Digitale Ausgabe

New Barcelona, Nov. 24, 1800. DURING my ſtay in South America I diſpatched ſeveralletters to you and Lalande; I know you are intereſted in myfate, and I never let ſlip an opportunity of writing to you,though I have ſcarcely any hopes of my letters reaching theplace of their deſtination. I am now on the point of ſettingout for the Havannah and Mexico, after having performeda tour of thirteen hundred nautical leagues in this part of the New World, ſituated between Popayan, Quito, and Cayenne.I have ſlept for three months in the open air, in the woods,ſurrounded by tigers and hideous ſerpents, or on plains co-vered with crocodiles. Bananas, rice, and manioc, havebeen our ſole nouriſhment; for all proviſions ſoon becomeputrid in this damp and ſcorching country. How grand and majeſtic is nature among theſe mountains!From Baraquan and Uruana, which unknown nations havecovered with hieroglyphics, as far as the volcano of Duida,at the diſtance of ſixty leagues from the ſmall lake of Dorado,the elevation of which I have found to be 2176 metres, thereis only one cordillera of granite, that deſcends from Quito, |366| and proceeds from weſt to eaſt to join the mountains of theFrench part of Guyana. What variety among the Indianraces! All free, all governing themſelves and eating eachother, from the Guaicas of Gehetta, a pigmy nation, thelargeſt of whom are about four feet two inches in height, tothe white Guajaribos, who have really the whiteneſs of Eu-ropeans; from the Otomacos, who eat a pound and a halfof earth per day, to the Marivitanos and the Magueritares,who feed on ants and reſin. Having already ſpoken of alltheſe in a letter*, which I diſpatched from the mouths ofthe Orenoquo to our good friend Pommard, I ſhall confinemyſelf at preſent to a few aſtronomical obſervations, which,I think, I have made with a conſiderable degree of care. My time-keeper, by Berthoud, continues to go with greatcorrectneſs. I regulate it every four, five, or ſix days, by cor-reſponding altitudes, taken with my inſtruments, which donot err a ſecond; viz. ſextants by Ramſden and Troughton,a quadrant by Bird, and a horizon by Carroché. You knowthat I am not very learned in the mathematics, and that aſtro-nomy is not the object of my travels; yet with zeal and ap-plication, and by daily handling the ſame inſtruments, Ihave been able to do ſomething, and to do it better. As Itraverſed a country never viſited by Europeans till about thirtyyears ago, in which all the Chriſtian miſſions do not amountto 1800 ſouls, and conſequently where no one has ever yetbeen able to make obſervations, I conceived that I ought notto neglect ſo favourable an opportunity of enlarging our geo-graphical knowledge. You would have laughed had you ſeenme amidſt the Ydapamianeres Indians in the foreſt of Caſqui-ara, with my inſtruments mounted on boxes or trunks, whilethe ſhells of tortoiſes ſerved us as ſtools. Eight or nine apes,which we carried with us, had a ſtrong deſire to handle myhygrometers, barometers, and electrometers alſo: around alltheſe ten or twelve Indians ſtretched out in their hammocks,together with fires to ſecure us from the tigers, which are noleſs ferocious here than in Africa. The want of nouriſh-ment, the moſquitoes, the ants; the chigers, which enterthe ſkin and plough up the fleſh; the deſire of cooling our-

