11,500 CHF
French, circa 1770. Important and extremely rare watch with Sully frictional rest escapement, constructed on the principle of the watch elaborated in 1715 by Julien Le Roy and Henry Sully, constructed by Julien Le Roy and presented by Sully to the Académie des Sciences on June 10, 1716. Silver gilt Louis XV with glazed back. Slightly later white enamel with radial Arabic numerals and outer minute ring. Later blued steel hands. Notes To understand the purpose of such unusual arrangement for a watch movement, it is important to read in either the second or the third edition of Sully's Règle Artificielle du Temps, his Description d'une montre d'une nouvelle invention, written in 1716, where the calibre is illustrated Fig. 15, and his Histoire critique de différentes sortes d'échappement, probably written between 1726 and 1728, and included by Julien Le Roy in the third edition of Règle Artificielle du Temps, posthumously publihed in 1737. Sully discusses the variation in timekeeping of an ordinary verge watch, according to whether it is hanging or lying. He mentions several causes, such as lack of balance poise and the differing amplitude of the balance depending upon whether the verge pivots are running on their sides or on their ends.For more information, please refer to the article by Charles Allix, Sully, Verlinden and others...., Antiquarian Horology, Winter 1980. (A copy of the article will be supplied to the buyer.)This watch embodies, the features of Description
Auctioneer:
Antiquorum
Date:
1999-10-23
