CATALOG OF THE MECHANICAL COLLECTIONS I35 



vessel when steam is down and the steam pump cannot be used, 

 while eliminating some of the piping that would be necessary if 

 separate pumps were provided. 



KING DIRECT-ACTING PUMP VALVE GEAR, 1870 



U.S.N.M. no. 308682 ; original patent model ; transferred from the United States 

 Patent OflSce ; not illustrated. 



This model was submitted with the application for the patent 

 issued to John C. King, of New York, N. Y., September 20, 1870, 

 no. 107504. 



The model represents a direct-connected steam pump provided 

 with rotary oscillating valves on the steam and water cylinders 

 operated by an arm on the piston rod and a swinging lever. The 

 peculiar feature of the design is the use of a sharp-edged spring- 

 actuated slide, which acts upon a roller on the swinging lever to 

 rapidly change the valve position as the pistons near the end of 

 their strokes. During the first part of the stroke the roller on the 

 swinging lever acts upon one side of the slide and forces it up against 

 a coil spring. Toward the end of the stroke the roller passes under 

 the sharp edge of the slide and the force of the spring causes the 

 slide to push the roller and swinging lever rapidly in the direction 

 in which it is traveling. 



WORTHINGTON DUPLEX STEAM PUMP, 1871 



U.S.N.M. no. 308681; original patent model; transferred from the United States 

 Patent OflBce ; not illustrated. 



This model was submitted with the application for the patent issued 

 to Henry E. Worthington, of New York, N. Y., June 20, 1871, no. 

 116131. 



The model is a relief panel showing a section through the two steam 

 cylinders of a duplex pump arranged to use steam at boiler pressure 

 in one steam cylinder of small diameter, expand the exhaust steam in 

 a receiver of much larger volume than the small cylinder, and use the 

 steam at low pressure in a second cylinder of larger diameter. This 

 arrangement was devised to permit the use of steam expansively in 

 a duplex pump without the use of two compound cylinders, as was 

 formerly the method. 



CAMERON PUMP VALVES, 1874 

 Plate 28, Figuhk 2 



U.S.N.M. no. 30S6S6 ; original patent model ; transferred from the United States 

 Patent Office; photograph no. 32644B. 



This model was submitted with the application for the patent issued 

 to Adam S. Cameron, of New York, N. Y., November 10, 1874. no. 

 156769. 



