422 THE BEAUTIES OF NATURE CHAP. 



father looked, and there was a faint star 

 due east from the bright one, and distant 

 about ten seconds. This was exactly the pre- 

 dicted direction for that time, though the dis- 

 coverers knew nothing of it. As the news 

 went round the world many observers turned 

 their attention to Sirius ; and it was then 

 found that, though it had never before been 

 noticed, the companion was really shown under 

 favourable circumstances by any powerful 

 telescope. It is, in fact, one-half of the size of 

 Sirius, though only yoljToth ^ the bright- 



ness." 



Stars are, we know, of different magni- 

 tudes and different degrees of glory. They 

 are also of different colours. Most, indeed, are 

 white, but some reddish, some ruddy, some 

 intensely red ; others, but fewer, green, blue, 

 or violet. It is possible that the compara- 

 tive rarity of these colours is due to the fact 

 that our atmosphere especially absorbs green 

 and blue, and it is remarkable that almost all 

 of the green, blue, or violet stars are one of 

 the pairs of a Double Star, and in every case 



1 Clarke, System of the Stars. 



