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By Thomas Fraser, David R. Mitchell

THE primary purpose of the loading plant is to transfer the finished product from the preparation machines to the railroad car, truck, or barge in which it is to go to market. Secondary purposes of the loading plant are: to prevent excessive degradation of sizes during loading, to reduce segregation as much as possible, and to prevent excessive quantities of very good or off-grade coal from entering any one car. Nonuniformity of consignments is one of the chief sources of com- plaints by consumers and coal merchants. A properly designed loading plant will do much to reduce complaints and ensure uniformity, not only from shipment to shipment but also in each individual consignment along the length of the car and in cross section. DEGRADATION IN STORAGE, LOADING AND SHIPMENT The object in loading is not only to handle the coal without breakage and segregation, but also to produce a well-trimmed load that will ride to its destination without spillage or breakage en route. The small sizes present in a car of prepared coal as received by the purchaser consist-of: missed small sizes not screened out in the preparation plant, breakage during loading, and breakage caused by handling en route. For domestic sizes of anthracite shipped from the Pennsylvania anthracite field to Atlantic coast cities, the dealers' lass because of breakage in loading and shipment amounts to from 2 to 5 per cent and for anthracite shipped to Middle West cities, the loss is 8 to 9 per cent. This difference is in part because dealers in the Middle West rescreen their coal more thoroughly than is usual in the East. One dealer handling Illinois No. 6 coal shipped from southern Illinois mines to Chicago reports an average size loss of 10 per cent when lump coal is unloaded with a fork. This runs as low as 5 per cent for carefully loaded coal and as high as 15 per cent for carelessly loaded coal.

Jan 1, 1943

By Noel Cunningham

MANY excellent descriptions of the mills of the, Porcupine district have been written, but no discussion exclusively devoted to the metallurgical technology has been given. These notes are intended to cover this feature briefly. They are based upon 2 ½ years' mill operation in the district-i.e., practically since the beginning of metallurgical operations. Character of the Porcupine Ore.-There is no oxidized ore in the district, the surface having been deeply planed by glacial action in recent geologic time. The precious-metal content is about in the proportion of 85 of gold to 15? of silver by weight; hence, the silver is practically negligible. There are two classes of Porcupine ore, having very different characteristics; these will be referred to throughout this paper as Class A and Class B. Class A ore is a pure quartz with inclusions of schist. Generally it is heavily fractured .and breaks down readily to sharp, hard grains, about minus 10 plus 20 mesh, requiring further comminution to release the gold. It carries very little pyrite; the gold is entirely free and apt to be coarse, but often spongy, going into solution readily on that account. This gold is 60 per cent. to 85 per cent. free milling, depending on the grade of ore. Class B ore is an iron silicate schist, strongly laminated, carrying 4 to 5 per cent. pyrite; its specific gravity is 2.8 to 3.0, depending upon the amount of mineralization. In breaking the ore in the mine, generally over 25 per cent. of material through a ½ -in. ring is made; the ore readily breaks down in milling and makes a comparatively large amount of non-crystalline slime; owing to its high specific gravity, however, it is quick settling.' In my opinion, the gold in this ore is free, but so finely divided that it will neither pan nor amalgamate; it appears to be disseminated through the rock and not chiefly associated with the pyrite. Veins of Class A ore occur with or without side walls of Class B, and veins of Class B occur unassociated with Class A; more often the veins are closely banded, Class A and Class B alternating, generally with Class B in excess. Both classes of ore are more-or less blocky at times, and with ref¬erence to Class B this is indicative or low gold content.

