ABICh's geological sketches beyond the CAUCASUS. 47 



Arzian and Pozchowdagh with their flat conical forms, are the most 

 remarkable, 



A straight line connecting the summits of the two Ararats runs 

 parallel with the above-mentioned line, deviating 58° W. from the 

 meridian. Prolonged in the opposite direction (viz. S.E.), it strikes 

 the isolated rock pyramids of the Takjaltu near Kulpi, and of the 

 Yelanlidagh (Snake Mountain) near Nachitschewan. These two 

 formations are mineralogically the same, and with a remarkable simi- 

 larity of appearance, stand in an equally important geological relation 

 to the great masses of rock-salt which are found in the mottled clays 

 at both extremities of the valley of the Araxes. At a distance of 150 

 wersts N.W. from Mount Ararat, the above-mentioned line touches 

 the summit of the Saganlu-dagh, the wooded volcanic mountain mass 

 overlooking the plain of Kars * . 



If in the same way we draw a line from the summit of the Kasbek 

 at an angle of 66° 30' W. of the meridian, it will at a distance of 176 

 wersts N.W. cut the summit of Elburuz, and to theS.E. at a distance 

 of 196 wersts, the Djultidag rising on the ridge of the Dagestan 

 mountains above the limit of perpetual snow. This line however 

 must be looked upon as representing the entire length of the whole 

 Lower Caucasus. 



The above-mentioned relations and connexions in the relative posi- 

 tion of the principal summits of the mountain district of the Caucasus 

 are not merely accidental ; they are important facts, which must be 

 considered as the result of those internal laws which were alluded to 

 at the commencement of this notice. 



It was well known that volcanic forces had contributed to the ele- 

 vation of the Caucasus in the same way as had been the case with 

 regard to the Andes of South America ; but the extraordinary share 

 which volcanic action had exerted in modifying the surface of the 

 mountain districts in the Southern Caucasus was neither known, nor 

 even suspected. The geological period when these remarkable effects 

 took place is, relatively speaking, very modern ; its last appearances 

 are clearly visible in the early dawn of the history of the human race. 

 Throughout the whole extension of the Araxes plain up to the high 

 plains of Schuragel and Kars, the upper sedimentary bed is a loose 

 calcareous tuff, which is filled with the well-preserved shells of the 

 same species of Mytilus which still inhabits the Caspian Seaf. This 

 calcareous tuff is immediately covered by the lavas and other volcanic 

 products which extend from the volcanic uplands to the plains, which 

 are now respectively at the heights of 2400 and 4500 French feet 

 above the level of the ocean. 



Most remarkable is the difference of the results which elevating 

 volcanic forces, and particularly eruptive volcanic action, which is still 

 continuing, although with diminished intensity, on our planet, have 

 produced in the development of the forms of the Upper and Lower 

 Caucasus. In the former district they raised, by a great effort of 



* See Hamilton's Asia Minor, vol. i. p. 189. 

 t Ibid. vol. i. pp. 186 and 203. 



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