The New International Encyclopædia/Paraná

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PARANÁ, pä'rȧ-nä'. The largest river of South America after the Amazon, and one of the great rivers of the world. It is formed by the confluence of the Paranahyba and the Rio Grande in Southern Brazil at the common boundary point of the States of Matto Grosso, Minas Geraes, and Sao Paulo (Map: South America, D 5). The Paranahyba rises on the Serra dos Vertientes and flows southwestward on the boundary between Minas Geraes and Goyaz. The Rio Grande, which is the longer of the headstreams, and may be regarded as the true upper course of the Paraná, rises on the Serra da Mantiqueira in the Coast Range, 60 miles from the Atlantic Ocean near Rio de Janeiro. It flows northwest and westward to the confluence, whence the Paraná proper takes a southwest course through Brazil, then south on the boundary between Brazil and Paraguay, whence it curves westward between Paraguay and Argentina until it receives its largest tributary, the Paraguay River (q.v.). From this point the lower Paraná flows southwest through Argentina as far as Rosario, where it finally turns to the southeast, and enters the Atlantic Ocean through the Plata estuary at the head of which it is joined by the Uruguay River (q.v.). The total length of the Paraná River from the ocean to the source of the Rio Grande is 2950 miles, and excluding the Plata 2720 miles. The length of the lower Paraná from the Paraguay confluence is 850 miles, and with the Plata 1080 miles. The Paraná is thus longer than the Mississippi proper, and the drainage area of the system is nearly equal to that of the Mississippi.

In its upper course the Paraná flows over the great Brazilian plateau, and most of its upper tributaries, including the two headstreams, are obstructed by falls and rapids as they descend over the successive escarpments of the higher plateaus. The main river itself has the fall of Urupupunga a short distance below the confluence of the headstreams. Below this point, however, it is navigable for 600 miles over the level surface of the plateau as far as the boundary of Paraguay. Here it descends over the final great escarpment in the Falls of Guayrá, in which the river plunges through numerous rocky clefts with a total fall of 70 feet. From this point to within 150 miles of the Paraguay confluence the stream rushes through a deep gorge over a series of rocky shallows and rapids. Here the banks are heavily forested, and most of the tributaries fall into the river by cataracts, of which the Victoria Falls of the Iguassú are said to rival Niagara in height and grandeur. Below the gorge and the Paraguay confluence the river flows unobstructed through the Pampas plains, and for the last 1000 miles of its course, including the Plata, is navigiible at all seasons by large vessels, while transatlantic steamers go directly to Rosario, 400 miles from the ocean. It is 3000 yards wide at Corrientes, near the Paraguay confluence, and 7000 yards wide at Diamante. It reaches its greatest volume at Corrientes, and loses considerably by evaporation in its lower course, since it here receives scarcely any permanent tributaries except the Salado (q.v.). Several hundred miles above the estuary it begins to divide into parallel channels, inclosing a long island, and has a total width of 25 to 30 miles, while some of the channels are two miles wide. The delta proper begins 100 miles from the estuary, and consists of a vast network of channels and backwaters, emptying by 14 mouths into the Plata estuary. The main channel is accessible to the largest vessels even at low water, but all the channels are constantly and rapidly shifting, calling for great caution in their navigation. For the description of the river below the delta, see Plata, Rio de la. The Paraná was first ascended as far as the Paraguay confluence in 1526 by Sebastian Cabot.