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POPULAR SCIENCE MONTHLY. 



by a separate chain. In Fig. 6 the sprocket wheel and chain are well 

 defined, and forward of these can be seen the outline of the casing en- 

 closing the gearing. 



Fig. 8 shows another European design, in which a variable-speed 



Fig. 8. General View of Renault Voiturette. 



gear is used. The plan of the truck, showing the general arrangement 

 of the mechanism, is presented in Fig. 9, and the details of the variable- 

 speed gear are shown in Fig. 10. The motor is located at A, and through 

 a friction clutch B, and the variable speed gear C, it rotates the shaft 77, 

 which runs lengthwise of the vehicle. Motion is imparted to the hind 

 axle by means of bevel gears contained within the casing D. The large 



Fig. 9. Plan of the Trick. 



In.. 10. Vakiable Speed Gear. 



bevel gear on the axle is of the differential type, so as to drive the wheels 

 H R at the proper velocities. 



When a high speed is desired, the variable speed gear, Fig. 10, is set 

 so that shaft M drives N direct, the clutch at E being moved so as to 

 interlock. N is the end of shaft //, so that with this connection the 

 bevel pinion, which meshes into the axle gear at D, revolves at the same 

 velocity as the motor shaft. By moving the handle V, Fig. 9, to the 



