87. A contrivance for a self-reversing motion. The bevel-gear between the gears, B and C, is the driver. The gears, B and C, run loose upon the shaft, consequently motion is only communicated when one or other of them is engaged with the clutch-box, D, which slides on a feather on the shaft and is shown in gear with C. The wheel, E, at the right, is driven by bevel-gearing from the shaft on which the gears, B, C, and clutch are placed, and is about to strike the bell-crank, G, and produce such a movement thereof as will cause the connecting-rod to carry the weighted lever, F, beyond a perpendicular position, when the said lever will fall over suddenly to the left, and carry the clutch into gear with B, thereby reversing the motion of the shaft, until the stud in the wheel, E, coming round in the contrary direction, brings the weighted lever back past the perpendicular position, and thereby again causes it to reverse the motion.