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Belonging to and being worked by the same parties, contains a large body of low-grade ore, which can, however, be broken and delivered to the mill very cheaply. The ore carries from 2 to 5 per cent of a lowgrade sulphuret, averaging from $20 to $50 per ton, and the body of it shows a width of from 100 to 150 feet. A ten-stamp steam mill was put up for prospecting purposes. An open cut with a face 75 feet across has furnished most of the ore crushed. The foot wall here is serpentine, the hanging wall slate.

THE KINCAID FLAT MINING COMPANY.

Three miles southeast of Sonora and east of Jamestown, near the contact of the slate and gneissoid rock, the above company own 160 acres of ground, where they are working a gravel deposit. From Sullivan's Creek a tunnel has been run, starting at Sullivan's Bar and running 3,000 feet under Kincaid Flat. A shaft 140 feet in depth was sunk, but neither tunnel nor shaft touched bedrock; the shaft could not be sunk any farther, on account of the difficulty of handling the water. The gravel is from 40 to 50 feet wide, not cemented, and pitching like a vein, at an angle of about 45° to the east. What would represent the foot wall is a greatly decomposed rock, having lost all structural features. The gravel carries coarse gold, valued at $19 per ounce. It is washed by hydraulic process. Curtis Creek, to the south, furnishes 600 inches of water under 160-foot pressure, which is delivered against the gravel through a Giant No. 3, with a 3-inch nozzle. The flume is 2 feet in width and about 1,200 feet long, with a 2-foot fall to 100 feet; a part of the flume is paved with block riffles, and the rest with slats, but the expense of renewal of these latter being too great, the blocks will be used throughout in the future. Except in a general clean-up the first 120 feet only is cleaned. The open cut beyond the tunnel is 550 feet long, 50 feet wide, and the bank about 60 feet high. The east side is a gneissoid rock, the west a slate, pitching about 80° to the east. The hydraulic pipe is 11 inches in diameter, made of No. 16 iron. The flume and tunnel cost in construction $85,000. Some part of the slate cost $30 per foot to drive through. At present four men are at work, who receive $3 per day.

THE GOLDEN GATE MINE,

One of the most prosperous mining undertakings in the county, with a complete plant, is within a mile of the town of Sonora, and operates on a vein coursing northeast, apparently an offshoot of the main lode fissure. Since last reported on, the following work has been progressing: On the 200-foot level north of the shaft, on a pay shoot which extends for a length of 350 feet, the end not having been reached yet, the ground is being stoped toward the surface. On the 300-foot level north of the shaft, the drift has attained a length of 320 feet, and is still being continued to the south; the drift has been stoped a distance of 60 feet. The inclined shaft is down 470 feet, about 400 feet vertical. A new Rix compressor is to be put in for six drills, Ingersoll pattern. The shaft, which is in the foot wall, about 8 or 12 feet from the vein, in a dioritic dike, cost $30 per foot to sink; 180 feet of the shaft has been sunk since October, 1891, and the surface tunnel retimbered throughout. The opening of the entire 300-foot level and from there down to the bottom of the shaft has been executed since issuing the last report.

The chlorination plant has been erected for 3 tons per day, using an old-style Plattner furnace. The ore yields about 5 per cent of sulphurets of iron, lead, and copper, also arsenical pyrites and tellurides, which are saved on four Frue vanners with corrugated belts, canvas plants and settlers, and yield, by the chlorination process, 97 per cent of the assay value, the treatment costing $14 per ton. The furnace consumes two and a half cords of wood, valued at $4 25 per cord, for every 3 tons of concentrates. Since being started up the chlorination works have been idle only two weeks.

In the mill, which is run at the high rate of one hundred and five drops per minute on a 6-inch drop, 2 tons of ore is crushed per stamp, passing through a No. 30 screen. The wear on the chrome-steel shoes and dies amounts to 1 inch per week. The free gold is saved almost entirely on the plates. The power is water, taken from the Tuolumne Company's ditch under private contract, and is distributed as follows: Three wheels at the hoisting works-two Knight wheels 6 feet in diameter, and a home-made undershot for the compressor; a 6-foot Pelton wheel for the mill, a 20-inch Pelton for the concentrators, and an 18-inch Pelton for dynamo and lathe. The water at the mill is delivered under a 300-foot pressure, at the hoisting works with 260-foot head. A seventyfive horse-power engine with two tubular boilers is in reserve at the mill, in case of accident to the water power. Ten stamps with the necessary concentrators, among which will be introduced a new Danbury concentrator from Colorado, are to be added. All of the works use electric lights. About forty men are in the employ of the company; twentyeight of them are miners.

THE BIG BONANZA MINE

Is engaged at present in erecting an entirely new hoisting and pumping plant, which is about completed, when the mine will be drained and the work resumed. There will be three pumps-a Duplex, a Hooker, and a jack-head. The company take water from the Tuolumne Company's ditch, with 393-foot fall, applied through 3,000 feet of 11-inch pipe,

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taken from a drawing by J. C. Dart, M.E., shows the relative positions of the different parts.

