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By J. D. Audley Smith

Heine's " blue test" for copper, as described by the authorities generally, calls for a set of standard colors; and there has been some discussion concerning the relative superiority, for this purpose, of sulphate and nitrate solutions. The whole matter evidently hinges on the preservation of the standard colors in well-stoppered bottles. The apparatus described by Q. L. Heath* cannot be much improved, when very accurate readings are required. The following method was devised for the purpose of doing away with preserved sets of standard colors, by making a fresh standard for each batch of assays. The solutions are prepared in the usual way, each ammoniacal solution being filtered into its separate bottle, and then filled up to the containing-mark and thoroughly mixed. A similar color-bottle, with an " S " etched upon it, to distinguish it from the other bottles, which are numbered to correspond with the samples, is kept to run the standard. About 150 C.C. of water is put into it, and then the amount of acid (sulphuric or nitric) present in each determination, followed by 30 C.C. of ammonia (s. g. 0.90), which should make the mixture strongly ammoniacal. The liquid is now made up almost to the containing-mark (200 c.c.), say within 1 C.C. The lowest assay is selected first and placed alongside the standard, which, at the beginning, contains no copper. A copper-solution is then dropped into the standard from a burette ; and after each addition the bottle is well shaken and compared with the assay-sample. This operation is repeated until the two shades match exactly, when the burette is read and the assay-result is calculated. The assay next in order of depth of color is now taken and treated in the same way, and so on, until the batch is completed. It

Jan 1, 1901

Jan 1, 1901

By H. M. Chance

Probably no other prosperous mining district is so little known as the Black Hills. The name leads one to assume that the district is a rolling country, consisting of more or less insignificant hills. Nothing could be more untrue, as the Black Hills is an elevated region rising to heights of 7000 and 8000 feet above sea-level, and broken by deep gorges and ravines. It is, in fact, a mountainous country in all that that term implies ; but the cañons and gorges are of such a character that the country is easily penetrated by railroad-lines, and good wdgon-roads exist to-day, affording access to every portion of it. Aside from the stampede to the Black Hills country in 1876, when gold-placers were discovered, and 15,000 or 20,000 people became infected with the mining fever, the region has never had a mining " boom." Quartz-mining commenced in 1877 or 1878, and has been successfully prosecuted ever since; the output of gold steadily growing, until at present the yield is about $7,000,000 annually. This great production is about equally divided between two entirely different classes of deposits. The first class, comprising the so-called quartz or free-milling ores (of which the Homestake mine is the principal producer), are veins of generally steep dip, in the older metamorphosed rocks, and similar to the veins worked in other mining districts. The second class of mines is located in what is known as the " siliceous gold-belt." The Siliceous Gold-Belt. This belt, more particularly to be described in this paper, lies in the immediate vicinity of Deadwood and Lead City, and covers an area 6 or 7 miles in length by 3 or 4 miles in width. The formation in which the siliceous ores are found is a nearly horizontal series of sandstones and shales, generally

Jan 1, 1901

As it is my opinion that deep alluvial mining in Victoria and in the Murray Flats in New South Wales is practically in its infancy, and considering that we, the old school of alluvial miners, who have thirty or forty years' experience to guide us, must in the natural order of things hand over the management of our mine, to the younger and less experienced' generation of miners, I thought that as our Association has been formed for the purpose of disseminating information and the exchange of ideas, a few notes on the practical working of alluvial mines might be of some service to aspirants for the position of mining manager.The greatest difficulty the alluvial miner has to contend against is the immense quantity of water contained in the drifts overlying the wash in the gutters or ancient river beds, and to cope with this water successfully and economically is the point to be aimed at by our mining managers; and if they thoroughly understand this part of their business in all its details, they will not only win kudos for themselves, but will be the means of saving large sums of money to the companies they represent, and, in many instances, will make a success of a venture which otherwise might be stopped for want of funds before it is properly proved. At the present time, although we have had over forty years' experience indraining the deep leads of the colony, I regret to say that a large amount of ignorance still prevails amongst both directors and managers.

