Brewer's: Hair of the Dog that Bit You
(A). Similia similibus curantur. In Scotland it is a popular belief that a few hairs of the dog that bit you applied to the wound will prevent evil consequences. Applied to drinks, it means, if overnight you have indulged too freely, take a glass of the same wine next morning to soothe the nerves. “If this dog do you bite, soon as out of your bed, take a hair of the tail in the morning.”
Take the hair, it's well written, Of the dog by which you're bitten; Work off one wine by his brother, And one labour with another ... Cook with cook, and strife with strife: Business with business, wife with wife.
Athenæus (ascribed to Aristophanes).
There was a man, and he was wise, Who fell into a bramble-bus And scratched out both his eyes; And when his eyes were out, he then Jumped into the bramble-bush And scratched them in again.