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THE strike of the coal miners began on April 1, as had been expected, the entire force of unionized miners-both anthracite and bituminous-going out and making this the most widespread strike of record. Up to the present writing there has been no serious inconvenience to industry in general, the accu-mulated stocks of coal being large and the non-union mines having continued to make a substantial production. However, the union labor leaders, having concentrated their efforts toward inducing the non-union miners to go out also, met with some measure of success in certain fields and created a shortage of coking coal, which caused iron makers to bank a few furnaces. The strike of textile workers in New England spread further. Here and there, throughout the country there were sporadic troubles with the builders. Rail-way labor was the subject of continued palavers, which did not get anywhere. On the whole the events of April were in line with the forecast that this would be a year of labor troubles. In domestic politics, the soldier bonus bill, having been passed by the House, went to committee consider-ation in the Senate. Public opposition to it manifestly waxed. On the floor of the Senate the tariff bill was under consideration and is drawing nigh to passage, without there being much consideration of its probable economic consequences. It is going to be a very high tariff and there is much in it that is equivalent to subsidizing small and normally unprofitable industries at the expense of the people as a whole. Abroad affairs were more quiet, superficially at least; than they were in March. In Egypt, India and South Africa things calmed, down, so far as we know, but in Ireland there was continued turmoil. The Irish, having won their freedom to the same degree as the Canadians, have entered upon violent quarrels among themselves, more over phrases than anything .else, so far as we can see. Lloyd George obtained a spectacular vote of confidence from Parliament and thus postponed, the exigency of a general election.

Jan 5, 1922

By Frank Alfred Fahrenwald

Discussion of the paper of FRANK ALFRED FAHRENWALD, presented at the New York meeting, February, 1916, and printed in Bulletin No. 109, January, 1916, pp. 103 to 149. F. A. FAHRENWALD, Cleveland, Ohio (communication to the Secretary*).-Since the publication of my paper in the January Bulletin, (which was largely a metallographic treatise), I have been questioned regarding two points referred to therein. One of these is that which deals with the application I have made, p. 119, of the equation for melting pressures which correspond with different working temperatures. The other refers to the statement, p. 137, that "Prolonged heating at relatively low temperatures gave fewer and larger crystals and crystals of different sizes, while a flashing at higher temperatures gave a very fine and uniform crystalline structure, which was much' to be preferred." Especial emphasis was not placed upon either of these two factors, for each seemed perfectly logical and obvious. As they do not seem to be self-explanatory, I will supplement with those portions of my notes which were purposely omitted from the manuscript submitted for publication. A few practical illustrations may serve as evidence in support of the first of these, but it must be understood that in this work the "amorphous theory" is considered as being sound, and that it is assumed that metals allow of distortion, without fracture, by virtue of the formation of slip surfaces, accompanied by the transformation of crystalline material to the, amorphous phase. Effect of Pressure.-In all forging, rolling, and drawing operations, it is known that specimens of small cross-section may be worked at a lower temperature than can be used for the same material in much greater mass and sectional area. In -the larger pieces the maximum pressure is brought to bear upon the material near the surface, so that the interior is not subjected to great pressure, but to, a stress more nearly tensile, or shearing, so only the surface is subjected to the critical melting pressure. In the case of wires which draw hollow, the center is subjected to practically a tensile stress which breaks it, while the surface skin draws perfectly, due to the enormous "flowing" pressure exerted upon it by the surface of the draw-plate.

Jan 5, 1916

AT THE beginning of November, Mussolini had firmly established himself at the head of the Italian Government. He himself referred to the ascendancy of the Fascisti as the result of a revo-lution and bluntly informed Parliament that it was to vote, as a matter of form, as he ordered, or else be dissolved. One of the great consequences of these events in Italy was the impetus that they gave to simi-lar movements in other countries of Continental Europe. Another great event of the month in world affairs was the repudiation by the Turks of the Mudania agreement and their notification to the Allies that the latter must evacuate Constantinople and allow the Dardanelles to be closed. This had the effect of once more consolidating Great Britain, France and Italy in so far as this question is concerned, and there was prompt refusal to accede to the demands of the Turks. With the advent of November, both the United States and Great Britain were in- the throes of political contests. The result of the American election was a landslide against the administration and especially was it an expression of agrarian discontent and a declara-tion in effect that our domestic affairs are not good in spite of political representations that they are. In Great Britain, the Conservatives were put in power by a substantial majority in Parliament, but the fact that the Labor party became numerically the second party instead of the Liberals and that it polled about 40 per cent. of the total popular vote affords ground for misgivings, especially when it be considered that the Labor party was standing on distinctly socialis-tic and communistic principles. In Russia, there was a sitting of the Third Interna-tionale, to which Lenin in a speech made a quasi-confession of the failure of the communistic experiment in Russia. He admitted, moreover, that Russia could not industrially reconstruct herself without capitalistic help. Nationally the country is making progress. During November, the Far Eastern Repub-lic surrendered to the Soviet, which thus carried Russia back to the shore of the Pacific.

