Cartier’s revolutionary Rotonde de Cartier Astromystérieux and ultra-sophisticated Drive collection stole the show at this year’s SIHH. Carole Forestier-Kasapi, head of the maison’s fine watchmaking division, explains why.

For more than a century, Cartier has played magician to the masses, enthralling the horological fraternity with its mystery clocks and watches, so named because their hands seemed to float in mid-air, without any apparent connection to the movement. In reality, the hands are mounted on transparent rotating discs with toothed edges that mesh with the wheels of the movement. The first of these, the Model A clock, rolled off the factory floor in 1912 (prior to the invention of synthetic sapphire crystals, clear solid crystal was used).

More recently, in 2013, Cartier released the Rotonde de Cartier Mysterious Hours, a watch with an off-centre dial bearing a basic mystery movement. We say “basic” because a more complex variety, the Rotonde de Cartier Mysterious Double Tourbillon, was unveiled the same year. As the name implies, the mystery movement comprises two tourbillons. One is mounted on a sapphire disc and makes a complete revolution on its own axis in one minute. As for the second tourbillon, the entire sapphire disc acts as a tourbillon carriage, and makes a full turn every five minutes.

This year, the maison took the mystery concept to the next level with the 100-piece limited edition Rotonde de Cartier Astromystérieux. In a no-holds barred instance of exhibitionism, the main components of the movement — the mainspring barrel, gear train, balance wheel and escapement — are on full display. The entire assembly then makes a complete rotation around the dial in 60 minutes, making it a 60-minute central tourbillon.

Beaming as she introduces the watch, Carole Forestier-Kasapi, head of Cartier’s fine watchmaking division, proclaims: “I’m proud of this movement because this complication doesn’t exist. It’s a new complication, a central tourbillon with all the gear trains and barrel in the rotating cage.” She should know. The Astromystérieux, in a way, represents the culmination of her almost two-decadelong quest to produce a central tourbillon. It began in the late 1990s, when she was part of an elite team of watchmakers that created Ulysse Nardin’s revolutionary Freak watch. The Freak, by comparison, has a cantilevered flying tourbillon carriage that contains most of the gear train, along with the balance wheel and escapement.

The key difference, of course, is the use of the mystery concept. Here, Forestier- Kasapi employs a system comprising four sapphire discs. The discs separate the functions of the movement into four categories: hours, minutes, winding and time-setting/tourbillon. The uppermost disc houses the hour hand. Below that, the second disc bears the minute hand, which is adjoined to the mainspring barrel, gear train, balance wheel and escapement. The third disc is reserved for winding, and the fourth and bottommost disc functions as a base plate, carrying Forestier-Kasapi: [The Astromystérieux is] a new complication, a central tourbillon with all the gear trains and barrel in the rotating cage the entire assembly.

Now, how exactly is the watch wound and the time set? First, the winding operation. Under a patented system, the crown is connected to the barrel only when it is being wound. When you turn the crown to wind the watch, a pinion engages the winding disc. On this disc, there is a fixed wheel that is linked to the ratchet (or winding wheel), which then winds the barrel. When the crown is not in use, the pinion disengages.

Next is time-setting. When the watch is running normally, a patented lever blocks the fourth disc so that the fixed centre wheel that it harbours can act as the tourbillon rotating point. When the crown is pulled out to set the time, the lever frees the disc. Consequently, the second disc is also freed, allowing the time to be adjusted (in either direction) without driving the movement assembly around the fixed wheel. Instead, it rotates with the movement. When the crown is pushed in, the disc is once again locked, allowing the movement to continue rotating on its pivot point.

Forestier-Kasapi took great pains to maintain the level of refinement that Cartier is known for. The watch is housed in a 43.5mm palladium case with a height of only 12mm. “Even though it’s complicated, we kept the elegance of the watch,” she says. Of course, there was the need to ensure its reliability as well. “Because the tourbillon has a weight of 3.8g, the whole cage moves when it sustains lateral shocks. This is normal. The gear train can’t absorb this shock, so we added lateral shock absorbers.”

Speaking of refinement, the maison’s other highlight of the year is its sublime Drive de Cartier collection, which takes inspiration from the world of motoring. In contrast to last year’s unisex Clé de Cartier, the Drive is resolutely masculine, with a cushion-shaped case influenced by the chassis of 1960s sports cars, sub-dials reminiscent of dashboard instruments, guilloché patterns resembling radiator grilles and winding crowns shaped like bolts. This is not Cartier’s first collection to draw inspiration from automobile design; The Roadster, launched in 2001, boasted a prominent crown redolent of 1960s Corvette spinner wheels and bullet- shaped side skirts.

“Cartier continues to explore shapes,” explains Forestier-Kasapi. “[This cushion shape] is like a mix between the Tank and the Rotonde.” Three models with different complications anchor the debut collection: a small seconds with day/night indicator (in steel or pink gold), second time zone (also in steel or pink gold) and flying tourbillon (only pink gold). But why a new collection so soon after the launch of Clé? “Clé is a pillar with different sizes for men and women. This one has only one size. It wouldn’t be your first purchase at Cartier. It’s similar to the Rotonde in that you have fine watchmaking elements such as the flying tourbillon, but there are also steel versions.”

The Drive was very well received by industry professionals at the SIHH, and we have no doubt that the all-round appeal — at least of the small seconds model — will translate into solid sales.

Besides chronicling developments in the luxury watch industry, Aaron De Silva also runs The Time Traveller SG on Instagram (@thetimetravellersg) and Facebook (www.facebook.com/thetimetravellersg)

This article appeared in the Options of Issue 758 (Dec 12) of The Edge Singapore.