208 LECTUEE ON THE HEAVENLY BODIES. 



CONCLUSION. 



In conclusion, llie new knowledge that has been gained from these observa- 

 tions witli the prism may be summed up as follows : 



1. All the brighter stars, at least, have a structure analogous to that of the 

 sun. 



2. The stars contain material elements common to the sun and earth. 



3. The colors of the stars have their origin in the chemical constitution of 

 the atmospheres which surround, them. 



4. The changes in brightness of some of the variable stars are attended with 

 chauge| in the lines of absorption of their spectra. 



5. The phenomena of the star in Corona appear to show that in this object, 

 at least, great physical changes, are iu operation. 



6. There exist in the heavens true nebula. These objects consist of lumin- 

 ous gas. 



7. The material of comets is very similar to the matter of the gaseous nebulae, 

 and may be identical with it. 



8. The bright points of the star-clusters may not be in all cases stars of the 

 same order as the separate bright stars. 



It may be asked what cosmical theory of the origin and relations of the heav- 

 enly bodies do these new facts suggest? It would be easy to speculate, but it 

 appears to me that it would not be philosophical to dogmatize at present on a 

 subject of which we know so very little. Our views of the universe are under- 

 going important changes ; let us wait for more facts, with minds unfettered by 

 any dogmatic theory, and therefore free to receive the obvious teaching, what- 

 ever it may be, of new observations. 



Star differs from star in glory, each nebula and. each cluster has its own special 

 features ; doubtless in wisdom, and for high and important purposes, the Creator 

 has made them all. 



