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Abyssinia

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ABYSSINIA (officially Ethiopia), an inland country and empire of North-east Africa lying, chiefly, between 5° and 15° N. and 35° and E. It is bounded on the north by Eritrea (Italian), on the west by the Anglo-Egyptian Sudan, on the south-west and south by Uganda and Kenya, on the south-east and east by British, Italian and French Somaliland. The coast lands in European hands, which cut off Abyssinia from access to the sea, vary in width from 4o to 250 miles and are narrowest on the north-east border near the Red Sea. Abyssinia in the north is 23orn. east to west, but is 9oom. wide along latitude 9° N., and resembles a triangle with apex north. It is divided into Abyssinia proper (i.e., the old Ethiopian empire consisting of Tigre, Amhara, Gojam and part of Shoa) with the south west Galla highlands and the remainder of Shoa all forming a geographical unit—and cut off from it by the great Rift valley— and the Somaliland plateau with Harar: nearly all this country being surrounded by tracts of low-lying desert. The area of the whole State is about 35o,000sq.m., of which Abyssinian Somaliland covers about a third. Pop. estimated at about 5,500,00o.

Physical Features

Between the Upper Nile and the low south-west shores of the Red Sea and the Gulf of Aden lie elevated plateaux with mountain ranges. The plateaux rise abruptly from the plains, constituting outer mountain chains. The Abyssinian highlands are thus a clearly marked orographic division. From Ras Kasar (18°N.) to Annesley Bay (15°N.) the eastern wall of the plateau runs paral lel to the Red Sea. It then turns due south and follows closely the line of 40°E. for some 400m. About 9°N. the River Hawash flows east through the opening of the Rift valley. The main range at this point trends south-west, while south of the Hawash valley, which is some 3,000ft. below the level of the mountains, another massif rises in a direct line south. The second range sends a chain (the Harar Hills) east to the Gulf of Aden. The two chief eastern ranges run parallel south by west on either side of the Rift valley—in which are a series of lakes—to about 3°N., the outer (eastern) spurs of the plateau still keeping along the line of 4o°E. The southern escarpment of the plateau is highly ir regular, but has a general direction north-west and south-east from 6°N. to 3°N. The western wall of the plateau, from 6°N. to I ON., is precipitous. North of 11°N. the hills turn more to the east, and fall more gradually to the plains at their base. On its northern face also the plateau falls in terraces to the level of the eastern Sudan. The eastern escarpment has a mean height of 7,00o to 8,000ft., and is often precipitous. Torrents descend narrow deep clefts to lose themselves in the sandy coast land; they afford means of reaching the plateau, as alternatives to the easier route through the Hawash valley. On surmounting this rocky barrier the traveller finds that the encircling rampart rises little above the normal level of the plateau. The northern high lands, mainly io° to 15°N., consist of Archaean rocks of mean height 7,00o to 7,5ooft., and a deep central depression contains Lake Tana. Above the plateau mountain ranges rise to 12,000 and over i5,000ft., with fantastic forms, and cut by enormous fissures due to erosion; some are wider, others have the opposite walls but 200 or 3ooyd. apart, and fall almost vertically thou sands of feet. Numerous isolated flat-topped hills or small plateaus known as ambas, are left. The highest peaks are in the Simen (or Semien) ranges, north-east of Lake Tana, which culminate in a snow-covered peak, Dajan (15,16oft.). Parallel with the eastern escarpment the heights rise to Mt. Kollo (14,Iooft.) south-west of Magdala. The valley between these hills and the eastern escarpment is one of the largest and most profound chasms in Abyssinia. Between Lake Tana and the eastern hills are Mounts Guna (13,800ft.) and Uara Sahia (13,000ft.). The highlands south of latitude io°N. have more open tableland than the northern portion and fewer lofty peaks, but the general character is still that of a much broken hilly plateau.

The uplands usually slope north-west and nearly all the large rivers flow to the Nile ; the Takkaze in the north, the Abbai in the centre, and the Sobat in the south make up four-fifths of the entire drainage. The rest is carried off almost due north by the Khor Baraka, which occasionally reaches the Red Sea south of Suakin, by the Hawash, which runs out in the salt lake area near the head of Tajura Bay; by the Webi Shibeli and Juba, which flow south-east through Somaliland, though the Shibeli fails to reach the Indian ocean ; and by the Omo, the main feeder of the closed basin of Lake Rudolf. The Takkaze, the true upper course of the Atbara, falls from about 7,000ft. in the central tableland to 2,5ooft. in the tremendous crevasse through which it sweeps west, north, and west again, to the western terraces and the Sudan. During the rains the Takkaze (i.e., the "Terrible") rises some i8ft. above its normal level, and at this time forms an impassable barrier between the northern and central provinces. Lower down, the river has the Arab name Setit. The Setit is joined (i4° io'N., 36°E.) by the Atbara, formed by several streams of the mountains west and north-west of Lake Tana. The Gash or Mareb is the most northerly Abyssinian river flowing towards the Nile. It rises on the landward side of the eastern escarpment within 5o miles of Annesley Bay on the Red Sea, and reaches the Sudan near Kassala to lose itself in the sandy plain. The Mareb is dry for a great part of the year, but like the Takkaze has sudden freshets during rains. Only the left bank of the upper course of the river is in Abyssinian territory, the Mareb here forming the boundary between Eritrea and Abyssinia.

