To W. D. Fox 4 September 
Down Farnborough Kent
My dear Fox
I was much pleased to get your very agreeable letter with all its curious facts on the female sex & their hereditariness. Undoubtedly the periodical shedding of the nails almost by itself wd have convinced any naturalist that the individual was specifically distinct. I wonder whether the queries addressed to about the specific distinctions of the races of man are a reflexion from Agassiz’s Lectures in the U.S. in which he has been maintaining the doctrine of several species,1 —much, I daresay, to the comfort of the slave-holding Southerns.— Your aphorism that “any remedy will cure any malady” contains, I do believe, profound truth,—whether applicable or not to the wondrous Water Cure I am not very sure.— The Water-Cure, however, keeps in high favour, & I go regularly on with douching &c &c:2 I am much in the same state as I have been for the last nine months, & not quite so brilliantly well as I was in the dead of last winter.3 To be as I am, though I never have my stomach right for 24 hours, is, compared to my state two years ago, of inestimable value.
My wife & all my children are well; & they, the children, are now seven in number; to what I am to bring up my four Boys, even already sorely perplexes me. My eldest boy4 is showing the hereditary principle, by a passion for collecting Lepidoptera. We are at present very full of the subject of schools; I cannot endure to think of sending my Boys to waste 7 or 8 years in making miserable Latin verses, & we have heard some good of Bruce Castle School, near Tottenham5 which is partly on the Fellenberg System,6 & is kept by a Brother of Rowland Hill of the Post-office, so that on Friday we are going to inspect it & the Boys.7 I feel that it is an awful experiment to depart from the usual course, however bad that course may be.— Have you, who have something of an omniscient tendency in you, ever heard anything of this school?—
You speak about Homœopathy; which is a subject which makes me more wrath, even than does Clair-voyance: clairvoyance so transcends belief, that one’s ordinary faculties are put out of question, but in Homœopathy common sense & common observation come into play, & both these must go to the Dogs, if the infinetesimal doses have any effect whatever. How true is a remark I saw the other day by Quetelet, in respect to evidence of curative processes, viz that no one knows in disease what is the simple result of nothing being done, as a standard with which to compare Homœopathy & all other such things.8 It is a sad flaw, I cannot but think in my beloved Dr Gully, that he believes in everything— when his daughter was very ill, he had a clair-voyant girl to report on internal changes, a mesmerist to put her to sleep—an homœopathist, viz Dr. Chapman;9 & himself as Hydropathist!10 & the girl recovered.—
My dear Fox, I do hope we shall sometime see you here again. Your affectionate friend | C. Darwin
By pure accident a bundle of Athenæums have been much delayed.
Has heard that Louis Agassiz maintains the doctrine of several species of man "much I daresay to the comfort of the slave-holding southerners".
Homeopathy excites his wrath even more than clairvoyance.