Jan 3, 1915

By J. Gordon Parr, A. J. Goldak

OgdEN et al.1 and Bumps et al.2 suggested that the solubility of aluminum in a titanium extended to 30 pct.* Sagcl,3 Clark and Terry,4 Anderko et al.,5 Ence and Margolin6 and Saulnier and croutzelles,7 subsequently proposed the existence of an intermetallic compound in the region of 25 pct Al. Although Anderko et al.5 suggested that the structure of this phase, Ti3Al, was of the DO,, (Ni3Sn) type, their conclusion was based only upon the results of a powder photograph that included reflections from ? = 0 to ?= 27° (CuK),some of which were reported to be indistinct. Ence and Margolin,6 referring to a 25 pct alloy (but without indicating whether the figure referred to weight or atomic pct) stated: "The structure of Ti2Al is isomorphous with Ti3Sn DO19, as pointed out by Pietrokowsky". But the point was not proven, because Ence and Margolin did not report values of calculated intensities of Ti2Al with the DO,, structure. In fact, the observed intensities they reported are in poor agreement with the values we calculate for DO19 (see Table I). Saulnier and croutzelle7 concluded, on the basis of electron micrography and microdiffraction studies, that the structure of the 25 pct A1 alloy was ordered hexagonal. Our purpose has been to unequivocally determine the Ti3Al structure. Alloys containing 25 pct Al were prepared from iodide titanium and spectrographic standard aluminum by levitation melting. The levitation chamber was evacuated to 10-6 mm Hg before filling with 99.999 + pct A. After casting, the alloy was chilled to liquid air temperature and crushed to -200 mesh in a percussion mortar. The powder, wrapped in molybdenum foil, was annealed (by induction heating) at 1000 "C for 2 hr in the argon atmosphere of the levitation chamber. No sublimate was seen on the foil or elsewhere, and therefore the assumption is

Jan 1, 1962

By J. E. Hanlon, S. R. Butler, R. J. Wasilewski

The temperature, orientation, and strain-rate dependence of tensile flow in single-crystal NiA1 of equiatomic composition have been investigated up to 800°C. Compression tests at room temperature have also been carried out. Optical and replica electron microscopy and X-ray diffraction methods were used to investigate the slip mechanisms. NiAl exhibits {110)(001) slip and cube slip {l00)(010) was also observed. This results in very high strength of single crystals in cube orientation. The implications of this slip mode, with the resultant small number of possible slip systems and three mutually perpendicular slip vectors, are discussed. ThE CsCl structure compounds represent a class related to the bcc elements, but their behavior is affected by three additional variables: composition (within the stability range of the compound), extent of long-range order perfection, and bonding energy. Very little data are available on the effects of these variables on mechanical properties. Rachinger and ~ottrell' suggested slip to occur along (111) in compounds of low ordering energy; in compounds of higher bond strength (>0.06 ev), they observed (110) (001) slip. As pointed out by copley,' only three in- dependent slip systems are available in the latter case; hence general deformation is impossible. Brown3 carried out a theoretical calculation of the yield-point variation with the degree of long-range order in the CsCl structure, based on the assumption of superdislocations. More general approaches, based on considerations of superlattice dislocations and antiphase domain boundaries in ordered structures, were carried out by Flinn~ and by Vidoz and Brown.' These, however, give no information on changes in the slip structure—if any—between the ordered and the disordered compounds. This aspect was investigated experimentally and theoretically by Stoloff and Davies' and by Marcinkowski and chessin7 in FeCo. The latter workers proposed the deformation behavior of the ordered FeCo to be essentially the same as that in many other bcc metals. Investigations of polycrystalline A~M~'-'O indicate considerable variation in mechanical properties with composition and test temperature. The existence of {123)(111) slip was reported in AgMg.'9'9'0 (The formation energy of this compound, presumed to be ordered at all temperatures below melting, is 4.38 cal per g-atom," i.e., 0.024 ev per bond.) The yield strength has been reported as relatively independent of temperature below 0.45 T, (where T, is the absolute melting temperature). Tensile deformation of single-crystal AgMg was also investigated by Kurf-man," who observed marked tendency to single glide on{112}(111) and {110)(111). From observations of slip lines in deformed poly-crystalline NiA1, Westbrook et a1.I3 suggested the

