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Many of our larger streams, such as the Mississippi, the Ohio, the Illinois, the Arkansas and the Red River, exhibit at certain seasons the most extensive overflowings of their waters, to which the name of floods is more appropriate than the term freshets, usually applied to the sudden risings of smaller streams. If we consider the vast extent of country through which an inland navigation is afforded by the never-failing supply of water furnished by these wonderful rivers, we cannot suppose them exceeded in magnitude by any other in the known world. It will easily be imagined what a wonderful spectacle must present itself to the eye of the traveller, who for the first time views the enormous mass of waters, collected from the vast central regions of our continent, booming along, turbid and swollen to overflowing, in the broad channels of the Mississippi and Ohio, the latter of which has a course of more than a thousand miles, and the former of several thousands.
To give you some idea of a Booming Flood of these gigantic streams, it is necessary to state the causes which give rise to it. These are, the sudden melting of the snows on the mountains, and heavy rains continued for several weeks. When it happens that, during a severe winter, the Alleghany Mountains have been covered with snow to the depth of several feet, and the accumulated mass has remained unmelted for a length of time, the materials of a flood are thus prepared. It now and then happens that the winter is hurried off by a sudden increase of temperature, when the accumulated snows melt away simultaneously over the whole country, and the south-easterly wind which then usually blows, brings along with it a continued fall of heavy rain, which, mingling with the dissolving snow, deluges the alluvial portions of the western country, filling up the rivulets, ravines, creeks and small rivers. These delivering their waters to the great streams, cause the latter not merely to rise to a surprising height, but to overflow their banks, wherever the land is low. On such occasions, the Ohio itself presents a splendid, and at the same time an appalling spectacle; but when its waters mingle with those of the Mississippi, then, kind reader, is the time to view an American flood in all its astonishing magnificence.
At the foot of the Falls of the Ohio, the water has been known to rise