288 DENUDATION OF THE LAND. Chap. VI 



above the mouths and on the windward side 

 as 2 J to 1 ; whereas we have seen that with 

 several castings which had flowed down slopes 

 having a mean inclination of 9° 26', and with 

 three castings where the inclination was 

 above 12°, the proportional weight of the 

 earth below to that above the burrows was 

 as only 2 to 1. These several cases show how 

 efficiently gales of wind accompanied by rain 

 act in displacing recently-ejected castings. 

 We may therefore conclude that even a 

 moderately strong wind will produce some 

 slight effect on them. 



Dry and indurated castings, after their dis- 

 integration into small fragments or pellets, are 

 sometimes, probably often, blown by a strong 

 wind to leeward. This was observed on four 

 occasions, but I did not sufficiently attend to 

 this point. One old casting on a gently slop- 

 ing bank was blown quite away by a strong 

 south-west wind. Dr. King believes that 

 the wind removes the greater part of the 

 old crumbling castings near Nice. Several 

 old castings on my lawn were marked with 

 pins and protected from any disturbance. 

 They were examined after an interval of 10 



