ages, and during which new strata
were deposited near the shore in some places, while in others the waves
and currents had time to hollow out rocks, undermine cliffs, and throw
up long ranges of shingle. They undoubtedly show that the movement has
not been always uniform or continuous, but they do not establish the
fact of any sudden alterations of level.

When we are once assured of the reality of the gradual rise of a large
region, it enables us to account for many geological appearances
otherwise of very difficult explanation. There are large continental
tracts and high table-lands where the strata are nearly horizontal,
bearing no marks of having been thrown up by violent convulsions, nor by
a series of movements, such as those which occur in the Andes, and cause
the earth to be rent open, and raised or depressed from time to time,
while large masses are engulfed in subterranean cavities. The result of
a series of such earthquakes might be to produce in a great lapse of
ages a country of shattered, inclined, and perhaps vertical strata. But
a movement like that of Scandinavia would cause the bed of the sea, and
all the strata recently formed in it, to be upheaved so gradually, that
it would merely seem as if the ocean had formerly stood at a higher
level, and had slowly and tranquilly sunk down into its present bed.

The fact also of a very gradual and insensible elevation of land may
explain many geological movements of denudation, on a grand scale. If,
for example, instead of the hard granitic rocks of Norway and Sweden, a
large part of the bed of the Atlantic, consisting chiefly of soft
strata, should rise up century after century, at the rate of about half
an inch, or an inch, in a year, how easily might oceanic currents sweep
away the thin film of matter thus brought up annually within the sphere
of aqueous denudation! The tract, when it finally emerged, might present
table-lands and ridges of horizontal strata, with intervening valleys
and vast plains, where originally, and during its period of submergence,
the surface was level and nearly uniform.

These speculations relate to superficial changes; but others must be
continually in progress in the subterranean regions. The foundations of
the country, thus gradually uplifted in Sweden, must be undergoing
important modifications. Whether we ascribe these to the expansion of
solid matter by continually increasing heat, or to the liquefaction of
rock, or to the