Jan 1, 1968

By D. Harker, E. Epremian

The constitution of the nickel-tungsten system has been studied by a number of investigators, the most recent of which are Ellinger and Sykes.1 On the basis of metallography, electrical resistivity and hardness measurements and some X ray diffraction work, they constructed a consitution diagram (Fig 1). Ellinger and Sykes report a0 for the alpha face-centered cubic phase (nickel saturated with tungsten) as 3.66?.‡ The gamma phase (tungsten saturated with nickel) is given as body-centered cubic, but no value of a. is recorded. At 43 pct tungsten by weight (approximately 20 at. pct) a beta phase is reported, but structure and lattice parameter are not known. Primarily on the basis of metallographic evidence, they conclude that beta is a new phase and rule out the possibility of formation of a superlattice since they- observe a new phase in the microstructure. Grube and Schlecht2 report an ordering reaction in a system similar to the Ni-W (Ni-Mo) and Harker3 has shown that NirMo forms a superlattice upon the pre-existing face-centered cubic lattice of the alpha phase. Elliniger arid Sykes observed a change in the diffraction pattern of a 4.3 pct W alloy upon aging and attributed it to the formation of a new phase. Thus, there appears to be some question as to the character of the beta phase reported by Ellinger and Sykes. The purpose of the present work is to determine precisely the structure and nature of the beta phase in the Ni-w system of X ray diffraction methods. Experimental Procedure One inch diameter ingots of 43.66 pct, 40.15 pct and 34.06 pct .tungsten by weight (19.8, 17.6 and 14.1 at. pct respectively) were melted and cast under vacuum from electrolytic nickel and pure wire filament grade tungsten. The ingots were soaked for 16 hr at 1300°C in a hydrogen atmosphere furnace, then swaged at this temperature and finally drawn to 0.020 in. diam wire. Some of the bar stock was retained in 1/2 in. diam rod for hardness and metallographic studies. Wire samples for diffraction work were sealed in evacuated quartz tubes and subjected to the various solution and aging heat treatments in a hydrogen furnace. X ray photograms were taken in a Debeye-Slierrer camera using copper K radiation filtered by nickel foil. Results X RAY DIFFRACTION The lattice parameters of the alpha and gamma phases at saturation were determined by an X ray photogram of the 19.8 at. pct W alloy after solution heat treatment at a temperature well within the alpha-gamma range above the peritectoid temperature (17 hr at 1150°C—oil quenched). The alpha phase was found to be face-centeted cubic with a. of 3.594 ± 0.001?, while the gamma phase was determined as body-centered cubic with a. of 3.158 ± 0.001?. Exactly the same phases and parameters were ohtained with the 17.6 at. pct W alloy for the same solution heat treatment. Thorough analysis was made of an X ray photogram of a 19.8 at. pct alloy sample in the quenched and aged condition (solution treated 1T hr at

Jan 1, 1950

The objective of the mission was basically to study the utilization of engineers and engineering technicians and their interrelationship in the Soviet Union. Beginning with their graduation from the engineering institutes and technicums, we hoped to learn how the graduates started out in industry, what their training on the job was, what sort of work they did, and how they worked themselves up within their profession. However, it turned out that, as our host was the Ministry of Higher and Secondary Education, most of our visits were to educational establishments. Our itinerary covered Moscow, Leningrad, Kharkov, Rostov, Baku, and Tashkent, with a side trip to Samarkand. In all, we visited 13 technical institutes, three technicums, and five industrial plants or enterprises, as they are called there. Our trip was one of only four weeks. Our observations were limited by the few cities and enterprises we were permitted to visit. Nevertheless, we did come back with some definite impressions and conclusions which we feel should be of interest to engineers, educators, and those concerned with the relative economic and technical power of the USSR and the U.S.

Jan 9, 1960

By J. M. Mutmansky, Y. J. Wang, H. L. Hartman

Procedures for determining the operating point that results when a fan is connected to a mine and placed in operation have been a source of confusion for decades. A variety of techniques have been proposed, often to the detriment of the practicing ventilation engineer trying to apply the techniques to the many mine/fan matching problems encountered in the engineering of mine ventilation systems. This paper proposes some different assumptions and definitions that simplify the problems in determining the operating point. As a result, a set of procedures is provided for determining the operating point of a mine/fan system when the outlet areas of the mine and fan are known. To simplify the development of procedures for determining the operating point for a mine/fan combination, the authors suggest that the mine pressures be redefined and then used in such a manner that the conservation of energy is ensured. This provides the basis for the recommendation that the fan operating point be determined using the fan total pressure and the system total pressure characteristics. This procedure can be applied to fans in the blower, booster, and exhaust positions equally well, and to both single-fan and multiple-fan networks. Another advantage is that the method is applicable to fans with or without an evase.

