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AS soon as we pass beyond the narrow borders of the Nile valley we encounter the Desert. Egypt is, in fact, the Nile; the Nile makes, recreates, preserves, fecundates Egypt, which, without this grand and ever-famous river, would immediately cease to be.

“Everything in Egypt,” says Miss Martineau,[50] with equal truth and eloquence, “life itself, and all that it includes, depends on the state of the unintermitting conflict between the Nile and the Desert. The world has seen many straggles; but no other so pertinacious, so perdurable, and so sublime as the conflict of these two great powers. The Nile, ever young, because perpetually renewing its youth, appears to the inexperienced eye to have no chance, with its stripling force, against the great old Goliath, the Desert, whose might has never relaxed from the earliest days till now; but the giant has not conquered it. Now and then he has prevailed for a season, and the tremblers whose destiny hung on the event have cried out that all was over; but he has once more been driven back, and Nilus has risen up again to do what we see him doing in the sculptures—bind up his water-plants about the throne of Egypt.”

The traveller, ascending the famous river which has so long been mixed up with an apparently insoluble geographical problem, sees the Desert everywhere present; its yellow boundary-line is vividly traced against the rich emerald-green of the fertile valley, and, as he advances, that line seems to draw nearer and nearer, until the cultivated soil appears reduced to a narrow strip on the river-bank. It has encroached upon many once prosperous and busy sites, and buried deeply the memorials of the old Egyptian civilization.

“Round the decay

Of that colossal wreck, boundless and bare,

The lone and level sands stretch far away.”

Everywhere outside the valley of the Nile, I repeat, lies the Desert. West of the Arabian chain of heights stretch the vast sandy plains frequented by the Arab tribes of the Beni-Wassel and the Arabdé. Beyond the eastern chain spread the Libyan Deserts, which, in the remote distance, merge into the Great Sahara, and those of the Thebaïd, where the early Christian anchorites found a dismal asylum. Lower, to the south of Egypt, extend the Deserts of Lower Nubia.

Let us ascend the Nile as far as Korosko, on the right bank of the river, and cross the huge chain of rocky hills which separates the cultivated zone from the Desert to which the village just spoken of gives name. These hills, all of equal elevation, assume the form of truncated cones. They are layers of granite superimposed horizontally, and with a depth of colour which makes them resemble at the first glance masses of basalt. They are absolutely bare, and separated from each other by abrupt sinuous gorges, whose bottom is covered deep in sand of golden lights, brought from the desert on the wings of the south-west. Long streams of the same brilliant sand descend the slopes opposed to the direction of the wind with graceful undulations, which subside imperceptibly in the blown sand that carpets the floor of these mysterious valleys. The crests of the hills can only be distinguished by their different colours; some are lightly shaded with gray, others with blue or green, and others again with rose or crimson. The reflets of the setting sun on these uniform and many-coloured summits have a marvellous splendour, lighting up the scene until it assumes a fairy aspect,

“And all puts on a gentle hue,

Hanging in the shadowy air,

Like a picture rich and rare.”

At certain times it would rather remind the spectator of another of Coleridge’s conceptions:

“A savage place! as holy and enchanted

As e’er beneath a waning moon was haunted

By woman wailing for her demon-lover!”[51]

Yet the spectacle is generally one of a rare and peculiar loveliness. “If nature,” says M. Trémaux,[52] “had invested with this kind of beauty our verdurous fields of the West, they would have been veritable Edens; but to produce, blend, and harmonize these inimitable hues, it requires, under the last beams of the sun, the emanations from the heated sands and those which the day has called into existence from the burning surfaces of the denuded rocks. It is by the side of her greatest horrors nature places her grandest beauties.”

