Nicely finished pocket chronometer movement by this most interesting maker, circa 1815.
20-size fullplate fusee movement jewelled to the 3rd, with cap jewels on balance (diamond) and escape. Earnshaw spring-detent escapement with jewelled impulse and unlocking rollers, the detent of dovetail form, as introduced by Robert Pennington, as is the compensation balance which is drilled and tapped for screws. Rare gold 6-turn helical balance spring with terminal curves. One piece enamel dial numbered 2021, gold hands. 48 mm diameter, 15.5 mm deep, not including centre arbor.
James Hatton, son of Thomas Hatton. In partnership with George Margetts till around 1805, then working on his own till around 1816, after which he formed a partnership with Clement Harris. Hatton's numbering system is not fully understood, at least not be me. He initially carried on the Margetts & Hatton 4-digit series but appears to have started his own 3-digit series around 1812. None, though, are known to be as high as 798, let alone 2021, though it is clear that the dial was made for the present brass-edge which is also clearly made for this watch. It may be, however, that the number/s reflects the actual maker of this movement. If so, it is likely to be Robert Pennington.
The dial with hair cracks, a later minute hand, and lacking the seconds hand, the detent buckled and straightened at some point - this looks as though it could certainly be improved. Not cleaned by me but ticks with a good action when wound.
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