542 



AUXILIARY FOREST INDUSTRIES. 



till the upper props are required ; then the dome is com- 

 pletely plastered, though at first only thinly so as to allow 

 the gases to escape. 



The kiln is kindled by filling lightly the still open Hue with 

 short thin pieces of split wood, on which comes a layer of 



glowing charcoal. As soon 

 as the kindling material has 

 thoroughly caught fire, fresh 

 charcoal is from time to time 

 heaped on. The split wood 

 which for a time supports the 

 charcoal burns completely, 

 and the glowing charcoal falls 

 to the bottom of the flue. 

 The flue is then filled with 

 charcoal, which is pressed 

 down, and the kindling cavity 

 also filled with a heap of charcoal. After a few hours 

 the flue is burned through from below, and must be 

 repeatedly filled, as long as the glowing charcoal con- 

 tinues to sink. When all danger of explosion is over and 



Fig. 315. Plank-supports of 

 Alpine kiln. 



Fig. 316. Prop supports of Alpine kiln, 



the wood in the dome is thoroughly kindled, it is covered 

 with paste, and the burning conducted henceforth as in 

 ordinary kilns. 



In Alpine kilns the filling which has just been described 

 must be most carefully conducted ; as a rule, only charcoal is 

 used for the purpose. 



