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By Ralph A. Sherman, John Blizard

The experimental investigation described in this paper was conducted to determine the relative combustibilities of different samples of blastfurnace coke when burned in a current of air in a small furnace. It was undertaken in connection with the work done by Perrottl and Kinney2 on the process of combustion in the blast-furnace hearth.3 Reference is often made to the "combustibility" of coke by blastfurnace men, but exactly what is meant by the term "combustibility" is somewhat vague. Brassert,4 in a paper before a meeting of blastfurnace men in 1914, refers to combustibility as follows: The value of the coke in relation to the heat reactions in the furnace is determined not only by the carbon content but even more so by its combustibility. This, in turn, is governed by its size, the physical and chemical composition of the carbonaceous substance forming the cell walls, and the interior and surface structure of the coke pieces. These properties are, in turn, influenced by the chemical and physical properties of the coals used for coking, the density of the cake of coal in the oven, the coking time, temperature and heat regulation of the ovens, and last, but not least, by the method of quenching, screening and handling the finished coke. What principally concerns the blast furnace is the rate of progression of the combustion, which depends not so much on the chemical analysis as on the physical qualities of the coke. It is this rate of progression that we term combustibility, which is the speed at which the carbon molecules in the coke combine with oxygen under given conditions. In general, what the blast furnace requires is a coke which will burn rapidly and with intensity at the tuyeres, yet which has a sufficiently strong structure and hard surface to resist abrasion and solution by CO2 in the upper part of the stack.

Jan 1, 1923

By John Blizard, Ralph A. Sherman

The experimental investigation described in this paper was conducted to determine the relative combustibilities of different samples of blastfurnace coke when burned in a current of air in a small furnace. It was undertaken in connection with the work done by Perrottl and Kinney2 on the process of combustion in the blast-furnace hearth.3 Reference is often made to the "combustibility" of coke by blastfurnace men, but exactly what is meant by the term "combustibility" is somewhat vague. Brassert,4 in a paper before a meeting of blastfurnace men in 1914, refers to combustibility as follows: The value of the coke in relation to the heat reactions in the furnace is determined not only by the carbon content but even more so by its combustibility. This, in turn, is governed by its size, the physical and chemical composition of the carbonaceous substance forming the cell walls, and the interior and surface structure of the coke pieces. These properties are, in turn, influenced by the chemical and physical properties of the coals used for coking, the density of the cake of coal in the oven, the coking time, temperature and heat regulation of the ovens, and last, but not least, by the method of quenching, screening and handling the finished coke. What principally concerns the blast furnace is the rate of progression of the combustion, which depends not so much on the chemical analysis as on the physical qualities of the coke. It is this rate of progression that we term combustibility, which is the speed at which the carbon molecules in the coke combine with oxygen under given conditions. In general, what the blast furnace requires is a coke which will burn rapidly and with intensity at the tuyeres, yet which has a sufficiently strong structure and hard surface to resist abrasion and solution by CO2 in the upper part of the stack.

