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Discussion of the paper of L. C. Graton and Joseph Murdoch, presented at the New York Meeting, February, 1913, and printed in Bulletin No. 77, May, 1913, pp. 741 to 797. THOMAS T. READ, New York, N. Y. (communication to the Secretary *) :-At the meetings of English technical societies it not infrequently happens that, during the discussion of a paper, someone will arise to say that although he highly appreciated the material presented, nevertheless he believed it would have been better if some other phase of the question had been more highly emphasized. Assuming that this form of discussion is permissible in the Institute, I should like to reiterate the point made by Prof. A. J. Moses that conclusive proof of the identity of the minerals in question is an essential feature of the study of ores in this way. This is also expressed by Paul Krusch in his recent valuable paper 1 on the sulphide ores (in which he arrives at conclusions diametrically opposed to those of Mr. Graton), as follows : ?The diagnostic properties of the various ore minerals are known to but a limited circle of investigators." Many earlier investigators began the study of ores beneath the microscope by reflected light, but discontinued their work, in most cases, because they were unwilling to undertake the great amount of preliminary work necessary to securely establish a basis for their inferences. It is evident that Messrs. Graton and Murdoch realize that the promised later paper on diagnostic characters will be the more important of the two, but the point should be emphasized to forestall a flood of literature from other investigators who may gain the impression that the brief survey of polished specimens is a wade mecum to incontrovertible conclusions as to any given ore deposit.

Jan 10, 1913

By AIME AIME

T HE 133rd meeting of the A. I. M. E., opening in New York on Feb. 15, promises to be as successful technically and socially as any in the past. The papers submitted for the various technical sessions are unusually excellent and insure something of interest to every group. Tentative programs have already been issued, and a concise resume of the various sessions, arranged chronologically, appears on page 48. Among the many interesting technical sessions arranged, attention is directed to those of the Petroleum Division, embracing the Symposium on Production that has come to be an annual feature, and new ones on refining practice, transportation and economics. The Institute of Metals program is similarly comprehensive. It includes 15 papers, 8 on copper, 4 on aluminum and its alloys, and one each on magnesium, lead, and fatigue of metals. The Coal Committee offers as a leading contribution its report, prepared under the direction of H. N. Eavenson, giving a new analysis of the capacity of the mines and a comparison of coal with other industries. This will be supplemented by a number of other papers of especial interest to operating men, among which are "Data on Use of Loading Machines in Bituminous Mines," by Graham Bright; "Evaluation of Coal," by R. H. Sweetser; "Selection of Coals for the Manufacture of Coke," by H. J. Rose; and "Relation of Origin and State of Carbonization of Coal to Problems of Low Temperature Carbonization," by S. W. Parr. The Iron and Steel Committee has scheduled seven papers, and there will be a special session on open-hearth practice, in which will be presented the first results of the two conferences, held by the sub- committee at Pittsburgh and Cleveland. A symposium on molding sands will be a special feature of the session on non-metallics.

Jan 1, 1926

Allan Gibb, Queensland, Australia (communication to the Secretary*):—It is gratifying that Mr. Edward Keller,' who has clone so much work elucidating the principles of copper-metnllurgy, should have subjected only that portion of our investigation relating to magnetic iron oxide to anything like adverse criticism. Situated as we were on a rnining-camp, it was impossible to undertake work that would cover all the intricate possibilities connected with the materials commonly classed as matte. We therefore began the investigation on matte produced from ores that contained no other components than the sulphides of copper and iron that would be likely to enter into the composition of matte. We were, accordingly, free from ally possibility of magnetic iron oxide entering the matte, unless it were formed in the operation itself. The work done on this subject was incomplete, and the results thereof recorded as giving only negative evidence as to the absence of magnetic iron oxide. It would have been better to have left the matter open, as " not proven." The trend of the investigation was to account for the insufficiency of sulphur in matte to satisfy the requirements of ferrous and cuprous sulphides. So far as our deductions are correct, it was unnecessary to consider the (in our samples) somewhat doubtful constituent, magnetic iron oxide. The mattes that mere investigated were among those mentioned by Mr. Keller, " which scarcely show ally magnetic property." The samples showed no such property. There was no unaccountable variation in the specific gravity, which only varied, as would be expected, with the proportion of ferrous sulphide. I have had experience in smelting ores of which the gangue was a siliceous magnetite, both in blast- and rever-beratory furuace. The mattes so produced contained magnetic