The horror of the Desert does not lie only in its aridity, in its vacuity—this vacuity is not absolute; in default of life, Death peoples its solitudes. The glens or gorges frequented by the caravans are lined with stones, symmetrically disposed at certain intervals. These stones mark the places where rest the remains of the hapless pilgrims who have attempted to cross the wilderness, and perished in the attempt. Round and about each rugged tomb lie the skeletons of animals which none have troubled themselves to bury in the sand. Frequently you may see, on the sandy wastes of Africa, or the desolate plains of Asia and the New World, these carcasses laid out in two interminable rows; indicating the gloomy track which should be followed by the traveller, and never failing to remind him of the tribute Death levies upon mankind in these accursed regions. Thus does the Desert show itself more relentless than even the hungry ocean, which at least devours its victims whole, and affronts the eye with no traces of its murders. But the Moloch of the Desert has no shame; it cynically exposes the hideous remains of those whom it has killed; it strews the earth with their bones; it has its museums of skeletons, or rather of preserved animals.

M. Trémaux observed this curious phenomenon in the ravines of Korosko, but it probably occurs elsewhere under similar conditions. On closely examining the carcasses which he met at every step, he was astonished to find them covered with their skin, and presenting still their natural forms, as if the animals had been stuffed or embalmed. He readily distinguished horses, oxen, asses, camels. He observed with no less surprise that these corpses exhaled no odour. They had been dried by the heat before decomposition could commence its frightful work. The skin had hardened; the muscles and internal organs had been reduced into dust and gradually blown away by the wind through the yawning apertures at the two extremities of the body. There remained nothing more, literally, but skin and bone.

“This skin had such a consistency,” says our author, “such a degree of solidity, that all my efforts to split it were without result. The heaviest stones which I could raise rebounded upon their carcasses with a loud noise, but did not pierce them. If a man dies while a caravan is on its march, he is buried in the sand. I have had no opportunity of examining whether the desert-heat produces the same effect upon his body as upon the corpses of the animals just mentioned; but it ought not to be so, since the human skin has not the same consistency.”

On issuing from these gorges, we enter upon the Desert proper by a sandy plain which the Djellahs have named the “River without Water,” and which, very low at first, slowly rises into a plateau of very slight elevation, intersected by some veins of a sandstone similar to that of the conical mountains. Then the plain declines anew, and we emerge upon the Sea of Sand, where the pulverized sandstone alternates with fields of rotted or broken pebbles, and mounds of porphyry and granite. At the foot of one of these mounds, the Tallat-el-Guindé, flourish a few wretched vegetables, among others some gum-trees and doum-palms. The latter trees are also found in solitary mournfulness scattered about the plain. Otherwise the Desert of Korosko is wholly deprived of vegetable life, of

“The glory in the grass, and the splendour in the flower.”

As for water, it must needs be content with that of a few brackish wells, grouped, about twelve in number, at a spot called El-Mourath. It is there only that the caravans can fill their ill-tanned leather-bottles, in which the already nauseating liquid grows hot, and quickly becomes putrid. Its stench and its taste are then so disgustful that the very camels reject it several times before they can constrain themselves to drink of it.

Ravines of Korosko.

The Desert of Bahiouda, situated in about the same latitude as that of Korosko, but on the other bank of the Nile, is of a less absolute aridity and nakedness. Water is more abundant and less brackish; vegetation is less scanty; and one meets on every side with giraffes, gazelles, wild cattle, and even, it is said, with lions and elephants. Great numbers of reptiles, lizards, serpents, and tortoises inhabit the sand and the crevices of the rocks.

South of the above-named Deserts, towards 17° N. lat., is placed the limit of the Rainless District. Under the 18th parallel the rains do not last above one or two months in the year, and in some years are absolutely wanting; but when they do fall, it is generally in impetuous torrents. As we advance towards the Equator they become more regular, and last for longer periods. According to Humboldt, the average yearly rainfall in 19° N. lat. measures 80 inches; under the equator, 96 inches. In these tropical climes the year is divided into two seasons—one of excessive drought, and one of excessive rain. During the former, the sky is ever cloudless; during the latter, completely overcast.

