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The Library of the above-named Societies is open from 9 A.M. to 9 P.M. on all week-clays, except holidays, from September 1 to June 30, and from 9 A.M. to 6 P.M. during July and August. The Library contains about 55,000 volumes, including sets of technical periodicals and the publications of scientific and technical societies. Members of the Institute, with few exceptions, are forced to spend a portion of their time in localities isolated from sources of information. To these the Library can render valuable service through correspondence; letters requesting information will receive special attention. The Library is prepared to furnish references and copies of articles on mining and metallurgical subjects; to determine the existence of mining-maps, and to furnish general information as to the geology and mineral resources of all countries. All communications should be made as definite as possible so that the information received may be what is desired and not include collateral matter which may not be of interest. The time spent in searching for such collateral matter will be saved, and the information will be sent more promptly and in more usable shape. The members of the Institute can be of service to the Library by forwarding copies of mining-reports, maps privately issued, and similar material, which will be classified, indexed, and made available to other members. Suggestions for additions to the Library, either by purchase or personal solicitation as gifts, will be welcomed. It is hoped that members while in the city will use the Library freely, and assurance is, given that most careful service will be rendered to them.

Jan 9, 1913

By Bruno Nordberg

THE high cost of coal in Butte and the development of large amounts of cheap electric power from the Missouri river caused the Anaconda Copper Mining Co. in 1908 to make an investigation as to the possibility of adapting this cheap electric power for the operation of their many large hoisting plants. At this time electric power had already been adopted for practically all other power purposes around the mines, such as pumping, compressing air, etc. The map (Fig. 1) shows the location of the mines of the Butte mining district. These mines are located within a circle of approximately a 1-mile

Jan 9, 1913

By W. L. Saunders

IMPORTANCE OF ROCK DRILLING. IT has been estimated that the value of the mineral products of the United States is about $2,000,000,000 a year; that about $25,000,000 is expended. annually for explosives and that about double this sum is paid in wages where blasting is done. The value of the mineral products does not adequately express the importance of the industry involved in the excavation of rock and ore because of the enormous sums of money expended in tunnel driving, in quarries, and in open-cut excavation generally. We know that the Catskill Aqueduct in the neighborhood of New York, which is now nearing completion, has cost some $165,000,000 and that about one-third of this may be rated as rock excavation. These illustrations are given in order to call attention to the great importance of an industry the extension and development of which in our industrial life depend so much upon the economics of rock drilling. Reference has been made to the new Catskill Aqueduct. There are three aqueducts leading into New York, each built at periods separated by some 20 years of time. 'The first one, known as the Old Aqueduct, conveys the waters of the Croton river to New York City in a manner which reminds one of the old Roman aqueducts, the ruins of which are still in evidence. The engineers who laid out these old conduits sought to direct their lines around the hills and into the valleys, at all times avoiding the rock. When it was necessary to cross a river or a deep ravine, a bridge or causeway was constructed. High Bridge, over the Harlem river, is an arched masonry viaduct differing in no essential features from the aqueducts of the Romans. When the second Croton Aqueduct was built, about the year 1890, the art of drilling rock had been so far perfected, and the use of explosives, through the invention of dynamite, had become ,so general, that this waterway was planned and executed on straight lines, following rather than avoiding the rock. The second Croton Aqueduct is a tunnel through rock, about 32 miles in length; material gneiss, almost as hard as granite. Its construction was made practicable by sinking

