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By L. H. de Wald, J. Walter Scott

The removal of lead by fire refining methods from copper of electrolytic quality is growing in importance. Particularly is this true of the refining of secondary copper and copper cathodes obtained from electrolytic cells where lead is used as the anode material, as in the electrolysis of ore-leaching solutions and foul electrolyte. When investigating the removal of small amounts of lead from molten copper in a reverberatory furnace during the refining of secondary copper of otherwise electrolytic copper quality,' it was found necessary first to know something about the distribution of the lead throughout the bath. The authors believe that it is not generally known how small amounts of lead as an impurity are distributed in a molten copper bath; that is, whether the lead is concentrated at the bottom or at the top, or whether it occurs more or less uniformly throughout the bath. The data contained in this report may help, therefore, in the development of a satisfactory fire refining method for the removal of this obstinate element from a molten copper bath. The first step was the development of a method for taking samples from various locations in the bath, at the surface and at various depths. The sampling device used, shown in Fig. 1, consisted of a 10-gram fireclay assay crucible fitted into a ring on the end of a steel rod handle of suitable length. A fireclay scorifier, 2 in. dia., with a ½-in. hole bored in the

Jan 1, 1930

The United States Bureau of Mines frequently receives requests for information regarding the details of its organization and the nature of its activities. In response to such an inquiry a series of articles outlining the work of the bureau as a whole and of its different divisions was prepared and published in the United States Daily, Washington, D. C., during November, 1929. These articles are reprinted here in the hone that they may assist in giving the public a more complete understanding of the aims and purposes of the bureau and the methods by which it is laboring for the attainment of safer conditions and more efficient methods in American mineral industries. An index of these articles, with the dates of 'their publication in the United States Daily, is given below.

Jan 1, 1930

By C. R. Whittemore

Introduction The technical library in the service of industry is gradually becoming a well recognized and important part of all progressive industrial organizations. The larger mining, metallurgical, and chemical firms of Canada are establishing extensive reference libraries in connection with their research and operating departments in order that the members of the organization may keep abreast of the rapidly developing fields of engineering in which they are interested. It is the purpose of this paper to point out the usefulness of such a department in any industrial organization, to give a general outline of a system for filing and dispensing information, and to outline briefly the literature to be consulted and the procedure to be adopted in instigating a literature search. The technical library falls under the classification known as 'Special Libraries', and is quite different from the general library in that it is a storehouse of facts and owes its value to the ready presentation of information required for each specific case, and in a form most ready for use. The library brings all the available information relative to the interests of the corporation from without the plant to the organization within, and also keep in touch with each department of the organization.

Jan 1, 1930

By James W. Wade

This paper describing the mining practices at the Tintic Standard mine is one of a series being prepared by the United States Bureau of Mines. In the preparation of this paper each subject has been presented by the engineer in charge. L. R. Dobbs wrote the part pertaining to tae technique of square-set mining, J. M. Snow the part on geology, and M. D. Paine, the part on ventilation. All of the drawings are the work of H. W. Waterfield of the engineering department. The statistics of the Tintic district ware prepared by A. G. MacKenzie. Each writer has attempted to show the difficulties that arise in operating and the practices used to overcome them.

Jan 1, 1930

By E. Stansfield, J. W. Sutherland

It is well known that the ash left when coal is burned is not the same either in chemical composition or in weight as the mineral matter originally present in the coal. This mineral matter has been referred to as "mineral impurity," "ash-forming constituents" and "corrected ash." The authors prefer the simple name used in the title and throughout this paper. The mineral matter in a sample of coal cannot be isolated unchanged and then weighed; but if the relation between the weight of mineral matter in the coal and the weight of ash remaining when the coal is burned can be ascertained, the weight of mineral matter in the sample can be calculated from the determined weight of ash. When the weight of mineral matter in the sample is known, the weight of pure coal can be found by subtraction. This pure coal must be the basis of accurate coal classification. W. F. Wheeler,l,3 W. Brinsmaid,2 S. W. Parr, and many subsequent workers have studied the relation between mineral matter and ash. Wheeler and Parr and others have deduced formulas for calculating this ratio, and used heavy-solution separations for checking the accuracy of their formulas. Brinsmaid hand-picked and analyzed two separate samples (and mixtures of these) and based thereon a graphical method of deducing the ratio. In the Fuel Testing Laboratories of the Scientific and Industrial Research Council of Alberta, a graphical method, based on heavy-solution fractionation of coal samples, has been used with marked success for the past 7¼ years for determining the mineral matter-ash ratio. This method resembles that employed by Brinsmaid in 1907.

