Once more I am floating upon the "Father of rivers." New-Orleans, with its crowd of "mingled nations", is seen indistinctly in the distance. We are now doubling a noble bend in the river, which will soon hide the city from our sight; but scenes of rural enchantment are opening before us as we advance, which will amply and delightfully repay us for its absence.

What a splendid panorama of opulence and beauty is now spread out around us! Sublimity is wanting to make the painting perfect—but its picturesque effect is unrivalled.

Below us a few miles, indistinctly seen through the haze, a dense forest of masts, and here and there a tower, designate the emporium of commerce—the key of the mighty west. The banks are lined and ornamented with elegant mansions, displaying, in their richly adorned grounds, the wealth and taste of their possessors; while the river, now moving onward like a golden flood, reflecting the mellow rays of the setting sun, is full of life. Vessels of every size are gliding in all directions over its waveless bosom, while graceful skiffs dart merrily about like white-winged birds. Huge steamers are dashing and thundering by, leaving long trains of wreathing smoke in their rear. Carriages filled with ladies and attended by gallant horsemen, enliven the smooth road along the LevÉe; while the green banks of the LevÉe itself are covered with gay promenaders. A glimpse through the trees now and then, as we move rapidly past the numerous villas, detects the piazzas, filled with the young, beautiful, and aged of the family, enjoying the rich beauty of the evening, and of the objects upon which my own eyes rest with admiration.

The scene has changed. The moon rides high in the east, while the western star hangs trembling in the path of the sun. Innumerable lights twinkle along the shores, or flash out from some vessel as we glide rapidly past. How exhilarating to be upon the water by moonlight! But a snow-white sail, a graceful barque, and a woodland lake—with a calm, clear, moonlight, sleeping upon it like a blessing—must be marshalled for poetical effect. There is nothing of that here. Quiet and romance are lost in sublimity, if not in grandeur. The great noise of rushing waters—the deep-toned booming of the steamer—the fearful rapidity with which we are borne past the half-obscured objects on shore and in the stream—the huge columns of black smoke rolling from the mouths of the gigantic chimneys, and spangled with showers of sparks, flying like trains of meteors shooting through the air; while a proud consciousness of the power of the dark hull beneath your feet, which plunges, thundering onward—a thing of majesty and life—adds to the majesty and wonder of the time.

The passengers have descended to the cabin; some to turn in, a few to read, but more to play at the ever-ready card-table. The pilot (as the helmsman is here termed) stands in his lonely wheel-house, comfortably enveloped in his blanket-coat—the hurricane deck is deserted, and the hands are gathered in the bows, listening to the narration of some ludicrous adventure of recent transaction in the city of hair-breadth escapes. Now and then a laugh from the merry auditors, or a loud roar from some ebony-cheeked fireman, as he pitches his wood into the gaping furnace, breaks upon the stillness of night, startling the echoes along the shores. What beings of habit we are! How readily do we accustom ourselves to circumstances! The deep trombone of the steam-pipe—the regular splash of the paddles—and the incessant rippling of the water eddying away astern, as our noble vessel flings it from her sides, no longer affect the senses, unless it may be to lull them into a repose well meant for contemplation. They are now no longer auxiliaries to the scene—habit has made them a part of it: and I can pace the deck with my mind as free and undisturbed as though I were in a lonely boat, upon "the dark blue sea", with no sound but the beating of my own heart, to break the silence. A few short hours have passed, and the grander characters of the scene are mellowed down, by their familiarity with my senses, into calm and quiet loneliness.

Having secured a berth in one corner of the spacious cabin, where I could draw the rich crimsoned curtains around me, and with book or pen pass my time somewhat removed from the bustle, and undisturbed by the constant passing of the restless passengers, I began this morning to look about me upon my fellow-travellers, seeking familiar faces, or scanning strange ones, by Lavater's doubtful rules.

