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By H. M. Chance

RECENT research work has shown that coal can be produced, at reasonable cost, from almost all coal-mining districts containing not more than 3 to 8 per cent. of ash. From coal so produced, an abundant supply of coke, suitable for blast-furnace operation, can be made containing from 12 down to 6 per cent. or less of ash. These statements apply broadly to the Appalachian coal belt, including most of the mining districts in Pennsylvania, Ohio, West Virginia, Kentucky, Tennessee, and Alabama. The exceptions will generally be found among those coals carrying a prohibitive percentage of sulfur. Any gravimetric heavy fluid method of separation will effect a reduction in the percentage of sulfur, but this reduction may not be sufficient to produce, from coal unfit for metallurgic use, a product that can be so used. When a large part of the sulfur is in the form known as "organic sulfur, "or is present as very .finely disseminated and homogeneously distributed pyrite, possibly it cannot be eliminated from the low-ash coal produced. When the sulfur exists as pyrite in distinct layers, bands, or nodules, or when it is finely disseminated but is irregularly distributed, often a low-ash coal low enough in sulfur to make good metallurgic coke can be produced from relatively impure coals. It has generally been assumed that the quality of coke on which blast furnaces must be operated depends on the geographic location off the furnace, and that the grade of coke on which a blast furnace must operate is that produced from the best coal obtainable by careful mining; or if the coal is prepared by washing, hand picking, or other means by which the foreign impurities are removed, that the grade of coke on which the furnace must operate depends on what has been termed the "inherent ash" of the particular coal.

Jan 6, 1924

By H. H. Stoek

Danville, the county seat of Montour county, Pa., was one of the earliest and best-known centers of the iron intlustry in the State. It is situated on the north bank of the north branch of the Sosquehanna river, twelve miles east of the confluence of the north and west branches of that river at Northurnberlttnd. The ore-belt, extending for a distance of twelve miles along the north bank, has been developed in a number of places, but nowhere so extensively as in the immediate vicinity of Danville. Hence, a description of the mines in that locality will suffice, as typical of the workings of the entire section. Geology. The Montour ridge consists of an anticlinal fold extending from the source of Wapwollopen creek on the east to the west branch of the Susquehanna, which it reaches at the mouth of Chilisquaque creek. According to the reports of the First Geological Survey of Pennsylvania, the length of the ridge is nearly twenty-seven miles, with an average breadth of three-fourths of a mile, and a maximum elevation of six hundred feet in the vicinity of Danville, where it also attains its greatest width. Just north of Danville the Mahoning creek cuts through it, exposing the iron-ore on the hill-side, where advantage has been taken of this to work the beds on the southern slope of the ridge by means of drifts. The sections given in Fig. 1 are taken from the reports of the First Geological Survey of Pennsylvania, made in 1858, by H. D Rogers, whose description of the Moatour ridge was so complete and accurate that the entire report was reprinted as an appendix to Vol. G 7 of the Second Geological Survey. The approximate crosssection shows that near Danville the top of the ridge is of Clinton vol, xx.—24

Jan 1, 1892

By R. J. Franklin, G. W. Beckman, D. Warren, E. Both, J. F. Libsch

BINARY and ternary alloys of iron, nickel and cobalt respond to annealing in a magnetic field by a characteristic change in the shape of their hysteresis 100p.l,2 An increase in retentivity and a decrease in coercive force produced by the magnetic treatment cause the hysteresis loop to approach the appearance of a rectangle. Materials with a rectangular hysteresis loop have made possible the contact-rectifier³ and have greatly improved the performance of pulse transformers4 and magnetic amplifiers." In the best material presently available for these applications, a 50 pct nickel-iron alloy," the desired characteristics are achieved by aligning the preferred crystallographic directions of magnetization along the rolling direction of the tape. The objective of the present study has been to produce rectangular hysteresis characteristics in materials with inherently high saturation. Iron-cobalt alloys, exhibiting saturation values up to 24,000 gausses' appeared to offer promise for the magnetic annealing technique, because they remain magnetic to very high temperatures,8 exhibit favorable magnetostriction properties: and show zero crystal energy at 42 pct cobalt.10 Among the ternary iron-cobalt-nickel alloys,7,11 response to heat treatment in a magnetic field is unfortunately limited to alloys having rather low saturation values.' It appeared interesting nevertheless, to study a series of compositions connecting the optimum composition (50/50) of the binary iron-cobalt system with the "Perminvar" composition (30 pct Fe, 25 pct Co, and 45 pct Ni). Very recently, R. Smoluchowski and R. W. Turner," have shown that under certain circumstances magnetic annealing can produce oriented recrystallization. A combination of this technique with the domain orientation utilized in the present study might well result in further improvements. The advantages of the powder metallurgy technique in preparing magnetic alloys for study have