Jan 12, 1922

By T. S. Taylor

THE development of the linear hot-wire anemometer has been chiefly clue to the efforts of L. V. Kings1 and A. E. Kennelly and H. S. Sanborn.2 The anemometers used by these investigators consisted essentially of a fine heating wire having attached leads for resistance measurements at distances of 10 or more centimeters from each other. In using such an anemometer, the current is measured that is necessary to maintain the resistance of the wire, between the two leads, constant for different air velocities. Thus resistance is always so chosen that the temperature of the heating wire will be sufficiently high to make the observations practically independent of small variations in the temperature of the gas in which the anemometer is placed. The measurement of the resistance of the anemometer wire requires a Kelvin bridge set up, which for commercial work is not altogether desirable. The cooling effect clue to different air velocities depends on the temperature difference between the wire and the gas and the total quantity or mass of gas passing the wire per unit tine. Since the temperature of the wire is maintained constant, the effect observed in the change in the heating currentfor a given change in air velocity is a measure of the difference between the gas flow in the two cases. Such an anemometer, therefore, measures the average gas flow for a length depending on the distance between the two resistance leads. Therefore the instrument in the form used thus far is not very satisfactory for measuring gas velocities in small tubes or in places where the velocity varies rapidly across the line of flow. For the purpose of measuring gas flow through relatively small tubes, where the velocity changes rather rapidly across the tube, the hot-wire anemometer has been modified in the manner shown diagrammatically in Fig. 1. It consists essentially of a platinum heating wire H about 0.007 in. (0.178 mm.) in diameter and ½ to 1 in. (12.7 to 25.4 mm.) long stretched across a suitable framework, say of glass. This wire has

Jan 9, 1919

By S. B. Flagg

Advancement in the art of burning fuels for steam generation has been so marked and so rapid in the last 10 or 15 years that one may well hesitate to classify as unsuitable for stationary steam boiler firing any material having a fuel value. This statement should not be interpreted to mean that any existing boiler plant can successfully utilize any fuel with which it might be supplied. It does mean, however, that almost without exception it is possible to design and construct stationary boiler plants so that they can be operated with whatever coal is the economic supply therefor. In considering the subject of the use classification of coals, it must be recognized, first, that the suitability or unsuitability of a coal for certain uses or conditions may be largely a matter of opinion and, second, that as advancement in the art of burning fuels continues, fuels that may have been considered unsuitable may later be regarded as entirely suitable. This is well illustrated in the creation of a market for slack bituminous coal and for the finer sizes of anthracite that resulted from the development of mechanical stokers adapted thereto. Coke breeze is another fuel of which large tonnages were formerly wasted, that has now been found suitable for use in properly designed furnaces. Again, results that would have been thought quite impossible a generation ago are being obtained in steam boiler plants today with lignites of high moisture content and with coals of excessive ash content. It must, however, be admitted that oftentimes an existing boiler plant can be successfully operated with only a limited number of the coals that are available as possible supplies. We may briefly consider some of the more important factors that may affect the suitability of coals for such a plant. Insufficient or barely sufficient draft to meet peak steam demands is often a limiting factor, and the permissible frequency of fire-cleaning periods is another. In some cases, the action of the molten coal ash on refractory furnace linings prohibits or makes inadvisable the use of certain coals. Again, clinker conditions in the fuel bed or slag conditions on the boiler-heating surface may be much worse with some coals than with

