Part 13

We had been camped close to the river, where the trail that follows the telegraph line crosses it by a rough bridge. As our laden dugouts swung into the stream, Amilcar and Miller and all the others of the Gy-Parana party were on the banks and the bridge to wave farewell and wish us good-by and good luck. It was the height of the rainy season, and the swollen torrent was swift and brown. Our camp was at about 12 degrees 1 minute latitude south and 60 degrees 15 minutes longitude west of Greenwich. Our general course was to be northward toward the equator, by waterway through the vast forest.

We had seven canoes, all of them dugouts. One was small, one was cranky, and two were old, waterlogged, and leaky. The other three were good. The two old canoes were lashed together, and the cranky one was lashed to one of the others. Kermit with two paddlers went in the smallest of the good canoes; Colonel Rondon and Lyra with three other paddlers in the next largest; and the doctor, Cherrie, and I in the largest with three paddlers. The remaining eight camaradas--there were sixteen in all--were equally divided between our two pairs of lashed canoes. Although our personal baggage was cut down to the limit necessary for health and efficiency, yet on such a trip as ours, where scientific work has to be done and where food for twenty-two men for an unknown period of time has to be carried, it is impossible not to take a good deal of stuff; and the seven dugouts were too heavily laden.

The paddlers were a strapping set. They were expert rivermen and men of the forest, skilled veterans in wilderness work. They were lithe as panthers and brawny as bears. They swam like waterdogs. They were equally at home with pole and paddle, with axe and machete; and one was a good cook and others were good men around camp. They looked like pirates in the pictures of Howard Pyle or Maxfield Parrish; one or two of them were pirates, and one worse than a pirate; but most of them were hard-working, willing, and cheerful. They were white,--or, rather, the olive of southern Europe,--black, copper-colored, and of all intermediate shades. In my canoe Luiz the steersman, the headman, was a Matto Grosso negro; Julio the bowsman was from Bahia and of pure Portuguese blood; and the third man, Antonio, was a Parecis Indian.

The actual surveying of the river was done by Colonel Rondon and Lyra, with Kermit as their assistant. Kermit went first in his little canoe with the sighting-rod, on which two disks, one red and one white, were placed a metre apart. He selected a place which commanded as long vistas as possible up-stream and down, and which therefore might be at the angle of a bend; landed; cut away the branches which obstructed the view; and set up the sighting-pole--incidentally encountering maribundi wasps and swarms of biting and stinging ants. Lyra, from his station up-stream, with his telemetre established the distance, while Colonel Rondon with the compass took the direction, and made the records. Then they moved on to the point Kermit had left, and Kermit established a new point within their sight. The first half-day's work was slow. The general course of the stream was a trifle east of north, but at short intervals it bent and curved literally toward every point of the compass. Kermit landed nearly a hundred times, and we made but nine and a third kilometres.

My canoe ran ahead of the surveying canoes. The height of the water made the going easy, for most of the snags and fallen trees were well beneath the surface. Now and then, however, the swift water hurried us toward ripples that marked ugly spikes of sunken timber, or toward uprooted trees that stretched almost across the stream. Then the muscles stood out on the backs and arms of the paddlers as stroke on stroke they urged us away from and past the obstacle. If the leaning or fallen trees were the thorny, slender-stemmed boritana palms, which love the wet, they were often, although plunged beneath the river, in full and vigorous growth, their stems curving upward, and their frond- crowned tops shaken by the rushing water. It was interesting work, for no civilized man, no white man, had ever gone down or up this river or seen the country through which we were passing. The lofty and matted forest rose like a green wall on either hand. The trees were stately and beautiful. The looped and twisted vines hung from them like great ropes. Masses of epiphytes grew both on the dead trees and the living; some had huge leaves like elephants' ears. Now and then fragrant scents were blown to us from flowers on the banks. There were not many birds, and for the most part the forest was silent; rarely we heard strange calls from the depths of the woods, or saw a cormorant or ibis.

