Once upon a time there lived a king who was deeply in love with a princess, but she could not marry anyone, because she was under an enchantment. So the King set out to seek a fairy, and asked what he could do to win the Princess's love. The Fairy said to him:
"You know that the Princess has a great cat which she is very fond of. Whoever is clever enough to tread on that cat's tail is the man she is destined to marry."
The King said to himself that this would not be very difficult, and he left the Fairy, determined to grind the cat's tail to powder rather than not tread on it at all.
You may imagine that it was not long before he went to see the Princess, and puss, as usual, marched in before him, arching his back. The King took a long step, and quite thought he had the tail under his foot, but the cat turned round so sharply that he only trod on air. And so it went on for eight days, till the King began to think that this fatal tail must be full of quicksilver—it was never still for a moment.