The first entry in this notebook is dated June 19, 1903, but the correct year is probably 1905 since related entries are dated June and July 1905. There is also a marginal notation dated January 1906. Most entries are by Edison. The book contains notes and drawings regarding storage battery experiments, along with a one-page entry pertaining to ore milling. The beginning of the book contains cell tests, numbered from 646 through 766, using acidic, rather than alkaline, electrolytic solutions. At the end of the book is a series of tube tests, numbered from 1 through 89, dealing with the packing and arrangement of nickel flake in the cylindrical tubes of the storage battery. These tests are continued in a set of thirty-six numbered notebooks designated as "Mix Books" or "Tube Books" (see Notebooks by Edison and Other Experimenters, Group 4: Tube Books, Nos. 1-36). The front cover is labeled "Storage Battery Important Data." The pages are unnumbered. Approximately 180 pages have been used.