336 THE CORDILLERAS. 



The surface of the great lake of Titicaca the largest piece 

 of fresh water in South America is 12,795 feet above the 

 Pacific ; an elevation greater than that of the highest peaks of 

 the Pyrenees. In the neighbourhood of this lake, remains 

 exist which speak of the advanced state of civilization of the 

 inhabitants before the appearance of the Incas, with whose 

 latter history alone we are acquainted. So completely 

 is the lake surrounded by mountains, that, though fed by 

 numerous streams, not the smallest rivulet escapes to find its 

 way either into the Pacific or Atlantic. One large river, 

 however, the Desaguadero, flows out of its south-west corner, 

 and disappears in the swampy Lake Aullagas in the south of 

 Bolivia. Its superabundant water must, therefore, be taken 

 off by evaporation, excessive in that elevated region. High 

 above it, amid chilling mists and biting storms of driving 

 snow, are found the silver-mines of Potosi and Pasco. 



' However, before we wander further amid the giddy preci- 

 pices and snow-capped summits of this mighty range of moun- 

 tains, we will descend for a time to the lower world, and 

 glance round its southern extremity and along its western 

 shores, bathed by the waters of the wide-stretching Pacific. 



