My dear Susan

I received a few days since your letter of November: the three letters, which I before mentioned are yet missing: but I do not doubt they will come to life.— I returned a week ago from my excursion across the Andes to Mendoza. Since leaving England I have never made so successful a journey: it has however been very expensive: I am sure my Father would not regret it, if he could know how deeply I have enjoyed it.— it was something more than enjoyment: I cannot express the delight, which I felt at such a famous winding up of all my geology in S.— America.— I literally could hardly sleep at nights for thinking over my days work.— The scenery was so new & so majestic: every thing at an elevation of 12000 ft. bears so different an aspect, from that in a lower country.— I have seen many views more beautiful but none with so strongly marked a character. To a geologist also there are such manifest proofs of excessive violence, the strata of the highest pinnacles are tossed about like the crust of a broken pie. I crossed by the Portillo pass, which at this time of year is apt to be dangerous, so could not afford to delay there; after staying a day in the stupid town of Mendoza I began my return by Uspallata, which I did very leisurely.— My whole trip only took up 22 days.— I travelled with, for me, uncommon comfort, as I carried a bed!: my party consisted of two Peons & 10 mules, two of which were with baggage or rather food, in case of being snowed up.— Every thing however favoured me, not even a speck of this years Snow had fallen on the road.—

I do not suppose, any of you can be much interested in Geological details, but I will just mention my principal, results: beside understanding to a certain extent, the description & manner of the force, which has elevated this great line of mountains, I can clearly demonstrate, that one part of the double line is of a age long posterior to the other. In the more ancient line, which is the true chain of the Andes.—I can describe the sort & order of the rocks which compose it. These are chiefly remarkable by containing a bed of Gypsum nearly 2000 ft thick: a quantity of this substance I should think unparalleled in the world. What is of much greater consequence, I have procured fossil shells (from an elevation of 12000 ft) I think an examination of these will give an approximate age to these mountains as compared to the Strata of Europe: In the other line of the Cordilleras there is a strong presumption (in my own mind conviction) that the enormous mass of mountains, the peaks of which rise to 13 & 14000 ft are so very modern as to be contemporaneous with the plains of Patagonia (or about with upper strata of Isle of Wight): If this result shall be considered as proved it is a very important fact in the theory of the formation of the world.— Because if such wonderful changes have taken place so recently in the crust of the globe, there can be no reason for supposing former epochs of excessive violence.— These modern strata are very remarkable by being threaded with metallic veins of Silver, Gold, Copper &c: hitherto, these have been considered as appertaining to older formations. In these same beds (& close to a Gold mine) I found a clump of petrified trees, standing upright, with the layers of fine Sandstone deposited round them, bearing the impression of their bark. These trees are covered by other Sandstones & streams of Lava to the thickness of several thousand feet. These rocks have been deposited beneath water, yet it is clear the spot where the trees grew, must once have been above the level of the sea, so that it is certain the land must have been depressed by at least as many thousand feet, as the superincumbent subaqueous deposits are thick.— But I am afraid you will tell me, I am prosy with my geological descriptions & theories.—

You are aware, that plants of Arctic regions are frequently found in lower latitudes, at an elevation which produces an equal degree of cold.— I noticed a rather curious illustration of this law in finding on the patches of perpetual Snow, the famous Red Snow of the Northern Navigators.— I am going to send to Henslow, a description of this little Lichen, for him, if he thinks it worth while to publish in some of the Periodicals.—

I am getting ready my last Cargo of Specimens to send to England; This last trip has added half a mule’s load; for without plenty of proof I do not expect a word of what I have above written to be believed.— I arrived at this place a week since, & am as before living with Corfield. I have found him as kind & good-natured a friend as he is a good man.— I staid also a week in St Iago, to rest after the Cordilleras, of which I stood in need & lived in the house of M^r Caldcleugh (the author of some bad travels in S. America): he is a very pleasant person & took an infinite degree of trouble for me.— It is quite surprising how kind & hospitable I have found all the English merchants.— Do mention to M^r Corfield of Pitchford, under what obligations I lie to his son.— Amongst the various pieces of news, of which your letter is full, I am indeed very sorry to hear of poor Col. Leighton’s death. I can well believe how much he is regretted. It is a bitter reflection, when I think what changes will have taken place before I return. I pray to Heaven I may return to see all of you.—

When you write to the West Indies or Madeira, remember me most affectionately to Charlotte, I hope she will be happy there. When I enjoyed talking over all my schemes with her; how little did she expect to be so soon under a vertical sun & glowing atmosphere.— I am surprised at any Husband liking to take his Wife to such a country.—

