316 G. L. COLLIE PLATEAU OF BRITISH EAST AFRICA 



walls is in a youthful stage, on the whole, and the indications are that 

 the Rift is comparatively recent in origin. 



FATE OF TEE RIFT VALLEY ^ 



Since the Eift is a valley of accumulation, it might become filled with 

 detritus in the course of time, but it would take long to obliterate it by 

 this method. Erosion, however, is removing the divide which separates 

 it from the Victoria basin, and that with rapidity. When this divide is 

 taken away, the warm, moisture-laden winds from the Congo region, 

 which now precipitate their contents on the western slope of the divide, 

 will sweep across the Eift Valley and yield their rainfall to the eastern 

 escarpment. Streams will then flow across the present Eift to the Nile 

 basin, and the Eift Valley will be added to that great system of drainage. 

 The east wall will then be attacked and retreat until a suitable gradient 

 has been established to the Nile. By that time the Eift will largely dis- 

 appear, perhaps leaving no trace of its existence. All that may be left 

 to tell the story of its greatness and uniqueness will be the records of 

 those who saw it in its pristine days. 



