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By L. A. Norman

ANOTHER chapter in the history of Mother Lode mining is being written by operations in the Old Eureka mine near Sutter Creek, Amador County, California. During a two-year period (1938-1939), 85,517 tons of ore averaging 0.62 oz. gold per ton were mined and milled, as compared to the production of approximately 210,000 tons of 0.315-oz. gold ore during the preceding seven years. This is a repetition of mining history in the Mother Lode, where a period of prosperity has followed a long period of lean production. The location of this new ore in the hitherto unproductive hanging-wall greenstones and its mining and geological developments are most interesting. HISTORY OF THE OLD EUREKA MINE The Old Eureka mine, also known as the Hayward, Eureka, Hetty Green and Amador Consolidated, is in the most productive 10-mile length of the 120-mile long Mother Lode of California. The mine was first opened in 1852 with operations more or less continuous for the next 30 years. Production during this period amounted to $12,000,000 from an ore shoot 500 ft. long, which bottomed 1700 ft. below the surface. The shaft was continued as a prospect to 2065 ft. on the incline, where work was stopped in 1881. The mine was sold in 1916 by Hetty Green and the shaft deepened to the 3500-ft. level (3212 ft. vertically) by the new owners. Drifts were run on the 1700, 2100, 3000 and 3500-ft. levels, together with approximately 1500 ft. of crosscuts. No ore was found and work was abandoned in 1921. The present owners, the Central Eureka Mining Co., purchased the mine in 1924 after threatened litigation over rights to the rich ore shoot being mined from the lower levels of the Central Eureka mine on the south. Rehabilitation of the shaft commenced in 1926 and in 1930 mining on the old 2100-ft. level was started. While efforts of the previous owners had been directed for the most part toward the area south of the Old Eureka shaft and adjacent to the productive Central Eureka mine, the present owners started drifting northward on the old 2100-ft. level. On the 2000-ft., 2100 and 2300-ft. levels, drifts were run in part along the

Jan 1, 1939

By F. C. NINNIS

AT THE Belmont mill, the pregnant solution is de¬livered to a 30 by 10-ft. tank, from which it is pumped to three Merrill clarifying presses of the sluice-bar type, whence it flows through the meter to the precipitation supply tank. ?The solution for precipitation is pumped by a 10 by 10-in. Aldrich triplex pump and delivered through a 6-in. line to the forty-eight triangular frame Merrill presses at the head of the mill. Zinc dust is fed in at the pump suction and the solution precipitated to 0.01 to 0.02 oz. silver. The solution flowing from the presses is tested at 1-hr. intervals with sodium sulfide. All solution is precipitated to the same value; 4J tons of solution are precipitated for each ton of ore treated and the presses are cleaned every 15 days. The product from the presses' is dumped into steel cars having steam-jacketed bottoms, in which they are dried until the moisture content is between 15 and 17 per cent. when 8. per cent. of soda and .3 per cent. of borax are added and the contents thoroughly mixed. In the case of special clean-ups, the precipitate is tested and the flux is added to meet the requirements.

Jan 1, 1921

By N. H. Emmons

An interesting development of copper blast-furnace construction has been brought about in adapting the blast-furnace to be a "burner" for sulphuric acid making. When the Tennessee Copper Co. first decided to construct an acid-plant, the standard type of brick-top furnace, supported by structural steel, was the only one in use at its plant. All the tests for temperature and strength of gas had been made on these furnaces, and had been satisfactory. When, however, the acid-plant was put on the flue, and the flue had to have a damper put in it to force the gas into that plant, troubles began. The furnaces were fairly tight, and for a few months the work was quite satisfactory. Fig. 1 shows the old type of furnace-top used at the start. It was soon found that this top would not stand the temperatures, particularly when dampered back, as was necessary to force the gas into the Glover towers. The structural steel, of which the furnace skeleton was constructed, warped and twisted so badly that it was not safe to use the furnaccs. This effect is shown by Fig. 2, which is a photograph of old No. 4 furnace, after the brick-work had been removed. It became apparent that a new type of top mas necessary and the engineering force was started on the design of a new furnace-top, with the result that a low top, with brick-lined flues at each end below the feed-floor, leading to the main concrete dust-chamber, was constructed. This furnace, No. 7, is shown in Fig. 3. The charging-doors are made of cast-iron sections, three sections to a door, and three doors to a side. A door to the furnace was made of east copper, but the heat was great that the copper bent readily, due to the jarring of its

