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By T. Wasson

The same limitations' that characterized 1931 existed in the old fields of Indiana and Illinois during 1932. Prices remained low. The average for the year for Illinois and southwestern Indiana was $1.032 as against $0.852 for 1931 and $1.616 for 1930. In September a curtailment of production of about 25 per cent became effective and was continued to the end of the year. There were no new discoveries and very little wildcatting was done. Considering the age of the wells, and the number still producing, there were few abandonments. The most outstanding thing about the old fields in these states is their long continued productivity. Illinois The fields along the southeast end of the LaSalle anticline had their peak of 33,686,000 bbl. in 1908. In 1932, with a 25 per cent restriction for 355 months, these fields produced 4,661,000 bb1.l There were 52 new completions (most of them in old territory) and of these 33 were dry, 8 were gas, and 11 were oil wells. The new oil wells had a total initial of 102 bbl., or an average of 9.3 bbl. per well. Nineteen of the new producers were in Crawford County. There were about 200 wells abandoned in the old southeast fields in 1932 as compared to 210 in 1931. The greatest number, 86, were in Lawrence County. To the end of 1932, the four major counties—Clark, Crawford, Lawrence and Wabash—had produced almost 394,000,000 bbl. from 92,160 acres. Better than one-half of this was produced in Lawrence County from 26,240 acres. The Dupo area of Sinclair County had no additions to production although four wells were drilled. On the Jacksonville structure in Morgan County, six gas wells with an average depth of 300 ft. were drilled to sands in the base of the Pennsylvanian. They produced an open-flow total initial of 2,000,000 cu. ft. This gas will be developed further to supply a local market.

Jan 1, 1933

Meeting of Mar. 26, 1915.-The following Committee on Nominations was appointed: Fred W. Bradley, Chairman; James F. Kemp, Past President; Frank M. Smith, Chairman Montana Section; R. C. Gemmell, Chairman Utah Section; Frank A. Ross, Chairman Columbia Section; Louis S. Cates, Arthur Thacher. The Committee on Precious and Base Metals and the Committee on . Coal and Coke were appointed, the personnel of which is shown in another part of this Bulletin. The President was authorized to appoint a Committee on Welfare with J. Parke Channing as Chairman. W. P. Cutter, Librarian of the United Engineering Societies' Library, was appointed a representative of the Institute on-the Committee oh Classification of Engineering Knowledge to co-operate with similar committees of other engineering societies. A vote of thanks was extended-to Edward B. Sturgis for his excellent work in arranging for the Annual Dinner. in February, of this year. The suns of $57.30 was appropriated to the New' York Section. It was resolved that in response to the courteous invitation from 36 members of the Institute in Arizona and the neighborhood, the 1916 summer meeting of the Institute be held in Arizona.

