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By Clarence P. Linville

It is recognized that, in all metallurgical operations, the greatest possible uniformity in all conditions is essential to the best results. It is the constant aim of metallurgists to secure this uniformity, and their success in this respect has been in many cases the cause of great advances in the metallurgical processes themselves. Of all such processes, the production of pig-iron in the modern blast-furnace is perhaps the most complex and the most difficult of control. Notwithstanding the great progress of recent years, there is still great difficulty in obtaining anything like uniform conditions and results in the manufacture of pig-iron. The reason is not far to seek. The ores vary in composition and physical properties, often carrying a varying amount of gangue material, unevenly distributed. The coke may vary in composition, cell-structure, moisture, hardness, and other properties. The blast, the weight of which far exceeds that of any other constituent, varies in its moisture-content and consequently in its chemical composition; and its temperature, by reason of the method of heating, is not uniform, but, besides varying from time to time with atmospheric and other outside conditions, has a maximum and minimum for every changing of stoves. Now, with regard to these variations, the modern demand for uniformity has been greatly aided. Chemical analysis has made it possible to select ores so that the composition of the charge can be kept fairly constant; coal may be obtained from a given field, and coked in the same kind of ovens under conditions which make the fuel practically uniform; the Gayley

Jan 1, 1911

By New kensington P. A, W. L. Fink, H. R. Freche

The investigation of aluminum alloy systems prior to 1923 was severely handicapped by the low purity of the best aluminum available. However, by that time, the electrolytic purification of aluminum had been developed by the Aluminum Company of America,(1)† and in May, 1923, there was initiated, under the direction of E. H. Dix, Jr.,(2) a program for the investigation of the aluminum-alloy systems using the purest electrolytically refined aluminum. Up to the present time 15 papers (3) have been published, most of which are on the binary aluminum systems. Work is now in progress on the ternary systems, and it seems probable that most of the future work will be on ternary systems. Therefore this survey of the binary aluminum systems investigatcd up to the present time (the sixteenth paper of the series) concludes the first phase of this program. Certain qualitative relations between corresponding portions of the various binary diagrams as well as between different parts of the same diagram were noted some time ago by R. S. Archer.(4) In the present paper these relations and others are considered quantitatively by the application of well-known thermodynamic equations or by newly discovered empirical relations. No attempt will be made here to present the history of the development of the thermodynamic equations defining equilibrium or their application to metallic systems, although a list of references is given at the end of this paper for those who are interested in this phase of the subject. Two thermodynamic equations, which will be employed extensively in this paper, are: loge x1 = - L/RT + C

Jan 1, 1934

By David J. Selleck, Eugene P. Pfleider

9.61. Introduction. Open pit mining methods produce more than 80% of all raw materials today in the United States. Much of this comes either from properties that formerly employed underground methods and were converted to open pit or from mines that ultimately must go underground when the economic stripping limit is reached. Generally the ores are transported over large vertical distances and techniques have been developed to do this economically. One approach is to combine conventional surface trucking, over relatively level roads, with the use of gravity and underground facilities. There are various modifications, depending upon the character of the orebody and the topography. Several schemes, as used in Sweden, Canada, and the United States, merit describing. One of the critical problems involved in the transference of ores from surface to underground is that of flow of bulk solids. Must it be crushed? Will it hang up in the transfer? What size and inclination of ore pass are required. How is the ore best fed onto the transporting device underground? As an example, the planning engineers for the Carol Project of the Iron Ore Company of Canada faced these problems in making their designs for the production and transportation of some 55,000 tpd from their Smallwood Mine in Labrador. Other operations, facing somewhat similar conditions, used other approaches of interest. This chapter describes some of the factors involved in the design, construction, and operation of a combination surface underground transportation system as applied to open pit mining operations. 9.62. Tunnel-Ore Pass Systems. The type, shape, dip, and size of the orebody, as well as the surface topographic features, generally estab-

