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By AIME AIME

A discussion of the Papers by Prof. H. Hubert, Liege, Belgium ; Mr. Tom Westgarth, Middlesbrough, England ; and Mr. K. Reinhardt, Dortmund, Germany, presented at the London Meeting, July, 1906, and printed in Bi-Monthly Bulletin, No. 12, November, 1906; pp. 910 to 930, 971 to 987, 1037 to 1163. MR. ADOLPH GREINER, Seraing, Belgium :-I have nothing special to add to Professor Hubert's paper except to say that there are some little things that it would be well to have cor-rected when the paper comes to be published. In dealing with the thermal efficiency of the engine, you will find that the 29.84 per cent was a very high one. Professor Hubert has forgotten those engines built under the Cockerill type, but he has referred to them in Appendix II. At our works at Cockerill we have built 63 engines, giving 63,000 h.p., and the other companies who have received licenses have built 113 engines, making 103,000 h.p., and aggregating 176 engines and 166,000 h.p. Eight years ago I had the pleasure of giving to the Institute the results obtained up to that time. Since then a good many engines have been constructed. In 1898 I thought a blast-furnace producing 100 tons of pig iron would allow 3,000 h.p. Professor Witz and Professor Hubert show that with the same production of pig the new engines take 3,800 h.p. out of the gas. At present at Cockerill we make 700 to 800 tons of pig iron per day, and we hope to have 26,000 h.p; in a few years. At present we have only half of that in gas-engines, but we hope to have in five or six years all the gas out of these furnaces to the number of 25,000 or 26,000 h.p. MR. Tom WESTGARTH, Middlesbrough, England:-My contribution is not a paper in the ordinary sense of the word, because I am sure you will agree with me that what I have written is only supplementary to the other two papers. The notes are schedules of the larger-size gas-engines built by the engine-makers, of 500 h.p. and upwards. If you look at the schedules you will find that in England gas-engines have be-

Jan 1, 1907

By P. H. Metzger, D. W. Fuerstenau

The activation of sphalerite was found to occur at a much lower rate with Pb++ then with Cut++ or Ag+. To prevent activation with Pb++, the ratio [m in solution must approximate 103. An example is given illustrating how this condition is met in practice through the addition of zinc sulfate and soda ash. In selective lead-zinc flotation, the mill operator, especially the one who is concentrating a partially oxidized ore, often must add zinc sulfate and/or soda ash for effective depression of the sphalerite. In the present paper the authors show how this practice prevents the activation of sphalerite in the presence of Pb++. A number of years ago Gaudin (1) postulated that Zn++ might control the activation of sphalerite with Pb++ through competitive adsorption. However, recent experimentation has shown the activation of sphalerite with Ag+ and Cut++ to be a chemical reaction in which silver or copper ions replace zinc in the sphalerite lattice through the formation of a more insoluble sul-fide (2,3,4) Thus, if activation with Pb++ is similar to that with Ag+ or Cu t+, zinc salts should control the activation of sphalerite not through competitive adsorption but because the ratio of [zn++/Pb++] in solution regulates the extent of the chemical exchange between Zn++ and Pb++ in the solid phase. The objective of this investigation has been to study the kinetics and equilibrium conditions for the uptake of Pb++ by sphalerite and to investigate the prevention of lead activation with zinc salts. BASIC PRINCIPLES Sphalerite activation has been shown to be a replacement reaction wherein a less soluble compound is formed at the expense of the more soluble zinc sul-fide (2,3,4) For example, if sphalerite is placed in an aqueous silver nitrate solution, ZnS gives to the solution more S= than can exist together with Ag+, and hence the following reaction takes place: ZnS + 2 Ag+? Ag2 S + Zn ++; k = [zn ++]/[Ag ++]2 = 10 26 (1) Therefore, ZnS will dissolve in the presence of Ag+ and activation of sphalerite with Ag+ will proceed after monolayer coverage by solid state diffusion until equilibrium conditions are reached in the system (2, 4) Because of the large difference in the solubility of ZnS and Ag2S, zinc salts cannot affect the reaction unless a complexing agent, such as cyanide ions, is present to complex Ag+ more tightly than Zn++ . By complexing Ag+ and Zn++ in solution, the uptake of Ag+ by sphalerite can be regulated by controlling the ratio m. . Experimentally (2) it was found that the activation of sphalerite by Ag+ could be prevented through the addition of NaCN if this ratio reached a value of approximately 10 26. The mechanism of sphalerite activation with copper salts is given by the following reactions: ZnS + Cu ++ ? CuS + Zn + + ; (2) k = [Zn++]/[Cu++] = 10 11 ZnS + Cu + ? Cu2S+ Zn++; (3) Experimentally Mao (3) found that the activation of sphalerite with Cu++ or Cu + was prevented if the ratios expressed in Equations 2 and 3 were approximately l09 and l022, respectively, with cyanide ions as the deactivator. Although zinc salts do not affect the activation of sphalerite with silver or copper ions in the absence of a complexing agent, activation with lead ions theoretically can be controlled by the addition of zinc salts because of the relatively small differences between the solubility of ZnS and PbS (5). Equilibrium

