devoted to a consideration of the connection between the facts
previously stated and Darwin's theory of the origin of species by
variation and natural selection. The keynote of Lyell's work,
throughout his life, was observation. Lyell was no cabinet
geologist; he went to nature and studied phenomena at first hand.
Possessed of abundant leisure and ample means he travelled far and
wide, patiently collecting material and building up the modern
science of physical geology, whose foundations had been laid by
Hutton and Playfair. From the facts thus collected he drew his
inferences, and if later researches showed these inferences to be
wrong, unlike some of his contemporaries, he never hesitated to say
so. Thus and thus only is true progress in science attained.

Lyell is universally recognised as the leader of the Uniformitarian
school of geologists, and it will be well to consider briefly what
is implied in this term. The principles of Uniformitarianism may be
summed up thus: THE PRESENT IS THE KEY TO THE PAST. That is to say,
the processes which have gone on in the past were the same in
general character as those now seen in operation, though probably
differing in degree. This theory is in direct opposition to the
ideas of the CATASTROPHIC school, which were dominant at the
beginning of the nineteenth century. The catastrophists attributed
all past changes to sudden and violent convulsions of nature, by
which all living beings were destroyed, to be replaced by a fresh
creation. At least such were the tenets of the extremists. In
opposition to these views the school of Hutton and Lyell introduced
the principle of continuity and development. There is no
discrepancy between Uniformitarianism and evolution. The idea of
Uniformitarianism does not imply that things have always been the
same; only that they were similar, and between these two terms