This notebook was used by Edison on December 4, 1912. The entries pertain to the electroplating processes involved in disc record manufacture. Most of the notes relate to problems observed during electrolysis, including dirt and gas bubbles adhering to the plated face of "master" and "submaster" molds. Also included are notes on modifications to the electroplating tank. The pages are unnumbered. Only five pages have been used. Courtesy of Thomas Edison National Historical Park.