98 • NORTH-WEST AFRICA. Spartal, was far too long for its slight breadth, and thus became broken into several fragments, analogous to those which destroyed the unity of Italy. But the form and outlines of countries have a continually decreasing influence on the destiny of their inhabitants, the work of man tending more and more to reduce the importance of distances and diminish the contrasts of climate and relief. Tunis is at present more intimately associated with Tangiers in the extreme west than it formerly was with the adjacent districts of Bon and Cabes, separated from Goletta Bay by stormy headlands. In their hydrographic systems Tunisia, Algeria, and Marocco present analogous conditions. The northern slope of the Atlas, facing the Atlantic and Mediterranean, is too narrow to develop large fluvial basins. Hence only a small number of watercourses, rising on the upland steppes, or at least fed by affluents from those reo-ions, have succeeded in forcing their way through the border ranges seaward, thus presenting a development analogous to that of the European rivers falling into the ^Icditerranean. Thus the Maluya of Marocco, the Algerian Shelif, and the Mojerdu of Tunis, are exceeded in length only by the llhone and Ebro. On the Sahara slope there would certainly be no lack of space for the running waters to excavate long channels in the direction of the Niger, the Atlantic, or the Syrtes. But here the rainfall fails, and the streams have no volume corresponding to the extent of their basins. Except the Draa, which rises on the southern slope of the Marocco Atlas, but fails to reach the Atlantic opposite the Canary Islands, there is not a single f«tream in the Sahara region which flows freely on the surface from its source to the sea. The beds formerly excavated, when the rainfall was more abundant, may, however, still be traced in spite of the shifting dunes, and it is evident enough that they formed water systems rivalling in extent that of the Euphrates. One of these old streams, rising in the Atlas, flowed southwards to the Niger ; another, the mighty Igharghar with its vast system of affluents, formed in the Jebel Ahaggar and Jebel Tasili, took a northerly course to the depression of the Algerian shotts ; but within the present geological period it has had no outlet to the Gulf of Cabes. Its area of drainage, probably exceeding 320,000 square miles, is scarcely inferior to that of the Danube. Ethnical Elements. Owing to the substantial uniformity of the physical, hydrographic, and climatic conditions throughout Mauritania, the local flora and fauna must also everywhere betray a certain resemblance, although in many places the migrations have beeii checked by natural obstructions, thus giving rise to many gradual modifications of species. Between Capes Bon and Nun are met representatives of the same races of mankind, differing in their distribution according to the endless variety of the environment and the chequered course of events. Everywhere in Mauritania the Berber element, of unknown origin, constitutes the fundamental stock, and, accord- ing to Faidherbe still comprises at least three-quarters of the present population, estimated at about ten millions between the sea and the desert. But although
