To Charles Lyell   [2 September 1849]1

Down Farnborough Kent

Sunday

My dear Lyell

It was very good of you to write me so long a letter which has interested me much; I shd. have answered it sooner, but I have not been very well for the few last days. Your letter has, also, flattered me much in many points.

I am very glad you have been thinking over the relation of subsidence & the accumulation of deposits:2 it has to me removed many great difficulties; please to observe that I have carefully abstained from saying that sediment is not deposited during periods of elevation, but only that it is not accumulated to sufficient thickness to withstand subsequent beach action: on both coasts of S. America, the amount of sediment deposited, worn away & redeposited oftentimes must have been enormous, but still there have been no wide formations produced: just read my discussion (p. 135 of my S. American Book) again with this in your mind.—3

I never thought of your difficulty (ie in relation to this discussion) of where was the land whence the 3 miles of S. Wales strata were derived?4 Do you not think that it may be explained, by a form of elevation, which I have always suspected to have been very common (& indeed had once intended getting all facts together). viz thus diagram

The frequency of a deep ocean close to a rising continent, bordered with mountains, seems to indicate these opposite movements of rising & sinking close together: this wd. easily explain the S. Wales & Eocene cases.— I will only add that I shd think there wd be a little more sediment produced during subsidence than during elevation, from the resulting outline of coast after long period of rise.— There are many points in my vols. which I shd. have liked to have discussed with you, but I will not plague you: I shd like to hear whether you think there is anything in my conjecture on Craters of Elevation;5 I cannot possibly believe that St. Jago or Mauritius are the basal fragments of ordinary volcanos; I wd sooner even admit E. de Beaumont’s view than that; much as I wd sooner in my own mind in all cases follow you.— Just look at p. 232 in my S. America for trifling point,6 which however, I remember, to this day releived my mind of a considerable difficulty.—

I remember being struck with your discussion on the Missisippi beds7 in relation to Pampas, but I shd. wish to read them over again, I have, however, relent your work to Mrs Rich,8 who, like all whom I have met, have been much interested by it.— I will stop about my own geology.— But I see I must mention, that Scroope did suggest (& I have alluded to him, p. 118 but without distinct reference & I fear not sufficiently, though I utterly forget what he wrote9 ) the separation of basalt & trachyte, but he does not appear to have thought about the crystals which I believe to be the Keystone of the phenomenon: I cannot but think this separation of the molten elements has played a great part in the metamorphic rocks: how else cd the basaltic dykes come in great granitic districts such as those of Brazil?— What a wonderful book for labour is D’. Archiac!10

We are going on as usual: Emma desires her kind love to Lady Lyell: she boldly means to come to Birmingham with me & very glad she is that Lady Lyell will be there:11 two of our children have had a tedious slow fever.—12 I go on with my aqueous processes & very steadily but slowly gain health & strength. Against all rules13 I dined at Chevening with Ld. Mahon,14 who did me the grt. honour of calling on me, & how he heard of me, I can’t guess— I was charmed with Lady Mahon, & anyone might have been proud at the praises of agreeableness which came from her beautiful lips with respect to you.— I liked old Ld. Stanhope15 very much; though he abused geology & zoology heartily— “To suppose that the omnipotent God made a world, found it a failure, & broke it up & then made it again & again broke it up, as the geologists say, is all fiddle faddle”.— Describing species of birds & shells &c is all “fiddle faddle”.16 But yet I somehow liked him better than Ld Mahon.—

I am heartily glad we shall meet at Birmingham, as I trust we shall if my health will but keep up.— I work now every day at the Cirripedia for 212 hours & so get on a little but very slowly.— I sometimes after being a whole week employed & having described, perhaps only 2 species agree mentally with Ld. Stanhope that it is all fiddle-faddle: however the other day I got the curious case of a unisexual, instead of hermaphrodite, cirripede, in which the female had the common cirripedial character, & in two of the valves of her shell had two little pockets, in each of which she kept a little husband;17 I do not know of any other case where a female invariably has two husbands.— I have one still odder fact, common to several species, namely that though they are hermaphrodite, they have small additional or as I shall call them Complemental males:18 one specimen itself hermaphrodite had no less than seven of these complemental males attached to it. Truly the schemes & wonders of nature are illimitable.— But I am running on as badly about my Cirripedia as about Geology: it makes me groan to think that probably, I shall never again have the exquisite pleasure of making out some new district,—of evoking geological light out of some troubled, dark region.— So I must make the best of my Cirripedia.—

Remember me most kindly to Mr & Mrs Bunbury.— I am sorry to hear how weak your Father is—19 | Yours most sincerely | C. Darwin