Jan 1, 1961

By E. Parthe, J. P. Pemsler

TWO references can be found in the literature concerning the ternary system uranium-tantalum -carbon. C. H. Schramm, P. Gordon, and A. R. Kaufmam reported in this Journal1 on the existence of the ternary carbide "UTa10C4." They also report a second face-centered-cubic carbide phase in the system U-Ta-C, which they denote as "white" phase. The publication includes a reproduction of a Debye-Scherrer powder photograph of "UTa10C4" and a list of the sin2 0 values of this compound. H. Nowotny, R. Kieffer, F. Benesovsky, and E. Laube2 report the complete solid solubility between TaC and UC with a B1 structure. Since the ternary phase "UTa10C4" lies very close to the binary system Ta-C, and the established phase Ta2C with a C27 structure had not been mentioned by Schramm et al., it was thought worthwhile to compare the patterns of "UTa10C4" with Ta2C. The strong lines of the given pattern were indexed on a hexagonal unit cell with the approximate cell parameters a = 3.09A and c = 4.93A. These are the values reported for Ta2C in the literature.3 The correspondence between reported and calculated sin2 8 values may be studied in columns 4 and 5 of Table I. The agreement is fair, but there remain weak lines which cannot be assigned to the hexagonal unit cell. The extinctions correspond to those of Ta2C, but a comparison of the calculated and observed intensities of the Ta2C lines (columns 2 and 3) with those of the corresponding lines of "UTa10C4" (column 6) show occasional deviations. To clarify this situation, four new samples were prepared. The compositions of these samples were chosen in such a way as to observe any existing ternary phase in the system TaC-UC-U-Ta. The samples were arc melted in an inert atmosphere and annealed at 1100°C for 36 to 72 hr. Compositions of the samples determined by chemical analysis are given along with the results of X-ray investigations in Table 11. The following conclusions may be drawn from these data: a) No ternary compounds occur in the section TaC-UC-U-Ta of the ternary system Ta-U-C. The "white" phase reported by Schramm et al. corresponds to a solid solution between TaC and UC. Only one three-phase field exists: C27-B1-A2. (Both tantalum and ? uranium have body-centered-cubic A2 structures.) The a uranium observed in sample 4 transformed from the high-temperature ? phase on cooling. b) The phase Ta2C with a C27 structure extends into the ternary system. "UTa10C4" is, therefore, a uranium-enriched Ta2C. Good agreement is ob-

Jan 1, 1960

COMMITTEES. Iron and Steel. Albert Sauveur, Chairman. A. A. Stevenson, Vice-Chairman. Herbert M. Boylston, Secretary, Abbot Bldg., Harvard Sq., Cambridge, Mass. LOCAL COMMITTEES. Program Committee.-A. A. Stevenson, Chairman. Herbert A3. Boylston, J. E. Johnson, Jr., Henry D. Hibbard, E. Gybbon Spilsbury. Reception Committee.-J. R. Johnson, Jr., Chairman. Felix A. Vogel, William R. Walker. Dinner Committee.-E. Gybbon Spilsbury, Chairman. The opening session was held on Thursday morning, Oct. 16, 1913, at the Institute Headquarters in the Engineering Societies Building, 29 West 39th Street, New York, N. Y., and was called to order by President Rand, who addressed the meeting briefly before presenting Albert Sauveur, who responded to the President's address, and presided at the meeting. The following papers were then presented in oral abstract by their authors or authors' representatives: The Cleaning of Blast-Furnace Gas, by W. A. Forbes. Discussed by S. K. Varnes, H. N. Diehl, F. H. Wagner, Joseph Hartshorne, S. B. Marshall, J. W. Richards, J. E. Johnson, Jr., W. A. Forbes, and others.

