To Charles Lyell   15 February [1866]1

Down

Thursday | Feb 15th

My dear Lyell

Many thanks for Hooker’s letter.2 It is a real pleasure to me to read his letters, they are alway written with such spirit. I quite agree that Agassiz could never mistake weathered-blocks & glacial action;3 though the mistake has, I know, been made in 2 or 3 quarters of the world. I have often fought with Hooker about the Physicists putting their veto on the world having been cooler; it seems to me as irrational, as if, when Geologists first brought forward some evidence of elevation & subsidence, a former Hooker had declared that this cd not possibly be admitted until Geologists cd explain what made the earth rise & fall.4 It seems that I erred greatly about some of the plants on the Organ Mts.,5 but I am very glad to hear about Fuchsia &c. I cannot make out what Hooker does believe, he seems to admit the former cooler climate, & almost in the same breath, to spurn the idea. To retort Hooker’s words “It is inexplicable to me” how he can compare the transport of seeds from the Andes to the Organs Mts. with that from a continent to an island: not to mention the much greater distance, there are no currents of water from one to the other, & what on earth shd make a bird fly that distance without resting many times.6 I do not at all suppose that nearly all tropical forms were exterminated during the cool period, but in somewhat depopulated areas, into which there cd be no migration, probably many closely allied species will have been formed since this period. Hooker’s paper in Nat. Hist. Rev. is well worth studying; but I cannot remember that he gives good grounds for his conviction that certain orders of plants cd not withstand a rather cooler climate, even if it came on most gradually.7 We have only just learnt under how cool a temperature several tropical Orchids can flourish.8 I clearly saw Hookers difficulty about the preservation of tropical forms during the cool period, & tried my best to retain one spot after another as a hot-house for their preservation; but it wd not hold good, & it was a mere piece of truckling on my part when I suggested that longitudinal belts of the world were cooled one after the other.9 I shall very much like to see Agassiz’ letter whenever you receive one.10

I have written a long letter; but a squabble with or about Hooker always does me a world of good, & we have been at it many a long year. I cannot quite understand whether he attacks me as a Wriggler or a Hammerer but I am very sure that a deal of wriggling has to be done.11

With many thanks | yours affectionately | Charles Darwin

LS(A)

1
The year is established by the relationship between this letter and the letter from J. D. Hooker, 21 February 1866; Lyell apparently sent this letter or a copy of it to Joseph Dalton Hooker.
2
The letter from Lyell, and its enclosure, evidently a letter from Hooker to Lyell, have not been found.
3
On Louis Agassiz’s view that the valley of the Amazon in Brazil was of glacial origin, see the letter from C. F. J. Bunbury to Charles Lyell, 3 February 1866 and nn. 7 and 8, and the letter to Charles Lyell, 7 February [1866]. Agassiz himself wrote of the difficulties of distinguishing between weathered rocks and glacial drift around Tijuca in Brazil (J. L. R. Agassiz and Agassiz 1868, pp. 86–8), and differed from other geologists in Brazil in his interpretation of glacial phenomena in that country (Brice and Figueirôa 2001, pp. 166–72).
4
For an example of earlier correspondence between CD and Hooker on changes in global temperature, see Correspondence vol. 12, letter to J. D. Hooker, [20–]22 February [1864] and nn. 10 and 11. See also letter to Charles Lyell, 7 February [1866] and n. 12. The physicist William Thomson (later Lord Kelvin) had recently calculated the age of the earth on the basis that it had been cooling progressively during geological time (W. Thomson 1865). CD and Hooker had exchanged letters on elevation and subsidence, for example in November 1862; Hooker had protested, ‘I set out on Biological grounds & hold myself as independent of theories of subsidence as you do of the opinions of Physicists on heat of Globe!!’ (Correspondence vol. 10, letter from J. D. Hooker, 2 November 1862).
5
CD had written in Origin, p. 374: ‘On the highest mountains of Brazil, some few European genera were found by Gardner, which do not exist in the wide intervening hot countries.’ In Origin 4th ed., pp. 444–5, this was changed to: ‘On the Organ mountains of Brazil, some few European temperate, some antarctic, and some Andean genera were found by Gardner, which did not exist in the low intervening hot countries.’ CD referred to George Gardner and Gardner 1846b (see also letter to Charles Lyell, 7 February [1866] and nn. 22 and 23).
6
CD and Hooker had long failed to agree on the mechanisms of the geographical distribution of plants (see, for example, Correspondence vol. 5, letter to J. D. Hooker, 7 April [1855], and Correspondence vol. 11, letters from J. D. Hooker, [7 May 1863] and n. 11, and [24 May 1863] and nn. 7 and 8).
7
CD apparently refers to the anonymous review article ‘New colonial floras’ in the Natural History Review n.s. (1865) 5: 46–63. The article contained a section on the vulnerability of plants to intertropical glaciation, with comments on CD’s views about the survival of tropical species. CD previously thought that the review’s author was Daniel Oliver (see Correspondence vol. 13, letter to J. D. Hooker, 19 January [1865] and n. 7); however, Hooker is named as the possible author in ML 1: 479 n. There is an unbound annotated copy of the paper in the Darwin Library–CUL.
8
During 1864, the Gardeners’ Chronicle had published discussions about the temperature of greenhouses for tropical orchids. CD subscribed to the magazine; his copies are in the Cory Library, Cambridge University Botanic Garden. The discussion was generated in part by James Bateman’s ‘Lecture on cool orchids’ (ibid., 21 May 1864, pp. 483–5) and the publication of his pamphlet on the subject (Bateman 1864).
9
Hooker had questioned how tropical species could survive a former cold period, and expressed anxiety over the lack of suitable ‘greenhouse’ temperatures during such a period (see Correspondence vol. 6, letter from J. D. Hooker, 9 November 1856). In Origin, p. 374, CD proposed ‘broad longitudinal belts, having been simultaneously colder from pole to pole’ to explain the ‘distribution of identical and allied species’ across and between continents, although this passage was altered in the fifth and later editions of Origin (Peckham ed. 1959, p. 595). For earlier letters from CD to Hooker concerning the possible migration of temperate species across the equator during a former glacial period, see, for example, Correspondence vol. 13, letter to J. D. Hooker, 19 January [1865] and n. 8, and Correspondence vol. 13, Supplement, letter to J. D. Hooker, [14 November 1858]. For a brief history of CD and Hooker’s differences concerning the geographical distribution of plants, see R. Desmond 1999, pp. 254–60.
10
No such letter has been found.
11
The ability to ‘wriggle’ out of theoretical difficulties had long been a joke between CD and Hooker (see Correspondence vol. 13, letter to J. D. Hooker, 19 January [1865] and n. 9). The word ‘hammerer’ may be used here to mean a geologist (see OED), or may refer to Hooker’s criticism of CD’s ‘sledge-hammer hypothesis’ (see also letter from J. D. Hooker, 21 February 1866).

Manuscript Alterations and Comments

0.2 Feb 15th] added in CD’s hand

Please cite as “DCP-LETT-5007,” in Ɛpsilon: The Charles Darwin Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-5007