CHAPTER V.
DOWN—GEOLOGY OF THE VOYAGE—WORK ON CIRRIPEDES (1842–54).
From September 14th, 1842, until his death, Darwin resided at Down, living a very retired life, and almost exclusively engaged in his scientific researches. Although Down is only twenty miles from London, it is three miles from the nearest railway station (Orpington), and is only now for the first time receiving a telegraph office. A home in such a place enabled Darwin to pursue his work without interruption, remaining, at the same time, within easy reach of all the advantages of London. Here, too, he had no difficulty in avoiding social engagements, which always injured his very precarious health, and thus interfered with work; although, at the same time, he could entertain in his own house at such times as he felt able to do so.
In 1844, and again in 1846, he published works on the geology of the voyage of the Beagle; the first on the Volcanic Islands visited, the second on South America. A second edition, in which both were combined in a single work, appeared in 1876. He seemed somewhat disappointed at the small amount of attention they at first attracted, and wrote with much humour to J. M. Herbert:—“I have long discovered that geologists never read each other’s works, and that the only object in writing a book is a proof of earnestness, and that you do not form your opinions without undergoing labour of some kind.” All geologists were, nevertheless, soon agreed in attaching the highest value to these researches.
ON CIRRIPEDES.
From this time forward his work was almost exclusively zoological. The four monographs on the Cirripedia, recent and fossil, occupied eight years—from October, 1846, to October, 1854. The works on the recent forms were published by the Ray Society (1851 and 1854), and those on the fossil forms by the Palæontographical Society (1851 and 1854). These researches grew directly out of his observations on the Beagle, but it is evident that they reached far greater dimensions than he had at first intended. Thus, at the very beginning of the work, he wrote (October, 1846) to Hooker:—
“I am going to begin some papers on the lower marine animals, which will last me some months, perhaps a year, and then I shall begin looking over my ten-year-long accumulation of notes on species and varieties, which, with writing, I dare say will take me five years, and then, when published, I dare say I shall stand infinitely low in the opinion of all sound Naturalists—so this is my prospect for the future.”
Darwin himself, at any rate towards the end of his life, when he wrote his “Autobiography,” doubted “whether this work was worth the consumption of so much time,” although admitting that it was of “considerable value” when he had “to discuss in the ‘Origin of Species’ the principles of a natural classification.” Sir Joseph Hooker remembers that Darwin at an earlier time “recognised three stages in his career as a biologist: the mere collector at Cambridge; the collector and observer in the Beagle and for some years afterwards; and the trained naturalist after, and only after, the Cirripede work” (Letter to F. Darwin).
Professor Huxley considers that just as by Darwin’s practical experience of physical geography, geology, etc., on the Beagle, “he knew of his own knowledge the way in which the raw materials of these branches of science are acquired, and was, therefore, a most competent judge of the speculative strain they would bear,” so his Cirripede work fitted him for his subsequent speculations upon the deepest biological problems. “It was a piece of critical self-discipline, the effect of which manifested itself in everything your father wrote afterwards, and saved him from endless errors of detail” (Letter to F. Darwin, “Life and Letters”). The history of Darwin’s career has often been used as an argument against those who, not having passed through a similar training as regards systematic zoological work, have ventured to concern themselves with the problems of evolution. Professor Meldola has recently treated of this subject in his interesting presidential address to the Entomological Society (1896). He says:—
“It used formerly to be asserted that he only is worthy of attention who has done systematic, i.e. taxonomic, work. I do not know whether this view is still entertained by entomologists; if so, I feel bound to express my dissent. It has been pointed out that the great theorisers have all done such work—that Darwin monographed the Cirripedia, and Huxley the oceanic Hydrozoa, and it has been said that Wallace’s and Bates’s contributions in this field have been their biological salvation. I yield to nobody in my recognition of the value and importance of taxonomic work, but the possibilities of biological investigation have developed to such an extent since Darwin’s time that I do not think this position can any longer be seriously maintained. It must be borne in mind that the illustrious author of the ‘Origin of Species’ had none of the opportunities for systematic training in biology which any student can now avail himself of. To him the monographing of the Cirripedia was, as Huxley states in a communication to Francis Darwin, ‘a piece of critical self-discipline,’ and there can be no reasonable doubt that this value of systematic work will be generally conceded. That this kind of work gives the sole right to speculate at the present time is, however, quite another point.”
Meldola then goes on to argue that the systematic work of those who know nothing of the living state of the species they are describing does not specially fit them for theorising, and he concludes by quoting the following passage from a letter recently received from A. R. Wallace:—