[Igarapé, or Canoe-path.]

But extraordinary as is this network of natural canals, the tributaries of the Amazon are still more wonderful. They are so numerous they appear on the map like a thousand ribbons streaming from a main mast, and many of the obscure affluents, though large as the Hudson, are unknown to geography. From three degrees north to twenty degrees south, every river that flows down the eastern slope of the Andes is a contributor—as though all the rivers between Mexico and Mount Hooker united their waters in the Mississippi. While the great river of the northern continent drains an area of one million two hundred thousand square miles, the Amazon (not including the Tocantíns) is spread over a million more, or over a surface equal to two thirds of all Europe. Let us journey around the grand trunk and take a glimpse of the main branches.

The first we meet in going up the left bank is the Rio Negro. It rises in the Sierra Tunuhy, an isolated mountain group in the llanos of Colombia, and enters the Amazon at Manáos, a thousand miles from the sea. The upper part, down to the parallel of one degree north, has a very rapid current; at San Gabriel are the first rapids in ascending; between San Gabriel and Barcellos the rate is not over two or three miles per hour; between Barcellos and Manáos it is a deep but sluggish river, and in the annual rise of the Amazon its waters are stagnant for several hundred miles up, or actually flow back. Its extreme length is twelve hundred miles, and its greatest breadth is at Barcellos, where it is twelve or fifteen miles. Excepting this middle section, the usual breadth of the Negro below the equatorial line is about one mile. It is joined to the Orinoco by the navigable Cassiquiari,[151] a natural canal three fourths of a mile wide, and a portage of only two hours divides the head of its tributary, the Branco, from the Essequibo of Guiana. The Negro yields to commerce coffee, cacao, farina, sarsaparilla, Brazil nuts, pitch, piassaba, and valuable woods. The commerce of Brazil with Venezuela by the Rio Negro amounted in 1867 to $22,000, of which $9000 was the value of imports. The principal villages above Manáos are San Miguel and Moroa (which contain about fifty dwellings each), Tireguin, Barcellos, Toma, San Carlos, Coana, San Gabriel, and Santa Isabel.

The next great affluent is the Japurá. It rises in the mountains of New Granada, and, flowing southeasterly a thousand miles, enters the Amazon opposite Ega, five hundred miles above Manáos. Its principal mouth is three hundred feet wide, but it has a host of distributing channels, the extremes of which are two hundred miles apart. Its current is only three quarters of a mile an hour, and it has been ascended by canoes five hundred miles. A natural canal like the Cassiquiari is said to connect it with the Orinoco. The products of the Japurá are sarsaparilla, copaiba, rubber, cacao, farina, Brazil nuts, moira-piránga—a hard, fine-grained wood of a rich, cherry-red color—and carajurú, a brilliant scarlet dye.

Parallel to the Japurá is the Putumayo or Issá. Its source is the Lake of San Pablo, at the foot of the volcano of Pasto; its mouth, as given by Herndon, is half a mile broad, and its current two and three fourths miles an hour.

Farther west are the Napo and Pastassa, starting from the volcanoes of Quito. The former is nearly seven hundred miles long, navigable five hundred. The latter is an unnavigable torrent. One of its branches, the Topo, is one continued rapid; "of those who have fallen into it, only one has come out alive." Another, the Patate, rises near Iliniza, runs through the plain to a little south of Cotopaxi, receives all streams flowing from the eastern side of the western Cordillera from Iliniza to Chimborazo, and unites near Tunguragua with the Chambo, which rises near Sangaí. Castelnau and Bates saw pumice floating on the Amazon; it was probably brought from Cotopaxi by the Pastassa.

Crossing the Marañon, and going eastward, we first pass the Huallaga, a rapid river of the size of the Cumberland, coming down the Peruvian Andes from an altitude of eight thousand six hundred feet, and entering the great river nearly opposite the Pastassa. Its mouth is a mile wide, and for a hundred miles up its average depth is three fathoms. In July, August, and September the steamers are not able to ascend to Yurimaguas. Canoe navigation begins at Tinga Maria, three hundred miles from Lima. The fertile plain through which the river flows is very attractive to an agriculturist. Cotton is gathered six months after sowing, and rice in five months. At Tarapoto a large amount of cotton-cloth is woven for export.

The next great tributary from the south is the Ucayali. This magnificent stream originates near ancient Cuzco, and has a fall of .87 of a foot per mile, and a length nearly equal to that of the Negro. For two hundred and fifty miles above its mouth it averages half a mile in width, and has a current of three miles an hour. At Sarayacu it is twenty feet deep. The Ucayali is navigable for at least seven hundred miles. The "Morona," a steamer of five hundred tons, has been up to the entrance of the Pachitéa in the dry season, a distance of six hundred miles, and in the wet season ascended that branch to Mayro. A small Peruvian steamer has recently ascended the Tambo to within sixty miles of Fort Ramon, or seven hundred and seventy-three miles from Nauta.

Leaving the Ucayali, we pass by six rivers rising in the unknown lands of Northern Bolivia: the Javarí, navigable by steam for two hundred and fifty miles; the sluggish Jutahí, half a mile broad and four hundred miles long; the Juruá, four times the size of our Connecticut, and navigable nearly its entire length; the unhealthy, little-known Teffé and Coary; and the Purus, a deep, slow river, over a thousand miles long, and open to navigation half way to its source. Soldan and Pinto claim to have ascended the Javarí, in a steamer, about one thousand miles, and it is said Chandlers went up the Purus one thousand eight hundred miles. The Teffé is narrow, with a strong current. Of all these six rivers, the Purus is the most important. It is probably the Amaru-mayu, or "serpent-river," of the Incas, and its affluents enjoy the privilege of draining the waters of those beautiful Andes which formed the eastern boundary of the empire of Manco Capac, and fertilizing the romantic valley of Paucar-tambo, or "Inn of the Flowery Meadow." The banks of this noble stream are now held by the untamable Chunchos; but the steam-whistle will accomplish what the rifle can not. The Purus communicates with the Madeira, proving the absence of rapids and of intervening mountains.

Sixty miles below the confluence of the Negro, the mighty Madeira, the largest tributary of the Amazon, blends its milky waters with the turbid king of rivers. It is about two thousand miles in length; one branch, the Beni, rising near Lake Titicaca, drains the fertile valleys of Yungus and Apollo, rich in cinchona, chocolate, and gold; the Marmoré springs from the vicinity of Chuquisaca, within fifteen miles of a source of the Paraguay, traversing the territory of the brave and intelligent Moxos; while the Itinez washes down the gold and diamonds of Matto Grosso. Were it not for the cascade four hundred and eighty miles from its mouth, large vessels might sail from the Amazon into the very heart of Bolivia. When full, it has a three-mile current, and at its junction with the Amazon it is two miles wide and sixty-six feet deep. Five hundred miles from its mouth it is a mile wide and one hundred feet deep. It contains numerous islands, and runs in a comparatively straight course. It received its name from the vast quantity of drift-wood often seen floating down. The value of Brazilian commerce with Bolivia by the Madeira was, in 1867, $43,000.[152]