Thematic Auction in Geneva:The Evolut...

Hotel Noga Hilton, Geneva, Nov 16, 2002

LOT 436

Isaac Grasset & Cie, Geneva, circa 1898.Interesting and rare silver keyless watch with special patented power source.

CHF 3,000 - 4,500

EUR 2,000 - 3,000

Sold: CHF 3,680

C. Four-body, "bassine", polished, glazed silver cuvette. D. White enamel, Roman numerals, outer minute track with five-minute Arabic figures, subsidiary sunk seconds. Blued steel, "spade" hands. M. 43 mm. (19'''), Grasset bridge caliber, 15 jewels, straight line lever escapement, cut bimetallic compensation balance, Breguet balance spring, power source in the form of a narrow coiled spring wound around the winding stem which terminates with a gear meshing with the center wheel pinion.Signed on dial and movement.Diam. 50 mm.


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Grading System
Grade: AA

Very good
Case: 3

Good
Movement: 3*

Good

Overhaul recommended, at buyer's expense
Dial: 3 - 01

Notes

In the early 1880's Isaac Grasset designed an interesting alternative power source in the form of a coiled spring wound around the stem (Swiss patent No. 120, later improved in No. 5019). In 1897 he patented a stem winding and setting mechanism for the arrangement, as found in this watch (Swiss patent No. 14528). He also patented an interesting constant force escapement and applied it to his design. To date, no example of this is known.