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By Frederick Prime

The first catalogue of Geological Reports of the United States was prepared by Prof. 0. C. Marsh, and published in the American Journal of Science and Ark for 1567, vol. xliii, second series. Since then the list has more than doubled, and it was thought that the publication of a new catalogue, brought clown to date, would be useful to many of the members of the Institute of Mining Engineers. The compiler will be most thankful to have any omissions or inaccuracies in the list sent to him, to be published as a supplement in the next volume of the Transactions. Especially to have the correct title, number of pages, plates, and maps of any volume on the list to which an * is prefixed, as he has been unable to personally consult such works. A preliminary list was issued last February, which has been almost doubled by the kindness of many friends. The writer desires more especially to express the obligations he is under to the following gentlemen : The Chief of Engineers, U. S. A.; Principal Dawson, Mr. G. M. Dawson, Drs. R. J. Harrington and T. Sterry Hunt, of Montreal; Mr. H. Engelmann, of La Salle, Ill.; Dr. F. V. Hayden and Prof. J. W. Powell, U. S. Department of the Interior; Prof. E. W. Hilgard, University of California; Prof. Henry Y. Hind, Windsor, N. S.; Prof. C. H. Hitchcock, of Dartmouth College; Mr. Henry A. Holmes, State Librarian, Albany; Maj. Jed. Hotchkiss, Staunton, Va.; Prof. W. C. Kerr, Raleigh, N. C.; Dr. J. S. Newberry, of Columbia College ; Prof. W. H. Pettee, of the University of Michigan ; Dr. Samuel H. Scudder, Prof. N. S. Shaler, and Prof. J. D. Whitney, of Harvard College; Mr. Sanderson Smith and Prof'. J. J. Stevenson, of New York; Mr. Addison Van Name, of Yale College, and Lieut. Geo. M. Wheeler, U. S. Engineers.

Jan 1, 1879

By R. F. Mehl, C. E. Birchenall

SINCE Maxwell1 first considered the self-diffusion process in 1872 its importance in the kinetic theory of matter has been recognized. Until the discovery of isotopes in 1913, a direct measurement of this quantity seemed impossible. The only information that could be gathered indirectly was for gaseous systems for which the kinetic theory was well developed. When methods of direct observation be-came available, investigations on self-diffusion were carried out in condensed phases. In metals these data are presumably of potential importance in the study of recovery, recrystallization, creep, sintering, and related phenomena. Following the pioneer work of Von Hevesy2 and his collaborators, who determined the rate of self-diffusion in lead with the naturally occurring thorium B isotope, several metals have been investigated. Pb, Ag³, Au.6,5, and Cu6,7,8,9 are examples of isotropic crystals existing in only one phase modification. Anisotropy of diffusion has been demonstrated in Bil6 and Znll. This paper is a study of a single metal in two allotropic forms and also of self-diffusion in a body-centered cubic lattice. Despite the fact that the measurements in each of the papers cited on self-diffusion in copper seem to be internally consistent to about 10 to 15 pet, the curves reported by different authors differ by factors of 2 to 4 at the same temperatures. This uncertainty may account, in part, for the failure to establish a successful correlation between the self-diffusion rates and other physical characteristics of the metals. No satisfactory theory of metallic self- diffusion has as yet been proposed to account for all the existing data and to permit estimation in other metals. Experimental Part: Two units of radioactive iron were used in these experiments, each a mixture of Fe53 and Fe59 (12). Fe53 decays by K electron capture and the emission of an X ray with a half life of about 4 years. Fe59 emits two beta spectra, one with a maximum energy of 0.26 Mev, the other 0.46 Mev, and gamma rays of 1.1 and 1.3 Mev, with a half life of about 44 days. They were present in nearly equal concentration initially. The composite half life started at about 50 days and increased as the Fe59 decayed, leaving Fe55 relatively more abundant. After aging a year, the half life was too long to measure significant decay in a month. The absorption properties also changed with time. Because of the importance of the absorption coefficient in the diffusion calculations, it was necessary to determine this quantity frequently over the period during which these experiments were carried out. This correction was unsuspected at the time of publication of notesl3 on this work and accounts for the discrepancy in alpha iron and for part of the discrepancy in gamma iron.* * The data in the present paper supersede those given in the notes entirely. In one note the scale of log D was inadvertently reversed. In addition to the correction for the drift in absorption coefficient, the D values for gamma iron at low temperatures were high owing to insuficient correction for diffusion occurring during heating and cooling through the high temperature part of the alpha range at a rate much slower than that employed in the runs reported here. The high temperature alpha rates are much higher than the low temperature gamma rates and correspond to large equivalent times at these temperatures. These experiments were discarded and new measurements taken. Independent experiments with the same activity units indicated a radioactive contaminant in the iron, but exhaustive attempts to isolate and identify it chemically failed. These experiments? indicate † These experiments will be discussed in a later publication from this laboratory. that the contaminant represented only a trace of little importance in the diffusion results. The active iron was plated from an iron chloride solution. Enough of the solution was dropped on a 1% in. square of filter paper to wet it thoroughly.