Jan 12, 1913

Discussion of "The Ordering Transformation in Titanium-Aluminum Alloys Containing up to 25 at. pct Aluminum" by F. A. Crossley, Trans, TMS-AIME, 1968, vol. 242, pp. 726-30. Dr. Blackburn, in his response, pointed out that the c/a ratio of the Ti-26 at. pct A1 alloy quenched from 900°C is 1.6006 and not 1.5965 as plotted in Fig. 19. An error in transcription was made in preparing Table V of Ref. 1 (F. A. Crossley, Trans. TMS-AIME, 1966, vol. 236, p. 1174). The corrected Fig. 19 strengthens rather than weakens the argument that a martensitic transformation occurs in alloys containing from 15 to 18 at. pct Al. A Study of the Factors Which Influence the Rate Minimum Phenomenon During Magnetite Reduction, by P. K. Strangway and H. U. Ross, Trans. TMS-AIME, 1968, vol. 242, pp. 1981-88. Page 1883 Reverse Figs. 5 and 6. Sigma—Its Occurrence, Effect, and Control in Nickel-Base Superalloys, by J. R. Mihalisin, C. G. Bieber, and R. T. Grant, Trans. TMS-AIME, 1968, vol. 242, pp. 2399-2414. Pages 2403, 2407, and 2414 Arrows should appear on Figs. 4 and 9; a sigma is missing from Table IV; line 2, page 2414, change "case" to "cast". These are published correctly in the bound volume. Index, December Issue There were a few omissions in the Author Index. These have been corrected and published properly in the bound volume.

Jan 1, 1970

By Koert D. Burnham, John G. Broughton

WOLLASTONITE in Essex County, New York, occurs as a typical contact mineral in a series of rocks metamorphosed by anorthosite. Sole current use is in various types of electric welding fluxes. Its uniform lathlike shape suggests its use as a specialized filler.

Jan 1, 1944

By Arnold Hoffman

A RESPONSIBLE steel executive recently declared that scrap shortages, despite fantastic prices reaching up to $50 per ton, are responsible for the loss of 140,000 tons of steel a month and that in March 1947 alone 25 more steel furnaces could have been operating were it not for scrap scarcities. His answer to this serious situation was to ask for a speedier flow of scrap and also abolition of Government control over pig iron distribution. It would be more logical, perhaps, if an answer to this growing problem of scrap deficiency were sought within the steel industry itself. As long ago as 1933, L. B. Lindemuth, a consulting steel metallurgist, warned the steel industry that a shortage of scrap was inevitable and that beyond 1938, adequate supplies for open-hearth furnaces could not be expected. The outbreak of war, with consequent phenomenal demands on the industry, accelerated production of steel and further worsened the scrap situation. Today we are suffering from a condition which could have been prevented had the industry been more far-seeing and provided for an inevitable contingency. However, better late than never, and measures can now be taken to alleviate permanently scrap shortages in the future. This can be done by greater utilization of heavy sinter which experience proved is an excellent substitute for scrao and lump ore.

