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so great perfection, as to give us a complete map of 

 the moon : yet do others (and not without reason) 

 doubt, Whether she has any atmosphere. And if 

 she has not any, she can have no rain or dews, nor 

 consequently, either seas or rivers. Sa that, afte? 

 all, we have nothing more than- mere conjectures, 

 concerning the nearest of all Jthe heavenly bodies* 



What is rt that contains them all in their orbits 1 

 And what is the principle of their motions ? By 

 what creative power, what outward or inward force, 

 are they thrown forward to such a point, and then 

 brought back again to a determinate distance from 

 the central fire ? Dr. Rogers has evidently demon- 

 strated, that no conjunction of the centrifugal and 

 centripetal force, can possibly account for this, or 

 ever cause any body to move in an ellipsis. Will 

 light, moving outward, and returning inward in the 

 form of spirit, account for thera ? Nay, if they take 

 away some, they plunge us into other difficulties, no 

 less considerable. So that there is reason to fear, 

 that even the Newtonian, yea, and Huickinsonian 

 system, however plausible and ingenious, and what- 

 ever advantage they may have in several particulars, 

 are yet no more capable of solid convincing proof, 

 than the Ptolemaic or Cartesian. 



But let us come to things that are nearer home, 

 and see what knowledge we have of them. And 

 how much do we know of that wonderful body, that 



