42 
bulletin 82. 
§ 65. The ditch water carried total solids to the amount of 
more than twice as much as I have ever found in Poudre water at, 
or rather a little below, the point where this water was taken out. 
But I have already pointed out the fact that the Poudre water in¬ 
creases materially in the amount of total solids held in solution from 
a point just above the mouth of the North Fork to a point below 
Bellvue, a distance of less than eight miles. The maximum in¬ 
crease observed at a period of low water was about four times the 
amount contained at the higher point. It is not a matter of sur¬ 
prise then that there should be still greater increase after it has 
flowed through a cultivated section, for a little more than four 
miles. This water carried 894.5 pounds of total solids in each acre- 
foot and the salts represented were not present in the propor¬ 
tions usually found. They wer'e calcic sulfate, 393.6; magnesic 
sulfate, very little or none; sodic carbonate 239.6 and potassic oxid 
(K 2 0 ) 11.6 pounds. 
§ 66. An acre-foot of the seepage water as it was gathered 
at the time, carried 1,925 pounds of total solids, but as we do not 
know the amount of this water flowing in at the time, we cannot 
make any correction for it. The relative amount was certainly not 
as much as one-fourth and the weights of salts subsequently dealt 
with being large and only approximate at best, the seepage water 
can justly be neglected. The salts held in solution show clearly 
that it is properly classed as seepage water though evidently 
mixed with ditch water which had run over the surface of the 
meadow along the edge of which our lateral ran. These salts 
were, according to our manner of combining the analytical results, 
as follows; calcic sulfate, 828.0; magnesic sulfate, 304.0; sodic car¬ 
bonate, 511.6; potassic oxid (K 2 0 ) 12.4 pounds per acre-foot. 
§ 67. The ground water before and after irrigation carried 
the following quantities of total solids composed of the salts given 
herewith: 
TOTAL SOLIDS IN GROUND WATER AUG. 31.-SEPT. 2, 1899, 
PER ACRE-FOOT. 
Before Irrigation. After Irrigation. Pounds Gain. 
Total Solids_ 3,868.0 8,809.0 4,941.0 
Calcic Sulfate_ 1,303.5 2,942.2 1.638.7 
Magnesic Sulfate_ 893.5 2,237.5 1,344.0 
Sodic Sulfate.. 425.5 1,612.0 1,186.5 
Sodic Carbonate_ 543.0 740.0 197.0 
Sodic Chlorid_ 255.3 616.6 361.3 
Organic Matter, etc._ 447.2 660.7 213.5 
Total__3,868.0 8,809.0 4,941.0 
§ 68. This shows an increase in the total solids contained 
in each acre-foot of ground water of 4,941 pounds, but if we con- 
