The device demonstrates the operation of the perpetual screw; it is a simple machine.

The perpetual screw (made of iron) is fixed to a pulley and a crank, so that when the crank is turned the screw rotates continually, together with the toothed wheel (not original) which meshes with the screw and on whose axis a wooden sprocket (not original) is mounted. Turning the crank raises both the small and large weights attached to the sprocket, the latter much more slowly; the advantageous ratio of the weights raised, however, involves an increase in the number of revolutions performed by the wheel.
The instrument was acquired in 1801.

Device on display.