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Jan 1, 1907

By O. Schaaber

THE existence of isothermal martensite without the presence of the athermal form thus far has been established only in a 6 pct Mn, 0.6 pct C steel' and a 23 pct Ni, 3.5 pct Mn-Fe alloy.' " Theoretical calculations, moreover, predict this phenomenon to be observable only within narrow composition limits.' In all other steels, it is generally considered that martensite inevitably forms upon cooling below the M, temperature. Even the possibility of isothermal martensite transformation has been questioned for the common steels, although Averbach and Cohen" showed that martensite formation does not stop when the cooling is arrested and that as much as 5 pct retained austenite may transform isothermally to martensite at room temperature. This note presents some observations made on a number of low alloy steels by dilatometric and inductive measurement of isothermal austenite transformation at various temperatures close to the Ms. In the dilatometer studies reported previously, austenitized specimens were immersed in a salt bath maintained at proper temperature and immediately inserted into the dilatometera8' already at thermal equilibrium with the bath. The dilation was read on a dial gage divided into 0.001 mm intervals. Induction measurements were made with a separate excitation source and a test coil, sealed together in a salt-tight case. The increase in the induced voltage caused by the transformation products was recorded at a paper speed of 4 mm per sec. The steels studied are listed in Table I. Specimens prepared from steels 1 and 2 were in the form of hollow cylinders 60 mm long, 10 mm ID, 14 to 16 mm OD, while specimens of steels 3 and 4 were in the form of notched-bar impact test specimens, DVM type. Specimens of steel 5 were in the form of strip, 7x0.3 mm. In the bainitic range, curves representing the amount of transformation vs log time have a single step appearance, as is shown by the curve of isothermal transformation at 320°C in Fig. 1.Y ransformation proceeds in accordance with the Austin-Rickett equationo P -----------= k t" 100-P where P is the percentage of transformed austenite, t is time, and k and n are constants. Near the M, temperature, however, complex curves having two steps are observed. As shown in a previous papera for steel 3 isothermally transformed at 245"C, such complex curves can be separated into two separate transformations or reactions each following the Austin-Rickett equation. The values of n in the equation for a number of such two-step transformations are listed in Table 11 for steel 1. At transformation temperatures of 250" and 235"C, evidence of a second transformation is very

Jan 1, 1956

By Walter Miller

BY the beginning of 1945 the output of petroleum products for war had reached a volume and a rate of growth which practically assured all requirements so long as war continued. The programs for making gasoline, lubricating oils of required quality, toluene for T.N.T., and chemicals for manufacture of synthetic rubber, as well as numerous other lesser petroleum products, were all well in hand, and unless catastrophic developments occurred there was no doubt of the ability of the industry to meet all demands. The end of the fighting found the refining industry working at top capacity on war commodities, but also in position to convert quickly into peacetime civilian production. 100-octane Aviation Gasoline Production of the vital 100-octane aviation gasoline, starting with approximately 44,000- bbl. daily capacity at our entry into the war, reached a top of 525,000 bbl. a day in the United States by the end of hostilities. With 75,- bbl. from other Allied sources, the grand total was 600,000 bbl., or 25,000,000 gal. each 24 hr. available to the armed forces had fighting continued. At times it was a close race between requirements and production, but never were any important military operations involving the use of high-octane aviation gasoline held up or delayed for lack of sufficient output of such material. The undivided effort of the entire refining industry in full cooperation with the Government made this record possible. Little diminution in output followed the German surrender on May 7. Plans called for a correspondingly greater activity for the Japanese war and possibly for well into 1946. But when the Japanese sued for peace on Aug. 10 most contracts were quickly canceled. Substantial stocks, reputed to be somewhere between 20,000,000 to 30,000,000 bbl., built up largely between V-E and V-J day pending organization of the larger Japanese war program envisaged after Germany gave up, were in the Government's hands in this country, in addition to working stocks in the war areas. Toluene and Lubricating Oil Requirements for toluene for T.N.T. increased rapidly as bombing speeded UP with increasing control of the air by the Allies in Europe and Asia. Production in excess of T.N.T. requirements which had been going into 1000-Octane aviation fuel blending during 1943 and 1944 was again drawn into explosive manufacture early in 1945. In anticipation of the war continuing into 1946, two new plants were ordered constructed, the decision being announced in April, plans calling for one of them to get into production about the end of 1945, the other in the first quarter of 1946. Both of these projects were later canceled as victory made it evident that the additional supplies would not be needed. Production was

