THE COMMON METHOD. 703 



broom, heather, &c. Thin sods placed like tiles overlapping 

 one another form the densest covering, and leaves or silver-fir 

 branches also aiford a dense covering. The covering is first 

 applied 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 humus maj^ be substituted. These substances should 

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

 water added to form a stiff" paste, which must have sufficient 

 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 first applied at the foot of the kiln, the 

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

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

 there than below. Sometimes a ring is left uncovered just 

 below the dome of the kiln, this is covered with paste when 

 there is no longer any danger of bursting. "When the kiln is 

 kindled from below, its lower portion is at first frequently left 

 free from the outer covering, which is applied gradually as the 

 burning proceeds ; usually, however, the kiln is covered with 

 paste before being fired. 



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 usually made 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. Kindlinrj and Burning the Kiln. 



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

 torch made of resinous wood-splinters through the kindling- 

 passage to the kindling material at the bottom of the flue, 

 which is thus fired. When kindled from above a little fire is 

 lighted at the top of the flue. The kiln is always fired on a 

 still morning before daybreak, sometimes whilst its base is open 



