E. H. L. Schwarz — Gold in Cape Colony. 



371 



thrust sheared the termination and deflected the great arm of granite 

 seawards. 



Where the granite ends the whole nature of the rocks of the 

 mountains changes ; no longer have we miles of strata on end, as 

 near George, but the folds widen out, and dips of 10° to 15° prevail. 

 West of this point the dips are south all through the mountain 

 ranges ; east of this point there are both north and south dips ; in 

 other words, the folds are upright and open, instead of being pressed 

 together, and inclined to the south. 



The direction of the granite dykes is near here N.E., and then 

 suddenly swings round to E.N.E., so in the strike of the Table 

 Mountain Sandstone there is a sudden change from east and west to 

 E.S.E. Any small scale map of South Africa will show distinctly 



50KKE.V ELD 



Fig, 1. — Map of the Coastal Plateau in George and Knysna, showing the bending 

 of the strike round the end of the granite. 



the streaming of the mountains round a point near George, and the 

 recent survey of that part by the author showed that the cause of 

 this change in the direction of the mountain chains was the termi- 

 nation of the granite. It is not till we get beyond the colony 

 borders into Natal that we find granite again along the southern part. 

 It is in the angle of the bend in the Table Mountain Sandstone 

 that the fissures occur which are now filled in with auriferous 

 quartz. In between Millwood and the granite there is a syncline 

 filled in with Bokkeveld Slates, and the quartz-reefs traverse the slate 

 formation equally with the sandstone formation ; but there are 

 certain differences. In the slate the quartz-reefs are massive bodies 

 of white veinstone, with a certain amount of pyrites and copper 

 pyrites included in it ; none of the reefs have yet been opened up 

 properly, but they appear to be continuous over large areas and are 

 constant with depth. They do not branch or break away from their 

 general lie, which is parallel to the strike of the rocks, but with 

 a dip somewhat greater. In the sandstone the veins are much less 



