CATALOG OF THE MECHANICAL COI-LECTIONS 

 MISCELLANEOUS STEAM INJECTORS 



133 



The following patent models of injectors, transferred from the 

 United States Patent Office, are not otherwise described or illustrated. 

 The list is chronological. 



Cataloged photographs of injectors in the collection are as follows : 



U.S.N.IM. nos. 309522A and E. Two photographs and one card of the original 

 Giffard injector. From the Conservatoire des Arts et Metiers. 



U.S.N.M. no. 309525. A colored phantom photograph of a modern Sellers 

 injector showing the construction and operation. From Gatchel & Manning, Inc. 



STEAM PUMPS 



WORTHINGTON DIRECT-ACTING STEAM PUMP, 1855 



Plate 28, Figure 1 



U.S.N.M. no. 309245 ; original patent model ; transferred from the United States 

 Patent Office ; photograph no. 32644D. 



This model was submitted with the application for the patent 

 issued to Henry R. Worthington, July 31, 1855, no. 13370. 



The model represents a double-acting water cylinder of a direct- 

 connected steam pump so designed that toward the end of each stroke 

 the pressure on each side of the water piston will be momentarily 

 balanced to permit the expansion of steam already in the steam cyl- 

 inder to quickly move the piston so that the steam valve operated by 

 the piston will be quickly and positively opened for the return stroke. 



At the midpoint of the water cylinder is an opening connected to 

 the force pipe through which the water is discharged. The piston 

 is made of such length that this opening is uncovered to the suction 

 side of the piston only near the end of the stroke. The effect of this 

 is momentarily to subject both sides of the piston to the same water 

 pressure and so relieve the steam piston of most of its resistance so 

 that it can move rapidly and actuate the valve sharply and positively. 



