The Highlands of Ethiopia - Part 36
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Part 36

APPENDIX.

Remarks on the Geology, Botany, and Zoology of the Highlands of Southern Abyssinia.

Geology.

When the portion of North-eastern Africa that is to form the province of inquiry received its present configuration, the fountains of the deep may be supposed to have opened at once upon a surface, of which the prior quality and condition has become so shut out from human observation, that a.n.a.logies, drawn from other countries under similar circ.u.mstances, must supply this deficiency.

Porphyry forms the general basis of all the different volcanic formations discernible. From the pinnacle of Jebel Goodah, on the Gulf of Arabia, it may be traced, though indistinctly, in the minor outrunners of the Abyssinian Alps, to the province of Efat, where it pa.s.ses under red sandstone. The princ.i.p.al Shoan range, and the high westerly plateau towards the valley of the Nile, present solely secondary formations, but the porphyry again emerges on the southerly borders in the ranges of Garra Gorphoo and Bulga; whilst the left; bank of the Hawash valley is distinctly of primitive crystalline formation.

The overlying rocks, which seem to have been poured from the centre of this tract, consist of ma.s.ses of trachyte and columnar basalt, of pyramids of wacke, and beds of lava and tufwacke, with strata of conglomerates and sandstones. The former of these, the trachyte and basalt, belong to the lofty mountains of Abyssinia; whereas wacke, lava, tuffo, and scoria, cover the surface, and form the hills of the desert below; and many districts present volcanoes which, not half a century ago, were in violent activity.

The hills of Mentshar, Efat, and Giddem, are detached ranges, running nearly parallel to the Shoan alps. Disclosing in some few spots the nature of their interior, it appears that immediately over the porphyry lies a red sand-stone, embedding vast quant.i.ties of coal, and presenting a true stratification. It consists of minute but quite perfect hexagon dodecaeders of quartz in a white cement, is very soft, and cleaves sometimes in regular squares. Its depth was not observed to be very great, nor did the overlying formations, a marl and conglomerates, seem to form obstacles to the miner.

The Shoan mountains, of alpine height, exhibit a structure of basalt, wacke, and trachyte; the latter, in all its varieties, surrounds a nucleus of basalt, basaltic wacke, and dolerite. The conglomerates and tuffos at their feet, and partly on their terraces and tops, are of trachytic nature, and sometimes pierced through by small dikes of basalt. Veins of ochre and clay, holes filled with scoria, with intrusions of larger or smaller fragments of various rocks and minerals, and a kind of stratification, are the princ.i.p.al features of this trachytic formation.

When the action began, craters or clefts were formed in the then existing crust of trap-rocks, which in their turn were covered with ma.s.ses of trachytic lava; a little later, the tuffos and conglomerates were deposited, which prove the importance of augite in their formation by numerous crystals of pyroxen embedded in them. Subsequently new basaltic eruptions either raised these deposits to their present height, or pierced them through in their original sites, both cases occurring on the same locality.

The basalt composing the hills about Ankober presents no vestige of olivin, nor does it influence the magnetic needle; but a distinction between basalt and greenstone in their finer-grained varieties is difficult; and to determine in words the affinity which they bear to each other in the present instance, the rock might be styled basaltic greenstone. Columns, pentagonal or heptagonal, crown the tops of hills, and seem rather a composition of hornblende than of augite and feldspar.

Scoriaceous varieties are found on the outsides of the later protruded ma.s.ses.

The trachyte is generally a compact ma.s.s of grey feldstein, which contains crystals of gla.s.sy feldspar, irregularly embedded, and in different quant.i.ties. Some varieties are porous, some full of small holes, others black from grains of obsidian; and a few, especially near the dikes, incline to phonolite.

To the westward the ridge terminates in a high plateau, the western Galla provinces of the kingdom. This vast plain is crossed in various directions by hill ranges, the greater part of which do not rise to any considerable height. Here true basalt is disclosed in all the grandeur of its columnar cleavage, but no other species of rock. Deep and narrow ravines carry off the superabundant waters, and pits of tolerable ironstone afford a supply of metal for the manufacture of weapons.

The chief bearing of the mountain chains in Shoa is north and south, with spurs to the west and east. The towering height to which they rise, in a nearly uninterrupted ascent, may be calculated to be from eight to nine thousand feet above the level of the sea, and their single pinnacles far exceed that limit. They are most abrupt, and difficult of access, excepting by the only two pa.s.ses to the high western plateau.

