The Arizona sentinel., 1901-03-13

struct reservoirs or lakes in which to receive and sore the overflow There are natural basins or dry lakes into which by simple
 means the water could be conveyed.
 The lands situated in and about the Gila val ley may conveniently be classified as follows: First. the bottom or overflow lands; ,. slightly higher valleys. lands subject lo uo overflow; &
 mcsas or sloping UpIands: l. high but conp2r atively level plains: ,, mountains.
 The bottom lands. aS well a. those slightly higher. stretch along either SGo of the Gila and ] Colorado rivers for varying distances north and south until they meet the moro elevated mcSaS which rise from the valley. The bottoms lie directly along the river and arc subject to inUE- dation annually. unmcG2tcly following the subsistence Of the waters the local Indians were l in former times accuuato.Eed to plant corn ] pu:npllins. melons and other vegetables. These l spring into maturity w.h startling rapidi5y rarely failing to yield 0ountifllly without aGdi- i tional irrigation. The custom K occasionally | followed by resident farmers 10 this day. with | excellent results although bat single crop can l be harvested. These bottoms form . per cent Of tho valley lands, and may without difficulty be secured from further invasion By a system Of dilles and leveeS. if deemed necessary and de>iT- able The soil throughout the valley x 8 rich brownish yellow sandy loGm. generous. mellow. porous, with q depth ranging from to 20 feet. the whole resting upon underlying strata of gravel end sand that readily carry from the surface such excess Of water as might ojhC rwiee prove injurious to seeds and growing plants.
 Concerning the geological formation of these lands the following from the report of the citizens executive committee k sufficiently comprehensive:
 There iS unmi~takabie geologic evidence that all this land during some prehistoric period vas covered with water. constituting in fact an euormouS lake. the surfaces rising in places to upper portion e the outSlirting mcSaS The soil lying at the bottom was made by the washing and erosion Of the surrounding mountains. The soda from the decomposed vegetation the mag ncSia and lime from the raagnesiun-iime forna- tiOnS, and the potash from the dec0mposing granite rocks were carried with unceasing re- gularity year by year. until deposited in the bottom. Eventually upon the disappearance of the lake. the rich fertile alIuvium. than which there k none bc.tcr was left to reward the efforts of the modern huSbandmen. But nature. not yet satisfied with her handiworll directed the accumulation Of the GetrituS washed from the distant mountainous region. A result, the soil k extremely rich in the elements best adapted to thorough fertilization. forit contains a certain amount of organic matter which. on decolnpoSing. further enhances it's agricultural value. By constant overflow and change of channel the deposits are evenly distributed over considerable areas. the process continuing through centuries These soi3> are further cn- richcd by decomposed organic contributions. nclGdirg the san,l~toncS Inarls. lilaess0nes. shalcs. etc. Besides the Ingredients mentioned. a chemical analysis shows that iron. ammonia. and phoSphoriy a i'd enter into it's composition in the proportions best adapted to add to it's productive qualities. The extremes of tcnpera- ture are somewhat greater than on the high lands, bat there is also more moisture.
 The bottom lands are 90 easily cultivated that 1t k not uRconmon after clearing the sur face from the bruNh and StUbb!e. to pass over the ground with an ordinary cultivator single time. afterwards sowing to grain and grass. Tn three or four months large crops are harvested. the soil meanwhile being entirely innocent ot the piOw Al plants seem to grow rapidly. piaturug remarkably early. Indications Of aI-- cj"ut GiTCheN are apparent throughout the val Icy. showing plainly the existence of irrigation works hy the ancient AZtecS. CuriGuSly enough. in certain instances. the identical routes or these long extinct people have b"eI followed fer cCdSderUtablC distances by their modern sue CC>SUr~.'