Geneva, Nov 06, 2021
LOT 130
PATEK PHILLIPE, 18K GOLD MINUTE REPEATER HUNTING CASE WITH GUILLAUME BALANCE
CHF 15,000 - 25,000
HKD 128,000 - 212,000 / USD 16,300 - 27,100 / EUR 14,000 - 23,300
Sold: CHF 37,500
Very fine and rare, minute-repeating, 18K yellow gold, keyless, hunting cased pocket watch.
| Grading System | |
|---|---|
Grade: AAA |
Excellent |
Case: 2-8 |
Very good Slightly scratched |
Movement: 2* |
Very good Overhaul recommended, at buyer's expense |
Dial: 2-19-01 |
Very good Dent(s) HANDS Original |
Brand Patek Philippe
Year made in 1913, sold on January 27, 1919
Movement No. 174146
Case No. 401696
Caliber 19’’’, rhodium-plated, fausses cotes decoration, 27 jewels, wolf’s tooth winding, counterpoised and calibrated straight-line calibrated lever escapement, cut bimetallic compensation balance, blued steel Breguet balance spring, swanneck micrometer regulator, repeating on gongs activated by a slide on the band
Dimensions 52 mm
Signature Dial, case and movement
Notes
The Guillaume Balance. 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. Around 1900 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 temperatures, causing secondary error. In 1899, Guillaume noted that steel with an addition of 44.4% nickel had a negative square
coefficient of thermal expansion. Anibal, combined with brass in bimetallic laminae, makes expansion close to quadratic. Balances with bimetallic
rims made of anibal and brass are usually called Guillaume balances.