being the manner of the formation of the crust of the world, can we
form any judgment of its duration and durability? If we could measure
the rate of the attrition of the present continents, we might estimate
the duration of the older continents whose attrition supplied the
material for the present dry land. But as we cannot measure the
wearing-away of the land, we can merely state generally, first, that the
present dry land required an indefinitely long period for its formation;
second, that the previous dry land which supplied material for its
formation required equal time to make; third, that there is at present
land forming at the bottom of the sea which in time will appear above
the surface; fourth, that we find no vestige of a beginning, or of an
end.

Granite has in its own nature no claim to originality, for it is found
to vary greatly in its composition. But, further, it is certain that
granite, or a species of the same kind of stone, is found stratified. It
is the _granit feuilletee_ of M. de Sauffure, and, if I mistake not, is
called _gneiss_ by the Germans. Granite being thus found stratified, the
masses of this stone cannot be allowed to any right of priority over the
schistus, its companion in Alpine countries.

Lack of stratification, then, cannot be considered a proof of primitive
rock. Nor can lack of organized bodies, such as shells, in these rocks,
be considered a proof; for the traces of organized bodies may be
obliterated by the many subsequent operations of the mineral region. In
any case, signs of organized bodies are sometimes found in "primitive"
mountains.

Nor can metallic veins, found plentifully in "primitive" mountains,
prove anything, for mineral veins are found in various strata.

We maintain that _all_ the land was produced from fused substances
elevated from the bottom of the sea. But we do not hold that all parts
of the earth have undergone exactly similar and simultaneous
vicissitudes; and in respect to the changes which various parts of the
land have undergone we may distinguish between primary and secondary
strata. Nothing is more certain than that there have been several
repeated operations of the mineralising power exerted upon the strata in
particular places, and all those mineral operations tend to
consolidation. It is quite possible that "primitive" masses which differ
from the ordinary strata of the globe have been twice subjected to
mineral operations, having been first