THIS 



COURSE OF NATURE 



A.3ST .ADDRESS 



DELIVERED BEFORE THE 



AMEEICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE, 

 St, Louis, August 22, 1878, 



BY 



SIMON NEWCOMB, 



M 



Retiring President of the Association. 



SALEM: 

 PRINTED AT THE SALEM PRESS. 



1878. 