Jan 1, 1901

By Charles Catlett

Probably no one has had occasion to examine an undeveloped coal property without hearing some hopeful or interested party insist that the bed will improve when opened some distance under cover. When the bed is already in good condition, the opinion is usually advanced that the same character may be expected, at least to the bounds of the hopeful individual's holdings. My attention has been called in this way to the extent to which a bed is affected by its outcrop at the surface ; and having had opportunity to examine a number of openings immediately at the surface, and also a short distance under cover, I submit some observations bearing on this question. Whatever may have been the original variations, we may assume that coal-basins presented in comparatively modern times approximately parallel beds interstratified with fire-clay, slate, sandstone, etc., as represented by Fig. 1. Under the effect of erosion, Fig. 2 would be formed. It is obvious that along the line A, B, C, in Fig. 1, the beds exist under conditions differing from those at A', B', C', or again at A", B", C", in Fig. 2, in their exposures to atmospheric agencies, pressure and erosion. The effect of the first is to decompose and soften many of the strata; of the second, when presented unequally, to cause the movement of such material as was at all plastic towards the point of least pressure ; and of the third, to remove the strata in whole or in part. It

Jan 1, 1901

Amongst the unavoidable studies of the mining engineer who desires to reach the maximum efficiency, is the subject of patents. With the fundamental principles of the patent laws of this and other leading countries he should of course befamiliar, but still more should he keep abreast of that practical knowledge which will enable him to act or advise wisely when the patenting of a new invention, or the sale, purchasing, or adoption of a new patented machine or process becomes amatter for consideration. As every engineer worthy of the name is an inventor and more particularly every mining engineer he has a direct interest in watching the progress of legislation and administration concerning patent monopolies.His worldly prospects may indeed, to a considerable extent, depend upon the defeat of bad patent laws and the removal of incompetent officials, or the appointment of better ones. Better patent administration is always in Australia a valid requirement, and until engineers generally take up and press the demand, bad administration is likely to continue. Even though every engineer is not a patentee, nevertheless his interests in patents must always be direct and powerful, and ignorance or apathy in regard thereto must inevitably injure either his own interests or those of his employer. When we consider the tens of thousands of mines scattered through Australia alone, on everyone of which there is expensivepatented machinery, and when we consider the thousands of...

Jan 1, 1901

By C. S. Herzig

Some time ago, in Mexico, our signal-bells in a 700-foot shaft caused us considerable annoyance by continually getting out of order, each time so delaying our hoisting operations that we naturally desired to remedy this evil. There were two mays open: either to patch up the old bell, which was of the ordinary pattern, every time it failed to work, or else to devise some new arrangement.. On consultation with our foreman we designed a signal-device which, during the number of months I watched its operation, worked satisfactorily, without once getting out of order. We sought to produce a simple device, in which no greater pull on the lever would be necessary from one level than from another; to counterbalance independently the weight of the pendant bell-rope, so that there would be no direct weight on the working-parts of the bell itself, and likewise to arrange it so as to necessitate only a light pull on the lever in signaling; and, finally, to make some sort of trip-arrangement, so that whenever the signaling-lever underground passed through a certain arc the signal would be given in the engine-room. By this means we wished to obviate the ill effects of sudden heavy pulls and rough usage in general, such as all signaling

Jan 1, 1901

By T. Guilford Smith

In presenting the subject of " Armored Turrets for Coast Defense " to this Institute, I am indebted to the Gruson Ironworks, a company incorporated under the laws of the State of New York, for valuable information, model and plans, by which I hope to make clear the construction and peculiar merits of this class of gun-protection. I wish it understood, however, that this is not an undeveloped and untried inventor's ideal, but an advanced and fully perfected system, which has long since passed the experimental stage and has been adopted by most of the foreign governments, after years of extensive experimenting and the expenditure of millions of dollars. The present seems an appropriate time to present the matter to the scientific public, since, for the first time, it is possible to produce these turrets in this country, of American material, and made by American workmen, owing to an agreement entered into between the Gruson Iron-works and the Fried. Krupp Grusonwerk, of Magdeburg-Buckau, Germany, where they have hitherto alone been manufactured. Although its full development and present perfection have been attained at the German works, it may be of historic interest to state that the first idea of using a rotating protected platform for large guns originated with Mr. Theo. Ruggles Timby, a native of the State of New York, who filed a caveat in 1843 for a " metallic revolving fort, to be used on land or water, and to be revolved by propelling engines located within the same and acting upon suitable mechanism." This was followed in 1862 by the issuance to Mr. Timby of two patents (No. 35,846 and No. 36,593) covering the ideas described in his caveat of 1843. The first practical application of this system was made on the " Monitor," of Civil War fame, Mr. Timby receiving $10,000 for two

