26 BULLETIN 72, U. S. DEPARTMENT OF AGRICULTURE. 



that the high gravity of the wood and the resultant high yield of 

 pulp per cord give longleaf pine an advantage possessed by few, if 

 any, other commercially important woods suitable for pulp making. 



The autoclave tests indicate that there should be a certain com- 

 bination of values for the variable cooking conditions which will 

 result in the most economical method of operation. However, 

 other factors than the variables thus far investigated must be taken 

 into consideration in determining what this combination is. For 

 example, the proper degree to which a pulp must be cooked will 

 depend partly upon the cost of the beater treatment. With cheap 

 power for beating, the pulp need not be so severely cooked as when 

 the cost of power is high. The best concentrations and proportions 

 of chemicals in the digester liquors will likewise depend upon the 

 efficiency of the recovery system and the method of operating it. 



o 



WASHINGTON : GOVERNMENT PRINTING OFFICE : 1914 



