410 SKETCH TOWARDS A 



And such a sketch of the only general facts yet as- 

 certained, resting therefore on Evidence, while exclu- 

 ding what is at present unknown or conjectural, com- 

 prises the fundamental materials of all geological know- 

 ledge at present, as it also forms the basis for a Theory 

 of the Earth, such as that can now be inferred. It is 

 the Machinery of Nature in the regulation of the Globe, 

 as far as we can yet discern: or it includes the Secon- 

 dary'causes through which The Deity has proceeded, and 

 is proceeding, in the arrangement and government of 

 that Earth which has already constituted the habita- 

 tion of- different orders of animals, which, in compara- 

 tively recent times, has recieved Alan, among others, 

 and which is further destined to an office which we 

 cannot conjecture, however analogous we must sup- 

 pose it to that which is present and is past. I may 

 now therefore proceed. 



Passing at once from the Act of Creation, and from 

 the planetary arrangement of what is called Matter, 

 under a term which is admissible, however, but as an 

 abstract and mathematical one, the first condition of 

 the Earth which has been inferred, is that of a Gas- 

 eous sphere : while it is my business to state, that the 

 only evidence for this is derived from the analogy of 

 cornets, itself rather more inferential than proved, as 

 far as the study of these bodies has hitherto pro- 

 ceeded. But it must also be said, as corroborative of 

 such an inference, that the laws of the radiation of 

 heat, and those of chemical combination, do permit 

 the needful inference, that such a sphere might, or 

 must, finally become a fluid ; or at least a fluid glol.e 

 surrounded by an atmosphere. 



This, then, is the second presumed condition ; and 

 here also the evidence increases in value: while I may 

 notice, once for all, that I do not here intend to quote 

 authorities for any of these opinions, however weighty 



