In chapter 6, Huckleberry asserts that dead cats cure warts. However, Tom insists that spunk-water (the rain-water collected in an old rotten stump) is better at curing warts. He even proves it by telling the story of a man who did it with success. Huckleberry argues that it has to be done a certain way, at midnight, and gives the exact steps that must be taken as well as the magic words to say. Tom also explains how to remove warts with a bean and Huck returns by explaining how to use the dead cat. Huck also explains how witches cast spells - by saying the Lord's prayer backwards. He insists that one cast a spell on his Pap once.
In chapter 8, Tom is disappointed that one of his superstitions had failed. His marble, which he had recited incantations over, hadn't produced his other lost marbles. So instead, he speaks magic words to get a little black bug to come out, who, by not telling him anything, indicates that a witch made his spell not work. Then he tries another superstition by trying to get the marble to locate its lost "brother". His third try is successful.