Jan 1, 1951

OFFICIAL INSTITUTE REPORTS FOR THE YEAR 1924 Report of the Secretary TO THE BOARD OF DIRECTORS OF THE AMERICAN INSTITUTE OF MINING AND METALLURGICAL ENGINEERS Gentlemen -To a Board of Directors keeping in as close touch with all of the affairs under their care as do the Directors of the A -I M. E, through their monthly meetings, a report of the year's progress is almost superfluous To the members who read the monthly reports of the Board Meetings and of the various activities of the Institute as published each month, a yearly report cannot carry much fresh infor¬mation, yet for both it may be well, as is the custom, to glance over the field of our activities during the past year, and to make an estimate for the year to come The beginning of 1924 was not propitious for the members of the mining profession, though tonnage, production for 1923 had been high and the gross value higher than for several years The margin of profit had been narrow, prospecting and development were limited, and many of our members were unemployed or were working in other industries Toward the end of the year, higher metal prices were in sight Old-time optimism began to grow, and it now brightens the outlook for 1925 An excellent barometer of the prosperity of the industry, and that of the Institute, for they go hand in hand, is the work of our Employment Bureau During the past few months, the percentage of our members for whom openings have been found has been increasing to a marked extent, and many members who had fallen in arrears are placing themselves in good standing The number of new members joining has remained about as it was in 1922 and 1923 The Directors have reason to congratulate themselves on the interest maintained during a dull period, for it is not humanly possible to take a keen interest in the technology of an industry when our hands and minds are not actively engaged in it Now, with a much brighter outlook, we can look forward to a year of increasing prosperity for the industry and for the Institute

Jan 1, 1923

By R. V. Norris

1. INTRODUCTION. THE anthracite coal trade, with a shipment averaging about 70,000,000 tons per year, differs essentially from other coal business, in the fact that the larger sizes, comprising about 65 per cent. of the total, are used almost exclusively for domestic purposes, principally during the winter months; and that for proper combustion close-sizing is imperative, so that eight sizes are made; broken, egg, stove, and nut, known as prepared sizes, and pea, buckwheat, rice, and barley, known as steam sizes. These sizes are made in the regular course of preparation, and but little variation in the natural percentage of each is practicable. Thus it is necessary either to work the collieries intermittently, or to dispose of all the varying sizes in their fixed proportions. Unfortunately, the market does not at all times absorb the coal in proper proportions, and rather than interfere with the regular operation of the mines it has been found economical to provide storage for the excess. While the cellars of the consumers are the great storage-plants of the country, this capacity is not under the control of the trade, except so far as reduced prices during the spring and summer months may tempt the use of this reserve. The same remark applies but with less force to the retail yards, which,, though usually small, store in the aggregate a large amount of anthracite. While every effort is made to utilize to the utmost the individual storage-capacity of the country, there still remains the necessity for taking care of the irregularities of the market by the construction of storage-plants under the direct control of the producers. Such plants are usually the property of the railroads, and are situated at points most convenient from a traffic stand-point.

