Ferdinand Berthoud FB 1R Chronometer 1785 Edition

This special edition collection, comprising five unique interpretations of the FB 1R chronometer manufactured by Chronométrie Ferdinand Berthoud, pays tribute to the most important expedition in French naval history, that of the Astrolabe and Boussole frigates in 1785 commanded by the Count of Lapérouse. This voyage was assisted by the chronometers made by Ferdinand Berthoud. Dressed in a patinated bronze case, each of the five unique timepieces from the 1785 edition recalls that of period marine instruments.

A new interpretation of the Chronomètre FB 1R presented at the SIHH 2018, the 1785 edition is a series of five bronze watches – each of which is truly unique due to the use of various artistic patinas – embodying a double homage. The first tribute is paid to Ferdinand Berthoud’s Marine Clock no 7, a major source of technical and aesthetic inspiration for this regulator-type model.

Secondly, the name of the 1785 edition harks back to the famous exploratory round-the-world voyage undertaken by Lapérouse between 1785 and 1788. The presence of bronze with its unique patina as well as calibre FB-T.FC.R are all reminders of the instruments used for measuring time at sea. Marine chronometers and sextants were the only means of calculating longitude and thereby represented decisive factors in the success of their respective expeditions.

Jean-François de Galaup, count de Lapérouse was one of the most illustrious explorers in his nation. His navigational and leadership talents, along with his considerable experience, led Louis XVI to entrust him with the boldest campaign of maritime exploration France had ever undertaken. On August 1st 1785, he sailed from Brest with two frigates, L’Astrolabe and La Boussole. Aboard them were 220 officers, scholars and sailors. Lapérouse took the helm of the Boussole and entrusted the Astrolabe to his second in command, the brilliant officer and navigator Paul-Antoine Fleuriot, Viscount of Langle.

The purpose of this expedition was to circle the globe in order to complete its cartography and to pursue exploration of the Pacific Ocean. The two ships were equipped with the finest measurement and observational instruments of the era, including five marine chronometers by Ferdinand Berthoud, Clockmaker and Mechanic by appointment to the French King and Navy since 1770. During the two and half years of this voyage, Lapérouse and his men crossed the North and South Atlantic, rounded Cape Horn and sailed up to Alaska via Hawaii. They then crossed the world’s widest ocean to reach Macao, travelling up the Chinese coast before heading towards the South Pacific via the Tonga Islands. A few months after a stopover in Australia, in March 1788, they vanished somewhere between the Salomon Islands and the Vanuatu archipelago.

Subsequently, several expeditions launched to seek out Lapérouse’s ships came across traces of the shipwreck. They discovered that the Astrolabe had foundered on the Vanikoro Islands in the Santa Cruz archipelago, while the Boussole had sunk. A few members of the crew survived the double shipwreck. Among other objects found in Vanikora, a sextant was unearthed in 2005, oxidised yet intact after 217 years. Crafted in bronze, this fundamental navigating instrument inspired the patina colours of the 1785 edition.

The FB 1R chronometers in the 1785 edition measure 44 mm in diameter and less than 14 mm thick. The beadblasted case is entirely made of bronze, an alloy chosen for its capacity to acquire a distinctive patina. The five regulator models, numbered Fb 1R.5-1 and FB 1R.5-5, all feature a different colour. This is because each of the de facto unique patinas of these models has been made using a distinct formula, chosen after dozens of trials and tests. The aim was to achieve the desired shades while ensuring their dermo-compatibility in compliance with the REACH regulations of the European Union.

The case features two bronze side shafts in bronze that endow it with a characteristic octagonal shape. The sides bear two portholes at 2 and 11 o’clock, providing a chance to admire the fusee and chain mechanism in action. These two openings are complemented by the glareproofed sapphire crystal case-back affording a pleasing glimpse of the movement finishing. The knurled bronze crown featuring a titanium medallion ensures smooth and easy winding of the movement. The latter is endowed with a 53-hour power reserve.

The chronometers of the 1785 edition are resolutely different to existing regulator-type displays. They feature a mostly solid dial, which is in fact the reverse side of the regulator-display complication plate.

The latter is made of nickel silver, vertically satin-brushed by hand, and feature three small openings. The first provides a reading of the dragging seconds, offset at 2 o’clock. They are displayed on a glareproofed sapphire disc with transfer-printed Arabic numerals, which stand out clearly against the white background. The second reveals an unusual power-reserve display mechanism, highlighted by a wide dial cut-out showing part of the finely sandblasted baseplate.

The third opening is located in the centre of the 12 o’clock minutes counter. Finely chamfered, beadblasted and adorned with gilded chamfers, the central opening provides a fascinating view of the gear train with its hand-engraved pyramid-motif decoration. The latter is inspired by that of a skeletonised astronomical clock by Ferdinand Berthoud that belongs to the L.U.CEUM collection. The seconds appear around the rim of the dial, on a beadblasted and chamfered nickel silver inner bezel ring.

Finally, the nature and origin of the chronometers composing the 1785 edition are flaunted on the large dial, engraved with the inscription “Chronomètre Val-de-Travers Suisses”. More than a mere signature or an appellation of origin, this is a proudly proclaimed affirmation of identity.

A patent has been filed for the highly sophisticated device serving to indicate the power reserve. Visible through an open-worked half-bridge on the case-back side, a truncated cone moves up and down along a worm screw-type arbor attached to the barrel. A mobile arm topped by a roller acts as a feeler spindle and its position on the cone reflects the barrel’s state-of-wind.

