Important collector's watches, wristw...

Hotel Richemond, Geneva, Apr 13, 2002

LOT 28

Giovanni Francesco Gioly (Jean François Joly), Roma, dated 1693. Extremely rare and very fine small ebonized quarter-repeating bracket clock with early balance and straight balance spring.

CHF 100,000 - 120,000

USD 60,000 - 70,000

Sold: CHF 179,500

C. Molded base on bun feet, tapered top, hinged front and back doors. D. gilt brass ring with champlevé radial Roman numerals, inner quarter-hour divisions, outer minute divisions with five-minute Arabic figures set on dark blue velvet, each corner with pierced and engraved appliqué decorated with stylized foliage and finished with fleur de lis. Gilt pierced hands. M. Rectangular, 64 x 74 mm, gilt brass, baluster pillars, fusee and cat-gut, verge escapement, four-arm steel balance with straight hog?s bristle balance spring, whose length is regulated by micrometric screw regulator set on two-footed large (56 mm ø) solid cock decorated with engraved flowers, pull repeat, repeating hours on the bell mounted on the top of the movement and quarters on the one mounted below the movement. Signed on the movement. Dim. Height 29 cm, base width 17 cm.


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Grading System
Grade:
Case: 3

Good
Movement: 3*

Good

Overhaul recommended, at buyer's expense
Dial: 3-01

Good

HANDS Original

Notes

The idea of applying a spring to a balance is due to Dr. Robert Hooke, who around 1660 wrote his famous ?Ut tension sic vis? (tension is equal to force), which became the basis of the future theory of elasticity. Also in 1660, he applied a spring to a balance. As described by his friend Durham it was a ?tender straight spring, one end whereof played backward and forward with the balance?. Fifteen years later Huygens invented a spiral balance spring much superior to Hooke?s. In 1674 Jean d?Hautefeuille opposed Huygen?s application for a patent with the Academy of Sciences, claiming that he used it before. According to Berthoud, Hautefeuille?s spring was ?a straight spring fastened to the top plate and the free end acting freely on the periphery of the balance?. Hautefeuille, however could not present a watch as proof. It is said that Hooke had some watches made with his straight spring but none have survived. We know of only two clocks with a straight balance spring, this one being one of them.