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By Dwight E. Woodbridge

DuriNg April, Max, and June, 1910, I was in charge of an examination of the greater part of the Moa iron-ore area in Oriente Province, Cuba, on the north coast, near the east end of the island. My instructions, on arrival at the properties, were to check former estimates of tonnages and grades, and to re-examine the ore comprised in claims covering 44,727 acres. This work included the running of lines dividing the properties into co-ordinate planes, the boring of many thousand feet of holes spaced at the intersections of these co-ordinates, the taking of samples of the ore penetrated, the analysis of these samples for their various constituent minerals, and the determination of the results as to tonnages, depths, and grades, both for individual properties and for the entire group. Each section of every one of the thousand holes drilled was to be compensated for depth and grade with every other, a series of simple arithmetical calculations of no slight magnitude, the mere mechanical labor of which consumed much time, but finally resulted in giving a complete average of all the essential facts for the entire area of 18,000 hectares, Had it not been for the more than willing, active, and able co-operation of the officers of the Spanish-American Iron Co., from Charles F. Rand, President, and Jennings S. Cox, General .Manager, down to the most humble water-carrier, the work would have consumed far more time than it did. The lands thus systematically explored by me were comprised in the following denouncements: Punta Gorda, Yaminiguey, Baracoa secunda, Sagua, Moa, Yajrumaje, Lirio, and Cabanas, all of which were massed as the Moa group, so called, and cover an area of 13,832 hectares, or 34,179 acres. Some 10,000 acres additional to this was included in neighboring properties, lying between Moa and the east end of the island, the Buena Vista,

Jan 1, 1912

By G. D. Just

INTRODUCTION Large scale underground mining involves the bulk handling of fragmented material. The cost and efficiency of the mining systems is there- fore significantly influenced by material flow characteristics. Flow problems may occur in the form of ore pass blockages which interrupt the free flow at extraction openings. The costs of such delays can be readily assessed and compared to the costs incurred in reducing blockages by improved fragmentation or larger ore passes. In practice the problem is more complex than this statement suggests because it is generally un- economic to design for zero ore blockages. Another major flow problem occurs in the form of relative movement of ore and waste as the fragmented material is extracted. This produces waste dilution in the recovered ore and influences total ore recovery. This flow problem is much more complex than the ore block- age phenomena. Many questions concerning the precise flow characteristics remain unanswered because of the variability of size distributions, particle shapes, material properties and the total extraction layout and design. Model studies can provide a visual and quantitative illustration of probable flow characteristics but full scale data collection is necessary to evaluate the precision of such information. The methods and types of data obtained must be carefully selected to recover the maximum volume of useful information for operational control and future design. It is essential that honest precision levels are assigned to the data and any subsequent analyses. Grade control data may give misleading short term information on flow characteristics because of the difficulty in knowing the true grade of the mass of material before extraction commences. However, in the long term control of extraction grades is vital to the profitable operation of the mining system. The most efficient extraction design and operational schedule can only be determined after all of the facts and variables are known. This is usually only possible after the orebody has been completely extracted. However, if design and operational personnel have a full appreciation of the nature and variability of material flow under different conditions the best possible results should be achieved. The most significant features of material flow are out- lined in this paper in order to provide mine planning and mine management personnel with some of the necessary information relating to material flow. Available facts and reliable figures from selected publications are noted in association with unbiased and hopefully accurate opinions of the relevance of the data to mine design and mine system control. Possible future developments and profitable areas for research into material flow problems are also detailed. MATERIAL FLOW AND MINING METHODS The effects of material flow on the design and operation of an integrated underground ore handling system is one factor which is common to most mining methods. Analysis of the system as detailed by Just, 1980, permits the identification of unit process objectives. For example, a typical underground ore handling system as illustrated in Figure 1, involves the following unit operations:- (i) Gravity flow of ore in stope (ii) Ore extraction at base of stope (iii) Ore haulage on the production level (iv) Dumping of ore into ore pass system (v) Gravity flow of ore in the ore pass (vi) Underground crushing of ore (vii) Haulage of crushed ore to shaft (viii) Hoisting of ore to the surface. Average flow rates in each of these unit operations can be misleading due to variability in incremental capacity caused by flow blockages and machine delays. Thus to effectively analyse the probable performance of the system, it is necessary to have a measure of the flow loading and haulage rate variability. Mechanical equipment performance specifications can be used to provide such information for loading, haulage and crushing; however, in the case of the gravity flow of material field measurements are required to relate the probability of "hang-ups" to the degree of fragmentation. Factors affecting the frequency of flow stoppages are, size, distribution and cohesiveness of broken material and the geometry and size of the flow channel. Ore pass channel design is relatively simple since regular cross-sectional shapes are used

