238 



FOREST PRODUCTS 



York disclosed the average yield of 42.7 bushels of charcoal per cord of 

 wood, which consisted largely of beech, birch and maple. 1 



Experiments have shown that the number of pounds of dry charcoal 

 per bushel varies from 32.89 for shellbark hickory, to 27.26 for beech, 

 21.10 for white oak and 17.52 for longleaf pine. The same experiments 

 demonstrated that the weight of charcoal produced per cord of air-dry 

 wood also varied considerably. A cord of shellbark hickory produced 

 1172 lb., beech, 635 Ib; white oak, 825 Ib, and longleaf pine, 585 Ib. 



The table on page 239 shows the yields from a variety of American 

 woods, together with their specific gravity, weight of wood, and a num- 

 ber of other related facts. 2 The specific gravities do not agree with those 

 commonly accepted at the present time, but the correlated facts are inter- 

 esting. 



In Europe, where the industry has been most highly developed, 

 investigations carried on by Bergil disclosed the following yields, ex- 

 pressed in percentages of weight and volume. The species mentioned 

 are very similar in properties and characteristics to those of similar name 

 in the American forests. 



YIELD OF VARIOUS EUROPEAN SPECIES IN CHARCOAL DERIVED BY THE 



OPEN-PIT METHOD 



PROCESSES USED 



The process of manufacture of charcoal by the open-pit method 

 consists generally of the following operation: Billets of wood from 2 to 4 

 ft. or more in length and from 2 to 6 in. in diameter, are piled on end in a 

 conical form. There may be from 10 to 35 cords or more to the pile, and 



1 See the " Hardward Distillation Industry in New York," by Nelson C. Brown, New 

 York State College of Forestry, Syracuse, New York, 1916. 



2 Taken from experiments by Marcus Ball, Philadelphia. 



