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By Wilbert McBride

Two Alco 3 ½ -ton motor trucks were used by Young Bros. while operating at the Mammoth Collins mine at Shultz, Ariz. One was equipped with an oil tank holding 1,075 gal. and was used for the transportation of "tops." The, other was fitted with a stake body and used to carry machinery, wood, rails, pipe and all classes of miscellaneous supplies. The bodies were made of oak with maple flooring and were attached to the frame of the chassis by U-bolts, to avoid drilling the main members of the frame. Most of the hauling was done from Tucson, a distance of 47;2 miles. During the first. 3 months, part of the road was in very bad condition and the tire cost was excessive. After this part was repaired the road was in fair condition, but never good. There were no excessive grades or bad sand, but wagon ruts, too narrow for the truck wheels and of a different gage, caused heavy tire loss; while chuck holes, sharp curves and stones, both imbedded and loose, were objectionable features. During wet weather the trucks could not get sufficient traction to climb some of the hills and were likely to stick in the mud in certain places, so that no attempt was made to run them unless they were on the road when the rain started. This lost time amounted to about 5 per cent. of the total, but, whenever possible, it was utilized in making minor repairs. The price of gasoline, was from 17 to 21 c. per gal. Rubber tires were used throughout. Drivers were paid $4.50 to $5 per shift, and a return trip to Tucson was counted as two shifts even when made in one day. Drivers were provided with a room in Tucson and were paid for all time lost due to causes beyond their control. Trucks were loaded one way only.

Jan 7, 1916

By Edwin Ludlow

ONE of the most unusual features in connection with the strike of the union coal miners in the bituminous fields, now in its sixth week, is that the public interest seems to have completely died out. There is nothing on the front page and very little on any other page of the daily newspapers in connection with the strike. The United Mine Workers' officials must be rather disappointed to find that the only way in which they are being featured in the papers at present is in the reports of the trial for treason that is going on in Charlestown, West Va., against the local leaders of that organization for their responsibility in connection with the attack of the miners' army last summer against the non-union mines of Logan and Mingo Counties. Recent reports state that there are 13,000 cars of coal standing on the sidings at union mines for which no billing has yet been found. The output of the non-union mines has been gradually increasing but has never reached the maximum that they are capable of producing, owing to their inability to obtain enough orders to make it possible to run full operating time. The, present output is estimated at, 4,500,000 tons a week. It is possible, with a full car supply and full demand, to bring this output up to approximately 6,000,000 tons per week, and it is very doubtful whether, at this season of the year when probably there is less consumption of coal than, at any other season, the requirements of the country are greater than the 6,000,000 tons which the non-union mines are capable of producing. It would appear, therefore, that there is no immediate prospect of any settlement of the bituminous strike, and there is certainly no reason why the operators of the union mines should show any anxiety to begin operations as long as they have unbilled coal standing on their sidings.

Jan 6, 1922

By P. D. Wilson

The genesis of some orebodies has been explained by the mingling and chemical interaction of water solutions of different compositions and the consequent precipitation of the mineral load of one or both solutions at their confluence. While this process can be proved in the laboratory, rarely can a positive demonstration be found in nature, for the conditions at the time an ore deposit is being worked are usually entircly differcnt from those that existed when the orebody was formed. For this reason, the present deposition of copper carbonate in the southern end of the Briggs mine of the Calumet and Arizona Mining Co. near Bisbce, Ariz., is of great interest. The developed orebodies in the Calumet and Arizona mines are roughly confined to two broad parallel zones separated at the north by a wedge of Copper Queen ground and at the south by an undeveloped block of Calumet and Arizona ground about 2000 ft. (610 m.) wide. The more westerly zone includes the Irish Mag, Oliver, P. and D., and Cole mines, none of which has been operated since 1919. Much of the water from this division is carried from the 1400-ft., or bottom, level at the southern end of the Cole mine in a long water drift through the undeveloped block to the 1300-ft. level of the Briggs mine at the southern end of the more easterly zone. Most of this water comes originally from outlying areas in the P. and D. mine, passing through parts of the lower. levels of the Cole mine, which are heavily mineralized with iron and copper sulfides. This sulfide zone has been opened up and slowly oxidizing for years. Originally a pure, potable water, the analyses of which are shown under A- in Tables 1 and 2, on its way through the mineralized area in the Cole mine it gathers copper, calcium, magnesium, iron, and aluminum sulfates, a load of dissolved mineral salts almost four times as great as that which it formerly carried; analyses B