Jan 1, 1951

By E. Buehler, R. H. Willens

A Hew melting technique has hem adapted to the rapid quenching of- alloys from the liquid state. The inelting method has no limitations on the alloys investigated for there is no reaction with crucible materials and the most refractory materials are easily melted. The vate of heating is so rapid that alloys which have a high vapor pressure constituent can be melted with a minimal loss in material. Several new superconductovs have been discoveved by vapid quenching of lolten alloys. THE rapid quenching of alloys from the liquid state has led to the discovery of many new metastable phases. The methods initially used were limited to alloys which did not react with crucible materials.1,2 There was also the unmentioned limitation in tem- perature. Alloys with melting points much greater than 2000°C could not be melted in the rapid-quench apparatus. Recently, there have been successful attempts to rapidly quench reactive alloys by Moss et at. and Matthias Moss et al. injected powdered material (325 mesh) into a high-temperature plasma and the high-velocity molten droplets impinged on a cooled copper plate. The technique innovated by Matthias was to melt the alloy in an arc furnace and splatter it against a copper plate by means of a high-velocity gas jet aimed at the melt. I) FAST COOLING APPARATUS The creation of a metastable phase in a given alloy system by rapid cooling from the melt is contingent on the quenching rate. Some alloys require very slow rates while other alloys require the ultimate in quenching rate. At the present time, the vertical-gun technique of Duwez and willens' has demonstrated, in practice, the highest quenching rates and thus the best

Jan 1, 1967

OPEN-HEARTH refractories are not merely an accessory to the furnace. They are the furnace, to all intents and purposes. The steel work of the main structure is merely an open frame which helps to support the refractories ; and the regenerators, a necessary part of the furnace system, consist almost entirely of refractories. Not only do refractories constitute the essential part of the furnace, but they also carry the liquid steel all the way to the point where it begins to solidify. On leaving the furnace the liquid passes through a refractory runner into a refractory-lined ladle, then through a refractory nozzle closed by a refractory stopper on the end of a rod protected by refractory sleeve bricks. The liquid is sometimes sent through an additional refractory- lined tundish, a supplementary ladle, or a refractory runner for bottom pouring, until it finally enters the iron mold in which it solidifies. Even in the mold, refractory materials are sometimes used to provide a nonconducting "hot top." This series, from runner and ladle to hot top, inclusive, is often referred to collectively as the "pouring-pit refractories." REFRACTORY RAW MATERIALS The raw materials available are best classified into basic and acid types. The principal basic raw materials are magnesite, dolomite, and chrome ore. The principal acid materials are silica in various natural forms, and fireclay. Magnesite. Austria was the principal source of magnesite (MgCO3) until recent years, when the Province of Quebec, in Canada, and the states of Nevada and Washington became important sources for the American steel industry. More recently these natural sources have been supplemented by the so-called "sea-water magnesite"-which is the name somewhat incorrectly given to magnesium hydroxide obtained as one of the products

