I MR. WEALE’S NEW SERIES OF RUDIMENTARY WORKS FOR BEGINNERS. Mr. We ale has prepared for publication, in a neat and convenient size, a series of original and useful Volumes, by the most esteemed miters, forming a Rudimentary Course for the easy comprehension of the leading principles of various Sciences. . ,. , _ . . , It has been remarked, that “ those who are in the ship of Science ought to remember that the disciples cannot arrive without the aid of boats.” Popular Treatises are to Science what boats are to large ships: they assist people in getting aboard. But as no one would trust himself to a weak or inefficient boat, so no one ought to begin the study of Science with an im¬ perfect guide. 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Rudimentary Chemistry, by Professor Fownes, F.R.S., &c., third edition, and on Agricultural Chemistry, for the use of Farmers Is. ___ Natural Philosophy, by Charles Tomlinson .... Is. ___Geology, by Lieut.-Col. Portlock, R.K., F.R.S., F.G.S., &c. Is. __ Mineralogy, by D. Varley, Author of ‘ Conversations on Mine- _-_ ralogy,’ 2nd edit. vol. i. ]s - vol. ii. ' * — Mechanics, by Charles Tomlinson . . _ Electricity, by Sir William Snow Harris, F.R.S., &c. r--- 2 MR. weale’s new series of rudimentary works. CONTINUED SERIES OF RUDIMENTARY WORKS FOR BEGINNERS. Price. Rudimentary Pneumatics, by Charles Tomlinson ...... - Civil Engineering, by Henry Law, C.E. vol. i. . . . -vol. ii. . , . -Architecture (Orders), by W. H. Leeds, Esq. . . -Ditto (Styles—their several examples), by T. Bury, Architect, F.I.B.A. 1 . 9 . Is. IS. Is. IS. — Principles of Design in Architecture, by E. Lacy Garbett, Architect, vol. i..Is. -vol. ii. is . — Perspective, by G. 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( Written specially for this Rudimentary Series.) .Is. Art of Blasting Rocks and Quarrying, and on Stone, by Major-Gen. Sir John Burgoyne, K.C.B., R.E., &c., &c. . Is. Dictionary of Terms used by Architects, Builders, Civil and Mechanical Engineers, Surveyors, Artists, Ship-builders, &c. &c. vol. i... Is. -vol. ii.. . Is. -vol. iii.. Is. -vol. iv. . . .. , is. SERIES OF RUDIMENTARY WORKS OF MATHEMATICAL SCIENCE FOR BEGINNERS. The Series of Rudimentary Works for the use of Beginners has rea¬ lized the anticipated success from that portion of the public who seek the attainment of those objects of Science which belong to the business of life, and the highest and most useful subjects in the Elements of Art and Science. Pursuing the same path, to render further aid to public in¬ struction, and to direct the attention of the Heads and Principals of the several Colleges and Schools of the United Kingdom, and the Royal Military Academies, to these serial works, it is intended to publish an Elementary Course of Mathematics for the use of Beginners, at Is. each volume. It has been observed by Bonnycastle, in the Preface to his admirable Elementary Work on Algebra, that “ Books of Rudiments, concisely written, MR. WEALDS NEW SERIES OF RUDIMENTARY WORKS. complete.” successfully and methodically, the most selected, under the abl f e J ag c olle! re London, who, with the co-opera- S“fol£ng ^e, Wi/pfoduce . set of bools that will be found efficient both for public and self-instruction. W. S. B. WOOLHOUSE, F.R.A.S., Actuary of the National Loan Fund, Author of several Scientific Works. „j Author of several Professional Works. Hj^DLi'oiib dnUhmetieaf and r &K 0 ihl U M 8 dheniatical Maater, King". 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WEALE S NEW SERIES OF RUDIMENTARY WORKS Rudimentary Treatise on Hydraulic Engineering, and on Tunnellin^ through various kinds of Strata, with Plates, forming a third , vo ; ° f . th « Engineering (and completing that subject), pub- lished in the First Series ...... 1 - Locomotive Engines, describing them on the ailwavs for thpir covin™! J .i 1 . . Is. . . "‘'vinuoj ucoujuiuR inem on the various Railways for their several purposes, and their duty and efficiency, by J. Sewell, L.E. 3 n „,i r ~ Ma ? IN t> E „ 1 ? ginbs and Steam-Boats, for Sailors and Engineers, by R. Murray, C.E. Art of Ship-building, The Elementary Principles’ with Plates, by J. Peake, H. M. Naval Architect . Tiie Practice, Plates, by the’same Masting, Mast-making, and Is. Rigging of Ships Maritime Nations"&c. ^ AILOR ’ s Ska-Books, Flags of a li Also in Preparation, Rudimentary Treatise on Magnetism, by Sir W. S. Harris, F.R.S. vol. i. * -Ditto, the Continuation of the same subject, vol. ii, - Supplement to Ditto, vol. iii. ..." ’ ’ ' “ TIIE Warming and Ventilating of Public and Private Buildings, with Illustrations, by Charles Tomlinson, vol. l. ’ 3 --- Ditto, vol. ii., by the same Akt and Practice of the Surveying of Land, on the Art of Surveying and Levelling for Road-making Rail- way-making, and the Making of Canals, &c., bv T. Baker, C.E.,with Illustrations, vol. i. 3 - Ditto, also the Field Book, vol. ii., by the same ! • Treatise on the Construction of Railways, with nu¬ merous Illustrations, by Rowland Macdonald Stephenson “ on Clocks and Watch-making, with a Chapter on Church Clocks ; with Illustrations, by E. B. Denison, M.A.. Author of two papers on Clock Escapements, in the Cambridge Philosophical Transactions, vol. i. . . , # ° vol. ii. Conchology, &c. (Fossils and Shells)’ vol.’i. ! ~ Continuation of the same subject, vol. ii . Elements of Music, with Plates of Examples, vol i Practice of Music, with Plates of Examples, vol. ii. Instruction on the Piano-forte ... Descriptive Geometry, Applied to Ship-building (text), by J. F. Heather, M.A. . • • ; . ° v J , v, TT 7~T At ' as of Plates illustrative fdrawing- book), oblong 4to, by J. Peake, H. M. Naval Architect . . Applied to Architecture (text), by J. F. Heather, M.A. book), oblong 4 to, by J. F^to?” by J.F. Heather, M.A~ t0 Ch ' U En f? ine ering (text)’, - Atlas of Plates illustrative (drawing- book), oblong 4to, by J. F. Heather, M.A. . ... 7 ) ~ ~ ; Applied to Mechanical Engineering (text), by J. F. Heather, M.A. b . ° j TT ~ : Atlas of Plates illustrative (drawing- book), oblong 4to, by J. F. Heather, M.A. . . . “ wH^bours and Coast Engineering, by Thomas Stevenson, C.E., with Illustrations . t ■ Ditto, the Continuation of the same subject, vol’. ii. '. iREATiSEJ ON MlLL AND FACTORY ARCHITECTURE, by T. Fairbairn, C.E., with Illustrations . . . ... Ditto, the Continuation of the same subject, vol'. ii. ! and Practical Treatise on Boilers, for all kinds of oteam Engines, by Robert Armstrong, with wood-cuts . 16. A RUDIMENTARY TREATISE ON THE MANUFACTURE OF BRICKS AND TILES; CONTAINING AN OUTLINE OF THE PRINCIPLES OF BRICKMAKING, AND DETAILED ACCOUNTS OF THE VARIOUS PROCESSES EMPLOYED IN THE MAKING OF BRICKS AND TILES IN DIFFERENT PARTS OF ENGLAND. PART I. CONTAINING Introduction. Chap. I_General Principles of the Ma¬ nufacture of Bricks and Tiles. Chap.Jl.—On the Manufactureof Bricks and Tiles.in Hollajick • ^ • Chap. III.—Brickmaking, as practised at Nottingham. Chap. IV.—Brickmaking, as practised in Ml the Staffordshire Potteries. ILLUSTRATED wiTp sg ENQBAYWS QN wood. BY EDWARD DOBSON, ASSOC. I.C.E. AND M.B.I.B.A. AUTHOR OF “ THE RAILWAYS OF BELGIUM,” ETC. ETC. LONDON; JOHN WEALE, 59, HIGH HOLBORN. 1850. C €>f^s, TP D ^ IS 7 LONDON : GEORGE WOODFALL AND SON. ANGEL COURT, BKINNER STREET. THE GETTY CENTER LltSrtAHY PREFACE. The preparation of this little work has necessarily ex¬ tended over a considerable period of time, and, although our limits preclude anything like an attempt at a com¬ plete view of the principles and practice of Brick¬ making, it will be found to contain much practical information which has never yet been published, and descriptions of processes which are little known be¬ yond the localities where they are practised. The whole of the illustrations have been drawn expressly for the Work, and the descriptions of tools and pro¬ cesses have been written from personal observation, no dependance having been placed on verbal descrip¬ tion, even by experienced workmen. Working brick- makers are mostly illiterate men, unable to describe correctly their own operations, and still less to explain their meaning. I have therefore considered it necessary to have every process here described carefully watched throughout, either by myself or by some one on whose accuracy of observation I could place dependance. In the course of last autumn I drew up several papers of questions, embracing a variety of points on which it was found difficult to obtain correct information, but which were distributed amongst those of my friends who were likely to have opportunities of ascertaining what was required. Many of these papers in course of time were returned, accompanied by valuable details, and I have to express VI PREFACE. my thanks and obligations to many gentlemen per¬ sonally unknown to me, for the assistance thus af¬ forded. Amongst those from whom I have received valuable assistance during the progress of the work, I may especially mention the names of Mr. Arthur Aikin, Mr. John Lees Brown, of Lichfield, Mr. William Booker, of Nottingham, Mr. Richard Prosser, of Birmingham, and Mr. Frederick Ransome, of Ipswich. Mr. Richard Prosser has kindly contributed a valuable account of the practice of Brickmaking in Stafford¬ shire which will be read with much interest, and it will be worth the reader’s while to compare the processes described in this chapter with those made use of in the neighbourhood of Nottingham, described in Chapter III. The details given in Appendix I. respecting the manu¬ facture of Suffolk bricks were kindly furnished by Mr. Frederick Ransome, to whom I am also indebted for drawings of a Suffolk kiln, which were intended by him as a contribution to the work, but which un¬ fortunately were committed to the post for transmis¬ sion, and never reached their destination. In collecting the information requisite for writing the