Swiss double faced watch with chronographs and recorders Circa 1930

Gold Anti Magnetic watch with four complications by Longines.
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A Swiss, double faced, keyless winding pocket watch, Anti Magnétique, with two chronographs, and minute recorders, circa 1930.
Gilded brass movement, going barrel, straight line equilibrated lever escapement, monometallic screw balance and self compensating Breguet hairspring, index regulator; chronograph work on the top plate. Round shaped 18 Carat yellow gold case. White enamel dial with suspended Breguet style numerals, outer minutes/seconds track, and original gold pear hands. On the reverse, white enamel with multi colour double scales (counter enamel signed Z.J.).
This watch has four horological complications: The first dial features: • 1/5 second chronograph (activated by the single round push piece located on the winding crown) with an outer ring divided in 300; • Instantaneous 30 minute recorder (subsidiary dial at 12 o’clock). The second dial features: • 1/5 second chronograph (activated at the same time; the chronograph hand turns counter clockwise) with two Archimedean spiral telemetric scales graduated for 1 000 metres, for one to five minutes base; • Instantaneous 5 minute recorder (sector at 12 o’clock).
Dial and movement signed. Accompanied by the original fitted box and the Extract from the Archives, dated March 2020, that mentioned this watch was invoiced on October 27, 1930, to the Longines agent, Maison Ostersetzer, Italy.
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Diameter: 51 mm
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Signed: Longines, Saint-Imier
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The watch must have been destined for measuring very high speeds since a second dial was intended just for calculating speeds over 240 km / h. At the time, such speeds were encountered in scientific experiments and aviation (a Bugatti could go to 120 km / h). The main dial measured sailing, running, and car races. The reverse dial was for aviation and scientific measurements.