Letter from C. Humboldt to C. Fourcroy, Member of the French National Inſtitute. Cumana, October 16, 1800. The capture of the iſland of Curacao, by the Engliſh and the Americans, having obliged the agent of the republic, C. Breſſot, and general Jeannet to re-embark their troops, in order to return to Guadaloupe, they have put into this port for want of proviſions; and though they intend to remain only twenty-four hours, I have endeavoured to collect for you ſome objects worthy of your attention, and which I hope will reach you in ſafety. You are well enough acquainted with the nature of my travels, and the difficulty and expenſe attending conveyance in the centre of a vaſt continent, to know that my object is rather to collect ideas than things. A ſociety of naturaliſts ſent out by government, accompanied with painters, collectors, packers, &c., might be able to embrace all the detail of the deſcriptive part of natural hiſtory, and, no doubt, would do ſo; but a private perſon, of a very moderate fortune, who undertakes a voyage round the world, ought to confine himſelf to objects more intereſting. To ſtudy the formation of the globe, and the ſtrata which compoſe it; to analyſe the atmoſphere; to meaſure, with the moſt accurate inſtruments, its elaſticity, its temperature, its humidity, its electric and magnetic charge; to obſerve the influence of climate on the animal and vegetable œconomy; to compare, on a grand ſcale, the chemiſtry and phyſiology of organized beings; — ſuch is the labour which I have propoſed. But, without loſing ſight of this principal object of my voyage, you may readily conceive that, with much zeal and a little activity, two men, who traverſe an unknown continent, may at the ſame time collect a great many things, and make a great many obſervations. During the ſixteen months we have been traverſing the vaſt territory ſituated between the coaſt, the Orenoquo, Rio- Nigro, and the river of the Amazons, C. Bonpland has dried, with duplicates, more than ſix thouſand plants. I have deſcribed with him on the ſpot twelve hundred ſpecies, great part of which appeared to us to belong to genera not deſcribed by Aublet, Jacquin, Mutis, or Dombey. We have collected inſects, ſhells, and different kinds of wood proper for dyeing; we have diſſected crocodiles, lamantins, apes, and the gymnotus electricus, the fluid of which is abſolutely galvanic and not electric; and have deſcribed a great many ſerpents, lizards, and fiſh. I have made drawings of a great number of objects; in a word, I flatter myſelf that if I have erred it is rather through ignorance than want of activity. What enjoyment to live in the midſt of theſe riches of nature, ſo majeſtic and grand! Behold, then, the deareſt and moſt ardent of my wiſhes gratified! Amidſt the thick foreſts of the Rio-Nigro; ſurrounded by ferocious tygers and crocodiles; my body tormented with the ſtings of the formidable moſkitos and ants; having had for three months no other aliment than water, bananas, and manioc, among the Otomaqua Indians, who eat earth; or on the banks of the Caſquiara, under the equator, where, in the courſe of a hundred and thirty leagues, no human being is ſeen; — in all theſe embarraſſing ſituations I never repented of my undertakings: my ſufferings have been great, but they were only momentary. When I left Spain I intended to proceed directly to Mexico, thence to Peru and the Philippines; but a malignant fever, which broke out in our frigate, induced me to remain on this coaſt of South America; and, thinking it poſſible to penetrate thence into the interior, I undertook two journeys, one to the miſſions of the Chayma Indians of Paria, and the other to that vaſt country ſituated to the north of the river of the Amazons, between Popayan and the mountains of the French part of Guyana. We twice paſſed the grand cataracts of the Orenoquo, and thoſe of Atures and Maypura, in lat. 50° 12′ and long. 5° 39′, W. dep. from Paris 4° 43′ and 4° 41′ 40″. From the mouth of the Guaviara and the rivers Atabapo, Temi, and Tuamini, I cauſed my pirogua to be carried by land as far as the Rio-Nigro, while we followed on foot through foreſts of Hevea, Cinchona, and Canella Wintertona. I deſcended the Rio-Nigro as far as Saint Carlos that I might determine its longitude by Berthoud’s time-keeper, with which I am ſtill well ſatisfied. I aſcended the Caſquiara inhabited by the Ydapaminares, who eat nothing but ants dried in the ſmoke. I penetrated to the ſources of the Orenoquo, even beyond the volcano of Duida, or as far as the ferocity of the Guaica and Guaharribo Indians would permit me to venture, and I deſcended the whole of the Orenoquo, by the force of its current, as far as the capital of Guyana; performing a journey of 500 leagues in