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By B. B. Zavoico, J. G. H. Crump, P. P. Gregory

West Texas was the scene of greatly increased oil activity during 1937, producing 75,743,000 bb1.l in that year as compared with 61,901,-000 bb1.2 in 1936, an increase of 22.36 per cent. The annual total of wells completed increased from 15863 in 1936 to 28062 in 1937, an increase of 76.92 per cent. Of the total completions in 1937, 2464 were oil wells,2 11 gas wells2 and 331 dry holes.2 The marked increase in the number of oil wells completed in West Texas during 1937 had a substantial effect upon the daily average production per well, which decreased 20.84 per cent from December 1936, when a total of 5310 wells3 produced 5,236,467 bbl.3 for an average of 31.81 bbl. per well per day to December 1937, when 7571 wells2 with a total production of 5,910,257 bb1.2 averaged 25.18 bbl. per well per day. Drilling blocks and checkerboard acreage were being acquired following geophysical work in the northern end of the Permian Basin area, composed of Bailey, Cochran, Hockley, Yoakum and Terry Counties, presaging extension of active development northward. During 1937, at one time 30 geophysical crews were working in West Texas, and an average of 15 to 20 crews was active in this area throughout the year. Discoveries Wasson-Denver Field.—Wasson-Denver field in Gaines and Yoakum Counties was the outstanding field discovery of the year. Production is from porous limestone found at about 5000 ft., and an average well is good for from 300 to 500 bbl. of crude oil per day through 3/4-in. choke. The discovery well was drilled by A. G. Carter and others on the Wasson Ranch, Gaines County, and the field has since been extended into Yoakum County. At the year's end 21 wells had been completed, producing

Jan 1, 1938

By C. W. Gennet

Announcement was made in the spring of 1926 that the Boston & Maine R. R. Co. had contracted with the well-known German steelmakers, Messrs. Fried Krupp, for the manufacture of 15,000 tons of basic open-hearth steel rails at the Rheinhausen Works, for delivery to Boston, Mass. The manufacture of rails in the United States has for many years been almost a national pride, and as this feeling is chiefly the result of a long-time liberal and consistent patronage of American rails by American railroads, it is not strange that this somewhat unusual announcement should arouse more than ordinary interest. Since the end of the World War, the importation of foreign rail has been fairly large, principally because the newly created economic conditions have rendered some American competition more difficult, but the tonnage imported, for the most part, has been made up of small orders for miscellaneous use; and the contract referred to constitutes the largest single importation of foreign rail in over ten years. In 1915, the Algoma Steel Co. of Sault Ste. Marie, Canada, supplied the Illinois Central R. R. with 30,000 tons of rails,' and various other American roads with smaller amounts. In 1902, 1903 and 1904, large tonnages of rail from abroad were purchased, the Louisville & Nashville R. R. alone obtaining 30,000 tons from German mills. It is the object of this paper to present, in what is believed to be a new and concise form, figures showing the production and consumption of rails in the United States, and to record some of the testing and inspection results of the recent Krupp rails; also, to direct attention to two quite unique departures from American practice that were regular features of the Krupp process and which are worthy, it is thought, of careful study. Production and Consumption of Rails in the United States Table 1 shows the tonnage of rail produced in the United States and the amount imported, exported, and consumed by years since 1849. That, evidently, was the first year of record, for the statistics of the American Iron and Steel Institute and its predecessor, the American Iron and

By Henning Nielsen

SIX weeks ahead of schedule, the International Nickel Co. of Canada Ltd. has brought a 30-mile rail line into the newly born town of Thompson, Manitoba. Its construction spurs the development of a rich new mining region slated to become the world's second largest nickel-producing area-exceeded only by Inco's Sudbury, Ont., workings. Two mines, the Thompson and the Moak Lake, will be opened to meet International Nickel's scheduled annual production goal of 385 million lb of refined nickel by 1961. Accomplishment of this aim will mean an additional 75 million lb of the metal available to consumers. In addition, stepped-up out- put of Inco's Sudbury holdings may increase this figure by another 25 million lb. (For an earlier report on these developments see MINING ENGINEERING News, January 1957).

