This notebook was used by John A. Hanley during February-September 1919 for experimental notes on submarine detection. Most of the entries pertain to tests conducted at sea on detection equipment. The book ends with the note "Burns to do this. I am to continue on Storage Battery job." The notes indicate that Hanley was reporting to Edison through William H. Meadowcroft. The front cover is labeled "Experiments. Edison Submarine Detector. No - 2. From, Feb. 14-19, To." Numerous loose pages relating to these experiments have been inserted into the book. The pages are unnumbered. Approximately 125 pages have been used. Courtesy of Thomas Edison National Historical Park.