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MINING ASSOCIATION, UNIVERSITY OF CALIFORNIA At a meeting of the Mining Association of the University of California, held Feb. 12, officers for the present semester were elected as follows: President, Richard C. Kerr, '19; vice-president, Glen T. O'Brien, '20; secretary, Kenneth V. King, '19; treasurer, Sam Grinsfelder, '20. KENNETH V. KING, Secretary.

Jan 4, 1919

By W. B. Gogarty

The reported decreases in water mobility do not seem unusual in view of non-Newtonian fluid properties. Shear stress vs shear rate diagrams have been reported for other solutions of water-soluble polymers. Some of these polymers are similar to the type mentioned by the author. Generally, the shear stress-shear rate is a non-linear function for these solutions. Data for plotting apparent viscosity vs shear rate can be obtained from this function. Apparent viscosity is defined as the ratio of shear stress to shear rate at a given shear rate. When plotted, the apparent viscosity decreases with increasing shear rate. This behavior is typical of a pseudoplastic fluid. For some water-soluble polymer solutions, the apparent viscosity decreases more than 50 times while the shear rate increases 1,000 times. Thus, viscosity of a pseudoplastic fluid only has meaning at a specified shear rate. Results of Fig. 1 could be explained in these terms. Viscosities measured in the Ostwald viscometer represent values at a given shear rate. Some average shear rate is affecting the polymer solutions while flowing through the core. This average value fixes the apparent viscosity as long as the flow rate remains constant. Viscosities measured by the two methods will be equal if shear rates are the same. The results indicate that shear rate in the core is lower (higher apparent viscosity) than in the viscometer. In the paper by Johnson, Bossler and Naumann, the relative permeability is independent of viscosity ratio. Thus, the relative permeability with respect to water flow at residual oil should be independent of the flowing phase viscosity. Polymer solutions will appear as Newtonian fluids The discussion emphasizes the nature of the "resistance factor effect" as discussed in the paper. Repeated anomalies arising in hundreds of experiments led us to the conclusion that non-Newtonian flow is not the only factor. Several of the key anomalies are as follows: 1. Measured viscosities over a range of shear rates from <1 sec-&apos; to 1,000 sec-&apos; do not account for but a minor fraction of the R observed in cores when compared in similar shear-rate ranges. 2. The slope of R vs flow rates in cores is always different from that expected from viscometer shear-rate measurements as shown in Fig. 2. in a core, the level of viscosity being fixed at a given flow rate. With these conditions, the definition of resistance factor R by Eq. 2 is simplified to Since , is constant with rate, R becomes a measure of the apparent viscosity in a core at a given flow rate. Variation in flow rate could easily account for the changes of R shown in Fig. 5. Also, this points to the fallacy of assuming R to be a unique parameter. The constant resistance factors at different flooding velocities appear to be in disagreement with the above discussion. The author furnishes Fig. 2 to support his arguments. As shown, the resistance factors remained substantially constant in the two cores over a considerable range of flooding velocities. However, in the 73-md core, the factor increases at lower rates. This behavior agrees with known characteristics of some pseudoplastic material. These materials act both as Newtonian and as non-Newtonian fluids in different regions of shear rate. Some exhibit first Newtonian, then non-Newtonian, finally, Newtonian character. Others are first non-Newtonian and then Newtonian. This latter type would explain the results with the 73-md core. The Fann-instrument results are not significant since shear rates in the core may be much different than with the viscometer. The higher resistance factor at high rates in the 150-md core is more difficult to explain. The greater resistance at increased flow rates could be attributed to what might be termed temporary bridging. As envisioned, changes in polymer configuration occur at the higher energy associated with the increased flow rate. These changes could cause less effective passage of polymer through the core. Correspondingly, increases in pressure drop will occur. These will be interpreted as higher resistance factors. 3. Most polymer solutions are non-Newtonian and many are more shear-rate sensitive than the polymers in question, yet only a very few polymers demonstrate useful R values. Gogarty&apos;s assumption that viscosities in cores and vis-cometers will be the same if measured at the same shear rate is only valid if non-Newtonian rheology is the only parameter. The experimental evidence does not validate this assumption. The anomalies observed in the equilibrium displacement experiment shown in Fig. 5 are not explained on the basis of varying flow rates since the rates were held constant. M

