THE STELLAR UNIVERSE. 



application so extensive, that it may be considered as proved by 

 the absence of all measureable displacement consequent upon the 

 orbital motion of the earth, that, a very few individual stars 

 excepted, the vast multitude of bodies which compose the uni- 

 verse, and which are nightly seen glittering in the firmament, 

 are at distances from the solar system greater than that which 

 would produce an apparent displacement amounting to the tenth of 

 a second. This limit of distance is therefore, ten parallactic units, 

 or about two million times the space between the earth and sun. 



Within this limit, or very little beyond it, nine stars have been 

 found to be placed, the nearest of which is that already mentioned, 

 of which Professor Henderson discovered the parallax. Those of 

 the others are due to the observations of Messrs. Bessel, Struve, 

 and Peters. In the following table the parallaxes of these stars 

 are given, with their corresponding distances, expressed in paral- 

 lactic units, and also in the larger unit presented by the distance 

 through which light moves in a year. 



The parallax of the first seven of these stars may be considered 

 as having been ascertained with tolerable certainty and precision. 

 The very small amount of that of the last two is such as to render 

 it more doubtful. What is certain, however, in relation to these 

 is, that the actual amount of their parallax is less than the tenth 

 of a second. 



TABLE. 

 Nine stars, ivith their ascertained parallax and corresponding distances. 



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