This notebook covers the period December 1887-December 1889. The book contains notes, drawings, and calculations by Charles Batchelor and Arthur E. Kennelly regarding the multipolar dynamo, phonograph motors and magnets, and electrical meter and battery experiments. There are also notes by an unidentified experimenter relating to the electrical distribution system in Llewellyn Park and to other Galvanometer Room projects. The front cover is labeled "#497" and is inscribed "Multipolar Dynamo." The spine is labeled "44." The pages are unnumbered. Approximately 90 pages have been used. Courtesy of Thomas Edison National Historical Park.