Jan 1, 1986

By William E. Ford, Edward Salisbury Dana

5. Crystallography. - The subject of Crystallography includes the description of the characters of crystals in general; of the various forms of crystals and their division into classes and systems; of the methods of studying crystals, including the determination of the mathematical relations of their faces, and the measurement of the angles between them; finally, a description of compound or twin crystals, of irregularities in crystals, of crystal- line aggregates, and of pseudomorphous crystals. 6. Definition of a Crystal.- A crystal * is the regular polyhedral form, bounded by smooth surfaces, which is assumed by a chemical compound, under the action of its intermolecular forces, when passing, under suitable conditions, from the state of a liquid or gas to that of a solid. As expressed in the foregoing definition, a crystal is characterized, first, by its definite internal molecular structure, and, second, by its external form. A crystal is the normal form of a mineral species, as of all solid chemical com- pounds; but the conditions suitable for the formation of a crystal of ideal perfection in symmetry of form and smoothness of surface are never fully realized. Further, many species usually occur not in distinct crystals, but in massive form, and in some exceptional cases the definite molecular structure is absent. 7. Molecular Structure in General.- By definite molecular structure is meant the special arrangement which the physical units, called molecules, assume under the action of the forces exerted between them during the formation of the solid. Some remarks are given in a later article (p. 22 et seq.) in regard to the kinds of molecular arrangement theoretically possible, and their relation to the symmetry of the different systems and classes of crystals.

Jan 1, 1922

By Thomas O. Ziebold, Robert E. Ogilvie

Experimental analysis of diffusion samples covering the entire Cu-Ag-Au system at 725°C has been carried out. Experimental coefficients are computed at twenty-eight points in the lermary system. It is found that the direct coefficienl for copper is nearly independent of the silver, content for 1ow-silver alloys and that the cross coefficient for silver correlates with the ther-nzodynatnic properlies. This lalter observalion leads to the conclusion that the mobililies of copper and gold are nearly equal. Thermodynarmic actiuilies for Cu-Ag-Au were computed from binary data and adjusted to be consistent with neasured tie lines across the two-phase region which extends into the ternary diagram at 725°C. Application of these therknodynarnic calculaliorls to the dijftcsion data terifies the Onsager reciprocal relations to the extent that experimental uncertainlies will allow. It is jound that diffusion neav the critical point of the 1200-phase field in the isothermal section at 725°C causes the composition gradients for copper and silver to approach infinity while the direct and cross coeficients become equal. From the standpoint of experimental Procedures, it has been shown that microanalysis of ternary samples may be carried out using a simple expression for the conversion of X-ray zntensily to composilion. The accuracy of' this method has been demonstrated by the analysis of standard alloys and by the reproducibility of composition determinations using differed X-ray lines. DIFFUSION in a ternary alloy system is basically and significantly different from diffusion in binary alloys. When only two elements are present there is just one independent composition variable, and the diffusion profile of composition vs distance across a sample must change monotonically through all solid solutions bracketed by the terminal alloys. If two-phase regions are stable for compositions between the terminal values, these must appear as planar interfaces in the diffused sample, with the composition profile exhibiting sharp discontinuities. Adding a third element may alter this picture completely. Because of the additional degree of freedom in the composition, we may see composition profiles which do not change monotonically through solid-solution ranges, and stable, nonplanar phase interfaces. Even though two-phase regions may lie between the terminal compositions of a diffusion sample on the constitution diagram, they will not necessarily appear in the diffusion profiles. In binary diffusion only one coefficient is needed to describe the interdiffusion process. From Fick's law this coefficient relates the diffusive flux of one component to its own composition gradient. In ternary diffusion we must allow for cross interaction between the two independent species. By a linear extension of Fick's law we introduce "cross" or "off-diagonal" diffusion coefficients which relate the flux of one component to the composition gradient of the other independent constituent. Thus, we require four interdiffusion coefficients to describe the transport process in a ternary system. In its most general form,1,2 the rate equation for mass transport by isothermal diffusion in a system of s components states that the diffusive flux of component i, Ji, is a linear summation of all driving forces, Xk, each force being multiplied by an appropriate compliance coefficient:

