*^' '^ '' "^^^°°«' that if the ends of Bnf ^h X ^^^^OPP^^ the frame will be made fasU But ihey need not be fixed in a permanent man- ner, because they must be frequently removed , f"d replaced They are fastened by the clainp K i^^'-' .^f ^' ^?^)' ^^hich is shut at the one end and r i^ ^=^ ^^ furnished at the other with a spring, which can be V J opened or shut at pleasure. 2 and 4, in fifr. 1553 the clamp,^g,. 1555, 1556 The birTthe rSffl'"^ -^i^"'^^* ''>'^^«^^ theplaceof X?i& ' ''^P^ is'th^nttirn ?r tt^eAthtl^Tam?^ ^^^"^^' '' '^^^^"^ be requisiel^these successive drcu^^^ the other as many times as sh^' under certain condit?oL.""lT"rdeTo"L^Wperl7? ailed' tt'must V ^'^ ^^"^^^? tension throughout its whole breadth durin "'f V^^u^ ^\ ^^'''*' more or less close contact with thp Hr,,r« « "« traverse ; it must be brought into the stage of the oyrTtlot ;" 1 JfJsTintTJa^ "'^^T '' ^'^ ^^^^''-'^^^ embracing a ereater or smaller nnrtl!In .r -.1 * /angent to the surface, and somet mes speed, deJendanruLn the veToc^t^^^^^^^^ '''"'°7' 'f T'^ ^''^^^^ ^'th a determinate result: themachiTi?self mus^mlk/th^^^^^ and calculated so as to produce the best the other. '"'''' "^^^^ ^^^ "'"^ P^^^ alternately from one winding beam to collet /', and top collet T, in th? proL^o h'e str c'herT'ut'n ''tht' "^^'t shaft are mounted— . a bevel whppl r'. 9 on „™ i. . • . ' ^P"" ""' "Pnght 3. a lower bevel pinionV wi uTts hn« »' Ti l"^^' .''T' .P'"'"" "' ''"'' »" •>»«' «'; L, and con,mu„ica!e MoT; tie moveme„rif rl atinrt^'V"?.'-' " ^"^^ "P"" ""' '""« /.with which it is in war • LttheT?n^nV,I.vi, •'"'''' '« ««ives from the pkia drum, ,».rticipates in t^e rotation whicr.h{s "hi^rZ^vTf """.". 'heshaftFirf^ rrati';rs^fi.trr^j,{; -: «r te^^^^^^ ^. i. mav be tu'^ned -J^^^^^^l^iZ^ f^ ^ ^teS^S^' ■RHMVir^ WOOLLEN MANUFACTURE. 979 its bottom, and which may be rendered active or not, at pleasure ; these curved teeth, and their intervals, correspond to similar teeth and intervals upon the top of the boss M', which is dependent, by feathered indentations, upon the rotation of l, though it cmn slide freely up and down upon it. When it is raised, therefore, it comes into gear with M. The pinion k, and its boss, have a similar mode of being thrown into and out of gear with each other. The bosses m' and n', ought always to be moved simultaneously, is orler to throw one of them into gear, and the other out of gear. The shaft l serves to put the cloth in motion, by means of the bevel wheels p" and q", upon the ends of the beams p, q, which take into the pinions m and n. The mechanism destined to stretch the cloth is placed at the other end of the machine, where the shafts of the beams p, q, are prolonged beyond the frame, and bear at their extremities p' and q', armed each with a brake. The beam p {fig. 1552), turns in an opposite direction to the drum ; consequently ihe cloth is wound upon p, and unwound from q. If, at the same time as this is going on, the handle r', of the brake- shaft, be turned so as to clasp the brake of the pulley Q',and release that of the pulley p , it is obvious that a greater or smaller resistance will be occasioned in the beam q, and the cloth which pulls it in unwinding, will be able to make it turn only when it has acquired the requisite tension; hence it will be necessary, m order to increase or diminish the tension, to turn the handle r' a little more or a little less in the direction which clasps the brake of the pulley q' ; and as the brake acts in a very equable manner, a very equable tension will take place all the time that the cloth takes to pass. Besides, should the diminution of the diameter of the beam Q, render the tension less eflScacious in any considerable degree, the brake would need to be undamped a very little, to re- store the primitive tension. ^ When the cloth is to be returned from the beam p, to the beam q, z must be lowered, to put the shaft l out of gear above, and in gear below ; then the cloth-beam q, being driven by that vertical shaft, it will turn in the same direction as the drum, and will wind the cloth round its surface. In order that it may do so, with a suitable tension, the pulley q' must be left free, by clasping the brake of the pulley p', so as to oppose an adequate resistance. The cloth is brought into more or less close contact with the drum as follows : — There is for this purpose a wooden roller t, against which it presses in passing from the one winding beam to the other, and which may have its position changed relatively to the drum. It is obvious, for example, that in departing from the position represented in fig, 1552, where the cloth is nearly a tangent to the drum, if the roller t' be raised, the cloth will cease to touch it ; and if it be lowered, the cloth will, on the contrary, embrace the drum over a greater or less portion of its periphery. For it to produce these eflTects, the roller is borne at each end, by iron gudgeons, upon the heads of an arched rack t" {fig. 1552), where it is held merely by pins. These racks have the same curvature as the circle of the frame, against which they are adjusted by two bolts ; and by means of slits, which these bolls traverse, they may be slidden upwards or down- wards, and consequently raise or depress the roller t. But to graduate the movements, and to render them equal in the two racks, there is a shaft u, supported by the uprights of the frame, and which carries, at each end, pinions u', u", which work into the two racks t', t" ; this shaft is extended in front of the frame, upon the side of the head of the machine {fig. 1553), and there it carries a ratchet wheel tt,and a handle u'. The work- man, therefore, requires merely to lay hold of the handle, and turn it in the direction of the ratchet wheel, to raise the racks, and the roller t, which they carry ; or to lift the click or catch, and turn the handle in the opposite direction, when he wishes to lower the roller, so as to apply the cloth to a larger portion of the drum. CLOTH CROPPING. Of machines for cropping or shearing woollen cloths, those of Lewis and Davis have been very generally used. Fig. 1557 is an end view, and^g. 1558 is a side view, of Lewis's machine for shearing cloth from list to list. Fig 1559 is an end view of the carriage, with the rotatory cutter de- tached from the frame of the machine, and upon a larger scale ; a, is a cylinder of metal, on which is fixed a triangular steel wire ; this wire is previously bent round the cylinder in the form of a screw, as represented at a, a, in fig. 1557, and, being hardened, is intended 10 constitute one edge of the shear or cutter. The axis of the cylindrical cutter a, turns in the frame 6, which, having proper ad- justments, is mounted upon pivots c, in the standard of the travelling carriage rf, d ; and «, is the fixed or ledger blade, attached to a bar /, which constitutes the other edge of the cutter; that is, the stationary blade, against which the edges of the rotatory cutter act ; / and g, are flat springs, intended to keep the cloth (shown by dots) up against the cutting edges. The form of these flat springs /, g, is shown at figs, 1560 and 1561, 84 980 WOOLLEN MANUFACTURE. as consisting of pJates of thin metal cut into narrow slips I fig. 1560) or Derfor«t«I with long holes {fig, 1561.) Their object is to support the ciofh, which Ts intendSlu pass between them, and operate as a spring bed, bearing the surface of the cloth against the cutters, so that its pile or nap may be cropped off or shorn as the carriage d is drawn along the top rails of the standard or frame of the machine fc, A, by means of cords. The piece of cloth to be shorn, is wound upon the beam fr, and its fnd is then con- ducted through the machine, between the flat springs / and g f is shown in fig. 1559), to the other beam /, and is .'. ~ —^ _i__». then made fast; the sides or lists of ihe cloth being held and stretched by 'small hooks, called habiting hooks. The cloth being thus placed in the machine, and drawn tight, is held dis- J vl560 ^^— >^ 1559 1561 ( i tended by means of ratchets on the ends of the beams k and /, and palls. In ccfmmenc- ing the operation of shearing, the carriage d, must be brought back, as in fig. 1559, so that the cutters shallbe close to the list ; the frame of the cutters is raised up on its pivots as it recedes, in order to keep the cloth from injury, but is low- ered again previously to being put in action. A band or winch is applied to the rigger or pul- ley m, which, by means of an endless cord passed round the pulley n, at the reverse end of the axle of m, and round the other pulleys o and p, and the small pulley g, on the axle of the cylindrical cutter, gives the cylindrical cutter a very rapid rotatory motion; at the same time a worm, or endless screw, on the axle of m and n, taking into the teeth of the large wheel r, causes that wheel to revolve, and a small drum *, upon its axle, to coil up the cord, by which the carriage d, with the cutters o and e, and the spring bed / and g, are slowly, but progressively, made to advance, and to carry the cutters over the face of the cloth, from list to list ; the rapid rotation of the cutting cylin- der a, producing the operation of cropping or shearing the pile. Upon the cutting cylinder, between the spiral blades, it is proposed to place stripes cf plush, to answer the purpose of brushes, to raise ihe Eap or pile as the cylinder gotff around, and thereby assist in bringing the points of the wool up to the cutters. The same contrivance is adapted to a machine for shearing the cloth lengthwise. mmmmmtm mm^ ^^ifsY^ WOOLLEN MANUFACTURE. 