Jun 1, 1911

By Jan Visman, S. J. Aresco

INTRODUCTION The accurate sampling of coal, as with most minerals, is a difficult task. Coal is a heterogeneous material made up of different types of coal and varying amounts of mineral matter. The product as mined may contain all the layers of coal and impurities found in the seam as well as portions of the stratas above and below the coal seam. The preparation plant is the device to size, crush, and/or remove impurities so the coal may be shipped as a salable product. Sampling may be needed at many stages in the preparation process. Although this chapter is primarily concerned with sampling in connection with preparation processes, the principles apply to all coal sampling. The main reasons for sampling in connection with coal preparation are: 1) To determine the washability characteristics of the raw coal by means of float and sink tests. These may be used for the design of a preparation plant, prediction of results to be obtained, or monitoring raw coal delivered to the plant. 2) To check the performance of various operating units in the plant, either by float. and sink tests or chemical analyses. 3) To determine the analytical characteristics of the products produced, such as moisture, ash, Btu, sulfur, etc. HISTORY The earliest accepted methods of sampling coal in the United States were given in US Bureau of Mines (USBM) publications by J. A. Holmes,l G. S. Pope,2 and A. C. Fieldner.3 The American Society for Testing and Materials (ASTM) more or less adopted the methods proposed by USBM in their Standard D-21-1916 and it remained a standard for many years. Briefly, this standard called for a 500 lb (227 kg) sample for coals less than 94 in. (19 mm) in size and a 1000 lb (454 kg) sample for all coals over 94 in. (19 mm) in size. No mention was made of increments, but there was an instruction that the sample should spread over the coal

Jan 1, 1979

By AIME AIME

In the present number of Mining and Metallurgy, issued on the fiftieth anniversary of the founding of the Institute, it appears appropriate to chronicle a few of the interesting incidents respecting its early life. We are fortunate in being able to cull the following notes from unpublished manuscripts of Doctor Raymond and Doctor Drinker, than whom no other members could have written with greater exactness and fidelity. THE seventh decade of the 19th century may be said to have marked an. era in the history of the world. Industrially and .commercially it was marked by the wide application and utilization of discoveries already made, which came to their full effect at this period in steamships, railways, telegraph and cable lines; the standardization of parts in machines, from watches to locomotives; the use of 'dynamite, antiseptic surgery, the open-hearth steel process, the compressed-air rock-drill, the electric generator, and the Gatling gun. Through the opening of the Suez canal in 1870 the maritime trade of the world was revolutionized, sailing vessels were supplanted by steamers, while ocean cables and ocean "tramps" brought about far more rapid movement of commerce than had before been experienced. Politically, this period was marked by the sudden birth of the German empire and the beginning of that intensive internal development of the national resources of that empire in preparation for colonial extension and war, the amazing result of which has been made evident by the recent world conflict. In the United States, the significance of this decade was peculiarly important. The re-admission to the union of Virginia, Mississippi, Texas and Georgia in

Jan 1, 1921

By Andrew Fletcher

AS good health is the most important asset in life, the development of healthful conditions should be the one common meeting ground of agreement between management and labor. Health should not be a subject to be pulled apart, shoved around, or bargained about. Differences of opinion may exist in the procedure and techniques employed in approaching the goal of maintaining the health of workmen, and in the method of increasing the ultimate profit of the employer by improved working and living conditions. Such matters are doubtless appropriate subjects for discussions between the interested parties, but techniques are only tools. If an employer fails to remedy a hazard or a menace which contributes to poor working condlions, this constitutes a legitimate grievance. It should not be necessary, however, nor is it desirable that fundamentals of health maintenance become matters of collective bargaining, any more than should the principles of management and engineering. I have been especially concerned during the last few months with the propaganda in collective bargaining negotiations throughout the country for including in union contracts a given number of days of sick leave with pay. We all

