NEW VARIABLE STAR, T CORONA. 283 



its changes have been comparatively slight. On the 20th 

 of August the intensity was at a minimum, being only i*2, 

 or y^(j of its amount on the 12th of May. 



An inspection of the curve of intensities suggests strongly 

 the idea that a force of an explosive character, such as 

 could residt only from the action of highly elastic gaseous 

 m^atter, had been in operation to produce the sudden in- 

 crease and subsequent rapid diminution of brightness 

 which had taken place ; but as some of the well-known 

 periodical variables occasionally exhibit an equal, and even 

 a greater rapidity of change, this view cannot at present 

 be received with much confidence ; and notwithstanding 

 the remarkable and highly interesting conclusions which 

 Mr. Huggins and Dr. W. A. Miller have drawn from the 

 results of their spectroscopic observations of this new vari- 

 able, we are constrained to admit that the cause of varia- 

 bility is still involved in the deepest mystery. 



The following Table contains the positions and magni- 

 tudes of the stars with which I have compared T Coronse 

 in the course of its changes. The positions are from the 

 ' Bonner Sternverzeichniss,' and the magnitudes are from 

 my own observations. The magnitudes of some of these 

 stars have been determined independently by Mr. Knott, 

 F.R.A.S., and it is satisfactory to me to find that our re- 

 sults are almost identical. 



n2 



