This primary source comes from the Records of the Office of the Chief Signal Officer.
National Archives Identifier:
524951Full Citation: Fortifications in front of Atlanta, Ga.; 1864; Mathew Brady Photographs of Civil War-Era Personalities and Scenes, 1921 - 1940; Records of the Office of the Chief Signal Officer, Record Group 111. [Online Version, https://www.docsteach.org/documents/document/fortifications-in-front-of-atlanta-ga, April 19, 2024]