Chrome-plated cased pin-pallet lever wrist-watch with leather wrist-strap

Description — British Museum

Ingersoll de luxe wrist-watch. 15 jewel Swiss movement with club-tooth lever escapement; keyless winding and hand-setting. Silver coloured metal dial with Arabic hour numerals and subsidiary seconds. Hour and minute hands originally with an infill of luminous paint. Chrome-plated case. Complete with light brown wrist-strap. Glass is yellow tinted.

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 V (Unpublished manuscript) Made by Ingersoll Switzerland c. 1955 Wrist watch with a club tooth lever escapement. Signature: On the dial 'INGERSOLL DE LUXE' and ' SWISS MADE' Case: A round nickel chromium plated tonneau case with a snap on back and bezel.… Complete with a light brown leather strap - a replacement. Inside the back is 'INGERSOLL NICKEL - CHROMIUM SWISS MADE' An antimagnetic cover snapped on inside the back of the case. Dial & Hands: A silvered metal dial with black Arabic numerals and minute circle and a subsidiary seconds dial. This latter with batons and no numerals. The hour numerals filled luminous. Blued steel skeleton hands once, but no longer, filled luminous. The dial secured with two screws from the side. Movement: Ebauche Marks: None. Frame: A round movement with a nickel silver frame finished with Geneva stripes. Signed on the barrel bridge 'SWISS MADE' and on the train bridge 'INGERSOLL 15 RUBIES CAL 102' Barrel and Mainspring: A recessed cover to the going barrel. Barrel: I diameter 9.1 mm., height 1.46 mm. Mainspring: height 1.42 mm, thickness 0.11 mm. Barrel Arbor: diameter 2.92, snailed. Hooking: pressed from the barrel wall. Train: All the brass wheels are gilded, the centre, third and fourth wheels with five crossings. The steel escape wheel with four. Jewelling: 15 jewelled bearings from the third wheel onwards. All 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. A steel escape wheel with four crossings. The acting faces of the pallet stones flat. An equidistant locking escapement. No. of teeth embraced 3½. Balance & Spring: A monometallic balance with brass screws. Balance diameter 8.7 mm, thickness 0.63 mm. A blued-steel flat spiral spring with 10 ¼ 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. Train Counts and Beat Rate: Great wheel (barrel) 70 Centre wheel 64 pinion 10 Third wheel 60 pinion 8 Fourth wheel 60 pinion 8 Escape wheel pinion 6 Beat rate 18,000 Motion work: cannon pinion 10 minute wheel 30, minute pinion 8, hour wheel 32 Winding System: Conventional positive stem set keyless work. Dimensions: Diameter of bezel 26.2 mm. Height 8.8 mm., over the glass. Movement: Diameter 23.6 mm., height 6.3 mm. Provenance: Donated in 1983 by The Heron Corporation Ltd.