FMEFAVE^ 
 
 The favourable reception given by the 
 public, to an Essa^ on the Warming of Mills 
 and other Buildings hy Steam^ which I pub¬ 
 lished in 1807 *, and the many additional 
 facts on the subject, which, since that 
 period, have been determined, and the 
 further application of this agent to drying 
 as well as heating, in various processes in 
 calico-printing and odier manufactures, 
 have induced me to think of publishing 
 an enlarged edition of that Essay. 
 
 Reflecting on this subject, and consider¬ 
 ing the materials I had collected on other 
 practical applications of heat, it occurred 
 to me, that I might extend my plan to a 
 series of Essays on the Economy of Fuel and 
 Management of Heat. 
 
 • For an account of this Pamphlet, see Philosophical Magazine, 
 Nicholson’s Philosophical Journal, Monthly Magazine, and various 
 other periodical publications for 1’808. 
 
 a 
 
 8320 
 
PREFACE. 
 
 iv 
 
 In order to clear the way for these prac¬ 
 tical inquiries, it seemed proper, to give 
 such a view of some of the principal laws 
 which regulate the phenomena of heat, as 
 would, by the help of references, enable the 
 reader the better to tmderstand the nature 
 of the facts and observations which.-would 
 occur, in the. subsequent parts-bf these in¬ 
 quiries. To this, purpose, I have aceord- 
 ingly devoted the first part of this .Essay. 
 
 • Originally, I had no intention to make 
 this introductory part’ so large as it now 
 is, but in pursuing the subjects which it 
 contains, it appeared to me, that to em¬ 
 brace the objects of my intention, it could 
 not easily be made less. It would, per¬ 
 haps, not conduce to my credit as a writer, 
 were I to tell the trouble this part has cost 
 me; and, rfter all my labour, I fear it will 
 be thought by many, a mere, compilation. 
 But I -was rnore an^pus to make, a useful 
 than an elegant book, .and, therefore, have 
 attempted, in a small compass, to bring 
 into vievsr, all the practical knowledge that 
 I could find on subjects, which I thought 
 
PREFACE. 
 
 could be beneficial to a valuable class of 
 men, whose time, being otherwise, fully 
 occupied^ have neither' Irisure, opportunity, 
 nor inclination, to search into numerous, 
 and often: costly volumes. If I have suc¬ 
 ceeded in this intention, my labour has 
 not been in vain. Nor will general readers, 
 I trust, deem this part altogether unworthy 
 their notice,' having : endeavoured in it, to 
 give a concise view of the. late .important 
 discoveries made by Professor Leslie and 
 others, respecting, heat. 
 
 The opportunities which I have had, of 
 conversing and corresponding with several 
 of these writers, as well , as-.with other men 
 of science, .whose pursuits have been more 
 immediately practical, I have endeavoured 
 to turn to the advantage of the. reader. 
 In the “ Additions and Corrections,” I 
 have studied to correct such errors or 
 mistakes as' have occurred in die course 
 of this Essay. 
 
 The advantages which this island enjoys 
 over other countries, from the abundance 
 
PREFACE. 
 
 vl 
 
 of coal, are too well known to require to 
 be here enumerated. But in many other 
 things we labour under much disadvantage, 
 which should stimulate us to cherish this 
 superiority which we enjoy over the nations 
 on the Continent of Europe. The economy 
 of fuel becomes a subject of increasing 
 importance, from the' increasing price of 
 labour, which would require exertion to 
 counteract its effects on our commerce and 
 manufactures. Every attempt, therefore, 
 to save fuel, merits attention j and the 
 subject opens a wide and important field 
 for investigadon. 
 
 It is not the saving only of fuel which 
 merits attention, but its safe^ easy^ and 
 healthful application to the various pur¬ 
 poses of life. 
 
 .The recent destruction by fire, of St. 
 James’s Palace, and of the two largest 
 Theatres in - the kingdom, has directed 
 much of the public attention to the ren¬ 
 dering of buildings less subject to so 
 dreadful a calamity. In this important 
 
respect, no means of heating buildings has 
 yet been devised, so good as that by steam, 
 and from its novelty, none is yet so parr 
 tially known or understood. I have, there¬ 
 fore, been induced to make it the princi¬ 
 pal subject of this Essay. 
 
 It consists of Three Parts, the first of 
 these I have already mentioned. The 
 Second Part relates to the application of 
 steam to the heating of buildings of vari¬ 
 ous descriptions, such as dwelling-houses, 
 manufactories, arid public buildings. The 
 Third Part treats of the application of this 
 agent to drying of goods, as well as to 
 further naatters relative to heating. Its 
 excellent efiect in preserving, brilliancy of 
 colour, in drying goods, is there proved 
 by strong facts;—a consideration of much 
 importance in many of our manufactures. 
 
 I must crave the indulgence of the pub¬ 
 lic, for any want of tmity, and other im¬ 
 perfections, which will too readily appear 
 in the whole of this Essay. I have to 
 plead, that it was written at many differ- 
 
PREFACE. 
 
 vili 
 
 ent and distant intervals, occasioned by 
 interruptions from professional engage¬ 
 ments, as well as from , other and more 
 irksome causes, with a detail of which I 
 shall not trouble die reader. 
 
 With regard to the subject of heating 
 by steam, I beg leave here further to re¬ 
 peat the Preface to the Publication to which 
 allusion is made at the beginning of this 
 introduction. 
 
 “ In a country like Britai -., where man¬ 
 ufactures ai'e more generally collected and 
 combined in large establishments, than 
 dispersed through individual dwellings; 
 the production and diffusion of the warmth 
 necessary for the health and comfort of 
 the workmen, as well as for the prosecu¬ 
 tion of the different processes, become 
 objects of the first national importance. 
 
 “ The excessive expense of insurance, 
 arising from the combustible nature of the 
 materials of the cotton manufacture in par¬ 
 ticular; the great difficulty of retrieving the 
 
PR-FBACE; 
 
 ix 
 
 injury resulting to a well established busi¬ 
 ness, from the accidental destruction of 
 machinery; and the frequent alarms from 
 fire, in our powder-mills, arsenals, and 
 dock-yards, furnish the strongest economi¬ 
 cal, as well as political recomniendations; 
 for the more general employment of steam 
 for the purpose of warnilhg bitildings; 
 
 “ The very, limited degree in which 
 steam has yet been applied to this pur¬ 
 pose, might surprise us, did we not recol¬ 
 lect, that the steam-engine itself, although 
 known, perhaps, even before the time of 
 the celebrated Marquis of Worcester, 
 has only, within a very few years, by the 
 ingenious improvements of Mr, Watt, 
 been extensively introduced. The fre-. 
 quent and varioususe, of steam, , to which 
 Mr. Watt’s improvements have given 
 rise, in different departments of manufac¬ 
 ture, have furnished accidental results of 
 great value, which ai'e frequently little 
 known to the merely scientific inquirer. 
 
PREFACE. 
 
 “ THe observations which the Author 
 has been enabled to make, on various con¬ 
 trivances throughout the kingdom, for 
 heating by - steam, modified by his own 
 experience, have led him to believe, that 
 the following remarks on this important 
 subject, would not be altogether undeserv¬ 
 ing the notice of the public. 
 
 “ He, however, lays no claim to origin¬ 
 ality, nor does he pretend to give informa¬ 
 tion to men of science, his object is merely 
 to make such a collection of facts, as may 
 be useful to those who wish to put in 
 practice the warming of buildings by 
 
 “ In making this collection, he has been 
 much indebted to the assistance of some 
 friends, without the aid of whose ingenu¬ 
 ity and experience, his readers would have 
 had still more reason to lament its defi¬ 
 ciency. 
 
 “ Those who are most qualified to esti¬ 
 mate the importance of such investigation, 
 
PREFACE. 
 
 s:i 
 
 can best appreciate their difficulty, and 
 will, most readily, and candidly, pardon 
 the unavoidable imperfection o£ this at¬ 
 tempt; the chief object of which, is less to 
 satisfy curiosity, than to direct the atten¬ 
 tion of the; public', to the farther prosecu¬ 
 tion of an inquiry, not less curious: than 
 useful.” 
 
 I shall now proceed to give an account 
 of the origin and progress of this applica^ 
 tion of steam, 
 
 Jn Acc/omt. of the. Origin and Progress of the. 
 Application of Steam^ to. the purpose of Heatr. 
 ing Bi tidings. 
 
 In the Philosophical Transactions for the 
 year 1745^ Colonel William Cook suggests 
 the idea of warming rooms by steam. But 
 it does not appear that he ever attempted 
 to reduce it to practice. And although 
 Count Rumford, in the third-number of 
 the Journals of the Royal Institution, men¬ 
 tions, that “ this scheme- has frequently 
 “ been put in practice with success, in this 
 “ country, as well as on the Continent,” 
 b ■ 
 
I have not been able to learn, that any 
 thing of importance was done, previously 
 to the use of steam in warming cotton- 
 mills* 
 
 It is natural to suppose, that Mr. Watt’s 
 attention to other applications of steam, 
 would lead him to the consideration of the 
 particular subject of heating buildings. 
 Such was indeed the case. The period at 
 which he used steam for warming the 
 room in which he commonly wrote, was 
 1784, or 5, probably the winter between 
 these two years. The room was about 18 
 feet long, by 14 feet wide, and feet 
 high; and the apparatus consisted of a 
 box, or heater, made of two side-plates of 
 tinned iron, about 3i feet long, by 2i wide, 
 kept at the distance of an inch asunder, by 
 means of stays, and joined round the edges 
 by other tin-plates. This box was placed 
 upon its edge, near the floor of the room, 
 and. furnished with a cock to let out the 
 air, and with , a pipe, proceeding from its 
 
 A patent for heating By steath tras granted to John Hoyle, dated 7th 
 Wyi 1791; and to Joseph Green, dated 9th December, 179S. 
 
PREFACE. 
 
 XIU 
 
 lower edge to a boiler in an under apart¬ 
 ment, which pipe served , to convey the 
 steam, and return the water. , The effect 
 produced by ,this apparatus, was less than 
 Mr. Watt had calculated, which, perhaps, 
 may now be .explained by Professor Leslie s 
 experiments .on the heat transmitted by 
 polished surfaces. 
 
 Mr. Boulton heated a room in his man¬ 
 ufactory by steam, soon after this time; 
 but the very infirm state of his health at 
 this moment, prevents me from obtaining 
 accurate information concerning it He, 
 however, heated his bath by steam, a few 
 years later, I believe about the year 1789, 
 which he continued to do from that period, 
 until a very short time ago. 
 
 Towards the end of the year 1794, he 
 assisted the late Marquis of Lansdown, to 
 improve an apparatus, erected by a Mr. 
 Green, for warming his library, by means 
 of air heated by steaui; but the use of it 
 was afterwards abandoned, owing, I be- 
 
 • This w.as written previonriy to Mr. Boulton’s death. 
 
51V 
 
 PREFACE. 
 
 -lieve, to some defect ia the pipes or joints. 
 About a twelvemonth later, in the winter 
 of 1795-6, Mr. Boulton directed the erec¬ 
 tion of a similar apparatus, for his friend 
 Dr. Withering’s library, which, in point 
 of;.heating, answered perfectly; but the 
 pipes being ^nade of copper, and soft sol¬ 
 dered in some places, the smell of the 
 solder was rather unpleasant to the Doctor, 
 who was then in an infirm state of health 
 with diseased lungs. The apparatus was, 
 k consequence, removed to Soho, where 
 Mr. Botdton proposed erecting it in his 
 own house, in which he was making al¬ 
 terations about this time, and had it in 
 view, to heat every. room in the house ^by 
 steam. A boiler was put up for that pur¬ 
 pose, m one of the ceUaxs, but some cir- 
 cmnstances occurred, to prevent his con- 
 tinuing the plan. The subject, however, 
 underwent frequent discussions, and the 
 diSerent modes of efiecting it, were amply 
 considered by Messrs. Boulton and Watt, 
 as was known to many of their friends, 
 no secret having been made, either of cal¬ 
 culations of surface, or of the modes of 
 applykg them. 
 
PREFACE. XV 
 
 About the end of the year 1799, Mr. 
 Lee of Manchester, having a large increase 
 of his cbtton-rmill in view, consulted with 
 Messrs. Boulton and Watt, relative to the 
 best mode of heating it by steam; and, in 
 the course of the subsequent year, he 
 erected his present apparatus of cast-iron 
 pipes, acting also as supports to the floor, 
 which answered perfectly, and was, both 
 in'point of the materiais used, and of the 
 construction adopted, as far as I know, the 
 first of the kind.. I may add, that though 
 the construction has been frequently inii- 
 tated by others, I have never heard of any 
 material improvement having been made 
 upon it., from that period, many appara¬ 
 tus were constructed, by them, in some of 
 which, applied to old buildings, the pipes 
 were conducted horizontally through the 
 rooms, with other variations of little im¬ 
 portance. 
 
 It may not be improper here to add, the 
 vats, &c. of the dye-house of Messrs. 
 Wormauld '& Gott, of Leeds, were heated 
 by steam, under the direction of Messrs, 
 
xvi 
 
 PREFACE. 
 
 Boulton & Watt, in the year 1799. The 
 apparatus was planned in August of that 
 year, and set to work either in the course 
 of it, or early in the succeeding one. The 
 history of that establishment has been 
 very incorrectly given, in the Journals of 
 the Royal Institution, for iSOl. 
 
 The merit of the first application of 
 steam, to the heating of buildings in Scot¬ 
 land, belongs to Mr. Snodgrass. He in¬ 
 troduced it* into the cotton-work, which 
 Messrs., Dale & M‘Intosh established on 
 the banks of the Spey f. 
 
 Soon after this period, Mr. Houldsworth 
 of Glasgow, used it with great success. 
 His example has been followed by several 
 other respectable cotton-spinners. 
 
 Steam was soon afterwards applied to 
 warm buildings, appropriated to the pur¬ 
 poses of calico-printing. Mr. Richard 
 
 • In the year 1799, and, there is reason to think, without the know¬ 
 ledge of what had been done in England. 
 
 + See Philosophical Magazine for March, 1807. 
 
PREFACE. 
 
 xvii 
 
 Gillespie, in his calico-works at Anderston, 
 was induced very early to use it in his 
 warehouse for finished goods, and has ' 
 since been gradually extending it through 
 other parts of his works*. It has also 
 been adopted by some calico-printers in 
 England. 
 
 Messrs. W. Stirling & Sons are at present 
 getting steam apparatus fitted up for their 
 extensive calico-printing works at Cordale, 
 
 In Ireland, Messrs. Orr have introduced 
 it at their works, at Stratford upon Slainy. 
 It is also gradually finding its way into 
 the cotton-mills in that kingdom. 
 
 Messrs. Oakley & Co. cabinet-makers, 
 London, have heated their premises by 
 Steam; and Messrs. James Ballantyne & 
 Co. have applied it to the heating of their 
 printing-ofiice in Edinburgh. 
 
 * In the introduction to the Third Part of this Essay, there is a 
 narrative respecting the application of steam to the purpose of drymi. 
 
TABLE OF CONTENTS. 
 
,#att jfirst 
 
 ON THE 
 
 EFFECTS OF HEAT, 
 
 MEANS OF MEASURING IT, 
 
 FUEL, &c. 
 
 SECTION I. 
 
 1. Before proceeding'to the more prac¬ 
 tical parts of the economy of fuel, in order 
 to establish our inquiries on solid grounds, 
 it will be proper here, to take a view of 
 some of the principal laws which regulate 
 the phenomena of heat. 
 
 . A 
 
2 
 
 EFFECTS OF HEAT. 
 
 The most eminent philosophers of the 
 present age, are not yet agreed respecting 
 the nature of heat, nor can any of them yet 
 give to a plain inquirer a satisfactory an¬ 
 swer to this simple question. What is heat? 
 While some consider it as merely a state or 
 condition of which all bodies are susceptible; 
 others conceive that heat is a material sub¬ 
 stance—raxi elastic fluid, extremely subtile 
 and active. 
 
 I shall not take up the reader’s time, 
 by attempting to investigate the merits of 
 those opinions, since it is of no consequence 
 to our present purpose, which of the parties 
 is in the right. 
 
 But although we may not be able to 
 comprehend the nature of heat, we may 
 amve at the knowledge of many of its 
 ^ects, and so classify and arrange these, 
 as to adapt them to many ustful purposes 
 in common life. 
 
EFFECTS OF HEAT. 
 
 OF HEAT. 
 
 2. The term Aeai, as used in common 
 language, is ambiguous, being applied to 
 express either a certain sensation.^ or the ex¬ 
 ternal cause which excites that sensation. 
 It is in this last sense only, that we are at 
 present to consider it; and to this meaning 
 of the term heat., the authors of the New' 
 French Chemical Nomenclature, have given 
 the definite name of caloric *. 
 
 3. “ When all surrounding bodies are of 
 one temperature, then the heat attached to 
 them is in a quiescent state; the absolute 
 quantities of heat in any two bodies, in 
 this case, are not equal, whether we take 
 
 • “ The term caloric has been adopted in the New Nomenclature, to 
 avoid that ambiguity and misconception which might, it is said, arise 
 from employing- the same term to express a substance, and the sensa¬ 
 tion produced by the action of that substance. By the same mode of 
 reasoning, all the sutilantha should be changed, in any language that 
 has similar -peril. But suppose the argument, for change, in the pre¬ 
 sent instance, to have full force in some languages, it has little or none 
 with regard to the English, which employs the word loarmth to express 
 the sensation occasioned by heat. I shall, however, use the terms heat 
 and caloric indifferently.” 
 
 Tilheh's Phileiophieal Magazine, vol. 8. p. 71. 
 
4 
 
 EFFECTS OF HEAT. 
 
 the bodies of equal weights, or of equal 
 bulks. Each kind of matter has its peculiar 
 affinity for heat, by which it requires a 
 certain portion of the fluid, in order to be 
 in equilibrium with other bodies at a cer¬ 
 tain temperature Thus, when the heat 
 of a room is increased, the various bodies 
 contained in it will attract and retain dif¬ 
 ferent quantities of heat. This property 
 seems to indicate the materiality of caloric, 
 since, though in a quiescent state, it exists 
 in bodies in difierent proportions, modified 
 neither by their density nor form, but by 
 some innate and peculiar force of attraction, 
 resembling chemical affinity. To express 
 this faculty, the term capacity for heat was 
 invented, and employed by the British 
 philosophers; the name specific caloric being 
 used for the same purpose, by ^ose on the 
 Continent. 
 
 However various the capacities of bodies 
 for heat may be, yet, in consequence of the 
 perfect elasticity of this power, it will 
 speedily acquire the same tension in them 
 
 * Dalton’s Chemical Philosophy, p. 2. 
 
EFFECTS OF HEAT. 
 
 5 
 
 all; or, like a number of tubes of different 
 magnitudes, but narrow apertures, plunged 
 into the same vessel of water, it will soon 
 stand in each at the same height or level, 
 though the absolute quantity in them be 
 very different. Now, it must evidently be 
 a desirable object, with the philosopher, 
 to obtain some means of estimating this 
 tension, or height, or degree of tempera¬ 
 ture, as it is technically termed. • 
 
 Of Tltermometers. 
 
 4. The thermometer was invented early 
 in the 17th century, but, like many other 
 useful contrivances, its real author has 
 never been ascertained. The first form of 
 this instrument was the air thermometer^ 
 The air was confined in a tube by means 
 of some coloured liquor, and the liquor 
 rose or fell in. the tube, accordingly as the 
 air became expanded or condensed. It was 
 found, however, to be very defective. The 
 expansion of spirit of wine was next used, 
 but still thermometers had a great defect; 
 the scale did not commence at any Jixed 
 
6 
 
 EFFECTS OF HEAT. 
 
 point. While they laboured under this 
 disadvantage, they could not be of general 
 use. 
 
 The subject which next drew the atten¬ 
 tion of philosophers, was to obtain some 
 fixed unalterable points, by which a deter¬ 
 minate scale might be formed, so that all 
 thermometers might be accurately adjusted 
 to one standard. These important points, 
 on which the accuracy and value of the 
 thermometer depends, although previously 
 discovered by Dr. Hooke seem first to 
 have been practically applied by Sir Isaac 
 Newton. He chose, as fixed, those points 
 at which water freezes and bods; the very 
 points which the experiments of succeeding 
 philosophers have determined to be the 
 most fixed and convenient. Sir Isaac 
 Newton used lintseed oil in his thermom¬ 
 eter, which was constructed in 1701. 
 
 5. Oil, however, was found to have 
 many imperfections. At length a different 
 
 • Dr. Robert Hooke discovered the pennaneccy of the temperature 
 of freezing in 1664, and of boiling water in 1684. 
 
EFFECTS OF HEAT. 
 
 fluid was proposed, by which thermometers 
 could be made free from most of the defects 
 alluded to. This fluid was mercury, and 
 seems first to have occurred to Dr. Halley, 
 about the end of the 17th century, but was 
 not adopted by him, on account of its hav¬ 
 ing less expansibility than the other fluids 
 then in use for thermometers. The honour 
 of this invention is commordy given to 
 Fahrenheit of Amsterdam, who presented 
 an account of it to the Royal Society of 
 London, in 1724. 
 
 6. Fahrenheit’s thermometer consists of 
 a slender cylindrical tube, and a small bulb. 
 To the side of the tube is annexed a scale 
 which Fahrenheit divided into 600 equal 
 parts,, beginning with that of the severe 
 cold which he had observed in Iceland, in 
 1709, or that produced by surrounding 
 the bulb of the thermometer with a mix¬ 
 ture of snow with sal-ainoniac, or with 
 sea-salt. The point at which mercury be¬ 
 gins to boil, he made the other limit of his 
 scale. By trials, he found that the mercury 
 stood at 32“ on his scale, when snow or 
 
8 
 
 EFFECTS OF HEAT. 
 
 ice just begins to thaw, which was, there¬ 
 fore, called the freezing point. When the 
 tube was immersed in boiling water, the 
 mercury rose to 212°, which was, therefore, 
 denominated the boiling point.^ and is just 
 180° above the freezing point. 
 
 7. But the present method of making 
 these thermometers, is to immerse the bulb 
 in melting ice or snow, and mark the place 
 where the mercury stands with the num¬ 
 ber 32°, then immerge it in boiling water, 
 and again mark the place where the mer¬ 
 cury, stands in the tube, which indicates 
 the position of 212°. Dividing, therefore, 
 the intermediate space into 180 equal parts, 
 will giye the scale of the thermometer, and 
 which may afterwards be continued upward 
 and downward at pleasure. 
 
 8. These fixed points are now universally 
 chosen for adjusting thermometers to a 
 scale, but it is well known that the point 
 at which water boils is not invariable. It 
 varies some degrees, according to the weight 
 and temperature of the atmosphere. 
 
EFFECTS OF HEAT. 
 
 9. In order, therefore, to insure uni¬ 
 formity in the construction of thermom¬ 
 eters, it is now agreed, that the bulb 
 of the tube be suspended in the steam 
 when the water boils violently, the barom¬ 
 eter* standing at 30 English inches, which 
 is its mean height round London, and the 
 temperature of the atmosphere 55° f. 
 
 10. Fahrenheit’s thermometer is now 
 universally used in this kingdom. See 
 Fig.i: 
 
 The centigrade thermometer, or that of 
 France, since the Revolution, places Zero, 
 or 0, at the freezing point, and divides the 
 range between it and the boiling point 
 into, 100°. This has been long used in 
 
 • I suppose the reader to he previously acquainted with the doctrine 
 ef the frtssarc of the atmoifihcre, and the construction of the barometn'. 
 If not, as it is necessary to the right understanding of the following 
 parts of this Essay, I beg leave to refer to Gregory’s Mechanics, voL 2. 
 p. 112, or almost any other of the elementary Treatises on Natural 
 Philosophy. 
 
 f See the Report of the Committee for adjusting Thermometers, 
 Philosophical Transactions, vol. LXVII. 
 
 B 
 
10 . EFFECTS OF HEAT. 
 
 Sweden, under the tide of Celsius’s ther¬ 
 mometer. See Fig. 2, 
 
 11. Reaumur’s thermometer, which was 
 formerly used in France, divides the space 
 between the freezing and the boiling of 
 water, into 80 degrees, and places the 
 Zero at the freezing point. Fig. 2, 
 
 12. Mr. Murray has suggested a scale 
 which, he conceives, wotdd be much more 
 convenient than that of Fahrenheit. He 
 uses, as fixed points, those of the freezing 
 and boiling of mercury, and divides the 
 intermediate space into one thousand 
 parts, or degrees *. See Fig. 3. 
 
 13. The expansion which is observed in 
 a mercurial thermometer, is, in reality, 
 only the difierence of expansions of mer¬ 
 cury and of glass. 
 
 14. It has long been supposed, that the 
 egual divisions on Fahrenheit’s scale, did 
 
 Murray’s Chemistry, voL i. p. 15S. 
 
EFF-ECTS OF HEAT'.' 11 
 
 not point out the real equal increments 
 (or degrees of equal increase) of tempera¬ 
 ture. This circumstance was not over¬ 
 looked by Dr. Black, who illustrates it in 
 the following manner: “ If a string be 
 stretched, by suspending a nioderate 
 weight to it, and we add one pound to 
 that weight, we shall make it a little 
 longer j but by adding a second pound, 
 we shall not add as much more to the 
 length of the string as the first pound 
 added, nor will a third pound produce so 
 much effect as the second pound. In like 
 manner, we can imagine, that when a 
 thermometer receives a series of equal ad¬ 
 ditions to its heat, these may not produce 
 equal increments of expansion; and, there¬ 
 fore, that equal increments of expansion 
 may require for their production, incre¬ 
 ments of heat, very unequal among them¬ 
 selves. This question has been over¬ 
 looked, or little attended to, by some of 
 the principal writers on thermometers. It 
 does not appear to have occurred to Dr. 
 Boerhaave, and Dr. Martin gives very little 
 attention to it. I began to attend to it, 
 
12 EFFECTS OF HEAT. 
 
 and made an experiment to decide it in 
 the year 1Y60, and did not then know that 
 others' had thought of it; but I soon 
 learned, that Boyle, Renaldini of Padua, 
 Wolfius, Dr.- Halley, Sir Isaac Newton, 
 and Dr. Brook Taylor, had severally given, 
 their opinions or doubts concerning this 
 question*.” 
 
 The result, however, of. Dr. Black’s 
 inquiry was, “ that equal additions, or 
 abstractions of heat, produced equal varia¬ 
 tions of bulk in the liquor of the thermom¬ 
 eters employed by him, and, therefore, 
 that the scale of expansion was also a scale 
 of heat f, or, at least, that, there was but 
 " a little deviation from the exact propor¬ 
 tion^’ 
 
 “ M. De Luc,” says Mr. Dalton, “ found 
 that in mixing equal weights of water, at 
 the freezing and boiling temperatures, 32* 
 and 212°, the mixture indicated nearly 
 
 ■ • Vide Black’s Lectures, vol. i. p. 56 and 57. 
 
 f Black’s Lectures, vc!. i. Preface, p. axxix. 
 
EFFECTS OF HEAT, 
 
 13 
 
 119® of Fahrenheit’s thermometer, but the 
 numerical mendj. or average, is 122°. If 
 he had mixed equal bulks of water at 32® 
 and 212°, he would have found a mean of 
 115V’ 
 
 15. “ It is not improbable, that the true 
 mean temperature between 32° and 212°, 
 may be as low as 110° of Fahrenheit*”. 
 
 We are indebted to Mi'. Dalton, for 
 farther investigating this intricate subject, 
 and he has formed a. scale which, he con¬ 
 ceives, will correspond with the increments 
 of heat; and, as this is an important part 
 of our subject, I shall here give some 
 extracts with relation .to it, from his late 
 valuable publication. 
 
 16. “ In the present imperfect mode of 
 estimating temperature, the equable expan-- 
 sion of mercury is adopted as a scale for 
 its measure. This cannot be correct, for 
 two reasons: 1st, The mixture of water of 
 
 .* Dalton’s Chemical Philosophy, p. 7. 
 
14 EFFECTS OF HEAT. 
 
 different temperatures, is always below the 
 mean by the mercurial thermometer; for 
 instance, water of 32° and 212° being 
 nuxed, gives 119° by the thermometer; 
 whereas, it appears, from the preceding 
 remarks, that the temperature of such 
 mixture ought to be formd above the 
 mean 120°. 2d, Mercury appears, by the 
 most recent experiments, to expand by the 
 same law as water, namely, as the square 
 of the temperature from the point of 
 greatest density. The apparently equal ex¬ 
 pansion of merctuy, arises from bur taking 
 a small portion of the scale of expansion, 
 and that at some distance from the freez¬ 
 ing point of the liqvsid. 
 
 17. “ From what has been remarked, it 
 appears, that we have not yet any mode, 
 easily practicable, for ascertaining what is 
 the true mean between any two tempera¬ 
 tures, as those of freezing and boiling 
 water; nor any thermometer which can 
 be considered as approximating nearly to 
 accuracy. 
 
EFFECTS OF HEAT. 
 
 15 
 
 18. “ Heat is a very important agent in 
 nature; it cannot be doubted, chat so active 
 a principle must be subject to general laws.. 
 If the phenomena indicate otherwise, it is 
 because we do not take a sufficiently com¬ 
 prehensive view of them. Philosophers 
 have sought, but in vain, for a body that 
 should expand uniformly, or in arithmeti¬ 
 cal progression, by equal increments of 
 heat; liquids have been tried, and found 
 to expand unequally; all of them expands 
 ing more in the higher temperatures than 
 in the lower, but no two exactly alike. 
 Mercury has appeared to have the least 
 variation, or approaches nearest to uniform 
 expansion, and on that and other accounts, 
 has been generally preferred, in the con¬ 
 struction of thennometers. 
 
 19. “ Some time ago, it occurred to 
 me as probable, that water and mercury, 
 notwithstanding their apparent diversity, 
 actually expand by the same law, and 
 that the quantity of expansion is as the 
 square of the temperadire, from their re¬ 
 spective freezing points. Water very 
 
16 
 
 EFFECTS OF HEAT. 
 
 nearly accords with this law, according to 
 the present scale of temperature, and the 
 Jitde deviation observable, is exactly of 
 the sort that ought to exist, from the 
 knovfs, error of the equal division of the 
 mercurial scale. By prosecuting this in- 
 quifyj I found that the mercuri^ and 
 water scales, divided according to the 
 principle just mentioned, would perfectly 
 accord, as far as they were comparable, 
 and that the law will probably extend to 
 all other pure liquids, but not to hetero¬ 
 genous compounds, as liquid solutions of 
 
 20. “ However, it now appears, that the 
 force of steam, in contact with water, in¬ 
 creases ACCURATELY in geometrical pro¬ 
 gression, to equal increments of tempera¬ 
 ture, -provided those increments are mea¬ 
 sured by a thermometer of water or mer¬ 
 cury, the scales of which are divided 
 according to the above-mentioned law. 
 
 • Dalton’s Chemical Philosophy, p. 8—II. 
 
EFFECTS OF HEAT. 
 
 17 
 
 21. “ The force of steam ha,ving been 
 found to vary by the above law, it was 
 natural to expect that of air to do the same; 
 for, air (meaning any permanently elastic 
 fluid) and steam are essentially the same, 
 difiering only in. certain modifications. 
 Accordingly, it was found upon trial, that 
 air expands in geometrical progression to 
 equal increments of temperature, measured 
 as above. Steam detached from water, by 
 which it is rendered incapable of increase 
 or diminution in quantity, was found, by 
 Gay Lussac, to have tbe same quantity of 
 expansion as the permanently elastic fluids. 
 J had formerly conjectured that air expands 
 as the cube of the temperature from absolute 
 privation, as hinted in the essay above- 
 mentioned; but I am now obliged to 
 abandon that conjecture. 
 
 22. “ The union of so many analogies, 
 in favour of the preceding hypothesis of 
 temperature, is almost suflicient to establish 
 it; but one remarkable trait of temperature, 
 derived from experiments on the heating 
 and cooling of bodies, which does not ac- 
 
 C 
 
18 
 
 EFFECTS OF HEAT. 
 
 cord with the received scale, and which, 
 nevertheless, claims special consideration, 
 is, that a body in cooling loses heat in propor¬ 
 tion to its excess of temperature above that of 
 the cooling medium', or that the temperature 
 descends in geometrical progression in 
 equal moments of time. Thus, if a body 
 were 1000° above the medium; the times 
 in cooling from 1000° to 100, from 100 
 to 10, and from 10 to 1°, ought all to be 
 the same. This, though nearly, is not 
 accurately true, if we adopt the common 
 scale, as is well known; the times in the 
 lower intervals of temperature are found 
 longer than in the upper; but the new 
 scale proposed, by shortening the lower 
 degrees, and lengthening the higher, is 
 found perfectly according to this remark¬ 
 able law of heat. 
 
 23. “ Temperature then will be found 
 to have four most remarkable analogies 
 to support it. 
 
 “ 1st. All pure homogenous liquids, as 
 water and mercury, expand from the point 
 of their congelation, or greatest density, a 
 
EFFECTS OF HEAT. 19 
 
 quantity always as the square of the tem¬ 
 perature from that point. 
 
 “ 2. The force of steam from pure 
 liquids, ‘ias water, ether, &c. constitutes a 
 geometrical progression to increments of 
 temperature in arithmetical progression. 
 
 “ 3. The expansion of permanent elastic 
 fluids, is in geometrical progression to 
 equal increments of temperature. 
 
 “ 4. The refrigeration of bodies is in 
 geometrical progression in equal incre¬ 
 ments of time. 
 
 “ A mercurial thermometer graduated 
 according to this principle, will differ from 
 the ordinary one with equidifferential 
 scale, by having its lower degrees smaller, 
 and the upper ones larger; the mean be¬ 
 tween freezing and boiling water, or 122° 
 on the'new scale, will be found about 110° 
 on the old one.—The following table ex¬ 
 hibits the numerical calculations illustra¬ 
 tive of the principles inculcated above 
 
 * Ealton’s Chemical Philosophy; p. 11—14. 
 
EFFECTS OF HEAT. 
 
 21 
 
 Explanation of the Tahk. 
 
 25. Column I. contains the degrees of 
 temperature, of which there are supposed 
 to be 180, between freezing and boiling 
 water, according to Fahrenheit. By com¬ 
 paring' this column with the II. the cor¬ 
 respondences of Mr. Dalton’s new scale and 
 the common one are perceived; the greatest 
 difference between 32° and 212°, is ob¬ 
 servable at 122° of the new scale, which 
 agrees with 110° of the old, the difference 
 being 12°; but below 32° and above 212* 
 the differences become more remarkable. 
 
 The first number in the column, —175“ 
 denotes the point at which mercury freezes, 
 hitherto marked -^40°. 
 
 By vietying column II. along with the I. 
 the quantity of the supposed error in the 
 common iscale may be perceived; and any 
 observations on the old thermometer may 
 be reduced to the new. See Fig. 1. 
 
 Column II. contains the common Fah¬ 
 renheit’s scale. 
 
EFFECTS OF HEAT. 
 
 CoItitdii ni. contains a series of numbers 
 in geometrical progression, representing 
 the expansion of air, or elastic fluids. 
 
 Column IV. contains the squares of the 
 arithmetical series, 1,2, 3, &c., representing 
 the expansion of water by equal intervals 
 of temperature. 
 
 Column V. contains the force of aque¬ 
 ous vapours in contact with water, ex¬ 
 pressed in inches of mercury, at the re¬ 
 spective temperatures. 
 
 26. On the construction hitherto de¬ 
 scribed, the thermometer is necessarily 
 very limited in its application. When 
 made with alcohol, or spirit of wine, it 
 maybe said, indeed, to measure the greatest 
 degrees of cold with which we are ac¬ 
 quainted; but even the mercurial ther¬ 
 mometer measures no higher than 400 
 degrees above boiling water, by Fahren¬ 
 heit’s scale, or about 250 degrees by Mr. 
 Dalton’s new scale, at which temperature 
 mercury boils. This comes short of red 
 
EFFECTS OF HEAT. 
 
 heat, and is far below the highest attain¬ 
 able temperature. To supply this defi¬ 
 ciency, and to measure high temperatures, 
 various methods have been proposed. The 
 instruments thus applied to measure high 
 temperatures, are usually rvaxsxQdipyrometers. 
 That which has come into most genera! 
 use, was invented by the late Mr,, Wedge- 
 wood; but even on this instrument there 
 is still great room for improvement. 
 
 Wedgewood’s pyrometer consists of cy¬ 
 lindrical pieces of clay, composed in the 
 manner of earthen ware, and slightly 
 baked. When used, one of them is ex¬ 
 posed in a crucible to the heat proposed 
 to be measured, and after cooling, it is 
 found to be contracted in proportion to 
 the heat previously sustained; the quantity 
 of contraction being measured, indicates 
 ■ the temperature. 
 
 The utility of this instrument, it was 
 obvious, could be increased, by connecting 
 it with the mercurial thermometer, and-sby 
 ascertaining the proportional degrees of 
 
EFFECTS OF HEAT. 
 
 each. This was accordingly done by Mr. 
 Wedgewood. Its scale commences at red 
 heat,, fully visible in day-light. Its whdle 
 range is divided into 240 equal degrees, 
 each of which is calculated to be equal to 
 130° of Fahrenheit. The lowest, or 0, is 
 found about 1077° of Fahrenheit (suppos¬ 
 ing the . common scale continued above 
 boiling merctuy), and the highest 32277°. 
 
 In i^ig-. 4, is given a diagram, which 
 may .seiwe farther to illustrate the con¬ 
 nection between the, mercurial thermom¬ 
 eter, and that of Mr. Wedgewood. 
 
 The following table exhibits some of 
 the more remarkable temperatures in the 
 whole range of Reaumur, Fahrenheit, Cel¬ 
 sius, and Wedgewood’s thermometers. 
 
EFFECTS OF HEAT. 
 
 ,25 
 
 27. TABLE of ilie Degrees of different Ther¬ 
 mometers omitting Fractions, at ’which some 
 feniarkahh Chemical Phenomena occur. 
 
 REAU. 
 
 EAHR. 
 
 CENT. 
 
 
 54) 
 
 90 
 
 ■ 68 
 
 Greatest artificial cold ob¬ 
 served, produced by Mr. 
 Walker. 
 
 44 
 
 66 
 
 55 
 
 Nitric acid freezes, Fourcroy. 
 
 36 
 
 50 
 
 44 
 
 Cold observed at Hudson’s 
 Bay, M‘Nab. 
 
 36 
 
 46 
 
 43 
 
 Ether freezes. 
 
 ' 34 
 
 45 
 
 42 
 
 Ammonia exists in a liquid 
 
 
 39 
 
 39 
 
 Mercuiy freezes. 
 
 30 
 
 36 
 
 37 
 
 S ulphuric acid freezes, Thomson 
 
 28 
 
 31 
 
 35 
 
 Sulphurousacid liquid, Monge. 
 
 24 
 
 23 
 
 30 
 
 Cold observed at Glasgow on 
 the surface of snow, 1780. 
 
 23 
 
 22 
 
 30 
 
 Acetous acid freezes. 
 
 20 
 
 .14 
 
 25 
 
 Cold ob’seived at Glasgow, 
 1780. 
 
 19 
 
 11 
 
 24 
 
 Two parts of alcohol and one 
 
 18 
 
 10 
 
 23 
 
 Cold observed on the snow at 
 Kendal, 1791. 
 
 17 
 
 7‘ 
 
 14 
 
 Brandy freezes. 
 
 14 
 
 0 
 
 IS 
 
 Cold, produced by mixing 
 equal parts of snow and 
 muriate of soda. 
 
 7 
 
 16 
 
 9 
 
 Oil of turpentine freezes. 
 Margueron did not freeze 
 at—18 ilW//. 
 
 5 
 
 20 
 
 6 
 
 Strong wines freeze. 
 
 4 
 
 23 
 
 5 
 
 Fluoric acid freezes. Priestly. 
 Oil of bergamot and cin¬ 
 namon freezes, Marg. ■ 
 
 3 
 
 25 
 
 4 
 
 Human blood freezes. 
 
 2 
 
 28 
 
 2.5 
 
 Vinegar freezes’ 
 
 1 
 
 39 
 
 1.25 
 
 Milk freezes. 
 
 0 
 
 32 
 
 0. 
 
 Oxymuriatic acid melts, 77;om- 
 son. Water freezes. 
 
26 
 
 EFFECTS OF HEAT- 
 
 HEAtJ. 
 
 FAHK. 
 
 CENT. 
 
 
 2 
 
 36 
 
 2.5 
 
 Olive oil freezes. 
 
 3 
 
 39 
 
 4 
 
 Meat of hedgehogs and mar- 
 
 4 
 
 40 
 
 s 5 
 
 Oxyrauriatic acid boils, '1 'horn- 
 son, Equal parts of phos¬ 
 phorus and sulphur melt, 
 
 Pelktier. 
 
 5 
 
 43 
 
 6 
 
 Phosphorus bums slowly. 
 
 6 
 
 45 
 
 
 Sulphuric acid, Sp. gr. 1.78, 
 freezes, Keir. 
 
 10 
 
 55 to 66 
 
 12 
 
 Putrid fermentation, Jioarcroy. 
 
 12 
 
 59 
 
 15 
 
 Vinous fermentation begins, 
 Fourcroij, 
 
 14 
 
 64 
 
 17 
 
 Oil of anise freezes, 
 
 15 
 
 66 to 133 
 
 18 
 
 Animal putrefaction, 70 to 
 panary fermentation. 
 
 16 
 
 68 
 
 20 . 
 
 Camphor evaporates, Fourcroy 
 
 18 
 
 74 
 
 23 
 
 Butter melts. 
 
 19 
 
 75 
 
 24 
 
 Summer heat at Edinburgh. 
 
 20 
 
 77 
 
 25 
 
 Vinous fermentation rapid, 
 Fourcroy, Acetous ditto 
 begins. 
 
 21 
 
 80 
 
 26 
 
 Phosphorus burns in oxygen 
 gas. 104, Goettl'mg. 
 
 21 
 
 75 to 80 
 
 26 
 
 Summer heat in England, 
 
 21 
 
 80 
 
 26 
 
 Heat of the ocean under the 
 equator. 
 
 
 82 
 
 28 
 
 The adipocere of muscle melts. 
 
 23 
 
 88 
 
 31 
 
 Acetous fermentation ceases, 
 Fourcroy. Phosphorus is 
 ductile. 
 
 29 
 
 92 to 99 
 
 37 
 
 Heat of the human body. • 
 
 28 
 
 97 
 
 36 . 
 
 Axunge melts, Nicholson. 
 
 
 97 
 
 36 ' 
 
 Heat of a swarm of bees. 
 
 •29 
 
 98 
 
 36 
 
 Ether bods. 
 
 30 
 
 99 
 
 37 ■ 
 
 Phosphorus rsAs,-Pelletier. 
 
 31 
 
 100 to 103 
 
 39 
 
 Heat of domestic quadrupeds. 
 
 
 104 
 
 40 
 
 Resin of bile melts. 
 
 35 
 
 lOStolll 
 
 44 
 
 Heat of Birds. 
 
 33 
 
 107. 
 
 41 
 
 Feverish heat. 
 
 
 108 
 
 
 Hens hatch eggs. , 
 
 '^^34 
 
 109 
 
 42 
 
 Myrtle wax mdts, Cadet. 
 
 35 
 
 111 
 
 •44 • 
 
 Heat of the air near Senegal. 
 
EFFECTS OF HEAT. 
 
 27 
 
 • REA0. 
 
 EAHR. 
 
 CENT. 
 
 
 36 
 
 112 
 
 45 
 
 Spermaceti melts, Bostoci. 
 
 40 
 
 122 
 
 50 
 
 Phosphorus hums vividly, 
 Fourcroy. 148, Thomson. 
 
 42 
 
 127 
 
 53 
 
 Tallow melts, Nicholson. 
 
 44 
 
 130 
 
 54 
 
 Ammonia is separated from 
 
 48 
 
 140 
 
 60 
 
 Ammonia boils, Dalton. 
 
 49 
 
 ■ 142 
 
 « 61 
 
 Bees-wax melts, Irvine. 
 
 SO 
 
 145 
 
 63 
 
 Camphor sublimes, Venturi. 
 Ambergriomelts,ia(?rAn^e. 
 
 55 
 
 155 
 
 79 
 
 Bleached wax voe\ts,Nicholson. 
 
 59 
 
 165 
 
 74 
 
 Albumen coagulates. 156, 
 Black 
 
 Sulphur evaporates, Kirwan. 
 
 61 
 
 170 
 
 77 
 
 64 
 
 176 
 
 80 
 
 Alcohol boils. 174, Blach. 
 
 90 
 
 235 
 
 116 
 
 Adipocere of biliary calculi 
 
 melts, Fourcroy. 
 
 Water and volatile oils boil. 
 Bismuth 5 parts, tin 3, and 
 lead 2, melt. 
 
 80 
 
 212 
 
 100 
 
 83 
 
 219 
 
 104 
 
 Phosphorus begins to distil, 
 Pelletier. 
 
 88 
 
 230 
 
 110 
 
 Muriate of lime boils, Dalton. 
 
 89 
 
 234 
 
 111 
 
 Sulphur melts, Hojie. 212°, 
 Fourcray. 185°, Kirovan. 
 
 93 
 
 242 
 
 116 
 
 Nitrous acid boils. 
 
 96 
 
 248 
 
 120 
 
 Nitric acid boils. 
 
 103 
 
 264 
 
 130 
 
 Air breathed by the human 
 species, with tolerable ease, 
 Phil. Transac. osol. 65. 
 
 112 
 
 283 
 
 140 
 
 White oxide of arsenic su¬ 
 blimes. Alloy of equal parts 
 of tin and bismuth melts. 
 
 120 
 
 303 
 
 150 
 
 Sulphur burns slowly, and 
 camphor melts, Venturi. 
 
 134 
 
 334 
 
 168 
 
 Alloys, tii: 3 and lead 2, and 
 tin 2 and bismuth 1, melt. 
 
 182 
 
 442 
 
 227 
 
 Tin melts, Crichton. 413, Ir¬ 
 vine. 
 
 190 
 
 460 
 
 238 
 
 Tin 1, and lead 4, melt. 
 
 197 
 
 476 
 
 248 
 
 Bismuth melts. Irvine. 
 
 226 
 
 540 
 
 282 
 
 Arsenic sublimes. 
 
 232 
 
 554 
 
 290 
 
 Phosphorus boils, Pelletier. 
 
EFFECTS OF EEAT. 
 
EFFECTS OF HEAT, 
 
 11100 
 
 14.331 
 
 10177 
 
 12257 
 
 12777 
 
 13267 
 
 134.27 
 
 18627 
 
 20577 
 
 10320 
 
 11414 
 
 Working heat of 
 plate glass. 
 
 Flint glass furnace. 
 
 Cream coloured 
 ae.ware fired. 
 
 Welding heat of 
 
 Worcester china 
 vitrified. 
 
 Welding heat of 
 iron greatest. 
 
 Stone ware fired. 
 
 Chelsea china vitri¬ 
 fied. 
 
 Derby china. 
 
 Flint glass furnace 
 
 Bow china vitrified. 
 
 Equalpartsof chalk 
 and clay melt. 
 
 Plate glass furnace 
 strongest heat. 
 
 Smith’s forge. 
 
 Cobalt melts. Cast 
 iron melts. 
 
 Bristol china no 
 vitrification at 
 
 Nickel melts. Hes¬ 
 sian crucible melt¬ 
 ed. ' 
 
 Soft iron nails melt¬ 
 ed with the cru- 
 
 Iron melts. 
 
 Manganese melts. 
 Air furnace. 
 
 Platinum, tungsten, 
 molybdenum, ur- 
 
 nium, melt. 
 
 Greatest heat ob¬ 
 served. 
 
 Extremityofwedge- 
 wood’s scale. 
 
EFFECTS OF HEAT. 
 
 N. B. As many of these higher num¬ 
 bers were calculated from Wedgewood’s, 
 by the sliding rule, the two or three first 
 figures only can be depended upon as cor¬ 
 rect. They will be found, however, to be 
 sufficiently accurate for most purposes. 
 
 For more full information respecting 
 various constructions of tliermometers and 
 pyrometers, I beg leave to refer to Mr. 
 Murray’s System of Chemistry, vol. 1st. 
 I shall, however, when I come to speak of 
 Mr, Leslie’s experiments, give an account 
 of his diferential thermometer. 
 
EFFECTS OF HEAT. 
 
 31 
 
 SECTION n. 
 
 Of Expansion. 
 
 28. Expansion of bodies is an im¬ 
 portant effect of heat. Solids are least 
 expanded, liquids more, and elastic fluids 
 most of all. The law of expansion of all 
 permanently elastic fluids, has already 
 been noticed (Art. 23.), it remains now to 
 notice liquid and solid bodies. 
 
 29. Every body receiving heat, with a 
 few exceptions, when accurately measured, 
 is found to be enlarged, or expanded. 
 
 30. It may be proper to take notice of 
 some of the exceptions to this law,—^that 
 bodies are expanded by heat. The inost 
 general exception is, that increase of bulk 
 which takes place in several substances in 
 changing from the fluid to the solid state. 
 This is remarkably the case with water, the 
 expansion of which, in freezing, is capable 
 of overcoming a very great resistance, as 
 was proved by Mr. Boyle, by the Floren- 
 
EFFECTS OF HEAT. 
 
 tine academicians, and, more lately, by 
 Major Williams. In one of bis experi¬ 
 ments, by the expansive force of freezing, 
 
 an iron plug, weighing 21 lbs, was pro- 
 jected to a distance of 415 feet, with a 
 velocity of niore than 20 feet in a second*. 
 
 Hence the .bursting, during frost, of 
 pipes for conveying water, the raising of 
 pavement,^ the falling of parts of neglected 
 buildings, the splitting of trees, rocks, &c. 
 
 31. But a phenomenon still more sin¬ 
 gular is exhibited by water, it expands not 
 only in the instant in which it passes to 
 the solid state, but before it reaches its 
 freezing point. This singular phenom¬ 
 enon appears first to have been observed 
 by Dr. Croune, towards the close of the 
 17th century. It was afterwai'ds observed 
 by Mairan; but De Luc seems to have been 
 the first who attempted to investigate it 
 with precision. Dr. Hope has since made 
 experiments, from which he infers, that 
 water obtains its maximum density at 40°, 
 
 • Transactions of Royal Society of Edinburgh, vol. 3. p. 23. 
 
EFFECTS OF HEAT. 
 
 33 
 
 that is, 8° warmer than at the freezing 
 point, or 32°. Mr. Dalton has also inves¬ 
 tigated this subject, and from his experi¬ 
 ments infers, “ that the greatest density of 
 
 water, is at or near the 36 ° of the old scale, 
 and 37 ° or 38 ° of the new scale; and fur¬ 
 ther, tliat the expansion of thin glass is 
 nearly the saine as that of iron, whilst that 
 of stone ware is f, and brown earthen 
 ware I of the same 
 
 32. Permit me to direct the reader’s 
 attention to this very remarkable fact, that 
 . all bodies are condensed by cold without 
 limitation, water only excepted, whict we 
 have just seen is, at its greatest density, at 
 36° of Fahrenheit’s scale. This exception 
 to one of those general laws-of nature, is a 
 sti'iking proof of contrivance in the arrange¬ 
 ment of the universe. Were it otherwise, 
 all the fresh water within the polar circles 
 must inevitably have been frozen to a very 
 great depth in one winter, and a great 
 portion of what is now the most temper- 
 
 " Dalton’s Chemical Philosophy, p. 34. 
 
 E 
 
34 
 
 EFFECTS OF HEAT. 
 
 ate part of the globe, rendered a dreary- 
 waste. 
 
 To understand this, let us see -what 
 takes place in the freezing of a fresh water 
 lake. When the cold air comes in contact 
 with the particles at the surface, they are 
 cooled, and becoming heavier descend 
 until they are cooled down to the point 
 of greatest density. Were this 32° then 
 the whole water would continue this in- 
 •ternal motion until it arrived at the freez¬ 
 ing point, and being all equally cold, 
 would become all at once solid ice. 
 
 But the water is heaviest at 36°, of 
 course whenever, it is all cooled down to 
 that point, the internal motion ceases, and 
 the surface becomes gradually. colder un¬ 
 til it arrive at the freezing point, when a 
 thin body of ice forms a covering to the 
 water, and particularly when snow is 
 added, serves to protect it from the influ¬ 
 ence of the colder atmosphere., 
 
 For a fuller account of this instance of 
 
EFFECTS OF HEAT. 
 
 S5 
 
 the beautiful economy of nature as also 
 what relates to the influence of salt water 
 on the temperature of the globe, I may 
 refer the reader to Count Runiford’s 
 seventh Essay. 
 
 33. According to Smeaton, “ glass ex¬ 
 pands in length for 180° of temperature, 
 
 consequently it expands xio in bulk. But 
 water expands or rather more than 
 eighteen and one-half times as much j'.” 
 
 34. A knowledge of the comparative 
 expansions of solids, is of much import¬ 
 ance in the arts, and more particularly 
 in the construction of time-pieces, which 
 are much affected by the expansion of 
 metals. This has led to a number of 
 experiments on the subject; those of Mr. 
 Ellicot| appear to have been the first 
 which were made with any degree of ac- 
 cui'acy., He was followed in the same 
 inquiry by Smeaton ||, Roy and Trough- 
 . ton and also by M. Berthoud §. 
 
 • “ Nature is but a name for an effect, 
 
 “ U^hose cause is God.”—Ccu’/nr. 
 
 f.Dalton, page 31, 32. ^ Phil. Trans vol. 39. || Phil. Trans. 48. 
 
