This notebook covers the period December 1879-February 1880. At the beginning of the book is a series of notes by Edison on magneto machines and conductors. The rest of the book was used to keep a record of lamps in the laboratory. The entries are probably by Albert Herrick and include a drawing showing the layout of the lamps in the main laboratory building. The label on the front cover is marked "Herrick" and "Account of Lamps." Except for the first page (p.3), the book is unpaginated. Approximately 125 pages have been used. Some pages have been torn out of the book. Courtesy of Thomas Edison National Historical Park.