accounts of Brickmaking and Tilemaking as practised in the neighbourhood of London, I am under great obli¬ gations to Mr. Adams and Mr. Randell, of the Maiden- Lane Tileries, and to Mr. Samuel Pocock, of the Cale¬ donian Fields, Islington, for the kindness with which they afforded me facilities for inspecting and sketching their works, and for the liberal manner in which they furnished me with details of prices and quantities. Although much time and pains have been bestowed upon the work, there is so much difficulty in writing a strictly-accurate account, even of a simple operation, that PREFACE. Vll I cannot hope that it is perfectly free from errors; but I trust that they are only of a trivial nature, and I shall he greatly obliged to any reader who will point out any omissions or mis-statements, that I may be able to cor¬ rect them in a future edition. There has long been a want of rudimentary treatises on the Materials of Construction, published in a cheap form, and written in a simple and practical style, di¬ vested of scientific technicalities, which render such books nearly useless to those by whom they are most needed. I venture to express a hope that this work may be of service in supplying this deficiency with regard to one very important class of building materials. At the same time it must be observed that the science of Brick¬ making is as yet untrodden ground, comparatively little being known of the manner in which different sub¬ stances mutually act upon each other when exposed to furnace heat, or of the relative proportions of silica, alumina, lime, and other usual ingredients of brick- earths, which are best calculated to produce a sound, well¬ shaped brick, of a pleasing colour. All that I have attempted here, therefore, is to give a clear description of the actual manufacture of bricks and tiles, and to explain the leading differences which exist in the manner of conducting the several operations of Brickmaking in various parts of this country. How far I have suc¬ ceeded in this attempt the reader alone can determine. London, 1850 . EDWARD DOBSON. CONTENTS OF PART I. N.B. — The Numbers refer to the Paragraphs and not to the pages. INTRODUCTION. I. Early history of the art would not add to our practical know¬ ledge. II. Burnt brick used in the building of the Tower of Babel; in the walls of Babylon ; both burnt and sun-dried bricks used in ancient Egypt. III. Bricks extensively used by the Romans ; the art of brick¬ making lost at the decline of the Roman Empire ; subsequently revived in the middle ages. V. Brickmaking introduced into England by the Romans ; arrived at great perfection at the time of Henry VIII. : only used for large mansions in the time of Queen Elizabeth. VI. Brick generally introduced as a building material in London after the great tire of 1666; many tine specimens of brickwork still extant, executed at the beginning of the 18th century. VII. Enumeration of the duties successively imposed upon bricks and tiles ; abolition of the distinction between common and dressed bricks, by 2nd and 3rd Viet. c. 24. VIII. The new act a great boon to the public. IX. Bricks used for drainage works exempt from duty; difficulty of defining the extent of the ex¬ emption. X. Number of bricks made yearly in Great Britain. XI. Differences in the processes employed in brickmaking in different parts of England. CHAPTER I. GENERAL PRINCIPLES OF THE MANUFACTURE OF BRICKS AND TILES. I. BRICKS. 1. Classification of the various operations of the brickmaker. preparation of brick-earth. 2. Enumeration of qualities to be aimed at in making bricks. 3. Suc¬ cess depends principally on the selection and preparation of brick-earth. 4. Brick-earths may be divided into three principal classes; viz., pure CONTENTS. IX clays, marls, and loams; few earths fit for brickmaking without some mixture. 5. Alumina the principal ingredient in brick-earth; cracks in drying, after being moulded, and will not stand firing ; necessary to add sand to strong clays, to diminish (their contraction ; lime and sifted ^ breeze used near London for the same purpose. 6. Composition of fire clay. 7. Table, showing the constituents of several infusible earths. 8. Enumeration of principal localities where fire bricks are made ; rela¬ tive cost of Windsor, Welch, and Stourbridge fire bricks. 9. Bricks made of refractory clav, baked rather than burnt. 10. Composition of fusible earths. 11. London bricks not made of clay, but of loams and marls. 12. Bricks may be divided into two classes, baked and burnt ; difficulties in treating the fusible earths. 13. Cutting bricks made from sandy loams, either natural or artificial. 14. Colour depends not on the natural colour of the clay, but upon its chemical composition. 15. Bricks might be made of various colours by the employment of metallic oxides. 16. Floating bricks. 17- Unsoiling. 18. Clay digging and weatherinq. 19. Stones must be picked out by hand ; injurious effect of limestone in the clay. 20. Grinding. 21. Washing. 22. Cutters made of washed earth mixed with sand. 23. Sufficient attention not generally paid to the preparation of brick-earth. TEMPERING. 24. Object of tempering; is effected in various ways; treading, grind¬ ing, pugging- 25. Brickmaking on the Nottingham and Grantham railway. 26. Use of the pug-mill. MOULDING. 27. Slop moulding and pallet moulding. 28. Description _ of slop moulding. 29. Description of pallet moulding. 30. Description of moulding table. 31. Brick moulds, their varieties. 32. Difference m rate of production per stool, according to the process employed. 33. Brickmaking at the South Mimms tunnel. 34. Moulding by ma¬ chinery. 35. Disadvantages of dense bricks. 36. Method invented by Mr. Prosser of moulding in the dry state. 37- Defects of pressed bricks. 38. Difficulties in making moulded bricks, arising from warp¬ ing in the kiln. 39. Dimensions of brick moulds. 40. Bricks made of various shapes in country yards, but not in London. 41. Bricks with hollow beds. 42. Ventilating bricks. DRYING. 43. Slop-moulded bricks dried on flats, and hacked under cover. 44. | Bricks hacked in the open air where brickmaking is conducted on a ! large scale. 45. Clamp bricks hacked at once, and not dried on flats. 46. Recapitulation of differences between slop moulding and pallet moulding. 47. Different clays require different treatment. BURNING. 48. Bricks burnt in clamps and in kilns. 49. Peculiarities of clamp burning. 50. Three classes of kilns. 51 . Management of a kiln. 52. Impossible in a rudimentary treatise to describe all the processes in use. X CONTENTS. II. TILES. 53. Differences in the manufacture of bricks and tiles. 54. Three classes of tiles, viz., paving-tiles, roofing-tiles, and draining-tiles. 55. Business of a tilery includes the making of pottery. 56. Tiles burnt in the country together with bricks ; in London in separate kilns. 57. Draining-tiles principally moulded by machinery. 58. Importance of making drain-tiles a home manufacture. 59. Concluding observations. CHAPTER II. ON THE MANUFACTURE OF BRICKS AND TILES IN HOLLAND, BY HYDE CLARK, C.E. I. BRICKS. Bricks extensively used in Holland for a variety of purposes.—Dutch clinkers made at Moor, two miles from Gouda.—Material for making them is the slime of the river Yssel and of the Haarlem Meer._Tlie sand used is brought from the banks of the river Maes_For Flemish bricks the sand is brought from the river Scheldt.—The slime and sand are mixed, and kneaded together by treading.—Dimensions of paving bricks and Dutch clinks—House bricks and tiles made at Utrecht from brick-earth found in the neighbourhood.—Dimensions of house-bricks. II. BRICK-KILNS. Sometimes made to burn upwards of a million of bricks.—Fire-holes left in the side-walls.—Doorway made in the breadth of the kiln_Sheds erected on each side of the kiln to shelter the fires.—Mode of setting the kiln.—Mode of firing. 8 III. TILES. Varieties of tiles made in Holland.—Clay ground in a pug-mill.— Kneaded by women before moulding—Two moulders, viz., a rough moulder and a finisher.—Tiles dried first in sheds and afterwards in the sun—Moulding of flat paving-tiles—Iron moulds used in Switzerland. IV. TILE-KILNS. Tiles burnt in covered kilns with arched furnaces.—Setting Burn- ing. —Cooling.—Mode of giving a gray colour.—Glazing.—Utrecht the principal seat of the tile manufacture.—Gouda celebrated for pottery and tobacco-pipes. J CONTENTS. XI CHAPTER III. BRICKMAKING AS PRACTISED AT NOTTINGHAM. 1. Peculiarities in manufacture of bricks near Nottingham. 2. Use of brass moulds not confined to Nottingham. 3. Object of crushing the brick-earth between rollers. 4. Advantages and disadvantages of the use of rollers. 5. Description of brickmaking at Nottingham applies, with slight variations, to the practice of the neighbouring counties. 6. Brick-earth from the marls of the new red sandstone; abounds with layers of skerry and veins of gypsum. 7* Colour of Nottingham bricks. 8. Common bricks made without picking the clay. 9. Prepa¬ ration of clay for making front-bricks. 10. Manufacture of rubbers. 11. Clay at Nottingham not generally suited for making roofing tiles. 12. Size of old and modern bricks. GENERAL ARRANGEMENT OF A BRICKWORK. 13. Locality of existing yards. 14. Rental and cost of clay. 15. Ar¬ rangement of buildings. 16. Description of clay-mill. 17- Addition of a second set of rollers a great improvement. 18. Reference to engrav¬ ings of clay-mill. 19. Mode of boxing up the machinery. 20. Duty performed. 21. Length of time a clay-mill will remain in working con¬ dition. 22. Description of Wash-mill. 23. The Pug-mill not used at Nottingham. 24. Moulding sand. 25. Moulding table , description of. 2G. Brick mould , description of. 27* Use of copper moulds confined to small articles. 28. Mould placed on the moulding table and not upon a stock-board. 