 § Essai sur Horlogerie, 2d edit. Paris, 17SS. 
 
36 EFFECTS OF HEAT. 
 
 Althougii we perceive sometliing like a 
 relation subsisting between the expansion 
 and fusibility of solids, those which are 
 most , fusible, as antimony, tin, lead, &c. 
 expanding most, yet it must be confessed, 
 that we know but very little with regard 
 to the connection which subsists between 
 the expansibility and other physical pro¬ 
 perties of solids. 
 
 No general law has hitherto been dis¬ 
 covered, respecting the ratio of expansion 
 of solid bodies; but for all practical pur¬ 
 poses, we may adopt the notion of the 
 equable expansion of solids. Glass, how¬ 
 ever, is an exception, for it has been found 
 to expand in a ratio which increases with 
 the temperature. 
 
 For measuring the longitudinal expan¬ 
 sion of solids, various instruments, or py¬ 
 rometers, have been invented, accounts of 
 which may be found in most books, on 
 natural philosophy. “ The longitudinal 
 expansion being found, that of the bulk 
 may be derived from it, and will be three 
 
EFFECTS OF HEAT. 37 
 
 times as much. Thus, if a bar of 1000 
 
 expand to 1001 by a certain temperature, 
 
 then a 1000 cubic inches of the same, will 
 become 1003 by the same temperature 
 
38 EFFECTS OF HEAT. 
 
 35 . TABLE of EXPANSIONS, for 180 ” of 
 
 Fahrenheit*. 
 
 Solids. 
 
 Earthen ware. 
 
 
 in Bulk. 
 
 Wedge wood says, 
 that earthen ware 
 made porous by 
 charcorJ, expanded 
 only one-third as 
 much as when 
 solid. 
 
 
 .000416 
 
 .0012 
 
 Dalton. 
 
 Stone ware. 
 
 Wood. . 
 
 .000208 
 
 .0012 
 
 Do. 
 
 Much less than glass. 
 Rittenhouse. 
 
 Glass rods and tubes. 
 
 .000208 
 
 .0025 
 
 Dalton. 
 
 -bulbs tbiu. 
 
 .001234 
 
 .0037 
 
 Do. 
 
 
 00077615 
 
 .002330 
 
 Roy.—Phil. Trails. 
 
 ■ 1785. He had be¬ 
 fore found a glass 
 tube expand four 
 
 
 50083333 
 
 .002502 
 
 Smeaton, Philosoph. 
 Transac. 1754. 
 
 Glass rod. 
 
 Deal. 
 
 00080787 
 
 .002426 
 
 Roy, the same glass 
 as the tube. 
 
 Roy, 1777, as glass. 
 
 Plarina. 
 
 .000856 
 
 .002570 
 
 Borda. 
 
 Platina and glass. 
 
 .0011 
 
 .0033 
 
 Berthoud. 
 
 Regulusof antimony.l 
 
 .001083 
 
 .003253 
 
 Smeaton. 
 
 Cast-iron prism. 
 
 .0011094 
 
 .003332 
 
 Roy. 
 
 Cast-iron. 
 
 .0011111 
 
 .003337 
 
 Lavoisier. 
 
 Steel rod. 
 
 .0011447 
 
 .003438 
 
 Roy. 
 
 Blistered Steel. 
 
 .001125 
 
 .003379 
 
 Phil. Trans. 1795, 
 428. 
 
 
 .001150 
 
 .003454 
 
 Smeaton. 
 
 Steel. 
 
 .0011574 
 
 .003476 
 
 Lavoisier. 
 
 Hard SteeL 
 
 .001225 
 
 -003679 
 
 Smeaton. 
 
 Annealed Steel. 
 
 .00122 
 
 .00367 
 
 Musschenbroefc. 
 
 Tempered Steel. 
 
 .00137 
 
 .00411 
 
 Musschenbroek., 
 
 • See Dalton’s Chem. PhiL p. 44. and 
 p. 390—3S1. 
 
 Young’s Nat. Phil. vol. 2. 
 
EFFECTS OF HEAT. 39 
 
 Solids. 
 
 in Length 
 
 in Bulk. 
 
 
 Trnn. 
 
 .001156 
 
 .003472 
 
 Borda. 
 
 
 .001258 
 
 .003779 
 
 
 Annealed Iron. 
 
 .00133 
 
 .00400 
 
 
 Hammered Iron. 
 
 .00139 
 
 .00417 
 
 
 Bismuth. 
 
 .001392 ■ 
 
 .004180 
 
 
 Annealed gold. 
 
 .00146 
 
 .004.38 
 
 
 Gold. 
 
 •0015 
 
 .0045 , 
 
 EUicot, by compari- 
 
 Gold wire. 
 
 .00167 
 
 .00502 
 
 Musschcnbroek. 
 
 Copper hammered. 
 
 .001700 
 
 .005109 
 
 Smeaton. 
 
 Copper. 
 
 .00191 
 
 .00573 
 
 Musschenbroek. 
 
 Brass. 
 
 .001783 
 
 ;005359 
 
 
 Brass scale, supposed 
 
 .0018554 
 
 .005576 
 
 Roy. 
 
 from Hamburgh. 
 
 
 
 Cast Brass. 
 
 .001875 
 
 .005635 
 
 Smeaton, 
 
 English plate brass 
 
 .0018928 
 
 ,005689 
 
 Roy. 
 
 
 
 
 English plate brass 
 
 .0018949 
 
 .005695 
 
 Roy. 
 
 
 
 
 
 .001933 
 
 .005811 
 
 Smeaton. 
 
 Brass. 
 
 .00216 
 
 .00648 
 
 Musschenbroek. 
 
 Copper 8 tin 1. 
 
 .001817 
 
 .005461 
 
 Smeaton. 
 
 Silver. 
 
 .00189 
 
 .005681 
 
 Herbert. 
 
 — 
 
 .0021 
 
 .0063 
 
 Ellicott, by com- 
 
 __ 
 
 .00212 
 
 .00636 
 
 Musschenbroek. 
 
 Brass 16 tin 1. 
 
 .001908 
 
 .005736 
 
 Smeaton. 
 
 Speculum metal. 
 
 .001933 
 
 .005811 
 
 Smeaton. 
 
 Spelter solder brass 
 
 .002058 
 
 .006187 
 
 Smeaton. 
 
 Fine pewter. 
 
 .002283 
 
 .006866 
 
 Smeaton. 
 
 Grain tin. 
 
 .002483 
 
 .007469 
 
 Smeaton. 
 
 Tin. 
 
 .00284 
 
 .00852 
 
 Musschenbroek. 
 
 Soft solder, lead 2 
 
 .002508 
 
 .007545 
 
 Smeaton. 
 
 Zinc 8 tin 1 a little 
 
 .002692 
 
 .008095 
 
 Smeaton. 
 
 hammered. 
 
 
 
 
 Lead. 
 
 .002867 
 
 .008625 
 
 Smeaton. 
 
 
 .00344 
 
 .01032 
 
 Musschenbroek. 
 
 Zinc. 
 
 .002942 
 
 .008850 
 
 Smeaton. 
 
 Zinc hammered out 
 
 .003011 
 
 .009061 
 
 Smeaton. 
 
 half aninchperfoot. 
 
 
 
 
40 
 
 EFFECTS OF HEAT. 
 
 laiquids. 
 
 Expansion in Bulks. 
 
 Mercury, ... - . . . . 
 
 Water, 
 
 Water saturated with salt, ... 
 Sulphuric acid, ....... 
 
 Muriatic acid, . . - - - - - 
 Oil of turpentine, ...... 
 
 Ether, . ........ 
 
 Fixed Oils, ........ 
 
 Alcohol, 
 
 Nutiic acid, .. 
 
 .0200 = -h 
 .0466 = -5rT.T 
 .0500 = ^ 
 
 .0600 =tIt 
 .0600 = ^ 
 •.0Y00=tV 
 
 .0700 = 
 .0800=t4-t 
 .0110 = ^ 
 .0110 = I 
 
EFFECTS OF HEAT. 
 
 41 
 
 SECTION III. 
 
 On the Speckle Heat of Bodies. 
 
 36. It was already observed, (Art. 3.) 
 that different bodies at the same tempera¬ 
 ture, and showing the same degree on the 
 thermometer, really contain different 
 quantities of heat. 
 
 This diversity of the quantity of heat 
 contained in different bodies, is called 
 specific heat] and, accordingly, tables of the 
 specific heat of bodies, showing their com¬ 
 parative attractions for heat, have been 
 formed in a similar manner with tables of 
 specific gravity, which show the compara¬ 
 tive weights of bodies of equal bulks. 
 
 Sometimes the specific heat of bodies is 
 deduced from equal weights^ and some¬ 
 times from equal hulis, but it seems to be 
 most correct to deduce them from equal 
 bulks 
 
 » See Dalton’s Chemical Philosophy, p. 2. 
 
 F 
 
42 
 
 EFFECTS OF HEAT. 
 
 Not being susceptible of measurement 
 by the thermometer, different modes have 
 been contiiyed for estimating it. 
 
 Lavoisier and Laplace used an ingenious 
 contrivance called a calomiter, for investi¬ 
 gating the specific heat of bodies. It was 
 calculated to , show the quantity of ice, 
 which any body heated to a given tem¬ 
 perature could melt; but, however ingen¬ 
 ious in its construction, this instrument 
 has not been found in practice to be . 
 sufficiently accurate. 
 
 Meyer attempted to find tlie specific 
 heats of dried woods, by observing the 
 times which equal volumes were in cool¬ 
 ing. These times^ he considered as pro¬ 
 portionate to the capacities, or specific 
 heats hulk for bulk., and when the thnes 
 
 were divideiLby the.specific gravities, the 
 quotients represented the capacities of 
 equal weights. This method was applied 
 by Mr. Leslie., to liquids, and has been 
 approved of, and followed by Mr. Dalton. 
 
EFFECTS_OF HEAT. 
 
 43 
 
 37. The important fact of the absorption 
 of heat, during the conversion of ice into 
 water, appears to have been first observed, 
 separately and unknown to each other, by 
 De Luc, Black, and Wilkie, about the year 
 1755. On this experiment. Dr. Black 
 principally founded his doctrine of latent, 
 heat, . Dr, Irvine and Dr. Crawford, ex¬ 
 plained the circumstances somewhat dif¬ 
 ferently, by the theory of a change of 
 capacity for heat. Dr. Black’s theory led 
 to very vague, indistinct, and inaccurate 
 notions on the subject; nor was the word 
 capacity well chosen. The term specific heat,, 
 is that which is more approved by later 
 writers, particularly Dalton and Leslie*. 
 
 38. By the method already mentioned, 
 (Art. 38.) making proper allowance for 
 'the containing glass vessels, Mr. Dalton 
 made his experiments on the specific heats 
 of various bodies^ the results of which 
 will be found in the following Table. It 
 will be sufficient to illucidate the use. of 
 
 » See Dalton’s Chem. Phil—-Leslie’s Inquiry, p. 529, also Mr. Til- 
 loch’s paper, Phil Mag. 1808, p. 70. 
 
44 
 
 EFFECTS OF HEAT. 
 
 the table, to give water and mercury as 
 examples. 
 
 “ If the whole quantity of heat in a 
 measure of water of a certain tempera¬ 
 ture be denoted by 1, that in the same 
 measure of mercury will be denoted by .5 
 nearly: hence the specific heats of water, 
 and mercury, of equal bulks^ may be sig¬ 
 nified by 1 and ,5 respectively. 
 
 “ If the specific heats, be taken from 
 equal weights of the two liquids; then they 
 will be denoted by 1 and .04 nearly, because 
 we have to divide .5 by 13.6,' die specific 
 gravity of mercury 
 
 ■ Mr. Dalton has discovered that water 
 increases in its capacity for heat with 
 the increase of temperature, and infers, 
 ■that as much heat is necessary to raise 
 water 5“ in the lower part of Fahrenheit’s 
 scale, as is required to raise it 7° in the 
 higher, and 6° in the middle. 
 
 ♦ Dalton, p. 
 
EFFECTS OF HEAT. 
 
 45 
 
 39. TABLE of Specific Heats. 
 
 Hydrogen - 
 
 Oxygen - - 
 
 Common air 
 Carbonic acid 
 
 Aqueous vapo 
 
 
 21.40* 
 
 4.75* 
 
 1.79* 
 
 1.05* 
 
 .79* 
 
 1.55* 
 
 .002 
 
 .006 
 
 .002 
 
 .002 
 
 .001 
 
 .001 
 
 LIQUIDS. 
 
 Water .. 
 
 Arterial blood.. 
 
 Milk (1.026). 
 
 Carbonat. of ammonia (1.035) . . . . 
 
 Carbonat. of pot-ash (1.30) - - - . - 
 
 Solut. of ammonia (.948) . . . . . 
 
 Common vinegar (1.02) 
 
 Venous blood .. 
 
 Solut. of common salt (1.197) - - - 
 
 Solut. of sugar (1.17) ....... 
 
 Nitric acid (1.20). 
 
 Nitric acid (1.30) .- 
 
 Nitric acid (1.36) - 
 
 Nitrate of lime (1.40) 
 
 Sulphuric acid and water, equal bulks - - 
 Muriatic acid (1.153) ....... 
 
 Acetic acid (1.056) 
 
 Sulphuric acid (1.844) - -. 
 
 Alcohol (.85). 
 
 Ditto (. 817). 
 
 Sulphur: ether (.76) 
 
 Spermaceti oil (.87) 
 
 Mercury ........... 
 
 1.00 
 
 1.03* 
 
 .95 
 
 .75 
 
 1.03 
 
 •78 
 
 .77 
 
 .76 
 
 .68 
 
 .35 
 
 .76 
 
 .70 
 
 .52 
 
 .04 
 
 1.00 
 
 1.00 
 
 .98 
 
 .70 
 
 •55 
 
46 
 
 EFFECTS OF HEAT. 
 
 Quicklime . .. 
 
 Pit^coal (1.27),. 
 
 Charcoal - 
 
 Chalk - -. 
 
 Hydrat. lime - 
 Flint glass (2.87) - 
 
 Muriate of soda ......... 
 
 Sulphur ........... 
 
 Nickel 
 
 Zinc. 
 
 Silver ............ 
 
 Tin ... -. 
 
 Antimony - 
 
 Gold. . ............ 
 
 Bismuth - - - 
 
 Oxides of the metals surpass the metals 
 themselves, according to Crawford. 
 
 .30 
 
 .28 
 
 .26* 
 
 .27 
 
 .25 
 
 .13 
 
 .11 
 
 .11 
 
 .10 
 
 .10 
 
 .08 
 
 .07 
 
 .06 
 
 .05 
 
 .04. 
 
 .04 
 
 .36 
 
 .67 
 
 1.00 
 
 ..97 
 
 .98 
 
 .78 
 
 .45 
 
 .40 
 
EFFECTS OF HEAT. 
 
 47 
 
 Bemarhs on the Table. 
 
 “ The articles marked * are from 
 Crawford. Notwithstanding the ingen¬ 
 uity and address'displayed in his experi¬ 
 ments on the capacities of the elastic 
 fluids, there is reason to believe his results 
 are not very near approximations to the 
 truth; we can never expect accmracy when 
 it depends upon the observation of 1 or 2 
 tenths of a degree of temperature after a 
 tedious and complicated process. Great 
 merit is undoubtedly due to him for the 
 attempt.—^The difference between arterial 
 and venous blood, on which he has 
 founded the beautiful system of animal 
 heat, is remarkable, and deserves further 
 inquiry!.” For some account of Dr. Craw¬ 
 ford’s theory here alluded to, see Thomson’s 
 Chemistry, vol. iv. p. 72,—also, Adam’s 
 Lect. on Nat. Phil. vol. 1. p. 396. But 
 those who wish fuller iirformation, I woirld 
 refer to Dr. Crawford’s valuable “ Ex¬ 
 periments and observations on Animal 
 Heat.” 
 
 f Dalton p. 6S'. 
 
48 EFFECTS OF HEAT. 
 
 40. “ Water appears to possess the 
 greatest capacity for heat of any pure 
 liquid yet known, whether it be compared 
 with equal bulks or weights; indeed it 
 may be doubted, whether any solid or 
 liquid whatever contains more heat than 
 an equal bulk of water of the same tem¬ 
 perature. The great capacity of water, 
 arises from the strong affinity which 
 both its elements, hydrogen, and oxigen, 
 have for heat. Hence it is that solutions 
 of salts in water, contain generally less 
 heat in a given volume than pure water: 
 for salts increase the volume of water as 
 well as the density, and having mostly a 
 small capacity for heat, they enlarge the 
 volume of the water more than proportional 
 to the heat they contribute 
 
 41. It is of importance to obtain the 
 exact specific heat of the elastic fluids, 
 because it has an intimate connection 
 with the phenomena of combustion, and 
 of heat in general. Of these, Mr. Dalton 
 has given a theory, upon the principles of 
 
 • Dalton, p. 64. 
 
EFFECTS OF HEAT. 
 
 49 
 
 which, he has calculated the following 
 table, respecting which he says, 
 
 We^shall have the specific heats, of the 
 several elastic fluids, as in the following 
 table. In order to compare them with 
 that of water, we shall further assume the 
 the specific heat of water, to that of steam, 
 as 6 to '7, or as 1 to 1.166.” 
 
 42. “ TABLE of the Specific Heats of Elastic 
 - • Fluids. 
 
 Hydrogen - 
 Azote •- - 
 
 Oxygen - - 
 
 Atmos, air - 
 Nitrous gas 
 Nitrous oxide 
 Carbonic acid 
 Ammon, gas 
 . Carb. hydrogen 
 
 “ Let US now see how far these results 
 will accord with experience. It is remark¬ 
 able, that the heat of common air comes 
 out nearly the same as Crawford found it 
 by experiment; also hydrogen excells all 
 the rest, as he determined, but oxygen is 
 much I''wer, and azote higher. The 
 G 
 
 - - 9.382 ,, Olefiant gas - . 1.5SS 
 
 - - 1.866 Nitric acid - . . .491 
 
 1.333 Carbonic oxide - - .'ITJ 
 
 - - 1.759 Sulph. hydrogen - .583 
 
 - - .777 I Muriatic acid . . .424 
 
 - - .549 I Aqueous vapour - 1.166 
 
 - - .491 I Etlier. vapour - . .848 
 - - 1.555 I Alcohol, vapour - - .586 
 
 - - 1333 Water .... I.OOO 
 
50 
 
 EFFECTS OF HEAT. 
 
 principles of Crawford’s doctrine of animal 
 teat, and combustion, however are not at 
 aU afected with the change 
 
 43. The phenomenon of animal heat 
 has from the earhest ages been the subject 
 of philosphical discussion, but its cause 
 seems not yet ascertained. Of this, there 
 are various degrees, some animals preserv¬ 
 ing a heat of 100° or more in all tempera¬ 
 tures of the atmosphere; others, particularly 
 the more imperfect, keep only a few degrees 
 warmer than the medium, with which they 
 are surrounded. That of the human body 
 is from 96° to 98°, and it is truely wonder¬ 
 ful that it shotdd remain nearly the same 
 in all climates. Men have lived in cold 
 greater than that at which mercury freezes, 
 (which is at 39° below zero,) and in an at¬ 
 mosphere above the heat of boiling water. 
 Mr. M‘Nab observed cold at Hudson^s Bay 
 50° below zero. While the human species 
 have, with impunity, breathed air 264° f, 
 none of the inferior animals, seem capable 
 
 * Dalton, page 75, 74 . 
 
 t See Phil. Tran. Votes. 
 
EFFECTS OF HEAT. 
 
 SI 
 
 of sustaining this change of temperature, 
 while to man has been given this wonder¬ 
 ful power of enduring all the variety of 
 climates, which his necessities, or desire 
 of knowledge, could lead him to visit, 
 (Art. 27.) 
 
 I hope the following quotations, relative 
 to the power of animals to sustain heat, 
 will be acceptable to the reader. 
 
 “ Air has often been breathed by the 
 human species, with impunity, at 264:°. 
 TUlet mentions its having been respired at 
 300; and Morantin, one instance, at 325°, 
 and that for die space of five minutes. 
 Sonnerat found fishes, existing in a hot 
 spring at the Manillas at 158° *: and M. 
 Humboldt and M. Bonpland, in travelling 
 through the province of Quito, in South 
 America, perceived other fishes thrown up 
 alive, and apparently in health, from the 
 bottom of a vulcano, in the course of its 
 explosions along with water, and heated 
 
 • He graduates by Reaumur’s thermometer, and calculates the heat 
 upon this at S9°. 
 
52 EFFECTS OF HEAT. 
 
 vapour that raised the thermometer to 210°, 
 being only two degrees short of the boiling 
 point*.” 
 
 “ There are indeed numerous facts, all 
 ■ of which tend to confirm the statement of 
 these intrepid travellers. Dogs have exist¬ 
 ed without apparent inconvenience, in a 
 temperature of 236°, measured by Fah¬ 
 renheit’s thermometer; a heat exceeding 
 that of boiling water, by 24°. A species of 
 toenia has been fotmd alive in a boiled carp; 
 the oven-giirls in some part of Germany, 
 have sustained a heat of 257° for a quarter 
 of an hour; one girl supported it ten 
 minutes, when augmented to 288° without 
 inconvenience, and another, breathed in 
 air, heated to 325° for five minutes f; the 
 incombustible man, described by Dr. Sem- 
 entini, of Naples, would receive boiling oil 
 into his mouth, and bathe his fingers in 
 fused lead without injmy J; and, to cpme 
 nearer home. Sir Joseph ^ Banks, bore a 
 
 • AaniTersary oration deEvered, March 8, 1808, before the Medical 
 Society of London, by John Mason Good, F. R. S. 
 
 I Hist. Acad. Scienc. 1764. ; Phil. Mag. vol. mdi. • 
 
EFFECTS OF HEAT. 53 
 
 heated room, at 211°, while Sir Charles 
 Blagden, has himself given an account * 
 of his sustaining the heat of 260° in the 
 surrounding facticious atmosphere f 
 
 44. Bodies by changing their state, also 
 change their specific heat. By a change of 
 stare in bodies, is meant their successive 
 ■passage from solidity to liquidity, and 
 from tills to elastic fluidity, and contrari¬ 
 wise. Thus water may be in the state of 
 ice, of liquid, and of vapour, or steam. 
 
 A solid body, as ice, on becoming liquid, 
 acquires a great specific heat, even though 
 its bulk be diminished; and a liquid, as 
 water, acquires a greater specific heat, on 
 being converted into an elastic fluid. 
 
 It was already mentioned, (Art. 89.) that 
 the absorption of heat, during the conver¬ 
 sion of ice into water, was observed by 
 philosophers, about the year 1755; and Dr. 
 Crawford has shown, that by the laws of 
 
 * Phil Trans, vols, Ixv. and laviii. f Eclectic Rev. March, 1809. 
 
54 
 
 EFFECTS OF HEAT. 
 
 absorption and extrication of heat, resulting 
 from the change of capacity, which takes 
 place in the solid and fluid states of water. 
 Divine Providence, has wisely guarded 
 againk various sudden vicissitudes of heat 
 and cold upon the surface of the earth. 
 A vast quantity of heat is extricated in 
 freezing of large masses, which renders the 
 process very slow, while the great absorp¬ 
 tion of heat from the atmosphere', in 
 thawing, occupies much time, and prevents 
 that terrible devastation, which otherwise 
 would take place from torrents produced 
 by the sudden dissolution of ice and 
 
 45. During the conversion of water into 
 steam, a great quantity of heat is absorbed; 
 in consequence of which, when steam is 
 again converted into water, much heat is 
 extricated. 
 
 Hence the water which results from 
 condensation, forms an accurate compara¬ 
 tive measure of the heat extricated from 
 steam of the same density, and, for this 
 
EFFECTS OF HEAT. 55 
 
 purpose, it was applied in experiments 
 made by Mr. Houldswortb*, in comparing 
 the effects of steam-tubes of tin-plate with 
 those of cast-iron. The subject of steam 
 will be farther considered, after treating 
 of Ebullition. 
 
 » See Part II. 
 
36 EFFECTS OF HE 4 T. 
 
 SECTION IV. 
 
 Of Combustion. 
 
 46. Modem cHemists consider the 
 sources of heat, which are under the 
 control of art to be the following;— 
 Solar rays, electricity and galvanism, 
 condensation, mechanical action between 
 solids, including friction and percussion, 
 and chemical action, to which head com¬ 
 bustion belongs * 
 
 Our concern at present is with com¬ 
 bustion, but before proceeding to that 
 subject, I shall very shortly notice some 
 of the other sources of heat. 
 
 47. It has been long known, that col- 
 otu'ed bodies when exposed to the light of 
 the Sun, have their temperature raised in 
 proportion to the darkness of their colour. 
 —^The simple experiment of touching a 
 white and a black stone exposed to the 
 
 • Murray’s Chemistry, vol. i. p. 450. 
 
EFFECTS OF HEAT, 51 
 
 rays of the sun, would be su^cient to 
 giye any one an idea of this truth. To 
 ascertain this point, experiments were made 
 by Dr. Hooke, by Dr, Franklin, and since, 
 with more precision, by Mr, Davy 
 
 48. The temperature produced by the 
 direct action of the rays of the sim, seldom 
 exceeds 120°, but when they are concen¬ 
 trated, -they are capable of producing a 
 temperature as great at least, as the most 
 intense and violent fires f. 
 
 49. Condensation of volume, it is 
 well known, produces heat. This fact was 
 long ago observed; in condensing air in the 
 air-gun, A curious i application of this 
 principle was, a few years ago, invented 
 in France, and is now coming into use in 
 this country. I allude to an instrument 
 for kindling fungus, used instead, of the 
 tinder-box. It is simply a condenser, 
 which, by compressing the air into a very 
 small space, by a single stroke of the piston, 
 sets fire to the fungus. 
 
 * Thomson’s Chemistry, vol. i. page 419. f P^ge 416. 
 
 H 
 
58 
 
 EFFECTS-OF HEAT. 
 
 Mr. Dalton accounts for; the decrease 
 of temperature of the atmosphere as we 
 ascend, by' supposing that the natural 
 . equilibrium of, heat is an equality lU quantity 
 raxhex than, temperature. Air increases in 
 its capacity for heat by rarefaction. The 
 temperature must, therefore, be regulated 
 by the density of each atom of air, in the 
 same perpendictilar column, being pos¬ 
 sessed of the same quantity of heat. Now, 
 it is well known, that the density of the 
 air becomes less as we ascend, and, of 
 course, the heat also decreases 
 
 50. Mr. Dalton is likewise < of opinion, 
 that the heat produced by friction and 
 PERCUSSION of solid bodies, results, in 
 both cases, from the same cause, viz. con¬ 
 densation of volume, in the same manner 
 as the condensation of air and other bodies 
 produces'heat f. (See Art. 49.) 
 
 51. It was the opinion of Crawford, 
 Lavoisier, and many other modem chemists, 
 
 3. t Dalton’s Chemistry, p.I23—I3S. 
 
effect's OF HEAT. 59 , 
 
 that oxygenous gas was the sole or prin- - 
 cipal source of the light and heat produced 
 by combustion. But Mr. Dalton has 
 proved, diat although-this may be,nearly, 
 the case with regard to charcoal and pit- 
 coal, that it is not true with regard to 
 other combustible bodies. He concludes, 
 
 “ that the heat, and probably the light 
 also, evolved by combustion, must be con¬ 
 ceived to be derived both from the oxygen' 
 and the combustible body, and that each 
 contributes, for ought we know to the 
 contrary, in proportion touts specific heat 
 before the combustion,” ^ .{Art. 43.), 
 
 Fitel 
 
 52. Dr. Black considers the fuels corh- 
 monly used, under five divisions:—“ The 
 first may comprehend the fluid inflam- 
 ablesj to the second we may refer peat or 
 turf; to the third, charcoal of wood; to 
 the fourth, pit-coal charred; and to the 
 fifth, wood or pit-coal in a crude state, and 
 capable of yielding a copious and bright 
 flame.— 
 
 » Dalton’s Chem. Phil. p. 81~82. 
 
EFFECT'S OF HEAT. 
 
 53. " 1st, The fiidd injlamables- are con¬ 
 sidered as distinct from the Solid, on this 
 accovmt, that they are capable of burning 
 upon a •wick, and become in this way the 
 most manageable sources of heat; though^ 
 on account of their price, they are never 
 employed for producing it in great quan¬ 
 tity, and are only used when a gentle 
 degree, or a small quantity of heat is suf¬ 
 ficient. The species which belong to this 
 class, are spirit of wine and different oilSi” 
 
 54. “ The second kind of fuel men¬ 
 tioned, peat, is so spongy, that compared 
 •with the more solid fuels, it is unfit to be 
 employed for producing very strong heats. 
 —It is too bulky for this.—e cannot put 
 into a furnace, at a time, a quantity that 
 corresponds with the quick consumption 
 that must necessarily go on when the heat 
 is violent. There is no doubt a great dif¬ 
 ference in this respect, among different 
 kinds of this fuel; but this is die general 
 character of it. However, when we desire 
 to produce and keep up, by means of 
 cheap fuel, an extremely nuld gentle heat, 
 
EFFECTS OF MEAt. 61 
 
 we can hardly use any thing better, than 
 peat. But it is best to have it previously 
 charred^ that isj scorched, of burned to 
 black coal. The advantages gained by 
 charring it, will be presently explained. 
 When prepared for use in that manner, it 
 is capable of being made to burn more 
 slowly and gently, or will bear, without 
 being extinguished altogether, a greater 
 diminution of the quantity of air with 
 which it is supplied, than any other of the 
 solid fuels. Dr. Boerhaave found it ex-, 
 tremely convenient and manageable'in his 
 FurUtis Studiosorumi - 
 
 55. “ The next fuel in order, is the 
 charcoal of wood. This is the chief fuel 
 Used by the cheffliks abroad, and has 
 many good properties. It kindles quickly, 
 emits few watery or other vapours while 
 burning, and when consmned, leaves few 
 ashes, and those very light. . They are, 
 therefore, easily blown away, so that the 
 fire continues open^ or pervious to the 
 current of air which must pass through 
 it to keep it burning. This sort of fuel 
 
EFFECTS OF HEAT. 
 
 -too, is capable of producing as intense a 
 heat as' can be obtained by any; but in 
 those violent heats it is quickly consumed, 
 and needs to be frequently supplied. 
 
 - 55. “ Fossil coals charred^ called cinders 
 or coaks^ have, in many respects, the same 
 properties as charcoal of vsrood; as kin¬ 
 dling more readily in fiirnaces, than when 
 they ai'e not charred, and not emitting 
 watery or other gross smoke while they 
 bum. This, sort of charcoal is even greatly 
 superior to the other in some properties. 
 It is a much stronger fuel, or contains the 
 inflamable matter iii greater quantity, or 
 in a more condensed state. It is, therefore, 
 consumed much more slowly on all occa¬ 
 sions, and particularly when employed for 
 producing intense melting heats. The 
 only inconveniences that attend it are, that 
 when it consmnes, it leaves much more 
 ashes than the other*, and these much' 
 
 • I do not know that this is tlie case with the finest pit-coal. I 
 have seen some of the fines^Newcastle coals which did not leave one 
 fiftieth part of their weight of ashes, and even these did not seem 
 entirely consumed. 
 
EFFECTS OF HEAT. 
 
 63 
 
 heavier too, which are, therefoi'e, liable to 
 collect in such quantity, as to obstruct the 
 free passage of air through the fire; and 
 farther, that when the heat is very intense, 
 these ashes are disposed to melt or vitrify 
 into a tenacious drossy substance, which 
 ciogs the grate, the sides of the furnace, 
 and the vessels. This last inconvenience 
 is only troublesome, however, when the 
 heat required is very intense. In ordinary 
 heats the ashes do not-melt, and though 
 they are more copious and heavy than 
 those of charcoal of wood, they seldom 
 choke up the fire considerably, unless the 
 bars of the grate be too close together. 
 
 “ This fuel, therefore, is preferable in 
 most cases, to the charcoal of wood, on 
 account of its burning much longer, or 
 giving much moi'e heat before it is con¬ 
 sumed. T^e heat produced by equal qtian ■ 
 titles^ by weight of pit-coal^ wood^ charcoal, 
 a7td wood itself are nearly in the proportion 
 of 5, 4, and 3. The reason why both these 
 kinds of charcoal are preferred, on most 
 occasions, in experimental chemistry, to 
 
tjie crude wgod arid fossil-coal, from which, 
 fhey are produced, is, that the crude fuels 
 are deprived, by charring, of a consider¬ 
 able quantity of water, and some other 
 volatile principles, which are evaporated 
 during the process of charring, in the 
 form of sooty smoke or flame. These 
 volatile parts, while they remain in the 
 fuel, make it unfit (or less fit) for many 
 purposes in chemistry. For, besides ob¬ 
 structing the vents with sooty matter, 
 they require much heat to evaporate them, 
 and, therefore, the heat of the furnace in 
 which they are burned is much dimin¬ 
 ished, and wasted by every addition of 
 fresh fuel, until the fresh fuel is com¬ 
 pletely inflamed, and restores the heat to 
 its former strength. But these great and 
 sudden variations of the heat of a furnace, 
 are quite inconvenient in-most chemical 
 processes. In the greater number of chem¬ 
 ical operations, therefore, it is much more 
 convenient to use chaiTed fuel, than the 
 same fuel in its natural state. 
 
EFFECTS OF HEAT; 
 
 65 
 
 57. “ The last kind of fuel is wood, or 
 fossil coal in their crude state, which it is 
 proper to distinguish from the charcoals 
 of the same substances. The difference 
 consists in their giving a copious ■ and 
 bright flame, when plenty of air is admit¬ 
 ted to them, in consequence of which they 
 must be considered as fuels, very different 
 from charcoal, and adapted to different 
 purposes. 
 
 “ I had occasion formerly to remark, 
 when treating of inflamation, that flame is 
 produced from those substances only, 
 which are either totally volatile vsfhen heat 
 is applied to them, or which contain a 
 quantity of combustible taatter that is 
 volatile, or easily convertible into vapour 
 by heat; and that flame is nothing else 
 but this vapour set on fire, or which 
 becomes inflamed as fast as it arises from 
 the body which affords it. 
 
 : “ Of this nature, therefore, is the flame 
 of wood and fossiLcoal, when they are 
 -burned in their crude state. These fuels 
 I 
 
EFFECTS OF HEAT. 
 
 coatam a quantity of, inflamable matter, 
 that is volatile, and which, when a 
 ■moderate and stifled heat is applied to 
 them, evaporates in the form of oily and 
 sooty vapours and smoke, and diminishes 
 the heat instead of increasing it. But if 
 they are exposed to a stronger heat, and 
 air is freely admitted, the sooty vapours 
 are suddenly set on fire, or become flame, 
 and continue afterwards to burn as fast as 
 they arise from the wood or coal, in con¬ 
 sequence of which they produce a great 
 heat. 
 
 “ These flaming fuels, however, have 
 their particular uses, for which the others 
 are far less proper; for it is a fact, that 
 flame, when produced in great quantity, 
 and made to burn violently, by mixing it 
 with a proper quantity of fresh air, by 
 driving it on the subject, and throwing it 
 into whirls and eddies, which mix the air 
 
 with every part of the hot vapour, gives a 
 most intense heat. This proceeds from 
 the vaporous nature of flame, and the 
 perfect miscibihty of it with the air. As 
 
PFFECTS OF SEAT. 6f 
 
 the immediate contact and action, of air is 
 necessary to the burning of every corh- 
 bustible body, so the air, when properly 
 applied^ acts with far greater advantage on 
 flame, than on the solid aiid fixed inflam- 
 able bodies, for when air is applied to 
 , these last, it can only act on. their surface 
 or. the particles of them that are outermost; 
 whereas flame being a vapour or elastic 
 fluid, the air by proper contrivances can 
 be intimately mixed with it, and made to 
 act on every part of if, external and inter¬ 
 nal at the same time.—^The great power 
 of flame, which is the consequence of this, 
 does not appear when we try small quan¬ 
 tities of it, and allow it to burn quietly, 
 because the air is not intimately mixed 
 with it, but acts only on the outside, and 
 the quantity of burning matter in the 
 , surface of a small flame, is too small to 
 produce much efiect. But when fiarne 
 is produced in large quantity, and is pro¬ 
 perly mixed and agitated with air, its 
 power to heat bodies is immensely in¬ 
 creased; it is, therefore, peculiarly proper 
 ' for heating large quantities of matter to a 
 
68 
 
 EFFECTS OF HEAT. 
 
 violent degree, especially if the contact of 
 solid fuel with such matter is incon¬ 
 venient. Flaming fuel is used for this 
 reason, in many operations performed on 
 large quantities of metal or metallic min¬ 
 erals, in the m^hiug of glass, and in the 
 baking or burning of all kinds of earthen 
 ware. The potters kiln is a cylindrical 
 cavity, filled from, the bottom to the top 
 ■with columns of ware. The only inter¬ 
 stices are those that are left between the 
 columns; and the flame, when produced 
 in sufficient quantity, proves a torrent of 
 liquid fire, constantly flowing up through 
 the whole of those interstices, and heats 
 the whole pile in an equal manner. 
 
 Flaming fliel is also proper in many 
 works or manufactories, in which much 
 fuel is consumed, as in breweries, distil¬ 
 leries, and the Uke. In such works it is 
 evidently worth while to contrive the 
 furnaces, so that heat may be obtained 
 from the volatile parts of the fuel, as well 
 as from the fixed; for when this is done, 
 less fuel serves the purpose than would 
 
EFFECTS OF HEAT. 
 
 Otherwise be necessary. But this is little 
 attended to, or ill understood, in many of 
 those manufactories. It is not uncom¬ 
 mon to see vast clouds of black smoke 
 and vapour coming out of their vents. 
 
 “ This happens in consequence of their 
 throwing too large a quantity of crude 
 fuel into the furnace at once. The heat 
 is not sufficient to inflame it quickly, and 
 the consequence is, a great loss of heat*.” 
 
 58. I hope it will not be considered an 
 improper digression, to mention a subject 
 which has lately excited a good deal of the 
 public attention; I allude to the light pro¬ 
 duced from the gas proceeding from the 
 distillation of pit-coal. From the Philo¬ 
 sophical Transactions, it appears that, as 
 far back as the year 1735, it was known 
 as a fact, that coal yields an inflamable 
 gas, but its beneficial application seems to 
 have been reserved for Mr. Murdoch, in 
 the year 1792. The most extensive cot- 
 
 * Black’s I.e 
 
 s, vol. i. pages 312—Sl(^ 
 
70 
 
 EFFECTS OF HEAT. 
 
 ton-mill in the kingdom, has been, for 
 several years, lighted np with the gas from 
 coal. The following extract from a peri¬ 
 odical work of extensive circulation % as 
 giving a summary view of this subject, 
 and as containing soine valuable facts 
 respecrii^ fuel, I trust will be acceptable 
 to the reader. But those who wish to 
 pursue tie subject, I would refer to the 
 work alluded to, as well as to Mr. Mur¬ 
 doch’s “ Account of the Application of 
 Gas from Coal to Economical Purposes,” 
 published in the PhUosophicai Transac¬ 
 tions for 1808, and reprinted in Nichol¬ 
 son’s Philosophical Journal, the Philosophi¬ 
 cal Magazine, and the Monthly Magazine 
 for the same year. 
 
 “ Pit-coal exists in this island in strata, 
 which, as far as concerns the hundredth 
 generation after us, may be pronounced 
 inexhaustible; and is so admirably adapted, 
 both for domestic purposes and the uses 
 of the arts, that it is justly regarded as a 
 
 »Edinbmgh Review, vol. liii. page 478. 
 
EFFECTS OF HEAT. 
 
 71 
 
 most essential constituent of our national 
 wealth. When exposed to heat, as we see 
 it every day in our grates, it is manifestly 
 composed of a fixed base of carbonaceous 
 matter,; and a variety of evaporable sub¬ 
 stances, which are driven ofFin the form of 
 smoke and flame. But, instead of being con¬ 
 sumed in this open way, the coal may be dis¬ 
 tilled, and these evaporable matters collected 
 in proper vessels, and examined. They are 
 then found to contain, besides a consider¬ 
 able quantity of matter, which is condensed 
 by cold into tar and alkaline liquor, an 
 invisible elastic fluid, or gas, which no 
 cold nor affusion of water can condense or 
 absorb. It is a compound of two highly 
 inflamable gases, which chemists call the 
 light hydrocarbonate, and the heavy hy¬ 
 drocarbonate, or olefiant gas; and this 
 mixture burns with a very brilliant and 
 beautiful light. It is this gas which fur¬ 
 nishes the flame in our conimon. fires 
 
 “ • There are, in fact, according to Mr. Davy, three inflamable 
 gases g^ven out in our fires;—the' two we have mentioned, and the 
 gaseous oxide of carbon, which is known by its blue flame. They are 
 all distinctly perceptible; the light hydrocarbonate forms the main body 
 «f the flame; the olefiant appears in brilliant jets; and the gaseous 
 
effects of heat. 
 
 but its beauty is there impaired by the 
 unavoidable alloy of smoky vapour. A 
 separation, however, may be effected by 
 the distilling process, which , leaves the 
 pure aerial fluid such as we have described. 
 All the new plans for lighting vtith coal- 
 gas, proceed upon the principle of purify¬ 
 ing this fluid, collecting it in reservoirs, 
 and distributing it in tubes. From the 
 furnace where the coal is distilled, a main 
 pipe may convey all the evaporable matter 
 into a large reservoir or gasometer, where, 
 by various means—chiefly, we believe, by 
 washing with water, it may be freed from 
 impurities, and propagated through the 
 tubes in every direction by its own elas¬ 
 ticity. If nothing confine it, it will issue 
 from the extremities in an equable flow, 
 but still invisible, till a hghted taper be 
 applied, when it bursts into flame, and 
 continues to bum as long as the gas is 
 supplied. Mr. Accxun found, by a com¬ 
 parison of shadows, in the manner sug- 
 
 oiide is occasionally seen near the root of the flame, or in conuct with, 
 the coaL It is possbie that a small portion of this oxide may mix with 
 prepared gas. 
 
EFFECTS OF HEAT. 73 
 
 gested, by Count Rumford, that the light 
 of a. gas flame is to that of an equal-sized 
 flame of a candle or lamp, as 3 to 1 or, 
 in other tvords, that to light up a certain 
 space, one gas flame will give as much 
 light as three candles burning with a flame 
 of equal size. The products of the com¬ 
 bustion are, in both cases, the same,-*^ 
 water and carbonic acid gas; but with this 
 material difference, that candles frequently, 
 and lamps always, give out a quantity of 
 smoke and soot; whereas the combustion 
 of the gas is perfect, and leaves no sensible 
 residuum,-—notliing that can soil the most 
 delicate white. Its effects pn the air of a 
 room are,, therefore, less insalubrious than 
 those of a candle, since the only noxious 
 substance it yields is carbonic acid gas; 
 and this it produces in smaller quantity 
 thaa our common iighjts;. From the in- 
 
 • TVe sliauld have suspected the proportion Ovet-fated, fiad 
 liot the same accurate experimenters assured us, * that 500 cubic inches 
 of gas,, burnt from the orifice of a jet, so as to produce a ilame equal 
 in size to that of an ordinary candle, consumed 1075 cubicinches of 
 oxygen gas in the same time that a candle, kept burning in the best 
 possible manner^ consumed only 279; and we know, that the. intensity 
 of any artificial light depends on the rapidity with which oxygen 
 absorbad.’-^ee Appendix to Report of the Committee, &c. 
 
 K 
 
•74 
 
 EFFECTS OF HEAT. 
 
 flamable properties of the gas, explosions, 
 bursting of tubes, and other dangers might 
 be apprehended. But there is no ground 
 for such fears. On the contrary, nothing 
 can be more simple or easy in the man¬ 
 agement. The gas may be confined by a 
 stop-cock with perfect safety, and issued 
 as occasion requires. When it is exhausted, 
 the flame goes out as quietly as the flame 
 of a candle does, when the tallow is spent. 
 
 “ Such are the nature and properties of 
 this curious and beautiful substance, when 
 examined in a small way in the laboratory 
 of the chemist. But it frequently happens, 
 that theories perfectly just and elegant iii 
 themselves, and confirmed by experiments 
 on a small scale, with a nice apparatus and 
 skilful management, are yet, when at¬ 
 tempted in the large and wholesale way, 
 utterly incapable of being reduced to prac¬ 
 tice; and thus, many a promising plan has 
 ended with performing nothing. But, in 
 the case before us, there are facts, of the 
 description we want to be collected from 
 different quarters, and furnished by indi- 
 
EFFECTS OF HEAT. 
 
 75 
 
 viduals unconnected with each other, which 
 fully verify the anticipations of theory, arid 
 the conclusions of moi'e limited experi¬ 
 ment. 
 
 This substance (coke) is the residuum 
 that is found after all the evaporable mat¬ 
 ter has been expelled from the coal by 
 heat. It comes out from the distilling 
 process in large spungy masses, greatly 
 diminished in weight, but increased in 
 bulk nearly one-third. Though somewhat 
 more difficult of ignition than coal, it 
 burns longer, and gives out a steadier and 
 more intense heat. That it should do so, 
 will not appear strange , to . our chemixal 
 readers, (and who is there now, that does 
 not know something of chemistry?) when 
 it is considered that the quantity of mat¬ 
 ter, which, in the combustion of coal, is 
 changed from a solid to a state of elastic 
 fluidity, must necessarily carry off much 
 caloric in a latent state; while the glow 
 of the coke radiates with an intensity un¬ 
 impaired by any demand of this kind. 
 The same respectable chemist we formerly 
 
EFFECTS OF HEAT. 
 
 76 
 
 mentioned, bears testimony to the supe¬ 
 riority of coke, ‘ I have learned,’ says 
 Mr. Accum*, ‘ thai the heat produced by coke^ 
 njohen compared 'with that which can be obtained 
 from coal, is at least as 3 to 2.’ Thus he 
 found, that it required three bushels of coal 
 ro distil a given quantity of -water, and 
 only two of coke. He tried the two sub¬ 
 stances also by combustion, with a certain 
 measure of oxygen gas, by the fusion anti 
 the reduction of metals, &c.; and the same 
 result was obtained,—a result certainly not 
 unimportant, since it proves that, by being 
 forced to yield the material of a beautiful 
 light, coal is actually improved very con¬ 
 siderably in its power of giving heat, 
 
 “ Before taking leave of Mr. Winsor, we 
 shall present the reader with the results of 
 his analysis of coal, which, we should have 
 been cautious of admitting among authentic 
 facts, had not the Committee declared, that 
 the experiments were repeated in their pre¬ 
 sence, and that they corroborated Winsor’s 
 
 ' Appendix to Report of the Committee, &c. 
 
EFFECTS OF HEAT. 
 
 77 
 
 printed statement in the most satisfactory- 
 manner. Two pecks of Newcastle cbal^weigking 
 S6 lb., produced three pecks of coke, weighing 24 
 lb. 2 0 %., about 34 lb. of oily tar, and about 41 of 
 alkaline liquor) and, as the only other product 
 was gas, it is concluded that gas constituted the, 
 remainder of the weight, amounting nearly to 
 four poustdsT 
 
 59, ' I shall collect here the effect of 
 se-veral hinds of fuel in producing heat, as 
 given by authorities which have come un¬ 
 der my observation, and afterwards make 
 a comparative abstract of the result. The 
 distillation of water is a simple and satis¬ 
 factory mode of comparing the effects of 
 fuel. 
 
 60. Mr. Dalton says, for the sake of 
 those who are more immediately interested 
 in the economy of fuel, that the heat given 
 out by the combustion of 1 lb. of charcoal, 
 and, perhaps, also of pit-coal, is sufficient 
 (if there were no loss) to raise 45 or 50 lbs. 
 of water from the freezing to the boiling 
 temperature} or it is sufficient to convert 
 
*78 
 
 EFFECTS OF HEAT. 
 
 7 or 8 Ihs. of water into steam. If more 
 thaii this weight of coal be used, there is 
 a proportionate quantity of heat lost, which 
 ought, if possible, to be avoided 
 
 61. In Dr. Black’s Lectures, vol. i. page 
 184, we have the following note: “100 
 pounds weight of the best Newcastle coal, when 
 applied by the most judiciously constructed fur¬ 
 nace, will convert about D wine hogshead f of 
 water into steam that supports the pressure of 
 the atmosphere. 
 
 62. By this account, observes Count 
 Rumford, which he (Mr. Kirwan) tells me 
 is founded on experiments made by Mr. 
 Lavoisier, it appears, that equal quantities 
 of water under equal smfaces, may be 
 evaporated, and consequently equal heats 
 produced- 
 
 By 403 lbs. of coaks, 
 600 — of pit.coal, 
 600 — of charcoal, 
 
 10S9 — of oak, 
 
 By 17 of coaks, 
 
 10 of pit.coal, 
 40 of charcoal, 
 33 of oak 
 
 • Dalton’s Chemical Philosophy, page 82. 
 t Equal to 12.63 cnhic feet. 
 
 1 Rmnford’s Essays, vol. ii. page 134. 
 
EFFECTS OF HEAT. 
 
 79 
 
 “ From tne result of my 20tli experiment, 
 it appeared that 20-iV lbs. of ice-cold water 
 might be heated 180 degrees., or made to boil 
 under the mean pressure of the atmosphere, at 
 the level of the surface of the ocean, with the 
 heat generated in the combustion of \ lb. of 
 pine-wood. Computing from the result of 
 this experiment, and from the relative quan¬ 
 tities of heat producible from pine-wood’ 
 and from pit-coal, it appears that the heat 
 generated in the couibustion of \ lb. of pit-coal, 
 would make 36^ lbs. of ice-cold water boil .— 
 Hence it appears, that pit-coal should heat 
 36 times its weight of water, from the 
 freezing point to that of boiling; and as it 
 has been found by experiments, made with 
 great care by Mr. Watt, that nearly 5i times 
 as much heat as is sufficient to heat any 
 given quantity of ice-cold water to the 
 boiling point, is required to reduce that 
 same quantity of water, already boiling hot, 
 to steam; according to this estimation, the 
 heat generated in the combustion of \ lb. of coal, 
 shotdd be sufficient to reduce very nearly 7 lbs. 
 of boiling hot water to steam 
 
 • Count Rumford’s Essays, vol. ii. page 136,137. ^ 
 
80 EFFECTS OF HEAT, 
 
 Dn Crawford found, by an experiment 
 epnttived with much ingenuity, and whicli 
 appears to have been executed with the 
 utmost care, that the heat generated in the 
 combustion of 30 grains of charcoal raised 
 the temperature of 31 lbs. 7 oz. Troy=f 
 181.920 grains of water degrees of 
 Fahrenheit’s thermometer, •when none of the 
 heat generated was suffered to escape,. Con¬ 
 sequently, the heat generated in the combus¬ 
 tion of 1 lb, of charcoal, •would be sufficient to 
 heat 57.608 lbs, of ice-cold •water 180 degrees, 
 or to make it both, for 3157.9 grains of char¬ 
 coal are to 181.920 grains of water, as 1 
 of charcoal to 57.608 lbs. of water, 
 
 From the result of Mr. Lavoisier’s ex¬ 
 periments, it appeared tKat the quantities 
 of heat generated in the combustion of 
 equal weights of charcoal and dry oak, 
 are as 1089 to 600. Hence we may con¬ 
 clude, that equal quantities of heat are gen¬ 
 erated by 1 lb. of charcoal and 1.815 lbs, 
 of oak; consequently, that the heat gen¬ 
 erated in the combustion of 1.815 lbs. of 
 oak, would heat 57.608 lbs. of ice-cold 
 
EFFECTS OF HEAT. 
 
 81 
 
 water,—or 1 lb. of oak, 31.74 lbs. of ice- 
 
 cold water 180 degrees, or cause it to boil; 
 were no part of the heat generated in the com- 
 hustion of fuel lost ' 
 
 63. “ The comparative examination of 
 the intensity of the heat produced by bursting 
 charcoal and charred turf proves that the heat 
 of the latter is (to that of the former) nearly 
 in the proportion of three to one f. 
 
 '64. “ Mr. Watt finds, that it requires 
 eight feet surface of boiler to be exposed 
 to fire, to boil oflF one cubic foot of water 
 per hour, and that a bushel or 84 lbs. New¬ 
 castle coal, so applied, will boil off from eight 
 to twelve cubic feet 
 
 65. “ The heat expended in boiling olF 
 a cubic foot of water, is about six times as 
 much as would bring it to a boiling heat 
 
 * Count Rumford’s Essay, vol, li. page 139, 140. 
 f “ Inquiry into the comparative intensity of heat produced by the 
 combustion of charcoal and charred turf,” in the Memoirs of the Acad- 
 <miy of Sciences of Paris. Repertory of Arts, voL v. p. 419, 
 
 \ En. Brit. Supplement. 
 
 L 
 
82 
 
 EFFECTS OF HEAT. 
 
 from the medium temperature, (55°) in 
 
 this climate*.” 
 
 66. Mr. Watt, I believe, for his steam- 
 engines, in situations where wood is the 
 fuel employed, allows three times the weight 
 of wood, tliat he does of Newcastle coal. 
 
 67. Newcastle coal produces much more 
 heat than the generality of Scotch coal. A 
 bushel of Newcastle coal, which weighs \of a 
 cwt. is reckoned to produce as much heat as a 
 cwt. of Glasgow coal. 
 
 68. Small coal or culm, is much used 
 for steam-engines. From repeated trials, 
 made in the neighbourhood of Glasgow, 
 it requires just double the weight of culm that 
 it does of coal to produce the same heat. At 
 the prices in 1808, the cost of culm was 
 to that of coal, supplying the same work 
 as 12 is to 14, thus producing a saving of 
 4 by the use of culm. 
 
