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H. A. SCHWARTZ, ? Indianapolis, Inc. (written discussion§).-Re-ferring to the very interesting paper on the graphitization of white cast iron, the writer desires to present certain facts and conclusions, entirely, in harmony with those of the authors but which may he not without interest as furnishing additional evidence upon the same subject. The graphitization of white cast iron, being the basis of malleable

Jan 10, 1919

EDWARD HART*, Easton, Pa. (written discussion?) .-In 1895 I visited the chemical plant of the Messrs. Chance at Oldbury, England, under the guidance of Mr. France, the manager. In the stock house I saw a pile of coal brasses with adhering coal and said to Mr. France, "I should think you would get dark acid." "Yes," he replied, "our acid has always been rather black. and our customers have grown used to it. Some time ago we ran out of brasses and could get only Spanish pyrite. Our product became white and the customers began to complain, so I put a little sugar in each carboy." E. A. HOLBROOK,* Pittsburgh, Pa. (written discussion?).-Mr. Davis says, "A very large tonnage of pyrite is annually being thrown in the waste in the coal mines of this country." This quantity is much larger than is generally realized by people not intimately associated with coal mining. At the beginning of the war this country seemed threatened with a short-age of pyrite. The U. S. Bureau of Mines conducted a general investiga-tion of the pyrite resources of the country in order to ascertain what material was commercially available. The general pyrite investigation was in charge of H. A. Buehler, with the subsection on coal pyrite in charge of E. A. Holbrook.

Jan 10, 1919

Book Review MANAGEMENT AND MEN. By Meyer Bloomfield, Boston. The Century Co., New York, 1919, pp. 584, H.X. 5 1/2. $3.50. This hook is an exposition of English efforts to solve the problem of labor unrest in England. The first six chapters are reprinted from articles published in the Satur-day Evening Post, for whom the author went to England to study the problem at first hand. These articles deal with housing, increased production, eliminating the internal friction in the industrial machine and a chapter each devoted to the view-point of employer and employee. These chapters are written in the easily readable magazine style and give a complete general survey of the particular solution being tried. Perhaps their greatest., certainly not their least, worth lies in the fact that they form a vehicle for unusually voluminous appendices containing in full the famous Whitley Reports which are the basis of the new movement, together with various reports, which, except for this publication, would be largely inaccessible to those inter-ested in this country. The Whitley scheme considers each industry a unit and proposes to establish therein a Joint Standing Industrial Council composed of representatives of employers and employees to consider appropriate matters affecting the industry at large. There is to be a District Council for each industry which will, as its name implies, deal with the clatters pertaining to that interest in. the particular district. The third and last body in this scheme of Industrial Parliament is the Works Committee, which is com-posed of representatives of the management and of the workers employed in particu-lar plants or mines to act in close cooperation With the district quid national machinery. The Whitley or similar schemes have been tried in many communities in England and the book contains interesting comments on the result obtained, it being notable that most of the objections conic from plants which have not tried the scheme. Meyer Bloomfield, the author; is the specialist in industrial personnel problems who organized the industrial service activities of the United States Shipping Board, Emergency Fleet Corporation. P. E. B.

Jan 10, 1919

A. MALINOVSZKY,* Belleville, Ill. (written discussion?).-I have been very much interested in Mr. Dolman's paper. We all realize, I think, that this question of developing our home industries and support-ing the new industries which have developed during the great war is very important at present. Mr. Dolman has well shown the quantity and quality of the raw magnesite in the United States, and the commercial and industrial possibility of our home magnesite and I believe, with him, that our home industries should receive adequate protection. There are two reasons, however, for believing that this may be difficult. One reason is that much American capital is invested in the Austro-Hungarian magnesite industry. The raw magnesite can be quarried and prepared for the market in Austria with much cheaper labor expense than in the United States; large deposits which are very easy to quarry and good transportation facilities also contribute to the cheapness of production. The second reason is the old saying that the magnesite found in the United States is not of the same quality as the Austro-Hungarian mag-nesite; this I doubt. Even if the magnesite found here does not in a raw state equal the Austro-Hungarian, it can be synthetized so that the finished article will have the same properties as the Austro-Hun-garian finished magnesite refractory possesses. Thaw magnesite from Greece is not the same as the. Austro-Hungarian, but it has linen demon-strated that a good refractory can be made from the Greek product.

