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By R. W. Raymond

THIS meeting was held in the new home of the Institute, the United Engineering Society Building, 29 West 39th Street, New York City, directly following the Dedication ceremonies. The first session was held in the large Auditorium, Thursday, April 18. The meeting was called to order by Mr. John Hays Hammond, President of the Council, who said Before taking up the reading and discussion of papers, I will call upon Dr. Rossiter W. Raymond, the oldest living past-President of the Institute, who has been in harness almost continuously for thirty-six years, and who has contributed more than any one else to bring this society to its present great success and to establish the reputation of the American mining engineer the world over, for a few words supplementary to those which were uttered to engineers generally, during the sessions of yesterday and the day before. ADDRESS BY R. W. RAYMOND. The generally accepted Darwinian doctrine of the survival of the fittest is sometimes illustrated by persons who are supposed to be the fittest because they have simply survived. I fear that I come under that category. Almost all of my contemporaries in the early history of this Institute have passed away. Only one or two of the original founders remain, and I may fairly say that scarcely any remain who were active at that : time in shaping the organization and the future career of the Institute. In May, 1871, I was thirty-one years old. Next week I shall be sixty-seven years old. All the intervening years have been devoted to the service of this Institute almost continuously, either as President or Vice-President or Secretary. You may easily imagine, therefore, with what pleasure I greet you on this occasion. I am not here to extend to you the welcome of the City - of

May 1, 1907

By Richard H. Olson

"Rarely in our technological society does the discovery of a new class of inorganic materials result in such a wide scientific interest and kaleidoscopic development of applications as has happened with the zeolite molecular sieves." The foregoing, the opening sentence in a landmark volume on zeolite molecular sieves by D. W. Breck (1974), is, if anything, an understatement. Zeolites were recognized as a new group of minerals in the 1750s, but it was not until 1930 that the first analysis of the crystal structure of a zeolite mineral was made. In the late 1940s research workers at Union Carbide Corp. began a program of zeolite synthesis and study which has resulted in one of the major research achievements of all time. Naturally, with the vast research and development efforts devoted to the synthetic molecular sieves, Union Carbide became concerned in the mid-1950s about its position should minable deposits of natural analogues be discovered. Zeolite minerals have diverse origins, and even a brief discussion of these is beyond the scope of this paper. The early work on zeolites was confined to igneous rock occurrences (e.g., amygdules and veins) which were formed by "space-filling;" these crystals tend to be euhedral, thereby rendering them appealing to both mineralogists and collectors. During the first year or so of Union Carbide's exploration (which began in mid-1957) attention was devoted solely to such igneous occurrences. A landmark paper by Bramlette and Posnjak (1933) heralded the potential significance of the occurrence of zeolite minerals as alteration products of vitric ash and similar materials. In the summer of 1958, full attention was directed by Union Carbide to the search for deposits of this type in the western United States. Since then, such exploration has been continu-

