ur not seeing subterranean changes now in
progress--All these causes combine to make the former course of
Nature appear different from the present--Objections to the
doctrine, that causes similar in kind and energy to those now
acting, have produced the former changes of the earth's surface,
considered.

If we reflect on the history of the progress of geology, as explained in
the preceding chapters, we perceive that there have been great
fluctuations of opinion respecting the nature of the causes to which
all former changes of the earth's surface are referable. The first
observers conceived the monuments which the geologist endeavors to
decipher to relate to an original state of the earth, or to a period
when there were causes in activity, distinct, in kind and degree, from
those now constituting the economy of nature. These views were gradually
modified, and some of them entirely abandoned, in proportion as
observations were multiplied, and the signs of former mutations more
skilfully interpreted. Many appearances, which had for a long time been
regarded as indicating mysterious and extraordinary agency, were finally
recognized as the necessary result of the laws now governing the
material world; and the discovery of this unlooked-for conformity has at
length induced some philosophers to infer, that, during the ages
contemplated in geology, there has never been any interruption to the
agency of the same uniform laws of change. The same assemblage of
general causes, they conceive, may have been sufficient to produce, by
their various combinations, the endless diversity of effects, of which
the shell of the earth has preserved the memorials; and, consistently
with these principles, the recurrence of analogous changes is expected
by them in time to come.

Whether we coincide or not in this doctrine, we must admit that the
gradual progress of opinion concerning the succession of phenomena in
very remote eras, resembles, in a singular manner, that which has
accompanied the growing intelligence of every people, in regard to the
economy of nature in their own times. In an early state of advancement,
when a great number of natural appearances are unintelligible, an
eclipse, an earthquake, a flood, or the approach of a comet, with many
other occurrences afterwards found to belong to the regular course of
events, are regarded as prodigies. The same delusion prevails as to
moral phenomena, and many of thes