Jan 1, 1908

By R. B. Harkness

Many of us are familiar with the history of oil in the Province of Ontario, but for the benefit of those who have never heard the story I will repeat it. In 185 7 J. H. Williams, of Hamilton, an old-country Scotchman, who had the advantage of experience gained from the primitive methods used for refining the oil collected at seepages in Roumania, heard of the "gum beds" along Black creek in Enniskillen township, Lambton county. He erected a small plant in the bush and refined illuminating oil, where the village of Old Springs now stands. The labor of collecting this thick ?gummy substance from the sluggish water of the creek, prompted him to dig a well, the next year ( 1858), in the hope of obtaining a greater quantity. When his excavation reached a gravel bed on top of the rock, oil, resembling "lubricating oil of commerce", rose several feet. Several of these wells were dug and his refining business flourished. The following year the Drake well, in Pennsylvania, was drilled into rock, resulting in an oil find which encouraged one James Shaw to make a similar attempt on Black creek. With a spring-pole drill he completed his well in the spring of 1861 to a depth of 160 feet, and at that depth struck a gusher that flowed uncontrolled for several days. Great excitement followed and the village of Oil Springs had a mushroom growth. The Petrolia field was discovered in 1865. Lick followed up the Thames with a spring-pole rig testing the formations along that river and discovered the original Bothwell field in 1865. During the sixties wells were drilled in many counties in southwestern Ontario.

Jan 1, 1924

By S. A. Willis

For the past several months 1 have been considering the functions of this Society and its reasons for continuance. The fact that it is now sixty years old indicates that it must have been of value and we all know that it has contributed much that was worthwhile to Nova Scotia and the Maritime Provinces. The question arises: "What is the future of the Society, and how might its activities be altered to suit present-day activities and to be of even greater value?" Let us analyse the various activities in which we are interested and determine which, if any, are of more value than others. First of all, at least once a year we have a two-day convention which constitutes a holiday for the members and their wives. This has always been well planned and has been much enjoyed. Second, there are many social and business contacts made during the meetings and interim meetings. These certainly tend toward better relations and co-operation between the various people concerned. Mine operators meet other mine operators, engineers, people from the education fields, Department of Mines, and so forth. Various sales contacts are made at these meetings which can be of value and use to both the Company selling and the customer. Third, and of greatest importance in any conference, is the exchange of ideas by the members and by authorities from outside, and the presentation of slides and drawings, or actual visits to operations. It is upon this phase that 1 wish to elaborate. These papers are not only presented to our meetings but are generally published in the C.I.M. Bulletin so that members throughout the Dominion have access to them. Many important papers describing new phases of operations have originated through our Society.

Jan 1, 1947

Joseph K. Stone, Jr. (Kaiser Engineers, Oakland, Calif.)—I would like to compliment the authors on their clear presentation of the results of their study of the pneumatic processes. We hope that the Inland Management decision to make this information available to all will induce others to release additional valuable fundamental data which they have accumulated in the field. There are two points upon which we would like to comment. In the discussion of Table VII it was indicated that the "oxygen consumptions were about the same as has been reported for other oxygen steelmaking processes". This conclusion is apparently based upon the consumption of 2100 cu ft per ton shown in Table VII. The data in Table IV also permits calculation of 2520, 2280, 2250 and 2700 cu ft per ton in heats 1 to 4, respectively. These figures are in the same general range as those reported for the Kal-Do and Rotor Processes using Thomas iron, but considerably above the following figures for four of the operating L-D Process Plants while using iron which is similar to American basic iron: Donawitz 1760 cu ft per ton Adapted from Cuscoleca' LinZ 1900 cu ft per ton Trenkler & Hauttmann2 Dofasco 1850 cu ft per ton D. O. Davis:3 In addition to the differences between the consumption of gaseous oxygen in the Inland operation and in the L-D Process, there is another closely related difference. The L-D plants for which data are cited are using approximately 1 pct ore while the authors' process used about 7 pct of sinter. Assuming 65 pct Fe in the sinter, the difference amounts to 400 to 500 cu ft