981 Fig, 1562, is a geometrical elevation of one side of Mr. Davis's machine. Fig. 1563, a plan or horizontal representation of the same, as seen in the top; and fig. 1564, a sec- tion taken vertically across the machine near the middle, for the purpose of display- ing the working parts more perfectly than in the two preceding figures. These three figures represent a complete machine in working condition, the cutters being worked by a rotatory motion, and the cloth so placed in the carriage as to be cut from list to list, a, a, a, is a frame or standard, of wood or iron, firmly bolted together by cross braces at the ends and in the middle. In the upper side-rails of the standard. there is a series of axles carrying anti-friction wheels 6, 6, 6, upon which the side-rails c, c, of the carriage or frame that bears the cloth runs, when it is passing under the cutters in the operation of shearing. The side-rails c, c, are straight bars of iron, formed with edges r, on their under sides, which run smoothly in the grooves of the fillers b, b, b. These side-rails are firmly held together by the end stretchers d, d. The sliding frame has attached to it the two lower rollers c, e, upon which the cloth intended to be shorn is wound ; the two upper lateral rollers/,/, over which the cloth is conducted and held up ; and the two end rollers g, g, by which the habiting rails h,h, are imwa tight. In preparing to shear a piece of cloth, the whole length of the piece is, in the first place, tightly rolled upon one of the lower rollers e, which must be something longer than the breadth of the cloth from list to list. The end of the piece is then raised, and passed over the top of the lateral rollers /, /, whence it is carried down to the other roller c, and its end or farral is made fast to that roller. The hooks of the ha- biting rails hf A, are then put into the lists, and the two lower rollers e, e, with the two end rollers g, g, are then turned, for the purpose of drawing up the cloth, and straining it tight, which tension is preserved by ratchet wheels attached to the ends of the re- spective rollers, with palls dropping into their teeth. The frame carrying the cloth is now slidden along upon the top standard rails by hand, so that the list shall be brought 982 WOOLLEN MANUFACTURE. WOOLLEN MANaFACTURE. 983 learly up o the cutter i, i, ready to commence the shearing operation ; the bed is then raised, which brings the cloth up against the edges of the shears. ' "*^ ^ " ^Hea Ihe construction of the bed will be seen by reference to the cross section,/^. 1564. 1564 ft consists of an iron or other metal roller k, k, turned to a truly cylindricalfigure, and covered with cloth or leather, to afford a smaU degree of elas. ticily. This roller is mounted upon pivots in a frame /, /, and is suppor- ted by a smaller roller»n,similarly mounted, which roller m, is in- tended merely to prevent any bending or de- pression of the \e:^zv,f::zt'^i^r '''' ^'^ ^^^^^ ^^^^ ^ ^^^^^^ ^^- contacrw!t?\hr;u In order to allow the bed k to rise and fall, for the purpose of bringing the cloth uo to km?/ 7 'va' '^^'"J °; ^""^^""^ '' ^^^y ^'•^"^ '^^^ af^e^ the oper\t"L, the frame^/ I wirn ,h ']'^V%^u^ ^^r ^" '^^ ^'^^'^ ^^^"^^'•d »»' »»> the moveable part encLsed wi hm the standard being shown by dots. This standard n, is situated about he mddle of the mach.ne, crossing it immediately under the cutters, and is made fast to he fr^me a by bolts and screws There s a lever o, attached to the lower cross-rail of the sLndar J tie .PntrnfT" ,^^"^^7°»-P^"' t\^ -^tremity of the shorter arm of which lever acts under' the centre of the slidmg-frame, so that by the lever o, the sliding.frame, with the bed mav be raised or lowered, and when so raised, be held u^ by a spring catch j. ' ^ . ni r"'\!;°'^ explained by what means the bed which supports the cloth is constructed ^"1 Tf "^' '° ^'.*^ ^'"P.*^" *^'«^^ '^ "^^^'^ e°»t«ct wilh the cutters, whirtheopS^.' of the cutTL^^^^^ "V 'I '' "I'^'^^T '"^ '^« "^^^ ^'^'^ t« describe'the constructron in he firl th;^" fi ' '^^^ ""^ '^'''^'''^ ' ^^^ ^^'^h purpose, in addition to what is show, in ^g! 1565! ^'"'^'' ' ^'^ ^^^ represented detached, and upon a larger scale. In this figure is exhibited a portion of the cutters in the same situation as in fig- 'IM_"' p\ rrC=^^^ 1565 ^ ^^ 1559 ; and alongside of it is a section of i lilhvNSi;'!' /^^^=^ T ^^ »^^^m the same, taken through it at right angles to the former ; ;>, is a metallic bar or rib, somewhat of a wedge form, which is fastened to the top part of the rri 1 • 1. . , standard a, a, seen best in He. 1558 To this bar a straight blade of steel g, is attached by screws, the edge of which stands forward even with the centre or axis of the cylindrical cutter f, and forms the ledger blade. ^'^kT,!' ^m^^ ^^^^ ""^c^^^ '^*^'''- "^his blade remains stationary, and is in close contac wiUi the pile or nap of the cloth, when the bed k is raised, in the manner above described. The cutter or upper blade of the shears is formed by inserting two or more strips of plate steel r,r, in twisted directions, into grooves in the metallic cylinder «, t, the edges o which blades r, as the cylinder t revolves, traverse along the edge of the fixed or ledger b ade g and by their obliquity produce a cutting action like shears ; the edses of the two blades taking hold of the pile or raised nap, as the cloth passes under it, shaves off the superfluous ends of the wool, and leaves the face smooth. Rotatory motion is given to the cuttin? cylinder », by means of a band leading from the wheel s which passes round the pulley fixed on the end of the cylinder t, the wh?el * being driven by a band leading from the rotatory part of a steam-engine, or any other first mover, and passed round the rigger /, fixed on the axle «. Tension is given to this band by a Ughtening pulley « mounted on an adjustable sliding-piecer, which is secured to the stand- ard l)y a screw; and this rigger is thrown in and out of gear by a clutch-box and lever, which sets the machine going, or stops it. In order to^ive a drawing stroke to the cutter, which will cause the piece of cloth ID be shorn off with better effect, the upper cutter has a slight lateral action, produced Vt the axle of the cutting cylinder being made sufficiently long to allow of »ts sbding laterally about an inch in its bearings ; which sliding is effected by a cam tc, fixed at one end. This cam is formed by an oblique groove, cut round the axle (see «', ^g. 15b&;, and a tooth ar, fixed to the frame or standard which works in it, as the cylinder revolves. By means of this tooth, the cylinder is made to slide laterally, a distance equal to the obUquity of the groove w, which produces the drawing stroke of the upper shear, in order that the rotation of the shearing cylinder may not be obstructed by fncUon, the tooth X, is made of two pieces, set a little apart, so as to afford a small degree of elasticity. The manner of passing the cloth progressively under the cutters is as follows:— Un the axle of the wheel «, and immediately behind that wheel, there is a small rigger, from which a band passes to a wheel y, mounted in an axle turning in bearings on the lower tide-rail of the standard a. At the reverse extremity of this axle, there is another smaU rieeer 1, from which a band passes to a wheel 2, fixed on the axle 3, which crosses near the middle of the machine, seen in yig. 1564. Upon this axle there is a sliding pulley 4, round which a cord is passed several times, whose extremities are made fast to the ends of the sliding carriage d; when, therefore, this pulley is locked to the axle, which »s done by a clutch box, the previously described movements cf the machine cause the pulley 4 to revolve, and by means of the rope passed round it, o draw the frame, with the cloth, slowly and progressively along under the cutters. ., ,r ,• It remains only to point out the contrivance whereby the machinery throws itselt out of gear, and stops its operations, when the edge of the cloth or list arrives at the cutters. At the end of one of the habiting rails /i, there is a stop affixed by a nut and screw o, which by the advance of the carriage, is brought up and made to press against a lever 6- when an arm from this lever 6, acting under the catch 7, raises the catch up, and allows the hand-lever 8, which is pressed upon by a strong spring, to throw the clutch- box 10 out of gear with the wheel 8 ; whereby the evolution of the machine instanUy ceases' The lower part of the lever 6, being connected by a joint to the top of the lever i the receding of the lever 6, draws back the lower catch j, and allows the sliding frame L /, within the bed fc, to descend. By now turning the lower rollers e, e, another portion of the cloth is brought up to be shorn ; and when it is properly habited and strained, by the means above described, the carriage is slidden back, and, the parts being all throw:* into gear, the operation goes on as before. ^ ^. ^ v Mr. Hirst's improvements in manufacturing woollen cloths, for which a patent was o^. tained in February, 1830, apply to that part of the process where a permanent lustre M fiven usually by what is called roll-boiling; that is, stewing the cloth, when tighUy wound upon a roller, in a vessel of hot water or steam. As there are many disadvanta- ges attendant upon the operation of roll-boiling, such as injuring the cloths, by over- heating them, which weakens the fibre of the wool, and also changes some colors, he substituted, in place of it, a particular mode of acting upon the cloths, by occasional or intermitted immersion in hot water, and also in cold water, which operations may be per- formed either with or without pressure upon the cloth, as circumstances may require. The apparatus which he proposes to employ for carrying on his improved process, is shown in the accompanying drawing. JPig. 1566, is a front view of the apparatus, com- plete, and in working order; jig. 1567, is a section, taken transversely through the mid- dle of the machine, in the direction of yig. 1568 ; and yig. 1568, is an end view of the tame • a, a, a, is a vessel or tank, made of iron or wood, or any other suitable material : •lopii^ at the back and front, and perpendicular at the enfis. This tank must be sufll- 984 WOOLLEN MANUFACTURE. cicnlly large to admit of half the diameter of the cylinder or drum h h k w^- • ^ into it, which drum is about four feet diameter, and ab^uts"?feenn;^*"^ immtnB(t more than the width of the piece of cloth intended to Se operateSt^^^^^^^ or drum b, b, is construct- ed by combining segments of wood cut radially on their edges, secured by screw-bolts to the rims of the iron wheels, having arms, with an axle pass- ing through the middle. The cylinder or drum being thus formed, ren- dered smooth on its pe- riphery, and mounted up- on its axle in the tank, the piece of cloth is wound upon it as tightly as possible, which is done by placing it in a heap upon a stool, as at c. Jig, 1567, passing its end over jx^llers d e, and then securing it to the drum, the cloth is progTefsllTeM^^awn ^mthe' toV^V^\sllZ?