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prairies and grove lands, which cannot square less than two by four hundred miles, constitute the ancient area of the Issati,* and are now the resort of great herds of the buffalo, elk, and deer; and it is a region known as the predatory border, or battle-ground of the Chippewas and Dacotas.

* Vide Hennepin.

CHAPTER XI.

Physical traits of the Mississippi-The elevation of its sources-Its velocity and mean descent-Etymology of the name Mississippi-Descent of the river to Sandy Lake, and thence to the Falls of St. Anthony-Recross the great Bitobi Savanna-Pakagama formation-Description of the voyage from Sandy Lake to Pine River-Brief notices of the natural history.

THE third geographical division in which it is proposed to consider the Mississippi, begins at the Falls of St. Anthony. Within half a day's march, before reaching this point from its sources, the primitive and crystallized, and the altered and basaltic rocks are succeeded by the great limestone and sandstone horizontal series of the carboniferous, magnesian, and metalliferous rocks, which constitute by themselves so extraordinary a body of geological phenomena. Entering on the level of the white sandstone stratum, which is fundamental in this column, about the inlet of Rum River, the Mississippi urges its way over a gently inclining bed of this rock, to the brink of this cataract, where it drops perpendicularly about sixteen feet; but the whole descent of its level from the head to the foot of the portage path, cannot be less than double that height.

The river, at this point, enters a valley which is defined by rocky cliffs, which attain various elevations from one to three hundred feet, presenting a succession of picturesque or sublime views. In some places these cliffs present a precipitous and abrupt façade, washed by the current. In far the greatest number of cases, the eminence has lost its sharp angles through the effects of frosts, rains, and elemental action, leaving a slope of debris at the foot. As the river descends, it increases in volume and in the extent of its alluvions. These form, in an especial manner, its characteristic features from St. Anthony's Falls to the junction of the Missouri, a distance of not less than eight hundred miles. The principal

tributaries which it receives in this distance, are, on the right, the St. Peter's, Upper and Lower Iowa, Turkey River, Desmoines, and Salt Rivers; and, on the left, the St. Croix, Chippewa, Wisconsin, Rock River, and the Illinois. One hundred miles below St. Anthony, it expands for a distance of twenty-four miles into the sylvan sheet of Lake Pepin, at the foot of which it receives the large volume of the Chippewa River, which originates on the sandy tracts at the sources of the Wisconsin, Montreal, and Ontonagon; and it is from this point that its continually widening channel exhibits those innumerable and changing sand-bars, which so embarrass the navigation. But in all this distance, it is only at the Desmoines and Rock River rapids that any permanent serious impediment is found in its navigation, with the larger craft.

The fourth change in the physical aspect of this river, is at the junction of the Missouri, and this is an almost total and complete one; for this river brings down such a vast and turbid flood of commingled earths and floating matter, that it characterizes this stream to its entrance into the Gulf of Mexico. If its length of channel, velocity, and other leading phenomena had been accurately known at an early day, it should also have carried its name from this point to the ocean. Down to this point, the Mississippi, at its summer phases, carries the character of a comparatively clear stream. But the Missouri, which, from its great length and remote latitude, has a summer freshet, flows in with a flood so turbid and opaque, that it immediately communicates its qualities and hue to the milder Mississippi. At certain seasons, the struggle between the clear and turbid waters of the two streams can be seen, at opposite sides of the river, at the distance of twenty or thirty miles. Entire trees, sometimes ninety feet long, with their giant arms, are swept down the current; and it is not unusual, at its highest flood, to observe large, spongy masses of a species of pseudo pumice carried into its channel, from some of its higher western tributaries.

