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By Leland O. Erdahi

Many problems have surfaced in our economy during this decade, and the mining industry has certainly had its share: huge capital outlays for environmental controls, volatile markets, double-digit inflation, inadequate capital markets, political uncertainties-plus shortages of energy, manpower, supplies, and equipment. All these and other problems have left their visible marks on the economy of our industry. Solutions are slow in coming; perhaps, in some instances, there are no right answers. However, it appears that many companies are using joint ventures to an increasing extent in efforts to reach partial solutions to some of these problems. A joint venture does present an economic alternative that should be examined-especially when trying to answer questions arising within the current economic context. The dictionary defines "venture" as an undertaking involving chance, risk, or danger. The word was originally applied to hazardous undertakings involving delivery of cargoes to distant ports and subsequent disposition of the merchandise, but it is now applied to any project of limited scope and temporary duration. When two or more entities join in such a project, it becomes a joint venture, and this is the context in which I have used the term. Joint ventures may be formed for exploration, for development of a new ore body, or for expansion of an existing operation. Each requires different approaches for negotiating and drafting the agreement governing the conduct of the joint venture.

Jan 9, 1975

By Charles E. Wait

In the use of the apparatus purchased for the new chemical laboratories of the university, no piece has given us more satisfaction, or has been a greater success, than a new still which is the subject of this paper. In the designing of this still I had two definite objects in view ; one, the utilizing of steam from the large 60 horse-power boiler used in heating the building, and the other, a provision for making distilled water with gas, when steam from the heating-plant was not available. The still is encased in wrought-iron, with a lining of asbestos, and is provided with a float which automatically regulates the flow of water from the supply-pipe. It was made for me by G. J. M?rrle, Pforzheim, Germany, and was imported by Messrs. Eimer & Amend, of New York City. It is a beautiful piece of apparatus, and the workmanship is excellent in every detail. The essential parts of this apparatus will be understood by consulting the accompanying figures, but a few words of explanation may be appropriate. The still has a capacity of seven gallons, and is made of heavy copper, tin-lined. It has a water-gauge showing the height of the water in the still, also an exit for steam, and safetyvalve, V; inlet for steam through a coiled perforated block-tin pipe; also an outlet, 0, for cleaning out the still; and there is also a heavy

Jan 1, 1895

By F. J. Budin

Steel supports are increasingly used in metal mines for junctions, chambers, and other wide openings and for semi-permanent areas such as haulageways, shaft stations, and pump rooms. Steel lasts longer-especially in wet mines and where foul air is present-and is procurable in different sizes that will carry heavier loads than any timber of equivalent cross section. The chief advantage of steel supports is that less excavation is needed than with timber support of the same strength, so that faster progress can be made. Since there is no possible way to calculate the exact weight on supports, sizes must be chosen by experience. Any adjustment and cutting of steel supports underground would be costly and time-consuming, and it is therefore advisable to cut sets beforehand at the surface workshops. This requires standardization of sets. All these problems have been recognized at Bawdwin Mines, Burma, where mining is difficult, slow, and very expensive. The lead-silver ore is very brittle, with hanging and footwall rock of unconsolidated rhyolite tuff. During the rainy season from May to October water penetrates into the mine, and where soft rock is present disintegration into a loose mass around openings can be expected. For this reason heavy 10x10-in. timber caps break quickly in drifts and crosscuts, and timber rots in a very short time. An average increase of 50 pct in both maintenance work and costs could not be avoided.