Jan 5, 1915

THERE have been two important accomplishments of the Truman administration; the Hoover Commission report on inefficiency and waste in government and the report of the Paley Commission on the natural resources of the United States. Both reports are in the interest of the American people and should transcend the boundaries of political parties. Both reports are starting points for the formulation of policies which must be continuously revised to meet changing conditions. Regardless of the outcome of the election the principles embodied in these two great documents must be kept alive. The Paley report is right in our own bailiwick of mineral raw materials and it behooves us to study it carefully as our responsibility to posterity. To those in the mining industry who have limited their field of observation to moving rock or to metal prices it may come as a surprise that our production of such staples as copper, lead, and zinc has fallen behind increased requirements to the point that substantial tonnages must be imported. Iron ore is next on the list and everybody knows that such metals as tin, tungsten, chromium, manganese, nickel, and cobalt are imported almost exclusively. The crisis in raw materials pointed up by the Paley report has been reported annually by Elmer Pehrson and others to small gatherings at the Mineral Economics Division sessions at the Annual Meeting for as long as we can remember. In September 1949, the United Nations Economic and Social Council held an international resource conference at Lake Success which disclosed these same grave conclusions: - Consumption of raw materials is multiplying at an alarming rate, faster than discoveries or replacements are being made. - Production has been wasteful and utilization lavishly beyond enginee¬ing and practical requirements. - Industrialized nations are depleted and many raw materials consumed by industry are not found in the industrialized countries. - Nations formerly exporters of raw materials are increasingly building their own consuming industries. - Political forces in the world are limiting access to raw materials. The Paley Commission selecting the quarter century, 1950 to 1975, to project raw material requirements for the United States, pointed out obstacles to meeting these requirements, and made recommendations for procurement. It is not important that we disagree that cobalt consumption will reach 344 pct of present, or fluorspar 187 pct when iron and ferroalloys are only expected to increase 75 pct. What is important it that the fabulous appetite of the United States for mineral raw materials has consumed more since World War I than was consumed by the entire world in all recorded history prior to 1914. And, unless the people of the United States are satisfied to remain at their present standard of living (which is unthinkable) this consumption is correctly plotted by the Paley Commission as continuing to expand. If the U. S. is to continue on a course of progress, it must procure raw materials wherever it can at the lowest possible cost. Natural resources are clearly an area in which the broadest cooperation between industry and government must exist to achieve efficient exploitation, economic consumption, and expansion of sources of supply. The message of the Paley report requires action comparable to that of the North Atlantic Pact. Its implication is as significant as military preparedness. It is a world problem. It is a mining engineering problem. Don't let it die!

Jan 1, 1952

By George C. Coupland

Ecstall Mining Limited, a wholly owned subsidiary of Texas Gulf Sulphur Company, is the owner and operator of the Kidd Creek Mine including the concentrator complex located near Timmins, Ontario. Canada, approximately 450 miles north of Toronto. The mine, concentrator and Timmins form a triangular arrangement with a 17-mile rail link connecting the mine and concentrator and both of these facilities 18 and 14 miles respectively by road from Timmins. A core drilling program in the spring of 1964 established the presence of a large massive sulphide orebody which was to become the Kidd Creek Mine. Texas Gulf Sulphur had been conducting an intensive search for base metal in various parts of Northern Ontario and Quebec since 1957. Of several thousand anomalies detected in airborne electromagnetic surveys, several hundred warranted ground inspection, but only one of more than sixty drilled became a commercial orebody, the Kidd Creek Mine. The geophysical exploration work has been well covered in a paper written and presented by Van Donohoo, presently a Vice-President of T.G.S., at the American Mining Congress in San Francisco in October 1969. GEOLOGY The orebody lies within a series of overturned rhyolitic flows and pyroelastics with a major peridotite intrusive to the east. The hangingwall and footwall are composed chiefly of intermediate volcanics, andesite and dacite. The southern end of the orebody appears to terminate abruptly against greywacke while the north end is bifurcated and the structure obscured.

Jan 1, 1970

By A. J. Terrones

THE classical papers on contact metasomatic deposits by Lindgren on the Clifton-Morenci district,' by Barrell on Marysville, Mont.,' and by Gold-schmitt on the Oslo district, Norway,' laid the foundation for understanding of the importance of separating the metamorphic process from the subsequent metasomatic stage. Knopf' made a big step forward by recognizing that sulfide ore minerals are invariably younger than silicates and by further stressing the importance of structural control" in ore finding. Some years later Harrison Schmitt" fought the idea that contact metasomatic deposits are erratic, irregular, bunchy, economically marginal, and of small size, concluding that these descriptions have little factual basis. He emphasized the importance of detail mapping and careful geological study as fundamental requirements for a better understanding of these deposits. This article presents a comparative description of the structural features at the Magistral, Antamina, Morococha, Vilca, Ferrobamba, Katanga (Quibio), Tintaya, and Huarca contact deposits (Fig. 1). Further, it will describe how these structural features controlled the emplacement of the intrusives, their shape, distribution of metamorphic and metasomatic halos, and sulfide deposition in post-skarn structural channelways. Finally, the modifications introduced by a superimposed hydrothermal stage recognized at some localities will be discussed. Primary exploration and careful sampling of recognized structural targets were instrumental in outlining the copper ore potential at the Antamina and Tintaya districts, thus proving the benefits and reward of careful geological examinations in this type of deposit. The Magistral District: This district lies in the Province of Pallasca, Department of Ancash, in northern Peru, at 8o 16' S and 77" 47' W. High to medium grade copper orebodies in garnetite, bordering a quartz monzonite stock, are exposed at the bottom of a glaciated valley in the western slope of the Andes at 4250 m (14,000 ft)* elevation.

