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so as to be only moderately hardened by the temperature of the ground. 

 (D.) The filling between the walls is composed of short dry shaving?, 

 chaff, or other poor conductor.*, 3J feet thick, on the bottom and sides. 

 (C.) Joist for plank floor, 3^ feet above the ground. The floor is 

 made level throughout. (F.) Chloride of calcium, or di-ied waste- 

 bittern, from salt works, spread on every part of the floor of the pre- 



serving room, to absorb moisture. (I. I.) Air-tight casings, made of 

 common sheet-iron No. 2G ; the edges thickly painted, and nailed to 

 upright studding. The outer casing in some houses is made of brick. 

 The inside of the brick wall is covered with roofing cement, or pitch, or 

 some other air-tight coating. (K. K.) Doors G or 8 inches thick. 



