The Arizona sentinel., 1895-11-02

of the Gila and Colorado rivers have for the most part deep sedirnentary soil of brownish, gray sandy loem resting, ia most places, upon gray clay su5soil at a degth of from ten to twenty feet below the surface, The clay subsoil forms a hard pan which is imperyoCs to water. These soils have been slowly formed by the decomposition of shales, sandstones, marls. lmestones e5e., mixed with or ganic and vegetable matter, washed down by She mighty rivers and have been gradually deposited during the coarse of centuries. The fertilizins Lronnish mud held in the wat tlof the Colorado and Cila rivers resembles that from the Nile, and its quantity varies from O.I to O.5 per cent, though the water when even considerably discolor- ed by mud is good to drink resembling in tbs res- pect the Missouri river water. A chemical analysis of the sediments of the Colorado and of the Nile exhibits a wonderful similarity in the constituent parts of each That of the Colorado exhibiting a trife less potassa, most phosphoric acid and ear b9nade of limestone beds through which the Colo rado passss Tn other respects the sediment of the Colorado is almost identical wi5h that of the Nile. It will be noticed therefore, that when this water is used for irrigation 1t is superior to aresian waters since it is constantly supplying the land with the richest ferilizng clements. The soil of the valleys is extremely rich in dedomposed vegetable matter and uncombined carbon, readily absorbing the aerial gases, such especially, oxygen, which en- tering the soil, decomposes the organic matters so that they can be taken up and nourish the plants which may he considered a leading feature in it's fertility. It also readily takes up and retains moisture while the frmness of its particles affords every taciity for percolation and the activity ot capillary action Tn ts mechanical composition its particles are in state of very fine division, which renders it more productive than coarser soils It acquirics heat readily in the daytime, and the loss of the heat at night is very gradual, that it re- mains always warm and is not subject to sudden changes of heat and cold. Besides its essential con stituents of water, organic or vegetable matter, sand and clay, chemical analysis shows that lime soda magnesia, iron, ammonia and available forms of nitrogen, phosphoric acd and potash enter into composition in the proportions best adapted to add to it's fertility though, of course as is always the case in soil analysis its composition varies in different localities and is not always constant.
 The soil of the uplands, or mesas, lighter and more gravelly and in some places Of free, lOamyi calcareous character. The mesa lands are warm and generous. They seem especially adapted for the grape olive and citrus fruits generally. Their soil
 contains more magnesia, lime or chalk than the bottom lands 1t never cracks and retains moisture admirably in summer. It is of that character which will produce wine that will keep good for fifty or a hundred years, and improve annually, not being liable to souri, or exposure to the air, after one year old to become turbid and change color in tho bottle or glass.
 We can safely say that the soil of Yuma County nowhere be surpassed, containing as it does all the essential elements of richness and fertility.