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By R. M. Bird

FEW persons outside of the foundry trade have any conception of the great variety of sands now regularly specified and furnished, nor of the differences in foundry practice frequently resulting from apparently minor changes in sands. Conditions in each locality where the sands are mined and prepared necessitate special equipment designed to perform the work efficiently. The description that follows of the foundry sand producing operations is typical of the areas in New York and New Jersey, and particularly refers to the operations of the George F. Pettinos Co.

Jan 1, 1926

By E. DeGolyer

WAR has wrought sharp and sudden changes in the pattern of the oil industry. The most obvious and most striking of such changes have been in the fields of transportation and refining. A third of the world's total oil production formerly started to market, tanker-borne, over the waters of the Gulf and Caribbean. Most of this oil went to our North Atlantic ports, supply points for the world's greatest consuming center. This tremendous traffic, disrupted by the loss of tankers as a result of requisition for military purposes and by the activity of enemy submarines, has had to be substituted largely by such lines of supply as could be improvised without loss of too much time. No single solution for this gigantic problem has been found nor is it likely to be entirely solved for some time to come. It has been solved in part, however, by rearrangement, reversals, and patching up of existing pipe-line systems; by overland transport of crude and products in tank cars on a scale never before attempted; by barging over inland waterways; and through the construction at long last of the "big-inch" line, the first leg of which is just being put into operation as far as Norris City, III. The tank-car traffic alone, reaching a peak of deliveries of 856,710 barrels per day into District 1 during the week ending Sept. 19, 1942, and accomplished at an expense of millions of dollars in extraordinary transportation costs, defrayed by the Defense Supply Corp. and by the mobilization of tank cars from all over the nation, is a story worth the telling but by some of those who directed it.

Jan 1, 1943

By WOOLSEY MCA JOHNSON

INDEPENDENTLY of the recognized chemical reactions involved in the production of metallic zinc, the process is affected by physical conditions in efficiency, and by commercial as well as technical economy. To offer some observations concerning these conditions is the purpose of the present paper. Among the important elements of this problem is the physical nature of the particles constituting the mass of zinc oxide to be reduced. This may be the result, either of the manner of the original deposition of the mineral, or of the treatment to which it has been subjected in the roasting-furnace. The physical character of the reducing-agent is another important factor, since the carbon of some coals is much more active in reduction than that of others. The degree of fineness, whether of ore or coal, or both, likewise plays a significant part. These factors, together with the physical admixture of foreign substances with the ore, may give rise also to chemical "side-reactions," sometimes hindering or retarding, and sometimes accelerating, the reduction. Finally, thermal conditions, including the relative conductivity of the materials, deserve to be taken into account. In firing a furnace with retorts charged with a mixture of roasted ore and coal, the first reaction is naturally the boiling-off of the contained water ; the next is the distillation of the light hydrocarbons from the coal; the next is the reduction of the iron oxide to protoxide and sub-oxide successively, and then to metallic sponge; and the final reaction is the reduction of the zinc oxide in the ore by the carbon to metallic zinc. This reaction commences at 1,022° to 1,060° C., according to the physical nature and condition of the coal and ore. Since the retort and the charge are far from being good con-

Sep 1, 1907

By Tilden Cummings

The extractive mineral industries share a number of common characteristics and basic problems which are completely different from those associated with manufacturing and mercantile operations. These industries now supply about 95% of the inanimate energy consumed in this country, and share with agriculture in providing virtually all of our basic raw materials. Mineral producers, like farmers, are subject to the economic hazards of fluctuating markets and prices. Unlike farmers, however, they cannot renew the productivity of the earth, but must seek continually for new sources of supply. The necessity for exploration and development of new reserves, to replace those used up by production, introduces additional factors of economic risk. These operations require the expenditure of large amounts of capital, often well in advance of any assurance of profitability. Commercial banks that understand these special problems can provide a variety of constructive financial services to the mineral industries. The history of cooperation between banks and mining enterprises has yet to be written, but there is every indication that it would encompass a period of hundreds of years. Records refer to depository and lending services by the early European private bankers involving precious metals and jewels. Many of the exploratory voyages to the Far East and the New World were organized with the financial backing of wealthy syndicates, some of which also provided banking services, in the hope of finding new sources of gold and other precious minerals. In the United States many large banks are closely identified with the development of some of the larger mineral deposits such as the Mesabi Range and the gold fields of California.

