EFFECT OF SPIRAL GRAIN ON STRENGTH 



741 



The term "cross grain" covers all instances in which the direction of 

 the wood fibers deviates from straightness or is not parallel to the 

 axis of the piece. Considering the fact that the trunk of a tree is made 



Fig. 1. — Effect of spiral and diagonal grain 

 r--.odulus of rupture, and modulus of elasticity in 



on fiber stress at elastic limit, 

 static bending. White ash. 



