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Revision 4 . . September 10, 2001 1:08 pm by Alan Millar [Text from 1911 encyclopedia - please edit as needed. ]
Revision 3 . . September 9, 2001 12:36 am by Koyaanis Qatsi
  

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Ethiopia is located in the Horn of Africa and is bordered on the north and northeast by Eritrea, on the east by Djibouti and Somalia, on the south by Kenya, and on the west and southwest by Sudan. The country has a high central plateau that varies from 1,800 to 3,000 meters (6,000-10,000 ft.) above sea level, with some mountains reaching 4,620 meters (15,158 ft.). Elevation is generally highest just before the point of descent to the Great Rift Valley, which splits the plateau diagonally. A number of rivers cross the plateau--notably the Blue Nile rising from Lake Tana. The plateau gradually slopes to the lowlands of the Sudan on the west and the Somali-inhabited plains to the southeast.
Ethiopia is located in the Horn of Africa and is bordered on the north and northeast by Eritrea, on the east by Djibouti and Somalia, on the south by Kenya, and on the west and southwest by Sudan. The country has a high central plateau that varies from 1,800 to 3,000 meters (6,000-10,000 ft.) above sea level, with some mountains reaching 4,620 meters (15,158 ft.). Elevation is generally highest just before the point of descent to the Great Rift Valley, which splits the plateau diagonally. A number of rivers cross the plateau--notably the Blue Nile rising from Lake Tana. The plateau gradually slopes to the lowlands of the Sudan on the west and the Somali-inhabited plains to the southeast.

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Text from 1911 encyclopedia - please edit as needed.


(1) Physical Features.-- Between the valley of the Upper Nile
and the low lands which skirt the south-western shores of the
Red Sea and the Gulf of Aden is a region of elevated plateaus
from which rise various mountain ranges. These tablelands
and mountains constitute Ethiopia, Shoa, Kaffa and Galla
land. On nearly every side the walls of the plateaus rise
with considerable abruptness from the plains, constituting
outer mountain chains. The Ethiopian highlands are thus
a clearly marked orographic division. From Ras Kasar (18 deg.
N.) to Annesley Bay (15 deg. N.) the eastern wall of the plateau
runs parallel to the Red Sea. It then turns due S. and follows
closely the line of 40 deg. E. for some 400 miles About 9 deg. N. there
is a break in the wall, through which the river. Hawash flows
eastward. The main range at this point trends S.W., while
south of the Hawash valley, which is some 3000 ft. below the
level of the mountains, another massif rises in a direct line
south. This second range sends a chain (the Harrar hills)
eastward to the Gulf of Aden. The two chief eastern ranges
maintain a parallel course S. by W., with a broad upland
valley between---in which valley are a series of lakes---to
about 3 deg. N., the outer (eastern) spurs of the plateau still
keeping along the line of 40 deg. E. The southern escarpment of
the plateau is highly irregular, but has a general direction
N.W. and S.E. from 6 deg. N. to 3 deg. N. It overlooks the depression
in which is Lake Rudolf and---east of that lake--southern
Somaliland. The western wall of the plateau from 6 deg. N.
to 11 deg. N. is well marked and precipitous. North of 11 deg.
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 is the best defined of these
outer ranges. It has a mean height of from 7000 to 8000
ft., and in many places rises almost perpendicularly from the
plain. Narrow and deep clefts, through which descend mountain
torrents to lose themselves in the sandy soil of the coast
land, afford means of reaching the plateau, or the easier
route through the Hawash valley may be chosen. On surmounting
this rocky barrier the traveller finds that the encircling
rampart rises little above the normal level of the plateau.

