This pocket notebook was used by Edison. The only dated entry is for April 12, 1889, and concerns incandescent and arc lamp designs. Preceding that entry is a series of numbered notes on phonograph cylinder experiments. The book was also used from the back forward for notes on chemical reagents and a list of elements and densities. The pages are unnumbered. Approximately 50 pages have been used.
Note: The images in this pocket notebook are quite small. They can be enlarged to a more readable size by using the "image zoom" feature of the Firefox browser. Click here to download the Firefox "image zoom" add-on. Right-click on the image to enlarge. Courtesy of Thomas Edison National Historical Park.