80 THE UNIVERSE. 



the Cordilleras, astonish us by their mass and their eleva- 

 tion. But there are others which, though less gigantic, 

 have quite as marvellous an origin, although of a different 

 kind ; these are the mountains of shells. 



The exuberance of life in the ancient oceans surpassed 

 everything that we can imagine ; our modern seas give us 

 no idea of it. The molluscs lived at that time in such ser- 

 ried and compact masses that their remains have produced 

 by their accumulation deep strata and lofty eminences. 



The phenomena which prevailed when these were gen- 

 erated exhibit a threefold modification. 



Sometimes seas, the calmness of which rivalled their 

 fecundity, had their beds slowly raised, the cemeteries of 

 their innumerable inhabitants being in this way raised also. 

 The shells, quietly deposited there one upon another, show 

 no trace of erosion. After so many thousands of years we 

 find them still ornamented with their most delicate projec- 

 tions, with their almost imperceptible striae. What do I 

 say ? There are some which still reflect the colors that 

 decorated them in the first days of creation, long before 

 the work was finished ! 



In other places, swarming in the midst of a boundless 

 ocean tumultuously agitated, the shells, ground by its furi- 

 ous waves, and precipitated in the form of impalpable dust, 

 also formed mountains. 1 



However extraordinary such an origin may seem, we yet 

 cannot doubt it ; in fact, in certain localities we pass by in- 



1 To these crushed shells, which compose the principal part of the grains of 

 calcareous strata, are joined also, as Lyell points out, the shattered remains of a 

 vast number of polyp-dwellings. 