^r//7^"^^ ?"^'- '"'V^ ''^"" ^"^ P"^^ ^^^«^>»t »« "«w filled 10 me brim, as shown at fig. 1567, and opening the stop-cock of the pipe /, which leads *■ ^[on^ a boiler, the steam is allowed to blow through the pipe, and discharge itself at the lower end, by which means the tem perature of the water is raised in the tank to about 170° Fahr. Before the tempera- ture of the water has got up, the drum is set in slow rotatory motion, in order that the cloth may be uniformly heated through- out ; the drum making about one rotation per minute. The cloth, by immersion in the hot water, and passing through the cold air, in succession, for the space of about eight hours, gets a smooth soft face, the texture not being rendered harsh, or otherwise injured, as is frequently the case by roll-boiling. Uniform rotatory motion to the drum is shown in fig. 1566, in which g is an end- less screw or worm, placed horizontally, first mover employed in the factorv Th!^ ^n^ut T^"^ ^f f steam-engine or any other drives, the verU wheel I u rthel o7 wtL'^c tlL^tx^'^' ^ 5 '^ consequently, continually revolves with it At the end ^thoT?; r \ '' '/ ^""^^ ^"'^^ of sliding clutches fc, fc, are mounted whiih when nrolr-^S r *" f the drum, a pair in fig. 1566, produce the coupling or irkin- Tf the drZ «h J^i;'^^*!;'^' r. '•^'^^'^ ^^ ^°^» Which the drum is put ia motion ; buton withdrawing tt^nf^ ^ ^ u t'T^ ^'^"'^' ^^ ling-box f, ,-, as in L figure, the' drrrmreSy'^sfaid's s m '^ ^' ^' '"" ^'^ ^^"^ After operating upon the cloth in the way described hv^lcl* •» .u for the space of time required, the hot wrter is o be withir^rK^ '^ through hot water •r otherwise, and cold water rntroducerinto tL tank^n^l Z^ ^ '°\^. ^i ^he bottom, the cloth is to be continued turning, in the manner ^wl/ '' ^i!J^'''^ .^^^^ ^^^^'- twenty-four hours, which will perfect!^ fix tL Se thatch? ^/^"^i; ^^'^! l^^*'" «' quired by its immersion in the hot water, and leave the nieorn«n f^^^V^""'^ .^^' *^ silky state. ' ^ P"^ ^^ "»P> to the touch, m a soft beLVpJe'dTl^^^^^^^^^^ roller , which, over the back of the cloth as it goes round. T^7Z\:fL'''::!'.'l ttVn"l2f WOOLLEN MANUFACTURE. 985 doth with any required pressure, bv depressing the screws m, m, or by the employ- ment of weighted levers, if that should be thought necessary. Pressing ia the last finish of cloth to give it a smooth level surface. The piece is folded backwards and forwards in yard lengths, so as to form a thick package on the board of a screw or hydraulic press. Between every fold sheets of glazed paper are placed to prevent the contiguous surfaces of the cloth from coming in contact; and at the end of every twenty yards, three hot iron plates are inserted between the folds, the plates being laid side bv side, so as to occupy the whole surface of the folds. Thin sheets of iron not heated are also inserted above and below the hot plates to moderate the heat When the packs of cloth are properly folded, and piled in sufficient number in the press, they are subjected to a severe compression, and left under its influence till the plates get cold. The cloth is now taken out and folded again, so that the creases of the former folds may come opposite to the flat faces of the paper, and be removed hj a second pressure. In finishing superfine cloths, however, a very slight pressure is given with iron plates but moderately warmed. The satiny lustre and smoothness given by strong compression with much heat is objectionable, as it renders the surface apt to become spotted and disfigured by rain. Ross's patent improvements in wool-combing machineri/, March 13, 1851. — The first improvements described have relation to the machine for forming the wool into sheets of a nearly uniform thickness, technically known as the "sheeter," and consist chiefly in combining with the ordinary sheeting drum or cylinder rollers, designated, from their resemblance to porcupine quills, porcupine rollers; these rollers having their teeth or auills set in rows, and the rows of one roller gearing or taking into the spaces between le rows of the other. JPig. 1569 is an elevation of a sheeting machine thus constructed: — f r is the gen- eral frame work upon which the several working parts of the machine are mounted. A is the main or sheeting drum or cylinder, which is studded with rows of comb or "porcupine " teeth a, a, o, the length and fineness of which are varied according to the length of the staple of the wool or other material to be operated upon. Instead of the rows consisting each of a single set of teeth, two, three, or more sets may be com- bined together. The number of wires which may be placed on one line should vary with the quality of the wool or other material. In long staple machines, the number may vary from four to ten or more, and in short staple machines from five to twenty and more perinch. b, b, are two fluted feed-rollers, c, c, two porcupine combing rol- ler^ by which the wool is partly combed while passing from the feed rollers to the surface of the sheeting drum ; an end elevation of the porcupine combing rollers on an enlarged scale is given at fig. 1570. The teeth c, c, are set in rows, and the rows of one roller take or gear into the spaces between the rows of the other, d is a grooved guide roller for preventing the wool or other material escaping the combing action. The wool or other material is laid by the attendant evenly upon the upper surface of an endless webb g, which works over the under feed rollers, and a plain roller h, which 18 mounted in bearings on the front of the machine. The feed rollers gradually supply the wool thus spread upon the endless web to the two porcupine combing rol- lers, where it is partly combed and separated, and being so prepared, it is laid hold Of by the teeth of the sheeting drum, by which it is still further drawn out on account of the greater velocity with which the surface of the sheeting drum travels. When a 'M: 986 WOOLLEN MANUFACTURE. sufficient quantity of the wool or other material has been thus collected on the sur- face of the drum, it is removed by the attendant passing a hooked rod across the sur- fiaoe of the drum, and raising up one end of the sheet, when the whole may be easily stripped off and removed, being then in a fit state for being supplied to the comb-filline machine, next to be described. ° A modification of this sheeting machine is represented in^^s. 167 1, 16Y2, which differs from it m this, that it is fed from both ends. In this modification a double set of feed- ing rollers is employed, so that the machine may be fed from both ends. These rollers are grooved and gear into porcupine combing rollers similar to those before described which are followed by brush cylinders or grooved guide rollers, a is the sheeting drum as before; B, b, the fluted feed-rollers, c, c, the porcupine combing rollers, which gear into the fluted ones; d, d, are the grooved guide rollers; f, k, are brush cylinders, which may in case of long work be dispensed with; g, g, are the endless webs upon which the wool is laid. The framing and gearing by which the several parts are put in mo- tion are oinitted m the drawings, for the purpose of clearly exhibiting the more impor- tant working parts of the machine. The arrangement of sheeting machines just de- scribed, in so far as regards the employment of a fluted feed roller in conjunction with a porcupine combing roller, and grooved guide roller, is more especially applicable to sheeting fine short wool, but may also be applied with advantage to wool or other ma- tenal of a longer staple. In the case of fine short wool, the sheet may be drawn off by means of rollers, in the manner represented in/^. 1672 : h, a are the drawing or straightening rollers, and i the receiving rollers. During the operation of drawing the wool and winding it on the receiving roller, the sheeting cylinder must have a motion imparted to it m the reverse direction. The next head of Mr. Ross's specification embraces several improvements in comb- HlJing machines, which have for their common object the partial combing of the wool while it 18 in the course of being filled into the combs. We select for exemplification What the patentee regards as the best of these arrangements:/^. 1678 is aside elevation of a comb-fillmg machine as thus improved, a, a, is a skeleton drum, which is composed WORSTED MANUFACTXJRE. 987 of two rings a a, afiixed to the arms b b, which last are mounted upon the main shaft of the machine, which has its bearings upon the general frame f, f; b1, b2 are the por- cupine combing rollers, and ci, c2 brushes by which the porcupine combing rollers cleansed from the wool that collects upon them, and by which the wool is again de- livered to the combs e, e ; i>, d, are the feed-rollers, and e an endless web which runs over the lower feed-roller and the plain roller g, which is situated at the front of the machine; h, h, are the driving pulleys, by which the power is applied to the machine, and I, I, I, the wheel gearing by which motion is communicated to the different parts. The wool which has undergone the process of sheeting in the machine first described is spread upon the endless web k, and in passing between the feed-rollers, and between or under or over the porcupine combing rollers, is taken hold of by the combs e, e, as they revolve, and, being drawn under the first porcupine roller fil and the brush ci, the continued revolution of the drum and combs causes the wool to be brought into contact with the other porcupine combing roller b2 and brush c2. As the combs get filled, the wool is thus continuously being brought under the action of the porcupine combing rollers and brushes; and each new portion of the wool taken up is instantly combed out For some purposes the combing will be found carried so far by this operation that the wool will require no further preparation previous to being formed into slivers in the machine just described, and which is calculated for filling the combs and combing the wool or other fibrous material, when the staple is some considerable length (say from 4 to 16 inches), there are two porcupine comb rollers with their brushes employed; but I do