Jan 10, 1919

HENRY M. Howe, Bedford Hills, N. Y (written discussion*).¬Mr. Foley's explanation of this interesting occurrence is perfectly reasonable. Possibly a word explaining the phenomenon more in detail may not be amiss. In the act of solidification each drop as it starts to solidify splits up into a half drop poorer in carbon and another half drop richer in carbon than the drop itself. The half drop poorer in carbon solidifies and attaches itself to-the already solid walls, whereas the half drop richer in carbon remains molten for the excellent reason that it is richer and hence is more fusible than the original drop, and hence in turn is wholly fusible at the existing temperature. Under usual conditions, as when the steel solidifies in a mold of any form, the successive molten half drops thus enriched in carbon remain present and by their enrichment progressively raise the carbon con-tent of the remaining molten mass, out of which successive half drops are continuously solidifying and attaching themselves to the already solid walls. Because the molten mass thus. becomes progressively richer

Jan 10, 1919

LUTHER B. EAMES, Pueblo, Colo. (written discussion*).-In reading Mr. North's interesting paper, several points have been noted that appear to warrant discussion. With a feed all through 20 mesh, I feel inclined to question the use of steel balls as large as 2 in. in a tube mill. I have seen balls as small as-3/4 in. used for the dry grinding of cement clinker, and surely many more points of contact would result from smaller balls. This would seem to be desirable in a mill as short as 6 ft. The heavy load in the classifiers would also indicate a high proportion of returned pulp. I hope that some discussion by Mr. North -and others may develop this point. The flow sheet on page 1181 shows the solution returning from the dam valued at 40 c. per ton being added to the last decantation tank. Theoretically, this solution should not be added to that of a lower value. As I calculate it, if this solution were added to tank X the solution finally discharged from tank Z would be reduced in value by nearly 4 c. per ton.

Jan 10, 1919

J: H. POLHEMUS, New York, N. Y. (written discussion*).-The Joplin .mining and milling practice has largely influenced operating methods in the Wisconsin district. Milling equipment is essentially of the same type with the notable exception that no tables are used. The treatment of the flue 'sands has been attempted several times but without commercial success. Table material coming from any one mill is low both in tonnage and zinc content. The iron is comparatively high as the pyrite-line "chat" is much more prevalent than the zinc-lime attached particle. In the finer sizes the zinc occurs mainly as free mineral. These condi-tions make the production of good-grade table concentrates very diffi-cult. The accompanying tabulated results from several mill tests indi-cate the character of the mill tails. I think the average mill tails in the district assay nearer 1.5 per cent. zinc than under 1 per cent., as stated by Messrs. Boericke and Garnett.

Jan 10, 1919

R. MOLDENKE, Watchung, N. J. (written discussion*).-It is some-what difficult to discuss the paper of Mr. Stork, when the description of the cupola melting occurrences indicates that his practice is open to question. The evident burning of much of the steel charged,. coupled with the remarkably low silicon content of the mixture as shown by the resulting product, throws the entire melting practice into that of making cupola malleable. If anything is wanted here, it is a. high bed to melt upon, and yet Mr. Stork in the very beginning of his paper speaks of the evils of oxidation due to a "high" bed, etc. The experienced foundry-mall would judge at the outset that Mr. Stork has kept his bed in the cupola too low, and naturally got a lot of oxidation from the blast. The oxidation of steel when used in large quantities in cupola mixtures is a well-known phenomenon, and is readily understood. One has but to. put a file into the forge fire and watch it burn when heated high enough. The melting point of steel being higher than cast iron, heavy pieces may dig way into the bed before being completely melted away, the last por-tions being directly exposed to free oxygen from the blast. Another situation not to be forgotten is the oxidizing effect of carbon dioxide at high temperatures. A serious oxidation of the steel is quite conceivable if in the zone of maximum carbon dioxide and minimum carbon monoxide-free oxygen being entirely absent. Hence the well understood practice of never melting a mixture with much steel unless the bed is kept exceed-ingly high; or again the above-mentioned malleable practice. Mr. Stork mentions the impossibility of deoxidizing a heat. after the steel contained has been oxidized. This is true to a great extent with the ordinary deoxidizers, such as silicon and manganese, but can be brought about by vanadium, titanium, magnesium, etc. Proper melting, however, makes this unnecessary.

