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By Gary E. Parish

TABLE OF CONTENTS Contents I. Introduction II. Purpose of the Paper III. Historical Perspective A. Existing Sources B. New Sources (NSPS) C. Hazardous Pollutants (NESHAPS) D. Enforcement/Judicial Review 1. Title I Enforcement 2. Title III Enforcement 3. Information Gathering E. Summary IV. The Clean Air Act Amendments of 1977 (1977 Act) A. SIP-Related Provisions 1. Section 107(d) - Geographic Boundaries 2. Section 108 - Air Quality Criteria 3. Section 109 – NAAQS 4. Section 110 – SIPs 5. Section 122 and Sections 402 and 403 of P.L 95-95 – Unregulated Pollutants 6. Emission Offsets – Interpretive Ruling (I.R.) B. PSD Provisions - Part C. 1. Regulations Under the 1970 Act 2. The 1977 Act 3. Regulations Under the 1977 Act C. Visibility Protection - Part C, Subpart 2 D. Non-Attainment Provisions - Part D E. Monitoring and Modeling F. NSPS G. NESHAPS H. Enforcement/Judicial Review 1. Title I 2. Economic Enforcement 3. Title III Enforcement/Judicial Review (a) Section 304 (b) Section 307 4. Summary V. Special Problems and Opportunities for the Uranium Industry A. End Use B. Transportation C. Milling/Processing D. Extraction E. Exploration/Discovery F. General VI. Conclusions Appendix A Footnotes

Jan 1, 1979

By Fulton B. Flick

The micrography and macrography of aluminum and its alloys present certain difficulties. Many of the difficulties attendant on the micrography have been removed by methods developed during the past few years, notably those of E. H. Dix, Jr.1 The development of grain size in aluminum and its alloys may be equally troublesome, yet comparatively little detailed attention appears to have been given to it. Satisfactory reagents are available for the development of such structurcs in ferrous and most non-ferrous metals, but those applied to aluminum and its alloys, i. e., alcoholic or aqueous solutions of sodium hydroxide or hydrofluoric acid are not entirely satisfactory. Hanson and Arch-butt,2 in speaking of these two reagents, state that "These two reagents give fairly satisfactory results, but they sometimes produce badly tarnished surfaces from which the surface deposit is difficult to remove." It has been our experience that neither of these reagents is to be entirely relied on for developing structures suitable for study or photography. This means that when the etch fails to produce satisfactory results the specimen must be repolished, through the 000-paper at least, and then etched with another reagent. This procedure entails a considerable loss of time, and the final results may not be all that might be desired. However, the reagent to be described, although not a panacea for all etching troubles, has improved results so markedly that it is felt that it & worth offering as a grain-size etch generally applicable to aluminum and aluminum alloys. Czochralski3 in 1915 mentioned the application of a solution of 10 to 20 c. c. concentrated hydrofluoric acid in 100 c. c. absolute alcohol, etching in this reagent being followed by dipping in concentrated hydrochloric acid soliltion.

Jan 1, 1925

By D. L. Ritter, N. J. Grant, B. C. Giessen

Forty-six alloys covering the complete concentration range of the Nb-Rh system were examined by metallographic and X-ray methods; solubility limits of terminal ad intermediate phases and transformation and solidus temperatures were determined. There are nine intermediate phases; two eutectic, five peritectic, two eutectoid, and three peritectnid reactions were encountered. The experimental methods and the constitution diagram are described in Part I. Part 11 deals with the crys -tallography and relation of the intermediate phases. The Nb-Rh system was selected for study for three reasons: first, it was hoped that the anticipated similarity of the Nb-Rh phase diagram to the Ta-Rh1 and Ta-Ir2 diagrams treated earlier (see also Ref. 3) and to the Nb-1r4 diagram treated simultaneously would allow a crystallographic and comparative evaluation of the intermediate phases in these related systems; second, it was likely that the previous experimental methods could be carried over without significant change; and third, it was expected that the interesting mechanical properties of the a1 phase of the Ta-Rh and Ta-Ir systems would also be encountered in similar phases of the new systems, and that these phases could be investigated more closely. The phase diagram had not been treated fully in the literature; only brief surveys of some intermediate phases were found.5-7 It was attempted to cover the details of the phase boundaries, Part I, as well as to present the crystallography of the intermediate phases, Part 11. EXPERIMENTAL METHODS Specimen Preparation and Treatment. The following high-purity starting materials were used. 1) Niobium powder, 99.8 pct pure, mesh size -60 +200, from Wah Chang Corp., Albany, Ore. The analysis furnished by the supplier showed the following major impurities: Ta, <500 ppm; Zr, <500 ppm; 0, 300 ppm; Fe, 280 ppm; Ti, <I50 ppm; W, Si, <100 ppm; C, N, 30 ppm; all other impurities, <30 ppm. 2) Rhodium powder, ground sponge, 99.9+ pct pure, mesh size -80, from J. Bishop Co., Malvern,

