This notebook covers the period March 1875-November 1876. The book was begun by Charles P. Edison, who inscribed the first page: "C.P. Edison Newark New Jersey March 10th 1875." The only other dated entry in the first part of the book is for October 5, 1876. Most of the material relates to telegraph apparatus. Included are circuit diagrams, drawings of instruments (especially printers, sounders, and keys), and calculations. There are also cartoons and doodles.
The second part of the book contains signed drawings by Thomas A. Edison, along with a few by James Adams. The drawings relate to multiple and acoustic telegraphy, and the few dated ones fall between September and November 1876. In addition to the drawings, there are clippings and advertisements about electrical apparatus and steam engines, and an obituary of Marshall Lefferts.
The book contains 157 numbered pages, preceded by seven unnumbered leaves. The number 151 has not been used. Many leaves were apparently torn out before the pages were numbered. Courtesy of Thomas Edison National Historical Park.