Two more of the Argonauts were Castor and Pollux, the twin sons of Leda, queen of Sparta. She had also two daughters, named Helen and Clytemnestra, and Helen was growing into the most beautiful woman in the world. These children, in the fable, had been hatched from two huge swans’ eggs; Castor and Clytemnestra were in one egg, and Pollux and Helen in the other. Castor and Pollux were the most loving of brothers, and while Castor was famous for horsemanship, Pollux was the best of boxers. They, too, had been pupils of Chiron; so was Peleus of Ægina, who had wooed Thetis, one of the fifty Nereids, or sea-nymphs, though she changed herself into all sorts of forms when he caught her first—fire, water, a serpent, and a lioness; but he held her fast through all, and at last she listened to him, and all the gods and goddesses had come to the wedding feast. They had one son, named Achilles, whom Thetis had tried to make immortal after Ceres’ fashion, by putting him on the fire at night; but, like Triptolemus’ mother, Peleus had cried out and spoilt the spell. Then she took the boy to the river Styx, and bathed him there, so that he became invulnerable all over, except in the heel by which she held him. The child was now in Chiron’s cave, being fed with the marrow of lions and bears, to make him strong and brave. One more Argonaut must be mentioned, namely, the minstrel Orpheus. He was the son of the muse Calliope, and was looked on as the first of the many glorious singers of Greece, who taught the noblest and best lessons. His music, when he played on the lyre, was so sweet, that all the animals, both fierce and gentle, came round to hear it; and not only these, but even the trees and rocks gathered round, entranced by the sweetness. All these and more, to the number of fifty, joined Jason in his enterprise. The Argo, the ship which bore them, had fifty oars, and in the keel was a piece of wood from the great oak of Dodona, which could speak for the oracles. When all was ready, Jason stood on the poop, and poured forth a libation from a golden cup, praying aloud to Jupiter, to the Winds, the Days, the Nights, and to Fate to grant them a favourable voyage. Old Chiron came down from his hills to cheer them, and pray for their return; and as the oars kept measured time, Orpheus struck his lyre in tune with their splash in the blue waters. They had many adventures. After passing the Hellespont, they found in the Propontis, which we call the Sea of Marmora, an islet called the Bears’ Hill, inhabited by giants with six arms, whom they slew. In Mysia a youth named Hylas went ashore to fetch water, but was caught by the nymphs of the stream and taken captive. Hercules, hearing his cry, went in search of him, and, as neither returned, the Argo sailed without them. No more was heard of Hylas, but Hercules went back to Argos.