Jan 5, 1965

COUNCIL OF ECONOMICS OF AIME Formerly Mineral Economics Division Established as a Division December 15, 1948 Established as a Council February 26, 1957 Franz R Dykstra, Chairman Paul Schultz, Vice-Chairman A J Phillips, Vice-Chairman Douglas Donald, Vice-Chairman J S Vanick, Contact AIME Director A H Lindley, Jr, Secretary-Treasurer Lehman Brothers 1 William Street New York 4, N Y COUNCIL OF EDUCATION OF AIME Formerly Mineral Industry Education Division Established as a Division January 15, 1932 Established as a Council February 26, 1957 0 Cutler Shepard,Chairman Lysle E Shaffer, Vice-Chairman John C Calhoun, Jr, Past Chairman J C Kinnear, Jr, Contact AIME Director J D Forrester, Secretary-Treasurer College of Mines Univ of Arizona Tucson, Arizona

Jan 1, 1958

By Walter Miller

A surprising development during the year was the continued high demand for petroleum products and the high level of crude oil charges to the stills. Generally speaking, the petroleum industry during 1946 succeeded in producing a greater quantity of crude oil and petroleum products than in any of the war years, and considerably exceeded the production of any prewar year. Daily crude still charges averaged between 4,700,000 and 4,800,000 bbl per day for 1946 and about equaled the 1945 record, although most pessimistic 1945 guesses, predictions, or fears ranged, for 1946, from only 3,900,000 to 4,400,000 bbl per day. In spite of the high crude charge to the stills, total stock of crude oil was higher at the end of the year by some 7,000,000 to 8,000,000 bbl. A similar story holds regarding stocks of the principal refined products. Gasoline on hand at year's end was two to three million barrels lower, and was considered low for the expected demand during the coming high consuming season, while stocks of light and heavy fuel oils, although some higher than a year previous, hardly reached a comfortable level. The trend in gasoline of high octane number, which has resulted in a marked rise in. the antiknock quality by the end of 1945 (five or six numbers higher than during the war and one number higher than the prewar quality of civilian motor gasoline of 1941) was abruptly arrested by an acute shortage of metallic lead for manufacturing tetraethyl lead. Government action in the form of lead price control, rationing, and the setting of octane ceiling specifications to conform to the reduced ethyl lead compound available were enforced until abrogated at the end of the year. It will be interesting to see how rapidly the octane levels will resume the rising trend, as more metallic lead slowly becomes available for making greater quantities of ethyl lead compound. As octane quality rises over present levels the disadvantage of the refiner without catalytic cracking equipment will increase. Gasoline made by catalytic cracking, without addition of ethyl lead, approximates 77 octane by the official ASTM Motor Method test, compared with 66 for gasoline generally similar in volatility made by the older thermal cracking operation. Catalytic gasoline shows an even greater improvement in the Research octane number, the comparison being roughly 86 Research versus 71 Research octane for the thermal cracked product. This higher differential in Research octane is credited by many, although not universally so, as contributing to better road performance, and consequently resulting in a more desirable product marketwise. In some parts of the country a premium of roughly one fourth cent per gallon is now being paid for gasoline with higher Research octane made possible by including catalytic cracked product in the final blends. If such price differentials in favor of catalytic gaso-

