Patek Philippe Ref. 1518 Perpetual Calendar Chronograph Moonphase Watch - Men's manual winding vintage wristwatch, featuring perpetual calendar, moonphase and chronograph. 18k yellow gold three body case (35mm diameter) with snap-on case back engraved Arthur M. Wirtz, 1420 Lake Shore Drive. Silver dial with raised gold Arabic numerals. Black strap band with 18k yellow gold Patek Philippe buckle. Previously owned by Arthur M. Wirtz, ca. 1946, sports entrepreneur, owner of the Ice Follies and Holiday on Ice as well as promoter of Sonja Henie, Jo Jo Starbuck and Dorothy Hamil. Only 281 pieces of the Patek Philippe Ref. 1518 were produced from 1941 - 1954. This series was the first to combine a perpetual calendar with a chronograph. This is an important piece, extremely rare and very collectible. Pre-owned, vintage, with original Patek Philippe inner and outer boxes and archival papers.