- Museum number
SILVER-CASED SUBSIDIARY SECONDS POCKET-CHRONOMETER WITH SPRING DETENT ESCAPEMENT.
Chronometer watch; contemporary fake.
Spring detent escapement.
- Production date
- 1811-1815 (?)
Diameter: 61 millimetres (case)
Diameter: 52.90 millimetres (dial)
Thickness: 26.20 millimetres
- Curator's comments
- Comment from Anthony G. Randall and Richard Good, Catalogue of Watches in the British Museum. Vol. VI (1990)
Signed Ellicott but Maker Unknown, 1815
Signature: On the back plate 'Ellicott'. On the barrel bridge 'Royal Exchange LONDON 1021.'(1)
Case: Open face silver case with the London hallmark for 1815 and the maker's mark I.M. Pendant marker's mark IF. The glazed bezel and back shutting flush, the middle remaining as a narrow rim. Case lock spring operated by a push-piece in the flattened pendant, and with a fly spring to open the back. Diam. 60.75 mm, h. over glass 25.8 mm.
Dial and hands: Flat enamel dial, slightly cracked, with 'seconds' fired in red on the back, subsidiary seconds. The dial fixed to the dial plate by three short feet and pins. The signature not repeated on the dial.
Gold minute and hour hands not matching in colour, the steel seconds hand a replacement.
Dial plate diam. 53.0 mm; front plate diam. 49.0 mm; back plate diam. 45.3 mm; frame h. 8.1 mm.
Frame: Similar to registration no. 1958,1201.1596 but without dust ring or cover; the gilding pale. Note the dust tube and foot for the winding arbor.
Fusee: Similar to 1958,1201.1596, no return spring for the setting-up pawl on the barrel bridge. The maintaining ratchet wheel steel. The mainspring barrel without a flange at the cover end.
Going train: Similar to 1958,1201.1596, but the gilding pale.
Jewelling: Similar to registration no. 1858,1201.2091.
Escapement: Earnshaw type of detent escapement, the brass escape wheel similar to an English ratchet-tooth lever escape wheel, not sunk, presumably a replacement. The jewelled discharge roller mounted between the impulse roller and the balance. The impulse roller left grey, once jewelled with an impulse pallet leaning towards a radial from the roller centre to the tip. The impulse jewel replaced by a piece of polished steel.
The replacement detent in a slot similar to an Arnold escapement. Banking is provided by an eccentric plate and screw. The locking stone replaced by a half-round piece of steel.
Balance: Bimetallic two-armed balance with brass segment compensation weights and screws set in the rims at the ends of the arms. Diam. of rim 20.9 mm, h. 1.93 mm.
Balance spring: Blued steel helical spring of 7½ turns, and with terminal curves, free sprung to an adjustable overhanging stud. Brass collet on the balance staff.
Going train counts:
Great wheel (fusee) 60 teeth
Centre pinion 12 leaves, wheel 80 teeth, no crossings
Third pinion 10 leaves, wheel 75 teeth, 6 arms
Fourth pinion 10 leaves, wheel 80 teeth, 6 arms
Escape pinion 8 leaves, wheel 15 teeth, 3 arms
Beats per hour: 18,000
Cannon pinion 12 leaves, minute pinion 14 leaves
Hour wheel 42 teeth, minute wheel 48 teeth, both snailed
Provenance: Ilbert Collection; Ilbert purchased this watch from Hutchinson in 1935.
(1) This watch is undoubtedly a fake with spurious signatures put on after gilding and the numbers not fitting Ellicott's series.
- Not on display
- Latest: 3 (2017)
- Acquisition date
- Britain, Europe and Prehistory
- Registration number
- Additional IDs
Previous owner/ex-collection number: CAI.1735 (Ilbert Collection)
Previous owner/ex-collection number: P3 (Ilbert Ledger)