Jan 1, 1901

By F. L. Ransome

The dike here described is exposed in the workings of the Wedge and Bachelor mines, on the southern side of Red Canon, north of the town of Ouray, Colorado. Its course is north 80° east, or nearly east and west, and it hades to the north about 10°. It rarely outcrops, and was nowhere seen at the surface near the mines. A specimen collected by Dr. A. C. Spencer about two miles to the westward, near the mouth of Red Creek, indicates, however, a probable exposure of the dike near this point. The Wedge and Bachelor mines lie in a nearly horizontal series of fine-grained, light-grey sandstones, alternating with beds of very fine-grained shale of the same color. The shale as encountered underground is unusually compact and massive, but weathers readily on exposure, and splits much after the manner of ordinary shale. When fresh it closely resembles some finely arenaceous limestones, but it does not effervesce with acids, and is eseentially a fine, indurated, siliceous silt. Near the surface, and near the top of the sedimentary series as

Jan 1, 1901

The rapid advance in the adaptation of scientific knowledge to the treatment of ores, resulting in improved chemical and metallurgical processes, has enormously increased the possibility of working lodes profitably, which a few years ago were passed over as unpayable. By the discovery of chlorination, and later of "Cyanidation," by the highly improved methods of concentration, and by the rapid advance in our knowledge of smelting (for which we are greatly indebted to Americanmetallurgists), and by the gradual replacement of scientifing principles and enlightened management, for rule-of-thumb methods formerly in vogue, many large low grade bodies have been opened, and are now paying dividends, which were,twenty years ago, looked upon as hopelessly unpayable. It has been more especially in these large low grade ore bodies, that modern methods have been benefical; for small lodes must be rich to pay at all, as they cannot be worked on the same gigantic scale, but even in these a percentage of metal is saved which formerly was absolutely lost.To make these large deposits remunerative it is, however necessary to try and find the point of greatest economic advantage, to handle the ore in vast quantities, to erect huge plats to treat it, to substitute automatic appliances for hand labour as far as possible, and to combine several processes supplementary to one another, so that ore which is not amenable to one process, shall be saved, by another; and by doing...

Jan 1, 1901

By Thomas Haight Leggett

I.—The Deep-Level Shafts. The gold-deposits of the Witwatersrand (Anglice, " White Waters' Range ") are, as is well-known, more or less parallel and tilted sedimentary beds of quartz-pebble conglomerate impregnated with gold. These beds, however, are locally called "reefs"—a term equivalent in signification to the American "ledge"—and, like the latter, usually applied to lodes, though covering in practical usage all deposits of tabular form. The first developments of the reefs of the Rand were naturally made along their outcrops. Since the mining law of the Transvaal does not confer upon locators the "extralateral right," the property of each locator upon the outcrop or apex ends with the vertical planes drawn through the boundaries of the claim. Consequently those portions of the reefs which lie "on the dip," beyond these boundaries, are separately acquired by locating new surface-claims, and are usually to be mined only by means of vertical shafts, reaching the reefs at considerable depths. The term "deep-level properties " is given to such claims on the dip, and the " deep-level shafts " are the vertical shafts sunk in the hanging-wall of the Witwatersrand reefs, in contradistinction to the incline-shafts almost universally employed on the outcrop-properties. Number and Distribution.—The accompanying diagram, Plate I., shows the number and depth of these deeplevel shafts, completed or under process of sinking, up to January 1, 1900. A number of shafts already located upon new deep-level properties, but upon which no work has yet been done, are not included in this diagram.* Vertical shafts sunk upon outcrop-