twenty-fix days, without counting thoſe on which we ſtopped. The error in the latitude (d’Anville’s chart) is more than two degrees, as it had never been determined by aſtronomical inſtruments. My health has withſtood all the fatigues of a journey of more than 1300 leagues; but my poor companion, C. Bonpland, had nearly fallen a victim to his zeal and devotion for the ſciences. After our return, he was attacked by a violent fever, accompanied with a dangerous vomiting; which, however, was ſpeedily cured. The river of the Amazons has been inhabited for 200 years by Europeans; but on the Orenoquo and the Rio- Nigro, it was only about thirty years ago that the Europeans ventured to form a few ſettlements beyond the cataracts. Thoſe which exiſt do not comprehend above 1800 Indians, from the eighth degree to the equator; and there are no other whites than ſix or ſeven miſſionary monks, who did every thing they could to facilitate our journey. From St. Thomas, the capital of Guyana, lat 8° 8′ 24″, long. 4° 25′ 2″, we croſſed once more the great deſert called Elanos, inhabited by wild cattle and horſes. I am now employed in conſtructing a map of the country through which I have travelled. I have been ſo fortunate as to make aſtronomical obſervations in fifty-four places. I obſerved at Caraccas, Cumana, and Tuy, twelve eclipſes of the ſatellites of Jupiter; an eclipſe of the ſun on the 28th of October 1799. By theſe means, and the chronometer, I flatter myſelf I ſhall be able to give a very exact map. We ſhall embark here at length for the Havannah, from which we ſhall proceed to Mexico. — Such is the ſummary of my travels. I know that you, Chaptal, Vauquelin, Guyton, are all intereſted in my fate; and for that reaſon I am not afraid of tiring you. We have ſcarcely any communication here with Europe. I have often attempted to write to you, as well as to our friends Vauquelin and Chaptal. I have ſent you ſome experiments on air, and the cauſe of miaſmata. I have ſent to Delambre and Lalande, extracts from my ſmall aſtronomical obſervations. Have any of theſe reached the place of their deſtination? By the conſul of the republic at Saint Thomas I tranſmitted to you the milk of a tree which the Indians call the cow, becauſe they drink this milky juice, which is not at all prejudicial, but exceedingly nouriſhing. By the help of the nitric acid I have made caoutchouc, and I mixed ſoda with that deſtined for you, according to the principles which you yourſelf fixed. In the month of January laſt we ſent, by the corvette Philippina, a collection of ſeeds for the Jardins des Plantes at Paris. We know they have arrived, and muſt have been delivered to citizens Juſſieu and Thoum by the ambaſſador of the republic at Madrid. By the flag of truce, which we expect here from Guadaloupe, the muſæum will receive other articles; for at preſent we muſt be fatisfied with preſenting you a few objects for your chemical analyſis. I have procured for you the curare, or celebrated poiſon of the Indians on the Rio-Nigro. I undertook a journey to Enneralda on purpoſe to ſee the liane, which produces this juice, but unfortunately we found it without flowers; and to ſee the method practiſed by the Catarapeni and Maquiritures Indians for making this poiſon. I ſhall give you, ſome other time, a more ample deſcription of it. I ſhall only add, that I ſend you the curare in a box of tin plate, and the branches of the plant maracury, which produces the poiſon. This liane grows, but not in great abundance, among the granitic mountains of Guandia and Yumariquin, under the ſhade of the theobromacacao and the caryocar. The Indians take off the epidermis and make an infuſion of it cold, having firſt expreſſed the juice; they then leave the water over the epidermis half expreſſed, and afterwards filter the infuſion. The filtered liquor is yellowiſh: it is then baked, and concentrated by evaporation and inſpiſſation to the conſiſtence of molaſſes. This matter contains already the poiſon, but not being ſufficiently thick to daub over the points of their arrows, they mix it with the glutinous juice of another tree, which they call kiracaguero. This mixture is again baked till the whole is reduced to a browniſh maſs. You know that the curare is taken internally as a ſtomachic: it is not noxious but when it comes into contact with the blood, which it deoxydates. It is only a few days ago that I began to make experiments upon it, and I have found that it decompoſes atmoſpheric air. I beg you will try to de-oxydate with it the metallic oxyds, and that you will examine whether the experiments of Fontana were properly made. This box, and the other articles announced here, have not yet reached C. Fourcroy. I add to the curare and the marecury, the dapitche, the