- Museum number
MOVEMENT AND DIAL OF AN EIGHT-DAY LEVER WATCH.
Twin going-barrels driving a common centre pinion.
Ratchet-tooth lever escapement; helical duo-in-uno free-spring; keyless winding and hand-set.
White enamel dial; sunk subsidiary seconds.
Blued steel spade hands.
Diameter: 44.80 millimetres (back-plate)
Diameter: 50.50 millimetres (dial)
Thickness: 11 millimetres
- Curator's comments
- Comment from Richard Good, Catalogue of Watches in the British Museum. Vol. V (Unpublished manuscript)
Made by Charles Frodsham & Company
Movement of an eight-day ratchet tooth lever watch with twin going barrels
Signature: On the dial 'CHAs FRODSHAM 84 STRAND. LONDON 06398 AD.Fmsz'. On the back plate 'Chas Frodsham, 84, Strand, LONDON. No. 06398. AD..Fmsz'.
Case: Missing. The movement was held in the case by a locating peg and a single dog screw.
Dial and Hands: A flat canister dial with a silver rim. A sunk subsidiary seconds dial. The minutes numbered at every five. Blued-steel spade pattern hour and minute hands. The blued-steel seconds hand is not original.
Dial-Plate: None intended.
Dust-Cap: None intended.
Ebauche Marks: None
Frame: Three quarter plate layout, the back plate supported by four turned pillars and secured by screws. A combined escape wheel and pallet cock. A plain balance cock. Two cocks support the barrel arbor pivots on the dial side of the front plate.
Barrels and Mainsprings:
Barrels: both barrels have four-turn Geneva stop work. Both barrels of equal size, internal diameter 19.0 mm, height 3.24 mm.
Mainsprings: height 3.2 mm, thickness 0.23 mm. Both mainsprings of equal size.
Barrel Arbors: diameter 6.4 mm, not snailed. Both barrel arbors of equal size.
Train: All the wheels gilded, intermediate, centre, third and fourth wheels with six crossings. A high quality train. The twin great wheels drive a common intermediate pinion. The extended fourth wheel arbor for the seconds hand is badly bent.
Jewelling: Jewelled bearings in the front plate from the third wheel onwards. In the back plate all the pivots run in jewelled holes. All the jewels are in screwed settings except for the third jewel in the front plate which is rubbed in. The escapement with ruby endstones throughout.
Escapement: An acute-angle ratchet tooth lever escapement with short lever, double roller and D-shaped impulse pin. The lever has a forked end with virtually no horns and there is a gold dart screwed and steady pinned to it. The enclosed pallet stones have convex impulse and locking faces. The polished brass escape wheel has three crossings.
A mixed impulse escapement.
No of teeth embraced 32.
Balance and Spring: A free sprung split bimetallic balance with gold compensation screws and quarter nuts. Balance diameter 13.5 mm, thickness 1.13 mm. Blued-steel duo-in-uno spring1 with twelve turns to the flat portion and twelve to the helical portion, attached to a rectangular steel collet on the balance staff and a polished steel stud on the balance cock.
Means of Regulation: Free spring, so the quarter nuts are used to bring the watch to time.
Train Counts and Beat Rate:
Great wheels 86 (barrels)
Intermediate wheel 70 pinion 10
Centre wheel 80 pinion 10
Third wheel 75 pinion 10
Fourth wheel 70 pinion 10
Escape wheel 15 pinion 7
Beat rate: 18,000
Motion work: cannon pinion 12
minute wheel 36, minute pinion 10
hour wheel 40
Winding System: Keyless winding with side-set sliding pinion hand setting mechanism.
Movement: diameter 50.4 mm, height 12.0 mm, pillar height 3.3 mm.
Provenance: Formerly in the Ilbert collection. Ilbert purchased this from Malcolm Gardner 29/9/1932.
Charles Frodsham, in his report on the Great International Exhibition held in 1862 in South Kensington, said that the duo-in-uno balance spring ensures 'almost certainly correct performance in all various positions with a perfectly poised balance'.
A watch movement of the highest quality throughout made for Frodsham by Guillaume, see Mercer, 'Frodsham', p. 256 and illus. pl.77. The Guillaume mentioned in this reference is difficult to identify but it may well be significant that the watch (cat. no. 155 (registration no. 1958,1201.1010)) by Alexander Guillaume has a similar date coding to the AD.Fmsz watches sold by Frodsham. Also, the list of members in the British Horological Institute published in 'Horological Journal', August 1865 includes a C. Guillaume, described as a watch manufacturer. This Swiss watchmaker may well have been related to the Guillaume family of watchmakers whose business was at 16 Myddleton Square, Islington, London. Whether or not the movement of this watch was made for Frodsham in Switzerland or London remains open to question, although a London origin would seem more likely.
For other examples of other watches by Frodsham with the AD.Fmsz inscription see Cat. nos. 147 (registration no. 1958,1201.915), 152 (1958,1201.997), 154 (1958,1201.999), and 164 (1958,1201.1000). See also cat. no 147 for an explanation of the code. Also in the British Musueum Collections is the movement and dial of a club tooth lever watch inscribed 'Arnold CHAS. FRODSHAM 7516 AD.Fmsz' (registration no. 1958,1201.919 (MLA CAI-919)).
- 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.1001 (Ilbert Collection)
Previous owner/ex-collection number: M171 (Ilbert Ledger)