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 A M A Z O N

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mouth of the Ucayali, Reclus the same, both following the missionary fathers of the colonial period. M. de la Condamine uses “Amazon” and “Maranon” indiscriminately, and considers them one and the same. Smith and Lowe give the mouth of the Javary as the eastern limit, as does d’Orbigny. Wolf, apparently uncertain, carries the “Marahon or Amazon” to the Peruvian frontier of Brazil, at Tabatinga. Other travellers and explorers contribute to the confusion. This probably arises from the rivalry of the Spaniards and Portuguese. The former accepted the name Marahon, in Peru, and as the missionaries penetrated the valley they extended the name until they reached the Ucayali; while, as the Portuguese ascended the Amazon, they carried its name to the extent of their explorations. Beginning with the lower

river we propose to notice, first, the great affluents which go to swell the volume of the main stream.

In finding its way to the lowlands, it breaks frequently into falls and rapids, or winds violently through rocky gorges, until, at a point about 100 miles above its junction with the Tocantins, it saws its way across a rocky dyke, for 12 miles, in roaring cataracts. The tributaries of the Tocantins, called the Maranhao and Parana-tinga, collect an immense volume of water from the highlands which surround them, especially on the south and southeast. Between the latter and the confluence with the Araguay, the Tocantins is occasionally obstructed by rocky barriers which cross it almost at a right angle. Through these, the river carves its channel, broken into cataracts and rapids, or cachoeiras, as they are called throughout Brazil. Its lowest one, the Itaboca cataract, is about 130 miles above its estuarine port of Cameta, for which distance the river is navigable; but above that it is useless as a commercial avenue, except for laborious and very costly transportation. The flat, broad valleys, composed of sand and clay, of both the Tocantins and its Araguay branch, are overlooked by steep bluffs. They are the margins of the great sandstone plateaux, from 1000 to 2000 feet elevation above sea-level, through which the

rivers have eroded their deep beds. Around the estuary of the Tocantins the great plateau has disappeared, to give place to a part of the forest-covered, half-submerged alluvial plain which extends far to the north-east and west. The Par& river, generally called one of the mouths of the Amazon, is only the lower reach of the Tocantins. If any portion of the waters of the Amazon runs round the southern side of the large island of Marajo into the river Par&, it is only through tortuous, natural canals, which are in no sense outflow channels of the Amazon. The Xingu, the next large river west of the Tocantins, is a true tributary of the Amazon. It was but little known until it was explored in 1884-87 by von den Steinen, from Cuyaba. Travelling east, 240 miles, he found the river Tamitatoaba, 180 feet wide, flowing from a lake 25 miles in diameter. He descended this torrential stream to the river Romero, 1300 feet wide, entering from the west, which receives the river Colisu. These three streams form the Xingu, or Parana-xingu, which, from 73 miles lower down, bounds along a succession of rapids for 400 miles. A little above the head of navigation, 105 miles from its mouth, the river makes a bend to S. I. — 44

Tributaries. The Tocantins is not really a branch of the Amazon, although usually so considered. It is the great central fluvial artery of Brazil, running from south to north for a distance of about 1500 miles. It rises in the mountainous district known as the Pyrenees; but its more ambitious western affluent, the Araguay, has its extreme southern headwaters on the slopes of the Serra Cayapd, and flows a distance of 1080 miles before its junction with the parent stream, which it appears almost to equal in volume. Besides its main tributary, the Rio das Mortes, it has twenty smaller branches, offering many miles of canoe navigation.