(2) The aspect of the highlands is most impressive. The
northern portion, lying mainly between 10 deg. and 15 deg. N.,
consists of a huge mass of Archaean rocks with a mean height
of from 7000 to 7500 ft. above the sea, and is fl00ded in a
deep central depression by the waters of Lake Tsana. Above
the plateau rise several irregular and generally ill-defined
mountain ranges which attain altitudes of from 12,000 to over
15,000 ft. Many of the mountains are of weird and fantastic
shape. Characteristic of the country are the enormous
fissures which divide it, formed in the course of ages by
the erosive action of water. They are in fact the valleys
of the rivers which, rising on the uplands or mountain
sides, have cut their way to the surrounding lowlands. Some
of the valleys are of considerable width; in other cases the
opposite walls of the gorges are but two or three hundred
yards apart, and fall almost vertically thousands of feet,
representing an erosion of hard rock of many millions of cubic
feet. One result of the action of the water has been the
formation of numerous isolated flat-topped hills or small
plateaus, known as ambas, with nearly perpendicular sides.
The highest peaks are found in the Simen (or Semien) and Gojam
ranges. The Simen Mountains he N.E. of Lake Tsana and
culminate in the snow-covered peak of Daschan (Dajan), which
has an altitude of 15,160 ft. A few miles east and north
respectively of Dajan are Mounts Biuat and Abba Jared, whose
summits are a few feet only below that of Dajan. In the Chok
Mountains in Gojam Agsias Fatra attains a height of 13,600 ft.

Parallel with the eastern escarpment are the heights of Baila
(12,500 ft.), Abuna Josef (13,780 ft.), and Kollo (14,100
ft.), the last-named being S.W. of Magdala. The valley
between these hills and the eastern escarpment is one of
the longest and most profound chasms in Ethiopia. Between
Lake Tsana and the eastern hills are Mounts Guna (13,800
ft.) and Uara Sahia (13,000 ft.). The figures given are,
however, approximate only. The southern portion of the
highlands---the 10 deg. N. roughly marks the division between
north and south---has more open tableland than the northern
portion and fewer lofty peaks. Though there are a few heights
between 10,000 and 12,000 ft., the majority do not exceed 8000
ft. But the general character of the southern regions is
the same as in the north---a much-broken hilly plateau.

Most of the Ethiopian uplands have a decided slope to the
north-west, so that nearly all the large rivers find their way
in that direction to the Nile. Such are the Takazze in the
north, the Abai in the centre, and the Sobat in the south, and
through these three arteries is discharged about 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
saline lacustrine district near the head of Taiura Bay; by the
Webi Shebeli (Wabi Shebeyli) and Juba, which flow S.E. through
Somaliland, though the Shebeli fails to reach the Indian Ocean;
and by the Omo. the main feeder of the closed basin of Lake Rudolf.

The Takazze, which is the true upper course of the Atbara,
has its head-waters in the central tableland; and falls from
about 7000 to 2500 ft. in the tremendous crevasse through
which it sweeps round west, north and west again down to the
western terraces, where it passes from Ethiopian to Sudan
territory. During the rains the Takazze (i.e. the
"Terrible") rises some 18 ft. above its normal level, and
at this time forms an impassable barrier between the northern
and central provinces. In its lower course the river is
known by the Arab name Setit. The Setit is joined (14 deg. 10'
N., 36 deg. E.) by the Atbara, a river formed by several streams
which rise in the mountains W. and N.W. of Lake Tsana.
The Gash or Mareb is the most northerly of the Ethiopian
rivers which flow towards the Nile valley. Its head-waters
rise on the landward side of the eastern escarpment within
50 miles of Annesley Bay on the Red Sea. It reaches the
Sudan plains near Kassala, beyond which place its waters are
dissipated in the sandy soil. The Mareb is dry for a great
part of the year, but like the Takazze is subject to sudden
freshets during the rains. Only the left bank of the upper
course of the river is in Ethiopian territory, the Mareb
here forming the boundary between Eritrea and Ethiopia.

