Chemical analyses of Nos. 1 and 7 were also made in the laboratory of the Geological Survey to test the uniformity of the deposits. These samples were found to differ slightly from those sent to Mr. Duryee, but still are eminently suitable for the purpose. The following are the results found in the Survey laboratory: Analysis of limestone from Salt River, Arizona, made in the laboratory of the Geological Altogether these results are gratifying, and prove beyond question the existence of convenient and abundant materials from which cement can be made. The greatest difficulty is the scarcity of fuel. There is a considerable quantity of wood in the reservoir site, mainly cottonwood and mesquite, which it will be desirable to clear out of the reservoir in any event. Wood is not suitable for burning cement clinker by modern methods, but if made into charcoal and then ground to powder would answer; or oil may be imported for the purpose from California. The cost of the cement plant, with machinery capable of producing 300 barrels per day, is estimated by Mr. E. A. Duryee to be as follows: Approximate cost of a rotary process, two-kiln Portland cement plant of a daily capacity of 200 barrels. 300-horsepower electric motors and step-down transformers. 9,000 With such a mill the cost of manufacture would be approximately as follows (allowing for power only the proportion necessary for maintaining and operating the electric plant provided): Cost per barrel of making cement at Salt River dam site, Tonto Basin. Estimated cost of Salt River storage dam. [247 feet above foundation; 190 feet available storage; capacity, 840,000 acre-feet.] 257,420 cubic yards rubble masonry, exclusive of power and cement, The cost of a dam 20 feet lower, storing 600,000 acre-feet, would be practically the same for all items except the masonry and cement, which would be about 20 per cent less, making the total cost about $1,680,000, or $2.75 per acre-foot capacity. These estimates are based upon the data at hand, May, 1902, and are subject to modification. CALIFORNIA. In California, especially in the southern portion, irrigation has reached its highest stage of development, and the largest proportion of irrigable land has been brought under cultivation. There are, however, throughout the State, a number of rivers of large volume, whose waters are not completely utilized. Most of these have their |