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NORTH-EAST AFRICA.
survive of the former Egyptian, Roman, and Arab works. In some places, and notably near Suez, the dykes, built with such hard stone that the Arabs take them for natural rocks, rise here and there some 18 or 20 feet above the plains.
It is probable that to a barrage, the remains of which are still visible, the ground-sill of Gisr owes its Arabic name of "dyke."
While the mud and sands were obliterating the monuments of the Pharaohs, Ptolemies, Trajan, and Amru, the Sultans of Constantinople, after the reduction of Egypt, frequently entertained the idea of renewing the works of their predecessors.