Breguet has unveiled a new version of the Marine Tourbillon Équation Marchante 5887 in 950 platinum to mark the 225th anniversary of the tourbillon.
The stunning dial depicts the night sky on June 26, 1801, when Abraham-Louis Breguet was granted a patent for the groundbreaking regulator.
The two-part construction comprises a sapphire dial with a gradient-blue Grand Feu enamel and a translucent underside.
Also done by hand, a miniature painting in luminescent material portrays the constellations and the Moon in their exact positions at midnight as seen from Paris on the date of receiving the patent.
With a diameter of 43.9mm, the Marine Tourbillon Équation Marchante 5887 represents the spirit of early maritime navigation, which used a sextant and compass, with only the observation of the sky and true solar time as reference points.
It also celebrates Abraham-Louis Breguet's pivotal role in marine chronometry and how his ingenuity earned him the prestigious title, Horloger de la Marine Royale, bestowed by Louis XVIII on Oct 27, 1815.
The legacy is reflected by decorations on Calibre 581DPE. On the compass rose motif, North is symbolised by a stylised fleur de lys in Breguet Gold, as a discreet nod to King Louis XVIII. A hand engraving of the 18th-century ship Royal Louis has been executed on the same gold alloy, which contrasts with the rhodium-plated sky and sea.
The equation of time is a signature Breguet complication that takes into account the difference between conventional mean time and true solar time, which varies by a few minutes each year due to the elliptical shape of the Earth's orbit.
Annually, the two coincide four times and otherwise the difference ranges from -16 to +14 minutes depending on the time of year.
Breguet enables an intuitive reading of the difference between the two reference times, known as the running equation of time, through an additional minutes hand in glass with a gold sun motif.
For an accurate date, the equation of time couples with a perpetual calendar, whose displays are positioned between 9 and 3 o'clock. The equation cam is visible on the tourbillon axis at 5 o'clock while a power reserve indicator is located between 7 and 9.
Ensuring an 80-hour power reserve, the self-winding movement features a platinum peripheral weight with an engraved guilloché "Quai de l'Horloge" motif, inspired by the historic address of Breguet's workshop in Paris.
A limited edition of 25 pieces, the platinum Marine Tourbillon Équation Marchante 5887 can be personalised with the sky chart corresponding to a chosen date and location.