Jan 1, 1981

Jan 1, 1894

By Erwin H. Leeman, Raymond R. Rice, Gerald L. Hassler

In the past few years a great deal of preeise information has been obtained about the relation of natural gas to oil production1. The improvement of our understanding has been of great value, both in prolonging the life of wells and in providing a much needed technical background for the legal problem of proration. But there are two principal aspects of the problem of production. It is necessary to consider not only the energy available, in the form of compressed and dissolved gas and in the pressure of driving water, but also the tenacity with which the sandstone holds the oil. The amount of oil that each sand condition will produce under given conditions of gas content should be determined. Hitherto the effect of the sand has been judged by a study of the flow of each well coupled with a procedure for extrapolating the production curve; hut, as is well known to evaluation engineers, such production curves are subject to changes that are not well understood, and often are affected by outside disturbances. On the whole, the concept of "potential production" is vague principally because the influence of the sand in production is not known beyond the simple ideas of porosity and permeability. The permeability is a quantity that has only inference value where mixtures of gas and oil or of gas, oil and water are present. Excellent studies of the production of oil from reservoirs packed with unconsolidatcd sand are available2, but these studies treat largely of small-scale analogzes to a producing field, and the conclusions to be derived from them arc necessarily of a qualitative character because it is not known in what way these miniature oil fields resemble large ones.

Jan 1, 1936

By Erwin H. Leeman, Raymond R. Rice, Gerald L. Hassler

In the past few years a great deal of preeise information has been obtained about the relation of natural gas to oil production1. The improvement of our understanding has been of great value, both in prolonging the life of wells and in providing a much needed technical background for the legal problem of proration. But there are two principal aspects of the problem of production. It is necessary to consider not only the energy available, in the form of compressed and dissolved gas and in the pressure of driving water, but also the tenacity with which the sandstone holds the oil. The amount of oil that each sand condition will produce under given conditions of gas content should be determined. Hitherto the effect of the sand has been judged by a study of the flow of each well coupled with a procedure for extrapolating the production curve; hut, as is well known to evaluation engineers, such production curves are subject to changes that are not well understood, and often are affected by outside disturbances. On the whole, the concept of "potential production" is vague principally because the influence of the sand in production is not known beyond the simple ideas of porosity and permeability. The permeability is a quantity that has only inference value where mixtures of gas and oil or of gas, oil and water are present. Excellent studies of the production of oil from reservoirs packed with unconsolidatcd sand are available2, but these studies treat largely of small-scale analogzes to a producing field, and the conclusions to be derived from them arc necessarily of a qualitative character because it is not known in what way these miniature oil fields resemble large ones.