Jan 1, 1964

By Hansheinz Portisch, Harold Margolin

A surface expansion was found to occur sometime after etching in Ti-A1 alloys containing 9.5 to 12.5 wt pct Al. The structure formed, grew, and disappeared with tzrrze. The surface expansion was followed by microscope observations and interferometric and lattice parameter measurements. Activation energy measurements for the growth of the "expansion structure" and chemical analysis indicated that the phenomenon occurred as a result of hydrogen pzckup during etching. It is proposed that hydrogen initially enters octahedral sites of Ti3Al coherent with a Ti and later shifts to the tetrahedral sites. It is postulated that expansion occurs when hydrogen enters the tetrahedral sites. The expansion structure disappeared, it is proposed, because of diffusion of hydrogen from the surface into the body of the alloy and because of loss of coherency of Ti3Al. In examining Ti-A1 alloys, Ence and arolinl observed markings on the surface of specimens. These markings did not appear after electropolishing only, but rather appeared only after etching. The markings appeared to grow as a function of time after etching and later seemed to disappear. Although the markings had some similarity to precipitates, showing, frequently, a Widmanstatten type of arrangement, the observation that other microstructural markings continue to be seen within the new structure suggested that it was actually not a precipitate. The source of this structure was unknown and an attempt was made in the present investigation to develop some understanding of its nature. It has been labeled expansion structure. 1) EXPERIMENTAL PROCEDURE A) Alloys. Alloys in the range 6.5 to 14.5 wt. pct A1 were studied. Bars, 4 in. sq, forged from Bureau of Mines (73 Bhn) titanium consumably arc-melted 4-lb ingots,&apos; as well as 50-g arc-melted buttons of desired aluminum contents were used. The 50-g buttons also used Bureau of Mines titanium (73 Bhn) and aluminum of 99.99 pct purity. Buttons containing up to 8.5 wt pct A1 were hot-rolled from a furnace at 900&apos; . Those with higher aluminum contents were hand-forged on a titanium anvil, and heated with an oxygen-hydrogen torch in the region of 1200" to 1300°c. Frequent reheating kept the samples at the desired temperature range. After a reduction of about 30 pct, the samples were water-quenched. To eliminate any contamination picked up either during hot rolling or forging, at least 1 mil of the surface of the sample was taken off. B) Heat Treatment. Prior to heat treatment all alloys were vacuum-annealed to remove hydrogen. Samples were annealed at 900&apos; until a vacuum of 10&apos;5 mm Hg was established. After this treatment, the samples were wrapped in molybdenum sheet and heat-treated in argon-filled quartz capsules, which were broken under water or iced brine at the conclusion of the heat treatment. All heat treatments under dynamic vacuum were performed in a rapid-quench furnace. This consisted of a molybdenum-lined quartz tube attached to a vacuum system and through a stopcock to a beaker of water. At the completion of the heat treatment the vacuum stopcock was closed, the furnace shut off, and dropped below the quartz tube. Then immediately the inlet stopcock was opened and water admitted until the tube was filled. The steam formed was allowed to escape through the inlet stopcock. This method was used in heat treatments up to llOO°C. C) Metallography. Specimens for metallographic examination were ground, then electropolished using a Disa Electropol machine with a perchloric acid electr01te. Specimens were etched with R-etch.3 A standard etching time of 3 min was used, with the specimen being agitated during immersion. D) Sample Preparation for X-ray Analysis. Samples 0.2 to 0.5 mm in diam were produced from heat-treated rods which were turned to 2 mm diam on a lathe and then rotation-etched. An etchant consisting of 1 pt HF, 7 pt HN03, and 12 pt HzO was satisfactory. With the rod rotating in a vertical position at 50 to 100 rpm, a needle with uniform dimensions could be obtained. Care had to be taken to insure that the rod was at the center of rotation, otherwise cavitation developed. If a small unevenness developed, it was possible to grind it off with a fine emery paper. E) X-ray Diffraction. All X-ray work was done on a North American Phillips X-ray diffraction apparatus and a Jarrell Ash microfocus X-ray unit. The Phillips unit was used with a copper target and nickel filter. The Jarrell Ash unit was fitted with a cobalt target and iron filter. For the Phillips unit 35 kva and 20 ma were used, whereas for the microfocus unit with the 100-p fixed-focus gun 40 kv and 1.5 ma were used. It was found that alignment of cameras on the Jarre11 Ash unit was very critical. The X-ray beam contains an intense area which is not the beam center. The cameras were aligned with the intense region by monitoring the beam coming out of the camera with a Geiger counter. Adjustments were made until a maximum intensity was obtained. A Phillips diffractometer with a Brown chart recorder furnished some of the lattice parameter data. The divergence slit up to 80 deg 28 was I deg; above 80 deg, a 4-deg opening was used, while the scatter slit was1 deg and the receiving slit had a 0.003-in. opening. The general scanning rate was 1 deg per min, while peaks of special interest were rescanned at -j deg per min. For elevated-temperature X-ray diffraction a Uni-cam High Temperature Camera with a film diameter

