Watch in brass by Simon Hackett (member Clockmakers’ Company, 1632, and Master 1646, d. 1664); London, England, c. 1660; dia. 1½” (3.81 cm.).
This watch has certain modern features: the circular movement, the hinge shape (cf. Barnes and Bull watches) and though the balance cock is of the old type, fastened by a pin, the setting up of the spring is more sophisticated, having a worm gear with an indicator disc to show how far the worm has been moved. The edge of the plate bears a little engraving.
The alarm is fitted with stopwork (a pinion gearing with a segment of a toothed wheel) to prevent the spring being overwound. The pierced case contains the bell with the movement inside it.