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By Blandford C. Burgess

Mica is an orchid among minerals. It is formed in pegmatites, one of the most bizarre of igneous formations, and is exceeded by few other minerals in the perfection it may attain as to size, color, and cleavage. First used for window glazing, as an ornament and article of trade, it has become one of the most essential insulators of electricity, heat, and shock. Most internal combustion engines use mica condensers or capacitors and such machines of war as planes, tanks, and submarines are immobile without it. The original manuscript of this guide was written in April 1943 at the peak of war emergency. It was not used be- cause shortly thereafter a decision was made to buy on a one price basis eliminating differentials for both quality and size. This is now presented with the thought that from the standpoint of preparedness we can only consider an- other war imminent and every effort should he made to set up in usable form the experience gained during the Second World War. Colonial Mica Corp. was set up by Metals Reserve Co. as a wholly owned government agency to encourage production of domestic mica and to purchase it. It soon became the exclusive buying agency for such mica. The writer as Southern Manager called on all the private agencies buying mica to assist in formulating buying policies, methods, and prices.

Jan 1, 1949

By Sherwin F. Kelly

THE present lull in engineering activities presents an advantageous moment for inquiring into the position now occupied by geophysics in its various fields of application. The recent over-expansion in all lines of work resulted in an uncritical employment of these methods of exploration which was bound to have its harmful reaction. The pendulum has now swung back, producing a decidedly hypercritical attitude toward the new science that had been recently welcomed so joyfully as the panacea for prospecting troubles. The severe retrenchment in exploration has forced upon us a period of waiting and, it is to be hoped, of profitable contemplation. This can well be employed in trying to pass a reasoned judgment on what position geophysics should occupy in the new geological exploration programs that will inevitably ac- company the looked-for industrial recovery.

Jan 1, 1931

By R. D. Parks

DESPITE the handicap of reduced production in many districts, the mining industry in 1938 forged steadily ahead toward solution of its minor technical problems and has of-defected major advances in several fields. In California hydraulic mining for gold, shut down for forty years, will shortly be resumed following revision of restrictive laws. Disposal of hydraulicked ground is to be regulated by settling dams so as not to interfere with agriculture. Gold mining has been aided also by the development of a new high-efficiency dry amalgamator which applies the Ramsay mercury separator to the original de Phily process. Based on the principle that crushed ore will follow a rod into a mercury bath, this simple device is primarily adapted to dry areas and is to be available in small, multiple units suitable

Jan 1, 1939

By Harold Vance

The Lafitte field, the largest oil reserve in South Louisiana, is in Jefferson Parish, some 25 miles due south of the City of New Orleans. The discovery well, The Texas Company's No. I, Louisiana Land and Exploration Co., in the southeast corner of sec. 19, T. 17 S., R. 24 E., was completed on May 15, 1935. The initial production of this well was 960 bbl. of 34.9º A.P.I, gravity oil per day, through 1/4-in. choke, with a tubing pressure of 1600 lb. per sq. in. Producing depth was 9558 to 9572 ft., the total depth being 9572 feet. The development of the field has been at the rate of three to eight new producing wells per year. Up to Jan. I, 1944, 60 producing wells and three dry holes had been drilled, while two of the original producing wells had been abandoned, Although the field is not unitized, The Texas Company was the sole operator in the field until the Lafitte Oil Co. completed its NO. I Jefferson Parish, near the center of the west line of the NW/4 sec. 20, T. I7 S., R. 24 E., on July 27, 1941. No additional wells have been drilled by the Lafitte Oil Company. Drilling and WeLl-completion Practices All drilling operations have been conducted with the steam-driven rotary equipment mounted on submersible barges. A canal is dug to the well location and the drilling unit is floated into position. The seacocks are then opened and the barge settles to the bottom. After the well is completed, seacocks are closed and water is pumped out of the barge. This procedure permits the barge, with drilling equipment still in place, to be floated and moved off the location. The conventional open-hole and the gun-perforation method of completing wells has been used in this field. Where possible, the initial completion is from the deepest 'sand and recompletions are made progressively up the hole, by plugging back with cement to the upper sand and gun-perforating opposite the new sand. The oil string usually is 7 5/8 in., 26 to 34-lb. casing. Three wells have been completed using 9 5/8-in. 44-lb casing set below 10.000 feet. Fig. I shows the completion and recom-pletion practices on one well in the field. This figure also shows the relative locations of the different producing sands as shown on the electric well log. Structure The structure is an elongated dome, cut by two north-south faults, which divides the field into three segments. The west segment is the highest structurally and contains most of the recoverable oil and gas. The center segment is less important and the east segment is of little value. Figs. 2, 4, 6, 8 and 10 are depth contour maps on top of the five main producing sands in the field. These maps show the relative size of the five reservoirs and the

