SOIL OR SURFACE-MATTER. 229 



may not have been very apparent. Nevertheless, 

 he seems to prove that, in one instance, the vegetable 

 decay, not the earthworms, buried the foreign sub- 

 stances, namely, that of the boggy field which was 

 covered over with a coat of gravel, and in two years 

 and a half afterwards there was a peaty layer three- 

 fourths of an inch thick grown over it. Very similar 

 instances occur, and may be examined in many places 

 in Ireland among the reclaimed cutaway bogs, or as 

 they are locally called, Moors. These moors are 

 generally tilled for a few years previous to being 

 laid down in grass, after which a coat of marl or 

 gravel is spread on them. If they are to be kept 

 in good heart, more gravel or marl must be applied 

 to them from time to time, and the drainage 

 attended to ; but if they are neglected, as is too 

 often the case, they will tend to return to their 

 former state, and in a short time a layer of peaty 

 soil will grow on the marl or gravel. It is not 

 uncommon in these moors, if a section is opened 

 through them, to see one, two, or even three of 

 these layers of foreign matter, pointing out the 

 number of times the moor was " brought in," and 

 afterwards allowed to run wild. 



Any one acquainted with bogs well knows that 

 earthworms cannot live in them ; a few may be found 

 in reclaimed moors in the made soil, both while they 

 are in tillage and under grass ; but once the original 



