Read it through once

'Now watch her; watch her like a cat, or she'll get away from you. When she fights strong and the tiller slips a little, in a jerky, greasy sort of way, let up on her a trifle; it is the way she tells you at night that the water is too shoal; but keep edging her up, little by little, toward the point. You are well up on the bar, now; there is a bar under every point, because the water that comes down around it forms an eddy and allows the sediment to sink. Do you see those fine lines on the face of the water that branch out like the ribs of a fan. Well, those are little reefs; you want to just miss the ends of them, but run them pretty close. Now look out--look out! Don't you crowd that slick, greasy-looking place; there ain't nine feet there; she won't stand it. She begins to smell it; look sharp, I tell you! Oh blazes, there you go! Stop the starboard wheel! Quick! Ship up to back! Set her back!