PATEK PHILIPPE & CO., GENÈVE [百達翡麗，日內瓦] | AN EXTREMELY FINE AND RARE PINK GOLD OPEN-FACED KEYLESS LEVER WORLD TIME WATCH WITH CLOISONNÉ ENAMEL MAP OF NORTH AMERICA 1948, REF. 605 HU, MOVEMENT NO. 930.864, CASE NO. 654.949 [605HU型號極罕有粉紅金世界時間懷錶飾掐絲琺瑯彩繪北美洲地圖，1948年製，機芯編號930.864，錶殼編號654.949]

The Heures Universelles watches are among the most coveted of all Patek Philippe’s vintage production, and examples form the centrepiece of some of the world’s most important watch collections. Reference 605 was one of the earliest models to incorporate the ingenious world time system developed by the famed watchmaker Louis Cottier; production began in 1937 and continued for approximately thirty years, during which time less than one hundred examples were made. Research suggests that three-quarters of the Ref. 605 watches made were delivered in yellow gold cases, with just one quarter in pink gold. The model was initially produced with plain metal satin finished centres in tones of champagne, pink or silver. However, from the late 1940s, Patek Philippe began to commission a small series of richly coloured cloisonné enamel dials. The cloisonné dials destined for the world time models predominantly featured ‘maps.’ These ‘maps’ were stylised views of the continents and versions included renditions of the Americas, either the North alone or North and South together, as well as larger world views such as Europe shown together with Africa and Asia or even an entire world view. Cloisonné enamel dials have long been favoured by collectors for their distinctive designs and vibrant colours which, with their indelible finish, remain undimmed by the passing years. The allure of the cloisonné dial is further heightened by the fact that each is unique – being hand painted, subtle variations are inevitably made both in tonal colouration as well as by the inclusion and placement of details and motifs.

The Heures Universelles function in Ref. 605 is operated via the bezel, a mechanism shared by this and the wristwatch Ref. 1415. To set the watch up, the user simply rotates the bezel so that their current location is displayed at the twelve o’clock position, and they then advance the hands to the correct local time. The recessed 24-hour ring is geared to turn automatically as time advances, and will therefore indicate the correct time in all zones around the world. Since the case, dial and movement are all integral to the technical function of the watch, Louis Cottier supervised the production of each element. It is interesting to note that the present example, like many of Cottier's inventions, lists London and Paris on the same time zone, Greenwich Mean Time. On 15 June 1940, Paris converted to Central European time due to the war. For many years it was thought that Paris would eventually revert back to GMT, and there are Patek Philippe Heures Universelles watches and wristwatches from as late as the 1970s which still list Paris and London on the same time zone.

Louis Cottier (1894-1966) was born in Carouge and attended the Horological School of Geneva before going to work for his father and horological mentor Emmanuel Cottier (1858-1930). Like his father, Louis was a talented mechanical genius and went on to develop numerous patents that changed the face of watchmaking. Reacting to the realities of the Great Depression, Cottier saw a niche in high-end watchmaking and focused his talents on the development of complicated watches for Patek Philippe, Agassiz, Rolex, and Vacheron Constantin. Foremost among these discoveries was his development of the world time mechanism in the 1930s. This invention would inspire some of the most iconic Patek Philippe complications.