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I'' A II M E R S ' R E G I IS T E R 



397 



ra! run ofbricks is eiiiht and a half inches lone, 

 and Iburlccn courst's wiih moriar to llie yard 

 perpendicular, liius conr^uniing more bricks and 

 nioriar than the En<iiisli gauge, lor ilie same 

 quantity of work. The youn^j engineer must, 

 therefore, not only attend to the qnaliiy, but to 

 the size of bricks, whenever he makes contracts 

 for tlieir purchase. 



Although clay has been named as the proper 

 material for making bricks, yet every clay will not 

 answer equally wed. Pure clay is quite white, 

 and in burning does not change its color, as may 

 be noticed in tobacco pipes, which are made from 

 if. The brown color ol" conmion clay is usually 

 derived from oxide of iron, and this causes the 

 brick to assume a red color when liurii! ; but as 

 red bricks are not approved or used lur outside 

 work in London, where more bricks are made and 

 consumed than in any other part of liie world, the 

 brickmakers have contrived means of changing 

 their color in burning to a pale bufi, very much 

 resembling the color of Bath-sione, and which 

 gives buildings a much handsomer appearance, 

 and closer resemblance to stone, than would be 

 expected. The mode of coloring is kept as secret 

 as possible, among the manufacturers; but il is 

 partly produced by mixing powdered chalk with 

 the clay, and is, probably, greatly dependent upon 

 the firing of the kiln and the fuel used, since many 

 bricks that exhibit a beautiliil and perfect bulf 

 hue on their ou'.sides, are red and dark within, if 

 broken. i 



A stiir, tenacious, plastic clay is unfit for making i 

 bricks, as they generally split and fall to pieces in 

 burning. Brickmakers call such clay stroiig earth, 

 and they prefer what they term a 7nild earth ; that 

 is, one of less lenacitj^, and having more the char- 

 acter of loam. When the loamy soil is not found 

 naturally, it is itnitated by adding sand in consi- 

 derable quantity to earth that is too strong. The 

 London brickmakers, in addition to sand, con- 

 stantly add a considerable quantity of breeze to 

 their clay, and they assert that it is this material 

 liiat gives the peculiar character of color, hard- 

 ness, and durability, to London bricks. This is 

 somewhat corroborated by the country bricks, 

 made without breeze, being red and of a very dif- 

 ferent character. 



To explain the term breeze, which seems to 

 perform so important a pan, it becomes necessary 

 to say that throughout the immense metropolis 

 London, no fuel is used in any of the houses but 

 bituminous or blazi/ig coal, very similar to that 

 known in this country as the coal li-om Richmond 

 in Virgima. Every house has what is called a 

 dust-hole, in some external part of the premises, 

 into which the ashes and refuse of these fires .uv 

 put, and the same place is also a depository Ibr 

 any other olTal of the house, which must not be 

 thrown into the streets. The parish authorities 

 contract with persons having horses and carts to 

 clear these dust-holes about once a week or ofien- 

 er, without any expense or trouble to the house- 

 keeper, and the stuff' collected is all carried to 

 certain fixed depositories on the outskirts of the 

 town. Here hundreds of men, women, and chil- 

 dren, are daily employed in assorting and looking 

 over the mountains" ol' discarded treasure thus 

 brought in, and now become the property of the 

 contractor; apparently worthless in the eyes of 

 the public, but iiol so in fact, for most of the men 



who have undertaken this business, in conjunction 

 with that of scavenger or strcel-cieaner, have, in 

 ahnost every instance, amassed immense Ibrtuiies. 

 Th(! heaps of soil are carefully raked over, and 

 everj' atom of them passed through several gra- 

 dations of sifting, with sieves of various fineness. 

 Rags, old iron, metal, bones, and such things as 

 are usually thrown avvay, mixed wiih the refuse 

 fuel, form the aggregate of the mass, and all these 

 things are separated and placed in separate heaps. 

 Here the papei'-mak-er gets supplied with much 

 common rag ibr packing-paper. The old iron is 

 returned to the forge to be n)annliictnred inio scrap 

 iron. The hartshorn and ivory-black manulitcturer 

 .gets supplied with bone; much new and uncon- 

 sumed coal and cinders are obtained, and thi.s 

 lurnishes the only fuel with which all the bricks 

 of London are burnt, while the small and almost 

 incombustible matter, consisting of very small 

 cinders, and new coal, fire dust, decayed animal 

 matter, and whatever else may be mixed in the 

 mass is breeze. This breeze is mixed with the 

 clay, is in a great measure combustible when ex- 

 posed to the high heat required to burn bricks, and 

 it is said to assist the brick in getting red hot 

 throughout its substance, and otherwise to improve 

 it very materially. 



A great deal of care and trouble is necessary in 

 preparing the earth lor making good bricks, in or- 

 der to reduce it to one unifiorm texture, and to de- 

 prive it as much as possible ol all stones that might 

 destroy the form of the brick, by breaking in ihe 

 fire, or becoming vitiified. The bricks of Phila- 

 delphia are in general so good, that we will de- 

 scribe the process used there for making them, and 

 point out where it ditlers from that pursued near 

 London. Tlie clay in both places is invariably 

 dug in the autumn, and during the winter before 

 frost sets in. The ground is divided out into 

 square allotments called spits, four feet wide and 

 sixteen feet long, which surface, when dug a foot 

 deep, furnishes the right quantity of earth for one 

 thousand bricks, and of course each foot in depth 

 is equivalent to the same quantity. This earth is 

 shifted by barrows to an adjoining piece of ground 

 previously levelled to receive it, and sunk a little 

 under the general surface to prevent water running 

 off. On this it is worked, if in a fit state to make 

 bricks, if not, sand is added in sufficient c|uantitj', 

 according to the judgment of the workman, to 

 make it sufficiently short or mild, and at this pe- 

 riod the London brickmaker adds his breeze, 

 which, answering the purpose of sand, it is added 

 in less quantity, ll is then cut, slashed, and worked 

 wiih the spade, adding waterto it to soften it; and 

 the quantity of two spits being added together in 

 one Iieap, sufficient earth to make two thousand 

 bricks is exposed to the frost in each heap, and the 

 more severe the frost is, the better incorporation 

 will take place. Nothing more can be done with 

 it until spring, when the warm weather thaws the 

 heaps, and if the frosting has been effectual no 

 lumps will remain, but the whole will be converted 

 into a iiniibrmly soil and yielding mass. If two 

 wet, the heaps are opened and spread to dry, or if 

 too dry, more water is added, before the last work- 

 ing with the tool, called tempering, in order to ren- 

 der the whole mass uniformly smooth ; it is then 

 pressed and jiatted down, and covered with boards, 

 cloths, or bushes, to prevent the injurious effects 

 of the sun and air, and is now ready for the moulder. 



