Page:Quarterly Journal of the Geological Society of London, vol. 27.djvu/709

 of several hundred feet, with large mounds of drift, containing angular fragments of rock, intermixed with others more waterworn, impressing one with the idea that they are, in all probability, the remains of lateral moraines.

Fig. 15. — Section showing the denudation of the Schaap-Kraal Hoek. (Section Z of Author.)

Watercourse.

1, 1. Abrupt escarpments of the outer face.

2, 2. Sloping surfaces of the interior.

3. Clay and other alluvium.

Bongolo. — The Bongolo valley, as well as a number of other large valleys around Hangklip, are very similar in regard to the way in which their interiors have been denuded, and also in the precipitous appearance of the outer side of their surrounding mountains. Hangklip, rising 6800 feet above the sea-level, seems to be the culminating height from which these radiate.

Ice-scratches. — The only place where I have distinctly noticed groovings on the surface of these rounded rocks was at a place called Reit-Poort, in the Tarka ; and here most of them were so marked. The remote date of the denudation, and the nature of most of the rocks, may explain why so few instances of ice-scratches have yet been noticed.

Buffel-Doorns Flat. — The lines of drainage of the country do not always appear to have been the same as at present, as during the erosion of all these valleys there seems to have been a difference from what obtains now, not only in the level of the interior of these basins themselves, but also in their several outlets ; this is seen along the sides of the valley (Buffel-Doorns Flat) represented in section, fig. 16. Here we have three such openings, at three different levels. On the outer side of these outlets there are deep gorges cut through the mountains, leading generally to other wide basins at a lower level ; while these, again, are connected, in the same way, with others of a less elevation than those immediately above. The sides of these gorges are frequently covered with heaps of huge boulders of every shape and position, drift, and accumulations of unstratified clay. This succession of outlets is particularly well marked in this basin, on the southern slope of the Stormberg, called Buffel-Doorns Flat. A number of other basins, similar to this, situated among the branches of the same range, have their present drainage through that of Buffel-Doorns. Almost invariably all the inner faces of these basins are smoothed off, as has