

THE NEW STAR WHICH FADED INTO STAR-MIST. 127 



spectrum, including the bright lines which, instead of fading 

 out, shone with at least relatively superior brightness as the 

 star faded from view. The theory that, on the contrary, 

 the matter giving these more persistent lines was that whose 

 emission caused the star's increase of lustre, seems at least 

 not proven, and I would go so far as to say that it accords 

 ill with the evidence. 



The question, be it noted, is simply whether we should 

 regard the kind of light which lasts longest in this star as it 

 fades out of view as more probably belonging to the star's 

 abnormal brightness or to its normal luminosity. It seems 

 to me there can be little doubt that the persistence of this 

 part of the star's light points to the latter rather than to the 

 former view. 



Let it also be noticed that the changes which had been 

 observed thus far were altogether unlike those which had 

 been observed in the case of the star in the Northern Crown, 

 and therefore cannot justly be regarded as pointing to the 

 same explanation. As the star in the Crown faded from 

 view, the bright lines indicative of glowing hydrogen died 

 out, and only the ordinary stellar spectrum remained. In the 

 case of the star in the Swan, the part of the spectrum corres- 

 ponding to stellar light faded gradually from view, and bright 

 lines only were left, at least as conspicuous parts of the star's 

 spectrum. So that whereas one orb seemed to have faded 

 into a faint star, the other seemed fading out into a nebula 

 not merely passing into such a condition as to shine with 

 light indicative of gaseity, but actually so changing as to 

 shine with light of the very tints (or, more strictly, of the 

 very wave-lengths) observed in all the gaseous nebulae. 



The strange eventful history of the new star in Cygnus 

 did not end here, however. We may even say, indeed, 

 that it has not ended yet But another chapter can already 

 be written. 



Vogel ceased from observing the star in March, precisely 

 when observation seemed to promise the most interesting 

 results. At most other observatories, also, no observations 