Jan 1, 1947

By B. M. Larsen

Jan 1, 1948

By B. M. Larsen

Jan 1, 1948

By E. H. Timmerman, A. F. van Everdingen, J. J. McMahon

The prevent paper contains a method which combines the material balance equation' with the water influx equation' to obtain reliable values for the active oil originally in place and a quantitative evaluation of the cumulative water influx. The method is illustrated by an application to a reservoir without original gas cap. In the absence of an original gas cap. results may be obtained using only field production and pressure data, PVT analyses. and a minimum of subsurface information. CHARACTERISTICS OF RESERVOIR AND RESERVOIR FLUIDS Production in the field under review is obtained from the top of the Wilcox formation of Eocene age, at a depth of approximately 8,100 ft subsea. The structural map, Fig. 1, shows that the accumulation, half elliptical in shape with the long axis in east-west direction, is trapped to the north and on the upthrown side of a normal fault. A number of east-west faults with additional minor faulting in random directions are found in the general area, and seismic information and production performance indicate in this particular case the existence of a second fault a short distance downdip, with a strike more or less parallel to the fault controlling the accumulation. It is estimated that 1,830 acres were originally underlain by oil and that the maximum thickness of the original oil column, about 37 ft, was only slightly greater than the maximum thickness of the oil-bearing sand. Maximum net sand thickness was estimated at approximately 26 ft. From logging and subsurface information the gross sand volume has been placed at 37.400 acre-ft. which reduces to about 27,500 acre-ft after probable non-productive intervals have been deducted. The following table presents laboratory analyse; data for the Wilcox sand cores. Average Average Samples Considered Permeability Porosity All Samples 236 md ..19.9percent Samples with k>l md 256 md 20.5 per cent Samples with k>8 md 275 md 20.9 per cent Interstitial water was estimated at 15 per cent. The initial gas-oil ratio was approximately 900 cu ft/bbl. and the initial shrinkage factor was determined by the laboratory to

Jan 1, 1953

THE members arrived at Ticonderoga, N. Y., at noon, Tuesday, October 15th, and were received by Mr. Cyrus Butler, Chairman of the Local Committee of Arrangements. During the afternoon the works of the American Graphite Company and the Horicon Iron Company were visited under the guidance of Mr. Butler, President of both companies, and of Mr. William Hooper, Superintendent. An excursion was then made, in carriages, to old Fort Ticonderoga, on Lake Champlain, after which the party were driven to the Rogers Rock Hotel, on Lake George. The first session of the Institute was held in the parlor of time hotel on Tuesday evening. Mr. Eckley B. Coxe, President of the Institute, opened the proceedings with the following address: I shall ask your attention, this evening, to a few reflections upon the subject of mining engineering as a profession in the United States, its past, its present, and its future, and its duties and oppor¬tunities with reference to the proper development of our great min¬eral resources. Thirty years ago, there were scarcely any mining engineers in this country, and but few in England, and there were no institutions where young men could be educated for the profession in the Eng¬lish language. France and Germany have been able for about a century to boast of mining schools of a high character, that number among their graduates such men as Humboldt, Weisbach, Rittinger, Combes, and Gruner. Of the few we then had worthy of the name of "mining engi¬neer," some had studied in the continental academies, and others were graduates in the school of practical experience, and had learned their profession in mines and smelting-works. Their work con¬sisted principally in making surveys and maps of mines and mining properties, geological reports, and analyses of ores ; but the mining engineer whom we often meet with now, who has studied chemistry, physics, mineralogy, geology, mechanics, and drawing; who is more or less familiar with machinery and its construction, and with the practical management of mines or smelting-works, and who is an expert in some one branch of his profession, would have been very difficult if not impossible to find in the United States. The induce¬ments held out to ambitious and talented young men to enter the

Jan 1, 1879

Jan 1, 1879

By E. Gybbon Spilsbury

(Pittsburg meeting, March, 1910.) THE recovery of gold and silver from their ores by means of the cyanide process has been so successful in the last few years that any radical improvement would seem impossible; yet the appliance to which I wish to call attention in this paper is really a radical departure from the methods now in general use. The most modern and approved of these, known as the all-sliming method, depends for its success on the grinding of the. ore so fine that practically 90 per cent. of it will pass through a 200-mesh screen. The slimes thus produced are then agitated and aerated in tanks of various types. The main object of this treatment is to insure such a thorough admixture of the pulp and solution that every particle of the ore is surrounded by a volume of solution sufficient to insure the dissolving of the whole of the gold- and silver-content. In addition, in order to expedite the action of the cyanide, and to oxidize such elements as would, if left in their active state, become cyanicides, air is blown in under pressure. In the Pachuca tank, this air is the active and sole means of agitation. The chief objections to all the methods off agitation used heretofore are the expense of operating and maintaining the mechanical devices for keeping the pulp in suspension, and the length of time required to obtain a fairly complete extraction. of the values. These objections are inherent to any method of agitation effecting a circulation of the pulp and the solution together, by giving the whole mass a circular movement, as in the low-tank system, or a vertical circulation, as in the Pachuca-tank system. In both methods, the particles of ore are kept traveling in the same direction as the solution, and with very little difference of speed; so that, while the whole mass is in

