Page:Encyclopædia Britannica, Ninth Edition, v. 18.djvu/704

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672 P E E U tides. Sea-lions (Otaria forsteri) are common on the rocky islands and promontories. These large creatures frequent particular islets for the purpose of breathing their last, the wounded or aged being helped there by their companions. The Maritime Cordillera, overhanging the Peruvian coast, contains a long line of volcanic mountains, most of them inactive, but their presence is probably connected Earth- with the frequent and severe earthquakes, especially in quakes, the southern section of the coast. Since the year 1570 there have been seventy violently destructive earthquakes recorded on the west coast of South America, but the register is of course incomplete in its earlier part. The most terrible was that of 1745, which destroyed Callao. There had been subterranean noises for some days previ ously ; the first shock was at 10.30 P.M. on 28th October, and there were 220 shocks in the following twenty-four hours. The town was overwhelmed by a vast wave, which rose 80 feet ; and the shocks continued until the following February. On 13th August 1868 an earthquake nearly destroyed Arequipa, and great waves rolled in upon the ports of Arica and Iquique. On 9th May 1877 nearly all the southern ports were overwhelmed. These fearful catastrophes are in greatest force where there are vol canoes, whether active or extinct, in the vicinity. That of 1877 had its origin in the volcanic mountains near the frontier of Peru and Bolivia, and spent its chief fury near its centre of origin, gradually working itself out as it went north. Usually the line of disturbance is meridional and along the coast, but in some instances the line takes a seaward direction at an angle with the mountain-chains. The The most important part of Peru is the region of the sierra. cordilleras of the Andes divided into "puna" or lofty unin habited wilderness, and "sierra" or inhabitable mountain slopes and valleys. This great mountain-system, running south-east to north-west with the line of the coast, consists of three chains or cordilleras. The two chains which run parallel, and near each other on the western side, are of identical origin, and have been separated by the action of water during many centuries. On these chains are the volcanoes and many thermal springs. The narrow space between them is for the most part, but not always, a cold and lofty region known as the " puna," containing alpine lakes, the sources of the coast-rivers. The great eastern chain, rising from the basin of the Amazon and forming the inner wall of the system, is of distinct origin. These three chains are called the Maritime Cordillera, the Central Cordillera, and the Andes. Paz Soldan and other Peruvian geographers give the name of Andes, par excellence, to the eastern cordillera. Maritime The Peruvian Maritime Cordillera contains a regular chain of volcanic peaks overlooking the coast-region of Tarapaca, which attain a height of 16,000 to 18,000 feet. Chief among them are the snowy peak of Lirima over the ravine of Tarapaca, the volcano of Isluga overhanging Camilla, the unmeasured peak of Sehama, and Tacora near the Bolivian frontier. In rear of Moquegua there is a group of volcanic peaks, clustering round those of Ubinas and Huaynaputina. A great eruption of Huaynaputina commenced on 15th February 1600 and continued until the 28th. An incessant rain of fine white sand was poured over the surrounding country for a distance of 40 miles, accompanied by a mighty subterraneous roaring sound. But generally these volcanoes are quiescent. Farther north the Misti volcano rises over the city of Arequipa in a perfect cone to a height of over 18,000 feet, and near its base are the hot sulphur and iron springs of Yura. As the maritime chain advances northward it fully main tains its elevation. The peak of Sarasara, in Parinacochas (Ayacucho), is 19,500 feet above the sea, and in the mountains above Lima the passes attain a height of more than 15,000. In latitude 10 S. the maritime chain separates into two branches, which run parallel to each other for 100 miles, enclosing the remarkable ravine or Callejon de Huaylas, the eastern or main branch being known as the Cordillera Nevada and the western as the Cordillera Negra. On the Nevada the peak of Huascan reaches a height of 22,000 feet, according to the trigo nometrical measurement of the railway engineer Hindle. The Huandoy peak, above Carhuaz, reaches to 21,088 feet ; the Hualcan peak, overhanging the town of Yungay, is 19,945 feet high; and most of the peaks in this part of the chain reach a height of 19,000 feet. During the rainy season, from October to May, the sky is generally clear at dawn, and the magnificent snowy peaks, with .sharply -defined outlines, stand out in lovely contrast to the deep -blue background. But as the day advances the clouds collect, and the whole is shrouded in a dense veil. In most parts of the Peruvian Andes the line of perpetual snow is at 16,400 feet above the sea; but on the Cordillera Nevada, above the Callejon de Huaylas, it sinks to 15,400 feet. This greater cold is obviously caused by the intervention of the Cordillera Negra, which intercepts the warmth from the coast. As this lower chain does not reach the snow- line, the streams rising from it are very scantily supplied with water, while the Santa, Pativilca, and other coast-rivers which break through it from sources in the snowy chain have a greater volume from the melted snows. At the point where the river Santa breaks through the Cordillera Negra that range begins to subside, while the Maritime Cordillera continues as one chain to and beyond the frontier of Ecuador. The Central Cordillera is the true water-parting of the Centr system. No river, except the Maranon, breaks through it Cor - either to the east or west, while more than twenty coast- streams rise on its slopes and force their way through the maritime chain. The Central Cordillera consists mainly of crystalline and volcanic rocks, on each side of which are aqueous, in great part Jurassic, strata thrown up almost vertically. In 14 30 S. lat. the central chain is connected with the Eastern Andes by the transverse mountain-knot of Yilcafiota, the peak of that name being 17,500 feet above the sea. The great inland basin of Lake Titicaca is thus formed. The central chain continues to run parallel with the Maritime Cordillera until, at Cerro Pasco, another transverse knot connects it with the Andes in 10 30 S. lat. It then continues northward, separating the basins of the Maranon and Huallaga ; and at the northern frontier of Peru it is at length broken through by the Maranon flowing to the eastward. The Eastern Andes is a magnificent range in the southern Easte part of Peru, of Silurian formation, with talcose and clay Ande slates, many quartz veins, and eruptions of granitic rocks. Mr Forbes says that the peaks of Illampu (21,470 feet) and Illimani (21,040 feet) in Bolivia are Silurian and fossiliferous to their summits. The eastern range is cut through by six rivers in Peru, namely, the Maranon and Huallaga, the Perene, Mantaro, Apurimac, Vilcamayu, and Paucartambo, the last five being tributaries of the Ucayali. The range of the Andes in south Peru has a high plateau to the west and the vast plains of the Amazonian basin to the east. The whole range is highly auriferous, and the thickness of the strata is not less than 10,000 feet. It is nowhere disturbed by volcanic eruptions, except at the very edge of the formation near Lake Titicaca, and in this respect it differs essentially from the Maritime Cordil lera. To the eastward numerous spurs extend for varying distances into the great plain of the Amazons. It is here that the majestic beauty of the Andean scenery is fully realized : masses of dark mountains rise for thousands of feet, with their bases washed by foaming torrents and their