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By AIME AIME

THANKS to the excellent preliminary work of: the Division officers and the local committee the fall meeting of the Coal Division at Bluefields was a brilliant success. West Virginia was at its best with its beautiful mountains, good roads and foliage, just beginning to turn to autumn colors. The meeting began on time and was kept on time throughout. The papers were-well prepared and, being on subjects of live interest, provoked 'lively discussion. One factor in bringing this about was that they were not too numerous and that with one exception copies had been submitted in advance a sufficient time to permit of them having been studied. The Friday morning session was presided over by John .J. Lincoln of the Crozier Coal and Coke Co. and president of the Pocahontas Coal Operators Association. After brief announcements by Thomas H. Clagett, chairman of the local committee, regarding plans for the two day's involved, and by Howard N. Eavenson, chairman of the Division, the reading of papers was taken up.

Jan 1, 1931

By H. OSBORG

THE patent literature of alloys for the last two decades or so indicates that the number of liatents referring to smaller and smaller percentages of essential alloying constituents is on the increase, whereas the number of patents relating to considerable percentages of alloying additions becomes smaller. The claims regarding physical properties indicate consistently higher and more rigid values and show the possibility of modifying the physical properties by only slight changes in the percentage of minor constituents or by applying different methods - of treatment. Alloys of the same base have been made suitable for a number of different applications by intelligently and rigid- ly controlling their composition, melting, casting, working, and heat-treatments. Other trends indicated in the development of modern alloys are higher corrosion resistance, higher fatigue limits, and "stability" in volume.

Jan 1, 1937

By David W. Brunton

(San Francisco Meeting, October, 1911.) MINE-DRAINAGE and the ever-increasing demand for water on the plains have within the past few years necessitated the driving of a great number of adits and tunnels, including many of considerable size and great length. In most instances, ex isting conditions have called for extreme rapidity of execution; and this necessity, coupled with the high altitudes at which most of the work has been carried on, excessive freight-rates, and difficulty -of access, has involved many complex and interesting problems. One of the most rapidly executed undertakings of this class is the Laramie tunnel, recently completed for the Laramie-Poudre Reservoirs & Irrigation Co. This tunnel is driven through Green ridge, a spur of the Continental Divide, which separates the Laramie river from the Cache-la-Poudre in Laramie county, Colo. Green ridge is extremely persistent, and further northward in Wyoming is known as Sherman hill, the highest point on the Union Pacific railway. At the point where the tunnel is driven, two opposing bends bring these streams within 2.5 miles of each other, with a difference in elevation of 500 ft. The rock exposed on the banks of the two rivers does not differ materially in hardness; and, without a geological study of the conditions involved, it would appear that the difference in the depth of erosion of the two streams is due principally to the greater volume of water at this point in the Cache-la-Poudre, which has a drainage-area above the tunnel-portal of 110 sq. miles, as against 30 sq. miles of natural drainage for the Laramie. To increase the water-supply at the tunnel, however, this latter amount has been augmented by two side collection-canals, which bring the available drainage-area up to 84 square miles. The nearest railroad shipping-point to the eastern portal is

Apr 1, 1912

By Jennings S. Cox

(Glen Summit Meeting, June, 1911.) THE following notes, prepared in 1908, as the result of a personal examination and extensive explorations under my direction in 1906, have been revised and greatly augmented after two subsequent visits and further explorations in 191.0. The hard iron-ores of the south coast of Oriente Province, in the island of Cuba, have been known for many years, in fact one mine has been in operation for more than 20 years ; but it is only within the past four years that the large mantle-deposits of brown ores of the north coast have attracted serious attention. A. C. Spencer 1 has described these ores in a paper, entitled Three Deposits of Iron Ore in Cuba, which refers to the Mayari, Moa, and Cubitas deposits. C. M. Weld,2 in a scholarly paper on The Residual Brown Iron-Ores of Cuba, has discussed the character and possible genesis of these deposits with particular reference to the Moa field, calling attention also to the Taco and Navas fields in addition to those described by Spencer. Descriptive articles with reference to the Mayari field, and a few words about the Moa deposit, have also appeared.3 It is the purpose of the present paper to give some account of the exploration of the Moa deposit and to call attention to its commercial importance. LOCATION. The Moa district is situated on the north coast of the . Province of Oriente, which is the most easterly province of the island of Cuba. It lies on the northern or seaward slope of 1 Bulletin No. 340, U. S. Geological Survey, pp. 318 to 329 (1908). 2 Trans., xl., 299 to 312 (1910). 3 Iron Age, vol. lxxx., No. 7, pp. 421 to 426 (Aug. 15, 1907), and vol. lxxxi., No. 15, pp. 1149 to 1157 (April 9, 1908).

