-4 The Colorado Experiment Station 
samples would have been taken from Hole No. i, because the pre¬ 
ceding sample of water was taken from this hole, but under the 
conditions I would have had to dig another hole to do so, and as 
number 4 was only 50 to 60 feet north of it,I took this instead. 
It would have been better to have taken the sample at the first 
place instead of at the second, for a few feet, say 50, as in this case, 
may make too much difference in the composition of the ground- 
waters to permit of their comparison. This fact is shown by wells 
one and two given on page 8. These wells were sunk to 
different depths, but both entered the ground-water. Though these 
wells were only about twelve feet apart and the corresponding 
samples were taken on the same dates, the waters are scarcely com¬ 
parable in any respect. The value of three isolated samples of 
water is but small in representing the underground conditions in 
an acre of land, especially as only two of them were taken on the 
same date. The study of ground-waters presents more difficulties 
than any subject that I know of and to interpret the results obtained 
is a very unsatisfactory task. We will give the analyses of these 
ground-waters for just what they may be worth. We do this, in 
fact we hold it as indispensable to give them, in order to complete 
our data regarding this land. This water was met with at dif¬ 
ferent depths from the surface. I assumed that this land was so 
open and uniform in structure that the water-plane at least would 
be the same when the holes were dug in level land and only about 
50 feet apart. I am not sure that this was true, still in spite of our 
doubts, we may assume it to have been so. The difference in the 
water-planes found in December and May was one foot and seven 
inches. The analytical results were as follows: 
ANALYSES OF GROUND WATERS. 
Depth of water-plane 
Hole No. 1. 
4 / Qrt 
Hole No. 4. 
4' 2 " 
Hole No. 6. 
8 ' 7 " 
Water-residue 
Percent. 
Water-residue 
Percent. 
Water-residue 
Percent. 
Calcic Sulfate . . 
Magnesic sulfate 
Magnesic chlorid 
Potassic sulfate 
Potassic chlorid 
Sodic sulfate . . 
Sodic carbonate 
Sodic chlorid . . . 
Sodic nitrate . . 
Manganic oxid. . 
Sodic silicate . . 
20.286 
10.174 
20.593 
41.753 
40.947 
32.658 
7.169 
4.027 
3.484 
3.120 
5.042 
11.625 
14.763 
8.670 
7.129 
13.010 
13.305 
11.495 
0.164 
0.226 
11.343 
17.528 
0.729 
0.479 
0.398 
100.000 100.000 
Total 
100.000 
