sissippi, which are but two or three feet above the common tide water near its mouth, gradually ascend with the plain of which they con. stitute the highest ridges, to the 33d degree of north latitude, where they are elevated above the low water mark of the river thirty or forty feet. The banks are, howe. ver, subject to be overflowed throughout this distance, except at those points protected by levees or embankments; this arises from a law incident to running water courses of considerable length, which is, that the floods in them acquire their greatest elevation as you approach a point nearly equidistant from their mouths and sources. The depth of the Mississippi is from 120 to 200 feet, decreasing as you approach very near the mouth, to a moderate depth. Exclusive of a number of small bayous, there are three large natural canals or channels, by which the surplus waters of the Mississippi are taken off to the gulf. The first of these above New-Orleans, is Lafourche, which, leaving the river at Donaldsonville, reaches the gulf in a tolerably direct course of about ninety miles. The La. fourche is about 100 yards wide; its bed is nearly on a level with the low water mark where it leaves the river; its banks are high, and protected by slight levees; and in high floods it takes off a large column of water. Above Lafourche the Bayou Manchac, or Iberville, connecting with the lakes Maurepas and Ponchartrain, takes off into the gulf, through the Rigoletts and other passes, a considerable portion of the surplus waters of the Mississippi; the bed of this bayou is 14 feet above the level of the low water of the Mississippi, and as it reaches tide water in a much

shorter distance than the Mississippi itself, it would take of a large column of water if its channel was not very much obstructed.* Nearly opposite to Manchac, but lower down the river, is Bayou Plaquemine, a cut off from the Mississippi to the Chafalaya; but as there is a considerable declination, in this part of the plain, of the alluvial lands, and being unobstructed in its passage, it is rapid, and takes off a large body of water; where it leaves the river, however, its bed is five feet above the level of the low water mark. About 88 miles above Manchac, and just below the 31st degree of latitude, is the Chafalaya. This is one of the ancient channels of the Mississippi river, and being very deep, carries off at all times great quantities of water; and were its obstructions removed, it would probably carry off a much larger quantity. As the distance from the point where the Chafalaya leaves the Mississippi, along its channel, to the gulf, is only 132 miles, and that which the Mississippi traverses from the point of separation to the gulf is 318, it is evident that a given column of water may be passed off in much less time through the channel of the latter stream. From this topographical description of that portion of the plain south of the 31st degree of latitude, it is evident, that, independent of the general and gradual declination of this plain descending with the Mississippi, it also has a more rapid declination towards the Lakes Maurepas and Ponchartrain on the east, and to

*The difference between the highest elevation of the waters at the afflux of the Manchac, and the lowest level of the tide in Ponchartrain, is from 27 to 80 feet.

wards the valley of the great Lake of Attakapas on the west, and it may, as to its form and configura. tion, be compared to the convex surface of a flattened scollop shell, having one of its sides very much curved, and the surface of the other somewhat indented; there is, therefore, good reason to believe that, by conforming to the unerring indications of nature, and aiding her in these operations which she has commenced, this plain may be reclaimed from inundation.

The quantity of water which has been drawn off from the Mississippi, through the Iberville, the Bayou Lafourche and the Chafa. jaya, has so reduced the volume of water which passes off through the Mississippi proper, that individual enterprise has been enabled to throw up embankments along the whole course of that river, from a point a little below that where the Cafalaya leaves the Mississippi nearly to its mouth, and for forty or fifty miles on each side of the Lafourche; the lands thus reclaimed will not, however, average forty acres in depth, fit for cultivation, and may be estimated at 400,000 acres. This is certainly the most productive body of land in the United States, and will be in a very short period, if it is not at present, as productive as any other known tract of country of equal

extent.

If the waters drawn off in any given time from the Mississippi through the natural channels, now formed, were delivered into the gulf through those channels in the same given time, then they would not overflow their natural banks, and the adjacent lands would be reclaimed; but this is not the fact; and the object can only be accom

plished by increasing the capacity and number of outlets of the natural channels by which the water is now disembogued, and by forming other artificial ones, if necessary, by which the volume of water that enters into the lower plain of Loui. siana, in any given time, may be discharged into the gulf of Mexico within the same time. If that volume were ascertained with any tolerable degree of accuracy, then the number and capacity of the chan. nels necessary for taking it off into the gulf might be calculated with sufficient certainty. A reference to the map of that country will show that the rivers which discharge themselves into the lower plain of Louisiana, and whose waters are carried to the gulf in common with those of the Missis. sippi, drain but a small tract of upland country; for Pearl river, and, if necessary, at a very mo. derate expense, the Teche, may be thrown into the ocean by sepa. rate and distinct channels.