Jan 1, 1923

By L. E. Murr, P. J. Smith

A study has been made by transmission electron microscopy of thin foils of 304 stainless steel fatigued external to the electron microscope in reversed bending, and of thin foils fatigued directly within the microscope in alternating tension. The build-up of stacking faults in the thin foils during fatigue zoas correlated with the dislocatirm structures found in thin films prepared fror fatigued bulk specimens. The performance of the special devices designed for fatigue of thin foils so outlined and the importance of alternative methods of preparation of more uniform fatigue specimens bY vapor deposition are emphasized. INVESTIGATIONS on fatigued bulk aluminum1,' and stainless stee13j4 have revealed the existence of dislocation substructure on examination by transmission electron microscopy of electrolytically thinned foils representative of these bulk specimens. While this technique has proved extremely valuable, it has several shortcomings. First, the method of fatiguing bulk specimens and then thinning to foil for electron-transmission observation allows only one observation of internal structure at any one portion of the fatigue life. Second, thinning the bulk fatigued specimens to foil results in the loss of at least one original surface. Thus, what one sees in the remaining electron-transparent sections is an internal dislocation or fault structure which in many cases cannot be correlated with the original surface markings. This is an undesirable feature, since it is well-known that metal surfaces play an important part in the fatigue process.5 An obvious third undesirable feature of the thinning-from-bulk technique is the fact that static observations have difficulty (in the case of fatigue) explaining the mechanism of a dynamic process. What is required then is a method whereby a selected thin area can be continuously observed either while undergoing cyclic deformation or at various fixed stages of fatigue deformation. While Murr and wilkov6 have reported some success with an apparatus designed to fatigue thin metal foils directly within the electron microscope, the nature of the specimen-mounting procedure and the mechanical features involved in the adaptation of the fatigue device to the electron microscope make this method difficult to operate. It was not possible, for example, to make frequent observations of a selected area because of difficulty in maintaining a chosen area in a stable viewing position inside the electron microscope. Except for the build-up of a dislocation substructure and what are commonly referred to as "slip striations", little else has been reported from observations on thin-foil sections prepared from bulk fatigue specimens. segal17 has found "slip striations" in stainless-steel fatigued specimens which were electropolished from both sides, but gave no explanation as to their origin or identity in terms of lattice imperfections. The research to be reported in this paper was undertaken with the following objectives in mind. First, an attempt was made to devise a technique or techniques whereby thin metal foils could be fatigued and repeatedly observed by transmission electron microscopy. Second, it was hoped that some correlation could be made between deformation striations found in fatigued thin transmission specimens and thin foils prepared from bulk fatigued specimens. These investigations illustrate quite convincingly that a feasible method is available for the direct study of the fatigue mechanism and similar dynamic phenomena in thin transmission specimens inside the electron microscope. I) EXPERIMENTAL METHODS Three modes of specimen fatigue and observation of fatigue damage were used. These involved fatigue of thin-foil specimens in a special arrangement external to the electron microscope and observation of a selected area at various stages in the fatigue life, the fatigue of thin-foil transmission specimens inside the electron microscope, and the fatigue of bulk specimens external to the electron microscope followed by thin-foil preparation for direct observation at predetermined stages. Design of the External Fatigue Clip and Specimen Holder for the Hitachi H.U.11 Electron Micro-scope. The purpose of the fatigue clip was to provide a reversed bending fatigue stress to a thin-foil transmission specimen outside the electron microscope. In order to accomplish this, a flat-bottomed, U-shaped brass clip was made as shown

Jan 1, 1965

By H. C. Rickaby

BY August 1944 Canada expects to be shipping 56 percent hematite ore from its new Steep Rock iron mine, via Port Arthur on Lake Superior, to the steelmaking centers in Canada and the United States. This is indeed welcome news to steel men, especially if they operate open hearth furnaces, as the Steep Rock ore is a high-grade lump and will be valuable as charge and feed ore. But better news is the fact that this first big producer of high-grade hematite ore in Canada, since the exhaustion of the Helen mine in the Michipicoten area north of Lake Superior in 1918, has a proved ore body of 16,757,000 long tons and a probable ore body of 14,000,000 long tons, thus giving an over-all total of 30,757,000 long tons and assuring production for a number of years to come.

