Bur's sons killed Ymer, and in his blood the whole race of Yotuns drowned except one couple, from whom new races of Yotuns or giants descended. Bur's sons dragged the body of Ymer into the middle of Ginungagap. Out of the trunk of the body they made the earth and of his blood the sea. His bones became the mountains, and of his hair they made trees. From the skull they made the heavens, which they elevated high above the earth and decorated with sparks from Muspelheim. But his brain was scattered in the air and became clouds. Around the earth they let the deep waters flow, and on the distant shores the escaped Yotuns took up their abode in Yotunheim and in Utgard. For protection against them the kind gods made from Ymer's eyebrows the fortification Midgard as a defence for the inner earth. But from heaven to earth they suspended the quivering bridge called Bifrost, or the rainbow. The Yotun woman Night, black and dark as her race, met Delling (the Dawn) of the Æsir race, and with him became the mother of Day, who was bright and fair as his father. Odin placed mother and son in the heavens and bid them each in turn ride over the earth. Night rides ahead with her horse Hrimfaxe, from whose foaming bit the earth is every morning covered with dew. Day follows with his horse Skinfaxe, whose radiant mane spreads light and air over the earth. A great number of maggots were bred in Ymer's body, and they became gnomes or dwarfs, little beings whom the gods gave human sense and appearance. They lived within the mountains and were skilful metal-workers, but they could not endure the light of day. Four dwarfs, the East, West, North, and South, were placed by the gods to carry the arch of heaven. As yet there were no human beings on earth. Then, one day, the three gods, Odin, Hoener, and Lodur, were walking on the shore of the sea, where they found two trees, and from them they made the first man and the first woman, Ask and Embla (ash and elm). Odin gave them life, Hoener reason, Lodur blood and fair complexion. The gods gave them Midgard for a home, and from them the whole human race is descended. The ever green ash tree Ygdrasil is the finest of all trees. It shoots up from three roots. One of them is in the well Hvergelmer in Niflheim, and on this the dragon Nidhugger is gnawing. The other root is in Yotunheim, in the wise Yotun Mimer's fountain. One of Odin's eyes, which he pledged for a drink of the fountain, is kept here. Whoever drinks of this fountain becomes wise. The third root is in heaven, at the Urdar well, where the gods hold their Thing or court. To this place they ride daily over the bridge Bifrost. Here also the three Norns abide, the maidens Urd, Verdande, and Skuld (past, present, and future). They pour water from the well over the roots of the tree. The Norns distribute life and govern fate, and nothing can change their decision.