Before 1991, critics largely believed that Twain stopped writing after Chapter 16 and set the manuscript aside. The assertion appears logical, for Cairo is, indeed, the original destination of Jim and Huck. If Huck and Jim make it to Cairo, they can head north up the Ohio River, and the story heads toward its conclusion. It is obvious that Twain was struggling with the novel's direction, but the 1991 discovery of the first half of the Huck Finn manuscript revealed that Twain had continued through Chapter 18 and then set aside the manuscript for two years.
Although Huck is distraught at the thought of losing Jim, he does play the horrible prank, which contrasts sharply with Jim's parental demeanor. Tom Sawyer, no doubt, would have been proud of Huck's creativity and imagination, but Huck realizes that he has done more than embarrass Jim; he has taken advantage of his trust and friendship. The elaborate joke wounds Jim, and Huck is not prepared for Jim's confession that his "heart wuz mos' broke bekase you wuz los', en I didn' k'yer no' mo' what become er me en de raf'." Jim's somber comment serves, in a sense, to break the heart of Huck, and readers realize, just as Huck does, that Jim would give his life for the young boy who has always been on the opposite side of societal laws.