Jan 1, 1947

By Walter Miller

A surprising development during the year was the continued high demand for petroleum products and the high level of crude oil charges to the stills. Generally speaking, the petroleum industry during 1946 succeeded in producing a greater quantity of crude oil and petroleum products than in any of the war years, and considerably exceeded the production of any prewar year. Daily crude still charges averaged between 4,700,000 and 4,800,000 bbl per day for 1946 and about equaled the 1945 record, although most pessimistic 1945 guesses, predictions, or fears ranged, for 1946, from only 3,900,000 to 4,400,000 bbl per day. In spite of the high crude charge to the stills, total stock of crude oil was higher at the end of the year by some 7,000,000 to 8,000,000 bbl. A similar story holds regarding stocks of the principal refined products. Gasoline on hand at year's end was two to three million barrels lower, and was considered low for the expected demand during the coming high consuming season, while stocks of light and heavy fuel oils, although some higher than a year previous, hardly reached a comfortable level. The trend in gasoline of high octane number, which has resulted in a marked rise in. the antiknock quality by the end of 1945 (five or six numbers higher than during the war and one number higher than the prewar quality of civilian motor gasoline of 1941) was abruptly arrested by an acute shortage of metallic lead for manufacturing tetraethyl lead. Government action in the form of lead price control, rationing, and the setting of octane ceiling specifications to conform to the reduced ethyl lead compound available were enforced until abrogated at the end of the year. It will be interesting to see how rapidly the octane levels will resume the rising trend, as more metallic lead slowly becomes available for making greater quantities of ethyl lead compound. As octane quality rises over present levels the disadvantage of the refiner without catalytic cracking equipment will increase. Gasoline made by catalytic cracking, without addition of ethyl lead, approximates 77 octane by the official ASTM Motor Method test, compared with 66 for gasoline generally similar in volatility made by the older thermal cracking operation. Catalytic gasoline shows an even greater improvement in the Research octane number, the comparison being roughly 86 Research versus 71 Research octane for the thermal cracked product. This higher differential in Research octane is credited by many, although not universally so, as contributing to better road performance, and consequently resulting in a more desirable product marketwise. In some parts of the country a premium of roughly one fourth cent per gallon is now being paid for gasoline with higher Research octane made possible by including catalytic cracked product in the final blends. If such price differentials in favor of catalytic gaso-

Jan 1, 1947

The annual report of the Secretary of the Southern California Local Section for the year ending May, 1919, says that the Section was called upon to give all the assistance possible for the different Liberty Loan drives, for the Red Cross drives and not only in the canvass of our membership, but the canvass of all of the mining companies represented in this city. The committee on the Red Cross drive on which we were represented raised a larger proportion of the total amount than any other in the city. The subscriptions for Liberty Bonds from the members of our' Section that were credited to the Committee of the Joint Technical Societies exceeded in amount the subscription from the members of all the other technical societies combined. Members of our Section slid splendid and efficient work throughout the first half of the year at the Red Cross headquarters in this city, and under the leadership of A. B. W. Hodges and F. B. Close, systematized the work of handling the enormous quantity of material that passed through that organization. Mr. E. A. Montgomery directed the canvass of the mining companies of this city in the bond drives, and the Executive Committee did its part in solicitation among the mining engineers. The Section, together with the local sections of the American Chemical Society, American Institute of Architect, American Institute of Electrical Engineers, American Society of Civil Engineers, American Society of Mechanical Engineers, and the local Engineers and Architects Association, forms what is called the Joint Committee of the Technical Societies. of Los Angeles. The honor of having the first president of this combined organization of engineers was given to us with, the election of Mr. Seeley W. Mudd. Upon Mr. Mudd's entering the service, Mr. George A. Daman of the Electrical Engineers was elected to the position and served splendidly during the latter part of the year. It devolves upon this Section to be represented upon this Joint Committee by three members, and it is our duty to supply a speaker once in six weeks to address the engineers in attendance at the weekly luncheon. During the year not a few of the most prominent men of the engineering professions have spoken upon subjects of the greatest interest to us all. Had it not been for the organized team work in the engineering profession available through this Joint Committee, there would have undoubtedly been passed in the recent session of the legislature of this state a bill for licensing and registering all professional engineers in this state, which, in the opinion of your Executive Committee and a large proportion of the membership of this Section, would have fallen far short of either protecting the engineer or protecting the public from impostors. That the public is awakening to the importance of what our National Society represents in the profession of mining engineering can be well inferred from the increasing number of inquiries your Secretary receives regarding the reputation of mining engineers. The necessary qualifications which a membership in the Institute requires and the membership of an engineer in this National Organization is more and more a criterion as to the ability of an engineer who represents himself as such, to the general public.

Jan 9, 1919

By Edward H. Robie

PONCA CITY proved an ideal selection as a place of meeting for the Petroleum Division this fall. The accommodations at the Conoco Club were just what was required for such a gathering; the committee having the arrangements in charge functioned with the efficiency of veterans and the enthusiasm of neophytes; and the members and guests followed the speakers with close attention, entered the subsequent discussions with gusto, and divulged the "low-down" at private conferences. No one minded the drizzling rain on the first day, which only served to keep up the attendance in the auditorium; the weather then cleared up in time for a group picture before the gathering went their separate ways.