(3) The Abai---that is, the upper course of the Blue Nile--has
its source near Mount Denguiza in the Goiam highlands (about
11 deg. N. and 37 deg. E.), and first flows for 70 miles nearly due
north to the south side of Lake Tsana. Tsana (q.v.), which
stands from 2500 to 3000 ft. below the normal level of the
plateau, has somewhat the aspect of a flooded crater. It has
an area of about 1100 sq. m., and a depth in some parts of 250
ft. At the south-east corner the rim of the crater is, as
it were. breached by a deep crevasse through which the Abai
escapes, and here dovelb. ps a great semicircular bend like that
of the Takazzo, but in the reverse direction---east, south
and north-west---down to the plains of Sennar, where it takes
the name of Bahr-el-Azrak or Blue Nile. The Abai has many
tributaries. Of these the Bashilo rises near Magdala and
drains eastern Amhara; the Jamma rises near Ankober and drains
northern Shoa; the Muger rises near Adis Ababa and drains
south-western Shoa; the Didessa, the largest of the Abai's
affluents, rises in the Kaffa hills and has a generally S. to
N. course; the Yabus runs near the western edge of the plateau
escarpment. All these are perennial rivers. The right-hand
tributaries, rising mostly on the western sides of the
plateau, have steep slopes and are generally torrential in
character. The Bolassa, however, is perennial, and the
Rahad and Dinder are important rivers in flood-time.

In the mountains and plateaus of Kaffa and Galla in the
south-west of Ethiopia rise the Baro, Gelo, Akobo and
other of the chief affluents of the Sobat tributary of the
Nile. The Akobo, in about 7 deg. 50' N. and 33 deg. E., joins the
Pibor, which in about 8 1/2 deg. N. and 33 deg. 20' E. unites with
the Baro, the river below the confluence taking the name of
Sobat. These rivers descend from the mountains in great
falls, and like the other Ethiopian streams are unnavigable in
their upper courses. The Baro on reaching the plain becomes,
however, a navigable stream affording an open waterway to the
Nile. The Baro, Pibor and Akobo form for 250 miles the W. and
S.W. frontiers of Ethiopia (see NILE, SOBAT and SUDAN.)

The chief river of Ethiopia flowing east is the Hawash
(Awash, Awasi), which rises in the Shoan uplands and makes
a semicircular bend first S.E. and then N.E. It reaches the
Afar (Danakil) lowlands through a broad breach in the eastern
escarpment of the plateau, beyond which it is joined on its
left bank by its chief affluent, the Germama (Kasam), and
then trends round in the direction of Tajura Bay. Here the
Hawash is a copious stream nearly 200 ft. wide and 4 ft.
deep, even in the dry season, and during the floods rising
50 or 60 ft. 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 500 miles
passes (in its lower reaches) through a series of badds
(lagoons) to Lake Aussa, some 60 or 70 miles from the head.of
Tajura Bay. In this lake the river is lost. This remarkable
phenomenon is explained by the position of Aussa in the
centre of a saline lacustrine depression several hundred
feet below sea-level. While most of the other lagoons are
highly saline, with thick incrustations of salt round their
margins, Aussa remains fresh throughout the year, owing to
the great body of water discharged into it by the Hawash.

Another lacustrine region extends from the Shoa heights
south-west to the Samburu (Lake Rudolf) depression.
In this 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
are:---Zwai, communicating southwards with Hara and Lamina,
all in the Arusi Galla territory; then Abai with an outlet
to a smaller tarn in the romantic Baroda and Gamo districts,
skirted on the west sides by grassy slopes and wooded ranges
from 6000 to nearly 9000 ft. high; lastly, in the Asille
country, Lake Stefanie, the Chuwaha of the natives, completely
closed and falling to a level of about 1800 ft. above the
sea. To the same system obviously belongs the neighbouring
Lake Rudolf (q.v.), which is larger than all the rest put
together. This lake receives at its northern end the waters
of the ()mo, which rises in the Shoa highlands and is a
perennial river with many affluents. In its course of some
370 miles it has a total fall of about 6000 ft. (from 7600
at its source to 1600 at lake-level), and is consequently
a very rapid stream, being broken by the Kokobi and other
falls, and navigable only for a short distance above its
mouth. The chief rivers of Somaliland (q.v.), the Webi
Shebeli and the Juba (q.v.), have their rise on the
south-eastenn slopes of the Ethiopian escarpment, and the
greater part of their course is through territory belonging to
Ethiopia. There are numerous hot springs in Ethiopia, and
earthquakes, though of no great severity, are not uncommon.