May 1, 1910

NEW MEMBERS The following list comprises the names of those persons who became members during the period of Apr. 10, 1917, to May 10, 1917. ANDERSON, GEORGE K., JR., Supt., Iron Ore Mines, The Low Moor Iron Co. of Va., Longdale, Va. AVERY, DAVID, Met Collins House, Collins St., Melbourne, Vic., Australia. BATES WILLIAM T., Shift Foreman, American Zinc Co. of Tenn., Mascot, Tenn. BIRD, ELMER, Min. & Civil Engr P. O. Box 1483, Boise, Idaho. BLACKBURN, JOSEPH R., Vice-Pres. & Genl. Mgr., Austen Coal & Coke Co., Austen, Preston Co., W. Va. BOTSFORD, FRANK P., Asst. Genl. Supt., Eastern Mesaba, Pickands Mather & Co., Gilbert, St. Luis Co., Minn. BRADEN, SPRUILLE, Min. Engr., Andes Exploration Co. of Maine, Casilla 83-D, Santiago, Chile South America. BROWNE, DAVID G., Mill Designer, New Jersey Zinc Co., 55 Wall St., New York, N. Y. BRUDERLIN, EMIL J., Met. Engr., Ohio & Colorado Smelt. & Ref. Co., Salida, Colo. CAMPBELL, DONALD C., Min. Engr., Campbell Wells & Elmendorf, 114 James St., Seattle, Wash. CARRIGAN, J. J., Asst. Genl. Supt. of Mines, Anaconda Copper Min. Co., Butte, Mont.

Jan 6, 1917

By William E. Ford, Edward Salisbury Dana

The important BARITE GROUP is the only one among the anhydrous sulphates and chromates. Mascagnite. Ammonium sulphate, (NH4)2S0,. Orthorhomhic. Usrially in crusts and stalactitic forms. p = 1.523. Occurs about volcanoes, as at Etna, Vesuvlus, etc. Taylorite. 5K2SOa.(N&)ySOd. 111 small compact lumps or concretions. From the guano of the Chincha Islands. Thenardite. Anhydrous sodium sulphate, Na2S04. In orthorhombic crystals, pyrarnidal, short prismatic or tabnhr; also as twins (Fig. 384, p. 160). White, to brpwnish. 0 tically +. p = 1.477. Soluble in water. Often observed in connection with salt lates, as on the shores of Lake Balkhash, Central Asia; similarly elsewhere; also in South America in Tarapaca, Chilc. In the United States, forms extensive deposits on the Rio Verde, Aria. In Cal., at Borax Lake, San Bernardino Co. Aphthitaiite. Arranite. Glmerite. (Ii,Na)&O1. Rhombohedral; also massive, in crusts. Color white. From Vesuvius, upon lava; at DouglashaU near Weateregeln, Ger- many, in hloditc; Stassfurt, Germany; Rocalmuto, Sicily.

Jan 1, 1922

Institute of Metals Division Iron and Steel Division Extractive Metallurgy Division Council J H Scaff (IMD) Chairman, Robert W Shearman, Secretary, J S Smart, (IMD), P T Stroup, (EMD), A W Schlechten, (EMD), J S Marsh, (ISD), A W Thornton, (ISD), M E Violin, (MED), D S Eppelsheimer, (MIED) Journal of Metals Editorial Advisory Committee J S Smart, Jr, Chairman, W A Dean, J C Kinnear, Jr, T D Jones, Evan Just, John Marsh, M Tenenbaum Pacific Northwest Regional Conference A Y Bethune, General Chairman, Frank N Marr, Chairman, General Arrangements, R J Lapee, Chairman, C P Love, (EMD Program), W M Armstrong, Chairman, Physical Metallurgy Program, L W Heinzinger, Chairman (ISD Program), J P Spielman, Chairman, (MIED Program) New England Regional Conference K H Mairs, Chairman, W A Backofen, Vice-Chair¬man, Delmar E Trout, Secretary, G W Coleman, Treasurer, F H Wilson, Past Chairman, Members at Large Sidney Siegel, Boston, G F Donahue, Connecti¬cut Representatives from Connecticut Frank Chudy, J E Chafey Representa¬tives from Boston N L Reed, E Gordon

