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By Thomas T. Read

THE benefits derived from stabilization of industry that might possibly be attained through some scheme of centralized economic planning have been much discussed of recent months, and opinions on the subject range from those who believe that some agency like the War Industries Board would be practicable to create and wholly beneficial in effects, to those who are equally convinced that none of the suggestions so far advanced are at all practicable, or likely to be productive of more of good than of evil. The discussion has been on the general topic, but-many of those who have written or spoken on it have introduced economic problems of the pinera1 industry; for example, Newton D. Baker, who referred to the coal industry in his address on economic planning at the Williamstown Institute of Politics on July 31, and then went on to say, "Industrial progress is made by the development of new things, but new things upset the equilibrium of any plan. Who could have planned the industrial effects of the development of the railroads, or the economic changes which you have seen attend the development of the internal combustion engine. Obviously, unless we are prepared to put world economics in a strait-jacket and, like the encyclopedists, write its full history on the theory that further progress is impossible, no such plan could be made for nations which are forging ahead as is entirely rational for nations which are still catching up."

Jan 1, 1931

By Arthur Phillips

THE study of anisotropy in metals has been greatly stimulated in recent years by the rapid development of X-ray methods for determining the crystallographic relationships of wrought and annealed materials. Prior to this time the knowledge regarding the directional properties of commercial alloys consisted almost exclusively of observations of a practical nature made during the fabrication of metal objects, supplemented by a limited number of mechanical tests on specimens cut at various angles to the direction of working. Such observations clearly indicate that the common methods of cold-working metals cause both a crystallographic and a mechanical fibering varying in character and degree according to the nature and extent of the deforming process. Even after annealing, following certain not too well known combinations of reductions and anneals, a preferred orientation may exist, thereby constituting a residual fiber effect sufficiently pronounced to manifest directional properties. With the application of the X-ray the experimental horizon was extended chiefly because the study of anisotropic metals promised to offer direct and quantitative evidence regarding the involved mechanism of fragmentation and plastic flow. As a natural consequence the intensive studies in this direction have yielded a vast accumulation of data of ultimate potential value. Unfortunately, however, as is commonly the case in entering a virgin field of experimentation, many of the data cannot be molded into complete and coherent form because of the many unrelated conditions of the experimental projects. Again, the results of the study of single crystals have been rather naturally but at times indiscriminately applied to polycrystalline metals. Furthermore, sweeping statements have been made regarding the behavior during working and annealing of metals and alloys, entirely on the basis of similarity in lattice arrangement. There is abundant reason for believing that relatively small concentration variables, differences, in magnitude and distribution of applied stresses, and the character of associated annealing treatments may in some cases greatly influence the mechanics of flow and consequently largely determine the final structural characteristics of the metal.

Jan 1, 1932

THE first mention of the mining and use of coal in the Pittsburgh district refers to the mine under Duquesne Heights that furnished coal for the garrison at the fort at Pittsburgh in 1760. Coal had been dug and used as fuel just outside of Brownsville, Fayette county, in 1759, but this was not a regular mine as the opening was in an outcropping. Maps of Ohio in 1770 showed "Cole Mines" at various points. The Penns purchased all the coal south of Kittanning in southwestern Pennsylvania from the Chiefs of the Six Nations for a reported price of $10,000. During the Revolution, coal from Herron Hill, Minersville, and Coal Hill, all within the present city limits, was used in Pittsburgh. There is today one custom pit opened in Coal Hill (Duquesne Heights). The first steam engine was set up in Pittsburgh in 1794 and used coal as fuel. The first mine in the Youghiogheny gas district was opened in 1796. In 1803, the first shipment of coal by water was made from Pittsburgh down the Ohio river and landed at Philadelphia, where it sold for approximately $9.50 per ton. The mines along the Monongahela were naturally the first to be opened. With the completion of locks and dams in 1844, permitting slack-water navigation, the industry began to thrive. The No. 8 field of Ohio and the Fairmont region of northern West Virginia were opened in the period 1840 to 1855. From that time on there has been a continuous development of the coal resources of this district, until at present-productive capacity is enough to supply 30 per cent. of the country's needs of bituminous coal. The original method of working the Pittsburgh seam was to drive under cover at some .easily accessible point on the outcrop with a single entry, usually 1 1/2 yd. wide. Rooms or gangways were turned to the