Jan 12, 1957

By Charles B. Dudley

DEAR SIR: It is now nearly three years since my first report to you on the subject of steel rails was written. That report, as you will remember, dealt principally with the question of the relation between the chemical composition and physical properties of steel rails end their power to resist crushing and fracture in actual service. Other matters were referred to or touched upon in that report, but the main question was, Why do some rails crush or break in service while others do not? Yon will doubtless remember that the principal conclusion arrived at was, that the softer rails are less liable to Crush or break in service than the hard ones. Or, in other words, so far as conclusions could be drawn from the chemical analysis and physical test of 25 samples of steel rails which had actually been in service, these conclusions were that those rails which have the smaller amounts of carbon, phosphorus, silicon, and manganese are less liable to crush or break in service than those which have larger amounts of these elements. Or, again, looked at in the light

Jan 1, 1881

By M. E. Wadsworth, L. H. Raby, A. S. Peck

Infrared spec troscopy was used to study the adsorption of oleate collector on three varieties of hematite. Each of the minerals was found to react with either oleic acid or a solution of sodium oleate to form a mineral cation-collector anion chemisorbed layer at the solid-liquid interface. The chemisorption reaction displaced surface hydroxyls and was found to be pH dependent. The infrared band characteristic of the antisymmetrical C = 0 structural group of chemisorbed oleate appears between 1520 and 1540 cm-'. Evidence is presented which shows that molecular filming of the mineral surfaces with un-dissociated oleic acid precedes chemisorption. Infrared absorbance is correlated with the flotation behavior of the mineral. Adsorption processes are usually classified into two types which are distinguished and character- ized by the nature of the bond formed between the adsorbate and adsorbent. The process in which molecules chemically bond to solid surfaces is termed activated adsorption or chemisorption. If only weak van der Waals forces bind the molecules to the surface then the process is termed physical adsorption. Chemisorption is of primary interest in flotation systems since selectivity may be obtained if a single mineral is rendered air-avid by a specific collector mineral adsorption reaction. In previous studies infrared spectroscopy was used to define the mechanisms involved in the adsorption of oleic acid and sodium oleate on fluorite, barite, and calcite. Infrared techniques were particularly useful since adsorbed monolayers were identified in situ. Further, the infrared method permitted identification of reaction products in the solid, liquid, and vapor phases of the systems. The chemisorption reactions displaced F- from fluorite, SO4 from barite, and CO3 from calcite. This investigation was pursued in an effort to characterize and interpret the adsorption processes for synthetic hematite, compact red hematite, and specular hematite (crystalline hematite). Adsorption tests were performed using either oleic acid or

Jan 1, 1967

Edward S. Simpson, Perth, Western Australia (communication to the Secretary): In 1896 the East Coolgardie gold-field was divided into three fields, viz. : Area, square miles. Officia1 Centers. (1) East Coolgardie,. . 634 Kalgoorlie. (2) Broad Arrow,. , 588 Kurawa. (3) Northeast Coolgardie,. 22,960 Kanowna. The whole of the area embraced by the eastern gold-fields is covered with late Tertiary sands and gravel, with occasional beds of clay shales. These mostly overlay granite which occasionally shows through in small round hills. At Coolgardie, Kalgoorlie and other mining centers, belts of diorite, serpentine and highly metamorphosed sedimentary rocks appear on the surface. The rainfall at Kalgoorlie in 1897 was 4.75 inches. That the climate has not always been so arid is evidenced by the recent discovery at Coolgardie (only twenty-five miles away) in the late Tertiary formations of a thick bed of brown coal, containing numerous fossil fern-leaves. As assayer and mineralogist to the Government of Western Australia I have had occasion to examine a large amount of the Kalgoorlie ores, both in Perth and at the mines at Boulder itself. The only tellurides I have been able to determine are

