galena, 122.47 ounces silver. Higher up on the mountain the galena in the same lead is very solid and contains 57.5 per cent. of lead.

Mr. Peabody worked another vein on the same side of the river, specimens from which assayed 61.5 per cent. of lead, 55.5 ounces silver, and 0.17 ounces gold per ton.

Castle Dome district.-This district is situated opposite a point on the Colorado River, thirty miles above Arizona City and inland to the east about twenty miles. It was organized in 1863 and 1864, and some of the mines have been in operation more or less ever since. The district has its name from a dome-shaped butte, which towers several hundred feet above the crest of the mountain chain, and is visible for great distances in all directions.

Castle Dome district has a very rugged surface, and the mines are not easy of access. Water is rather scarce, and wood is confined to cottonwood, mesquite, ironwood, and palo verde, the first only near the Colorado, while the two latter kinds occur in limited quantity in all the dry washes and ravines from the mountains.

The Castle Dome Mountains are an isolated range running northwest and southeast, and extending twenty-five miles from a point near the Gila toward the northwest. The range is entirely destitute of vegetation. The rocks constituting it are granite, metamorphic slates, basalt, and porphyries; the erupted rocks especially give to the outlines of the chain that ragged appearance so characteristic to it.

Prospecting in the mountains proper has so far been devoid of satis factory results. Exceptional seams of yellow and blue talcose clays are met with; also several large veins of hard, dense quartz, slightly tinged with oxide of iron, but they are not auriferous. One of these veins can be traced through the mountains for several miles, having withstood the action of the elements, while the neighboring rocks were destroyed and washed away for many feet in depth. This ledge is from 3 to 20 feet wide, strikes north 400 west, and dips about 250 southwest. On one casing beautiful dark dentritic forms are seen, and pieces of this sometimes contain visible gold; but on the whole the vein is barren. The district was first entered by Americans in 1863, but old and aban doned mines with shrubbery of many years' growth upon their dumps, a well-beaten trail to the Gila, piles of slag and traces of ruined Spanish furnaces near that river, clearly demonstrate that this ground was known and worked by the Mexicans prior to the occupation of the country by Americans.

The founders of the district (as is related by one of them) labored under the delusion that galena was nearly pure silver, and that in the possession of mines here they had a "big thing." They suffered from want of water, provisions, and mining supplies; yet they worked here during the summer heat, Sundays and nights, as well as by day, sus tained by the consciousness of being in luck. No efforts were made to explore mines or to extract ores; all their energies were centered upon the acquisition of ground by posting notices and complying with the district regulations in regard to work, &c. Several months elapsed before satisfactory assays could be obtained, when the mere word "lead" destroyed their hopes, and dispelled their bright illusions as the splash of a stone effaces the reflection of scenery from the face of a placid lake. The reaction was great, and the disappointed miners were easily called away by the reports from La Paz, Weaver, and other rich placers. Castle Dome was again a solitude. Later, the establishment at San Francisco of smelting furnaces and lead-works created a demand for lead ores, which again brought this district into notice, and veins here were worked with varying success until the opening of sim

flar mines in California and Nevada, from being nearer at hand, diverted the attention and money of capitalists, who had been promoting operations down here. Many promising veins were abandoned for want of capital. This winter work has been resumed on several lodes with highly gratifying results. The books of one mine, the Flora Temple, show that the first 100 tons of ore were placed upon the dump, cleaned and ready for transportation at an expenditure of less than $900, which includes cost of tools, supplies, and every expense incurred in the discovery and opening of the mine. The ore is an argentiferous galena, and assays 63 per cent. lead and 39 ounces silver per ton. The mines are perfectly dry, no moisture having been found at the greatest depth yet reached. On the score of security, economy, and facility for working, the absence of water underground amply compensates the trifling inconvenience of having to use it from barrels. Water is hauled to the mines from the Colorado River by the teams employed in carrying ores down to the landing. Fuel is abundant in the ravines, which are well stocked with a species of lignum-vitæ, known here as "ironwood." The country rock in the small district in which mines are actually worked is slate and granite. The most prominent lodes appear to be true fissure-veins, running north-northwest and south-southeast, dipping indifferently to east or west. The principal characteristic is a gangue of fluor-spar, tinged pink or green, and sometimes beautifully crystallized. The Castle Dome mine, now being worked with great vigor, contains 2,200 feet, acquired by location and purchase. One hundred and sixty feet have been opened and worked to the depth of 56 feet, producing some 500 tons of shipping ores. The greatest depth attained in exploration is 104 feet. Surface explorations clearly establish its continuity. It is producing ores of excellent quality, assays of metal now in transitu to San Francisco ranging from 58 per cent. to 69 per cent. lead, and $23 to $190 silver per ton.

