Page:Encyclopædia Britannica, Ninth Edition, v. 4.djvu/23

Rh beasts of burden, all the traffic of Bolivia being carried on by means of them. The vicuna (Gamelus vicugna) is a smaller animal than the guanaco or the llama, and only useful for its fleece. The wool is long and fine, and forms a valuable article of commerce ; it is of a brownish colour, somewhat resembling that of a dried rose leaf ; it has a soft, silky, and close texture, and is well adapted for the manufacture of hats and warm clothing. The vicuna very much resembles the llama and guanaco in its habits and dispositions, but cannot be usefully employed as a beast of burden. It usually fre quents the highest parts of the mountains, is extremely timid, is gregarious, and runs very swiftly. The chinchilla (Chinchilla lanic/era) is also an inhabitant of the moun tainous parts of Bolivia. The skins, however, are of an inferior quality, although larger than those obtained from the northern parts of Chili ; but still they form a very valuable article of commerce, on account of the great fineness and delicacy of their furs. The sheep pasturing in the highlands of Bolivia are supposed to number about seven millions, and in the lower regions of the east horned cattle are very numerous. The eastern or more thickly-wooded parts of Bolivia are inhabited by a variety of wild animals, such as the jaguar and the tapir, which are more or less common in Brazil and the other parts of intertropical America of incon siderable elevation.

The geological structure of the colossal mountains situated in Bolivia has hitherto been very imperfectly examined. We learn from Humboldt, however, that the metalliferous mountains nenr Potosi are principally composed of trachytic porphyries ; and Mr Fcntland discovered trachyte also iu the mountain of Pichu, one of the most elevated of the western Cordillera. In the same chain there likewise exist various volcanic mountains, some of which are in an active state. There is perhaps no part of the world which affords a more interesting field for the investigations of the geologist than Bolivia, not only. on account of the great elevation which it attains, but also from the exhibitions of internal structure presented by volcanic agency and otherwise, not to mention the aid afforded by such inquiries in the prosecution of mining enterprises.

The great variety, extent, and value of the mineral productions of the mountainous districts of Bolivia have given to this part of America an importance and celebrity which it would not otherwise have obtained, and have caused large and populous cities and towns to be built at elevations where the rigours of the climate and the deficient vegetation would otherwise have afforded very few inducements for fixing the abodes of industry. Mining is, however, at the present time in a ruinous state.

Gold is found in considerable quantities in the moun tainous parts of Bolivia ; but, owing to the expense of extracting the metal from the ore, the mines which produce it have not been worked to the extent of which they are capable. In these it is usually found in the form of grains or nodules, or intermixed with antimony, silver, and other substances, and is separated by reducing the whole to a fine powder, and by amalgamation with quicksilver. The mountain of Illimani is believed to contain great quantities of gold, in consequence of that metal having been found in a native state in considerable quantities in the lake of Illimani, situated at its base. In the 17th century, likewise, an Indian found here, at a short distance from the city of La Paz, a mass of native gold, which was said to have been detached from the mountain by the agency of lightning, and which, having been purchased for the sum of 11,269 dollars, was afterwards deposited in the cabinet of natural history at Madrid. But by far the greater part of the gold procured in Bolivia is obtained by means of the lavaderos or gold-washings, in the beds of rivulets, where it is found in the form of grains. The most produc tive of these are the celebrated lavaderos of Tipuani, consisting of streams descending from the snow-capped summits of the Cordillera of Ancuma, situated about sixty leagues to the north-east of the city of La Paz, in the province of Larecaja. The gold is found in the form of grains or pcpitas, at the depth of 10 or 12 yards below the surface, embedded in a stratum of clay of several feet in thickness. The gold-washings at Tipuani were worked in the time of the Peruvian Incas, as is evinced by their tools, which are occasionally found embedded in the alluvial soil, and almost invariably in such situations as prove the most productive. The gold- washings and quartz veins of Cho- quecamata, in the province of Ayopaya in Cochabamba, are also famous, and their yield up to 1847 was valued at 8,000,000. Several districts of the departments of Potosi, Chuquisaca, Santa Cruz, and Tarija, are also rich in gold, but the greater part of the mines formerly worked have now been abandoned, or the known veins have not been explored.

Silver, however, has hitherto been the staple metallic production of Bolivia, and has given to it that celebrity which it has long possessed. In the rich mountains of Potosi alone, according to the records kept at Potosi of the quintas or royal duties from the year 1545 to the year 1800, no less than 823,950,509 dollars wer^ coined dur ing that period ; and if the other produce of the mines be taken into account, it is estimated that not less than 1,647,901,018 dollars must have been obtained from this source alone during those 255 years. The Cerro de Potosi, or argentiferous mountain of Potosi, has a somewhat conical form, resembling a colossal sugar- loaf; its base being about three leagues in circumfer ence, and its summit 15,977 feet above the level of the sea, and 2697 above the level of the great square or plaza of the city of Potosi, which is situated at its base. At the foot of the Cerro is a smaller mountain called Huayna Potosi, or the Younger Potosi, likewise containing silver, but in less abundance than the other, and less accessible, from the numerous springs which there impede the opera tions of mining. The principal mountain has been worked as high up as within 125 feet of its summit. The labours of the miners have been principally confined to the upper half of the mountain, which has been perforated by nume rous excavations, with at least 5000 openings of mines, the greater number of which are however abandoned. The upper part of the mountain is exhausted to a considerable extent of its valuable contents ; but the lov/er part is still in a great measure untouched, as the springs are there more numerous, and the water accumulates in such quantities as materially to interrupt the further progi ess of the miner?;. The mines of Potosi, according to Humboldt, rank next in importance to those of Guanaxuato in Mexico. The exist ence of silver in this place was first accidentally discovered by an Indian in the year 1545, and ever since that time its mines have been worked. In 1858, twenty-two companies were working 46 silver mines and 4 tin shafts in the pro vince of Potosi, and the yield in 1856 amounted to a value of nearly a million dollars. The silver mines of Portugalete, in the province of Chichas, have acquired considerable celebrity on account of the richness as well as quantity of their ores, which yield from 60 to 80 mcrks of silver to the caxon, while those of Potosi only afford about 10 mcrks from the same quantity of ore. Besides these there arc various other silver mines in the province of Chichas, but their value is much dimi nished by the scarcity of water, and by their being situated in an almost desert and unproductive country. The mines of Laurani, in the province of Sicasica in La Paz, once famous, 