The two entries in this notebook are dated February 7, 1908, and February 7, 1909. The first entry is probably misdated. The book contains notes by Edison regarding tests of various metals and minerals as possible replacements for sapphire in phonograph reproducers. The notebook is similar to N-09-02-24 and was probably used at Edison's laboratory in Fort Myers, Florida. The pages are unnumbered. Only 3 pages have been used.
Courtesy of Thomas Edison National Historical Park.