Jan 1, 1923

By B. J. Yamada, D. W. Fuerstenau

Long-chained neutral molecules (decyl alcohol) increase the flotation of corundum with sodium dodecylsulfate and trimethyldodecylammonium chloride as collectors. This phenomenon is postulated to result from coadsorption of the neutral molecules with the collector ions. Flotation and streaming potential experiments have shown that sodium laurate is an effective collector for corundum at more dilute concentrations than sodium dodecylsulfate or sulfonate.1>2 It has been postulated that this phenomenon results from the adsorption of both laurate ions and lauric acid molecules, whereas sodium dodecylsulfate can be adsorbed only as dodecylsulfate ions, since this collector does not hydrolyze under flotation conditions. Similar effects have been observed in alkaline solutions with dodecylammonium chloride and trimethyldodecylammonium chloride as collectors.' If in- creased flotation occurs with the collectors which hydrolyze because of adsorption of the neutral molecules, purposeful addition of long-chained molecules should increase the flotation rate of minerals with such collectors as sodium dodecylsulfate or trimethyldodecylammonium chloride because these long-chained molecules should coadsorb with the collector ions. The effect of neutral molecules on flotation in these cases must depend on an adsorption mechanism which differs from that proposed by Cook for the adsorption of xanthic acid molecules by galena. For neutral molecules to function as collectors in the flotation of insoluble oxide minerals, adsorption of organic ions must first occur to provide a means of anchoring the fatty acid or amine molecules. Without adsorption of collector ions, flotation does not occur even in the presence of large quantities of neutral molecules, as is indicated by the cessation of flotation at low pH values with soaps as collectors or at high pH values with primary amine salts as collectors.' Neutral molecules, such as fatty acids, must be adsorbed through van der Waals attraction between the hydrocarbon chains of the adsorbed soap ions and the hydrocarbon chains of the fatty acid molecules. The mutual association of hydrocarbon chains results

Jan 1, 1962

By M. S. Azun

The authors' paper did not explain the facts and reasons why state companies are established and what their role is in international industrial mineral trading. Also. I do not agree with the conclusion implying that the main goal for state companies is to capitalize natural resources. Almost all state companies are founded by certain laws and their activities are arranged by state regulations. Their only aim is to operate mineral deposits for their people and to protect the rights of the people. Although some ore deposits, such as nonstrategic or small, may be exploited by privately owned companies, the state has the right to control the operation and production. Activities of state companies may or may not be widened because of the character of the deposits and the importance of the mineral market involved. For some countries, although governments may occasionally change hands, the policy of the mineral trading system is not affected by this change. There is no doubt that any government desires to make more earnings to increase GNP, when it is involved in operating and trading mines. It wants to produce and sell the finished products, instead of unprocessed ones, if possible. When it is known that some mineral deposits are relatively rare, such as Turkish boron deposits, the government can nationalize the mines to control production and affect the market. If there is an abundance of a certain mineral in the market, the government can cut production and set a floor price, such as Canadian potash. Also, when production of a specific mineral is unique, such as Turkish chromite, the price of such mineral may be set by correspondent government. One may add that if some governments with their state companies produce a certain mineral in a larger amount, they may decide to establish a cartel to protect their production and price. These are the facts followed by government-owned state companies and partially government-owned companies. The reason being charge of many deposits by the state companies is always the same: "protect" the mineral rights of the people.