Jan 1, 1930

By C. S. Trewin

Zinc, in its wrought form, is produced commercially in rolled strip, sheet, wire, rod and tubing. Wire has been made periodically, but due to the fact that slight drafts are necessary, the cost of production is greater than for the more common non-ferrous metals which are made into wire. Notwithstanding the cost, zinc wire has certain special uses for which it is particularly adaptable. Rod has been made both by rolling and extrusion; the product, however, has not indicated great commercial value. Tubing has been made from strip from time to time by forming a strip around a mandrel and either electrically or gas-welding a longitudinal joint. Recently a tube manufacturer has succeeded in making a fair quantity of this material. Its commercial adaptability is still to be dctcrmined but anyone who desires it can obtain quantities of the smaller sizes. Inasmuch as strip and sheet are commercially the most important, this paper will be devoted to these products. In the broader sense, zinc is not alloyed. That is, there are no combinations comparable to the various copper, aluminum and nickel alloys. It has been recognized for some time that the lead and cadmium occurring with commercial zinc have some effect on its properties and such alloys as may be said to exist are those made from zincs containing varying amounts of lead and cadmium with a relatively low iron content. The foreign rolled zinc will analyze higher in lead than the domestic grades. A representative foreign analysis will run 1.1 per cent. lead, 0.07 per cent. cadmium and 0.02 per cent. iron. The American grades vary from zinc approximating high grade and analyzing 0.08 per cent, lead, 0.002 per cent. cadmium and 0.015 per cent. iron, to the lower grades in which the lead will vary from 0.3 to 1.0 per cent., cadmium from 0.10 to 0.5 per cent. and the iron in the neighborhood of 0.02 percent. Rolled Zinc Rolled zinc is produced in both the strip (or ribbon) form in which the product is rolled from a single bar in one continuous direction, or sheet in

By Walter Miller

The broad picture of petroleum refining engineering during 1934 continued to show a tendency in the direction of highly specialized processing improvements, particularly in manufacture of lubricating oil. The slowing up of the trend toward higher octane products in non-premium gasoline noticed in 1933 was definitely established as a fact by 1934 development, with just a slight indication of recession. No outstanding engineering achievements can be credited to 1934 in refinery cracking, unless the completion and successful operation of the 30,000-bbl. crude capacity combination cracking and skimming unit at Texas City, Texas, and a 20,000-bbl. similar unit in the East can be listed as such. Development and improvement was largely a continuation of previous lines of endeavor. Such trend as there is shows a continnation in the direction of very large integrated skimming and cracking units. A lessening of the cost of ethyl lead, coupled with the reaching of the octane number "ceiling," kept the subject of "reforming" low-octane gasoline into high-octane products pretty well in the background. Considerable interest, however, was shown during the year in cracking and polymerizing of refinery gases into high-octane motor fuel. The commercial development and application of this activity was greater in 1934 than during any previous year. Fair yields of gasoline of satisfactory stability and high antiknock value were reported, ranging from 2 to 8 gal. per 1000 cu. ft. of fixed refinery gas, yields varying with both the nature of refinery gas treated and processing methods. Assuming economic feasibility, regarding which there is still difference of opinion, gas polymerization offers the industry a possible outlet for its gases more in keeping with its basic chemical composition and value. The increased interest of railroads and heavy-duty truck and tractor manufacturers served to focus more attention on diesel fuels. The publicity given the Union Pacific diesel train, the Burlington "Zephyr" and others operated on special diesel fuels served to revive the intimations and fears of several years ago as to the ultimate replacement of the gasoline motor by diesel engines in even the passenger car field. How-

