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By C. H. Hopper

DIAMOND drills have played an important part in the development of mines for many years. Recently. they have also entered the production field arid the use of diamond drills m the primary breaking of ores has become a big branch of the industry. The writer has estimated roughly that the total diamond drilling in Canada during 1942 was 5,625,000 feet, of which 2,250,000 feet, or 40 per cent, was for blast-holes. This accounts for 6,750,000 tons of ore broken, using the conservative factor of 3 tons per foot of hole. Many consider that the use of diamond drills for blast-holes is the most important advance in mine practice of the past decade, and the industry owes a great deal to the staff of Noranda Mines, Limited, for the pioneering they have done in the development of long-hole mining methods and for publishing their results. A great many mines have followed Noranda's lead. At the Waite-Amulet, Aldermac, Flin Flon, Canadian Malartic, Hoyle, and Matachewan Consolidated mines, most of the ore is broken by long-hole blasting. While the mines were developing new methods, the diamond-drill industry was developing mechanically-set bits and better machines. Through the effective use o smaller, cheaper diamonds, as well as more efficient setting, bit costs per foot are only one-half what they were ten years ago. Few people realize that a diamond bit is relatively inexpensive. The common EXT coring bit, for example, contains some 200 small diamonds, weighing altogether about 2.70 carats which, at $3.40 per carat, cost $9.20. After use, the equivalent of about 100 of these diamonds may be recovered. Therefore the true cost of the bit is only $7.00, made up of $4.60, the cost of the diamonds lost, $2.00 for setting, and $0.40 tax. The trend in machines has been toward specialization for the different classes of rock in blast-hole work. Light, high-speed machines have been developed for soft ores and higher powered machines for hard ores.

Jan 1, 1943

By R. H. Fernald

In 1900, as far as available records show, there were only two producer-gas power installations in the United States. In June, 1915, the number probably exceeded 1,000. Of this number, some 84.5 per cent comprised small plants using anthracite, and only about 15 per cent of the total number utilized bituminous coal and lignite. In addition to these, two plants used wood, and three or four used oil. In the main, however, the larger sized units are operating on bituminous coal and lignite. During the early years of these plants little success was anticipated from the use of bituminous coals and lignites, but in 1904 and 1905 it was fully demonstrated at the Government testing station at St. Louis that these fuels could be utilized to excellent advantage. However, although many producer-gas plants in daily operation are using bituminous coal and lignite, many power-plant men are still skeptical regarding the successful commercial use of these fuels.

Jan 1, 1916

By McNicol M. D

Petroleum exploration in onshore Gippsland was directed in the 1950s and 1960s towards plays in the basal Latrobe and Strzelecki Groups, but these became forgotten in the 1970s with the Latrobe play discoveries offshore. The principal explorationists of the time were Woodside Oil and Arco Ltd, who then departed the scene after drilling some 18 wells without major success. In the late-1980s successful hydrocarbon finds in equivalent age Otway Group sediments in the Otway Basin were made and in early 1990 Tyers Petroleum began investigations into Strzelecki Group prospects as applied to the onshore Gippsland Basin. Some 18 anticlines have been mapped, based on shallower coal exploration drilling in the Latrobe Group, which from seismic and gravity evidence are believed to unconformably overlie similar anticlinal structures in the underlying Strzelecki Group. Strzelecki targets of interest within drilling depth are the basal Tyers Conglomerate/Rintouls Creek Sandstone Formations which outcrop in the north of the Latrobe Valley and are analogous to the Pretty Hill Sandstone in the Otway Basin. In addition, intra-Strzelecki Group targets similar to Heathfield and Windermere Sandstone Members are also considered to be present. Good source rocks are abundant including coal seams and carbonaceous sediments of Neocomian and Jurassic age, which lie within the oil window. Seal is provided by the overlying Aptian-Albian aged volcanogenic sediments. The Tyers/Rintouls sandstones - a target in the Woodside/Arco wells, with two exceptions, were not reached. Encouraging intra-Strzelecki shows were reported in many of the wells. Basal and intra-Strzelecki porous quartzose sandstones remain one of the few untested plays left in the Gippsland Basin and, in the onshore, merit extra attention as they he within the oil window at economically drillable depths.

