WHOSOEVER has done me the courtesy to read my chapters which have preceded this may possibly wonder that I deal so minutely with piloting as a science.

It was the prime purpose of those chapters; and I am not quite done yet.

I wish to show, in the most patient and painstaking way, what a wonderful science it is.

Ship channels are buoyed and lighted, and therefore it is a comparatively easy undertaking to learn to run them; clear-water rivers, with gravel bottoms, change their channels very gradually, and therefore one needs to learn them but once; but piloting becomes another matter when you apply it to vast streams like the Mississippi and the Missouri, whose alluvial banks cave and change constantly, whose snags are always hunting up new quarters, whose sandbars are never at rest, whose channels are for ever dodging and shirking, and whose obstructions must be confronted in all nights and all weathers without the aid of a single light-house or a single buoy; for there is neither light nor buoy to be found anywhere in all this three or four thousand miles of villainous river.{footnote [True at the time referred to; not true now (1882).]} I feel justified in enlarging upon this great science for the reason that I feel sure no one has ever yet written a paragraph about it who had piloted a steamboat himself, and so had a practical knowledge of the subject.

If the theme were hackneyed, I should be obliged to deal gently with the reader; but since it is wholly new, I have felt at liberty to take up a considerable degree of room with it.
When I had learned the name and position of every visible feature of the river; when I had so mastered its shape that I could shut my eyes and trace it from St.Louis to New Orleans; when I had learned to read the face of the water as one would cull the news from the morning paper; and finally, when I had trained my dull memory to treasure up an endless array of soundings and crossing-marks, and keep fast hold of them, I judged that my education was complete: so I got to tilting my cap to the side of my head, and wearing a tooth-pick in my mouth at the wheel.