02/09/1874 [Supplied year] Batchelor, Charles and Edison, Thomas Alva -- Technical Notes and Drawings
Automatic telegraphy
[NM007]  Notebook Series -- Miscellaneous Shop and Laboratory Notebooks: Cat. 1175 Bound Notebook (1873-1874)
[NM007163; TAEM 6:186]
Courtesy of Thomas Edison National Historical Park.