Jan 1, 1975

By C. T. Holland

This discussion is concerned with those com-J- paratively infrequent bumps that eject material from the failed mass with enough energy to wreck heavy machinery and seriously injure or kill people. In such cases there is a loud report, and the pressure waves set up in the mine atmosphere wreck ventilation controls several hundred feet from the site of the failure. Vibrations are induced in the earth's crust which may be detected several miles from the point of origin, and explosive gases may be released in large quantities." Usually a dense suspension of dust is produced from the failed mass, together with dust placed in suspension by the resulting air blast. These rock bursts or bumps have also been called mountain shots, bounces, pillar bursts, and crumps. Such occurrences, when extensive, are serious catastrophes, and may force abandonment of the mine.' CAUSES OF ROCK BURSTS Rock bursts in coal mines have occurred in sev-eral places under diverse geological conditions, mining methods, and/or practices. A study of many such occurrences indicates that they depend on the following conditions: 1) cover thickness of 500 ft or more, 2) cover composed of strong members and having a strong member lying close to or on the coal bed, and 3) a floor that does not readily heave. The minimum thickness of cover under which coal mine rock bursts occur is based on observation. Under unusual circumstances involving very strong roof members and/or mining systems, and/or practices especially likely to induce bursts, a burst conceivably could occur under less roof. Under special circumstances rock bursts have occurred in marble quarries almost at the surface.' Furthermore, under very heavy cover it is likely that controlling roof members need not be as strong and as close to the coal bed to cause bumps. Just what constitutes a strong roof or roof member is open to question. Obviously the strength of a roof member is determined by its thickness, the distance between bedding planes across which little or no bond exists, the spacing and development of joints, and the inherent strength of the rock material. Strata sections showing roofs under which rock bursts in coal mines have developed are illustrated in Fig. 2. In several instances the strength of rocks composing the roof of mines developing bumps has been tested. The tests (Table I) show that these rocks develop considerable strength in compression, bending, and shear and that in some cases the strengths are very high. No quantitative data are available concerning joints in roof members over coal beds where rock bursts have occurred, but the author has examined many mines subject to bursts and has received the impression that joints in the shales immediately over the coal beds are always present and well developed. In the main sandstone or conglomerate members themselves, however, where observed, he has yet to see a fracture system indicating well developed joints. Undoubtedly joints are present, but the evidence indicates that they are few, poorly developed, and widely spaced. In a mine subject to bumps, moreover, actual measurements of roof spans up to 225 ft between supports under a cover of about 800 ft have been made before roof failure occurred. Such spans signify strong roof. In coal beds subject to rock bursts, the bottom rock is usually a sandy shale. A few tests (Table I) have been made on the floor rock of coal beds. Observations in mines indicate that they are usually weaker than roof rocks and that under load they show more plastic effects. Observation in ground subject to bursts invariably indicates a relatively strong floor highly resistant to heaving, although some heaving may occur. Other factors listed as favorable to rock bursts are: 1) mountainous surface; 2) steeply dipping beds; 3) proximity of faults, folds, and other similar geologic structures. Many bursts have occurred in mines under mountainous country, although many bursts in mines under a surface with little relief indicate that thickness of cover, not relief, is the essential factor. In steeply dipping beds, many bursts occur in mines that are essentially flat, and rock bursts have been recorded in beds dipping as much as 35o Most rock bursts in the U. S. occur in beds that dip less than 10 pct. It is also true that most U. S. coal is produced from beds dipping less than 10 pct. Geologically, faults are regarded as providing stress relief, but in the vicinity of faults, as well as sharp folds, it would seem that residual stresses could be present. The fact that rock bursts occur in areas remote from faults and sharp folds suggests that their presence is not necessary for this phenomenon to take place. There have been many bursts close to faults and folds, and it may be assumed that occasionally such structures accentuate their occurrence3 The conditions and circumstances under which they occur, coupled with the effects produced, leave In the Crowsnest Pass coalfield, British Columbia, a rock burst is estimated to have released 1.8 million cu ft of methane.

Jan 1, 1959

By AIME AIME

THE following paragraphs comprise such information as the Secretary has been able to obtain concerning the members and associates whose deaths have been reported. Further particulars or corrections of errors, and biographical data concerning deceased members or associates not already noticed in this way, are solicited. Pat Doyle was born in 1849. At the age of fifteen he entered the Civil Engineering College of Madras, India, and left it at seventeen, having achieved special distinction in mathematics, chemistry,. and geology. Before be was eighteen years old he was in charge of two of the most important Sub-Divisions in the Madras Presidency, where he had ample opportunities for acquiring a preliminary knowledge of his profession, which was his chief object in joining the Public Works Department. In 1867, his energetic measures saved the island of Seringham from disastrous inundation. At this period he began contributing to the press ; and after a varied practical experience he came into public notice again in 1876, with an article in the Colliery Guardian on Indian Mines and Mining. In 1877 he became a Fellow of the Statistical Society of London. He was a founder of the Straits Branch of the Royal Asiatic Society and a life member of the parent Society of Great- Britain and- Ireland, as well as a member of the Independent Asiatic Society of Bengal. In 1878-9 he was Chief Superintendent of the Public Works of Perak; was active in having the Associate Member Class added to the Institution of Civil Engineers; and became a member of the Society of Engineers of London and of the North of England Institute of Mining and Mechanical Engineers. In 1880 he went to the Southern Colonies and held several appointments in Australia, where he became a member of the Johnsonian Club, Brisbane, and the Queensland Philo-

