“I know you,” Prometheus said. “You are Io, once a fair and happy maiden dwelling in Argos, doomed by Jupiter and his jealous queen to wander over the earth in this guise. Go southward and then west until you come to the great river Nile. There you shall again become a maiden, fairer than ever before, and shall marry the king of that country. And from your race shall spring the hero who will break my chains and set me free.”
Centuries passed and then a great hero, Hercules, came to the Caucasus Mountains. He climbed the rugged peak, slew the fierce eagle, and with mighty blows broke the chains that bound the friend of man.
THE LABORS OF HERCULES
Before the birth of Hercules Jupiter had explained in the council of the gods that the first descendant of Perseus should be the ruler of all the others of his race. This honor was intended for the son of Perseus and Alcmene; but Juno was jealous and brought it about that Eurystheus, who was also a descendant of Perseus, should be born before Theseus. So Eurystheus became king in Mycene, and the later-born Hercules remained inferior to him.
Now Eurystheus watched with anxiety the rising fame of his young relative, and called his subject to him, demanding that he carry through certain great tasks or labors. When Hercules did not immediately obey, Jupiter himself sent word to him that he should fulfill his service to the King of Greece.
Nevertheless the hero son of a god could not make up his mind easily to render service to a mere mortal. So he traveled to Delhi and questioned the oracle as to what he should do. This was the answer:
The overlordship of Eurystheus will be qualified on condition that Hercules perform ten labors that Eurystheus shall assign him. When this is done, Hercules shall be numbered among the immortal gods.