Page:Encyclopædia Britannica, Ninth Edition, v. 5.djvu/268

Rh 256 CAUCASUS steppes and plains of Russia on the north side of the chain are open to the cold winds of the north, and partake to a great extent of the severity of a Russian winter ; while the valleys of Imeritia and Georgia on the southern side are sheltered by the vast mountain wall to the north of them, and thence enjoy a climate more in accordance with their southerly latitude. Thus Tiflis, though situated at a height of about 1500 feet above the sea, has a mean temperature of 55, and Kutais of more than 58 U. The average winter temperature of Tiflis does not fall below 36, and that of Kutais is not less than 42 5. But a still more remarkable contrast is that presented by the varying amount of rainfall in the different portions of the chain, according to their distance from the Black Sea. While the rainfall at Tiflis does not exceed 20 inches, it amounts to more than 57 inches at Kutais, and not less than 63 inches at Redut Kaleh on the sea shore near Poti. The effects of these great variations in the meteorological conditions of the countries adjoining the Caucasus are naturally striking and strongly marked. Whatever be the contrasts presented by the two sides of the Alps, they are Vegetation far more remarkable in the Caucasus. This is especially and the case with the south-western valleys and slopes, where a ncI 7- great amount of rain is combined with a warm tempera ture. Hence all this part of the mountain country is characterized by a luxuriance of vegetation to which no parallel can be found in Europe. Magnificent forests clothe the mountain sides and extend down quite to the sea; while the rich valley, or rather basin, of the Rion equals any part of Italy in fertility, and is capable of producing ail kinds of crops that flourish in the Italian plains. But as the traveller passes inland towards Tiflis, he is struck by the change that takes place after crossing the comparatively trifling range of the Suram Mountains. Arid upland plains and parched hill-sides take the place of the rich verdure and luxuriant forests of Imeritia and Mingrelia. A similar change is observed in the higher regions of the mountains on crossing the Mamisson Pass, which separates the head waters of the Ardon from those of the Rion. While the valleys west of this especially that of the upper Ingur, or Suanetia are covered with the richest vegetation, those on the other side, the valleys of the Ardon and Terek, are almost wholly bare of trees, and present only mountain slopes covered with grass, where they are not sheets of bare rock. The extensive pine forests, which constitute so important a feature in the scenery of the Alps, are almost wholly wanting in the Caucasus, or at least of only partial and occasional occurrence ; and the description given by Mr Freshfield of the scenery of the Terek above Kazbek, that it presents &quot;treeless valleys, bold rocks, slopes of forbidding steepness (even to eyes accustomed to those of the Alps), and stone-built villages, scarcely distinguishable from the neighbouring crags,&quot; will apply with little varia tion to all the valleys that run northward from the central chain. But if the general scenery of these valleys be dull and uninteresting, there is a marked exception in the deep gorges by which in most cases their waters make their escape through the northern lateral ridge. These defiles are pronounced by competent judges to be far superior in grandeur to anything of the kind to be found in the Alps ; that of Dariel has been already described, but the less known gorges of the Tcherek and the Uruch are considered by recent travellers to be still more striking and marvellous. At the same time the snowy ridges and peaks of the central chain are said to surpass those of the highest portions of the Alps in boldness and picturesqueness of outline, as well as in steepness and apparent inaccessibility, as much as they do in absolute elevation. On the whole it may be safely asserted that the Caucasus presents attractions to the traveller and the tourist beyond those of any other mountain chain within such comparatively easy reach, and that it will year by year become better known and more frequently visited. The vegetation of the Caucasus is in general not materially different from that of the mountain chains of Central Europe. The extensive forests that clothe its flanks are composed entirely of the ordinary European trees, among which the oak, the beech, the elm, and the alder are the most prevalent, but a peculiar character is imparted to them by the dense undergrowth of rhododen drons, azaleas, box-trees, and laurels, as well as by the huge climbing masses of ivy, clematis, and wild vine, which attain to a height and size wholly unlike anything to be seen in Western Europe. Fruit trees of various kinds abound on the lower slopes of the hills, where the plum, the peach, the apple, and the pear are found wild, as well as the walnut, which is extensively grown in the cultivated regions, where it combines with the plane and the lime tree to form one of the chief ornaments of the landscape. The wild animals found in the Caucasus are Zoology, for the most part the same with those of the mountainous regions of Central Europe, while others point to a transi tion toward the zoological character of Asia. Thus while it has the bear, the wolf, the wild boar, the lynx, in common with the Alps, the jackal is not unfrequent on its southern side, the hyasna is also found, and leopards are occasionally killed. Tigers do not appear to be ever found in the Caucasus proper, though they are killed from time to time in the districts of Lenkoran on the Caspian, south of the mouth of the Kur. The ibex or bouquetin, as well as the chamois, abounds among the higher summits of the range, and with them is found the wild goat (Capra Jtgagrus), and a species of moufflon or wild sheep. These vast forests of the western ranges still afford shelter to the aurochs or European bison, which now exists here alone in a truly wild state. It may be mentioned also that the southern slopes of the Caucasus are the native country of the pheasant, which derives its name, as well as its origin, from the River Phasis. Geology. The geology of the Caucasus is still but Geology. imperfectly known, though the long-continued labours of Dr Abich have thrown much light on the subject, and enabled us to trace at all events its general outlines. Throughout the most lofty part of the chain, from beyond Elbruz on the west to Kazbek on the east, the central ridge is composed of rocks of a granitic character; in great part indeed of pure granite. Immediately adjoining this granitic axis are found metamorphic rocks of the usual character, mica-schists, talc-schists, &c., and beyond these, again, clay-slates and schists of uncertain age. The great limestone masses that form the secondary chains on each side of the central range (which rise to a height of 10,000 to 12,000 feet) are considered by Dr Abich to belong to the Jurassic formation, while the flanks and underfalls of the mountains on both sides are composed of Cretaceous strata, and these are again succeeded by Tertiary marls and sandstones, extending around the base of the chains, and forming its lowest declivities. This succession of the strata may be observed with great regu larity and distinctness on the north side of the range, and is found on the southern side also, though more disturbed and irregular. The principal disturbance on the north side is caused by the protrusion of the two great masses of Elbruz and Kazbek, both of them of decidedly volcanic origin, and (geologically speaking) of comparatively recent date. They are composed principally of trachyte, but send down also vast streams of basaltic lavas, which form a striking feature in the scenery of tlie valleys beneath them. The regularity of structure which may be considered as pervading the whole of this central mass of the Caucasus