Boil, Another Vinegar Remedy for

"If taken at first a boil can be cured by dipping the finger in strong vinegar and holding on the boil until it stops smarting. Repeat three or four times then apply a little oil to the head of boil."

Source: Mother's Remedies: Over One Thousand Tried and Tested Remidies from Mothers of the United States and Canada, T. J. Ritter