The feeler-spindle transmits the information regarding the quantity of energy stored in the barrel to a set of finely chamfered and rhodium-plated levers visible through a cut-out in the regulator-display plate. A spiral-shaped spring at the end of its travel exerts pressure on the base of the power-reserve hand. This spring serves to reduce the play between the various components of this mechanism and to display power reserve with peerless precision. This ingenious mechanism reflects the experimental mindset of Ferdinand Berthoud himself, who revelled in exploring solutions well off the beaten track.

Calibre FB-T.FC.R-2 is one of the rare movements to feature a fusee and chain transmission system, the oldest solution for ensuring a constant-force supply of energy to the escapement. It acts like an automatic reduction gear box, since the torque delivered by the barrel varies according to the state-of-wind.

When the movement is fully wound, the chain is entirely wrapped around the small end of the spindle-shaped fusee and the mainspring is at maximum power. This force dwindles over time and the chain coils around the drum, transitioning from the narrow to the broad end of the fusee. The varying diameter of the fusee compensates for the reduction in mainspring torque. The escapement thus receives a constant supply of energy, thereby equalling out the amplitude of the balance wheel and improving the movement’s precision.

The latter also stems from the tourbillon. Visible on the case-back side only, it comprises 67 parts housed in a 16.5 mm-diameter titanium carriage – itself fixed to a perfectly polished and hand-chamfered arrow-shaped steel arch. To counteract the unbalance of the escapement, two gilded nickel silver poising weights equal out the masses of this large carriage. The tourbillon itself does not indicate the seconds, since the chronometers of the 1785 edition feature a tourbillon with an extremely long and slender gilded bronze seconds hand which glides with remarkable precision and stability.

Together, these two outstanding horological systems, interpreted in accordance with the best practices, endow calibre FB-T.FC.R-2 with chronometer status, a title awarded by the Swiss Official Chronometer Testing Institute (COSC).

The bridges of calibre FB-T.FC.R-2 are made from non-treated nickel silver which is also distinguished by its warm grey colour. It sits particularly well with bronze, a material used for the first time by Chronométrie Ferdinand Berthoud, yet firmly anchored in the history of both watch making and navigation.

The arrow-shaped steel tourbillon bridge is decorated with meticulous care. The upper surface is mirror-polished, the sides are straight-grained and the angles are polished. All components of the titanium tourbillon carriage are entirely chamfered. The power-reserve cone is mirror-polished. The two bridges framing the tourbillon are openworked. The chain, composed of 790 steel parts and measuring 285 cm long, is entirely hand-finished. The sides and stud-pins are satin-brushed, while the flat surfaces are polished.

The finishing operations on the components, whatever their place or function, are done manually by Chronométrie Ferdinand Berthoud using traditional tools.

Technical details
Model: FB 1R Chronometer 1785 Edition
Edition of Five One-of-a-Kind Models in Patinated Bronze

Case
Octagonal case in patinated bronze, featuring two transparent sapphire portholes
Total diameter: 44 mm
Thickness: 13.95 mm
Water resistance: 30 metres
Crown diameter: 9 mm
Numbered edition: FB 1R.5-1 to FB 1R.5-5

Five different types of patina featuring varying degrees of oxidisation and colours
Dynamometric crown (uncoupling system) in patinated bronze, with beadblasted titanium medallion
Screw-in titanium case-back fitted with a glareproofed sapphire pane
Domed flat-topped sapphire crystal glareproofed on both sides

Dial
Regulator-display plate (dial) in hand satin-brushed natural nickel silver
Hours indication on a sapphire disc at 2 o’clock
Minutes subdial at 12 o’clock, openworked and beadblasted, gilded chamfers, black Arabic numerals
Beadblasted nickel silver flat inner bezel ring seconds display
Power-reserve indication at 10 o’clock engraved on the regulator plate from “0_1”
Inscription: “CHRONOMÈTRE VAL-DE-TRAVERS SUISSE”

Hands
Sword-shaped minutes hand in 18-carat gold blued, facetted and openworked
Hours index in blued steel
Power-reserve hand shaped like a blued steel arrow
Blued bronze central sweep-seconds hand

Strap
Rolled-edge hand-sewn patinated chestnut brown alligator leather made from a single swathe of leather (115 x 75 mm, buckle 20 mm) – Various sizes available on request
Titanium pin buckle

Indications
Disc-type hours display at 2 o’clock, pointer-type minutes indication at 12 o’clock, central seconds, power-reserve appearing at 10 o’clock

Movement
Mechanical hand-wound Calibre FB-T.FC.R-2
Diameter: 35.50 mm
Thickness: 9.89 mm
Lignes: 15 ¾
Jewels: 49
Frequency: 21,600 vph (3 Hz)
Power reserve: 53 hours

Tourbillon with fusee and chain (constant force) transmission
– Suspended fusee – winding differential system (PATENT)
– Suspended barrel – Maltese cross stopwork system (PATENT)
– Suspended power reserve – mobile cone system (PATENT)
– Direct-drive tourbillon seconds hand (PATENT)

Regulator-type display
Lever and spiral spring-type power-reserve indicator
Variable-inertia balance incorporating four weights in rhodium-plated nickel silver
Balance-spring with hand-crafted Phillips terminal curve (steel)
Swiss lever escapement
Openworked and engraved nickel silver half-bridges, fitted on stylised polished titanium pillars
Hand finishing in accordance with the highest watch industry standards
Components: 1,158 (including the chain)
Chain: 790 parts
Chain length: 285 mm
Half-bridges: 18
Pillars: 6

Tourbillon
– Rotation:  1 /minute
– Components: 67
– Tourbillon carriage: Ø 16.55 mm (titanium)
– Tourbillon carriage fitted on: 3 polished titanium pillars
– Tourbillon carriage balanced by: 2 gilded nickel silver poising weights
– Balance wheel: Ø 12 mm (copper-beryllium)

Certification
Officially chronometer-certified by the COSC

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.