“Such is the river, such is its history” - The Scramble for the Amazon and the Lost Paradise of Euclides da Cunha - page 194

geologistG.KarlGilbert'sdevelopmentoftheideaofisostasy,ortheideathattheearth's
surface rises as parts of it are denuded. The idea of crustal loading and release, though
empirically well elaborated, lay outside Davis's analysis or interest. 5 Davis apparently
had a domineering personality, as well as a dominant theory, so many other approaches
were relegated to the sidelines.
While Davisiscited inthefirstsentence ofdaCunha's1905essayandcompletely in-
fuses it, his name is astonishingly absent from da Cunha's later “General Observations”
exceptinanobliquereferencetothedevelopmentofestuaries.Onemightconjecturethat
da Cunha had changed his mind upon his return to Rio, after conferring with his geolo-
gist friends, musing on his data, and rethinking his ideas. He was very familiar with the
classicsofgeology,thedisciplinehemostexcelledinasastudent;itwasofspecialintel-
lectual and personal importance since his friend Orville Derby had promoted da Cunha
for the Institute of Geography and History. Da Cunha had worked with Derby in São
Paulo and stayed current in the literature. 6
In “General Observations” da Cunha is responding to several currents in the history
of ideas within geology and geomorphology: the catastrophists, who viewed transform-
ations on the earth's surface as the outcome of a cataclysmic or another singular event,
and the deists, who made Christian scripture, especially the Genesis flood, the defin-
itive framing device for understanding timing and types of events in the evolution of
landscapes. Da Cunha was also profoundly shaped by Charles Lyell, whose Principles
of Geology was the foundational text for modern geology and also influenced Darwin's
understanding of natural history. 7 According to Lyell's uniformity principle, past events
and present landscapes were formed by similar processes unfolding over extensive peri-
ods of time, and causes that transformed the earth's surface in the past remain active in
the present. His vision of landscape was rooted in continuities of incremental change
rather than divine design or simple disaster.
Da Cunha's analysis would refer mostly to the almost continental-scale research of
geologists Derby and Hartt, who embraced the ideas of plate tectonics. They explained
much of the Amazonian geology in terms of the Andean orogeny that blocked off the
great channel between the Guyana and Brazilian shield, creating an immense lake that
occupied most of the South American continent for a significant part of its geological
history. They also noted the continent's geological affinities with Africa. Da Cunha also
invoked the work of Frederich Katzer, the German paleontologist (and Pará museum re-
searcher) who commented on the relation and similarities of Amazonian geologies with
those of Africa, causing a sensation in European circles. 8 Da Cunha's view was syncret-
ic: while embracing Lyell's basic position about the continuity of processes in shaping
landscapes, he followed the arguments developed byHartt and Derby that saw the Purús
and the Juruá generated from the rise of the Andes, their structure and geology having