Jan 1, 1964

C. W. GOODALE, Butte, Mont. (member of the committee)- (communication to the Secretary*).-In the discussion of papers presented at the New York meeting of the Institute in February, 1915, and at the Arizona meeting of September, 1916, I referred to the activities of the Bureau of Safety of the Anaconda Copper Mining Co., and I am now submitting a few thoughts by members of the staff of that Bureau. TORGUS H. OAAS, Safety Engineer, Butte, Mont.-The report of the Committee on Safety and Sanitation has described different organizations and methods of promoting safety work. The effectiveness of these methods would aid the beginner in his campaign for safety in choosing the kind of organization and methods best adapted for his field. This can he obtained only by a discussion by those who have long promoted this kind of work, and have met with successful results. As the field is new, the different organizations promoting safety work have not established a common basis of rating for their fatal, serious and slight accidents, so that it is now difficult to get a comparative basis from which to judge the merits of the different systems. C. W. GOODALE.-The U. S. Bureau of Mines adopted, at the beginning, as a basis for its yearly summaries, the number of accidents. per 1,000 men employed, and it is now (quoting from its report for 1915, Technical Paper 168) making the following "classification of injuries:" "Many of the States now have. compensation laws, and in order to conform with their classifications, the bureau's classification of serious and slight injuries for 1915 is on a 14-day (2-week) basis instead of 20 days, as in previous years. The new classification of injuries includes three types, as follows: 1. Fatal 2. Serious (time lost, more than 14 days) (a) Permanent disability Total Partial

Jan 6, 1917

By William R. Webster

The unusual interest taken in the papers on steel at the New York (1922) meeting showed that the time is ripe for the renewal of the general discussion of the physics of steel, on the same lines that wete used formerly and produced such good and lasting results. The curves shown in Figs. 1 to 4 and the appendix were added to my paper1 after the February meeting, but, unfortunately, Figs. 1 and 3 were transposed; the curves on page 252 are for bessemer steel and belong on page 254; while those on page 254 are for open-hearth steel and belong on page 252. These errors are evident at once on referring to the data in Tables 1 and 2, pages 227 and 228. The curves for each 0.05 per cent. of carbon and manganese in basic open-hearth steel are given in Figs. 1 and 2; these lines for the lower carbons and manganese are comparatively uniform. Figs. 3 and 4 give similar lines for carbon and manganese in bessemer steel. The large break in the carbon lines from 0.55 per cent. to 0.60 per cent. is caused by much higher silicon in the steels of 0.60 per cent, carbon and over that are used for springs, etc. The estimated ultimate strength of pure iron, and the increase in strength by carbon, phosphorus, and manganese, with the different views regarding the same, were given and diseussed. All of this can be considered as an introduction to the practical use that is now being made of such data in selecting the heats of steel best suited to give the required physical tests called for in the finished rolled material. The chemical composition of the steel, of course, tells only a part of the story, as many other factors that have an influence on the physical properties of the steel must be considered, and controlled as far as is possible. Some of these have already been referred to, but there are other important ones to be considered and discussed.

Jan 1, 1923

By William Kent

Mr. ASHBURNER's paper on the Classification and Composition of Pennsylvania Anthracites, read at this meeting, well shows the need of new and accurate determinations of the heating value of these coals. A similar need exists for the determination of the value of bituminous coals, since the variation in quality of the latter is greater than the variation in anthracites. The recent extensive use of liquid and gaseous fuels, " patent" fuels, tan-bark, and other refuse fuels, also makes a necessity fix some correct method of determining the relative values of each of these fuels. Mr. Ashburner has recommended that tests of coals should be undertaken by the Second Geological Survey of Pennsylvania, and Professor Dewey, as stated in Mr. Ashbnrner's paper, has suggested a plan for tests of American coals, by the Smithsonian Institution, for which an appropriation by Congress will be asked. It is to be hoped that if any extensive series of tests of coals is carried on under either Government or State auspices, the erroneous methods of test which were followed by Professor Johnson in 1842, and by Quartermaster-General Meigs in 1882, will not be adopted.* The first requisite in determining the heating-power of a fuel is proper apparatus, such as has not been used in any of the tests of American coals yet reported. In the hope that more accurate means may be used in future tests, the writer desires to call attention to an apparatus which he has designed for the purpose. Not having had opportunity for making a trial of it, nor even of having it criticised by others, he does not offer it as the best possible apparatus; but if it contains any points of value, and leads to the design of still more suitable devices by others, the object of the presentation of this paper will be accomplished. The tests by Professor Johnson and General Meigs were made by evaporating water into steam in ordinary steam-boilers. A steamboiler of ordinary construction is not a good apparatus for determining the heating power of a fuel, for the following reasons:

Jan 1, 1886

By B. F. Buie

For over 200 years meerschaum has been a significant item of trade between the Near East and countries to the west. Best-known for its use in making smoking pipes and cigar and cigarette holders, it is also used in making a variety of decorative and ornamental items. It is easily carved, and is given an attractive, lustrous finish by rubbing. No published specifications are known, but compact form, purity, uniform whiteness or light color, and uniform, porous texture appear to be requisites. Fig. la shows the appearance of a piece of crude meerschaum from Turkey; [Fig. lb a carved item; and Fig. lc, d, and e] show the fibrous and porous texture as revealed by the scanning electron microscope. Neither a major industrial mineral nor a precious stone, meerschaum nevertheless holds a record of long-and continuing-association with art and personal affairs of man. It is also a mineral to which modern methods of exploration and production probably could be profitably applied. An interesting account of the preparation and use of meerschaum in the early part of this century is given by Sterrett (1907). Geology and Mining Mineralogy Meerschaum is recognized now to be the compact variety of sepiolite, the claylike variety of which is one of the minerals included in the chapter on clays. The word "meerschaum," from the German meaning "sea foam," was in earlier times used synonymously with "sepiolite," a word of Greek origin suggestive of the resemblance of the compact variety-then the only variety known-to cuttlefish bone. At one time "meerschaum" was used as the commercial name, and "sepiolite" for the scientific name. However, to think of meerschaum as the name by which sepiolite is known commercially is no longer valid, in view of the recent emergence of the earthy variety as a competitor of bentonite and other clay materials. Present tendency is to restrict the term "meerschaum" to the compact variety, and to use the term "sepiolite" as a more general name to include both the compact and earthy varieties. This is the terminology followed in this publication.

Jan 1, 1975

By William R. Webster

The unusual interest taken in the papers on steel at the New York (1922) meeting showed that the time is ripe for the renewal of the general discussion of the physics of steel, on the same lines that wete used formerly and produced such good and lasting results. The curves shown in Figs. 1 to 4 and the appendix were added to my paper1 after the February meeting, but, unfortunately, Figs. 1 and 3 were transposed; the curves on page 252 are for bessemer steel and belong on page 254; while those on page 254 are for open-hearth steel and belong on page 252. These errors are evident at once on referring to the data in Tables 1 and 2, pages 227 and 228. The curves for each 0.05 per cent. of carbon and manganese in basic open-hearth steel are given in Figs. 1 and 2; these lines for the lower carbons and manganese are comparatively uniform. Figs. 3 and 4 give similar lines for carbon and manganese in bessemer steel. The large break in the carbon lines from 0.55 per cent. to 0.60 per cent. is caused by much higher silicon in the steels of 0.60 per cent, carbon and over that are used for springs, etc. The estimated ultimate strength of pure iron, and the increase in strength by carbon, phosphorus, and manganese, with the different views regarding the same, were given and diseussed. All of this can be considered as an introduction to the practical use that is now being made of such data in selecting the heats of steel best suited to give the required physical tests called for in the finished rolled material. The chemical composition of the steel, of course, tells only a part of the story, as many other factors that have an influence on the physical properties of the steel must be considered, and controlled as far as is possible. Some of these have already been referred to, but there are other important ones to be considered and discussed.