Jan 1, 1959

Edward Keller, Baltimore, Md. (communication to the Secretary*) :—The authors of this paper are to be commended for their industry and congratulated upon the many interesting results which were the fruit of their researches. While thoroughness has marked their work in general, yet on a few points in particular they have touched but lightly, for which reason, it would appear to me, they have hit wide of the mark in their respective conclusions. The work alluded to pertains chiefly to the occurrence of magnetic iron oxide (ferroseferric oxide) in copper-mattes. Because the authors find that the magnetic residue, left by the dissolved sulphides, varies largely in quantity according to the strength of nitric acid used (with potassium chlorate) in dissolving the mattes, they conclude :— "It appears, therefore, that the ferroso-ferric oxide is the result of precipitation by the oxidizing agent, rather than an original constituent of the matte." In this part of their investigation, Messrs. Gibb and Philp have ignored some well-established data,. In the first place, they have overlooked the fact that there are mattes which are strongly magnetic and others which scarcely show any magnetic property. There is nothing in their work tending to explain this variation. They Seem to have tested none of their products for magnetism. Secondly, they have overlooked the fact that magnetic iron oxide probably exists in all ore-charges in the copper-matting furnaces, and, under the given conditions, that this oxide is very difficult to reduce and to combine with silica to form slag. Thirdly, they pay no attention to the varying specific gravity of the several grades of copper-matte, which may exceed, equal, or fall below that of the magnetic oxide. These are .essential points which, I believe, clearly in-

Jan 1, 1906

By R. F. Hüttl

The restoration of surface mining landscapes requires the (re)creation of ecosystems. In Lusatia (eastern Germany), large-scale open-cast lignite mining operations generated spoil dumps widely consisting of acidified, phytotoxic substrates. Amelioration and rehabilitation measures have been developed and applied to these substrates since the 1950s. However, it is still not clear whether these approaches are sustainable. This paper reports on collaborative research work into the ecological potential of forest ecosystem development on typical minesites in the Lusatian lignite district. At first sight, pine stands on minesites along a chronosequence comprising about 35 years did not show differences when compared with stands on non-mined sites of the general region. Furthermore, with some modification, conceptual models for flora and fauna succession in forest stands on non-mined sites seem to be applicable, at least for the early stages of forest ecosystem development. For example, soil organism abundance and activity at minesites had already reached levels typical of non-mined sites after about 20-30 years. In contrast, mine soils are very different from non-mined soils of the test region. Chemically, mine soil development is dominated by processes originating from pyrite oxidation. Geogenic, i.e. lignitic, soil organic carbon was shown to substitute for some functions of pedogenic soil organic matter. Rooting was hampered but not completely impeded in strongly acidified soil compartments. Roots and mycorrhizae are apparently able to make use of the characteristic heterogeneity of young mine soils. Considering these recent results and the knowledge accumulated during more than 30 years of research on minesite rehabilitation internationally, it can be stated that minesite restoration might be used as an ideal case study for forest ecosystem development starting at "point zero" on "terra nova".

Jan 1, 2002

Dr. Wadsworth's discussion of leaching is straightforward and certainly points out some of the critical areas in regards to the fundamental aspects of leaching. I will address myself to the more practical aspects of leaching. As a couple of general comments, very fine particles are often dealt with only when necessary. In many processing applications the sands and slimes are separated with the sand portion being treated by common metallurgical techniques and the slime portion being treated essentially by any technology that will recover some of the values. Ore treatment techniques such as leach/precipitate/float (LPF) have been used in the copper industry to take advantage of leachable copper preferentially reporting to the fine fraction. The second advantage, of course, is the improved metallurgy associated with the treatment of the sand fraction. Cases can be made for sand/slime separations in the aluminum and uranium industry where most of the value reports to the slime fraction and the sand fraction is rejected In the agitated leach systems, fine particles are often the most readily attacked and leached. In dump, vat and in-situ leaching, fine particles cause considerable problems. The fines will tend to restrict the solution flow from portions of the leach feed. This either causes a significantly reduced solution flow or, more probably, the solution will channel, by-passing much of the ore. In either case the result is a decreased metal recovery from ore. The fine particles of principal concern are clays of a flat plate-like shape which can very effectively compact, swell and cause a decreased solution flow. Discrete silica grains or sulfide grains due to their shape, even though they may be very fine, will not cause nearly the problems clays and secondary precipitates can cause.

