BULLETIN 82 . 
48 
a series of reactions whereby these salts pass into solution when the 
soil is supplied with an abundant quantity of water; bnt the rela¬ 
tive quantities that go into solution vary, and the ratios in which 
the salts are present are not those of their solubilities. 
THE DRAIN WATERS. 
§ 86. There was 110 drain through the plot of ground at 
the time the irrigation experiments were made, so I can not 
give analyses of drain waters which are strictly comparable to 
the waters used in irrigation. I regret this bnt I could not do 
better than to take drain water from another point, which I did. 
This plot was subsequently drained and an analysis of the water 
from this drain will be given later. The first sample of drain water 
which I shall give was taken April 20, 1900, three days later 
than the last sample of well water given, and is fairly comparable 
to these, though taken at some distance below the plot where 
the wells were dug. 
TABLE XXXIX.—ANALYSIS OF DRAIN WATER, APR. 20, 1900. 
Grs. 
Grs. 
Analytical 
Per 
Imp. 
Per 
Imp . 
Results. 
Cent. 
Gal. 
Combined. 
Cent. 
Gal. 
Silicic Acid _ 
0.8i6 
0.P63 
Calcic Sulfate _ _ . 
40.406 
45,982 
Sulfuric Acid . 
40.284 
45.843 
Magnesic Sulfate. __ 
21.260 
24.194 
Carbonic Acid ... . 
8.537 
9.715 
Potassic Sulfate_ 
0 145 
0.165 
Chlorin ...__ .. 
3.939 
4.483 
Sodic Sulfate... ... 
4.052 
4.611 
Sodic Oxid ... 
17.304 
19.692 
Sodic Chlorid ... .. 
6.500 
7 397 
Potassic Oxid 
0.079 
0.090 
Sodic Carbonate . 
20 585 
23.426 
Calcic Oxid 
16.645 
18.941 
Sodic Silicate 
0.071 
0 081 
Magnesic Oxid 
7.085 
8.063 
Ferric and Alu. Oxids 0.050 
0.057 
Ferric and Al. Oxids 
0 050 
0.057 
Manganic Oxid_ 
0 060 
0.068 
Manganic Oxid 
0.060 
0.068 
Ignition 
6379 
7.259 
Ignition 
6.379 
7.259 
Sum 
99.508 
113.240 
Sum 
101.208 
115.174 
Excess Silicic Acid 
0.811 
0.923 
Oxygen Eq. to Cl.__ 
0.887 
1.009 
Total ___ 
100.319 
114.163 
Total 
100.32 L 
114.165 
Total solids, 118.8 grains per imperial gallon. 
§ 87. This sample was taken from a new drain which was 
being laid beside an old one. The gravel at this time was full of 
water as is, so far as I know, always the ease. This is the same 
stratum of gravel mentioned in another place, also in former 
bulletins, as underlying my beet plot. A comparison of the pre¬ 
ceding analysis with one of water taken from this gravel under 
the beet plot, shows a general similarity, but with some 
differences, the most striking of which is in regard to the sodic 
sulfate, which is much more abundant in the water taken directly 
from the gravel than in the drain water. I11 this connection I 
would repeat what I have said in Bulletin No. 72, page 33, that 
the ground and drain waters are not alike; that the total solids de¬ 
crease with the depth from which the sample is taken, and that 
while sodic sulfate is abundant in the ground waters, it is not so 