Jan 9, 1913

By Albert Wiggin

THE copper-bearing sulphide ores from the mines in Butte, Mont., which are for the most part concentrated at the Boston & Montana duction Works in Great Falls and at the Washoe Reduction Works in Anaconda, contain the following minerals of economic value: Chalcocite, Cu2S; enargite, Cu3AsS4; cupriferous pyrite; bornite, Cu3FeS3; covellite, CUS; tetrahedrite, 4 CuS2Sb2S3; and tennantite, Cu8AsS7;. All of the ores carry a high percentage of pyrite. Many of the above sulphides are argentiferous and also carry from 10 to 20 cts. per ton in gold. The gangue is quartz and highly altered granite, with sphalerite and galena and more rarely barite and hubnerite as accessory minerals. An average chemical analysis of the second-class ore concentrated at Great Falls and Anaconda would be as follows: Copper 3.2 to 3.4 per cent. Silver 2. 3 to 3.0 oz. per ton. Gold 0.0-1 to 0.15 oz. per ton. Si02.. 55 to 60 per cent. FeO 12 to 15 per cent.. Sulphur 12 to 1.5 per cent. Al2O3, S to 10 per cent. CaO 0.5 to 0.8 percent. As203, 0.5 to 0.6 percent. Lead 0.2 to 0.3 percent. Before describing the Great Falls flow sleet as installed, at Anaconda, a brief history of the Great Falls concentrator will be given, including a description of the various concentrating machines and systems which have been tested in the search for a flow sheet which would give a higher recovery of copper.

Jan 8, 1913

By D. C. Bard

THESE notes are based on the megascopic study of a suite of 2,400 specimens of minerals and ores from the Butte mines, combined with field observations at intervals over a period of several years. The estimate of average vein composition is based on field acquaintance with the veins. It is probably correct in its broader proportions, and should be of use for comparison. Chemical and Mineral Composition of Butte Sulphide Vein. Matter. Per Cent. Oxygen 43.00-Quartz, rhodonite, rhodochrosite, barite, calcite, and hübnerite. Silicon 36.00-Quartz, rhodonite, and willemite (very rare). Sulphur 5.00-Sulphides of. iron, zinc, copper, lead,. and sulphates of barium and rarely calcium. Iron 5.00-Ferric sulphides (pyrite, bornite, chalcopyrite), also in sphalerite, tetrahedrite, and rarely hematite and siderite. Manganese, . . . . 2.00-Rhodonite, rhodochrosite, and hübnerite. Zinc, . . . . 1.00-Spha erite, very rare wurtzite and willemite, and tetrahedrite and tennantite.

Jan 8, 1913

One of the results of the work of the Committee on Precious and Base Metals is that the present Bulletin is as large as some of. the annual volumes of Transactions of the Institute, and we extend our. compliments and thanks to the Committee and express to the members thereof and to. the authors, who have so bounteously given of their time and information, the. sincere gratitude of the Institute. In order to get all these papers printed and distributed to the membership in advance of the meeting, it was necessary to divide the work between two printers. This accounts for the discrepancy in the pagination of the Bulletin; and we also ask the indulgence of our readers in case errors have crept into this preliminary edition during the period of unusual pressure. Program of the Butte Meeting.-The program of the Butte meeting will include six technical sessions for the presentation and discussion of papers and five half-clay visits to mines and metallurgical works. The following program is practically in final form, with slight additions which may be necessary later. Every effort will be made to have papers presented and discussed on scheduled time, so that members who are unable to attend the entire meeting may so plan their trip as to hear and discuss papers in which they are especially interested.

Jan 8, 1913

By Ralph Hayden

I. INTRODUCTION. IN the wet concentration of ores there is always a certain amount of very fine material with which to contend, and which invariably carries such quantities of value that the treatment of it is worth while; commercially. This fine material usually contains that portion of the ore which hinders the separation of the mineral values: namely, the colloidal material resulting from the decomposition of certain constituents of the ore. The object of this paper is to show what efforts have been made to solve the slime problem as it occurs in the concentrator of the Washoe

Jan 8, 1913

STANDING COMMITTEES. Executive. CHARLES F. BAND, Chairman. JAMES F. KEMP, JOSEPH W. RICHARDS, ALBERT R. LEDOUX, BENJAMIN B. THAYER. Membership. BENJAMIN B. THAYER, Chairman. WALTER R. INGALLS, JOHN H. JANEWAY, JR., JOHN D. IRVING, HERMAN A. PROSSER. Finance. EDWARD L. YOUNG, Chairman. KARL FILERS, JAMES GAYLEY. Library. JAM ES, F. KEMP, Chairman. JOHN HAYS HAMMOND,3 E. GYBBON SPILSBURY,2 ALEX. C. HUMPHREYS,4 BRADLEY STOUGHTON.