Jan 1, 1992

By J. J. Gusek

The Riley Pass strip mine is an abandoned uranium-bearing lignite deposit in Harding County, South Dakota, covering about 150 acres of highwalls, pit floor and mine spoils exhibiting elevated levels of radioactivity. Six reclamation design alternatives were developed, ranging from doing nothing to reclaiming to approximate original con-tour. The alternatives were evaluated for expense, site stabilization, and mitigation of public safety hazards. A comparative economic evaluation on three of the alternatives was completed for the Forest Service in selecting an alternative and substantiating federal funding requests. This evaluation included economic impacts associated with physical and radiologic health hazards, affects on recreational users, socioeconomic impacts and environmental improvement.

Jan 1, 1995

By E. D. Gardner

The American petroleum industry is supplying the present domestic demand for liquid fuels. Known reserves of petroleum in the ground, however, are limited, and the .cost per barrel of finding new oil pools is increasing. Any deficiencies of domestic production in the near future doubtlessly could be made up by imports: Dependence upon foreign oil for part of our industrial requirements is not necessarily cause for alarm, but in time of war an adequate, dependable, domestic source of liquid fuels is vital to the defense of the country. As a national defense measure, and to insure a future continuous oil supply for our economic machine, it would appear logical to take steps now to develop methods for producing petroleum substitutes within our own borders. This undoubtedly was in the mind of Congress when it passed the Synthetic Liquid Fuels Act (58 stat.190; 30 U. S. C. Sup. Secs. 321-325), Approved April 5, 1944.The title' of the Law reads: An Act authorizing the construction and operation of demonstration plants to produce synthetic liquid fuels from coal, oil shales, agricultural and forestry products, and other substances, in order to aid the prosecution of the war, to conserve and increase the oil resources of the Nation, and for other purposes. Congress authorized $30,000,000 for a 5-year program and directed the Bureau of Mines to carry it out. The part of the program pertaining to oil shale is being conducted on Naval Oil-Shale Reserves Nos. 1 and 3 (fig. 1) at Anvil Points, near Rifle, Colo.

Jan 1, 1948

By L. C. Weiner

For zinc single crystals, xo = 3o, a surface coating raises both the cleavage and yield strengths over a large temperature range. The "brittle temperature," associated with slip after completion of twinning, does not coincide with the point of intersection of the flow and cleavage curves, which is associated with twinning. A surface film has no effect on the brittle temperature, while it lowers the intersection temperature some 20°. For crystals, yn = 83o, a coating decreases the cleavage strength, making it temperature independent, as well as increases the brittle temperature or its equivalent, the intersection temperature, 20°. These observations are described on the basis of a dislocation-pile-up-at-a-barrier model for brittle fracture; in crystals x,, = 3o the number and distribution of twins play a vital role. IN a recent investigation on the effects of solid environments on the brittle fracture of zinc single crystals,' it was demonstrated that the presence of a surface film changes the cleavage strength of these crystals, either increasing or decreasing it, depending on the crystal orientation. An increase in cleavage strength of some 43 per cent was found for coated crystals oriented x, — 3o K = 28",* while a decrease of 48 per cent was observed with crystals X" = y» — 83". Moreover, these effects were found

Jan 1, 1959

By A. W. Schlechten, A. H. Larson

Equilibrium H2S/H2 ratios were determined as functions of temperature (500o to 900°C) and composition in a hydrogen-circulation apparatus. Within the composition range studied there exists a two-phase region of "Zr3S4" and "ZrS2". The upper composition limit of this two-phase region is hounded by a disulfide phase and is practically constant over the temperature range investigated. The lower composition limit of this two-phase region is bounded a "Zr3S4 " phase and varies appreciably with tem- perature. The upper composition limit of the homogeneous region of the disulfide phase is not definitely determined, but it appears to he bounded by the stoichiometric composition of ZrS2. The lower composition limit of the homogeneous region of the Zr3S4 phase could not he determined due to the extremely low values of the equilibrium H2S/H2 ratios. Various thermodynamic quantities are evaluated from the data. PUBLISHED free-energy data for the Zr-S system are practically nonexistent. Strotzer, Biltz, and Meisel1 measured the sulfur pressures for the reaction 2ZrS2(s) + S2(g) = ZrS3(s) in the temperature range 783" to 874°C. The average heat of reaction calculated from the temperature dependence of the sulfur pressure is -47 keal. It should be noted, however, that according to these investigators, the two-phase region as determined by sulfur pressure constancy under isothermal conditions extended from approximately ZrS2, 3 to ZrS2.7. From consideration of X-ray data they concluded that the homogeneous regions of the disulfide and trisulfide phases are ZrS1.8-2.0 and ZrS2.8-3.2, respectively. Hahn and coworkers2 have made a structure study of the zirconium sulfide phases. They summarized the zirconium sulfide phases as follows: the compounds ZrS3 and ZrS2 with narrow homogeneous regions, a "Zr3S4" phase with a homogeneous region roughly within the limits of ZrSl.5 and ZrSo.9, the compounds ZrS and Zr4S3, and a "Zr3S2" phase with a homogeneous region within the limits ZrSo.8 and ZrSo.5. It is noted that the compounds ZrS and Zr4S3 are only formed in the gaseous state through sublimation of a phase which has the approximate composition of the compound. This paper describes the determination of the stability of the zirconium sulfide phases by a hydrogen-reduction method in which hydrogen is circulated over the heated sulfide until equilibrium is attained. The resulting H2S-H2 mixture is then analyzed. Partial molar free energies, enthalpies,

