This notebook covers the period February-March 1888. It was used primarily by James W. Gladstone for notes, tables, and calculations regarding fiber carbonization, condensers, \"thermo battery\"" experiments, and the bleaching of tobacco. There are also scattered notes by Arthur E. Kennelly. Inserted into the book are about 20 loose pages containing instructions from Edison to Gladstone, a note from Edison to John [Ott?] relating to Gladstone\'s work, and various notes by Gladstone and Kennelly. The spine is labeled \""56.\"" The pages are unnumbered, and the book has been used in both directions. Several pages have been removed from the book. Approximately 140 pages have been used."