HYDRAULIC MACHINERY, FOR MINES 



865 



The communication between the faces of the two plungers is entirely free ; and 

 hence, if the acting-ram, a, be raised, the balance-plunger, e, will fall and counter- 

 balance the rods to the extent of its weight, less the trifling amount of friction incident 

 to the movement. 



The details of this counterpoise arrangement (jig. 1199) are, in most respects, 

 identical with those already described ; but this Jiff., which represents the pump-rod 

 iii an inclined position, exemplifies the facility of changing the direction of the power. 

 a, plunger attached to main-rod ; b, pipe connecting the balance ram-case ; e, balance- 

 ram ; /, balance -box ; gg, guides for balance-box : h, pipe for supplying water to 

 the ram-cases when leakage occurs. 



1199 



In fig. 1200 (figs. 1 to 7) the arrangement employed at the Von der Heydt Colliery, 

 Prussia, is shown. Fig. 1 side elevation: c guides for vertical plunger, D plunger-case, 

 K inclined plunger-case, H pump rod, M hydraulic main, N sole of level, o valve-boxes. 

 Fig. 2 transverse elevation : A plunger-case, D bearers supporting case, w hydraulic 

 main, o valve-box. Fig. 3 plan : B plunger-case, D bearers for inclined plungers, J 

 forming part of the hydraulic main, N bottom of level, o valve-boxes. Fig. 4 longi- 

 tudinal section of valve-box: o.s. inlet, n pipe, P ordinary mitre valve for supplying 

 main with water when necessary, ; entrance to hydraulic main, G valve for discharging 

 water from main,Y valve-stud, i spring. Fig. 5 transverse section of valve-box : S.R. 

 inlet ; P valve seating, T entrance to the main, G ejection valve, Y stud, i spring, wadjust- 

 ing nuts for giving greater or less tension to the spring. Fig. 6 section of plunger and 

 bucket pump : A bucket rod passing through plunger, Y plunger, z bucket. Fig. 7 eleva- 

 tion of plunger pump valve-boxes and rising main : Y plunger-case, B stuffing box, c 

 water, main, D valve-box, H pump-rod. The motive plunger in this case is ~D,fig. 1. 

 This plunger by means of the water contained within the main forces the plunger B 



VOL. II. 3 K 