Jan 1, 1985

By Nicholas T. Camicia

A career in the coal mining industry today offers students one of the most interesting and challenging opportunities available in the industrialized world. As reserves of other fossil fuels dwindle in face of the world's demand for energy, it has become apparent that coal, once the king of energy sources, must be relied upon again as the major fuel for powering industrial growth in developed and developing nations. Centuries of coal supplies lie beneath the earth's surface, assuring the world of a steady, plentiful supply of energy until science and technology can produce a way to harness and efficiently use renewable sources, such as solar. The need to increase our use of coal during the last two decades of the 20th century is reason enough to believe that the future growth of the coal industry is assured. A major impediment to that growth might be backward national public policies that could restrict the full utilization of our coal reserves. These policies could result from overregulation and a failure of the public to recognize that coal use, with proper techno- logical safeguards, is compatible with our society's environmental-quality objectives. Communication of this problem and its solution is a major undertaking of the coal industry in the 1980s. At the end of the 1970s, the American coal industry was producing approximately 635 Mt/a (700 million stpy) of coal. To meet the nation's projected energy needs by 1985, the annual tonnage must be doubled. A similar scenario is predicted for the rest of the world. Such growth in the modern international business world will require huge additional amounts of capital, equipment, and people who know how to wisely raise and apply the capital; use the equipment productively; and deal with the many community, public, and governmental problems such expansion will create. Whether a student's interest is in actual mining operations, business administration, engineering, finance, law, industrial relations, marketing

Jan 1, 1981

By Philip Wilson

THE genesis of some orebodies has been explained by the mingling and chemical interaction of water solutions of different compositions and the consequent precipitation of the mineral load of one or both solutions at their confluence. While this process can be proved in the laboratory, rarely can a positive demonstration be found in nature, for the conditions at the time an ore deposit is being worked are usually entirely different from those that existed when the orebody was formed. For this reason, the present deposition of copper carbonate in the southern end of the Briggs Mine of the Calumet and Arizona Mining Co. near Bisbee, Ariz., is of great interest. The developed orebodies in the Calumet and Arizona mines are roughly confined to two broad parallel zones separated at the north by a wedge of. Copper Queen ground and at the south by an undeveloped block of Calumet and Arizona ground about 2000 ft. (610 m.) wide. The more westerly zone includes the Irish Mag, Oliver, P. and D., and Cole mines, none of which have been operated since 1919. Much of the water from this division is carried from the 1400-ft., or bottom, level at the southern end of the Cole mine in a long water drift through the undeveloped block to the 1300-ft. level of the Briggs mine at the southern end of the more easterly zone.. Most of this water comes originally from outlying areas in the P. and D., mine, passing through parts of the lower levels of the Cole mine, which are heavily mineralized with iron and copper sulfides. This sulfide zone has been opened up and slowly oxidizing for years. Originally a pure, potable water, the analyses of which are shown under A in Tables 1 and 2, on its way through the mineralized area in the Cole mine it gathers copper, calcium, magnesium, iron, and aluminum sulfates, a load of dissolved mineral salts almost four times as great as that which it formerly carried; analyses B

Jan 7, 1922

By Nicholas T. Camicia

A career in the coal mining industry today offers students one of the most interesting and challenging opportunities available in the industrialized world. As reserves of other fossil fuels dwindle in face of the world's demand for energy, it has become apparent that coal, once the king of energy sources, must be relied upon again as the major fuel for powering industrial growth in developed and developing nations. Centuries of coal supplies lie beneath the earth's surface, assuring the world of a steady, plentiful supply of energy until science and technology can produce a way to harness and efficiently use renewable sources, such as solar. The need to increase our use of coal during the last two decades of the 20th century is reason enough to believe that the future growth of the coal industry is assured. A major impediment to that growth might be backward national public policies that could restrict the full utilization of our coal reserves. These policies could result from overregulation and a failure of the public to recognize that coal use, with proper techno- logical safeguards, is compatible with our society's environmental-quality objectives. Communication of this problem and its solution is a major undertaking of the coal industry in the 1980s. At the end of the 1970s7 the American coal industry was producing approximately 635 Mt/a (700 million stpy) of coal. To meet the nation's projected energy needs by 1985, the annual tonnage must be doubled. A similar scenario is predicted for the rest of the world. Such growth in the modern international business world will require huge additional amounts of capital, equipment, and people who know how to wisely raise and apply the capital; use the equipment productively; and deal with the many community, public, and governmental problems such expansion will create. Whether a student's interest is in actual mining operations, business administration, engineering, finance, law, industrial relations, marketing