Jan 1, 1964

By R. G. Dressler

The Federal Bureau of Mines designed, constructed, and operated a demonstration plant at Louisiana, Mo., to produce gasoline, liquid fuels, and organic compounds from coal by a modified Fischer-Tropsch gas-synthesis process. Satisfactory equipment was developed to produce and purify synthesis gas and convert it into the desired products. Coal or coke was gasified with oxygen and steam to make a gas consisting essentially of carbon monoxide, hydrogen, and carbon dioxide. Dust in the raw gas was removed by cyclone separation, water scrubbing, and electrostatic precipitation. Carbon dioxide, hydrogen sulfide, and organic sulfur were removed with diethanolamine, iron oxide, and activated carbon. The gas was passed over iron catalyst and was converted into synthetic liquids, which were then separated and fractionated into gasoline, diesel oil, other liquid fuels, and oxygenated organic compounds. A 39-day continuous run demonstrated the feasibility of the process. Addition of 3 milliliters of tetraethylead per gallon of upgraded (or finished) gasoline gave a product with an octane rating up to 90 by the research method. After a caustic wash, the diesel oil was of a superior quality; its cetane number was 60 or above.

Jan 1, 1961

By EDER DOMINGOS OLIVEIRA, Leandro Viana Teixeira, Carlos Antonio Morais, Ruberlan Gomes Silva

Special attention must be considered in the production of high-grade rare earth products, such as mixed rare earth oxalates or carbonates. In the main minerals used industrially, the rare earth elements (REEs) are finely associated with impurities like calcium (Ca), magnesium (Mg), manganese (Mn), iron (Fe), aluminum (Al), thorium (Th), uranium (U) and phosphorus (P). Most of these impurities must be removed to avoid losses of rare earth oxides (REOs) as well as to prevent product quality degradation and low operational performance in the downstream steps of solvent extraction or ion exchange. The present study aims at investigating the conditions required to precipitate REEs, either as rare earth oxalates or carbonates, from purified rare earth sulfuric liquor with low Al3+ and UO22+ concentrations and very high Ca2+, Mg2+, Mn2+, and SO42− impurity contents.

By P Moynagh

"A plan is critical but on its own it is a bit one dimensional, the three dimensions critical to success over the long-term, through changing economic, geological and management conditions are:the quality of your planning an ability to see and adapt to change a disciplined continual improvement/learning system.This paper will examine how a number of major Australian resource companies have used a commitment management system to connect the ‘theory’ embodied in plans (whether mine, project, maintenance or training plans) and immediate reality ‘practice’ as experienced by supervisors and their crews in the workplace. This paper draws on management theory embodied in management operating systems (MOS), Lean, Theory of Constraints and Six Sigma approaches to continuous improvement and a good dose of real world experience. It is embodied in the statement: ‘successful organisations are driven by a series of commitments that people make to each other and deliver on’.Citation:Moynagh, P, 2016. Everyone Has a Plan Until They Get Punched in the Mouth – Creating Trust, Commitment and Results in Tough Times, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 293–299 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

