Northward The Granitic Chain Of The Silla De Caracas And Porto Cabello Are Separated From The Llanos By A Screen Of Mountains That Are Schistose Between Villa De Cura And Parapara, And Calcareous Between The Bergantin And Caripe.

I was no less struck by this absence of blocks on the banks of the Amazon.

La Condamine affirms that from the Pongo de Manseriche to the Strait of Pauxis not the smallest stone is to be found. Now the basin of the Rio Negro and of the Amazon is also a Llano, a plain like those of Venezuela and Buenos Ayres. The difference consists only in the state of vegetation. The two Llanos situated at the northern and southern extremities of South America are covered with gramina; they are treeless savannahs; but the intermediate Llano, that of the Amazon, exposed to almost continual equatorial rains, is a thick forest. I do not remember having heard that the Pampas of Buenos Ayres or the savannahs of the Missouri* and New Mexico contain granitic blocks. (* Are there any isolated blocks in North America northward of the great lakes?) The absence of this phenomenon appears general in the New World as it probably also is in Sahara, in Africa; for we must not confound the rocky masses that pierce the soil in the midst of the desert, and of which travellers often make mention, with mere scattered fragments. These facts seem to prove that the blocks of Scandinavian granite which cover the sandy countries on the south of the Baltic, and those of Westphalia and Holland, must be traced to some local revolution.

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