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By Douglas Bunting

(Wilkes-Barre Meeting, June, 1911.) WITH the gradual exhaustion of the upper veins in the anthracite coal-fields, the problem of mining at greater depths acquires increasing importance and demands the consideration of a number of important factors, one of which is the greater earth-pressure and the consequent necessity of stronger support o for the roof. Under the pillar-and-chamber system, almost exclusively followed in the Northern anthracite-field, the highest economy in mining is generally secured by leaving, on first mining, pillars only sufficient to support safely the overlying strata. As to the necessary size of such pillars, the opinions of mining experts are widely divergent. In establishing the width of chambers and pillars, the thickness of vein and its depth below the surface have received little consideration. For. instance, it has been quite usual to work both overlying and underlying veins with the same width of chambers and pillars, when the lower vein was two and one-half times as thick, and twice as fits below the surface, as the upper. In view of the generally-accepted theory that the crushing-strength of coal-pillars of the same base-area becomes less with increased height, it is probable, in this instance at least, that the most economical mining has not been secured. This question of adequate pillar-support is economically less important down to about 800 ft. than at greater depths; and it is with reference to mining at these greater depths that the study of the subject here presented has been prompted. The necessity of leaving larger pillars, involving greater mining-costs per ton and also smaller yields per acre, is one of the troubles of deep working. To mine without leaving adequate pillar-supports will result, sooner or later, in a squeeze. Limited areas, it is true, have been mined at certain widths of

Sep 1, 1911

By A. L. Holley

THIS process is performed in the Pernot puddling furnace; it removes from 75 to 80 per cent. of the phosphorus, most of the sulphur, and practically all the silicon, from crude iron, in from five to eight minutes. It has been in regular use since March, 1877, and has prod uced over seventeen thousand tons of washed metal for the open-hearth furnace. During two years, nearly all, and lately, all the open-hearth steel produced in these works has been made from about 5 tons of washed pig and 2 tons of scrap per open-hearth furnace heat. There are 12 open-hearth furnaces, of which 4 to 9 are running, according to the state of orders. A large amount of highly phosphoric iron from France and Belgium has been also washed and then puddled for parties who have taken, or are expected to take, licenses. The washing of pig for puddling, however, is not a practice at Krupp's works, because pure pigs are nearly as cheap as impure ones. The author and his assistant, Mr. Laureau, spent, during the last month, three days at Krupp's works, examining this process. They copied out of the office books characteristic analyses and physical tests, some of which are given herewith. They also brought hone many samples of pig, cleaned metal, puddle bar, and steel, which they saw treated. Analyses of some of these samples appear in Table IV. As there are no blast furnaces at Essen, the iron is melted in two Bessemer cupolas with fore-hearths; they melt 12g pounds of iron with 1 pound of coke. The metal is run by a spout from the fore-hearth into an opening at the side of the main door of the washing-furnace. The Washing furnace.-This is a regenerative gas furnace. It has a Pernot revolving-hearth of 12 feet external diameter and 3 feet depth. (See Plate.) The four regenerator chambers have 780 cubic feet capacity, which is about the same as the average regenerator capacity of open-hearth steel furnaces of equal tonnage. The lining is 13 inches thick on the sides and 9 inches on the bottom, thus giving a hearth 9 feet 10 inches by 2 feet 3 inches deep. The lining is composed of lumps of highly refractory ores

Jan 1, 1880

By A. L. Holley

This process is performed in the Pernot puddling furnace; it removes from 75 to 80 pel. cent. of the phosphorus, most of the sulphur, and practically all the silicon, from crude iron, in from five to eight minutes. It has been in regular use since March, 1877, and has produced over seventeen thousand tons of mashed metal for the openhearth furnace. During two years, nearly all, and lately, all the open-hearth steel produced in these works has been made from about 5 tons of washed pig and 2 tons of scrap per open-hearth furnace heat. There arc 12 open-hearth furnaces, of which 4 to 9 are running, according to the state of orders. A large amount of highly phosphoric iron from France and Belgium has been also washed and then puddled for parties who have taken, or are expected to take, licenses. The mashing of pig for puddling, however, is not a practice at Krupp's works, because pore pigs are nearly as cheap as impure ones. The author and his assistant, Mr. Laureau, spent, during the last month, three days at Krupp's works, examining this process. They copied out of the office books characteristic analyses and physical tests, some of which are given berewith. They also brought home many samples of pig, cleaned metal, puddle bar, and steel, which they saw treated. Analyses of some of these samples appear in Table IV. As there are no blast furnaces at Essen, the iron is melted in two Bessemer cupolas with fore-hearths; they melt 124 pounds of iron with 1 pound of coke. The metal is run by a spout from the forehearth into an opening at the side of the main door of the washingfurnace. The The washing-furnace.—This is a regenerative gas furnace. It has a Pernot revolving-hearth of 12 feet external diameter and 3 feet depth. (See Plate.) The four regenerator chambers hare 780 cubic feet capacity, which is about the same as the average regenerator capacity of open-hearth steel furnaces of equal tonnage. The lining is 13 inches thick on the sides and 9 inches on the bottom, thus giving a hearth 9 feet 10 inches by 2 feet 3 inches deep. The lining is composed of lumps of highly refractory ores