Jan 1, 1935

By Ronald Gibala

THE Au-Ni alloy system is one of many binary systems in which the supersaturated solid solutions may exhibit a multistaged precipitation behavior during aging. In addition to the equilibrium phase separation, which was studied extensively years ago in the range 400" to 600",' there exists at least one earlier stage of precipitation, i.e., preprecipitation, which occurs below 300°C in quenched alls.-This note reports on some effects of composition on the preprecipitation in Au-Ni alloys as determined from resistivity measurements. The kinetics of the preprecipitation were studied in alloys of 15 to 85 at. pct Ni which were water- were found in alloys which after various quenching-and-aging treatments were slowly heated and cooled (1Z"C per hr) between room temperature and about 300°C. Two such heating-cooling curves for a 40 pct Ni alloy are shown in Fig. 2. Similar effects were observed in other 15 to 50 pct Ni alloys. These curves are characterized upon heating by two changes in slope indicated by A and B in the figure and upon cooling by a resistivity hysteresis of approximately the size of the original decrease in resistivity after the aging treatment. The inflection at B generally falls at about the same temperature for all heating curves for a given alloy and appears to be a critical temperature (T,) for the preprecipitation for that alloy. The values of T, for most of the 15 to 50 pct Ni alloys fall in the range 200" to 220°C. The position of the inflection at A depends upon the heat treatment prior to the heating-cooling run and perhaps the heating rate, which was held constant in these runs. The preprecipitates grown in by the appropriate aging treatments seem to decrease in size as the alloys are heated from A to T,, dissolve at T,, and do not reappear after cooling below T,. When similar heating-cooling treatments were performed on 60 to 85 pct Ni alloys, an entirely different behavior was observed. Typical results are shown in Fig. 3 for an 85 pct Ni alloy. In these

Jan 1, 1964

By P. Pietrokowsky

RECENTLY a comprehensive investigation of the various sigma binary alloys was published by Duwez and Baen.1 It was shown that the following conditions are necessary for the formation of the sigma phase: (1) the difference in atomic diameters of the two alloying metals must not be more than about 8 pct; (2) of the two elements which form sigma, one must exhibit a body-centered cubic structure while the second metal must be face-centered cubic, at least in one of its allotropic forms. In addition, a tetragonal unit cell was proposed and powder patterns of six sigma phases were indexed for d spacings greater than 1.640 kx. Since the indexing, based on tetragonal symmetry, led to only fair agreement, the possibility of sigma being orthorhombic was investigated. Various methods for indexing orthorhombic powder patterns are de- scribed in the literature.' The method used in this investigation was a graphical examination of the differences in values of sin' 9 for the adjacent lines of the powder diffraction pattern. This method led to a complete indexing of the Cr-Co (60-40) pattern. Because of the strong similarity between the various sigma alloys, it was then possible to assign indexes to the patterns of Fe-Cr (50-50), Fe-Cr-Mo (30-30-40), Fe-V (50-50), Co-V (50-50), and Ni-V (50-50). The values of sin' 9 and indexes of the six sigma alloys, together with visually estimated intensities, are presented in table 1. In general, the similitude between the six patterns is quite good. For spacings greater than 1.75 kx a few differences are noticeable. In the Ni-V pattern, no (320) exists and the two strong lines (030) and (031) are separated by only two lines of lower intensity, unlike any of the other sigma patterns. However, very little is known about the Ni-V phase diagram and it is possible that the equal atomic percentage composition in this system lies in a two-phase region. At lower spacings there is a close analogy between the patterns. The planes

Jan 1, 1951

By Ralph Arnold

WHILE much geological work and drilling have been done in Venezuela, the incompleteness of geological evidence obtainable and the restricted areas in which drilling has been done make any estimates of oil resources extremely speculative. Nevertheless, it is felt that the data given are justified, in the belief that the ideas of a geologist familiar with the region are better than those of a promoter. The oldest beds of interest to oil men are those of the Cretaceous, which are well developed in eastern Venezuela and about parts of Lake Maracaibo. In both cases, a hard massive limestone is overlain by a great thickness, most of which is shale. In the west, in places this shale is more than 2000 ft. (610 m.) thick, while in the east it may attain 3500 ft., (1067 m.). The limestone and parts of the shale are oil producing. In the east, the Tertiary where present is almost entirely covered by the Quarternary, but in the west it is well developed. In probable unconformity over the Cretaceous shales is found a series of sandstones and shales, which may beg called the lower coal series. It is well developed southwest of the lake, where it is the oil container, and is probably the lowest series exposed east of the lake. Above this is the Pauji shale, which is probably the point of origin of all the oil east of Lake Maracaibo and in the State of Falcon. It has a thickness of about 3000 ft. (914 m.) in the Mene Grande region. The upper coal series is developed as a great thickness of sands, shales, and clays, with some partly consolidated limestone. Its thickness may be as great as 10,000 ft. It is the oil container of the Falcon-El Mene region and a probable location for oil in some of the area about the lake. It may or may not include the so-called Maracaibo series in which the oil is found at Mene Grande. Over much of Venenzuela, the Quarternary is present in unknown thickness, which probably is not great. It obscures oil structure in all cases and presents the greatest hazard of oil exploration for the fields which probably exist below.