Jan 1, 1930

By Elford H. S

Mr. H. W. GEPP said he desired to bring particular attention to this paper. The underlying intention of the Development and Migration Commission when the paper was prepared was to place at the disposal of Australian miners and metallurgists the story of the development of tin metallurgy as it had been advanced in other countries, particularly Great Britain. They had very considerable resources of low-grade tin-bearing metals in the eastern coast of Australia particularly, and they need not anticipate that tin was going to remain at the extremely low price at which they saw it to-day. The Commission felt that it was most desirable to place 'on record, and make easily available, the story of the treatment of comparatively low-grade tin ores in other parts of the world.Arrangements were made that the technical staff at Australia House, in conjunction with Mr. H. S. Elford; should collect this information so that in due course, when Australia awoke to an interest in low-grade deposits, of which there were many throughout Australia, this story would then not,have to be gathered from other areas and other places of the world. The -paper was a contribution which would turn out to be of very great value. He suggested to the younger members that this thorough contribution could be made the subject of study so that they would be ready to assist in the developments which must come. Mr. WM. APLIN said there was one point in connection with the paper upon which he would like to speak. While at Mount Morgan he had occasion to test some highly pyritic tin ore by flotation, with a view to separating the cassiterite from the pyritic mineral.Instead of accomplishing that, it was discovered that it would be possible to eliminate as much as 50% of the total weight of ore in the form of a pyritic flotation concentrate, which would contain...

Jan 1, 1930

By Harley A. Coy

This paper, describing the mining methods and practice at No. 2 mine of the American Zino Co. of Tennessee at Mascot, Tenn., is one of a series of papers issued by the Bureau of Mines presenting the mining methods and costs in various districts throughout the United States. Its purpose is to summarize methods recently put into practice whereby increased efficiency has been effected. These improvements have to do principally with mill-hole mining, slushing, contract labor, and bonuses. In general, this paper supplements earlier articles and brings them up to date. ACKNOWLEDGMENTS The author acknowledges the assistance of M. H. Newman, geologist of the American Zinc, Lead & Smelting Co.; of William Black, assistant superintendent of mines; of P. M. Arthur, director of personnel; and of the engineering staff. The paper has been approved by H. I. Young, vice president and manager of operations.

Jan 1, 1930

By Oscar Glaeser

THE United Verde Copper Company's mine is at Jerome, Ariz. The orebodies are of the schist replacement type, the main sulfide mass being a large lens-shaped body approximately 7 acres in cross-sectional area. In general, the mineralization is found along the iron schist contact, with the orebodies extending about 1000 ft. along this contact and varying from a few feet to 250 ft. in width. Three types of ore are mined; schist porphyry and the so-called "heavy" or "massive sulfide" ore. Approximately 50 per cent. of the total tonnage mined at present is of the latter class. A representative analysis of this ore indicates 42 to 46 per cent. sulfur. Because of the high sulfur content, blasting in this ore is an extremely hazardous operation. Not only does it endanger the lives of men who may be in the mine at blasting time but it also becomes a potential fire menace when timber is in close proximity to shots being fired in these massive sulfides. The origin of the fires of 38 years ago, embers of which are glowing to this day, may perhaps be attributed to dust explosions due to blasting in the massive sulfides of those, early square-set stopes.

