Current Literature. 503 



2,581,674,000 feet; and crossties, poles, cross arms, and wood 

 distillation unknown. The enormous quantity of forest material 

 annually supplied by Arkansas is not exceeded by that of more 

 than two or three other States." 



Part II deals with the timber on the National Forests of 

 Arkansas and the means of purchasing it. It is well written and 

 contains a great deal of definite information of much value to 

 prospective purchasers. Having been prepared by one thoroughly 

 familiar with actual conditions and based upon careful surveys 

 and field studies this part of the bulletin may be considered 

 thoroughly reliable. 



S. J. R. 



Strength Tests of Cross- Arms. By Thomas R. C. Wilson, Cir. 

 204, Forest Products Laboratory Series, U. S. Forest Service, 

 Washington, D. C. 1912, pp. 15. 



Tests were made on 84 six-pin cross-arms 3^ x 4^ inches by 6 

 feet. This number was made up of seven groups and comprised 

 four species: Douglas Fir, Shortleaf pine, longleaf pine, and 

 southern white cedar. 



"In nearly all cases the principal failure was at the first pin- 

 hole from the center, though in many cases the first failure was 

 apparent as a cracking at the center bolt hole. In view of these 

 facts it is recommended that, in grading or selecting arms, par- 

 ticular attention be given to defects near the center or the first 

 pinholes. Knots on the upper sides of the arms at these points 

 are especially to be avoided." 



"All points considered, cross-arms of the species and the dimen- 

 sions tested are strong enough for ordinary use ; with longer arms 

 the strength is relatively of more importance. With the standard 

 6- foot cross-arm, however, the question of strength need not enter 

 into calculations of line construction, except in the rare cases of 

 abrupt change of grade. The ability of the timber to resist decay, 

 and methods of preventing decay, are considerations of greater 

 importance." 



S. J. R. 



