This notebook was used in February-March 1918 by William A. Hayes and William Deans for notes pertaining to Edison's work for the U.S. Navy during World War I. There are numerous notations by Edison, many of which are pasted into the book. The entries by Hayes at the experimenters. They describe sound detection experiments based on new instructions from Edison, and some include rough drawings by Edison. The inside front flyleaf is inscribed "Records made for Mr. Edison at Key West" and "W. A. Hayes." The book contains approximately 40 unnumbered pages followed by 52 numbered pages, some of which are blank. Several loose pages of drawings and mathematical equations have been inserted into the book.