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By S. Epstein

THE new low-alloy high-strength steels are obviously here to stay. With 75 per cent higher yield strength and 50 per cent higher tensile strength than plain carbon structural steel, they permit 20 to 40 per cent weight savings and 10 per cent or more increase in pay load in the con-struction of railroad cars, buses, trucks, and a great variety of material-handling equipment. Their cost is low enough so that the extra cost of the new lighter construction over that with carbon steel offers an attrac-tive self-liquidating investment; in some instances new construction with these low-alloy steels may even be as cheap as with plain carbon steel. A considerable and rapidly growing demand for the low-alloy steels has already sprung up. The many steel compositions that have appeared on the market lately 18,27,28,29,30 to meet this demand would seem to indicate that no single composition is uniquely fitted for the purpose. However, no doubt some compositions are more suitable than others. The purpose of this study was, therefore, to compare the effects of the various alloying elements that might be used in the low-alloy steels in order to choose the metallurgically most logical composition, paying due regard, of course, to the economic aspects involved.

Jan 1, 1936

By R. S. Dean

The function of the Metallurgical Division is to conduct investigations relating to the treatment of mineral products from the state in which they are mined to the refined metal or other unfabricated product. These investigations include scientific and practical studies of ore dressing, covering the crushing and grinding of ores, separation by gravity, flotation, and magnetic methods; the hydrometallurgical treatment of ores, including cyanidation and amalgamation of the precious metals; the smelting and refining of copper, lead, and zinc, as well as the rare metals; and steel-melting practices from the raw ore to the finished steel. The object of this work is to conserve natural resources and eliminate waste by furnishing information on current methods of metallurgical practice, making fundamental studies of metallurgical processes, and developing new processes to the point of demonstrating their practicability. The Division is made up of sections devoted to the several phases of this work, each section being beaded by an investigator capable of supervising his particular work. The work is carried on at the experiment stations and field offices or in the field, whichever seems test suited for the work in hand. The following projects should be mentioned as particularly outstanding among those consummated successfully during the year: 1. Application of the type of chemicals known in the textile industry as wetting-out agents to flotation and agglomeration of ores, particulary soluble salts such as sodium and potassium chloride which must be treated in saturated brine. 2. Demonstration of a linear relation between surface and coercive force in magnetic minerals and its application to magnetic separation and to the determination of grinding efficiencies and other metallurgical data which require surface determination at very fine sizes. 3. Pilot-plant demonstration of the practicability of the reduction of iron ore by natural gas and conversion of this direct iron into steel by direct melting and by forging and rolling before melting. The structure and properties of the iron so produced were studied in detail. This report covers the fiscal year July 1, 1934, to June 30, 193b.

Jan 1, 1936

By John T. Thorndyke

MOST important of the naturalcalcium silicates is the meta¬silicate, CaSi03, known as wollastonite, after W. H. Wollaston. A large deposit of this mineral was dis¬covered some seven years ago near Code Siding, Rademacher mining dis¬trict, Kern County, Calif., the deposit being some 7500 ft. long and of an average width of 300 ft. It consists of a series of small domes striking north¬erly and southerly and with a dip of 81 ° to the south. This deposit was opened up by a series of small quarries showing a potential tonnage of 12,000,¬000 tons, allowing of cheap mining and transportation, the Southern Pa¬cific R.R. spur track being one mile north of the workings. Numerous sam¬ples taken from different points on the deposit, tested by Mr. Brinker, of the California Testing Laboratories, Los Angeles, showed an average as fol¬lows: Per Cent Silica (SiO2) 47.12 Lime (CaO) 41.72 Magnesia (MgO) 2.72 Alkalies (R,0) Trace Iron (Fe.,O,) 1.60 whereas the theoretical composition of of wollastonite, as given by William Shirley Bayley, is as follows: Silica 51.75 Lime 45.25 The tonnage and purity of this de¬posit led to investigations into its com¬mercial development. Early work es¬tablished the fact that wollastonite was ideal for the manufacture of a tough, almost unbreakable, glass similar to Pyrex. It also established the fact that wollastonite was particularly adapted for use in the manufacture of mineral wool, towards which further research was then directed. Briefly, the prin¬cipal advantages were the substantially unvarying chemical composition of the naturally occurring mineral and its characteristic of being relatively flexi¬ble and highly resilient when fused into a glass. A mineral wool produced therefrom is thus not only of highly uniform composition and color but is most desirable because of the high mechanical strength and length of the individual fibers constituting the wool. It is well known that mineral wool may be prepared by melting a suitable charge of raw material and then intro¬ducing a stream of a suitable fluid, such as air or steam, into a stream of the molten raw material. By this means the molten material is blown into threads or fibers, which are collected in a suitable chamber similar to a tun¬nel, from which they are removed from time to time or continuously. Com¬mercial manufacture of mineral wool has been carried on for only about 50 years, but volcanoes, specifically Kilauea in the Hawaiian Islands, have

