PROM. _One of thine own descendants he shall be._ IO. _How? shall a child of mine deliver thee?_ PROM. _Ten generations hence, and three beside._ IO. _Now hard to read the prophecy becomes._[20] Io’s mind cannot take so great a leap forward; and Prometheus, resuming the course of her wanderings in Asia, gradually leads up to the climax of her story. Having crossed the strait, she is again to bend her steps eastward. Through the land of the Gorgons she must go, and of the Griffins, and of Phorcy’s daughters, the three hags with one eye and one tooth between them. On the golden shores of Pluto she will see an army of one-eyed horsemen, whom she must carefully avoid; and toiling onward still, she must follow the course of the river Ethiopia far up to its very source. Then, at Canopus, a town upon the shores of distant Nile, she will find rest. So is completed the tale of Io’s wanderings. And now, before Prometheus reveals the strangest thing of all, he would convince her that he is speaking truth indeed. So he recalls to her mind a marvel that had happened on her way thither, but which she had not spoken when she related her story. PROM. _To the Molossian plains when thou hadst come,... And to Dodona’s rock-ridge, to the seat And sacred oracle of Thesprotian Zeus, Famed for its marvel of the talking oaks, That with clear voice and nowise doubtfully Hailed thee (sounds this familiar to thine ears?) The glorious bride of Zeus in days to come._[20] The weird music of the oaks came back to her as the titan spoke, phrased intelligibly now. It had haunted all her journey, but confusedly, hinting at something she could not clearly understand, and dared not name. But in the words of Prometheus its meaning pealed. Becoming in that far Eastern country the bride of the ruler of Olympus, she would found a splendid race. From her the Danaans would spring, one root of that Hellenic people which should civilize the Western world. She would give a line of kings to the Argive throne. But greater and more blessed than all, from her should come the supreme Greek hero Heracles, destined to release this suffering titan from his misery. As she muses on the wonder of it, Prometheus takes up again the thread of his prophecy. In that rich land which borders on the Nile she may at last stay her weary feet. “_There shall the hand of Zeus, with soft caress Upon thee laid, restore thee to thy mind: And thou shalt bear, named of his fruitful touch, A son, swart Epaphus, whom all that land, By the broad Nile-stream watered, shall enrich...._“[20] From Io’s son Epaphus should descend, generations afterward, a princess.