Journal of Agricultural Research 



Table II. — Comparisons of variations in percentage of discharge by two-point, single- 

 point, and integration methods from discharge by multiple-point methods for different 

 velocities, depths, and values of n 



COMPARISONS FOR DIFFERENT VELOCITIES 



COMPARISONS FOR DIFFERENT DEPTHS 



Mean depth of canal 

 section in feet: 

 Less than i.oo. . . . 



I.oo to 1.50 



1.50 to 2.00 



2.00 to 2.50 



2.50 to 3.00 



Over 3.00 



Mean 



96 



— o. 6s 



+ .21 

 + 1- 32 

 -f I. 29 

 4- .97 

 + 1.09 



+ -73 



2. 06 



1.23 



1-73 

 1.58 

 1.25 

 I. 19 



I- 51 



95 



3.66 

 I. 90 

 2.51 

 2.82 



1-95 



2.44 



2.54 



+ 1. 

 + 1.46 

 + .86 

 + 1.08 



- .60 



- .26 



55 + • 76 



2.65 

 1.65 

 1.49 

 2.81 



I. 84 

 ^■Z3 



2. 07 



COMPARISONS FOR DIFFERENT VALUES OF n 



The two-point method appears to give results equally accurate for all 

 velocities, depths, and values of n, the variations which occur not being 

 seemingly dependent on any of these three factors. The probable error 

 of a single observation is generally less for the large velocities and 