My canoe ran only a couple of hours. Then we halted to wait for the others. After a couple of hours more, as the surveyors had not turned up, we landed and made camp at a spot where the bank rose sharply for a hundred yards to a level stretch of ground. Our canoes were moored to trees. The axemen cleared a space for the tents; they were pitched, the baggage was brought up, and fires were kindled. The woods were almost soundless. Through them ran old tapir trails, but there was no fresh sign. Before nightfall the surveyors arrived. There were a few piums and gnats, and a few mosquitoes after dark, but not enough to make us uncomfortable. The small stingless bees, of slightly aromatic odor, swarmed while daylight lasted and crawled over our faces and hands; they were such tame, harmless little things that when they tickled too much I always tried to brush them away without hurting them. But they became a great nuisance after a while. It had been raining at intervals, and the weather was overcast; but after the sun went down the sky cleared. The stars were brilliant overhead, and the new moon hung in the west. It was a pleasant night, the air almost cool, and we slept soundly.

Next morning the two surveying canoes left immediately after breakfast. An hour later the two pairs of lashed canoes pushed off. I kept our canoe to let Cherrie collect, for in the early hours we could hear a number of birds in the woods near by. The most interesting birds he shot were a cotinga, brilliant turquoise-blue with a magenta- purple throat, and a big woodpecker, black above and cinnamon below with an entirely red head and neck. It was almost noon before we started. We saw a few more birds; there were fresh tapir and paca tracks at one point where we landed; once we heard howler monkeys from the depth of the forest, and once we saw a big otter in midstream. As we drifted and paddled down the swirling brown current, through the vivid rain-drenched green of the tropic forest, the trees leaned over the river from both banks. When those that had fallen in the river at some narrow point were very tall, or where it happened that two fell opposite each other, they formed barriers which the men in the leading canoes cleared with their axes. There were many palms, both the burity with its stiff fronds like enormous fans, and a handsome species of bacaba, with very long, gracefully curving fronds. In places the palms stood close together, towering and slender, their stems a stately colonnade, their fronds an arched fretwork against the sky. Butterflies of many hues fluttered over the river. The day was overcast, with showers of rain. When the sun broke through rifts in the clouds, his shafts turned the forest to gold.

In mid-afternoon we came to the mouth of a big and swift affluent entering from the right. It was undoubtedly the Bandeira, which we had crossed well toward its head, some ten days before, on our road to Bonofacio. The Nhambiquaras had then told Colonel Rondon that it flowed into the Duvida. After its junction, with the added volume of water, the river widened without losing its depth. It was so high that it had overflowed and stood among the trees on the lower levels. Only the higher stretches were dry. On the sheer banks where we landed we had to push the canoes for yards or rods through the branches of the submerged trees, hacking and hewing. There were occasional bays and ox-bows from which the current had shifted. In these the coarse marsh grass grew tall.

This evening we made camp on a flat of dry ground, densely wooded, of course, directly on the edge of the river and five feet above it. It was fine to see the speed and sinewy ease with which the choppers cleared an open space for the tents. Next morning, when we bathed before sunrise, we dived into deep water right from the shore, and from the moored canoes. This second day we made sixteen and a half kilometres along the course of the river, and nine kilometres in a straight line almost due north.

The following day, March 1, there was much rain--sometimes showers, sometimes vertical sheets of water. Our course was somewhat west of north and we made twenty and a half kilometres. We passed signs of Indian habitation. There were abandoned palm-leaf shelters on both banks. On the left bank we came to two or three old Indian fields, grown up with coarse fern and studded with the burned skeletons of trees. At the mouth of a brook which entered from the right some sticks stood in the water, marking the site of an old fish-trap. At one point we found the tough vine hand-rail of an Indian bridge running right across the river, a couple of feet above it. Evidently the bridge had been built at low water. Three stout poles had been driven into the stream-bed in a line at right angles to the current. The bridge had consisted of poles fastened to these supports, leading between them and from the support at each end to the banks. The rope of tough vines had been stretched as a hand-rail, necessary with such precarious footing. The rise of the river had swept away the bridge, but the props and the rope hand-rail remained. In the afternoon, from the boat, Cherrie shot a large dark-gray monkey with a prehensile tail. It was very good eating.

