588 
CONCLUSION. 
the sedimentary deposits in the Caucasian chain, without explaining them in the 
same way as those of Russia and the Ural ? Yet, however analogous, the pheno- 
mena of the Caucasian chain, as just expressed, are very different in age from 
those of the north or the Ural Mountains. And as the eruptions, by which 
enormous masses of sedimentary and plutonic matter were heaved up to great 
heights, took place after the consolidation of the chalk ; might not, we ask, the 
raising up of so much solid matter have led to a great corresponding depression in 
an adjacent portion of the earth’s surface? May not, in short, some of the first 
upheavals of the mighty Caucasus have been the means of separating a wide tract 
horn the ancient ocean, and of occasioning at the same time that vast depression 
in which the Aralo-Caspian beds were accumulated ? 
Rut if we thus hypothetically attempt to shadow out the cause of one of the manv 
great changes which have taken place, it should be remembered, that, with the 
exception of such passing allusions (including our speculations upon the transport 
of erratic superficial materials and the accumulation of the black earth), nothing 
involving the true history and classification of the successive formations of the 
earth’s crust, — nothing, in short, affecting the great truths of inductive geology, — 
has been advanced, which is not substantiated by ample proofs. 
In Russia and Scandinavia, the first pages of true geological history are, we have 
said, more clearly, legibly and largely defined than in any other region with which 
we are acquainted ; and, in conclusion, we now refer our readers to our second 
volume, which consisting of a detailed description of the fossil remains in each 
rock system, constitutes the chief justification of those leading inductions, by the 
accuracy of which we are desirous of being judged. 
It would, indeed, be presumptuous did we pretend, that this work could be re- 
garded as a full and accurate monograph of the structural relations of the vast 
empire of Russia. But although years must elapse before such a consummation 
be attained, we offer this outline to the public, in the hope that those who from 
their knowledge of the subject will be best aware of its imperfections, may approve 
of the efforts we have made, to lay down and render permanent some additional 
foundation-stones of geological science. 
Finally, may we not say, that every effort made by man to read new lessons in 
the ancient book of nature has augmented his admiration of the works of the 
1 In North America they are equally well defined. (See Introduction, Chapter I.) 
