The Arizona sentinel., 1896-07-18

of shei Gila and Colo-sdo rivers have fer the most part a deep sedimentary soil of brownish, gray san1y loSn, resting, in most places upon a gray clay subsoil at a depth of from ten to twenty feet below the surface, The clay subsoil forms a hard pan which is impervious to water These soils have been slowly forred by tlc decomposition of shalcs sandstones, inars. limestones, etc., mixed with or ganic and vegetable matter, washed down by the mighty rivers and have been gradually deposited during the course of centuries. The fertilizing -5Eown:sh zsad hnld in the wat tlof the Colorado and Gila riyers resembles that from the Nile, and its quantity varies from o.1 to O.5 per cent, though the water when even considerably discolor- ed by mud is good to drink, resembling in this pect the Missouri river water. A chemical analysis of the sediments of the Colorado and of the Nile exhibits wonderful similarity in the constituent parts of each, That of the ColoSade exhibiting a trifle hess potassa, most phosphoric acid and car bonade of limestone beds through which the Colo rado pGss"s In other respects the scjaasu. O; tle Colorado is almost identical with that of the Nile
 It will be noticed therefore, that when this water is used for irrigation it is superior to artesan waters since 1t is constantly supplying the land with the richest feFtlzing elements 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, dccoaposes the organic matters that they can be taken up and nouTish the plants which may De considered a leading featur, in its fertility. It also readily takes up and retains moisture, while the frmness of its particles affords every facility for percolation and the activity of capillary action. In its mechanical composition its particles are in state of very fine division, which renders t more productive than coarser soils It acquries heat readily in the daytime, and the loss of the heat at night is very gradual so that it re- mains always warm and is not subject to sudden changes of heat and cold Besides it's essential stituents of water, organic or vegetable matter, sand and clay, chemical analysis shows that lime, soda, magneSia, iron, ammonia and available forms of nitrogen, phosphorc acid and potash entor into composition in the proportions best adapted to add to it's fertility, though, of course is always the casa in soil analysis, its composition varies in different localities and is not always constant.
 The soi O the uplands, or meSas, lighter and more gravelly and in some places of a lree, loamy calcareous character. The mesa lands warm and generous. They seem especially adapted for the grape olive and citrus fruits generally. Their soi contains more magnesia, lime or chalk than the bottom lands. It never cracks and retains moisture admirably in summer. It is of that character which will produce wine that will keep good for fifty ol hundred years, and improve annually, not being
 liable to sour, or on exposure to the air, after year old, to become turbid and change color in tho bottle or glass.
 We can safely say that the soil of Yuma County can nowhere be surpassed, containing it does all tho essential elements of richness and fertility.