Jan 8, 1913

By Edward Keller

THE ASSAY FOR COPPER. SOMEONE some time ago remarked that some chemists still insist on telling us how to determine copper by the electrolytic method. The. writer must confess that he believes that everything is not known definitely as yet as to how the exact amount of copper is determined in such material as purest commercial electrolytic copper. Some of us are not yet convinced that the pure copper atom is at all times deposited from an acid solution and that no oxygen or hydrogen will, under certain conditions, accompany it. Difficulties with impurer material are frequent, but erroneous results are not always apparent, since these do not speak so readily for themselves as those in the first case. By this is meant that if a chemist finds 100 per cent. of copper in electrolytic copper it is pretty certain that he perceives the result to be wrong, while if he finds 0.1 per cent. of copper too much in a very impure material he is far more likely to be unconscious of his error. These, in a wide experience, are frequent happenings and the writer has always looked with interest to publications on this subject. In turn, he :feels justified in giving to others a few of his own observations. Up to a few years ago there were two methods of electrolytic copper assay in technical use, which had in common, that the amount of copper deposited on the cathode did not exceed 2 g., and they differed in that, for the one a large sample 1 (20 to 80 g.) was taken from the general sample by a splitting device, dissolved, and from the solution a small portion (to contain 1 or 2, g. of copper) measured out for the electrolytic deposition; in the other Method the copper was determined, generally in 1-g. portions of the separated coarse and fine portions of the sample, all of which passed -a 16 or 20-mesh screen, being accomplished by a 40-mesh screen,

Jan 8, 1913

By Robert Ammon

THE purpose of this paper is to present a brief sketch of the development of this hindered-settling classifier, but primarily to show the actual results obtained in practice with the classifier working on the Butte copper ores at the Boston & Montana Concentrator, at Great Falls and the Washoe Concentrator at Anaconda. The writer has endeavored to be as brief as possible, giving only the essential figures showing the efficiency of the classifier and leaving considerable interesting information to be derived by the reader from the statistics given. The paper deals with the practical work of the classifier under the following heads: 1. Desliming 4.0-mm. primary feed, overflow from 0.07 to 0.0 mm. 2. Desliming 1.25-mm. secondary feed, overflow from 0.07 to 0.0 nun. 3. Desliming Huntington Mill discharge, overflow from 0.07 to 0.0 mm. 4. Classifying 2.5-mm. deslimed secondary feed, overflow from 1.00 to 0.07 mm. 5. Classifying 2.5-mm. deslimed primary feed, overflow from 0.75 to 0.07 mm. 6. Classifying 4.0-mm. deslimed primary feed, overflow from 0.75 to 0.07 mm. 7. Classifying middling-tailing product from roughing tables, overflow coarse tailing. 8. Classifying 2.5-mm. trommel undersize, not deslimed, overflow from 0.75 to 0.0mm. 9. Remarks on the inner feel cone. In the following pages all overflows, are given in quartz dimensions; i.e., by a 0.75-mm. overflow 'is meant an overflow whose maximum particle is a 0.75-mm. quartz grain. By the term "slime" is meant all material which will pass through a 200-mesh screen whose average opening is 0.07 mm.

