th's history which can best be compared
with the present state of things, and more thoroughly investigated than
any other, leads to the conclusion that the extinction and creation of
species, has been and is the result of a slow and gradual change in the
organic world.

UNIFORMITY OF CHANGE CONSIDERED, SECONDLY, IN REFERENCE TO SUBTERRANEAN
MOVEMENTS.

To pass on to another of the three topics before proposed for
discussion, the reader will find, in the account given in the second
book of the earthquakes recorded in history, that certain countries
have, from time immemorial, been rudely shaken again and again, while
others, comprising by far the largest part of the globe, have remained
to all appearance motionless. In the regions of convulsion rocks have
been rent asunder, the surface has been forced up into ridges, chasms
have opened, or the ground throughout large spaces has been permanently
lifted up above or let down below its former level. In the regions of
tranquillity some areas have remained at rest, but others have been
ascertained by a comparison of measurements, made at different periods,
to have risen by an insensible motion, as in Sweden, or to have subsided
very slowly, as in Greenland. That these same movements, whether
ascending or descending, have continued for ages in the same direction
has been established by geological evidence. Thus, we find both on the
east and west coast of Sweden, that ground which formerly constituted
the bottom of the Baltic and of the ocean has been lifted up to an
elevation of several hundred feet above high-water mark. The rise within
the historical period has not amounted to many yards, but the greater
extent of antecedent upheaval is proved by the occurrence in inland
spots, several hundred feet high, of deposits filled with fossil shells
of species now living either in the ocean or the Baltic.

To detect proofs of slow and gradual subsidence must in general be more
difficult; but the theory which accounts for the form of circular coral
reefs and lagoon islands, and which will be explained in the last
chapter of the third book, will satisfy the reader that there are spaces
on the globe, several thousand miles in circumference, throughout which
the downward movement has predominated for ages, and yet the land has
never, in a single instance, gone down suddenly for several hundred feet
at once. Yet geology demonstrates that the persistency of subterranean
movements in o