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By C. W. Sherman, J. Chipman, H. I. Elvander

J. F. Elliott—This is an excellent piece of work and makes a chemical metallurgist more enthusiastic than ever about what can be done with multicomponent systems, if we have satisfactory data. I have a remark to make on the interpretation of fig. 5. First, I will comment on the problem of activities in solutions. The iron-sulphur system has in its phase diagram an intermediate solid phase FeS. The occurrence of an intermediate phase is normally associated with negative departures from Raoult's law over a portion of the activity curves in the liquid. (Perhaps it would be better to reserve the phrase "departure from ideality" to departures from Raoult's law line rather than to departures from Henry's law line). Fig. 5 indicates that the deviation of the sulphur activity curve from the Henry's law line is negative;

Jan 1, 1951

By F. D. Rosi

IT was recently shown1 that slip bands can be observed in bent germanium crystals after deformation, by means of etch pits along the slip traces. It is the purpose of this note to show how chemical etch pits can also be usedto examine the appear- ance of slip bands in silicon, as well as other deformation markings. A 30 ohm-cm, p-type single crystal bar, 2x1/4x1/8 in., was plastically bent at approximately 1200°C in a vacuum of 1x10-5 mm Hg. The axis of the crystal was coincident with a <III> direction, and the surface normal to the axis of bending was within 4" of a (110) plane. Prior to the deformation, the (110) surface was mechanically polished with

Jan 1, 1958

By D. B. Barker, D. C. Holloway, J. F. Cardenas-Garcia

Tround International Inc. is currently developing a hard rock drill that uses a salvo of three frangible projectiles to prefracture the rock ahead of a conventional tri-cone bit. This paper reports on a series of experiments conducted for Tround to study the fragmentation enhancement possible through the use of an optimally timed and spaced salvo of projectiles. In this study the complex three-dimensional problem was simplified to a two dimensional salvo impact problem in a transparent brittle plate of glass. The use of high speed photography and dynamic photoelasticity was then used to study the development of the impact damage zone and the various interactions of the stress waves.

Jan 1, 1982

The Howe Memorial Lecture, in memory of Henry Marion Howe, Past President of the Institute, was authorized in April, 1923, as an annual address to be delivered by invitation under the auspices of the Institute by an individual of recognized and out- standing attainment in the science and practice of iron and steel metallurgy or metallography, chosen by the Board of Directors upon recommendation of the Iron and Steel Division. The follow- ing were the Howe lectures and lecturers for the years indicated: 1924 What is Steel? By Albert Sauveur. 1925 Austenite and Austenitic Steels. By John A. Mathems. 1926 Twenty-five Years of Metallography. By William Campbell. 1927 Alloy Steels. By Bradley Stoughton. 1928 Significance of the Simple Steel Analysis. By Henry D. Hibbard. 1929 Studies of Hadfield&apos;s Manganese Steel with the High-power Microscopa By John Howe Hall. 1930 The Future of the American Iron and Steel Industry. By Zay Jeffries. 1931 On the Art of Metallography. By Francis F. Lucas.

Jan 1, 1937

By R. W. Callen, W. A. Hockings

This paper describes a computer program which calculates material balances for complex steady-state material flow circuits encountered in mineral processing. The program determines mass flows in the various process streams of a flowsheet from multicomponent analytical data obtained from samples of the streams. The program, Metallurgical Balance System (MBS), has been used extensively in treating Pilot plant test data, in production evaluation and control, and in plant design. The program performs well even on ill-conditioned data. Input to the program is easily accomplished by unskilled personnel and the output appears in well-formatted tables.

Jan 1, 1981

The Library of the above-named Societies is open from 9 A.M. to 10 P.M., except on holidays. It contains about 70,000 volumes and 90,000 pamphlets, 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, through its Library Service Bureau, can render valuable service through correspondence; letters requesting information will receive especial attention. The Library is prepared to furnish references and photographic copies of articles on mining and metallurgical subjects; to determine the existence of mining maps, and to furnish general information on 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 natter 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.

