102 AMAZONIA AND LA PLATA. 



Salinas Point, east of the Rio Para, and Santa Anna, east of MaranLâo, have both 

 lost ground, while Caviana in the archipelago crossed by the equator has been 

 cut in two by a strait formed by the gradual expansion of two creeks on oppo- 

 site sides of the island. 



But what becomes of the prodigious quantities of sediment continually 

 washed down by the Amazons, which, unlike the Mississippi and so many other 

 great rivers, builds up no delta at its mouth ? This sediment probably represents 

 a cube 500 feet on all sides floated down every 24 hours. Such a mass 

 spread over the estuary and surrounding waters would rapidly raise the marine 

 bed but for the great equatorial current, by which it is caught up and distributed 

 along the coast in the direction of the north-west. Some of the matter held in 

 solution is thus deposited on the Guiana seaboard, while much more is dispersed 

 over the West India waters, and especiall}^ along the shores of Georgia and both 

 Carolinas. Here should probably be sought the true Amazonian delta ; here 

 would seem to be deposited the alluvial matter incessantly washed down from 

 the equatorial Andes. 



Navigation or the Amazons. 

 Before the introduction of steam, sailing craft took five full months to ascend 

 from Para to the " bar " of the Rio Negro, and five more to stem the current as 

 far as the Peruvian frontier. At that time the circumnavigation of the globe 

 even against unfavourable winds and currents took less time than the ascent of 

 the Amazons with the trade winds setting steadily up stream. Steam, aided, 

 since 1867, by the opening of the river to all flags, has effected a revolution in the 

 Amazonian world, the consequences of which are making themselves felt more 

 and more every year. The region of the Upper Amazons, formerly cut off from 

 the great trading centres, has, so to say, been brought to the shores of the Atlantic, 

 which is continued into the interior of the continent by the great river, presenting 

 with its endless ramifications a prodigious system of navigable waters over 

 30,000 miles in extent. If the whole of Brazil be viewed as an island encircled 

 by oceanic and fluvial waters, its periphery may be taken at about 14,000 miles, of 

 which 3,500, or about one-fourth, belong to the Amazonian system. 



Subjoined is a table of the mainstream with its more imjDortant Brazilian 

 aflluents : — 