Jan 1, 1969

By John J. Gilman

BECAUSE of their layerlike structure, zinc crystals exhibit strong anisotropies for almost all physical and chemical properties. This should, and indeed does, greatly influence the plasticity of zinc for various crystal orientations. At low temperatures, the investigator of this plastic anisotropy is plagued by the great variety of deformation modes that operate. However, at high temperatures (250° to 419°C) only two deformation modes predominate: basal (0001) and prismatic (1010) glide. Furthermore, since strain hardening is virtually absent at high temperatures, the plasticity for these two modes of deformation can be very simply described by means of two equations of state. It is the purpose of this paper to describe the experimental behavior of basal and prismatic glide in zinc crystals, and to interpret this behavior in terms of other physical properties (in particular, the thermal expansion coefficients and the elastic constants) using the theory of dislocations. Fig. 1 defines the two planes of the zinc structure that will be discussed. Glide occurs very readily on the basal planes at all temperatures, and there is a very large literature on this subject. Much of the literature has been reviewed by Schmid and Boas;&apos; it will not be reviewed here. Kolesnikovl was the first to show that if basal glide is circumvented by stressing a zinc crystal parallel to the basal planes (giving zero shear-stress on the basal planes) then, at temperatures above about 320°C, glide on the first-order prism planes occurs. His results have recently been confirmed by Cahn, Bear, and Bell." These previous workers have established the existence and crystallographic elements of prismatic glide; the present paper is concerned with the stress, strain rate, and temperature relations of prismatic glide as contrasted with basal glide. Experimental Methods The crystals were square ones, 6x6 mm, that had been grown in precision Pyrex tubes by a method that is described in detail elsewhere.&apos; Most of the crystals were 99.999+ pct Zn (New Jersey Zinc Co. CP grade). Some were alloyed with 0.1 -+-0.005 atomic pct Cd, and chemical analysis showed that almost all of the added cadmium persisted through the crystal-growing process. For measurements of nonbasal glide, crystals were oriented with their basal planes parallel to both the rod axis and one of the flat faces of the square cross section. However, the orientation of the close-packed directions [1210] with respect to the rod-axis was variable. For basal glide measurements, the angle between the basal plane and the specimen axis was 35". The orientations were measured by the Gren-inger back-reflection X-ray method. The problem of finding a suitable method of gripping the crystals was the most serious experimental obstacle that arose. Because of the large plastic anisotropy of zinc, the usual gripping methods were unsatisfactory. Some methods that were tried were: high melting-point solder, making heads on the ends by locally melting a crystal, and electroplating nickel on the ends to form enlarged portions. For all these methods, the regions of the grips were weaker than the crystals themselves. Finally, two methods were decided upon: bend tests and direct machining of tensile specimens. In the bend tests, specimens were loaded as simple beams so that gripping was not a problem. The beams were 1 in. long and the axis of bending was parallel to the hexagonal axis of the crystals. For the crystals that were machined into tensile specimens, brass bars with slots in them were used to support the crystals, and thereby minimize the distortions due to machining. The crystals were glued into the brass bars with plastic cement which was later dissolved away with acetone. See Fig. 2, left. No clamps were used near the crystals and the machining was done using a milling machine with a fly-cutter. The tool bit was very sharply pointed to minimize burnishing. The feed was less than 1 mil per cut. The depth of cut was 2 mil for roughing cuts, and % mil for the finishing cuts. This machining method produced surface layers of tiny recrys-tallized grains only 2 to 3 mil deep, and the bodies of the crystals were not measurably disturbed. After the crystals had been machined and removed from the brass holders, they were chemically polished until about 5 mil had been removed from all their surfaces. The polishing reagent consisted of equal parts of concentrated HNO,, 30 pct H3O and ethyl alcohol; it is described in detail elsewhere." A typical crystal is shown in Fig. 2, right. The I-shaped faces are normal to the hexagonal axis of the crystal; otherwise the projections at the ends would simply shear off when the crystal was loaded. The cross section in the 2?-in. gage length is 0.215x0.115 in. It was found that the polished

Jan 1, 1957

By R. R. Templeton

THE year 1924 was particularly notable in the petroleum industry of California as it was a period in which extensive town-lot drilling, with attendant overproduction and allied problems, virtually ceased and the industry returned to a nearly normal condition. Nearly all major field operations were conducted by large operating and marketing companies; in contrast to 1922 and 1923 field operations, when small promotion companies set the pace and forced the large companies to follow. The outstanding features of petroleum development were: 1. The three major fields of 1923, namely Huntington Beach, Long Beach, and Santa Fe Springs, declined from a production of 13,042,939 bbl., in January, to 6,764,417 bbl., in December, a drop of nearly 52 per cent: During this period, Huntington Beach declined 35 per cent., Long Beach 42 per cent., and Santa Fe Springs 63 per cent. 2. Methods of pumping deep wells were improved in some particulars; this contributed toward sustaining the productions of these three famous fields above what was predicted. 3. Of the fields producing previous to 1924, only three increased in production to any appreciable degree, during the year, as the result of bringing in new wells. These fields are Dominguez, Torrance, and Wheeler Ridge. Dominguez, discovered in September, 1923, produced 56,851 bbl. in January and increased regularly to a production of 1,641,042 bbl. in December. Torrance increased from a production of 972,261 bbl. in January, to 1,783,670 bbl., in May, and then declined to 1,393,215 bbl. in December. Wheeler Ridge, discovered in January, 1923, produced 23,254 bbl., in January, 1924, increased to a high of 33,678 bbl., in September, and declined to 27,430 bbl. in December. 4. Nearly all the production that had been shut-in during 1923 was opened in 1924, except some wells chiefly in Coalinga, Fullerton, and Santa Maria districts. The opening up of this shut-in production, combined with the increased productions from Dominguez and Torrance, were the chief factors that held the rate of decline for the state to a gentle slope.

