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By W. F. Wheeler

IN the study of the coals of Illinois now being carried on by the State Geological Survey, an attempt is being made to determine the most satisfactory basis of comparison between different coals. The following discussion is based upon work done for the survey in the laboratories of the State University and under the general direction of Prof. S. W. Parr. " Pure coal " has been defined by Mr. A. Bement1 as ash- and moisture-free coal, and the use of this " pure coal " as a basis for comparing different bituminous coals has lately been much discussed among engineers in the middle West. By some the B.t.u. of the pure coal is being used to check calorimetric results, and to calculate the calorific value of different coal-samples from the same seam, for which purposes it is necessary to assume-first, that the composition and calorific value of pure coal from different parts of the same coal-seam are uniform, and, second, that these values remain constant after the coal is mined, both of which assumptions there are reasons to believe are inconsistent with the facts. Certain variables are included in pure coal, as ordinarily defined, and disregard of them may lead to serious error. In any event, where delicate shades of difference are involved, no sure interpretation of results can be made, unless these variables be eliminated. As a basis of comparison between coals, ash- and moisture-free coal is much to be preferred to " dry coal," and still more is it to be preferred to " moist coal," as ordinarily reported in analyses. There are, however, two constituents other than ash and moisture which are similar in effect to them, and which

Jan 1, 1908

By Arthur S. Dwight

From the latest and best literature on lead-smelting, little can be learned concerning the present state of the art of mechanical feeding in the United States. H. O. Hofman, in his Metallurgy of Lead (5th ed., 1899), briefly describes the main features of the system in use at Pueblo, Colo., and later (p. 235) says " the only successful mechanical feeding, as far as the writer is aware, is that found at the works of the Pueblo Smelting and Refining Co." H. F. Collins, in his Metallurgy of Lead and Silver (London, 1899), covers American practice pretty thoroughly; but as to mechanical charging, he says: "The German plan of taking off the gases by means of a small iron pipe suspended in the center, and the plan of charging by means of cup and cone, as in iron blast-furnaces, have both been tried, but have not found favor, chiefly on account of the difficulty of obtaining free access to the furnace-shaft for barring, etc., with such devices."' . H. W. Hixon, in his Notes on Lead and Copper Smelting (3d ed., New York, 1900), gives a description and drawing of the Hixon feeding device, as originally installed at East Helena. Evidence that this system of feeding has passed its experimental stage, and deserves more serious consideration than it has heretofore received, is furnished by two large plants—the Pueblo and the East Helena—of the American Smelting and Refining Co., where mechanical feeding has been in continuous and successful operation for a considerable period; one new plant now erecting at Salt Lake City, Utah, and one old one belonging to the same company, the El Paso works, now being rebuilt after a disastrous fire, in both of which mechanical feeding is to be a prominent feature ; one new plant of an independent concern at Torreon, Mexico, which will adopt mechanical feeding; and a number of other smaller plants, among

Jan 1, 1902

By Earle C. Waite

THE Industrial Minerals Division this year held no individual sessions of its own except the business meeting Tuesday afternoon. One session was held jointly with the Society of Economic Geologists, one with the Milling Methods Committee, and two with the Society of Economic Geologists and the Mining Geology Committee. At all of these meetings the attendance was better than usual and the Tuesday afternoon session, with nearly 400 present, probably set a new record for the Division. Joint sessions seem extremely popular when papers of mutual interest are presented. On Monday afternoon, mica was the predominating subject. The North Carolina mines provided most of the information presented, although the discussion brought out similarities with the New England mines. B. C. Burgess particularly stressed the fact that with the existing curtailment of mica from India it is necessary to get the most mica in the shortest time from the mines in this country. He said that the Colonial Mica Corp. hopes to have 1000 mines operating in the near future. This seems a great number, but when one considers that these mines employ from 3 to 28 men, mostly nearer the low figure, the output of each mine is relatively small. Although the price of mica is from six to ten times the prewar price, the yield of 8 to 150 lb. of mica per ton of raw ore does not provide high returns to the producer.