Jan 1, 1911

By G. L. Schroeder

Investigations were conducted at two underground locations, foreman's room and 5702 area, of the Kermac Nuclear Fuels Corp. uranium mining installation, Ambrosia Lake, New Mexico. The rock environment is stratified sandstone. Pressures were varied from minus 0.4 an Hg to plus 3.8 cm Hg with respect to barometric pressure, and were maintained for periods ranging from several hours to 21 days. One cm Hg overpressure (-1.5% of normal barometric pressure) produced a 20-fold decrease in Rn flux into the foreman's room as compared to the Rn flux observed during dilution ventilation. The 5702 area experienced a 5-fold decrease in Rn flux for a similar overpressure. During 21 days of continuous 1 cm Hg overpressure in the 5702 area this reduced Rn flux was maintained. The smaller reduction in flux for the 5702 area results in part from the proximity of the foreman's room to a non-pressured area and the presence of an impermeable shale lens overlying the ceiling of the 5702 area. A 0.4 cm Hg underpressure of the 5702 area increased the Rn flux into the area by 3-fold over the non-pressured value. A barometric pressure influence on Rn flux into the mine and on air Rn concentrations in non-pressurd areas of the mine was measured. A falling barometric pressure causes an increase in the flux of interstitial gas into the mine; a rising barometric pressure decreases this flux. These effects are not seen in overpressured mine areas. Radon concentrations in rock interstices show, during overpressure, decreases of all locations monitored except in the immediate vicinity of the shale lens above the 5702 area ceiling. These reductions are the result of air flowing from the mine into the rock interstices under the influence of the pressure gradient induced by the overpressure. The relative humidity of the 5702 area was reduced after 2 days of 1 cm Hg overpressure from a pre-overpressure value of 96% to 81%. The control of harmful or noisesome gases which emanate into underground mining areas from surrounding rocks is often a costly necessity. In uranium (U) mines this problem is presented by the high interstitial concentrations of radon-222 (Rn), a radioactive noble gas of 3.82-day half-period, formed in the decay scheme of U238, and the relative ease with which this noble gas diffuses from its parent rock into the interstices of the rock and then to a working area. Long-term exposure to moderate concentrations of Rn (3000 µµc per 1) and its short-lived alpha-ray emitting daughter products, RaA (Po218) and RaC (po214), has been found to result in an increased incidence of bronchial carcinomaa2 The acceptable limit of Rn daughter products in a mine atmosphere is presently set at a concentration of short-lived radon daughters which would be in equilibrium with 100 ppc of Rn per 1 of air. Ventilation of mines is conventionally accomplished by continuously diluting the mine air with fresh air brought in by fan or natural convection from above ground surface. The diluted air is allowed to vent freely to the atmosphere. This process does nothing to retard the rate at which gases (including Rn) diffuse into the mine from surrounding rock. It merely reduces the concentrations of these gases within the mine. It is suggested that in a sufficiently permeable rock environment a slight pressurization of the mine air may induce air flow from the mine into the interstices of rock surrounding the mine. The convective flow of comparatively fresh air will reduce the concentration and the concentration gradient of undesirable gases in the rock interstices adjacent to the mine. Radon will diffuse counter-current to this convective flow at a rate proportional to its concentration gradient. In time, a steady state of convection and counter diffusion will be established. The Rn flux into the mine will never be reduced to zero, and will only asymptotically approach zero as the overpressure (and hence the convective velocity of purging air) approaches infinity. During 1963 and 1964, an investigation into the effect which such applied pressures have upon the Rn characteristics of a mine atmosphere was conducted at the Kermac Nuclear Fuels Corp. uranium mines, Ambrosia Lake (near Grants), New Mexico.

