xxiv. New Zealand Institute. 



and a half years and seventy-six years respectively — the elements of 

 the motion of others are not sufficiently known to admit of their 

 return being predicted. 



Those who recollect the great comet of 1843 confess that it hardly, 

 if at all, surpassed the one of last year in brilliancy, although some 

 maintain that it exceeded it in the apparent length of its tail as seen 

 from the earth. The large majority of those now living, however, 

 have never seen anything that can be compared to the magnificent 

 comet of 1882. It was visible from all quarters of the globe, and so 

 brilliant as to be seen with the naked eye at noon in a clear sky. 

 On the 17th of September a unique observation was made at the 

 Cape, where the comet was seen to pass right up to the sun's limb, 

 after which it became invisible, not intercepting the faintest portion 

 of the sun's light. The following morning it passed its perihelion 

 passage so close as to be within the region beyond which the great 

 solar jets of incandescent hydrogen (to which I will presently refer 

 in another connection) are often seen to extend. It must, whilst in 

 that position, have been exposed to a heat so intense, that rock-crystal, 

 agate, or the most infusible substance we know of, would have been 

 vapourized. The gigantic tail covered a space at least as long as 

 the distance between the earth and the sun, and, although apparently 

 of very small substantiality, several observers report that they saw 

 distinctly in the sky the black shadow cast by the tail of the comet. 



The question as to the relations between the comets of 18-13, 

 1880, and 1882 is one of great interest. According to Mr. Chandler, 

 the orbit of the comet of last year is such as to be quite inconsistent 

 with a short period of revolution, and, if so, it must be distinct from 

 either of the earlier comets, — or from the earlier comet, supposing 

 those of 1843 and 1880 to be identical. 



Another view has lately been put forward in the " Observatory," 

 from which I quote the following words : — " The physical appearance 

 of the comet, which like that of 1843, and unlike that of 1880, showed 

 at first a decided nucleus, together with the intimation of a period 

 very considerably greater than that of the interval from the 27th 

 January, 1880, the date of perihelion of the 1880 comet," to September, 

 1882, " suggest that perhaps the 1843 comet suffered disintegration 

 when at its nearest approach, and that the 1880 comet was a portion 

 of its less condensed material, whilst the body of the comet with the 

 principal nucleus, suffering less retardation than the separated part, 

 has taken two and a half years longer to perform a revolution." 



The latest, and I understand the most accurate, calculations, how- 

 ever, attribute to the orbit of the comet of 1882 a period of 840 years, 

 so that the last time it passed round the sun was about the year 1140, 

 in the days of King Stephen. 