Jan 1, 1943

By AIME

After an adventurous past-four changes of government in thirty years -the whole of Silesia and attached coal territories have become part of the Polish State. The coal resources of this area are the biggest among the European countries. Under a surface area of 5700 sq km are about 100 coal seams, with a total thickness of 150 meters. According to German estimates, there are some 150 billion metric tons of coal ranging in thickness up to 14 m within a depth of 1500 m. The seams are mostly level, free from faults, with good top and bottom; the coal is of excellent quality, hard and clean; and mining conditions are favorable. The mines are worked at considerable depth by means of vertical shafts and operate with cage and skip hoisting. Before the war, the mines were up to date, equipped with modern machines. Among the European countries, output per man shift was the highest ? 1.9 to 2.1 metric tons ? and cost of production was the lowest.

Jan 1, 1949

THE first session of the Institute was held on Tuesday evening, September 16th, in the William Molson Hall, of McGill University, Dr. T. Sterry Hunt, Chairman of the Local Committee of Arrangements, in the chair. Dr. Hunt introduced Monsieur S. Rivard, Mayor of Montreal, who spoke as follows : GENTLEMEN: We welcome you with pleasure to our city, and we are proud to find that you have deemed it worthy of your visit. I understand that your association was founded in 1871 with some thirty courageous members, and that so valuable has it been esteemed, and so attractive was it found, that nearly one thousand have now enrolled their names as members and associates. But we must regard your profession as dating back to the stone age and mingling therewith ; how remote that is none of us can tell. Much of civilization is due to the discovery of metals, and the magnitude of our works to their widespread abundance. If you have not accomplished what the alchemists aimed at, which was to turn the ruder materials into gold, you manage, by your subtle skill, to turn stones into gold value. Europe has long since been-dug into and perforated with shafts and galleries in search of metals, and great wealth, and power, and comfort have arisen there-from ; but by an increase of knowledge, and more than European enterprise and energy, America is following rapidly in the race, and by means of natural advantages of a geological character has out-stripped the Old World. We are pleased to see you, gentlemen, as an evidence of the unity of this continent. Maps may have various delineations, but the veins and arteries of commerce and the nerves of science knit all together into one social organism with the same vital functions. We live here on the margin of the world, and can claim but a modest share in. the great works of modern times, but such as we have that can interest you we gladly offer for your observation.' Our Victoria Bridge may he considered appropriate, for without mining engineers to precede the civil and mechanical, no bridge would be there to-day. In truth, the same may be said of all works of metal, and of all that are executed by tools and machinery made of metal. The Mont

Jan 1, 1880

By O. G. Lellep

IN every country economic circumstances prescribe the method used to produce a commodity at lowest cost. In Pennsylvania a man's wages for working 4 hr buys a ton of coal wholesale; in Germany a laborer must work 40 hr, or ten times as long. In western Europe, therefore, conservation of fuel is of primary importance, and recent practices of burning lime and cement differ from those employed in the United States. This paper presents data collected during a trip through western Europe in 1953. Considered uneconomical, shaft kilns for burning cement disappeared in the United States two generations ago. But because required capital investment is low and operation greatly improved, shaft kilns are still used to some extent in Europe, where fuel costs are high, and are even included in designs for plants under construction. During the last 50 years shaft kilns have been maintained at the same physical size, while their output has been increased at least four times.

Jan 7, 1954

By AIME AIME

WILLIAM ("BILL") EMBRY WRATHER, recently elected to a second term as Director of the Institute, is widely known as petroleum geologist, gentleman, and scholar. Born in Brandenburg, Ky., he was early endowed with a Southern accent which has remained with him strongly flavored by his later life in the oil-fields of Texas and the Mid-Continent region, and only thinly concealed by a Middle Western burr acquired during his student days at the University of Chicago. After graduating there with the Ph. B. in 1908, young Wrather (the adjective still fits!) joined the Gulf Production Co. Soon afterwards he married a charming Chicago girl, Alice Dolling, who, with their two daughters, has been his companion on many of his more distant trios.

