NATURAL HISTORY OF CREATION ^3 



The nebular hypothesis, as it has been called, obtains 

 a remarkable support in what would at first seem to 

 militate against it — the existence in our firmament of 

 several thousands of solar systems, in which there are 

 more than one sun. These are called double and triple 

 stars. Some double stars, upon which careful observa- 

 tions have been made, are found to have a regular 

 revolutionary motion round each other in ellipses. This 

 kind of solar system has also been observed in what 

 appears to be its rudimental state, for there are examples 

 of nebulous stars containijig two and three nuclei in near 

 association. At a certain point in the confluence of the 

 matter of these nebulous stars, they would all become 

 involved in a common revolutionary motion, linked in- 

 extricably with each other, though it might be at 

 sufficient distances to allow of each distinct centre havinfir 



o 



afterwards its attendant planets. We have seen that 

 the law which causes rotation in the single solar masses, 

 is exactly the same which produces the familiar phe- 



Icss exact, but still very striking, in every other case. In those of 

 the planets he obtained for the tluration of the corresponding solar 

 rotations a value always a little less than their actual periodic times. 

 '•It is remarkable,'' says he, "that this ditference, though increasing 

 as the planet is more distant, preserves very nearly the same relation 

 to the corresponding periodic time, of which it commonly forms the 

 forty-fifth part " — showing, we may suppo.se, that only some small 

 elements of the question had been overlooked by the calculator. The 

 defect changes to an excess in the different systems of the sattdlites, 

 Avhere it is proportionally greater than in the planets, and unqcual in 

 the different systems. "From the whole of these comparisons," snys 

 he, " 1 deduced the following general result : — Sii])posing the mathe- 

 matical limit of the solar atmosphere successively extended to the 

 regions where the different planets are now found, the duration of the 

 sun's rotation was, at each of these epochs, sensibly equal to that 

 of tlie actual sidereal revolution of the corresponding planet ; and 

 ihfi same is true for each planetary atmosphere in relation to the 

 different satellites." — Couvs de P]uloso]_)Jite Ihsitif. 



