This notebook was used during the period July-August 1912 and also in December 1912. All entries are by Edison. The entries from the summer of 1912 pertain primarily to the transfer and pressing processes involved in disc record manufacture. They describe experiments with various methods of preparing Condensite varnish surfaces and culminate in a list of eight steps in the process of pressing disc records. Edison's notes indicate that Edward L. Aiken, Jonas Walter Aylsworth, Harry R. Grimes, Sherwood T. (Sam) Moore, and Frederick P. Ott assisted him in some instances. There is one reference to notes entered into "Book B," probably N-12-07-28. Also included is a series of entries on "instrument tests" that describe the sound quality and volume of recordings made with individual string and wind instruments. Entries from December relate to the electroplating involved in disc record manufacture and include experiments on plating molds with electrolytic deposits of nickel, gold, and copper, as well as notes on the structure of the plating tank. There is also a comment on Edison's work habits. Inserted into the book are three related notes by Edison, including one from January 14, 1913, addressed to Ott. The front cover is labeled "A." The pages are unnumbered. Approximately 65 pages have been used. Courtesy of Thomas Edison National Historical Park.