In the interior of South America, between the parallels of 2° and 4° north lat., lies a wooded plain inclosed by four rivers, the Orinoco, the Atabapo, the Rio Negro, and the Cassiquiare. Here we find granitic and syenitic rocks, which, like those of Caicara and Uruana, are covered with colossal symbolical figures of crocodiles, tigers, utensils of domestic use, signs of the sun and moon, &c. This remote portion of the earth is at present wholly uninhabited throughout an extent of more than 8000 square miles. The neighbouring tribes, who occupy the lowest place in the scale of humanity, are naked wandering savages, who could not possibly have carved hieroglyphics in stone. A whole range of these rocks covered with symbolical signs may be traced from Rupunuri, Essequibo, and the mountains of Pacaraima, to the banks of the Orinoco and of the Yupura, extending over more than eight degrees of longitude. These carvings may belong to very different periods of time, for Sir Robert Schomburgk even found on the Rio Negro representations of a Spanish galliot,[HR] which must necessarily have been of a date subsequent to the beginning of the sixteenth century, and that in a wilderness where the inhabitants were probably as rude then as they now are. But it must not be forgotten, as I have already elsewhere observed, that nations of very different descent, but in similarly uncivilized conditions, possessed of the same disposition to simplify and generalize outlines, and urged by identical inherent mental tendencies, may be led to produce similar signs and symbols.[HS]