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rock, such as the Inferior Oolite, the Coralline Oolite, and the 

 Portland series ; that the Coralline theory applied only to the 

 oolitic limestones, for the argillaceous deposits have clearly been 

 formed under other conditions. Nearly all the oolitic limestones 

 contain coral structures more or less extensive ; in the Inferior 

 Oolite were three distinct reefs super-imposed on each other, 

 having intermediate beds of ooKtic rock ; the Great Oolite had 

 its reef, the Coral Eag possessed its reef, and the Portland beds 

 contained zoophytie productions in like manner. Now there 

 was no doubt in the mind of any one who saw such a rock as 

 he (the lecturer) held in his hand, but that it was a mass of coral 

 secreted by a Jurassic Zoophyte. But what was the roe-stone or 

 Oolitic rock which rested upon the reef ? He submitted that it 

 was neither more nor less than a portion of the wasted reef 

 which had been broken and triturated and ground into mud ; 

 that the paste had coated particles of sand, and the whole had 

 been cemented by the calcareous waters, and formed into the 

 rock we call Oolitic Limestone. For all these granules had a 

 nucleus, and the calcareous globule was made up of a succession 

 of laminae, as may readily be seen in thin sections of the rock 

 prepared for the microscope. So the genesis of the oolitic rocks 

 was due to the vital energies of the zoophytes that lived in the 

 Jurassic seas. The reefs that remained were mere fragments of 

 those which had once existed, and the reefs that had disappeared 

 had furnished the materials out of which the oolites had been 

 constructed. The same explanation would apply to the OoKtic 

 beds found in the Carboniferous Limestone, which had been 

 formed by the waste of the Coral beds in the Carboniferous seas. 

 But the oolitic grains of the Carboniferous oolites had often a 

 small foraminiferous shell as a nucleus, instead of the particles 

 found in the Jurassic oolites ; but in both cases the process of 

 production was the same ; the granules had been rolled along a 

 shore and cemented into a i*ock by a calcareous cement, just as 

 Oolitic beds are now in course of formation along the shores of 

 the coral reefs of oiir own day. There was only one true 

 method to interpret Nature, and that was to watch how she 

 proceeded in any of her operations, and thus, having learned 