At the thirty-first degree of north latitude, and near to the point where Red river flows into, and the Chafalaya is discharged from, the Mississippi, the waters of that river are compressed into a narrower space than at any other point below the 33d degree of north latitude; this may be considered as the apex of the lower plain. The contraction of the waters of the Mississippi at this point is occasioned by the Avoyelles, which, during high water, is an island, and is alluvial land, but of ancient origin; from this island a tongue of land projects towards the Mississippi, which, though covered at high water, is of considerable elevation. It is probable, therefore, that at the point thus designa.

ted, a series of experiments and admeasurements could be made, by which the volume of water discharged in any given time, on the lower plain, by the Mississippi, at its different stages of elevation, might be ascertained with sufficient accuracy to calculate the number and capacity of the channels necessary to discharge that volume of water into the gulf of Mexico in the same time. With this data, the practicability and the expense of enlarging the natural, and excavating a sufficient number of new, channels to affect this object, might readily be ascertained. If that work could be accomplished by the government, every thing else in respect to the lower plain should be left to individual exertion, and the lands would be reclaimed as the increase of popula tion and wealth of the country might create a demand for them.

The contraction of the plain of the Mississippi by the elevated lands of the Avoyelles, and the manner in which Red river passes through the whole width of the upper plain, to a distance of nearly thirty miles, has a strong tendency to back up all the waters of the upper plain; therefore it is that, immediately above this point, there is a greater extent of alluvial lands, more deeply covered with water than at any other point, perhaps, on the whole surface of the plain of Louisiana; and at some distance below this point, the embankments of the Mississippi terminate. To enable individuals to progress with these embankments, and to facilitate the erection of others along the water courses, and to reclaim with facility the lands of the upper plain, it will probably be found to be indispensably necessary to draw

The

off a considerable portion of the water by artificial channels. Red river, arrested in its direct progress by the elevated lands of Avoyelles, is deflected in a direction contrary to the general course of the Mississippi, and traverses the whole width of the upper plain in a circuitous course of upwards of thirty miles before it reaches that river. There is good reason to believe that the waters of the Red river, or a very large portion of them, in times past, found their way through Bayou Boeuf and the lake of the Attakapas to the ocean; and during high floods a small portion of the waters of that river arc now discharged into the Bayou Bœuf, at different points between the Avoyelles and Rapide. A deep cut from the Red river, through the tongue of elevated alluvial land east of the Avoyelles, to the Chafalaya, and opening the natural channels by which it now occasionally flows into the Bayou Boeuf, would probably take off the waters which accumulate at the lower termination of the upper plain with such rapidity, and reduce their elevation so much as to enable individual enterprise and capital to continue the embankments, which now terminate below this point, not only along the whole course of the Mississippi, but along all those extensive water courses running through the upper plain.

The Tensa, a continuation of Black river, is, for fifty miles above its junction with Red river, a deep water course, and in breadth but little inferior to the Mississippi. It draws but a very small portion of its waters from the high lands, but com. municates with the Mississippi by a number of lakes and bayous, ai different points, from near its

mouth to its source, which is near the 33d degree of latitude, and through these channels aids in drawing off the surplus water of the Mississippi, while it continues to rise; when the Mississippi, however, retires within its banks, the waters in these bayous take a different direction, and are returned through the same channels into the Mississippi. Particular local causes will produce this effect at particular points; but the general cause, so far as these bayous connect with the Tensa, will be found in the fact that there is not a sufficient vent for the waters of the upper plain at the point of connexion with the lower plain of Louisiana.

