Derreck Howell

As far as mens watches go, no other mechanical timepiece will match the Ulysse Nardin Perpetual Calendars with Dual Time functions – 5.3 cm3 of mechanical excellence protected by 3 patents :

1. Patent No. CH680630 – Quick setting mechanism
2. Patent No. CH685965 – GMT± the ultimate travel watch
3. Patent No. CH688671 -Oversized date display

For mechanical perpetual calendars evolution seems to have ended some 200 years ago with Abraham Louis Breguet. Since that heroic époque, watchmakers have contented themselves with new interpretations of those wonderful past inventions. Then came Dr. Ludwig Oechslin… Anthropologist, scientist, university professor and master watchmaker all in one. Ludwig is known for his ability to provide the most practical solutions to the most complex challenges with the simplest strokes of genius.

Ulysse Nardin’s Perpetual Calendar with Dual Time function represents the world’s most functional perpetual calendar. In the history of this complication, the GMT± Perpetual is the only watch to offer users the ability to correct instantly all of its calendar displays using only the watch crown – and should you advance the date too far forwards or should you travel to a westbound time zone, it is the only perpetual calendar that allows you to simultaneously turn all calendar  displays backwards.

What is a Perpetual Calendar ?

All systems have their idiosyncrasies. The problem lies in our need to divide the true solar year into equal units of time. The true solar length of a year is 365 days, 5 hours, 48 minutes and 46 seconds. With the Gregorian calendar, every four years we have a significant overage of time. This excess is compensated for by the addition of February 29 on leap years – but because February 29 actually overcompensates for this discrepancy, every 100 years it is omitted. Thus, because this is, in turn, slight under compensation, the leap year is left in the calendar every 400 years. Perpetual calendars not only provide all calendar information, but they are pre-programmed to automatically correct for 30/31-day months, the 28 days in February as well as for the extra day during leap years.

How it works

Look at the dial of any Ulysse Nardin perpetual calendar and your mind will quickly embrace the pure systematic logic of its displays. The day of the week is situated in an aperture just to the left of the centrally-mounted hour and minute hands, while the month is located in an aperture to the right. The two-digit year is displayed at 6 o’clock and the instantaneously jumping big date mechanism is located in two separate apertures at 2 o’clock. The home time indicator is centrally-mounted and is read from an arrow indicator against a 24-hour chapter ring at the perimeter of the dial. The pushers at 4 and 8 o’clock control the GMT-local time indicator. Press the pusher at 4 o’clock and the watch’s main hour hand will leap backwards. Press the opposite pusher and it will advance at one hour increments per push. In scenarios where you set the local time backwards and the hour hand crosses midnight, all the perpetual calendar information will correspondingly leap backwards by one day. Which means, if  you are on a westbound flight that departs just after midnight on New Year’s Eve, as you readjust your watch time, the day, date,month and even the year indicators will roll back. What this also means is that,wherever you are in the world, you can adjust your watch to local time without removing it or even looking at it – using the plus/minus pushers yourwatch will automatically ensure that all calendar information is correct.

The Program Wheel

The heart of each Ulysse Nardin perpetual calendar is a four level wheel called the program wheel. This masterpiece of epicyclical gearing sits between the 24-hour wheel and the watch big date mechanism. The program wheel is activated daily by a unique tooth of the lower 24-hour wheel to advance one notch of the date wheel. The three long teeth of the upper level of the 24-hour wheel activate the program wheel to advance the additional notches of the date wheel: in months that have only 30 days and not 31, at 9pm on the last day of the month the date will change from 30 to 31, at midnight the date will instantaneously change from 31 to the irst of the new month. On February 28, at 9pm the date will change to 29, at 10pm to 30, at 11pm to 31 and at midnight it will instantaneously leap to the irst day of the new month. During a leap year, on February 29 the date will change to the 30th at 9pm, at 10pm to 31 and at midnight to the 1st day of March. The big date mechanism of the movement directly engages and turns the months which in turn engages and turns the lower digit year indicator which in turn engages and turns the upper digit year indicator, all using gearwheels – flawless.

Dual Time Functions

There are 24 time zones on Earth so that each region of the world can optimize daylight hours and rest during night hours. These 24 zones were established in 1884 when the President of the United States met in Washington D.C. with 41 delegates from around the world for the International Meridian Conference. It was decided that the prime meridian line would be drawn lengthwise across the globe passing directly through the Royal Observatory in Greenwich, England. The starting point for civil time would be Greenwich Mean Time (GMT). The Earth was then divided into sections of 24 time zones deined by longitude.

 “BECAUSE PERPETUAL CALENDARS TRANSLATE COMPLEX MATHEMATICAL RELATIONSHIPS INTO VISUAL REFERENCES, THEY ARE ESSENTIALLY ABOUT THE THEORY  OF MATHEMATICS. THEY ARE ABOUT CREATING PROPORTIONS, FINDING UNITIES AND REPRESENTING REALLY COMPLEX NUMBERS THROUGH THE RELATIONSHIPS.” – Ludwig Oechsli

Local Time And Home Time

The problem with traditional watches that display only one time zone is that you have no reference to the time in your home city when you travel. A frequent traveler needs to be able to read local time (time at his current location) as well as home time (time in his home city). Local time display allows him to function within the work day of his new location. However without a display for home time, should he need to call his own office or even telephone his wife, he is dependent on his ability to add or subtract the correct number of hours to determine the time at home.

Evolving Style

For Ulysse Nardin’s 150th anniversary, the Master of Innovation created the Perpetual Ludwig, the 1rst perpetual calendar in watch history to allow forward and backward adjustments of all calendar displays. Another 1rst was the GMT±Perpetual, launched in 1999 including dual time functions in addition. Introduced in 2005, Ulysse Nardin’s Quadrato combines all of the technical might of the manufacture’s GMT± Perpetual Calendar mechanism and places it inside of the most contemporary case designs.

Ulysse Nardin’s Perpetual Calendar  - MSRP $56,900