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By HUGH E. McKinstry

OPENING the sessions of the Mining Geology Committee, the program on postwar mineral controls drew a larger attendance than any other session of the entire meeting. In view of its general interest, the papers of this session, or a substantial portion of them, are printed elsewhere in this issue. Whether control of mineral resources can help to promote peace, how controls could be applied and to whom, are questions so far-reaching that naturally no pat answer was agreed upon. In fact the discussion took on something of the flavor of a debate between those who favor strict control and those who felt that attempting to ration nations in peacetime would defeat its own ends. Discussion from the floor emphasized the difficulties in administering any international control and the $64 question, that no one cared to answer, asked by a courageous young lady who was induced to mount the rostrum for the purpose, was whether the United Nations should exchange mineral controllers to police each other.

Jan 1, 1944

By J. H. Scaff, H. C. Theuerer

Germanium may be reversibly converted from n to p type by heat treatment. Data for the conversion and the associated changes in resistreatment.tivity are given and the results are interpreted in terms of changes in the donor-acceptor balance. MEANS for controlling the electrical properties of germanium in a predictable manner are of interest because of the increasing utilization of this element as the semiconducting material in electrical devices. Since both the mechanism and the magnitude of the electrical conductivity depend upon the kind and quantity of impurities present, the conductivity usually is adjusted by first carefully purifying the germanium, and then, by standard alloying procedures, adding the elements desired. The elements usually added are from the third or fifth periodic groups depending upon whether p- or n-type germanium is desired. However, in the development of germanium rectifiers during the war, it was found that it was possible also to modify reversibly the conductivity of germanium and even to produce conversion from n to p type by heat treatment.1,5 Since then a detailed study of this effect has been made. The data are presented in this paper and an explanation is offered for the effects observed. Preparation and Experimental Procedure The method used in preparing the germanium ingots for this investigation has been previously described.' The method consists essentially of (1) reduction of GeO2* and (2) preparation of a 50-g ingot from the reduced material. Graphite containers are used in both steps. In the first step the GeO2 is reduced in hydrogen at 650 °C to form a sponge germanium which, to assure complete reduction and to obtain massive materials, is fused subsequently in the reduction furnace by gradually raising the temperature to 1000°C. The button of germanium thus obtained corresponds to a yield of 99.8 pct. The final ingot is prepared by fusion of the germanium button in a helium atmosphere. A cylindrical crucible in a vertical silica tube furnace is employed and the crucible is heated by an external induction coil. The ingot is solidified from the bottom upward by raising the induction coil at a constant rate with power to the coil kept at a fixed value. In such ingots, segregation is normal and most of the impurities are concentrated in the last region of the ingot to freeze. It follows then that the major portion of the ingot is purer than it would have been if freezing had occurred in a random fashion. Moreover the orderly advance of the freezing surface during solidification establishes in the ingot a succession of surfaces of constant composition, if it is assumed that the liquid is homogeneous and that diffusion in the solid is negligible. Therefore, some information on the distribution of impurities in the ingot may be acquired by determining the shape of the solid-liquid interface at different stages of solidification. This is of importance because the concentration of impurities will be seen to affect the response of germanium to heat treatment. Such information is difficult to acquire by direct means, for the impurities responsible for the electrical properties of germanium prepared in this way are present

