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The Arizona Committee, consisting of GERALD F. G. SHERMAN, Chairman, ARTHUR NOTMAN, Secretary, NORMAN CARMICHAEL, B. BRITTON GOTTSBERGER, W. L. CLARK, J. C. GREENWAY, W. G. MCBRIDE, FOREST RUTHERFORD, has arranged the following program for the Arizona Meeting, which has been approved by the President of the Institute and by the Executive Committee. It is printed herewith for the information of members, and probably will not be changed in any material respect. Sunday, September 17, 1916.-Arrive at El Paso, Texas, 2.40 P.M., leave 10.20 P.M. Monday, September 18, 1916.-Arrive at Deming, N. Mex., .12:47 A.M. Arrive at Santa Rita, N. Mex., 4.00 A.M., where luncheon will be served, after which there will be a visit to the Chino mines. From there the train will proceed to Hurley, N. Mex., where a visit will be made to the mill of the Chino Copper Co.

Jan 7, 1916

ABIDE from the John Fritz Medal, in which the Institute participates through its representation on the John Fritz Medal Board, the Institute itself has three major awards to make annually and one special prize for excellence in technical papers, as follows. The Robert W. Hunt Medal and Prize, The J. E. Johnson, Jr., Award, the James Douglas Medal, and The Lewisohn Platinum Prize to senior members. ROBERT W. HUNT MEDAL AND PRIZE The partners of Robert W. Hunt established a fund which was presented to the Institute at a fitting' ceremony on May 27, 1920, to establish an annual medal and a sum of money to be awarded under the following rules ? 1 The award shall consist of two prizes, first of a gold medal, second of a sum of money, a certificate to accompany each prize. The money prize shall not be awarded to a member over 40 years of age, but under unusual circumstances, both prizes may be allotted to one person provided that he is not over 40 years of age In general it will be understood that the Committee shall award the money prize to the younger men, rather than the medal. 2 The awards shall be made not oftener than once a year to that person or persons contributing to the Institute the best original paper or papers on iron and steel The scope of the term "iron and steel" shall be determined by the sub-committee considering the awards In general, papers dealing with the practical side of the subject have preference over those dealing with the theoretical side in recognition of the fact that Captain Hunt's main contributions to the industry have been in the improvement of production and quality of material

Jan 1, 1923

By P. J. Carroll, H. Colijn

Feeders must be considered an integral part of the over-all bin and feeder system. Improper design of either one of these parts will affect the performance of the whole system. Feeder load, material properties, feed rate, physical layout, and environment as well as first cost determine the selection of feeder type. This paper provides a new method of calculating feeder loads with some experimental data as verification. General design criteria for belt and apron feeder, rotary table and plow feeders are discussed and a special section is devoted to vibratory feeders. Feeders are used to provide a means of control for the withdrawal of bulk materials from storage units such as bins, bunkers, silos and hoppers. This control function can only be performed properly as long as the bulk materials flow by gravity to the feeder in a uniform and uninterrupted fashion. During the past few years various papers have been written and presented on feeders and their application.1-9 This paper will be confined to some specific bin-feeder design criteria such as feeder load and power requirements. Special attention is given to the basic design criteria for vibratory feeders. HOPPER AND BIN DESIGN Feeders must be considered an integral part of the over-all bin and feeder system. Improper design of either one of these parts will affect the performance of the whole system. A lot of effort has been devoted in the past decade to the development of functional design criteria for hoppers and bins.1,10 The integrated concept of bin and feeder design requires quantitative analysis of the bulk material characteristics before the design and the selection of components can be attempted. The design of a feeder system must begin with the proper dimensioning of the hopper outlet to prevent arching or ratholing. The hopper opening should be large enough to allow passage of the bulk solid at the required maximum discharge rate." A feeder can only throttle the flow. FEEDER LOAD DETERMINATION Over the past ten years, there have been various attempts to determine the exact load or pressure on feeders mounted directly under hopper openings. Many designers, however, still consider this pressure equal to the hydrostatic head of material above the opening, and because such pressure would be very