Jan 1, 1967

By P. D. Rao, H. B. Charmbury, D. R. Mitchell

As a result of a changing market pattern for anthracite, there is now an increasing demand for steam size and a decreasing demand for domestic sizes. To help the producer meet this new demand, the authors present the technical aspects of the problem of crushing domestic sizes to steam fineness and size. The market pattern for anthracite coal has changed considerably in recent years. The demand for domestic sizes has been gradually decreasing and the demand for the steam sizes has been increasing. The companies however aim for a maximum production of domestic sizes, since these sizes command premium prices. To meet the market demands, particularly in certain periods of the year, further size reduction of the coarse clean coal is necessary. The present practice of multistage crushing in toothed rolls leads to complicated flow arrangements and is high in cost. Data presented herein indicate that crushers with high reduction ratios could be used with a resulting simplification of crushing flows and an appreciable reduction of capital and operating costs. The different types of crushing equipment investigated included the rotary-type breaker, the jaw crusher, the impactor-type crusher, and the Aerofall mill. CURRENT PRACTICE The standard sizes of anthracite are presented in Table I and market specifications require that any given size be maintained with only a limited amount of oversize and undersize material. The 1958 prices of the various sizes also are presented, so it may be seen that size reduction is only performed when dictated by market demands. At the present time the general practice of crushing anthracite consists of removing the top size and crushing it in a toothed double roll crusher to the next largest size. Consequently, to reduce the domestic egg, stove, and nut sizes to steam sizes of pea, buck, rice, and barley, the original material must be screened to produce the three top sizes and each size must be crushed in three separate rolls to the next largest size. Each crushed product must then be rescreened to remove the oversize for re crush ing. Thus a typical operation would consist of scalping the egg size from a mixture, crushing it to stove size, and rescreening the product. This same cycle would be repeated for the stove and nut sizes requiring three screens and three crushers as well as conveying equipment to handle the crushed products. This results in an expensive series of operations to make a product which sells for a lower price. If the three top sizes are crushed in one operation to the smaller sizes then the yield of steam sizes is low and the production of Nos. 4 and 5 sizes is large. These sizes sell for lower prices than the steam sizes. A typical operation is presented in Fig. 1. From the figure it may be seen that the original cleaned anthracite contains 67.4 pet domestic sizes, 26.4 pct steam sizes, and 6.2 pct fines. After multistage crushing of the domestic to steam sizes the composition of the product is 0.6 pct domestic sizes, 89.6 pct steam sizes, and 9.8 pct fines. From a technical standpoint these results are reasonable but the handling and crushing costs are

Jan 1, 1961

By AIME AIME

THE graduating class whom I am particularly addressing are going into the world at least a month earlier than normal, because of the war. You have been free to choose your work. You have chosen to be mining engineers. The principal importance of your engineering education to date has been in teaching you how to think and how through books to have ready access to the accumulated experience of previous generations, as well as the current experience of the day. You should by now have acquired something of the engineering point of view, the open skeptical mind. the power to observe, experiment, and draw conclusions, form theories and test these by further experiment, and weigh the inherent probability of conclusions drawn by others. I am asking you today to consider certain facts and the conclusions I am drawing from those facts.

