Wherever Orpheus wandered with his lyre, no one had the will to forbid him entrance; and at length he found unguarded that very cave that leads to the Underworld, where Pluto rules the spirits of the dead. He went down without fear. The fire in his living heart found him a way through the gloom of that place. He crossed the Styx, the black river that the Gods name as their most sacred oath. Charon, the harsh old ferryman who takes the shades across, forgot to ask of him the coin that every soul must pay. For Orpheus sang. There in the Underworld the song of Apollo would not have moved the poor ghosts so much. It would have amazed them, like a star far off that no one understands. But here was a human singer, and he sang of things that grow in every human heart, youth and love and death, the sweetness of the Earth, and the bitterness of losing aught that is dear to us. Now the dead, when they go to the Underworld, drink of the pool of Lethe; and forgetfulness of all that has passed comes upon them like a sleep, and they lose their longing for the world, they lose their memory of pain, and live content with that cool twilight. But not the pool of Lethe itself could withstand the song of Orpheus; and in the hearts of the shades all the old dreams awoke wondering. They remembered once more the life of men on earth, the glory of the sun and moon, the sweetness of new grass, the warmth of their homes, all the old joy and grief that they had known. And they wept. Even the Furies were moved to pity. Those, too, who were suffering punishment for evil deeds ceased to be tormented for themselves, and grieved only for the innocent Orpheus who had lost Eurydice. Sisyphus, that fraudulent king (who is doomed to roll a monstrous boulder uphill forever), stopped to listen. The daughters of Danaus left off their task of drawing water in a sieve. Tantalus forgot hunger and thirst, though before his eyes hung magical fruits that were wont to vanish out of his grasp, and just beyond reach bubbled the water that was a torment to his ears; he did not hear it while Orpheus sang. So, among a crowd of eager ghosts, Orpheus came, singing with all his heart, before the king and queen of Hades. And the queen Proserpina wept as she listened and grew homesick, remembering the fields of Enna and the growing of the wheat, and her own beautiful mother, Demeter. Then Pluto gave way. They called Eurydice and she came, like a young guest unused to the darkness of the Underworld. She was to return with Orpheus, but on one condition. If he turned to look at her once before they reached the upper air, he must lose her again and go back to the world alone.