Jan 1, 1936

By D. A. Keyes

International Minerals & Chemical Corp. (Canada) Ltd. is presently exploiting by underground mining a potash-rich zone in the middle Devonian Prairie Evaporite formation near Esterhazy, Saskatchewan. Of the three main potash-bearing horizons denoted by Goudie as zones 1, 2 and 3 only the 1ower. two are present at Esterhazy and mining is confined to the lower or zone 1 horizon. The area in which the evaporites were deposited, although flanked on the west by a zone of geosynclinal deposition and tectonic activity, has been subjected to only very gentle epeirogenic activity. The sylvinite ore is coarsely crystalline and occurs in well-defined beds. The halite, sylvite and insoluble content of the ore bears a direct relationship to the lithological units, but the carnallite cuts across the beds. Local concentrations of salt produce blank spots in the ore horizon. Some of these appear to be salt-filled, post-ore channels and cracks while others have been formed by brines emanating upward from below the ore. INTRODUCTION International Minerals & Chemical Corporation (Canada) Ltd. is operating an underground potash mine near the town of Esterhazy in eastern Saskatchewan. The deposit was discovered by IMC in 1955. Subsequent drilling outlined extensive high-grade reserves, and in 1957 shaft sinking and plant construction began. Production from Yarbo No. 1 Shaft commenced in September, 1962 and quickly reached the initial capacity of one million tons of muriate product per year. Production is currently being expanded to 1.6 million tpy. The single mining level is 3140 ft below the surface at No. 1 Shaft. GENERAL GEOLOGY The Esterhazy district lies within the Interior Plains region of Canada and on the northeast rim of the Williston Basin (Fig. 1). Average dip of the rock formations in this area is about 40 ft per mile to the southwest. The potash ore occurs in the Prairie Evaporite formation of the Middle-Devonian Elk Point Group. The Prairie Evaporites are overlain by 3000 ft of Paleozoic shales and limestones and by Jurassic and Cretaceous sandstones and shales (Fig. 2).

Jan 1, 1967

By C. B. Dudley

In October, 1878, and again in February, 1881, I had the honor to make public, through the medium of the American Institute of Mining Engineers, the results of an extended study of steel rails which had been in service, and which mere taken for the purpose from the tracks of the Pennsylvania Railroad Company. These studies appeared in three papers. In the first of these papers the question. what kind of steel is least liable to fracture or disintegration in the track, was the principal one considered. In the second paper the question discussed was, does the power of steel to resist wear increase with the hardness ? In the third paper the relation between wear and the chemical and physical properties of the metal was the principal point considered. The general results arrived at, or the cooclusions reached, were, as follows: 1. That a mild steel is less liable to fracture, and if properly made, less liable to crushing or disintegration in the track than a harder steel. 2. That the wearing-power of steel in rails not only does not increase as hardness increases, but, on the contrary, diminishes; or, in other words, that a mild steel gives less loss of metal under the same service than a hard steel. These conclusions may be briefly stated in a single sentence—namely, in rails mild steel is not only less liable to fracture and disintegration in the track, but it also gives longer life, or wears more slowly under the same traffic; than harder steel. It is perhaps hardly necessary to add that by mild steel is meant steel

Jan 1, 1891

By W. H. Emmons

MANY mineral veins occupy faults, and movements on certain warped fault planes have resulted in openings. On normal faults the [ ] steeper parts have the widest openings, and on reverse faults the flatter parts have the widest openings. Theoretically the width of the opening is the sine of the angle of deflection times the amount of movement on the fault plane, but actually the widths of some of the openings are probably less because of readjustments of walls along joints or of other readjustments. The first treatment of the subject seems to have been in a book on mineral veins by John Leithart, published in Newcastle, England, in 1838. Later the subject was treated in various texts published in Germany, in England, and elsewhere. The subject was not given much prominence in the earlier American literature on economic geology, but has interested several workers in that field in the past decade. In this paper examples of districts showing ore shoots on warped faults, with relations noted, are described. Fault veins of the three depth classes of veins are noted. Many epithermal veins are in normal faults, and commonly the larger ore shoots are in their steeper portions. Many mesothermal veins are in reverse faults and many others are in normal faults. The flatter parts of veins in reverse faults are commonly wider than the steeper parts, although they are not always as rich as the steeper segments of the veins. There are not many hypothermal veins in faults of measured displacement.

