Harriet Tubman is among the most famous Americans ever born and soon to be the face of the twenty-dollar bill. Yet often she's a figure more out of myth than history, almost a comic-book superhero. Despite being barely five feet tall, unable to read, and suffering from a brain injury, she managed to escape from her own enslavement, return again and again to lead others north to freedom without loss of life, speak out powerfully against slavery, and then become the first American woman in history to lead a military raid, freeing some seven hundred people. You could almost say she's America's Robin Hood, a miraculous vision, often rightly celebrated but seldom understood.      336 pages  hc