Jan 1, 1923

By J. J. Pelley

NOT being a scientist, an engineer or a metallurgist, I consider it a very great honor indeed to be asked to address the American Institute of Mining and Metallurgical Engineers. Your program indicates that any lack of intricate and technical knowledge on my part in the field of metals will be well taken care of by others. Therefore, I believe any remarks that I have to make might well be devoted to the practical side of metals in railroad service and to the general railroad situation as I view it today. The experiments now being conducted on the railroads with so-called streamlined, light-weight trains and cars would not have been possible had it not been for scientific and engineering research in the past that made these lighter weight metals available. The railroads now have approximately forty units of these new trains in operation. Experi-ence with them will no doubt be a guidepost for future construction in that direction. While the best known experiments are in the passenger service, they are being extended into the freight service. Within the past three years there was constructed for the Association of American Railroads a new standard box car of ordinary carbon steel, in which, by reason of superior design, weight was reduced by 3500 to 4500 lb. under that of existing cars of like capacity. The Association is now testing a box car that weighs approximately six or seven tons less than practically all of the box cars of like capacity in service today. If these tests are successful a very large field for the use of lighter weight metals will immediately be opened, provided the costs of such metals are not too high. The fact that various experiments are being carried on with other classes of equipment constructed with so-called light-weight and non-corrosive metals no doubt will have a considerable effect upon the rebuild-ing of old equipment. The question then will be: How much can we afford to spend on the rebuilding of an old car weighing six to seven tons more than a new car constructed with the latest available materials?

Jan 1, 1936

By A. M. Guadin

Direct quantitative comparison of the results of concentrating operations on different ores is frequently desired but almost impossible to obtain if comparison has to be made by means of two quantities for each ore, as must be done at present. This paper represents the outgrowth of attempts to arrive at a single-number quantitative measure of the segregation between minerals or metals as the result of concentrating operations. The usual practice in estimating the effectiveness of concentrating operations, particularly those of ore dressing, has been to determine the recovery of the metal or mineral of interest and the grade of the concentrate. The difficulty in quantifying the effectiveness of concentration by the usual criteria may be illustrated by a few examples. Consider, for instance, two lead ores which yield by flotation the same recovery of lead, say 92 per cent., and the same grade of concentrate, say 60 per cent. Pb. If a substantial difference in the grade of the feed had existed, say if one ore contained 5 per cent. Pb and the other 10 per cent., it is clear that the concentrating operation was more effective in the case of the lower grade ore. It is difficult, however, in the light of these data to state how much more effective was the concentration of the lower grade ore. Consider again two lead ores containing 5 and 10 per cent. Pb and yielding concentrates containing 60 and 72 per cent. Pb respectively, with recoveries of 93 and 92 per cent. respectively; it is well-nigh impossiblc to tell from these figures which results represent the best separation of the minerals. It may be noted that in the usual method of estimating the effectiveness of the segregation of mineral values, no consideration is given to the rejection of the unwanted substances from the concentrate, except in the very indirect manner in which it enters into the grade of the concentrate. Consideration of the rejection of gangue from the concentrate, adequately weighted with recovery of the desired mineral in the concentrate, should supply an adequate criterion of concentration effectiveness.

Jan 1, 1930

By Thomas Read

READJUSTMENT Of the industrial world to a peace .basis after more than 4 years of war will involve many fundamental and far-reaching changes that cannot as yet he clearly foreseen or definitely provided for. Such problems may be subdivided, in the vocabulary of war, into those involving material and those centering about personnel. Of the two, the-latter group is the more difficult and obscure, as the factors involved are less clearly understood and the methods to be followed are not yet tested and standardized. When it is said that the market is weak, stocks large, and demand light, every business man understands clearly what is meant and. what course he should adopt to adjust himself, so far as possible, to such conditions. But when it is said that the rapid spread of Bolshevism in Europe is a danger to industrial organization in this country, it is difficult to have any assured sense that all that the statement may mean is clearly understood or that the means to be followed to meet such a situation are definitely known. Since Bolshevism is primarily a mental phenomenon and since the rupture it brings about in industrial organization should be prevented, if possible, it is my purpose to restrict this discussion of the activities of the Committee on Industrial Organization to some of its mental aspects, as the chairmen of the sub-committees, from their special knowledge of their own fields, can best set forth recent progress in the lines with which they are especially concerned. The first requisites of success in industrial organization, as in the biological organism of which it is the social counterpart, are unity of purpose and coordinated activity. Typical good and bad examples of this are the relative parts that the United States and Russia have played in the great war. These two factors are primarily mental, and it is not difficult to view the mental aspects of all problems of industrial organization as the most important ones. Unless we can attain unity of purpose and coordinated activity in industry, the provision of comfortable homes at reasonable rent, the assurance of steady work at good wages, the