Jan 3, 1960

On June 15, Dr. E. E. Southard gave the following report to the Advisory Committee on Industrial Mental Hygiene of the. Engineering Foundation. Psychiatric social work, a new specialty in social work, was the topic of several section meetings (500-600 in attendance) at the National Conference for Social Work, held at Atlantic City, June 1-6. The new specialty was stated, by Dr. R. C. Cabot, to be the greatest single advance in medical social work since its establishment. Reports from three schools (Smith, New York, Philadelphia) indicate a good production rate of personnel, probably at least one hundred a; year, chiefly to be absorbed by hospitals, unless industrial psychiatry steps into the field. No detailed public announcements concerning industrial psychiatry were made; but private discussions elicited approval only for the program. Indications are that many non-medical social workers will decide to get additional training to go into medical social work and then to specialize in psychiatric social work and that many medical social workers will desire to specialize in psychiatric social work, with a view partly to entering reconstruction work, partly to entering industrial psychiatry. Suggestion has been made that psychiatric social workers may go into some kinds of, employment management and may look for special courses to that end. Evidence. has been brought that certain "compensated" psychopathic employees have been good (even very good) workmen: emphasis should be laid on this point to show the constructive aspect of industrial psychiatry:

Jan 8, 1919

EDMUND NEWTON, Minneapolis, Minn. (communication to the Secretary?).-In discussing the question of the deoxidation of steel and material suitable for performing this function at the end of the heat, it would seem logical also to include the question of prevention of oxidation in the steel or the formation of iron oxide, FeO. I refer to the use of manganese in the basic open-hearth and basic Bessemer processes. The advantages of high manganese in pig iron for these processes have evidently been clearly understood in Germany for a number of years, although little has been written in regard to the exact manner in which the benefits are obtained. In this country, while we make no steel by the basic Bessemer process, our basic open-hearth process is becoming more and more important. Until 10 years ago, in this country, manganese in the pig iron for this process was considered of little value and by many writers it was spoken of as a disadvantage. During the past 10 years, however, in certain parts of the United States, higher contents of manganese in basic pig have been used with considerable success, although there is apparently nothing in our technical literature to show the reasons for this trend. A German book, "The Basic Open-Hearth Steel Process" by Carl Dichmann does, however, offer an explanation. Dichmann says that if the charge for either of the above-mentioned processes contains 3 per cent. of manganese or above, satisfactory steel.

Jan 6, 1917

By Rossiter W. Raymond

The substance known as carbonite, or natural coke, has been several times the subject of comment before the Institute. The most important contribution hitherto made to the discussion is that of Dr. Henry Wurtz, of Hoboken,* who states, upon the strength of a chemical analysis, that carbonite is not a coke, but contains 14.08 per cent. of volatile combustible matter. In 1882 a mine was opened upon a carbonite seam, near Midlothian, Chesterfield County, Va., by Messrs. Jewett & Brother, of that place. The seam, which dips westerly at an angle of about 30 degrees, was struck at the depth of 137 feet with a vertical shaft, and followed on the dip 325 feet, at which depth gangways were opened north and sooth. For these statements (having made no personal examination of the locality), I am indebted to Mr. Albert Blair, of Richmond, and for the following section, to Mr. John Bladon, engineer at the mine. The section was taken in the face of the gangway, February 17th, 1883. It shows an aggregate thickness of 15 feet of "coke," of which about 5 feet were extracted by the system employed last winter. It is reported that under the "coke" seam there is a thick seam of highly bituminous coal, which has been extensively worked on a neighboring property, a little south of the Jewett colliery, the coal being sold for gas-waking. The carbonite is used for domestic purposes, and is said to burn

Jan 1, 1883

Transit A light weight, totally enclosed theodolite, especially designed for mining, has been placed on the market by Askania Werke, A. G. The instrument weighs only 41/4 lb and measures 51/8 x 71/2 in. without tripod and in a waterproof aluminum hood. It may be mounted on tripod or bracket without removing the protective hood. [ ] Standard equipment includes diagonal eyepiece rotating in all directions which eliminates need to be in line with scope for sighting and makes an auxiliary scope unnecessary for steep sights. The transit reads direct to 1 minute and may be estimated to 6 seconds by means of optical micrometer on both horizontal and vertical circles. The telescope in vertical position serves as optical plummet, sighting through an opening in the base. The instrument is shown above mounted for attaching to a pin driven in timber or rock, eliminating tripod or set-up bar in cramped quarters. The chain clamp in the lower picture is used on timber or steel ground supports. Complete with carrying case and set-up brackets, ready for use in a raise, it weighs less than 6 lb, and the protective hood remains on until the instrument is securely mounted. [ ] Accessories for increasing versatility of this mining theodolite are: tripod, electric illumination for optical micrometer and reticule, close range objective lens, and objective lens prism for sighting vertically in front of the instrument. Circle No. 1

