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feet wide by four deep, with a large fall, will be needed by the miners above Nevada. Of course it will be the aim of the proprietors to dispose of their water to the nearest buyers, as the further they carry it, the greater their loss by leakage and evaporation.

In view of these facts, it behooves the citizens of Grass Valley to make some other arrangements to secure the needed supply. We have heard a number of projects mooted, but nothing seems to be done beyond talking about it. Will not some one make a determined move in the matter. We have men among us whose property and business would be doubled in value by the introduction into our town of a plentiful supply of water. We have surveyors and engineers who are abundantly able and competent to make the preliminary surveys, and to carry on the work to a successful issue. Will not our property men take hold of the matter? If an early move is made, water can be obtained; if we delay much longer, the water which at the present time is free will be diverted to other channels, and the opportunities which are now presented will be lost for ever, at least to the present generation. Again we ask who will move in the matter? We pause for a reply.

AN EXTENSIVE FLUME. An extensive Flume.—Mr. A. S. Hart & Co. have purchased the river claim in front of the town of Oroville, Butte Co., and are about to commence turning the river at a point nearly opposite the Orleans Hotel. The flume will be thirty-five feet wide, six feet deep, and three thousand feet longprobably the most extensive in the State.

KENT'S APPARATUS FOR SEPARATING GOLD. Patented in the United States, Great Britain, France and Belgium. Shortly after entering upon my official duties as Melter and Refiner in the United States Assay Office, it was my ambition to discover a more effectual method for separating gold and silver from foreign substances than any which had been hitherto employed. Having an abundant and constant supply of material, I had facilities for effecting this object, which enabled me to investigate the subject in the most thorough and practical manner. The result of this investigation was the invention of the apparatus herein described, the first of which has been constantly in use at the United States Assay Office in New York, since August 1st, 1855. One of them has been subsequently introduced into the United States Mint at Philadelphia, where it has been in daily use since April 1st, 1856.

The most striking peculiarity of this invention is, that so large a proportion of the gold can be separated by specific gravity alone. During the first six months of its use 9,333.66 ounces of gold and silver were separated by it, and of this large amount, 9,110,66 ounces (which is 97.6 per cent, of the whole) were obtained from the “Separator,” which is that portion of the apparatus in which the separation is effected by specific gravity in a high column of water, without the use of mercury. The specific gravity of quartz is 24, iron pyrites 5, and of gold nearly 20. The finest particles of the precious metal are, therefore, nearly eight times heavier than those of quartz, and four tin heavier than those of iron pyrites. Consequently when these, or other substances containing gold, are suspended in a high column of water, the gold which is the heaviest, falls to the bottom, and with a gentle current of water passing through the apparatus, the earthy substances, which are lighter, and the sulphurets, when re-crushed sufficiently fine, are carried away, and the gold remains.

Although gold is nearly twenty times heavier than water, it will sometimes float upon the latter, and is then called "floating gold." This is due to a repulsion of the fine particles of gold and water, which temporarily overcomes

VOL. VII.-7

the law of specific gravity; but it occurs only when the gold is dry ou the surface. If a needle be wiped dry and placed lightly on the surface of water, this also will float, and become a floating needle ;' but let the fine particles of gold or the needle, become once wet, they will each obey the law of specific gravity, and fall to the bottom.

The principles involved in the action of the “Gold Separator" are based upon the theory described above. The ore (which has been previously crushed as fine as possible) is first agitated with water, by feeding it into the hopper or “Grain Separator,” in which the gold which has been liberated by the previous crushing, is separated and retained. The earthy portion of the crushed ore is carried thence into the centre of the column of water in the submerged Chilian mill, in such a manner as to prevent the finest particles from floating upon the surface of the water, in which, as in the case above mentioned, the gold is separated and falls to the bottom, in obedience to the law of specific gravity. The heavier particles of earth or ore, which are those containing gold, also fall to the bottom of the mill, by virtue of their specific gravity, where they are ground under the water in which the finer portion is suspended by the agitation of the wheels, the gold falling to and remaining at the bottoin, while the earth is carried away by the current of water; and as daily practical operation has proved nearly 98 per cent. of all the gold is thus saved by specific gravity alone, and without the use of mercury, by the “Gold Separator" above described.

The principles involved in the action of the “ Amalgamator” are based upon the following theory :-It is well known that gold, when clean, readily ainalgamates with mercury: but if the particles of gold, or the surface of the mercury, are dirty, there is a repulsion of the particles similar to that above mentioned, in the case of floating gold, and consequently dirty gold, such as is found in all native ores, and particularly in auriferous pyrites, cannot be entirely separated by amalgamation alone. Every gold miner will bear evidence to this. But dirty gold is nearly as heavy as clean gold, and consequently it can be separated by specific gravity upon the principles above mentioned ; and when the particles of gold thus separated, and the surface of the mercury are both cleaned, as in this apparatus by the double action of wooden paddle wheels, the final separation of the gold may then be effected by amalgamation.

