886 NOETH-EAST AFRICA. lived in a climate different from that of our days. Oscar Fraas goes even so far as to assert positively that " the desert was not yet." * Such an assertion is doubtless exaggerated ; but it is at the same time certain that water was formerly far more abundant in the now arid valleys of the Libyan and eastern uplands. In many places the traces may still be observed of ancient cascades, which flowed perennially in these now all but waterless regions. At that epoch the woodlands still yielded sufficient timber to work the mines, which now lie idle for lack of fuel. To bake their bread, the fellahin use nothing but cakes of dung mixed with mud and dried in the sun. But while the supposition of a considerable change in the Egyptian climate since the dawn of history may be accepted as highly probable, the statements of several travellers and meteorologists regarding certain climatic modifications, supposed to have occurred since the beginning of the last century, cannot be admitted as yet demonstrated. It is often asserted that the plantations of mul- berries and other trees made by Mohammed Ali have directly tended to bring about an increase of moisture, and the great progress in agriculture made during the present generation is supposed to have had a like result. But these statements rest entirely on personal impressions, which have not yet been confirmed by systematic observations. It may also be questioned whether the local climate of the Isthmus of Suez has really undergone any slight modification at all since the construction of the fresh- water and marine canals. These works, however gigantic in the eyes of man, still remain too insignificant, compared with the extent of the surrounding seas, to have produced any appreciable change, except perhaps in the immediate vicinity of the canal. They can scarcely have had any general influence in moderating the extremes of heat and cold, rendering the atmosphere more humid, or increasing the abundance and duration of the rainfall. Flora of Egypt. Few regions of the globe beyond the polar zones possess a flora so poor in vegetable species as that of Egypt. The uniformity of its plains, the lack of variety in the chemical composition of its soil, the absence of well- watered hills and uplands, the monotonous character of the agriculture, everything tends to produce this result. Thousands of years ago the peasantry had already destroyed the forests, unless the tracts be regarded as such which are still partly covered with the 8unt (^acacia Nilotica), the formerly sacred tree used by the Israelites to build the Ark of the Covenant. So valuable is timber in Egypt that the boatmen use cow-dung kneaded with clay and chopped straw instead of planks to deck their barges. Taken as a whole, the Egyptian flora presents a mixture of European, Asiatic, and African species. But the last mentioned are the most prevalent, at least beyond the region of the delta. The characteristic aspect of the Egyptian land- • " Au8 dem Orient." • 4