We camped on a dry level space, but a few feet above, and close beside, the river--so that our swimming-bath was handy. The trees were cleared and camp was made with orderly hurry. One of the men almost stepped on a poisonous coral-snake, which would have been a serious thing, as his feet were bare. But I had on stout shoes, and the fangs of these serpents--unlike those of the pit-vipers--are too short to penetrate good leather. I promptly put my foot on him, and he bit my shoe with harmless venom. It has been said that the brilliant hues of the coral-snake when in its native haunts really confer on it a concealing coloration. In the dark and tangled woods, and to an only less extent in the ordinary varied landscape, anything motionless, especially if partially hidden, easily eludes the eye. But against the dark-brown mould of the forest floor on which we found this coral- snake its bright and varied coloration was distinctly revealing; infinitely more so than the duller mottling of the jararaca and other dangerous snakes of the genus lachecis. In the same place, however, we found a striking example of genuine protective or mimetic coloration and shape. A rather large insect larva--at least we judged it to be a larval form, but we were none of us entomologists--bore a resemblance to a partially curled dry leaf which was fairly startling. The tail exactly resembled the stem or continuation of the midrib of the dead leaf. The flattened body was curled up at the sides, and veined and colored precisely like the leaf. The head, colored like the leaf, projected in front.

We were still in the Brazilian highlands. The forest did not teem with life. It was generally rather silent; we did not hear such a chorus of birds and mammals as we had occasionally heard even on our overland journey, when more than once we had been awakened at dawn by the howling, screaming, yelping, and chattering of monkeys, toucans, macaws, parrots, and parakeets. There were, however, from time to time, queer sounds from the forest, and after nightfall different kinds of frogs and insects uttered strange cries and calls. In volume and frequency these seemed to increase until midnight. Then they died away and before dawn everything was silent.

At this camp the carregadores ants completely devoured the doctor's undershirt, and ate holes in his mosquito-net; and they also ate the strap of Lyra's gun-case. The little stingless bees, of many kinds, swarmed in such multitudes, and were so persevering, that we had to wear our head-nets when we wrote or skinned specimens.

The following day was almost without rain. It was delightful to drift and paddle slowly down the beautiful tropical river. Until mid- afternoon the current was not very fast, and the broad, deep, placid stream bent and curved in every direction, although the general course was northwest. The country was flat, and more of the land was under than above water. Continually we found ourselves travelling between stretches of marshy forest where for miles the water stood or ran among the trees. Once we passed a hillock. We saw brilliantly colored parakeets and trogons. At last the slow current quickened. Faster it went, and faster, until it began to run like a mill-race, and we heard the roar of rapids ahead. We pulled to the right bank, moored the canoes, and while most of the men pitched camp two or three of them accompanied us to examine the rapids. We had made twenty kilometres.

We soon found that the rapids were a serious obstacle. There were many curls, and one or two regular falls, perhaps six feet high. It would have been impossible to run them, and they stretched for nearly a mile. The carry, however, which led through woods and over rocks in a nearly straight line, was somewhat shorter. It was not an easy portage over which to carry heavy loads and drag heavy dugout canoes. At the point where the descent was steepest there were great naked flats of friable sandstone and conglomerate. Over parts of these, where there was a surface of fine sand, there was a growth of coarse grass. Other parts were bare and had been worn by the weather into fantastic shapes--one projection looked like an old-fashioned beaver hat upside down. In this place, where the naked flats of rock showed the projection of the ledge through which the river had cut its course, the torrent rushed down a deep, sheer-sided, and extremely narrow channel. At one point it was less than two yards across, and for quite a distance not more than five or six yards. Yet only a mile or two above the rapids the deep, placid river was at least a hundred yards wide. It seemed extraordinary, almost impossible, that so broad a river could in so short a space of time contract its dimensions to the width of the strangled channel through which it now poured its entire volume.

This has for long been a station where the Nhambiquaras at intervals built their ephemeral villages and tilled the soil with the rude and destructive cultivation of savages. There were several abandoned old fields, where the dense growth of rank fern hid the tangle of burnt and fallen logs. Nor had the Nhambiquaras been long absent. In one trail we found what gypsies would have called a "pateran," a couple of branches arranged crosswise, eight leaves to a branch; it had some special significance, belonging to that class of signals, each with some peculiar and often complicated meaning, which are commonly used by many wild peoples. The Indians had thrown a simple bridge, consisting of four long poles, without a hand-rail, across one of the narrowest parts of the rock gorge through which the river foamed in its rapid descent. This sub-tribe of Indians was called the Navaite; we named the rapids after them, Navaite Rapids. By observation Lyra found them to be (in close approximation to) latitude 11 degrees 44 minutes south and longitude 60 degrees 18 minutes west from Greenwich.

