- Museum number
Minute-repeating chronometer with whiplash regulator.
- Production date
Diameter: 44.70 millimetres (dial)
Thickness: 15.20 millimetres
- Curator's comments
- Comment from Richard Good, Catalogue of Watches in the British Museum. Vol. V (Unpublished manuscript)
Switzerland, c. 1900
Watch movement with minute repeating and chronograph and with a club tooth lever escapement.
Signature: No signature but on the barrel bridge, in a Helvetia cross is 3919
Case: Missing, but was a hunter case.
Dial and Hands: Flat canister dial with a fifth seconds circle around the minute circle, numbered at each 25 fifths of a second. Sunk subsidiary seconds dial. Blued-steel spade hands and centre seconds hand, the subsidiary seconds hand missing.
Ebauche Marks: 32585, a small 2 and a broad sword or dagger.
Frame: Bar layout, the cocks and bridges numbered 38, although it is not clear why. The repeating train housed beneath the combined barrel and centre bridge so with all the disadvantages of a full plate design.
Barrel and Mainspring:
Going barrel Internal diameter 16.4 mm., height 2.6 mm
Mainspring height 2.4 mm., thickness 0.21 mm
Arbor: diameter 5.4 mm., snailed
Train: Brass wheels gilded with five crossings except for the escape which has four.
Jewelled: from the third onwards for the pivots in the back plate and from the fourth onwards, for those in the front plate. Additionally a jewel for the back pivot of the centre seconds pinion. Jewels rubbed in, ruby endstones to the balance.
Escapement: Club tooth lever, straight line layout, short lever, double roller, impulse pin elliptical in section. Pallet stones covered and convex on locking and impulse faces. Escape wheel of brass, teeth not chamfered. Pallet frame with poising tails.
An equal impulse escapement.
Number of teeth embraced 3½.
Balance and Spring: A split bimetallic balance diameter 15.8 mm., thickness 1.0 mm. Blued-steel flat spiral spring with 17 turns and a terminal curve.
Means of Regulation: Micrometer controlled index on the balance cock, the screw controlling it is missing, the index registering against a divided scale with engraved 'FAST SLOW'.
Train Counts and Beat Rate:
Great Wheel (barrel) 60
Centre wheel 80 pinion 10
Third wheel 75 pinion 10
Fourth wheel 70 pinion 10
Escape wheel 15 pinion 7
Motion work: cannon pinion 14
Minute wheel 28, minute pinion 10
hour wheel 60
Keyless work: Side lever set positive keyless work.
Repeating work: of the inexpensive variety. see Appendix 0-0. A tic-tac escapement type of speed control for the repeater train. There is no all-or-nothing device and the flirt control arm is in continuous contact.
Chronograph work: Conventional castle wheel control, the indexing of this would have been by means of a plunger in the case situated at 12 o'clock.
Dimensions: Movement diameter 44.0 mm., height 14.2 mm
Provenance: Formerly in the Ilbert collection. Ilbert purchased this in the Caledonian market 7/4/1933.
- Not on display
Latest: 3 (2017)
2 (Feb 1995)
- 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.1259 (Ilbert Collection)
Previous owner/ex-collection number: N26 (Ilbert Ledger)