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By John V. Beall

BROMO Seltzer blue has gone to war. The blue of the Bromo Seltzer bottle is a product of cobalt, the Nation's No. 1 strategic metal. When the National Production Authority, on Nov. 21, 1950, ordered a 70 pct cutback in domestic use of cobalt, a stab of pain was felt in the hearts of the glass, porcelain enamel, steel, paint, pottery, and electrical and electronic equipment industries. The reason: A full-scale wartime economy with astronomical requirements for jet engines, high velocity projectiles, armor plate, electronic equipment, and the many products needed to win a war. There is little potential comfort for cobalt users in nonessential manufacturing, and the military will be pinched for optimum supplies of the metal. However, if proper measures are taken immediately and current plans are completed, in two years there will be far more cobalt available than ever before. When normal times return, cobalt supplies should be sufficient to meet peacetime military requirements, and greatly expanded domestic requirements that will result from new technological development for wartime but adaptable to peacetime products. The pres-

Jan 1, 1951

By R. P. Smith

In 1937 the employees of the Hollinger Consolidated Gold Mines Ltd.. at Timmins. Ont., Canada, approached organized medicine for a plan to provide themselves and their families with a complete medical service including hospitalization. This approach was made because of two conditions: (1) the necessity for some organization whereby contributions could be made in instalments to offset the sudden and large expense connected with illness for which the average employee is not prepared, and (2) the need for a more cohesive quality of service to replace a contract practice then in vogue, which did not take care of the employee's family or dependents. In different parts of the United States and Canada similar plans were in force, not only for employed groups but for numbers of people in circumscribed areas. In Europe different countries had adopted various forms of health insurance plans. It then was no surprise that these employees as a group should ask for some similar plan. With the cooperation of the management, a plan was instituted. The plan has one object only—the provision of medical services, including the accessory services such as hospitaliza-tion, X-rays, nursing, and necessary drugs and medicines. It is not concerned with cash benefits, sickness and accident payments, or any form of monetary return as the result of illness, but is simply an organization to provide medical services and pay for them from a central fund. It is a nonprofit organization and the only shareholders are the employees and their families who contribute and who in turn receive services. The Hollinger plan is limited to the employees of the Hollinger mine, who live in Timmins and the immediate vicinity. At first, the membership was voluntary. In the third year, it was made a condition of employment, with the proviso that at the end of any Association financial year an employee may withdraw if he wishes to do so. After withdrawal, he cannot again become a member until the end of the next Association year, and then only by the payment of the back dues. This step was taken to ensure continuity, and to prevent employees from withdrawing when well and reentering when faced with impending illness or operations. The employee himself is subject to medical examination on application for employment, and if accepted is subject to further examination by a specialist in chest diseases under the Workmen's Compensation Board of Ontario. Thus it is possible to exclude those who have heart disease, tuberculosis, or other disabling conditions when first employed. Wives and families of employees are not subject to medical examination but other dependents of an employee—mother, father, or other relative—who are declared by the employee to be wholly dependent upon him must be examined. The employee

Jan 1, 1946

By W. M. Weigel

LESS advances in the technology of non-metallic minerals than for several years past mark 1931, and the cause is easily found. The universal depression and decreased markets for non-metallic as well as other mineral commodities has forced the producers to cut out all unnecessary expense and reduce operating costs to a minimum in order to keep going, even on a reduced output, and to prevent insolvency. The result. has been that but 'little research has been carried on, and such as has been completed has in but few cases been put into commercial practice on account of the expense involved in new equipment and plant changes. The trend in the industry has been more economic than technologic, and the greatest effort put on market studies and sales attempts to expand markets and scrutiny of present operating 'practice leading to reduction of cost of production. This tendency has been increased by highly competitive conditions and the buyer's market which has prevailed and to the fact that price has been a greater factor than quality in placing orders. Only in cases where improvements in technology would immediately and effectively reduce costs or where in special cases there was but little competition with almost a monopoly control has actual technical development taken place.

Jan 1, 1932

By Herty, C. H.

