COLORADO IRRIGATION WATERS AND THEIR CHANGES. 49 
in the drain waters. We have in this case an illustration in point. 
The ground waters taken three days previously showed the pres¬ 
ence of 452 and 470 grains total solids per imperial gallon; the 
above drain water showed 113.8 grains. The ground waters 
showed respectively 105 and 89 grains of sodic sulfate per gallon, 
the drain water 4.6 grains, which in proportion is very greatly 
less, the sodic sulfate amounting to one-fourth of the total in the 
case of ground water, represented by well A, and 1-24 in that of the 
drain water; the magnesic sulfate remaining relatively constant, 
one-third in the well waters and one-fifth in the drain water. The 
calcic sulfate, on the contrary constitutes 1-6 and 1-5 respectively of 
the total solids in the two well waters and 2-5 of those in the drain 
water. I unfortunately do not know even approximately the vol¬ 
ume of drainage water, but it is evident that the ratios in which 
the various salts are removed are wholly different from these in 
which they are found in the ground water. 
§ 88. The following analyses of drain waters establish and 
strengthen these statements and show that the drain waters are 
much more nearly constant in composition than the ground waters, 
and vary much less in the quantity of total solids that they 
contain. 
TABLE XL-ANALYSIS OF DRAIN WATER, JULY 23. 1900. 
Analytical 
Per 
Grs. 
Imp. 
Per 
Grs. 
Imp. 
Results 
Cent 
Gal. 
Combined. 
Cent 
Gal. 
Silicic Acid_ 
1.405 
1.030 
Calcic Sulfate _ _ 
45.265 
33.179 
Sulfuric Acid __ _ 
42.442 
31.110 
Magnesic Sulfate_ 
23.633 
17.323 
Carbonic Acid_ 
7.847 
5.752 
Potassic Sulfate.__ 
0.147 
0.108 
Chlorin . 
3.782 
2.772 
Potassic Chlorid_ 
0.055 
0.040 
Sodic Oxid_ 
14.663 
10.748 
Sodic Chlorid_ 
6.198 
4.543 
Potassic Oxid _ . 
0.115 
0.084 
Sodic Carbonate.. 
18.921 
13.869 
Calcic Oxid 
18.647 
13.668 
Sodic Silicate . . 
0.589 
0.432 
Magnesic Oxid _ 
7.876 
5.773 
Ferric and Al. Oxids 
0.040 
0.029 
Ferric and Al. Oxids 
0.040 
0.029 
Manganic Oxid ___ 
0.040 
0.029 
Manganic Oxid 
0.040 
0.029 
Ignition_ 
4.073 
2.985 
Ignition 
4.073 
2.985 
Sum 
98.961 
72.537 
Sum . 
100.930 
73.980 
Excess Silicic Acid 
1.115 
0.817 
Oxygen Eq. to Cl... 
0.852 
0.624 
Total __ _ _ 
100.076 
73.354 
Total . . 
100.078 
73.356 
Total Solids, 73.3 grains per imperial gallon. 
