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The report of the Nominating Committee was presented and is given in this same Bulletin. A petition was received for new requirements for membership in the Institute and was ordered to take the statutory course. A petition was received for the establishment of a Tulsa Section of the Institute and was referred to a committee to report on the territory. Thirty-six Members, two Associates, and two Junior Members were elected. The status of two Junior Members was changed to Member.

Jan 12, 1917

A special war committee of the Engineering Council has been appointed to assist other committees of the United Engineering Societies having to do with the development of the arts and sciences related to warfare. One of the principal functions of this additional committee is to pass upon the probable value of new inventions. The new committee has established headquarters' in the rooms of the Naval Consulting Board in New York City, and has received the franking privilege of the Post Office Department.

Jan 1, 1918

By R. G. Fleck, W. R. Webb

The concentrate produced from the Adirondack magnetites is, of course, too fine for direct use in a blast furnace and must be agglomerated before it can be considered a blast furnace ore. The four operations in the area use sintering -three, including the Jones & Laughlin operation, employing the Dwight Lloyd continuous type machine and one operation using the Greenawalt batch type process. Each operation uses fine anthracite coal, either No. 4 or No. 5 buckwheat size, for the mix fuel.

Jan 6, 1950

By B. Barlin

Introduction The development of metallurgical practice at lambia Broken Hill is directly related to the change in mineralization of the deposits as mining progressed from the open pits to underground. The ore consists of a mixture of lead and zinc sulphide minerals, together with abundant silicates, carbonates and other oxidized minerals of these metals. The irregularity that characterizes the shape of the orebodies applies equally to their mineral content, which makes ore reserve calculations and the maintenance of a balanced feed to the metallurgical plants, problems of some magnitude. History The Rhodesia Broken Hill Development ,Company was formed in 1904 after an Australian prospector, T. G. Davey, discovered the outcrops in 1902. In the early years zinc ores were calcined for shipment but this proved uneconomic. Cerussite outcrops were then smelted directly in blast furnaces for the production of lead until 1929 when ore above the water level was exhausted.

Jan 1, 1970

By R. V. Ramani, T. S. Kovach

In many instances, the actual production from a longwall face does not equal the planned capacity. General problem areas that have been identified include face length and panel depth, face area and gate entry roof support, face conveyor and shearer wear, outby haulage system failures, number of entries in longwall gate development, and longwall move time. The performance of a longwall face is totally dependent on the interaction of these and other factors. To explore fully these interactions, a systems analysis of longwalls has been performed. In this paper, the systems approach, the factors considered in the analysis, and the results of the analysis are presented.

Jan 1, 1985

Percussion drilling with tungsten carbide insert button bits ranks among the most significant advances in both underground and surface drilling in medium and hard rock formations. Getting top performance and life from these upfront components is not particularly difficult if one pays attention to the basics in operation and maintenance. For some reason, a few of the essential operating and maintenance steps for getting the most from these tools seem to have gotten turned around; instead of operating at the near optimum levels, some miners, in following myths or misunderstandings about them, are shortchanging their optimal utilization. Let's examine the two most harmful ones.

Jan 8, 1978

By Robert Glass Cleland

THE BEGINNING of a large enterprise is often as in- significant as a lump of leaven hidden in a bowl of meal or a handful of mustard seed that the wind blows across a field. In 1950 the company known today as the Phelps Dodge Corporation had nearly thirty-two thousand stockholders, paid salaries and wages of about fifty million dollars to some thirteen thousand persons, produced nearly four hundred and ninety million pounds of copper, and possessed net current assets of approximately one hundred and six million dollars. For the origin of this great business, one must go back approximately a hundred and fifty years to an obscure saddle-making shop in the small town of Hart- ford, Connecticut. Anson Greene Phelps, proprietor of the shop and master saddler in his own right, was born in 1781-the year of the Battle of Yorktown, the surrender of Cornwallis, and the close of the Revolutionary War Anson's forebears had come to America in the great Puritan migration that left fields, shops, pulpits, and hearthstones in the reign of Charles the First to transplant the strong, tough roots of their race, culture, and institutions in the New World.

Jan 1, 1952

By Peter Kos

Since advances in the understanding of gravity thickening reflects the development of knowledge about suspensions themselves, the paper starts with the discussion of flocculent and nonflocculent suspensions. The properties of flocculent suspensions and their behavior in different concentration regions (zone settling, channelling, compression) are defined and discussed. In the main portion of the paper, the behavior of flocculent and nonflocculent suspensions during batch as well as continuous thickening, is presented, together with a brief review of the gravity thickening theories and sizing methods. The classical as well as the most recently developed methods are presented and their use and limitations are discussed.