not confine myself to that number, as in some cases a single porcupine combing roller and brush will be found sufficient for the purpose of facilitating the process of combing and filling the combs; three or more rollers and brush cylinders may be used with ad- vantage ; such as where the staple is short, or where the fibrous material operated upoa is very close, and separated with difficulty. Mr. Ross next describes some improvements in the combing machine of his invention patented in 1841, and now extensively used. The following general description will indicate with sufficient distinctness to those familiar with the machine, the nature of the improvements. "First. I give to the saddle combs in the said machine a compound to-and-fro and up-and-down movement, whereby they recede from and advance towards the comb gates, and simultaneously therewith alternately rise and fall, so that each time the comb gates pass the saddle combs, they do so in a different plane, and thus the position of the combs in relation to each other, as well as to the hold they take of the wool or other material, is constantly being changed. Secondly, I employ a fan to lash the wool in the comb gate or flying comb up against the saddle comb, which renders it im- possible for the wool to pass by the saddle comb without being acted upon by it. Thirdly, I attach the springs by which the gates are actuated to the lower arms of the combing gates, instead of their being placed parallel to the upright shaft of the machine as formerly, whereby a considerable gain in space and compactness is effected ; and, fourthly, I use brakes to prevent the sudden jerk which is caused when the wool in the comb gate leaves its hold of the saddle comb or incline plane, and also to counteract the sudden recoil of the springs by which the comb gates are pressed in when these springs are released from the grip or pressure of the incline plane." Mr. Ross concludes with a description of an improved method of heating the combe which has for its object "the economizing of fuel, the better heating of the comb% and mmf^mm^ 988 YEAST. the prevention of mistake in removing the combs before they have been a sufficient time exposed to the heat" The body of the heating box or stove is divided by a partition into two portions, which communicate together at the back or further end of the stove, so that the flame and heated vapors, after having circulated under and along the sides of the two lower comb chambers, ascend into the upper portion of the stove, where they have to traverse along the sides and over the top of the two upper chambers, ultimately escaping into the chimney through a pipe. The length of the heating box, or the chambers, should be about double the length of the comba The cold combs are inserted at one end, and on being put into their places push the more heated combs towards the other end of the chambers, from which they are removed. WOOTZ, is the Indian name of steel. WORSTED and WOOLLEN MANUFACTURR 812,500 people employed; pro- ducmg an annual value of £26,000,000. Dewsbury is famous for tearing up old worn cloth and working the woollen stuff into new goods of a cheap description. Alpaca is an animal of the Llama tribe, inhabiting the mountain region of Peru. The wool or hair is of various shades of black, white, gray, brown, Ac, and is remark- able for brightness of lustre, great length of staple, and extreme softness. This wool was brought into general use in this country about 16 years ago, by the Earl of Derby. Since that time the various obstacles in the way of its successful working have been overcome, and the alpaca manufacture now ranks as one of the most important branches of the Bradford worsted stuff trade. The articles produced from alpaca in combination with silk are especially noticeable for their softness and brilliancy. The bulk of the goods, however, is made with cotton warp, and when dyed and finished approach in lustre to silk. The following is the average yearly importation of alpaca wool into England since its first introduction, viz. : _ Annual. From 1836 to 1840 - - - - 7,000 bales 1841 1845 .... 13,000 1846 1860 .... 20,000 being supposed to be the ultimate limit of the Peruvian production. Mohair or goat's wool is produced exclusively in Asia-Minor. In its raw state it is 6uj)erior m lustre to alpaca, and it is wrought into many beautiful fabrics. The impor- tation of this article has increased from 5,621 bales in 1841 to 12,884 in 1850. WORT, is the fermentable infusion of malt or grains. See Beer, and Malt. WOULFE'S APPARATUS, is a series of vessels, connected by tubes, for the purpose of condensing gaseous products in water. See Acetic Acid, M 1 ; also MuKiATio Aom. X. ^ XANTHINE, is the name given by Kuhlmann to the yellow dying matter contoined in madder. T. YEAST, is the froth of fermenting worts. See Beer and FERMEXTATioif. Dr. Liidersdorff supports the theory that yeast is an organic body, and acts by means of its organs on sugar, in contradistinction to the theories of its action by mere contact, or by Its own state of decomposition inducing a similar state in the saccharine solution by the following experiment:— A portion of yeast was rubbed between ground glass plates until the globules, of which It js composed, could no longer be distinguished by the microscope, and its organic structure therefore was destroyed. An equal portion was exposed, moistened in a thin layer to the air, whilst the other was being thus treated. Both portions were now mixed separately with equal quantities of grape sugar, dissolved in 10 parts of water and exposed to a temperature of 95^ F. The portion containing the uninjured yeast began to ferment in half an hour, and continued to do so until the whole of the sugar was decomposed. The mutilated yeast did not produce a single gas bubble in the fluid containing it during the whole of this time. YEAST ARTIFICIAL. Mix two parts, by weight, of the fine flour of pale barley malt with one part of wheat flour. Stir 60 pounds of this mixture gra- ZIMOME. 989 dually into 100 quarts of cold water, with a wooden spatula, till it forms a smooth pap. Put this pap into a copper over a slow fire ; stir it well till the temperature rise to fully 155° to 160°, when a partial formation of sugar will take place, but this sweet- ening must not be pushed too far; turned out the thinned paste into a flat cooler, and Btir it from time to time. As soon as the wort has fallen to 59° Fahr., transfer it to a tub, and add for every 50 quarts of it, 1 quart of good fresh beer-yeast, which will throw the wort into brisk fermentation in the course of 12 hours. This preparation will be good yeast, fit for bakers' and brewers' uses, and will continue fresh and active for three days. It should be occasionally stirred. When beer-barm has become old and flat, but not sour, it may be revived by mixing with every quart of it a small potato, boiled, peeled, and rubbed down into a paste. The mixture is to be placed in a warm situation, where it will speedily show its renewed activity, by throwing up a froth upon its surface. It must be forthwith incorporated with the dough, for the purpose of baking bread. When the barm has become sour, its acid should be neutralised with a little powdered carbonate of soda, and then treated as above, when it will, in like manner, be revived- A bottle of brisk small beer may furnish ferment enough to form, in this way, a supply of good yeast for a small baking. The German yeast imported into this country in large quantities, and employed by our bakers, in baking cakes, and other fancy bread, is made by putting the unterhefe (see Beer, Bavarian) into thick sacks of linen or hempen yarn, letting the liquid part, or beer, drain away ; placing the drained sacks between boards, and exposing them to a graduallly increasing pressure, till a mass of a thin cheesy consistence is obtained. This cake is broken into small pieces, which are wrapped in separate linen cloths; these parcels are afterward enclosed in waxed cloth, for exportation. The yeast cake may also be rammed hard into a pitched cask, which is to be closed air-tight. In this state, if kept cool, it may be preserved active for a considerable time. When this is to be used for beer, the proportion required should be mixed with a (Quantity of worts at 60° Fahr., and the mixture left for a little to work, and send up a lively froth; when it is quite ready for adding to the cooled worts in the fermenting back. Yeast, Patent. Boil 6 ounces of hops in 3 gallons of water 3 hours : strain it off. and let it stand 10 minutes; then add half a peck of ground malt, stir it well up, and cover it over; return the hops, and put the same quantity of water to them again, boiling them the same time as before, straining it off to the first mash ; stir it up, and let it remain 4 hours, then strain it off, and set it to work at 90°, with 3 pints of patent yeast; let it stand about 20 hours; take the scum off the top, and strain it through a hair sieve ; it will be then fit for use. One pint is sufficient to make a bushel of bread. YELLOW DYE. (Tehiture jauney Fr. ; Gelhfarhen, Germ.) Annotto, dyer^s-broom^ (GenUta tinctoria^) fuslic, fustet, Persian or French berries, quercitron barky saw-wort, (Strratula tincforia,) turmeric, weld, and willow leaves, are the principal yellow djes of the vegetable kingdom ; chromatc of lead, iron-oxyde, nitric acid, (for silk,) sulphurei of antimony, and sulphuret of arsenic, are those of the mineral kingdom. Under these articles, as also under Calico-printing, Dyeing, and Mordants, ample instructions will be found for communicating this color to textile and other fibrous substances. Alumina and oxyde of tin are the most approved bases of the above vegetable dyes. A nankin dye may be given with bablah, especially to cotton oiled preparatory to the Turkey red process. See Madder. YELLOW, KING'S, is a poisonous yellow pigment. See Arsenic and Orpiment. YTTRIA, is a rare earth, extracted from the minerals gadolinite and yttrolantalite^ being an oxyde of the metal yttrium. z. ZAFFRE. See Cobalt. ZEDOARY, is the root of a plant which grows m Malabar, Ceylon, &c. It occurs in wrinkled pieces, externally ash-colored, internally brownish-red ; possessed of a fra- grant odor, somewhat resembling camphor ; and of a pungent, aromatic, bitterish taste. It contains, according to Bucholz, 1*42 of volatile oil, of a burning camphorated taste; 3*60 of a soflt, bitter, aromatic resin; 11*75 of a bitter aromatic extract, mixed with a little resin and potash-salts ; 4*5 of gum ; 9 of vegetable mucilage ; 3'60 of starch ; 8*0 of a starchy extract from the woody fibre, by means of caustic potassa, along with 31*2 of another matter, 12-89 of woody fibre, and 15 of water. According to Morin, this root contains, besides, an azotized substance, analogous to the extract of beef. ZIMOME, is a principle supposed by Taddei to exist in the gluten of wheat-flour. Its identity is not recognised by later chemists. 