The Colorado Statute Inch 
i5 
TABLE 5. 
RESULTS OF 
EXPERIMENTS 
WITH AZUSA 
HYDRANT. 
Discharge 
Actual Area Actual 
in Miner’s 
Intended 
Opening 
of Opening 
Discharge in 
Inches 
Discharge 
Percent* 
in Square 
Cubic Feet 
Corrected for 
in Miner’s 
of 
Inches 
per Second 
Nominal Area 
Inches 
Error 
A . 
9.991 
.195 
9.8 
10 
2.0 
B . 
. 14.488 
.281 
14.1 
15 
6.4 
C . 
. 24.494 
.474 
23.7 
25 
5.5 
D . 
. 49.008 
.967 
48.4 
'50 
3.3 
A+B . 
. 24.479 
.478 
23.9 
25 
4.6 
A+B + C . 
.. 48.973 
.959 
48.0 
50 
4.2 
A+B+C+D . 
. 97.981 
1.925 
96.3 
100 
3.8 
A+B+D _ 
. 73.487 
1.439 
72.0 
75 
4.2 
A+C . 
. 34.485 
.668 
33.4 
35 
4.8 
A+C+D _ 
. 83.493 
1.641 
82.1 
85 
3.5 
A+D . 
. 58.999 
1.157 
57.9 
60 
3.6 
B+C . 
. 38.982 
.762 
38.1 
40 
5.0 
B+C+D _ 
. 87.990 
1.729 
86.5 
90 
4.1 
B + D . 
. 63.496 
1.248 
62.4 
65 
4.2 
C + D . 
. 73.502 
1.451 
72.6 
75 
3.3 
* Percent 
of Error between intended 
discharge and 
correct discharge in 
Miners’ inches, using the 
correct discharge as the basis. 
The Miners’ 
Inch was 
taken as 1-50 
cubic foot 
per second, which is Southern 
California practice. 
TABLE 6. 
WIDTH OF OPENINGS TO GIVE THE INTENDED DISCHARGE WITH 
AZUSA HYDRANT. 
Depth Width Discharge 
Opening in in in Miner's 
Inches Inches Inches* 
A . 4 2 9-16 10 
B. 4 3 % 15 
C . 4 6 15-32 25 
D . 4 12 % 50 
* Southern California inch, which is 1-50 cu. ft. per sec. 
SUMMARY. 
The value of the Colorado Statute Inch has been assumed to be 1 /3S.4 
part of a cubic foot per second, and this figure has been commonly used 
for years. It is not a legal definition of the Statute Inch and may be in 
error as shown in tables 1, 2 and 3. The number of Statute Inches to the 
second foot may vary from at least 33.7 to 42.9 and still conform to the 
law in every particular. Although the use of the Statute Inch is some¬ 
what limited at the present time, it is used in connection with interpret¬ 
ing water rights, and it would be well to have its value fixed by law as 
a definite part of a second foot. 
The discharges obtained in these experiments are probably less than 
would be obtained in actual practice where one or more of the following 
conditions are usually found, and they all tend to increase the flow 
through an orifice: thick edges, such as an opening cut in a plank with¬ 
out outward bevel to the edges; rounding edges; velocity of approach 
which would be caused by an orifice placed in a small box, or an accumu¬ 
lation of sand which would reduce the distance from the bottom of the 
% 
/ 
