A pendulum is driven by the scape-wheel A, and pallets B B in the usual way.
The centre wheel drives the “second wheel” D by its pinion d, and that again drives the scape-wheel E by its pinion e.
This escapement is chiefly designed for turret clocks with heavy dial-work requiring much power on the scape-wheel.
It will be observed that the teeth of the scape-wheel have their points set the opposite way Dead escapements.
In clocks with only three wheels in the train it is best to make the scape-wheel turn in two minutes.
The arbors of the scape-wheel and hour-wheel are distinct, their pivots meeting in a bush fixed somewhere between the wheels.
With a common anchor escapement the scape-wheel can be driven round by wagging the anchor to and fro.
Accordingly, attempts have frequently been made to drive the scape-wheel by a spiral spring, like the mainspring of a watch.