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 A M A Z O N

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gardingthis river, but Wolf says that it is probably navig- long before the river attains its maximum flood-line. Thence to the Huallaga the elevation of the land is someable up to the junction of the Paute with the Zamora. what greater; but not until this river is passed, and the The Main River. Pongo de Manseriche approached, does the swelling ground The Amazon Main River is navigable for ocean of the Andean foot-hills raise the country above floodsteamers as far as Iquitos, 2300 miles from the sea, and level. 486 miles higher up for vessels drawing 14 feet The Amazon is not a continuous incline, but probably wa er as ar as character ^ j ^ Achual Point. Beyond that, consists of long, level stretches connected by short inclined istics ' according to Tucker, confirmed by Wertheman, planes of extremely little fall, sufficient, however, owing it is unsafe; but small steamers frequently to its great depth, to give the gigantic volume of water a ascend to the Pongo de Manseriche, just above Achual continuous impulse towards the ocean. The lower Amazon Point. The average current of the Amazon is about 3 presents every evidence of having once been an ocean bay, miles an hour; but, especially in flood, it dashes through the upper waters of which washed the cliffs near Obidos. some of its contracted channels at the rate of 5 miles. Only about 10 per cent, of the water discharged by the The U.S. steamer Wilmington ascended it to Iquitos in mighty stream enters it below Obidos, very little of which 1899. Commander Todd reports that the average depth is from the northern slope of the valley. The drainage of the river in the height of the rainy season is 120 feet. area of the Amazon basin above Obidos is about 1,945,000 It commences to rise in November, and increases in square miles, and, below, only about 423,000 square miles, volume until June, and then falls until the end of or say 20 per cent., exclusive of the 354,000 square miles October. The rise of the Negro branch is not syn- of the Tocantins basin. The width of the mouth of the monarch river is usually chronous ; for the steady rains do not commence in its valley until February or March. By June it is full, and measured from Cabo do Norte to Punto Patijoca, a distance then it begins to fall with the Amazon. According to of 207 statute miles; but this includes the ocean outlet, Bates, the Madeira “ rises and sinks ” two months earlier 40 miles wide, of the Par& river, which should be dethan the Amazon. The Amazon at times broadens to ducted, as this stream is only the lower reach of the 4 and 6 miles. Occasionally, for long distances, it divides Tocantins. Following the coast, a little to the north of Cabo do into two main streams with inland, lateral channels, all connected by a complicated system of natural canals, Norte, and for 100 miles along its Guiana margin up the cutting the low, flat igapo lands, which are never more Amazon, is a belt of half-submerged islands and shallow than 15 feet above low river, into almost numberless sandbanks. Here the tidal phenomenon called the bore, islands. At the narrows of Obidos, 400 miles from the or Pororoca, occurs, where the soundings are not over 4 sea, it is compressed into a single bed a mile wide and fathoms. It commences with a roar, constantly increasing, over 200 feet deep, through which the water rushes at the and advances at the rate of from 10 to 15 miles an rate of 4 to 5 miles an hour. In the rainy season it hour, with a breaking wall of water from 5 to 12 feet inundates the country throughout its course to the extent high. Under such conditions of warfare between the of several hundred thousand square miles, covering the ocean and the river, it is not surprising that the former is flood-plain, called vargem. The flood-levels are in places rapidly eating away the coast and that the vast volume of from 40 to 50 feet high above low river. Taking four, silt carried by the Amazon finds it impossible to build up a roughly equidistant places, the rise at Iquitos is 20 feet, delta. The Amazon is not so much a river as it is a gigantic at Teffe 45, near Obidos 35, and at Para 12 feet. The first high land met in ascending the river is on the reservoir, extending from the sea to the base of the Andes, north bank, opposite the mouth of the Xingu, and extends and, in the wet season, varying in width from 5 to 400 for about 150 miles up, as far as Monte Alegre. It is a miles. Special attention has already been called to the series of steep, table-topped hills, cut down to a kind of fourteen great streams which discharge into this reservoir, terrace which lies between them and the river. Monte but it receives a multitude of secondary rivers, which in Alegre reaches an altitude of several hundred feet. On any other part of the world would also be termed great. For 350 years after the discovery of the Amazon, by the south side, above the Xingii, a line of low bluffs extends, in a series of gentle curves with hardly any breaks Pinzon, in 1500, the Portuguese portion of its basin nearly to Santarem, but a considerable distance inland, remained almost an undisturbed wilderness, popuia. tion, trade, bordering the flood plain, which is many miles wide. occupied by Indian tribes whom the food quest &c Then they bend to the south-west, and, abutting upon the had split into countless fragments. It is doubt- lower Tapajos, merge into the bluffs which form the terrace ful if its indigenous inhabitants ever exceeded one to margin of that river valley. The next high land on the every 5 square miles of territory, this being the maxinorth side is Obidos, a bluff, 56 feet above the river, backed mum it could support under the existing conditions of by low hills. From Serpa, nearly opposite the river the period in question, and taking into account Indian Madeira, to near the mouth of the Rio Negro, the banks methods of life. A few settlements on the banks of the are low, until approaching Manaos, they are rolling hills; main river and some of its tributaries, either for trade but from the Negro, for 600 miles, as far up as the with the Indians or for evangelizing purposes, had village of Canaria, at the great bend of the Amazon, only been founded by the Portuguese pioneers of European very low land is found, resembling that at the mouth civilization. The total population of the Brazilian portion of the river. Vast areas of it are submerged at high of the Amazon basin in 1850 was perhaps 300,000, of water, above which only the upper part of the trees whom about two-thirds were white and slaves, the latter of the sombre forests appear. At Canaria, the high land numbering about 25,000. The principal commercial city, commences and continues as far as Tabatinga, and thence Par;i, had from 10,000 to 12,000 inhabitants, including slaves. The town of Manaos, at the mouth of the Rio up stream. On the south side, from the Tapajos to the river Negro, had from 1000 to 1500 population; but all the Madeira, the banks are usually low, although two or three remaining villages, as far up as Tabatinga, on the Brazilian hills break the general monotony. From the latter river, frontier of Peru, were wretched little groups of houses however, to the Ucayali, a distance of nearly 1500 miles, which appeared to have timidly effected a lodgment on the the forested banks are just out of water, and are inundated river bank, as if they feared to challenge the mysteries of