While on the spot I sketched a view (17) of the crater's interior edge as it is seen on the descent through the eastern wall's breach. Nothing is more striking than the superimposition of these lava strata, which reveals similar sinuosities to the calcareous rock of the Alps. These enormous ledges, sometimes horizontal and sometimes sloping or undulating, reminded us that long ago the entire mass had flowed, and that a combination of disruptive causes determined a particular flow. The Crest of the wall exhibits the same strange ramifications we find in coke. The northern edge is the highest. Towards the south-west the wall has considerably subsided and an enormous amount of scoria seems glued to the outer edge. On the west the rock is perforated, and through a wide opening you can see the sea and horizon. Perhaps the force of the steam broke through here just when the lava overflowed from the crater.

The fresh north-east wind blew us at full sail towards the boca de la tortuga. At eleven in the morning we landed on an island, which the Indians of the Uruana mission regard as their own, situated in the middle of the river. This island is famous for the fishing of turtles or, as is said here, the cosecha, or annual harvest of eggs. We found a group of Indians camping in palm-leaf huts. This camp-site had over 300 people in it. As we had been used, since San Fernando de Apure, to seeing only deserted beaches, we were struck by the bustle. Apart from Guamos and Otomacs, seen as two wild and untamed tribes, there were Caribs and other Indians from the Lower Orinoco. Each tribe camped separately, and could be recognized only by the different paints on their skins. We also found, among this noisy reunion, some white men, mainly pulperos, the small traders from Angostura, who had come upstream to buy turtle-egg oil from the Indians. The Uruana missionary, from Alcalà de Henares, came to meet us, extremely surprised to see us there. After inspecting our instruments, he exaggeratedly described the hardships we would suffer going further upstream beyond the cataracts. The purpose of our journey seemed very mysterious to him. 'How is anyone to believe, he said, 'that you left your homeland to come up this river to be eaten by mosquitoes and measure lands that do not belong to you? Luckily we were armed with recommendations from the guardian father of the Franciscan missions, while the brother-in-law of the Barinas governor accompanying us soon resolved the doubts that the whites there had about our dress, accent and arrival on the island. The missionary invited us to share a frugal meal of bananas and fish with him. He told us he had come to camp with the Indians during the harvesting of the eggs 'to celebrate open-air mass every day, to get oil for the lights in his church, and above all to govern this Republica de Indios y Castellanos where individuals wanted to profit selfishly with what God had given to everybody'.

After dividing all that belongs to astronomy, botany, zoology, the political description of New Spain, and the history of the ancient civilizations of certain New World nations into separate works, many general results and local descriptions remained left over, which I could still collect into separate treatises. I had prepared several during my journey; on races in South America; on the Orinoco missions; on what hinders civilization in the torrid zone, from the climate to the vegetation; the landscape of the Andes compared to the Swiss Alps; analogies between the rocks of the two continents; the air in the equinoctial regions, etc. I had left Europe with the firm decision not to write what is usually called the historical narrative of a journey, but just to publish the results of my researches. I had arranged the facts not as they presented themselves individually but in their relationships to each other. Surrounded by such powerful nature, and all the things seen every day, the traveler feels no inclination to record in a journal all the ordinary details of life that happen to him.

In the Orinoco the curare made from the raiz (root) is differentiated from that made from the bejuco (the liana or bark from branches). We saw only the latter prepared; the former is weaker and less sought after. On the Amazon we learned to identify poisons made by the Tikuna, Yagua, Pevas and Jibaros tribes, which, coming from the same plant, differ only due to more or less care spent in their elaboration. The Tikuna poison, made famous in Europe by M. de la Condamine, and which is becoming known as tikuna, is taken from a liana that grows on the Upper Maranon. This poison is partly due to the Tikuna Indians, who have remained independent in Spanish territory, and partly to Indians of the same tribe in missions. As poisons are indispensable to hunters in this climate, the Orinoco and Amazon missionaries have not interfered with their production. The poisons just named are completely different from those made by the Peca, the Lamas and Moyobambas. I convey such details because the fragments of plants that we examined have proved (contrary to common opinion) that the three poisons of the Tikuna, Peca and Moyobambas do not come from the same species, not even the same family. just as curare is simple in its composition, so the fabrication of the Moyobamba poison is long and complicated. You mix the sap of the bejuco de ambihuasca, the main ingredient, with pepper (capsicum), tobacco, barbasco (Jacquinia armillaris), sanango (Tabernae montana) and the milk of some apocyneae. The fresh sap of the ambihuasca is poisonous if it touches blood; the sap of the mavacure is deadly only when it is concentrated by heating, and boiling eliminates the poison from the root of the Jatropha manihot (Yucca amarca). When I rubbed the liana, which gives the cruel poison of the Peca, for a long time between my fingers on a very hot day, my hands became numb.

Mixed with the aromatic smells given off by the flowers, fruit and even wood there was something of our misty autumn forests. Among the majestic trees that reach 120 to 130 feet high our guides pointed out the curucay, which yields a whitish, liquid resin with a strong odor. The Cumanagoto and Tagire Indians used to burn it before their idols as incense. The young branches have an agreeable taste, though somewhat acid. Apart from the curucay and the enormous trunks of the hymenaea, from 9 to so feet in diameter, we noticed, above all others, the dragon (Croton sangulfluum), whose dark purple resin flows from its white bark; as well as the medicinal calahuala fern, and the irasse, macanilla, corozo and praga palm trees. This latter gives a tasty 'heart of palm' that we sometimes ate at the Caripe convent. These palm trees with pinnate and thorny leaves contrast pleasingly with the tree ferns. In the Caripe valley we discovered five new species of tree fern, while in Linnaeus's time botanists had not even found four in both continents.

A grass from Switzerland grows on the granite rocks of the Magellan Strait. (74) New Holland contains more than forty European phanerogamous plants. The greater amount of these plants, found equally in the temperate zones of both hemispheres, are completely absent in the intermediary or equinoctial regions, on plains and on mountains. A hairy-leafed violet, which signifies the last of the phanerogamous plants on Tenerife, and long thought specific to that island, can be seen 300 leagues further north near the snowy Pyrenean peaks. Grasses and sedges of Germany, Arabia and Senegal have been recognized among plants collected by Bonpland and myself on the cold Mexican tablelands, on the burning Orinoco banks and on the Andes, and at Quito in the Southern hemisphere. How can one believe that plants migrate over regions covered by sea? How have the germs of life, identical in appearance and in internal structure, developed at unequal distances from the poles and from the oceans, in places that share similar temperatures? Despite the influence of air pressure on the plants' vital functions, and despite the greater or lesser degree of light, it is heat, unequally distributed in different seasons, that must be considered vegetation's most powerful stimulus.