Jan 1, 1899

Jan 1, 1901

By Oscar M. Wicken

The mineral magnesite (MgCO3) if pure would consist of 47.7 pct MgO and 52.3 pct CO2. It is one of the calcite group of rhombohedral carbonates which includes calcite (CaCO3), siderite (FeCO3), rhodocrosite (MnCO3), and smithsonite (ZnCO3) among others. The members of this group enter into a wide range of substitutional solid solutions, whose range is still imperfectly known.* MgCO3 and FeCO3 appear to form a complete series of which breunnerite (ferroan magnesite) is a well known variety. Because of the considerable difference in size of the Ca and Mg ions, there is only a limited range in substitution in the MgCO3-CaCO3 series. (Dolomite, not strictly a member of the calcite group, may be regarded as an ordered structure developed when Ca: Mg is approximately 1:1.) The practical consequence of these relationships is that the lime carbonates (calcite and dolomite) are commonly present in magnesite deposits chiefly as mechanical mixtures. Magnesite may be either crystalline or "amorphous" (cryptocrystalline). The crystalline form has a hardness of 3.5 to 4.0. The color may range from white to black through shades of yellow, blue, red or gray. It is rarely found pure but generally contains variable amounts of iron, lime, and silicate minerals. Color cannot be used as an index of purity except under specific local conditions in a single quarry. In a given quarry an experienced man may be able roughly to grade magnesite by intuitively assessing such features as crystallinity and color. Crystalline magnesite occurs in larger deposits, but the cryptocrystalline variety is more common. The latter is fine-grained and compact and shows no cleavage; often it is descriptively called "bone magnesite." The fracture is usually conchoidal, and hardness is 3.5 to 5.0. It is normally white, but sometimes it is light yellow to orange or buff because of included impurities. In addition to lime and iron, which may be present in small amounts, silica may be present as inclusions of serpentine, quartz, chalcedony, or other minerals. In general, commercial deposits of "amorphous" magnesite have lesser amounts of accessory minerals than does crystalline magnesite. The specific gravity of "amorphous" magnesite is 2.90 to 3.0. Pure, crystalline magnesite has a specific gravity of 3.02, but iron carbonate, commonly present, raises the specific gravity to somewhat higher values. Magnesite dissociates, when sufficiently heated, into magnesia (MgO) and carbon dioxide. Either simultaneously or upon further heating the magnesia develops a crystalline structure identical with that of the natural mineral, periclase, which occurs sparingly in nature but not normally in workable deposits. Brucite is another magnesium mineral capable of being directly reduced to magnesia by heat alone. Brucite (Mg(OH)2) has been mined for the production of various grades of magnesia. It theoretically contains 69.1 pct MgO and 30.9 pct H2O. It may be white, but is generally blue or green with a gray cast. It has a translucent appearance. The mineral is soft (hardness, 2.5), and has a specific gravity of about 2.4. Nomenclature of Products The word "magnesite" literally refers to the natural mineral, but common usage has applied it plus a prefatory word to two other

Jan 1, 1960

As one surveys the extensive taconite operations on the Mesabi Range, he may find it difficult to believe that only 15 years ago, the iron ore mining industry here was staring at its own imminent demise. Due to the high demands for iron ore during World War II the postwar period of 1946-1950, and the subsequent "police action" in Korea, there was rapid consumption of the Mesabi's already depleted ores, and some economists were giving the Range only 20-25 years of life. In the 13-year period 1941-1953, more than 850 million tons of iron ore were shipped to steel mills, an amount almost equal to the total production during the preceding 30 years. Proven ore reserves dropped from 1.1 billion tons in 1940 to 8.3 million tons in 1954, the largest decrease being recorded in the famed direct shipping ores.