Jan 1, 1952

By S. F. Reiter, W. R. Hibbard

A survey of the effect of heat treatment on the room temperature hardness of Fe-Mo alloys has been made. Constant strain rate tensile tests were performed between room temperature and 1800°F. These data were analyzed to determine the effect of temperature and composition on the strain hardening coefficient and strain rate sensitivity. Constant load creep-rupture tests were made on these alloys and the results related to composition and structure. A relation between the high temperature strength of the precipitation hardened alloys and the volume of precipitate has been observed. IN view of the extensive use of ferritic materials at elevated temperatures, it is surprising to note the limited amount of information relating the variables of plastic deformation, i.e., composition, structure, temperature, stress, strain, and strain rate. Hollomon and Lubahn' showed how the several variables of plastic flow might be treated analytically. No data were available on carbon-free iron and its alloys in a form suitable for this analysis. Several German investigations2-" constitute most of the experimental work relating high temperature properties to the constitution of these types of materials. In order to obtain new data, the iron-rich alloys of the Fe-Mo system were selected for detailed investigation for the following reasons: 1—Some of the important effects of molybdenum on the mechanical properties of iron have already been studied.' , 821 2—By suitable heat treatment of selected alloys, it is possible to study strengthening effects of four types: AT -a transformation, B—substitutional, C—precipitation, and D—dispersion of hard inter-metallic compound. Materials and Treatment Four-pound ingots were vacuum cast, employing the same melting schedule previously used.? The raw materials were electrolytic iron and lamp-grade molybdenum. The ingots were forged to l/z in. sq. rod and one portion swaged to 0.350 in. diam rod for the production of 1 15/16 in. long button-head specimens. The button-head specimen blanks were solution treated for 16 hr at 2100°F in hydrogen of —70°C dewpoint and then water quenched. They were subsequently plunge ground to the standard 0.160 in. diam test bar. Micrographs of the solution treated alloys are given in Figs. la through Id. The higher molybdenum alloys contained large equiaxed ferrite crystals similar to those in Fig. Id. A portion of the % in. rod was hot rolled to 0.100 in., sandblasted, and cold rolled to 0.020 in. Strip tensile specimens having a 0.020x0.200 in. cross-section and a 2.25 in. gage length were machined from the sheet. The alloys containing molybdenum were subsequently annealed 1 hr at 1560°F. The iron strip was annealed 4 hr at 1300°F in wet hydrogen. The resultant structures are shown in Fig. 2a through h. The ASTM grain sizes were 1 to 3 as solution heat treated or 3 to 4 as annealed. The chemical analyses of the alloys are given in Table I. Carbon contents were obtained after the heat treatments in hydrogen. Alloy 15.9 pct Mo was tested as a cast alloy.'

Jan 1, 1956

By AIME AIME

PERHAPS the outstanding characteristic of the newly elected President of the Institute is his rare ability to set aside nonessentials, and pick out the few basic elements on which a valid conclusion on any question can be drawn. This holds whether he is appraising a mining enterprise, selecting a man for an important position, deciding whether to buy or sell a bond, or choosing the best method for mining a huge body of ore. For example, he has pointed out that the two primary factors that make for success in a copper-mining venture are a large reserve of reasonably good ore and competent management. Usually the first is not as difficult to gauge accurately as the second. In a big enterprise the quality of the management

Jan 1, 1939

By Walter V. Knopp, Laurence Delisle

INTRODUCTION THE aim of this work was the preparation of nickel-steels from elemental metal powders by powder metallurgy techniques. It was known that plain carbon steels could be made from a mixture of iron powder and graphite and that the effect of carbon on iron in powder form was of the same nature as that produced in fusion metallurgy. The problem in making nickel steels from elemental powders consisted therefore in finding out whether sufficient diffusion of the nickel and other incidental metals normally present in such steels could be induced in the solid state to modify the properties of plain carbon steels made from powders and produce the beneficial effect of alloying. The composition selected originally was that of an S.A.E. 2330 steel. Metal powders, in the proportion corresponding to that composition, were mixed with graphite, pressed, and heated at different temperatures for different periods of time, to produce bonding of the metal particles and mutual diffusion of the various elements without melting. Temperatures up to 1325°C and sintering periods as long as 6 hr were first investigated because it was expected that such conditions would produce maximum diffusion with an accompanying improvement in the properties of the alloy. It was found that, although diffusion proceeded to a large extent under the conditions investigated, it would not be complete unless sintering were carried out at a high temperature for much longer than 6 hr. Relatively high temperatures and long sintering times are objectionable from a practical point of view, particularly when a low cost material is to be produced, because they necessitate the use of special, costly equipment. Work could be done to improve the diffusion of iron and nickel by changing conditions other than the sintering temperature and time, i.e., finer primary or alloy powders could be used. However, a marked change in the properties of the steel had been observed even with only partial diffusion. It was thought, therefore, that instead of trying to improve the diffusion, advantage might be taken of its incompleteness to produce a special structure consisting, in the unquenched condition, of a hard constituent, rich in nickel, dispersed in a tough pearlitic matrix. Steels with such a structure, not readily obtainable by fusion, should have desirable mechanical properties. Besides, it should be possible to prepare them from elemental powders under economical conditions. This latter alternative was therefore adopted for the second phase of this work. This report is divided into four parts: 1. General Procedure. 2. Effect of Sintering Temperature. 3. Effect of Varying the Nickel Content. 4. Effect of Alloying Elements. GENERAL PROCEDURE The general technique of cold pressing as used in powder metallurgy was applied.

