298 DENUDATION OF THE LAND. Chap. VI. 



would in the course of time be filled up and 

 disappear. Some careful observers, however, 

 who examined fields for me in Gloucestershire 

 and Staffordshire, could not detect any dif- 

 ference in the state of the furrows in the 

 upper and lower parts of sloping fields, sup- 

 posed to have been long in pasture ; and they 

 came to the conclusion that the crowns and 

 furrows would last for an almost endless 

 number of centuries. On the other hand the 

 process of obliteration seems to have com- 

 menced in some places. Thus in a grass 

 field in North Wales, known to have been 

 ploughed about 65 years ago, which sloped at 

 an angle of 15° to the north-east, the depth 

 of the furrows (only 7 feet apart) was care- 

 fully measured, and was found to be about 

 4^ inches in the upper part of the slope, and 

 only 1 inch near the base, where they could 

 be traced with difficulty. On another field 

 sloping at about the same angle to the south- 

 west, the furrows were scarcely perceptible 

 in the lower part ; although these same 

 furrows when followed on to some adjoining 

 level ground were from 2\ to 3^ inches in 

 depth. A third and closely similar case was 



