46 Transactions of the South African Philosophical Society. 



cut downwards, leaving the old bevel-surface entire except for the 

 canon-like gorge through which the rivers run. The farms along the 

 main river are divided into two kinds, one lying on the river-level 

 and utilising the narrow strip of alluvium, the other lying in wide 

 open plains some 800 feet above the other. Communication between 

 the two sets of farms can only be made at a few points, and then the 

 road or footpath is extremely precipitous. Above the plains the 

 mountains rise — on one side, the Long Kloof Mountains, and on 

 the north the Kammanassie. The village of Uniondale lies in the 

 low level along the Kammanassie Eiver, on a place where a tributary 

 from the Long Kloof has by some curious chance been added to its 

 catchment area, and the impact of this new increment of water has 

 washed out a comparatively wide opening in the river valley. East 



tarn m a.n a^te M>cu*i£u*^ '^£/W 7&y 7%/oe fictrm/ Jajen T&cev- 



FlG. 1. 



P. The High-Level Plateau. R.E. Bed Enon. W. E. White Enon Conglomerate- 

 BV. Bokkeveld Beds. T.M.S. Table Mountain Sandstone. 



The Oliphantfs River Valley, showing the fold-basin of Enon Conglomerate and 



the High-Level Plateau or Bevel. 



of Uniondale there is the Uitvlugt Berg, which seems a considerable 

 mountain from the village, but on getting out of the gorge of the 

 Kammanassie Eiver on to the plain it loses a good two-thirds of it& 

 height ; a shelf belonging to the bevel, and covered with fine, gravel, 

 skirts the mountain on the south side, while on the north side there 

 is the high plateau itself, only indented by shallow river courses. 



At the eastern end of Uitvlugt the river ends blindly in the 

 plateau, and a bunch of finger-like gorges are cut into it. The gravel 

 cap here is very well exposed and is continuous ; in the centre of the 

 double bevel it consists of yellow sand some thirty feet thick. The 

 upper portion of the sand becomes intensely hard, due to the 

 deposition of secondary silica between the sand grains ; lower down 

 the rock becomes softer, and near the bottom is loose, clayey sand 

 that can be dug with a spade. The quartzite-like surface cracks up 