There are, in fact, two rainless belts or districts, one on each side of the Equator. In the old world, the northern belt commences on the west side of Africa; includes the Sahara between 16° and 28° of latitude; and narrowing as it extends easterly, comprises on the banks of the Nile from 19° to 27°. It also embraces the low coast; and portions of the interior of Arabia; passes through Beloochistan to the base of the Himalayas, and terminates with the rainless tableland of Thibet. The southern district occurs north of the Gareep or Orange River in South Africa, and includes wide tracts in Australia, and a narrow belt in South America.

Where the earth is blessed with copious showers, vegetation will abound; grass, and herb, flower, bush, and tree;

“Fields of grain

Will bend their tops

To the numberless beating drops.”

To meet with the true Desert we must, therefore, direct our steps in a north-westerly course, and penetrate into The Sahara.

M. Charles Martins, in his elaborate monograph on this remarkable region, divides it into three distinct sub-regions: the Desert of the Table-lands, the Desert of Erosion, and the Sandy Desert.[53]

In Algeria, and in Barbary generally, the Mediterranean littoral does not come into immediate contact with the Sahara; but is separated from it by the Atlas chain. But the Atlas does not rise abruptly from the plain: on either side it ascends by a succession of rocky steps or terraces, which form the sub-region of the elevated Table-lands. Vast denuded surfaces, sprinkled with chotts, or salt lakes, deprived of all arborescent vegetation, traversed in summer by immense herds which feed on the plants even to their very roots, bare mountains starting abruptly from these horizontal surfaces; such is the general aspect of the landscape. The richly-varied culture of the Mediterranean littoral has disappeared, and barley is the only cereal which the husbandman relies upon for his harvest. At many points, however, the “purple vine” and “golden olive” succeed admirably, and are destined one day to clothe the nakedness of these plateaux which the free-pasturing herds and the careless Arab have stripped of their blooming verdure.

Descending these rocky terraces of gray old Atlas, we enter the desert region in its first phase: the Desert of the Table-lands, or Saharan Steppe.

LANDSCAPE IN THE ATLAS (REGION OF TABLE-LANDS).

Here, horizontal strata of mud and gypsum, or sulphate of lime, are deposited upon the shores, as it were, of the great Sandy Sea. The gypsum reposing on the mud is composed of plates in such close juxtaposition as to resemble an artificial pavement. “It covers the surface of vast plateaux which have not been encroached upon by the waters; whether those waters were marine currents at the epoch when the Sahara was a vast sea, or diluvian torrents which descended from the mountains after their elevation, little matters; the gypsum, produced by the violent evaporation of the Saharan sea, has withstood their operation, and composes the plateaux of which we are speaking. Their surface is so smooth, that vehicles might roll for leagues upon this natural pavement, which echoes like a vault under the horses’ hoofs. A plateau of this kind, the small Desert of Mourad, extends from Biskra to the banks of the great salt lake called Chott Mebrir by the Arabs. The gypseous surface is not everywhere exposed: most frequently it is covered by a layer of small rounded pebbles, nearly all quartzose, exhibiting the greatest variety of tints, from the purest white to the most vivid red; they are mixed with black calcareous stones split on the surface. Whence came these pebbles, which have evidently been ‘rolled’ by the waters? We know not. They are the mysterious witnesses of those grand diluvian torrents which have left the traces of their passage over the surface of the whole earth, though the geologist cannot always discover the mountains or rocks that furnished the materials of this diluvium.”[54]