Jan 2, 1917

By S. E. Craig

UPON entering the Uranium Field it was a pleasant surprise to find almost absent two factors that have always been a problem to the lead-zinc miner: 1) milling cost per ton, and 2) transportation cost to the milling site. Another interesting condition was the fixed price for the product. Under such conditions it seems rather simple to calculate the economics of a mining venture when grade and tonnage of a uranium ore deposit is known. That is assuming, of course, there is a market for the ore. It has been quite generally assumed by operators that a guaranteed price carried with it a guaranteed market, a subject about which there has been a great deal of discussion in the past several months. The fixed price for uranium in crude ore, calculated to U3O8, varies only slightly in value per pound from rather low grade ore to rather high grade ore. It is by taking advantage of this slight variation in price per pound in certain ranges that miners and shippers may increase substantially the monthly returns from ore shipments.

Jan 7, 1958

The mining of coal, phosphate, oil, gas, and sodium on the public lands of the United States has, during a long period of years, been prevented by the failure of Congress to legislate, notwithstanding the fact that each successive Congress has vainly attempted to enact a law. Disagreements among members of Congress, many of which have related to non-essential matters, have prevented the passage of a bill, the failure at the last session having been due to a fillibuster in the Senate against the conference report led by Senator LaFollette of Wisconsin. Seven bills covering this subject have been introduced into the present Congress, four of which are identical in nearly all essential respects and follow either precisely or closely the conference agreement of the last Congress. These bills are too long to permit of review in this column. In general they provide for the leasing of lands or privileges to mine or to recover the various minerals above mentioned under terms and conditions as to the amount of land that may be leased by any one applicant, the diligence with which the work must be prosecuted, the return or royalty demanded, and the term of the lease and extensions thereof.

Jan 8, 1919

Activity with the legislation proposing to liberalize War Minerals Relief Act has now started before the Committee on Mines and Mining of the House. They are considering House Joint Resolution No. 170, which brings out the fact that war minerals claims in excess of $15,000,000 had been filed but that a considerable portion of the claims are being denied because of the Attorney General&apos;s. interpretation of the Act. The resolution states that it was the intention. of Congress in passing the War Minerals Relief Act "that all producers of the minerals mentioned should be repaid such sums as they are in equity and good faith entitled." The Attorney General&apos;s opinion is that the request or demand must have been made on the claimant direct. The resolution provides. that all claimants "who in response to any personal, written or published request or demand from any of the Government agencies-mentioned-in said Act in good faith expended money in producing or preparing to produce any of the ores or minerals named-therein *-*-* and have heretofore filed their claims within the time and-in the manner prescribed in said Act" are to be reimbursed for the n t-losses-incurred.

Jan 12, 1919

By Byron Johnston

IN 1926 I had occasion to make numerous measure-ments with a Pitot tube. The differential gage was mounted in a box, and since the work entailed setting upon girders, staging, and flues of various shapes and slopes, much time was generally expended in getting the box blocked into the level position. This inconvenience was so considerable that I devised the gage stand shown in the accompanying illustration. The gage is bolted to the board seat, the bolt per-mitting unlimited adjustment in the plane of the paper. The seat, carrying the gage, revolves on trunnions, per-mitting unlimited adjustment in a second plane, per-pendicular to the first. Consequently, the stand may be stood up, hung by one corner, leaned against some-thing or simply laid down, and the gage levelled from any position. On uneven surfaces, where the stand naturally rests on only three of its legs, it may be swung in the manner peculiar to the tripod, bringing the center of gravity within the triangle formed by the legs, thereby providing a firm set-up. Rubber stoppers under compression were found to give sufficient friction to hold the seat in the desired position.

Jan 3, 1928

By Olev Trass

The mill body is a stationary grinding cylinder inside which a number of helically grooved rollers rotate, each being suspended on a flexible axis. The feed material is repeatedly crushed between these rotors and the cylinder, with the crushing force created by radial acceleration. The mill has several internal design variables such as number, size and shape of rotors, and can be operated wet or dry. It is compact, has a high capacity, modest power consumption, and can grind many materials down to ultrafine powder. Illustrative data on product size distributions and particle shapes are given for grains, metals and minerals obtained at various operating conditions, along with initial results on grinding kinetics.