Jan 1, 1930

By W. Francis

Before attempting to describe the application of recently acquired knowledge to the classification of coal it will be as well to consider the objects at which a scientific classification should aim. Here one can not do better than to follow the example of Clarence Seyler,l by quoting from Huxley's "Classification of Animals:" "By the classification of any series of objects is meant the actual or ideal arrangement together of those which are like and the separation of those which are unlike, the purpose of the arrangement being to facilitate the operation of the mind in clearly conceiving and retaining in the memory the characters of the object in question. Thus there are as many classifications of any series of natural or other bodies as they have properties or relations to one another or to other things. But the statement of the characters of the class ... is something more than an arbitrary definition ... it expresses firstly, a generalization based on and constantly verified by very with experience; and, secondly, a belief arising out of that generalization—in other worda. the definition of the class is a statement of a law of correlation or coexistence . . . from which the most important conclusions are deducible." In that same sense writes John Stuart Mill, in the chapter on classification in his "Logic:" "The ends of scientific classification are best answered when the objects are formed into groups concerning which a greater number of general propositions can be made, and these properties more important, than could be made respectiug any other groups into which the same things could be distributed. The properties, therefore, according to which objects arc classified should, if possible, be those which are causes of many other properties, or, at any rate, which are sure marks of them." Now in the case of coal, the properties which have been used from time to time for classification purposes are the ultimate analysis, volatile matter, caking power, calorific power, burning properties, etc. Seyler has shown that there is a general law of correlation or coexistence between the ultimate composition and the other properties. The ultimate composition, therefore, of the natural series of bodies known as coal is the

Jan 1, 1930

By John M. Rayburn

When plans were made for the new mine of the Allegheny-Pittsburgh Coal Co., Springdale, Pa., it was decided to operate on the room and pillar system, but not to have any extensive room development, the pillar work being done altogether on the retreat. On each room heading five rooms were to he driven advancing, while five pillars were being removed, so timed as to form a continuous pillar line, with all approaching

Jan 1, 1930

By K. H. March

In the present very highly competitive condition of the bituminous coal business, it is becoming increasingly apparent that coal mines which do not lend themselves to efficient mechanization cannot long survive. It would seem that those mining operations best fitted to survive the struggle for existence are burdened with the considerable capital and maintenance cast of carefully selected mechanical and electrical mining equipment. The ever changing conditions of coal mine operations require equipment which is adaptable to a variety of uses; and investigation of the mechanical and electrical equipment in most mines will show that the operating duty of much of this equipment is considerably different from that duty for which it was originally selected. And it would appear that one of the essential qualifications for a successful mine management is a marked ability to get satisfactory operating results from equipment which has been transferred from some other operation, rebuilt, rearranged, or in some way adapted to the job at hand. As a striking example of such mechanical ingenuity, many of us recall that the first longwall jigging conveyor used in Nova Scotia was built in Sydney Mines from odds and ends in the scrap pile at a total cost of less than $50.

Jan 1, 1930

By H. Tomlinson

The development of the Sevier Valley Coal Co.'s mine marks the opening of the Salina Canon coal district in Utah. The mine is favorably located with respect, to the existing markets of the West, and if the present estimates of the amount of workable coal in it are accurate it has many Important advantages in favor of its development. This mine is situated 18 miles east of the town of Salina, Sevier County, Utah, which at present is the nearest shipping point oh the Marysvale branch of the Denver & Rio Grande Western Railroad, and is about 152 miles south of Salt Lake City, which is the distributing center for much of the coal from the Carbon - Emery coal field and is the place from which nearly all Utah coal shipped to San Francisco and points on the northern Pacific coast has a common haul.

Jan 1, 1930

By D. J. Jr. McAdam

RESULTS of a general survey of corrosion-fatigue phenomena at the Naval Engineering Experiment Station were presented in five previous papers.1-5 In these papers references were given to the work of Haigh in 1917.6 The five papers mentioned gave a general survey of the behavior of metals when tested to failure under simultaneous corrosion and cyclic stress. As a result of this survey the fourth paper gave a tentative analysis of the corrosion-fatigue process. According to this analysis, if the initial stress is below the endurance limit but above the corrosion-fatigue limit, the corrosion-fatigue process is divided into two periods. The first period is the formation of pits. As the initial stress is below the endurance limit, the pitting is assumed to be due to corrosion, not to fatigue. The corrosion pitting, however, is not the ordinary pitting of stressless corrosion, but is an accelerated pitting due to the effect of the cyclic stress on the corrosion. As the pit progresses, both the actual stress and the effective solution pressure increase. The increase of actual stress is due to increasing stress concentration at the bottoms of the pits. The increase of effective solution pressure is due to the increase of actual stress. The mutual intensification of stress and solution pressure continues until the actual stress at the bottoms of the pits surpasses the endurance limit. The second period of corrosion-fatigue then begins. In this period the process is merely fatigue accelerated by the corrosion. The cracks advance at a continually accelerated rate until the specimen breaks.

