This notebook was used by William Walter Dinwiddie during March-April 1918 for notes on efforts to improve the surface quality of Edison disc records. The entries pertain primarily to a sequence of experiments numbered from 1897E through 1975E. Most involve experimental lots of record blanks constructed by different methods, prepared with various varnish compounds and methods of varnishing, or printed according to different schedules of heat and pressure application. The notes generally take the form of instructions describing the experimental records wanted, accompanied by evaluations of the test records produced. One entry mentions work done during the "strike of blanks makers" on March 26-27. Several pages of additional notes by Archie D. Hoffman, consisting of caliper measurements for experimental record blanks, have been pasted into the book. The notes indicate that some of the caliper measurements were performed by an experimenter named Haviland and that Dinwiddie also received assistance from Peter C. Christensen and John McMullen. Among the unselected loose items inserted into the book are several cursory notes by R. Voorhis on celluloid records printed in May 1918, as well as notes by Dinwiddie, C. Hiles, and Charles G. Kircher. The front and back covers are labeled "26." The pages are unnumbered. Approximately 120 pages have been used. Courtesy of Thomas Edison National Historical Park.