Jan 1, 1932

By C. L. Meyers, A. V. Levy, G. Y. Onoda, R. J. Kotfila

This paper presents the hypothesis that solid-solution hardening of regions in the order of tens of angstroms thick along grain boundaries is the most important mechanism controlling the ductile -brittle transition behavior of poly crystalline bcc refractory metals. Further, a physical model is developed and a general equation is derived to describe the dependence of the solute concentration at grain boundaries on temperature, nominal impurity concentration, thermal treatments, vain size, and prior plastic deformation. Analytical curves of the solute concentration at grain boundaries us temperature, calculated by means of the derived equation, are found to have the same general form as curves of ductility us temperature plotted from experimental data. Senziquantitative relationships between the transition temperature and metallurgical variables can he determined by using the physical model. The room-temperature brittleness of the poly-crystalline refractory metals (tungsten, molybdenum, and chromium) is a result of their high ductile-brittle transition temperatures. Recently studies on single crystals have revealed that, when sufficiently pure, these crystals have much lower transition temperatures than polycrystalline specimens of similar purity.'-3 For example, the transition temperature (measured by reduction in area in tensile tests) for very high-purity tungsten crystals has been reported to be as low as -50°F whereas polycrystalline specimens of similar purity had a transition temperature near 400" ~.' These results suggest that the ductile-brittle transition behavior of these polycrystalline metals can be attributed principally to the influence of grain boundaries on plastic flow and fracture. This paper contains a discussion of the manner in which grain boundaries influence the ductility of the poly-.crystalline bcc refractory metals and proposes that the segregation of impurities to grain boundaries is the most important mechanism for controlling the ductile-brittle transition behavior of these metals. Further, this paper contains an analysis of the effect of the compositional and structural variables on the grain boundary-ductility relationship, and introduces a semiquantitative model that can provide a foundation for more theoretical treatment to describe the influence of these variables on ductile-brittle transition behavior. PHYSICAL MODEL FOR PREDICTING DUCTILE-BRITTLE TRANSITION BEHAVIOR Grain Boundary Segregation of Impurities. Based on their own observations and on theoretical grounds, numerous investigators have suggested that impurities segregate to the grain boundaries. Such segregation would be expected because regions exist where both large and small foreign atoms fit with less strain than within the undistorted crystal structure. Therefore, the concentration of impurities should be higher at boundaries than within the grain body. TO estimate the degree (i.e., the ratio of grain boundary to nominal bulk concentration) to which an interstitial solute tends to segregate at boundaries within a solvent metal, the solubility rather than the size misfit could be used as a guide because solubility expresses the joint effect of both elastic and electronic factors.5 The solubilities of interstitial elements such as carbon, hydrogen, nitrogen, and oxygen are low in the group V-A metals and very low in the group VI-A metals.6 These low solubilities suggest that segregation to grain boundaries should occur for each of these solutes in both refractory metal groups. The difference between the ductility of single-crystal and polycrystalline bcc refractory metals can be described in terms of two distinct effects.4 The first of these is the general observation that grain boundaries hinder slip within grains and slip transfer between grains, and the second is that deformation is more complex in each grain of a polycrystalline specimen than it is in a single crystal. Mc Lean has pointed out, furthermore, that strong slip-hindrance effects at grain boundaries should occur in metals having strong segregation of impurities to grain boundaries. Therefore, the effect of grain boundaries on the hindrance of slip is expected to be the dominating influence on the ductile-brittle transition behavior of these polycrystalline refractory metals. cahn5 has suggested that temperature and solute mobility should influence solute equilibrium segregation at grain boundaries, and Fig. 1 illustrates

Jan 1, 1965

By J. Robert Van Peli

IT was a strange but highly fruitful marriage-that union of hardy explorers, seeking the rich treasures of copper in the Lake Superior wilderness, with Boston's aristocracy of brains, capital, and enterprise. This historic wedlock, which has continued happily to the present day, was the means by which the wealth of Lake Superior's copper was won for the use and benefit of an expanding America. One branch of this family tree, the western branch, begins with prehistoric Indian miners, embraces the early French explorers of the Upper Lakes, and finally includes the British and American pioneers who reduced the vague rumors of copper to known fact and actually began the mining of copper in the wilderness. The other branch, the New England line, begins

Jan 1, 1948

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'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's business to promote U.S. investment in a project which is not commercially viable, but OPIC's programs can neutralize the political uncertainties which act as disincentives to investment in otherwise commercially viable projects. That is to say, OPIC'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'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'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 J. L. Perry

