ear old master' in the words

'The science of Geology is enormously indebted to Lyell--more
so, as I believe, than to any other man who ever lived[73].'

Alfred Russel Wallace is scarcely less emphatic than Charles Darwin
himself in his expression of affection and admiration for Lyell, and his
indebtedness to the _Principles of Geology_.

In his Autobiography, Wallace writes:--

'With Sir Charles I soon felt at home, owing to his refined and
gentle manners, his fund of quiet humour, and his intense love
and extensive knowledge of natural science. His great liberality
of thought and wide general interests were also attractive to
me; and although when he had once arrived at a definite
conclusion, he held by it very tenaciously until a considerable
body of well-ascertained facts could be adduced against it, yet
he was always willing to listen to the arguments of his
opponents, and to give them careful and repeated
consideration[74].'

Of the influence of the _Principles of Geology_ in leading him to
evolution, he wrote:

'Along with Malthus I had read, and been even more deeply
impressed by, Sir Charles Lyell's immortal _Principles of
Geology_; which had taught me that the inorganic world--the
whole surface of the earth, its seas and lands, its mountains
and valleys, its rivers and lakes, and every detail of its
climatic conditions--were and always had been in a continual
state of slow modification. Hence it became obvious that the
forms of life must have become continually adjusted to these
changed conditions in order to survive. The succession of fossil
remains throughout the whole geological series of rocks is the
record of the change; and it became easy to see that the extreme
slowness of these changes was such as to allow ample opportunity
for the continuous automatic adjustment of the organic to the
inorganic world, as well as of each organism to every other
organism in the same area, by the simple processes of "variation
and survival of the fittest." Thus was the fundamental idea of
the "origin of species" logically formulated from the
consideration of a series of well ascertained facts[75].'

Nor were the two men (who, like Aaron and Hur so steadily sustained the
hands of Darwin in his long vigil), behind the two authors of Natural
Selection themselves in their devotion to Lyell. How touc