This notebook covers the period December 1887-January 1892. At the beginning of the book are notes and drawings by Edison, dated December 1887-January 1888, regarding experimental lamps. Most of the remaining pages were used by John Joseph Force to record results of lamp trials. There are also a few notes and drawings by Force relating to lamp experiments. The front cover is labeled \"J.J. Force Book ON[E?].\"" The spine is labeled \""42.\"" The pages are unnumbered. Approximately 60 pages have been used."