- Museum number
MOVEMENT AND DIAL OF A HALF-HUNTER LEVER WATCH.
3/4-plate; fusee; Harrison's maintaining power.
Savage two-pin lever escapement; split bi-metallic balance; free-sprung spiral balance-spring.
White enamel dial; hours I-XII; sunk subsidiary seconds.
Gold double-swell spade hour and minute hands; blued steel seconds hand.
Half-hunter case missing.
- Production date
Diameter: 40.80 millimetres (back-plate)
Diameter: 46 millimetres (dial)
Thickness: 11.50 millimetres
- Curator's comments
- Comment from Richard Good, Catalogue of Watches in the British Museum. Vol. V (Unpublished manuscript)
Made by John Hutton
London, c. 1860
Movement of a ratchet tooth lever watch with Savage two-pin fork and roller action.
Signature: 'HUTTON'S PATENT LEVER CHRONOMETER LONDON 954' on the dial.(1) 'John Hutton, 10, Mark Lane, LONDON No 954' on the back plate.
Case: The half-hunter case is now missing. The movement was hinged to the case at XII.
Dial & Hands: High quality flat dial with sunk subsidiary seconds dial. A letter 'J' fired into the counter-enamel. Gold spade pattern hands, the hour hand double swell for half hunter display. A blued-steel seconds hand.
Dial-plate: No dial-plate intended, the dial pinned directly to the front plate.
Dust-cap: None intended.
Ebauche Marks: A & G 18 2
Frame: Half-plate layout, the back plate supported by three turned pillars and retained by screws. A separate bridge for the fusee pivot in the front plate and another long bridge on the front plate which carries the third, fourth and escapement bearings. Separate cocks for the fourth wheel and also one for the pallets and escape wheel. The balance cock is engraved all over with fine foliate scrolls.
Fusee, Barrel and Mainspring:
Fusee: five-turn fusee with Harrison's maintaining power and a steel maintaining ratchet wheel.
Barrel: flanged, internal diameter 16.4 mm, height 3.3 mm.
Mainspring: height 3.0 mm, thickness 0.21 mm.
Barrel Arbor: diameter 5.6 mm, not snailed.
Hooking: originally square but now round.
Train: A high quality gilded brass train of chronometer standard with high-count pinions. The centre, third and fourth wheels have five crossings.
Jewelling: Jewelled bearings from the fourth wheel onwards, including the pallet pivots, with a diamond endstone in the balance cock and a ruby endstone in the front plate. All the jewels are rubbed in except for those for the balance which are in screwed settings.
Escapement: A high quality acute-angle layout Savage escapement incorporating a combined unlocking and impulse stone.(2) Steel pallet frame and gold lever with a gold impulse pin. The wedge shaped gold impulse pin is set in a gold post which is in turn set into the gold lever. The pallet stones are convex on the locking and impulse faces. The polished brass escape wheel has three crossings. There is draw in the escapement.
An equal impulse escapement.
Number of teeth embraced 32.
Balance & Spring: A split bimetallic balance with gold compensation screws and quarter timing nuts. Balance diameter 18.3 mm, thickness 1.6 mm. Flat spiral blued-steel spring of 16 turns with a terminal curve. A steel rectangular collet on the balance staff and a steel stud fixed to the balance cock.
Means of Regulation: Free sprung, therefore the timing nuts on the balance must be used for regulation.
Train Counts and Beat Rate:
Great wheel 72 (fusee)
Centre wheel 80 pinion 12
Third wheel 75 pinion 10
Fourth wheel 70 pinion 10
Escape wheel 15 pinion 8
Beat Rate: 15,750
Motion work: cannon pinion 14
minute wheel 42, minute pinion 12
hour wheel 48
Winding System: Key wound.
Movement: diameter 46.0 mm, height 11.4 mm, pillar height mm.
Provenance: Formerly in the Ilbert Collection. Ilbert purchased this from Collet, 4 July 1932.
(1) Patent no. 11427 was granted to John Hutton on October 22nd 1846 and was number 11427. Clause 4 states:-
'An improvement in the 'two pin lever escapement'. This consists in inserting a solid piece of ruby or other hard stone in the roller and in placing the impulse notch in this ruby and forming the lower part of the ruby so as to receive the fork of the lever.
(2) Probably one of the highest quality Savage two-pin escapement watches ever to be made, but see also Cat. no. 235 (registration no. 1958,1201.1034) watch by Edwin Langford. This watch has all of its components of chronometer standard. The inclusion of a ruby impulse notch and a gold lever is especially impressive.
Bibliography: Richard Good, 'The Savage Two Pin Lever Escapement' HJ, Vol. 135, No. 12 (June 1993) p. 412.
- Not on display
Latest: 2 (2017)
- 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.1021 (Ilbert Collection)
Previous owner/ex-collection number: N74 (Ilbert Ledger)