Jan 5, 1908

By AIME AIME

WIDESPREAD interest in the better utilization of coal is indicated by the attendance of over seventeen hundred men interested in the pro- cessing and utilization of coal and its by-products, at Pittsburgh, Nov. 15 to 18. The conference was truly international in scope and of a scientific character, and must be considered a real success. There were dele- gates--official and unofficial-from America, Belgium, Canada, Czechoslovakia, France, Germany, Great Britain, Japan, Mexico, and Sweden. Several Federal and 28 State departments had representatives, also many colleges and universities, and many leading industrial and mining corporations throughout the country. A feature of the sessions was that papers were mostly read in full and attentively listened to, although in some cases they were of a technical nature. The proceedings were opened by the president of Carnegie Institute of Technology, Thomas C. Baker, who spoke of the importance of the conference and felt that without foreign cooperation it could not have been held. There was no need to apologize for the movement of Carnegie Institute of Technology in the matter. Coal is commanding attention in every part of the world; so is power; and coal will remain the chief source of power for generations to come. The coal chemist is working with the engineer, and nobody can forecast what developments there will be in fuel technology. This conference may be the turning point of fuel technology in America. The development and application of these new processes may be of great benefit to Pittsburgh.

Jan 1, 1926

By David B. Reger

New discoveries of gas in the southern counties featured the petroleum industry in West Virginia during 194;. Drilling for oil increased slightly over 1944 and a small increase of initial production resulted. Out of 28 wildcats drilled, there were 16 gas discoveries and 12 dry holes. No commercial oil was found in the 28 wells.

Jan 1, 1946

By Bever M. B., Floe Carl F., Hung Liang

Data on the solubility of hydrogen in iron-silicon alloys are of practical interest, as hydrogen causes gas unsoundness and embrittlement in iron and steel and is also a factor in the metallurgy of cast iron. Zapffe and Simsl have recently demonstrated that in deoxidized iron and steel castings gassiness and bleeding are primarily functions of the hydrogen content of the liquid metal. These authors also suggested convincingly that ordinary melting and casting practice provides several sources of hydrogen for absorption by the metal. Norbury and Morgan2 and Boyles3 have shown that dissolved hydrogen affects the graphitization of cast iron. Schneble and Chipman4 included in a study of the effects of superheating on the properties of cast iron an investigation of the part played by hydrogen. Schwartz, Guiler and Barnett5 investigated the significance of hydrogen in the metallurgy of malleable cast iron. A complete interpretation of investigations of this kind calls for equilibrium values of the solubility of hydrogen in the liquid and solid phases. From the theoretical standpoint, the solubility of gases, especially hydrogen, may reveal some aspects of the nature of liquid metallic solutions. This was implied in the early work of Sieverts6 on the effect of alloying additions on the solubility of hydrogen in copper. Recent work by Bever and Floe7 has shown that in liquid copper-tin alloys the solubility of hydrogen changes abruptly at the composition of the intermetallic compound Cu3Sn. It is of considerable interest to determine whether liquid alloys of iron also have compositions at which the solubility of hydrogen exhibits a discontinuous or otherwise unique behavior. Among the various alloys of iron the iron-silicon system is important because of the presence of silicon in various structural alloy steels, transformer sheets, cast irons and special acid-resisting castings. The various grades of ferrosilicon, finally, cover almost the entire remainder of the composition range. Published information on the solubility of hydrogen in iron-silicon alloys is meager. The first values for pure liquid iron were reported in 1910-191 1 sieverts and Krumbhaar8 and by sieverts.9 They found that 100 grams of iron absorbs 28 c.c. of hydrogen at 1550°C and One atmosphere pressure, and 31 C.C. at 1650°C. In 1938 Sieverts, Zapf and Moritz10 published a value of 26.3 C.C. at 1550°C. Data on the solubility of hydrogen in liquid iron-silicon alloys and in liquid silicon are not available. Martin1' investigated