Jan 7, 1922

By F. N. Speller

Interest in the corrosion problem seems to continue without abatement and is bringing practical results. At least four important conferences on this subject have been held during the last 5 months. Those interested in steel-frame structures are taking steps to study vulnerable points on account of the failure of some minor parts in certain buildings after 35 years of service. The steam power-plant group, including the railroads, realize the importance of a better knowledge of corrosion, especially under modern high-temperature boiler operations. The chemical and refrigerating industries have already conducted a systematic study of depreciation of metals by corrosion, for which they have spent considerable money and time during the last 2 years with encouraging results. More has probably been done to control corrosion in the atmosphere and in closed water systems, because the work on these phases of the problem started over 15 years ago and the important factors are now fairly well understood. As a result of all this work, there is now little excuse for corrosion in water conduits, recirculating condensers and cooling systems, since economical means of prevention have been worked out to meet nearly all situations where such corrosion occurs. The entire Baltimore water supply was treated with lime at a cost of only 35 c. per million gallons and the rate of attack on the pipes has been reduced to not over 20 per cent. of what it was before the treatment. Yearly damage to water mains in Baltimore is estimated at $300,000, and in New York City at $5,000,000, not including damage to water conduits in buildings. In some cities corrosion is now recognized by water works' engineers as a major problem. In the oil industry, there are evidently three general classes of corrosion, relating to: (I) Production, (2) transportation, and (3) refining. (1) Production.—Some fields, those of California for example, have little corrosion trouble in the wells. In others this is a major problem and should be a strong incentive to the development of more resistant metals at a reasonable cost. E. G. Woodruff,' consulting geologist, has pointed out that more of the oil of the future will probably come from the

Jan 1, 1927

HENRY TRAPHAGEN, * Toledo, Ohio (written discussion t).-The occurrence of flakes in steel is a perplexing problem, if we consider this condition as a disease rather than a symptom. But if considered as an exaggerated phase of a common disease, flakes will be recognized as old and well-known enemies. I have frequently found flakes in open-hearth steel, converter steel, and even electric steel; and not only in the so-called alloy steels but in dead soft 12-point carbon castings. In fact, I have some twenty flaky test bars that came from a foundry that manufactures converter steel castings. The physical characteristics of such material are striking in their constancy, for the yield point and elastic limit are always high, the elongation is variable, and the reduction of area is nearly always negligible. Soft steels of this kind can easily be bent to an angle of 150° and the only bad symptom is the appearance of incipient cracks on the surface; when the carbon exceeds 30 points, the bending qualities are seriously affected; and when the carbon reaches the neighborhood of 50 points, the bars are generally pulled short. The elongation is peculiar in that it seems to take place along the whole length of the bar, giving a crinkly appearance such as is found in cast brass and monel metal. Of course, this elongation only takes place in the softer varieties of steel. I have stated that flakes in steel represent exaggerated symptoms of a common disease, and that disease is the presence of higher oxides of iron. In every instance that has come to my attention, this condition is coexistent with the presence of oxides in some form. In open-hearth practice when this condition occurs, almost invariably it will be found that the metal has been loaded with ore or that tons of rusty turnings were being melted. In converter practice, one of three conditions is nearly always present: bad cupola practice, the use of oxygenated pig iron, or faulty tuyeres. With the electric furnace, my experience is quite limited, but the few examples of flaky electric steel that have come to my notice were made from a charge of turnings and low-grade light scrap.