A body of water equal to 8 miner's inches flows into the mine. As the mines of Tuolumne County are so much dependent on a close saving and beneficiating of their sulphurets to bring them to a paying basis, it is a move in the right direction that all the new mills devote considerable space to the erection of different kinds of concentration plants, while the older works are adding canvas platforms behind their mills to obtain closer percentages than heretofore. It is in this direction that the establishment of the Sonora Chlorination Works is a direct benefit to all the smaller mines that do not feel able to erect and maintain works of their own. These works are at present in the hands of reliable and conscientious men, and consist of a four-stamp battery with 750-pound stamps, apron, and small sluice plate, a Dodge crusher and selffeeder, a Tustin dry crusher mill, a sampling floor; a single-hearth, long, reverberatory furnace, 36 feet by 12 feet outside measurement, with nine working doors, and a capacity for 2 tons in twenty-four hours; three chlorination vats, one settler, and two precipitating tubs for silver, also a precipitating tank for cement copper, assay office, etc. They guarantee 90 per cent of the fire assay for all up to $50 per ton, higher percentages in proportion for richer ores. Their charges are $20 a ton for gold, $5 additional for silver. Three men are employed besides the manager.

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made of No. 14 and No. 16 iron, with 4-inch nozzle, acting on a 3-foot Dodd wheel. They have also a thirty-two horse-power engine for reserve power.

This noted pocket mine, situated within the town limits, has a vein coursing north 30° east, dipping at an angle of 30°, while the slates of the country rock have a course north 45° west. The vein is about 8 feet in thickness. The vein filling, consisting of a porphyritic dike, has a casing of quartz on each side, also two quartz stringers near the center, holding the same course as the vein. Parallel to the slates, and running between them, are four strata, locally called crossings, apparently an altered condition of the slate; these are cut off by the quartz vein. The vein is traversed by small seams, which, when closely examined, show small crystals of sulphurets and sometimes gold. These are the gold seams of the pocket miner, and run at right angles with and through the crossings; these he carefully follows to the vein, when, if it is at all gold-bearing, it will make a pocket on the contact. These pockets appear to have a solid gold nucleus, surrounded by concentric rings impregnated with gold in a greater or less area. The above figure,

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At this depth flowing water was struck. The water flowed from the casing at the height of 34 inches above the ground.

WATER AND NATURAL GAS IN THE VALLEY LANDS OF YUBA COUNTY.

Between Marysville and the northern boundary of the county, throughout districts lying on the western side of the railroad, and extending for several miles to the eastward therefrom, except where spurs run down from the hills into the valley, an abundant supply of water can be obtained at a depth of from 10 to 12 feet. The formation is about as follows:

Sandy loam..

Hardpan, sometimes absent

Gravel, with a good supply of water.

2 to 20 feet. 2 to 10 feet.

Wells through these districts are usually bored to the depth of from 20 to 30 feet, but the water stands at a depth of about 10 feet. Toward the eastern hills the water lies deeper, and in boring difficulty is encountered from bowlders; most of the wells are dug. Water is also flumed from springs in the hills.

The city of Marysville is supplied from two 12-inch wells, one bored in 1850 being 80 feet in depth, and one bored in 1872 being 180 feet deep. During the summer more than 1,000,000 gallons of water is supplied from these wells every twenty-four hours, and during the winter about 300,000 gallons.

At the Buckeye Mill, in Marysville, a well was bored in 1888 to a depth of 218 feet, and the following formation was observed:

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The well-borers state that the principal supply of water came from the coarse sand and gravel at a depth of 153 feet. After pumping with a steam pump the water stood at the height of 4 feet from the top of the well.

South from Marysville, following the railroad, water is very abundant, and the formation is very similar to that observed to the north of the town.

At Colema, between Marysville and Reed's Station, an orange and olive orchard and vineyard of about 225 acres are irrigated by pumping from bored wells that are about 50 feet in depth, the water rising to within

10 or 12 feet of the surface. It is said that more than 500 gallons per minute have been pumped from these wells for several consecutive days without appreciably lowering the water; but when 1,000 gallons per minute were pumped it lowered the water about 4 feet.

IRRIGATION.

Irrigation in Yuba County is represented by the Brown's Valley and the Excelsior Irrigation Districts.

The Brown's Valley Irrigation District, which was organized under the Wright Act, diverts water from the North Yuba River, about 3 miles west of San Juan, in Sierra County. The district comprises some 43,000 acres, lying between the main Yuba and Honcut Creek. The water is brought by canal and flume a distance of 28 miles, to high land on the eastern side of Dry Creek, about 8 miles northeast from Brown's Valley. At this point the water is dropped down a ravine a vertical distance of about 300 feet; thence it is taken through a pipe across a suspension bridge to the western side of the creek, and distributed throughout the irrigation district. It is estimated that the main ditch will carry about 5,000 miner's inches of water.

