TO 



THE REV. ADAM SEDGWICK, 



F.R. & G.S. 



PRESIDENT OF THE BRITISH ASSOCIATION FOR 

 THE ADVANCEMENT OF SCIENCE, 



&c. &c. &c. 



AS A MARK OF 

 HIS GREAT ADMIRATION AND SINCERE ESTEEM, 



THIS WORK 



IS RESPECTFULLY DEDICATED, 



THE AUTHOR. 



690908 