Jan 1, 1946

By H. 0. HOFMAN AND W. MOSTOWITSCH

I. INTRODUCTION. THE mineral gypsum, CaSO, + 2 H2O, has been used for many years as a sulphurizing and basic flux in several smelting¬operations. Thus, in smelting oxide nickel-ore in the blast furnace, it is commonly added to the charge to furnish the sulphur necessary for collecting the metal in a matte, and a base for slagging the siliceous gangue. In the concentration of lead-copper matte in the reverberatory furnace it has been used for years at Freiberg, Saxony1 for a similar purpose, and for producing at the same time a copper-matte with less than 0.15 per cent. Fe. The latest use gypsum has been put to is in the blast-roasting process of Carmichael-Bradford.2 The term "blast-roasting," given by A. S. Dwight3 to the Dwight-Lloyd method of roasting and agglomerating ,I is a happy generic term which covers the ground better than the " lime-roasting" of Ingalls' or the " pot-roasting " of Austin,6 in that it leaves the operation independent of the character of the flux and the form of apparatus, and retains the characteristic feature of this class of processes-namely, that of using forced draft. In the Carmichael-Bradford process the dehydrated material, mixed with galena-concentrate, acts as a diluent and a flux. The process differs in this from the Huntington-Heberlein7 and the Savelsberg8 processes, in both of which limestone is used.

Jan 1, 1909

By Louis D. Huntoon

SHORTLY after publication of the article in the July, 1924, issue Of MINING AND METALLURGY, entitled "Canada as a Gold Producer," requests were received to determine the ownership of production. Advices have also been received that considerable discussion has taken place on the same questions both in Canada and Great Britain. The author is indebted to R. H. Coates, Dominion Statistician, and George C. Bateman, Secretary, Ontario Mining Association, for the following figures and takes this opportunity of expressing his appreciation. There have been no statistics compiled as to ownership of production. Statistics were compiled as of Dec. 31, 1921 relative to the distribution of stocks, bonds and "other securi¬ties" in industrials, agriculture excepted, throughout the Dominion, and "distribution of ownership of securities issued by mining companies incorporated and operating in Ontario" for the same year. Stock registration does not necessarily represent actual ownership' as large blocks may be endorsed and not transferred; neither does registration actually represent production. When the charts are studied individually and collectively one cannot help but be impressed with the fact .that in the mineral industry of Ontario and the Dominion at large, Canadian registration predominates, the United States registration is about half that of Canada, and Great Britain is about half that of the United States. When the nickel-copper industry is excepted the British registration falls to a very low percentage. Since Dec. 31, 1921, British capital has commenced to flow into mining enterprises in Ontario and it has been already rewarded by the discovery of valuable ore deposits.

Jan 1, 1925

By AIME

SUPPLEMENTING surveys of the engineering profession regarding salaries and advancement, based upon data from individual engineers, a survey through a questionnaire to employers of engineers has recently been made by a subcommittee of the Engineers Joint Council's Committee on the Economic Status of the Engineer. Its object was to learn directly from employers their attitudes and policies pertaining to the selection, training, placement, advancement, guidance, and professional activities of engineering graduate employes. The questionnaire was sent in May 1946 to 174 employers of engineers, including colleges. Replies were received from 104 employers in nineteen fields of industry, who employ about 2,000,000 persons, about 40,000 of whom are engineers. The following general observations are based on the questionnaires returned. Who Are Hired? Of the co-operators 96 per cent employ cadet engineers directly upon graduation from engineering schools, but only 4 per cent recruit their engineering staffs exclusively from the new graduates. About 43 per cent hire more than half of their new engineer employes after one or more years' experience with other employers. This is evidently a matter of necessity or expediency rather than preference, because more than sixty per cent of those reporting indicate that they prefer to hire the new graduate.

Jan 1, 1947

By Eugene McAuliffe

THE heavy shrinkage in the production of bituminous coal has reflected adversely in the matter of tonnage produced by stripping arid mechanical loading machinery. The purchase of stripping and underground loading equipment has likewise been circumscribed. How- .ever a growing percentage of bituminous coal is being loaded by stripping and mechanical loading machinery. This situation is due to the fact that numerous strip pits were able to operate in Illinois and Indiana when under- cover mines were subjected to labor interference, a further advantage gained by their ability to produce and market coal at a price below that of the undercover mines. The mines equipped with mechanical loading. apparatus have enjoyed more continued operation for the double reason that the companies using coal-loading machinery are, generally speaking, more substantial and in better financial condition than many of the smaller properties who maintain hand-loading methods, and the market advantage due to lower production costs also reflects to the advantage of the undercover mines using mechanical loading equipment. Where a number of mines are con- trolled by one company, those not equipped with loading machinery and suffering from higher producing costs have often been closed, with the available tonnage concentrated in the more modernly equipped mines.

