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 geography] AFGHANISTAN 117 (the Band-i-Amir) within the folds of the Kara Koh to the above the sea-level. Then the ocean gradually retired into Kunduz, and beyond ; but the Kara Koh does not mark the northern wall of the great plateau nor overlook the sands of the the great Central Asian depressions. Oxus plain, as does the Band-i-Turkestan. Here there intervenes Everywhere there have been great and constant changes of a second wide synclinal plateau, of which the northern edge is level since that period, and the process of flexure and the formadefined by the flat outlines of the Elburz to the south 6f Mazar-i- tion of anticlinals traversing the northern districts of Afghanistan Sharif, and immediately at the foot of this range lie the alluvial is a process which is still in action. So rapid has been the land flats of Mazar and Tashkurghan. Opposite Tashkurghan the elevation of Central Afghanistan that the erosive action of rivers Oxus plain narrows to a short 25 miles. On the south this great has not been able to keep pace with that of upheaval; and the band of roughly undulating central plateau is bounded by the result all through Afghanistan (but specially marked in the great Koh-i-Baba, to the west of Kabul, and by the Hindu Kush to the central highlands between Kabul and Herat) is the formation of north and north-east of that city. Thus the main routes from those immensely deep gorges and defiles which are locally known Kabul to Afghan Turkestan must cross either one or other of as “ daras.” One of these, in the Astarab, to the south-east of these ranges, and must traverse one or other of the terrific defiles Maimana, is but 30 yards wide, and is enclosed between perpenwhich have been carved out of them by the upper tributaries of dicular limestone cliffs 1500 feet high. Throughout Afghan the rivers running northwards towards the Oxus. Probably in Turkestan and Afghanistan the lowest beds belong to a marine no country in the world are there gathered together within com- Carboniferous era. These are overlaid by a long succession of paratively narrow limits so many clean-cut waterways, measuring strata, partly marine and partly fluviatile, forming an unbroken thousands of feet in depth, affording such a stupendous system of series up to Jurassic times. On the upturned and denuded edges narrow roadways through the hills. of these strata enormously thick beds of Cretaceous limestone rest After the Hindu Kush and the Turkestan ranges, that of the unconformably; above these, again, marine and freshwater deposits Safed Koh, which divides Kingrahar (or the valley of Jalalabad) are spread. Griesbach considers that the general outline of the from Kuram and the Afridi Tirah, is the most important, as it is land configuration has remained much the same since Pliocene the most impressive, in Afghanistan. But the general features of times, and that the force which brought about the wrinkthe Safed Koh have been sufficiently described already, and it ling of the older deposits still continues to add fold on fold. only remains to illustrate its configuration in relation to the The highlands which shut off’ the Turkestan provinces from mountain systems about Kabul, and south of Peshawur. The Southern Afghanistan have afforded the best opportunities highest peak of the Safed Koh, Sikaram, is 15,600 feet above for geological investigation, and, as might be expected from sea-level. From this central dominating peak it falls gently their geographical position, the general result of the examinatowards the west, and gradually subsides in long spurs, reaching tion of exposed sections leads to the identification of geological to within a few miles of Kabul and barring the road from Kabul affinity with Himalayan, Indian, and Persian regions. The to Ghazni. At a point which is not far east of the Kabul meridian general configuration of the Turkestan highlands has been already an offshoot is directed southwards, which becomes the water- indicated. Against the last great fold which terminates this parting between the Kuram and the Logar at Shutargardan, and mountain area northwards are ranged the Tertiaries and recent can be traced to a connexion with the great watershed of the deposits. North of Maimana they form low undulating loess hills, frontier dividing the Indus basin from that of Helmand. This in which most of the Band-i-Turkestan drainage is lost. This widemain watershed retains its high altitude far to the south. There spreading loess area, formed partly of wind-blown sand and partly are peaks measuring over 12,000 feet on the divide between the of detritus from the mountains, is known as Chul, and merges into Tochi and the Ghazni plains. At the eastern extremity the the great plains south of the Oxus river, a great part of which is Safed Koh splits and spreads into several branches. Between covered with modern aerial deposits. Beneath