Jan 1, 1969

By John Jermain Porter

PAGE. I. INtroduction............ 191 I1. Derivation of Formula foR Fuel-RequiRements.... 192 1. Heat Available in the Hearth........193 a. Method of Calculation..193 b. Data for the Determination of Critical Temperature.. 195 2. Heat Necessary in the Hearth ...... 197 a. To Care for Slag..197 b. To Care for Pig-Iron...198 c. To Reduce Silicon........198 d. For Other Items.........199 3. The Effects of Rate of Driving ..... 199 4. Loss of Carbon Between Throat and Hearth.....201 a. Solubility of Coke..201 b. Carbon-Loss Due to Flux....201 c. Effects of Reducibility of Ore..202 5. The Formula as Used........203 III. The LImitations of the Formula........ 204 1. Through Effects of Irregular Furnace-Work.....204 2. Through Ratio Between Heat-Requirements in Shaft and Hearth. 20.5 IV. The Formula Applied to Actual Furnace-Records,.. 209 1. Description of Furnace-Stock........ 209 2. Furnace Dam..........210 3. Application of Formula..211 4. Average Furnace-Practice..213 V. Sources of Error........... 214 VI. SuggesTions for Practical Methods of Fuel-Economy... 215 VII. Efficiency as a Factor in Furnace-Management.... 219 1. The Efficiency Principle........ 219 2. The Application to the Blast-Furnace..220 I. Introduction. The heat-balance of the blast-furnace has been a favorite subject for discussion for many years. and its study has contributed much to our knowledge. and still possesses a certain academic interest. As a means of accounting for differences in fuel-consumption, however. it has failed utterly. and it is evident that we must look elsewhere for the means of accomplishing this end.

Jan 1, 1912

By Raymond Mancha

THE purpose of the Coal Division's Committee on Ventilation is to cover one principal aspect of mine ventilation thoroughly each year, instead of attempting to touch upon several different subjects. The Committee for 1943 consists of four members besides the Chairman. Members, selected because of both knowledge of the current topic of mine ventilation, and diversity of occupation, are: Carel Robinson, consulting engineer with an operating background; T. G. Fear, chief engineer for the Hanna Coal Co., an operator of varied experience in mine ventilation; E. H. Denny, chief of the coal mine inspection division of the U. S. Bureau of Mines, obviously well qualified; and C. M. Smith, editor of Mechanization with a background of mine ventilation study as a member of the mining department of the University of Illinois, at present retained as a ventilation consultant by the Climax. Molybdenum Co. of Climax, Colo.

Jan 1, 1944

By R. F. Miller

DUE to wartime secrecy restrictions a large part of the technical information developed by government and industrial laboratories was withheld from distribution. Much of this information has now been released or "declassified" and reports of technical work carried out during the war in allied and enemy countries are also becoming available. Information on the latter subject has been augmented by the work of the Technical Industrial Intelligence Corps of the U. S. Army. Through the Joint Chiefs of Staff, rep¬resentatives of this Corps co-operated with the British Combined Intelligence Observations Subcommittee, and some of the observations were made by combined personnel of both groups. The U. S. Government has undertaken the indexing and abstracting of all of this information in the Bibliography of Scientific and Industrial Reports, a weekly bulletin which appeared first early in 1946. Other publications, such as the Bulletin of the British Iron and Steel Institute and The Metals Review of the American Society for Metals, provide abstracts of domestic and foreign magazine articles and papers presented to technical societies. However, they do not cover the industrial and government reports recently released by the Government nor the reports of the Army investigators hence the new bibliography is a welcome addition to our metallurgical library.

Jan 1, 1947

By Russell B. Cornell, William B. Plank

AT the close of the academic year 1940-'41 the largest number of students ever recorded received their first or bachelor degree in the mineral technology schools of the United States. The total of men thus prepared to enter their professional careers in the mineral industries was 1601, a number nearly 12 per cent larger than two years ago and nearly 75 per cent larger than four years ago. Notwithstanding this increase in the number of graduates and as had been predicted in the preliminary report in February, there was a slight decrease in the total student population of the schools in both the United States and Canada. During the college year 1940-'41, 9133 students were enrolled in the 54 schools of the United States and 764 in six of the seven schools of Canada.

