This notebook covers the period May-June 1884. Most of the entries are by Edison. Included are notes and drawings relating to filament experiments to be conducted by several assistants, calculations about the cost of mining operations, a list of articles in the Philosophical Transactions, and a list of scientific equipment companies and their addresses. There are also a few drawings by an unknown assistant that appear to be for a furnace and flue design. The cover is labeled "C. H. Campbell." The book contains 280 numbered pages followed by 2 unnumbered pages.