If, then, the true Egypt be the tract that we have described—­the Nile valley, with the Fayoum and the Delta—­the lily stalk, the bud, and the blossom—­we can well understand how it came to be said of old, that “Egypt was the gift of the river.”  Not that the lively Greek, who first used the expression, divined exactly the scientific truth of the matter.  The fancy of Herodotus saw Africa, originally, doubly severed from Asia by two parallel fjords, one running inland northwards from the Indian Ocean, as the Red Sea does to this day, and the other penetrating inland southwards from the Mediterranean to an equal or greater distance!  The Nile, he said, pouring itself into this latter fjord, had by degrees filled it up, and had then gone on and by further deposits turned into land a large piece of the “sea of the Greeks,” as was evident from the projection of the shore of the Delta beyond the general coast-line of Africa eastward and westward; and, he added, “I am convinced, for my own part, that if the Nile should please to divert his waters from their present bed into the Red Sea, he would fill it up and turn it into dry land in the space of twenty thousand years, or maybe in half that time—­for he is a mighty river and a most energetic one.”  Here, in this last expression, he is thoroughly right, though the method of the Nile’s energy has been other than he supposed.  The Nile, working from its immense reservoirs in the equatorial regions, has gradually scooped itself out a deep bed in the sand and rock of the desert, which must have originally extended across the whole of northern Africa from the Atlantic to the Red Sea.  Having scooped itself out this bed to a depth, in places, of three hundred feet from the desert level, it has then proceeded partially to fill it up with its own deposits.  Occupying, when it is at its height, the entire bed, and presenting at that time the appearance of a vast lake, or succession of lakes, it deposes every day a portion of sediment over the whole space which it covers:  then, contracting gradually, it leaves at the base of the hills, on both sides, or at any rate on one, a strip of land fresh dressed with mud, which gets wider daily as the waters still recede, until yards grow into furlongs, and furlongs into miles, and at last the shrunk stream is content with a narrow channel a few hundred yards in width, and leaves the rest of its bed to the embraces of sun and air, and, if he so wills, to the industry of man.  The land thus left exposed is Egypt—­Egypt is the temporarily uncovered bed of the Nile, which it reclaims and recovers during a portion of each year, when Egypt disappears from view, save where human labour has by mounds and embankments formed artificial islands that raise their heads above the waste of waters, for the most part crowned with buildings.