Jan 1, 1933

By L. Weaver

THE Tennessee Copper Co.'s mines are in the southeast corner of the state of Tennessee. Polk Co., in the well-known Ducktown copper basin. Their new circular production shaft will eventually be the only ore hoisting shaft, and is located for handling ore from Boyd, Calloway, Mary, and Cherokee mines. A circular, rather than a rectangular, shaft was decided upon because: 1-The circular shaft section is stronger when lined with concrete. Reinforcing steel was not required, thus reducing lining cost by one- quarter. 2-Water sealing was desired; it was thought it could best be done with a concrete lining followed by pressure grouting to eliminate water seeps. 3-The shaft labor saving equipment could best be used in a large opening, so the round section was made for economy, sinking, mucking, concreting and water sealing. Less shaft steel is used than could have been possible with steel sets. There are no posts required; center beams and Tee plate assembly placed at 10 ft hold the 100 lb steel guide rails. The shaft is 12 ft 7 1/2 in. ID of the concrete walls. This is large enough for two 10-ton hoisting skips and a ladder compartment. One of the skip compartments is for hauling equipment. The grouting equipment was a 2%xlO-in. Gardner-Denver grout pump, air powered and developing 1000 lb pressure. A grout mixer, also air driven, fed the mixed solution into a tank coupled to the pump suction. Grout materials used were mostly water and Portland cement. Some Bentonite was used to seal porous ground near the surface.

Jan 11, 1950

By I. Cadoff, J. P. Nielsen

The Ti-C phase diagram exhibits a peritectic point at 1750°C and 0.8 pct C, and a peritectoid point at 920°C and 0.48 pct C. The maximum solubility of carbon in a titanium is 0.48 pct. The 6 region containing the Tic compound (20 pct C) extends to 11 pct C at the peritectic temperature. THE interest in the Ti-C alloy system stems from the fact that carbon occurs as an impurity in titanium alloys when graphite electrodes or graphite crucibles are used in their melting. Since titanium-base alloys are still in the development stage, some virtue may be found in carbon addition to titanium. The Tic compound is currently emerging as an important powder metallurgy base constituent similar to the WC compound. Ehrlich' identified the phases and structures present in the Ti-C system. The peritectoid region of the phase diagram was investigated by Jaffee et al." A preliminary diagram based on theoretical considerations was proposed at the outset of this research." The Tic compound has been investigated extensively and has been reported on in a large number of papers. Experimental Procedure Arc-melted alloys of 24 compositions in the range 0 to 20 wt pct C were investigated using metallography, X-ray diffraction, and, for the liquidus and solidus regions, incipient and complete melting. All alloys were prepared from iodide titanium (New Jersey Zinc Co., 99.95 pct Ti minimum) and spectroscopic grade carbon (National Carbon Co.). To prevent carbon spattering during arc melting the carbon was encapsulated in titanium. For alloys containing less than 1 pct C the powder was inserted into a capsule formed by drilling a hole in the as-received rod. For higher compositions, capsules were formed from titanium sheet. Arc Melting: The charges were melted in the copper-hearth cold electrode furnace shown in Fig. 1. This furnace is similar in principle to the all-metal unit adapted for titanium melting at Battelle Memorial Institute.' The transparent pyrex walls giving unlimited visibility during operation and the multiple-

