The Arizona sentinel., 1900-10-24
CASTLE DOME DISTRICT.

| The veins Of the Castle Dome district may be said 10 have been rediScoyered in 1863, for it was evident that they had been anciently worked as already stated in the historical introduction. The metal had been taken out from many of the veins by the ancient miners down to depth of from to 15 feet and in continuous lines of trenches, in some places for 50 to 100 feet or more. These old workings were found to be safe guides to good metal bearing ground a short distance deeper. Well worn trails leading of from these pits to the banks of the Gila river, some IS miles distant and the ruins there of some rude smelling furnaces, indicate that the ores were carried to the Gila, probably on the backs of Indians, and that they were Smelted there, whether by the Aztecs or the early-arriving Spanish explorer is not known. Since 1863 these mines have been worked almost continuously, and are now yielding silver-lead ore of most excellent quality, which is shipped to San Francisco. The claims were worked by the prospeetors without capital until October, 1870. Up to January l. 1892, there had not been an investment of over $500 in building or per manent improvements. The climate is such that men can work the year round without no more protection than is afforded by brush huts or tents.
 The veins crop out on a rolling plain or mesa at the base of the Castle Dome range, a very rugged and picturesque group of mountains trending northwest and southeast rising near the center to the remarkable dome-shaped sum- nit wish precipitous sides, looking like huge round castle or building with a dome. It is a noted landmark, being visible from great dis tance in all directions. It was originally called Capitol Dome by the officers at Fort Yuma in l252 fanPiad fo floa of the capitol at Washington. This mountain range being but sparingly watered, has never been convenient to prospect and very little is yet known of it's structure or mineral value. The mines arc usually reached from Yuma by driving to Gila City and thence to the mine, from l6 to Is miles east and inland from the river. The claims are numerous. Some have been patented and worked to a depth Of 300 feet or more. The veins are re- u2arkably regular and well forz1cd. The orc is galena, carrying about 30 ounces of silver to each ton. The veins trend in a general northwest and southeast course and are nearly vertical. The ou5cr0ps arc in dicated by outlying -Gassos and weather worn crystals or fourspaT. which is the chief vcinStone Calcite and gypsum are G-s0 found, and in some of the veins there is 9 vein stone Of quartz dispersed iG sheets or combs along the walls or in disyinc5 sheets in the center. Manganese spar and 5ari5e are also as sociated in layers. The thickness or power Of these veins is usually from to feet, sometimes from to F feet, wide. There are veins also only few inches in width. In general the veins are well filled with ore. This ore occurs in sheets or punches scattered through the vein- stone and commonly known among the miners as ball metal. In one mine in the district mass of nearly solid ore 8 feet thick was found
 At or near the water level, where the galenite has decomposed, both carbonate and sulphate of lead are found associated with pale-green f1uorite and an abundance of crystalized yellow wulfenite, another occurrence giving evidence of the presence Of molyhdenum in galenite.
 The rocks of the district are compact fine grained mica and clay Slates standing nearly on edge and traversed by numerous dikeS or intru- sive masses of a chocolate-colored porphyry.
 THE CHA VALLEY.
 The Gila valley extends from the Gila canyon near the junction of the San Pedro river, west erly to the east bank of the Colorado, a distance of slightly exceeding 250 miles. That portion of it situated in the county of Yuma, known as the Lower Gila valley, is about 100 miles long and from to 10 miles wide, all of which is SuScept- ible of profitable cultivation. The river from which it takes its name cuts the valley in two. Its watershed extends some 50 miles north and upward of 50 miles south Of it's channel, the land from either extreme inclinng more or less rapidly toward the stream. The Gila traverses a marvclously fertile country, very great in extent, and splendidly adapted to the cultivation Of nearly all the products of the temperate and Sezni-tropic zones, besides many of the fruits common in the tropics Nor is this longer a matter of idle speculation, for fouriShing ranches in various portions Of the valley, drawing water from several important canals, amply demonstrate the magnificent be rendered permanent, equable and adequate through appropriate storage systems.
 This consists of a broad eXpanse of tIllable valley land sometimes OverdOwed by the river which is at times mighty uncertain, and a steep range of volcanic hills coming close to the high ways, for dozen miles CT sO hot. heavy, sandy, It is hardly fair to say sandy as it is really g. friable alluvial soil of grayish hue and loose texture. Several ranches are passed, showing that the Gila bottom is cultivated. With irri- gation every square mile of the Gila valley is capable of producing prolific crops of grain and Semi-tropiCal fruits, as well as cotton and sugar in great abundance. The river is able to fur nish all the water needed and good deal more. It would take no great skill in engineering and not . very large sum Of money either to con-