This notebook was used by William A. Hayes, Newman Henry Holland, William De Mille Telfair, and an experimenter named Fehen during March 1918-July 1920 for notes on experimental work done for the military during and shortly after World War I, as well as other research pertaining to sound recording. The notes at the beginning of the book relate primarily to a sound ranging apparatus for artillery. The experimenters listened to artillery being fired at Morristown and Sandy Hook, New Jersey, then returned to the laboratory to make adjustments on the recording apparatus being used. Also included are experiments on a telescribe (a device for recording telephone messages) and a "transophone reproducer." Toward the middle of the book is a series of tests by Hayes on various transmitters, along with sound recording tests involving recording from a reproducer. The entries near the end of the book relate to tests of an electrical recording device using combinations of "Marconi Bulbs," "Navy Bulbs," and "Western Electric Bulbs." The notes indicate that the work was done under Edison's supervision; some entries include descriptions of Edison's comments. The flyleaf contains the notation "Daily Journal of Work at Morristown, Sandy Hook & Laboratory." The pages are unnumbered. Approximately 110 pages have been used. Courtesy of Thomas Edison National Historical Park.