Chap. III. UNDERMINED BY WORMS. 149 



period have rolled down from a rocky moun- 

 tain or cliff on to a meadow at its base, are 

 always somewhat embedded in the soil ; and, 

 when removed, leave an exact impression of 

 their lower surfaces in the under-lying fine 

 mould. If, however, a boulder is of such 

 huge dimensions, that the earth beneath is 

 kept dry, such earth will not be inhabited 

 by worms, and the boulder will not sink 

 into the ground. 



A lime-kiln formerly stood in a grass-field 

 near Leith Hill Place in Surrey, and was 

 pulled down 35 years before my visit ; 

 all the loose rubbish had been carted away, 

 excepting three large stones of quartzose 

 sandstone, which it was thought might here- 

 after be of some use. An old workman re- 

 membered that they had been left on a bare 

 surface of broken bricks and mortar, close to 

 the foundations of the kiln ; but the whole 

 surrounding surface is now covered with turf 

 and mould. The two largest of these stones 

 had never since been moved ; nor could this 

 easily have been done, as, when I had them 

 removed, it was the work of two men with 

 levers. One of these stones, and not the 



