The Arizona sentinel., 1896-12-05

of hei Gila and ColorSao rivers have for the most part deep sedimentSSy soil of brownish, gray shn1y Team, resting, E most places upon gray clay srbsoil at depth of from ten to tweaty feet below the surface, Ths clay subsoil forms hardi Ps2 which is mperviers to water. These soils have been slowly formed by the decomposition of shsles SandstoneS, marls. 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 teFtilizing brownish mud hcld in the wat tlof the Colorado and Gila rivers resembles that from the 'Nile and Its quantity varies from O.l to 0.5 per cent though the water when even considerably discolor- ed by mud isgood to drink resembling in this res pect the Missouri river water. A chemical analysis of the sediments of the Colorado and of the Nile exhibits awonderful similarity ia the constituent parts of each. That of the Colorado exhibiting trife less potassa, most phosphoric acid and car bonadeof limestone beds through which the Colo rado passes. In other respects the sediment of the 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 aresan waters since it is constantly supplying the land with the richestfertilizng elements. The soil of the valleys
 
 and uncombined carbon, readily absorbing the aerial gases, such especially, as oxygen, which tering the soil, decomposes the organic matters that they can be taken up andnourish the plants which may De considered "a leading feature in its fertility. It also readily takes up and retains moisture, while the frmness of it's particles affords every taciity for percolation and the activity of caIsfary action. In ts mechanical composition its particles are in state of very fine division, which | renders it more productive than coarser soils It acquires heat readily in the daytime, and the loss of the heat at night is very gradual so that it mains always warm and is not subject to sudden changes of heat and cold. Besides its essential stituents of water, organic vegetable matter, sand and clay, chemical analysis shows that lime, soda, magnesia, iron, ammonia and available forms of nitrogen, Phosphoric acid and potash enter into composition in the proportions best adapted to add to its fertility, though, of course is awa. thecass in soil analysis its composition varies in 'dlferent localities and is not always constant. The sol o the uplands or mesas, lighter and more gravelly and in some places of .ree, loamy, 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. It cracks and retains moisture admirably in summer. It isof that character which will produce wine that will keep good for fifty or hundred years, andi improve annually tbeing liable to sour, or on exposure to theair after one year old, to become turbid and change color in the bottle or glass.
 We can safely say that the soil of Yuma County ran ho ooad int, the essential elements of richness and fertility.