OF ARTS AND SCIENCES. 



171 



Classifying according to magnitude of probable error (1),— 



Class (a). All stars AA more than once observed. 

 All stars AB more than twice observed. 



20 pairs of class (a) 38°59'41''61 



PEoflpair(l) ±0.31 



(2) ±0.468 



Class ifi). All stars AB twice observed. 



All stars BB more than twice observed. 



8 pairs of class (j8) 38«'59'41"41 



PEoflpair(l) ±0.38 



(2) ±0.28 



Class (7) All stars once observed 38°59'4F'46 



All stars AC, BC. 



23 pairs of class (7) 



PEoflpair(l) ±0.46 



(2) ±0.606 



