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By E. A. Holbrook

AT the meeting of the Committee on Engineering A Education of the Institute at the New York meeting last February, it was brought out that the number of men graduating in mining engineering from our colleges at the present time is not sufficient to meet the ordinary needs of the mineral industries. Following the meeting, Samuel S. Wyer, consulting engineer of the Fuel-Power Transportation Educational Foundation of Columbus, Ohio, prepared a pamphlet called "Mining Engineering's Appeal to High School Seniors." Under the auspices of this Foundation the pamphlet is being sent to every high school in the United States. The pamphlet does not in any way paint glowing word pictures of the profession; rather it is a statement of the importance of mining engineering in our present-day civilization, together with the requirements in young men who are looking forward to an engineering career.

Jan 1, 1930

By Thomas V. Falkie, Robert Stefanko

Recently The Wall Street Journal featured a series of articles titled "The Dirty Work-Brutal, Mindless Labor Remains a Daily Reality for Millions in The US.-Mining Coal, Shoveling Slag, Gutting Hogs Pays Bills But Can Drain Spirit, Hope." The article was devoted to describing how tough and dangerous is mining (and some other jobs) and how rough life is for miners and their families. Similarly during the past few years some psychiatrists and sociologists have devoted increased attention to the attitudes and life styles of miners. Unfortunately most of their approaches have been neither scientific nor objective, and very little good clinical research has been done on the subject.

Jan 1, 1971

By AIME AIME

TWO weeks ago the writer was lunching in the Engineers` Club in New York with a man who has perhaps the widest acquaintance among engineers of anyone in the country a member of another of the Founder engineering societies. "By the way," lie asked. "who have they nominated for your next president."' "Doctor Becket," I told him- "Oh. that's line," he replied, in a heartfelt tone that rang with sincerity. "I have come in contact with him occasionally and he is just the right type.' And that is the way Dr. Frederick M. Becket impresses everybody. The right type. Most Institute members of the western group of hard-rock minors do not know him, but then they meet him in his swing around the circle next year they will not require a long acquaintance to sense his kindly and outstanding personality, to realize that he is a gentleman in the bet meaning o1 that word, a man of wide sympathies and interests.

Jan 1, 1932

By V.K. Zworykin

Throughout its development the science of electronics, like so many other branches of science and industry, has been indebted to the metallurgist. Metallurgy has provided the electronic engineer with conductors to furnish passage for electrons outside of his evacuated tubes: it has developed tungsten and tantalum wires for emitting electrons and various refractory metals and alloys suitable for electrodes, which receive them and guide them within the tube; finally it has supplied ferromagnetic materials both for shielding electronic apparatus from magnetic fields and for forming highly concentrated fields for deflecting electron . Today I hope to show you that electronics has not been altogether ungrateful for this assistance. More specifically, I wish to indicate the role that the electron microscope, a relatively recent product of electronic engineering, is playing even now in the study of metals. Every metallographer is aware that his standard metallographic microscope will not reveal structural detail involving separations smaller than a certain fraction —at the very best a tenth—of a micron. This limitation, he knows, is a consequence of the fact that the wave length of the light employed for forming the image has this order of magnitude. It is, thus, a property of all light microscopes. TO overcome it, a different imaging medium must be employed, The existence of such a medium became evident when it was demonstrated1 that electrons were affected by magnetic and electric fields with axial symmetry just as light is affected by glass lenses; these fields, or "electron lenses," curve the paths of electrons reaching them from an object located on the axis of symmetry in such a manner that, at some distance from the lens, a true image of the object is formed. Furthermore, although a wave length may . be ascribed to electron beams just as to light, this wave length is much shorter; for electrons accelerated through a difference of potential of 50 kilovolts, the wave length is only about one hundred-thousandth of that of visible light. Actually, the elcctron microscopes of today resolve detail one hundred times as fine as light microscopes; if the maximum useful magnification of the latter is taken to be a thousand, that of electron microscopes is one hundred thousand. The Electron Microscope Since electrons are readily scattered and absorbed by matter, specimens to be observed in the electron microscope must be prepared to be less than one micron in thickness; furthermore, the interior of the microscope must be carefully evacuated to prevent collisions between the clectrons and the molecules of the air. Finally, as already mentioned, the lenses are formed by axially symmetric magnetic or electric fields, and not by any material medium such as glass. Apart from these basic differences, the electron microscope closely