"Tell us how you got involved in mining?I was first exposed to mining at a young age, as a consequence of my dad and his passion for the industry and rock collecting. Even though he graduated with a degree in mining engineering from Washington State University, my dad spent most of his career working as a structural engineer for the Boeing Company. At the time, Boeing supported a range of employee activities and clubs, including one devoted to mineral prospecting, small-scale dredging and rock hounding. My dad was extremely active in the Prospectors Club, where as a family, we spent a good part of my youth tramping around the Pacific Northwest digging for mineral specimens and panning for gemstones and gold. On my mother’s side of the family, I had relatives that mined in Dawson City and Fairbanks, AK which left a family legacy of sorts. I loved the stories that my dad and a close buddy of his, who was a geologist, would tell about various operations and towns, as well as the wild times at the annual Northwest Mining Association (NWMA) meeting in Spokane, WA. My first recollection of ever being at a commercial operation was during a tour of the Bunker Hill Mine with my dad when I was 7 or 8 years old; this had to have been shortly before the May 1972 fire at Sunshine. That visit of the mine and processing facilities made a permanent impression on me. While I always knew there was something special about the Silver Valley, I began to understand why. To this day, I still get the same feeling when I visit historic mining districts like Leadville, Morenci, Virginia City, Butte, Silverton and Barkerville. During our summer excursions to Helena, MT to dig sapphires, we would usually make visits to Butte and watch mine operations inside the Berkley Pit and surface activities at the Kelly and Mountain Con. In high school, I did well in math and science and began entertaining thoughts of pursuing a degree in engineering. Above all, I wanted to go to a college in the West that had a good academic reputation, where I could also play football. As a 6-ft, 190-lb nose guard, my options for a Division I scholarship were pretty slim, and there weren’t that many technical schools in the Northwest that were Division II that offered athletic scholarships. As fate would have it, I was unexpectedly contacted by Marv Kay, a legendary coach at the Colorado School of Mines (CSM), and was recruited to play ball. Fortunately, I had a couple of high school friends who were already attending CSM, and I had just secured a summer internship with Asamera Minerals in Wenatchee, WA. It was as if all the stars had aligned, and, with the support of my parents, I made the decision to attend Mines. Despite the stress of getting through CSM during a period when the mining industry was in freefall, it was a great decision to attend Mines, and I’m thankful for all the opportunities, friendships, and faculty mentoring I received as a student"

Mar 1, 2019

By Worner H. K

Education has always been a topic to rouse the interest of mining and metallurgical engineers, but the recent activities of the Education Committee of the Australasian Institute of Mining and Metallurgy 1, 2, together with the moves throughout the Commonwealth to extend the field of technological education, have made the subject a very live one at the present time. The authors have felt it would be appropriate that on the occasion of the First Ordinary Meeting for 1950, in Victoria, some contribution should be forthcoming concerning the history, present status and possible future trends of mining and metallurgical education in this State. As for the past, the time approaches when there will be none having personal recollections of the beginning of Victorian mining schools or of the men who started them. As for the future, it is obvious that rapidly expanding metal-producing and metalconsuming industries will demand a greater output of competent graduates and diplomates. The era immediately ahead seems to be bristling with opportunities, but mining educators need to temper their enthusiasm for various policies and programmes with the realisation that they are helping to train men who will be leaders 15-20 years hence when the problems of industry and trials of life generally may be very different from what they are to-day.

Jan 1, 1950

The United States Bureau of Mines frequently receives requests for information regarding the details of its organization and the nature of its activities. In response to such an inquiry a series of articles outlining the work of the bureau as a whole and of its different divisions was prepared and published in the United States Daily, Washington, D. C., during November, 1929. These articles are reprinted here in the hone that they may assist in giving the public a more complete understanding of the aims and purposes of the bureau and the methods by which it is laboring for the attainment of safer conditions and more efficient methods in American mineral industries. An index of these articles, with the dates of 'their publication in the United States Daily, is given below.