Jan 10, 1919

ARTHUR F. BRAID,* New. York, N. Y. (written discussion ?). -I have read Mr. Cain's paper with a very great deal of interest. The subject is one that is worth a great deal of thought and research at this time. It is a well-known fact that the strong affinity of steel or, iron for oxygen is perhaps the main detriment to sound production, and, as the author states, it is-indeed remarkable that today there are no analytical methods in general use in steel works for determining the gaseous con-stituents of steel.

Jan 10, 1919

F. C. LANGENBERGW.*at 8ertoivn,M ass. (written cliscussiont).-I am inclined to the view that the change in physical properties encountered in the material with which the authors are working is due to the relief of internal strains. The statement, on page 1.098 of their paper, calling attention to the fact that this phenomenon disappeared when the material was rolled into 1 7/8 -in. square billets is of particular interest. It is certain that the internal strains set lip by cooling in a small billet of this size would be much less than those produced in a billet having a larger cross-section cooling under the same conditions. The statement that the physical properties of a given test bar were materially changed by standing has been brought to my attention in connection with the testing of gun forgings. I have made a number of observations on forgings produced at Watertown Arsenal to ascertain whether any change in ductility was produced by the aging of the test specimens. The results were always negative, but this can be explained by the fact that ii gun forging is generally a forging that has been quenched and subsequently drawn at a relatively high temperature.

Jan 10, 1919

By Edward Hyde

THE HIGH-TEMPERATURE SCALE IN OPTICAL PYROMETRY AT the basis of optical pyrometry lie the theoretical and experimental data of the so-called blackbody. The black body is essentially a theoretical conception, with certain simple properties attributed to it -fundamentally, the property that its radiation at any temperature is a unique function of the temperature and does not involve any other variables. As a theoretical conception, an equation has been developed by Boltzmann connecting the total radiant power with the temperature, and another equation by Planck connecting the distribution of radiant power throughout the spectrum with the temperature. The integral of the latter with respect to wave-length conduces to the former and permits the evaluation of the constant c1 of the Planck equation, ass given in the form. J-= cl?-5 c2 (1) e ? T ? 1 assuming that the constant Q of the Stefan-Boltzmann law E=a(T4-T40) is known. The other constant c2 is arrived at by other methods, which will be discussed later. This equation for the black body lies at the foundation of optical pyrometry. To make the discussion complete, it should be stated that the theoretical black body is quite closely realized by a hollow enclosure with walls at a uniform temperature and radiating through a small orifice. The electrically heated black body, first introduced by Lummer and Kurlbaum, is an essential part of the equipment of a pyrometric research or testing laboratory. Numerous investigations have shown that its radiation conforms to that of the theoretical black body within experimental errors. Hence by operating the electrically heated black body at the melting point of some pure metal for which the temperature of melting has been determined on the vas scale. a standard is obtained for comparison with

Jan 9, 1919

By Joseph Ames

THERE are two distinct questions associated with the concept of temperature: one is practical, the other is theoretical. Our fundamental ideas of temperature come from our senses; we know what we mean by the words "hot" and "cold," or by saying one body is "hotter than another." But for scientific purposes words require definition. We are guided in this matter, as in all other scientific questions, by our knowledge of facts of observation. When two bodies at different temperatures are intimately associated, e.g., a hot stone is, dropped into a pail of water, our experience is that ultimately they come to the smile temperature as far as our senses can tell; the hot body becomes colder and the cold body hotter. In the case of a block of ice, immersed in, water, the ice melts, forming cold water, which then mixes with the other water, the final result being water colder than the original water. From our knowledge of the nature of heat phenomena, we learn that in this process one body loses, heat and the other gains heat, the condition of equilibrium being, one in which each body gains Is much heat as it loses. It is distinctly assumed in this statement that only two bodies are concerned in the transfer of heat, all other bodies being rendered in some way impervious to heat. The body that in the process loses heat is said to have the ?higher temperature" while the body that gains the heat is said to have the "lower temperature;" and, when thermal equilibrium is reached, the two bodies are said to have the "same temperature." Consequently, the temperature of a body may be defined, is it was by Maxwell, as "its thermal state considered with reference to its power of communicating heat to other bodies."

