[1028]. Water wheel and pump.
[1029]. Single-acting bucket or suction pump.
[1030]. Single-acting ram force pump. Sometimes an open top cylinder and piston are used instead of a ram, as [No. 1029].
[1031]. Double-acting ram and piston pump. Forces on both strokes; sucks only on the up stroke.
[1032]. Double-acting plunger or ram pump, externally packed; a favourite arrangement.
[1033]. Double-acting piston pump, four valves. This is of course a type of a very great variety of pumps.
[1034]. Double-action piston pump, without valves. The piston has an oscillating or radial motion (see plan), as well as an up and down motion, so that the two ports are alternately open to the upper and under side of piston by the small passages A A. The required motion can be obtained from [No. 406], crank motion.
[1035]. Rope pump. A simple endless soft or porous rope absorbs water at its lower part (immersed), which water is pressed out of it between the rollers at top.
[1036]. Apparatus to supply air to air vessels. The main pump at every stroke draws a small quantity of water from the small air vessel A, and on the return stroke forces an equal quantity of air from the smaller to the larger vessel B. C is a double air valve.
[1037]. Combined bucket and plunger pump draws on the up stroke only, but delivers on both strokes.