62 OUR VANISHING FORESTS 



not waste but new wood direct from the forest is 

 utilized. The old problem of forest exhaustion and 

 distribution thus adds about a million and a half 

 cords a year to the nation's wood bill. 



The distillation of hard and soft woods is 

 handled by different methods. The modern hard- 

 wood process, devolving from an original pit or 

 brick kiln method, uses batteries of metal oven- 

 retorts heated by coal or coke. The gases which 

 are thrown off while the wood is charring and later 

 cooling are collected with very little loss, and are 

 then further distilled for the manufacture of the 

 extremely valuable products upon which the industry 

 is founded. The first of these is acetate of lime, a 

 chemical used very largely in the textile and leather 

 industries. During the war it was in great demand 

 for the making of high explosives. A better known 

 product is wood alcohol, used chiefly in paint and 

 varnish manufacture, but also in the preparation of 

 dyes, photograph films, and even in stiffening hats. 

 We know it best as a fuel for small lamps and, 

 when taken internally, as a deadly poison. The 

 wood-tar residue is generally used as fuel in chemi- 

 cal manufacture. Nevertheless, under the name of 

 wood-creosote, it has considerable medicinal value 

 and there is some likelihood that, if the process of 

 manufacture could be sufficiently cheapened, a broad 



