GENERAL REMARKS ON 



This alone, I may venture to suggest. I have not 

 here noticed the lignite-coal deposits in these strata, 

 because they belonged to a subsequent chapter ; but. 

 doubting if those in the oolithe could have possessed 

 their present characters without some essential changes 

 in the positions of the surrounding strata, analagous 

 to those in the coal series, as should also be true of 

 those in the green sand, it is probable that there has 

 here been some revolution, to add to all the others 

 formerly noticed, partially destructive of animal life, 

 though not attended with that reversal of positions 

 which marks those formerly discussed. And if this 

 be the explanation, it is probable that some marks of 

 revolution will hereafter be found in this place, by 

 those to whom I have thus pointed out the road which 

 they ought to follow. Should it also prove to be the 

 fact, if will be another revolution to add to those al- 

 ready demonstrated ; as, without some such explana- 

 tion, there must remain a serious blank in the Theory 

 of the Earth. 



The theory of the chalk becomes comparatively 

 easy, since it is but to repeat what was already said 

 respecting the calcareous strata following the red marl. 

 Yet with this exception. It is often a deep mass of 

 calcareous rock, without intervening argillaceous and 

 arenaceous strata. Its organic fossils show that it 

 was not a coral reef or island, the degradation of the 

 suprarnarine land ought to have been proceeding, and 

 yet it is what we see it. I have no solution for this 

 geological anomaly ; unless it be this. It is an ad- 

 mittedly partial rock, and considerably limited ; and I 

 can therefore suppose that it was formed in seas 

 bounding low lands instead of mountainous ones, from 

 which the deposition of arenaceous and argillaceous 

 materials might be so scanty as to suffer extensive calca- 

 reous unmixed deposits to be formed from the spoils 



