y 1S86.0 



286 POOR 



ments in section 37. As these elements differed considerably 

 from those given in T,y, the perturbations by Jupiter for some 

 months previous to 1886 were recomputed with the new ele- 

 ments as a basis and the above elements were carried back to 

 1883 and were found to be : 



Elements VII. 

 Epoch, February 8.5 1883 



i«^ 1 1 2'^. 7340 

 Z=I47°48' 3i''-4 

 7r=: 188 36 49 .6 

 12= 186 36 9.2 

 ^^ 26 46 26 .3 ^ 

 «■= 6 3S 31 .8 



and the corresponding period of the comet is 



31-47 

 Julian years. 



This period, 31.47 years, is about two and a quarter years 

 longer than the definitive period obtained from Elements VI. 

 Thus the disturbances due to the figure of Jupiter had a decided 

 effect upon the motion of the nucleus of the comet ; an effect 

 large enough to sensibly modify the final conclusions in regard 

 to the identity of this comet with that of Lexell. These dis- 

 turbances and their effects are considerably larger than those 

 obtained in a former investigation.' This is due to the fact that 

 the comet approached Jupiter much more closely than was indi- 

 cated by the elements used in the former work. 



Even if we consider that the perturbations due to the figure 

 of Jupiter, as computed in section 34, as approximately correct 

 only, we can, nevertheless, safely conclude that the period of 

 this comet previous to 1883 was not less than 29.2 and not 

 greater than 31.5 years. 



1 " Researches upon Comet 1889 v," Asti'. Jour., 309, p. 177. 