Jan 9, 1919

By Charles Brush

THE general subject of accurate pyrometry, its great development in recent years, and the importance of its application in arts and manufactures is so ably treated in other papers that this paper will bee confined to a resume of some research work on certain temperature effects in carbon and other steels, some of which appear to, be new. The results of these researches are embodied in several papers presented to' various scientific societies during the last few years, most of them under the general title of Spontaneous Generation of Heat in Recently Hardened Steel.1 Several years ago, when studying the behavior, tinder certain conditions, of specimens of hardened tool steel, I observed that they all spontaneously generated a small quantity of heat, the rate of generation diminishing from day to day for several weeks before generation became imperceptible in the sensitive calorimeter used. In each case the steel had been hardened only a few days prior to its use. It seemed highly probable that the generation of heat was associated with some sort of "seasoning" or incipient annealing process, perhaps accompanied by slight changes of volume, and that it would be most rapid immediately after hardening. I subsequently investigated this curious phenomenon more fully. Twelve ½ in. round bars of tool steel, 5 in. long and with machined surfaces, were hardened by heating to high cherry red in a reducing atmosphere of a gas furnace and quenched in cold water. The bars then had a thin strongly adhering coating of black oxide. They were next stirred in a large quantity of water at room temperature, to acquire that temperature, wiped dry, and oiled with heavy, neutral mineral oil to prevent generation of heat by further surface oxidation, wiped free of excess of oil and placed in the copper cylinder of a heat-insulated box.

Jan 9, 1919

By Robert Hunt

The American Institute of Mining and Metallurgical Engineers was the first American technical organization to consider steel-rail specifications and sections. If I am not mistaken, the first contribution on those subjects to the Proceedings of the Institute was presented by Prof. Thomas Egleston, in 1874, and was entitled "Investigations on Iron and Steel Rails made in Europe in the Year 1873.1" The next contribution was Dr. C. B. Dudley's report of his investigation for the Pennsylvania Railroad of the wear of steel rails in their tracks, in 1878, which contribution led to a very memorable discussion that extended through several meetings.2 In 1880, Mr. C. P. Sandberg3 presented an article on rail specifications and inspection and rail sections. This was followed, in 1881, by A. L. Holley,4 in his exhaustive report on the then used American rail sections. The next contribution, I believe, was made by myself' at the Buffalo meeting, in 1888, on steel-rail specifications, which I followed,6 in 1889, by a paper on steel-rail sections. Since that time there have been numerous contributions to the Transactions of the Institute in relation to the manufacture of steel rails. The American Society of Civil Engineers officially took up the investigation of the relation of rail sections to the wear of car wheels in 1888. In the prosecution of this work, the Society appointed a special committee, whose labors extended through several years and resulted in an exhaustive report to the Society in 1893.7 Later, another committee was appointed to consider specifications for the manufacture of steel rails; the labors of this committee extended over a period of several years, a final report8 being made in 1910. It was my fortune to be the secretary of both of those committees.

