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Conventional wisdom holds that stopping a tourbillon for precise time setting — “hacking” in watchmaking parlance — is a difficult endeavor given the constant rotation of the cage. The hacking tourbillon wristwatch didn’t arrive until 2008, courtesy of the A. Lange & Söhne Cabaret. In fact, hacking of any sort remained a rarity until the last few decades — ironic, since the primary function of the seconds hand has arguably evolved from a way to assess accuracy into an indicator that a watch is running.

Some brands are still in the process of adding stop-seconds features to their basic calibres, and hacking remains scarcer still in wristwatch tourbillons, appearing with regularity only in the last two decades. But building for the waistcoat pocket, historical watchmakers have been stopping tourbillons for almost as long as they’ve been building them, and developed a number of solutions for this problem along the way, each stopping the tourbillon, or merely the seconds, in a different way.

Breguet – stopping the seconds without stopping the watch

Almost 225 years ago to the year, the French Ministry of the Interior granted Abraham-Louis Breguet (1747 – 1823) a patent for his most famous creation, the tourbillon, a clever way to improve a watch’s marks during accuracy testing. For a mechanical watch to keep the same time across all vertical positions, the “balance complete” — comprised of the balance, staff, roller, collet and balance spring — must be carefully “poised” or balanced, which is challenging even with modern technology.

Breguet’s invention rotated all the components most relevant to timekeeping along the same axis as the balance over a short period, meaning, theoretically, any arbitrary vertical position is the same as any other, when measured over a few minutes or more. This was a natural fit for chronometry trials using the Plantamour rating system, which emphasised consistency across positions and became the standard by which fine watches were assessed during the late 19th century.

Hacking seconds wouldn’t become mainstream for more than a century, but A.-L. Breguet had had at least a passing interest in stopping his watches. Many of his watches feature nibs in the case band that halt the balance, up to his most complicated watch, No. 160, while his resonance watches are equipped with two nibs, capable of stopping each balance individually.

Fittingly, Breguet also equipped his finest timekeepers, a series of eight pocket chronometers with four-minute tourbillons, with stoppable seconds, though without stopping the balance.

Rather than hacking the seconds hand by stopping the tourbillon, A.-L. Breguet added a secondary “observation seconds” hand. The four-minute tourbillon drives two pinions, which each turn once per minute. One pinion directly carries the running seconds hand, while a rudimentary vertical clutch sits between the second pinion and the observation seconds hand.

What looks to be a repeater plunger in the pendant actually serves to disconnect this clutch and halt the observation seconds, which can be resumed at the user’s pleasure. The contemporary Breguet Classique 7225 brought the same functionality to the wrist.

A few other early tourbillons, including Breguet tourbillon designs such as No. 2329, stopped a secondary seconds hand too, which also avoids issues restarting non-self-starting escapement varieties like the detent.

Houriet – arresting the third wheel

Jacques-Frédéric Houriet (1743 – 1830) was a watchmaker and — more importantly — movement constructor born just outside of La Chaux-de-Fonds. Ferdinand Berthoud and A-L Breguet hailed from the same general area, and Houriet would work with both, as well as Julien and Pierre Le Roy.

According to J.C. Sabrier’s Jacques-Frédéric Houriet, The Father of Swiss Chronometry, Houriet designed at least 110 different movements, which we know from surviving notes and brass templates represented 77 different designs. His workshop built nine six-minute tourbillon movements for Breguet (nos. 2566 – 2572 and 2728 – 2729).

The foremost manufacturer of pocket chronometers in Switzerland at the time, Houriet applied his experience making bimetallic compensation balances to make some of the first bimetallic thermometers in continental Europe. These we housed in standalone pocket watch like cases, or incorporated onto the dials of his watches, making the bimetallic thermometer something of a calling card for Houriet, alongside the spherical balance spring.

Houriet also designed and built a series of one-minute tourbillon pocket chronometer movements for other customers, which, to my knowledge, were the first with a true stop-tourbillon feature. These followed chronometer conventions with plate-and-pillar construction, chain and fusee, a massive free-sprung compensation balance, and, of course, a spring detent chronometer escapement (though with Houriet’s spherical balance spring rather than a helical one as is typical in chronometers) and his bi-metallic thermometer mounted dial-side.