1 990 ZINC. ZINC, is a metal of a blnish-white color, of considerable lustre when brok^ across, but easily tarnished by the air; its fracture is hackly, and foliated with small facets, irregularly set. It has little cohesion, and breaks in thin plates before the ham- mer, unless it has been previously subjected to a regulated process of lamination, at the temperature of from 220° to 300° F., whereby it becomes malleable, and retains its mal- leability and ductility afterwards. On this singular property, a patent was taken out by Messrs. Hobson and Sylvester, of Sheffield, many years ago, for manufacturing sheet zinc^ for covering the roofs of houses, and sheathing ships ; but the low price of copper at that time, and its superior tenacity, rendered their patent ineffective. The specific gravity of zinc varies from 6-9 to 7'2, according to the condensation it has received. It melts under a red heat, at about the 680th or 700th degree of Fahrenheit's scale. When ex- posed to this heat with contact of air, the metal takes fire, and burns with a brilliant bluish-white light, while a few flocculi, of a woolly-looking white matter, rise out of the crucrble, and float in the air. The result of the combustion is a white powder, formerly called flowers, but now oxyde of zinc; consisting of 34 of metal, and 8 of oxygen, being their respective prime equivalents ; or, in 100 parts, of 81 and 19. The principal ores of zinc are, the sulphuret called blende, the silicate called calamine, and the sparry calamme, or the carbonate. 1. Blende crystallizes in the garnet-dodecahedron ; its fracture is highly conchoidalj lustre, adamantine ; colors, black, brown, red, yellow, and green ; transparent or trans- lucent; specific gravity, 4. It is a simple sulphuret of the metal; and, therefore, con- sists, in its pure state, of 34 of zinc, and 16 of sulphur. It dissolves in nitric acid, with disengagement of sulphureted hydrogen gas. It occurs in beds and veins, accompanied chiefly by galena, iron pyrites, copper pyrites, and heavy spar. There is a radiated variety found at Przibram, remarkable for containing a large proportion of cadmium. Blende is found in great quantities in Derbyshire and Cumberland, as also in Cornwall. 2. Calaminey or silicate of zinc, is divided into two species ; the prismatic or electric calamine, and the rhomboidal ; though they both agree in metallurgic treatment. The first has a vitreous lustre, inclining to pearly; color, white, but occasionally blue, green, yellow, or brown ; spec. grav. 3-38. It often occurs massive, and in botroidal shapes. This species is a compound of oxyde of zinc with silica and water ; and its constituents are— zinc oxyde, 66-37; silica, 26-23; water, 7-4; in 100 parts. Reduced to powder, it is soluble in dilute sulphuric or nitric acid, and the solution gelatinizes on cooling. It emits a green phosphorescent light before the blowpipe. The second species, or rhombohedral calamine, is a carbonate of zinc. Its specific gravity is 4*442, much denser than the preceding. It occurs in kidney-shaped, botroidal, stalactitic, and other imitative shapes ; surface generally rough, composition columnar. Massive, with a granular texture, sometimes impalpable; strongly coherent. According to Smith- son's analysis, Derbyshire calamine consists of— oxyde of zinc, 65-2 ; carbonic acid, 34*8 r which coincides almost exactly with a prime equivalent of the 'oxyde and acid, or 42 -i 22 = 64. ' > -r The mineral genus called zinc-ore, or red oxyde of zinc, is denser than either of the above, its spec. grav. being 5*432. It is a compound of oxyde of zinc 88, and oxyde of iron and manganese 12. It is found massive, of a granular texture, in large quantities, in several localities, in New Jersey. It is set free in several metallurgic processes, and occurs crystallized in six-sided prisms of a yellow color, in the smelting-works of Koenig- shutte in Silesia, according to Mitscherlich. The zinc ores of England, like those of France, Flanders, and Silesia, occur in two geological localities. The first is in veins in the carboniferous or mountain limestone. The blende and the calamine most usually accompany the numerous veins of galena which traverse that limestone ; though there are many lead mines that yield no calamine ; and, on the other hand, there are veins of calamine alone, as at Matlock, whence a very considerable quantity of this ore is obtained. In almost every point of England where that metalliferous limestone appears, there are explorations for lead and zinc ores. The neighborhood of Alston-moor in Cumber- land, of Castleton and Matlock in Derbyshire, and the small metalliferous belt of Flint- shire, are peculiarly marked for their mineral riches. On the north side of the last county, calamine is mined in a rich vein of galena at Holywell, where it presents the singular ap- pearance of occurring only in the ramifications that the lead vein makes from east to west, and never in those from north to south ; while the blende, abundantly present in this mine, is found indiflferently in all directions. The second locality of calamine is in the magnesian limestone formation of the English geologists, the alpine limestone of the French, and the zechstein of the Germans. The calamine is disseminated through it in small contemporaneous veins, which, running in all directions, form the appearance of network. These veins have commonly a thickness of only a few inches ; but in certain cases they extend to four fec^ ZINC. 991 in consequence of the union of several small ones into a mass. The explorations of calamine in the magnesian limestone, are situated chiefly on the flanks of the Mend ip Hills, a chain which extends in a northwest and southeast direction, from the canal of Bristol to Frome. The calamine is worked mostly in the parishes of Fhipham and Roborough, as also near Rickford and Broadfield-Doron, by means of a great multi- tude of small shafts. The miners pay, for the privilege of working, a tax of II. sterling per annum to the Lords of the Treasury ; and they sell the ores, mixed with a considera- ble quantity of carbonate of lime, for 11. per ton, at Phipham, after washing it slightly in a sieve. They are despatched to Bristol, where they receive a new washmg, in order to separate the galena. OF THE SMELTING OF THE ORES OF ZINC. The greater part of the zinc works are situated in the neighborhood of Birmingham and Bristol. The manufacture of brass, which has been long one of the staple articles of these towns, was probably the cause of the introduction of this branch of industry, at the period when brass began to be made by the direct union of copper with metallic zinc, instead of calamine. A few zinc furnaces exist also in the neighborhood of Sheffield, amid the coal-pits surrounding that town. Bristol and Birmingham derive their chief supply of ores from the Mendip Hills and Flintshire ; and Sheffield, from Alston-moor. . .... , . i • j v r •♦ • The calamine, freed from the galena by sorting with the hand, is calcined before its m- troduction into the smelting-furnaces, by being exposed, coarsely bruised, in reverberalory ovens, 10 feet long, and 8 broad, in a layer 6 inches thick. In some esUblishments the calcination is omitted, and the calamine, broken into pieces about the size of a pigeon s egg, is mixed with its bulk of small coal. Zinc is smelted in England, likewise from blende, (sulphuret of zinc.) This ore, after being washed, and broken into pieces of the size of a filbert, was sold a few years ao'o at the mine of Holywell for 31. a ton, or half the price of calamine. It is roasted, without any other preparation, in reverberatory furnaces ; which are about 8 feet wide, and 10 lont' ; the distance between the roof and the sole being 30 inches, and the height of the fire-bridge, 18. The layer of blende, which is placed on the hearth, is about 4 or 5 inches thick ; and it is continually stirred up with rakes. One ton of it requires, for roastin*', four tons of coals ; and it suflfers a loss of 20 per cent. The operation takes from 10 to 12 hours. The mixture of reducing consists of one fourth part of the desul^ phureted oxyde, one fourth of calcined calamine, and one half part of charcoal ; which aflTords commonly 30 per cent, of zinc. The En^'lish furnaces for smelting zinc ores are sometimes quadrangular, sometimes round ; the latter form being preferable. They are mounted with from 6 to 8 crucibles or pots (see /ig. 1574), arched over with a cupola a, placed under a conical chimney b, which serves to give a strong draught, and to carry oflf the smoke. In this cone there are as many doors c, c, c, as there are pots in the furnace ; and an equal number of vents d, d, d, in the cupola, through which the smoke may escape, and the pots may be set. In the surrounding walls there are holes for taking out the pots, when they become unserviceable ; after the pots are set, these holes are bricked up. The pots are heated to ignition in a reverberatory furnace before being set, and are put in by means of iron tong machinery supported upon two wheels, as is the case with glass- house pots, c, is the grate ; /, the door for the fuel ; g, the ash-pit. The pots h, h,h, have a hole in the centre of their bottom, which is closed with a wooden plug, when they are set charged with calamine, mixed with one seventh of coal ; which coal pre- vents the mixture from falling through the orifice, when the heat rises and consumes the plug. The sole of the hearth t, t, upon , _ ,^ which the crucibles stand, is perforated Wider each of them, so that they can