This notebook was used by William Walter Dinwiddie, Archie D. Hoffman, and possibly other experimenters during July-August 1917 for notes on efforts to improve Edison disc records. There are occasional comments by Edison on the work performed. The entries pertain primarily to a sequence of experiments numbered from 1657E through 1749E. Included are tests of experimental lots of record blanks constructed by different methods or prepared with different ingredients. The entries generally consist of instructions by Dinwiddie or Hoffman describing the experimental records wanted, accompanied by evaluations of the test records based on their durability, thickness, and edging. One entry toward the end of the book gives a "Schedule of Operations" involved in pressing records. The front is labeled "Disc Record" and "23"; the back cover is labeled "23." The pages are unnumbered. Approximately 200 pages have been used. Courtesy of Thomas Edison National Historical Park.