216 ASTRONOMY. 



sublimer views of the Deity, than any other subject af- 

 fords ; but It is not so well adapted, as some other subjects 

 are, to the purpose of argument. We are destitute of the 

 means of examining the constitution of the heavenly bodies. 

 The very simplicity of their appearance is against them. 

 We see nothing, but bright points, luminous circles, or the 

 phases of spheres reflecting the light which falls upon them. 

 Now we deduce designs from relation, aptitude, and cor- 

 respondence of parts. Some degree therefore of complex- 

 ity is necessary to render a subject fit for this species of 

 argument. But the heavenly bodies do not, except perhaps 

 in the instance of Saturn's ring, present themselves to our 

 observation as compounded of parts at all. This, which 

 may be a perfection in them, is a disadvantage t^ us, as 

 inquirers after their nature. They do not come within our 

 mechanics. 



And what we say of their forms is true of their motions. 

 Their motions are carried on without any sensible interme- 

 diate apparatus; whereby we are cut off from one principal 

 ground of argumentation, analogy. We have nothing 

 wherewith to compare them ; no invention, no discovery, 

 no operation or resource of art, which, in this respect, re- 

 sembles them. Even those things which are made to im- 

 itate and represent them, such as orreries, planetaria, celes- 

 tial globes, &c. bear no affinity to them, in the cause and 

 principle by which their motions are actuated. I can as- 

 sign for this difference a reason of utility, viz. a reason why 

 though the action o'i terrestrial hod'iQs upon each other be, 

 in almost all cases, through the intervention of solid or fluid 

 substances, yet central attraction does not operate in this 

 manner. It was necessary that the intervals between the 

 planetary orbs should be devoid of any inert matter, either 

 fluid or solid, because such an intervening substance would, 

 by its resistance, destroy those very motions, which attrac- 

 tion is employed to preserve. This may be a final cause 

 of the difference; but still the difference destroys the an- 

 alogy.* 



* The moon has no perceptible atmosphere ; and as no effects have 

 been observed like those which would be produced by vapours or ex- 

 halations from its surface, it is possible that there are no fluids upon 

 it. There is no reason, however, from these circumstances for deny- 

 ing the existence of sensitive beings upon it, although they must be 

 very differently constituted from ourselves, to whom air and water 

 are essentially necessary. Faxton. 



