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By John V. Beall

Ten years ago, upon coming home to New York, we had money in the bank, a portfolio of stocks, a rent- controlled apartment overlooking the Hudson and we didn't own an automobile. This was bliss! The just reward of industry and careful management of the fruits of our labor in the mines overseas. Although we kept up a delaying action, the family was pushing hard for a house in the suburbs. We were able to find something wrong with every house that came up but, finally, in a weak moment made the unlikely compromise of putting ten dollars down on a piece of property in Westchester County.

Jan 1, 1971

(Members are urged to send in for this column any notes of interest concerning themselves or their fellow-members.) Members and guests who registered at Institute headquarters during the period Apr. 10 to May 10, 1915: William W. Elmer, Tuttletown, Cal. R. R. Freeman, Jr., Wollaston, Mass. Lawrence Addicks, Douglas, Ariz. Francis R. Pyne, Elizabeth, N. J. W. F. Durand, Stanford Univ., Cal. George B. Pickett, Ophir, Colo. S. P. Cooper, New York, N. Y. R. V. Norris has been elected President of the Columbia School of Mines Alumni Association. Robert C. Sticht has been elected President of the Australian Insti¬tute of Mining Engineers.

Jan 6, 1915

By Robert C. Munro, Kenneth M. Reim

NEW IDRIA INTRUSIVE For the most part this ultrabasic mass is a highly sheared serpentine, the exposed rock being made up of small serpentine chips and plates, the faces of which have been slickensided. Throughout this sheared material there are residual blocks of serpentine and highly to moderately serpentinized peridotite. The faces of these resistant blocks show rounding and slickensiding and their size varies from pebble size to diameters of over 5 ft. Certain areas have seemingly resisted the shearing stresses and remain as moderately fractured serpentine. Throughout the ultrabasic mass are bodies of silica-carbonate rock, silicified serpentine and minor concentrations of magnesite and chromite.

Jan 9, 1962

By Paul B. Barton

Unconventional mineral deposits are those that differ significantly from productive deposits in mineralogy, grade, or geologic setting. Thus, the initial representatives of each deposit type are, by definition, “unconventional” until they are exploited. The “unconventional” status changes to "conventional" because of economic shifts (e.g., bulk silver ores), because of technological innovations (e.g., froth flotation), or simply through the recognition of, and production from, novel mineral concentrations. Heretofore the discovery of new deposit types has been almost entirely accidental, but the long- established concept of the geochemical cycle provides a nearly untouched opportunity and challenge for the application of geochemistry in predicting novel, potentially economic, mineral concentrations.

Jan 1, 1983

By W. David Leyshon

This paper compares the general characteristics of Florida phosphate rock for the manufacture of fertilizers and phosphoric acid. The subjects covered are relative reactivity for superphosphate manufacture and various properties of the rock for use in phosphoric acid production, including gypsum filterability, sulfuric acid consumption, foaming, relative cor-rosiveness, chemical composition, and others. Comprison will include rocks of North Africa, the western U.S., and other locations. This paper reviews some of the important properties of phosphate rock, giving particular attention to a comparison of Florida phosphate with some of the major phosphates produced in the world. It also discusses some of the techniques available for evaluatine Phosphate. rock for phosphoric. acid and fertilizer use. The use of Florida rock outside the U.S. has been increasing steadily, evidence in itself of certain desirable properties of this rock. Table I is a list of the major producers and exporters of phosphate rock as of 1965. Florida, meaning in this case Central Florida, was the largest producer of phosphate rock and the largest exporter of rock. Of a total world production estimated at 60 million tons, about 50 million tons were produced during 1965 by the areas listed in Table I. One major producing area omitted from Table I and from subsequent evaluations in this paper comprises Nauru, Ocean, and Christmas Islands, whose output totaled about three million tons in 1965. This phosphate is marketed entirely by the British Phosphate Commissioners, primarily in Australia and New Zealand, and does not get into the world market elsewhere to a significant degree at the present time. South Africa, Egypt, Israel, and North Vietnam also produce lesser quantities of rock for the international market, and these materials are also excluded from this review. The phosphate industry is now seeing the introduction of several new areas that will be significant factors in the rock market in the future. The North Carolina and North Florida areas each have capacity at present or in the near future for producing about three million tons per year. The Djebel Onk mine in Algeria has a potential of about 800,000 tons per year. In addition, announcements have been made of significant development of deposits in Peru and in the Spanish Sahara, and sizable expansions are planned in several of the existing areas that are now of minor importance. Competition for the rock market appears to be increasing so that more attention will probably be paid to evaluating phosphates available from different areas. It is not possible here to go into all the properties of even a few of the materials listed in Table I. However, it is practical to discuss some comparative properties important for making phosphoric acid and fertilizers, and to touch on the techniques used for the evaluation of various phosphate rocks. Table II gives typical analyses of the major phosphate rocks available in the world as of 1965. There is, of course, an inherent danger in labeling any analysis as typical, but it appears that variations between two samples of rock within one given area are generally less than between two samples from different areas. The analyses listed were compiled from several years of data so they may not be representative of the present output of any particular area. The range of grades represented by these analyses goes from 66 BPL for Gafsa rock to 85 BPL for Kola