Jan 6, 1919

By R. A. Wagstaff

The method of charging a reverberatory furnace has changed many times since smelting was introduced in this country from the old smelters of Swansea, England. The cause of the latest change at the Garfield plant has been the excessive fineness of the charge due to fine grinding in the concentration of the crude copper ores. The many desirable features of deep-bath smelting as now used at Garfield have been proved. The old method of dropping the charge through holes in the arch (known as center-feed method) causes excessive dusting which makes heavy slag and flue-dust losses, also rapid deterioration of the silica brickwork of the furnace through fusion with the iron oxides from the dust. The purpose of this paper is to describe a gun feeder that was designed to overcome the disadvantages of the older methods of center feeding and still maintain the good features of deep-bath smelting with the hot finer charge. A gun feeder was designed to introduce the finely divided hot calcines under the moving gas stream of the combustion zone and still have them spread in a uniform blanket over the highly heated matte bath. The temperature of the furnace was so great that it was impossible to maintain a stationary feeder, so a movable feeder was designed that could be introduced into the highly heated zone and be withdrawn after the charge had been dropped. It was necessary to protect the nozzle of the gun with a water-cooled coil. Many different types of protected nozzles were tried, such as air jackets, water jackets and heat-resisting steel alloys, but none proved satisfactory. The angle of inclination of the feeder was found to be an important factor in spreading the charge evenly over the surface of the bath. An angle of 34" to 37" was found to be the most advantageous. To allow a continuous flow of ore from the charge car to the point of discharge inside the furnace, the feeder was made with telescopic connections. The pipe leading from the car is stationary and forms the inside part of the telescope. The outside section of the telescope is movable, and is

Jan 1, 1934

By Joseph E. Pogue

The petroleum industry has been involved in Lore collective planning than any other American industry, with the exception of the railroads and utilities, and therefore is of interest as a case study in the experimental attempts to regulate the economic consequences of free competition. Planning is of course an integral part of effective management, hence at the outset a distinction must be clearly drawn between competitive planning and collective planning. By competitive planning is meant the aggregate of plans drawn up and prosecuted by the competing units occupying a field of enterprise; by collective planning is meant a collusion of plans, either originating among some or all competitors, or else imposed upon them, whether accepted or resisted, by some superior authority, usually the state. The prevailing popular concept of "planning" as applied to industry appears to be a program of conduct superimposed upon an industry unwilling or incapable of achieving a socially and economically desirable result under free competition. In this brief and tentative analysis of the subject, competitive planning is left to one side and attention is focussed upon the matter of collective planning as defined above. A basic functional difference between the two categories of planning is that in the case of competitive planning the individual plans are small, numerous, and tend to offset one another when in error; whereas in the case of collective planning, the separate plans are larger in scope, fewer in number, and tend to escape the incidence of the principle of compensation. In viewing the evolution of collective planning in the petroleum industry we find that during the past 20 years there have developed four more or less well defined collective plans and that at the present time the industry is deeply involved in a collective planning trend pointing toward further varieties. The four plans, which are to some degree transitional, may be conveniently named from the chief incidents that led to their formulations. The first collective plan was the program of control developed during the World War and hence called the war plan. The second plan was one originating within the industry in the period between the war and the inflation of the late twenties and called the inventory

Jan 1, 1935

During the year this Committee has had the benefit of the services of 75 Committee members, resident in the various States of the Union and in foreign countries, 10 of them representing us abroad. A number of plans for awakening the interest of possible new members have been carried out and the results have been very gratifying. The comparative results for 1913 and 1914 are as shown in the following table: 1913 1914 Applied for membership 630 946 Elected 450 1,006 Accepted election 433 921 When it is remembered that the depression following the outbreak of war in Europe has had more serious effect on the mining industry than almost any other, these results cannot be regarded as anything other than very encouraging. Because of the unsatisfactory conditions still prevailing it will doubtless be difficult to make even as good a showing next year. It is considered, however, that the function of this Committee is not merely to secure new members, having no regard for other than numbers; its true function is to exercise a proper supervision over the growth of the Institute, building it up in those fields in which it is weak, and directing its growth in such a way as to make it most effective in fulfilling its proper function as the national organization representative of the mining profession. The plan of inviting the alumni of the leading mining schools to apply for membership, which was initiated last year, was completed this year, with the exception of one or two schools, notably the University of California, from which we have not been able to obtain a list of alumni. With these exceptions we have now extended to the graduates of all the important mining schools of this country, and several of those abroad, an invitation to apply for membership in the Institute. It. is not thought desirable to repeat this invitation too frequently, and it is therefore suggested that this field be left alone for a year or two, when, if the mining industry experiences a marked revival of interest, it will be well to send out a second letter to the same men.

