In proportion to its length the area of the coast line is small, as the Andes here run closer to the shore than in Ecuador, especially in the central portion, where spurs from the main range sometimes end in bold bluffs rising 500 feet from the sea. In general the width of the coast land varies from 20 to 50 miles, in places reaching to 100. Unfortunately the coast is slightly indented by gulfs and bays and therefore has few good harbors. THE SIERRA In the sierra country we find the greatest development of the mountain system of the Andes attained in its entire course. For the most part it here consists of three ranges, the Maritime, the Central, and the East Cordillera. The first two, near together, are regarded as of similar origin, separated during ages by the action of water. They include volcanoes and mineral springs; and in some parts of the lofty region between the two, cold alpine lakes, sources of coast rivers and also of Amazon tributaries. =The Maritime Cordillera= is not connected with the coast ranges of Chile, but is a continuation of that cordillera which forms the eastern limit of the coastal Chilian desert and the western boundary of the great Bolivian plateau. In Bolivia and Southern Peru it is a volcanic chain with some peaks of great height, over 20,000 feet. Though generally quiescent, one volcano in Peru south of Arequipa in the year 1700 erupted continuously for two weeks. El Misti, altitude 19,200 feet, above Arequipa is well known. From the summit a little smoke may be seen in the depths of the crater. The volcanoes seem to have some connection with earthquakes, with which this region is often affected. Though the quakes are mostly slight tremors, severe shocks occur; 70 of a destructive nature have been reported since 1570. The worst, which in 1746 completely destroyed Callao, was followed by 220 shocks within 24 hours. The city was overwhelmed by a tidal wave 80 feet high from which not half a dozen inhabitants escaped. The earthquake of 1868, which was felt over most of South America, half destroyed Arequipa, and tidal waves swept over Arica and Iquique. In 1877 nearly half of the southern ports were submerged; in 1906 a good portion of Valparaiso, Chile, was laid in ruins, a fate within a period of 12 months shared by San Francisco and by Kingston, Jamaica. At about 10° S. Lat. the Maritime Cordillera separates into two ranges for a distance of 100 miles, the Cordillera Negra, and the Cordillera Blanca, the two enclosing the Huailas Valley; north of where the Santa River breaks through toward the coast, the Black Range begins to subside, the Maritime continuing to Ecuador in a single chain.