Even among the mighty mountain men, Jim Bridger was a towering figure. He was one of the greatest explorers and pathfinders in American history. He couldn't write his name, but at eighteen he had braved the fury of the Missouri, ascending it in a keelboat flotilla commanded by that stalwart Mike Fink. By 1824, when he was only twenty, he had discovered the Great Salt Lake. Later he was to open the Overland Route, which was the path of the Overland...