Jan 1, 1943

By Marsh S. Watson, Robert A. Howard

An electrolytic model study has been made of the relative productivity of perforated casing. The results show that the relative productivity is roughly one-half to two-thirds of that predicted from point-sink calculations. This discrepancy can he satisfactorily explained on the basis of casing interference. The relative productivity was found to he insensitive to spatial arrangement of the perforations. INTRODUCTION The relative productivity of wells with perforated casing has been treated mathematically by Muskat.' In his treatment the perforations are represented by small spheres, thus enabling him to approximate the flow by that to point sinks. By neglecting interference between the flow into the various spheres representing the perforations, one may deduce the approximate formula Qu 1/rp - 1/rw • (1) I + b/2n _________ 2n In re/rw Where Q is the flow rate into spherical sinks located in the median plane of the sand laver Qo is the open hole flow rate (uncased hole of radius rw) b is the thickness of sand layer under consideration (always one foot in this paper) n is the number of spherical sinks in the sand layer rp is the radius of a spherical sink rw is the well radius re is the drainage radius of the well. Fig. 1 is a comparison of values calculated from equation (1) with Mus-kat's values. It will be observed that the approximate values are in error by less than 21/2 per cent. The disturbing effect of the casing on the flow line; is not explicitly taken into account by Muskat, but he reasons that interference between the flow pat- terns from the various point sinks will result in a negligible flow in the region within the well radius, and that no appreciable error will result from not explicitly excluding flow from this region. This line of reasoning is open to question, however, as the flow impedance, in the immediate vicinity of the well, of a hemispherical cavity in contact with an opening in the casing is twice that of a spherical sink in a continuous sand layer. There will be a difference, moveover, between the flow into a hemispherical cavity and that into a circular hole in the casing. .This latter difference can best be appreciated by comparing the flow from a semi-infinite medium into a hemispherical cavity at the edge of the medium with the flow out of a circular opening of the same radius as the hemisphere and which is also on the edge of the medium. In this case2 ------= —2, showing that the difference in flow rates into differently shaped cavities is quite appreciable. It was the purpose of the investigation reported here to determine to what extent flow into circular perforations in casing departs from the values calculated by Muskat. For this purpose an electrolytic model was used.

Jan 1, 1950

By Edwin B. Eckel

THIS paper, based on brief field examination and on data supplied by the operators, records the condition of the Italian mercury industry as of March 1945, not long after Italy's collapse. Except for the once-Italian but now Yugoslavian Idria mine near Trieste, virtually all the known mercury deposits are in the Monte Amiata district in Siena and Grosseto Provinces, 75 miles north of Rome. This district contains the Abbadia San Salvatore, the Siele, the Argus, and the Cerreto Piano mines besides numerous prospects and unproductive mines. Under pressure from Germany the principal mines were highly productive during the early part of the war, but production fell off long before its end. All of the mines were damaged in some way at the German withdrawal but by September 1944 the Abbadia had resumed production and several others were only lacking power by the early spring of 1945. The Monte Amiata district is characterized geologically by a thick series of sedimentary rocks that range from Triassic to Eocene in age and are surmounted on Monte Amiata itself by a thick cap of extrusive trachyte. Bodies of travertine and of landslide detritus, younger than the trachyte, are rather widespread. The structure is complex and little known but most of the ore deposits seem to lie along or near a major, north-trending fault or on associated cross-fractures. Cinnabar is the only important ore mineral and clay minerals are by far the most abundant products of hydrothermal alteration. A southward increase in the amount of stibnite, relative to cinnabar, suggests horizontal zoning. The grade of ore ranges from 0.60 to 3.0 pct and the reserves, as compared with those in American mines, are enormous. Even in the face of war-time scarcities, the mines are remarkably self-sufficient and labor is plentiful, but the costs of production are estimated to be not greatly below those of the better American mines. Notes on the principal mines, on the mining and metallurgical methods, and on the manufacture of synthetic cinnabar are included in the paper.

Jan 1, 1947

By H. E. Sadler, B. Silliman

INTRODUCTORY NOTE. THE research here recorded was undertaken early in the present year, and has been prosecuted steadily for about eight months. While the work has been under my constant supervision and advice, the labor has all been performed by Mr. Sadler, to whom is chiefly due the development of the successive steps which have led to the final result. The process is better than I dared to hope, and we are able to place at the command of chemists and engineers interested in the matter an apparatus of continuous and uninterrupted action, and methods of analysis by which the daily averages of the two variable and inconstant factors of illuminating gas, ammonia and sulphur, may be determined with all needful accuracy, even by those little skilled in chemical manipulation, and with very little loss of time. This research has been carried out in the laboratory of the New Haven Gaslight Company. B. SILLIMAN. October 17th, 1876.

