The most expensive watches tend to have movements capable of measuring more than just the passage of time in hours and minutes. Those extra measures are achieved via the so called “complications” or "grand complications" when several of them are combined together. Common complications in commercial watches are day/date displays, alarms, and chronographs. Other complications might include: perpetual calendars, rattrapante chronographs, sonneries, moon phases, 24 hour dials and multiple time zones. The higher is the number of complications the more difficult is the overall process of designing, making and assembling the movement especially considering the space constraints and this ultimately drives the higher cost of the resulting luxury timepiece.
Most people, however, define complications also other mechanisms that do not add new measures but still increase the complexity of the overall watch movement. Some of those are intended to improve watch accuracy or make the movement more interesting while in operation. In this context the “king” of the complications even if not technically a complication is the tourbillon (or tourbillon escapement).
The tourbillon was first developed toward the end of 18th century and then patented by a French-Swiss watchmaker (Abraham-Louis Breguet) hence the reason for the French origin of the word which means whirlwind. At that time the watchmakers were trying to improve the reliability of the watches and in particular they were trying to counter the effect of gravity on the movement. The challenge was about keeping the movement of the escapement, pallet fork and balance wheel as much regular as possible – refer to our other article “Watch Movements – Beginners Guide” to understand the different parts of a simple movement. Due to the peculiar design of those elements and depending on the position of the watch, the gravity might influence the rotation/movement hence impact the rate of timekeeping.
The physical principle to solve this challenge was then relatively simple – though difficult to design, manufacture and assemble. The main problem is the effect of the gravity when the watch is used in different positions hence the solution is about creating a mechanism that keep the escapement fix no matter what the position of the watch is (gyroscope) or in the case of most tourbillons, about having a mechanism that keeps the escapement rotating continuously at a slow pace (generally about one revolution per minute) so to average out the errors. In fact, the tourbillon is nothing more than a rotating cage that houses the entire escapement system.
Over time different kind of tourbillon complications have been created. The first ones, like the one designed by Breguet, were meant to cope with the fact that pocket watches were kept in a vertical position most of the time. Those first tourbillons however were not perfectly suitable for wristwatches that keep changing from horizontal to vertical position multiple times during the day hence new ones came into play (e.g. inclined tourbillon by Greubel Forsey). A further advancement came with the introduction of the dual-axis tourbillon first invented by Anthony Randall in 1977. In this structure the escapement mechanism rotates around two axes both of which rotate once per minute.
In the ’80 the horology industry has been disrupted by the broad commercialization of quartz watches. Focus went on those new movements while classic mechanical movements were suffering. However, in the early 2000s a series of innovations on the tourbillon complication helped bringing back allure to the mechanical more traditional movements. The true innovation combined with a great marketing effort was actually at the base of the re-flourishing of the traditional movements.
At the beginning of the 21st century Greubel/Forsey and Presher introduced new variations of the tourbillon. Greubel Forsey introduced first the double tourbillon DT30 (2004) and then the quadruple tourbillon QDT (2005). The double tourbillon is made of two cages one inside the other that contain the escapement – the first cage completes a rotation every minute while the second rotates every four minutes. The quadruple tourbillon is a combination of two separate and interlinked double tourbillions. At the same time (2004) Thomas Prescher developed the first triple-axis tourbillon then adapted for wristwatches by Aaron Becsei (2007).
Interestingly, it has not been proven that those even more complicated tourbillons can dramatically improve the watch accuracy. The new developments, in fact, have been more a showcase of engineering brilliance and artistic invention rather than a move toward better watch accuracy. They were essentially a way for the watchmakers to showcase their expertise and unique craftsmanship qualities. Under this consideration, it is worth mentioning the flying tourbillon which simply allows a better view of the mechanics and movement via the elimination of the bridge or cock (metal element that supports the tourbillon from the top). For the very same reason most of the watches with a tourbillon typically allow this element to be seen through a window more or less glorified in the face of the watch. An incredible machine is the Vianney Halter Deep Space Tourbillon in which the tourbillon is not just the heart and soul of the watch but the watch itself. As in everything exceptions are still present and, for example, the Patek Philippe 5216 is very subtle and it has a hidden tourbillon – just mentioned on the dial.
Interesting, one of the real advantages of a tourbillon is that it can act as a second hand as it generally rotates once per minute. Some tourbillon, however, rotate at a different speed – for example: Vianney Halter has one axe rotating in 40 seconds, Girard-Perregaux Tri-Axial Tourbillon has the external carriage rotating in 30 seconds, Jaeger-LeCoultre’s Calibre 177 has gyrotourbillon with an internal carriage which rotates in 24 seconds and Greubel Forsey's 24-second tourbillon rotates in 24 seconds.
Due to the complexity of the tourbillon in terms of both manufacture of the different elements as well as assembly operation, only a small number of watch manufacturers are capable of developing and producing it. At the beginning this was a specialty of the Swiss or European in general but nowadays more and more Asian companies are capable and start mastering this complication. The complications made in Asia (mainly China) are available at a fraction of the price of the Swiss ones. Their quality, however, is not (yet) the same especially in terms of material finish as well as overall movement accuracy.
An interesting variation of the tourbillon is the carrousel. The two complications are very similar and both intend to offset the effect of gravity on the watch. Like the tourbillon, a carrousel is a mechanism that put in continuous rotation the balance wheel and the escapement; however, there is one main difference between the two mechanisms. In the tourbillon one gear (the fourth wheel) activates both the rotation of the tourbillon and the escapement. Conversely, in the carrousel those two movements are decoupled and one gear (fourth wheel) activates the escapement while the rotation of the entire escapement movement is activated via a secondary train of gears.
This is not a new complication (invented in 1892) and while it was originally designed as a more robust alternative to the tourbillon, it is now perceived by some watchmakers as a cheaper alternative to the tourbillon while by other as a more exclusive one (considering the more widespread use of tourbillon vs carrousel). Blacpain is among the watch manufacturers who believe on the carrousel and they introduced multiple collections with this complication – they even introduced a timepiece which features both a tourbillon and a carrousel (Blancpain Tourbillon Carrousel).
In conclusion, the tourbillon and its variant the carrousel are both an amazing combination of artistic and engineering efforts. They were originally meant to improve the accuracy of the measure of passage of time (engineer effort) though today they represent essentially a unique embellishment of the watch (artistic effort). Among the most artistic watches we can admire the Jacob & Co. Astronomia Tourbillon in which the triple-axis tourbillon moves around the entire dial each 20 minutes as well as the Richard Mille RM 19-02 Tourbillon Fleur in which the tourbillon is shown through the blossoming of a magnolia flower.
While the tourbillon is still an almost exclusivity of Swiss/European watchmakers, the Asian complications are getting better and better. This means that soon or later tourbillons might become a more common feature hence lose their prestige and market value. Said that, they still represent the incredible evolution of the watch and showcase the craftsmanship that make mechanical movements so fascinating and still relevant and meaningful to many of us.