My dear Sir

I am very much obliged for your extremely kind letter & for your several presents.² Although your appreciation of my work is certainly too high, yet it is very encouraging to me, especially as yesterday I read two pamphets, just published in England, in which every form of abuse is heaped on me.³ I am called, for instance, a “filthy dreamer”.— You seem to be doing splendid work in physiology, the noblest of sciences, as I have long thought it. What you say about the differences of the blood-crystals is truly astonishing.⁴ I am also much interested by what you say of the different effect of Prussic acid on different individuals of the same species: I remember some years ago wishing in vain for information on this head. I think it arose from observing how differently in quickness (whether due to rate of respiration or to direct action of the poison I could not tell) the vapour acted on different insects. I remember Bees died instantly, but (I think,) it was a Longicorn beetle which resisted all effects for an astonishing time.—⁵

R. W. Darwin is my Father, but I believe he was greatly aided in his paper on optics by his Father Erasmus D.⁶

I have really nothing of interest about myself, but as you desire it, I will scribble whatever occurs to me.— I derived no advantage from the Lectures at Edinburgh, for they were infinitely dull & cured me of any taste for Geology for 3 years. D^r Grant⁷ was not a Professor, but worked at zoology out of pure love, & his Society was a great encouragement. I used to amuse myself with examining marine animals, but I did so solely for amusement. I believe I was the first person who ever saw the earliest locomotive egg-like state of a Bryozoon: I showed it to Grant, who stated so at the meeting of the Wernerian Nat. Hist. Soc. & this little discovery was an immense encouragement.—⁸ I was disgusted at anatomy & attended only 2 or 3 Lectures & this has been ever since an irreparable loss to me.— When I went to Cambridge, I became a most enthusiastic collector of Coleoptera; but again only for amusement. If any one told me the name of a Beetle, I thought I knew all that anyone could desire; & I believe I never ever looked even at the oral organs of any insect! Yet I worked like a slave at collecting. Henslow’s Society was a great charm & benefit to me, & I liked much his Lecture on Botany.⁹ All my early life I was mad for collecting, minerals, shells, plants, Bird-skins have all had their turn. Near the end of my Cambridge life Henslow persuaded me to begin Geology. I was always very fond of observing the habits of Birds, & White’s Nat. Hist. of Selborne,¹⁰ thus had much influence on my mind. But of all books, Humboldt’s Travels had by far the greatest influence—¹¹ I read large parts over & over again.— I had nearly managed to get a party to go to the Canary Isl^ds, when the offer of joining the Beagle was made to me & joyfully accepted.¹² I suppose, however, no ever started worse prepared than I was except as a mere collector. I knew nothing of anatomy, & had never read any systematic work on Zoology— I had never touched a compound microscope & had begun Geology for only about 6 months. But I took out plenty of Books¹³ & worked as hard as I could & dissected roughly all sorts of the lower marine animals. Here I felt fearfully the want of practice & knowledge. My education in fact began on board the Beagle. I remember nothing previously which deserved to be called education except some experimental work at chemistry when a school-boy with my Brother.—¹⁴ No doubt collecting largely in so many branches had improved my powers of observation.—

I never wrote so much about myself in my life, & I hope it may be worth your reading, but I doubt.—

Believe me, my dear Sir | Yours sincerely | Ch. Darwin

I do not know whether you will care to see extracts from my letters printed by Prof. Henslow, but I send a copy by this Post.—¹⁵