SOLAR MOTiojr: 271 



ticularity in the direction and comparative velocities in the investigation 

 largest stars that must not be overlooked. Four of them, of the proper 

 Rigel, a Orionis, Spica, and Antares, have a motion to- ^^^'*°" °^ ^^^ 

 ward that part of the heavens in which the solar apex is 

 placed, and their motions are very slow. Three other 

 stars of the 1st magnitude, Arcturus, Procyon, and Si- 

 rius, move toward the opposite part of the heavens, and 

 their motions, on the contrary, are very quick. 



The direction of the motion of Aldebaran, compared 

 with its small velocity, is no less remarkable ; and seems 

 to be contrary to what has been pointed out with the 

 three last mentioned stars; we shall however soon have 

 an opportunity of showing that it is perfectly consistent 

 with the principles of the solar motion. 



The Solar Motion and its Direction assigned in the first 

 Part of this Paper are confirmed by the Phenomena 

 attending the observed Motions of the 36 Stars, 



An application of some of the foregoing remarks will 

 be our next subject; and I believe it will be found, that 

 in the first place they point out the expediency of a solar 

 motion. That next to this they also direct us to the 

 situation of the apex of this motion: and lastly, that they 

 will assist us in finding out the quantity requisite for giv- 

 ing us the most satisfactory explanation of the pheno- 

 mena of the observed proper motions of the stars. 



In examining the second figure, it has been shown that 

 no less than six stars of the first magnitude, namely, Ca- 

 pella, Lyra, Rigel, a Orionis, Aldebaran, and Spica, 

 have less velocity than nine or ten much smaller stars. 

 Aldebaran and a Orionis indeed have so little motion that 

 there are but three stars in all the 36 that have less. But 

 the situation of these bright stars, from their nearness, 

 must be favourable to our perceiving their real motions 

 if they had any, unless they were counteracted by some 

 general cause that might render them less conspicuous. 

 Now to suppose that the largest stars should really have 

 the smallest motions, is too singular an opinion to be 

 maintained; it follows, therefore, that the apparently 

 small -m^tious of these large stajs is owing to some gene- 

 ral 