HYDRAULIC EJECTORS.

By E. A. WILTSEE, E.M.

This ingenious device for the elevation of small quantities of water without the aid of pumping machinery has found quite a widespread application among the drift gravel mines of Nevada City, Nevada County, where the quantity of water is small, and water power under high head easily procurable. The contrivance depends upon the principle of induced currents for the raising of the water into the pressure stream immediately in front of the nozzle; once there, it is elevated to the surface simply by the force and velocity of the larger stream of power water, which makes the ascent of the discharge pipe under the influence of its heavy head.

The arrangement of the machine, if such it can be termed, is quite simple, and is shown in the accompanying sketch. The component parts are: The pressure pipe from surface, down which the power stream is conveyed; an ordinary "tee," into which the power water discharges through an internal nozzle, to be received in an internal receiving nozzle of slightly larger diameter an inch or two away. Into the branch arm of the "tee" the suction pipe from the sump is fitted, so as to deliver the water, induced by the vacuum formed, into the pressure stream between the "tee" nozzles; and lastly, the discharge pipe to surface, a little larger in diameter than the power pipe conducting the pressure stream down.

The construction of the nozzles is very simple. The fitting entering the "tee" is a nipple, to which the pressure pipe is attached externally by a coupling. On the inside of the nipple is riveted a blunt nozzle with the necessary aperture, as shown in sketch. The receiving nozzle is of the same description, but a little larger in diameter, and riveted into the end of the nipple entering the other end of the "tee" and to which the discharge pipe is coupled. The nozzles are thus adjustable within a certain distance by means of the nipples, and in small machines this has been found ample. The construction of the nozzle is shown in the sketch. The size of the nozzles used on these small arrangements is usually three eighths of an inch in diameter for the pressure nozzle, and five eighths of an inch for the receiving nozzle. This proportion does not seem to be absolute, the requirements of the contrivance being that the receiving nozzle shall be large enough to receive the pressure stream and the added water to be elevated, and near enough to the pressure nozzle to collect and receive the stream before it breaks and scatters. A valve should always be placed in the power pipe near the "tee," in order to turn off the power water in case of any accident to any part of the apparatus; it would also be advisable to have a large valve in the discharge pipe near the device, if the discharge were of any considerable size and contained any large quantity of water.

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Three arrangements of the device are shown in the sketch, not because all are deemed advisable, but as representing the three types found in actual use.

No. 1.-That used in the Odin Mine; is the worst of the three, and is considered by the writer an example of "what not to do." In this arrangement the power stream, after entering the receiving nozzle and having the additional stream to be elevated, is forced around two right angle turns, and necessarily loses a large proportion of its velocity, power, and working force.

No. 2.-In use at the National Mine, and the original device of the inventor, or designer, is to the mind of the writer by far the best mechanical device. The full power stream is led around the turns before its discharge from the nozzle, and the discharge, when it does take place through the reduced nozzle, is straight up in the direction in which its work is, with no impediment or obstacle in its path, except the natural friction of the straight pipe.

No. 3.-The arrangement in use at the Manzanita Mine; while not so bad as No. 1, would seem to impair the force of the working stream to some extent by reason of the heavy friction entailed by leading the stream around the bend preparatory to its upward flight. As the design has been used but a short time, though with great success in every case, it was impossible to get any exact figure as to the amount of work done, or percentage of power realized from the working stream. As nearly as the operators of the device could state, about one quarter to one third of the number of inches of water employed in the power stream were raised from the water of the mine. In other words, a power stream of 4 miner's inches would elevate with it 1 miner's inches from the mine. It is to be hoped that the users of this arrangement will carefully measure both streams and ascertain the exact amount.

The power water was employed under various heads, varying from 600 feet in the Odin Mine to 200 feet in the National Mine. The water was elevated 180 feet in the Odin Mine, 210 feet in the Yosemite Mine, and 100 feet in the National Mine. As the power water is delivered at the bottom of the shaft or workings, the working head will always be increased by the vertical distance from the surface, in addition to the head of power water at that point.

The nozzles are placed, in these small arrangements, at distances of from 1 to 2 inches apart. The adjustment is made by trial after the device has been put together. The designer of this form of hydraulic ejectors is Mr. Rounder, of the National Mine, and to him is due the credit of the application of the principles involved.

The application of the device, while somewhat limited, is of considerable importance. By its use all heavy expense for pump columns and attendant machinery is saved-no small item in prospecting operations. While it has not as yet been tried here on a large scale, to the knowledge of the writer, it is certain the operation would be successful, the only question being as to whether its operation would be economical, on account of the small percentage of the power realized. Where water power is free this item would not enter into consideration; but when the quantity of water to be raised is small, and the distance to be elevated not too great, and when water power can be obtained under heavy head

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