This mine is particularly interesting from the diverse character of its contents and the beauty and richness of many of their combinations. Sulphurets and carbonates, and a half-decomposed galena, dull in color and exceedingly rich in silver-chemical composition as yet unknown-are generally selected for shipment; the poorer carbonates and sulphurets being retained with an ultimate view to smelting at the mine or at the Colorado River. The strike of the vein is north 44° west; dip, 15° west. The foot-wall is a talcose slate, with a pink tint. The vein-matter contains many combinations of clay, tale, gypsum, fluor-spar, &c., of constantly varying color and consistency. The vein proper varies in width from 2 feet to 8 and 10. The shipping-ore generally occurs in compact seams, from 3 inches to 2 feet in width, though frequently met with in kidney-formed masses in spar and in the argillaceous and talcose vein-matter. The expense of extracting and cleaning the ore varies with the character of the vein. The following figures will be found as nearly correct as it is possible to give

them:

The Buckeye was worked very profitably last spring, until the ap proach of hot weather, by Messrs. Butterfield. Work has not been resumed yet this winter, though the mine shows plenty of ore and invites labor. It is of the same general character as the Castle Dome. The Flora Temple was first opened this winter; has three incline shafts sunk to a depth of 50 feet, and the necessary drifts to facilitate communication and ventilation. From this limited amount of work (the stope remaining untouched) 150 tons of clean ore have been extracted.

The Poorman is yielding galena of first-rate quality, and its owners appear well satisfied.

The Prosperity, Don Santiago, Nonpareil, and other veins, are being prospected with very promising results.

I am indebted for much of the above information to Mr. Geo. Tyng, superintendent of the Castle Dome mine, and to Mr. Julius Sieback, a mining expert of Arizona City, who has had much experience in the Colorado River mines and elsewhere.

The placers of Gila City.-Some sixteen to eighteen miles east of Arizona City, the Castle Dome range crosses the Gila. On the low foothills on both sides of the river, the valley of which is here about a mile wide, and in all the ravines and gulches in them, occur gold placers. They have been worked for many years, and although they have been worked over by dry-washing to a great extent, they are still rich in fine gold, which could not be reclaimed by that process.

The main mountain range consists here of granite and syenite, which is traversed by greenstone dikes. The foot-hills consist altogether of metamorphic slates, which contain a great number of small gash-veins and bunches of iron-stained quartz. As in the case of the La Paz placers, I think that the gold in the placers comes from these slates.

The placers extend along both banks of the Gila for ten or twelve miles, and several small towns like Gila City, Los Flores, and Oroville, owe their origin to the first gold excitement. They are now deserted and only inhabited by a few white men.

At Gila City a San Francisco company has during the last year erected works to pump the water from the Gila up into a reservoir on top of the highest foot-hills in order to work the placers of the vicinity by hydraulic power. They use a 9-inch pipe through which they pump the water, and their works had just been completed when I left the Territory. The first run they had made satisfied them of the value of the placers, and they were eager to continue their operations.

The gold shown to me was mostly coarse, but of very fine quality, being worth $19 75 per ounce. I was told that their apparatus for saving the fine gold had not been completed, but was to be put up soon. If the gold left in these placers is really sufficient to pay for such an expensive way of working them, the field is undoubtedly sufficiently large to last for years.

At Los Flores, on the opposite side of the river, a small five-stamp mill has been at work for a part of the year crushing gold quartz from some small veins in the vicinity. The enterprise seems to be a success, as an addition of five stamps to the mill is contemplated.

Most of the placer-mining in the vicinity is done by Mexicans and Indians, and for that reason it is very difficult to get any reliable data as to their yield, unless the shipments of Wells, Fargo & Co.'s office at Arizona City may be taken as a criterion. These amount to little less than $75,000 during the year, but much of this comes undoubtedly from other sources in the Territory.

PIMA COUNTY.

This county comprises all that territory in Arizona lying east of longitude 1130 20', and south of the Gila River. Next to Yavapai it is the largest in the Territory. It contains some of the most fertile agricultural lands in Arizona, principally in the bottoms of the Gila River and its tributaries, all of which, however, require irrigation. The great expanse of country to the southwest and south of the Lower Gila is barren, and, in fact, a continuation of the Sonora Desert. The level surface of the Tertiary plains is here only broken by the appearance of numerous small mountain-chains, the rugged outlines of which are visible for great distances.

The first mining in Arizona by Americans was done in this county, but before them the Mexicans had for years extracted the precious metals from these domains. Old mines, now mostly caved in, and the remnants of ancient beneficiating works, especially in the southeast corner of the county, amply confirm the traditions of the Mexican population in regard to this.

The Ajo copper mines are located sixty miles south of Kenyon Station, on the Gila River. Kenyon Station is one hundred and thirty miles east of Arizona City. This makes a land transportation of one hundred and ninety miles to the Colorado, over a good natural road; the first sixty miles, however, are entirely destitute of water.