Jan 1, 1968

By Frank Gilbreth

THE problem, of the crippled soldier in industry is not a problem of war work only; it is a problem of industrial development. As individuals, each one of you is seeking to provide our maimed heroes with such teaching as will render them, in the shortest possible amount of time, productive and satisfied members of the community. As individuals you are interested in the organizations that are preparing to receive these men, to train them and to place them at that work for which they are best fitted. As an organization, it is now your duty to take up the industrial end of the problem, to investigate existing conditions in the industries, to discover where the opportunities for employment lie, and so readjust industrial practice that the cripples may be utilized to their own and the community's good with the least shock to themselves or to the industries, and with the greatest amount of permanent benefit to all concerned. We have divided industrial opportunities suitable for cripples roughly, into three classes. First, such as already exist in the industries, which can be set aside for cripples only, present occupants being transferred to other work for which they can be fitted but which is not suitable for cripple work; second, opportunities in the industrial world that, through changes in the working equipment or tools, or through appliances attached to the cripple himself, can make the cripple a competitor of the sound worker; third, opportunities not existing at present in the industries, but which could be introduced for the good of the community, without placing the cripples into competition with any existing class of workers.

Jan 4, 1918

By Charles Jones

(San Francisco Meeting, September, 1915) IN any discussion of this very large subject we are confronted at the outset with so many obstacles that at best only a fragmentary and rather disconnected presentation can be made of it, and my hope is that building from the few facts I have to offer a more complete knowledge may be secured. In the whole intermountain and Pacific. Coast region, west of Pueblo, Col., and from Canada to Mexico, there is no production of pig iron, and steel production is confined to the manufacture of a small amount of open-hearth steel from scrap. When we consider the area, the resources, and the several centers of population, this condition seems anomalous, even in. the face of every counter argument as to cheap water transportation, or other means of transport from the Atlantic Seaboard or from the iron and steel centers of the Middle West. This comatose condition, if such a term may be applied, is certainly riot due to a lack of all the essential materials and factors for success in iron and steel smelting, but is rather, I think, due largely to the general fact that it is only within a comparatively few years that the centers of population on the Pacific Coast have attained a size that would entitle them to the position of distributing or freight centers, or that the "back country" has been enough built up to make it sufficiently interesting to the railroads to foster trade from the local centers to the interior points rather than seek to supply such local centers and the interior by a transcontinental haul.

Jan 9, 1915

By J. B. Ackerman, J. D. Miller

Alunite [KA13(S04)2(OH)6] is a promising non-bauxitic aluminum resource, the domestic reserves of which are estimated to be 800 x 106 tons at 35 percent alunite. The major gangue mineral associated with alunite is quartz. The thermochemical process that has been developed for treatment of this ore does not provide for the initial removal of gangue prior to processing. In this regard, it may be desirable to concentrate the ore to gain significant technical and economic advantages. Experimental results indicate the effectiveness of an oleic acid flotation technique and exemplify the problems encountered in fine particles processing. These results show that the quality of separation studied as a function of temperature, collector addition, and depressant addition is dependent on the degree of liberation achieved during size reduction. At coarse grinds the quality of separation was limited by the presence of locked particles while for finer grinds where more extensive liberation is achieved, better separations were obtained. The degree of liberation for each size interval was determined by an SEM/energy dispersive x-ray technique and found to be independent of the extent of size reduction, suggesting that liberation occurs by indiscriminate fracture and not by detachment. Up to 89 percent liberation was realized for a minus 400 mesh grind. Under these circumstances, the quality of separation appears not only to be limited by the remaining locked particles, but, also, by contamination of the alunite concentrate with fine quartz gangue (< 2µm). The best separation for the minus 400 mesh grind was a rougher recovery of 88 percent with a grade of 65% alunite at 50°C.

Jan 1, 1980

By E. van Walsum

Tunneling methods through rock have, since the successful development of explosives, relied almost solely on blasting. Over the last ten years, rock-tunneling machines (moles) have been developed and some major projects have been carried out successfully with the use of such machines, which rely on the destruction of rock by mechanical means rather than blasting. Various other basically new methods are presently under study, such as the use of laser beams, water jets, etc. For practical purposes, there are presently only two methods commercially available: 1) blasting or 2) tunneling by mole. A contractor would choose at present either one method or the other. Both methods have their advantages and disadvantages (Fig. 1). The thought has occurred that the next practical development in rock- tunneling technology might be a combination of the best features of the mole technique and those of the blasting technique. A preliminary evaluation of this approach indicated that there is definitely a good potential for fruitful developments along these lines. My purpose is to place on record some of the thinking and some of the ideas which were developed along these lines and to point out certain areas where development efforts are required. In trying to find an improved tunneling technique, we looked in particular for the following qualities: 1) safety, 2) continuity, 3) uniformity, 4) automation, and 5) flexibility. TUNNELING BY BLASTING Conventional tunneling by means of blasting proceeds generally in recurring sequences of events: 1) drilling, 2) loading, 3) firing, 4) mucking-out, and supplementary operations (such as scaling and lining). These four operations (drilling, loading, firing, mucking) proceed one after another.