Jan 1, 1943

By V. K. Zworykin

Throughout its development the science of electronics, like so many other branches of science and industry, has been indebted to the metallurgist. Metallurgy has provided the electronic engineer with conductors to furnish passage for electrons outside of his evacuated tubes: it has developed tungsten and tantalum wires for emitting electrons and various refractory metals and alloys suitable for electrodes, which receive them and guide them within the tube; finally it has supplied ferromagnetic materials both for shielding electronic apparatus from magnetic fields and for forming highly concentrated fields for deflecting electron . Today I hope to show you that electronics has not been altogether ungrateful for this assistance. More specifically, I wish to indicate the role that the electron microscope, a relatively recent product of electronic engineering, is playing even now in the study of metals. Every metallographer is aware that his standard metallographic microscope will not reveal structural detail involving separations smaller than a certain fraction —at the very best a tenth—of a micron. This limitation, he knows, is a consequence of the fact that the wave length of the light employed for forming the image has this order of magnitude. It is, thus, a property of all light microscopes. TO overcome it, a different imaging medium must be employed, The existence of such a medium became evident when it was demonstrated1 that electrons were affected by magnetic and electric fields with axial symmetry just as light is affected by glass lenses; these fields, or "electron lenses," curve the paths of electrons reaching them from an object located on the axis of symmetry in such a manner that, at some distance from the lens, a true image of the object is formed. Furthermore, although a wave length may . be ascribed to electron beams just as to light, this wave length is much shorter; for electrons accelerated through a difference of potential of 50 kilovolts, the wave length is only about one hundred-thousandth of that of visible light. Actually, the elcctron microscopes of today resolve detail one hundred times as fine as light microscopes; if the maximum useful magnification of the latter is taken to be a thousand, that of electron microscopes is one hundred thousand. The Electron Microscope Since electrons are readily scattered and absorbed by matter, specimens to be observed in the electron microscope must be prepared to be less than one micron in thickness; furthermore, the interior of the microscope must be carefully evacuated to prevent collisions between the clectrons and the molecules of the air. Finally, as already mentioned, the lenses are formed by axially symmetric magnetic or electric fields, and not by any material medium such as glass. Apart from these basic differences, the electron microscope closely

Jan 1, 1943

By H. Y. Bassett

THIS paper attempts to show the various major operations used in nonferrous tube mills and does not necessarily represent the current practices at the two plants of the Wolverine Tube Div., of Calumet and Hecla Consolidated Copper Co. Inc. The operations now utilized in the production of tubing are quite varied and show the continual interest and advance metallurgically and mechanically to produce the best quality at the lowest cost. Naturally, any advance or lowering of cost is dependent on large production runs, which mean longer machine running time with maximum worker productivity. Standardization of tube sizes and elimination of unnecessary alloys are therefore very necessary, otherwise the development of costly new production machines would be of little benefit to the consumer as a whole. It should be noted that in such a short presentation it is impossible to describe in any detail the major operations. The short descriptions, it is hoped, will enable all who are interested to obtain a general idea of present, day practices in the copper tube producing field. Fig. I is a flowchart or sequence of operations showing the steps usually employed in tube production. RAW MATERIALS Quality starts with the raw material, and it is absolutely necessary that raw material be controlled and held to rigid specifications. Little need be said, however, regarding the raw materials for the casting of bars or billets, as the material always is purchased and checked against the various governing A.S.T.M. specifications. CASTING Casting, as is indicated in Fig. I, is quite varied and for convenience can be classified into two groups: The casting of solid billets, and the casting of hollow tubes, each of which is the base for subsequent operations. In the melting of the raw materials various types of furnaces are used, and the selection of any one is dependent on many factors outside the scope of this paper. However, as of general interest, a short description will be made of each. Induction Furnace (Low Frequency) This is popular in the melting of copper-base alloys, Fig. 2. In the induction furnace the principle of an inefficient transformer is used for the production of the necessary melting heat. The primary coil is.arranged around a transformer core made of high permeability silicon steel sheet. The secondary circuit is through a melting channel around the primary coil and opens into a hearth which contains the main charge. The heat is generated only in the melting channel, but because of the stirring action there is a constant flow of metal around the channel, which when mixing with the charge causes very rapid melting. The volatilization losses are very low as the furnace atmosphere above the charge is heated only by the heat from the melting metal. The stirring action, however, makes the use of any slag cover difficult. Such furnaces- must be started with molten

