What is (a) The solid piston of a force pump; the instrument by which water is forced in a pump. (b) A small hand pump for sinking pits, draining cellars, etc called?

forcer — (Mech.) (a) The solid piston of a force pump; the instrument by which water is forced in a pump. (b) A small hand pump for sinking pits, draining cellars, etc. (Webster's 1913.)

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