Iron oxide (FeO) plays an extremely important part in the manufacture of iron and steel. In the three major processes- blast-furnace, open-hearth, and Bessemer converter-iron oxide is the chemically predominant compound and controls to a large ex- tent the operation of the furnaces and the composition and quality of their respective products. In order to emphasize the importance of iron oxide in each process, they will be considered individually in some detail. THE OPEN-HEARTH FURNACE. Iron oxide is introduced into the open-hearth furnace in four ways : 1. The scrap charged into the open hearth is oxidized by the furnace gases, the amount of oxide formed depending primarily on the amount and type of scrap charged. It has been found' that with large scrap, 1.7 Ib. of FeO is formed per 100 Ib. of scrap charged, whereas with scrap of medium size about 5.3 Ib. of FeO is formed per 100 Ib. of scrap charged, when the period between the charging of the scrap and the addition of hot metal is 3 hours. 2. The decomposition of the limestone sets free CO, by the reaction

Jan 1, 1957

By H. L. TERWILLIGER

THOSE of us who have been following rock drilling work for the last 15 or 20 years can recall some of the problems that were encountered with the old piston type of rock drill and the solid steel which it used. There was frequent trouble in keeping a straight hole in badly broken ground when using the ordinary four- point bit that had a flare on the wings of about 14". The drill steel, when pounding down its hole, would follow the line of least resistance and draw away from the desired line when it encountered a weak side in the ground through which it was drilling. Some would overcome the difficulty by making long winged bits to prevent the steel crowding over; this would relieve the troubles to a great extent. There was trouble with the rifling of drill holes and inability to drill round holes in some ground. The cure for these ills was to use the "X" bit, rather than the crossbit. The "2" bits were brought out in an effort to make it easier to drill a round hole in bad ground. Most of these troubles were before the days when the mechanical drill sharpener was in as common use as it is today. It was not until the introduction of the Leyner type of rock drill, requiring hollow steel that the users of rock drills found themselves confronted with more difficult prob- lems than they had ever encountered before with drill steel because the steel had to stand more severe service.

Jan 1, 1924

By James E. York

AT a meeting of the American Society for Testing Materials at Atlantic City, June, 1908, Dr.. C. B. Dudley, in his presidential address,' showed the vital necessity of not only making a steel rail as good as in the past, but of making it considerably better in order to meet the present and prospective require¬ments of railroads. Doctor Dudley requested the co-operation of all who from personal experience could give information that would result in bringing about the production of a steel rail that could be relied upon to meet the present requirements. I have had considerable experience in the practical manufacture of steel of almost every grade, during the past 40 years, and I shall suggest changes that will bring about the results desired. Doctor Dudley has had a long experience as chemical and metallurgical expert for the Pennsylvania railroad, but he frankly admits that up to the present time both he and other metallurgical experts lack the practical knowledge of steel-making that is necessary to state correctly the reasons for the unreliability of the steel rails now produced. The necessity is self-evident for more positive practical knowledge on the part of these experts of what is possible and what is impossible regarding the practical manufacturing of steel rails from the ingot to the, finished product. Chemical knowledge in steel-making is far in advance of what it was years ago, and might be said to cover every requirement (in that department) for producing reliable steel. The study of the metallography of steel has been of great value, also the physical testing of steel, but this knowledge will only de-

May 1, 1909

By Otto Henry

THE purpose of this investigation was to determine the equilibrium diagram of the lithium-magnesium pair as a first step in studying the possible usefulness of these alloys as ultra-light structural materials. REVIEW OF THE LITERATURE The behavior of lithium towards magnesium was first investigated by Masing and Tammann.(I)? In order to prevent oxidation the alloys were made in iron tubes under an atmosphere of hydrogen; temperatures were measured with a glass-protected thermocouple. These investigators found that lithium and magnesium form two series of solid solutions separated by a miscibility gap between 85 and 95 per cent magnesium; that the alloys with 81 and 95 per cent magnesium showed a homogeneous structure under microscopic examination, while the alloy with 89 per cent magnesium contained two distinguishable crystallites; that the curve indicating the beginning of crystallization rises from the melting point of lithium to that of magnesium; and that no compounds of lithium and magnesium are formed. The equilibrium diagram was not plotted because no definite data were obtained for determining the solidus and the posi-tion of the miscibility gap in the solid state. The difficulties encountered in this investigation were: (1) that it was necessary to heat them as high as the melting point of magnesium in order to obtain homogeneous melts; at such temperatures the alloys attacked the glass protecting the thermo-couple; and (2) that at temperatures above 400° C. the lithium united

