282 DENUDATION TO LAND CHAP. VI 



on the Alps of Switzerland, and states that 

 they ran at 3 or 4 ft. one above the other, 

 and were about a foot in breadth. They had 

 been deeply pitted by the feet of grazing cows. 

 Similar ledges were observed by the same 

 friend on our Chalk downs, and on an old 

 talus of chalk-fragments (thrown out of a 

 quarry) which had become clothed with turf. 

 My son Francis examined a Chalk escarp- 

 ment near Lewes ; and here on a part which 

 was very steep, sloping at 40 with the 

 horizon, about 30 flat ledges extended hori- 

 zontally for more than 100 yards, at an average 

 distance of about 20 inches, one beneath the 

 other. They were from 9 to 10 inches in 

 breadth. When viewed from a distance they 

 presented a striking appearance, owing to their 

 parallelism ; but when examined closely, they 

 were seen to be somewhat sinuous, and one 

 often ran into another, giving the appearance 

 of the lodge having forked into two. They 

 are formed of light-coloured earth, which on 

 the outside, where thickest, was in one case 

 9 inches, and in another case between 6 and 

 7 inches in thickness. Above the ledges, the 

 thickness of the earth over the chalk was in 



