e earth to be at rest, until the astronomer taught that it
was carried through space with inconceivable rapidity. In like manner
was the surface of this planet regarded as having remained unaltered
since its creation, until the geologist proved that it had been the
theatre of reiterated change, and was still the subject of slow but
never-ending fluctuations. The discovery of other systems in the
boundless regions of space was the triumph of astronomy; to trace the
same system through various transformations--to behold it at successive
eras adorned with different hills and valleys, lakes and seas, and
peopled with new inhabitants, was the delightful meed of geological
research. By the geometer were measured the regions of space, and the
relative distances of the heavenly bodies;--by the geologist myriads of
ages were reckoned, not by arithmetical computation, but by a train of
physical events--a succession of phenomena in the animate and inanimate
worlds--signs which convey to our minds more definite ideas than figures
can do of the immensity of time.

Whether our investigation of the earth's history and structure will
eventually be productive of as great practical benefits to mankind as a
knowledge of the distant heavens, must remain for the decision of
posterity. It was not till astronomy had been enriched by the
observations of many centuries, and had made its way against popular
prejudices to the establishment of a sound theory, that its application
to the useful arts was most conspicuous. The cultivation of geology
began at a later period; and in every step which it has hitherto made
towards sound theoretical principles, it had to contend against more
violent prepossessions. The practical advantages already derived from it
have not been inconsiderable; but our generalizations are yet imperfect,
and they who come after us may be expected to reap the most valuable
fruits of our labor. Meanwhile, the charm of first discovery is our own;
and, as we explore this magnificent field of inquiry, the sentiment of a
great historian of our times may continually be present to our minds,
that "he who calls what has vanished back again into being, enjoys a
bliss like that of creating."[122]

CHAPTER V.

PREJUDICES WHICH HAVE RETARDED THE PROGRESS OF GEOLOGY

Prepossessions in regard to the duration of past time--Prejudices
arising from our peculiar position as inhabitants of the land--Of
those occasioned by o