XVII.] 



VARIATIONS. 



231 



Now if Kirchhoff s statement be anything like a representation 

 of the truth there ought not to be any difference between 

 these intensities ; the line least intense in the photograph ought 

 to be least intense in Thalen's tables, and if it existed in the sun 

 at all, it ought to be least intense amongst the Fraunhofer lines, 

 but as a matter of fact, there is an absolute inversion. To take 

 instances; the cobalt line 41 20 '5 is four times as intense in the 

 photograph as in the sun; in the titanium line 3989*25 the inten- 

 sities are equal ; while in tungsten 4842 '0 they are inverted, being 