To such a moving, overpowering liquid mass, there are still, below the Missouri, rocky banks, and occasionally isolated cliffs, to stand up and resist its sweep; but its alluvions become wider and deeper opposite to these rocky barriers. Its bends stretch. over greater distances, and its channel grows deeper at every accession of a tributary. The chief of these, after passing the

Missouri, are from the Rocky Mountains and Ozark slopes, the St. Francis, White, Arkansas, and Red Rivers; and from the other bank the Kaskaskia, the Ohio, Wolf, and Yazoo. It is estimated to flow twelve hundred miles below the Missouri. Its width is about one mile opposite St. Louis. It is narrower but more than twice the depth at New Orleans, and yet narrower, because more divided, at its embouchure at the Balize, where a bar prevents ships drawing over eighteen feet of water from entering.

No attempt has heretofore been made to determine the elevation of that part of the American continent which gives rise to the Mississippi River. From the observations made on the expedition, the elevation is confessedly less than would à priori be supposed. If it is not, like the Nile, cradled among mountains, whose very altitude and position are unknown, there is enough of the unknown about its origin to wish for more information. Originating on a vast continental plateau, or water-shed, the superabundance of its waters are drained off by the three greatest rivers of North America, namely, the St. Lawrence, the Nelson's rivers of Hudson's Bay, and the Mississippi. Yet the apex of this height of land is moderate, although its distance from the sea at either point is immense. From the best data at command, I have endeavored to come at the probable altitude of this plateau, availing myself at the same time of the judgment of the several members of the expedition. Taking the elevation of Lake Erie above tide-water, as instrumentally determined, in the New York surveys, as a basis, we find Lake Superior lying at an altitude of six hundred and forty-one feet above the Atlantic. From thence, through the valley of the St. Louis, and across the Savanna summit, to the Mississippi, at the confluence of the Sandy Lake River, estimates noted on the route, indicate an aggregate rise of four hundred and ninety feet. The ascent of the river, from this point to Cass Lake, is estimated to be one hundred and sixty-two feet; giving this lake an aggregate elevation of thirteen hundred and ninety-three feet above the Atlantic. Barometrical admeasurements made in 1836, by Mr. Nicollet, in the service of the United States Topographical Bureau, place the elevation of this lake at fourteen hundred and two feet above the Gulf of Mexico,* being just twelve feet above these early estimates. The

* Senate Document No. 237, 26 Con. 2d Session, A. D. 1843.

same authority estimates its length from the Balize, at twentyseven hundred and fifty miles. Its velocity below Cass Lake may be estimated to result from a mean descent of a fraction over five inches per mile.

The name of the Mississippi River is derived from the Algonquin language, through the medium of the French. The term appears first in the early missionary letters from the west end of Lake Superior about 1660. Sippi, agreeably to the early French annotation of the word, signifies a river. The prefixed word Missi is an adjective denoting all, and, when applied to various waters, means the collected or assembled mass of them. The compound term is then, properly speaking, an adverb. Thus, Missi-gago, means all things; Missi-gago-gidjetod, He who has made all things-the Creator. It is a superlative expression, of which great river simply would be a most lean, impracticable, and inadequate expression. It is only symbolically that it can be called the father of American rivers, unless such sense occurs in the other Indian tongues.

Finding it impracticable to proceed higher in the search of the remote sources of the river at this time, a return from this point was determined on. The vicinity had been carefully scanned for its drift specimens, and fresh-water conchology. Wishing to carry along some further memorial of the visit, members of the party cut walking-canes in the adjoining thickets, and tied them carefully together; and at five o'clock in the afternoon (21st July) we embarked on our descent. An hour's voyage over the surface of this wide lake, with its refreshing views of northern scenery, brought us to the point where the Mississippi issues from it. Never did men ply their paddles with greater animation; and having the descent now in their favor, they proceeded eighteen miles before they sought for a spot to encamp. Twilight still served, with almost the clearness of daylight, while we spread our tents on a handsome eminence on the right-hand shore. Daylight had not yet dawned the next morning, when we resumed the descent. It was eight o'clock A.M. when we reached the border of Lake Winnipek. This name, by the way, is derived from a term heretofore given, which, having the Chippewa inflection of nouns in ish, graphically describes that peculiarity of its waters created by the disturbance of a clay bottom.

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