“Well, pile it on me; I might as well have it now as another time.”

“You see, this has got to be learned; there isn’t any getting around it.  A clear starlight night throws such heavy shadows that, if you didn’t know the shape of a shore perfectly, you would claw away from every bunch of timber, because you would take the black shadow of it for a solid cape; and, you see, you would be getting scared to death every fifteen minutes by the watch.  You would be fifty yards from shore all the time when you ought to be within fifty feet of it.  You can’t see a snag in one of those shadows, but you know exactly where it is, and the shape of the river tells you when you are coming to it.  Then there’s your pitch-dark night; the river is a very different shape on a pitch-dark night from what it is on a starlight night.  All shores seem to be straight lines, then, and mighty dim ones, too; and you’d run them for straight lines, only you know better.  You boldly drive your boat right into what seems to be a solid, straight wall (you know very well that in reality there is a curve there), and that wall falls back and makes way for you.  Then there’s your gray mist.  You take a night when there’s one of these grisly, drizzly, gray mists, and then there isn’t any particular shape to a shore.  A gray mist would tangle the head of the oldest man that ever lived.  Well, then, different kinds of moonlight change the shape of the river in different ways.  You see——­”

“Oh, don’t say any more, please!  Have I got to learn the shape of the river according to all these five hundred thousand different ways?  If I tried to carry all that cargo in my head it would make me stoop-shouldered.”

“No! you only learn the shape of the river; and you learn it with such absolute certainty that you can always steer by the shape that’s in your head, and never mind the one that’s before your eyes.”

    “Very well, I’ll try it; but, after I have learned it, can I depend
    on it?  Will it keep the same form, and not go fooling around?”

    Before Mr. Bixby could answer, Mr. W. came in to take the watch, and
    he said: 

“Bixby, you’ll have to look out for President’s island, and all that country clear away up above the Old Hen and Chickens.  The banks are caving and the shape of the shores changing like everything.  Why, you wouldn’t know the point about 40.  You can go up inside the old sycamore snag now.”

So that question was answered.  Here were leagues of shore changing shape.  My spirits were down in the mud again.  Two things seemed pretty apparent to me.  One was that in order to be a pilot a man had got to learn more than any one man ought to be allowed to know; and the other was that he must learn it all over again in a different way every twenty-four hours.

I went to work now to learn the shape