Jan 1, 1946

By Walter Miller

BY the beginning of 1945 the output of petroleum products for war had reached a volume and a rate of growth which practically assured all requirements so long as war continued. The programs for making gasoline, lubricating oils of required quality, toluene for T.N.T., and chemicals for manufacture of synthetic rubber, as well as numerous other lesser petroleum products, were all well in hand, and unless catastrophic developments occurred there was no doubt of the ability of the industry to meet all demands. The end of the fighting found the refining industry working at top capacity on war commodities, but also in position to convert quickly into peacetime civilian production. 100-octane Aviation Gasoline Production of the vital 100-octane aviation gasoline, starting with approximately 44,000- bbl. daily capacity at our entry into the war, reached a top of 525,000 bbl. a day in the United States by the end of hostilities. With 75,- bbl. from other Allied sources, the grand total was 600,000 bbl., or 25,000,000 gal. each 24 hr. available to the armed forces had fighting continued. At times it was a close race between requirements and production, but never were any important military operations involving the use of high-octane aviation gasoline held up or delayed for lack of sufficient output of such material. The undivided effort of the entire refining industry in full cooperation with the Government made this record possible. Little diminution in output followed the German surrender on May 7. Plans called for a correspondingly greater activity for the Japanese war and possibly for well into 1946. But when the Japanese sued for peace on Aug. 10 most contracts were quickly canceled. Substantial stocks, reputed to be somewhere between 20,000,000 to 30,000,000 bbl., built up largely between V-E and V-J day pending organization of the larger Japanese war program envisaged after Germany gave up, were in the Government's hands in this country, in addition to working stocks in the war areas. Toluene and Lubricating Oil Requirements for toluene for T.N.T. increased rapidly as bombing speeded UP with increasing control of the air by the Allies in Europe and Asia. Production in excess of T.N.T. requirements which had been going into 1000-Octane aviation fuel blending during 1943 and 1944 was again drawn into explosive manufacture early in 1945. In anticipation of the war continuing into 1946, two new plants were ordered constructed, the decision being announced in April, plans calling for one of them to get into production about the end of 1945, the other in the first quarter of 1946. Both of these projects were later canceled as victory made it evident that the additional supplies would not be needed. Production was

Jan 1, 1946

By Max Ball

AN intelligent discussion of the oil situation and its needs, whether from the standpoint of the prospector, the operator, the engineer, or the public administrative officer, must be founded upon a knowledge of the law under which oil lands are obtained. A consideration of new legislation must be prefaced by an understanding of the present law and its results. This paper undertakes to present no new remedy for the ills of the present situation, no new solution of the problems the oil business is facing. It attempts merely to summarize the present law, its provisions, its origin, its development, and its effects. The discussion does not pretend to be exhaustive from a legal standpoint. It aims to avoid legal intricacies Which tend to confuse rather than clarify. It seeks but to present the essentials of the existing situation. The title to government lands known to contain valuable deposits of petroleum may be acquired only under the terms of the placer law as embodied in Section 2329 et seq. of the Revised Statutes. As a preliminary to considering the desirability of this situation it is profitable to examine into its origin. ORIGIN OF THE LAW Congress has left no room for doubt as to the legal applicability of the placer law to oil lands. The Act of Feb. 11, 1897 (29 Stat., 526), provides: "that any person authorized to enter lands under the mining laws of the United States may enter and obtain patent to land containing petroleum or other mineral oils, and chiefly valuable therefor, under the provisions of the laws relating to placer mineral claims."

