Note 53 — THE CATARACTS OF THE ORINOCO.

p. 209.—“Across the peaceful ocean arm, which fills the wide valley between the American shore and Western Africa.”

The Atlantic Ocean, from the 23d degree of South to the 70th degree of North latitude, has the form of an excavated longitudinal valley, in which the salient and re-entering angles are opposite to each other. I first developed this idea in my “Essai d’un Tableau géologique de l’Amérique méridionale,” printed in the Journal de Physique, T. liii. p. 61. (Geognostische Skizze von Südamerika, in Gilbert’s Annalen der Physik, Bd. xvi. 1804, S. 394–449.) From the Canaries, and especially from the 21st degree of North latitude and the 23d degree of West longitude, to the North-East coast of South America, the surface of the sea is usually so calm, and the waves so gentle, that an open boat might navigate in safety.