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The Library of the above-named Societies is open from 9 A.M. to 9 P.M. on all week-clays, except holidays, from September 1 to June 30, and from 9 A.M. to 6 P.M. during July and August. The Library contains about 55,000 volumes, including sets of technical periodicals and the publications of scientific and technical societies. Members of the Institute, with few exceptions, are forced to spend a portion of their time in localities isolated from sources of information. To these the Library can render valuable service through correspondence; letters requesting information will receive special attention. The Library is prepared to furnish references and copies of articles on mining and metallurgical subjects; to determine the existence of mining-maps, and to furnish general information as to the geology and mineral resources of all countries. All communications should be made as definite as possible so that the information received may be what is desired and not include collateral matter which may not be of interest. The time spent in searching for such collateral matter will be saved, and the information will be sent more promptly and in more usable shape. The members of the Institute can be of service to the Library by forwarding copies of mining-reports, maps privately issued, and similar material, which will be classified, indexed, and made available to other members. Suggestions for additions to the Library, either by purchase or personal solicitation as gifts, will be welcomed. It is hoped that members while in the city will use the Library freely, and assurance is given that most careful service will be rendered to them.

Jan 4, 1913

By Warren Smith

IT has been 5 years since the writer left the Philippine Islands and while in that country his chief work did not lie in this field, though he has visited all but one of the localities mentioned in this article. The principal field studies relating to oil were made by his colleague, Mr. Wallace E. Pratt. The writer's investigations dealt with the general stratigraphy and paleontology of the Philippines. With the exception of the investigations made by Mr. Pratt and the writer very little information on this subject is available. A number of geologists in the employ of large oil companies have visited the Islands from time to time but, following the general rule, the public has scarcely ever been permitted to learn anything of the results. The writer is indebted to the Bureau of Insular Affairs, Washington, for late information regarding recent legislation in the Islands relating to petroleum. All the known oil seeps, petroleum residues, such as ozocerite, and natural-gas emanations are associated with Tertiary sediments. The chief seeps and most promising prospects are located as follows: 1. Bondoc Peninsula (lower end), Tayabas Province, Southeast Luzon. 2. The west coast of the island of Cebú from Alegria north to, and perhaps beyond, Toledo. 3. Central Mindanao not far from Lake Lanao. 4. The ozocerite veins on the Island of Leyte in the northwestern part in the vicinity of the town of Villaba. 5. Natural gas from some deep wells in Tertiary shale formations on the eastern flank of the Cordillera and extending out under the plain on the island of Panay.

Jan 2, 1920

By A. Donald Kelmers, Forest G. Seeley, B. Zane Egan

INTRODUCTION Coal ash, presently the fifth most abundant of the solid minerals produced in the United States, is expected to become the fourth most abundant by the end of this decade (1). The production of fly ash from the combustion of pulverized coal amounted to a total of 44 million metric tons (Mt) in 1977 and is expected to Increase to 91 Mt by 1985. Coal ash, which results from the Inorganic clay and mineral content of the coal, contains several elements and thus can be considered as a mined and crushed mineral resource rather than a waste material Furthermore, potential problems associated with fly-ash disposal ponds and the leaching of potentially hazardous elements through groundwater infiltration and/or rainfall provide additional incentive for processing fly ash for environ- mental control as well as for the recovery of certain metal values. Fly ash could provide an abundant domestic source of aluminum and several other metals Aluminum is now recovered from bauxite, and over 90% of this ore is imported since domestic sources are limited and cannot meet the U.S. demand There is a close relationship between the aluminum content of fly ash and the domestic consumption of this metal (Table 1).

