Edward Heawood and Frank Richardson Cana

“ This sea was bounded on the north and east by the mountains of Air, Ahaggar, the Asjer Tasili, &c. An extensive acquaintance with Saharan characteristics shows, however, that a sea for the Sahara as a whole is impossible. Henri Schirmer, who in 1893 published an admirable summary of Saharan geography up to that date, argued that the desert nature of the Sahara is due to forces which have been at work for ages, although, as in all deserts, the dryness is probably progressively increasing. ”

“ There are also well-marked river-beds in the central Sahara. The Wadi Telemsi, rising in Adrar, of the Iforas, apparently joined the Niger near' Gao, while the Wadi Taffassassent, which rose in the Ahaggar mountains, is believed to have been the ancient upper course of the lower Niger. The oases are also proofs of the presence of a steady supply of underground moisture, for vegetation under the Saharan climate (beyond the few plants specially adapted to desert conditions) is exceptionally thirsty. ”

“ In the south are the Juf (depressions) , covering a vast area to the south-east of the middle portion of the Igidi, another area between the Adghagh plateau and the Ahaggar, and a third between Air and Tibesti. The Juf or depressions are not, except in rare instances, below sea-level. In the Libyan desert is a vast region of dunes of unascertained limits; the characteristics of the Libyan desert being thought typical of the whole of the Sahara originated the idea of “a sea of shifting sand” as descriptive of the entire desert. ”

“ The chief centres of population in the Sahara are, firstly, the oases, which occupy positions where the underground water makes its way to the surface or is readily reached by boring; and, secondly, certain mountainous districts where the atmospheric moisture is condensed, and a moderate rainfall is the result. ”

“ In the centre of the Sahara is a vast mountain region known as the Ahaggar (Hoggar) Tasili or plateau. The culminating peaks of this plateau. Mounts Watellen and Hikena, are about 900 m. in a straight line almost due S. of the city of Algiers and about 1200 m. due N. of the mouth of the Niger. They also occupy, speaking roughly, a central position between the Atlantic and the Nile. The Ahaggar plateau is not inferior to the Alpsnin area, but its highest peaks do not greatly exceed 8000 ft. They are believed to be volcanic like those of Auvergne. ”

“ Northwest of Timbuktu in the district or “Kingdom” of Biru is the oasis and town of Walata, a Tuareg settlement. Other mountainous districts in which a certain amount of rain falls regularly, and which contain a population above the average for the Sahara, are Tibesti and Borku, in the east centre, and Adrar in the west. Tibesti and Borku are peopled by Tibbus; the western Adrar by Moors (Berbers) . The northern portions of the Sahara are inhabited by nomad Arabs. ”

“ Experiments carried out by the French at Ain Sefra, on the northern border of the desert, have shown that by protecting the sand from the action of the wind by a litter of alfa grass, time is given for the establishment 'of suitable trees, which include the tamarisk, acacia, eucalyptus, prickly pear, peach and aspen poplar, the last-named having proved the most capable of all of resisting the desert conditions. ”

“ The physical characteristics, and especially the dark colour, of many of the Saharan populations is apparently, a stronger argument, but even this is capable of another explanation. Caravans of negro slaves from time immemorial passed northwards along the main desert routes, and it is just in the oases on these routes that the dark element in the population is chiefly found. ”

“ Although now mainly waterless, the Sahara possesses the skeleton of a regular river-system. From the north side of the Atakor-’n-Ahaggar, through which runs the “water-parting” Skeleton river-systems. between the basins of the Mediterranean and Atlantic, system begins Wadi Igharghar, Which, running northwards between the Tasili plateau and the, Irawen mountains, appears to lose itself in the sands of the Eastern Erg, but can be traced northwards for hundreds of miles. ”

“ Wide areas like the arid stony plateaus (hammada) must be abandoned as hopeless.
As already stated, the popular conception of the Sahara as a sand desert is erroneous. It IS really a stony, wind-swept waste with much bare rock visible, the actual 'area of pure sand forming a relatively small portion. A broad belt of Archaean rocks extends throu hout the desert, appearing at intervals in the form of hills and plateaus from beneath, the superficial sands and Quaternary deposits. Examples are the granite of Air and the gneiss and mica-schists of this massif and of the Ahaggar plateau. ”