From the Desert of the Table-lands we must needs make another descent. The town of Batna is situated at the extremity of the lowest of the Atlantean terraces, whose elevation is still some 3300 feet above the level of the sea. To the north-west rise the lofty spires of the colossal chain, with their diadems of cedars sharply defined in black upon the azure of the sky. Loftiest of all soars the Jebel-Tougour, or “Peak of Cedars,” reminding the spectator of the Pyrenean crests. Towards the south-east stretch the rounded shoulders of the mountains of the Aurès, clad with dense dark forest of oak and pine. In a fold of the mountains lurk the ancient Lambessa and the mouldering ruins of a Roman camp. Four miles to the south of Batna is a large depressed hill, whose base mingles with the table-land, above which it rises only three hundred and thirty feet. This ridge marks the watershed; all the streams on the north flowing towards the Mediterranean, and, on the south, gradually disappearing in the arid bed of the ancient Saharan sea. On the frontier line, like a Cyclopean landmark, is planted the Peak of Cedars, while from its loins a torrent issues, and through a deep ravine whirls and leaps and flows towards the desert. Springs, abundant and warm, bubble up through the chalky marls, and take the same direction. Beyond the French military post, called Les Tamarins, the road descends the ravine-cloven mountain-slopes, and passes over the torrent which bifurcates at the foot of the majestic Metlili. On the left is seen a steep wall of rock, the Jebel-Gaouss, cleft midway by a chasm, or breach, which the Arabs expressively designate “The Mouth of the Desert,” and which, gradually enlarging, opens upon the first oasis of the Sahara, El Kantara (“the bridge,” from a Roman arch which spans the torrent), the most northerly limit of the palm-tree. “A magnificent, semi-alpine, semi-tropical scene. Below, a tumultuous foaming stream, its banks on either side clad with palms bending their feathery foliage towards the river, and sheltering fig, apricot, peach, almond, and pomegranate trees.”[55] Above, a range of snowy heights, wreathed in ever ascending and descending clouds.

We now enter the Desert of Erosion, a mass of mountainous highlands; of ridges, peaks, and cols, intersected and, as it were, gashed by ravines where roll the winter torrents and the rivers which the heats of summer dry up, and which, hollowing and gnawing into the stony soil, spread themselves over the valleys and awake a transitory vegetation. The erosive action of the waters is, then, the special characteristic of this part of the desert, which the Arabs call Kifar, or “the abandoned country.” Most of the streams which water it have their sources in Mounts Aurès and Zibans, which form its northern boundary. They have excavated wide intermingling furrows, whose intervening spaces are occupied by gypseous plateaux. The formations of less resisting power, the marls, clays, and sands, have been washed away.

THE SAHARA (DESERT OF EROSION).

The waters, whether proceeding from rain, or the melting of the snows on the loftiest peaks, are very pure at first, and roll in deep beds with vertical sides; when they reach the plains, their channels grow wider and shallower. In the wet season, the floods burst the banks, and overflowing, carry down immense quantities of rolled pebbles, which are distributed over an extensive area; in ordinary weather they are reduced to thin threads of silver, which, on arriving in the desert, vanish completely. You must excavate the soil to obtain a supply of water, and when found, it is brackish. Frequently the beds unite, forming basins of greater or less extent and depth, which fill themselves at the close of the winter floods, and a few of which preserve, even in the winter season, a certain quantity of water. Elsewhere, the soil is only humid, thanks to the abundance of salt, which retains the moisture. In such places numerous slimy marshes occur, where the traveller may not adventure without peril. But in general the surface is dry, cracked, cloven, and completely parched.

The Desert of Erosion is not completely inhabited. At intervals you meet with a few squalid villages, and a multitude of camel’s-skin tents are scattered like black spots over the yellow or grayish plains, on the borders of the chotts or scanty water-courses. Herds of goats and flocks of sheep wander in the valleys, browsing on the rare short grass. Columns of smoke arise from the Arab bivouacs, and the women of the Sahara group themselves around the wells and springs to fill the water-bags with which they load their asses.

When, from the summit of the rocks which fence round and bristle over the Desert of Erosion, we perceive for the first time the Desert of Sand, the impression is very similar to that which we derive from the sight of ocean. M. Martins had already become sensible of this peculiar effect when, from the Col de Sfa, he had gazed down upon the Desert of the Plateaux. “A grand circular arch,” he says, “extended before us, bounding a violet surface, smooth as the sea, and blending at the horizon with the azure of heaven; it was the Sahara. The arc eastward rested against the chain of the Aurès; westward, against that of the Zibans, some of whose offshoots, in the neighbourhood of Biskra, arose like reefs upon that sea which seemed to have been frozen suddenly into immobility. The actual sea ever trembles and shivers on the surface; a light wavering, imperceptible to the eye, propels towards the shore the expiring wave, fringed with a border of foam. Here, nothing like this may be seen; it is a motionless, a congealed sea, or, rather, it is the smooth bed of a sea whose waters have disappeared. Science teaches us that such is the fact; and now as ever the expression of the reality is more picturesque, more eloquent than all the comparisons created by the imagination.”[56]

