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a very swift current; but when the river is low, the rocks appear, and divide the stream into a number of separate channels, the main passage being on the west side. Twenty-five miles below the falls, Salt River, a considerable stream, sets in from the eastward; soon after which, the river makes a bend to the N. W. for about 48 miles, and turning again in a south-west direction, but with considerable bends, it passes on toward Evansville, distant 109 miles, near which Green River falls in from the eastward. Green River is a considerable stream, rising in a south-east direction upwards of 200 miles distant. Below Green River the Ohio makes considerable bends, though the general direction is S. W. to the Wabash, distant 53 miles. The Wabash is a large river, rising N. E. above 400 miles, and receives in its progress many tributary streams. From the Wabash, the river runs in a direction a little west of south to Smithland, where the Cumberland River falls in from the eastward. The Cumberland is a large river rising on the W. side of the Cumberland Mountains, and pursuing a meandering course, generally in a western direction, to the Ohio. It is navigable for about 400 miles. Twelve miles below the Cumberland River, the Tennessee River falls in from the eastward. This is one of the largest of the tributary streams of the Ohio. Its head waters spread into Virginia, North Carolina, and Georgia, and unite at Kingston, below Knoxville. The river conti

nues thence a course of about 450 miles through Tennessee and Alabama, during which it receives a great number of tributary streams, and falls into the Ohio at this place. It is navigable a great way into the interior of the country, without any other obstruction than the Muscle Shoals, distant from the outlet about 260 miles. At Tennessee River, the Ohio makes a pretty large bend to the N. W.

and then turns south-west, and at the distance of 46 miles from Tennessee River falls into the Mississippi.

It has been stated that the Ohio at Pittsburg was nearly 600 yards broad. It continues at nearly that breadth duing a great part of its progress, extending in volume as it approaches the Mississippi, where it is above half a mile wide. It runs a great part of the way in a deep valley, capable of containing within its high banks the great volume of water, which it rolls down during its periodical swells, which is sometimes more than 50 feet deep. Including its branches it is estimated that it spreads over a country about 205,000 square miles in extent, having ground of remarkable fertility, so that it must in process of time become the seat of a vast population.

The Mississippi, after its junction with the Ohio, is unquestionably one of the largest rivers in the world; but from the particular nature of the ground through which it flows, it does not spread wide; but it runs deep, and the current is very powerful, the waters being turbulent and muddy. At its junction with the Ohio it is about threequarters of a mile wide, which may be assumed as its average width, until its outlet in the Ocean. Its course from here is generally south, although it makes, besides its minute windings, a general bend to the westward; and then again to the east. Passing over a number of minor streams which fall into it on both sides, the first we shall notice is the St. Francis, a large stream which falls in from the north-west, 267 miles from the Ohio. Below this 60 miles, the White River, a stream upwards of 500 miles long, falls in from the west, and 12 miles below it is the outlet of the great Arkansas River. This river rises in the Rocky Mountains, near the head waters of the Missouri, and pursuing a south-east course, while the Missouri flows north-east: the waters finally mingle here, after the Ar

kansas has flowed upwards of 1300 miles. Below the Arkansas 166 miles, the Yazoo River falls in from the eastward, and 57 miles below that, the Big Black River from the same side. Fifty-eight miles below Black River, the Mississippi passes Natches, one of the oldest settlements on its banks; and below it 47 miles, is Fort Adams, where the river makes a considerable bend, and 14 miles below Fort Adams, it receives the united waters of the Red River and Washita, from the westward. The Red River is a very large stream, rising near Santa Fe, about 900 miles N. W. from its outlet, and is, for a considerable distance, the southern boundary of the United States. Ten miles before its junction with the Mississippi, it receives the Washita, from the northward, which is a large stream, rising about 400 miles north-west. The Great Mississippi River has now reached its maximum. It receives no more streams of importance, but it gives out several very important branches, in its progress toward the Ocean. The main river, however, does not diminish in size, nor velocity, and we may view it in its progress to the Ocean, as being on an average about 1000 yards wide, 120 feet deep, and its mean velocity about 3 miles an hour. Three miles below the Red River, a large and rapid branch called the Atchafalaya, passes off to the southward, and running in that direction about 150 miles, falls into the Gulf of Mexico, through Atchafalaya Bay. Below this, about 90 miles, the Manchac or Iberville River, passes out of the Mississippi to the eastward, and flows into Lake Borgne, a branch of the Ocean, through Lake Pontchartrain. Below 34 miles, the River La Fourche, passes off to the south at Donaldsonville; after which there is nothing very material, until the river reaches the great depot of NewOrleans, situated on the north bank, 89 miles below La Fourche. Below New-Orleans, about 19 miles, is the

English Turn, a remarkable bend in the river, and 55 miles below it, is Fort St. Philip, at Placquemine, which completely commands the river. Twenty miles below the Fort, the river forks off into three grand divisions, called the South-East or Main Pass; the South Pass; and the South-West Pass. Four miles below the forks, on the Main Pass, a stream issues to the north-east, called Pass à la Loutre, and the Main Pass is also divided into two parts at the outlet; the western one being called the West Pass. On all these passes there are bars at the outlets, with the water comparatively shallow. The Main Pass has about 13 feet, the South-West Pass 12; the West Pass 9, and the South Pass 8. The course of the river can be traced a considerable way from the outlets, when it is finally lost in the mass of waters forming the Gulf of Mexico.

The Mississippi and its waters, after its junction with the Ohio, spread over a territory of above 290,000 square miles.

As to the quantity of water sent down by this mighty stream, the following calculations have been made, as matter of curiosity, and for the purpose of forming a contrast between this river and the St. Lawrence. It may be observed, however, that all calculations of this kind must necessarily be very vague. The best position for forming the estimate in view, appears to be between the Red River and the Atchafalaya. It has been already stated that the river was there about 1000 yards wide, 120 feet deep, and its velocity 3 miles an hour. But from the nature of the ground through which it passes, the deepest part will be in the middle, and the bottom will slope from each side; the current will also be diminished in velocity, as the waters approach the bed of the river. We may, therefore, reduce the width to half a mile, and deduct one-third each from the depth and the velocity:

and this will leave the following data:-the river half a mile wide, 80 feet deep, and velocity two miles per hour. The result will be, that it discharges 2,230,272,000 cubic feet of water every hour, being 37,171,200 cubic feet, or 227,775,000 gallons each minute. It is presumed that this calculation is rather underrated, and the result is, that the water discharged by this river is more than double that discharged by the St. Lawrence.

As to the descent of the Missouri, from its source to its outlet, we have no data for forming a very correct estimate. It has been found that the base of the Rocky Mountains, near the sources of the Platte, is about 3500 feet above the level of the sea; and to this we may safely add 500 feet more, making a total of 4000 feet for the elevation of the head waters of the Missouri. The highest point of the waters of the Ohio, is probably at as great an elevation as the highest point of the Mississippi, namely, 1330 feet. Pittsburg is estimated at about 800 feet above the tide water, and it is probable that the highest point of Alleghany River, in Potter County, is at least 530 feet above Pittsburg.

The area of the districts watered by the different main branches have been stated in round numbers, and it may now be satisfactory to present a view of the various states and territories watered by these great streams, and to form an estimate of the quantity of territory watered in each. The result will present a view that few would have anticipated.

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