Jan 1, 1934

By RUSSELL C. FLEMING

THE important advances that have been made of recent years in mining and milling methods and in mechanical equipment at mines need no re- telling, but there has been a remarkable growth in one type of equipment which has gone nearly unnoticed. That is the increasing use of storage-battery locomotives underground. Since the war the number of these locomotives and their field of use have increased tremendously; their growing acceptance represents an al- most complete reversal of opinion from an earlier period when they were generally looked upon as in- adequate for the strain of mine service. At the time when storage-battery powered units were first making their bid for recognition, the use of power in haulage had already passed through several phases; hand tramming, rope haulage, compressed air locomotives, even gasoline locomotives, had all been used, ending finally in the general adoption of the electric trolley locomotive for practically all power-haulage requirements. It was, and is, conceded that the trolley loco- motive met more adequately the varied and severe conditions of mine service than any previous type of haul- age unit. Subsequent developments have had to endure comparison and surpass in performance that type of haulage before changes would be considered.

Jan 1, 1930

By David W. Brunton

FROM the old-fashioned " grab-sample " to the modern timing- . device, which takes a machine-sample with mathematical precision, there is a wide gap which was only crossed' by many years of toil and unremitting endeavor. Even to-day, notwithstanding the advancement in the art, "grab-sampling" is still practiced-sometimes to afford the unscrupulous mine-promoter a basis for fairy-tales with which to entrap the too-gullible investor, and often by milling and smelting companies to determine the amount of moisture in custom-ores. The latter practice is almost as reprehensible as the former, and it causes more trouble and ill-feeling between seller and buyer than all other factors put together. No reputable concern to-day would think of attempting to determine by grab-sampling the amount of gold, silver, lead, or copper contained in an ore, and yet many buyers expect the miner to accept the results of grab-sampling in the determination of the amount of water contained in the ore, forgetting that accurate results are just as necessary here as in the determination of the metals, because the result determines the percentage of weight of the ore which shall be excluded and considered to have no value whatever. Samples for the determination of moisture should be taken with as great care as samples for the determination of. metallic content, and in order to avoid the extra expense of a separate operation moisture-samples should be taken from the sample-safe. As the sample reaches the sample-bin in a smaller stream and by a more circuitous route than the "reject" travels in its path to the outgoing car, it loses more moisture en route, and a constant should be added to compensate for this difference. Carefully-conducted experiments have shown that the difference in loss of moisture between the two routes does not exceed 10 per cent. in summer and 7 per cent.. in winter. For instance,

Aug 1, 1909

By D. B. RUSHNORE, K. A. Pauly

Bulletin. No. 41, May, 1910. ABBREVIATIONS. Al. Ind., Alliance Industrielle. am. Elec'n.. . American. Electrician. Bull. As. Ing. El Bulletin de la Association des Ingenieurs Elec- triciens Sortis de l'Institut Electrotecnique Montefiore, Liege. Bull. Soc. bilge d' Elec Bulletin de la Société belge d'Electriciens. Col. Guard . Colliery Guardian. D. R. P Deutsches Reich Patent. Dilly. Poly Dingler's Polytechniches Journal. E. & DI. Jour Engineering and Mining Journal. E. T. Zeit Electrotechnische Zeitschrift. Eclair. Elec. L'Eclairage Electrique. 1;1. Anzeig Elektrotechnischer Anzeiger

Sep 1, 1910

By E. L. Oliver

IN OFFERING a few comments and suggestions on trends in mining practice, and the methods and tools of tomorrow's mining, perhaps it will be appropriate to start with the subject of education. Charles Kettering, one of the best-known scientists and experimentalists in the automotive industry once said, in effect, that tech- 111ca1 schools have to be carefid not to teach a lot of hard and fast rules that may have been true once, but aren't so any more, or won't be presently. Possibly the mining school of the future will concern itself less with what has happened and more with what is going to happen. It will be built about or around problems. Such a school will be judged, not by the number of its students but by the quality of its improvements. To such a school the industry will send for men to solve particular problems. The industry will doubtless at some time sup- port such a school financially though a lot of hard work will be required to organize miners to undertake such financing, primarily because the mining industry, other than that concerned with iron and steel, is too loosely knit. Each company tends to its own knitting too closely for its own good. Wouldn't it be splendid if the mining industry would finance a "problem school" as suggested by Mr. Kettering and others.

