160 FARM APPLIANCES. 



conical heap above ground. Large stones are used to 

 make an arch under the heap, and the cavity below the 

 arch is filled with fuel. Immediately above the arch is 

 placed a layer of dry wood, then a layer of lime-stones, next 

 a layer of wood, and so on until the heap is completed. 

 The stones are laid rather loosely, and the entire heap is 

 covered with earth to the depth of at least a foot, to re- 

 tain the heat, leaving an opening at the top for the es- 

 cape of smoke. It will pay to insert a short sheet-iron 

 chimney in this opening, to increase the draft, as a hot 

 fire is needed. The draft is regulated by opening or 

 closing the doorway under the arch. Do not disturb the 

 heap until it is perfectly cool, and if the lime is not to 

 be used at once, it should be protected from rain by a 

 roof, and from surface water by erecting a low bank 

 about it. Where limestone boulders can be gathered in 

 sufficient quantities, the cost of lime will be very little, 

 and even when the rock must be quarried, burning lime 

 will frequently yield handsome returns when the weather 

 does not admit of regular farm work. 



VALUE OF GAS LIME. 



Gas lime, as its name indicates, is a product of gas 

 works. Quick lime is spread in large boxes, called puri- 

 fiers ; the gas passes through these, and coming in con- 

 tact with the lime is deprived of its impurities, especially 

 the sulphur it contains. When the lime ceases to act, it 

 is thrown out and replaced by a fresh supply. Gas lime 

 smells strongly of sulphur, and contains the sulphides of 

 ammonia and of lime. These are fatal to plant life, and 

 before it can be used as a fertilizer, the lime must be ex- 

 posed to the air for some weeks. When unpleasant 

 odors are no longer perceptible, the gas lime may be used 

 in the same manner as ordinary lime. It still consists 



