In many ways, the Logical One is the piece that made enthusiasts first take note of the manufacture of Romain Gauthier. This piece is the final one of a limited series of five examples created exclusively for the United States market between 2018 and 2020.
It features a 43mm yellow gold case that stands 14.5mm tall. It has a satisfying presence on the wrist, and the case has a number of interesting details. The concave bezel and the bulbous midcase are high polished, as are the curved down lugs. The lugs feature a polished outer rim that contains sandblasted recessed interiors. The lugs meet the midcase in a flared and exaggerated way. At 2 o’clock is the crown that sets the time. It is relatively diminutive in scale because it is not designed to manually wind the calibre – this is done with a signed, bat-shaped pusher on the left flank of the case. Engaging this pusher transmits energy to the barrel, giving the movement autonomy for 46 hours.
On the dial side are the offset, overlapping subsidiary registers that display the time and seconds. It is two-part in construction, with the yellow gold base acting to delineate the two. On top of the gold base is the beautiful black, oven-fired enamel dial, with a printed chapter of serif Arabic numerals and markers for minutes, along with a hemispherical detail underlining the brand mark. The subsidiary seconds register follows a similar layout, with a marginally oversized quarter of seconds. The leaf-style seconds hand is golden, as are the skeletonised hour and minutes hands. The two registers all but conceal the train wheels that govern time display.
Underneath this is the balance, finished beautifully in a range of styles including solarisation and bercé polishing, with the watchmakers at the manufacture using this as an opportunity to showcase their mastery with creating precise inner angles.
While the time-telling aspects and the balance are placed on the same level, against the frosted gold of the base plate, on the left-hand side on a slightly lower plane, is the chain and fusee-style system that runs at 4Hz. In the Logical One, Romain Gauthier replaces the fusee with a slowly rotating snail cam, placing it and the mainspring barrel on the same level. This way, force is always transmitted in a straight line, and only one short line of chain is needed. With the advantage of larger chain links, Gauthier further improves efficiency by constructing the links with low-friction, hard-wearing, synthetic rubies. To eliminate potential friction within the mainspring barrel, the mainspring is placed between synthetic sapphire plates, visible on the movement side.
The advantage of the snail cam is that the way it interacts with the balance, even as the latter loses power, the quantum of torque that is supplied to the escapement remains constant, resulting in linear timekeeping. The arrangement is revolutionary, and the 37-jewel movement features several patented design elements. It was all developed at the manufacture of Romain Gauthier in the Vallée de Joux. It is beautifully finished too, with a mirror-polished bridge, precise internal angles, and the manufacturer's signature wheel-within-wheels motif. The baseplate underneath this is satinated, and a screwed-on plaque says “Logical One”.
Studying the constant torque arrangement closer helps understand why the Logical One won the Best Men’s Complication award at the Grand Prix d’Horlogerie de Genève when the watch was launched in 2013.
On the movement side, the frosted bridges have been constructed to offer a glimpse of the wheel train, and it features the kind of precise finishing, including anglage and the finely finished internal angles. Also visible on this side is the power reserve indicator. Plaques bearing the place of origin, the jewel count, and the serial number out of five sit atop the many islands that the bridges form. The display caseback is secured by the same proprietary flathead screws found throughout the piece on the dial and movement side.
The watch comes with a bolstered brown alligator-style leather strap from the brand affixed to its 22mm lugs, secured by a signed, yellow gold buckle that also features beautiful inner angles.
The package includes the presentation box as well as warranty paperwork. Often seen in white metals – white gold to titanium – this example of the Logical One in yellow gold is as arresting as it is unusual.
