What labour you must be undergoing now; I have wondered at your patience in having written to me two such long notes. How glad Mrs. Horner will be when your address is completed. (558/3. Anniversary Address of the President ("Quart. Journ. Geol. Soc." Volume III., page xxii, 1847).) I must say that I am much pleased that you will notice my volume in your address, for former Presidents took no notice of my two former volumes.
I am exceedingly glad that Bunbury is going on well.
LETTER 559. TO C. LYELL. Down, July 3rd {1849}.
I don't know when I have read a book so interesting (559/1. "A Second Visit to the United States of North America." 2 volumes, London, 1849.); some of your stories are very rich. You ought to be made Minister of Public Education—not but what I should think even that beneath the author of the old "Principles." Your book must, I should think, do a great deal of good and set people thinking. I quite agree with the "Athenaeum" that you have shown how a man of science can bring his powers of observation to social subjects. (559/2. "Sir Charles Lyell, besides the feelings of a gentleman, seems to carry with him the best habits of scientific observation into other strata than those of clay, into other 'formations' than those of rock or river-margin." "The Athenaeum," June 23rd, 1849, page 640.) You have made H. Wedgwood, heart and soul, an American; he wishes the States would annex us, and was all day marvelling how anyone who could pay his passage money was so foolish as to remain here.
LETTER 560. TO C. LYELL. Down, {December, 1849}.
(560/1. In this letter Darwin criticises Dana's statements in his volume on "Geology," forming Volume X. of the "Wilkes Exploring Expedition," 1849.)
...Dana is dreadfully hypothetical in many parts, and often as "d—d cocked sure" as Macaulay. He writes however so lucidly that he is very persuasive. I am more struck with his remarks on denudation than you seem to be. I came to exactly the same conclusion in Tahiti, that the wonderful valleys there (on the opposite extreme of the scale of wonder {to} the valleys of New South Wales) were formed exclusively by fresh water. He underrates the power of sea, no doubt, but read his remarks on valleys in the Sandwich group. I came to the conclusion in S. America (page 67) that the main effect of fresh water is to deepen valleys, and sea to widen them; I now rather doubt whether in a valley or fiord...the sea would deepen the rock at its head during the elevation of the land. I should like to tour on the W. coast of Scotland, and attend to this. I forget how far generally the shores of fiords (not straits) are cliff-formed. It is a most interesting subject.
I return once again to Coral. I find he does not differ so much in detail with me regarding areas of subsidence; his map is coloured on some quite unintelligible principle, and he deduces subsidence from the vaguest grounds, such as that the N. Marianne Islands must have subsided because they are small, though long in volcanic action: and that the Marquesas subsided because they are penetrated by deep bays, etc., etc. I utterly disbelieve his statements that most of the atolls have been lately raised a foot or two. He does not condescend to notice my explanation for such appearances. He misrepresents me also when he states that I deduce, without restriction, elevation from all fringing reefs, and even from islands without any reefs! If his facts are true, it is very curious that the atolls decrease in size in approaching the vast open ocean S. of the Sandwich Islands. Dana puts me in a passion several times by disputing my conclusions without condescending to allude to my reasons; thus, regarding S. Lorenzo elevation, he is pleased to speak of my "characteristic accuracy" (560/2. Dana's "Geology" (Wilkes expedition), page 590.), and then gives difficulties (as if his own) when they are stated by me, and I believe explained by me—whereas he only alludes to a few of the facts. So in Australian valleys, he does not allude to my several reasons. But I am forgetting myself and running on about what can only interest myself. He strikes me as a very clever fellow; I wish he was not quite so grand a generaliser. I see little of interest except on volcanic action and denudation, and here and there scattered remarks; some of the later chapters are very bald.
LETTER 561. TO J.D. DANA. Down, December 5th, 1849.
I have not for some years been so much pleased as I have just been by reading your most able discussion on coral reefs. I thank you most sincerely for the very honourable mention you make of me. (561/1. "United States Exploring Expedition during the Years 1839-42 under the Command of Charles Wilkes, U.S.N." Volume X., "Geology," by J.D. Dana, 1849.) This day I heard that the atlas has arrived, and this completes your munificent present to me. I have not yet come to the chapter on subsidence, and in that I fancy we shall disagree, but in the descriptive part our agreement has been eminently satisfactory to me, and far more than I ever ventured to anticipate. I consider that now the subsidence theory is established. I have read about half through the descriptive part of the "Volcanic Geology" (561/2. Part of Dana's "Geology" is devoted to volcanic action.) (last night I ascended the peaks of Tahiti with you, and what I saw in my short excursion was most vividly brought before me by your descriptions), and have been most deeply interested by it. Your observations on the Sandwich craters strike me as the most important and original of any that I have read for a long time. Now that I have read yours, I believe I saw at the Galapagos, at a distance, instances of those most curious fissures of eruption. There are many points of resemblance between the Galapagos and Sandwich Islands (even to the shape of the mound-like hills)—viz., in the liquidity of the lavas, absence of scoriae, and tuff-craters. Many of your scattered remarks on denudation have particularly interested me; but I see that you attribute less to sea and more to running water than I have been accustomed to do. After your remarks in your last very kind letter I could not help skipping on to the Australian valleys (561/3. Ibid., pages 526 et seq.: "The Formation of Valleys, etc., in New South Wales."), on which your remarks strike me as exceedingly ingenious and novel, but they have not converted me. I cannot conceive how the great lateral bays could have been scooped out, and their sides rendered precipitous by running water. I shall go on and read every word of your excellent volume.