Jan 1, 1880

By Jay F. Smith

The Alan Wood BOF Shop consists of two 140 ton furnaces with a rated yearly capacity of 1-1/4 million ingot tons, he hot metal for the BOF Shop is supplied by two 18 foot blast furnaces which produce an average of 2000 tons per day, To achieve the rated ingot ton capacity with this limited supply of hot metal, the preheating of scrap is necessary. This is accomplished in the furnace by using an oxygen-natural gas burner. Piping Arrangement The natural gas and oxygen are piped into the Shop through 8-inch lines to their respective valving stations. As can be seen from Figure 1, the flow of natural gas passes through a flow control valve which is common to both furnaces, after which it divides into two 6-inch lines forming two identical and independent gas control lines, one for each furnace.

Jan 1, 1972

By George Krauss, M. Cohen

The reverse martensitic transfomzation (i.e., the conversion of martensite to austenite on heating) was investigated in Fe-Ni alloys containing 30.5 to 33.5 wt pct Ni. The reversed austenite was found to be sufficiently distorted to exhibit marked differences in mechanical properties and to undergo recovery and re crystallization on further heating. In particular, the yield strength of the reversed austenite was as much as 2.5 times higher than that of the virgin austenite: with five cycles of the direct and reverse martensitic transformation, the yield strength was 2.6 times higher. There was an accompanying decrease in strain-hardening capacity and in stable ductility or uniform elongation. The recrystallization was observed to follow sigmoidal kinetics, but was characterized by an abnormal1y large temperature dependence which was evidently due to carbon segregation at the migrating grain boundaries. Upon recrystallization, the strength Properties reverted to those of the virgin austenite, but the ductility did not fully recover until the annealing temperature was further raised to dissipate the carbon segregation at the grain boundaries. The transformation of reversed austenite to produce second-generation martensite resulted in an unusually imperfect structure, thereby leaditg to additional strengthening. Horlleuer, the martensitic phase was much less responsive in this respect than was the austenite. MOST martensitic transformations are capable of undergoing a reverse transformation back to the austenitic phase on heating.&apos; This reaction, like the direct transformation to martensite on cooling, is usually athermal. In analogy with the Ms andMf temperatures for the martensitic transformation (where M, > Mf), the reverse transformation is characterized by the As andAf temperatures (where As<Af). It is well-known that the finish (Af) of the martensite-to-austenite reaction on heating may occur at a temperature where austenite is not stable relative to other phases in the equilibrium diagram.&apos; Reverse martensitic transformations have been found to influence the properties of the parent austenitic phase in a number of ferrous alloys. The austenite thus produced after one or more reversals is significantly altered in strength, microstruc-ture, diffusivity, and annealing characteristics compared to well-annealed, virgin austenite. The first detailed observations of such phenomena were made by Wasserman3 on an Fe-30 wt pct alloy. He found that the reversed austenite (i.e., austenite formed by the reverse martensitic transformation) was much stronger than the original austenite, and the second-generation martensite (i.e., martensite produced from the reversed austenite) was somewhat stronger than the first-generation martensite. On heating the reversed austenite, recrystallization occurred in a manner similar to that of a cold-worked metal; the Laue spots sharpened and the strength decreased.4 In recent years, Russian workers have shown considerable interest in these reverse martensitic transformations. Most of such investigations5-10 have been concerned with the stabilization of reversed austenite relative to subsequent martensitic transformation, and because of its unusual nature, this phenomenon will be discussed in detail elsewhere." On the other hand, the annealing behavior of reversed austenite and the attendant variation in properties have received little attention beyond the experiments of Wasserman.3,4 Gridnev eta1.,8 in one of the few such studies. followed the hardness change of reversed austenite as a function of time at three annealing temperatures. The marked strengthening of austenite achieved by the reverse martensitic transformation has been referred to as "transformation strengthening" by Wasserman3,4 and as "phase hardening" by Malyshev et a1.7,9,10 to differentiate it from hardening produced by cold working. Both groups of investigators noted that further strengthening of the austenite could be attained by repeated or cyclic transformations, but the first cycle resulted in the most pronounced effect. Evidence of the altered microstructure of reversed austenite has been reported by Maximova and Nikonorova6 and by Edmonson and KO.12 The former found that reversed austenite was much more sensitive to etching than the original austenite, and the latter authors observed a (&apos;ghost" structure resembling martensite in certain areas of the reversed austenite. Enhancement of the self-diffusion rate in reversed

