- Museum number
ALUMINIUM CASED LEVER SPLIT-SECONDS CHRONOGRAPH [CASE NOT ORIGINAL].
Lever escapement; split seconds chronograph on back.
Keyless winding and hand-set.
Front enamel dial for hours and minutes.
Rear enamel dial for chronograph.
Custom-made aluminium case retaining original gold pendant-button and chronograph-buttons and silver inner bezel and pendant-bow.
- Production date
Diameter: 53 millimetres (case)
Diameter: 42.10 millimetres (front dial)
Diameter: 45 millimetres (rear dial)
Thickness: 21.30 millimetres
- Curator's comments
- Comment from Richard Good, Catalogue of Watches in the British Museum. Vol. V (Unpublished manuscript)
Made by Nicole Nielsen & Company
London, c. 1895
Movement of a double dialled, ratchet tooth lever, split-seconds chronograph in a later case.
Signature: On both dials 'NICOLE NIELSEN & CO. 14 SOHO SQ RE LONDON'.
Case: A later custom-made aluminium case, glazed back and front. The silver pendant bow with a quality mark, the gold button held by a screw on the pendant arbor. The fact that the pendant is mounted at the III o'clock position suggests that the original case was of hunter type.
Dial & Hands: Flat canister dials. 'Nicole Nielsen' inscribed on the back of both dials. The front dial has a sunk subsidiary seconds dial left of centre and a sunk circular section with the name to the right. This dial also has in the counter-enamel in red 'Centre Sec? Seconds'? with another u-deciphered inscription. The outside of this dial is marked in 1/5th seconds with Arabic numerals every five seconds. The split seconds hands, one brass, one blued-steel, register on this dial. A small sector regulation indicator inscribed 'FAST' and SLOW' is positioned at the 30 second mark. The hand that registers on this dial is mounted on an arbor carrying a cam on which the index tail rests.
The rear dial is the time of day dial, with spade-pattern hands of blued steel. It would seem that this was once a canister dial which located on the case not the movement. The canister edge has been removed and the dial now just rests in a recess in a bezel with nothing to locate it.
Dial-plate: None intended.
Dust-cap: None intended.
Ebauche Marks: 8651 and 8519 on the front plate under the dial.
Frame: An unusual three-quarter plate construction with the split seconds dial on the substantial front plate. This is recessed for the going train and has a circular bridge carrying the escapement bearings. The back plate is on the time of day dial side and is also recessed for the going train. There is no evidence to show how the movement was originally held in the case, except for a single peg set in the edge of the main plate, and a steel bridge for the inclined transmission winding wheel. The second wheel is offset. The balance cock is engraved with foliate scrolls.
Barrel and Mainspring.
Barrel: going barrel with four-turn Geneva stop work. Internal diameter 17.0 mm. height 3.00 mm.
Mainspring: height 2.5 mm, thickness 0.21 mm.
Barrel Arbor: diameter 5.5 mm, snailed.
Train: gilded wheels, except for the great wheel, all the wheels have five crossings.
Jewelling: Jewelled bearings for the third wheel onwards, the pivots in bombé jewels. The escapement with ruby endstones. Also the central chronograph pivot holes are jewelled.
Escapement: An acute-angle layout ratchet tooth lever escapement with short lever, double roller and triangular impulse pin. The enclosed pallet stones have convex impulse and locking faces. A beautifully made steel dart on the lever and an exceptionally delicate polished-brass escape wheel.
An equal impulse escapement.
No. of teeth embraced 32.
Balance & Spring: A split bimetallic balance, the two arms of sage leaf pattern, the compensation and quarter screws of gold. Balance diameter 20.3 mm thickness 0.85 mm. A blued-steel flat spiral spring of 182 tight turns and with a terminal curve attached to a polished steel stud on the balance cock.
Means of Regulation: An index with a double tail end is free to move on a boss on the balance cock. A light spring holds one of the tail ends against an irregular shaped cam. An arbor pivoted in the front plate carries the cam on one end and the stout indicator on the other for adjusting the rate. The dial has a sector shaped divided scale inscribed 'FAST' and 'SLOW'. Moving the stout blued-steel hand on the dial rotates the cam which then moves the index to adjust the rate.
