Intelligence and Miscellaneous Articles. 477 



the sword-shaped sign that was seen over Jerusalem at the com- 

 mencement of the war which ended in the destruction of the Holy- 

 City by Titus may have been the comet of Halley. 



The most ancient, and at the same time one of the most certain 

 apparitions of this body, took place in the year 11 b.c, reckoning 

 according to the manner of astronomers. It was observed, according 

 to Dion Cassius, under the consulate of M. Messala Barbatus and 

 P. Sulpicius Quirinus, before the death of Agrippa, and seemed as 

 though it were suspended over the city of Rome. The Chinese 

 found it on the 26th of August in Gemini ; it passed over this con» 

 stellation, north of Castor and Pollux, towards Leo and Virgo, 

 moving at the rate of 6° daily. Subsequently it passed near Arc- 

 turus and other stars in Bootes, and arrived in Ophiuchus and 

 Serpens. Fifty-six days after, August 26, it set with tt and a 

 Scorpii. 



After the publication of M. Biot's valuable details in the appendix 

 to the Connaissance des Temps for 1846, I attempted an orbit for 

 this comet, and was immediately struck with the similarity of the 

 elements to those of the comet of Halley. The only alteration 

 necessary appeared to be a diminution of the orbital inclination, 

 which, instead of 17°, would be more satisfactory at 8° or 10°. The 

 Chinese description cannot be strictly followed, or we should have 

 a very irregular path ; but I am satisfied that the elements of Hal- 

 ley's comet for perihelion, node and least distance, and an inclination 

 of 8°, will accord as well with the observations as any orbit can 

 possibly do. 



Previous to the year 11 b.c. the accounts of comets become so 

 vague that it would be vain to attempt to carry the inquiiy into 

 more remote antiquity. I think it will be deemed a fact of con- 

 siderable interest that the celebrated comet which bears the name of 

 our countryman Halley may be traced, in a pretty satisfactory- 

 manner, as far back as the year 1 1 before the Christian sera. For 

 this extensive knowledge of its probable history we are mainly in- 

 debted to the records preserved in the annals of the various reigning 

 dynasties in China. 



LXI. Intelligence and Miscellaneous Articles. 



ON BRONGNIARDITE, A NEW MINERAL. BY M. A. DAMOUR. 



jV/I CASTELNAU, during his last journey in America, collected 

 -i-^-l • a considerable number of mineral substances, which he depo- 

 sited with M. Damour to examine. Among these minerals, there was 

 a large specimen possessing metallic lustre, and described as an ore of 

 silver. As it did not possess any trace of crystallization, it was only 

 by analysis that it could be ascertained to be a distinct species, con- 

 sisting essentially of sulphur, antimony, lead and silver. Its prin- 

 cipal characters are these : — It has the metallic lustre peculiar to the 

 antimonio-sulphurets, such as polybasite, bournonite, zinkenite, &c. 

 Its fracture is uneven, and it has no cleavage. Its powder blackish- 



