GROUND-WOOD PULP. 48 
have been better. The fact that the majority of the tests were 
made after the wood had seasoned from one to one and one-half 
years might also account for the more satisfactory operation of the 
material. The yield was approximately 2,060 pounds per hundred 
cubic feet of solid rossed wood. 
Fie 31.—Western hemlock ( Tsuga heterophylla). 
Jack pine (Pinus divaricata) yields a very good pulp when ground 
with a rather dull stone, necessitating, of course, a high power con- 
sumption. The pulp produced at a consumption of from 90 to 100 
horsepower per ton for 24 hours compares favorably with white 
spruce pulp made with a somewhat lower power consumption. In 
