© Committee on Public Information 



America's women are enlisted in the air service of" their country 



Not only in munitions factories does the skilled workwoman find her opportunity for war 

 service. Filing fittings for the wing spars of airplanes is this girl's task. 



the difficulty will begin to appear. Let 

 me explain this in detail. 



The ideal trees for airplane spruce are 

 the fine old patriarchs, scarce enough at 

 best, which have a girth of about 14 feet 

 and run up 160 feet without a branch. 

 Now when this splendid wood is cut 52 

 per cent is thrown out at once — the part 

 in the heart where the grain is too cir- 

 cular and the part at the circumference 

 where the grain is too coarse. Another 

 10 per cent is culled out for various rea- 

 sons and another 7^ per cent lost in kiln 

 shrinkage. This leaves us less than one- 

 third of our original wood for further 

 selection. 



Of this third, however, only a small 

 proportion is fit for the more delicate 

 work. Less than 1 per cent of it has the 

 necessary length and strength for aile- 

 rons ; 2.3 per cent is fit for the wing 

 beams ; 4.6 per cent for the long struts, 

 and the same for the landing gear. The 

 balance can only be used for ribs and the 

 smaller fittings. 



straining America's lumber 

 resources 



These figures show why America's vast 

 lumber resources are being strained to 

 the limit to build our air fleet. They ex- 

 plain also why it has been necessary for 



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