Thanks ACR for paper and comments on it ["On the denudation of South Wales", Mem. Geol. Surv. G. B. 1 (1846): 297–335].
Sends copy of South America.
Discusses action of the sea.
Criticises ACR's views on sudden elevation of mountain chains.
Down Farnborough Kent
Having just read your excellent memoir on Denudation, I have taken the liberty to send you a copy of my volume on S. America, finding that we have discussed some related questions.— I wish I had profited by your memoir before publishing my volume.— I see that we entirely agree on the sea's great power compared with ordinary alluvial action, & likewise on the frequency of grand oscillations of level & on several other points. If you had time to read parts of my volume, I should much like to discuss with you many cases, such as my notion of subsidence being necessary for the formation of high sea-cliffs, as inferred from the nature of the sea's bottom off them, likewise the horizontal elevation of the Cordillera, as inferred from the sloping gravel fringes in the valleys —on the non-horizontality of lines of escarpments round old bays, &c &c—
I grieve to see how diametrically opposite our views are (I being a follower of Lyell)
on the probability of great & sudden elevations of mountain-chains: I cannot but
think, that you would have estimated existing forces, as more than
“petty” & entertained some doubt about their being
“conflicting” had you inspected with
your own eyes the wide area of recently elevated & similarly affected districts
in S. America. There is much which I could say on this head, but I will not
intrude on you. May I ask, whether you do not admit M
But I much fear that I have cause to apologise for having written at such unreasonable length: the interest excited in me by your Memoir, must plead my excuse, & trusting that you will forgive the liberty I have taken | I remain, dear Sir | Yours faithfully | C. Darwin
- f1 1008.f1Ramsay 1846.
- f2 1008.f2See South America, pp. 25–6, and letter to Charles Lyell, [3 October 1846], n. 3.
- f3 1008.f3CD believed that gravel terraces along the valleys of the Cordillera were marine deposits laid down as the land was gradually elevated (South America, pp. 62–7).
- f4 1008.f4CD believed that the non-horizontal inclination of step-like terraces along the valleys of Coquimbo and Guasco was due to the elevation of land around bays (South America, pp. 41–6).
- f5 1008.f5See letter to Charles Lyell, [3 October 1846], especially n. 6.
- f6 1008.f6Hopkins 1838. See letter to Charles Lyell, [3 October 1846], n. 7.