29. Plane, description of. 30. The Flats, how prepared; size of. 31. The Hovel, description of; sometimes provided with flues. 32. Best bricks dried wholly under cover in flued hovels. 33. The Clapper , description of; use of. 34. Dressing bench and dresser. 35. Machi¬ nery for pressing bricks; points to be attained in making. 36. Machine- pressed bricks cheaper than those dressed by hand. 37- Kiln , detailed description of. 38. Different mode of constructing the walls. 39. Com¬ parison of the two methods. 40. Reference to engravings. 41. Steps to the tops of the kilns. 42. Sizes of kilns. 43. Duration of kilns. PROCESS OF BRICKMAKING. 44. Clay digging. 45. Tempering. 46. Cost of. 47. Moulding , de¬ scription of process. 48. Drying'; laying on flats; hacking. 49. Time that should be allowed for drying. 50. Cost of moulding and drying. 51. Pressed bricks. 52. Polished bricks. 53. Size of brick- moulds. 54. Rate of production. 55. Burning; management of the firing. 56. Cost of fuel. 57. Effect of the fire upon the colour of the bricks. 58. Cost of setting and drawing the kiln. 59. Cost of labour in firing. 60. Enumeration of the varieties of brickware manufactured at Nottingham. CONTENTS. xii COST OF MANUFACTURE. 61. Land and brick-earth; difficulty of estimating rental; cost of clay. 62. Buildings and machinery; difficulty of ascertaining best relative sizes of working floors, hovels, and kilns. 63. Approximate estimate of extent of buildings and plant required for a weekly production of 46.800. 64. Additional buildings required in a yard, where all kinds of brick ware are made. 65. Enumeration of tools required. 66. Labour, how paid for. 67- Summary of cost of production. 68. Relative value of dif¬ ferent qualities of bricks. 69. Reference to illustrations, figs. 1 to 18. CHAPTER IV. BRICKMAKING AS PRACTISED IN THE STAFFORDSHIRE POTTERIES, BY R. PROSSER, C.E. 1. Bricks ; enumeration of kinds of brick manufactured. 2. Drab bricks chiefly used for furnace work. 3. Tiles. 4. Clay. 5. Names of strata. 6. 1 wo examples will be given of the process of brick and tile making. FIRST EXAMPLE—BRICKMAKING. 7 . Buildings and plant. 8. Rates of production. 9. Tempering. 10. Moulding. 11. Drying. 12. Loss of weight whilst drying. \3. Burn¬ ing. 14. Cost of manufacture. 15. Rental. DESCRIPTION OF ILLUSTRATIONS. 16. Clay-mill. 17-Moulding table. 18. Brick mould. 19. The oven or cupola. SECOND EXAMPLE—TILE-MAKING. 20. Enumeration of articles made at Basford. 21. Weathering and tempering. 22. Moulding. 23. Drying. 24. The Set. 25. Quarries and Dust Bricks. 26. Drain-tiles. 27. Tile machines. 28. Firing; detailed description of. 29. Selling prices of different articles. ILLUSTRATIONS. 30. Moulding-bench. 31. Mode of drying tiles. 32. Tile-block and horse. 33. Mode of setting lower part of oven. 34. Mode of setting upper part of oven. 35. Desirability of improving the mode of conduct- of^lays *&^ rmfaCtU1 ' e ° f bliCkS * 3G, ‘^ x l iense °f carriage. 37. Analysis BRICKMAKING ON THE SOUTH STAFFORDSHIRE RAILWAY. 38. Bricks made for this line by Mr. George Brown of Walsall Wood. Material not clay but marl. —Description of strata.—Description of processes employed.—Cost of bricks at the kiln. RUDIMENTS or THE ART OF MAKING BRICKS AND TILES. INTRODUCTION. I. It would be impossible, in a little volume like the present, to enter at any length upon the early history of the Art of Brickmaking, nor would such an investi¬ gation, however interesting in a historical point of view, add much to our practical knowledge of the subject. It is, however, desirable that we should give a few particulars relative to the progress of the manufacture in this country; and we propose at the same time to give a brief sketch of the legal restrictions which have been imposed from time to time upon the mode of conducting the operations of the brickmaker: in doing which we shall have occasion to point out some anoma¬ lies in the present excise duties, which deserve the attentive consideration of the Legislature. II. The use of brick as a building material, both burnt and unburnt, dates from a very early period. Burnt brick is recorded in the Bible to have been used in the erection of the tower of Babel; and we have the part i. u 2 INTRODUCTION. testimony of Herodotus for the fact, which is confirmed by the investigations of travellers, that burnt bricks, made from the clay thrown out of the trench sur¬ rounding the city, were used in building' the walls of the city of Babylon. Sun-dried bricks were extensively used in ancient times, especially in Egypt, where their manufacture was considered a degrading employment, and, as such, formed the principal occupation of the Israelites during their bondage in Egypt after the death of Joseph. Very interesting ancient representations of the pro¬ cesses employed are still in existence, and throw much light on various passages of Scripture. Thus, the pas- ] sage in Psalm lxxxi. 6, “ I removed his shoulder from the l burden; his hands were delivered from the {water) pots,” is strikingly illustrated by pictures still preserved to us, in which labourers are carrying the tempered clay on their shoulders to the moulders, whilst others are engaged in carrying vessels of water to temper the clay. The ; Egyptian sun-dried bricks were made with clay mixed with chopped straw, which was furnished to the Israelites by their Egyptian taskmasters before the application of Moses to Pharaoh on their behalf, after which the ob¬ ligation was laid on them to provide their own straw, which appears to have been a grievous addition to their labour. It would appear from the details given, that the Israelites worked in gangs, under the superin¬ tendence of an overseer of their own nation, who was provided with all necessary tools and materials, and who was personally responsible for the labour of the gangs. ; Burnt bricks were, however, also used in Egypt for river walls and hydraulic works, but, probably, not to any very great extent. It is recorded in 2 Samuel xii. 31, that David put- INTRODUCTION. 3 the children of Ammon under saws, and harrows and axes of iron, and made them pass through the brickkiln: without entering on the question whether the Ammonites were made to labour in the brickfields as the Israelites had themselves previously done during the time of their bondage in Egypt, or whether we are to understand that they were put to death with horrible tortures, as supposed by most commentators, there is a strong presumption that the implements here spoken of in connection with the brickkiln were employed in the preparation of the clay; and if this view be correct, the passage is interesting as evidence of the use of machinery in making bricks at a very early period of history. III. The Romans used bricks, both burnt and unburnt, in great profusion; all the great existing ruins at Rome being of brick. At the decline of the Roman Empire, the art of brickmaking fell into disuse, but was revived in Italy after the lapse of a few centuries. The me¬ diaeval ecclesiastical and palatial architecture of Italy mental work in terracotta; cornices and other deco¬ rations of great beauty being executed in the latter I material. IV. In Holland and the Netherlands, the scarcity of stone led, at an early period, to the extensive use of brick, not only for domestic but for ecclesiastical buildings, and these countries abound in fine specimens of brickwork, often in two colours, combined with great j taste, and producing a very rich effect, as in the celebrated j examples at Leeuwarden in Friesland. It is worthy of ; remark, that in the fens of Lincolnshire and Norfolk, | where we should naturally have expected to have found | the same material made use of, the churches, many of which are exceedingly fine specimens of architecture, 4 INTRODUCTION. •are built of small stones, said to have been brought from a great distance on pack-horses. V. Brickmaking appears to have been introduced into England by the Romans, who used large thin bricks or wall tiles as bond to their rubble constructions; and such wall tiles continued to be used in England until rubble work was superseded by regular masonry, about the time of the Norman Conquest. Brick does not appear to have come into general use as a building material until long afterwards. In the reign of Henry VIII., however, the art of brickmaking had arrived at great perfection, and the remains of many buildings erected about this time exhibit some of the finest known specimens of orna¬ mental brickwork. The following is a list of some of the principal brick buildings erected at the period of which we speak:— NAME. Hurst Monceaux Castle, Sussex . Gate of the Ryehouse in Hertfordshire Lollards’ Tower, Lambeth Palace Old part of Hampton Court Tattershall Castle, Lincolnshire . Oxborough Hall, Norfolk . Hengrave Hall, Suffolk Gateway, Rectory, Hadleigh, Suffolk . Manor House, at East Barsham, Norfolk Thorpland Hall, Norfolk Parsonage House, Great Snoring, Norfolk WHEN BUILT. Early in the reign of Henry VI. Ditto. a.d. 1454. A.D. 1514. a.d. 1440. About a.d. 1482. Finished a.d. 1538. Close of 15th century. During the reign of Henry Vll. Ditto. During the reign of Henry VIII. Many of these buildings have been engraved in Pugin’s “ Examples of Gothic Architecture,” to which we would refer the reader. The decorative details of the Manor House at East Barsham and of the Parsonage House at Great Snoring are particularly worthy of notice; the panelled friezes, cornices, and other ornamental work INTRODUCTION. being constructed of terracotta moulded to the required form. The use of terracotta for decorative panels and bas-reliefs appears to have been common during the reign of Henry VIII. The gateway of York Place, Whitehall, designed by Holbein, was decorated with four circular panels, which are still preserved at Hatfield Peveril, Hants. The gateway of the Rectory