This notebook was used in 1920-1921 by James Toy for notes on experiments to improve the quality of Blue Amberol cylinder records. These experiments, which were carried out under Edison's directions, illustrate the inventor's commitment to the cylinder format as late as 1920-1921. The experiments involved a variety of materials, including rubber cement, linseed oil, and collodion. A note by Toy bearing a response from Edison, as well as some brief instructions by Edison, have been taped into the book. The front cover is labeled "706-x-1." The book contains 139 numbered pages followed by approximately 50 unnumbered pages.
Only the two pages with Edison notations have been selected. Courtesy of Thomas Edison National Historical Park.