Jan 6, 1914

By R. P. Heuer

In recent years an increasing amount of research work has been done on refractory materials for use in copper-smelting furnaces. A few of the larger refractories manufacturers have erected special research laboratories which are fully equipped to study the refractory problems of the smelter. A typical laboratory of this type was described in the January, 1929, issue of Mining and Metallurgy, in an article entitled "Methods of Research Newly Applied to Refractories," by W. F. Boericke. This particular laboratory is equipped for the manufacture of full-size refractory brick. It aims to study on a fairly large scale the behavior of various refractory raw materials and the effect of improved methods of manufacture. The refractories manufacturer has at his disposal the naturally occurring refractory oxides in various degrees of purity, mixed or combined with other oxides. In order to supply the copper smelter with a refractory brick that will permit the most economical operation of the smelting furnaces, it is necessary to have the optimum combination of a number of both physical and chemical properties in the brick. Unfortunately, nature has not provided any raw materials in which the perfect combination of these properties exists. It is, therefore, a problem for man's ingenuity to seek out the most desirable raw materials and develop methods of manufacture that give, in the resultant product, the necessary combination of properties in as full a measure as is possible. In the laboratory it is possible to carry out fairly broad experiments with this objective. It is first necessary to obtain and process the raw materials, then to manufacture them into brick and finally, to test these bricks under conditions designed to interpret or simulate in the laboratory the actual conditions in the smelting furnace. It is necessary for the research engineers to determine certain fundamental properties in the brick which may be subjected to laboratory measurements and to interpret these measurements in terms of brick performance in smelting-plant practice. Such procedure is not what might be called an exact, scientific one but it has been found that great progress can be made when these principles are applied. For example, the resistance of refractory brick to spalling and thermal change can be related to the thermal expansion of the refractory, its thermal conductivity and heat capacity and its

Jan 1, 1934

US 4,181,588 - Direct extraction of lead from lead sulflde ore. Ore is leached with a solution of ferric chloride and sodium chloride. The leach liquor is filtered to remove sulfur and gangue, then cooled in a crystallizer to precipitate lead chloride The slurry from the crystallizer is subjected to electrolysis to deposit lead chloride on the cathode plate. Solution from the electrolysis cell is used in the leaching step. M.M. Wong and F.P. Haver, assigned to US Secretary of the Interior Jan 1, 1980. 6 pp. (204-115). Filed: 1-4-79 (1,026).

Jan 1, 1982

By T. Kilner, A. Plumtree

DURING an investigation of electro-deposited silver structures, samples were prepared for metallographic examination by cold mounting in plastic, grinding on successive grades of emery paper down to 3/0, and chemically polishing by swabbing using the chromic acid solution described by Gilpin and Worzala.1 Attempts to etch these samples using the standard solutions described for silver (e.g., 5 pet KCN-5 pet Na2S2O8, H2O2-NH4OH, and various potassium dichro-mate solutions) all failed to give good results due to staining of the samples and to rapid etching. The staining was caused by the chromic acid polishing solution being trapped in small fissures between the sample and the mounting plastic, and also in small fissures in the sample itself. To overcome these difficulties, an etchant was developed which prevented staining at the same time as it slowly etched the sample. This resulted in a very clean, crisply etched surface as shown in Figs. 1 and 2. This etch consisted of 10 ml of orthophosphoric acid, 10 ml of distilled water, and 2 drops of the polishing solution noted above,' which is made by mixing 100 ml of saturated CrO3 solution, 45 ml of 10 pet HC1 solution, and 800 ml of distilled water. The etching procedure involved taking the final polished sample, either immersing or swabbing in the etchant for a period of 1 to 2 min, rinsing as quickly as possible in distilled water, alcohol, and ethyl ether in that order, and then immediately drying. This etch is easily controlled due to its slow rate of etching, and produces samples with clean, sharp surfaces. Pits due to overetching produced varying contrast effects when viewed under polarized light, and are therefore obviously useful for revealing many structural details within the sample. Another effect of overetching was to produce a height varia-

Jan 1, 1968

By M. A. Bryant, J. C. Goodwin, T. B. Faddies, L. D. Kornze

The Mercur Gold Mine is located 56 km (35 air miles) southwest of Salt Lake City in north central Utah; In July 1981 Getty Mining Company made the decision to put Mercur into production. The first gold bar was poured in April 1983. This paper provides details on: 1) the history of the camp, 2) past production, 3) geology of the deposit, 4) the exploration and development program, 5) ore reserve estimates, 6) detailed geologic pit mapping, 7) production blasthole sampling techniques and 8) the use of geostatistics (kriging) in handling assays and gold extractions to produce the required mill feed.