Jan 1, 1959

By Richards J. W.

J.W. RICHARDS, South Bethlehem, Pa. (communication to the Secretary?).-Mr. Howland's paper, data and conclusions have interested me intensely, and have led me to study carefully the record-of his 26 furnaces therein given. Mr. Howland is undoubtedly right in his conclusion that when expressing the amount of carbon burned at the tuyères in percentage of the total

Jan 1, 1917

By Shiou-Chuan Sun

THE fact that coals of different ranks and even of the same rank differ greatly in their amenability to froth flotation is well known. In recognition of the need for an explanation of this phenomenon, two hypotheses have been suggested. Wilkins1 reported that the floatability of coals increased with an increase of the carbon content or rank. This postulate is handicapped by the fact that bituminous coals that possess moderate carbon contents are actually more floatable than anthracite coals that have high carbon contents, as shown in columns 6 and 9 of Table I. Taggart and his associates' implied that the difference of floatability between bituminous and anthracite coal was caused by the variation of carbon-hydrogen ratio. This is not applicable to the relative floatability of other coals and carbons. For example, column 11 of Table I shows that the carbon-hydrogen ratios of low-floating lignitic coal and non-floating animal charcoal are not only smaller than the moderate-floating anthracite coal, but are also similar to the high-floating bituminous coal. Furthermore, according to this hypothesis, high temperature coke-A (464), Ceylon graphite (1238), and lamp-black (357), all possessing extremely high carbon-hydrogen ratios, should be less floatable than other substances having much lower carbon- hydrogen ratios such as high volatile-B bituminous coal (11.9 to 22), anthracite coal (35.7 to 60.5), lignitic coal (15.6 to 33.6), and charcoal (13 to 26.2). However the former group is actually more floatable than the latter group.

Jan 1, 1954

By Frances H. Clark

IN a concern with the varied interests of the Western Union Telegraph Co., where practically all types of metals, both ferrous and nonferrous, are utilized, many types of failures of materials occur. These have to do not only with outside plant construction, such as corrosion and fatigue of line wire and cable, but also with inside plant equipment operating at such high speeds that rapid deterioration of metal. parts due to fatigue and wear results. Both corrosion and fatigue affect the life of copper wire so its normal life in any particular locality is largely dependent on the atmospheric conditions. Tensions vary widely owing to changes in temperature and ice and wind loadings and the wire is Subject to a great range of vibration caused by wind gusts aril vibration front trains or other heavy vehicles transmitted through the earth. High frequency low-amplitude vibrations are sometimes audible as singing in the wire. The other extreme is the vertical slashing or dancing of the wire observed during severe storms where amplitudes of 9, ft. or more at low frequencies have been observed.

Jan 1, 1942

By H. B. Pulsifer

ONE of the most common basic open-hearth furnace products is a simple carbon steel with a carbon range from 0.05 to 0.15 per cent. The material is widely used for sheets, tubes, bars, wire and the innumerable special objects of secondary fabrication. The properties of the material vary over wide ranges, depending on the more exact composition and details of manufacture or treatment that affect its structure. The present paper is a review of those properties and structures that have been found by studying this steel as used in the cap screw industry. At first glance this might be thought a narrow application of the steel, but, since the industry uses the material in the cold-worked, annealed and heat-treated conditions, the title of the paper may be excused for its comprehensiveness. Yet, in studying the wide ranges of properties and structures that preclude a more specific title, there can be no suggestion of completeness or finality. Even a summary of a few years' work is no more than a preliminary survey of a field that will be fertile in scientific data and industrial products for many years to come. An outline of the structures will be given first, then a list of the previous contributions that are at hand and finally some details of the work and related problems, especially concerning this low-carbon steel in the surface-hardened condition.

