(Pierre-)Louis Berthoud (1754-1813)
Pierre-Louis Berthoud, more widely known as Louis Berthoud, was born in Val-de-Travers in November 1754. He had just turned fifteen when his uncle, Ferdinand Berthoud, invited his young nephew to come to Paris.
(Pierre-)Louis Berthoud, Quarter repeating pocket-watch, Movement No. 2575, Case No. 487, Paris, circa 1804
18k gold, engine-turned case, reeded band, pusher for repeater via the pendant, small slide piece at 1 o’clock to block the repeater pusher.
Enamel dial with Arabic numerals and blued Breguet hands.
The case was originally engine turned but has been well used during its life and the pattern has been considerably worn.
Ten years later, Ferdinand Berthoud retired at Groslay, in the Montmorency valley north of Paris, devoting himself to his research. He entrusted his Parisian workshop to his nephew, Henry Berthoud, who was Louis’ brother.
Large domed crystal. The time is set by opening the bezel and adjusting the hands with the central square the minute hand sits on using the same key used to wind the mainspring wound through the second square at 1:30 through the dial.
Henry committed suicide on June 2, 1783, leaving the Parisian workshop deeply in debt. Ferdinand Berthoud asked Louis to hurry to Paris and restore the business to proper order. Louis Berthoud set out towards Paris early in May 1784. On October 16, 1802, the French government conferred on him the title of “Horloger Mécanicien de la Marine.”
The inner case jacket (or inner dust-cover) is also hinged, and made from brass, hand engraved and gilded.
Full plate movement, key-wound, frosted, gilt, signed, 2 hammers / 2 gongs, chain-fusee, cylinder escapement, three-arm ring balance, sector-shaped, skeletonized, engraved balance cock with floral pattern, diamond end-stone on balance. 134g / Diameter 55 mm
When the inner dust cover is opened the movement can be viewed.
The bezel is opened by levering the bezel with a thumb nail at 1 o’clock.
The movement assembled with enamel dial and hands, but removed from the watch case.
Rear view of the movement showing the barrel, repeater mainspring (below balance wheel) and balance wheel and the surrounding gongs.
The scale with L (lent-slow) and V (vite-fast) is associated to the square in the centre used to adjust the speed of the repeater mechanism.
Underneath the square a pinion turns that meshes with the last wheel in the repeater train. This hole the pinion turns in, drilled into the square would turn eccentrically as the square was rotated altering the penetration between the wheel and pinion. The deeper the penetration the slower the repeater would sound.
Behind the gongs to the left of the image can be seen the fusee.
In the centre of the image one of the hammers can be seen that strikes the gongs announcing the time.
The upper plate sits on pillars and is locked in place by conical pins pushed laterally through the end of the pillars on the plate side. The pillars are riveted into the main-plate.
The escapement is a cylinder (frictional rest), still functioning but no longer as accurate as when it was first made.
The balance wheel top pivot end shake (play) is limited by a diamond end piece.
The quarter repeater mechanism normally hidden under the dial.
The upper lever is pushed into the centre of the movement until the long central finger hits the hour cam that both dictates the number of hours to be sounded as well as releases the quarter rack which is then gathered by the repeater mechanism sounding the hours and then quarters.
In between the main-plate and the dial is a tarnished brass coloured ring that acts as a spacer for the repeater mechanism.
The enamel dial removed from the movement.
The underside of the dial showing the makers name ‘Vincent’ and the rear enameling that was added to ensure even tension between both sides of the dial. The dial is domed and the edges were stoned down to ensure it would sit flush/flat on the movement. Where it was stoned down the enamel was removed and the copper base metal can be seen.
The repeater mechanism main-spring is always kept under tension.
Below the two gongs is the lever that the plunger in the case pushes on to activate the repeater.
With the minute and hour wheels removed the cams that dictate the quarters can be seen.
The hour cam under the star wheel indexed by the pawl at seven o’clock.
All of the repeater levers and cams are made from hardened steel and mirror finished. Over the 200 year life span of the watch is has suffered some wear and scratches through use and manipulation but it still works as a timepiece and repeater today.
The quarter cam assembly is found in the centre of the image. To its right the brass star shaped wheel carries the hours cam that dictates the number of hours that would be struck.
Summary
This Louis Berthoud timepiece, although not of the same quality of production as the Ferdinand Berthoud pocket watch (shown here) it remains a historic representation of an early complicated sonnerie. With the exception of the pillar pins that have been replaced the watch is original and although well used is in good condition.
It is an early quarter repeater with fusee, cylinder escapement, diamond end-stone balance bridge, index regulation, gilded plates with hand engraving, polished steel levers and cams, enamel dial and engined turned case. All of these elements are indicative of classic traditional watchmaking, in a world prior to electricity. The design, engraving, engine turning, polishing, assembling, adjustment would all have been executed manually by hand.
Thanks to Ferdinand Berthoud company for the dates and historical information noted in this page.
GALLERY
In the grid below are both images used in the description of this page plus more. Please click on the image to enlarge and see in full.
To learn more about Ferdinand Berthoud