in Hadleigh churchyard is very similar in character to that at Oxborough Hall, engraved in Pugin’s work, above referred to. It has been lately restored very carefully, the terracotta work for the purpose being made at the Layham Kilns, near ITadleigh, in moulds of somewhat complicated con¬ struction. In the time of Queen Elizabeth, brick seems only to have been used in large mansions. For common buildings, timber framework, filled in with lath and plaster, was generally used, and this construction was much employed, even when brickwork was in common use, the brickwork, up to a late period, being merely introduced in panels between the wooden framing. VI. On the rebuilding of London after the great fire of 1666, brick was the material universally adopted for the new erections, and the 19th Car. II. c. 11, regulated the number of bricks in the thickness of the walls of the several rates of dwelling-houses. One of the resolutions of the corporation of the city of London, passed about this time, is interesting; it is as follows;—“And that they (the surveyors) do encourage and give directions to all builders, for ornament sake, that the ornaments and projections of the front buildings be of rubbed bricks; and that all the naked parts of the walls may be done of rough bricks, neatly wrought, or all rubbed, 6 INTKODTJCTION. at the direction of the builder, or that the builders may otherwise enrich their fronts as they please.” Much of the old brickwork still remaining in London, in buildings erected at the end of the 17th and be¬ ginning of the 18th century, is very admirably executed. The most remarkable feature of the brickwork of this period is the introduction of ornaments carved with the chisel. A fine example of this kind of work is shown in the Frontispiece*', which is a sketch of No. 43, St. Martin s Lane, one of a block of houses built by a person of the name of May, who about the same time erected May’s Buildings, to which the date of 1739 is affixed. The house in question is said to have been intended by Mr. May for his own residence. Its deco¬ rations consist of two fluted Doric pilasters, supporting an entablature, the whole executed in fine red brickwork; the mouldings, flutings, and ornaments of the metopes having been carved with the chisel after the erection of the wallsf. VII. It was not till the close of the last century that bricks were subjected to taxation. The 24 Geo. III. c. 24, imposed a duty of 2s. 6d. per thousand on bricks of all kinds. By the 34 Geo. III. c. 15, the duty was raised to As. per thousand. By the 43 Geo. III. c. 69, bricks were divided into common and dressed bricks, The author is indebted to the kindness of Mr. Edis for this sketch of one of the most interesting specimens of ornamental brickwork in the me¬ tropolis. t The author is indebted for this information to Mr. Cannon, Foreign Bookseller, of No. 11, May’s Buildings. This gentleman, who has paid much attention to architecture, took advantage of the opportunities afforded by the erection of scaffolding, at a time when the house was undergoing repair, to make a minute examination of these decorations. INTRODUCTION. 7 and separate rates of duty were imposed on each kind. These duties and those on tiles were as follows:— SCHEDULE (A)—DUTIES. BRICKS AND TILES. £ s. d. For every thousand bricks which shall be made in Great Bii- tain, not exceeding any of the following dimensions, that is to say, ten inches long, three inches thick and five inches wide ....•••••• For every thousand of bricks which shall be made in Great Britain exceeding any of the foregoing dimensions . For every thousand of bricks which shall be made in Great Britain, and which shall be smoothed or polished on one or more side or sides, the same not exceeding the superficial dimensions of ten inches long by five inches wide For every hundred of such last-mentioned bricks, exceeding j The duties or the aforesaid superficial dimensions . . , . J P avm S- tlles - For every thousand of plain tiles which shall be made in Great Britain ....•••••• For every thousand of pan or ridge tiles which shall be made in Great Britain . .. For every hundred of paving tiles which shall be made in Great Britain not exceeding ten inches square . For every hundred of paving tiles which shall be made in Great Britain exceeding ten inches square. For every thousand tiles which shall be made in Great Britain, other than such as are hereinbefore enumerated or described, by whatever name or names such tiles are or may be called or known, .. N.B.—The said duties on bricks and tiles to be paid by the maker or makers thereof respectively. By the 3 William IV. c. 11. (1833), the duties on tiles # were wholly repealed, and two years afterwards the duty 0 5 0 0 10 0 0 12 0 0 4 10 0 12 10 0 2 0 4 10 0 4 10 * By a curious oversight, this Act, which was intended to put roofing tiles on the same footing as slates, also repealed the duties on paving tiles, whilst bricks used for paving remained subject to duty as before. Thus a lump of clay put into a mould 10 in. x5in. x3 pays duty, but the same quantity of clay put into a mould 10 in. square is duty free, because it comes under the denomination of a tile. The manufacturer and not the public reap the advantage thus given. 8 INTRODUCTION. on bricks was again raised, making the duty on common bricks 5s. 1(M per thousand. The brick duties formed the subject of the 18th Report of the Commissioners of Excise Enquiry, 1836; and m 1839, these duties were repealed by the 2 and 3 Viet. c. 24, and a uniform duty of 5s. 10 d. pei thousand imposed on all bricks of which the cubic content does not exceed 150 cubic inches, without any dis¬ tinction as to shape or quality. See Appendix, A and B. VIII. The new Act is a great boon to the public as well as to the tiade, as, in consequence of the removal of the restrictions on shape, bricks may be made to any lequiied pattern; and moulded bricks for cornices, plinths, string-courses, &c., can be manufactured at a moderate price. Under the old regulations, also, the brickmaker was precluded from correcting any defect which might arise from warping or twisting in the process of drying, without making himself liable to pay the higher rate of duty; this being no longer the case, a very supeiioi article can now be made at a price very little exceeding that of common bricks under the old regulations. IX. By the new Act*, bricks made and used solely foi the purpose of draining wet and marshy land are exempted from duty, provided they are legibly stamped, in making, with the word u Brain,” and a penalty of fifty pounds is imposed on every person who shall use such bricks “ for any other purpose than in draining wet and marshy lands and in constructing the necessary drains, gouts, culverts, arches and walls of the brick- woik piopei and necessarily required for effecting and maintaining the drainage of such lands.” * This exemption was originally granted by 7 Geo. IV. c. 49, s. 3. INTRODUCTION. 9 The meaning of this clause is not very clear, and it is a question whether the exemption cannot be claimed for all bricks used in the erection of bridges over drains, inasmuch as the drainage of the districts through which they pass could not be maintained without the erection of such bridges. The great number of archways and culverts required in the construction of a railway renders it most desirable that the limits of exemption should be clearly defined. Some information on the point will be found in the Appendix, C, D, and E. X. The number of bricks annually made in Great Britain is very great, the number annually brought to charge during the last few years being nearly 1,800,000,000, and the annual duty amounting to be¬ tween 500,000/. and 600,000/. Comparatively few bricks are made in Scotland, on account of the abundance of stone everywhere to be had in that country, the duty paid on bricks in Scotland being only about of the whole amount above named. It is impossible to ascertain the number of bricks annually made in Ireland, as no duties are paid on bricks manufactured in that country. Those who are not practically connected with en¬ gineering works may find some difficulty in forming a clear conception of the immense number of bricks annually made for railway purposes; and which may be roughly estimated at from 600 to 800 millions annually. In 1821, before the introduction of the railway system, the number of bricks charged with duty in England and Scotland amounted to 913,231,000. In 1831 the number was 1,153,048,581. In 1840 the number rose to 1,725,628,333. A common turnpike road bridge over a railway requires for its construction, in round numbers, 300,000 b 3 10 INTRODUCTION. bricks; and the lining of a railway tunnel of ordinary dimensions consumes about 8000 for every yard in length, or in round numbers about 14,000,000 per mile. XI. The processes employed in the manufacture of bricks differ very greatly in various parts of the country. In some districts the clay is ground between rollers, and the pugmill is never used. In others, both rollers and pugmills are employed. In the neighbourhood of London rollers are unknown, and the clay is passed through a wash mill. Equal differences exist in the processes of moulding and drying. Lastly, the form of the kiln varies greatly. In many places the common Dutch kiln is the one employed. In Essex and Suffolk the kilns have arched furnaces beneath their floors; in Staffordshire bricks are fired in circular domed ovens called cupolas; whilst near London kilns are not used, and bricks are burnt in clamps, the fuel required for their vitrification being mixed up with the clay in the process of tempering. In the following pages we have described at con¬ siderable length the practice of brickinaking as carried on in Nottinghamshire, Staffordshire, Suffolk, and in the neighbourhood of London; and although.the practice of almost every county presents some local peculiarity, the reader who has carefully gone through these ac¬ counts will be enabled to understand the object of any processes not here described, and to form a tolerably correct judgment as to whether the process of manufac¬ ture in any district is conducted in a judicious manner; or whether the brickmaker has merely followed the practices handed down by his predecessors without any consideration as to the possibility of improving upon them. Before, however, entering upon the practical de- ART OF MAKING BRICKS AND TILES. 