Jan 1, 1930

By C. H. Attwood

Introduction In presenting this paper on the water-power resources of the Province of Manitoba, it was considered that a brief resume of the power resources of Canada, of the power already developed, and its utilization in the industries 9f the country, would be of particular interest in showing the rapid progress that has already been made. Amongst Canada's national assets, water power occupies a foremost place because of the facilities it provides for the development of her other great natural resources. The rapid development of the mining, pulp and paper, and general manufacturing industries, and the concomitant growth in urbanization, with its numerous demands for domestic, commercial, and municipal service power, have combined to stimulate hydraulic development to a point surpassing even the most sanguine predictions of a few years ago. With the bringing into operation during 1928 of hydraulic turbines aggregating over 550,300 h.p., and of a further 378,400 h.p. in 1929, Canada's total hydraulic development at the end of 1929 amounted to over 5,700,000 h.p., and in this year, 1930, the active construction in hydro-electric plants throughout the country totals in excess of 1,600,000 h .p.

Jan 1, 1930

By F. S. Wartman

Recent changes in metallurgical practice, particularly those in flotation, have altered greatly the functions of the different units of a copper smelter. Gangue minerals are removed from the feed so much more thoroughly that the reverberatory furnace, once virtually a concentrator in which a low-grade ore was concentrated into a rich matte by virtue of the removal of gangue elements as slag, has become very largely a melting furnace in which the rich flotation concentrates are rendered molten so that they may be converted. Moreover, since the proportion of matte to slag in the reverberatory furnace output is greater than it was formerly, the amount of converter slag returned to the reverberatory for cleaning is, in comparison to the amount of slag actually formed in that furnace, also much larger. In some cases, approximately half of the reverberatory dump slag may have originated in the converter. The increase in the proportion of convertor slag to total slag produced has brought about certain consequences not entirely desirable. Converter slags contain a high percentage of iron and therefore are high in specific gravity and are very basic. A considerable guantity of magnetite, both dissolved and suspended as solid crystals, is always a component, The basic nature of the ordinary converter slag and the presence of the suspended magnetite crystals make impossible the reduction of the copper content of the slag below approximately 1 per cent by even the most prelonged settling, and a re-treating process is necessary. At present, general practice in western copper smelters is to return the converter slag molten to the reverberatory furnace. Here dilution by mixing, with slag formed in the reverberatory furnace and reaction with raw sulphides and siliceous materials in the reverberatory feed reduce the magnetite and increase the silicates to the point necessary for a satisfactory dump slag.

Jan 1, 1930

By George W. Sears

In preparing this symposium, our ambition was to elicit authoritative expression of opinion concerning important selected phases of the industry from men active in it. Responses to requests for contributions were gratifying, especially so in view of the short time available. The generous and cooperative spirit of the industry as a whole is amply evident. Responses were received from the following, who are therefore the true authors of the paper: W. G. Adamson, General Manager of the pershin; Quicksilver Co., Lovelock, Nev.; Dudley Baird, Vice President, Pacific Foundry Co., San Francisco; Walter W. Bradley, State Mineralogist of California; W. D. Burcham, General Manager of the Brewster Quicksilver Consolidated, Terlingua, Tex.; William Forstner, San Francisco; H. W. Gould, of H. W. Gould & Co., San Francisco; Marcus Hulings, General Manager of the Chisos Mining Co., Terlingua, Tex.; Frank J. Katz, Chief Engineer, Division Mineral Statistics, United States Bureau of Mines, Washington, D. C.; Lloyd J. Lathrap, Superintendent, Nevada Quicksilver Mines, Inc., Lovelock, Nev.; W. R. Moorehead, General Manager, New Idria Quicksilver Mings, Inc., Idria, Calif.; F. W. Oakes, Jr., Terlingua, Tex.; C. N. Schuette, San Francisco. Brief Economic History of Quicksilver in the United States Quicksilver ore was first discovered in the United States at what was later the New Almaden mine in California, in the year 1824. Production also began here, but not until 1850, when it was stimulated by the active demand caused by gold-mining operations. Prospecting for quicksilver was active, high-grade ores were found and ample production lowered the price from $100 per flask in 1850 to about half that figure for the greater part of the next 10 years. During the succeeding decade, many new quicksilver mines were found; production increased at a time when the local demand diminished, so that most of the product was exported. The third decade of quicksilver mining in the United States witnessed the development of the pan amalgamation process, particularly in Com-stock silver-mining operations. A suddenly increased demand sent prices soaring, the all-time peak of quicksilver production followed, and the highest price was soon replaced by the lowest one on record. Huge quantities of quicksilver were exported between 1870 and 1880 and exports continued in decreasing measure for three decades to 1910. In

