!34d~ 3tr. Pond on the Changes in the Declinations of [Oct. 



peirfect, aiid tliAt 1 might repose the greatest confidence in every 

 i-fesult it gave. 



Several stars, and particularly those most discordant, I have 

 observed by this new method, and find their places, without any 

 exception, to agree within a fraction of a second, with those 

 determined by direct measurement from the pole. 



Presuming that the observations* which accompany this 

 paper will remove every shadow of a doubt as to the accuracy of 

 the instrument, I shall now proceed to state, in as few words as 

 possible, the nature of the changes which appear to me to have 

 taken place since the year 1812. 



If Bradley's catalogue of stars for the year 1756, be com- 

 pared with the Greenwich catalogue for 1813, it will be possible 

 to deduce the annual variation for each star for the mean period, 

 or for the year 1784, on the supposition of uniformity in the 

 proper motion of each star; then allowing for the change of 

 precession for each star, a catalogue may be computed for any 

 distant period ; as for example, the present year 1822. Suppose 

 such a catalogue computed, which I have named a predicted 

 catalogue ; then, if this be compared with the observed cata- 

 logue for the same year, the following differences will be found 

 to subsist between them. 



The general tendency of all the stars will be to appear to the 

 south of their predicted places, and this tendency seems to be 

 greater in southern than in northern stars ; if any star be found 

 north of its predicted place, it will always be a star north of the 

 i^enith, and the quantity of its motion extremely small. There 

 may be observed a much greater tendency to southern motion in 

 some parts of the heavens than in opposite or distant parts as 

 to right ascension, and in much the greater portion of the 

 heavens the southern motion seems to prevail. A southern star, 

 as Sirius, situated in that part of the heavens most favourable 

 for southern motion, will be found more to the south of its pre* 

 dieted place than Antares, situated in the part least favourable 

 for southern motion, though it is itself more southward. 



Several stars have moved more from their predicted places 

 than other neighbouring stars ; when this happens, the motion 

 is always southward ; 1 have yet met with no exception to this 

 rule ; not a single star can be found having an extra tendency 

 to northern motion ; and indeed the northern motion in any 

 star is so very small, that it would never have excited attention. 



A very great deviation will be found in three very bright stars, 

 Capella, Procyon, and Sirius : the proper motion of each of 

 these is southward ; it therefore follows that these proper 

 motions are accelerated. The proper motion of Arcturus is very 

 great, and likewise southward. It is situated in that part of the 



• These observations arc given, in the Transactions, in a copious appendix of tables 

 to this and the two succeeding papers, whitli,on account of its length, we arc compelled 

 to omit, — E(kt, 



