348 ON THE FORMATION OF CORAL ISLANDS. 



that the calcareous strata have been elevated by the 

 volcanoes of those islands ; which have also, in some 

 parts, broken through them, while, in others, the 

 volcanic matter is still covered and concealed by the 

 limestone, which thus forms the surface of that hill, of 

 which the interior is an igneous rock. It is an unex- 

 pected confirmation of these general views, and inde- 

 pendent of all geology or theory, to find the same 

 belief among the people of Banda ; who, according to 

 Reinwardt, assert that their island is still, visibly, 

 rising. 



There remains a chemical question respecting the 

 generation of coral islands, which is extremely obscure, 

 while it bears equally on the formation of the ordinary 

 stratified limestones. This is the production of the 

 Lime : but chemistry has, hitherto, not a rational 

 suggestion to offer. The fact of which we are sure, 

 is, that the carbonat of lime is formed by animals, in 

 whatever manner. And if the great masses of coral 

 rock thus described be estimated, it will be seen that 

 they are equivalent to some of the largest deposits of 

 secondary limestone existing. That the secondary 

 limestones have been produced by the animals whose 

 shells are still imbedded in them, is far therefore from 

 being so unreasonable an opinion as it has sometimes 

 been considered. It is not compulsory to believe that 

 all limestones have originated in the same sources ; 

 but when we recollect that these rocks abound among 

 the secondary strata, while they are comparatively 

 rare among the primary, diminishing in quantity in 

 proportion as we recede from those periods in which 

 the earth was most fully inhabited, we contemplate a 

 fact which confirms the deduction that may be drawn 

 from the appearances now described. 