Jan 1, 1931

By J. F. Butler, H. W. Paxton

The vapor pressures of manganese in equilibrium with several alloys in the iron-manganese-carbon system between 1200° and 1275°K have been measured using the Knudsen effusion technique in conjunction with a vacuum microbalance. The effect of orifice area of the effusion cell upon the measured pressure has been determined. The binary iron-manganese system shows small negative departures from ideality, and the system of mixed carbides, (Fe, Mn)7C3, in equilibrium with graphite behaves ideally. THIS work is a continuation of the investigations in which the Knudsen effusion method has been used to determine thermodynamic activities in systems and at temperatures of interest to metallurgists. In a previous publication,' the free energy of formation of Mn7C3 was determined and some preliminary work on the solution behavior of this carbide with the hypothetical "Fe7C3" was reported. The present work deals with this latter topic and also includes data on the binary ir-on-manganese system. EXPERIMENTAL METHOD The Knudsen effusion method was used to measure the vapor pressure of manganese in both the alloy and carbide sections of this investigation. This dynamic method of vapor pressure measurement presents a problem when studying solid alloy systems in which one of the components has a much larger vapor pressure than the others. Over-all depletion of the alloy in the most volatile component will occur during evaporation so that the pressure of that component will decrease. Even more serious than the over-all concentration change is the surface depletion of volatile component in the alloy brought about by the slow rate of diffusion of this component from the interior to the surface of the solid particle. Since knowledge of this surface composition is necessary in order to relate it to the activity determined through the measurements, changes in surface composition from the analyzed bulk composition are to be avoided in dynamic vapor pressure studies of solid alloys. The system under investigation in this study presents the problem of surface depletion of manganese since its pressure at 1230°K is 105greater than iron and 1020 greater than carbon. Since the existence of a volatile manganese carbide had been ruled out previously,' the high manganese pressure relative to iron and carbon insured that the only species leaving the effusion cell was manganese. Therefore, the effusing species required no analysis so that the manganese pressure was determined directly from the weight loss of the effusion cell. In order to detect small weight losses near the beginning of effusion, a vacuum microbalance was used to weigh the cell continually. These initial weight loss data allowed the rate of manganese effusion to be determined before the surface of the alloy became depleted in manganese. The apparatus used in this investigation is shown in Fig. 1. Temperature was measured using chro-

Jan 1, 1962

By C. E. Van Orstrand

An intrusive body is a mass of igneous rock that has migrated upward, presumably from great depths. Great variations in form, composition and depth of burial occur. It is not proposed in this paper to go into all of the details of the problem. Instead, it mill be assumed here that the intrusive has the form and characteristics represented in Fig. I. According to W. 11. Emmons minerals are not deposited in appreciable quantities below the "dead line." Important amounts of ores of virtually all metals may be found around summit cupolas, but only gold, copper and zinc (in limited quantities) are usually associated with trough cupolas. Most students of ore deposits agree that temperature changes are largely instrumental in precipitating many ores in the "hood" and that the difference in temperature between the intrusive and that of the country rock may be the chief factor in determining the mineralogy of a deposit. A problem then of some interest is to correlate the principal physical features of the intrusive with the phenomena of heat conduction as evidenced by the cooling curves and the isothermal surfaces. Mathematical Theory In order to show the possible application of heat conduction to the interpretation of the processes of metalliferous deposition associated with intrusives, it will be as- sumed that the intrusive is a large par-allelopiped of dimensions, 2l, 2m, 2n. The equation that represents the flow of heat from the parallelopiped into country rock (v = o, 1 = o), which has the same thermal properties as the intrusive, is2,3 l-x v I FT 2 [2 2 — l-x m — y — m — y n — z In this equation, the origin, x = o, y = o, z = o, is at the center of the parallelopiped. v = temperature at point x, y, z, time 1. v, = initial temperature throughout the intrusive, 1 = o. k = coefficient of thermal diffusivity. a, ß, y are variables of integration. Put n = m in Eq. I, and we have v I [2/5 [2I-x 2 — l-x m — y 2 2 2 kt 2 20xt e-a2da ebrdß

