The Sea in the Jungle

by N. J. BERRILL

1

THE German naturalist Alexander von Humboldt and the French botanist Aimé Bonpland sailed aboard a wooden ship, the Pizarro, and watched the Spanish coast fade out of sight, in June, 1799. As the nineteenth century approached, Humboldt crossed the Atlantic and stepped through the curtain Spain had drawn around her conquests for three hundred years, armed with a passport from Madrid.

In spite of war and revolution. Western thought was quickening, and physical and chemical science had found its feet. No one was more alerted to it than Humboldt, and no one ever made greater use of his information or carried more up-to-date equipment. He had thermometers and barometers, batteries and galvanometers, apparatus for gas analysis, astronomical instruments, and anatomists’ dissecting tools. It sounds more like a modern research laboratory, but it was the field equipment of one man intent on exploring a tropical rain forest and the peaks of the Andes; and for the most part the apparatus and knowledge were inventions and discoveries of the previous decade.

I do not believe that the first space ship destined for Mars in the coming millennium could represent more enterprise, courage, and preparedness than Humboldt bore as an individual a century and a half ago. He took into the richest parts of an almost unsullied earth all that was known of the universe in his time, and surveyed and analyzed all that came his way.

The passage to Teneriffe was uneventful except to a naturalist. Humboldt and Bonpland looked in vain for ocean weed but were startled at the abundance and variety of jellyfish — some blue, some yellow-brown, some purple, swarms that took an hour to pass the ship. North of the Cape Verde Islands they passed through great masses of floating weed and speculated about them. Floating weeds must have been torn from submarine rocks, possibly by fish and molluscs, and there is no suspicion that the weed vegetatively propagates free of any attachment and is as ancient an inhabitant of the open ocean as the flying fish itself. Yet it took more than another century for this to be recognized.

The ship avoided Trinidad, which the English had taken from Spain two years before, crossed the shoal between Tobago and Grenada, and turned south toward the American mainland. At daybreak, two days later, the mountains of New Andalusia, half veiled by mists, rose above the southern horizon, and the city and castle of Cumana appeared between groves of sixty-foot cocoa trees. The first weeks at Cumana were employed in testing instruments and in collecting and pressing the plants of the region. Before they returned to Europe, Bonpland was to have discovered six thousand plants new to science, which I suppose is not too surprising, considering that he was the first professional botanist to enter South America since Linnaeus first put botany on a systematic basis.

Travelers have always been inclined to underestimate the intelligence and natural curiosity of a community remote from what is thought to be the center of civilization. One of the most surprised persons I know was a botanist who visited the French-speaking black republic of Haiti and came back with the report that he had never in Europe or America met such an intellectually active and intellectually hungry group of men as the darkskinned scientists of Port-au-Prince.

Humboldt was no less startled and pleasantly excited with his reception by the Spanish colonists at Cumana and elsewhere. From Cumana the two naturalists went to Caracas, their real point of departure for their long journey into the heart of the continent.

Their route from Caracas took them south over the high Venezuelan plain to one of the northwestern tribularies of the Orinoco, alternately through dry stony country and rich woodland and forest and lakes. Even in 1800 Humboldt was already alarmed at the creeping consequence of forest destruction, of ensuing climatic change, lack of water and fuel — as sugar, indigo, and cotton replaced the great fig trees and mimosas of the lands around the lakes.

“From a peopled country embellished by cultivation,” wrote Humboldt, “we plunge into a vast solitude. Accustomed to the aspect of rocks, and to the shade of valleys, the traveller beholds with astonishment these Llanos or savannahs without trees, these immense plains, which seem to ascend to the horizon. ... In the rainy season they are covered with verdure, but in the time of great drought they assume the aspect of a desert. The grass is reduced to powder; the earth cracks; the alligators and great serpents remain buried in the dried mud till awakened from their long lethargy by the first showers of spring. . . . Often within a distance of thirty square leagues there is not an eminence more than a foot high. This resemblance to the surface of the sea strikes the imagination most powerfully where the plains are altogether destitute of palm trees, and where the mountains of the shore and of the Orinoco are so distant that they cannot be seen. . . . As we advanced into the southern part of the Llanos, we found the ground more dusty, more destitute of herbage, and more cracked by the effect of long drought.”

