The most complicated and expensive watch in the world, the Patek Philippe Henry Graves Jr. Supercomplication started in 1925 and completed in 1932 has fetched the amount of 20.6 Million Swiss Francs at Sotheby's in Geneva just minutes ago.

This exceptional timepiece is a gold, double dial and double open-faced, minute repeating clockwatch with Westminster chimes, grande and petite sonnerie, split seconds chronograph, registers for 60-minutes and 12-hours, perpetual calendar accurate to the year 2100, moon-phases, equation of time, dual power reserve for striking and going trains, mean and sidereal time, central alarm, indications for times of sunrise/sunset and a celestial chart for the night time sky of New York City at 40 degrees 41.0 minutes North latitude.

Accompanied by the original fitted tulipwood box inlaid with ebony and centered by a mother-of-pearl panel engraved with the arms of Henry Graves, Jr. Also accompanied by the Patek Philippe Certificate of Origin and an Extract from the Archives of Patek Philippe.

The Henry Graves Jr. Supercomplication movement is unique. Patek Philippe ensured that each complication was designed specifically for this watch. Complex watch movements usually consisted of complications that were added to a simpler base calibre, however, the Supercomplication’s calibre was developed specifically for this single watch. The Supercomplication required the expertise of some of the finest watchmakers of the period, each skilled in the execution of particular components. These master makers had to work together to ensure that all complications within the watch were seamlessly combined with one another and presented in a case and with a dial of the finest design. After all, this watch was no mere flight of fancy; it was a special order and had to please its patron. This unique collaboration resulted in a watch that was not only the most complex in the world, but was also a timepiece of exceptional aesthetic beauty.

DETAILS ON THE EXCEPTIONAL HENRY GRAVES JR. SUPERCOMPLICATION

THE SIDEREAL DIAL

The sidereal time dial was made between 1929 and 1932 from a gold plate with silvered finish. The three subsidiary dials for sunrise, sunset, and subsidiary sidereal seconds were recessed by circular engraving. The plate was then engraved and enamelled. Above the subsidiary sidereal seconds, the equation of time sector indicates the difference between the minutes of mean time and sidereal time. The sky chart is also made from a gold disc and is overlaid with champlevé blue enamel. The archives of Stern Frères show that Patek Philippe supplied the gold for the dial and paid 110 Francs for its construction. The Stern Frères archives still retain a copy of the original drawings for the dial which were submitted to Henry Graves, Jr. for his approval. The drawings appear in what is known as Stern Frères special design book.

Dial details:
Gold dial plate with silvered finish, black enamel Arabic dauphine numerals, outer minute track, large aperture revealing the sky chart surrounded with the cardinal points, the sky chart composed of a champlevé blue enamel over gold stars à paillons depicting approximately 450 stars and a magnificent representation of the Milky Way, the whole of the night sky for the exact longitude of Mr. Graves’ Manhattan apartment overlooking Central Park on Fifth Avenue, three sunken subsidiary dials for times of sunrise and  sunset in New York, and seconds combined with equation of time scale, ‘pear’ shaped blued steel hands, the dial plate engraved and enamelled and with large personal inscription reading “Made for Henry Graves Jr, New York 1932 by Patek, Philippe & Co. Geneva, Switzerland.”

THE MEAN TIME DIAL

The mean time dial was made by Stern Frères S.A. between 1929 and 1930 and is white enamel. The perfect aesthetics of the dial mask the extreme complexity of its construction. The dial has to accommodate seven layers of hands - the two split seconds hands, hour hand, minute hand, alarm hand, and double hands within either power reserve subsidiaries - all of which have to seamlessly glide above one another. In order to accommodate the unprecedented number of hands, the subsidiary dials are double sunk, and each are made from two separate enamel sections with their relevant calibrations. This allows extra depth to the dial, keeping the overall height between crystal and dial surface to a minimum and thereby minimizing the overall depth of the watch.

Dial details:
White enamel dial, black enamel radial Roman numerals chiffres Romaines regardants, style Genève, outer track for minutes and chronograph seconds indication for fifths of a second, double-sunk subsidiary dials for 60-minute and 12-hour registers combined with power reserves for striking and going trains respectively, further double-sunk subsidiary dial for subsidiary seconds and date, apertures for day, month and moon-phases, Breguet hour and minute hands, the subsidiary dials with feuille shaped hands, gold alarm indicator hand, all other hands blued steel.

THE MOVEMENT

TIER 1

The movement's core tier is double sided. Each side of the ocre accomodates an additional tier, thereby making a total of three tiers.

The movement: 25''' damascened, two train, multi-layered plates with 70 jewels, signed and numbered on the movement band.

Tier 1

Main plate with lever escapement, three first wheels of 14k gold, bi-metallic compensation balance, with gold regulating screws, adjusted to heat, cold, isochronism and five positions, unique balance regulator with aperture enabling regulation concealed under bezel, striking mechanism with two barrels, Westminster-type carillon, grande and petite sonnerie, with four hammer's striking four gongs, mean time train, power reserves for movement and strike, both chronograph mechanisms visible to back-hyphen plate of central tier.

The chronograph is executed in a classic manner, however this complication utilizes a 12-hour register which is rarely seen on Patek Philippe watches. It is also notable that the chronograph function has a 60-minute register which is considerably more complex to integrate than the more standard 30-minute register.

The grande sonnerie includes four hammers that strike four gongs to sound the passing hours and Westminster quarter hours, the petite sonnerie when activated merely strikes the passing Westminster quarter hours.

The alarm employs a fifth hammer and a fifth gong to ring the alarm.

Tier 2 -
Under Mean Time Dial

Plate with alarm, spring and lever layout for time and alarm triple-setting system, calendar, and moon-phases.

