14 
BULLETIN 1067, U. 
DEPARTMENT OF AGRICULTURE. 
into the water. By way of comparison, in the test made at Gueydan, 
La., at the pumping plant of Subdistriet Xo. 1. Gueydan drainage 
district, the loss of head corresponding to those given above amounted 
to 0.3 foot. 
SECOND TEST. 
A second test was made to determine the efficiency of engine, 
pump, and piping. This test was of special interest, inasmuch as 
changes had been made in the suction and discharge pipes of two 
pumps since the previous test of October 19, 1912. The intake ends 
of the suction pipes and the exit ends of the discharge pipes as origi- 
nally constructed were very poorly designed. Since the first test 
was made the pipes had been replaced by others with well-designed 
ends. The side clearance of the open impeller of the 36-inch pump, 
which had been nearly three-fourths inch, had been reduced to about 
one-eighth inch, and the impeller blades in both pumps had been 
lengthened. 
The changes were beneficial to plant efficiency, although it is diffi- 
cult to say how much each contributed to the improved conditions. 
Lengthening the impeller blades and decreasing the clearance gave 
more water for a given lift and number of revolutions, while the 
elimination of entrance and discharge losses decreased the total head 
on pump. The second test was run at a greater lift than was the 
first, and this also contributed to the higher efficiency. The results 
of the test are given in Table 6, and a comparison made with the 
first test in Table 7. 
Table 6. — Second test of Phillips Land Co. pumping plant. Aug. 11. 1916. 
36-IXCH UNIT. 
Time. 
Speed. 
Indi- 
cated 
horse- 
power. 
Actual 
lift. 
Discharge. 
Useful 
water 
horse- 
power. 
Efficiency 
of * 
engine, 
pump, 
and 
piping. 
11.15.. 
F.p.m. 
146 
146 
146 
146 
146 
138 
137 
136 
135 
141 
154 
153 
154 
153 
160 
160 
160 
81.20 
81-25 
78.80 
78.60 
80. 30 
67.20 
65. 72 
62.95 
61.70 
71.65 
93. 15 
89.10 
91.60 
91.35 
103. 25 
102. 50 
101.90 
Feet. 
5.90 
5.95 
6.00 
6.05 
6.10 
6.12 
6.14 | 
6.16 
6.18 
6.13 
6.20 
6.23 
6.25 
6.29 
6.35 
6.38 
6.42 
Sec.-ft. 
64.21 
63.00 
61.40 
62.13 
62. 75 
48.53 
47.18 
43.76 
43. OS 
59.20 
69.06 
69.03 
69.21 
68. 62 
74.48 
74.00 
74. fN 
G.p. m. 
28.800 
28.300 
27.600 
27.9)0 
28.200 
21,800 
21.200 
19,650 
19. 350 
26.600 
31.050 
31,000 
31.100 
30.800 
33. 400 
33. 250 
33. 300 
42.90 
42.50 
41.70 
42.50 
43.30 
33.65 
32.75 
30.55 
30.20 
41.10 
48.50 
48.70 
49.00 
48.90 
53. 60 
53.50 
53. 80 
Per cent. 
52.9 
11.20 
52.4 
11.25 
53.0 
11.30 
54.1 
11.35.. . 
53.9 
11.40 
50.2 
11.45.. 
49.8 
11.50 
48.6 
11.5.") 
48.8 
12.35 
57.3 
12.45 
52.0 
12.50 
54.7 
12.55 
53.5 
1.00 
53.5 
1.05 
51.8 
1.10 
52.2 
1.15 
52.9 
Mean 
148 
76.6 
6.17 
61.98 
27.^17 
43. 36 
52.45 
