- Museum number
GOLD CASED LEVER WATCH WITH QUARTER REPEAT, PEDOMETER WIND AND UP-AND-DOWN INDICATION.
Gold case with engine-turned decoration. Pendant operated quarter-repeating work.
The case back consists of a disc snapped into a narrow rim.
The front bezel is also very narrow.
There are no case-maker's or other marks.
The white enamel dial has subsidiaries for seconds and up-and-down indication.
On the back the name 'Noirmont' is fired into the enamel.
Arabic numerals with unusual markings.
Blued-steel Breguet style hour and minute hands, the minute hand now lacking its tip. Blued-steel up-and-down and seconds hands, the latter not original.
Full plate construction with circular gilt-brass plates and five cylindrical pillars. Separate screwed-on cocks and bridges.
Two gilt-brass going barrels independently drive a common intermediate wheel. One of the barrels is fitted with a form of Geneva stop-work which raises a lever to intercept and lock the pedometer weight when the watch is fully wound.
Gilt-brass barrels connected to pedometer winding-barrel. Plain five-wheel train.
In-line lever escapement. All the lift is on the pallets, the locking surfaces being radial. The escape-wheel teeth have oil slots. The fork and roller action may appear, but is not, similar to the Savage-two-pin type. The balance may be a later replacement. It is four armed with two bimetallic strips in a `Z' type arrangement.
- Production date
Diameter: 48.80 millimetres (case)
Diameter: 45.40 millimetres (dial)
Diameter: 43.80 millimetres (movement)
Thickness: 17.20 millimetres
- Curator's comments
- Fom Richard Good
Catalogue of Watches in the British Museum. Volume V
Watches with Lever Escapement
number 5 (Unpublished manuscript)
Made by Abraham Louis Breguet
Paris, started March 1789, sold about 1792
Gold cased, ratchet tooth lever watch with quarter repeat and pedometer wind mechanisms, known as a "perpetuelle".
Signature: Around the edge of the movement 'No 27 Inventé par Breguet à Paris'.
Case: A red gold case, the middle and back decorated with fine engine turning, with a pump pendant to operate the 3-repeating work. The middle is a thin band carrying the hinges for the front and back, there is no inner dome or cuvette. The back made up of a disc snapped into a narrow rim. The front is a narrow rim into which the glass is snapped. There are no casemaker's or other marks.
Dial & Hands: A slightly domed dial, with subsidiary dials for seconds and up-and-down indication. The dial is signed 'Noirmont' on the back. Arabic numerals with unusual markings. Blued-steel Breguet style hour and minute hands, the minute hand now lacking its tip. Blued-steel up-and-down and seconds hands, the latter not original.
Dial-Plate: Between the dial and the front plate is a brass ring or distance piece retained by four dog screws in the front plate, to leave room for the repeating and other work. The dial is held by two short flat feet, and screws which pass through the edge of the distance piece.
Ebauche Marks: None
Frame: A full plate construction, the back plate supported by five turned pillars, and secured by screws. The back plate is pierced with holes for the escapement, the winding work and the mainspring barrels. There are also a number of holes in the plates to enable the mesh of the gearing to be checked visually.
Barrels and Mainsprings:
Barrel: Twin going barrels, the one furthest from the pendant with a form of Geneva stop work on the cover end. The barrel arbor is allowed to turn during winding for a maximum of three turns relative to the barrel. A raised part of the stop piece then contacts a spring lever and applies the catch to hold up the pedometer weight.
Barrels: internal diameter 15.0 mm, height 2.0 mm.
Mainsprings: height 1.8 mm, thickness 0.15 mm.
Barrel Arbors: 4.6 mm, not snailed.
Going Train: There is an intermediate wheel between the two going barrels and the centre pinion. The going train wheels have wide rims but fine teeth. The gilding is of poor quality. All of the wheels have four crossings.
Jewelling: The cone shaped balance pivots run in blind holes in small discs of ruby set in springy steel arms. This is an early example of Breguet's elastic or "parachute" suspension to protect the balance pivots of the watch should it receive a shock. The staff is actually held without endshake between these elastic suspensions. Stop pieces are provided to limit the possible axial movement of each suspension.
Escapement: A ratchet tooth lever escapement (with all the lift on the pallets). An obtuse angle layout. There is no draw since the locking faces are radial. The teeth of the brass escape wheel are thin, and further weakened by slotting for oil retention. The fork and roller action is similar in appearance to a Savage two pin arrangement. Two gold pins are set in the heart shaped end of the fork, and work with a jewelled wedge shaped impulse pallet. Banking for the lever is effected by a slot in the counterpoise fork tail which butts against the escape wheel arbor. Safety action is provided by a small gold roller with passing hollow, and the pointed end of the heart shaped fork. The pallets stones have flat acting faces.
The escape wheel has four crossings.
No of teeth embraced 32.