Jan 1, 1941

By Max Boehmer

(Pittsburg Meeting, March, 1910.) AFTER 30 years of development and after an output of $350,000,000 in value of gold, silver, lead, zinc, and copper, there has not been published a satisfactory explanation of the origin of the immense deposits of the Leadville district. The original examination find survey of Leadville by members of the U. S. Geological Survey was a most magnificent piece of work, but their attempt to explain the origin of the ores was based upon the then-accepted theory of lateral secretion, originated by Sandberger, which theory was afterwards disproved in many cases by further development in numerous districts. This theory contended that the ore in the veins had been leached by surface-waters from the eruptive rocks in the immediate vicinity, and it had its origin in the fact that the neighboring eruptive rocks all contained, to an appreciable degree, the several metals found in the ore-deposits. But the practical miner, reasoning in a simple manner from the condition of things as he found them underground, soon discovered the fallacy of this proposition. He reasoned that, in the case of the Leadville deposits, this theory could not be true, because, if the ores were leached from the overlying eruptive rocks by surface-waters, they would as a matter of necessity be controlled by the action of gravity, and the main bodies would collect in- natural depressions of the underlying limestone, and at all points where such depressions existed. But this was not in accord with the channels of ore as he found there ; and hence the theory of lateral secretion in this district was never accepted. Another objection to it consisted in the fact that large areas within the ore-bearing district contained no ores whatever, although their formation was the same, and the same limestones were covered by the same thick sheet of

Feb 1, 1910

By John Birkinbine

In the belief that a resume of what will be exhibited during this meeting, and a brief record of progress in the seven years which have elapsed since the Institute's first visit to Lake Superior would be interesting, the following statistical data have been prepared or copied from the most reliable sources, and considerations are also presented concerning the development or utilization of some of the resources of the Lake Superior Region. When the Institute, on the return trip from enjoying the charming panoramas of Thunder Cape or Isle Royale, and inspecting the unique development of Silver Islet, passed, in August, 1880, through the St. Mary's Falls ship canal, en route to Escanaba, the boat was lowered from the level of Lake Superior to that of Michigan and Huron lakes (18 feet), through two locks each 70 feet wide and 350 feet long, which had been in use since 1855. But as these locks accommodated vessels which drew 12 feet of water or less, a new lock 80 feet wide, 515 feet long and admitting vessels of 16 feet draught was approaching completion and was opened in September, 1881. The time required to pass the locks was utilized by the members in examining the work upon this new lock and in viewing the Sault Ste. Marie, which in discharging from Lake Superior all average volume of 90,783 cubic feet of water per second, forms a rapid, falling 18 feet in one mile. But the lake traffic through the St. Mary's ship-canal has developed so rapidly that another and larger lock is now required, and work has been commenced by the

Jan 1, 1888

Many of those who attended the meeting at Chicago spent the first part of the following week in Pittsburgh, when the Experiment Station of the Bureau of Mines was dedicated and the fourth annual First Aid and Mine Rescue Contests were, held. The Bureau buildings were open for inspection during the three days, Monday, Tuesday, and Wednesday. The dedicatory ceremonies were held in the Bureau of Mines main building, Monday morning, Sept. 29, Mr. T. J. Gillespie, representing the Pittsburgh Chamber of Commerce, presiding. In his address of welcome, Hon. E. V. Babcock, Mayor of Pittsburgh, said: "The reclamation work already done stands out conspicuously beneficial to industry and populace alike all over the United States. It has demonstrated methods of preservation of life and reclaiming of injured persons which are new and greatly beneficial to modern civiliza-tion. The establishment of this institution in Pittsburgh was greatly desired, and now it is here it is greatly appreciated." The response was given by First-Assistant Secretary of the Interior Vogelsang, who represented Secretary Franklin K. Lane. He said that the Bureau of Mines did more during the war for the triumph of American arms than any other institution.

