HYDRAULIC MACHINERY, FOR MINES 



859 



the coaling establishment there forming for the use of the navy. The object in that 

 case is to provide power for working hydraulic cranes and hauling machines, and 

 more particularly for giving motion to machinery for putting coal into war gteamers. 

 A reservoir on the adjoining height affords an available head of upwards of 300 feet ; 

 but in order to diminish the size of the pipes, cylinders, and valves connected with 

 the hydraulic machinery, and also with a view of obtaining greater rapidity of action, 

 a hydraulic pumping engine and accumulator are interposed for the purpose of inten- 

 sifying the pressure and diminishing the volume of water acting as the medium of 

 transmission. 



Water-pressure engines erected at the Wildberg Mines, ^ in Ehenish Prussia, 

 are shown in figs. 1190 and 1191. They drain an isolated piece of ground distant 

 from the main shaft 1,800 feet. A rotary horizontal high-pressure steam-engine is 



1190 



placed in connection with steam-boilers, fig. 1 189. Two pumps, one of which is shown 

 at 6, force water into an accumulator, c. The accumulator-ram is mounted with 

 two concentric boxes, d, d, one for affording the pumping, the other the winding, 

 pressure. 



As the power required is of an intermittent character, the steam-engine is controlled 

 by the screw and weight, e, actuating the throttle-valve,/; and in order to guard 

 against the possibility of the ram rising beyond prescribed limits, a waste-valve, g, is 

 operated upon by the rod and stop, h. From the accumulator, wrought-iron pipes h', 

 fitted with cast-iron flanges, extend through an engine-shaft 60 fathoms in depth, and 

 a level 1,500 feet in length. These pipes, or main terminate in a reciprocating pole- 

 engine, fig. 1190, j, having a stroke of 5 feet ; k, k, are inlet and outlet regulating- 

 valves ; I, momentum valve, for obviating the concussion which would otherwise 

 result from suddenly arresting the flow of the water ; m, small slide valve, actuated 

 by the canti-lever, n, and ball, o. The pump-rod is attached to cross-piece, q, and the 

 pump itself is shown at s. 



To compensate for any excess of weight in the pump-rods, a balance, t, is connected 



