Corns, Onion a Cure for

"Soak a small onion in vinegar four hours, then cut in two and bind on the corn at night. In the morning (if the onion has remained over the corn) the soreness will be gone and you can pick out the core. If not cured in first application repeat."

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