Scale: Unknown. A model of a pump worked by a semi-circular horizontal wheel. The model is made of wood which has been polished and the mechanism is supported by a wooden frame held together using peg joints. The semi-circular wheel houses two diagonal frames set at an angle of approximately 30 degrees which, when turned on a pivoting point, raises and lowers a horizontal beam. One end of the beam has a wide cylindrical wheel located between the diagonal frames and the lower-most frame on which it rests is faced with brass to prevent wear. The beam pivots on a post and its upward and downward motion is guided between two further posts located between the pivot post and the wheel. On either side of the pivot post are the two pump pistons, the piston rods being attached to the beam. The pistons are painted black. The model is displayed on a wooden baseboard painted black, with a bevel deck.