Jan 1, 1954

By R. G. Hudson, H. W. Paxton

The activities of iron and chromium in their binary system have been measured by the Knudsen orifice technique. The system is close to ideal at 1200- 1250 C with slight positive deviations. The effect of this on the liquidus and solidus is discussed and these are calculated for two limiting assumptions. The vapor pressure of pure iron, pure chromium, and one alloy is compared with that obtained by the Langmuir free-evaporation technique. The results agree, indicating a vaporization coefficient close to 1. HERE are no reported data on the thermody-A namic activity of iron and chromium in the solid portions of the phase diagram. It is generally assumed'.' that the liquid solutions of iron and chromium obey Raoult's law. Chen and Chipman" have inferred that the liquid solution obeys Raoult's law. The minimum' in the solidus-liquidus curves for the iron-chromium system shows that there are deviations from ideality in either the solid or liquid or both. Because of the importance of developing reliable techniques for obtaining activity data in alloy systems at high temperatures and of the data so obtained, an investigation of the activity of iron and chromium in the binary at 1200-1250 C was undertaken using the Knudsen cell. Experimental The apparatus and experimental procedures used in this investigation were described in a previous paper." The various materials used for the construction of the Knudsen cell are listed in Table I. The metal used for the determination of the vapor pressure of chromium was 99.9 pet pure, obtained from A. D. Mackay, Inc. The iron was obtained as electrolytic grade from Fisher Scientific Company. The Fe-Cr alloys used are shown in Table 11. The largest error and controlling factor in the accuracy in the experiments reported here are introduced because of temperature uncertainty, which is estimated to be ±3 deg C. This introduces an uncertainty of 26 pet in the measured pressure. Experimental Results and Calculations The vapor pressures of pure iron and pure chromium were calculated from the measurements by the Knudsen equation3 on the assumption that only Cr or Fe atoms were present in the gas phase. For metal vapors, at the high temperatures and low pressures involved in these measurements this should be a reasonable assumption. Whitman" corrections for the cells were made. The data and results of pressure calculations are presented in Table I, and are plotted in Fig. 1. In addition the heat of vaporization at the absolute zero, ?E°°, has been calculated for chromium. These calculations are summarized in Table 111. The data used in these calculations are as follows kelley13 (F° - E°°/T ) Speiser, et al H (F° - E°°/T ) 010 where F" — standard free energy at temperature T It was necessary to calculate the total pressure above the alloys from the total weight loss W of the cell during a run, because of the fact that all attempts to collect and analyze the chromium and iron vapor effusing from the cell in the apparatus available failed. The failure resulted from the re-

Jan 1, 1959

Aamot, Olav Crone, (M'29) Chem. Engr., Elektro¬kemisk, Raadhusgt, 23; Oslo, Norway. Abadilla. Quirico A., (M'33) Min. Engr., Dir., Bureau of Mines, Manila, P. I. Abbott, Agatin T., ( J'40) Asst. Geol., Trench Mine, Patagonia, Ariz. Abbott, Clarence E., (M'04) Civil Engr., V.P., Tennessee Coal Iron & R. R. Co.. 159'3 Brown Marx Bldg.. Birmingham, Ala. Abel, Raymond L., (M'28) Chem. Engr., Chief of Inspection Div., Pittsburgh Chem. Warfare Pro¬curement Dist., American Batik Bldg., Pitts¬burgh. Pa. Abel, Walter D., (M'32) Min. Engr.. Div. of Cor¬porations, State of Calif.. 403 California State Bldg., Los Angeles, Calif. Abele. Louis T., (M'31) 4800 Patterson Ave.. Richmond, Va. Abell, Leo M., (M'311 Research Met., Mount Mor¬gan Ltd., Mount Morgan, Queensland, Australia. Abenius, Hakan V., (M'37) c/o Falu Gruva, Falun, Sweden. Abernathy. G. E., (M '33S) Geol., Kansas State Geol. Survey. Pittsburg, Kan. Abernathy, Jack. H.. (M'40) Chief Engr., Sunray Oil Co.. Philtower B1dg., Tulsa. Okla. Ahorn, Robert H., (M'19) Asst. Met., Research Lab., U. S. Steel Corp., Lincoln Highway, Kearny, N. J. Abraham, A. W., (M'30) Petr. Engr., Richfield Oil Corp., 555 S. Flower St., Los Angeles. Calif. Abramowitz, William L., (J'40) Chem., National Oil Products Co., Harrison, N. J. Abrams, Charles Jackson, (M'36) Gen'l Supt., Climax Molybdenum Co.; Climax, Colo. Abstein, Henry T., (M'27) Yellow Pine, Idaho. Ackerman, D. E., (M'35) McKinsey & Co., 2 Wall St., New York, N. Y. Ackerman. E. Dumont, (A'3S) Petr. Geol.. Dist. Geol., Quiriquire' Dist., Standard Oil Co. of Venezuela, Caripito, Venezuela.