The perpetual calendar is unusually displayed with the day of the week and month of the year both shown in rectangular windows.

Tier 3 -
Under Sidereal Time Dial

Sidereal time train, sky chart mechanism, cams for equation of time, sunrise and sunset.

The Sidereal Time train is constructed with three main wheels and makes one full revolution every sidereal day. The Supercomplication provides the complete sidereal time with hours, minutes and seconds indicated. This is the most accurate manner to display Sidereal time but also the most complex.

The Sky Chart mechanism comprises the display plate itself with three wheels and one gear, all connected to the sidereal time and adjustable through the crown's hand setting function.

THE CASE

The case of the Supercomplication was made by Luc Rochat of L’Abbaye in the Vallée de Joux. The case is 73.2mm in diameter, 35mm thick including the crystals and weighs 535g (1 lb, 3 oz). The case by itself weighs an impressive 250g. The double open-faced case is of classic bassine design. Both bezels are impressively thick to accommodate the depth of the dials and their hands. Each bezel has a concealed hinge, which represents the highest quality of such design.

Despite the watch’s impressive size, it is exceptionally well proportioned; this is a testament to the careful planning and extraordinary collaboration between the master watchmakers, dial makers, and case maker who, between them, ensured that every cubic millimeter of space was used with the greatest efficiency. Almost five years were required from the design of the case to its final delivery, during which time hundreds of adjustments were made to ensure every function allowed by the slides and pushers was precise and smooth.

The case incorporates 13 operational functions. Facing the watch from the mean time side and running around the case in a clockwise direction from the crown these are:
1. winding device, turning to one side for the main barrel and to the other side for the chime
2. pulling the crown, first position for the mean time, second position for the sidereal time setting
3. chronograph main start/stop coaxial device
4. moon-phase adjuster
5. alarm winding sliding device
6. petite/grande sonnerie selection slide
7. minute repeat trigger slide
8. adjuster for months of the year
9. adjuster for days of the week
10.  adjuster for date of the month
11. the strike/silent option, selected via a slide
12. the split device pusher
13. pusher to engage hand-setting when crown is pulled out

SUMMARY OF THE MAJOR FUNCTIONS

Perpetual Calendar with Moon-Phases

The perpetual calendar shows the correct day of the week, date of the month and month of the year regardless of the length of the month. It also automatically adjusts for the leap year. The aperture for moon-phases shows the correct phase and age of the moon.

Since the duration of the Solar year is 365 days, 5 hours, 48 minutes and 48 seconds and the mean year is 365 days, an extra year is added every four years (leap year) and a further adjustment is made with the omission of a leap year every four centuries. According to the Gregorian calendar reforms of 1582, century years that are divisible by 400 without remainder are to be considered leap years. Consequently, the perpetual calendar of the Supercomplication will be accurate until the year 2100, when the calendar will need to be readjusted for the first time.

The Westminster Chimes, Repeater and Alarm

Grande Sonnerie with Westminster chimes. Selected via a slide on the case band, this function strikes the hours and quarters at every quarter. The five gongs hammer for the carillon are separate from the alarm.

Petite Sonnerie selected via the slide on the case band, this function strikes the passing quarter hours.

Minute Repeater Selected on demand via the case band, the watch strikes the passing quarter hours and minutes.

The Westminster chime, made famous by the Westminster London clock popularly known as ‘Big Ben,’ was first used in St. Mary’s Church, Cambridge in 1793. The chime tune itself was taken from the fifth bar of Handel’s aria from the Messiah, “I know that my Redeemer liveth.”

Split Seconds chronograph

The split seconds chronograph can be used to time up to two events at the same time. The chronograph is started, stopped and reset via the pusher at the center of the winding crown. When the chronograph is running, the split pusher which is located in the case band between 10 and 11 o’clock (when looking at the mean time dial) can be pressed to stop one of the central chronograph seconds hands, leaving the other to continue alone. Whilst the chronograph is running, minutes elapsed will be counted on the subsidiary dial to the right and hours to the left on the mean time dial.

Sidereal Time and Equation of Time

The Henry Graves Jr. Supercomplication has hours, minutes and seconds of sidereal time, the time of sunrise and sunset (calibrated for New York City) and the equation of time. This sidereal complication requires a transmission ratio of exactly 1.0027379092, which is driven by a 62 tooth wheel on the arbor of the fourth wheel.

Sidereal time is based on the amount of time it takes the Earth to make two consecutive transitions of a meridian by a fixed star. By measuring the transits of a fixed star, one is able to measure the actual time it takes for the Earth to turn on its axis. This period of time is known as a sidereal day which is approximately 23 hours, 56 minutes and 4.1 seconds.

The equation of time indicator on the Supercomplication watch is calibrated to show the difference between apparent solar time (the time as indicated by a sundial) and mean time (the average of solar time). Since the Earth is in an elliptical orbit, the difference between mean and solar time ranges from plus 14 minutes 59 seconds to minus 16 minutes 15 seconds. Solar time agrees with mean time on or about 15th April, 15th June, 31st August, and 24th December.
 
The Supercomplication watch indicates the equation of time on a sector-shaped scale with calibrations for plus/minus 17 minutes. The equation of time mechanism is driven by an arbor that protrudes through the movement from the calendar mechanism.

The spelling ‘sideral’ on the dial of the watch is the French form of the word; the English spelling being ‘sidereal.’

The Star Chart

The Supercomplication’s star chart rotates anti-clockwise behind the oval aperture of the dial. The shape of the aperture allows one to see the night sky as seen from New York City, complete with magnitudes of the stars and the Milky Way.

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