After nights spent in hammocks over which hovered enormous vampire bats, intent, it seemed, on fastening upon their faces, Humboldt and Bonpland arrived at San Fernando, the termination of the journey across the Llanos. Humboldt ceased to be the physiologist and became out right explorer.

2

SAN FERNANDO was a Capuchin missionary town newly established near the white sandy shores of the Apure River, one of the greater branches of the Orinoco. At the time of their arrival the dry season was about to end and the heat was terrific. In the wet season, they heard, the savannas of this region became covered with twelve or fourteen feet of water, and farms and villages then stood on shoals no more than two or three feet above the water. The Apure, Meta, and Orinoco all swell with the rains, overflowing into the great basin, and it was a common sight to see mares, followed by their colts, swimming to feed upon the tops of the grass waving above the water. The colts drowned everywhere, in large numbers, and even the mares survived only by virtue of longer legs and in spite of the crocodiles that pursued them. As the rivers return to their beds, the savanna is overspread with a beautiful scented grass.

A day or two of San Fernando was more than enough, although one of them was memorable. At sunrise one morning, with thunder rolling from all directions and the first rain of the season falling, long files of porpoises began to play along the surface of the Apure, to the alarm of the slow and indolent crocodiles who dived for the bottom whenever they came too close.

Humboldt, Bonpland, and the brother-in-law of the provincial governor, newly arrived from Cadiz, left San Fernando in a large Indian canoe so spacious that it carried a crew of four paddlers, a pilot, and a palm-thatched cabin containing a table and benches. They traveled down the Apure River to its junction with the Orinoco, with thorny jungle on either side, through which came jaguars, tapirs, and peccaries to drink. Crocodiles lay stretched on the sand between the river and the jungle, although with the rainy season hardly begun, hundreds still remained buried in the mud of the savannas.

Porpoises still plowed the river in long files, as out of place as a sailor in Denver; flocks of parakeets shrieked past, pursued by little whistling goshawks; and at one point the canoe passed a low island crowded with thousands of flamingos, rose-colored spoonbills, herons, and moor hens — so close together they seemed unable to stir. At night, on shore, a fire was lit — with difficulty, for the forest was impenetrable and dry wood hard to find. “Finding no trees on the strand, we stuck our oars in the ground, and to these fastened our hammocks. Everything passed tranquilly until eleven at night, and then a noise so terrific arose in the neighbouring forest that it was impossible to close our eyes. There were the liltle soft cries of the sapajons, the moans of the alouate monkeys, the howling of the jaguars and cougars, the peccary, and the sloth, the cries of the eurassow, the parakeets and other birds.” There was no silence in the forest at night, and long-tailed bats and sharp-nosed insects made disturbance doubly real.

During the last evening on the Apure the canoe passed the Cano del Manati, so named on account of the immense numbers of manatees caught there every year. Humboldt, saw them in all of the branches of the Orinoco and succeeded in dissecting one of these ten-foot, six-hundred-pound mermaids. Unlike those Columbus saw in the Caribbean, these showed no trace of nails on the edge of the fins, and were not so large. Otherwise a manatee is a manatee and looks like a mermaid or a sea cow according to your traditions and disposition: two species in the Americas, one in Africa, three in the East Indies if you include the dugong, and one, the largest of all, Steller’s sea cow, which used to frequent the shores of Bering Strait.

The manatee is easily caught, for it is a slowwitted vegetarian that relies more upon bulk than speed to avoid destruction, apart from a certain invisibility in the water resulting from a blotched and dusky color. It is a curious animal, streamlined and almost hairless, with only paddle-like fore limbs present. Not only are there no hind limbs but there is hardly a trace of the pelvis to which they were once attached. In their own way manatees are as aquatic, and as warm-blooded, as whales and porpoises, with a propelling tail blade that is vertical instead of horizontal. And like the whales they are full of oil and fat, called manatee butter, used in food and for lamps in the churches along the river. Even the Indians are perplexed, for they cannot understand why an animal living in water and resembling a fish should suckle its young. Humboldt and Bonpland, in. dissecting a manatee, were greatly impressed by the enormous length of the intestine — more than one hundred feet — and by the subdivision of the stomach into compartments, both features being typical of purely plant-eating mammals, especially those which chew the cud, which suggests something of the manatee’s ancestry.