Jan 7, 1925

By Persifor Frazer

I DESIRE to say that, owing to the number of papers which have been more or less crowded at this session of the Institute, and the fact that, as one of the Local Committee, I have the distinguished honor to feel somewhat like one of the hosts, I should not tax the patience of members at this late hour, but would have my paper read by title were it in any way possible to do this. But the task I have set myself this evening is to present to the eyes of the members of the Institute certain objects which have occupied more or less of my time during the last eighteen months or two years. The objects I allude to are some of the igneous rocks of this country, which, until quite recently, have been less understood than any others. It will be well known to some of the members that some of the cooled lavas of a previous age of our planet, when not directly coarsely crystalline and granular, were considered and spoken of as " natural glasses," or perfectly uncrystalline, vitreous, or hyaline masses of matter. Among the first results of the use of the microscope was the dispersion of this fallacy. Sir David Brewster, Mr. H. C. Sorby, and William Nichol (the discoverer of the celebrated calcite prism, which bears his name), had, with greater or less success, examined sections of various rocks and minerals, both by transmitted and reflected light, and also in the form of powder. But, until the genius of Vogelsang undertook the subject, these investigations had no permanent value, nor did they constitute an independent line of mineralogical and geological research. Since the close of his labors, by Vogelsang&apos;s premature and much-lamented death, the subject has been made one of renewed interest by his brother-in-law, Ferdinand Zirkel, as well as by Rosenbusch, Tschermak, and many others abroad, and at home by the commencement of a systematic study of the traps of Connecticut by Messrs. E. D. Dana and G. W. Hawes, of New Haven, and by the splendid set of described sections of the traps of the West which have been furnished by Zirkel to illustrate Clarence King&apos;s report. I had the honor of presenting a large number of thin sections of our traps at the Washington meeting, for the inspection of the members, with the aid of a table microscope belonging to the Smithsonian Institution. Here I propose to project these sections upon the

By Nathaniel Arbiter, Norman L. Weiss

Factors now accelerating the trend to larger concentrators and larger equipment units are reviewed. After almost 40 years of stability with unit sizes less than 100 cu ft, 200 and 300-cu-ft flotation-cell units are now operating and a 500-cu-ft machine is being built. The design of these cells is considered, as is the design and operation of flotation circuits against the background of the need to achieve greater process efficiency while holding down operating and investment costs. Particular attention is paid to the scale-up problem. With the newer cells having five to ten times higher unit capacities, the advantages resulting from this in sampling, mill operation nnd control, testing and plant layout are indicated, as well as the broad direction for changes in the overall design of 50,000 to 100,000-tpd concentrators. A comparison is given of the available larger cells of U.S. manufacture with analysis of differences and similarities. After almost 60 years of application in this country, froth flotation is still by far the most important process for concentrating metallic ores as well as a number of nonmetallic ores including fluorspar, phosphate rock, and potash. Its use on iron ores and coal is increasing. In the metals groups, the largest plants and the greatest progress are found in copper and molybdenum mills, and the section of this paper that deals with applications will be found most pertinent to that field. During its long reign, the flotation process has passed through several phases of evolution and has achieved progress in economy, efficiency. and simplicity of operation. Much of today&apos;s success in the flotation of low-grade ores can be attributed to that progress. Even more important to us than our ability to cope with today&apos;s conditions are tomorrow&apos;s problems, which we can contemplate with some prescience and confidence. Our annual production of copper, lead, zinc, and molybdenum—to mention only the most important metals occurring in the U.S. as sulfides- must be held at a high level in the face of a declining grade of ore. It is probable that the tonnage of such ores mined and processed will double in this country before the turn of the century. Not only will many of the existing flotation mills be enlarged again and again, but larger mills will be built here and abroad to meet our needs. At this moment, in fact, there are at least three proposed new foreign mills or expansions that envision 100,000-tpd milling rate on copper ores. Table 1&apos; shows the trend in copper ore grades in U.S. in recent years. Table 2&apos; shows the projected annual growth rate of consumption 1966-1985. A study by one of the authors 25 years ago showed that of 32 copper mills in North America with more than 100-tpd capacity, only eight had capacities exceeding 10,000 tpd. The average for these eight was 25,000 tpd. These included the three giants of that day, Magna, Arthur, and Morenci; the other five averaged a little over 10,000 tpd. Today instead of the eight mills with capacities exceeding 10,000-tpd capacity we have 25, and the mill with less than 1000-tpd capacity is fast becoming extinct. Much less range is found in lead and zinc mills, which are still generally small except for the few with over 1000-tpd capacity in Missouri, Utah, and Idaho, and a few zinc ore mills in the same size category. Molybdenum and potash operations are the fastest growers in North America today, but when one considers the projected increase in consumption of copper together with the projected decrease in grade of ore (3% annually), he can foresee that copper ore milling will soon lead the list. Technological improvements to meet the challenge of lower-grade ores have taken the wholly predictable path toward bigger equipment. In mining, shovels, draglines, scrapers, and trucks have led the way; in ore processing, we have seen a rapid increase in size of grinding mills, flotation cells, and pumps. Twenty-five years ago, for example, the 10-ft-diam ball mills treating 2000 tpd at Morenci were considered the giants, but today some grinding mills in similar service have five times that capacity. The specific matters to be dealt with in this paper are 1) the underlying principles that affect flotation-machine design, and the conditions required to produce