Jan 1, 1955

By H. B. Bell, P. C. Lidster

A study has been made of the use of ThO2-Y2O3 solid electrolytes to determine activity of chromium in Fe-Cr and Ni-Cr alloys in the temperature range 1300° to 1700°K. This method has been shown to give results which agree with the best vapor pressure measurements. SEVERAL investigations1"5 have been made of chromium activities in Fe-Cr alloys. Most of these have been made by vapor pressure measurements using knudsen cell techniques while one has been made using gas equilibration with H2/H2O gas mixtures. In the present investigation electromotive force measurements have been made on this system using a thoria yttria solid electrolyte. This system was -chosen to establish the technique of measurement at low oxygen potentials, before extending it to Fe-Ni-Cr alloys. The cell used was Pt Cr • Cr2O3 ilThO2 • Y2O3 llalloy • Cr2O3 IPt Since the oxygen pressure of the chromium-chromic oxide mixture lay in the range 10"19 to 1027 atm in the temperature range investigated, thoria yttria electrolytes were used. It was soon found during the investigation that considerable care was required to prepare satisfactory electrolytes and a study was made to find the best method of preparing pellets of TI1O2-Y2O3 solid solution of as near theoretical density as possible. Various compositions in the range 2 to 15 mole pct Y2O3 were studied but the experimental measurements were made with electrolytes containing 4 to 5 pct Y2O3. The method of preparation finally adopted was to use thorium oxalate and yttria as raw materials. The thorium oxalate was decomposed at 900°C for 6 hr to give a reactive powder. This powder was then mixed with the appropriate amount of yttria and ground in an agate mortar for about 4 hr. The powder was moistened with absolute alcohol as a lubricant and pressed in a metal die at a pressure of 7 tons per sq in. The pellets were then heated at 1100°C for 24 hr followed by 24 hr at 1250°C. After this firing cycle the material was reground and repelleted and again fired at 1100° and 1250°C followed by heating for 7 days at 1600°C. It was found in later experiments that a further firing of 4 hr at 2000°C improved the density further and gave pellets of only 2 pct porosity. After firing, the pellets were polished on emery paper and finally with the 2 µ diamond paste. The polishing was followed by a final firing of 24 hr at 1500°C. Investigation showed that this final treatment minimized reaction between the electrolytes and chromium oxide. It was believed that this was because of a lowering of the surface energy of the electrolyte surface. Two types of investigation were carried out to check that the pellets were satisfactory oxygen ion elec-