Jan 1, 1943

By F. M. Simonds, E. Z. Burns

The Rawley property is located in the Kerber Creek mining-district, Saguache county, Colorado, at an elevation of 10,600 ft. (See sketch-map, Fig. 1.) Ore was found in this vicinity as early as 1880, and claims covering a large area were located and in many instances patented. The ores, however, being of comparatively low grade, and the nearest railway station, Villa Grove, being some 20 miles away, it is extremely doubtful whether any considerable amount of ore was ever handled at a profit. It is safe to say that several hundred thousand dollars were spent (a large part in building mills) previous to 1902-03. About that time a very capable promoter gathered together a group of these claims and interested some New York people, who had had no previous mining experience, in the purchase of these claims. Following the organization of a company, this promoter became General Manager. As often happens under such conditions, the first step was to erect a mill to treat 100 tons per day. It may not be fair to this enterprise to say that the failure which followed might have been foretold, simply on general principles, but this much is certain—the water supply fluctuates in the course of a season through a wide range and for a considerable portion of the year was inadequate to run this mill at capacity. Further, it is currently reported that some of the mill foundations were placed on ice. However true this statement may be, it is a fact that, when first inspected by us, many of the belts in the mill were held on'their pulleys by means of idlers. A shut-down followed, with a material re-adjustment of interests, at which time we became consulting engineers for the company.

Jan 1, 1914

By E. S. Hutchinson

The subject of the influence of coal-dust in mine-explosions has received considerable attention both in England and on the continent of Europe, but until the recent disaster at Pocahontas, Va., it seems not to have been of special interest to engineers in this country. The reason, perhaps, is that most of our bituminous mines are worked by short shafts, slopes and drifts; few have been specially dry; and the explosions that have occurred could readily be traced to fire-damp with 110 complicated circumstances. The object of the present paper is to bring together, for the convenience of members of the Institute, the principal English opinions upon this important subject. Messrs. Lyell and Faraday, in their report to the Home Secretary," in England, on the Haswell Colliery explosion in 1844, seem to have been the first to point out that dust fed the flame originating in a

Jan 1, 1885

By William F. Butler, Mo-Hung Che

DEVELOPMENT OF MONEY AND MONEY STANDARDS This chapter is concerned with the rise, and then the decline and fall, of gold and silver as monetary metals. As a first step in tracing the history of this process, it is necessary to consider the nature of money, and the manner in which different forms of money have developed over the centuries. The origins of money go back into deepest antiquity. Once men ceased to be pure nomads and entered into even a rudimentary form of society such as clans or tribes, money had to be invented The first step was barter as farmers or hunters swapped their surplus products for things produced by artisans such as shoes, clothing, and simple tools. But such barter trading is inconvenient even in primative societies It is difficult to match up buyer and seller at any point in time There are problems in arriving at viable and acceptable terms of exchange. The accumulation of savings-wealth-is complicated. No one can be sure that a pile of furs, or wheat, or certainly fish or game can be used in the future to trade for other goods or services. So even prehistoric man saw the need for money. There was a need first for something to serve as a medium of exchange This was an essential first step in the process of specialization-or the division of labor. A farmer, a hunter, or a shoemaker could only devote his full efforts to his trade if he could be sure that he could exchange his surplus production for the other things he needed for existence. This required a medium of exchange-a form of money which would be broadly acceptable. Money was needed for two other reasons Some system of market prices was essential to facilitate the exchange of goods and services. This required some form of common denominator-some standard of value-to govern the exchange process. And there was also need for something to serve as a store of value, a place to put any excess production (savings) with the assurance that it can be used in the future to acquire a general range of goods and services. As a result, money, in one form or another, developed at a very early state in civilization. Yet the centuries have been marked by a search for a form of money which will possess in full measure all of the attributes in money-a reliable and universally acceptable medium of exchange, standard of value, and store of value. -A wide variety of things have been used as money at one time or another: shells, beads, stones, feather, metals, and even the teeth of sharks and dogs. Some of these things were obviously of little or no practical value. They were used because people had confidence in their continued acceptance as a medium of exchange. As the world evolved and as trading ex-

