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tions of the Imperial School of Mines, that it is now furnished with 
many illustrations of the sedimentary deposits of the empire, even 
from the remotest parts of the Altai and the countries bordering om 
China. It will be my duty and pleasure very shortly to bring before ~ 
your notice the names of many officers of the Russian corps of Mines, ~ 
whose labours were of material use to myself and associates in our 
distant explorations ; but I cannot resist naming at once Colonel Hel- 
mersen, the inspector of the establishment, who whether he be viewed 
as a physical geographer, a geologist, or as a writer, has rendered most 
valuable service to Russia by his luminous and attractive descriptions 
of the structure and outline of various parts of the empire, including 
the most remote tracts. I beg also to refer you to the five published 
volumes of the School of Mines, as works containing much excellent 
matter, and highly creditable both to the government which pro- 
moted their publication, and to the officers whose memoirs they con- 
tain. 
In the mean time, besides what is doing on the Neva, a periodical 
work on Russia has appeared at Berlin under the title of ‘ Archiv fiir 
Wissentschaftliche Kiinde von Russland,’ by the enterprising travel- 
ler A. Erman, of which two parts are published. Together with va- 
rious memoirs on physical geography, history, language, antiquities, 
and physics, the editor has added a sketch of the recent advances in 
the geology of Russia, and illustrates his views by the publication of 
a small outline map of the empire. In the estimate of the geological 
steps in Russia which various labourers have accomplished, I rejoice 
to see the name of our countryman Strangways placed where it ought 
to be, as the first who applied the methods of modern practical geo- 
logy to that empire, by the publication of his general map in the year 
1822. Nevertheless it is too certain, as M. de Verneuil and myself 
informed you last year, that when we first visited St. Petersburgh in 
1840, this map, though published in our Transactions, was, as far as we 
could ascertain, unknown to the men of science in that country. In 
the first memoir on Russia, we specially directed your attention to the 
merits of Strangways, and we shall have ample opportunities here- 
after of reverting to them. What I have now to observe in reference 
to the map of M. A. Erman is, that in his account of it, the special 
researches and the new points which my friend M. de Verneuil and 
myself established, are merged with what I must consider the copies 
of our views. The source whence the chief materials were ob- 
tained, is sufficiently proved indeed by the words “ Silurische und 
Devonische schichten” engraved upon the map, particularly when 
coupled with the fact, that M. de Verneuil, Count Keyserling, and 
myself are the only geologists who traced the older groups to the 
White Sea, aided materially, as we have previously acknowledged, in 
a part of that region, by the Baron A. de Meyendorf, and for a short 
time by Professor Blasius. The original observations which we made 
were inserted by myself on a map which was shown at Moscow and 
St. Petersburgh in August, and to the British Association at Glasgow, 
in September 1840. On this map the range of the great bands of 
Silurian, Devonian, and Carboniferous rocks from St. Petersburgh 
