SAN DIEGO, CALIFORNIA—Two bottle-nosed dolphins found a late nineteenth-century Howell torpedo in the waters off Coronado Island during training exercises with the U.S. Navy to find undersea objects. Navy specialists disregarded a positive response from the first dolphin because they had not placed any training devices, made to look like mines, in the area. When a second dolphin training in the same area alerted the crew a week later, it was asked to mark the spot of its discovery. Human divers found the Howell torpedo in two pieces and brought it to the surface for identification. “We’ve never found anything like this. Never,” said Mike Rothe, who heads the Navy’s marine mammal program. The Howell torpedo was the first that could follow a track without leaving a wake and then hit its target. Only 50 of them were made between 1870 and 1889—the only other known surviving example is on display at the Naval Undersea Museum in Keyport, Washington.