The desert of Atacama, the largest of all those in South America, occupies a wide belt of plateaus between the shores of the Pacific and the high rampart of the Andes, which separates Bolivia from the Argentine Republic. This expanse of reddish-colored rocks, and crescent-shaped shifting sand-hills, is so repulsively desolate a place that the conquerors of Chili, whether Incas or Spaniards, never made up their minds to venture into it, in going along the sea-coast; they have been obliged to pass far into the interior, by the plateaus of Bolivia, and to twice cross the Andes before entering the Chilian valleys. Not long since, men of science were the only travelers who dared to enter the desert of Atacama. Nevertheless this formidable-looking country also possesses, like the _pampa_ of Tamarugal, great natural riches, which will not fail to summon the labor of man and all the progress of civilization to these desolate regions. Besides salt and saltpetre, this desert produces guano--that is, heaps of the almost exhaustless droppings of all the sea-birds which settle down in clouds upon the seashore. During the course of centuries the ordure has accumulated into perfect rocks which the sun dries up, and the surface of which is but rarely softened by rain. These masses of detritus, which are, to all appearance, useless upon these barren shores, are life itself to the countries of England, France, and Belgium, which have become exhausted by the extent of cultivation; and, consequently, this substance constitutes a most important element of national commerce. II.--THE SEA THE PRIMITIVE OCEAN --G. HARTWIG The greatest of all histories, traced in mighty characters by the Almighty Himself, is that of the earth-rind. The leaves of this great volume are the strata which have been successively deposited in the bosom of the sea or raised by volcanic powers from the depths of the earth; the wars which it relates are the Titanic conflicts of two hostile elements, water and fire, each anxious to destroy the formations of its opponent; and the historic documents which bear witness to that ancient strife lie before us in the petrified or carbonified remains of extinct forms of organic existence--the medals of creation.