My dear Henslow.—

I have delayed writing to you till this period as I was determined to have a fair trial of the voyage. I have so many things to write about, that my head is as full of oddly assorted ideas, as a bottle on the table is with animals.— You being my chief Lord of the Admiralty, must excuse this letter being full of my’s & I’s.— After our two attempts to put to sea in spite of the S.W.^ly gales, the time at Plymouth passed away very unpleasantly.— I would have written, only I had nothing to say, excepting what had better be left unsaid: so that I only wrote to Shrewsbury.— At length we started on y^e 27^th of December with a prosperous wind, which has lasted during our whole voyage:— The two little peeps at seasick misery gave me but a faint idea of what I was going to undergo.— Till arriving at Teneriffe (we did not touch at Madeira) I was scarcely out of my hammock & really suffered more than you could well imagine from such a cause.— At Santa Cruz, whilst looking amongst the clouds for the Peak & repeating to myself Humboldts sublime descriptions, it was announced we must perform 12 days strict quarantine.— We had made a short passage so “Up Jib” & away for St Jago.— You will say all this sounds very bad, & so it was: but from that to the present time it has been nearly one scene of continual enjoyment.— A net over the stern kept me at full work, till we arrived at St Jago: here we spent three most delightful weeks.— The geology was preeminently interesting & I believe quite new:² there are some facts on a large scale of upraised coast (which is an excellent epoch for all the Volcanic rocks to [be] dated from) that would interest M^r. Lyell.—³ One great source of perplexity to me is an utter ignorance whether I note the right facts & whether they are of sufficient importance to interest others.— In the one thing collecting, I cannot go wrong.— St Jago is singularly barren & produces few plants or insects.—so that my hammer was my usual companion, & in its company most delightful hours I spent.—

On the coast I collected many marine animals chiefly gasteropodous (I think some new).— I examined pretty accurately a Caryophyllea & if my eyes were not bewitched former descriptions have not the slightest resemblance to the animal.— I took several specimens of an Octopus, which possessed a most marvellous power of changing its colours; equalling any chamaelion, & evidently accommodating the changes to the colour of the ground which it passed over.—yellowish green, dark brown & red were the prevailing colours: this fact appears to be new, as far as I can find out.— Geology & the invertebrate animals will be my chief object of pursuit through the whole voyage.— We then sailed for Bahia, & touched at the rock of St Paul.— This is a Serpentine formation.— Is it not the only island in the Atlantic which is not Volcanic?—⁴ We likewise staid a few hours at Fernando Noronha; a tremendous surf was running, so that a boat was swamped, & the Captain would not wait.— I find my life on board, when we are in blue water most delightful; so very comfortable & quiet: it is almost impossible to be idle, & that for me is saying a good deal.— Nobody could possibly be better fitted out in every respect for collecting than I am: many cooks have not spoiled the broth this time; M^r Brownes little hints about microscopes &c have been invaluable.— I am well off in books, the Dic: Class: is most useful.— If you should think of any thing or book that would be useful to me; if you would write one line E Darwin Whyndham Club⁵ St James Sq^r.— He will procure them, & send them with some other things to Monte Video, which for the next year will be my head quarters.— Touching at the Abrolhos, we arrived here on April 4^th; when amongst others I received your most kind letter: you may rely on it, during the evening, I thought of the many most happy hours I have spent with you in Cambridge.— I am now living at Botofogo, a village about a league from the city, & shall be able to remain a month longer.— The Beagle has gone back to Bahia, & will pick me up on its return.— There is a most important error in the longitude of S America, to settle which this second trip has been undertaken.— Our Chronometers at least 16 of them, are going superbly: none on record ever have gone at all like them.— A few days after arriving I started on an expedition of 150 miles to Rio Macaò, which lasted 18 days.— Here I first saw a Tropical forest in all its sublime grandeur.— Nothing, but the reality can give any idea, how wonderful, how magnificent the scene is.— If I was to specify any one thing I should give the preemenence to the host of parasitical plants.— Your engraving⁶ is exactly true, but underates, rather than exagerates the luxuriance.— I never experienced such intense delight.— I formerly admired Humboldt, I now almost adore him; he alone gives any notion, of the feelings which are raised in the mind on first entering the Tropics.—

