Rare and very early Prest Patent keyless movement, circa 1820.
The smaller size fullplate going-barrel movement of typical early style, the barrel-bridge with engraved scale and the distinctive screw held steel bearing on the top plate supporting one end of the main contrate form of winding wheel which is mounted under the dial. Single-roller detached lever escapement, almost certainly a conversion from the original cylinder. Gold balance, spiral balance-spring, the index of these smaller sized watches never being fitted with John Roger's distinctive compensation-curb - it is not lacking. Signed enamel dial, gold hands. 39 mm diameter, 10 mm deep, not including dial and centre arbor.
John Roger Arnold, the famous son of a famous father and a very good watch and chronometer maker in his own right, the Arnold firms foreman being Thomas Prest in whose name PATENT 4501 was taken out in October 1820. This was the first commercially successful keyless work, pre-dating Patek, and was used by the Arnold firm, later taken over by Charles Frodsham, for around forty years - see also the Camerer Cuss Book of Antique Watches, page 230 for a later example.
NB: Previously sold by me in the year 2000 in my Postal Auction Catalogue No 2, item 16, Hans Staeger, in his impressive book on Arnold, records this as the earliest known example of this series. He missed the fact, however, that No 3 was sold at Christies in 1975. See also Antiquarian Horology, September 1974, where the then owner, Ken Shanks, discusses No 11 and the website of Tom McIntyre who was a later owner. I also have a good example of a later three-quarter plate Prest keyless movement by J R Arnold, No 6394, for sale on my website.
Dial with hair cracks and a later but sensible conversion of the escapement, otherwise complete and nothing appears to be broken. It is, however, unwilling to run but is a very rare chance to own such an early example. Sold as needing at least a service and fresh oil to work correctly.
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