462 [Senate 



great number of kilns. Kilns are frequently burned in this way, con- 

 taining from five hundred thousand to one million of bricks. The 

 kiln ground is kept clean, and the bricks wheeled in readily from the 

 drying floor ; while setting the kiln and the casing being taken off 

 after burning, the kiln is easy of access by teams to take away the 

 bricks. This plan of casing kilns is much preferred to that of build- 

 ing thick, heavy, stationary walls. The quantity of brick made in 

 one season (about five months) per each man employed is about one 

 hundred and twenty five-thousand ; in all cases where the stock breaks 

 up, in a hard, lumpy state, it should, if practicable, be dried and 

 shoveled into water ; the water buoys it up, and causes the lumps to 

 dissolve; the effect is entirely different from that of putting the stock 

 in first and then adding the water, but when the stock is soft in the 

 bank like putty it should be put into the pit without drying, 

 and the water then added. Drying the stock produces a similar ef- 

 fect to that of freezing ; the sand used in the stock is added after it 

 is soaked ; while tempering, the quantity of coal dust from three pecks 

 to one bushel per thousand, varying according to the stock. The use 

 of coal dust or fine coal (worked into the stock the same as sand) has 

 become universal on the Hudson river. It has been thought by some 

 who were unacquainted with the matter, that the use of fine coal in 

 this manner must injure the brick, leave them porous, &c. This, 

 however, is a mistake, the quantity in each brick is very small. 

 When brick receive that degree of heat necessary to vitrify, or put 

 the stony nature into them, (though the heat has before expanded 

 them) they contract, causing the kiln to settle ; the coal being a mi- 

 neral unites with and enters into the stock, and the contraction closes 

 the pores; the brick are stronger and more solid than those made 

 without coal, but it requires great skill in burning. No one ought to 

 undertake to burn brick in this way without at first serving an ap- 

 prenticeship at the business ; vast quantities of brick were spoiled in 

 learning the art ; it is a trade by itself. I shall refrain from giving a 

 description of the process, for the reason that it might induce some 

 persons to try the experiment, and without a practical knowledge a 

 failure would ensue and perhaps a heavy loss. The use of coal dust 

 saves nearly one-half of the fuel; the time of burning about four and 

 a half days. A very large yard has been established at Cambridge, 

 Mass., on the plan I have here marked out. One hundred thousand 

 bricks will be made on it daily next season. The process of making 

 brick in every section of the country north of Pennsylvania, partakes 

 more or less of the plan I have here laid down. 



In Philadelphia, and throughout Pennsylvania, and the southern 

 States generally, the process is very diff'erent. In Philadelphia, the 

 stock is composed of clay loam, and silicious earth heavily impreg- 

 nated with oxide of iron; the stock is tempered by manual labor with 

 a spade or shovel ; it is shoveled into a heap on the ground at the 

 place where it is dug ; water being poured on, it is left to stand over 

 night ; the next day made into mortar ; a day's work to temper the 

 mortar for two thousand three hundred — from thence it is wheel- 

 ed by another man, sometimes a long distance to the floor for drying, 

 a narrow space of ground, adjoining which is a shed, under which 