Jan 9, 1968

By Kenneth A. Gutschick, Robert S. Boynton

Lime has become a very general loosely used term that includes virtually all finely divided types of limestone as well as burned forms of lime. However, actually (and according to Webster) lime is only calcined limestone (known as quicklime, calcium oxide, or calcia). It also embraces the secondary product of quicklime-namely hydrated lime or slaked lime (calcium hydroxide). Fundamentally there are two basic types of limestone-high calcium and high magnesium (dolomitic). The dolomitic quicklimes and hydrated limes correspond to their "high calcium" counterparts in terminology. The only difference is that the dolomitic types are a combination of the elements, calcium and magnesium, whereas high calcium limes contain only 0.5 to 2 pct of magnesium. Both types, which are made through calcination at high temperatures, are shown chemically as follows: [ ] In the above reactions either type of limestone is burned (calcined) in furnaces known as lime kilns so that the carbon dioxide content of the stone is expelled as a gas. With high calcium limestone 44 pct of the weight of the stone is lost; with dolomitic limestone the loss is 48 pct. Also, both reactions are chemically reversible since quicklime absorbs carbon dioxide readily and in so doing transforms itself back to the original carbonate form. Most quicklimes correspond in size to the original rock, which varies from one to eight inches, depending upon the type of kiln employed. Slight shrinkage occurs during calcination. A few limestones when calcined will decrepitate (break down) into a fine powdery form; however, chemically it is the same as the pebble or lump-sized material. For some uses the lumps of quicklime are pulverized and packaged. Since quicklime has great affinity for moisture and carbon dioxide, it is perishable. When it absorbs moisture and CO2 slowly from the atmosphere, the resulting product is "airslaked." Consequently, it must be stored in dry, moisture-proof areas that are free from CO2. Because of its fugitive nature, it is usually consumed within a few weeks after manufacture. A more stable form of lime is hydrated lime-commercially made by adding water to the quicklime until the lumps break down into a fine, white powder. This product, which is usually packaged, can be stored more safely; and many of its uses are interchangeable with quicklime. The irreversible chemical reactions of hydrated lime for both high calcium and dolomitic types are: [ ]

Jan 1, 1960

By E. G. Banks

THIS paper is presented in the belief that metallurgists and chemists will be interested in the practice of grinding in tube-mills in connection with stamps, especially since the records of working here given extend over a lengthy period of time (since May, 1905). The ore from the Waihi mine-more especially that produced in the upper levels-contains a large proportion of hard, chalcedonic quartz, and the gold exists in an exceedingly fine state, conditions which necessitate very fine crushing in order to ob¬tain a high extraction of the precious metal. Before the introduction of tube-mills at the 90-stamp Waihi mill, it was found necessary to stamp through 40-mesh (1,600 holes per sq. in.) woven wire-screens, having a fairly high discharge. The pulp then graded

Jan 1, 1907

By Donald W. Scott

This paper describes the application of ore-dressing methods to the reclamation of milled frit from over-spray, or waste, porcelain enamel. Frit is the name given by enamelers to a granulated glass produced by the smelting and subsequent water quenching of various ingredients capable of forming a glass, usually including a compound to produce opacity. It is the major component of porcelain enamel, and normally commands a price ranging from 7 to 12 cents a pound. In the *preparation of a white enamel slip, usually 6 or 7 parts of clay, 2 parts of opacifier, small amounts of electrolytes, in some cases inorganic color stabilizeis and organic dyes, and 35 parts of water are added to 100 parts of frit; the mixture then is milled to a fineness of the order of 92 to 95 pct through a 200-mesh sieve. The frit forms the base of the enamel; the opacifier imparts opacity or reflectance; the clay suspends the frit while in slip form and serves as a binder in bisque form (dry and unfired); and the electrolytes control the workability. Spraying is used commercially, in many cases, to apply the finish coat of enamel to the ware, prior to drying and firing. In the spraying operation, only about 50 pct, by dry weight, of the enamel slip adheres to the surface of the ware, the remainder forms the over-spray. From 1/2 to 2/3 of the overspray goes up the flue where it is lost or recovered, depending on whether the plant is equipped with a dust-collecting installation; the coarser portion of the over-spray is collected in the spray booth. The former product is termed flue reclaim enamel, and the latter booth reclaim enamel. Although the spraying operation is done in specially constructed booths, which are partially or completely enclosed, it is extremely difficult to keep out contaminating dirt, which joins the reclaim. Some present-day large enameling plants use 20 tons of frit a day, of which 10 tons go into reclaim with a potential value of $1400 to $2400. When two-coat finish enamels were common, the reclaim was used satisfactorily for the undercoat, but the relatively recent advent of one-coat finish enamels prevented use of the reclaim because, even when blended with first-run enamels, it gave dirty finishes with poor gloss. It was thought that the pitting and specking encountered with reclaimed enamels were caused by the contaminating dirt, and that the poor gloss was caused, primarily, by the high clay content; more clay usually was added to give proper suspension properties to the slip when the reclaim was used. A clay content in excess of about 10 pct usually imparted refractoriness to porcelain enamels. Present-day one-coat porcelain enamels must combine high gloss and opacity with freedom from surface defects. Methods of beneficiating the over-spray,

