he Parana there is an open channel of 276 m.,
passing through a rich and healthy country, and receiving large
tributaries from one of the most fertile regions of Brazil. Among the
larger of these are the great falls of the Iguassu, near the junction
of that river with the Parana. Though the Uruguay plays a less
important part, its relations to the country are similar to those of
the Parana, and its tributaries from the plateau region are similarly
broken by falls and rapids. The Paraguay is in great part a lowland
river, with a sluggish current, and is navigable by large river
steamers up to Corumba, and by smaller steamers to Cuyaba and the
mouth of the Jauru.

Lakes.

Compared with the number, length and volume of its rivers, Brazil has
very few lakes, only two of which are noticeable for their size. There
are a number of lakes in the lowland region of the Amazon valley, but
these are mainly overflow reservoirs whose areas expand and contract
with the rise and fall of the great river. The coastal plain is also
intersected by lagoons, lakes and inland channels formed by uplifted
beaches. These inland channels often afford many miles of sheltered
navigation. The lakes formed in this manner are generally shallow, and
are sometimes associated with extensive swamps, as in southern Bahia.
The lakes of the Alagoas coast, however, are long, narrow and deep,
occupying valleys which were deeply excavated when the land stood at a
higher level, and which were transformed into lakes by the elevation
of the coast. The largest of these are the Lagoa do Norte, on whose
margin stands the city of Maceio, and the Lagoa do Sul, a few miles
south of that city. Both have outlets to the sea, and the former is
salt There is a large number of these lakes along the coasts of
Espirito Santo and Rio de Janeiro, some of them of considerable size.
The two largest lakes of this class are on the coast of Rio Grande do
Sul and are known as the Lagoa dos Patos and Lagoa Mirim. Both of
these lakes lie nearly parallel with the coast line, are separated
from the ocean by broad sand beaches filled with small lakes, and
communicate with the ocean through the same channel. The Lagoa dos
Patos is about 124 m. long with a maximum width of 37 m., and Lagoa
Mirim is 108 m. long with a maximum width of 15 m. Both are navigable,
though comparatively shallow and filled with sandbanks. So