The following sources furnished the documentary basis for this itinerary: Clemens’s letters to the San Francisco Alta California (beginning with SLC 1867); N&J1, 329–452; The Innocents Abroad (SLC 1869); journals kept by William R. Denny, Charles C. Duncan (the most reliable source for the ship’s arrival and departure times), Charles J. Langdon, Benjamin B. Nesbit, and Emily A. Severance (the above documents, already cited in the notes, are fully described in References); and newspaper letters written by Moses S. Beach, William R. Denny, Charles C. Duncan and Emily A. Severance, Mary Mason Fairbanks, Abraham R. Jackson, William E. James, Julius Moulton, and Julia Newell. We are grateful to Leon T. Dickinson, who in 1969 provided the Mark Twain Papers with copies of these newspaper letters, most of which he discovered. A full record is given below of all the known letters from each newspaper correspondent; explicit case-by-case citation of all supporting (or conflicting) evidence has been deemed impractical.

The hours of departure and arrival given in the itinerary are approximate. When the time of day was recorded differently in two or more sources, either the most probable time or a reasonable average was adopted. Similarly, when the date was recorded differently, the most likely was chosen. Whenever possible, place names are given in English (“Leghorn” rather than “Livorno,” for example). Spelling authorities were, in descending order, the National Geographic Atlas, Webster’s New Geographical Dictionary, and Murray.