$40,120
“First Prize” Patek, Philippe & Cie. , Genève, “Chronometer – First Prize - Observatoire de Genève”, No. 811285, case No. 289539. Made circa 1930, submitted for Observatoire de Genève testing in 1934. Very fine and rare, keyless, silver deck chronometer with Guillaume balance. Accompanied by an Extract from the Observatoire de Genève register attesting to its outstanding performance, and an Extract from the Archives. Four-body, "demi-bassine", solid, polished, hinged silver cuvette. Matte silver with painted Arabic numerals, outer minute track, subsidiary seconds dial. Blued steel "spade" hands. Notes A very fine example of a Patek Philippe deck watch from a small series of about 35, all destined for Obervatory trials. Almost all were cased in silver; one example exists in gold. Anibal (Acier au nickel pour balanciers),an alloy invented by Dr. Charles Edouard Guillaume, exhibits unusual properties, both in terms of thermal expansion and in changes in elasticity. These properties are very different from those of two other famous alloys invented by Guillaume, Invar and Elinvar. At the end of the 1800's, Guillaume attempted to eliminate the so-called Middle Temperature Error caused by the fact that the change of rate in a timekeeper with a steel-brass bimetallic balance is approximately a linear function of temperature, while the change of rate caused by change in elasticity of a balance spring is approximately a quadratic function. Thus, it equals zero at only two tem
Auctioneer:
Antiquorum
Date:
2007-03-28
