140 FIRST BOOK OF FORESTEY 



decay under such circumstances, and perishable woods, 

 like beech, maple, and birch, will lose as much as twenty- 

 five per cent of their value in one year. 



Pw//; Wood. — In the vicinity of pulp mills, soft woods 

 like spruce, poplar, aspen, balsam, and also hemlock, pine, 

 basswood, tulip poplar, and others, can usually be sold to 

 good advantage. 



Since the pulp mill can use small pieces, down to two 

 feet in length and four inches in diameter, a great deal of 

 the sapling material, which should be taken out in thin- 

 nings, can thus be utilized. 



For pulp the wood should be green, sound, straight, 

 and as free from knots as possible ; in other words, just 

 such w^ood as grows in a close stand, where the trees are 

 obliged to clean early. 



Pulp wood is sold by the cord, and when rossed, i.e., 

 the bark taken off, it sells as high as ten dollars per cord. 



Pulp is made from the wood in two distinct ways, — 

 by grinding, and by maceration with chemicals. In mak- 

 ing " ground " pulp the blocks of wood are held and pressed 

 by a machine against a large grindstone on which a small 

 stream of water is jDlaying all the time. In this way the 

 fine particles of wood which are ground away are carried 

 off by the water into large vats. 



This coarse, mushy wood pulp is then sifted, washed, 

 and stirred, and finally passes over an endless piece of 

 cloth, where it is freed from the water. After this it may 