11 tails of the subject, it is necessary that the reader should have some knowledge of the general principles of brick¬ making, and of the nature of the processes employed; and these we shall proceed to consider in the following chapter. CHAPTER I. GENERAL PRINCIPLES OF THE MANUFACTURE OF BRICKS AND TILES. I. BRICKS. 1. The whole of the operations of the brickmaker may be classed under five heads, viz.: Preparation of brick earth. Tempering. Moulding. Drying. Burning. We propose in this chapter to describe these operations one by one, pointing out the object to be effected by each, and comparing at the same time the different processes employed in various parts of this country for the same end. PREPARATION OF BRICK EARTH. 2. The qualities to be aimed at in making bricks for building purposes may be thus enumerated:—Sound¬ ness, that is, freedom from cracks and flaws; hardness, to enable them to withstand pressure and cross strain; regularity of shape, that the mortar by which they are united may be of uniform thickness to insure uniformity 12 RUDIMENTS OF THE of settlement; uniformity of size, that all the bricks in a course may be of the same height; uniformity of colour, which is of importance only in ornamental work; facility of cutting, to enable the bricklayer to cut them to any given shape, as required in executing all kinds of gauged work; lastly, for furnace-work and all situations exposed to intense heat, infusibility. 3. Success in attaining the desired end depends almost entirely on a proper selection of brick earths and their judicious preparation before commencing the actual process of brickmaking; the subsequent opera¬ tions being matters of mechanical routine. Brick¬ making, therefore, may be viewed in two lights—as a science, and as an art; the former having been little studied and being very imperfectly understood, whilst the latter has been brought to great perfection. 4. The argillaceous earths suitable for brickmaking may be divided into three principal classes, viz.:— Pure clays, composed chiefly of one-third alumina with two-thirds of silica, but generally containing a small pro¬ portion of other substances, as iron, lime, salt, mag¬ nesia, &c. Marls, which may be described as earths containing a considerable proportion of lime. Loams, which may be described as light, sandy clays. It very seldom happens that earths are found which are suited for the purpose of brickmaking without some admixture. The pure clays require the addition of sand, loam, or some milder earth; whilst the loams are often so loose that they could not be made into bricks without the addition of lime to flux and bind the earth. Even when the clay requires no mixture, the difference in the working of two adjacent strata in the same field is often so great that it is advisable to mix two or three sorts ART OF MAKING BRICKS AND TILES. 13 together to produce uniformity in the size nnd coloui of the bricks. 5. Alumina may be considered as the principal in¬ gredient in all brick earth, and it is this which gives to clay its plastic quality. Alumina alone, or the pure clays containing but little sand, when beaten up with water into a stiff paste, may be moulded with great ease into any shape; but will shrink and crack in diying, however carefully and slowly the operation be con¬ ducted ; and will not stand firing, as a red heat causes the mass to rend and warp, although it becomes very hard by the action of the fire. The addition of any substance which will neither combine with water nor is subject to contraction gieatly remedies these defects, whilst the plastic quality of the clay is not materially affected. For this reason the strong clays are mixed with milder earth or with sand. The loams and marls used for brickmaking in the neighbourhood of London are mixed with lime and sifted breeze for the same purpose, and also to effect the fluxing of the earth, as will be presently described. 6. Silica being infusible either alone or combined with alumina in any proportion whatever, those clays which contain sufficient sand to enable them to stand filing, and are at the same time free from lime or other fluxes, are, from their refractory nature, very valuable for making fire bricks, fire lumps, and similar ai tides, for lining furnaces as well as for making crucibles, glass¬ house pots, and other articles exposed to intense heat. But, although silica and alumina alone form an infusible compound, a comparatively small quantity of oxide of iron renders the clay fusible at furnace heat, if the silica and alumina are nearly in equal proportions; and in 14 RUDIMENTS OP THE using fire clays containing oxide of iron, which are subject to considerable contraction through excess of alumina, care must be taken in correcting this defect not to add too much siliceous sand, or a fusible com¬ pound might be pioduced. fio avoid this it is common, in making fire bricks, to substitute for the sand used in the ordinary processes of brickmaking, broken crucibles, old file biicks, and glass-house pots, ground to powder. Fire clay being an expensive article, it is usual when making fire bricks at a distance from the mines to mix with it burnt clay, for the sake both of economising the material and diminishing its contraction. Mr. Pellatt states, that Stourbridge clay, when carefully picked, ground, and sifted, will bear for brickmaking two pro¬ portions (by weight) of burnt clay to one of native clay. The best fire clays are natural compounds of silica and alumina, free from lime, magnesia, and metallic oxides. 7. The table in the opposite page shows the consti¬ tuents of several infusible earths. 8. Fire clay is found throughout the coal measures, but that of Stourbridge is considered to be the best, as it will bear the most intense heat that can be produced without becoming fused. Next in esteem to those of Stourbridge are the Welsh fire bricks, but they will not bear such intense heat. Excellent fire bricks are made at Newcastle and Glasgow. Fire bricks are made near Windsor, at the village of FXedgerly, from a sandy loam known by the name of Windsor loam, and much used in London for fire-work, and also by chemists for luting their furnaces and for similar purposes. The relative merits of Windsor, Welsh, and Stour- bridge fire bricks are best shown by their commercial value. ART OF MAKING BRICKS AND TILES, s a S'-g • ►,■2.8 rt o w o o co 009 CM O *0 ^ O # c3 0) O S) T3 o ® . 2 * ho a5 g*8 o 01 X p ^ rt « a . 'SuiqSiaM. ipsa ua'aMisq sinoq ui iBAiajui •saourto ui ;qSi 3 M jo ssot; HCO _|rf - CO CM O N Oi O ‘O ‘O *0 £ & l> H CO I> < —< CO CO £ £ £ Tf< £ - - - to - 3 < O T 3 \3 O cj 3 ® O r3 32 *53 3 ^ ^ rC ... V. bO be .5 0) 3 bo £ ’5 ’G H .a o ART OF MAKING BRICKS AND TILES. 101 The total loss of weight in drying and burning is as follows:— 196 ounces, the weight of a brick wet from the mould. lost by drying, or 23£ per cent. dry ready for the kiln, lost in burning, or 14 per cent. of an ordinary blue brick. 13. Burning .—The oven is of a circular form, with a spherical top, and will contain 8000 bricks, which are so placed as to allow a space between the sides of each for the action of heat, and an equal diffusion thereof. When the oven is full, the clammins or doorway is made up, and the fires kindled and kept burning 36 hours for red, and 38 hours for blue bricks, consuming 3^- tons of coals for the former, and 4 tons for the latter. The expense of setting, firing, and drawing an oven of 8000 bricks is as follows: labour 12 shillings, and coals 11. 135. 4d. 14. Cost of Manufacture .—The details of the cost of manufacture are as follows : — £ s. d. Clay getting.per 1000 0 1 6 Tempering and moulding ... „ 049 Setting oven, firing and drawing . . „ 0 16 Coals, 4 tons at 8s. 4 d., divided amongst 8000 „ 0 4 2 Duty, 5s. 10c?., with 5 per cent, added . „ 0 6 1£ Rent, machinery, clay, contingencies, and profit „ 0 9 11^ Present selling price for ordinary blue bricks „ 18 0 15. Rental. —Brick-yards with mines of marls are set with the following appendages, viz.: 1 oven, moulding or drying-house, and pug-mill, with a breadth of brick floor and marl bank sufficient to work one oven for 30 1. per annum ; if two ovens are worked in one take, thev are set at 2 51. each. 46 150 21 129 Fiy- 1. Fig. 2. Fig. 3. ART OF MAKING BRICKS AND TILES, 103 17, Fig. 4. Isometrical, View of a Moulding Table. a. Sand basket. B. Detached water-box. c. Moulding board. D. Water-box. E. Clay knife. In the process of moulding the moulder takes in his hand, from the basket, a portion of sand, and dusts upon that part of the table where he rolls the clay into the form necessary to mould; also upon the moulding board. The water-box or trough, b, is used by the boy to wash the mould in, and is lower than the table, so as to be convenient for that purpose. The water-box, d, is level with the table, and is used to throw the strike in after each time of using. 18. Fig. 5. Isometrical View of a Brick Mould. N.B. The mould is made of oak, the edges plated with iron. ART OF MAKING ERICKS AND TILES. 105 Fig. 8. Elevation. Fig. 9. Section, on line c D, Fig. 6. SECOND EXAMPLE.-TILE-MAKING. 