Jan 1, 1980

By O. O. Laudig

It is a well-established fact that some ores do not reduce as readily in the furnace as others, thus seriously affecting out-put, and consequently, cost of product. With the object of obtain ing some information upon this subject, the following experi ments were made in the laboratory of the Buffalo Furnace Company. Efforts were made to obtain, as nearly as possible, represent ative ores from some of the most important mining districts in the United States. The ores received were from the Mesabi, Marquette, Gogebic, Menominee and Vermilion ranges of the Lake Superior district and from Southwest Virginia. Requests

Jan 1, 1897

By Arthur B. Emmons

HAVING been in the management of a company which has been exploring with a diamond drill during the past year in Rhode Island and Massachusetts, with a view to finding workable anthracite coal of a better quality than has been hitherto found, I have collected a certain amount of material which seems to have some scientific interest (though in this respect it is unfortunately incomplete), as well as a possible value to any one who may be tempted to follow ant a similar line of investigation. The following are the analyses of the coal from the Portsmouth

Jan 1, 1885

THE CHAIRMAN (DR. A. R. LEDOUX).-If there ever was a question in the mind of anybody as to whether there are some mining engineers, I think if they would look in the door tonight they would decide there are. We meet here tonight not only to enjoy a smoke and other incidentals which are permitted us in these days, but with a more serious thought in our minds, because that flag, with its 540 stars, only begins to show the number of our membership that are serving the country. We are thinking of them, and when we consider how many of those men are also citizens of one or another of our allied countries, we can imagine that many are tonight thinking of us and perhaps have received, even at the front, notices of our annual meeting and are wondering what we are doing tonight; so our thought this evening will be going out to them, going out to those of our number who are serving in the khaki or in the blue, or in other activities denied to some of us for one reason or another; but, gentlemen, there is one thing we will do now, we will rise and sing together r the Star Spangled Banner. Gentlemen, not only are American citizens here tonight, not only representatives of our country on the Speakers' platform, but. there are representatives of our Allies, and we are going to have the privilege of listening to one or two of the latter, a citizen of the great British Empire and a citizen of France. We will first have the pleasure of hearing Capt. Hodder-Williams. He has been loaned to us to take charge of training Columbia University students, after two years or more in the trenches, and lie carries with him the only German thing in this room, a German bullet in his shoulder. That has not affected either his spirit or his

Jan 4, 1918

By L. J. Erck, T. E. Ban

A discussion of laboratory procedures used to determine pellet quality and to simulate handling and firing conditions. Strength- temperature relationships in pelletizing; effect of chemical additives on agglomeration; and crushing, abrasion, and impact resistance of the pelletized products are discussed with respect to five different iron ore concentrates.

Jan 8, 1953

The Army Reorganization Act, which became effective July 1, 1916, contains a provision authorizing the organization of an Officers' Reserve, in which will be included a Corps of Reserve Engineers. There will also be an Enlisted Reserve of skilled workmen in technical lines. The special provisions of the bill relating to the Engineer Officers' Reserve were formulated with the help of the Joint Committee of the several national engineering societies, which has been at work on the matter for over a year with the War Department and Committees of Congress. Recognizing that engineering science is the basis of success in modern

Jan 8, 1916

G. R. GOHN. l-1n Table I11 of The Sager, Brown, and Mears paper, which was presented on the screen, data were given showing the results of accelerated corrosion tests of certain magnesium alloys. Mention was made that these were carried to a certain time which was used as a measure of failure but no mention was made as to the period of time. I would like enlightenment on that. G. F. SAGER (Author).-In reply to Mr. Gohn's question regarding the times of exposure for the accelerated stress-corrosion tests referred to in Table I11 of our paper, which shows the correlation between accelerated and atmospheric stress-corrosion tests on magnesium alloys, I can say that we usually run the accelerated tests on such alloys for at least 500 hr. We feel that this is long enough to reveal any marked susceptibility to stress-corrosion cracking. In the case of the atmospheric tests on such alloys, we have not yet decided how long we should expose the specimens. Most of them are being exposed for indefinite periods and a good many of our specimens have now been exposed for several years. We may want to continue some of the tests for five or ten years. The period of six months mentioned in connection with the times of exposure for the atmospheric specimens was a rather arbitrarily selected minimum time for which specimens had to be exposed before we counted them with those that had not failed. A fairly large number of magnesium- alloy specimens have been exposed in the atmospheric stress-corrosion tests at var-

Jan 1, 1945

PUGET SOUND LOCAL SECTION. Executive Committee. CHESTER F. LEE, Chair roan. C. R. CLAGHORN, Vice-Chairman. JOSEPH DANIELS, Secretary-Treasurer, University of Washington, Seattle, Wash. W. C. BUTLER. AL K. RODGERS. On the evening of Tuesday, Sept. 2, an informal dinner was held at the University Club, Seattle, Wash., at which the Secretary of the Institute was present, and a valuable and interesting conference took place concerning the recent activities of the Institute and the relations of the Institute management to the Local Sections. SOUTHERN CALIFORNIA LOCAL SECTION. Executive Committee. THEODORE B. COMSTOCK, Chairman SEELEY W. MUDD Vice-Chairman. FREDERICK J. H. MERRILL, Secretary-Treasurer, 300 Germain Building, Los Angeles, Cal. C. COLCOCK JONES. FRANK ROBBINS. Maintains headquarters at 300 Germain Building, Los Angeles, Members of the Institute are invited to visit these headquarters whenever they are in the city. A reception was held at the headquarters of the Section on Wednesday, Sept. 10, at 8 p.m., to meet the Secretary of the Institute and discuss Institute activities and affairs. Light refreshments were served, and about 20 members of the Section attended.

