This notebook was used by Edison, Archie D. Hoffman, and possibly other experimenters during July-August 1917 for notes on efforts to improve the surface quality of Edison disc records. The entries pertain primarily to a sequence of experiments numbered from 1750E through1781E. Most involve experimental lots of record blanks constructed by different methods or prepared with different ingredients. The notes often take the form of instructions to Hoffman, Charles Dally, Frederick P. Ott, or other unspecified employees and include evaluations of the records produced. The entries toward the end of the book summarize the results obtained by varying the amounts of pressure, indicating an increase in durability in the records produced at the end of July. Inserted into the book are several loose notes by Edison and Hoffman. The front cover is labeled "24." The pages are unnumbered. Approximately 50 pages have been used. Courtesy of Thomas Edison National Historical Park.