- Museum number
MOVEMENT, DIAL AND DUST-CAP OF A LEVER WATCH WITH QUARTER-REPEAT AND DATE INDICATOR.
Pendant-operated quarter repeat.
Tavan lever-escapement with compensation-curb.
White enamel dial with subsidiary day-of-month.
Hour and minute hands missing; gold date-indicator.
- Production date
Diameter: 39.30 millimetres (dust-cap)
Diameter: 45.60 millimetres
Thickness: 20.50 millimetres
- Curator's comments
- Comment from Richard Good, Catalogue of Watches in the British Museum. Vol. V (Unpublished manuscript)
Jean-George Remond & Cie (1)
Geneva c. 1810
Movement of a watch with a Tavan-type(2) pin-wheel lever escapement, calendar and quarter repeat mechanisms.
Signature: On the dial 'Remond & Compe', on the dust-cap 'Jn Ge Remond & Ce A GENEVE' and on the back plate 'Jn Ge Remond'.
Case: Missing. The polished steel curved spring catch is mounted on the front plate and retained by screw.
Dial & Hands: Flat dial with Arabic numerals and a subsidiary dial for the date, the odd dates numbered and the even dates marked with a dot. Hair line cracks on the dial. The hour and minute hands are missing but the gold date hand survives.
Dial-plate: A wide separate gilded rim, engraved with foliate decoration on the outside and attached to the movement by three dog screws mounted in the front plate. The rim is cut away to clear the hinge block which is screwed directly to the front plate. A connecting portion of dial plate below the hinge block is scratched 'Pieronis T? M 29 4 bre 1856'. The dial is secured by screws through the edge of the rim.
Dust-cap: A gilded brass dust-cap is retained by a straight sliding blued-steel bar running diametrically across the cap locking on two studs on the back plate.(3)
Ebauche Marks: None.
Frame: Full plate construction, the back plate supported by four plain pillars secured by pins. Separate cocks for the balance, pallets and escape wheel. The pallet cock is not gilded. Separate potences for the balance and the pallets. Below the escape wheel on the back plate a turned groove provides clearance for the pins mounted on the underside of the wheel. A double ended cock for the third and fourth wheel pinions mounted on the front face of the front plate above two circular apertures. The blued-steel set-up ratchet and click are mounted on the back plate.
Fusee, Barrel and Mainspring:
Fusee: 5 1/3 - turn fusee without maintaining power.
Barrel: flanged, internal diameter 15.3 mm, height 3.0 mm.
Mainspring: height 2.6 mm, thickness 0.21 mm.
Barrel Arbor: diameter 4.3 mm, not snailed.
Train: Polished brass wheels, the centre wheel with five crossings, the third and fourth wheels with four crossings.
Jewelling: Jewelled bearings with ruby endstones for the balance only. The balance cock endstone is held in position by a large blued-steel coqueret.
Escapement: A variant of a Tavan pin-wheel lever escapement with a polished steel escape wheel with four crossings. The cylindrical gold pins (diameter 0.18 mm) are set at right angles to the rim, spaced alternately on both faces of the escape wheel rim. The long lever assembly (16.5 mm) is of polished steel. The pallets are formed at the end of lever arms, the pallet acting with the pins on the underside of the escape wheel is integral with the arm, boss and fork of the lever, and operates from the outside of the escape wheel. The pallet which acts with the pins on the uppermost side of the escape wheel operates from within the diameter of the escape wheel and is formed at the end of an arm made from a separate piece with a boss, mounted above the boss of the lever. This pallet arm is box cranked to clear the pins on the uppermost side of the escape wheel. The lever assembly is presumable constructed in this way to make it adjustable. A steel dart, integral with a shouldered stud, is riveted below the square bottomed fork of the lever.
The pallet arbor with an integral collar at the top end, passes through the bosses of the lever assembly and is threaded into a squared nut with an integral collar below.
The impulse pin is a pivoted brass roller with a steel arbor pivoting between a boss below the balance and a projection from a brass collar which is itself effectively the roller on the balance staff. An equal impulse escapement with all the lift on the pallets. There appears to be draw on the pallet operating on the pins on the underside of the escape wheel only.(4)
Balance and Spring: A rounded-rim, three-arm brass balance, diameter 16.1 mm, thickness 0.75 mm. Flat spiral blued-steel balance spring with 6 3/4 turns pinned to a stud on the underside of the balance cock.
Temperature compensation: A Breguet type bimetallic compensation curb, screwed to the underside of the regulator index has one curb pin at its free end. The other curb pin is fixed in the underside of the index.