Jan 1, 1968

The sudden and untimely death of Dr. Charles R. Van Hise, late' president of the University of Wisconsin, was one of the greatest losses, not only to the educational world and science of geology, for which he was a great leader and pathfinder, but also to the world of mining and allied interests, for which he was an adviser and helper who blazed trails and pointed out paths of development, which the practical men of englneering and industry will follow long after his death. To the general public, Dr. Van Hise stood as a great educator who conceived and wrought out a new idea in the people's university .of .a commonwealth and as a great active mind that could not be held within the bounds of education and science but, by its own bigness and broadness, was forced into the contemplation of the larger affairs of the nation. To the engineering profession, dr. Van Hise will be remembered as a tireless worker who solved some of the most complex problems in geolpgy and the development of mineral resources and recorded these findings In a form that is of lasting value to those who follow him in similar labor. In this combination of thinker and worker, educator and economic student, scientist and practical engineer, lies Dr. Van Hise's contribution to his generation. As an educator, Dr. Van Hise attained perhaps his widest recognition, for in the University of which he was president he evolved and accomplished a new idea, which caused it to be called, in 1908, by President Eliot of Harvard, "the leading State University." At the time of his death, Nov. 19, 1918, he was just completing fourteen years as president and forty-three years as student and teacher in the University. His entire life of 61 years had been devoted to his State and its University. He was the first alumnus of the University and the first Wisconsin-born citizen to become its president—and he enjoyed the longest term as president of the institution. Since his graduation from its College of Engineering in 1879, he had been constantly a member of its faculty. As Chief Justice John B. Winslow, of the Wisconsin Supreme Court said at the time of President Van Hise's death, " Wisconsin has had many able sons, men who have served their Country and their State with ais-tinguished honor in various fields of effort, but among them all none, I believe, has rendered greater service in his time than President Van Hise. The University will be his true monument, for to him, more than to any one person, we owe the present commanding position of that, great Institution." What his "new ideal of a State University" was maybe best expressed in the words which he used to outline it in his inaugural address in 1904. "I shall never be content until the beneficent influence of the University of Wisconsin reaches every family of the State. This is my ideal of a State University. When the University of Wisconsin attains this ideal, it will be the first perfect State University.... The University of Wisconsin desires to prevent that greatest of all economic losses to the State, the loss of talent. To prevent this loss of talent, the University must not only provide for those who come to Madison for instruction, but must go out to the people of the State with the knowledge which they desire and need." Hence it was said early in his administration that "the boundaries of the State are the campus fence."

Jan 1, 1920

By D. Moskowitz

IN the course of a general investigation of boride systems, sponsored by the Office of Naval Research, various vanadium boride powders of relatively good purity were prepared which could be used for a determination of the phases present. The X-ray pattern of one of these lots showed, in addition to the known VB1 and VB22 phases, an additional phase, almost certainly of composition V3B4, isomorphous with Cr3B4, Cb3B4, Ta3B4, and Mn3B,. Its pattern fitted in well with the indices worked out by Kiessling for Mr3B4.3 The unit cell for this new compound is orthorhombic, with the dimensions a = 3.030A, b = 13.18A, c = 2.986A7 V=119.2A.' Table I lists the X-ray diffraction data for V.3,.

