[114] Humboldt speaks of this as an active volcano, "from which detonations are heard almost daily." We heard nothing. It is possible that he meant Guamani.
[115] The Chasuta Indians, Herndon says, eat musquitoes that they catch on their bodies with the idea of restoring the blood which the insect has abstracted.
[116] Sometimes called yuca dulce, or sweet yuca, to distinguish it from the yuca brava, or wild yuca, the mandioca of the Amazon, from which farina is made. The yuca is the beet-like root of a little tree about ten feet high. It is a good substitute for potatoes and bread.
[117] Vanilla belongs to the orchid family, and is the only member which possesses any economical value. It is a graceful climber and has a pretty star-like flower.
[118] In Peru, the liquor made from yuca is called masato.
[119] Rock-salt is found on both sides of the Andes. "The general character of the geology of these countries would rather lead to the opinion that its origin is in some way connected with volcanic heat at the bottom of the sea."—Darwin's Observations, pt. iii., p. 235.
[120] "The Napo (Herndon was told) is very full of sand-banks, and twenty days from its mouth (or near the confluence of the Curaray) the men have to get overboard and drag the canoes!"—Report, p. 229.
[121] The chief difficulty throughout the Upper Amazon is in getting the Indians to concentrate along the bank. But honorable dealing would accomplish this in time.
[122] Its actual source is the Rio del Valle, which runs northward through the Valle Vicioso. Its longest tributary, the Curaray, rises only a few miles to the south in the Cordillera de los Mulatos. The two rivers run side by side 4° of longitude before meeting. Coca, the northern branch, originates in the flanks of Cayambi. The Napo and its branches are represented incorrectly in every map we have examined. The Aguarico is confounded with the Santa Maria and made too long, and the Curaray is represented too far above the mouth of the Napo. There are no settlements between Coca and Camindo.
[123] From specimens of sand which we obtained at different points in descending the river, we find that at Coca it contains 17.5 per cent. of pure quartz grains, the rest being colored dark with augite: at the mouth of the Napo there is 50 per cent. of pure quartz, the other half being light-colored and feldspathic.