724 ME. E. H. EASTALL ON THE GEOLOGY OF [NOV. I9H, 



which are here reddish shales with occasional bluish grit-bands, 

 intensely folded and contorted. This folding is of a very peculiar 

 character, since many of the folds are in the horizontal position, 

 with their axial planes vertical. It is evidently impossible 

 to represent this in a diagram. Sometimes, for considerable 

 distances the strike of the beds is nearly north-east and south- 

 west, that is, at right angles to the normal strike of the district ; 

 but the general trend appears to be north-west and south-east. 

 In the arches of the anticlines are occasional patches of crush- 

 breccia. The total width of the outcrop of the Witteberg Beds in 

 the river is about 1000 yards. 



The exact position of the great fault between the Witteberg and 

 the Malmesbury Beds is very clearly indicated, and the strikes of 

 the two series are quite different. The structure of the Malmes- 

 bury Series is much simpler, and the dips more uniform ; the folds 

 which can occasionally be seen are not of much importance. The 

 rocks of this series are for the most part silvery or blue slates, 

 weathering yellow, with occasional grit-bands. The width of the 

 outcrop of Malmesbury Beds is here about 800 yards, and at one 

 point a fault is very clearly seen in the middle of the series. 



The junction with the Table Mountain Sandstone is almost 

 vertical, and the lowest bed of the latter, about 4 feet thick, 

 appears to be a basal conglomerate of quartz-pebbles, which has 

 been afterwards infilled with vein-quartz. It presents a strong 

 superficial resemblance to the bankets of the Rand, and has been 

 unsuccessfully prospected for gold. The Table Mountain Sandstone 

 itself is here of the usual character, and calls for no comment. 



This section is of especial interest, since it displays very clearly 

 and in a compact form a typical series of the rocks of this district. 

 Incidentally it may be mentioned that the published map of the 

 Geological Commission of the Cape of Good Hope, on the scale of 

 3| miles to the inch, is incorrect at this point, since it shows the 

 river flowing over Malmesbury Slates and Enon Conglomerate only, 

 whereas the Witteberg Slates are seen in the banks of the stream 

 for nearly 1000 yards. It appears, therefore, that there is actually 

 a narrow tongue of Witteberg Beds running between the outcrop 

 of the conglomerate and the fault, across the stream ; and the Enon 

 Conglomerate is here not cut off by the fault, although it comes 

 against it a little farther north. 



The fine exposure of Enon Conglomerate on the right bank of 

 the river forms a prominent cliff about 40 feet high, of which the 

 uppermost 10 feet or so is recent alluvium, consisting of yellow 

 gravel with very big boulders of Table Mountain Sandstone up to a 

 cubic yard in bulk. About 30 feet of the conglomerate is exposed, 

 consisting of boulders measuring as much as 1 cubic foot, embedded 

 in a reddish sandy matrix. Bedding is distinctly shown, and the 

 dip is about 10° southwards. The boulders in this conglomerate 

 consist exclusively of sandstones and grit, mostly resembling those 

 of the Witteberg and Ecca Series ; and, despite the most diligent 

 search, no fragments of Malmesbury rocks could be found. 