Jan 1, 1947

By Bever M. B., Floe Carl F., Hung Liang

Data on the solubility of hydrogen in iron-silicon alloys are of practical interest, as hydrogen causes gas unsoundness and embrittlement in iron and steel and is also a factor in the metallurgy of cast iron. Zapffe and Simsl have recently demonstrated that in deoxidized iron and steel castings gassiness and bleeding are primarily functions of the hydrogen content of the liquid metal. These authors also suggested convincingly that ordinary melting and casting practice provides several sources of hydrogen for absorption by the metal. Norbury and Morgan2 and Boyles3 have shown that dissolved hydrogen affects the graphitization of cast iron. Schneble and Chipman4 included in a study of the effects of superheating on the properties of cast iron an investigation of the part played by hydrogen. Schwartz, Guiler and Barnett5 investigated the significance of hydrogen in the metallurgy of malleable cast iron. A complete interpretation of investigations of this kind calls for equilibrium values of the solubility of hydrogen in the liquid and solid phases. From the theoretical standpoint, the solubility of gases, especially hydrogen, may reveal some aspects of the nature of liquid metallic solutions. This was implied in the early work of Sieverts6 on the effect of alloying additions on the solubility of hydrogen in copper. Recent work by Bever and Floe7 has shown that in liquid copper-tin alloys the solubility of hydrogen changes abruptly at the composition of the intermetallic compound Cu3Sn. It is of considerable interest to determine whether liquid alloys of iron also have compositions at which the solubility of hydrogen exhibits a discontinuous or otherwise unique behavior. Among the various alloys of iron the iron-silicon system is important because of the presence of silicon in various structural alloy steels, transformer sheets, cast irons and special acid-resisting castings. The various grades of ferrosilicon, finally, cover almost the entire remainder of the composition range. Published information on the solubility of hydrogen in iron-silicon alloys is meager. The first values for pure liquid iron were reported in 1910-191 1 sieverts and Krumbhaar8 and by sieverts.9 They found that 100 grams of iron absorbs 28 c.c. of hydrogen at 1550°C and One atmosphere pressure, and 31 C.C. at 1650°C. In 1938 Sieverts, Zapf and Moritz10 published a value of 26.3 C.C. at 1550°C. Data on the solubility of hydrogen in liquid iron-silicon alloys and in liquid silicon are not available. Martin1' investigated