Jan 1, 1965

By AIME AIME

MIING Engineer. Metallurgist, Economist-in any of those three capacities Paul Tyler should be able to make a living. Further- more, he has proved his ability as an operating man teacher, researcher. and prolific writer. For the last three years he has been chief engineer of the non-metal Economics Division of the. U. S. Bureau of Mines.

Jan 1, 1941

The information in Tables 1 and 2, on the operations in the Dutch East Indies and North Borneo, has been kindly furnished to the Institute through the courtesy of Mr. J. August Kessler by Mr. B. H. van der Linden. It affords a very good picture of the situation in that region for the year 1933.

Jan 1, 1934

E. E. THUM, * Salt Lake City, Utah (Written discussion ?).-Dr. Fulton&apos;s paper sheds a great deal of light upon questions which have perplexed many who have studied the metallurgy of zinc, and have fruitlessly brought forth several hypotheses and reams of discussion. It would be a bright day if others would follow Dr. Fulton&apos;s example, for, as a

Jan 11, 1918

By Christian F. Baiz

INTRODUCTION Industrial minerals can have similar financing requirements to those needs of metaliferrous and coal mining projects. One of the outstanding differences is the understanding of the many different markets that these industrial minerals represent. There are in excess of 30 principal industrial minerals ranging in terms of annual production from the largest quantity such as sand and gravel, to possibly the smallest quantity of production of a legitimate industrial mineral which may be defined as industrial and rough gem diamond. (See Tables 1 and 2) Project finance techniques, analytical methods, and information requirements are covered elsewhere in this Chapter and Chapter 10. Some comments on equity finance aspects follow. EQUITY AMOUNT The amount of equity in a financing transaction provides a cushion to the lender in case the project runs into trouble. Generally speaking, the greater the amount of risk in a project, the more equity a lender will require. The amount of cash equity in a project financing transaction is between 25 and 40 percent. The amount of leverage (debt/equity) is negotiable based on such factors as the strength and extent of the sponsor&apos;s undertakings, of the project&apos;s economics, and the term of a strong sales contract. Naturally, a borrower seeks to obtain d loan with as little equity required as can be negotiated. Zero percent equity is usually associated with a take-or-pay contract (a hell-or-high- water unconditional commitment under which the purchaser must pay for the commodity as though it were shipped regardless of whether it is actually mined or shipped) with a financially strong corporate entity i.e., the parent company or an end user. As a take-or-pay contract is tantamount to a guarantee of payment, the banker views the credit basis of the loan as being other than the borrower&apos;s mining operation and therefore will analyze the creditworthiness of the institution purchasing the commodity on the basis of its corporate balance sheet. Do not confuse a take-or-pay contract with a take-if- tendered or take-and-pay contract. Another means in the United States of obtaining zero percent equity is the carved out production payment financing, typical of coal mine financing. This involves the sale, or conveyance, by the owner of the mineral property of a production payment to a nominally capitalized company. The nominally capitalized company is formed solely to buy the production payment and usually borrows 100 percent of the purchase price from a lender. Equity amounts of 10 to 20 percent generally are found in transactions which employ techniques such as an advance sale or a subordinated lease/loan. These agreements are viewed as quasi equity by most banks for several reasons. First, the proceeds represent a cash infusion early in the project&apos;s life - usually prior to the bank lending any funds. Thus, the repayment schedule is "behind" that of the bank debt. In the case of an advance sale, repayment is in the form of a long-term supply contract with favorable terms, usually priced close to the mining operation&apos;s costs. There is also usually a requirement that all costs of the project be paid for by the loan or equity, often making the sponsors financially responsible for any cost overruns. Cost overruns are a major risk in any project, large or small, and are often due to unforeseen factors such as wildcat strikes, a piece of faulty equipment, or any event which delays completion, e.g., remote location, weather, etc.. . The question of how overruns are covered can be negotiated. For example, in addition to the original debt/equity ratio of the project, there can also be a cost overrun ratio that will