Jan 1, 1877

By Francois Clerf

IRON ORE fields are situated in both the East and West of France (see maps). The eastern deposit is by far the most important from a tonnage point of view, not only in France, but in all Europe. The ores of this region are known as minette, and are situated in the Lorraine ore fields and the Briey plateau. The iron ores of the West are those of Normandy, Anjou and Brittany. Before the war, a large number of important German companies had acquired considerable interests in these western fields and a heavy trade with Westphalia had begun. Recently, however, conditions have changed and some of the mines of Brittany and Anjou are now idle. From a geological point of view, in Anjou and Brittany, a series of synclines extends from the northwest to the southeast, containing a number of seams of varying thickness and generally intercalated in Silurian and sometimes in Devonian formations. The ore is generally a hematite or a magnetite. The composition varies from 48 to 52 per cent of iron and from 8 to 12 per cent of silica. Con¬servative estimates indicate a con¬siderable tonnage of workable ores (150,000,000 metric tons).

Jan 1, 1936

By David White

In these days, when detailed investigations of stratigraphy, structure, and sand conditions so frequently result in the discovery of new oil fields, and applause from oil companies and the public, geologists do well to walk humbly, and punctiliously to admit that the geologic principles controlling the distribution of oil and gas have as yet been discovered only in part, and that what remains yet to be learned is probably vastly more than what is already known. The few experiments already attempted have been fragmentary, and somewhat desultory, and however positive each of us may be with respect to certain theoretical conclusions, many of the fundamental questions as to the origin and mode of occurrence of petroleum are subject to radical disagreement. Of the chemical changes attending the generation of petroleum from organic matter, little is actually known. Most of the postulated formulas are liable to be misleading, through ignorance of essential factors. Open-minded-ness is therefore a prime essential at the present stage of our science. Nevertheless, adopting the hypothesis that oil originates in some manner fundamentally connected with the organic theory, and in possible departure from such open-mindedness, the writer will pay no attention to the so-called inorganic theory, since every attempt to apply this theory to the study of old oil fields, or to the discovery of new ones, affords cumulative evidence of its inadequacy. In this paper, some of the factors affecting the occurrence of petroleum that the writer believes worthy of consideration by the prospector for oil in any new region will be discussed. Some of these, which arc less generaLly understood, will be considercd somewhat in detail. Other points, the significance of which cannot now be determined, require more field study, and for that reason are here brought to the attention of the field geologist. On the other hand, certain theoretical points which do not bear especially on the oil possibilities of a new region will be given little or no attention. The main topics that will be discussed are: (1) sufficiency of carbonaceous detritus and residues in the oil-forming rocks; (2) stage of carbonization of the organic matter in the oil-bearing formations; (3) folding of the strata; (4) thickness of sedimentary formations; (5) conditions of deposition.

Jan 1, 1921

By Donald E. Cummings

Measures appropriate for the control of the silicosis hazard in mining cannot be formulated precisely, but sufficient knowledge1-l9 has accumulated during the past quarter century to permit the suggestion of useful, though partly empirical, rules for its alleviation. The industrial hygienist today recognizes that the peril incurred by the inhalation of harmful dust is a function of two variable factors—the degree of harmful exposure and the specific susceptibility of the exposed individual to pulmonary injury. Control of the danger arising out of prolonged contact with pernicious airborne particulate matter is consequently best exercised by influencing both of these recognized variables. Obviously the problem has two broad aspects—one, medical; the other within the province of the engineer. I—Factors Comprising Degree of Individual Susceptibility Thorough investigations conducted among miners who have labored for years in the presence of recognized silicosis hazards usually reveal an impressive difference in the injury incurred by men whose exposure to dust has been nearly identical. After a quarter century underground, one individual is short of breath and incapacitated with miners' complaint, while a fellow workman suffers no pulmonary embarrassment and is in good health. Physicians ascribe this oft-observed difference in reaction to individual susceptibility and express a universal regret when they deplore the fate that chose to make the predisposed youth a miner rather than a farmer. To trust the health of miners to fate at the present time is even more unfortunate, because many of the factors that influence man's susceptibility to dust are known, and can be accurately determined by competent medical methods. Among the most important factors comprising susceptibility to injury by dust are the anatomical peculiarities of the individual's respiratory mechanism, his physiological response to the inhalation of dust, his previous dust, exposure, the existence of pulmonary infections or other pathological processes in his lungs, his age,