Jan 1, 1941

By W. P. Haynes

ESTIMATED United States crude-oil production during 1943 established a new annual peak of 1,500,000,000 barrels, a daily average of 4,118,000 barrels. This would be an increase of 315,000 barrels per day, or 8 per cent over 1942 and 7 per cent over 1941, the previous peak. During the first ten months of the year, production jumped from 3,782,000 barrels per day in January to 4,400,000 in October. Available data for the last two months of the year indicate a leveling off of this trend, with daily rates slightly above 4,400,000 barrels.

Jan 1, 1944

By S. J. Green, R. D. Perkins

Little data exists on the high strain rate behavior of geologic materials. Uniaxial stress tests by Kumar1 and by Serdengecti and Boozer2 present some results to strain rates in the range 10 to 103 per sec. The two references cited are the only ones the authors found for high strain rates. Techniques for experiments at high strain rates are not well developed and, in general, leave questions with respect to interpretation of data when the material behaves in a brittle manner. The most reliable data at very high strain rates (104 to 106 per sec) are found in some recent flat-plate work3-5 where experimenters have impacted one plate into another, thereby creating a uniaxial strain loading. The standard uniaxial stress-strain curves cannot be obtained directly from these tests; however, yield (or fracture) may be studied by measuring the "elastic" wave magnitude. These data then may be compared to uniaxial stress data by resorting to some preassumed yield/fracture criteria. Even with the most liberal interpretation of existing data, little can be said of the effects of high strain rate on stiffness, yield/fracture, and post-fracture behavior of geologic materials. It is the purpose of this work to begin to add to the understanding. The data presented here are intended to provide material information for use in calculating the response of geologic materials to high rate deformations. These data can be applied directly to determine parameters such as the elastic modulus and Poisson ratio as a function of stress. Furthermore, these data can be used to derive an understanding of yield/fracture and the effect of rate on the yield/fracture surface. The work presented is a first step, and is

Jan 1, 1972

By AIME AIME

THE following compilation of State bureaus and officials that deal with mineral resources is compiled in part from a new "Check List of State Agencies and Officials Concerned with the Management of Natural Re- sources," compiled for the National Resources Committee, Washington, D. C., by Clifford J. Hynning. Alabama-Geological Survey of Alabama, University. Walter B. Jones, State Geologist. Chief Mine Inspector: W. B. Hill- house, 614 Lincoln Life Bldg., Birmingham.