The

Tensa is also connected, in times of high water, at several points, with the Washita and its branches. When the Mississippi has risen to a point a few feet below its natural banks, the whole of the upper plain of Louisiana is divided by the natural channels which connect the Mississippi with the Tensa, and the Tensa with the Washita, into a number of distinct islands of various extent. The banks of the rivers and the natural channels which connect them are very ge. nerally the most elevated lands; and each and all these islands might be reclaimed from inundation by embankments, thrown entirely around them, of from six to twelve feet high, provision being made to take off the rain water, and that occasioned by leakage and accidental crevices in the banks, with machinery. While the Mississippi is rising, the waters are carried off through these natural channels and their outlets into the lakes and the lowest and most depressed parts of the plain. During this process, there are currents and

counter currents in every possible direction; but when the floods have attained their greatest known height, then this whole plain becomes covered with water, from a few inches to twelve feet deep, as its surface may be more or less depressed; and if it could be exposed to view, would exhibit the appearance of an immense lake, with a few insulated spots dispersed throughout it, such as the island of Sicily, the banks of the lakes Concordia, Providence, and Washington, and some very narrow strips partially distributed along the banks of the Mississippi and the other water courses. If the whole of the upper plain were reclaimed in the manner above mentioned, then the waters being contracted into much narrower channels would necessarily be very considerably elevated above the point to which they now rise; and passing off on the lower plain with greater elevation and greater rapidity, and having only the present natural channels of outlet to the gulf, the inevitable consequence would be, that the whole of the lower plain would be inundated, and probably parts of Attakapas and Opelousas would again be subject to inundation.

The reclamation of both the plains of Louisiana will depend, under any possible plan that may be proposed, upon the practicability of tapping the Mississippi and Red rivers, at one or more points, and to an extent that may draw off rapidly such a quantity of water as will prevent the refluent waters now collected just above the 31st degree of latitude, from rising to the heights to which they now do, and the practicability of delivering the waters into the ocean within periods equal to those in which they

were drawn off. We have seen that the natural channels of the Lafourche, Plaquemine, Iberville, and the Chafalaya, have so reduced the mass of water in the Mississippi, below their points of afflux, as to enable individuals, by very moderate embankments, to confine that part of the Mississippi within its banks. The Lafourche is the only one of these natural channels that takes off the waters to the ocean so rapidly and directly as to enable individuals to erect levees or embankments along its whole course. The passes of the Rigolets, and at Berwick's bay, not being sufficient to take off the waters which flow through them as fast as they are discharged into their resevoirs, it is evident that no beneficial effect could be derived from tapping the Mississippi at any point on its eastern bank, or at any point on the Western bank above the Lafourche, unless the capacity of the outlets at Berwick's bay and the Rigolets be greatly enlarged. The passes at the Rigolets are well known; and it is probable that by enlarging them, and cutting off that portion of the waters of Pearl river which now flows through them, they might be made adequate to take off, in a sufficiently short period, the waters of Iberville and those of the short rivers of Beliciana, so as to prevent that portion of the plain between the Iberville and the city of New-Orleans from being inundated, except so far as the waters of Ponchartrain, elevated by high winds and tides, may produce that effect. It is only, therefore, on the west bank of that river, or the south bank of Red river, that the proposed tappings can be made with the prospect of a successful issue.

The course of the Mississippi from Donaldsonville to New-Orleans being nearly parallel to the gulf, and the distance to the gulf across that part of the plain being much shorter than that by its natu ral channel to tide water, that portion of the river presents eligible points for tapping, particularly near to New Orleans; the commerce of which, in time not perhaps distant, may require a deep cut to be made to the gulf. The width of the river

at

Donaldsonville being about seven hundred yards, the rise above its natural banks about one yard, and its velocity two and a half miles an hour; if, then, by one or more tappings below this point, a volume of water of the above dimensions could be carried off to the ocean with equal velocity, then would the highest elevation of the river be reduced very considerably every where below such tapping, and for some distance above. Such a reduction of the elevation of this part of the river, aided by the clearing out of the rafts from the Chafa. laya, would possibly produce so great a reduction of the refluent waters at the junction of the Red and Mississippi rivers, as to enable individuals to proceed gradually to the reclamation of the whole of the upper plain by common embank. ments. It would then require only an increased capacity to be given to the outlets of the lake of Attakapas, to insure the reclamation of both plains. But if this effect cannot be produced by the tappings below the Lafourche, then they must be made at points higher up, either between Plaquemine and the Chafalaya, or at a point about the mouth of the Bayou Lamourie, or Du Lac, on Red river. A reference to the map will show that