Jan 1, 1976

By Otto H. Henry, J. J. Cordiano

Though powder metallurgy is one of the oldest of metallurgical processes, it is in its infancy as a branch of the modern field of metallurgy. As early as 3000 B.C., the ancients produced implements and weapons of iron by reducing iron ore in a charcoal fire and forging the resultant sponge while still hot into the desired shape. Melting and casting soon superseded the powder metallurgy practice, and it was not until the turn of the twentieth century that powder metallurgy was applied to the commercial manufacture of tungsten lamp filaments. From this beginning, the use of the powder metallurgy process spread" to the manufacture of porous oil-impregnated bearings, cemented carbide tools, contact points, diamond grinding wheels, clutch facings, starter brushes, resin-bonded radio cores, magnets, metallic filters, and other parts. More recently, and particularly during the present war, there has been a definite trend toward the manufacture of machine parts by this process in competition with the more conventional fabricating methods. Notwithstanding these many developments, scientific progress has been slow. While many articles on powder metallurgy have appeared in the press and various publications, there have been too few contributions to our technical societies, with the result that there is a dearth of the type of information necessary for the full development of this science. It is of primary importance that the results of research and development be freely disseminated if powder metallurgy is to realize its fullest potentialities. Purpose of Investigation Excluding the refractory metal field, all commercial powder metallurgical products made by a cold compressing and sintering operation contain voids. These voids can be substantially eliminated by subsequent severe working and heat-treatment, but ' such practice has not proved economical in most applications. By applying heat during the compressing operation, plastic deformation of the powder particles is substantially increased, and the resultant compact or briquette is practically free of voids. However, hot-pressing has many attendant problems, which at present preclude its use in the manufacture of precision parts. The more important of these are to devise: 1. A die steel capable of withstanding high pressures at elevated temperatures. 2. A high-temperature lubricant capable of preventing excessive die wear and welding of the compact to the die walls. 3. A method of retaining a neutral or reducing atmosphere in the compacting zone of the die assembly. 4. A means of ejecting the hot-pressed specimen into a neutral atmosphere until reasonably cold.

Jan 1, 1946

By Otto H. Henry, J. J. Cordiano

Though powder metallurgy is one of the oldest of metallurgical processes, it is in its infancy as a branch of the modern field of metallurgy. As early as 3000 B.C., the ancients produced implements and weapons of iron by reducing iron ore in a charcoal fire and forging the resultant sponge while still hot into the desired shape. Melting and casting soon superseded the powder metallurgy practice, and it was not until the turn of the twentieth century that powder metallurgy was applied to the commercial manufacture of tungsten lamp filaments. From this beginning, the use of the powder metallurgy process spread" to the manufacture of porous oil-impregnated bearings, cemented carbide tools, contact points, diamond grinding wheels, clutch facings, starter brushes, resin-bonded radio cores, magnets, metallic filters, and other parts. More recently, and particularly during the present war, there has been a definite trend toward the manufacture of machine parts by this process in competition with the more conventional fabricating methods. Notwithstanding these many developments, scientific progress has been slow. While many articles on powder metallurgy have appeared in the press and various publications, there have been too few contributions to our technical societies, with the result that there is a dearth of the type of information necessary for the full development of this science. It is of primary importance that the results of research and development be freely disseminated if powder metallurgy is to realize its fullest potentialities. Purpose of Investigation Excluding the refractory metal field, all commercial powder metallurgical products made by a cold compressing and sintering operation contain voids. These voids can be substantially eliminated by subsequent severe working and heat-treatment, but ' such practice has not proved economical in most applications. By applying heat during the compressing operation, plastic deformation of the powder particles is substantially increased, and the resultant compact or briquette is practically free of voids. However, hot-pressing has many attendant problems, which at present preclude its use in the manufacture of precision parts. The more important of these are to devise: 1. A die steel capable of withstanding high pressures at elevated temperatures. 2. A high-temperature lubricant capable of preventing excessive die wear and welding of the compact to the die walls. 3. A method of retaining a neutral or reducing atmosphere in the compacting zone of the die assembly. 4. A means of ejecting the hot-pressed specimen into a neutral atmosphere until reasonably cold.

