gs perfectly different; on the one hand original mountains
formed by nature, but we know not how, endued with solidity, but not
differing in this respect from those of a posterior formation; on the
other hand, secondary mountains, formed by the collection of materials
in the sea, therefore, not having solidity as a quality inherent in
their constitution, but only occasional or accidental in their nature.
If, therefore, it be the natural constitution of things upon the surface
of this earth to indurate and become solid, however originally formed
loose and incoherent, we should thus find an explanation of the
consolidation of those masses which had been lately formed of the loose
materials of the ocean; if, on the contrary, we find those pretended
primitive mountains, those bodies which are endued with hardness
and solidity, wasting by the hand of time, and thus wearing in the
operations natural to the surface of the earth, Where shall we find
the consolidating operations, those by which beds of shells have been
transformed into perfect marble, and siliceous bodies into solid flint?
or how reconcile those opposite intentions in the same cause?

Nothing can be more absurd than to suppose a collection of shells and
corals, amassed about the primitive mountains of the earth, to become
mountains equally solid with the others, upon the removal of the sea; it
would be inconsistent with every principle of sound reasoning to suppose
those masses of loose materials to oppose equal resistance to the
wasting and destroying operations of the surface of the earth, as do
those pretended primitive masses, which might be supposed endued with
natural hardness and solidity; yet, consult the matter of fact, and it
does not appear that there is any difference to be perceived. There are
lofty mountains to be found both of the one kind and the other; both
those different masses yield to the wasting operations of the surface;
and they are both carried away with the descending waters of the earth.

It is not here meant to affirm, that a mass of marble, which is
a calcareous substance, opposes equal resistance, whether to the
operations of dissolution or attrition, as a mass composed of granite or
of quartz; it is only here maintained that there are in the Alps lofty
mountains of marble, as there are in other places lower masses of
granite and its accompanying schistus. But that which is particularly to
be attended to here is this: In all countri