REVIEWS 795 



Lignum Vitce: A Study of the Woods of the Zygophyllaccae with 

 Reference to the True Lignum Vitce of Commerce — Its Sources, 

 Properties, Uses, and Substitutes. By S. J. Record, Yale University, 

 School of Forestry, Bui. No. 6 ; 48 pp. New Haven, Conn., 1921. 



This bulletin consists of two parts, written, respectively, from the 

 botanical standpoint and from the commercial standpoint, topped off 

 with a summary and conclusions and an erudite list of references, all 

 of it illustrated by plates. 



In the first part it is made plain that lignum vitae belongs to the 

 family Zygophillaceae, which has but three tree genera: Guaiacum, 

 Porlieria, and Bulnesia — all tropical. Of these the first alone is the 

 true source of the lignum vitse of commerce. It is distributed over the 

 islands and coastal regions of tropical America. Most of the timber 

 comes from Cuba, Haiti, San Domingo, Jamaica, and the Bahamas. 

 At least six species are recognized. Of these G. sanctum is the only 

 one found native in the United States, but, because of its small size, 

 is not of great commercial importance. The wood of G. officinale is 

 probably the chief source of commercial lignum vitse, although this is 

 not yet definitely ascertained. 



The second part reviews the commercial range of lignum vitae. 

 Some idea of its importance may be gained by the fact that 2^ million 

 dollars worth of lignum vitse were imported into the United States in 

 the past 20 years. 



"Lignum vitse is one of the heaviest woods in the world. The weight 

 (oven-dry) per cubic foot of the heartwood is usually between 75 and 

 80 pounds. The wood has been an article of trade for more than four 

 centuries. It was formerly supposed to possess remarkable curative 

 powers but is now little employed in medicine. Its principal uses are 

 for bearings (especially for lining the stern tubes of steamships), 

 •^heaves, caster-wheels, bowling balls, and miscellaneous articles of 

 turnery. During the war there was an unusual demand for this wood 

 m the shipbuilding industry. 



"The properties which make lignum vitse valuable are great density 

 and hardness, extreme toughness, and resistance to wear. The large 

 resin content of the wood acts as a preservative and a natural lubricant, 

 thus making it especially adapted for service under water, as in the 

 case of propeller bushings and water-wheel work. 



