skip to content

Darwin Correspondence Project

To W. D. Fox   22 [July 1855]

Down Farnborough Kent


My dear Fox

Many thanks for the 7 days old White Dorking & for the other promised ones.—1 I am getting quite “a chamber of horrors”.2 I appreciate your kindness even more than before; for I have done the black deed & murdered an angelic little Fan-tail & Pouter at 10 days old.—

I tried Chloroform & Ether for the first & though evidently a perfectly easy death it was prolonged; & for the second I tried putting lumps of Cyanide of Potassium in a very large damp Bottle, half-an-hour before putting in the Pigeon, & the prussic acid gas thus generated was very quickly fatal.— I find a lump of this substance kept with a little cotton-wool in small wide-mouthed Bottle, excellent for my Boys, who are ardent Lepidopterists: the gas kills quickly, sometimes almost instantly, & they most rarely revive after 12 an hour immersion.—

Thank you for your letter about mongrels; by the way you deserve a good scolding, by ending your letter with “I will spare you anymore”— I can truly say that I never in my life received a letter from you that did not interest me,—& this particular one on the very subjects, which interest me most!!— I am never weary at marvelling with you at heredetary mental habits, tastes &c.—

I wonder whether it would be possible to get precise information on the cross of greyhound with Bull-Dog, whether as you think, there were traces of the Bull-dog, after 8 generations: I shd. be extremely glad to get such facts. Can you think of any channel? Do you know in the least who made this cross?3

I suppose & fear that it is quite impossible that you shd. have any precise evidence that the Setter is a mongrel,4 as likewise the brown Retriever &c. I observe many writers on these subjects will not believe that any mongrel is ever true to its kind.—5 I remember when you were here you told me many curious facts about Retrievers &c, &c, which I have written down.—

One more question, to the above point, do you know positively that Ld. Hill’s Dorkings were crossed with the Game, & then fetched high prices as Dorkings?6

If I were to apologise, & talk of sparing you, by Jove it would be to the point.—

My dear Fox | Most truly your’s | C. Darwin

This morning Atriplex or Orache seeds germinated after 100 days immersion!—


See letters to W. D. Fox, 7 May [1855], 23 May [1855], 11 June [1855], and 27 [June 1855].
Marie Tussaud’s collection of waxwork figures, established in Baker Street in 1833, included a ‘chamber of horrors’ (EB).
See letter to W. D. Fox, 26 April [1855], n. 4. CD described Lord Orford’s cross between greyhounds and the bulldog to illustrate the effect of crosses modifying old races and forming new ones in Variation 2: 95.
Discussed in Variation 1: 41, where Youatt 1845 is quoted for a description of the setter as a large spaniel improved and taught new ways of marking game.
In Variation 2: 95, CD emphasised that breeds of domestic animals that have previously been crossed for the purpose of improvement do breed true in the present day. He cited Fox concerning pointers having been crossed with foxhounds ‘to give them dash and speed.’
In Variation 2: 95, CD stated: ‘Certain strains of Dorking fowls have had a slight infusion of Game blood’.


EB: The Encyclopædia Britannica. A dictionary of arts, sciences, literature and general information. 11th edition. 29 vols. Cambridge: Cambridge University Press. 1910–11.

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

Youatt, William. 1845. The dog. London.


Describes his method of putting young poultry to death.

Asks questions arising from WDF’s reply about crossed mongrels.

Letter details

Letter no.
Charles Robert Darwin
William Darwin Fox
Sent from
Source of text
Christ’s College Library, Cambridge (MS 53 Fox 95)
Physical description
ALS 6pp

Please cite as

Darwin Correspondence Project, “Letter no. 1728,” accessed on 17 May 2022,

Also published in The Correspondence of Charles Darwin, vol. 5