THE AMAZON VALLEY. 2S9
is laid down with tolerable accuracy. I have narrated in my Journal how I was prevented from descending on the north side of it, and thus completing my survey of its course.
The most remarkable feature is the enormous width to which it spreads, — first, between Barra and the mouth of the Rio Branco, and from thence to near St. Isabel. In some places, I am convinced, it is between twenty and thirty miles wide, and, for a very great distance, fifteen to twenty. The sources of the rivers Uaupes, Isanna, Xie, Rio Negro, and Guaviare, are very incorrectly laid down. The Serra Tunuhy is generally represented as a chain of hills cutting off these rivers ; it is, however, a group of isolated granite peaks, about two thousand feet high, situated on the north bank of the river Isanna, in about i° north latitude and 70 west longitude. The river rises considerably beyond them, in a flat forest- country, and further west than the Rio Negro, for there is a path across to the Iniriza, a branch of the Guaviare which does not traverse any stream, so that the Rio Negro does not there exist.
My own journey up the Uaupe's extended to near 72 west longitude. Five days further in a small canoe, or about a hundred miles, is the Jurupari caxoeira, the last fall on the river. Above that, traders have been twelve days' journey on a still, almost currentless river, which, by the colour of its water, and the aspect of its vegetation, resembles the Upper Amazon. For all this distance, which must reach very nearly to the base of the Andes, the river flows through virgin forest. But the Indians in the upper part say there are campos, or plains, and cattle, further up; and they possess Spanish knives and other articles, showing that they have communications with the civilised inhabitants of the .country to the east of Bogota.
I am therefore strongly inclined to believe that the rivers Ariari and others, rising about a hundred miles south of Bogota, are not, as shown in all our maps, the sources of the Guaviare, but of the Uaupes, and that the basin of the Amazon must therefore be here extended to within sixty miles of the city of Bogota This opinion is strengthened by information obtained from the Indians of Javita, who annually ascend the Guaviare to fish in the dry season, and who state that the river is very small, and in its upper part, where some hills occur and the
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