293 



From these circumstances we may infer that, al- 

 though the rains continue three months in Abyssinia, it 

 is only during about two months that the rise of the Nile 

 is rapid, and its current greatly accelerated ; in which 

 time, no doubt, great quantities of alluvion were 

 brought down by its current, and deposited at its 

 mouth. 



3rdly. It is necessary to examine the tides of the 

 Mediterranean sea, with a view to their influence on 

 the current of the river. 



On this subject there seems to he a difference of 

 opinion. Herodotus mentions the ebbing and flowing 

 of the tides ; which, he observes " may be seen every 



Mr. Renndl says, that "the w r aters of the North 

 Atlantic eternally flow into the Mediterranean."! 

 This, he seems to suppose, is a consequence of the 

 Mediterranean being lower than that of the Red Sea. 

 But if " the waters of the North Atlantic eternally flow 

 into the Mediterranean," it is almost impossible that 

 there can be such a thing as an ebbing of its waters : 

 but setting the question of the level of the Red Sea 

 and Mediterranean a^ide, we can scarcely conceive 

 tint the evaporation of the waters, from the intensity 

 of heat, in those regions, can so far exceed the quanti- 

 ties of water poured into that sea on all sides, as to 

 occasion a current constantly setting in from the Atlan- 



* Po'ym 198. 



t Rennell's Herodotus, page 4-76. 