Jan 1, 1945

By Walter McKee

WHEN mixed with common cast steel in quantities ranging from 11 to 13 ½ per cent. and properly treated, manganese increases the ductility of the metal and adds greatly to its toughness and resistance to abrasive action, which properties comprise the distinctive characteristics that make manganese steel so valuable for many purposes at the present time. Manganese steel has been manufactured for about 26 years. .It was first made in a small way in England and subsequently produced in the United States in 1892. At present the manganese-steel foundries of this country have an annual capacity of about 60,000 tons and most of the growth has occurred within the past 10 years. In the early days of the industry it was impracticable to make manganese castings weighing over a few thousand pounds, but at present crusher heads, rolling-mill pinions, and similar castings weighing up to 30,000 lb. each are produced, and it does not appear that the limit of weight has been reached by a considerable margin. Manganese steel is similar in analysis to ordinary first-class converter metal except that it is high in carbon and contains from 11 to 13 ½ per cent. of manganese. From one standpoint manganese steel is similar to malleable iron in that the casting as it comes out of the sand is hard and brittle and must be made ductile by a heat-treating process. The heat treatment is an essential part of the process of making manganese-steel castings and must be properly carried out to secure satisfactory results. The necessity for heat treatment limits the thickness of sections which may be made of manganese steel. Originally the annealing depth was comparatively small, but researches carried on during the past few years have resulted in an increase in the thickness of section up to 5 ½ in., which it is possible to treat successfully. Large castings are cored out to a minimum thickness of 5 ½ in., thus not only eliminating some of the internal stresses which are invariably set up in a very thick casting, but also reducing the weight and inertia of the piece, an

Jan 12, 1915

By Maurice L. Pinel, Thomas T. Read, Thomas A. Wright

THE erroneous, but until recently widely prevalent, belief that iron castings were first made in Europe in the fourteenth century has been adequately refuted in a number of earlier papers;1,11,12 but except for an unpublished metallographic study by the late William Campbell, and a phosphorus analysis by T. A. Wright of the metal of the Han dynasty cast-iron stove described by Laufer,2 nothing was known of either the chemical composition or the metallographic structure of the metal of any ancient iron casting, although data on castings of recent manufacture are abundantly available. The metal of the stove, which had been buried in a grave for at least 15 centuries, was so corroded that it seemed inadvisable to publish the results on it until more and better specimens from other ancient castings could be obtained. During a journey through China, extending from Peking in the north to Canton in the south and Cheng-tu, Ssu-chuan, in the west, in the late summer and autumn of 1936, one of us (T. T. Read) was fortunate enough to obtain, and bring home for study, nine castings, all more than 1000 years old, of which the date of manufacture is precisely known because of inscriptions cast in them, another that lacks a dated inscription, but of which the date, as explained below, can be otherwise established, and a specimen from the largest iron casting ever made," which is also dated. The period covered by this suite of specimens extends from 502 to 1093 A.D. In addition, a sample was obtained from a casting of date unknown, but which was certainly cast before 1000 A.D. and possibly as early as the third century A.D. A detailed description of these specimens is as follows: 1. 502 A.D. A pair (right and left) of recumbent lions (Fig. 1). Base 7 ¼ by 14 3/8 in., height over-all 5 ½ in., weight 26 lb. each. The translation of the inscription on the base is: "Made on the twenty-fourth day of the seventh month of the third year of Ching Ming of Great Wei" (Sept. 11, 502 A.D.).