Jan 1, 1942

Jan 1, 1969

By Robert R. Walden, LaMont West

KENTUCKY'S first acid-grade fluorspar flotation mill, shown in Fig. 1, was placed in operation Aug. 1, 1952, by the Pennsylvania Salt Manufacturing Co. at Mexico, Ky. During 1951 a critical shortage of acid-grade fluorspar developed and it became necessary for the company to produce part of its fluorspar requirements. In 1951 the company purchased the Crider and Lennen metallurgical fluorspar mill and an adjacent stockpile of tailing at Mexico, Ky. The tailing, assaying about 26 pct calcium fluoride, originated from log washer and jig mill concentrators in the area. As the mill did not have a fluorspar dryer or convenient rail facilities, the company leased the Burleson concentrator at Marion, Ky., where these facilities were available. At Marion, Ky., on the Illinois Central Railroad, dry acid-grade fluorspar is transported direct to the company's Calvert City, Ky., hydrofluoric acid plant.

Jan 5, 1954

By J. L. Humphrey

The origin of roof bolting is obscure, but is believed to have begun some 40 years ago in the mines of St. Joseph Lead Co. in southern Missouri. It was not until after World War II, and more particularly after 1949, as a result of the concentrated effort of the USBM, that roof bolting attracted widespread interest. It is estimated that at the end of 1954, 26 pct of all bituminous coal mining in the U. S. was being done under roof bolts. Those mines alone use nearly 2,000,000 roof bolts per month, according to USBM statistics. Uses in metal mines are increasing rapidly, as confidence and knowledge grow. The application has found equal success in other fields, such as tunneling work for dam and waterway construction and right of way maintenance on highways and railroads.

May 1, 1956

LIST OF THE MEETINGS OF THE INSTITUTE AND THEIR LOCALITIES FROM ITS ORGANIZATION Transactions Number Place Date Vol Page 1 Wilkes-Barre, Pa May, ?71 1 3 2 Bethlehem, Pa August, ?71 1 10 3 Troy, N Y November, ?71 1 13 4 Philadelphia, Pa February, ?72 1 17 5 New York, N Y May, ?72 1 20 6 Pittsburg, Pa October, ?72 1 25 7 Boston, Mass February, ?73 1 28 8 Philadelphia, Pa May, ?73 2 3 9 Easton, Pa October, ?73 2 7 10 New York, N Y February, ?74 211 11 St Louis, Mo May, ?74 3 3 12 Hazleton, Pa October, ?74 3 8 13 New Haven, Conn February, ?75 3 15 14 Dover, N J May, ?75 4 3 15 Cleveland, 0 October, ?75 4 9 16 Washington, D C February, ?76 4 18 17 Philadelphia, Pat June, ?76, 5 3 18 Philadelphia, Pa October, ?76 5 9 19 New York, N Y February, ?77 5 27 20 Wilkes-Barre, Pa May, ?77 6 3 21 Amenia, N Y October, ?77 6 10 22 Philadelphia, Pa. May, ?78 6 18 23 Chattanooga, Tenn May ?78 7 3 24 Lake George, N.Y. Oct. ?78 7 25 Baltimore, Md. Feb. ?79 7 26 Pittsburgh Pa, May ?79 8 27 Montreal, Canada Sept, ?79 8 28 New York, N.Y. Feb, ?80 9 29 Lake Superior, Mich Aug, ?80 9 30 Philadelphia, Pa. Feb, 81 9

