English chronometer with spring detent escapement Circa 1822

Heavy silver pocket watch by Parkinson & Frodsham
–
A heavy English pocket chronometer with spring detent escapement and resilient stud, circa 1822. This device was probably intended to let the hairspring breathe more evenly in the style of the Breguet overcoil.
Tiered polished silver case with London Hallmarks from 1822 and case maker’s punch mark CL (Charles Lupton, 6 St. James’s Place, Clerkenwell). Signed enamel dial with Roman radial hours, outer minutes track with Arabic five minutes numerals, subsidiary dial for the seconds, and gold spade hands. Unusual and rare spring detent chronometer movement with so-called resilient stud, chronometer balance with two trapezoidal weights, diamond endstone, signed and numbered plate. The mechanism resilient stud should serve to let the hairspring ‘breathe’ more evenly, comparable to a Breguet hairspring.

–
Diameter: 59 mm
–
Weight: 191 g
–
Signed: Parkinson & Frodsham, London
–
Parkinson & Frodsham,
In 1801 William James Frodsham, son of William Frodsham the Younger and William Parkinson, founded the company to become famous as Parkinson & Frodsham at 4 Change Alley, Cornhill, in London. The two partners decided to specialize in pocket- and marine chronometers; their business location was perfect because the coffee houses in the vicinity, such as Garroway’s, were frequented by captains, merchants and sales representatives of foreign trading houses who came to make their transactions. Very soon, the company did not only supply the British Admiralty with their goods but exported them to the whole of Northern Europe.