 »En. Brit. Supplement. 
 
EFFECTS OF HEAT, 
 
 83 
 
 69. “ A wax candle | of an inch ifi 
 diameter, loses a grain of its weight in 37 
 seconds, and consumes about three grains, 
 or 9 cubic inches of oxygen gas, produc¬ 
 ing heat enough to raise the temperature 
 of about 15000 grains of water a single 
 degree. According to the experiments of 
 Mr. Lavoisier and Mr. Laplace, the com¬ 
 bustion of 10 grains of phosphorus, 
 requires the consumption of 15 grains of 
 oxygen; the combustion of 10 grains of 
 charcoal 26, and of hydrogen gas 56; and, 
 bythe heat produced during the combustion 
 of a pound of phosphorus, 100 poxmds of 
 ice may be melted; during that of a pound 
 of charcoal, 96l; of hydrogen gas, 2951; of 
 wax, 133; and of olive oil, 149; and during 
 the deflagration of a pound of nitre, with 
 about one-sixth part of its weight of char¬ 
 coal, 12 pounds of ice may be melted*.” 
 
 70. The following table contains a 
 comparative abstract of the eflhct of sev¬ 
 eral kinds of fuel in producing heat. 
 
84: 
 
 EFFECTS OF HEAT. 
 
 The numbers in the fourth column, point 
 out the Articles in this Essay -which con¬ 
 tain the authority upon which the abstract 
 is made, or on -which the proportions are 
 calculated. 
 
 1- 2. 3. 4. 
 
 
 Suflicient -to raise from the 
 freezing to the boiling 
 point, Ilia, of water. 
 
 s-s 
 
 ji 
 
 g 
 
 w 
 
 1 _ 
 
 •5 
 
 
 1 lb. charcoal or pit-) 
 coal at a maximum, J 
 
 54 to SO 
 
 7or6 
 
 60 
 
 Dalton. 
 
 1 lb. of pit-coal. 
 
 
 7. 
 
 62 
 
 Count Rumford. 
 
 1 lb. charcoal. 
 
 57.608 
 
 10.9 
 
 62 
 
 Crawford. 
 
 1 lb. dry oak. 
 
 31.7 
 
 
 62 
 
 Lavoisier. 
 
 1 lb. of pine-wood. 
 
 20.1 
 
 
 62 
 
 Count Rumford. 
 
 1 lb. of Newcastle coal. 
 
 
 6. 
 
 64 
 
 Watt. 
 
 1 lb. da. do. 
 
 
 7.89 
 
 61 
 
 Black. 
 
 1 lb. do. do. 
 
 
 6.25 
 
 63 
 
 Watt. 
 
EFFECTS OF HEAT. 
 
 85 
 
 SECTION V. 
 
 Of the Motion of Heat 
 
 71. The temperature of bodies being 
 liable to perpetual fluctuation, to deter- 
 rnine the nature of the motion of heat in 
 the same body, and in its passage from 
 one body to another, arising from its 
 incessant tendency to an equilibrium, 
 becomes of much practical importance. 
 Dr. Ingenhouse to show the relative con¬ 
 ducting power of the different metals, 
 made this simple experiment;—he took 
 equal straight pieces of stout wire of the 
 different metals, drawn through the same 
 hole and of the same lengths, and dipping 
 them into melted wax. He then held 
 one end of each of these wires in boiling- 
 water, and observed how far the coating 
 of wax was melted by the heat commun¬ 
 icated through the metal, and with what 
 celerity the heat passed. 
 
 72. The property by which bodies 
 receive, and part v/ith heat v.'hen in com- 
 
86 
 
 EFFECTS OF HEAT. 
 
 mimication with others of a different tem¬ 
 perature, is termed their conducting power. 
 Those which have their ' temperature 
 quickly altered, hj communication with 
 other bodies, are said to be better con¬ 
 ductors of heat, than those which receive 
 and part with it more slowly. 
 
 13. The power of -conducting heat, 
 varies greatly according to the nature of 
 the subject. In general, it may be re¬ 
 marked that dense bodies are the best 
 conductors of heat, and that those which 
 are more rare conduct it very imperfectly. 
 The metals, for instance, are good conduc¬ 
 tors. Earthy substances conduct more 
 slowly. Wood is a very imperfect conduc¬ 
 tor. Hair, fur, feathers, &c. which form 
 the covering of animals, are still inferior 
 in their conducting power. The same 
 matter in its different states of aggregation, 
 differs in this property. Thus an iron bar 
 or an iron plate is a much better conduc¬ 
 tor than iron filings, and wood than saw¬ 
 dust. 
 
EFFECTS OF HEAT. 
 
 8*7 
 
 74. But though these experiments were 
 very ingenious and simple, and, perhaps, 
 sufficiently accurate for a great variety of 
 practical purposes, yet philosophers, when 
 the tnith can be more nearly ascertained, 
 are not satisfied with these approximations. 
 Professor Leslie described to me. an appar¬ 
 atus, which seems well calculated for this 
 purpose, but which he had not then ap¬ 
 plied. . I hope, however, he will soon 
 favour the public with the result of his 
 inq.uiries on this subject. 
 
 Dr. Ingenhouse, from his experiments, 
 concluded, “ that the conducting powers 
 of the metals which he examined, were in 
 the following order *. 
 
 Silver, 
 
 Gold, 
 
 Copper, I equal. 
 
 Platinum, "1 
 
 Steel f* inferior to the others. 
 Lead, J 
 
 •Jgur. de Phys, 1789, p. 68, 
 
EFFECTS OF HEAT. 
 
 “ Next to metals, stones seem to be the 
 best conductors; but this property varies 
 considerably in different stones. Bricks 
 are much worse conductors than most 
 tones. 
 
 “ Glass seems not to differ much froni 
 stones in its conducting power. Like 
 them, it is a bad conductor. This is the 
 reason that it is so apt to crack on being 
 suddenly heated or cooled. One part of 
 it, receiving or parting with its caloric 
 before the rest, expands or contracts, and 
 destroys the cohesion. 
 
 “ Next to these come dried woods. Mr. 
 Meyer* has made a set of experiments on 
 the conducting power of a considerable 
 number of woods. The result may be 
 seen in the following Table, in which 
 the conducting power of water is sup¬ 
 posed = 1. 
 
EFFECTS OF HEAT, 
 
 89 
 
 BODIES. Conducting 
 
 Water -..=1.00 
 
 Diaspyrus ebenum, or ebony =2.17 
 
 Pyrus malus, or tbe common apple-tree ... =2.74< 
 
 Fraxinus excelsior, or the ash-tree ----- =3.08 
 
 Fagus sylvatica, or the beech tree ----- =3.21 
 Carpinus betulus, or common hornbeam - - - =3.23 
 Prunus doinestica, or common plum tree - - - =3.25 
 Ulmus, or the elm - -- -- -- -- =3.25 
 Quercus robur pendunculata, or common oak - =3.26 
 
 Pyrus communis, or the common pear tree - - =3.32 
 
 Betula alba, or the common birch tree - ■ - =3.41 
 Quercus robur sessilis, the low growing oak - =3.63 
 
 Plnus picea, or yew leaved fir - - - - - - =3.75 
 
 Betula alnus, or the alder tree ------ =3.84 
 
 Pinus sylvestris, or the wood pine.=3.86 
 
 Pinus abies, or the European spruce fir - - - =3.89 
 Tilea Europaea, or the European lime tree - - =3.90 
 
 Charcoal is also a bad conductor: 
 According to the experiments of Morveau, 
 its conducting power is to that of fine 
 sand :: 2 : 3*. Feathers, silk, wool, and 
 hair, are still worse conductors than any 
 of the substances yet mentioned. This is 
 the reason that drey answer well for 
 articles of clothing. They do not allow 
 'the heat cf the body to be carried off by 
 
 ' Ann. de Chim.; 
 
 M 
 
90 
 
 EFFECTS OF HEAT. 
 
 the cold external air. Count Rumford 
 has made a very ingenious set of experi¬ 
 ments on the conducting power of diese 
 substances *. He ascertained that their 
 conducting power is inversely as the fine¬ 
 ness of their texture. 
 
 “ The conducting power of liquid bodies 
 has not been examined with any degree of 
 precision. I find, by experiment, that the 
 relative conducting powers of mercury, 
 water, and lintseed oil, are as follows: 
 
 I. Ejual Bilh, 
 
 Water ------ =1 
 
 Mercury ----- =2 
 
 Lintseed oii . - - - =1.111 
 
 II. Equal Wcighit, 
 
 Water ------ —1 
 
 Mercury ----- =4.8 
 
 Lintseed oil - - - - =1.085 
 
 “ As bodies conduct caloric in conse¬ 
 quence of their affinity for it, the inequality 
 of their conducting power is a demonstra- 
 
 ♦ Phil. Trans. 1792. 
 
EFFECTS OF HEAT. 91 
 
 tion that their affinities for caloric are also 
 unequal. It is probable that their affinity 
 for caloric is in all cases the inverse of 
 their conducting power. If, therefore, we 
 were in possession of the relative conduct¬ 
 ing powers of bodies, the inverse of that 
 would give us the affinities in absolute 
 numbers. Thus the affinity of 
 
 Water is - . , =I . . . =1 
 Mercury ... - - =0.208 
 
 Lintseed oil - - =y.'#st " ' =0.921 * 
 
 75. ‘‘ When a fluid is heated at its 
 surface, the heat gradually and slowly 
 descends in the same manner as along a 
 solid; and fluids seem to have a difference 
 in their conducting power, analogous to 
 that of solids. But when the heat is 
 applied to the bottom of a vessel contain¬ 
 ing a fluid, the case is very different, the 
 heated particles of the fluid, in conse¬ 
 quence of their diminished specific 
 gravity, form an ascending current, and 
 rise to the surface, communicating a 
 
 ” Thomson's Chera. voh i. p. 527—3S0, 
 
92 
 
 EFFECTS OF HEAT. 
 
 portion of heat in their ascent to the 
 contiguous particles, but still retaining 
 a superiority of temperature; so that the 
 increase of temperature in the mass is 
 first observed at tbe surface, and is 
 constantly greatest there till commence¬ 
 ment of ebullition in liquids, at which 
 period the temperature is uniform. The 
 conducting power of fluids then arises 
 from two distinct sources: the one is the 
 same as solids, namely, a gradual progress 
 of theheatfrompardcle to particle,exclusive 
 of any motion of the particles themselves; 
 the other arises from the internal motion 
 of the particles of the fluid, by which the 
 extremes of hot and cold are perpetually 
 brought into" contact, and the heat is thus 
 diSused with great celerity. The latter 
 source is so much more eflectual than the 
 former, that some have been led, though 
 without sufficient reason, to doubt the 
 existence of the former, or that fluids 
 do convey heat in the sarne manner as 
 solids. 
 
EFFECTS OF HEAT. 
 
 93 
 
 “ Nothing appears then, but that the 
 comnaunication of heat from particle to 
 particle, is performed in the same way in 
 fluids as in solids; the rapidity of its 
 
 diffusion in fluids, is to be ascribed to 
 
 a hydrostatical law. But there is another 
 method by which heat is propagated 
 through a vacuum, and through elastic 
 fluids, which demands our particular 
 notice. By this we receive the heat of 
 the sun, and by this, when in a room, we 
 receive the heat of an ordinary fire. It is 
 called the radiation of heat; and the heat so 
 propelled, is called radiant heat 
 
 '76. “ The activity of these rays, says 
 Count Rumford, may be shown in dif¬ 
 ferent ways, but in no way, in a more 
 striking manner, than by the following 
 simple experiment. When the fire burns 
 bright upon the hearth, let the arm be ex¬ 
 tended in a straight line towards the centre 
 of the fire, with the hand open, and all the 
 fingers extended and pointing to the fire. 
 
 “Dalton, p. JOO, 101, 102. 
 
EFFECTS OF HEAT. 
 
 If the hanri is not nearer the fire than the 
 distance' of two or three yards, except the 
 fire be very large indeed, the heat will 
 scarcely be perceptible; but if without 
 moying the arm, the wrist be bent upwards, 
 so as to present the inside, or flat of the 
 hand perpendicular to the fire, the heat 
 will not only be very sensibly felt, but if 
 the fire be large, and if it burns clear and 
 bright, it will be found to be so intense 
 as to be quite insupportable 
 
 77. “ Till lately, we have been used to 
 consider the light and heat of the sun, as 
 the same thing. But Dr. Herschel has 
 shown, that there are rays of heat pro¬ 
 ceeding from the sun, which are separable 
 by a prism, from the rays of light; they 
 are subject to reflection like light and to 
 refraction, but in a less degree, which is 
 the cause of their separability from light. 
 The velocity of radiant heat is not known, 
 but it may be presumed to be the same 
 
 as that of light, till something appears 
 
 • Rnniford’s Essays, vol, ii. p. 47. 
 
EFFECTS OF HEAT. 
 
 95 
 
 to the contrary. An ordinary fire of red 
 hot charcoal, or, indeed, any heated body, 
 radiates heat, which is capable of being 
 reflected to a focus, like the light and heat 
 of the sun; but it should seem not to be 
 of sufficient energy to penetrate glass, or 
 other transparent bodies, so as to be re¬ 
 fracted to an efficient focus 
 
 78. “ Dr, Hoffmann, appears to have 
 been the first that collected the invisible 
 heat of a stove into a focus, by the reflec¬ 
 tion of one or more concave mirrors. 
 BulFon, Saussure, Pictet, and Mr. King, 
 made afterwards similar experiments on 
 the heat of a plate of iron, and of a vessel 
 of boiling water f.” 
 
 79, Professor Lesslie, has lately ascer¬ 
 tained and published in his “ Inquiry on 
 Heat,” several new and important facts, 
 relative to the radiation I of heat. Some 
 
 * Dalton, p. 101 and 102 . f Young’s Nat. Phil. p. 637. 
 
 I Professor Lesslie calls this tlie pulsation of heat. The term 
 radiation, not being applicable according to his theory. 
 
96 
 
 EFFECTS OF HEAT. 
 
 of the principal of these facts, it will be 
 proper here to mention; but I shall first 
 endeavour to give some idea of the instru¬ 
 ments which he used. 
 
 These were concave mirrors of tin-plate, 
 about 14 inches in diameter, and tin-plate 
 cannisters of different sizes, one side of 
 which was kept clean and bright, the 
 opposite was covered with writing paper, 
 or painted with lamp black; the other 
 sides were left for miscellaneous service. 
 With these was employed an ingeniously 
 constructed and delicate air thermometer, 
 than which nothing could be more simple 
 and commodious, and for the invention of 
 which, the philosophical world are indebted 
 to Mr. Lesslie. It is thus constructed. 
 
 80. “ Two glass tubes of unequal 
 lengths, each terminating in a hollow ball, 
 
 and having their bores somewhat widened 
 at the other ends, a small portion of 
 sulphuric acid tinged witli carmine being 
 introduced into the ball of the longer 
 tube, are joined together by the paeans 
 
EFFECTS OF HEAT. 
 
 97 
 
 of a blow-pipe, and afterwai’ds bent into 
 nearly tbe shape of tlie letter U, the one 
 flexure bemg made just below the joining, 
 where the small cavity facilitates the adjust¬ 
 ment of the instrument, which, by a little 
 dexterity, is perfonned by forcing with 
 the heat of the hand a few minute globules 
 of air from the one ball into the other. 
 The balls are blown 'as equal as the eye 
 can judge, and from four-tenths to seven- 
 tenths of an inch in diameter. The tubes 
 are such as are drawn for mercurial 
 thermometers, only witli wider boi’es; 
 that of the short one, and to which the' 
 scale is affixed, must have an exact calibre 
 of a fiftieth or a sixtieth of an inch; the 
 bore of the long tube need not be so re¬ 
 gular, but should be visibly larger, as the 
 coloured liquor will then move quicker, 
 under any impression. Each leg, of the 
 instrument is from three to six inches in 
 height, and the balls are from two to four 
 inches apart. The lower portion of the . 
 syphon is cemented at its middle to a 
 slender wooden pillar inserted into a 
 round or square. bottom, and such that 
 N 
 
98 EFFECTS OF HEAT. 
 
 the balls stand on a level with the centre 
 of the speculum. A moment’s attention 
 to the construction of this instrument will 
 satisfy us that it is affected only by the 
 (T^erence of heat in the corresponding 
 balls, and is calculated to measure such 
 difference with peculiar nicety. As long 
 as both balls are of the same temperature, 
 whatever this may be, the air contained 
 in the one will have the same elasticity as 
 that in the other, and consequently the 
 intercluded coloured liquor, being thus 
 pressed equally in opposite directions, 
 must remain stationary. But if, for in¬ 
 stance, the bail which holds a portion of 
 the liquor be warmer than the other, the 
 superior elasticity of the confined air will 
 drive it forwards, and make it rise in the 
 opposite branch above the zero, to an 
 elevation proportional to the excess of 
 elasticity or of heat The interval be¬ 
 tween freezing and boiling water being 
 disdnguished into an hundred equal parts, 
 called centigrade^ each of these subdivided 
 decimally, constitute the degrees which I 
 employ, .and which, following up the same 
 
EFFECTS OF HEAT. 
 
 system of nomenclature, would be termed 
 milligrade”. See Fig. 6, Plate 1. 
 
 81. “ I may notice a simple improve¬ 
 ment, or modification of the differential 
 thermometer, which fits it for est imatin g 
 with nice precision,, the intensity of the 
 diffuse radiations of heat. It has still the 
 form represented by Fig. 2, * only the 
 ball of the graduated stem is completely 
 gilt or enamelled with gold. But the two 
 balls exposed to the same influence, will 
 now receive very different impressions, 
 and the excess of energy, which the in¬ 
 strument marks, must, therefore, amotmt 
 nearly to seven-eighths of the whole vi¬ 
 bratory tide. Hence, it will measure the 
 quantities of heat that are continually 
 thrown from the fire into a room. ‘ We 
 can thus calculate, with equal ease and 
 certainty, the ralative advantages arising 
 from various constructions of chimniesf.” 
 
 * Mr. LesHe^s Fig, 2, is the same as Fig, 6', Flate 1, of this Essay. 
 
 f Leslie on Heat, p. 9—11, 561. 
 
100 
 
 EFFECTS OF HEAT. 
 
 82. Mr. Leslie has also applied this 
 mstrument, in a very simple and ingen¬ 
 ious manner, by covering one of the balls 
 ■with thin silk, and moistening it tO aCt 
 as a hygrometer, or instrument for mea¬ 
 suring the degree of, moisture in the 
 atmosphere. An instrument of the kind 
 has long been ■wanted in the cotton and 
 other manufactures. Respecting Mr. Dal¬ 
 ton’s hygrometer, as also those of Bereze- 
 lius, and Mr. Gough, the reader will find 
 information in the Philosophical Magazine, 
 vol. sxxiii. p. 39,177, 
 
 83. The following ai'e some of the 
 principal facts, which were discovered or 
 confirmed by Professor Leslie. 
 
 ist, If a given vessel be filled with hot 
 water, the quantity of heat which radiates 
 fi-om it, depends chiefly upon the nature 
 of the exterior surface df the vessel. 
 Thus, if a canister of tinned iron be the 
 vessel, then a certain quantity of heat 
 radiates from it; if the said vessel be co- 
 ■rered with black paint, paper, glass, &c. 
 
EFFECTS OF HEAT. 101 
 
 it will then radiate 8 times as much heat 
 in like circumstances 
 
 84. 2d, “ If the bulb of the thermometer 
 
 be covered with tin-foil, the impression of 
 the radiant heat is only ^ of that upon the 
 glass surface. 
 
 85. 3d, “ A metalic mirror reflects 10 
 times as much heat from an ordinary fire, 
 or from any heated body, as a similar 
 glass mirror does. This last is found to 
 reflect the heat from its anterior smTace, 
 and not from the ^ quick-silvered one, 
 which is the most essential in reflecting 
 solar light, and heat. Here then is a 
 striking difference between solar and 
 culinary heat. 
 
 '* When one side of a tin-plate canist 
 another with writing paper, a third wit 
 or covered with tin-foil, the differeni 
 Blach side was exposed to the specului 
 Writbg paper ------- 
 
 Tin-plate, or tin-foil - - - - - 
 
 2d with lamp black, 
 the fourtli left bare, 
 
102 
 
 EFFECTS OF HEAT. 
 
 “ From these facts it appears, that 
 metals and other bodies which are emi¬ 
 nently disposed to r^ect radiant heat, are 
 not disposed to ahorb it in any remark¬ 
 able degree; whereas black paint, paper, 
 glass, &c. are disposed to ahsorh it, and 
 consequently to radiate it again in proper 
 circumstances,” 
 
 86. 4th, “ The heat radiating from hot 
 water, does not seem capable of being 
 transmitted through glass like the solar 
 
 87. 5th, “ When a heated body is 
 whirled through the air, the additional 
 cooling effect is directly proportional to 
 the velocity 
 
 88. Mr. Dalton infers from his experi¬ 
 ments, contrary to the results obtained 
 by Mr. Leslie, that the same law of 
 progressive cooling (viz. that “ the tempera¬ 
 ture descends in geometrical progression to equal 
 
 Dalton’s Chem. PhU. pages, 103,104,105. 
 
EFFECTS OF HEAT. 
 
 103 
 
 increments of time"^”) applies to a metalic 
 as well as to a vitreous surface f. The 
 surface, however, materially affects the 
 whole time which is occupied in cooling. 
 
 89. “ After a long and intricate, but 
 ingenious investigation, Mr. Leslie finds 
 the cooling power of the air upon a hol¬ 
 low sphere, six inches in diameter, and 
 filled with boiling water, to be as follows; 
 namely, in each minute of time, the fluid 
 loses the following fractional parts of its 
 excess of temperature, by the three distinct 
 sources of refrigeration in the air under¬ 
 mentioned. 
 
 “ By abduction, that is, the proper con¬ 
 ducting power of air, the 524th, 
 
 “By recession, that is, the perpendicular 
 current of air excited by the heated body,, 
 the hx2i'715th. , 
 
 •Dalton, p. 111. 
 
 f “ The term surface is used tliroughout this discourse, in its physical 
 and not its mathematical acceptation. 1 employ it to signify a stratum, 
 of matter of a certain finite depth, yet of such extreme tenuity as almost 
 to escape the cognizance of the senses. Lesh's on Heat, p. 85.” 
 
104 EFFECTS OF HEAT. 
 
 “ 'Qj pulsation, or radiation, the 2533d part 
 from a metalic surface, and eight times as 
 much, or the SlTth part from a surface of 
 paper. • It should be observed, that Mr. 
 Leslie contends that air is instrumental in 
 the radiation of heat, which is contrary to 
 the received opinion*.” 
 
 In the above fractions, Mr. Dalton does 
 not acquiesce, and after detailing his own 
 experiments, he proceeds as follows; 
 
 “ It will be proper now to inquire into 
 the cause of die difference in the times of 
 cooling, arising from the variation, of 
 surface. Mr. Leslie has shown the sur¬ 
 face has no Influence upon the time of 
 cooling, when immersed in water; it 
 should seem then, that the difference of 
 surfaces in the expenditure of heat, arises 
 from dieir different powers of radiation 
 solely; indeed, Leslie has proved by direct 
 experiments, that the heat radiating from a 
 vitreous or paper surface, is 8 times as 
 
 •* Dalton, page lOS. 
 
EFFECTS OF HEAT. 
 
 105 
 
 great, as that from a metallic surface. 
 Taking this for granted, we can easily 
 find the portions of heat dispersed by 
 radiation, and conducted away by the 
 atmosphere. For let 1 denote the quan¬ 
 tity of heat conducted away by the at¬ 
 mosphere, from a vitreous or metallic, 
 surface, in any given small portion of 
 time, and x the quantity radiated from a 
 nietallic surface in the same timej then 8 x 
 will be the quantity radiated from a vitre¬ 
 ous surface in that time; and from the 
 result of the last experiment we shall have 
 2:3:: 1 + x : 1 + 8 x-, whence 2 + 16 x— 
 3+3 X, and x=^-, this gives 1,V for the 
 whole heat discharged by metal, and liV 
 for that discharged by glass in the same 
 time, where the unit, expresses the part 
 conducted, and the fraction the part radi¬ 
 ated. That is, from a metallic surface, 13 
 parts of heat are conducted away by the 
 air, and 1 part radiated; from a vitreous 
 surface, 13 parts are conducted, and 8 
 parts radiated, in a given time. 
 
 O 
 
,106 EFFECTS OF HEAT. 
 
 “ The quantity of heat discharged by 
 radiation, from the most favourable sur¬ 
 face, therefore, is probably not more than 
 4 of the whole, and that conducted away 
 by the air not less than .6—^Mr. Leslie, 
 however, deduces .57 for the former, and 
 .43 for the latter, because he found the 
 disproportion in the times of cooling of 
 vitreous and metallic surfaces, greater 
 than I find it in the lower part of the 
 scale.” 
 
 “ The obvious consequences of this 
 doctrine, in a practical sense, are;” 
 
 “ 1st, In every case wheiu heat is re¬ 
 quired to be retained as long as possible, 
 the containing vessel should be of metal, 
 ■with a bright clear smlace.” 
 
 “ 2d, Whenever heat is required to be 
 given out by a body with as much celer¬ 
 ity as possible, the containing vessel if of 
 metal, ought to be painted, covered with 
 paper, charcoal, or some animal or vegi- 
 table matter; in which case the heat given 
 
EFFECTS OF HEAT. 
 
 107 
 
 eut, will be 3 parts for 2 from a metallic 
 surface For it is to be recollected, that 
 the nature of the surface affects only that 
 part of the heat which is radiated. The 
 other two causes of refrigeration, called, 
 by Mr. Leslie, abduction and recession^ or 
 which come together under the- more 
 usual name of combined heat., remain the 
 same whatever be the nature of the 
 surface. 
 
 90. Mr. Leslie, in an early part of his ' 
 inquiry, having, as we saw (Art. 83.) ascer¬ 
 tained that bodies differ widely in their 
 power of projecting, absorbing, and re¬ 
 flecting heat, instituted a set of experi¬ 
 ments, with a view to ascertain the limits 
 of tills variation. From these experiments, 
 he found that the chemical qualities of the 
 heating surface, have a. considerable influ¬ 
 ence, as will appear from the following 
 summary of the results of his experi¬ 
 ments. 
 
 • Dalton’s Cheni. Phil, IIS, US, 117. 
 
108 
 
 EFFECTS OF BEAT. 
 
 The standard effect of a coat of lamp-black being - 100 
 The effect of bright surfece of tin ......12 
 
 Iton or steel is as - 15 
 
 Mercury above - -.... .....-20 
 
 All oxydes act more powerfully as they 
 recede from a metallic state. 
 
 vllean lead, but rough, being as-- - - -- -19 
 
 • Lead tarnished by exposure to the air - - - - - 45 
 
 Black lead or plumbago - ...-75 
 
 Red lead, or minium as .-..--..-80 
 
 Dry size, or isinglass - -- --.80 
 
 Sealing wax and rosin are nearly equal to paper, which is - 98 
 Ice.85 
 
 The polish, where not naturally great, 
 diminishes its action. Thus, tin-plate 
 when hammered, (which Mr. Leslie calls 
 planished tin,) its power to propagate heat 
 is only half that of ordinary , tin-plate. 
 The roughening of glass, however, does 
 not increase its power of projecting heat. 
 
 That of tin is doubled by covering it 
 with stria or furrows made in one direc¬ 
 tion, by a file or toothed-plane. This 
 remarkable effect cannot be owing to the 
 
EFFECTS OF HEAT. 
 
 109 
 
 greater surface exposed, because the in¬ 
 crease of surface is exactly counteracted 
 by the increase of obliquity, according to 
 a law which Mr. Leslie established by 
 experiment; and, besides, it is found that 
 cross furrows by striating the surface in 
 the other direction, nearly destroys the 
 eflFect of those first made 
 
 The thickness of the radiating surface 
 has a great influence on its powers of 
 action, a thin film of isinglass produces a 
 radiation as 26, a thick film as 42, when 
 the thickness exceeds the thousandth part 
 of an inch, any subsequent increase does 
 not augment its action. 
 
 Mr. Leslie' is of opinion, that these 
 differences in projective power, may be 
 resolved into the variations of the bodies, 
 as to hardness and softness, and shows 
 that the addition of moisture and still 
 more of a mucilaginous substance, con¬ 
 siderably augments the action of a sur¬ 
 face painted black. 
 
110 EFFECTS OF HEAT. 
 
 Mr. Leslie doiibts whether the quality 
 of colour exerts any influence at all, in 
 modifying the projective and absorbent 
 powers of bodies. 
 
 The various reflecting powers of differ¬ 
 ent surfaces, bears some inverse ratio to 
 their absorbent and projective powers, 
 although many circumstances occur to 
 prevent this ratio from being expressed 
 by one universal law. 
 
 91. Mr. Leslie having investigated the 
 
 various circumstances which ‘affect the 
 progress of the cooling of bodies, when 
 the enclosing boundary is considered a 
 mere physical surface, (Art. 88.) but where 
 the surface of a body is defended by a 
 covering of slow conducting materials, 
 the process of refrigeration, is retarded in 
 proportion to the thickness of the exterior 
 coat. On this principle depends the utility 
 of cloathing, whether natural or artificial, 
 also that of covering steam tubes witli 
 slow conducting materials to prevent the 
 dissipation of heat.- But it requires a 
 
EFFECTS OF HEAT. Ill 
 
 considerable thickness of such materials, 
 to counteract the effect of the physical sur^ 
 face in propagating heat. Thus, Mr. 
 Leslie informs me, that he found it re¬ 
 quired three plies of flannel to overcome 
 its radiating power. 
 
 92. “ A fluid of such extreme rarity as 
 air, if confined round a heated body, must 
 like those spongy substances, have a 
 decided influence to retard the operation 
 of cooling. And this property is most 
 distinctly perceived, though on a very 
 limited scale. If a series of hollow 
 cyliudiical vessels be constructed of very 
 thin brass, to fit into- one another like a 
 nest of boxes, the first or smallest, filled 
 with boiling water, and with a fine ther¬ 
 mometer inserted, being enclosed in each 
 of die rest consecutively, according to the 
 order of their width, and kept equally 
 separate from the sides and bottom, by 
 resting against protuberant points or a 
 slender chequered ring; on plunging the 
 canister with its adapted case, in a tub 
 of water, the rate of cooling will be found 
 
112 
 
 EFFECTS OF. HEAT. 
 
 at every successive trial, regularly to 
 diminish till the space of iutercluded air 
 comes to exceed a quarter of an inch^ vrhen 
 -the effect wiU be reduced to about a six¬ 
 teenth part. Beyond this limit scarcely 
 any farther decrease is observed, there 
 now being room sufficient to allow that 
 active fluid to develope its mobility, 
 which fully compensates for the increas¬ 
 ing distance of communication. A limit 
 so narrow, must evidently preclude the 
 great majority, of instances that would 
 occur. The property of confined air to 
 retard the progress of cooling, is, there¬ 
 fore, founcied on a principle not quite 
 obvious, and not hitherto explained. By 
 employing a series of concentric cases, or 
 septa^ this effect is wonderfully height¬ 
 ened. Yet a subject in itself so curious, 
 and of such vast importance in the econ¬ 
 omy of heat, has been generally over¬ 
 looked, or only treated in a vague and 
 superficial manner. As I purpose to 
 consider it with some attention, 1 shall, 
 for the sake of clearness, divide it into 
 three branches: 1st, when the surface of 
 
EFFECTS OF HEAT. 
 
 the internal canister, and its several cases 
 are metallic; 2d, when those surfaces are 
 all painted, or consist of glass; and 3d, 
 when they are composed partially of both 
 sorts. 
 
 93. “ 1st, When all the surfaces by 
 which the included or exterior air is 
 bounded, are metallic. 
 
 “ Suppose the canister so large that its 
 surface may be regarded as equal to that 
 of the exterior case, vv^hich is separated 
 from it, only by a narrow space. After 
 an equilibrium is attained, the case will 
 receive and discharge heat exactly in the 
 same proportion; it must, therefore, be 
 just as much hotter than the external, as 
 it is colder than the included air. But 
 this confined portion, will have evident¬ 
 ly the mean temperature of its bound¬ 
 ing sides. Consequently, reckoning the 
 heat of the room as a standard, the tem¬ 
 perature of the outer case, must be equal 
 to half the difierence between itself and 
 the temperature of the canister, or equal 
 P 
 
114 
 
 EFFECTS OF HEAT. 
 
 to one-third of this whole quantity. 
 Hence, the canister under the shelter of 
 its case, will cool three times slower than 
 if it were exposed naked. Thus, when 
 the central heat is 30°, that of the exterior 
 surface will be 10°, and their arithmetical 
 mean, or 20°, will be the temperature of 
 the confined stratum of air. Therefore, 
 the rate of internal communication which 
 cools the one surface in the same degree 
 as it heats the other, will be as 10°, or 
 equal to the discharge into the free sur- 
 rotmding atmosphere. 
 
 “ Imagine a second case to be now 
 added. The mean temperature of the air 
 which that contains, is equal to its differ¬ 
 ence from the mean temperature of the 
 air Included within the .-first case; and 
 either of these measures is equal to half 
 the excess of the central heat above this 
 last mean. Hence, the outmost case will 
 have only one-fifA part of the tempera¬ 
 ture of the canister; and, consequently, by 
 the intervention of a double case, its rate 
 of cooling Is diminished five times. For 
 
EFFECTS OF HEAT. 
 
 115 
 
 the sake of illustration, let the temperature 
 of the central mass be 25°, then that of 
 the first case will be 15°, and that of the 
 second case 5°, the mean temperature of 
 the inner stratum of air will be 20°, and 
 that of the outer one 10°, the surface of 
 tlie canister will regularly discharge a 
 portion of heat as 5°, the next septum will 
 receive and deliver the same to the con¬ 
 tiguous air; and the external case will 
 absorb this portion, and finally discharge 
 it into the air of the apartment. 
 
 “ Pursuing the same mode of reasoning, 
 it would be easy to show, that, with three 
 concentric cases, the canister would cool 
 seven times more slowly; and with four 
 such cases, nine times more slowly. In 
 general, the degree of diminution is equal 
 to double the number of cases increased 
 by one, or the number of surfaces con¬ 
 cerned: it is hence represented by the 
 progression of the odd numbers, 3, 5, 7, 
 9, 11, 13, &c. , 
 
116 EFFECTS OF HEAT. 
 
 “ This result will appear sufficiently 
 accurate when -the canister is. o£ consid¬ 
 erable size, and tlie cases not too widely 
 disjoined; for instance, if the canister 
 exceeds a foot in diameter, and tlie inter¬ 
 vals between the cases are each of them 
 
 not more than half an inch 
 
 EXPERIMENT. 
 
 “ A cylindrical canister of planished 
 tin, two inches in diameter and equal 
 height, filled with boiling water, took 
 117' to cool, from 30° to 10°; but en¬ 
 closed within a similar canister of fom' 
 inches in diameter, it required 176' to 
 make the same descent. Another cylin¬ 
 drical canister of four inches, and which 
 took 156' to cool from 20° to 10°, re¬ 
 quired, 356', when cased with a similar 
 one of five inches; yet, the interval being 
 filled with flour, the effect was performed 
 in 324'. And a square canister of three 
 inches, that cools from 20° to 10° in 117', 
 took 335' to perform the same effect, after 
 
 * Leslie on Heat, pages 373—378. 
 
EFFECTS OF HEAT. 117 
 
 it was enclosed within two similar cases 
 of four and five inches 
 
 94. “ 2d, The next division of the pro¬ 
 blem is, where the canister and its sur¬ 
 rounding cases are painted or vitreous. 
 
 This condition will be found to alter 
 materially the proportion of the result. 
 When two such surfaces with unequal 
 degrees of heat, are made to front each 
 other, they will not, like metallic plates, 
 act the same as if they were quite insulat¬ 
 ed; but must, by their pulsatory energies, 
 exert a mutual infiuence to accelerate the 
 progress towards au equilibrium. If their 
 visual magnitude be very considerable, 
 or their extent great in comparison of 
 their distance, almost the whole of those 
 opposite dispersive pulsations, will be 
 intercepted and received on both sides. 
 But, with a moderate difierence of tem¬ 
 perature, the vibratory discharge,, consti¬ 
 tutes very nearly the half of tlie ordinary 
 measure of communication. Therefore, 
 
 * Pages 380, SSI. 
 
118 
 
 EFFECTS OF HEAT. 
 
 the vitreous or painted surfaces must emit 
 or absorb heat, one-half faster than if they 
 were removed beyond each others sphere 
 of action, but accompanied by the same 
 intercluded atmosphere. 
 
 “ If the one surface be completely en¬ 
 compassed by the other, it is evident, that 
 the exterior will receive all the diverging 
 pulsations; and, if the interior be not dis¬ 
 proportionately small, it must, in its turn, 
 intercept those which are reciprocally 
 convergent 
 
 95. “ 3d, The last branch into which 
 the problem divides itself, is, that where 
 vitreous and metallic surfaces are pro¬ 
 miscuously combined. But as such pos¬ 
 sible combinations must, evidently, be 
 very numerous, I shall select only their 
 principal varieties. 
 
 “ Suppose a painted canister is included 
 within a bright tin case. If the reflective 
 
EFFECTS OF HEAT. 
 
 119 
 
 power of the internal surface of the case 
 were absolutely complete, the progress of 
 refrigeration would be exactly the same 
 as if the canister had a metallic, lustre; - 
 for the discharge of heat by pulsation 
 would then be rendered altogether abor^ 
 tive, being constantly sent. back from the 
 case to its source, and there re-absorbed. 
 The effect would thus be comparatively 
 much greater than in any of the preced¬ 
 ing instances. However, the defective 
 reflection, or partial absorption of the tin, 
 sensibly modifies the result. It is obvi¬ 
 ous, that the mean temperature of the 
 intercluded air, will be determined in the 
 same manner as before. But, wliile a 
 polished metallic surface emits nine parts 
 of heat, a painted one disperses sixteen. 
 Of the sixteen parts, therefore, which the 
 canister is capable of discharging, no 
 more than ten prove really effective, the 
 additional part only being .absorbed by 
 the inner surface of the case.. Hence, the 
 temperature of the exterior surface, must 
 be somewhat greater than the mean in¬ 
 ternal difference, to enable it to disperse 
 
120 - EFFECTS OF HEAT. 
 
 its invigorated accesions of heat into free 
 
 space. 
 
 “ Let the position be now reversed, the 
 surface of the canister being clear, and its 
 exterior case painted on both sides. This 
 case therefore, absorb at its inner 
 
 surface, ten parts of heat, of which the 
 canister makes an effective discharge; but, 
 with the same difference of temperature, 
 it would disperse sixteen parts into the 
 free external atmosphere *. 
 
 “ It would be superfluous to prosecute 
 this subject any farther. The examples 
 which have been chosen are sufficient to 
 explain the varying mode of investigation. 
 When several cases are employed, alter¬ 
 nately vitreous and metallic, the effect is 
 nearly the same as if they were all metallic; 
 but the general - influence, will depend 
 chiefly on the quality of the outmost sur¬ 
 face. For the same reason, the vitreous 
 or painted surfaces, will have much less 
 
 •Pages 390, 391, 393. 
 
EFFECTS OF HEAT. 121 
 
 power to retard the process of cooling 
 when they lie adjacent, than when they 
 are interspersed *. 
 
 “ With equal facility, may be deter¬ 
 mined the progress of refrigeration, which 
 obtains on the immersion of the apparatus 
 in a liquid mass. Since the discharge of 
 heat by external pulsation is now pre¬ 
 cluded, the nature of the extreme bound¬ 
 ary, will have no influence whatever on 
 the measure of effect. This result must 
 depend almost entirely on the quality, the 
 position, and the number of the interior 
 surfaces f, 
 
 “ A cylindrical canister of planished tin, 
 three inches in diameter and height, and 
 which in still air takes 117' to cool, from 
 20° to 10° would require 249' if in¬ 
 cluded regularly within a similar cylinder 
 of four inches, but only 185' if the whole 
 were immersed in a tub of water. The 
 same canister when painted, would, in a 
 
 • Page 394. t F“g« S9S. 
 
 Q 
 
122 
 
 EFFECTS OF HEAT. 
 
 close room, cool in 61', or, surrounded 
 with, its case likewise painted, in 98', and 
 both plunged in water would take only 
 64'. 
 
 “ In all these examples, the canister and 
 its several cases are regularly separated 
 from each other by intervals of half an 
 inch. If the divisions approach nearer, 
 their effect soon becomes altered; for the 
 successive strata of intercluded air as they 
 diminish in thickness, lose in some degree 
 their internal mobility, and begin passively 
 to transmit heat like a solid mass. When 
 the terminating surfaces mutually approx¬ 
 imate, not only is the fluidity of the thin 
 shells of air proportionally cramped, but 
 the power of communication is likewise 
 invigorated by the shortness of the pas¬ 
 sage, and consequently the quicker grada¬ 
 tion of temperature. On both these 
 accounts, therefore, the quantity of trans¬ 
 mission -will increase with most rapid 
 progress, as the septa contract their Ihnits. 
 Thus, a cylindrical tin canister of three 
 inches in diameter and height, placed 
 
EFFECTS OF HEAT. ' 123 
 
 within a similar one of four inches, will 
 cool about one-sixtieth part faster, if 
 shifted from its position in the middle to 
 a quarter of an inch from the bottom; 
 and nearly one-nintieth part still faster, 
 when advanced only an eight of an inch 
 from that boundary. Hence, we rnay 
 compute that a stratum of air one quarter 
 of an inch thick, transmits through its 
 substance, about a sixth part of the heat 
 which it is fitted to communicate in the 
 ordinary mode, and if reduced to half this 
 thickness, it will deliver nearly equal' 
 shares in both ways. 
 
 “ But to discover more accm'ately the 
 progress of this internal transmission, I 
 procured another intermediate cylinder of 
 tin, with a moveable lid and three inches 
 and three quarters in diameter. The 
 three inch canister enclosed within this, 
 had its rate of cooling reduced to 7-15ths. 
 But calculation gives . the difference 
 being only and, consequently, the 
 aberration or accelerating influence, cor¬ 
 responding to an interval of three-eights 
 
124 EFFECTS OF HEAT. 
 
 of an inch, must be extremely small. 
 The diameters of the cylinders are .as 4 
 and 5, and their surfaces as 16 and 25. 
 Therefore, the temperature of the internal 
 canister being denoted by unit, that of the 
 outer case is The mutual 
 
 difference is and hence, the canister 
 exceeds the temperature of the interjacent 
 by This fraction 
 
 ■will express the ordinary measure of com- 
 mtmication; but the actual discharge of 
 heat is 7-15ths, or -rrf, and, therefore, 
 or about the twelfth jrart of the whole, is 
 conveyed away through the stratum of ,air 
 by passive transmission. 
 
 “ When the intermediate cylinder was 
 included ■within the four inch one, their 
 interval being only the eight part of an 
 inch, the deviation appeared now to have 
 most rapidly increased. The rate of cool- 
 ing,instead of 17-47ths was only reduced to 
 17-26ths. -The opposite surfaces being as 
 225 to 256, orwery nearly as 15 to 17, 
 the temperature of the exterior one is 1-’- x 
 
EFFECTS OF HEAT. 
 
 125 
 
 i4=4i, and, consequently, the internal can¬ 
 ister must exceed the temperature of the 
 thin stratum of intercluded air by ii x 44= 
 ■114. This must denote the ordinary 
 discharge of heat, but the real consump¬ 
 tion is 44 =-Itts which is. nearly tiiple the 
 former. Therefore, when the shell of air 
 is only the eight of an inch in thickness, 
 of 31 parts of heat, 10 are carried off by 
 the. general process, and 21 by quiescent 
 communication. 
 
 “ But the close proximity, and still 
 more the partial contact of the canister 
 with its exterior case, has not merely a 
 negative influence to diminish the retard¬ 
 ation of cooling. It must actually accel¬ 
 erate the dispersion of heat, since, in 
 effect, it occasions an artificial enlarge¬ 
 ment of surface. A tin canister of two 
 inches square, will cool one-half slower, 
 when planted in the centre of a similar 
 one of four inches. But if it be made to 
 touch three sides of the case, it will cool 
 about three times faster than at first; for 
 these sides having the same temperature as 
 
126 EFFECTS OF HEAT. 
 
 the canister, and presenting twice its extent 
 of surface, must double the refrigerating 
 action, exclusive of the co-operation of 
 the remaining sides, which will add at 
 least one-half more. 
 
 “ To produce dieir proper effect, there¬ 
 fore, it is requisite that the cases should 
 be perfectly detached or insulated. The 
 retardation of the process of cooling, de¬ 
 pends entirely on the coldness of the 
 external surface. But metals conduct 
 heat so freely, that even a partial contact 
 might be sufficient to cause an almost 
 equal diffiision. If a roimd tin vessel of 
 a broad and rather flat shape, have a cap 
 fitted at each end, capable of being drawn 
 out to different small distances, the rate 
 of cooling will continue very nearly the 
 same, through all the gradations from the 
 position of absolute contiguity, till the 
 circular plates are separated by an interval 
 of perhaps three quarters of an inch, 
 'fhe narrow rms embracing the canister, 
 rapidly abstract heat, and convey it to the 
 prolonged boundaries. We, hence, see 
 
EFFECTS OF HEAT. 
 
 1S1 
 
 tlie defect of the ordinary form of pots 
 with double lids, designed for culinary 
 purposes 
 
 96. Many useful practical applications 
 of the principles here investigated might 
 be made, Mr. Leslie has proposed a 
 method of preserving ice, by enclosing it 
 within a number of tin canisters, and has 
 applied it for preserving liquids in a cool 
 state in warm climates; on the same prin- 
 
 ^ A late ingenious experimenter, who by the perspicuity and uieml 
 tendency of his writings, is deservedly a favourite of the public, has 
 advanced the paradoxical conclusion, that “fluids are non-conductors of 
 heat.” And this strange assertion from the celebrity of its author, has 
 been treated certainly with more attention and respect than it other-' 
 wise merited (Art. 7S.) If nothing more is meant, than that fluids as the 
 consequence of their extreme mobility, convey the impressions of heat 
 chiefly by means of their internal motions, the fact will not be disputed, 
 but though perhaps more distinctly announced, it can have very little 
 claim to originality. If the proposition, however, be taken in its strict 
 sense, it is most palpably erroneous. Were fluids absolutely incapable 
 of conducting heat, how could they ever become heated? Must we 
 suppose that the particles of a fluid can imbibe heat from those of a 
 solid, and yet not receive it from each otiter? On mixing cold with hot 
 water, a sort of heterogeneous compound will be formed, each molecnle 
 retaining without participation, its initial and peculiar temperature. 
 And where no such intermixture can take place, how could -water, for 
 instance, be heated by the contact of warm air? But the question really 
 deserves no serious discussion.” Leslie on Heat, pages SOT-a-dOS, 
 
EFFECTS OF HEAT. 
 
 dple, a good mode of protecting water- ' 
 pipes from freezing, would be to enclose 
 them in tin-plate tubes, leaving a space 
 of about an inch all round the leaden 
 pipes. It is also well worthy of consid¬ 
 eration, how far these principles might be 
 applied in the construction of the casing, 
 for the preservation of the heat of cylin¬ 
 ders of steam engines. Its advantages in 
 many situations of steam tubes is quite 
 obvious. 
 
 “ Befi'igeration of Bodies in various lands of 
 Elastic Fluids. 
 
 97. “ Bodies cool in very different times 
 in .some of the elastic fluids. Mr. Leslie 
 was the first, I believe, who noticed this 
 fact; and .he has given us the results of 
 his experiments on common air and hy- 
 drogeneous gas, of the common density, 
 and also rarefied in various degrees., I 
 made some experiments with a view to 
 determine the relative cooling powers of 
 the gases, the result of which, it may be 
 proper to give. 
 
KFFECTS OF HEAT. 
 
 129 
 
 Thermometer immersed in 7 cooled in 
 carbonic acid gas - - j 112 seconds. 
 —sulphuretted hydrogen, 1 
 .nitrous oxide, and ole- 100+ 
 fiant gas - - - - j 
 
 —com. air, azotic and ox- 7 
 
 —nitrous gas - _ - - 90 
 
 —carburet, hydrogen or 7 
 coal gas - - - - j 
 —^hydrogen ----- 40 
 
 “ Condensed air cools bodies more 
 rapidly than air of common density; and 
 rarefied air less rapidly, whatever be the 
 kind.—The results of my own experience 
 for common air were as follows: 
 
 CM& In 
 
 - - - 85 seconds. 
 
 - - 100 
 
 - - - 116 ' 
 
 - - 128 
 
 - - - 140 
 
 - - 160 
 
 - - - 170 
 
 R 
 
 Dcmiiy of the air, 
 2 - 
 1 - - 
 
130 
 
 EFFECTS OF HEAT. 
 
 “ The expenditure of heat by radiation, 
 being the same in hydrogenous gas as in 
 atmospheric air, we may infer, it is the 
 same in every other species of gas; and, 
 therefore, is performed independently of 
 the gas, and is carried on the same in 
 vacuo as in air. Indeed, Mr. Leslie him¬ 
 self admits, that the diminution of the 
 efiect consequent upon rarefaction is ex¬ 
 tremely small, which can scarcely be con¬ 
 ceived if air were the medium of radia- 
 
 “ The effect of radiation being allowed 
 constant, that of the density of the air 
 may be investigated, and will be found, 
 I believe, to vary nearly or accurately as 
 the cube root of the density ■ 
 
 ' Dalton, pages 115—120. 
 
EFFECTS OF HEAT. 
 
 ISI 
 
 SECTION VL . 
 
 Boiling or Ebullition. 
 
 98. The internal commotion excited in 
 any liquid, by the successive conversion 
 of the lower portions of the fluid into 
 vapour, and their violent effort under this 
 expansive and elastic form, is denominated 
 boiling or ebullition. Though usually it 
 is not necessarily produced by the applica¬ 
 tion of heat; for the removal of pressure 
 from the surface of the fluid, will produce 
 boiling in a liquid, previously in a quies¬ 
 cent state. Thus, if a vessel holding 
 warm water, be placed under the receiver 
 of an air punap, as the exhaustion pro¬ 
 ceeds and gradually withdraws the pres¬ 
 sure, at a certain point of rarefaction 
 boiling takes place. This point, therefore, 
 is not so unchangeable as the melting 
 point, for so far as is yet known, the 
 melting point of each kind of matter is 
 always the same. 
 
132 EFFECTS OF HEAT. 
 
 99. “ Every particular liquid has a fixed 
 point, at which this boiling commences, 
 (other things being the same,) and this is 
 called the boiling point of the liquid. 
 Thus, water begins to boil when heated 
 to 212°. It is remarkable, that after a 
 liquid has begun to boil, it never becomes 
 any hotter, however strong the fire be to 
 which it is exposed. A strong heat, in¬ 
 deed, makes it boil more rapidly, but does 
 not increase its temperature. This was 
 first observed by Dr. Hooke. 
 
 “ The following Table contains the 
 boiling point of a number of liquids. 
 
 Soiling Paint, n Sadies, Bailing Point, 
 
 Ether - - - - 98 1 Sulphuric acid - - 590 
 
 Ammonia . 140 ! Phosphorus - . - 5S4 
 
 Alcohol - . . . 176 I Oil of turpentine - 560 
 
 Water.212 Sulphur ..... 570 
 
 Muriat of lime . - 230 Lintseed oil - - . 600 
 
 Nitric acid .... 248 II Mercury .... 660 
 
 “ From the experiments of Professor 
 Robison, it appears, that in a vacuum all 
 liquids bod about 145° lower than in the 
 open air, under a pressure of 30 inches of 
 mercury; therefore, water would boil in 
 
EFFECTS OF HEAT. 1S3 
 
 vacuo at 67°, and alcohol at 34°. In a 
 Papin’s digester, the temperature of water 
 may be raised to 300°, or even 400°, 
 without ebullition. But the instant that 
 this great pressure is removed, the boiling- 
 commences with prodigious violence 
 
 100. “ The opposite influence of heat 
 and pressure on the constitution of fluids, 
 is well exhibited by a very simple, yet 
 striking experiment. Take a large thin 
 phial, and having warmed it gradually to 
 avoid tlie risk of cracking the glass, fill it 
 completely with boiling water, cork it 
 tight and expose it to a current of cold 
 air. As the water cools, it necessarily 
 contracts its volume, and leaving an 
 imperfect vacuity below the neck of the 
 phial, it hence becomes, to a considerable 
 degree, relieved from the load of atmo¬ 
 spheric pressure; it, therefore, soon begins 
 again to boil, nay, it will boil more brisk¬ 
 ly the faster, it cools; and this singular 
 appearahce, so contrary to our usual no- 
 
 • Thomson’s Chemistry, vol. 1st, p. 367. 
 
134 
 
 EFFECTS OF HEAT. 
 
 tions, may continue, perhaps, for the 
 space of half an hour, till the water has 
 grown as cold almost as the temperature 
 of the human body 
 
 101. From this cause of difference of 
 pressure, the boiling point differs with 
 the state of the atmosphere in the same 
 country, and is very different in different 
 countries. Thus, for instance, the boiling 
 point in Britain, under the mean pressure 
 of the atmosphere, is at 212° of Fahren¬ 
 heit, while at Mimich in Bavaria, it is 
 only 2091°, and at Quito in South Amer¬ 
 ica, much lower, owing to its great height 
 above the level of the sea, where the pres¬ 
 sure of the atmosphere is greatly reduced. 
 Hence, the boiling point has been em¬ 
 ployed to indicate the heights of places 
 above the level of the sea. . 
 