Jan 1, 1980

By John V. Beall

Back in the days when it was possible to tell one sports season from another, the football season began the last Saturday in September and ended on Thanksgiving Day for most teams. There were one or two post-season bowl games on New Year Day; but that was it. Actually, ten weeks of football, counting preseason practice, was about all a player could stomach without going stale. Not that the boys were any softer back then; quite the contrary, a good player usually played 60 minutes of ball. We must admit that we played lots of football in those days too---but not on Saturday. Particularly we remember the Monday after the Saturday when Columbia beat the Georgia Tech team which was led by the great back, Frank Sinkowitch, by a score of 7 to 3. That Saturday Mr. Little actually played 14 men: that is there were three backfield substitutions, each of which was for a few minutes only. Georgia seemed to have a progressive coach because he alternated two squads by quarters.

Jan 1, 1970

COLUMBIA LOCAL SECTION STANLY A. EASTON, Chairman, FREDERIC KEFFER, Vice-Chairman, L. K. ARMSTRONG, Sec.-Treas., P. O. Drawer 2154, Spokane, Wash. The fifth annual meeting of the Columbia Local Section was held in Wallace, Idaho, November 19-20, 1915, with headquarters at the Samuel Hotel. The afternoon session scheduled for November 19, was adjourned to give the members an opportunity to hear the testimony in the case between the Alameda and Success mining. companies on trial in the Superior Court of Shoshone County. The Success Company offered some excellent mine models and maps and furnished some interesting testimony. In the evening a technical session was held at which Stanly A. Easton presided in the absence of the Chairman and Vice-Chairman of the Section. The following papers were read: Progress in Ore Dressing By D. W. Buckby,.. Mine Accounting for Small Mines, By J. E. Chapman. Zinc Smelting and Smelter Rates, By W. E. Henry.

Jan 2, 1916

By Sir John Cadman

IN THE changed circumstances which now confront the world, an international open-door policy is the only way to keep pace with the world&apos;s demand for oil. You may rest assured that as far as the British Empire is concerned, American capital for the develop-ment of oil resources is welcome, and little obstruction will be found in the way to permit the use of foreign capital in the group of countries which constitute the British Empire. In the war days we worked in close cooperation and harmony, but in disbandment of the Petroleum War Service Committee, when the war ended, I feel that it left its task unfinished. In the wake of war there appeared a ghost of war-time conditions in the form of belief that Great Britain was straining to corner the petroleum resources of the world. I am certain that if the war-service committee had continued its work in the period of reconstruction the real story would be known and this sinister ghost would have long since vanished before the truth.

Jan 2, 1922

By William Hamilton Merritt

At the Atlanta Meeting in October, 1895, a short paper was presented by Mr. R. W. Leonard on the " Assay of Auriferous Ores and Gravels by Amalgamation and the Blow-pipe" (Trans., xxv., 645), embodying the results of some very conclusive tests as to the value of the process. His arguments regarding the desirability of the process appear to be indisputable, but the practicability of the field-outfit used by him is open to question. The Province of Ontario, in which Kingston is situated, is still largely unexplored; and at the Kingstoil School of Mining we give much attention to the instruction of prospectors and the testing of ores. To this end, not only is there a small mill (to which Mr. Leonard alludes) attached to the school, but prospectors&apos; classes

Jan 1, 1897

The 118th, meeting of the Institute, which has been arranged primarily for the benefit of the Institute of Metals Division and of those members who are particularly interested in iron and steel, will be held in the Milwaukee Auditorium, Milwaukee, Wis., on Oct. 8 to 11, 1918. This date has been selected because at that time, and at the same place, the American Foundrymen&apos;s Association and the American Malleable Castings Association will hold meetings. A notable exhibit of metallurgical and mechanical processes and products, at which over 165 firms will be represented, has been arranged in Machinery Hall, of the Auditorium Building. Wherever practicable, the machinery will be in operation. The program of the Institute&apos;s sessions was published in Bulletin 141. A special announcement of the meeting, together with a program of the sessions of the American Foundrymen&apos;s Association, has been mailed to every member who was thought to be directly interested in the meeting. A report of the meeting-and of the discussion of papers will be printed in the December Bulletin.