be reached from below ; to the bottom orifice of the pot, when the distillation begins, a long sheet-iron pipe fe, is joined, which dips at its end Into a water vessel I, for receiving in drops the condensed vapors of the zinc. The pot 992 ZINC. u charged from above, through an orifice in the lid of the pot, which is left open altei ♦he firing, till the bluish color of the flame shows the volatilization of the metal} immediately whereupon the hole is covered with a fire-tile m. The iron tubes arc apt to get obstructed during the distillation, and must therefore be occasionally cleared out with a redhot rod. When the distillation is finished, the iron pipes must be removed ; the coaly and other contents of the pot cleared away. A pot lasts about four months upon an average. Five distillations may be made in the course of 14 days, in which from 6 to 10 tons of calamine may be worked up, and from 22 to 24 tons ol' coals consumed, with a product of two tons of zinc. The metal amounts to from 25 to 40 per cent, of the ore. 1, 2, is the level of the upper floor ; 3, 4, level of the lower ceiling of the lower floor. Fig. 1232, ground plan on the level of 1, 2 ; only one half is here shown. The zinc collected in this operation is in the form of drops, and a very fine powder, mingled with some oxyde. It must be melted in an iron pot or boiler, set in a proper furnace ; and the oxyde is skimmed off the surface, to be returned into the crucibles. The metal is, lastly, cast into square bars or ingots. The crucibles are discharged at the end of each operation, by withdrawing the conden- ser, breaking with a rake the piece of charcoal which shuts their bottom, and then empty- ing them completely, by shaking their upper part. In replacing the condenser-pipe k (sec second pot from the right hand, Jig. 1230), the flange at its top is covered with a ring of loam-lute, pressed against the conical bottom of the crucible, and secured in its place by means of two parallel rods o, o, which can be clamped by screws projecting hori- zontally from the vertical tunnel. See their piaces, indicated by two open dots near o, o. A smelter and two laborers are employed in conducting a furnace ; who make, with a mixture of eq'ial parts of fire-clay, and cement of old pounds finely ground, the pots or crucibles, which last about four months. Five charges are made in 15 days ; these work up from 6 to 10 tons of calamine, consume from 22 to 24 tons of coals, and produce 2 tons of zinc, upon an average. The following estimate of prices was made a few years ago :— 3 tons of calamine, at £6 ------ £18 24 ditto coal, at 5«. - A smelter, at 2 guineas a week ------ Two laborers, each at 4». per day - - - - - Incidental expenses -----... £29 18 The calamine of Alston-moor, used at Shefiield, is not so rich ; it produces at most only 25 per cent, of zinc. The coals are laid down at a cost of 5«. 8d. per ton ; and the cala mine laid down there 5/. ; whence the zinc will amount to 32/. lis. per ton. The con- siderable importations of zinc from Belgium and Germany, for some years back, have caused a considerable fall in its price. At Liitlich, where the calamine of Altenberg, near Aix-h-Chapelle, is smelted, a reduction furnace, containing long horizontal earthen tubes, is employed. The roasted calamine is finely ground, and mixed with from one third to two thirds its volume of coke or charcoal, broken to pieces the size of nuts. Fig. 1576 represents this zinc furnace in elevation ; and fig. 1577 in a vertical section through the middle. From the hearth to the bottom of the chimney it is 9 feet high, and the chimney itself is 18 or 20 feet high, a, is the ash-pit; 6, the grate ; c, the fireplace ; d, the hearth ; «, e, the laboratory ; /, the upper arch, which closes in the labor- atory ; /', the second arch, which forms the hood-cap of the furnace ; g, the chimney; h, the fire- wall, which rests against a supporting wall of the smelting-house. Through the vaulted hearth the flame of the fire draws through ten flues t, t, two placed in one line ; betwixt these five pairs of draught-openings, upon the sole of the hearth, the undermost earthen tubes fe, immediately rest. The second and third rows of tubes fe, Ar, lie in a parallel direction over each other, at about one inch apart; in the sixth row there are only two tubes ; so that At their two ends these tubes resl 6 2 2 2 16 1 1576 iPjesiraifMirwn there are 22 tubes altogether in one furnace. ZINC. 9dS vpon fire-tiles, which form, with the side-walls, a kind of checker-work /, I. The tubci are 4 feet long, 4 to 5 inches in diameter within, five fourths of an inch thick. The fir^ which arrives at the laboratory through the flues i, i, plays round the tubes, and passes off through the apertures m, m, in both arches of the furnace, into the chimney, n, it an opening in the front wall between the two arches, which serves to modify the draught by admitting more or less of the external air. The two slender side walls o, o, of the furnace, are a foot distant from the checker- work, so that on the horizontal iron bars y, 9, supported by the hooks />, />, the iron receivers r, r, may have room to rest at their fore part. These receivers are conical pipes of cast iron, 1^ foot long, posteriorly IJ inch, and anteriorly 1 inch wide at the utmost. After the earthen tubes have been filled with the ore to be smelted, these conical pipes are luted to them in a slightly slanting position. These cones last no more than three weeks; and are generally lengthened with narrow-mouthed wrought- iron tubes, to prevent the combustion of the zinc, by contact of air. When the furnace is in activity, a blue flame is to be seen at the mouths of all these pipes. Every two hours the liquefied metal is raked out into • shovel placed beneath ; and in 12 hours the charge is distilled ; after which the tubes are cleared out, and re-charged. 100 pounds of metallic zinc are the product of one operation. It is remelted at a loss of ten per cent., and cast into moulds for sale. Fig. 1578 is a longitudinal section of the fur- nace for calcining calamine in Upper Silesia; fig. 1579 is a ground plan of the furnace, a, is the orifice in the vault or dome, for the introductio* of the ore ; 6, 6, apertures in the side-walls, shu" with doors, through which the matter may ba turned over; c, the chimney; d, the fire-bridge j e, the grate ; /, the feed opening of the fire, the fuel being pitcoaL The calamine is stirred about every hour; and after being well calcined during 5 or 6 hours, it is withdrawn ; and a new charge is put in. These Silesian furnaces admit of 30 1579 w Ig" • y^y. cwts. at a time ; and for roasting every 100 cwts. 15 Prussian bushels of fuel, equal to 23 English bushels, are employed. 15B0 1581 These calcining furnaces are sometimes built along- side of the zinc smelting-furnaces, and are heated bf the waste flame of the latter. The roasting is per- formed in the Netherlands in shafts, like small blast iron-furnaces, called schachtofen. The hearth a, xnfigi. 1580, 1581, is constructed lor working with 5 muffles, one of which is long, and four short. The muffles are made upon moulds, of fire- clay mixed with ground potsherds. The receivers are stoneware bottles. The grate is ten inches be- neath the level of the hearth. 6, the firebridge, is proportionally high to diminisli the force of the flame upon the hearth, that it may not strike the muffles, c, is the opening through which the muffles are put in and taken out ; during the firing it is partly filled with bricks, so that the smoke and flame may escape between them ; rf, d, are openings for adjusting the positions of the muffles; c, cross hoops of iron, to strengthen the brick arch ; /, is a bed of sand under the sole of the-hearth. During the first two days, the fire is applied under the grating; the heat must be very slowly raised to redness, at which pitch it must be maintained during two days. From 8 to 10 days are required for the firing of the muffles. The furnace shown in figs. 1582, 1583, 1534. is for the melting of the metallic zinc. Fig. 1583 is a front view ; fig. 1582 a transverse section ; fig. 1584 a view from above ; a, is the fire-door ; 6, the trraie; c, the fire-bridge; d, the flue; e, the chimney; /ififi cast-iron melting-pots, which contain each about 10 cwts. of the metal. The heat IS moderated by the successive addition of pieces of cold zinc. The inside of the pota. should be coated with loam, to prevent the iron being attacked by the zinc. When the 994 ZINC. xinc is intended to be aminated, it should be melted with the lowest possible heat, tn< poured into hot moulds. When the zinc ores contain cadmium, this metal distils over in the fonn of brown oxyde, with the first portions, being more volatile than zinc. Under Brass and Copper, the most useful alloys of zinc are described. The sulphate, vulgarly called white vitriol, is made from the sulphuret, by roast- ing it gently, and then exposing it upon sloping terraces to the action of air and moisture, as has been fully detailed under Sulphate of Iron. The purest sulphate of zinc is made by dissolving the metal in dilute sulphuric acid, digesting the solution over some of the metal, filtering, evaporating, and ci7stallizing. Sulphate of zinc is added as a drier to japan var- nishes. The ordinary zinc found in the market is never pure ; but contains lead, cadmium, arsenic, copper, iron, and carbon ; from some of which, it may be freed in a great degree by distillation ; but even after this process it retains a little lead, with all the arsenic and cadmium. The separation of the latter is described under Cad- mium. Zinc, free from other metals, may be obtained by distilling a mixture of charcoal and its siubcarbonate, precipitated from the crystallized sulphate by carbonate of soda. By holding a porcelain saucer over the flame of hydrogen produced from the action of dilute sulphuric acid upon any sample of the zinc of commerce, the presence of arsenic in it may be made manifest by the deposite of a gray film of the latter metal. Antimony, how- ever, produces a somewhat similar efiect to arsenic. Zinc is extensively employed for making water-cisterns, baths, spouts, pipes, plates for the zincographer, for voltaic batteries, filings for fire-works, covering