L’Heure de l’Observatoire” Longines

“L’Heure de l’Observatoire” Longines, Swiss, No. 7513094. Made circa 1935. Fine and rare, lever deck chronometer with split seconds chronograph, 36-hour power reserve indication and special device with revolving disc to set time to within a fraction of a second. Aluminium with reeded bezel, buttons on the band for stop/ start, the split seconds, and revolving the chronograph scale, mounted in a two-body mahogany box with hinged lid, the interior fitted with a plaque inscribed “Le Chronometre Longines Donne Exactement L’Heure de L’Observatoire”. Brushed silver with black Arabic numerals, outer minute track, outermost revolving chronograph ring with blue-painted second and fifths of a second divisions, Arabic five-second numerals, power reserve sector. Blued steel “spade” hands. Cal. 2129, 19’’’, rhodium-plated, "fausses côtes" decoration, 26 jewels, straightline lever escapement with gold pallet fork, monometallic balance, self compensating blued steel Breguet balance spring with special micrometric regulator, split seconds chronograph with visible work. Dial, box and movement signed. Dial diam. 70 mm. Box dim. 16 x 14 x 6 cm. Notes The split seconds hand has to be stopped at the hour signal; the revolving chronograph ring must be turned in order to set the division "60" facing the split seconds hand, which is then released to join the other chronograph hand. The chronometer is therefore set to time within a fraction of second. The aluminium case, monometallic balanc