Jan 1, 1985

By J. H. Jackson, P. D. Frost, C. H. Lorig, L. W. Eastwood, A. C. Loonam

R. S. BUSK*—I wish first to congratulate the authors of this paper both for the work done and the presentation of that work. We have also been working on this type of alloy development, but any technical contribution I might have is better reserved for a separate paper which is planned in the near future. However, I would like to insert a word of caution. The alloys described in this paper are still very much in the laboratory stage. There still remains the quite vexing problem of property stability at slightly elevated temperatures which must be solved before the properties quoted can be effectively utilized. These alloys are extremely interesting and I am confident that the problems can be solved. However, the present existence of those problems must not be overlooked. I have one question with regard to the work-hardening test. If the work harden-ability of magnesium is compared to aluminum using a more standard test such as the Meyer Analysis the magnesium is found to work harden the more rapidly. Is the test developed for this work truly a work-hardening test or a measure of something else ? J. H. JACKSON (authors&apos; reply)—I am sure we appreciate the comments of Mr. Busk and we are pleased that the Dow Chemical Co. has also undertaken work in this field. It is a big field. We, of course, are continuing our research for the Navy Bureau of Aeronautics, since, as clearly shown in the paper, the alloys are not completely developed. With regard to Mr. Busk&apos;s comments on the relative work-hardenability of aluminum and magnesium, the comparison we cited in the paper was intended merely to show that the results obtained by our method of testing were independent of the yield strength of the materials. We believe that this test method afforded a rough indication of the work-hardenability of the magnesium-lithium base alloys. It is not known whether this method affords greater or less accuracy than the Meyer Process, which is based upon a hardness-test impression. It is quite possible, since work-hardenability is a function of metal purity, that our results, obtained for commercial aluminum and magnesium, would be different if high-purity metals had been used. A. C. LOONAM—Lithium has some very interesting effects on magnesium. The paper showed that even small percentages increased ductility. These small amounts changed the axial ratio of the hexagonal magnesium from 1.624 in the pure metal to 1.606 in the saturated alpha solution, a value close to that of titanium, which has a ratio of 1.601. You will recall an article in the January, 1949, issue of the Journal of Metals where it was stated that titanium can be cold-rolled over 90 pct without any significant edge cracking. At 4.9 or 5 pct lithium, a change begins in crystal structure—from a hexagonal close packed to body centered cubic. There are two phases over a short range of lithium content, but at 10 pct the structure becomes completely cubic. The melting points of alloys in this range of lithium content are relatively high. Alloys even up to the six ratio have melting points above 500°C; this represents a relatively small reduction in melting point from pure magnesium itself. The magnesium-lithium system has a number of very interesting characteristics. This is only a very small part of the story. J. H. JACKSON—I would like to remind you that Mr. Loonam is one of the authors of this paper, and the fact is that this work is based on many of his ideas. I am sure we appreciate his additional comments in this discussion. R. LEITER*—I am interested in Fig 19 in which Mr. Jackson compares

