. Proceedings of the American Society of Agronomy . MCCALL AND BOWER FIELD STUDY OF SOIL MOISTURE. 75 were then cut free (PL II, Fig. i) and a case of heavy galvanizediron (PI. I, Fig. 2) slipped down over the block until it rested onthe galvanized iron plate at the bottom. The watertight joint be-tween the casing and the bottom was secured by a crimped and sol-dered joint. By this means blocks of soil were securely cut off fromall contact with the surrounding soil. Before the trenches werefilled a stand pipe was erected on the outside (PI. II, Fig. 2), butconnected with the interior near the
. Proceedings of the American Society of Agronomy . MCCALL AND BOWER FIELD STUDY OF SOIL MOISTURE. 75 were then cut free (PL II, Fig. i) and a case of heavy galvanizediron (PI. I, Fig. 2) slipped down over the block until it rested onthe galvanized iron plate at the bottom. The watertight joint be-tween the casing and the bottom was secured by a crimped and sol-dered joint. By this means blocks of soil were securely cut off fromall contact with the surrounding soil. Before the trenches werefilled a stand pipe was erected on the outside (PI. II, Fig. 2), butconnected with the interior near the bottom, the opening into the tankbeing protected by means of a fine wire screen. The purpose of thisstandpipe was to enable us to maintain the water table at any desiredlevel within the tank. The siphon tank with an outlet tube extendingdown into the standpipe has enabled us to maintain our water tableat a given height automatically and at the same time measure theamount of water used during given intervals. Plates I and II show the construction o
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