Jan 1, 1940

By Donald E. Cummings

Measures appropriate for the control of the silicosis hazard in mining cannot be formulated precisely, but sufficient knowledge1-l9 has accumulated during the past quarter century to permit the suggestion of useful, though partly empirical, rules for its alleviation. The industrial hygienist today recognizes that the peril incurred by the inhalation of harmful dust is a function of two variable factors—the degree of harmful exposure and the specific susceptibility of the exposed individual to pulmonary injury. Control of the danger arising out of prolonged contact with pernicious airborne particulate matter is consequently best exercised by influencing both of these recognized variables. Obviously the problem has two broad aspects—one, medical; the other within the province of the engineer. I—Factors Comprising Degree of Individual Susceptibility Thorough investigations conducted among miners who have labored for years in the presence of recognized silicosis hazards usually reveal an impressive difference in the injury incurred by men whose exposure to dust has been nearly identical. After a quarter century underground, one individual is short of breath and incapacitated with miners' complaint, while a fellow workman suffers no pulmonary embarrassment and is in good health. Physicians ascribe this oft-observed difference in reaction to individual susceptibility and express a universal regret when they deplore the fate that chose to make the predisposed youth a miner rather than a farmer. To trust the health of miners to fate at the present time is even more unfortunate, because many of the factors that influence man's susceptibility to dust are known, and can be accurately determined by competent medical methods. Among the most important factors comprising susceptibility to injury by dust are the anatomical peculiarities of the individual's respiratory mechanism, his physiological response to the inhalation of dust, his previous dust, exposure, the existence of pulmonary infections or other pathological processes in his lungs, his age,

Jan 1, 1940

By O. E. Kiessling

THIS announcement of the topics relating to production control, which the Committee hopes to have discussed at the February meeting, supplements the preliminary announcement published in the November number of MINING AND METALLURGY. In the previous article, the writer indicated the kaleide-scopic nature of the questions involved in obtaining better coordination in industry, and that, as a matter of practical expediency, the discussion in February would be limited to the more obvious difficulties in industry which need attention and to those questions which the Committee thinks would be of greatest interest to members of the Institute. But while practical considerations necessitate limiting the program, free discussion of all phases of the subject is urged by 'the Committee. In a preliminary consideration of the production control problem, there loom up two questions which have to be faced: (1) First, there is the question of the extra industrial capacity necessary to meet demand during the ordinary fluctuations of business, commonly characterized as `the "business cycle." Anyone who tries to formulate a program pertaining to productive capacity must decide whether he wishes to discuss the control of business cycles. While this question may eventually lend itself to treatment, the Committee does not feel that it can be considered at present with much profit. (2) The second question arises from the existence of over-stimulated capacity above and beyond peak demands in boom times. Discussion of this topic, it is felt, would be most fruitful. How to prevent capacity from being over-stimulated to an extent beyond any hope of possible demand is a

Jan 1, 1929

By Nelson Severinghaus

Consolidated Quarries Corp. must conduct operations for an average sales price of $1.25 per ton, about the same price at which stone was sold 25 years ago when the dollar was worth twice what it is now. To maintain success in a competitive business, the company must solve the usual production problems, which will be discussed here in the order they occur in the flowsheet. Most crushed stone quarries must first remove soil and decomposed rock. Although seasons of lower sales sometimes release regular quarry excavating and haulage equipment for this purpose, overburden is often too extensive for this method to be used. In such cases, special equipment must be assigned or the job may be contracted. As many earthmoving contractors have heavy duty specialized equipment well suited to overburden removal, they should be seriously considered before the job is undertaken. Pockets of clay beneath peaks of hard stone sometimes defy mechanized removal. Pick and shovel laborers at this point might be supplanted by more ingenious use of pumps and water or some other mechanical means. Where overburden is extremely heavy or difficult to remove, underground mining must be considered.