Our passengers are a strange medley, not only representing every state and territory washed by this great river, but nearly every Atlantic and trans-Atlantic state and nation. In the cabin are the merchants and planters of the "up country;" and on deck, emigrants, return-boatmen, &c. &c. I may say something more of them hereafter, but not at present, as the scenery through which we are passing is too attractive to keep me longer below. So, to the deck. We are now about sixty miles above New-Orleans, and the shores have presented, the whole distance, one continued line of noble mansions, some of them princely and magnificent, intermingled, at intervals, with humbler farm-houses.

I think I have remarked, in a former letter, that the plantations along the river extend from the LevÉe to the swamps in the rear; the distance across the belt of land being, from the irregular encroachment of the marshes, from one to two or three miles. These plantations have been, for a very long period, under cultivation for the production of sugar crops. As the early possessor of large tracts of land had sons to settle, they portioned off parallelograms to each; which, to combine the advantages of exportation and wood, extended from the river to the flooded forest in the rear. These, in time, portioned off to their children, while every occupant of a tract erected his dwelling at the head of his domain, one or two hundred yards from the river. Other plantations retain their original dimensions, crowned, on the borders of the river, with noble mansions, embowered in the evergreen foliage of the dark-leaved orange and lemon trees. The shores, consequently, present, from the lofty deck of a steamer,—from which can be had an extensive prospect of the level country—a very singular appearance.

Farm-houses thickly set, or now and then separated by a prouder structure, line the shores with tasteful parterres and shady trees around them; while parallel lines of fence, commencing at these cottages, frequently but a few rods apart, extend away into the distance, till the numerous lines dwindle apparently to a point, and present the appearance of radii diverging from one common centre. A planter thus may have a plantation a league in length, though not a furlong in breadth. The regularity of these lines, the flatness of the country, and the fac simile farm-houses, render the scenery in general rather monotonous; though some charming spots, that might have been stolen from Paradise, fully atone for the wearisome character of the rest. We have passed several Catholic churches, prettily situated, surrounded by the white monuments of the dead. On our right, the lofty walls of a huge edifice, just completed, and intended for a university, rear themselves in the midst of a vast plain, once an extensive sugar plantation. This embryo institution is under state patronage. It is a noble brick building, advantageously situated for health, beauty, and convenience; and calculated, from its vast size, to accommodate a large number of students. It is to be of a sectarian character, devoted, I understand, to the interest of the Roman church.

A mile above, the towers and crosses of a pile of buildings, half hidden by a majestic grove of noble forest trees, attract the attention of the traveller. They are the convent du SacrÉ Coeur,—the nursery of the fair daughters of Louisiana. There are two large buildings, exclusive of the chapel and the residence of the officiating priest. The site is eminently beautiful, and, compared with the general tameness of the scenery in this region, romantic. A padre, in his long black gown, is promenading the LevÉe, and the windows of the convent are relieved by the presence of figures, which, the spy-glass informs us, are those of the fair prisoners; who, perhaps with many a sigh, are watching the rapid motion of our boat, with its busy, bustling scene on board, contrasting it with their incarcerated state, probably inducing reflections of a melancholy cast, with ardent aspirations for the "wings of a dove."The education of females is well attended to in this state; though the peculiar doctrines of the Roman Catholic church are inculcated with their tasks.

The villages of Plaquemine and Donaldsonville, the latter formerly the seat of government, are pleasant, quiet, and rural. The latter is distinguished by a dilapidated state-house, which lifts itself above the humbler dwellings around it, and adds much to the importance and beauty of the town in the eye of the traveller as he sails past. But the streets of the village are solitary; and closed stores and deserted taverns add to their loneliness. Between New-Orleans and Baton Rouge, a distance of one hundred and seventeen miles, the few villages upon the river all partake, more or less, of this humble and dilapidated character. Baton Rouge is now in sight, a few miles above. As we approach it the character of the scene changes. Hills once more relieve the eye, so long wearied with gazing upon a flat yet beautiful country. These are the first hills that gladden the sight of the traveller as he ascends the river. They are to the northerner like oases in a desert. How vividly and how agreeably does the sight of their green slopes, and graceful undulations, conjure up the loved and heart-cherished scenes of home!