Jan 1, 1948

By Donald W. Scott

This paper describes the application of ore-dressing methods to the reclamation of milled frit from over-spray, or waste, porcelain enamel. Frit is the name given by enamelers to a granulated glass produced by the smelting and subsequent water quenching of various ingredients capable of forming a glass, usually including a compound to produce opacity. It is the major component of porcelain enamel, and normally commands a price ranging from 7 to 12 cents a pound. In the *preparation of a white enamel slip, usually 6 or 7 parts of clay, 2 parts of opacifier, small amounts of electrolytes, in some cases inorganic color stabilizeis and organic dyes, and 35 parts of water are added to 100 parts of frit; the mixture then is milled to a fineness of the order of 92 to 95 pct through a 200-mesh sieve. The frit forms the base of the enamel; the opacifier imparts opacity or reflectance; the clay suspends the frit while in slip form and serves as a binder in bisque form (dry and unfired); and the electrolytes control the workability. Spraying is used commercially, in many cases, to apply the finish coat of enamel to the ware, prior to drying and firing. In the spraying operation, only about 50 pct, by dry weight, of the enamel slip adheres to the surface of the ware, the remainder forms the over-spray. From 1/2 to 2/3 of the overspray goes up the flue where it is lost or recovered, depending on whether the plant is equipped with a dust-collecting installation; the coarser portion of the over-spray is collected in the spray booth. The former product is termed flue reclaim enamel, and the latter booth reclaim enamel. Although the spraying operation is done in specially constructed booths, which are partially or completely enclosed, it is extremely difficult to keep out contaminating dirt, which joins the reclaim. Some present-day large enameling plants use 20 tons of frit a day, of which 10 tons go into reclaim with a potential value of $1400 to $2400. When two-coat finish enamels were common, the reclaim was used satisfactorily for the undercoat, but the relatively recent advent of one-coat finish enamels prevented use of the reclaim because, even when blended with first-run enamels, it gave dirty finishes with poor gloss. It was thought that the pitting and specking encountered with reclaimed enamels were caused by the contaminating dirt, and that the poor gloss was caused, primarily, by the high clay content; more clay usually was added to give proper suspension properties to the slip when the reclaim was used. A clay content in excess of about 10 pct usually imparted refractoriness to porcelain enamels. Present-day one-coat porcelain enamels must combine high gloss and opacity with freedom from surface defects. Methods of beneficiating the over-spray,

Jan 1, 1948

THE. extraordinary volume of work done in this period, and the multiplicity of subject matter, make a year-by-year historical account undesirable, if the account is not to be an assembly of unrelated fragments. We shall, instead, undertake to narrate the development in this period of each of the branches of the subject separately, hoping that their interrelations will be self-evident. There is a certain arbitrariness in the selection of subject matter in the following sections. The development of important engineering alloys-for example, high-speed steel-is disregarded, for it is the primary purpose of this account to relate the advances in ideas, the growth of the science of metals; other historical accounts relate these parallel advances. Nor are advances in techniques stressed, though occasionally the most important are noted; nor is the progress described in allied fields such as welding, cutting, etc.; for though these developments have very frequently made possible the advances herein related, they are far too numerous to recount in anything short of a ponderous volume. There is a more serious arbitrariness, however; it is not an easy matter to draw the boundaries of physical metallurgy, and some contiguous subjects have been omitted that perhaps should have been included, such as, for example, corrosion, gases in metals, the magnetic behavior of metals and alloys, and certain other fields in the physics of metals. REACTIONS IN ALLOYS--DIFFUSION Many of the reactions occurring in alloys proceed by the operation of the process of diffusion in the solid state: the annealing of mixed powders to form alloys, the homogenization of castings or forgings, the freezing of alloys, the treatment of clad metals, the loss

