The dated entries in this notebook, which has been used in both directions, cover the periods March and October 1886. The technical entries are by Edison and relate to the phonoplex, a hearing aid, lamp filaments, and kerosene lamps. There are also notes by Edison to his patent attorney, Richard N. Dyer, regarding an interference with John T. Sprague. In addition, there are undated entries in Mina Miller Edison's hand (images 33-36) pertaining to expenses incurred during her honeymoon in Florida in March 1886 and her return trip to Akron with Edison and her parents, Lewis and Mary Valinda Miller. The entries in the middle of the book (images 12-19), which contain references to "Madeleine," "diapers," and "baby basket," may have been made in connection with Edisons' impending trip to Europe in 1889, during which Madeleine stayed with the Miller family in Akron. The front cover is stamped "Address." The book is unpaginated; approximately 60 pages have been used. Numerous pages have been torn out of the book.