WRITINGS OF JAMES SMITHSON. 105 



rest, while any unsupported assumptions are involved in it. 



If I rightly apprehend Mr. Penn's ideas, they are these : 



Secondary limestones were originally in a soft state. 



The waters of the deluge while elevated above England, 

 deposited on it a layer, or bed, of "a soft and plastic" cal- 

 careous matter. 



On their departure from the earth, by flowing away to- 

 wards the north, they floated over England the carcases of 

 a number of tropical animals, clustered together into great 

 masses. 



These masses became buried in the calcareous mud. 



On the sinking of the waters of the deluge below the 

 surface of England, the bed of calcareous mud began to dry, 

 and on doing so completely, became the present Kirkdale 

 rock. 



The clustered animal bodies enclosed in the calcareous 

 paste, by putrifying, evolved a great quantity of gas, which 

 forced the limestone paste in all directions from them, and 

 thus generated the Cave in which Mr. Buckland found their 

 bones. 



Soft State of Secondary Limestones. 



That secondary limestones have been in a state to admit 

 foreign bodies into their substance, their existence in it is 

 evidence. 



Every shell and stone on the beach tells by its rounded 

 form the attrition to which it is subject at each flood and 

 ebb of the tide ; and that a subtil powder is abraded from 

 it which is collected somewhere. 



From the immense multitudes of marine bodies which 

 exist in some of these limestones, from others consisting in 

 fact entirely of them, from in general little or nothing but 

 calcareous matter being present, it becomes highly probable 

 that it is to the calcareous part of marine animals, more or 

 less comminuted, that secondary limestones owe their ori- 

 gin. 