Jan 1, 1981

By Lawrence H. Van Vlack

The energy of the y-iron grain boundary was determined to be 850 ergs per cm2 at 1105°C. The a/a and the a/y boundaries possess somewhat less energy. The microstructures of several iron alloys are discussed in terms of the interfacial energy relationships. THE dependence of the shape of liquid interfaces upon their energies has been studied for some time.1"3 Recently, Smith' concluded that many of the microstructures observed in metals may be attributed to the energies of the interfaces between the grains and phases. While the energies of liquid surfaces have been measured by numerous different methods: only two attempts have been made to determine experimentally the energy of surfaces involving crystalline solids. Udin, Shaler, and Wulff8 used a procedure introduced by Berggren7 to measure the surface tension of solid copper. It consisted of determining the load required on a thin copper wire so that the surface tension was counteracted, and no net strain resulted. Bailey and Watkins8 sed a different technique and were able to determine both the surface tension of copper and the tension of the copper grain boundary. They measured the contact angle which liquid lead makes against a copper surface. They then calculated the above energies from the surface energy of liquid lead by using the Pb vs. Cu/CuY dihedral angle and the surface groove angle formed during thermal etching. They obtained a value of 1800 dynes per cm for the surface tension of clean copper and approximately 640 dynes per cm for the tension of copper grain boundaries. The former value was somewhat higher than Udin's value of 1500 dynes per cm. This paper includes a determination of the energy of the y-iron grain boundary. In addition, the micro-structural relationships of several other metallic and nonmetallic phases with iron were examined and an attempt was made to interpret the observed structures in terms of interfacial energy relationships. Theoretical Considerations In a three-phase material containing a solid and two liquids, there may be two solid/liquid interfaces, one liquid/liquid interface and one inter- granular interface. Liquid/liquid interfacial energies can be measured directly. Therefore, by determining the energy of such an interface and by measuring the required interfacial angles: the energies of the interfaces involving solids may be obtained.10 They may be shown schematically as in Fig. 1. The above procedure requires the following assumptions: 1—The interfacial energies are, in general, unaffected by boundary orientation, and 2— the shapes of the interfaces are unaltered between annealing and sectioning for microscopic examination. The first assumption is good to a first approximation as shown by Dunn and Lionetti11 except for a few critically orientated boundaries. Two conditions may alter the shape of a boundary upon cooling: 1—Precipitation of dissolved material upon one side of the interface, and 2—a change in volume during the transition from one phase modification to another. The former must be detected by microscopic observation. The latter may become appreciable in systems containing an interface between two liquids which solidify after annealing. However, possible movement of the two-liquid interface may be checked in the system diagrammed in Fig. 1 by measuring 8, for example, and comparing it with its value as calculated from the other interfacial angles by: tan8, C11 05 COS- o- + cos 8, cos- The choice of a suitable pair of liquids is limited by several factors. The relative values of the several

Jan 1, 1952

By J. R. Thoenen

THE Bureau of Mines has used various sizes of core barrels above 2 in. and below 10 in. in diameter to core manganese, potash, coal, brown iron ore and bauxite. The paper describes in some detail the methods and types of equipment used to obtain maximum sampling accuracy.

Jan 1, 1947

The American Institute of Mining, Metallurgical, and Petroleum Engineers, Inc, shall be composed of constituent parts as follows Section 1 Societies-The Institute shall be divided into three or more Societies as follows a The Metallurgical Society of AIME Society of Mining Engineers of AIME Society of Petroleum Engineers of AIME Other Societies may be formed within the framework of AIME or granted member¬ship in AIME as approved by the Board of Directors Section 2 Divisions and Subdivisions-The several Societies of the Institute shall consist of Divisions as follows a The Metallurgical Society of AIME 1 Institute of Metals Division 2 Iron and Steel Division 3 Extractive Metallurgy Division Any Divisions or Subdivisions which may be formed in the future with the approval of the Board of Directors Society of Mining Engineers of AIME I Coal Division 2 Industrial Minerals Division 3 Minerals Beneficiation Division 4 Mining and Exploration Division