We spent March 3 and 4 and the morning of the 5th in portaging around the rapids. The first night we camped in the forest beside the spot where we had halted. Next morning we moved the baggage to the foot of the rapids, where we intended to launch the canoes, and pitched our tents on the open sandstone flat. It rained heavily. The little bees were in such swarms as to be a nuisance. Many small stinging bees were with them, which stung badly. We were bitten by huge horse-flies, the size of bumblebees. More serious annoyance was caused by the pium and boroshuda flies during the hours of daylight, and by the polvora, the sand-flies, after dark. There were a few mosquitoes. The boroshudas were the worst pests; they brought the blood at once, and left marks that lasted for weeks. I did my writing in head-net and gauntlets. Fortunately we had with us several bottles of "fly dope"--so named on the label--put up, with the rest of our medicine, by Doctor Alexander Lambert; he had tested it in the north woods and found it excellent. I had never before been forced to use such an ointment, and had been reluctant to take it with me; but now I was glad enough to have it, and we all of us found it exceedingly useful. I would never again go into mosquito or sand-fly country without it. The effect of an application wears off after half an hour or so, and under many conditions, as when one is perspiring freely, it is of no use; but there are times when minute mosquitoes and gnats get through head-nets and under mosquito-bars, and when the ointments occasionally renewed may permit one to get sleep or rest which would otherwise be impossible of attainment. The termites got into our tent on the sand- flat, ate holes in Cherrie's mosquito-net and poncho, and were starting to work at our duffel-bags, when we discovered them.

Packing the loads across was simple. Dragging the heavy dugouts was labor. The biggest of the two water-logged ones was the heaviest. Lyra and Kermit did the job. All the men were employed at it except the cook, and one man who was down with fever. A road was chopped through the forest and a couple of hundred stout six-foot poles, or small logs, were cut as rollers and placed about two yards apart. With block and tackle the seven dugouts were hoisted out of the river up the steep banks, and up the rise of ground until the level was reached. Then the men harnessed themselves two by two on the drag-rope, while one of their number pried behind with a lever, and the canoe, bumping and sliding, was twitched through the woods. Over the sandstone flats there were some ugly ledges, but on the whole the course was down-hill and relatively easy. Looking at the way the work was done, at the good-will, the endurance, and the bull-like strength of the camaradas, and at the intelligence and the unwearied efforts of their commanders, one could but wonder at the ignorance of those who do not realize the energy and the power that are so often possessed by, and that may be so readily developed in, the men of the tropics. Another subject of perpetual wonder is the attitude of certain men who stay at home, and still more the attitude of certain men who travel under easy conditions, and who belittle the achievements of the real explorers of, the real adventures in, the great wilderness. The impostors and romancers among explorers or would-be explorers and wilderness wanderers have been unusually prominent in connection with South America (although the conspicuous ones are not South Americans, by the way); and these are fit subjects for condemnation and derision. But the work of the genuine explorer and wilderness wanderer is fraught with fatigue, hardship, and danger. Many of the men of little knowledge talk glibly of portaging as if it were simple and easy. A portage over rough and unknown ground is always a work of difficulty and of some risk to the canoe; and in the untrodden, or even in the unfrequented, wilderness risk to the canoe is a serious matter. This particular portage at Navaite Rapids was far from being unusually difficult; yet it not only cost two and a half days of severe and incessant labor, but it cost something in damage to the canoes. One in particular, the one in which I had been journeying, was split in a manner which caused us serious uneasiness as to how long, even after being patched, it would last. Where the canoes were launched, the bank was sheer, and one of the water-logged canoes filled and went to the bottom; and there was more work in raising it.

We were still wholly unable to tell where we were going or what lay ahead of us. Round the camp-fire, after supper, we held endless discussions and hazarded all kinds of guesses on both subjects. The river might bend sharply to the west and enter the Gy-Parana high up or low down, or go north to the Madeira, or bend eastward and enter the Tapajos, or fall into the Canuma and finally through one of its mouths enter the Amazon direct. Lyra inclined to the first, and Colonel Rondon to the second, of these propositions. We did not know whether we had one hundred or eight hundred kilometres to go, whether the stream would be fairly smooth or whether we would encounter waterfalls, or rapids, or even some big marsh or lake. We could not tell whether or not we would meet hostile Indians, although no one of us ever went ten yards from camp without his rifle. We had no idea how much time the trip would take. We had entered a land of unknown possibilities.