Jan 11, 1919

By E. J. Fasiska, L. Zwell

PREVIOUS investigations 1,2 of Fe3P described by pearson3 and schubert4 show that Fe3P has a bct unit cell having four Fe3P tetrahedra centered around each lattice point. The space group is 14, No. 82, and all atoms occupy general positions 8(g). The cell dimensions3 are: a = 9.090, c = 4.446 kX, with an axial ratio of c/o = 0.4891. We have measured the lattice parameters of Fe3P, using a Fe as an internal temperature standard, at 23°, 414°, and 678°C and computed the thermal expansion over this temperature range. The Fe,P was prepared by melting under vacuum (after flushing with argon) a commercially pure iron and "ferrophosphor" in a high-frequency induction furnace. Part of the ingot was crushed for X-ray examination and for chemical analysis. X-ray diffraction and light microscopy indicated iron phosphide (Fe3P) present as the major constituent and a small amount (about 5 pct) of a Fe. Chemical analysis showed 0.05 wt pct Si, 0.008 wt pct N, 0.018 wt pet C, and less than 0.02 wt pct each of other metallic elements. X-ray diffraction powder patterns were obtained from a mixture of iron and Fe3P sealed in an evacuated quartz capsule using a Unicam high-temperature

Jan 1, 1968

By WALTER S.

(New York Meeting, February, 1912,) THE earliest example of attempting to form finely-divided materials into larger masses for better adaptation to commercial use was probably the briquetting of peat and lignite-waste at Paris by the use of a clay binder. It was from this attempt that our word briquette has arisen (Fr. la brique), the formed masses being shaped similar to ordinary bricks. This term does not, however, lend itself to the many shapes of such formed material as are now being produced, as few of them aside from some of the European brown-coal products bear any resemblance to the shape of that well-known article. The term "agglomeration " has therefore been chosen as more accurately descriptive of the products now being manufactured, this term including the molding as well as the sintering. With the increasing prices of fuel and ores and the greater demand for economy in the operation of industrial plants, more ,attention has been paid in recent years to the utilization of waste products and low-grade ores and fuels. Much of the waste has been occasioned by the inability to utilize finely ,divided ores and fuels in the furnaces because they could not be kept there, or else because they clogged up the furnace-shaft so that gases could not be forced through under ordinary conditions of operation. As a result, all such fines were thrown on the dump. Again, with the exhaustion of the richer deposits of ores, concentration of lower-grade ores becomes a necessity, and most concentrates are produced in a finely-divided condition. Aside from these considerations, there is also the economy in the cost of operating the plant; a furnace running on agglomerated material will have a much greater output than one working on fines. In one instance the charge of an iron blast-furnace was changed from fine concentrates to briquettes and the output was increased four-fold; better results could have been obtained had facilities been at hand for taking care of the increased output.

May 1, 1912

By C. E. Birchenall, G. Derge

IN studying the kinetics of slag-metal reactions, it has become increasingly apparent that a complete knowledge of all aspects of interface phenomena will be required to clarify these processes adequately. A part of the data required for all oxidizing slags used in the refining of impure iron to steel is the rate of exchange of iron between the slag and metal phases. The simplest equilibrium of this type is that between liquid iron and iron silicate slag when both phases are equilibrated with the silica crucible containing them. In this study, the exchange of iron between the two liquid phases has been measured by using radioactive Fe as tracer. The observed high exchange rate indicates the ease with which such interfaces may be crossed in refining processes. The experiments required for this study involved relatively minor and normal modifications of well established techniques. Melting was accomplished by induction heating in heavy walled, fused silica, rotating crucibles." Rotation was used to minimize dilution of the slag by crucible erosion. The melting stock was ingot iron. Slags were prefused in iron crucibles using chemically pure grade oxide reagents. The special conditions applying to the active iron additions will be described for individual experiments. Suitable precautions were observed with regard to protection against radiation hazards.' Identification of Activity This particular study was initiated several years ago, but held in abeyance because the radioactive iron available at that time contained a foreign activity which concentrated in the slag so as to mask the iron activity and render the results unin-terpretable. With the benefit of experiences from other studies, radioiron of suitable purity can now be prepared. As received from the Isotope Div. of A.E.C., the unit appears to contain Fe + Fe50 and a high activity cobalt. The cobalt and iron are separated by repeated ether extractions, and the purified iron stored for sufficient time for the Fe'7 44 day half-life) to decay to negligible activity, leaving only Fe as the active isotope. This was confirmed by the absorption curves for slag and metal samples from heat No. 1. In Fig. 1 the experimentally measured points for the absorption curves of slag and metal are fitted by the calculated slope of 5.8 mg per sq cm in aluminum, which corresponds to the Mn K doublet emission resulting from the capture of an orbital electron of Fe" by the nucleus. This shows that the radioactive species are the same in both slag and metal and identifies it as Fe55 Description of Individual Heats For the first heat, the radioactive iron was contained in the prefused slag. The active Fe55 had been precipitated with carrier and was added as Fe2O3 during fusion in the iron crucible. The charge of 500 grams of ingot iron was melted, the protective iron sleeve added, rotation started, and a prefused, inactive slag was added to allow the system to approach equilibrium. After about 5 min at temperature, the wash slag was skimmed and the active slag added. Initial slag and metal samples were taken as soon as the slag was molten. Additional samples were taken at indicated intervals thereafter. Slag samples were dipped with a small iron spoon and metal samples were sucked into 1/4 in. ID silica tubes. The slag and metal samples were pulverized and mounted for radioactive counting. The slag samples were analyzed chemically for FeO. Temperature was read after the last slag sample by immersion of a Pt-Pt-Rh thermocouple protected by a fused silica sheath. Since no significant variation of rate with temperature was observed