Jan 1, 1979

By L. A. Tarshis, H. E. Cline

A stability criterion for a lamellar eutectic interface was derived previously1 assuming that the wavelength, A,. of the perturbation which grows most rapidly is much larger than the lamellar spacing. A. This assumption was required to permit averaging of both the interface temperature and composition over the complicated geometry of a lamellae. If this assumption is invalid, as has been suggested.2,3 then the problem becomes too complicated to solve completely. The first of these analyses1 did not calculate the wavelength. A,. of the initially unstable perturbation. whereas the more recent analysis.' which led to a contradiction of this assumption. did not include one of the key factors for determining this wavelength. To rigorously determine the wavelength, the effect of the curvature of the perturbed interface (not considered by either of the above treatments) must be included. By omitting this term, one would be led to an incorrect conclusion regarding the magnitude of A,. but to an accurate criterion for stability as evidenced by the excellent agreement with experimental observations.' In the case of single-phase alloys. the critical wavelength. A,. for instability can be calculated from the Mullins and Sekerka4 (M.S.) analysis which includes the effects of capillarity. In the following discussion, the M.S. analysis is applied to lamellar eutectics and the critical wavelengths calculated for reasonable growth conditions in Pb-Sn eutectic alloys. In order to apply the M.S. analysis to eutectics. one may substitute i) the effective liquidus slope.1 m*. for the single-phase liquidus slope and ii) the ratio of the bulk alloy composition. C,. to the average interface composition in the liquid (Ci = CE where CE is the equilibrium eutectic composition) for the distribution coefficient to give:

Jan 1, 1970

By Warnett Kennedy

"GENUINE CONCERN for the environment is a built-in attitude of mind. If you do not have it by age 40 you probably never will. Some people speak the jargon of 'environment' and 'ecology' for political reasons, others because it feeds their need and bias toward attitudes of moral indignation or dissent. Others pay lip-service for purely business reasons. Complete reactionaries equate conservationists, ecologists and environmentalists as either 'commies' or 'pinkos'. Their real credo is the old saying, ""Where there's muck there's brass."" Those who have genuine concern for good environment are not only romantics like Thoreau but realists who sense the danger to our planet if human greed is rampant and unchallenged. The cities are in real trouble. Almost 75 per cent of the population already live in and around cities. Even mining men live in cities or bring up their children in the new 'instant' towns. The ecology of cities is the concern of all. Our distinguished guest Stewart Udall, in his book ""The-Quiet Crisis,"" quoted Thoreau in 1859 as having written ""each town should have a miniature wilderness park, a primitive forest of five hundred or a thousand acres where a stick should never be cut for fuel, a common possession forever."" Mr. Udall will be glad to know that this advice was taken in at least one instance known to me. I refer to Stanley Park in Vancouver. It is a primitive forest of 1000 acres right inside our small downtown peninsula. It remains unmanicured. This month we celebrated the completion of a seawall of 4%, miles along its perimeter. The construction of this wonderful walkway started in 1910. We are very, very proud of our park."

Jan 1, 1972

By Susumu Nagae, Hajime Ikeda

Recently, a number of mine development projects have been setback by social, economic and, environmental circumstances that had not been seen before. Many of these problems do not always originate from direct mine pollution. Typical examples of these are· conflicts between the exploration company and the local residents, sudden objections just before the development is to begin, and unexpected tightening of environmental regulations. The common background to these problems is expanding global environmental awareness. This includes complex factors ·such as the expansion of exploration to remote regions, the brisk activities of environmental NGOs, the increase of international environmental laws and, governmental policy changes. Today, the range of issues concerning mine development is widening significantly. The participation of local residents arid NGOs in the development planning, together with the company and government, has become essential for smoothly carrying out mine projects and making them more beneficial for stakeholders. Introduction The common image of the environmental problem with respect to mining is direct mine pollution, such as the collapse of tailings dams, pollution from refineries, and acid mine drainage. All over the world, the mining industry has made large investments in capital and technology to solve and prevent mine pollution, and these efforts have been making steady achievements. However in recent years, new cypes of environmental problems which are not originating directly from mine pollution are emerging frequently. Most of the problems are concentrated at the exploration stage to early stage of development, which have less impact on the environment. In the worst case, mining project may be forced to cancel and could cause serious damage to the industry because they could not collect their investment. I would like to take a general view of the examples of new types of trouble, their characters, background, and strategies against these problems.