Jan 1, 1968

By Morris Steinberg, John Wulff, Robert Kamm

IN powder metallurgy it has often been observed that shrinkage may occur in one direction and growth in another during sintering. Even in long-time sintering experiments the rate of shrinkage may be different in different parts of the compact. In the fabrication of some parts requiring a constant permeability it is even questionable in some cases whether pressing from one direction should be attempted. These observations require for their interpretation a more detailed study of green or pressed density than has heretofore been available. Usually average density measurements of the whole compact are made and in some cases carefully cut sections are measured. A different approach to the problem was first mentioned by Rakowski1 and also used by Balshin.2 Balshin's diagram is reproduced in Fig r and schematically shows the result of pressing three layers of metal powder with fine intervening layers of graphite. The retarding effect of the die walls and a qualitative example of the density distribution is evident. More quantitative information about the distribution of density within a cold-pressed powder compact would be useful in showing the variation in density in compacts as influenced by the type of powder, shape of die, lubrication during the process, and other variables. Furthermore, information about the cracking of cold-pressed compacts may be obtained from an analysis of the stress distribution within a powder compact, and some information about the stress distribution can be obtained in turn from the density and strain distributions. A more detailed report on some of the present experiments appears in reference 3. PRESENT INVESTIGATION In order to ascertain the density gradients in cold-pressed metal powders, a deformable lead grid within the powder was employed. After pressing in cylindrical dies the ejected compact was radiographed, giving a pattern of the deformed grid. From the radiograph density and deformation from point to point is readily measured. From the radiograph strain distribution and stress trajectories were also determined. The latter also permits the determination of the coefficient of friction at the die wall. This technique indicates that the densest part of a compact pressed from one side is at the top outer circumference and the least dense region at the bottom circumference near the stationary plunger. For some heights of compacts the density at the axis is such that the lower density is at the top rather than at the bottom. So irregular a density distribution is due primarily to die-wall friction. As the ratio of diameter to height of compact is increased the die walls play a correspond¬ingly smaller role. More uniform density

Jan 1, 1947

By A. Steiner, E. Miller, K. L. Komarek

Equations have been derived to calculate the chemical potentials of the components of liquid binary alloys from liquidus and enthalpy data. The equations are applicable to systems with intermetal-lic compounds of limited solid solubility. The liquidus curve of the Mg-Sn system was accurately redetermined, and the melting point of the compound Mg2Sn was found to be 770.5° * 0.3°C. The thermo-dynamic properties of the liquid alloys were calcu -lated from the liquidus data. The activity of tin shows both positive and negative deviations from Raoult&apos;s law and the relative integral entropy is positive. THE phase boundaries in an equilibrium phase diagram are functions of the thermodynamic properties of the coexisting phases. Specifically, the shape of the liquidus curve near an intermediate compound is determined by the properties of the compound and the liquid phase. Hauffe and wagnerl have derived an equation for the chemical potential differences (ui) of the liquid alloys near the congruent melting point when the heat of fusion of the compound and the liquidus curve are known. In their derivation the temperature dependence of the ui value was neglected, and liquid of stoichio-metric composition was chosen as the reference state. To obtain chemical potentials over the ntire composition range of the phase diagram with the pure components as the reference state, equations have been derived which incorporate the temperature dependence of the chemical potentials. Such a thermodynamic analysis can be carried out when the liquidus curve and the enthalpy values are known. The equations have been applied to the redetermined liquidus curve of the Mg-Sn system to obtain the thermodynamic properties of liquid Mg-Sn alloys. The Mg-Sn phase diagram has been studied by various investigators and the results have been compiled and critically assessed by Hansen.2 Preliminary thermal analyses showed that the basic features of the diagram were correct. The system has one congruent melting compound, Mg2Sn, two eutectics, and some solid solubility of tin in magnesium. However, the published liquidus temperatures show considerable scatter. In order to perform an accurate thermodynamic analysis, the liquidus curve between the magnesium-rich and tin-rich eutectic compositions was therefore redetermined by careful thermal analysis using highest-purity starting materials. EXPERIMENTAL PROCEDURE The magnesium metal (Dominion Magnesium Ltd, Toronto, Canada) had a purity of 99.99+ pct with the following impurities (in ppm): 20 Al, 30 Zn, 10 Si, <1 Ni, <1 Cu, <10 Fe; tin (Cominco Products, Spokane, Wash.) contained 99.999+ pct Sn. The graphite crucibles were machined from graphite rods (United Carbon Products Corp., Bay City, Mich.) which had an average total ash content of less than 30 ppm. All the graphite parts were baked out in vacuum at 950" to 1000°C for a minimum of 24 hr to remove volatile organic materials. The graphite crucibles (3 in. long, 1-5/8 in. OD, 1-3/8 in. ID) were tightly closed with a threaded cover (1/2 in. thick) which had a central thermocouple well (2-1/4 in. long, 5/16 in. OD, 3/16 in. ID). Cover and thermocouple well were machined from one piece of graphite. A thin sheath of quartz was inserted in the well to protect the thermocouple

