202 



FOREST PRODUCTS 



They are heated in a manner similar to the round retorts, that is, by 

 means of a fire box underneath, although there may be fire boxes at one 

 or both ends, and the fuel in the Pennsylvania and southern New York 

 regions is usually either coal or natural gas. In the Delaware County 

 section the fuel consists of coal from the Scranton region. The vapors 

 pass out from one or two large openings at the side or at the end and are 

 condensed through a large copper condenser. The process of distillation 

 requires from twenty-two to twenty-four hours with the o'ven retorts, and 

 when the doors are unsealed and opened a .cable is attached to the first 



Photograph by Nelson C. Brown. 



FIG. 57. The wood distillation plant of the Cobbs-Mitchell-Co. at Cadillac, Michigan, 

 showing the oven house, the first and second sets of 52-ft. cooling ovens and on the left 

 the trucks of charcoal which have just been released from the second cooling ovens. 

 This plant has a capacity of 96 cords per day. Hardwood sawmill and woods waste is 

 used. 



car and they are drawn from the ovens directly into the first cooling oven, 

 which is of the same type of construction and shape as the heating oven. 

 The capacities of the oven plants vary with the number and size of the 

 ovens. There are some oven plants that now consume as high as 200 

 cords a day in the Lake States. The largest plant in New York State 

 has eight ovens; it consumes 80 cords of wood per day and has an 

 annual capacity of 24,000 cords. 



