Education Department Bulletin 



Published fortnightly by the University of the State of New York 



Entered as second-class matter June 24, 1908, at the Post Office at Albany, N. Y., 

 under the act of July 16, 1894 



No. 489 ALBANY, N. Y. February 15, 1911 



New York State Museum 



John M. Clarke, Director 

 Museum Bulletin 146 



GEOLOGY OF THE NEW YORK CITY (CATSKILL) 



AQUEDUCT 



STUDIES IN APPLIED GEOLOGY COVERING PROBLEMS ENCOUNTERED IN 

 EXPLORATIONS ALONG THE LINE OF THE AQUEDUCT FROM THE 

 CATSKILL MOUNTAINS TO NEW YORK CITY 



BY 



CHARLES P. BERKEY 



INTRODUCTION AND ACKNOWLEDGMENT 



It is the writer's hope that the series of studies brought together 

 in this bulletin may help to effect a wider appreciation of the prac- 

 tical usefulness of geology. The volume contains a summary of 

 the local geologic facts and the general principles found helpful in 

 solving some of the problems encountered in a single great engineer- 

 ing enterprise. The summary is accompanied by brief discussions 

 of the methods employed and of the final results or conclusions 

 reached. It is therefore essentially a study in applied geology. 



Seldom has so favorable an opportunity been afforded to follow 

 extensive exploratory work and check geologic hypothesis or theory 

 by subsequent proof. And still more seldom have engineers in 

 charge of similar works so fully appreciated the value of geologic 

 investigations and the extent to which they can be utilized as a 

 guide. 



More credit is due to Mr J. Waldo Smith, chief engineer of the 

 Board of Water Supply of the City of New York, than to any one 

 else for appreciating the importance of the geologic complexity of 



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