Jan 1, 1954

Edward Eeller, Baltimore, Md. (communication to the Secretary): Mr. Miller's improved method of the cyanide-assay for copper will, without doubt, be much appreciated by assayers and chemists who are engaged at copper mines and works. The writer, as one who, at one time, had much work of that kind to do, entertains no doubt of its practical value. In enumerating the factors which affect the accuracy of cyanide-titration, Mr. Miller omits to mention time. This I have always considered an essential one; i.e., in order to secure accuracy, I have believed it to be necessary to run the cyanidesolution at the same rate of speed in standardizing as in the titration of the samples. I have accomplished this, without the use of a time-keeper and without noticing the volume of the solution, in the following simple manner: In running the cyanide-solution from the burette, the stream was so regulated, by manipulation of the cock, that it retained its continuity for a distance of about one inch below the orifice, and, below that, broke into individual drops. This means that a constant pressure is maintained at the orifice of the burette, so that, during equal intervals of time, equal volumes of the solution pass through. The stream of cyanide-solution was left to flow in the manner indicated until the blue ammoniacal copper-solution began to show a distinct change in color, after which the cyanide was added by drops at regular intervals until the desired end-reaction. When several burettes are used they should have orifices of equal diameter; otherwise, the timefactor must be considered separately for each. In accordance with Mr. Miller's views, I have always considered the cyanide-method as of very satisfactory accuracy for all copper-assaying in which I did not employ the electrolytic method. It may interest some of my colleagues to know the modified method which I employed some fifteen years ago in making great numbers of copper-estimations on ores and

Jan 1, 1902

By Frederic P. Dewey

THE Bureau of the Mint of the United States Treasury maintains 13 offices for the purchase of gold-bullion, and this paper describes an investigation to establish the reasonable differences in the assay-results at the various institutions which may be commercially allowable in the settlements between them. Beginning with the comparative assay of proof-gold at the Philadelphia mint and the Utrecht mint, which shows 0.00002 as the closest agreement now possible, eight tables of comparative results, taken from the regular work of the service, are given. These tables begin with very fine gold, produced in an electrolytic refinery, showing close agreement. in the assay-results, and follow through decreasing gold fineness and . increasing amounts and complexity of base metals to very impure and complex bars produced at cyanide-mills, some of which give widely-varying results. Next is given a series of results on samples, prepared and sent out to various laboratories in the service, to test the influence of different metals and various combinations upon the' agreement of the assay-results; 11 samples were sent out and each one was assayed from 44 to 71 times, making a total of 623 assays. To these are added 107 assays of identical samples of coin-gold. On a previous occasion,' I have endeavored to show the degree of accuracy that may be expected in the ordinary everyday analysis of various materials, and on another occasion2 I

