Farm drainage / The Principles, Processes, and Effects of Draining Land with Stones, Wood, Plows, and Open Ditches, and Especially with Tiles

by Henry F. French

Fig. 95.

Fig. 96.

Section of land before it is drained.

Section of land after it is drained.

"In the first figure, 1 represents the surface soil, through which evaporation takes place, using up the heat which might otherwise go to the roots of plants; 2, represents the water table, or surface of stagnant water below which roots seldom go; 3, water of evaporation; 4, water of capillary attraction; 5, water of drainage, or stagnant water.

"In the second figure, 1 represents the surface-soil warmed by the sun and Summer rains; 2, the water-table nearly four feet below the surface—roots of the wheat plant have been traced to a depth of more than four feet in a free mold; 3, water of capillary attraction; 4, water of drainage, or stagnant water."

CHAPTER XV
TEMPERATURE AS AFFECTED BY DRAINAGE.

Drainage Warms the Soil in Spring.—Heat cannot go down in Wet Land.—Drainage causes greater Deposit of Dew in Summer.—Dew warms Plants in Night, Cools them in the Morning Sun.—Drainage varies Temperature by Lessening Evaporation.—What is Evaporation.—How it produces Cold.—Drained Land Freezes Deepest, but Thaws Soonest, and the Reasons.