 102. “ The circumstances which precede 
 or accompany the phenomenon of boiling, 
 are best observed in a thin transparent 
 
 * Ree’s Cyclopedia, Art. Boiling^. 
 
EFFECTS OF HEAT. 
 
 135 
 
 flask, nearly filled witli water, and sus¬ 
 pended over - a lamp or a charcoal fire. 
 Numerous minute globules are seen col¬ 
 lecting from all points towards the sides, 
 and rising in a stream to the surface; 
 occasioned evidently by the discharge of 
 air, which is always in some proportion 
 combined with water. As the heat in¬ 
 creases, the liqmd particles , near the bot¬ 
 tom of the flask, suddenly burst into 
 steam, and shoot upwards; but in ascend¬ 
 ing through the . colder mass, they again 
 collapse, stop their progress and seeni lost. 
 Such alternate expansions and contrac¬ 
 tions, by throwing the fluid into a gentle 
 tremour, frequently causes a peculiar sort 
 of singing noise, which is rightly sup¬ 
 posed to betoken the approach of actual 
 boiling. This singing is more likely to 
 happen in the case where heat is applied 
 partially; for instance, if a tea-kettle be 
 placed at the side of the fire, since the 
 heat is then more slowly and unequally 
 diffused through the body of the water. 
 But after tire whole contents being fully 
 penetrated, are warmed up to the requisite 
 
136 
 
 EFFECTS OF HEAT. 
 
 degree of intensity, the steam, as fast as 
 it is formed, ascends continually, and 
 escapes unimpaired through the fluid, 
 which it, therefore, heaves with violent 
 agitation^.” 
 
 103. When heat is applied to the bot¬ 
 tom of a vessel containing water, the 
 heated particles nearest the bottom be¬ 
 comes specifically lighter, and, therefore, 
 mount upward and quickly dispose them¬ 
 selves in horizontal strata, according to 
 their respective degrees of temperature. 
 Thus, a vessel full of water is quickly 
 heated from below. But to communicate 
 heat downwards from this hydrostatic 
 law, is tedious and inefiectual. Not Hke 
 a bar of iron, which is heated almost 
 equally soon, whether its upper or lower 
 end be thrust into the fire. So diEcult is 
 it to heat fluids from above, that Count 
 Rumford inferred, that they were absolute 
 non-conductors of heat. A mass of water 
 heated from below, has the temperatures 
 
 • Ree’i Cyclopedia, Art. 
 
EFFECTS OF HEAT. 
 
 137 
 
 of the successive strata, reckoning upwards 
 in an accelerating progression, and the 
 centre of the vessel partakes more of the 
 temperature of the bottom, than of the top. 
 The progression is very nearly arithmetical, 
 and Mr. Leslie informs me, that he found 
 it about one degree, for every 10 inches in 
 depth. Thus, when at 212° at the surface, 
 it will be 213°; at 10 inches below, 114°; 
 at 20 inches, &c. 
 
 104. “ If a vessel containing water be 
 placed over a steady fire, the water will 
 grow continually hotter, till it reaches the 
 limit of boiling, after which the regular 
 accessions of heat, are wholly spent in 
 converting it into steam. The water, 
 therefore, remains at the same-pitch of 
 temperature, however fiercely it boils. 
 The only difierence is, that with a strong 
 fire it sooner comes to boil, and more 
 quickly boils away. Hence the reason 
 why a vessel full of water, and plunged 
 into the centre of a larger one, which is 
 likewise filled with that fluid, barely 
 acquires the boiling heat, but will never 
 actually boil. 
 
 S 
 
138 EFFECTS OF HEAT. 
 
 105. “ Hence the boiling beat of a deep 
 cauldron, is always rather greater than that 
 of a shallow pan. This excess, we might 
 estimate at nearly one degree of Fahrenheit, 
 for each foot of depth. The heat of ebul¬ 
 lition must also rise somewhat higher, if 
 the steam be not allowed to escape as fast 
 as it is generated; for which reason, there 
 may be a slight difference of energy between 
 rapid and slow boiling. 
 
 106. “ But the position of the boiling 
 point, is likewise modified by the influence 
 of chemical attraction. Thus, sugar, com¬ 
 mon salt, and other saline substances, have 
 all of them a tendency to fix water, and 
 retard the crisis of its conversion into 
 elastic vapour. Strong brine will not boil 
 until it is heated up several degrees above 
 the ordinary limit. Hence, a vessel con¬ 
 taining fresh water, and immersed in 
 another which is filled with brine, will 
 gently boil while the surrounding fluid 
 only simmers. On the other hand, the 
 addition of alcohol, renders water more 
 volatile. In the distilation of spirits, the 
 
EFFECTS OF HEAT. 139 
 
 fermented liquor in the copper, boils 
 always at a lower temperature, or at some 
 intermediate point between the ebullition 
 of water, and that of alcohol. The spirit¬ 
 uous fumes which rise, carry along with 
 them a portion of evapourated water 
 
 Of Steam or Vapour. 
 
 lOY. Elastic fluids, which by’ cold or 
 pressure are reduced wholly to a liquid 
 state, are denominated vapour or steam. 
 Such are the elastic fluids arising from 
 water, alcohol, ether, mercury, &c. It is 
 proper to distinguish' these elastic fluids 
 from those which have not yet been re¬ 
 duced into a liquid state, by the agency 
 of cold and pressure, which are commonly 
 denominated gases. 
 
 108. It is stated in Article 44, that bodies 
 by changing their state, also change their 
 specific heat; and hence, when a fluid is 
 converted into vapour,^ it absorbs a gi'eat 
 quantity of heat. 'Were a great quantity 
 
140 
 
 EFFECTS OF HEAT. 
 
 of heat not necessary to the production of 
 vapour, and the body already heated to 
 that temperature, which it cannot pass the 
 smallest possible degree, without being 
 converted into steam; the consequence 
 would be, an explosion of the whole water 
 like gun-powder. But this great quantity 
 of heat enters gradually into the vapour 
 while it is forming, -vnthout making it 
 perceptibly hotter to the thermometer, for 
 it is found to be exactly of the same tem¬ 
 perature, as the boiling water from which 
 it arose. The water must be raised to a 
 certain temperature, because of that tem- 
 peratmre only, it is disposed to absorb 
 heat, and it is not instantly exploded, 
 because in that instant, there cannot be 
 had through the whole mass, a sufficient 
 supply of heat. 
 
 On the other hand, it is found, that 
 when the vapour of water is condensed 
 into a liquid, the same great quantity of 
 heat is evolved, and the water into which 
 it is xdianged, does not become colder to 
 the thermometer by the loss of this great 
 
EFFECTS OF HEAT. 
 
 141 
 
 quantity of heat. We are indebted to 
 Dr. Black for this great discovery, wiiich 
 was the origin of his doctrine of latent 
 heat. He brought to maturity his specu¬ 
 lations on this subject, between the years 
 1759 and 1763*. In these inquiries, he 
 was assisted by his pupils, Mr. Watt and 
 Dr. Irvine. Soon after this period, [viz. 
 in 1764,) Mr. Watt made his first great 
 improvement on the steam-engine. 
 
 109. The combination of a certain 
 quantity of heat in steam. Dr. Black estab¬ 
 lished by the following facts. 
 
 The water in a vessel set upon the fire, 
 becomes hotter till it reaches 212°, but 
 afterwards, although heat must be con¬ 
 stantly proceeding from the fire, no increase 
 of temperature takes place', tire heat must 
 therefore combine with that part of the 
 water which flies off in steam. But the 
 temperature of the steam, is only 212°, 
 therefore the heat combined with it, does 
 not increase the temperature. 
 
 • See Preface to Black’s Lectures, p. sxxv. 
 
142 EFFECTS OF HEAT. 
 
 110. “Mr. Watt put three inches of 
 water into a small copper digester, and 
 screwing on the lid, he left the safety 
 valve open. He then set it on a clear fire 
 of coaks, and after it began to boil and 
 produce steam, he allowed it to remain on 
 the fire half an hour, with the valve open. 
 Then taking it off the fire, he found that 
 an inch of water had boiled away. In 
 the next place, he restored that inch of 
 water, screwed on the lid, and set it on the 
 fire; and as soon as it began to boil, he 
 shut the safety valve, and allowed it to 
 remain on the fire half an hour as before. 
 The temperature of the whole, was many 
 degrees above the boiling point. He took 
 it off the fire and set it upon ashes, and 
 opened the valve a very small matter. 
 The'steam rushed out with great violence, 
 making a shrieking noise for about two 
 minutes. When this had ceased, he shut 
 the valve, and allowed all to cool. When 
 he opened it, he found that an inch of 
 water was consmned 
 
 • Slack’s Lectures, vol, i, p, 160. 
 
EFFECTS OF HEAT. 
 
 143 
 
 111. Dr. Black found, in tWs climate, 
 that it requires 6 times the number of 
 minutes to boil off a small quantity of 
 water, than it takes to bring it to boil. 
 
 Hence, 6 times the quantity of heat,? 
 which it requires to bring the water to 
 the boiling point, is combined with the 
 steam, and Mr. Watt found from accurate 
 experiments, an exact coincidence between 
 the heat thus combined with the vapour, 
 and that which emerges from it when 
 condensed or re-converted into water. 
 “ A7id that the heat obtamable from steam, 
 capable of sustaining the ordinary pressure 
 of the atmosphere^ is not less than 900° of 
 Fahrenheits scale^ and that it does not exceed 
 950°*.” j Calculations from experiments 
 made by Lavoisier, on the melting of ice, 
 produce a value somewhat higher, of the 
 heat which Dr. Black called latent of 
 steam, “ f making it 1000°, or perhaps a little 
 more. 
 
 ^ See Black’s Lectures, voL u p. 175. 
 
 t Ibid. p. 175, 
 
144 EFFECTS OF HEAT. 
 
 Hence, the great scalding power of 
 steam. Hence also, the great heat pro¬ 
 duced in the reffigitory of a common still. 
 
 112. Dr. Black observes, “ that it is this 
 •great quantity of heat contained in steam, 
 that makes it so powerful and effectual in 
 the business of cookery*.” He farther 
 says, “ steam is the most effectual carrier 
 of heat that can be conceived, and will 
 deposite it only on such bodies as are 
 colder than boiling water f.” 
 
 113. Whenever a body hotter than 212* 
 comes in contact with boiling water, it 
 raises its temperature and causes it to 
 expand, but when a body colder than 
 212° touches it, the heat quits the vapour, 
 and it becomes water, or is condensed. 
 
 114. Two English gallons of ice-cold 
 water, dashed in small drops through the 
 capacity of a steam cylinder containing 
 three hogsheads, condenses the vapour 
 which fills it 
 
EFFECTS OF HEAT. 
 
 145 
 
 115. Vapour may be condensed by 
 mechanical compression, as well as by 
 cold. 
 
 116. “ Mr. Watt has made a great 
 number of experiments, for ascertaining 
 the bulk into which a cubic inch of water 
 is expanded, when it composes the steam, 
 which at the temperature 212°, sustains 
 the pressure of the atmosphere; some of 
 these were direct, by evaporating a known 
 quantity of water, others were more cir¬ 
 cuitous, deduced from the performance 
 of his engines. The mediurn result, gave 
 about 1800 cubic inches. We may say 
 that a cubic inch of water, forms a cubic 
 foot of such steam 
 
 117. “ As much heat is contained in one 
 gallon of water in the form of steam, as 
 would bring 5i gallons of ice-cold water, 
 to a boiling heat f.” 
 
 118. From the low temperature at which 
 water boils in vacuo, it occurred to Mr. 
 
 ' Biack’s Lectures,, vol. i. p. 17G. f BlacVs Lectures, vot i. p. 185. 
 
 T 
 
146' EFFECTS OF HEAT. 
 
 Watt, Dr. Black and otters, that distilling 
 in vacuo, would be productive of a very 
 great saving of fuel. With this view, Mr. 
 Watt instituted a set of experiments, but 
 says Dr. Black, “ The unexpected result of 
 these experiments is, that there is no 
 advantage to be expected in the manufac¬ 
 ture of ardent spirits, by distilling in vacuo. 
 For we find that the latent heat of the 
 steam, is at least as much increased, as, the 
 sensible heat is diminished *. 
 
 119. In the course of a set of experi¬ 
 ments, made for a practical purpose on 
 steam, of very different degrees of density, 
 a curious fact, I am informed, was observed, 
 viz. that same quantity of voater passed 
 through the same aperture in the form of 
 steam, during the same space of tme, what¬ 
 ever was the degree of density. 
 
 120. “ The elasticity of all the elastic 
 fluids, into which liquids are converted by 
 keat, increases witk tKe tettiperaturG; and 
 the vapour formed when tlie liquid boils 
 
 * Black’s Lectures, vol. i. p. lao. 
 
EFFECTS OF HEAT. 
 
 147 
 
 in the open air, possesses an elasticity just 
 equal to that of air, or capable at a medium 
 of balancing a column of mercury, 30 inches 
 high * ” 
 
 121 “ TABLE of the force of Steam, at diff¬ 
 erent Temperatures from actual experiment, 
 (Betancourt, in Pronfs Archiieciure, Hydrau- 
 
 lique.J 
 
 
 Temperature. 
 
 Force in inches 
 of mercury. 
 
 32° - 
 
 - 0 
 
 42 - 
 
 - .08 
 
 52 - 
 
 - .21 
 
 62 - 
 
 - -.38 
 
 72 - 
 
 - .58 
 
 82 - 
 
 - .87 
 
 92 - 
 
 - 1.26 
 
 102 - 
 
 - 1.74 
 
 112 - 
 
 - 2.37 
 
 122 - 
 
 - 3.16 
 
 132 - 
 
 - 4.16 
 
 142 - 
 
 - 5.43 
 
 152 - 
 
 - 7.00 
 
 Temperature. 
 
 Fcrce in inch 
 of mercury. 
 
 162° - 
 
 ~ 9.07 
 
 1.72 - 
 
 - il.O 
 
 182 - 
 
 - 14.9 
 
 192 - 
 
 - 18.7 
 
 102 - 
 
 - 23.7 
 
 212 - 
 
 - 29.8 
 
 222 - 
 
 - 37.4 
 
 232 - 
 
 - 46.5 
 
 242 - 
 
 - 57.3 
 
 252 - 
 
 - 69.7 
 
 262 - 
 
 - 83.6 
 
 272 - 
 
 - 97.1 
 
 282 - 
 
 - 10.8 
 
 “ In the 5th volume of' Memoirs of the 
 Manchester Society,’ a table of the force of 
 
 vapour, for each degree of Falirenlieit, is 
 
 given by Mr. Dalton; the numbers below 
 
 * Thomson’s Chemistry, vol. i. p. 369. 
 
148 EFFECTS OF HEAT. 
 
 212 degrees, from experiment, and the 
 higher numbers from calculation. Mr. 
 Betancotut, however professes to have 
 obtained all the above results from actual 
 experiment,” 
 
 122. “ TABLE of the Expansion of a given Bulk 
 
 of Air, hetdceen 32° and 212° Fahrenheit.” 
 
 Tem. 
 
 Bulk. 
 
 Tem. 
 
 Belfc. 
 
 Tem. 
 
 Bulk. 
 
 32° 
 
 100000 
 
 59° 
 
 105616 
 
 86° 
 
 111232 
 
 33 
 
 100208 
 
 60 
 
 105824 
 
 87 
 
 111440 
 
 34 
 
 100416 
 
 61 
 
 106032 
 
 88 
 
 111648 
 
 33 
 
 100624 
 
 62 
 
 106240 
 
 89 
 
 111856 
 
 36 
 
 100832 
 
 63 
 
 106448 
 
 90 
 
 112064 
 
 37 
 
 101040 
 
 64 
 
 106656 
 
 91 
 
 112272 
 
 38 
 
 101248 
 
 65 
 
 106864 
 
 92 
 
 112486 
 
 
 101456 
 
 66 
 
 107070 
 
 93 
 
 112688* 
 
 40 
 
 101664 
 
 67 
 
 107280 
 
 94 
 
 112896 
 
 41 
 
 101872 
 
 68 
 
 107488 
 
 95 
 
 113104 
 
 42 
 
 102080 
 
 69 
 
 107696 
 
 96 
 
 113312 
 
 43 
 
 102288 
 
 70 
 
 107904 
 
 97 
 
 113520 
 
 44 
 
 102496 
 
 71 
 
 108112 
 
 98 
 
 113728 
 
 45 
 
 102764 
 
 72 
 
 108320 
 
 
 113936 
 
 46 
 
 102912 
 
 73 
 
 108528 
 
 100 
 
 114144 
 
 
 103120 
 
 74 
 
 108736 
 
 110 
 
 116224 
 
 48 
 
 103328 
 
 75 
 
 108944. 
 
 120 
 
 11'8304 
 
 49 
 
 103536 
 
 76 
 
 109152 
 
 130 
 
 120384 
 
 SO 
 
 103744 
 
 77 
 
 109360 
 
 140 
 
 122464 
 
 51 
 
 103952 
 
 78 
 
 109568 
 
 ISO 
 
 144544 
 
 52 1 
 
 104160 
 
 79 
 
 109776 
 
 160 
 
 126624 
 
 53 
 
 104268 
 
 80 
 
 109984 
 
 170 
 
 128704 
 
 51 
 
 104576 
 
 81 
 
 110192 
 
 180 
 
 130784 
 
 
 104784 
 
 82 
 
 110400 
 
 190 
 
 132S64 
 
 36 
 
 104992 
 
 83 
 
 110608 
 
 200 
 
 134944 
 
 
 105220 
 
 84 
 
 110SI6 
 
 210 
 
 137024 
 
 5S 
 
 105408 
 
 85 
 
 111024 
 
 1212 
 
 137440 
 
EFFECTS OF HEAT. 149 
 
 123. “ TABLE of ihe Expansion of Liquids 
 by Heat” 
 
 124. “ TABLE of ihe Expansion of Water 
 
 by Heat.” 
 
 I Temp. I Expansion 
 
 42.5° 
 
 52.5 
 
 62.5 
 
 12.5 
 
 82.5 
 
 92.5 
 
 100000 
 
 100030 
 
 100106 
 
 100182 
 
 100273 
 
 00471 
 
 102.5 .00624 
 
 
 112.5° 
 
 122.5 
 
 132.5 
 
 142.5 
 
 152.5 
 
 162.5 
 
 172.5 
 
 100777 
 
 101006 
 
 101220 
 
 101495 
 
 101755 
 
 102040 
 
 102260* 
 
 
 iiistr)', Appendix, p. xxx. xxxi. 
 
150 
 
 EFFECTS OF HEAT. 
 
 SECTION VII. 
 
 Of Ignition- 
 
 125. “ By ignition (says Mr. Murray) is 
 meant that illumination or emission of light 
 produced in bodies, by exposing them to a 
 high temperature, and which is not accom¬ 
 panied by any other chemical change in 
 them. It is to be distinguished from 
 combustion, a process in which there is 
 also the emissioa of light and heat. Com¬ 
 bustion is always the result, not of mere 
 increase of temperature in the body which 
 suffers it, but of the chemical action of the 
 air, or of a principle which the air contains. 
 A certain class of substances, therefore, de¬ 
 nominated Combustible, are alone suscepti¬ 
 ble of it, and when the process has ceased, 
 the body remains no longer combustible. 
 Ignition is an effect of the operation of calo¬ 
 ric alone; it is wholly independent of the 
 air, for by immersing completely any body 
 in melted glass, it is rendered luminous; 
 all bodies, at least all solid and .liquid 
 substances, are equally susceptible of it: 
 
EFFECTS OF HEAT. 
 
 151 
 
 and if it has ceased from a reduction of 
 temperature, it may be renewed by the 
 tempei'ature being again raised,” 
 
 126. “ The point of temperature, at 
 which the first stage of ignition takes 
 place, or at which, in common language, 
 bodies arrive at a red heat, appears to be 
 the same in all. Mr. Wedgwood gilded 
 lines, running across a piece of earthen 
 ware, and luted it to the end of a tube, 
 which was placed in a heated crucible; 
 the eye being applied to the other extrem¬ 
 ity of the tube, no difference of time could 
 be perceived in either the gold or the 
 earthen ware, beginning to shine. No 
 two substances can be more dissimilar; 
 and it may be inferred that all bodies 
 become red-hot at the same temperature. 
 As . this can be judged of, only by the 
 illumination, it must, of course, appear 
 various according to circumstances. In a 
 body, therefore, which in the dark appears 
 at a low red heat, the illumination will 
 not be visible in day-light. Sir Isaac New¬ 
 ton, by observing the celerity with which 
 
152 EFFECTS OF HEAT. 
 
 a body cools, and calculating on tbe prin¬ 
 ciple wbich. has been already pointed out, 
 (p. 161), concluded, that ignition visible 
 in the dark, corresponds with 635° of 
 Fahrenheit’s scale, full red heat with 752°; 
 and ignition visible in day-light, with 
 above 1000°. Dr. Irvine having found 
 that quicksilver boils at 672°, and having 
 observed, that boiling mercury did not 
 appear at aU luminous in the dark, it ne¬ 
 cessarily followed, that the point of igni¬ 
 tion must be higher than Newton had 
 supposed it to be. He had farther found, 
 that when equal hulks of hon and water 
 at different temperatures are mixed to¬ 
 gether, the resulting temperature is nearly 
 the mean^ and he applied this method to 
 determine the point of ignition; the result 
 is hot precisely known; but the heat of a 
 common cod fire, he found to be 790° or 
 796°*. Mr. Wedgwood by the expan¬ 
 sion of the piece of silver, measured by a 
 gage of baked clay, by which he endeav¬ 
 oured to connect his thermometer with 
 
 • Chemical Essays, p. S3. 
 
EFFECTS OF HEAT. 
 
 133 
 
 Fahrenheit’s, as has been already ex¬ 
 plained, fixed the point of ignition visible 
 in the dark, at —1 of his scale, which cor¬ 
 responds with 947° of Fahrenheit; and 
 ignition in day-light, he placed at the 
 commencement of his scale, or 1077°. 
 This differs from the preceding results; 
 and as it is probable that the silver would 
 sufier an increasing expansion, this might 
 cause the temperature to. appear higher 
 than it actually was, and hence, have 
 given the point of ignition too high. It 
 is probably not far from 800° of Fahren¬ 
 heit. . 
 
 127. “ By raising the temperature, the 
 illumination becomes brighter, and the 
 red heat acquires a mixture of yellow 
 rays. At length, by increasing the heat, 
 we have the due proportion of coloured 
 rays, which forms perfectly white light,. 
 This is the highest state of ignition, or 
 any farther rise of temperature produces 
 no apparent change. 
 
 U 
 
154 
 
 EFFECTS OF HEAT. 
 
 128. “ Ignition continues undimin- 
 ishedj.as long as the temperature is kept 
 up, unless the heat be such as to volatilise 
 of alter the constitution of the ignited 
 body. 
 
 129. “ The aeriform fluids are not 
 brought into a state of illumination by 
 heat. This was observed by Dr. Fordyce, 
 in the example of the vapour, at the end 
 of the flame of a blow-pipe, which though 
 itself not visibly luminous at its extrem¬ 
 ity, will, if applied to glass, raise it to a 
 white heat*. The fact was afterwards 
 also established by Mr. Wedgwood. Air 
 was forced to pass through an earthen 
 tube, in a state of ignition, and was con¬ 
 ducted into a globular vessel, from which, 
 by an opening in the top, it was allowed 
 to escape j while by another opening in the 
 side, closed by a piece of glass, the eye 
 could be directed into the inside of the 
 globe. On looking into it, the air which 
 had passed through the ignited tube was 
 
 • PHL Trans, vol. Uvi. p. 504, 
 
EFFECTS OF HEAT. 
 
 155 
 
 not luminous; but if a solid body, as a 
 piece of gold, was suspended in it, this 
 became luminous This is probably 
 owing to the tenuity of aeriform fluids, 
 whence they present too few points in a 
 given space, to project a quantity of light 
 sufficient to excite vision. 
 
 130. “ The phenomena of ignition are 
 produced, not only by the application of 
 heat, but likewise by friction and attri¬ 
 tion. When a piece of steel is struck 
 against a flint, small particles of the 
 metal are detached, which are at a red 
 heat. Or if various hard minerals be 
 made to act strongly against each other, 
 they give out light. By applying, for 
 example, quartz or agate to the circum¬ 
 ference’of awheel of fine grit, revolving 
 at a moderate rate; Mr. Wedgwood ob¬ 
 served, that the substance applied became 
 brightly red even in day-light, at the 
 touching part; if the wheel revolved at a 
 quicker rate, the part in contact emitted a 
 
156 
 
 EFFECTS OF HEAT. 
 
 pure white light; and in botli cases, glow¬ 
 ing sparks were continually emitted, some 
 of which were not extinguished before 
 they had passed twelve or fourteen inches 
 through the air. They exploded gun¬ 
 powder and inflammable air; and burnt 
 the skin, a sufficient proof that they were 
 not merely luminous or phosphorescent, 
 but ignited, or at a red heat. In the same 
 mode, glass and porcelain were raised to a 
 red heat. These appearances from attri¬ 
 tion, are probably to be ascribed to the 
 heat which is excited, rising sufficiently 
 high to extricate their light, as the same 
 bodies become luminous when directly 
 heated, and as the same appearances are 
 not produced in substances which are 
 soft, these not having their temperature 
 raised by attrition 
 
 • Murray’s Chemistry, voL i. p. 253—2S7. Phih Trans, for 
 1792, p. 39. 
 
Description of Plate 
 
 131. Fig. 1, is a comparative view of Fahreaheit’s scale, 
 and Mr. Dalton’s new divisions of the scale of the mercurial 
 thermometer. The interval from freezing to boiling water, 
 is 180° on both scales, and the extremes are numbered 32° 
 and 212° respectively. “ There are no other points of tem¬ 
 perature in which the two scales can agree 
 
 Fig. 2, represents Reaumeur’s scale, as also that of,the 
 centigrade, (Art. 10, 11). 
 
 I^g. 3, shows the scale proposed by Mr. Murray, 
 (Art. 12). 
 
 Fig. 4, represents the connection of the mercurial ther¬ 
 mometer, with that of Mr. Wedgwood, (Art. 26). 
 
 Fig. S, “ is the logarithmic curve, the ordinates of which, 
 are erected at ecpral intervals, and diminish progressively by 
 the ratio |. The intervals of the absciss or base of the 
 curve, represent equal intervals of temperature, (25° for 
 steam or aqueous vapour, and 34° for ethereal vapour,) the 
 ordinates represent inches of mercury, the weight of which 
 is equal to the force of steam at the temperature. Thus the 
 force of steam at 212°, and of ethereal vapour at 110°, new 
 scale, is equal to 30 inches of mercury; at 187° the force of 
 steam is half as much, or 15 inches, and at 76°, that of 
 ethereal vapour is also 15 inches, &c. (Art. 24.). 
 
 Fig. 6, represents Mr. LesKe’s differential thermometer, 
 
 (Art. 80). 
 
 •Dalton’s Chem. Phil. p. 217. tDalton’sChem. Phil. p. 21s. 
 
 JENJ) OF PART FIRST. 
 
^art ^ecottH. 
 
 HEATING 
 
 MILLS, DWELLING HOUSES, AND 
 FUBLIC BUILDINGS, 
 
 By steam. 
 
 SECTION I. 
 
 132. It may be proper, in general, to 
 mention, that the steam is usually gener¬ 
 ated in a boiler similar to those employed 
 for steam-engines, and having similar 
 apparatus for , supplying it with water. 
 The boiler is placed in any convenient 
 
160 
 
 EFFECTS OF HEAT. 
 
 situation, in or near the building to be 
 warmed; from it the steam is conveyed in 
 pipes, through the various rooms where 
 heat is required. 
 
 Of the p’opoi'iionafe size of Boilers. 
 
 133. The proportionate size of boilers 
 is a point of considerable practical impof- 
 .tance. It has been ascertained, that one 
 cubic foot of boiler will heat about two 
 thousand cubic feet of space, in a cotton 
 
 mill*; (See Notes A. and B.) and if we 
 reckon twenty-jive f cubic feet for every 
 horse’s fowerX in a steam-engme boiler; of 
 course, such a boUer of a steam-engine, 
 wotdd be capable of warming fifty thou¬ 
 sand cubic feet of space for every horse s 
 power of the engine. 
 
 * In cotton mills the temperature xs in general from 70 to 80 degrees 
 ef Fahrenheit. 
 
 1 am aware that the quantity of steam, which a boiler will pro¬ 
 duce, depends much more on the surface applied to the fire, than on its 
 cubical Contents: but I here allude to boilers of the form at present 
 most generally used in steam-engines. Twenty-five cubic feet, how¬ 
 ever, is an ample allowance. See Art. 64. 
 
 I Respecting the resistance to which a horse’s power Is estimated by 
 mechanics, as being equal. See my “ Essay on the Teeth of Wheels.” 
 
EFFECTS OF HEAT. 161 
 
 134. A separate boiler ought, however, 
 to be considerably larger than the extra 
 size allowed on a boiler, used for the joint 
 purpose of a steam-engine and warming a 
 mill; to avoid the inequality of heat inci¬ 
 dent to a boiler working to the full extent 
 of its capacity. 
 
 135. Having ascertained the size of the 
 boiler, the fuel may be easily estimated by 
 the following rule, which I believe Messrs. 
 Boulton and Watt adopt with respect to 
 their steam-engines: That is, about 14 lbs. 
 per hour of good Newcastle coal, for each horse s 
 power. It may be proper, however, in 
 general, to make a large additional allow¬ 
 ance for defects in furnaces, and inattention 
 in the attendants. See Art. 59—70. 
 
 X 
 
162 
 
 EFFECTS OF HEAT. 
 
 SECTION II. 
 
 Of the propoi-tion of Steam-pipe required to xvqrm 
 a given -ipace. 
 
 136. In cotton mills, it has been ascer¬ 
 tained, that, in most cases, one siiperjiciat 
 foot of exterior surface of steam-pipe^ will warm 
 two hundred cubic feet of space. A larger 
 allowance, however, of steam-pipe is usually 
 
 given. Mr. H. Houldsworth, in the mill 
 at Anderston, has about one hundred and 
 seventy-nine cubic feet of space, to one su¬ 
 perficial foot of external surface of steam- 
 pipe. Messrs. Kennedy and Watt at 
 Johnston, allow about one hundred and 
 sixty-eight feet. At Catrine, about two hun¬ 
 dred. But the temperature in those mills, 
 is much greater than is required for common 
 purposes, being from 70 to 85 degrees of 
 Fahrenheit. (See Note B.) Mr. Macnaught 
 has lately warmed a small chapel at Port- 
 Glasgow, to a comfortable temperature, by 
 onefoot surface of steam-pipe to four hundred 
 cubic feet of space. 
 
EFFECTS OF HEAT. 
 
 163 
 
 137. In the above examples, die steam 
 used, is about the strength usually employed 
 in Messrs. Boulton and Watt’s engines *. 
 Stronger steam would, no doubt, emit 
 more heat from a given surface of steam- 
 pipe, but it would be difficult in that case, 
 to keep the joints steam-tight. 
 
 138. The nature of the building ought 
 first to be considered, whether much exposed 
 to cold winds, whether it be closely finished, 
 whether there be much wall, in proportion 
 to its capacity, whether the temperature 
 required, be moderate or high. These 
 circumstances being taken into considera¬ 
 tion, a judgement may be formed of the 
 proportion of steam-pipes, from what has 
 been ascertained to be sufficient in existing 
 cases. (See Note B.) 
 
 ■ • That is, the safety-valve on the boiler to be loaded to about 2^ lib. 
 to the square inch. 
 
164 EFFECTS OF HEAT. 
 
 SECTION III. 
 
 Of the Substance, and Surface of the Steam-pipe. 
 
 139, In order to save espence, pipes of 
 tin-plate have been tried, in preference to 
 cast-iron. It was supposed too, that from 
 its thinness, it would emit the heat more 
 rapidly than cast-iron. Upon the same 
 idea, thin copper pipes* were also tried 
 Contrary to expectation, however, it was 
 soon found, that the same surface of cast- 
 iron gave out much more heat, than either 
 the tin-plate or copper. 
 
 140. Mr. H. Houldsworth made some 
 experiments to ascertain the difference 
 between tin-plate and cast-iron, with respect 
 to their effects in emitting heat; and found, 
 by measuring the quantity of steam con¬ 
 densed in equal lengths of pipe, or, in other 
 
 ♦Copper tnbes when heated, emit a disagreeable smell, which it ii 
 probable is as unwholesome as it is unpleasant. Lord Landsdown at 
 great expence, applied them under the floor of his Library with a view 
 to having it wanned by steam, but whether from this cause or from 
 the arrangement being improper, I know not, but the plan wag aban¬ 
 doned. 
 
EFFECTS OF HEAT. 
 
 165 
 
 words, by measuring the water of conden¬ 
 sation, (Art. 45,) that, taking the effect of 
 tin-plate in emitting heat as one^ the effect 
 of cast-iron was equal to two and a half*. 
 
 141. One of the apartments of the 
 Adelphi cotton-mill, Glasgow, which had 
 steam-pipes made of tin-plate, was not 
 found so warm as was required. When 
 
 this occurred, my attention was directed 
 to some of Professor Leslie’s experiments 
 on heat, this induced me to try the effect 
 of painting them black; the increase of 
 heat, from painting, was great beyond ex¬ 
 pectation. 
 
 142. This trial led me to suspect that the 
 greater effect of cast-iron arose, not from 
 the nature of the substance, but from the 
 
 ■ * These experiments were made on tin-plate tubes. 5^ mcliea 
 'external diameter, condensed 6 lbs. of water in the time that those o£’ 
 #ast-iron 7^ external diameter, and of equal length condensed 22 lbs. 
 
 Juchei Lib. Lickct Lib. 
 
 as 5\i : 6 ; : 7^. « 8. 2. the quantity proportionate to the 
 
 diameter of the pipe, iiue and a half which amounts to 20f lib, 
 hut the real quantity condensed we saw w'as 22 Hb. It is proper to 
 observe, that the tin-plate tubes were considerably tarnished by being 
 about 2 years in use, (Art, 90). 
 
166 EFFECTS OF HEAT. 
 
 colour and nature of the surface. I therefore 
 liad some experiments made to ascertain 
 tius fact"^. The results were sufficient for 
 my purpose at the time; but it were to be 
 wished, that' the subject might be examined 
 by others with still greater accuracy. It 
 appeared, that when equally dark in colour, 
 and when the, surface was equally rough, 
 tin-plate emitted heat as rapidly as cast- 
 iron 
 
 143. Cast-iron, however, has been found 
 much more durable, and convenient, in 
 its application, than other metals, which 
 have been tried. And it appears, when 
 durability is required, that it is the only 
 substance which seems properly applicable 
 to the purpose. Indeed it has been adopt¬ 
 ed in most of the late cases of warming 
 
 *ThKe experiments were made somewhat in the manner o£ those 
 of Professor Leslie. 
 
 ' There was a canister having fonr egnal sides, three of which were 
 of tin-piate, and one of cast-iron. This canister was filled with hot 
 .water, and an air themometer indicated the temperature. 
 
 ,f Whether this effect proceeded from the joint operation of colour 
 and roughness of surface, or from roughness alone, my experiments did 
 not ascertain. Mr. Houldsworth tried cast-iron pipes painted various 
 colours, hut found no difference of heat. (Art 90). 
 
EFFECTS OF HEAT. 
 
 167 
 
 by' steam Some, nevertbeless, still pre¬ 
 fer tin-plate pipes, as being cheaper, more 
 speedily erected, and, when painted, as 
 effective in emitting heat. 
 
 144. With regard to the thickness of 
 the pipes, I do not suppose that this is to 
 be limited but by expence; for.a thick pipe, 
 
 acting e^s <), reservoir of heat, preserves a 
 
 more uniform temperature than a thin one. 
 It is usual, however, in order to save expence, 
 to make them as, thin as they can be con¬ 
 veniently cast, which may be from a half 
 to three-fourths of an inch. Professor 
 beslie obligingly suggested to me, that 
 whenever the steam tubes come in contact 
 with the walls of a building, in order tq 
 save the heat, a piece of tin-plate should 
 be, interposed, (Art. 90.) 
 
 ^ Lead is a very improper material for conveying steam, it soon cracks, 
 and becomes no longer steam-tight. When steam-pipes are made of 
 
EFFECTS OF HEAT. 
 
 igs 
 
 SECTION IV. 
 
 Genered Ohservaiions respecting the Direction and 
 Ai-rangement of the Pipes. 
 
 145. Tn the arrangement of steam-pipes, 
 one of the greatest difficulties which occurs, 
 proceeds from the expansion of the metal. 
 -^Whea the pipes are single, this is easily 
 overcome; but where pipes are connected 
 at various angles, the principal difficulty is, 
 at the same time, to preserve the joints, 
 and give liberty for expansion. 
 
 146. To give some idea of the effect of 
 the heat of steam, in producing expansion, 
 I may mention, that a copper steam-pipe 
 160 feet long, was two inches longer when 
 filled with steam, than when cool; and 
 that in practice, the expansion of steam-pipes of 
 cast-iron may be taken at about one-tenth of an. 
 inch, in ten feet of length. 
 
 147. “ Brass expands about one hundred 
 thousandth of its length, for each degree 
 of Fahrenheit; copper and gold a little less; 
 
HEATING BY STEA:m. 169 
 
 silver somewhat more; iron and steel, about 
 two-thirds as much; tin, one-third more; 
 and lead and zinc about half as much 
 more^^.” (See Art. 28, 37.) 
 
 148. Count Rumford, in warming the 
 Lecture-Room of the Royal Institution, by 
 Steam, used drums of thin copper at the 
 terminations of the pipes; the heads of 
 these drums were about three feet in diam¬ 
 eter, and yielded" to the expansion of the 
 pipes. This plan, however, in most sit¬ 
 uations, would require too much space, 
 and be attended with too much expence. 
 
 149. When a straight pipe, filled with 
 steam, stands in a vertical position, it is 
 equally heated all round, and expanding 
 equally, continues to be straight, but when 
 it lies in a horizontal direction, the upper 
 side becbines the hottest, and expanding 
 more than the lower, bends the pipe, which 
 in some cases endangers the joints. Mr. 
 Dalton, in a letter of the 14th June, 1808, 
 
 •Young’s Nat. PhiL vol. i. p. 643. 
 
 Y 
 
170 HEATING BY STEAM. 
 
 with wHcli he favoured me, respecting my 
 pamphlet on warming buildings by steam, 
 says, 1 do not feel convinced of the ad¬ 
 vantages of vertical pipes, they must diffuse 
 less heat, having a hot current of air sweep¬ 
 ing them. Could not the bending of the 
 horizontal pipes, by unequal temperature, 
 be prevented by soldering a small dn-plate 
 to the upper surface of the pipe. This 
 would take the excess of heat from the 
 upper surface and dissipate it.” 
 
 Since publishing the pamphlet above 
 alluded to, experience and reflection have 
 convinced me of the justice of Mr. Dalton’s 
 observations, and I find it is only in case 
 of joints made with flanches of great dia¬ 
 meter, that there is any danger of their 
 
 brea ki ng in a horizontal position from 
 unequal expansion *. When air is heated, 
 becoming more rare,; it has a tendency to 
 
 »la a mill which Mr. Hoaldsworth has heated hy very thin cast-iron 
 steam pipes, he found that several of those which were vertical gave 
 w^ .,in the. thimh le joints, while all those which were horizontal 
 r etrain ed good. The reason of this difference probably is, that the 
 horizontal pipes are more gradually heated^ hy the water of conden¬ 
 sation going before the steam. 
 
HEATING HY STEAM. _ 171 
 
 ascend, horizontal pipes should, therefore, 
 when practicable be placed near the floor, ' 
 (Art. 89). 
 
 150. In arranging steam-pipes, two 
 points require considerable attention: First, 
 conveniently to expel the air; and, secondly, 
 to take o£F the water resulting from the 
 condensation of fhe steam; which, to avoid 
 circumlocution, we shall call the water of 
 condensation. 
 
 In regard to the first point, the steain, in 
 entering the pipes, may be considered as a 
 kind of a piston, driving the air before it: 
 for the steam and air mix very imperfectly 
 in the pipes, and there appears almost a 
 
 distinct line between their surfaces. This 
 
 principle should tlierefore be kept in view, 
 in fixing upon the place of file opening for 
 allowing the dr to escape, ' while the pipes 
 are filling. One or more passages is like¬ 
 wise necessary, after the pipes are filled, 
 in order to allovv a small portion of steam 
 constantly to escape, to keep up , the heat 
 in the pipes. For if this be not done, dr 
 will accumulate, and occupy the place of 
 the steam. _ 
 
172, HEATING BY STEAM, 
 
 151. With regard to the second -pomt, 
 when it can conveniently be done, it is 
 better to make the water of condensation^ to 
 run in the same direction with the steam. 
 Indeed, in a horizontal pipe, the steam will 
 drive the water before it, and will do so 
 when the internal diameter does not exceed 
 %. inches; even if the pipe should have a 
 considerable acclivity. Great care, how¬ 
 ever, should be taken, to prevent the water 
 from lodging in any part of the pipes. 
 From want of due attention to this circum¬ 
 stance, accidents have not unfrequently 
 happened. The water remaining in the 
 pipes after they become pool, keeps one 
 part of diem cold. The consequence is, 
 that next time the steam is let into the 
 
 pipes, the regular’expansion is prevented, 
 
 some part of the pipe cracks, and a violent 
 explosion takes place, racking the joints, 
 to a considerable distance in every direct 
 tion, froni the place of explosion, 
 
 152. In most cases, it is attended with 
 least labour and expence, to place the pipes 
 in the horizontal direction. 
 
HEATING BY STEAM. 
 
 vm 
 
 SECTION V. 
 
 Of the Methods qf Connecting the Steam-Pipes. 
 
 Method 1. Figure 1. . 
 
 153. Represents the ■ method of con¬ 
 necting pipes by means oi flancJies, A 
 and B are the pipes, the projecting parts 
 CD, are called the jianches. 
 
 The junctures are secured by interposing 
 rope-yarns, or some other pliant substance, 
 and iron-cement, and then screwing up 
 the whole by means of the screw-bolts 
 EE, &c. In all cases where bolts are used 
 in steam-pipes, they ought to be carefully 
 lapped with rope-yarn. 
 
 Ohsei'vations. 
 
 When the pipes are horizontal, from in¬ 
 equality of expansion, the fanches are liable 
 to be brojcen, or at least to leak at the bole 
 holes.. For vertical pipes, they may often 
 be applied with advantage. This seems 
 to have been one of the oldest methods in 
 use, for the purpose of connecting cast-iron 
 pipes, (See Belidores Arch. Hydraulique). 
 
HEATING BY STEAM. 
 
 .174 
 
 N. B. All the observations which are 
 here made on the modes of connecting 
 pipes, relate to tlie conveying of steam only. 
 
 Method 2. Figure % 
 
 . 154. Represents a spigot and facet joint. 
 The juncture is secured by iron-cement, 
 to the space between the spigot AB, 
 and the facet CD. 
 
 Oiservations. 
 
 Spigot and facet joints do very well in 
 most cases, but there have been instances 
 of facets bursting from the greater expan¬ 
 sion of the spigots. The risk of this 
 accident is increased, by increasing the 
 space for the cement. 
 
 Method 3. Figure 3. 
 
 155. This figme represents a thimble 
 joint, which is secured in a similar manner 
 with method 2. 
 
 Obsei'iiations. 
 
 This is a very convenient, mode of join¬ 
 ing steam-tubes. If a thimble burst, it is 
 
HEATING BY STEAM. 175 
 
 : easily renewed, and any one pipe may be 
 "moved without disturbing the rest, which 
 cannot be done by method 2. Thimbles 
 are often used also to repair spigot and 
 facet pipes; when the facets break, some¬ 
 times it is convenient to make the thimbles 
 in two , parts, as represented by No, 4. 
 Fig. 3. It |)ccurs to me, that it would be 
 an improvement to make the thimbles of 
 plate-iron, leaving but a small space for 
 the cement. On this plan, the expansion 
 would be more equal, and the risk of, the 
 joint being injured, of course, much 
 lessened. 
 
 Method 4. Figure 4. 
 
 156. Represents a mode of connecting 
 spigot and facet pipes, where they are, to 
 have a turn or angle. 
 
 Obsenations. 
 
 This method is simple and convenient, 
 when the place where the turn is required 
 is previously known, and the pipes cast 
 accordingly. 
 
176 HEATING BY STEAM. 
 
 Method 5. Figure 5. 
 
 157. Represents what is called the 
 saddle joint, used for taking off a branch 
 'ilie branch has a piece AB formed on 
 its end, which fits round one-half of the 
 outside of the pipe from which it is to 
 spring. CD is called the saddle which 
 fits rcnind the other half of the pipe. 
 Two screvsred hoops FG FG, embrace the 
 saddle, and'the part AB, and cement 
 being interposed, they serve to secure the 
 whole. 
 
 Obsenations. 
 
 By this method a branch may be formed 
 on any part of a pipe, by cutting a hole 
 there, and applying the joint to that place. 
 This easy method of applying a branch is 
 often of great use in practice, and the hoops 
 make it very secure, without the disadvan¬ 
 tage of bolt-holes in the cast-iron. 
 
 158. Where there is much risk of the 
 inequality of expansion, the joints at certain 
 places, should be secured by a soft stuffing 
 of hemp or cotton, and tallow; but in most 
 
HEATING BY STEAM. 
 
 177 
 
 Gases, the joints may be made with iron 
 cement *. Lead has been tried for rniaking 
 the joints, instead of iron cement, though 
 easy of repair, the lead soon gets loose by 
 alternate expansion and contraction. 
 
 159. AtButterly Iron-Works,Derbyshire, 
 
 there is a very good plan of a joint, which 
 has been in use about ,7 years, and during 
 the whole of that period, .it has continued 
 tight and required no repair. It operates 
 for the expansion of a pipe conveying steam 
 about 40 yards, which makesit yield back¬ 
 ward and forward about | of an inch. 
 The two adjoining ends of the pipes A and 
 B, are turned true on the outside, andi have a 
 thimble CDEF, with tin interposed between 
 it and the pipe which being less liable to 
 expansion than lead, has continued durable, 
 and still fits well to the turned parts of the 
 pipe, which work in it like a piston in a 
 cylinder, (See Fig. 6). 
 
 * This cement is composed of dO lbs. iron borings, I do. salamoniac, 
 ^ do, sulphur, well mixed together, and beaten like putty. 
 
 Much sulphur is hurtful, rendering the composition brittle. When, 
 therefore, a considerable time can be allowed for the cement to settle in 
 the joints, before the steam-is applied, a smaller proportion of sulphur 
 than the above, may with advantage be adopted. 
 
 Z 
 
178 
 
 HEATING BY STEAM. 
 
 Method 6. Figure^ 7. 
 
 160. Represents tke method of making, 
 joints, on vertical pipes, when they are used 
 as pillars, for supporting floors. The ends 
 are turned to fit each othetj and iron cement 
 is interposed. The weight is then sufficient 
 to secure the joint. 
 
 Obseroation. 
 
 No. 2. is only used when there is not 
 room for the projecting part on the outside 
 as in No. 1. which is preferable when 
 circumstmices will permit. 
 
 161. Before putting up any of the steam- 
 pipes, they should be proved to be solid, by 
 the usual process of forcing water into them. 
 
HEATING BY STEAM. 179 
 SECTION VI. 
 
 Descriftim of Boiler for generating Steam^xmth 
 Apparatmfor supplying it with Water, regulat¬ 
 ing the Damper, 8^c. 
 
 162. ABCD Eig. 8. represents the boiler 
 which is kept in a state of ebullition, by 
 means of a furnace and fluesi as represented, 
 in the figure, but I shall not at present enter 
 upon the subject of what is called hanging 
 of boilers. 
 
 Apparatus for supplying Water. 
 
 163. E the ffoat which is usually made 
 of stone, but which has a balance-weight, 
 F, so as to make it act as if it were, specif¬ 
 ically lighter than water. The float E 
 swims on the surface of the water in the 
 boiler, and by means of the wire EG is 
 connected with the lever GH, from which 
 by another wire IK, there is a communi¬ 
 cation widi the valve K. The valve K is 
 situated in the bottom of a small cistern, 
 which is ■ constantly supplied with water 
 by a pump, or otherwise. 
 
180 
 
 HEATING BY STEAM. 
 
 When, there is a sufficiency of water in 
 the hoUer, the valve K remains shut. But 
 suppose the water in the boiler to fall too 
 low, we shall see what takes place. The 
 float E sinking along with the water, by 
 means of the intermediate parts already 
 described, opens the valve K, and allows 
 the water to get through the valve, and 
 down the pipe KLMN into the boiler, until 
 it again raise the surface of the water, and 
 along with it the float E, which, of course, 
 again shuts the valve K, and thus prevents 
 the further admission of water, until it 
 be again required. 
 
 Apparattis for Eegulating the Damper. 
 
 164. Connected with the pipe EiLMN is 
 another, but smaller pipe, MNOP, which 
 reaches, usually, within about 12 inches of 
 the bottom of the boiler. 
 
 • In the pipe KLMNO there is a hollow 
 float-vessel O, which is suspended by a 
 chain -OR from the pulley S. The vessel 
 Q has liberty to rise and fall freely in the 
 pipe, which liberty also allows the water 
 
HEATING BY STEAM. 181 
 
 from the feeding-valve K, to escape past 
 its sides, and so into the boiler. 
 
 From another pulley T, the damper W 
 is suspended by another chain TW. 
 
 While the fire is not too violent, the float- 
 vessel Q remains at the bottom of the 
 pipe KLMN, but suppose the fire to become 
 too strong, then the steam pressing on the 
 surface of the water in the boiler, forces 
 part of it up the pipe MNOP, which raises 
 the vessel Q, and by means of the inter¬ 
 mediate parts already described, depresses 
 the damper W, and so by narrowing the 
 passage for the smoke, checks the draught 
 of the furnace, and, of course, damps the ' 
 fire. 
 
 Safety Valves. 
 
 168. In order to prevent accidents, there 
 is a valve a which opens by the elasticity of 
 the steam,. when it exceeds about 2| lbs. 
 upon the square inch, a b is the. pipe 
 which conveys the steam into the building. 
 There are also valves placed on or near the 
 
182 
 
 HEATING BY STEAM. 
 
 boUer,' which open inwards, to prevent 
 accidents from a partial vacuum taking 
 place in the pipes, or boiler. 
 
 Guage-Cocks. 
 
 166. c and d are the guage-cocks.' c 
 communicates with a short pipe, which 
 terminates a little above proper surface 
 of the water. There is another pipe from 
 which terminates a little below that level. 
 Accordingly, as water or as steam forces 
 through either of those cocks, the keeper 
 of the boiler is enabled to judge of the 
 
 height of the water within the boiler. 
 
 Besides the guage-cocks, a glass tube is 
 sometimes used, which shows to the eye, 
 the height of the water in the boiler. The 
 tube is fixed on the outside of the building, 
 and communicates with the boiler, by means 
 of two' pipes, the one tmder the proper 
 level of the smiace oi' the water and 
 the other above it. 
 
 Contrivances to give an Alarm 'when the Water 
 in the Boiler falls too Low. 
 
 167. For this purpose, is sometimes used 
 a pipe of about 24 inches diameter, reach- 
 
HEATING BY STEAM. ISS 
 
 ing from a little way below the proper 
 level of the surface of the water, to about 
 9 feet above the upper part of it; Its upper 
 termination is like an organ pipe. Should 
 the water, therefore, fall too low, the steam 
 rushes through the pipe, and makes a noise 
 which alarms the whole neighbourhood, 
 aiid so may prevent the bottom of the 
 boiler from being burnt out, an accident, 
 by ho means unfrequent. Other means 
 have also been proposed for the same pur¬ 
 pose, such, for instance, as working a stop¬ 
 cock by a float, which, when the water falls 
 
 too low, would allow the steam to blow 
 
 into a Boatswain’s whistle. 
 
184 HEATING-BY STEAM. 
 
 SECTION VIL 
 
 j 168. It may be here observed, in general, 
 witli respect to syphons, 1st, That they 
 should have a pressure of water, of at least 
 9 feet in them, in order to prevent the 
 water from being thrown out of them, 
 which would be the case, with a small 
 pressure, more particularly as the water is 
 Uable to sudden oscillations. 2d, That 
 they should be wide enough to discharge 
 
 the water with ease. 3d, That they should 
 
 be in situations protected from the cold, 
 there having been instances of their being 
 rendered inefiectual from the water freez¬ 
 ing in them. A stop-cock for letting off 
 the air is commonly placed between the 
 steam-pipes and the syphon. Sometimes 
 ' there is a small hole (the size of a pin) 
 made in that part of the stop-cock which 
 is nearest the steam-tubes, in order that 
 there may always be a small quantity of 
 steam escaping to prevent accumulation of 
 air, in any part of the pipes. 
 
185 
 
 HEATING BY STEAM. 
 
 • It frequently occurs, that proper depth 
 cannot conveniently be obtained for a 
 syphon. In that case, a valve to open by 
 a float-ball, has been applied. The valve 
 remains shut, until the water of condensation 
 begins to accumulate, which raises a hol¬ 
 low copper ball attached to the top of the 
 valve, and allows the water to escape. A. 
 syphon is, however, preferable wherever 
 depth for.it can be obtained, being much 
 more simple, and less liable to be put out 
 of order. 
 
 ABC, Fig. 9. represents a syj^hn. The 
 
 water of condensationywYivch. accumulates in 
 the steam-pipe CD, escapes .at A. E is, 
 the stop-cock for allowing the air to escape 
 by the pipe EF. EG is a smaller pipe, 
 which communicates with a very small 
 hole between the stop-cock and the steam- 
 
 I omitted to mention in its proper place, what is called the steam-gaugz. 
 It is a small iron syphon containing some Inches of mercury in its bended 
 part (which is downward). The one leg of the syphon communicates 
 with the ini/cr, or some part of the sUam-jttlns. The other leg commun¬ 
 icates with the atmosphere, and has a small wooden rod in it, which 
 being raised or iJepressed, indicates the different degrees of density of 
 the steam. The steam-gauge is represented by /w. Fig. 8, Plate 2. 
 
186 
 
 HEATING BY STEAM. 
 
 pipe €ID, and allows a very small quantity 
 of steam constantly to escape, as was men¬ 
 tioned in. this Section. 
 
 A syplion of this descr^tion, -with a wide bore, may often with 
 adTantage be nsed as a tafo^ahe to a boiler. It might also be uset^ 
 for aUovring the ’xaitr of eimdauatim to escape, in atuarions where there 
 
HEATING BY STEAM. 187 
 SECTION VIII. 
 
 Description of some Cases, of the Direction and 
 Arrangement of Steam-pipes in Actual Use *. 
 
 169. Having iD.ade some general observ¬ 
 ations, respecting the direction and arrange¬ 
 ment of steam-pipes,—Shaving considered 
 the' various methods of connecting them, 
 and having described the boiler and its 
 apparatus, it may now be proper to notice 
 the direction and arrangement of the pipes, 
 in several cases, in actual use, and,' as we 
 proceed, to make some observations on each 
 of these arrangements. 
 
 Arrangement I. for Seating d Cotton-Mill.' 
 
 170. A horizontal pipe conveys the steam 
 from the boiler into the mill, connected 
 with a vertical pipe reaching nearly to the 
 ceiling of the uppermost room. 
 
 In each floor there is a horizontal pipe, 
 placed about 2 feet below the ceiling, and 
 
 • See also Note B, at the end of this Essay. 
 
188 
 
 HEATING BY STEAM. 
 
 each horizontal pipe has a stop-cock*, 
 where it branches off from the vertical 
 pipe. A syphon for conveying off part of 
 the water of condensation, is placed at the 
 bottom of the vertical pipe. 
 
 Olservations. 
 
 At the Catiine cotton-works, where this 
 ■ arrangement is adopted, the pipes have 
 lieir declivity towards the boiler, so that 
 the water of condensation, runs in an op¬ 
 posite direction to the passage of the Steam. 
 A great proportion of it, finds its way 
 back to the feeding apparatus, by a small 
 pipe; the rest of it, is carried off by the 
 syphon. 
 
 At the further end of each horizontal 
 pipe, there is a small safety-valve opening 
 inwards, to prevent accidents from a vacuum 
 taking place within the pipes. That valve 
 also serves to allow the air to escape, while 
 the pipes are filling with steam. No prac- 
 
 * These stop-co<is at the Catrine works, are common inch-and-hatf 
 brass cocks. 
 
HEATING BY STEAM. 
 
 189 
 
 tical disadvantage is experienced, I am in¬ 
 formed, from all the steam which escapes 
 on that occasion, 
 
 lYl. With horizontal pipes, it Is very 
 common to have a smaller pipe, with a 
 stop-cock from each, going through the 
 wall, to allow the air to escape; but from 
 what has been expei'ienced at Catrine, this 
 precaution does not seem' to be absolutely 
 necessary, nor yet (as is also common) to 
 take oflP the water of condensation from 
 tho further ends of the pipes, m which case 
 the pipes incline in that direction. 
 
 173. ■ I, however, think although less 
 simple, it is a more perfect arrangement to 
 take off the water of condensation from 
 the further end of each horizontal pipe, 
 more particularly when such pipes'are of 
 great length. The water of condensation 
 going before the steam, serves to warm 
 the lower part of the pipe, and make the 
 expansion of the upper and under parts of 
 it more equal, when the steam comes for¬ 
 ward. At Catrine, the tin-plate pipes, have 
 
190 HEATING BY STEAM. 
 
 been in use several years, and proprietors 
 think them sufficiently durable. It is not, 
 however, the general opinion of those who 
 have tried both tin-plate and cast-iron; 
 but it. is well worthy consideration, for 
 pipes of tin-plate, are much more speedily 
 erected, and are cheaper at the ordinary 
 prices, in the proportion of about 7 to 17. 
 One defect, in this arrangement, as com¬ 
 monly executed, is having the pipes, too 
 high above the floors; but they might be 
 placed hear the floor, and yet arranged on 
 the same general principle. This arrange¬ 
 ment possesses a very considerable advan-' 
 tage, for some purposes, over that about 
 to be described, viz. that each floor may 
 be heated separately. 
 
 Arrangement II. for Heating a Cotton-Mill. 
 
 173. The steam from the boiler, in this 
 arrangement, ascends in the vertical pipe, 
 to the highest story, where going along 
 the floor horizontally, to the further end, 
 it descends in a short vertical pipe to the 
 story below, where it is again carried along 
 
HEATING BY STEAM, 191 
 
 horizontally^ and thus is made to descend 
 until it arrives at the bottom. There the 
 water proceeding from, condensation, is 
 allowed to run off by a syphon, and the 
 air is allowed to escape by a stop-cock, 
 near the same place. 
 
 Ohsermtiom. 
 
 Thisr arrangement is exceedingly simple, 
 and is that adopted by Mr. T. Houldsworth, 
 in his cotton-mill (consisting of 8 stories) 
 at Manchester. Although the house be 42 
 feet wide, and the pipes on one side, the 
 heat is found sufficiently uniform, in every 
 part of the floors, for practice, and, in that 
 situation, it occupies little space. 
 
 It is a disadvantage in this arrangement, 
 that no part of the building can be heated 
 separately from the rest. But in a cotton- 
 mill, this is not attended with much in- 
 convemence. 
 
 Messrs. Todd & Stevenson, at Glasgow, 
 have their mill heated by a similar arrange- 
 
HEATING BY STEAm. 
 
 ment, but the pipes are of tin-plate, and 
 were fitted up about the year 1793. 
 
 174. In arranging the steam-pipes for 
 Milgavie cotton-works, a similar mode was 
 followed. There, the steam-pipes require 
 about two hours in the morning,-before 
 they are completely filled with steam. 
 
 Arraiigment III. for Heating a Cottoih-Mill. 
 
 175. In this arrangement, the principal 
 part of tile tubes are vertical, and serve to 
 
 support the floor. 
 
 176. A horizontal pipe conducts the 
 steam from the boiler to the nearest ver¬ 
 tical pipe, and thence it is conducted by 
 the horizontal pipe, to the top of the new 
 vertical pipe, and so on, alternately ascend¬ 
 ing one pipe, and descending the next. 
 Below, it passes from one vertical tube to 
 another by the wider pipes. There are 
 smaller pipes to carry off the water of con¬ 
 densation, and being placed just below the 
 level of the rmder parts of the larger ones. 
 
193 
 
 HEATING BY STEAM. 
 
 , they are kept always full of water, so as 
 to prevent the steam from passing through 
 them. At tihe further end, the water of 
 condensation is let off by a syphon, and 
 the air by a cock or valve, which, in order 
 to allow the air to escape freely, should be 
 as large as the diameter of the steam-pipes. 
 If the number of pillars be not even, then 
 the air-valve should be at the top of the 
 last vertical pipe. 
 
 Observatimis. 
 
 This mode saves the expense of pillars, 
 for supporting the Hoors, but eveiy one of 
 experience, knows the disadvantage of hav¬ 
 ing any apparatus or piece of machinery, 
 so constructed as that, when any parti¬ 
 cular part of it is out of order, it cannot 
 be repaired without deranging the whole 
 system. 
 
 There are many mills, however, fitted 
 up on this plan, which give satisfaction to 
 the proprietors. 
 
 Messrs. Forbes, Low, & Go’s, great mill, 
 which is heated in this way, at Aberdeen, 
 
194 
 
 HEATING BY STEAM. 
 
 requires about ^three quarters of an Hour 
 to let oflF the air and fill the tubes with 
 steam. Messrs. William King & Co.’s 
 mill at Johnston, is also on that plan. 
 There the steam passes through about 400 
 feet of tubes, in 15 or 20 minutes. The 
 tubes should be equally wide throughout, 
 in order that they may fill with greater 
 facility. (See Note B). 
 
 D’welling-Houses^ 
 
 177. There are ygt but few instances 
 
 of dwelling-houses heated by steam, nor, 
 perhaps, would it be eligible to heat small 
 houses separately by it, on account of the 
 trouble it would require to keep a small 
 boiler regularly supplied with water and 
 fhel. But where steam can be obtained 
 from a steam-engine boiler, or where a 
 number of neighbouring buildings could 
 be supplied from one boiler, much might 
 be saved in attendance and fuel, as well as 
 cost of apparatus. In cases where single 
 buildings are large, such as Inns, Hotels, 
 &C. steam might be applied with peculiar, 
 advantage in heating the stair-cases, pas- 
 
HEATING BY STEAM. 
 
 195 
 
 sages, bed-rooms, &c. An- eating-room 
 heated by an open fire only, is often 
 unpleasantly cold to those who sit near 
 the door, while it is oppressively warm 
 to: those who sit near the fire. This 
 inconvenience might be remedied by the 
 use of steam. A very small open fire in 
 that case, would be sufficient to give a 
 cheerful appearance to the room. The 
 particular arrangements of the apparatus 
 proper for dwelling-houses, must de¬ 
 pend much on local circumstances. As 
 the steam may be admitted into vessels of 
 almost any form, the ornamental may be 
 combined with the useful. I am at pre¬ 
 sent, engaged in some experiments, with a 
 view to simplify such arrangements, but 
 am not yet ready to lay the result before 
 the public. 
 
 178. Mr. Lee of Manchester has his 
 dwelling-house heated by steam, conveyed 
 under ground from the boiler of a steam- 
 engine. The stair-case, lobby, and passages, 
 are heated by means of a steam cylinder, 
 placed vertically in the sunk story. The 
 
196 
 
 HEATING BY STEAM. 
 
 Steam cylinder is surrounded by a casing 
 of brick-work, leaving a space of' about 
 two and a inches all round, and hav¬ 
 ing openings below to admit air. This 
 casing is surrounded at some little dis¬ 
 tance, by another cylindrical wall, forming 
 what we may call the well. The coldest 
 ^ being the heaviest, falls to the bottom 
 of the well, and enters by the holes below 
 into contact with the cylinder, where, be¬ 
 coming heated and specifically lighter, it 
 ascends. Tkis circulation of the same air, 
 in a very short time, makes the stair-case, 
 &c. comfortably warm. There is a valve 
 to regulate the admission of the steam into 
 the cylinder. There is also another valve 
 on the top of the casing of brick-work, to 
 regulate the transmission of the heated air. 
 It generally soon becomes so warm, that it 
 is necessary to shut one or other of these 
 valves. 
 
 The dining-room is heated by means of 
 two ornamental cast-iron vases filled with 
 steam, and the bed-rooms by steam-pipes 
 of the same material. 
 
HEATING BY STEAM. 
 
 197 
 
 It may not be improper to mention, 
 that the house is lighted, in a very elegant 
 manner, by cqal gas. 
 
 179. In answer to some inquiries which 
 I made respecting heating of an inn at 
 Johnston, by steam, Mr. M'Naught oblig¬ 
 ingly sent me the following letter: ? 
 
 Johnston, 1th Sept. 1809. 
 
 Dear Sir, - 
 
 In compliance with your request, 
 I now send you a description of the Black 
 Bull Inn, as it is heated with steam.— 
 There is a boiler fitted up in the ordinary 
 way, except the furnace mouth, which 
 is made like a hopper, in order to hold 
 a considerable quantity of coal-gum * or 
 
 dross, and prevents frequent attention to 
 
 the fire, as there may be put in as much 
 at a time as will serve at least half a day, 
 and will need only to be stirred a little 
 with the pocker now and then. The un¬ 
 der flat is heated with triangular pipes, to: 
 imitate a cornice, the place of which they 
 
198 HEATING «Y STEAM. 
 
 occupy in one side of all the rooms; from 
 the metal cornices, a pipe is taken to the 
 Tipper rooms into a sort of chest, which 
 stands upon short feet similar to a desk, 
 and freely admits air below it. They are 
 ornamented in front similar, to carron- 
 grates, &c. in some of the rooms there are 
 two, in others only one, of these chests, ac¬ 
 cording to the size of the rooms. As they 
 are yet hardly finished, and have been 
 tried only a few days, little can be said as 
 
 to the effect. Considering the doors being 
 so frequently opened, &c. a large portion of 
 heated surface has been allowed, about 1 
 foot' to 100. It seems to me, that the. 
 house will be too warm, but it is impos¬ 
 sible to judge accurately till cold weather 
 commences. 
 
 The reason for keeping the under pipes 
 so high as the cornice, was to get the con¬ 
 densed water back into the boiler, as there 
 is no regular supply, what they have is got 
 from the roof, and kept in a number of 
 casks supported in a row above the boiler. 
 And by using the hot water from the 
 
HEATING BY STEAM. 199 
 
 pipes, there is only the waste of evapora¬ 
 tion for to keep up. There is a steam 
 kitchen connected with the boiler, in a 
 pretty advanced state. 
 
 Among other advantages, a dinner or 
 plates, &c. may be kept warm by setting 
 them on the top of the chests, and placing a 
 cover over them. It will also save a servant, 
 during winter at least, and as there is 
 more power in the boiler than necessary, 
 some of the neighbours have been treating 
 to be heated from it.—This you will see 
 will become common in a short time. I am, 
 Dear Sir, 
 
 Yours, &c. 
 
 Fuhlic Buildings. 
 
 180. In. the year 1801, Count Rumford, 
 arranged the apparatus, for heating the 
 Great Lecture-room of the Royal Institu¬ 
 tion by steam, in the following manner: 
 
 The steam is generated in a boiler on 
 the ground floor, and is conveyed by a 
 
200 HEATING BY STEAM. 
 
 copper pipe into the Lecture-room. There, 
 it divides into two branches, and passes 
 horizontally under the seats. 
 
 In order to counteract the expansion 
 of the pipes, there is a drum of thin cop¬ 
 per, placed in the nuddle of each tube. 
 The water of condensation is carried off 
 from the lower part of each drum by 
 small tubes, and conveyed back to the 
 
 boiler. 
 
 The general arrangement here seems 
 good. The lower part of the room being 
 heated, the other parts must of course, be. 
 sufficiently warm. The plan of the expan¬ 
 sion drums, although ingenious, is objec- 
 .tionable on account of expense, as well as 
 on accoimt of their occupying a very large 
 space. 
 
 We are yet much in want of examples 
 of heating public buildings by steam, but 
 it is highly probable that it will soon be¬ 
 come more general. The mode in which 
 Mr. Lee heats his stair-case,'might perhaps 
 
HEATING'BY STEAM, . 201 
 
 be . applicable -witli advantage in many 
 cases of public buildings. Much of what 
 is said respecting dwelling-houses may be 
 applied here. 
 
 Bath. 
 
 179. The late Mr, Boulton of Soho, was, 
 
 I believe, the first who used steam for 
 heating the water for a warm bath, which, 
 I am told, gave rise to the method of 
 heating the vats, &c. of the dye-house pf 
 Messrs. Wormauld & Gott of Leeds. 
 
 At Helensburgh, the water for the warm 
 baths is, as usual, heated in a boiler, and 
 ■ admitted as it is wanted. Steam from the 
 same boih r, serves also to heat the bath¬ 
 rooms, to ' ach of which it is communicat¬ 
 ed by a small pipe, to a vertical tube of 
 tin-plate about 7 inches diameter, and 4 
 feet long. 
 
 I shall not at present enter" into the 
 details of heating water by steam, as that 
 subject may furnish matter for a separate 
 
General Explanation of Pfofe 2. 
 
 Fig. 1, represents the method of connecting pipes hy 
 Ae^ of Jlancha, (Art. 153). 
 
 Fig. 2j tpigat anJfaucet joint, (Art. 154.). 
 
 .Fig. 3, ihimikjoint, (Art. 155). 
 
 Fig. 4, a method of connecting spigot and faucet pipes, 
 where they are to have a round turn or an angle, (Art. 
 156). , 
 
 Fig. S, saddlejoiht, (Art. 157); 
 
 Fig. 6, slipping joint to allow the pipes to expand, (Art. 
 
 159). 
 
 Fig. It methods of maiing jo'mii on vertical pipes sup- 
 
 porting floors, (Art. 160). 
 
 Fig. 8, steam boiler with apparatus for feeding, &c. 
 (Art. 162). 
 
 Fig. 9, reprints the inode of allowing the air to escape 
 by a pipe at the termination of the steam pipes, and of tak¬ 
 ing off the mater of condensation by means of a syphon, 
 (Art. 168). 
 
 SND OP PART SECOND.' 
 

 DRYING, 
 
 AND 
 
 HEATING, 
 
 BY STBAM. 
 
 INTRODUCTION. 
 
 Hitherto, we have considered those 
 cases only where the temperature, does not 
 exceed 70° or 80° of Fahrenheit’s ther¬ 
 mometer, and where heat only is required; 
 but there is another application of stesun, 
 of which we come now to treat, I allude to 
 
 its use, as a substitute for drying-stoves. 
 
HEATING BY STEAM. 
 
 Steam was many years ago tried at 
 Leeds for that purpose; but, for reasons 
 with which I am unacquainted, the plan 
 was abandoned. 
 
 A method of drymg certain kinds of 
 muslins, by wrapping them round cylinders 
 of tin-plate, has, for several years, been 
 successfully practised by bleachers, in the 
 vicinity of Glasgow. The first idea of 
 them, I believe was suggested by Ml*. 
 John Burns pf P^sley, in conversation with 
 Mr. Laird, and Mr. Tennant, now of Glas¬ 
 gow. It was first put in practice by the 
 last mentioned gentleman, at the Darnly 
 bleaching works, about the year 1793, 
 about twelve months before it was adopted 
 at any other work, A description of this 
 method of drying muslins, may be seen 
 in “Dr. Ree’s Cyclopedia” article, “Bleach¬ 
 ing.” Steam-rollers have also been suc¬ 
 cessfully used by calico-printers, for drying 
 their goods; but somewhat different in 
 their modification, from those above al¬ 
 luded to. 
 
HEATING BY STEAM. 205 
 
 181. Mr. Loiinds of Paisley, I believe, 
 was the first who succeeded in using steam 
 as a substitute for a drying-stove, to dry 
 goods, stretched on frames. This he has 
 done these several years, for the finer kinds 
 of muslins. 
 
 The temperature required for such goods, 
 however, is much lower than that required ■ 
 for drying the thicker kinds of cotton-cloth, 
 such as chequered handkerchiefs, called 
 pullicates. Messrs. Muir, Brown, & Co. 
 at Glasgow, were the first who succeeded 
 in the application of steam, for this pur¬ 
 pose, and also for drying dyed and bleached 
 yarns, where the temperature required is 
 still higher. They made the first trial of 
 their drying-rooms on March 26th, 1808/ 
 
 Mr. Muir informs me, that though they 
 formerly gave out their pullicates to be 
 bleachedi by some of the best bleachers in 
 this part of the country, that they never 
 had the eolours of their goods in the same 
 perfection which they ilow have, and which 
 
 improvement they attribute entirely to the 
 
206 HEATING BY STEAM. 
 
 superior effect of the steam, a,nd that the 
 more experience he has, he is the more 
 convinced of this advantage froin the 
 steam-heat.- 
 
 I apprehend the superior effect, with 
 regard to colour, of this mode of drying, 
 arises from the difficulty of raising steam- 
 heat to such a degree as to be injurious; 
 as well that no gas which can be hurtful 
 to the colours, is emitted from the steam- 
 pipe. In drying-stoves, on the contrary, 
 the heat is often raised too suddenly to a 
 very high temperature, which gives a harsh 
 feel to the goods; and in such stoves, the 
 air is often much Injured by gas emitted 
 from the coackle and the flues, which must 
 certainly have a great influence on the 
 colour of the goods.* 
 
 • A gentleman extensively engaged in calico-printing, favours me 
 with the following note: 
 
 “ In confirmation of the above, I suppose the superiority of the 
 colours in the drying of the pullicates, and alto in the operations of 
 calico-printing, called paddir.g, arises from the facility with which 
 steam-heat may be gently and equably applied. By its being so easily 
 regulated to the degrees of the thermometer, it possesses evidently a 
 more convenient applicability to manufacture, where the quality of the 
 commodities depends on the degree of heat, than the other modes,” 
 
HEATING BY STEAM. . 
 
 Mr. Mair gives me the following fur-' 
 ther information, which must be agreeable 
 to every friend to humanity, that the peo¬ 
 ple who now vvork in his drying-rooms, 
 Were formerly employed in working in a 
 stove heated in the common Way, at Which 
 time, they had a very emaciated unhealthy 
 appearance; but since they haYe been 
 employed in the rooms heated" by steam, 
 
 they have become healthy, and their aspect 
 has changed most materially for the better. 
 
 • 182. About this period, ,Mr. Richard 
 Gillespie, of Anderston, notwithstanding 
 the prejudices of other calico-printers, who 
 predicted that the heat proceeding from 
 steam-pipes, was not of a kind that would 
 
 Since this sheet -went to press, Mr. Muir made the following experi¬ 
 ment, which seems to prove that it is the^aj, only, in common stoVes,' 
 which injures the colour. He took a hank of scarlet yam and divided 
 it into three parts. Two of tliese parts were then wetted. One of the 
 
 wet parts was put into a common drying-stove at 128“ of Fahrenheit. 
 
 The other he laid on a steam-pipe, which raised the thermometer to 
 ISS®. When dry, the three parts were compared. The colour of 
 that which was in the stove was much injured, while that which was 
 on the steam-pipe retained the same shade and lustre with the part 
 which had not been wetted. Lilac, purple, pinfe, and other more deli- 
 oate colours, would have been much more injured than scarlet. 
 
208 HEATING BY STEAM. ' 
 
 ever answer in the practice of calico-print¬ 
 ing. They required, they said, a, dry hcat^ 
 which they conceived could never proceed 
 from steam, a fluid moist in its own nature, 
 forgetting that heat is not altered by being 
 combined with other kinds of matter, and, 
 that in passing through the pipes, if pro¬ 
 perly executed, the heat must leave the 
 moisture behind. Mr. Gillespie, notwith¬ 
 standing those prejudices, made the attempt 
 
 first, in his copper-plate house, and suc¬ 
 ceeded to his most sanguine wish. His 
 success in this instance, prompted him tp 
 apply steam to. his block-printing shops, 
 also in which, he has been equally suc¬ 
 cessful. 
 
 Previously to these applications, besides 
 heating his warehouse, he had applied it 
 to the heating of his calenders. For which 
 
 purpose, the steam is conveyed about 93 
 
 yards under ground*. 
 
 • I tdieve the late Mr. John Miller of Glasgow, was the first who 
 applied steam to the heating of a calender, which he did in the month 
 of Inly 1805. 
 
 This mode of heating calenders by steam, is found a very great 
 improvement, not only as it saves time, but improves the appearance 
 of the goods. 'When heated with red-hot iron heaters, the goods had 
 comparatively a harsh impoverished, dry, brittle feel. 
 
HEATING BY STEAM. 
 
 209 
 
 Messrs. Leys, Mason & Co. of Aberdeen j 
 also about this time applied steam (on 
 principles similar to Messrs. Muir, Brown, 
 & Co.) to the purpose of drying cloth at 
 their bleaching works. 
 
 Dd 
 
210 
 
 HEATING BY STEAM. 
 
 SECTION I. 
 
 CASE L— Drying-House. 
 
 183. Consists of a room 8 feet high, 
 of an irregular figure, containing about 
 9472 cubic feet of space, and is heated by 
 means of horizontal steam-tubes of tin¬ 
 plate, about 2 feet from the floor. These 
 tubes are arranged in two separate groups, 
 so as to be immediately under two frames, 
 on which the goods are stretched. 
 
 Cubic feet of space,--94-72. 
 
 Surface of tube,-■*----S81.1 feet. 
 
 Space heated by one foot surface of tin-tube, 16.2 cub. feet. 
 
 But as cast-iron emits 2» times more heat 
 than tin-plate, (Art. 140.) the less tube 
 would have served, in which case, the 
 space heated by one foot surface, would 
 be represented by 25 times 16. That is, 
 40 cubic feet of space heated by 1 super¬ 
 ficial foot of cast-iron, temperature 90°. 
 
'heating by steam. 211 
 , . Observations- 
 
 In summer, this room is sometimes at 
 100°; in winter, generally 90®. 
 
 On the 18th of November, 1808, it was 
 only 80°, the external air at the time being 
 42°, being a difference of 38 between the 
 external and internal air.. 
 
 - The goods dried here, are thin muslins, 
 stretched on frames, the air being agitated 
 b]?^ a- pendulous fan. 
 
 It is employed first, strictly as a heating 
 stoye, and the windows kept all close shut, 
 imtil the vapour from the goods begins to 
 condense on the windows. As soon as 
 the steam begins to obscure the glass, the 
 attendants open them to let off the vapour, 
 and when that is done, they shut them 
 again; thus alternately heating and venti¬ 
 lating. 
 
 This mode appears to me exceedingly 
 judicious; formerly, there was no persua-r 
 sion could make operatives see the pro¬ 
 priety of ventilation, in a drying-stove. 
 
212 HEATING BY STEAM. 
 
 They now find that ventilation is neces¬ 
 sary to a certain degree, which degree Mr. 
 Dalton (in his Letter of 14th June, 1808,) 
 says, “ has net yet, I conceive, been de~ 
 terrnined.” Query^ Whether may not the 
 appearances on the glass, now mentioned, 
 serve as some indication of the degree? A 
 hygrometer might, probably, be of very 
 great use in situations of this kind. (Art. 
 82.) 
 
 One of the most scientific and experi¬ 
 enced bleachers we have, informed me, 
 (April, 1806,) that stoves were much im- 
 prpvedjby admitting a more free circulation 
 of air, and, in that case, 80°, or even 70°, 
 was sufficient for purposes which required 
 
 100®, in a dose house. 
 
 '■; ;flt is evident, that the heat operates on 
 the cloth, by evaporating the water, but 
 after it has thus suspended the moisture, 
 if it be not allowed to escape somewhere, 
 it must remain, in the room, and retard 
 the process. In other words, it is keeping 
 the goods in a damp, although warm., 
 atmosphere. 
 
HEATING BY STEAM. 213 
 CASE n.— Drying-House. 
 
 184. This drying-house is heated by 
 horizontal cast-iron steam-tubes, in such 
 proportion, that one foot surface, heats 
 about 80 cubic feet of space. 
 
 The steam is kept in the tubes in the 
 night, as well as in the day. 
 
 The temperature in November 1807, 
 was 100°, 
 
 CASE JS..—-Drying-Rooms. 
 
 185. In this case, there are two rooms 
 for drying by steam, the one for cloth, 
 and the other for yarn. 
 
 These rooms are both on the same floor, 
 one story above ground. The steam is 
 generated in a boiler, which supplies a 
 steam-engine and other purposes. That 
 for the yarn, requires to be considerably 
 hotter than that for the goods. 
 
 The whole of these steam-tubes are of 
 cast-iron, eight inches external diameter, 
 
2hi HEATING BY STEAM, 
 
 and are joined by thimbles where they are 
 straight^ by saddle joints at the branches, 
 and by spigot and faucet joints at the angles. 
 (See Art. 154—157.) 
 
 The inost of the joints are made with 
 iron cement (Art. 158). Lead was tried for 
 some of them, but was found not to make 
 a lasting joint. 
 
 The tubes are placed near the floor, in¬ 
 clining downwards as they recede from 
 the boiler. In order to allow them to move 
 freely in expanding and contracting, they 
 are supported by hollow cast-iron rollers, 
 which rest on blocks of wood, rounded in 
 a contrary direction on their under side, 
 •which rests on the floor. Thus forming 
 a kind of universal joint. 
 
 Where the steam-tubes come in contact 
 with the walls of the building, pieces of 
 tin-plate are interposed, in order to save 
 the heat. (See Art. 90 and 144.) 
 
HEATING BY STEAM. 
 
 215 . 
 
 The rooms are both eight feet high. 
 The yarn-room contains 4,224 cubic feet 
 of space. 
 
 '' Cubic feet of space heated by 1 super¬ 
 ficial foot of steam-pipe, 
 
 Cloth room tontains 5,952 cubic feet. 
 
 Cubic feet of space heated by 1 super¬ 
 ficial foot of steam-pipe, 23fi. 
 
 There is a valve, where the steam-con¬ 
 ductor branches off from, the boiler, laden 
 just to that degree, that when the steam 
 becomes weak, it shuts, and allows the 
 whole of it to go to supply the steam- 
 engine. 
 
 Observations. 
 
 These rooms were first tried on the 
 26th March, 1808; the walls were then 
 damp, from having been recently plaistered. 
 
 The external air was-42°. 
 
 The cloth-room - --91°. 
 
 The yai-n-room-99°. 
 
216 HEATING BY STEAM. 
 
 The steam jDoiler is only kept boiling 
 during the day, and is rather small to 
 supply the various purposes to which it is 
 applied, so that the rooms are not kept nearly 
 so hot as otherwise they might be. There 
 are also several of the panes of glass 
 broken, and often a great deal of wet 
 goods in the rooms; but, notwithstanding 
 those disadvantages, the temperature is 
 generally from 86“ to 96°. The yaim 
 room is commonly about 10“ higher than 
 that for cloth. The former, in summer, 
 was often as hot as 120°. 
 
 Notwithstanding the lowness of the 
 
 temperature, these two rooms drj as much 
 
 goods, and. with as few hands, as any stoves 
 of the same dimensions, even where the 
 temperature is much higher. And it is 
 pleasing to reflect, that the people working 
 in the steam rooms, are much more 
 healdiy and comfortable, than those in 
 the contaminated air proceeding from 
 stoves, as commonly constructed for such 
 purposes. 
 
HEATING BY STEAM. 217 
 
 The proprietors assure me, that they are . 
 more and more convinced of the superior 
 effects .of steam, with respect to the colour 
 and finish of the goods, as well as with 
 the much greater economy of the process; 
 and, that' they are so much convinced of 
 the superior colour and finish, that al¬ 
 though it voere at double the expense of stove 
 heat, the)'' would still use it in preference. 
 
 On the 14 th of January, 1809, the tem¬ 
 perature of the external air being 29°, 
 
 The cloth room was-86°. 
 
 The yarn room was - - — 101°. 
 
 Although the windows were partly open, 
 and a great deal of wet goods in the rooms. 
 
 The attendants find here, that the ad¬ 
 vantage of a circulation of air, depends 
 very much upon the state of the. weather. 
 When it is damp, they find it is best to 
 keep the windows shut, and to raise the 
 steam heat; but, on the contrary, when 
 the weather is dry, a free circulation of 
 
218 HEATING. BY STEAM. 
 
 air is of much greater consequence than a 
 high temperature. 
 
 CASE.JSf.—Calico Printing. , 
 
 186. The steam is generated in a boiler 
 of about twenty horses’ power, which sup- 
 phes a steam-engine of. ten horses’ power. 
 The steam is conveyed about ninety-three 
 yai'ds imder ground, to heat two calenders, 
 and warm counting-houses and warehouses. 
 It also heats the copper-plate house, block- 
 printing shops, and heats water for the 
 processes of branning, dyeing, &c. 
 
 I. Copper-Plate House. 
 
 The copper-plate presses are driven by 
 the steam-engine, and stand in a room one 
 story above the ground. 
 
 : About six inches from the ceiling, is a 
 horizontal steam-tube, six inches exter¬ 
 nal diameter. 
 
 The garret above the presses, is occupied 
 for drying the cloth, as it passes from the 
 presses; which arrangement allows-the 
 
HEATING BY STEAM. 219 
 
 printers to work iii a moderate tempera¬ 
 ture, while the goods are drying in a tem¬ 
 perature much higher. The garret is heated 
 partly from the heat which rises from the 
 press-room, and partly from a Horizontal 
 tube, seven inches external diameter. 
 
 But, as there is a communication be¬ 
 tween the rooms, they ought to be. taken 
 together. Therefore, press-room and garret 
 taken together,. the space heated by 1 foot 
 surface of steam-tube is 181 cubic feet. 
 
 On the 12th February, 1808, the, tem¬ 
 perature of the external air, early in the 
 morning, was 27°, about eleven o’clock, it 
 was 30°. 
 
 The press-room-- — 64°. 
 
 The garret---- 73°. 
 
 Notwithstanding the coldness of the ex¬ 
 ternal air, the cloth from the presses was 
 made, to use the overseer’s expression, bofte 
 dry^ and the operations going on to the 
 complete satisfaction of the proprietors. 
 
220. HEATING BY STEAM. 
 
 12di of March, 1808, the thermometer 
 in the garret, stood at 105°. 
 
 2. BlacJc-Printhig Shops. 
 
 The block-printing shops are each heated 
 by a horizontal steam-tube, Ilf inches 
 diameter, of cast-iron, about 24 feet from 
 each floor; and the temperature, when 
 there is a suflBciency of steam, is usually 
 about 80°. 
 
 Here 90 cubic feet is the space heated 
 by one foot surface of steam-tube. 
 
 Obsei'vations. 
 
 This mode of heating for this kind of 
 printing, gives equal satisfaction with that 
 for the copper-plate department. 
 
 It is proper to have a boiler of sufficient 
 capacity, in order that the steam may be 
 used for all the various purposes to which 
 it is applicable, in the difierent processes 
 in calico-printing. In this particular case, 
 the proprietor informs me, that since he has 
 used steam as a substitute for stoves, &c, 
 the saving produced has been very great. 
 
HEATING BY STEAM. ' 221 
 
 SECTION II. 
 
 Of the difference of Temperature hetxceen the ex¬ 
 ternal Air and the intental Air of a Building 
 heated by Steam. 
 
 187. Hoping that it might be satisfac¬ 
 tory to many, to know whether the differ¬ 
 ence of temperature between the external 
 and the internal air of a building heated, by 
 steam, was nearly constant., and conceiving,. 
 that it might lead to some useful inference, 
 
 I was induced to have the subject experi¬ 
 mentally, examined. This examination 
 Mr. H. Houldsworth had the goodness to 
 permit me to make at one of his mills in 
 Ariderston; the result of which is given 
 in the following table. 
 
 From the table, it will appear that the 
 difference is far from being constant, and 
 that it is greatest when the air is coldest. 
 
322 
 
 HEATI^IG BY STEAM. - 
 
 Table of the state of the Thermometer in the open 
 Air, and in a Colton-MUl, the property of H. 
 HouUsworth, Esq. each day at 12 o’clock. 
 
. HEATING BY STEAM. 22S 
 
 SECTION III. 
 
 Of the proporlimi hetijoeen the Surface of Steam- 
 Pipe, and the Heat produced. 
 
 188. It is of considerable practical im¬ 
 portance, to be able to calculate the quan¬ 
 tity of steam-pipe which will be necessary 
 to produce a given temperature. It rnust 
 be,confessed, however, that such an estimate 
 admits not of absolute precision. 
 
 The temperature will, obviously, not 
 increase in a ratio nearly so high as the 
 increase of surface of pipe. Foi', suppose 
 a room already at 70°, and that, by means 
 of a cock or valve, we suddenly introduce 
 steam into another tube, , which is equal to 
 that already'producing the 70°, the differ¬ 
 ence of temperature between the external 
 and internal surfaces of the second pipe, is 
 much - less than it was in the first. Of 
 course, the condensation must go on much 
 more.slowly, and were the air at 112°, and 
 the steam of the same density as the. 
 
224 HEATING BY STEAM. 
 
 atmosphere, no condensation at all could 
 take place. The facts which are collected 
 in the annexed table, will, however, enable 
 the practical reader to approximate toward 
 the truth; and he will there see, perhaps, 
 nearly the maximum temperature which 
 is to be expected in any case in practice, 
 where the rooms have but little ventilation. 
 Where the ventilation is great, it follows, 
 that the efiect of the sni'face of steam-tubes 
 must be lessened. In this table, I WOUId 
 beg leave to direct the reader’s attention 
 to the difference between the ternperature 
 of the external and internal air, as being 
 likely to furnish a guide, in calculating the 
 quantity of pipe requisite in any given 
 case. 
 
 In order to form some idea of the greatest 
 heat which could probably be expected 
 from steam-tubes, when the surface should 
 be very great, I made the following experi¬ 
 ments, which were repeated, with nearly 
 the same results. These results are, for 
 the sake of bringing the whole of this part 
 of the subject into one view, given in the 
 table. 
 
HEATING BY STEAM. 
 
 Enfermient 1st. 
 
 189. A cylindrical tin-plate canister, 
 two inches diameter, and five inefies long, 
 with a small projecting rim at one end, to 
 receive a cork, A Fahrenheit’s thermom¬ 
 eter was inserted through the cork, so that 
 its bulb was nearly in the centre of the 
 canister. It may be proper to reimark, 
 that the tin-plate was become dim, from 
 having been long exposed to the air. 
 
 This canister was plunged its whole 
 depth into boiling water. The thermom¬ 
 eter, which previously stood at 60°, rose 
 to 160°. The barometer stood at 29.5. 
 
 Obsermtiojis. 
 
 In this and the following experiments, 
 upon emersing the canisters into the 
 boiling water, part of the air v/hich was 
 expanded by the heat, escaped between the 
 cork and the thermometer. But this is 
 what must occur in practice on the great 
 scale, as the ratified air must escape from 
 an apartment, when it becomes heated. 
 
 ■ • F f 
 
HEATING BY STEAM. 
 
 The contents of the canister was 0.00909 
 cubic feet. 
 
 The surface exposed to the hot water, 
 0.2563 superficial feet. 
 
 . Space heated proportionate to one super¬ 
 ficial foot of surface exposed to the hot 
 water, 0.035466. 
 
 Ex^p^riment 2d. 
 
 ' 190. The same canister, coated in the 
 inside with lamp black and size, all other 
 circumstances being as in the first experi¬ 
 ment, was immersed its whole depth in 
 boiling water. The thermometer rose to 
 190". 
 
 Observaiions. 
 
 Here we see the increase of effect 30 
 degrees, occasioned by coating the surface 
 of the tin-plate with lamp black. (See 
 Art. 83.) 
 
 Expennienl 3d. 
 
 191. The canister, all other circum¬ 
 stances as in experiment 2d, was half im- 
 
HEATING BY STEAM. 
 
 mersed ia boiling water. The thermom¬ 
 eter rose to 176°. 
 
 . c: Observations. 
 
 The space heated proportionate to one 
 superficial foot of surface exposed to the 
 hot water, which, in this case, was double 
 that of experiment 2d, or 0.070932, which 
 alteration lowered the thermometer 24°. 
 
 Experiment 4-fli. 
 
 192. A small canister of tin-plate, of 
 an elliptical form, about 2.75 inches deep, 
 having its greatest diameter 1.9 inches, 
 and its least-0.8. The tin-plate, as in the 
 cylindrical canister, was tarnished. A 
 thermometer was also inserted through a 
 cork. The canister being immersed into 
 boiling water, the thermometer rose to 
 190°. 
 
 Experiment 5th. 
 
 193. The 4th expeiiment repeated, with 
 this difference only, viz. that the inside of 
 the canister was coated with lamp black. 
 The thermometer rose no higher than 
 190°. 
 
HEATING BY STEAM. 
 
 Ohservations on. Experiments Uh and 5th. 
 
 In the 4th and Sth experiments, the con¬ 
 tents of the canister was 0.001899 cubic 
 feet. 
 
 Surface exposedtothehot water,0.10Y291 
 superficial feet. 
 
 Space heated proportionate to one super¬ 
 ficial foot of stuface exposed to the hot 
 water, .017699. 
 
 In so small a space, compared with the 
 surface, coating appears to have no influ¬ 
 ence on the projectiag power, for the re¬ 
 sult, 190°, in both these experiments, is 
 the same. 
 
 , We may infer from Experiments -Sd, 
 4th, and 5th, that the maxmum heat to be 
 produced by steamy where the air is not conjined, 
 is 190 degrees. 
 
heating by steam. 
 
 194. Table showing the Heat produced from dif- 
 ferent Troportions of Steam-Pipe. 
 
 
 wanned by 1 
 
 of steam-pipe. 
 
 
 Inter- 
 
 nalAir. 
 
 Difference 
 of temper- 
 
 Chapel at Port-Glasgow, 
 
 400 
 
 40 
 
 60 
 
 20 
 
 Cotton-Mills, . . - 
 
 200 
 
 34 
 
 70 
 
 36 
 
 Case I. (Art. 183.) - 
 
 40 
 
 34 
 
 90 
 
 56 
 
 Case II. (Art. 184.) - 
 
 80 
 
 34 
 
 loq 
 
 66 
 
 Case III. (Art. 18S.) 
 
 1 
 
 
 
 
 cloth-room, ... 
 
 23 
 
 42 
 
 91 
 
 49' 
 
 
 
 29 
 
 86 
 
 55 
 
 Do. yarn-room, - - - 
 
 16 
 
 42 ' 
 
 99 
 
 57 
 
 
 
 29 
 
 101 
 
 72 
 
 Experiment 2d, (Art. 
 
 
 
 
 
 190.). 
 
 0.03S466 
 
 60 
 
 190 
 
 130 
 
 Experiment 3d, (Art. 
 
 
 
 
 
 190.). 
 
 1 0.070932 
 
 60 
 
 176 
 
 116 
 
 Observations on the Table. 
 
 The 2d and 3d experiments only, are 
 inserted because the 2d shows the maximum 
 heat, (Art. 193,) and the 3d, the altera¬ 
 tion of temperature occasioned by heating 
 double the space by the same surface. 
 All the cases in the table have the surface, 
 either coated, or, what is equivalent, of 
 cast-iron, (Art. 142). 
 
HEATING BY STEAM. 
 
 SECTION IV. 
 
 MisceUaneous Olseroations. 
 
 195. Attempts have been made, to 
 
 bring a current of air over steam-pipes, 
 or through, pipes included in o^ers, filled 
 ■with steam, in order, by quickening the 
 condensation, to make a less surface of 
 steam-pipe heat an equal space. Mr. 
 Roberton tried this plan, by enclosing the 
 pipes in tnmks, and producing a current, 
 by the rarefaction of the air *. I have at¬ 
 tempted the same thing, by increasing the 
 current of air by machinery, but I cannot 
 
 • Thee trials were made with pipe of tin-plate, induded in 
 wooden tranks, at one end of the rooms. The air entered the trunk 
 at the floor, and escaped at the ceiling. Mr, Roberton found that the 
 heat was, to a certain degree, increased by this circulation, and that the 
 temperatnre, at the further end of a room of great extent, was nearly 
 eijnal to what it was near the trank. From the pipes being made of 
 tin-plate,- however, they required frequent repair, which rendered the 
 wooden trunks about them inconvenient, and for that reason they were 
 removed. Hzi it not been from this dtcnmstance, he is of opinion, that 
 
 conaderable advantage would have been derived from the trunks, and 
 
 would recommend them for cast-iron pipes, which would not require 
 the frequent repair necessary, where the' pipes were made of tin-plate. 
 
HEATING BY STEAM. 231 
 
 say, that much practical advantage has 
 resulted from these trials, (see Note C.) 
 We saw, however, (Art. 178.) that Mr. 
 Lee had successfully employed the prin¬ 
 ciple of rarefaction, in heating part of his 
 dwelling-house, and it is probable, that 
 
 this principle will be more generally ap¬ 
 
 plied. 
 
 It has been proposed by some, to heat 
 the external- air, and throw it into the 
 apartments, in a manner similar to some 
 kinds of stoves, supposing, that thus by 
 combining ventilation with heatmg, it would 
 be more salubrious. But this would be 
 obtaining heat at a great expense of fuel, 
 and be losing one very important advan¬ 
 tage which attends heating by steam, 
 viz. that the heating may be kept perfectly 
 separate from the ventilating process, so . 
 that each may be managed separately, and 
 no more heat nor ventilation given than 
 what is just proper. Whereas, on the 
 other plan, there must always be nearly 
 the same ventilation, whether the external 
 air be dry or damp, warm or cold. When 
 
232 HEATING BY STEAM, 
 
 damp, a great quantity of moisture must 
 be thrown into the building, which will 
 require additional heat to suspend it, in 
 order to prevent it from being injurious, 
 and when the air is dry, the current of 
 air. will carry in dust along witk it. I 
 would, therefore, recommend producing 
 the current from the rarefaction of the air 
 •within the building, and ventilating by the 
 window, or other proper openings for the 
 purpose. 
 
 Mr. Houldsworth found, that the maxi¬ 
 mum heat to be produced, by the rarefac¬ 
 tion, was about 140 degrees. 
 
 196. Some have apprehended, that heating 
 by steam might be inconvenient, on ac- 
 cotmt of the very great heat which would be 
 felt for some feet round the pipes; but 
 this is not the fact, for even when they are 
 not included in any kind of air-trunk, as 
 soon as a particle of air becomes heated, 
 being specifically lighter, it has a tendency 
 to ascend to the ceiling of the apartment. 
 The warm air first accumulates there, and 
 
HEATINXJ'BY STEAM- 233 
 
 gradually descending, as is often visible 
 in a room, when warm air enters, mingled 
 with smoke. The cloud first appears 
 along the ceiling, and' then gradually 
 descends, keeping nearly a uniform sur¬ 
 face telow. 
 
 That no inconvenience arises in practice, 
 we have a full proof, in the case of an exr 
 tensive cotton-mill in Manchester^ (see 
 Art. 173.) which is 42 feet wide. The 
 steam-pipes go along the floor on one side 
 only^ and although the yarn spun in this 
 mill be remarkably fine, no difference of 
 temperature is experienced, which, in the 
 smallest degree, affects that delicate pro¬ 
 cess. ' 
 
 197. When speaking of spigot and faucet 
 joints^ (Art. 154.) I omitted to mention, 
 that it seems a good method to cast the 
 faucets thin, and to hoop them with 
 slight wrought-iron, put on at a low red 
 heat. The thinness makes the faucets 
 ekpand along with the spigot, while the 
 hoop gives strength, to allow the cement 
 to be firmly driven into the joint. 
 
 G g 
 
23;^ HEATINGvBY STEAM.- 
 
 ■ 198. In Art. 166, it is mentioned, that 
 a glass tube is sometimes used, to show the 
 height of the water in the boiler. This 
 simple contrivance, is, by some, applied for 
 the farther very important pUtpOSGS of 
 measuring the heat produced by the fuel 
 employed in a given time, and showing 
 the quantity of steam used. Great ad¬ 
 vantage rnay arise from ascertaining these 
 points, Thus, one kind of fuel may be 
 compared with smother. Using the same 
 fuel, it will show the comparative effects 
 of different states of the furnace, and dif¬ 
 ferent modes of treatment. It . also shows 
 accurately; the quantity of steam which a 
 steam-engine is using, according to die 
 order in which it is kept. It may, there¬ 
 fore, be proper to give a more detailed 
 explanation of the mode of using this 
 ingenious connivance. ’ 
 
 ,, The most simple and accurate mode of 
 comparing one kind of fuel with another, 
 is, to measure die quantity of . water-which, 
 under the same circumstances, equal 
 weights of each will evaporate, (see Ar- 
 
HEATING BY STEAM. 235 
 
 tides 45, 52—70, and 111.) Now, by- 
 having a scale attached to the glass tube, 
 and knowing the dimensions of the boiler, 
 opposite each of the divisions on the scale, 
 it becomes easy to form a table, which 
 will readily show the number of cubic 
 feet or inches, to which each division of 
 the scale is equal. 
 
 At the most convenient time of each 
 day, (which in many manufactories Will 
 be the dinner hour,) put as much extra 
 water into the boiler, as wilh allow it to 
 boil for two hours, without getting any 
 supply of water whatever. This being 
 done, let every thing, excepting the feed¬ 
 ing apparatus of the boiler, be set to work 
 as usual for two hours. The scale will, in¬ 
 dicate the cubic feet of water, which, dur-. 
 ing that period, has been evaporated; a 
 register of which may be kept, from which 
 many useful practical inferences may be 
 drawn. . 
 
 . The tube should be a common bar- 
 rometer tube, of a pretty large bore, and 
 
236 HEATING BY STEAM. 
 
 •the thinner it is, it will be the less liable 
 to break from unequal expansion. 
 
 199. Care should be taken; to have all 
 
 the pipes about the boiler sufficiently large, 
 to insure the prompt action of the feeding- 
 apparatus, and to prevent them from the 
 risk of choaking, by any extraneous matter 
 which may be in the boiler. 
 
 200. The pipes also, which are to 
 
 communicate steam to a distance, should 
 be made sufficiently large, the sooner 
 to fill the more distant parts of the ap¬ 
 paratus. When the pipes are small, the 
 surface being great in proportion to the 
 contsuned steam, the condensation goes on 
 very rapidly, and retards the progress of 
 the steam. •: ' 
 
 201. In situations where heat is not 
 wanted from the conducting pipes, it will 
 be proper to defend them from the atmos¬ 
 phere. This may be efficaciously done, 
 by enclosing them within tubes of tin¬ 
 plate, leaving a space all round, of about 
 
HBATING BY STEAM. 
 
 aa inch between the steam-pipe and-the 
 tin-tube, (see Articles 90—96, and. 144). 
 
 But should this mode be thought too 
 
 expensive, a cheaper method may be 
 adopted, that of wrapping the steam-pipes 
 round with a considerable thickness of 
 straw ropes, putting a coating over them 
 of fine plaisterJime, and, after it is drjr, 
 washing them over with lime-water, in 
 order to fill up any little cracks -which 
 may appear. 
 
 202. Where there is fom^d from experi¬ 
 ence, to be too much heat in one place of a 
 building, and too little in another, tin-tubes, 
 as above described, may be used, al¬ 
 lowing a current of air to pass between 
 them and the steam-pipes, which heated 
 air may be conveyed to any higher situa¬ 
 tion, by means of a pipe of tin-plate. 
 
 These covers may be made capable of 
 increase or diminution, by various contriv¬ 
 ances, such, for instance, as forming them 
 on the principles of a sliding spy-glass, as 
 
238 HEATING BY STEAM. 
 
 is done in-fhe countinig-room of the print¬ 
 ing-house of Messrs. James Ballantyne 
 
 &Xo. Edinburgh. 
 
 -Brick-work, in some cases, may be used 
 for enclosing steam-pipes, instead of the 
 tin-plate. 
 
 203. A great saving of fuel may be ob¬ 
 tained, by using double sashes in the 
 windows, a practice common on some 
 parts of the Continent. 
 
 • 204. We saw, (Art. 174 and 176.) that it 
 requires a considerable time, where there is 
 a great length of steam-pipes, to expel the air 
 from them, and to fill them with steam. To 
 obviate this inconvenience, Mr. H. Houlds- 
 worth' proposed a plan, of applying a 
 pump to the pipes, worked by a steam- 
 engine. - First, to expel the air, which 
 would allow the steam speedily to fill the 
 pipes. Afterwards, it would serve the 
 purpose of forcing back the ‘water of con¬ 
 densation. to the boiler, which would pro- ■ 
 duce some saving of fuel; for it, at present. 
 
HEATING BY STEAM. 289 
 
 estapes nearly at the boiling-point, while 
 the boilei* is supplied with water from the 
 
 air-pump of the. steam-engine, about' 100 
 
 degrees colder. Mr. Houldsworth’s plan 
 would be attended with' a further saving 
 of fuel, for, by the common mode, a uni¬ 
 form heat cannot be maintained, unless 
 there be a constant discharge of a .small 
 quantity of steam from the extremity, of 
 the pipes, (Art. 168.) but the forcing-pump, 
 by occasioning a constant circulation of 
 steam in the pipes, would ensure a uni¬ 
 form heat, without any loss of steam. 
 This plan has hot yet, however, been 
 brought to the test of experience. 
 
 205. The. water of condensation, being dis¬ 
 tilled water, it may often be , of use to col¬ 
 lect it for washing or other purposes, for 
 which soft pure water is desireable. 
 
 206, There is considerable difficulty in 
 obtaining accurate data, to compare the 
 expense of fuel, in heating by steam with 
 other modes. From the best information, 
 however, that I could obtain, I made cal- 
 
240 HEATING BY STEAM. 
 
 cxilatioiis on the supposition, that" the' 
 steam -was supplied from a large boiler, 
 
 and the rest employed for driving a steam- 
 
 engine, or for some other useful purpose. 
 On this principle then, it appeared, in 
 general, that open fires require consider¬ 
 ably more fuel to heat the same space, than 
 steam. Stoves, as commonly constructed 
 and used in our cotton-rnills, seem also to 
 require more fuel flian steam. With regard 
 to the improved stoves, -which are now 
 only begi nnin g to be used in some manu¬ 
 factories, 14o not know, that any accurate 
 comparison has yet been made. 
 
 207. In most manufactories, there is a 
 great many septate fires, which occasion, 
 in proportion to their number, not only a 
 loss of heat from thhfuel consumed, but 
 also of waste from inattention and care¬ 
 lessness; where steam, therefore, can be 
 used as a substitute for these, a great 
 saving, of fuel -will accrue. 
 
 208. Although in situations in which 
 there is a steam-engine, or a regular sup- 
 
HEATING BY.STEAM. ' 241 ' 
 
 ply of Steam kept up for other purposes, it 
 may be proper to use steam for warmiiig 
 
 buildings; yet,^ where that is not ths^ case, 
 
 unless a person can be appropriated to the 
 sole purpose of attending on the boiler, .1 
 would. hesitate to recommend it; for the 
 trouble and expense of attending on ,a 
 small boiler, on the common, construction, 
 and risk from carelessness of not keeping 
 up a regular heat, or of having it burst or 
 burnt out, would more than counterbal¬ 
 ance the advantage otherwise to be derived 
 from it. But I am much pleased to find 
 that ingenious mechanics are turning their 
 attention to the fitting up of boilers, so as 
 to require less attendance 
 
 209. Steam, however, has many material 
 advantages over every kind of stoves; niost 
 lands of stoves are more; or less liable to 
 injure the air, which comes in contact with 
 them, and to consume the dust. A dis¬ 
 agreeable oppressive smell is often pro¬ 
 duced, occasioned, probably, not only from 
 
 • See Mr. M'Naught’s Letter, Art. 180. 
 
 H h 
 
HEATING BY STEAM. 
 
 the combustion^ of the dust, but also from 
 the decomposition of the water suspended 
 in the atmospliere. The disadvantages of 
 throwing in a current of air, by heating 
 the external air, and combining ventilation 
 with heatiflg;^ have already been men¬ 
 tioned, (Art. 195,} and to these objections, 
 some of our most improved stoves are 
 liable. 
 
 All kinds of stoves are more or less 
 dangerous, and when constructed on the 
 principle of ventilation,.- they may become 
 particularly so, when the coakle or pan 
 cracks, or is burnt out. In that case, the 
 flames may find their way into the air- 
 flues, and so into the building. The 
 cdakles, in many situations, soon fail in 
 some part; in . which case, putting the 
 danger out of the question, they must 
 greatiy contaminate the air. It has been 
 supposed, that more cotton-mills have been 
 destroyed by fire, occasioned by stoves, 
 than from all other causes put together. 
 
 But steam being free from dust, and 
 the atmosphere uninjured by its heat, 
 
HEATING BY STEAM; 
 
 243 
 
 while it is much more cleanly and safe, it 
 must be more healthful-than any kind 
 
 of Stove. 
 
 Steam has ahother advantage over the 
 late improved stoves, that it can easily be 
 extended through buildings which are 
 widely-' spread, and nearly on the same 
 level; such, for instance, as are very com¬ 
 mon in calico printing vyorks: whereas 
 from the tendency which heated E^ir has to 
 ascend, it is exceedingly difficult to heat 
 places which are not considerably sibove 
 the level of the stove. 
 
 2i0. After considering the facts detailed 
 in this Essay, many other purposes than 
 those already mentioned, will suggest 
 themselves to readers, to. which heating by 
 steam may be usefully applied. It would 
 require a greater scope of knowledge, than 
 an individual could lay claim to, to point 
 them out To some purposes, however, 
 
 • It is worthy the consideration of those acquainted with nautical 
 affairs, how far it may be applicable in ships, particularly in men of 
 
HEATING BY STEAM. 
 
 244 
 
 there may be considerable obstacles; for 
 instance, it has been often proposed:for 
 - heating hot-houses; but a difficulty OCCUfS 
 here, of keeping up a regular heat during 
 the night, which could not, with a boiler 
 on the common construction, I believe, in 
 most cases, be done, without increasing the 
 expense of attendants. Were it not for 
 this objection, the heat from steam-pipes 
 appears to be more genial than that from 
 brick fines; and, in this case, perhaps a 
 boiler with a furnace similar to that der 
 scribed in Mr. M‘Naught’s letter, (Art. 
 180,) might be found to answer the pur¬ 
 pose, without any additional expense of 
 attendance.. 
 
 But in the . progress of improvement, 
 obst^les which at present exist to the use 
 of steam, may be removed. I have en¬ 
 deavoured plainly to state facts as they are 
 at-present, and ingenious men may draw 
 conclusions from them, which may contri¬ 
 bute to extend the useful application of 
 steam to many purposes, to which it is not 
 at present thought applicable. 
 
HEATING BY STEAM. 245 
 NOTES. 
 
 Note A. , . 
 
 Messrs. H. Houldsworth & Co. at their 
 old mill, Anderston, have a boiler equal to 
 that commonly used for a steam-engine of 
 twenty-one horse’s power. 
 
 But their engine has only the power of 
 sixteen horses j there is, therefore, a sur¬ 
 plus power of five horses in the boiler, and 
 this is appropriated to the warming of the 
 building; for which purpose it is found 
 quite sufficient. 
 
 The building consists of the mill in 
 front, and a house- behind, of the same 
 length as the mill; but not so large in its 
 other dimensions. 
 
 The mill contains 6 stories, each 116 
 feet long, by 27 feet 8 inches wide, by ,9 
 ' feet high, equal to 28,884 cubic feet. 
 Therefore, 28,884 cubic feet multiplied by 
 6 stories, is equal to 173,304 cubic feet in 
 
246 HEATING BY STEAM. 
 
 the mill. The back house contains 76,696 
 cubic feet; the whole is, therefore, 250,000 
 cubic feet Then 250,000 cubic feet, 
 dmded by five hotses, be equal to 50,000 
 cubic feet, the space which a boiler of one 
 horse’s.power will warm in a cotton-mill. 
 
 Now, reckoning that a horse^s power 
 occupies 25 cubic feet in a boiler, 50,000 
 cubic feet of space, divided by 25, is equal 
 to 2,000 cubic feet or space, which may be 
 warmed by 1 cubic fiaot of boiler. 
 
 It may be proper to observe, that this 
 allowance may be considered as perfectly 
 sufficient; for the thermometer in the mill 
 often stands above 80° of Fahrenheit 
 
 In the Linwood cotton-mill, (see Note 
 B,) for every cubic foot of boiler, 2,500 
 cubic feet of space were warmed up to 70 
 degrees of Fahrenheit, imder. the disad- 
 v^tages of a newly fitted up building, and 
 a large opening for the water-wheel. So 
 that ive may safely reckon upon a horse's power 
 as bang fully adequate to warm 50,000 cubic 
 
HJEATIKG BY STEAM. 24T 
 
 feet of space. Or^ what amounts to the same 
 thinly th^t one cubic foot, of boiler will warm 
 2,0PP cubic feet of Space. 
 
 Note B. . 
 
 General abstract relative to several Buildings 
 which have been warmed by Steam. 
 
 i’ll a 
 
 = 1 1 Jssasl 8 c| 
 
 Cubicfeetof 
 
 ed by X su¬ 
 perficial foot 
 of steam pipe 
 
 sssMI-lill i || 
 
 warmed 
 by 1.cubic 
 
 nil iiinii i II 
 
 Cubic 
 
 i§i 1 i=iiMr§ II 
 
 Cubic feet 
 
 building. 
 
 g gg j I go j " j 
 
 Substance of 
 which the 
 
 Cast-Iron, 
 
 Cast-Iron, 
 
 Cast-Iron, 
 
 not painted, 
 
 Cast-Iron. 
 
 Cast-Iron i 
 Cast-Iron, 
 Cast-Iron, 
 Cast-Iron, 
 Titi-Plate, 
 
 Tin-Plate 
 
 painted, 
 
 Cast-Iron, 
 
 Name of Mills. 
 
 ‘ 1 • • & ' . K . 
 
 S ', g . 1 g< " • M ~ 
 
 Is'i ■ % i: 
 
 1°p|- ' lai2|s' = ” J It 
 
 KS 1 , !I! S S3^1§ =S.=S I 2 2, 
 
 s S ' 1 ■s S 3 ® ^ J ' 
 
 in 
 
 g as o g 6£f2g (3 g| 
 
248 , HEATING BY STEAM. 
 
 , Note C. (see Art. 195.) 
 
 In June 1806, I made the following 
 experiments, in order to try the eflFect oh 
 the temperature of a room, by increasing 
 the current of air over the surface of steam- 
 pipes. 
 
 The room was 39 feet long, 22 feet , 
 wide, and 9 feet high. It contained a group of 
 ste^-pipes of tin-plate in a vertical posi¬ 
 tion, .fitted up and enclosed in a wooden 
 trunk, upon Mr. Roberton’s plan, (Art. 
 195). In order to increase the current of 
 air, a pair of fanners were made to suck it 
 out of the upper part of the trunk, and to 
 throw it into the room. The fanners 
 were 18 inches diameter, and 12 inches 
 wide, making 600 revolutions per minute. 
 
 Experiment 1st. 
 
 F. Therm. 
 
 External air _ 61° 
 
 Heat of room from steam-pipes, fan¬ 
 ners at rest - - - - 71° 
 
 Fanners half an hour in motion raised 
 the temperature to _ _ 76° 
 
HEATING BY STEAM. 249 
 
 After the fanners had been 20 min¬ 
 utes at rest, the temperature fell to 73” 
 The fanners were put in motion again 
 for 15 minutes, which raised the 
 temperature to r - - 76® 
 
 Thermometer held in the stream of 
 air issuing from the fanners, rose 
 to - - - - - 104” 
 
 , Observations^ 
 
 The temperature of the room before the 
 steam was admitted into the pipes, Was 
 omitted to be noted, but the difference 
 between the external temperature and that 
 of the room, was, at the beginning of the 
 experiment, 10°. The motion of the fan¬ 
 ners, increased the temperature 5” more. 
 
 Ewferment 2d, 
 
 F. Therm, 
 
 External air, - - - _ 63“ 
 
 Heat of the room before admitting ■ 
 the steam into the pipes, - 70 
 
 Steam in the pipes for an hour, but 
 the fanners at rest, raised the tem¬ 
 perature to - r - “ 74° 
 
 I i 
 
250 HEATING BY STEAM. 
 
 Fanneri in morioii for half an hour, 
 raised the temperature to - 76* 
 
 Thermometer held in the stream of 
 air issuing from the, fanners, rose 
 •to -- - - - - 125 
 
 Observations. 
 
 In experiment 2d, the temperature of 
 the room, previously to admitting the 
 steam into the pipes, was 7° higher than 
 the external air. The steam raised it in 
 an hour 4° more, and the fanners 2* 
 higher. 
 
 Hence the fanners appear to have in¬ 
 creased the effect of the steam-pipes one- 
 half, but it must be confessed, that it 
 would require a more extensive and ac¬ 
 curate set of experinients, in order to draw 
 satisfactory inferences. In the mean time, 
 however, I hope the above facts may not 
 be without their value. 
 
251 
 
 ADDITIONS AND GORRECTIONS. 
 
 Art. 14—25. I find, that some of our 
 most eminent chemists, are not yet con¬ 
 vinced of the accuracy of Mr. Dalton’s 
 speculations, with regard to the law of the 
 expansion of liquids, and its influence on 
 the construction of the thermometer j nor 
 are they disposed to admit the alteration 
 in the thermometric scale, which Mr. 
 Dalton proposes.. 
 
 Art. 58. Since this article was printed 
 off, I have had an opportuniy of reading 
 
 Speeches of H. Brougham, before, the 
 committee of the House of Commons, in 
 opposition to the gas-light and coke com¬ 
 pany.” Mr, Brougham there states many 
 curious and important facts, two ol which 
 it will; not be improper here to mention. 
 1st, T/iat Ax pounds of coal produces light 
 equal to one pou7id of tallow, 2d, That the 
 London Fire Company offered to insure 
 the works of Messrs. Philips & Lee, after 
 they were lighted by the coal gas, at one 
 half the former premium. 
 
252 ADDITIONS AND CORRECTIONS. 
 
 Art. 67. There has never, I believe, 
 been any very accurate comparison of Glas¬ 
 gow coal with that of Newcastle. Some 
 are of opinion, that it requires about double 
 the quantity of Glasgow coal to produce 
 the same heat as that of Newcastle. 
 
 Art. 68. From the nature of the thing, 
 culm must differ much in its effects in 
 producing heat. Therefore, we may ex¬ 
 pect some results very different from that 
 stated in this article. 
 
 Art. 154. It is a good method to make 
 the faucets with an inner part, no larger 
 in diameter than just to fit the spigot. This 
 supports the pipe, independently of the 
 cement, and prevents the risk of hurting 
 the joint from any external stress. This 
 iimer faucet is commonly made about two 
 inches deep, and has the spigot inserted 
 one inch into it. The practice of some, 
 is to make the outer faucet, or that which 
 contains the cement, six inches deep, for 
 all pipes above six inches diameter; and 
 to make the faucets of all pipes below six 
 
ADDITIONS AND CORRECTIONS. 253 
 
 inches, the same depth as the diameter of 
 
 the pipes. - 
 
 It is usual to make the . space for the 
 cement, all round the spigot, from f to x 
 an inch; that width is required, in order 
 that the cement may be firmly driven into 
 the joint. When the space is very nar¬ 
 row, this cannot be done. Qn the other- 
 hand, when too wide, there is a waste of 
 cement, and a risk of injury from unequal 
 expansion. 
 
 Page 63, line 22, for wood, charcoal, rcei/wood-charcoal. 
 
 -ns, la-' line,/cr Belidores Arch. Hydraulique, rrad Architec¬ 
 ture Hydraulique, par M- Belidore,'tom. iii. 
 
 -1S8, for Reaumeur, read Reaumur. 
 
 _174, line 4, 7, 9, and 11,/or facet rcaif faucet. 
 
 _17S, — 5 and 16, /or facet rrad faucet. 
 
 —^— 181, — 19, for the valve a, read the valve e. 
 
 —1— 182, — 4, 5, and 14, for guage-cock read gauge-cock. 
 
 -192, — 15,/ornewrMinext. 
 
 --223, — 23, for 112 read 212. 
 
I Jf lD E X. 
 
 Asductiok, 
 
 AddpH Cotton Mill, - 
 
 An-, ... 
 
 -breathed by the ho 
 
 speaes, ... 
 
 103 
 
 107 
 
 72 
 
 247 
 
 103 
 
 SO 
 
 Blowpipe, 
 Bodies, - 
 -colove 
 
 -their sp 
 
 Boerhaave, Dr. 
 
 Alcohol, - • - 
 
 Anderston tambouring mil4 
 Apparatus, feeding, - 
 
 129 
 
 131 
 
 232 
 
 129 
 
 123 
 
 133 
 
 247 
 
 235 
 
 114 
 
 187 
 
 -descripti 
 
 -for gene 
 
 Boiling, 
 
 10 
 
INDEX. 
 
 Cook, Douglas, & Co. - 247 
 " jpper and gold, expansion of, IGS 
 
 -pipe, - • - - , 200 
 
 -pipes, - - - 164 
 
 Chimnies, - - - . 9 
 
 Coakle and flues, - - 2C 
 
 Coakles, - -■ - - fl'l 
 
 Coal compared -with culm, - i 
 
 -gas, . . . 1£ 
 
 --Newcastle compared with 
 
 -Newcastle, - - .' 
 
 ipared with 
 
 i-mill, heating of, - 187 
 
 -itinwood, 246 
 
 Cotton-works, Milgavie, . - 192 
 Counting-houses & warehouses, 218 
 Crawford, Dr. relative to water 
 heated by charcoal, - 80 
 
 Cube root,- - - - ISO 
 
 , logarithmic, - 157 
 
 Cylindrical tin-plate canister, : 225 
 
 Coating, - 
 
 Coke, its proportion to 
 
 - 110 
 
 se] 
 
 - ISO 
 
 Condu 
 
INDEX. 
 
 -- ordinary, r - - 
 
 lishea existing in a hot spring. 
 
 Fossil coals charred, 
 Forfyce, Dr. ■* 
 Frying point. 
 
 - ‘^ percn 
 Fnel, - • 
 
 Garret for drying doth, 
 Gas, hydiogeneons, - 
 
 -its proportion to 
 
 Gold,^'’”’. - 
 
 Gun-powder, 
 
 — emitted hy tin-plate, 
 
 — expended, 
 
 — its expenditure, - 
 
 — means of measuring, 
 
 — of a coal-fire, - 
 
 — of its motion, 
 
 — red,- 
 
 wo much of, or too little, 237 
 Heating-mills, dwelling-houses, 
 id public buildings, ’ 
 
 -water for baths. 
 
 Hemp or cotton, stuffing of. 
 
 Hollow cit-iron l 
 [Hooke,,Dr. - 
 
 Horizontal cast-iron steam-ti 
 Hones’ power, ; - - 
 
 Hot-houses, heating,- - 
 Honldsworth & Hussie, Messr 
 Houldsworth, Messrs. & Co. 
 Honldsworth, Mr 
 
 an rollers 
 
 1S6 
 
 214 
 
INiJEX. 
 
INDEX. 
 
 Pag!. Page. 
 
 Ventilation in a drying stove, ib. Water, it! conversion into steam, S4' 
 
 — 231 -- its expansion, - 32 
 
 Vertical pipe, - 190 —^--warm, - 131 
 
 Vessels, cylindrical, - 111 Watt, Mr. . . 81 
 
 - - - 143 
 
 W -^-his first improvement 
 
 Warm baths at Helenshnrgh, 201 on the steam-engine, 141 
 
 Water, . . 77 -relative to steam, 79 
 
 - - - - 137 Wedgewood, Mr. - 154 
 
 -begins to boil, - 132 Wet goods, - - 21S 
 
A TREATISE 
 
 E€OJ¥<OMW OW W'UEE9 
 
 MANAGEMENT OF HEAT, 
 
 ipeating anu Dtging bg means; of ^team. 
 
 IN FOUR PARTS. 
 
 I. On the Effects of Heat, tlio Sleans of Measuring ih the Comparative 
 Quantity of Heat produced by different Kinds of Fuel, C-as-Light, &C. 
 —II. Qn Heating Mills, Dwelling-Houses, Baths, and Public Build¬ 
 ings.—III. On Drying and Heating by Steam.—IV. Miscellaneous 
 
 WITH MANY USEFUL TABLES. 
 ILLUSTRATED BY PLATES. 
 
 AFPEMBIX, 
 
 Observations on Chimney Fire-Places, pariicnlarly those used in Ireland 
 —On Stoves—On Gas-Lights—On Lime-Kilns—On Furnaces and 
 Chimneys used for Rapid DistiHiition in the Distilleries of Scotland- 
 On Improved Boilers for Evaporating Liquids. 
 
 By ROBERTSON BUCHANAN, 
 
 CIVIL ENGINEER. 
 
 GLASGOW: 
 
 I’nnted for the Author i 
 
PREFACE. 
 
 The favourable reception given by, the 
 public, to wi Essay on the Warming of Mills 
 and other Buildings by Steam, which I pub¬ 
 lished in 1807*, and the many additional 
 facts on the subject, which, since that 
 ppiod, have been determined, and the 
 farther, application of this agent to drying, 
 as well as heating, in various processes In 
 calico-printing and other manufactures, 
 have induced me to think of publishing 
 an enlarged edition of that Essay, and 
 ■to extend my plan to a, series of Essays on 
 .the Economy of Fuel and Management of 
 'Heat. 
 
 • For an account of. this Pamphlet, sec Philosophical jMagazini^ 
 ^idiolson’s Philosophical Journal, Monthly Magazine and various 
 •other periodical-publications for 1808. ■ 
 
iv , PEEFACE. 
 
 In order to clear the way for these prac¬ 
 tical inquiries, it seemed proper, to give 
 such a view of some of the principal laws 
 which regulate the phenomena of heat, as 
 woxdd, by the help of references, enable the 
 reader the better to imderstand the nature 
 of the facts and observations which would 
 occur in the subsequent parts of these in¬ 
 quiries. To this purpose, therefore, I have 
 devoted the first part of those Essays. • 
 
 Originally, I had no intention to make 
 this introductory part so large; but, in pur¬ 
 suing the subjects which it contains, it ap¬ 
 peared to me, that to embrace the objects 
 I had in view, it could not, with propriety, 
 be made less. It would, perhaps, not cofi- 
 duce to my credit as a writer, were I to 
 state what trouble this part cost ihe; and, 
 after all my labour, I fear it will be thought 
 by inany, a mere compilation. But, being 
 more anxious to make a useful than an ele¬ 
 gant book, I endeavoured, in a small com¬ 
 pass, to bring into view, all the practical 
 .knowledge that I could find on subjects, 
 which I thought might be beneficial to a 
 
PBEEACE. 
 
 V 
 
 valuable class of men, who (their, time 
 being otherwise fully occupied) have nei¬ 
 ther leisure, opportunity, nor inclination, 
 to search into numerous, and often costly 
 volumes. If I have succeeded in this in¬ 
 tention, my laboiu’ has not been in vain. 
 Nor win general readers, I trust, deem this 
 part altogether unworthy their notice. In 
 it will be found a concise view of the late 
 important discoveries made by Professor 
 Leslie and others, respecting heat. . . 
 
 The opportunities which I have had, of 
 conversing and corresponding with several 
 of those writers,' as well as with other men 
 of science, whose pursuits have been more 
 immediately practical, I have endeavoured 
 to turn to the advantage of the reader. 
 
 The superiority which this island enjoys 
 over other countries, from the abundance 
 of coal which it contains, is too well known 
 to require any eulogium. But in many 
 other respects, we labour under much dis¬ 
 advantage, which should stimulate us to 
 cherish this superiority which we enjoy 
 
Vi PREFACE, 
 
 over the nations on the Continent of Eu¬ 
 rope. The economy of fuel becomes a 
 subject of increasing importance, from the 
 increasing price of . labour, which demands 
 every exertion to counteract its effects on 
 our co mm erce and manufactures. Every 
 attempt, therefore, to save fuel, merits at¬ 
 tention; and the subject opens a wide and 
 an important field for investigation. 
 
 It is not the saving only of fuel which 
 merits attention, but its safe, easy, and 
 healthful application to the various pur¬ 
 poses of life. 
 
 The destruction by fire, of the two largest 
 Theatres in the kingdom, has directed 
 much of the public attention to render¬ 
 ing buildings less subject to so dreadfid 
 a calamity. In this important respect, 
 no means of heating buildings has yet 
 been devised, so good as that by steam, 
 and, from its novelty, none is yet so par¬ 
 tially known or imderstood.; I was there¬ 
 fore, induced to make it the principal sub¬ 
 ject, of the Essay which was published in 
 the year 1810 . 
 
PREFACE.' Vii ' 
 
 It consisted of Three Parts, the first of 
 these I have already mentioned. The 
 Second Part relates to the application of 
 steam to the heating of buildings of various 
 descriptions, such as dwelling-houses, manu¬ 
 factories, and public buildings. The Third 
 Part treats of the application of this agent 
 to di'ying of goods, as well as to other 
 matters relative to heating. Its' excellent 
 effect, in preserving brilliancy of colour, in 
 drying goods, is there proved by strong 
 facts ;—a consideration of great importance 
 in many of our manufactures. 
 
 Since that Essay was written, heating,, as 
 well as drying by steam, has been greatly 
 extended, which has induced me to publish 
 the present Treatise; the first Three Parts 
 of which, are the same as those Avhich formed 
 the Essay published in 1810. The Fourik 
 Part contains three sections, which run-par- 
 aUel with those Three Parts, and contain 
 all the rdcent discoveries respecting the 
 phenomena of heat, and an account of soihe 
 important improvements in the application 
 of sfeanr to the heating of buildings, &c. 
 
PREFACE. 
 
 viii 
 
 An Appendix is added; the subjects of 
 which are of so much practical utility, that 
 no apology will be required, but for what 
 imperfection may be found in. the mode of 
 treating them. 
 
 . I_must crave the indulgence of the reader, 
 for whatever want of unity, or other imper- 
 feciioas, he may discover in this Treatise.: 
 I have to plead, that it was witten at many 
 different and distant intervals, occasioned 
 by interruptions feom professional engage¬ 
 ments, as well as from other and more 
 irksome causes, which it is unnecessary 
 to enumerate. 
 
 With regard to the subject of Heating 
 by Steam, I beg leave here farther to re¬ 
 peat the Preface to the Publication to which 
 allusion , is made at the beginning of this 
 Introduction. 
 
 “In a country hke Britain, where man¬ 
 ufactures are more generally collected and 
 combined in large establishments, than 
 dispersed through individual dw'ellings, 
 
PREFACE. IK 
 
 the production anddifFusion of the warmth 
 necessary for the health and comfort of 
 the workmen, as well as for the prosecu¬ 
 tion of the different processes, become 
 objects of the first national importance. 
 
 “ The very great expense of insurance, 
 arising from the combustible nature of the 
 materials of the cotton manufacture in par¬ 
 ticular; the great difficulty of retrieving the 
 injury resulting to a well-established busi¬ 
 ness from the accidental destruction of 
 machinery; and the frequent alarzns from 
 fire, in our powder-mills, arsenals, and 
 dock-yards, furnish the strongest economi¬ 
 cal, as well as political recommendations, 
 for the more general employment of steam 
 for the purpose of warming buildings. • 
 
 “ The very limited degree in which 
 steam has yet been applied to this pur¬ 
 pose, might surprise us, did we not recol¬ 
 lect, that the steam-engine itself, although 
 known, perhaps, even before the time of 
 the celebrated Marquis of Worcester, 
 has only, within a very few years, by the 
 b 
 
PREFACE. 
 
 ingenious improvements of Mr. Watt, 
 been extensively introduced. The fre¬ 
 quent and various use of steam, to which 
 Mr. Watt’s improvements have given 
 rise, in different departments of manufac¬ 
 ture, have furnished accidental results of 
 great value, which are frequently little 
 known to the merely scientific inquirer; 
 
 “ The observations- which the Author 
 has been enabled to make, on various con¬ 
 trivances throughout the kingdom, for 
 heating by steam, modified by his own 
 experience, have led him to believe, that 
 the following remarks on this important 
 subject, will not be altogether undeserving 
 the notice of the public. 
 
 “He, however, lays no claim to origi¬ 
 nality, nor does he pretend to give informa¬ 
 tion to men of science: his object is merely 
 to make such a collection of facts as may 
 be useful to those’who Avish to put in 
 practice the warming of buildings by 
 steam. - - 
 
PREPACK. 
 
 xi 
 
 “ In making this collection, he has been 
 much indebted to the assistance of some 
 friends; without the aid of whose ingenu¬ 
 ity and experience, his readers would have 
 had still more reason to lament its defic¬ 
 iency, 
 
 “ Those who are most qualified to esti¬ 
 mate the importance of such investigations, 
 can best appreciate their difficulty, and 
 will most readily and candidly pardon the 
 unavoidable imperfection of this attempt; 
 the chief object of which, is less to satisfy 
 curiosity, than to direct the attention of 
 the public to the farther prosecution of 
 an inquiry, not less curious than useful.” 
 
 I shall now proceed to give an account 
 of the origin and progress of this applica- . 
 tion of steam. 
 
 An Accowit of the Origin and Progress of the 
 
 Application of Steam, to the purpose of Heat- 
 
 . ing Buildings. 
 
 In the Philosophical Transactions for the 
 year 1745, Colonel William Cook suggests 
 
PREFACE. 
 
 xii 
 
 the idea of warming rooms by steam. But 
 it does not appear that he ever attempted 
 to reduce it to practice. And although 
 Count Rumford, in the third number of 
 the Journals of the Royal Institution, men¬ 
 tions, that “ this scheme has frequently 
 “ been put in practice with success, in this 
 “cmmtry, as well as on the Continent,” 
 I have not been able to learn, that any 
 thing of importance was done, previously 
 to the use of steam in warming cotton- 
 miUs*. 
 
 It is natural to suppose, that Mr. Watt’s 
 attention to other applications of steam, 
 would lead him to the consideration of the 
 particular subject of heating buildings. 
 Such was indeed the - case. The period at 
 which he used steam for warming the 
 room in which he commonly wrote, was 
 1784, or 1785, probably the winter between 
 these two years. The room was about 18 
 feet long, by 14 feet wide, and 84 feet 
 , high; and the apparatus consisted of a 
 
 • A patent for heating by steam, was granted to John Hoyle, dated 7th 
 July, 1791; and another to Joseph Green, dated 9th December, 1793. 
 
PREFACE. 
 
 xiii 
 
 box, or heater, made of two side-plates of 
 tinned iron, about feet long, by wide, - 
 kept at the distance of an inch asunder, by 
 nieans of stays, and joined round the edges 
 by other tin-plates. This box was placed 
 upon its edge, near the floor of the room, 
 and furnished with a cock to let out the 
 air, and with a pipe, proceeding from its 
 lower edge to a boiler, in an under apart¬ 
 ment, which pipe served to convey the 
 steam, and return the water. The eflTect 
 produced by this apparatus, was less than 
 Mr. l¥att had calculated, which, perhaps, 
 may now be explained by Professor Leslie’s 
 experiments on the heat transmitted by 
 polished surfaces. 
 
 Mr. Boulton heated a room in his man¬ 
 ufactory by steam, soon after this; but 
 the very infirm state of his health at this 
 moment, prevents me from obtaining ac¬ 
 curate information concerning it*. He, 
 however, heated his bath by steam, a few 
 years later, I believe about the year 1789, 
 which he continued to do from that period, 
 until very lately. 
 
 
 Tilten previously to Mr. Boulton’s death. 
 
Xiv PREFACE. 
 
 Towards the end of the year 1794, he 
 assisted the late Marquis of Lansdown, to 
 improve an apparatus, erected by a Mr. 
 Green, for warming his library, by means 
 of air heated by steam; but the use of it 
 was afterwards abandoned, owing, I believe, 
 to some defect in the pipes or joints. 
 About a twelvemonth later, in the winter 
 of 1795, -6, Mr. Boulton directed the erec¬ 
 tion of a similar apparatus, for his friend 
 Br. Withering’s library, which, in point 
 of heating, answered perfectly; but the 
 pipes being made of copper, and soft sol¬ 
 dered in some places, the smeU of the 
 solder was rather unpleasant to the Doctor, 
 who was then in an infirm state of health 
 with diseased lungs. The apparatus was, 
 in consequence, removed to Soho, where 
 hlr. Boulton proposed erecting it in . his 
 own house, in which he was making al¬ 
 terations about this time; and he intended 
 to heat every room in the house by steam. 
 A boiler was put up for that purpose, in 
 one of the cellars; but some circumstances 
 occurred which prevented his continuing 
 the plan. The subject, however, under- 
 
PEEFACE. 
 
 .XV, 
 
 went frequent discussions; and the dif¬ 
 ferent modes t>f effecting it were amply 
 considered by Messrs. Boulton and Watt, 
 as was known to many of their friends, no 
 secret having been made, either of calcula¬ 
 tions of surface, or of the modes of apply¬ 
 ing them. 
 
 About the end of the year 1799, IMi-. 
 Lee. of Manchester, having a large increase 
 of his cotton-mill in view, consulted with 
 Messrs. Boulton and Watt, relative to the 
 best mode of heating it by steam ; and, in 
 the course of the subsequent year, he 
 erected his present apparatus of cast-iron 
 pipes, acting also as supports to the floor., 
 which answered perfectly; and was, both 
 in point of the materials used, and of the 
 construction adopted, as far as I know, the 
 first of the kind. From that period, many 
 apparatus were' constructed by them, in 
 some of which, applied to old buildings, 
 the pipes were conducted horizontally 
 through the rooms, with other variations 
 of little importance. 
 
PREFACE. 
 
 It may not be improper here to add, that 
 the vats, &c. of the dye-house of Messrs. 
 Wormauld & Gott, of Leeds, were heated 
 by steam, under the direction of Messrs. 
 Boulton and Watt. The apparatus was 
 planned in August, 1799, and set to work 
 either in the course of that, or early in the 
 following year. The history of that es¬ 
 tablishment has been very incorrectly given 
 in the Journals of the Royal Institution, 
 for 1801. 
 
 The merit of the first application of 
 steam, to the heating of buildings in Scot¬ 
 land, belongs to Mr. Snodgrass. He in¬ 
 troduced it* into the cotton-work, which 
 Messrs. Dale & M'Intosh established on 
 the banks of the Spey f. 
 
 Soon after this period, Mr. Hoiildsworth 
 of Glasgow, used it with great success. 
 His example Kas been followed by several 
 other respectable cotton-spinners. 
 
 • Li&e year 1799, and, there is reason to think, vitliout tlie know¬ 
 ledge of-what bad been done in England. 
 
 t See Philosophical Magazine, for Jlarch, 1S07. 
 
PREFACE. 
 
 XVll 
 
 Steam was soon afteiwards applied to 
 warm buildings, appropriated to the pur¬ 
 poses of calico-printing. Mr. Richard 
 Gillespie, in his calico-works at Anderston, 
 was induced, very early, to use it in his 
 warehouse for finished goods; and he has 
 since been gradually extending it through 
 other parts of his works*. It was also 
 soon adopted by calico-printers in En¬ 
 gland and Ireland. Its use for various pur¬ 
 poses, is now daily extending in every part 
 of the United Kingdoms. 
 
 * In the Introduction to the Tliird Part of this Treatise, there is a nar¬ 
 rative respecting the application of steam to the pilose of drying- 
 
TABLE OF CONTENTS. 
 
 PAGE 
 
 Prepace,._ ; 
 
 Account of the Origin and Progress of the Application 
 of Steam to the Heating of Buildings, - - xi 
 
 PART FIRST.—Effects of Heat—Means of Measuring 
 
 it—Fuel, die..1 
 
 Section I—Of Heat,.1—3 
 
 Of Thermometers,.5 
 
 Table, -.20 
 
 Expianation of the Table,.2l 
 
 Table of degrees of Thermometers, - . - 25 
 
 Section II.—Of Expansion, - - - - 31 
 
 Table of Expansions,.38 
 
 Liquids,.40 
 
 Section III.—On th.-' Specific Heat of Bodies, - - 41 
 
 Table of Specific Pleats, . 45 
 
 Gases, ib. 
 
 Liquids, ib. 
 
 Solids,.- 46 
 
 Remarks on tlie Table,'.47 
 
 Table of Specific Heats of Elastic Fluids, - - 49 
 
 Section IVb—Of Combustion, - - - - 56 
 
 Fuel,.59 
 
 Section V.—Of the Motion of Heat, - - - 85 
 
 Bodies,.89 
 
 Equal Bulks, -.90 
 
 Equal Weights,.ib. 
 
 Refrigeration of bodies in various kinds of Elastic Fluids, 128 
 Section VI.—Boiling, or Ebuliition, - - - 131 
 
 Of Steam, or Vapour,., 139 
 
 Table of the Force of Steam, &c. . - . . 147 
 
 Table of the Expansion of Air, .... 148 
 
 Table of the Expansion of Liquids, ... 149 
 
 Table of the Expar siou of Water, . . . ib. 
 
 Section VII_Of Ignition,.150 
 
 Description of Plate 1st,.158 
 
 PART SECOND_Heating Mills, Dwelling-Houses, 
 
 and Public Buildings, by Steam, ... Jgg 
 
 Section I_Of the Proportionate Sire of Boilers, 160 
 
 Section II.—Of the Proportion of Steam-Pipe rer 
 quired to heat a given space, .... jgg 
 
 Section HI.—Of the Substance and Surface .of the. 
 
 Steam "Pipe,.- 164 
 
 Section IV_General Observations respecting the Di¬ 
 rection and Arrangement of the Pipes, ■ ' - 168 
 
XX TABLE OF CONTENTS. 
 
 Section V.—Of the Method of connecting the Steam- 
 
 Pipes, .- 173 
 
 Section _Description of BoUer for generating 
 
 Steam, Ac..179 
 
 Apparatus for supplying Water, - - . . ib. 
 
 Apparatus for regulating the Damper, - - 180 
 
 Safety Valves,.181 
 
 Gauge-Cocks,.182 
 
 Contrivance to give Alarm, &c. - - - - ib. 
 
 Section MI_Syphons,.ISi 
 
 Section MIL—Description of some Cases of the 
 Direction and Arrangeraenr of Steam-Pipes in ac¬ 
 tual use, .187 
 
 Dwelling-Houses, - 194 
 
 Baths,.201 
 
 General Explanation of Plate 2d, ... 202 
 
 PART THIRD.—Drying and heating by Steam, - 203 
 
 Introduction,.ib. 
 
 Section I..210 
 
 Section II.—Of the Difference of Temperature, &c. 221 
 
 Table of the State of the Thermometer, &-c. - - 222 
 
 Section HI.—Of the Proportion between the Surface 
 of Steam-Pipe, and the Heat produced, - - 223 
 
 Table showing the Heat, Ac. 229 
 
 Section IV.—Miscellaneous Observations, - 230 
 
 Note A,.245 
 
 Note B.—General Abstract relative to several Buildings 
 which have been warmed by Steam, - - 247 
 
 Note C,.248 
 
 P.CRT FOURTH.—Miscellaneous Observations, 251 
 
 Section I.—On the Phenomena of Heat, &c. - ib. 
 
 Specific Heat of the Gases, compared with that of Water 
 and with different Solids and Liquids, - - 269 
 
 Section II.—On the Heating of Mills, Dwelling-Houses, 
 Baths, and Public Buildings, by Steam, - - 275 
 
 Methods of connecting Steam-Pipes, . - . 284 
 
 Section HI.—On Heating and Drying by Steam, 305 
 
 .APPENDIX.—Miscellaneous Observations on Chimney 
 Fire-Places, particularly those used in Ireland, - 307 
 
 On Stoves,..319 
 
 Operation of the Stove,.332 
 
 Account of the Lime -Kilns at Closcburn, Dumfrics-shire, 338 
 
 Gas-Lights,.346 
 
 On the' Furnaces and Chimneys used for Rapid Distilla¬ 
 tion, in the Distilleries in Scotland, - - - 356 
 

 MISCELLANEOUS 
 
 OM8EMr^4TIONB 
 
 ON THE PHENOMENA OF HEAT,-ON THE HEATING 
 
 OF MILLS, DWELLING HOUSES, BATHS, AND 
 
 PUBLIC BUILDINGS, BT STEAM.-ON DEYING 
 
 AND HEATING,BY STEAM, &C. 
 
 SECTION I. 
 
 On the Phenomena of Heat, 
 
 211, A-BOUT five years have elapsed since 
 the foregoing Parts of this Treatise vvere 
 written. During that period, many im¬ 
 provements of a practical nature on the 
 manner of heating Buildings, &c. by Steam, 
 have been made, of which notice shall be 
 afterward taken; but in regard to dis¬ 
 coveries respecting the laws xchich regulate 
 
252 PHENOMENA OF HEAT. ' 
 
 the ‘phenomena of heat I am not aware that 
 there is much new information to communi¬ 
 cate. In the Philosophical Transactions for 
 1812, is inserted an account of Mr. Brodie’s 
 
 fiirther experiments and observations on 
 the generation of Animal Heat f. “ The 
 near coincidence in the result of these ex¬ 
 periments is sufficient to prove, that we are 
 not yet in possession of a perfect theory of 
 the production of animal temperature; nor 
 do we see any objection to the inference of 
 Mr. B.that the temperature of warm-blooded 
 animals is considerably under the influence 
 of the nervous system. That the function 
 of respiration is one of the sources of animal 
 heat, cunnotbe doubted; perhaps it is. the 
 
 * See p. 1. 
 
 f « There is a very interesting paper in tlie Philosophical Transactions 
 (1792, voL 82. p. 199) by Dr. Currie, of Liverpool, on the changes in 
 animal heat occasioned by immersion in cold salt, and fresh water, and 
 by passing repeatedly from the water into air and vice i^ersa. These experi¬ 
 ments have not yet received any attention from chemists and physiologists. 
 They appear to me to subvert every theory of animal heat hitlierto pro¬ 
 posed, not even excepting the theory of Dr. Cla^vfo^d, ingenious and 
 plaiirible as it is. Some very curious experiments by Mr. Brodie, pub¬ 
 lished in the Transactions for 1811, arc equally incompatible with tlic 
 present diemical theory of respirarion. But there is an apparent discor¬ 
 dance between them and Uiose of Dr. Currie, whiclr ought to be cleared 
 up before any attempts can be made to construct a new theory of animal 
 heat.”— Thosison’s Hisiort of the Royal Society, Notc^ p. 129. 
 
THENOMENA OF HEAT. 253 
 
 primary one, since it prepares the blood for, 
 the various important purposes to which it 
 is subseiwient in the animal economy; but^ 
 as the evolution of heat is an almost con¬ 
 stant effect of chemical action, it is reason¬ 
 able to presume, from analogy, that the 
 various secretions which are constantly 
 going forwards, contribute, in no trifling 
 degree, to maintain the temperature of the 
 animal. We are, at present, veiy far from 
 being able to form any tolerable estimate 
 of the influence of each taken singly; but, 
 as our means of doing this shall increase, 
 we may expect to make a nearer approx¬ 
 imation to a just theory of this most inter¬ 
 esting part of physiology 
 
 212. In the year 1813, Leslie pub¬ 
 lished a volume, entitled “ A View of the 
 Facts ascertained concerning Heat, and its 
 relations with Air and Moisture.” 
 
 “ The object of this short Treatise (to 
 use the Author’s own words) is to convey, 
 in a popular form, a distinct though general 
 
 ^ See Eclectic Ketiew, December, 1814. p. 603, 60-J. 
 
254 PHENOMENA OF HEAT, 
 
 conception of the modern doctrine of Heat, 
 disengaged, as inuch as possible, from all 
 hypothetical reasonings. It will trace the 
 progress of experiment, from tlie earlifil* 
 times to the recent discovery of the arti¬ 
 ficial production and conservation of ex¬ 
 treme cold.” 
 
 213. In the Journal de Physique is given 
 A Memoir on the Heat of the Surfaces of 
 Bodies, hy M. Ruhland, of Munich. His 
 experiments, though curious, are not so 
 clear and decisive as to merit insertion m a 
 practical work. A few extracts, of a prac¬ 
 tical nature, from ]\Ir. Leslie’s publication 
 above alluded to, will doubtless be accept¬ 
 able to those readers who may not have 
 access to the works of that celebrated 
 Philosopher. 
 
 214. “ The increased capacity of rarefied 
 • air is the true cause of the cold which pre¬ 
 vails in the higher regions of the atmo¬ 
 sphere*. 
 
 * Leslie, p. II. 
 
PHENOMENA OF HEAT. 255 
 
 215. “ That temperature is hence inverse¬ 
 ly as the capacity of air possessing the rarity 
 due to the given altitude. Having therefore 
 ascertained, hy some delicate experiments, 
 the law which connects the capacity with 
 the rarity of air, it was not very difficult 
 to trace the gradations of cold in the higher 
 atmosphere, and even to mark the precise 
 limit where the reign of peipetual congela¬ 
 tion must commence. Thus, I find that, 
 under the equator, the boundary of the 
 frozen region begins at the altitude of 15207 
 feet, in the parallel of 45° at 7671 feet, in 
 the latitude of London at 5950, and in that 
 of Stockholm at 3818, while towards the 
 pole it comes to graze along the surface 
 
 ■ 216. “ A new principle appears to com¬ 
 bine its influence, and the rate of dispersion, 
 in aeriform media, is found to depend chiefly 
 on the nature of the mere heated surface. 
 From a polished metallic surface, heat is 
 feebly emitted; but, from a surface of 
 glass, or stiU better from one of paper, it is 
 discharged with profusion. If two equal 
 
 
PHENOMENA OP HEAT. 
 
 256 
 
 balls of thin bright silver, one of them en-, 
 tirely uncovered, and the other sheathed 
 in a case of cambric, be filled with water 
 slightly warmed, and then suspended in a 
 close room, the former wiU lose only 11 
 parts of its heat in the same time that the 
 latter will dissipate 20 parts. Of this ex¬ 
 penditure, 10 parts from each of the balls 
 is communicated in the ordinary way, by the 
 slow recession of the proximate particles of 
 air, as they come to be successively heated. 
 
 The rest of the heat, consisting of 1 part 
 
 from the naked matallic surface, and of 10 
 parts fi.-om the. cased surface, is propagated 
 through the same meclium, but with a cer¬ 
 tain diffusive rapidity, which, in a moment, 
 shoots its influence to a distance, after a 
 mode entirely peculiai; to the gaseous fluids. 
 The very superior propellent energy of a 
 surface of glass or paper in comparison of 
 that of a metallic one, lyes within the com¬ 
 pass even of ordinary observation. If a 
 glass caraffe or a pot of porcelain be filled 
 with boilidg water, on bringing towards it 
 the palm of the hand, an agreeable warmth 
 will be felt at the distance of an inch or two 
 
PHENOMENA OP HEAT. ,257 
 
 from the heated surface; but if a silver pot 
 be heated in the same way, scarcely any 
 heat is at all perceptible on approaching 
 the surface, till the fingers have almost 
 touched the metal itself. 
 
 217. “ It is curious to inquire how such 
 a singular diversity can arise. If the silver 
 ball be covered with the thinnest film of 
 gold-beater’s skin, and which exceeds not 
 the 3000th part of an inch in thickness, 
 
 the power of dispersioii will be augmented 
 
 from 1 to 7; if another pellicle be added, 
 there will be a farther increase of this 
 power, from 7 to 9; and so repeatedly 
 growing, till after the application of five 
 coats, when the propellent energy will reach 
 its extreme limit, or the measure of 10. 
 In this case, the metallic surface is precluded 
 from all contact with the air, and it must, 
 therefore, act in consequence of its mere 
 approximation to the external boundary. 
 We may thence infer, that air never coines 
 into actual contact with any surface, but 
 approaches much nearer to glass or paper 
 than to polished metal, from which it is 
 
258 PHENOMENA OP HEAT, 
 
 separated by an interval of at least the 
 500th part of an inch. A vitreous surface, 
 firom its closer proximity to the recipient 
 medium, must hence impart its heat more 
 copiously and energetically, than a surface 
 of metal in the same condition; and the 
 mei:al, to a certain extent, can act in re¬ 
 ducing the power of the other. When a 
 pellicle was applied, the metallic surface 
 immediately under it repelled partially the 
 atmospheric boundaiy, and reduced the 
 darting efflux of heat from 10, which would 
 have been thrown by the skin alone, to 
 about 7, or only 6 more than the efficacy 
 of the naked metal. The repelling influence 
 of the-' metallic plate was sensible even 
 imder four coats, or at the distance, of the 
 750th part-of an inch horn the external 
 
 218. “ The very singular and unexpected 
 facts now detailed merit attention, and sug¬ 
 gest a variety of improvements in the prac¬ 
 tical management of heat. A vessel with a 
 bright metallic surface is the best fitted to 
 
 • Leslie, p. 18—21. 
 
PHENOMENA OF HEAT. 259 
 
 preserve liquors either long warm, or as a 
 conservatory to keep them cool. A silver 
 pot will emit scarcely half as much heat 
 as one of porcelain; and even the very 
 slightest varnishing of gold, platina, or 
 silver, which communicates to the ware a 
 certain metallic gloss, renders this new 
 kind of manufacture about one-third part 
 more retentive of heat. The addition of 
 a covering of flannel, though indeed a slow 
 conductor, far from checking the dissipa¬ 
 tion of heat, has directly the contrary 
 tendency; for it presents to the atmo¬ 
 sphere a surface of much greater propulsive 
 energy, which it would require a thickness 
 of not fewer than three folds of this loose 
 substance fully to counterbalance. The 
 cylinder of the steam-engine has lately 
 been most advantageously sheathed with 
 polished copper. 
 
 219. “ The progress of cooling is yet more 
 retarded, by surrounding the heated vessel 
 on all sides, at the distance of near an inch, 
 with a case of planished tin; and the ad¬ 
 dition of other cases, following at like in- 
 
 K k • 
 
260 PHENOMENA OF ffiEAT. 
 
 tervals, augments continually the effect. 
 With an obstruction of one case, the rate 
 of-refrigeration is 3 times slower, mth two 
 cases it is 5 times slower, with three cases 
 it is 7 times slower, and so forth; as; exr 
 pressed by the succession of the odd num¬ 
 bers. By multiplying the metallic cases, 
 therefore, and disposing them, like a nest, 
 at regular intervals, the innermost could be 
 made to retaia the same temperature, with 
 little variation, for many hours, or even days. 
 Such an apparatus would obviously be well 
 calculated for various culinary and domestic 
 purposes., 
 
 220. “ In the conveyance of heat by 
 means of steam, the surface of the conduct¬ 
 ing tubes should have a metallic lustre. 
 On the contrary, if it, be intended by that 
 mode to warm an apartment, they should 
 be coated on the outside with soft paint, 
 to facilitate their discharge of heat. For 
 the same reason, metallic pots are more 
 easdy heated on the fire, after their bottoms 
 have become tarnished or smoked. If a 
 bright surface of metal be slightly furrowed 
 
PHENOMENA OF HEAT. . 261 
 
 or divided by fine flutings, it will emit 
 heat sensibly faster, because the prominent 
 ridges, thus brought closer to the general 
 atmospheric boundary, will excite the pul¬ 
 sations with augmented energy. 
 
 221. “ On the other'hand, a plate of metal, 
 however thin, if only burnished on each 
 side, will form the most efficacious screen. 
 A smooth sheet of pasteboard, gilt over both 
 sides, would answer the same purpose. But 
 a complete and elegant screen might be 
 composed of two parallel sheets of China 
 papei’, placed about an inch asunder, and 
 having their inner surfaces gilt, and their 
 outsides sprinkled with flowers of gold and 
 silver. 
 
 222. “ Since, in a still atmosphere, the 
 momentary flow of heat from any vessel, 
 whatever this may contain, depends merely 
 on the condition of its surface, the whole 
 accumulated discharge, during similar de¬ 
 scents of temperature, is evidently propor¬ 
 tional to the time elapsed. Hence, a very 
 simple and accurate method is suggested, 
 
262 PHENOMENA OF HEAT. 
 
 for ascertaining the capacity of different 
 liquids, or their specific attraction to heat. 
 Into a glass ball, two or more inches in 
 diameter, and blown extremely thin, with 
 a narrow short neck, and having a delicate 
 thermometer inserted through it, the liquid 
 to be examined, which had been previously 
 warmed a few degrees, is carefully intro¬ 
 duced by means of a funnel. The ball is 
 then made to rest against the tapering 
 points of three slender glass rods at the 
 height of several niches above the table, 
 and sheltered &om any irregular agitation 
 of the air of the apartment by a large re¬ 
 ceiver passed over it. The number of 
 seconds which the thermometer now takes 
 to sink firom one given point to another, 
 or to the middle of its distance from the 
 limiting temperature, is noted by help of 
 a stop-watch; and the ball being thoroughly 
 emptied and again successively filled with 
 other liquids, the like obsen^ations are re¬ 
 peated. Tliese several, intervals of time, 
 allowing a slight correction for the matter 
 of the shell itself and of the inserted bulb 
 of the thermometer, will consequently ex- 
 
PHENOMENA OP HEAT. 263 
 
 press the proportional quantities of heat 
 contained in equal bulks of the successive 
 liquids. But their densities being already- 
 known, it is hence easy to conapute their 
 respective capacities, or the quantities of 
 heat which equal weights of them are cap¬ 
 able of containing. * By a process grounded 
 on the same principles, the capacity of a 
 solid, when broken or reduced to a gross 
 powder, may be determined*.” 
 
 223. “ In the regulating of many processes 
 of art, and in directing the purchase and 
 selection of various articles of produce, the 
 application of the hygrometer would render 
 material service. Most warehouses, for in¬ 
 stance, require to be kept at a certain point 
 of dryness, and which is higher or lower 
 according to the purposes for which they 
 are designed. The printing of linen and 
 cotton is carried on in very dry rooms; but 
 the operations of spinning and weaving 
 succeed best in air which rather inclines, to 
 dampness. The manufacturer is at present 
 entirely guided by observing the effects 
 
 Leslie, p. 26—31. 
 
264 PHENOMENA OF HEAT, 
 
 produced, and hence the goods are often 
 shriveled, or.otherwise injured, before he 
 can discover any alteration in the state of 
 the medium. But were an hygrometer, 
 even of the most ordinary construction, 
 placed in the room, it would exhibit every 
 successive change in the condition of thle 
 air, and immediately suggest the proper 
 correctiofli The same means could be em¬ 
 ployed most beneficially, in attempering the 
 atmosphere of public hospitals. 
 
 224. “ That wool and corn have their 
 weight considerably augmented by the pre¬ 
 sence of moisture, is a fact well known. 
 Without supposing that any fi-audulent 
 practices are used, this difference, owing 
 merely to the -variable state of the air in 
 which the substances are kept, may yet in 
 extreme cases amount to 10 or even 15 
 per cent. Grain or paper preserved in a 
 damp place, will be found to swell nearly 
 after the same proportion. But the real 
 condition of such commodities might easily 
 be detected, by placing the hygrometer 
 within a small wired cage, and heaping 
 
PHENOMENA OP HEAT. ,265. 
 
 overithiss fora few. minutes, aqxiantity of 
 the wool or grain which is to be examiued*. 
 
 225. ‘^ The application of heat constant¬ 
 ly increases the dryness of the air, or 
 its disposition to dissolve moisture. This 
 propGlty is so generally known, that the 
 evaporating power of the medium is very 
 seldom in . practice referred to any other 
 cause. Drying houses, for example, are 
 commonly constructed as if heat were to 
 produce the whole effect; no means being 
 emplo^'ed for aiding the escape of the air, 
 after it has become charged with humidity, 
 and consequently rendered unfit for per-* 
 forming any longer the process of evapora¬ 
 tion. 
 
 226. “ The influence of warmth in aug¬ 
 menting the dryness of the air, or its dis¬ 
 position to imbibe moisture, explains most 
 easily a singular fact remarked by some 
 accurate, observers. If two equal surfaces 
 of water be exposed in the same situation, 
 the one in a shallow; and the other in a 
 
 » Leslie, p. 92—94. 
 
266 PHENOMENA OF HEAT, 
 
 deep vessel of metal or porcelain; tlie latter 
 is always found, after a certain interval of 
 time, to have sufiered, contrary to what we 
 might expect, more waste by evaporation 
 than the former. This observation was 
 once made the ground, of a very absurd 
 theory, although the real explication of it 
 appears abundantly simple. Amidst all 
 the changes that happen in the condition 
 of the ambient medium, the shallow pan 
 must necessarily receive more completely 
 than the deeper vessel, the chilling impres¬ 
 sions of evaporation, since it exposes a 
 smaller extent of dry surface to be partly 
 heated up again by the contact of the air. 
 The larger mass being, therefore, kept in¬ 
 variably warmer than the other, must in 
 consequence support a more copious ex- 
 
 227. Professor Leslie’s new and very 
 curious application of producing cold by 
 evaporation, consists, in placing under the 
 receiver of an air-pump, two vessels, one 
 containing a considerable quantity of con-, 
 
PHENOMENA OF HEAT. 267 
 
 centrated sulphuric acid, or of muriate of 
 lime, or of any other substance which ab¬ 
 sorbs moisture from the air, and the other 
 vessel holiiing a small portion of water. 
 As soon as the receiver is e’iJiausted, the 
 water begins to boil, though at a common 
 temperature, and when a pretty good va¬ 
 cuum is made, the pumping may be stop¬ 
 ped, and after a while, the water becomes 
 entirely frozen. For this experiment to 
 succeed, the surface of the substance that 
 absorbs the aqueous vapour, should be con¬ 
 siderable, and concentrated sulphuric acid 
 is preferred by Mr. Leslie to any other 
 absorbent of moisture. Tire water to be 
 frozen, must be in small quantity, and con¬ 
 tained in a thin metallic dish*. 
 
 For further information on the subjects 
 of Mr. Leslie’s inquiries, I beg leave to 
 refer to the work itself. 
 
 In the “ Annales de Chimie ” for Jan. 
 1813, vol. Ixxxv, is a “ Memoir on the 
 Determination of the Specific Heat of the 
 
 * Aikin’a Chemical Dictionary, Supplement, p. 97. 
 
PHENOMENA OF HEAT. 
 
 different G^es. By MM. F. Delaroche, 
 M. D. and E. Berard.” “ This memoir 
 {says Dr. Thomson in his Annals of Philos¬ 
 ophy) gained the prize proposed by the 
 Institute, and deserves particular attention. 
 It overturns the theory of animal heat ad¬ 
 vanced by Crawford, and Lavoisier’s theory 
 of combustion.” 
 
 From this long paper, I shall make the 
 following short extracts, being the only parts 
 of it which fall under my plan. 
 
 228. “ The difficulty of this sort of ex¬ 
 periments has prevented us from determin¬ 
 ing if the change in the capacity for heat 
 by pressure be the same in all gases. This 
 is exceedingly probable, as the increase of 
 density of each from pressure is the same. 
 Hence the opinion ought to be admitted 
 till new experiments demonstrate to the 
 contrary. We have no direct proofs of it, 
 however. The very curious experiments 
 of M. de Saissy*, if they are exact, may 
 
 * M. de Saissy, a phUosopber of Lyons, has made, experiments, -firom. 
 
PHENOMENA OP HEAT. - 269 
 
 even induce us to entertain doubts on the 
 subject. 
 
 “ Specific Heat of the Gases, compared xvith 
 that of Water and with different Solids 
 and Liquids. 
 
 ;229. “ We cannot make experiments to 
 determine the specific heats of the gases 
 without remarking, that, when equal volumes 
 are considered, they are very small, com¬ 
 pared to the specific heats of liquid and 
 solid bodies. The most careless experi¬ 
 ment is sufficient to prove the justice of 
 this assertion, which a more exact exami^ 
 nation fully confirms. Thus, if we compare 
 the specific heat of an equal volume of 
 olefiant gas (which under the same volume 
 has the greatest specific heat) and of water, 
 we find that the first is only the two thou¬ 
 sandth part of the second. 
 
 230. “ If we take the same weight of 
 each, the specific heat of the gases ap¬ 
 proaches much more nearly to that of the 
 solid bodies, as may be seen from the re¬ 
 sult of our experiments, which we here lay 
 before our readers:— 
 
2T0 PHENOMENA.OF.HEAT. 
 
 . - Specific heat. 
 
 Water - - - - 
 
 - - 1.0000^ 
 
 Air. 
 
 - - 0.2669 
 
 Hydrogen - - - 
 
 - - 3,2936 
 
 Carbonic acid - - 
 
 - - 0.2210 
 
 Oxygen - - - 
 
 - - 0.2361 
 
 Azote - - - _ 
 
 - - 0.2754 
 
 Oxide of azote - 
 
 - - 0.2369 
 
 Olefiant gas - - 
 
 - - 0.4207 
 
 ' Carbonic oxide - 
 
 - - 0.2884 
 
 ' Vapour of water - 
 
 - - 0.8470 
 
 232. “ From this table it appears, that, 
 if we except hydrogen, which has the 
 greatest specific heat of all known bodies, 
 all the gases that we have examined have 
 a smaller specific heat than water, and a 
 greater specific heat than any of the metals. 
 
 233. “ The results which we have obtained 
 by comparing the specific heat of the gases 
 witli that of water, enable us to decide 
 whether, as some have thought, , it would 
 be. attended with a saving of fuel, to em¬ 
 ploy the action of dilated air,. instead of 
 steam, in steam-engines. We consider the 
 
■PHENOMENA.OF HEAT. 271 
 
 question here under a point of view entirely 
 theoretic, abstracting both the difficulty of 
 constructing. such machines, and the loss 
 of power, which could. not be entirely a- 
 voided. Setting out from the specific heats 
 of water and air contained in the preceding 
 table, we have found that with the same 
 quantity of heat employed in the one case 
 to convert water of 32° into steam, but 
 without raising its temperature higher than 
 212°, and in the other to bring the tem¬ 
 perature of atmospherical air from 32°,to 
 212°, the effects produced in the first case 
 would be to those produced in the second 
 case as 1 to 1.285: but the advantage in 
 favour of air would be much greater if the 
 temperature were raised still higher *.. It 
 is obvious, that, from the knowledge which 
 we already possess of the quantity of heat 
 given out by steam when it is condensed^ 
 and from the data furnished by ^our experi¬ 
 ments on the specific heats of the gases, it 
 
 * “ Thus, if instead of applying the same quantity of heat to raise a mass 
 of air from 32° to 212°, it was employed-to raise the temperature of §■ of 
 . it from 32° to 572°, tlie effect produced in this case would be 3.043, or 
 thrice as great as would be produced by employing the same quantity of 
 
was -very possible to arrive at the solution 
 of this question; hut the calculations being 
 somewhat complicated, and requiring, in 
 order to be presented with clearness, details 
 which might appear foreign to the subject 
 proposed by the Institute, we will not give 
 them here*.” 
 
 534 " It is necessary, therefore, unless 
 we deceive ourselves, to abandon the hy¬ 
 pothesis which ascribes the evolution of 
 heat in cases of combination to a diminution 
 of the'specific heat in the bodies combined, 
 and admit, with Black, Lavoisier, and 
 Laplace; and many other plulosophers, the 
 existence of caloric in a state of combination 
 in bodies. The knowledge of the specific 
 heat of oxygen alone would be sufiicient 
 to induce us to adopt this opinion: for it 
 is so small that it is almost impossible for 
 US to account for the great quantity of heat 
 disengaged during the combustion of the 
 greatest number of bodies, unless we sup¬ 
 pose that this heat previously existed in a 
 State of combination. Accordingly, wheii 
 
 * TJiomson’s Annals of Fhflosophy, p. 435, 436. 
 
PHENOMENA OF'HEAT, 273 
 
 the opposite hypothesis was adopted, philos- 
 opliers were obliged to suppose the specific 
 heat of this gas, fifteen times greater than 
 it is in reality. 
 
 235. “We must not supjpose, howeverj 
 that there exists no relation between the 
 specific heat of compounds and that of their 
 constituents. Too many facts prove this 
 relation to make it possible to deny it. 
 Water, in this respect, constitutes the great¬ 
 est deviation which has been observed; yet 
 it does not exceed one-third of the specific 
 heat of this fluid. In general, we may say 
 that the constituents of a body communi¬ 
 cate to it their specific heat. This is very 
 observable in the combinations of hydrogen, 
 which has the highest specific heat of aU 
 known bodies. The compounds which it 
 forms have a much greater specific-heat 
 than other bodies. Hence the great specific 
 heat of water, of olefiant gas, and of animal 
 and vegetable substances 
 
 236.1 find, that many of our most eminent 
 chemists, are not yet convinced of the ac- 
 
 » Thomson's Annals of Philosophy, p. 4-39. 
 
274 
 
 PHENOMENA OF HEAT. 
 
 curacy of Mr. Dalton’s speculations, with 
 
 regard to the law of the expansion of 
 liquids, and its influence on the construc¬ 
 tion of the thermometer (See Art. 14. 
 25;) nor are they disposed to admit the 
 alteration in the thermometric scale, which 
 Mr . Dalton proposes. Professor Playfair, 
 however, seems to agree with Mr. Dalton; 
 see'his “ Outlines of Natural Philosophy,” 
 vol. I. p. 223. 
 
 • Uie cold at Glasgow, in the t^ter of 1814, was very severe, but 
 
HEATING OF MILLS, &c. 275 
 
 SECTION 11. 
 
 ON THE HEATING OF MILLS, DWELLING-HOUSES, 
 
 BATHS,'AND PUBLIC BUILDINGS, BY STEAM. . 
 
 Chimneys. 
 
 237. In consequence of an act of Parlia¬ 
 ment, for regulating the height of chimneys 
 of steam engines, and other works in the 
 city and sub 'irbs of Glasgow, Messrs. Muir, 
 Brown, & C i. erected a chimney 108 feet 
 high, at their works. It is 3 feet square, 
 within, and the flues of their various boilers 
 are conveyed into it. ^^at they did, in 
 compliance with the act of Parliament, 
 merely with a view to prevent the un¬ 
 pleasant effects of smoke, they find a very 
 great saving of fuel, and (what is of equal 
 if not greater importance) also of time. 
 They now use cuhn instead of coal and 
 
 • ■ * Tliere has never, I believe, been any very accurate comparison of 
 Glasgow coal with tliat of Newcastle. Some are of opinion, that it re¬ 
 quires about double tlie quantity of Glasgow coal to produce tlie same heat 
 as that of Newcastle.' (See Art'67.) 
 
 From the nature of .die thing; culm must differ much in its effects in 
 producing heat Therefore, we may expect some results very different 
 from that stated in Xrticle '68. ' , 
 
 M m 
 
276 HEATING OF MILLS, &c. 
 
 tkey bring water, &c, to the boiling point 
 
 in mucli less time then formerly. 
 
 238. Messrs. Robert Mutrie & Co. have 
 with still greater advantage, erected a very 
 handsome chimney at their works, at Man¬ 
 chester. It is 120 feet high above ground, 
 3 feet square inside at top, and 11 feet 
 square inside at bottom. See Plate 3, fig. 1. 
 The strength of this chimney was put to a 
 severe trial, by a tremendous gale of wind 
 which took place in the month of December 
 last, (1814.) It was then newly finished, 
 and surrounded with the entire scaffolding, 
 thereby exposing a much greater surface to 
 the violence of the tempest; yet such is the 
 excellence of the principle of its construc¬ 
 tion, that it sustained not the smallest injury. 
 
 239. The advantage of liigh chimneys has 
 alsobeenfor a considerable time experienced 
 in Staffordshire, where they are built in the 
 form of cones, They are made very large 
 below, probably for the convenience of the 
 introduction of many flues into one chim¬ 
 ney, as well as for strength. The wideness 
 
BY STEAM. 
 
 211 
 
 bfilow IS of use also, la allowing room for 
 changing the current of the smoke, from a 
 horizontal, to a vertical direction, 
 
 240. The following observations on chim¬ 
 neys, furnaces, and boilers, by M. Chaptal, 
 appear to me worthy of the notice of the 
 reader. 
 
 241. “ The air of a chimney, dilated by 
 heat, may be considered as a lighter fluid 
 than atmospheric air^ and wliich must 
 necessarily rise with a rapidity proportionate 
 to the difference of gravity, so that a rapid 
 arid incessant current of external air through 
 the fire-place must be established, in order 
 to expel and occupy the place of that which 
 rises. 
 
 242. Hence it follows: 1. That the high¬ 
 er the chimney of a fuiuace is, so much the 
 stronger will be the draught, provided the 
 column of air can be heated and rarefied 
 throughout almost the whole length; for 
 otherwise, the circidation will only be im¬ 
 peded. 2. That the draught will be more 
 
278 HEATING OF MILLS, &c. 
 
 rapid, the thicker are the sides of the chim¬ 
 ney, or the worse conductors of heat are the 
 materials of which it is constructed; because 
 the heat being then retained within the 
 chimney, the column of external air is less 
 dilated by it, and consequently more dense, 
 and better adapted by its excess of weight to 
 expel the rarefied column in the chimney. 
 3. That the size of the chimney has no kind 
 of influence over the draught; and that, in 
 this respect, the dimensions should be de¬ 
 termined by the volume of the column of 
 air transmitted by the fire-place. 4. That 
 the draught of a chimney may be ascertained 
 by introducing an inflamed body into the 
 interior of ik^.” 
 
 243. On the height and construction of 
 chimneys. See. in the West Indies, see Ob¬ 
 servations and Advices for the improvement 
 of the Manufacture of Muscovado Sugar 
 arid Rum, Part L; by Bryan Higgins, M. D. 
 Printed, St. Jago De La Vega, Jamaica, 
 p. 59. 
 
 * Chaptal’s Chcmistiy, applied to Arts and Manufactures, p. 119, 120. 
 
BY STEAM. 
 
 279 
 
 Furnaces for Boilers. 
 
 244. “ The ash-pit should be wide, deep, 
 and protected from too rapid currents of 
 external aii’. It is separated from the fire¬ 
 place by a grate which supports the fuel, 
 the bars of which should be at such a dis¬ 
 tance, that the coal cannot, fall through, 
 but nevertheless not so close as to interrupt 
 the passage of the air. To judge of the 
 draught of the furnace, and to prevent the 
 grate from being choked, you may place 
 a basin full of water on the bottom of the 
 ash-pit; the vivid light of the grate reflected 
 in it shows, every moment, what points are 
 choked, on which you restore the draught, 
 by removing vfrthan iron poker, the matters 
 which obstructed it, and by raking out the 
 
 245. For such coal as is used in Glasgow 
 and its neighbourhood, a distance of about 
 five-eighths of an inch, between the grat¬ 
 ing bars, is foimd to answer well with large 
 coal, and a distance of about three-eighths 
 for culm. Bars of two feet in length, should 
 
 Chajtal’s Chemistry, applied to Arts and Manufactures, p. 142, 14S. 
 
280 HEATING OF MILLS, &c. 
 
 be about one-and-arhalf inches thicls on 
 their upper edge, and have their sides 
 parallel, for about one inch downward, so 
 as to preserve the same opening, after they 
 have been a considerable time in use, and 
 partly burned away. 
 
 246. In many of those manufactories 
 whereboders are used for dyeing, and similar 
 purposes, there is a great waste of fuel and 
 destruction of the furnace-doors, owing to 
 their being placed close to the end of the 
 furnace-bars. In this case, much heat is lost 
 by the doors becoming red hot. They are 
 by that means, soon put out of shape, and 
 no longer answer the purpose of excluding 
 the air. There ought always to be a con¬ 
 siderable space between the finnace-door 
 and the fire. ^Vheh this is done, the doors 
 continue to fit, and prevent air rushing be¬ 
 tween the fire and bottom of the boiler. 
 
 Boilers. 
 
 247. “ The form of boilers has always 
 appeared to me to be an object of little im¬ 
 portance, if the furnaces were but well con- 
 
BY-STEAM. 
 
 281 
 
 struGted. It is, nevertheless, true, that those 
 o£ a circular form are more easily heated 
 than the others, and that they are less liable 
 to injury. I should therefore prefer them 
 for the purposes of Evaporation only; but 
 when it is necessary to work by dipping 
 into the boiler, the manipidations'are ; ren¬ 
 dered more easy by the square form; 'con¬ 
 sequently the nature of the operations must 
 decide with" respect to the form to be 
 adopted. 
 
 248. “ The flat bottom of round boilers 
 has always appeared to me to be attended 
 with inconveniencies. 1. It is difiicult to 
 empty the bottom of a boiler which has 
 this form; 2. The impurities which often 
 sully the contents, and are deposited over 
 a large surface, remain exposed to, the tu^ 
 multuous action of the liquid; 3, The liquid 
 bears everywhere with its whole weight on 
 the bottom already weakened by the heat.: 
 
 249. “ By making, the bottom of boilers 
 to project inwards, so as to present a, con¬ 
 cave surface externally, all these defects 
 
282 HEATING OF MILLS, &C. 
 may be corrected, and other advantages 
 procured- 1. The fire is applied in a more 
 equal maimer to eveiy point, firom this cir¬ 
 cumstance alone, that the greatest heat rises 
 in the middle. 2. This internally convex 
 form opposes more resistance to the efibrts 
 of the liquid and the action of the heat, 
 3 . The deposites formed in the bath are 
 thrown to the sides of the boder which rest 
 on the brickwork, where the fire is less 
 active, and consequently where there is 
 less danger of their forming a crust, and 
 interposing between the liquid and the 
 metal, which very often occasions the melt¬ 
 ing of the boiler. 
 
 250. “ It has long been a subject of dis¬ 
 pute, what proportions are the most advan¬ 
 tageous to be given to a boiler. From the 
 experiments with which we are acquainted, 
 we may now deduce the following conse¬ 
 quences. The quantity of fuel necessary for 
 evaporation, augments only the volume of 
 the liquid in the same proportion, so that 
 there is an advantage in employing large 
 boilers; but more time is required to bring 
 
BY steam; 
 
 9M 
 
 |bke,latter to ebulUtioiL;, and as time is. an 
 element of calculation in. the interest of the 
 manufacturer, it depends, on, himself, to de¬ 
 termine the dimensions of his boilers.- 
 
 251. Count Rumford kept boiling, at 
 different times, for an hour, four hundred 
 and forty, and; two hundred and eighty 
 pounds of water. .In the first, instance, 
 eighteen pounds of water were kept boiling 
 by one pound of fuel, and in the second, 
 only" twelve pounds. 
 
 ;f r252. “ It may be adopted as, a principle, 
 according to Coimt Rumford, that the sav¬ 
 ing of fuel is greater in,proportion to the 
 length of time necessary for producing 
 ebullition 
 
 . Gauge-Cocks t. . 
 
 . 253.. Ror. small, boilers, a very good mod e 
 is to Jiave one of the gauge-cocks- and pipes 
 laid horizontally, - at- the highest surface 
 proper for the water. ' "When filling the 
 
 “ Cbaptal’s Chemistry, applied to Arts and Manufactures, p, 155—158. 
 f See Art, 166. 
 
 N n • 
 
284 HEATING OF MILLS, &c. 
 
 boiler, the attendant leaves the cock open, 
 and allows the water to run into the boiler, 
 until it runs over at the cock, which in¬ 
 dicates the proper height. 
 
 . METHODS OF CONNECTING STEAM-PIPES. 
 
 Flanches*. 
 
 234. It seems now to be perfectly ascer¬ 
 tained, that the best kind of joint for steam- 
 pipes, whether horizontal or vertical, is that 
 of flanclies, (See Art 153,) but they should 
 have a projecting part on the one pipe, 
 which fits into a recess of the other, to pre¬ 
 vent the cement or jointing from getting 
 into the internal part of the pipe when 
 the joint is screwed up, and, by its rough¬ 
 ness, obstructing the passage of the 'water of 
 
 Spigot and Faucet Joints 
 255. IVhere spigot and faucet pipes are 
 used, in order to remedy their defect for 
 steam-pipes, drill a hole in the direction of 
 the diameter of the pipe, quite thrbugh on 
 both sides, and fit in an iron pin into it, 
 which may project a little on each side. 
 
 * See Art 153. 
 
BY STEAM. 
 
 285 
 
 256. The principal defect found.in the 
 common spigot and faucet joint, when used 
 for steam-pipes, is, that owing to the alter¬ 
 nate expansion and contraction of the metal 
 affecting each particular joint, the cement 
 is apt to break, but when secured by an 
 iron pin, as described above, and the pipes 
 have free liberty to move at one end, this 
 defect is remedied. 
 
 25Y. It is a good method to make the 
 faucets with an inner part, no larger in 
 di- meter than just to fit the spigot. This 
 supports the pipe, independently mf the 
 cement, and prevents the risk of the joint 
 being hurt by any external stress. This 
 inner faucet is commonly made about two 
 inches deep, and has the spigot inserted 
 one inch into it. The practice of some, 
 is to make the outer faucet, or that which 
 contains the cement, six inches deep, for 
 all pipes above six inches diameter j and to 
 make the faucets of all pipes below six 
 inches, the same depth as the diameter of 
 the pipes. 
 
,286 HEATING OF SIILLS, 8ec. 
 
 258. It is usiM’to make the space for 
 the cement, all round* the spigot,- rfiom 
 three-eighths to one-half inch • that -^pidth 
 is required, in order that the cement may 
 be-firmly driven into the joint;. When the 
 space is very narrow, this cannot be done. 
 On the other hand, when too wide, there is 
 a waste of cementy and a risk of injury from 
 unequal expansion. 
 
 Direction and An'angement of the Pipes *. 
 
 259. After they have been allowed to* 
 cool, it is a great advantage, to be able to 
 fill the pipes speedily with steam. The 
 arrangement for that purpose, best suited 
 in heating a cotton-mUl or large building 
 of 'that kind, where the circumstances will 
 permit, is to have one vertical pipe from 
 the boiler^ from which a horizontal pipe 
 branches off into each story, having liberty 
 to expand at the farther end. Mr. Houlds- 
 worth’s mills at Ahderston, are now heated 
 on this arrangement. There is a stop-cock 
 at each of the branches, where it springs 
 fromthevertical pipe. The pipeshaveliberty 
 
 • See Art. 
 
BY STEAM. 287-' 
 
 to expand freely at the farther end, without 
 thei ieast: risk- of breaking, or injuring the 
 joints. But one of the greatest improve¬ 
 ments in heating by steam, which has been 
 yet introduced, is that the expansion of the 
 pipes is made to. regulate the blowing of 
 the air and steam, so as to allow.the pipes 
 to: be speedily .filled, while all unnecessary 
 escape of steam is- prevented.. When the 
 pipes; are. cold, the pipes being at the 
 shortest, they are connected with a puppet- 
 valve,j which they keep open, so that upon 
 the admission of the steam, the air freely 
 escapes, at the further end. By the-time 
 that operation is finished, the pipes grad¬ 
 ually expand, and when . suj05ciently warm, 
 shut the valve, so as to prevent all escape 
 of steam.' . On. the common plan, unless 
 there be a continual escape of steam, the 
 pipes soon become cold.., A patent is at 
 present in progress, for this very ingenious 
 invention of Mr. Houldsworth. 
 
 260. Since the first three Parts of this 
 Treatise were written, the application of 
 steam, to the heating of cotton-mills, and 
 
288 HEATING QE jnLLS, &c. 
 
 for various purposes in other branches of the 
 
 cotton manufacture, has greatly increased. 
 
 PRINTING-OFFICES. 
 
 Case I. 
 
 261. In December, 1812, I was several 
 timesinMr. Dawson’s printing-office*, which 
 has for a considerable time been heated by 
 steam. That gentleman very politely showed 
 me his apparatus, and communicated to me 
 every required information respecting it. 
 Although convinced that the arrangement 
 oTthe steam-pipes is very far from being so 
 simple as it might have been, yet he was 
 fully satisfied of the advantage of the plan. 
 He '.uses ;an inferior quality of coal, (the 
 Ponlop,] and saves very considerably in the 
 premium for insurance. He has 17,000/. 
 insured. Formerly, when he used stoves, 
 he paid 10s. 6d. per cent., now he pays only 
 3s. per cent. 
 
 Case II. 
 
 262. In the year 1811, an apparatus was 
 erected for heating, at a very small expense, 
 
 • White Friars, London. 
 
BY STEAM. 
 
 the Chronicle printing-of&ce, Glasgow, by 
 steam, which continues to give satisfaction. 
 The boiler is placed in the outer writing- 
 room. The. steam-pipes issue thence to 
 the floor of the press-room above, and lye 
 along the middle of the floor. They rise 
 gradually toward the further end, so that 
 the rmter of condensation runs back to the 
 boiler. The joints are of the spigot and 
 faucet ¥indi. 
 
 Observations. 
 
 263. This arrangement is simple, and as 
 water of condensation to the 
 
 boiler, there is a saving of heat, as well as 
 of trouble, by the boiler requiring to be sel¬ 
 dom fed with additional water, to supply 
 the small waste. 
 
 264. The spigot and faucet joints are 
 inferior to jianches, (see Art. 254,) but in 
 this case, they all have answered well, ex¬ 
 cept one, where there is an angle in the 
 pipes, which was not intended, when the 
 arrangement was first planned. This ap¬ 
 paratus v/as constructed at the Port-Dundas 
 Foundery, Glasgow. 
 
290 
 
 HEATING OP JHLLS, &C. 
 
 ■WAUEHOUSES. 1 
 
 265. An apparatus has been lately fitted 
 up in the extensive warehouse of Messrs. 
 ■Walkinshaw & Co. Glasgow. The boiler 
 is placed in the sunk story, thence there is a 
 Vertical pipe, from which there are branches 
 into each floor, rising at the farther end, 
 and l}ing for the most part under the 
 counters. The joints are done with bolted 
 fianches. 
 
 Observations. 
 
 266. The bolted flanches are found to 
 answer well. (See Art. 254.) The obser¬ 
 vations relative to the 'H'otev of condenmtion, 
 made on the heating of the Chronicle Office, 
 (see Art. 261,) are applicable to this case. 
 This apparatus also was constructed at the 
 Port-Dundas Foundery, Glasgow, and gives 
 much satisfaction in its use. 
 
 D\raLLING-HOUSES *. 
 
 Pitlcellony House. 
 
 267. Pitkellony house in Perthshire, hav¬ 
 ing been damp and cold in the passages, 
 
 ’ See Art 177, 178. 179. 
 
Mri Adam had, about the year 1810, an 
 apparatus put up for heating the passages^ 
 stair-case, and some of the rooms, by steam, 
 lire farm-yard and offices are near the 
 house. It is heated by a boiler which stands 
 in the out-house where the potatoes for 
 feeding the cattle are steamed. The pipe 
 conveys steam into three pillars in the pas¬ 
 sages in the lower part of the house, and 
 in the stair-case. In each of the rooms 
 which are heated by steam there is a steam- 
 chest. The steam and air are blown off 
 from a small pipe which passes into the 
 external air. The rooms are seldom heated, 
 but the dampness of the passages and stair¬ 
 case require, during winter, the daily use of 
 steam, which answers perfectly. 
 
 Counting-Room at Kaidal. 
 
 268. Messrs. Braithwait, at Kendal, have 
 for some years had their counting-room 
 heated by steam. It is done in a very pecu¬ 
 liar mode, and on what may be termed a 
 new principle. In the room there is a small 
 rectangular boiler, having its furnace includ¬ 
 ed in a rectanglar cast-iron case, the whole 
 
292 HEATING OF MILLS, &c. 
 
 having the appearance of a chest standing 
 against the wall. From the boiler a small 
 pipe proceeds to the condenser, a copper 
 vessel 18 inches diameter and 2 feet high, 
 placed under a double writing-desk. The 
 condenser is made on the plan of the im¬ 
 proved cylindrical refrigeratories used by 
 chemists in distillation; a very small quan¬ 
 tity of steam is allowed to escape at the 
 top, but it is condensed against the lid, so 
 that none of it gets into the room. 
 
 269. The effect of this: apparatus, is to 
 form a reservoir of heat; for the steam gives 
 out its heat to the water in the condenser, 
 which, when warm, retains the heat for 
 many hours. The fire requires to be kept 
 on only three hours in the morning, and 
 the room remains comfortable the rest of 
 the day and evening. 
 
 • Ohser'valions. 
 
 270. This may be considered as a new 
 application of steam in heating; and might 
 be applied with advantage, in situations 
 where attendance could not be regularly 
 
BY STEAM. 
 
 given to the fire; for instance, in the case 
 of hot-houses. (See Art. 210.) Steam applied 
 in the common wa}^, however, begins to 
 come into use for heating hot-houses. 
 
 Mr. Rucker’s Blouse. 
 
 271. Mr. Rucker has for more than ten 
 years had his house (about eight miles from 
 London, and one of the most magnificent 
 in England) partly heated by steam. It was 
 done with copper steam-pipes, which were 
 incased in other pipes of greater diameter, 
 leaving a space around them, into which 
 the external air was introduced, and which 
 when heated, was conveyed into several 
 apartments; but the apparatus was found 
 defective in the following particulars;—A 
 loud unpleasant noise arose when the pipes 
 were filling with steam;—the 'water of con¬ 
 densation escaped at every joint;—and the 
 heated air was not produced in sufficient 
 quantity to make the rooms comfortably 
 warm. When consulted on the subject, I 
 proposed substituting cast-iron steam-pipes, 
 for those of copper, with several other al¬ 
 terations, which have since been executed, 
 
294 HExVTING. OF MILLS, &c. 
 
 under tlie direction of Mr. E. Stuart Meikle- 
 
 ham. Architect, 2, Staple’s Inn, London. 
 
 Inn at Johnston. 
 
 272. The heating of the Inn at Johnston 
 (see Art. 179) has been relinquished, not 
 on account of its not answering the pui'pose, 
 but for the reasons assigned by hlr. Neil 
 Snodgrass *, in his letter to nia of 16th 
 January last. 
 
 “ Johmton, IQih January^ 1815. 
 
 “ Dear Sir, 
 
 , (Extract)—“ The cause of relinquish¬ 
 ing the heating of the Inn of this place, by 
 steam, arose from the change of landlords; 
 Mr. Hodgait the proprietor, had extensive 
 views, (when he began that system,) of a 
 steam-kitchen, a large ball-room, &c. but in 
 ,a short time thereafter, he let the Inn, and 
 relinquished the business, before the plan 
 was completed. The tenant, ignorant of 
 every thing relative to steam, and in limited 
 circumstances, was even afraid of the very 
 
 * This geatleman Tvas the inventer of the improved scutching machine 
 for cleaning cc-tton. 
 
BY STEAM. 
 
 295 
 
 name of steam-heat, and all at oiAce gaye 
 it up, without a day’s trial, after he came into 
 possession; and thus without the shadow 
 df a reason, it was given up,—1 am, 
 
 “ Dear Sir, 
 
 Yours respectfully, 
 
 «N. SNODGRASS.” 
 
 Netherly House, 
 
 273. T was applied to respecting the 
 heating of a part of Netherly House by 
 steam, but I find from the following letter, 
 from Mr. Ellis, Sir James Graham’s agent, 
 that he was not fortunate in getting the 
 work properly executed, particularly the 
 joints of the pipes. 
 
 Btish-Fam, Longiom, Jan. 1815. 
 
 “ Sie, 
 
 (Extract)—“ I have your letter of 
 the 7th instant.—In answer to it, I beg to 
 inform you, that the passage at Netherly 
 is now heated with steam. The boiler is 
 placed in the wash-house, and it supplies 
 hot water for washing, and for a small bath 
 
296 HEATING OF MILLS, &C. 
 
 in an adjoining room, through which the 
 ste^-pipes pass a small dressing-room 
 and a water-closet, and then enter the 
 passage, which is about 90 feet long. The 
 passage at the farther end from the boiler, 
 is 18 inches above the level of the lower 
 end, the ceiling and floor falling together 
 without a step, consequently, we were 
 obliged to take ofi* the condensed water 
 at the boiler end, as the situation did not 
 admit of the pipe being lowered at the 
 farther end, and although it was provided 
 with an air-cock, and a pipe with a siphon, 
 to take away any condensed water that 
 might be forced to the end of the pipe, it 
 requires a great force of fire to heat the 
 passage, which is only about 6 feet wide, 
 8 feet high, and the pipe 4 inches diarrieter. 
 The joints were badly executed, and did 
 not prove drop-tight.— I am, 
 
 “ Sir, 
 
 “ Your most obedt-Serv‘- 
 « L. ELLIS.” 
 
BY STEAM. 
 
 297 
 
 PUBLIC BUILDINGS. 
 
 West Church, Aberdeen. 
 
 274. The West Church of Aberdeen 
 has been for some years heated by steam. 
 James Hadden, Esq. then first magistrate of 
 that city, honoured me with the following 
 letter. 
 
 “ Aberdeen, 6th July, 1811. 
 
 “Sir, - 
 
 “ It being found expedient to 
 warm the principal Church in this city, 
 and conceiving the best mode of doing so 
 may be by steam, a plan for the purpose 
 has been made out. As you are conversant 
 in steam-heating, I trouble you with a plan 
 of our Church, and tire mode of heating it 
 proposed, requesting you will give me yoim' 
 opinion of it, as well as the size of a boiler 
 that may be necessary; only you will please 
 have in view, to warm, by the same boiler, 
 another Church about the same size, at 
 the end of the one now laid down. The 
 pipes are proposed to be laid down into 
 the ground with iron plates for coverings, 
 
298 HEATING OP MILLS, &c. 
 
 in order not to disfigure the Church.—- 
 I am, 
 
 “ SiK, 
 
 “With respect,. &c. 
 
 “ JAMES HADDEN.” 
 
 275. I accordingly made such remarks 
 as occurred to me, and took the liberty of 
 suggest^ some alterations on the plan. 
 It has since been executed and has given 
 much satisfaction, as appears from the fol¬ 
 lowing letter from Mr. Alexander Cooper. 
 
 “ Aberdeen, Febi'uary, 1813. 
 
 - “ Dear Sir, 
 
 “ I am favoured with yours 
 of the 21st January, and shall consider it 
 a pleasure to be of any service to you. 
 The plan of heating the West Church with 
 steam has been executed, and gives perfect 
 satisfection. 1 this morning saw Mr. John 
 Smith, the Architect, who executed the 
 work, and who is a man of considerable 
 taste and ingenuity. I have from his in¬ 
 formation subjoined a few particulars in 
 elucidation. 
 
■ BY STEAM. 299 
 
 “ The boiler contains above 300 cubic 
 feet, having been intended for heating a 
 neighbouring church also, but even for both 
 it would be too large. It was made much 
 larger than ordered, and placed so high that 
 the condensed steam cannot be returned. 
 The pressure of the steam is measured by 
 a steam-gauge, (^such as is used by Fenton, 
 Murray, Wood, , & Co. Engine-Makers, 
 Leeds,) on which it indicates 6 or 7 de¬ 
 grees, but never more. : 
 
 “ Consumption of English coals, about 
 one-and-a-half bolls, at each heating, (thirty- 
 six stone, Amsterdam, per boll.) The pipes 
 have 668 feet of surface to 194,022 cubic 
 feet of space; The fire is put to the boiler 
 on Saturday evening, and continues until 
 the congregation meet; in the afternoon. 
 The temperature of the church is from 46" 
 to 48", Fahr. and the presence of the con¬ 
 gregation raises it to 50"—55". The pipe- 
 tunnel being covered with perforated cast- 
 iron plates, the heat ascends with some little 
 difficulty, and to obviate this, a few plates 
 Pp 
 
300 HEATIKG OF MILLS, &c. 
 
 here and there are removed, imtil the 
 
 congregation are to meet.—am, 
 
 “ Dear Sir, 
 
 “ Yours respectfully, 
 “A. COOPER.” 
 
 276. This Church is built of free-stone, 
 with massive square pillars of the same 
 material, in the inside; neither the pillars 
 nor walls are plaistered, nor done with 
 wainscot. 
 
 Meeting-kouse at Kendal. 
 
 277. The Society of Friends at Kendal, 
 had their Meeting-house heated by steam, 
 some years previous to the time I saw it, 
 which was in the . summer of 1811. The 
 apparatus is exceedingly weU arranged, and 
 the workmanship well executed, and it was 
 done at a very small expense. The whole 
 was designed and executed under the eye 
 of Mr. George Braithwait, a member of that 
 respectable Society, who is distinguished 
 for his ingenuity and scientific knowledge. 
 
BY STEAM. 
 
 301 
 
 278. This Chapel is heated by 8 steam- 
 pipes, of 4 inches external diameter. The 
 whole space is about 26,640 cubic feet, 370 
 cubic feet of space are heated by one foot 
 surface of steam-pipe. The pipes are placed 
 under the back-seats, where no inconven¬ 
 ience is experienced by the sitters, while the 
 rest of the Chapel is comfortably warm. 
 The water of condensation runs back to the 
 boiler, which is placed in an adjoining a- 
 partment, nearly as large as the Chapel. 
 The boiler and flues make this apartment 
 also comfortably warm. 
 
 The Fortico at Manchester. 
 
 279. The Piiblic-Room and Library at 
 Manchester, called the Portico, has ever 
 since its completion been heated by steam. 
 The boiler is placed in the cellar, the steam- 
 pipes are placed within the wooden columns 
 %vhich stand in the large room. The air 
 and steam are blown off by small leaden 
 pipes which descend from the top of the 
 pipes into the cellar. 
 
HEATING OF MIILS, &c. 
 
 BATHS. 
 
 280. Various methods have been em¬ 
 ployed for heating the water for baths. ’ In 
 some cases, steam is used to heat the water 
 in the bath. At Sir Arthur Clark’s public 
 baths, Dublin, the water is heated by steam 
 in a separate vessel. At the Leith baths, 
 steam is not used for heating the water, and 
 it is never allowed to be of a higher tem¬ 
 perature than 150°, and is conveyed directly 
 from the boiler to the baths. 
 
 281. At Mr. Harley’s baths, Glasgow, it is 
 brought to the boiling point, and mixed with 
 cold water, to have it of the temperature re¬ 
 quired. This last mode, I recommended for 
 theproposedpublic baths at Largs*, as being 
 found to answer well in practice, and as not 
 requiring a boiler nearly so large and ex¬ 
 pensive as the plan adopted at Leith, while 
 it has the fiirther advantage, that the boiler 
 may be employed for generating steam for 
 the vapour-baths, and for heating any part 
 of the building. Besides that advantage. 
 
 ' On the sca-cnnst of Airsliirci 
 
BY STEAM. 
 
 303 
 
 whatever water goes . off in the form of 
 steam, leaves the remainder stronger, or 
 in other vs^ords, contains more salt than it 
 would otherwise contain. 
 
 282. At Mr. Harley’s baths, in each of 
 the rooms of the hot-baths, there is a square 
 vessel, kept full of hot water, by being at¬ 
 tached to, and communicating with, tlie hot 
 water-pipes, which serves to keep the towels 
 dry and warm. 
 
 283. Mr. Harley’s baths, taken as a whole, 
 are perhaps the most complete in the king¬ 
 dom. He applies steam very extensively 
 to other parts of his extensive and useful 
 establishments. It is but justice to Mr. 
 Harley, to say, that he has by his exertions 
 greatly improved a formerly unsightly part 
 of the town, and contributed much to the 
 accommodation and health of its inhabitants. 
 
 284. In connection with the baths, there 
 is a public washing-house; and adjoining 
 the byre, or cow-houses, already well known 
 
 for their excellent construction i and coin- 
 
304 HEATING OF MILLS, &C. 
 
 plete system of cleanliness and manage¬ 
 ment. He uses a steam-engine for driving 
 various kinds of macMnes, for the use of 
 his establishment, and the same boiler 
 serves to steam the potatoes and other 
 kinds of food for the cattle. 
 
 285. The application of steam, for pre¬ 
 paring food for cattle, as well as for cooking 
 victuals, has beenlong known and approved; 
 but it is perhaps not so generally known, 
 that tough and gristly meat is much im¬ 
 proved when cooked by steam. 
 
 Observations, 
 
 286. Dr. Kentish, at Clifton, near Bristol, 
 suggested a plan for having their establish¬ 
 ment formed for invalids, in a building to be 
 kept always at a regidar mild temperature, 
 which he intends to call a Madeira-house. 
 See the Philosophical Magazine for 1818, 
 1814. Steam would certainly be well 
 adapted to the purpose of producing such 
 an artificial mild climate. 
 
■BY STEAM. 
 
 ' , t05 
 
 287. Two of the steam-boats on the Clyde 
 have their cabins heated by steam, which 
 may in some measure serve to show the 
 practicability of heating ships by that agent. 
 Where there is so much combustible matter 
 as in ships of war, it would seem to promise 
 much advantage; but those who are better 
 acquainted with nautical affairs, can better 
 judge how far this safe mode of heating 
 might be applicable to that purpose. See 
 Art. 210, note. 
 
 SECTION III. 
 
 ON HEATING AND DRYING BY STEAM. 
 
 288. On this branch of the subject I have 
 little to add to what is said in Part III. 
 Messrs. Muir, Brown, & Co. (See Art. 181) 
 have greatly extended their apparatus for 
 heating and drying by steam, a proof of 
 their being convinced of its advantage. 
 The same may be said of almost all the 
 calico printers in the trade. It has also 
 with great benefit been applied to lessen 
 the danger in the manufacture of gun¬ 
 powder. 
 
306 HEATING OF MILLS, &C. BY STEAM. 
 
 289. In many of the most improved oil 
 mills, the chaufer-pan ds now heated by 
 steam, instead of charcoal. This mode is 
 found to give proper heat with greater 
 precision, than can be dons with a charcoal 
 fire. 
 
^F^JPEJVBIX. 
 
 MISCELLANEOUS OBSERVATIONS ON CHIMNEY FIRE¬ 
 PLACES, PARTICULARLY THOSE USED IN IRELAND. 
 
 290. It has frequently been a subject of 
 inquiry, whether the ancients were ac¬ 
 quainted with chimneys, or open fire-places. 
 In the houses discovered at Herculaneum 
 and Pompeii, there are no chimneys: they 
 all appear to have been warmed by furnaces 
 and flues. 
 
 291. It may be presumed, that, though 
 6ne or more expressions of ancient authors 
 may appear to allude to a chimney, if the 
 ancients were acquainted with the art of 
 constructing, in mason-work, elevated fun¬ 
 nels for conveying away the smoke, it must 
 Q q 
 
APPENDIX. 
 
 be allowed, when we consider the many 
 proofs that occur to the contrary, that they 
 were, to say the least, extremely rare. 
 
 292. It is not known at what time chim¬ 
 neys began to be used. The writers of the 
 14th century seem either to have been un¬ 
 acquainted with chimneys, or to have con¬ 
 sidered them as the newest invention of 
 luxury. That' there were no chimneys in 
 the 10th, 12th, and 13th centuries, has been 
 presumed from the terms “ ignitegkm ” or 
 “ inprifegium,” the curfew-bell of the Eng¬ 
 lish, and couvr^eu of the French; which 
 seem- to intimate, that the people made 
 fires in their houses in a hole or pit in the 
 centre of the floor, under an opening formed 
 in the roof; and when the fire was bm-ned 
 out, or the family went to bed at night, the 
 hole was shut by a cover of wood. 
 
 ^ 293. The oldest certain account of chimr 
 neys, is in the year 134'7 *. An inscrip¬ 
 tion at Venice, records that at the above 
 period a great many chimneys (molti ca- 
 
 * See Beckmann’s History of Inventions, Tok II. p. 103. 
 
APPENDIX. 
 
 mini) were thrown down by an earthquake. 
 The first chimney-sweepers in Germany 
 came from Savoy, Piedmont, and the neigh¬ 
 bouring territories; and these for a long time 
 were the only countries where the cleaning 
 of chimneys was followed as a trade. Hence 
 it is conjectured, that chimneys were in¬ 
 vented in Italy. 
 
 294. It may be observed, that in the 
 countries of modern Europe, the use of 
 stoves prevail throughout the north; while 
 in France and Great Britain, open fires are 
 used. In the warm countries of Italy and 
 Spain, there are very few chimneys, and 
 the only method usually practised of tem¬ 
 pering the cold, which is sometimes severely 
 felt, is to burn charcoal in portable brasiers. 
 
 295. A chimney consists of a fire-place, 
 in which the fuel is consumed, and a flue 
 to carry off" the smoke and vapour arising 
 from the combustion; thus affording the 
 benefit of the heat of a fire without the in¬ 
 convenience of its smoke. But these ob¬ 
 jects were, and still are, very imperfectly 
 
310 APPENDIX. 
 
 attained; a large portion of the fuel being 
 
 wasted without increasing the warmth of the 
 
 apartment. 
 
 296. Dr. Franklin, in 1785, published 
 “ Observations on the Cause and Cure of 
 Smoky Chimneys.” He has very satisfac- 
 tordj- explained all the usual causes of this 
 defect, and shown their remedies. To this 
 pamphlet succeeded the “ Essay ” of Count 
 Rumfprd, in 1796, whose improvements in 
 the construction of fire-places have been 
 very generally adopted, These two works 
 together, form a valuable body pf informa-r 
 tipn. They are well known to the publie, 
 but it is not sp generally known, that ex^ 
 actly a hundred years agp, viz. in the year 
 1715, Dr. Desagulier published his bopk, 
 entitled “ Fires Improved, being a new 
 method of Building Chimneys, sp as tP pre¬ 
 vent their smoking, &c,” which is a ti’ans^ 
 lation of a stUl older work fi-ona the French 
 of M. Gauger, which shows that the most, if 
 not all, the principles pointed out by Count 
 Rumfordwere understood, and are explained 
 by M. Gauger. He also proposed seven 
 
APPENDIX. 
 
 311 
 
 difFerent constructions of cbimneys,in wHicb 
 there are hollow cavities made by iron plates 
 in the bach jambs and hearth, through which 
 plates the heat passing warms the air in 
 those cavities, which is continually coming 
 into the room fresh and warm. This con¬ 
 struction had many obvious advantages; 
 but the expense and difficulty attending it, 
 at that early period, discouraged the propa¬ 
 gation of the invention. In our own timesj 
 however, similar constructions have been 
 brought forward as new, probably without 
 the knowledge of what had been done so 
 long before, and therefore with all the merit 
 of invention. 
 
 297. To determine in what manner a 
 
 room is heated by an open chimneyffirej 
 it will be necessary to find out under.’wliat 
 /om.theiheat generated in the combustion 
 of the fuel, exists, and then to see howut is 
 communicated to those bodies which are 
 heated by it. ; . 
 
 298. In regard to the first of these sub¬ 
 jects of inquiry, it is certain that the heat 
 
APPENDIX. 
 
 312 
 
 which is generated in the combustion of 
 the fuel, exists xmder two perfectly distinct 
 and different forms. One part of it is com- 
 hined with the smoke, vapour, and heated 
 air, which rise from the burning fuel, and 
 goes off with them into the upper regions 
 of the atmosphere, which is termed the mn- 
 bined heat, while the other part which ap¬ 
 pears to be uncombined, or combined only 
 with light, is sent off from the fire in rays, 
 in all directions, and is teiined radiated 
 heat. With respect to the second subject 
 of inquiry, it is highly probable that the 
 combined heat can only be communicated 
 to other bodies by actual contact with the 
 body with which it is combined; and with 
 regard to the rays which are sent off by the 
 burning fuel, it is certain that they com¬ 
 municate or generate heat only when and 
 where they are stopped or absorbed. In 
 passing through air which is transparent, 
 they certainly do not communicate any heat 
 to it; and it seems highly probable that they 
 do not communicate heat to solid bodies by 
 which they are reflected. 
 
APPENDIX. 
 
 .313 
 
 299. A question which naturally presents 
 itself here, is, What proportion does the 
 radiant heat bear to the combined heat?— 
 Though that point has not been determined 
 with any considerable precision, it is, how¬ 
 ever, certain, that the quantity of heat which 
 goes olF combined with the smoke, vapour, 
 and heated air, is much more considerable 
 than that which is sent olF from the fire in 
 rays; and yet small as the quantity is of 
 this radiant heat, it is the only part of the 
 heat generated by the combustion of fuel in 
 an open fire-place, which ever is, or indeed 
 ever can be, employed in heating a room. 
 The whole of the combined heat escapes by 
 the chimney,, and is totally lost; and no 
 part of it could ever be brought into a 
 room from an open fire-place, without 
 bringing along with it the smoke, with 
 which it is combined. 
 
 300. Many of the diseases proceeding 
 from colds, may be ascribed to strong draw¬ 
 ing chimneys, whereby, in severe weather, 
 people are scorched in one part, while they 
 are frozen in another. These fire-places are 
 
APPENDIX. 
 
 314 . 
 
 of little use iii warming a room, because the 
 air around them which is warmed by the 
 direct rays of the fire, does not continue in 
 the room, but is continually collected into 
 the chimney, by the current of cold air 
 coming behind it, and is presently carried 
 off. Besides, the greater part of the fire is 
 often lost, being absorbed by the back jambs 
 and hearth. 
 
 301. In such parts of Ireland as I have 
 visited, the chimney fire-places are con¬ 
 structed in a way that appears to me Well 
 calculated to remedy, in some degree, the 
 defects which have been mentioned, and to 
 economise fuel. Probably its high price in 
 many parts of that island, prompted greater 
 attention to the subject than with us, where 
 it is abundant. The grates are wide; the 
 space from back to front is small; so that 
 a great surface of the coals is exposed to 
 send out the radiant heat. The space above 
 the grate is shut in by a piece of stone, 
 about II inch thickj cut out in the form of 
 an arch over the grate. The back is formed 
 into an ehptical niche, leaving only a very- 
 
AP^E^fDlX. 
 
 SIS 
 
 siittall opefiing fot the smoke to escape up 
 the chimney. Fig. 2,- Plate III, is a sketch 
 of one of these grates, frorii memory; the 
 sketches and dimensions which I took on 
 the spet haiving been unfortunately lost. 
 
 ABCD represent the grate, ,AEGB is a 
 thin front-plate of stone, AI'IB the arch 
 fei-ming the front of the niche, I the back, 
 iCL the throat; 
 
 302. The effect of this construction, is, 
 that the combined heat and part of the radiant 
 heat acting on the curved back, (which should 
 be formed oi fire-brick or fire-stone,) heats 
 it, and like a concave mirror, reflects it into 
 the room, while the narrowness of the throat 
 prevents a great deal of unnecessary escape 
 of heated air up the chimney. 
 
 303. When I first observed one of these 
 chimneys at Belfast, I supposed the land¬ 
 lord to be a man of some science, but was' 
 surprised to find, in pursuing my journey 
 from Belfast to Dublin, and even 80 miles 
 more to the south, that this construction 
 
 R r 
 
APPENDIX. 
 
 316 
 
 prevails, from the lowest inns to the houses 
 of the opulent, the only difference being 
 in the degree of ornament. 
 
 304. But a still more perfect method of 
 heating apartments in temperate climates, 
 where we have the cheerful appearance of 
 an open fire, is what we call a stove-grate, 
 of which there are a variety of constructions 
 now in use, some of which were mentioned 
 when speaking of M. Gauger’s work. On 
 some parts of the Continent, it is called 
 chapelle, from its resemblance to the chapels 
 or oratories in great churches. 
 
 305. In the great chimney-piece, which 
 in this case may. be made even larger than 
 ordinary, is set a smaller one, fitted up in 
 the same style of ornament, but of a size 
 no greater than is sufficient for holding the 
 fuel. The sides and back of it are made of 
 iron, and are kept at a small distance from 
 the sides and back of the main chimney- 
 piece, and are continued down to the hearth, 
 so, that the ash-pit is also separated. The 
 pipe or chimney of the stove-grate is car- 
 
APPENDIX. 
 
 Sir 
 
 tied up behind the ornaments of the mantel¬ 
 piece, till it rises above the mantel-piece 
 of the main chimney-piece, and is fitted 
 with a register or damper plate. All the 
 rest of the chimney is covered with iron- 
 plates or brick-work. 
 
 306. The effect of this construction is 
 very obvious. The fuel being in immediate 
 contact with die back and sides of the grate, 
 heats them to a high degree, and they heat 
 the air contiguous to them. This heated 
 air cannot get up the chimney, because 
 the passages above these spaces are shut up. 
 It therefore comes out into the room; some 
 of it goes into the real fire-place, and is 
 carried up the chimney, and the rest rises 
 to the ceiling, and is diffused over the room. 
 Less than one-fourth of the fuel consumed 
 in an ordinary fire-place is sufficient; and 
 this with the same cheerful appearance and 
 salutary renewaLof air. 
 
 307. Mr. Moser, Ironmonger, of Frith- 
 Street, Soho, London, manufactures stove- 
 grates very nearly on this principle, in an 
 
318 Appproix, 
 
 ele^nt manner, The air does not eoine in 
 imniediate contact with the iron parts of the 
 stove-grate, but passes through thin boxes 
 or retorts pf earthen-ware, which prevents 
 the airfiropa being contaminated, as it would 
 be by coming into contact with iron in a 
 high temperature. 
 
 308. The Church of Christ-Church Hos^ 
 pital, London, is heated by one of Mr. Mg-r 
 ser’s stove-grates, in the middle of the cen-, 
 tre area. Also that much admired structure 
 of Sir Christopher Wren, St. Stephen’s, 
 Walbrook, is heated by two of those stove- 
 grates, placed in opposite sides of the 
 Church *. 
 
 * See “ Fires Improved, being a new method of building Chimneys so .as 
 to prevent their smoking, in which a small fire shall warm a room better 
 than amncfa larger, made the common way. With the manner of altering 
 snch chimneys as are, already built, so that they shall perform the same 
 effects, ninstraied with Cuts. Written in Fren cb, by Monsieur Gaugee : 
 made English and improved by J. T. Desactoieks, UL A. F. R. S. 
 By whom is a d de d , the manner of making coal fires as useful this new 
 way, as the wood fires proposed by the French author: explained by an 
 additional plate. The whole being suited to the capacity of the meanest 
 
 “ Observations on the Causes and Cure of Smoky Chimneys, by Dr. 
 Feakklis.” 
 
