Page:Quarterly Journal of the Geological Society of London, vol. 27.djvu/457

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cannot attempt to give any accurate estimate of the height of the cliffs ; but the two lower stages appeared to me together not less than 500 feet. The strata lay tolerably horizontal, only curving upwards somewhat in the western part of the western cirque. The

Fig. 1. — Rough sketch of Cirque in Rothstock.

A. Clouds concealing peaks. B. Limestone cliffs. C. Shaly slope, with small combes and snow-beds. D. Shaly cliffs furrowed by streamlets. E. Limestone cliffs, occasionally slightly grooved by streamlets. F. Floor of cirque with talus-heaps at side.

most remarkable thing about the cliffs was the belt of reddish shaly rock, which was furrowed by a vast number of little gorges, which were often only a few yards apart and occasionally united, so that this part of the cliff really looked like a badly ploughed field set up on end. Down these gorges, many of them dry in August, little rills descend from the snows on the ledges and in the combes above, which have generally made some trace corresponding with their size on the harder limestone below — sometimes a mere stain, sometimes a well-marked groove.

What explanation, then, are we to give of these rocky recesses with their steep, almost vertical sides, and floors often comparatively level ?

To avoid misconception, let me premise that in adopting any one explanation, I do not mean to absolutely exclude all others, but merely select the one which above all others accounts for the existing physical features. Thus, for example, were I to attribute a valley to the erosive action of a glacier, I should not intend to exclude upheaving forces, denudation by waves, currents, and rivers, &c, all of which may have had much influence in preparing the surface for the glacier, but only mean that the glacier has effaced all, or almost all, the tool-marks of these preceding agencies — just as, when speaking of a statue as carved by a chisel, we take no note of the crowbars, wedges, picks, blast-powder, and other appliances which were employed to quarry the block before it was placed in the sculptor's hands.