“A monument to a dying race, and a monument to myself”: so George Catlin, antebellum painter of the American Indians, described his “Indian Gallery”. Largely self-taught and self-supporting, Catlin undertook the most ambitious documentary project of his time, his aim being to produce a “graphic delineation of the living manners, customs, and character of an interesting race of people, who are rapidly passing away from the face of the earth . . . thus snatching from a hasty oblivion what could be saved for the benefit of posterity, and perpetuating it, as a fair and just monument, to the memory o…