Then he unbuckled a strap and a girdle of leather and gave his huge sword to his son, saying: "This that has brought our family down the ages unto this day shall surely guard you always upon your journey, even though you fare beyond the fields we know." And the young man took it though he knew that no such sword could avail him. Near the Castle of Erl there lived a lonely witch, on high land near the thunder, which used to roll in Summer along the hills. There she dwelt by herself in a narrow cottage of thatch and roamed the high fields alone to gather the thunderbolts. Of these thunderbolts, that had no earthly forging, were made, with suitable runes, such weapons as had to parry unearthly dangers. And alone would roam this witch at certain tides of Spring, taking the form of a young girl in her beauty, singing among tall flowers in gardens of Erl. She would go at the hour when hawk-moths first pass from bell to bell. And of those few that had seen her was this son of the Lord of Erl. And though it was calamity to love her, though it rapt men's thoughts away from all things true, yet the beauty of the form that was not hers had lured him to gaze at her with deep young eyes, till--whether flattery or pity moved her, who knows that is mortal?--she spared him whom her arts might well have destroyed and, changing instantly in that garden there, showed him the rightful form of a deadly witch. And even then his eyes did not at once forsake her, and in the moments that his glance still lingered upon that withered shape that haunted the hollyhocks he had her gratitude that may not be bought, nor won by any charms that Christians know. And she had beckoned to him and he had followed, and learned from her on her thunder-haunted hill that on the day of need a sword might be made of metals not sprung from Earth, with runes along it that would waft away, certainly any thrust of earthly sword, and except for three master-runes could thwart the weapons of Elfland. As he took his father's sword the young man thought of the witch. It was scarcely dark in the valley when he left the Castle of Erl, and went so swiftly up the witch's hill that a dim light lingered yet on its highest heaths when he came near the cottage of the one that he sought, and found her burning bones at a fire in the open. To her he said that the day of his need was come. And she bade him gather thunderbolts in her garden, in the soft earth under her cabbages. And there with eyes that saw every minute more dimly, and fingers that grew accustomed to the thunderbolts' curious surfaces, he found before darkness came down on him seventeen: and these he heaped into a silken kerchief and carried back to the witch.