Jan 1, 1923

LIST OF THE MEETINGS OF THE INSTITUTE AND THEIR LOCALITIES FROM ITS ORGANIZATION Transactions Number Place Date Vol Page 1 Wilkes-Barre, Pa May, ?71 1 3 2 Bethlehem, Pa August, ?71 1 10 3 Troy, N Y November, ?71 1 13 4 Philadelphia, Pa February, ?72 1 17 5 New York, N Y May, ?72 1 20 6 Pittsburg, Pa October, ?72 1 25 7 Boston, Mass February, ?73 1 28 8 Philadelphia, Pa May, ?73 2 3 9 Easton, Pa October, ?73 2 7 10 New York, N Y February, ?74 211 11 St Louis, Mo May, ?74 3 3 12 Hazleton, Pa October, ?74 3 8 13 New Haven, Conn February, ?75 3 15 14 Dover, N J May, ?75 4 3 15 Cleveland, 0 October, ?75 4 9 16 Washington, D C February, ?76 4 18 17 Philadelphia, Pat June, ?76, 5 3 18 Philadelphia, Pa October, ?76 5 9 19 New York, N Y February, ?77 5 27 20 Wilkes-Barre, Pa May, ?77 6 3 21 Amenia, N Y October, ?77 6 10 22 Philadelphia, Pa. May, ?78 6 18 23 Chattanooga, Tenn May ?78 7 3 24 Lake George, N.Y. Oct. ?78 7 25 Baltimore, Md. Feb. ?79 7 26 Pittsburgh Pa, May ?79 8 27 Montreal, Canada Sept, ?79 8 28 New York, N.Y. Feb, ?80 9 29 Lake Superior, Mich Aug, ?80

Jan 1, 1923

By C. E. Shoenfelt

Operations ill Colorado oil fields in 1934 were not quite so extensive as in 1933, but much better results were obtained and one new oil field was discovered. In all, 26 wells were drilled, of which 9 were oil wells, 1 was a gas well, and 16 were dry holes. New oil production totaled 10,220 bbl. and new gas production totaled 33,714,000 cu. ft. This compares with new oil production in 1933 of 1238 bbl. and new gas production of 14,307,000 cu. ft. Dry holes in 1933 totaled 29 as conlpared with 16 in 1934. Oil was discovered in the Hiawatha gas field, Moffat County, in 1934 in the Mountain Fuel Supply Company's No. 4B Wilson, C. NE. NW. of sec. 23, 12N., 100W. This well was completed in a sand in the Wasatch (Tertiary) at 2304 to 2337 ft., after plugging back from 3797 ft. It made 20 bbl. of oil initially. No. 4B Wilson is the first well in the Rocky Mountain region to discover oil in commercial amounts in rocks younger than Cretaceous, and while it is not expected that Hiawatha will develop into an oil field of important proportions, eventually it may produce a considerable amount of oil as the gas pressure declines. The Hiawatha gas field was discovered in 1926, on one of six structures in what is known as the Vermillion Creek gas area. It is a northeast-

Jan 1, 1935

LIST OF THE MEETINGS OF THE INSTITUTE AND THEIR LOCALITIES FROM ITS ORGANIZATION Transactions Number Place Date Vol Page 1 Wilkes-Barre, Pa May, ?71 1 3 2 Bethlehem, Pa August, ?71 1 10 3 Troy, N Y November, ?71 1 13 4 Philadelphia, Pa February, ?72 1 17 5 New York, N Y May, ?72 1 20 6 Pittsburg, Pa October, ?72 1 25 7 Boston, Mass February, ?73 1 28 8 Philadelphia, Pa May, ?73 2 3 9 Easton, Pa October, ?73 2 7 10 New York, N Y February, ?74 211 11 St Louis, Mo May, ?74 3 3 12 Hazleton, Pa October, ?74 3 8 13 New Haven, Conn February, ?75 3 15 14 Dover, N J May, ?75 4 3 15 Cleveland, 0 October, ?75 4 9 16 Washington, D C February, ?76 4 18 17 Philadelphia, Pat June, ?76, 5 3 18 Philadelphia, Pa October, ?76 5 9 19 New York, N Y February, ?77 5 27 20 Wilkes-Barre, Pa May, ?77 6 3 21 Amenia, N Y October, ?77 6 10 22 Philadelphia, Pa. May, ?78 6 18 23 Chattanooga, Tenn May ?78 7 3 24 Lake George, N.Y. Oct. ?78 7 25 Baltimore, Md. Feb. ?79 7 26 Pittsburgh Pa, May ?79 8 27 Montreal, Canada Sept, ?79 8 28 New York, N.Y. Feb, ?80 9 29 Lake Superior, Mich Aug, ?80 9 30 Philadelphia, Pa. Feb, 81 9 31 Staunton, Va May, 81 10