It is also well known to gold miners that when the mercury used for amalgamation is broken up, or divided into small globules, these cannot be made to reunite when dirty; and consequently a large quantity of mercury as well as gold is lost, in most of the amalgamators heretofore invented. With the apparatus herein described, this is not the case. The mercury is not agitated or broken up by stirring, and the high column of water above it prevents it from being carried away by the sand, consequently the mercury is saved in the same manner as in the separation or saving of gold by specific gravity. After six months daily and constant use of this amalgamator, no diminution of the quantity of mercury originally used was observed; and by carefully rewashing five barrels of tailings which had previously passed through it, only a trace of mercury was obtained.

It will be observed, that the earthy substance or crushed ore, when once supplied to this apparatus, is subjected to three separate, distinct and successive operations, all of which are based on scientific principles, and applied to the metallurgy of gold in the following manner :

1. The crushed ore is first supplied to the hopper or grain separator, in which it is agitated with water, and subjected to an operation which verr nearly resembles hand-washing or panning, which is familiar to all gold miners; but it is much more perfect than hand-washing, and instead of being performed. by hand, is effected by the aid of machinery, so as to avoid manual labor, and perform a much larger amount of work. By this operation alone, all the gold that can be saved by hand-washing or “panning," is separated at once, without abrasion or loss.

2. The earthy portion, from which all the gold which can be separated by panping, is now removed, passes into the centre of the column of water in the submerged Chilian mill, where it is re-crushed under water, so as to liberate the finer particles of gold from the earth, and the whole being suspended in the high column of water, by the agitation of the wheels, the earthy portion passes off when ground sufficiently fine, while the gold falls to the bottom of the mill, by virtue of its greater specific gravity, and is saved in the form of very rich or highly concentrated ore, from which the gold may then be profitably separated by smelting.

3. The fine earth which passes from the mill is again suspended in another column of water, and the finest particles of dirty gold which are thus separated by specific gravity, are cleaned by the double action of the paddlewheels, and then collected by amalgamation with the mercury, which is also cleaned at the same time, in such a manner as to prevent loss of mercury or the gold

This apparatus is not heavy enough for crushing quartz, and was not designed for that purpose. But it is particularly adapted for separating gold from the sulphurets, and this is the portion usually lost by the use of other apparatus. For these reasons, the crude ore should be previously crushed as fine as possible, by larger and more powerful apparatus ; then concentrated in such a manner as to leave the sulphurets and wash away the quartz. The sulphurets which retain the precious metal are then to be supplied to this apparatus for separating the gold. By this process a large amount of ore or tailings may be worked daily, because the bulk of the rich sulphurets is small, compared with that of the quartz. If, therefore, twenty tons of the powdered ore, or tailings from other apparatus, contain but one or two tons of sulphurets, the gold from twenty tons of it may be daily saved by this invention,

MONSTER NUGGETS FOUND IN VICTORIA,

1. A pure nugget weighing 336 oz., called the Dascombe Nugget, from Bendigo. This nugget was shown to Her Majesty by Messrs. Herring, of London, to whom it was sent by Mr. Joseph Herring, gold broker, Melbourne. - May 31, 1852.

2. A pure nugget, weighing 340 oz., from Bendigo.--Sept. 18, 1852.

3. Monster nugget, or bar (from its shape), of gold, dug up within ten yards of where No. 1 was found, weighing 564 oz. The fortunate finders were from Adelaide. It was about 2 ft. long and 5 in. broad, entirely free from quartz, and shaped somewhat like a twisted or French loat.—Oct. 16, 1852.

4. A lump of gold and quartz, weighing 1620 oz., found at Ballarat; was taken home in the steamer Sarah Sands by the finders, who came out in the Great Britain about ten weeks previously.-Feb. 5, 1853.

5. An 84 lbs. or 1008 oz. nugget, found at Fryer's Creek; shipped per Lightning in April, 1855.—April 7, 1855.

6. Nugget weighing 40 lbs. or 480 oz., found at Ballarat; shipped in Red Jacket, May, 1855.—April 7, 1855.

7. Nugget weighing 48 lbs. or 576 oz. found at Ballarat and shipped in Red Jacket, May, 1855.-April 28, 1855.

8. Splendid quartz specimen, weighing 24 lbs. or 288 oz. from Mount Blackwood; shipped in the Red Jacket, May, 1855.—April 28, 1855. 9. A nugget, weighing 88 lbs. 4 oz. or 1060 oz., found at Maryboro'

, or Simson's Ranges. This was melted into ingots, and turned out a losing speculation for the purchasers.—June 23, 1855.

10. A nugget, weighing 760 ozs., found near Old Daisy Hill; still in Melbourne.-Oct. 27, 1855.

JOURNAL OF COPPER MINING OPERATIONS.

LAKE SUPERIOR REGION. The reports from the Lake Superior Region are generally of the most favor. able character. The position of many of the mines is such that their intrinsic value will be more positively demonstrated this year than ever before. From recent numbers of the Lake Superior Journal and other sources we obtain the following facts:

The increased facilities for obtaining supplies, shipping the copper, and the experience already attained in “mining" are rapidly establishing this business upon the same basis of certainty which characterizes manufacturing and other pursuits. It is a business which requires experience and thorough investigation to be calculated with certainty.