Jan 1, 1957

By T. A. Wright

THE SAMPLING of waste materials containing copper, lead and tin has taken on a new significance within recent years, and is of increasing importance, on account of the entry of some of the copper refineries into this field and the tendency towards consolidations among the smelters. In the past, such material was sold on the basis either of a rough or grab sample or of casual inspection of the lot. The two principal sources of this waste are the processes of fabrication and the scrapping of automobile, electrical, plumbing, railroad and other equipment. In both cases much material can be sorted, salvaged and sold by classification and grade to be melted "as is" or with the addition of new or virgin metal. The increasing care in classifying exercised in the large manufacturing plants tends to increase the proportion of this usable scrap; on the contrary, the increasing use of more complex and special non-ferrous alloys tends to make sorting and grading more difficult in turnings, borings, clippings, etc., and consequently is making sampling of more moment. In tin, lead, aluminum, and zinc furnace by-products such as ashes, drosses, skimmings, etc., the trade practice of evaluation has not varied much. For instance, tin drosses, battery lead, and aluminum skimmings are ordinarily sold on what is called "metallic button" or "metallic recovery" or "metallic yield." Copper and lead waste, however, is being sold more and more on actual copper and lead contents based on sample and chemical analyses. This paper will be devoted chiefly to the sampling of materials suitable only for refining and recovery of one or more of the metals present. The methods described are often based on the fact that but one metal, such as copper, is to be paid for. The loss of volatile constituents in melting does not appreciably affect the final copper result, as the "after-melting" assay can be readily calculated to the "before-melting" basis, but if smelter efficiency continues to increase, so that in time zinc, for instance, may be recovered on a paying basis, the method of sampling dirty brass, for example, will have to be changed also.

Jan 1, 1928

By George S. Lockwood

Plans are moving ahead toward the July 1965 start-up date for Kaiser Steel Corp.’s new pelletizing plant at its Eagle Mountain, Calif., iron mine. Capacity will be 2 million long tons of pellets containing 65% Fe. A major portion of the output is scheduled for charging into Japanese blast furnaces as the result of a contract to supply Mitsubishi interests with 10.8 million tons of pellets over a six-year period. Kaiser's concentrating plant at Eagle Mountain plus sintering facilities at Fontana are adequate to meet the requirements of its blast furnaces, which, as a consequence, are not expected to take any substantial quantity of pellets during this period. However, some 200,000 tons of pellets per year is scheduled to be used for the production of special steels and in the open hearths as a substitute for the high-cost ores now being used.

Jan 8, 1964

By T. A. Wright

THE SAMPLING of waste materials containing copper, lead and tin has taken on a new significance within recent years, and is of increasing importance, on account of the entry of some of the copper refineries into this field and the tendency towards consolidations among the smelters. In the past, such material was sold on the basis either of a rough or grab sample or of casual inspection of the lot. The two principal sources of this waste are the processes of fabrication and the scrapping of automobile, electrical, plumbing, railroad and other equipment. In both cases much material can be sorted, salvaged and sold by classification and grade to be melted "as is" or with the addition of new or virgin metal. The increasing care in classifying exercised in the large manufacturing plants tends to increase the proportion of this usable scrap; on the contrary, the increasing use of more complex and special non-ferrous alloys tends to make sorting and grading more difficult in turnings, borings, clippings, etc., and consequently is making sampling of more moment. In tin, lead, aluminum, and zinc furnace by-products such as ashes, drosses, skimmings, etc., the trade practice of evaluation has not varied much. For instance, tin drosses, battery lead, and aluminum skimmings are ordinarily sold on what is called' "metallic button" or "metallic recovery" or "metallic yield." Copper and lead waste, however, is being sold more and more on actual copper and lead contents based on sample and chemical analyses. This paper will be devoted chiefly to the sampling of materials suitable only for refining and recovery of one or more of the metals present. The methods described are often based on the fact that but one metal, such as copper, is to be paid for. The loss of volatile constituents in melting does not appreciably affect the final copper result, as the "after-melting" assay can be readily calculated to the "before-melting" basis, but if smelter efficiency continues to increase, so that in time zinc, for instance, may be recovered on a paying basis, the method of sampling dirty brass, for example, will have to be changed also.