Jan 1, 1923

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 Charles E. Locke

SHARP CONTRAST exists in the reports so helpfully contributed by the individual members of the Milling Committee for this review. Those engaged in the milling of gold and silver ores report great activity, of which some details will be given later. Those engaged in milling ores of base metals report continued depression and little progress. Copper production in the United States is running at about fifteen per cent of capacity. Some Arizona copper mills are closed. Anaconda is milling about 45.000 tons of copper ore per month, and the Utah Copper Co. 35,000 monthly. However, in Canada the International and Falconhridge copper-nickel mills and the Noranda copper-gold mill have increased production. Also the Climax molybdenum mill in Colorado is milling 4000 tons per day. Water shortage from the drought has caused curtailment or complete shutdown of mills in some parts of the West.

Jan 1, 1935

On the following pages are abstracts of papers published by the Institute during the year 1935 as TECHNICAL PUBLICATIONS and CONTRIBUTIONS, papers in bound volumes appearing for the first time, and papers in MINING AND METALLURGY. For abstracts of papers that appeared in bound volumes in 1935 but that were published as TECHNICAL PUBLICATIONS in 1934, see the YEAR BOOS dated January, 1935.. Many of the TECHNICAL PUBLICATIONS have been reprinted in bound volumes. Information regarding this disposition, and number of pages in each paper, may be found in the list beginning on page 64. Volume numbers are given as listed at the beginning of the index, page 71. The abstracts are grouped as follows: [Page Metal Mining 17 Uses of Metals 23 Milling and Concentration 23 Iron and Steel Division 26 Nonferrous Metallurgy (Reduction of Ores)...: 34 Institute of Metals Division (Founding and Metallography of Nonferrous Alloys) 36 Page Coal Division 43 Petroleum Division 50 Industrial Minerals Division (Nonmetallics) 57 Mining Geology 60 Mineral Industry Education Division 62 Geophysical Prospecting 62]

Jan 1, 1936

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

TEe 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 alloys 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 iaboratory constructed for the American Brake Shoe and Foundry Co. is designed to permit I000-hr. tests in the temperature range of I200° to 2 200°F. with a choice of applied stress extending from jo 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:I ratio) is such that a 10-gram weight placed on the upper specimen grip will be exactly balanced by a I-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, zo 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 aludum cement; the distribution of turns is adjusted to give a maximum temperature gradient of , I°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 joints and thus to facilitate removal from the grips. Thermal losses are minimized by refractory insulators cut to shape and surrounded by diatomaceous ear,th. The taps

Jan 1, 1942

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

TEe 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 alloys 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 iaboratory constructed for the American Brake Shoe and Foundry Co. is designed to permit I000-hr. tests in the temperature range of I200° to 2 200°F. with a choice of applied stress extending from jo 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:I ratio) is such that a 10-gram weight placed on the upper specimen grip will be exactly balanced by a I-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, zo 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 aludum cement; the distribution of turns is adjusted to give a maximum temperature gradient of , I°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 joints and thus to facilitate removal from the grips. Thermal losses are minimized by refractory insulators cut to shape and surrounded by diatomaceous ear,th. The taps

