238 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1941 



conveying ammunition from boxes to machine guns, plastic face pieces 

 and lenses for gas masks, molded parts for shells, and the use of 

 synthetic fibers in parachutes. 



Resin-bonded plywood in 1940 expanded into many industrial fields. 

 Refrigerator cars constructed largely of this material are said to be 

 6,000 pounds lighter than the previously used type and to provide 

 an economy in fabrication costs because of an 86.5 percent reduction 

 in the number of joints. Simplification of small-boat construction 

 and improved weather-resistant decking and planking for larger 

 craft have also marked the introduction of this material into the 

 shipbuilding industry. The use of laminated plastic for bearings 

 and cams in high-speed industrial machinery was further extended 

 during 1940. Jigs and fixtures made of laminated plastic represent 

 a new development for light milling operations. Laminated sheets, 

 rods, bars, and tubes of various cross sections and lengths are avail- 

 able so that these tools can be produced with very little machining. 



Progress in plastics applications during 1940 may be summed up 

 by noting that many branches of industry, such as the automotive, 

 radio, refrigerator, and mechanical handling fields, which had pre- 

 viously made extensive use of plastics, added new molded parts to 

 their products, and that other manufacturers of consumer goods, 

 faced with military priorities for light and heavy metals, turned to 

 the synthetic plastics as readily available and suitable materials for 

 structural parts of many types of equipment. 