Jan 10, 1926

By Carle R. Hayward

ATHOUGH there are signs of improvement in the lead industry, conditions are still far from what we have been accustomed to call normal. There has been little to stim¬ulate research and those responsible for the finances of the companies have been inclined to discourage expenditures except where need was urgent or the prospect for immediate returns bright. In spite of this fact, improvements have been developed here and there which will be available as business conditions become adjusted. No publicity is allowed at present. The rising price of silver has had a tendency to increase the production of lead from argentiferous ores but the greatest interest continues to be in the secondary field. Practically all lead plants situated near large centers of population are treating scrap materials, particularly battery plates, the quantity of which is increasing with the improvement in automobile sales.

Jan 1, 1936

By H. E. Doerr

THE writer has been unable to find much information relative to tests made to determine the effect of forging on the specific density of steel. The opinion, however, among men engaged in the business, seems to he that forging greatly compresses or consolidates the steel. While such is doubtless the case with spongy or porous steel, the following experiments indicate that there can be little or no change in the density with steel initially free from cavities: Ten ingots of basic open-hearth steel cast as shown in Fig. 1 were used in the experiments. All the specimens were 0.53 carbon with all other elements the same, the analysis being determined from drillings taken midway between the center and outside of the upper end, as shown in Fig. 2. The specimens were selected from over one thousand ingots so that the tests could be comparative for the work done in forging only, but no two of the ingots were cast in the same heat. Each ingot remained in the mold approximately 30 min., when it was removed and air-cooled. About 12 hr. later, when the temperature had been reduced to approximately that of the surrounding atmosphere, the head was discarded and the ingot heated in an oil furnace to approximately 2250° F. (1235° C). Approximately 1 min. was required to forge under the steam hammier to 1 ¼ in. (31.75 mm.), rough diameter, as shown by the dotted lines in Fig. 2. All ingots were allowed to air-cool after forging. Cylinders ½ in. (17.7 mm.) in diameter and ½ in. high were then turned from the forged and unforged parts of the ingots and numbered. The ten pairs of specimens were submitted to Louis E. Endsley, Professor of Railway Mechanical Engineering, University of Pittsburgh; A. N. Talbot, Professor of Applied Mechanics, University of Illinois; L. Z. Slater, chief chemist, Scullin Steel Co., St. Louis, Mo. No in-formation was furnished as to which specimens were forged or unforged and each laboratory used the same specimens, submitting the average of three independent determinations, a tabulation of which is shown in the accompanying table in which the laboratories are designated by

Jan 1, 1919

Edgar Hall, Silverspur, Queensland, Australia (communication to the Secretary*):—Dr. Douglas has written on this subject before, and his influence has had a powerful effect on the eide of freedom among the' younger generation of engineers. Moreover, it is not the first time that he has attributed the decline of the copper-smelting industry in Swansea to the secrecy maintained by the firms there engaged in smelting-operations. In this latter statement I think his conclusions are open to criticism. Whether the firms mentioned have suffered by their secrecy is their own business—I hold no brief for them ; but that the decline of the copper-industry at Swansea was inevitable seems to me to he proved conclusively by Dr. Douglas's own writings. In his paper on The Copper Situation,' Dr. Douglas says : "In comparing iron and copper mining,...it must be remembered that 2 tons of average iron ore from the most prolific source now available ... will make 1 ton of metal; whereas from 33 to 75 tons (say an average of 50 tons) of copper ore must be mined to produce 1 ton of copper." And further: "Last year's production of iron was made from approximately 50,000,000 tons of ore. Our copper mines, to yield a production of 900,000,000 pounds, must have handled approximately 22,000,000 tons of ore, or nearly half the quantity raised from our iron mines." Is not this the key to the whole situation ? In transporting the 50,000,000 tons of iron-ore, 25,000,000 tons of the metal iron were carried so much nearer to the market, but the transportation of 22,000,000 tons of copper-orc would have carried only 450,000 tons of the metal copper nearer to its ultimate destination. The small percentage of copper available in its ores makes

