VOL. XLV.] PHILOSOPHICAL TRANSACTIONS. 433 



41" 5', on March 27, 1727, it will agree within 1 seconds, with every one of 80 

 observations that have been made of this star. 



Having already given examples of stars lying near both the solstices and the 

 vernal equinox; I shall now add the observations of one that is not far from the 

 autumnal equinox, viz. -n Ursae Majoris, the brightest star in that part of the 

 heavens which approaches the zenith of Wansted within a degree ; and which, 

 by reason of its lustre and position, gave me the opportunity of making my series 

 of observations of it, more complete than of many others. This star was com- 

 pared with the point marked 39" 15', and was south of it as in the following 

 table ; in which it is seen, that the observations of the years 1 740 and 1 74 1 

 give the polar distances 3" greater, than the mean of the other years. Had there 

 been only a single observation taken in either of those years, part of this ap- 

 parent difference might have been supposed to arise from their uncertainty ; but 

 as there were 8 observations taken within a week, either before or after the 3d 

 day of June 1740, which agree well with each other; and 3 were made within 

 20 days in September 1741, which likewise corresponded with each other; lam 

 inclined to think that the beforementioned differences must be owing to some- 

 thing else, besides the error of the observations. This phenomenon therefore 

 may deserve the consideration of those gentlemen, who have employed their time 

 in making computations relating to the quantity of the effects which the power 

 of gravity may, on various occasions, produce. For I suspect, that the position, 

 of the moon's apogee, as well as of her nodes, has some relation to the apparent 

 motions of the stars that I am now speaking of. 



My series of observations of several stars abound, of late years, with so many 

 and long interruptions, that I cannot pretend to determine this point ; but pro- 

 bably the differences before taken notice of in the observations a Cassiopeae, and 

 some others, that I have found also among the observations of other stars, that 

 are not here recited, may be owing to such a cause ; which though it should not 

 have any large share of influence, may yet, in certain circumstances, discover a 



VOL. IX. 3 K 