Jan 1, 1946

By C. E. Van Orstrand

An intrusive body is a mass of igneous rock that has migrated upward, presumably from great depths. Great variations in form, composition and depth of burial occur. It is not proposed in this paper to go into all of the details of the problem. Instead, it mill be assumed here that the intrusive has the form and characteristics represented in Fig. I. According to W. 11. Emmons minerals are not deposited in appreciable quantities below the "dead line." Important amounts of ores of virtually all metals may be found around summit cupolas, but only gold, copper and zinc (in limited quantities) are usually associated with trough cupolas. Most students of ore deposits agree that temperature changes are largely instrumental in precipitating many ores in the "hood" and that the difference in temperature between the intrusive and that of the country rock may be the chief factor in determining the mineralogy of a deposit. A problem then of some interest is to correlate the principal physical features of the intrusive with the phenomena of heat conduction as evidenced by the cooling curves and the isothermal surfaces. Mathematical Theory In order to show the possible application of heat conduction to the interpretation of the processes of metalliferous deposition associated with intrusives, it will be as- sumed that the intrusive is a large par-allelopiped of dimensions, 2l, 2m, 2n. The equation that represents the flow of heat from the parallelopiped into country rock (v = o, 1 = o), which has the same thermal properties as the intrusive, is2,3 l-x v I FT 2 [2 2 — l-x m — y — m — y n — z In this equation, the origin, x = o, y = o, z = o, is at the center of the parallelopiped. v = temperature at point x, y, z, time 1. v, = initial temperature throughout the intrusive, 1 = o. k = coefficient of thermal diffusivity. a, ß, y are variables of integration. Put n = m in Eq. I, and we have v I [2/5 [2I-x 2 — l-x m — y 2 2 2 kt 2 20xt e-a2da ebrdß

Jan 1, 1946

By D. W. Levinson, L. E. Tanner

DURING the course of an investigation of the zirconium-iron-tin system the zirconium-iron system was reexamined up to 55 pct* Fe. The alloys pre- visible melting3 and X-ray diffraction studies were made of samples of the alloys. The ferromagnetic properties of ZrFe2were determined by Professor P. W. Selwood* using a modified Faraday balance.4 The zirconium-rich portion of the phase diagram is presented in Fig. 1 and compared with the work of Hayes et al.1 The maximum solubility of iron in ß is somewhat decreased while the eutectic temperature is raised. There seemed to be no change in the eutectic composition of 16 pct Fe. Since the base material was so low in iron content, it was possible to establish the maximum solubility in a between 0.017 and 0.025 pct Fe at the eutectoid temperature. The observation of fine ZrFe, particles in the micro structure of a specimen of 0.012 pct Fe alloy quenched from 700°C indicated that the solubility drops below this composition at 700° C and lower. Further study was made of the intermediate phase ZrFe2. wallbaum5 identified the compound initially as ZrFe2 with a C 15 (MgCu2) structure, placing it at 55 pct Fe stoichiometrically. Hayes et al.1 believed they found the phase at about 47.2 pct Fe and called it Zr2Fe3 but reverted to ZrFe, in the discussion of their paper.6 Jordan and Duwez7 confirmed Wallbaum's work as well as finding the same single-phase structure to about 62.3 pct Fe or Zr0-61 Fe2-18. In order to establish the ternary phase relations in the zirconium-iron-tin systema the exact position of this phase had to be known. This was accomplished by X-ray diffraction, visible melting, and metallographic techniques. Elliott8 obtained a single-phase ZrFe2 X-ray diffraction pattern from an alloy of about 55 pct Fe. This was confirmed in the present study with an alloy of 54.81 pct Fe. However, extra lines (attributable to a or ß zirconium) were found in diffraction patterns of the 47.42 and 49.83 pct Fe alloys. The melting characteristics of these same alloys were studied by suspending 47.42, 49.83, and 54.81 pct

