LOW STEPPE OF THE CAUCASUS. 
319 
Whilst considering this phenomenon it is worthy of remark, that the erosion is on 
the eastern face of the hill ; since from all we can learn this is still the point from 
which the most violent winds of these regions still proceed — the great land winds, 
in fact, of continental Asia. If not mistaken, we could adduce examples of inden- 
tations in sandstone, nearly similar to those of Mount Bogdo, made by the present 
sea upon the British cliffs ; and for ancient analogies we would refer to the deep 
cylindrical erosions of the surface of the chalk so common all over Western Europe. 
Whilst then we have indisputable proofs, from the general configuration of the 
masses of land which flank this lower steppe, that the bottom of a former Caspian 
was raised, the lines of water- worn holes in the vertical face of Mount Bogdo (evi- 
dently from its composition an islet in this former sea) are striking confirmations 
of the view, that such elevations were effected during two periods. 
Low Steppe of the Caucasus . — We wish it were in our power to give some 
sketch, from personal observation, of the southern extension of the tract above 
described into the low steppe of the Kalmucks, which constitutes, in fact, its 
southern prolongation, and spreads over a large portion of the region between the 
Black and Caspian Seas. Although, however, we only trended a portion of its 
northern shore along the Sea of Azof, we know enough of it from Pallas and our 
precursors, as well as from Strangways, Eichwald and Hommaire, to feel certain, 
that to a great extent it is of the same composition, and contains the same 
shells as the steppe we have described, and of which, indeed, it is the continua- 
tion. In some parts, the low Caucasian steppe, particularly along the course of 
the Kuma and for some distance from the Caspian, is more argillaceous than 
the larger portion of the Kirghis steppe ; resembling rather the deposits at Tchorno- 
yar. It is further remarkable in containing so much salt disseminated in the 
earth, that after the wet seasons, the water having evaporated, the desiccated 
surface throws off coats or efflorescences of muriate of soda. In reference to 
this phenomenon, we must draw a distinction between the saline productions 
of the steppe north of Astrakhan and those of the lower steppe of the Caucasus. 
The former (as we have already seen, p. 196) are the products of subjacent and 
very ancient rocks (Permian, &c.), whose included masses of rock-salt give off 
perennial and copious springs, which, issuing through the ovei lying sandy beds 
of the desiccated Caspian, form highly saline pools and lakes. The latter, on the 
contrary, even where they are most saline (as along the banks of the Kuma), seem 
to be derived from troughs or cavities occupied by marine mud or mire, in which a 
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