. Elementary lessons in the physics of agriculture . Showing the relation of the water-table to the surface on Picnic Point. Vertical scale, for the water-table 1 in. =4 ft., for the surface, 1 in. =8 ft. the water stands highest under the highest ground, which ap- pears to act simply as a reservoir in which the rains accumu- late, the fi'iction of the soil retarding the flow toward the lake. The common belief that wells are supplied with water from adjoining lakes or rivers, the water simply Altering through the soil into them, is not generally true though it may be in some exceptional cases.
. Elementary lessons in the physics of agriculture . Showing the relation of the water-table to the surface on Picnic Point. Vertical scale, for the water-table 1 in. =4 ft., for the surface, 1 in. =8 ft. the water stands highest under the highest ground, which ap- pears to act simply as a reservoir in which the rains accumu- late, the fi'iction of the soil retarding the flow toward the lake. The common belief that wells are supplied with water from adjoining lakes or rivers, the water simply Altering through the soil into them, is not generally true though it may be in some exceptional cases. Neither is it usually necessary to dig to a depth of the level of adjoining lakes before water is found. Here at Madison water is obtained in wells, in some cases, 20 feet above the level of the lakes, and the wells may" not be more than 40 rods from the lake shore and sunk simply in a ridge of glacial sand and gravel lying between the two lakes. 159. Fluctuations in the Level of the Water-Table. The level of the water in the ground is not constant, but stands higher after a series of wet years and faUs again with a suc- cession of dry seasons. There is also an annual rise and faU of the water-table, the water standing lowest toAvard the lat- ter part of fall or early winter and highest in the spring. In those cases where the water-table lies near the surface it is frequently raised by single heavy rains. Even changes in at-
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Keywords: ., bookcentury1800, bookdecade1890, bookpublishermadis, bookyear1894
