176 G. H. KNIBBS. 



occupied by the light in passing from a planet as Jupiter to the 

 earth, ought to vary as the planet moves through different signs 

 of the zodiac. Hence he thought it might be possible to at least 

 detect the existence of the motion in this way. 1 



(75) Lagrange, C, 1880. —Lagrange in 1880 contributed an 

 article to " Oiel et Terre," on the apex of the solar motion through 

 space. 2 % 



(75a) Schonfeld, 1882.— -In 1882, Schonfeld introduced into 

 the discussion of the sun's motion in space a term representing a 

 possible rotation in the plane of the Milky- Way. 3 [Not having 

 access to the volume of the quarterly journal of the Astronomische 

 Gesellschaft containing his treatise, I am unable to more fully 

 refer to it.] 



(76) Rancken, 1882.— Rancken of Brahestad, Finland, 4 in 1882 

 adopting Gylden's hypothesis as to the parallax of the stars, 5 and 

 employing Argelander's proper motions of 250 stars, 6 and Leo de 

 Ball's proper motions of 80 southern stars, 7 computed the direction 

 and quantity of the solar motion from the P.Ms, in right ascension, 

 and in declination, considered independently. Denoting for 

 brevity's sake, the computation from the former by R.A'., and 

 from the latter by R.A. and D.; and putting E for the annual 

 motion in terms of the mean distance of the earth from the sun ; 

 he obtained the results hereunder : — 



From Argelander's P.Ms. — 



R.A'. = 285-°0; R.A. = 284-°6, 13.= + 37'°5, E = 10-85 

 From de Ball's P.Ms.— 



R.A. = 273-°8; R.A. = 244-°l, D. = + 17-°5, E= 4-59 



1 Proc. Roy. Soc, Lond., Vol. xxx., pp. 108-110, 1879. 



2 Le point fixe, i., p. 217, 1880. 



3 Vierteljahrsschrift d. Astr. Ges., Bd. xvn., pp. 256 et seq., 1882. 



4 Ueber die Eigenbewegung der Fixsterne. — Astr. Nach. Bd. civ., pp. 

 149 - 156, 1882. 



5 Vierteljahrsschrift der Astron. Gesell., Bd. xn., Heft 4. Gylden's 

 hypothesis makes the parallax a function both of magnitude and proper- 

 motion. 



6 Bonner Beobachtungen, Bd. vn. 



7 Inaugural-dissertation, 1877. 



