Geological Work in Old Age 379 



elucidation of many of the difficulties that presented themselves. 

 I well remember a visit which I paid to Down at this period. At the 

 side of the little study stood flower-pots containing earth with worms, 

 and, without interrupting our conversation, Darwin would from time 

 to time lift the glass plate covering a pot to watch what was going 

 on. Occasionally, with a humourous smile, he would murmur some- 

 thing about a book in another room, and slip away; returning 

 shortly, without the book but with unmistakeable signs of having 

 visited the snuff-jar outside. After working about a year at the 

 worms, he was able at the end of 1881 to publish the charming little 

 book The Formation of Vegetable Mould through the Action of 

 Worms, with Observations on their Habits. This was the last of his 

 books, and its reception by reviewers and the public alike afforded 

 the patient old worker no little gratification. Darwin's scientific 

 career, which had begun with geological research, most appropriately 

 ended with a return to it. 



It has been impossible to sketch the origin and influence of 

 Darwin's geological work without, at almost every step, referring to 

 the part played by Lyell and the Principles of Geology. Haeckel, 

 in the chapters on Lyell and Darwin in his History of Creation, and 

 Huxley in his striking essay On the Reception of the Origin of 

 Species 1 have both strongly insisted on the fact that the Origin of 

 Darwin was a necessary corollary to the Principles of Lyell. 



It is true that, in an earlier essay, Huxley had spoken of the 

 doctrine of Uniformitarianism as being, in a certain sense, opposed 

 to that of Evolution 2 ; but in his later years he took up a very 

 different and more logical position, and maintained that " Consistent 

 Uniformitarianism postulates evolution as much in the organic as in 

 the inorganic world. The origin of a new species by other than 

 ordinary agencies would be a vastly greater ' catastrophe ' than any 

 of those which Lyell successfully eliminated from sober geological 

 speculation 3 ." 



Huxley's admiration for the Principles of Geology, and his con- 

 viction of the greatness of the revolution of thought brought about 

 by Lyell, was almost as marked as in the case of Darwin himself 4 . He 

 felt, however, as many others have done, that in one respect the 

 very success of Lyell's masterpiece has been the reason why its 

 originality and influence have not been so fully recognised as they 

 deserved to be. Written as the book was before its author had 



1 L. L. ii. pp. 179204. 



2 Huxley's Address to the Geological Society, 1869. Collected Essays, Vol. vin. p. 305, 

 London, 1896. 



3 L. L. n. p. 190. 



4 See his Essay on "Science and Pseudo Science." Collected Essays, Vol. v. p. 90, 

 London, 1902. 