roofs, and a great many architectural purposes, especially in Berlin ; because this metal, after it gets covered with a thin film of oxyde or carbonate, sutfers no further change by long expo- sure to the weather. One capital objection to zinc as a roofing material, is its combusti- bility. ^.;; Chloride of zinc has been recently used with great advantage as an escharotic for removing cancerous tumors, and healing various ill-constitutioned ulcers. It, as also the aitrate, forms an ingredient in the resist pastes for the pale blues of the mdigo vat. ZINC. Mr. Nicholas Troughton, of Swansea, obtained a patent in May, 1839, for improvements in the manufacture of this metal. His invention relates to the appli- cation of a peculiar apparatus in roasting the ores, and in smelting the zinc. Fig. 1585, represents the section of a series of retorts for calcining zinc ores, arranged and con- structed according to this invention. The retorts shown in this figare are composed of « series of fire-tiles or parallelogram slabs, fl, a, a, are the slabs or tiles, which con- stitute the bottoms of the retorts; b, 6, are the slabs, which constitute the upper sur» faces or tops of the retorts ; and c, c, are slabs, placed vertically, to produce the sides of the retorts. The back ends of the retorts are closed by similar tilts or slabs, having a hole through them for the passage of the vapors evolved from the ores ; these vapors •re conveyed in any direction by the flue at that end, and being thus separated from the products of combustion, may be separately acted on, according to either of the patentee's former inventions, which treat of the separated vapors of copper ores in the process of "•ilcining or roasting such ores ; or the separated products of the ore may be allowed to pass into the atmosphere. The patentee states, that by treating zinc ores in furnaces or retorts, such as are above described, considerable saving of fuel will result, and the sine ore will be more evenly roasted or calcined. 41 1 ZINC. 995 The front ends of the retorts are closed by means of tiles or doors^ having a small hole or opening in each, for the passage of atmospheric air; and the holes may be closed, or more or less open, accordmg to the object required. The retorts are charged through the hoppers above, which have proper slides to close the openings into the retorts ; the quantity charged into each retort being sufficient to cover the lower surface thereof two or three inches deep. During the operation the ore must be raked from time to time, to change the surfaces, and the retorts should be kept to a moderate red heat. The second part of this invention relates to an arrangement of apparatus or furnace for calcining zinc ores, wherein the ore is subjected to the direct action of the products of combustion. J'ig. 1586, shows a longitudinal section of the furnace, which is so con- stracted that while one portion of the zinc ore is being heated in a manner similar to the working of an ordinary calcining surface, other zinc ore is going through a pre- paratory process by the heat that has passed away from the ore which is undergoing the completing process of calcining. This furnace may be heated by a separate fire, to burn by blast or by draught ; or the flue from the smelting furnace may be conducted into the entrance of this furnace, and the otherwise waste heat of the smelting furnace will be thus brought into useful application for calcining or roasting of zinc ore; and this part of the invention is applicable, whether it be applied to the furnace, or to the retorts herein-before explained, and will be found a means of saving much fuel in the processes of obtaining zinc from ore. «, ^g. 1586, represents the furnace, which is suitable for blast, and a constant supply of fuel is kept up in the chamber by there being a close cover, with a sand-joint, c, is the bed or floor on which the ore is spread, in like manner to an ordinary reverberatory furnace ; the ore is stirred about on the floor by passing the ordinary rakes or instruments through the openings, dy d ; and when the process has been sufficiently carried on, the ore is discharged through the openings €, e, which, at other times, remain closed by fire-tiles. The heat of the fire, and the flame thereof, passing in contact with the ore on the floor or bed, c, also acts on the roof,/, and that roof,/, being hot, reverberates the heat on to the floor or bed, at the same time the heat, which passes through the roof, heats the ore in the upper chamber, g; and, in addition to such heat passing through the roof, the flame and heat from the furnace, having passed over the zinc ore, in the lower compartment of the apparatus, enters into and passes over the ore m the chamber g ; and, in doing so, heats the roof A, of that chamber, and also the ore contained therein ; and it will be seen that there is a tliird chamber, t ; the heat, therefore, which passes through the roof h, heats the ore in the chamber i. In working this arrangement of calcining furnace or apparatus, when the charge is withdrawn from the lower chamber, the charge in the ehamber^ is to be raked into the lower chamber through the openings for that pur- pose, which, at other times, are kept covered with fire-tiles, as shown in the drawing; and the charge in the chamber i is to be raked into the chamber ff, and a fresh supply «f ore charged into the chamber L 996 ZINC. ZINC. 1588 The third part of this inrention relates to a mode of arranging a series of retorts side by side, aud of applying heat thereto in the process of smelting or distilling zinc from the ore. According to the practice most generally pursued in smelting zinc, the ore is sobmitted to the action of heat in crucibles, having descending iron pipes, which enter into vessels containing water : all which is well understood, as well as the process of smelting or distilling zinc from the ores. J'lg. 1587 is a side elevation of two seta of furnaces and retorts, arranged according to this invention, one of the furnaces being in section; and fq. 1588 is a transverse section of the same, a, a, are a series of retorts of fire-day, arranged, side by side, on a shelf of slabs or fire-tiles. These retorts are each closed at one end and open at the other, such open end being closed, when in ojjeration, by a tile or door, 6, fitting closely, and luted with fire-clay, as will readily be traced in the drawing. Each series of retorts is placed in a chamber, c, c, in such a manner that the heat and flame of the fire will pass from the fire-place or furnace, and act on one side of the retorts; and having passed along all the series, will proceed to the upper part of the chamber, c, c, and heat the other side of the retorts ; and as the fires are main- tained and urged by means of blasts of atmospheric air, the heat may be maintained and regulated with great advantage, and at comparatively small cost The blasts of air may be produced by any ordinary blowing machinery, but rotatory blowers are preferred, and the air may be cool or heated. When anthracite coal is used as the fuel, the patentee prefers adopting the hot blasts at a temperature of at least 500° Fahr., and such heating may be performed by any of the well-known means now very gene^ rally resorted to for heating the blasts of air for smelting iron, d, d, are iron pipee^ descending from the retorts and entering into vessels containing water, similar to the apparatus at present in use for like purposes. Each chamber, c, is heated by its separate furnace or fire-place, which have openings, to be closed when at work ; and in order to ^eep up a supply of fuel to the fire, each fire-place has an inclined chamber, e, which IS filled with fuel, and then closed air-tight by the cover,/, fitting into a sand-bath or joint, m order to prevent draught upwards. By this means the lower portion only of the fuel will be in an ignited state when at work, g, g, are a series of iron doors, one opposite the mouth of each retort; these doors are capable of being removed by sliding them upwards, till the portions cut out at the sides come opposite the dips or holders^ /«, h, when the doors may be removed, in order to get at the retorts, t, is a chamber in which the ore is heated previous to its being placed in the retorts. The arrange- ment of the brickwork, the construction and settling of the furnaces, being clearly fthown in the drawing, no further description need be given. The patentee remarks, that he is aware attempts have been made to employ retorts in the smelting of zinc, and he does not, therefore, claim the same generally; but he does claim, in respect to the third part of this invention, the mode of placing a series of retorts in a chamber, c, and causing the heat and flame to pass along, under and over, such series of retorts, as above described ; and he also claims the mode of smelting zinc by means of blast, whether the heat of the fuel is caused to act on a series of retorts or vessels, in the manner shown, or on other arrangements of retorts or vessels, placed in a suitable chamber or chambers. — Newton's Journal, C. S., xxiii. p. 81. ZINC PURIFYING, may be effected by melting the impure metal with lead in equal parts in a deep iron pot, stirring them well together, skimming off the impurities as they rise, covering the surface with charcoal to prevent oxidation, and keeping them in a fused state for three hours. The lead descends to the bottom by its greater den- sity, and leaves the zinc above, to be drawn off by a pipe in the side of the melting- pot. This contrivance is the subject of a patent granted to Mr. William Godfrey Kuel- ler in 1844. ZINC CASTING. The costliness of bronze precludes its employment as a material applicable to the purposes of monumental statuary almost entirely. On this account the extension of sculpture, with the increase in the number of private collections has been seriously impeded. This impediment^ however, is now being rapidly removed by the advances that have been made in the art of zinc-casting. The working on this metal as a medium for high art had at first to make good its progress against many preju- dices, chiefly on the part of artists themselves. In this lav the cause which long re- tarded Its progress in connection with sulphur, whereas, in