The Rev. Dr. Robinson on the Constant of Refraction. 



197 



l1Xdvi = — 28".25 

 K = 2.8861 



dB.= — V'.m 

 dfi=— 0.576 



31. o Cygni. 

 Twelve observations (1838. 533) give 

 8 = + 46° 13' 45". 59. 

 Precession = + 10". 648 ; sec var. = -f 0". 228 ; proper motion = + 0". 039. 



16 X </r = — 7".38 

 K = 3.7450 



6?B 



d}x : 



■0".46 

 0.160 



