Returning to more genial climes, and passing the am ple estuary of the Rio de la Plata, we discover, skirting the Atlantic Ocean, a narrow extended but very inte resting slope. The Brazilian table land, inclining a very little from the meridian towards N. E. and S. W. extends in broken fragments from the outlet of the Plate basin to that of the Amazon, giving existence and course to numerous rivers. If not on the same conti nent, and contrasted with the Orinoco, Amazon, and Plate, a respectable rank would be due to such rivers as Rio Grande, St. Francis, and Parnaiba.
Much confusion has arisen in Spanish American geo graphy, by a multiplication of the same names. Several rivers are known by the title of Rio Grande, one of which, a very remarkable stream, is disembogued into the Atlantic Ocean, almost on S. lat. 32°. What is call ed here Rio Grande, is however only the mere discharge of a basin of about 500 miles from S. W. to N. E. and with a mean width of 140, area 70,000 square miles.
Two large lakes, the Laguna Patos, 150 by 50 miles, and the Laguna Merin, something less in length and breadth, lie parallel to the opposing coast, the latter dis charging its water into the former, and both fed by nu merous rivers flowing from the interior table land.
Between S. lat. 20° and 28°, and north-eastward from the basin of Rio Grande, extends a narrow zone, varying from about 150, to less than 50 miles wide, and 900 in length ; having the Atlantic Ocean S. E. and the sources of the Parana N. W. Besides many smaller streams traversing this well watered tract, are the Ribeira and St. James, of considerable length of course. With S. lat. 20°, the Brazil slope of South America widens ra pidly, the table land inclining west of north, and stretching towards the mouth of the Tocantinas. The rivers entering the Atlantic between S. lat. 11 and 20°, are excessively numerous, though of abridged course. The limited length of those rivers, as produced by one of those singular phenomena, which render the geogra phy of South America peculiar. The St. Francis de rives its highest sources interlocking with those of the Parana, within 200 miles from the Atlantic coast, and as far south as lat. 21°. Pursuing a northern course of 400 miles, the St. Francis inflects gradually to the north-east, east, and south-east, enters the Atlantic Ocean at S. lat.
11°, after an entire comparative course of upwards of 1100 miles, and in this long course overhcading the in termediate Atlantic rivers.
On the same slope, and nearly due west from tho mouth of the St. Francis, and interlocking sources with that river, and with the Tocantinas, rises the Parnaiba. The latter inclining to N. N. E. and after a comparative course of six hundred miles is lost in the Atlantic Ocean, at S. lat. 40'.
Sweeping round the extreme eastern protrusion of South America, forming politically the Brazilian pro vinces of Pernambuco and Ceara, in a distance of 900 miles from the mouth of St. Francis to that of Parnaiba, the rivers are found still more confined in their courses than on any other part of the oceanic margin of South America ; but front the estuary of the Parnaiba to that of the Amazon, or rather to that of the Tocantinas, the Pinare, Gurupy, Capim, and some others, flow from two to three hundred miles, before their exit into the Atlantic.
Passing the estuary of the Amazon, we discover be tween that outlet and the Delta of the Orinoco, another detached slope extending from south-cast to north-west about one thousand miles, with a mean width of 150 miles; superficies 150,000 square miles. This region, to which, by a rare felicity, a general and elegant name has been given, Guyana, is nearly commensurate with the natural section we arc describing, and from extended European colonization is a very interesting portion of maritime South America. Similar to the other parts of the oceanic border of that continent, the sea coast of Guyana is much indented by rivers, though only three, the Essequibo, Surinam, and Marowinc, are of magni tude worthy notice.
The most considerable of these rivers, the Essequibo, is formed by two branches, the Cuyuni from the north west, of 300 miles comparative course, and the Essequi bo proper from the south, of 400 miles comparative course. Uniting at the town of Essequibo, the confluent waters open in a wide bay, which terminate in the Atlantic Ocean at N. lat. The Surinam or Surimaca, rises in the same moun tainous ridge as the Essequibo, but the former flowing eastward about 100 miles on N. lat. turns abruptly to the north, and continuing that direction, is finally lost in the Atlantic Ocean at N. lat. 6°.