Of the three surgeons who accompanied Custer's Seventh Cavalry on June 25, 1876, only the youngest, twenty-eight-year-old Henry Porter, survived that day's ordeal, riding through a gauntlet of Indian attackers and up the steep bluffs to Major Marcus Reno's hilltop position. But the story of Dr. Porter's wartime exploits goes far beyond the battle itself. In this compelling narrative of military endurance and medical ingenuity, Joan Nabseth Stevenson...