This notebook covers the period February-October 1879. Most of the entries are by Edison. There are some entries by Francis Upton. The name of Charles Batchelor appears occasionally as a witness. Material by Edison includes drawings of the electric pen; specifications for an English patent on the electric light system, which cover the lamp, regulator, generator, and meter; notes on electricity and magnetism; and drawings of generators. Material by Upton includes notes and calculations from resistance tests on carbon, chalk, and sulphide of molybdenum, as well as calculations and drawings of electric power distribution Systems. There are also some hand-drawn maps of Europe, Africa, and the Western Hemisphere at the end of the volume. The label on the front cover is marked \"English Patent &c.\"" The book contains 284 numbered pages.

Blank pages: 20, 23-27, 208-213, 222-225, 230-247, 250-251, 256-265, 272-273.

Missing page numbers: 21-22."