1
The date is based on the endorsement and the dates of the Birmingham British Association meeting. CD left for Birmingham on 11 September 1849. In his health diary (Down House MS) CD recorded that he was well from 20 to 29 August, but that he was ‘Poorly’ and ‘exhausted’ from 30 August to 1 September.
2
Lyell was preparing a paper on ‘craters of denudation’ (C. Lyell 1850a), read to the Geological Society on 19 December 1849, in which the effects of elevation and subsidence on volcanic deposits were discussed.
3
CD’s explanation of the absence of conchiferous deposits as due to denudation and subsidence is in South America, pp. 135–9.
4
The denudation of South Wales had been the subject of much discussion between CD, Lyell, and Andrew Crombie Ramsay (see Correspondence vol. 3, letter to Charles Lyell, [3 October 1846], and letter to A. C. Ramsay, 10 October [1846]). Lyell did not, however, discuss South Wales in C. Lyell 1850a but rather in his anniversary address to the Geological Society on 15 February 1850 (C. Lyell 1850b, pp. liii, liv–vi).
5
This was the name given by Christian Leopold von Buch, and adopted by Jean Baptiste Armand Louis Léonce élie de Beaumont, to the theory originally proposed by Alexander von Humboldt that volcanic cones were formed by upward pressure, rather than by the eruption of lava through vents. Such pressure raised originally horizontal layers into a dome that was easily broken through. Lyell had opposed this view as early as 1830 in the first volume of his Principles of geology (C. Lyell 1830–3). For a history of the controversy see Dean 1980. CD speculated that the mountains might still be considered ‘craters of elevation’ by slow elevation, in which the central hollows were formed ‘not by the arching of the surface, but simply by that part having been raised to a less height’ (Volcanic Islands, p. 96).
6
On p. 232 of South America, CD discussed the ‘Eruptive Sources of the Porphyritic Claystone and Greenstone Lavas’ and suspected that the difficulty of tracing the streams of porphyries to their ancient eruptive sources was because ‘the original points of eruption tend to become the points of injection’.
7
Lyell delivered a lecture about the delta of the Mississippi River at the Royal Institution on 8 June 1849 and published a detailed account in C. Lyell 1849, 2: 242–56. CD presumably refers to the latter, which is in the Darwin Library–CUL.
8
Mary Rich, née Mackintosh, Fanny Mackintosh Wedgwood’s half-sister.
9
Scrope 1825. CD’s copy (unannotated) is in the Darwin Library–Down. See Volcanic islands, p. 118.
10
Archiac 1847–60, volumes one and two, in which étienne Jules Adolphe Desmier de Saint-Simon, Vicomte d’Archiac, summarised the progress of French geology from 1834–45. CD’s copy of volume one is in the Darwin Library–Down.
11
The British Association was due to meet in Birmingham, 12–19 September 1849. Lyell was president of section C (geology and physical geography); CD was a vice-president of the association. According to her diary, Emma followed CD to Birmingham on 12 September.
12
According to Emma Darwin’s diary, Henrietta Darwin developed a fever on 5 July and William Darwin fell ill on 11 July. William did not come ‘down stairs’ until 30 July, and he suffered a relapse on 16 August.
13
The ‘rules’ set out by James Manby Gully for CD’s water therapy at home.
14
Philip Henry Stanhope, Viscount Mahon, later 5th Earl Stanhope. Chevening, in Kent, was the family seat.
15
Philip Henry Stanhope, 4th Earl Stanhope, father of Viscount Mahon.
16
In the Autobiography CD mentioned that the Earl once said to him, ‘Why don’t you give up your fiddle-faddle of geology and zoology, and turn to the occult sciences?’ (p. 112).
17
Ibla cumingii (see Living Cirripedia (1851): 189–203).
18
The complemental males of Scalpellum, first mentioned in letter to J. L. R. Agassiz, 22 October 1848. See Living Cirripedia (1851): 231–43 and 281–93.
19
Charles Lyell Sr died on 8 November 1849.

Manuscript Alterations and Comments

2.5 subsequent] interl
2.6 worn] after del illeg
2.6 oftentimes] interl
2.8 (p. 135 of my S. American Book)] interl
3.5 thus] added
4.2 these] altered from ‘the’
4.2 movements] ‘s’ added
4.2 of rising & sinking] interl
4.5 outline] after del ‘for’
4.8 Elevation] ‘E’ over ‘e’
4.9 basal] interl
4.10 even] interl
4.10 view] interl
4.11 in all cases] interl
5.2 shd.] ‘s’ over ‘w’
5.5 p. 118] interl
5.7 thought] after del ‘known’
5.10 how] after del ‘where’; over illeg
6.13 Mahon] after del ‘Stanhope’
7.2 so get] after del ‘never’
7.5 unisexual, instead of hermaphrodite, 7.6] interl after del ‘bisexual’
7.11 itself hermaphrodite 7.12] interl
7.13 are] after del ‘of’
7.15 again] interl
7.16 So I] ‘I’ over illeg

Please cite as “DCP-LETT-1252,” in Ɛpsilon: The Charles Darwin Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-1252