On the Chemical Classification of the Stars. 



Aldebarian. 



Predominant. — Proto-calcium, arc 

 lines of iron, calcium, and manganese, 

 proto-strontiuni, hydrogen. 



Fainter. — Proto-iron and proto-tita- 

 nium. 



Antarian. 

 Predominant. — Fhitings of manga- 

 nese. 



Fainter. — Arc lines of metallic ele- 

 ments. 



191 



Arcturian. 

 Same as Aldebarian. 



Piscian. - 



Predominant. — Mutings of carbon. 

 Fainter. — Arc lines of metallic ele- 

 ments. 



We may take for granted that as time goes on new intermediate 

 genera will require to be established ; the proposed classification lends 

 itself conveniently to this, as there are no numerical relations to be 

 disturbed. 



A still more general chemical classification is the following, it being 

 understood that in it only the most predominant chemical features are 

 considered, and that there is no sharp line of separation between these 

 larger groups. The peculiar position of calcium and magnesium renders 

 this caveat the more necessary. 



Classification of Stars. 

 Highest temperature. 



f Proto-hydrogen stars 

 Gaseous stars < 



Cleveite-gas stars ^ Saurian 

 Eigelian. 



Proto-metallic stars <l Cygnian. 



f Argonian. 

 \ Alnitamian. 



Metallic stars 



{Polar ian. 

 Aldebarian. 

 Stars with fluted spectra Antarian. 



Lowest temperature. 



Achernian. 

 Algolian. 

 Markabian. 



Sirian. 

 Procyonian, 

 Arcturian. 

 Piscian. 



The detailed chemical facts to be gathered from the definitions of 

 the several genera indicate many important differences between the 

 order of appearance of the chemical substances in the atmospheres of the 

 stars and that suggested by the hypothetical " periodic law." Special 

 investigations are in progress by which it is hoped some light may be 

 thrown on this and other points of a like nature. 



