Bui. 101, U. S. Dept. of Agriculture. 



Plate IV. 





n 



Fig. 1— Form of Specimens for Pene- 

 trance Tests and Manner of Saw- 

 ing to Determine Penetrations. 



Fig. 2.— Longleaf Pine Heartwood, 

 Treated in Cylinder. 



The left half of this specimen shows the usual 

 appearance of creosoted heartwood pine; 

 the dark bands are heavily treated summer- 

 wood and the lighter ones are treated spring- 

 wood. On the right side both summerwood 

 and springwood are evenly treated. No 

 difference could be detected in the wood 

 with the microscope that might have caused 

 a difference in the treatment. The right 

 side is toward the pith of the tree. 