Jan 1, 1938

By Theodore Swann

DURING recent years, there has been a material increase in the use of ferrophosphorus in the steel industry. It has been observed, when rolling sheets, that those made of Southern iron did not have to be rolled at as high a temperature as the others and, consequently, did not stick together. The reason was found to be the phosphorus content of Southern iron. It was therefore thought that an addition of phosphorus to sheet steel of other than Southern origin would give the same result as the use of Southern iron. At first, this addition was made by intro¬ducing phosphate rock in the blast furnace and reducing it together with the iron ore; but, because of the necessity for only small quantities of this grade of iron, the process was not satisfactory. The manufacture of ferrophosphorus was then introduced, so that additions might be made to the open-hearth furnace or ladle. Ferrophosphorus was first manufactured in the blast furnace. This method, however, can only economically produce a grade of product up to about 20 per cent. To produce a higher grade, it would be necessary to charge a larger proportion of phosphate-bearing material; and as the rate of absorption by the iron is low, there would be an increased loss of phosphorus oxides. This feature makes the production of a higher grade ferrophosphorus in the blast furnace uneconomical. The use of high-grade ferrophosphorus in the steel requires a smaller addition and involves, besides the economies in handling, an additional economy in transportation. The alloy with a higher percentage than 20 per cent. can be made only in the electric furnace. In the ordinary operation of the electric furnace in the production of ferrophosphorus, an alloy may be produced containing 26 per cent. phosphorus; this is the limit, for it does not seem possible to produce a higher phosphorus alloy even if large excesses of phosphatic materials are used. The reasons for the difficulty in raising this percentage of phosphorus are not known. The compounds Fe3P, containing 15.6 per cent., and Fe2P, containing 21.7 per cent. phosphorus, have been studied and it appears as if the alloy produced, containing percentages of

Jan 10, 1924

By David Keys

THE object of this investigation was to determine with a vertical magnetic variometer the extent of the titaniferous ore deposit that occurs not far from Ivry in Terrebonne County, Quebec, about 70 miles north of Montreal. The Ivry mine, on lots 37 and 38 of range V, Beres-ford township, Quebec, is one of the largest and most accessible to transportation of the deposits of ilmenite in Quebec. The ore consists of an aggregate of ilmenite anhedra serving as host for numerous fine plaques of hematite. No magnetite is known from any occurrence near this lot, and in this way the deposit differs from many others that contain a large percentage of magnetite with the ilmenite. The deposit at Ivry thus has much lower magnetic susceptibility than those containing abun-dant magnetite, and a sensitive magnetometer was necessary for the work, although a body of magnetite with ilmenite about a mile from the Ivry mine was successfully prospected with a dip needle. The principal orebody is exposed in a quarry known as the Ivry mine, from which about 16,000 tons of ore have been shipped. Small exposures of ilmenite isolated by drift serve to show the presence at the surface of some of the bodies indicated by the magnetometer,- but most of the hill is covered with glacial till and second growth hardwood. At the lower levels the till gives place to fluvioglacial sands and gravels from which the forest has been cleared. The increasing thickness of the sand and gravel as the hill descends makes the tracing outward of the deposits from the rocky knob of anorthosite a difficult matter. Within the orebodies too, some masses of anorthosite persist, which may account for some local irregularities. Fig. 1 is a photomicrograph, taken by reflected light, of a typical specimen of the ore. The dark patches are hematite and the light parts are ilmenite. No trace of magnetite was found. Fig. 2 is a photo-micrograph of a thin section of the country rock showing the texture of the anorthosite. The mean of four analyses quoted by Robinson1 is: titanium, 19.26 per cent; iron 45:41 per cent.