Ravines and chasms of a depth which admits the sun but for few hours, tell of the catastrophe which resulted in their formation. Inaccessible steep cliffs and dismal precipices everywhere line the tiresome footpath of the lonely muleteer.

The hills of Efat present more rounded forms; their slopes are better cultivated, and their tops afford the most eligible positions for the abode of the Abyssinian farmer. During the rainy season, all the many rivers which at other times carry only sufficient water for the purposes of the cultivator, not only fill their deeply-excavated beds, but overflowing and inundating all the lower parts of the hills, would sweep off any of the fragile Abyssinian buildings within reach; but the soil, when saturated with humidity, becomes so heavy and compact as to be not easily washed away. The impetuosity of the mountain torrent undermines the fast-decomposing rock, and frequently brings down large boulders and loose stones, which, dashing against the sides of the ravine, are in no small degree instrumental to its destruction.

Not less important are the changes going on in the high range, since the time of their formation. Ice is of so uncommon occurrence, that we can scarcely attribute to it any considerable cooperation; but the action of water is materially a.s.sisted by occasional earthquakes. Gradual decomposition and decay has produced on the base, and produces still, conglomerates of various thickness and extent. The high plateau enjoys a thick coat of fertile black soil. Lakes, pools, mora.s.ses, and swamps, are frequent; the rivers of little fall have muddy and miry beds, which on that account become unfordable during the rains.

A few hot mineral wells are known and made use of in Efat and Giddem.

Precious metals and precious stones have not yet been discovered; but of useful mineral products, iron, sulphur, and coal, are the princ.i.p.al.

Iron ores are the riches of the high plateau, the oxy-hydrate being the best of them. Enclosed in the basalt, it comes to view only in the ravines, whence it is sc.r.a.ped out. From the western borders of the Adel country, and from the extinct volcanoes of Mentshar, is derived the small supply of native sulphur required; the pits are described as exceedingly copious. Coal-beds appear to extend along the whole of the eastern frontier of Shoa; but the combustible nature of the fossil is scarcely known in the country. Copper, tin, zinc, and salt, are all imported into Shoa; the Adaiel possessing the last commodity in abundance. The Shoan clay proves a very indifferent material for the manufacture of earthenware. Excellent quarries could be worked, but the primitive fashion of the dwellings is independent of the use of stone.

Botany.

The provinces that compose the kingdom of Shoa enjoy not only political but also natural and physical boundaries. From the luxuriant vegetation, or the parched-up desert of a tropical clime, we suddenly ascend to regions where the blessings of fertility are more equably diffused, and which serve as granaries to the inhabitants of the lowlands.

From the general nature of the rocks, it is obvious that the soil consists chiefly of decomposed feldspar, which requires abundance of water. Dews, rains, and springs, however, so moisten the mountain side, that artificial irrigation need be resorted to but on few localities.

Along the foot of the hills, rude channels, dug out of the sandy or gravelly soil, conduct abundance of water to plantations at a distance from the river side; and, in these lower regions, periodical inundations supply the want of rain.--

It is an established fact, that the _cryptogamic plants_ of cellular construction, are in different zones nearly the same. Under similar circ.u.mstances the same lichen covers the face of the rock in Europe as in the continents of the torrid zone, the same mould lines decaying matter, and the same fungus cleaves to bark and root. But, compared with the other orders of plants, the cellulars are most defective in numbers throughout Abyssinia, the peculiarities of the climate being very unfavourable to their development.

Every kind of parasitic plant is looked upon with a suspicious eye in Abyssinia; and those of the vascular orders furnish to the conjuring pract.i.tioner his princ.i.p.al remedies. But the mushrooms (_Demastafi_), the fungi and puff-b.a.l.l.s (_Ya arrogie siet phis_), are believed to pollute the finger that touches them, and to be downright poison.

Mould, of course, thrives exuberantly on every substance in so moist a climate as that of Shoa. The blight is but too well known; the _Boletus igniarius_ grows abundantly in the forests; _Parmeliae_ and other lichens cover rocks, or depend fantastically from the withered branches of gigantic trees. _Mosses_, however, are very scarce, and only of four kinds.

The _vascular acotyledonic plants_, the ferns, might likewise be expected in greater variety among the Abyssinian weeds than is actually the case. The deep recesses of the few remaining forests harbour some kinds which very closely resemble European forms, and belong to the genera _Aspidium, Polypodium, Asplenium, Adiantum, Scolopendrium, Ophioglossum_, and _Pteris_. No tree is among them, nor are the Abyssinians aware of the useful properties of the tribe. _Adianthum Capillus Veneris_ is called in Amharic "_Sera Besoo_" i.e. much work-- finely wrought.