We started down-stream again early in the afternoon of March 5. Our hands and faces were swollen from the bites and stings of the insect pests at the sand-flat camp, and it was a pleasure once more to be in the middle of the river, where they did not come, in any numbers, while we were in motion. The current was swift, but the river was so deep that there were no serious obstructions. Twice we went down over slight riffles, which in the dry season were doubtless rapids; and once we struck a spot where many whirlpools marked the presence underneath of boulders which would have been above water had not the river been so swollen by the rains. The distance we covered in a day going down-stream would have taken us a week if we had been going up. The course wound hither and thither, sometimes in sigmoid curves; but the general direction was east of north. As usual, it was very beautiful; and we never could tell what might appear around any curve. In the forest that rose on either hand were tall rubber-trees. The surveying canoes, as usual, went first, while I shepherded the two pairs of lashed cargo canoes. I kept them always between me and the surveying canoes--ahead of me until I passed the surveying canoes, then behind me until, after an hour or so, I had chosen a place to camp. There was so much overflowed ground that it took us some little time this afternoon before we found a flat place high enough to be dry. Just before reaching camp Cherrie shot a jacu, a handsome bird somewhat akin to, but much smaller than, a turkey; after Cherrie had taken its skin, its body made an excellent canja. We saw parties of monkeys; and the false bellbirds uttered their ringing whistles in the dense timber around our tents. The giant ants, an inch and a quarter long, were rather too plentiful around this camp; one stung Kermit; it was almost like the sting of a small scorpion, and pained severely for a couple of hours. This half-day we made twelve kilometres.

On the following day we made nineteen kilometres, the river twisting in every direction, but in its general course running a little west of north. Once we stopped at a bee-tree, to get honey. The tree was a towering giant, of the kind called milk-tree, because a thick milky juice runs freely from any cut. Our camaradas eagerly drank the white fluid that flowed from the wounds made by their axes. I tried it. The taste was not unpleasant, but it left a sticky feeling in the mouth. The helmsman of my boat, Luiz, a powerful negro, chopped into the tree, balancing himself with springy ease on a slight scaffolding. The honey was in a hollow, and had been made by medium-sized stingless bees. At the mouth of the hollow they had built a curious entrance of their own, in the shape of a spout of wax about a foot long. At the opening the walls of the spout showed the wax formation, but elsewhere it had become in color and texture indistinguishable from the bark of the tree. The honey was delicious, sweet and yet with a tart flavor. The comb differed much from that of our honey-bees. The honey-cells were very large, and the brood-cells, which were small, were in a single instead of a double row. By this tree I came across an example of genuine concealing coloration. A huge tree-toad, the size of a bullfrog, was seated upright--not squatted flat--on a big rotten limb. It was absolutely motionless; the yellow brown of its back, and its dark sides, exactly harmonized in color with the light and dark patches on the log; the color was as concealing, here in its natural surroundings, as is the color of our common wood-frog among the dead leaves of our woods. When I stirred it up it jumped to a small twig, catching hold with the disks of its finger-tips, and balancing itself with unexpected ease for so big a creature, and then hopped to the ground and again stood motionless. Evidently it trusted for safety to escaping observation. We saw some monkeys and fresh tapir sign, and Kermit shot a jacu for the pot.

At about three o'clock I was in the lead, when the current began to run more quickly. We passed over one or two decided ripples, and then heard the roar of rapids ahead, while the stream began to race. We drove the canoe into the bank, and then went down a tapir trail, which led alongside the river, to reconnoiter. A quarter of a mile's walk showed us that there were big rapids, down which the canoes could not go; and we returned to the landing. All the canoes had gathered there, and Rondon, Lyra, and Kermit started down-stream to explore. They returned in an hour, with the information that the rapids continued for a long distance, with falls and steep pitches of broken water, and that the portage would take several days. We made camp just above the rapids. Ants swarmed, and some of them bit savagely. Our men, in clearing away the forest for our tents, left several very tall and slender accashy palms; the bole of this palm is as straight as an arrow and is crowned with delicate, gracefully curved fronds. We had come along the course of the river almost exactly a hundred kilometres; it had twisted so that we were only about fifty-five kilometres north of our starting-point. The rock was porphyritic.

The 7th, 8th, and 9th we spent in carrying the loads and dragging and floating the dugouts past the series of rapids at whose head we had stopped.

