This notebook covers the period April-July 1904. It contains notes and drawings by Edison and an unidentified experimenter regarding storage battery experiments. Most of the entries relate to problems with the foaming action of the potassium hydroxide solution and to attempts to identify a compound that would retard the foaming. There are also items pertaining to improved techniques for loading iron powder in the cell grids. Inserted into the book are approximately 20 pages of notes concerning chemicals tested for foaming. The pages are unnumbered. Approximately 50 pages have been used.