The Chester R. Longwell Professional Papers (1886-1974) document Longwell's professional career as a geologist and his pioneering field work in Clark County, Nevada. Included are Longwell's field notes; manuscripts, articles and speeches related to geology; personal and business correspondence; professional publications; subject and name files; specimen tags; photographic prints, negatives, and slides; and geological and topographical maps, primarily of Nevada, California, Arizona, and Utah.