964 



to the plienonieiioii, such an explanation is for the present open to 

 grave snspicion. 



If, liowevei-, we do not accept an explanation by declination errors, 

 we innst atti'ibnte it to some cosmic plienomenon, the simplest being 

 to assume a general streaminjtj,- of the bright stars witli relation to 

 the faint ones, which would take place in a direction about at right 

 angles to the equator. 



At the same time it is clear that on this supposition we should 

 proceed from an assumption for which there is not a single ground 

 a priori, viz. that the etpiatorial motion may be regarded in its 

 entirety as a purely parallactic one, or else that for the equatorial 

 motion bright and faint stars may be considered as a homogeneous 

 whole differing only in distance. We should, therefore, also lose 

 the right to regard V^A'" + ^"' ^^ ^ measure for the distance. 



It will be unnecessary to say that such farreaching conclusions 

 must not be ventni-ed upon until the foundation for them has been 

 more tirraly laid. 



7. Terms jcith 2(t and 3«. 



The values for the coefficients of these terms ((/ sin 2« -|- e cos 2« + 

 -\- f sin S(( -\- g cos Sa in the R. A. and the same with dashes in the 

 Decl.) that were found from my two researches are as follows: 



Higher terms per century. 



or, expressed in another way ; 



in R.A. mean : + 0"06 cos 2 («—50°) + 0"40 cos S [a— 73°) 



in Decl. „ : + ü"45 cos 2 («—172°) -f 0"Ucos 3 («—30°) 



These results must be regarded as very uncertain. 



Gylde.n (V. J. S. 9, 180) found, from a few groups of stars with 



large P.M. : 



in R.A. : + 1"27 cos 2 («—99°) + 0"94 cos '6 («—45°) 



and Oppenheim (A.N. 188) from Gi-oombridge-stars : 



in R.A. : + 0"52 cos 2 («—74°) + 0"17 cos 3 («—23°). 

 A certain agreement may perhaps be traced here. 