Jan 1, 1971

By George W. Neumann

The mines and concentrator of Brunswick Mining and Smelting Corporation are located in the northern part of the province of New Brunswick, approximately 20 miles distant from the City of Bathurst. Discovery of the No. 6 orebody by diamond drilling in 1952 was followed by the finding in March 1953, of the larger and higher- grade No. 12 orebody, approximately six miles to the north of the No. 6 deposit. Original development was financed by St. Joseph Lead Co., and included a small open-pit operation with a 10C ton per day pilot mill at No. 6 orebody, shaft sinking and underground development at No. 1; orebody, and an extensive program of laboratory and pilot plant metallurgical research on No. 12 ore. These operations were suspended in May 1958, and remained in standby condition until June 1961, when the equity of St. Joseph Lead Co. was purchased by a group headed by M. J. Boylen, K. C. Irving, Maritime Mining Corporation, and the Patino Corporation. Construction of a mine plant and concentrator at the No. 12 mine commenced in October 1962 and the concentrator was placed in operation in March, 1961b. Preparation of the open pit mine for production, construction of the No. 6 Concentrator to produce bulk Pb-Zn-Cu-Ag concentrate from No. 6 ore, and construction of an Imperial Smelting Process smelter at Belledune were started in 1964 and placed in operation in September 1966.

Jan 1, 1970

By J. D. Wright

INTRODUCTION The Endako deposit was first explored in 1926, but development waited until the early nineteen sixties. It first came under the control of Placer Development in 1963, and early in 1964 a decision to bring it into production was reached. The deposit is located near the geographic center of British Columbia, and is served by an east-west communication system including a paved highway, mainline railway and good telephone, teletype, and computer facilities. The plant area is shown in Figure 1. The operation is known as the Endako Mines Division of Canex Placer Limited of Vancouver. First production was achieved in June, 1965, at a nominal rate of 10,000 tons per day, but it soon was closer to 15,000 tons per day. In 1967, two new grinding and flotation, sections brought capacity to the present rate of approximately 27,000 tons per day. With mill heads of around 0.15 percent MoS2, production is about 14,000,000 pounds of molybdenum per year. A flowsheet of the operation is given in Figure 2. A legend for this flowsheet is given in Table 1. Published ore reserves are estimated at 214,500,000 tons at an average grade of 0.143 percent MoS2. PRIMARY CRUSHING The 85 or 100-ton haulage trucks dump over a grizzly into a 42 inch x 65 inch C.A.C. (Canadian Allis Chalmers) gyratory crusher. The

Jan 1, 1976

By Benjamin LeRoy Miller, Joseph T. Singewald

For a number of years Russia, India and Brazil have outranked all other countries as producers of manganese ores. During the 5 years immediately preceding the European war, the average annual production of Russia was 844,000, of India 694,000 and of Brazil 200,000 long tons. Since the outbreak of the war there has been a considerable falling off in the Russian and Indian production, particularly in the former, whereas the production of Brazilian ores has been greatly increased, amounting in 1914 to over 250,000 tons and in 1915 to nearly 350,000, with conditions favorable for a still larger production in 1916. Manganese is one of the few industrially important metals that are not produced in the United States in quantity commensurate with our needs, so that we have been compelled to import annually about 300,000 tons, having a value of over $2,000,000, and these ores have been obtained from the three countries mentioned above. Their rank as contributors to our imports of manganese ores was India, Russia, Brazil; and in 1913, Brazil contributed only one-fifth. During the past 2 years Brazil has furnished rapidly increasing quantities to this country, and, with the falling off of imports from India and Russia, has become our principal foreign source. In 1914, Brazil furnished two-fifths of the imports and more than India or Russia, and in 1915 over nine-tenths. The manganese ores of Brazil are consequently of more than usual interest to us at this time. The Manganese-Ore Distbicts of Brazil , The manganese mining industry of Brazil dates from the year 1894, and since that year the total production has been over 3,000,000 tons. With the exception of a small quantity produced in the State of Bahia from deposits west of the City of Bahia, this output has come from the

