Chapter XI

THE WATER OF SOILS. HYGROSCOPIC AND CAPILLARY MOISTURE,
188.—General Properties, 188.—Physical Factors
of Water compared with other Substances. Table,
188.—Capillarity or Surface Tension, 189.—Heat Relations,
190.—Density, 190.—Specific Heat and its Effects,
190. Ice, 191.—Vaporization, 191.—Solvent Power,
191.—Water-requirements of Growing Plants, 192.—Evaporation
from Plants in Different Climates, 192.—Relations between
Evaporation and Plant Growth. Table, 193.—Fortier’s
Experiments. Figure, 194.—Different Conditions of
Soil Water, 196.—_Hygroscopic Water in Soils; Table_,
196.—Influence of Temperature and Air-Saturation,
197.—Utility of Hygroscopic Water to Plant Growth,
199.—Mayer’s Experiments, 200.—Summary, 200.—_Capillary
Water_, 201.—Ascent of Water in Soil-Columns. Table,
202.—Ascent in Uniform Sediments. Figure, 204.—Maximum and
Minimum Water-holding Power, 207.—Capillary Water held at
different Heights in a Soil Column. Table, 208.—Capillary
Action in Moist Soils, 210.—Proportion of Soil Moisture
Available to Plants, 211.—Moisture Requirements of Crops in
the Arid Region, 211.—Tables of Observations in California,
214.