24 BULLETIN 67, U. S. DEPARTMENT OF AGEICULTURE. 



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e 6 e Z 1l5£a20^l9d(rill l » I6 9 

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Le^en// - 



A — fiocLdut o/ RupLtze lor polai 



8 ~ fUtec iJicejj a2 C/asliC tunji Im poias 



C ~ Mcdiilcu (J Riy^iuce iac srruill _cJleajr ieamj cui {cam. lasJe^d polos 



-Relation of fiber stress of poles and modulus of rupture of small, clear beams cut from 

 them to the modulus of rupture of poles. 



