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By Walter Miller

Crude oil stocks were some 10,000,000 bbl higher on June I, 1947, than at any time during 1946 but the extremely heavy refinery runs the last half of 1947 cut crude inventories to approximately the 1946 closing level of 225,000,000 bbl. Many refiners were seriously short of crude oil during the year. This shortage was reflected in numerous advances in the posted price of crude, justified in part as an incentive for more production but more generally due to competitive bidding. Some purchasers of crude, endeavoring to keep their plants running, resorted to the payment, either directly or indirectly, of premiums above the posted price. Another common practice employed by some suppliers of crude oil was to demand refined products in exchange or trade for their raw material. The refined products picture has darkened in spite of record throughputs. Stocks of gasoline and light and heavy fuel oils were uncomfortably low at the beginning of the year and were in general still lower at the close. The rationing of some products, principally gasoline, to dealers and stations? initiated during the year, gained momentum as stocks continued to diminish. The emphasis placed by the manufacturers of oil-burning equipment on the convenience and economy of heating with oil, together with the tight situation in coal, has developed a tremendous demand for burning oils. Consumption of liquefied petroleum gas for domestic and household fuel had more than doubled in 1946 over 1943, and the demand seems to be limited only by the ability of the equipment builders to furnish necessary storage. transportation, and burning equipment. The supply situation is likely to become more acute in 1948. Demand for petroleum products is being pushed to new heights not only by the unprecedented domestic market but by a sudden and drastic upswing in estimates of military and governmental requirements. Additionally, oil exports are running far below the volume requested, amounting to less than forty percent in a recent quarter, and export licenses are reportedly being approved on the basis of urgent need *only. AX recent White House release sees little likelihood that estimated requirements of the sixteen nations participating in the proposed Marshall Plan can be met in full over its projected life—1948 to 1951. Present demand dictates maintenance of refinery operations at the highest possible level and the Bureau of Mines has forecast daily average crude runs in 1948 of 5,265,000 bbl. The Economics Advisory Committee of the Interstate Oil Compact Commission recently estimated the 1948 demand for petroleum products at nearly 6 pct above 1947. They further estimate daily average crude runs of 5,375,000 bbl in 1948, some 2 pct higher than forecast by the Bureau of Mines. Projected demand exceeds supply to the extent that Capitol Hill is reportedly investigating ways of enabling oil companies to act in concert without danger of antitrust prosecution, such as elimination of crosshauls, pooling of products, and lowering of octane.

Jan 1, 1948

By Walter Miller

Crude oil stocks were some 10,000,000 bbl higher on June I, 1947, than at any time during 1946 but the extremely heavy refinery runs the last half of 1947 cut crude inventories to approximately the 1946 closing level of 225,000,000 bbl. Many refiners were seriously short of crude oil during the year. This shortage was reflected in numerous advances in the posted price of crude, justified in part as an incentive for more production but more generally due to competitive bidding. Some purchasers of crude, endeavoring to keep their plants running, resorted to the payment, either directly or indirectly, of premiums above the posted price. Another common practice employed by some suppliers of crude oil was to demand refined products in exchange or trade for their raw material. The refined products picture has darkened in spite of record throughputs. Stocks of gasoline and light and heavy fuel oils were uncomfortably low at the beginning of the year and were in general still lower at the close. The rationing of some products, principally gasoline, to dealers and stations? initiated during the year, gained momentum as stocks continued to diminish. The emphasis placed by the manufacturers of oil-burning equipment on the convenience and economy of heating with oil, together with the tight situation in coal, has developed a tremendous demand for burning oils. Consumption of liquefied petroleum gas for domestic and household fuel had more than doubled in 1946 over 1943, and the demand seems to be limited only by the ability of the equipment builders to furnish necessary storage. transportation, and burning equipment. The supply situation is likely to become more acute in 1948. Demand for petroleum products is being pushed to new heights not only by the unprecedented domestic market but by a sudden and drastic upswing in estimates of military and governmental requirements. Additionally, oil exports are running far below the volume requested, amounting to less than forty percent in a recent quarter, and export licenses are reportedly being approved on the basis of urgent need *only. AX recent White House release sees little likelihood that estimated requirements of the sixteen nations participating in the proposed Marshall Plan can be met in full over its projected life—1948 to 1951. Present demand dictates maintenance of refinery operations at the highest possible level and the Bureau of Mines has forecast daily average crude runs in 1948 of 5,265,000 bbl. The Economics Advisory Committee of the Interstate Oil Compact Commission recently estimated the 1948 demand for petroleum products at nearly 6 pct above 1947. They further estimate daily average crude runs of 5,375,000 bbl in 1948, some 2 pct higher than forecast by the Bureau of Mines. Projected demand exceeds supply to the extent that Capitol Hill is reportedly investigating ways of enabling oil companies to act in concert without danger of antitrust prosecution, such as elimination of crosshauls, pooling of products, and lowering of octane.

