Origin of the Cheddar Cliffs. 



35 



exception of man) to carry the detritus away. In most places 

 the rocks have preserved their original smoothness and regu- 

 larity of outline. Here and there concave undercuts run hori- 



N.VK 



S.E. 



Section of Cheddar Eavine. — A, rocks removed ; BB, remaining rocks ; cc, 

 terraces ; dd, undercuts ; e, road. 



zontally along the the faces of cliffs, while at the base of others 

 there are cavernous recesses with water-worn roofs. But the 

 most instructive forms of rock surface are the planes caused by 

 jointing and bedding. They show that the mode in which the 

 adjacent blocks or masses were carried away was not a process 

 of granular dissolution, nor even fragmentary dilapidation, but 

 a bodily displacement. The cause must have been equivalent 

 to the translation of large blocks of limestone. To borrow 

 an illustration from the well-known cheese of the neighbouring 

 plain of Cheddar, if a farmer were to find one morning that a 

 part of a cheese was missiug, and that the surface left was 

 smooth and regular, he would conclude that some person had 

 cut a slice with a knife, not that a mouse had been nibbling 

 at the cheese during the night ; or, suppose the farmer were 

 to find that a whole cheese had been removed from his store- 

 room, he would at once conclude that a power capable of 

 carrying it away in a lump had been concerned in the theft. 

 A puny agency, which carries on its work grain by grain, or 

 bit by bit, cannot leave a smooth, plain, and regular surface 

 of any extent ; but a violent and powerful agency, while it is 

 not incapable of leaving a rough surface (circumstances being 

 favourable), mainly tends to produce breadth and uniformity of 

 contour. 



The most philosophical way of trying to explain natural 

 phenomena is to seek for similar phenomena now in course of 

 being produced; and many modern sea-coasts exhibit fac-similes 

 of the Cheddar cliffs. The forms of these cliffs are precisely 

 those which would result from waves driven by storms into a 

 narrow inlet of the sea. At a greater elevation, near the summit 

 of the Mendip hills, smoothed (sometimes polished), rounded, 

 hollowed, perforated, and grooved surfaces of rocks may here 

 and there be traced. The way in which they have been shaped 



