Jones and Chambault were commissioned to design and make a movement to power the bellows of an organ clock. The clock which is a museum exhibit is wound by an attendant during guided tours.

The specifications were that it should run for ten minutes at least on one winding, be of a certain size to fit inside the clock cabinet, have stop work fitted to prevent overwinding and that the output shaft had to rotate at a certain speed without fluctuation.

I finally decided on the above design. Two huge mainspring barrels housed in a six pillared movement jointly drive the going train. A large fly vane (just visible on the back plate) governs the output speed. End stops on each arbor reduce friction to improve smoothness and extend running time. The movement is wound from the six o'clock position on the front plate by a crank handle. Large ratchet wheels mounted on the winding arbors hold the springs in the wound position. The stop work (not visible) was mounted on the base of each mainspring barrel.