TRANSITION LIMESTONE. 9 



unrecorded concussions since the great subversion, 

 of our planet have, in remote periods, effected many 

 of the removals of these deposits. We find the 

 basement of many of the South Sea Islands, some 

 of which are twenty miles long, formed of this 

 matter. Captain Flinders, in the gulf of Carpen- 

 taria, held his course by the sides of limestone reefs, 

 five hundred miles in extent, with a depth irregular 

 and uncertain ; and still more recently Captain, 

 King, seven hundred miles, almost a continent, of 

 rock, increasing, and visibly forming : all drawn 

 from the waters of the ocean by a minute creature, 

 that wonderful agent in the hands of Providence, 

 the coral insect. This brief account of the origin 

 of calcareous rocks was, perhaps, necessary before 

 mentioning an extraordinary fact, that, after the 

 lapse of so vast a portion of time since the base- 

 ment of the mighty deep was heaved on high, 

 existing proofs of this event should remain in our 

 obscure village. 



The limestone rocks here are differently com- 

 posed, but are principally of four kinds a pale 

 gray, hard and compact ; a pale cream-coloured, 

 fine-grained and sonorous ; these form the upper 

 stratum of stone on our down, a recent deposit, or 

 more probably a mass heaved up from its original 

 station. The whole of this mass, running nearly 

 half a mile long, is obviously of animal formation, 

 a coral rock ; a compounded body of minute cylin- 

 drical columns, the cells of the animals which con- 

 structed the material, the mouths of which are all 



