1 68 PHYSICAL SCIENCE BK. iv 



retort with a verse from his favourite Ovid ? 1 who 

 says : 



Nor do the herbs make supplication to the rain-god Jupiter. 



3 If one could only ascertain at what point in the 

 course of the river the rise begins, the causes of the 

 rise would also be discovered. As it is, the river 

 wanders through great deserts, spreads out into 

 marshes, among many scattered tribes, before it 

 is for the first time after its wandering, mazy course 

 gathered into one near Philae. Philae is a rugged 

 island, precipitous on all sides ; it is surrounded by 

 the two branches of the river before they unite to 

 form the one river which henceforth bears the 

 designation Nile. The whole city of Philae is 

 surrounded by the Nile, which after leaving 

 Ethiopia is a large rather than rapid river. 2 Next 

 in its course are the sandy deserts through which 



4 passes the trade route to the Red Sea. 2 After 

 that the Nile enters the Cataracts, a spot famous 

 for a wonderful sight. The river rises over high 

 crags that are at several points jagged. The 

 opposing rocks break up its course and rouse its 

 utmost force ; as it struggles through the narrows, 

 swirls show the points where it conquers or is con 

 quered. A smooth channel had hitherto conducted 

 its waters without uproar. Here for the first time 

 they are roused, and the turbulent cataract leaps 

 down through the narrow passage quite unlike its 



5 former self. Up to that point the stream was thick 

 and muddy. But once it enters the craggy gorge 

 it breaks into foam. Its colour is no longer the 

 natural one, but derived from the ground through 



1 The quotation is really from Tibullus. 

 2 The text is very uncertain. 