Mar 1, 1911

By S. D. Warriner

ONE of the most, if not the most, difficult of the problems associated with the mining and distri-bution of anthracite is to get clearly into the minds of the consumers and of the editorial and reporto-rial writers in the public press the relationship between the cost of production, the price at the mine and the price that the consumer pays for his coal, delivered in the cellar. One sees in his morning paper a statement to the .effect that out of the $12 or $13 per ton that his dealer charges him, the miner gets only $2 or even less, and he asks himself or the paper asks for him, "Who gets the difference?" Not infrequently the amount that the miner gets is given for run-of-mine bituminous coal while the price quoted is that of prepared anthra-cite, egg, stove, or chestnut, as the case may be, delivered to the bin of the consumer; and the difference stands out with all the more prominence; and it sticks in his memory with a persistency which no manner of explanation is able to efface. A recently published official report for the year. 1921 of one of the State Bureaus stated the total production of anthracite in net tons of 2000 lb., and included not only the output recovered by washeries from old culm banks and by dredges from creek and river channels, but also the colliery consumption;, i.e., the coal used by the companies in the operation of the collieries. This resulted in a total production of 90,509,075 net tons for which the labor cost was stated at $283,961,300, or $3.13 per net ton, equivalent to $3.50 per gross ton. This figure of $3.50 was immediately seized upon as representing the labor cost per gross ton of fresh-mined commercial coal. It is almost a hopeless task to try to correct such errors of statement in the first place, and, in the second place, to correct the misapprehen-sions that arise from them. As a matter of fact, the report was misleading in regard to the labor cost of the entire production shipped, as the coal used for colliery consumption should be deducted. Correctly stated, the report should have shown, calculated in terms of gross tons of 2240 lb., the legal weight in Pennsylvania, as follows: Gross production 80,607,359 tons Less colliery fuel 8,757,137 tons Commercial production 71,850,222 tons Total labor bill $283,961,300.00 Labor cost per ton...: 8 3.952 The foregoing figures" of tonnage are obtained from the State Department of Mines. Even these include the quantity recovered from calm, banks by washeries, and consequently the $3.95 arrived at as the average labor cost is somewhat less than that actually involved in the mining of fresh-mined coal. Unfortunately, the figures of washery production and the cost of producing it are not available.

Jan 7, 1922

By William M. Sheehan

TRANSPORTATION is one of the most important problems of the mine operator and the possibilities of cost reduction in this field should not be overlooked. In the railroad industry, cars and locomotives have been improved greatly, and the progress there made is well worthy of study by the mine operator looking for maximum efficiency in every branch of his activities. One of the outstanding developments in the construction of railroad equipment in recent years has been the wide-spread adoption of large one-piece steel castings for the framework of locomotives, passenger and freight cars. Some of the advantages and applications of this type of construction will be outlined in this paper, with particular thought of the needs of the mining industry. The inherent qualities of cast steel: homogeneity, unrestricted size and shape, high tensile strength, flexibility of metal distribution, resistance to corrosion, and gracefulness of outline, make it the most versatile member of the ferrous group. Not only is it a strength-giving element, but it is corrosion resistant, a combination that makes for large economies in equipment maintenance. Flexibility of metal distribution allows the integral foundation to be in the shape best suited for the purpose. These cast structures are really assembled in the mold in liquid form and the metal can be placed in the right pro¬portion exactly where it is needed, thus securing weight economy and uniformity of fibre stress. Such a process permits the incorporation, with ease, of necessary brackets, utilizing them to provide not only greater strength for the derail part itself, but often to add to the value of the entire unit. Laps, seams, and joints, which are necessary in all fabricated forms, are eliminated.

