This notebook covers the period December 1879-March 1880. Tt contains tables relating to tests on experimental lamps, numbers 141 to 973. Most of the entries are by Francis Jehl, but there are also occasional notes by other laboratory workers. Related material can be found in Menlo Park Notebook #19. The label on the front cover is marked "Lamps" and "Electric Light." The book contains 284 numbered pages.
Missing page numbers: 33-34, 121-122, 159-176, 247-248, 253-254, 257-264, 267-270, 275-276. Courtesy of Thomas Edison National Historical Park.