CHARCOAL-MAKING. 535 



each piece ; these are placed all round the kiln and are very 

 durable. 



The upper supports form a similar circle higher up the kiln, 

 resting on vertical billets or forked pieces of wood; they are 

 placed in position after the kiln is covered. In some districts 

 a third circle of supports is added, but that is not usual. 



The material used for the inner covering of the kiln con- 

 sists of sods, leaves, moss, spruce or silver-fir branches, ferns, 

 rushes, broom, heather, etc. Thin sods placed like tiles over- 

 lapping one another form the densest covering, and leaves or 

 silv<T-iir branches also afford a dense covering. The covering 

 is applied first to the top of the kiln, and should be thick 

 enough to prevent the earth of the outer covering from 

 penetrating through it. 



The outer covering consists of a wet mixture of loamy 

 forest soil and charcoal-dust, the remains of former kilns, for 

 which fresh humu* may bn substituted. These substances 

 should be mixed thoroughly with a hoe, freed from all stones, 

 and water added to form a stiff paste, which must have suffi- 

 cient consistency to serve as a dense coating to the kiln without 

 becoming quite crusted by the heat, remaining soft enough 

 during the burning to yield without cracking to the gradual 

 sinking of the kiln, and to allow the steam to escape. 



This paste is applied first at the foot of the kiln, then 

 the upper row of supports are placed over it and the paste 

 continued up to the top of the kiln, being applied more thickly 

 there than below. The total thickness of the covering is 

 0*7 m. at the base and 0*3 m. at the top, somewhat less round 

 the flue. 



After the kiln is covered, a wind-break is placed around it 

 at a sufficient distance to allow room for the men to manage 

 the kiln ; it is made usually of coniferous branches at least 

 as high as the kiln and fastened to stakes driven into the 

 ground ; this may be dispensed with in thoroughly sheltered 

 places. 



vi. KimHhitj nnil I turn in fi Hit' Kiln. 



If the kiln is kindled from below, one of the burners applies 

 a torch made of resinous wood-splinters through the kindling- 