Jan 10, 1913

By Clarence Zener

Contents Page General Principles................................................................. 551 Equilibrium Diagrams......................................................... 551 Nucleation................................................................... 553 Kinetics of Phase-boundary Propagation......................................... 553 Kinetics of Growth of New Phase............................................... 556 Spheroidization............................................................... 560 Pure Iron-carbon System........................................................... 561 Formation of Pearlite.......................................................... 561 Interlamellar Spacing........................................................ 562 Pearlite C-curve............................................................. 563 Bainite Formation............................................................. 565 Formation of Martensite....................................................... 570 Loss of Tetragonality of Martensite.............................................. 570 Effect of Alloys upon Decomposition of Austenite..................................... 572 Pearlite...................................................................... 572 Bainite and Martensite......................................................... 574 Time-temperature-transformation Curves............................................. 576 Appendix A............................................................. ......... 579 Appendix B....................................................................... 580 Appendix C....................................................................... 580 The present investigation started in an attempt to understand certain details of the decomposition of austenite, and of the effect of alloying elements thereon. As the investigation proceeded it became apparent that not only these details, but all the general features of austenite decomposition, could be understood in terms of fundamental physical principles. Since the direct applicability of these physical principles has not been previously recognized, it was decided to incorporate the original results of the investigation into a review of the general subject of the kinetics of austenite decomposition. This review constitutes the present article. An extended summary of the results is given on pages 576 to 579. This article, which deals with the kinetics of phase transformations, may appropriately be considered as a sequel to two recent articles1,2 from this laboratory on the equilibrium relations in medium alloy steels.

Jan 1, 1947

By Clarence Zener

Contents Page General Principles................................................................. 551 Equilibrium Diagrams......................................................... 551 Nucleation................................................................... 553 Kinetics of Phase-boundary Propagation......................................... 553 Kinetics of Growth of New Phase............................................... 556 Spheroidization............................................................... 560 Pure Iron-carbon System........................................................... 561 Formation of Pearlite.......................................................... 561 Interlamellar Spacing........................................................ 562 Pearlite C-curve............................................................. 563 Bainite Formation............................................................. 565 Formation of Martensite....................................................... 570 Loss of Tetragonality of Martensite.............................................. 570 Effect of Alloys upon Decomposition of Austenite..................................... 572 Pearlite...................................................................... 572 Bainite and Martensite......................................................... 574 Time-temperature-transformation Curves............................................. 576 Appendix A............................................................. ......... 579 Appendix B....................................................................... 580 Appendix C....................................................................... 580 The present investigation started in an attempt to understand certain details of the decomposition of austenite, and of the effect of alloying elements thereon. As the investigation proceeded it became apparent that not only these details, but all the general features of austenite decomposition, could be understood in terms of fundamental physical principles. Since the direct applicability of these physical principles has not been previously recognized, it was decided to incorporate the original results of the investigation into a review of the general subject of the kinetics of austenite decomposition. This review constitutes the present article. An extended summary of the results is given on pages 576 to 579. This article, which deals with the kinetics of phase transformations, may appropriately be considered as a sequel to two recent articles1,2 from this laboratory on the equilibrium relations in medium alloy steels.

Jan 1, 1947

By R. C. Ellman

In the United States, the consumption of lignite and subbituminous coals is increasing. A variety of energy-oriented companies have leased large blocks of reserves, new large power plants are in operation and being constructed, and new producing mines are being developed. The Bureau of Mines has maintained an active interest in the utilization of low-rank coals for many years. In 1951, with the completion of the Bureau's Grand Forks Coal Research Laboratory, an organizational unit was established for studies in lignite preparation. Since that time, numerous investigations have been completed. This research has dealt almost exclusively with lignite, but since subbituminous coals have many similar characteristics, the findings can often be applied to both types of coal.

Jan 1, 1970

By S. F. Emmons

In a report upon the geology of Ledville and vicinity, which is till in the hands of the Public Printer, I hare given, at some length, my conclusions as to the genesis of the remarkable silver-lead deposits of that region, and the data, gathered during a long and careful consideration, upon which my views were founded. In the brief abstract of this report, published in 1881, the bare conclusions are given, with but few of the facts upon which they were founded. Since that time, these conclusions have been variously criticized, and it has even beer] assumed that the views I expressed with regard to these deposits were intended as a theory of ore-deposits in general.

Jan 1, 1887

By Harold R. Wampler, John L. Bolles, Adrian J. Broderick

Phelps Dodge's 60,000 tpd Morenci Concentrator has been in operation since 1942. The integrating of process control applications into the concentrator began in 1972. A process control system is presently on-line controlling 30 primary grinding circuits and all reagent additions. The system consists of a centralized control room process control Computer, on-stream X-ray analyzer, on-stream particle size analyzers and an operator interface. This paper describes the process control system's development, control concepts and its influence on the concentrator performance.

Jan 1, 1978