The Abbai or Blue Nile has its source near Mt. Denguiza in the Gojam highlands (about I ON. and 37°E.) and first flows for 7om. nearly due north to the south side of Lake Tana (q.v.), through which it runs for some 20 miles and, escaping by a deep crevasse, bends in a great semicircle, east, south and north-west, the reverse of that of the Takkaze, down to the plains of Sennar. The Abbai has many perennial tributaries, of which the principal are the Bashilo, the Jamma, the Muger, the Gudiv, the Didessa, largest of all, and the Yabus. The right-hand tributaries, rising mostly on the western sides of the plateau, have steep slopes and are generally torrential; the Bolassa is perennial, and the Rahad and the Dinder are important in flood-time.

In the mountains and plateaux of Kaffa and Galla in south-west Abyssinia rise the chief affluents of the Sobat tributary of the Nile. The Akobo joins the Pibor, which unites with the Baro to form the Sobat. These rivers (which form for 25om. the west or south-west frontiers of Abyssinia) descend in great falls, and like other Abyssinian streams are unnavigable in their upper courses. The Baro on reaching the plain affords, however, an open water way to the Nile (see NILE, SOGAT, and SUDAN).

The chief eastward river is the Hawash, rising in the Shoan uplands and bending first south-east and then north-east. It reaches the Afar (Danakil) lowlands through a broad breach in the eastern escarpment of the plateau, where it is nearly goof t. wide and 4f t. deep, even in the dry season, and during the floods rises 50 or 6oft. above low-water mark, thus inundating the plains for many miles along both its banks. Yet it fails to reach the coast and after a winding course of about 5oom. is lost near Lake Aussa, some 6o or 7om. from the head of Tajura Bay. From Shoa south-west to Lake Rudolf extends a chain of lovely upland lakes, some fresh, some brackish, some completely closed, others connected by short channels, the chief links in their order from north to south being:— Zwai, communicating southwards with Hora Abyata, which connects with Langana, all in the Arusi Galla territory; then Shala and Awusa; farther south Abaya (Margherita) with an outlet to a smaller tarn, Chamo, in the romantic Baroda and Gamo districts, skirted on the west by grassy slopes and wooded ranges (6,000 to nearly 9,000ft.); lastly, in the Asille country, Lake Stefanie, the Chuwaha of the natives, completely closed and about i,800ft. above sea. To the same system obviously belongs the neighbouring Lake Rudolf (q.v.), larger than all the rest together. This lake receives at its northern end (r,800ft. above sea level) the waters of the Omo, a rapid and unnavigable perennial stream with many affluents, rising in the Shoa highlands and falling 6,000ft. in its course of 37om. The chief rivers of Somaliland (q.v.), Webi Shibeli and Juba (q.v.), rise on the south-eastern slopes of the Abyssinian escarpment and most of their course is through Abyssinian territory.

Geology The East African tableland is continued into Abyssinia, the following formations being represented : Archaean.—Metamorphic rocks, the main mass of the table land, are exposed in every deep valley in Tigre and along the Blue Nile. Mica schists are most prevalent. Hornblende schists also occur and a compact felspathic rock in the Suris defile. The foliae of the schists strike north and south.

Triassic ( ?).

In the region of Adigrat the metamorphic rocks are invariably overlain by white and brown sandstones, unfossiliferous, and attaining a maximum thickness of i,000ft. They are overlain by the fossiliferous limestones of the Antalo group. Around Chilga and Adigrat coal-bearing beds occur, which Blanford suggests may be of the same age as the coal-bearing strata of India. The Adigrat sandstone possibly represents some portion of the Karoo formation of South Africa.

Jurassic.

The fossiliferous limestones of Antalo are generally horizontal, but much disturbed when interstratified with trap rocks. The fossils are all characteristic Oolite forms and include a species of Hemicidaris, Pholadomya, Ceromya, Trigonia and Alaria.

Igneous Rocks.

Above a height of 8,000ft. the country con sists of bedded traps belonging to two distinct and unconformable groups. The lower (Ashangi group) consists of basalts and dolerites often amygdaloidal. Their relation to the Antalo lime stones is uncertain, but Blanford considers them to be not later in age than the Oolite. The upper (Magdala group) contains much thick trachytic rock lying perfectly horizontally, and giv ing rise to a series of terraced ridges characteristic of central Abyssinia. They are interbedded with unfossiliferous sandstones and shales. Of more recent date (probably Tertiary) are some igneous rocks, rich in alkalis, in parts of southern Abyssinia. Still more recent are the basalts and ashes west of Massawa and around Annesley Bay, and known as the Aden volcanic series. The older igneous rocks have suffered severe denudation, giving deep and narrow ravines, sometimes to a depth of 3,00o to 4,000f t.

