ABICh's geological sketches beyond the CAUCASUS. 43 



the Agmangan table-lands. The most important streams taken up by 

 the Araxes in its course through the elevated plain, viz. the Akurean, 

 Abarran, Garni, Wedi, Arpatschai and Makutschai, rise at once as 

 Karasu waters from the volcanic deposits of the hills and plains. 



Those rivers are in fact the real arterial feeders of luxuriant vege- 

 tation, and by means of the venous system of the canals at the mouths 

 of the valleys, are the sole causes of the cultivation and fertility of the 

 darker soil of the plain of the Araxes. Its abundance of water is the 

 gift of the volcanic energy of times antecedent to history. We may 

 partly understand what the plain of the Araxes would be without those 

 volcanic uplands with their mighty springs in the bosom of the moun- 

 tains, by considering the desert and steppe-like character of those 

 districts which are spread out before the entrances of other valleys, 

 the upper ends of which do not, like the former, extend into the vol- 

 canic table-lands, as e. g. the valley of Wazargach, between the val- 

 leys of the Arpatschai and of the Sardarack. These valleys, arid and 

 deserted, are not watered by perpetual streams ; stones and gravel 

 have artificially raised their bottom, and the sudden freshets of the 

 spring annually carry down additional quantities into the plain. The 

 elevated portions of the district thus raised, and which are often of 

 considerable extent, can either not at all, or only with great difficulty, 

 be reached by means of canals from the low river-beds of the neigh- 

 bouring valleys. They have assumed the character of steppes, and 

 now only produce heather and saline plants. By means of Artesian 

 wells, these and similar districts, now neglected only for want of water, 

 might easily be brought into a state of cultivation. 



Within the central region of the great volcanic range, respecting 

 which only a few considerations bearing on the general question have 

 been above alluded to, are to be found the greatest heights of the Lower 

 Caucasus. There we have, as an isolated and independent system, 

 the imposing and extensive mountain of Alaghez, the base of which 

 is 1 70 wersts m circumference ; it is a phsenomenon as peculiar as it 

 is remarkable, in which the laws of craters of elevation are most 

 fully borne out, and affords an amount of facts of the greatest 

 importance for the doctrine of mountain chains. The uplands which 

 exist on the summit of the flat dome of Alaghez have, from a number 

 of measurements from the best points, a mean elevation of 99/0 French 

 feet above the sea. Four pyramidal rocky points are placed with great 

 regularity round the highest base of the excentrical Caldera^^. The 

 highest of them has, according to Fedorow's trigonometrical measure- 

 ments, an absolute height of 12,886 French feet; and the lowest, 

 towards the S.W., is by my barometrical measurements 866 French 

 feet lower. The conditions of climate round the mountain are very 

 different, '^^^leat scarcely ripens on the upland of Goeseldaraf, at 

 the north foot of Alaghez, 6343 French feet above the sea ; whilst at 



* The point where the maximum of elevating power was exerted, causing the 

 separation of the edges of the Caldera, is stated by the author in a long explana- 

 tory note, not to correspond with the central axis in the real summit of the whole 

 dome, but to lie seven wersts to the north-east from the summit. 



t Ghieuzel-dereh, Fair Valley. 



