John James McCook, Jr. (born February 4, 1843) was a chaplain in the Union Army during the American Civil War, and postbellum lawyer, professor, and theologian. He was a member of the Fighting McCooks, a family of Ohioans who contributed 15 members to the Union army. This edition includes his sermons, lectures, notebooks, correspondence, and other papers relating to his sociological investigations, including his extensive study of “tramps” as a social group.