Important Collectors’ Wristwatches, P...

Geneva, Mandarin Oriental Hotel Du Rhône, Nov 12, 2006

LOT 344

Patek Philippe & Cie, Genève, No. 170417, case No. 274698. Made in 1912, obtained the Geneva Observatory rating certificate on June 11, 1913, and sold on December 8, 1917. Very fine silver deck and pocket ?EXTRA? adjusted lever chronometer with 36-hour power reserve indicator and Guillaume balance. Accompanied by the Extract from the Archives.

CHF 25,000 - 30,000

EUR 16,000 - 20,000 / USD 20,000 - 24,000

C. Four-body, ?bassine?, polished, silver hinged cuvette. D. Heavy, solid silver, bold champlevé radial Roman numerals, outer champlevé minute track, up-and-down sector at 12, and subsidiary seconds. Blued-steel ?spade? hands. M. 21?', 21 jewels, straight line calibrated lever escapement, anibal-brass Guillaume balance with ?winged? arms, gold temperature adjustment screws and platinum mean time ones, special alloy Breguet balance spring with Phillips' inner and outer terminal curves, diamond endstone, ?swan-neck? micrometric regulator, Patek Philippe & Cie. keyless winding (Swiss patent 2680, 27 September 1890), differential up-and-down mechanism. Dial, case and movement signed. Diam. 60 mm.


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Grading System
Grade: AAA

Excellent
Case: 3

Good
Movement: 3*

Good

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

Good

HANDS Original

Notes

Guillaume Balance In 1899, Dr. Charles Edouard Guillaume noted that steel with an addition of 44.4% nickel had a negative square coefficient of thermal expansion. This alloy, combined with brass in bimetallic lamina, makes its expansion almost quadratic. Balances with bimetallic rims made of anibal (an alloy invented by Guillaume: Acier au NIckel pour BaLanciers) and brass are usually called Guillaume balances, or, as their inventor called them, integral balances. When combined with special balance springs, they exhibit remarkable temperature stability, on occasion not exceeding 1/50 second per day at 1oC. The present watches are exceptionally well-made and adjusted for the Observatory Contests. Every detail, such as the special Guillaume balance with small ?wings? at the arm for poising ?in the raw?, before the screws are put in, which assures that temperature compensation adjustment will not affect poising, the superior polish of the steel parts, the olive jewel holes, and the very light undercut escape wheel with raised teeth, shows that these watches were very special ones.