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NEW YORK STATE MUSEUM 



Huntingtonville dam. Two or more readings of the gage are 

 taken daily and a mean taken. In computing the flow an allow- 

 ance of 200 cubic feet per second has been made for leakage 

 through seams and crevices in the rock underlying the dam. 

 This amount is somewhat general, as it has only been arrived 

 at from an estimate of the size of the openings from the state- 

 ment of eye witnesses when the water was drawn down in the 

 summer of 1897. The following cut shows a section of the 

 Huntingtonville dam on Black river: 



Fig. 25 Section of dam on Black river. 



Geologically, Black river lies in the horizon of the Trenton 

 limestone, with its tributaries rising into the unclassified 

 granites and gneisses of the Adirondack region. 



Discharge measurements of Lake Ghamplain. Lake Champlain 

 drains an area of 7960 square miles, which is subdivided as fol- 

 lows: 



Square miles. 



Area in Quebec 740 



Area in Vermont 4.270 



Area in New York 2,95Q 



Area of water surface of lake 400 



Total 8,360 



