There are localities which have been visited by adventurous explorers, especially in Chili and Peru, where ruins have been found, and various monuments of antiquity examined, of vast interest to archæologists, but of which scarcely more than their mere existence is recorded. Some of these ruins are believed to antedate by centuries the period of the Incas, and are supposed to be the remains of tribes which, judging from their pottery and other domestic utensils, were possibly of Asiatic origin. Comparatively few travelers have visited Lake Titicaca, in the Peruvian Andes, with its sacred islands and mysterious ruins, from whence the Incas dated their mythical origin. The substantial remains of some grand temples are still to be seen on the islands near the borders of the lake, the decaying masonry decked here and there with a wild growth of hardy cactus. This remarkable body of water, Lake Titicaca, in the mountain range of Peru, lies more than twelve thousand feet above the level of the Pacific; yet it never freezes, and its average depth is given as six hundred feet, representing an immense body of water. It covers an area of four thousand square miles, which is about four fifths as large as our own Lake Ontario, the average depth being about the same. Titicaca is the largest lake in the world occupying so elevated a site.
The population of South America is mostly to be found on the coast, and is thought to be about thirty-five millions, though, all things considered, we are disposed to believe this an overestimate. There are tribes far inland who are not brought in contact with civilization at all, and whose numbers are not known. The magnitude and density of the forests are remarkable; they cover, it is intelligently stated, nearly two thirds of the country. The vegetation, in its various forms, is rich beyond comparison. Professor Agassiz, who explored the valley of the Amazon under the most favorable auspices, tells us that he found within an area of half a mile square over one hundred species of trees, among which were nearly all of the choicest cabinet and dye woods known to the tropics, besides others suitable for shipbuilding. Some of these trees are remarkable for their gigantic size, others for their beauty of form, and still others are valuable for their gums and resins. Of the latter, the india-rubber tree is the most prolific and important known to commerce. From Brazil comes four fifths of the world's supply of the raw material of rubber.