Jan 1, 1948

By M. F. McCarty, R. S. Olson

New organic flocculants of high-molecular weight are replacing lime, glue, and starch in liquid-solid separation. Of these synthetic materials, poly-acrylamides are outstanding. Polyacrylamides form a class of compounds varying widely in composition and activity. Separan 2610, one of the first of these flocculants' released to the mining industry in 1954, is described' as a high-molecular weight polymer of acrylamide with or without a copolymer material and with some replacement of amide by carboxylic groups. MECHANISM OF FLOCCULATION In practice, flocculation makes solids settle faster and filter better. But two opposing factors control it. The random motion that causes particles to collide favors Van der Waals' forces, which hold the particles together. The effect of zeta potential opposes this contact, and particles are mutually repelled. Flocculation can be achieved by reducing the magnitude of the zeta potential; this is the mechanism of flocculation by lime addition. The way in which polyacrylamides accomplish flocculation is not fully understood, but the action is undoubtedly comp1ex and probably varies considerably depending on the system. To begin with, the active groups of these compounds have an extremely high affinity for solid surfaces, probably by hydrogen bonding." Initially some active groups of the molecule attach themselves to the solids with a large portion of the molecule extending into the solution. Two particles can become tied together by long flocculant molecules in the following ways—by bonding between the active groups of two flocculant molecules on different particles, or by an extended molecule from one particle attaching itself directly to the surface of the other particles." These flocculant bridges prevent the particles from moving apart through random motion, but when such motion moves them together other active groups on the flocculant bridge bond to the solids, holding them in the closer position. This process is repeated until the particles are close together. Although bridging is probably a major flocculation mechanism, it is not the only phenomenon involved. Relatively neutral acrylamide flocculants reduce the magnitude of the zeta potential by increasing the viscosity of solution in the immediate vicinity of the solid surface which contains the mobile counter ions of the double layer. In other words, it moves the shear surface which bounds the zeta potential out into the solution containing counter ions which tend to neutralize the zeta potential. This effect is probably more pronounced during the initial adsorption period, before the flocculant molecules are pulled close to the solid. In some cases the slight charge of the polyacry-lamide molecule tends to neutralize a zeta potential. However, this is not a primary flocculation mechanism, as evidenced by the fact that the polyacrylamides will flocculate solids with either positive or negative zeta potential. Adsorption of polyacrylamide flocculants by a solid is substantially an irreversible reaction. Since the flocculant molecule is attached to the particle surface by many active groups of high bonding strength, desorption would require the simultaneous breaking of many bonds—an unlikely occurrence. UNIQUE PROPERTIES The irreversible adsorption of certain polyacrylamides, the flocculant's high affinity for solid surfaces and its rapid adsorption make it effective, but these unique properties require special techniques to achieve maximum flocculation. If flocculants of this type are added to a pulp as a relatively concentrated solution, the solids in the

Jan 1, 1960

By H. A. Wilmeth

IN 1955, before planning an accelerated stripping program, Chino Mines Div. began an engineering study to improve data for estimating truck haulage costs for any future haulage layout. The study aimed to develop: 1) significant unit costs, 2) a method of estimating travel time from which truck needs and future stripping rate could be determined, and 3) yardsticks of performance to measure haulage efficiencies. It was suggested that to provide significant unit costs, expense accounts should offer management two types of cost control information-unit cost yardsticks with which monthly unit costs could be compared and unit costs for estimating future expenses for any haulage layout.

