CATALOG OF THE AUTOMOBILE COLLECTION 15 



awarded a prize of $25 for being the oldest machine to cover the line 

 of march under its own power. 



The chassis is characterized by simplicity of construction, which 

 was one of Mr. Knox's objectives in designing a 3- wheeled car. The 

 angle-iron frame is roughly triangular, with the two sides parallel for 

 half their length at the rear, then converging to a point at the front. 

 There is a cross member at the center, where the sides begin to con- 

 verge. The converging sides sweep upward at the front to a motor- 

 cycle type fork in the apex of the triangle. This fork is steered by a 

 tiller pivoted to the upper end of the fork so that it can be moved away 

 from the driver. The rear of the chassis is bolted directly to the bear- 

 ing housings of the rear-axle shafts. 



The hub of the left wheel contains a bevel-gear differential, requiring 

 that the axle shaft of the right wheel pass through the short tubular 

 shaft of the left wheel, with the driving sprocket attached to the inner 

 end of the tubular shaft. The three wheels are each radially wire- 

 spoked, mounting single-tube 28-by-2l^-inch tires. A small mud- 

 guard, turning with the fork, is mounted behind the front wheel. 



The chassis is unsprung, all springing being between the chassis and 

 the body and consisting of three full-elliptic springs, one at each side 

 in the rear and one mounted transversely at the front just behind the 

 fork. 



The engine is a l-cylinder unit of 4i/^-inch bore and 8-inch stroke, 

 rated at 8 horsepower. It is air-cooled by radiation from a large 

 number of small rods projecting from the cylinder. The engine is 

 mounted horizontally in the center of the car, with the crankshaft 

 parallel to the ground and with the cylinder to the rear. It is sup- 

 ported by two metal hangers, one attaching it to the chassis at the back 

 and the other to the cross member in the center. 



The right end of the crankshaft has a small eccentric, which drove a 

 push rod connected to a piston-shaped valve in the valve chamber. A 

 cam, driven at half crankshaft speed, operated another push rod, 

 which actuated a poppet valve located between the combustion chamber 

 and the piston valve. The poppet valve, which remained open for sub- 

 stantially 360° of the turning of the crankshaft, served as both exhaust 

 and intake valve, the piston valve's position determining whether the 

 exhaust or intake manifold was permitted to function. 



The ignition timer is mounted adjacent to the engine camshaft, the 

 cam of the timer being driven by the camshaft. A spark plug is 

 located in the rear of the cylinder. The original spark plug was made 

 in the Knox factory, as were all ball bearings used in the car. 



The portion of the camshaft that drives the cam of the timer is 

 spirally splined and is free to slide with respect to the rotor, advancing 

 or retarding the ignition as it does so. In addition, the cam itself. 