Jan 4, 1915

By F. J. Tuck

The Hayden mill of the Ray Mines Division, Kennecott Copper Corporation, is now equipped with two 9 by 12-ft. rod mills having a daily capacity of 6000 tons of coarse-crushing plant product from the mine. These two mills crush a ¾-in. product to approximately 19 per cent on 14 mesh, with only one pass through the mills. Each rod mill has taken the place of four sets of 42-in. Garfield rolls with their attendant screens, and is making a product for the fine-grinding department comparable to that formerly made by rolls in closed circuit with screens. The rod mills are lined with wave-type liners of white iron, varying in thickness from 2 to 3 in. The shell and end liners last approximately 600 to 700 days. Manganese-steel lifter bars, 3? in. thick, are used, spaced about 11 in. apart, and they give a life of 350 to 450 days. Fig. 1 shows the general design and thickness of the wave-type liners and lifter bars; 1½-in. liner bolts are used to fasten the lifter bars to the shell. The shell liners are held in place by the tapered lifter bars. A ¾-in. wood backing is used between the shell and the liners. The rod-mill scoop has removable manganese-steel lips, which last 250 to 300 days. The scoop proper has shown some wear in spots, and these spots have been protected by rubber bolted over them. Water and milk of lime are added to the elevator feeding the mill, but not enough water to cause a pounding of the rods against the shell. Roughly, the water added amounts to 25 to 33 per cent of the ore. Additional water is added to the mill discharge to facilitate distribution to the classifier bowls in the fine-grinding department. Rods are charged to the mill once every four days, the mill being down about 20 min. for this purpose. Other delays are negligible, and usually are due to a loose liner bolt or possibly power trouble. However, these occasions are extremely rare. In charging the mill, a crane is used

Jan 1, 1939

We note with sincere regret the death of H. T. Chen,, who was killed by forest fire in the mountainous re-ion of Kokiu-Chang where he had been operating as Engineer in Chief of the Yunnan Tin Trading Co. Mr. Chen graduated in 1911 from the Department, of Mines, .University of California, being the first Chinese Government scholar in mining to attend that institution; and one of the first in America. He came of a distinguished family, many members of Which are in official life in Peking and in his native province of Hunan, all of whom are noted for their classical scholarship. He was himself a Hsiao-tsai or Bachelor of Arts, a coveted degree of the old literati class, Which he won under the Manchu regime when he was still a stripling. His mining work in Yunnan was carried on with only the most primitive facilities and in a distant province, but was, nevertheless, attended with great success and profit for his company. The region is infested with brigands and rebellious troops. who frequently turn marauders and prey upon the countryside, and Mr. Chen has had to go to the mines always with a large armed guard sometimes aggregating 150 men and some hundreds of miners, also armed. Two armed squads of men keep in touch with his base 'at Kokiu-Chang every day to get supplies and food, and it is feared that the brigands who have thus been prevented from plundering and mobbing his parties have started 'he fires to burn him out, with the disastrous result reported. Mr. Chen has thus given his life to his country in the attempt to win for modern China and Chinese civilization the raw materials of her new industrial life. He did so cheerfully and with full appreciation of the dangers that beset him, and China regards this as one of the most noble sacrifices of her young sons on the altar of patriotism. He is survived by a daughter of two years and by his widow who was also a graduate of the University of California and will be remembered by her classmates as Lucy Kong, 1912.

Jan 7, 1917

By F. J. Tuck

The Hayden mill of the Ray Mines Division, Kennecott Copper Corporation, is now equipped with two 9 by 12-ft. rod mills having a daily capacity of 6000 tons of coarse-crushing plant product from the mine. These two mills crush a ¾-in. product to approximately 19 per cent on 14 mesh, with only one pass through the mills. Each rod mill has taken the place of four sets of 42-in. Garfield rolls with their attendant screens, and is making a product for the fine-grinding department comparable to that formerly made by rolls in closed circuit with screens. The rod mills are lined with wave-type liners of white iron, varying in thickness from 2 to 3 in. The shell and end liners last approximately 600 to 700 days. Manganese-steel lifter bars, 3? in. thick, are used, spaced about 11 in. apart, and they give a life of 350 to 450 days. Fig. 1 shows the general design and thickness of the wave-type liners and lifter bars; 1½-in. liner bolts are used to fasten the lifter bars to the shell. The shell liners are held in place by the tapered lifter bars. A ¾-in. wood backing is used between the shell and the liners. The rod-mill scoop has removable manganese-steel lips, which last 250 to 300 days. The scoop proper has shown some wear in spots, and these spots have been protected by rubber bolted over them. Water and milk of lime are added to the elevator feeding the mill, but not enough water to cause a pounding of the rods against the shell. Roughly, the water added amounts to 25 to 33 per cent of the ore. Additional water is added to the mill discharge to facilitate distribution to the classifier bowls in the fine-grinding department. Rods are charged to the mill once every four days, the mill being down about 20 min. for this purpose. Other delays are negligible, and usually are due to a loose liner bolt or possibly power trouble. However, these occasions are extremely rare. In charging the mill, a crane is used

