STATES OF THE S. FRANCISCO BASIN. 153 



Santo, mainly a forest zone of difficult access, has made rapid progress in recent 

 years. Collectively the four States comprise a supsrficial area of about 434,000 

 square miles, with a population (1893) of 5,570,000. 



Progress of Discovery and Settlement. 



The vast bay of Todos os Santos, on which now stands the city of Bahia, was 

 already sighted by Christovào Jaques in 1503, three years after the discovery of 

 the Brazilian coast. The colony developed rapidly in the second half of the 

 sixteenth century, after Bahia had been chosen as capital of all the Brazilian 

 captainries. But the forest-clad seaward slopes long presented an insurmount- 

 able barrier to the occupation of the interior. Expeditions were, however, under- 

 taken towards the unknown lands traversed by the Upper S. Francisco, whence 

 Marcos de Azevedo brought silver and emeralds in 1650. Twenty years later 

 some daring Paulistas, under Fernando Dias Paes Leme, pushed northwards to the 

 regions reported to abound in precious stones. They reached the sources of the 

 Pio Doce without, however, discovering the treasures for which this district after- 

 wards became famous. 



Other Paulistas were more fortunate, and in 1720 the Portuguese Government, 

 in order to secure its mineral revenues, constituted the captainry of Minas Geraes 

 with about the same limits as those of the present State. Each of the new mining 

 centres became starting-points for fresh explorations, and since the era of scien- 

 tific research was opened by Humboldt, the whole land has been traversed by 

 Yon Eschwege, Auguste de Saint-Hilaire, Spix and Martins, Mawe, Gardener, 

 Spruce, Burton, Liais, Halfeld, Wells, Manoel de Macedo, and others. In 1815-17 

 Max von Wied visited and carefully described the Botocudos ; Lund devoted 

 many years to the study of the extinct fauna of the Caves ; Gorceix, Hartt, Fer- 

 rand, Orville, Derby, and many other miners, engineers, and geologists examined 

 the character of the rocks and their mineral treasures, and a beginning has 

 been made with a topographic map to the scale of T7rô"!ô""ô"ô", which is to be con- 

 nected with woi'ks of a like nature now progressing in the State of S. Paulo. 



Physical Features. 



To the mountainous region where the Rio S. Francisco takes its rise, the term 

 campos, " plains," or " fields," is sometimes applied ; but these upland plains pre- 

 sent no such level spaces as the Venezuelan llanos. The sui'face is everywhere 

 broken by hills rising from 300 to 600 feet above the normal height of the vast 

 plateau. One of the loftiest summits in Minas even takes the name of Itabira do 

 Campo, in contradistinction to the less elevated Itabira da Serra, or do Matto 

 Dentro, in the mountainous and wooded eastern regions. 



The mean altitude of these uplands, which form the central water-parting 

 of Brazil, and which slope in all directions, is about 3,000 feet, while the 

 culminating peaks between Queluz and Barbacena exceed 4,000 feet. From 

 this central nucleus diverge the various ranges, which rise above the common 

 pedestal, and which nearly everywhere decrease with it in altitude. 