Jan 1, 1936

By J. W. Craig

THERE are, broadly speaking, three classes of refractories: acid, basic, and neutral. Fireclay, diaspore, silica, and the sillimanite group of minerals are included in the acid class, which for the most part are not very resistant to basic slags. The neutra! class includes chrome, graphite, and silicon carbide, while most important in the basic class are magnesite and dolomite. Although chrome is a neutral refractory, it has no sharp distinction from magnesitic refractoriness. The two are mineralogically (1) and chemically related, and there is available on the market a complete range of brick from straight chrome to straight magnesite. In many indus trial applications, one. type may be replaced by another. The present paper is confined entirely to such refractories. The following types of basic and neutra! brick, each sold under sorne special trade name, are available for use in Canada: (1) Burned chrome from crude ores (2) Burned chrome from treated ores (3) Chemically bonded (unburned) chrome-magnesite ( 4) Burned chrome-magnesite (5) Chemically bonded ( unburned) magnesite-chrome (6) Chemically bonded (unburned) high-iron magnesite (7) Burned high-iron magnesite (Regular) (8) Burned low-iron magnesite (9) Burned olivine-magnesite (10) Burned magnesitic dolomite-chrome (Magnecon) (11) Chemically bonded magnesitic dolomite-chrome (Magmecom) (12) Dolomitic brick

Jan 1, 1936

By The Staff

FOR forty years cyanide men have been intensively engaged on the treatment of sulpho-telluride ores. So far as we know, the processes used today were-with the important exception of the concentration plus high-lime process at the Victor mill (1915)-in use, or had been tried, in the earl y years of the century. Roasting, bromocyanide, ordinary cyanide, table and vanner concentration, floating and treating the concentrate, roasting con-centrates prior to treatment, etc., all were used at Kalgoorlie in 1904 or earlier. Flotation, followed by shipment of the concentrate to the Golden Cycle mill, was the practice at the Vindicator mine, Cripple Creek, for some years prior to 1917. Similar practice was employed in the Portland Independence mill at Victor, Colorado, and was lacer superseded by the table concentration, high-lime cyanide treatment of rails of the older Portland Victor mill. During all this time, an immense amount of research was being clone on these ores by the staffs of numberless companies. Conclusions were drawn and mills built. But if the results of one per cent of this research were ever published in sufficient detail for intelligent use by others, the Lake Shore staff has been unable to discover them, or does not recall having clone so. Government laboratories-as for instance chose of the Mines Branch, Ottawa, in or about 1927-have touched upon certain methods in their publications, but they simply have not had the time to finish the job. The paper by W. E. Johnston, Tellurides-Problem or Alibi? (E. & M.]., Aug., 1933), aroused wide interest and comment. It published conclusions, some right and some wrong, and gave the evidence adduced by the author i:n support thereof. Conclusions published without supporting evidence are to most of us worse than no conclusions at all. We suggest chat, if even one-tenth of the operators had published full, detailed results of their laboratory work, ad vance in the treatment of sulpho-telluride ores would have been very much accelerated. Therefore, we venture to inflict upon the Institute a compendium of the results of laboratory work performed during the past few years at the Lake Shore mill. It is really a summary of the more interesting results to date, prepared by the mill staff for their own use and benefit. But we hope chat the discussion under any heading is so detailed chat it will be intelligible to anyone interested in that phase of the subject.

