This letterbook covers the period February-March 1890. Most of the letters are by Alfred O. Tate. There is also correspondence by Edison, Charles Batchelor, and John F. Randolph. Many of the letters relate to the manufacture and marketing of the phonograph and talking doll. Included are letters about the coin-operated phonograph, the operations of the Edison Phonograph Works and the Edison Phonograph Toy Manufacturing Co., the demonstration of the phonograph in Russia, and the presentation of phonographs to William II, Emperor of Germany, and other foreign dignitaries. Other letters pertain to electric lighting, the phonoplex system, mining, and ore milling. There are also several long letters written to Edison while he was inspecting mines near Charlotte, North Carolina. Beginning on page 330 is a four-page list of experimental accounts from January to March 1890. The book contains 500 numbered pages and an index. Approximately 40 percent of the book has been selected.