20 



BULLETIN 607, U. S. DEPARTMENT OF AGRICULTURE. 



penetration. Thus, in figure 11, the penetration at 210° F. was 

 about two and one-half times that at 160° F., while the absorption 



PENETRANCE TESTS. 

 (Data in Table 21.) 















































3 



































































































































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a. 



















































































































































































 0.07 























































































ojjg 



















































































«0.05 



ffi 



















































































9SORPTION- 

































































































































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0.02 























































































0.01 























































































0.00 













































1 



50 





r 



TO 





ii 



10 





1 



30 





2 



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2 



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20 







TEMPERATURE— DEGREES FAR. 



FIG. 12.— The relation between absorptions and penetrations into longleaf pine using a mixture of 25 per 

 cent creosote No. 4 and 75 per cent tar No. 5 at different treating temperatures. Time of treatment, 1 hour; 

 pressure, 200 pounds per square inch. 



was 1.6 greater. In figure 12, with a mixture containing 75 per cent 

 of tar, the penetration at 220° F. was also two and one-half times that 

 at 160° F., while the absorption was twice as great. 