The Beagle after leaving me here, returned to Concepcion: Capt Fitz Roy has investigated with admirable precision the relative level of land & Water, since the great Earthquake.— The rise is unequal & parts of the coast are now settling down again, probably at each little trembling which yet continue.— The Is^d of S. Maria has been elevated 10 feet: Capt Fitz Roy found a bed of Muscles with putrid fish that many feet above high water mark.— The Beagle passed this port yesterday. I hired a boat & pulled out to her. The Capt is very well; I was the first to communicate to him his promotion. He is fully determined, nothing shall induce him to delay the voyage a month: if time is lost in one place, something else shall be sacrificed.— Our voyage now will solely consist in carrying a chain of longitudes between important positions.¹

My holidays extend till the middle of July: so that I have 10 weeks before me, & the Beagle will pick me up at any Port I choose. The day after tomorrow I start for Coquimbo. I have three horses & a baggage Mule, & a Peon whom I can trust, having now accompanied me on every excursion. The people moreover to the North, have a capital character for honesty, ie they are not cut- throats. The weather there also will not be hot & it never rains.— I shall extend my journey to Copiapo.—it is a great distance, but I feel certain I shall be most amply repaid. Everything which can interest a Geologist, is found in those districts, Mines of Rock-Salt, Gypsum, Saltpetre, Sulphur; the rocks threaded with metallic veins: old sea-beachs;—curious formed valleys; petrified shells, Volcanoes & strange scenery. The country geologically is entirely unknown (as indeed is the whole of South S. America), & I thus shall see the whole of Chili from the Desert of Atacama to the extreme point of Chiloe. All this is very brilliant, but now comes the black & dismal part of the Prospect.—that horrid phantom, money. The country where I am going to is very thinly inhabited & it will be impossible to draw bills.— I am therefore obliged to draw the money here & transmit it there.— Moreover it is necessary to be prepared for accidents: horses stolen.—I robbed.—Peon sick, a pretty state I should be 400 or 500 miles from where I could command money.— In short, I have drawn a bill for £100: : 0: : 0, & this so shortly after having spent 60 in crossing the Andes. In September we leave the coast of America: & my Father will believe, that I will not draw money in crossing the Pacific, because I can not.— I verily believe I could spend money in the very moon.— My travelling expences are nothing; but when I reach a point, as Coquimbo, whilst my horses are resting, I hear of something very wonderful 100 miles off. A muleteer offers to take me for so many dollars, & I cannot or rather never have resisted the Temptation.—

My Fathers patience must be exhausted: it will be patience smiling at his son, instead of at grief. I write about it as a good joke, but upon my honor I do not consider it so.— Corfield cashes the bill & sends it to his Father, who will bring it to the old Bank, where I suppose it can be transacted.—

I received a long & affectionate letter from Fox: he alludes to a letter which I have never received. I shall write to him from Lima; at present I have my hands full.— How strange it sounds to hear him talk of “his dear little wife”. Thank providence he did not marry the simple charming Bessy.— I shall be very curious to hear a verdict concerning the merits of the Lady.— How the world goes round; Eyton married. I hope he will teach his wife to sit upright.— I have written to him: I am sure he deserves to be happy.— What are the two younger sons doing. I think, from what I saw at Cambridge, Tom is worth the pair.—

Your account of Erasmus’ (does Erasmus live with the Hensleigh’s for the last year their names have never in any letter been separated) visit to Cambridge has made me long to be back there. I cannot fancy anything more delightful than his Sunday round, of King’s, Trinity & those talking giants, Whewell & Sedgwick: I hope your musical tastes continue in due force. I shall be ravenous for the Piano-forte. Do you recollect, poor old Granny, how I used to torment your quiet soul every evening?— I have not quite determined whether I will sleep at the Lion, the first night, when I arrive per Wonder or disturb you all in the dead of the night, everything short of that is absolutely planned.— Everything about Shrewsbury is growing in my mind bigger & more beautiful; I am certain the Acacia & Copper Beech are two superb trees: I shall know every bush, & I will trouble you young ladies, when each of you cut down your tree to spare a few. As for the view behind the house I have seen nothing like it. It is the same with North Wales. Snowden to my mind, looks much higher & much more beautiful than any peak in the Cordilleras. So you will say, with my benighted faculties, it is time to return, & so it is, & I long to be with you— Whatever the trees are, I know what I shall find all you.— I am writing nonsense—so Farewell.— My most affectionate love to all & I pray forgiveness from my Father. Yours most affectionately | Charles Darwin—

You send my letters to Marianne, so I do not send my particular love to her— I suppose her young gentlemen will be a small troop of Grenadiers by the time I return.— What a gang of little ones have come into the world, since I left England.—