- Museum number
SILVER-CASED SUBSIDIARY SECONDS POCKET-CHRONOMETER WITH SPRING DETENT ESCAPEMENT.
Spring detent escapement.
Later silver case.
- Production date
- 1858 (case)
Diameter: 59.30 millimetres (case)
Diameter: 52 millimetres (dial)
Thickness: 24.80 millimetres
- Curator's comments
- Comment from Anthony G. Randall and Richard Good, Catalogue of Watches in the British Museum. Vol. VI (1990)
Made by Anthony Mesure, c. 1820.(1)
Signature: On the back plate 'Anthy Mesure London No 1043'.
Case: Later open face silver case with a fixed dome, the glazed bezel and back both hinged to the middle. The back opening by a push-piece and case catch at the pendant and a single fly spring acting on the back joint. Floral engraved decoration round the winding hole in the dome. The middle and back decorated with engine turning, and a shield in the centre of the back. London hallmark possibly for 1861 and casemaker's mark J.K., and the number 1043 repeated inside the dome and back, and the watch number and hallmark also on the bow and pendant. Diam. 59.0 mm, overall h. 24.8 mm.
Dial and hands: Flat enamel dial inscribed CHRONOMETER(2) in top half and with subsidiary seconds, attached to the dial plate by three feet and pins.
Blued steel minute and hour hands, the seconds hand missing.
Dial plate diam. 53.4 mm; front plate diam. 51.4 mm; back plate diam 47.7 mm; frame h. 8.4 mm.
Frame: Full plate construction with four turned pillars, the back plate retained by pins. The balance potence foot set towards the centre of the back plate instead of towards the edge beside the barrel. A dust ring once retained by two dog screws on the edge of the back plate, now missing. The dial plate attached to the front plate by three feet and pins, and carrying the new movement hinge partly filed away to fit into the replacement case. The dial plate scratched '3 and 5 William Goswell London cased July 1861'. The new case catch and spring fitted on the front plate under the dial. The brass parts gilded. One empty rectangular hole of unknown purpose on the edge of the front plate near the case catch.
Fusee: Key wind fusee with the usual stop-work and maintaining power, the maintaining ratchet wheel brass. Setting-up-work on the front plate under the dial, in a shallow recess, the barrel arbor with an extended square on that end only. The barrel flanged on the cover end. The maintaining power detent does not belong to this watch and has been bent and filed to fit.
Going train: Remarkably crudely made and badly finished, only the pinions and pivots polished. The brass wheels not gilded.
Jewelling: The pivots of the third, fourth and escapement in pierced jewels with screwed settings, those of the escapement with endstones. A diamond endstone in a wide white steel setting on the balance cock.
Escapement: The remains of a detent escapement of Earnshaw type. The wrecked brass escape wheel with rim and arms sunk below the level of the teeth. The detent foot only remaining, screwed to the underside of the back plate beside a banking piece carrying a banking screw, which is also screwed to the underside of the back plate. Solid steel impulse roller, the edge, bottom and large radial impulse notch once polished. The discharge jewel set in a wedge-shaped roller below the impulse roller.
Balance: Bimetallic two-armed balance, not original, with brass segment weights held with steel plates and screws from the top. Timing screws set in the rims at the ends of the arms. Diam. 21.0 mm, h. 2.0 mm.
Balance spring: Blued steel flat spiral spring of 10 turns, without overcoil or terminal curves, free sprung to a brass stud on the balance cock. Round brass collet on the balance staff.
Balance cock: Of unusual shape and set slightly inside the edge of the back plate. The upper surfaces decorated with engraving of acanthus leaf, dog tooth, a basket of flowers and other motifs.
Great wheel (fusee) 72 teeth
Centre pinion 12 leaves, wheel 80 teeth, no crossings
Third pinion 8 leaves, wheel 48 teeth, 5 arms
Fourth pinion 8 leaves, wheel 60 teeth, 5 arms
Escape pinion 7 leaves, wheel 15 teeth, 4 arms
Beats per hour: 15,428 f
Cannon pinion 12 leaves, brass minute pinion 14 leaves
Hour wheel 42 teeth, minute wheel 48 teeth
Minute wheel and pinion probably not original.
(1) Baillie 1951 lists Anthony Mesure at 8 Craven Building, Drury Lane, London, in 1810 and at 420 Strand, 1814-23.
(2) The cheap construction, poor finish and technical primitiveness of this watch suggest that it might well be a early example of an attempt to deceive or take advantage of the esteem merited by the title chronometer, which is marked on the dial.
Provenance: Ilbert Collection.
- Not on display
Latest: 5 (2017) lots of verdigris
5 (Oct 1995) Seconds hand missing. Spring detent broken, foot remains. Banking screw block damaged.
- 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.1729 (Ilbert Collection)
Previous owner/ex-collection number: H76 (Ilbert Ledger)