CONTENTS xiii 
Extent of Roots . 2 a: oh ° ‘ . . - 84 
Depth of Root Penetration. . . . : . . - 86 
CHAPTER VII 
Storing Water In THE SOIL. . . a . ‘ 94-129 
Alway’s Demonstration 1% @ we «© ww » 5 
What becomes of the Rainfall? . ‘ : : . - 
The Run-off . F ‘ 5 . si . . ‘ - 98 
The Structure of Soils . < : : - : és - 99 
Pore-space of Soils . . ‘ ° . ‘ ° - 101 
Hygroscopic Soil-water . . . c . . . - 102 
Gravitational Water. i P i . . . » 104 
Capillary Soil-water . ‘ " x . 106 
Field Capacity of Soils for Capillary Water . . - . 107 
Downward Movement of Soil-moisture . i ‘ ‘ » lil 
Importance of a Moist Subsoil 2 . a . . 116 
To what extent is the Rainfall stored in : Soils ae - . 119 
The Fallow . ‘ : F . ; . 122 
Deep Plowing for Water Store é 7 ‘ . 7 . 125 
Fall Plowing for Water Storage . F . ‘< . - 126 
CHAPTER VIII 
REGULATING THE EVAPORATION . 3 = ‘ qj - 130-164 
The Formation of Water Vapor . z . 7 4 . 182 
Conditions of Evaporation from Soils . é ‘ ‘ . 136 
Loss by Evaporation chiefly at the Surface . i. . . 19 
How Soil-water reaches the Surface . - ‘ : . 141 
The Effect of Rapid Top-drying of Soils c ‘ : . 147 
The Effect of Shading . . ‘ F s : . . 150 
The Effect of Tillage . : . . . . . . 152 
Depth of Cultivation . . - . , < : . 157 
When to Cultivate or Till . ‘ : sj - - - 158 
