ciples of Geology_ had not been written, we should never have had
the _Origin of Species_, I think I should not be going too far: at all
events, I can safely assert, from several conversations I had with
Darwin, that he would have most unhesitatingly agreed in that opinion.

Darwin's devotion to his 'dear master' as he used to call Lyell, was of
the most touching character, and it was prominently manifested in all
his geological conversations. In his books and in his letters he never
failed to express his deep indebtedness to his 'own true love' as he
called the _Principles of Geology_. In what was Darwin's own most
favourite work, the _Narrative of the Voyage of the Beagle_, he wrote
'To Charles Lyell, Esq., F.R.S., this second edition is dedicated with
grateful pleasure, as an acknowledgment that the chief part of whatever
scientific merit this Journal and the other works of the author may
possess, has been derived from studying the well-known, admirable
_Principles of Geology_.'

How Lyell's first volume inspired Darwin with his passion for geological
research, and how his second volume was one of the determining causes in
turning his mind in the direction of Evolution, we shall see in the
sequel. In 1844, Darwin wrote to Leonard Horner how 'forcibly impressed
I am with the infinite superiority of the Lyellian School of Geology
over the continental,' he even says, 'I always feel as if my books came
half out of Lyell's brain'; adding 'I have always thought that the great
merit of the _Principles_ was that it altered the whole tone of one's
mind, and therefore that, when seeing a thing never seen by Lyell one
yet saw it partially through his eyes[66].' About the same time Darwin
wrote, 'I am much pleased to hear of the call for a new edition of the
_Principles_: what glorious good that work has done[67]!' And in the
_Origin of Species_ he gives his deliberate verdict on the book,
referring to it as 'Lyell's grand work on the _Principles of Geology_,
which the future historian will recognise as having produced a
revolution in Natural Science[68].'

Darwin seemed always afraid, such was his sensitive and generous nature,
that he did not sufficiently acknowledge his indebtedness to Lyell. He
wrote to his friend in 1845:

'I have long wished not so much for your sake as for my own
feelings of honesty, to acknowledge more plainly than by mere
reference, how much I geologically owe you. Those authors,
how