Jan 8, 1913

By Norman Braly

THE following is not offered as an extended paper on the subject of shaft sinking, but more as a description of the present practice of shaft sinking in the Butte district. The Anaconda company is sinking at present the following shafts: Badger State, Moose, Mountain Consolidated, Mountain View, Pennsyl-ania and Tropic. At the High Ore and Leonard mines the shafts are being deepened by sinking two compartments and will subsequently be enlarged to the full working size by raising alongside the compartments which are now being sunk. The following other companies are also sinking shafts: Butte-Alex Scott, Butte and Zenith City, Boston and Corbin, North Butte Mining Co. (at the Granite Mountain shaft), East Butte Co. (at the Pittsmont shaft), and the Rainbow Lode Development Co. Shaft Timbering. The shafts of the Butte district, generally speaking, are of three compartments arranged in a straight line, and the pump compartment is usually arranged for the use of an auxiliary hoisting cage, as well as for carrying pipe lines and electric wires. The Rainbow shaft is practically square, and of three compartments. The length of the shafts outside of timber will vary from 17 to 22 ft., and the width from 6 ft. 6 in. to 7 ft. Fir timber is used in all shaft work. This may be obtained from the Coast, when it is known as Coast fir, or from Idaho or Montana, when it is known as native fir. The native fir seems to be the tougher wood, but it is hard to obtain clear lumber in the lengths and sizes necessary for shaft work. Some of the shaft timber of the Anaconda company has been treated with creosote as a preservative, but this practice has not come into general use, as the ground of the camp is so heavy that the timbers usually crush before they rot. The size of timber most .used for shaft work is 12 by 12 in., while 10 by 12 in., 10 by 14 in. and 12 by 14 in. are used for some of the special pieces around the shaft. The new Leonard shaft is timbered with 14 by 14 in. wall plates throughout.

Jan 8, 1913

By Willis Burns

I. INTRODUCTION. These notes are submitted, not as a discussion of the modern practice of electrolytic-copper refining, but as the record of a refinery that was among the pioneers in the field and that is to-day, and has been for 17 years, operating under conditions not to be found in any similar plant in the country. I refer to the current density, which is at least 60 per cent. higher than that regularly employed elsewhere, and to the fact that the anodes treated are the direct product of the converter rather than of the reverberatory furnace. The writer has no knowledge of any other refinery treating anodes of this character.

Jan 8, 1913

By E. E. Brownson

THIS paper will be confined to the treatment of methods as applied in the laboratory of the Boston and Montana Reduction Department of the Anaconda Copper Mining Co. at Great Falls, Mont. As the electrolytic plant of this company operates at a current density of approximately 35 to 40 amperes per square foot when running up to capacity, the arsenic and antimony content of the anodes delivered to the, plant is of considerable importance as bearing on the purity of the refined cathodes turned out. Owing to the rather high relative percentage of antimony, it has always been the custom to determine antimony as well as arsenic in all forms of copper. Thus, anodes have been analyzed in which the antimony was about equal to the arsenic although the average shows about 2 parts of arsenic to 1 of antimony. In the refined copper the relative proportions of the two impurities vary considerably, but probably in the average are about equal. In this latter case, the percentage of the two is so small that ordinarily no attempt is made to separate them, the report of analysis showing percentage of As and Sb combined. Although rapid and exceedingly accurate determinations of arsenic may be made by means of various distillation schemes, the determination of antimony, either by itself or together with arsenic, has always been more or less cumbersome and has required a considerable amount of time. By the methods, details of which follow, the determination of arsenic and antimony, either separated as in the case of anodes or together in case of refined copper, is accomplished in 24 hr. from the time the sample is received by the chemist.

Jan 8, 1913

PRESIDENT. CHARLES F. RAND,1 NEW YORK, N. Y. PAST PRESIDENTS. CHARLES KIRCHHOFF,1 NEW YORK, N. Y. JAMES F. KEMP,2 NEW YORK, N. Y. FIRST VICE-PRESIDENT. BENJAMIN B. THAYER,1 NEW YORK, N. Y. TREASURER. GEORGE C. STONE,1 NEW YORK, N. Y. SECRETARY EMERITUS. ROSSITER W. RAYMOND NEW YORK, N. Y. SECRETARY. BRADLEY STOUGHTON, NEW YORK, N. Y.