Jan 1, 2000

By J. Juilland

Over 10 percent of the United States of America or 41 percent of the Federal lands is managed by the Bureau of Land Management (BLM) as Public Lands. The mission is to manage the use of these lands and their resources. The way in which BLM carries out its mission is being refocused under the concepts of biodiversity and ecosystem-based management for the benefit of various human needs including environmental, social and economic values. The Bureau is developing methods to integrate the renewable and non-renewable resources programs into the concepts of biodiversity and ecosystem-based management. Exploration, development and extraction of energy or mineral resources on Public Lands are affected. The statements that following the next few pages are my personal views as a scientist (economic geologist -mining technologist) who is and has been involved for the last twenty years in the multiple-use management of Public Lands. They are not necessarily the position of the Bureau of Land Management, although much of the information on which I base my views comes from my experience with the BLM. The Bureau of Land Management (BLM) manages over 10 percent of the United States (270 million acres or 108 million hectares) which is 41 percent of the Federal Lands. Lands managed by BLM are known as Public Lands as opposed to the National Forest Lands which are Federal Land Policy and Management Act (FLPMA) of 1976 which in Sec. 102 states ??that it is the policy of the United States (7) ?that management be on the basis of multiple use and sustained yield??, the mission of the BLM is rapidly refocused under the concepts of biodiversity, ecosystems, and ecosystems-based management for the benefit of the environment, human needs and socio-economic values.

Jan 1, 1994

Iron ore pellets with or without additives are commonly used as alternate charge material in both conventional and newer ironmaking processes. The performance characteristics of these pellets are normally assessed on the basis of their reducibility values, reduction strength and resistance to clustering. These properties depend mainly on the type and amount of additives and on the sintering phenomena of the pellets during firing. In the case of composite pellets (ore-coal pellets), reduction and sintering of the iron ore fines occur simultaneously. The thermodynamic and reaction mechanisms of the processes involved in the reduction of iron ore pellets with and without reductants, additives, etc., may not necessarily be identical. The reduction and sintering characteristics of pellets greatly influence the reaction mechanism and the surface morphology of the reduced pellets. The approaches in the literature to the analysis of these reduction and sintering phenomena are broadly categorized as follows: (i) empirical models, (ii) models based on kinetics, and (ill) models based on morphological changes. The relative merits and de-merits of these models are illustrated by their application to the reduction of fluxed ore-coal composite pellets. A critical analysis of the investigations that have been conducted on the reduction and sintering behaviour of such pellets is given. It is shown that, although elegant empirical models and kinetic equations have theoretical significance and can be usefully employed in elucidating the reaction mechanisms of iron ore lumps, they are sometimes not directly applicable to fluxed ore-coal composite pellets. In studies of the latter, the approach should be to correlate the morphological changes with the reduction mechanism. The paper also gives a brief account of an investigation on the reduction and sintering aspects of fluxed composite reduced iron pellets.

Jan 1, 1996

Meeting, Oct. -04, 1913.-The sum of $1,250 was directed to be sent to the International Engineering Congress, 1915, in accordance with the terns of the Institute's guarantee. It was voted to request the several Technical Committees to recommend names of their members as sub-chairmen and members of sub-committees to co-operate with the Bureau of Mines. The Finance Committee was empowered to send all members in arrears a notice that the provisions of the Constitution, by which they cease to hold the privileges of membership if their dues are not paid by Jan. 1, 1914, become operative on that date, unless the Directors vote to extend the time in each individual case. The report of the Nominating Committee, printed on page i, was accepted. It was voted that a notice to be prepared by the Committee on Increase of Membership and an application blank for membership be printed in the front of each Bulletin. The report of the Committee on Patent Law Legislation was adopted and the Committee discharged. The Budget of the Chairman and the Secretary-Treasurer of the Colorado Local Section for the balance of the present calendar year was accepted and an appropriation of $47.75 made to them. Upon the nomination of two members of the Committee on Honorary Members, backed by 13 members of the Institute who are not members of the Board of Directors, Dr. Frank Dawson Adams, of Canada, was unanimously elected an Honorary Member of the Institute. Upon the nomination of two members of the Committee on Honorary Members, backed by 11 members of the Institute who are not members of the Board of Directors, Mr. Ezequiel Ordoñez, of Mexico, was unanimously elected an Honorary Member of the Institute.

