D'Aulaires Book of Greek Myths

In life, the Gorgon Medusa had the ability to stop anyone who looked at her in their tracks: They immediately turned to stone. When the king sent Perseus on the quest to bring him her head, he believed that Perseus would die in the attempt. No one who went after Medusa had ever returned. With the help of the gods’ favor, however, Perseus did the impossible: He killed Medusa without looking directly at her and carried away her head, which retains the power Medusa had in life. Anyone who sees her head is turned to stone.

Perseus drew on this power by pulling out the head to stop Andromeda’s cowardly suitors, who returned to claim her only after Perseus had dispatched the monster. When he discovered that the king had attempted to carry off his mother after he left on his quest, he used the head to turn the king and his court to stone. It is at this moment that Perseus deviated from the self-destructive pattern typical of heroes, for rather than continue to draw on its power, he relinquished it to Athena, entrusting its immortal power to another immortal.

The head of Medusa in the