When Eadweard Muybridge, the great photographer of the nineteenth century, demonstrated in photographs that all the feet of a trotting horse are sometimes off the ground at the same time, John-Louis-Ernest Meissonier, the eminent painter of battle scenes and historical subjects, is reported to have realized that his close study of horses over a period of thirty years had never revealed this fundamental truth, and to have said: “Never again shall I touch a brush!” In fact he did touch a brush, in order to repaint the legs of the horses in some of his most famous paintings so that they reflected a truth that could not be verified by the naked eye, thereby, in the words of Rebecca Solnit, altering the mission of painting forever. Meissonier became a great promoter of Eadweard Muybridge, who was the emblematic figure of the age of speed and the anhihilation of time (Muybridge’s own expression), and a character driven by the stuff of fiction. Solnit’s book River of Shadows (Viking Penguin) is a brilliant account of Muybridge’s life and the “Age of the Technological Wild West”: Muybridge was a great inventor and tinkerer, one of the most original of the landscape photographers (his panorama of San Francisco has never been equalled), and a hobnobber with the celebrated and the far-too-rich, such as Leland Stanford, the robber baron of California. As well, Muybridge murdered his wife’s lover in cold blood and was found by a jury to have been temporarily insane while committing a crime of passion: he got off scot-free. Muybridge photographed the “opening” of the American West, and his photography is part of that great usurpation. This wonderful book demonstrates the emerging world of technology and its entanglement in the new empire, and it is written by someone who knows how to think and write at the same time.