10 BULLETIN 77, U. S. DEPARTMENT OF AGRICULTURE. 



increased the strength and stiffness of the wood but decreased its 

 toughness. 



INCH-POUNDS PER CUBIC INCH 



Fig. 4.— Relation of unit strength of 10-foot round beams to condition; based on average values of the 



three sizes tested. 



In comparing fire-killed and green material, the grade of both, in 

 regard to ordinary defects, should be taken into consideration. The 



