HYDRAULICS AND HYDROSTATICS. 



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cross tube, E F, closed at the extremities, 

 but having adjustable orifices at the opposite 

 sides, near each end of the cross tube. A 

 pipe, G, above, communicates with a supply 

 of water, which it discharges into the funnel 

 at the top of the vertical pipe, B ; and the 

 supply must be so regulated that the pipe 

 may be kept constantly filled with water 

 without running over; while the orifices in 

 the cross-pipe at E and F will deliver the 

 water with a force proportioned to the height 

 of the column in the tube, A R, and the aper- 

 tures being in opposite directions, the spout- 

 ing currents will communicate a centrifugal 

 motion to the vertical tube and its axis, C D, to which may be 

 attached a toothed wheel connected with any other machi- 

 nery. The action of this machine does not, as sometimes stat- 

 ed, depend on the resistance of the atmosphere to the jets 

 from the cross-pipe ; but is wholly owing to the hydrostatic 

 pressure of the column of water in the vertical tube, which, 

 exerting great force on the interior of the horizontal tube, and 

 that force being removed from the points whence the water 

 issues, the pressure on the corresponding points, on the 

 opposite parts of the interior of the tube, tends to make it 

 revolve, the action of both jets producing motion in the 

 same direction. Price, $5.00. 



Centrifugal Pump. (Fig. 

 263.) A machine for raising 

 water, dependent upon centri- 

 fugal force, combined with the 

 pressure of the atmosphere. 

 It consists of one, two, or more 

 arms, erect below, and branch- 

 ing out above, joined to a ver- 

 tical axle. Near the upper 

 extremity of each arm is a 

 clack valve opening upwards ; 

 while near the bottom of the 

 vertical tube, or the bottom 

 of each (if there are more than 

 one), is a similar valve, also 

 opening upwards. Water be- 

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