Our stay in Carichana let us gather our strength. Bonpland was carrying the germs of a serious illness, and needed rest. But as the delta of the rivers Horeda and Paruasi is covered with dense vegetation he could not resist a long botanical excursion and soaked himself several times a day in the water. Fortunately in the missionary's house we were supplied with bread made from maize flour, and even milk.

May 10th. Overnight our canoe was loaded and we set off a little before dawn to go up the Río Negro to the mouth of the Casiquiare and begin our researches on the true course of this river linking the Orinoco and Amazon. The morning was beautiful, but as the heat rose the sky began to cloud over. The air is so saturated with water in these forests that water bubbles become visible at the slightest increase of evaporation on the earth's surface. As there is no breeze the humid strata are not replaced and renewed by drier air. This clouded sky made us gloomier and gloomier. Through this humidity Bonpland -lost the plants he had collected; for my part I feared finding the same Río Negro mists in the Casiquiare valley. For more than half a century nobody in the missions has doubted the existence of communications between the two great river systems: the important aim of our journey was reduced to fixing the course of the Casiquiare by astronomic means, especially at its point of entry into the Río Negro, and its bifurcation with the Orinoco. Without sun or stars this aim would have been frustrated, and we would have been uselessly exposed to long, weary deprivation. Our travelling companions wanted to return by the shortest journey, along the Pimichín and its small rivers; but Bonpland preferred, like myself, to persist in the original plan we had traced out while crossing the Great Cataracts. We had already traveled by canoe from San Fernando de Apure to San Carlos along the Apure, Orinoco, Atabapo, Temi, Tuamini and Río Negro for over 180 leagues. In entering the Orinoco by the Casiquiare we still had some 320 leagues to cover from San Carlos to Angostura. It would have been a shame to let ourselves be discouraged by the fear of a cloudy sky and the Casiquiare mosquitoes. Our Indian pilot, who had recently visited Mandavaca, promised us sun and 'those great stars that eat up clouds' once we had left the black waters of the Guaviare. So we managed to carry out our first plan and returned to San Fernando along the Casiquiare. Luckily for our researches the Indian's prediction was fulfilled. The white waters brought us a clear sky, stars, mosquitoes and crocodiles.

In the Pararuma camp we saw for the first time some live animals that we had only previously seen stuffed in European cabinets. Missionaries trade with these little animals. They exchange tobacco, a resin called mani, chica pigment, gallitos (cock-of-the-rocks), titi monkeys, capuchin monkeys, and other monkeys appreciated on the coast, for cloth, nails, axes, hooks and needles. These Orinoco animals are bought at disgustingly low prices from the Indians who live in the monks' missions. These same Indians then have to buy from the monks at very high prices what they need for fishing and farming with the money they get from the egg harvest. We bought various little animals, which travelled with us for the rest of our voyage up river, enabling us to study their way of life.

Another characteristic common to both the New Andalusian coast and Peru is the frequency of earthquakes and the limits nature seems to have prescribed for these phenomena. In Cumana we ourselves felt violent seismic shocks; they were still rebuilding the ruined houses and so we were able to gather detailed information on the spot about the terrible catastrophe of the 14th of December 1797. These notions will be the more interesting as earthquakes have been considered up to now less from a physical and geographical point of view than from the way they disastrously affect the population and well-being of society.

Leaving the tableland of Guardia we descended to the Indian village of Santa Cruz. First we reached a steep, extremely slippery slope that the missionaries strangely named Bajada del Purgatorio, or Descent of Purgatory. It consists of eroded slaty sandstone, covered with clay; the slope seems terribly steep. To go down, the mules draw their hind legs to their forelegs, lower their rumps and trust their luck sliding downhill. The rider has nothing to fear as long as he drops the reins and leaves the mule alone. From here to the left we saw the great pyramid of Guàcharo. This calcareous peak looks very picturesque, but we soon lost it to view when we entered the thick jungle known as Montana de Santa María. We spent seven hours crossing it. It is hard to imagine a worse path; a veritable ladder, a kind of gorge where, during the rainy season, torrent water rushes down the rocks step by step. The steps are from 2 to 3 feet high. The hapless animals first have to calculate how to pass their loads between the tree trunks, and then jump from one block to another. Scared of slipping they wait a few moments, as if studying the terrain, and then draw their four legs together like wild goats do. If the mule misses the nearest rock it sinks deep into the soft ochre clay that fills in the gaps between the rocks. When there are no rocks, the rider's feet and the mule's legs are supported by a tangle of enormous tree roots. The creoles have faith in the skill and instinct of their mules and remain in the saddle during the long dangerous descent. We preferred to dismount because we feared fatigue less than they do, and were more prepared to travel slowly as we never stopped collecting plants and examining the rocks.

The supposed gold mine of Cuchivano, which was the object of our trip, was nothing but a hole that had been cut in one of the strata of black marl, rich in pyrites. The marly stratum crosses the torrent and, as the water washes out metallic grains, the people imagine that the torrent carries gold because of the brilliancy of the pyrites. We were told that after the great earthquake of 1765 the Juagua river waters were so filled with gold that 'men came from great distances and unknown countries' to set up washing places on the spot. They disappeared over night, having collected masses of gold. Needless to add that this is a fable. Some direct experiments made with acids during my stay at Caracas proved that the Cuchivano pyrites are not at all auriferous. My disbelief upset our guides. However much I said and repeated that from the supposed gold mine the most that could be found was alum and sulphate of iron, they continued to gather secretly all the pyrite fragments they saw sparkling in the water. The fewer mines there are in a country, the more the inhabitants hold exaggerated ideas about how easily riches are extracted from the depths of the earth. How much time was lost during our five-year voyage exploring ravines, at the insistence of our hosts, where pyrite strata have for centuries been called by the pretentious name of minas de oro! We have smiled so often seeing men of all classes - magistrates, village priests, serious missionaries - all grinding amphibole or yellow mica with endless patience, desperate to extract gold by means of mercury! This rage for searching for mines amazed us in a climate where the earth needs only to be slightly raked in order to produce rich harvests.