Read it through once

An embankment ten or fifteen feet high guards both banks of the Mississippi all the way down that lower end of the river, and this embankment is set back from the edge of the shore from ten to perhaps a hundred feet, according to circumstances; say thirty or forty feet, as a general thing. Fill that whole region with an impenetrable gloom of smoke from a hundred miles of burning bagasse piles, when the river is over the banks, and turn a steamboat loose along there at midnight and see how she will feel. And see how you will feel, too! You find yourself away out in the midst of a vague dim sea that is shoreless, that fades out and loses itself in the murky distances; for you cannot discern the thin rib of embankment, and you are always imagining you see a straggling tree when you don't. The plantations themselves are transformed by the smoke, and look like a part of the sea. All through your watch you are tortured with the exquisite misery of uncertainty. You hope you are keeping in the river, but you do not know. All that you are sure about is that you are likely to be within six feet of the bank and destruction, when you think you are a good half-mile from shore. And you are sure, also, that if you chance suddenly to fetch up against the embankment and topple your chimneys overboard, you will have the small comfort of knowing that it is about what you were expecting to do. One of the great Vicksburg packets darted out into a sugar plantation one night, at such a time, and had to stay there a week. But there was no novelty about it; it had often been done before.