Note:  Do not rely on this information. It is very old.

Rio Negro

Rio Negro, (1) rising in the south-east of Colombia, flows east into Venezuela, south into the Amazonas, and then east and south-east to the Maranon, with a course of 1,350 miles, in which it forms many lagoons. Its tributary, the Casiquiene, is the medium of communication between the Amazon and Orinoco. (2) A river of Argentina, has a course of 500 miles to the Atlantic, and is navigable for small vessels. It has great saline lakes.