Silver-cased half-hunter wrist-watch

Description — British Museum

Wrist-watch. Half-plate movement. Club-tooth lever escapement. White enamel dial with Arabic hour numerals; the 12 in red; outer ring for minutes; sunk subsidiary seconds. Second hand missing. Half-hunter silver case with hinged cover and integral back; engraved Arabic numerals surrounding minute circle bordering a central aperture.

Curator's comments — British Museum

Comment from Richard Good, Catalogue of Watches in the British Museum. Vol. V (Unpublished manuscript) Made by Waltham Watch Co. America, c. 1900. Watch with club tooth lever escapement. Signature: On the dial 'Waltham U.S.A.' On the train bridge 'Waltham SEVEN JEWELS U.S.A.' On the barrel bridge 23511645. Case: A silver half hunter case with in the back 'DESGN REG'D A.W.C.CO' a number 1065109 and the firms trade mark; a wheel with two wings with beneath 'STERLING'. The inner silver bezel is mounted on the nickel silver dust ring which acts as an adaptor and to which the movement is fixed. Only the hinged case front keeps the movement in the case. This case front is engraved with hours and minutes and has large Arabic numerals. The engraving is filled black but a lot of this filling is missing. Dial & Hands: A slightly domed enamel dial with Arabic numerals the 12 in red. A sunk subsidiary seconds dial. Blued-steel spade pattern hour hand, the other hands missing. Movement: Ebauche Marks: 23511645 Frame: A nickel silver frame, damaskeened. A bridge for the barrel, centre and third wheels, and another for the fourth and escape wheels. A cock for the pallets and another for the balance. Under the fourth and escape wheel bridge is 377036, under the balance cock is 11645. Barrel and Mainspring: A separate arbor passes through the great wheel which has a snailed arbor fixed to it. A steel barrel, internal diameter 11.75 mm, height 2.00 mm. Mainspring: height 2.00 mm, thickness 0.115 mm. Barrel Arbor: diameter 3.85 mm, snailed. Hooking: Round Train: All the brass wheels gilded, the centre wheel, third and fourth wheels with five crossings. The brass escape wheel with four. The great wheel of nickel silver. Jewelling: Jewelled bearings to the balance with these in screwed settings. Clear sapphire endstones. Escapement: A straight line layout club tooth lever escapement with short lever, double roller and D-shaped impulse pin. The exposed pallet stones have flat acting faces. A brass escape wheel with four crossings and convex impulse faces. An equidistant locking escapement. Adjustable banking pins. No. of teeth embraced 3½. Balance & Spring: a split bimetallic balance with brass compensation screws and two brass timing screws. Balance diameter 11.45 mm, thickness 0.9 mm. The balance spring is missing. Means of Regulation: An index on the balance cock registers against a divided scale with 'F S' engraved on the balance cock table. Train Counts and Beat Rate: Great wheel 70 (barrel) Centre wheel 64 pinion 10 Third wheel 60 pinion 8 Fourth wheel 70 pinion 8 Escape wheel 15 pinion 7 Beat rate: 18,000 Motion work: cannon pinion 10 minute wheel 30, minute pinion 10 hour wheel 32 Winding System: Negative set keyless work. When the movement is out of the case it will normally be in the hand set position with negative set keyless work. However this watch is furnished with a lever whose nibbed head is inset into the movement edge. When this is pulled out it puts the keyless work into the winding position. This allows the watchmaker to run the movement whilst it is out of the case without the interference from the keyless work that would occur if it was to be left in the handset position. Dimensions: Case: Diameter 33.4 mm., height 8.4 mm. Movement: Diameter 28.4 mm., height 7.0 mm. Provenance: Purchased in 1987 with the aid of funds from the Dingwall Bequest.