This notebook covers the period February-November 1879. Most of the entries are by Edison and Francis Upton. There are also entries by Charles Batchelor and Francis Jehl. All of the entries relate to electric light and power experiments, except for one drawing by Batchelor of a telephone circuit. The electric light material includes notes, calculations, and tests of lamps; notes, drawings, and calculations relating to generators; and notes and calculations about electric power distribution. The book contains 278 numbered pages.

Blank pages: 234-277.

Missing page numbers: 51-52, 89-90, 107-108, 279-280.