Jan 5, 1958

By Robin O. Williams

AN investigation has been made of the Ni-Cr system for the purpose of elucidating certain points, namely the nature of aging in both terminal solid solutions and the nature of the phase diagram. Information pertaining to solubilities and precipitation has been obtained. Experimentation Five alloys, Table I, were arc melted in a cold copper crucible using electrolytic chromium and car-bony1 nickel, both dry hydrogen treated. These 100 g buttons were homogenized 24 hr at 1300°C in dry hydrogen and air cooled. Powders were prepared by filing or pulverizing and subsequent heat treatment was done in vacuum or helium using titanium chips as a getter. Powder of —80 mesh was filed from the 60 pct Ni alloy quenched from 1000°C and was sealed in silica under vacuum using a 250 °C outgassing. After aging as indicated in Table I1 the lattice parameters were measured on the quenched samples using the standard cos" 6 extrapolation. These parameters are considered accurate to roughly 0.0001A. In all cases chromium lines of 2.8812 ± 0.0005Å at 30°C were found. Drastic quenching from sufficiently high temperatures produced very sharp body-centered-cubic lines in the first four alloys without indications of transformations. Temperatures to 1250°C were used. Solid samples less than 1/16 in. thick were quenched in water without transformation and the powders could be adequately quenched in small helium filled thin wall silica tubing using a water quench. For those powder samples which were quenched from the two phase field the relative intensity of the body-centered-cubic lines and the face-centered-cubic lines were estimated and extrapolated to give the indicated solubility data in Fig. 1. The data for the two higher alloys were somewhat limited, the plotted points being the lowest temperature where no nickel phase was found. Neither filing, abrading, pulverizing, nor cooling to —190°C produced any new diffraction lines for solid samples quenched from the single phase region, nor did the character of the body-centered-cubic lines change Single phase body-centered-cubic powders likewise did not change on cooling to —190°C. Also, samples which had some precipitation due to inadequate quenching showed no additional changes under these conditions. The first change apparent by X-ray diffraction form samples quenched almost fast enough to prevent precipitation was the diffuseness of the body-centered-cubic lines, particularly on the low angle side, For slower cooling rates the diffuse face-centered-cubic lines appeared. Work on the large grained castings showed profuse streaking through some of the Laue spots while oscillating patterns showed broad body-centered-cubic and face-cen-tered-cubic lines as well as some new lines. For the 23.6 pct Ni alloy the new lines corresponded to 2.16, 1.96, and 1.86A and were more similar in character to the face-centered-cubic lines than the body-centered-cubic lines. Samples which were air cooled gave only face-centered-cubic and body-centered-cubic lines which were still broad. One pattern indicated that face-centered-cubic (111) plane was parallel to a body-centered-cubic (110) plane. For those samples which were examined by light microscopy there were details which were not resolved. However, varied and beautiful structures were obtained. Fig. 2 is of an alloy quenched in a helium filled silica tube from the single phase region and shows particles associated apparently with dislocations which are arranged in low angle boundaries. Finer, general precipitation has also taken place within the grains. Figs. 3 to 5 show the variety of structures produced in these alloys on continuous cooling. It appears that there are four distinct modes of precipitation as evidenced by these, figures. Annealing these structures at higher tem-peratures in the two phase field gives structures as shown in Fig. 6, which shows nickel plates in the chromium matrix which reprecipitated nickel on a much finer scale of the final quench. Lower annealing temperatures and shorter times naturally give finer plates of the nickel-rich phase. Samples of the first four alloys were annealed for appreciable times between 900º and 1250°C and gave structures like Fig. 6. The relative amounts of the two phases were measured and extrapolated to give solubility data as indicated in Fig. 1. The point at 1250°C was deduced from data of Oxx.1 These and most of the other samples were checked for ferromagnetism but none was apparent. In fact, it appeared that the magnetic susceptibilities were not more than three times that for paramagnetic chromium. Discussion In Fig. 1 it is seen that the solubility of nickel in chromium can be represented by a slightly curved line on the usual log X vs 1/T plot, These data are believed to be accurate to roughly 5 to 10º. There is only fair agreement with the data of Taylor and