I am now collecting fresh-water & land animals: if what was told me in London is true, viz that there are no small insects in the collections from the Tropics.— I tell Entomologists to look out & have their pens ready for describing.— I have taken, as minute (if not more so) as in England, Hydropori, Hygroti, Hydrobii, Pselaphi, Staphylini, Curculio, Bembididous insects &c &c.— It is exceedingly interesting observing the difference of genera & species from those which I know. it is however much less than I had expected I am at present red-hot with Spiders, they are very interesting, & if I am not mistaken, I have already taken some new genera.— I shall have a large box to send very soon to Cambridge, & with that I will mention some more Natural History particulars.

The Captain does every thing in his power to assist me, & we get on very well.—but I thank my better fortune he has not made me a renegade to Whig principles: I would not be a Tory, if it was merely on account of their cold hearts about that scandal to Christian Nations, Slavery.— I am very good friends with all the officers; & as for the Doctor he has gone back to England.—as he chose to make himself disagreeable to the Captain & to Wickham    He was a philosopher of rather an antient date; at St Jago by his own account he made general remarks during the first fortnight & collected particular facts during the last.—

I have just returned from a walk, & as a specimen how little the insects are know.—Noterus, according to Dic Class. contains solely 3 European species, I, in one hawl of my net took five distinct species.— is this not quite extraordinary?.—

June 16^th.— I have determined not to send a box till we arrive at Monte Video.—it is too great a loss of time both for Carpenters & myself to pack up whilst in harbor.— I am afraid when I do send it, you will be disappointed, not having skins of birds & but very few plants, & geological specimens small: the rest of the things in bulk make very little show.—

I received a letter from Herbert, stating that you have a vol: of Dic Class— Will you send it to Whyndam Club.— I suppose you are at this moment in some sea-port, with your pupils.— I hope for their & your sake, that there will be but few rainy mathematical days.— How I should enjoy one week with you: quite as much as you would one in the glorious Tropics.—

We sail for Monte Video at the end of this month (June) so that I shall have been here nearly 3 months.— this has been very lucky for me.—as it will be some considerable period before we again cross the Tropic.— I am sometimes afraid I shall never be able to hold out for the whole voyage. I believe 5 years is the shortest period it will consume.— The mind requires a little case-hardening, before it can calmly look at such an interval of separation from all friends.— Remember me most kindly to M^rs. Henslow & the ⁠⟨⁠t⁠⟩⁠wo Signoritas; also to L. Jenyns, M^r Dawes ⁠⟨⁠    ⁠⟩⁠ M^r Peacock.— Tell Prof: Sedgwick he does not know how much I am indebted to him for the Welch expedition.— it has given me an interest in geology, which I would not give up for any consideration.— I do not think I ever spent a more delightful three weeks, than in pounding the NW mountains.— I look forward to the Geology about M. Video—as I hear there are slate there, so I presume in that district I shall find the junction of the Pampas of the enormous granite formation of Brazils.— At Bahia the Pegmatite & gneiss in beds had same direction as observed by Humboldt prevailing over Columbia, distant 1300 miles: is it not wonderful?—

M Video will be for long time my direction:— I hope you will write again to me.— there is nobody, from whom I like receiving advice so much as from you.—

I shall be much obliged if you will get one of the engravings of poor M^r Ramsay & keep it for me.— Excuse this almost unintelligible letter & believe me dear Henslow—with the warmest feelings of respect & friendship | Yours affectionately | Chas Darwin *S 2

June. 16^th.—

P.S. I found the other day a beautiful Hymenophallus, (but broke it to pieces in bringing home) & with it an accompanying Leiodes.—a most perfect copy of the Barmouth specimen.—⁷