07/26/1875 Batchelor, Charles and Edison, Thomas Alva -- Technical Notes and Drawings
(Wurth, Charles Nicholaus; Adams, James [supplied or conjectured]; Edison, Samuel Ogden, (Father)) Electricity and magnetism
[NE1676]  Notebook Series -- Newark Shop Notebooks: Cat. 1172 Bound Notebook (1871-1872, 1874-1875)
[NE1676258A; TAEM 3:156]
Courtesy of Thomas Edison National Historical Park.