Jan 1, 1960

By Richard R. Bains

"When l hear - I normally remember 10 percent When I hear and see - I can remember 15 to 25 percent When I hear, see, and do - I usually remember up to 50 percent" While this is not a truism in relation to each and every individual; on the average, this is the case. If we use this as a premise in training operator and maintenance personnel, then it must be obvious that we can't rely on a mere presentation, even one which includes the needed classroom participation and/or hands on work, to do a thorough job and to make this personnel totally proficient - 100 percent proficient. We have to have some other device some other means to make this a continuing process, a process wherein the people can grow in knowledge while performing their normal duties. We have to feel that the words "normal duties" are the key to the whole program. If you would ask a crusher operator what his duty is, he might say "To run this crusher so that we produce 250 tons per hour of a minus 13mm (minus 1/2 ") product." A maintenance man could say "To fix the unit when there is a problem." Both of these answers are legitimate but, they are only a part of the total picture. In order for each of these individuals to do the best job, he must know not just the specifics about the machine he works with or on - he must know the interrelation of all the machinery in the crushing circuit - how the efficiency of each machine affects the others - why a minor problem on one piece of equipment can generate a major problem for another unit which follows it or precedes it. In short, you cannot separate machine operation and maintenance from the application of the equipment in the crushing circuit - and obtaining this knowledge must be a part of the normal duty of crushing plant personnel. As an example a crusher - any crusher - is designed to crush oversize material. It is not designed to accept feed which is already at or less than the required product size. If sized material goes to the crusher, increase wear results by using the crusher as a chute or the crushing chamber can be clogged up with the fines. This latter point is particularly true with cone crushers, especially in the third (Short Head) stage of crushing. When a Gyradisc is used (fourth stage crushing) it is even more critical that the product be removed before the material goes to the crusher. The crusher cannot control this - the screen ahead of the crusher does. The screen must be of adequate size and be functioning properly to allow the crusher to work at optimum. Screening is both an art and a science. Since there are so many variables which affect the output of the screen, it is always best to have a screen which is larger than the sizing calculations dictate. The screens are the most important elements in the circuit. Without screens, specification materials cannot be made and the size of the screen will ultimately aid or hinder your ability to get the most production possible out of the plant. There is a formula available from all screen manufacturers which is designed to calculate the proper screen size. It takes into consideration the

Jan 1, 1982

By L. O. Howard

What was perhaps the first attempt at basic converting in the Southwest was made by the late Charles F. Shelby at Cananea early in 1907, when he removed the acid lining from one of the 8 by 12-ft. barrel-type converters then in use at the reduction works of the Cananea Consolidated Copper Co. and substituted a lining of one course of magnesite brick. In this shell, he blew 21 taps (about 180 tons) of matte to white metal before the brick gave out along the tuyhre line. In every case, the white metal so made was transferred and blown to copper in other converters. The cost of the lining was $700 and Mr. Shelby gave up the experiment as impracticable. No further serious effort to bessemerize copper mattes in a vessel having a more or less permanent lining of basic brick was made by any of the large copper smelters in the Southwest until some months after Messrs. Peirce and Smith had brought the question permanently before the public, and had proved it to be a metallurgical and financial success by their work at Baltimore and Garfield. Early in 1911, the Cananea Consolidated Copper Co. had in operation at its reduction works at Cananea, Mex., several 8 by 12-ft. barrel-type converters lined with magnesite brick which had previously been operating with acid linings. In the 18 months following, these converters produced 50,000 tons of copper. In June, 1912, this company installed the first of its new equipment of six stands of electrically operated 12-ft. Great Palls type converters, and shortly afterward discontinued the use of the smaller shells. In September, 1911, the Consolidated Kansas City Smelting & Refining Co. had installed at its El Paso plant two 10 by 26-ft. Peirce-Smith converters. Later, in March, 1913, one standard Great Falls type converter was added. About the time the Peirce-Smith converters were going in at El Paso, the Calumet & Arizona Mining Co. was experimenting with basic linings in 7-ft. by 10-ft. 6-in. barrel converters at its plant in Douglas, Ariz. These efforts were sufficiently successful to enable the plant to "handle the total output of copper in these small shells until the standard Great Falls converters were substituted in June, .1914.

Jan 1, 1917

By J. E. Nesset, J. A. Finch

A model of the fully-loaded condition of particle accumulation on the matrix of a high gradient magnetic separator is developed. The model accurately predicts the build-up profiles reported recently by Friedlaender et al. A powerful development from the model is that loading (volume of accumulated material per unit volume of matrix) is uniquely defined by a dimensionless group, called the loading number, NL. From direct measurements, NL proved superior to the dimensionless group proposed by Watson as a measure of loading. The fine size limit of hematite recovery is examined using NL.

