16 



BULLETIN 343, U. S. DEPARTMENT OF AGRICULTURE. 



liquor, and for that reason the amount of the materials can not be 

 expressed in quantity per cord. 



It will be noted that two samples were analyzed, one of which was 

 a residue from evaporation of a condensed liquor and the other a 

 sample of the liquor from another cook. The woods steamed were a 























































































































120 



















































































































E no 



a 

















































































( 



>— 

































X „ 



S 100 



















































































































X 



h 90 



















































































































U 



0- on 



























































£2 

 14 

 * 



O 























































































































0. * w 



u 



























































c 



























































X 



Sift 















































































































































































4 S 6 7 8 



HOURS OF STEAMING 



10 



II 12 



13 14 



Fig. 8. — Effect of duration of steaming on power consumption per ton of pulp. (Spruce runs 114-119, 



inclusive.) 



mixture of jack pine and tamarack in the ratio of 67 per cent of the 

 former to 33 per cent of the latter. 





Residue 

 from evapo- 

 ration of 

 liquor. 



Sample 

 of liquor. 





Residue 

 from evapo- 

 ration of 

 liquor. 



Sample 

 of liquor. 





Per cent. 



Per cent. 



2.05 



1.95 



.83 



. .092 



Ash 



Per cent. 

 9.85 

 5.71 

 1.41 

 4.31 



Per cent. 

 0.049 





70.10 

 15.89 

 13.60 





.162 







.042 







97.95 









The total and soluble solids and tannin were determined accord- 

 ing to the methods outlined by the American Leather Chemists' 

 Association. 



The boiling or steaming of woods results in the formation of a 

 natural size from the wood substance or some of its constituents. 

 This sizing action is particularly noticeable in the production of 

 pulps from the hardwoods — birch and aspen — which are not pitchy. 

 All paper produced from cooked woods, pulped by the mechanical 

 process, show the characteristic water-resistance qualities and hard- 

 ness of hard sized papers. 



