57,500 HKD
Haas - Patent Keyless Cover Winding B. Haas Jeune, de S. M. l’Empereur, Genève, Besançon- Paris, "Remontoir Perpetuel, Chronometre", No. 1008. Made circa 1875. Very fine and rare, 18K gold, hunting-cased lever chronometer pocket watch with “remontoire perpétuel à décrochement” keyless cover winding to the English patent (No. 3945) of Benjamin Haas 1873. Five-body, “bassine et filets”, entirely engine-turned and engraved with foliage and geometric patterns, the front cover with central engraved fleur-de-lis beneath a crown, handsetting button in the pendant. Hinged gold cuvette. White enamel, radial Roman numerals, outer minute track with five-minute Arabic numerals, subsidiary seconds. Blued steel Breguet hands. Notes In 1873 Benjamin Haas patented a winding mechanism (English patent No. 3945 of Dec. 2, 1873). The idea was to use the energy generated by closing the front cover to wind the watch. The initial idea was improved upon; his watch features a well developed system with a 36-hour power reserve generated by 12 closings. To achieve this, Haas changed the going train, adding a wheel, which allowed him three hours' winding by a single closing. He designed a safety device disengaging the mechanism when fully wound, which prevents damage to the cover.
Auctioneer:
Antiquorum
Date:
2011-06-25
