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the interior large masses of molten matter, which distributed by water would 
become stratified rocks of varied thickness and of distinctive character. 
The former action is exhibited during the Tertiary period by the upheaval 
of the Alps, Apennines, Carpathian and Himalayan ranges, and the latter opera- 
tion is exemplified by the formation of newer Pliocene beds of Italy and Sicily. 
Respecting these Lyell says, — 
“ There is probably no part of Europe where the newer Pliocene formations 
enter so largely into the structure of the earth’s crust, or rise to such heights 
above the level of the sea, as Sicily. They cover nearly one half the island, 
and near its centre, Castogiovanni, reach an elevation of 3,000 feet.” 
The beds are regularly horizontal and several hundred feet in thickness, the 
limestone passes downwards into sandstone and conglomerate, below which 
are clay and blue marl. These are most interesting stratified beds, formed un- 
doubtedly from materials disgorged by volcanic action from the interior of the 
earth. , 
During the deposition of these beds there is undoubted evidence that the 
Glacial period had commenced, and that the glaciation at the Pole was steadily 
extending. 
Now what does this glaciation mean ? Simply this, that the crust of the 
earth no longer transmitted heat sufficient to melt the snow that fell upon it ; 
that at that period there was no diversion, as now, of vast volumes of tidal 
waters of high temperature from the Equator to the Pole, and that there was a 
gradual but steady accumulation of snow and ice in the polar regions. This 
accumulation implies a corresponding evaporation and abstraction of water 
from the equatorial regions. The result would be a simultaneous loading of 
the crust at the Pole, and diminution of pressure on the parts previously covered 
by the sea. The natural consequence would be a squeezing-out of molten 
matter from the interior as above referred to, and probably the simultaneous 
crushing of the crust and formation of mountains, or further elevation of those 
previously raised. 
Such results would, however, in no way arrest the process of snow-accumu- 
lation at the Pole ; the higher the mass of snow became, the greater tendency 
would there be to extract every particle of moisture from the atmosphere, and 
it is difficult to conceive a limit to the process until the ocean should be dried 
up and all the water be collected in a frozen condition at the Pole. 
I have as yet based my argument solely upon the admitted freedom of the 
earth’s crust to move vertically. I must now suggest the probability (as I 
have already more fully explained in a paper presented to the Institute) of 
the crust of the earth being free to move horizontally on the internal mass of 
matter, as well as vertically, and that, when its equilibrium was destroyed by 
the combined accumulation of snow at the Poles and abstraction of weight 
unequally from the surface towards the Equator, the crust of the earth did shift 
its position as already suggested — reeling to and fro — by which some of the 
ice was thawed ; it steadied again, but eventually so far shifted its position as 
to launch the burden of accumulated frozen materials towards the Equator, 
