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Kara Kala projects from the parapet some little distance towards the north, at the head of its meridional ridge. But this feature is not observable from the southern side of the mountain, where the rampart is seen to pursue its long, straight course. The gradient of the southern slope increases as you approach Demir Kala, but does not exceed 23°. The platform along the summit gradually narrows, until in Demir Kala it becomes an upstanding mass of blocks of lava which must be climbed, stepping from block to block. The lava, which east of Kara Kala has shown traces of obsidian, is somewhat scoriaceous and in places weathers a brick red.[4] The summit is flat and fairly free of boulders, which, however, are piled in a beach further east. The level at Demir Kala (10,770 feet) is fairly well maintained for some distance, and produces the bold effect of the horn on the east. But the cliff, after turning northwards, soon comes to an end, being separated from the bank-like continuation of the horn by a narrow but passable cleft. This long, meridional bank composes the eastern wall of the eastern cirque, which is bounded on the west by the medial ridge from Kara Kala. The character of the rampart in this eastern basin is much the same as in the western cirque, although more uniform in point of height. From the south it has the appearance of a straight and gently vaulted bank; from the north, that of a curved outline with steep cliffs.
Just as Bingöl Kala is joined on the south to a meridional ridge, so is Demir Kala in connection with another such outside parapet, which continues the main rampart in a south-easterly direction, far beyond the limits of the cirque. This parapet is beautifully vaulted on the south-west, where it determines the drainage of the Gumgum Su. But on the north-east it breaks away to the grassy ground outside the basin with piles of boulders which are somewhat difficult to cross. Indeed it was always a most laborious matter to reach the eastern cirque from our camp. If we took the pass between the western summit and Kara Kala, there was the medial ridge, with its beach-like terraces, to surmount. If, on the other hand, we made our way up the south-western face of the outer parapet, we encountered the difficult descent on the north-eastern side, and, when this feat had been accomplished, we were obliged to ride a long way north before it became possible to cross the bank which confines the basin on the east. For a man on foot it is feasible to descend the cliffs of the main rampart at several points, and a horse may scramble through the cleft formed by the break-off on the north of the wall of the eastern cirque. But such an attempt is not less dangerous than the endeavour to lead an animal up the snow-slope in that cirque. It seems an easy matter; for the snow extends from the floor of the basin to the edge of the cliff, which at the time of our visit was free from snow. But it nearly cost us the lives of a zaptieh and several horses. When the gradient was at its steepest the snow gave way, and the manner in which one horse by a series of plunges reached the summit was a remarkable example of the power of nervous energy.
It is plain from this description that the conception of the mountain, as seen from the north, is likely to be considerably enlarged and modified by a visit to its southern side. Instead of a single ridge we have a series of ramparts, which describe a figure somewhat resembling an H. The transverse bar of the letter represents the main parapet with the three summits, Bingöl Kala, Kara Kala and Demir Kala. The two uprights will correspond with the horns of the basin on the north, and with the connecting ramparts on the south. A medial projection should be added to the transverse bar, in order to include the meridional ridge from Kara Kala. Finally the upright corresponding with the northern horn on the west should be split into two short arms. Of these the inner arm will represent Aghri Kala.
At the risk of becoming tedious, I have thought it well to insist on these features, in order that our statement may enable the practised reader to judge for himself whether Bingöl ought to be regarded as a volcanic crater in the strict sense of the word. Before adducing additional facts, which may point to a negative conclusion, I should like to mention the explanation which appeared to us on the whole more probable of the phenomena with which we are dealing. It is evident that the latest emissions of lava were much more acid and viscous than those which produced the plateau surface of the surroundings of Bingöl. If we assume that all these lavas issued from fissures rather than from a crater, then the formation of such ramparts in the final stages may be readily explained. The molten matter, welling up from its original vents, became too viscous to flow far. It massed in the form of vaulted ridges along the axis of the parent fissures, or in their neighbourhood. I have already noticed the rounded nature of these various ramparts when seen from the south, as from the standpoint of our second camp. The transverse parapet with the principal summits has the appearance of a long, straight bank, flanked at its extremities by two similar banks, which project towards the south like wings. Look where you will, the slopes are gentle, and strewn with fragments of lava, which in some places have the appearance of loose tiles. Within the figure, thus formed, rise the head waters of the Gumgum Su, collecting, with a network of streams, both from the west and from the east. They combine at the head of the great chasm, to flow through its shadowed depths towards the plain.
