Circe. Engraving by W. Sharp, 1780, after J. Boydell after D. Zampieri, il Domenichino.

In Homer's "Odyssey" (Book 10), Odysseus and his companions land on Circe's island. Circe was a witch, who gave travellers a magic potion which turn them into animals. Some of Odysseus's companions fell into this trap, but not Odysseus who had been forewarned by Hermes