311. Double three-legged gravity escapement. Two locking-wheels, A, B, C, and a, b, c, are here used with one set of lifting-pins between them. The two wheels are set wide enough apart to allow the pallets to lie between them. The teeth of the first-mentioned locking-wheel are stopped by a stop-tooth, D, on one pallet, and those of the other one by a stop-tooth, E, on the other pallet.