672 



ing values of <i A and d D applied as corrections to the assumed 

 values of A and D. The results are as follows : — the whole of the 

 eighty-one equations give (for 1790) as co-ordinates of the point 

 towards which the sun's motion is directed, 



i?l=263° 38'-0 + 5° 14'-5 ; Dec.= -l-37^ 15'-0+6° l7'-6. 



But two of the stars compared with Lacaille move in a direction so 

 nearly opposite to that of their motion on the assumed hypothesis, 

 that (in one case especially) a slight error of observation would 

 change the sign of 7i in the equations of condition. It therefore 

 appears necessary to reject those two stars ; and a further reason 

 for rejecting them is, that they are both situated within 8° of the 

 pole, in which position Lacaille's determination of the right ascen- 

 sion is probably not to be depended upon. Setting aside, there- 

 fore, the two stars in question, the remaining seventy-nine equa- 

 tions give 



^=256° 51''5 + 4° 45'-l ; Dec.= -}-34.^ U^'-34:5° 36''2. 



The author further observes, that one of the stars compared with 

 Bradley's catalogue is also remarkable as appearing to move in a 

 direction nearly opposite to the mean direction of the whole, and 

 that if this star be rejected also on account of the great probability 

 there is that the parallactic motion is in this case concealed by the 

 larger proper motion of the star itself in an opposite direction, the 

 co-ordinates of the solar apex become 



^=259°47H + 4°31'-9; Dec.= +34° 19'-5 + 5° 17'-7, 



a result differing less than a degree either in right ascension or de* 

 clination from the mean, as above stated, of the three previous de- 

 terminations. 



