The electrometer gave no sign of electricity. As the storm gathered the blue of the sky changed to grey. The thermometer rose 3'C, as is usual in the Tropics, and a heavy rain fell. Being sufficiently adapted to the climate not to fear the effect of a tropical downpour we stayed on the shore to observe the electrometer. I held it more than twenty minutes in my hand, 6 feet above the ground. For several minutes the electric charge remained the same, and then I noticed that the electricity in the atmosphere was first positive, then nil, then negative. I have gone into these details on the electric charge in the atmosphere because newly arrived European travelers usually describe just their impressions of a tropical storm. In a country where the year is divided into two halves, the dry and the wet season, or as the Indians say in their expressive language, 'of sun and rain', it is interesting to follow meteorological phenomena as one season turns into the next.

After tobacco the most important product of the Cumanacoa valley is indigo, whose intense color makes it the equal of Guatemalan indigo. All the indigo factories that we visited are constructed along the same principles. Two vats, where the plants 'rot', are placed together. Each one measures 15 feet square and 2. feet deep. From these upper vats the liquid passes into beaters where the water-mill is placed. The axle-tree of the great wheel crosses the two beaters. It is nailed with ladles, fixed to long handles, for the beating. From another percolating vat the coloured starch passes to the drying-boxes, spread on planks of Brazil-wood on small wheels so that they can be pushed under a roof in case of sudden rain. These sloping and low roofs give the drying-boxes the appearance of hothouses from a distance. In the Cumanacoa valley the fermentation of the plant takes place amazingly quickly; usually it does not take longer than four or five hours. This can be attributed to the humidity and the absence of sun during the plant's development.

The look of the sky, the movement of electricity, and the downpour of the 28th March announced the start of the rainy season: we were still advised to go to San Fernando de Apure by San Francisco de Capanaparo, along the Sinaruco river and the San Antonio hato to the Otomac village recently founded on the banks of the Meta river, and to embark on the Orinoco a little above Carichana. This land road crosses an unhealthy, fever-ridden country. An old farmer, Don Francisco Sanchez, offered to lead us. His clothes revealed how simply people live in these far-off countries. He had made a fortune of 100, piastres yet he rode on horseback barefoot with large silver spurs. We knew from several weeks' experience how sad and monotonous the llanos are and so we chose the longer route along the Apure river to the Orinoco. We chose one of the long pirogues that the Spaniards call lanchas. A pilot and four Indians were sufficient to drive it. On the poop a cabin covered with corypha leaves was built in a few hours. It was so spacious that it could have held a table and benches. They used oxhides stretched and nailed to frames of Brazil-wood. I mention these minute details to prove that our life on the Apure river was very different from the time when we were reduced to the narrow Orinoco canoes. We packed the pirogue with provisions for a month. You find plenty of hens, eggs, bananas, cassava and cacao at San Fernando. The good Capuchin monk gave us sherry, oranges and tamarinds to make fresh juices. We could easily tell that a roof made of palm leaves would heat up excessively on the bed of a large river where we would be always exposed to the sun's perpendicular rays. The Indians relied less on our supplies than on their hooks and nets. We also brought some weapons along, whose use was common as far as the cataracts. Further south the extreme humidity prevents missionaries from using guns. The Apure river teems with fish, manatees (91) and turtles whose eggs are more nourishing than tasty. The river banks are full of birds, including the pauxi and guacharaca, that could be called the turkey and pheasant of this region. Their flesh seemed harder and less white than our European gallinaceous family as they use their muscles more. We did not forget to add to our provisions fishing tackle, firearms and a few casks of brandy to use as exchange with the Orinoco Indians.

Two main aims guided my travels, published as the Relation historique. I wanted to make known the countries I visited, and to collect those facts that helped elucidate the new science vaguely named the Natural History of the World, Theory of the Earth or Physical Geography. Of these two aims, the second seemed the more important. I was passionately keen on botany and certain aspects of zoology, and flattered myself that our researches might add some new species to those already known. However, rather than discovering new, isolated facts I preferred linking already known ones together. The discovery of a new genus seemed to me far less interesting than an observation on the geographical relations of plants, or the migration of social plants, and the heights that different plants reach on the peaks of the cordilleras.

We observed that fern trees are usually far rarer than palm trees. Nature has limited them to temperate, humid and shady places. They shun the direct rays of the sun and while the pumos, corypha of the steppes, and other American palms prefer the naked, burning plains these tree fern, which seen from afar look like palms, maintain the character and habits of cryptogams. They prefer solitary places, shade, humidity and damp. Sometimes you find them on the coast, but only when protected by thick shade.