530 Geological Society: Anniversary Address, 1843. 
practical mining engineer; they give at one view the direction, in- 
clination, thickness and quality of the coals at each locality, also 
the characters of the associated strata, as well as the state of the 
works, and their produce at each mine or trial-spot. To these is 
added another set of tables, in which the chemical analysis of the 
coals from forty-three different places is given by M. Malivaud, 
another agent of M. Demidoff. 
Into such details, valuable as they are, it was not our province to 
enter, and I will now, therefore, merely offer a few remarks explana- 
tory of those points in which the geological conclusions of my friends 
and self either agree or are at variance with those of M. Le Play. 
Certain fossils which he had brought to France, and which we 
inspected before our journeys to Russia (1840), first led us to be- 
lieve, that these coal beds are subordinate to the carboniferous 
limestone. Of this, indeed, there could be no doubt, for the species 
were, to a great extent, the very same as those with which we 
were familiar in rocks of that age in western Europe. On in- 
terrogating M. Le Play, however, we could not ascertain that he 
had arrived at any defined idea of a succession of strata, derived 
either from the stratigraphical order of mineral masses, or from their 
imbedded organic remains. In fact, he then distinctly acquainted 
us with what has now appeared in his work, that, owing to the dis- 
turbed and convoluted condition of the strata, the want of persist- 
ency of mineral characters, and the apparent existence of similar 
species of shells throughout the series, it was impracticable to-as- 
sign a base line to the deposits, or to trace their uppermost limits, 
still less a passage into any superior formations, 
Now, as we have ventured to effect these objects, with what sue- 
cess we must leave others to decide, I will here briefly state why 
I conceive M. Le Play did not arrive at similar results; although 
he had in his own hands some means of proof, which, through 
the short time at our disposal, we never obtained. 
No geologist, however practised, can, I venture to say, explain 
the structure of any complicated part of a distant country, unless 
he has made himself master of the clear succession of its normal 
formations. Long as I have been occupied in the study of the Palaeo- 
zoic rocks, I am confident that, had my friends and myself been 
thrown suddenly into the chain of the Donetz, and had been desired 
at once to unravel its complexity, we should have reached no other 
geological result than that to which M. Le Play has attained, viz. of 
stating that the coal-seams are, as a whole, subordinate to the car- 
boniferous or mountain limestone. We had, however, by two years 
of extensive comparative researches, obtained an intimate acquaint- 
ance, not only with the older Paleozoic rocks of Russia generally, 
but, in reference to the carboniferous system, had convinced our- 
selves, that, throughout the enormous area over which we had traced 
it, the upper or coal group of western Europe was absent; and that 
the calcareous or lower group, occupying the whole carboniferous 
horizon, was divisible into three stages, by help of certain fossils 
characteristic of each. Again, we had ascertained, by numerous 