Jan 1, 1958

H. G. Haemers (Ghent University, Belgium)—The authors claimed "the results of their work indicate that the metals can be arranged in a sulfation series similar in its application for selective sulfation tot the electromotive series for displacement of metals from solution". The series as stated in decreasing order for tendency of SO3 give up, is the same as that stated by free energy diagrams. Indeed, the degree of stability of a sulfate is measured by the free energy of sulfate formation out of the corresponding metal oxide and SO3. The more negative the value of the free energy (-DG) the greater the stability of the sulfate. As a second consequence this statement results in a relative aptitude for capture of SO3 by each metal oxide when brought in contact with the sulfate of other metals. Let M1 and M1 be the two metals, and — DG1 and — DG2 their free energy values at temperature T. Both sulfates are stable at temperature T if - DG1 < O and — DG2 < O. In case where — DG1 < — DG2 the stability of M1SO4 is greater than that of M2SO4, and when M1O (oxide of

Jan 1, 1958

Meeting of Oct. 23, 1914.-It was voted to take no action concerning the proposed amendments to Article VIII, Sections 2 and 3, but that they be sent to the membership, as provided by the Constitution, together with a statement of the arguments for and against the proposed changes. It was voted that the following proposed amendment, which had been unanimously approved at the annual meeting of the Institute on Feb. 18, 1914, be sent to the membership as provided by the Constitution, together with the approval of the Board of Directors of this change: Article III, Section 1, paragraph 3, sentences 2 and 3: substitute the following: "Any Member, Junior Member or Associate in arrears for two years shall be dropped from the rolls unless the time for payment is extended by the Directors. A Member so dropped may be reinstated by the Directors on paying the arrears of clues and other indebtedness with which he was charged on the books of the Institute it the time he was dropped. A Member or Associate thus reinstated shall receive the Transactions for the back year for which he pays." It was unanimously voted to extend the sincere thanks of the institute to Samuel A. Taylor, Chairman, and to each member of the several Committees of the Pittsburgh meeting, for the enjoyable and successful meeting which they brought about.

Jan 12, 1914

By Arthur B. Foote

The cams at present universally used in stamp mills lift the tappets with an involute form of curve, to which the surface of the tappet is always tangent; moreover, the line of contact between tappet and cam, if produced, would pass through the center of the stem. This is no doubt a desirable feature, but the writer has long believed that it would be much more desirable if the cam were to pick up the stamp without shock, and gradually increase the upward velocity of the stamp throughout its upward movement. The involute form of cam attempts to impart instantly a considerable upward velocity to the stamp, starting it from a state of rest, and the result is a destructive blow, a great deal of noise, and much wear and vibration. The writer has developed a form of cam which will lift the stamp pith a motion similar to that of the piston of an engine between the end and middle of its stroke; in other words, harmonic motion, from the woint of zero to maximum velocity. The curve will give this ideal motion only when the stamp is set for the exact drop for which the cam was designed, but the improved cam will not be as bad as the involute cam until the drop is reduced one-half. In other words, if a cam is designed for a 6-in. drop, it will be some improvement over the usual form of cam until the drop is only 3 in. Any cam, whatever its form, must of course lift the stamp in the same number of degrees of revolution; therefore, with this new form, since the stamp starts more slowly on its upward course, it must end up by going faster, the average speed being the same as with the involute cam. The stamp, after it is no longer in contact with the cam, keeps on going up a certain distance, which is easily calculated. It is therefore possible to hang up a stamp without a cam stick, if the fingers are not more than + in. longer than necessary to hold the tappet above, the cam. With this design of cam the surface of the tappet is not tangent to the surface of the cam throughout the lift. The possible consequences of this were studied with a full-size model, and did not seem serious, as

