Series 4 ("Photographs") of the William J. Hammer Collection consists of twenty-three boxes of prints and glass-plate negatives arranged into three subseries: (1) photographs relating to Hammer; (2) Edisonia photographs; and (3) photographs relating to reference materials. Nine of the boxes are oversize. Included are photographs of Edison's laboratory at Menlo Park, his first lamp factory, and the boarding house at which some of his employees lived. There is also a portrait of Edison's father, Samuel, taken in Orange, New Jersey, in 1891, as well as a photograph of the Weekly Herald, the newspaper he published as a youth.