Opening the bezel, which is necessary to access the time setting square, reveals a tab in the case band. Moving this tab lifts a spring from (or drops it onto) the third wheel, bringing the train to a halt. This mechanism can be seen on a Hunt & Roskell-signed watch in the British Museum’s collection (before 1836) and Urban Jügensen no. 10 (~1930) in Reinhard Meis’s Das Tourbillon.

Watch No. 88 (~1830) by Philippe Du Bois of Le Locle, also featured in Das Tourbillon, features a variation in which the tab directly locks the third wheel. Oddly, Meis makes no mention of this feature, nor does the British Museum, though auction house catalogues caught a “stop feature” on another Dubois watch and a Berthoud Frères watch with a “stop-slide beneath the bezel”.

Stopping the third wheel is less responsive than stopping the balance directly, or even the fourth wheel / tourbillon cage, so it is unclear if this is for time setting or another purpose, such as to remove the tourbillon for adjustment. Also, since the detent escapement is not self starting, a gentle shake is needed to get it going again.

Louis Richard – stopping the cage (and the third wheel)

Swiss chronometer maker Louis Richard (1812-1875) is very famous to very few, including the two collectors who fought a bloody bidding war for his magnum opus at Phillips earlier this year. Watch No. 12, shown below, combines an elaborate constant-force escapement with a one-minute tourbillon. While conceptually similar, Richard’s constant-force escapements vary between examples, and these watches were highly experimental. This explains much of their contemporary appeal.

The escapement comprises three detents: two spring detents and one pivoted detent. Rather than impulsing the balance directly, as in a typical chronometer escapement, the otherwise normal escape wheel charges the pivoted detent, which is locked by the second spring detent. Then, when the balance unlocks the second detent, the pivoted detent impulses the balance.

While force from the escape wheel varies as the mainspring runs down, the fully charged pivoted detent always delivers the same force to the balance. This method is inefficient compared to the chain and fusee as it (intentionally) sacrifices much of the mainspring’s energy for constancy.

It is also even more difficult to manufacture than the already complicated chain and fusee, which explains why it never saw broader adoption despite being theoretically sound (unlike many experimental escapements).

Like Houriet’s tourbillons, No. 12 can be stopped at the third wheel. Turning the fork-tailed screw from M (for marche, meaning “go”) to A (arret, “stop”) allows a spring-loaded pin to fall between the teeth of the third wheel (on the dial side), locking the train.

Additionally, sliding a tab (red, below) in the case band allows the owner to stop the tourbillon cage directly by pivoting a lever (blue) connected to an S-shaped hacking lever on the rear of the watch. This redundancy could be explained by the third wheel lock being for the watchmaker’s benefit — not the owner’s — as it isn’t easily accessible. Locking the third wheel lets the watchmaker remove the tourbillon cage for adjustment without letting down the mainspring.

The hacking lever, used in Chopard tourbillons, Grand Seiko’s Kodo, and too many other modern wristwatches to name, stops the cage instantly, even though the balance continues to beat for some time afterwards — also true of stopping the third wheel. Hacking the fourth wheel, which a one-minute tourbillon cage basically is, is uncommon but not unheard of in non-tourbillon watches, with Daini Seikosha’s cal. 44 of King Seiko fame is probably the best-known example.

Nicole Nielsen – stopping the balance directly

The earliest tourbillon movement that I know of to stop the balance directly is a silver sweep-seconds tourbillon made by Nicole Nielsen for Thomas Russell and Son of Liverpool around 1906, though I wouldn’t necessarily claim it to be the first watch with such a feature. Founded in Le Solliat, Vallée de Joux in 1837 as Nicole & Capt, the company later expanded to London, becoming Nicole, Nielsen & Co. after Danish watchmaker Sophus Emil Nielsen joined in 1870.

As the foremost English tourbillon manufacturer at the turn of the century, Nicole Nielsen built a great variety of tourbillons, including the most complicated historical tourbillon and the first flying tourbillons.

