This notebook dates from July 1880. Most of the entries are by Edison and consist of drawings that appear to be related to the ore separator. There are also a few pages of notes, possibly by Martin Force, relating to connections in the photometer room. The label on the front cover is marked "Ore Milling" and "Martin Force." The book contains 282 numbered pages.
Blank pages: 8-279. Courtesy of Thomas Edison National Historical Park.