KOLLER VIEW 2/24

02 pre view. 22 The fine art of watchmaking: the perpetual calendar Preview of the Watches auction on 17 June 2024 The perpetual calendar built into wristwatches is one of the so-called ‘grand complications’: mechanical masterpieces and symbols of technical excellence and craftsmanship. Each manufacturer has developed its own system to account for the different lengths of the months and the leap day – 29 February – which occurs every four years. Watches equipped with this compli- cation and whose rate is not interrupted do not require a date correction until the year 2100, which would or- dinarily be a leap year, but will not have a 29 February. This special case, which occurs only once every 400 years, will bring the Gregorian calendar back into line with the actual course of the sun. Watches which con- tain a perpetual calendar therefore will not have to be corrected by hand for the next 76 years. The perpetual calendar movement already existed in the first half of the 18 th century. The British watchmak- er Thomas Mudge is regarded as the pioneer of this mechanism. In 1925, Patek Philippe was the first manu- facturer to offer the technically sophisticated feature of a constantly correct date display in wristwatches. The first wristwatch with a perpetual calendar and chrono- graph to be serially produced by a watch manufacturer came from the same company: the reference 1518 from Patek Philippe (ill. 5). It was launched in 1941, and only 281 watches were produced until 1954. The 1518 was a design premiere whose basic layout – calendar win- dow at 12 o ' clock, two sub-dials at 9 and 3 o ' clock and a moon phase with date at 6 o ' clock – served as a model for all its ‘descendants’. The rectangular pushers, the attractive 1950s aesthetic and the beautiful dial with tachymetre scale make this watch a prime choice for experienced collectors today. The novelty and technical mastery of the reference 1518 quickly attracted the attention of high society, in- cluding King Farouk of Egypt, the King of Jordan and Henry Graves Jr, arguably the most important watch collector of the 20 th century. Today, the rare reference 1518 is a coveted timepiece that many Patek Philippe connoisseurs consider the crown jewel of their collec- tion. Perpetual calendar wristwatches from seven different brands will be offered in our 17 June Watches auction: Patek Philippe, Audemars Piguet, Breguet, Urban Jür- gensen, IWC, Ulysse Nardin and Jaeger LeCoultre. 1 Audemars Piguet. Royal Oak, perpetual calendar, 18K yellow gold. Estimate: CHF 60 000/120 000 2 F. P. Journe. Tourbillon Souverain, rose gold, 2006. Estimate: CHF 140 000/280 000 3 A. Lange & Söhne. Tourbillon, platinum 950, circa 2000. Estimate: CHF 70 000/140 000 For further information Wristwatches & Pocketwatches Uwe Vischer vischer@kollerauctions.com Online catalogues www.kollerauctions.com 4 Patek Philippe. Chronograph with perpetual calendar, platinum 950. Circa 1998. Estimate: CHF 80 000/160 000 5 Patek Philippe. Chronograph with perpetual calendar, ref. 1518. 18K yellow gold. 1950. Estimate: CHF 180 000/360 000 1 2 3 4