20. At Basford there is an extensive hill of good marls, from which 8 brick-yards are supplied (working 14 ovens), some of which have been in work for 40 years. The makers are subject to the rental stated in art. 15. The leading article made at these yards is roofing tiles; f 3 106 EUDIMENTS OF THE besides which are also made some quarries, dust-bricks, drain-tiles, and just so many common bricks as are necessary for the manufacture of tiles, it being necessary in order to set the oven properly to burn 2000 bricks with every oven of roof tiles, as will be hereafter explained. The process of tile making here is as follows :-r- 21. Weathering and Tempering .—The marl is dug and spread upon slopes of this hill (which has a south¬ east aspect) to weather; the length of time depends j upon the quality of the air: a hot dry summer’s day will do good service, and three or four such days would enable the makers to collect a thin surface in a work¬ able condition. Frosty weather, provided it be dry, is preferred; wet, and alternations of wet and dry, retard the process of what is termed weathering. During a hot dry season marl can be dug, weathered, and made in one month, and this is frequently done. At the yards here referred to, the workers collect their marls, so wea¬ thered, at the foot of these slopes, and mix them with a quantity of water. That to be used for tiles is placed in the pug-mill, and about 1 cube yard per hour is ground by one horse; and that used for common bricks is not ground, but simply mixed and tempered. The pug-mill consists of a wooden tub slightly ta¬ pered, the largest end being uppermost; it is circular and about 6 ft. high and 3 ft. diameter at the top or largest end, in which a cast-iron spindle revolves, j carrying a series of flat steel arms, arranged so as to | form by rotation a spiral or worm-like motion upon the clay, which is thereby pressed from a larger to a less diameter of the tub in which the clay is confined, and ultimately comes oozing out of an aperture at the bottom : this operation kneads the clay, and more com¬ pletely mixes it, giving it great cohesive power. This ART OF MAKING BRICKS AND TILES. 107 clay or prepared marl is now ready to make roof tiles, dust bricks, quarries, &c., and is wheeled away to the stock kept under cover for that purpose. The tiles, and all articles in the making- of which coal dust is used, are made in a building called by brickmakers the hovel ! or drying house; but they prefer placing their tiles when first moulded in the open air, weather permitting. The moulding of roofing tiles varies from that of bricks before described, principally in the clay being stiffer, and coal dust being thrown in the mould each time it is filled. 22. Moulding .—The mould is 12 in. by 7f in. and in. thick, made of oak plated with iron. The moulder at his bench takes up a lump of clay, and works it by hand into an oblong square, somewhat less than the mould, say 11 in. by 7 in. or thereabout; the mould is placed upon the bench, and fine coal dust thrown into it; the man then takes up the lump of clay in the right po¬ sition for the mould, and throws it into it with con¬ siderable force; then with a brass wire strained upon a ! wooden bow cuts off the surplus clay level with the mould, ' removes the lump, and finishes moulding the clay left ’ in the mould by adding a little clay if it be wanted, and j smooths it over with a wooden tool. By his side upon the bench he has two thin boards about the size of the moulded tile, their surfaces are dusted over with coal dust, upon one of these he places the moulded tile, without the mould, the half circular projections ex¬ tending beyond the board, and so he repeats the process of moulding at the rate of from 1300 to 1500 per day, adding more clay to his lump about every six tiles moulded, and in quantity about as much as the six tiles moulded. 23. Drying .—The attendant boy carries away two 108 RUDIMENTS OF THE tiles at each time to the floor; he takes up one on the board, and by the thick part of the hand presses up the two projections at right angles with the face of the tile, and then places board and tile on his head, and takes up a second and operates upon this in like manner, as he walks to the floor, where he lays the two tiles, carrying the boards back to the moulding bench, and so he repeats his operations. The tiles remain on this floor, out of doors in fine weather, about four hours; they are then collected and placed close together, the nib end changed alternately to allow of their resting close and square; in this state they are walled up in a dry but not hot situation, and so remain for a day or two: this is said to toughen them. 24. The Set .—The next process is to give them a curved form, sometimes termed the set, which is done on a three-legged stool, called a horse, the top of which is a little larger than the tile, and is curved one way to about a ten feet radius. With the horse is used a wooden block, curved to correspond with the surface of the horse. These implements are used as follows: six tiles are taken as last placed and put on this horse; the man lifts up the wooden block and gives them three sharp blows with it; they are then carried away and placed in an ingeniously built wall to complete the drying process (the wall built with the tiles to be dried), after which they are carried to the oven, twelve at each time, in a peculiar manner, with the edge of the tiles against the breast of the carrier. 25. Quarries and dust bricks are moulded in like manner from stiff clay, coal dust being used to facilitate the articles leaving the mould. 26. Drain Tiles .—Pipe drain tiles are made as ART OF MAKING BRICKS AND TILES. 109 follows: the clay is first moulded to the length, width, and thickness required, and then wrapped round a drum, the edges closed together by hand, the drum or mandril turned round, and the pipe tile shaped by the operator’s hand, assisted in some cases by a wooden tool: this is the mode of making pipe tiles from 3 in. to 16 in. in diameter, whether cylindrical, tapered, or egg-shaped. The usual length is 18 in., and the diameter from 3 in. to 9 in. They are sold at 1 d. per in. bore, that is, a pipe 3 in. in diameter and 18 in. long, would cost at the yard 3d.; and a pipe 9 in. in diameter and 18 in. long, 9 d. This price applies to cylindrical pipes without sockets. 27. Tile Machines .—One of Ainslie’s machines has lately been introduced into this neighbourhood, upon the estate of the Duke of Sutherland, for makino- small tubular drain tiles, which makes two pipes 1|- in. in diameter at the same time. The prepared clay is forced through two dods to form the tubes, which are cut into lengths by wires affixed to the machine, and when partially dry are rolled straight by hand upon a flat surface, and then set up in racks to finish the drvin°- process. 28. Firing .—Firing the articles enumerated in the previous description, requires much more care than firing bricks, and as roof tiles are the thinnest and require most care, the largest sized pipe tiles excepted, we shall describe firing an oven of such tiles. On the bottom of the oven are first placed 2000 bricks, as shown in fig. 13, and upon these are placed 7000 tiles, forming a square, the spaces between the tiles and the curved side of the oven being filled up with bricks, as shown in fig. 14. The tiles are placed 110 rudiments of the edge-wise, in parcels of twelve, changing their direction each parcel of twelve. The nibs on the tiles space them off from each other, and support them in the vertical position; from this description, and a reference to the illustrations, it will appear, that the goods placed in the oven are in each case so placed as to allow the diffusion of heat between them; and as the uniformity of heat is the desideratum in firing blue bricks and tiles, the circular oven is found to answer better than any other at present in use. It is necessary to have a wall round the outside of the oven, about 6 ft high, and at a distance therefrom to allow the fireman space to attend his fires conve¬ niently ; this wall is dry built generally with imperfect bricks, and its use is to avoid one fire being urged more than another by the set of the wind, which duty it performs tolerably well. The oven being set, the clammins (doorway) is made up with bricks daubed over with street sweepings as a loam; then the fires are kindled, and are kept slowly burning for the first 5 hours, after which they are pro¬ gressively increased for the next 33, making 38 hours for hard fired blue tiles or bricks; four tons of coal being consumed in the firing. The heat is determined by the sight of the fireman directed to the mouths and top outlet of the oven. When the heat is obtained, and before the fires burn hollow, the mouths are stopped up with ashes to prevent the currents of cold air passing through the oven, which is then suffered to cool gradu¬ ally. An oven is usually fired once a week, but may be fired three times in a fortnight. After firing, twenty- four hours should be allowed for cooling before an oven is opened to take out the tiles. 29. The following table shows the selling price per : ART OF MAKING BRICKS AND TILES. Ill 1000, and cost per superficial yard, of quarries, dust bricks, and roof tiles :— Size. Price per 1000. Superficial mea¬ surement per 1000. Price per superficial yard in pence. Thickness. Description. 6 in. sq. 35s. 27‘89 yards. 15-00 \ 7 „ 46s. 3780 „ 14-59 r1 inch Quarries. 9 9 ) 80s. 62-50 „ 15-36 H » 99 9x4i 40s. 31-25 „ 14-33 2 „ Dust bricks. 10-8x7 „ 25s. 58-33 „ 514 1 2 99 Roof tiles. DESCRIPTION OF ILLUSTRATIONS. 30. Fig. 10. Isometrical View of a Bench for moulding Tiles. a. Coal dust box, 14 inches by 8 inches. B. Moulding board, 14 inches by 10 inches, c. The bow. 31. Fig. 11. Elevation, showing the Manner in which the Tiles are placed during the last Drying. 112 RUDIMENTS OP THE 32. Fig. 12. Tile Block and Horse. 