36 TOWN GEOLOGY. [i. 



rocks, there will be no use in my going on with these 

 papers. 



Suppose then (to argue from the known to the 

 unknown) that you were watching men cleaning out a 

 pond. Atop, perhaps, they would come to a layer of 

 soft mud, and under that to a layer of sand. Would 

 not common sense tell you that the sand was there 

 first, and that the water had laid down the mud on the 

 top of it ? Then, perhaps, they might come to a layer 

 of dead leaves. Would not common sense tell you 

 that the leaves were there before the sand above them ? 

 Then, perhaps, to a layer of mud again. Would not 

 common sense tell you that the mud was there before 

 the leaves ? And so on down to the bottom of the 

 pond, where, lastly, I think common sense would tell 

 you that the bottom of the pond was there already, 

 before all the layers which were laid down on it. Is 

 not that simple common sense ? 



Then apply that reasoning to the soils and rocks in 

 any spot on earth. If you made a deep boring, and 

 found, as you would in many parts of this kingdom, 

 that the boring, after passing through the soil of the 

 field, entered clays or loose sands, you would say the 

 clays were there before the soil. If it then went down 

 into sandstone, you would say would you not ? that 

 sandstone must have been here before the clay ; and 

 however thick even thousands of feet it might be, 

 that would make no difference to your judgment. If 

 next the boring came into quite different rocks ; into 

 a different sort of sandstone and shales, and among 

 them beds of coal, would you not say These coal-beds 

 must have been here before the sandstones? And if 

 you found in those coal-beds dead leaves and stems of 



