Red Loki had been up to mischief again! Loki, who made quarrels and brought trouble wherever he went. He had a wicked heart, and he loved no one. He envied Father Odin his wisdom and his throne above the world. He envied Balder his beauty, and Tŷr his courage, and Thor his strength. He envied all the good Æsir who were happy; but he would not take the trouble to be good himself. So he was always unhappy, spiteful, and sour. And if anything went wrong in Asgard, the kingdom of the gods, one was almost sure to find Loki at the bottom of the trouble. Now Thor, the strongest of all the gods, was very proud of his wife's beautiful hair, which fell in golden waves to her feet, and covered her like a veil. He loved it better than anything, except Sif herself. One day, while Thor was away from home, Loki stole into Thrudheim, the realm of clouds, and cut off all Sif's golden hair, till her head was as round and fuzzy as a yellow dandelion. Fancy how angry Thor was when he came rattling home that night in his thunder-chariot and found Sif so ugly to look at! He stamped up and down till the five hundred and forty floors of his cloud palace shook like an earthquake, and lightning flashed from his blue eyes. The people down in the world below cried: "Dear, dear! What a terrible thunderstorm! Thor must be very angry about something. Loki has been up to mischief, it is likely." You see, they also knew Loki and his tricks. At last Thor calmed himself a little. "Sif, my love," he said, "you shall be beautiful again. Red Loki shall make you so, since his was the unmaking. The villain! He shall pay for this!" Then, without more ado, off set Thor to find red Loki. He went in his thunder-chariot, drawn by two goats, and the clouds rumbled and the lightning flashed wherever he went; for Thor was the mighty god of thunder. At last he came upon the sly rascal, who was trying to hide. Big Thor seized him by the throat. "You scoundrel!" he cried, "I will break every bone in your body if you do not put back Sif's beautiful hair upon her head." "Ow--ow! You hurt me!" howled Loki. "Take off your big hand, Thor. What is done, is done. I cannot put back Sif's hair. You know that very well." "Then you must get her another head of hair," growled Thor. "That you can do. You must find for her hair of real gold, and it must grow upon her head as if it were her own. Do this, or you shall die." "Where shall I get this famous hair?" whined Loki, though he knew well enough. "Get it of the black elves," said Thor; "they are cunning jewelers, and they are your friends. Go, Loki, and go quickly, for I long to see Sif as beautiful as ever."