This book covers the periods July 1891-December 1892 and October 1895-January 1896. It contains a monthly breakdown of labor, material, and overhead costs among experimental projects and other laboratory accounts. The companies to which accounts were charged are sometimes indicated. The book consists of 18 numbered sheets. The front cover is stamped "Abstract of Expenses No. 7. Laboratory T. A. Edison. Orange, N.J." The characters "& 9" are inscribed immediately following the "7."
Blank sheet not selected: 18.
This book was microfilmed in sections at a reduction ratio of 17:1. Courtesy of Thomas Edison National Historical Park.