Jan 1, 1917

By William Glenn

The taking of proper samples of crude ores seems to he less thoroughly understood, or less carefully practiced, than its impor tance requires. We all know how often we encounter the reports of very accurate assays and analyses, the weight of which as evidence wholly depends on the method of obtaining the sample, and is very probably nil, because there has been no proper sampling. Pissages might be cited from technical books, and from current technical literature (all the work of writers whom we delight to honor) to show that even among high scientific authorities there is too little acquaintance with the practical art of the sampler. There is no metallurgical or chemical establishment which does not frequently receive samples truly representing nothing. They consist usually of bits of ore, or what not, selected because they are worse or better than the average of what they are meant to represent. And they are worthless, no matter who made the selection. Where conscious choice is permitted to enter into the operation, a fair sample will not result, unless by a miracle. The work of sampling is often looked upon as within the realm of boys and of pensioners only. At least, though the manual labor be left to subordinates, the principles on which it is conducted and the safeguards with which it is surrounded are not unworthy of the study of experts; and experts should he ready to teach these principles and enforce them in practice. For exact sampling is the indispensable first step towards learning the value of any boxful, carload or shipload of ore. I propose to give a simple account of the method of sampling by hand, such as I have always pursued. There is nothing new about it. So far as I know, it is the immemorial old method, as old at least as Cornish copper-mining. Perhaps my fellow-members in the Institute may suggest improvements in it. If not, it will constitute a record in our Transactions to which laymen and beginners may be referred.

Jan 1, 1892

By ALEC CROWELL

Mississippi has had oil production for only the past six years and natural gas production of minor magnitude since&apos; 1926. The search for oil and gas commenced in 1903 and 1496 wells had been drilled in search of oil and gas up to Jan. 1, 1946. As the year 1945 ended, 659 wells were producing oil and gas from 23 separate reservoirs. The production for the year was 8,353,719,000 standard cubic feet of natural gas measured on a pressure base of 15.025 lb. per sq. in. abs., 15.316,009 bbl. of oil¬field water and 19,093,766 bbl. of crude oil and condensate. Production for the year 1944 was 2,636,067,000 standard cubic feet of gas, 14,979,793 bbl. of salt water and 16,420,346 bbl. of crude oil and condensate.

Jan 1, 1946

By M. S. Miller, R. H. Mullennex

The growing need for development of thinner, more erratic, or less easily-mined coals in the Appalachian region requires more detailed analysis of conditions and factors controlling or influencing deposition of these seams. The value of depositional modeling in evaluation of such coals has been demonstrated in many recent studies and publications. Such modeling may be applied to allow prediction of factors varying from regional coal occurrence trends to very local areas of seam discontinuities but requires thorough we of all available types of data. Mapping of general depositional energies, as derived from basic geophysical and driller&apos;s logs, can be applied to specific prediction of coal occurrence, and projection of particular facies as representative of unique depositional features or conditions may prove more applicable to coal character delineation than mapping of the coal itself. Depositional modeling and trend projection may also serve as a guideline in reserve classification and confidence levels in reserve estimations.

Jan 1, 1983

By G. E. Pellissier, C. W. Mason

Tin has long been cited as offering a classic example of polymorphism, second in repute only to the allotropy of sulphul.. The notorious "tin disease," which Cohenl has studied so exhaustively in terms of the enantiotropic transformation of tetragonal white P tin to cubic gray a tin, has apparently encouraged the expectation that one or more additional polymorphic modifications might exist. The search for confirnmntion of this idea has, as might be anticipated, led to the accumulation of a body of miscellaneous evidence, much of which would probably never have been sought, or taken seriously even by its discoverers, but fur previous assumptions. The ball apparently was started rolling iii 1880 by Trechmann,2 who reported a new modification of tin (7 tin), which was brittle and found in "hard head," a highly arsenical, slaggy material produced in a certain stage of tin smelting. A mixture of two kinds of crystals was obtained from a Cornish tin furnace, and those thought to be 7 tin were studied crystallographically. The results indicated that these crystals were rhombic and of different density from the tetragonal tin prepared electrolytically by Miller. Their analysis was given as 98.7 per cent Sn, 1.3 per cent Fe, and traces of As, Sb, Bi and S. In 1881 von Foullon4 obtained similar crystals from a Bohemian tin furnace. Headden5 examined crystals similar to those of Trechmann and von Foullon and reported them to be monoclinic, but of analysis corresponding to stannous sulphide. Later, Stevanovic,~ by goniometric measurements, proved that these crystals of SnS were really rhombic. Groth7 pictures and describes both "rhombic tin" (Fig. 9, vol. 1) ant1 stannous sulphide (Fig. 84, vol. 1); their faces and angles correspond within the accuracy of measurement. Spencers in 1921 examined the above evidence critically; lie lound similar crystals from Cornish tin furnaces, proved them to be SnS, and even was able to analyze some of Trechmann&apos;s original specimens, finding high sulphur content. (Apparently Trechmann&apos;s analysis had been based on :L second lot of crystals, not described crystallographically.)

