It will be seen the impulse roller is staked flat against the hub E of the balance staff.
There are many points worthy of consideration in the making of a balance staff that are too often neglected.
We have already discussed how to locate and plant the center of the balance staff.
The small circle at A represents the center of the pallet staff, and the one at B the center of the balance staff.
There is no jeweling in the escapement or on the other end of the balance staff.
Our advice is to set both stones in places corresponding to the axis of the balance staff, and the escape-wheel mobiles.
In these frictional escapements the balance staff locked the train while the balance performed its arc of vibration.
Five jewels are found in most instances, two cap jewels and two hole jewels for the balance staff and a jeweled impulse pin.
Potance or PotenceA vertical or hang down bracket, supporting the lower end of the balance staff in full-plate watches.
There are five jewels, four to support the balance staff and an impulse jewel.