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overflow, but these differ in many respects from the Lower Delta, and need not be described here.

The Mississippi river forms the eastern boundary of this state from the 38d degree of latitude to the mouth of Red river at the 31st degree, a distance of S06 miles by water; and its course thence to the Gulf of Mexi co is 326; in all 632 miles. In its course through the low country this river overflows its natural banks, and the waters which pass over on the west side never return. Those which escape on the east side rejoin the parent stream, except between Baton Rouge and Manchac, where, by the channel of the Ibberville and Amite rivers, they find a passage to lakes Maurepas and Ponchartrain, which communicate with the ocean. mean width is 880 yards, though in many places near islands and shoals it is much greater; and it is wider 1000 miles from the sea than near its mouth. At Natchez, opposite Fort Rosalie, it is 620 yards. Nine miles below the efflux of the Fourche river, the depth from the highest bank was found to be 153 feet. The difference between high and low water here is twentythree feet, which gives a constant depth of 130 feet; but the passes, or channels, through which it discharges its waters into the gulf, have no more

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The low water level of the Mississippi at this place is found to be ten feet above the common level of Lake Ponchartrain, which has eighteen feet water. The bottom of the river here is therefore 102 feet below that of the lake; of course the idea which some have that an opening here would carry off the entire body of the river water is unfounded.-Darby, p. 135.

than twelve feet at low water. A regular ebb and flow from twelve to eighteen inches takes place as high as New Orleans, 108 miles from the mouth of the river. The waters of this river, in consequence of the dissolution of the snows of the northern regions, and the fall of rains, begin to rise in January, and subside in June, though sometimes at an earlier period. In 1812 they rose to their greatest height in the month of December, which the oldest inhabitant had never before witnessed. Between the mouth of the Ohio and Natchez the waters rise fifty feet; at Baton Rouge, twenty-five; and at New Orleans, twelve. The average rise above New Orleans has been estimated at thirty feet,

Table of the mean rise of the Waters of the Mississip pi at Natchez, from the lowest ebb to the highest elevation.*

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By William Dunbar. See 6th volume of the Transactions of

the Philosophical Society of Philadelphia.

Levee. To protect the arable soil from this annual flood, a bank of earth, called a levee, has been formed on each side of the river, from the lowest settlement to Baton Rouge. The principal embankment extends from the upper part of the island of New Orleans to Fort Plaquemines, a distance of 180 miles. Some few miles above New Orleans, where the force of the current is considerable, this embankment is thirty feet at the base, six on the summit, and fifteen high; but, in general, it does not exceed twelve at the base, and five in height. During the rise of the river the pressure against this bank has sometimes occasioned a disruption. The last instance occurred six miles above New Orleans, on the plantation of Mr M'Carty, in May 1816, where the waters forced an opening 140 yards broad, which admitted the escape of a volume of water six feet deep. In some places the Mississippi has changed its bed. At a great bend, twelve leagues below the mouth of Red river, some Canadians opened a gut, through which the waters poured with such impetuosity as to form a new and shorter channel by fourteen leagues; and the former lost all its waters except during the period of annual inundation. Navigation.-Ships ascend to New Orleans, and discharge their cargoes on the banks. Schooners go as high as Natchez. The common progress of a boat in ascending is five leagues per day. Vessels are sometimes lost by running against the extremity of drifted trees, which rise and sink with the motion of the water, their roots adhering to the muddy bottom.

Red river, which has its source in Mexico, in the Cordilleras chain of mountains, north-east of Santa Fe, which separates its waters from those of the Rio del Norte, receives several streams from 80 to 150 miles in length, before it enters Louisiana, and afterwards meandering in a south-eastern direction, it is joined by the rivers Bodeau, Dascheet, Black Lake, and Saline, in its course to the Mississippi, which it enters just below the 31st degree of latitude. The valley which this river traverses is described to be 800 miles in length, and 15 in breadth. The general width of the river is nearly 100 yards. Its mouth is between 400 and 500, but it gradually contracts to 300 and 250. A chain of lakes extends from the 33d degree of latitude, where it enters the state, as low as the S2d, the beds of which being nearly on a level with that of the river, their waters, according to their difference of elevation, flow alternately into each other. The course of the river, fifty miles from its outlet, is through a low marshy level, and at the distance of twenty-seven miles it approaches within three of the Mississippi, and runs nearly in a parallel direction to the junction. The intervening surface, during the swell of the waters in spring, is completely inundated, with the exception of some small spots as far as the Avoyelles, and even between this and the rapids, more than 100 miles from its mouth. The waters accumulate in some parts to the height of fifty

* In 37° north latitude, and 105° west longitude from Green

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or sixty feet. This river is navigable 1500 miles from its outlet, but the navigation is obstructed in two places. 1. By the rapids in 31° 21', 185 miles from its mouth, formed by two ledges of soft rock, extending across the channel at the distance of three quarters of a mile from each other. Loaded boats cannot pass when the water is low, but when high the rocks form no obstruction. 2. By rafts, commencing 300 miles above Natchitoches, and extending nearly 50 miles in length, formed of heaps of drifted wood, intermixed with vegetable earth, and in some places so compact that trees grow on them, and men and horses cross without danger. There is a passage for boats of ninety miles extent through the adjoining lakes and bayous. Its most considerable branches are the Bodeau, the Dascheet, the Black Lake river, and the Saline river, all on the north side, and the Black river on the same side, which joins Red river near the Mississippi. Black river is formed of three great branches which come from the Missouri territory in a southern direction ; the Ouachita, Ocatahoola, and Tensaw. The Ouachita branch, which rises in the high meadows near the 34th parallel of latitude, between the Red and Arkansaw rivers, passes through the Ouachita valley, receiving on the west the Derbane, a fine stream about sixty miles in length, and navigable for large boats thirty miles; and on the east the Barthelemy, which falls in three miles below the Derbane, on the opposite side, after a southern course of more than 100 miles. The banks of the Barthelemy are high, and not subject to be overflowed, but it communicates with

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