leche de pindare, and the earth of the Otomaquas. The dapitche is a ſtate of the elaſtic gum, which, is, no doubt, unknown to you. We diſcovered it in a place where there is no hevea, in the marſhes of the mountain of Javita, lat. 2° 5′, which are ſamous on account of the terrible ſerpents, of the boa kind, found in them. Among the Pormiſano and Paragini Indians we ſaw muſical inſtruments made of the caoutehouc, and the inhabitants told us they found it in the earth. The dapitche or zapir is really a ſpongy white maſs found under the roots of two trees, which appeared to us of a new genus, the jacio and the curvana, and of which we ſhall one day give a deſcription. The juice of theſe trees is a very aqueous milk, but it appears that it is a malady in theſe trees to loſe the juice by the roots. This diſcharge cauſes the tree to periſh, and the milk coagulates in the moiſt earth, where it is preſerved from the contact of the air. I ſend you the dapitche itſelf, and a maſs of caoutchouc made from it, merely by expoſing it to heat or diſſolving it over the fire. This production, and the milk of the cow, in your hands, will ſerve to throw new light on this ſubſtance, ſo curious in a phyſiological point of view. The leche de pindare, which is the dried milk of a pindartree, is a natural white varniſh. The Indians cover their veſſels and tacuma with this milk when it is freſh. It dries ſpeedily, and forms a very beautiful varniſh; but, unfortunately, it becomes yellow when dried in a large maſs; and it is in this ſtate that I ſend it to you. In regard to the earth of the Otomaquas, I muſt obſerve that this nation, ſo hideous by the paintings which disfigure their bodies, when the Orenoquo is very high, and they can find no tortoiſes, for three months eat ſcarcely any thing but a kind of fat earth. There are ſome of them who eat a pound and a half of it per day. Some of the monks aſſert that they mix with it the fat of the tails of crocodiles: but this is falſe. We found among the Otomaquas ſtores of the pure earth which they eat: they give it no other preparation than that of burning it ſlightly, and rendering it moiſt. It appears to me aſtoniſhing that people can be robuſt and eat a pound and a half of earth daily, while we find that earth produces a very pernicious effect among children. My own experiments on earths and their properties, however, give me reaſon to ſuſpect that they may be nouriſhing; that is to ſay, that they may act by affinities. I add for the muſæum, becauſe it has fallen into my hands, the ſmoking inſtrument of the Otomaquas, and a ſhirt of the Piroas, a neighbouring nation. This ſmoking inſtrument is none of the ſmalleſt, as you will ſee. It is a kind of plate, on which they place the raſped and rotten fruit of a mimoſa, mixed with ſalt and a little quick-lime. The Otomaqua holds the plate in one hand and in the other the tube, the two ends of which enter his noſtrils, that he may inhale this ſtimulating tobacco. This inſtrument has a hiſtorical intereſt: it is common only to the Otomaquas and the Omeguas, two nations who at preſent are 300 leagues diſtant from each other, among whom Condamine ſaw it. It proves that the Omeguas, who, according to an old tradition, came from Guaviara, may be deſcended from the Otomaquas, and that the city of Manoa was ſeen by Phillip de Vure between Meta and Guaviara. Theſe facts are intereſting in regard to the origin of the fable of the Dorado. The ſhirt, which one of my people wore for a long time, is the bark of the tree called morima, without any preparation. You ſee that ſhirts grow upon trees in this country, and near the Dorado, where I found no mineral curioſities but talc and a little titanium. It has been impoſſible for us to arrange the ſeeds and plants of the Rio-Nigro deſtined for Thouin, Juſſieu, and Desfontaines, who will not altogether have forgotten me. We have very uncommon things; for example, new kinds of befaria, new genera of palms; all which we ſhall ſoon diſpatch, and be aſſured that we ſhall not loſe ſight of the intereſts of the muſæum. But alas! captain Baudin has ſet out, and we are here! This is very hard and diſtreſſing. We ſhall perhaps find him in the South Sea. I beg you will remember me to the reſpectable members of the National Inſtitute: my reſpects to Berthollet, Chaptal, Vauquelin, Guyton, Juſſieu, Desfontaines, Halley, Delambre, Laplace, Cuvier. In the letter which I ſend to Delambre I forgot an eclipſe, which I beg you will add to it. Immerſion of the 3d ſatellite on the 4th of October 1800, at Cumana, at 16 h. 59′ 36″ mean time. P. S. Repeat, I beg of you, my requeſt to the Board of Longitude for the Connoiſſances des Tems. I regret the death of general Deſaix. What a loſs to the republic and all mankind!