Jan 1, 1901

Jan 1, 1901

A good deal of experimental work has been done from time to time on the application of compressed air to the elevation of wet pulp. On account of the flat nature of most of our mill sites elevation of the pulp has to be provided for, and the various methods in vogue show considerable loss of time, in the replaceing of wearing parts. During the last two years the writer has carried out a great many experiments with a view of devising an elevator that will give continuous work with a minimum of wear.The results do not show a high efficiency for the power employed, but the lift is continuous in operation, very cheaply installed, and possesses no wearing parts. The lift was tried working in a bore hole of 8 in. diameter, but in many cases it is more convenient to sink a small well for the purpose. The result to date showed that the most efficiency was obtained when the depth of the wellwas not less than the height of the lift required. The pressure of air required in pounds per square inch was (approximately) half the number of feet to be lifted.In the majority of cases the lift required varied between 20 ft. and 50 ft. and the air pressure required between 10 lbs. and 25 lhs. per square inch. In most existing installations the air compressors in use were delivering air to the receivers at about four times that pressure, and when air so compressed was expanded to perform its work at a reduced pressure, it was apparent that the power exerted in origInally compressing the air above the working pressure required at the lift was absolutely lost.

Jan 1, 1901

That gold will dissolve in sodium hyposlphite solutions is known from the lixiviation of silver and gold ores.The gold will dissolve only in small quantities. According to Stetefeldt, if gold leaf is treated for a time with sodium hyposlllphite solutions of varying strengths solution takes place in every instance, the deviation in quantity being very slight.In order to form hyposulphite double-salts, the gold must become oxidised, the oxygen being derived from the air absorbed by the solution. Consequently, it is the quantity of free oxygen in the solution by, which the reaction is determined, as for one equivalent of gold dissolved one equivalent of caustic soda is set free.

Jan 1, 1901

By Walter Harvey Weed

Introductory.............449 Summary oF Types............452 I. The Virgilina Type...........452 The Virgilina mines...........452 Location.............452 History.............453 The rocks of the district..........453 The veins.............454 Notes on the mines.... 458 The Holloway. 458; Yancey and Durgy. 465 ; Copper World. 467 ; Frazier. 467 ; Thomas. 467 ; Anaconda. 468; Blue Wing. 468; High Hill. 472; Dorothy.......474 II. The Gold Hill Type...........474 The Gold Hill mine...........475 Location.............475 History............• 475 Surface improvements.......... 476 The rocks............478 Vein.phenomena...........478 Character of the ore..........481 Origin of the ore...........481 Notes on the mine.workings.........482 Other occurrences of ore-deposits of the Gold Hill type.. .. 483 III. The Ducktown Type..........484 The Ducktown mines...........485 Other examples of the Ducktown type....... 494 Alabama mines...........494 North Carolina examples : Ore Knob.......496 Virginia examples..........497 IV. The Catoctin Type.. ......... 498 General characteristics,......... 498 The Linden district...........499 General distribution of the Catoctin type.......503 Introductory. In the early history of this country the existence of copper in the Appalachian region was well known. but no mining mas attempted until the discovery of the Ducktown deposits in

Jan 1, 1901

By David T. Day

In the summer of 1898, a demand suddenly arose for commercial quantities of the element osmium. At least half a ton was wanted for the manufacture of a new incandescent light. This led the writer to examine localities where platinum had been reported, in order to determine whether osmiridium mas contained in the crude platinum. With the co-operation of the concern most interested, the Welsbach Light Company, and in company with its President, Col. William E. Barrows, I visited most of the leading American localities where platinum has been obtained. I also wrote to every available placer-mine in the West for samples of the heaviest sands, in order to test them for platinum. The results of this inquiry are given in the present paper. Distribution. The notices of the occurrence of platinum in this country given in scientific journals include two interesting observa tions in the East. One concerns a nugget described by Peter Collier of Washington, D. C.,* and said to have been found on land adjacent to the village of Plattsburgh, N. Y., which weighed 104.4 grammes, and contained sufficient chromite to reduce the specific gravity from 17.35 for the heaviest portion to

Jan 1, 1901

By C. S. Herzig

In the Engineering and Mining Journal of Jan. 27, 1900, there appeared an article by Fred T. Greene, describing a method of measuring stopes by the use of strings, a clinometer and a tape. In the early part of 1899 I had occasion to use a somewhat similar method, for the purpose of accurately ascertaining the volume of a very irregular drift connecting two mines. This drift was an important factor in a lawsuit for $150,000, in which it was necessary to determine accurately the volume originally occupied by the material extracted from the drift. While it is unnecessary to give all details of the controversy, some explanation of the conditions is required for a clear understanding of the following description. This drift was started by the a E." Co. from its workings, in about 7 ft. of ore, and headed toward the " G " property, the plan being to extract all the ore between foot- and hanging-walls, but to take out nothing but ore. As the " G." workings were approached; the ore-body became very irregular and much thinner. It was, however, very closely followed, and where the drift broke through into the " G." workings, the hole was only 11 inches high by 14 inches wide, or just about the size of a man-hole in a boiler.. Thus, this connection-drift tapered sharply; and the very irregular foot-wall sloped toward the " G." workings, and entered them at a place where the stope was only about 3 ft. high, and the ground had already commenced to cave. It may be added that the ore-body was a nearly flat deposit of lead carbonate in limestone, the ore and gangue being quite soft. I was called upon by the " G." people to make the survey