We are now nearly opposite the town, which is pleasantly situated upon the declivity of the hill, retreating over its brow and spreading out on a plain in the rear, where the private dwellings are placed, shaded and half embowered in the rich foliage of that loveliest of all shade-trees, "the pride of China." The stores and other places of business are upon the front street, which runs parallel with the river. The site of the town is about forty feet above the highest flood, and rises by an easy and gentle swell from the water. The barracks, a short distance from the village, are handsome and commodious, constructed around a pentagonal area—four noble buildings forming four sides, while the fifth is open, fronting upon the river. The buildings are brick, with lofty colonnades and double galleries running along the whole front. The columns are yellow-stuccoed, striking the eye with a more pleasing effect, than the red glare of brick. The view of these noble structures from the river, as we passed, was very fine. From the esplanade there is an extensive and commanding prospect of the inland country—the extended shores, stretching out north and south, dotted with elegant villas, and richly enamelled by their high state of cultivation. The officers are gentlemanly men, and form a valuable acquisition to the society of the neighbourhood. This station must be to them an agreeable sinecure. The town, from the hasty survey which I was enabled to make of it, must be a delightful residence. It is neat and well built; the French and Spanish style of architecture prevails. The view of the town from the deck of the steamer is highly beautiful. The rich, green swells rising gradually from the water—its pleasant streets, bordered with the umbrageous China tree—its colonnaded dwellings—its mingled town and rural scenery, and its pleasant suburbs, give it an air of quiet and novel beauty, such as one loves to gaze upon in old landscapes which the imagination fills with ideal images of its own.

The scenery now partakes of another character. The rich plantations, waving with green and golden crops of cane, are succeeded here and there by a cotton plantation, but more generally by untrodden forests, hanging over the banks, which are now for a hundred miles of one uniform character and height—being about twenty feet above the highest floods. Now and then a "squatter's" hut, instead of relieving, adds to the wild and dreary character of the scene. This class of men with their families, are usually in a most wretched and squalid condition. As they live exposed to the fatal, poisonous miasma of the swamp, their complexions are cadaverous, and their persons wasted by disease. They sell wood to the steamboats for a means of subsistence—seldom cultivating what little cleared land there may be around them. There are exceptions to this, however. Many become eventually purchasers of the tracts on which they are settled, and lay foundations for fine estates and future independence.

Loftus's height, a striking eminence crowned by Fort Adams, appears in the distance. It is a cluster of cliffs and hills nearly two hundred feet in height. The old fort can just be discerned with a glass, surmounting a natural platform, half way up the side of the most prominent hill. The works present the appearance of a few green mounds, and though defaced by time, still bear evidence of having been a military post. The position is highly commanding and romantic. The scenery around would be termed striking, even in Maine, that romantic land of rocks, and cliffs, and mountains. A small village is at the base of the hills, containing a few stores. Cotton is exported hence, and steamers are now at the landing taking it in.

As we were passing the place on our way up the river, a white signal was displayed from a pole held by some one standing on the shore. In a few moments we came abreast of the fort, and in obedience to the fluttering signal, our steamer rounded gracefully to, and put her jolly boat off for the expected passengers. The boat had scarcely touched the bank, before the boatmen at one leap gained the baggage which lay piled upon the LevÉe, and tumbling it helter-skelter into the bottom of the boat, as though for life and death, called out, so as to be heard far above the deafening noise of the rushing steam as it hissed from the pipe, "Come gentlemen, come, the boat's a-waiting." The new passengers had barely time to pass into the boat and balance themselves erect upon the thwarts, before, impelled by the nervous arms of the boatmen, she was cutting her way through the turbid waves to the steamer, which had been kept in her position against the strong current of the river, by an occasional revolution of her wheels. The instant she struck her side the boat was cleared immediately of "bag and baggage," at the "risk of the owners" truly—and the hurrying passengers had hardly gained a footing upon the guard, before the loud, brief command, "go ahead," was heard, followed by the tinkling of the engineer's bell, the dull groaning of the ponderous, labouring engine, and the heavy dash of the water, as strongly beaten by the vast fins of this huge "river monster."