Jan 1, 1936

By Chas. G. Maier

The absence of plants on the Pacific coast for the reduction of iron ores usually is attributed to the fuel situation there. Thus, the bulletin of the. State Division of Mines for 1933, entitled "California Mineral Production," says: "There are considerable deposits of iron ore known in California, notably in Shasta, Mad era, Placer, Riverside, San Bernardino, and Los Angeles Counties, but production has so far been limited for lack of an economic supply of coking coal." It has been estimated that the six major steel plants of the Pacific coast have an annual ingot capacity of 600,000 tons. The present need for tin plate averages 300,000 tons yearly for California alone, of which some 12 percent is manufactured locally. If the consump¬tion of other iron and steel products in 1929 may be taken as an approximate, estimate of the normal requirement for such products, it may be estimated further that, 65,000 to 75,000 tons each of cast-iron pipe and steel reinforcing bars and 300,000 to 400,000 tons of structural shapes and plates will be required annually in California.

Jan 1, 1936

By Chas. F. Jackson

This bulletin is one of a series of Bureau of Mines reports dealing with mining methods, practices, and costs. A study of this subject was undertaken by the Bureau in cooperation with a large number of mining companies in 1928. This study continued for 5 years, during which engineers of the Mining Division of the Bureau visited most of the larger mines and many smaller ones in the United States, as well as several mines in Canada and Mexico. As a result of this study, 75 reports dealing with underground mining methods and costs at different mines were published as information circulars. Circulars also were issued on 6 open-pit mines and 2 gold-dredging operations. These circulars were written by the managers, superintendents, and engineers in charge of the operations, in some instances in collaboration with Bureau engineers. They were prepared according to a standard outline drawn up by the Bureau to obtain uniformity in textual treatment and in the arrangement and basis of setting up cost and operating data.

Jan 1, 1936

By H. H. Power

THE PETROLEUM DIVISION of the A.I.M.E. continued with its diversified activities during 1.935. Sessions at the New York meeting in February were devoted to production engineering, domestic and foreign oil production, and petroleum economics. The symposiums on domestic and foreign production proved their increased usefulness. The data accumulated for 1935 were added to those published during prior years in "Petroleum Development and Technology." A joint session on the use of metals in the petroleum industry was held by the Institute of Metals, Iron and Steel, and Petroleum Divisions. W. S. Farish, chairman of the board of the Standard Oil Co. (N. J.), was the principal speaker at the annual dinner. The October meeting, held in Hous¬ton, was characterized by an excellent program and large attendance. Four sessions were devoted to problems in estimating reserves, reservoir energy, properties of drilling muds, electrical logging, water flooding, and other subsurface studies. Foreign representatives of the Anglo-Persian Oil Co. presented a paper on surface tension and specific gravity of crude oil under reservoir conditions. The address by President Buehler, the dinner at San Jacinto Inn, a trip to various lo

Jan 1, 1936

By Robert D. Lonqyear

SOMEWHAT biased by pride in twentieth century achievements, most of us mining engineers and diamond-drill operators look upon core drilling as a relatively modern practice. The invention of the diamond drill is generally ascribed to Rudolf Leschot, who made use of diamonds in 1846 in drilling blast holes in the Mont Cenis tunnel in Switzerland. In vain we search Agricola and other early writers on mining for signs of diamond drilling. We have, therefore, concluded that it was unknown until the middle of the last century. The trouble with this conclusion, as most prospectors will tell us, is that we "don't dig deep enough"; for it now appears that the archeologists have been putting one over on us for the last fifty years.