Of the four orders into which the tribe of _monocotyledonic plants_ is naturally subdivided, viz. the Gra.s.ses, the Lilies, the Orchides, and the Palms, the first undoubtedly deserves our princ.i.p.al attention, for it is by far the most numerous and important. The great elevation of the Abyssinian plains is so favourable for the cultivation of all _Cerealia_ of the temperate zone, that they may rival the very best agricultural districts of Northern Europe, whilst the low country along the foot of the mountains produces some kinds of tropical grain, and would fully answer for the cultivation of rice, which at present is unknown in the country.

The Abyssinian husbandman takes great trouble in improving the cultivated sorts of grain, by changing the seed-corn at every season, and sometimes by sowing promiscuously different sorts to produce new varieties. Hence the astonishing number of distinguishable kinds cultivated in a small compa.s.s of ground under certain established appellations, and brought into use for very different purposes. Within a circ.u.mference of five miles around Ankober are found, of juwarree, 28 varieties; of wheat, 24; of barley, 16; of rye, 2; of teff, 4; of oats, 2; of maize, 2. Various kinds of bread and cakes are prepared from some of these; malt for beer is chosen from others; and the inferior kinds are given to slaves and cattle.

The existing meadow-gra.s.ses answer so well, that an introduction of new species, or a regular culture, is not attempted. In times of great famine the seeds of some of these gra.s.ses come into use as food. In the swamps and humid meadows, and in many rivulets, species of Cyperus and Scirpus are very frequent, some of which attain immense height, being used for thatching, or in the manufacture of baskets, mats, etc.

Papyrus also grows in the low countries of Efat.

The following species of gra.s.ses and grain are cultivated: Lorghum vulgare (_Mashila_), the Juwarree of India, and Durrha of Arabia, in many varieties, the princ.i.p.al of which are: a (_Sengada_), with red spreading spike; b (_Wogari_), with yellow, compact pendent spike. The young stalks contain a great deal of saccharine, and are chewed: they attain, in good situations, the enormous height of eighteen feet. The produce of Efat and Giddem in this grain is chiefly exported to the countries of the Adaiel; but a small quant.i.ty comes to the Shoan marts for inferior kinds of beer, unleavened bread, and the food of mules. In Shoa itself Mashila cannot be raised on account of the low temperature.

Saccharum officinarum, the sugar-cane (_Shonkar_), is also planted to a small extent in the low country. The art of making sugar being unknown, it is only chewed; and although regarded a great luxury, and sent in token of friendship by the great, no particular care is bestowed upon improving its growth.

Elusine Tocussa (_Dagusa_), a minute grain in quarternaire crosswise disposed spikes, is produced on a low gra.s.s extensively cultivated in Northern Abyssinia; and the Emperor of Gondar is said to be forced by etiquette to eat cakes of it, to the exclusion of other farinaceous food.

Poa Abyssinica (_Teff_). This millet-like seed is a favourite with all Abyssinians, although the bread made of it is extremely unwholesome and insipid. Four varieties are found, two of a brown, and two of a white kind. The latter has the preference; and the finest, called _Manya Teff_, is grown only upon the king's fields, and can never be purchased by the subject. The straw of the _Teff_ is regarded the best stable-fodder.

Zea Maize (_Mar Mashila_), i.e. Honey-sweet Mashila, is princ.i.p.ally eaten when fresh and milky. A little roasted it is a most acceptable offering to the visitor. Sixteen kinds of barley (_Geps_) are raised on the hill-tops, and on the high plateau of the Galla country, where neither juwarree nor wheat will thrive. Its greatest consumption is in brewing, but mules and horses are also fed on it, and the finer sorts are eaten (_Mariam Sahr Litch Alkuso Sandarash). Barya Settat_, i.e.

"the slaves' portion," as might be imagined, is not of first-rate quality.

Secale cereale (_Damash Sanaf Kolo_) finds a limited consumption, mixed with other flour in bread.

Tritic.u.m aestivum, hibernum, etc. (_Sendi_). Shoa can boast of twenty-four varieties of wheat. Many of these were originally cultivated by the Galla, and subsequently introduced. The other provinces of Abyssinia have also furnished various kinds; but the most esteemed are indigenous, viz. _Y'abuna ehel, Ya beri mangada, Ya gosh gumbar_, i.e. "Aboon's grain;" "bullock's molar tooth;" "buffaloes'

forehead." Wheat is frequently eaten unground, in a mixture of parched grain, called _Kolo_, which is the only store carried by the Amhara warrior into the field.

