196 G. H. KNIBBS. 



move in excentric paths about the centre of the galaxy, introduced 

 into his equations terms representing the galactocentric coordinates 

 of the stars' positions, and investigated the evidence for such 

 motion. 



Dividing the proper motions of 996 available stars into three 

 groups according to their quantity, and into three classes accord- 

 ing to the magnitudes of the stars — as shewn hereunder — the 

 following results were obtained : — 

 Group. P.M. *%£ R.A. D. Mean P.M. Mean Mag. 



I. 0-16 -0-32 551 284-4 +41-5 0-229 6-34 



II. 0-32-0-64 339 275-7 41-9 0-433 6-70 



III. 0-64-1-28 106 287-7 33-1 0-850 6-38 



Class. Magnitude. l t ° ar ° s f R.A. D. Mean P.M. Mean Mag. 



1. 7-6- < 284 286-7 46-9 0'384 8-18 



2. 5-6-7-5 473 290-7 37-5 0-357 6-63 



3. 1- -5-5 238 263-8 31-1 0358 4-12 



These should give consistent results, if stellar distance be a 

 function of the proper motion in the first series, or a function of 

 the magnitude in the second series. 



Rearranging the stars in three divisions (a), (b), (c) by applying 

 Gylden's hypothesis as to parallax, previously referred to (see 1894), 

 the results then become : — 

 Divisi0I1 Parallax. l t ar ° s ? R.A. D. Mean P.M. Mean Mag. 



(a) -02 --04 404 287-4 +45-0 o"233 7-12 



(b) -04 -06 348 282-2 43-5 -387 6-82 



(c) -06 -12 243 280-2 335 -552 4-89 



These all shew a progression of the values for the apex-point, 

 standing out the more clearly when stars of equal P.M. are classed 

 according to brightness, or when stars of equal brightness are 

 classed according to their P.M. Thus for example, the number 

 also being thereby reduced as shewn, the results become — 



7T 



ass 



. Magnitude. 



No. of 



Stars. 



R.A. 



D. 



Mean 

 P.M. 



Mean 

 Mag. 



Mean \ 



1. 



7-6- < 



139 



305-3 



560 



0-237 



8-17 



0'026 



2. 



5-6-7-5 



265 



281-8 



38-3 



0-231 



6-58 



•034 



3. 



1- -5-5 



146 



276-2 



30-9 



0-219 



4-19 



•067 



that is to say the progression referred to is still more conspicuous. 



