Danish gold minute repeating hunting cased watch Circa 1855

Gold minute repeating pocket watch by Jules Jürgensen
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A Danish rare and fine minute repeating gentleman’s hunting cased pocket watch, circa 1855. Nickel movement, 31 jewels, straight line calibrated long lever escapement, cut bimetallic compensation balance with blued steel Breguet balance spring, early minute repeating mechanism with all-or-nothing and automatic surprise piece, repeatng on gongs by a slide in the band.
Engine-turned case with reeded band, gold hinged cuvette with winding and setting apertures.
White enamel, radial Roman numerals, outer minute ring, subsidiary sunk seconds. Blued steel Breguet hands.
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Diameter: 54 mm
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Signed: Jules Jürgensen, Copenhagen
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A rare example of an early nickel movement and of an early minute-repeating mechanism still based on the movable star wheel. About five years later, Audemars was to invent a mechanism with fixed star making the hour-repeating change more precise and consequently enabling minute-repeating work to be more accurate. Before, makers had struggled with accurate repeating at the end and beginning of the hour. The watch also employs an early so called “instantaneous surprise piece”, which guarantees corect minute-repeating at the moment of the hour change, the most difficult aspect in early minute-repeaters with moving star wheel. In this case the piece engages the mechanism only when the repeater is activated. For a biography of Jules Jürgensen.