Page:South African Geology - Schwarz - 1912.djvu/150

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SOUTH AFRICAN GEOLOGY

it forms the abrupt ranges of Hottentots' Holland and the Drakenstein or Stellenbosch Mountains; then northwards it is found in the Great Winterhoek and Cedar-Mountains, and eastwards in the Langebergen, Outeniquas, and Cockscomb Mountains. The Zwartberg Range is an independent parallel range to the last. The series is cut into the coastal shelf in Humansdorp and Port Elizabeth and then disappears beneath the sea at Cape St. Francis. It comes in again as an isolated mountain surrounded by glacial moraines (Dwyka Conglomerate) at the mouth of St. John's River, the gates of which it forms. Then from Waterfall Bluff, where the streams pour their waters over a cliff into the sea, the Table Mountain Sandstone forms the coastal plateau through Pondoland to Natal, and becomes lost again beneath the glacial moraines somewhere near Durban.

The vegetation of the Table Mountain Sandstone is at once the pride and despair of South Africans. It supports the extraordinary proteas or sugar bushes, the disas, watsonias, gladiolas, heaths, and everlasting flowers of the Cape, which are the most beautiful of all wild flowers, and also the great forests of Knysna, with the majestic yellow-woods, rising 80 to 100 ft. in superb columns, and then branching out into gigantic panoplies of foliage. In the Cedar Mountains there are the Cape Cedars, which grow nowhere else in the world. The soil on the Table Mountain Sandstone is sour, and the grasses can only be eaten when quite young by cattle, and hence the old grass is periodically burnt off. This burning has destroyed first the forests, and is now doing away with the soil itself, for the soil, unprotected by vegetation, becomes washed away by the rains, and nothing but bare rock is left. The Cape Mountains, therefore, denuded of