CHAPTER I 
Topography and Physical Geography of South Brazil 
EVIDENCE Ol SUBSIDENCE 
The region comprised by the writer’s studies and travels covers 
in part the three most southern states of Brazil; viz, Rio Grande do 
Sul, Santa Catharina, and Parand. Some excursions were also made 
into S. Paulo, and through eastern Minas Geraes, as well as to Marahtt 
on the coast of Bahia, but no serious study was possible in the three 
last mentioned states for want of sufficient time. 
The whole coast line, at ieast from Rio de Janeiro southward, 
appears to present evidence of submergence, so that the rivers, bays, 
and islands exhibit the aspect, of drowning similar to that shown 
by the rivers and bays of Nova Scotia, Cape Breton, and Newfoundland. 
This drowning is indicated alike hy the depth to solid bed-rock 
at the mouths of rivers as well as the absence of any old beach de- 
posits at elevations sensibly above the present shore lines, True, we 
often find sand deposits and old dunes piled up to 20, or even 30, 
meters above sea level, and extending far inland, but this is nothing 
more than we see taking place along the present beaches, so that 
the presence of these low sandy plains, especially from Florianopolis 
southward to the extreme point of Rio Grande do Sul, is no evidence 
of modern crustal elevation. 
The amount of coastal depression appears to increase southwards 
judging by the only data at hand; viz, the borings for the harbor 
works at Rio de Janeiro, where solid rock occurs near shore at about 
45-20 meters below tide, while at Pelotas, the depth to the underlying 
granite is over one hundred ( 102) meters. 
The record ofa boring made there in 1856-1862 has fortunately 
been preserved, and a copy of the same kindly given me by his honor, 
Dr. F. de P. Gonealves Moreira, the mayor of Pelotas. The 
