But Perseus’ adventures were not over.  As he flew on by the Lybian coast he heard a sound of wailing, and beheld a beautiful maiden chained by her hands and feet to a rock.  He asked what had led her to this sad plight, and she answered that she was Andromeda, the daughter of Cepheus and Cassiopeia, king and queen of Ethiopia, and that her mother had foolishly boasted that she was fairer than the Nereids, the fifty nymphs who are the spirits of the waves.  Neptune was so much displeased that he sent a flood to overflow the land, and a sea-monster to devour the people and cattle.  In an oasis or isle of fertility in the middle of the Lybian desert was a temple of Jupiter, there called Ammon, and the Ethiopians had sent there to ask what to do.  The oracle replied that the evil should cease if Andromeda were given up to the monster.  Cepheus had been obliged to yield her up because of the outcries of the people, and here she was waiting to be devoured.  Perseus, of course, was ready.  He heard the monster coming, bade Andromeda close her eyes, and then held up the Gorgon’s head.  In an instant her foe had become a rock, and he cleft the maiden’s chains, brought her back to her father and mother, who gave her to him in marriage, and made a great feast; but here a former lover of hers insulted them both so much, that Perseus was forced to show him the Gorgon’s face, and turn him into stone.