Jan 1, 1970

By Amitava Gangulee, Michael B. Bever

The effects of changes in short-range order on some thermodynamic, electrical, and mechanical properties of the silver-rich Ag-Mg solid solutions have been investigated. The heats of formation at 273°K of several alloys after two different thermal treatments were measured by liquid metal solution calorimetry. Their electrical resistivities were measured at temperatures ranging from 4° to 773°k. Tensile tests and microhard-ness measurements were carried out at room temperature. An effective short-range order parameter and an effective interaction energy are defined. The measured changes in the properties are interpreted in terms of these quantities. The short-range order parameter is evaluated separately from calorimetric and X-ray data; the results are in fair agreement. Increasing short-range order lowers the resistivity of- the silver-rich Ag-Mg alloys but does not measurably affect the temperature dependence of the resistivity. Short-range order increases the yield stress of these alloys but does not affect the ultimate tensile stress. Changes in the effective short-range order parameter independently obtained from measured changes in the heat of formation, resistivity, and yield stress are in fair agreement. THE thermodynamic, electrical, and mechanical properties of solid solutions have been investigated as functions of composition in many alloy systems, but the effects of configurational variables, such as short-range or long-range order, on these properties have received much less attention. The silver-rich terminal solid solutions in the system Ag-Mg are well-suited for the investigation of the effects of order. The composition of these solid solutions may be varied over a range extending to about 27 at. pct Mg.1 Appreciable short-range ordering is likely to take place in these solid solutions; the degree of short-range order can be varied by suitable thermal treatments. In the alloy Ag3Mg long-range ordering is possible.2 This paper is primarily concerned with the effects of short-range order on some thermodynamic, electrical, and mechanical properties of the silver-rich Ag-Mg solid solutions.-The long-range ordering transition is the subject of a concurrent paper.3 1) EXPERIMENTAL PROCEDURES 1.1) Preparation of Specimens. Ag-Mg alloys containing up to 26.4 at. pct Mg were prepared by melting 99.99 pct pure Ag (obtained from Baker Chemical Co.) and 99.99 pct pure Mg (obtained from Eastman Chemi- cal Co. or Johnson Mathey & Co.) in graphite crucibles under molten potassium chloride. The solidified ingots were homogenized at 823°K for 10 days in evacuated Vycor capsules. A surface layer 6 in. thick was then removed by machining. The ingots were swaged into rods (2.5 mm diam) which were drawn into wires (1.0 mm diam). The wire specimens were annealed at 773°K for 24 hr in vacuum and either quenched into iced brine or cooled to room temperature over a period of 15 days. The average grain diameter (obtained from the linear intercepts) was about 0.1 mm. 1.2) Calorimetry. The heats of formation of the alloys were measured in a tin solution calorimeter as the difference in the heat effects of alternate additions of samples of an alloy and the mechanical mixture of its component elements. The additions were made from 273°K to the bath at about 623°K. The heat effect on addition of the alloys was approximately 5.5 kcal per g-atom. The procedure and the method of calculation have been described.4 1.3) X-Ray Diffraction. Short-range order parameters of two alloys were calculated from diffuse scattering intensities,' obtained with briquettes made from powdered specimens. A GE-XRD 5 diffractometer with filtered copper radiation was used. The absolute intensities were based on calibrations with paraffin. 1.4) Resistivity Measurements. The electrical resistivities were measured by a potentiometric method in which the potential drop across the specimen was compared with that across a standard resistance. For measurements below room temperature, the specimens were immersed in liquid helium (4°K), liquid nitrogen (78°K), dry ice and trichloroethylene (195°K), or ice and water (273°K). Measurements above room temperature were made on specimens held in a furnace under helium or in vacuum. The resistivity measurements were reproducible to ±0.5 pct or less. 1.5) Mechanical Tests. Tensile tests were carried out at room temperature with a Tinius-Olsen XY elec-tromatic Universal testing machine. Wire specimens (nominal gage length 1 in.) were used. The strain was measured with an extensometer, which had a sensitivity of 4 x 10-5; the strain rate was 10-3 min-1. Microhard-ness measurements were made with a square-pyramid indenter and a 100-g load.11 2) RESULTS AND DISCUSSION All measurements were made on two parallel sets of specimens, one quenched and the other slowly cooled from 773°K. The reported values are the averages of at least three measurements. In the range of magnesium concentration substantially below that of the composition Ag3Mg, quenched alloys have less short-range order than slowly cooled alloys. As the magnesium concentration approaches that of Ag3Mg, slow cooling develops long-range order. Quenching sup-

Jan 1, 1969

By H. C. Rickaby

BY August 1944 Canada expects to be shipping 56 percent hematite ore from its new Steep Rock iron mine, via Port Arthur on Lake Superior, to the steelmaking centers in Canada and the United States. This is indeed welcome news to steel men, especially if they operate open hearth furnaces, as the Steep Rock ore is a high-grade lump and will be valuable as charge and feed ore. But better news is the fact that this first big producer of high-grade hematite ore in Canada, since the exhaustion of the Helen mine in the Michipicoten area north of Lake Superior in 1918, has a proved ore body of 16,757,000 long tons and a probable ore body of 14,000,000 long tons, thus giving an over-all total of 30,757,000 long tons and assuring production for a number of years to come.

Jan 1, 1943

By F. Robertson Jones

IF the tendency toward extending the scope of the workmen's compensation system to include life, health, accident, old age, and unemployment insurance for workers is not promptly altered, I believe there will be a complete breakdown of that system. This is not because of any objections, there may he to requiring industries to provide these additional forms of protection in whole or in part to their employees. It is rather because our workmen's compensation laws, their scale of benefits, and the administrative procedure under them are not adapted or suited to such situations. If the compensation principle is limited to its own proper sphere and is not enlarged so as to include all the ills that the flesh is heir to, it is practical, "workable, and beneficent. If it invades foreign realms, it is bound to grow into a veritable Frankenstein' which will harm principally those it 'is supposed to aid, and, at the same time, will promote waste, fraud, and Industrial demoralization. Compensation risks will become almost uninsurable; the cost to business will be intolerable; and the development of sound relief measures which will give to labor the protection now sought by the uneconomic device of enlarging the compensation law territory will be retarded.

Jan 1, 1934