Jan 1, 1942

By N. R. MacMillan

INTRODUCTION The Bullmoose Coal Project is part of a major development in northeastern British Columbia which comprises a new rail line, a new townsite, powerline, highway, the upgrading of the Canadian National Railway's main line, a new coal port at Prince Rupert and two new coal mines, the Bullmoose mine and the Quintette mine. The total investment by all parties is estimated to be in excess of $2.6 billion and made up approximately as follows : [Table No. 1 $ Millions - Quintette Coal Limited 950 Teck-Bullmoose Coal Inc. 275 Canadian National Railway Company 800 6 British Columbia Railway Company Port at Prince Rupert 280 Townsite, Roads 6- Power ] The new infrastructure is intended to serve not only the Bullmoose and Quintette coal projects but also eventually a number of other coal properties in northeastern British Columbia. The Bullmoose project is structured on a joint venture basis as follows : [Table No. 2 Teck Corporation 51% Lornex Mining Corporation Ltd. 39% Nissho Iwai Coal Development 1 0% (Canada) Ltd. -- 100% ] The mine has a capacity of 2.3 million tonnes of clean coal per year. In the initial years 1.7 million tonnes will be metallurgical coal and 0.6 million tonnes thermal coal. After the first three years of operations the annual production of metallurgical coal will increase to an average of approximately 2.1 million tonnes and the production of thermal coal will decrease to an average of approximately 0.2 million tonnes. At this level of 2.3 million tonnes annual production, the Bullmoose mine has sufficient reserves for at least 26 years of production. History Brameda Resources Ltd. commenced coal exploration in the Bullmoose-Sukunka area in 1969. Teck obtained an option on the Bullmoose coal licences in 1970 and started surface exploration and diamond drilling in 1971. Teck earned a 50% interest in the property, and thereafter expenses were jointly financed by Teck and Brameda. In 1981 Brameda merged with Teck making Teck the sole owner. The initial phase of the exploration program, which was completed in 1975, included 7,200 meters of diamond drilling in 35 holes. During 1976 and 1977, detailed exploration and test work were carried out on the South Fork and West Fork areas where multiple seams close to surfaces indicated the potential for large tonnages of strippable coal. In those two years, work included road construction, detailed mapping and trenching to outline the coal seam traces at the surface, 6,300 meters of diamond drilling in 80 holes, and 300 meters of underground bulk sampling from seven adits. Washability tests and analysis work were carried out on the drill cores and adit samples, and pilot plant washability studies were undertaken. In 1978 and 1979 Teck engineers prepared open pit mining plans and production schedules and Kaiser Engineering was retained to prepare a layout of the plant preparation facility. A feasibility study prepared by Teck's engineering group in January 1982 was the base document used by the Lenders in assessing the technical and economic viability of the project. Property Location The property lies some 650 kilometers northeast of Vancouver, and 87 kilometers south by road from the village of Chetwynd. The Sukunka property (British Petroleum) adjoins to the north, the Mount Spieker property (Ranger Oil Option) adjoins to the east, and the Quintette property is located to the southeast.

