This notebook contains no dated entries but was probably used between 1872 and 1874. It is entirely by Edison. The first 81 numbered pages list the parts of the universal printer and the machines and tools needed to make them. Pages 100-109 contain similar information for another unnamed instrument. On pages 274-290 are drawings of multiple telegraphy circuits, At the end of the volume, on pages 315-320 (in reverse order), is a description of the chemical telegraph, which may be a rough draft for publication. On pages 305-314 (in reverse order) is a draft for an elementary introduction to electricity and telegraphy to go with sets of simple telegraph apparatus for beginners. The cover is labeled "Universal - Private." The book contains 320 numbered pages. Courtesy of Thomas Edison National Historical Park.