33. Fig. 13. Plan of Oven , as seen when eight courses of Bricks are placed edgewise. The eight rows of twelve bricks in each, as seen in plan, cover a space left in continuation of flues from the eight fire-holes. The bricks in the first seven courses are so placed as to leave a flue of an average width of four inches. The dotted lines show the position of the fire-holes. ART OF MAKING BRICKS AND TILES. 113 34. Fig. 14. Plan of Oven, as seen when the first course of Tiles are 'placed, upon the Bricks , as seen in Fig. 13. The tiles are placed in bungs of twelve, and laid alternately cross and lengthwise, the nib spaces them off, and supports them in a vertical position. Each side of the square is made up with bricks, as shown on the plan. 35. The manufacture of bricks, &c., for building and paving purposes, in a systematic manner, in suitable premises with improved conveniences, so that the opera¬ tives may be employed the whole of the year instead of a portion of it as now, is a subject deserving the attention of the capitalist and inventor. Improvements in the quality and conveniences of this manufacture are inti¬ mately connected with the moral, intellectual, and physical condition of society, as may be seen by a visit to any otdinary brickyard, and a reference to the evidence before the Sanitary Commission. Where ex¬ tensive supplies of marls or clay are found, suitable works might be erected for such manufacture, could a 114 RUDIMENTS OF THE cheap and ready mode of transportation be commanded, so as to carry bricks, &c. a distance of 60 to 100 miles without materially increasing their price. 36. Assuming the weight of bricks to be 3|- tons per thousand, the present railway charges for the carriage of bricks, viz. 2d. per ton per mile, if under 40 miles, and If d. per mile if more than 40 miles, would add to their cost as follows:— If carried under 40 miles. 0 0 7 per 1000 per mile. Or for a distance of 39 miles . 1 2 9 And if carried above 40 miles. 0 0 6 per 1000 per mile. Or for a distance of 60 miles. 1 10 7 Therefore a carriage of 60 miles at the lowest railway rate more than doubles the value of a common brick compared with the price at the yard. The high rate of charge for carriage, and the duty, which amounts to nearly 22 per cent, of the selling price at the yard, con¬ stitute obstacles to the improvement of the brick manu¬ facture, and the bettering of the condition of the opera¬ tives employed therein. The recent improvements in connection with domestic comfort and health, and the encouragement offered to architectural improvements, in the houses for artizans, may probably awaken an interest in this department of industry, and place even brickmaking in the position its importance deserves, if not demands. ART OP MAKING BRICKS AND TILES, 115 O fa fa m fa < fa O fa o MJ fa m fa fa fa fa « a Is nd fa 3 •£ 10 o m fa s „ * CD C5 o'° ^ fa O •jpuq -ai]} Br-gnq }q3t[ suinq ‘preui joSSes 00 CO ^ .00 . tH . co io ; go ; ^ : cb • 6o ; cb • io cm : : : ce CN 99-73 *anjq uinq }ou him. pui? *pai suinq ‘I’uaix-uodn -a^o^S uio.ij &q\o t> Cl CO -ct< . O CD CM —' -CO 6 fa os : fa CO C l Trace. 1-40 3-89 100-31 •arqq pooS suinq ‘p pne *£ ‘S ‘I ‘son ‘stop jo ain-jxijv CO 59-44 2593 1074 Trace. 311 99-22 •s;pui }l i reaq aqa pu«;s }ori HiM.qxeui pa.i ua^on *c 42-84 17-61 6-97 15-36 11-61 2-20 3-94 100-53 •qsippai anjq suinq ‘jieui pajSuiH t> XO . 05. —1 Cd : CM c cb cb : rH t> r-H CO 00 101-98 •anjq qstppai suinq ‘Iibui MOjiaA dox CD 65-78 15-16 8-49 1 -67 CD fa 96-47 •aniq poof suinq f [ii3ui pannopa unQ Cl 64-32 20-33 10-86 Trace. o CO cb 102-11 •anjq suinq qaiqAV ‘[ii?in pan - 69-87 16-79 8-88 Trace. CO d fa 08-66 Number of analysis. Silicic acid. Alumina. Peroxide of iron, with a little protoxide. Protoxide of iron, with a little peroxide. Lime ... nprhnnir*. arid ... Oxide of manganese . Knda and a littlp nntash .. Water.,.... TABLE 2.—The Clays in Table 1 arranged in the order of infusibility, beginning with the most easily fusible clay, and calling that No. 1, 116 RUDIMENTS OF THE CO 70-17 4 6987 1 o 3 .2° CO 10-74 23.65 (0) > to o § 5 CD a co o CO os w K) 4-. oo O G «+- o CO 05 cfl CO o 3 c Cl) o o o cb ** ■o *© o 5" Ui l> 35-18 P- r —-t CO © © © © «0 © © © 1—i (M rl © r-H r-» f-H r-H r—4 © © »o i—I ih CM © CM © © r-H CM © # © © CM © i-H r—i r-, © © © ’ ‘ o o © © 94 APPENDIX. (I.) Brickmaking in Suffolk. Two kinds of bricks are made in Suffolk, viz., reds and whites. The latter are much esteemed for their shape and colour, and large quantities are annually sent to London, for facing build¬ ings of a superior class. Clay .—The supplies of brick-earth are chiefly derived from the plastic clays lying above the chalk, although the blue clay is occasionally used. The clays in most parts are too strong to be used as they rise, and have consequently to be mixed with a white loam or a milder earth. Tempering .—The clay is turned over in February and March, and in some parts of Suffolk it is passed through the ■wash-mill, but this is not generally the case. Tempering is generally performed by spade labour, but the pug-mill is sometimes used, although not commonly, for white bricks; it is, however, used for all other white ware. Moulding.—-The brick mould is of wood, shod with iron; the dimensions vary slightly’- according to the nature of the clay, but are usually as follows: 9|ths long by 4}|ths wide and 3^ deep. There is no hollow formed in the bottom of the brick for the mortar joint. Brass moulds are unknown. Sea sand is used in the process of moulding, for sand¬ ing the mould and the table. 1 he strike is used for taking off" the superfluous clay from the mould. The use of the plane is not known. I Drying .—The bricks are not dried on flats as in the Midland Counties, but are taken directly from the moulding stool ! to the hacks. Sheds are used in some yards, and drying houses with flued floors are used in winter for pan-tiles I and kiln-tiles, but not for bricks. The length of a hack is about 70 yards, and each I moulder will keep four hacks going. lhe time required for drying in the hacks of course varies according to the weather, but may be stated on an i aveiage at about lb days for red bricks. White bricks 1 dry somewhat quicker. APPENDIX. 95 The contraction of the clay in drying amounts to about | in. in the length of a brick, and, if properly burnt, the shrinkage in the kiln is imperceptible. The weight of a brick when first moulded, is about 8 lbs.; when dried, about 7lbs.; and when burnt, about 6 lbs.; but much depends upon the nature of the earth. Burning.—The construction of the kiln is quite different from that of the kilns used in other parts of England, having two arched furnaces running its whole length underneath the floor, which is formed of a kind of lattice work, through the openings of which the heat ascends from the furnaces below. The cost of erecting a kiln to burn 50,000 whites is about £145. A kiln to burn 85,000 reds costs about £ 100 . The bricks are commonly set in the kiln in bolts two bricks long by ten on; but some brickmakers prefer to cross them in the alternate courses, in order to admit the heat more freely. The fuel used is coal, and the quantity consumed is about half a ton per thousand for white, and 7 cwt. per thousand for red, bricks. The time of burning is about 60 hours for white, and 40 hours for red, bricks ; white bricks requiring a greater heat than the red ones to bring them to their proper colour. The coal costs from 15s. to 16s. per ton. COST OF MANUFACTURE. The selling pi'ices vary from 80s. to £2 per thousand for reds, and from 42s. to £3 per thousand for whites. Of red bricks two qualities only are distinguished, viz., outside and inside; of white, four qualities are distin¬ guished, viz., best, 2nd, 3rd, and murrays. The price of the ordinary red brick is about 30s. per thou¬ sand, and the cost may be thus divided:—■ 96 APPENDIX. £ s. d. Clay digging, per thousand. 0 2 6 Tempering, ditto. 0 1 0 Moulding, ditto. 0 5 0 Drying, ditto. 0 0 6 Barrowing from hacks and setting kiln, ditto...010 Burning, ditto. 0 ]. 3 Drawing kiln, ditto. 0 0 8 Stacking, ditto . 0 0 3 Cost of labour per thousand TO 12 2 Coals, about... o 6 0 Duty. 0 6 H Rent, tools, contingencies, and profit . 0 5 8i Selling price at the yard, about £110 0 White bricks are made in many parts of England, but the Suffolk whites have the pre-eminence over all others. The white bricks made near Lincoln are remarkable for swelling when laid in work, which causes them to throw off the mortar joints, and renders it impossible to make use of them in good work. The clay from which these bricks are made extends from the Witliam northwards as far as the Humber, and, so far as we are aware, possesses the same property throughout this dis¬ tance, the bricks made from it at various points between the Witham and the Humber having the common defect of swell- ing after burning. A curious specimen of this may be seen in a large chimney at Saxilby, which has a complete twist, from the irregular swelling of the brickwork. The peculiar property of swelling after burning is not con¬ fined to the Lincolnshire white clay. The author was in¬ formed some years ago, by Mr. Vignoles, C.E., that some of the bricks made on the Midland Counties Line of Railway, between Rugby and Derby, had the same defect. For the above particulars respecting the Lincolnshire white bricks, we are indebted to Mr. William Kirk, of Sleaford. (K.) On the Making and Burning of Drain-Tiles. Extracts from a communication by Mr. Law Hodges, pub¬ lished in the Journal of the Royal Agricultural Society of Eng¬ land, Vol. Y. Part II,— J ° : APPENDIX. 