The mythic poems of the 'Edda,' taken together, give us a tolerably complete picture of the Northern mythology in the Viking Age; although some of them were not written until after the introduction of Christianity, and are therefore open to the imputation of having been to a greater or less extent affected by its teachings. The oldest poems of the collection are mythical in character. In some of them a particular god is the principal figure. Several of them, like the 'Vafthrudnismal,' the 'Grimnismal,' 'Baldrs Draumar,' and the 'Harbardsljod,' in this way are particularly devoted to Odin, whose supremacy they show over all other beings, and whose part they describe in the government of the universe; in others, like the 'Hymiskvida,' the 'Thrymskvida,' and the 'Alvismal,' Thor occupies the prominent part in his strife with the giants; single ones have other gods as their principal actors, like Skirnir, the messenger of Frey, in the 'Skirnismal,' Loki, the god of destruction, in the 'Lokasenna,' or Heimdall, the guardian of the rainbow bridge which stretched from heaven to earth, in the 'Rigsthula.' A few of them are both mythic and heroic at the same time, like the 'Lay of Voelund,' which tells of the fearful revenge of the mythical smith upon the Swedish king; or the 'Song of Grotti,' the magical mill, which ground what was wished, first peace and gold for its owner, King Frodi of Denmark, but later so much salt on the ship of Mysing, who had conquered the king and taken it away, that all together sunk into the sea, which henceforth was salt. By far the greater of the mythic lays is the long but fragmentary poem 'Voeluspa,' the 'Prophecy of the Sibyl,' which is entitled to stand not only at the head of the Eddic songs but of all old Germanic poetry, for the beauty and dignity of its style, its admirable choice of language, and the whole inherent worth of its material. Its purpose is to give a complete picture, although only in its most essential features, of the whole heathen religion. It contains in this way the entire history of the universe: the creation of the world out of chaos; the origin of the giants, the dwarfs, of gods, and of men; and ends with their destruction and ultimate renewal. The Sibyl is represented at the beginning in an assemblage of the whole human race, whom she bids be silent in order that she may be heard. Many of the strophes, even in translation, retain much of their inherent dignity and poetic picturesqueness:-- "There was in times of old where Ymir dwelt, nor land nor sea, nor gelid waves; earth existed not, nor heaven above; there was a chaotic chasm, and verdure nowhere. "Before Bur's sons raised up heaven's vault, they who the noble mid-earth shaped, the sun shone from the south on the structure's rocks; then was the earth begrown with green herbage.