VACHERON ONE MINUTE TOURBILLON
1ST PRIZE AT GENEVA OBSERVATORY
Vacheron & Constantin, Genève, No. 413628, case No. 258440.
Made in 1931.
Extremely rare and important, 18K gold, keyless pocket watch with
one minute tourbillon regulator and Guillaume balance, specially
adjusted for the 1931 Geneva Observatory Contest obtaining first
prize. Accompanied by an extract of the Geneva Observatory.
Three-body, "bassine", polished, with concealed hinge.
Glazed gold-rimmed cuvette.
White enamel with Arabic numerals, outer minute track,
subsidiary seconds. Blued steel "Breguet" hands.
42 mm. (19'''), rhodium-plated, "fausses-côtes" decoration,
19 jewels, wolf's tooth winding, one minute tourbillon regulator,
the carriage with three polished steel equidistant arms and matted
steel bridge, straight-line lever escapement, cut Guillaume anibal-
brass compensation balance with gold temperature adjustment
screws, blued steel Beguet balance spring, index regulator.