Train Counts and Beat Rate:
Great wheel 76 (Barrel)
Centre wheel 80 pinion 10
Third wheel 75 pinion 10
Fourth wheel 80 pinion 10
Escape wheel 15 pinion 8
Beat rate: 18,000
Motion work: Cannon wheel 70,
minute wheel 70, minute pinion 7
hour wheel 84.
Keyless work: The barrel arbor has an extended square which carries a ratchet wheel on the outside of the back plate. The ratchet and its spring are recessed in to the back plate beside the ratchet wheel. Another steel wheel having spur teeth is pivoted on top of the ratchet wheel on a steel plate held by two screws passing into the ratchet wheel. On the underside of the steel wheel is a ratchet and click, the ratchet meshing with the teeth of the lower ratchet wheel. The spur wheel is in mesh with a bevel wheel mounted on a plate at the pendant and inclined at an angle so that its teeth can also mesh with another bevel wheel on the end of the winding arbor. On turning the winding arbor to wind, all four wheels turn and the spring is wound. On reversing the direction of wind the winding ratchet wheel does not turn, but the other three wheels do.(1)
Hand setting: Beside the spur wheel and concentric with the winding ratchet wheel another smaller spur wheel is planted, in constant mesh with the former. The latter wheel is pivoted on a shoulder screw on a steel arm, itself pivoted and with a return spring on the underside of the back plate. A push-piece beside the pendant, in the band of the case, connects with the steel arm. If pressure is applied to the push-piece the steel arm pivots until it reaches a stop, the steel wheel carried on it is then in mesh with another similar wheel under the minute wheel. On turning the winding button the hands can be set. Since all the winding work turns at the same time, the hands must be set before the mainspring is fully wound, or they can only be set one way.(1)
Chronograph mechanism: One push-piece in the band of the case operates the start, stop and return to zero of the upper chronograph hand. The lower chronograph hand normally follows exactly beneath the upper unless the split seconds mechanism is in operation.
The chronograph mechanism is controlled by a star wheel and jumper, and a pillar wheel. Motion is transmitted to the central fine-tooth brass chronograph wheel by a pinion on the upper end of its arbor. This arbor is pivoted in the main plate, and in a steel arm so that it can rock and cause the steel wheel to move in and out of mesh with the brass wheel. There is a brake lever, and a return to zero lever working with a heart-shaped cam on the chronograph wheel arbor, as in a modern chronograph mechanism of this type. The sequence of operations can be summarised as in the table, starting with the chronograph hand at zero.
Split-seconds mechanism: Closely resembling a modern mechanism of this type. Another star wheel controlled by a jumper is operated by the other push-piece in the band of the case near that for the chronograph. It causes two arms to hold or release a light steel wheel pivoting on the chronograph hand arbor and with a short cannon for the split-seconds hand. On the underside of this wheel is a lever and light spring operating on a heart-shaped cam fixed to the chronograph hand arbor. When the wheel is free, with the chronograph mechanism running, the two hands move together. If the split-seconds push-piece is operated, the wheel is held up and the split-seconds hand stops. A second pressure on the same push-piece causes the hand to catch up, because the lever on the underside of the wheel moves to the smallest radius on the heart-shaped cam, under the influence of its spring. This causes the wheel and hand to turn, until the hand catches up and coincides with the chronograph hand.
There is no means of recording intervals of time of more than one minute's duration. The two push pieces are the originals and are in gold.
Case: Diameter 52.8 mm. height 21.3 mm (over glasses).
movement: diameter 45.3 mm, height 13.0 mm, frame height 6.3 mm.
Provenance: Formerly in the Ilbert Collection. Purchased by Ilbert from Malcolm Gardner in 1938.
(1) Adolphe Nicole patented a type of fusee keyless work (No. 10,348 in 1844) and this patent included a chronograph with heart-shaped cam. In 1862 he patented an improved chronograph with a pillar wheel control (No. 1,461).
This watch follows Swiss practice in many respects.
For full details of the firm of Nicole Nielsen see Mercer, 'The Frodshams', pp.198-205.
- Not on display
- Latest: 3 (2017) not seen inside
- 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.1122 (Ilbert Collection)
Previous owner/ex-collection number: P247 (Ilbert Ledger)