y retained the name of Antis or Andes. In the time of the
Incas, both chains were called Ritisuyu (Snow-Districts). The Spaniards,
on the invasion of the country, advancing from the sea-coast, first
arrived at the western mountains, and to them they gave the name of
_Cordillera_, the term commonly employed in the Spanish language, to
designate any mountain chain. Most of the earlier travellers and
topographists named the western chain the _Cordillera de los Andes_, and
regarded it as the principal chain, of which they considered the eastern
mountains to be merely a branch. To the eastern range of mountains they
gave the name of _Cordillera Oriental_. I will here strictly observe the
correct denominations, calling the western chain the Cordillera, or the
coast mountains; and the eastern chain the Andes, or the inner
Cordillera.

These two great mountain chains stand in respect to height in an inverse
relation one to the other; that is to say, the greater the elevation of
the Cordillera, the more considerable is the depression of the Andes. In
South Peru the ridge of the Cordillera is considerably lower than that
portion of the Andes which stretches through Bolivia. The medium height
of the Cordillera in South Peru is 15,000 feet above the sea; but here
and there particular points rise to a much more considerable elevation.
The medium height of the Andes is 17,000 feet above the sea. In central
Peru the Cordillera is higher than the Andes. There the altitude of the
latter along the body of the chain is 13,000 feet above the sea: on the
ridge there are a few points some hundred feet higher. Between Pasco
and Loxas the average height of the Cordillera is between 11,000 and
12,000 feet above the sea; and the average elevation of the Andes at the
corresponding point is about 2000 feet lower.

The passes do not run through valleys, but always over the ridges of the
mountains. The highest mountain passes are the Rinconada (16,452 feet
above the sea); the Piedra Parada (16,008 feet); the Tingo (15,600
feet); the Huatillas (14,850 feet); the Portachuelo de la Viuda (14,544
feet); the Altos de Toledo (15,530 feet); and the Altos de los Huesos
(14,300 feet). In both chains there are innumerable small lakes; these
are met with in all the mountain passes, and most of them are the
sources of small rivers.

Both the mountain chains, as well as their lateral branches, are rich in
metallic produce; but in the principal mountains gold i