Jan 1, 1915

By P. A. Beck

ACCORDING to a recent hypothesis of Sully,&apos; xY. binary CT phases are characterized by 1.7 bonding 3d electrons per atom, which completely fill the first Brillouin zone. This hypothesis appears to imply that there are no empty 3d orbitals in the u phase, and that, correspondingly, this phase must be dia-magnetic, or at most weakly paramagnetic. On the other hand, Bowen and Hoar&apos; reported that a u phase extracted electrolytically from an alloy steel became ferromagnetic when cooled to about —113°C. In view of the fundamental interest of the problem from the point of view of the electron structure of the u phase, it seemed worthwhile to study the magnetic properties of massive u phase specimens of various known compositions. Sigma specimens of the following compositions were tested: 1—40 atomic pct Fe, 40 atomic pct Cr, and 20 atomic pct Mo 2—35 atomic pct Fe, 35 atomic pct Cr, and 30 atomic pct Mo 3—48.7 atomic pct Fe, 50.2 atomic pct Cr, and 1.1 atomic pct W 4—40.7 atomic pct Co and 59.3 atomic pct Cr All specimens were found to be strongly paramagnetic at room temperature, particularly alloy No. 1. At liquid nitrogen temperature, alloy No. 1 be- came ferromagnetic; the other u alloys remained paramagnetic. Even though apparently not all u alloys become ferromagnetic at liquid nitrogen temperature, in view of their strong paramagnetism it is probable that the electron structure proposed by Sully is not correct. Similar qualitative studies were made with the p, P, and 8 phases." A p phase specimen of 57.2 atomic pct Co and 42.8 atomic pct Mo; a P specimen of 19.9 atomic pct Cr, 37.8 atomic pct Ni, and 42.3 atomic pct Mo; and a 8 specimen of 50.4 atomic pct Ni and 49.6 atomic pct Mo were tested at room temperature, and all were found to be paramagnetic, although considerably weaker than the u phase specimens described above. A test at liquid nitrogen temperature gave similar results for all specimens; none became ferromagnetic. Thanks are due to D. K. Das for preparing several of the alloys and to Pol Duwez of California Institute of Technology for kindly loaning four specimens of cr alloys. References 1 A. H. Sully: The Sigma Phase in Binary Alloys of the Transition Elements. Journal Inst. Metals (1951) 80, p. 173. - K. W. J. Bowen and T. P. Hoar: Low Temperature Ferromagnetism of Sigma Phase in an Alloy Steel. Research (1950) 3, p. 484. 3 S. Rideout, W. D. Manly, E. L. Kamen, B. S. Lement, and P. A. Beck: Intermediate Phases in Ternary Alloy Systems of Transition Elements. Trans. AIME (1951) 191, p. 872; Journal of Metals (October 1951).

Jan 1, 1953

By Berlen Moneymaker

THE development, within recent years, of core drills capable of drilling holes up to 72 in., or even more, in diameter, has made possible an entirely new and valuable method of geologic exploration, Although little used until recently as an exploratory tool except in the United States, by the Tennessee Valley Authority and the Corps of Engineers of the U. S. Army, for the exploration of damsites, the large-diameter core drill may be used to good advantage in other types of geologic exploration. Its princi-pal utility is that of supplementing, rather than replacing, other means of exploration. Although core is frequently recovered intact, the greatest advantage of large-diameter drilling is that the holes produced are large enough to be entered by the geologist and engineer, and thus afford an excellent means of examining undisturbed rock. The walls of the holes are smoothly cut, and in some rocks nearly or quite polished, so that the most minute details of structure and stratigraphy are clearly disclosed. Such features as faults, joints, bedding planes, weathered "seams," and beds or layers of soft materials, which are not always amenable to disclosure by cores recovered from small-diameter holes, are conspicuously displayed in the walls of large holes. Frequent reference to the drilling of large-diameter holes is made in engineering literature, but comparatively little emphasis has been placed on their value in geologic investigation. It is, therefore, intended that the present paper acquaint the geologist, as well as the engineer, with the large-diameter core drill and the technique involved in its use, and also with its advantages, disadvantages and limitations as an implement of geologic exploration.

