MANUFACTURE OF CHARCOAL IN CHARCOAL KILNS (PITS) 



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Small charcoal pit ready to receive a coating of beech mold and 

 a covering of dirt, preparatory to charring. 



II. The works consists of:- 



(a) Preparation of ground near water 

 by leveling and hoeing the soil, by removing 

 roots and stones, by raising the center of the 

 circle to be occupied by the kiln about 10 inches 

 over its circumference. 



The diameter of the circle is from 15 feet 

 to 30 feet usually. The best soil is loamy sand, 

 which secures proper regulation of the draft. 



The site should be protected from wind. 

 Twigs are woven into a wind screen on the 

 windward side, if necessary. 



(b) Erecting the "Chimney" by placing 

 three or four poles of even height at one foot 

 distance from a central pole, fastening them to 

 the central pole by withes. 



The chimney is cylindrical if kiln is lighted 

 from above, and pyramidal if kiln is lighted 

 from below. The chimney is filled with inflammable substances (dried twigs, charcoal, <&c.). 



(c) Constructing the kiln proper. 



The kiln has a parabolic form. It consists of two or more tiers of billets placed more or less vertic- 

 ally, the bark turned outward, the big end downward, the finest pieces near the chimney and near the 

 circumference, the largest pieces half way between. 



These tiers are topped by a cap, consisting of smaller billets placed slopingly. A cylindrical chimney 

 extends through the cap. A pyramidal chimney is closed by the cap. 



In the latter case a lighting channel is left on the ground running radially on the leeward side from 

 the base of the pyramidal chimney to the circumference. This channel, too, like the chimney, is filled with 

 inflammable material. 



(d) Stuffing all irregularities, interstices, cracks, &c., showing on the outside of the kiln with 

 small kindling. 



(e) Covering the kiln by two draft-proof layers so as to exclude or restrict the admission of air. 



1. The vegetable layer, \'i to Vi foot 

 thick, made of green branches, 

 grass, weeds, leaf mold and moss. 



2. The earth layer, 2 inches to 6 

 inches thick, consisting of loam, 

 charcoal dust, &c. 



If the kiln is lighted from below, a belt 

 about 1 foot high running around the circum- 

 ference on the ground is left without the earth 

 cover until the fire is well started. 



The earth layer and the vegetable layer 

 are thoroughly joined by beating with a paddle. 



In large kilns a wooden frame (the armor) 

 consisting of T sections is used to prevent the 

 cover from sliding down. 



It presents also a safe footing for the 

 attendant to work on. 



Small charcoal pit at the completion of the charring process. 