Jan 1, 1947

By Carl F. Floe, Hung Liang, Michael B. Bever

DATA on the solubility of hydrogen in iron-silicon alloys are of practical interest, as hydrogen causes gas unsoundness and embrittlement in iron and steel and is also a factor in the metallurgy of cast iron. Zapffe and Sims1 have recently demonstrated that in deoxidized iron and steel castings gassiness and bleeding are primarily functions of the hydrogen content of the liquid metal. These authors also suggested convincingly that ordinary melting and casting practice provides several sources of hydrogen for absorption by the metal. Norbury and Morgan,2 and Boyles3 have shown that dissolved hydrogen affects the graphitization of cast iron. Schneble and Chipman4 included in a study of the effects of superheating on the properties of cast iron an investigation of the part played by hydrogen. Schwartz, Guiler and Barnett6 investigated the significance of hydrogen in the metallurgy of malleable cast iron. A complete interpretation of investigations of this kind calls for equilibrium values of the solubility of hydrogen in the liquid and solid phases. From the theoretical standpoint, the solubility of gases, especially hydrogen, may reveal some aspects of the nature of liquid metallic solutions. This was implied in the early work of Sieverts6 on the effect of alloying additions on the solubility of hydrogen in copper. Recent work by Bever and Floe7 has shown that in liquid copper-tin alloys the solubility of hydrogen changes abruptly at the composition of the intermetallic compound Cu3Sn. It is of considerable interest to determine whether liquid alloys of iron also have compositions at which the solubility of hydrogen exhibits a discontinuous or otherwise unique behavior. Among the various alloys of iron the iron-silicon system is important because of the presence of silicon in various structural alloy steels, transformer sheets, cast irons and special acid-resisting castings. The various grades of ferrosilicon, finally, cover almost the entire remainder of the composition range. Published information on the solubility of hydrogen in iron-silicon alloys is meager. The first values for pure liquid - iron were reported in 1910-1911 by Sieverts and Krumbhaar8 and by Sieverts.9 They found that 100 grams of iron absorbs 28 C.C. of hydrogen at 1550°C. and one atmosphere pressure, and 31 C.C. at 1650°C. In 1938 Sieverts, Zapf and Moritz10 published a value of 26.3 c.c. at 1550°C. Data on the solubility of hydrogen in liquid iron-silicon alloys and in liquid silicon

Jan 1, 1946

By Betty J. Laswell, Gerald W. Laswell

The stepped-up pace of US open-pit and surface mining during the 1970's is a direct response by mining firms and equipment manufacturers to rising costs and declining ore grades. In the race for bigger and more efficient machines, rotary drills have emerged as the foremost leader in primary drilling at major US surface operations. At least 12 different manufacturers now offer rotary rigs in the 102- mm-diam. (4-in.) or greater blasthole size range. With capital investment for the larger units quickly approaching $1 million, the question is asked, "What's been the performance record to date of rotary drill rigs operating in North America?" To answer that question, a comprehensive study of rotary blasthole drills was conducted which qualitatively reveals various problem areas inherent in the rotary drill market and indicates some new directions for improvement.

Jan 6, 1978

By L. D. Godshall

The latest revised edition of Mr. C. A. stetefeldt's book on the Lixiviation of Silver-Ores, which appeared very recently, contains no mention of the volatilization of silver in chloridizing-roasting—an omission which is the more remarkable in view of the fact that in former editions of the work this important subject was noticed. Moreover, Mr. Stetefeldt has discussed it to some extent in his paper on " The Stetefeldt Furnace," * in which he criticised certain statements made by me before the Colorado Scientific Society in May, 1893, in a paper entitled " A Review of the Russell Process;" ? and Mr. Morse, in his paper on " The Lixiviation of Silver-Ores by the Russell Process at Aspen, Colorado," $ has given statistics showing the loss of silver by volatilization (including the dustloss, which Mr. Morse estimates at not more than 1 per cent.) on more than 30,000 tons of ore roasted, to have been 9.16 per cent. The matter must certainly be deemed important enough to warrant me in returning to it, and offering, with the aid of the figures made public since my first paper, a reply to the criticisms of Mr. Stetefeldt. The passages of my paper which he deemed to be " ques-

