CATALOG OF THE MECHANICAL COLLECTIONS 55 



Lubrication is effected by the splash of the cranks in a layer of oil 

 that floats on water in the crankcase. The throws of the crank are 

 formed by bends in the crankshaft. The engine has the manu- 

 facturer's number 2909. 



AUTOMOBILE STEAM ENGINE, 1901 



U.S.N.M. no. 307387 ; original ; gift of Louis S. Clarke ; not illustrated. 



This is a light 2-cylinder, high-pressure, reversible steam engine 

 of the type used in the early Locomobile automobile. 



The engine consists of two vertical double-acting cylinders, 2^^ 

 inches in diameter by 4 inches stroke, cast with a valve chest joining 

 them. An ordinary D -slide valve for each cylinder is operated by 

 a separate Stephenson link motion with two eccentrics for each. A 

 lever and bell crank shifts the two links together. The two cranks 

 are at the extreme ends of the crankshaft and overhang the bearings. 

 The crankshaft and crankpin bearings are provided with roller bear- 

 ings. The power is taken from the engine by a chain from a 12- 

 tooth sprocket at the center of the engine shaft. A boiler feed pump 

 bolted to the frame is operated by a rocking lever actuated by a pin 

 on one cross head. The engine usually operated on a steam pressure 

 of 150 pounds per square inch, though the boiler safety valves were 

 frequently set as high as 240 pounds per square inch. 



STANLEY STEAM AUTOMOBILE ENGINE, c. 1923 



U.S.N.M. no. 310537, original, gift of Laurence J. Hathaway, not illustrated. 



This engine is one of the last type built by the Stanley Automobile 

 Co. It is a 2-cylinder engine of 4-inch bore and 5-inch stroke, 

 nominally rated at 20 horsepower. The engine would actually de- 

 velop 155 horsepower at 600 pounds per square inch pressure, 200° 

 superheat and 80 percent cutoff at 600 revolutions per minute. 



ROTARY STEAM ENGINES 

 BAKER AND BALDWIN ROTARY STEAM ENGINE, 1839 



U.S.N.M. no. 308647 ; original patent model ; transferred from the United States 

 Patent Office; not illustrated. 



This model was submitted with the application for the patent 

 issued to William H. Baker and Samuel H. Baldwin, of Cohoes, 

 N. Y., August 21, 1839, no. 1295. 



This is an early example of a steam engine in which two cams 

 turn together in a closed casing so that steam admitted to the casing 

 will force apart abutments on the cams and cause the cams and 

 the shafts on which they are mounted to turn. This engine may also 

 be used as a pump. 



