Adventures of Huckleberry Finn
Mark Twain's raft, and the river it goes down.
246 cryptograms drawn from it, every one by Mark Twain.
How hard they are
100 easy, 93 medium and 53 hard, graded by the model described in our guide to solving cryptograms.
They average 70.6 letters over 19.1 distinct ones, with 4.1 letters appearing exactly once.