Jan 1, 1939

By C. L. Clark

EVERY user of steel should ask himself whether or not he is taking full advantage of the discoveries of the steel metallurgists during the last few years, or is merely buying grades that looked to be the best five or ten years ago for various specific purposes and have since proved perfectly satisfactory in his plant. If he has not kept abreast of the times, then it is probable that something better has been developed, or something just as good that costs less. Though this article will have to do with steel for high-temperature applications primarily, marked advances have been made in steels for other purposes as well.

Jan 1, 1940

[NOTE.-The names of authors of papers are printed in small capitals, and the titles of papers, in italics. Casual notices, giving but little information, are indicated by bracketed page numbers. Large Roman numerals are volume numbers; small Roman numerals after volume numbers following titles indicate the page on which the presentation of the paper is mentioned; Arabic figures refer to the text of the printed papers.] A Use Classification of Coal, (ASHLEY) LXII [xiv]; LXIII, 782; Discussion: (HALL), 794; (ZERN) , 795; (ASHLEY), 795 Absorbent material, liquid-oxygen explosives, LXXI, 1251. Absorbents for liquid-oxygen explosives, LXIX, 292, 299. Absorption : cupellation : gold, special cupels, LIX, 194. primary and secondary, LIX, 213. ratio of silver to gold, LIX, 212. silver, specla1 cupels, LIX, 195. Absorption method, gasoline from natural gas, LIX, 584, 585. Absorptzon of Sulfur from Producer Gas zn Open-hearth Furnaces (NEAD), LXX, 176; Discussion: ( WATERHOUSE), 184 ; (REYNDERS) , 184; (KINNEY), 184 Accelerated wearing tests, bearing metals, LXIX, 973. Accident prevention, results, Utah, LXVIII, 360 Accident Prevention, 1919 (SINN), LXIII, [xiii] Accidents: causes in coal mines, LXXI, 1229. classification, Anaconda Copper Mining Co., LXVIII, 9. coal mining: comparison with metal mining, LXVIII, 360. pillar mining, LXVIII, 323. relation to method, LXVIII, 323 shafts, LXVIII, 207, 209 Utah, LXVIII, 363 - concentrating mills, Utah, LXVIII, 362 liquid-oxygen explosives, LXIX, 330, 339 losses through, LVIII, 65 metal mining, LXVIII, 361, 363. mine: causes, LIX, 652. curve of decrease, LIX, 655 days of greatest frequency, LIX, 657 human element as cause, LIX, 652, 653. intemperance as cause, LIX, 658 labor relation, LIX, 652 prevention, LIX, 653. record, New Jersey Zinc Co., Franklin mine, LIX, 655 time of greatest frequency, LIX, 657, 658 Utah, LXVIII, 360 prevention, LVIII, 65 report blanks, Anaconda Copper Mining Co, LXVIII, 13, 15. statistical base, Anaconda Copper Mining Co, LXVIII, 9 time lost, LVIII, 70 transportation, Clifton-Morenci district, LXX, 851.

