Mr. Bixby served me in this fashion once, and for years afterward I used to blush even in my sleep when I thought of it.  I had become a good steersman; so good, indeed, that I had all the work to do on our watch, night and day; Mr. Bixby seldom made a suggestion to me; all he ever did was to take the wheel on particularly bad nights or in particularly bad crossings, land the boat when she needed to be landed, play gentleman of leisure nine-tenths of the watch, and collect the wages.  The lower river was about bank-full, and if anybody had questioned my ability to run any crossing between Cairo and New Orleans without help or instruction, I should have felt irreparably hurt.  The idea of being afraid of any crossing in the lot, in the day-time, was a thing too preposterous for contemplation.  Well, one matchless summer’s day I was bowling down the bend above island 66, brimful of self-conceit and carrying my nose as high as a giraffe’s, when Mr. Bixby said—­

‘I am going below a while.  I suppose you know the next crossing?’

This was almost an affront.  It was about the plainest and simplest crossing in the whole river.  One couldn’t come to any harm, whether he ran it right or not; and as for depth, there never had been any bottom there.  I knew all this, perfectly well.

‘Know how to run it?  Why, I can run it with my eyes shut.’

‘How much water is there in it?’

’Well, that is an odd question.  I couldn’t get bottom there with a church steeple.’

‘You think so, do you?’

The very tone of the question shook my confidence.  That was what Mr. Bixby was expecting.  He left, without saying anything more.  I began to imagine all sorts of things.  Mr. Bixby, unknown to me, of course, sent somebody down to the forecastle with some mysterious instructions to the leadsmen, another messenger was sent to whisper among the officers, and then Mr. Bixby went into hiding behind a smoke-stack where he could observe results.  Presently the captain stepped out on the hurricane deck; next the chief mate appeared; then a clerk.  Every moment or two a straggler was added to my audience; and before I got to the head of the island I had fifteen or twenty people assembled down there under my nose.  I began to wonder what the trouble was.  As I started across, the captain glanced aloft at me and said, with a sham uneasiness in his voice—­

‘Where is Mr. Bixby?’

‘Gone below, sir.’

But that did the business for me.  My imagination began to construct dangers out of nothing, and they multiplied faster than I could keep the run of them.  All at once I imagined I saw shoal water ahead!  The wave of coward agony that surged through me then came near dislocating every joint in me.  All my confidence in that crossing vanished.  I seized the bell-rope; dropped it, ashamed; seized it again; dropped it once more; clutched it tremblingly one again, and pulled it so feebly that I could hardly hear the stroke myself.  Captain and mate sang out instantly, and both together—­