I74 NEW YORK STATE MUSEUM 



accurately measured and there is no way of guarding against repe- 

 tition of folds. The valley floor is decidedly terraced at an ele- 

 vation of about 130 A.T. One side is limestone and the other is 

 granitic rock. This is probably a local mark of the Tertiary base 

 leveling work. 



Because of the great depth of this narrow gorge, it would require 

 a 500 foot shaft at each side to lead from hydraulic grade down to 

 a safe level for the pressure tunnel. For a crossing not more than 

 2000 feet long this is excessive and the cost becomes greater than 

 by other methods of construction. Consequently the tunnel plan 

 has been abandoned and it is not likely that further data bearing 

 upon these questions will be added. 