Jan 1, 1952

By W. J. Babyak, F. N. Rhines

It has long been supposed that, regardless of the mechanism by which grain boundaries increase the hardness of a ductile metal, the effect should be linearly proportional to the grain boundary area. At the present time two methods for determining grain boundary area in an isotropic aggregate are available. The first, derived by Angus and Summers,' presumes that the grain boundary area is equal to 3vn, where n is the number of grains per sq mm in a random section through the metal. This estimate is based upon the assumption that the grains are equivalent to cubes whose faces correspond with the grains as observed in the micro-section. Measurements on copper, bronze, and a brass showed that a nearly linear relation exists between 3vn and hardness. This is illustrated, for the case of brass, in Fig. 1. The second method, developed independently by Smith and Guttman2 and by Duff in, Meussner, and Rhines,3 is absolute and employs a simple linear intercept count for measuring grain boundary area. It involves no assumptions with respect to the shape and distribution of the grain boundaries. The total surface in unit volume is 2 NL , where NL is the number of intercepts between grain boundary and unit length of a test line passed randomly through the sample. In practice, NL,, the average number of grain boundaries intercepted by unit length of traverse across a prepared microsection, is ob-

Jan 1, 1961

THE papers by G. F. Loughlin and I. A. Ettlinger discussed the distribution of formations and ore-bodies in two of the main mining districts of the Southwest. The convergence of the deeper orebodies at Cripple Creek points to their common hypogene ori-gin, as do the occurrences of the copper ores of, central Arizona. E. L. Bruce described the areas in southwestern On-tario around Red Lake and Woman Lake, another prom-ising gold district. Of special interest was a series of lantern slides showing the use of power-driven boats and of hydroplanes as means of transportation. Within a few years, no doubt; such devices will revolutionize the mining industry and reconnaissance mapping in these relatively inaccessible areas. Much interest was evinced in the paper by J. W. Finch on "Sedimentary Metalliferous Deposits of the Red Beds." It was written as a caution to people at-tempting to mine these deposits. The discussion of the chemical equations presented in the paper brought out the fact that a large amount of study of such ores is necessary before we shall be able to write equations to explain their formation. Especially pertinent were the discussions by David White as to the relation of decay-ing plant tissue to metalliferous deposits and the color of sediments; also the point brought out by T. S. Lover-ing that chemical compounds produced by bacteria may greatly affect the deposition and reorganization of sedi-mentary metalliferous deposits.

Jan 3, 1928

By W. P. Lass

Discussion of the paper of W. P. LASS, presented at the San Francisco meeting, September, 1915, and printed in Bulletin No. 103, July, 1915, pp. 1443 to 1447. ROBERT M. KEENEY, Somersville, Conn. (communication to the Secretary *).-There is not only a possibility of improvement in present methods of treatment of the byproducts of refining in the cyanide plant by the use of the electric furnace, but also in melting and refining of gold precipitate. This interesting paper by Mr. Lass shows an electric furnace in successful operation in a large plant for the treatment of by-products. Electric melting of cyanide precipitate is a cheaper form of treatment in many cases than any of the combustion methods now used because of the high cost of oil, coke or coal in many camps, while on the other hand electric power may be had cheaply, especially in a place where there is possibility of development of high-head hydro-electric plants for power purposes. Also, if the oil-fired tilting furnace is used for direct melting of the precipitate, as is the case at many small mills, a great saving in cost is made by the use of the electric furnace because of the high crucible cost in melting with the tilting furnace. A study of this paper indicates the cost of the operation approximately. Consider all the fluxes to be turned in as byproducts and coke at $18 per ton.

