USE OP CHARCOAL IN IRON MANUFACTURE. 



125 



a wide area of country, and may doubtless be received as fairly repre- 

 senting the average experience of the country around them : 



Summary of returns from charcoal furnaces and forges. 



* For making one ton of slabs and blooms. 

 X For one ton of blooms or billets. 



t Wrought iron. 



§ Seventy-five to eighty for wrought iron. 



Ifotes concerning kinds and qualities of wood used for making charcoal, yield, reneical, and 

 vianagenient of woodlands. 



[The numbers of these notes correspond with those in the first column of the preceding table.] 



1. Pine and some hard woods used. Oak makes the best charcoal that we get. The 

 yield is about 1,500 bushels to the acre, and 20,000 acres are sufficient for a permanent 

 supply. Lauds cut over are reserved for growing another crop, and the furnace now 

 has 4,000 acres of young trees. When 8 years old they should be thinned out, getting 

 10 per cent, and leaving the rest in better condition for growing. Some attempts have 

 been made at planting black walnuts around pasture-fields, but to no great extent. 

 Charcoal burnt in open air better than in kilns, although the percentage of yield is less. 



2. Oak and hickory regarded the best kinds of timber for making hard carboniferous 

 coal. Gum and poplar make soft coal, of much less value. Charcoal made under soil 