Jan 1, 1930

By A. W. Fahrenwald

[In studying coarse sand flotation3/ the question of the relation between fineness of grinding and mill capacity logically arose. Everyone familiar with present fine-grinding practice knows that the capacity of a ball mill or similar mill is determined, among other things, by the fineness of the finished product. Undoubtedly a great many mining companies must have a good deal of data directly bearing on this point, yet no quantitative relationship between ball-will capacity and fineness of finished product has been established. The experimental study presented here is an effort to establish this relationship in a semiquantitative way. The subject is a tremendously large one and grows in complexity as the study becomes more searching. In this work the power consumed by the mill in the various experiments was not determined end neither vas the steel consumption measured; mill capacity only was considered.]

Jan 1, 1930

By J. Ander

About fifteen years age some mines in western Canada commenced using Diesel engines, partly for development work but also for operations on quite a large scale. In the Eastern mining field, the Diesel engine made its appearance some eight years ago and has since, at quite a number of mining plants, proved to be a reliable and economical prime mover. As a result, it is today used more extensively than could have been foreseen only a few years ago, and it is reasonably safe to predict that the next few years will see the Diesel engine utilized to a still greater extent in the Canadian mining industry. It is not much more than thirty years since the first Diesel engine was put in operation. During the early years of this century, the Diesel engine took, so to say, its first faltering steps in public service. Since then it has reached a high state of perfection, and its importance has grown in a most remarkable way, until today it is used in practically every field where power is required. It is slowly but surely superceding steam for a great many purposes, as, for instance, for ship propulsion. While in 1921 only about 8 per cent of all tonnage launched was motor-driven, the proportion had grown to 38 per cent in 1927, and for 1929 it was slightly over 45 per cent. Some of the finest passenger liners afloat are Diesel-driven. In the early days, Diesel engines were built only in comparatively small units. Today engines with a capacity per unit of up to 10,000 horsepower, or even more, are being built for marine and stationary purposes.

Jan 1, 1930

By Arthur F. Taggart

The following notes represent significant excerpts from a mass of records of experimental work done in the ore-dressing laborattory at the Columbia School of Mines during the years 1926 to 1928 inclusive. Classification of Experimental Work The experiments performed may be grouped for purposes of description under the following general headings: I. Collecting agents. a. A method for quantifying collecting effect. b. Coating with undissolved collecting agents (oils). c. Action of dissolved collecting agents. II. Frothing agent's. a. A method for quantifying frothing effect. b. Relation between frothing effect and chemical composition. III. Inorganic reagents. a. Methods of studying the effects of these reagents. b. Effect on slime dispersion. c. Effect on sulfides. Summary of the Origins of Present-day Flotation Practice The first practicable, foolproof method of froth flotation was described in U. S. Patent 835120, issued in 1906 to Sulman, Picard and Ballot, and in the equivalent patents in other countries. A number of less simple methods of producing the same result had been described previously in patent publications and otherwise.' The reagents specified in all of these early patents were "oils" and, in addition, some inorganic substance, usually an acid. The quantities of reagents recommended and added were enormous when compared with those used today.

Jan 1, 1930

By O. M. Schaus

The following is a description of the methods employed at the Eureka-Asteroid mine, which is situated on the Gogebic range, at Ramsey, Mich. The mime is operated by the Castile Mining Co. under the direction of Oglebay Norton & Co. This paper has been prepared in accordance with an outline furbished by the United States Bureau of Mines, and in one of a series, on mining methods and costs covering the principal minim operations throughout the United States. ACKNOWLEDGMENTS The author acknowledges the assistance of the mining organization of the Castile Mining Co. in the preparation of this paper.

Jan 1, 1930