Jan 1, 1936

By John A. Gann

THE Iron and Steel Division has shared in the general increased activity of the industry. The fall meeting at Chicago was not only well attended but particularly characterized by the virility and scope of the discussions at the various sessions. The program for the February meeting indicates a similar interest in technological developments. The Blast-Furnace Committee continues to have the hearty support of the industry with discussions of such a nature as to be of real help to the operator as well ass the technologist. The work of the Open-Hearth Committee continues to be outstanding, with ever increasing attendance and ever mounting interest in the meetings. Formation of a conference on the physical chemistry of steelmaking has given those interested in this phase of work an organization allowing the same

Jan 1, 1936

By Frank G. Breyer

THE .following developments in the zinc field during 1935 are listed in the order of their importance. Each will he amplified in later paragraphs. In the field o f Metallic Zinc: (1) Construction of further continuous vertical retort smelting capacity in the United States and Germany. (2) Expansion of fractional distillation capacity in the United States. (3) Great expansion in the zinc-base die-casting industry in the United States and abroad. (4) Wide acceptance of heavy galvanizing by the steel industry. (5) Construction of the first commercial wire electroplating plant for putting on heavy coats of pure zinc. (6) Firm establishment and appreciable expansion of the practice of using zinc dust as a reducing agent in the organic chemical industry.

Jan 1, 1936

By E. W. Pehrson, J. W. Furness

NONMETALLIC MINERALS, exclusive of fuels, may be divided into three groups: Building materials, fertilizer minerals, and miscellaneous minerals. Building materials, such as sand, gravel, slone, lime, and the ingredients of cement and clay products, occur widely in nature and are thus available near consuming centers at relatively low prices. Cost of transportation over great distances deters any' substantial movement in world trade. On the other hand, fertilizer minerals, such as phosphate rock, potash, nitrates, sulfur, and pyrite, and the miscellaneous nonmetallic minerals, such as long-fiber asbestos, mica, graphite, fluorspar, and china clay, do not have such widespread occurrence and consequently contribute the major part of the world's commerce in such minerals. The U. S. Bureau of Mines has prepared charts showing the inter-

Jan 1, 1936

By Paul M. Tyler

MARKETWISE the year 1935 was rather a good one for most of the rare and minor metals; as a class they climbed out of the depression much faster than the common metals. The diamond market, too, was better than it had been for years, attributable only in part to investment buying, as there was a genuine pick-up in consumer demand. Wars and rumors of war tended to speed up purchases of certain metals, but consumption for peaceful purposes was the principal factor. Significant was the important role played by new industrial uses. New discoveries during the year were disappointingly few, considering the broad extent of this research frontier. Scientific developments were far from being at a stand-still, of course, but the dominant note was the cashing in on research consummated in former years. With even a moderate upturn in general business a surprising number of laboratory ideas donned overalls and found jobs in industry.

Jan 1, 1936

By E. W. Pehrson, J. W. Furness

THE five charts presented here- with are part of an original group prepared by the U. S. Bureau of Mines showing the international trade in the principal metals and metallic ores. Charts 011 anti- mony, chromite, copper, lead, manganese, mercury, nickel, tin, tungsten, and zinc were published in the February, 1936, issue of the Engineering and Mining Journal. Those shown here include bauxite, aluminum, iron ore, pig iron, and the platinum-group metals.