Jan 1, 1936

By William Paxton Hewitt

Mineral deposits of western Utah and eastern and central Nevada have produced in excess of $8,500,000,000 since 1871. Through 1965, Bingham Canyon had produced over $4,600,000,000 and seven other camps over $100,000,000 each, principally from base metals. In addition, they yield iron and uranium ores; contain the world's largest beryllium reserves; and have produced the United States' most important gold discovery in 25 years. The area is famous for its silver production and its bonanza-type precious metal deposits, but such production has become unimportant. The area's greatest producers of metallic wealth are base-metal deposits in limestones and porphyry-type copper ores. In contrast to silver's decline, gold production has been rising-the result of by-product operations at Bingham Canyon. The area also contains gold deposits in which the gold is so finely disseminated it is not recoverable by panning. The area's gold ores frequently are associated with realgar, cinnabar, and carbon. The ore deposits generally are attributed to Tertiary intrusives,* but, at Mountain City, they may be related to Paleozoic volcanism. Mountain City has yielded rich chalcocite from quartz-pyrite-chalcopyrite bodies in siliceous sediments. Regional stratigraphy and structure are difficult to interpret, 69 per cent of the area being obscured by alluvium or volcanics. In general, central Nevada consists of chert, shale, silty sandstones, lavas, and pyroclastics; eastern Nevada and western Utah of many alternations of limestone, shale, and sandstone. Central Nevada has been structurally active since late Devonian. Although granitic stocks may have intruded eastern Nevada and western Utah prior to the Cretaceous, these areas remained quite stable until affected by the Laramide Revolution. Precambrian exposures, occupying 3 per cent of the area, have not been important hosts. However, the question is raised as to whether Precambrian carbonates, properly situated with respect to invading mineralizers, might yet prove to be important. This paper describes 16 precious metal camps, 6 limestone replacement districts, 2 silver-base metal vein deposits, and 9 miscellaneous types and discusses briefly the 11 * Some ores, as at Ely, are associated with intrusives of. Cretaceous age. major camps that are described in detail in this Volume.

Jan 1, 1968

By AIME AIME

EVEN though most of the program of the joint meeting at Easton, Pa., on Oct. 30 to Nov. 1. was devoted to the interests of combustion engineers rather than to coal-mining engineers, nevertheless the A.I.M.E. Coal Division was well represented, with 83, or close to one third of those in attendance giving this as their affiliation. The fuels division of the American Society of Mechanical Engineers had 108 representatives, and an equal number reported no society affiliation. Added to the men's total registration was that of some twenty ladies so the total attendance was in the neighborhood of 325, exceeding that of the last two joint meetings, at Birmingham and Columbus, and equaling the 1938 crowd at Chicago.

Jan 1, 1941

By Joseph Daniels

IN connection with a study of the feasibility of establishing a blast-furnace industry in the Puget Sound region of Washington, possible sources of ore supplies along the Pacific rim were investigated. Many of the South American countries are known to contain important resources of iron, particularly Brazil and Chile. This latter country, because of its position on the west coast and the easy accessibility of its de- posits, appeared to be a logical place to consider as a potential supply for the Pacific Northwest. Accordingly, a brief field study was made of the deposits in September, 1924. Attention was confined to a limited number of properties on the west coast in the provinces of Antofagasta, Atacama, and Coquimbo. Passing consideration was given to the question of coal resources, and a short visit was made to a blast-funace plant at Corral in southern Chile which had been operated for a limited period as a producer of pig iron. In the following paper, a brief outline is given of the general observations made and of the salient facts rioted in the time available for the general study.

Jan 1, 1926

By Arthur S. Dwight

From the latest and best literature on lead-smelting, little can be learned concerning the present state of the art of mechanical feeding in the United States. H. O. Hofman, in his Metallurgy of Lead (5th ed., 1899), briefly describes the main features of the system in use at Pueblo, Colo., and later (p. 235) says " the only successful mechanical feeding, as far as the writer is aware, is that found at the works of the Pueblo Smelting and Refining Co." H. F. Collins, in his Metallurgy of Lead and Silver (London, 1899), covers American practice pretty thoroughly; but as to mechanical charging, he says: "The German plan of taking off the gases by means of a small iron pipe suspended in the center, and the plan of charging by means of cup and cone, as in iron blast-furnaces, have both been tried, but have not found favor, chiefly on account of the difficulty of obtaining free access to the furnace-shaft for barring, etc., with such devices."' . H. W. Hixon, in his Notes on Lead and Copper Smelting (3d ed., New York, 1900), gives a description and drawing of the Hixon feeding device, as originally installed at East Helena. Evidence that this system of feeding has passed its experimental stage, and deserves more serious consideration than it has heretofore received, is furnished by two large plants—the Pueblo and the East Helena—of the American Smelting and Refining Co., where mechanical feeding has been in continuous and successful operation for a considerable period; one new plant now erecting at Salt Lake City, Utah, and one old one belonging to the same company, the El Paso works, now being rebuilt after a disastrous fire, in both of which mechanical feeding is to be a prominent feature ; one new plant of an independent concern at Torreon, Mexico, which will adopt mechanical feeding; and a number of other smaller plants, among

