This volume covers the period June-December 1878, with one additional entry for November, 1876 and a few for 1879. The notes and drawings are by Edison, Charles Batchelor, Charles P. Edison, and John Kruesi, and they relate entirely to the telephone. Many were witnessed by members of the laboratory staff and notarized by Stockton L. Griffin. The volume consists of 123 numbered, unbound pages.
Several items from Vol. 18 were published in The Papers of Thomas A. Edison, Vol. 4. The images constituting these documents have been arranged in their proper sequence.