Jan 1, 1948

By John S. Crandall

The mineral garnet, while ordinarily considered a semiprecious gem stone or a second-grade industrial gem, has also proved itself in the field of industrial abrasives. Its use is well known as a sand-paper grain, and as a sandblasting sand its qualities are rapidly becoming recognized in more and more industries. Production of garnet as an abrasive is confined chiefly to two areas in the United States, North Creek, N. Y., where the Barton Mines Corp. operates, and Emerald Creek, Benewah County, Idaho, where the Garnet Mines, Inc., and the Idaho Garnet Abrasive Co. with mills at Fernwood, Idaho, operate. This paper is confined to a discussion of production and marketing of garnet sand by Idaho Garnet Abrasive Co.

Jan 5, 1950

By E. P. McCurdy, William J. Tait, Allen E. Craig

The Circuitron herein described applies current from the classifier motor circuit and energy from the sound of grinding media to move an oscillating disc. The disc through a photoelectric cell controls the speed of the ore feeder and consequently the amount of ore delivered to the mill.

Jan 10, 1950

By A. J. Griest, P. D. Frost, J. R. Doig

During the past 5 years, research directed toward the development of titanium alloys having improved strength-ductility relationships and heat treatability has been carried out at Battelle for the U. S. Air Force.1"3 In the course of this work, a method of heat treating ß-stabilized titanium alloys was developed which produced a wide range of useful properties.4 The heat treatment consisted of two steps: a) solution treating at temperatures in the a-ß phase region, and b) overaging at a lower temperature in the range 800°to 1100°F. Corollary to the alloy development work, research was conducted on the mechanism of the heat-treatment reaction. The investigations of Frost and co-workers on isothermal transformation in Ti-Cr5 and Ti-Mn8 alloys disclosed the existence of the transition phase, w, during the course of the decomposition of metastable ß phase. Subsequent work at Battelle7,8 'and at Case Institute by Brotzen and co-workerss further clarified the nature of the decomposition process. Beta decomposition was found to proceed by the following series of reactions: 1 2 3 4 a + Ti, My (in eutectoid systems). ßo, ßr, and ßU refer to ß phase of original, enriched, and ultimate alloy contents, respectively. Omega is a transition phase having a complex structure. 10-13 Step 4, of course, occurs only in ß-eutectoid systems. This paper presents data correlating transformation behavior with mechanical properties for the following alloys: Ti-8Mn, Ti-8Mn-2A1, Ti-4Mn-4A1, Ti-6Al-4V, and Ti-4Fe. The isothermal decomposition of ß in titanium-manganese alloys of similar composition has been investigated by Frost and coworkers8 and the effect of various annealing treatments on alloys in this system has been studied by Holden, Ogden, and Jaffee.14 The compositions Ti-8Mn-2Al, Ti-4Mn-4A1, and Ti-6A1-4V, were studied in the present work in an effort to define more clearly the effect of aluminum on the response to solution and aging treatments. Ogden, Holden, and Jaffee15 have invesitgated the effect of aluminum on the response of a similar alloy (Ti-8.8Mn-2.46A1) to annealing treatments, and Luini and Lee16 have made an exploratory investigation of the heat-treatability of the Ti-4Mn-4Al alloy. The Ti-4Fe alloy was studied as an example of a moderate1y active eutectoid system. Holden, Ogden, and Jaffee 17 have studied Ti-Fe alloys and have presented some hardness data for aging at 400°C for alloys of Ti-2.56, 5.01, and 7.35 iron after quenching from the a-ß field (750°C). EXPERIMENTAL PROCEDURES The experimental procedures generally used in the precipitation-hardening study are outlined in the following sections. Departures from these techniques are noted in the discussions of the individual alloys. Table I presents the nominal and actual compositions of the alloys studied, together with the swaging and rolling temperatures. In all cases, these temperatures were in the a-ß field and the microstructures consisted of an equiaxed a-ß mixture. Melting and Fabrication—Except for the commer-