Jan 1, 1948

By P. G. Beckett

THE problem of handling the large quantities of water encountered in the Old Dominion mine presents many features of interest. In the present paper are discussed the probable sources of water, the pumping equipment, the increased flow into the mine in the early part of 1915, culminating in the flooding of the 18th and 16th levels in March of that year, and the difficulties that were met with during the high-water period. I. PRELIMINARY The Old Dominion mine, situated 1 mile north of the town of Globe, Ariz., has long been one of the prominent copper producers of the State, and until the opening up of the copper schist deposits in the neighboring mines of Miami, was responsible for the greater part of the copper output from the Globe district. As the gradual exhaustion of its orebodies near the surface led to the downward development of the mine, more water was encountered in the western portions directly underlying the dacite formation until the drainage problem became a serious factor in the operation of the mine and in the economical extraction of the ore. A heavy inrush of water on the 10th level of the mine in 1906, preceded by still earlier water difficulties, rendered imperative the immediate installation of a pumping equipment capable of handling large flows of water. While the Old Dominion has been recognized as a wet mine since its early clays and one in which the complete control of the water situation was of paramount importance in the development of the lower levels, it is chiefly in the last nine years, since the installation of the increased pumping equipment, that the mine has developed and handled large quantities of water.

Jan 4, 1916

HAVING already shown you the methods of making the moulds for casting and how they are to be prepared so that they may receive the melted metals well, it is now necessary, in order to complete the casting with perfection, that I show you not only the operations and instruments by which metals are softened, but also how metals can be made as liquid and fluid as water so they may easily enter into all the hollows of the moulds that you have made. Of these, besides the fire which is the prime agent, there is a very powerful furnace, which is called a reverberator.* I believe this is chosen not only for convenience but also because it is necessary in large casts. This is made of baked bricks, or of crude ones if desired or of suitable fire-resistant stones. Although all masters have the same objective, each one proceeds to make this kind of furnace according to his own ideas so that it can be said that there are almost as many different shapes of such furnaces as there are masters. This can be seen in the place that contains the metal, which is of such a shape that the force of the fire may operate better. Thus some masters are called good who, seeing no farther than what has been shown them, make them circular like a bread oven. Some others make them oval across the fire en- trance, while others extend them lengthwise. Also, there are some who make a single outlet for the flames, some two, and some three. Some make the entrance for the fire high and narrow and others, wide and low. The same is true of the place where the flames are generated, which is called the firebox. Some put the wood in from the side, some lengthwise in the same direction as the entrance for the flames, and some from above by means of a little hole. Also, one makes the vault low, and another makes it high. And while one puts an entrance for air underneath so that the

Jan 1, 1942

By Frederic E. Carter

The gold, silver, copper alloys have been the subject of several fairly complete investigations by Janecke, Sterner-Rainer&apos; and others, and indeed it would seem as if almost too much labor had been expended on them when one thinks of the numerous other ternary alloys calling for more light; however, the combinations of the three metals are actually so widely used in jewelry that they merit perhaps the work done on them. There are a few properties of importance and interest not treated by the authors mentioned which the writer investigated some little time ago, and therefore he has ventured to put on record the results of some of his tests made at that time. He has chosen, as being the two series of most importance to the jeweler, only the 14 and 18-kt. golds, so the subjcct is by no means so inclusive as that previously treated. As statecl, this paper is merely a record of tests made in a practical manner on two itucbful series of alloys, and is not at all a critical study of their properties. 14-Karat Alloys These alloys are important because they arc the most generally II,<(S(I in 14-kt, jewelry; by changing thc proportions of silvcbr and copper Iliero are obtained all shades of color from the green of the alloy contiainng gold and silver but no copper, to the red of the alloy containing gold ;,, copper but no silver. Many 14-kt. gold alloys are made with the sdditjon of zinc to the three metals mentioned here; the added lnetnl does not appreciably alter the color of the alloy nor has it, in general, much effect on the working properties; it may, however, prove useful as ynrt of thc zinc added may act as a deoxidizer and render the alloy free of ga,s. 11, iy not a necessary addition because with proper precautiolls :111 I lie 14-At. gold alloys containing only silver and copper in :tcltlitiotl to the gold ran be made free of gas and capable of being cold rolled without craci The alloys in which approximately equal quuntiticrs of silver ami