Jan 2, 1919

By Stanley Herold

A FEW notes on the occurrence and significance of mud volcanoes in Colombia may be of interest at the present time, owing to the renewed activity in geological exploration of, the coastal regions bordering the Caribbean Sea. The best-known volcanoes are found a few miles from the seacoast. One is situated to the south of Puerto Colombia; the second, to the east: of Cartagena near the village of Turbaco; and the third, near the village of Puerto Escondido south of the Sinu River. Others. are reported in more inaccessible localities. Usually they stand 2 1/2 or 3 ft. (0.762 or 0.914 m.) above the surrounding ground at the crater, though several craters from 10 to 20 ft. (3.04 to 6.09 m.,) apart will often build up an extensive mound at low gradient. The shallow mound may cover 1/2 or 3/4 acre (0.2 to 0.3 ha.) with an elevation of 12 or 15 ft. (3.65 or 4.57 m.) at the center. The craters are formed of hardened blue clay; the inside diameters vary from 14 to 24 in. (35.56 to 60.96 cm.). The rim is continuous, except on one side where there is usually a cut 3 or 4 in. deep, thus allowing an overflow. The craters are filled to the rim-cut- with a thick mixture of blue clay mud and water, which is kept in agitation by escaping gas. Fig. 1 shows the bubble in the act of bursting and Fig. 2 the appearance of the surface of the viscous fluid a second or so later. The frequency of the explosions is determined by the weight of the column of fluid in the neck of the volcano, consequently, such explosions are not synchronous in a group of craters. Ordinarily, there are two or three explosions in about 3' minutes. The supply of gas is small but steady and sufficient pressure must accumulate before the bubble can enter the column of fluid. The water is derived from the surface and enters the sedimentary strata not` far distant from the volcano. During long dry seasons, as the supply of water fails the volcano dries and geyser action ceases.

Jan 7, 1919

By Charles Schwab

WHEN I leave this life, as an employer of labor there is no one thing that I want so much to be engraven upon my monument as the fact that I have been one of the men who have worked, whether with my brains or my hands, for the advance-ment of industry in the United States, and to be regarded, as I should like to be regarded by labor with love and kindly remembrance for our years of association. In my relationship with my employees, I have always contended that every man should be paid for what he does. I will not employ or be associated with any kind of labor of which the organization insists that a man shall receive a fixed sum of money for his day's wages, however poor or good his day's labor may be. What applies to the common laborer applies equally well to the management, the brains of an industrial establishment. I have always thought of industry as a three-legged stool, with capital, management and labor as the legs. All three legs of that stool must be there before that stool can stand up. If you take any one of those legs away, it is going to topple over. The. three must stand together for successful business accomplishment. I believe that a man who has his labor to sell, to put it plainly, has just as good a right to bargain for the best price for that labor as those who employ him. It is a perfect right for him to do so. If the government of our United States is right, our method of handling labor in our Bethlehem plants is right because it is representative and democratic. We have our labor elect delegates; elect representa-tives from their own ranks, who shall meet frequently. That constitutes, as. it were, the House of our great Congress in Washington, the industrial house. We have our management, who represent the Senate, who meet independently. Working men have learned to express their views freely as to whether they are treated fairly and whether conditions are right or wrong.