Jan 1, 1945

By M. R. Tek, K. H. Coats, D. L. Katz

The performance of a gas reservoir su,bject to water drive is often affected by interference due to gas procluction or injection in neighboring reservoirs adjacent to a common aquifer. Field data available on production-pressure behavior of several reservoirs indicate that prediction of reservoir performence must include the effects due to mutual interference. A method developed to predict the performance of two or more interfering gas reservoirs, subject to specified production-iniection .rchedule.s, is presented. The method involves the comhinatiorz of the theory of unsteady-state water movernent with appropriate meterial balance consideration.s. The procedure which extends M. Mortada's treatment for interfering oil reservoirs makes use of his dimen-.sionless pressure drop quantities. prevented graphically in the literature. In order to evaluale the predictive accuracy and practical field applicability of the theory, the method has been applied to analyze the performance of two actual gas reservoirs in mutual interference. The calculations were performed on an IBA4 704 computer. The predicted performances were alro calcltlated with the interference effects ignored. The results show that considerably better agreement between calculated and observed behavior ic. obtained when the interference effects are included. INTRODUCTION Fluid communication between any number of oil or gas reservoirs adjacent to a common aquifer results in mutual interference effects on their production-pressure behavior. The theory, application and interpretation of pressure build-up behavior of oil wells, drawdown tests on oil or gas-producing formations and behavior of several storage reservoirs indicate ample experimental evidence of mutual interference. A method developed to compute the behavior of interfering oil reservoirs was published several years ago by Mortada.4 Studies conducted during the recent years on underground storage of natural gas clearly indicated the need for extending Mortada's work to the case of interfering gas reservoirs. The adoption of appropriate material balance equations in conjunction with the unsteady-state pressure interference theory yields pressure-explicit equations. Their solution, their application to a specific case history and an over-all evaluation of the developed method through the comparison of predicted and observed field performances were the main objectives of this study. DEVELOPMENT OF MATHEMATICAL RELATIONS The diffusivity Eq. 1 governs planar, radial, unsteady-state compressible liquid flow through a porous medium. ?p/?r2+1/r ?p/?r=µFc/k ?p/?t (1) The 1iterature1,2,3 contains derivations and solutions of

Sixteen executives, technicians and operative personnel from the French mining industry, now touring mining operations in the U.S., will wind up their visit to this country at the AIME Annual Meeting. Traveling under ECA auspices, they will be in Denver on Feb. 5, Salt Lake City, Feb. 8 to 13, Bonne Terre on Feb. 16. Four of the group are engaged in bauxite mining, nine in lead and zinc, two in pyrites mining. All are interested in American mining equipment and methods, and hope to contact manufacturers' representatives in the various areas they visit. A $600,000 manganese pilot plant is expected to be put into operation by Sept. 1, by the Bureau of Mines at Boulder City, Nev. S. R. Zimmerly, chief of the Bureau's metallurgical div. for the region, recently completed the mill design and flow sheet; and the Bureau is awaiting steel priorities before building. Ore from the Artillery Peak area, 60 miles south-west of Kingman, Ariz., will be used in the mill. Construction will be handled by Rex Lloyd of Boulder City.

Jan 2, 1951

By John V. Beall

Let's start at the beginning, Mr. Turner. Where and when were you born? In Lansing, Mich., on July 31, 1880. And what was your education? I went to the University of Michigan, where I got an A.B. degree in 1902; then to the Michigan College of Mines at Houghton, graduating from there in 1904 with a B.S. and an E.M. What was your first job in the mining industry, Mr. Turner, and what were you paid? In the summer of 1902, 1 was a field assistant for the U. S. Geological Survey in southwestern Idaho and southeastern Oregon, working under Israel C. Russell, professor of geology at the University of Michigan, who incidentally, had just returned from an expedition to study the effects of the eruption of Mt. Pelee, on Martinique. I was paid $60 a month and found; in addition to doing geologic and hydrographic work, I cooked many of the meals for a party of four, and wrangled four horses. I slept for four months under the stars, without a tent.

