This letterbook covers the period January-February 1890. Most of the correspondence is by Edison and Alfred O. Tate. Many of the documents relate to the manufacture and marketing of the phonograph and talking doll. Included are letters about the coin-operated phonograph, a set of directions for using the Edison water-motor phonograph, and a phonograph test report. There is also correspondence pertaining to ore milling and the purchase of mining properties. Other letters concern Edison's personal and business finances and his trip to North Carolina. In addition, there is a 3-page letter containing a subject-classification list for the filing of Edison's incoming correspondence. The front cover is labeled "Indexed T. A. Edison General Letter Book. Laboratory." The book contains 497 numbered pages and an index. Approximately 40 percent of the book has been selected.