Means of Regulation: A polished steel index on the balance cock registers against a scale with 'A' and 'R' engraved on the balance cock table.
Train counts and beat Rate:
Great wheel 58 (fusee)
Centre wheel 86 Pinion 12
Third wheel 64 Pinion 8
Fourth wheel 60 Pinion 8
Escape wheel 28 Pinion 8
Beat Rate: 18,060
Motion Work: Cannon pinion 12
minute wheel 36, minute pinion 10
hour wheel 40
Calendar mechanism: A secondary pinion of 16 on the hour wheel drives an intermediate calendar wheel of 32 teeth on which a pin is mounted, indexing a 31 point star wheel which carries the date hand. The star wheel jumper spring, mounted on the inside rim of the dial plate, has been repaired at the foot end.
Repeating work: A pendant operated quarter repeat mechanism winding a mainspring by chain drive and striking the hours with single blows and the quarters with double blows. The system utilises an all-or-nothing piece and a surprise piece.
The polished steel repeat work is mounted on the front plate of the movement within the recess of the dial plate, with the barrel arbor assembly and gear train mounted between the plates. The barrel arbor assembly consists of a great wheel, recessed on its upper face to house a steel ratchet wheel and click. The hour rack, a steel wheel with 12 ratchet teeth cut on only half the circumference, operating the hour hammer, is integral with the barrel arbor diameter and is pinned onto the barrel arbor.
The hour rack also acts as one end of the fixed barrel which is mounted on the underside of the back plate, the other end is provided by the back plate itself which has a turned recess under the barrel. The outer end of the mainspring extends out through a slot in the barrel to an external hooking on the barrel wall.
Mounted on the squared extension of the barrel arbor projecting through the front plate is a steel drum with a steel beak on top, retained by a pin. A fusee-type chain is riveted to the drum and wrapped around the grooved edge. It then passes around a grooved pulley to be anchored in the free end of the repeat rack lever. This lever pivots at one end and has a tail which projects towards the centre of the movement and passes under a steel guide piece.
As the pendant is depressed the repeat rack draws the winding chain from around the winding drum, winding the mainspring. Teeth on the hour rack are drawn past the hour hammer tail which is held out of the path of the teeth when at rest.
The number of blows to be struck for the hour and the number of hour rack teeth that pass the hammer tail is determined by a steel snail mounted on a brass star wheel. This star wheel is controlled by a jumper and spring and is turned by a stud on the underside of the surprise piece mounted under the quarter snail on the cannon pinion. The hour snail and star wheel are mounted on the underside of the all-or-nothing piece. This lever pivots at one end and is biased towards the cannon pinion by a spring mounted on its upper surface, acting against a stud projecting up from the front plate passing through a hole in the all-or-nothing-piece.
The quarter rack is double ended, with three ratchet shaped teeth cut at each end and a curved tail pointing towards the centre of the movement. Pivoting at the centre on a stud, it is held back against the influence of a spring when at rest by the tail of the all-or-nothing-piece. One set of teeth engage with a pallet of the quarter hammer and the other with a pallet linked to the hour hammer. The number of blows for the quarters and the number of quarter rack teeth allowed to pass the hammer pallets is controlled by the quarter snail.
As the pendant is depressed the tail of the repeat rack descends onto the step on the hour snail, when fully depressed the pressure of contact causes the all-or-nothing piece to pivot away from the centre against the influence of its spring until banking against the stud passing through it. This small movement releases the quarter rack to drop onto the quarter snail allowing, on release of the pendant, the mechanism to operate. If the pendant is only partially depressed the all-or-nothing piece will not operate. This allows either all the hours and quarters to be struck or nothing.
On release of the pendant the mainspring turning the great wheel, drives the train of wheels and causes the hour rack teeth to engage the hammer pallet and sound the hours. The chain is wound back onto the winding drum and the repeat rack is drawn away from the hour snail. The steel beak on the squared extension of the barrel arbor turning with the winding drum, engages with a pin on the quarter rack only when the hours have been struck, driving the rack teeth against the hammer tail pallets causing two blows to be sounded for every quarter passed the hour. On completion of the quarter striking the rack is driven by the beak against the curved body of the quarter hammer pallet, allowing the all-or-nothing-piece to spring back into the locking position.
The speed of striking is controlled by the depth of the fly pinion. The pinion pivot runs in an eccentric plug with a squared projection allowing for adjustment by a watch key. An indicator hand which is now missing would have registered against the scale with 'V' and 'L' engraved on the back plate.