Jan 1, 1897

The economics of aerial survey and the technical processes by the aid of which vertical and oblique aerial photographs are turned into line maps showing the most profuse topographical detail such as contours, rivers, roads, plantations, habitations and cultivated lands do not concern us here. They have been ably and exhaustively described in the publications of the British War Office, handbooks on surveying methods and on photogrammetry and in the South African mining, engineering and geological press. Suffice it to mention that for geological interpretation vertical photographs are used on such scales as 1/5000 to 1/10,000, overlapping each other by 55 to 60 per cent in the direction of flight and some 10 to 20 per cent sideways on to the next sequence or strip. Through this duplication in the overlap the stereoscopic examination becomes possible. The standards by which monochrome aerial photographs are interpreted can be grouped under the following headings: 1. Continuity.—The continuity of topographic relief not obtainable on the ground owing to the smallness of man relative to that relief. Here lies the greatest value of aerial survey with relation to geology. An immediate alignment can often be made of drainages running in different directions on each side of a hill; saddles and gorges in the mountainsides; abrupt termination of outcrop or indubitable signs of faulting. Most conclusive evidence is thus often obtained about faults which may be perfectly visible at one place on the ground but cannot elsewhere be identified because of decreased throw. Similarly, dikes can often be followed notwithstanding frequent interruption and disappearance under the soil. Scattered outcrop in scrub-covered or bush-covered country can be conveniently located and often correlated, with a large saving of time compared with field work. The same applies to geological contacts. Once these have been established at a few points on the ground, the intervening stretches can be drawn in.

Jan 1, 1937

By T. Watanabe, S. Karashima, H. Oikawa

Creep tests of a! iron and its solid-solution Fe-Mo, Fe-Co, and Fe-Si alloys with bcc structure were conducted under constant stresses in ferromagnetic and paramagnetic temperature regions above 0.5T,(T, is the absolute melting temperature). It was found their high-temperature creep behavior changed in the vicinity of the magnetic transformation temperature, that is Curie temperature, TC. In the ferromagnetic region below the steady-state creep rates were lower than those expected from the extrapolation of the data in the paramagnetic region, the amount of decrease being affected by solute addition. Also, activation energies for steady-state creep were different in the two temperature regions. The observed changes were concluded to be due to the effect of ferromagnetism on diffusion. It is well-known that plastic deformation of metals and alloys in the temperature region where mobility of atoms becomes high enough is controlled by atomic diffusion." Many experimental results394 on fcc and hcp materials have been reported to confirm this view. In bcc metals and alloys, not much basic investigation of creep deformation has been performed. In particular, experimental work on iron5-&apos; and its alloys, covering a quite wide temperature range is extremely scarce. On the other hand, the effect of ferromagnetism on diffusion has recently been demonstrated in a iron and its alloys;&apos; it has been made clear that diffusion rates in ferromagnetic temperatur~e region are significantly lower than those expected from diffusion measurement in the paramagnetic region. Therefore, it is concluded that the magnetic effect influences the high-temperature creep behavior in a! iron and in its alloys. The present authors have conducted creep experiments on a iron and its solid-solution alloys over a very wide temperature range, and have demonstrated the magnetic effect. A part of the result has already been reported elsewhere.26 In this paper, the experimental results will be described in detail. While the manuscript was in preparation, a similar magnetic effect on creep deformation of a iron was reported by Ishida . Though their experiments covered an extremely wide temperature range, the creep stresses varied from several thousand psi to several ten thousand psi with decreasing temperature. Consequently, it may be said that there remain some questions concerning their results. I) EXPERIMENTAL PROCEDURE The materials used in the experiments were pure iron and its alloys; they were prepared by vacuum melting (10"" mm Hg) electrolytic iron (99.9 pct), molybdenum powder (99.9 pct), ultrapure silicon, and cobalt pellet (99.5 pct) in alumina crucibles. The ingots were hot-forged to plates 10 mm thick and 50 mm wide, and then were hot-rolled at about 700°C into sheets 1 mm thick. Creep specimens, 5 mm in width and 15 mm in gage length, were machined from the sheets. They were annealed at temperatures which were well above their respective recrystallization temperatures. The chemical compositions of the metal and alloys are shown in Table I together with their heat treatments. High-temperature creep tests by the use of a lever-type creep testing machine were carried out in argon atmosphere under constant tensile stress. In order to keep &eep stress constant within about *0.5 pct, stress change due to specimen elongation was compensated by tensile force of a stainless-steel bellows which was inserted between the loading lever and lower specimen grip with the assumptions of a linear relationship between change in cross section and strain and uniform strain along the section. Beyond the limit of compensation by the bellows, small amounts of load were removed after appropriate strains. The testing temperatures were maintained to within i2"C of the reported values. Creep deformation was auto-graphically recorded at the upper (moving) specimen grip using a linear differential transformer which was held by a stainless-steel rod mechanically connected to the lower specimen grip. It was also directly measured with a dial-gage reading to -& mm. 11) EXPERIMENTAL RESULTS AND DISCUSSION 1) Creep Curves of a Iron and Its Alloys. Creep curves of a! iron, Fe-Si, Fe-Co, and Fe-Mo (<2 at. pct Mo) alloys usually consisted of three stages, that is transient (primary), steady-state (secondary), and accelerating (tertiary) stages. An example is illustrated in Fig. 1 for a! iron. However, in Fe-Mo alloys with more than 2 at. pct Mo, an inverse transient creepZ8 was observed as indicated in Fig. 2. The inverse behavior, which varied with the amount of molybdenum, may be due to the substructure* in the annealed specimen as was sug-

