National Archives Identifier: 529276 Local Identifier: 111-B-5171 Creator(s): War Department. Office of the Chief Signal Officer. (08/01/1866 - 09/18/1947) (Most Recent) From: Series : Mathew Brady Photographs of Civil War-Era Personalities and Scenes, compiled 1921 - 1940, documenting the period 1860 - 1865 Record Group 111: Records of the Office of the Chief Signal Officer, 1860 - 1985