Jan 1, 1960

By F. F. Skiba, P. J. Root

A mathematical model has been used to investigate crossflow effects in a stratified reservoir during an idealized displacement process. A process in which one incompressible fluid displaces completely another incompressible fluid of the same density and viscosity was considered. The reservoir was assumed to be composed of homogeneous layers which are discrete but interconnected. Approximate five-spot flow geometry was simulated by arranging two pie-shaped cylindrical (two-dimensional) wedges in series. Some of the common production methods rely, for their effectiveness, on the fact that the formation consists of isolated strata. This is particularly true of selective plugging and single-zone production-injection methods. The effectiveness of these techniques for several cases in which adjacent strata are in communication has been evaluated. The usual production-injection schemes for fluid injection processes involve using the same completion interval in both the production and the injection wells. The efficiency of this, as well as alternative productioz-injection procedures has been examined for some cases involving communicating strata. INTRODUCTION The performance of many fluid injection projects is marred by early breakthrough and by production of a high percentage of the displacing phase after breakthrough. This channeling effect, if it occurs in reservoirs which have large permeability variations, is often explained on the basis of a model composed of discrete, isolated strata. Corrective or preventive measures based on this same model are also common. The behavior of stratified models has been the subject of considerable study. An excellent review of the early literature was given by Seba.1 Studies of the depletion performance have since been made for continuous, unrestricted communication between strata2-4 and for production from one permeable bed in continuous but restricted communication with an adjacent permeable bed.5,6 Model studies of displacement processes in stratified systems with crossflow also have been reprted.7-12 Finally, methods which account for crossflow have been developed for computing displacement behavior in stratified systems.13,14 Most methods for controlling or preventing channeling involve some change in the interval open to production and/or injection. Although many variations of the selective completion problem have been studied in regard to the depletion of a reservoir, little attention has been given to the behavior of a displacement process under similar conditions. Sebal used a resistance network model to study the performance of a process in which one incompressible fluid displaces an identical fluid from a linear, stratified reservoir. He investigated the possibility of improving the vertical coverage by limiting the completion interval of the production well. This investigation deals with techniques in which selective completion of the production and/or the injection wells is used in an attempt to control channeling. At one extreme, selective plugging and single-zone isolation (assuming perfect execution) should be successful if the reservoir is actually made up of independent strata. At the other extreme, they can hardly be expected to be successful if the channeling is caused by a mechanism in which stratification effects are negligible even though there are extreme variations in the formation permeability and/or the injectivity profile of the wells is not uniform. By contrast, it is difficult to anticipate the effect that the amount of communication between the beds of a stratified system will have on the efficiency of selective completion techniques. The objective of this study is the quantitative determination of the effect of communication on the behavior of some particular stratified systems which will at least lead to qualitative conclusions.