Jan 1, 1981

The editorial expenses for the preparation of the manuscript of the second edition, as for the first, were provided by grants of the Engineering Foundation and the Open Hearth Steel Committee of the Iron and Steel Division, AIME ; the Seeley W. Mudd Memorial Fund again sponsored the publication of this volume. The companies and research or educational institutions with which the authors, reviewers, and editors are connected also contributed much to the writing and editing of this book through their generous donations of time and travel and office expenses. And finally, the authors and others have given countless hours of their own time with no recompense but the satisfaction of a job well done. In order to give credit to the companies or educational institutions which made it possible for the members of the Editorial Board to devote considerable time to the revision of this book, the names of these members and their affiliations are recorded here as follows : W. O. Philbrook, Carnegie Institute of Technology M. B. Bever, Massachusetts Institute of Technology H. B. Emerick, Jones and Laughlin Steel Corporation B. M. Larsen, United States Steel Company A number of individuals suggested desirable changes in the book before rewriting was started. Almost all manuscripts were gone over critically by reviewers, and the resulting criticisms led to the correction of errors and omissions and greatly contributed to the accuracy and completeness of the text. Other people have supplied additional data or illustrations or assisted in other ways. While some of these contributors must remain anonymous because they are not known to the Editors, the cooperation of the following individuals is gratefully acknowledged : R. D. Allen, Republic Steel Corporation, Chicago Isadore Amdur, Massachusetts Institute of Technology Mary Baeyertz, Armour Research Foundation S. P. Bahmer, Republic Steel Corporation, Massillon E. C. Bain and Associates, United States Steel Company, Pittsburgh C. W. Briggs, Steel Founders' Society of America H. W. Briske, Wisconsin Steel Works

Jan 1, 1964

By A. B. Kinzel

MUCH work has been done recently in an attempt to analyze the physicochemical mechanism involved in the production of steel by the open-hearth process. . This has resulted in reducing the process to a series of interrelated phenomena obeying the usual laws of mass action and diffusion. Of these, the reaction of the iron oxide and carbon in the molten steel is of most interest from a technical point of view as it con-stitutes the main action in the usual steelmaking processes. A. L. Feild1 has formulated a basic differential equation expressing the open-hearth reactions and Hefty has done considerable experimental work on the determination of a number of constants involved in the basic open-hearth reaction. In considering the application of the law of mass action. to the reaction FeO +C ?? CO +Fe, the iron will be taken as constant, as is the case in the open hearth and the carbon monoxide pressure will be assumed' constant at one atmosphere. From this xy = m at equilibrium, where x is the percentage weight of carbon, y percentage weight of iron oxide and m the weight-concentration equilibrium constant. While it is customary for physical chemists to express equilibrium constants in terms of molar concentrations, the constant is here expressed as the product of the percentage-weight concentrations for ease of comparison with the constants quoted by Herty and by Feild, and for more ready applicability to the open-hearth reactions. Herty and his associates have attempted to calculate the value of this constant from data on open-hearth heats. So many variables affect these results that an adequate calculation presents very great difficulties. A value of 4 X 10-2 was first arrived at, but this was later changed to 1.6 X 10-2. Feild, in order to illustrate the operation of the differential equation of the open hearth, has assumed a value considerably lower than Herty's, namely, 1.0 X 10-2, the largest value consistent with certain theoretical

