This notebook covers the period June-November 1889. Most of the book was used by John V. N. Dorr for notes on ore analyses in the chemical laboratory. There are also entries by Dorr regarding phonograph battery experiments and notes from Reginald Fessenden to Dorr relating to ore milling work and the cleaning and physical arrangement of the laboratory. The front cover is labeled \"John V. N. Dorr #553.\"" The book contains 79 numbered pages followed by approximately 100 unnumbered pages.
Only the material by Fessenden and the notes on phonograph battery experiments have been selected."