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12
ABYSSINIA
[geography


the Anglo-Egyptian Sudan, with the meridian of 35° E. be tween the river Rahad, and 4' N. lat., and on the south with this parallel eastwards to 40° E. Here the line is deflected irregularly south-eastwards to Logh, on the river Juba, and then runs north by east at about 180 miles from the coast along the Italian frontier as far as British Somali- land. Beyond this district the boundary 18 coterminous eastwards with French Somaliland as defined in 1897, and the Italian colony of Eritrea as far north as 15° N. is certainly over 15,000 feet, and was long supposed to be the lat., and westwards to the Atbara, whence the line runs loftiest summit in Africa north of Kenia. But it now appears to south and west to the point where the river Rahad is intersected by the meridian of 35° E. Within these limits the reconstituted Abyssinian empire has a total area of about 320,000 square miles, with a population approxi- mately estimated at 9,000,000 distributed as under :-

Area in Sq. Miles. Population.
Hamran, Beni-Amer, Bilin, Marea, Mensa, Basé(Kunama), and Barea districts between the Plateau and Upper Nubia 30,000 150,000
Abyssinia proper (North Ethiopia): the old kingdoms of Tigré, Lasta, Amhara and Gojam 80,000 2,600,000
Shoa (Menelek's patrimony) 20,000 1,000,000
Harrar and neighbouring districts 10,000 250,000
Ogaden and other parts of Somalia 100,000 1,000,000
South Ethiopia (Gallaland) 80,000 4,000,000
—— ——
Total (1901) 320,000 9,000,000
—— ——

Despite its enlarged domain, Abyssinia still remains an inland state, nowhere reaching the coast, where all its natural outlets — Massawa and Assab on the Red Sea,

Jibuti, Zeila, Bulhar, and Berbera on the Gulf of Aden- are held by foreign Powers. Even on the west side it is cut off from direct access to the White Nile, where both banks of the river are included in the Anglo-Egyptian Sudan.

No doubt the upper courses of the eastern affluents of the main stream, Sobat, Abai (Blue Nile), Takazzé (Atbara, or Black Nile), flow through Abyssinian territory. But here they have the character of intermittent wadies, nearly dry for a great part of the year, and during the rains raging torrents rushing wildly through deep rocky gorges down to the lowlands, hence at no time navigable, and of Rivers and little use even for irrigation purposes. Hence their ex- clusion from marine and fluvial navigable waters has been discharged about four-fifths of the entire drainage. The rest is carried off by the Khor Baraka, which oceasionally reaches the all the more acutely felt by the native rulers, whose foreign policy continues to be largely directed towards acquiring territory both on the seaboard and along the right bank of the White Nile.