Jan 1, 1929

By H. M. Merry

The graphic methods and records described in this article have been developed, with satisfactory results, for the use of executives of the Chino Copper Co., in Hurley, N. Mex. Particular attention is directed to the use of large wall-charts, the quick reference display of large charts, the scale notation of metallurgical charts shown in Pig. 3, and the inclusion of mesh extraction on screen analysis diagrams. To properly comprehend the operation and metallurgical results from a concentrating plant, a daily record of essential data is kept, usually involving the dry weight of ore milled or treated, dry weight of concentrate or metal produced, assay values of heading, assay values of tailing, assay values of concentrate, and percentage of extraction or recovery. In addition it is often necessary to record moisture, pulp density, or dilution, percentage of weight of oils and reagents employed; screen analyses of grinding conditions, oversize, etc.; assay values of non-valuable or interfering substances; cost data; and such special information as may be required. GRaphic Presentation . Close analysis is necessary of a daily operation involving such a number of factors, the relation and influence of which may be of great importance in the treatment scheme. When the analysis is made from a numerical tabulation, the chance for one or more obscure, but perhaps important, factors to escape notice is considerable, therefore the need for an accurate, readily digestible presentation of metallurgical data is obvious.. Graphic records of milling operations are frequently used, but owing to the wide range of magnitude and values, and the number of factors involved, the customary practice of assigning different values to the same ordinates, as in Fig. 1, results in a complex and intricate record which makes little appeal to a busy operating official. The methods shown in Figs. 2 and 3 are devised to display such data in a clear and legible manner, without confusion.

Jan 1, 1920

By C. S. Trewin

ZINC, in its wrought form, is produced commercially in rolled strip, sheet, wire, rod and tubing. Wire has been made periodically, but due to the fact that slight drafts are necessary, the cost of production is greater than for the more common non-ferrous metals which are made into wire. Notwithstanding the cost, zinc wire has certain special uses for which it is particularly adaptable. Rod has been made both by rolling and extrusion, the product, however, has not indicated great commercial value. Tubing has been made from strip from time to time by forming a strip around a mandrel and either electrically or gas-welding a longitudinal joint. Recently a tube manufacturer has succeeded in making a fair quantity of this material. Its commercial adaptability is still to be determined but anyone who desires it can obtain quantities of the smaller sizes. Inasmuch as strip and sheet are commercially the most important, this paper will be devoted to these products. In the broader sense, zinc is not alloyed. That is, there are no combinations comparable to the various copper, aluminum and nickel alloys. It has been recognized,, for some time, that the lead and cadmium occurring with commercial zinc have some effect on its properties and such alloys as may be said to exist are those made from zincs containing varying amounts of lead and cadmium with a relatively low iron content. The foreign rolled zinc will analyze higher in lead than the domestic grades. A representative foreign analysis will run 1.1 per cent. lead, 0.07 per cent. cadmium and 0.02 per cent. iron. The American grades vary from zinc approximating high grade. and analyzing 0.08 per cent. lead, 0.002 per cent. cadmium and 0.015 per cent. iron, to the lower grades in which the lead will vary from 0.3 to 1.0 per cent., cadmium from 0.10 to 0.5 per cent. and the iron in the neighborhood of 0.02 percent.

Jan 1, 1927

By A. W. Ambrose, C. E. Beecher

It is the purpose of this paper to summarize data on unitization projects in Oklahoma and Kansas as obtained from replies to questionnaires sent out by the A. I. M. E. committee for these states. The information received indicates that unitization is growing rapidly in this area, but has not been in operation for a sufficient length of time to develop production history. It was impossible to obtain a record of all unitization projects in the time available. The magnitude of such projects is indicated by the fact that reports were received covering a total of 171,420 acres in Kansas and 49,350 acres in Oklahoma. Most of these units have been formed during the past 2 years, the greater number having been completed in 1929. It is anticipated that even more will be formed during the present year. The following important facts have been emphasized by answers to the questionnaire and discussion with various operators: 1. Unitization is growing rapidly, as evidenced by the number of units and the large total acreage now included in units as compared with practically no acreage 2 years ago. 2. Operators are convinced that unitization is reducing development and operating cost and they anticipate greater reductions as experience is gained in unit operation. 3. Producing units have not been in operation for a sufficient length of time to give significant production history from which to estimate the ultimate recovery of oil, but the general opinion seems to be that more oil will be recovered. 4. In view of the benefits to be derived from unitization, many operators are refusing to carry on wildcat operations unless a unit has been formed. If this attitude continues to grow there will be no large pools developed in Oklahoma and Kansas in the future except under unit control. Summary The following tabulation gives a condensed summary of the information received on unit operations in Oklahoma and Kansas, but does not include all units, because many were not reported.

