This notebook covers the period August-November 1879. Most of the entries are by Francis Upton and Francis Jehl. There are also entries by Charles Batchelor and Samuel D. Mott. Included are notes, calculations, and drawings relating to experiments with metal filaments, carbon filaments, and vacuum pumps. The label on the front cover is marked "Tests of Spirals and pumps Aug. 23 '79" and "F R Upton." The book contains 282 numbered pages.
Blank pages: 82-83, 232-233, 246-249, 272, 275.
Missing page numbers: 265-266, 269-270, 273-274. Courtesy of Thomas Edison National Historical Park.