The Essence of TimeDeciphering watch trends at the Baselworld fair, held April 25–May 2 in Switzerland, is no small feat—the show boasts about 500 watch exhibitors, each promoting a slew of novelties. This year, however, a few themes emerged.The Product: Adventurers’ WatchesPilots and divers and racers—oh, my! In Basel, the industry’s preoccupation with dive watches ­culminated in a splashy news conference honoring the 60th ­anniversary of the Blancpain Fifty Fathoms, the ­20th-century’s iconic dive watch. Elsewhere, brands filled out the sports category with extreme-minded introductions designed to satisfy armchair pilots, automotive fans, and, in the case of Breitling’s new Emergency II model, explorers with a penchant for roaming terra incognita.The Obsession: Mechanical AccuracyCarrera MikroPendulum in 45 mm titanium case; CHF35,000 ($37,425); TAG Heuer, Springfield