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place. The sea bottom began to rise, and, in time, slowly emerged 

 above the waters. This was the first appearance, as dry land, of 

 the Carboniferous Limestone plateau, which presently was to 

 form the Mendip Range. As this upheaval slowly proceeded, the 

 lime debris dried and consolidated, and, partly by pressure and 

 also by chemical changes, became hardened (as long ages passed) 

 into the dense calcareous rock we find comprising the cliffs of 

 Cheddar to-day. 



But some may ask what caused this rising up of the sea 

 bottom, and the appearance of the future Mendip Hills as islands 

 in the waters? We may get an idea of this process from the 

 analogy of an orange, the skin of which has puckered up mto 

 wrinkles as the pulp shrank from loss of moisture. So, ages' ago, 

 the hardened surface of the earth puckered up into ridges, which 

 formed elevated plateaus and sometimes mountain ranges, as 

 the interior diminished in bulk through cooling of its contents. 

 As the future Mendips were so raised up, the sea retreated, and 

 a sea beach formed a fringe around the elevated masses of lime- 

 stone. This beach would consist of sand and shingle, but also 

 largely of fragments of limestone broken oft 0 by waves from the 

 adjacent cliffs. The remains of this beach, now hardened into 

 stone, are formed as a fringe, now lying around the base of the 

 Mendip Hills on the edges of the limestone. It is the next forma- 

 tion in point of time to the Carboniferous period, and is known 

 to geologists as Dolomitic Conglomerate. It can be seen about 

 a mile below Cheddar. 



Having now briefly traced the mode of formation and rising 

 up of the limestone, let us inquire how this magnificent gorge was 

 carved. First, we must state that similar gorges are common 

 in limestone formations. There are several others in the Mendips, 

 Burrington Combe is, perhaps, the best known, and though none 

 approach Cheddar in depth and grandeur, they were all formed 

 upon the same plan and by the same natural forces. Each begins 

 as a depression on the top of the limestone plateau at some distance 

 from the edge, and winds gradually down to the base, where it 

 widens out, but retains nearly the same width to near its termina- 

 tion. The descent is usually too steep to have been caused by 

 a surface stream, also the bends in its course are sharp, some- 

 times at right angles, an effect never produced by surface rivers, 

 which tend to flow in curves. 



The next point to observe is the property massive limestone 

 possesses of splitting into huge blocks, known to geologists as 

 " joints." These roughly rectangular masses are split off by 

 fractures occuring at right angles to each other, and perpendicular 

 to the " lines of stratification," which represent the beds or planes 

 in which the strata was originally deposited horizontally af the sea 

 bottom. These joints can be readily detected in many parts of 

 Cheddar Cliffs, but thev show better in quarries, and best of aU 

 on a frontage of sea-cliffs. Now, these fissures dividing the joints 