Mar 1, 1956

By Paul M. Tyler, Colin G. Fink

THE field of rare metals is so broad that progress can be reported upon many important fronts. Not satisfied with the 92 elements that Mendeleeff and his followers have accepted as legitimate, scientists are trying now to complicate matters by making new elements. Enrico Fermi announced the fabrication of "Element 93". Uranium, instead of being allowed to disintegrate slowly according to its normal habit, was bombarded with neutrons until some of them seemed to have stuck in the nucleus. To understand just what is alleged to have happened all one has to do is to line up the elements in their usual order of ascending atomic weight and imagine, as physicists do, that each atom is a little solar orbit comprising a central mass or planet about which other masses revolve like satellites. Ordinary hydrogen, being very light, consists of only one positively charged proton center, with only one positively charged electron revolving about it. Other atones are progressively more complicated until we come to uranium, which has a relatively big center and 92 particles revolving around it.

Jan 1, 1935

By TRUMAN S. FULLER

THE GREAT INTEREST in decomposition and trans- formation, so evident in the study of alloys during the last two years, was reflected in the many papers on this subject, presented at the first session of the Institute of Metals, Tuesday morning. Dr. F. A. Thomson, of Montana State School of Mines, presented the first paper by C. Wilson, H. F. Silliman, and E. C. Little, "Rate of Precipitation of Nickel Silicide and Cobalt Silicide in the Hardenable Copper-nickel-silicon and Copper- cobalt-silicon Alloys." Dr. R. F. Mehl, in discussing this paper, stated that the title was somewhat deceptive, as it indicated that the rate of precipitation is determined; the method used is a measurement of electrical conductivity and hardness, neither of which is suitable for a quantitative measurement of rates of reaction or precipitation in the solid state. Hardness is also uncertain because it depends so much upon particle size. Of the various methods proposed for the study of rate of reaction and precipitation the evaluation of volume of reaction produced from the area of photomicrograph is the best.

Jan 1, 1933

By AIME AIME

The Bulletin. As already announced in the January Bulletin, this publication will be issued during the coming year monthly instead of bi-monthly as heretofore. Among other reasons for this change, it is desired to effect thereby the earlier transmission to members of important papers, lists of candidates for membership, and other items of timely information. The New Haven Meeting. As already announced in special circular, the XCVIth meeting of the Institute for the reading and discussion of papers will be held at New Haven, Conn., beginning Feb. 23, 1909. The Secretary of the Local Committee is Prof. J. D. Irving, Box D, Yale Station, New Haven. The program embraces visits to many interesting works in New Haven, Ansonia, Bridgeport, etc. The leading topics for discussion at the sessions will be: The Conservation of Natural Resources; A Sea-Level Canal at Panama; and The Technical Education of Mining Engineers. But papers on other subjects also are announced. A supplementary session of this meeting will be held in New York City, at some time during March, 1909, as a joint session with other national engineering societies, for the further discussion of the subject of The Conservation of Natural Resources. A Pacific Coast Meeting. The XCVIIth meeting will be held on the Pacific Coast, including a visit to the Exposition at Seattle, and various other points en route going or coming, depending upon the route and program finally adopted. More definite information will be announced at the New Haven Meeting, or at the earliest possible date thereafter.

