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Perpetual Calendars

Perpetual Calenders are found in many top of the range watches, and use a complicated mechanism to present the date, day, month and usually moon phases correctly. The mechanism was first devised by Abrahain-Louis Breguet and is the only mechanism that is able to calculate the exact date whilst taking the differing days of a month into account. Leap years are also accounted for, reducing the number of adjustments that are necessary to keep Perpetual Calenders correct to just three times every four hundred years. It is truly a masterpiece of craftsmanship and miniaturization.

The Gregorian calendar is peppered with uneven months, not to mention the Leap Year that occurs once every four years, presenting the month of February with an extra day. This presents a rather difficult challenge to watchmakers who must reproduce these variations in an intricate mechanical movement. Before the creation of Perpetual Calenders and their integration into watches, many watches used a simple, annual calender that required the wearer to manually adjust the date once every few months to take into account the months that did not have thirty one days. Today, many lower end watches to not possess Perpetual Calenders due to their intricacies and therefore obvious expense. Perpetual Calenders are frequently seen on the more exclusive watches and are a sign of superior craftsmanship. Many watches by names such as IWC Watches, Omega Watches and Rolex Watches boast Perpetual Calenders.

To provide the stunning feat of displaying the date accurately Perpetual Calenders rely on the 'mechanical memory' that is created by some of the most skilled masters of Horology. There are many movement types that can be found behind the glass dome of your timepiece, but the workings for Perpetual Calenders are truly magnificent. The movement runs over a 1461 (4 year) day period ensuring complete accuracy over this time and up until the beginning of a new century that is not a Leap Year. Despite its name, Perpetual Calenders will have to be corrected by one day on March 1st, 2100. It must be pointed out that it is not the mechanism of Perpetual Calenders that insist on this adjustment but our quirky Gregorian Calender!