Jan 1, 1928

By W. P. Blake

Wm. P. Blake, New Haven, Conn. (Communication to the Secretary, June, 1889): It is gratifying to find that Prof. Carpenter in his paper sustains the accuracy of my original determination of

Jan 1, 1889

By J. P. Lesley

The old do not love to see the young pass away from the light of the sun before them. Fathers would fain keep their sons by their side to the. end of life ; but the old Greeks, who loved the old gods, were wont to moderate their grief with the sweet superstition that only those whom their gods especially loved died early. The Christian church found consolation in that superstition applied in a new form to its new sorrows, and paid its most enthusiastic devotion to the memories of its young and beautiful martyrs. The natural science of our century is robbing us fast of this and all other superstitions, sweet as well as bitter, and leaving us for consolation to the teaching—colder, yet kinder—of personal fortitude and that optimism Which intelligently translates the Cosmos of Humboldt back into its old name of the Harmonia of Pythagoras. The Homeric Kataclothes, the three fates, are dead and gone for us, with that old world which comprehended none of the laws of cause and effect, and sorrowed for those who were cut off from the land of the living without hope of more than a shadowy existence beyond the river of death. All the more the ancients cherished the memory of their dead and lavished their choicest art upon their monuments. We moderns have lost the monumental arts, but we better keep the monuments which our dead leave behind them. No one of us who has done good work can fail to be remembered; and in an Institute like this, which keeps the press at work, an immortality in the memory of men is more possible, more certain, for every one of its members than the greatest heroes of antiquity could anticipate for themselves. In old apocalyptic times the works of men followed them through death to the throne of God to be their advocates in judgment, but in these modern times our works remain this side the grave, to follow the name of the departed one as it takes its course along the history of his peculiar art or science advancing slowly to perfection. We write the epitaph, not upon the mouldering stone of a tomb, but on the pages

Jan 1, 1890

September 20, 1917. As this meeting terminates the year's agreement under which the Engineering Foundation has appropriated its income to the National Research Council, a brief summary of what has been accomplished seems called for. The Research Council was organized Sept. 19, 1916. The Executive Committee was appointed at that meeting; since that date two other meetings of the Council have been held, one in Boston, on Nov. 13 and 14, the other in Washington on April 19. During the intervals between the meetings of the Research Council, the Executive Committee has conducted all of the business of the Council. There have been 29 meetings of the Executive Committee, 13 in New York up to the first of May, 15 in Washington subsequently, and one in Boston. The meetings in New York were devoted to the organization of the Research Council and especially to appointment of committees. At the outset, the Council had no very clear idea of the way in which it was to organize; there were several other groups of scientific men at work, among them, the Research Committee of the American Association for the Advancement of Science and the Engineering Committee of the Advisory Commission to the Council of National Defense. Time was spent in straightening out these two principal complications, both of which were satisfactorily adjusted. The upshot of these negotiations is to leave the Research Council as the only representative, national body of research men, assisting the Government. During the period up to May, the Executive Committee in New York selected carefully the personnel of some 25 principal committees, and of a large number of sub-committees; so carefully were these chosen that of the entire number, several hundred, there have been only one or two declinations. Some of the important steps in the development of the Research Council are the establishment of the Military Section, composed. of the members of the Council connected with the Government and resident in Washington. This Section put the Research Council into close contact with the most important officials of the Army and Navy. From it has grown the Washington office of the Council, and the recognition of the Research Council as the "Department of Science and Research of the Council of National Defense; " and the establishment of the Washington office after the Council of National Defense had officially recognized the Research Council. About this time Dr. Hale, Chairman of the Council, appointed Dr. Millikan to be Vice-Chairman to represent the Council in Washington, and Dr. Millikan has since then been in charge of the work of the Council. At the request of the Secretary, Dr. Millikan has prepared a brief report of some of the work of the Research Council during its first year, which is appended to this report. It shows that the Research Council has been active in much of the important work. under way in our preparations for war, and that it has rendered effective services to the Government.

