Frof. E. H. L. Schwarz — The Waterherg Sandstone. 425 



The Table Mountain Sandstone surrounds tlie sub-continent on the 

 west and south, and is usually marked in on the east as well, but 

 in N^atal Mr. Anderson at first refused to consider the sandstones as 

 equivalent to the Table Mountain Sandstones, calling them instead 

 Palaeozoic Sandstones. The only place I have seen the Katal Sand- 

 stone was near Pinetown, where the rock is a red arkose. 



On the west the Table Mountain Sandstone is typically developed 

 on the mainland opposite the Cape Peninsula, where it is some 

 5,000 feet thick; proceeding northwards the sandstones thin out, 

 and gradually the overlying beds, the Bokkeveld (Devonian) and 

 "Witteberg Beds, disappear from beneath the Dwyka (glacial) Con- 

 glomerate, so that the last rests on the thinned- out Table Mountain 

 Sandstone ; finally at Stinkfontein Poort, north of Van Rhyn's Dorp, 

 the Table Mountain Sandstone itself wedges out. We can to a certain 

 extent examine the rocks below the Karroo by means of volcanic 

 pipes, which act as boreholes, bringing the rocks to the surface, and 

 we know from the ejactamenta of the Sutherland volcanic pipes that 

 the Table Mountain Sandstone must underlie the Karroo in this part 

 of the country, so that in di'awing a section through the middle of 

 South Africa we cannot be far wrong in filling in the sub-structure on 

 the lines indicated in the upturned edges of the basin in the west. 



M. Malmesbury ( ^^^,:^ T.M.S. Table Mountain; B. Bokkeveld ; W. Witteberg ; 

 X. Matsap I r rl ^' ^^)'^^ i ■^* Karroo, with intrusive Dolerite. 



Sketch Section through the middle of South Africa from the south to just beyond 

 the Orange Eiver on the north, to show the relationship between the Dwyka 

 Conglomerate and the Table Mountain Sandstone on the one hand, and the 

 Dwyka Conglomerate and the Matsap (W''aterberg) Sandstone on the other. 



A short way to the north of the Stinkfontein Poort there is a series 

 of remarkable arkoses and grits which Dr. Rogers named the 

 Meuwerust Beds,^ which undoubtedly lie unconformably below the 

 Table Mountain Sandstone, and which, therefore, belong to the Pal- 

 Afric group. Further to the north, in Namaqualand, there has been 

 marked on the older geological maps of South Africa a patch of 

 Table Mountain Sandstone. I can give the authority for this from 

 the original notes made on the spot b}' the late Dr. W. G. Atherstone 

 in 1854: " Schaap River. Granite forms the base of the mountain, 

 gneiss above it, and, covering all, the Table Mountain quartzite. 

 (The latter is) externally of a red colour, and breaks off in vertical 

 cliffs, but (with) apparently horizontal beds precisely like Table 

 Mountain." I think there can be little doubt that this Schaap River 

 Sandstone belongs to the Nieuwerust Beds ; certainly it is different 



1 JSTinth Annual Eept. Geol. Comm. (Cape Town, 1905), p. 35. 