Jan 1, 1949

By J. Groyecki, M. Markuszewicz, J. Lassota, A. Zawada

The ratio of stable to unstable inclusions was found to ploy an essential role in the process of sccorldar-y recrystatlizalion in Si-Fe. The analysis of the free energy of inclusions in the range of heat-treatment of individual inclusions to be predicted. The effects MnS. ns inslable inclusions. were investigated. TO secure a high induction, the secondary recryslulliztt-lion associated wilh the texture is necessary. To obtain a low core loss an additional refiuing in the solid state is required. It has been found that sulfur can be more easily removed in racunm than in hydrogen and thai this process was hindered by the prescrzce of INCLUSIONS play an essential role in the development of cube-on-edge texture in Si-Fe. Their function consists in restraining the growth of primary grains up to about 900°C and in passing subsequently into solution at higher temperatures. This process is accompanied by the selective growth of secondary grains with (110)[001] orientation. The general effect of inclusions depends on such factors as the type of impurities, their amount. dispersion and stability, the conditions of diffusion in the space of lattice of metal, and the reactions at the metal/gas interface. In recent years, some of these factors were the subject of a special investigation. A positive influence of Mns, siN,' and vN3 has been established. The quantity of impurities4 and their dispersion5 have been found to be of major importance. Attention was called to the vital importance of diffusion and the conditions under which the impurities are removed from metal., It has also been demonstrated that in Fe-Si alloys by the techniques of powder metallurgy a special opportunity exists to obtain the (110)[001] type texture. 6 The aim of this work was to conduct qualitative investigations on the influence of inclusion stability on the development of cube-on-edge texture in a metal containing approximately 3 pct Si. Experiments were carried out on cast alloys and on those manufactured by powder-metallurgy techniques. The results obtained from these experiments were utilized to explain the phenomena involved and to analyze the relationships between stable and unstable inclusions and the magnetic properties of alloys. EXPERIMENTS AND RESULTS The raw materials used in these experiments were the powder of carbonyl iron with the analysis (in pct) 0.044 C, 0.01 Mn, 0.005 Si, 0.009 P, 0.002 S, traces of Cu, 0.06 Ni, 0.0015 Al, 0.03 Cr, 0.02 Mo, 0.01 Ti, 0.002 Co, traces of Pb, and the powder of silicon containing 94.14 Si, 0.003 S, 0.048 C. The powders were ground and mechanically mixed in 100-g batches. and then pressed at 9 tons per sq cm into 74 by 24 by 8 mm blocks. Sintering was carried out at 1100°C for 12 hr in vacuum (2 x lo-' Tr) or in hydrogen. In this instance the material was heated slowly and subjected to prolonged soaking at 350°, 650°, and 750 2C, respectively, to secure reduction of ferro-oxides. This was checked by making measurements of the dew point, which was found to change from -15" to -35°C after reduction. The compacts after sintering were hot-rolled to 2.4 mm, annealed at 800 C, and finally cold-reduced to 0.35 mm with intermediate annealing at 800°C at a gage of about 0.8 mm. Impurities were added in the powdered form and mixed with iron and silicon powders. Sulfur in the elemental state, electrolytic manganese, and pure aluminum oxide were employed. Besides, to obtain a material with low contents of impurities, especially

Jan 1, 1967

By J. C. Bradley

THE relation of annealing temperature to conductivity of copper wire has been determined. Conductivity hard was 98.26 per cent. After a 10-min. heating at 200°C. it was 98.69. By annealing 10 min. at 300° C. a large increase, to 100.93, occurred. Maximum conductivity, 101.15, was attained after a 500° C. anneal; thereafter it decreased to 100.53 after a 950° C. anneal. If copper is gassed the decrease is much more than this. Materials and Methods The work was done on high grade electrolytic copper, 99.942 per cent. copper plus silver, silver 0.0008 per cent. It was hot-rolled to >/4 in., then cold drawn to 0.080 in. The wire was cut into 25 5-ft. lengths and numbered 1 to 25 as cut. Four samples were tested hard. The others were wound into 5-in. diameter coils. For the 100° C. heating a coil was put into water, the water brought to boiling, and the wire kept at this temperature for 10 min. For the higher temperatures the coils were placed in envelopes of sheet copper, a little water added, and the envelopes sealed by folding over the edges twice, and hammering them together. This kept the air out very well. The envelope and wire 'were brought to the desired temperature; this was maintained for 10 min., then the whole was water-quenched.

