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N E \Y YORK STATE MUSEUM 



Since the principal canal to be constructed in connecting the 

 Great Lakes with the Atlantic tidewaters passes through the 

 State of Xew York, the following outline of the work of the 

 Board of Engineers is herewith given: 



Dimensions of prism. This board made a study of the dimensions 

 of St Clair. Suez. Manchester, Amsterdam and Kiel canals, to- 

 gether with the speed which steamships can maintain in these 

 waterways, arriving at the conclusion that the cross-section of 

 the canal prism should be made such as to permit a speed of 

 8 miles per hour on tangents without danger to either passing 

 ships or damage to the banks. On this basis the cross-section 



Fig. 59 Rock cross-section of deep waterways for 30-foot channel. 



best adapted for economic transportation of the lake traffic and 

 permitting a speed of 8 miles per hour is about 5500 square 

 feet for a 21-foot waterway and 8000 square feet for a 30-foot 

 waterway. 



On open rivers a bottom width of 600 feet was adopted as 

 necessary for safe navigation. On the Hudson and Mohawk 

 rivers the cross-section of the waterway was designed with 

 reference to carrying flood discharges with current velocities not 

 exceeding 4 linear feet per second. On the Mohawk river the 

 economic cross-section for carrying the flood discharge at not 

 exceeding 4 linear feet per second required a deptji of consider- 

 ably ever 21 feel . 



Dimensions of structures. The dimensions of lock structures 

 were designed with reference to the type carrier likely to use the 

 waterway and to the importance of the amount of time required 

 to pass a ship through the waterway relative to the number of 

 ships which can be passed through a lock in a given time, and in 