Jan 1, 1970

By R. L. Templin

IN TREATING a cast metal by any working process such as rolling, drawing or forging, variations in the conditions present in the remelting, casting, chilling and preheating of the initial ingot will certainly have some effect on the physical properties of the final product. In considering the effects of cold working on the physical properties of metals, however, it will be assumed that these factors, being controlled according to best practice, will remain constant and therefore may be neglected. Starting with such a uniform metal ingot, the next operation in the production of wrought metal involves hot working by rolling, forging or extrusion so as to produce a slab, billet or bloom. This working must be sufficient to produce substantial grain refinement and minimize any defects occurring in the initial ingot. Even such a hot-worked product is not suitable as a starting material for determining the effects of cold working because it contains internal strains analogous to those resulting from cold working. It is necessary, therefore, to supplement the hot working with a considerable amount of cold working, followed by a proper annealing in order to obtain a material suitable for use in defining the effects of cold working on the physical properties of a metal. That is, if the effects of cold working are to be evaluated accurately it is necessary to have other effects at least constant if not absent. Such material, unfortunately, cannot always be obtained in commercial practice but the requirements just indicated certainly represent the desired goal; this goal has been attained in the treatment of some metals, one being aluminum.

Jan 1, 1929

By K. D. Jacob, W. L. Hill

THE bulk of natural phosphates is comprised of calcium phosphates, which are usually apatites;1 calcium aluminum phosphates such as pseudowavellite;2 and aluminum phosphates, which occur in extensive deposits, notably on Grand Connetable Island.3 Nearly all deposits of current commercial value are apatite, often with admixed material of other classes. In the trade coarsely crystalline material, mainly fluorapatite of igneous origin, moves as apatite, whereas the fine-grained material of sedimentary origin is marketed as phosphate rock. The latter classification includes the phosphate shales in western North America. Although several genetic varieties of phosphate rock are recognized,4 most known reserves are of marine origin. Calcium phosphate is concentrated from Florida land pebble and Florida hard rock deposits and from Tennessee brown rock deposits. Phosphate Rock as a Fluorine Carrier: More than two decades ago Reynolds and Jacob surveyed the fluorine content of commercial phosphate rock from various parts of the world.3,5 Later these samples were reanalyzed by a new and more reliable method of determining flourine.6,7 The revised results with interim additions of new samples, published a few years ago in a brief summary,&apos; are shown in Figs. 1-3. Through the points representing the respective varieties of rock medial straight lines are drawn. In some instances the lines are well defined by the points; in others, where scattering renders the position of the best line uncertain, the greater weight is given points near the end of the covered range. Wherever distinct varieties are not recognized among regional deposits the custom is to identify the sample with the geographical location of the deposit.

Jan 10, 1954

By E. T. Turkdogan, M. L. Pearce

The rates of sulfurization and desulfurization of calcium aluminate, silicate, and ferrite melts by CO + CO2 + SO2 mixtures at 1550°C are reported. It is shown that for melts 10 to 15 mm deep transport of sulfide ions within the melt controls the rate of sulfur transfer. The rate data from shallow melts, i.e., 1 to 4 mm deep, have been analyzed on the basis of a diffusion or a reaction controlled process and indications are that the both processes may play a part in controlling the rate of sulfur reaction. The rates of desulfurization of silicate XVEACTION equilibria between metals, metal oxides, and gases have received considerable attention in recent years. However, the understanding of and aluminate melts increase with increasing PCO2/PCO ratio in the gas stream, the effect being most marked for aluminate melts. The sulfide equilibrium data obtained from the present work are shown to be in accord with the results of previous studies. It is shown that carbon dioxide has a measurable solubility in silicate, aluminate, and ferrite melts. Consideration is given to the partial equilibria which control the directions and the rates of reactions occurring simultaneously in complex heterogeneous systems. the kinetics of heterogeneous reactions, particularly those occurring at elevated temperatures has not been improved appreciably. Almost all the metallurgical reactions occur in heterogeneous systems involving two or more phases. Although in many authoritative text books and original Papers the basic principles concerning the kinetics of heterogeneous reactions are clearly underlined, they are seldom used to the best advantage in kinetic studies, particularly those involving the metallurgical reac-

