"In this work the author embodied all the materials collected by him for the illustration of South American Geology, save some which have been published elsewhere. One of the most important features of the book was the evidence which it brought forward to prove the slow interrupted elevation of the South American Continent during a recent geological period." (Geikie, loc. cit.)Of this book my father wrote to Lyell:--"My volume will be about 240 pages, dreadfully dull, yet much condensed. I think whenever you have time to look through it, you will think the collection of facts on the elevation of the land and on the formation of terraces pretty good."Of his special geological work as a whole, Professor Geikie, while pointing out that it was not "of the same epoch-****** kind as his biological researches," remarks that he "gave a powerful impulse to" the general reception of Lyell's teaching "by the way in which he gathered from all parts of the world facts in its support."WORK OF THE PERIOD 1842 TO 1854.
The work of these years may be roughly divided into a period of geology from 1842 to 1846, and one of zoology from 1846 onwards.
I extract from his diary notices of the time spent on his geological books and on his 'Journal.'
'Volcanic Islands.' Summer of 1842 to January, 1844.
'Geology of South America.' July, 1844, to April, 1845.
Second Edition of 'The Journal,' October, 1845, to October, 1846.
The time between October, 1846, and October, 1854, was practically given up to working at the Cirripedia (Barnacles); the results were published in two volumes by the Ray Society in 1851 and 1854. His volumes on the Fossil Cirripedes were published by the Palaeontographical Society in 1851 and 1854.
Some account of these volumes will be given later.
The minor works may be placed together, independently of subject matter.
"Observations on the Structure, etc., of the genus Sagitta," Ann. Nat.
Hist. xiii., 1844, pages 1-6.
"Brief descriptions of several Terrestrial Planariae, etc.," Ann. Nat.
Hist. xiv., 1844, pages 241-251.
"An Account of the Fine Dust (A sentence occurs in this paper of interest, as showing that the author was alive to the importance of all means of distribution:--"The fact that particles of this size have been brought at least 330 miles from the land is interesting as bearing on the distribution of Cryptogamic plants.") which often Falls on Vessels in the Atlantic Ocean," Geol. Soc. Journ. ii., 1846, pages 26-30.
"On the Geology of the Falkland Islands," Geol. Soc. Journ. ii., 1846, pages 267-274.
"On the Transportal of Erratic Boulders, etc.," Geol. Soc. Journ. iv., 1848, pages 315-323. (An extract from a letter to Lyell, 1847, is of interest in connection with this essay:--"Would you be so good (if you know it) as to put Maclaren's address on the enclosed letter and post it. It is chiefly to enquire in what paper he has described the Boulders on Arthur's Seat. Mr. D. Milne in the last Edinburgh 'New Phil. Journal' [1847], has a long paper on it. He says: 'Some glacialists have ventured to explain the transportation of boulders even in the situation of those now referred to, by imagining that they were transported on ice floes,' etc. He treats this view, and the scratching of rocks by icebergs, as almost absurd...he has finally stirred me up so, that (without you would answer him) I think Iwill send a paper in opposition to the same Journal. I can thus introduce some old remarks of mine, and some new, and will insist on your capital observations in N. America. It is a bore to stop one's work, but he has made me quite wroth.")The article "Geology," in the Admiralty Manual of Scientific Enquiry (1849), pages 156-195. This was written in the spring of 1848.
"On British Fossil Lepadidae," 'Geol. Soc. Journ.' vi., 1850, pages 439-440.
"Analogy of the structure of some Volcanic Rocks with that of Glaciers,"'Edin. Roy. Soc. Proc.' ii., 1851, pages 17-18.
Professor Geikie has been so good as to give me (in a letter dated November 1885) his impressions of my father's article in the 'Admiralty Manual.' He mentions the following points as characteristic of the work:--"1. Great breadth of view. No one who had not practically studied and profoundly reflected on the questions discussed could have written it.
"2. The insight so remarkable in all that Mr. Darwin ever did. The way in which he points out lines of enquiry that would elucidate geological problems is eminently typical of him. Some of these lines have never yet been adequately followed; so with regard to them he was in advance of his time.
"3. Interesting and sympathetic treatment. The author at once puts his readers into harmony with him. He gives them enough of information to show how delightful the field is to which he invites them, and how much they might accomplish in it. There is a broad sketch of the subject which everybody can follow, and there is enough of detail to instruct and guide a beginner and start him on the right track.
"Of course, geology has made great strides since 1849, and the article, if written now, would need to take notice of other branches of inquiry, and to modify statements which are not now quite accurate; but most of the advice Mr. Darwin gives is as needful and valuable now as when it was given. It is curious to see with what unerring instinct he seems to have fastened on the principles that would stand the test of time."In a letter to Lyell (1853) my father wrote, "I went up for a paper by the Arctic Dr. Sutherland, on ice action, read only in abstract, but I should think with much good matter. It was very pleasant to hear that it was written owing to the Admiralty Manual."To give some idea of the retired life which now began for my father at Down, I have noted from his diary the short periods during which he was away from home between the autumn of 1842, when he came to Down, and the end of 1854.
1843 July.--Week at Maer and Shrewsbury.
October.--Twelve days at Shrewsbury.
1844 April.--Week at Maer and Shrewsbury.