An eminent French artist, M. Fromentin, whose skill with the pen equals his talent with the brush, has also painted this “congealed sea” in grand and poetic language. “The first impression,” he says, “produced by this glowing lifeless picture, composed of the sun, space, and solitude, is keen, and cannot be compared to any other. Little by little, however, the eye grows accustomed to the grandeur of the lines, to the emptiness of space, to the denudation of the earth; and if anything can still astonish, it is that one becomes sensible to effects which change so little, and is so powerfully affected by spectacles in reality of the simplest character.”[57]

I must also enumerate among the “artists in words” who have painted the wonders of the Sahara, General Daumas, not one of the least distinguished of the Franco-Algerine warriors. He describes it in the following language:—“It is a naked and barren immensity,—this sea of sand, whose eternal waves, agitated to-day by the choub, will to-morrow be heaped up immovable, and which are slowly furrowed by those fleets called caravans.”

General Daumas, it is evident, confines himself to the scientific realism, which M. Martins prefers to the glowing and inexact imagery of the poets, and conveys in a few words an accurate yet very picturesque idea of that arid sea, where the wind stirs up rolling waves of sand instead of foaming billows, and which the Arabs call Falat. I shall place before the reader, however, the description given by M. Martins himself, for it represents both the ensemble and the details of the picture.

“If the Desert of the Plateaux,” he says,[58] “be the image of a sea suddenly fixed during a level calm, the Desert of Sand represents to us a sea which may have been solidified during a violent tempest. The Dunes, or sand-hills, like waves, rise one behind another even to the limits of the horizon, separated by narrow valleys which represent the depressions of the great billows of the ocean, all whose various aspects they simulate. Sometimes they narrow themselves into keen-edged crests, or shoot upwards in pyramids, or swell into cylindrical domes. Seen from a distance, these Dunes also remind us at times of the appearances of the névé (or granulated snow) in the amphitheatres and on the ridges which lie contiguous to the loftiest Alpine summits. Their colours still further enhance the illusion. Moulded by the winds, the burning sands of the desert assume the same forms as the névés of the glaciers.”

Whoever has seen the Dunes on the coast of Norfolk, or more particularly in Gascony, may gain a very accurate conception of the Desert. The only notable differences are in the extent, which here seems infinite, like that of ocean; the purity of the heaven, which is seldom sullied by a cloud; and the colour, which is of a soft, intense blue. The nature of the soil is the same; it is a very fine, shifting, silicious sand, white sometimes, like that of Fontainebleau, and sometimes reddened by the presence of oxide of iron. In the Sahara this sand gathers in veritable Dunes, hillocks which the wind upheaves, displaces, and transforms from one day to another. Only the lettes, or valleys, which in our Dunes receive the pluvial waters and preserve a sufficient amount of fertility, are here just moistened by rare saline infiltrations, and almost always remain in a condition of absolute sterility. Nevertheless, in some localities, the presence of gypsum gives the sand a certain fixity, which permits a small number of plants to germinate and develop themselves. This gypsum is never found but in the valleys, and never in tabular masses, as on the plateaux, but only in crystals of various forms, penetrated by silica. “You pick up a pebble,” says M. Martins, “and find it to be a crystal.” The villages are surrounded by crenellated ramparts built of crystals; the houses which compose these villages are constructed of the same materials; and very weird and splendid is the scene presented by these edifices with their sun-illuminated walls. Notwithstanding their small dimensions and mean architecture, when thus lit up in glorious radiance, they seem to realize the wonders told in fairy tales of the enchanted palaces of the genii!