Jan 1, 1939

By G. E. Pellissier, C. W. Mason

Tin has long been cited as offering a classic example of polymorphism, second in repute only to the allotropy of sulphul.. The notorious "tin disease," which Cohenl has studied so exhaustively in terms of the enantiotropic transformation of tetragonal white P tin to cubic gray a tin, has apparently encouraged the expectation that one or more additional polymorphic modifications might exist. The search for confirnmntion of this idea has, as might be anticipated, led to the accumulation of a body of miscellaneous evidence, much of which would probably never have been sought, or taken seriously even by its discoverers, but fur previous assumptions. The ball apparently was started rolling iii 1880 by Trechmann,2 who reported a new modification of tin (7 tin), which was brittle and found in "hard head," a highly arsenical, slaggy material produced in a certain stage of tin smelting. A mixture of two kinds of crystals was obtained from a Cornish tin furnace, and those thought to be 7 tin were studied crystallographically. The results indicated that these crystals were rhombic and of different density from the tetragonal tin prepared electrolytically by Miller. Their analysis was given as 98.7 per cent Sn, 1.3 per cent Fe, and traces of As, Sb, Bi and S. In 1881 von Foullon4 obtained similar crystals from a Bohemian tin furnace. Headden5 examined crystals similar to those of Trechmann and von Foullon and reported them to be monoclinic, but of analysis corresponding to stannous sulphide. Later, Stevanovic,~ by goniometric measurements, proved that these crystals of SnS were really rhombic. Groth7 pictures and describes both "rhombic tin" (Fig. 9, vol. 1) ant1 stannous sulphide (Fig. 84, vol. 1); their faces and angles correspond within the accuracy of measurement. Spencers in 1921 examined the above evidence critically; lie lound similar crystals from Cornish tin furnaces, proved them to be SnS, and even was able to analyze some of Trechmann&apos;s original specimens, finding high sulphur content. (Apparently Trechmann&apos;s analysis had been based on :L second lot of crystals, not described crystallographically.)

Jan 1, 1939

By T. A. Lang

For permanent structure underground, where rock is not competent, support usually consists of concrete or reinforced concrete. However, temporary supports in the form of timber or steel are often needed during construc-tion. Although the history of rock bolting is relatively short—50 years— their use has become widespread in general engineering construction as well as mining. This profusely illustrated and detailed study covers a broad range in the field of rock belting: from the behavior of rock and bolts including rock properties, masses, and structure; mathematical formulae for rock bolt applications; through analysis of various operations and descriptions of the bolts themselves. Rock construction is one of the oldest of the engineering arts and its origin is lost in antiquity. From the days when early man decided that he wanted to improve the natural caves which he was using for shelter and protection or made a river crossing by placing rocks to form a ford or causeway, we have had structures made of rock. It is not too much to say that rock in situ as a structural material forms part of every major engineering undertaking. Rock bolting is one means whereby the inherently good characteristics of rock in situ are preserved and used to the best advantage and the bad characteristics ameliorated. In many cases the latter are accentuated by construction processes used. Rock bolting, as with other rock construction techniques, is only just beginning to emerge from being an art. Consequently, its theory and practice is still more descriptive than mathematical. ROCK BOLTING In underground excavations, where the rock is not competent, support is provided. For the permanent structure, this generally consists of concrete or reinforced concrete. However, support may be needed during construction before the concrete can be placed, and conventionally this consists of timber or steel support in the form of ribs, struts, and lagging. Alternatively, rock bolts may be used. Although their use dates back over 50 years, it is only in recent years that rock bolts have become widely used, not only in mining but in general engineering construction. A rock bolt is a steel bar which is inserted in a hole drilled in rock. The end away from the rock face has a device which permits it to be firmly an- chored in the hole and the projecting end is fitted with a plate which bears against the rock surface. The bolt is placed in tension between the anchor and the plate, thereby exerting a compressive force on the rock. The essential feature of a rock bolt is that it is placed in tension. This distinguishes it from anchor bars which are grouted into holes in rock, but which are not prestressed. The difference between an anchor bar and a rock bolt when the rock bolt is grouted in is analogous to the difference between the reinforcement in ordinary reinforced concrete and in prestressed reinforced concrete. The view that rock bolts only pin or nail blocks or slabs of rock which are loose to the sounder rock behind them is erroneous. Rock bolts are useful for this purpose and have been so used for a long time. However, the term rock bolting, as used here, means the designed use of rock bolts to reinforce and develop the rock around an excavation into a structural entity which can competently play its part in a structure such as a powerhouse or a mine installation. Rock bolts behave quite differently than steel ribs. They can be installed at the working face directly after blasting and within a short space of time can be exerting a stabilizing pressure on the loosened rock surface. This early installation not only partially restores loosened blocks of rock to their original unloosened positions, but also it prevents the gradual relaxation or loosening of the decompression zone behind the new rock face. In contrast, steel ribs generally use timber blocks, wedges, and lagging between the ribs and the irregular rock surface. The timber is relatively compressible, and loosened blocks of rock must move outwards an appreciable distance before any load builds up on the steel ribs. Also, the ribs may settle as the foot blocks and foundation become compressed. Hence, it may take several days or weeks before the rock has moved sufficiently to make the steel ribs carry an effective load.