Jan 1, 1936

By Thomas T. Read

IN reviewing the field of mineral industry education last year reference was made to recent assertions, mostly emanating from sources not in a position to know the facts, that mining engineers as a class are disappearing. Attention might also then have been called to a statement that appeared in Engineering News, August 11, 1892 (p. 130), ". . . the great absolute decline in number of mining graduates, which last amounts almost to a complete abandonment of mining engineering as a distinct branch of study." Evidently we outrank opera stars in the number of farewell appearances we are able to make; 43

Jan 1, 1936

By G. R. Hopkins

"Summary An apparent decline in fuel efficiency at refineries, which first became came evident in 1930 and continued through 1933, was checked in 1933 when the average amount of heat needed to refine a barrel of crude oil amounted to 660,000 B.t.u. This compares with an average requirement of 692,000 B.t.u. In 1932 and with a low of 639,000 B.t.u. in 1929. (See fig. 1.) The improvement in fuel economy in 1933 probably was closely related to the increase of 5 per cent in crude runs to stills. As much of the fuel burned at refineries is utilized for purposes other than under crude-oil stills and in relatively stable amounts, it is evident that a material increase in crude runs will usually reflected in a decrease in average fuel requirements. Another factor which has influences fuel economy at refineries in the past is the trend in cracking, a refining process requiring more than the average expenditure of heat. In 1933 production of gasoline by cracking increased slightly, but no appreciable rise in heat requirements resulted as an equivalent amount of fuel was saved in improved technique, particularly in the field of heat exchange.Since the beginning of the refining industry, the transition in fuels has been from solid to liquid to gaseous; in other words, the leadership was first held by coal, then passed to oil, and is now held by gas. In 1933, 54.7 percent of the total heat units generated came from gas, 39.0 percent from oil (including acid sludge), and 6.3 percent from coal and coke. The principal change in the relative importance of the various refinery fuels in recent years has been the rapid growth in consumption of refinery or still gas at the expense of all the other common fuels. Still gas owes its ascendency to its cheapness and availability, and probably it would have become the primary refinery fuel years ago if recovery methods had been perfected. The relative importance of coal showed a small increase in 1933, the first gain recorded since these surveys were inaugurated in 1925. The increase in use of coal was undoubtedly due to increased operations at plants using it,"

Feb 1, 1935

By R. S. Dean

"Applied Mineral Physics, by R. S. Dean.- This is an introduction to the seven papers that follow. It discusses the practical aspects of mineral physics and outlines the theo¬retical viewpoint underlying the investigations reported herein.Explosive Shattering as a Possible Economical Method of Ore Presentation By John Gross and C. E. Wood. - It is shown that explosion shattering by impact is favored by large charges and by low ratio of water to charge. For 400-gram charges of dolomite crushed through 48 mesh the steam costs are less than 5 cents per ton of dolomite obtained. This is within the range of present steam costs for ball-milling dolomite.Electrical Properties of Minersl Aggergates I. Natural and Artificial Aggregates Crystallized Lead Sulphide By R.S. Dean and John Koster - This paper deals with the electrical properties of natural and synthetic galena. It is shown that massive crystalline galena has a normal positive temperature coefficient of resistance, whereas fine-grained steel galena has a negative temperature coefficient, the curve R v. T being exponential in form. That steel galena behaves somewhat like a leaky condenser is indicated by ballistic and alternating-current bridge measurements. In determining the cause of the erratic results of alternating-current resistance measurements it was observed that the measured re¬sistance was a function of the current through the specimen. The direct-current resistance was found to be proportional to the square of a superimposed radio-frequency current and independent of the frequency.The influence of grain size or the amount of metallic interface on the voltage-current characteristics at various temperatures on synthetic galena pastilles was studied. It is proved that the volts v. amperes curves are linear for all sizes and temperatures, that they have an intercept which is apparently a linear function of the temperature, and that their slopes are exponential functions of the temperature and give rise to a negative temperature coefficient of resistance.Apparatus for determing the Magnetic Constants of Mineral Powders by V,H, Gottschalk,and C. W. Davis.- A modified isthmus permeameter having a spark-suppressed primary and a multiplier in the secondary circuit to regulate the effect of capsules functioning as a twin isthmus is used to obtain quantitative data and normal induction and hystersis curves from small amounts of powdered material at fields surpassing 3.000 oersteds. Data and curves are given to demonstrate the calibration of the apparatus and the reproducibility of its results. Applications and limitations of the apparatus are noted.Magnetization Curves for Magnetite Poeders by V. H. Gottschalk and F. S. Wartman.- This paper gives measurements on four lots of purified and analyzed magnetites in mixed fractions with especial reference to the variation of permeability with grain size and with dilution by an inert material."

