This letterbook covers the period July 1907-May 1908. Most of the correspondence is by Edison, John F. Randolph, and Harry F. Miller. There are also some letters by Mina Miller Edison. Many of the items relate to Edison's progress on the concrete house and frequent renewals of notes for money advanced by Edison to the Edison Portland Cement Co. Also included are letters pertaining to Edison's work on his alkaline storage battery; the manufacture of batteries by Sigmund Bergmann in Berlin, Germany; the possible use of bismuth in the battery; and difficulties at the ore processing plant in the Dunderland region of Norway. In addition, there is correspondence pertaining to the impending shutdown and attempted sale of the Darby Mine in Ontario, Canada; a letter by Edison stating that he has "nothing to do with the reproduction of music by the National Phonograph Co."; and several letters regarding the suicide deaths of John F. Randolph, Edison's secretary, and William Simpkin, a draftsman for the Dunderland Iron Ore Co. Also included is a letter to the novelist Theodore Dreiser in which Harry F. Miller conveys Edison's permission for an interview. Among the items pertaining to family and personal matters are letters concerning a second mastoid operation on Edison's ear and his convalescence; his membership in clubs and societies; and the upkeep of his winter home at Fort Myers, Florida.
The label on the front cover contains the following notation: "Thos. A. Edison, Personal Letter Book, From - July 1st, 1907. To - May 29, 1908." There is an inscription on the spine with similar information. The spine is also stamped "10." The book contains 995 numbered pages and an index. Approximately 20 percent of the book has been selected.