156 cosmos. 



of 1092, 1181, and 1458), and in the absence of any s. ch record, as also 

 in the occasional addition, " the Ke-sing dissolved" (disappeared), there 

 is contained, if not au infallible, yet a very important criterion. Besides, 

 we must bear in mind that the light of the nucleus of all comets, wheth- 

 er with or without tails, is dull, never scintillates, and exhibits only a 

 mild radiance, while the luminous intensity of what the Chinese call 

 extraordinary (stranger) stars has been compared to that of Venus a 

 circumstance totally at variance with the nature of comets in general, 

 and especially of those without tails. The star which appeared in 134 

 B.C., under the old Han dynasty, may, as Sir.John Herschel remarks, 

 have been the new star of Hipparchus, which, according to the state- 

 ment of Pliny, induced him to commence his catalogue of the stars. 

 Delambre twice calls this statement a fiction, " une historiette." {Hist, 

 de VAstr. Anc, torn, i., p. 290; and Hist, de VAstr. Mod., torn, i., p. 186.) 

 Since, according to the express statement of Ptolemy {Almag., vii., p. 2, 

 13, Halma), the catalogue of Hipparchus belongs to the year 128 B.C., 

 and Hipparchus (as I have already remarked elsewhere) carried on his 

 observations in Rhodes (and perhaps also in Alexandria) from 162 to 

 127 B.C., there is nothing irreconcilable with this conjecture. It is very 



J)robable that the great Nicean astronomer had pursued his observations 

 or a considerable period before he conceived the idea of forming a reg- 

 ular catalogue. The words of Pliny, " suo revo genita," apply to the 

 whole term of his life. After the appearance of Tycho Brahe's star in 

 1572, it was much disputed whether the star of Hipparchus ought to be 

 classed among new stars, or comets without tails. Tycho Brahe himself 

 was of the former opinion {Progymn., p. 319-325). The words "ejus- 

 que motu addubitatiouem adductus" may undoubtedly lead to the sup- 

 position of a faint, or altogether tailless comet ; but Pliny's rhetorical 

 style admitted of such vagueness of expression. 



(b) A Chinese observation. It appeared in December, A.D. 123, 

 between a Herculis and a Ophiuchi. Ed. Biot, from Ma-tuan-lin. (It 

 is also asserted that a new star appeared in the reign of Hadrian, about 

 A.D. 130.) 



(r ) A singular and very large star. This also is taken from Ma-tuan- 

 lin, as well as the three following ones. 



It appeared on the 10th of December, 173, between a and /? Centauri 

 and at the end of eight months disappeared, after exhibiting the five 

 colors one after another. " Successivement' 11 is the term employed by 

 Ed. Biot in his translation. Such an expression would almost tend to 

 suggest a series of colors similar to those in the above-described star 

 of Tycho Brahe ; but Sir John Herschel more correctly takes it to mean 

 a colored scintillation {Outlines, p. 563), and Arago interprets in the same 

 way a nearly similar expression employed by Kepler when speaking 

 of the new star (1604) in Ophiuchus. ( Annuaire pour 1842, p. 347.) 



{d) This star was seen from March to August, 369. 



(e) Between A and <j> Sagittarii. In the Chinese Record it is expressly 

 observed, " where the star remained (i. c, without movement) from 

 April to July, 386." 



(/) A new star, close to a Aquihe. In the year 389, in the reign of 

 the Emperor Houorius, it shone forth with the brilliancy of Venus, ac- 

 cording to the statement of Cuspinianus, who had himself seen it. It 

 totally disappeared in about three weeks.* 



* Other accounts place the appearance in the year 388 or 398. 

 Jacques Cassini, EUmens d) 'Astronomie, 1740 ( Etoiles Noiivelles). p. 59. 



