and the actual Forms of Inorganic Bodies. 135^ 



called an aqueous tissue, preponderates over the carbonaceous, 

 as is the case in most monocotyledonous species, traces of the 

 same forms are constantly occurring. But in this place, as we 

 proposed to confine our regards to the inorganic kingdom, more 

 need not be said on that subject. 



Extending our observations from the aqueous strata to those 

 which are permanently solid, analogous phenomena everywhere 

 present themselves to view. Those strata, indeed, which are 

 of more recent deposition, which have been aggregated by their 

 weight merely, and consist of the debris of older ones, are still, in 

 most cases, in a muddy and mechanical state, their integration 

 l^eing still incomplete. But, as we go deeper into the geological se- 

 ries, and come into the region of those rocks which have continued 

 for a longer time unbroken, we find that they have all, to a 

 greater or less extent, acquired a crystalline structure. And that 

 rocks, now in a mechanical state, are ever tending to pass more 

 and more into the crystalline, as many arguments might be 

 brought forward as the case admits of. If one introduced into 

 a saline solution pr mass of mobile particles, as, for instance, 

 into a solution of alum, or a cask of sugar, any body possessing 

 a permanent form, such as a little crystal of alum, or sugar, or 

 even a little bit of stone, or chip of wood, it is well known that 

 it will become a nucleus, around which crystallization will take 

 place, which had otherwise required a longer time to be deve- 

 loped; and no one will doubt, that, unless prevented, this pro- 

 cess of crystallization once begun, will extend itself more and 

 more, till some circumstance prescribes a limit to it. Now, 

 phenomena perfectly analogous to these are presented in those 

 rocks whose matter occurs, in the present era of the world, in a 

 mechanical state. Thus in a bed of chalk, where an organism 

 has been inclosed, the matter within the organism and around 

 it (unless the bed be very recent), is invariably more highly 

 crystalline than the other parts. Nay, in certain mechanical 

 strata, even balls of air, having been included, or somehow ge- 

 nerated, have, like any other dissimilar bodies, served as nuclei, 

 where the* process of crystallization has commenced ; and the 

 cavities they occasion are not only often drusy in their interior, 

 but the rock around them is often sensibly more crystalline 

 than the general character of the bed. And besides such cases, 