Jan 1, 1962

By T. R. A. Davey

A Survey of current and recent research and developmental work is supplemented by predictions for processes which should be developed over the reminder of this century.

Jan 1, 1970

By Charles Will Wright

THOSE that attended the seventeenth International Geological Congress held in Russia last summer had an excellent opportunity to gather data and to form impressions on the progress made in the industrialization of the country, particularly with regard to the mineral industries. Several trips to places of interest were arranged, supplementary to the technical sessions held in Moscow, the one to the Ural region being that which I selected as being most likely to be of interest. The accomplishments of the last decade in opening up new mines and building new metallurgical plants in the Soviet Union have been outstanding. This could only be accomplished by a central government ready to employ the best technical talent, which was

Jan 1, 1937

By R. G. Hite, R. G. Rowe

The Crandon deposit, located in northern Wisconsin, is a 65.8 million ton Precambrian volcanogenic massive sulfide deposit which averages 1.4% copper and 5.8% zinc. The deposit is classic in origin, mineralogy and shape. Comprehensive understanding of the geology of both the deposit and the project site has been fundamental to the credibility and success of project feasibility studies and regulatory permit preparation. Mine development in the current investment and regulatory climate requires thorough and timely application of geologic tools. From 1977-1980 geologic activities were focused on the typical objectives of orebody delineation, reserve estimation, depositional geology, and general site investigation. Results from these programs formed the basis for the project&apos;s preliminary feasibility studies. Since 1981 further geologic investigations have provided criteria for project design, site management, and operational permitting. Activities have included mine entry position definition drilling, developing geostatistical reserve modeling, large diameter (150 mm) core drilling for mill pilot samples, rock mechanics testing, and evaluation of the glacial overburden/deposit geohydrology for computer simulation.

Jan 1, 1984

By Robert E. Sorenson

EXPLORATION for deep-seated orebodies in the Silver Belt area of the Coeur d&apos;Alene mining district is complicated by meager surface expressions of diagnostic criteria, lack of knowledge of the significance of specific alteration phenomena, and the great expense involved in the exploration for ore shoots, the tops of which often occur near sea level elevation or below and as much as 4000 ft or more below the surface. Except for the early studies of Ransome and Calkins in 1903 and 1904,[1] little geological work was done in the Coeur d&apos;Alene district for many years, and it is only during the last 15 to 20 years that complete and careful geological mapping has been applied to most of the mines in the area. Much early information, which now would prove invaluable, is lost in hundreds of miles of caved and inaccessible mine openings not mapped by mining geologists. In more recent years mining geology has become a tool of greater use in the district, and some measurable progress is being made in the accumulation of observations that are adding gradually to the knowledge of ore deposits in the district.

Jan 7, 1951

By B. A. Stainton, John D. Gill

OUR combined economic activities have as their goal the maximum of individual well-being and national security. In this age of intense international competition the two objectives are closely related. For many decades, the maximum of well-being and ability to maintain national security have moved generally upward. The best single measure-perhaps the only adequate measure -of the level of the rising goal is the per capita real national income (national income corrected for price changes). For centuries before the industrial revolution the income of the world&apos;s population changed little from generation to generation. In our country prior to 1800 the growth of national income was hardly measurable from decade to decade. Since 1850, perhaps since the "industrial revolution," the growth of per capita real income has been increasing geometrically. Of major importance is the accelerative growth of the productive ability of our economy. Inadequate consideration of its implications is partly responsible for periodic delays in solving our princi-

Jan 1, 1946

By Sherwin F. Kelly

PLAIN mining engineers usually avoid any gathering of geo¬physicists because of the incomprehensibility of their discussion to the uninitiated. This being so, gradients, gravity and gammas will be deferred to the end of this review, the first part of which will be devoted to what has been done in applying geophysics to the solution of real field problems. From the West, J. J. Jakosky reports that International Geophysics has had its activities fairly well &apos;divided between mining (both placer and lode), oil structural work, and clans-site and reservoir investigations. In oil exploration, electrical methods are used for depths down to 2500 ft., beyond which they utilize seismic methods. They find in their placer work that the many &apos;magnetic anomalies encountered in the bedrock of the Southwest render the electrical techniques more satisfactory, and with them they are obtaining thickness and tonnage of gravels, depth to and contour of the underlying bedrock as well as important structural features therein, and water-table elevations.