Manatee butter troubles me. I have always assumed that the large amount of blubber and oil in porpoises and whales, seals and penguins, served primarily as insulation against loss of body heat. A seal lying on an ice-pan makes no impression ; its warmth is kept within and no ice melts. The fat of course is also an energy reserve, and its thickness in seals and whales changes with the seasons. Eskimos who use rifles instead of harpoons lose two out of every three seals that they shoot in summertime because the bodies sink so fast. But all this concerns warm-blooded meat-eating mammals and birds that have gone back to the sea for their livelihood.

Manatees and dugongs are not flesh eaters, however, but are confirmed vegetarians, and they venture to sea only on excursions along the shore for seaweed or to get from one river month to the next. There is little doubt that they came into being in great tropical rivers and estuaries where lush vegetation has always been plentiful, and at first were as quadrupedal as a tapir or hippopotamus is. Why it was so important to become streamlined as a swimmer is less clear, unless it was to avoid the crocodiles or to get weed at a greater depth than a regular four-legged creat ure could roach. If there is any truth in all this and manatees really are products of tropical fresh waters, why should they contain so much fat? It can’t be for warmth, and with a steady supply of food there is little need for reserves; it may have something to do with buoyancy in the water, or perhaps it is concerned with shape. If quick movement through water is important, it probably has been so from the beginning, and there are few animals so badly shaped for swimming as the average quadruped. The change to fishlike form is difficult and age-consuming, and the shortest route to a more streamlined shape is fat. Fat can be molded in far fewer generations than it takes for muscle and bone, and sleek contours may depend more upon the use of blubber than we think. After all, it has worked with the maid and should work for the mermaid; nature covered both with fat and patted it into shape. It’s an appealing thought, and is not as crazy as it sounds.

3

HUMBOLDT and his companions were about to sling their hammocks from the trunk of a locust tree near the Bay of Manatees, when a couple of large-spotted jaguars slunk out from behind it. So the travelers pushed on to a small island and in the day that followed found the Orinoco. The river stretched before them as an immense plain of water, with white-topped waves as far as the eye could reach. Instead of continuing downstream as on the Apure, they turned southwest along the shore, the fresh northeast breeze carrying them full sail up the Orinoco to the Boca de la Tortuga, an island celebrated for its turtle fishery.

Humboldt arrived at the critical moment, for the egg-laying of the turtles takes place at the very end of the dry season —and on the island were some white traders and more than three hundred natives, all assembled for the cosecha, the annual harvest of the eggs. A Franciscan monk stood by to supervise the proceedings; his chief duty was to select assistants to help determine the extent of the sand which contained eggs and to divide it among the various Indian families present. Two kinds of turtles laid their eggs along the beaches, fresh-water terrapins with feet neither stumpy like the tortoise nor flippers like the sea turtle, and more or less giants among their kind, forty or fifty pounds apiece. Just before the eggs are laid the turtles gather around the islands in unbelievable numbers and inspect the shore with an eye to safety, and then, for the most part between midnight and dawn, they stumble slowly to a site well above the water line and set to work — each to excavate pits two to three feet deep in which to lay about one hundred good-sized eggs. Only the females come ashore, but in such numbers that many dig their holes where eggs have already been laid.

Neither turtles nor Indians have changed very much, and as soon as a sand bar is divided the natives start excavating, each family digging with their hands until at the end of the second day they have a mound of eggs four or five feet high. Some are eaten then and there, others dried for future use, but most are squashed and poured with water into a wooden trough to bake in the sun until the oil comes to the top. This is skimmed off and boiled for use in cooking or for lamps, like the manatee butter. The amount of oil produced is the best indication of the number of turtles there must be in the South American river. Humboldt found that the three islands he encountered yielded about five thousand jars, that it, took five thousand eggs to fill a jar, and that a third of the eggs were broken when laid; so that the harvest consisted of more than thirty million eggs. At one hundred apiece, more than three hundred thousand females must have been busy laying them, and this could have been but an insignificant proportion of the total turtle population of the river systems. Above all else it is turtle territory and remains so to this day.