Jan 9, 1919

By Zay Jeffries

IT has been known for a number of years that certain aluminum alloys could be hardened by quenching from a temperature of about 500° C. Immediately after quenching the total increase in hardness is not marked, but the hardness increases gradually so that after about 4 days, it has reached a maximum. The actual increase in hardness probably continues for weeks or even months, but in order to detect the differences after 4 days, it is necessary to make tests at rather long intervals. So far as is known to the authors, Alfred Wilm was the first to discover these properties in aluminum alloys.1 The aluminum-copper alloys are amenable to this treatment and the addition of magnesium makes the heat-treatment effect more pronounced. Until recently heat treatment of aluminum alloys has been confined to the worked alloys in the form of sheet or extruded products. The alloy that has been most used in this connection is known commercially as duralumin and has about the following composition: copper not exceeding, 6 per cent.; magnesium not exceeding, 2 per cent.; manganese not exceeding, 1 per cent.; commercial aluminum,2 balance. A typically good alloy in this range consists of: copper, 4 per cent.; magnesium, 0.5 per cent.; manganese, 1 per cent.; commercial aluminum, balance. This alloy can be rolled into sheets or extruded; and in this condition it can be heated in the ordinary furnace atmosphere to a temperature near 500° C. and quenched in water. After about 4 days it will have the following physical properties: tensile strength 55,000 to 60,000 lb. per sq. in. (3866 to 4218 kg. per sq. cm.); elongation in 2 in., 15 to 20 per cent. No harmful effects of the furnace gases or even the air, if the heating is affected in an electric furnace in an air atmosphere,

Jan 9, 1919

Taking advantage of the lessons in administrative organizations which were taught by the war, Director Van H. Manning has put into effect a new form of organization in the Bureau of Mines. The Bureau is divided into two branches, one the investigations branch and the other the operations branch. F. G. Cottrell, who has been chief metallurgist of the Bureau, has been promoted to the position of assistant director and will be in charge of the investigations branch. F. J. Bailey, who has been chief clerk of the Bureau, has been placed in charge of the operations branch with the title of, assistant to the director. All research and technical control will be exercised through the investigations branch, while the non-technical work, administrative duties, and dissemination of the results of the Bureau's activities will be handled by the operations branch. Under the investigations branch comes the division of mineral technology, in charge of Dr. C. E. Parsons; the division of fuels, under the chief mechanical engineer, 0. P. Hood; the division of mining, under the direction of George S. Rice, the chief mining engineer; the division of petroleum and natural gas, under the direction of J. 0. Lewis, the chief petroleum technologist; and the division of experiment stations, under the direction of D. A. Lyon.

Jan 9, 1919

By C. F. Smart

THE heat treatment of the bronze composed of 88 per cent. copper, 10 per cent. tin, and 2 per cent. zinc, has been investigated by H. S. and J. G. S. Primrose,1 and also by the U. S. Bureau of Standards.2 The results obtained by H. S. and J. G. S. Primrose on dry-sand castings subjected to reheating followed by air cooling, or by quenching in water, are shown in Figs. 1 and 2. The values for tensile strength have been FIG. 1.-EFFECT OF QUENCHING ON DRY SAND CASTINGS (H. S. AND J. G. S. PRIMROSE.) converted from tons per square inch to pounds per square inch. Figs. 3and 4, have been plotted from values obtained by the Bureau of Standards on material of the same composition and treatment. Both investigations show that the ductility of the cast bronze is improved by heating to 700° C. and cooling in air, the strength not being impaired by this treatment. They are not in agreement, however, as to the effect of quenching, Messrs. Primrose reporting a decrease, and the Bureau of Standards an increase, in both strength and ductility when the cast bronze is heated to 600° or 700° C. and quenched.