Jan 1, 1930

By William Firmstone

On the 19th December, 1833, a patent was granted to F. W. Geisenheimer, for smelting iron ore with anthracite. In his claim he says: " Sixthly, though I cannot, and do not, claim an exclusive right of the use of heated air, for any kind of fuel, nevertheless I believe to have a right to claim the use of heated air, applied upon, and in connection with, the said principle and manner discovered by me, to smelt iron ore in blast-furnaces with anthracite coal, by applying a blast of air in such quantity, velocity, and density, or under such pressure, as the compactness, or density, and the continuity of the anthracite requires, as above amply and fully described and illustrated." Dr. Geisenheimer made experiments in smelting iron ore with anthracite at the Valley Furnace, near Pottsville, but he failed to carry out to good practical results the principles enunciated in his patent. In the .Joozcrnal of the Franklin Institute for February, 1838, a communication was published that was made by Mr. George Crane, of the Yniscedwyn Iron Works, South Wales, to the British Association, in September, 1837. On the smelting of iron with anthracite coal, Mr. Crane states therein, that he began the use of anthracite with hot-blast on the 7th February, 1837, in a cupola blastfurnace, 41 feet high, and 10 feet across the boshes ; product, 34 to 36 tons a week. Mr. Crane goes on to say, "It may not be uninteresting to be informed in what matter the idea first occurred to me of applying a heated blast to anthracite coal. One evening, after I had placed a piece of it upon my parlor fire (which had before been made up with bituminous coal), arid had allowed it to arrive at a red heat, upon applying as fierce a blast to this piece of coal as I could raise from a pair of bellows, I noticed a black spot or mark

Technology has no recognized rank in what is called polite literature; the subject-matter of engineering is not supposed to lend itself to artistic treatment; we are the hewers of wood and drawers of water to the high-priests of learning that live on the cold summit above our humbler dwellings. Therefore the hierophants smile at the notion of 'style'- “that curiously personal thing”--in technical writing. The "great art" of Pater, the "inevitable phrase" of Raleigh, the "note of distinction" that Arnold demanded are said to be beyond the scope, as they are supposed to be beside the need, of a writer on geology or engineering. This is a narrow view. Science, no less than belles lettres, calls for the best exercise of the human intelligence; the art of writing should be employed as skilfully and as earnestly in a description of the structure of the Sierra Nevada, or of the construction of a tunnel through the range, as in a rhapsody welcoming the rosy fingers of the dawn. The idea still lingers that fine writing does not befit technology, even though the masters of the Victorian period- Huxley, Tyndall, Ruskin-proved that science is worthy to be arrayed in the best robes that the looms of thought can weave. At the beginning of these lectures I quoted Barrie's remark touching the inability of the scientific man to express himself. That imputation has been passed to the technologist, whose utilitarian pursuits are supposed to make him too clumsy for the refinements of human speech. We may not have acquired the self-consciousness of those writers on Art whose "power of expression is so cultivated that their sensual caterwauling may be almost mistaken for the music of the spheres"; nor can we imitate the politicians, who have the ability to speak far beyond anything that they may have to say; but we too have a litera-