Jan 1, 1963

By Joseph T. Singewald

AMONG the genetically interesting iron ores of the United States are those of the St. Francis Mountains near Ironton and Iron Mountain, Missouri. They are specular hematite in porphyry. The Iron Mountain and Shepherd Mountain deposits are generally spoken of as veins and those of Pilot Knob, Cedar Hill, and Russell Mountain as bedded deposits. Iron Mountain has produced nearly 4,000,000 tons of ore and Pilot Knob about 1,500,000 tons. The output of the other three localities has been insignificant. Pilot Knob is no longer worked as an iron mine, but the rock is now being crushed for use as road metal. Iron Mountain has continued as an active producer. In 1927, the property was acquired by the M. A. Hanna Co. and an extensive prospecting and exploration campaign was undertaken, so that the ultimate production of Iron Mountain will doubtless greatly exceed the figures mentioned. Previous Theories of Origin Descriptions of the deposits and theories of their origin have been concerned mainly with Iron Mountain and Pilot Knob, which represent the two contrasting types of occurrence. The Iron Mountain deposits have been considered of close magmatic origin by Whitney&apos; in 18.54, Geijer2 in 1915, and Spurr3 in 1927. Whitney referred to them as of eruptive origin. Geijer considered them fissure fillings at magmatic temperatures. Spurr called them vein dikes formed from ore magma which was essentially fluid iron oxide. Schmidt4 in 1872 ascribed them to fissure filling by thermal chalybeate waters of meteoric origin. Nason5 in 1892 advanced essentially the same explanation. One of the best

Jan 1, 1929

By J. M. Gaines, C. H. Herty

IRon oxide (FeO) plays an extremely important part in the manufacture of steel. In the open-hearth furnace and the Bessemer converter it is the chemically predominant compound and controls to a large extent both the operation of the furnaces and the composition and quality of their products. Almost all of the refining action is carried out through the medium of FeO, which oxidizes carbon, manganese, silicon and phosphorus. At the end of any open-hearth or Bessemer heat the steel contains dissolved iron oxide, which must be wholly or partly eliminated. The type of deoxidation product depends on the amount of dissolved iron oxide and on the deoxidizer used. After the heat has been deoxidized and while it is being teemed, iron oxide diffuses from the ladle slag into the metal, causing losses of deoxidizer and increase in iron oxide content of the steel. It is generally believed that non-metallic inclusions are responsible for a great many failures of steel in service and for decreased yield of steel during rolling. The basis of most non-metallic inclusions is dissolved iron oxide. This investigation was undertaken in order to determine the amount of iron oxide that will dissolve in iron under various conditions. Steel-making slags are complex and it has been thought best to determine solubility under simple slags as a first step. The study is being continued under slags whose compositions approach those of operating slags Previous Investigations The solubility of oxygen in iron has been determined by a number of investigators (see Table 1) but their effort&apos;s have been directed toward the

By Sunder S. Saluja

Man had to learn to break rocks as early as the Stone Age, when they formed his main source of raw material. He started with chipping and over the years has reached a stage where he can employ atomic blasts and break, with one blast, millions of tons of rock. In between these two extremes there have been several stages of development including firesetting, use of the expansion of water on freezing in chipped cracks in cold climates, the use of low or deflagrating explosive black powder in about the 17th century, the use of high explosives with the discovery of nitroglycerine in 1846 by Sobrero, followed by the monumental discoveries of the great Swedish scientist Alfred Nobel in the latter half of the nineteenth century. The attempts to develop a stronger and still stronger explosive force were accompanied by investigations to understand the mechanism of failure of rock so that the force could be used to the best advantage; the latter, of course, have lagged far behind the former. This is mainly due to the fact that the chemical reactions involving high explosives as well as the processes resulting in the breakage of rock take place at too great a rate to be studied with the equipment that has been only recently available. Moreover, the development of stronger explosive forces was prompted by military necessities in the past and competition, at present, among highly developed nations. With the development, however, of the new techniques such as micro- second photography, microsecond flash radiography, extremely high-speed movies, strain gage assemblies, electronic chronographs and other improved electronic techniques, the investigator has in the last decade or

