This copy book contains three caveats relating to multiple telegraphy. They are signed by Edison and are in his hand. The first is dated January 16, 1874; the second is for January 20, 1876; and the third is undated. The ink on many of the pages is very faint. Pages 112-118 contain faint copies of cash accounts for March 1875 and January 1876.
This book was also used for tests of Edison's duplicating ink. These begin on page 133 and continue, in lessening degrees of legibility, until page 155, with additional tests on pages 400, 407, and 487-501. The remaining pages are either blank or stained with ink. Many pages have been torn out.
The book contains 501 numbered pages, preceded by a nine-page index with no entries.
Pages selected: 1-90, 133, 139, 400, 407, 499. Courtesy of Thomas Edison National Historical Park.