CONTROL OF DECAY IN PULP AND PULP WOOD 51 
pulp is much freer than sound pulp, is brash and brittle, foams 
badly, and tends to stick to the couch and press rolls. The paper 
made from it is considerably darker and much weaker than that 
from sound, and only one-tenth as resistant to ink penetration. 
Ground wood made from decayed wood deteriorates more rapidly 
during storage than that made from sound wood, in spite of the 
apparent destruction of most of the fungi in the original wood during 
the grinding process. 
The most feasible method of controlling deterioration in pulp 
during storage, in addition to the adoption of the precautions against 
infection already indicated, is to introduce an antiseptic into the 
pulp on the wet machine. One hundred and twelve chemicals were 
tested for this purpose. About 3,000 small ground-wood laps and 
1,400 sulphite laps were treated at the laboratory, and about 7,200 
pounds of ground-wood pulp at the mill. The chemicals that best 
filled the requirements for a preservative were borax, boric acid, a 
solution of naphthalene in crude cymene, sodium fluoride, sodium 
dinitrophenolate, and sodium dichromate. 
In the appendix will be found a record of studies, more compre- 
hensive than any hitherto undertaken, of the fungi which inhabit 
pulp. Through these studies it was determined for the first time 
that the principal chemical damage to pulp is attributable to the 
hymenomycete fungi rather than to any of the molds. Sixteen 
hymenomycetes were isolated, but only one was completely identified, 
owing to the great difficulty of developing charactertistic fruit 
bodies in culture. The various fungi are described, and in addition 
to the morphological grouping there is presented a new scheme of 
classification of these fungi which is based on the color reactions of 
pulp infected by them. 
In the appendix is also reported the first extensive investigation 
of the chemical action of fungi on ground- wood pulp. 
