THE 



AMERICAN JOURNAL OF SCIENCE 



[FOURTH SERIES.] 



Art. XIX. — Plains in Cape Colony ; by Professor E. H. L. 

 Schwarz, Rhodes University College, Grahamstown, Cape 

 Colony. 



The southern coastal belt of Cape Colony is divided into 

 two portions, the western with its lofty and rugged mountain 

 ranges, the eastern with more gentle topography. Standing 

 on one of the lofty peaks near the junction of the two zones 

 an almost bird's-eye view can be obtained of the lower country 

 to the east : one sees the land stepped or parcelled out into 

 narrow shelves with abrupt margins facing the sea. The 

 highest of these lies at this point about 2,500 feet and the 

 width of the terraced portions is 30 miles. Travelling through 

 this country, say from Port Elizabeth to Bellevue, the highest 

 point on the railway near here, the terraces are scarcely appar- 

 ent, as the great fall of the rivers has caused deep gullies to 

 be cut, and the subsequent denudation has widened them 

 sufficiently to obscure the details, while the Addo bush, a scrub 

 forest, covers the more characteristic features ; besides this, in 

 the Port Elizabeth area, a belt of soft Cretaceous deposits has 

 been faulted down against the older rocks, and this has allowed 

 wide alluvial plains to be developed. 



Farther east in Pondoland the shelves are far more distinct. 

 The rock is of uniform hardness throughout, and, supporting 

 a rich covering of grass, it has been cleared to a large extent 

 by repeated burning of all obscuring bush and forest. 



In the west the shelves are not very . apparent except the 

 extensive 700-foot one all along the coast, but in favorable 

 spots, especially at the head streams of the great rivers where 

 erosion has had little opportunity of acting, the terraces can 

 be picked out, and the level certainly carried up to 4,000 feet, 

 perhaps higher, to the full maximum elevation of the continent, 

 namely, 6,000 feet. 



Am. Jour. Sci. — Fourth Series, Vol. XXIV, No. 141. — September, 1907. 

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