- Museum number
SILVER-CASED EIGHT-DAY LEVER WATCH WITH UP-AND-DOWN INDICATOR.
Full-plate construction with a separate barrel bridge. Circular gilt-brass
plates with four turned pillars retained by screws. Barrel with ratchet and click set-up mounted under the dial. Fusee with chain and standard stop-work. Harrison's maintaining power. Four wheel train, the second wheel and third pinion recessed into the front-plate. The off-set second wheel drives the motion work. There is no centre wheel. Ratchet-tooth lever escapement with gold 3-arm balance and spiral balance spring with an index on the balance cock.
Seconds hand rotates once in two minutes. Escape wheel has 18 teeth [see patent]. Slow-beating balance and six turns on the fusee.
DIAL & HANDS
Cream enamel dial with sunk subsidiary seconds 20-120 and sunk up-and-down down dial 0-8. Chapter-ring with minute circle and Roman hours I-XII. Gold fleur-de-lys hour and minute hands, blued steel subsidiary hands.
Silver consular case with engine-turned decoration around the case-band. In the middle of the back an oval garter and shield decoration. Case with casemaker's mark, hallmarks, pendant-maker's mark and number.
Gilt-brass dust-cap with steel slide.
- Production date
Diameter: 58.70 millimetres (case)
Diameter: 49.70 millimetres (movement)
Thickness: 20 millimetres (case)
- Curator's comments
Patent Nov. 26th 1884, no.15,554. see Abridgements 1884-96 p.14. Illustrated.
The patent covers the 8-day train.
Comment from Richard Good, Catalogue of Watches in the British Museum. Vol. V (Unpublished manuscript)
Made by John Robinson
Blackburn, England. 1893
Silver cased eight-day ratchet tooth lever watch
Signature: On the dial '8 DAY WATCH PATENTED BY JOHN ROBINSON BLACKBURN',(1) on the back plate 'John Robinson 1853', and on the barrel bridge '15,, PENNY,, STREET BLACKBURN'.
Case: Heavy silver, open face, consular case with a milled band and the back centred with a blank shield and garter. The case is hallmarked Chester 1893 and bears the casemaker's mark R.J.P(2) and the numbers 2 and 1854 (note the numbers on case and movement do not agree). The silver pendant is hallmarked either Chester 1882 or Birmingham 1893 and is punched with the pendant maker's mark C.H in cameo.(3) The silver bow is punched with a quality mark.
Dial & Hands: A flat dial with sunk centre and two sunk subsidiary dials, for seconds and up-and-down indication. The seconds dial is calibrated 20, 40, 60, 80, 100, and 120, and the up-and-down dial is inscribed 'UP 0 1 2 3 4 5 6 7 8 DOWN'. Fired into the counter-enamel in black is the number '1'. Gold fleur-de-lys hour and minute hands. Blued-steel seconds and up-and-down hands.
Dial-plate: None intended.
Dust-cap: Standard pattern without marks.
Ebauche Marks: none
Frame: A conventional full plate layout, the back plate supported by four turned pillars and secured by screws, three with domed heads. The fusee bearing in the back plate bushed, the bush being crudely secured with soft solder. Gilded potence with straight moulded foot. The balance cock is engraved with foliate scrolls and a lozenge pattern.
Fusee, Barrel and Mainspring:
Fusee: six-turn fusee with Harrison's maintaining power with a steel maintaining ratchet wheel.
Barrel: flanged, internal diameter 18.2 mm, height 4.6 mm. Mainspring: height 4.4 mm, thickness 0.26 mm, now broken.
Barrel Arbor: diameter 6.3 mm, snailed.
Train: Brass wheels not gilded, the second, third and fourth wheels with five crossings. The great wheel revolves once in 32 hours, which with 6 turns of the fusee gives a running time of 8 days.
Jewelling: Jewelled bearings for the balance pivots only, with ruby endstones, the potence endstone is mounted in a wedge.(4)
Escapement: An acute-angle layout ratchet tooth lever escapement with short lever, single roller and D-shaped impulse pin. The enclosed pallet stones have convex impulse and locking faces. The brass escape wheel has three crossings.
A mixed impulse escapement
No. of teeth embraced 42
Balance & Spring: A plain gold, three arm balance with a groove machined in the upper surface of the rim. Balance diameter 21.4 mm, thickness 0.5 mm. Blued-steel flat spiral spring with 132 turns pinned to a polished steel stud screwed to the back plate.
Means of Regulation: An index on the balance cock registers against a divided scale with 'FAST' and 'SLOW' engraved on the balance cock table.
Train Counts and Beat Rate:
Great wheel 80 (fusee)
Second wheel 72 pinion 10 (revolves once in 4 hours).
Third wheel 60 pinion 6
Fourth wheel 60 pinion 6 (revolves once in 2 minutes)
Escape wheel 18 pinion 6
Beat rate 10,800.
Motion work: cannon pinion 14,
minute wheel 56, minute pinion 12,
hour wheel 36, intermediate 56.
The second wheel arbor is hollow with a friction-tight central pin, squared at the back for hand setting and with the intermediate motion-work wheel mounted at the front. This wheel meshes with minute wheel and pinion which in turn drive the cannon pinion and the hour wheel respectively, both of which run freely on a central stud on the front plate. There is no provision for taking up any backlash in the system.
Up-and-down work: the pinion on the fusee arbor 10,
up-and-down wheel 75.
Winding System: Key wound
Case: diameter 58.7 mm, thickness 20.1 mmm (over the glass)
Movement: diameter 49.7 mm, height 15.3 mm, pillar height 4.4 mm.
Provenance: Formerly in the Ilbert collection. Ilbert purchased this in Edinburgh in 1930.
(1) Patent no. 15,544 was granted to J. Robinson 26th November 1884. It reads as follows:-
'Going trains for watches arranged to go for a number of days. A longer mainspring is used, and the fusee has two more turns on it in order to hold a longer chain. The figure shows the dial work. A wheel is mounted on the arbor A of the second wheel of the train, and gears with the intermediate wheel on B. This intermediate wheel and its pinion drive the cannon pinion and hour wheel on a fixed central pin C, and so actuate the hands. The train is arranged so that the seconds hand on the fourth wheel arbor makes one revolution in two minutes. A pinion E on the fusee arbor drives a wheel on the arbor F which carries an indicator showing for what period the watch is wound up.'
It should be noted, therefore, that this watch is not exactly as stated in the patent in that the intermediate wheel meshes with the minute wheel and not the cannon pinion.
(2) The mark of Robert John Pike, watchcase maker of Cromwell Street, Earlsdon, Coventry, see Priestley pp.169 and 183, where he is noted as having registered his mark both at the Birmingham and Chester assay offices.
(3) It is not possible to positively identify this mark but it might be that of Charles Harris who also registered his mark in both Chester and Birmingham, see Priestley, pp.160 & 189.
(4) A very late example of this method.
- Not on display
- Latest: 3 (2017)
- Acquisition date
- Britain, Europe and Prehistory
- Registration number
- Additional IDs
Previous owner/ex-collection number: CAI.1088 (Ilbert Collection)
Previous owner/ex-collection number: F1 (Ilbert Ledger)