Pressing a pin in the case band pushes the hack into the balance. While the cage’s three pillars will intermittently block the hack, this is a non-issue for stopping the seconds hand at zero. The cage and seconds hand both rotate in sixty seconds, so if the watchmaker applies the seconds hand when the balance is exposed, the balance will always be exposed when the hand is near zero.

George Daniels (1926 – 2011) once described a Nicole Nielsen tourbillon as being “as fine a watch as has ever been made, and one whose performance can hardly be bettered” in Watches (1965). Perhaps unsurprisingly, Daniels used wire hacks in a few of his own tourbillon watches, including the one he left behind, though for an usual reason.

As the mainspring nears exhaustion, a mechanism in the power reserve releases the wire hack, which stops the watch until it is rewound. Daniels believed it was better to stop the watch, and alert the user, than allow it to run sub-optimally. Again the cage pillars were a nonissue as even if the pillars blocked the hack, the pillars would move out of the way shortly, and it didn’t matter where the tourbillon stopped.

However, the pillars were an problem for Helmut Geyer, a watchmaker and movement constructor at Lange Uhren. Mr Geyer’s approach to hacking the tourbillon used an m-shaped spring, based on the logic that one end will always contact the balance, even if the other is blocked by a pillar.

Patented in 2001, Mr Geyer’s invention wouldn’t debut until 2008 with the Cabaret Tourbillon, just after his retirement. The Cabaret Tourbillon was not the first hacking tourbillon, as it is often called, but was the first produced in significant numbers, and Lange’s two-pronged approach to hacking was both novel and useful.

Lange’s sister brand IWC took a similar approach with its tourbillons soon after. Jens Schneider, another member of Lange’s Sax-0-Mat project, deserves particular mention for his brush-hack, using bristles (made from human hair) to stop the balance. Not to forget the pillar-less Exotourbillon, which avoids the issue entirely.

Mr Geyer, along with the previously mentioned tourbillon expert Reinhard Meis, also designed A. Lange & Söhne’s 1997 Sax-0-Mat calibre, which used to heart cam and hammer (invented by Nicole Nielsen, as it happens) to instantly reset the seconds to zero when the crown is pulled. In 2014 Lange combined both of Mr Geyer’s inventions to create a hacking tourbillon with zero-reset seconds in the 1815 Tourbillon.

Gene Clark – stopping at zero

Gunsmith-turned-horologer Gene Clark (1948 – 2006) built four tourbillons — out of seven watches total — in his Pagosa Springs workshop, nestled in the Rocky Mountains. Clark was an extremely skilled workman able to make just about every metal part that went into his watches, from detent and passing springs to, at one point, rolling his own steel mainsprings, though he later switched to Swiss imports. According to a 1988 article in the Horological Times, he alloyed his own gold, creating an hardy 19k gold alloy for his cases and 16k and 22k alloys for escapement components.

Only two things were beyond his ability: free-hand engraving and counting. Clark used a wire hack in his first tourbillon, No. 7 (1897), to stop the balance inside the two minute tourbillon cage. Clark’s second tourbillon, No. 4 (1991), went without a stop feature, focusing on a constant force device instead. His third and fourth tourbillons, however, (Nos. 5 and 32, respectively) featured hacking mechanisms that stopped the watch when the seconds hands reached zero.

On watch No. 5, a button in the case band turns a column wheel that moves a lever towards or away from the fourth wheel (both watches had a fourth wheel which drove the tourbillion). A pin on the fourth wheel collides with the extended lever, stopping the watch with the seconds hand in the same place each time — zero if the hand is put on correctly.

Watch No. 32 eliminates the column wheel, using one button to extend the stop lever, and another button to retract it and restart the watch, a solution that feels more at home with the 18th- and early 19th-century watches that inspired Clark. The Niton Prima, one of last year’s better jumping hours watches, uses the same system, while Grönefeld’s parallax tourbillon puts the stop pin directly on the tourbillon cage. Simple and practical, this is the approach I’d take if I were designing a tourbillon calibre.

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