OF HYDRAULIC ENGINES. 



133 



LECT 

 V. 



The forcing-pump raises water through the box H i 

 the same manner as the sucking pump does, when the in S-P vln P- 

 plunger or piston g is lifted up by the rod D d. But 

 this plunger has no hole through it, to let the water in 

 the barrel B C get above it, when it is depressed to B, 

 and the valve b (which rose by the ascent of the water 

 through the box H when the plunger g was drawn up) 

 falls down aud stops the hole in JJ, the moment that the 