Jan 1, 1985

By Charles M. Brinckerhoff

When I first went to Arizona in 1925, mining was primarily an underground job. Ajo, Sacramento Hill in Bisbee and Jerome were the only open pit operations in the state. Thousands of men, however, were employed in underground mining at Morenci, Miami, Inspiration, Globe, Ray, Bisbee, and Superior. The grade of ore in the larger operations was about 1-1/2% copper while a few of the smaller ones mined ore better than 2% Cu. In Utah, the Bingham pit was doing well and growing; in Montana, the vein mines of Butte still yielded ore running 6% Cu.

Jan 3, 1972

By H. J. Maguire

Those familiar with mill-practice understand the work required of an average bucket-elevator, but I wish to call special attention to the wear on the buckets. I have been studying in what manner the life and service of the bucket might be improved, and I feel that an adjustable lip, attachable to each bucket without the aid of rivets, will be of material advantage. For illustration, consider the feed-elevator of a typical mill in the Cæur d'Alene district. The ore is carried by water in a launder from the feed-rolls and dumped in the " boot" of the elevator, directly in front of the ascending bucket. Middlings from the return-rolls are similarly handled. Under this condition the bucket not only carries the ore, but also picks it up, and this latter requirement determines the life and service of the bucket. It might be said that it would be better practice to convey the feed to the elevator and dump it directly into the bucket, but at one mill at which this plan mas tried the results were disappointing and the rubber belt was badly worn. The wear of the bucket is confined to the lip and the corners which have to pick up the material. When the lip on a corner of a '7- by 12-in. malleable cast-iron bucket is worn down about 3 in., the bucket is of no further value as a carrier and has to be replaced. The worn bucket, containing about three-quarters by weight of the metal of the original bucket, has a scrap value of about 10 per cent. of that of a new bucket. To the cost of the bucket, however, should be added the time-

Jan 1, 1913

The 38 companies listed below are those substantially engaged in the mining of metals, non- metals, or coal which appeared among the country's top 500 (on the basis of sales volume) listed in the July 1966 issue of Fortune. General Motors, with $20.7 billion in sales, heads the entire list, and a prominent member of the mining industry, Island Creek Coal, occupies the 500th spot with sales of $109.6 million. The lists of "industry medians" following mining's "Top 38" reveal how well the mining industry fared in 1965 in various salient categories of business performance.

Jan 9, 1966

By W. C. Schroeder

During the post-war period, and particularly during the past few years, coal production has been maintained at a reasonably constant level. This is in contrast to the greatly expanded demand for oil and natural gas. Certain markets for coal, such as the railroad and for home heating, have tended to decrease, but this decline has been offset by an increase in demand for other uses, particularly for electric power. Since the United States has very large reserves of coal and relatively limited reserves of natural gas and oil, from the conservation viewpoint, it would be better if the increased demand were to fall more heavily on coal. Where coal has lost certain markets, the decision has not always been made on the basis of price, and, in fact, in many instances, the markets have been lost where coal could show a price advantage. There are various reasons for this situation but it can be attributed in the main to the preference of certain consumers for the convenience offered by liquid and gaseous fuels. In the production of chemicals such as benzene, phenol, or ammonia, coal still plays an important role. As co-products from coke-oven operations, a wide variety of aromatic chemicals are available. In recent years, however, the production has not been sufficient to supply the demand, and it is not profitable to build coke ovens to make chemicals unless there is a market for the coke as well. As a result, the petroleum industry is beginning to take a stronger part in the production of aromatic chemicals. Natural gas has almost displaced the coke-oven water-gas machine for the production of hydrogen for the synthesis of ammonia, as well as for the synthesis of methyl alcohol and other oxygenated compounds. This information is not new and is given here only as a basis for the discussion of the broad significance of the development of the gasification process. It is clear that if coal is to regain some of its old fuel markets, as well as to maintain a position in the field of chemical synthesis, processes must be available for converting coal to the type of fuel the customer wants, and for a cheap method of furnishing gaseous raw material to the chemical industry. The operation of coke ovens and water-gas machines is not the answer to this problem for at least two important reasons: (1) the limited supply and relatively high price of good coking coals, and (2) the relatively high costs of the combined operations of coking and manufacture of water gas.

