FOREST SERTICE. 



HENBY S. GRAVES, Forester. 

 ALBERT P. POTTER, Associate Forester. 

 HERBERT A. SMITH, Editor. 



BRANCH OF PRODUCTS. 



MCGARVEY CLINE, Director, Forest Products Laboratory, In Charge. 

 HOWARD F. WEISS, Assistant Director. 



Timber Physics: 



HARRY D. TIEMANN, Engineer in Forest Products, In Charge. 

 FREDERICK DUNLAP, Forest Assistant. 

 OLLISON CRAIG, Assistant Engineer in Forest Products. 

 ELOISE GERRY, Microscopist. 



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ADDITIONAL COPIES of this publication 

 -A- may be procured from the SUPERINTEND- 

 ENT OF DOCUMENTS, Government Printing 

 Office, Washington, D. C. at 5 cents per copy. 