Jan 1, 1980

By Auguste J. Rossi

As is well known, practically all the phosphorus of the ironores smelted in the blast-furnace passes into the pig-metal, increasing its fluidity, but diminishing its strength to such an extent that, if phosphorus exceeds a certain amount, the metal is only fit for fine castings, not required to resist strains, and it cannot be used for the ordinary purposes of good foundry-iron. No phosphorus being eliminated in the acid Bessemer process, the quantity admissible in pig-metal destined for that process must be very small, and hence the ores smelted must be strictly Bessemer ores, of which, in many districts, the supply is taxed to the utmost. On the other hand, very highly phosphoric pig, a metal of little or no value by itself, when refined by the Thomas-Gilchrist process in the basic converter, furnishes an excellent steel; but such pig-iron must be made from ores particularly high in phosphorus; and these ores are not everywhere abundant, and are much sought after for this special purpose. But there are many iron-ores containing a moderate, though still important, amount of phosphorus, which yield a pig-metal

Jan 1, 1897

By K. C. Li

ARSENIC and antimony are always grouped together by chemists, since they are both members of group V of the periodic table of elements and exhibit a general similarity in the formation of compounds. Metallurgists generally think of them as less closely related because they do not have similar uses. In metallurgical operations, especially lead and copper smelting, arsenic tends to go off as a vapor phase and collect as fume in the flues, while antimony tends to remain with the bullion. Broadly speaking, the frequency of occurrence, practical utility and the effects on associated metals of arsenic and antimony are such that the metallurgist is inclined to think of arsenic as a troublesome impurity in ores, but of antimony as a valuable constituent that is recovered either as a byproduct or through the metallurgical treatment of antimony ores. Estimating the world production of arsenic as about 40,000 tons annually, probably not more than about 200 tons yearly is produced and used in metallic form, whereas one half of the approximately 40,000 tons of antimony produced annually is metallic. ARSENIC The modern uses of arsenic differ little from ancient ones. Though it has been known from early times, its poisonous quality is almost the only one that yet finds extensive use. The shift in the past century from its utilization in poisoning people to the poisoning of insects, beginning in 1860, has not only led to a considerable increase in

Jan 1, 1953

By E. E. Brownson

THIS paper will be confined to the treatment of methods as applied in the laboratory of the Boston and Montana Reduction Department of the Anaconda Copper Mining Co. at Great Falls, Mont. As the electrolytic plant of this company operates at a current density of approximately 35 to 40 amperes per square foot when running up to capacity, the arsenic and antimony content of the anodes delivered to the, plant is of considerable importance as bearing on the purity of the refined cathodes turned out. Owing to the rather high relative percentage of antimony, it has always been the custom to determine antimony as well as arsenic in all forms of copper. Thus, anodes have been analyzed in which the antimony was about equal to the arsenic although the average shows about 2 parts of arsenic to 1 of antimony. In the refined copper the relative proportions of the two impurities vary considerably, but probably in the average are about equal. In this latter case, the percentage of the two is so small that ordinarily no attempt is made to separate them, the report of analysis showing percentage of As and Sb combined. Although rapid and exceedingly accurate determinations of arsenic may be made by means of various distillation schemes, the determination of antimony, either by itself or together with arsenic, has always been more or less cumbersome and has required a considerable amount of time. By the methods, details of which follow, the determination of arsenic and antimony, either separated as in the case of anodes or together in case of refined copper, is accomplished in 24 hr. from the time the sample is received by the chemist.

Jan 8, 1913

By J. S. Johnson, W. C. McCulloch

All phases of plant operation must be synchronized so that the A number of interruptions in the flow of material may be reduced to a minimum. In the majority of plants operating under a labor agreement, time lost during the operating shift cannot be made up with overtime. With the work week restricted to 35 hr., the ratio of productive time to total time justifies extra effort in keeping the plant operating at capacity during the productive shift. This does not apply when central plants with adequate storage are operated by multiple shifts. In such installations the problems become similar to those of any factory or mill where added units, parallel circuits, or excess capacity serve to maintain the average production during intervals of maintenance shut- down. These plants, by special agreement, may run continuously, barring mechanical interruptions. The control of plant operation is in those procedures that are practiced to obtain from the run-of-mine product a high recovery of clean coal products to meet adopted trade standards and consumer specifications at the lowest possible cost. Correlation of all factors for continuous operation requires more than mechanical perfection in the plant. The run-of-mine coal must be delivered to the preparation plant without delays and the clean coal and refuse products taken away. Power supply and water requirements must be adequate. Signal systems must be established for emergency stops and to facilitate resumption of coal flow.

