Upon examining the map of a country, we see many of its rivers traveling in opposite directions, and emptying their waters into different seas, although their sources frequently lie in the immediate neighborhood of each other. The springs of the Missouri, which proceed south-east to the Gulf of Mexico, and those of the Columbia, which flow north-west to the Pacific Ocean, are only a mile apart, while those of some of the tributaries of the Amazon, flowing north, and the La Plata, flowing south, are closely contiguous. There is a part of Volhynia, of no considerable extent, which sends off its waters, north and south, to the Black and Baltic seas; while, from the field on which the battle of Naseby was fought, the Avon, Trent, and Nen receive affluents, which reach the ocean at opposite coasts of the island, through the Humber, the Wash, and the Bristol Channel. The field in question is an elevated piece of table-land in the centre of England. The district referred to, where rivers proceeding to the Baltic and the Euxine take their rise, is a plateau about a thousand feet above the level of the sea. The springs of the Missouri and the Columbia are in the Rocky Mountains; and it is generally the case, that those parts of a country from which large rivers flow in contrary directions, are the most elevated sites in their respective districts, consisting either of mountain-chains, plateaus, or high table-lands. There is one remarkable exception to this in European Russia, where the Volga rises in a plain only a few hundred feet above the level of the sea, and no hills separate its waters from those which run into the Baltic. The great majority of the first-class rivers commence from chains of mountains, because springs are there most abundant, perpetually fed by the melting of the snows and glaciers. They have almost invariably an easterly direction, the westward-bound streams being few in number, and of very subordinate rank. Of rivers flowing east, we have grand examples in the St. Lawrence, Orinoco, Amazon, Danube, Ganges, Amour, Yang-tse-Kiang, and Hoang Ho. The chief western streams are the Columbia, Tagus, Garonne, Loire and Neva, which are of far inferior rank to the former. The rivers running south, as the Mississippi, La Plata, Rhone, Volga and Indus, are more important, as well as those which proceed to the north, as the Rhine, Vistula, Nile, Irtish, Lena and Yenisei. The easterly direction of the great rivers of America is obviously due to the position of the Andes, which run north and south, on the western side of the continent, while the chain of mountains which traverses Europe and Asia, from west to east, cause the great number of rivers which flow north and south. In our own island, the chief course of the streams is to the east. This is the case with the Tay, Forth, Tweed, Tyne, Humber and Thames, the Clyde and Severn being the most remarkable exceptions to this direction. The whole extent