This notebook was used by Edison during August-September 1920. The entries pertain to the plating processes involved in the manufacture of disc records. The notes describe efforts to improve the surface of disc record molds by polishing the copper masters with a rouge mixture and the nickel-faced females with an emery paste. The entries also report attempts to improve the plating by changing the acid and copper sulfate content, by improving the filtering operation, by adjusting the plating schedule, and by applying a coat or rubber solution to the back of the mold to prevent copper and nickel deposits. Inserted into the book is a note from Paul B. Kasakove to Edison describing a mold plated with a copper shot anode. The cover is labeled "T-A-E No 4 Plating Disc." The pages are unnumbered. Approximately 75 pages have been used. Courtesy of Thomas Edison National Historical Park.