97 “ Reflecting on these obstacles to universal drainage, where required, I conferred with Mr. John Hatcher (brick and tile maker, and potter, Benenden, Kent), on the possibility of erecting a kiln of common clay that would be effectual for burning these tiles, and of cheap construction—and the re¬ sult was the building one in my brick yard in July last, and the constant use of it until the wet weather at the commence¬ ment of this winter compelled its discontinuance, but not until it had burnt nearly 80,000 excellent tiles; and in the ensu¬ ing spring it will he again in regular use. “ I shall now proceed to take in order the six points enume¬ rated under the 9th head of the Prize Essays for 1845, as printed in the last volume of the Royal Agricultural Society’s Journal, viz.: — “ 1st. Mode of working clay according to its quality. “ 2nd. Machine for making tiles. “ 3rd. Sheds for drying tiles. “ 4th. Construction of kilns. “ 5th. Cost of forming the establishment. “ 6th. Cost of tiles when ready for sale. “1st Point. Working the clay. “ All clay intended for working next season must be dug in the winter, and the earlier the better, so as to expose it as much as possible to frost and snow. Care must be taken, if there are small stones in it, to dig it in small pits, and cast out the stones as much as possible, and also to well mix the top and bottom of the bed of clay together. It is almost im¬ possible to give minute directions as to mixing clay with loam, or with marl when necessary, for the better working it after- wards, as the difference of the clays in purity and tenacity is such as to require distinct management in this respect in va¬ rious localities; hut all the clay dug for tile-making will re¬ quire to be wheeled to the place where the pug-mill is to work it; it must be there well turned and mixed in the spring, and pro¬ perly wetted, and finally spatted down and smoothed by the spade, and the whole heap well covered with litter to keep it moist and fit for use through the ensuing season of tile-making. “ 2nd Point. Machine for making tiles. “ For the reasons already alluded to, I prefer Hatcher’s machine. Its simplicity of construction, and the small amount of hand labour required to work it, would alone recommend it; PART II. F 98 APPENDIX. for one man and three boys will turn out nearly 11,000 pipe tiles of one-inch bore in a day of ten hours, and so in propor¬ tion for pipes of a larger diameter; but it has the great ad¬ vantage of being movable, and those who work it draw it it along the shed in which the tiles are deposited for drying, previously to their being burnt: thus each tile is handled only once, for it is taken off the machine by the little boys who stand on each side, and at once placed in the rows on either side of the drying shed, thus rendering the use of shelves in the sheds wholly unnecessary, for the tiles soon acquire a soli¬ dity to bear row upon row of tiles, till they reach the roof of the sheds on either side; and they dry without warping or losing their shape in any way. “ The price of this machine is £25, and it may be proper to add, that the machine makes the very best roofing-tiles that can be made, and at less than half the price of those made by hand, as well as being much lighter, and closer, and straighter, in consequence of the pressure through the die. “ It is necessary, in order to ensure the due mixing of the clay, as well as to form it into the exact shape to fill the cylinders of the machine, to have a pug-mill. Messrs. Cottam and Hallen make these also, and charge £10 for them. This mill must be worked by a horse ; in general one day’s work at the mill will furnish rather more prepared clay than the machine will turn into tiles in two days. “ 3rd Point. Sheds for drying. “ The sheds necessary for this system of tile-making will be of a temporary kind: strong hurdles pitched firmly in the ground in two parallel straight lines, 7 feet apart, will form the sides of the sheds, and the roof will be formed also of hurdles placed endways and tied together at the top, as well as to the upper slit of the hurdle, with strong tarred twine, forming the ridge of the roof exactly over the middle of the shed. They must then be lightly thatched with straw or heath, and the sharpness of this roof will effectually protect the tiles from rain. Two of these sheds, each 110 feet long, will keep one of the kilns hereafter described in full work. “ N.B.—These sheds should be so built as to have one end close to the pug-mill and the clay-heap, only leaving just room for the horse to work the mill, and the other end near the kiln. Attention to this matter saves future labour, an<3 therefore money. Fig. 1 . APPENDIX. 99 Plan of Kiln at A 13, fig. 3. Plan of Top of Kiln. TOO APPENDIX. Fig. 3. “ 4th Point. * Construction of kilns- “ The form of the clay-kiln is circular, 11 feet in diameter, and 7 feet high. It is wholly built of damp earth, rammed firmly together, and plastered inside and out with loam. The earth to form the w T alls is dug out round the base, leaving a circular trench about 4 feet wide and as many deep, into which the fire-holes of the kiln open. If wood be the fuel used, three fire-holes are sufficient; if coal, four will be needed. About 1200 common bricks are wanted to build these fire-holes and flues; if coal is used, rather fewer bricks will be wanted, but then some iron bars are necessary—six bars to each fire-hole. APPENDIX. 101 Fiy. 4 . “ The earthen walls are 4 feet thick at the floor of the kiln, are 7 feet high, and tapering to the thickness of 2 feet at the top; this will determine the slope of the exterior face of the kiln. The inside of the wall is carried up perpendicularly, and the loam plastering inside becomes, after the first burning, like a brick wall. The kiln may he safely erected in March, or whenever the danger of injury from frost is over. After the summer use of it, it must be protected by faggots or litter against the wet and the frost of winter. “ A kiln of these dimensions will contain— 102 APPENDIX. 47,000 1-inch bore pipe-tiles. 82,500 H 5 9 20,000 If 99 12,000 Si 99 and the last-mentioned size will hold the same number of the inch pipes inside of them, making therefore 24,800 of both sizes. In good weather this kiln can be filled, burnt, and discharged once every fortnight; and 15 kilns may be ob¬ tained in a good season, producing— 705,000 1-inch pipe-tiles. Or 487,500 l£ „ Or 300,000 If „ and so on in proportion for other sizes. “ N.B.—If a kiln of larger diameter be built, there must be more fire-holes, and additional shed room. “5th Point. Cost of forming the establishment. The price charged by Messrs. Cottam and Hallen for the machine, with its complement of dies is . . £25 Price of pug-mill ...... . 10 Cost of erecting kiln. 5 Cost of sheds, straw ..... . 10 50 (The latter item presumes that the farmer has hurdles of his own.) “ 6 th Point. Cost of tiles when ready for sale. “ As this must necessarily vary with the cost of the fuel, rate of wages, easy or difficult clay for working, or other local peculiarities, I can only give the cost of tiles as I have ascer¬ tained it here according to our charges for fuel, wages, &c., &c. Our clay is strong, and has a mixture of stones in it, but the machine is adapted for working any clay when properly pre¬ pared. “ It requires 2 tons 5 cwt. of good coals to burn the above kiln full of tiles. Coals are charged here at 28s. per ton, or 1000 brush faggots will effect the same purpose, and cost the same money; of course some clays require more burning than others; the stronger the clay the less fuel required. “ The cost of making, the sale prices, and number of APPENDIX. 103 each sort that a waggon follows:— 1-inch-pipe-tiles >> If 2i 99 2 | Elliptical Tiles Soles . . . with four horses will carry, are as Cost. Sale Price. Waggon s . d . s . holds 4 9 per 1000 12 . 8,000 6 0 „ 14 . . 7,000 8 0 „ 16 . . 5,000 10 0 „ 20 . . 3,500 12 0 „ 24 . . 3,000 . . . .241 . 2,000 “ All these tiles exceed a foot in length when burnt. “ The cost price alone of making draining-tiles will be the charge to every person making his own tiles for his own use. If he sell them, a higher price must, of course, be demanded to allow for some profit, for credit more or less long, for bad debts, goods unsold, &c., &c.; but he who makes his own saves all expense of carriage, and, as his outlay will not exceed £50, the interest on that sum is too trifling to be regarded, and he has no additional rent to pay; and after he has made as many tiles as he wanted, his machine and pug-mill will be as good as ever, with reasonable care, and will fetch their value.” ILLUSTRATIONS TO PART II. PAGE General Arrangement of a London Brickwork .... 6 Section and Plan of Chalk-mill ....... 8 Grinding-wheel, and mode of connecting its Axle-tree with the centre Shaft .......... 9 Plan and Elevation of Clay-washing Mill . . . .10,11,12 The Cutters, the Outlet to the Shoot, and the Strainer . . .13 Elevation of Pug-mill . , . . . • • .14 Section of ditto 15 Isometrical View of the Moulding stool . . . • .16 ■ -Brick Mould and Stock-board . . .17 The Hack Barrow, loaded . . . . . . . .19 ■ -unloaded . . ..... 20 The Clamp—Transverse Section . ..... 27 -- Longitudinal ditto . . . . . . . 28 Plan of the lower and of the upper Course of Scintles ... 29 Detail of the end of the Upright....... 31 Elevation of Pug-mill of the London Tileries . . . . 52 Detail of the Knives, and Cross Section of the Tub ... 53 Plan and Section of Tile Shed . . . . . . . 54 The Sling, the Block and Stock-board, the Pan-tile Mould, and the Roll ..55 The Pan-tile Table ......... 56 The Washing-off Table.57 The Washing-off Frame, the Splayer, the Thwacking Knife, and the Thwacker ......... 58 The Thw'acking Frame placed on the Thwacking Stool . . 59 The Thwacking Horse ........ 60 Plan of Tile Kiln, taken through the Body, and Plan of the Basement 61 Two Sections of Tile Kiln ...... 62, 63 Transverse Section of the Furnaces ...... 64 Longitudinal Section of ditto . . . . . . .65 Plans of Clay Kiln ..99 Section of ditto .... ..... 100 Elevation of ditto . . . . . . . . .101