Jan 1, 1969

By Daniel C. Jackling

WHAT is written here features some of the things that I would say if I were to de- liver a Presidential address during the Annual Meeting to be held this month in New York. I am aware that custom favors written rather than vocal delivery of such a discourse; and, as this accords exactly with my own preference, I assure readers that they will never be called upon to hear these remarks spoken- anyhow, not by me. My year as President is drawing to a close. As I look back I like to classify and analyze the impressions that have been left with me. It has been a delightful and fascinating experience to me personally; I have appreciated the courtesies and aids, and have been deeply gratified at the honors accorded me. Perhaps the source of greatest satisfaction is the opportunity I have had to sense more about the provinces of this Institute and about the useful functions of the profession that it represents. For 38 years I have been a member. I served two terms as Director-one in 1914-&apos;16 and again in 1927-&apos;29. I have been honored by selection as a Saunders Medalist. I thought I was reasonably familiar with the functions, the ideals, and the activities of the Institute. But the things that I have discerned during the past year have dispelled that conceit. I still think that, a year ago, I was as well informed as most members; but since then I have had the rare privilege of executive service and insight. That has given me a perspective that I feel can be obtained in no other way-as I think the illustrious engineers who have preceded me in office will agree. I wish that I had the power to translate to every member somewhat of the feelings of pride in our organization that a year as President cannot help but instill.

Jan 1, 1939

By Joseph W. Richards

ALTHOUGH bad grammar, the above query is probably, at the present moment, good sense. Why was the Institute started and why does it continue to exist? The small group of men who worked out the original idea felt keenly the necessity of mining engineers and metallurgists getting together in order to discuss their professional problems. That necessity still exists but it does not strike the present generation of engineers so keenly because they have always had the Institute: they do not know what it is to be without it. The Institute is a great graduate school of mining and metallurgy. All of its members who have something to say worth saying are the teachers; all the rest may be learners or critics. No university or technical school can match the experience and information which the authors of its papers possess, no institution of learning has a body of potential listeners so extensive and so vitally interested.

Jan 1, 1921

By K. A. ACKLEY

The petroleum industry experienced a year of satisfactory accomplishment in Oklahoma during 1945. Crude oil production was increased, a new record for recent years was established in well completions, and refinery operations were maintained at a maximum level. Daily average crude oil production increased to 382,000 bbl., reflecting a 13.5 per cent gain compared with production during the previous pear. Total wells drilled during 1945 amounted to 2556, a gain of 28.7 per cent over 1944 Refinery throughout averaged 187,500 bbl. daily, an increase of approximately 4 percent over the preceding year.

