Model of an Oscillating Pump

Model of a crank pump on a tripod. It is a double-acting pump with two square pump cylinders, connected at the bottom by a single round pump pipe. The pump plungers consist of a metal plate placed diagonally in the pump cylinder, upon which two triangular valves covered with leather are mounted; they are weighted with lead. At the bottom of the square pump cylinders, pump buckets of the same design are placed. The plungers are connected to each other by a chain running over a wheel in the pump tank; on the outside, a crank is attached to the axle of the wheel, and above it a yoke for a chain or rope; with this yoke, the crank motion is set in motion, causing the plungers to be pulled up and lowered in turn.