There are several veins in the district, all of which occur in granite and slate; strike northeast and southwest, and dip steeply to the southeast. The principal vein contains solid peacock ore in a fissure 27 inches wide. The main shaft is 150 feet deep, and in this water was struck at a depth of 140 feet, which had to be carried out on the backs of Mexicans. Several drifts and galleries were run from this shaft, in the majority of which the body of ore is much split up; in others it thins out to mere thread. The longest level is 100 feet in. In another vein the gangue is white quartz, which contains native copper, red oxide, and carbonates. It is 18 inches wide and a shaft is sunk upon it to the depth of 90 feet. From this a level is run 30 feet from the surface, 60 feet long; and another, 45 feet below the surface, is driven in 30 feet. The ore-streak in the vein is on an average one foot thick. Water was struck in this shaft also.

There are several other shafts on these veins, from 20 to 60 feet deep. In the latter, which is on the first-mentioned vein, only decomposed ores, very solid and rich, had been found.

There is much mesquite wood in the neighborhood, and water was struck in a ravine, in two wells, within 20 feet from the surface. Work is temporarily suspended on these mines, and will be resumed as soon as the completion of the South Pacific Railroad, opposite this point, on the Gila, will lessen transportation. The ores are extraordinarily rich and well fitted for concentration by a single smelting on the spot into at high-grade crude copper.

The country south of Tucson, in the neighborhood of Tubac, I have not visited. It was originally my intention to pay a visit to these regions and report upon the mines which had at one time such an excellent reputation and on which so much labor and treasure have been expended in the past. After waiting at Tucson over two weeks for an escort, (for no part of Arizona is worse infested with Apaches, and a small party of white men cannot safely travel in these regions,) and seeing no prospect of getting one without waiting three or four weeks longer, I concluded to turn north and examine some other portions of H. Ex. 10-18

the Territory. This resolution was hastened upon learning that no work whatever had been done on those mines for years, and upon reflection that, in that case, I would not be able to see enough in the broken-down shafts and drifts to repay for the long trip. At the same time Mr. J. Ross Browne, in his report of 1868, has treated these mines so fully, at a time when there was much more and better opportunity for examining them, and he has quoted such excellent authorities in that report, that I am fully satisfied that all has been said in regard to these mineral veins and their development that ever was learned by working them. From that report we must conclude that this part of Southern Arizona is full of veins, principally carrying true silver ores, which appear to occur under the same geological conditions as the sil ver veins of Northern Mexico, viz, in porphyritic and granitic rocks, or as contact-veins between these eruptive rocks and sedimentary strata, chiefly limestones.

Some of these veins have been worked in an exceedingly extravagant way. According to the reports of Kuestel, Pumpelly, Brunckow, Schuchardt and other noted mining engineers, it is certainly not the fault of the mineral deposits that they do not support flourishing mining enter prises even under the present high cost of transportation, but entirely of the management and the hostility of the Indians. The South Pacific Railroad will do away with the Indians and high transportation, and it remains to be seen whether the future managers of these mines will have profited from the dearly-bought experience in mining all over the 'West.

The Lee and Scott mine, about twelve miles due west of Tucson, has been worked to some extent to within a year or two ago. But although this mine is almost in sight of the capital of Arizona, the Apaches have driven off and killed the miners, and rendered work upon the lode impossible. This vein contains a mixture of galena and fahlore very rich in silver, the portion reduced on the spot having yielded at the rate of $125 per ton. Governor A. P. K. Safford, of Arizona, who has lately visited the mine, says in regard to it:

The course of the lode is west-southwest to east-northeast; near the surface its width is 18 inches. The hanging-wall is smooth, but the foot-wall is somewhat broken, and near it are about 6 inches of very concentrated mineral. For the first 80 feet in the shaft the dip of the vein is very regular 450, but at this point a large horse comes in and the ledge nearly pinches out. Below this horse, which is only a few feet thick, the vein becomes much nearer perpendicular and widens out. At 90 feet, water in small quantity was struck, and several feeders join the main lode. At the bottom of the shaft, 100 feet from the surface, the ledge is about 5 feet wide, inclosed in plain walls, and the mineral seems well distributed through the gangue. The character of the ore is the same as shown to you (galena and fahlore.) I could trace the croppings

for some distance on the surface.

In this district there are also some very rich copper and lead mines containing silver, several of which have been worked profitably in times past. But the constant depredations of the Apaches caused the death of many of the workmen and owners and rendered it impossible to keep any live stock; so work had to be abandoned. Could we have protection I am certain many of these mines, as well as a great number of those south of here, could be worked now to a profit.

The following description of the country in the southeast corner of Arizona Territory, between the Rio Salado or Salt River on the north and the Sierra Cananea of Sonora on the south, and between the Rio Santa Cruz on the west, and the Sierra Dragones and the one hundred aud ninth meridian of longitude on the east, has been kindly furnished to me by Lieutenant John G. Bourke of the Third Cavalry. This sketch was compiled from notes collected during the numerous scouts of Troop F, Third Cavalry, and especially during the one made in conjunction with the volunteer troops acting under the command of Governor A. P. K. Saf