"Sign of the beast/corna" in Roman times

[Tarbicus]

Most of us know this favourite gesture of metalheads, but it turns out to have more ancient origins.

The head of the family walked through the house with bare feet at dead of night, making the mystic sign with his first and fourth fingers extended, the other fingers being turned inwards and the thumb crossed over them, in case he might run against an unsubstantial spirit as he moved noiselessly along. This is the sign of "le corna," held to be infallible against the Evil Eye in modern Italy. After solemnly washing his hands, he places black beans in his mouth, and throws others over his shoulders, saying, "With these beans do I redeem me and mine." He repeats this ceremony nine times without looking round, and the spirits are thought to follow unseen and pick up the beans. Then he purifies himself once more and clashes brass, and bids the demons leave his house. When he has repeated nine times "Manes exite paterni," he looks round, and the ceremony is over, and the restless ghosts have been duly laid for a year.

From Greek and Roman Ghost Stories, by Lacey Collison-Morley, available as a text download here:
http://www.archive.org/details/greekandromangho17190gut