Jan 1, 1946

INTERNATIONAL ENGINEERING CONGRESS This Congress will be held under the auspices of five National Engineering Societies, of whi h the Institute is one. The sessions will be held in 11 sections and the proceedings will be published in 10 volumes of 500 pages each, of which Volume 8 will contain the papers and proceedings on Mining Engineering and Metallurgy. The membership fee of $5 will entitle the holder to the volume of General Proceedings and Index, and, in addition thereto, any other single volume chosen. Other volumes may be subscribed for according to a sliding scale depending upon the number of volumes taken. The Institute will have a meeting in San Francisco during 1915, and it is desirable for our members to join the International Engineering Congress at in early date in order that their support of the enterprise may be given in its early stages, when it is most needed.

Jan 2, 1914

By W. F. Holbrook, T. L. Joseph

The problem of sulfur control is important in all blast-furnace operations but particularly for certain grades of steel because of the rigorous specifications. During the past decade the tendency has been to produce pig iron and hot metal of lower sulfur content. As most of the sulfur in the iron originates in the fuel, the use of high-sulfur coke demands modifications in practice to meet sulfur specifications. While it is generally known that high temperatures and more basic slags favor desulfurization, operators as a rule produce the most acid slag that will permit proper desulfurization. The viscosity of blastfurnace slag has been thought to be related to desulfurization and has been investigated by Feild and Roysterl, also McCaffery and his associates*, but apparently no systematic effort has been made to determine the relative desulfurizing powers of slags over the range of composition encountered in practice. Development of Testing Method Because slag and metallic iron are immiscible, the desulfurization reaction is heterogeneous, occurring only at the interfaces between slag and metal bodies. In the blast furnace the newly reduced iron, containing FeS, descends through the slag bath probably either as small drops or streams, at the interfaces of which desulfurization occurs. After its descent through the slag the iron collects to form a bath of metal, at the top surface of which desulfurization reaction probably occurs. These two steps have been thought to account for all desulfurization in the blast furnace. Kinney3 found that metal removed from the blast furnace just above the tuyeres contained three to four times as much sulfur as the iron at cast. Herty and Gaines4 conclude that most of the sulfur is removed while the metal is passing through the slag. Mund, Stoecker

Jan 1, 1936

By W. F. Holbrook, T. L. Joseph

The problem of sulfur control is important in all blast-furnace operations but particularly for certain grades of steel because of the rigorous specifications. During the past decade the tendency has been to produce pig iron and hot metal of lower sulfur content. As most of the sulfur in the iron originates in the fuel, the use of high-sulfur coke demands modifications in practice to meet sulfur specifications. While it is generally known that high temperatures and more basic slags favor desulfurization, operators as a rule produce the most acid slag that will permit proper desulfurization. The viscosity of blastfurnace slag has been thought to be related to desulfurization and has been investigated by Feild and Roysterl, also McCaffery and his associates*, but apparently no systematic effort has been made to determine the relative desulfurizing powers of slags over the range of composition encountered in practice. Development of Testing Method Because slag and metallic iron are immiscible, the desulfurization reaction is heterogeneous, occurring only at the interfaces between slag and metal bodies. In the blast furnace the newly reduced iron, containing FeS, descends through the slag bath probably either as small drops or streams, at the interfaces of which desulfurization occurs. After its descent through the slag the iron collects to form a bath of metal, at the top surface of which desulfurization reaction probably occurs. These two steps have been thought to account for all desulfurization in the blast furnace. Kinney3 found that metal removed from the blast furnace just above the tuyeres contained three to four times as much sulfur as the iron at cast. Herty and Gaines4 conclude that most of the sulfur is removed while the metal is passing through the slag. Mund, Stoecker

