─────────────┬─────────────────────────────────────────────────────── Depth of │ samples. │ AREA NOT WET. ─────────────┼───────────────────────────╥─────────────────────────── „ │ First samples. ║ Second samples. ─────────────┼─────────────┬─────────────╫─────────────┬───────────── „ │ │ Pounds of ║ │ Pounds of │ Per cent of │ water per ║ Per cent of │ water per │ water. │ cubic foot. ║ water. │ cubic foot. ─────────────┼─────────────┼─────────────╫─────────────┼───────────── 0–12 inches │ 17.72│ 12.38║ 18.27│ 12.75 12–24 „ │ 19.18│ 17.05║ 19.94│ 17.72 24–36 „ │ 16.97│ 14.92║ 17.52│ 15.40 36–48 „ │ 15.49│ 14.48║ 15.16│ 14.17 ─────────────┼─────────────┼─────────────╫─────────────┼───────────── Averages │ 17.34│ 14.71║ 17.71│ 15.01 │ │ ║ │ Total amount │ │ ║ │ of water │ │ 58.83║ │ 60.04 Amount of │ │ ║ │ change │ │ ║ │ +1.21 ─────────────┴─────────────┴─────────────╨─────────────┴───────────── The above data show sufficiently well the method of investigation to be pursued in studies of this kind. =165. Capillary Movement of Water.=—The method of investigation proposed by King[114] consists in taking samples of soil at intervals of one, two, three, or four feet in depth, and determining the amount of moisture in each in connection with the amount of rain-fall during the period. The quantity of water contained in a given soil, at various depths and on different dates, is shown in the following table: Depth in Date. Per cent Pounds per Increase or decrease. feet. water. cubic foot. Pounds per cubic foot. 1 March 8th 24.33 16.98 1 April 18th 22.37 15.61 –1.37 2 March 8th 15.80 14.05 2 April 18th 21.64 19.24 +5.19 3 March 8th 11.16 9.81 3 April 18th 16.24 14.27 +4.46 4 March 8th 7.87 7.36 4 April 18th 11.19 10.46 +3.10 The rain-fall during the interval was 4.18 inches, equal to 21.77 pounds per square foot. =166. Lateral Capillary Flow.=—To determine the lateral capillary flow of water in a soil the following method, used by King[115] may be employed: