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Then spoke Gangleri: “It was quite an achievement of Loki’s when he brought it about first of all that Baldr was killed, and also that he was not redeemed from Hel. But was he punished at all for this?”

High said: “He was requited for this in such a way that he will not soon forget it. The gods having become as angry with him as one might expect, he ran away and hid in a certain mountain, built a house there with four doors so that he could see out of the house in all directions. But in the daytime he often turned himself into the form of a salmon and hid in a place called Franangr waterfall. Then he pondered what sort of device the Æsir would be likely to think up to catch him in the waterfall. And as he sat in the house he took some linen thread and tied knots in it in the way in which ever since a net has been. A fire was burning in front of him. Then he noticed that the Æsir were only a short distance away from him, and Odin had seen where he was from Hlidskialf. He immediately jumped up and out into the river throwing the net down into the fire. And when the Æsir reached the house then the first to enter was the wisest of all, called Kvasir. And when he saw in the fire the shape in the ashes where the net had burned he realized that it must be a device to catch fish, and told the Æsir. After that they went and made themselves a net just like what they saw in the ashes that Loki had made. And when the net was finished the Æsir went to the river and threw the net into the waterfall. Thor held one end and all the Æsir held the other and they dragged the net. But Loki went along in front and lay down between two stones. They dragged the net over him and could tell there was something live there and went a second time up to the waterfall and threw out the net and weighted it down so heavily that nothing would be able to go underneath. Then Loki went along in front of the net, and when he saw that it was only a short way to the sea then he leaped up over the top of the net and slipped up into the waterfall. This time the Æsir saw where he went, they went back up to the waterfall and divided their party into two groups, and Thor waded along the middle of the river and thus they advanced towards the sea. And when Loki saw there were two alternatives—it was mortal danger to rush into the sea, but so it was also to leap again over the net—and this is what he did, leaped as swiftly as he could over the top of the net. Thor grabbed at him and got his hand round him and he slipped in his hand so that the hand caught hold at the tail. And it is for this reason that the salmon tapers towards the tail.

“Now Loki was captured without quarter and taken to a certain cave. Then they took three stone slabs and set them on edge and knocked a hole in each slab. Then Loki’s sons Vali and Nari or Narfi were fetched. The Æsir turned Vali into the form of a wolf and he tore his brother Narfi to pieces. Then the Æsir took his guts and bound Loki with them across the three stones—one under his shoulders, one under his loins, the third under the backs of his knees—and these bonds turned to iron. Then Skadi got a poisonous snake and fixed it up over him so that the poison would drip from the snake into his face. But his wife Sigyn stands next to him holding a basin under the drops of poison. And when the basin is full she goes and pours away the poison, but in the meantime the poison drips into his face. Then he jerks away so hard that the whole earth shakes. That is what you call an earthquake. There he will lie in bonds until Ragnarok.”

– from the “Gylfaginning” in the Prose Edda,
translated by Anthony Faulkes, Edda, 51-52