Jan 1, 1939

By J. E. Burke, C. W. Mason

In attempting to study precipitation from a tetragonal lattice, using solid solutione of bismuth in tin, it was found that although a Widmanstätten pattern is observed1,4 only a qualitative analysis of the orientation relationships is possible, because of the unusual structural changes that accompany the precipitation process. Microscopical Studies Alloys were made from Chempur tin (Standard samples 42b and 426, National Bureau of Standards), and bismuth (Kahl-baum C.P.) by melting weighed quantities together under palm oil, stirring well, and castilig in a heated graphite mold. The polishing and etching techniques employed largely govern the visibility of the structural changes. The preliminary surfacing operations were similar to those recommended by Villela and Bergekoff,5 through Behr-Manning 3/0 abrasive papers, lubricated by a solution of paraffin in kerosene. A rough metallographic polish was next given, using a thin cotton cloth charged with relevigated alumina (maximum particle size of about 4µ) and soap solution; repeated etching and polishing served to remove disturbed metal. For high-power examination better preparation was necessary. It was found that on such soft metals the threads of the fabric, rather than the abrasive, cause most of the scratching. Cotton outing flannel, which had been brushed so that the nap lay down, was fairly satisfactory, but a heavy grade of silk velvet (not the noncrushable kind) was found to be better, especially after some use. A better procedure was as follows: The metal lap was warmed slightly, and a 4-in. circle of woolen broadcloth was cemented to its center by a thin film of melted paraffin. The broadcloth was then moistened with water, and a 30 to 40 per cent solution of sodium hydroxide heated to about 50°C. was poured over it, allowed to stand for I to 2 min. and then washed off. It was neither necessary nor desirable to remove all the sodium hydroxide from the cloth, since its etching action aided in the removal of the flowed layer from the sample. The cloth was then charged with a paste of the relevigated alumina in water. Since this lap did not remove deep scratches, it was necessary previously to polish the specimen on some material such as the silk velvet. The sodium hydroxide softens and partly gelatinizes the woolen lap covering, permitting a scratch-free polish, but its action continues, and the cloth deterioratcs after about 24 hr. This is not serious, because a new lap can be prepared in about 5 min., and only small pieces of cloth are used. Etching with a strongly acid solution of ferric chloride was found satisfactory for removing the flowed layer. For the final etching, the most satisfactory reagent was that of Tafls,7 the formula for which is: FeC13.6H2O, 2 grams; HC1, 5 c.c.; H2O, 30 c.c.; C2H5OH (95 per cent), 60 C.C. This etchant reveals differences in com-

Jan 1, 1942

By J. E. Burke, C. W. Mason

In attempting to study precipitation from a tetragonal lattice, using solid solutione of bismuth in tin, it was found that although a Widmanstätten pattern is observed1,4 only a qualitative analysis of the orientation relationships is possible, because of the unusual structural changes that accompany the precipitation process. Microscopical Studies Alloys were made from Chempur tin (Standard samples 42b and 426, National Bureau of Standards), and bismuth (Kahl-baum C.P.) by melting weighed quantities together under palm oil, stirring well, and castilig in a heated graphite mold. The polishing and etching techniques employed largely govern the visibility of the structural changes. The preliminary surfacing operations were similar to those recommended by Villela and Bergekoff,5 through Behr-Manning 3/0 abrasive papers, lubricated by a solution of paraffin in kerosene. A rough metallographic polish was next given, using a thin cotton cloth charged with relevigated alumina (maximum particle size of about 4µ) and soap solution; repeated etching and polishing served to remove disturbed metal. For high-power examination better preparation was necessary. It was found that on such soft metals the threads of the fabric, rather than the abrasive, cause most of the scratching. Cotton outing flannel, which had been brushed so that the nap lay down, was fairly satisfactory, but a heavy grade of silk velvet (not the noncrushable kind) was found to be better, especially after some use. A better procedure was as follows: The metal lap was warmed slightly, and a 4-in. circle of woolen broadcloth was cemented to its center by a thin film of melted paraffin. The broadcloth was then moistened with water, and a 30 to 40 per cent solution of sodium hydroxide heated to about 50°C. was poured over it, allowed to stand for I to 2 min. and then washed off. It was neither necessary nor desirable to remove all the sodium hydroxide from the cloth, since its etching action aided in the removal of the flowed layer from the sample. The cloth was then charged with a paste of the relevigated alumina in water. Since this lap did not remove deep scratches, it was necessary previously to polish the specimen on some material such as the silk velvet. The sodium hydroxide softens and partly gelatinizes the woolen lap covering, permitting a scratch-free polish, but its action continues, and the cloth deterioratcs after about 24 hr. This is not serious, because a new lap can be prepared in about 5 min., and only small pieces of cloth are used. Etching with a strongly acid solution of ferric chloride was found satisfactory for removing the flowed layer. For the final etching, the most satisfactory reagent was that of Tafls,7 the formula for which is: FeC13.6H2O, 2 grams; HC1, 5 c.c.; H2O, 30 c.c.; C2H5OH (95 per cent), 60 C.C. This etchant reveals differences in com-

Jan 1, 1942