In The Adventures of Huckleberry Finn, what does Jim think happened to him as a result of the trick that Tom plays on him?

While Jim is sleeping, Tom hangs Jim's hat on a tree branch so Jim will be confused as to how it got there. Jim is highly superstitious and develops a story of being visited by witches who rode him around the world. All the other slaves are envious of Jim's experience, much to Tom's amusement.