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moisture during a portion of the year, particularly at times of summer drought. Operations on a considerable scale have not been attempted, but many small gardens are being watered. Nearly all of this land requires drainage, and this is especially the case when irrigation is introduced. The prairie land in this region is not notably rich, but it is easily worked, and as a rule ground water is near the surface.

The source of water for the city of Galveston is at the suburban town of Alta Loma, 18 miles distant from Galveston. Here are 27 wells 7 inches in diameter and 3 wells 9 inches in diameter, from 750 to 850 feet deep, all located in a direct north-south line, 300 to 750 feet apart, making a total distance from end to end of 16,350 feet. The wells, at 2 feet above the ground, showed a static pressure of from 5 to 7 pounds per square inch. Water is derived from several horizons, and the combined flow is 12 million gallons per day, or 18.60 second-feet. The pressure is sufficient to deliver 5 million gallons daily, or 7.73 second-feet, at the city of Galveston, 18 miles away, through a 30-inch pipe having a fall of 1 foot to the mile. A portion of this 30-inch pipe is depressed about 10 feet for a distance of 2½ miles, from the mainland to the island, under West Galveston Bay. These wells have been flowing for three years. The cost for the installation of the entire plant was $790,000. Analysis shows that the water is usually pure, and the people of Galveston are highly gratified in having a water supply of such excellence.

The water- bearing strata underlying this portion of Texas are so uniform in character that contractors do not hesitate to guarantee a flow of from 25,000 to 50,000 gallons daily, or 0.04 to 0.08 second-feet, for a specified size of well at any point in or near Galveston County. There are 5 artesian wells at and about Clear Creek, 1 at Shell Siding, 10 in the vicinity of Dickinson, 2 at North Galveston, 1 at Texas City, several at Hitchcock, 2 or 3 at Alta Loma in addition to those already mentioned, and 2 at Arcadia, making a total of not fewer than 55 for the county. In some localities sufficient flow for smaller wells is obtained at a depth of 490 feet, though occasionally the extreme depth of from 1,000 to 1,100 feet is required.

Water for irrigation is also provided by using windmills. There is a stratum of water-bearing sand at a depth of from 30 to 60 feet which furnishes an abundant supply for irrigation by the smaller land holders and market gardeners. For example, Mr. H. Sampson, an orchardist near Alvin, has a surface well 12 inches in diameter and 36 feet deep, in which he put an 8-inch tubing. He asserts that from 15,000 to 30,000 gallons can be pumped from it daily by a windmill of sufficient size. Within the town limits of Alvin, Mr. W. H. Nash has a similar well which he states has never been pumped dry by a 10-foot windmill. He irrigates all the berry and garden crops which he "

Engineering News, Vol. XXXIX, No. 9, March 3, 1898.