Jan 1, 1966

By J. P. Zannaras

Referring to the article by R. J. Charles and P. L. de Bruyn, let us assume that W = weight of glass bar; P = weight of hammer; e = total deformation; K = unit of deformation; K = potential stress energy; E = modulus of elasticity; L = length of the bar; 7 = coefficient of inertia; h = height, ft; V = velocity, fps; and a = cross section area. The portion of kinetic energy which is effective in producing stress energy in a fixed bar struck horizontally is given by the formula" 1 + 1/3 W/P K =1+1/3w/p/(1+1/2w/p)2 P.V2/2g = Ph where 1 + 1/3 W/P ? (1 + 3W/P/(1=1/2w/p)2 [8] Putting e e = W/P =------------ From the above equation it can be seen that the maximum transfer of kinetic energy to stress energy is when e = 0 or W/P = 0 which indicates that the weight of the hammer must be very large as compared with the weight of the impacted rod. Eq. 8 diametrically opposes the conclusions reached by the authors of this article. In fact, if their suggestions were followed to the extreme when e = co when P = 0, there would be no transfer of kinetic energy to stress energy at all, as 7, becomes zero. Eq. 8 presumes that the velocity with which the stress is propagated through the bar is infinite, whereas the authors claim that the compression waves reflected are reaching the struck end of the bar prior to the complete transfer of the kinetic energy to cause such modification of the conditions there as to make them reach the reverse conclusions demonstrated by the above formula. That such interference exists is unquestionably demonstrated by the authors and others. However, if my observations are correct, such interference for this specific experiment and also for practical comminu- tion is insignificant, and the conclusions of the authors are in error and must be reversed to comply with Eq. 8. Eq. 5, w. = AE 2/2, given by the authors on page 51, is derived from the following equation (Eq. 9): K = 1/2Pe, where P = Sa, S = ?E, e = EL, and L = 1. The above formula, Eq. 9, cannot be applied in this case. This formula is applicable for static loads where the load increases from zero up to its final value, P, in such a way that the deformation at different instants is proportional to the loads acting at those instants and actually represents the area of a right triangle in the strain load diagram of base e and height P. The typical photographs shown in Figs. 3 and 4 represent the familiar strain load diagrams, and since the line of the wave marks the existence and intensity of the strain with the unquestionable conclusion that such strain has been caused by the action of a load acting continuously all along the wave until it reached the horizontal axis, the work stored at this point is represented by the area under the wave line and the horizontal axis and not by the area of the fictitious triangle given by the authors. Then if this is correct, even visual estimation of these areas at gage stations given in the typical photographs of Figs. 3 and 4 suffice to contradict the authors' calculation given in Figs. 6a and 6b and Figs. 7a and 7b. The typical photographs presented by Charles and de Bruyn show a considerable variation of the intensity of the strain at different stations but very small variation of areas which actually represent the stress energy at the corresponding stations. And, apparently, by squaring the small quantities, the authors magnified their error tenfold. J. M. Frankland's paperV iscusses the relative strain intensity and not the total energy for different types of impact loading. He states in his paper, "The reader is explicitly warned not to confuse the results in this report with those obtained when the load is applied by a blow as from a hammer. In this case the peak load rises to very large but mostly unknown values. The accompanying large deflections and stresses are the result of high values of P, not of the dynamic load factor n. According to Frankland "the dynamic load factor" is the numerical maximum of the response factor. It therefore appears that the authors followed the same procedure in obtaining the relative strain energy ab-

Jan 1, 1957

By David Cole

THE appearance of the Wilfley table in 1897 marked an epoch in the art of concentration of ores. The table has merited and received an almost unprecedented measure of public approval, lasting through its whole patent life. It has been very little improved in itself, or improved upon by competitors. The new machines bidding for popular favor have been of the Wilfley family, but without ability to do markedly better work than the parent m:-chine, or to (to more work except by the use of superimposed decks, the latter having obvious disadvantages. FIG. 1.-The- Butchart RIFFLE System. During the past three years there has been developed at Morenci a new type or arrangement of riffles applicable to the Wilfley type of concentrating table which corrects many of the objectionable features or limitations of the older system and obviates most of the difficulties encountered with it, particularly when handling ores having a low ratio of concentration. The new type is known as the Butchart1 riffle system, and its general arrangement is shown in Figs. 1 and 2.

