UTILIZATION OF ASH. 



37 



PROFESSIONAL, AND SCIENTIFIC INSTRUMENTS. 



Ash is used for tools and instruments, especially for carpenter's 

 tools. More is used for this purpose in New Jersey than elsewhere. 

 The average price paid is high — about $62 per 1,000 board feet. 



AEROPLANES.^ 



Ash is the second most important wood used in aeroplanes. The 

 great bulk of the AYood used is spruce from the Pacific coast and 

 West Virginia. The essential qualities needed in wood for aero- 

 planes are straightness of gTain, strength, absolute freedom from 

 hidden defects, lightness (in comparison with strength), and ability 

 to stand extreme stress. Ash is used in framework, main outriggers 

 on which the canvas is stretched, uprights bearing the engine or 

 forming the engine bed, skids (on the upright, cumdng ends of which 

 the alighting wheels are fixed) , rudders, and propeller blades. For 

 framework, outriggers, and uprights straightness of grain and 

 strength are the essential qualities needed, which usually can be 

 best supplied by rapid-growing, comparatively young growth, from 

 75 to 150 years old. For propeller blades, for which ash is very 

 largely used, the quality desired, in addition to streng-th in com- 

 parison with weight, is ability of the wood to hold its shape, which 

 is best supplied by old-growth ash. Propeller blades are made 

 from laminated blocks consisting of several layers of different kinds 

 of wood glued and nailed together. An excellent combination is 

 said to be a middle layer of ash with spruce on either side, then 

 layers of mahogany on the spruce, and thin layers of ash on the 

 outside.^ Engine blocks and frame ribs are also often laminated 

 in construction, spruce and ash being combined to divide the 

 stress. 



The average price for ash lumber used for aeroplanes is very high, 

 about $G5 per 1,000 board feet, and there is much waste in utiliza- 

 tion. A Chicago firm in 1912 paid $180 for 600 feet of specially 

 sawed ash, or at the rate of $300 per 1,000, feet, which is probably a 

 record price for ash lumber. 



EXPORT. 



From five to seven million feet of ash logs are exported annually 

 to Europe, chiefly green ash from the South Atlantic and Gulf 

 States. Export dealers pay from $30 to $40 per 1,000 board feet 



i Information supplied by J. T. Harris, Office of Industrial Investigations, Forest 

 Service. 



2 Great trouble has been experienced from the splitting and checking of wooden 

 aeroplane propellers, when made from laminated blocks either of a single material or 

 of dlf¥erent woods. *his can best be prevented by use of thoroughly air-seasoned 

 woods, and by keeping propellers out of doors at all times, or by giving them a coating 

 of ijaraffin to prevent the entrance of moisture. 