Jan 1, 1926

By R. J. Arsenault

The yield drop that occurs in tantalum, Cu-AZ. and Ag-Al was investigated as a function of strain rate and at several temperatures. From the strain-rate dependence of the yield drop an activation volume was calculated and found to agree with that obtained from differential strain-mte tests. The temperature dependence of the yield drop can he explained in terms of the parameter temperature divided by activation volume. The yield drop is attributed to the rapid multiplication of dislocations during their motion. THE yield-point or yield-drop (upper yield stress minus the lower yield stress) phenomenon has been the subject of numerous investigations1-9 in both bcc and fcc metals. Also, there is no dearth of theoretical explanations10-20 to account for the yield-point phenomenon. The present explanations can be divided into two categories: the concept of dislocation locking and subsequent unlocking and the concept of multiplication of dislocations due to their motion. The Vottrell10,11mechanism of locking and unlocking, as applied to bcc metals, is the best known of the three proposed locking mechanisms. The two additional mechanisms, short-range order (SRO)7,16,17 and Suzuki-type locking,14,15 have been employed to account for the existence of yield points in fcc metals. The experimental evidence supporting the locking of dislocations, especially in bcc metals, is well-established. The dependence of the yield point on interstitial concentrations,' the kinetics of strain aging,2 and the observations by electron-transmission microscopy18 are some of these experimental results. The number of experimental observations supporting dislocation locking in fcc metals is not as extensive as in bcc metals. The unlocking of dislocations, which actually is supposed to account for the yield drop, is by no means well-established by experimental results for either bcc or fcc metals. The similar temperature dependence6 of the yielding and plastic flow is one of the experimental factors that cannot be explained in terms of the unlocking of dislocations. The mechanism based on the rapid multiplication of dislocations has been proposed by several investigators. 18-20 Johnston and Gilman19 have proposed a detailed model of yielding, which was later employed by Hahn21 to predict quantitatively the yield drop in iron. This mechanism was discussed in a previous paper22 and several limitations were pointed out. In the same paper it was shown that an activation volume could be obtained from the strain-rate dependence of the yield drop and that a correlation existed between the activation volumes obtained from the yield-drop tests and from differen-

Jan 1, 1964

By DOOLITTLE E. M.

(Canal Zone Meeting, November, 1910.) The following notes are contributed, not with the idea of offering a complete history of the development of this very important process as applied to the Leadville district, but with the hope that the practice, as it was carried out in the Bi-Metallic Smelter, may still be of interest to others. The Bi-Metallic Smelter, at Leadville, Colo., was the first to make a commercial success of the process described in the following pages, which consisted essentially of smelting raw silver- and copper-bearing sulphide ores in blast-furnaces to form a matte, which was generally re-smelted with siliceous ores for a second high-grade matte. Robert Sticht, in his excellent monograph on the subject,1 has outlined briefly the plant belonging to this company. He says, in effect: The Boulder, Mont., enterprise set the example for others with whom the patentee (w. L. Austin) had been negotiating, and the old La Plata lead-smelter at Leadville, Colo., was fashioned into a crude, temporary experimental plant for the Bi-Metallic Company, and the feasibility of the process demonstrated by a trial run. Subsequently, the plant was considerably improved, and, being supplied with very favorable ores, continued to run without interruption from August, 1892, to June, 1893. In September, 1893, smelting was resumed in a completely remodeled establishment, some $200,000 having been expended upon the new work. Thus, aside from the Montana experiments, which, under the direction of W. L. Austin, began as early as- 1885 2 at Toston, and continued with indifferent success for six or seven years, the Bi-Metallic plant at Leadville may be said to have * Formerly Superintendent, Bi-Metallic Smelting Co. + Formerly Chief Assayer and Chemist, Bi-Metallic Smelting Co. 1 Modern Copper Smelting, E. D. Peters, 7th ed., p. 415 (1895). 2 Trans., xvi., p. 259 (1887-88).

Dec 1, 1910

Joseph W. RichaRds, South Bethlehem, Pa. (communication to the Secretary*): The hold experiment of Mr. James Gayley in drying the blast used in the Isabella furnace has attracted the attention of the whole metallurgical world, and has given rise to a wide discussion of the reasons for its great success. Mr. Gayley and the capitalists who backed him in his work deserve congratulations on the success of the venture, not only because it succeeded, but because they have been rewarded far beyond the maximum that could be expected from theory or probability. To state the case in its simplest terms, all that could have been predicted was: (1) that the removal of the moisture from the blaet would result in the saving of the heat required for its decomposition, representing from 3 to 5 per cent. of the heat-value of the coke used; hence about that quantity of fuel might be saved; (2) that the furnace would be somewhat more independent of variations in the weather; (3) that the campaign would be a little hotter; and (4) that the speed of the blowing-eugines would be decreased, at least in amount proportionate to the reduction in temperature of the air led to them. I do not think anyone anticipated a much larger output per day. The results actually attained were: (1) the furnace made an increase of 24.86 per cent. in the output of pig-iron per day; (2) it consumed 19.6 per cent. less coke per ton of pig-iron made; (3) the blowing-engines were run 15.8 per cent. slower; and (4) the saving in power made up for the power required to run the refrigerating-plant. In addition, the blast was hotter; the waste-gases cooler, because of their smaller volume; and there was a greater proportion of carbon dioxide to carbon

Jan 1, 1906

Officials of the State Department have expressed their hope that a considerable number of technical men will take the examination for consular service. The Department recognizes that the interest of the United States will be served best if technical men are made available through these examinations for vacancies at points where their training will be of special value. Industrial engineers who have passed the con-sular examination will be assigned to industrial centers of Europe or South America. Mining engineers, chemists, electrical engineers, etc., will be assigned to industrial centers requiring special training.