Jan 1, 1951

By G. G. Brown

Enthalpy-entropy diagrams are presented for natural gases of 0.6, 0.7, 0.8, 0.9, and 1.0 gravity over the pressure range of 5 to 10,000 Ib. per sq. in. and temperature range of 32º to 700°F. The charts indicate directly the work requirement and temperature rise for adiabatic compression or temperature change for free emansion of natural eases. Computation and Uses of Charts The Mollier diagram (Fig. 4), in which the enthalpy (heat content) is plotted against the entropy with lines of constant temperature, pressure,, and in some cases volume, has been found most convenient when dealing with the compression, expansion, and flow of fluids. In dealing with the flow of fluids, the sum of the increase in the enthalpy, AH, plus the increase in kinetic energy, AM —, plus the increase in potential energy, ?MZ, representing the total increase in energy of the fluid in flow, is equal to the sum of the heat q, and work added, —w, to the fluid while flowing between the entrance and exit of the flow system. AH + AM— + ?MZ = q-w [1] In cases where there is no significant change in potential energy or in kinetic energy (velocity), it follows that the increase in enthalpy is equal to the total energy supplied to the fluid. Under such conditions' the changes in the property of the fluid as it flows through a throttling valve, choke, or any other similar arrangement, may be read directly from the enthalpy-entropy diagram by following a horizolltal line between the known pressures' When compressing Or expanding a gas by means of a Or or engine in which no heat is added to or subtracted from the gas, but only work done, the changes in the properties of the gas may be determined along a vertical line of constant entropy between the entering and exit pressures. The power required for the compression of the gas may be readily determined by converting the increase in enthalpy into the desired units. The enthalpy-entropy diagram for natural gases is to the gas engineer what the steam diagram is to the steam-power engineer. For this reason it would be extremely convenient if a reasonably satisfactory enthalpy-entropy diagram could be prepared as a function of the gravity of the gas. A careful study of the known properties of natural gas indicate that this is possible. The effect of temperature upon the enthalpy at constant pressure is expressed as the "heat capacity" or "specific heat" of the gas. The best available data for natural and petroleum refinery gases indicates the relationship shown in Fig. I. From this it is clear that the specific heat of natural gases is a function only of the gas gravity and the temperature at atmospheric pressure. The effect of pressure on the enthalpy of natural gases is dependent upon the pressure-volume-temperature relationships,

Jan 1, 1945

By R. S. Shoemaker, R. M. Darrah

Expanded markets for copper in the past few years and a consequent search for new ore bodies have revitalized the widely known but seldom applied method of producing copper called heap leaching. Heap leaching is defined here as the process applied to oxide ores which have been mined solely for the purpose of leaching. In this case, all costs of mining the ore become a part (and a substantial one, as will be shown) of the cost of the copper produced, whereas in dump leaching the mining cost has already been accounted for as a stripping cost for the sulfide ore. Of course, with newly opened ore bodies, stripping costs may be divided through accounting procedures, between the copper produced by the mill and that obtained by leaching, but in general this type of operation must be economic on the basis of the sulfide ore alone. Heap Leaching Requires Low Capitalization Heap leaching, as a beneficiation method, is unique in that it is the only process used for the recovery of a metal in which the time involved from mining the ore to metal production is measured in months instead of hours or at the most, days. Then too, after the ore body has been depleted and mining has ceased, metal production will continue for some substantial period of time. Heap leaching is also unique because unlike any other method of beneficiation, metal recovery cannot be accurately forecast ahead of time and recovery will never approach that of a conventionally milled sulfide ore or even that of a vat leached oxide ore. Counter-balancing this drawback, however, is the relatively low capital expenditure necessary to put a heap leaching operation into production and the consequence that smaller ore bodies which would not support the higher capital cost involved in a vat leaching plant can be made into producers. Stated more simply, in heap leaching the operator accepts low recovery in exchange for low capital costs and low break even point. Whether the operator chooses vat leaching with its higher recovery and higher capital costs, is a mater of economics which depends in part on the nature of the ore to decide. For instance, an ore that will vat leach in 7 to 10 days using 7 pounds of sulfuric acid per pound of copper produced might use double or triple that amount of acid during the months that are required for heap leaching.

