346

Steam Fire-Engine.

[Book III.

“ A the double acting force pump, cast of gun metal, firmly secured to thecarriage frame by four strong brackets cast on its sides. a, a, Suctionvalves. a !, a', Suction passages leading to the cylinder. a", Chambercontaining the suction valves, and to which chamber are connected suctionpipes a!", a ! ", to which the hose is attached by screws in the usual man-ner, and closed by the ordinary screw cap. The delivering valves andpassages at the top of the cylinder are similar to those just mentioned.

I

B the air vessel, of a globular form, made of copper. b b deliverypipes, to which the pressure hose is attached : when only one jet is re-quired, the opposite pipe may be closed by a screw cap, as usual. Thepiston or bücket of the force pump to be provided with double leatherpackirig: [cupped leathers] the piston rod to be made of copper.