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Zeutschel OS7000, 400 dpi, 8 bit, 18,754,024 byteswith vegetable matter washed from the mountains, it being perhaps the original bed of the ocean, that once covered this country. These plains are dry and barren, being covered sparsely with cacti, sage, brush, and similar growth. In this section of the Gila Valley all crops are grown by the aid of irrigation. In extent this vast plain embraces thousands of acres, while the water supply as compared to the amount of land susceptible of cultivation is very limited, and unless ways and means are devised to store and save the immense floods of water from the upper Gila section that semi-annually run to waste in the Gulf of California, there will be but a limited portion of these vast plains, of as good land as anywhere exists, ever brought under cultivation.The canals taken from the Gila in the vicinity of Florence cover about 300,000 acres of land, including 50,000 acres on the Pima Indian Reservation. These canals nearly exhaust the water at ordinary stage, although they furnish a superabundance of water in the spring of the year in crop season, and also when the summer rains comes early in the upper Gila, to make a second crop; but there occur usually two short periods in each year when there is a scarcity of water in all the lower valley, say, from three to six weeks in June and July and again about the same length of time in November and December; especially during the latter period is the amount needed usually limited.When the water in the upper Gila gets low, immediately after it passes through the gorge at the Buttes, where the bed-rock comes to the surface, it largely disappears in the gravel bed that underlies the plains in the lower valley. Canals that are taken out immediately below the Buttes have a steady and consistent supply of water, while those lower down get none in low water, except at a few places where the bed-rock comes to the surface. Notwithstanding this the entire volume of the river might be turned down to the lower sections if it were possible to raise the level of the water sufficiently through the agency of a reservoir. The many thousands of acres of the most valuable land in these lower plains before noted can be successfully brought under cultivation at a comparatively small cost to each acre by constructing a dam in the Gila River at the place above mentioned at the Buttes, some 10 miles above Florence.A dam constructed there would store a sufficient quantity of water when the river is flush in the two rainy seasons to insure a steady flow of water in all the canals now in use in this valley, and allow a sufficient surplus of water to guaranty the construction of another canal to be taken out of the river at the Buttes of the south side of the river. The capacity of this canal can be as great as all other canals, and would water some of the finest land ever looked upon. This statement may seem an extravagant one, but upon examination of the accompanying map, showing the topography of the country above Florence, at and above the Buttes, it is readily seen that an enormous basin of water can be formed by constructing a dam at that place. It appears that a dam 150 feet high will back the water about 20 miles, giving probably an average depth of some 75 feet for the entire distance. The cañon of the river immediately above the Buttes widens out, and at a distance of one-fourth of a mile it is as much as one-half mile wide on the bottom, and much of the entire distance it is a mile or more wide. The sides of the mountain surrounding this basin are broken by side or lateral cañons that add greatly to the capacity of the basin. The conception of the capacity of such a reservoir can only be appreciated by the engineer and study of such spaces. No cross-sections of this basin have ever been made, as far as known, to calculate the vast volume of the basin, but the above statement it is believed is not overdrawn, and that an accurate survey will increase this estimate. There can be no doubt of the water supply being sufficient to fill this vast reservoir when a dam is once constructed, as a glance at the rain-fall data in the water-shed covering southwestern Arizona, a large part of western New Mexico and Sonora will prove. It is believed this water-shed will not only furnish water for this ideal reservoir, but will also supply many other reservoirs, smaller in capacity, that can be constructed at different places in the lower Gila River valley, and from which many thousands of acres of valuable land can be reclaimed.The above facts seem to me so patent that it is respectfully urged that this place be investigated for early experiment and surveys in Arizona, under the Government, as there are few spots in the United States, and certainly few in Arizona, where so much can be accomplished with so small an expenditure of means. Indeed, to the person who has looked at the place with the object in view it appears as if nature had largely made this extraordinary place for the purpose.A dam about 200 feet wide at the bottom and 100 feet high, though the height might be doubled, will, it is believed, accomplish the results heretofore outlines. At this place the best rock, almost in place, can be quarried for constructing the dam, and in the immediate vicinity good hydraulic lime can be burned, as is now done by the Mexicans for use by the cattle men for the purpose of constructing water tanks. With all these advantages, and many other not enumerated that will be found to exist when properly examined, the Government can not too early turn its attentio