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 AMAZON and, for the remaining seven months, only canoes can ascend it sufficiently high to communicate overland with the settlements in the great india-rubber districts of the Mayu-tata and lower Beni : thus these regions are forced to seek a canoe outlet for their rich products by the very dangerous, costly, and laborious route of the falls of the Madeira. The Jurua is the next great southern affluent of the Amazon west of the Punis, sharing with this the bottom of the immense inland Amazon depression, and having all 1 the characteristics of the Punis as regards curvature, sluggishness, and general features of the low, half-flooded forest country it traverses. It rises among the Ucayali highlands, and is navigable and unobstructed for a distance | of 1133 miles above its junction with the Amazon. The Javary, the boundary line between Brazil and i Peru, is another Amazon tributary of importance. It is supposed to be navigable, by canoe, for 900 miles above its mouth to its sources among the Ucayali highlands, but only 260 have been found suitable for steam navigation. The Brazilian Boundary Commission ascended it, in 1866, to the junction of the Shino with its Jaquirana branch. The country it traverses in its extremely sinuous course is very level, similar in character to that of the .1 urua, and is a forested wilderness occupied by a few savage hordes. The Ucayali, which rises only about 70 miles north of Lake Titicaca, is the most interesting branch of the Amazon next to the Madeira. Peru has fitted out many costly and ably-conducted expeditions to explore it. One of them (1867) claimed to have reached within 240 miles of Lima, and the little steamer Napo forced its way up the violent currents for 77 miles above the junction with the Pachitea river as far as the river Tambo, or Apurimac, 770 miles from the confluence of the Ucayali with the Amazon. The Napo then succeeded in ascending the Urubamba branch of the Ucayali 35 miles above its union with the Tambo, to a point 200 miles north of Cuzco. The remainder of the Urubamba, as shown by Bosquet in 1806, and Castelnau in 1846, is interrupted by cascades, reefs, and numberless other obstacles to navigation. The Tambo, which rises in the Yilcanota knot of mountains south of Cuzco, is a torrential stream valueless for commercial purposes. The banks of the Ucayali for 500 miles up are low, and, in the rainy season, extensively inundated. The Huallaga, which joins the Amazon to the west of the Ucayali, rises high among the mountains, in about 10° 30' S. lat., on the slopes of the celebrated Cerro de Pasco. For nearly its entire length, it is an impetuous torrent running through a succession of gorges. It has forty-two rapids, its last obstruction being the Pongo de Aguirre, so called from the traitor Aguirre, who jwissed there. To this point, 140 miles from the Amazon, the Huallaga can be ascended by large river steamers. Between the Huallaga and the Ucayali lies the famous “ Pampa del Sacramento,” a level region of stoneless alluvial lands covered with thick, dark forests, first entered by the missionaries in 1726. It is about 300 miles long, from north to south, and varies in width from 40 to 100 miles. Many streams, navigable for canoes, penetrate this region from the Ucayali and the Huallaga. It is still occupied by savage tribes. The river Mar anon rises about 100 miles to the northeast of Lima. It flows through a deeply-eroded Andean valley, in a north-west direction, along the eastern base of the Cordillera of the Andes, as far as 5 36 S. lat.; then it makes a great bend to the north-east, and with irresistible power cuts through the inland Andes, until, at the Pongo de Manseriche, it victoriously breaks away from the

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mountains to flow onwards through the plains under the name of the Amazon. Barred by reefs, and full of rapids and impetuous currents, it cannot become a commercial avenue. At the point where it makes its great bend, the river Chinchipe pours into it from southern Ecuador. Just below this, the mountains close in on either side of the Marahon, forming narrows or pongos, for a length of 35 miles, where, besides numerous whirlpools, there are no less than thirty-five formidable rapids, the series concluding with three cataracts just before reaching the river Imasa, or Chunchunga, near the mouth of which La Condamine embarked, in the 18th century, to descend the Amazon. Here, the general level of the country begins to decrease in elevation, with only a few mountain spurs, which, from time to time, push as far as the river and form pongos of minor importance, and less dangerous to descend. Finally, after passing the narrows of Guaracayo, the cerros gradually disappear, and, for a distance of about 20 miles, the river is full of islands, and there is nothing visible from its low banks but an immense forest-covered plain. But the last barrier has yet to be passed, the Pongo de Manseriche, 3 miles long, just below the mouth of the Bio Santiago, and between it and the old abandoned missionary station of Borja, in 38° 30' S. lat. and 77° 30' 40" W. long. According to Captain Carbajal, who descended it in the little steamer Napo in 1868, it is a vast rent in the Andes about 2000 feet deep, narrowing in places to a width of only 100 feet, the precipices “seeming to close in at the top.” Through this dark canon, the Maranon leaps along, at times, at the rate of 12 miles an hour.1 From the northern slope of its basin, the Amazon receives many tributaries, but their combined volume of water is not nearly so great as that contributed to the parent stream by its affluents from the south. That part of Brazil lying between the Amazon and French, Dutch, and British Guiana, and bounded on the west by the Rio Negro, is known as Brazilian Guiana. It is the southern watershed of a tortuous, low chain of mountains running, roughly, east and west. Their northern slope, which is occupied by the three Guianas first named, is saturated and river-torn ; but their southern one, Brazilian Guiana, is in general thirsty and semi-barren, and the driest region of the Amazon valley. It is an area which has been left almost in the undisturbed possession of nomadic Indian tribes, whose scanty numbers find it difficult to solve the food problem. From the divortium aguarum between French Guiana and Brazil, known as the Tumuc-humac range of highlands, two minor streams, the Yary and the Paron, reach the Amazon across the intervening broken and barren tableland. They are full of rapids and reefs. The Trombetas is the first river of importance we meet on the northern side as we ascend the Amazon. Its confluence with this is just above the town of Obidos. It has its sources in the Guiana highlands, but its long course is frequently interrupted by violent currents, rocky barriers, and rapids. The inferior zone of the river, as far up as the first fall, the Porteira, has but little broken water and is low and swampy; but above the long series of cataracts and rapids the character and aspect of the valley completely change, and the climate is much better. The river is navigable for 135 miles above its mouth. The Negro, the great northern tributary of the Amazon, has its sources along the watershed between the Orinoco and the Amazon basins, and also connects with the Orinoco at one point. Its main affluent is the Uaupes, which disputes with the headwaters of the Guaviari 1 One of the most daring deeds of exploration ever known in South America was done by the engineer A. Wertheman. He fitted out three rafts, in August 1870, and descended this whole series of rapids and cascades from the Rio Chinchipe to Borja.