

PUMPING WATERS. 109 



B to start a fresh cycle. When the water level falls 

 below valve L, this valve opens, and air is admitted 

 into E for the rest of the return stroke. 



The author pointed out that if the pipe K were 

 made vertically adjustable with regard to E, the 

 point of the cycle at which L shuts could be varied, 

 and more or less air entrapped in E at will. But the 

 amount of energy stored in this air would also vary 

 with its quantity, for it is assumed that the degree 

 of compression remains constant, and fixed by the 

 pressure maintained in F. Consequently, the ratio 

 of the total energy of the working stroke to the 

 energy stored in the compressed air in E could be 

 made anything desired, or, in other words, any com- 

 pression pressure of the new charge in B could be 

 obtained, and this independent of the water lift. 

 Further, by manipulating the position of pipe K, a 

 given pump could be made to meet any conditions 

 as to height of lift, for if the lift increased K could be 

 raised so that the energy stored in the air in E re- 

 mained the same, there being less air but at a higher 

 pressure. Now, at each cycle, air is drawn into and 

 rejected from the vessel E, and if K were connected 

 to a supply of combustible mixture instead of open- 

 ing into the atmosphere, an automatic pump would 

 be provided for taking in mixture and discharging it 

 under pressure. 



Similar pumps are now being installed at the 

 Chingford Reservoir of the Metropolitan Water 

 Board, under the direction of Mr. W. B. Bryan, 

 M.I.C.E., the chief engineer. 



If the discharge were made into a reservoir from 

 which the combustion chambers A and B could be 