Jan 1, 1934

By Harlowe Hardinge

[Crushing Tests by Pressure and Impact (T.P. 1895, by F. C. BOND,, Min. Tech. Jan. 1946). Discussion by H. HARDINGE and the author 1 Pumping Sands, Slurries and Slimes and Installation and Performance of Sand Pumps (T.P. 2013, by W. B. STEPHENSON, Min. Tech., May 1946 and T.P. 1978, by C. G. SOUTHMAYD, Min. Tech., March 1946). Discussion by OSCAR LEE, G. J. HOLT, L. D. ANDERSON, and the author 2 Rapid Polarographic Method for Determination of Copper, Zinc and Lead in Flotation Tailings (T.P. 2010, by G. A. CROWE and W. T. BISHOP, Min. Tech., March 1946). Discussion by E. H. ROSE and the authors 4 Ball Wear and Functioning of the Ball Load in a Fine-grinding Ball Mill (T.P. 1984, by W. I. GARMS and J. L. STEVENS, Min. Tech., March 1946). Discussion by J. F. MYERS, E. W. DAVIS, F. M. JARDINE, H. HARDINGE, F. C. BOND and the authors 5 Correlation between Mineral Behavior in Cataphoresis and Flotation (T.P. 2005, by A. M. GAUDIN and S. C. SuN, Min. Tech., May 1946). Discussion by 0. C. RALSTON, G. L. SIMARD and D. J. SALLEY 7 Accident Experience in Milling (T.P. 1981, by J. F. MYERS and S. E. SHARP, Min. Tech., May 1946). Discussion by C. E. MCKNIGHT, C. H. BENEDICT, T. S. WILSON and S. POWER WARREN9 Mill Design for Labor Economy (T.P. 1997, by NORMAN WEISS, Min. Tech., May 1946). Discussion by R. S. HANDY and the author13] Crushing Tests by Pressure and Impact (0.C. Ralston presiding) HARLOWE HARDINGE.*-Has the impact method described in the paper been used to compare the resistance to reduction in size of various materials with actual operation results of mills in the field? Is this impact method a better index of the true resistance to grinding under actual field conditions than other methods the author has reported in the TRANSACTIONS? F. C. BOND (author&apos;s reply).-The impact crushing device was designed to measure relative resistance to crushing, or what may be called the crushability, and is not used for comparing the resistance to grinding, or grindability. The correlation between crushability and grindability of different materials is not at all close, since fractures, zones of weakness, and structural features of rock have a much greater effect upon the crushability than upon the grindability. We still depend upon our standard grindability tests for measuring resistance to grinding, and use the impact crushing tests only in relation to crusher installations. The impact crushing device has several advantages over the measurement of crushing strength in pounds per square inch as an index of crushing resistance.

Jan 1, 1946

By Willard L. Cumings, Benjamin L. Miller

(Glen Summit Meeting, June, 1911.) I. THE CAMAGUEY DEPOSITS. 1. Location. THE Camaguey brown iron-ore deposit covers the top of San Felipe hill, the nearest point of which lies 14 miles NW. of the city of Camaguey. While there are several low flat-topped hills in the vicinity covered with a more or less continuous mantle of brown iron-ore, the deposit of San Felipe hill is the only one of any size and importance, and the name "San Felipe district " is proposed for the region. The deposit extends in a NW-SE. direction for a distance of about 10 miles, with an average width of 5 miles. The location is shown in Fig. 1, a sketch-map of the eastern part of Cuba. Fig. 2 is a map of the San Felipe district. 2. Description. The district is mentioned by Spencer,1 who says: "The Cubitas iron-ore fields are situated from 12 to 15 miles north of Camaguey City, in the province of Camaguey Within an area measuring roughly 10 miles east and west and 4 miles north and south, there are several flat-topped mesas rising 300 to 400 ft. above the level of an almost featureless plain which extends for many miles in all directions except toward the north." With the exception of the discrepancy in his statements as to the distance from Camaguey and the area of the hill, which is over 50 sq. miles, his description is a very good one. Kemp 2 has the following to say of ores in Carnaguey Province * Geologist, Bethlehem Steel Co. + Professor of Geology, Lehigh University. 1 Bulletin No. 540, U. S. Geological Survey, p. 324 (1908). 2 The Iron Ore Resources of the World, printed by the Eleventh International Geological Congress, vol. ii., p. 795 (1910).