Jan 1, 1909

By Michael D. Martin

Pima Mining Co., managed and 50% owned by Cyprus Mines Corp., with Union Oil of California and Utah Construction and Mining Co. sharing equally in the remaining 50%, is a medium-sized open pit copper mine situated in the very active Twin Buttes mining district, 22 miles southwest of Tucson, Ariz. In 1965, a three-part paper described Pima's growth from 3,000 tpd (tons per day) in 1957 to 18,000 tpd nine years later. Within months of the completion of the last stage of this sixfold expansion, studies were being wound up on a further major expansion, this time to 30,000 tpd. This expansion is now a reality. Details of the enlargement of the crushing and concentrating plant have already been covered in a recent paper, and the present paper will cover pit engineering studies, equipment selection, and current operating practices. Key factors in top management's decision to go ahead with the latest expansion were: (1) a substantial increase in ore reserves coupled with an appreciable decrease in grade, (2) a generally favorable outlook for copper prices, and (3) better than expected performance by mine and mill equipment purchased for the expansion to 18,000 tpd. For the pit design studies, particular attention was paid to pit stability, a problem area at times in the past, and to the location and grades of the final ramp systems. In drawing up the long-term mining schedule, the attitude of the ore, with the higher grade material lying deeper, was a critical factor and considerable stockpiling of lower-grade material in the early years had to be accepted in order to keep the annual grades close to the average of the orebody. The expansion called for major purchases of mine equipment in order to gear up the mine for delivery of 30,000 tpd to the concentrator. In general, equipment chosen was of types already proven at Pima, al- though there were some exceptions to this practice. One of these excep-

Jan 1, 1969

By Laurence Hicks

CONSIDERATION of the past work on the subject of the diffusion of chromium into iron suggested that additional information might be given by the use of X-ray spectroscopy in following the concentration changes through the diffusion zone. Grübe and Fleischbein1 packed rods of electrolytic iron in a mixture of alumina and chromium. These specimens were heated in an atmos-phere of purified hydrogen for varying lengths of time. After treatment the specimens were examined metallographically and showed the usual structure, consisting of a border of radially oriented columnar grains ending in a sharp boundary line. Reference is made to the fact that etching with certain reagents will attack only the material inside the border of columnar growth and also to the fact that polishing seems to develop a ridge at the position of the boundary between the etched and unetched areas. By chemical analysis of thin layers turned off on a precision lathe, the authors were able to obtain depth-concentration curves. These curves, reproduced in Fig. 1, show that 'in most cases a pronounced change of slope occurs, corresponding to the position of the boundary of the columnar grains. In a later paper Grübe extends his work to other systems which show the same characteristics.2 He concludes that the reason for the break in the curve is that a hindrance of diffusion occurs at the place where the regularly oriented grains of the diffusion zone meet the random grains of the interior portion, on the assumption that the diffusion velocity in one direction in a grain may be greater than in another direction, and that the grains in the diffusion zone orient themselves so as to give the maximum diffusion rate. Kelley3 points out that Grübe has failed to note that the boundary line does not consistently cross all grains and

Jan 1, 1933

By Spruille Braden

My attendance at this seventy-fifth Anniversary banquet of the A I M E is for me a homecoming, It means renewing associations with old friends, breathing again 'the invigorating mining atmosphere in which I was born and reared, and being among those who remember with affection and esteem the man from whom I inherited a name so intimately linked to-the mining profession Tonight, like a prodigal son strayed from mining into the far countries of diplomacy, I return, to eat and be merry over the fatted calf on this pleasurable occasion , While there is no riotous living in modern diplomacy, you are no doubt convinced that neither did I suffer a mighty famine in those far lands When I entered the Foreign Service, a few mining friends, viewing diplomats as sartorial perfectionists, or "striped pantsers" preoccupied with the art of cookie pushing, no doubt thought me a lost soul Conversely, some of my new colleagues at first looked upon me captiously and later as a reformed character, because they believed all miners to be rough customers, attired in muddy boots and given to direct action and equally direct or even explosive speech In point of fact, these two professions have much in common I do not have in mind the parallel cynicisms that "a miner is a liar with a hole in the ground" and "a diplomat a man sent abroad to lie for his country " I do

