Office of the United States Geological 



Exploration of the Fortieth Parallel, ' 

 23 Fifth Avenue, New York, January, 1877. 



General: I have the honor herewith to transmit Volume II of the 

 Report of this Exploration. It presents the Descriptive Geology of the 

 Fortieth Parallel area, and is by S. F. Emmons and Arnold Hague. 



The scientific earnestness of their long labor will inevitably be read 

 between the lines of their geology. Now that they lay down their hammers, 

 it only remains for me to bear hearty tribute to the vigor and persistence 

 which have characterized their ten years of investigation. 

 Very respectfully, your obedient servant, 



CLARENCE KING, 



Geologist-in- Charge. 

 Brigadier-General A. A. Humphreys, 



Chief of Engineers, U. S. Army. 



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