PHYSICAL PROOFS OF THE FORMER ABODE OF AN INLAND SEA. 317 
posed of palaeozoic rocks rising gently into the Obschey Sirt, and forming the 
southern limb of the great Permian basin. The western coast is most decisively 
marked by the high grounds and promontories constituting the right bank of 
the Volga, which consisting, as we have shown, of Jurassic and cretaceous strata, 
rising several hundred feet above the stream, decline near Kamischine, under the 
tertiary strata. The latter ranging by Tzaritzin to Sarepta, occupy the left bank 
of the Sarpa, and there form the coast of a former Caspian (see Map), amid the 
desiccated and incoherent beds of which the Volga now finds its way to Astra- 
khan. No one, in truth, can have stood upon the promontories of the Volga and 
the Sarpa, and have observed their salient and re-entering angles, so like the worn 
coasts of the sea, nor have gazed, as we have done, over the vast expanse of lower 
steppe at his feet, covered with marine exuviae, some of them identical with forms 
now living in the Caspian, and others closely allied to them, without being con- 
vinced, that there was a period, — and at no very distant time in the history of the 
planet, — when the waves of a former Caspian washed against these shores. 
This, indeed, was the idea of our precursor Pallas, though he did not attempt, 
as we do, to refer this desiccation to epochs anterior to the historical jera. In 
illustrating his view, we must also say, that Pallas has made use of one argument 
which seems to be irrelevant. Observing towards the summit of the escarpment 
on the Sarpa near Sarepta, irregular concretions of agglutinated sand, which did 
not penetrate far into the body of the soft sandstone, he imagined them to be the 
remaining evidences of a peculiar action of the sea (by which such forms are occa- 
sionally produced), when it stood at between 300 and 400 feet above the present 
level. As, however, we have repeatedly found similar, shoi’t and irregular sandy 
concretions in the tertiary sandstones of the South of Russia, to which, indeed, 
we have alluded — often far removed from any coast line — and as we could when 
on the spot discover no difference between them and the examples in the cliffs 
of the Sarpa which Pallas cites, we cannot admit that such configuration has any 
reference whatever to the action of a former Caspian. 
We shall now adduce other evidence derived from Mount Bogdo, and to which 
Pallas has also partially adverted, which in itself is a convincing proof, either of a 
former higher level of the Caspian, or of the elevation of the ancient cliffs of that 
great inland sea. In the Little Bogdo the sands with Caspian shells rise up in 
slopes, and so obscure the hill, that we may suppose it formed a shoal in the former 
sea. In the Great Bogdo, however, the same sand and shells reach only a certain 
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