GROUND-WOOD PULP. 

 EXPERIMENTAL MANUFACTURE OF PAPER. 



51 



A limited amount of paper (waterleaf) was made experimentally 

 at the Madison laboratory from the various pulps and tested for 

 strength and color. In every case the conditions of manufacture 

 were identical, and no coloring matter was added to any of the pulps 

 in the beater. The paper machine used was too small to permit of 



Fig. 39.— Engelmann spruce (Picea engelmanni). 



reliable data being obtained upon such points as operation of the 

 pulp on the machine, calendering, and the like. 



In the matter of color the various wood fibers (unsteamed) may 

 be arranged in the order given below, the basis bemg the number of 

 parts of black which each sample contained, that with the smallest 

 number ranking first. It should be remembered that the arrange- 

 ment is made as the result of tests on many different samples of 

 paper from the same wood, rather than on the particular samples 