Jan 1, 1953

By John T. Galey

The restrictions placed on drilling by the Federal Government, which caused a severe curtailment in activity at the beginning of the year, were relaxed somewhat so as to permit the drilling of one shallow† gas well per 40 acres. New wells numbering 574† were drilled for a combined depth of nearly 1,500,000 It., and of this number 131 were dry holes with a footage of slightly over 375,000. Inside locations account for the majority of these totals and the increasing demand for natural gas would normally have increased the number considerably, but many of the independent operators chose to ask for fewer exceptions to Order M-68 of the Office of Production Management, and consequently to curtail the number of wells drilled. Initial open flow of natural gas developed from all operations§ is over 230 million cu. ft. Nearly 191 million cu. ft. of this volume resulted from the 410 new gas wells drilled to horizons above the Lower Devonian, and the footage drilled in these wells accounts for approximately 93 per cent of the total. Shallow Development Oil.—Thirty oil, wells, with a total initial production of slightly over 152 bbl. and a footage of 50.000, were drilled during the § Including deepening wells previously drilled.

Jan 1, 1943

By John T. Galey

The restrictions placed on drilling by the Federal Government, which caused a severe curtailment in activity at the beginning of the year, were relaxed somewhat so as to permit the drilling of one shallow† gas well per 40 acres. New wells numbering 574† were drilled for a combined depth of nearly 1,500,000 It., and of this number 131 were dry holes with a footage of slightly over 375,000. Inside locations account for the majority of these totals and the increasing demand for natural gas would normally have increased the number considerably, but many of the independent operators chose to ask for fewer exceptions to Order M-68 of the Office of Production Management, and consequently to curtail the number of wells drilled. Initial open flow of natural gas developed from all operations§ is over 230 million cu. ft. Nearly 191 million cu. ft. of this volume resulted from the 410 new gas wells drilled to horizons above the Lower Devonian, and the footage drilled in these wells accounts for approximately 93 per cent of the total. Shallow Development Oil.—Thirty oil, wells, with a total initial production of slightly over 152 bbl. and a footage of 50.000, were drilled during the § Including deepening wells previously drilled.

