Sæmundr Sigfússon

“ These dwarfs are called East, West, North, and South. They afterwards took the wandering sparks and red hot flakes that had been cast out of Muspellheim, and placed them in the heavens, both above and below, to give light unto the world, and assigned to every other errant coruscation a prescribed locality and motion. ”

“ But how is the earth fashioned?"
"It is round without," replied Har, "and encircled by the deep ocean, the outward shores of which were assigned for a dwelling to the race of giants. But within, round about the earth, they (the sons of Bor) raised a bulwark against turbulent giants, employing for this structure Ymir's eyebrows. To this bulwark they gave the name of Midgard [1] . They afterwards tossed Ymir's brains into the air, and they became the clouds, for thus we find it recorded.
"Of Ymir's flesh was formed the earth ”