598 DIVEKSION OF THE NILE. 



die and Lower Egypt, the conversion of that part of the valley 

 into a desert, and the extinction of its imperfect civilization, if 

 not the absolute extirpation of its inhabitants. This is the calamity 

 threatened by the Abyssinian princes and the ferocious Portu- 

 guese warrior, and feared by the Sultans of Egypt. Beyond these 

 immediate and palpable consequences neither party then looked ; 

 but a far wider geograpliical area, and far more extensive and 

 various human interests, would be affected by the measure. The 

 spread of the Nile during the annual inundation covers, for many 

 weeks, several thousand square miles with water, and at other 

 seasons of the year pervades the same and even a larger area 

 with moisture by infiltration. The abstraction of so large an 

 evaporating surface from the southern shores of the Mediter- 

 ranean could not but produce important effects on many mete- 

 orological phenomena, and the humidity, the temperature, the 

 electrical condition and the atmospheric currents of I^ortheastern 

 Africa might be modified to a degree that would sensibly affect 

 the chmate of Europe. 



The Mediterranean, deprived of the contributions of the Nile, 

 would require a larger supply, and of course a stronger current, 

 of water from the Atlantic through the Straits of Gibraltar; 

 the proportion of salt it contains would be increased, and the 

 animal life of at least its southern borders would be consequently 

 modified ; the current which winds along its southern, eastern 

 and northeastern shores would be diminished in force and vol- 

 ume, if not destroyed altogether, and its basin and its harbors 

 would be shoaled by no new deposits from the highlands of inner 

 Africa. 



In the much smaller Red Sea, more immediately perceptible, 

 if not greater, effects would be produced. The deposits of slime 

 would reduce its depth, and perhaps, in the course of ages, divide 

 it into a northern inland and a southern open sea, the former of 

 which, receiving no supply from rivers, would, as in the case of 

 the northern part of the Gulf of California, soon be dried up by 

 evaporation, and its whole area added to the Africo-Arabian 

 desert ; the waters of the latter would be more or less freshened, 

 and their immensely rich marine fauna and flora changed in char- 

 acter and proportion, and, near the mouth of the river, perhaps 

 even destroyed altogether ; its navigable channels would be 