It is true that this vaulted and bank-like appearance of the ramparts is not characteristic of any of the slopes towards the north. Indeed the exact contrary is the case. But at this stage of the enquiry we are introduced to a feature which is perhaps the most remarkable of all these phenomena, and which it is surprising that none of our predecessors should have observed. When I descended for the first time into the western cirque, Oswald, who had been engaged there in taking measurements with the telemeter, pointed out to me evident traces of the action of ice. Quite close to the cliff on the south the bosses of lava within the basin have been worn by a glacier moving towards the north. Smooth on top, and with an almost flat surface upon the south, they are rough and precipitous on their northern sides. The rock is very distinctly striated, the striæ pointing in a northerly direction. The feature continues and gains in definition as you follow down the cirque. Between the bosses the ground is covered with turf and oozes with water, which collects in pools or little tarns. Blue gentians are found in abundance within these peaty hollows, while the violets scent the air in the neighbourhood of the snow. Some distance further, when you are already outside the limits of the cirque, and have reached a level of about 9000 feet, the moraines commence to form. We visited this district from the west, and made our way in an easterly direction across the moraines. They were seen to consist of a medial and two lateral moraines, of which that in the centre proceeds from the extremity of the meridional ridge from Kara Kala, and must have separated two glaciers, issuing one from either cirque (Fig. 193). The lateral moraine upon the west seemed about in a line with Aghri Kala; but a branch of the glacier must have flowed towards north-west, for the extremity of that ridge has been cut down by the stream of ice. This moraine is so pronounced that it is difficult to realise that there are now no longer glaciers on Bingöl. On both sides it is bounded by a lofty embankment of blocks of rock, embedded in soil. The summit, which is broad, bristles with upstanding boulders, and in the hollows there are a number of lakes and pools. A stretch of level and grassy ground is interposed between this rampart and the medial moraine, which shows a similar embankment on its western side. A little river, collecting the drainage of the western cirque, flows in the trough of this grassy depression. The lateral moraine upon the east is in fact that great fan-shaped bank, which extends northwards from the horn of the eastern cirque. Again in this basin a branch of the glacier has diverged, and broken its way through the cleft in its eastern wall. The floor of the cirque is much more grassy than that of its neighbour on the west, but the masses of rock are striated in a similar manner.
Fig. 193. The so-called Crater of Bingöl from about the centre of the Moraine from Kara Kala
The principal reservoir for the ice and snow has been the broad platform between Kara Kala and the western summit. Thence have issued towards the north extensive fields of moving ice, while the melted snow has poured into the hollow on the south of the platform and has carved down the great chasm. We could not trace the action of ice upon the rocks in that direction. I do not know whether we should be justified in dating the disappearance of these glaciers as far back as the glacial epoch. Striking evidence of the existence of a glacial period in these countries has been collected by a modern traveller in the highlands with their marginal region on the side of the Black Sea.[5]
We are therefore justified in assuming that the abruptness of the ramparts on the north, as well as the carving out of the main ridge into cirques, is largely due to the erosive action of ice. Leaving this subject, I would ask my reader to follow us in an excursion to the interesting region on the south of the mountain. For perhaps the most remarkable characteristic about Bingöl is the great plateau which it has contributed to form; and the features of that plateau which engrave themselves most deeply into the memory are the towering cliffs with the chasm on the south.