Jan 1, 1960

By G. R. Belton, Y. K. Rao

A galvanic cell, using liquid MgCl2 or MgC12-CaC12 mixtures as the electrolyte, has been used to determine activities in Mg-A1 liquid alloys between 700' and 880°C. The incovporation of a chlorine electrode in the cell also allowed measurements to be made of the standard free energy of formation of MgCl2(l). The results are shown to be in good agreement with thermo-chetrlical values from the literature, and this is taken as evidence that the small, known solubility of magnesium in iMgCl2 introduces no significant error in galcanic cell measurements. Within experimental error, the activity coefficients and relative partial molar enthalpies at 800°C are shown to be represented by the following "subregular" solution equations: logy~~ =-0.68(1 -xMgj3 log yAL =-1.02(1 - XMf + 0.68(1 - XMf H.M = -4400(1 - %)3 / cal Mg 7Ag' HZ =-6600(1 - xA1)' + 4400(1 - XMf cal SCHNEIDER and toll' have used a transpiration technique to measure the vapor pressures of magnesium over Mg-A1 alloys between 544" and 594°C. amsstad,' however, has since suggested that the extrapolation to zero flow rate, used by these authors in interpreting their apparent pressure vs flow rate data, gives unreliable results. Rogers, Tomlinson, and Richardson,3 in interpreting the results of solution equilibria between Mg-A1 alloys and liquid MgC12, also considered the measurements of Schneider and Stoll to be unreliable and preferred to derive activities for the alloys from the earlier boiling point determinations of ~eit~ebel~ and the partial molar heats recommended by Kubaschewski and ~atterall.~ These latter heats were based substantially on the early calorimetric work of Kawa-kami but, unfortunately, his work on other systems has sometimes been found to be inaccurate.7 Rogers et al., in the above-mentioned paper,3 tentatively concluded that the most likely species responsible for the limited solubility (0.3 mole pct at 800°C) of magnesium in MgC12 were Mg° (neutral) and Mg2++. Two more recent studies8,9 have supported Mg2++ as the soluble species. In the present study, activities in Mg-A1 alloys have been determined by means of a galvanic cell involving liquid MgCl2 or MgC12CaCl, mixtures as the electrolyte. Since the reactive nature of magnesium precluded simple Faraday yield experiments, a chlorine electrode was incorporated in the cell in order that the performance of the cell could be checked by measurements of the heat and free energy of formation of MgC12. This procedure was considered necessary since it has been suggested1' that the solubility of a metal in a molten salt might introduce electronic conductivity; also, previous determinations of the standard electrode potential for MgC12 differed by as much as 70 mv11-13 EXPERIMENTAL Materials. Analyses of the materials used in preparing the alloys and the electrolyte mixtures are presented in Table I. The alloys were prepared by induction melting weighed amounts of the metals in a graphite crucible held under an argon atmosphere. Pure anhydrous magnesium chloride was prepared by heating the mixture MgCl, . 6H20 +NH4C1(1:1) to 650°C, followed by melting under dry argon. The melting point of the dry MgC12 was found by differential thermal analysis to be 714.8oC, which compares well with the accepted value of 714C.14 This agreement was taken to be an indication of the high purity of the dried salt. Table I. Compositions of Materials, wt pn Impurity Mg Al MgCI2 CaCI, Ba - - 0.005 Ca - - 0.010 Cu 0.02 0.02 Fe - 0.10 0.001 0.010 Pb 0.01 - 0.001 0.005 Mn 0.15 0.001 Si - 0.10 Sr - - 0.005 MBSO* - 0.040 ARGON TUNGSTEN CHLORINE LEAD—411 11 II ALUMINA 'A I / ave GRAPHITE on irA~_ ( ^"l ROD MAGNESIUM S>ILICA~^ /, OR ALLOY-. I /A] ___________ -«^- _ ELECTROLYTE I y FRITTED DISCS Fig. l—Arrangement of chlorine and metal electrodes in electrolytic cell.