Jan 1, 1947

Conservationists have launched an attack on the mining law of 1872, accusing it of permitting the min- ing industry to rob the public and despoil the environment while doing it. Michael McCloskey, executive director of the Sierra Club, and one who has made known his opposition to the law said, "environmentalists are unified in their agreement that repeal . . . is one of conservation's most urgent tasks . . . ." Charles H. Callahan, executive vice president of the National Audubon Society, paralleled McCloskey's sentiments, calling the law a "disgrace" and a "give-away." In his opening statement before the Senate Interior Committee, Chairman Henry M. Jackson (D-Wash.) said that legislation pending before the committee would put the hard rock minerals under a leasing system as is the case with oil and gas.

Jan 1, 1971

By William Kranz

Discussion of the paper of WILLIAM G. KRANZ, presented at the San Francisco meeting, September, 1915, and at the New York meeting, February, 1916, and printed in Bulletin No. 101, May, 1915, pp. 927 to 930. J. W. RICHARDS, So. Bethlehem, Pa.-At the present time I believe there are 35 electric steel furnaces under construction in the United States, and many more in operation. The United States Steel Corporation, for example, is putting up for one firm a plant of eight electric furnaces. The principal increase in use of the electric furnace at the present time is based on its superiority for making steel for shrapnel and for munitions of war. I understand that electric steel has been found far more reliable and suitable than ordinary steel for these purposes in Europe.

Jan 5, 1916

According to published reports, controlled production from the Masjid-i-Sulaiman and Haft Kel fields for the year 1934 was as follows: No new development of major importance in either of these areas is reported. Owing to the increasing- demand in North Iran, particularly for gasoline and kerosene, it has been arranged that this market shall in future draw its supplies from a newly constructed refinery at Kennan-shah. This refinery is connected by a 3-in. pipe line, 145 miles long, with the Naft-i-Shah field, on the borders of Iraq and Iran. The crude oil will pass through a topping plant at the field and the products will be stored and pumped to the Kermanshah refinery in such proportions and quantities as are demanded by actual market requirements.

Jan 1, 1935

The American Institute of Mining Engineers, the American Society of Civil Engineers, the American Society of Mechanical Engineers, and the American Institute of Electrical Engineers have established the . Engineering Societies Employment Bureau under the management of their Secretaries. One of the purposes of the Bureau is to keep in touch with all engineering firms with a view to supplying them with desirable men. Plans are under way to assist in placing men who are retiring from the government service. The Bureau is not intended to be exclusively for the benefit of unemployed members, of the Founder Societies; non-members who are introduced properly will be registered. Information, registration forms, etc., may be obtained from the office of the Bureau, Engineering Societies Building, 29 West 39 Street, New York, Room 903.

Jan 1, 1919

G. K. BURGESS,* Washington, D. C.-In the service tests, the Advisory Committee on Aeronautics considered it highly necessary, particularly for seaplanes, to find out whether or not it was necessary to paint exposed parts; reports have been obtained but have not been pub-lished at the present time. Investigations were carried on at three Navy Yards. On just a hurried examination, the inspection was made about two weeks ago and the results are now being digested an examination shows that the aluminum alloys, whether painted or unpainted, stand up very well. It apparently is not necessary to paint, which, of course, is a very important item in the question of the weight of seaplanes. We will be able to report on that, I expect, probably at the next meeting.

