skip to content

Darwin Correspondence Project

To W. D. Fox   24 August [1866]

Down. | Bromley. | Kent. S.E.

Aug 24th.

My dear Fox

It is always a pleasure to me to hear from you & about you, patriarch as you are with your countless children, & grand children—1 I feel a mere dwarf by your side. My own children are all well & two of my boys are touring in Norway.2 Poor Susan is in a terrible suffering state & I fear there is no hope for her except the one & last hope for all.3

We expect Caroline here with her three girls on Monday & I will give her your kind enquiries.4 As for myself my health is very decidedly better though I am not very strong. I attribute my improvement partly to Bence Jones’ diet & partly, wonderful to relate, to my riding every day which I enjoy much.5 I don’t believe in your theory of moderate mental work doing me any harm—any how I can’t be idle.6 I am making rapid progress with my book on domesticated animals which I fear will be a big one & has been laborious from the number of references.7 I hope to begin printing towards the close of this close of this year & when it is completed I will of course send you a copy, as indeed I am bound to do as I owe much information to you.8 I should have begun printing before this had I not lost nearly three months by the troublesome labour of largely correcting a new edit. of the Origin.9 I think I have heard of hybrids between the Sphinx-moths which you mention; I shall be surprised if the hybrids are fertile10

Believe me, my dear old Friend | yours affectly | Charles Darwin


See letter from W. D. Fox, 20 August [1866]. Fox had sixteen children and five grandchildren (see Correspondence vol. 13, letter from W. D. Fox, 6 January [1865]).
CD refers to George Howard Darwin and Francis Darwin (letter from G. H. Darwin to H. E. Darwin, [June–July 1866] (DAR 251: 2240)). Emma Darwin’s diary (DAR 242) recorded, ‘Boys went to Norway’ on 16 August 1866.
CD’s sister, Susan Elizabeth Darwin, was seriously ill.
The reference is to Caroline Sarah Wedgwood. Her daughters were Katherine Elizabeth Sophy, Margaret Susan, and Lucy Caroline Wedgwood (Freeman 1978, s.v. Josiah Wedgwood III).
CD first consulted Henry Bence Jones in July 1865 and began following the diet he recommended shortly after (see letter to H. B. Jones, 3 January [1866] and nn. 2 and 4). He started riding on 4 June 1866 (Emma Darwin’s diary (DAR 242)); see also letter to John Lubbock, 2 August [1866], n. 2.
CD refers to Variation.
CD sent the manuscript of all but the last chapter of Variation to his publisher in December 1866, but the book was only published in January 1868 (letter to John Murray, 21 and 22 December [1866], and Freeman 1977). In Variation, CD made several references to information received from Fox.
The reference is to the fourth edition of Origin.
Sphinx-moths or hawk-moths, as Fox had referred to them, belong to the family Sphingidae. Fox had reported crossing two species (see letter from W. D. Fox, 20 August [1866] and n. 8).


Correspondence: The correspondence of Charles Darwin. Edited by Frederick Burkhardt et al. 29 vols to date. Cambridge: Cambridge University Press. 1985–.

Freeman, Richard Broke. 1977. The works of Charles Darwin: an annotated bibliographical handlist. 2d edition. Folkestone, Kent: William Dawson & Sons. Hamden, Conn.: Archon Books, Shoe String Press.

Freeman, Richard Broke. 1978. Charles Darwin: a companion. Folkestone, Kent: William Dawson & Sons. Hamden, Conn.: Archon Books, Shoe String Press.

Variation: The variation of animals and plants under domestication. By Charles Darwin. 2 vols. London: John Murray. 1868.


Family news. Describes [final] illness of Susan Darwin [d. 3 Oct 1866]. CD’s health better.

Making rapid progress on Variation.

Has heard of hybrids between moths mentioned by WDF.

Work on [4th] edition of Origin has delayed Variation.

Letter details

Letter no.
Charles Robert Darwin
William Darwin Fox
Sent from
AU25 66
Source of text
Smithsonian Libraries and Archives (Dibner Library of the History of Science and Technology MSS 405 A. Gift of the Burndy Library)
Physical description
LS 4pp

Please cite as

Darwin Correspondence Project, “Letter no. 5197,” accessed on 14 July 2024,

Also published in The Correspondence of Charles Darwin, vol. 14