Jan 1, 1938

By B. Thomas Mansbach

INTRODUCTION The Overseas Private Investment Corporation ("OPIC") is a U.S. Government agency mandated to promote the economic development of the less developed countries ("LDCs") by assisting U.S. private investment in the Third World. Generally, investment decisions turn on the optimism or pessimism of the private sector&apos;s financial analysis of a project, with market price of product a major unknown in a very chancy set of projections. Discussions with American mineral companies, however, show that, more often than not, in developing country projects it is the political risks of investing in mineral exploration and extraction that pose the most serious deterrent to investment. In several of the projects described here, investments would not have been made if OPIC had not been involved providing support to the project sponsors and their funding sources. Clearly it is not OPIC&apos;s business to promote U.S. investment in a project which is not commercially viable, but OPIC&apos;s programs can neutralize the political uncertainties which act as disincentives to investment in otherwise commercially viable projects. That is to say, OPIC&apos;s programs are designed to reinforce market decisions and not distort them. Although OPIC is an independent agency of the U.S. Government, it is managed by a Board of Directors, the majority of whom come from the private sector. This, coupled with the statutory requirement that it be self-sustaining and operate with due regard for the principles of prudent risk management, requires that it operate on a business-like basis. Although established as a development agency, to the business public OPIC is both an insurance company and a lending institution, with two major programs which are available to U.S. investors in the minerals sector: its political risk insurance program and its finance program. Each has been specially tailored to the meet needs of the mining industry. The insurance program provides coverage against four basic types of political risk: Currency Inconvertibility, Expropriation, loss caused by War, Revolution and Insurrection and Interference with Operations as a result of an act of War, Revolution or Insurrection. Coverage against the risks of Civil Strife can be added to both War, Revolution and Insurrection coverage and Interference with Operations. Inconvertibility coverage provides protection against a deterioration in an investor&apos;s ability to convert local currency into U.S. dollars. This deterioration can be the result of either active or passive delays. Active delays consist of a change in exchange laws or regulations that leads to inconvertibility delays of 30 days or more. For example, if the exchange regulations at the time of contract execution allow an investor to transfer earnings equal to 18% of its registered capital per annum and the government of the host country later changes the law to allow conversion of only 12%, the insured would convert the 12% transferable under the new exchange regulations with the government foreign exchange authorities, delivering the remaining 6% to OPIC for conversion at 99% of the then prevailing rate of exchange. (OPIC does not cover devaluation risks.) Upon delivery of the local currency to OPIC, normally at the U.S. Embassy in the project country, the insured&apos;s account in the U.S. would be credited with dollars. Delays can also result from what is termed passive blockage, which includes administrative delays of more than 60 days (sometimes longer) caused by the bureaucratic tie-ups or pigeonholding of transfer requests, as well as delays suffered simply because the government of the host country does not have sufficient foreign exchange. The transfer procedure is the same as with active blockage - the local currency is delivered to OPIC in the project country and OPIC provides dollars in the United States at the then prevailing rate of exchange. The second coverage -- Expropriation -protects not only against the loss of the investment due to the well-known risks of expropriation, nationalization or confiscation by the host government, but also against

Jan 1, 1985

By Bruce A. Kennedy

Lufthansa flight 497 roared down the runway and climbed rapidly through the early morning mist hanging over Pudahuel airport and the city of Santiago, Chile, into the brilliant sunlight above the clouds. As the plane banked onto course for Lima, Peru, we got what was possibly our last look at the beautiful snowclad mountains that ring Santiago. To the northeast was the massive hump of Aconcagua, the highest mountain in the Southern Hemisphere, wreathed in clouds and virtually looming over Rio Blanco, the new mine put into production by Cerro de Pasco just one short year before. Almost a thousand miles to the north lay the massive open pits of Chuquicamata and Exotica, and a little closer to Santiago the El Salvador mine. Behind to the southeast, clinging to the steep slopes of the Andes, was the large and awe-inspiring El Teniente mine at Braden. These mines, once the bastions of such companies as Anaconda and Kennecott, had a new owner-the Government of Chile. On the plane were a number of people who had spent a large part of their lives in Chile operating these mines and plants, and who now were suddenly faced with the necessity of starting new lives somewhere else. To them, this was their last look at the country which not too long ago was their home, a bittersweet moment of reminiscence and a time for questioning what the future held.

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 Oct. to Nov. 10, 1915: Lester S. Thompson, New York, N. Y. Arthur L. Sweetser, Boston, Mass. William Reed, El Oro, Mexico. Dorsey A. Lyon, Salt Lake City, Utah Heinrich Ries, Ithaca, N. Y. D. W. Blaylock has resigned his position with the St. Joseph Lead Co., Bonne Terre, Mo., and has accepted the position of division engineer for the Big Creek Coal Co., of Chicago, at Harrisburg, Ill. R. B. Lamb announces the removal of his office to Room 1809, 43 Exchange Place, New York, N. Y. C. C. Sanders has taken a bond and lease on the Red Mountain group of 34 mining claims (copper), Patagonia, Ariz., and has commenced extensive development.