Jan 1, 1939

F. JOHNSON,* Birmingham, England (written discussion t).--. Mr. Skowronski's first melting experiments tend to show that ingots with a "level set" may be obtained without oxygen. Now it is characteristic of all metals which occupy a smaller volume when solid than they do when molten to "pipe." In vertical-cast ingots, this pipe resembles a horn-shaped cavity, with the wide mouth uppermost. In horizontal-cast ingots, the pipe is a longitudinal furrow along the center-line of the ingot surface. If copper be successfully deoxidized and degasified, this furrow will inevitably be produced. In the author's oxygen-free ingots, it is. clear that gases were occluded and these gases effectively opposed the formation of a pipe or furrow by shrinkage (fluid contraction). It is riot a special property of any particular gas which produces this effect. Hence it is not surprising that the author has succeeded in producing level and overpoled ingots through the agency of sulphur. dioxide gas. That he has counteracted the overpoling influence of sulphur by means of oxygen is somewhat difficult to explain, since the well known reaction between cuprous sulphide and cuprous oxide should result in the production of sulphur dioxide gas. Why the presence of excess cuprous oxide should neutralize the overpoling influence of this gas without eliminating sulphur is not at all clear. It is to be regretted that the oxygen was not determined in the bars given in Tables 3 and 4. It is by no means established that sulphur is responsible for the over, poling of ingots given in Table 4, since carbon was used for overpoling. If, however, the same kind of poling treatment was given as that applied in the case of ingots in Table 1, the responsibility of sulphur assumes more definite shape. The author rightly points out that Mr. Johnson's theory of the equilibrium between gases and cuprous oxide does not explain why a simple addition of cuprous oxide does not correct an overpoled charge. Such a charge must be re-worked to "set" copper. This re-working (rabbling) undoubtedly forcibly removes the excess gases, which are not removable by cuprous oxide.

Jan 11, 1918

By John Howe Hall

The recently announced run of three years, nine months and eleven days made by a crucible steel melting furnace of the Columbia Tool Steel Co., which is claimed as a world's record, brings forcibly to our attention the great improvements that have been made in the design, construction and operation of the Siemens regenerative crucible melting furnace since its introduction in this country. Credit for this advance should be given to the furnace designer, the manufacturer of refractories, and the operators, of the furnaces, whose persistent efforts and intelligent co-operation in attacking the problem have resulted so satisfactorily. There are three factors that determine the life of a crucible furnace, or any other furnace for that matter: Design, nature of refractories, and conditions of operation (including the nature of steel melted); and to some extent these factors are interdependent. Thus, for instance, if a crucible furnace is to be operated single turn and allowed to cool off considerably at night, in order to save fuel, the use of clay-brick melting holes may be advisable, since silica brick is not well adapted to endure repeated heating and cooling. But the total life of a clay-brick melting hole is necessarily short. Again, if local conditions such as danger of flood make necessary the building of the furnace largely above ground, so that the radiation of heat is promoted, the cooling down of the furnace over the week ends, when no steel is melted, will be considerable—and the contraction of the furnace that results tends to wrack it to pieces. The character of the metal being melted affects the life of the furnace to a great extent. Low-carbon steels and steels made from iron and charcoal require higher temperatures and much longer melting time than high-carbon steel or steel made largely from scrap; the life of the furnace will be shorter, and the number of heats melted will be much less, when such materials are melted. The figures available, showing the life of furnaces, are for this reason especially not strictly comparative, since the variations in the steel melted undoubtedly affect the life to a greater or less extent. Probably, however, the method of handling is as important a factor

Jan 1, 1914