Jan 1, 1902

By R. E. Hudrlik, G. W. Preckshot

The diffusion coefficients of silver from solid silver in molten lead were measured to within ± 0.8 pet in a columnar type diffusion cell ower, the temperature range of 326° to 530°C. Fick's law describes the process up to 530°C where the laminar mechanism appareltly breaks down. These is negligible resistance at the interface as shown by mathematical analyses. The diffusion coefficients are found concentration independent. IT would seem that diffusion in liquid metals would be free of such effects as molecular structure, dissociation. polarization. and compound formation. This view was taken by Gorman and preckshot in their study of diffusion of copper from solid copper into molten lead. They reported diffusion coefficients which were independent of the concentration over the range of 478° to 750°C. They found that the Stokes-Einstein equation with constant radius of the diffusing specie represented the diffusion data better than Eyring's rate theory equation and Sheibel's correlation. The radius of diffusion was found to be that of the doubly charged copper. There appeared to be no resistance across the solid-liquid boundary. In the present work the diffusion coefficients for silver in liquid lead were measured over a range of temperatures of 350° to 505°C. The solubility of silver in lead over the range of 303° to 630°C was also obtained. These results are compared with calculated or correlated values or with data in the literature. EXPERIMENTAL Procedure—The experimental equipment techniques and procedures were those reported in detail by Gorman and preckshot9 and will not be repeated here. Measured values of WT, Co, A. L were obtained for various diffusion times and the diffusion coefficient was computed for the case of no resistance at the interface9, 11 by: WT/CoAL = 1- 8/p2 n=1 1/(2n - 1)2 exp[-(2n - 1)2p2 Dt/4L2] [1] or where there was resistance at the interface by: WT = 1- ?n=1 2h2/ap2L [sxp [-Dan2t]/[(h2 + an2) L + h] The roots an are those of the transcendental equation3 tan (an L) = Iz/cun. The diffusion coefficient is that defined by Hartley and Crank.7 The total silver in the lead cylinder and equilibrium slug was determined by a cupellation technique' with proper correction for losses. Analysis of known samples showed that this method is surprisingly accurate. The amount of silver in the lead adhering to the silver cylinder was obtained in the same fashion as shown by Gorman and preckshot.9 The small errors involved in this determination are not critical since the silver in this adhering lead layer is only 3 to 15 pet of the total diffused. Materials—Electrolytic silver containing 99.9+ pet Ag obtained from General Refineries of Minneapolis, Minn. was used for all but runs 7 and 8. For the balance of the runs this silver was reduced with hydrogen at 1100°C and its oxygen content was found to be about 0.017 pet. For the runs. 7 and 8, phosphorous-reduced silver of the same purity was obtained from Handy and Harman Co. of Chicago, Ill. The densities of the phosphorus-reduced silver and the hydrogen-reduced electrolytic silver were 10.484 and 10.487 g per cm3, respectively. These values agree with those reported for pure silver. Silver which was reduced at 900 C had an average density of 9.998 g per cm3, indicating porosity. This silver was used for a number of runs which were not tabulated in Table I. These are indicated by crosses on Fig. 2. The 99.999 pet Pb was obtained from the National Lead Co. Research Laboratory of Brooklyn, New York. DISCUSSION OF RESULTS The diffusion and solubility results are reported in Table I for eleven runs using either phosphorus-reduced electrolytic silver or hydrogen-reduced silver at 1100° C. The solubility data shown in Fig. 1 show the excellent agreement with that reported by Heycock and Neville.8 The data of Friedrichs5 apparently are in error. The experimental solubility data of this work are reported to 0.3 pet. The experimental diffusion coefficients computed from Eq. [1] are reported within 1.2 pet of the mean and are plotted in Fig. 2. These are expressed within +0.8 pet of the experimental values over the entire temperature range by: D= 8.26 x 10 -5 e-1925/RT . [3] There appears to be little difference due to the

