Since the advent of personal timepieces, the quest to build increasingly complicated watches was always constrained by the volume of space available in the watch. Having a multitude of complications in a watch is pointless unless they can be legibly and comprehensibly displayed, and the watch can be reasonably worn. Liberated by the unique design of the iconic Reverso, and after six years of development, Jaeger-LeCoultre has created a world’s first: a double-faced case continuously driven by the in-house Calibre 185, and a double-faced cradle with indications synced and updated by the primary movement every day at the stroke of midnight by an ingenious mechanical system proprietary to Jaeger-LeCoultre.

If executed through conventional means, the 11 complications of the Jaeger-LeCoultre Reverso Hybris Mechanica Calibre 185 Quadriptyque would result in a timepiece far more suited for a desk than a wrist. Thanks to nearly two centuries of expertise and a modern approach to innovation, the new Reverso tells the story of cosmic and terrestrial time within the confines of a 51mm X 31mm X 15mm white gold case.

One of the main protagonists of the watch is the tourbillon complication. Occupying the 7 o’clock position on the recto face of the case, the flying tourbillon (thus called because the absence of an upper bridge allows it to appear as if it is floating), makes one rotation a minute, continuously varying the position of the balance to achieve a single corrected average time measurement. The recto face also displays the indications of a perpetual calendar, a centuries-old mechanism that always displays the correct date despite the irregular number of days each month. It also takes leap years into account, displaying a 29th day in the month of February every four years. Considering the dimensions of the flying tourbillon at 7 o’clock, a new system was developed to position the date display at 5 o’clock.

The minute repeater complication of the watch is activated by the slide of a lever located just above the crown. The melody starts with a series of low notes, correlating to the number of hours. Then comes an alternating couplet of high and low notes, corresponding to the quarter-hours. And in conclusion, a succession of high notes, indicating the number of minutes to be added to the elapsed quarters. In concert, the hours-quarters-minutes chime plays the current time in musical code. The striking mechanism of the Reverso Quadriptyque is completely exposed alongside a secondary time display, indicating the same time as the recto dial, but in a jumping-hours and peripheral minutes format. As the watch strikes the time, setting a symphony of springs, cams, hammers, and gongs into motion, their acoustic report confirms the visual display of the secondary dial.

For the first time ever in the history of mechanical horology, this watch also unites three displays of lunar information — the synodic cycle, the draconic cycle, and the anomalistic cycle. This unique micromechanical combination of indications, located on the interior face of the cradle, allows the determination of eclipse events (both solar and lunar) and rare lunar phenomena such as supermoons. Occupying the top half of the interior face of the cradle is a massive representation of the phases of the moon in the Northern Hemisphere. A laser-engraved moon is progressively covered and revealed by a mobile blue lacquer disc with gold glitter décor, corresponding to the age of the moon in the synodic cycle. While conventional displays of the moon phase accumulate one day of error after 32.5 months, the moon phase display requires only one adjustment after 1,111 years. Just below the moon phase display, on the left, is a counter with a threedimensional micro-sculpted pink-gold sun orbited by a tiny hemispherical moon. This counter shows the draconic cycle, showing when the path of the moon intersects with the orbit of the earth around the sun (known as the ecliptic). Such an intersection takes place twice in each cycle, indicated by the horizontal alignment on the counter of the moon and the sun.

At this time, the moon, earth, and sun are all on the same plane. However, they may not be aligned. For them to be aligned, a phenomenon known as syzygy, an additional condition must be fulfilled — the moon must be either in its new or full phase. When that happens, an eclipse event happens on earth, either a lunar eclipse if the moon is in its full phase, or a solar eclipse if the moon is in its new phase. However, the actual visibility of the eclipse is dependent on various factors such as the geographical position of the viewer. To the right of the draconic cycle counter is a domed representation of the earth, micro-painted in enamel, with a hemispherical moon in eccentric orbit around it.

This counter represents the anomalistic cycle, showing the varying distance between the earth and moon. At its apogee, the moon is at its furthest distance from the earth and is closest at its perigee. When the moon is in its full phase near or at the perigee, an event known as a supermoon occurs, in which the moon can appear to be up to 14 per cent larger than usual in the sky. On the last face of the watch, the exterior face of the cradle, a representation of the phases of the moon in the Southern Hemisphere is shown. Most indications of the moon phase are of the Northern Hemisphere perspective, and the watch’s display of the Southern Hemisphere moon phase on its fourth face is the fulfilment of the Reverso’s fundamental dualism. A starflecked sky chart, engraved and lacquered in a gradient of blue shades, forms the backdrop to the pink-gold moon.

The secret to the watch’s four functioning display faces lies in a solution first used in the 2006 Reverso Hybris Mechanica Grande Complication à Triptyque. Every day at midnight, a pin extends out of the main case movement to activate a mechanical corrector in the cradle, which then advances the cradle displays. The mechanism driving the cradle displays is set directly into the cradle itself, without any additional movement plates that would increase the thickness of the watch. The Jaeger-LeCoultre Reverso Hybris Mechanica Calibre 185 comes in an exceptional presentation box with a built-in mechanism that allows the wearer to set all the calendar and astronomical displays of the watch quickly and intuitively, after a period of being unworn.

A two-position crown on the side of the box is used to first set the number of days that have elapsed since the watch was last worn. With the Quadriptyque set within the correction support frame, the box corrector crown can then be extended to its second position, and wound to rapidly bring the watch to the current date for all calendar and astronomical indications. There is no risk of overcorrecting the watch or damaging the movement, since the entire process is controlled by the box corrector mechanism. Jaeger-LeCoultre’s expertise in ultra-compact watchmaking makes this watch, despite its multiple indications and complications, one of the most wearable high-complication watches of our time. It is powered by the manually wound Jaeger-LeCoultre Calibre 185 with a power reserve of 50 hours. The watch is limited to 10 pieces.