Jan 1, 1943

By J. C. Bierlein, R. A. Dodd

Endurance strengths at 10' cycles, fatigue-hardening rates, and endurance strength/0.2 pct proof stress ratios have been determined jbr a range of Cu(Ni), Cu(Si), and S.R.0. Cu(Au) solid solutions. Some douht is cast on simple cross slip models of fatigue hardening in view of opposite composition dependencies of hardening displayed by Cu(Si) and Cu(Au). The temperature dependencies of hardening also are the opposite of predictions made on the basis of a cross slip model. A correlation apparently exists between the fatigue strength/0.2 Pc~ proof s1.re.s~ ratios and rates of fatigue hardening. An increase in PS/PS due to alloying or temperature change is accompanied by a decrease in hardening rate, and vice versa. In recent years there has been much interest in the determination of the dislocation structure of fatigued metals and alloys. The accumulated evidence, e.g., Refs. 1 to 5, suggests that the structure may be dependent on the stacking fault energy, 7, of the fatigued metal in the same way that fatigue hardening rates have also been shown to apparently depend on u .6' 7 The above research followed the various earlier theories relating crack nucleation to ease of cross slip, e.g., Refs. 8 to 131 so "ggesting that y may indeed be the parameter of principal significance in all facets of the fatigue process. However, comparatively little attention has been paid to correlating engineering fatigue data with observations of the above type. Certainly, it would be useful if potential engineering fatigue performance could be assessed from a knowledge of easily determined alloy properties, and the present research originated from this standpoint. TO investigate the widest Possible range of 7 would require the use of two solvent bases, e.g., aluminum and copper, but a reasonable coverage can be provided by copper-based solutions alone. Therefore, it was decided to work with Cu(Ni) and Cu(Si) solid solutions, the approximate stackillg fault energies of which are given in Table I. The y range extends from low, Cu(7.5 at- Pet Si), to moderately high in Cu(2-5 at. ~ct ~i) and two of the Cu(Ni) alloys. The values listed in Table I should be regarded as qualitative only, being derived as follows. Dillamore and smallman14 quote a value of 85 i 30 erg.cm-2 for the stacking fault energy of pure copper, based on an earlier value due to Howie and swannl5 corrected by Brown's formula.'' Since the ratios (alloy)h(pure copper) have been reported17,18 for Cu(Ni) alloys containing up to 30 pct Ni, approximate ) values for these alloys can be computed, and a rough estimate of 7 for Cu(50 at. pct Ni) obtained by extrapolation. The relatively low y value obtained in this way for Cu(50 at. pct Ni) coincides with the observation of Nakajima19 that the stacking fault probability is a maximum at this composition. Likewise, the y values for the three ~u(~i) alloys are estimates based on values given by Swann and Nuttingo corrected on the basis Of Brown's estimate that the true 7 values are probably 2.3 times greater than those originally computed. In addition to the above alloys it was decided to investigate short-range ordered (s.R.O.) CU(AU) alloys containing up to 25 at. pct Au. This last alloy has been shown to have a well-defined planar arrangement of dislocations when deformed,21,22 probably due to cross slip being restricted by the S.R.O. Engineering fatigue data was to be represented by the determination of endurance strengths, and these were to be correlated with fatigue hardening and mechanical property data. EXPERIMENTAL I, order to study the desired properties and property changes, the following alloys were prepared: Cu(2.5 at. pct Si), Cu(5.0 at. pct Si), Cu(7.5 at. pct Si), Cu(5.0 at. pct Ni), Cu(25.0 at. pct Nil, Cu(50.0 at. pct Ni), Cu(5.0 at. pct AU), Cu(15.0 at. pct AU), Cu(25.0 at. pct AU). The copper and gold were zone-refined, while the silicon was semiconductor grade. The nickel was of 99.95 p,t. purity.* All alloys were induction-melted in a *Kindly supplied by the International Nickel co. helium atmosphere, appropriate precautions being taken to avoid segregation in the Cu-Au series. Rod stock was obtained by rolling and swag,ng. A few Bridgman single crystals were grown for fatigue-hardening studies, but most material was machined into polycrystalline fatigue speciments of the design shown in Fig. 1, and into polycrystalline tensile and fatigue-hardening specimens of simple cylindrical design. All specimens except Cu(Au) were annealed; the latter were quenched from above T, to produce short-range order. A few of the quenched alloys were examined for long-range order by step-scanning over

Jan 1, 1969

SEC. 1. The membership of the Institute shall comprise six classes, namely: 1. Members; 2. Honorary Members; 3. Senior Members; 4. Associates; 5. Junior Members; 6, Rocky Mountain Members. All shall be equally entitled to the privileges of membership, excepting that no member of any class whose residence shall be outside of the United States of America, except those residing in Mexico and Canada, shall be entitled to vote. SEC. 2. Members: A person to be eligible for election or transfer into the class of Member must be at least 27 years of age and must have had at least six years' employment in the practice of engineering, mining, geology, metallurgy, or chemistry, during at least three years of which he must have held positions of responsibility in one or more of these fields. This shall not apply to Rocky Mountain members. SEC. 3. Honorary Members: Each candidate for Honorary Membership must be recommended by at least ten Members and must be elected by ballot at a meeting of the Board of Directors by the unanimous vote of the Directors present; provided, however, that the number of Honorary Members shall at no time exceed twenty. Such election shall automatically act as a transfer of such member from any other class of membership to which he may belong. SEC. 4. Senior Members: The Directors may in their discretion place on the Honor Roll of Senior Members and transfer from any other class of membership other than Honorary Membership the name of any Member or Associate who has reached the age of seventy years and who has paid dues for thirty years, and for good reasons in • special cases may vary the age or number of years. SEC. 5. Junior Members: A person to be eligible for election to the class of Junior Member must be qualified through education or experience to hold a subordinate position in engineering, mining, metallurgical, geological or chemical work. He shall be not more than twenty-seven years of age at the time of election. The rights of the present Junior Associates shall continue until the same expire by limitation of time. SEC. 6. Associates: A person eligible for election or transfer into the class of Associate shall be one, who, in the opinion of the Committee on Admissions and the Board of Directors, is suitable for such election or transfer by reason of his interest in or connection with mining, geology, metallurgy, or chemistry. SEC. 7. Rocky Mountain Members: Membership in a special class of life memberships without annual or other dues and without right to receive the printed literature distributed to other members or the right and privilege of wearing the official badge of technical members, is given to all members of the Rocky Mountain Club at the time of consolidation. These special Rocky Mountain memberships shall be claimable by any member of the Rocky Mountain Club, not already a member of the Institute,