Jan 1, 1950

By Ronald J. McGregor, Anton R. Hendriksz

INTRODUCTION The NIMCIX contactor was developed in the late sixties at the National Institute for Metallurgy in South Africa, for the main purpose of extracting uraniuy from relatively low-grade uranium solutions. &apos; The concept was sufficiently developed by 1974 to permit the operation of a 1500 litre per minute column to treat unclarified urgnium-bearing solution under industrial conditions. The plant operated so successfully that several large-scale units have subsequent18 teen constructed and are operating efficiently. &apos; Total resin consumption figures as210w as 3 per cent per annum have been reported, and the extraction efficiencies of the installations have been exceptionally good. All the solutions treated have been acidic in nature and in every case have been of such a nature as to significantly depress the maximum uranium loading on the resin beads. The chemical constituents of the leach solution fed to the loading column determines the ease with which the soluble uranium can be absorbed by an ion exchange resin. The concentration of competing ions and various resin foulants define the nature of the continuous ion exchange equipment required for efficient extraction performance. The basic NIMCIX concept is retained in these various alternate designs, but batch or continuous elution methods with fully automated or manual control systems may be selected for the different process solution conditions. BRIEF DESCRIPTION OF THE NIMCIX CONTACTOR The NIMCIX ion exchange column is a multi-stage fluidized bed contactor which is designed to permit a counter-current flow of solution and resin in order to maximize extraction efficiency. The flow o resin is periodic, based on the Cloete and Streat 5 principle of reverse flow. The basic operating cycle can be divided into five periods, as illustrated in Figure 1. For the purposes of describing the cycle, the loading column is considered; how- ever, a similar sequence may be applied to the operation of a NIMCIX continuous elution column. S&apos;I&apos;EP 1: During the forward flow period, Solution flows up through the column and fluidizes the resin contained in each stage. The uranium depleted solution overflows the upper flared-section of the column as the tail solution. Step 2: The flow of solution to the column is temporarily stopped and the resin is allowed to Settle onto the plates in the column. STEP 3: During the reverse flow period, a fixed volume of solution is drained from the column to the transfer vessel. This flow causes resin transfer to occur from stage to stage and also out of the bottom stage. At the end of this period, which expires when the low level switch (LS) is actuated, some of the resin is left in the conical section of the column and the pipe interconnecting the column and the vessel. STEP 4: The cone flush period ensures that all the resin left in the cone of the column and the pipe is transferred to the transfer vessel before forward flow commences. STEP 5: The loaded resin in the transfer vessel, which has been isolated from the column, can either be hydraulically transferred to the top of the elution column or eluted in the vessel before being transferred to the top of the loading column. The major advantages associated with the NIMCIX concept are: (i) Simple method of operation (ii) Contactor can readily be scaled up to large diameters. (iii) Because the resin does not pass through pumps or airlifts, and valves cannot be closed on resin beads at any time, the resin losses are exceptionally low. (iv) Operating costs are low. (v) Relatively few valves in the system. (vi) Stable operation is achieved over a wide range of feed rates and concentrations.

