... Negro verbindet. Humboldt untersuchte den Casiquiare während seiner Orinocoreise, um diese Verbindung (published in 1812) of the river Casiquiare, which connects the Orinoco and the Rio Negro. Humboldt studied (published in 1812) of the river Casiquiare, which connects the Orinoco and the Rio Negro. Humboldt studied ..."