This primary source comes from the Records of the Office of the Chief Signal Officer.
National Archives Identifier:
526779Full Citation: Samuel F.B. Morse, inventor of the telegraph; ca. 1860 - 1865; 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/samuel-fb-morse-inventor-of-the-telegraph, May 4, 2024]