54 BULLETIN 173, U. !:>. NATIONAL MUSEUM 



The valves are vertical poppet valves with stems projecting upward 

 from the valve chests. The valve stems are fixed to short arms at- 

 tached to vertical liftmg rods fitted with "long-toe" followers, or 

 cams, which ride upon similar tappet cams operated by eccentric rods 

 from eccentrics on the paddle-wheel shaft. There are two eccentric 

 rods, one on either side of the cylinder, one of which operates the 

 steam valves, the other the exhaust valves. The rods are hook-ended 

 and work through stirrups, which when raised disengage the rods 

 from the valve camshafts. A lever is provided to work the valves by 

 hand in maneuvering. 



FIRST STANLEY STEAM AUTOMOBILE ENGINE, 1897 

 Plate 14. Fiqube 1 



U.S.N.M. no. 310524 ; original ; gift of the Mason Regulator Co. ; photograph 

 no. 9872A. 



The Mason Eegulator Co. built this engine for the first steam auto- 

 mobile constructed by F. E. and F. O. Stanley in 1897. It is a 

 2-cylinder engine with cylinders, cross-head guides, and crankshaft 

 bearings bolted to a wide flat bedplate. The valves are piston slide 

 valves with separate steam chests and are operated by individual 

 eccentrics and simple Stephenson valve gears. The bore is 2^^ inches ; 

 the stroke is 4 inches. 



The engine has the original bronze cylinders that were used on the 

 engine when it was first tested by the maker. These were removed 

 and cast-iron cylinders substituted for actual use in the automobile. 



WESTINGHOUSE JUNIOR AUTOMATIC ENGINE, c. 1900 

 Plate 14, Fiquee 2 



U.S.N.M. no. 309924; original; from the Mengel Co.; photograph no. 32583B. 



The original Westinghouse engine of tliis type was one of the 

 earliest of the modern small high-speed steam engines designed for 

 small powers and auxiliary drives. This particular engine was used 

 for about 25 years to drive a lighting generator on an Ohio River 

 steamboat. 



Some of the characteristics of this engine have been incorporated 

 in the present-day internal combustion engines of the automobile 

 type. It is a 6-by-5-inch, 2-cylinder, vertical, single-acting engine, 

 with cylinders cast in a block and a bolted-on closed crankcase. 

 A piston slide valve operates in a cylindrical steam chest cast across 

 the tops of both cylinders. The valve is driven from an eccentric 

 through a short, ball-jointed connecting rod and bell crank. The 

 eccentric is carried in the weighted lever of a flywheel governor. 



