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This seepage water is from Larimer county, and the 
different conditions of soil and the different waters used for 
irrigation influence the character of the salts taken into 
solution or left by evaporation and consequent concentra- 
lon. 1 he writer does not know the history of the land 
from which this drain water was taken; but there is no 
doubt that it is a seepage water which had collected in the 
°Vf r portions of the farms and was drawn off by the laying 
of this drain The water used for irrigating was taken from 
the Lache-a-la-Poudre river. The water supply for the city 
ot cort Collins is taken from the same source, and as de¬ 
livered for domestic use contains in the month of Febru¬ 
ary, when the water is low, rather less than ten grains of 
solid matter to the gallon. This gives us a general, though 
somewhat indefinite, idea of the amount of salts due to coll- 
■ centration and solution from the soil. 
Fhe Arkansas river water may contain more solids 
when taken out for irrigating purposes, but there is little 
doubt that the magnesic salts, in both cases, are taken into 
solution as the result of chemical changes between the salts 
ot the soil and those taken into solution by the water The 
ground vvater is not so different from the seepage water, 
but that it may be considered as a product of the concen¬ 
tration of seepage waters. This is not the place to discuss 
the manner in which this concentration has been effected 
We have intimated an answer to the most patent inquiry, i. 
e., whence the magnesic salts contained in both the sam¬ 
ples, the ground as well as the seepage waters, especiallv as 
the irrigating water used is river water, supplied by melting- 
snows and flowing for the greater part of its course over 
gneiss ic or granitic rocks. This is more literally true of ir¬ 
rigation water used in parts of this county (Larimer) than 
it is of that used in Otero county, which is farther removed 
from the mountains. The analyses of drain waters taken 
m Luropean soils are not closely comparable with our seep¬ 
age \vaters, for these soils have been washed out and ours, 
m this semi-arid climate, have not been; still even the 
Luropean drain waters show a relatively large amount of 
magnesic carbonate present in them ranging from one-third 
to one-twelfth of the total lime salts. 
This subject may form the basis of some future work by 
the department, though the subject has already been ap¬ 
proached in Bulletin No. 9, of this Station. 
T. he relation of soil water to the salts taken up by 
plants is apparently not the same as that sustained by solu¬ 
tions in water culture. Our alfalfa roots have not taken it 
up from this depth. We have given analyses of the soils 
