Hartman Bache, who had supervised the construction of the lighthouse, returned to the island and proceeded to build a novel fog signal. Intrigued by a large blowhole, Bache harnessed this natural source of forced air, by placing a whistle atop a chimney constructed over the blowhole. Unfortunately, the high surf needed to power the signal did not always coincide with the periods of dense fog. In 1875, a powerful storm produced a strong surge that blew the chimney off its foundation and ended the days of the ingenious fog signal.