This pump can still be found on farms everywhere.
Water enters the lower chamber when the movable sealed plate is raised.
The red valve is open and the green valve on the plate is closed. When the plate is pushed back down, the red valve closes, and the liquid in the lower chamber is forced through the green valve, which opens. On the next upstroke of the plate, the liquid which passed through the green valve on the previous downstroke is raised and spills out the spout.