576 
CHANGES PRODUCED BY MUD VOLCANOES* 
That some of these elevations occurred within the historic sera, may be inferred 
from the fact, that in the walls of the fortress of Sudac, near Theodosia in the 
Crimsea, we ourselves saw stones procured from coast-cliffs, which contained 
shells of the Cardium edule and Mytilus edulis, now living in the adjacent Black 
Sea, and which we are disposed to think must have been thrown up on the line of 
eruption of the mud volcanoes, and parallel to the axis of the Caucasus (see Map, 
PL VI.) . The opinion we formed upon the spot, that these mud volcanoes have a deep 
seat, and are as directly connected with internal igneous agency as any other geolo- 
gical phenomenon of eruption, is, we think, sustained not only by their extension 
over a tract 200 versts in length (that line of direction being coincident with the 
fires of Baku and other mud eruptions in the Caspian), but, above all, by the occur- 
rence of fragments of limestone and shale (unlike any portions of the surrounding 
strata), which they have ejected with their mud and scorise 1 . These mud volcanoes 
are, therefore, in our estimation, the last remnants of ancient and more intense 
igneous action, by which enormous masses of sedimentary matter have been hurled 
up, in former epochs, to constitute the lofty Caucasus. 
In alluding to these southern tracts of Russia which have been so recently illus- 
trated byM. Dubois de Montpereux, by the French savans employed by M. Demidoff 
and by M. Hominaire de Hell, whose work is not even completed whilst we write, 
we must again render justice to Mr. Strangways, to whose manuscript, read 21 years 
ago before the Geological Society, we have previously alluded 2 . Speculating upon 
the probable former connection of now detached masses of water winch might then 
have formed an eastern Mediterranean, and citing Strabo, and his commentator 
Gosselin, for various descriptions of ancient geographical features, including the 
probable voyage of the Argonauts beyond the Crimsea, which must then have been 
an island, he concludes with the following striking passage 
“ By whatever cause it may have been drained, the low steppe exhibits no dilu- 
vian phenomena, no system of valleys, no sign of a debacle or sudden and violent 
1 See M. de Verneuil, Mem. Soc. Gdol. de Fr., vol. iii. p. 6-10. Strangways also mentions the pre- 
sence of fragments of limestone and shale in the black bituminous mud and red scorise as an indication that 
the seat of the eruptions is deep. (MS., read before the Geological Society of London, anno 1824.) 
* Mr. Strangways further makes a suggestion respecting the desirableness of the very operation which 
has been recently carried out by M. Hommaire de Hell. “ It is much to be regretted (he says in allusion 
to the operations of MM. Parrot and Engelhardt) that they did not make their observations along the 
course of the Manych instead of across the high steppes. The greatest elevation of the low steppe above 
the Sea of Azof is still undetermined.” 
