This notebook covers the period September-October 1881. All of the entries are by Francis Jehl. The book contains notes, calculations, and drawings relating to various electrical tests. Included are tests of meters, dynamos, cable insulation, batteries, wire conductivity, and fuses. There are two labels on the front cover marked "General" and "Francis Jehl." The book contains 280 numbered pages.
Blank pages: 50-257, 262-280. Courtesy of Thomas Edison National Historical Park.