this Chul formation these branches are the Bazar valley ; the Bara, which receives the older beds of the outer and Turkestan ranges dip and pass to the Maidan drainage ; the Khanke, and other lesser valleys. an irregular outcrop near the banks of the Oxus. Between the The Afridi Tirah is but an upland basin held within the arms of Oxus and the hills there has already been formed a rise or flexure some of the minor Safed Koh spurs, which, from the peculiarity in the ground, which extends more or less parallel to the northern of its formation and its narrow drainage outlet, contains a vast edge of the hills, and, shutting in the cultivated area of the depth of highly fertile alluvial soil. plains, arrests all tributaries seeking to effect a junctmn Between the Safed Koh and the Gomul (where lies the official with the Oxus from the south, and leads to the formation of boundary of Baluchistan) the frontier mountain system is more marshes and swamps. This appears to be the commencement of irregular than it is south of that river, where an invariable a new anticlinal which has altered the levels of the Balkh plain, system of close parallel flexures predominates. The first develop- and is. indicative of those elevating processes which may have ments of this system are recognizable in the long straight ridges been effective within historic times in changing the climate and trending from north-east to south-west, which may be seen to the west the agricultural prospects of this part of Central Asia. The Oxus of the peaks heading the Waziri group, forming the dividing line of itself is steadily encroaching on its right banks and depositing the Indus basin. But this configuration is not so apparent in the detritus on the left. Waziri hills or in those between the Kuram and the Kaitu, where No fresh discoveries of minerals likely to be of high economic the mountains are massed in more independent and isolated value to Afghanistan have been made of late years. Such as are groups, facing steeply westwards and culminating on their known and worked at present have been worked from very ancient western summits in peaks 11,600 feet above sea-level. But the times, and their capacity is not likely to develop greatly under same conformation of crumpled limestone ridges, overlaid with the Kabul Government. The most important feature in this Tertiary deposits, which pervades all Afghanistan and Balu- connexion which was noted by the geologist of the Russochistan, prevails also throughout Waziristan and determines its Afghan Commission is the existence of vast coal beds in general outlines. The extension of a long ridge towards the Northern Afghanistan. Indus, which curves in a grand sweep northwards overlooking the There are no glaciers now to be found in Afghan Turkestan ; river, introduces a welcome break into the monotonous regularity but evidences of their recent existence are abundant. The great of frontier scenery. On this ridge is the frontier hill station of boulder bed terraces in some of the valleys of the northern slopes Sheikh Budin. of the Ferozkhoi plateau are probably of glacial origin. In the mountains west of Kabul glaciers have retired, leaving the Geology.—So far as we know at present the geological moraines perfectly undisturbed. They were probably cotemporary history of Afghanistan differs widely from that of India. with the older alluvia. When, somewhere at the commencement of the Cretaceous Climate.—Over an area so large as Afghanistan, involving period, the peninsula of India was connected by land with such varied conditions of geographical conformation, we find, Madagascar and Southern Africa, all Afghanistan, Balu- as we might expect, a varied climatic record. Taking the chistan, and Persia formed part of an area which was not highlands of the country as a whole, there is no great perhaps continuously below sea-level, but which exhibited difference between the mean temperature of Afghanistan alternations of land and sea. The end of the Cretaceous and that of the lower Himalaya. Each may be placed at period saw the commencement of a series of great earth a point between 50° and 60° F. But the remarkable movements ushered in by volcanic eruptions on a scale feature of Afghan climate (as also of the climate of Balusuch as the earth has never since witnessed, which resulted chistan) is its extreme range of temperature within limited in the upheaval of the Himalaya by a process of crushing periods. The least daily range in Northern Afghanistan is and folding of the sedimentary rocks till marine fossils in the cold weather, the greatest in the hot. For seven were forced to an altitude of 20,000 feet above the sea. It months of the year (from May to November) this range was not till the Tertiary age, and even late in that age, exceeds 30° F. daily. The coldest month of the year that much of the land area of Afghanistan was raised is February, the mean minimum being 17° F., and the