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BULLETIN 119, U. S. NATIONAL MUSEUM. 



than ever throughout the period of the World AVar. The effects of 

 the material breakdown in the railway transportation system dur- 

 ing that crisis were considerably allayed by the use of motor trucks 

 moving over long distances, a feat which, prior to that time, had 

 been considered impracticable, so that to-day, following peace-time 

 pursuits, the automobile truck has come to be considered an essential 

 part of the transportation systems of the country. 



Among the mechanical features of the truck of which this model 

 is a reproduction, are the following: 



The frame on which. the body rests is made of pressed steel of 

 channel section and so fitted with cross members and braces as to 

 combine strength and light weight -with the desired flexibility. The 

 frame rests on four semi-elliptical springs that are provided with the 



FIG. 52. RED RIVER C.VRT FOR FREIGHT, 1860. 



necessary bushings and special lubricating devices so that they may 

 be readily and easily lubricated. These, in turn, are supported on 

 the front and rear axles, the front axle being of drop-forged steel 

 of I-beam section. The front wheels are mounted on adjustable 

 tapered roller bearings. The rear axle is of the full-floating Autocar 

 double-reduction gear-driven type, the gear reduction being com- 

 ]Dounded through bevel and spur gears. This reduces the angularity 

 of the propeller shaft, giving straight lines for the transmission of 

 power. 



The rear wheels are mounted on adjustable tapered roller bearings 

 carried on an extension of the axle housing. By this means the 

 rotating parts of the rear axle carry no part of the weight, their 

 only function being to transmit the power to the rear wheels. 



The gasoline four-cylinder engine is located under the driver's 

 seat and is carried on the main frame by means of a three-point 



