This letterbook covers the period March-September 1881. Most of the correspondence is by Edison. There is also correspondence by Samuel Insull. Most of Edison's letters are in the hand of Insull, acting as Edison's secretary. The correspondence relates primarily to electric lighting. Included are letters concerning the establishment and financing of Edison's manufacturing operations, the lighting of Menlo Park, infringements of Edison's incandescent lamp patents, specifications for steam engines, and lamp orders. Other correspondence pertains to exhibits for the Paris Electrical Exhibition of 1881. Among the recipients are George F. Barker, George E. Gouraud, and Francis Upton. The front cover is marked "1881 Letters." The book contains 497 numbered pages and an index. Approximately 30 percent of the book has been selected.