Jan 1, 1929

By E. S. Bardwell

TWENTY years ago, W. T. Burns, in his paper presented at the Butte Meeting of the Institute, discussed the general scheme then in use in the electrolytic copper refinery of the Anaconda Copper Mining. Co. at Great Falls, Mont., for removing impurities from tank-room electrolyte and controlling its acid content. Since then marked changes have taken place in copper-refinery practice at Great Falls. The electrolytic copper refinery in use in 1913 has been replaced by a new and entirely modern plant capable of producing up to 27,000,000 lb. of cathode copper per month. With the building of the new plant in 1916, the treatment of converter anodes was discontinued. At first the substitution of refined anodes for converter anodes resulted in a decrease in the impurity content of the anodes, but as time went on, changes in metallurgical practices at the smelter resulted in substantial increases in the impurity content of the anodes. The leaching of the silver slime to remove copper before shipment to Raritan for treatment further added to the purification problem. The fact that the scheme of purifying electrolyte which Mr. Burns described in his paper' has proved adequate for our needs under a wide variation of conditions speaks well for its essential soundness.

Jan 1, 1933

By D. O. Noel

IT is, of course, expected that manufacture of the various metal powders should involve numerous methods adapted to the specific characteristics of the metals themselves. Several methods for powdering a particular metal may be available, but the physical characteristics of the powder as produced by the several methods may be quite different. In the final analysis, the application of the metal powder dictates the physical properties that the metal powder must possess, and this, to a very large extent, will determine which of several possible methods of manufacture is adopted. Sometimes powder of the same metal is produced by more than one method, each powder having specific characteristics that make it particularly suitable for its application. For purposes of classification, the various methods of powdering metals can be grouped as follows: 1. Machining. 2. Milling (by ball mills, stamps, attrition mills, etc.). 3. Shotting (pouring molten metal into water, air, etc.). 4. Granulation (by stirring molten metal while solidifying). 5. Atomizing (disintegrating by steam, compressed air, etc.). 6. Condensation of metal vapor. 7. Reduction of oxide powders. 8. Chemical precipitation. 9. Electrolytic deposition. 10. Sintering (for producing alloy powders). 11. Formation of an alloy followed by dissolving or otherwise remov-ing one of the alloying constituents.

Jan 1, 1938

By Marcel R. Daly

In a preceding paper1 the writer has pointed out some apparent relationship between the distribution, on the surface of the globe,, of the known hydrocarbon deposits and the disposition of the principal zones of deformation of the earth's body (geosynclines). He wishes to present some further remarks on this subject. Petroleum deposits, or their derivatives or descendants, are found through the whole range of sedimentary strata, from the pre-Cambrian to the Quaternary. For instance, the prc-Beltian (Shuswap) series of the Canadian Cordillera are interbedded with limestones which are sometimes rich in carbonaceous matter (Sicamous limcstone); and the Beltian system of the same region contains layers of argillitcs and dolomitic limestones which are equally high in carbon content.2 This carbon may be interpreted as the last remnant of hydrocarbons previously contained in the rocks. On the other hand, the actual formation of hydrocarbons under conditions that would eventually permit their deposition in modern sediments is conceded by some geologists.3 Between these two extreme limits, bitumens are found indifferently in all sedimentaries. Thcy constitute a continuous series, some kind of a large family, whose individual members may be entitled to a community of origin and probably represent the different stages of evolution of the primitive, parent matter. The kinship between petroleum and such substances as asphalt, ozocerite, manjak, grahamite, albertite, etc., is well known; and E. H. Cunning-gam-Craig has recently shown how intimately shale fields and oil fields are connectcd.4 For this reason, no distinction is made in the present

Jan 1, 1918