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curve of an orbit around some remote center, the latter of 

 these astronomers betook himself to the examination of 

 ancient catalogues of stars, with a view to ascertain if there 

 was any discoverable district in the heavens where all the ap- 

 parent motions of the stars were such as to comply with the 

 conditions which must necessarily characterize a central region. 

 Such a district was found; and the star ALCYONE, in the 

 cluster Pleiades, was decided to be its center. Around this 

 point, therefore, our own sun, and the whole firmamental 

 cluster to which it belongs, were supposed to be revolving 

 with immense velocity, in orbits coincident with the general 

 plane of the Milky Way, and requiring no less than eighteen 

 millions of years to accomplish a single revolution ! 



Whatever diversity of opinion there may exist relative to 

 the legitimacy of the conclusion of Maedler, which locates the 

 center of alleged orbitual motion at the point occupied by the 

 star Alcyone, I believe it is now generally, if not universally 

 admitted by astronomers, that such orbitual motion does exist 

 around some center, not very remote from that region. 



The evidence upon this point greatly strengthens the 

 analogy which, of itself, points to the conclusion that those 

 isolated globular and other clusters of stars, situated in the re- 

 moter realms of space, and which appear to have been aggre- 

 gated by internal power of gravitation, are also scenes of per- 

 petual rotatory and orbitual motion. Did not these motions, 

 with their resultant centrifugal forces, exist to countervail, in 

 some degree, the force of internal gravity, those firmamental 

 clusters would doubtless exist in much more dense masses 

 than those in which they now appear. 



But if this conclusion thus approximates to a certainty, 

 there are facts which point to a still more extended appli- 

 cation of its principles. In the southern heavens, and quite 



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