Jan 1, 1943

ZAY JEFFRIES (written discussion*).-I have read with much interest Mr. Ruder's discussion of Professor Howe's paper, "The Supposed Reversal of Inheritance of Ferrite Grain Size from that of Austenite." I am yet of the opinion that my first explanation' of Mr. Ruder's samples is substantially correct. In that explanation I did not intend, however, to convey the impression that "reversed inheritance" was the general rule nor even of common occurrence but rather that." Non-inheritance" was the general rule. Mr. Ruder suggests that a " perfectly formed" grain is an indication of inheritance. The grains in my Fig. 52 are perfectly formed and in fact more nearly equiaxed than those in Mr. Ruder's Fig: C,3 yet the grains in the former are known not to be inherited but to have been formed by the partitioning of larger austenite grains. On close examination of Mr. Ruder's Fig. C the very shapes of the grain suggest partitioning. Again, the grain size (25 to 30 grains per square millimeter) is at least 10 or- more likely 20 times smaller than might be expected of the austenite from which these grains were .formed under the given time and temperature conditions. Mr. Ruder's newer results on electrolytic and Armco iron are most interesting and instructive. His results fit in. nicely with my conclusions 5, 6 and 10.4 His photographs, however, indicate that the thickness of the pieces of sheet metal are such that abnormal grain growth is promoted. He indicates that equilibrium grain size after heating to 950° C., with furnace cooling, is about the same as his Fig. 1, above. I estimate this to be approximately one-half -grain per square millimeter, or 40 times as large as I have obtained with the same material (Armco iron) after heating Y4-in. bars to 1300° C. for 2 hr. and cooling in the furnace. The effect of thickness of sample on grain size is one which needs more attention.

Jan 3, 1918

By Elmer R. Kaiser

G. A. Vissac (Consulting Engineer, Vancouver, B. C.) —Some of the data presented in this paper, in connection with cost studies of washed coals, should be clarified and qualified. Washing a raw coal down to a low ash content may mean higher losses in refuse, but the cost of the operation may be more than compensated by the increased value of the resultant product. However, careful engineering and accurate machinery are required to insure maximum profits. Washing at a low gravity separation demands a very accurate automatic process, chiefly when the small sizes of coal are being handled. Coal consumers today are buying mostly on a Btu basis, cognizant of the fact that low ash contents result in lower installation costs and in savings in handling and transportation charges. The attached Table X gives the actual balance sheets of the various cleaning operations corresponding to various ash contents for the two coals presented in the paper, using the old technique of a two-products separation. or the new technique, now commonly used in Europe, of a three-way separation made possible by new methods and new equipment. Savings in capital costs, handling, and transportation have been calculated on the basis of a delivered cost f.O.b. plant of $10.00 per ton of coal at 16.5 pct ash (actual 1953 average price reported by Consolidated Edison, N. Y.), and of $3.50 at the mine also for 16.5 pct ash coal. In both cases this corresponds to values of 126 and 4.26 per 1 pct of combustible and per ton, respectively, on delivered and on at the mine prices. As an example, the middle western coal at 16.5 pct ash, raw, washed down to 4 pct ash in a two-way process will give 53.75 pct of clean coal at 4 pct ash and 46.25 pct of refuse at 31 pct ash. The value of the losses will be 0.4625x(100—31)x0.042 = $1.34. Add the cost of washing, capital, and operation, which is $0.35. The total cost will then be $1.69. But with a three-ways separation we will have 53.75 pct of first-grade coal at 4 pct ash, 37.25 pct second-