FOR many years, you and your fellow members of the American Institute of Mining and Metallurgical Engineers have devotedly and ably applied yourselves to the art of making iron and steel. having foremost in your minds the conservation of raw materials, suitable and efficient facilities, economical processes, and improved quality of product. For the past three strenuous years you have contributed wholeheartedly to meeting the problems of increased production. You have conducted scientific and technical investigations and research, recommended experiments. and gathered all the available and valuable information possible to gain the desired objectives. You have had many obstacles and difficulties to overcome. In the early days of your organization, there was some lack of co-operation from the industry itself-perhaps, for example, some failure to recognize the mutual advantages of free exchange of experiences and information. But regardless of any hindrances, you have made many and valuable contribution which have tended to make iron and steel manufacture leas of an art and more of a science.

Jan 1, 1944

By R. E. Radabaugh, J. M. Brown, J. S. Merchant

The Gilman district is on the northeast flank of the Sawatch Range in central Colorado. It has yielded a total of 10,000,000 tons of ore having a value of over $250,000,000. Paleozoic sediments intruded by a Tertiary quartz latite sill and unconformably overlying Precambrian intrusives and metasediments comprise the country rock of the area. The sediments strike northwesterly and dip 8° to 12° northeasterly. Structures in the Precambrian are related to the Homestake shear zone of the Colorado mineral belt. Only minor folding and faulting occur in the sediments. The principal ore bodies are massive sulfide replacement deposits in carbonate rocks. They consist of long, pipe-like mantos in the completely dolomitized Mississippian Leadville Limestone and funnel-shaped chimneys of copper- silver ore cutting across the Mississippian and Devonian strata. Mineralization is continuous from the chimneys into the mantos. The principal ore bodies are roughly in the shape of a four-tined fork which points up dip. Smaller manto deposits occur in the Cambrian Sawatch Quartzite, and fissure veins are present in the Precambrian rocks. The principal minerals in the mantos are marmatite and galena in a gangue of pyrite and manganosiderite. The chimneys consist of a central core of pyrite with erratically distributed chalcopyrite, tetrahedrite, freibergite, and occasional galena with a shell of zinc ore on the outer margin. Both the chimneys and the mantos are surrounded by imperfect shells of manganosiderite and sanded dolomite. The mineralization is of Laramide age. Hydrothermal alteration affects all rock units to varying degrees. Clay mineral alteration halos occur around the ore bodies. Hydrothermal solutions have developed sanded rock, rubble filled channels, and banded zebra textures, principally in the Leadville Limestone. Structural control of the ore bodies is not well defined. Both the location of the district and the chimneys are probably related to basement structures. The mantos are largely controlled by stratigraphic factors and a pre-Pennsylvanian karst topography in the Leadville Limestone, which were modified by hydrothermal activity, and by weak zones of northeasterly trending faults.

Jan 1, 1968

By John J. Collins

The plight of the Japanese mining business is pitiful. Coal mines were given the highest priority for all materials they needed, yet between the end of the war and June 1948, the government was obliged to subsidize them to the extent of 22 billion yen, this being the difference between the consumer's price and the producer's price. Most of the metal mining companies have been operating at only one fifth to one third of war-time production rates, and financial losses have been terrific. The chief difficulties have been a plethora of office workers and a dearth of equipment, supplies, and miners. The principal material needs at metal mines are steel rails. cars, plates, nails, rubber hoses, and belting, to say nothing of modern core drills which are totally lacking. Until recently the great shortage was in coal; for lack of fuel the smelters and factories failed to produce the very metals and equipment now needed to operate the mines. Nation-wide shortages have created a monstrous inflation of prices throughout all the economy, currently amounting to 200 times the prewar figures. For example, the price of copper ranged from 500 to 900 yen per metric ton for many years until 1937, but in mid-1948 producers were

Jan 1, 1949

By John A. Mathews

D R. CHARLES W. ELIOT, the great educator and philosopher-he of the five-foot book shelf-recently gave expression to a thought I had long been cherishing as a private opinion, when he said: "It is obvious that standardization has become a dangerous adversary of progress in both education and industry." This idea must have been more widespread than either of us knew, for some five years ago a writer of verse for one of the comic papers dealt with it at great length. I will quote only a few of his stanzas to illustrate his understanding of "A Standardized Existence" : A visitor at large, I stand Beneath a standard sky- Where everything is standardized To please the standard eye. Each tree is of a standard height, Each building is the same; Each man is uniform in height, And has a standard name. Above there is a standard star Beside a standard cloud, And a standard weather here prevails To please a standard crowd. With standard joy, and standard gain, The standard people live; And if there is one bit of pain T?is such as standards give.

