Accompanied by Patek Philippe Extract from the Archives confirming production of the present double dial watch with secular perpetual calendar in 1972 and its subsequent sale on 16 November 1972 and wooden presentation box.
This watch is one of only two references 871 watches made in 1972 by the master watchmakers of Patek Philippe in Geneva incorporating a secular perpetual calendar. It is, for esthetical reasons, fitted with two dials: the front for the time indication, the back displaying on three subsidiary dials the week day, date, month and leap year cycle. The aperture shows, in two separate windows, the year. This technical marvel was the first time Patek Philippe incorporated a secular perpetual calendar into one of their creations and was only used once more for the famous Calibre 89 - the ultra-complicated multi-million dollar Grande Complication watch designed to mark the firm's 150th anniversary.
The present watch was made for Seth G. Atwood, the second example of this model for the Stern family, owners of Patek Philippe, is now permanently on exhibit at the prestigious Patek Philippe Museum in Geneva. Never been offered at auction before, it is doubtlessly one of the rarest opportunities for the connoisseur to acquire one of Patek Philippe's most important, elegant and exclusive creations of the 20th century.
Perpetually yours - the secular or "true" perpetual calendar
Watches with date indication are much appreciated for their practical use, but remind ourselves constantly that our calendar, more precisely the Gregorian calendar, is of a rather complex nature. The dividing of a calendar year into 12 months with either 28, 29, 30 or 31 days did never render it any easier to watchmakers to design a mechanical device displaying, nota bene mechanically, the correct date. It is therefore by no surprise that the vast majority of mechanical watches ever produced require a manual adjustment at the end of all months which have less than 31 days.
Watches fitted with a perpetual calendar mechanism are the most sophisticated solution to this problem. A true challenge to any master watchmaker to design and build such a calendar, perpetual calendar watches are fitted with an ingenious mechanism programmed to automatically and correctly, according to the current month, advance the date hand to the first day of the next month - no difference whether the actual month has 30 or 31 days. Furthermore and more impressively, a "quantième perpétuel" (the French designation for perpetual calendar) takes the leap year rule into consideration, resulting in an astonishing performance of the date hand at the end of February: For three consecutive years the date indication moves straight from February 28 to March 1, however during a leap year it will only move to the first of March after having shown February 29.
The Gregorian calendar reform introduced leap years as a necessity to compensate for the approximately 6 hours which an average solar year measures more than 365 days. In fact, during four years this difference adds up to an entire day - resulting in leap years accounting for 366 days. It is however little known that this elegant solution is not completely compensating for the discrepancy between a solar and calendar year - precisely speaking of 5 hours, 48 minutes and 45 seconds. In order to "perpetually" match the calendar with the solar year it was imposed that leap year divisible by 100 shall not be leap years - but furthermore if such years are divisible by 400 they shall again be. Consequently, the years 1700, 1800, 1900, 2100, 2200 and 2300 are not leap years, but 1600, 2000 and 2400 are. This poses the ultimate challenge for watchmakers to construct a truly perpetual calendar - also known as the secular calendar - to always correctly display the date according to this rule. Few have ever dared to approach such a stupendous project - fewer have ever succeeded.