The Arizona sentinel., 1900-12-19
CASTLE DOME DISTRICT.

The veins of the Castle Dome district may be said to have been rediscovered in 1863, for it 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 proSpectorS without capital until October 1870. Up to January 1, 1892 there had not been an investment of over S3OO 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, very rugged and picturesque group of mountains trending northwest and southeast rising near the center to the remarkable dome-shaped sum- init with precipitous sides. looking like huge round castle or building with dome It is a noted landmark, being visible from great dis tance in all directions. It originally called Capitol Dome" by the officers at Fort Yuma in to 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 its structure or mineral value The mines are usually reached from Yuma by driving to Gila City and thence to the mine, from 16 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- markedly regular and well formed. The ore 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 outcrops are in dfcated by outlying masses and weather worn crystals of fiourspar which is the chief veinstone. Calcite and gypsum are also found, and in some of the veins there is vein stone of quartz dispersed in sheets or combs along the walls or in distinct sheets in the center. Manganese spar and barite are also as- sociated in layers. The thickness or power of these veins is usually from to feet, sometimes from 8 to l2 feet wide. There are veins also only a 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 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 a pale-green fiuorite and an abundance of crystallized yellow wulfenite, another occurrence giving evidence of the presence of molybdenum in galcnite.
 The rocks of the district are compact fine grained mica and clay states 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, 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 3( miles north and upward of 50 miles south of its | channel, the land from either extreme inclining more or less rapidly toward the stream. The | C4ila traverses a marvclOusly fertile country very great in extent and Splendidly adapted tC the cultivation of nearly all the products of tho temperate and seni-tropic zones, besides many | Of the fruits common in the tropics. Nor is this longer a matter of idle speculation, fol tourishing ranches in various portions of tht valley, drawing water from several important
 canals, amply demonstrate the magnificen results that will cnsue should the water suppl! be rendered permanent, equab!e and adequate
 through appropriate storage systems.
 l This consists of d broad expanse of tillabl, valley land, sometimes oycrfowed by the river
 which is at times mighty uncertain, and steel range of volcanic hills coming close to the high
 ways for a dozen miles or so, hot. heavy, sandy
 It is hardly fair to say sandy as it is really
 friable alluvial soil of grayish hue and looS
 texture Several ranches are passed, showing
 that the Gila bottom is cultivated. With irri
 gation every square mile of the Gila valley i
 capable of producing prolific crops of grain anC
 seni-tropical fruits. as well aS cotton and suga
 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 ant not q 5ery large s.lm of money either to con