The road from San Fernando to Cumanacoa passes through small plantations in a humid, open valley. We forded numerous streams. In the shade the thermometer did not rise above 30°C, but we were exposed to the sun's rays because the bamboos along the path gave only a feeble shade and we suffered a lot from the heat. We passed through the village of Arenas, inhabited by Indians of the same race as those at San Fernando. But Arenas is no longer a mission, and the Indians, governed by a regular priest, are less naked and more civilized. Their church is known in the area for the primitive paintings on its walls. A narrow frieze encloses pictures of armadillos, caymans, jaguars and other New World animals.

Our first camp, above the Vasiva, was easily set up. We found a corner of dry land free from shrubs at the south of the cano Curamuni in a place where we saw capuchin monkeys, so easily identified with their black beards and sad, wild look, as they climbed along horizontal branches of a genipap. The next five nights became more and more uncomfortable as we approached the Orinoco bifurcation. The exuberance of the vegetation increases to such a point that it is hard to imagine, even when you have got used to the Tropics. There is no beach; a palisade of bunched trees becomes the river bank. You see a channel some 200 toises wide bordered with two enormous walls carpeted with leaves and liana. We tried to get ashore but could not even get out of the canoe. Sometimes at sunset we would follow the bank for an hour to reach, not a clearing, but a less overgrown patch where our Indians with their machetes could cut down enough to let thirteen or fourteen people camp. We could not spend the night in the pirogue. The mosquitoes that tormented us during the day crowded towards evening under the toldo, that is, the roof made of palm leaves that sheltered us from rain. Never were our hands or faces more swollen. Even father Zea, boasting that in his cataract missions he had the biggest and bravest (los más valientes) mosquitoes, agreed that these Casiquiare bites were the most painful he had ever felt. In the middle of thick jungle it was difficult to find any wood to light our fire; the branches are so full of sap in this equatorial region where it always rains that they hardly burn. Where there are no arid beaches we hardly ever came across that old wood which Indians say has been 'cooked in the sun'. A fire was only necessary to scare away jungle animals: we had such a low stock of food that we did not need wood to cook.