965 



8. Rotation according to Schönfeld. 



Schönfeld's equations (V. J. S 17, 256) show that tlie values of' 

 the precession-constant /), deduced from a and ff, are vitiated about 

 equally by a general rotation of the stars with the axis of rotation 

 at right angles to the plane of the galactic, so that a comparison 

 of these results cannot teach us anything on this point. It appears 

 that the rotation constant dl can then only be determined by a 

 comparison of the values of ]" deduced from « and 6. In this way 

 I have calculated the values for dl which would follow from the 

 material at our disposal. 



The results are the following : 



Results for the rotation constant dl 



Nothing can therefore be deduced with any probability from the 

 material here collected. 



Besides the supposition of a constant (//, that of a (// depending 

 upon the distance, might be also examined. 



9. The systematic "proper-motions of the 2"^ kind." 

 It is my intention to investigate these in the following way. From 

 the total P.M. of the separate stars the systematic "P.M. of the J*' 

 kind" discussed above is subtracted. The' differences thus obtained 

 will then be examined as to preferential directions, etc. 



I have already made a beginning with this investigation, accord- 

 ing to a method partly graphical and partly analytic. I hope soon 

 to be able to publish the results. 



