Shaking his great fist at the Asas, he shouted threateningly:
"Ye have tricked and fooled me enough. Not for nothing does a Frost Giant stand within the walls of Asgard. Were it not so strongly built I would now tear down this fortress that I have raised; but your own palaces are not giant-built, and see to it that they are not soon tumbling about your ears!"
And in good sooth he might have torn down the very halls of the Asas in his rage, had not Thor at that moment dashed up the Rainbow Bridge in his chariot drawn by goats. For all this while Thor, the strongest of the Asas, had been away on a long journey; and had this not been so, the giants would have had little cause to fear.
Springing from his chariot as the furious giant was about to pull the roof off Valhalla, Thor gave him so mighty a blow on the head with his huge hammer that his skull broke into little bits and his body fell down into the Land of Mists.
"Take that for your wages," roared Thor, as he swung his hammer on high, "and in this same manner will I repay all of the race of Frost Giants who seek to set foot in Asgard."
And so in this way was built for the Asas a fortress so strong that none of the giant folk could dare to raise hand against it. But always it lacked three stones in the gateway, for no one except a Frost Giant could lift such mighty blocks into place.