Found in a Day By Day entry for July 18, 1902:  Sam wrote a letter to an 
unidentified person.

York Harbor, July 18.—Dear Sir.—I thank you very much. That book is even 
more flatteringly isolated than was one a stranger wrote me about, years 
ago, from the Far West. He said: ‘In a 400-mile horseback ride through 
the cattle domain I found but a solitary two books among the 
cowboys—“The Innocents Abroad” and the Bible.’ And he added, ‘The Bible 
was in good condition.’—Very truly yours, Mark Twain.

That "stranger" was Jack Van Nostrand, a fellow traveler on the Quaker 
City. He had written to Sam in 1875. “Jack Van Nostrand to SLC, 29 June 
1875 · Manitou, Colo., (UCLC 32191).”

-- 
/*Unaffiliated Geographer and Twain aficionado*/

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