AMAZONIA. 91 



the Rio de las Amazonas. For the riverine Indians it was the Parana Tino-a. 

 " White River," the Parana Guassu, " Great River," or simply Para, " River" in 

 a pre-eminent sense, a name now restricted to a lateral channel connected with the 

 Amazons system. Lastly the Brazilians have conferred on their majestic stream 

 the title of Rio Mar, " Sea River." 



Before the days of steam the Amazons was seldom visited, and to the missionarv 

 Fritz (1690) is due the first chart of its course, rectified in 1749 by La Condamine. 

 Then came in the present century the scientific explorations of Spix and Martius, 

 of Castelnau, Herndon, Gibbon, Orton, Myers, Spruce, Wallace, Bates, de la Espada, 

 Agassiz, Hartt, Barbosa Rodrigues, José da Costa Azevedo, and Tardy de Mon- 

 travel. 



On the Brazilian frontier, the Amazons flows at a level of not more than 270 

 feet above the sea ; here it is nearly two miles wide and already presents the impos- 

 ing aspect which it retains for the rest of its seaward journey. Several of the 

 affluents themselves enter the main stream through mouths of enormous width. 

 The waters of some are of the same yellowish colour as the Amazons itself, while 

 others are of divers tints, clear and turbid, white or reddish, or even black, though 

 limpid, each revealing a page of its geological history in its peculiar shade and 

 in the sediment it holds in solution. 



The Putumayo and Japuka. 



The northern affluents descend from a zone only half as broad as that traversed 

 by those from the south ; hence their contributions, however copious, are in gene- 

 ral much smaller than those of the southern streams. Nevertheless one of them, 

 the Tea, that is, the Putumayo of the Colombians, would seem to be relatively 

 the most voluminous ; its headwaters, rising north and south of the equator, 

 descend from the eastern slopes of the Quito highlands, which are exposed to 

 heavy rains throughout the year. The Putumayo is one of those rivers which 

 have most contributed to the erosion of the Andine system, reducins: it in Ecuador 

 to a comparatively narrow ridge between the broader Colombian and Peruvian 

 masses. The Guames (Guamues), one of its head branches, issues from the Cocha, 

 or " Lake," as it is called pre-eminently, and below its junction the Putumayo 

 soon becomes accessible to barges drawing six or seven feet. It flows along a 

 gentle incline imobstructed by reefs or rapids, at a sharp angle with the Amazons, 

 and in Brazilian territory is known only by its Indian (Omagua) name, Iça. It 

 was first visited by the Jesuit, Juan de Sosa, in 1609, and in recent times has been 

 surveyed by Rafael Reyes (1874), Simson (1876), and Crevaux (1879). Like 

 the Napo, the Japura, and other Ecuador tributaries, the Iça floats down much 

 pumice from the slopes of the volcanoes, and this pumice accumulates in masses 

 along all the chalk clifis of the Amazons. 



The Japura (Hyapura) rises a little north of the Putumayo in the Colombian 

 Andes, and both streams flow in nearly parallel courses to a point where the 

 Lower Japura trends directly east, joining the Amazons through a labyrinth of 

 channels. Its incline is much greater than that of the Iça, and after issuing from 



