The USS Conestoga left the Navy yard at Mare Island, Calif., on Good Friday, 1921, bound for Pearl Harbor, with a complement of 56 sailors. It cleared the Golden Gate at 3:25 p.m. and steamed into the Gulf of the Farallones in heavy seas. Conestoga was a rugged oceangoing tug that had once hauled coal barges for a Pennsylvania railroad. But 17 years after its launch in Baltimore, it had undergone hard use and had a reputation as a “wet boat,” one that shipped water easily. At 4 p.m. that day, as the San Francisco light ship recorded big waves...