Jan 1, 1933

By Strathmore R. B. Cooke

On the basis of experiments con- ducted on quartz using a bubble pick-up method, it was shown in an earlier paper1 that this mineral will preferentially adsorb hydrogen, calcium, or sodium ions, depending on the relative concentrations of those ions in the solution in which the quartz is immersed. For quartz particles ranging in size from 0.2 to 1 mm, it was demonstrated that the concentration of calcium in solution (assumed present as ions) necessary to completely activate quartz for flotation is given by the expression: In this expression, ionic concentrations are in mols per liter. It was further shown that the pick-up method is apparently more sensitive to changes in reagent concentration than the standard captive-bubble method, and that induction times are apparently much reduced. Since completing these earlier tests, a new type of cell has been constructed; this is shown in Fig 1 and 2. In Fig 1, A is a ground joint, B is a ceutral tube reaching to within a few millimeters of the bottom of the cell, and C is a stopper which may be removed for re- agent addition, and serves the further purpose of excluding carbon dioxide from the air during the test. The entire cell is constructed of Pyrex glass, and does not give the trouble experienced with the earlier cell, in which activating ions were released from the glass at high pH values. The only critical factor in the construction of the cell is the clearance between the central tube and

Jan 1, 1949

By Frank L. Hess

BERYLLIUM is demanding more of the limelight, and the output of beryllium copper (containing 2% to~ 3 per cent of beryllium) seems to have grown 60 per cent above that of 1936, which was double that of 1935. There is increasing interest in beryllium-aluminum alloys and small quantities are being marketed at $50 per lb. for the contained beryllium. Other alloys also can be produced. Further price decreases for beryllium copper (now $23 per lb. for the contained beryllium) seem , possible and desirable. No difficulty has been experienced in obtaining beryl and a 'reserve stock has been built up. One supplier heretofore found reliable has offered to furnish 200 tons per month. Supplies during 1937 have come from the Black Hills in South Dakota, Colorado. India, and South America

Jan 1, 1938

By Malcolm T. Hepworth

RECENT interest in thermoelectric devices has been directed toward studies of the properties of thermoelectric materials of semiconducting solid compounds with little attention given to ionic and semiconducting liquids such as aqueous solutions, fused salts, and mattes. One type of thermoelectric system is the thermocell: a nonisothermal galvanic cell with two identical electrodes at different temperatures connected by an electrolyte bridge. An electromotive force, v, is generated which is a function of the electrode reactions and the properties of the electrolyte according to the Eastman' equation: where S* is the entropy change of the system arising from the electrode reactions and by heat transferred by ion migration and by thermal conduction. The quantity nF is the product of equivalents passed and Faraday's constant. A value of S* of 23.06 cal per "C is equivalent to 1 mv-Faraday per "C. The symbol, a, is used for dV/dT in analog to the See-beck coefficient of solid-state thermoelements. de Bethune2 has calculated the temperature coefficients of the electromotive force of a large number of nonisothermal aqueous cells from measurements on the nonisothermal temperature coefficients of the standard hydrogen electrode, combined with data on the isothermal temperature coefficients of half-cells tabulated in the literature. Values of these coefficients (a) in de Bethune's compilation ranged up to 3 mv per C. In particular he reported a value of +2.059 mv per "C at 25'C for the cell: Fe (aqueous, unit activity) (aqueous, unit activity) written for the hot-electrode reaction. The positive sign indicates that the hot electrode is positive (an "n-type thermocell"). In analog to a solid-state p-n system, it would be possible to couple two thermocells together to form a system in which the figure of merit could be calculated by adding the temperature coefficients according to the relationship described by offee:' where a is the Seebeck coefficient in volts per "C, p is the specific resistivity in ohm-cm, and K is the thermal conductivity in watts per cm "C. Even though ionic systems have rather high electrical resistivities compared with semiconducting and metallic systems, it was felt that a preliminary study of one ionic system should be made to establish some basis for evaluating the possibility of a p-n thermocell for energy conversion. Accordingly the Fe", Fe"' system was studied as a possible component for a p-n system. A glass system was constructed consisting of two vertical water-jacketed tubes connected by a horizontal tube, Fig. 1. Platinum-black electrodes 1 cm by 1 cm in dimension were inserted in each vertical tube with thermometers to register the electrode-compartment temperatures. The temperature of the electrode compartments was controlled by circulating water from thermostatted baths around the electrode compartments. The electromotive force of the cell was then read by a potentiometer for zero current as a function of the temperature of the hotter electrode. Current output of the cell for varying external loads was also measured. The cell resistance was measured by means of a bridge circuit with 10,000 cps signal and oscilloscope. Resistance measurements were converted to specific resistivity by calibrating the cell with a solution of known conductivity.

