Page:Quarterly Journal of the Geological Society of London, vol. 27.djvu/707

 been subjected to oceanic agency: we must therefore look for other causes to account for the vast alteration that the surface of the country has undergone.

Some of the facts that I have been able to collect as bearing upon the case are as follows : —

Katberg, and, its Roches moutonnees and Moraines. — Commencing with the Katberg range, we remark that the face of these mountains on the south side, towards the sea, is generally abrupt and precipitous (this is the case with most of the mountains of the Dicynodon formation), while on the north side, as seen along the road, the rocks are all dome-shaped, or rounded and smoothed off, presenting a marked contrast to the opposite side. In the descent of the mountains on the north side, on some of the shoulders and in a number of places at high levels, are found large lateral accumulations of angular fragments of rock, of various sizes, generally imbedded in clay. After following the curvings of the long valley leading to Langfield, we find large transverse mounds of drift and boulders, upwards of 60 or 70 feet high, that have afterwards been cut through where the present watercourses run (see Section X). There are also large deposits of unstratified clays, full of angular boulders of every size, from small gravel and pieces of a few pounds' weight to masses of several tons, turned and tilted into every position. I have not had an opportunity of carefully examining these fragments for striae or groovings. In several instances I have found transverse mounds, rising like small hills, in far wider valleys, and many miles from the high mountain-ridges whence the boulders have apparently come. At the Bolotwa, in the valley in which the Mission -station is situated, are a number of detached " kopjes," formed of large boulders piled together, and imbedded, as far as can be seen, in a matrix of stiff, black, somewhat loamy clay. Here also the boulders are mixed together indiscriminately; in some parts they are very compact, and numbers are of many tons' weight. The largest of these mounds has the side towards the top of the valley quite abrupt, and it there rises to a height of some 70 or 80 feet. Prom the foot of this one a bed of clay and boulders stretches for more than a thousand yards through the Mission-station, where it appears to rest upon a loose gritty sandstone (very similar to that at a place called the Bongolo Neck, which I shall presently mention) in which large boulders are imbedded. Again, some 12 miles nearer Queenstown there is a high broken ridge of boulders, which the present watercourse of the Inquobo (a torrent in rainy weather) cuts through at nearly a right angle. A small section of this is exposed by a road-cutting ; and in two places the boulders are found resting upon stratified rocks (shale), whilst in another they lie on a bed of the same " whirled " sandstone, with its imbedded boulders, as that at the Bongolo Neck (see above) ; in some parts this ridge of boulders is from 900 to 1000 yards wide, and from about 90 to 100 feet high.

About a mile and a half from this, the whole surface of the precipice along the range of mountains on the south side of the road is smoothed and rounded off in a very remarkable manner. This is