In spite of the egg harvesting, the turtles seem to be as abundant as ever, and this also in spite of the jaguars, crocodiles, herons, and vultures that feast on the babies as they struggle out of the nests onto the sand above. Though hatching may have occurred during the day, emergence above ground always takes place at night, which is just as well, for the temperature at the sand surface under the hot equatorial sun Humboldt found to be as high as 150° F. Young turtles attempting to reach the water during the day turned red, shriveled, and died before covering ten yards. Sometimes eggs are laid a mile away from the river, and it is a peculiar instinct that drives the newly hatched reptiles through the darkness toward the water, usually by the most direct route. Baby sea turtles have a blue horizon to aim at, but the fresh-water terrapins manage without such a guide, and leave us in wonder with no good answer. If they are picked up and turned around, they regain their right direction.

Humboldt and Bonpland left Turtle Island loaded with little live turtles and sun-dried eggs for the use of the native crew. The river here was nearly five miles across, though six hundred miles from its mouth. Gradually it narrowed and the current increased. High and wooded banks and gusty wind made sailing ever more difficult, but at last, after passing between the high cliffs of the Strait of Baraguan, they came to Pararuma, where the pilot informed them that that was as far as he and his boat could take them.

Even in the blazing heat of the noonday sun, when a thermometer placed against the rocks rose to 140° F., Humboldt felt the pulsing throb of nature: “all the stones were covered with an innumerable quantity of iguanas and geckos with spreading and membranous fingers. These lizards, motionless, with heads raised and mouths open, seemed to suck in the heated air. The soil appeared to undulate, from the effect of the mirage, without, a breath of wind being felt. The sun was near the zenith, and its dazzling light, reflected from the surface of the river, contrasted with the reddish vapours that enveloped every surrounding object.

. . . The beasts of the forest retire to the thickets; the birds hide themselves beneath the foliage of the trees, or in the crevices of the rocks. Yet amidst this apparent silence we hear a dull vibration, a continual murmur, a hum of insects filling all the lower strata of the air. . . . Myriads of insects creep upon tne soil, and flutter round the plants parched by the heat of the sun. A confused noise issues from every bush, from the decayed trunks of trees, from the clefts of rocks, and from the ground undermined by lizards, millipedes and worm-salamanders. All nature breathes, and under a thousand forms life is diffused throughout the cracked and dusty soil, in the waters, and in the air about us.“

Fortunately at Pararuma they were able to purchase a good canoe, and the missionary to the cataract country offered to go along with them as guide. “The new canoe intended for us was, like all Indian boats, a trunk of a tree hollowed out partly by the hatchet and partly by fire. It was forty feet long, and three broad. Three persons could not sit in it side by side. ... A sort of lattice work had been constructed on the stern with branches of trees. Unfortunately the roof of leaves was so low that we were obliged to lie down, without seeing anything, or, if seated, to sit nearly double. . . . The fore part of the boat was filled with Indian rowers, furnished with paddles, three feet long, in the form of spoons. They were all naked, seated two by two, and they kept time in rowing with a surprising uniformity, singing songs of a sad and monotonous character. The small cages containing our birds and monkeys, the number of which augmented as we advanced, were hung some to the branches and others to the bow of the boat. This was our travelling menagerie. . . . There remained no other place for the dried plants, trunks, a sextant, a dipping needle, and the meteorological instruments, than the space below the lattice work of branches, on which we were compelled to remain stretched the greater part of the day. To these inconveniences were joined the swarms of mosquitoes and the heat.”In this manner they made their way up the swelling Orinoco to Carichana.

Leaving Carichana the course of the river became more and more blocked by great granite rocks, until the channels grew so narrow that the canoe had to be warped along with ropes. The waters of the great Orinoco seemed almost to disappear among the piled rocky chaos, and even the crocodiles seemed to shun the noise of the cataracts. Later the canoe with its vulnerable and precarious freight reached the junction of the Orinoco with its tributary the Meta, itself the union of two rivers.

4

FROM the Meta onwards the journey up the Orinoco became increasingly one of paddling against, tumultuous waters, hauling between rocks, and portaging around cataracts, with so many tributaries joining in that it was difficult at last to say which was the Orinoco itself. Humboldt was not concerned with tracing the mighty river to its source, and in fact it is only within the last year that another expedition has pressed into the dank forest beyond the limit of Humboldt’s journey, supported by parachuted supplies, to measure the various streams of the Parima Mountains in an attempt to discover which is the largest. It is still one of the world’s last frontiers.

