This is generally well understood in common experience,
as in drying clothes rapidly by hanging them before a hot fire. At a
temperature of 100 deg F., which is often reached in portions of the
dry-farm territory during the growing season, a given volume of air
can hold more than nine times as much water vapor as at the
temperature of freezing water. This is an exceedingly important
principle in dry-farm practices, for it explains the relatively easy
possibility of storing water during the fall and winter when the
temperature is low and the moisture usually abundant, and the
greater difficulty of storing the rain that falls largely, as in the
Great Plains area, in the summer when water-dissipating forces are
very active. This law also emphasizes the truth that it is in times
of warm weather that every precaution must be taken to prevent the
evaporation of water from the soil surface.
Temperature Grains of Water held in
in Degrees F. One Cubic Foot of Air
32 2.126
40 2.862
50 4.089
60 5.756
70 7.992
80 10.
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