FALLS OF THE MISSOURI.
The most prominent features of this great river, which is fed by so many streams, having their sources in a great variety of soils and climates, are its wonderful falls, rapids and cascades, the following connected view of which is abstracted from the very accurate draught and survey made by Captain Clarke.
This river is nine hundred feet wide at the point where it receives the waters of Medicine river, which is four hundred and one feet in width. The united current continues five thousand, four hundred and twelve feet, somewhat more than a mile, to a small rapid on the north side, from which it gradually widens to four thousand, two hundred feet, and at the distance of nine thousand and forty-two feet, (nearly a mile and three-fourths,) reaches the head of the rapids, narrowing as it approaches them. Here the hills on the north, which had withdrawn from the bank, closely border the river, which, for the space of a mile, makes its way over the rocks with a descent of thirty feet: in this course the current is contracted to sixteen hundred and forty feet, and, after throwing itself over a small pitch of five feet, forms a beautiful cascade of twenty-six feet, five inches; this does not, however, fall quite perpendicularly, being stopped by a part of the rock, which projects at about one-third of the distance. After descending this fall, and passing the Cotton-wood island, on which the eagle has fixed its nest, the river goes on for eight thousand, seven hundred and seventy-eight feet, (more than a mile and a half,) over rapids and little falls, the estimated descent of which is thirteen feet six inches, till it is joined by a large fountain boiling up underneath the rocks near the edge of the river, and falling into it with a cascade of eight feet. It is of the most perfect clearness, and rather of a bluish cast; and even after falling into the Missouri it preserves its color for half a mile. From this fountain the river descends with increased rapidity for the distance of thirty-five hundred and thirty-one feet, during which the estimated descent is five feet: from this, for a distance of twenty-two hundred and twenty-seven feet, the river descends fourteen feet seven inches, including a perpendicular fall of six feet seven inches. The river has now become pressed into a space of fourteen hundred and nineteen feet, and here forms a grand cataract, by falling over a plain rock, the whole distance across the river, to the depth of forty-seven feet, eight inches: after recovering itself, the Missouri then proceeds with an estimated descent of three feet, till at the distance of sixteen hundred and eighty-three feet it again is precipitated down the crooked falls, nineteen feet perpendicularly; below this at the mouth of a deep ravine, is a fall of five feet, after which, for the distance of sixteen thousand and five feet, (upward of three miles,) the descent is much more gradual, not being more than ten feet, and then succeeds a handsome level plain for the space of twenty-nine hundred and thirty-seven feet, (more than half a mile,) with a computed descent of three feet, making a bend toward the north. Thence it descends, during seventy-nine hundred and twenty feet, about eighteen feet and a half, when it makes a perpendicular fall of two feet, which is fourteen hundred and eighty-five feet beyond the great cataract, in approaching which it descends thirteen feet, within a distance of about six hundred feet, and gathering strength from its confined channel, which is only eight hundred and forty feet wide, rushes over the fall to the depth of eighty-seven feet and three-quarters of an inch. After raging among the rocks, and losing itself in foam, it is compressed immediately into a bed of two hundred and seventy-nine feet in width; it continues for fifty-six hundred and ten feet to the entrance of a run or deep ravine, where there is a fall of three feet, which, joined to the decline of the river during that course, makes the descent six feet. As it goes on, the descent within the next thirty-nine hundred and sixty feet is only four feet; from this, passing a run or deep ravine, the descent for sixteen hundred feet is thirteen feet: within thirty-nine hundred and sixty feet, is a second descent of eighteen feet; thence twenty-six hundred and forty feet further, is a descent of six feet; after which, to the mouth of Portage creek, a distance of forty-six hundred and twenty feet, the descent is ten feet. From this survey and estimate it results that the river experiences a descent of three hundred and fifty-two feet in the course of fifteen or sixteen miles, from the commencement of the rapids, to the mouth of Portage creek, exclusive of almost impassable rapids which extend for a mile below its entrance.