17 



That is to say. t hat a, instead of being a constant, as usually assumed. 



I 



has been found to be a rectilinear function of 



7 



10 12 14 16 



18 



20 22 24 26 



28 



30 32 



Flo. 1.— Diagram showing the relation between the coefficient of crushing endwise strength and the 

 ratio of length to least width of solid timber columns of longleai pine. 



This equation, transformed, becomes 



700 + 15c I 



/= F + 700 + 15,+ c* Wheie C = d 



The values in Table VI have been computed by this formula. 

 25665— No. 1l'— 02 2 



