338 



EAETH-PILLARS 



[Ch. XV. 



Thirdly, the chasm / b was cut out of this moraine by the 

 Finsterbach, the red mud presenting a perpendicular face 

 towards the chasm. This mud, which is very hard and solid 

 when dry, becomes traversed by vertical cracks after havin 



S 





been moistened by rain and then dried by the sun. Those 

 portions of the surface which are protected from the direct 

 downward action of rain by a stone or erratic block, become 

 gradually detached and isolated near the edge of the ravine, 



columns 



If the 



small 



minates 



large, sometimes 



diameter, the column may 



more and more 



upper portion where its sides have been longest exposed to 

 the beating of the rain, it still continues to support the over- 

 hanging mass, which often looks as if poised on a point. 



Many 



fallen blocks, once the cappings of pillars 



which have disappeared, are now seen in the bed of the 

 torrent, and their former position and the pillars on which 

 they rested are expressed by the faint outlines given in the 

 figure. The lower parts of some of these ancient columns 

 still exist, because they have acquired new capping-stones by 

 the weathering out at the surface of blocks originally buried 



Had 



at great depths in the moraine, 

 during the long period required for the formation of the 

 pillars, even a few yards above its present height, it would 

 have swept away the lower columns, which are due therefore 

 to pluvial action, not interfered with by fluviatile erosion 



If we ascend above a or c 



to heights commanding a 



general view of the valley and moraine, the lateral terraces 

 d g and h e look almost flat when contrasted with the pre- 

 cipitous cliffs g i and h i, for the latter slope at angles varying, 

 as above stated, from 32° to 45°, whereas the terraces afford- 

 ing rich pastures and arable lands slope at angles varying 

 from 10° to 16°. Here and there a large boulder or an angular 

 erratic block is seen lying on the surface, as between h and e, 

 which at some future time will probably become the head of 

 a column. I measured one of the capping-stones on the left 

 bank of the Finsterbach not far below the bridge, and found 