(4) Geology.
The East African tableland is continued
into Ethiopia. Since the visit of W. T. Blanford in
1870 the geology has received little attention from
travellers. The following formations are represented:--



Sedimentary and Metamorphic.
Recent. Coral, alluvium, sand.
Tertiary. (?) Limestones of Harrar.
Jurassic. Antalo Limestones.
Triassic (?). Adigrat Sandstones.
Archaean. Gneisses, schists, slaty rocks.

Igneous.
Recent. Aden Volcanic Series.
Tertiary, Cretaceous (?). Magdala group.
Jurassic. Ashangi group.


Archaean.--The metamorphic rocks compose the main mass
of the tableland, and are exposed in every deep valley
in Tigre and along the valley of the Blue Nile. Mica
schists form the prevalent rocks. Hornblende schist
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 1000
feet. They are overlain by the fossiliferous limestones of
the Antalo group. Around Chelga 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 Karroo formation of South Africa.

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

Igneous Rocks.---Above a height of 8000 ft. the country consists
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
limestones is uncertain, but Blanford considers them to be
not later in age than the Oolite. The upper (Magdala group)
contains much trachytic rock of considerable thickness,
lying perfectly horizontally, and giving rise to a series of
terraced ridges characteristic of central Ethiopia. They are
interbedded with unfossiliferous sandstones and shales. Of
more recent date (probably Tertiary) are some igneous rocks,
rich in alkalis, occurring in certain localities in southern
Ethiopia. Of still more recent date are the basalts and
ashes west of Massawa and around Annesley Bay and known as
the Aden Volcanic Series. With regard to the older igneous
rocks, the enormous amount they have suffered from denudation
is a prominent feature. They have been worn into deep and
narrow ravines, sometimes to a depth of 3000 to 4000 ft.

(5) Climate.---The climate of Ethiopia and its dependent
territories varies greatly. Somaliland and the Danakil lowlands
have a hot, dry climate producing semi-desert conditions; the
country in the lower basin of the Sobat is hot, swampy and
malarious. But over the greater part of Ethiopia 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 valleys of the Takazze and Abai,
and generally in places below 4000 ft., the conditions are
tropical and fevers are prevalent. On the uplands, however,
the air is cool and bracing in summer, and in winter very
bleak. The mean range of temperature is between 60 deg. and
80 deg. F. On the higher mountains the climate is Alpine in
character. The atmosphere on the plateaus is exceedingly
clear, so that objects are easily recognizable at great
distances. In addition to the variation in climate dependent
on elevation, the year may be divided into three seasons.
Winter, or the cold season, lasts from October to February,
and is followed by a dry hot period, which about the middle of
June gives place to the rainy season. The rain is heaviest in
the Takazze basin in July and August. In the more southern
districts of Gojam and Wallega heavy rains continue till
the middle of September, and occasionally October is a wet
month. There are also spring and winter rains; indeed rain
often falls in every month of the year. But the rainy season
proper, caused by the south-west monsoon, lasts from June to
mid-September, and commencing in the north moves southward.
In the region of the Sobat sources the rains begin earlier
and last longer. The rainfall varies from about 30 in. a
year in Tigre and Amhara to over 40 in. in parts of Galla
land. The rainy season is of great importance not only to
Ethiopia but to the countries of the Nile valley, as the
prosperity of the eastern Sudan and Egypt is largely dependent
upon the rainfall. A season of light rain may be sufficient
for the needs of Ethiopia, but there is little surplus water
to find its way to the Nile; and a shortness of rain means
a low Nile, as practically all the flood water of that river
is derived from the Ethiopian tributaries (see NILE.)