d'omestic architecture, its ap- plication during the lasteighteen years has superseded tiiat of almost every other material. Every doubt has now been dispelled as to the comparative durability of zinc in the open air, and under the influence of every variety of weather. Chemistry has^ demon- strated this property of the metal Zinc is readily melted, liquefies very completely, and therefore is better adapted t» 997 I cover the smallest lines in the mould than metals of a harder and more compact tex- ture. The zinc casting is so pure and so finished, on being turned out of the mould, that the work requires but very little subsequent chasing. This circumstance, combined with the cheapness of the metal itself (the cost of a zinc cast being to a cast in bronze only one-sixth or one-eighth), renders zinc an admirable material for statuary. But the unfavorable color of the zinc proved, for a long time, a great obstacle in the way of its application to these purposes. This difficulty, however, through the indefatigable exertions of Mr. Kiss, the founder of this important branch af the art in Berlin, has been completely overcome. He has succeeded in imparting to the zinc a metallic surface, which gives to the cast the perfect aspect of Florentine bronze. The colossal group of the '^ Amazon," after Kiss of Berlin, cast in zinc and bronzed by M. Geiss, presents a striking specimen of the perfection to which the latter has brought this peculiar invention. The model of this group, cast in zinc by Geiss of Berlin, and lately deposited in the Great Exhibition, will establish the superiority of zinc over any other metal for similar purposes, so far as the elements of cheapness and solidity are concerned. ZINC PRINTING. Representations of the different departments of the Imperial establishment, etched on zinc, chemityped and printed with the common printing press — a new invention by Pul, for etching on zinc in a raised manner. If this art be not calculated to supersede wood engraving, it can be applied with great advantage for certain purposes in the etching style, for maps, plans, drawings of machines, Ac. A zinc plate is covered with an etching grmmd, the drawing etched in the usual manner with the needle, and bitten in. The etching ground is now removed, the deep lines cleaned with acid, and then the whole plate, in a warm state, covered with an easily fusible metal, with which, of course, the lines of the drawing are filled np. When the metal thus laid on is cold and firm, the whole plate is planed until the zino appears again, and only the lines of the drawing remain filled with the fusible metal, which is easily distinguished by its white color from the gray of the zinc. The whole plate is now etched several times; the former lines of the drawing, filled with this easily fusible negative metal, are not affected by the acid while the pure zinc is eaten away. In this manner a drawing for printing' in the copper-plate press can be con- verted into one in relief for use in the ordinary printing press. ZINKING OF IRON. Iron may be conveniently coated, in the humid way, by a solution of sulphate of zinc, or one of the double salt of chloride of zinc and sal am- oniac, as now used in soldering and welding. To secure success, the zinc solution should be weak, and only a weak galvanic current should be used, otherwise the zinc precipi- tated will again separate from the iron in scales. With proper precautions the deposit may be made as thick as strong paper. The article must be well cleansed before un- dergoing the operation. The sulphate is prepared by saturating with sulphurous gas as much hydrate of car- bonate of zinc, recently precipitated, as it will dissolve. For the compound salt, dis- solve one part of zinc in hydrochloric acid, and to this solution add one part of sal animoniac. Evaj^orate the liquor, and crystallize. The crystals are colorlet^s six-sided prisms, translucid, easily soluble in water, and very deliquescent. Zinked Iron weldable. — With a view to put this question to the test of experiment in the most severe manner, a piece of zinked iron wire rope was welded up into a bar, by Mr. James Nasmyth. In the first place it was found, that although the iron wire was quite covered with metallic zinc, which, although partially driven off in the process of welding, yet, so far from the presence of the metal, or its oxide, presenting any inipedimeut to the welding of the iron (is in the case of lead), the iron wire welded with remarkable ease: and the result was a bar of remarkably tough, silvery -grained iron, which stood punching, splitting, twisting, and binding, in a manner such as to show that the iron was not only excellent, but to all appearance, actually improved in quality in a very important degree. Encouraged by such a result, a still further and even more severe trial was made, viz., by welding up a pile of clippings of galvanised iron plates, or sheet iron covered with zinc, as in the former experiments. The presence of the zinc appeared to offer no impediment to the welding, and the result was a bloom or bar of iron, the fracture of result indicated from 5 to 10 percent. Iiij;her strength than the best samples of wrought iron, thus establishing the fact, that, so far from the presence of ziocLoing d*isti uc.tij^, to the strength and tenacity of wrought iron, the contrary ii tRe ca»5CH "' • • • • - * •*, I may mention, that bars of iron were heated to a welding J>e&t, prepared ^wi-siiefitk** ing, in the usual manner ; and, on drawing them from the fire, for being welded, a ■s^*«««R99l 998 ZIRCONIA. handful of zinc filings was thrown on the welding hot surface, and the welding pro- ceeded with. In this severe test no apparent impediment to the process resulted ; the iron welded as well as if no zinc had been present Judging from the appearance of the iron welded up from zinc covered iron scraps not only as respects its clear silvery aspect, but also the increased strength which such exhibited under proof, it may not be unreasonable to infer, that some important improvement might be made in the manu- tacture of iron by the actual introduction of metallic zinc in some one or other of the stages of its manufacture, such as in the puddling furnace. What the nature of the action of the zinc is, we are not yet able to say; all we as yet know is, that, so far from being prejudicial to the quality of the iron, it appears to have rather an improving effect; and that to such an extent as to cause us to desire that the subject may receive the attention of some of our intelligent iron manufacturers, so as to put the matter to the test of actual experiment in the puddling furnace, or any other stage of the pro- cess such as may appear to promise the best results. I may name a curious corroborative fact, that tlie strongest cast-iron made in Belgi- um, and selected for the casting of guns, is made from an iron ore in which the ore of zinc forms a considerable portion. Whether the superiority of this iron is due to the presence of zinc is a question ; but the result of the before named experiments tend to lead to the supposition that such may be the case. The small town of Stolberg, about four miles from Eschweiler, is a centre of great manufacturing activity. Perhaps the most interesting establishment for strangers are those for producing zinc from calamine. The best mines belong to the company of the Marquis de Sessenaye, a French gentleman, who established here zinc works on a large scale, in which the following system is adopted: — A chimney of considerable width, but of moderate height, stands in the centre of each batch of furnaces. In the middle, immediately adjoining the chimney, are two roasting furnaces, in which the ore is calcined. To the right and left of these are two pairs of reducing furnaces, or rather two large reterberatory furnaces, which are charged in the middle from above, and which are open at the side towards the gangways. In the space between the middle, or firing place, and these openings, are placed a series of retorts of fire-proof clay, of elliptical shape, into which moveable necks are inserted, that communicate with short perpendicular pipes, which fit into holes in the earthen- plate, under which openings like an ash-pot are constructed. The ore having been well calcined in the roasting furnaces, are turned from a carbonate into an oxide of zinc, is first powdered. The oxide is then placed in the retorts, or muffles, as they are called, and the furnaces are carefully closed with clay, and highly heated to throw off the oxygen in the shape of gas. One result of the great heat in this process is that a large proportion of the metal escapes with the oxygen, which finds its way through the neck of the retort and down the tube connected with it, where the reduced metal falls in small globular particles. The metal thus deposited is washed from the refuse that falls from it> and is melted in furnaces placed at the extremity of the reverberatory furnaces. The heat of these serve to melt the zinc that it may cast into thin blocks for rolling into sheets. The production of these works is estimated at 10 tons per dieno^ For this, a consumption of seven times the weight of coal is required. ZIRCORN. See HYAaNxn and Lapidary. ZIRCONIA, is a rare earth, extracted from the minerals zircon and hyacinth; it is an oxide of zirconium, a substance possessing externally none of the metallic characters, but resembling rather charcoal powder, which burns briskly, and almost with explosive Tiolence. IX THE END. . ' • ' J . * . ' . t > 4 < • I • • t « • . i >se^amms»0mim \ ' z CIECDLATLS FOR 1 WEEK COLUMBIA UNIVERSITY LIBRARIES This book is due on the date indicated below, or at the expiration of a definite period after the date of borrowing, as provided by the library rules or by special arrangement with the Librarian in charge. DATE BORROWED DATE DUE DATE BORROWED DATE DUE • 1 i - cae (7A7) Mioo is> ^jAdHl^^ ^bv 1^ ^,^ fHfPIHD U.A. I 1/ ^^e* Andrew *°d Min^/^^^ts, ^Manufactures, .SlBCUUrtS FOR 1 Wrr 4j-s MAY, m '^*?^'^^--'*'^r'*2|\^.|":'^^^^^ . ^'S-!c^f. ' ^ ^. - -?y». '#.. -'IX tj. ■?J* ' c-fe «3fi??^ Mt ^ / v^ t-t- .rXA-:; 4'.'--H^ ^ -^A^^^a : ?•«:■ ^^ . i-« -^ "'. " "?.* ' • ' T : i . ^ T ^ r :^' Ir J. 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