This notebook covers the period April-October 1901. At the beginning of the book are notes by Edison regarding storage batteries, including entries detailing the use of cells by the Edison Electric Illuminating Co. of Brooklyn. Most of the book contains an enumerated log of 551 nickel grid experiments. The entries are primarily by unidentified experimenters, although there are some entries by Edison. Only the pages that include the Edison entries, experiment numbers 1-36 and 477-509, have been selected. Inserted into the book are two loose pages containing Edison's plans for an iron ore separation plant, probably in the Dunderland region of Norway, along with several pages of notes by Edison relating to the nickel grid tests. The front cover is marked "April 01." The pages are unnumbered. Approximately 100 pages have been used.