Anchor escapement clockmaker George Graham around 1715. This gradually superseded the recoil escapement and is used in virtually all modern pendulum clocks with anchor escapements. The anchor escapement consists of two parts: the "escape wheel", which is a vertical wheel with pointed teeth on it rather like saw teeth, and the "anchor", shaped vaguely like a ship's anchor, which swings back and forth on a pivot just above the escape wheel. On the two arms of the anchor are curved and flat faces which the teeth of the escape wheel push against, called "pallets". The central shaft of the anchor is attached
Grasshopper escapement in the stable block at Brocklesby Park in Lincolnshire. This proved to be unreliable, needing repeated attention by which Harrison was inconvenienced, so around 1722 he modified the escapement by putting a hinge in the middle of each arm of the anchor. The hinged pallets both pointed the same way, opposing the rotation of the escape wheel. As the escape wheel pushes the pallet, the hinge moves away from the escape wheel. The pallet pivots about its contact point with the wheel as it pushes the anchor. At the same time, the other pallet is approaching the wheel. When it