Jan 11, 1919

By A. J. de Witte

INTRODUCTION The importance of determining dips of subsurface formations in wells, especially in wildcat wells, is self-evident and need not be enlarged upon. Various dipmeter instruments have been described in technical literature1,2,3,4 over the years. The introduction of the continuous dip-meters3,4 has made the earlier types obsolete. Continuous dipmeter logs are run by at least two different major service companies. Included as part of the service are a limited number of dip calculations—usually 10—made at different levels from the log. Very frequently this is the total result of a dip survey. It is believed that dipmeter surveys would be of considerably more advantage if geologists and engineers were able to make their own calculations from the original records. Determination of dips from the dipmeter record starts with the correlation of three log curves taken at different sides of the borehole. It cannot be over-emphasized that the quality of the results hinges primarily on this correlation. Nobody should be better qualified to correlate logs than a subsurface geologist or field engineer. The next requirement is to have an easy yet accurate way of computing the dip from the correlated points. Service companies use a mechanical device for this purpose. Directions for a graphical method were given in a recent article by B. 0. Prescotts. This paper describes a different graphical technique which, in our experience, is simpler, faster and at least as accurate. The entire manipulation is carried out on the stereonet in a number of easy moves. The paper is divided into two parts. This first part contains the introductory sections and full explanation of the geometry involved. The second part reviews the reading of data from an actual field log and summarizes the practical rules for computation of dips, the whole process being illustrated by an example. Following the outlined procedure, one could calculate a good many levels in a relatively short time, thus being able in particular to check suspected anomalies such as fault zones or unconformities in as close detail as the log will permit. GENERAL EXPOSITION OF THE METHOD Prnciple of the Dipmeter The position of a plane in space is defined by the location of three points, not on a straight line. Referring to Fig. I, if a borehole traverses a bedding plane, we can determine the strike and dip of the bed by finding three points which are not in line along this plane. Such points as A, B, and C are obtained with the dipmeter. The device consists of three electrodes (or caliper arms)1, 2, and 3 spaced at 120 angles, as schematically indicated, whose readings are separately recorded (Curves 1, 11, 111, to the right). When electrode 1 passes the boundary of the bed, Curve I will kick, etc. From these curves, we know the relative distances of points A, B, C, measured along the axis of the hole. If A is at zero, then B and C are at levels d1 and d2 up the hole,

Jan 1, 1957

By J. S. Marsh

TUESDAY, Feb. 16, was no day for strolling along the cold sidewalks of New York, and a large number of metallurgists sat down with pleasure to the warming task of wiping a few soldered joints. Presented by a joint-wiper of the modern school, G. M. Bouton, of the well-known team of Schumacher, Bouton, and Phipps, the initial paper brought into focus the theme of conservation of strategic metals and described the technique of making the fillet-type joint now employed by the Bell System. Using an over-all average of only 40 per cent of the solder formerly used by the conventional method. this important development bids fair to stick when the war is over. D. L. Martin and E. R. Parker then described the embrittling effect of hydrogen on silver previously heated in oxygen and the less serious but troublesome result obtained under the converse conditions. An interesting example of grain growth restriction created additional material for the lively discussion that ensued among those who have encountered one or another of these phenomena in silver and copper.

Jan 1, 1943

By Joseph N. Morrison

A comprehensive solution is offered to the problem of dust emissions at belt conveyor transfer points. Details of enclosure design are discussed and a straightforward procedure for calculating required dust control exhaust volume is presented. Many design variables are taken into account which heretofore have been commonly ignored or inadequately considered. These include belt widths, belt speeds. enclosure openings, material flow rate, material bulk densities, material lump sizes, height of material fall, material temperature, and ambient air temperature. All of these questions are handled by means of a "fill-in-the-blanks" type of calculation form, permitting quick, reliable solutions by relative "non-experts."

Jan 1, 1972