The Ethiopian highlands, of which Abyssinia proper forms the northern, and Gallaland the southern section, occupy most of the Physical space between the lowlands of the White Nile basin features. and those of the Eritrean rift valley, separating them from the Red Sea and the Indian Ocean. Their long axis is disposed in the direction of the meridian, and the whole region broadens out from near the Red Sea at Massa wa southwards to the Lake Rudolf depression. The northern section, lying mainly between 10°-15° N. lat., may be deseribed as a huge mass of Archaean gneiss and sehists, forming a rugged plateau at a mean height of from 7000 to 7500 feet above the sea, profoundly weathered by sub-aerial agencies, and flooded in a deep central depression by the waters of Lake Tsana. Above the plateau, which presents its steepest escarpments towards the rift valley, and falls in terracos northwards and westwards down to the plains of Upper Nubia and Sennar, rise several irregular and generally ill-defined mountain ranges, consisting partly of Jurassic lime- stones and partly of old igneous rocks, great shects of lava and vast piles of volcanic detritus, whieh in the western provinees of Gojam and Simen attain altitudes of from 12,000 to 15,000 or even 16,000 feet. But there appear to be nowhere any active cones, and the very craters have for the most part been obliterated. The plateau formation itself is broken and largely obscured by Vist yawning chasms and fissures, through which the surface or waters escape to the surrounding lowlands. Amid the chaos of Alpine heights and rugged plains which, seen from the higher summits, present the aspect of a storm-tossed sea suddenly solidified, the best - defined mountain system is the coast range, which is formed by the precipitous eastern escarpments of the plateau, and maintains for a distance of about 600 miles a mean elevation of from 7000 to 8000 feet. It thus rises little above the inland plateau, and travellers penetrating from the coast to the interior find that on surmounting this rocky barrier they have already reached the normal level of the whole region. irregular Simen and Gojam groups, the true highlands of North Ethiopia, still rise 6000 or 7000 feet higher, several of their peaks penetrating to the snow-line. Mount Dajan in the Simen range be overtopped by others, such as Abla-yared (15,600 feet), and Buahit (16,000 feet) in the same group. At Ankober (9° N.) the coast range begins to trend round to the south-west, thus assuming the speet of an inland ehain, and gradually increasing in height until it culminates in Mount Meta titel (11,000 feet), and the Entoto range crossed by the Hular Koh Pass (over 12,000 feet) in the kingdom of Shoa. Here the Abyssinian system merges in the South Ethiopian highlands, which are continued at considerable altitudes southwards to the Kafla territory, and then fall rapidly down to the Lake Rudolf depression. Like the northern section, these less-known Galla uplands appear to form much broken hilly plateau, presenting its steepest escarpments on the east side towards Somaliland, and falling more gently in a series of broad terraces down to the lowlands of the Nile basin. Although the routes of the explorers in the Galla and Samburu lands have now been connected by the itineraries of Bottego, Donaldson Smith, Wellby and a few other travellers, no accurate surveys have yet been made, and the heights assigned to the loftier peaks in South Ethiopia (Hamdo, 11,500 feet; Warro, 13,000 feet; Wosho, 16,000 feet) are little more than eonjectural. This region, however, is known to be of a far less rugged eharacter than the Abyssinian tableland, and there are few or no traces of the so-called "ambas," that is, isolated blocks or sections caused by erosion and underground agencies, which are such a characteristic feature of the Shoa and Gojam uplands. Some of the intervening rifts and fissures, which somewhat resemble the Mexican barrancas, are of vast extent and depth, but often very narrow. The most remarkable oecur along the edge of the central plateau," where the total fissure exceeds 6500 feet, measured from the summit of the degas (uplands) down to sea-level. Nowhere else can a more convincing proof be observed of the erosive action of running waters. The two walls of certain gorges, rising nearly vertically within a few feet of each other to a height of some hundreds of feet, represent an erosion of hard rock anounting to at least 10,500 million cubic feet"(Roclus, X. p. 129).

Most of the Abyssinian uplands have a decided north-westerly tilt, so that nearly all the large rivers find their way in this direc- tion inland to the Nile Valley. Such are the Takazné pre in the north, the Abai in the centre, and the Sobati in the south, and through these three arteries is Red Sea below Suakim; the Hawash, which runs out in the saline lacustrine district near the head of Tajura Bay; the Webi- Shebeyli and Juba, which flow through Somaliland to the Indian Ocean; and the Omo, now known to be the main feeder of the elosed basin of Lake Rudolf. The Takazze, which is the tri upper course of the Atbara (the Asiaboras of the ancients, and the Bahr-el-Aswad or "Blaek Nile" of the Arabs), has its source in the Simen uplands, and falls from about 7000 to 2500 feet above sea-level in the tremendous crevasse through which it sweeps round east, north, and west down to the western terraces, where it passes from Abyssinian to Nubian territory. During the rains the Takazzé, ie, the "Terrible," rises some 18 feet above its normal level, and at this time forms an impassable barrier between the northern and central provinees. In the Hamran district, where it becomes the Bahr-Setit, the Takazzé is joined on its left bank by the Upper Atbara, which is formed by the junction of the Angreb, Salaam, Aradeb, Koang, and several other head-streams descending from the Amhara uplands. Below the confluenee the united stream retains the name of Atbara, and farther down receives on its right bank the intermittent waters of the Dareb or Gash, which rises near Adua in Tigré and is dry for a great part of the year, but, like the Tak azzé, is subject to sudden freshets during the rains. From its source to the Nile confluenee at Ed-Damer, where it is now crossed by a railway bridge, the main stream has a total length of about 800 miles, and the drainage area exceeds 20,000 square miles within Abyssinian territory. But the discharge is slight except in the wet season, when it nearly equals that of the Blue Nile. In its lower reaches it rises at times to a height of 30 40 feet, with a breadth of over 600 yards. The Abai-that is, the upper course of the Blue Nile-has its farthest source near Mount Denguiza, in the Gojam highlands, about 11° N. and 55° E., and first