 “ Count Kumeoed’s Essays on Chimney Fire-Places.” 
 
 “ Encyclopedia Britamiica,” article Pneumatics. 
 
 '• Dr. Sees’ Encyclopedia,” article Chimuey and Pire-Placc. 0 
 
ARPSNBiS, 
 
 319 
 
 ON STOVES. 
 
 :809. The construetion of stoves is ex¬ 
 ceedingly various, although their general 
 principles are simple. 
 
 310. Stoves, in general, may be defined 
 to be fire-places enclosed on a,11 sides, having 
 only a passage to support the fire, under a 
 tube, for carrying ofP the smoke. The air 
 of the apartment is warmed by coming in 
 contact with the outside of the stove or 
 flue. 
 
 311. The effect of a stove, made on this 
 principle, depends much on retaining the 
 air, already heated by it, in the room. This 
 is so remarkably the case, that a small open 
 fire in the same room will be so far from 
 increasing its heat, that it will greatly di¬ 
 minish it, by diwing in the external air. 
 
 312. On the Continent of Europe, where 
 fuel is scarce, especially towards the north, 
 much care and ingenuity has been displayed 
 in the construction of stoves, combining 
 
APPENDIX. 
 
 elegance with economy. The air of a room 
 may be equally warmed, either by using a 
 small stove, made very hot, or a much 
 larger stove, more moderately heated. 
 
 313. The first kind is chiefly used in 
 Holland, Flanders, and the milder climates 
 of Germany and Poland. The last kind 
 are universally used in the fiozen climates 
 of Russia and Sweden. 
 
 314. The first, are generally maide of cast- 
 iron*, and the last, of brick-work, or rather 
 glazed tiles, and are constructed on excellent 
 principlesi The Russian stove is a sort of 
 magazine, in which a great quantity of heat 
 is accumidated, to be afterward slowly com¬ 
 municated to the air of the apartment. It 
 is therefore built extremely massive. Its 
 internal structure is that of a long pipe of 
 flue, returned backward and forward. Tlie 
 
 * At the Port-Dundas Foundery, Glasgow, a variety of improved iroii- 
 stoyes are mamifartured. One kind is peculiarly convenient^ where a 
 fire is wanted to he kept in all nighk with hardly any consumption of 
 fiieL By means of a roister, at any moment it may he made to bum 
 briskly. These stoves are sold by Mr. Kobert Anderson, Ironmonger, 
 
APPENDIX. 321 
 
 fire-place is below, and is shut in with a 
 small door, after the fire is consumed. So 
 long as any blue flame appears on the char¬ 
 coal it is kept open, in order that the fuel 
 maybe thoroughly consumed. The manage¬ 
 ment which this requires, is the principal in¬ 
 convenience of the Russian stoves. If it be 
 not reduced to ashes before the door is shut, 
 it exposes people to imminent danger of 
 suffocation, by fixed air, and many fatal 
 accidents have happened from this cause. 
 There are many instances known in which 
 people have lost their lives in this manner. 
 In those countries, the windows in winter 
 are generally double, to increase the effect 
 of the stove. 
 
 315. Since the increase of the manufacture 
 of cotton in this island, stoves have been 
 much used in various buildings appropriated 
 to that business. I shall here make some 
 observations upon those which have been 
 used for that purpose. 
 
 316. Till of late years, almost all cotton- 
 mills were heated by stoves. Those origi- 
 
APMNfilX. 
 
 nally used, were what are called coakles or 
 round stoves of cast-iron, according to the 
 size of the rooms; one or more of those 
 stoves were used for carrying ojff the smoke, 
 having a horizontal pipe, and communicat¬ 
 ing more heat to the room. 
 
 317. This plan, although very effectual 
 in point of warmth, is very defective in the 
 three following respects: 
 
 1st. In Cleanlmess. They occasion much 
 ashes and dust in the apartments. 
 
 ^ In Salubrity. The pipes being red 
 hot, or even only heated to a high degree, 
 contaminate the air, by burning the small 
 particles of dust floating in it, or, as JMr. 
 Dalton supposes, by decomposing the water 
 suspended in the air, by which hydrogen 
 is evolved, and a very disagreeable and op¬ 
 pressive smell produced. 
 
 3d. In Safety. It is evident, that stoves 
 so exposed are veiy dangerous in any budd¬ 
 ing, but more particularly so in cotton- 
 
jvp^Nflix. .323 
 
 miUs, amid a:gpantil;y qf so Idglily-com- 
 ,blisi;ible materials. 
 
 318. ,These,i|icpny,eniences , having been 
 -spripusljjfplt,, another plan . w^as tried, viz. 
 •that of placing the stove in a separate 
 ^apartni.ent, enclosing it with brick-work, 
 ;J?avh>g^,J^plpw^ pnlj ..an ppening for . the air, 
 3yhich,heing,rare%d, passed up a flue, and 
 ..by mpans.pf registers,, was introduced mto 
 .the.yaripus . apartnaents. This plan i^yas in 
 ,s,pnie n’espects a grpat improvement. In 
 many, instances,. Ijpwever, the, principle was 
 ill .applied, „ apd. from. an inj udicious con- 
 .-st^uction, the .air \yas not only rendered 
 . .npjdpus, hut from the. Intense heat of the 
 cpal^e, >niany,accidents ^ happened by fire; 
 .andjit. is ,an ..ascertained.faqt,, that a lai-ge 
 ..pyopprtion.,pf, the aq^dentaf, fires which 
 ..haveJiappened in mills,, originated from ill 
 pply, however, as 
 T; have said, from an injudicious construction, 
 
 , ihpt these accidents' occurred. The fault 
 prmcipally^.u'as, that the surface of the, iron 
 . cpakle and pipe was too small in propor- 
 ...tipn .to the. area. of building to be heated. 
 
APPENDIX. 
 
 This, of course, required the iron to be made 
 red hot. The surface ought to have been 
 greater, and the heat more moderate; instead 
 of which, the surface was generally small, and 
 the heat intense. But the greatest defect 
 of this kind of stove was, that the air 
 which was heated by it, did not come suf¬ 
 ficiently near to the surface of the iron stove 
 to carry off the heat as fast as it was gen¬ 
 erated. The effect accordingly was, that by 
 this confined heat, the coakle was very soon 
 burned through. The hot air having pre¬ 
 viously rendered the wood very combusti¬ 
 ble, as soon as the fire had burned through 
 the coakle, the timber was very apt to take 
 fire,andoccasion the destruction of the budd¬ 
 ing; and even when this accident did not 
 occur, the atmosphere of the apartments 
 must have been much contaminated by the 
 adust air proceeding from the fire within 
 the coakle. This kind of stove, so long ago 
 used in cotton-mills, and afterwards, for the 
 reasons above stated, abandoned, has lately 
 been brought forward as a new invention, 
 and a patent obtained for it. The new 
 Church in Charlotte-Square, and a number 
 
APPENDIX. 
 
 325 
 
 of other buildings in Edinburgh, have been 
 recently heated on this plan; which cir¬ 
 cumstance shows, that science alone is not 
 sufficient to bring things to that degree of 
 perfection, which is often attained by prac¬ 
 tical men, where they are prompted by their 
 necessities or interests, aided by experience. 
 Wliile the imperfections of those stoves, in 
 many instances, instigated the heating of 
 cotton-miUs and other manufactories by 
 steam, it also led to greater improvement 
 in the stoves themselves. 
 
 819. I shall now proceed to mention two 
 other kinds, constructed upon better prin¬ 
 ciples ; the first kind is probably the least 
 expensive, the second more perfect, both 
 in regard to safety and to the economy 
 of fuel. These two stoves are constructed 
 on the same general principles as those 
 already described, but on a superior modi¬ 
 fication of those principles; the air in them 
 being brought to rush in more rapidly 
 on the coakle. The coakle, which is an 
 inverted vessel, (in one case, square; in 
 the other, dome-shaped,) made of iron, 
 
326 ATPENBIX. 
 
 and having no opening either on the top 
 or on the sides; the smoke being carried 
 off below, receives nihch more liei^t fi*6hi 
 the fire within, than the stoves above 
 described. The advantage of tho air im¬ 
 pinging strongly on the coakle,' isf, fcat 
 the heat is carried off into tlie apartihents 
 nearly as fast as it is genmated. This ntay 
 be illustrated by the case of a boiler. While 
 clean at the bottom, and filled,' at least 
 partly, with water, the water absorbs the 
 Iieat as fast as it is geherated, aiid the fire 
 does no harm to the metal. But if the 
 boiler be empty, the air being a less perfect 
 conductor of heat than ivater, the boiler is 
 soon burned through. Or, if the watei’ be 
 impure, so as to deposit a sediment, thereby 
 increasing the thickness bf the bottom, and 
 this sediment being a less perfect conductor 
 tliaii the water and the metal itself, the latter 
 will soon be burned oiit. Helice the evil of 
 water containing much lime or other im¬ 
 purities, when used for the boiler of a 
 steam-engine. 
 
 320. Tlie stove, represented in Plate lit. 
 Fig. 3, Nos. 1 and 2, was erected in the 
 
AT^PENDIX. 
 
 327 
 
 y6ar 1816, under illy direction', in a cotton- 
 iniliv About the same time, I erected two- 
 more for other cotton-mills. All these 
 stoves continue to give satisfaction, a:nd' 
 they have never (so far as is known to' their 
 proprietors) required any repair.- These 
 stoves are still at work in the neighbour¬ 
 hood of Glasgow. 
 
 321. The accompanying description of 
 the stove, (that upon the construction of 
 Mr. Strutt oi' Derbjj) represented in Fig. 
 3, No. 1, is so miniitej that the stove shown 
 in Fig; 4, Nos. 1 and 2, (constructed by 
 Mr. Murray of Leeds,) will be easily coih- 
 prehfehded from inspection. I may, how¬ 
 ever, mention, that No. 2 has the pauj or 
 coaklej made of cast-iron, and that it has 
 been used^ for at least seven years, for heat¬ 
 ing a flax-mill. 
 
 322. It should be observed, that in all 
 the cases of heated air-stoves, mentioned 
 above, they have been found defective in 
 as far as i*elates to the heating of the /owesi 
 fiaor, the local situations not permitting 
 the stoves to be placed sufficiently low. 
 
APPENDIX. 
 
 323. A very great improvement has been 
 lately made, by Mr. WiUiam Strutt of Der¬ 
 by, in those air-stoves, by using a tube, 
 about 100 yards distant from the building, 
 having a funnel turning to the wind by a 
 vane on the top of it, for supplying the air 
 to the stove, (somewhat as ah air-sad is used 
 on ship-board,) and another on the budding, 
 turning in a contrary direction, for carrying 
 off the-air. This apparatus greatly increases 
 the current of air over the stove; and it 
 was not only found, even during the last 
 severe winter, (1814,) to heat the budding 
 (the Infirmary of Derby) quite sufficiently, 
 but it serves,at the sametime,to ventdatethe 
 whole house. In summer, when, of course, 
 there is no fire made in the stove, the air 
 being, in its subterranean passage, cooled, 
 serves to temperate the air of the different 
 apartments. This subten'anean channel, 
 from its depth below the surface, is so near 
 the mean temperature of the earth, that the 
 air of winter is partiady warmed, whdst that 
 of summer is considerably cooled. In the 
 greatest heat of summer, at this place, the 
 temperature of the air is lowered in its pas¬ 
 sage 20“ of Fahrenheit’s scale. 
 
APPENDIX. 
 
 Description of Fig. S, Nos. 1 and 
 324. DDD represents the stove-coakle, 
 made of plate-iron, one-fourth of an inch 
 thick, having the shape of a dome, the sec¬ 
 tions of which in each direction are semi¬ 
 circular. It is open at bottom, and stands 
 upon the brick-work CC, containing the fire¬ 
 place T. At 6 inches distant from the sides 
 of the stove, aU round is the perforated wall 
 EE, 9 inches thick, which is also continued 
 over the dome, arch-wise, from each of the 
 four sides meeting in the centre. This wall 
 is composed of bricks laid with their ends 
 towards the stove, and in each com’se be¬ 
 tween every two bricks, a tube of thin sheet 
 iron is inserted, reaching to within about 
 three-fourths of an inch of the stove, and 
 having about 2 inches hold in the brick¬ 
 work. The bricks of the second course lye 
 over the tubes of the first course, and so on 
 alternately. 
 
 The size of the air-tubes is 21 inches 
 deep, and 2 inches wide by 7 inches long, 
 exclusive of wings cut out of the plate, 
 
330 APPENDIX, 
 
 which being built into the joints of the brick¬ 
 work, serve to steady the tube. They are 
 made of black sheet-iron, aboutjthe thick¬ 
 ness of common tin-plates, with a lapped 
 -joint on the lower side. The hncks for 
 these walls should be 5 inches broad, ,by 
 2; inches, and 9 inches, which will ,leave 
 more space for the air to ascend betvyeen 
 them. Those Tor the arches, should , he 
 made in the form of a wedge, to, a proper 
 radius, 5 inches broad, and 2? inches thjck 
 at the thin end. The tubes are cemepted 
 into the brick-work, by some fine plaster- 
 lime mortar, but care must be taken to drop 
 none into the space //, in laying the Tricks 
 ■or tubes. 
 
 The perforated wall is surrounded. by 
 tlie cold air-flues KK, which are 2 feet 
 ,2 inches wide, and 3 inches high, co,n- 
 .taining a certain number of courses, accord¬ 
 ing to the size of the stove of bricks and 
 tubes, of which height they are covered 
 over, all round by the flag-stones -VV, 6 
 inches thick, and rabbeted in the joints. 
 
APPENDIX, 
 
 331 
 
 ■ The arched dome of the perforated wall 
 will be best explained by the figures. It 
 should have the same number of tubes 
 above the stone division, as the perforated 
 walls below have; because all the air which 
 enters by the tubes, must issue from the 
 tubes above. In forming this dome, after 
 all the sides have been carried up equally 
 to a certain height or inclination, the bricks 
 will require some supports, to prevent then- 
 falling inwards. 
 
 The mortar in which the bricks of the 
 arches are laid, should be pretty stiflT and 
 fine; and, although the arch may sink a 
 little, the tubfs should be kept a little 
 farther from the stove than those in the 
 perpendicular sides. JJ is the Jire-plnce. 
 A slit (m) formed between tlie iron bar (1) 
 and another which is riveted to the lower 
 edge of the stove, forms the exit for the 
 smoke, which descends by it into the flue 
 (L). This slit is about half an inch wide, 
 being a little more in area than all the slits 
 of the fire-grate, The regulating if on bar (1) 
 has a notch at each end, which drops down 
 
APPENDIX. 
 
 332 
 
 upon a projecting piece, riveted to the 
 stove at each end; and, if the slit proves too 
 wide or too narrow, it can be adjusted by 
 altering the notches at the ends of the bar. 
 In the cliimney are a sliding damper, and a 
 door, made to shut very close; the use of 
 the latter is, to put in some lighted paper 
 or straw, to cause a draught in the chimney 
 at first lighting the fire on the grate, which 
 otherwise may not immediately begin to 
 act. 
 
 The Operation of the Stove. 
 
 325. As soon as the fire is lighted, the 
 smoke passes down by the slit (m) to the 
 flue (L), and fi’om thence to the cliimney 
 the stove gradually becomes warm, and 
 heats the air in the space (h) which sur¬ 
 rounds it, and by means of its becoming 
 lighter, the air passes out by the tubes in the 
 perforated arches, and "more air enters by 
 the tubes in the perforated walls, from the 
 cold air-flues, which being conducted by the 
 tubes, close to the sides of the stove, blows 
 against it like a bellows, and becomes warm 
 in its turn, and ascends as before; but it 
 
APPENDIX. 
 
 cannot pass out by the tubes in the dome, 
 without again coming into contact with the 
 hot stove, which farther increases its heat; 
 and at the same time these ciuTents of air 
 serve to prevent the stove from becoming 
 too hot, if the fire is properly regulated. 
 
 Air-chimneys should be made in each 
 apartment, to let the air out of each story, 
 otherwise the hot air may not readily enter. 
 They may be made of wood, and should 
 each have a turning valve, which should 
 always be fully opened before any fire is 
 made in the stove. 
 
 The smoke-slit (m) will be apt to choke 
 with, soot, which must be removed fi'om 
 time to time. This may be done by draw¬ 
 ing along it a crooked poker, having a point 
 downwards fitted to the slit. 
 
 The thin iron ceiling is shown in the ver¬ 
 tical Section. On the under edge of the 
 joists should be knobs; the use of which is, 
 in some degree, to protect them from the 
 heat, and by that means to lessen their ex- 
 
APtEiJbiXi 
 
 pansibn and contraction^ To these knobs 
 are screwed two sets of thin iron bars, 
 three-eighths by two inches, wliich embrace 
 between them the edges of the thin iron 
 plates which compose the ceiling, and 
 which should meet edge to edge between 
 the bars, with notches in them to free the 
 screws. 
 
 The plates may be simply laid over one 
 another two inches, where they meet at 
 their ends. The holes in the thin bars 
 must be made easy for the screws, that they 
 may be allowed to expand, and they must 
 not touch each other, where they meet at 
 the ends, for the same reason. The ends 
 of the joists must have a plate of iron laid 
 upon the wall under them. When the 
 joists are laid, and the ceiling screwed up 
 to them, and the joists made good^ the 
 whole is filled with ashes about nine inches 
 deep. These ashes should be from house- 
 fires, and sifted through a fire-sieve. 
 
 The air-chamber (Y) serves to conduct 
 the cold air from the door at which it enters 
 
APPENDIX. 
 
 335 
 
 to the cold air-flues by means of the open¬ 
 ings (aa). 
 
 Great care must be taken, in building 
 these flues and their arches, that they may 
 be perfectly smoke-tight, especially where 
 they pass under the cold air-flues 
 
 * On German and Russian Stoves, see Encyclopedia Britannica, article 
 ’Pneumatics and Stove. 
 
APPENDIX. 
 
 FARTHER DETAILS RESPECTING THE HEATING OF 
 PITKELLONT HOUSE. (ScO Art. 207.) 
 
 326. The following letter from Mr. John 
 M'Naught*, who executed the apparatus, 
 came to hand too late for insertion in its 
 proper place. 
 
 Paisley, March 22c?, 1815. 
 
 I)ear Sir, 
 
 (Extract)—“ The steam-apparatus 
 at PitkeUony house, was put up in October, 
 1811. There had been a boiler in one of the 
 out-houses, for the purpose of steaming 
 potatoes for feeding cattle. As Mr. Adam 
 wished to heat the dweUing-house from the 
 same boiler, a copper pipe was conveyed 
 from the boiler along the lobby, and from 
 that pipe took branches into the adjoining 
 rooms. Tlie heaters were made pretty 
 much in the form of a Rumford chimney 
 without the grate, the front and backs were 
 cast in separate pieces, and joined together 
 with iron cement; the under part projected 
 towards the floor, in the form of an ogee, 
 covering part of the hearth, for the purpose 
 of warming a person’s feet, and also of ex- 
 
 • Formerly of Johnston, now of Paisley. 
 
APPENDIX. 
 
 ■ 337 
 
 tending tlie heated surface, as much as pos¬ 
 sible, on the lower part of the room; the 
 chimney being filled up in the throat, and 
 plastered over, allowed none of the warm air 
 to escape in that direction; the steam was 
 taken into one of the corners of the heater, 
 and a pipe taken from the opposite side, 
 connected it with the next heater, and so 
 on through three rooms in the under flat. 
 The steam, after expelling the air out of the 
 first heater, proceeded to the next; in like 
 manner, thi’ough the whole; and a pipe was 
 tak^n through the wall and put into a box, 
 which being inverted into a gravelly soil 
 and covered over, the water easily found 
 its way without any appearance of steam. 
 The stair-case was heated with a large cast- 
 iron pillar, and a pipe taken from the top, 
 heated, a room up stairs; being a small 
 pipe, it was pretty well concealed below the 
 steps of the stair, and afterwards by the 
 moulding above the floor, and the con¬ 
 densed water carried through the wall, and 
 into the gravelly soil, as the others.—I am, 
 . “ Dear Sir, 
 
 “ Your most obed'- Serv''- 
 “JOHN M‘NAUGHT.” 
 
338 
 
 APPEIfDlX. 
 
 ACCOUNT OF THE LIJIE-KILNS AT CLOSEBURN, 
 DOMFRIES-SHIRE. 
 
 327. The use of lime in building, as well 
 as in agricultiure, is too obvious to require 
 proof, and every improvement in the mode 
 of burning it, whether respecting the qua¬ 
 lity of the Ihne, or the economy of fuel, 
 and stm more when it embraces both, these 
 advantages becomes an object of national 
 importance. 
 
 In the Valley of Closeburn, on the 
 river Nith, there is a body of excellent 
 lime^stone, which is wrought op a very ex¬ 
 tensive scale by the proprietor, Mr. Mon- 
 teath. It makes an ample return for the 
 labour bestowed; and he has been at much 
 pains to improve the lime-works. Besides 
 his own unwearied labour and experience 
 at home, he has visited every lime-work of 
 reputation in the island, and has selected 
 and combined every thing that appeared 
 to be advantageous, while he has made 
 several improvements of his own. Tlie re- 
 sidt has been, that his kihis are probably 
 the best in the island. 
 
APPENDIX; . 339 
 
 Instead of the wide and shallow circular 
 kiln, common in the country, Mr. Menteath 
 has found much advantage from making the 
 kUns elliptical and deep. So much with 
 regard to the form of the kilns. 
 
 Mr.' Menteath has lately added some parts 
 to it, which are found of most important use. 
 
 The first is a kind of roof or cover. The 
 want' of some contrivance to protect kilns 
 in stormy weather has long been felt j and 
 various attempts have been made to supply 
 this deficiency. Hitherto, we believe, no 
 covering has been found to answer so iveU 
 as that used at'Cldseburn; and which is re¬ 
 presented in the annexed sketch. 
 
 The next addition, is, that of having 
 castdron doors below at the opening, where , 
 the kiln is drawn. 
 
 There is a grating, through which the 
 ashes fall while drawing the kiln, which 
 makes that operation a much less disagree¬ 
 able employment than formerly. Thp 
 U u 
 
340 
 
 APPENDIX. 
 
 ashes and small lime thus separated, are 
 excellent for agricultural purposes. 
 
 There is often a great loss of fuel from 
 allowing lime-kilns to cool, when there is 
 no demand; but in those of Mr. Menteath, 
 when there is no demand, aU that is neces¬ 
 sary to be done, is to shut the cast-iron doors 
 aboye, as well as below, and the dampers in 
 the chimneys. The heat is thus preserved, 
 and fuel saved, by keeping the kiln hot, to 
 be ready for use when wanted. 
 
 Fig. 1. Plate IV. is a vertical section 
 through the middle of the kiln, wherein 
 AB is the mouth, into which the lime and 
 coal are thrown. It is elliptical, being about 
 9 feet long, and 4i ivide. The kiln continues 
 of the same width to about 18 feet from 
 Ae bottom, when it begins to taper until 
 it is only 22 inches wide below. 
 
 CD is one of the three openings below, 
 by which the lime is dravm from the kiln. 
 
 DEFG is the arched-way by which the 
 lime is removed when taken from the kiln. 
 
APPENDIX. 
 
 341 
 
 AHIB the roof or cover of the kiln, which 
 is shown on a larger scale in Fig. 2.i Nos. 
 1 , 2 , 3 , 4 . . 
 
 Fig. 2. represents the roof, which con¬ 
 sists of a cast-iron frame, upon which the 
 doors k k k k are hung. These doors are 
 opened for the introduction of the lime and 
 fuel. The frame also serves to support 
 the brick arches LMN, upon which are 
 raised the chimneys o o o; and for carrying 
 off the smoke. 
 
 Fig. 3. is a front view of the arch-way, 
 showing the doors for taking out the lime 
 below. 
 
 P P P the doors from Avhich the larger 
 burned lime-stone is taken. There is a grat¬ 
 ing, a b, Fig. 1. through which the ashes and 
 smaller lime fall, which is removed from 
 time to time, by the doors QQQ. These 
 last doors are kept shut while removing 
 the larger lime-stone from the doors P P P, 
 and the people are thereby prevented from 
 being annoyed by the dust. 
 
APPENDIX. 
 
 342 
 
 .Since, writing the foregoingj ii have been 
 favoured, with the, annexed letter from Mr. 
 Menteath, which wUl serve more fuUj to 
 elucidate the subject. 
 
 “ Closebum-Hall, Nov. Isf, 1813. 
 
 “SlE, 
 
 “I.received your letter of the 
 ^Ith of last month, wishing me to send 
 you some particular account of the covers, 
 which I have placed upon tlie top of my 
 lime-Mlns. As you have the dimensions 
 of the covers, I have only to state my opin¬ 
 ion of their utility in facilitating the burn¬ 
 ing of lime-stone. I conceive the greatest 
 advantage to be derived from them, is m 
 the Autumn and Winter season, when a 
 kiln is not worked for more than eight or 
 ten hours each day, when the fire remains 
 long at the.top of the kiln during .a .great 
 part of the remaining sixteen or eighteen 
 hours of the twenly-four. "ViTien the work¬ 
 men are not working the kiln, the foe, by 
 means of the cover, is prevented from es¬ 
 caping during the cold and stormy weather 
 at this season. It is likewise of much use 
 
APPENDIX. 
 
 343 
 
 in, preventing tlie escape, of heat, in ease of 
 a kiln being allowed to remain unworked for 
 
 a day or two, which frequently happens in 
 our country sales, from an irregular demand 
 for .lime. -I am of opinion, that the covers 
 with chimneys in them, increase the. draught 
 of air, through the kiln, by which-means, a 
 given quantity of lime-stone is calcined in 
 a shorter time; but owing to the prejudices 
 of the tacksman and his workmen, it is dif¬ 
 ficult to get at the truth of any thing. The 
 workmen allow, that, owing to the .covers, 
 they put a less quantity of coal into the kiln 
 in the evening, in the winter season, than 
 they would otherwise do, if the kilns had not 
 tops; and also .upon Saturday night, and 
 Monday morning, when an open-topped 
 hiln requires additional coal to make .up 
 fordhe greater loss, or escape, of heat than 
 goes off from a covered kiln. When yon 
 were here, I mentioned to you my having 
 fixed doors to the eyes of the kilns, which 
 are useful, if it be necessary to allow a kiln 
 to stand unworked, (which is frequently 
 necessmy for the reasons I have above 
 mentioned,) by preventing .the lime from 
 
APPENDIX. 
 
 344 
 
 slacking at the bottom; and the doors have 
 the effect of stopping the escape of the heat 
 at the top. 
 
 “ I last year increased the height of my 
 kilns from 24 feet to 30 and 32 feet, which, 
 I am of opinion, has had a tendency to save 
 fuel in the calcination of the lime-stone; but 
 I was disappointed in my expectation of 
 drawing out a greater quantity of burned 
 stone each day, than I was accustomed to 
 do, when the kilns did not exceed 24 feet 
 in height. 
 
 “The dimensions of my kilns are now 
 about 10 feet long at bottom, 22 inches 
 wide, and 20 feet high. After spreading 
 gradudly from the bottom, the width is Ai 
 feet, and the remainder ten or twelve feet. 
 The sides of the kiln are perpendicular, and 
 of course, 4i feet wide at top. My Tacks¬ 
 man thinks that he can burn lime in a nar¬ 
 row kiln of those dimensions, with a less 
 quantity of coal than is commonly used in 
 long circular kilns. I think a circular kiln 
 of not more than 5 feet in diameter, and 
 
APPENDIX. 
 
 345 
 
 30 feet high, burns lime with as small a 
 quantity of coal, as the long narrow OVal 
 kiln; hut the objection to it is, the small 
 quantity of burned lime it produces every 
 day.—I am, 
 
 “ SiK, 
 
 “ Yours respectfully, 
 
 « C. G. S. MENTEATH.” 
 
 Since the foregoing was written, Mr. 
 Menteath has suggested several improve¬ 
 ments on the covers of the kilns, particu¬ 
 larly that of using doors composed of fire¬ 
 bricks, or of fire-tiles, in iron frames, and 
 suspended by chains, similar to those of an 
 air-furnace for melting iron. 
 
 I am informed that many fatal accidents 
 have happened to ships, owing to the light 
 arising from open lime-kilns. The seamen, 
 in dark and stormy weather, mistaking them 
 for light-houses. In such situations, those 
 covers to lime-kilns might be the means 
 not only of securing property, but also of 
 preserving lives. 
 
346 
 
 GAS-LIGHTS. ... 
 
 328. Since Art. 58. was printed, I have 
 read the “ Speeches of H. Brougham, be¬ 
 fore the Committee of the House of Com¬ 
 mons, in opposition to the Gas-light and 
 Coke Compan}’^,” where he states many 
 curious and important facts; two of which 
 it will not be improper here to mention. 
 1st, That six pounds of coal produces light 
 equal to one pound of tallow^ 2d,, That; the 
 London Fire Company * offered’ to insure 
 the works of Messrs. Phillips & Lee, after 
 they were lighted by the coal-gas, at one- 
 half the former premiums 
 
 The coal-gas gives a peculiarly softj clear, 
 and steady light. It has an advantage over 
 candles and oil-lamps, in requiring no. snuff¬ 
 ing or trimming;; and;* therefore, avoiding 
 one source of danger from fire,; to which 
 cotton-iiiills’are peculiarly exposed. A de-i 
 scription. df a -^s-light apparatus, on the 
 large - scale, is given'by Mr. Tj Clegg, , in 
 the Phil. Jdum. voL 'XXIII. p. 86. He es¬ 
 timates the cost of a complete apparatus, 
 
APPENDIX. 
 
 . 347 
 
 capable of supporting forty lamps for four 
 hours, each lamp affording light equal to 
 ten candles, of eight in the pound, to be 
 about 250?. * 
 
 Mr. B. Cook, of Birmingham, has given 
 the results, of his experience in the employ¬ 
 ment of coal-gas-light, in the Phil. Journ. 
 voL XXL p. 293. Among other advan¬ 
 tages, it is particularly convenient for that 
 hind of soldering which is commonly per¬ 
 formed with the oil-lamp, for the gas-light 
 gives a sharper flame, and is also ready at 
 the instant; while, with oil and cotton, the 
 workman is always obliged to wait for his 
 lamp being sufficiently kindled to do his 
 work f. 
 
 For several years, coal-gas has been more 
 or less employed for lighting the streets of 
 London; but last winter its use was greatlj'^ 
 extended. Westminster Bridge was, for the 
 first time, illuminated with gas, and made 
 a most brilliant and splendid appearance. 
 
 * For lighting large cotton-mills, one guinea for each cockspui-light 
 has been estimated as suSicieiit to erect tliu whole apparatus. 
 
 f See Appendix to Aiken's Dictionary of Chemistry, p. 93. 
 
 X X 
 
APPENDIX. 
 
 348 
 
 Both Houses of Parliament, and several 
 of the streets in their vicinity, are now 
 lighted by gas *. 
 
 Nearly the entire range of shops, in the 
 line of streets from Shoreditch Chm-ch, by 
 St. Paul’s, to Westminster Abbey, a length 
 of more than three miles, is either provided 
 with pipes, and lighted by gas, or is in course 
 of preparation f. 
 
 Lord Grey has his house, in Perthshire, 
 lighted in an elegant manner by gas. 
 
 The street all roimd the Admiralty at 
 Petersburgh, being the finest walk in that 
 beautiful city, was lighted, for the first time, 
 by gas, (produced from wood,) in the win¬ 
 ter of 1812—1813. The use of gas-light 
 there was introduced by Messrs. Sobo- 
 leffsky. 
 
 I am indebted to Messrs. Hart, of this 
 place, for the following communication, reT 
 
 ^ Christian Observer, Oct. 1814. 
 f See Monthly Magazine, Nov. 1814. 
 
APPENDIX. 
 
 349 
 
 specting the mode of , lighting their dwell¬ 
 ing-house and bake-house by coal-gas. 
 
 « SiH, 
 
 Glasgow, Vlth March, 1815. 
 
 “ It is rather more than four 
 years since we first attempted to use the 
 gas in lighting our house. Our first plan 
 was a four inch pipe, laid along the back of 
 the common grate, which we charged by 
 the one end, and conveyed off the gas by 
 the other. By taking out a fire tile, we 
 allowed the fire to come upon the pipe, 
 when we wished to make gas. This was a 
 very troublesome method; as our gasometer 
 only contained about one cubic foot, if we 
 applied the fire too soon, we were obliged 
 to light earlier than necessary; if too late, 
 we had to light candles, as the water in the 
 gasometer pit soon got impregnated with 
 tar; when the gasometer was rising, the 
 water evaporating from its sides produced 
 a very disagreeable smell; besides, it was 
 very difficult to keep the luting of the re¬ 
 tort tight, as we then made it pass through 
 about a foot of water, by way of washing it. 
 
S50 
 
 APPENDIX. 
 
 “ As we had, however, a spare piece of 
 ground at the back of the house, we re-r 
 solved to try it on a larger scale, and to get 
 rid of the defects we experienced in the 
 other; we, therefore, built a gasometer 3 
 feet cube, which was as large as the place 
 would contain, otherwise we should have 
 made it much larger. The retort is about 
 2 feet long, by 1 foot in breadth, and 6 
 inches in height, rounded off at the corners, 
 nearly in the form of those used on the great 
 scale, and the furnace likewise built in the 
 same manner. The gas, after leaving the 
 retort, is conveyed into a vessel (immersed 
 in the water of tlie gasometer-pit) about 
 12 inches deep by 10 inches in width, 
 where it deposits its tar. It enters by the 
 top of the vessel, and passes out about 
 half way down, from whence it is conveyed 
 down the side, and along the bottom of 
 the gasometer pit, into a small vessel, about 
 8 inches deep by 6 inches in width. The 
 end of the pipe is immersed about 1 inch 
 below the surface of the water., in this little 
 box, by way of water^valve, to prevent the 
 return of the gas, when the mouth of the 
 
- APPENDIX, 
 
 351 
 
 retort is taken ofF. A pipe from the bottom 
 of this box is raised to the height at which 
 the water should stand, and tlien carried out 
 level; by this means the water can never 
 rise above its proper height, and any tar that- 
 may condense in the pipes, likewise passes' 
 out this way. A pipe rises from the top 
 of this box, above the surface of the water, 
 in the gasometer-pit, by which the gas 
 passes into the gasometer, without any 
 other obstruction. It is, therefore, very 
 easy to keep the mouth of the retort tight; 
 it needs no other luting than a little clayey 
 sand. Another pipe, likewise, descends at 
 the side of this, from the bottom of which 
 passes a smaller pipe through the top of 
 the box into the water, to carry off the tar 
 or water that might condense in it. It then 
 passes along the bottom, and up the side, 
 of the gasometer-pit, to convey the gas to 
 the house. .After it enters the house, there 
 is a stopcock to shut off the gas, should any 
 of the pipes be injured. The burners are all 
 furnished with flexible joints, so that they 
 can be turned in any direction wanted. 
 The joints are formed, by fitting a conical 
 
APPENBIX. 
 
 352 
 
 pipe into the end of the stopcock, to which 
 is soldered a circular plate, about one inch 
 diameter, through which a hole is drilled, 
 into the pipe; it has two concentric grooves, 
 upon which are placed two rings of leather, 
 rubbed fiiU of bees-wax and lintseed oil of 
 the consistence of honey. The use of the 
 two concentric grooves, is, to keep the 
 rings of leather in their places. Another 
 plate of the same dimensions, with a hole 
 in it, to which a branch is attached, is fitted 
 upon it with a screw in the centre. The 
 rings of leather keep the plate so far 
 asimder, as to admit a firee passage for the 
 gas between them, at the same time, keep¬ 
 ing the joints tight. By means of these 
 two joints, the branch can be moved in any 
 direction. When the branch is very long, 
 it is hung by a small counterpoise, a slight 
 spring presses on a wire, soldered to the 
 end of the conical pipe, to hold it steady 
 when the branch is moved up or down. 
 Some;of these joints we have used for three 
 years, without requiring to be taken asunder 
 or repaired. By means of these circular 
 joints, we have a lustre suspended from 
 
APPENDIX. 
 
 353 
 
 the roof; the upper joint is formed of a 
 piece of leather sewed round a spiral wire, 
 and rubbed full of the wax and oil. We use 
 only one erect flame on each burner, as it 
 seems to give more light when erect, than 
 when inclined, as may be seen by raising 
 or depressing one of the branches, or in 
 what is commonly called the cockspur light. 
 By shutting oflT one of the side flames, and 
 trying whether the vertical or inclined 
 flame gives the deeper shadow, the erect 
 flame will be found to give the deeper 
 shadow, both apertures being equal. The 
 cockspur burner must be well formed, 
 otherwise, the horizontal flame deteriorat¬ 
 ing the air, will cause the under part of the 
 vertical flame to appear of a reddish colour, 
 greatly impairing the intensity of its light. 
 
 “ Fig. 1. No. L is an oblique view of the 
 retort and gasometer. A, the retort, as built 
 in the furnace; B, the pipe by which the gas 
 is conveyed to the condenser; C, the con¬ 
 denser; E, the water-valve; F, the pipe to 
 convey the waste water into a common- 
 sewer; G G, the pipe by which the gas is 
 
354 
 
 APPENDIX. 
 
 conveyed into the house; H, a small pump 
 to empty the condenser; I, the gasometer. 
 
 “ Fig. 1. No. 2. is apian of the gasometer, 
 in which the same letters refer to the same 
 parts as Fig. 1. No. 1. . 
 
 “Fig. 2. Conical and circular joint. G, 
 the circular joint; D, the conical joint; 111, 
 rings of leather; Bj the end of the stop-cock; 
 E, the branch. 
 
 “ Fig. 3i The manner of suspending 
 a lustre. KKK, circular brass joints; L, 
 joints formed of spiral wire, covered with 
 leather. 
 
 “ Fig. 4:. The flexible branch. ' 
 
 “ It takes from twelve to fourteen pounds 
 of coal to charge the retort. This (if the 
 coal be good) wiU produce rather more 
 light than two pounds of candles. The 
 coke we esteem of more value than the 
 coal, before the gas was extracted. The 
 only loss, therefore, is in the fuel used in 
 
APPENDIX. 355 
 
 the furnace to heat the retort. As our re¬ 
 tort is only heated once a-week, upon an 
 average^ it requires rather more fuel to pro¬ 
 duce the same quantity of gas, than if the 
 furnace was always kept hot. We find, 
 however, from fourteen to twenty pounds 
 of coal always sufficient to extract the gas 
 for that night, and to leave the gasometer 
 full, which is sufficient for the rest of the 
 week—^We remain, 
 
 « SiK, 
 
 “ Your most obed*- Serv*"' 
 “J, & R. HART.” 
 
356 
 
 ABPENDIX. 
 
 ON THE FURNACES AND CHIMNEYS u'SED:EOR RAPID 
 
 DISTnXATION, IN-TBffi p^STILLEREES IN . SCOT¬ 
 LAND. : 
 
 329. The rapidity of distillation in the 
 Scotch; distilleries has been so great as to 
 appear incredible to those wlio have not 
 witnessed the process. ^ A still of 80 gah 
 Ions was filled with- cold liquor ; that 
 liquor was heated, arid completely distilled 
 ofij and the still again emptied and ready 
 for a new operation, in. the astonishingly 
 short space of 3 to 3" minutes, and those 
 of 44 gallons in migutes. A change 
 having taken place in the Excise laws, 
 it was suggested to me by some gen¬ 
 tlemen, interested in chemical pursuits 
 upon a very extensive scale, that it might 
 be of great practical utility to collect, ar¬ 
 range, and record the facts relative to the 
 construction and dimensions of the furnaces 
 producing those surprising elFscts, while 
 they could be obtained; otherwise, fi’om the 
 changes in the laws above alluded to, the 
 results of many important experiments 
 might, in a short time, be entirely and 
 
APPENDIX. S5% 
 
 irrecoverably lost to the public. For these 
 reasons, I now offer the following result of 
 my inquiries on that subject, which I be¬ 
 lieve to be accurate, and hope will be ac¬ 
 ceptable to all who are interested in the 
 economy of fuel and the management of 
 heat,. 
 
 The stills, in their most improved state, 
 were made to hold from 44 to 80 gallons. 
 They were wide and very shallow. Those 
 of 44 gallons were about 44 inches diameter, 
 and only about 5 inches deep. Those of 80 
 gallons were from 52 to 54 inches diameter, 
 and about 8 inches deep. 
 
 Those stills, perfectly flat in the bottom, 
 and about three-eighths of an inch thick, 
 were. supported by resting an inch and a 
 half on the, brick-work, all round the bilge. 
 
 The furnace, which was quite level, was 
 placed at the distance of 15 inches below 
 the bottom.. • The inner end of the grating 
 bars was placed 15 inches within a line, 
 falling vertically from the part of support 
 of the bilge of the still. The bars were in 
 
APPENDIX. 
 
 358 
 
 two lengths; the inner length was 21 inches, 
 the outer, 30 inches, supported by a cross 
 bar between them, 4 inches square. In 
 front of the, bars was a dumb-plate, 10 
 inches broad. The bottom of the ash-pit 
 was 3 feet below the grating-bars, and on 
 a level with the floor of the distillery. 
 
 For the larger stiUs,' the grating-bars oc¬ 
 cupied-4 feet in width; for the lesser, 3 feet 
 6 inchesi The bars were 2 inches thick, 
 3 inches deep, and three-fourths of an inch 
 apart The brick-work extended 21 inches 
 beyond the dumb-plate, and was 4 feet wide, 
 and 4 inches higher outside than at the 
 bilge of the stiU. The furnace-doors were 
 30 inches wide. 
 
 The coal generally used at Glasgow, for 
 the purpose of rapid distillation, is the best 
 large flaming coal, from the Monkland col- 
 
 The bottom of the furnace, beyond the 
 grating-bars, was lined with fire-brick, 9 
 inches deep, and passed level backward 
 into the chimney. 
 
APPENDIX. 
 
 359 
 
 The chimney was 60 feet high, 4 feet 
 square within from top to bottom, and con¬ 
 sisted of a double wall. The inner wall, of 
 fire-bricks, was 9 inches thick. The outer 
 wall Was placed at 3 inches distance on all 
 sides: froni the inner wall, and the space is 
 left open at top. The outer wall was 18 
 inches thick at bottom, battering regularly 
 on the outside, until reduced to 9 inches at 
 top. -The two walls were tied together, at 
 certain distances, by long fire-bricks. 
 
 The still was placed at 3 feet distance 
 from the outside of the chimney, and a flue 
 3 feet wide and 2 feet li inches high, where 
 it entered the chimney, formed the con¬ 
 nection with the furnace. The whole was 
 lined with 9 inches of fire-brick. 
 
 The above dimensions, with the excep¬ 
 tions mentioned, served all sizes of stills 
 used. - 
 
 Various dimensions of chimneys were 
 tried, but those specified were found to 
 combine most advantages. 
 
APirENPIX. 
 
 When only 36 to , 40 feet high, the 
 draught was not sufficient . When higher 
 than 60 feet, the, flame did not act. properly, 
 and burned the bottom of the stiU. When 
 less, than 4 feet square within, it did not 
 take away the flame sufficiently quick. 
 When 4i feet square, the draught was too 
 great, and the flame burned the bottom of 
 the still. 
 
 For a long time, the walls of the chim¬ 
 neys were built solid, and much trouble 
 w^ experienced from the chimneys giving 
 way, by the intensity of the heat; but an 
 effectual remedy w^ found by leaving the 
 space of 3 inches, as aL;eady described, 
 between the inner wall of fire-brick and the 
 outer waU, composed of common bricks. 
 The walls being thus, in a great measure, 
 unconnected, not only gave liberty for the un¬ 
 equal expansion of the parts, but also saved 
 heat by lessening their conducting power 
 
 * lllie fizr^ing relates to distilleries in thdr most improved state, 
 
 Jo the year 1815. In the “ Report of the Committee of the House of 
 
 Commons,-on tihe Distilleries of Scotland, for il799,” will be found 
 zmicix CQrioQ5 information on dze subject of distillation. In the same 
 R^ort, xrill be found some infonnation on the use of peat^ as fuel. Dr. 
 Jetfay (Appendis to the Report, p. 436) gives it as his opinion, that a 
 
APPENDIX. 
 
 361 
 
 IMPKOVED BOILERS FOR EVAPORATING LIQUIDS; 
 
 330. Ah important improvement lias 
 lately been introduced at some of the alum- 
 works in Yorkshire, in the boilers for e- 
 vapdrating the alum liquor, by means of 
 which, there ai’ises not only a; great saving 
 of fiiel,^ but the process is much facilitated^ 
 and its rapidity greatly increased. 
 
 The boiler is, as usual, made of leadj but, 
 like those generally used for steam-engines^ 
 is covered with an arch-formed top. For; 
 the purpose of filling and feeding the boiler^; 
 there ik a pipe in the middle of the top 
 
 distiller may distil as fast with peat as with coal; but experiments seem yet 
 wanting to. ascertain the comparative strengft, as fuel, of peat and coal. 
 (See Art J4.) In some parts of Scotland, where coal is dear, peat is used 
 in the lime-kilns, and- answers very well, provided the lime-stone be broken 
 into very small pieces. The largest lump should not weigh more than S lb. 
 It requires, at least, a bulk of peat equal to the bulk of lime in the kiln; 
 but ranch must depehd-6n tire quality of the peat 
 
 Peat as fuel for distilleries and other similar furnaces, wants some of the 
 inconveniences of most kinds of coal. In almost all coal there is matter,- 
 which, by strong heat turns into slag or coarse glass, and adheres to the 
 bars of the grate, thereby interrupting the passage of tile air to the fuel. 
 See Report, p. 434. 
 
 Silversmiths in Scotland smelt silver and gold with peat not because peat 
 raises more heat than coal, but because coal contains gases which injure 
 tliose metals. See Report p. 455. 
 
APPENDIX. 
 
 which reaches nearly to the bottom. The 
 top has some inches of saw-dust over it, to 
 serve in some degree as a non-conductor 
 of heat. 
 
 The process of evaporation is performed 
 by means of a communication between the 
 surface of the liquor and the chimney, 
 (immediately behind the fire,) which having 
 a strong draught, answers the double pur¬ 
 pose of lessening the pressure of the atmos¬ 
 phere, and carrying off the steam as fast as 
 it rises to the surface, and thereby render¬ 
 ing the process much more rapid and eco¬ 
 nomical than it was in the mode formerly 
 in use. 
 
 Another advantage of this mode of evap¬ 
 oration, is, that when the fiimes are dis¬ 
 agreeable or unwholesome, they are carried 
 off, without affecting the salubrity of the 
 air *. 
 
 ♦ See “ Repertory of Arts and Manufactures,'* toL II. p. 37, where a 
 furnace, constructed with a view to the attainment of this object, is de- 
 
APPENDIX. 
 
 363 
 
 This principle is put in practice in the 
 following simple manner. Within the boiler 
 on each side, nearly over the back part of 
 the fire-place, is a pipe of 4 inches bore, 
 having its open mouth a few inches above 
 the surface of the liquid. This pipe descends 
 nearly to the bottoni of the boiler, where it 
 passes out of the side, into a short flue, 
 through which the steam is drawn into the 
 flame of the fire, and thence, of course, 
 into the chimney. 
 
 Does not this mode of evaporation sug¬ 
 gest an important improvement. on the 
 manufacture of common salt, and, indeed, 
 on almost all manufactoes depending upon 
 evaporation of fluids, by means of culinary 
 fire? 
 
ERRATA. 
 
 Page 63, line far wood, charcoal, read wood-charcoal. 
 
 . 173, Iast line,/or Bdidores Arch. Hjdraulique, read Architecture 
 
 Hydraulique, par M,-Belidore, tom. iii. 
 
 158,/r Keaumenr, read Keaumur. 
 
 174, lines 4, 7, 9, and 11,/ir &cet read faucetT 
 
 ITS, — S and 16, for facet read faucet . 
 
 ISl, — 19, for the valve a, read the valve e. 
 
 182, — 4, 5, and 14, for guage-coct read gauge-cock. 
 
 192, — 15, for new read next 
 223, — 22, for 112 read 212. 
 
 295,_ 8,10, and 20, for Netherly read Netherby House. 
 
 544, 15 —19 ,/r “Thedimensions,” &C. read “The dimensions 
 
 of my kilns are now 9 or 10 feet long at bottom, and 22 
 inches wide, and about 50 feet high. After spreading 
 gradually fiom the bottom, they arc 4j feet wide, at 18 
 or 20 feet ftom the bottom, and the remaiiMg 10 or 12 
 feet is perpendicidar at the same width, and, of course, 4f 
 feet wide at top. 
 
 A44, — 23, for long read large. 
 
JJVB JE X 
 
 AmucMON, - - 103,107 
 
 Aberdeen, "West Church, 297 
 
 Accum, Mr. - - • - 72 
 
 Adelphi cotton-mill, - 165, 247 
 Air, - - - - 103 
 
 brcatlied by the human species, SO 
 circulation of, - - 217 
 
 condensed, - - - 129 
 
 pump, - - - 131 
 
 rarefaction of, - - 232 
 
 rarefied, - - - 129 
 
 stratum of, - - - 123 
 
 Air chimney, - - - 277 
 
 Alcohol, - - - - 133 
 
 Anderston tambouring-mill, 247 
 
 Annales de Chenue, - - 267 
 
 Apparatus, feeding, - - 235 
 
 Arrangement, - 187, 190, 192 
 
 Arrangement of tlie pipes, - 986 
 
 Atmosphere, defended from, 236 
 external, - - 120 
 
 Attrition, - - . - 155 
 
 Barometer, - - - 22S 
 
 standing, - - 9 
 
 Bars, - - - - 279 
 
 Baths, Mr. Harley’s, - - 302 
 
 Black, Dr. 11, 43, 78, 141, 143 
 Block-printing shops, 208,218 
 Blow-pipe, ... 154 
 
 Bodies, - . - - 55 
 
 coloured, - 56 
 
 lieated, - . .102 
 
 soUd ice, - . 53 
 
 their condensation, - S3 
 
 tlieir specific heats, . S3 
 
 Boerhaavc, Dr. - - - 11 
 
 Boiler, .... 241 
 
 descriptfon of, - .179 
 
 surface exposed to fire, 81 
 for generadng steam, 179 
 
 proportionate size of, 160 
 
 Boilers, ... 280 
 
 Boiling, ... 1,31, 137 
 during the day, . 216 
 
 point, . 8, 9, 10, 134 
 
 Branning, dyeing, &c. - . 218 
 
 Brass, expansion of, . 168 
 
 Breweries, ... 68 
 
 Brick flues, ... 244 
 
 conductors, , . .88 
 
 work, . . 196, 238 
 
 Bro^^Mr.^’ - - - 232 
 
 Brook Taylor, Dr. . . 12 
 
 Building, .... 245 
 nature of, - . 163 
 
 Bush Farm, ... 295 
 Butterly Iron-Works, . 177 
 
 Calomclcr, - 
 Caloric, - 
 
 of die term, . 
 Candle, wax, 
 
 cylindiic.al, 
 internal, - 
 p.ainted, 
 tinned iron, - 
 Carbonic acid gas. 
 Cast-iron, 
 
 Catrine, 
 
 Centigrade, - 
 Chaptal’s Chemistry, 
 
 - 208 
 - 91 
 
 98 
 
 279, 285 
 
 77, 80 
 
INDEX- 
 
 SUk-conductor, - « - 
 
 Silver, quick, boils, - - 1 
 
 Sliding spy-glass, - - 2 
 
 Solid, . _ - - 
 
 Solii, their expansion, 
 
 to measure tlieir expan- 
 
 Specifically lighter, - - 1 
 
 Spigot and faucet join^ 1V4,214,2 
 pipes, - . 1 
 
 Steam, 78, 135, 136, 137, 241, 243 
 
 black-bull inn heated by, 197 
 
 conductor,^ 
 
 SlTBUck, 
 
 drying and heating by, 203 
 drjing dyed and bleached 
 
 dwclUnghousesheatedby, 
 effect of, 
 
 engine^ - ■ - 
 
 general abstract of build¬ 
 ings warmed by, - 
 its combination, 
 
 substance and su 
 face of, - 
 arrangement of, 168,171 
 
 - 95, 240, 242 i 
 
 comparative of fuels, 
 of liquid?, their expan¬ 
 sion in bulks, , 
 its explanation. 
 
 21 
 
 of boiling points, > 132 
 
 of conductors, - - 89 
 
 of expansion of air, .148 
 
 liquids, 149 
 for 180 degrees of 
 
 Fahrenheit, 
 
 , 149 
 
 of thermometers, - 25 
 
 relative to BIr. Dalton’s, 20 
 Tar, oily, - - - - 77 
 
 Toniporntiiro 18,57,102,194,140,151 
 
 Centigrade, - 9 
 differential, - 99 
 Fahrenheiti?, 9,13,225 
 
 mercurial, 14,19,97 
 Murray’s, - 10 
 
 Reaumur’s, - lo ’ 
 
 IVedgewood’s, 152 
 Tbimble joint, . 174,214 
 
 Thin copper drums, - - 169 
 
 Thin musli,us dried, - 211 
 
 Tliomson’s Annals of Philoso¬ 
 phy, - - - 272,275 
 
 Tin, expansion of, . - 169 
 
 Tin-plate, - - . 154 
 
INDEX. 
 
 V^KJur, elastic^ ; - iSS.j Chimneys Belfast, 
 
 Vdod^,'^ " . “ " ■ 102 Chinmey-sw^ers, 
 
 -of radiant heat, - 94 Church, Christy -