From Egyptian Secrets of Albertus Magnus, Joseph H. Peterson edition:
What Black Snails are Good for.
They exterminate warts and corns on hands and feet, heal ruptures and other injuries. They must be prepared thus: Put all the snails together in a pot, throw much salt therein, bury the pot for nine days, after this distil the matter in a glass in the sun.
The grimoire Egyptian Secrets of Albertus Magnus lists this spell.