[The following pocket notebook was originally published in the microfilm edition of Thomas A. Edison Papers, Part I (1850-1878). Additional pages were subsequently discovered, and the book was re-filmed in its entirety in the Supplement Series of Thomas A. Edison Papers, Part III (1887-1898).

This undated pocket notebook is one of three books that Edison took with him to England in the spring of 1873. The entries deal primarily with experiments on cable and automatic telegraphy, including Edison's Greenwich cable tests. Several pages have been torn from the book. Approximately 80 pages have been used.