This notebook was used during August 1915-July 1916 by Absalom M. Kennedy as a record of experiments with phonograph recorders. Each entry contains the number of the recorder, ranging from 52 through 134, along with comments about components such as head, diaphragm, arm, and sapphire needle and the type of disc used. Edison's opinions about the quality and loudness of the recordings are occasionally mentioned in Kennedy's notes. Inserted into the book is a communication from Kennedy requesting permission to teach employee E. Rowland Dawson how to make stretched recorders, along with Edison's affirmative response. The front cover is labeled "Record of Recorders." The pages are unnumbered, and at least one page has been removed from the book. Approximately 75 pages have been used. Courtesy of Thomas Edison National Historical Park.