Jan 12, 1919

FRANCIS T. OMENS, ? Watsontown, Pa. (written discussion§).-In the second paragraph, Dr. Thwing mentions the various stages through which clay ware. must pass but he does not analyze the third stage, oxidation, suffficiently. There are two elements to dispose of in a great many, of the shales that must he burned; these elements are carbon and sulfur. Dr. Thwing speaks' of the carbon, but intimates that it is safe to have a temperature of -800° C., which we find to be rather dangerous on a great tiffany shales. With. one shale that we handle, we cannot go above 535° C. until we have passed this particular stage. At 800° C. the sulfur will begin-to pass off and it is very necessary that plenty of air be ad-

Jan 11, 1919

The manpower and time involved in primary blasthole stemming at Kennecott Copper Corp.'s Bingham Canyon mine have been reduced considerable through the use of a mobile stemming machine invented y three mine employees. The patented machine, developed 2% years ago at an estimated cost of $5000 for two units, is the brainchild of Thomas R. Carlson, mine plant superintendent; Alvin J. McIntosh, drilling and blasting engineer; and Jay K. Buehler, field repair general foreman. According to McIntosh, the machine has been well received by the mine employees, who have been relieved of the tedious task of hand shoveling drill cuttings into the blastholes. It is estimated that the stemming machine has saved the mine approximately $25,000 per year in overtime and regular labor costs.

Jan 12, 1976

By Hugh P. Tiemann

The desirability of employing the centigrade scale for the measurement of temperatures is becoming more and more recognized in this country, particularly in view of the fact that this scale is used almost exclusively in technical papers and publications—exclusively in those published in French or German. There are, however, a large number of factories and laboratories which still employ the Fahrenheit scale. It therefore frequently becomes necessary to convert one into the other and the accompanying chart (Fig. I) has been found very convenient for this purpose. The formulas for conversion follow: (1) °F. = 9o /5+ 32 (2) oC = 5 (oF - 32 ) (1) 100° C X 9 900/5 =180 .'. 180 + 32 = 212° F. 5 (2) 5 (212° F - 32) = 5 X 180 =100o C 9 9

Jan 1, 1916

By A. T. Miesch, L. B. Riley

An error occurred in the preparation of Fig. 3, p. 249, of Basic Statistical Measures Used in Geo-chemical Investigations of Colorado Plateau Uranium Deposits. This figure shows the relation of the arithmetic mean: geometric mean ratio to the geometric deviation. Curves for the cases where n, the number of samples, is 100, 10, and 5 are too high with respect to the ordinate. The error is negligible at low geometric deviations, but becomes increasingly greater wi,th higher values of geometric deviation. Arithmetric mean values in Table I1 are not effected by the errors in Fig. 3. The authors will endeavor to supply copies of the revised curves on request; write to: A. T. Miesch, Geologist, Branch of Radioactive Materials, U.S. Geological Survey, Bldg. 25, Federal Center, Denver 25, Colo.

Jan 1, 1962

By N. P. Weymont

A first step towards using advanced control and optimization techniques at Kaiser Aluminum's Baton Rouge Plant has been the decision to utilize digital process control equipment exclusively throughout the plant. This paper describes the philosophy and strategy which has been used to successfully implement this program for both existing plant facilities and plant expansions. Some of the problems that have been encountered include system selection, vendor support, soft- ware development, system security and system reliability. How these problems arose, were overcome and how they can be prevented in future projects is discussed. A key element of the success has been the organization of the technical, engineering and maintenance efforts and also training has been found to be extremely important. Finally, the effect of these experiences upon present thinking is discussed.

Jan 1, 1984

By Owen F. Jensen

CONSTRUCTION of a ground-water supply includes many operations, which do not end with completion of facilities. Evaluations must be made of the quality of water in various areas and the history of production. Following an analysis of geologic, hydrologic, and chemical data there must be an exploratory drilling program and a study of resulting information. When the well is completed a continuous survey of operating records and basic data is necessary, since designs for future wells are varied as more data becomes available for those already completed. As the following discussion must be limited to a single undertaking, the customary procedure will be outlined for development and construction of a ground-water supply in which more than three wells are involved. Parts of this procedure are applicable for all ground-water supplies.

Jan 11, 1954