OF ARTS AND SCIENCES. 



263 



TABLE III. — Variation in Light of ( Geminori'm. 



There seems to be no evidence of the term n sin (2 v -\- /S) ; in other 

 words, the star appears to be a surface of revolution, one side being 

 about four-fifths of the brightness of the other. It is also possible 

 that the star may be elongated with axes in the ratio of four to five, 

 but of equal brightness on all sides, and that its time of revolution 

 is 20.32 days, or double the period commonly given. In this case 

 there may b6 a slight ditference in brightness at the alternate maxima 

 or minima which has hitherto escaped detection, because not antici- 

 pated. From the second formula we may infer that the true maxi- 

 mum and minimum precede that adopted by Argelander, by the angular 

 amount of 11.3°, or 7.6 hours. As this would only affect the light 

 curve by about a fiftieth of a magnitude, it might readily escape detec- 

 tion. It will be noticed that in this case the interval from maximum 

 to minimum is equal to that from minimum to maximum, instead of, as 

 is generally the case, exceeding it. A more direct determination of 

 the correction to the minimum may be found from the light curve, by 

 comparing the times at which the light is equal. 



In Table IV. are given the light in grades, the corresponding tinicis 