Jan 1, 1970

By Frank Schrader

J. DANA SPERR, Jerome, Ariz. (communication to the Secretary*).¬Very little accurate information has been published about this district. Most of the geological data appearing in the technical press are based on "careful observations" made from an auto stage and a casual glance through the U. S. Geological Survey Bulletins, No. 340 of 1908 or No. 397 of 1909, both by F. C. Schrader. Mr. Schrader's report is still the best publication on the district. A really careful study of this report will uncover only a very few statements which have since proven questionable. This is a remarkable record when it is considered that only a short time was spent by Mr. Schrader in the field and that there was very little development work done at that time. The mining world and especially Mohave County, Ariz., will feel a sense of gratitude to Mr. Schrader for revising his early report. on this

Jan 3, 1917

By Bradley Stoughton

AT THE meeting of the Board of Directors on May 20, the resignation of Bradley Stoughton as Secretary of the Institute was presented and regretfully accepted by the Board. The letter of resignation follows : Gentlemen: About two years ago, I indicated to the President and some members of the Board my belief that the office of Secretary of the Institute should not be a permanent one. It is my observation of events, not only in our own Institute, but also in several sister societies, that too long a tenure of office by the Secretary inevitably leads to a situation which is not good either for him or for the society. After submitting this in writing to the Directors on February 17, 1920, I was overpersuaded by members of the Board to defer resignation until a more convenient time for the

Jan 1, 1921

By T. D. Parris

Within a 30-mile radius of Sudbury, Ontario, the Ontario division of the International Nickel Co. of Canada, Ltd., operates nine underground mines and two open pits. Prior to 1966, ore removal from the underground workings was mainly by scraping, using 125-hp electric slushers in blasthole and caving mining, and 30-hp or less air-operated slushers for fill- method mining. The development and evaluation of low-profile, diesel-powered front-end loaders, designed specifically for underground operations, was followed with keen interest during the period 1964-1965.

