This notebook covers the period December 1892-November 1893. It contains transcriptions by Arthur E. Kennelly of material from the rough record books used by experimenters in the Galvanometer Room. There are notes, drawings, tables, and calculations regarding a variety of electrical experiments, including tests of meters, alternators, induction coils, transformers, batteries, and rheostats. In addition, there are extensive notes relating to motors for the phonograph, the kinetograph, and street cars and notes concerning replies by numerous central stations to inquiries from the Committee on Lightning Protection and the Committee on Grounding the Neutral of the Association of Edison Illuminating Companies. Also included is material pertaining to the technical and commercial development of the Niagara hydroelectric power system, conductor determinations, impedance and induction, and the electromagnetic properties of iron and steel, along with theoretical notes on physics, electricity, and mathematics. At the end of the book is a subject index; it appears at the beginning of the book in the digital edition. The front cover is marked "VII" and "1892-Dec 3rd 1893-Nov." The book contains 85 numbered pages. Some pages were removed before the book was paginated. Numerous graphs and other items have been pasted into the book. Courtesy of Thomas Edison National Historical Park.