English extremely rare keyless pull wind lever Circa 1828

Extremely rare and highly unusual keyless pull wind lever watch
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An English extremely rare and highly unusual keyless pull wind lever watch, circa 1828,  gilded half plate movement, lever escapement, plain gold three-arm balance, diamond endstone, signed Willm. Cribb, Southampton Row, Russell Square, London.
Gold dial, satin finished chapter ring with Roman numerals, outer minute ring, decorative engine-turned centre and subsidiary seconds, gold moon hands.
Gold case, engine-turned case back and band, plain bow, the pendant with cap attached to fine chain for winding, with maker’s mark JB in a rectangular cameo for Josiah Barnett.
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Diameter: 49 mm
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Signed: Willm. Cribb Southampton Row Russell Square London
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The highly unusual keyless winding system incorporated into this watch was patented by Joseph Berrollas under patent number 5586 of 1827. A cap in the pendant is fixed to a chain which, when pulled outwards, winds the mainspring. The chain is similar in appearance and construction to that of a fusee chain and encircles a pulley and ratchet mechanism attached to the barrel. When the cap is released, both it and the chain are drawn back into the movement and the operation may be repeated until the mainspring is full.

Wiliam Cribb is recorded as working in Coventry and London from c. 1816, until his death in 1876.