This primary source comes from the Records of the Patent and Trademark Office.
National Archives Identifier:
6277786Full Citation: Patent Drawing for R. J. Spalding's Flying Machine; 3/5/1889; Records of the Patent and Trademark Office, Record Group 241. [Online Version, https://www.docsteach.org/documents/document/patent-drawing-for-r-j-spaldings-flying-machine, April 19, 2024]