190 COSMICAL ARRANGEMENTS. 



separation ? why should this nebulous matter 

 grow cooler and cooler ? why should it not re- 

 tain for ever the same degree of heat, whatever 

 heat be? If heat be a fluid, if to cool be to part 

 with this fluid, as many philosophers suppose, 

 what becomes of the fluid heat of the nebulous 

 matter, as the matter cools down ? Into what 

 unoccupied region does it find its way ? 



Innumerable questions of the same kind might 

 be asked, and the conclusion to be drawn is, 

 that every new physical theory which we include 

 in our view of the universe, involves us in new 

 difficulties and perplexities, if we try to erect it 

 into an ultimate and final account of the existence 

 and arrangement of the world in which we live. 

 With the evidence of such theories, considered as 

 scientific generalizations of ascertained facts, with 

 their claims to a place in our natural philosophy, 

 we have here nothing to do. But if they are put 

 forwards as a disclosure of the ultimate cause of 

 that which occurs, and as superseding the neces- 

 sity of looking further or higher ; if they claim a 

 place in our Natural Theology, as well as our 

 Natural Philosophy ; we conceive that their pre- 

 tensions will not bear a moment's examination. 



Leaving then to other persons and to future ages 

 to decide upon the scientific merits of the nebular 

 hypothesis, we conceive that the final fate of this 

 opinion can not, in sound reason, affect at all the 

 view which we have been endeavouring to illus- 