Jan 10, 1918

By C. A. Stetefeldt

The hacienda Sauceda is one of the largest and finest haciendas in the vicinity of the City of Zacatecas, Mexico, and is said to reduce ores by the Patio process more cheaply than any other establishment. It receives its supply of ore from the San Acacio mine. This mine has been for some time, like most of the Zacatecas mines, out of bonanza, and yields, at present, ore of rather low grade. The silver occurs principally as silver-glance, ruby-silver and native silver, associated with pyrites of iron and copper, and some galena and zinc-blende, in a gangue of pure quartz, which takes the form of amythyst whenever the ore is of high grade. All the ore, as it comes from the mine, is broken by hand into small pieces, and sorted before it is delivered to the hacienda. Here it is first crushed dry in Chili mills, and then ground wet in arrastras to an impalpable powder. The sulphurets not decomposed in the patio process are separated in the settlers from the tailings and concentrated by hand. By roasting them in a reverberatory furnace with carbonate copperores, "magistral" is obtained. All machinery is driven by mulepower.

Jan 1, 1885

By T. C. Craig

During the year 1936, there were 654 oil wells drilled in the Texas Panhandle, with a total daily initial production of 256,049 bbl. Although 74 more wells were drilled than in the previous year, the total initial production lacked 109,303 bbl. to equal that of 1935. The explanation is that during 1935 most of the drilling was in the granite-wash area, which is much more prolific than the dolomite, in which the major development was done during 1936. Twenty-one oil wells were drilled deeper, increasing their potential 3683 bbl. The total daily oil potentid of the field Dec. 31, 1936, as determined by the Texas Railroad Commission, was 834,888 bbl., with a daily allowable production of 71,335 bbl. No overall field decline in production is recognized by the Texas Railroad Commission. A well is tested upon completion to determine its potential production. If the well is then shot with nitroglycerin or is treated with

Jan 1, 1937

By E. A. Sondreal, P. H. Tufte

Flue gas desulfurization when burning western U.S. coals can be expected to be easier to achieve and less costly than when burning higher sulfur eastern and central coals. However, western coals cannot generally be burned in compliance with federal and state new source emission standards without some degree of control. Western coals and lignite represent about 20% of total U.S. recoverable reserves with 90% of that strip minable, and their production is predicted to increase from the 60 million tons mined in 1973 to 300 million tons in 1985. Most will be used for electric power generation, where low sulfur content is a paramount concern. Western coals are predominantly below 1% sulfur; low compared with typical values of 2 and 3% for eastern and central coals. Coal cleaning for removal of sulfur is not commercially practiced on Western coals, which typically contain half organic and half pyritic sulfur. A fraction of the pyrite sulfur could possibly be removed, but the

Jan 1, 1976

The following resolution was passed by the Military Engineering Committee of New York on April 12, 1917. Copies are being sent to each member of Congress and to each of the five members in every State forming the committee representing, the five National engineering societies which carried on the industrial census under the direction of Howard Coffin. The Committee is urging every man to wire his Congressman and his Senator, asking him to do everything in his power to obtain favorable action by Congress on this resolution: Whereas in any large army to be created for the war, engineer troops will be needed in large numbers, and Whereas they should be officered by skilled engineers only, and Whereas the composition and training of such troops differ so much from the composition and training of non-technical troops that they should be organized under one central authority rather than under many scattered authorities. Now, therefore, be it resolved: That the members of the Senate and House of Representatives be requested to insist that all new units of engineer troops be organized and maintained by the War Department and not by the individual States.

Jan 6, 1917