Mar. i, 1924 
Movement of Water in Irrigated Soils 
673 
the diagram, which shows a cross section of the ground in line with the 
wells, the position of the free water in each well is shown in relation 
to the land surface. The proportion of the dissolved solids, or salt 
content, of the water of each well is shown in figures below each well and 
shown also diagrammatically in the circles. It is apparent that the 
quality of this underground water is very different in the different wells. 
In the well at the extreme right, which is close to the canal, the salt 
content is very low. The next three wells show more salty water, while 
the wells on either side of the coulee are again less salty. The details of 
the analyses of the samples from these wells are shown in Table XXIV. 
Table XXIV .—Quality of underground water on the Shoshone project, Wyoming, from 
a series of shallow wells 250 feet apart; collected by Iakish and analyzed by Breazeale 
Total 
Constituents as percentage of total solids. 
Total 
acids. 
Well No. 
solids, per 
cent. 
£a+Mg. 
HCO., 
2 
Cl. 
SO*. 
no 8 . 
11. 
6. 031 
• 4-9 
1. 1 
2.8 
58. 0 
5 -1 
67. 0 
12. 
• 572 
15-9 
3-3 
2. O 
63. 0 
„ * 9 
69. 2 
13 . 
14 . 
• 454 
4. 948 
19 - 5 
12. 5 
9.8 
1. 1 
3-4 
2.9 
52. 5 
62. 0 
Tr. 
65- 7 
66. 0 
15 . 
2. 452 
24. 8 
•9 
1.4 
64. 0 
66. 3 
16 . 
17 . 
6. 452 
. 106 
12. 1 
16. 0 
•4 
22. 0 
i- 4 
Tr. 
63. 0 
49. 0 
64. 8 
71. 0 
The results given in Table XXIV tend to confirm the implication of the 
conditions shown in the figure, which is that the underground water is not 
moving; at least it is not moving in the direction of its gradient. The 
samples taken from these wells differ profoundly not only as to quantity 
of dissolved material but also as to its character. Such differences could 
not exist if there were much movement of the water with its consequent 
mixing. 
The condition of stagnant underground water such as that just described 
might be regarded as not unusual when as in this case the land was not 
irrigated. The frequent application of irrigation water might be expected 
to result in time in obliterating such differences. The results of another 
series of observations made in an irrigated field on the Newlands Experi¬ 
ment Farm, Nev., show that even where a field is irrigated frequently 
and copiously and where there is a drainage system to carry away the 
surplus underground water the movement of the water is very irregular 
and its quality is equally variable, at least for a long time. The observa¬ 
tions now to be presented were made in connection with the leaching 
experiment referred to in the preceding pages. The field included 6 acres 
divided into 12 plats, each 85 feet wide. These plats have been irrigated 
almost continuously since 1908, but much of the soil has been imper¬ 
meable and crop growth has been very irregular. A view of the crop 
growth on one of the plats in this field is shown in Plate 2, A. In 1913 the 
accumulation of water in the subsoil of this field had reached such a point 
that drainage became essential and a tile drain was laid along the south 
side of the field about 5 feet below the surface. Notwithstanding per¬ 
sistent efforts to improve the condition of the soil by careful irrigation 
and good tillage, accompanied by manuring and the use of gypsum, this 
