Exceptional horologic works of art

Hotel Noga Hilton, Geneva, Oct 11, 2003

LOT 240

French, Bongrand System, circa 1820. Fine and very unusual silver and gold manual perpetual calendar with equation of time and Réaumur thermometer.

C. Three-body, ?Empire? by François-Jean Veyrat, engine-turned back, reeded band, double fluted gold bezels, pendant with double knurled button for setting the date. D. Matte and silvered, outer annual calendar ring with blued steel Breguet hands, inner equation sector having blued steel hand with gold sun at the tip, at 6 o'clock small Réaumur thermometer scale. M. 60 mm, gilt brass, skeletonized, center with the annular wheel driven by a worm gear controlled by the button in the pendant, fixed to this wheel, a blued steel skeletonized equation cam which moves a spring-loaded rack meshing with equation wheel, set loosely in a center post.Case punched with casemaker's mark and French guarantee marks.Diam. 65 mm.