Jan 12, 1917

By Henry J. Welge

The approximate methods which are now in use for calculating oil displacement from reservoirs by gas-cycling or gravity-drainage at constant gas pressure, or by water flooding, make use of fundamental relationships derived by Leverett' and Buckley and Leverett.2 The mathematical equations needed are derived by applying Darcy's law to the flowing phases, and by material balance considerations. ln general, any treatment of this type gives. for any particular exploitation time considered, a plot of oil saturation against distance in the reser-voir. The oil recovery must then be obtained by integrating in some manner the area under the plot. A useful analytical method has been derived for computing the average saturation, and hence the oil recovery. Use of this method simplifies the calculations because it makes unnecessary any numerical integrations. and even the saturation distribution plots are not needed. A further advantage of the method is that knowledge of the relative permeabilities is required only for a limited and intermediate saturation range. In both the Buckley and Leverett method and the method discussed here, a linear sand section is assumed, and in the case of gas drive the gas pressure is assumed sufficiently constant both with respect to reservoir position and time so that changes in gas density. solubility, or reservoir volume factor are negligiklle. Thus, the exploitation contemplates oil displacement as by an immiscible phase. Examples are given to illustrate how the new method can be used. INTRODUCTION AND THEORETICAL BACKGROUND This paper treats a simplified method for computing oil recovery when the oil is displaced, from the reservoir sand by a fluid which, within the limits of accuracy desired, can be assumed to be incompressible and immiscible with the oil. The method makes use of two basic relations originally developed for the case of water displacing oil. However, the case of gas displacing oil saturated with gas at a constant (or nearly constant) pressure may also be considered a displacement by an immiscible fluid. This is possible for the reason that the concentration of the gas in the oil never changes if tile pressure is fixed. consequently, any additional free gas must remain undissolved in the oil, and so must act essentially as an immiscible phase. For convenience, the cape of gas drive will be considered first. Both of the two basic relations needed refer to a linear reservoir, or one which may be somewhat idealized so that a constant cross-section is exposed to fluid flow. Further, the displacing phase is injected at one end, or face; of the reservoir, while the produced fluids are understood to emerge at one point only. which is the opposite face of the reservoir. As indicated in Fig. 1, the reservoir may he inclined by some angle 8. The first of the required equations may be derived by applying Darcy's law to both displacing and displaced phases, and subtracting the two equations. The result for water drive has been given previously, as Equation (13) of the reference by

Jan 1, 1952

Draftsman and transitman for coal mine work in Middle West. Salary $125 per month. No. 277. Technical graduate wanted for metallurgical work in experimental laboratory of large New England manufacturing concern. A knowledge of metallography of steel is essential. Practical experience is desirable but not required. No. 305. High-class man to install and take charge of a coal mining property. Must be experienced in handling labor and of good sound judgment. Work will require a man to be on the grounds practically all the time. The work is drift mining and is not gaseous. No. 306. Engineer familiar with the acid treatment and melting of cyanide precipitates; also a competent assayer. Applicant must be able to furnish good references. No. 307. Wanted-practical mining man, foreman, or superintendent for work in middle or southern Atlantic States. Salary $200 per month. No. 308.

Jan 5, 1918

The old De Beers mine, which lies northwest of Dutoitspan mine at Kimberley, was the mine which launched Cecil Rhodes (In his historical career. It was the nucleus of the De Beers Mining Co. Ltd., formed in 1880, which later became De Beers Consolidated Mines Ltd. Inactive for more than a half century, the De Beers Mine is being rejuvenated for a new era of operations. Both mines were on the Vooruitzicht farm owned by the De Beers brothers, who had bought it from the Orange Free State Government ten years previously for £50. Although the brothers sold it soon after the discovery of diamonds at Dutoitspan, they are remembered for having given their name to the foremost diamond mining company in the world. Diamonds worth nearly R180,000,000 have come from this ground, and more will be recovered when the mine is re-opened.

Jan 9, 1963

By H. W. Camp

Although the situation in the oil industry during the past year has not been conducive to large expenditures for development and research, there is little indication that such expenditures have been curtailed. While few outstanding achievements have been reported, considerable progress has been made in the development of new product,s and the adaptation of petroleum derivatives to new uses. The most important question facing the refiner today is the antiknock quality of his gasoline. This year has seen the widespread adoption of the term "octane number" as a measure for anti-knock values, and in the latter months of the year the public has been made acutely aware of this condition through competitive advertising. Gasoline is no longer priced on volatility and gravity alone, but on octane number as well; and premiums are being paid for material of relatively high octane rating. The situation has grown more and more competitive and has forced refiners continually to raise the octane rating of their regular and competitive grades, and at this writing the same situation exists for premium grades which have possessed relatively high anti-knock properties for some time. Straight-run gasoline produced from paraffin-base or semiparaffin-base crudes has an inherently low anti-knock value, and in order to convert this material to a higher quality it has been found necessary to crack an increasing percentage of the crude oil charge. By completely cracking the heavier portions of the crude and blending back with the straight-run gasoline, it has been possible to produce an average of 63 to 65 octane number gasoline on average Mid-Continent crude. This operation carried to the fullest extent does not suffice, however, and the recent and rapid development of the so-called '(reforming unit," has resulted. The straight-run gasoline fraction is cut into two parts: a light, low boiling point gasoline; and a heavy gasoline or naphtha. The latter containing the low anti-knock portions of the gasoline, is sent through a re-forming unit and subjected either to high temperature or pressure, or both, which materially increases its octane number. On average Mid-Continent the blend of low boiling point straight-run,