Jan 1, 1968

By Richard E. Chism

SAN DIMAS, in the State of Durango, Mexico, on the frontier of the State of Sinaloa, is the centre of an extensive and rich mining region, which has been exploited for over a hundred years; and the patio process for working silver ores has there attained the highest perfection of which it is capable. Local modifications have been engrafted upon the underlying principles of the process, but, as a whole, the San Dimas practice so fully illustrates its typical capabilities, that I have undertaken to describe its workings in the hope of lightening, to some degree, the labors of my professional brethren who may have occasion to visit Mexico." As is tolerably well known, the patio process, like all other systems of free amalgamation, is not successful with ores containing more than a trace of zinc or lead, the presence of zincblende being especially obnoxious. Iron and copper in small quantities are not particularly disadvantageous. The process succeeds very well with all sulphide ores which do not contain much more than a trace of arsenic and antimony, provided the tailings are concentrated, although, of course, it is best adapted for free milling ores. For suitable silver ores that contain small amounts of free gold the process is still a good one, but where the gold is combined with sulphurets, a considerable and even an excessive loss is inevitable. Hitherto the Mexicans have submitted to this loss, but, since the introduction of American mills, they are gradually abandoning the patio process in favor of the other. The San Dimas ores have a gangue of quartz and feldspar. They are composed principally of silver sulphides, with some chloride and

Jan 1, 1883

By R. F. Slack, J. C. Draper, J. A. Younkins

In 1959, the Duquesne Light Co. was faced with the problem of moving more than 40 million tons of bituminous coal in Greene County, Pa. The coal had to travel a distance of about 4 ½ miles from a new mine portal in Rocky Run Valley to the company preparation plant and loading facilities on the Monongahela River. After careful study of this immense transport problem, Duquesne decided that the belt conveyor system described in the following pages offered the best solution. This system, now in operation, is probably one of the four or five longest permanent overland conveyor systems in existence. The general layout of the entire system is shown in Fig. I. A detailed description of the salient features of the system is presented below. THE MINE The valley of Rocky Run where the system begins is very, very narrow and very steep. It was chosen as the site of Duquesne&apos;s new mine portal because it was the only place on this particular property where the Sewickley coal seam cropped out. The valley also had two other advantages. First, it fronted on a state road and, second, it offered a site where some 4 million gallons of water could be stored for use in dust-allaying sprays needed in the mine. The company elected to construct a drift mine in the valley because this would require neither the hoisting time of a shaft mine nor the walking time of a slope mine. As part of the mine construction project, the valley was leveled by relocating its stream and filling its center with material cut from each side.

Jan 11, 1966

By A. W. Ambrose

THE underground losses of oil exceed by hundreds of thousands of barrels all the oil that has been lost in storage, transportation, or refining. The quantity lost is, of course, indeterminate; but when it is considered that the contents of an entire oil field have been excluded from recovery by invading waters, some idea of the amount wasted may be gained. Similarly, enormous quantities of gas have been lost underground. Conservation of the oil, therefore, should start before it is brought to the surface rather than after it is placed in storage tanks. Water is one of the most important causes for underground losses and the operator should give as serious consideration to an underground flood of water as he would to a destructive surface flood. The best insurance, of course, is to have the wells drilled in such a manner that water has no access to the productive oil and gas horizons, and on abandonment the wells should be properly plugged. The encroachment of edge water and the occurrence of water in the base of an oil sand present a very serious problem to an oil company; sooner or later these waters are bound to cause considerable damage, if they do not entirely destroy the possibilities of further production. Too often, however, a field has been considered to be in a hopeless condition, whereas wells in as bad a condition in other areas have been repaired and the life of the field appreciably lengthened. The corrections are very often suggested by technical study. Very successful results have been accomplished by detailed underground work in the California oil fields, in Cushing, Oklahoma, and in other areas.

Jan 9, 1920

L. D. Ricketts, New York, N. Y.-In recent years the metallurgical field of the copper industry has expanded greatly, the copper ores have become lean and diverse in character, and we are obliged to treat such ores on a very large scale. On the commercial side, the operating and consulting staffs of ,the great mining companies have been enlarged and organized, and no great capital expenditure is decided upon until it has been investigated and recommended by a highly organized force of specialists as a committee. I believe that in the scientific field and in the most valuable proceedings of our various societies the old idea of one-man point of view and one-man treatment of principle and detail together has been. splendidly developed and should continue, but for the advancement of our art we should deliberately discuss subjects among ourselves in order to do away with the idiosyncrasies of the individual and to gain a composite view representing the best thought of many men. In the development of new ideas leading to the introduction of new methods, the societies could enlarge their present great field of usefulness if such discussion be had, and in my opinion further great good could be done if a number of men of different qualifications and experience would join in preparing a joint book, each dealing with his particular problem, but consulting the other men. In this way individualism would be preserved and various processes would be described, and if properly reviewed the paper would be palpably capable of analysis, and the student would have at his command the associated efforts of a group of qualified engineers.