By Maurice Ewing

THE purpose of this paper is to present the results of the application of the earth-resistivity method of subsurface investigation to the problem of locating seams of anthracite coal beneath a mantle of soil and subsoil. Details are given of the successful use of this method in locating the outcrops of anthracite seams in actual prospecting. The presence of the outcrop of an anthracite seam is indicated at points where electrical resistivity tests showed relatively low readings. The reason for, this is that in some localities the resistivity of anthracite was found to be about 0.0001 megohm-cm. compared to 1 to 200 megohm-cm. for shales and sandstones. For two reasons it is believed that the data sum-marized in this paper should be of particular interest. In the first place, most of the interpretations of the resistivity survey have been checked by subsequent drilling and some by the removal of the overburden and the exposing of the anthracite seams. It is infrequent that the oppor-tunity for checking results so thoroughly is given. In the second place, the fact that recent commentators 1.2.1 on the application of geophysical methods to mining have concluded that direct prospecting for anthracite and other types of coal is not promising makes the good results obtained more significant. So far as the authors can learn, the only previous experiment with electrical methods in the Pennsylvania anthracite field was one made by Sherwin F. Kelly in 1922, when he used the self-potential method at Wilkes-Barre4. The profile he made does not show a very marked correlation with the geologic cross section. Kelly points out that stray currents from electric motors in the mines undoubtedly affected his results, but the experience of the present authors with stray currents from mining machinery suggests the possibility that the potentials measured by Kelly were due almost entirely to this effect.

Jan 1, 1936

Lester Guttman (General Electric Research Lab-boratory)—Seybolt has measured the thermodynamic activity of silicon in dilute solution in a iron. The anomaly which appears at 800 °C in the approximate range 1 to 6 wt pct Si is most naturally attributed, as Seybolt has done, to the existence of a region of

Jan 1, 1960

By Zay Jeffries

THE history of the development of our great iron and steel industry has been recorded in many publications, not the least important of which are the TRANSACTIONS of the American Institute of Mining and Metallurgical Engineers. During the life of the Institute, of less than 60 years, the annual production of pig iron in the United States has increased more than 23 times. Such a rate of growth may seem small when compared with that of the automotive industry, which has increased 100 times in the last 20 years, or when compared with the growth of other industries of recent birth. The comparison appears less unfavorable, however, when the fact is taken into consideration that the iron and steel industry has existed on the earth in some form for thousands of years. The trade journals, the Department of Commerce and technical societies keep us currently informed concerning technical and corporate developments and the statistics of the American iron and steel industry. Merely to describe the high spots of the industry as it exists today would require a book of no small size. It involves the utilization of about 900,000 people, the payment of $1,400,000,000 in annual wages and salaries, the-investment of $14,000,000,000, the mining annually of 70,000,000 tons of iron ore, 15,000,000 tons of limestone, and 120,000,000 tons of coal. It results in the production of 40,000,000 long tons of pig iron and 50,000,000 long tons of steel ingot. In addition, the industry includes ownership and operation of railroads and steamship lines, the production of cement, timber, coke, gas, by-products, and many other activities. The leading part played by the iron and steel industry in promoting the confidence of the public in corporations and corporate management is well known. The industry has also provided worthy examples of vertical integration and mass production. The social activities within the industry have been no small factor in promoting the fuller development and greater happiness of the American working man-and his family. In this connection I advise reading a paper by Theodore W. Robinson,1 which

Jan 1, 1930