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Show TEPPE A D DESERTS. 31 hade the oil beneath from the direct influence of the sunbeams, nnd exhaling, in the interior of the country, at a great distance from the mountains and from t.be ocean, vast quantities of moisture, partly imbibed and pal'tly elaborated :-all these circumstances afford to the fiat part of America a climate which by its humidity and coolne contra t wonderfully with that of Africa. It is to the same ca_u e that we are to attribute the luxuriant vegetation, the magnificent forest , and that abundant lcafiness by which the New Continent is peculiarly characterized. If, therefore, one side of our planet has a moister atmosphere than the other, the consideration of the present condition of things is amply sufficient to explain the problem presented by this inequality. The physical inquirer needs not to clothe the explanation of these phenomena in a mantle of geological myths. He needs not to assume that on our planet the harmonious reconciliation of the destructive conflict of the elements took place at different epochs in the Ea tern and the Western hemispheres ; or that America emerged later than the other parts of the globe from the chaotic watery covering, (19) as an island of swamps and marshes tenanted by alligators and serpents. There is, indeed, a striking similarity between South America and the southern peninsula of the Old Continent in the form of the outline and in the direction of the coasts ; but the nature of the soil, and the relative position of the neighboring masses of land, produce in Africa that extraordinary aridity which over an immense area checks the development of organic life. Four-fifths of South America are situated on the southern side of the Equator; or in a hemisphere which from the greater proportion of sea and from other causes is cooler and moister than our northern half of the globe, (20) to which the larger part of Africa belongs. The breadth of the South American Steppe, measured from east to west, is only a third of that of the African Desert. The Llanos receive the influence of the tropical sea wind, while the African Deserts, being situated in the same zone of latitude as Arabia and the south of Persia, are in contact with strata of air which have blown over warm heat-radiating continents. The venerable and only lately appreciated father of histor;r, I{erodotus, in the true spirit of an enlarged view of na- |