Jan 1, 1965

By Howard I. Young

WHEN so many statements are being made relative to the requirements of zinc metal, it is difficult for some of us who are acquainted with the industry to visualize how it is possible to step up production so as to supply some of the fantastic requirement figures that are published from time to time. I shall attempt to approach this subject from the standpoint of existing conditions which affect production, also keeping in mind the price ceiling under which the industry operates. Total production of primary and secondary zinc in the United States for 1941 will be about 878,000 tons, to which should be added about 36,000 tons of Mexican slab zinc available for consumption or export from the United States, giving a total available of 914,000 tons. Production of slab zinc of all grades in 1942 should be 953,000 tons. Adding the available Mexican supply should bring the total to 989,000 tons.

Jan 1, 1942

By A. Ross Rornmel

ABILITY to speak effectively is one of man's most longed for and coveted abilities. It is the ability to stand on one's feet, transfer knowledge and thoughts to others, to reach an objective professionally or otherwise by leading groups through a channel of planned thought. Each day group speaking plays an important part in making or marring success, and the engineering profession often provides this opportunity and requirement. An ability to speak effectively develops courage, poise, confidence, and prestige for the speaker. The technical man cannot be reluctant to face an audience. He is often called upon to do this in presence of employees, supervisors, and other groups. His ability to speak effectively is as much a requirement as the fundamentals of his profession. The three fundamentals of effective speaking are: (1) Enthusiasm and Confidence. These are joined because of their close relation. (2) Preparation. This includes knowledge of the subject. (3) Presentation. By this is meant the features of delivery.

Jan 1, 1946

By CHARLES M. SCHWAB

THE ENGINEERS have placed this great country of ours in a preeminent position with everything pertaining to manufacture, metallurgy, and the kindred arts. We are second to none in the world. We have a country which, another speaker has said, God has endowed with such riches in coal and natural resources as no other country in the world. But rich as these are, there is one thing greater; the sturdy character, energy, and integrity of its people, which will make these great resources an influence in the world's developments. Great as are these resources and the energy and integrity of our people, there is one problem of our .engineering, which I term human engineering, that is of far more importance than the creation of machines and methods, with which you have been so successful in the past. Of what value is the skillfully devised machinery, the complex process, unless manned and operated by people whose heart and soul are in sympathy with the work they are doing and who have before them the giving of a complete day's work for a day's pay?

Jan 1, 1920

By Brahm Prakash, R. Schuhmann

Maurice Rey—It may be interesting to note that depressing effects can also be obtained from cyclic compounds other than dyes. One such compound which is a dispersing agent for carbon, pigments and other compounds is known in France by the trade name "dispergine" and in the United States by the name of Lomar P W (Jacques Wolf & Co.) Dr. Rey admits that the compound is not very selective and is similar in its action to starch and dextrin.

Jan 1, 1951

By Brahm Prakash, R. Schuhmann

Maurice Rey—It may be interesting to note that depressing effects can also be obtained from cyclic compounds other than dyes. One such compound which is a dispersing agent for carbon, pigments and other compounds is known in France by the trade name "dispergine" and in the United States by the name of Lomar P W (Jacques Wolf & Co.) Dr. Rey admits that the compound is not very selective and is similar in its action to starch and dextrin.