Jan 1, 1980

By B. L. Averbach, M. Cohen, C. H. Shih

The isothermal formation of martensite is studied in Fe-Ni-Mn and Fe-Mn-C alloys under conditions where the athermal transformation is completely avoided, there being no martensite present at the beginning of the isothermal reaction. The initial rate of martensite formation is extremely low under these conditions, but it increases greatly as soon as some martensite is formed. It appears that true initial characteristics of the isothermal reaction can be studied only in samples wherein the formation of martensite on cooling is completely eliminated. THE phenomenon of isothermal martensite formation is well established1 -" but the observations have been made in the presence of varying quantities of athermal martensite. Complete avoidance of athermal martensite and the formation of martensite under pure isothermal conditions have been reported by Kurdjumov and Maksimova2 in an Fe-Ni-Mn alloy (23 pct Ni, 3.4 pct Mn, and the balance Fe) and have been confirmed by recent experiments of Cech and Hollomon in a similar alloy. In each case, the isothermal transformation rate was a maximum at the beginning of the transformation and decreased as the reaction proceeded. These initial transformation rates were used by Fisher7 for the confirmation of calculated nucleation rates based on classical nucleation theory extended to include the effect of elastic strain energy. Cech and Hollomon have admitted, however, that up to 3 pct martensite formed on cooling in their samples and thus was present at the initiation of their isothermal runs. In this paper, experiments on similar alloys are described, except that care was taken to remove the incidental martensite developed at the surface prior to the isothermal reaction. It is shown here that the reaction rate at the beginning of the strictly isothermal reaction is very low. As soon as some detectable amount of martensite is produced, the transformation rate increases rapidly but ultimately decreases as the reaction proceeds. When martensite is allowed to form isothermally in the presence of about 2 pct of prior martensite, the apparent initial reaction rate is a maximum and corresponds to the observations of Kurdjumov and Maksimova and Cech and Hollomon. It is evident that the cooperative nature of the martensitic reaction results in a significant stimulating or autocatalytic effect on the isothermal reaction rate. Experimental Procedure The chemical compositions of the alloys used in this investigation are listed in Table I. The Fe-Ni-Mn alloys A and B were melted in an induction furnace, cast into ingots 2 in. diam by 4 in. long, and forged into % in. diam rods. The manganese steel (alloy C) was melted in an arc furnace and cast into ceramic molds 1/4 in. diam by 5 in. long. The rods were sealed in evacuated Vycor tubes and homogenized at 1175" to 1200°C for 50 hr. The long homogenization resulted in some manganese loss from the surface, producing a thin layer of transformed material. This surface layer was removed by grinding and the specimens were then swaged to 0.050 in. diam wire. Measurements of electrical resistance were made with a Kelvin double bridge to follow the course of the martensitic transformation. A small permanent magnet was also useful in scanning an entire specimen for small localized quantities of martensite. This test is almost as sensitive as the electrical resistance method in detecting the presence of martensite (which is ferromagnetic in these alloys) and it was especially useful in deciding whether a specimen was completely free of martensite. The wire specimens (0.050 in. diam by 2.5 in. long) were sealed in evacuated tubes and austenitized for 5 min at 1150°C. The specimens were quenched into water and, unless otherwise stated, stress-relieved for 1 hr at 650 °C in order to induce greater uniformity in the subsequent martensitic transformation. As dem-

Jan 1, 1956

By S. F. Ravitz

IN his excellent book on the Principles of Flotation, Wark&apos; makes the following significant statement concerning the theory of flotation: Two questions of first-rate importance must be considered . . . First, it must be decided whether the sulfide minerals require a collector in order that they may float, or whether as has been claimed, they possess an inherent floatability and need no collector. Second, it must be decided whether the xanthate type of collector can react with or be adsorbed by the unchanged sulfide minerals themselves, or whether, as many claim, reaction with the collector is dependent upon initial oxidation of the mineral surface. In the theory of flotation there are no two questions of greater importance than these. Ravitz and Porter&apos; presented evidence that galena can be floated without a collector, and even without any reagent, provided oxidation products are thoroughly removed from its surface. They found also that thoroughly cleaned galena floated faster when xanthate was used than when a frother alone or no reagent was used, and that, without a collector, the recovery decreased gradually upon exposure of the mineral to air. Their work, however, has met with considerable criticism. I(127).3-6 This paper is presented to answer the objections that have been raised, and to present additional data that confirm their results. EXPERIMENTAL PROCEDURE The apparatus used to provide oxygen-free conditions for flotation has been described in detail by Ravitz and Porter. An atmosphere of purified nitrogen was maintained within the apparatus; all water and solutions used were freed of dissolved air, and could be transferred where desired by the use of nitrogen pressure; nitrogen was used as the gaseous medium for flotation. The flotation cell was essentially a glass cylinder 15 cm. long and 4.6 cm. in diameter. Near the bottom was sealed a fritted glass filter, which broke up the gas into small bubbles, and 6 cm. above this filter was a side arm through which the froth overflowed. The pulp was agitated by a glass impeller, which entered the cell through a mercury seal. For each test 17 grams of galena and 75 ml. of water were placed in the cell, after which the speed of the impeller and the rate of gas flow were adjusted. Water was added gradually during the test to keep the froth level at the proper height. The mineral was prepared and cleaned in the following manner. Exceptionally pure galena was crushed by hand on a clean bucking board, screened to - 150+ 200 mesh, and deslimed on a zoo-mesh sieve with a fine spray of water. It was then boiled on a hot plate for a number of hours with several changes of the desired cleaning solution, after which both the solution and the mineral were placed in the "mineral flask" of the apparatus. The cleaning solution was drained off, and the mineral was boiled with oxygen-free water

