My dear Darwin,—

I must write a word before starting to-morrow morning for Paris, to thank you for your last letter, and to say what a privilege I feel it to be allowed to read your sheets in advance.¹ They go far beyond my anticipations, both as to the quantity of original observation, and the materials brought together from such a variety of sources, and the bearing of which the readers of the ‘Origin’ will now comprehend in a manner they would not have done had this book come out first.² The illustrations of the pigeons are beautiful, and most wonderful and telling for you, and the comparison of the groups with natural families difficult to divide will be most persuasive to real naturalists. The rabbits are famously worked out, osteology and all.³ The reason I have not got on faster is, that I have been correcting the press of my recast of Mount Etna, which I have reviewed twice since my former edition of fourteen years ago,⁴ also the Santorin eruption of 1866, and my grand New Zealand earthquake, which produced more permanent change than any other yet known.⁵ I have also had to rewrite my chapters on the ‘Causes of Volcanic Heat,’ the ‘Interior of the Earth,’ &c.⁶ But all this is in the printers’ hands, and I can now give myself to variation and selection.

Believe me, my dear Darwin, ever affectionately yours, | Charles Lyell.