Jan 2, 1915

By Sumner M. Anderson

Any discussion of outside support to Latin American mineral industries must concede at once the pre-eminent role of U. S. industry and business. American capital has developed the great copper resources of Chile and Peru, the lead-zinc of Peru and Mexico, the bauxite of Surinam and Jamaica, the petroleum and iron ore of Venezuela. American consumers have provided the market for their products. U. S. companies operating south of the border have trained Latin American geologists, engineers, chemists, and skilled labor—including metal, mineral, and fuel technicians—to new and greater competence. The industrial demands of World War II drastically altered world economics and concepts of U. S. foreign mineral requirements. In this country discovery of vital mineral resources fell far behind the alarming depletion rates, and there was new appreciation of the actual and potential importance of the world's less extensively explored areas. During the war and afterward, the task of supplying the nation's mineral requirements became greater than private industry could carry alone, and the Government assumed a position of continuing support. In Latin America, as elsewhere, this support applies in three categories: banking, procurement, and technical assistance. The first two are now generally accepted as necessary Government functions; the third has often been misunderstood and misinterpreted, although it has given rise to legitimate controversy. There have been major accomplishments in all three categories, as well as some errors of judgment. Since the beginning of World War 11, U. S. Government financing, procurement, and technical assistance have been applied on a large scale to a wide range of commodities and services throughout the free world. The present discussion—under the separate headings mentioned—will concern only the support related to a single industrial group in a single geographic area. During the War Federal banking was conducted on an emergency scale by temporary agencies created to meet the abnormal circumstances. Unfortunately, there are no readily available data on these activities that would permit evaluating loans and credits extended for mineral projects in Latin America. The only agency operating in this field since World War II is the Export-Import Bank, under its own authority and to some extent from credits authorized by the Office of Defense Mobilization. The Bank can offer more capital—on more favorable terms—than is available from most Latin American banks, and its staff of engineers evidently can appraise loan applications more favorably than commercial banks in this country are willing to do. The risks seem to be justified, as defaults have been well under 1 pct of total loans. From V-J day 1945 to the end of 1957, mineral loans to Latin America have been authorized for projects totaling $541.63 million in eight countries. In order of magnitude of credits, they have been made to Brazil, Peru, Chile, Mexico, Argentina, Venezuela, Guatemala, and Bolivia. In order of magnitude by industries. they are for development and expansion of steel mills, copper, manganese, nitrate plants, iron ore, zinc plants, sulfur plants, cement plants, tungsten, coal, and lead. Loan Distribution: By far the largest loans have been $307.9 million for iron and steel projects in Brazil, Chile, Mexico, Argentina, and Peru: $100.4 for developing the great low-grade copper deposits of southern Peru; and $55.3 million for developing manganese deposits in the Territory of Amapa, Brazil. Others range from $20.8 million for a zinc smelter in central Peru to $19 thousand for iron-mine trucking equipment in Chile. It has been noted that 59 pct of the loans have been to foreign companies, 14 pct to companies of mixed foreign and American capital, and 27 pct to American mining companies. About 40 pct of the total authorizations has been disbursed so far. In addition to these amounts, the Strategic Materials Division of the Economic Cooperation Admin-

Jan 1, 1959

At the meeting of the Board of Directors of the Institute on Jan. 26, 1917, the following actions were taken: Messrs. A. C. Clark, Lawrence Addicks and G. D. Van Arsdale were appointed Tellers to count ballots for Officers and Directors. Messrs. T. T. Read, V. S. Harper, and. E. J. Hall were appointed Tellers to count ballots on revised spelling. The Finance Committee's audit for the year 1916 was approved and ordered filed. The Report of the Finance Committee upon the method of raising this Institute's share of the deficit on the additions to the building was approved and accepted. Upon the recommendation of the Secretary, increases in the salaries of some of the employees were approved. The St. Louis Section received an appropriation of $200 for the year 1917. The Columbia Section received an appropriation of $150 for the year 1917. The Montana Section received an appropriation of $100 for the year 1917. The Colorado Section received an appropriation of $175 for the year 1917. The Utah Section received an appropriation of $125 for the year 1917. The Puget Sound Section received a set of Transactions in standard binding. The International Engineering Congress received a loan of $300 until the Congress can realize upon some of its assets.

Jan 3, 1917