This letterbook covers the period June-August 1889. Most of the correspondence is by Edison, Alfred O. Tate, and Samuel Insull. Many of the letters relate to the manufacture of the phonograph and talking doll and to the promotion of the phonograph in Europe and Asia. There is also correspondence dealing with the operations of the Edison Phonograph Works and with production problems at the Edison Lamp Co. Other letters pertain to mining and ore milling, Edison's phonoplex system, and his exhibit at the Paris Exposition. Some of the documents concern Edison's experimental work on electric lighting and the purchase of property in Silver Lake, N.J. Of particular interest are two long letters from Insull to Tate, which were written while Tate was in Europe. The book contains 507 numbered pages and an index. Approximately 40 percent of the book has been selected.