Jan 1, 1955

By P. D. I. Honeyman, P. A. Faust

At the Miami plant of the International Smelting Co., Inspiration, Ariz., there are four reverberatory furnaces, all 120 ft. long. At present only one of these furnaces is in operation. It is operated as a wet-charge furnace, the charge being distributed for about 65 ft. down the furnace length. Usually this charge contains about 12 per cent moisture and runs 25 per cent sulfur, of which there is eliminated in the furnace from 25 to 30 per cent. The furnace is oil-fired, the fuel being burned in a battery of Cananea-type, low-pressure burners. The flame is kept short and conditions so adjusted as to obtain complete combustion within the furnace. The average furnace draft, taken through the verb arch, amounts to only 0.02 in. of H2O. Draft is purposely kept low to cut down infiltration through the flues and boiler settings, and control dampers are regulated to maintain this uniform condition throughout the charging as well as the smelting period. Hot gases discharge from the furnace uptake through a common header flue to the waste-heat boilers. The general layout and dimensions of the plant are shown in Fig. 1. Four Stirling boilers, two of class M-26 (713 hp.) and two class M-31 (850 hp.), serve the furnace. Three usually are sufficient to take care of normal operation, the fourth boiler being used as a spare when necessary. The distribution of hot gases to the various boilers is regulated by the dampers in the boiler exit flues. Normally the boilers closest to the furnace uptake would evaporate more water than do those farther away, but dampers are regulated so as to distribute fairly well the load between the several boilers. Steam from the waste-heat plant is delivered to the adjoining power house of the Inspiration company, where it is used both in the Nordberg blowing engines and for electrical generation. Steam pressures and temperatures recorded are those in the main power-plant header and are thus inclusive of all losses in about 500 ft. of 10-in. line. Steam for smelter heating and auxiliary use is taken from the main waste-heat header, is reduced to 125 lb. and distributed through separate lines. Boiler feed water is supplied by the power plant and consists of returned condensate, augmented to a large extent by make-up water

Jan 1, 1934

By Samuel Taylor

IT is customary for the president of an engineering society, in his annual address, to describe either some engineering problem with which he has beer connected or to review the work of the society during his administration. My first thought, this being the sesquicentennial year of our nation, was to review the advance in coal mining for the past fifty years, during which period I have been more or less intimately con-nected with the bituminous coal industry, and have personally witnessed most of the great changes which have occurred in methods and machinery used in the production of coal, but preparation of the requisite address would take more time than could be spared to prepare it, and its presentation would consume so much time that it .would not be suitable. The new arrangement providing for giving the presi-dent's address at the business meeting makes it more .appropriate to review the work of the Institute during the past year, together with some suggestions which appeal to me as being of advantage to the future wel-fare of the Institute, which I will try to do briefly. The work of the business office has been reviewed in the Secretary's report and it will not be necessary for me to dwell on it. Suffice it to say, it seems to be going along very well. Additional work could be done which would be to the advantage of the Institute, if we had the money with which to defray the necessary ex-pense incident to it, but I will refer to this again later. I would be derelict if I did not refer to the splendid work of the Secretary and the Assistant Secretary. Keeping in touch with all the sections, which number now about 26, and affiliated student societies which number 40, besides special committees, and represent-ing the Institute on various boards, provides work enough to occupy the Secretary's time almost exclu-sively. In addition to this the Secretary and the As-sistant Secretary have the work of editing and publishing the TRANSACTIONS of the Institute; the issuing of the magazine, MINING AND METALLURGY, in the splendid manner in which it goes out to the mem-bership is no light task and I think they should receive the commendation of the membership for this work.

Jan 3, 1927

By H. E. Gross

A plausrsle method of drilling beyond the continental shelves is set forth with limitations of the method. The continental shelves comprise the water-covered portions of land masses out to 600 ft. of water, or roo fathoms. The problems and possibilities of drilling beyond this depth are discussed in this paper. Introduction Much attention is being given the problem of developing petroleum beneath the open sea. Geophysical surveys have been made 26 miles offshore1 from the continental United States, and onco offshore ownership is established it is likely that there will be drilling for oil on the continental shelves. More than two years ago the author presented the means for drilling in deep water.2 at the fall meeting of the Petroleum Division of the AIME at Los Angeles. His concepts then were based on the use of rigid foundations suitable for drilling in water up to 600 ft. deep. The present paper suggests a method for drilling in deeper water. Possibilities and Problems of Drilling beyond the continental shelves It being conceded that because restricted deep-water portions of the hydrosphere might contain oil in commercial quantities, and that at any rate it is pertinent to know more of the nature of the lithosphere beneath the hydrosphere, the possibilities and problems of drilling beyond the continental shelves should be set forth. Drilling in open water would offer few if any advantages over drilling on land. These are: 1. The ocean transportation is available to deep-water drilling sites, and extensive pipe lines and roads are unnecessary. 2. Refinery facilities and markets perhaps are established on the near-by shore where adjacent fields on land are nearing depletion. 3. There is freedom from jungle pests and tropical diseases. 4. Competitive drilling is less likely. 5. Extensive areas attractive for development arc not yet under lease or concession. Disadvantages are great and numerous: 1. Storm hazards from wind and wave. 2. Expensive foundations, either rigid or floating. 3. Shutdown times because of weather. 4. Marine Regulations of Federal Bureaus in addition to customary regulations on land. 5. Frequent difficulty in moving men and materials to and from drilling platforms. 6. Extra precautions required in open sea. For drilling in water more than 500 or 600 ft. deep, rigid foundations2 become too costly, and floating foundations must be used, and they must meet the following requirements:

