Important Collectors’ Wristwatches, P...

New York, Dec 05, 2007

LOT 324

Silver Weems Longines, ?Weems?, movement No. 4931593, case No. 4931593. Made in the 1930s. Fine and very rare, hour angle, large, center seconds, silver aviator's wristwatch.

USD 10,000 - 12,000

EUR 7,000 - 8,000

Sold: USD 15,340

C. Four-body, massive, polished, hinged back, ball-shaped winding-crown, additional stem on the band to set the center dial time, hinged silver cuvette, rounded bezel, concave lugs. D. White enamel with painted black Arabic numerals, outer minute track, at the centre a revolving matte silver dial to adjust the time in seconds. Blued steel Breguet hands. M. Cal. 18.69N, rhodium-plated, 15 jewels, straight-line lever escapement, bi-metallic balance, self-compensating Breguet balance-spring, index regulator, adjusted to three positions. Dial, case and movement signed. Diam. 48 mm. Thickness 15,5 mm. Property of Various Owners


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Grading System
Grade: AAA

Excellent

Case: 3

Good

Movement: 3*

Good

Overhaul recommended, at buyer's expense

Dial: 3-01

Good

HANDS Original

Notes

The hour angle system was invented by Philippe Vanhorn Weems of the Annapolis Naval Academy, who was an authority in the 1920s and 30s. He trained the famous Charles A. Lindbergh, who set the record for the first non-stop transoceanic flight. This watch bears a large ball-shaped winding-crown, enabling the watch to be wound by a pilot wearing gloves. It is practically impossible to build a commercial timepiece which will keep time to the exact second under the conditions met in a ship or in an aeroplane. The unavoidable variation in the chronometer from true time necessitated an extra calculation in navigation to compensate for this chronometer error. Weems noted that in an airplane moving at speeds of 200 to 300 miles an hour or more, the time required for calculating chronometer error was a danger that should be eliminated. Since the high gear ratio made it impractical to set the second hand to the dial, Weems chose to set the dial to the hands. The seconds dial in the center of the watch is rotated by depressing the small stem. For navigation purposes, the Greenwich Mean time is indicated directly. The Longines Weems Watch is made in two models. The smaller model is useful not only for sea navigators and aircraft pilots, but particularly radio broadcasters as well as others, such as civil engineers who require exact time.