376 Darwin and Geology 
able to grapple with the immense pile of MS. notes which he had 
accumulated on the species question. The first sketch of 35 pages 
(1842), had been enlarged in 1844 into one of 230 pages’; but in 
1856 was commenced the work (never to be completed) which was 
designed on a scale three or four times more extensive than that 
on which the Origin of Species was in the end written. 
In drawing up those two masterly chapters of the Origin, “On 
the Imperfection of the Geological Record,” and “On the Geological 
Succession of Organic Beings,’ Darwin had need of all the ex- 
perience and knowledge he had been gathering during thirty years, 
the first half of which had been almost wholly devoted to geological 
study. The most enlightened geologists of the day found much that 
was new, and still more that was startling from the manner of its 
presentation, in these wonderful essays. Of Darwin’s own sense of the 
importance of the geological evidence in any presentation of his 
theory a striking proof will be found in a passage of the touching 
letter to his wife, enjoining the publication of his sketch of 1844. 
“In case of my sudden death,” he wrote, “...the editor must be a 
geologist as well as a naturalist”.” 
In spite of the numerous and valuable palaeontological discoveries 
made since the publication of The Origin of Species, the importance 
of the first of these two geological chapters is as great as ever. It 
still remains true that “Those who believe that the geological record 
is in any degree perfect, will at once reject the theory ’—as indeed 
they must reject any theory of evolution. The striking passage with 
which Darwin concludes this chapter—in which he compares the 
record of the rocks to the much mutilated volumes of a human 
history—remains as apt an illustration as it did when first written. 
And the second geological chapter, on the Succession of Organic 
Beings—though it has been strengthened in a thousand ways, by the 
discoveries concerning the pedigrees of the horse, the elephant and 
many other aberrant types, though new light has been thrown even 
on the origin of great groups like the mammals, and the gymnosperms, 
though not a few fresh links have been discovered in the chains of 
evidence, concerning the order of appearance of new forms of life 
—we would not wish to have re-written. Only the same line of 
argument could be adopted, though with innumerable fresh illus- 
trations. Those who reject the reasonings of this chapter, neither 
would they be persuaded if a long and complete succession of 
“ancestral forms” could rise from the dead and pass in procession 
before them. 
1 [The first draft of the Origin is being prepared for Press by Mr Francis Darwin 
and will be published by the Cambridge University Press this year (1909). A.C. 8.] 
2 L. L. a. pp. 16, 17. 