Jan 6, 1969

By B. M. Larsen

Attempting to review the fundamental aspects of segregation in steel ingots of all types in a paper of reasonable length, we encounter two difficulties: (I) the fact that a large number of different physical and chemical effects are involved, and (2) rather incomplete and confusing evidence on certain aspects of detail and mechanism in the freezing process in which the segregation effect is involved. The best solution seemed to be to link together most of the underlying factors into a simplified theoretical picture that appears to the writer to explain most of the observed data, in the hope that this will serve as a reasonably good target for discussion and criticism. Segregation effects, especially in steel ingots or castings, are often divided into " microscopic" and "macroscopic," depending on whether the variations in concentration of solutes or dissolved elements in the iron occur as: (I) a periodic variation over the small distances between the nuclei and the surfaces of the primary grains, or (2) as a larger scale effect involving concentration gradients over distances of the order of several inches, more or less. The reason for this somewhat artificial division is, of course, that it is only the macroscopic scale effect that has much practical importance. About the only effect of practical importance that results from microscopic segregation is the banded structure often left in rolled sections, and even this is relatively harmless in most cases. However, the causes of microscopic segregation also untlerly the larger scale effect, so we must first consider matters such as the formation and growth of crystal nuclei, selective freezing and diffusion, and others that are fundamental to all sepregation effects. Undercooling and Nuclei Formation It is probable that although the degree of undercooling is small in iron, as in metals in general, a certain amount of it takes place, and also that the number of crystal nuclei increases very rapidly with increased undercooling below the liquidus temperature. In practical terms this means that the nuclei number illcreases very rapidly with increased cooling or freezing rate, thus being dependent on the rate of heat flow out from the zone of crystallization. Temperature Gradients and Heat Dissipation during Freezing Each pound of steel evolves about 100 B.t.u. when freezing. In addition to this, the temperature gradient in the solidified portion (required to dissipate the heat as freezing progresses into the axis) necessitates a loss of heat required to cool the solid metal below its freezing range, which is equivalent to an amount of not so much less in magnitude. In a 5-ton ingot, the total would include about one million B.t.u. for freezing alone and about 0.4 to 0.5 million B.t.u. for the gradient, up to the end of the freezing period. Thus the rate of freezing depends primarily on the rate of heat dissipation. In the ordinary ingot shapes, the axial rate of growth of the solid

Jan 1, 1945

By Rebecca Mae Summer

Increasing urbanization and industrial activity require increased supplies of sand and gravel. This means expanded surface mining and despoiled land near population centers. Highly competitive land use demands justify serious consideration of premining planning for multiple land use and reclamation concurrent with mining. 1-5 Formulating solutions to environmentally and economically sound uses requires a comprehensive approach based on properties of the natural resource base--geology, soils, and water. A study of sand and gravel mining within Pleistocene-Holocene fluvial deposits in Colorado County. Texas [(Fig. 1)] illustrates how physical limitations imposed by the resource base are determined.6,7 Data from drillers, logs of water wells, test boreholes, field observations, and laboratory analyses are used to evaluate these physical controls. Knowledge of the thickness and composition of overburden aids in developing optimum reclamation and revegetation plans. Most of the overburden in the study area [(Fig. 2, 3)] is a clayey mud with variable amounts of silt and fine sand. A comparative textural analysis of overburden and native soil is used to assess changes incurred by mining and for evaluating other physical characteristics, e.g., ability to support crops, permeability. and shrink-swell potential. Textures are correlated with soil types found in the area [(Table 1)] to get an approximation of probable surface properties expected from these mined materials. Results of textural analyses [(Table 2)] indicate that separating topsoils from overburden during mining is not necessary because the range of overburden textures is about that of native soils. However, more data is needed on nutrient deficiencies to evaluate fertilizer requirements for successful revegetation.*6

Jan 1, 1979

By I. N. Zavarine

THE observations presented in this paper were recorded during a study of the spheroidizing process. Spheroidization of cementite in steel is either brought about to develop a set of desirable mechanical properties or is an incidental result of mechanical and heat-treating manipulations. Physical properties of steel are materially influenced by the state of the cementite. Conversion of cementite from the lamellar to the spheroidal state is usually accom-panied by a decrease of hardness and of strength and by an increase in ductility. The spheroidized structure is usually considered as an ultimate step in the process of the softening of steel. The unorthodox hardening of a 3.5 per cent Ni steel (SAE No. 2330) after a heat-treatment that previously proved entirely suitable for a complete spheroidization of cementite in carbon steels led to the observa-tions that constitute the subject of the present paper.

