Geological Aspects of South African Scenery. 357 
The whole of the central plateau, where the Karroo sandstones and 
shales form the surface, shows numerous ridges, scarcely to be called 
hills, which mark the site of basic igneous intrusions, which can often 
be traced for miles across the country. The west and south-west of 
the Orange River Colony often presents what may, on a small scale, 
be termed quite a rugged landscape, owing to the abundant presence 
of dykes and small irregular bosses of dolerite and allied rocks, which, 
even when forming no great elevation above the general level, stand 
out conspicuously from the grassy veld by reason of their dark colour 
and their growth of sparse bush. 
The central 'lransvaal has been largely stripped of its covering of 
Karroo rocks, and the old rocks appear as mountain ridges, which are 
im every case a reappearance of a part of one of the older land 
surfaces. In this portion of the country, whether the rocks belong to 
the Witwatersrand System or the Potchefstroom System, the resulting 
scenery is practically identical—low, but abrupt, escarpments of 
quartzites, with dip slopes inclining north or south, and forming one 
side of a valley which has been carved out of the softer slates or 
shales. The Gatsrand, the Witwatersrand, the Witwatersberg, and 
the Magaliesberg are all instances of this type of scenery—east and 
west ridges with their escarpments facing north or south according as 
the beds dip south or north respectively. Each intervening valley 
has on one side a gentle declivity and on the other a steep pre- 
cipitous wall. 
In contrast to the long lines of sedimentary escarpments, which 
make many of the hills in the southern Transvaal, are the irregular 
masses of Ventersdorp amygdaloid, forming the Klipriversberg and 
the hills south-east of Heidelberg, while north of the Witwatersrand 
there is the undulating landscape due to the presence at the surface of 
a large extent of the old granite. 
Beyond the Magaliesberg, where the great Bushveld massif of 
igneous rocks appears at the surface, the landscape opens out again 
into the broadly undulating type. The more basic of the rocks often 
form hills, such as the Pyramids or Zwartkopjes north of Pretoria, 
but the granitic rocks give a scenery differing in no wise from that of 
the old granite, or, in fact, of any non-mountainous granite area, 
These rocks form a large part of the Bushveld proper, which in many 
places, with its grassy surface and irregularly dotted trees, has a close 
resemblance to the scenery of an English park. 
Where the Waterberg formation appears resting unconformably on 
the Bushveld igneous rocks, or on the old granite of the north, there 
is a return to the escarpment and dip valley type of landscape, which 
is well seen in the hills north of the Premier Mine, the Waterberg 
itself, and the Zoutpansberg still further north. In all these hills the 
reddish-brown colour of most of the Waterberg conglomerates and 
quartzites is always a conspicuous feature. 
By far the larger portion of the northern Transvaal is a granite 
landscape, presenting over thousands of square miles a_ gently 
undulating surface, with occasional bare tors rising like inverted 
bowls above the surrounding country. It is, except in rare seasons, 
a dry country covered by straggling thorn trees, above which rise the 
grotesque limbs of the fantastic baobab. 
