"They're as big as a canoe.

And they've got a sword as long as your leg, Uncle Andy, right in their tail, so they can stab whales and porpoises with it, just carelessly, without looking round, so as to make pretend it was an accident.

And they're quicker than greased lightning, Bill says.

So you see, if there was one here in the lake, we couldn't ever go in swimming." Uncle Andy refrained from smiling.

He puffed thoughtfully at his pipe for half a minute, while the Babe waited for his verdict.