---

* This letter, when this was publiſhed, had not reached France|367| ſelves in the water, and the impoſſibility of doing it on ac-count of the ferocity of the caymans, the danger of beingpricked by the rajas and the teeth of the ſmall carib-fiſh—youth and a great deal of reſignation are required toendure all theſe. The evil is paſſed, and I have reapedmore than I durſt venture to hope. It is believed (ſee the map of father Caulin, the beſt ex-tant, though all the names are wrong,) that the Spaniſh poſ-ſeſſions of Guyana extend to the equator. But I have found,by very good obſervations of the ſtars called the Croſs andCanopus, which I made among the rocks of Culimacari,that San Carlos del Rio Negro, the moſt ſouthern eſtabliſh-ment, is in 1° 53′ of north latitude; and that the line paſſesthrough the government of Great Para, near St. Gabriel-de-las-Cachuellas, where there is a cataract, but not ſo conſi-derable as the two famous ones of Atures and Maypura. At Cumana, before the earthquake, which we experiencedon the 4th of November 1799, the magnetic inclination,meaſured with Borda’s compaſs, was found to be 44° 20′ ofthe new diviſion: after the earthquake it was 43° 35′; theneedle made 229 oſcillations in the courſe of ten minutes.Experiments have proved that the magnetic charge haschanged in this part of the world, and not in the needle. At Calabozo, in the centre of Uana, lat. 8° 56′ 56″, long.from Paris 44° 40′ 18″, the inclination was 39° 30′: numberof oſcillations 222. At Atures, one of the cataracts of the Orenoquo, in lat.5° 39′, long. 44° 42′ 19″, the inclination was 32° 85′: num-ber of oſcillations 221. At St. Fernando d’Atabapo, a miſſion at the mouth of theGuaviara, lat. 4° 9′ 50″, the inclination was 30° 30′: num-ber of oſcillations 219. At St. Carlos de Rio Negro, lat. 1° 53′, the inclinationwas 23° 20: number of oſcillations 216. According to the rules given by Meſſrs. Cavendiſh and Dalrymple, care was always taken, while obſerving, to turnthe compaſs to the eaſt and weſt to find the mean inclina-tions, and to correct the error which takes place when theaxis of the needle does not paſs exactly through its two points. |368| During this journey, which laſted a year, I determined54 points of South America, in which I obſerved the lati-tudes and longitudes: the former deduced, for the moſt part,from the meridian altitude of two ſtars at leaſt; and the lat-ter, either from the diſtances of the moon from the ſun andſtars, or from the time-keeper and horary angles. I am nowemployed in conſtructing a map of the country through whichI have travelled; and as my obſervations fill up the vacuumfound in the maps between Quito and Cayenne, to the northof the river of the Amazons, I flatter myſelf that they willbe intereſting to geographers. My time-keepers have not given me with exactneſs, butthe differences of meridian between the places of my departureand the Caraccas, Cumana, and St. Thomas de Nueva-Guay-anna, lat. 8° 8′ 24″, long. 21 of time, eaſt from Cumana.I am very anxious, therefore, on account of my map, to fixthe poſition of theſe three places in regard to Paris, and byobſervations purely aſtronomical. Beſides, it is very neceſ-ſary that navigators ſhould be able, at the time of their ar-rival on this coaſt, to find the longitude of the ports well de-termined, that they may know the ſtate of their chronome-ters; for, except Martinico, Guadaloupe, Portorico, whereM. De Churucca obſerved; Cayenne, and Quito, there arevery few places the longitude of which can be depended on;eſpecially in Spaniſh America. Carthagena, according tothe Connoiſſance des Temps, is at 5 h. 12′ 12″. But thethree emerſions of the ſatellites, obſerved by Herrera, all give69° 24′ 10″ weſt of Cadiz, or 5 h. 13′ 11″ to the weſt of Paris. I obſerved, with a teleſcope of Dollond, which magnifies95 times, at Cumana, in lat. 10° 27′ 37″: The immerſion of the ſecond ſatellite Nov. 7, 1799, at11 h. 41′ 18′ true time. Of the ſecond ſatellite, Sept. 11, at 16 h. 31′ 0″ true time. Of the firſt ſatellite, Sept. 25, 1800, at 17 h. 10′ 21″ meantime. The emerſion of the 4th ſatellite, Sept. 26, at 17 h. 28′ 0″mean time. Of the third ſatellite, Sept. 27, at 16 h. 25′ 55″ mean time. Of the fourth ſatellite, Sept. 26, at 17 h. 28′ 0″ mean time. |369| I am therefore miſtruſtful of the longitude of Cumana, asgiven me by my time-keeper. When I arrived from the Cana-ries at the Continent, I found the longitude to be 4 h. 26′ 4″;and the obſervations of M. Fidalgo, who obſerved emerſionsat Trinidad, but not at Cumana, give ſtill more; viz. 4 h.26′ 16″. Fidalgo found Trinidad 55° 16′ 32″ to the weſt ofCadiz, and Cumana 2° 41′ 25″ to the weſt of Puerta Eſpan̄a.But the map of Trinidad, publiſhed at London, from theexcellent obſervations of M. De Charucca, makes PuertaEſpan̄a 61° 22′ weſt from London. I am of opinion, there-fore, that, in conſtructing the map, the authors had beforethem the calculations by Lalande of the occultation of Alde-baran, obſerved at Porto Rico on the 21ſt of October 1793;for the capital of Porto Rico is by the time-keepers 4° 34 tothe weſt of Puerta Eſpan̄a, calculating the longitude by thatof Porto Rico 63° 48 15″; and for Cumana 66° 29′ 40″ tothe weſt of Paris. The five eclipſes of the ſatellites which Iſend you, muſt throw light on this ſubject; and, in my opi-nion, the longitude of Cumana will not be much beyond4 h. 25′ 20″. Unfortunately, the eclipſe of the ſun, whichI completely obſerved on the 28th of September at Cumana,making the horns paſs along the horizontal and vertical wires,was not viſible in Europe. I obſerved the end at 8 h. 14′ 22″mean time; the time certain to 1″ nearly, having taken cor-reſponding heights the ſame day. At Carras (Plaza della S. Trinidad) lat. 10° 31′ 4″, I ob-ſerved: The immerſion of the firſt ſatellite, Dec. 7, 1799, at 16 h.11′ 57″ true time. Of the third ſatellite, Dec. 7, at 17 h. 11′ 36″ true time. The emerſion of the firſt ſatellite, Jan. 17, 1800, at 11 h.14′ 8″ mean time. Of the ſecond ſatellite, Jan. 28, at 7 h. 58′ 8″ mean time. Of the fourth ſatellite, Jan. 18, at 8 h. 13′ 3′ mean time. At the Valle del Tuy al Pic della Cocuiza, lat. 10° 17′ 23″. The emerſion of the firſt ſatellite, Feb. 9, 1800, at 11 h.26′ 57″ mean time. Of the third ſatellite on the 10th of February, at 7 h. 58′50″ mean time. |370| But theſe laſt eclipſes were obſerved with a teleſcope of Caroché, which, though a very good one, magnifies only 58times, not being able to carry along with me, to Rio-Negro,the large teleſcope by Dollond. Declination of the magnetic needle at Cumana on the 27thof October 4° 13′ 45″; at Caraccas, 4° 38′ 45″; at Cala-bozo, 4° 54′ of the old diviſion. The port of La Guayra is exactly 29″ in time weſt fromCaraccas; and I hope that, by giving immerſions and emer-ſions, the meridian of Caraccas will be properly fixed. I have deſcribed, with Bonpland, more than 1200 plants*.