In this place you may swim. By this sign and this you will know if it is safe to do so, said Fiacuil mac Cona; but in this place, with this sign on it and that, you must not venture a toe.
But where Fionn would venture his toes his ears would follow.
There are coiling weeds down there, the robber counselled him; there are thin, tough, snaky binders that will trip you and grip you, that will pull you and will not let you go again until you are drowned; until you are swaying and swinging away below, with outstretched arms, with outstretched legs, with a face all stares and smiles and jockeyings, gripped in those leathery arms, until there is no more to be gripped of you even by them.
“Watch these and this and that,” Fionn would have been told, “and always swim with a knife in your teeth.”
He lived there until his guardians found out where he was and came after him. Fiacuil gave him up to them, and he was brought home again to the woods of Slieve Bloom, but he had gathered great knowledge and new supplenesses.
The sons of Morna left him alone for a long time. Having made their essay they grew careless.
“Let him be,” they said. “He will come to us when the time comes.”
But it is likely too that they had had their own means of getting information about him. How he shaped? what muscles he had? and did he spring clean from the mark or had he to get off with a push? Fionn stayed with his guardians and hunted for them. He could run a deer down and haul it home by the reluctant skull. “Come on, Goll,” he would say to his stag, or, lifting it over a tussock with a tough grip on the snout, “Are you coming, bald Cona’n, or shall I kick you in the neck?”
The time must have been nigh when he would think of taking the world itself by the nose, to haul it over tussocks and drag it into his pen; for he was of the breed in whom mastery is born, and who are good masters.
But reports of his prowess were getting abroad. Clann-Morna began to stretch itself uneasily, and, one day, his guardians sent him on his travels.