334 



NEW YORK STATE MUSEUM 



H= bead-on h = head-on 

 weir, in feet dam, in feet 



Computed discharge Computed discharge 

 over weir, in cubic over dam, in cubic 

 feet per second, for feet per second, for 

 heads — H heads — h 



Percentage.dif- 

 f erenlce, in 

 discharges 



(1) 



(2) 



(3) 



(5) 



0.50 

 0.70 

 0.80 

 1.02 

 1.86 

 2.01 

 2.42 

 2.65 

 3.20 

 3.78 

 4.37 

 4.65f 



0.60 

 0.83 

 0.90 

 1.00 

 1.55 

 1.75 

 2.00 

 2.50 

 2.75 

 3.00 

 3.25 

 3.35f 



1 325 

 1 490 



1 965 



2 250 



2 990 



3 840 



4 770 



5 240 



185 

 310 



450 

 540 



1 260 



1 605 



2 100 



3 230 



3 860 



4 554 



5 280 

 5 590 



135 

 330 



445 

 505 



—37.0 

 + 6.0 



— 1.0 



— 7.0 



— 5.0 

 +10.0 

 + 7.0 

 +44.0 

 +29.0 

 +19.0 

 +11.0 

 + 7.0 



In order to correlate the measurements at the Hydraulic Power 

 Company's dam with those at the weir, observations were taken 

 at each place as nearly cotemporaneously as they could be made 

 by a man going immediately from one to the other. The fore- 

 going tabulation gives some of the heads actually observed at the 

 weir and dam, together with the discharge over the weir in com- 

 parison with the computed discharge over the dam, and the per- 

 centage difference. 



The crest of the Mount Morris dam was quite irregular, and in 

 order to apply weir formulas an accurate profile was taken and 

 the crest subdivided into a number of approximately level sec- 

 tions with each section computed separately, advancing by 0.1 foot 

 up to 10 feet. The flow over the entire dam was obtained by 

 adding together the sums of the several sections at the corres- 

 ponding bights and tabulating them. A gage graduated to 0.05 

 foot was erected on the river bridge a short distance away, with 

 its zero level coinciding with the lowest point of the dam. During 

 ordinary stages of the river, readings of this gage were taken 

 twice each day, but in time of high water, in order to obtain the 

 movement of floods as accurately as possible, readings were taken 

 several times a day. In order to compute the flow readily a 

 curve was projected from which, w ith the given gage liiglus, the 

 flows in cubic feet per second could be read off. 



t Approximate; taken f roin curve. 



