 Well, here's what Mark Twain had to say about the use of dialect in the book. A number of dialects are used to whip the Missouri Negro dialect, the extremist form of the Backwoods Southwestern dialect, the ordinary Pike County dialect. The shadings have not been done in a haphazard fashion or by guesswork, but painstakingly in support of personal familiarity with those several forms of speech. Mm-hmm.