Jan 11, 1913

By Lyle D. Randen

With the environmental movement beginning in the late 1960's came a deluge of permit requirements for the mining industry. Coal mining has been one of, if not the most, severely impacted of the mineral industries as a result of the passage of the Federal Surface Mining Control and Reclamation Act of 1977. Numerous provisions of this Act and numerous regulations developed under authority of the Act are being challenged in differing levels of the judicial system across the United States. Such court cases have had varied success. Numerous other regulatory programs that are not quite as dramatic as the SMCRA have presented an unending regulatory problem for mining operators. My comments in this presentation relate primarily to the major Federal and State agencies and their legal responsibilities which we in the coal mining industry must address in order to receive authority to construct and operate surface coal mines in the State of Wyoming. A list of the Federal and State agencies one could deal with in an application is as follows: 1. Bureau of Land Management (BLM). BLM is responsible for deciding where and when to lease federally owned coal and for establishing terms and conditions for leases. BLM also has some control over surface reclamation on federal land, i.e. regrading to eliminate highwalls, covering of spoils, maximum extraction of coal to limit future disturbance, contemporaneous reclamation, etc. BLM is also responsible for designation of federal lands unsuitable for all or certain types of surface coal mining operations. 2. Geological Survey (USGS). USGS coal mining responsibilities apply only to Federal and Indian lands and concern compliance with production requirements including diligent development, minimum production levels, royalty payments and resource protection, and

Jan 1, 1983

All the TECHNICAL PUBLICATIONS and CONTRIBUTIONS published in 1933 are available at Institute headquarters, unless otherwise noted. They are also on file in many public, university and technical libraries and, when so indicated in the list, may be found in the TRANSACTIONS. Copies of the TECHNICAL PUBLICATIONS have been mailed to those members of the Institute who are registered in the different classes: A-Metal Mining; B-Milling and Concentration; C-Iron and Steel Division; D-Nonferrous Metallurgy;. E-Insti¬ tute of Metals Division; F-Coal Division; G-Petroleum Division; H-Nonmetallic Minerals; I-Mining Geology; J-Mineral Industry Education Division; K-Mining Administration; L-Geophysical Prospecting. Other members may obtain copies by writing to the Secretary. Copies of CONTRIBUTIONS may also be obtained from the Secretary's office. Additional copies are sold at the rate of 1 cent per page; minimum charge, 25 cents. Nonmembers may purchase the papers at the prices mentioned. METAL MINING TECH- NICAL PUBLI- TITLE AUTHOR MEETING TRANS. CATION VOLUME No. AND PAGE* 499-A.47 Red Ore Mines of the Woodward T. C. DeSollar New York, Iron Company at Bessemer, Feb., 1933 Alabama (11) CONTRI¬ BUTION No. 1-A The Owyhee Tunnels (16) P. R. Hines New York, Feb., 1933 2-A Sinking and Equipment of the No. D. D. Homer New York, 2 Shaft at Minas de Mata- R. H. Cromwell Feb., 1933 hambre (25) 3-A Subsidence Resulting from the Charles W. Allen New York, Athens System of Mining at Feb., 1933 Negaunee, Michigan (8) 4-A Effect of Approximately Vertical P. B. Bucky New York, Cracks on the Behavior of Hori- Feb., 1933 zontally. Lying Roof Strata (16) 21-A Selection of a Mining System (11) R. K. Warner New York, Feb., 1933