“ The hope of an eventual commercial exploitation of the Sahara rests mainly on the possible existence of mineral wealth. To supply easy communication between Algeria and Nigeria the construction of a railway across the desert has found many advocates. Two principal routes have been suggested, the one taking an easterlyTrans-Saharan Railway Schemes. line from Biskra through Wargla to Air (Agades) and Zinder—generally, the route followed by Foureau (see below) ; the other starting from the terminus of the most westerly railway already existing, and reaching Timbuktu via Igli and the Tuat oases. ”

“ The commerce of the Sahara is not inconsiderable. Among the more important trade routes are (1) from Morocco to Cairo by Insalah and Ghadames, which is followed by the commerce pilgrims of western Africa bound for Mecca; this route has been largely superseded by the sea route from Tangier to Alexandria; (2) from Kuka (Lake Chad) to Murzuk and Tripoli;Commerce. (3) from Kano and Zinder to Tripoli by Air and Ghat; (4) from Timbuktu to Insalah, Ghadames and Tripoli; (5) from Timbuktu to Insalah and thence to Algeria and Tunisia; (6) from Timbuktu to Morocco. ”

“ There is only one known route through this dreadful wilderness—one running north and south to the oases of Kufra, which lie in its centre. The dunes in the Libyan desert, so far as is known, run N.N.W. and S.S.E. In the Eastern Erg the dunes also lie in long lines in a N.N.W. and S.S.E. direction, presenting a gradual slope to windward and an abrupt descent to leeward. There they are generally about 60 or 70 ft. high, but in other parts of the Sahara they are said to attain a height of upwards of 300 ft. ”

“ The primary cause is to be sought in the existing distribution of land and sea, the great land mass of North Africa causin an outflow of air in all directions (and consequent absence of rain) in winter, and an in draught in summer, when the surface is intensely heated and the relative humidity of the atmosphere becomes so small that condensation is all but impossible. The vicinity of the comparatively cool Mediterranean in the north accentuates the force of the winds from that direction, which, blowing towards a lower latitude, are in their v nature dry winds. ”

“ In 1890 Foureau—who in 1883 had undertaken a first journey of exploration south of Wargla—reached the Tademayt plateau in 28° N., fixing the position of 35 places, and in 1892–1893 came the first of his long series of expeditions undertaken with a view of penetrating the country of the Azjer Tuareg, the powerful confederacy which lay on the route to Air and Lake Chad, never traversed in its entirety by a European. ”

“ Instead of being a boundless plain broken only by wave-like mounds of sand hardly more stable than the waves General aspect. of ocean, the Sahara is a region of the most varied surface and irregular relief, ranging from 100 ft. below to 5000 and 6000 and even in isolated instances to 8000 ft. above the sea-level, and, besides sand-dunes and oases, containing rocky plateaus, vast tracts of loose stones and pebbles, ranges of the most dissimilar types, and valleys through which abundant watercourses must once have flowed. ”

“ It is impossible to ascertain the extent of the knowledge of the Sahara possessed by the ancients. The Egyptians penetrated the Libyan and Nubian deserts at points, and Carthaginians and Phoenicians were acquainted with the northern fringe of the desert in the west. European exploration Exploration.dates from the beginning of the 19th century. In 1819 Captain G. F. Lyon and Joseph Ritchie penetrated from Tripoli to Murzuk, where Ritchie died. ”

“ Except in the southCentres of population. of Algeria, where cultivation has been extended by means of artesian wells, the condition of the Sahara oases is far from prosperous. Prior to the French occupation, a feeling of insecurity had been engendered by the marauding habits of the nomad tribes; cultivation had become more restricted; and the decline of the caravan trade had brought ruin to certain centres, such as Murzuk. The most important are the oases of the Tuat region, especially Insalah; those of Ghat and Ghadames on the route from Tripoli to Zinder ”

“ From December to March wheat, barley and other northern grain crops are successfully cultivated, and in the hotter season rice, dukhn, durra and other tropical products. Altogether the oasal flora has considerable variety ”