This letterbook covers the period December 1891-October 1895. Most of the correspondence is by Fred C. Devonald, storekeeper, and pertains to the ordering of supplies and equipment. These routine items have not been selected. There are also letters by Edison, William K. L. Dickson, Arthur E. Kennelly, and Harry F. Miller regarding various subjects, including ore milling and lamp tests. Most of the selected documents are by Dickson and concern his work on the kinetoscope and the development of lenses and film. The book contains 698 numbered pages. Pages 230-673 are blank. Approximately 15 percent of the documents have been selected.