Nickel-plated cased club-tooth lever wrist watch

Description — British Museum

Ingersoll Rex wrist-watch. 7 jewel Swiss movement with club-tooth lever escapement; keyless winding and hand-setting. Silvered dial with Arabic hour numerals and subsidiary seconds. Blued-steel hands. Nickel-plated metal case.

Curator's comments — British Museum

Comment from Richard Good, Catalogue of Watches in the British Museum. Vol. V (Unpublished manuscript) Made by Ingersoll Switzerland, c. 1960 Wrist watch with a club tooth lever escapement. Signature: 'INGERSOLL REX SWISS MADE' on the dial. Case: A basically rectangular, chrome plated two piece case much the worse for wear. Inside the back is stamped 'INGERSOLL NICKEL-CHROMIUM SWISS MADE'. Fixed wire lugs. The 'glass' is crazed and discoloured. Dial & Hands: A silvered metal dial now stained with, in black, Arabic numerals and minute circle. A subsidiary seconds dial. The dial secured by screws from the side of the front plate. The hands in blued -steel. Movement: A round movement of nickel silver. Ebauche Marks: On the inside of the front plate is 3. Frame: a bridge for the keyless work and barrel one for the train and cocks for the pallets and balance. The barrel bridge marked 'SWISS MADE' and the train bridge 'CAL 101 7 RUBIES' and 'INGERSOLL'. Barrel and Mainspring: A going barrel with a recessed cover. Barrel: I diameter 9.5 mm., height 1.5 mm. Mainspring: height 1.4 mm., thickness 0.125 mm. Barrel Arbor: diameter 3.0 mm., snailed. Hooking: Punched from the barrel wall. Train: All the wheels gilded, the centre wheel, third and fourth wheels with five crossings. The steel escape wheel with four. Jewelling: Jewelled bearings for the balance, the jewels pressed in. Ruby endstones to the balance jewels. 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, one of the stones is chipped. A steel escape wheel with four crossings. An equidistant locking escapement. No. of teeth embraced 3½. Balance & Spring: a monometallic balance with brass screws. Balance diameter 9.0 mm., thickness 0.7 mm. A blued-steel flat spiral spring with 10 turns. Means of Regulation: An index on the balance cock registers against a divided scale with 'F S' and 'A R' engraved on the balance cock table.The curb pin is broken off leaving the boot alone. Train Counts and Beat Rate: Great wheel 70 (barrel) Centre wheel 64 pinion 10 Third wheel 60 pinion 8 Fourth wheel 60 pinion 8 Escape wheel 15 pinion 6 Beat rate 18,000 Motion work: cannon pinion 10 minute wheel 30, minute pinion 8 hour wheel 32 Winding System: Stem set positive keyless work, the bolt broken. Dimensions: Case: Length 36.2 mm., width 25.2 mm., height over the glass 7.7 mm. Movement: diameter 23.6 mm., height 6.1 mm. Provenance: Donated by Heron Corporation Ltd in 1983.