Jan 1, 1930

By A. D. Schwope, L. R. Jackson, K. F. Smith

Burghoff and Blank1 have pointed out that the creep properties of hard-drawn coppers are closely associated with their individual softening characteristics and have further shown that the creep resistance of various types of copper is improved, under certain circumstances, by cold stretching. In the design of certain types of electrical machinery, it is important to have the creep resistance as high as possible; furthermore, short-time creep strength is important since in many cases stresses are large only during warming-up and cooling-down periods. In this paper, data are presented showing the effect of cold work on the short time creep strengths of various types of commercial copper under several conditions. It is shown that trends from short-time creep tests are evident at longer times. Materials Used in the Investigation The coppers used in this investigation were commercial grade and of two basic types, oxygen free high conductivity (OFHC) and tough pitch. Additions of silver in amounts of 15 and 25 oz per ton were added to each of the two coppers. The analyses of these six coppers are given in Table 1. Originally, they started as wire bars 4 X 4 X 54 in. A. square rod was made by hot rolling the wire bars to 9/16-in. rod in 8 passes. This rod was then cold drawn to 0.445-in.-diam rod and annealed for 3 1/2 hr at 1000°F. It was then cold drawn to 0.325-in. rod and again annealed at 1000°F for 3 1/2 hr. Hard square rods were then made by cold rolling to 0.257 X 0.257-in. rod. Soft wire was made from the hard- drawn material by annealing at 650°F for 3 hr. The final rolling was performed using a set of 9-in. grooved rolls revolving at 30 rpm, which produced square wires. Reductions of approximately 5, 20, 30, and 40 pct were obtained using several passes in the same direction for the large reductions. The 5 pct reduction by drawing was accomplished using a steel die having 2 parallel bearing surfaces. The die angle was 7 1/2 degrees and the wires were lubricated with a paste of ceresin wax dissolved in carbon tetrachloride. The speed of drawing was 13 fpm. Since work was done on only two sides of the wire simultaneously, it was necessary to rotate it 90 degrees each pass to insure uniform deformation. The room-temperature tensile properties of the various tempers are given in Table 2. The grain size of the an- nealed 0.257-in. wires was uniform and averaged about 0.035-0.045 mm. Experimental Procedures for Short-time Creep Tests Standard creep-test frames (Fig 1) were used for the testing. Special fixtures were designed to apply axial compressive and tensile loads to the copper wires. The compression specimens were 1 in. long and the ends were ground flat and parallel. The creep in compression was indicated by the movement of reference marks s-ratched on intersliding platinum strips attached to the moving heads of the fixture. The movement was measured with an optical micrometer fitted with a filar eyepiece on which the smallest division was 0.00005 in. The tensile creep specirriens were 4 in. long which provided ample gripping surface for the jaw-type grips. The platinum strips were attached to a one-inch gauge length of the wire and the creep measured as previously described. The single-specimen furnaces were connected to individual power and control sources. The controlling equipment consisted of Foxboro controllers

Jan 1, 1950

By W. A. Dunkley, W. W. Odell

About two-thirds of the manufactured gas supplied to the public by the gas plants in the Illinois district is cnrbureted water gas. The leading generator fuel is coke, ma.de in by-product c.oke ovens or in retorts, chiefly from eastern gas coals. During the fall and winter of 1917-18, when the demand for coke by war industries and the restrictions of the Fuel Administration in connection with the transportation of coke from eastern States made it almost impossible for many gas companies to obtain their coke requireml'nts, several water-gas plants had to use bituminous coal as generator fud. Many operating difficulties were encountered, some of which were solved more or less satisfactorily in different plants. A number of plants attacked the problem rather blindly because facilities for making tests were lacking and because technical men were too busy with labor and supply problems to study thoroughly the conditions involved or to ascertain what other plants had done with this fuel. It was therefore with the hope of assisting the gas industry during this critical period, and of promoting the use of Central District coals for gas making, that the Illinois Mining Investigations, a joint agency of the U. S. Bureau of Mines, the University of Illinois, and the Illinois Geological Survey Division undertook the, tests discussed in this paper. • This report was compiled under the auspices of a technical committee appointed by Gov. Frank 0. Lowden to promote the use of Central District coals in gas manufacture as a war measure. This committee included the following representatives of the various agencies concerned: U. S. Bureau of Mines, E. A. Holbrook and W. W. Odell; Illinois Gas Association, C. W. Bradley and R. B. Harper; University of Illinois, Dean C. R. Richards, Prof. S. W. Parr, and Prof. H. H. Stoek; State Geological Survey Division, F. W. De Wolf, G. H. Cady, a.nd W. A. Dunkley. F. W. De Wolf was chairxnan of the committee and E. A. Holbrook was secretary.