Avena spec. (_Gherama_) is a small kind of oats, sown on the poorest fields, in order that favourite mules and horses may crop it while yet green. In times of scarcity the poor are compelled to resort to it.

Bambusa arundinacea (_Shemal_). The bamboo is not indigenous in any part of the country, but groves are planted on the king's grounds, in order to supply poles for the royal tents.

The following are the gra.s.ses found in every pasture:--Lolium temulentum (_Enkerdad_), much dreaded as poison; Chloris spec. (_Agerma_); Andropogon distachyum (_Gasha_); Anthistiria spec. (_Sambalet_); Sporobolus spec. (_Ya teff sahr_) the seeds eaten as those of the teff; Poa brizoides (_Ya Kiri sahr_); Kiri is a species of finch, which eats the small seeds; Setaria spec. (_Ya oosha Sendado_).

The next order, that of the _Lilies_, is not so numerous as might be expected of Africa, but when a species does appear, it covers vast tracts with its lovely colours. None but the edible kinds of Allium are cultivated in Abyssinia, ornamental gardens being quite unknown throughout the country. Some grow in swampy meadows, especially those with bulbs, more properly ranking as lilies: others, with perennial stem, are found on dry waste places, such as the Asparagus and the Aloe.

The whole year round, the meads are graced by the lovely blossoms of two Commelineae, viz. Commelina Africana, and Tradescantia spec. Both having small oval tubers, they are called _Off angoon_ and _Off gola_, i.e. "bird's egg" (_off_, a bird; _angoon_ and _gola_, or more commonly _angola_, an egg). These tubers are eaten in times of famine. One ixia, a very beautiful kind, of the mora.s.ses around Angollala, springs up immediately after the termination of the rains. Haemanthus coccineus, Amaryllis clavata, Gloriosa spec, are rare plants of Efat; Bulbocodium spec, is a very transient form, observable a few days after the "rains of Bounty." Onions and garlic (_Neitch Shongort_) are favourite vegetables; various kinds of Aloe (_Ya jib Shongort_) adorn the wastes of Efat, and furnish good fibres for making ropes. Asparagus retrofractus (_Sareti_), and Asparagus Ethiopicus (_Kastanitcha_), are fructiferous and climbing shrubs: a green twig of the first, stuck in the hair of the sinciput, is a token of exultation after a successful encounter with an enemy or wild beast; the wood of the second is of peculiar hardness, and splitting well serves the Amhara scribe as a pen.

Lastly, one Smilax (_Ashkila_) affords the stick in common use as a tooth-brush.

That equally beautiful and important order, the _Orchideae_, might be supposed to find its natural ground in Abyssinia, where both atmosphere and soil are so favourable; but ginger is still imported from Gurague: arrow-root and salep are unknown, and not a single kind of the respective genera is an inhabitant either of Shoa or Efat. The real _Orchideae_ of the forests, moreover, are few in number. Epidendrum capense, cleaving to the bark of the wild olive-tree, is the only representative of that interesting group, the _Epidendreae_. Of the plantain tribe, three species have been introduced from the south, but apparently with little advantage; viz. _Mooz_, Musa paradisiaca, a coa.r.s.e kind of plantain, which is reared on some few spots in Efat for the royal table, and two species of Urania, called _Ensete_ and _Koba_.

These are planted in Shoa for the sake of their leaves; they seldom advance to flower and fruit, in consequence of the low temperature. The only visible difference between them is, that in the Koba the middle rib of the leaf is on the underside red, as also the stem; whilst in the Ensete both are light green. Either of these trees, when suffered to grow, attains a height of twelve feet in the stem, exceeding by far that of the Mooz; the leaves are equal in size to those of the latter, and are only used to bake bread upon. Their proper home is Gurague, the famous seat of so many botanical riches. Seed-capsules of the Koba brought from that country contain four or five angular nuts, full of a mealy substance, like the finest arrow-root, which is boiled and given to children to make them grow; the base of the fruit is filled with a delicious pulp like that of the plantain. In Gurague the young shoots of the Ensete form a princ.i.p.al part of the diet, but they are despised by the Amhara, who are not at all addicted to vegetables. The fibres are used in the manufacture of ropes and mats, which form an important article of trade with Shoa. Ensete and Koba are hardier than the Mooz; and towering above the enclosures of the lofty villages, impart an aspect not properly belonging to the landscape, and strangely contrasting with many alpine a.s.sociates.