The first day we shifted camp a kilometre and a half to the foot of this series of rapids. This was a charming and picturesque camp. It was at the edge of the river, where there was a little, shallow bay with a beach of firm sand. In the water, at the middle point of the beach, stood a group of three burity palms, their great trunks rising like columns. Round the clearing in which our tents stood were several very big trees; two of them were rubber-trees. Kermit went down-stream five or six kilometres, and returned, having shot a jacu and found that at the point which he had reached there was another rapids, almost a fall, which would necessitate our again dragging the canoes over a portage. Antonio, the Parecis, shot a big monkey; of this I was glad because portaging is hard work, and the men appreciated the meat. So far Cherrie had collected sixty birds on the Duvida, all of them new to the collection, and some probably new to science. We saw the fresh sign of paca, agouti, and the small peccary, and Kermit with the dogs roused a tapir, which crossed the river right through the rapids; but no one got a shot at it.

Except at one or perhaps two points a very big dugout, lightly loaded, could probably run all these rapids. But even in such a canoe it would be silly to make the attempt on an exploring expedition, where the loss of a canoe or of its contents means disaster; and moreover such a canoe could not be taken, for it would be impossible to drag it over the portages on the occasions when the portages became inevitable. Our canoes would not have lived half a minute in the wild water.

On the second day the canoes and loads were brought down to the foot of the first rapids. Lyra cleared the path and laid the logs for rollers, while Kermit dragged the dugouts up the bank from the water with block and tackle, with strain of rope and muscle. Then they joined forces, as over the uneven ground it needed the united strength of all their men to get the heavy dugouts along. Meanwhile the colonel with one attendant measured the distance, and then went on a long hunt, but saw no game. I strolled down beside the river for a couple of miles, but also saw nothing. In the dense tropical forest of the Amazonian basin hunting is very difficult, especially for men who are trying to pass through the country as rapidly as possible. On such a trip as ours getting game is largely a matter of chance.

On the following day Lyra and Kermit brought down the canoes and loads, with hard labor, to the little beach by the three palms where our tents were pitched. Many pacovas grew round about. The men used their immense leaves, some of which were twelve feet long and two and a half feet broad, to roof the flimsy shelters under which they hung their hammocks. I went into the woods, but in the tangle of vegetation it would have been a mere hazard had I seen any big animal. Generally the woods were silent and empty. Now and then little troops of birds of many kinds passed--wood-hewers, ant-thrushes, tanagers, flycatchers; as in the spring and fall similar troops of warblers, chickadees, and nuthatches pass through our northern woods. On the rocks and on the great trees by the river grew beautiful white and lilac orchids, the sobralia, of sweet and delicate fragrance. For the moment my own books seemed a trifle heavy, and perhaps I would have found the day tedious if Kermit had not lent me the Oxford Book of French Verse. Eustache Deschamp, Joachim du Bellay, Ronsard, the delightful La Fontaine, the delightful but appalling Villon, Victor Hugo's "Guitare," Madame Desbordes-Valmore's lines on the little girl and her pillow, as dear little verses about a child as ever were written--these and many others comforted me much, as I read them in head-net and gauntlets, sitting on a log by an unknown river in the Amazonian forest.

On the 10th we again embarked and made a kilometre and a half, spending most of the time in getting past two more rapids. Near the first of these we saw a small cayman, a jacare-tinga. At each set of rapids the canoes were unloaded and the loads borne past on the shoulders of the camaradas; three of the canoes were paddled down by a couple of naked paddlers apiece; and the two sets of double canoes were let down by ropes, one of one couple being swamped but rescued and brought safely to shore on each occasion. One of the men was upset while working in the swift water, and his face was cut against the stones. Lyra and Kermit did the actual work with the camaradas. Kermit, dressed substantially like the camaradas themselves, worked in the water, and, as the overhanging branches were thronged with crowds of biting and stinging ants, he was marked and blistered over his whole body. Indeed, we all suffered more or less from these ants; while the swarms of biting flies grew constantly more numerous. The termites ate holes in my helmet and also in the cover of my cot. Every one else had a hammock. At this camp we had come down the river about 102 kilometres, according to the surveying records, and in height had descended nearly 100 metres, as shown by the aneroid--although the figure in this case is only an approximation, as an aneroid cannot be depended on for absolute accuracy of results.