Further Observations on Nova Persei. 233 



graphed on several evenings shows that this structure has been under- 

 going changes. 



The annexed figure (fig. 1) gives light curves showing the variation 



FiGh 1. — Light curve of H/3 (6-inch objective prism). 



in the loci of intensity of the line H/3, as photographed with the 6-inch 

 prismatic camera. These curves were plotted by Messrs. Baxandall 

 and Shaw independently of each other, and I have satisfied myself of 

 their accuracy. It will be seen that on February 25th there were three 

 points of maximum luminosity, the two maxima on the blue side being 

 of equal intensity, and greater than the third on the red side. By 

 March 1 the centre one had been greatly reduced in intensity, and on 

 the 3rd it had been broken up into two portions, thus making four 

 distinct maxima. 



Rough measures made on the relative positions of these points of 

 maxima show that the difference of velocity indicated between the two 

 external maxima is nearly 1,000 miles per second, while that between 