Jan 1, 1964

By B. S. Butler, H. D. McCaskey

The New London copper mine, about 8 1/2 miles east of Frederick, Md., was visited by the writers for a few hours in the spring of 1909 and the following brief notes on ore specimens collected are presented as a contribution to studies in chalcocite ores. For certain data on the structural and areal geology of this portion of Maryland the writers are under obligation to the unpublished notes and maps of Arthur Keith. The detailed study of the ores is the work of B. S. Butler. The deposit here discussed has many similarities to those of the Virginia district of Virginia and North Carolina, which have been described by Gratonl and Laney,2 except that in the deposits of the New London mine chalcocite is by far the most important ore mineral, while in the Virginia deposits bornite is commonly the most important sulphide. In the New London occurrence calcite is the most important gangue mineral. Field relations The -town of Frederick lies in the center of a narrow belt of limestone ranging in age from Ordovician on the east to Cambrian on the west. This belt is about + mile wide at Noland&apos;s Ferry, on the Potomac, and broadens to a width of 3 miles at Frederick. The general direction is east of north. The eastern boundary is, in places, a fault plane along which a series of metamorphic rocks of presumptive pre-Cambrian age have been thrust up. These ancient rocks, for several miles east and west of New London, are phyllites in the main, but closely inter-folded near the New London mine are long, narrow lenses of epidote

Jan 1, 1915

By C. R. Van Hise

Introduction.............29 The Three Zones of the Lithosphere ..30 Zone of fracture............31 Zone of flowage............ 31 Factors influencing depth at which flowage occurs.. 32 Zone of combined fracture and flowage.. 33 The Water-Content and Openings in Rocks....36 Condition of rater in the zone of fracture.. 36 The openings in rocks...........38 Size and number of openings..... 40 Ore-deposits derived from zone of fracture..45 The source of underground water......... . 47 The cause of the flowage of underground water..47 Belts of underground circulation.. 51 Upper belt of underground circulation.. 51 Lower belt of underground circulation.. .... .52 Capacity of water for work in the lower belt of underground circulation........... 53 Movementsof water in the lower belt of underground circulation. 54 The preferential use by water of large channels.. 60 Physico-Chemical Principles Controlling the Work of Under ground Waters..........62 Chemical action............63 Underground aqueous solutions..64 The relations of solution and temperature..... 65 The relations of solution and pressure..66 Precipitation........... 67 Precipitation by change in temperature..68 Precipitation by change in pressure..69 Precipitation by reactions between aqueous solutions.. . 69 Precipitation by reactions between liquid solutions and solids. 70 Precipitation by reactions between gases and solutions. and solids............71 The General Geological work of Underground Waters.. . 71 Division of the zone of fracture into a belt of weathering and a belt of cementation............72

Jan 1, 1901

Charles H. Morgan, Worcester, Mass. (communication to the Secretary): In connection with Mr. Douglas&apos;s mention of the continuous charcoal kiln used at Kopparberg, some further data concerning this important invention may be of interest. Before giving these, however, I will say a word or two concerning other features of Swedish practice. In 1894 I spent two days at Soderfers with Mr. Tom Bergendal, the manager of the works, and was specially interested in the gas-producers and wood-drying kiln, illustrated in the paper contributed to our Transactions by Mr. Odelstjerna in that year.* The wood-drying kiln is, however, quite different in design and construction from Ljungberg&apos;s charcoal kiln. In the summer of 1894 it was discovered that by placing the gas-producer as close as possible to the open-hearth furnace, and working the producer hot, ordinary weather-dried wood, still containing a considerable percentage of moisture, could be used to advantage in the melting-furnace. Hence, the dryingkiln was needed for wet wood only. One of the iron-works of the Udeholm Go. was the first to adopt the Lundin saw-dust gas-producer and condenser, enabling them to make gas from saw-dust containing 45 per cent. of moisture, and convey the gas from the condenser through wooden pipes to the Siemens steel-melting furnace.† This sawdust gas gave very satisfactory results in iron-works; but the proprietors experienced much trouble by reason of the pollution of rivers by the tar-water from the condenser. On my visit, in 1894,I found that the Udeholm Co. had put in for their steel-melting furnaces the same wood-gas producers

