Then Gunnar sprang to earth, and stamped with impatience, for he thought it shame to go afoot into the presence of the maid. Presently he remembered that his witch-mother had given him a magic potion which would enable a man to take the face and form of another at will. So he proposed that Sigurd should take his appearance and win Brunhild for him by proxy, for he knew that Greyfell would dare anything with his beloved master astride his back.

Remembering naught, Sigurd eagerly accepted the mission, and when he had drunk of the potion prepared by Gunnar he leaped again upon the back of Greyfell, who sprang at once into the heart of the fire.

Then the flames roared with a thunderous sound, and shot up high into the sky; but next moment they died away into a heap of grey ashes, and Sigurd, unharmed, entered the hall where Brunhild sat and waited for her faithless lover.

As he entered she started up with a cry of joy, which quickly died away when, in place of Sigurd's fair hair and bright blue eyes, she saw the dark locks and flashing black eyes of Gunnar.

"What man art thou?" she asked.

"Gunnar am I called," said Sigurd, "and through the flames have I ridden to woo thee for my bride."

But she looked sadly at the floor and said: "Methought none but Sigurd the Volsung could have dared those awful flames."

Then Sigurd thought to entice the maiden. "Much gold shall be thine," said he, "if thou wilt marry Gunnar the Niblung."

But she said: "Talk not to me of gold. All-Father Odin promised me a hero-husband, and I, a warrior-maiden, will marry no silken knight for gold."

Now Brunhild had bound herself by a solemn pledge to marry him who should ride through the fire, so in the end she was obliged to submit to her wooer's will; wherefore she took off the ring from Andvari's hoard that Sigurd had placed upon her finger, and gave it to him, with her promise to appear at the court of the Niblungs in ten days' time. Sigurd gave her another ring in exchange, and then rejoined Gunnar, with whom he rode back home, after having taken back his own form and likeness.