With the 1815 RATTRAPANTE PERPETUAL CALENDAR, A. Lange & Söhne presents three of the most sophisticated watchmaking complications in a classic design. The outstanding timepiece excels in the measurement of short and long distances: thanks to its eponymous complications, the 1815 RATTRAPANTE PERPETUAL CALENDAR indeed sets standards in both short-time measurement and the display of calendar periods.

The rattrapante function of the 1815 RATTRAPANTE PERPETUAL CALENDAR represents one of the greatest horological challenges. In addition to the conventional functions of a chronograph, this sophisticated complication is capable of measuring intermediate times and comparative times as well as determining minimum and maximum values in the course of one minute. Since the balance wheel of the manufacture calibre L101.1 beats with six semi-oscillations per second, the stopped times can be recorded with an accuracy of one sixth of a second. High-precision readings are assured thanks to the additional graduation on the peripheral minute scale.

While the rattrapante chronograph is capable of measuring different time intervals to a fraction of a second, the remarkable technical feat of the perpetual calendar lies in its “long-term memory”. As its name suggests, the complex and prescient mechanism ensures that the date, day of the week and month are correctly displayed ‒ every single day, during decades, even taking leap years into account. The calendar indications must only be corrected by one day but not until 1 March 2100; according to the rules of the Gregorian calendar, the leap year will then be skipped.

The high-precision moon-phase display has also been programmed with the long term in mind. It so closely emulates the duration of the synodic orbit of the earth’s satellite that it would take 122.6 years for the display to be corrected by one day.

The equally rare and ambitious combination of a split-seconds or rattrapante chronograph with a perpetual calendar now appears in a new guise, featuring an 18-carat white gold case with a pink-gold dial.

The new 1815 RATTRAPANTE PERPETUAL CALENDAR is limited to 100 pieces.