Jan 1, 1899

By D. F. Hewett

ALTHOUGH most persons will agree that an individual or a nation can profit from the experience of other individuals or nations, there is always room for debate over the degree of similarity of their past and present conditions and of their future problems. Noting the increasing interest that Americans are showing in our mineral problems, I have felt that we could profit from reviews of the experiences in mineral exploitation acquired by the industrial nations of Europe. Whether we can learn much from Europe&apos;s experience in exploiting such minerals as petroleum may be debatable, but certainly, with a record of metal production extending back nearly 3000 years, Europe should hold much of value for America. A trip to Europe in 1926 permitted me to visit 28 mining districts, of which about half are now or have been in times past outstanding sources of several metals. The districts range from England to Greece and from Spain to Poland. To summarize briefly my impressions of these mining districts, as well as such reactions to the thought and life of Europe as so short a visit permits, I shall only venture the opinion that Americans can review with great profit the ideas and actions of Europeans, with regard not only to the production of metals but to many expressions of life. I believe that America has made and is making new contributions to the art of living, as well as to the arts of mining and metallurgy, but in so far as Europe is and has been a laboratory of economic, social and political experiments, the results she has attained deserve the thoughtful attention of America. I have come to believe that many of the problems that harass Europe lie in our path not far ahead. I have therefore hoped that a review of metal production in Europe in the light of its geologic, economic and political background may serve to clear our vision with regard to our own metal production. One can not examine the literature of national metal production without being impressed that the countries of continental Europe, especially Germany and Austria, have shown greater interest and devoted more time to research into the record of metal production than Great

Jan 1, 1929

By Sir Robert Hadfield

LAST year this Institute was good enough to accept some remarks by the writer regarding sound steel, entitled Plant for Hadfield Method of Producing Sound Steel Ingots, being a continuation of a research in which for some time the writer has been engaged, and full particulars of which were submitted in papers entitled A New Method of Revealing Segregation in Steel Ingots, and Method of Producing Sound Ingots, read before the Iron and Steel Institute in October, 1912. These papers gave rise to a very interesting discussion, both in England and America. This question is one of vital importance, as unless sound steel in the form of ingots is first obtained, sound steel in the finished forms of rail billets, rails, bars, sheets, and other forms cannot be expected. The working stresses demanded by modern conditions are so great, each year they probably approach nearer to the limit of safety, that without doubt those who produce steel will be compelled to pay the attention which this subject deserves. Moreover, the problem is not an insuperable one, as shown by the writer in the papers above referred to. In view of the information which has already been presented in these papers, it is not now necessary to go into details of the system advocated by the writer, except to repeat that the ingots and steel now referred to were produced by employing in the first place sound fluid steel, free from blowholes, this being poured into ordinary ingot molds, provided with the necessary feeding heads, the insulating slag medium, also charcoal and air blast or other suitable form of applying heat to the head portion of the ingot. Tile upper or head portion of the ingot is kept fluid by the intense heat generated by the air blast and charcoal, so that such fluid steel passes into the body of the ingot below the head, thus feeding and avoiding the shrinkage or piping which would otherwise occur. The result is the production of a sound steel ingot, free from blowholes, segregation and piping, and in which the waste portion, usually termed the discard, is but little over 7 or 8 per cent.

Jan 4, 1914

Professor Sir John Cadman, K. C. M. G. (1918) D. Se., F. G. S., M. Inst. C. E., was for two years Technical Adviser&apos; of the Chemical Warfare Department and Liaison Officer between British and French Forces. The Cross of Officer of the Legion of Honor was awarded him in 1917 by the President of the French Republic "in recognition of valuable services rendered by him in the cause of the Allies." At the moment, Sir John is Director of the Petroleum Executive and Chairman of the Inter-Allied Petroleum Conference. In 1915, he was Technical Adviser of the Trench Warfare Supply Department and was awarded C.&apos;M. G. in 1916. J. Edwards-Leckie, C. M. G., D. S. 0., went to Valcartier as second in command of the 72d Regiment, Seaforth Highlanders of Canada, with rank of Major, and later sailed for France as second in command of the unit now known as the, 16th Battalion, the Canadian Scottish. He was promoted to Lieutenat-Colonel on Aug. 14, 1915, and returned to England to take command of the 2d Canadian Reserve Training Brigade at Shornecliffe. On Jan. 2, 1916, he was promoted to Colonel. R. G. Edwards-Leckie, Lieut.-Col. of the 72d Regiment, Seaforth Highlanders of Canada (which unit later became known as the 16th Battalion, The Canadian Scottish, and under that name distinguished itself in France), left Canada for "Over There" on Sept. 14, 1914. He was promoted in France to the rank of Brigadier-General on Aug. 14, 1915, and served until severely wounded in February, 1916. He was Acting Chief of the General Staff, Canadian Overseas Forces in England from September to December, 1916. He returned to Canada in May,

