United States Naval Institute proceedings, Volume 45 P. 1929 Posted on Tuesday, June 27th, 2017 and is filed under News
Lignum-vitae, The Vital Wood.—The propeller shaft of every battleship, every destroyer, every transport, in fact, every large steamship, revolves in a wooden bearing at the stern end. Of all the thousands of woods in the world, true lignum-vitae, a native of the West Indies and certain other parts of tropical America, is the only one that has been found equal to this exacting service. The peculiar properties which so well fit lignum-vitae for the purpose are due to the arrangement of the fibers and the resincontent of the sap cells. The fibers never run straight up and down the log, but weave back and forth in a serpentine manner that cross and crisscross like the corded fabric of an automobile tire. The result is a material of extreme tenacity and toughness. When the sap cells cease to function, their every nook and cranny become filled with a resin which is about a third heavier than water. The result is a material which weights about 80 pounds per cubic foot.
Stern bearings provide the most important use for lignum-vitae but by no means the only one. Formerly it was in great demand for bowling balls, but now only one ball in ten is made of wood. A large quantity of low-grade logs, known as ” cutting-up ” wood, is consumed in the manufacture of rollers for furniture casters. Small round sticks made excellent mallets and fill a large demand, especially in Engand. Another important use is for sheaves of pulleys, and they have been known to last in constant use for 70 years. Another nautical application is for ” dead-eyes,” a small flattish block with a grooved rim to fit in the bight of a rope or encircled by an iron band, pierced with three holes to receive a lanyard, and used to extend the shrouds and stays. Among the miscellaneous uses may be mentioned stencil and chisel blocks, watchmakers’ blocks, mortars and pestles, dowels, golf-club heads, wooden cogs, water wheels and block guides for band saws. In building the Panama Canal, the true lignumvitae made the most serviceable railroad ties that could be obtained. Between 150 and 200 tons of genuine lignum-vitae are used every year in New York for fuel in grate fires. The very dense nature of the wood, together with the heavy resin content, produces a fuel with intense glowing heat and good lasting qualities. This provides one outlet for defective and crooked logs which are found in every shipment—Engineering World, Oct. 1, 1919.