Jan 1, 1985

On the Art of Metallography (Howe Memorial Lecture), by F. F. Lucas; Beneficiation of Iron Ore. Abstract of paper by C. E. Williams followed by Round Table Discussion; A Statistical Analysis of Blast-furnace Data, by R. 8. McCaffery and R. G. Stephenson; Air Discharge of Circular Tuyeres, by R. S. McCaffery and D. E. Krause; Open-hearth Steel Process as a Problem in Chemical Kinetics. by E. R. Jette; Carbon-oxygen Equilibrium in Liquid Iron, by H. C. Vacher and E. H. Hamilton; A Thermodynamic Study of the Phasial Equilibria in the Bystem Iron-carbon (Abstract), by Yap, Chu-Phay; Influence of Dissolved Carbide on the Equilibria of the System Iron-carbon (Abstract), by Yap, Chu-Phay; Inclusions and Their Effect on Impact Strength of Steel, I and 11, by A. B. Kinzel and W. Crafts: Method for Electrolytic Extraction of MnO, MnS, FeS and Si02, Inclusions from Plain Carbon Steels, by G. R. Fitterer; Permanent Growth of Gray Cast Iron, by W. E. Remmers; Some Notes on Blue Brittleness, by L. R. van Wert; Austenite-pearlite Transformation and the Transition Constituents, by A. Sauveur; Age-hardening of Austenite, by F. R. Hensel; Transformational Characteristics of Iron-manganese Alloys, by H. Scott; Composition Limits of the Alpha-gamma Loop in the Iron-tungsten System, by W. P. Sykes; Magnetic Properties Versus AUotropic Transformations of Iron Alloys, by T. D. Yensen and N. A. Ziegler; Dilatometric Study of Chrome-nickel-iron Alloys, by V. N. Krivobok and M. Gensamer; Low-carbon Steel, by H. B. Pulsifer; Bright Annealing of Steels in Hydrogen, by F. C. KeUey; Development of Continuous Gas Carburieing, by R. J. Cowan. Transactions, Institute of Metals Division, 1931. 500 pages. Index. Papers and discussions presented before the Division at Chicago, Sept. 22-26, 1930 and New York, Feb. 16-19, 1931. X-ray MetallograpIhy: X-ray Determination of Alloy Equilibrium Diagrams (Annual Lecture), by A. F. Westgren; Suppressed Constitutional Changes in Alloys. by G. Sachs; Texture of Metals after Cold Deformation; by F. Wever. Theoretical Metallurgy: Studies upon the Widmanatitten Structure. I.—Introduction. The Aluminum-eilver System and the Copper-silicon System; by R. F. Mehl and C. S. Barrett; Studies upon the Widmanstatten Structure, 11.—The Beta Copper-einc Alloys and the Beta Copper-alumnum Alloys, by R. F. Mehl and 0. T. Mareke; Application of X-rays in the Manufacture of Telephone Apparatus, by M. Baeyerts; Thermal Conductivity of Copper Alloys. 11.—Copper-tin Alloys; 111.—Copper-phosphorus Alloys, by Cyril Stanley Smith; Thermodynamic Study of the Equilibria of the Systems Antimony-bismuth and Antimony-lead, by Yap, Chu-Phay. Ganeral: Cemented Tungsten Carbide; a Study of the Action of the Cementing Material, by L. L. Wyman and F. C. Kelley; Influence of Casting Practice on Physical Properties of Die Castings, by C. Pack; Fabrication of the Platinum Metals, by C. S. Sivil; Effect of Certain Alloying Elements on Structure and Hardness of Aluminum Bronze, by 9. F. Hermann and F. T. Sisco. The WorkinG oF Metals: Metal Working in Power Presses, by E. V. Crane; Forming Properties of Thin Sheets of Some Nonferrous Metals, by W. A. Straw, M. D. Helfrick and C. R. Fischrupp; Die Pressing of Braas and Copper Alloys, by J. R. Freeman. Jr.; Plasticity of Copper-sina Alloys at Elevated Temperatures. by A. Morris: Directional Properties in Cold-rolled and Annealed Copper, by A. Phillips and E. 9. Bunn; Effect of Combinations of Strain and Heat Treatment on Properties of Some Age-hardening Copper Alloys by W. C. Ellis and E. E. Schumacher; Constituents of Aluminum-iron-silicon Alloys, by W, L. Fink and K. R. Van Horn; Equilibrium Relations in Aluminum-antimony Alloys of High Purity, by E. H. Dix, Jr., F. KeUer and L. A. Willey; Equilibrium Relations in Aluminum-magnesium Silicide Alloys of High Purity, by E. H. Dix. Jr., F. Keller and R. W. Graham; Constitution of High-purity Aluminum-titanium Alloys, by W. L. Fink, K. R. Van Horn and P. M. Budge; Experiments on Retarding the Age-hardening of Duralumin, by E. H. Dix. Jr. and F. KeUer; Aluminum-silicon-magnesium Casting Alloys, by R. S. Archer and L. W. Kempf; Modulurr of Elasticity of Aluminum Alloys, by R. L. Templin and D. A. Paul; Quenching of Alclad Sheet in Oil, by H. C. Knerr.

Jan 1, 1931