Jan 1, 1936

By C. P. Fiske

THE pottery of the New Jersey Zinc Co. (of Pa.) is equipped to make three classes of refractories; namely, spelter vessels, spelter condensers; and high-grade fire-brick. The most important of these are the spelter vessels, on account of the extreme severity of the service which they must perform, necessitating great care in the selection of materials and in the whole process of manufacture. Next to the spelter vessels in importance? come the condensers, as large numbers are used in the manufacture of spelter, and improvements m quality result in material decreases in working cost. , While the fire-brick which form the laboratory, or high-temperature portion of the spelter furnaces, are placed at the foot of the list, they-are nevertheless of much importance, since high quality will decrease the frequency of the always expensive shutdowns for repairs. To promote simplicity, the manufacture of these three products will be described separately in this paper, except in so far as materials and the crushing and handling system common to all are concerned. Materials Bond Clay.-The bond clay used entirely at the Palmerton pottery is a St. Louis clay furnished by the Grand View Fire Clay Co. It is stored in a system of covered bins, and no attempt is made to weather -it in the, accepted sense of the term " weathering." Some years ago our clay was weathered before pugging, but we did not find the benefit sufficient to offset the additional handling and the loss. of clay incurred. Furthermore, we believe that the rotting of the pugged mix (described later), accomplishes the same results to better advantage. That there is some action taking place in the clay while stored in the covered bins, however, is, evidenced by an increase in volume which at times has caused damage to the retaining walls of the bins. We have at present a stock of bond clay weathering in the open, and when this is put into service an opportunity will be afforded for making comparisons-with the clay as usually handled.

Jan 10, 1917

By Paul E. Richardson, Edwin E. Maust

Cyclic voltammetry and surface potential (photovoltage) measurements have been carried out on galena electrodes in sodium tetraborate solutions with added HC1 and NaOH to adjust the pH over the range 2 to 13. The first technique shows that the surface species formed on moderate anodic polarization and reduced on subsequent cathodic polarization are the same over the entire pH range. At anodic potentials, a soluble metal species and excess sulfur are formed; at cathodic potentials, sulfur is reduced to a soluble species. More importantly, excess surface sulfur is formed spontaneously under zero current conditions in alkaline solutions. This has been shown to occur on both polished surfaces and on virgin surfaces produced by in situ cleavage under the electrolyte. The photovoltage gives some insight into the charge and potential distribution at the galena surface. This is found to depend on past electrochemical history and the n- or p-type semiconducting character of the electrode and is interpreted in terms of changes in the surface stoichiometry that occur during reduction or oxidation. The effect of surface stoichiometry on subsequent xanthate interactions is discussed.

Jan 1, 1976

By William F. Boericke

RESEARCH in the modern refractories laboratory has two practical ends in view-to develop refractory materials for the metallurgist that will meet particular operating difficulties more effectively and to ?manufacture these refractories at a cost sufficiently low to make their use economical to the metallurgist. At the research laboratories of E. J: Lavino and Co., at Plymouth Meeting, Pa., the technical staff, under Dr. Gilbert E. Seil, is giving principal attention. to an. exhaustive investigation of the following factors in refractories:

Jan 1, 1931

By AIME

DURING the happy and peaceful years between the Treaty of Versailles and the third New Deal, metallurgy became one of the most cosmopolitan of the sciences. Any metallurgist can name some twenty or thirty scientists whose work, in this country, in England, in Germany, or in France, Sweden, Italy, or Japan was as well known in other parts of the metal-producing and metal using world as it was locally, despite the fact that many of these men never left their native land. One of these metallurgical cosmopolites is Augustus Braun Kinzel, former Chairman of the Iron and Steel Division, A.I.M.E., and now a Director of the Institute. Gus Kinzel, however, is not only a cosmopolite by reputation; he is also a cosmopolite in fact. For many years he commuted at least twice a year between New York and the rest of the world; he is, therefore, not only an expert on the art and science of metallurgy but is equally expert in world travel and can expound with authority on the comparative quality and especially on the cuisine of the great prewar steamship lines; and being a true cosmopolite, he knows, as well as he knows the iron-chromium diagram, the best vintage years in the Gironde, Cote d'Or, and Saone-et-Loire departments in France and along the banks of the Moselle and Rhine in Germany.

Jan 1, 1946