Royal Astronomical Society. 



521 



scope of the Cambridge Observatory ; and the deduced places are as 

 follows : — 



Mr. Adams had previously computed the orbit by the method of 

 Olbers, on the supposition of its being a parabola, but he found that 

 the middle observation was so badly represented, that this hypothesis 

 could not be correct. He then proceeded to determine the elements 

 without making any hypothesis as to the conic section, and the re- 

 sulting elements are as follows : — 



Perihelion passage, 1843, October 26 d, 33 Greenwich mean time. 



o / 



Longitude of perihelion on the orbit... 54 27*8 \ From the equinox 



Longitude of ascending node 207 38*0/ of Dec. 5. 



Inclination to the ecliptic 10 48*9 



Perihelion distance 1*687 



Semi-axis major 3*444 



Eccentricity 0*510 



Periodic time 6*39 sidereal years. 



Motion direct. 



The author suggests that the comet may, perhaps, not have been 

 moving long in its present orbit, and that, as in the case of the comet 

 of 1770, we are indebted to the action of Jupiter for its present ap- 

 parition. In fact, supposing the above elements to be correct, the 

 aphelion distance is very nearly equal to the distance of Jupiter from 

 the sun : also the time of the comet's being in aphelion was 1843*8 

 — 3*2 = 1840*6, at which time its heliocentric longitude was 234° # 5 

 nearly, and the longitude of Jupiter was 231°*5 ; and, therefore, 

 since the inclination to the plane of Jupiter's orbit is also small, the 

 comet must have been very near Jupiter, when in aphelion, and 

 must have suffered very great perturbations, which may have ma- 

 terially changed the nature of its orbit. 



VII. Observations of the Comet of Faye. By C. Rumker, Esq. 

 Communicated by Dr. Lee. These will be found in the Monthly 

 Notices, as already referred to. 



VIII. Observations of the Comet of Faye, made at Starfield. By 

 W. Lassell, Esq. 



The author thinks that the observations given may be relied upon 

 to within one second of time, and eight or ten seconds of declination. 

 They were made with the 9-feet equatorial, used differentially, com- 

 paring the place of the comet with the stars 23 and 30 Orionis, and 

 one or two small stars near them. 



The following are the resulting places : — 