Jan 12, 1968

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 W. M. Corse

AT THE TURN of the century the nonferrous alloy industry was awakening to the value of scientific metallurgy, and brass foundries and rolling mills began to establish their own research laboratories for scientific research and control. As the industry grew and its scope broadened it became apparent that an organization was needed that would stand in the same relation to the nonferrous industry as the American Foundrymen's Association did to the iron foundry business. The brass founders' group of the foundrymen's association discussed the matter and it was finally decided to appoint a com- mittee to draw up a constitution for a new organization to be known as the American Brass Founders' Association. Charles J. Caley was chairman and Dr. Richard Moldenke secretary of this committee. The object of the organization as defined by the constitution was the study of the technological development of alloying and founding non- ferrous metals, and furthering the advance of nonferrous metallurgy and the standardization of materials and operations in cooperation with the Bureau of Standards and engineering societies.

Jan 1, 1932

By Edwin Ludlow

EDWIN LUDLOW, president of the American Institute of Mining and Metallurgical Engineers for the year beginning Feb. 15, 1921, is a well-known figure in the state that was the birthplace of the Institute-Pennsylvania-although he was born and educated in New York and is again one of its residents, after years of active work in the field. Mr. Ludlow was born at Oakdale, Long Island, and was graduated from the School of Mines at Columbia University with the class of 1879. After graduation, he became a civilian worker with the U. S. Engineer Corps under General William Ludlow, his brother, and for two years did river and harbor surveying along the New Jersey coast.

Jan 1, 1921

By AIME AIME

THE Employment Bureau of the F. A: E. S., conducted under- the direct supervision of the secretaries of the four Founder Societies, has wanted to extend its activities and usefulness but it is operating right up to the limit of its budget; consequently, anything which requires the expenditure of more funds cannot be -undertaken, for the present. A great deal of time has been spent in recording, classifying, and interviewing the men listed, but owing to the business depression, only a comparatively small number of men have been placed' luring the last few months. There are men in New York from all over the country. What the Bureau needs is more positions available. With this in view, a number of high-grade engineers, themselves in need of employment, volunteered their services for a publicity campaign in the City of New York. A definite mode of procedure was evolved, and the success of the movement has been considerable, so much so that it has been thought well to call it to the attention, of members elsewhere, so that similar committees ' and campaigns might be organized in other cities. Following is a chronological arrangement of the methods used.

Jan 1, 1921

By AIME AIME

ASIDE from the annual dinner-dance, the two outstanding social events of the Annual Meeting were the dinner- smoker on Monday night and the informal dance on Tuesday night, both of which were held at the Commodore Hotel. Approximately 400 attended the former event, compared with 570 a year ago, and about 250, people were attracted to the dance.

Jan 1, 1933

By E. A. Holbrook

AS A whole, engineering schools have not awakened A to the fact that the workmen compensation laws passed in most of our states between 1914 and 1917 effected a quiet but none the less real revolution in. the relations between labor and management; no longer are industrial accidents unfortunate or careless happenings over which we feel a humanitarian interest and sorrow, they are a cost of the process and the finished product, as vital as improved design and increased efficiency. Last year the writer and others made a committee report to. the American Institute of Mining and Metallurgical Engineers on the cost of accidents in the coal industry of Pennsylvania. Comparatively the accident record in Pennsylvania coal industry is not high, yet the direct compensation cost plus the interference with operation cost of accidents was over 5 per cent. of the total cost of producing the coal. This stands out more vividly -if you realize that about 70 per cent. of the' cost of producing the coal is for payment of labor, wages that are fixed and over which engineering efficiency and management skill have little or no direct effect. This leaves 30 per cent. of the cost chargeable .to hoisting, haulage, overhead 'and other items subject to engineering control. One sixth of this is due to cost of accidents. Surely a direct place 'for an engineering attack.