Jan 1, 1932

By Henry M. Howe

1. The purpose of the National Research Council as organized for war purposes is twofold, to stimulate those outside its own personnel to conduct researches of importance for winning the war and to carry on such researches through its personnel to a limited extent. How this is done is explained in Section 10. "Research" is used here in a very broad sense, including, for instance, inventing and developing mechanical and physical devices. The need of this work arises from the inevitable concentration of most of the governmental war agencies on the production and transportation of war materials of the types now adopted, as distinguished from devising new kinds of instrumentalities, such as armor, guns, aircraft, and apparatus for detecting, locating, observing, signaling, transporting, and many other military purposes. But it is important that we should devise new agencies. The war came near being won by an invention, the submarine, and its course has been affected greatly by two other inventions, tanks and aircraft. In spite of our numerical superiority victory may well be snatched from us by an invention, if we allow Germany to outstrip us in inventing. Hence the importance of the Council's work in mobilizing and organizing the services of the patriotic civilian experts throughout the country, so as to bring their powers to bear on important war problems and on inventing war devices, as an adjunct to the development work of the regular governmental bodies. 2. Status of the Council.—Though President Wilson's request caused the Council to be created in 1916 by the National Academy of Sciences under its congressional charter; though his executive order of May 11, 1918, directs the heads of "Governmental departments immediately concerned" to "continue to co-operate with it in every way that may be required;" and though the Government has contributed largely to its financial support; it is not a department of the Government but an independent research body, aiming to evolve the necessary mechanism for the novel work of systematic stimulation and guidance of research. Thus the Government, which instigated the creation of the Council, recognizes and collaborates with it, and in part supports it. The Council acts moreover as the Department of Science and Research of the Council of National Defense.

Jan 1, 1919

By J. D. Wheeler, H. W. Mathews

The increased activity in West Texas, which started in 1933, has continued through 1936 at a constantly accelerated rate. During 1936 there were 1442 wells completed in the area as compared with 700 in 1935 and 468 in 1934. Of these completions, 1313 were producers with a total 24-hr. potential in excess of 1,750,000 bbl. From among the 1442 wells, eight are considered to be discovery wells for new West Texas fields. New Fields Bennett.—The Bennett field, which added Yoakum County to the oil-producing counties of West Texas, was actually indicated as an oil-producing area during 1935, but the discovery well, Honolulu Oil Corporation, Ltd. and Cascade Petroleum Company's Bennett No. l, was not given a production test until April 1936. The discovery well made 15 bbl. per hour through 3/4-in. choke with a plugged-back total depth of 5264 ft. First oil in the hole was from 5088 to 5090 ft., which is several hundred feet below the top of Permian lime. Producing limits of the field are unknown, as the second test had not reached the pay at the close of the year. Henderson.—-To date indications are that the Henderson pool, in northern Winkler County, is the most prolific area opened during 1936. This field, which lies to the north of the old Hendrick pool, is producing from the same reef-type dolomitic lime producing in the older field. The Henderson field was opened by the completion of R. H. Henderson, J. B. Walton-Humble 1-A in April 1936 for a natural flow of 2306 bbl. per day through tubing. Total depth of the discovery well is 3049 ft. Later development has indicated the productive area to be a rather narrow zone running slightly west of north. Present area of from 1000 to 1500 acres has been proved for production. Keys and Emperor.—The Keys and Emperor pools in the belt of sand pools running across Winkler County appeared for the first time on State proration schedules during 1936. This report considers these pools as links in joining the belt of sand production across Winkler County, for

Jan 1, 1937

By E. B. Ekren, F. C. Frischknecht

Recently released results of surveys employing the slingram and turam methods show the applicability of electrornagnetics in mapping new areas containing both oxidized and unoxidized iron in the Lake Superior region.

Jan 10, 1961