Jan 1, 1927

By Richard Akerman, Frederick Prime Jr

[THE attention now being paid both in this country and Europe the greatest economy in the working of the blast furnace, and the eagerness with which all thoughtful men in the iron business look for any new information which will tend to throw light on this subject, is a quite sufficient excuse for presenting this paper to the American Institute of Mining Engineers.] I. It must be borne in mind that when two bodies unite to form a chemical compound, heat is almost always evolved. In order to

"WELFARE…Welfare endeavor in connection with both the metal and the coal mines of Utah has shown gratifying progress during recent years and both the operators and their employees are deserving of much credit for the efforts put forth to better living, working, educational and receational conditions in most of the mining camps of the state.In the older metal mining camps of Utah, where the towns are incorporated and independent of the mining properties operating in the vicinity, less opportunity is pre¬sented for the companies to exercise efforts looking towards improved welfare conditions than is the case of camps located on company ground and under the full control of operators.Even in such camps, however, as illustrated in Bingham, the companies can do much to better welfare conditions. In this camp the Utah Copper Company has spent $800,000 since 1 920 in the erection of modern brick cottages, apartment houses and the Gemmell Memorial Club. The cottages and apartments have every convenience to be found in up-to-date city homes. The Gemmell Memorial Club, erected and equipped at a cost of $1 75,000, was provided by the company for the benefit of the Utah Copper Company employees living in the canyon and has been made the recreational center for the camp."

Jan 1, 1925

By Richard Akerman

(Translated by FREDERICK PRIME, JR., Professor of Metallurgy in Lafayette College, Easton, Pa.) [THE attention now being paid both in this country and Europe to the greatest economy in the working of the blast furnace, and the eagerness with which all thoughtful men in the iron business look for any new information which will tend to throw light on this sub¬ject, is a quite sufficient excuse for presenting this paper to the Amer¬ican Institute of Mining Engineers.] I. It must be borne in mind that when two bodies unite to form a chemical compound, heat is almost always evolved. In order to

Jan 1, 1873

By Scott Turner

HOSTS of friends will rejoice that T. A. Rickard has been given honorary membership in the Institute. It might well have been done long ago, since, when one reviews distinguished services rendered by individuals to our organization and our profession, it is at once apparent that his name ranks high and that he has merited this distinction for more than three decades. Our by-laws restrict this list to twenty names; "T.A." becomes the sixteenth living member. Young engineers should particularly be pleased; Mr. Rickard has had a career rich in human interest, and full of useful suggestions to the younger men; he has given them good advice and set them a notable example; he, more than anyone else, has shown them how technical writing can be clear and concise; he has inspired youngsters to do their best; he has been their friend. No one has more first-hand knowledge of these facts than the writer of this appreciation:

Jan 1, 1935

By J. H. East, E. R. Maize

INTRODUCTION PROBABLY no other type of equipment is now being introduced into American underground mines about which less is known and about which there is more misinformation than the Diesel mine locomotive. Any equipment installed underground brings with it hazards that were not present before, and it is the purpose of this paper to show that Diesel-powered equipment can be used with safety in underground mining if certain feasible but very important precautions are taken. Diesel locomotives are not new in underground mining, since they have been used successfully in European mines for at least 19 years, but their use in American mines is exceedingly limited; so far as is known, only five Diesel mine locomotives are operating at present in United States mines. Diesel locomotives were permitted underground in Great Britain for the first time in 1939, and the rapid increase in the number in use in those mines, testifies to their safety and efficiency. More than 1300 Diesel mine locomotives are in use in European mines, according to the latest statistics; these locomotives are employed in coal, iron, lead-zinc and mercury mines. So far as is known, the Diesel mine locomotive has not yet caused an explosion or mine fire, and has not been the cause of any fatalities from toxic gases in the mines in which it has been used. ADJUSTMENTS OF DIESEL ENGINES FOR UNDERGROUND USE A Diesel engine adjusted to work in an underground mine should not be confused with the same engine adjusted for use outside the mine. Adjustment of the air:fuel ratio for engines that are used on the surface is intended to give the maximum fuel economy, and little or no attention is given to the chemical composition of the exhaust gas produced. Many such engines are poorly adjusted and perhaps poorly maintained, with the result that the engine emits smoke in quantity as well as the disagreeable odor familiarly associated with Diesel engines. The air:fuel ratio in the case of Diesel engines operated on the surface is generally around 15:1; that is, 15 lb of air to burn 1 lb of fuel. Diesel engines adjusted to work underground usually have an air:fuel ratio of about 20:I, as at this ratio the minimum quantity of toxic gases is given off in the engine exhaust. Diesel engines operated underground must be maintained in better condition than similar engines used on the surface; otherwise, the smoke emitted in the exhaust becomes objectionable if not unendurable. Practically normal air is required for safe operation of Diesel engines underground or in confined places; failure to provide virtually normal air for Diesel engine operation is almost certain to result in trouble. Bureau of Mines engineers have determined that the air in which a Diesel operates in confined places should contain less than 1/2 pct of carbon dioxide and at least 20 pct of

