'264 THE NIEUWEVELD SHEETS 



miles along the edge of the escarpment, the highest 

 point of which is the peak called Bulthouder's Bank, 

 6,270 feet above sea level and 3,500 feet above the 

 town of Beaufort West, which lies about seven miles to 

 the south-east. 1 



The Eooi Hoogte sheet, which is inclined northwards 

 at a moderate angle, fronts the Great Karroo for nearly 

 fifty miles and forms the southernmost of the dolerites 

 for a distance of over seventy miles. It may have ex- 

 tended some way farther south than its present out- 

 crops, but as there are no other dykes to the south, i.e., 

 no channel whence further sheets could have been sup- 

 plied, and as there are no outliers of dolerite in that 

 direction, we must regard the present outcrop of the 

 Rooi Hoogte sheet as near the former southern limit of 

 the intrusions. 



The exact position of the southern edge of the 

 dolerite country is not known east of Beaufort West, 

 but the boundary runs between Aberdeen and Graaff 

 Reinet, and follows, roughly speaking, the line of railway 

 from Cookhouse to East London. Beyond East Lon- 

 don the dolerites appear in great force throughout the 

 whole of the Transkei and they are continued right 

 through Natal. 



North-west of the Nieuweveld there are numerous 

 dolerite- capped hills, e.g., the Karree Bergen, Slang 

 Bergen, Tulbagh Mountains, Kat Kop hills, and the hills 

 south of Williston (Amandelboom). 



1 A detailed description and map of the sheets and dykes of the 

 eastern Nieuweveld will be found in G. C., i., pp. 15-26 ; of the Roggeveld 

 jn O. C., v., pp. 50-52, and viii., pp. 36-43- 