Jan 1, 1940

By David W. James

DURING a recent investigation of the transition from a planar to a nonplanar solid/liquid interface for the systems H20-NH4F and 0-AIR,&apos; an apparatus was developed which enabled the morphology of the ice-water interface to be examined during the transition. The slightly curved interface was viewed at a glancing angle with a Bausch and Lomb X30 stereomicro-scope. The interface was obliquely illuminated by a polarized light source. It was thus possible to differentiate between small projections or depressions at the interface, both by a shadowing effect and by the way in which they distorted the colored interference fringes across a particular crystal surface. Many attempts were made to photograph the various stages of interface breakdown. Unfortunately, the limited depth of focus of the microscope rendered the system unsuitable for photographic recording. Visual examination, however, was facilitated by continuous adjustment of the microscope focus control. The following observations of the interface transition were recorded for dilute solutions of ammonium fluoride in water. They are compared with iller&apos;s postulated morphologies shown in Fig. 1. i) The initial departure from planarity was characterized by the appearance of a large number of small depressions or "pores" in the interface. ii) The pores were arranged in wavy rows all lying roughly in the same direction within a particular grain. iii) The pores did not appear to form near to grain boundaries. iv) The pores appeared in certain grains before others. v) The transition from the pore structure to the elongated cell structure, Fig. l(d), was difficult to follow. It occurred quite rapidly and no truly irregular cell structure, Fig. l(c), was noticed. vi) The elongated cells gradually became more uniform in size and shape, with straight cell boundaries. They remained elongated, however, and no regular hexagonal cells were observed, cf. Fig. l(e). Several conclusions may be drawn from these observations. Firstly, the appearance of a poxed or, more accurately, a pore structure can be used as a criterion for the onset of constitutional supercooling. Care should, of course, be taken to distinguish between the true pore structure and artifacts caused by splashed-back liquid, particles of oxide, or inefficient decantation of liquid retained between cell boundaries, as described by Spittle et al? Secondly, and contrary to the suggestions of Tiller el l., it seems that interfacial perturbations are characterized not by curved projections but by small depressions or pores. A recent independent investigation by Biloni, Bolling, and cole5 reported in this issue indicates that the depressions might be explained in terms of dislocations intersecting the solid/liquid interface. It is possible that the dislocation concentration is reduced in the vicinity of grain boundaries. This would then explain the grain boundary depleted areas noted in (iii) above. This work was partially supported by the Air Force Office of Scientific Research, Contract No. AF 49-(638)-1029.

Jan 1, 1967

By AIME AIME

THE joint symposium on gases in metals on Tuesday: Feb. 16, between the Iron and Steel and the Institute of Metals divisions opened the technical sessions for both of these bodies. After a few words of introduction by P. D. Merica, R. S. Dean presented a paper by V. H: Gottshalk and himself on the solubility of gases in metals.

Jan 1, 1932

In the General Alphabetical and Analytical Index of A I M E Publications for the years 1926 through 1935, a complete list of the volumes covered is printed on page 5, but the dates of publication of the volumes are not given Therefore the following information regarding the volumes that were printed without numbers may be useful to users of the Index

Jan 1, 1937

Arrangements have been made for a cooperative investigation of the fatigue phenomena of metals by the University of Illinois, the Engineer-ing Foundation, and the National Research Council. The work will be done in the laboratories of the Engineering Experiment Station, the Committee on the Fatigue Phenomena of Metals of the National Re-search Council acting as an advisory committee.

