xx Transactions of the South African Philosophical Society. 



mountains, and the time consumed in reducing the level of these 

 poorts was sufficient to allow the rivers to cut extensive plains 

 behind them. The plains may be divided into four sets : No. 1, 

 the Agulhas Plain, whose edge is known as the Agulhas Bank, was 

 almost certainly dry land at one time, but it is now covered with 

 40 fathoms of water. No. 2, the Kuggens and flat-topped hills and 

 coastal plains all along from Cape Point to the Natal border. This 

 is often divided into several stages, each forming a vast step. After 

 the initial rise, the rivers once more cut vigorously downwards, and 

 have cut deep gorges, 500 to 800 feet deep, in this old land surface. 

 No. 3, a series of plains in between the parallel coastal ranges. 

 Owing to the narrowness of the space these are seldom true, 

 level plains, but can be better described as bevels or inclined plains. 

 No. 4, a plateau of about 3,500 feet above the sea-level, of which 

 only a few remnants can be seen here and there. Nos. 3 and 4 are 

 probably in places confluent, and possibly also formed in remote 

 times one vast shelving tract of open plain from the Nieuweveld and 

 Camdeboo Mountains to the sea by Port Elizabeth. Near the 

 mountains these old land surfaces are covered with gravel, but 

 further away there is more sand, yet all varieties of river-borne 

 material occur. The sand when exposed on the hill-tops has been 

 mistaken, from its peculiar position and appearance, for lava flows, 

 diamond breccia, and gold quartz ; the sand, cemented either by 

 infiltration of iron or of silica, becomes either an ironstone' or a 

 quartzite. Excellent building stones occur among these deposits. 

 The Prince iUbert Gold Fields were opened in 1891, amid great 

 excitement, 1,042 claims being registered in the first four months 

 and 504 ounces of alluvial gold found. The fields attracted a great 

 deal of attention, and a large amount of prospecting was Gamed on 

 in the neighbourhood, but no reefs have up to the present been dis- 

 covered. In the Zwartebergen, however, there is always a little gold 

 to be found in the sandstone, especially in the neighbourhood of 

 gravel or banket reefs, as in the Millwood gold area in Knysna. 

 Such banket reefs, of which photographs and specimens were 

 exhibited, occur in the Zwartebergen. It is now certain that the 

 hills at the Prince Albert Gold Fields once formed part of the great 

 plateau of which traces can be found on the sides of the Zwarte- 

 bergen and on the outer range of hills made of Witteberg beds, and 

 as this was formed by the cutting of rivers flowing northwards from 

 the mountains, it is highly probable that the Prince Albert gold came 

 from the Zwartebergen, and not from its disintegration of reefs in 

 the neighbourhood, the latter being in rocks of comparatively recent 

 age, and, therefore, hardly to be expected to' be metalliferous. 