Jan 1, 1951

By Morris Cohen, Robert C. Ruhl

The phases in Fe-C alloys over a wide composition range have been studied after splal quenching from the liquid state. Binary alloys containing 0 to 5.1 wt pel C as /cell as a large number of ternary Fe-C-Si alloys with 2.5 to 5.0 wt pct C and 0.3 to 5.1 wt pct Si were attlong those sludied. Olher Fe-C-X alloys, zcilh X being Co, Cr, ,Wn, Ni, and Ru , were also inrestigated after splat quenching. At high carbon contents, a new hcp phase (designaled 6 phase, but different from e carbide) is retained upon splat quenching. The .fraction of this phase varies up lo 97 pcl for a Fe-4.K-1.9% alloy. The composition of the E phase ranges from about 3.8 10 4.8 wt pet C, and the corresponding laltice parameters increase linearly ulith carbon content, while the c/a ratio remains essentially conslc~nl. The E phrtse appears to he a solulion of carbon in E iron, the latler being nornially found only at high pressures. It is deduced that the unit cell of the E phase corresponds to the formula Fe12C3, and llzal il is relaled to tlie ordered slruclures 0.f 6 iron carbide and c iron nilride. The E phase is compared and contrasted to the olher known carbides and nitrides of iron and nickel. An exlrapolaTion of the atomic volume 1,s carhon conlent of /he E pllase lzcts giz.en a neu7 estitnale jor /he alomic volume of E iron, 11.30 cu A, a1 atmospheric pressure and temperature. Other alomic volume relalionships lead to /he co~zpositioti Fe2.iC tor E iron carbide, /he unit cell fortr~ula being -Fe2rClo The E phase undergoes a lulo-slage decomposition upon healing, .forrning firsl rnarlensile plus E carhide, a/ler 1 hr at 140" lo 200°C, slid then ferr ite Plus cementile, after 1 lir a1 330" to 460°C. A1 carbo,l contents between 1.5 and 3.0 LC/ pcl, (he predo.wirzar/t plzase alley quenching is fcc austenite. The retained carbon content of this phase increases with itlcreasing silicon in certain concentration ranges, reaching a maximum of 2.37 wt pct C itz a Fe-2.6C-4.OSi alloy. This is the highest carbon conten1 reLaitled in austenite to date. These high-carbon aus-tenites can be partially tm?zsforttled lo tnartensile hy severe deformation in the temperature range of — 190 to -50°C. TECHNIQUES for splat quenching from the liquid state have been utilized in numerous recent investigations to produce metastable phases in a variety of alloy systems. Among the several ways of splat quenching, the shock-tube method appears to yield the highest cooling rates1-3, 7, 8 and was adopted here. Estimated cooling rates attained in the present experiments ranged from 10' to 10 80Cper sec.' As a part of a research program on interstitial al- loy phases, the Fe-C system was selected for splat-quenching studies. It was hoped that splat quenching would allow high metastable supersaturations of carbon to be retained in solution. Also of considerable interest were the conditions governing the occurrence of the various intermediate phases upon solidification. The alloys investigated included both binary Fe-C compositions as well as six ternary Fe-C-X alloy systems. The known phases in the Fe-C system are summarized in Table I.* Only the ferrite and graphite are ent investigation.14 and is described in detail herein Table II summarizes corresponding data on Fe-N phases, which are also of interest here because of their similarity to the Fe-C phases. EXPERIMENTAL PROCEDURES Alloys were prepared by melting the elements. 99.9 pct purity, in an inert gas nonconsumable electrode arc furnace. The buttons. weighing about 5 g. were remelted twice. were then fragmented. and their interior surfaces were examined for uniformity: if any doubt existed. they were remelted again. Chemical analyses were performed on all the alloys. the accuracy being about k0.05 wt pct. At high temperatures, carbon-containing alloys react with alumina crucibles as follows: If the atmosphere in the splat-quenching furnace does not contain sufficient carbon monoxide the alloy can be depleted of carbon and contaminated with aluminum. Calculations and experimental observations showed that 50 to 100 torr CO partial pressure effectively blocked the above reaction in all the alloys investigated. The splat-quenching equipment in Figs. 1 and 2 provides for evacuation and back-filling with CO-Ar mixtures. The furnace is capable of operation up to 1650°C. and the gettering action of the graphite heating element reduces the oxygen partial pressure in the furnace atmosphere to below 10-5 torr, thus preventing oxidation of the specimens.