This position is gradually being attained from year to year, as the mines are opened and developed, and the day is not far distant, when mining operations will be looked upon in the same light as mercantile or commercial business, and attended with no more risk or uncertainty than these. Experience will teach the miners how and where to expend their labor most profitably, and thus avoid all unnecessary expenditure, which now consumes the product, and sometimes more, of the mines. These facts in connection with the good reports from the mines leave no room for doubt as to the final issue.

The Central Mine will ship about 40 tons of copper this season, which, as their expenses are not heavy at the present time, will somewhat more than pay the current expenses of the mine. In the estimation of persons of competent judgment, the prospects of this mine are very flattering, and should present appearances continue, the stock of this Company will pay good dividends ere long.

The Isle Royal raised and shipped 203 tons during the nine months preceding August 1st, but the amount raised during June and July was something less than the estimates and expectation.

The Rockland is in the ascendant, and it is confidently expected that it will equal the Minnesota in a comparatively short time. Our latest report from the Garden City are of the most encouraging character, the “ash-bed" yielding richly in stamp work. We understand that on account of some legal ditficulty, the operations at the Ohio location have been suspended, although the show of copper is excellent.

We learn from a gentleman just from the North American mine that it is doing remarkably well, having reached the “paying point." There are now employed at this mine 180 men, 96 of whom are miners, who are now getting out about 30 tons a month of stamp work and masses. They have shipped since the 1st of January last, 579 tons, and expect to ship in all the present season 324 tons. The same gentleman informs us that the Cliff continues to work well, and will probably ship 1500 tons this year.

At the Mass Mine they have lately uncovered a lode lying to the north of their main vein which shows remarkably well for regularity, and which we regard as a new feature of great value to the location.

We gather from the “ Report of Chas. T. Harvey, Esq.," the following facts in relation to the Norwich Mine.

The first object of interest in proceeding to the Mines are “road facilities."

In preceding years a road had been constructed from the Mine to the Ontonagon River at a point called the American Landing, distance ten and one-balf miles, at a cost to your company, including a joint interest in the Landing Dock Warehouse, &c., of some $6,500. But little outlay is required (this sea

son) to keep it in suitable repair for the land carriage of copper and supplies which are transported from Ontonagon to the Landing in flat-boats, a distance of some twelve miles.

On arriving at the mine, the first features noticed were the "Surface Improvements.” Unfortunately the Company lost the stamp-house and saw-mill by fire, on the 13th of April last, caused by a spark from the engine chimney igniting the roof.

It seemed evident from a view of the premises that it was expedient to rebuild the stamps without delay; and on receipt of advices from the Board on the subject, the Superintendent took energetic measures to replace them in the shortest time; and they will be ready for use about the first of September, probably. The engine boilers and most of the iron shafting, &c., of the old stamps will be re-used in the new, having received but little injury. Besides this building notice was taken of the appropriate dwelling house for the agent, a good log-house for boarding the miners; a convenient barn, kiln-house shops, store-houses, &c.

The interior of the mine was next very closely examined. The general plan for its extension has, of course, been adopted in former years, and is now in the main adhered to; but at present good ventilation is secured in the main sections of the mine, and the vein approached so far in advance of its removal by “stoping," by means of adits, shafts and levels, that the miners can now be kept more in productive work” than at any previous season since its commencement. This was not the case, but precisely the reverse during the past year, owing to the special efforts made to realize copper during the crisis in mining affairs in the winter of 1854–5. This circumstance shonld be borne in mind in contemplating the reduced products of the mine in 1855, and is a strong reason to hope better things for 1856.

The Norwich Mine has been worked up to this time without any other than horse elevating power-longer probably than any other of the same promises on the mineral range.

The lower level of the mine is 140 feet below the adit, and 350 feet below the present horse power, and the necessity for steam power is now imperative. With the approbation of the undersigned, Mr. Davis, superintendent, concluded to purchase a twenty-five horse power engine and boilers, newly made, then for sale at Ontonagon, and costing, with the gearing for a saw-mill, about $3,000. This will, it is believed, be in operation at the mine by the middle of August, at a cost of some $4,000, and will be all the steam power required until the mine shall have doubled or trebled its product. The constructive features of the adits, levels and shafts are in the main good; and from the inspection of all the prominent mines, it can be asserted, that for convenience and economy of the mineral obtained froin the mine, in kilns, stamps, &c., the arrangement and position of the Norwich mine is not surpassed by any in the Lake Superior District.

The mine produced from 1846 to 1861
During 1852 to April 1st

1853
1854
1855
1856 to April 1st

Tong.

1 12 47 18 189 108

Lbe. 1,800

200 876 881

857 1,200

The product for the month of April, 1856, was 12 tons of masses, besides the stamp-work after loss of stamp-house.

The stamps' product per month, Mr. Davis, "from reliable data,” estimates at 4 tons per month for the last three months.

It may be remarked in reference to the above figures, that in 1854 only 20 miners were at work on an average, as this mine was crippled for supplies and means. In 1855, during the panic in mining affairs, the mine was worked with a view of getting out the greatest possible quantity of copper in the shortest time, and at the least expense practicable, hence good policy re

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