EIO GEANDE DO SUL— KIVERS. 239 



Rivers. 



Numerous rivers converge iu tlie Lagoa dos Patos, which sends its overflow 

 through the Hio Grande to the Atlantic. The chief affluent, known by various 

 names, is formed towards the centre of the State by the junction of the Yacacahy 

 and Jacuhy, the latter being considered the main branch. Below a great cataract 

 the river becomes navigable, and rapidly increases in volume by the contributions 

 of the Taquary, Cahy, Rio dos Sinos, and other tributaries, mostly descending 

 from the northern uplands. I^ovver down the Jacuhy develops into an estuary, 

 and under the name of Guahyba, fulls through a strait into the Lagoa dos 

 Patos. 



The Lagoa Mirim is fed by the Cebolaty from Uruguay and by the Jaguarào 

 frontier stream, and discharges its overflow north-eastwards to the Lagoa dos 

 Patos through the Sangradouro (S. Goncalo) channel. This emissary, which is 

 joined by the Rio Piratinim, has been deepened and canalised, and is now 

 utilised by tradiug steamers between the two lagoons. Unfortunately a dan- 

 gerous bar, the scene of man}^ shipwrecks, obstructs the navigation of the Rio 

 Grande do Sul, through which this extensive system of inland waters com- 

 municates with the Atlantic. 



On the north-east and north-west Rio Grande is bounded by the Uruguay, 

 which rises within Brazilian territory, and for the greater part of its course 

 either flows through or borders Brazilian lands. It has its source in the Serra 

 do Mar, within thirty miles of the Atlantic, and under various names traverses 

 the region of the campos. From Rio Grande it receives the Uruguay Mirim, 

 " Little Uruguay," and from Santa Catharina numerous affluents, amongst others, 

 the Chapeco and Pepiry Guassu, which have given rise to so many discussions on 

 the subject of the Brazilo- Argentine frontiers. 



Below the PejDiry Guassu, " Big Straw-Coloured River," the Uruguay forms 

 the Salto Grande, " Great Falls," where it turns abruptly from the west to the 

 south-west, retaining this direction throughout the whole section of its course 

 between the conterminous republics. In this region its largest affluent is the 

 Ibicuy Grande, which is accessible to small craft for some hundred miles. The 

 mainstream is also navigable, but interrupted at intervals by rapids, so that free 

 navigation begins far to the south of Brazilian territory below the rapids at Salto, 

 a town in Uruguay. 



Climate. 



In Rio Grande, southernmost of the Brazilian States, the seasons are as 

 distinctly marked as in Europe, and the range of temperature between the hot 

 summers and cold winters sometimes exceeds 70° Fahr. In January and February 

 the thermometer has recorded 100° and 102° Fahr., while the ground is covered with 

 snow in July. In the hilly districts the glass falls at times to 17° or 16° Fahr., but 

 such extremes are rare, and the mean range between the greatest heat and 



