Vol. 62.] 



IN THE SOUTH-WEST OF CAPE COLONY. 



81 



with the question of the permanence of the continental outlines 

 in past ages : that is a question which may be decided one way or 

 another, without affecting the absolute base-level. I have intro- 

 duced the expression because I wish to imply that continents are 

 in a state of motion, upwards or downwards, and that the absolute 

 base-level represents the ocean-floor, including the shelf or level of 

 erosion cut by the surf and off-shore currents that came near the 

 water's edge when the depression of the present land-masses com- 

 menced ; it is a datum from which to reckon those upward or 

 downward movements of continents which are actually in progress. 



Pig. 3. — The Be Vlugt plateau (about 1500 feet), looking north 

 from Paarcle Kop (2397 feet), across the valley of 'the Keurbooms 

 Hirer. 



)A\AiA\ x\//V/\v 



[In the distance are the Long Kloof Mountains, which may be the remnants 

 of a higher plain, 5000 to 6000 feet above sea-level ; the crests are seen to 

 run in a remarkably-level line, and the highest peak of the range (Krakeel 

 Eiver) has an altitude of 5500 feet. The valleys are occupied by outliers 

 of Bokkeveld Slates folded in with the Table-Mountain Sandstone.] 



In the Division of Knysna there is a complex of ridges under the 

 mountains, formed by folded Table-Mountain Sandstone, with syn- 

 clines filled in with long outliers of Bokkeveld Slates. Although the 

 synclines pitch so that the slates are often cut out, and the sand- 

 stone-strata in places stand vertical, at others with very high dips, 

 yet the tops of the ridges all rise to a level sky-line about 1500 to 

 2000 feet above sea-level. Peaks rise above this ; but the evidence 

 is satisfactory for the existence in past ages of a plateau at an 

 altitude of about 1500 feet. 



Behind the mountains are the remains of a vast plateau, at about 

 Q. J. G. S. 'No. 245. g 



