GENERAL MOVEMENT OF THE STARS. 227 



the first as the most probable cause, but believes, in the meantime, 

 that the conformity of movement is not so great for the stars as for 

 the planets of our solar system. 



According to the last researches of this astronomer, the central 

 point C and that towards which the Sun is moving are distant from 

 one another by an arc of .111° 30'. 7; and the proper movement of 

 Alcyone, taken in an inverse direction, conducts to a point situated 

 2°. 6 south of Q. According to the preceding calculations, these 

 numbers were, respectively, 113° 36' and 1°.5. If the position of Q 

 is well determined, it may be that the orbit described by our Sun is 

 not a circle, but an ellipse analogous to that of the planet Polymnia. 



The ideas promulged by M. Msedler from the time of his first re- 

 searches having encountered divers opponents, it was incumbent 

 upon him to reply in the later to those whose arguments merited 

 a serious attention. 



Sir John Herschel, in his Outlines of Astronomy, has objected to the 

 central point adopted by our author, that its position was unlikely, 

 because the group of the Pleiades does not project itself upon the 

 Milky Way. To this objection M. Mredler replies, that it is evident 

 that the point which is the common centre of gravity of the Milky 

 "Way, and the whole mass of stars which environ it, ought to be found 

 on the central plane of the ring constituting that, celestial belt, and 

 be projected on the plane from some point within its circuit. But if 

 our Sun be in that plane, it is apparent that the middle of the belt 

 must correspond to a great circle of the celestial sphere. Now, the 

 admirable charts published by Sir John Herschel himself show that 

 such is not the case in reality. The Milky Way is not at the same- 

 distance from the two poles of the equator, and it does not divide- 

 into two equal parts either that circle or the ecliptic. According to- 

 the researches of G. Fuss, the small circle to which the Milky Way 

 best corresponds, is distant 3^ degrees from the great circle to which 

 it is parallel. It follows from this that an interior point situated in 

 the plane of the ring, without being in the ring itself, cannot, from 

 the sun or the earth, be projected on the Milky Way, and would be 

 removed from it by an angle equal to that which a straight line 

 drawn from the sun to the central point would make with the plane 

 of the Milky circle. M. Argelander having previously, on the occa- 

 sion of his investigations of the proper movement of the Sun, thrown 

 out the opinion that the central point of the movement of the stars' 

 was perhaps in the constellation Perseus, M. Masdler had, in his; 

 first memoir, objected to this idea, the situation of that constellation 

 on the Milky Way. M. Argelander since then seems not to have 

 pursued his researches on this subject; and no one, to my knowledge 

 at least, has indicated any other point of the heavens for adoption as 

 the central point in preference to that situated in the Pleiades. 



Professor C. A. F. Peters, director of the observatory of Altona, and 

 present editor of the Astronomische Nacliricliten, had also, from the pub- 

 lication of M. Midler's first researches, raised some objections as to 

 their results. The latter has replied to them, (pages 254, 257, 14th 

 vol. of the Observations of Dorpat.) It would appear that this reply, with 