Jan 12, 1915

By H. J. Beattie

R. L. Stegman and M. R. Achter (U.S. Naval Research Laboratory)—In a study of the surface structures developed in the fatigue of nickel at low strains as a function of temperature, we have obtained similar results.3 As our apparatus permits fatigue tests to be conducted in vacuo, there was no masking of the surface at high temperatures by oxidation so that the structures there could be observed directly. The relatively few broad slip bands observed at room temperature gave way at 300°C to a large number of uniformly distributed and narrower slip bands. At 550°C deformation began to concentrate around the grain boundaries and progressively increased up to 800°C. In addition fatigue strength was observed initially to increase with increasing temperature up to about 600°C due to the effectively increased ductility caused by the dispersal of fatigue damage. The fatigue strength then decreased at higher temperatures as grain boundary cracking dominates. Maria Ronay, W. H. Reimann, and W. A. Wood (authors' reply)— The authors are pleased to note that R. L. Stegman and M. R. Achter reach similar conclusions from their study of surface slip on nickel. However, they would emphasize that their own conclusions are based on what is shown by study of specimens that have been sectioned and that this study also shows that surface slip is not necessarily representative of what happens below the surface.

Jan 1, 1965

Discussion of the paper of Herbert F.. Miller, Jr., presented at the New York meeting, February, 1913, and printed in Bulletin No. 75, March, 1913, pp. 409 to 413. HENRY D. HIBBARD, Plainfield, N. J.:-Looking at the illustrations, it seems to me that a furnace made with the width of port that is shown here would not be a good working furnace. The economy of brick and gas might be all right, but I do not think it would melt the steel properly. I should say that the flame would not spread out suitably to fill the whole hearth of the furnace, and there would be undue waste, and it seems to me that it would be an undesirable furnace to adopt. The question as to whether a producer-gas flame would lie down in the furnace, hugging the bottom better than the natural-gas flame, is settled, not so much by the specific gravity of the gases themselves, as by the relative temperatures at which they enter the laboratory of the furnace. We know in that case that producer gas would be lighter than a natural gas which had not been run through a regenerator and expanded four or five volumes in consequence. I would like to hear what Mr. Miller has to say about the action of the flame spreading properly over the charge to give good metallurgical results in the form of furnace which he presents.

Jan 5, 1913

The Industrial Minerals Div., of the AIME meeting scheduled for Nova Scotia Sept. 8-12, 1953, promises to be one of the outstanding gatherings ever attended by the group. Complementing the educational value of technical sessions will be the superb fishing, boating, golfing, and tennis facilities. [ ] Sponsor of the meeting is the Nova Scotia Mining Society. The Canadian Institute of Mining and Metallurgy and Industrial Minerals Div., AIME have been invited to participate. The land immortalized by Longfellow's poem, Evangeline, still contains much of the forest primeval-enough to make it a wonderful vacation spot for delegates and their families. Its scenic beauty is almost unmatched in the area north of the border. Quoting from the Nova Scotia tour book; "Nova Scotia, once known as Acadia, is 374 miles long, from 600 to 100 miles wide ... Excepting the Isthmus of Chignecto, 17.5 miles wide, the province is entirely surrounded by water, no portion being more than 50 miles from the sea . . . has 4625 miles of coastline, guarded by 356 lighthouses and fog alarms. The province is renowned for its picturesque coastline, its harbors dotted with islands, its deep valleys and multitude of beautiful lakes." A progress report on the plans for the meeting will be made monthly. Thus far, technical sessions will be held at Keltic Lodge, Ingonish, N. S. The lodge will also be the starting point for many of the field trips and social events which are in various stages of planning and development.

