Walker Evans's career spread over 46 fitful and prolific years, yet in a scant two, 1935-1936, he produced the singular body of work that came to define him. During that brief time, while working for the Farm Security Administration (previously the U.S. Resettlement Administration) photographing the consequences of the Great Depression, he refined a hybrid style that combined documentation with sly personal comment. He delighted in traveling incognito...