Balance & Spring: A four-arm brass balance with bimetallic strips secured to the ends of two arms. A similar arrangement to John Arnold's "Z" balance but much lighter. The balance however may be a later replacement.
Balance diameter 14.7 mm, thickness 1.10 mm.
A flat spiral blued steel spring without a terminal curve and nine turns.
Means of Regulation: a key-operated squared arbor in the edge of the movement. On turning the squared arbor a block moves along its threaded portion. Concentric with the balance spring and below it is a brass ring carrying the index pins. An arm on the outside of the ring carries a pin passing into a slot in the block. As soon as the block moves, the ring and thus the index pins move with it. The squared arbor has been repositioned relative to the original arrangement.
Train Counts and Beat Rate:
Great wheels 66 teeth (barrels)
Intermediate wheel 36 pinion 12
Centre wheel 60 pinion 12
Third wheel 64 pinion 8
Fourth wheel 60 pinion 8
Escape wheel 15 pinion 6
Beat Rate: 18,000
Cannon pinion 10
minute pinion 8 minute wheel 30
hour wheel 32
Repeat Mechanism: On depressing the pendant the repeating mainspring is wound by a chain passing onto a pulley on its arbor. The hours are sounded by teeth on a steel 3-arm wheel carried on the repeating mainspring arbor and the quarters by further teeth on this wheel, all acting on a single hammer. All or nothing work is incorporated, acting on the lifting piece on the hammer arbor. The number of hour blows struck is controlled by a cam on a star wheel indexed at each hour by a piece on the cannon pinion. This part of the mechanism operates in the usual way for watch repeating work. The number of quarters repeated is controlled by a cam on the cannon pinion and a rack with three teeth. This rack is gathered by a block on the pivoted steel plate to which the end of the winding chain is attached. One of the three teeth touches the lifting piece in its path and moves the hammer lifting piece out of the path of the teeth on the three-arm steel wheel. The hammer strikes a square-section steel gong mounted on the inside of the case band.
Great wheel 48 (on the barrel arbor)
Second wheel 32 pinion 6
Third wheel 30 pinion 6
Fourth wheel 26 pinion 6
Fifth wheel 21 pinion 6
Fly pinion 8
Winding System: There is no provision for winding the watch other than through the pedometer mechanism. A silver faced lead weight(1) winds the two mainsprings simultaneously through a reduction gear. Each going arbor has a large wheel mounted on it. The pedometer weight is on a squared arbor on which there is also a fine toothed steel ratchet wheel. This wheel is fitted into a recess in a larger brass ratchet wheel which also has fine ratchet teeth on its edge. In a recess in the brass ratchet wheel are two clicks with their springs operating on the steel ratchet wheel. Two more steel clicks work with the teeth on the brass ratchet wheel. When the pedometer weight moves down both ratchet wheels turn and the mainsprings are wound. When the weight moves up only the fine toothed steel ratchet wheel moves past its clicks, the brass wheel remains stationary. A coiled spring is provided to keep the weight roughly in the centre of its travel with the pendant up, with means for setting it up to the correct tension to accomplish this.
Up-and-Down Indicator: The barrel nearest to the pendant has an extended threaded arbor on the cover end, on which runs a threaded steel disc with four slots. A peg set in the barrel cover passes through one of the slots and prevents the disc from turning. Thus when the barrel turns during running, or the arbor during winding, the steel disc moves up or down the threaded arbor. During the winding the disc moves away from the barrel and during running, towards it. A pivoted arm has one end in contact with the top of the disc and the other in contact with a spring loaded cam on the arbor carrying the indicator hand. When fully wound the watch has a maximum reserve of going of some sixty hours.
Case: diameter 48.8 mm, thickness 17.3 mm.
Movement: front plate diameter 41.0mm; back plate diameter 39.6mm; frame height 9.0mm.
Provenance: Formerly in the Ilbert Collection. Ilbert purchased this watch from Malcolm Gardner in 1935
(1) This would have been a platinum weight initially. Platinum was not a valuable metal when Breguet made these watches so there was no reason to turn to lead weights. However in the latter part of the nineteenth century and in this century it would have paid a workman to remove the platinum weight, which had become valuable as scrap, and to make a new one.
Daniels reports in 'The Art of Breguet', p.115 that 31 perpetuelles were made between 1787 and 1791 although some of these were not completed until after 1800. He also says that it probably took one man 2 years to make such a watch. 42 perpetuelles are illustrated in his book of which 35 have lever escapements.
For a similar watch see cat. no. 6 (registration no. 1958,1201.3132).
- Not on display
Latest: 3 (2017)
3 (Feb 1995)
- Acquisition date
- Britain, Europe and Prehistory
- Registration number
- Additional IDs
Previous owner/ex-collection number: CAI.0275 (Ilbert Collection)
Previous owner/ex-collection number: P1 (Ilbert Ledger)