Jan 1, 1926

By Merlin H. Aylesworth

THE subject assigned to me is peculiarly appropriate to the anniversary of the birth of Abraham Lincoln. If we applied to our present problems the ideals and methods of the Great Emancipator, the future of American institutions would be so definitely assured that there would be little need to discuss the matter. The only inquiries would relate to the pace of progress, not to the possibility of progress. As a nation we have grown more and more to revere the memory of Lincoln, to honor his character, to extol his teachings and to eulogize his concepts of democracy. We rec-

Jan 1, 1940

By Ernest R. Lilley

THOSE acquainted with the fundamental differences between the, educational .systems of Great Britain and. the United States would hardly expect .the training of men for the petroleum industry to proceed along the same lines- in the two countries. The youth entering an English university is, except in the case of-the student from some of the British colonies or from foreign countries, almost invariably a product of the English "public school." This is in no sense comparable .with the American public school. It is a private institution, frequently of considerable age and heavily endowed. In many aspects it seems to be comparable with the American preparatory school. Yet to some extent its activities remind one of the first years of the undergraduate: course in the American college. Certainly it takes to-itself many of the social, functions of the American college.

Jan 1, 1931

By A. O. HAYES

SYSTEMATIC methods of ore-finding are looked to the more as increasing production requires greater supplies of raw materials. Unrelenting search for new sources of supply is necessary, and all the skill of science must be displayed both in methods of discovering and recovering the minerals necessary to the demands of present-day life. To this end most national governments have some sort of a geo- logical survey and there is a growing understanding of the desirability for cooperation between federal and state or provincial organizations and also financial assistance, from state and private universities, mining companies, railroads and manufacturers. Such surveys are now being directed by well trained geologists selected from federal, state and university departments. Large-scale maps are being prepared and better geo- logical interpretation made, more thorough chemical and physical examinations are being made and original search is fostered, with the result that successful prospecting is better directed, new mining regions are more likely to be discovered, and the life of. old camps lengthened.

Jan 1, 1931

By D. K. Deardorff, Haruo Kato

D. K. Deardorff and Haruo Kato (U. S. Bureau of Mines)—We wish to refute the 1875" 20°C value that Giessen, et al., report as the transformation temperature of hafnium. Although these authors state that their work along this line will be reported later, we can't leave their value undiscussed, for we believe it to be 125°C too high. Our value of 1750° 20°C, which the authors mention, has been substantiated in our laboratories by the use of three other methods. The first method of substantiation was by heating and cooling curves using a hafnium/tungsten thermocouple, the couple having first been calibrated against a t/Pt-10 pct Rh couple. The second method was by quenching and metallography of dilute Hf-Ta alloys. The third cussion, it may be pointed out that the observations of Rogers referred to large unidirectional strains where the internal cracks or voids appeared only after a strain of 32 pct or more. On the contrary the internal fissures observed, as a result of fatigue cycling, occurred for a total extension of some 5 pct and furthermore followed the directions of the slip zones. Finally, it is not our contention, as implied in Dr. Alden's last paragraph, that the tensile stress is an important factor in crack propagation. Indeed, in connection with the reference to the companion report, special note is made of the fact that "Deformation was apparently concentrated in grains which have a slip plane nearly perpendicular to the specimen axis and thus near the plane of maximum applied shear." This dependence of the growth of fissures on the orientation of the slip planes with respect to the direction of maximum applied shear is clearly shown in work on the torsional cycling of single crystals which has been submitted for publication. method was by heating and cooling curves with W/W-26 pct Re thermocouple. Counting the original resistometric method, four different methods have yielded 1750" 20°C as the transformation temperature of hafnium. All our work on determination of the hafnium transformation temperature has shown that the specimen under test must be quickly heated to and through the transformation temperature if the lowest possible transformation value is to be determined; otherwise a higher value not representative of pure hafnium will result. Speed was emphasized in all methods. In our resistometric work the corresponding voltage, amperage, and temperature readings were taken quickly and the transformation temperature was usually reached within 5 min total heating time. In the thermal analysis work involving Hf/W or W/W-26 pct Re thermocouples the transformation temperature was attained within three minutes total heating time, this time being less because the two variables were

Jan 1, 1963