Important Collectors’ Wristwatches Po...

Geneva, Hotel Des Bergues, Oct 21, 1995

LOT 87

Brockbank, London, No. 3791, with London hallmarks for 1825. Fine and rare 18 ct. gold pocket chronometer with special escapement.

CHF 11,000 - 13,000

C.Three body, Empire, engine-turned with fixed bezel, marked "VN.W." (William Wright). Small monogram on the back and name of the owner engraved on the cuvette. D. Egg-shell enamel with Roman nummerals and subsidiary seconds. Blued steel Breguet hands. M. Hinged e t brass full plate with cylindrical pillars, fusee with chant and maintaining power, Petto crossdetent escapement, three-arm compensation balance with trapezoidal weights and timing screws, free spmng blued steel flat balance spring, gilt brass cock engraved with foliage and symbols, diamond endstone. Signed on the back plate. In very good condition. Diam. 51 mm.


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Notes

Note: James Petto was active from about 1780 to 1800 and worked for the Brockbanks. He is remembered by his cross-detent variant of the spring detent escapement which he may have arrives at to combine the theoretical advantage of Arnold's and Eamshaw's lay-out, but also possibly to evade Eamshaw's patent. Several pocket chronometers were made by Brockbanks and long aftér the British makers had given up, Breguet thought sô well of it as to introduce it into at least two of lis fnnest tourbillons made after 1810.