Jan 4, 1915

By John L. Schroder

In selecting the best system of mining for a particular operation, many different factors must be considered. The system to be finally selected should be that which provides: 1) The highest possible degree of safety for mine personnel. 2) The lowest cost per ton of product. 3) The maximum coal production per man-shift. 4) The most suitable quality of final product, considering its intended use. 5) The maximum percent recovery of coal per acre of reserve consistent with cost and subsidence rights. 6) Consideration for the ecology of the area. Some of the important factors to be considered when choosing a method of mining are: 1) Amount of cover over the coal seam. 2) Type of the rock in the overburden. 3) Characteristics of the coal seam including: (a) the thickness of the coal seam; (b) the nature and location of any impurities or irregularities; (e) the dip (or pitch) of the coal seam; (d) the nature and direction of any definite cleavage ill the czoa1 seam; (e) the hardness of the coal; (f) the structural strength of the coal; and (g) the presence, anti amount, of explosive gas (methane). 4) Quantity of water likely to be encountered in the mining operation. 5) Nature and strength of the roof (top) over the coal seam. 6) Nature and strength of the floor (bottom) under the coal seam. 7) Any previous or concurrent mining in seams above or below the coal seam to be worked. Information on items 1-7 may be obtained in several ways. Topographical and geological reports and maps of the area are generally available

Jan 1, 1973

By H. D. Hoskold

It was not for the purpose of asserting any superior knowledge or authority, but simply of clearing up, in greater detail, some points casually mentioned in Mr. Scott&apos;s able paper, that the writer entered, some two years ago, into the discussion which that paper initiated. In such matters there is always room for differences of judgment, as well as for additional data, which may modify or complete the conclusions even of the best authorities. Those who are immersed in the duties of practical administration or work in the field, and who, being remote from the great scientific national libraries, are obliged to rely on their private collections, and to supplement them by their recollections of earlier studies, labor under special disadvantages in such a discussion; and it must be to the scientific and engineering world a matter for gratitude that Mr. Lyman has been willing to give the benefit of his advantages in this respect. Mr. Lyman would, however, doubtless at once disclaim the conclusion that his masterly summary constitutes " the last word " on this subject, and welcome further evidence, comment and criticism, such as the various contributors may continue to offer. This, therefore, is the motive, and must be the excuse, of the introduction by the writer of the following observations. The Miners&apos; Dial.—Many years since, the writer employed a miners&apos; dial, older in type than Fig. 12,* but without any attached spirit-level, made by Thomas Jones, a pupil of the great Ramsden. Jones was one of the old London makers and opticians, and enjoyed great reputation for accuracy in the con-

Jan 1, 1902

No phase of the steel industry is more typical of its remark- able progress than is the evolution and development of the modern American blast furnace. The founding of the Institute in 1871 also marked the beginning of a new era in the pig-iron industry. The rapidly expanding westward development of the country, with its seemingly unlimited markets, gave rise to unprecedented demands for blast-furnace products. The manner in which the iron industry responded provides a fascinating chapter in the history of industrial development. Prior to this period, the iron industry of the United States, largely concentrated in the East, was based upon the consumption of local iron ores and local fuels, the latter predominately charcoal and anthracite. Small, isolated furnaces were located near scattered ore and fuel sources, and the completely integrated ironworks and steelworks were yet to be developed. In about 1860 exploitation of the newly discovered rich ore deposits in Michigan and the successful adaptation of blast furnaces to coke produced from coal of the great Pittsburgh seam in western Pennsylvania proved to be major factors in firmly establishing the general westward shift of the industry. But these were largely economic in character, and it was not until about 1870 that the aggressive, individualistic nature of the ironmaster asserted itself in no uncertain manner. No longer limited by relatively inadequate equipment and inferior raw materials, and spurred as well as encouraged by those who supplied capital for these new enterprises, furnacemen began to establish unheard of records in iron production. It is not surprising that Pittsburgh was the center of this new activity. Its tenor is best indicated by the following account :l

Jan 1, 1948