Jan 1, 1925

By L. W. Bahney

FREQUENTLY in using a thermo-electric pyrometer for measuring the temperature of a furnace, a hole is drilled at the back or side of the furnace, through which is introduced the tube containing the thermo-couple. At times the couple is left almost where it drops, for the reason that it soon becomes too hot to be handled easily, and the space at the back or side of the furnace may be so small and uncomfortably hot that an easy and accurate adjustment is nearly impossible. In order to overcome this clumsy and unscientific method of using the thermo-electric pyrometer, I designed an adjustable stand, to hold the clay or quartz tube unclosing the platinum and plati-num-rhodium leads that constitute the couple of the Le Chatelier thermo-electric pyrometer. This stand also allows an easy and rapid adjustment of position to varying heights and angles, as may be desired for special reading. This stand is illustrated in Fig. 1. The couple in the tube might be of better service if the tube were held a little higher above the charge in a roasting-dish, changing the height and angle if desired. The stand, made of 1.5-in, water-pipe and mounted on casters, is heavy enough so it cannot be tipped over easily. It is adjusted to any position, and has a universal clamp which holds the clay or quartz protecting-tube. To avoid disturbing the wires of the couple at the cold junction each time the tube is moved, the cooling-bottle sets in a wire basket so placed that it moves forward or back with the couple. To overcome the necessity of leveling and adjusting a galvanometer at each furnace, a switch-board is used to connect

Jan 1, 1910

By W. Spencer Hutchinson

THE purpose of this account is to introduce to other engineers and geologists who use photography a means of interpreting topographic and geologic structure with the stereoscope. Anyone who finds this of sufficient interest to read it at all must cut out the pictures shown and have a good look at them through the stereoscope; there is no other way to appreciate what is meant. Most of us have been disappointed by the flatness of mountain pictures and by the lack of perspective in photographs taken to illustrate topographic and geo- logic features. The use of the stereoscopic principle was suggested by the work of the photographic division of the Air service during the war. Photographs of the battle line, taken from air planes, were mounted for stereoscopic study, with most remarkable development of topography, penetration of camouflage and, by the matching of pictures with a time interval between, sure revelation of new work by the enemy. Thus, two views taken from a plane flying at 10,000 ft., both of the same terrain but from different points, are mounted in proper relation and put into the stereoscope. If the distance between the two positions of the camera was 200 ft., the observer then sees the topographic and military features as though his eyes were 200ft. instead of 235 in. apart.. The result is startling in its revelation of features that are flat and unintelligible when viewed by the unaided eye or in a single photograph. The technic of the work, as developed during the war, was quite complex and

Jan 1, 1921

By AIME AIME

It is with the deepest personal sorrow, and with the regrets of the Steel Company of Canada, that I report to you the death of one of our most valued associates, the late Frank B. McKune, superintendent of the Open-Hearth Department of our company. Many of you will remember Mr. McKune for his long attendance at these meetings, for the intelligent interest he took ill them, as well as for his innovations in steel-production practices.

Jan 1, 1940

By R. H. SWEETSERS

A Discussion of Mr. Hall's paper, read at the Washington Meeting, February, 1905. R. H. SWEETSER, Sault Ste. Marie, Ont. (communication to the Secretary*) :-The recent work of furnace No. 1 of The Algoma Steel Co., at Sault Ste. Marie, Ontario, using for fuel, first all charcoal, then a mixture of charcoal and coke, and finally all coke, upsets the estimates given by Mr. Hall in the last two paragraphs of his interesting paper. Furnace No. 1 was built for a charcoal-furnace, and it was run on charcoal fuel from March 6 until July 9, 1905; then, for a week, a mix¬ture of charcoal and coke was used, and, since then, coke alone has been the only fuel. It is to be regretted that at no time, during the run on charcoal, was there enough charcoal on hand and " in sight'" to warrant blowing the furnace as hard as it should have been blown. During April and May the supply of charcoal limited the amount of blast to about 8,000 cu. ft. of air per min.; in June, to about 8,900 cubic feet. For a few days in July about 10,000 cu. ft. were blown, and then the maximum daily output, 173 tons (2,240 1b.), was reached. At all times the quality of the charcoal was poor, having been made from wood cut from three to four years before. Doubtless this furnace could have produced .200 tons of iron per day, even with this quality of charcoal, provided the supply had been sufficient; and with good charcoal I see no reason why it could not make as much iron per day as it has made with coke. During the one week of using a mixture of charcoal and coke, the changes in quantity of blast and composition of the slag followed each other so closely that no single condition could last long on the furnace. The results were good, and the pig-iron was about the same in quality as that made during the

Jan 1, 1906

Albert Arents, Alameda, Cal.: From Mr. Furman's description of his crucible-assays I infer that he regards iron nails as a necessary or advisable adjunct. Against such a notion I must beg leave to protest. Nails should not be used in

Jan 1, 1896

Extremes in temperature and weather, along with the highly corrosive nature of acid leach solutions used at open-pit copper mines, necessitates the use of pipeline systems that are both corrosion resistant and impervious to the environment.

Jan 6, 1976