Jan 1, 1901

By Edward Keller

In a paper, " A Study of the Elimination of Impurities from Copper-Mattes, etc.," presented to the Institute at the Atlantic City meeting, February, 1898, I gave certain figures which I called the relative slaggability in refining copper. In that paper* will be found the following pertaining to this subject: Relative Slaggability in Refining Converter-Copper. Cu. Pb. Bi. Sb. As. Se, Te. 1 129.5 1.13 7.30 5.22 0.81 and Relative Slaggability in Refining Electrolytic Copper. Cu. Pb. Sb. As. 1 41 9.97 7.13 Since there is a, possibility of misinterpretation of the above values, the following supplementary information may seem justified in explanation. As the contents of impurities in the unrefined or crude copper were unknown, the contents of the refined copper were substituted therefor, merely in order to obtain the two series of figures for comparison. These figures are higher than they would be had I been able to take the correct ones for the unrefined copper. The high figure, 129.5, for lead, in the case of converter-copper, means simply that more lead was slagged from the crude copper than remained in the refined copper; or, in definite values, that to 1 per cent. of copper slagged, the ratio of the lead gone into the slag and the lead remaining in the refined copper is 129.5 : 100. It is possible to approximate the true slaggability much more closely by adding the quantities of impurities in the refined copper to those in the slag, thus obtaining values for the crude copper in which the amounts volatilized are ignored (the latter

Jan 1, 1901

I find that during the short time I have been in this district, the majority of boilers are, and have been, receiving very bad usage owing to the difficulties which they have to contend against, viz., oil and bad water. Oil on the heating surface of a boiler is of a highly dangerous nature inasmuch as it allows the surface to become overheated, owing to the water not coming into direct contact with the plates, and it naturally follows that when the crown sheets of a flue or firebox become overheated, you lose a considerable amount of the strength of the plate, and the flue or crown comes down. Referring to the oil question, I find that too much care cannot or exercised on the part of engine drivers in order to minimise as much as possible the internal lubrication of the various engines under their control. For I consider that it is here that the most of the trouble is caused. My reasons for stating such to be the case, are:-That the majority of enginedrivers before coming to this field have been used to driving engines that have been exhausting into the atmosphere, and probably they have been taught that it is far better to use a little extra lubrication than to have a hot bearing. So far so good. But one thing that must not be overlooked is that on these fields the conditions are altered in this respect, as the majority of engines in this district are not exhausting into the atmosphere, but are condensing their exhaust steam and using the water so condensed for feed purposes.

Jan 1, 1901

When the first rush of miners took place on the Molyneux River, in the Dunstan Gorge, the gold was won by means of cradling the gravel, which was shovelled from the various beaches and crevices in the rock-bound sides of the river.The above method of winning the gold was only practicable when the beaches were not covered with water, hence the work was usually carried on during the winter months, the ordinary level of the river during spring and summer months being some ten or twelve feet above winter level. The melting of the spow in the Lakes water-shed being responsible for the high summer level of the river.As the available beaches were worked out, other methods of winning the gold were proposed and worked with more or less successful results the first advance being to work the bed of the river by means of a spoon dredge. The spoon was made with a round lip or ring of iron, having a steel cutting edge on one half of the circumference, at the opposite side a socket being forged to take a long spar or boom, which was securely fitted thereto. At intervals round the hoop, half-inch holes were bored to enable. a bullock-hide bag to be laced on to same. The spoon was worked from a pontoon which carried a crab winch, tackles and the necessary washing appliances to treat the washdirt lifted. In starting to dredge, a tackle was attached to near the upper end of the boom, and a line or chain was carried over a cat head from the crab winch...

Jan 1, 1901