Jan 12, 1922

By E. P. Klier, Volker Weiss, George Sachs

IT has been shown that the isothermal transformation of austenite in a special steel can be modified by isothermal holding in the high subcritical transformation range.' Since this treatment potentially leads to increased hardenability, limited testing has been completed to determine if the stabilization effects observed with this treatment can be used to advantage in the heat-treating of 4340 steel. As an index of the effects of the several austenitizing treatments on the hardenability of the steel, Jominy-type hardenability tests were completed for specimens 2.5 in. in diameter and 8 in. long. Since the steel studied is to be used at strength levels where notch sensitivity is of major concern, notch sensitivity after selected austenitizing treatments has been evaluated by notch tensile tests for several specimen sizes. The steel composition and the austenitizing treatments are given in Table I. The test specimens are presented in Fig. 1. The hardenability data are given in Fig. 2 and the notch tensile properties are presented in Fig. 3. The hardenability of the steel investigated when determined by use of the standard Jominy test specimen2 as high and remained essentially unchanged for the different austenitizing treatments. For the larger test specimen, as has been shown by other investigations," the characteristic hardenability indexes are changed and it becomes possible to isolate austenitizing treatments which promote maximum hardenability. The stepped austenitizing treatment promotes higher hardenability as is indicated in Fig. 2. The evaluation of notch sensitivity for very high strength steels is best accomplished by means of the notch tensile test. The experimental conditions of the test, however, modify the notch strengths measured, and in the present experimentation an effort was made to achieve a limiting notch condition by fixing the notch root radius at 0.001 in. while the specimen diameter was allowed to increase from 0.3 to 1.1 in.* For this root radius the notch strength, 0.3-in.-diam specimen, and this trend differs from that for the larger specimens. At the highest tempering temperatures the 1.1-ip.-diam specimens yield comparable results for the austenitizing treatments compared. However, as the tempering temperature is progressively lowered below 800°F, em-

Jan 1, 1958

By Byron Bird

WHILE Mr. Fahrenwald has been working on the fundamentals of ore-dressing, in Idaho, the Northwest Experiment Station of the U. S. Bureau of Mines, in cooperation with the University of Washington, has been studying the corresponding fundamentals for the closely-allied subject of coal-washing. In this work many of the principles outlined in Mr. Fahrenwald's paper have been touched on, one important exception being that phase of his studies where conditions were approximated between those existing on a table and those existing in a hindered-settling classifier. During the past three years this work has been given over almost exclusively to a study of coal-tabling to devise better methods of cleaning fine sizes of coal, particularly the coals of the Northwest, which are very difficult to wash. One important result of this study thus far has been the development of a satisfactory hindered-settling coal classifier, now in use in several commercial plants. Recently table stratifica-tion has been the subject for study. This latter phase of the work with coal,. as well as the earlier portion dealing with hindered-settling classification, has in a measure paralleled Mr. Fahrenwald's work with ore. Without going into details about the results of the coal experiments, I shall merely say that, from a quali-tative standpoint, they are, in general, concordant with Mr. Fahrenwald's, but that from a quantitative stand-point the results, particularly those with, table strati-fication, are somewhat different. These differences may disappear as the work progresses-Mr. Fahrenwald is further ahead with his experiments than we are at the Northwest Station-but if not, the disparity would not be surprising, and indeed would be what one might reasonably expect when investigators work on two very dissimilar materials and use different apparatus and methods of study. However, this- mention of our coal-washing experiments is made only in passing. A principle of general application that may be estab-lished from Mr. Fahrenwald's paper is that different types of stratification should be used in successive' gravity-concentration processes to. obtain best results.

Jan 3, 1927

The Committee on Nominations begs to submit the following names as its nominees for the respective offices indicated: For President, SIDNEY J. JENNINGS, New York. For Vice-Presidents. C. W. GOODALE,* Butte, Mont.; MARK, L. REQUA, San Francisco. For Directors, J. E. JOHNSON, JR., New York; ALLEN H. ROGERS, Boston; HOWARD N. EAVENSON, West Virginia; ROBERT AI. RAYMOND, New York; WILLET G. MILLER, Canada. The nomination for President has attracted the attention of a large number of members, as is evidenced by the receipt of many hundreds of letters and postcards. Most of these favored either Sidney J. Jennings or Philip N. Moore, each of whom received many cordial endorsements. Such a wide interest on the part of the members is a very wholesome sign, but where there is so much activity it is natural to expect a certain amount of criticism. Some of the letters indicate that the authors feel that the nomination of President should be left entirely to the Committee on Nominations without any effort by the members at large to influence them. Others feel that the nominations are largely controlled by a small group and that the members at large can have little influence. As the result; of the experience of the last few months; a majority of the Committee on Nominations begs leave to suggest that the method of making nominations be changed so that two candidates, at least, for the various offices to be nominated, and suggests that the Directors appoint a committee to investigate this question thoroughly with. a view to making definite recommendations. In accordance with its opinion that the best interests of the Institute would be served by a change in the Constitution, allowing the nomination of two candidates, and in view of the fact that this Committee has no authority to make more than a single nomination for each office, considering the high standing of both Mr. Jennings and Mr. Moore and the large number of members favoring each of these gentlemen, this Committee respectfully suggests the desirability of ,the immediate nomination of Philip N. Moore by a petition of 25 members in accordance with the present Constitution. This Committee regrets, its inability to make two nominations. Respectfully submitted, S. W. MUDD, Chairman.

