WE DIG IN 39 



"It is a curious lake," he observed. "Have you 

 any idea how it is fed? " 



"That is easy," I repHed. "Rains are caught in 

 the crater which forms its bowl." 



"No, that theory won't hold. There is too little 

 slope on the crater to catch much water; what is 

 caught would evaporate quickly; and by the end 

 of the dry season you'd find your lake gone." 



"Springs, then," suggested Osa. 



"Wrong again," Percival replied. "This is the 

 highest point for hundreds of miles and you wouldn't 

 get all^that water from imderground springs. What I 

 believe is that it is fed from other lakes at higher 

 levels way up in Abyssinia that discharge their water 

 through undergroimd rivers which find their way 

 here." 



"You told me," he added, "that when you were 

 here before you noticed a net loss by watermarks of 

 three feet each year. If we could find this other lake, 

 you'd find that it too was lowering at the same rate ; 

 and perhaps your great-great-grandchildren will find 

 no lake here at all or else only a rhino wallow." 



We couldn't, however, imagine any such fate for 

 this beautiful body of water, probably first visited by 

 . an old missionary two hundred years ago who wrote 

 that old yellowing book, which had originally aroused 

 our curiosity and led to the lake's latest discovery. 

 No, we simply would not believe that the lake would 



