Oct. 4, iQis-Mar. 27. 1916 Illustration.' 



XXV 



Flow through Weir Notches with Thin Edges and Full Contrac- 

 tions 



Page 

 Fig. I . Plan and sectional elevations of the Fort Collins hydraulic laboratory. . 1054 



2. Device used in referring elevations of the notch crest to the reading of 



the hook gauge 1056 



3. Ladder, platform, and datum rod used in calibration tanks 1058 



4. Curves showing the relation between discharges with constant heads 



through rectangular notches of different lengths and the lengths of 



the notches 1062 



5. Curve showing the relation between a in the equation Q=aL-b and the 



heads on rectangular notches 1063 



6. Curve showing tlie relation between b in the equation ^=aL — 6 and the 



heads on rectangular notches 1064 



7. Curves showing discharges tlirough rectangular notches of different 



lengths 1068 



8. Curve showing relation of coefficients (C) to lengths of rectangular 



notches lo-'i 



9. Curve showing relation of n to length of rectangular notches 1072 



10. Cur\'es showing discharges through Cipolletti weir notches of different 



lengths 1078 



11. Curve showing discharges through 2-foot rectangular and Cipolletti 



notches and 2-foot notches having i to 3 and i to 6 side slopes 1082 



12. Logaritlimic diagram of discharges through 28° 4^, 30°, 60°, 90°, and 



120° triangular notches 1084 



13. Curves showing discharges through circular weir notches 1089 



14. Curves showing effect of different end and bottom contractions upon 



discharges through i-foot and 3 -foot rectangular notches with heads of 



0.6 and I foot 1092 



15. Curves showing tlie effect of different end and bottom contractions 



upon the discharges through i-fopt and 3-foot Cipolletti weir notches 

 with heads of 0.6 and i foot 1093 



16. Curves showing the effect of different ratios of cross-sectional area of 



the weir box (.4 ) to the area of the notch (a) upon discharges through 



a i-foot rectangular notch with heads of 0.6 and i foot 1096 



17. Curves showing the side slopes required with different heads in order 



that the discharge through a 2 -foot notch will be twice the discharge 

 through a i-foot notch 1100 



18. Curves showing the discharges through a i-foot rectangular notch sub- 



merged to different depths 1103 



19. Curves showing the discharges through a 2-foot rectangular notch sub- 



merged to different depths 1 104 



20. Curves showing the discharges through a 3-foot rectangular notch 



submerged to different depths 1 104 



21. Graph showing the discharges through a 4-foot rectangular notch 



submerged to different depths 1105 



22. Curves showing the discharges through a i-foot Cipolletti notch sub- 



merged to different depths 1 106 



23. Curves showmg the discharges through a 2-foot Cipolletti notch sub- 



merged to different depths 1107 



24. Curves showing the discharges through a 3-foot Cipolletti notch sub- 



merged to different depths 1 108 



25. Curves showing the discharges through a 4-foot Cipolletti notch sub- 



merged to different depths 1109 



