"You seriously mean to tell me that the ship is doomed?" asked Frank Worsley, commander of the Endurance, stuck impassably in Antarctic ice packs. "What the ice gets, " replied Sir Ernest Shackleton, the expedition's unflappable leader, "the ice keeps." It did not, however, get the ship's twenty-five crew members, all of whom survived an eight-hundred-mile voyage across sea, land, and ice to South Georgia, the nearest inhabited island. First...