132 VARIABLE STARS IN SOUTHERN HEMISPHERE, 



escaped the knowledge of Mr. Hind, the celebrated Astronomer 

 and superintendent of the Nautical Almanac, as to be still 

 denoted in that valuable work as a star of the second magnitude. 

 Several stars of a character far less marked are designated in 

 that work as variable. The other variable stars of high south 

 declination are Kappa (K) Corona? Australis, and B.A. C. 5656. 

 The former was discovered to be variable by Halley, in 1676. 

 The latter is variable on the authority of the British Association 

 catalogue : it is one of the stars forming the tail of the Scorpion, 

 and is, like Eta (T?) Argus, situated within the Via Lactea. I 

 have no knowledge of its period and limits of variation, It does 

 not appear to have been observed by Lacaille. 



II. The next subject to which I would direct your attention 

 is the examination of stars suspected to be variable. In the 

 Astronomische Nachrichten, No. 1311, May 29, 1861, is a com- 

 munication from M. Secchi, an Astronomer at Rome, from which 

 I give the following extract : 



" On m'ecrit du Chili que 1'etoile Canopus brille actuellement 

 d'un eclat qui plusieurs fois est superieur a Sirius : cela prouverait 

 une variabilite." 



It appears, then, that our bright star Canopus has surpassed 

 Sirius even in splendour. M. Secchi does not give his authority, 

 nor is his statement accompanied by any definite observations. 

 I have not hitherto paid much attention to the subject of variable 

 stars, but it occurs to me that I have often been struck with the 

 great brilliancy of Canopus, and I believe I have even given 

 expression to my thoughts on the subject. I have not, however, 

 instituted any comparisons between it and Sirius. It was only 

 very recently that I became aware of M. Secchi's communication, 

 so that I was unable to verify the statement, Sirius being then too 

 near the -vapours of the horizon to afford a trustworthy com- 

 parison. I trust to be able to make some comparisons in the 

 course of a short time. Canopus may, therefore, at least be re- 

 garded as belonging to the class of stars suspected to be variable. 

 There are some circumstances connected with the conspicuous 

 star Beta (/9) Argus, which should make it the subject of careful 

 observation. The catalogue of the British Association imitating, 

 I presume, that of Lacaille, represents this star as of the first 



