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Show Industrial digest section of American Industries In-dustries (New York, July), of an article contributed originally to the Hardwood Record (Chicago). According to this paper, pa-per, the propellers of British aeroplanes are now chiefly made of American walnut. wal-nut. We read : "That important use of black walnut wal-nut is the latest, and it is likely to be a large one if the war continues to spread and is continued long. The wood is not so strong as some others, including hickory hick-ory and maple, but it is probably strong-' er, weight for weight, than any other wood suitable for propellers. - . . Walnut is also a highly elastic wood, and that quality is needed In a propeller, which must run at high speed and under enormous strain while transmitting perhaps per-haps 100 horsepower from the engine to the air. "Still another quality is peculiarly valuable val-uable in the exacting service which an aeroplane must do. Walnut: does not splinter when struck. If it breaks, at all, it breaks clean. That quality comes in good play when a warplane is under Eire. The propeller Is particularly vulnerable, because it cannot be protected by armor or any other device, but it is a shining mark for every bullet aimed. If struck, the bullet passes through, leaving only a small bole; but if the propeller is of wood liable" to split or splinter, a bullet might tear away a piece of sufficient size to cripple the machine. "Walnut, after being well seasoned, has little disposition to shrink and swell. The propeller Is exposed to rain, snow, fog and dampness of every kind, but walnut holds its form and runs true. k . "American ash, hickory and spruce are the chief woods in the frames of British aeroplanes. Hickory goes across the sea In the form of long logs, straight and faultless. Those now being shipped for the British war department cost $60 a thousand feet on this side, and the freight across the sea costs $100 more. The freight is thus seen to amount to much more than the hickory costs in New York; but so urgent is the need that the British government willingly pays the freight. 1 , "The ash used is of a correspondingly higli grade, and. like hickory, it serves as frame material, forming the skeleton over which the canvas is stretched. "Still another wood ranks remarkably high in aeroplane work. The British call it "silver spruce, but it Is the West Virginia Vir-ginia red spruce. For aeroplanes it has been pronounced superior to every other spruce of the known world, even going above the gigantic Sitka spruce of the northern Pacific coast. "The typical West Virginia spruce grows in thin ground, often upon vast beds of broken stone covered with moss, and with scarcely any visible soil. The best is found at altitudes of 3500 to 4500 feet on the mountains surrounding the interlocking sources of the Potomac, Kanawha Kan-awha and Monongahela rivers. The growth is slow, the tree trunks straight as plummets, and with limbs at the extreme ex-treme tops. The wood Is straight grained and remarkably free from knots and other oth-er imperfections." Li terary Digest. Wisccllanii 1 ; American Woods for the War. The available supply ot European walnut wal-nut for gun stocks Is exhausted, and the warring nations tire looking for more. But even more urgent Is the demand for this wood for aeroplane propeller blades and other parts of the aircraft exposed to hostile gunfire. We are told that a representative of the British government i recently visited Chicago to purchase Mack ' walnut and other American hardwoods. . especially for use in military aeroplanes. The daily pre?s even reports that Kansas Kan-sas is teing denuded of her walnut orchards or-chards for this purrse. cmr quotations quota-tions are from an abstract, made for the |