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, however, who like you educate people's minds as well as teach them special facts, can never, I should think, have full justice done them except by posterity, for the mind thus insensibly improved can hardly perceive its own upward ascent.' Very heartily, as I can bear witness from long intercourse with him, was this deep affection of Darwin reciprocated by the man who was addressed by him in his letters as 'Your affectionate pupil.' But a stranger who conversed with Lyell would have thought that he was the junior and a disciple; so profound was his reverence for the genius of Darwin.