Jan 1, 1952

By R. A. Marriot

The steam-generating plant at the Garfield smelter of The American Smelting and Refining Co. consists of two divisions in which the boilers are classed as direct-fired or waste-heat. The direct-fired boiler plant consists of eight 330-boiler hp. type K-19 and S-I 7 Stirling boilers located in the boiler room adjacent to the power house, and two 330-boiler hp. Stirling type K-19 boilers in the reverberatory building, which formerly were connected to a reverberatory furnace but now are arranged for direct firing. All direct-fired boilers are now fired with natural gas. The waste-heat boiler plant consists of all units connected to reverberatory furnaces, and receiving heat from the exit gases therefrom. In this classification there are two 490-boiler hp. Erie City vertical water-tube boilers, and six 330-boiler hp. type K-19 Stirling water-tube waste-heat boilers. Each furnace has boilers arranged in battery setting. The boilers are directly in front of the furnace and connection is made through a short uptake and flue (Fig. 1). The Stirling boiler settings rest on concrete foundations at ground level, with the furnace uptake and flue at a low elevation. The Erie boilers are carried on steelwork some 15 ft. above ground level, and stand against the face of the uptake with no connecting flue. The constructional requirements of a larger furnace dictated this type of setting.

Jan 1, 1934

By E. P. Abrahamson

The effect of transition element binary solid solution additions upon the recrystallization temperature of titanium has been investigated. All additions, except columbium and tungsten, raised the recrystallization temperature. A correlation is obtained between the logarithm of the absolute rate of change of recrystallization temperature with atomic percent solute and the number of uuter d shell electrons attributed to the free atom of the solute element in its ground state. The work of Abrahamson, et aL.1-6 on dilute binary solid solution alloys indicated a correlation between the free atom ground state electron configuration of the solute and both the brittle-ductile transition and recrystallization temperature. It is shown in these studies that the number of outer s and d electrons in the solute are of prime importance in determining the absolute rate of change of recrystallization or transition temperature with composition. Furthermore, the limit of initial linearity (in the curve of recrystallization temperature vs at. pct solute) has been shown to be a function of the number of d shell electrons in the solute for dilute iron- and vanadium-base alloys. To date no complete systematic recrystallization study of dilute binary titanium base alloys has been made. This study together with that of zirconium base alloys 6 will provide the data for the comparison of the effect of the same solutes upon two solvents with the same number of outer d shell electrons.

Jan 1, 1962

By R. L. Stegman, M. R. Achter

R. L. Stegman and M. R. Achter (U.S. Naval Research Laboratory)—In a study of the surface structures developed in the fatigue of nickel at low strains as a function of temperature, we have obtained similar results.3 As our apparatus permits fatigue tests to be conducted in vacuo, there was no masking of the surface at high temperatures by oxidation so that the structures there could be observed directly. The relatively few broad slip bands observed at room temperature gave way at 300°C to a large number of uniformly distributed and narrower slip bands. At 550°C deformation began to concentrate around the grain boundaries and progressively increased up to 800°C. In addition fatigue strength was observed initially to increase with increasing temperature up to about 600°C due to the effectively increased ductility caused by the dispersal of fatigue damage. The fatigue strength then decreased at higher temperatures as grain boundary cracking dominates. Maria Ronay, W. H. Reimann, and W. A. Wood (authors' reply)— The authors are pleased to note that R. L. Stegman and M. R. Achter reach similar conclusions from their study of surface slip on nickel. However, they would emphasize that their own conclusions are based on what is shown by study of specimens that have been sectioned and that this study also shows that surface slip is not necessarily representative of what happens below the surface.

Jan 1, 1965

By Albert Burch

AN analysis of this subject demands a study of the theory and practice of the present system, conclusions as to its merits, and recommendations for remedying its defects if any be found. Theory of the Present Law The theory of the present law with reference to lode locations contemplates the existence upon the surface of mineral-bearing veins which have clearly marked boundaries, and which can be so readily traced that a locator may immediately mark the boundaries of his 600 by 1,500 ft. claim in such a way that the vein will pass through both of its end-lines. It also supposes that, having discovered such a mineral-bearing vein, the locator will at once post a notice upon such discovery, mark the boundaries of his location in such a manner that they can be readily traced, and from that time forward have absolute title to the ground embraced within such boundaries, as against every person except the United States. For initiating title to placer ground, the law presupposes the discovery of a valuable mineral deposit; but not necessarily in place, as in the case of lode claims; and the location must be made to conform "as nearly as may be" to the legal subdivisions of the United States public land survey. When the placer law was extended to include the acquisition of title to oil lands, no exception was made as to the necessity for the discovery of valuable mineral in advance of location!