Feb 1, 1935

By Bernard N. Moore

At present the demands of the United States for strorltium are met by imports from Germany, England and Canada, which vary considerably in proportions of ore and finished salts, in tonnage and in value. Statistics for the period 1926-1932 are given in Table 1. Domestic deposits arc known in many states, but the larger and purer ones are in the West, particularly in the desert region of southeastern California and western Arizona. These deposits are large enough to command interest, particularly in consideration of future cheap power at the Boulder Dam. The deposits described in this paper were examined during an investigation of the mineral resources of the Boulder Dam region by the United States Geological Survey for the United States Bureau of Reclamation in the spring of 1934. Mr. D. F. Hewett, who had general charge of the investigation, Mr. W. T. Schaller and Mr. M. I. Goldman contributed many helpful suggestions. Mr. N. H. Harshman assisted efficiently during the field work. Celestite Deposits The celestite deposits described in this paper are of sedimentary origin and Tertiary age. They are widely scattered, as shown on Fig. 1,

Jan 1, 1935

By C. V. Brennan

This paper, describing the various mining methods and practices at Britannia mines, Britannia Beach, British Columbia, is one of a series covering mining practices, methods, and costs in the mining districts of the United States and Canada. The Britannia property has been operated continuously for 30 years, and in that time many diverse methods have been used in exploiting the various types of orebodies worked. Under normal conditions mining methods include surface gloryholes, shrinkage stoping, shrinkage with powder drifts for primary breaking, horizontal cut-and-fill, horizontal and inclined square-setting, and timbered and open rills, the three latter systems being combined with close filling. The Britannia method of mining, a large-scale retreating shrinkage system usually combined with powder drifts for primary breaking, has been developed and applied here very successfully. Each block of ground as developed is studied as a separate problem, and the mining method, or combination of methods best adapted to the work in hand is applied thereto. Operating at, capacity, the series of mines produces 7,000 tons of ore per day.

Jan 1, 1935

By Selwyn G. Blaylock

There is no more important problem today than industrial relationship, and probably none that is receiving more thought. But in these days of Epie and Utopia, one has to be rather careful in speaking on this subject. Consequently, for fear that my plea for taking the working man into the family might be misconstrued, by some, as a step towards communism or socialism, I would like to say at the outset that I believe that, so long as we have human individualism, human ambitions, human hopes and fears, straight socialism is as far off as the Millennium. The same applies to communism, which only differs from socialism in that the communist realizes that his ideals can only be attained by massacring millions and destroying all that we hold sacred. Each still looks to Russia for inspiration and guidance, totally disregarding the Soviet swing-back to individual contract work and differential wage scales. They seem to be oblivious of the tyranny and repression in the present Russian system, and get very restless when reminded of it. In spite of the fact that the standard of living in civilized countries has improved tremendously and is still improving, we find that, every seven or eight years, production in many lines has outstripped consumption, and we have had panics or depressions of greater or less magnitude, accompanied by extensive unemployment. It is evident to every thinking person that there must be no little inefficiency in the control of industry. For four long years, governments and industrialists have striven to find the key to solve the present problem. Many countries are getting back to a position approaching normal-Canada probably more so than most. None, however, can feel assured that they have actually cured the situation. All kinds of schemes have been developed; tariff barriers have sprung up over-night where none existed before; currencies have been inflated to gain added security in the home markets and to try to gain advantage in export trade; and each country watches the movements of the others with fear and mistrust. I am not prepared to formulate a full solution of our troubles, but I hope to be able to demonstrate the feasibility and wisdom of the type of industrial relationship I advocate, and also that it may be a large, and possibly an essential, step towards the solution of our difficulties.

Jan 1, 1935