The first quarter from the hour to the quarter past is not struck and to avoid an erroneous striking of the quarters at the hour changeover the surprise piece is brought into operation. Loosely mounted below the quarter snail on the cannon pinion, the surprise piece is a segment equal to the height of the fourth or zero quarter step of the quarter snail. The surprise piece can move forward or backwards, the travel restricted by a pin in the underside of the snail acting in a cut-out in the surprise piece. Mounted on the underside of the surprise piece, the circular stud engages the hour snail star wheel as the cannon pinion rotates. The surprise piece is held back against its pin during engagement but the following tooth of the star wheel, moving under the influence of the jumper and spring, flicks the stud causing the surprise piece to pop out from under the quarter snail extending the zero or first quarter.
Adjacent to each hammer is a lever pivoting on a central screw with one end resting on the hammer tail and the other end formed at right angles and occupying a cut-out in the plate edge. This face of each lever has a threaded hole allowing for an adjusting screw from the case band to move the lever tail into the path of the hammer tail in order to adjust the hammer blow on the gong or bell.
The conical chain pulley is now crudely retained on its stud by a pin projecting through the side of the dial plate. The fly pinion pivot is broken. The fifth wheel of the repeat train runs in a curious proud bush an extension of a blued-steel figure of eight shaped end plate set in the back plate.
Repeat barrel and mainspring:
Barrel: internal diameter 9.5 mm, height 1.5 mm.
Mainspring: height 1.28 mm. thickness o.18 mm.
Repeating train counts:
Great wheel 46 (barrel)
Second wheel 34 pinion 6
Third wheel 30 pinion 6
Fourth wheel 28 pinion 6
Fifth wheel 26 pinion 6
Fly pinion 8
Winding Mechanism: Key wound.
Movement: diameter 45.6 mm, height 18.0 mm, pillar height 3.5 mm.
Provenance: Formerly in the Ilbert Collection. Ilbert purchased this from President in June 1938.
(1) Jean-George Remond, Master Goldsmith of Geneva (1783). An example of his work c.1790 in collaboration with Jean-Louis Richter an enamellist and miniaturist (1766-1841), is a Snuff-box in the form of a shell in the collections of the Musée d'Horlogerie, Geneva. Catalogue and Guide, 1990. Cat.No. 25, with Illustration p.38.
(2) Antoine Tavan born 1742 in Aost, France, established himself in Geneva in 1763 where he died in 1839. In 1805 Tavan completed a series of model escapements, including one of his pin-wheel escapement, for Melly Frères. In 1806 this was reported at the Institut de France. The models are now in the Musee d'Horlogerie, in Geneva. Although Antoine Tavan utilised the pin-wheel lever escapement it is believed that it was first invented by Louis Amant in 1741, improved by Jean-Andre Lepaute and applied to a watch in detached lever form by Robert Robin. For further information on Tavan's lever escapements and the pin-wheel escapement see Paul Chamberlain, It's About Time, pp. 67-73. A drawing of a similar pin-wheel escapement but with the pins on one side of the wheel only and with the pallets one behind the other appears on page 72.
For further illustrations of pin-wheel escapements and a description see Adolphe Chapiro, La Montre Francaise pp. 293-297. For a watch by Bazile-Charles Le Roy with a similar escapement but with the pins on one side of the escape wheel only, see page 295, Fig. 596, with enlargements of the lever Fig. 597.
The lever in this example is of similar construction, with the pallets mounted on arms from bosses clamped together on the pallet arbor by a collar and squared nut. One pallet arm is box cranked. The difference is that the lever arm and fork appear to be made separately and the pins are mounted on one side of the escape wheel only. One pallet arm therefore is necessarily longer than the other.
(3) The dust-cap on this watch is of an unusual design, having more in common with 18th century verge watches than 19th century lever watches. The fact that the winding square is very long and that it protrudes beyond the level of the dust-cap suggests that this movement may well have been housed in a small clock case rather than in a watch. The fact that Remond was a goldsmith rather than a watchmaker might suggest that this movement was housed in a decorated gold and enamel box rather than a watch case.
(4) Although there appears to be draw on one pallet only this is possibly accidental following redressing of the pallet faces.
- Not on display
Latest: 3 (2017)
Hairline cracks on dial.
- Acquisition date
- Acquisition notes
- Following the successful acquisition of the celebrated Ilbert collection of clocks (1958,1006 collection), prints and other related materials made possible by the generous donation of funds by Gilbert Edgar CBE Ilbert's watches were then acquired using funds provided by Gilbert Edgar, public donations and government funds.
- Britain, Europe and Prehistory
- Registration number
- Additional IDs
Previous owner/ex-collection number: CAI.1137 (Ilbert Collection)
Previous owner/ex-collection number: P272 (Ilbert Ledger)