I have recently acquired the two editions of the Mark Twain Journal
pertaining to The Innocents Abroad and through these I have been made
aware of this astounding relationship - Fairbanks and Clemens.  I had no
real conception of just how much Clemens disliked many of his fellow
passengers.  I've read The Innocents Abroad more than a couple times and
have recorded a reading.  I had thought Mark Twain was amused by their
religious pronouncements but truly upset only by their souvenir hunting
and the cruelty they displayed to their animals in order to avoid
traveling on the sabbath.  His true feelings seem to be more fully
expressed in two letters to Mary Mason Fairbanks on the 2nd and 12th of
December 1867.  His promises to her must have been of paramount
importance to him to tone down his letters and the book to the degree he
did.