Jan 8, 1913

INTERNATIONAL GEOLOGICAL CONGRESS. (For further particulars apply to the Secretary, 12th International Geological Congress, Victoria Memorial Museum, Ottawa, Canada ; cable address, Geocong, Ottawa.) The Coal Resources of the World.-Three quarto volumes of about 400 pages each, 8 1/4 by 10 3/4 in., and an atlas of about 70 maps in colors, 13 1/3 by 19 1/2 in., bound in heavy paper cover. Edition limited to 3,000 copies, One thousand copies will be reserved for members of the International Geological Congress, and the remainder of the edition will be distributed in the order in which applications are received. Price, $35 per set. Ready in July, 1913. This book is an inquiry made upon the initiative of the Executive Committee of the Twelfth International Geological Congress, with the assistance of geological surveys and mining geologists of different countries, published by: Morang & Co., Ltd., Toronto, Canada. Headquarters During Session at Toronto. The headquarters will be a t the University of Toronto, where there will be a branch post-office open at all hours and at which registered mail may be received or despatched, money orders sent or cashed, etc. A hank will be established at which money may be exchanged. A typewriting service will be maintained, also a telephone service and messenger service. Railway and steamship agents will also be in attendance. A restaurant service providing luncheon in the middle of the day will be arranged.

Jan 8, 1913

By Earl Bardwell

IN his paper entitled, Development of Hindered-Settling Apparatus, Dr. Richards has related the history of the development of the hindered-settling classifier and given illustrations of the several types of this apparatus which lie has designed.1 An earlier paper,2 Close Sizing Before Jigging, shows the nature of the hindered-settling phenomenon and the results which it produces. In the first-mentioned paper Dr. Richards describes the method of getting hindered settling and shows the relation that the constriction bears to the classifier. The question of proper ratios between the area of the sorting column and the area of the constriction opening Dr. Richards leaves open, aside from certain statements as to the ratios which have been found to give good results in practice. While working with a hindered-settling classifier of the type now in use at the Boston & Montana Reduction Plant of the Anaconda Copper Mining Co. a number of interesting facts were brought out which have thrown considerable light on the question of proper ratio between the area of the sorting column and the area of the constriction and which will be made the subject of this paper. Free and Hindered Settling. -If a, mineral particle be dropped into a vessel containing still water, the particle will sink in accordance with the laws of free settling in water, which are as follows: 1. Of two grains having the same specific gravity but differing in size, the larger will settle in still water at the greater velocity. 2. Of two grains having the same size but differing in specific gravity, the heavier grain will settle at the greater velocity.

Jan 8, 1913

By Edgar Dunn

PART I.-DETERMINATION OF GASES IN SMELTER FLUES. IN 1907, upon arriving in Anaconda to take up work in the testing department of the Washoe Reduction Works, the. following problem was met at the car step, so to speak: complete and. exact analysis of gases, not only at the stack, but also in all departmental flues. Taken up to employ time not otherwise needed for regular testing department work, instructions were extremely liberal for a commercial plant, to the effect that accuracy should not be sacrificed to speed. In December, 1907, the work was temporarily transferred to the Great Falls Smelter, and some of the methods here given were there worked out. Differences in smelting operations at Great Falls and Anaconda, however, necessitated further investigations and the development of a new method for S03 determinations at the latter plant, where work was resumed in July, 1908, and completed about a year later. At the time of inception of the work, data (not only on percentages, but even on methods) were found to be meager in the extreme, for one or the other of two reasons: either entire lack of experiment at a large proportion of smelters, or disinclination on the part of the managements to divulge data of any description pertaining to either results or methods. In making determinations of gaseous constituents of flues, two methods are open to consideration: 1, the drawing out of a sample, and collection of the same as a whole, to be removed to the laboratory for later analysis; and 2, the absorption in situ on the flue of one certain constituent, disregarding others for the time being, or perhaps combining two or three in one determination. The first is generally the more rapid, but it is also the more inaccurate, method of analysis, even with special type absorption apparatus, being the more largely subject to error, both of reading, and also because of leakage during complicated manipulation in the laboratory. The amount used for analysis must also, because of limit of container, be small for the first method, and an average gas is very seldom obtained, necessitating for a fair average result a large number of determinations. Consequently, when we balance the time spent in a dozen determinations of short-time samples as against the time employed in making two or three long-time determinations of various constituents in situ, we are not so certain in our statement as to the relative speed of the two methods. Moreover, the method of analysis in the laboratory of 100 cc. of flue gas is satisfactory only when constituents thus determined are present in considerable quantity, results being simply approximate when determining such compounds as sulphur dioxide, sulphur trioxide, carbon monoxide and dioxide, and arsenic trioxide and water vapor, none of which are carried in all smelter flues in amounts in excess of (or even approaching) 1 per cent by volume. Special condi-