Jan 1, 1931

Discussion of the paper of IRVING A. PALMER, presented at the Salt Lake meeting, August, 1914, and printed in Bulletin No. 91, July, 1914, pp. 1447 to 1460. L. S. AUSTIN, Salt Lake City, Utah.-With the union of the Guggenheim interests and the American Smelting& Refining Co. in 1900, competition among the lead-smelting companies appeared to have been largely eliminated. This condition prevailed for but a short time, owing to the erection of smelteries by competing companies. Naturally, as competitors, the older companies endeavored to keep improved methods to themselves, not realizing, it would appear, that such knowledge could never be bottled up, but would drift into the common field of practice. Of late it has begun to be felt that more is gained than lost by adopting a franker and more open policy. The line, however, is drawn in. giving details of costs, which, fully known, it is felt, would be taken advantage of by a rival. As Mr. Palmer says, steady and substantial progress has been made, and latterly, I may add, the improvements have been radical. Sintering by the Huntington-Heberlein method or with Dwight-Lloyd machines has effected an important saving over reverberatory roasting, the cost being, say, 50 to 75c., as compared With $2 per ton by the older method. Moreover, the .large use of a sintered product has resulted in doubling blast-furnace tonnage. However, the change has not been an unmixed blessing, as in the machine roasting little time can be given to the breaking up of the blende, and it has been impossible to decompose largely the zinc sulphide, so detrimental in later blast-furnace treatment. The satisfactory roasting of the blende is still an unsolved problem. Nor is this all. For the best reduction it has been found that a part of-the change should be crude (unsintered) ore, indicating that the already fused material is only too ready to change to slag, thus lessening the opportunity for better reduction.

Jan 11, 1914

By Joseph E. Pogue

Price is a complicated concept, for price is both a cause and an effect. This reciprocal aspect is commonly overlooked and the oversight is the source of many economic maladjustments. Price is the resultant of the ratio between supply and demand, but it differs from a mathematical concept of a proportion, by itself constituting an economic force which continuously alters the elements that determine the relationship. Price, therefore, is not merely the outcome of other forces but is in its own right one of the most powerful of economic agents. Price accordingly does not play a passive role; nor can it be sterilized or rendered inactive. In consequence, price cannot be fixed or at least kept fixed, except by the elimination of all freedom of choice on the part of producers and consumers. A primary objective of all economic activity is equilibrium. The same is true of a unit of economic activity, the single industry. The plane upon which equilibrium centers may shift in the course of time, but equilibrium itself is the point of departure and the point of return. If an industry is in equilibrium, that industry is operating effectively. The motivating forces of an industry—profits or the common good—are not to be confused with the prerequisite of equilibrium, but this mistake is often made. The producer is dominated by the profit motive; the consumer, or his collective representative, by the general welfare motive. No one is the advocate for equilibrium; that status is supposed to be arrived at automatically. If the forces of competition are perfectly free, such is the tendency. Equilibrium For the purposes of this analysis, equilibrium needs to be broadly defined and is conceived to involve: (1) balance between supply and demand; (2) internal equipoise amongst the elements within an industry; and (3) symmetry in respect to the whole economy. This definition implies flexibility and case of adjustment; a ready accommodation to change. Equilibrium does not postulate profits or nonprofits, social objectives or the lack of them. A decadent industry may be in equilib-

