Page:Popular Science Monthly Volume 73.djvu/21

Rh to the Gulf is about six hundred miles, the journey by water is twice as long. On every one of the many turns and bends throughout the whole twelve hundred miles the river is constantly undermining and wearing away the outer bank of the channel in just the same way as the outer rail of a curve on a railroad is worn rapidly and must soon be replaced. The fine-grained, loose character of the soil greatly facilitates the undermining action, especially during the irresistible rush of flood waters.

This habit of eating away its banks is perhaps the worst which can be charged against the lower Mississippi, and presents one of the most serious problems in the whole question of control. Needless to say the unceasing changing of the course is vitally important to the plantation owner, who sees his fertile land steadily vanishing, often at the rate of 300, 400 or more feet a year along his entire water front. It is still more important to the towns and shipping points located along the river. New Orleans is the only big city located directly on the river flat, and, fortunately for the city, it is at a place where the river's course is now comparatively straight. Other cities, like Memphis, Vicksburg and Natchez, are located on the high bluff where the river swings close against the eastern side of its valley. These latter towns have secured immunity from floods, but even simple changes in the channel would deprive them completely of their water fronts and strike fatal blows at their prosperity.

Even the present extent of the river traffic demands that there shall be more or less villages directly along the river and steamboat landings at various points, but every one of these places enjoys only a temporary existence. Since the river current hugs close along the outer side of every curve in its course, it follows that the deepest water, and hence the main channel, also lies near the outer bank. The natural result is that all steamboat landings and all important shipping points must be located on the outer banks of curves, as is found to be the case all along the river. The difficulty which lies therein is obvious enough, for with rapid undermining of the outer bank of all bends, the river is always tending to destroy the water front of every place so situated. The history of the landings below Cairo shows that practically every one of them has been driven back before the advancing river at the rate of 100 to 150 feet a year for the last quarter of a century.

That this condition is felt on a larger scale than by mere landings is shown by the case of Greenville, Mississippi. This city of nearly 8,000 people, the largest river port between Vicksburg and Memphis, is the flourishing commercial center for an important part of the lower valley, yet imminent ruin is even now staring it in the face. Greenville stands on the outer bank of a great curve in the river with three other curves up-stream from it. Narrow necks of land separate the