Jan 1, 1933

Report of Secretary TO THE BOARD OF DIRECTORS OF AMERICAN INSTITUTE OF MINING AND METALLURGICAL ENGINEERS Gentlemen -I have the honor to present the following report for the calendar year 1920 The activities which-seem to call for special com¬ment are THE NEW FORM OF MAGAZINE MINING AND METALLURGY appeared every month during the calendar year and has been developed until it contains some ten departments It has brought forth more commendatory letters than have been received at headquarters on any other subject throughout the year Less than a dozen letters unfavorable to the change have been received, and the indications are that the magazine has met a want deeply felt, especially by members distant from headquarters The technical papers printed by the Institute are published in abstract in the magazine and opportunity is given to members who desire them to receive full copies of any or all papers published The Bound Volumes, as usual, contain all the papers in full and discussions thereof FINANCES The greatly increased cost of paper and printing has put a tremendous burden on the Institute's finances, since the dues of $12 per year are only 20 per cent greater than the members paid when the Institute was founded forty-nine years ago This has resulted in a temporary deficit, similar to that encountered by many of our sister engineering societies The fact that our Institute has lower dues and gives more in the way of publications to its members than any other of\the national engineering societies has rendered the situation more difficult for us MEETINGS The Annual Meeting in New York, the Field Meeting in the Lake Superior District, the meeting of the Petroleum and Gas members at St Lours, and of the Institute of Metals Division in Columbus, Ohio, have all been described in full in the magazine

Jan 1, 1923

By John B. Hastings

CHIEF among the varied problems facing the mine-manager is that of vein-structure and origin, which is highly important as a guide to successful discovery and development. If metalliferous deposits can be traced to the intrusion of waters along definite lines, then is there something tangible for him to study. But when he is told by a geologist that metalliferous deposits are due to some other cause, like magmatic differentiation, while not perhaps discouraged, he is impressed with a vague sense of new worlds to be conquered. In 1897, while manager of the War Eagle mine at Rossland, B. C., where, previously, the ore-bodies had not been supposed to occur as veins, I suggested to visiting members of the Canadian Geological Survey that, perhaps, the structure of the pyrrhotite-bodies of that mine, which had been proved to occur along well-defined fractures, might throw some light on the similar deposits of Sudbury, then held to be basic aggregations from the original magma. Later investigation has at least provoked discussion of this last deduction, questioning its correctness and suggesting that, perhaps, the deposits are actual veins. The following extract from a paper by J. E. Spurr 1 is quoted, because it sets forth Mr. Spurr's theory of the quartz-occurrences of the Silver Peak mines, which will be discussed in this article. It also graphically describes the attendant geological features. '' The Drinkwater group of mines, which is the most important part of the Blair gold properties, and which has produced practically all of the million dollars' worth of ore, as above stated, may be taken as typical of the gold-veins which, though widespread and numerous, show a wonderful similarity of character. On the surface two adjacent veins outcrop, the Crowning Glory and the Drink-

Jan 1, 1913

By Paul M. Tyler

YEAR after year, the kaolin industry of the United States has been setting new production records and making better products. High-grade paper, pottery, and rubber clays are produced in this country mostly in the South. Georgia alone contributes over 70 pct and South Carolina almost 20 pct of the total domestic output. Residual kaolin is mined in North Carolina, highly plastic but naturally sandy Tertiary (Eocene) potting clays are worked in north central Florida, and good white clays are produced in several other states, but the main sources of kaolin or china clay have been numerous deposits in the Tuscaloosa (Upper Cretaceous) formation. This formation of generally sandy sediments is called the Middendorf member in older geologic reports and corresponds in age with some of the New Jersey clays. As shown in fig. 1, it crops out almost continuously in a generally southwesterly direction across South Carolina and Georgia and into Alabama. Clay is mined from this formation in all three states but the principal producing centers lie within about 10 miles of a straight line drawn between Aiken, S. C., and a point about 10 miles south of Macon, Ga. The white kaolins of the South were recognized and used prior to the Civil War but suitable treatment processes were not introduced until World War I when imports, chiefly from England, were curtailed. Although imports of high-grade clays were resumed after 1918, the domestic industry managed to treble its prewar production record during the early 1920's and has continued to grow. Whereas the 1909 to 1913 average total production in the United States was only 132,104 short tons valued at $705,352 f.o.b. mines, the output in 1948 was 1,568,848 tons worth $19,756,738.

Jan 6, 1950