Feb 1, 1909

By H. W. McCue

In 1945 the number of oil wells drilled was less than in 1944 but the number of gas wells was greater. The oil wells numbered 176, completed for an initial production of 25,214 bbl., an average of 143 bbl. per well as against a total in 1944 of 245 drilled for 32,886 bbl., or 134 bbl. per well. All of these wells were in proven areas and no new discoveries

Jan 1, 1946

Ahrenholz, Herman William, Jr., Student, Lehigh Univ Bethlehem, Pa. '35 Allen, Carl A., Student, Colorado School of Mines Golden, Colo. '35 Allen, Paul W., Student, Mass. Inst. of Tech Cambridge, Mass. '35 Allen, R. M., Jr., Student, Virginia Polytechnic Inst., "G" Co Blacasburg, Va. '35 Amberger, K. H., Student, Michigan College of Min. & Tech Houghton, Mich. '35 Andersen, Burton Lee, Student, School of Mines, Univ. of Washington Seattle, Wash. '35 Anderson, Joseph S., Student, Univ. of Texas El Paso, Tex. '35 Anderson, R. C., Student, Univ. of Washington Seattle, Wash. '35 Ansel, Gerhard 627 Clyde St., Pittsburgh, Pa. '34 Anutta, Frederick P., Student, Michigan College of Min. & Tech Houghton, Mich. '35 Apsouri, Constantin N., Graduate Student, Univ. of Arizona Tucson, Ariz. '35 Arakelian, Haig Mark, Student, Mass. Inst. of Tech Cambridge, Mass. '34 Archer, George K 1420 Court Pl., Denver, Colo. '34 Argall, George O., Jr., K. E. House Golden, Colo. '35 Argiielles, Alfredo, Student, Univ. of Texas El Paso, Tex. '35 Atwater, Ralph, Student, South Dakota School of Mines Rapid City, S. D. '35 Austin, Robert B., Miner, Page Mine, Federal Min. & Smelt. CoSpokane, Wash. '34

Jan 1, 1934

By Kingman, Robert I.

SUFFICIENT testing has been .performed with the Dutch State Mines Cyclone for thickening and desliming flotation feed at the concentrator of the National Lead Co., Tahawus, N. Y., to prove its application for this work. It is the purpose of this article to present some of the test results, operational details and advantages of cyclone thickening and classification. The metallurgy of the mill operation was described by Frank R. Milliken, assistant manager of the titanium division.

Jan 1, 1950

By George F. Weaton

Although an almost continuous campaign had been carried on by various experimenters since 1885 to find a commercial process of smelting zinc by electrothermic means, no commercial success was attained in the United States. The St. Joseph Lead Co., appreciating the theoretical possibilities of such a process, such as the ability to construct units of large capacity, quality control, and the possibility of treating complex and refractory ores, decided in 1926 that the process was worthy of further investigation, and in that year, at one of its southeast Missouri plants, began the development of the electrothermic zinc-smelting process according to the invention of the late Earl C. Gaskill. Late in 1929 the process reached a stage of commercial significance, and in 1930 the erection of a modern electrothermic zinc smelter was begun, at Josephtown, Beaver County, Pa. The site is 3 miles from Monaca, which is on the main line of the Pittsburgh & Lake Erie Railroad, and a spur of the railroad has been constructed to the plant site. The site borders upon the Ohio River, which is navigable for 600 to 800-ton barges. This district was selected for the plant after an economic survey involving such questions as cost and availability of electric power, reduction fuel, transportation facilities, and the transportation charges on raw and finished materials, labor conditions, and taxes. The initial unit of the plant was designed to treat daily 120 tons of 58 per cent zinc sulphide concentrates from the company's mines in St. Lawrence County, New York. The plant equipment is housed in seven modern steel-frame buildings, and includes: Roasting and Acid Plants 3000-ton concentrate storage. Two Nichols-Herreshoff 21 ft. 6-in. diameter, 12-hearth roasters with usual cast-iron airshaft supporting chromium-alloy rabble arms and rabbles. SO2 gas purification system consisting of: One double-compartment hot-dust Cottrell precipitator. Cast-iron sinuous air-contact gas cooler.

Jan 1, 1937