1871.] 



BO?!-NEY FORMATION OF " CTRQTTES." 



315 



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 cliifs. C Shaly slope, with 

 small combes and snow-beds. D. Shaly clifis furrowed by streamlets. 



E. Limestone cliifs, 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 exist- 

 ing physical features. Thus, for example, were I to attribute a valley 

 to the erosive action of a glacier, I should not intend to exclude up- 

 heaving 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 

 aU, the tool-marks of these preceding agencies — just as, when speak- 

 ing of a statue as carved by a chisel, we take no note of the crow- 

 bars, wedges, picks, blast-powder, and other appliances which were 

 employed to quarry the block before it was placed in the sculptor's 

 hands. 