The _Palms_ of the continents of the eastern world are, with very few exceptions, inhabitants of the sea-borders, and do not thrive at any considerable elevation or even distance inland. The coast of the Adaiel is therefore the only locality where three species of this tribe, viz.

Phoenix dactylifera, Hyphaene crucifera, and Bora.s.sus flabelliformis, appear; but so scantily, that the date must be imported from Arabia.

Baskets and mats are manufactured of the leaves of all, and some toddy is prepared of the Bora.s.sus especially.

The preceding enumeration of acotyledonic and monocotyledonic plants is not sufficient to determine the systematic place due to the Abyssinian vegetation in general. The Dicotyledones, comprising two-thirds of all the plants, will necessarily help to show, that although included within the tropics, the Flora of Shoa, and of some of the Galla provinces to the west, is, on the whole, subalpine. The avenues of approach to them from the eastward, evince in their scanty dress the influence of a tropical sun; and between these two extremes, a happy and most fertile province intervenes, where, by the side of the hardy grain, cotton and coffee may be raised--where a tea-plant and many species of indigo grow wild--and where, in fact, a temperate and a torrid clime exchange their products as it were upon neutral ground.

The _Chlamydoblasta_ number but very few species in Abyssinia. One Nymphaae only, on the lakes of Shoa, and one Aristolochia (bracteata) of the Adaiel country, could be discovered. This latter, called _Gerbaad_, is a secret remedy with the Danakil against poisoned wounds, and in fact they are p.r.o.ne to attribute mysterious qualities to the most of their weeds. Pepper is not found either in a wild or cultivated state, although nothing would oppose the introduction of that favourite condiment, which at present, under the appellation of _Gunda Berberi_ (_Gunda_, an ant; _Berberi_, hot spice) is imported from Arabia and India.

Of _apetalous Gymn.o.blasts_, some important species are to be recorded, since they form the chief pride of the forests. And justly beginning with the Coniferae, the fir (cedar), which graces the Alps of Northern Abyssinia, is replaced in Shoa by a gigantic juniper, Juniperus excelsa (_Det_). This n.o.ble tree of the woods as well as of the churchyards attains in its life of one century a height of upwards of one hundred and sixty feet, with four to five in diameter at the base. Growing nearly in the shape of a cypress, it throws off continually the lower branches, which shoot out almost at a right angle from the stem, so that two-thirds of the same are void of green; the top is always a pyramid, and generally scanty. The wood is very inferior, but splitting readily, it supplies, in the absence of proper carpenters' tools, the chief timber used in the construction of huts and churches; and it forms, besides, the common fuel. Neither is any use made of the resin or berries; but twigs lopped off the melancholy trees that overshadow the cemetery, are often strewn upon the corpse before the grave is filled up. A yew tree, Taxus elongata, _Sigba_, also of the Shoan forests, keeps within more moderate dimensions; sixty feet in height, and five in circ.u.mference, is the utmost. The tough wood, like that of the wild olive-tree, furnishes the timber for works of art which are to last some time. To tarry beneath its shade, or to inhale the smoke of burning yew wood, is regarded as particularly noxious.

The low temperature reigning in the Alps of Abyssinia does not prohibit the growth of a species of fig, which contrasts strangely enough with the tall juniper. The _Shoala_, a kind of Banyan tree, with large, oval, acute, serrated, and subcordate leaves, and racemes of fruits attached only to the stem and princ.i.p.al branches, measures frequently seven feet in diameter, with a height of forty feet, at an age of two-score years. Its roots are partly above ground; but of secondary, or branch-roots, there is no vestige. Requiring no small s.p.a.ce for expansion, it stands commonly on the outskirts of the forests, or quite alone, but its shade is extremely dense and unfavourable to other vegetation. The fruit, of the size of a pigeon's egg, brown and insipid, might be eaten by people in distress. In the low country the Sycamore Fig-tree makes its appearance; it is called _Worka_, i.e. "the Golden," by the Amhara, and _Woda_ by the Galla; and has, with those of the latter nation, who are still in the bonds of idolatry, a sacred signification. Being planted over the tombs of notable persons, conjurers, or heroes, offerings are brought to it, and hung up on the branches at certain festivals, when the neighbouring tribes feast together upon that holy and neutral ground. The Worka stands always near running water, towering far over the jungle, although the undivided stem is scarcely ten feet high. The leaf has a yellow tomentum below; and the fruit forms a favourite food of monkeys and of various birds, but is not touched by man.

The _Kuaraf_, Gunnera spec, another plant of the same family, of _Artocarpeae_, is an important vegetable during the strict fast of Lent.