Jan 1, 1937

By Edward A. Sayre

In shaft sinking for cod mines, the cost item greatly influences the method adopted. This holds true especially when soft material must be traversed. The average life of a coal mine is short. This is due either to the limited area of the coal basin or to the great expense of maintenance and haulage underground when the entries are extended a considerable distance from the hoisting shaft. Therefore, the engineer in opening a coal mine is confronted with the fact that the cost must be kept within certain bounds else the venture will prove unprofitable. For this reason he may be prohibited from adopting certain safe, but expensive, methods that are used in sinking caissons for foundations, driving transportation tunnels, or other work of permanent construction. A common method of sinking through difficult ground employs the aid of a steel shoe pushed ahead of the shaft timbers. Another is the drop-shaft method. These two methods were used in sinking the main shaft and the air shaft of the Eagle No. 3 mine, at Des Moines, Ia., and the following data show the relative success and cost of the two methods of sinking under the same conditions. A drill log of the material to be penetrated was as follows (see Plate 1, Fig. 1): Thickness, Total Depth, Ft. In. Ft. In. Drift................................... 38 38 Sand..................................... 2 40 Drift.................................... 2 6 42 6 Jointed clay.............................. 5 6 48 Drift, firm............................... 10 6 58 6 Clay, with sand streaks.................... 3 61 6 Sand.................................... 12 73 6 Shale, with two thin beds of coal and thin strata of rock......................... 86 6 160 Rock.................................... 5 165 Coal..................................... 3 9 168 9 Main Shaft Sunk by Steel-Shoe Method This record shows the first 73 ft. to bc of drift material, the lower 12 or 15 ft. of which was sand. The remaining 92 ft. to the coal was shale and rock, and offered no trouble in sinking.

Jan 1, 1917

By Robert W. Hunt

PeRhaps of all the scientific economic questions which have been claiming the attention of capitalists, metallurgists, manufacturers, directors of public utilities, and the general public of America, during the last few years, none have been of more importance than the one relating to the wear and safety of steel rails. The discovery of the Bessemer process made possible modern railway development. In that growth, as has generally happened in all progressive movemeuts, all its departments have not remained equally balanced. Iron rails permitted the construction of roadways for the passage of power-driven vehicles. In time the speed and weight of such carriages proved too much for the wearing-qualities of the rails, and the limit of railway capacity seemed to have been reached. Bessemer made his invention, which was soon perfected and developed, especially as related to steel rails, and thereby increased the limit of capacity, and vastly greater railway progress was made pgssible. The Siemens-Martin open-hearth process followed, and was later supplemented by the Thomas-Q-ilchrist basic improvement. For a time the Bessemer steel rails of commerce were more than equal to all that was asked of them, but this did not long continue, as evidenced by the records in our Tansactions. Revolutionary changes occurred in the industrial world, and in no part of it more than in steel-rail manufacture. Great and powerful commercial combinations were made, whose financial resources made possible the supplanting of the then most efficient blast-furnaces, steel-works, and mills, by others of theretofore unimagined capacity. Old traditions and practices of steel-making were wiped away, and, in too many cases, output was apparently the chief aim, with the result that much dissatisfaction with the wear and safety of rails was felt by railway officials, and the general public was concerned as to its safety when traveling. The climatic conditions of the winter

Jan 1, 1913

By Oswald J. Heinrich

IN the coal review for the United States for 1875, the Engineering and Mining Journal, January 1st, 1876, remarks about the Richmond coal basin " It has contributed but little to the supply of fuel during the year past, notwithstanding the fact that it is the most favorably situated of all our coal-fields, and possesses a fuel of good quality, well adapted to many important uses. An unaccountable lethargy seems to have fallen on all who have touched this field ; and yet, in the future it can scarcely fail to become one of the great sources of coal supply." In most respects indorsing the above remarks, I take occasion to lay before the Institute the following facts in defence of the Rich¬mond basin; and not willing to criticize other mining enterprises in this field, I will make this one remark in general for all of them. While it is true that very little coal has been raised during the year in this field, it is equally true that even the little that has been raised could hardly be sold. When the output of the largest coal districts in the United States decreases, in consequence of the state of the market, it is not to be wondered at that the former small output of this basin dwindled down to almost nothing. But a far deeper¬seated evil, under which this field is suffering, may be discerned from the following remarks, which I hope will show that the latter part of the above remark in the Journal is not altogether fair. As the history of one mine in this district very nearly represents the history of the whole field, I will endeavor to give an account of the development of the Midlothian Mines, ranging amongst the old¬est in the district, partially taken from a report of Col. Wooldridge, in 1841. Coal was mined in this neighborhood as early as 1700, and used (then so-called extensively) in the vicinity in 1775. A

Jan 1, 1876