Movement No. 78 is a variation of Movement No. 77. The oscillation of a lever about a fixed fulcrum drives a ratchet wheel through two pawls acting alternately, producing a nearly continuous rotary motion. The dual-pawl arrangement ensures that as one pawl pushes the ratchet wheel forward, the other engages to prevent backward slip, resulting in smoother and more consistent rotation compared to a single-pawl design. This mechanism is commonly found in hand tools, hoisting equipment, and early clockwork devices.
78. A modification of 77.