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‘the expansion and contraction. occasioned by the heating and cooling, 
_ wonld soon destroy the walls, however strong. The inner-wall should 
> = . 
1. Front elevation. 
A B C D, timbers 12 by 8 inches, each log projecting 4 inches over the other. 
KE, ) Janks 12 by 2} inches, extending through the wall. 
be a foot thick, and constructed of materials indestructible by heat, 
such as fire-brick, or soapstone—the latter being preferable. One thus 
lined, which [ have had in use for many years, is seemingly as perfect 
as when built; and it is not even a pure soapstone, but bastard,” 
found in many places in the mountains of Pennsylvania and elsewhere. 
The iron bars of the grate should be narrower on the top than on the 
bottom, and they should rest loosely on cross-bars, so that they may 
be shoved to one side or the other, and allow the lime to pass through, 
as may be needed, when taken out. The hinder part of the grate should 
be elevated, so as to throw the lime forward as it is taken out at the 
front. This is either a draw-kiln, from which you may take the lime as 