Jan 8, 1918

K. Baumgarten has returned from active service in France. He reports that he saw C. W. Campbell, formerly with the 2d Engineers on the Chateau Thierry front, and believes that the latter returned to the United States on August 1. He also saw J. J. Croston; G. J. Sielaff, recently transferred to the Gas Service; Thomas M. Smither, survivor of the Tuscania after a 10-mile swim to Ireland. While in Paris he en-deavored to see Prof. Sauveur, but was unsuccessful. F. K. Borrow was given a commission as Lieutenant in the Royal Garrison Artillery in 1914, but had to relinquish it, on account of ill health, in August, 1915. His health has much improved and he hopes to resume active work toward the end of this year. Davis, A. W:, see British Columbia Engineers, below. Alfred Fox, Jr., enlisted in the Public Schools Brigade, Royal Fusiliers, in September, 1914; was gazetted Lieutenant in the Royal Field Artillery in December, 1914, promoted to Captain in November, 1915, and Adjutant to 78th Brigade, Royal Field Artillery, in January, 1916. He was appointed Staff Captain of the 12th Divisional Artillery in November, 1917. He has served continuously in France since July 1, 1915. He was awarded the Military Cross in January, 1917, and four times mentioned in despatches. E. Fraser-Campbell writes that he joined the London University 0. T. C. in January, 1918, for five weeks; enlisted with the Argyll and Sutherland Highlanders in February, 1918, and attended a training course for officer cadets at Chatham for six weeks. He was commissioned 2d Lieutenant, Royal Engineers, in April, 1918. After two months on home training at Chatham, he landed in France on June 23, 1918, posted to 180th Tunnelling Co., R. E., and is now with his unit up on the line.

Jan 10, 1918

Ore deposits of commercial grade are local concentrations of great rarity when considered in relation to the area of unmineralized land surfaces, and they must therefore be considered as the products of exceptional and complex conditions. The data collected from a great number of individual deposits are sufficient to permit certain broad generalizations in regard to the conditions favorable to ore deposition which even numerous exceptions do not invalidate. The broadest general relation of ore deposits is with intrusive rocks, and while there are notable exceptions, the great majority of ore deposits have a visible or closely inferred connection with intrusive rock masses. Conditions that permit the dissipation of the ore-bearing vehicles do not permit the concentration of metals in deposits; the prime factor to consider in this connection is that structural conditions must be such as tend to concentrate and not to dissipate the ore-bearing solutions. The disadvantage of extrusive rocks is at once apparent; any metals the magma may have contained are dissipated at the surface and are lost; with the exception of tiny vugs and cracks in quickly cooled flows, no concentrations of metals are known in extrusive rocks, and the lack of confinement and quick cooling apparently do not permit extrusives to exert mineralizing effect upon the rocks with which they come in contact. The close mineralogical similarity between extrusives and intrusives, and the great difference in mineralizing power is a proof of the ease with which magmas part with their metallic content, and of the mobility of the ore-bearing vehicles in comparison with the parent magma.

Jan 1, 1932

By S. M. Wu, R. L. Stone, T. D. Tiemann

The dissolution of silica from quartz in sodium hydroxide solutions was investigated by statistical methods. A second-order predicting equation was developed with 28 experiments expressing the dissolution of silica as a function of the variables quartz size, time, temperature and sodium hydroxide concentration. With this equation a comprehensive picture of the dissolution reaction was gained which included the effect on extraction of each variable and their interactions, fractional extractions, reaction rates and activation energies. A previous investigation of the extraction of silica from low grade siliceous iron ore by digestion in sodium hydroxide solutions presented the extraction as a function of time, temperature and sodium hydroxide concentration.&apos; The present paper is an outgrowth of the previous work and develops by a mathematical analysis the functional relationship between the extraction of silica and time, temperature, sodium hydroxide concentration and particle size. Relatively pure quartz was used in this study in order that the basic quartz-sodium hydroxide reaction could be studied without the influence of other constituents that are commonly found in iron ores. The functional relationship between the dissolution

Jan 1, 1965