OF THE COSMOS. DISTANCE OF FIXED STARS. 191 



motion 6 V *974*), are, the one 3, and the other 4 times as far 

 from the Sun as a Centauri, which has a proper motion 

 of 3' x *58. Yolume, mass, intensity of light, proper motion 

 ( 316 ), and distance from our solar system, are certainly in 

 very various and complicated relations to each other. Al- 

 though, therefore, it may be generally probable that the 

 brightest stars are the nearest, yet there may be individual 

 cases of very remote small stars whose photospheres and 

 surfaces may, from the nature of their physical constitution, 

 support a very intense luminous process. Stars, which on 

 account of their brightness we reckon as belonging to the 

 1st magnitude, may thus be really more distant from us 

 than stars which we call of the 4th, 5th, or 6th magni- 

 tudes. If we descend from the consideration of the great 

 sidereal stratum, of which our solar system is a part, to the 

 subordinate particular system of our planetary world, and 

 step by step, still lower, to the systems of Jupiter and 

 Saturn with their respective satellites, we see central bodies 

 surrounded by masses in which the succession of magni- 

 tudes and of intensities of reflected light does not appear 

 to depend at all on distance. The immediate connection 

 subsisting between our direct knowledge, still so slight, of 

 the parallaxes of stars, and our knowledge of the entire 

 structural form of the universe, gives a peculiar interest 

 and charm to considerations which relate to the distance 

 of the fixed stars. 



Human ingenuity has devised for this class of investiga- 

 tions a method quite different from those usually employed ; 

 it is founded on the velocity of light, and deserves to be 

 briefly noticed in this place. Savary, of whom the physical 

 sciences have been too early deprived, has shown how, in 



