- Museum number
MOVEMENT OF A HUNTER-CASED LEVER WATCH WITH CASE-ACTION WINDING.
Bar movement; going-barrel; gold train-wheels.
Club-tooth lever escapement; split bi-metallic balance; wound up by opening the cover of the case.
Hunter case missing.
- Production date
Diameter: 42.90 millimetres (front-plate)
Thickness: 10.50 millimetres
- Curator's comments
- Comment from Richard Good, Catalogue of Watches in the British Museum. Vol. V (Unpublished manuscript)
Made by B. Haas Jne
France, c. 1870
Self winding watch movement with club tooth lever escapement.
Signature: 'B HAAS J & C BREVETÉS S.D.G.D. PARIS GENEVA'
Dial and Hands: Missing.
Ebauche marks: 14106
Frame: Nickel silver bar movement, the barrel bridge located by four turned pillars and secured by screws. All the screws left bright. Steel pallet bridge.
Barrel and Slipping Mainspring: Barrel I. diameter 16.5 mm., height 2.80 mm.
Recessed cover to the going barrel.
Tapered Mainspring: height 2.65 mm, tapering from 0.32 to 0.19 over the first 150 mm. The spring tapered to ensure slipping at a late stage of winding.
Arbor: 5.3 mm diameter, snailed.
Train: Five wheel train, the intermediate, centre, third and fourth wheels with five crossings, the escape wheel with four.
Jewelled: From the third onwards, all jewels bombé, the escapement with ruby endstones set in steel endpieces.
Escapement: Club tooth lever escapement, layout, double roller with D shaped stone. The escape wheel recessed, the teeth chamfered from both sides. The pallets with long arms, although the pallets are not poised. Screwed on dart. Exposed pallet stones, the acting faces flat.
No. of teeth embraced 3 ½.
Balance and Spring: Split bimetallic balance with gold compensation screws. Balance diameter 15.80 mm., thickness 1.05. Blued-steel flat spiral spring with 16 turns and a terminal curve. Stud clamped and with lateral adjustment.
Means of Regulation: Index on the balance cock registering against a divided scale with engraved 'Avance Retard'
Train Counts and Beat Rate:
Great wheel (barrel) 80
Intermediate wheel 80 pinion 12
Centre wheel 80 pinion 40
Third wheel 75 pinion 10
Fourth wheel 70 pinion 10 The extended seconds pivot broken off.
Escape wheel 15 pinion 7
Beat Rate: 18,000
Motion Work: only the cannon pinion survives, it has 12 leaves.
Winding System: Would wind the watch when the hunter case cover is opened and closed. The movement is hand set by a side lever. Part of the self winding linkage is broken off and missing.
Dimensions: Movement diameter 43.0 mm., height 10.5 mm.
Provenance: Formerly in the Ilbert collection, Ilbert purchased this from Green 24/5/1936
B. Jenne HAAS Besançon. Exhibited in Paris in 1867. Died 1890. He patented in 1866 improvements to escapements and a remontoire in 1867.
- Not on display
Latest: 3 (2017)
4 (1994) Corrosion on train-wheels.
- 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.1011 (Ilbert Collection)
Previous owner/ex-collection number: P75 (Ilbert Ledger)