Jan 8, 1913

By Max Hebgen

Within the State of Montana the streams rise in the high mountains at. an elevation of from 5,000 to 8,000 ft. These streams leave the State line both east and west at elevations from 3,500 to 2,400 ft. It is, therefore, apparent. that all these streams have an average fall of 3,000 ft. within the confines of the. State, and many opportunities are presented on all streams. for the development of power, by taking advantage of the natural fall. It is probable that 1,000,000 h. p. can :be developed in the State of Montana. I. NATURAL FEATURES OF STATE AFFECTING POWER DEVELOPMENT. The main. range of the Rocky mountains, forming the Continental Divide, cuts the State of Montana into two parts. The eastern part is drained by the Missouri river and its tributaries, the Madison; Jefferson, Gallatin and Yellowstone, rivers. The western part is drained by tributaries to the Columbia river, the Clarks fork and the Kootenai river. The Clarks fork in turn is formed by the junction of Missoula and Flathead rivers, the latter, draining Flathead lake. The western part of the State. is mountainous and the eastern part is comparatively level. As a natural result the rivers in the western part are capable of generating large amounts of power, while in the eastern part of the State natural power sites are much fewer and farther apart. It also follows that in the mountainous districts large amounts of power are required for the mining industry, while in the eastern part of the State, which is principally devoted to agriculture, power is required in smaller quantities. ?

Jan 8, 1913

By S. E. Bretherton

THIS title introduces the subject I wish to describe to my fellow members, very few of whom, I hope, have ever had as much trouble with the smelting of ore containing much zinc, either in the lead blast furnace or the matting furnace, its circumstances have forced upon me: First, for several years in Leadville, Colo., after the sulphide ores containing zinc had been developed with greater depth and were sold to the interests with which I was connected for smelting in the blast furnace for the recovery of the lead, silver, and gold; then, in New Mexico and Arizona, where the principal source of ore supply for our custom smelter was from miners who sent most of their product in the form of concentrates, which we briquetted and smelted in the blast. furnace, producing a matte containing copper, silver, and gold, for which we were paid; together with some zinc and lead, which was penalized if in excess of a maximum base set by the refinery to which we sold our copper matte; last, but not least, my experience in Shasta county, Cal., where for the sake of recovering $13 per ton value in copper, silver, and gold, I have smelted ore containing as high as 40 per cent. zinc (the last. 18,951 tons smelted averaged 15 3/10, per cent. zinc) which we not only lost, but which it cost us money to lose.

Jan 8, 1913

By C. W. Goodale

I. INTRODUCTION. In the summer of 1909 the Boston & Montana reduction department of the Anaconda Copper Mining Co. completed a new flue system, at a cost of about $1,100,000, and -is this includes the largest and highest chimney in the world, and some new features of flue construction, a description will be of interest. At the Spokane meeting of the Institute in September, 1909, a brief mention was made of this flue system, in discussing Mr. Brunton's presidential paper on the Progress of Metallurgy in the West, and a promise was given that when a long enough time had elapsed, so that operating results could be given, a paper would be offered. The smelting plant includes blast furnaces, MacDougall roasters, gas-fired reverberatories, and converters.

Jan 8, 1913