INORGANIC EVOLUTION. 209 



scending temperatures, and which constitutes a veritable 

 stellar thermometer which he can use to test the tempera- 

 ture of the stars. 



Hottest stars. 



1. Two in Argo (zeta Puppis and gamma Argus). 



2. Alnitam (epsilon Orionis). 



Stars of intermediate temperature. 



3. Achernar. 



4. Algol. 



5. Markab. 



6. ( ). 



7. Sirius. 



8. Procyon. 



9. Arcturus. 



Stars of lowest temperature. 



10. 19 Piscium. 



Considering this star table from hottest to coldest in re- 

 lation to the chemical nature of the stars comprising it the 

 evolution of matter drops into evidence. 



1. Argonian Stars. 



Predominant. Hydrogen and proto-hydrogen. 

 Fainter. Helium, unknown substance, proto-magne- 

 sium, proto-calcium, asterium. 



2. Alnitamiam Stars. 



Predominant. Hydrogen, helium, proto-silicon, unknown 



substance. 

 Fainter. Asterium, proto-hydrogen, proto-magne- 



sium, proto-calcium, oxygen, nitrogen. 



carbon. 

 14 



