This picture shows the original Smiths Balance.
Regulation requires full access to the balance and is achieved by moving the pointer situated above the balance wheel.
Clumsy fingers might damage the hairspring so a guard, shown in the picture below, was sometimes fitted.
This picture shows the guard placed above the balance wheel. The guard also shows the direction to move the pointer for slower or faster. In use, the wheel is held steady and the pointer moved very slightly.
This shows a later version of the floating balance which is now fitted with an improved method of regulation by means of the screw visible top left which projects through the rear cover and can be adjusted with a screwdriver or coin using the graduated dial marked on the cover.
Rear view of later version floating balance clock. Note the graduated scale to help accurately regulate the clock and also the clear description of the movement.
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