214 G. H. KNIBBS. 



of stars, 1 the results being as follows : — 



Group (a) (b) (c) (d) Mean 



R.A. = 268-°4 270-°9 270-°9 286-°2 274-°l 



Epoch 1800? 



(70a) Gylde'n, 1877.— In his 'Elements of Astronomy,' Gylden 

 gives for the R.A. of the direction of the sun's motion. 2 

 R.A. = 260-°5. Epoch 1800. 



(84a) Ubaghs, 1887.— In. February 1887 Ubaghs discussed 

 more fully the velocity of the solar motion. From a group of 34 

 near stars the result was practically zero, while from a larger 

 group of 163 it amounted only to 0*05 of the radius of the 

 terrestrial orbit, i.e., say 0*15 miles per second. 3 



(85a) Eastman, 1889. — The general trend of the investigation 

 of the solar motion was the subject of a presidential address by 

 Eastman to the Philosophical Society of Washington in December 

 1889. 4 He discusses somewhat fully the intrinsic difficulties of 

 the problem, gives a sketch of the history of the inquiry, and a 

 list of some of the results of previous investigators. Using the 

 known parallaxes of 46 stars, arranging them in groups of nine 

 according to the magnitudes of their proper motions, he obtained 

 the following results : — 



No. of 

 Stars. 



9 

 9 

 9 

 9 

 10 



from which, so far as the evidence goes, it appears that the fainter, 



rather than the brighter stars are nearest our system ! This 



x Anty dningar om lagbundenhet i stjernornas rorelser. — Oefversigt kon. 

 Vetens. Akad. Forhandl., 1871. Arg. xxvm., pp. 947 - 960. 



2 Grundlehren der Astronomie, Leipzig, 1877, p. 388. Quoted by 

 Eastman, see (85aJ. 



3 Determination de la direction et de la vitesse du translation du 

 systeme solaire dans Tespace. — Bull. l'Acad. Eoy. Belg. 3me ser. t. xiii., 

 pp. 66 - 68, 1887. 



4 Solar and stellar proper motions. — Bull. Phil. Soc, Washington, 

 Vol. xi., pp. 143 - 171, 1888 - 1891. 



jan Mag. 



Mean P.M. 



Parallax. 



557 



493 



0-"32 



5-59 



2-33 



0-20 



3-37 



1-04 



0-20 



2-36 



•38 



0-16 



2-84 



•06 



0-13 



