SIHH 2013 is in full swing and A. Lange & Sohne is not pulling any punches. ALS has announced the new 1815 Rattrapante Perpetual Calendar, and it looks to be a complete knockout. Featuring a new Lange calibre, the L.101.1, the 1815 Rattrapante Perpetual Calendar combines some of the most sought after complications into one dazzling package that has been designed as a tribute to early A. Lange & Sohne pocket watches.

The L.101.1 movement, which consists of 636 separate parts,  incorporates a rattrapante or split-seconds chronograph, a perpetual calendar, moon phase indicator and power reserve display. The L.101.1 is ALS’s eighth in-house chronograph movement and sports dual column wheels, 43 jewels and a power reserve of 42 hours. As is the case with perpetual calendars, this ALS will accurately measure the date to 2100, at which point a one-day correction will need to be applied. Thanks to the unique way in which the Gregorian calendar is balanced, every 400 years we omit a total of three leap days. Years that end in “00” but are not a clean multiple of 400, do not have a leap day. The year 2100 does not have a February 29th, so anyone lucky enough to have an ALS like this one in their possession will need to correct the date. This is likely only going to be a problem for the youngest of ALS collectors (looking 87 years down the road) or for the fortunate few who will be willed such a mechanical marvel.

Employing a quad sub dial layout, the dial design is crowded but elegant. The twelve o’clock dial tracks the chronograph minutes while a subtle silver (or gold) hand indicates the remaining power reserve. The sub dials at nine and three display the perpetual calendar information while the six o’clock dial houses the running seconds above a traditional moon phase display that is accurate to a single day every 122 years (definitely a problem for a future generation of owners).

Available in platinum (ref 421.025) or pink gold (ref 421.032), the A. Lange and Sohne 1815 Rattrapante Perpetual Calendar is 41.9 mm wide and 14.7 mm thick and comes mounted to a crocodile leather strap. Few things weaken the knees of serious high-end collectors like platinum cased perpetual calendars, so ALS has delivered in a big way with both this new model and the beautiful calibre L.101.1 functioning within. A. Lange and Sohne is considered to be one of the finest (sometimes THE finest) watch manufacture in the world and this new 1815 Rattrapante Perpetual Calendar serves as witness to the level of expertise, attention to detail, and outright craftsmanship that is required to operate at the top of the watchmaking game.

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