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the commencement of this process is seen at the influx of every stream. Thus also is the habitable surface of the earth encreased, in these cases, as it is on the sea shores; and that which was the dwelling of fishes becomes a place for man. In the higher valleys of hilly countries, the steep sides of the hills become thus fitted for the plough ; while the lodgment of alluvia in their lower parts raises the surface, and produces a fertile plain where there was once a barren declivity. Thus also, in the lower plains, the levels are enlarged; while additional fertility is conferred by the finer materials which the waters bring down. Thus has been produced the fertile district of Egypt. Divest it of tbe mud which interior Africa has supplied, and nothing remains but a steep rocky valley, rolling the Nile along, and admitting the sea within its entrance. Hence the fertile plains of Lom bardy, and the extensive tracts which attend the Plata, the Oroonoko, the Amazon, and the Hudson. Moun tains useless to man, nearly useless to animals, covered with a scanty vegetation, thus become the seats of nations, regions of fertility, and wealth, and power. The connexion between the lowest plains and the sestuaries in which they terminate, is so intimate, that the one is but a part of the other: the limit is a “ punctum fluens,” where that which is now sea is shortly destined to become land. In these cases, the submarine alluvia, first appearing under the form of banks, and lastly under that of islands, extend the solid plain. Whether in lakes or in the sea, the general process is the same. The Wolga enters the Caspian by seventy mouths, the produce of islands afterwards united, and of which fresh ones are forming every day. Thus the Sunderbunds first appear as islands, which, uniting, determine a new aperture for the Ganges, or