Proceed with all possible rapidity and power. Both versions refer to the steam engine in ships and locomotives, as does with a full head of steam. “Full steam” meant a boiler that had developed maximum pressure. The terms became popular through an order attributed to David Glasgow Farragut at the Battle of Mobile Bay (Aug. 5, 1864): “Damn the torpedoes! Full steam ahead!” (Torpedoes in those days referred to mines.) They were transferred to nonmilitary enterprises soon afterward, but ironically one of them resurfaced in literal fashion more than a century later. In 1989 environmental activists from the Greenpeace movement sailed out among U.S. Navy boats that were testing torpedoes off the coast of Florida in order to impede what they perceived as a hazard to the surrounding ecology. The Greenpeace order of the day was, again, “Damn the torpedoes! Full speed ahead,” and the navy, either unwittingly or on purpose, collided with the Greenpeace vessel, which was severely damaged.