Jan 1, 1961

By Arthur C. Spencer

(Glen Summit Meeting, June, 1911.) THREE great deposits of iron-ore, in Camaguey and Oriente Provinces, Cuba, are well known to me through careful field-examinations executed in the years 1901 and 1907. In 1901 I visited the Cubitas iron-ore district, which lies about 12 miles distant from the city of Camaguey in a northerly direction, and the Mayari district, which includes the Sierra Nipe, lying opposite Nipe bay on the north side of Oriente Province. In 1907 I again visited the Cubitas district, and also made a sojourn of several days in the Moa district, where the extensive deposits of iron-ore were observed and studied. The observations of 1901 were made under the auspices of the then Military Governor of Cuba; Gen. Leonard Wood, and my conclusions concerning the value of these deposits were incorporated in a report.1 The examination of certain denouncements of iron-ore in the Moa district in 1907 was made in behalf of iron-masters operating in the United States, to whom I reported the existence of large amounts of easily-workable limonitic iron-ore, properly designated " brown iron-ore " in the terminology now current among iron-ore producers in the United States. In 1908 I published a paper entitled Three Deposits of Iron Ore in Cuba, outlining the occurrence and origin of the surficial ores existing in the Cubitas, Mayari, and Moa districts.2 . 1 A Geological Reconnoissance of Cuba, by C. Willard Hayes, T. Wayland Vaughan and Arthur C. Spencer, printed as a part of the report of the Military Governor of Cuba for the year 1901, vol. i. 2 Bulletin No. 390, U. S. Geological Survey, pp. 318 to 329 (1908).

Mar 1, 1911

THE annual meeting of the Lake Superior Mining Institute was held on Sept. 7 and 8, Crystal Falls and Iron Mountain, Mich., being the principal centers of activity. Members of both institutes began assembling early, and by the evening of Sept. 6, some 60 had already arrived at Crystal Falls. The greater number arrived the following morning, however, and after the usual formalities of registration were attended to, the party were loaded into automobiles and set out on a tour of inspection of the mines near Iron River; some properties were passed through, and some were briefly visited to permit the inspection of any unusually interesting piece of equipment or detail of practice. The last stop of the morning was at the Caspian, Iron River, where the entire party was entertained at luncheon at the Caspian Club House. Both the food and the company were excellent, and as the weather was superlatively good (though the natives of the district modestly declared it was only ordinary autumn weather) the lunch was served on the lawn at the rear of the club, where the green turf, abundant flowers, and music by the band, added to the charm of good fellowship. The degree to which mining men have become addicted to golf was indicated by the large number of plus fours in evidence, whose wearers appeared just before lunch and disappeared immediately afterward.

Jan 1, 1928

By J. A. Fellows, Earnshaw Cook, H. S. Avery

THE increased use of heat-resistant alloys (26 per cent Cr, 12 per cent Ni, 16 per cent Cr, 35 per cent Ni, 12 per cent Cr, 60 per cent Ni, etc ) in recent years has been accompanied by continued demands by the consumer for improvement in properties The manufacturers of these materials, of necessity, have resorted to more critical studies of the basic causes of variations in fundamental properties To keep pace with the need for augmented information, previous techniques of investigation have been refined and new test methods and instruments created It is the purpose of this paper to describe the apparatus, experimental technique and precision of measurement that were employed in the exploration of properties of heat-resistant alloy presented in a companion paper† The detailed precautions in experimental procedure essential for attainment of accurate and comparable data at elevated temperatures cannot be too highly emphasized THE CREEP TEST Since the fundamental concepts of creep testing have been recognized for the past 20 years, present interest is restricted to refinements in equipment and experimental procedure The creep-test laboratory constructed for the American Brake Shoe and Foundry Co is designed to permit 1000-hr tests in the temperature range of 1200° to 2200°F with a choice of applied stress extending from 50 to 50,000 lb per sq in in increments of 50 lb per sq in To simplify the calculation of weight combinations, the loading beams (Fig I) are provided with counterweights to eliminate the tare The precision of the knife-edges (10 1 ratio) is such that a 10-gram weight placed on the upper specimen grip will be exactly balanced by a 1-gram weight attached to the loading shackle Check of the loading weights proved the maximum error to be 0 06 per cent Axial alignment is provided by crossed knife-edges in the grip seats The furnaces are similar in design to those of Crane and Company, Battelle Memorial Institute, and the U S Steel Corporation An 80 per cent Pt, 20 per cent Rh No 19 B and S gauge wire is used as the heating element The details of construction are shown in the radiograph reproduced in Fig 2 The windings are held in place on an alundum tube with alundum cement, the distribution of turns is adjusted to give a maximum temperature gradient of ± 1°F over a 4-in gauge length (Fig 3) To avoid sharp temperature differentials at the ends of the test section, the length of the furnace is four times the gauge length Sixteen-inch coupons are used to reduce the temperature of the threaded

