VI LETTER TO THE GOVERNOR. 



grateful acknowledgments to the many good and true friends of the 

 Survey in various portions of the State, through whose influence and 

 encouragement the work has been brought so near to a final completion, 

 and more especially to those eminent eastern scientists, Prof. Henry, of 

 the Smithsonian Institution, Prof. Dana, of New Haven, and the 

 lamented Agassiz, for the loan of rare scientific books from the exten- 

 sive libraries under their control, and for their personal influence and 

 assistance freely manifested in various ways, by which the best interests 

 of the Survey have been greatly promoted. 

 I have the honor to be 



Your obedient servant, 



A. H. WOBTHESr. 

 Springfield, III., Sept., 1S75. 



