- Museum number
BLUED STEEL CASED LEVER WATCH WITH DIGITAL HOURS.
Half-plate; going barrel.
Pin-pallet lever escapement; rocking-bar keyless for hand-set.
White enamel dial; minutes 0-60; hours 1-12 and 13-24 in two apertures.
Gilt minute hand.
Blued steel case with glazed inner dome (glass missing).
Diameter: 53.30 millimetres (case)
Diameter: 43.50 millimetres (dial)
Thickness: 18.40 millimetres
- Curator's comments
- Comment from Richard Good, Catalogue of Watches in the British Museum. Vol. V (Unpublished manuscript)
Switzerland, c. 1900
Watch with jumping hours and a pin pallet lever escapement.
Case: An open face gun metal case with inside the back a second glazed bezel, the glass now missing. Stamped inside the back is 'ACIER GARANTI'.
Dial and Hands: A domed enamel dial with two apertures, one for the hours 1-12 at 12 o'clock, one for the hours 13 to 24 at 6 o'clock. Beneath the enamel dial is the aluminium hour dial marked in black Arabic numerals on the inside circle 1-12 and on the outer circle 13-24. On the back of this dial is a ratchet toothed wheel with 12 teeth. A central minute hand of gilt brass. Heavy minute marks in black, numbered at every 5.
Ebauche Marks: Stamped on the back plate is 'BREVETTE' and the Helvetia cross. This is probably a Reconvilier movement who specialised in Roskopf type watches.
The back plate is supported by three turned pillars and secured by screws. The balance and escapement are mounted on a sub plate which is split so that with the aid of a screw the depth between the escape wheel and the pallets can be altered. The plates are of a heavier gauge than is normal with a Roskopf type movement. There are cocks for the escape wheel the lever and the balance. There is a bridge to hold down the barrel ratchet and the end of the click. All of the parts visible from the back are frosted and gilded.
Barrel and Mainspring: The going barrel with the minute wheel mounted on the barrel cover.
Barrel inside diameter 21.8 mm., inside height 3.0 mm.
Mainspring height 2.4 mm., thickness 0.21 mm.
Arbor: Diameter 5.8 mm., snailed.
Hooking: The mainsrping is hooked to a turn of heavier spring which can slip from notch to notch, of which there are four in the barrel wall. This provides a slipping mainspring.
Train: The brass wheels with five crossings, the steel escape wheel with four.
Jewelled: At the escapement, the jewels rubbed in. A ruby endstone in the balance cock but a steel endplate in the front plate.
Escapement: A pin pallet lever escapement, obtuse angle layout, a long lever, effectively a double roller with a brass impulse finger. The lever of steel with steel pins.
An equal impulse escapement.
Number of teeth embraced 3 ½.
Balance and Spring: A three armed gold balance with a rounded rim. Balance diameter 16.1 mm., thickness 0.7 mm.
The flat spiral blued-steel spring with 11¾ turns.
Means of Regulation: An index on the balance cock with a divided scale and 'AVANCE RETARD' engraved on the cock.
Train Counts and Beat Rate:
Great wheel (barrel) 128 (Rotates in four hours)
Centre wheel 84 pinion 8
Third wheel 60 pinion 7
Escape wheel 18 pinion 6
Beat Rate: 17,280
Motion Work: Cannon pinion 18, minute wheel 72, Another pinion of 18 is driven by the minute wheel. This pinion has a squared boss which carries a finger which indexes the hour disc. These two components are held by a shoulder screw.
Winding system: Side set positive keyless work.
Dimensions: Case diameter 53.3 mm., height 18.2 over the glass.
Movement diameter 44.0 mm., height 13.5 mm.
Provenance: Formerly in the Ilbert collection.
- Not on display
- Latest: 3 (2017)
- Acquisition date
- Britain, Europe and Prehistory
- Registration number
- Additional IDs
Previous owner/ex-collection number: CAI.1092 (Ilbert Collection)
Previous owner/ex-collection number: N45 (Ilbert Ledger)