Ami Lecoultre split-seconds chronograph pocket watch movement in working-case
Record status
Individual type · partial
Period
circa 1888
According to the auction catalog, this open-face pocket watch movement housed in a white metal working-case was manufactured circa 1888 by Ami Lecoultre of Le Brassus and Geneva.
It features a 20-ligne rhodium-plated three-quarter plate movement with a straight-line lever escapement and a patented non-magnetic compensated balance. Horological complications reported by the source include a 1/4-second chronograph with an oscillating pinion device operated by a crown push-piece, a split-seconds function controlled at 11 o'clock, and a 1/4-second foudroyante subsidiary dial at 6 o'clock. The dial is white enamel with radial Roman numerals and blued steel pear hands.
Evidence at a glance
- Linked sources
- 1
- Photograph views
- 1
- Catalogue references
- 0
Counts describe this entry’s documentation, not authenticity, rarity or completeness. Photographs may show one specimen; check each caption and licence.
Technical characteristics
- Dial
- White enamel dial with radial Roman numerals
- Type
- Split-seconds chronograph pocket watch
- Hands
- Blued steel “Pear” hands
- Caliber
- 20’’’, lever escapement
- Dimensions
- Ø 47.1 mm
- Place recorded
- Switzerland
- Movement Number
- 3 482
- Maker / attribution
- Ami Lecoultre
Design
- Visible features
- • Open movement side displaying chronograph steel levers, wheels, column wheel, and gold-filled cursive engravings. • Engravings legible on the movement plates include 'No 3482', 'Adjusted', 'Non-magnetic', and 'Ami Lecoultre / Le Brassus & Geneva'. • Fitted with a prominent fluted winding crown atop the case pendant.
- Identity and Horological Complications
- This object consists of a 20-ligne open-face pocket watch movement housed in a white metal working-case, catalogued by the auctioneer as manufactured circa 1888 by Ami Lecoultre of Le Brassus & Geneva. It carries movement number 3 482 and measures 47.1 mm in diameter. The catalog notes that it is accompanied by copies of invention patents associated with its mechanisms. The catalog lists three specific complications for the movement: a 1/4-second chronograph utilizing an oscillating pinion device operated through a push-piece in the winding crown, a split-seconds function controlled via a push-piece on the case band at 11 o'clock, and a 1/4-second foudroyante display situated on a subsidiary dial at 6 o'clock.
- Visible Movement Construction and Finishes
- Direct observation of the movement side reveals chronograph steel levers, intermediate wheels, a column wheel mechanism, and gold-filled cursive engravings. The plate engravings read 'No 3482', 'Adjusted', 'Non-magnetic', and 'Ami Lecoultre / Le Brassus & Geneva'. A fluted winding crown is visible atop the case pendant. According to the auction catalog description, the movement is a 20-ligne, 3/4-plate caliber with rhodium plating, a going barrel, and a straight-line equilibrated lever escapement. The catalog also specifies an index regulator with a swan-neck spring and an eccentric snail precision-regulating mechanism for fast/slow adjustment, alongside a balance fitted with gold poising screws and a blued steel hairspring with terminal curve.
- Source Documentation and Unverified Elements
- The catalog entry notes that the movement mechanism is based on American patent No. 355 403, granted on January 4, 1887, to Ami LeCoultre for a 'Stop Watch.' The balance is described as a patented non-magnetic platinum alloy and brass compensated balance linked in catalog notes to American patents issued in May and August 1888 to Heinrich Ostermann, Axel Prip, and Charles Lacroix. Because the provided photograph only shows the movement side, elements on the reverse side are not visually verified. Descriptions of the white enamel dial with radial Roman numerals, the blued steel pear hands, and the foudroyante subsidiary dial at 6 o'clock rely entirely on the auction catalog text.
Identification
- Serial number
- 3 482
- Source note
- Facts transcribed from the linked source listing or collection record. Attribution and specifications are source-reported and have not been independently authenticated.
Catalogue references
No catalogue numbers recorded. Numbers are only published once transcribed from a verified edition of a standard catalogue — they are never inferred.
Research required
- Research required: Catalogued specifically as a pocket watch movement housed in a working-case rather than a finished commercial case.
- Research required: Details of the foudroyante dial, hands, and balance alloy composition are source-reported and not visible in this movement-side photograph.