Jan 1, 1970

By HOWARND N. EAVENSON

THE year 1930 resembled the preceding one in the coal industry in continuing the era of falling prices and 'of the abandonment of unprofitable mines. Practically all coal prices fell, and in the steam sizes during the last half of the year this was particularly true, due to the small industrial demand. No new mines of any size were opened in the bituminous coal industry, but there was a steady increase in the number of cleaning plants of all kinds built in all fields. It is estimated that at least nine million tons per year were added to the previous total of washed coal. The largest washing plant started during the year was that of the Buckeye Coal Co., at Nemacolin, Pa., with a capacity of 650 tons per hour. Fig. 1 shows - the mixing-bin, conveyor galleries, washing-plant and skip hoist, and Fig. 2 the 120-ft. Dorr thickener for collecting the 48-mesh material from the wash water. Dryers are used for drying the steam coal product. The following statement by J. R. Campbell shows the effect of cleaning on Pittsburgh coal in Greene County: "With the advent of the 650-t.p.h. efficient washing plant in Greene County at the Nemacolin mine of the Buckeye Coal Co., it has undoubtedly been demonstrated that the potential coking-metallurgical coals of the county can be brought within the pale of the highest grade high-volatile coals for steel manufacture. A few months' operation indicates that 9% per cent ash in the raw coal can be easily reduced to under 7 per cent ash in the washed coal and the sulfur from 1.60 per cent in the run of mine to 1.20 per cent sulfur in the washed coal.

Jan 1, 1931

By Graham Bright

T HE chairman of the Mines Committee of the A. 1: E. E. for 1920-21 has had the honor of being also the chairman of a similar committee, the Mine Equipment Committee, of the A. I. M. E. It has been the endeavor during the past year to have the two committees work together since the object of these committees is very much the same. A meeting of the committees was held in Chicago in November of 1920, at which time it was decided that one of the best ways to work together would be to foster joint meetings of the local sections of the A. I. E. E. and A. I. M. E. By these meetings, it was hoped that various engineers in the local sections interested in mining subjects could be brought together and not only become better acquainted but be greatly benefited by the interchange of ideas and by the discussion of papers presented on mining subjects.

Jan 1, 1921

By E. R. Kaiser

ACTIVITY on long-range and on immediate wartime problems shared the attention of specialists in coal research during 1943. Programs of the principal coal laboratories were more adequately financed than in previous years, but all reported shortages of technical personnel. Expansion in coal research in the year to come will depend primarily on the availability of qualified research talent.

Jan 1, 1944

By J. Robert Van Peli

IT was a strange but highly fruitful marriage-that union of hardy explorers, seeking the rich treasures of copper in the Lake Superior wilderness, with Boston's aristocracy of brains, capital, and enterprise. This historic wedlock, which has continued happily to the present day, was the means by which the wealth of Lake Superior's copper was won for the use and benefit of an expanding America. One branch of this family tree, the western branch, begins with prehistoric Indian miners, embraces the early French explorers of the Upper Lakes, and finally includes the British and American pioneers who reduced the vague rumors of copper to known fact and actually began the mining of copper in the wilderness. The other branch, the New England line, begins

Jan 1, 1948

By Elmer W. Pehrson

Minerals have played a prominent role in the affairs of man and nations since time immemorial but with the advent of the industrial revolution, expanding use of the products of the mineral kingdom became synonymous with the material progress of mankind. Individuals and business groups have recognized this fact so have been aggressive in searching for and utilizing mineral resources, with notable success. Indeed, their achievements are primarily responsible for the present Machine Age. On the other hand, until recently the body politic has failed to grasp fully the essentiality of minerals although, at times, access to mineral supplies has been an important factor in the political maneuvers of nations. This chapter is concerned primarily with the broader political and economic relationships of mineral resources to the world economy, and with the internal and external actions of nations in the field of minerals. Many factors that condition the mineral economy of regions and the world as a whole, influence the internal and external affairs of individual nations. The more important of these are: 1. The nature of man's dependence on minerals. 2. The problems resulting from the unique characteristics of mineral occurrence. 3. Geopolitical concepts. 4. Minerals and world power. Actions of individual nations affecting their mineral economy seek two basic objectives: 1. Attainment and maintenance of prosperity. 2. Military security. Other objectives may be cited but on careful analysis they become integral parts or extreme phases of the two points noted above. For example, the twentieth century aggressions of the USSR, Germany, Italy, and Japan might be considered as direct bids for world power but they also can be interpreted as exaggerated or mistaken efforts toward military security and peacetime prosperity. Similarly, trade barriers, nationalization of industries, foreign exchange manipulations, taxation, monopolistic prac-

Jan 1, 1964