Jan 1, 1947

By David T. Day

IN 1897 I published a proposed explanation t for the variation in color and specific gravity of Pennsylvania oils. A resume of this subject was also presented at the First International Petroleum Congress, in Paris, in 1900. Since that time much experimental work bearing upon this explanation has been carried on by myself, in the United States Geological Survey, and under my direction, by Dr. J. Elliott Gilpin, Marshall P. Cram, and 0. E. Bransky, at the Johns Hopkins University. The experimental results thus accumulated seem to throw considerable additional light upon the variations in color and specific gravity of petroleum, as found in different parts of the world, and also upon the variations in chemical composition. Therefore, it seems as if a, summary of the evidence thus obtained might be of value to those members of the Institute who are interested in the examination of oil-fields. The summary is here presented for that purpose. The phenomenon has often been observed in many oil-fields that oils of different color, specific gravity, and chemical composition may be found within short distances of each other. A conspicuous example of this is the occurrence at Jennings, Welsh, and Anse la Butte, La., of petroleum chemically somewhat similar to Russian petroleum; that is, characterized by the presence of naphthenes. Another characteristic is the presence of considerable percentages of asphaltic compounds, sufficient in quantity to disguise the presence of solid paraffin wax, and perhaps also to render that paraffin wax more soluble * Published by permission of the Director of the United States Geological Survey. 1 Proceedings of the American Philosophical Society of Philadelphia, vol. xxxvi., No. 154, pp. 112 to 115 (January, 1897).