Jan 1, 1924

By J. R. Thoenen

In June 1929 the Bureau of Mines issued a 13-page information circular entitled "Mineral Wool," which was one of the first publications to present to the public Rome technical aspects of the mineral-wool industry. Since then several articles on the subject have appeared in the technical press as well as in publications of State organizations. Inquiries for information on mineral wool have continued to be received by the Bureau of Mines in large number, and in 1935 it was decided to make a field survey of the plants then producing and to collect therefrom technical data to be compiled in a paper for nubile distribution. With the cooperation of the industry, this survey was made, and Information Circular 6984, Mineral Wool, was published in January 1930. The issue was exhausted after a few months, and requests for copies continued to come to the Bureau. As opportunity arose, further field studies were made in American as well as Canadian plants. The present circular contains the essential information in Information Circular 6994 together with date from later field studies.

Jan 1, 1939

SOME notes on the works of the Electrolytic Refining and Smelting Company of Australia will no doubt be of interest to members of the Institute, more especially as much of the work is new to Australasia. As many of the members who may read this paper have not been in a position to visit works of this kind, and are consequently not thoroughly acquainted with all the operations carried on, the author has taken the liberty, in some cases, to enter into explanation which would otherwise be unnecessary. The works are situated at Port Kembla (New South Wales), about fifty miles south of Sydney, and are approachable both by rail and water. The Government has recently built a low-level jetty upwards of five hundred feet long, and intends installing at an early date an electrically operated portable crane to facilitate the handling of material to and from the boats. This will mean: a considerable reduction in the length of time that boats are laid up at the jetty. There are also under construction two breakwaters, which, when complete, will materially assist shipping operation...

Jan 1, 1910

By J. D. Miller, C. L. Lin

As the techniques and resolution for 3-D spatial analysis have advanced in the last decade, it is now possible to map in detail the microstructure of multiphase materials in three-dimensional digital space. In this regard, three-dimensional x-ray microtomography offers a unique imaging capability. Spatial resolution on the order of ten microns can be achieved with the use of microfocus x-ray generators. Recently, a state-of-the-art cone beam x-ray microtomography system has been installed at the University of Utah for the quantitative analysis of multiphase materials in three dimensions. This facility has been designed to obtain 2048 x 2048 pixel reconstruction over a 10-mm diameter, while also allowing for the imaging of somewhat larger (40-mm) objects. The system is capable of handling high-density materials, even materials having a density as high as 8.0 g/cm3. This unique, one-of-a-kind, instrument will be used to obtain three-dimensional spatial reconstruction for such applications as specific examples 3D liberation analysis, pore structure analysis of particle beds during filtration and air-void system of concrete structures. The utilization of x-ray microtomography not only will allow for quantitative analysis of multiphase systems but also allow for textural characterization and the determination of phase continuity. In this paper, we present information regarding the current use of this new facility and reviewed potential applications for the advanced analytical system.

Jan 1, 2001

By S. R. S. Sastri

By using the data of E.A. Hersam and F.C. Bond's equation for energy consumption in comminution, a method was developed to analyze the performance of industrial jaw crushers. The study showed that industrial jaw crushers are generally operated below capacity. The study also showed that industrial jaw crushers generally have sufficient installed power to operate at, full capacity. The method presented can be used to estimate the capacities and power requirements of jaw crushers.

Jan 1, 1995

By H. S. Auvil, J. T. McCartney, J. D. Davis

"INTRODUCTION It is now generally recognized that the small-scale laboratory dilatometer method of test does not give results of much utility in predicting the expansion (or contraction) of a coal in a coke oven. The carbonizing conditions in the laboratory test differ radically from those in the oven; in this test, the charge is heated through the coking range of temperature as a whole, whereas in the oven, coking proceeds by layers parallel to the oven walls as each succeeding portion of the charge goes through the plastic range of temperature and coke formation sets in. The paths of the gases and vapors and the pressures set up are different in the two methods. Furthermore, the rate of heating in the test usually is much more rapid than in the oven. H. Koppers 5/ was perhaps the first to adopt apparatus and procedure whereby the layer coking of the coke oven could be simulated closely however, the heating progressed from one side of the charge only; later he experimented with a small coke oven with a movable wall heated from both sides. It is not clear how well the results in the later oven correlated with those of the earlier small test oven, but in a comparatively recent Koppers publication a modification of the original small test oven heated from one side is recommended 6/ Altieri 7/ was perhaps the first to experiment with the Koppers type small test oven in the United States and Brown- has tested a large variety of coals in a rectangular test oven of his own design heated from the sole or floor. Subcommittee XV of American Society for Testing Materials Committee D-5 is now making a study of the various methods proposed for determination of expanding and plastic properties of coal with a view to standardization. 9/"

May 1, 1939