Jan 1, 1947

By H. E. Gross

A plausrsle method of drilling beyond the continental shelves is set forth with limitations of the method. The continental shelves comprise the water-covered portions of land masses out to 600 ft. of water, or roo fathoms. The problems and possibilities of drilling beyond this depth are discussed in this paper. Introduction Much attention is being given the problem of developing petroleum beneath the open sea. Geophysical surveys have been made 26 miles offshore1 from the continental United States, and onco offshore ownership is established it is likely that there will be drilling for oil on the continental shelves. More than two years ago the author presented the means for drilling in deep water.2 at the fall meeting of the Petroleum Division of the AIME at Los Angeles. His concepts then were based on the use of rigid foundations suitable for drilling in water up to 600 ft. deep. The present paper suggests a method for drilling in deeper water. Possibilities and Problems of Drilling beyond the continental shelves It being conceded that because restricted deep-water portions of the hydrosphere might contain oil in commercial quantities, and that at any rate it is pertinent to know more of the nature of the lithosphere beneath the hydrosphere, the possibilities and problems of drilling beyond the continental shelves should be set forth. Drilling in open water would offer few if any advantages over drilling on land. These are: 1. The ocean transportation is available to deep-water drilling sites, and extensive pipe lines and roads are unnecessary. 2. Refinery facilities and markets perhaps are established on the near-by shore where adjacent fields on land are nearing depletion. 3. There is freedom from jungle pests and tropical diseases. 4. Competitive drilling is less likely. 5. Extensive areas attractive for development arc not yet under lease or concession. Disadvantages are great and numerous: 1. Storm hazards from wind and wave. 2. Expensive foundations, either rigid or floating. 3. Shutdown times because of weather. 4. Marine Regulations of Federal Bureaus in addition to customary regulations on land. 5. Frequent difficulty in moving men and materials to and from drilling platforms. 6. Extra precautions required in open sea. For drilling in water more than 500 or 600 ft. deep, rigid foundations2 become too costly, and floating foundations must be used, and they must meet the following requirements:

Jan 1, 1947

By E. C. Carris

THE particular field of application of machines utilizing air cur¬rents as the primary separating medium is in the cleaning of the fine sizes of bituminous coal. Approximately 12,000,000 tons of bituminous coal were cleaned by air machines during 1940. They have not found any application for cleaning anthracite. Since the development and introduction of the first successful com¬mercial pneumatic oscillating machine for cleaning bituminous coal in 1916, by the Sutton, Steele and Steele Co., Dallas, Texas, and the Ameri¬can Coal Cleaning Corporation, formerly of Welch, W. Va., four other successful pneumatic coal-cleaning machines have been developed and introduced to the American coal-mining industry: 1. Peale Davis: "Pneumo-Gravity" machine, 1924. 2. Arms "Concentrator," oscillating table, 1924. 3. Heyl and Patterson oscillating table, 199.7. 4. "Stump Air-Flow," pulsating air jig, 19391. Out of these five developments only the Sutton, Steele and Steele, or American Oscillating, and the Stump Air-Flow Jig remain on the market. They are the predominating pneumatic coal-cleaning machines in use in the United States. HISTORY OF AMERICAN TYPE SEPARATOR The first successful American machine, the CJ table (Fig. 1) was developed by the Sutton, Steele and Steele Co. The SJ table was the first standard model designed specifically for the cleaning of coal. It was installed in the original Crane Creek plant, owned and operated by the American Coal Co. at McComas, West Virginia. This plant was designed by The Roberts and Schaefer Co., Chicago, Ill., working in cooperation with the American Coal Cleaning Corpora¬tion, which had taken over the patent rights and sale of the pneumatic separators. Eight machines were installed in this plant. They were known as the type SJ. They were 60 by 84 in., the short dimension being the width of

Jan 1, 1943