Aug 1, 1909

By John K. Kennedy

ThE basic equations describing continuous zone-melting via the zone-void method were reported by Pfann. Using these equations, a theoretical study was undertaken in this laboratory on the effect of the variation of the significant parameters of the zone-void system. These parameters are the zone length, 1, the heater length, h, and the effective distribution coefficient, k. The object of this study was to determine the effect of these parameters on and (where a = Cp/Cf and ß = Cw/Cf, Cp, C,, and Cf being, respectively, the solute concentration in product, waste, and feed) so that, in future application of this technique to the ultrapurification of materials, the effect of 1 and h would be predictable regardless of the value of k. The basic assumptions made by pfannl were, for the purposes of this study, assumed to hold. For k < 1, the steady-state solute distribution in the stripping section and the shift in this distribution brought about by passage of a void is shown in Fig. 7 of Ref. 1. In this section the definition of k and ß precludes the possibility of ß assuming values less than unity when k < 1. In the course of this investigation it was found that computations based on Pfann&apos;s equations gave values of ß less than unity in the region 1 > k > l/h for almost all values of Ls, where Further computations showed that 6 assumes negative values when k > 1 for many values of L,, 1, and h. A check of the derivation of the stripping-section equations showed that an error had been

Jan 1, 1964

By Edmund C. Pechin

The Lucy furnace, owned by Messrs. Carnegie, Kloman & Co., and located on the Alleghany River, on the outskirts of Pittsburgh, is a splendid modern furnace, 75 feet high, and 20 feet bosh. She had been working well on low grade ores of about 50 per cent., producing daily 68 to 75 tons. There was on stock 500 tons of Republic ore, one of the purest and best of the Lake Superior ores, averaging over 68 per cent. of iron, which had been procured for the purpose of making a trial for Bessemer iron. This was charged by itself, and Mr. Skelding, the founder, reports that he did not succeed in getting a single cast when it came down, before the furnace chilled from the hearth to the top of the boshes, some 25 feet. Every effort was made to save her, without avail, and the disagree-

By George Lehman

THE Inspiration Consolidated Copper Co. had an orebody at Miami, Ariz., of close to 100,000,000 tons of low-grade copper ore, and the method of mining this ore most profitably was of great importance. The selection of a method was practically limited to a "top-slicing," a "shrinkage-stope" or a "caving" method. The "top-slicing" method would give a high extraction of the developed ore, at a high mining cost, and the ?shrinkage-stope" or "caving" methods ) a lower extraction of, the developed ore, at a lower mining cost. ORE-DRAWING TESTS To decide on the method to be used it was necessary to know about what extraction of the ore could be obtained by the "shrinkage-stope" or "caving" methods. As no definite information regarding the question was available at the time, C. E. Mills, the general manager, thought that some information could be obtained by experimenting in drawing ore, covered with capping, from an experimental box. Some work had already been done along these lines by W. C. Browning for the Inspiration Copper Co. and by myself for the Live Oak Development Co. The idea was to represent as nearly as possible, in the experimental box, the conditions within an area of caved stopes of caved ore all ready for drawing. That is, the area was supposed to represent a semibroken mass with the capping above it in the same condition and ready to follow the ore downward as it was drawn out of the chutes under the ore. To represent the above condition, in the experimental box, crushed ore from the mine was placed in it to a given height, and red barren capping from the mine was placed on top of the ore.

Jan 9, 1916

By E. C. Pechin

THE Lucy furnace, owned by Messrs. Carnegie, Kloman & Co., and located on the Alleghany River, on the outskirts of Pittsburgh, is a splendid modern furnace, 75 feet high, and 20 feet bosh. She had been working well on low grade ores of about 50 per cent., producing daily 68 to 75 tons. There was on stock 500 tons of Republic ore, one of the purest and best of the Lake Superior ores, averaging over 68 per cent. of iron, which had been procured for the purpose of making a trial for Bessemer iron. This was charged by itself, and Mr. Skelding, the founder, reports that he did not succeed in getting a single cast when it came down, before the furnace chilled from the hearth to the top of the boshes, some 25 feet. Every effort was made to save her, without avail, and the disagree-

Jan 1, 1874

Members of the American Institute of Mining and Metallurgica Engineers can now secure copies of the Journal of the Institute of Metals of Great Britain at a special price of $5 for the two volumes issued during the year, postage extra amounting to approximately 25 cents. This Journal is one of the best books dealing with the subject of non-ferrous metals and alloys and this arrangement with the Institute of Metals permits our members to take advantage of this specially low price. Back numbers of the Journal can be purchased on the same basis. The Journal can be ordered directly through the office of the Institute of Metals, Great Britain 36 Victoria St., Westminster, S. W. I., London, England. The letter should be accompanied by an international money order and a copy sent to Secretary of the A. I. M. E. in order that the membership record may be checked.

Jan 9, 1919