MOVEMENTS IN THE STAR-DEPTHS. 67 



the same rate ; lie would be receding from all stars 

 lying in the opposite direction at the same rate; and 

 he would be approaching or receding from stars lying 

 in opposite directions at a less rate (readily calculable). 

 A certain half of the heavens would contain all the 

 stars which the sun was approaching ; the other half 

 would contain all the stars from which he was receding ; 

 and the circle separating these halves would mark the 

 place of stars which the sun was neither receding from 

 nor approaching. But nothing of this sort can be 

 recognised in the observed stellar rates of approach 

 and recession. Sirius (which lies nearly opposite to 

 Hercules) is receding at the rate of about 20 miles per 

 second; but Vega (which lies close to Hercules), instead 

 of approaching at about the same rate, is actually 

 approaching at the rate of about 50 miles per second. 

 Castor, which is very near the border line between the 

 two hemispheres just mentioned, and should therefore 

 neither be approaching nor receding, is in fact reced 

 ing at the rate of about 25 miles per second ; while 

 Pollux, though similarly placed, is approaching the sun 

 at the rate of about 49 miles per second. Again, of the 

 seven bright stars forming Charles s Wain, six are 

 approaching (five of them at the rate of about 20 miles 

 per second), while the seventh is receding at a rate 

 probably exceeding 50 miles per second. 



Thus we see that the sun cannot be regarded as an 

 orb moving within the scheme of stars, and by his own 

 movement causing the chief apparent motions of the 

 surrounding orbs. His motion is but part of a grand 



F 2 