Mar 1, 1911

By F. H. Deily, D. S. Rowley, R. J. Howe

By A. J. Opinsky

THE purpose of this note is to indicate the locations and sizes of various interstitial holes in the orthorhombic uranium lattice based on a hard-sphere model. First, plane configurations of three and four atoms will be examined, and then the true interstices surrounded by four atoms in space and by five atoms in space will be obtained. The data and notation contained in a report by Tucker&apos; will be used. Plane Configurations Fig. 1 presents the orthorhombic uranium lattice made of spheres touching at the closest interatomic distance. The three light-colored spheres in the ab plane are illustrative of the first type of configuration to be examined. If one edge of the unit cell is taken as the origin, the three atoms can be represented by the vectors [Oi + Oj + Ok], [ai + Oj + Ok] and [(a/2)i + (b/2)j + Ok] where i, j, and k are respectively parallel to a, b, and c. In the future, this notation will be shortened to [000], [a00] and [a/2 b/2 0], respectively. A vector R = [r s t] de-scribes the position of the hole surrounded by the atoms. Since the center of the hole must be equidistant from the three atoms R2 = r2 + s2 + t2 = (r-a)2 + s2 + t2 = (r-a/2)2 + (s-b/2)2 + t2. R = [a/2 (b/4) - (a2/4b) 0] is the solution of these

Jan 1, 1955

By Cecil H. Desch

THE progress of metallurgical practice and the demands made by the engineering industry on our foundries and mills have made the crystalline structure of metals a subject of far more than academic interest. Metals and alloys are made up of crystals. Even if we accept the view, so ably maintained by some metallurgists, that the crystals are separated from one another by an amorphous layer, it remains true that all but a very minute fraction of any metallic mass is crystalline. The conditions which affect the growth of crystals are therefore of importance in metallurgy. It is not only castings whose properties depend on the arrangement of their crystals, for the more we learn of the behavior of forged, rolled and drawn metals, the more certain it becomes that it is profoundly influenced by the size and arrangement of the crystals in the original ingot, deter- mining a structure which may persist in a modified form through a long series of mechanical operations and annealings. This is mainly due to the concentration of much of the impurities in the last portions of the liquid to freeze, so that the boundaries between single crystals or groups of crystals are marked out by a zone of segregated material, differing in properties from the mass, and offering a barrier to diffusion and equalization of composition throughout the whole. The importance of this fact has been fully recognized by steel manufacturers, who have to deal with ingots which are sometimes very large, and are cast at a high temperature, containing impurities which have a marked effect on the properties even when present in very small quantity. For this reason the Iron and Steel Institute has set up a committee to examine the whole question of the heterogeneity of steel ingots,(l)f and a report has been issued, containing an account of the structure of 16 ingots, ranging in weight from 15 cwt. to 172 tons, each of which was sectioned and examined by chemical analysis and by etching. A valuable body of data concerning segregation has thus been collected. The work of the committee is being prosecuted with great activity, and at the same time researches are in progress to determine the physical

Jan 1, 1927

By Thomas T., Read

IT is difficult to judge how much influence the success attained during its first year, 1864-65, by the School of Mines at Columbia had on developments in education for the mineral industry elsewhere in the immediately subsequent years. The facts are as follows: 1. The Massachusetts Institute of Technology began giving instruction in February 1865, with a mining course included in its curriculum. 2. Early in 1865 the faculty of the Department of Science, Literature and the Arts of the University of Michigan requested permission from the Regents to establish "a course of study to be called the School of Mines . . . Also that the degree of Mining Engineering, be conferred on students who should complete the course of study prescribed in the same." A resolution authorizing this was adopted by the Regents on March 28, 1865. 3. Samuel Hooper endowed a Sturgis-Hooper professorship of geology at Harvard in 1865 with the intention of making it a nucleus of a new School of Practical Mining and Geology. 4. Yale appointed Alfred P. Rockwell professor of mining in 1865. 5. Lafayette College appointed Henry S. Osborn professor of mining and metallurgy in 1865. 6. Washington College (as Washington and Lee was then known), rising out of the ashes of Civil War destruction, made a fresh start in 1865, with Generalized as its president, and offered a mining course in the first catalogue thereafter published. 7. Lehigh University, founded in 1866, had a mining curriculum from its beginning. 8. Rensselaer Polytechnic began offering a curriculum in mining and metallurgical engineering in 1867. It would be natural to suppose that these events were a reaction, to the success of the school at Columbia, - and possibly they

