" In parts of the country you will come across superstitious practices, such as lowering a infant with whooping cough into a cesspit and holding him in the corrupt air. Snakeskin is widely thought of as a remedy for a number of diseases, and, according to William Horman, so is “the unwashed wool that grows between the hind legs of a black sheep.” I doubt that you will find anyone who can explain the medical reasoning behind that last one. It makes the theory of the humors look reassuringly sophisticated. "