1911 Encyclopædia Britannica/São Francisco

SÃO FRANCISCO, a river of eastern Brazil rising in the S.W. part of the state of Minas Geraes, about 20° 30′ S., 46° 40′ W., near the narrow valley of the Rio Grande, a tributary of the Parana, and within 240 m. of the coast W. of Rio de Janeiro. It flows in a general N.N.E. direction across the great central plateau of Brazil to about lat. 9° 30′ S., long. 42° W., where it turns N.E. and then S.E. in a great bend, entering the Atlantic in lat. 10° 29′ S. It has a total length of about 1800 m. and a fall of 2700–2800 ft. It is navigable from the Atlantic to Piranhas (148 m.) and is nearly 1 m. wide at Penedo, 22 m. from the sea. Above Piranhas, about 193 m. from its mouth, are the falls of Paulo Añonso where the river plunges through a narrow gorge—in one place only 51 ft. wide—and over three successive falls, all together 265 ft. The obstructed part of the river is about 190 m. long and consists of a series of rapids above the falls and a deep canon with whirlpools for some distance below. The Brazilian government has built a railway around these falls from Piranhas (151 ft. elevation) to Jatobá (978 ft.) with an extension of 71 m. Above Jatobá there is another series of rapids called the Sobradinho nearly 90 m. above the lower rapids, which are navigable at high water, and above these an unobstructed channel for light-draught river boats up to Pirapora a little above the mouth of the Rio das Velhas, a distance of 984 m. Here the river runs through a barren, semi-arid region, sparsely settled. There are no tributaries of consequence along a large part of this region, and the few people living beside the river are dependent on its annual floods for the fertilization of its sandy shores on which their scanty plantations of Indian corn and beans are made. The rapids of Pirapora are 17 m. above the mouth of the Rio das Velhas, and this point, the head of navigation on the river, and 1742 ft. above sea-level, is the objective point of the Central do Brazil railway, the purpose being to create by rail and river a central route from Rio de laneiro to the northern ports of Bahia and Recife. The principal tributaries of the Sao Francisco are: on the right, the Para, Paraopeba, Velhas, and Verde-Grande; on the left, the Indaya, Abaeté, Paracatú, Urucuya, Carinhanha, Corrente and Grande. Several of these tributaries are navigable for long distances by small boats—the aggregate being a little over 1000 m. Some authorities give the aggregate navigable channels of the São Francisco as 4350 m. The upper valley of the São Francisco is partly forested, has a temperate climate, with a mean annual temperature of 85° and a rainfall of 1637 millimetres. The rainy season is from December to March, but on the lower river the rainfall is light and the season much shorter, sometimes varied by, droughts covering several years.

An admirable description of this great river is given by Richard Burton in The Highlands of Brazil (2 vols., London), and a more technical description by E. Liais in Hydrographie du Haut San-Francisco et du Rio das Velhas (Rio de Janeiro, 1865).