Jan 9, 1919

By Geo Ashley

THE following paper is intended to be suggestive only, and to open the way for discussion and further observation. Its preparation was requested only two days before the time limit set for the submission of the papers comprising this symposium. Thus no time existed for detailed studies so it is largely a memorandum of such facts as have come incidentally to the notice of the writer in the study of coal in the field. The field study of sulfur in coal has received very little special attention or description from coal students. The presence of sulfur concretions is noted in hundreds of descriptions, and certain benches of a coal bed may be described as "sulfury" or the presence and position of sulfur bands may be noted in coal sections in connection with sampling. It may be accepted that some sulfur is present in all coal. The amount varies greatly in different regions, in different beds, and in the same bed in different areas. The anthracite of Rhode Island comes the nearest of any coal known to the writer of being free from sulfur, several analyses of that coal showing less than 0.1 per cent. Subbituminous coals in Colorado in a few places have close to 0.2 per cent. of sulfur on the dry-coal basis and in other states subbituminous coals approach this lower limit. Bituminous coals seldom run under 0.4 per cent. of sulfur on the dry basis, though in a few places dry bituminous coals in Colorado and Washington have between 0.3 and 0.4 per cent. The better known bituminous coals have almost everywhere over 0.4 per cent. The best of the Pocahontas and New River coals run close to 0.4 per cent., but there is very little commercial coal in Pennsylvania, Ohio, Indiana, Illinois, Kentucky, or the other states that runs under 0.5 per cent. on the dry basis. From these minimum figures, the amount will range up to 5 or 6 per cent. or higher if visible sulfur is not excluded. It must be remembered that the usual -analysis of a coal bed is not intended to give the total proportion of sulfur in the bed but the amount in the coal after the removal of the more obvious and larger sulfur masses.

Jan 9, 1919

By F. A. Harvey

DURING the last few years, there has been a constant tendency toward increasingly high temperatures in many lines of industry. The necessity for increased production of coke gave a 16-hr. coking period where we used to have 24 or even 30-hr. periods. Mechanical stokers have increased the temperatures in boiler furnaces. The use of a chain-grate stoker with coke-breeze fuel necessitates a low arch in the furnace and temperatures run much higher than firebrick were formerly called upon to stand. These higher temperatures have necessitated more rigid tests and the separation of even high-grade firebrick into separate classes. More severe tests mean higher temperatures and closer control, and this, in turn, means better pyrometer tubes. Platinum couples do not have a very long life when used at temperatures exceeding, say, 1200° C., but the proper selection of a high-grade brick to be used in a-boiler setting will save the cost of several couples; and with freight rates continually increasing it becomes increasingly important to know where brick may be bought, nearest the job, that will prove satisfactory. Couples that will stand continuous use at higher temperatures, of tungsten, molybdenum, or other metal, will doubtless be forthcoming as soon as the need becomes sufficiently urgent. There are on the market several tubes that are entirely satisfactory for temperatures up to 1300° C., if properly protected from heat shock. The Semet-Solvay Co. makes a practice, however, of testing silica and clay firebricks at 1450° C. for 72 hr., and so far we have been unable to find a tube that- is entirely satisfactory for this purpose. A graphic record of the temperature during the entire test is extremely desirable and hence we have been trying out anything that gave promise of success. Several years ago we were using insulating tubes, made purely for electrical work, of vitrified porcelain. These tubes stood up under any temperature we were able to reach and were apparently impervious to gases. When this stock gave out, due to mechanical breakage, we tried other insulation tubes only to have them melt down like glass. Marquardt Masse tubes were tried next under a statement from the distributors

Jan 9, 1919

By W. W. Odell

THE sulfur content of coal is perhaps more important in the manufacture of illuminating gas than in any other coal-using industry. Whether the gas is made by the distillation of coal in retorts or ovens or by steaming incandescent coal or coke in the water-gas process, a portion of the sulfur present in the fuel always passes into the crude gas. Practically all the sulfur that remains in the finished gas is transformed into sulfur dioxide (SO2) when the gas is burned. Sulfur dioxide is a pungent suffocating gas and, if present in the air in any perceptible amount, is deleterious to health and comfort and damaging to house furnishings. So universally is this recognized that laws regulating the amount of sulfur that may be permitted to remain in the gas are very generally in force. The capacity of a plant to purify gas frequently limits the selection of coal for gas making. This condition may arise from different causes. Some plants were originally designed to handle a certain grade of low-sulfur gas coal, and very little leeway was allowed for growth or for the use of inferior coals. Other plants, when built, had ample capacity to purify gas from relatively higher sulfur coals, but their output has grown so rapidly that their purifying capacity is now limited and only- the low-sulfur coals can be handled. There is a great quantity of coal in the United States that would satisfy the requirements of the gas manufacturer, were it not for the high sulfur content. The coals containing less than 1 per cent. sulfur are becoming scarcer year by year and, in time, the gas industry will probably be compelled to use coals that are now considered out of the question.

Jan 9, 1919