Jan 1, 1946

By Basil B. Zavoico

PRODUCTION of crude it in the United States during 1939 totaled about 1.255,776,000 barrels, an average of 3,440,482 barrels per day, 3.41 per cent above the 1938 output of 1,214,355,000 barrels but 1.83 per cent below the record pro¬duction of 1,279,160,000 barrels, in 1937. However only the two-week shutdown of oil fields in the Southwestern States in August and September prevented the domestic crude production from establishing an all-time record in 1939. Demand for all petroleum products for the first ten months of 1939 showed an increase of 7.04 per cent over the similar period of 1938. Domestic demand for all petroleum products was particularly benefited by the increasing industrial activity, advancing 8.37 per cent above the like period of the preceding year equivalent to a volume increment of 256,810 barrels per day; with motor-fuel demand gaining 5.83 per cent and demand for all fuel oils gaining 12.15 per cent over the corresponding period of 1938. The export demand for the first ten months of 1939 was slightly below the export movements during the same period of 1938, declining 0.56 per cent. The European war was a major factor in 1939 for the petroleum industry in the United States, even if, at the end of the year, the war had not yet resulted in the expected large shipments to England and France.

Jan 1, 1940

By Harry C. Gatos, Frank J. Bachner, Mario D. Banus

The portion of the Nb-Sn phase diagram between 75 and 79 at. pct Nb at temperatures near the liquidus has been investigated by melting alloys of known composition and examining the microstmc-tzlres resulting when these melts were quenched. The Nb-Sn samples were contained in magnesia sleeves, and were mounted in a high-pressure apparatus. It was shown that Nb3Sn me1ts by a peri-tectic decomposition and that the composition of the compound Nb3Sn at the peritectic horizontal lies between 77 and 78 at. pct Nb. Analysis of the phases present in the samples was accomplished by anodic staining techniques and an electron-microbeam analyzer. DURING the past several years a great deal of work has been devoted to the Nb-Sn system, and the bulk of this work has been primarily concerned with the intermetallic phase Nb3Sn. However, the melting characteristics of Nb3Sn have not been investigated because of the difficulty in maintaining known compositions due to tin losses by vaporization, and the added difficulty of containing Nb-Sn alloys without sample-container reaction at the high temperatures involved. This paper reports on the development of a technique for containing Nb-Sn alloys under pressure high enough to prevent tin losses at temperatures in excess of the liquidus. Using this technique, melts of known composition were made and a phase diagram near the liquidus is proposed based on the microstructures resulting when these melts were quenched. EXPERIMENTAL The Nb-Sn alloys weighing 0.7 g each were prepared in the form of cylinders. Niobium powder, -200, +325 mesh, and tin shavings with a minute amount of tin powder for a binder were mixed in the desired proportions and cold-pressed at 50,000 psi in a 0.150-in. die. This cylinder was then enclosed as shown in Fig. 1, and the entire arrangement mounted in a 2.6-in. pyrophyllite tetrahedron.&apos; The desired temperatures (-2500°C) presented several problems in high-pressure container materials. Boron nitride, the usual sample holder, was found to react with niobium to form the nitride. However, MgO cans and plugs machined from refractory rods did not melt nor react with the sample. Thick tantalum contact disks were used to carry the large currents (~450 amps) to the graphite heater, since tantalum did not melt and had enough strength to prevent extrusion of the sample. It was further observed that the graphite heater and tantalum disks could not be in direct contact with the pyrophyllite because it melts and decomposes at these temperatures to kyanite and coesite (SiO2),2 the former reacting with graphite and the latter with tantalum to form the silicide. The use of a MgO outer sleeve

Jan 1, 1965

[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. D. Parks

DESPITE the handicap of reduced production in many districts, the mining industry in 1938 forged steadily ahead toward solution of its minor technical problems and has of-defected major advances in several fields. In California hydraulic mining for gold, shut down for forty years, will shortly be resumed following revision of restrictive laws. Disposal of hydraulicked ground is to be regulated by settling dams so as not to interfere with agriculture. Gold mining has been aided also by the development of a new high-efficiency dry amalgamator which applies the Ramsay mercury separator to the original de Phily process. Based on the principle that crushed ore will follow a rod into a mercury bath, this simple device is primarily adapted to dry areas and is to be available in small, multiple units suitable

Jan 1, 1939