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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 im from precipitation falling on tha adjacent mountains and perca- lating into tha sands and gravels, the precipitation falls in tha fare of rains and snow, largely snow, and recharge occurs — the major portion of it— in tha spring of the year as the snow melts. It moves down the side of the mountainstreams which disappear as the water percolates into the ground. Wells drilled to this sand and gravel aquifers encounter water. In sene of them the water Is not under artesian pressure. In others, It is under artesian pressure, and the pressure is suffi­cient to esuse the water to flow to the land surface, giving what is commonly known as a free-flowing well, When the sand or gravel deposits are beneath what we term relatively impermeable deposits, which arc composed of clay oar silt, it forms a capping there which confines the water beneath that confining bed, and a pressure is exerted upward, and this pressure is what causes the wells to flow when the well Is drilled, penetrating the sand and gravel beneath the confining bed. ?he aquifers have been called, for the purpose of describing them, the near-surface water,which is the water encountered in shallow wells close to the surface* the upper tone of aquifers which In the vicinity of Las Vegas Is *>00 feet — the middle suae, which is around TOO feet, and then another sons at a greater depth, from which there is rela­tively small production* Q. Have you made any study as to the rate of recharge and withdrawals of water from this Las Vegas Basin? A, 1«$| in the course of the investigations of the Las