Jan 6, 1914

By H. M. Chance

THE present value of most coal properties resides largely in the coal remaining to be mined, which thus constitutes the most important asset. The object of this paper is to discuss methods commonly used in computing the value of mineable coal. To distinguish clearly between such coal values and the values of other property, the several kinds of property values may be divided into classes; this is necessary to avoid unintentional omissions of items of importance. VALUE OF COAL RESERVES Judicial decisions prescribe, and appraisers commonly accept, current sales value as the preferred means for determining the value of transferable property. With few exceptions a property is worth the sum that can be realized from its sale by a willing seller to a willing buyer, a sale in which compulsion urges neither party, and between whom there is no community of interest to fix a value; or it is worth at least as much as a responsible buyer will offer for it. Actual sales of like property or bids from responsible buyers for the property, or for substantially like property, are the best established methods for determining values. Only in the absence of such sales or bids can valuations by other methods be entertained, and only for reasons of weight can sales values be set aside. Sales of coal in the ground, as customarily carried out through lease, under royalty agreements, are therefore the most trustworthy means available for determining the value of coal reserves.

Jan 6, 1926

By Kent E. McElhattan

Selecting efficient machinery for an underground mining operation is a highly skilled art that still depends largely on human judgment and experience. In a coal mine, for example, there is no better way to predict the results of operating with a cutting machine or a continuous miner than to go underground with a sharp-pointed miner's pick. The trained eye can detect the depth of point penetration, cleavage planes, roof and floor strata, and many other conditions impossible to determine in a laboratory. Even so, however, an entirely new set of conditions may lie unexposed just a few feet behind the solid face. The candid truth of the matter is that practically nothing is known of the phenomenon of extracting a mineral from a solid. Consequently, the selection of mineral extraction machinery and systems must be based on results obtained elsewhere under apparently similar conditions. A recent study of the problem of equipment and system analysis was conducted in the coal mining regions of West Virginia. This state was chosen for study because it afforded representative sampling. The 172 coal mines investigated ecompassed seam heights ranging from less than 30 in. to over 84 in. and covered virtually all known coal mining conditions except two. The exceptions are the extreme pitch of coal seams in the western United States and British Columbia and the "bumps" encountered in the Rocky Mountains. Both of these extreme conditions are worthy of individual study.

Jan 7, 1969

GEO. F. COMSTOCK,* Niagara Falls, N. Y. (written discussion?).¬A study of this paper raises a question on which it is hoped Mr. Stork will throw more light; that is, why does an oxygen content generated on poor melting conditions have a deleterious effect on the properties of the iron, while an oxygen content generated by the oxidation of steel scrap in the cupola is beneficial to the strength and chilling ability? In each case the oxygen is absorbed at the same time and place in the process of melting and it is by no means clear why the superiority of semisteel should be assigned solely to its oxygen absorption, when oxygen absorbed without the steel addition is admitted to be injurious. It is not apparent why oxygen caused to be absorbed by the steel addition should not pro-duce the effects of burning, sluggishness, slag inclusions, gas occlusions, etc., the same as oxygen absorbed by the iron in the cupola for any other reason, and it would seen that other factors to which he has not given sufficient emphasis must enter into the author's results. To an impartial reader of this paper, who was most favorably inclined toward J. E. Johnson, Jr.'s theory of the improvement of cast iron by oxygen, the discrepancy in the author's reasoning or statements is difficult to accept, and it is hoped that an explanation will appear in the final discussion.

Jan 11, 1919