“Notwithstanding the slow rate at which commerce and civilisation advance in the interior of South America, the opening up of routes of communication is becoming daily of more importance, and is exciting greater interest among the inhabitants. Some of the mighty rivers of that continent might seem to have been made by nature's hand expressly for steam navigation, being so wide and deep, and flowing with so gentle and equable a descent, as to allow vessels of considerable size to reach the very foot of the mountains whence they take their rise; such are the Amazons, the Magdalena, and the Plata, with its tributary the Paraná; while others, of scarcely inferior volume, such as the Orinoco, the Rio Negro, the Madeira, and the Cauca (the main tributary of the Magdalena), are navigable for a considerable distance in their lower and upper parts, but towards the middle of their course are beset by rapids and cataracts, which can only be ascended, even by small boats, with infinite trouble, risk, and delay. In the case of the Orinoco and Rio Negro, the cataracts occupy so short a space, the actual fall is so slight, and the nature of the ground is such, that the obstructions might be easily turned or avoided by a navigable canal or a railroad, neither of which is likely to be constructed until the exigencies of commerce or colonisation shall make it an imperative necessity.