THE IDENTIFICATION OF MAHOGANY 

 By Arthur Koehler 



Forest Products Laboratory, U. S. Forest Service 



Considerable information on the characteristics of mahogany and 

 its substitutes has been made available comparatively recently through 

 the efforts of a number of investigators. This was principally an out- 

 come of the war, as this information was needed in connection with 

 the manufacture of airplane propellers. In the January issue of the 

 Journal of Forestry, Professor Record of Yale had a key for 

 identifying some 40 species of mahogany-like woods. An article enti- 

 tled "Mahogany and the Recognition of Some of the Different Kinds 

 by Microscopic Characteristics," by Professor Henry H. Dixon of 

 Trinity College, Ireland, appeared in the Scientific Proceedings of the 

 Royal Dublin Society for December, 1918. At about the sanie time 

 the writer prepared for distribution among Government inspectors, 

 ofificials and manufacturers of mahogany products, a mimeographed 

 article, "The Identification of True Mahogany and Certain So-called 

 Mahoganies." 



Record includes 11 species not mentioned in Mell's "True Ma- 

 hogany" (U. S. D. A. Bui. 474) as being called or similar to Szvietenia 

 mahagoni, and Dixon adds 19 other species, bringing the total of 

 mahogany-like woods up to 97. 



It is with Dixon's paper that this review is principally concerned. 

 The writer wishes to take exception particularly to his definition of 

 mahogany, which follows : 



"We may, then, define as mahogany all red or red-brown timbers in 

 which the fibers of adjacent layers cross each other obliquely, and so- 

 give rise to a play of light and shade on longitudinal surfaces ('roe'), 

 greatly emphasizing and enhancing the figure. This causes the wood 

 to be difficult to 'clean.' and confers on it a freedom from splitting 

 and warping." 



Few woods fit this definition better than red gum except that the 

 gum has a tendency to warp (as have most other woods with inter- 

 locked grain, mahogany apparently being an exception). Not many 

 consumers of wood, and probably few dealers and manufacturers,. 



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