Important Collectors’ Wristwatches, P...

Geneva, Nov 16, 2008

LOT 34

Charles E. Jacot?s Star Duplex Escapement Chas. E. Jacot, ?Star Duplex?, No. 20376. Patented July 1852. Fine and extremely rare, 18K gold ?cabriolet? pocket watch with three-toothed duplex escapement.

CHF 8,500 - 11,000

USD 8,000 - 10,000 / EUR 5,500 - 7,000

C. Outer: three-body, detachable and reversible, the back with engraved vacant cartouche, the interior engine-turned, reeded band. Inner: four-body, ?bassine?, engine-turned, band with engraved stylized leaf decoration. Hinged gold cuvette with engine-turned border, inscribed ?John P. Buchner, 1857?. D.White enamel with radial Roman numerals, outer minute track, subsidiary seconds. Blued steel Breguet hands. M. 18???, 40 mm., frosted half-plate, 10 jewels, two in screwed gold chatons, going barrel, Jacot?s star duplex escapement with three teeth and three vertical impulse pins between, beat of 21,600 per minute, cut bimetallic compensation balance with timing adjustment screws, blued steel flat balance spring, index regulator. Movement signed. Diam. 56 mm.


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Grading System
Grade: AA

Very good
Case: 3

Good
Movement: 3*

Good

Overhaul recommended, at buyer's expense
Dial: 4-29-01

Fair

Lacking elements

HANDS Original

Notes

Star Duplex Escapement The escape wheel is in the shape of a three-pointed star with three vertical impulse pins placed on a small platform between the points of the star. The escapement beats at 21,600 per minute, an unusually high and accurate beat for the period.
Charles E. Jacot (1817-1897) Worked in La Chaux de Fonds, Le Locle, Baltimore and New York. He was a prolific inventor and innovator, especially of escapement work. At the age of 19 he visited his cousin, the son of Abraham Perrelet, in Le Locle and became involved in watchmaking. In 1837 he went to New York City, where he would remain for 20 years. Jacot invented a modification of the duplex escapement with a jumping seconds hand, known as the ?Jacot Duplex?, used extensively in watches made for the Chinese market. While in America, he registered 12 American patents for perfecting the construction of watches. An important patent, registered on July 20, 1852, was for the star duplex escapement. Charles Jacot died in August 1897.
Literature: Swiss Timepiece Makers 1775-1975, Kathleen H. Pritchard, Phoenix, 1997.