Best known for his role in the arrest and killing of Crazy Horse and for the book he wrote, The Indian Sign Language, Captain William Philo Clark (1845-1884) was one of the Old Army's renaissance men, by turns administrator, fighter, diplomat, explorer, and ethnologist. As such, Clark found himself at center stage during some of the most momentous events of the post-Civil War West: from Brigadier General George Crook's infamous "Starvation...