Jan 1, 1917

By E. M. Norris

In the summer of 1917 it was decided to fireproof the main Tramway hoisting shaft of the Anaconda Copper Mining Co. at Butte, Mont. The shaft has three hoisting compartments and one pump compartment; it is timbered with 12 by 12-in. (30.5 by 30.5-cm.) fir timber, and is 2475 ft. (754 m.) deep. Subsidence and displacement of the surrounding country rock had produced exceedingly heavy ground, and had carried the shaft out of line, in several places, by as much as 2 ft. (0.6 m.) displacement. Constant repairing and realigning of the timbers had been necessary in order to maintain clearance for the cages. The most feasible method of fireproofing, therefore, seemed to be to cover the timbers with a coat of concrete applied with the cement gun. The cement gun, which is operated by compressed air at ordinary mine pressures, feeds a mixture of sand and cement through a hose to a nozzle having a water connection. The mortar in fluid form is thus sprayed upon the prepared surface in thin layers, which can be built up to any desired thickness. The cement gun can be set up at any convenient point; satisfactory results have been obtained with the nozzle a distance of 500 ft. (152 m.) from the gun. The shaft was thoroughly overhauled and the timbers put in the best possible state of repair. Between the 1000 and the 1400 levels, much loose ground lay against the shaft timbers on the north side; this was breast-boarded back and a 30-in. (76-cm.) reinforced-concrete retaining wall was erected, leaving a space of 12 in. (30.5 cm.) outside the shaft timbers to allow for future movements of the ground. For convenience in handling men and materials, it was arranged to concrete the auxiliary hoisting-cage compartment and the pump compartment first, using the cages of the main hoist to serve the cementing crews. The auxiliary cage was then available while the remainder of the shaft was being concreted. A tight partition of 2-in. (5.08-cm.) plank was erected between the auxiliary and the adjoining hoisting compartments, for better protection of men riding on the cages. The application of concrete made this

Jan 1, 1920

By Enrique Touceda

The question as to the proper amount of total carbon that the malleable founder would prefer to have in pig iron for use in the production of air-furnace, white iron castings, must be considered from different angles, that is, whether it is desirable or advantageous from an economic standpoint to use some kind of low-carbon scrap on his mixture, or make use of pig and sprue only. Whereas silicon is the acknowledged scrap carrier in the case of cupola gray iron castings, carbon performs this role for the most part in malleable iron practice, irrespective of the character of furnace used for the production of the white iron castings. In this particular, the advantage lies with the maker of gray iron castings in that the silicon content in pig iron through a regulation of furnace temperature is under very easy control by the blast-furnace manager, whereas he has little or no control over the resultant percentage of carbon, as this is dependent on the quantity of coke in the hearth, and hearth temperature, coupled with the amount of hearth slag and its particular composition. As perhaps more than 95 per cent. of white iron castings are made in air furnaces the following statements are intended to cover that situation particularly: In the malleable process the composition of the hard iron castings (that is determined upon as best suited for the work in hand) is the one factor that must control the composition of the mixture to be used; because if the elements are not between certain definite limits individually and collectively the annealed or finished product will be unsoitable, due, perhaps, to lack of sufficient strength or because it is too hard, to machine easily. The annealed product can be divided into two classes, one of which greatly predominates, that is, by far the largest tonnage is used for machine parts where high strength and ductility are essential requisites, while a far smaller amount, light in weight and thin in section, is used for other manufactured products in which castings of any reasonable degree of strength and ductility have proved satisfactory.

Jan 1, 1927