Humboldt’s objective was to confirm his belief in an old report that there was a navigable connection between the Amazon and the Orinoco. Instead of ascending the river directly to Esmeralda, the base of the recent expedition, he turned aside at San Fernando at the head of the great cataracts. “During the night, we had left, almost unperceived, the waters of the Orinoco; and at sunrise found ourselves as if transported to a new country, on the banks of a river the name of which we had scarcely ever heard pronounced and which was to conduct us, by the portage of Pimichin, to the Rio Negro, on the frontiers of Brazil."’ If it had not been for the Franciscan missions he would not have succeeded, and now that they are no more, travel in this region is much more difficult.

“You will go up,” said the president of the missions, who resided at San Fernando, “first the Atabapo, then the Temi, and finally the Tuamini. When the force of the current of ‘black waters’ hinders you from advancing, you will be conducted out of the bed of the river through forests, which you will find inundated. Two monks only are settled in those desert places, between the Orinoco and the Rio Negro; but at Javita you will be furnished with the means of having your canoe drawn over land in the course of four days to Cano Pimichin. If it be not broken to pieces you will descend the Rio Negro without any obstacle as far as the little fort of San Carlos; you will go up the Cusiquiare, and then return to San Fernando in a month, descending the Upper Orinoco.” Such was the plan and Humboldt carried it out in thirtythree days. From San Carlos he might have gone on down the Rio Negro into Portuguese territory, and so down the length of the Amazon.

Near the junction of the Temi and the Tuamini they left the bed of the river and proceeded in their canoe southward across the forest through channels four or five feet broad, in water rarely more than three feet deep. “An Indian furnished with a machete stood at the head of our boat, employed continually in chopping off the branches that crossed each other from the two sides of the channel. In the thickest part of the forest we were astonished by an extraordinary noise. On beating the bushes, a shoal of toninas or fresh water dolphins (porpoises) four feet long, surrounded our boat. They fled across the forest, throwing out those spouts of compressed air and water which have given them in every language, the name of “blowers.’ How singular was this spectacle in an inland spot, three or four hundred leagues from the mouths of the Orinoco and the Amazon!”

Humboldt was amazed, and no wonder. I can think of few animals more marine than a whale, whether or not the whale is small and goes by some other name; and few places on this earth seem more remote from the ocean than the flooded forest floor of a raised watershed a thousand miles from the sea. No simile comes to mind which can sharpen the contrast or the incongruity of tiny whales sporting in little more than knee-deep water beneath green and flowering vines in tropical jungle. Humboldt himself speculated on how they succeeded in reaching such remote territory, and favored a passage from the sea by the Amazon route, feeling that the Orinoco cataracts would have been too formidable a barrier.

Humboldt and Honplaud made the Pimichin portage through a snake-infested marsh with no more casualty than the loss of much of the botanist’s plant collection through excessive humidity, to come at last to the Rio Negro, the great tributary to the Amazon. In May they left the border fort of San Carlos, went up the Rio Negro to the mouth of the Casiquiare, and for ten days paddled against the current of that amazing little river, leaving black water for white, cloudy skies for starry nights and for more mosquitoes and crocodiles. When they reached the end of the Casiquiare and found themselves entering the Orinoco again, they had added to their already overcrowded canoe a toucan, seven parrots, “two manakins, a mot mot, two guans, two manavirois, eight monkeys and a short-tailed cacajao.” I am uncertain what animals some of these are, but the general effect under the circumstances is hard to imagine.

They re-entered the Orinoco about ten miles below the mission of Esmeralda, which they visited long enough to watch the Indian poison-master prepare curare, the deadly paralytic poison of arrow tips which is now an important drug, and to discover that you do not walk in the forests without a shield of very hard wood over head and shoulders, for this was he land of the Brazil nut, and the huge nut cases could kill a man if one fell on him. When at last they started downstream, the voyage was swift and it was a relief to leave a land to which monks were sent as a punishment, to be eaten alive by mosquitoes.