Jan 1, 1961

By E. H. Fahmy, L. C. Uren

During recent years, oil producers have observed with interest the practical success which has attended the application of water as a medium for displacement of oil from its reservoir sands in the Bradford field of northern Pennsylvania and southern New York. Here, according to various authorities, additional recoveries of frorn 2,000 to 12,000 bhl. of oil per acre have heen secured by this method, after ordinary flowing and pumping. rnethods of production had practically reached the lower limit of economic operation. Notwithstanding the success which has attended the practical use of the flooding process in the Bradford field, oil producers in other regions are skeptical of its value when applied under physical conditions differing markedly from those which characterizc the Bradford field. Its usc would probably he construed as illegal in most of the oil-producing states. This general relnctance on the part of oil producers in other regions to accept the flooding process is due in large part to lack of infor-n~ation regarding the factors that influence its operation and efficiency. With the purpose of clarifying to some extent the issues involved, and of determining when the flooding proccess may or may not beeffee-tivcly ernployed, the writers have conducted a serics of laboratory exper-imentments under carefully controlled conditions, designed to indicate, the influence of various physical, chemical arid lithologic factors. These experments have not been conducted under conditions identical with those which exist at depths far below the earth&apos;s surface, so that direct quantitative comparisons with field results are not justified, hut it is believed that the experimental results at least warrant qualitative inter-pretations that may he applied to field conditions. The methods employed in the conduct of these experiments are briefly explained, and the results, together with the conclusions based thereon, arc presented. FactoRs Influencing Displacement of Oil froM SaNdS by WAteR- flooding Before presenting the experimental data, it, will he desirable to con-sider the manner in which the residual oil is retained within the oil sand

Jan 1, 1928

THE developments in construction and operation of the basic open-hearth furnace that have taken place in recent years have placed new emphasis on the vital influence played by regulation and control of the combustion system in both furnace production and furnace life. The several factors influencing flame development, such as regulation of fuel supply, air supply, air preheat, furnace draft, and furnace reversal, must be controlled closely if successful furnace performance is to be accomplished. Rugged instrumentation of distinctive design is required to sup- ply dependable information concerning operating conditions, which is requisite to proper regulation of combustion. This chapter attempts to give a practical discussion of the various features of open-hearth practice and instrumentation related to the efficient heating of the furnace, control of temperature, and protection of the furnace structure from accidental overheating. The appended references will be helpful to readers wanting a more detailed treatment of individual topics. OPEN-HEARTH FUELS The most important open-hearth fuels are listed in Table 4-1 together with their compositions and other data useful for combustion calculations. A detailed discussion of open-hearth fuels is not attempted here, but certain factors peculiar to their application to this type of process are briefly indicated on the following pages. Very often an open-hearth shop is forced by economic factors to use a fuel to which its furnaces are not very well adapted, because the general fuel-allocation scheme for the works as a whole seems to demand it. Often a variable marginal supply of coke-oven gas or tar must be consumed by the open hearth, together with another fuel such as producer gas, natural gas, or oil, to fill out total requirements. Most furnaces employ more than one kind of fuel during their useful life; however, the partial redesign

Jan 1, 1964

By E. H. Dix

All commercial aluminum contains small percentages of copper, iron, and silicon as unavoidable impurities. The purest metal obtainable commercially, special grade high purity ingot, contains a maximum of 0.50 per cent. impurities of which the usual minimum amount of copper is 0.01 per cent.; silicon, 0.12 per cent.; and iron, 0.20 per cent. This grade is too costly for most purposes. The two standard grades, Nos. 1 and 2, containing a minimum of 99.0 and 98.0 per cent. aluminum, respectively, are more generally used. Other grades of secondary aluminum often contain as high as 3 or 4 per cent. of impurities, which include 1 per cent., or more, of zinc. Specifications for high-grade aluminum-casting alloys generally allow a maximum of 1.7 per cent. for total impurities. The S. A. E. Specification No. 33, which is intended to cover alloys made from secondary aluminum ingot, gives the iron maximum as 1.5 per cent. and the maximum for silicon (including manganese and tin) as 0.75 per cent. The effect of even relatively small amounts of impurities on the physical properties of ingot aluminum is shown by the following cornparison of two lots of aluminum, which may be taken as representative of special grade and grade No. 2 ingot, respectively. AnalysEs Special Grade, Gbade No. 2, Per Cent. PeR CBnt. Copper................................. 0.01 0.32 Silicon................................. 0.12 0.32 Iron................................... 0.42 0.82 Aluminum.............................. 99.45 98.54

Jan 1, 1923