Jan 1, 1939

By Nicholas T. Camicia

Coal is one of our oldest known commodities. Historic evidence indicates that this fossil-formed fuel was used in China and in Wales some 3000 to 4000 pears ago. Coal was discovered in North America in 1679 by French explorers in northern Illinois, and in 1700 a colony of Huguenots came across bituminous coal in Virginia. One might think by this long history of a single commodity that the string was about played out. Quite the contrary, coal is in greater demand than ever before and coal mining today is a modern industry. It is in an unprecedented growth period as the nation-and the world-demands more and more energy coincident with dwindling reserves of other fossil fuels. By the year 2000 the demand for coal is expected to at least double the current level of some 600 million tons annually despite the advent of nuclear power. To meet this challenge, the coal industry is vitally in need of an increasing supply of technically trained and progressive manpower. And, coupled with a serious shortage of engineers and technicians, it represents a rich vein of occupation opportunities-all the way up to top career levels. Today, coal mining is a complex, highly specialized industry concerned with more than just getting coal from the earth and putting it into the furnaces of the consumer. The industry is concerned with the environment, with maintaining a viable ecology. Recognizing the ramifications of global economics, the industry is very much aware of its important position in contributing to a constantly rising standard of living throughout the world. The key to rewarding employment in the coal industry is skill-skill that has been developed by education, training, and experience. None of these alone is enough; all three are necessary today to produce the skill needed to meet the employment requirements of the coal industry. Routine manual labor will no longer do the job in coal mining. In the United States coal mining has been mechanized to a degree unsurpassed anywhere else in the world, and the coal worker must be thoroughly

Jan 1, 1973

By David J. Mack

A SURVEY and critical appraisal of published information about Young's modulus was originally made by the writer because of a complete lack of information about this very important quantity in works on mechanics, physical metallurgy, physics, and other sciences. It was felt that a comprehensive summary of such information about Young's modulus might be of general interest and may suggest new problems or lines of attack on other problems that involve E. Hence this paper has been prepared even though it is only a review, with no new ideas or experimental data. The references are only those used in assembling the paper. No attempt was made to compile a complete bibliography on the subject of Young's modulus. CALCULATION OF YOUNG'S MODULUS FROM THEORETICAL OR EMPIRICAL CONSIDERATIONS Many attempts have been made to compute E from theoretical considerations. The earliest calculations were probably those of Tomlenson (1883) and Southerland (1891), but Fessenden 41,42 made extensive calculations a few years later and arrived at the relationship: [2E = 78. 101 (_L V] where V is the atomic volume. In 1923, Peczalski,43 working from the same stand-point but with more information available on atomic structure, arrived at an identical relationship, which he expressed as: [E=B(m) 2] where B is a constant of value about 8 • 10 7, p is density and m is atomic weight; the atomic volume, of course, being m/p. Portevin44 immediately pointed out that while the equations of Fessenden and Peczalski were true of the common metals, they gave low values for the refractory metals with high moduli (Fig. I). He showed (Fig. 2) that much better concordance was obtained by means of an empirical equation of the form: [E _ KT'Vb] where K is a constant; T the absolute melting point; V, atomic volume, and a and b constants of value approximately I and 2 respectively. This constant K in the Portevin equation is not necessarily the same for all elements, as shown by Thompson.45 Other equations for E based upon theoretical considerations have been derived by Honda and Yamada49 and Lasareff. 50 The most recent calculations of elastic moduli based upon quantum mechanics are probably those of Fuchs.46-48 He extended the method of Wigner and Seitz for calculating the lattice energy and compressibility of monovalent metals and computed the elastic constants of lithium,

