reguet’s recent 250th anniversary celebrations were the occasion to pay tribute to the eponymous dynasty. Founded in 1775 on Quai de l’Horloge in Paris, for close to a century the company remained in family hands. Throughout an illustrious career, marked by an abiding interest in both the technical and aesthetic aspects of the watch, Abraham-Louis Breguet explored multiple solutions to reduce energy loss caused by friction.

The Breguet Expérimentale 1, the first in a future line of highly technical pieces, is the continuation of this quest. It tackles one of the most insidious enemies that twenty-first-century watchmakers face – magnetism – by transforming it from foe to friend. The groundwork for this technology was laid in the 2000s and a patent filed in 2010. A revolution. At last, a solution had been found for the point in a movement most prone to friction: the balance staff. That solution was the magnetic pivot.

Principles

Before going any further, a look at the escapement, also a source of friction and energy loss. A classic lever escapement, whose entry and exit pallets slide against the escape wheel’s teeth, is energy-intensive and, because the two parts are coupled, directly influences the balance.

The new escapement in the Expérimentale 1 is a constant-force escapement, thanks to the use of magnetic pallets that engage with the two magnetic escape wheels. This system does away with the mechanical energy losses that are inherent to a conventional escapement. Impulses are frictionless and constant, regardless of how much wind is left in the mainspring. This guarantees constant balance amplitude throughout the entire power reserve.

Moving on to the tourbillon and the balance, the tourbillon in the Expérimentale 1 rotates at the “classic” speed of one revolution in 60 seconds around a single axis, as both Breguet and Arnold recommended in their day.

In their pursuit of the perfect marine chronometer, the great minds of horology’s classical era typically opted for a frequency of 21,600 vibrations per hour, for stability of rate. Thanks to the magnetic escapement, the Expérimentale 1 can adopt a high frequency, in this case 10 Hertz, while conserving a large tourbillon cage. Thanks to the magnetic impulses, uncoupled from the rotation of the escape wheel and therefore the rotation of the tourbillon cage, the latter’s inertia is no longer a disturbing factor for the oscillator.

What about the barrels? A movement with an energy-intensive high-frequency balance is often equipped with series-coupled barrels which deliver a longer power reserve (defined by the length of the mainspring). The twin barrels in the Expérimentale 1 are series-coupled. Each contains two stacked mainsprings, separated by a sapphire disc, that deliver 72 hours of power reserve.

Breguet has chosen a regulator-style display to enhance legibility and optimise the volume taken up by the movement. The hour and minute hands are on separate axes, while the seconds hand is mounted on the tourbillon cage. Theoretical chronometric performance is an astounding -1/+1 second per day, which far exceeds even the requirements of the new COSC Excellence standard.

Conclusion

Titanium and silicon, both non-magnetic, are present throughout the Expérimentale 1’s movement. For centuries, watchmakers have been locked in battle against magnetism, a natural enemy of the watch. Here, magnetic forces are intelligently harnessed so that there are no undesirable effects on the overall functioning of the movement.

It’s no secret that “experimental” often rhymes with high price, exclusivity and limited series. The burning question is whether, in the longer term, this technology could equip more “standard” movements and lend itself to serial production. Could it become the ideal “all-in-one” mechanical movement, defending against disruptive forces and providing constant amplitude for the balance, regardless of the amount of power left in the mainspring, hence stable chronometry? Time will tell, but we can say, without hesitation, that the work Abraham-Louis Breguet began 250 years ago continues to this day!