(6) Flora and Fauna.--As in a day's journey the traveller
may pass from tropical to almost Alpine conditions of
climate, so great also is the range of the flora and fauna.
In the valleys and lowlands the vegetation is dense, but
the general appearance of the plateaus is of a comparatively
bare country with trees and bushes thinly scattered over
it. The glens and ravines on the hillside are often thickly
wooded, and offer a delightful contrast to the open downs.
These conditions are particularly characteristic of the northern
regions; in the south the vegetation on the uplands is more
luxuriant. Among the many varieties of trees and plants
found are 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 raspberry; the cotton and indigo
Plants, and occasionally the sugar cane. There are in the
south large forests of valuable timber trees; and the coffee
plant is indigenous in the Kaffa country, whence it takes its
name. Many kinds of grasses and flowers abound. Large areas
are covered by the kussa, a hardy member of the rose family,
which grows from 8 to 10 ft. high and has abundant pendent red
blossoms. The flowers and the leaves of this plant are
highly prized for medicinal purposes. The fruit of the
hurarina, a tree found almost exclusively in Shoa, yields
a black grain highly esteemed as a spice. On the tableland
a great variety of grains and vegetables are cultivated.
A fibrous plant, known as the sanseviera, grows in a wild
state in the semi-desert regions of the north and south-east.

In addition to the domestic animals enumerated below (sec. 8) the
fauna is very varied. Elephant and rhinoceros? are numerous in
certain low-lying districts, especially in the Sobat valley.
The Ethiopian rhinoceros has two horns and its skin has no
folds. The hippopotamus? and crocodile? inhabit the larger
rivers flowing west, but are not found in the Hawash, in which,
however, otter?s of large size are plentiful. Lion?s abound
in the low countries and in Somaliland. In central Ethiopia
the lion is no longer found except occasionally in the river
valleys. Leopard?s, both spotted and black, are numerous and
often of great size; hyenas are found everywhere and are
hardy and fierce; the lynx, wolf, wild dog and jackal are also
common. Boar?s and badger?s are more rarely seen. The giraffe
is found in the western districts, the zebra and wild ass
frequent the lower plateaus and the rocky hills of the
north. There are large herds of buffalo and antelope?, and
gazelle?s of many varieties and in great numbers are met
with in most parts of the country. Among the varieties are
the greater and lesser kudu? (both rather rare); the duiker?,
gemsbuck?, hartebeest, gerenuk (the most common--it has
long thin legs and a camel-like neck); klipspringer, found
on the high plateaus as well as in the lower districts;
and the dik-dik, the smallest of the antelopes, its weight
rarely exceeding 10 lb. , common in the low countries and the
foothills. The civet? is found in many parts of Ethiopia,
but chiefly in the Galla regions. Squirrels and hare?s
are numerous, as are several kinds of monkey?s, notably
the guereza, gelada, guenon and dog-faced baboon?. They
range from the tropical lowlands to heights of 10,000 ft.

Birds are very numerous, and many of them remarkable for the
beauty of their plumage. Great numbers of eagle?s, vultures, hawk?s,
bustards and other birds of prey are met with; and partridge?s,
duck?, teal, guinea-fowl, sand-grouse, curlews, woodcock, snipe,
pigeon?s, thrushes and swallows are very plentiful. A fine
variety of ostrich is commonly found. Among the birds prized
for their plumage are the marabout, crane?, heron?, blacks bird,
parrot?, jay and humming-birds of extraordinary brilliance,

Among insects the most numerous and useful is the bee, honey
everywhere constituting an important part of the food of the
inhabitants. Of an opposite class is the locust?.
There are thousands of varieties of
butterflies? and other insects.
Snake?s are not numerous, but several species are poisonous.

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