Jan 12, 1919

By J. J. Bodmer

The four different modes, more or less practiced for subdividing slag (that is, producing slag sand), are the following: 1. Crushing the slag from the lump in Blake&apos;s crusher, by edge runners or other suitable means. 2. Blowing water, steam, cold or hot air, into the stream of viscous slag whilst it runs from the furnace. So treated, the slag takes

By J. J. Bodmer

THE four different modes, more or less practiced for subdividing slag (that is, producing slag sand), are the following : 1. Crushing the slag from the lump in Blake&apos;s crusher, by edge runners or other suitable means. 2. Blowing water, steam, cold or hot air, into the stream of viscous slag whilst it runs from the furnace. So treated, the slag takes

Jan 1, 1874

By Louis Moyd

The Concrete Research Division, U.S. Corps of Engineers, has developed a simple procedure for determining the coefficients of linear thermal expansion of rocks by means of resistance wire (SR-4) strain gauges. Gauges are cemented to the surfaces of specimens, which are then brought alternately to temperatures of 35°F and 135°F. Results are accurate to the seventh decimal place.

Jan 6, 1950

A small group of members of the Institute headed by W. H. Shockley, has insistently demanded that the Institute submit to the members for letter ballot the question of our using in our publications and corre-spondence certain so-called "simplified spellings." The principal argu-ment in favor of this proposal is written by Mr. Shockley and will be submitted in full to the membership for ballot. It rests chiefly on the desirability of saving the time of school children in the learning of the spelling of the English language. A sample of correspondence had with one of the gentlemen on this subject is given herewith in order that members may see what the correspondence and publications of the Institute would look like if we adopted the proposals. This sample was chosen at random: "Onse I condemd the report ov a president of the Institute. He did not pruve his case even on paper-"a hot air profet," I sed. Time has pruved he was." "I rote yu about the muvement to better the spelling in the Institute Bulletin, etc., neglecting to say some things that I mite hav said and things hav happened since which no member ov a democratically governed society shoud stand without protest."

Jan 12, 1919

W. B. PRICE,* Waterbury, Conn. (written discussion??.-It has been our experience, especially in cupro-nickel, that manganese has been very beneficial, not only, as stated by Mr. Braid, in removing sulfur, but also for its property of reducing oxides, thus making the metal more fluid, and enabling it to be poured at a lower temperature; this, in turn, prevents softening of the graphite pots and the absorption of carbon. It also acts very effectively in keeping the carbon in solution in the cupro-nickel, in the combined form. However, in the case of cupro-nickel, to obtain all these benefits it has been found necessary to keep the manganese content as near 0.25 per cent. as possible. Manganese also is very effective in diminishing the amount of blisters in cupro-nickel. So far as I am aware, both from personal experience and from the experience of others who have been engaged in the manufacture of nickel-silver and cupro-nickel, manganese used either in the form of pure metal or as manganese-copper alloy (30 Mn, 70 Cu) gives better results than any other flux. While this may seem a strong statement, manganese is the natural flux for nickel-silver and cupro-nickel.

Jan 12, 1918

Between two and three years ago, in response to an unmistakable and insistent demand, the four Founder Societies appointed Committees on "Aims and Organization," or on "Development," charged with reporting on the internal organization and the external (non-professional) ac-tivities of the engineers societies and to advise as to coöperations and coordination. Each of these committees formulated a report, recognizing that effi-ciency in external activities could only be attained by intimate coopera-tion between the four Societies. As a consequence, each of the Founder Societies was requested to appoint members of a Joint Conference Committee, charged with discussing the situation and evolving if possible a plan of cooperation in external activities which would coordinate not only the efforts of the four Founder Societies but also other national technical and scientific societies, as well as local engineering and profes-sional associations, groups or clubs. The Joint Conference Committee entered on its task with enthusiasm, and after great labor evolved the outline and many of the details of plan for engineering cooperation in public and inter-society activities. This report has now been submitted to the Boards of the Four Founder Societies, and has been ordered printed by our Board for the information of our members.

Jan 12, 1919