Jan 1, 1941

By ALBERT P. J. BORDEAUX

THIS paper briefly describes the general outline of cyaniding silver-ores in Mexico, with special reference to personal experiments made in the Temascaltepec district. The most important papers on the subject deal with cyaniding gold-silver-ores, the gold predominating in value, so that the treatment is nearly the same as for gold-ores, the losses of silver being considered of little importance. I describe here the treatment of silver-gold-ores containing very little gold, which is more general in Mexico than elsewhere. The cyanide treatment, which was so successfully applied to gold-ores, did not succeed immediately with silver-ores on account of their varying composition. Gold occurs in nature usually in the native state, while silver occurs generally in combination with sulphur (argentite), and various combinations of sulphur, antimony, and arsenic. In former times there was a complete difference in the treatment of gold-ores and silver-ores. Amalgamation, which was successful with gold-ores, was generally inadequate with silver-ores. The usual treatment in Mexico for silver was the patio process, the theory of which was satisfactorily explained only quite recently by Mr. Ortega and others. GENERAL OUTLINE OP THE CYANIDE TREATMENT. The general tendency of the present practice is to slime the silver-ore as much as possible, and in order to obtain a higher efficiency, with less loss of cyanide, and greater speed, the following lines are observed 1. Crushing by stamps with 30- or 40-mesh screens, then crushing by Huntington or Chilean mills, through 60- or 80-mesh screens. 2. Concentration upon vanners.

Jan 1, 1910

By H. G. Schneider

THE Smackover oil and gas field lies in Ouachita and Union Counties, Ark., in the south-central part of the state, in T.15 and 16S., R.15, 16, and 17W. It is 10 miles north of El Dorado, the principal business and railroad center in the south-central part of the state, and extends from the town of Smackover in all directions. Productive territory having an aggregate area of nearly 55 sq. mi. has been developed. It extends 6 miles from north to south and 12 miles from east to west. The field may be divided into two parts: the east district, which includes the area east of the town of Smackover, and the west district, which includes the area west of the town of Smackover. In relation to the neighboring productive fields of Arkansas, the Smackover field is 9 miles north of .the El Dorado oil and gas field, 8 miles slightly west of north of the East El Dorado oil and gas field, and 16 miles east of the Stephens oil field. Smackover was discovered in May, 1922, when the Oil Operators Trust drilled well No. 1 on the J. T. Murphy farm, in the southeast quarter of sec. 8, T. 16S., R.15W. This well is located almost, on the top of the Norphlet dome and was drilled to the Nacatoch sand. It had an initial open flow volume of 30,000,000 cu. ft. of dry gas per day, and a rock pressure of 950 lb. per sq. in. In July, 1922, the V. K. F. Co. completed the first oil well in sec. 29, T.15S., R.15W., on the north side of the Norphlet dome, and 3 miles north of the first gas well. This well started the active development of the north and northwest sides of the dome.1

Jan 3, 1924

By E. D. Gardner

AGAIN in 1945, the fourth year of World War 11, the American mining industry met the necessary demand made upon it for metals. Lack of labor prevented full production in some districts; maximum output, however, was maintained with the man power available. Development work and maintenance of mechanical equipment were neglected in favor of immediate production. Drafting of the younger men continued throughout the year, and the loss of personnel to war industries with higher wage rates continued up to "V-J" Day, Aug. 14. Labor shortages were more critical in 1945 than in 1944 though the man-power situation eased for some districts in the last quarter of the year. The trend in mining for the most part was to increase tons per man-shift by continued increased mechanization and refinements in methods and practices; larger equipment was installed where practicable. Labor shortages, together with the current higher wage rates, have advanced mechanization several years ahead of normal progress. The manpower shortage and the employment of inexperienced men had the effect of decreasing the average efficiency of the individual workman, but this condition was largely balanced by improved organization, greater efforts to improve labor relationship, and increased use of incentive pay systems. Safety instruction was emphasized, personnel contacts were increased, and more frequent foremen meetings were held to clarify contract agreements. Many of the large companies maintained schools to train green workmen.

Jan 1, 1946