Jan 1, 1942

By R. P. Smith

IN 1937 the employees of the Hollinger Consolidated Gold Mines Ltd., at Timmins, Ont., Canada, approached organized medicine for a plan to provide themselves and their families with a complete medical service including hospitalization. This approach was made because of two conditions: (1) the necessity for some organization whereby contributions could be made in instalments to offset the sudden and large expense connected with illness for which the average employee is not prepared, and (2) the need for a more cohesive quality of service to replace a contract practice then in vogue, which did not take care of the employee's family or dependents. In different parts of the United States and Canada similar plans were in force, not only for employed groups but for numbers of people in circumscribed areas. In Europe different countries had adopted various forms of health insurance plans. It then was no surprise that these employees as a group should ask for some similar plan. With the cooperation of the management, a plan was instituted. The plan has one object only-the provision of medical services, including the accessory services such as hospitalization, X-rays, nursing, and necessary drugs and medicines. It is not concerned with cash benefits, sickness and accident payments, or any form of monetary return as the result of illness, but is simply an organization to provide medical services and pay for them from a central fund. It is a nonprofit organization and the only shareholders are the employees and their families who contribute and who in turn receive services. The Hollinger plan is limited to the employees of the Hollinger mine, who live in Timmins and the immediate vicinity. At first, the membership was voluntary. In the third year, it was made a condition of employment, with the proviso that at the end of any Association financial year an employee may withdraw if he wishes to do so. After withdrawal, he cannot again become a member until the end of the next Association year, and then only by the payment of the back dues. This step was taken to ensure continuity, and to prevent employees from withdrawing when well and reentering when faced with impending illness or operations. The employee himself is subject to medical examination on application for employment, and if accepted is subject to further examination by a specialist in chest diseases under the Workmen's Compensation Board of Ontario. Thus it is possible to exclude those who have heart disease, tuberculosis, or other disabling conditions when first employed. Wives and families of employees are not subject to medical examination but other dependents of an employee-mother, father, or other relative-who are declared by the employee to be wholly dependent upon him must be examined. The employee

Jan 1, 1944

By Ballard H. Clemmons

THE future of the steelmaking industry of the Birmingham, Ala., district is closely related to and, in a large measure, dependent on the development of workable, economic processes of ore concentration. Operations thus far in the area have been possible only because of the fortuitous occurrence of iron ore, fluxing stone, and coking coal-all the primary iron-making materials- within a 25-mile radius of the blast furnaces. Commercial ore of the district consists mainly of a 10 to 20-ft hematite-calcite-silica bed locally known as the "Big Seam," a component of the Clinton formation of Silurian Age. At present mining rates, this ore will be available for a number of years. It is largely mined under 1000 to 2000 ft of cover and transported on 15 to 20" slopes that, in some instances, are as much as 10,000 ft long. Under these conditions, particularly with increasing distances from face to portal, mining costs are gradually becoming disproportionately high. Although not a major factor thus far, it should also be noted that the average annual ore output of the district is gradually be- coming more siliceous.

Jan 1, 1950

By J. D. A. Morrow

TO my mind the National Bituminous Coal Act so far has proved one of the unhappiest experiences that has ever befallen the bituminous coal operators of the United States. Viewed in the light of its ugly consequences everyone should recognize this measure for what it is -a weird thing as unreal as a page from "Alice in Wonderland." Indeed it might be another stanza to the tale of the Walrus and the Carpenter, with the coal operators in the role of the unfortunate oysters who were taken on that memorable ramble. It is time that coal producers open their eyes, jerk themselves out of any lingering hypnotic optimism about the price-fixing provisions of this law, demand the repeal of these corroding clauses, and then set about remedying as best they can the disastrous effects of this retromingent scheme to regulate the coal business.

Jan 1, 1939

Lead-zinc production in Canada accounted for 19% of the total value of metals and minerals produced in 1976, says Keith C. Hendrick, president of Noranda Sides Corp. Mine production of recoverable zinc w as 1. 158 million toils of 27.4% of free world production in 1976. Slab zinc pro¬duction was placed at 472,000 tons that year. Canadian mine production of recoverable lead was 247,000 tons or 10.6% of the free world production. Refined lead that year was at 177,000 tons.

Jan 11, 1977