Jan 12, 1915

By Robert F. Griffith

In 1948 when the U.S. Bureau of Mines began the investigation of domestic monazite placers for the Atomic Energy Commission, deposits of this type amenable to large-scale operations were unknown in the U. S. Intensive search for such deposits had not been carried out in the past. Problems to be met included scarcity of men with placer experience and need for development of new exploration, evaluation, and analytical procedures. As a result of the exploration program three dredges have gone into operation in one area in Idaho and another dredge is operating in South Carolina. Search for Deposits In the search for areas to be investigated for monazite, the first step was a thorough study of all available literature reporting occurrences of the mineral. Initial work was guided largely by many reconnaissance reports prepared by the U. S. Geo- logical Survey and the AEC. As the work progressed many new deposits, not mentioned in the literature, were called to the attention of USBM engineers by prospectors who had noted the presence of the yellow, heavy sand while prospecting for placer gold. Every prospector was given an attentive ear.

Oct 1, 1955

By Louis Doremus Huntoon

HAVE been asked many times by financial men in New York as to the best way of securing an interest or control of a gold mine in Canada. It must be understood at the start that prospectors and early owners will not sell a 100 per cent interest. They not only retain from 10 to 25 per cent interest, depending upon the work done, but usually demand more or less cash to reimburse them for expenses. These conditions are accepted by Canadian capital and operating mines looking for new properties. The winter is not a hindrance to work but may be of great advantage. The overburden of soil and gravel is generally wet and most difficult to trench in the summer time especially if at all deep. The snow also permits easy transportation of freight. Properties distant from rail transport all of their machinery and supplies during the winter months.

Jan 1, 1933

Following closely Marcona Corp.&apos;s announcement of its new Marconaflo process for transporting mineral slurries by ship (see pp. 96-97, Sept. 1969 [ ]), Midland-Ross Corp. (M-R) now heralds its metallized iron pellet process which supplements Oregon Steel Mills1 (Oregon Steel) new Portland, Ore., plant. Harry J. Bolwell, president of M-R describes the company&apos;s M-R Pellet as "the most exciting advance in steelmaking in a decade, one which will profoundly affect the industry." In fact, other knowledgeable industry spokesmen believe that with these developments the mini-steel plant era is now here and that this technical development along with the Marconaflo process will revolutionize iron ore shipments and steelmaking. The M-R president predicts that electric furnaces can account for 20% of the annual U.S. steel production by 1975, compared with 14% at the present time because of these developments.

Jan 12, 1969

1944 WALTER HULL ALDRIDGE New York, N Y 1946 PETER M ANDERSON Johannesburg, South Africa 1946 CHARLES CAMSELL Ottawa, Ont, Canada 1946 CHARLES AUGUSTUS CARLOW Fife, Scotland 1946 CECIL H DESCH London, England 1946 WILLIAM FRASER London, England 1917 HERBERT HOOVER New York, N Y 1941 DANIEL COWAN JACKLING San Francisco, Calif 1939 HENRY KRUMB New York, N Y 1942 ESSINGTON LEWIS - Melbourne, Vic , Australia 1921 C MCDERMID London, England 1944 WALTER C MENDENHALL Washington, D C 1942 PAUL DYER MERICA New York, N Y 1913 EZEQUIEL ORDONEZ Mexico City, Mexico 1938 A M PORTEVIN Paris, France 1937 GEORGE S RICE Washington, D C 1934 T A RICKARD Victoria, B C, Canada 1946 JOHN R SUMAN Houston, Texas 1946 WONG WEN-HAO Chungking, China

Jan 1, 1952

By Edgar Kendall

A KNOWLEDGE of the fundamental principles of locating, sampling, testing and evaluating materials is essential in prospecting for mineral aggregates. In this discussion, mineral aggregates will be considered sand, gravel, crushed stone and slag that are used as materials of con-struction. The quantity of mineral aggregates produced in the United States during the year 1935 for such purposes was roughly 165,000,000 tons, about 60 per cent of which was sand and gravel, 37 per cent crushed stone and 3 per cent crushed slag. The total value of this material was approximately $100,000,000. It is apparent therefore that the prospect-ing for suitable mineral aggregates is of considerable economic importance. In prospecting for mineral aggregates, the methods employed are the same whether the organization is large or small. In the large organiza-tion there may be available geologists for locating sources of supply, a land acquisition department to arrange for the necessary options or permits, engineers to do the sampling, a laboratory for testing, and a board of consulting materials engineers to make the final selection. Even small organizations must follow the same general procedure, though the respon-sibility for the selection of aggregates may rest with one man, who may or may not be an engineer, but who must depend entirely upon his own judgment.

