Beschreibung:

Patek Philippe & Cie. An Exceptionally Rare and Possibly Unique Set of Three Torpedo-Boat Navigator’s Trio Silver Openface Pocket Watches with Power Reserve and Original Fitted Box, Sold to the US Navy on 8 December, 1917 and used on US Zeppelin (Airship) Los Angeles (ZR-3) Signed Patek Philippe & Cie., Movement No.’s 170’414, 170’416, 170'417, Case No.’s 274’699, 274’701, 274’693, Manufactured in 1912 Movement: Manual, double numbered, Cal. 21’’’, equidistant lever escapements, controlled by Guillaume balances with “winged” arms, gold temperature adjustment screws and platinum mean time screws, special alloy Breguet balance spring with Phillips’ inner and outer terminal curves to assure isochronism, diamond endstone, “swan-neck” micrometric regulator, Patek Philippe & Cie . keyless winding (Swiss patent 2680, 27 September 1890) Dial: Silver champlevé, Roman numerals, outer railway minute track, subsidiary seconds, power reserve Case: Silver, each with engraved hinged case backs reading; US NAVY, each 60mm diam.,set within an original fitted US NAVY mahogany box with three compartments, each numbered on a brass plate with the corresponding watch’s serial number, marked ‘ ZR-3 ,’ glazed apertures, a provision for placing the Trio in 60° upright position, presumably for easier observations, box 10 x 4.5 x 2.25 inches Signed: Cases, dials and movements signed Accompanied By: Three Patek Philippe Geneva Observatory Rating Certificates obtained on May 8, 1913, Three Patek Philippe Extracts from the Archives confirming date of sale on December 8, 1917