Jan 1, 1945

By John T. Galey

In southwestern Pennsylvania 151 wells1 were completed during 1938, a total of 61 less than the preceding year. Of this number 81 were gas wells and 28 oil wells, which shows a considerable decline from 1937, when 108 gas wells and 64 oil wells were completed. However, 42 dry holes were drilled during 1938, which is two more than the previous year. Shallow Development—Gas No new extensions to old pools, or new wells that would indicate any substantial reserves, mere found during the year. However, a number of commercial wells and many dry holes were drilled to the Big Injun sand in Menallen township, Fayette County. One well had an initial open flow of 6 million cu. ft. In Rich Hill township, Greene County, one well producing, from the Big Injun sand, 2 million cu. ft. was brought in. Several other gas wells were completed in Shaler township, Alleghany County and Center township, Greene County, both of which had initial open flows of 1 million cu. ft. from the 30-ft. sand. Another well, in Aleppo township, Greene County, had an equal volume from the Gordon Stray sand. Oil Development has proceeded at a retarded rate because of the low price of Pennsylvania-grade crude. A total initial of only 205 bbl., an average of 7.3 bbl. per well, was developed. This is 1785 bbl. less than during 1937 and no new repressuring operations have been contemplated to prevent the declining production. The average price received for oil was $1.56 per barrel, with a high of $1.88 and a low of $1.34. This oil costs $1.94 per barrel2 to produce. The average price paid for Bradford

Jan 1, 1939

By John T. Galey

In southwestern Pennsylvania 151 wells1 were completed during 1938, a total of 61 less than the preceding year. Of this number 81 were gas wells and 28 oil wells, which shows a considerable decline from 1937, when 108 gas wells and 64 oil wells were completed. However, 42 dry holes were drilled during 1938, which is two more than the previous year. Shallow Development—Gas No new extensions to old pools, or new wells that would indicate any substantial reserves, mere found during the year. However, a number of commercial wells and many dry holes were drilled to the Big Injun sand in Menallen township, Fayette County. One well had an initial open flow of 6 million cu. ft. In Rich Hill township, Greene County, one well producing, from the Big Injun sand, 2 million cu. ft. was brought in. Several other gas wells were completed in Shaler township, Alleghany County and Center township, Greene County, both of which had initial open flows of 1 million cu. ft. from the 30-ft. sand. Another well, in Aleppo township, Greene County, had an equal volume from the Gordon Stray sand. Oil Development has proceeded at a retarded rate because of the low price of Pennsylvania-grade crude. A total initial of only 205 bbl., an average of 7.3 bbl. per well, was developed. This is 1785 bbl. less than during 1937 and no new repressuring operations have been contemplated to prevent the declining production. The average price received for oil was $1.56 per barrel, with a high of $1.88 and a low of $1.34. This oil costs $1.94 per barrel2 to produce. The average price paid for Bradford

Jan 1, 1939

By John T. Galey

In all, 210 wellst were completed in southwestern Pennsylvania during 1939, which is 59 more than were drilled during the preceding year. Of this number, 137 were gas wells, which is a considerable increase from the 81 completed during 1938. Only 25 oil wells were completed, as against 28 in the previous year, and 28 dry holes, 6 more than last year. Shallow Development—Gas The increase in the number of gas wells is largely the result of a search for additional gas in Armstrong and Indiana Counties. Although a considerable number of wells were drilled in the latter county, the majority of them produced less than 100 M cu. ft. initial open flow. In Armstrong County, a new pool was opened in Cowanshannock township, producing from the third Bradford sand. Several large wells were obtained there, one of which produced an initial of nearly 12 million cu. ft., with a reservoir pressure of 1100 Ib. However, the productive area has been fairly well outlined by further drilling and shows that the pool covers only about 800 acres. The sand is 20 to 30 ft. thick, and probably has 5 to 6 ft. of pay. Thus this reserve is not an important one. Several wells were found in Menallen township, Fayette County, where the Big Injun sand has been having a play for the past three years, but the activity there is much less than a year ago. Oil On the west side of the Bradford sand gas pool, Cowanshannock township, Armstrong County, a well was drilled which flowed 100 bbl. the first day from the Tiona sand. The probability is that this well is a freak, as the Tiona has been drilled within a fairly close distance on every

Jan 1, 1940