Jan 1, 1939

By F. C. Hull

The grain size of a metal or alloy is one of the most important factors determining its properties. In steels, for example, grain size affects hardenability, toughness and machinability; in brasses, grain size is related to hardness and deep-drawing quality. In the field of heat-resistant alloys, grain size has a marked effect on ductility, creep and endurance strength. In order to determine these effects, as well as to control the properties of materials, many accurate and rapid measurements of grain size must be made. This paper presents a new and improved method for the estimation of grain size. Usual Methods OF EvaluatiNg Grain Size A frequetly used method of estimating grain size is that of comparing the image of a polished and etched specimen on the ground-glass screen of a metallographic microscope with standard grain-size charts. Several types of standards are available for use with different classes of microstructures. Geometric Grids.—The Metals Handbook&apos; has a series of hexagonal grids ranging in size from ASTM No. I to 8. Idealized Grain Networks.—Idealized grain.boundary networks for ASTM grain sizes I to 8 are included in the American Society for Testing Materials Tentative Standard E 19 - 39 T, standard Micrographs & Metals Handbook and ASTM Tentative Standard E19-3gT contain micrographs of hypo-eutectoid and hypereutectoid steels ranging in grain size from No. I to 8. The grain size of annealed brass (diameter of the average grain in millimeters) is obtained by comparison with 10 micrographs of varying. grain size in ASTM Tentative Standard E 2-39 T. A handicap to accurate evaluation of grain size by this method is the fact that it is difficult to compare photographs in a dimly lighted room with the image on the ground-glass screen, or, if the general illumination is increased so that the printed standards may be clearly seen, the contrast of the image of the unknown is decreased. It is easier to estimate grain size by comparing a micrograph of the unknown with the grain-size standards. However, photographing every specimen on which the grain size is desired is too costly in time and materials to be practicable. For hardened steels, the Shepherd or Jernkontoret fracture grain-size standards are very accurate and useful, but this method obviously cannot be applied to ductile alloys such as brass, stainless steels and austenitic heat-resistant alloys. Jeffries&apos; method for grain-size measurements consists of counting the number

Jan 1, 1948

By F. C. Hull

The grain size of a metal or alloy is one of the most important factors determining its properties. In steels, for example, grain size affects hardenability, toughness and machinability; in brasses, grain size is related to hardness and deep-drawing quality. In the field of heat-resistant alloys, grain size has a marked effect on ductility, creep and endurance strength. In order to determine these effects, as well as to control the properties of materials, many accurate and rapid measurements of grain size must be made. This paper presents a new and improved method for the estimation of grain size. Usual Methods OF EvaluatiNg Grain Size A frequetly used method of estimating grain size is that of comparing the image of a polished and etched specimen on the ground-glass screen of a metallographic microscope with standard grain-size charts. Several types of standards are available for use with different classes of microstructures. Geometric Grids.—The Metals Handbook&apos; has a series of hexagonal grids ranging in size from ASTM No. I to 8. Idealized Grain Networks.—Idealized grain.boundary networks for ASTM grain sizes I to 8 are included in the American Society for Testing Materials Tentative Standard E 19 - 39 T, standard Micrographs & Metals Handbook and ASTM Tentative Standard E19-3gT contain micrographs of hypo-eutectoid and hypereutectoid steels ranging in grain size from No. I to 8. The grain size of annealed brass (diameter of the average grain in millimeters) is obtained by comparison with 10 micrographs of varying. grain size in ASTM Tentative Standard E 2-39 T. A handicap to accurate evaluation of grain size by this method is the fact that it is difficult to compare photographs in a dimly lighted room with the image on the ground-glass screen, or, if the general illumination is increased so that the printed standards may be clearly seen, the contrast of the image of the unknown is decreased. It is easier to estimate grain size by comparing a micrograph of the unknown with the grain-size standards. However, photographing every specimen on which the grain size is desired is too costly in time and materials to be practicable. For hardened steels, the Shepherd or Jernkontoret fracture grain-size standards are very accurate and useful, but this method obviously cannot be applied to ductile alloys such as brass, stainless steels and austenitic heat-resistant alloys. Jeffries&apos; method for grain-size measurements consists of counting the number

Jan 1, 1948