Climate.

Somaliland and the Danakil lowlands are hot and dry with semi-desert conditions ; the lower basin of the Sobat is hot, swampy and malarious. But over most of Abyssinia, as well as the Galla highlands, the climate is very healthy and temperate. The country lies wholly within the tropics, but its nearness to the equator is counterbalanced by the elevation of the land. In the deep valley of the Takazze and Abbai, and generally below 4,000ft., conditions are torrid and fevers preva lent. On the uplands, however, the air is bracing and the nights very bleak. The mean range of temperature is between 6o° and 8o°. On the higher mountains the climate is Alpine. The atmos phere on the plateaus is exceedingly clear. In addition to varia tion in climate with elevation, the year may be divided into two main seasons, the dry (baga) from Oct. to mid-June, and the rainy (karamt), caused by the south-west monsoon, from mid June to the end of September. There is also a period of so-called "little rains," generally about March.

The incidence of the rains varies slightly in different parts of the country, the rain moving from north to south; the average annual rainfall at Addis Ababa over a period of 25 years amounted to I,200MM. ; it is on the whole rather lighter in the north. The rainy season is of great importance not only to Abyssinia but to the countries of the Nile valley, as the pros perity of the eastern Sudan and Egypt is largely dependent upon the Abyssinian rainfall.

Flora and Fauna.

As in a day's journey the traveller may pass from torrid to almost Alpine conditions of climate, so great also is the range of flora and fauna. In the valleys and lowlands vegetation is dense, but the plateaux are comparatively bare, with thinly scattered trees and bushes. The glens and ravines are often thickly wooded, and offer a delightful contrast to the open downs. These conditions are particularly characteristic in the north; in the south the upland vegetation is more luxuriant. The date palm, mimosa, wild olive, giant sycamores, junipers and laurels, the myrrh and other gum trees (gnarled and stunted, these flourish most on the eastern foothills), a magnificent pine (the Natal yellow pine, which resists the attacks of the white ant), the fig, orange, lime, pomegranate, peach, apricot, banana and other fruit trees; the grape vine (rare), blackberry and rasp berry; the cotton and indigo plants, and occasionally the sugar cane, are all found. There are in the south large forests of valuable timber ; and the coffee plant is indigenous in the Kaffa country, whence it takes its name. Many grasses and flowers abound. Large areas in the highlands are covered by the Kosso tree, which grows from 3o to 4oft. high and has abundant pend ant red blossoms ; the flowers and the leaves are prized for medic inal purposes. The fruit of the kurarina, found almost exclu sively in Shoa, yields a black grain highly esteemed as a spice. On the tableland a great variety of grains and vegetables are culti vated. A fibrous plant, the sanseviera, grows wild in the semi desert regions of the north and south-east.

Elephant and rhinoceros are found in low-lying districts, especially in the Sobat valley. The hippopotamus and crocodile inhabit many of the rivers and lakes, in some of which otters of large size are plentiful. Lions abound in the low countries and in Somaliland. Leopards, spotted and black, are numerous and often large ; hyaenas are found everywhere and are hardy and fierce; lynx, wolf, wild dog and jackal are also common. Boars and badgers are more rarely seen. The giraffe is found in the west; the zebra and wild ass frequent the lower plateaux and the rocky hills of the north. Antelopes and gazelles of many varieties are numerous in most parts and include greater and lesser kudu (both rather rare), onyx, duiker, gemsbuck, hartebeest, gerenuk (the most common---it has long thin legs and a camel-like neck), klip-springer, found on the high plateaus as well as in the lower districts, and the dik-dik, the smallest of the antelopes, rarely over 10 lb., common in the low countries and the foothills. The rarest of all these is the nyala. The civet is found in many parts but chiefly in the Galla regions. Squirrels and hares, monkeys, notably the guereza, gelada, guenon and dog-faced baboon, range abundantly from the warm lowlands to heights of i o,000ft. Eagles, vultures, hawks, bustards and other birds of prey, par tridges, duck, teal, guinea-fowl, sand-grouse, curlews, woodcock, snipe, pigeons, thrushes and swallows are very plentiful. A fine variety of ostrich is common. Among birds prized for plumage are the marabout, crane, heron, blackbird, parrot, jay, and many sun-birds of extraordinary brilliance. Serpents are not numerous but several are poisonous. The bee's honey is an important part of the people's food. The locust is a pest. There are thousands of varieties of butterflies and other insects.

south, north, plateau, eastern and lake