The Mississippi is notable for its varying length.  Within the memory of the oldest pilot the length of the river between St. Louis and New Orleans has varied more than one hundred and fifty miles, being sometimes longer and sometimes shorter, as the year may be one of drought or of excessive rainfall.  Occasionally the river will shorten itself a score of miles at a single leap.  The shortening invariably takes place at one of its long sinuous curves for which it is so remarkable.  At a season when the volume of water begins to increase, the narrow neck of the loop gives way little by little under the continuous impact of the strengthening current.  Narrower and narrower it grows as the water ceaselessly cuts away the bank.  Finally the barrier is broken; there is a tumultuous meeting of waters; the next steamboat that comes along goes through a new cut; and a moat or ox-bow lake is the only reminder of the former channel.[5]

[Footnote 5:  One of the most noteworthy examples of these cut-offs is Davis’.  This cut-off occurred at Palmyra Bend, eighteen miles below Vicksburg.  The mid-channel distance around the bend was not far from twenty miles; the neck was only twelve hundred feet across.  The fall of the river, measured around the bend, was about four inches per mile; the slope, measured across the neck, was about five and one-half feet, nearly twenty feet per mile.  Inasmuch as the soil in the neck was wholly alluvial, the current cut its new channel with exceedingly great rapidity, soon clearing it out a mile in width and more than one hundred feet in depth.  The water rushed through the channel with such a velocity that steamboats could not breast its flow for many weeks, while the roaring of its flood could be heard many miles away.  The influence of the cut-off was felt both above and below Vicksburg for several years after.  The rate of erosion has been perceptibly increased above Vicksburg:  and it is not unlikely that the cut-off which occurred a few years later at Commerce, about thirty miles below Memphis, was a result of Davis’ Cut.  Other recent cut-offs have occurred near Arkansas City, below Greenville, near Duncansby, below Lake Providence at Vicksburg, and at Kienstra.  The latter place is below Natchez; all the others are between Natchez and Memphis.  A double cut-off is strongly threatened at Greenville.]

In 1863 the city of Vicksburg was situated on the outer curve of such a loop.  At that time General Grant and his army were on the opposite side of the river, and the whole power of the Federal government was directed upon devising how the army might cross it and capture the long-beleagured city.  So an army engineer conceived the idea of turning the river around the rear of the army.  Accordingly, a canal was cut across the loop, in order to make an artificial channel through which its current might run.  But the river steadfastly refused to accept any channel it had not itself made, and the ditch soon silted