Jun 1, 1910

MARCH 15-Industry is rapidly snapping back from another coal crisis, other business news is in general favorable and the outlook through the Spring is by most observers considered quite promising. Most industries report comfortable backlogs of unfilled orders, department store sales in recent weeks have equalled in dollars those of the corresponding period last year, retail sales of automobiles show again over the same period a year ago, and new orders for machine tools are at the highest figures since August 1946. Orders for railway freight cars have shown a very encouraging pickup, with a total of 9385 cars in January and the N. Y. Central alone ordering 4500 in February. Construction continues very active. In January new housing starts totaled 80,000 against 50,000 a year ago and the daily average contract awards, according to the Dodge reports, were 57 pct larger. In the first 22 days of February the increase in awards was 27 pct. Lumber orders since Jan. 1 have run 22 pct above last year. All of these favorable factors bolster the opinion that the upturn in industrial output and employment which began last summer has not yet spent itself and that the setback caused by the strikes will be made up when people get back to work. Only in a few lines are there indications that primary production may be outrunning the consumption of finished goods, although inventory build-up would seem to be rather modest as the National Association of Purchasing Agents reported in February that 78 pct of its members were buying for 60 days or less. Industrial prices as a whole show no significant trend despite the continued alarm over both the immediate and the long-term possibility of inflation caused primarily by the government's increasing expenditure and its inability to balance the budget. A recent advance of 1.9 pct in primary market prices is viewed by some people as the surface symptom of renewed inflation, but even so it is more than two years since the alltime high was reached by the daily index of sensitive commodities in November 1947. Over two years have passed since prices received by farmers hit their peak and about a year and a half since all wholesale prices and the consumer price index touched their highest points in August 1948. The decline in the wholesale price index has been almost continuous, interrupted only twice by slight advances in the monthly figures from February to March 1949, and, later in the year, from August to September. Of course, this continued decline in the last half of 1949 largely reflects a downward movement in farm and food prices. Wholesale prices for commodities other than farm and food leveled out after June and now stand only slightly under the June level. Farm products are down by 22 pct from January and by 18.6 pct from August 1948. Food prices are down only slightly less. Consequently, the farm price support program is in serious trouble and has imposed a heavy financial burden on the Treasury. In those commodities other than farm products only building materials, chemicals and textiles have come down as much as the average, while housefurnishings and metals and their products have fallen hardly at all. Glancing away from the domestic front, the results of the British general election indicated a highly inconvenient situation, that public opinion there is so exactly deadlocked as to divest the victors of much ability to make forceful decisions or create significant policy. It is generally considered that another election in the near future would give substantially the same result. The British people are equally divided and the politicians are not likely to precipitate another appeal to the country until there is manifest reason to believe that external and internal circumstances have changed sufficiently to permit one party or the other to obtain a decisive verdict. Because of the lack of a clear mandate steel nationalization will likely lag in Britain. In the meantime there is considerable discussion going on as to whether the European steel industries as a whole are at a disadvantage in world competition with the American industry. An article in the "Statistical Bulletin" for January of the British Iron and Steel Federation takes issue on this point with the authors of the Geneva report, observing that they wrote before devaluation, and this particular conclusion "has been overtaken by events." The "Bulletin" also contends that the statement was in any case incorrect so far as Britain was concerned, and that it was based on scanty and insufficient evidence. To support the rebuttal a detailed and extensive comparison is made of the home prices of certain steel products in Britain and in other countries of the world. The accompanying table gives a selection of the prices published. It sets out the changed position since devaluation and since the recent increases in American steel prices. These are home market prices; no doubt in competitive export business some of the price levels could be brought closer together at need.

Jan 4, 1950

By Harold Margolin

The Ti-Al system certainly merits the investigative attention it has been receiving and this latest contribution by Blackburn is therefore to be welcomed. The titanium-rich end of the phase diagram shown here, as well as the diagram by crossley,17 Clark et a1.,18 and Tsujimoto and Adachi,29 reveal no other intermediate phase than Ti3A1, although a previous work by Ence and Margolin20 had reported an additional intermediate phase. Since then, Buerger Precession pictures of single crystals of 10.5, 11.5, and 12.5 wt pct A1 were made at New York university21 and the extinctions were found to be typical of a D6h a Ti structure. Some superlat-tice spots and/or streaks suggesting the presence of an Mg3Cd structure, i.e., Ti3Al, were also found. Since these specimens had been quenched from the y region20 and had revealed a Ti, it was concludedz1 that y does not exist and the structures interpreted as m + y could not be so considered. The absence of normal two-phase behavior in these structures had been indicated in the paper. Accordingly, the two-phase region y + 6 becomes a + Ti3Al and there is some agreement between the results of Blackburn and of Ence and Margolin20 as to both shape and existence above 900°C of an a + Ti3Al field. Crossley 17 proposed that Ti3Al is a line compound which decomposes congruently at 900°C. It is difficult to discount entirely the fact that clear two-phase structures, varying in amount with position in the two-phase field, could be detected above 900°C by Ence and Margolin.20 Precipitation during quenching could not have been so regular and the twin-phase syndrome17 does not apply. The heat treatment and quenching technique was essentially the same as was used by Crossley, whereas Blackburn, who used a rapid quenching procedure, also showed a two-phase a + Ti3A1 field above 900°C. If the two-phase field exists above 900° C, it is easy to picture a two-phase field which could account for the data of Crossley below 900°C without invoking a line compound existence of Ti3A1. All that would be necessary would be an 0 + Ti3Al/Ti3Al boundary which curved sharply to higher aluminum contents below 900° C. It is clear that the controversy must be solved by techniques which obtain data at elevated temperatures without quenching. It is conceivable that the difference in width of the a + Ti3N fields reported by Blackburn and by Ence and Margolin is due to the longer annealing times used by the latter investigators. The criterion for establishment of equilibrium in our work20 was the

Jan 1, 1969